Commit | Line | Data |
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8e86e015 | 1 | // SPDX-License-Identifier: GPL-2.0 |
0793a61d | 2 | /* |
57c0c15b | 3 | * Performance events core code: |
0793a61d | 4 | * |
98144511 | 5 | * Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de> |
e7e7ee2e | 6 | * Copyright (C) 2008-2011 Red Hat, Inc., Ingo Molnar |
90eec103 | 7 | * Copyright (C) 2008-2011 Red Hat, Inc., Peter Zijlstra |
d36b6910 | 8 | * Copyright © 2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com> |
0793a61d TG |
9 | */ |
10 | ||
11 | #include <linux/fs.h> | |
b9cacc7b | 12 | #include <linux/mm.h> |
0793a61d TG |
13 | #include <linux/cpu.h> |
14 | #include <linux/smp.h> | |
2e80a82a | 15 | #include <linux/idr.h> |
04289bb9 | 16 | #include <linux/file.h> |
0793a61d | 17 | #include <linux/poll.h> |
5a0e3ad6 | 18 | #include <linux/slab.h> |
76e1d904 | 19 | #include <linux/hash.h> |
12351ef8 | 20 | #include <linux/tick.h> |
0793a61d | 21 | #include <linux/sysfs.h> |
22a4f650 | 22 | #include <linux/dcache.h> |
0793a61d | 23 | #include <linux/percpu.h> |
22a4f650 | 24 | #include <linux/ptrace.h> |
c277443c | 25 | #include <linux/reboot.h> |
b9cacc7b | 26 | #include <linux/vmstat.h> |
abe43400 | 27 | #include <linux/device.h> |
6e5fdeed | 28 | #include <linux/export.h> |
906010b2 | 29 | #include <linux/vmalloc.h> |
b9cacc7b PZ |
30 | #include <linux/hardirq.h> |
31 | #include <linux/rculist.h> | |
0793a61d TG |
32 | #include <linux/uaccess.h> |
33 | #include <linux/syscalls.h> | |
34 | #include <linux/anon_inodes.h> | |
aa9c4c0f | 35 | #include <linux/kernel_stat.h> |
39bed6cb | 36 | #include <linux/cgroup.h> |
cdd6c482 | 37 | #include <linux/perf_event.h> |
af658dca | 38 | #include <linux/trace_events.h> |
3c502e7a | 39 | #include <linux/hw_breakpoint.h> |
c5ebcedb | 40 | #include <linux/mm_types.h> |
c464c76e | 41 | #include <linux/module.h> |
f972eb63 | 42 | #include <linux/mman.h> |
b3f20785 | 43 | #include <linux/compat.h> |
2541517c AS |
44 | #include <linux/bpf.h> |
45 | #include <linux/filter.h> | |
375637bc AS |
46 | #include <linux/namei.h> |
47 | #include <linux/parser.h> | |
e6017571 | 48 | #include <linux/sched/clock.h> |
6e84f315 | 49 | #include <linux/sched/mm.h> |
e4222673 HB |
50 | #include <linux/proc_ns.h> |
51 | #include <linux/mount.h> | |
0793a61d | 52 | |
76369139 FW |
53 | #include "internal.h" |
54 | ||
4e193bd4 TB |
55 | #include <asm/irq_regs.h> |
56 | ||
272325c4 PZ |
57 | typedef int (*remote_function_f)(void *); |
58 | ||
fe4b04fa | 59 | struct remote_function_call { |
e7e7ee2e | 60 | struct task_struct *p; |
272325c4 | 61 | remote_function_f func; |
e7e7ee2e IM |
62 | void *info; |
63 | int ret; | |
fe4b04fa PZ |
64 | }; |
65 | ||
66 | static void remote_function(void *data) | |
67 | { | |
68 | struct remote_function_call *tfc = data; | |
69 | struct task_struct *p = tfc->p; | |
70 | ||
71 | if (p) { | |
0da4cf3e PZ |
72 | /* -EAGAIN */ |
73 | if (task_cpu(p) != smp_processor_id()) | |
74 | return; | |
75 | ||
76 | /* | |
77 | * Now that we're on right CPU with IRQs disabled, we can test | |
78 | * if we hit the right task without races. | |
79 | */ | |
80 | ||
81 | tfc->ret = -ESRCH; /* No such (running) process */ | |
82 | if (p != current) | |
fe4b04fa PZ |
83 | return; |
84 | } | |
85 | ||
86 | tfc->ret = tfc->func(tfc->info); | |
87 | } | |
88 | ||
89 | /** | |
90 | * task_function_call - call a function on the cpu on which a task runs | |
91 | * @p: the task to evaluate | |
92 | * @func: the function to be called | |
93 | * @info: the function call argument | |
94 | * | |
95 | * Calls the function @func when the task is currently running. This might | |
96 | * be on the current CPU, which just calls the function directly | |
97 | * | |
98 | * returns: @func return value, or | |
99 | * -ESRCH - when the process isn't running | |
100 | * -EAGAIN - when the process moved away | |
101 | */ | |
102 | static int | |
272325c4 | 103 | task_function_call(struct task_struct *p, remote_function_f func, void *info) |
fe4b04fa PZ |
104 | { |
105 | struct remote_function_call data = { | |
e7e7ee2e IM |
106 | .p = p, |
107 | .func = func, | |
108 | .info = info, | |
0da4cf3e | 109 | .ret = -EAGAIN, |
fe4b04fa | 110 | }; |
0da4cf3e | 111 | int ret; |
fe4b04fa | 112 | |
0da4cf3e PZ |
113 | do { |
114 | ret = smp_call_function_single(task_cpu(p), remote_function, &data, 1); | |
115 | if (!ret) | |
116 | ret = data.ret; | |
117 | } while (ret == -EAGAIN); | |
fe4b04fa | 118 | |
0da4cf3e | 119 | return ret; |
fe4b04fa PZ |
120 | } |
121 | ||
122 | /** | |
123 | * cpu_function_call - call a function on the cpu | |
124 | * @func: the function to be called | |
125 | * @info: the function call argument | |
126 | * | |
127 | * Calls the function @func on the remote cpu. | |
128 | * | |
129 | * returns: @func return value or -ENXIO when the cpu is offline | |
130 | */ | |
272325c4 | 131 | static int cpu_function_call(int cpu, remote_function_f func, void *info) |
fe4b04fa PZ |
132 | { |
133 | struct remote_function_call data = { | |
e7e7ee2e IM |
134 | .p = NULL, |
135 | .func = func, | |
136 | .info = info, | |
137 | .ret = -ENXIO, /* No such CPU */ | |
fe4b04fa PZ |
138 | }; |
139 | ||
140 | smp_call_function_single(cpu, remote_function, &data, 1); | |
141 | ||
142 | return data.ret; | |
143 | } | |
144 | ||
fae3fde6 PZ |
145 | static inline struct perf_cpu_context * |
146 | __get_cpu_context(struct perf_event_context *ctx) | |
147 | { | |
148 | return this_cpu_ptr(ctx->pmu->pmu_cpu_context); | |
149 | } | |
150 | ||
151 | static void perf_ctx_lock(struct perf_cpu_context *cpuctx, | |
152 | struct perf_event_context *ctx) | |
0017960f | 153 | { |
fae3fde6 PZ |
154 | raw_spin_lock(&cpuctx->ctx.lock); |
155 | if (ctx) | |
156 | raw_spin_lock(&ctx->lock); | |
157 | } | |
158 | ||
159 | static void perf_ctx_unlock(struct perf_cpu_context *cpuctx, | |
160 | struct perf_event_context *ctx) | |
161 | { | |
162 | if (ctx) | |
163 | raw_spin_unlock(&ctx->lock); | |
164 | raw_spin_unlock(&cpuctx->ctx.lock); | |
165 | } | |
166 | ||
63b6da39 PZ |
167 | #define TASK_TOMBSTONE ((void *)-1L) |
168 | ||
169 | static bool is_kernel_event(struct perf_event *event) | |
170 | { | |
f47c02c0 | 171 | return READ_ONCE(event->owner) == TASK_TOMBSTONE; |
63b6da39 PZ |
172 | } |
173 | ||
39a43640 PZ |
174 | /* |
175 | * On task ctx scheduling... | |
176 | * | |
177 | * When !ctx->nr_events a task context will not be scheduled. This means | |
178 | * we can disable the scheduler hooks (for performance) without leaving | |
179 | * pending task ctx state. | |
180 | * | |
181 | * This however results in two special cases: | |
182 | * | |
183 | * - removing the last event from a task ctx; this is relatively straight | |
184 | * forward and is done in __perf_remove_from_context. | |
185 | * | |
186 | * - adding the first event to a task ctx; this is tricky because we cannot | |
187 | * rely on ctx->is_active and therefore cannot use event_function_call(). | |
188 | * See perf_install_in_context(). | |
189 | * | |
39a43640 PZ |
190 | * If ctx->nr_events, then ctx->is_active and cpuctx->task_ctx are set. |
191 | */ | |
192 | ||
fae3fde6 PZ |
193 | typedef void (*event_f)(struct perf_event *, struct perf_cpu_context *, |
194 | struct perf_event_context *, void *); | |
195 | ||
196 | struct event_function_struct { | |
197 | struct perf_event *event; | |
198 | event_f func; | |
199 | void *data; | |
200 | }; | |
201 | ||
202 | static int event_function(void *info) | |
203 | { | |
204 | struct event_function_struct *efs = info; | |
205 | struct perf_event *event = efs->event; | |
0017960f | 206 | struct perf_event_context *ctx = event->ctx; |
fae3fde6 PZ |
207 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
208 | struct perf_event_context *task_ctx = cpuctx->task_ctx; | |
63b6da39 | 209 | int ret = 0; |
fae3fde6 | 210 | |
16444645 | 211 | lockdep_assert_irqs_disabled(); |
fae3fde6 | 212 | |
63b6da39 | 213 | perf_ctx_lock(cpuctx, task_ctx); |
fae3fde6 PZ |
214 | /* |
215 | * Since we do the IPI call without holding ctx->lock things can have | |
216 | * changed, double check we hit the task we set out to hit. | |
fae3fde6 PZ |
217 | */ |
218 | if (ctx->task) { | |
63b6da39 | 219 | if (ctx->task != current) { |
0da4cf3e | 220 | ret = -ESRCH; |
63b6da39 PZ |
221 | goto unlock; |
222 | } | |
fae3fde6 | 223 | |
fae3fde6 PZ |
224 | /* |
225 | * We only use event_function_call() on established contexts, | |
226 | * and event_function() is only ever called when active (or | |
227 | * rather, we'll have bailed in task_function_call() or the | |
228 | * above ctx->task != current test), therefore we must have | |
229 | * ctx->is_active here. | |
230 | */ | |
231 | WARN_ON_ONCE(!ctx->is_active); | |
232 | /* | |
233 | * And since we have ctx->is_active, cpuctx->task_ctx must | |
234 | * match. | |
235 | */ | |
63b6da39 PZ |
236 | WARN_ON_ONCE(task_ctx != ctx); |
237 | } else { | |
238 | WARN_ON_ONCE(&cpuctx->ctx != ctx); | |
fae3fde6 | 239 | } |
63b6da39 | 240 | |
fae3fde6 | 241 | efs->func(event, cpuctx, ctx, efs->data); |
63b6da39 | 242 | unlock: |
fae3fde6 PZ |
243 | perf_ctx_unlock(cpuctx, task_ctx); |
244 | ||
63b6da39 | 245 | return ret; |
fae3fde6 PZ |
246 | } |
247 | ||
fae3fde6 | 248 | static void event_function_call(struct perf_event *event, event_f func, void *data) |
0017960f PZ |
249 | { |
250 | struct perf_event_context *ctx = event->ctx; | |
63b6da39 | 251 | struct task_struct *task = READ_ONCE(ctx->task); /* verified in event_function */ |
fae3fde6 PZ |
252 | struct event_function_struct efs = { |
253 | .event = event, | |
254 | .func = func, | |
255 | .data = data, | |
256 | }; | |
0017960f | 257 | |
c97f4736 PZ |
258 | if (!event->parent) { |
259 | /* | |
260 | * If this is a !child event, we must hold ctx::mutex to | |
261 | * stabilize the the event->ctx relation. See | |
262 | * perf_event_ctx_lock(). | |
263 | */ | |
264 | lockdep_assert_held(&ctx->mutex); | |
265 | } | |
0017960f PZ |
266 | |
267 | if (!task) { | |
fae3fde6 | 268 | cpu_function_call(event->cpu, event_function, &efs); |
0017960f PZ |
269 | return; |
270 | } | |
271 | ||
63b6da39 PZ |
272 | if (task == TASK_TOMBSTONE) |
273 | return; | |
274 | ||
a096309b | 275 | again: |
fae3fde6 | 276 | if (!task_function_call(task, event_function, &efs)) |
0017960f PZ |
277 | return; |
278 | ||
279 | raw_spin_lock_irq(&ctx->lock); | |
63b6da39 PZ |
280 | /* |
281 | * Reload the task pointer, it might have been changed by | |
282 | * a concurrent perf_event_context_sched_out(). | |
283 | */ | |
284 | task = ctx->task; | |
a096309b PZ |
285 | if (task == TASK_TOMBSTONE) { |
286 | raw_spin_unlock_irq(&ctx->lock); | |
287 | return; | |
0017960f | 288 | } |
a096309b PZ |
289 | if (ctx->is_active) { |
290 | raw_spin_unlock_irq(&ctx->lock); | |
291 | goto again; | |
292 | } | |
293 | func(event, NULL, ctx, data); | |
0017960f PZ |
294 | raw_spin_unlock_irq(&ctx->lock); |
295 | } | |
296 | ||
cca20946 PZ |
297 | /* |
298 | * Similar to event_function_call() + event_function(), but hard assumes IRQs | |
299 | * are already disabled and we're on the right CPU. | |
300 | */ | |
301 | static void event_function_local(struct perf_event *event, event_f func, void *data) | |
302 | { | |
303 | struct perf_event_context *ctx = event->ctx; | |
304 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
305 | struct task_struct *task = READ_ONCE(ctx->task); | |
306 | struct perf_event_context *task_ctx = NULL; | |
307 | ||
16444645 | 308 | lockdep_assert_irqs_disabled(); |
cca20946 PZ |
309 | |
310 | if (task) { | |
311 | if (task == TASK_TOMBSTONE) | |
312 | return; | |
313 | ||
314 | task_ctx = ctx; | |
315 | } | |
316 | ||
317 | perf_ctx_lock(cpuctx, task_ctx); | |
318 | ||
319 | task = ctx->task; | |
320 | if (task == TASK_TOMBSTONE) | |
321 | goto unlock; | |
322 | ||
323 | if (task) { | |
324 | /* | |
325 | * We must be either inactive or active and the right task, | |
326 | * otherwise we're screwed, since we cannot IPI to somewhere | |
327 | * else. | |
328 | */ | |
329 | if (ctx->is_active) { | |
330 | if (WARN_ON_ONCE(task != current)) | |
331 | goto unlock; | |
332 | ||
333 | if (WARN_ON_ONCE(cpuctx->task_ctx != ctx)) | |
334 | goto unlock; | |
335 | } | |
336 | } else { | |
337 | WARN_ON_ONCE(&cpuctx->ctx != ctx); | |
338 | } | |
339 | ||
340 | func(event, cpuctx, ctx, data); | |
341 | unlock: | |
342 | perf_ctx_unlock(cpuctx, task_ctx); | |
343 | } | |
344 | ||
e5d1367f SE |
345 | #define PERF_FLAG_ALL (PERF_FLAG_FD_NO_GROUP |\ |
346 | PERF_FLAG_FD_OUTPUT |\ | |
a21b0b35 YD |
347 | PERF_FLAG_PID_CGROUP |\ |
348 | PERF_FLAG_FD_CLOEXEC) | |
e5d1367f | 349 | |
bce38cd5 SE |
350 | /* |
351 | * branch priv levels that need permission checks | |
352 | */ | |
353 | #define PERF_SAMPLE_BRANCH_PERM_PLM \ | |
354 | (PERF_SAMPLE_BRANCH_KERNEL |\ | |
355 | PERF_SAMPLE_BRANCH_HV) | |
356 | ||
0b3fcf17 SE |
357 | enum event_type_t { |
358 | EVENT_FLEXIBLE = 0x1, | |
359 | EVENT_PINNED = 0x2, | |
3cbaa590 | 360 | EVENT_TIME = 0x4, |
487f05e1 AS |
361 | /* see ctx_resched() for details */ |
362 | EVENT_CPU = 0x8, | |
0b3fcf17 SE |
363 | EVENT_ALL = EVENT_FLEXIBLE | EVENT_PINNED, |
364 | }; | |
365 | ||
e5d1367f SE |
366 | /* |
367 | * perf_sched_events : >0 events exist | |
368 | * perf_cgroup_events: >0 per-cpu cgroup events exist on this cpu | |
369 | */ | |
9107c89e PZ |
370 | |
371 | static void perf_sched_delayed(struct work_struct *work); | |
372 | DEFINE_STATIC_KEY_FALSE(perf_sched_events); | |
373 | static DECLARE_DELAYED_WORK(perf_sched_work, perf_sched_delayed); | |
374 | static DEFINE_MUTEX(perf_sched_mutex); | |
375 | static atomic_t perf_sched_count; | |
376 | ||
e5d1367f | 377 | static DEFINE_PER_CPU(atomic_t, perf_cgroup_events); |
ba532500 | 378 | static DEFINE_PER_CPU(int, perf_sched_cb_usages); |
f2fb6bef | 379 | static DEFINE_PER_CPU(struct pmu_event_list, pmu_sb_events); |
e5d1367f | 380 | |
cdd6c482 IM |
381 | static atomic_t nr_mmap_events __read_mostly; |
382 | static atomic_t nr_comm_events __read_mostly; | |
e4222673 | 383 | static atomic_t nr_namespaces_events __read_mostly; |
cdd6c482 | 384 | static atomic_t nr_task_events __read_mostly; |
948b26b6 | 385 | static atomic_t nr_freq_events __read_mostly; |
45ac1403 | 386 | static atomic_t nr_switch_events __read_mostly; |
76193a94 | 387 | static atomic_t nr_ksymbol_events __read_mostly; |
6ee52e2a | 388 | static atomic_t nr_bpf_events __read_mostly; |
9ee318a7 | 389 | |
108b02cf PZ |
390 | static LIST_HEAD(pmus); |
391 | static DEFINE_MUTEX(pmus_lock); | |
392 | static struct srcu_struct pmus_srcu; | |
a63fbed7 | 393 | static cpumask_var_t perf_online_mask; |
108b02cf | 394 | |
0764771d | 395 | /* |
cdd6c482 | 396 | * perf event paranoia level: |
0fbdea19 IM |
397 | * -1 - not paranoid at all |
398 | * 0 - disallow raw tracepoint access for unpriv | |
cdd6c482 | 399 | * 1 - disallow cpu events for unpriv |
0fbdea19 | 400 | * 2 - disallow kernel profiling for unpriv |
0764771d | 401 | */ |
0161028b | 402 | int sysctl_perf_event_paranoid __read_mostly = 2; |
0764771d | 403 | |
20443384 FW |
404 | /* Minimum for 512 kiB + 1 user control page */ |
405 | int sysctl_perf_event_mlock __read_mostly = 512 + (PAGE_SIZE / 1024); /* 'free' kiB per user */ | |
df58ab24 PZ |
406 | |
407 | /* | |
cdd6c482 | 408 | * max perf event sample rate |
df58ab24 | 409 | */ |
14c63f17 DH |
410 | #define DEFAULT_MAX_SAMPLE_RATE 100000 |
411 | #define DEFAULT_SAMPLE_PERIOD_NS (NSEC_PER_SEC / DEFAULT_MAX_SAMPLE_RATE) | |
412 | #define DEFAULT_CPU_TIME_MAX_PERCENT 25 | |
413 | ||
414 | int sysctl_perf_event_sample_rate __read_mostly = DEFAULT_MAX_SAMPLE_RATE; | |
415 | ||
416 | static int max_samples_per_tick __read_mostly = DIV_ROUND_UP(DEFAULT_MAX_SAMPLE_RATE, HZ); | |
417 | static int perf_sample_period_ns __read_mostly = DEFAULT_SAMPLE_PERIOD_NS; | |
418 | ||
d9494cb4 PZ |
419 | static int perf_sample_allowed_ns __read_mostly = |
420 | DEFAULT_SAMPLE_PERIOD_NS * DEFAULT_CPU_TIME_MAX_PERCENT / 100; | |
14c63f17 | 421 | |
18ab2cd3 | 422 | static void update_perf_cpu_limits(void) |
14c63f17 DH |
423 | { |
424 | u64 tmp = perf_sample_period_ns; | |
425 | ||
426 | tmp *= sysctl_perf_cpu_time_max_percent; | |
91a612ee PZ |
427 | tmp = div_u64(tmp, 100); |
428 | if (!tmp) | |
429 | tmp = 1; | |
430 | ||
431 | WRITE_ONCE(perf_sample_allowed_ns, tmp); | |
14c63f17 | 432 | } |
163ec435 | 433 | |
8d5bce0c | 434 | static bool perf_rotate_context(struct perf_cpu_context *cpuctx); |
9e630205 | 435 | |
163ec435 PZ |
436 | int perf_proc_update_handler(struct ctl_table *table, int write, |
437 | void __user *buffer, size_t *lenp, | |
438 | loff_t *ppos) | |
439 | { | |
1a51c5da SE |
440 | int ret; |
441 | int perf_cpu = sysctl_perf_cpu_time_max_percent; | |
ab7fdefb KL |
442 | /* |
443 | * If throttling is disabled don't allow the write: | |
444 | */ | |
1a51c5da | 445 | if (write && (perf_cpu == 100 || perf_cpu == 0)) |
ab7fdefb KL |
446 | return -EINVAL; |
447 | ||
1a51c5da SE |
448 | ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
449 | if (ret || !write) | |
450 | return ret; | |
451 | ||
163ec435 | 452 | max_samples_per_tick = DIV_ROUND_UP(sysctl_perf_event_sample_rate, HZ); |
14c63f17 DH |
453 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; |
454 | update_perf_cpu_limits(); | |
455 | ||
456 | return 0; | |
457 | } | |
458 | ||
459 | int sysctl_perf_cpu_time_max_percent __read_mostly = DEFAULT_CPU_TIME_MAX_PERCENT; | |
460 | ||
461 | int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write, | |
462 | void __user *buffer, size_t *lenp, | |
463 | loff_t *ppos) | |
464 | { | |
1572e45a | 465 | int ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
14c63f17 DH |
466 | |
467 | if (ret || !write) | |
468 | return ret; | |
469 | ||
b303e7c1 PZ |
470 | if (sysctl_perf_cpu_time_max_percent == 100 || |
471 | sysctl_perf_cpu_time_max_percent == 0) { | |
91a612ee PZ |
472 | printk(KERN_WARNING |
473 | "perf: Dynamic interrupt throttling disabled, can hang your system!\n"); | |
474 | WRITE_ONCE(perf_sample_allowed_ns, 0); | |
475 | } else { | |
476 | update_perf_cpu_limits(); | |
477 | } | |
163ec435 PZ |
478 | |
479 | return 0; | |
480 | } | |
1ccd1549 | 481 | |
14c63f17 DH |
482 | /* |
483 | * perf samples are done in some very critical code paths (NMIs). | |
484 | * If they take too much CPU time, the system can lock up and not | |
485 | * get any real work done. This will drop the sample rate when | |
486 | * we detect that events are taking too long. | |
487 | */ | |
488 | #define NR_ACCUMULATED_SAMPLES 128 | |
d9494cb4 | 489 | static DEFINE_PER_CPU(u64, running_sample_length); |
14c63f17 | 490 | |
91a612ee PZ |
491 | static u64 __report_avg; |
492 | static u64 __report_allowed; | |
493 | ||
6a02ad66 | 494 | static void perf_duration_warn(struct irq_work *w) |
14c63f17 | 495 | { |
0d87d7ec | 496 | printk_ratelimited(KERN_INFO |
91a612ee PZ |
497 | "perf: interrupt took too long (%lld > %lld), lowering " |
498 | "kernel.perf_event_max_sample_rate to %d\n", | |
499 | __report_avg, __report_allowed, | |
500 | sysctl_perf_event_sample_rate); | |
6a02ad66 PZ |
501 | } |
502 | ||
503 | static DEFINE_IRQ_WORK(perf_duration_work, perf_duration_warn); | |
504 | ||
505 | void perf_sample_event_took(u64 sample_len_ns) | |
506 | { | |
91a612ee PZ |
507 | u64 max_len = READ_ONCE(perf_sample_allowed_ns); |
508 | u64 running_len; | |
509 | u64 avg_len; | |
510 | u32 max; | |
14c63f17 | 511 | |
91a612ee | 512 | if (max_len == 0) |
14c63f17 DH |
513 | return; |
514 | ||
91a612ee PZ |
515 | /* Decay the counter by 1 average sample. */ |
516 | running_len = __this_cpu_read(running_sample_length); | |
517 | running_len -= running_len/NR_ACCUMULATED_SAMPLES; | |
518 | running_len += sample_len_ns; | |
519 | __this_cpu_write(running_sample_length, running_len); | |
14c63f17 DH |
520 | |
521 | /* | |
91a612ee PZ |
522 | * Note: this will be biased artifically low until we have |
523 | * seen NR_ACCUMULATED_SAMPLES. Doing it this way keeps us | |
14c63f17 DH |
524 | * from having to maintain a count. |
525 | */ | |
91a612ee PZ |
526 | avg_len = running_len/NR_ACCUMULATED_SAMPLES; |
527 | if (avg_len <= max_len) | |
14c63f17 DH |
528 | return; |
529 | ||
91a612ee PZ |
530 | __report_avg = avg_len; |
531 | __report_allowed = max_len; | |
14c63f17 | 532 | |
91a612ee PZ |
533 | /* |
534 | * Compute a throttle threshold 25% below the current duration. | |
535 | */ | |
536 | avg_len += avg_len / 4; | |
537 | max = (TICK_NSEC / 100) * sysctl_perf_cpu_time_max_percent; | |
538 | if (avg_len < max) | |
539 | max /= (u32)avg_len; | |
540 | else | |
541 | max = 1; | |
14c63f17 | 542 | |
91a612ee PZ |
543 | WRITE_ONCE(perf_sample_allowed_ns, avg_len); |
544 | WRITE_ONCE(max_samples_per_tick, max); | |
545 | ||
546 | sysctl_perf_event_sample_rate = max * HZ; | |
547 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; | |
6a02ad66 | 548 | |
cd578abb | 549 | if (!irq_work_queue(&perf_duration_work)) { |
91a612ee | 550 | early_printk("perf: interrupt took too long (%lld > %lld), lowering " |
cd578abb | 551 | "kernel.perf_event_max_sample_rate to %d\n", |
91a612ee | 552 | __report_avg, __report_allowed, |
cd578abb PZ |
553 | sysctl_perf_event_sample_rate); |
554 | } | |
14c63f17 DH |
555 | } |
556 | ||
cdd6c482 | 557 | static atomic64_t perf_event_id; |
a96bbc16 | 558 | |
0b3fcf17 SE |
559 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, |
560 | enum event_type_t event_type); | |
561 | ||
562 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
563 | enum event_type_t event_type, |
564 | struct task_struct *task); | |
565 | ||
566 | static void update_context_time(struct perf_event_context *ctx); | |
567 | static u64 perf_event_time(struct perf_event *event); | |
0b3fcf17 | 568 | |
cdd6c482 | 569 | void __weak perf_event_print_debug(void) { } |
0793a61d | 570 | |
84c79910 | 571 | extern __weak const char *perf_pmu_name(void) |
0793a61d | 572 | { |
84c79910 | 573 | return "pmu"; |
0793a61d TG |
574 | } |
575 | ||
0b3fcf17 SE |
576 | static inline u64 perf_clock(void) |
577 | { | |
578 | return local_clock(); | |
579 | } | |
580 | ||
34f43927 PZ |
581 | static inline u64 perf_event_clock(struct perf_event *event) |
582 | { | |
583 | return event->clock(); | |
584 | } | |
585 | ||
0d3d73aa PZ |
586 | /* |
587 | * State based event timekeeping... | |
588 | * | |
589 | * The basic idea is to use event->state to determine which (if any) time | |
590 | * fields to increment with the current delta. This means we only need to | |
591 | * update timestamps when we change state or when they are explicitly requested | |
592 | * (read). | |
593 | * | |
594 | * Event groups make things a little more complicated, but not terribly so. The | |
595 | * rules for a group are that if the group leader is OFF the entire group is | |
596 | * OFF, irrespecive of what the group member states are. This results in | |
597 | * __perf_effective_state(). | |
598 | * | |
599 | * A futher ramification is that when a group leader flips between OFF and | |
600 | * !OFF, we need to update all group member times. | |
601 | * | |
602 | * | |
603 | * NOTE: perf_event_time() is based on the (cgroup) context time, and thus we | |
604 | * need to make sure the relevant context time is updated before we try and | |
605 | * update our timestamps. | |
606 | */ | |
607 | ||
608 | static __always_inline enum perf_event_state | |
609 | __perf_effective_state(struct perf_event *event) | |
610 | { | |
611 | struct perf_event *leader = event->group_leader; | |
612 | ||
613 | if (leader->state <= PERF_EVENT_STATE_OFF) | |
614 | return leader->state; | |
615 | ||
616 | return event->state; | |
617 | } | |
618 | ||
619 | static __always_inline void | |
620 | __perf_update_times(struct perf_event *event, u64 now, u64 *enabled, u64 *running) | |
621 | { | |
622 | enum perf_event_state state = __perf_effective_state(event); | |
623 | u64 delta = now - event->tstamp; | |
624 | ||
625 | *enabled = event->total_time_enabled; | |
626 | if (state >= PERF_EVENT_STATE_INACTIVE) | |
627 | *enabled += delta; | |
628 | ||
629 | *running = event->total_time_running; | |
630 | if (state >= PERF_EVENT_STATE_ACTIVE) | |
631 | *running += delta; | |
632 | } | |
633 | ||
634 | static void perf_event_update_time(struct perf_event *event) | |
635 | { | |
636 | u64 now = perf_event_time(event); | |
637 | ||
638 | __perf_update_times(event, now, &event->total_time_enabled, | |
639 | &event->total_time_running); | |
640 | event->tstamp = now; | |
641 | } | |
642 | ||
643 | static void perf_event_update_sibling_time(struct perf_event *leader) | |
644 | { | |
645 | struct perf_event *sibling; | |
646 | ||
edb39592 | 647 | for_each_sibling_event(sibling, leader) |
0d3d73aa PZ |
648 | perf_event_update_time(sibling); |
649 | } | |
650 | ||
651 | static void | |
652 | perf_event_set_state(struct perf_event *event, enum perf_event_state state) | |
653 | { | |
654 | if (event->state == state) | |
655 | return; | |
656 | ||
657 | perf_event_update_time(event); | |
658 | /* | |
659 | * If a group leader gets enabled/disabled all its siblings | |
660 | * are affected too. | |
661 | */ | |
662 | if ((event->state < 0) ^ (state < 0)) | |
663 | perf_event_update_sibling_time(event); | |
664 | ||
665 | WRITE_ONCE(event->state, state); | |
666 | } | |
667 | ||
e5d1367f SE |
668 | #ifdef CONFIG_CGROUP_PERF |
669 | ||
e5d1367f SE |
670 | static inline bool |
671 | perf_cgroup_match(struct perf_event *event) | |
672 | { | |
673 | struct perf_event_context *ctx = event->ctx; | |
674 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
675 | ||
ef824fa1 TH |
676 | /* @event doesn't care about cgroup */ |
677 | if (!event->cgrp) | |
678 | return true; | |
679 | ||
680 | /* wants specific cgroup scope but @cpuctx isn't associated with any */ | |
681 | if (!cpuctx->cgrp) | |
682 | return false; | |
683 | ||
684 | /* | |
685 | * Cgroup scoping is recursive. An event enabled for a cgroup is | |
686 | * also enabled for all its descendant cgroups. If @cpuctx's | |
687 | * cgroup is a descendant of @event's (the test covers identity | |
688 | * case), it's a match. | |
689 | */ | |
690 | return cgroup_is_descendant(cpuctx->cgrp->css.cgroup, | |
691 | event->cgrp->css.cgroup); | |
e5d1367f SE |
692 | } |
693 | ||
e5d1367f SE |
694 | static inline void perf_detach_cgroup(struct perf_event *event) |
695 | { | |
4e2ba650 | 696 | css_put(&event->cgrp->css); |
e5d1367f SE |
697 | event->cgrp = NULL; |
698 | } | |
699 | ||
700 | static inline int is_cgroup_event(struct perf_event *event) | |
701 | { | |
702 | return event->cgrp != NULL; | |
703 | } | |
704 | ||
705 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
706 | { | |
707 | struct perf_cgroup_info *t; | |
708 | ||
709 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
710 | return t->time; | |
711 | } | |
712 | ||
713 | static inline void __update_cgrp_time(struct perf_cgroup *cgrp) | |
714 | { | |
715 | struct perf_cgroup_info *info; | |
716 | u64 now; | |
717 | ||
718 | now = perf_clock(); | |
719 | ||
720 | info = this_cpu_ptr(cgrp->info); | |
721 | ||
722 | info->time += now - info->timestamp; | |
723 | info->timestamp = now; | |
724 | } | |
725 | ||
726 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
727 | { | |
c917e0f2 SL |
728 | struct perf_cgroup *cgrp = cpuctx->cgrp; |
729 | struct cgroup_subsys_state *css; | |
730 | ||
731 | if (cgrp) { | |
732 | for (css = &cgrp->css; css; css = css->parent) { | |
733 | cgrp = container_of(css, struct perf_cgroup, css); | |
734 | __update_cgrp_time(cgrp); | |
735 | } | |
736 | } | |
e5d1367f SE |
737 | } |
738 | ||
739 | static inline void update_cgrp_time_from_event(struct perf_event *event) | |
740 | { | |
3f7cce3c SE |
741 | struct perf_cgroup *cgrp; |
742 | ||
e5d1367f | 743 | /* |
3f7cce3c SE |
744 | * ensure we access cgroup data only when needed and |
745 | * when we know the cgroup is pinned (css_get) | |
e5d1367f | 746 | */ |
3f7cce3c | 747 | if (!is_cgroup_event(event)) |
e5d1367f SE |
748 | return; |
749 | ||
614e4c4e | 750 | cgrp = perf_cgroup_from_task(current, event->ctx); |
3f7cce3c SE |
751 | /* |
752 | * Do not update time when cgroup is not active | |
753 | */ | |
28fa741c | 754 | if (cgroup_is_descendant(cgrp->css.cgroup, event->cgrp->css.cgroup)) |
3f7cce3c | 755 | __update_cgrp_time(event->cgrp); |
e5d1367f SE |
756 | } |
757 | ||
758 | static inline void | |
3f7cce3c SE |
759 | perf_cgroup_set_timestamp(struct task_struct *task, |
760 | struct perf_event_context *ctx) | |
e5d1367f SE |
761 | { |
762 | struct perf_cgroup *cgrp; | |
763 | struct perf_cgroup_info *info; | |
c917e0f2 | 764 | struct cgroup_subsys_state *css; |
e5d1367f | 765 | |
3f7cce3c SE |
766 | /* |
767 | * ctx->lock held by caller | |
768 | * ensure we do not access cgroup data | |
769 | * unless we have the cgroup pinned (css_get) | |
770 | */ | |
771 | if (!task || !ctx->nr_cgroups) | |
e5d1367f SE |
772 | return; |
773 | ||
614e4c4e | 774 | cgrp = perf_cgroup_from_task(task, ctx); |
c917e0f2 SL |
775 | |
776 | for (css = &cgrp->css; css; css = css->parent) { | |
777 | cgrp = container_of(css, struct perf_cgroup, css); | |
778 | info = this_cpu_ptr(cgrp->info); | |
779 | info->timestamp = ctx->timestamp; | |
780 | } | |
e5d1367f SE |
781 | } |
782 | ||
058fe1c0 DCC |
783 | static DEFINE_PER_CPU(struct list_head, cgrp_cpuctx_list); |
784 | ||
e5d1367f SE |
785 | #define PERF_CGROUP_SWOUT 0x1 /* cgroup switch out every event */ |
786 | #define PERF_CGROUP_SWIN 0x2 /* cgroup switch in events based on task */ | |
787 | ||
788 | /* | |
789 | * reschedule events based on the cgroup constraint of task. | |
790 | * | |
791 | * mode SWOUT : schedule out everything | |
792 | * mode SWIN : schedule in based on cgroup for next | |
793 | */ | |
18ab2cd3 | 794 | static void perf_cgroup_switch(struct task_struct *task, int mode) |
e5d1367f SE |
795 | { |
796 | struct perf_cpu_context *cpuctx; | |
058fe1c0 | 797 | struct list_head *list; |
e5d1367f SE |
798 | unsigned long flags; |
799 | ||
800 | /* | |
058fe1c0 DCC |
801 | * Disable interrupts and preemption to avoid this CPU's |
802 | * cgrp_cpuctx_entry to change under us. | |
e5d1367f SE |
803 | */ |
804 | local_irq_save(flags); | |
805 | ||
058fe1c0 DCC |
806 | list = this_cpu_ptr(&cgrp_cpuctx_list); |
807 | list_for_each_entry(cpuctx, list, cgrp_cpuctx_entry) { | |
808 | WARN_ON_ONCE(cpuctx->ctx.nr_cgroups == 0); | |
e5d1367f | 809 | |
058fe1c0 DCC |
810 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
811 | perf_pmu_disable(cpuctx->ctx.pmu); | |
e5d1367f | 812 | |
058fe1c0 DCC |
813 | if (mode & PERF_CGROUP_SWOUT) { |
814 | cpu_ctx_sched_out(cpuctx, EVENT_ALL); | |
815 | /* | |
816 | * must not be done before ctxswout due | |
817 | * to event_filter_match() in event_sched_out() | |
818 | */ | |
819 | cpuctx->cgrp = NULL; | |
820 | } | |
e5d1367f | 821 | |
058fe1c0 DCC |
822 | if (mode & PERF_CGROUP_SWIN) { |
823 | WARN_ON_ONCE(cpuctx->cgrp); | |
824 | /* | |
825 | * set cgrp before ctxsw in to allow | |
826 | * event_filter_match() to not have to pass | |
827 | * task around | |
828 | * we pass the cpuctx->ctx to perf_cgroup_from_task() | |
829 | * because cgorup events are only per-cpu | |
830 | */ | |
831 | cpuctx->cgrp = perf_cgroup_from_task(task, | |
832 | &cpuctx->ctx); | |
833 | cpu_ctx_sched_in(cpuctx, EVENT_ALL, task); | |
e5d1367f | 834 | } |
058fe1c0 DCC |
835 | perf_pmu_enable(cpuctx->ctx.pmu); |
836 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
e5d1367f SE |
837 | } |
838 | ||
e5d1367f SE |
839 | local_irq_restore(flags); |
840 | } | |
841 | ||
a8d757ef SE |
842 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
843 | struct task_struct *next) | |
e5d1367f | 844 | { |
a8d757ef SE |
845 | struct perf_cgroup *cgrp1; |
846 | struct perf_cgroup *cgrp2 = NULL; | |
847 | ||
ddaaf4e2 | 848 | rcu_read_lock(); |
a8d757ef SE |
849 | /* |
850 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
851 | * we do not need to pass the ctx here because we know |
852 | * we are holding the rcu lock | |
a8d757ef | 853 | */ |
614e4c4e | 854 | cgrp1 = perf_cgroup_from_task(task, NULL); |
70a01657 | 855 | cgrp2 = perf_cgroup_from_task(next, NULL); |
a8d757ef SE |
856 | |
857 | /* | |
858 | * only schedule out current cgroup events if we know | |
859 | * that we are switching to a different cgroup. Otherwise, | |
860 | * do no touch the cgroup events. | |
861 | */ | |
862 | if (cgrp1 != cgrp2) | |
863 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT); | |
ddaaf4e2 SE |
864 | |
865 | rcu_read_unlock(); | |
e5d1367f SE |
866 | } |
867 | ||
a8d757ef SE |
868 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
869 | struct task_struct *task) | |
e5d1367f | 870 | { |
a8d757ef SE |
871 | struct perf_cgroup *cgrp1; |
872 | struct perf_cgroup *cgrp2 = NULL; | |
873 | ||
ddaaf4e2 | 874 | rcu_read_lock(); |
a8d757ef SE |
875 | /* |
876 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
877 | * we do not need to pass the ctx here because we know |
878 | * we are holding the rcu lock | |
a8d757ef | 879 | */ |
614e4c4e | 880 | cgrp1 = perf_cgroup_from_task(task, NULL); |
614e4c4e | 881 | cgrp2 = perf_cgroup_from_task(prev, NULL); |
a8d757ef SE |
882 | |
883 | /* | |
884 | * only need to schedule in cgroup events if we are changing | |
885 | * cgroup during ctxsw. Cgroup events were not scheduled | |
886 | * out of ctxsw out if that was not the case. | |
887 | */ | |
888 | if (cgrp1 != cgrp2) | |
889 | perf_cgroup_switch(task, PERF_CGROUP_SWIN); | |
ddaaf4e2 SE |
890 | |
891 | rcu_read_unlock(); | |
e5d1367f SE |
892 | } |
893 | ||
894 | static inline int perf_cgroup_connect(int fd, struct perf_event *event, | |
895 | struct perf_event_attr *attr, | |
896 | struct perf_event *group_leader) | |
897 | { | |
898 | struct perf_cgroup *cgrp; | |
899 | struct cgroup_subsys_state *css; | |
2903ff01 AV |
900 | struct fd f = fdget(fd); |
901 | int ret = 0; | |
e5d1367f | 902 | |
2903ff01 | 903 | if (!f.file) |
e5d1367f SE |
904 | return -EBADF; |
905 | ||
b583043e | 906 | css = css_tryget_online_from_dir(f.file->f_path.dentry, |
ec903c0c | 907 | &perf_event_cgrp_subsys); |
3db272c0 LZ |
908 | if (IS_ERR(css)) { |
909 | ret = PTR_ERR(css); | |
910 | goto out; | |
911 | } | |
e5d1367f SE |
912 | |
913 | cgrp = container_of(css, struct perf_cgroup, css); | |
914 | event->cgrp = cgrp; | |
915 | ||
916 | /* | |
917 | * all events in a group must monitor | |
918 | * the same cgroup because a task belongs | |
919 | * to only one perf cgroup at a time | |
920 | */ | |
921 | if (group_leader && group_leader->cgrp != cgrp) { | |
922 | perf_detach_cgroup(event); | |
923 | ret = -EINVAL; | |
e5d1367f | 924 | } |
3db272c0 | 925 | out: |
2903ff01 | 926 | fdput(f); |
e5d1367f SE |
927 | return ret; |
928 | } | |
929 | ||
930 | static inline void | |
931 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
932 | { | |
933 | struct perf_cgroup_info *t; | |
934 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
935 | event->shadow_ctx_time = now - t->timestamp; | |
936 | } | |
937 | ||
db4a8356 DCC |
938 | /* |
939 | * Update cpuctx->cgrp so that it is set when first cgroup event is added and | |
940 | * cleared when last cgroup event is removed. | |
941 | */ | |
942 | static inline void | |
943 | list_update_cgroup_event(struct perf_event *event, | |
944 | struct perf_event_context *ctx, bool add) | |
945 | { | |
946 | struct perf_cpu_context *cpuctx; | |
058fe1c0 | 947 | struct list_head *cpuctx_entry; |
db4a8356 DCC |
948 | |
949 | if (!is_cgroup_event(event)) | |
950 | return; | |
951 | ||
db4a8356 DCC |
952 | /* |
953 | * Because cgroup events are always per-cpu events, | |
07c59729 | 954 | * @ctx == &cpuctx->ctx. |
db4a8356 | 955 | */ |
07c59729 | 956 | cpuctx = container_of(ctx, struct perf_cpu_context, ctx); |
33801b94 | 957 | |
958 | /* | |
959 | * Since setting cpuctx->cgrp is conditional on the current @cgrp | |
960 | * matching the event's cgroup, we must do this for every new event, | |
961 | * because if the first would mismatch, the second would not try again | |
962 | * and we would leave cpuctx->cgrp unset. | |
963 | */ | |
964 | if (add && !cpuctx->cgrp) { | |
be96b316 TH |
965 | struct perf_cgroup *cgrp = perf_cgroup_from_task(current, ctx); |
966 | ||
be96b316 TH |
967 | if (cgroup_is_descendant(cgrp->css.cgroup, event->cgrp->css.cgroup)) |
968 | cpuctx->cgrp = cgrp; | |
058fe1c0 | 969 | } |
33801b94 | 970 | |
971 | if (add && ctx->nr_cgroups++) | |
972 | return; | |
973 | else if (!add && --ctx->nr_cgroups) | |
974 | return; | |
975 | ||
976 | /* no cgroup running */ | |
977 | if (!add) | |
978 | cpuctx->cgrp = NULL; | |
979 | ||
980 | cpuctx_entry = &cpuctx->cgrp_cpuctx_entry; | |
981 | if (add) | |
07c59729 SL |
982 | list_add(cpuctx_entry, |
983 | per_cpu_ptr(&cgrp_cpuctx_list, event->cpu)); | |
33801b94 | 984 | else |
985 | list_del(cpuctx_entry); | |
db4a8356 DCC |
986 | } |
987 | ||
e5d1367f SE |
988 | #else /* !CONFIG_CGROUP_PERF */ |
989 | ||
990 | static inline bool | |
991 | perf_cgroup_match(struct perf_event *event) | |
992 | { | |
993 | return true; | |
994 | } | |
995 | ||
996 | static inline void perf_detach_cgroup(struct perf_event *event) | |
997 | {} | |
998 | ||
999 | static inline int is_cgroup_event(struct perf_event *event) | |
1000 | { | |
1001 | return 0; | |
1002 | } | |
1003 | ||
e5d1367f SE |
1004 | static inline void update_cgrp_time_from_event(struct perf_event *event) |
1005 | { | |
1006 | } | |
1007 | ||
1008 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
1009 | { | |
1010 | } | |
1011 | ||
a8d757ef SE |
1012 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
1013 | struct task_struct *next) | |
e5d1367f SE |
1014 | { |
1015 | } | |
1016 | ||
a8d757ef SE |
1017 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
1018 | struct task_struct *task) | |
e5d1367f SE |
1019 | { |
1020 | } | |
1021 | ||
1022 | static inline int perf_cgroup_connect(pid_t pid, struct perf_event *event, | |
1023 | struct perf_event_attr *attr, | |
1024 | struct perf_event *group_leader) | |
1025 | { | |
1026 | return -EINVAL; | |
1027 | } | |
1028 | ||
1029 | static inline void | |
3f7cce3c SE |
1030 | perf_cgroup_set_timestamp(struct task_struct *task, |
1031 | struct perf_event_context *ctx) | |
e5d1367f SE |
1032 | { |
1033 | } | |
1034 | ||
d00dbd29 | 1035 | static inline void |
e5d1367f SE |
1036 | perf_cgroup_switch(struct task_struct *task, struct task_struct *next) |
1037 | { | |
1038 | } | |
1039 | ||
1040 | static inline void | |
1041 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
1042 | { | |
1043 | } | |
1044 | ||
1045 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
1046 | { | |
1047 | return 0; | |
1048 | } | |
1049 | ||
db4a8356 DCC |
1050 | static inline void |
1051 | list_update_cgroup_event(struct perf_event *event, | |
1052 | struct perf_event_context *ctx, bool add) | |
1053 | { | |
1054 | } | |
1055 | ||
e5d1367f SE |
1056 | #endif |
1057 | ||
9e630205 SE |
1058 | /* |
1059 | * set default to be dependent on timer tick just | |
1060 | * like original code | |
1061 | */ | |
1062 | #define PERF_CPU_HRTIMER (1000 / HZ) | |
1063 | /* | |
8a1115ff | 1064 | * function must be called with interrupts disabled |
9e630205 | 1065 | */ |
272325c4 | 1066 | static enum hrtimer_restart perf_mux_hrtimer_handler(struct hrtimer *hr) |
9e630205 SE |
1067 | { |
1068 | struct perf_cpu_context *cpuctx; | |
8d5bce0c | 1069 | bool rotations; |
9e630205 | 1070 | |
16444645 | 1071 | lockdep_assert_irqs_disabled(); |
9e630205 SE |
1072 | |
1073 | cpuctx = container_of(hr, struct perf_cpu_context, hrtimer); | |
9e630205 SE |
1074 | rotations = perf_rotate_context(cpuctx); |
1075 | ||
4cfafd30 PZ |
1076 | raw_spin_lock(&cpuctx->hrtimer_lock); |
1077 | if (rotations) | |
9e630205 | 1078 | hrtimer_forward_now(hr, cpuctx->hrtimer_interval); |
4cfafd30 PZ |
1079 | else |
1080 | cpuctx->hrtimer_active = 0; | |
1081 | raw_spin_unlock(&cpuctx->hrtimer_lock); | |
9e630205 | 1082 | |
4cfafd30 | 1083 | return rotations ? HRTIMER_RESTART : HRTIMER_NORESTART; |
9e630205 SE |
1084 | } |
1085 | ||
272325c4 | 1086 | static void __perf_mux_hrtimer_init(struct perf_cpu_context *cpuctx, int cpu) |
9e630205 | 1087 | { |
272325c4 | 1088 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1089 | struct pmu *pmu = cpuctx->ctx.pmu; |
272325c4 | 1090 | u64 interval; |
9e630205 SE |
1091 | |
1092 | /* no multiplexing needed for SW PMU */ | |
1093 | if (pmu->task_ctx_nr == perf_sw_context) | |
1094 | return; | |
1095 | ||
62b85639 SE |
1096 | /* |
1097 | * check default is sane, if not set then force to | |
1098 | * default interval (1/tick) | |
1099 | */ | |
272325c4 PZ |
1100 | interval = pmu->hrtimer_interval_ms; |
1101 | if (interval < 1) | |
1102 | interval = pmu->hrtimer_interval_ms = PERF_CPU_HRTIMER; | |
62b85639 | 1103 | |
272325c4 | 1104 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * interval); |
9e630205 | 1105 | |
4cfafd30 | 1106 | raw_spin_lock_init(&cpuctx->hrtimer_lock); |
30f9028b | 1107 | hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_PINNED_HARD); |
272325c4 | 1108 | timer->function = perf_mux_hrtimer_handler; |
9e630205 SE |
1109 | } |
1110 | ||
272325c4 | 1111 | static int perf_mux_hrtimer_restart(struct perf_cpu_context *cpuctx) |
9e630205 | 1112 | { |
272325c4 | 1113 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1114 | struct pmu *pmu = cpuctx->ctx.pmu; |
4cfafd30 | 1115 | unsigned long flags; |
9e630205 SE |
1116 | |
1117 | /* not for SW PMU */ | |
1118 | if (pmu->task_ctx_nr == perf_sw_context) | |
272325c4 | 1119 | return 0; |
9e630205 | 1120 | |
4cfafd30 PZ |
1121 | raw_spin_lock_irqsave(&cpuctx->hrtimer_lock, flags); |
1122 | if (!cpuctx->hrtimer_active) { | |
1123 | cpuctx->hrtimer_active = 1; | |
1124 | hrtimer_forward_now(timer, cpuctx->hrtimer_interval); | |
30f9028b | 1125 | hrtimer_start_expires(timer, HRTIMER_MODE_ABS_PINNED_HARD); |
4cfafd30 PZ |
1126 | } |
1127 | raw_spin_unlock_irqrestore(&cpuctx->hrtimer_lock, flags); | |
9e630205 | 1128 | |
272325c4 | 1129 | return 0; |
9e630205 SE |
1130 | } |
1131 | ||
33696fc0 | 1132 | void perf_pmu_disable(struct pmu *pmu) |
9e35ad38 | 1133 | { |
33696fc0 PZ |
1134 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1135 | if (!(*count)++) | |
1136 | pmu->pmu_disable(pmu); | |
9e35ad38 | 1137 | } |
9e35ad38 | 1138 | |
33696fc0 | 1139 | void perf_pmu_enable(struct pmu *pmu) |
9e35ad38 | 1140 | { |
33696fc0 PZ |
1141 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1142 | if (!--(*count)) | |
1143 | pmu->pmu_enable(pmu); | |
9e35ad38 | 1144 | } |
9e35ad38 | 1145 | |
2fde4f94 | 1146 | static DEFINE_PER_CPU(struct list_head, active_ctx_list); |
e9d2b064 PZ |
1147 | |
1148 | /* | |
2fde4f94 MR |
1149 | * perf_event_ctx_activate(), perf_event_ctx_deactivate(), and |
1150 | * perf_event_task_tick() are fully serialized because they're strictly cpu | |
1151 | * affine and perf_event_ctx{activate,deactivate} are called with IRQs | |
1152 | * disabled, while perf_event_task_tick is called from IRQ context. | |
e9d2b064 | 1153 | */ |
2fde4f94 | 1154 | static void perf_event_ctx_activate(struct perf_event_context *ctx) |
9e35ad38 | 1155 | { |
2fde4f94 | 1156 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
b5ab4cd5 | 1157 | |
16444645 | 1158 | lockdep_assert_irqs_disabled(); |
b5ab4cd5 | 1159 | |
2fde4f94 MR |
1160 | WARN_ON(!list_empty(&ctx->active_ctx_list)); |
1161 | ||
1162 | list_add(&ctx->active_ctx_list, head); | |
1163 | } | |
1164 | ||
1165 | static void perf_event_ctx_deactivate(struct perf_event_context *ctx) | |
1166 | { | |
16444645 | 1167 | lockdep_assert_irqs_disabled(); |
2fde4f94 MR |
1168 | |
1169 | WARN_ON(list_empty(&ctx->active_ctx_list)); | |
1170 | ||
1171 | list_del_init(&ctx->active_ctx_list); | |
9e35ad38 | 1172 | } |
9e35ad38 | 1173 | |
cdd6c482 | 1174 | static void get_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1175 | { |
8c94abbb | 1176 | refcount_inc(&ctx->refcount); |
a63eaf34 PM |
1177 | } |
1178 | ||
4af57ef2 YZ |
1179 | static void free_ctx(struct rcu_head *head) |
1180 | { | |
1181 | struct perf_event_context *ctx; | |
1182 | ||
1183 | ctx = container_of(head, struct perf_event_context, rcu_head); | |
1184 | kfree(ctx->task_ctx_data); | |
1185 | kfree(ctx); | |
1186 | } | |
1187 | ||
cdd6c482 | 1188 | static void put_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1189 | { |
8c94abbb | 1190 | if (refcount_dec_and_test(&ctx->refcount)) { |
564c2b21 PM |
1191 | if (ctx->parent_ctx) |
1192 | put_ctx(ctx->parent_ctx); | |
63b6da39 | 1193 | if (ctx->task && ctx->task != TASK_TOMBSTONE) |
c93f7669 | 1194 | put_task_struct(ctx->task); |
4af57ef2 | 1195 | call_rcu(&ctx->rcu_head, free_ctx); |
564c2b21 | 1196 | } |
a63eaf34 PM |
1197 | } |
1198 | ||
f63a8daa PZ |
1199 | /* |
1200 | * Because of perf_event::ctx migration in sys_perf_event_open::move_group and | |
1201 | * perf_pmu_migrate_context() we need some magic. | |
1202 | * | |
1203 | * Those places that change perf_event::ctx will hold both | |
1204 | * perf_event_ctx::mutex of the 'old' and 'new' ctx value. | |
1205 | * | |
8b10c5e2 PZ |
1206 | * Lock ordering is by mutex address. There are two other sites where |
1207 | * perf_event_context::mutex nests and those are: | |
1208 | * | |
1209 | * - perf_event_exit_task_context() [ child , 0 ] | |
8ba289b8 PZ |
1210 | * perf_event_exit_event() |
1211 | * put_event() [ parent, 1 ] | |
8b10c5e2 PZ |
1212 | * |
1213 | * - perf_event_init_context() [ parent, 0 ] | |
1214 | * inherit_task_group() | |
1215 | * inherit_group() | |
1216 | * inherit_event() | |
1217 | * perf_event_alloc() | |
1218 | * perf_init_event() | |
1219 | * perf_try_init_event() [ child , 1 ] | |
1220 | * | |
1221 | * While it appears there is an obvious deadlock here -- the parent and child | |
1222 | * nesting levels are inverted between the two. This is in fact safe because | |
1223 | * life-time rules separate them. That is an exiting task cannot fork, and a | |
1224 | * spawning task cannot (yet) exit. | |
1225 | * | |
1226 | * But remember that that these are parent<->child context relations, and | |
1227 | * migration does not affect children, therefore these two orderings should not | |
1228 | * interact. | |
f63a8daa PZ |
1229 | * |
1230 | * The change in perf_event::ctx does not affect children (as claimed above) | |
1231 | * because the sys_perf_event_open() case will install a new event and break | |
1232 | * the ctx parent<->child relation, and perf_pmu_migrate_context() is only | |
1233 | * concerned with cpuctx and that doesn't have children. | |
1234 | * | |
1235 | * The places that change perf_event::ctx will issue: | |
1236 | * | |
1237 | * perf_remove_from_context(); | |
1238 | * synchronize_rcu(); | |
1239 | * perf_install_in_context(); | |
1240 | * | |
1241 | * to affect the change. The remove_from_context() + synchronize_rcu() should | |
1242 | * quiesce the event, after which we can install it in the new location. This | |
1243 | * means that only external vectors (perf_fops, prctl) can perturb the event | |
1244 | * while in transit. Therefore all such accessors should also acquire | |
1245 | * perf_event_context::mutex to serialize against this. | |
1246 | * | |
1247 | * However; because event->ctx can change while we're waiting to acquire | |
1248 | * ctx->mutex we must be careful and use the below perf_event_ctx_lock() | |
1249 | * function. | |
1250 | * | |
1251 | * Lock order: | |
79c9ce57 | 1252 | * cred_guard_mutex |
f63a8daa PZ |
1253 | * task_struct::perf_event_mutex |
1254 | * perf_event_context::mutex | |
f63a8daa | 1255 | * perf_event::child_mutex; |
07c4a776 | 1256 | * perf_event_context::lock |
f63a8daa PZ |
1257 | * perf_event::mmap_mutex |
1258 | * mmap_sem | |
18736eef | 1259 | * perf_addr_filters_head::lock |
82d94856 PZ |
1260 | * |
1261 | * cpu_hotplug_lock | |
1262 | * pmus_lock | |
1263 | * cpuctx->mutex / perf_event_context::mutex | |
f63a8daa | 1264 | */ |
a83fe28e PZ |
1265 | static struct perf_event_context * |
1266 | perf_event_ctx_lock_nested(struct perf_event *event, int nesting) | |
f63a8daa PZ |
1267 | { |
1268 | struct perf_event_context *ctx; | |
1269 | ||
1270 | again: | |
1271 | rcu_read_lock(); | |
6aa7de05 | 1272 | ctx = READ_ONCE(event->ctx); |
8c94abbb | 1273 | if (!refcount_inc_not_zero(&ctx->refcount)) { |
f63a8daa PZ |
1274 | rcu_read_unlock(); |
1275 | goto again; | |
1276 | } | |
1277 | rcu_read_unlock(); | |
1278 | ||
a83fe28e | 1279 | mutex_lock_nested(&ctx->mutex, nesting); |
f63a8daa PZ |
1280 | if (event->ctx != ctx) { |
1281 | mutex_unlock(&ctx->mutex); | |
1282 | put_ctx(ctx); | |
1283 | goto again; | |
1284 | } | |
1285 | ||
1286 | return ctx; | |
1287 | } | |
1288 | ||
a83fe28e PZ |
1289 | static inline struct perf_event_context * |
1290 | perf_event_ctx_lock(struct perf_event *event) | |
1291 | { | |
1292 | return perf_event_ctx_lock_nested(event, 0); | |
1293 | } | |
1294 | ||
f63a8daa PZ |
1295 | static void perf_event_ctx_unlock(struct perf_event *event, |
1296 | struct perf_event_context *ctx) | |
1297 | { | |
1298 | mutex_unlock(&ctx->mutex); | |
1299 | put_ctx(ctx); | |
1300 | } | |
1301 | ||
211de6eb PZ |
1302 | /* |
1303 | * This must be done under the ctx->lock, such as to serialize against | |
1304 | * context_equiv(), therefore we cannot call put_ctx() since that might end up | |
1305 | * calling scheduler related locks and ctx->lock nests inside those. | |
1306 | */ | |
1307 | static __must_check struct perf_event_context * | |
1308 | unclone_ctx(struct perf_event_context *ctx) | |
71a851b4 | 1309 | { |
211de6eb PZ |
1310 | struct perf_event_context *parent_ctx = ctx->parent_ctx; |
1311 | ||
1312 | lockdep_assert_held(&ctx->lock); | |
1313 | ||
1314 | if (parent_ctx) | |
71a851b4 | 1315 | ctx->parent_ctx = NULL; |
5a3126d4 | 1316 | ctx->generation++; |
211de6eb PZ |
1317 | |
1318 | return parent_ctx; | |
71a851b4 PZ |
1319 | } |
1320 | ||
1d953111 ON |
1321 | static u32 perf_event_pid_type(struct perf_event *event, struct task_struct *p, |
1322 | enum pid_type type) | |
6844c09d | 1323 | { |
1d953111 | 1324 | u32 nr; |
6844c09d ACM |
1325 | /* |
1326 | * only top level events have the pid namespace they were created in | |
1327 | */ | |
1328 | if (event->parent) | |
1329 | event = event->parent; | |
1330 | ||
1d953111 ON |
1331 | nr = __task_pid_nr_ns(p, type, event->ns); |
1332 | /* avoid -1 if it is idle thread or runs in another ns */ | |
1333 | if (!nr && !pid_alive(p)) | |
1334 | nr = -1; | |
1335 | return nr; | |
6844c09d ACM |
1336 | } |
1337 | ||
1d953111 | 1338 | static u32 perf_event_pid(struct perf_event *event, struct task_struct *p) |
6844c09d | 1339 | { |
6883f81a | 1340 | return perf_event_pid_type(event, p, PIDTYPE_TGID); |
1d953111 | 1341 | } |
6844c09d | 1342 | |
1d953111 ON |
1343 | static u32 perf_event_tid(struct perf_event *event, struct task_struct *p) |
1344 | { | |
1345 | return perf_event_pid_type(event, p, PIDTYPE_PID); | |
6844c09d ACM |
1346 | } |
1347 | ||
7f453c24 | 1348 | /* |
cdd6c482 | 1349 | * If we inherit events we want to return the parent event id |
7f453c24 PZ |
1350 | * to userspace. |
1351 | */ | |
cdd6c482 | 1352 | static u64 primary_event_id(struct perf_event *event) |
7f453c24 | 1353 | { |
cdd6c482 | 1354 | u64 id = event->id; |
7f453c24 | 1355 | |
cdd6c482 IM |
1356 | if (event->parent) |
1357 | id = event->parent->id; | |
7f453c24 PZ |
1358 | |
1359 | return id; | |
1360 | } | |
1361 | ||
25346b93 | 1362 | /* |
cdd6c482 | 1363 | * Get the perf_event_context for a task and lock it. |
63b6da39 | 1364 | * |
25346b93 PM |
1365 | * This has to cope with with the fact that until it is locked, |
1366 | * the context could get moved to another task. | |
1367 | */ | |
cdd6c482 | 1368 | static struct perf_event_context * |
8dc85d54 | 1369 | perf_lock_task_context(struct task_struct *task, int ctxn, unsigned long *flags) |
25346b93 | 1370 | { |
cdd6c482 | 1371 | struct perf_event_context *ctx; |
25346b93 | 1372 | |
9ed6060d | 1373 | retry: |
058ebd0e PZ |
1374 | /* |
1375 | * One of the few rules of preemptible RCU is that one cannot do | |
1376 | * rcu_read_unlock() while holding a scheduler (or nested) lock when | |
2fd59077 | 1377 | * part of the read side critical section was irqs-enabled -- see |
058ebd0e PZ |
1378 | * rcu_read_unlock_special(). |
1379 | * | |
1380 | * Since ctx->lock nests under rq->lock we must ensure the entire read | |
2fd59077 | 1381 | * side critical section has interrupts disabled. |
058ebd0e | 1382 | */ |
2fd59077 | 1383 | local_irq_save(*flags); |
058ebd0e | 1384 | rcu_read_lock(); |
8dc85d54 | 1385 | ctx = rcu_dereference(task->perf_event_ctxp[ctxn]); |
25346b93 PM |
1386 | if (ctx) { |
1387 | /* | |
1388 | * If this context is a clone of another, it might | |
1389 | * get swapped for another underneath us by | |
cdd6c482 | 1390 | * perf_event_task_sched_out, though the |
25346b93 PM |
1391 | * rcu_read_lock() protects us from any context |
1392 | * getting freed. Lock the context and check if it | |
1393 | * got swapped before we could get the lock, and retry | |
1394 | * if so. If we locked the right context, then it | |
1395 | * can't get swapped on us any more. | |
1396 | */ | |
2fd59077 | 1397 | raw_spin_lock(&ctx->lock); |
8dc85d54 | 1398 | if (ctx != rcu_dereference(task->perf_event_ctxp[ctxn])) { |
2fd59077 | 1399 | raw_spin_unlock(&ctx->lock); |
058ebd0e | 1400 | rcu_read_unlock(); |
2fd59077 | 1401 | local_irq_restore(*flags); |
25346b93 PM |
1402 | goto retry; |
1403 | } | |
b49a9e7e | 1404 | |
63b6da39 | 1405 | if (ctx->task == TASK_TOMBSTONE || |
8c94abbb | 1406 | !refcount_inc_not_zero(&ctx->refcount)) { |
2fd59077 | 1407 | raw_spin_unlock(&ctx->lock); |
b49a9e7e | 1408 | ctx = NULL; |
828b6f0e PZ |
1409 | } else { |
1410 | WARN_ON_ONCE(ctx->task != task); | |
b49a9e7e | 1411 | } |
25346b93 PM |
1412 | } |
1413 | rcu_read_unlock(); | |
2fd59077 PM |
1414 | if (!ctx) |
1415 | local_irq_restore(*flags); | |
25346b93 PM |
1416 | return ctx; |
1417 | } | |
1418 | ||
1419 | /* | |
1420 | * Get the context for a task and increment its pin_count so it | |
1421 | * can't get swapped to another task. This also increments its | |
1422 | * reference count so that the context can't get freed. | |
1423 | */ | |
8dc85d54 PZ |
1424 | static struct perf_event_context * |
1425 | perf_pin_task_context(struct task_struct *task, int ctxn) | |
25346b93 | 1426 | { |
cdd6c482 | 1427 | struct perf_event_context *ctx; |
25346b93 PM |
1428 | unsigned long flags; |
1429 | ||
8dc85d54 | 1430 | ctx = perf_lock_task_context(task, ctxn, &flags); |
25346b93 PM |
1431 | if (ctx) { |
1432 | ++ctx->pin_count; | |
e625cce1 | 1433 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1434 | } |
1435 | return ctx; | |
1436 | } | |
1437 | ||
cdd6c482 | 1438 | static void perf_unpin_context(struct perf_event_context *ctx) |
25346b93 PM |
1439 | { |
1440 | unsigned long flags; | |
1441 | ||
e625cce1 | 1442 | raw_spin_lock_irqsave(&ctx->lock, flags); |
25346b93 | 1443 | --ctx->pin_count; |
e625cce1 | 1444 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1445 | } |
1446 | ||
f67218c3 PZ |
1447 | /* |
1448 | * Update the record of the current time in a context. | |
1449 | */ | |
1450 | static void update_context_time(struct perf_event_context *ctx) | |
1451 | { | |
1452 | u64 now = perf_clock(); | |
1453 | ||
1454 | ctx->time += now - ctx->timestamp; | |
1455 | ctx->timestamp = now; | |
1456 | } | |
1457 | ||
4158755d SE |
1458 | static u64 perf_event_time(struct perf_event *event) |
1459 | { | |
1460 | struct perf_event_context *ctx = event->ctx; | |
e5d1367f SE |
1461 | |
1462 | if (is_cgroup_event(event)) | |
1463 | return perf_cgroup_event_time(event); | |
1464 | ||
4158755d SE |
1465 | return ctx ? ctx->time : 0; |
1466 | } | |
1467 | ||
487f05e1 AS |
1468 | static enum event_type_t get_event_type(struct perf_event *event) |
1469 | { | |
1470 | struct perf_event_context *ctx = event->ctx; | |
1471 | enum event_type_t event_type; | |
1472 | ||
1473 | lockdep_assert_held(&ctx->lock); | |
1474 | ||
3bda69c1 AS |
1475 | /* |
1476 | * It's 'group type', really, because if our group leader is | |
1477 | * pinned, so are we. | |
1478 | */ | |
1479 | if (event->group_leader != event) | |
1480 | event = event->group_leader; | |
1481 | ||
487f05e1 AS |
1482 | event_type = event->attr.pinned ? EVENT_PINNED : EVENT_FLEXIBLE; |
1483 | if (!ctx->task) | |
1484 | event_type |= EVENT_CPU; | |
1485 | ||
1486 | return event_type; | |
1487 | } | |
1488 | ||
8e1a2031 | 1489 | /* |
161c85fa | 1490 | * Helper function to initialize event group nodes. |
8e1a2031 | 1491 | */ |
161c85fa | 1492 | static void init_event_group(struct perf_event *event) |
8e1a2031 AB |
1493 | { |
1494 | RB_CLEAR_NODE(&event->group_node); | |
1495 | event->group_index = 0; | |
1496 | } | |
1497 | ||
1498 | /* | |
1499 | * Extract pinned or flexible groups from the context | |
161c85fa | 1500 | * based on event attrs bits. |
8e1a2031 AB |
1501 | */ |
1502 | static struct perf_event_groups * | |
1503 | get_event_groups(struct perf_event *event, struct perf_event_context *ctx) | |
889ff015 FW |
1504 | { |
1505 | if (event->attr.pinned) | |
1506 | return &ctx->pinned_groups; | |
1507 | else | |
1508 | return &ctx->flexible_groups; | |
1509 | } | |
1510 | ||
8e1a2031 | 1511 | /* |
161c85fa | 1512 | * Helper function to initializes perf_event_group trees. |
8e1a2031 | 1513 | */ |
161c85fa | 1514 | static void perf_event_groups_init(struct perf_event_groups *groups) |
8e1a2031 AB |
1515 | { |
1516 | groups->tree = RB_ROOT; | |
1517 | groups->index = 0; | |
1518 | } | |
1519 | ||
1520 | /* | |
1521 | * Compare function for event groups; | |
161c85fa PZ |
1522 | * |
1523 | * Implements complex key that first sorts by CPU and then by virtual index | |
1524 | * which provides ordering when rotating groups for the same CPU. | |
8e1a2031 | 1525 | */ |
161c85fa PZ |
1526 | static bool |
1527 | perf_event_groups_less(struct perf_event *left, struct perf_event *right) | |
8e1a2031 | 1528 | { |
161c85fa PZ |
1529 | if (left->cpu < right->cpu) |
1530 | return true; | |
1531 | if (left->cpu > right->cpu) | |
1532 | return false; | |
1533 | ||
1534 | if (left->group_index < right->group_index) | |
1535 | return true; | |
1536 | if (left->group_index > right->group_index) | |
1537 | return false; | |
1538 | ||
1539 | return false; | |
8e1a2031 AB |
1540 | } |
1541 | ||
1542 | /* | |
161c85fa PZ |
1543 | * Insert @event into @groups' tree; using {@event->cpu, ++@groups->index} for |
1544 | * key (see perf_event_groups_less). This places it last inside the CPU | |
1545 | * subtree. | |
8e1a2031 AB |
1546 | */ |
1547 | static void | |
1548 | perf_event_groups_insert(struct perf_event_groups *groups, | |
161c85fa | 1549 | struct perf_event *event) |
8e1a2031 AB |
1550 | { |
1551 | struct perf_event *node_event; | |
1552 | struct rb_node *parent; | |
1553 | struct rb_node **node; | |
1554 | ||
1555 | event->group_index = ++groups->index; | |
1556 | ||
1557 | node = &groups->tree.rb_node; | |
1558 | parent = *node; | |
1559 | ||
1560 | while (*node) { | |
1561 | parent = *node; | |
161c85fa | 1562 | node_event = container_of(*node, struct perf_event, group_node); |
8e1a2031 AB |
1563 | |
1564 | if (perf_event_groups_less(event, node_event)) | |
1565 | node = &parent->rb_left; | |
1566 | else | |
1567 | node = &parent->rb_right; | |
1568 | } | |
1569 | ||
1570 | rb_link_node(&event->group_node, parent, node); | |
1571 | rb_insert_color(&event->group_node, &groups->tree); | |
1572 | } | |
1573 | ||
1574 | /* | |
161c85fa | 1575 | * Helper function to insert event into the pinned or flexible groups. |
8e1a2031 AB |
1576 | */ |
1577 | static void | |
1578 | add_event_to_groups(struct perf_event *event, struct perf_event_context *ctx) | |
1579 | { | |
1580 | struct perf_event_groups *groups; | |
1581 | ||
1582 | groups = get_event_groups(event, ctx); | |
1583 | perf_event_groups_insert(groups, event); | |
1584 | } | |
1585 | ||
1586 | /* | |
161c85fa | 1587 | * Delete a group from a tree. |
8e1a2031 AB |
1588 | */ |
1589 | static void | |
1590 | perf_event_groups_delete(struct perf_event_groups *groups, | |
161c85fa | 1591 | struct perf_event *event) |
8e1a2031 | 1592 | { |
161c85fa PZ |
1593 | WARN_ON_ONCE(RB_EMPTY_NODE(&event->group_node) || |
1594 | RB_EMPTY_ROOT(&groups->tree)); | |
8e1a2031 | 1595 | |
161c85fa | 1596 | rb_erase(&event->group_node, &groups->tree); |
8e1a2031 AB |
1597 | init_event_group(event); |
1598 | } | |
1599 | ||
1600 | /* | |
161c85fa | 1601 | * Helper function to delete event from its groups. |
8e1a2031 AB |
1602 | */ |
1603 | static void | |
1604 | del_event_from_groups(struct perf_event *event, struct perf_event_context *ctx) | |
1605 | { | |
1606 | struct perf_event_groups *groups; | |
1607 | ||
1608 | groups = get_event_groups(event, ctx); | |
1609 | perf_event_groups_delete(groups, event); | |
1610 | } | |
1611 | ||
1612 | /* | |
161c85fa | 1613 | * Get the leftmost event in the @cpu subtree. |
8e1a2031 AB |
1614 | */ |
1615 | static struct perf_event * | |
1616 | perf_event_groups_first(struct perf_event_groups *groups, int cpu) | |
1617 | { | |
1618 | struct perf_event *node_event = NULL, *match = NULL; | |
1619 | struct rb_node *node = groups->tree.rb_node; | |
1620 | ||
1621 | while (node) { | |
161c85fa | 1622 | node_event = container_of(node, struct perf_event, group_node); |
8e1a2031 AB |
1623 | |
1624 | if (cpu < node_event->cpu) { | |
1625 | node = node->rb_left; | |
1626 | } else if (cpu > node_event->cpu) { | |
1627 | node = node->rb_right; | |
1628 | } else { | |
1629 | match = node_event; | |
1630 | node = node->rb_left; | |
1631 | } | |
1632 | } | |
1633 | ||
1634 | return match; | |
1635 | } | |
1636 | ||
1cac7b1a PZ |
1637 | /* |
1638 | * Like rb_entry_next_safe() for the @cpu subtree. | |
1639 | */ | |
1640 | static struct perf_event * | |
1641 | perf_event_groups_next(struct perf_event *event) | |
1642 | { | |
1643 | struct perf_event *next; | |
1644 | ||
1645 | next = rb_entry_safe(rb_next(&event->group_node), typeof(*event), group_node); | |
1646 | if (next && next->cpu == event->cpu) | |
1647 | return next; | |
1648 | ||
1649 | return NULL; | |
1650 | } | |
1651 | ||
8e1a2031 | 1652 | /* |
161c85fa | 1653 | * Iterate through the whole groups tree. |
8e1a2031 | 1654 | */ |
6e6804d2 PZ |
1655 | #define perf_event_groups_for_each(event, groups) \ |
1656 | for (event = rb_entry_safe(rb_first(&((groups)->tree)), \ | |
1657 | typeof(*event), group_node); event; \ | |
1658 | event = rb_entry_safe(rb_next(&event->group_node), \ | |
1659 | typeof(*event), group_node)) | |
8e1a2031 | 1660 | |
fccc714b | 1661 | /* |
788faab7 | 1662 | * Add an event from the lists for its context. |
fccc714b PZ |
1663 | * Must be called with ctx->mutex and ctx->lock held. |
1664 | */ | |
04289bb9 | 1665 | static void |
cdd6c482 | 1666 | list_add_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1667 | { |
c994d613 PZ |
1668 | lockdep_assert_held(&ctx->lock); |
1669 | ||
8a49542c PZ |
1670 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); |
1671 | event->attach_state |= PERF_ATTACH_CONTEXT; | |
04289bb9 | 1672 | |
0d3d73aa PZ |
1673 | event->tstamp = perf_event_time(event); |
1674 | ||
04289bb9 | 1675 | /* |
8a49542c PZ |
1676 | * If we're a stand alone event or group leader, we go to the context |
1677 | * list, group events are kept attached to the group so that | |
1678 | * perf_group_detach can, at all times, locate all siblings. | |
04289bb9 | 1679 | */ |
8a49542c | 1680 | if (event->group_leader == event) { |
4ff6a8de | 1681 | event->group_caps = event->event_caps; |
8e1a2031 | 1682 | add_event_to_groups(event, ctx); |
5c148194 | 1683 | } |
592903cd | 1684 | |
db4a8356 | 1685 | list_update_cgroup_event(event, ctx, true); |
e5d1367f | 1686 | |
cdd6c482 IM |
1687 | list_add_rcu(&event->event_entry, &ctx->event_list); |
1688 | ctx->nr_events++; | |
1689 | if (event->attr.inherit_stat) | |
bfbd3381 | 1690 | ctx->nr_stat++; |
5a3126d4 PZ |
1691 | |
1692 | ctx->generation++; | |
04289bb9 IM |
1693 | } |
1694 | ||
0231bb53 JO |
1695 | /* |
1696 | * Initialize event state based on the perf_event_attr::disabled. | |
1697 | */ | |
1698 | static inline void perf_event__state_init(struct perf_event *event) | |
1699 | { | |
1700 | event->state = event->attr.disabled ? PERF_EVENT_STATE_OFF : | |
1701 | PERF_EVENT_STATE_INACTIVE; | |
1702 | } | |
1703 | ||
a723968c | 1704 | static void __perf_event_read_size(struct perf_event *event, int nr_siblings) |
c320c7b7 ACM |
1705 | { |
1706 | int entry = sizeof(u64); /* value */ | |
1707 | int size = 0; | |
1708 | int nr = 1; | |
1709 | ||
1710 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
1711 | size += sizeof(u64); | |
1712 | ||
1713 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
1714 | size += sizeof(u64); | |
1715 | ||
1716 | if (event->attr.read_format & PERF_FORMAT_ID) | |
1717 | entry += sizeof(u64); | |
1718 | ||
1719 | if (event->attr.read_format & PERF_FORMAT_GROUP) { | |
a723968c | 1720 | nr += nr_siblings; |
c320c7b7 ACM |
1721 | size += sizeof(u64); |
1722 | } | |
1723 | ||
1724 | size += entry * nr; | |
1725 | event->read_size = size; | |
1726 | } | |
1727 | ||
a723968c | 1728 | static void __perf_event_header_size(struct perf_event *event, u64 sample_type) |
c320c7b7 ACM |
1729 | { |
1730 | struct perf_sample_data *data; | |
c320c7b7 ACM |
1731 | u16 size = 0; |
1732 | ||
c320c7b7 ACM |
1733 | if (sample_type & PERF_SAMPLE_IP) |
1734 | size += sizeof(data->ip); | |
1735 | ||
6844c09d ACM |
1736 | if (sample_type & PERF_SAMPLE_ADDR) |
1737 | size += sizeof(data->addr); | |
1738 | ||
1739 | if (sample_type & PERF_SAMPLE_PERIOD) | |
1740 | size += sizeof(data->period); | |
1741 | ||
c3feedf2 AK |
1742 | if (sample_type & PERF_SAMPLE_WEIGHT) |
1743 | size += sizeof(data->weight); | |
1744 | ||
6844c09d ACM |
1745 | if (sample_type & PERF_SAMPLE_READ) |
1746 | size += event->read_size; | |
1747 | ||
d6be9ad6 SE |
1748 | if (sample_type & PERF_SAMPLE_DATA_SRC) |
1749 | size += sizeof(data->data_src.val); | |
1750 | ||
fdfbbd07 AK |
1751 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
1752 | size += sizeof(data->txn); | |
1753 | ||
fc7ce9c7 KL |
1754 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) |
1755 | size += sizeof(data->phys_addr); | |
1756 | ||
6844c09d ACM |
1757 | event->header_size = size; |
1758 | } | |
1759 | ||
a723968c PZ |
1760 | /* |
1761 | * Called at perf_event creation and when events are attached/detached from a | |
1762 | * group. | |
1763 | */ | |
1764 | static void perf_event__header_size(struct perf_event *event) | |
1765 | { | |
1766 | __perf_event_read_size(event, | |
1767 | event->group_leader->nr_siblings); | |
1768 | __perf_event_header_size(event, event->attr.sample_type); | |
1769 | } | |
1770 | ||
6844c09d ACM |
1771 | static void perf_event__id_header_size(struct perf_event *event) |
1772 | { | |
1773 | struct perf_sample_data *data; | |
1774 | u64 sample_type = event->attr.sample_type; | |
1775 | u16 size = 0; | |
1776 | ||
c320c7b7 ACM |
1777 | if (sample_type & PERF_SAMPLE_TID) |
1778 | size += sizeof(data->tid_entry); | |
1779 | ||
1780 | if (sample_type & PERF_SAMPLE_TIME) | |
1781 | size += sizeof(data->time); | |
1782 | ||
ff3d527c AH |
1783 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
1784 | size += sizeof(data->id); | |
1785 | ||
c320c7b7 ACM |
1786 | if (sample_type & PERF_SAMPLE_ID) |
1787 | size += sizeof(data->id); | |
1788 | ||
1789 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
1790 | size += sizeof(data->stream_id); | |
1791 | ||
1792 | if (sample_type & PERF_SAMPLE_CPU) | |
1793 | size += sizeof(data->cpu_entry); | |
1794 | ||
6844c09d | 1795 | event->id_header_size = size; |
c320c7b7 ACM |
1796 | } |
1797 | ||
a723968c PZ |
1798 | static bool perf_event_validate_size(struct perf_event *event) |
1799 | { | |
1800 | /* | |
1801 | * The values computed here will be over-written when we actually | |
1802 | * attach the event. | |
1803 | */ | |
1804 | __perf_event_read_size(event, event->group_leader->nr_siblings + 1); | |
1805 | __perf_event_header_size(event, event->attr.sample_type & ~PERF_SAMPLE_READ); | |
1806 | perf_event__id_header_size(event); | |
1807 | ||
1808 | /* | |
1809 | * Sum the lot; should not exceed the 64k limit we have on records. | |
1810 | * Conservative limit to allow for callchains and other variable fields. | |
1811 | */ | |
1812 | if (event->read_size + event->header_size + | |
1813 | event->id_header_size + sizeof(struct perf_event_header) >= 16*1024) | |
1814 | return false; | |
1815 | ||
1816 | return true; | |
1817 | } | |
1818 | ||
8a49542c PZ |
1819 | static void perf_group_attach(struct perf_event *event) |
1820 | { | |
c320c7b7 | 1821 | struct perf_event *group_leader = event->group_leader, *pos; |
8a49542c | 1822 | |
a76a82a3 PZ |
1823 | lockdep_assert_held(&event->ctx->lock); |
1824 | ||
74c3337c PZ |
1825 | /* |
1826 | * We can have double attach due to group movement in perf_event_open. | |
1827 | */ | |
1828 | if (event->attach_state & PERF_ATTACH_GROUP) | |
1829 | return; | |
1830 | ||
8a49542c PZ |
1831 | event->attach_state |= PERF_ATTACH_GROUP; |
1832 | ||
1833 | if (group_leader == event) | |
1834 | return; | |
1835 | ||
652884fe PZ |
1836 | WARN_ON_ONCE(group_leader->ctx != event->ctx); |
1837 | ||
4ff6a8de | 1838 | group_leader->group_caps &= event->event_caps; |
8a49542c | 1839 | |
8343aae6 | 1840 | list_add_tail(&event->sibling_list, &group_leader->sibling_list); |
8a49542c | 1841 | group_leader->nr_siblings++; |
c320c7b7 ACM |
1842 | |
1843 | perf_event__header_size(group_leader); | |
1844 | ||
edb39592 | 1845 | for_each_sibling_event(pos, group_leader) |
c320c7b7 | 1846 | perf_event__header_size(pos); |
8a49542c PZ |
1847 | } |
1848 | ||
a63eaf34 | 1849 | /* |
788faab7 | 1850 | * Remove an event from the lists for its context. |
fccc714b | 1851 | * Must be called with ctx->mutex and ctx->lock held. |
a63eaf34 | 1852 | */ |
04289bb9 | 1853 | static void |
cdd6c482 | 1854 | list_del_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1855 | { |
652884fe PZ |
1856 | WARN_ON_ONCE(event->ctx != ctx); |
1857 | lockdep_assert_held(&ctx->lock); | |
1858 | ||
8a49542c PZ |
1859 | /* |
1860 | * We can have double detach due to exit/hot-unplug + close. | |
1861 | */ | |
1862 | if (!(event->attach_state & PERF_ATTACH_CONTEXT)) | |
a63eaf34 | 1863 | return; |
8a49542c PZ |
1864 | |
1865 | event->attach_state &= ~PERF_ATTACH_CONTEXT; | |
1866 | ||
db4a8356 | 1867 | list_update_cgroup_event(event, ctx, false); |
e5d1367f | 1868 | |
cdd6c482 IM |
1869 | ctx->nr_events--; |
1870 | if (event->attr.inherit_stat) | |
bfbd3381 | 1871 | ctx->nr_stat--; |
8bc20959 | 1872 | |
cdd6c482 | 1873 | list_del_rcu(&event->event_entry); |
04289bb9 | 1874 | |
8a49542c | 1875 | if (event->group_leader == event) |
8e1a2031 | 1876 | del_event_from_groups(event, ctx); |
5c148194 | 1877 | |
b2e74a26 SE |
1878 | /* |
1879 | * If event was in error state, then keep it | |
1880 | * that way, otherwise bogus counts will be | |
1881 | * returned on read(). The only way to get out | |
1882 | * of error state is by explicit re-enabling | |
1883 | * of the event | |
1884 | */ | |
1885 | if (event->state > PERF_EVENT_STATE_OFF) | |
0d3d73aa | 1886 | perf_event_set_state(event, PERF_EVENT_STATE_OFF); |
5a3126d4 PZ |
1887 | |
1888 | ctx->generation++; | |
050735b0 PZ |
1889 | } |
1890 | ||
ab43762e AS |
1891 | static int |
1892 | perf_aux_output_match(struct perf_event *event, struct perf_event *aux_event) | |
1893 | { | |
1894 | if (!has_aux(aux_event)) | |
1895 | return 0; | |
1896 | ||
1897 | if (!event->pmu->aux_output_match) | |
1898 | return 0; | |
1899 | ||
1900 | return event->pmu->aux_output_match(aux_event); | |
1901 | } | |
1902 | ||
1903 | static void put_event(struct perf_event *event); | |
1904 | static void event_sched_out(struct perf_event *event, | |
1905 | struct perf_cpu_context *cpuctx, | |
1906 | struct perf_event_context *ctx); | |
1907 | ||
1908 | static void perf_put_aux_event(struct perf_event *event) | |
1909 | { | |
1910 | struct perf_event_context *ctx = event->ctx; | |
1911 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
1912 | struct perf_event *iter; | |
1913 | ||
1914 | /* | |
1915 | * If event uses aux_event tear down the link | |
1916 | */ | |
1917 | if (event->aux_event) { | |
1918 | iter = event->aux_event; | |
1919 | event->aux_event = NULL; | |
1920 | put_event(iter); | |
1921 | return; | |
1922 | } | |
1923 | ||
1924 | /* | |
1925 | * If the event is an aux_event, tear down all links to | |
1926 | * it from other events. | |
1927 | */ | |
1928 | for_each_sibling_event(iter, event->group_leader) { | |
1929 | if (iter->aux_event != event) | |
1930 | continue; | |
1931 | ||
1932 | iter->aux_event = NULL; | |
1933 | put_event(event); | |
1934 | ||
1935 | /* | |
1936 | * If it's ACTIVE, schedule it out and put it into ERROR | |
1937 | * state so that we don't try to schedule it again. Note | |
1938 | * that perf_event_enable() will clear the ERROR status. | |
1939 | */ | |
1940 | event_sched_out(iter, cpuctx, ctx); | |
1941 | perf_event_set_state(event, PERF_EVENT_STATE_ERROR); | |
1942 | } | |
1943 | } | |
1944 | ||
a4faf00d AS |
1945 | static bool perf_need_aux_event(struct perf_event *event) |
1946 | { | |
1947 | return !!event->attr.aux_output || !!event->attr.aux_sample_size; | |
1948 | } | |
1949 | ||
ab43762e AS |
1950 | static int perf_get_aux_event(struct perf_event *event, |
1951 | struct perf_event *group_leader) | |
1952 | { | |
1953 | /* | |
1954 | * Our group leader must be an aux event if we want to be | |
1955 | * an aux_output. This way, the aux event will precede its | |
1956 | * aux_output events in the group, and therefore will always | |
1957 | * schedule first. | |
1958 | */ | |
1959 | if (!group_leader) | |
1960 | return 0; | |
1961 | ||
a4faf00d AS |
1962 | /* |
1963 | * aux_output and aux_sample_size are mutually exclusive. | |
1964 | */ | |
1965 | if (event->attr.aux_output && event->attr.aux_sample_size) | |
1966 | return 0; | |
1967 | ||
1968 | if (event->attr.aux_output && | |
1969 | !perf_aux_output_match(event, group_leader)) | |
1970 | return 0; | |
1971 | ||
1972 | if (event->attr.aux_sample_size && !group_leader->pmu->snapshot_aux) | |
ab43762e AS |
1973 | return 0; |
1974 | ||
1975 | if (!atomic_long_inc_not_zero(&group_leader->refcount)) | |
1976 | return 0; | |
1977 | ||
1978 | /* | |
1979 | * Link aux_outputs to their aux event; this is undone in | |
1980 | * perf_group_detach() by perf_put_aux_event(). When the | |
1981 | * group in torn down, the aux_output events loose their | |
1982 | * link to the aux_event and can't schedule any more. | |
1983 | */ | |
1984 | event->aux_event = group_leader; | |
1985 | ||
1986 | return 1; | |
1987 | } | |
1988 | ||
ab6f824c PZ |
1989 | static inline struct list_head *get_event_list(struct perf_event *event) |
1990 | { | |
1991 | struct perf_event_context *ctx = event->ctx; | |
1992 | return event->attr.pinned ? &ctx->pinned_active : &ctx->flexible_active; | |
1993 | } | |
1994 | ||
8a49542c | 1995 | static void perf_group_detach(struct perf_event *event) |
050735b0 PZ |
1996 | { |
1997 | struct perf_event *sibling, *tmp; | |
6668128a | 1998 | struct perf_event_context *ctx = event->ctx; |
8a49542c | 1999 | |
6668128a | 2000 | lockdep_assert_held(&ctx->lock); |
a76a82a3 | 2001 | |
8a49542c PZ |
2002 | /* |
2003 | * We can have double detach due to exit/hot-unplug + close. | |
2004 | */ | |
2005 | if (!(event->attach_state & PERF_ATTACH_GROUP)) | |
2006 | return; | |
2007 | ||
2008 | event->attach_state &= ~PERF_ATTACH_GROUP; | |
2009 | ||
ab43762e AS |
2010 | perf_put_aux_event(event); |
2011 | ||
8a49542c PZ |
2012 | /* |
2013 | * If this is a sibling, remove it from its group. | |
2014 | */ | |
2015 | if (event->group_leader != event) { | |
8343aae6 | 2016 | list_del_init(&event->sibling_list); |
8a49542c | 2017 | event->group_leader->nr_siblings--; |
c320c7b7 | 2018 | goto out; |
8a49542c PZ |
2019 | } |
2020 | ||
04289bb9 | 2021 | /* |
cdd6c482 IM |
2022 | * If this was a group event with sibling events then |
2023 | * upgrade the siblings to singleton events by adding them | |
8a49542c | 2024 | * to whatever list we are on. |
04289bb9 | 2025 | */ |
8343aae6 | 2026 | list_for_each_entry_safe(sibling, tmp, &event->sibling_list, sibling_list) { |
8e1a2031 | 2027 | |
04289bb9 | 2028 | sibling->group_leader = sibling; |
24868367 | 2029 | list_del_init(&sibling->sibling_list); |
d6f962b5 FW |
2030 | |
2031 | /* Inherit group flags from the previous leader */ | |
4ff6a8de | 2032 | sibling->group_caps = event->group_caps; |
652884fe | 2033 | |
8e1a2031 | 2034 | if (!RB_EMPTY_NODE(&event->group_node)) { |
8e1a2031 | 2035 | add_event_to_groups(sibling, event->ctx); |
6668128a | 2036 | |
ab6f824c PZ |
2037 | if (sibling->state == PERF_EVENT_STATE_ACTIVE) |
2038 | list_add_tail(&sibling->active_list, get_event_list(sibling)); | |
8e1a2031 AB |
2039 | } |
2040 | ||
652884fe | 2041 | WARN_ON_ONCE(sibling->ctx != event->ctx); |
04289bb9 | 2042 | } |
c320c7b7 ACM |
2043 | |
2044 | out: | |
2045 | perf_event__header_size(event->group_leader); | |
2046 | ||
edb39592 | 2047 | for_each_sibling_event(tmp, event->group_leader) |
c320c7b7 | 2048 | perf_event__header_size(tmp); |
04289bb9 IM |
2049 | } |
2050 | ||
fadfe7be JO |
2051 | static bool is_orphaned_event(struct perf_event *event) |
2052 | { | |
a69b0ca4 | 2053 | return event->state == PERF_EVENT_STATE_DEAD; |
fadfe7be JO |
2054 | } |
2055 | ||
2c81a647 | 2056 | static inline int __pmu_filter_match(struct perf_event *event) |
66eb579e MR |
2057 | { |
2058 | struct pmu *pmu = event->pmu; | |
2059 | return pmu->filter_match ? pmu->filter_match(event) : 1; | |
2060 | } | |
2061 | ||
2c81a647 MR |
2062 | /* |
2063 | * Check whether we should attempt to schedule an event group based on | |
2064 | * PMU-specific filtering. An event group can consist of HW and SW events, | |
2065 | * potentially with a SW leader, so we must check all the filters, to | |
2066 | * determine whether a group is schedulable: | |
2067 | */ | |
2068 | static inline int pmu_filter_match(struct perf_event *event) | |
2069 | { | |
edb39592 | 2070 | struct perf_event *sibling; |
2c81a647 MR |
2071 | |
2072 | if (!__pmu_filter_match(event)) | |
2073 | return 0; | |
2074 | ||
edb39592 PZ |
2075 | for_each_sibling_event(sibling, event) { |
2076 | if (!__pmu_filter_match(sibling)) | |
2c81a647 MR |
2077 | return 0; |
2078 | } | |
2079 | ||
2080 | return 1; | |
2081 | } | |
2082 | ||
fa66f07a SE |
2083 | static inline int |
2084 | event_filter_match(struct perf_event *event) | |
2085 | { | |
0b8f1e2e PZ |
2086 | return (event->cpu == -1 || event->cpu == smp_processor_id()) && |
2087 | perf_cgroup_match(event) && pmu_filter_match(event); | |
fa66f07a SE |
2088 | } |
2089 | ||
9ffcfa6f SE |
2090 | static void |
2091 | event_sched_out(struct perf_event *event, | |
3b6f9e5c | 2092 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 2093 | struct perf_event_context *ctx) |
3b6f9e5c | 2094 | { |
0d3d73aa | 2095 | enum perf_event_state state = PERF_EVENT_STATE_INACTIVE; |
652884fe PZ |
2096 | |
2097 | WARN_ON_ONCE(event->ctx != ctx); | |
2098 | lockdep_assert_held(&ctx->lock); | |
2099 | ||
cdd6c482 | 2100 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
9ffcfa6f | 2101 | return; |
3b6f9e5c | 2102 | |
6668128a PZ |
2103 | /* |
2104 | * Asymmetry; we only schedule events _IN_ through ctx_sched_in(), but | |
2105 | * we can schedule events _OUT_ individually through things like | |
2106 | * __perf_remove_from_context(). | |
2107 | */ | |
2108 | list_del_init(&event->active_list); | |
2109 | ||
44377277 AS |
2110 | perf_pmu_disable(event->pmu); |
2111 | ||
28a967c3 PZ |
2112 | event->pmu->del(event, 0); |
2113 | event->oncpu = -1; | |
0d3d73aa | 2114 | |
1d54ad94 PZ |
2115 | if (READ_ONCE(event->pending_disable) >= 0) { |
2116 | WRITE_ONCE(event->pending_disable, -1); | |
0d3d73aa | 2117 | state = PERF_EVENT_STATE_OFF; |
970892a9 | 2118 | } |
0d3d73aa | 2119 | perf_event_set_state(event, state); |
3b6f9e5c | 2120 | |
cdd6c482 | 2121 | if (!is_software_event(event)) |
3b6f9e5c | 2122 | cpuctx->active_oncpu--; |
2fde4f94 MR |
2123 | if (!--ctx->nr_active) |
2124 | perf_event_ctx_deactivate(ctx); | |
0f5a2601 PZ |
2125 | if (event->attr.freq && event->attr.sample_freq) |
2126 | ctx->nr_freq--; | |
cdd6c482 | 2127 | if (event->attr.exclusive || !cpuctx->active_oncpu) |
3b6f9e5c | 2128 | cpuctx->exclusive = 0; |
44377277 AS |
2129 | |
2130 | perf_pmu_enable(event->pmu); | |
3b6f9e5c PM |
2131 | } |
2132 | ||
d859e29f | 2133 | static void |
cdd6c482 | 2134 | group_sched_out(struct perf_event *group_event, |
d859e29f | 2135 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 2136 | struct perf_event_context *ctx) |
d859e29f | 2137 | { |
cdd6c482 | 2138 | struct perf_event *event; |
0d3d73aa PZ |
2139 | |
2140 | if (group_event->state != PERF_EVENT_STATE_ACTIVE) | |
2141 | return; | |
d859e29f | 2142 | |
3f005e7d MR |
2143 | perf_pmu_disable(ctx->pmu); |
2144 | ||
cdd6c482 | 2145 | event_sched_out(group_event, cpuctx, ctx); |
d859e29f PM |
2146 | |
2147 | /* | |
2148 | * Schedule out siblings (if any): | |
2149 | */ | |
edb39592 | 2150 | for_each_sibling_event(event, group_event) |
cdd6c482 | 2151 | event_sched_out(event, cpuctx, ctx); |
d859e29f | 2152 | |
3f005e7d MR |
2153 | perf_pmu_enable(ctx->pmu); |
2154 | ||
0d3d73aa | 2155 | if (group_event->attr.exclusive) |
d859e29f PM |
2156 | cpuctx->exclusive = 0; |
2157 | } | |
2158 | ||
45a0e07a | 2159 | #define DETACH_GROUP 0x01UL |
0017960f | 2160 | |
0793a61d | 2161 | /* |
cdd6c482 | 2162 | * Cross CPU call to remove a performance event |
0793a61d | 2163 | * |
cdd6c482 | 2164 | * We disable the event on the hardware level first. After that we |
0793a61d TG |
2165 | * remove it from the context list. |
2166 | */ | |
fae3fde6 PZ |
2167 | static void |
2168 | __perf_remove_from_context(struct perf_event *event, | |
2169 | struct perf_cpu_context *cpuctx, | |
2170 | struct perf_event_context *ctx, | |
2171 | void *info) | |
0793a61d | 2172 | { |
45a0e07a | 2173 | unsigned long flags = (unsigned long)info; |
0793a61d | 2174 | |
3c5c8711 PZ |
2175 | if (ctx->is_active & EVENT_TIME) { |
2176 | update_context_time(ctx); | |
2177 | update_cgrp_time_from_cpuctx(cpuctx); | |
2178 | } | |
2179 | ||
cdd6c482 | 2180 | event_sched_out(event, cpuctx, ctx); |
45a0e07a | 2181 | if (flags & DETACH_GROUP) |
46ce0fe9 | 2182 | perf_group_detach(event); |
cdd6c482 | 2183 | list_del_event(event, ctx); |
39a43640 PZ |
2184 | |
2185 | if (!ctx->nr_events && ctx->is_active) { | |
64ce3126 | 2186 | ctx->is_active = 0; |
39a43640 PZ |
2187 | if (ctx->task) { |
2188 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
2189 | cpuctx->task_ctx = NULL; | |
2190 | } | |
64ce3126 | 2191 | } |
0793a61d TG |
2192 | } |
2193 | ||
0793a61d | 2194 | /* |
cdd6c482 | 2195 | * Remove the event from a task's (or a CPU's) list of events. |
0793a61d | 2196 | * |
cdd6c482 IM |
2197 | * If event->ctx is a cloned context, callers must make sure that |
2198 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 PM |
2199 | * remains valid. This is OK when called from perf_release since |
2200 | * that only calls us on the top-level context, which can't be a clone. | |
cdd6c482 | 2201 | * When called from perf_event_exit_task, it's OK because the |
c93f7669 | 2202 | * context has been detached from its task. |
0793a61d | 2203 | */ |
45a0e07a | 2204 | static void perf_remove_from_context(struct perf_event *event, unsigned long flags) |
0793a61d | 2205 | { |
a76a82a3 PZ |
2206 | struct perf_event_context *ctx = event->ctx; |
2207 | ||
2208 | lockdep_assert_held(&ctx->mutex); | |
0793a61d | 2209 | |
45a0e07a | 2210 | event_function_call(event, __perf_remove_from_context, (void *)flags); |
a76a82a3 PZ |
2211 | |
2212 | /* | |
2213 | * The above event_function_call() can NO-OP when it hits | |
2214 | * TASK_TOMBSTONE. In that case we must already have been detached | |
2215 | * from the context (by perf_event_exit_event()) but the grouping | |
2216 | * might still be in-tact. | |
2217 | */ | |
2218 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); | |
2219 | if ((flags & DETACH_GROUP) && | |
2220 | (event->attach_state & PERF_ATTACH_GROUP)) { | |
2221 | /* | |
2222 | * Since in that case we cannot possibly be scheduled, simply | |
2223 | * detach now. | |
2224 | */ | |
2225 | raw_spin_lock_irq(&ctx->lock); | |
2226 | perf_group_detach(event); | |
2227 | raw_spin_unlock_irq(&ctx->lock); | |
2228 | } | |
0793a61d TG |
2229 | } |
2230 | ||
d859e29f | 2231 | /* |
cdd6c482 | 2232 | * Cross CPU call to disable a performance event |
d859e29f | 2233 | */ |
fae3fde6 PZ |
2234 | static void __perf_event_disable(struct perf_event *event, |
2235 | struct perf_cpu_context *cpuctx, | |
2236 | struct perf_event_context *ctx, | |
2237 | void *info) | |
7b648018 | 2238 | { |
fae3fde6 PZ |
2239 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
2240 | return; | |
7b648018 | 2241 | |
3c5c8711 PZ |
2242 | if (ctx->is_active & EVENT_TIME) { |
2243 | update_context_time(ctx); | |
2244 | update_cgrp_time_from_event(event); | |
2245 | } | |
2246 | ||
fae3fde6 PZ |
2247 | if (event == event->group_leader) |
2248 | group_sched_out(event, cpuctx, ctx); | |
2249 | else | |
2250 | event_sched_out(event, cpuctx, ctx); | |
0d3d73aa PZ |
2251 | |
2252 | perf_event_set_state(event, PERF_EVENT_STATE_OFF); | |
7b648018 PZ |
2253 | } |
2254 | ||
d859e29f | 2255 | /* |
788faab7 | 2256 | * Disable an event. |
c93f7669 | 2257 | * |
cdd6c482 IM |
2258 | * If event->ctx is a cloned context, callers must make sure that |
2259 | * every task struct that event->ctx->task could possibly point to | |
9f014e3a | 2260 | * remains valid. This condition is satisfied when called through |
cdd6c482 IM |
2261 | * perf_event_for_each_child or perf_event_for_each because they |
2262 | * hold the top-level event's child_mutex, so any descendant that | |
8ba289b8 PZ |
2263 | * goes to exit will block in perf_event_exit_event(). |
2264 | * | |
cdd6c482 | 2265 | * When called from perf_pending_event it's OK because event->ctx |
c93f7669 | 2266 | * is the current context on this CPU and preemption is disabled, |
cdd6c482 | 2267 | * hence we can't get into perf_event_task_sched_out for this context. |
d859e29f | 2268 | */ |
f63a8daa | 2269 | static void _perf_event_disable(struct perf_event *event) |
d859e29f | 2270 | { |
cdd6c482 | 2271 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 2272 | |
e625cce1 | 2273 | raw_spin_lock_irq(&ctx->lock); |
7b648018 | 2274 | if (event->state <= PERF_EVENT_STATE_OFF) { |
e625cce1 | 2275 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 2276 | return; |
53cfbf59 | 2277 | } |
e625cce1 | 2278 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 2279 | |
fae3fde6 PZ |
2280 | event_function_call(event, __perf_event_disable, NULL); |
2281 | } | |
2282 | ||
2283 | void perf_event_disable_local(struct perf_event *event) | |
2284 | { | |
2285 | event_function_local(event, __perf_event_disable, NULL); | |
d859e29f | 2286 | } |
f63a8daa PZ |
2287 | |
2288 | /* | |
2289 | * Strictly speaking kernel users cannot create groups and therefore this | |
2290 | * interface does not need the perf_event_ctx_lock() magic. | |
2291 | */ | |
2292 | void perf_event_disable(struct perf_event *event) | |
2293 | { | |
2294 | struct perf_event_context *ctx; | |
2295 | ||
2296 | ctx = perf_event_ctx_lock(event); | |
2297 | _perf_event_disable(event); | |
2298 | perf_event_ctx_unlock(event, ctx); | |
2299 | } | |
dcfce4a0 | 2300 | EXPORT_SYMBOL_GPL(perf_event_disable); |
d859e29f | 2301 | |
5aab90ce JO |
2302 | void perf_event_disable_inatomic(struct perf_event *event) |
2303 | { | |
1d54ad94 PZ |
2304 | WRITE_ONCE(event->pending_disable, smp_processor_id()); |
2305 | /* can fail, see perf_pending_event_disable() */ | |
5aab90ce JO |
2306 | irq_work_queue(&event->pending); |
2307 | } | |
2308 | ||
e5d1367f | 2309 | static void perf_set_shadow_time(struct perf_event *event, |
0d3d73aa | 2310 | struct perf_event_context *ctx) |
e5d1367f SE |
2311 | { |
2312 | /* | |
2313 | * use the correct time source for the time snapshot | |
2314 | * | |
2315 | * We could get by without this by leveraging the | |
2316 | * fact that to get to this function, the caller | |
2317 | * has most likely already called update_context_time() | |
2318 | * and update_cgrp_time_xx() and thus both timestamp | |
2319 | * are identical (or very close). Given that tstamp is, | |
2320 | * already adjusted for cgroup, we could say that: | |
2321 | * tstamp - ctx->timestamp | |
2322 | * is equivalent to | |
2323 | * tstamp - cgrp->timestamp. | |
2324 | * | |
2325 | * Then, in perf_output_read(), the calculation would | |
2326 | * work with no changes because: | |
2327 | * - event is guaranteed scheduled in | |
2328 | * - no scheduled out in between | |
2329 | * - thus the timestamp would be the same | |
2330 | * | |
2331 | * But this is a bit hairy. | |
2332 | * | |
2333 | * So instead, we have an explicit cgroup call to remain | |
2334 | * within the time time source all along. We believe it | |
2335 | * is cleaner and simpler to understand. | |
2336 | */ | |
2337 | if (is_cgroup_event(event)) | |
0d3d73aa | 2338 | perf_cgroup_set_shadow_time(event, event->tstamp); |
e5d1367f | 2339 | else |
0d3d73aa | 2340 | event->shadow_ctx_time = event->tstamp - ctx->timestamp; |
e5d1367f SE |
2341 | } |
2342 | ||
4fe757dd PZ |
2343 | #define MAX_INTERRUPTS (~0ULL) |
2344 | ||
2345 | static void perf_log_throttle(struct perf_event *event, int enable); | |
ec0d7729 | 2346 | static void perf_log_itrace_start(struct perf_event *event); |
4fe757dd | 2347 | |
235c7fc7 | 2348 | static int |
9ffcfa6f | 2349 | event_sched_in(struct perf_event *event, |
235c7fc7 | 2350 | struct perf_cpu_context *cpuctx, |
6e37738a | 2351 | struct perf_event_context *ctx) |
235c7fc7 | 2352 | { |
44377277 | 2353 | int ret = 0; |
4158755d | 2354 | |
ab6f824c PZ |
2355 | WARN_ON_ONCE(event->ctx != ctx); |
2356 | ||
63342411 PZ |
2357 | lockdep_assert_held(&ctx->lock); |
2358 | ||
cdd6c482 | 2359 | if (event->state <= PERF_EVENT_STATE_OFF) |
235c7fc7 IM |
2360 | return 0; |
2361 | ||
95ff4ca2 AS |
2362 | WRITE_ONCE(event->oncpu, smp_processor_id()); |
2363 | /* | |
0c1cbc18 PZ |
2364 | * Order event::oncpu write to happen before the ACTIVE state is |
2365 | * visible. This allows perf_event_{stop,read}() to observe the correct | |
2366 | * ->oncpu if it sees ACTIVE. | |
95ff4ca2 AS |
2367 | */ |
2368 | smp_wmb(); | |
0d3d73aa | 2369 | perf_event_set_state(event, PERF_EVENT_STATE_ACTIVE); |
4fe757dd PZ |
2370 | |
2371 | /* | |
2372 | * Unthrottle events, since we scheduled we might have missed several | |
2373 | * ticks already, also for a heavily scheduling task there is little | |
2374 | * guarantee it'll get a tick in a timely manner. | |
2375 | */ | |
2376 | if (unlikely(event->hw.interrupts == MAX_INTERRUPTS)) { | |
2377 | perf_log_throttle(event, 1); | |
2378 | event->hw.interrupts = 0; | |
2379 | } | |
2380 | ||
44377277 AS |
2381 | perf_pmu_disable(event->pmu); |
2382 | ||
0d3d73aa | 2383 | perf_set_shadow_time(event, ctx); |
72f669c0 | 2384 | |
ec0d7729 AS |
2385 | perf_log_itrace_start(event); |
2386 | ||
a4eaf7f1 | 2387 | if (event->pmu->add(event, PERF_EF_START)) { |
0d3d73aa | 2388 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
cdd6c482 | 2389 | event->oncpu = -1; |
44377277 AS |
2390 | ret = -EAGAIN; |
2391 | goto out; | |
235c7fc7 IM |
2392 | } |
2393 | ||
cdd6c482 | 2394 | if (!is_software_event(event)) |
3b6f9e5c | 2395 | cpuctx->active_oncpu++; |
2fde4f94 MR |
2396 | if (!ctx->nr_active++) |
2397 | perf_event_ctx_activate(ctx); | |
0f5a2601 PZ |
2398 | if (event->attr.freq && event->attr.sample_freq) |
2399 | ctx->nr_freq++; | |
235c7fc7 | 2400 | |
cdd6c482 | 2401 | if (event->attr.exclusive) |
3b6f9e5c PM |
2402 | cpuctx->exclusive = 1; |
2403 | ||
44377277 AS |
2404 | out: |
2405 | perf_pmu_enable(event->pmu); | |
2406 | ||
2407 | return ret; | |
235c7fc7 IM |
2408 | } |
2409 | ||
6751b71e | 2410 | static int |
cdd6c482 | 2411 | group_sched_in(struct perf_event *group_event, |
6751b71e | 2412 | struct perf_cpu_context *cpuctx, |
6e37738a | 2413 | struct perf_event_context *ctx) |
6751b71e | 2414 | { |
6bde9b6c | 2415 | struct perf_event *event, *partial_group = NULL; |
4a234593 | 2416 | struct pmu *pmu = ctx->pmu; |
6751b71e | 2417 | |
cdd6c482 | 2418 | if (group_event->state == PERF_EVENT_STATE_OFF) |
6751b71e PM |
2419 | return 0; |
2420 | ||
fbbe0701 | 2421 | pmu->start_txn(pmu, PERF_PMU_TXN_ADD); |
6bde9b6c | 2422 | |
9ffcfa6f | 2423 | if (event_sched_in(group_event, cpuctx, ctx)) { |
ad5133b7 | 2424 | pmu->cancel_txn(pmu); |
272325c4 | 2425 | perf_mux_hrtimer_restart(cpuctx); |
6751b71e | 2426 | return -EAGAIN; |
90151c35 | 2427 | } |
6751b71e PM |
2428 | |
2429 | /* | |
2430 | * Schedule in siblings as one group (if any): | |
2431 | */ | |
edb39592 | 2432 | for_each_sibling_event(event, group_event) { |
9ffcfa6f | 2433 | if (event_sched_in(event, cpuctx, ctx)) { |
cdd6c482 | 2434 | partial_group = event; |
6751b71e PM |
2435 | goto group_error; |
2436 | } | |
2437 | } | |
2438 | ||
9ffcfa6f | 2439 | if (!pmu->commit_txn(pmu)) |
6e85158c | 2440 | return 0; |
9ffcfa6f | 2441 | |
6751b71e PM |
2442 | group_error: |
2443 | /* | |
2444 | * Groups can be scheduled in as one unit only, so undo any | |
2445 | * partial group before returning: | |
0d3d73aa | 2446 | * The events up to the failed event are scheduled out normally. |
6751b71e | 2447 | */ |
edb39592 | 2448 | for_each_sibling_event(event, group_event) { |
cdd6c482 | 2449 | if (event == partial_group) |
0d3d73aa | 2450 | break; |
d7842da4 | 2451 | |
0d3d73aa | 2452 | event_sched_out(event, cpuctx, ctx); |
6751b71e | 2453 | } |
9ffcfa6f | 2454 | event_sched_out(group_event, cpuctx, ctx); |
6751b71e | 2455 | |
ad5133b7 | 2456 | pmu->cancel_txn(pmu); |
90151c35 | 2457 | |
272325c4 | 2458 | perf_mux_hrtimer_restart(cpuctx); |
9e630205 | 2459 | |
6751b71e PM |
2460 | return -EAGAIN; |
2461 | } | |
2462 | ||
3b6f9e5c | 2463 | /* |
cdd6c482 | 2464 | * Work out whether we can put this event group on the CPU now. |
3b6f9e5c | 2465 | */ |
cdd6c482 | 2466 | static int group_can_go_on(struct perf_event *event, |
3b6f9e5c PM |
2467 | struct perf_cpu_context *cpuctx, |
2468 | int can_add_hw) | |
2469 | { | |
2470 | /* | |
cdd6c482 | 2471 | * Groups consisting entirely of software events can always go on. |
3b6f9e5c | 2472 | */ |
4ff6a8de | 2473 | if (event->group_caps & PERF_EV_CAP_SOFTWARE) |
3b6f9e5c PM |
2474 | return 1; |
2475 | /* | |
2476 | * If an exclusive group is already on, no other hardware | |
cdd6c482 | 2477 | * events can go on. |
3b6f9e5c PM |
2478 | */ |
2479 | if (cpuctx->exclusive) | |
2480 | return 0; | |
2481 | /* | |
2482 | * If this group is exclusive and there are already | |
cdd6c482 | 2483 | * events on the CPU, it can't go on. |
3b6f9e5c | 2484 | */ |
cdd6c482 | 2485 | if (event->attr.exclusive && cpuctx->active_oncpu) |
3b6f9e5c PM |
2486 | return 0; |
2487 | /* | |
2488 | * Otherwise, try to add it if all previous groups were able | |
2489 | * to go on. | |
2490 | */ | |
2491 | return can_add_hw; | |
2492 | } | |
2493 | ||
cdd6c482 IM |
2494 | static void add_event_to_ctx(struct perf_event *event, |
2495 | struct perf_event_context *ctx) | |
53cfbf59 | 2496 | { |
cdd6c482 | 2497 | list_add_event(event, ctx); |
8a49542c | 2498 | perf_group_attach(event); |
53cfbf59 PM |
2499 | } |
2500 | ||
bd2afa49 PZ |
2501 | static void ctx_sched_out(struct perf_event_context *ctx, |
2502 | struct perf_cpu_context *cpuctx, | |
2503 | enum event_type_t event_type); | |
2c29ef0f PZ |
2504 | static void |
2505 | ctx_sched_in(struct perf_event_context *ctx, | |
2506 | struct perf_cpu_context *cpuctx, | |
2507 | enum event_type_t event_type, | |
2508 | struct task_struct *task); | |
fe4b04fa | 2509 | |
bd2afa49 | 2510 | static void task_ctx_sched_out(struct perf_cpu_context *cpuctx, |
487f05e1 AS |
2511 | struct perf_event_context *ctx, |
2512 | enum event_type_t event_type) | |
bd2afa49 PZ |
2513 | { |
2514 | if (!cpuctx->task_ctx) | |
2515 | return; | |
2516 | ||
2517 | if (WARN_ON_ONCE(ctx != cpuctx->task_ctx)) | |
2518 | return; | |
2519 | ||
487f05e1 | 2520 | ctx_sched_out(ctx, cpuctx, event_type); |
bd2afa49 PZ |
2521 | } |
2522 | ||
dce5855b PZ |
2523 | static void perf_event_sched_in(struct perf_cpu_context *cpuctx, |
2524 | struct perf_event_context *ctx, | |
2525 | struct task_struct *task) | |
2526 | { | |
2527 | cpu_ctx_sched_in(cpuctx, EVENT_PINNED, task); | |
2528 | if (ctx) | |
2529 | ctx_sched_in(ctx, cpuctx, EVENT_PINNED, task); | |
2530 | cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE, task); | |
2531 | if (ctx) | |
2532 | ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE, task); | |
2533 | } | |
2534 | ||
487f05e1 AS |
2535 | /* |
2536 | * We want to maintain the following priority of scheduling: | |
2537 | * - CPU pinned (EVENT_CPU | EVENT_PINNED) | |
2538 | * - task pinned (EVENT_PINNED) | |
2539 | * - CPU flexible (EVENT_CPU | EVENT_FLEXIBLE) | |
2540 | * - task flexible (EVENT_FLEXIBLE). | |
2541 | * | |
2542 | * In order to avoid unscheduling and scheduling back in everything every | |
2543 | * time an event is added, only do it for the groups of equal priority and | |
2544 | * below. | |
2545 | * | |
2546 | * This can be called after a batch operation on task events, in which case | |
2547 | * event_type is a bit mask of the types of events involved. For CPU events, | |
2548 | * event_type is only either EVENT_PINNED or EVENT_FLEXIBLE. | |
2549 | */ | |
3e349507 | 2550 | static void ctx_resched(struct perf_cpu_context *cpuctx, |
487f05e1 AS |
2551 | struct perf_event_context *task_ctx, |
2552 | enum event_type_t event_type) | |
0017960f | 2553 | { |
bd903afe | 2554 | enum event_type_t ctx_event_type; |
487f05e1 AS |
2555 | bool cpu_event = !!(event_type & EVENT_CPU); |
2556 | ||
2557 | /* | |
2558 | * If pinned groups are involved, flexible groups also need to be | |
2559 | * scheduled out. | |
2560 | */ | |
2561 | if (event_type & EVENT_PINNED) | |
2562 | event_type |= EVENT_FLEXIBLE; | |
2563 | ||
bd903afe SL |
2564 | ctx_event_type = event_type & EVENT_ALL; |
2565 | ||
3e349507 PZ |
2566 | perf_pmu_disable(cpuctx->ctx.pmu); |
2567 | if (task_ctx) | |
487f05e1 AS |
2568 | task_ctx_sched_out(cpuctx, task_ctx, event_type); |
2569 | ||
2570 | /* | |
2571 | * Decide which cpu ctx groups to schedule out based on the types | |
2572 | * of events that caused rescheduling: | |
2573 | * - EVENT_CPU: schedule out corresponding groups; | |
2574 | * - EVENT_PINNED task events: schedule out EVENT_FLEXIBLE groups; | |
2575 | * - otherwise, do nothing more. | |
2576 | */ | |
2577 | if (cpu_event) | |
2578 | cpu_ctx_sched_out(cpuctx, ctx_event_type); | |
2579 | else if (ctx_event_type & EVENT_PINNED) | |
2580 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
2581 | ||
3e349507 PZ |
2582 | perf_event_sched_in(cpuctx, task_ctx, current); |
2583 | perf_pmu_enable(cpuctx->ctx.pmu); | |
0017960f PZ |
2584 | } |
2585 | ||
c68d224e SE |
2586 | void perf_pmu_resched(struct pmu *pmu) |
2587 | { | |
2588 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); | |
2589 | struct perf_event_context *task_ctx = cpuctx->task_ctx; | |
2590 | ||
2591 | perf_ctx_lock(cpuctx, task_ctx); | |
2592 | ctx_resched(cpuctx, task_ctx, EVENT_ALL|EVENT_CPU); | |
2593 | perf_ctx_unlock(cpuctx, task_ctx); | |
2594 | } | |
2595 | ||
0793a61d | 2596 | /* |
cdd6c482 | 2597 | * Cross CPU call to install and enable a performance event |
682076ae | 2598 | * |
a096309b PZ |
2599 | * Very similar to remote_function() + event_function() but cannot assume that |
2600 | * things like ctx->is_active and cpuctx->task_ctx are set. | |
0793a61d | 2601 | */ |
fe4b04fa | 2602 | static int __perf_install_in_context(void *info) |
0793a61d | 2603 | { |
a096309b PZ |
2604 | struct perf_event *event = info; |
2605 | struct perf_event_context *ctx = event->ctx; | |
108b02cf | 2606 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
2c29ef0f | 2607 | struct perf_event_context *task_ctx = cpuctx->task_ctx; |
63cae12b | 2608 | bool reprogram = true; |
a096309b | 2609 | int ret = 0; |
0793a61d | 2610 | |
63b6da39 | 2611 | raw_spin_lock(&cpuctx->ctx.lock); |
39a43640 | 2612 | if (ctx->task) { |
b58f6b0d PZ |
2613 | raw_spin_lock(&ctx->lock); |
2614 | task_ctx = ctx; | |
a096309b | 2615 | |
63cae12b | 2616 | reprogram = (ctx->task == current); |
b58f6b0d | 2617 | |
39a43640 | 2618 | /* |
63cae12b PZ |
2619 | * If the task is running, it must be running on this CPU, |
2620 | * otherwise we cannot reprogram things. | |
2621 | * | |
2622 | * If its not running, we don't care, ctx->lock will | |
2623 | * serialize against it becoming runnable. | |
39a43640 | 2624 | */ |
63cae12b PZ |
2625 | if (task_curr(ctx->task) && !reprogram) { |
2626 | ret = -ESRCH; | |
2627 | goto unlock; | |
2628 | } | |
a096309b | 2629 | |
63cae12b | 2630 | WARN_ON_ONCE(reprogram && cpuctx->task_ctx && cpuctx->task_ctx != ctx); |
63b6da39 PZ |
2631 | } else if (task_ctx) { |
2632 | raw_spin_lock(&task_ctx->lock); | |
2c29ef0f | 2633 | } |
b58f6b0d | 2634 | |
33801b94 | 2635 | #ifdef CONFIG_CGROUP_PERF |
2636 | if (is_cgroup_event(event)) { | |
2637 | /* | |
2638 | * If the current cgroup doesn't match the event's | |
2639 | * cgroup, we should not try to schedule it. | |
2640 | */ | |
2641 | struct perf_cgroup *cgrp = perf_cgroup_from_task(current, ctx); | |
2642 | reprogram = cgroup_is_descendant(cgrp->css.cgroup, | |
2643 | event->cgrp->css.cgroup); | |
2644 | } | |
2645 | #endif | |
2646 | ||
63cae12b | 2647 | if (reprogram) { |
a096309b PZ |
2648 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
2649 | add_event_to_ctx(event, ctx); | |
487f05e1 | 2650 | ctx_resched(cpuctx, task_ctx, get_event_type(event)); |
a096309b PZ |
2651 | } else { |
2652 | add_event_to_ctx(event, ctx); | |
2653 | } | |
2654 | ||
63b6da39 | 2655 | unlock: |
2c29ef0f | 2656 | perf_ctx_unlock(cpuctx, task_ctx); |
fe4b04fa | 2657 | |
a096309b | 2658 | return ret; |
0793a61d TG |
2659 | } |
2660 | ||
8a58ddae AS |
2661 | static bool exclusive_event_installable(struct perf_event *event, |
2662 | struct perf_event_context *ctx); | |
2663 | ||
0793a61d | 2664 | /* |
a096309b PZ |
2665 | * Attach a performance event to a context. |
2666 | * | |
2667 | * Very similar to event_function_call, see comment there. | |
0793a61d TG |
2668 | */ |
2669 | static void | |
cdd6c482 IM |
2670 | perf_install_in_context(struct perf_event_context *ctx, |
2671 | struct perf_event *event, | |
0793a61d TG |
2672 | int cpu) |
2673 | { | |
a096309b | 2674 | struct task_struct *task = READ_ONCE(ctx->task); |
39a43640 | 2675 | |
fe4b04fa PZ |
2676 | lockdep_assert_held(&ctx->mutex); |
2677 | ||
8a58ddae AS |
2678 | WARN_ON_ONCE(!exclusive_event_installable(event, ctx)); |
2679 | ||
0cda4c02 YZ |
2680 | if (event->cpu != -1) |
2681 | event->cpu = cpu; | |
c3f00c70 | 2682 | |
0b8f1e2e PZ |
2683 | /* |
2684 | * Ensures that if we can observe event->ctx, both the event and ctx | |
2685 | * will be 'complete'. See perf_iterate_sb_cpu(). | |
2686 | */ | |
2687 | smp_store_release(&event->ctx, ctx); | |
2688 | ||
db0503e4 PZ |
2689 | /* |
2690 | * perf_event_attr::disabled events will not run and can be initialized | |
2691 | * without IPI. Except when this is the first event for the context, in | |
2692 | * that case we need the magic of the IPI to set ctx->is_active. | |
2693 | * | |
2694 | * The IOC_ENABLE that is sure to follow the creation of a disabled | |
2695 | * event will issue the IPI and reprogram the hardware. | |
2696 | */ | |
2697 | if (__perf_effective_state(event) == PERF_EVENT_STATE_OFF && ctx->nr_events) { | |
2698 | raw_spin_lock_irq(&ctx->lock); | |
2699 | if (ctx->task == TASK_TOMBSTONE) { | |
2700 | raw_spin_unlock_irq(&ctx->lock); | |
2701 | return; | |
2702 | } | |
2703 | add_event_to_ctx(event, ctx); | |
2704 | raw_spin_unlock_irq(&ctx->lock); | |
2705 | return; | |
2706 | } | |
2707 | ||
a096309b PZ |
2708 | if (!task) { |
2709 | cpu_function_call(cpu, __perf_install_in_context, event); | |
2710 | return; | |
2711 | } | |
2712 | ||
2713 | /* | |
2714 | * Should not happen, we validate the ctx is still alive before calling. | |
2715 | */ | |
2716 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) | |
2717 | return; | |
2718 | ||
39a43640 PZ |
2719 | /* |
2720 | * Installing events is tricky because we cannot rely on ctx->is_active | |
2721 | * to be set in case this is the nr_events 0 -> 1 transition. | |
63cae12b PZ |
2722 | * |
2723 | * Instead we use task_curr(), which tells us if the task is running. | |
2724 | * However, since we use task_curr() outside of rq::lock, we can race | |
2725 | * against the actual state. This means the result can be wrong. | |
2726 | * | |
2727 | * If we get a false positive, we retry, this is harmless. | |
2728 | * | |
2729 | * If we get a false negative, things are complicated. If we are after | |
2730 | * perf_event_context_sched_in() ctx::lock will serialize us, and the | |
2731 | * value must be correct. If we're before, it doesn't matter since | |
2732 | * perf_event_context_sched_in() will program the counter. | |
2733 | * | |
2734 | * However, this hinges on the remote context switch having observed | |
2735 | * our task->perf_event_ctxp[] store, such that it will in fact take | |
2736 | * ctx::lock in perf_event_context_sched_in(). | |
2737 | * | |
2738 | * We do this by task_function_call(), if the IPI fails to hit the task | |
2739 | * we know any future context switch of task must see the | |
2740 | * perf_event_ctpx[] store. | |
39a43640 | 2741 | */ |
63cae12b | 2742 | |
63b6da39 | 2743 | /* |
63cae12b PZ |
2744 | * This smp_mb() orders the task->perf_event_ctxp[] store with the |
2745 | * task_cpu() load, such that if the IPI then does not find the task | |
2746 | * running, a future context switch of that task must observe the | |
2747 | * store. | |
63b6da39 | 2748 | */ |
63cae12b PZ |
2749 | smp_mb(); |
2750 | again: | |
2751 | if (!task_function_call(task, __perf_install_in_context, event)) | |
a096309b PZ |
2752 | return; |
2753 | ||
2754 | raw_spin_lock_irq(&ctx->lock); | |
2755 | task = ctx->task; | |
84c4e620 | 2756 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) { |
a096309b PZ |
2757 | /* |
2758 | * Cannot happen because we already checked above (which also | |
2759 | * cannot happen), and we hold ctx->mutex, which serializes us | |
2760 | * against perf_event_exit_task_context(). | |
2761 | */ | |
63b6da39 PZ |
2762 | raw_spin_unlock_irq(&ctx->lock); |
2763 | return; | |
2764 | } | |
39a43640 | 2765 | /* |
63cae12b PZ |
2766 | * If the task is not running, ctx->lock will avoid it becoming so, |
2767 | * thus we can safely install the event. | |
39a43640 | 2768 | */ |
63cae12b PZ |
2769 | if (task_curr(task)) { |
2770 | raw_spin_unlock_irq(&ctx->lock); | |
2771 | goto again; | |
2772 | } | |
2773 | add_event_to_ctx(event, ctx); | |
2774 | raw_spin_unlock_irq(&ctx->lock); | |
0793a61d TG |
2775 | } |
2776 | ||
d859e29f | 2777 | /* |
cdd6c482 | 2778 | * Cross CPU call to enable a performance event |
d859e29f | 2779 | */ |
fae3fde6 PZ |
2780 | static void __perf_event_enable(struct perf_event *event, |
2781 | struct perf_cpu_context *cpuctx, | |
2782 | struct perf_event_context *ctx, | |
2783 | void *info) | |
04289bb9 | 2784 | { |
cdd6c482 | 2785 | struct perf_event *leader = event->group_leader; |
fae3fde6 | 2786 | struct perf_event_context *task_ctx; |
04289bb9 | 2787 | |
6e801e01 PZ |
2788 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2789 | event->state <= PERF_EVENT_STATE_ERROR) | |
fae3fde6 | 2790 | return; |
3cbed429 | 2791 | |
bd2afa49 PZ |
2792 | if (ctx->is_active) |
2793 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); | |
2794 | ||
0d3d73aa | 2795 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
04289bb9 | 2796 | |
fae3fde6 PZ |
2797 | if (!ctx->is_active) |
2798 | return; | |
2799 | ||
e5d1367f | 2800 | if (!event_filter_match(event)) { |
bd2afa49 | 2801 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); |
fae3fde6 | 2802 | return; |
e5d1367f | 2803 | } |
f4c4176f | 2804 | |
04289bb9 | 2805 | /* |
cdd6c482 | 2806 | * If the event is in a group and isn't the group leader, |
d859e29f | 2807 | * then don't put it on unless the group is on. |
04289bb9 | 2808 | */ |
bd2afa49 PZ |
2809 | if (leader != event && leader->state != PERF_EVENT_STATE_ACTIVE) { |
2810 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
fae3fde6 | 2811 | return; |
bd2afa49 | 2812 | } |
fe4b04fa | 2813 | |
fae3fde6 PZ |
2814 | task_ctx = cpuctx->task_ctx; |
2815 | if (ctx->task) | |
2816 | WARN_ON_ONCE(task_ctx != ctx); | |
d859e29f | 2817 | |
487f05e1 | 2818 | ctx_resched(cpuctx, task_ctx, get_event_type(event)); |
7b648018 PZ |
2819 | } |
2820 | ||
d859e29f | 2821 | /* |
788faab7 | 2822 | * Enable an event. |
c93f7669 | 2823 | * |
cdd6c482 IM |
2824 | * If event->ctx is a cloned context, callers must make sure that |
2825 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 2826 | * remains valid. This condition is satisfied when called through |
cdd6c482 IM |
2827 | * perf_event_for_each_child or perf_event_for_each as described |
2828 | * for perf_event_disable. | |
d859e29f | 2829 | */ |
f63a8daa | 2830 | static void _perf_event_enable(struct perf_event *event) |
d859e29f | 2831 | { |
cdd6c482 | 2832 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 2833 | |
7b648018 | 2834 | raw_spin_lock_irq(&ctx->lock); |
6e801e01 PZ |
2835 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2836 | event->state < PERF_EVENT_STATE_ERROR) { | |
7b648018 | 2837 | raw_spin_unlock_irq(&ctx->lock); |
d859e29f PM |
2838 | return; |
2839 | } | |
2840 | ||
d859e29f | 2841 | /* |
cdd6c482 | 2842 | * If the event is in error state, clear that first. |
7b648018 PZ |
2843 | * |
2844 | * That way, if we see the event in error state below, we know that it | |
2845 | * has gone back into error state, as distinct from the task having | |
2846 | * been scheduled away before the cross-call arrived. | |
d859e29f | 2847 | */ |
cdd6c482 IM |
2848 | if (event->state == PERF_EVENT_STATE_ERROR) |
2849 | event->state = PERF_EVENT_STATE_OFF; | |
e625cce1 | 2850 | raw_spin_unlock_irq(&ctx->lock); |
fe4b04fa | 2851 | |
fae3fde6 | 2852 | event_function_call(event, __perf_event_enable, NULL); |
d859e29f | 2853 | } |
f63a8daa PZ |
2854 | |
2855 | /* | |
2856 | * See perf_event_disable(); | |
2857 | */ | |
2858 | void perf_event_enable(struct perf_event *event) | |
2859 | { | |
2860 | struct perf_event_context *ctx; | |
2861 | ||
2862 | ctx = perf_event_ctx_lock(event); | |
2863 | _perf_event_enable(event); | |
2864 | perf_event_ctx_unlock(event, ctx); | |
2865 | } | |
dcfce4a0 | 2866 | EXPORT_SYMBOL_GPL(perf_event_enable); |
d859e29f | 2867 | |
375637bc AS |
2868 | struct stop_event_data { |
2869 | struct perf_event *event; | |
2870 | unsigned int restart; | |
2871 | }; | |
2872 | ||
95ff4ca2 AS |
2873 | static int __perf_event_stop(void *info) |
2874 | { | |
375637bc AS |
2875 | struct stop_event_data *sd = info; |
2876 | struct perf_event *event = sd->event; | |
95ff4ca2 | 2877 | |
375637bc | 2878 | /* if it's already INACTIVE, do nothing */ |
95ff4ca2 AS |
2879 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) |
2880 | return 0; | |
2881 | ||
2882 | /* matches smp_wmb() in event_sched_in() */ | |
2883 | smp_rmb(); | |
2884 | ||
2885 | /* | |
2886 | * There is a window with interrupts enabled before we get here, | |
2887 | * so we need to check again lest we try to stop another CPU's event. | |
2888 | */ | |
2889 | if (READ_ONCE(event->oncpu) != smp_processor_id()) | |
2890 | return -EAGAIN; | |
2891 | ||
2892 | event->pmu->stop(event, PERF_EF_UPDATE); | |
2893 | ||
375637bc AS |
2894 | /* |
2895 | * May race with the actual stop (through perf_pmu_output_stop()), | |
2896 | * but it is only used for events with AUX ring buffer, and such | |
2897 | * events will refuse to restart because of rb::aux_mmap_count==0, | |
2898 | * see comments in perf_aux_output_begin(). | |
2899 | * | |
788faab7 | 2900 | * Since this is happening on an event-local CPU, no trace is lost |
375637bc AS |
2901 | * while restarting. |
2902 | */ | |
2903 | if (sd->restart) | |
c9bbdd48 | 2904 | event->pmu->start(event, 0); |
375637bc | 2905 | |
95ff4ca2 AS |
2906 | return 0; |
2907 | } | |
2908 | ||
767ae086 | 2909 | static int perf_event_stop(struct perf_event *event, int restart) |
375637bc AS |
2910 | { |
2911 | struct stop_event_data sd = { | |
2912 | .event = event, | |
767ae086 | 2913 | .restart = restart, |
375637bc AS |
2914 | }; |
2915 | int ret = 0; | |
2916 | ||
2917 | do { | |
2918 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) | |
2919 | return 0; | |
2920 | ||
2921 | /* matches smp_wmb() in event_sched_in() */ | |
2922 | smp_rmb(); | |
2923 | ||
2924 | /* | |
2925 | * We only want to restart ACTIVE events, so if the event goes | |
2926 | * inactive here (event->oncpu==-1), there's nothing more to do; | |
2927 | * fall through with ret==-ENXIO. | |
2928 | */ | |
2929 | ret = cpu_function_call(READ_ONCE(event->oncpu), | |
2930 | __perf_event_stop, &sd); | |
2931 | } while (ret == -EAGAIN); | |
2932 | ||
2933 | return ret; | |
2934 | } | |
2935 | ||
2936 | /* | |
2937 | * In order to contain the amount of racy and tricky in the address filter | |
2938 | * configuration management, it is a two part process: | |
2939 | * | |
2940 | * (p1) when userspace mappings change as a result of (1) or (2) or (3) below, | |
2941 | * we update the addresses of corresponding vmas in | |
c60f83b8 | 2942 | * event::addr_filter_ranges array and bump the event::addr_filters_gen; |
375637bc AS |
2943 | * (p2) when an event is scheduled in (pmu::add), it calls |
2944 | * perf_event_addr_filters_sync() which calls pmu::addr_filters_sync() | |
2945 | * if the generation has changed since the previous call. | |
2946 | * | |
2947 | * If (p1) happens while the event is active, we restart it to force (p2). | |
2948 | * | |
2949 | * (1) perf_addr_filters_apply(): adjusting filters' offsets based on | |
2950 | * pre-existing mappings, called once when new filters arrive via SET_FILTER | |
2951 | * ioctl; | |
2952 | * (2) perf_addr_filters_adjust(): adjusting filters' offsets based on newly | |
2953 | * registered mapping, called for every new mmap(), with mm::mmap_sem down | |
2954 | * for reading; | |
2955 | * (3) perf_event_addr_filters_exec(): clearing filters' offsets in the process | |
2956 | * of exec. | |
2957 | */ | |
2958 | void perf_event_addr_filters_sync(struct perf_event *event) | |
2959 | { | |
2960 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
2961 | ||
2962 | if (!has_addr_filter(event)) | |
2963 | return; | |
2964 | ||
2965 | raw_spin_lock(&ifh->lock); | |
2966 | if (event->addr_filters_gen != event->hw.addr_filters_gen) { | |
2967 | event->pmu->addr_filters_sync(event); | |
2968 | event->hw.addr_filters_gen = event->addr_filters_gen; | |
2969 | } | |
2970 | raw_spin_unlock(&ifh->lock); | |
2971 | } | |
2972 | EXPORT_SYMBOL_GPL(perf_event_addr_filters_sync); | |
2973 | ||
f63a8daa | 2974 | static int _perf_event_refresh(struct perf_event *event, int refresh) |
79f14641 | 2975 | { |
2023b359 | 2976 | /* |
cdd6c482 | 2977 | * not supported on inherited events |
2023b359 | 2978 | */ |
2e939d1d | 2979 | if (event->attr.inherit || !is_sampling_event(event)) |
2023b359 PZ |
2980 | return -EINVAL; |
2981 | ||
cdd6c482 | 2982 | atomic_add(refresh, &event->event_limit); |
f63a8daa | 2983 | _perf_event_enable(event); |
2023b359 PZ |
2984 | |
2985 | return 0; | |
79f14641 | 2986 | } |
f63a8daa PZ |
2987 | |
2988 | /* | |
2989 | * See perf_event_disable() | |
2990 | */ | |
2991 | int perf_event_refresh(struct perf_event *event, int refresh) | |
2992 | { | |
2993 | struct perf_event_context *ctx; | |
2994 | int ret; | |
2995 | ||
2996 | ctx = perf_event_ctx_lock(event); | |
2997 | ret = _perf_event_refresh(event, refresh); | |
2998 | perf_event_ctx_unlock(event, ctx); | |
2999 | ||
3000 | return ret; | |
3001 | } | |
26ca5c11 | 3002 | EXPORT_SYMBOL_GPL(perf_event_refresh); |
79f14641 | 3003 | |
32ff77e8 MC |
3004 | static int perf_event_modify_breakpoint(struct perf_event *bp, |
3005 | struct perf_event_attr *attr) | |
3006 | { | |
3007 | int err; | |
3008 | ||
3009 | _perf_event_disable(bp); | |
3010 | ||
3011 | err = modify_user_hw_breakpoint_check(bp, attr, true); | |
32ff77e8 | 3012 | |
bf06278c | 3013 | if (!bp->attr.disabled) |
32ff77e8 | 3014 | _perf_event_enable(bp); |
bf06278c JO |
3015 | |
3016 | return err; | |
32ff77e8 MC |
3017 | } |
3018 | ||
3019 | static int perf_event_modify_attr(struct perf_event *event, | |
3020 | struct perf_event_attr *attr) | |
3021 | { | |
3022 | if (event->attr.type != attr->type) | |
3023 | return -EINVAL; | |
3024 | ||
3025 | switch (event->attr.type) { | |
3026 | case PERF_TYPE_BREAKPOINT: | |
3027 | return perf_event_modify_breakpoint(event, attr); | |
3028 | default: | |
3029 | /* Place holder for future additions. */ | |
3030 | return -EOPNOTSUPP; | |
3031 | } | |
3032 | } | |
3033 | ||
5b0311e1 FW |
3034 | static void ctx_sched_out(struct perf_event_context *ctx, |
3035 | struct perf_cpu_context *cpuctx, | |
3036 | enum event_type_t event_type) | |
235c7fc7 | 3037 | { |
6668128a | 3038 | struct perf_event *event, *tmp; |
db24d33e | 3039 | int is_active = ctx->is_active; |
235c7fc7 | 3040 | |
c994d613 | 3041 | lockdep_assert_held(&ctx->lock); |
235c7fc7 | 3042 | |
39a43640 PZ |
3043 | if (likely(!ctx->nr_events)) { |
3044 | /* | |
3045 | * See __perf_remove_from_context(). | |
3046 | */ | |
3047 | WARN_ON_ONCE(ctx->is_active); | |
3048 | if (ctx->task) | |
3049 | WARN_ON_ONCE(cpuctx->task_ctx); | |
facc4307 | 3050 | return; |
39a43640 PZ |
3051 | } |
3052 | ||
db24d33e | 3053 | ctx->is_active &= ~event_type; |
3cbaa590 PZ |
3054 | if (!(ctx->is_active & EVENT_ALL)) |
3055 | ctx->is_active = 0; | |
3056 | ||
63e30d3e PZ |
3057 | if (ctx->task) { |
3058 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
3059 | if (!ctx->is_active) | |
3060 | cpuctx->task_ctx = NULL; | |
3061 | } | |
facc4307 | 3062 | |
8fdc6539 PZ |
3063 | /* |
3064 | * Always update time if it was set; not only when it changes. | |
3065 | * Otherwise we can 'forget' to update time for any but the last | |
3066 | * context we sched out. For example: | |
3067 | * | |
3068 | * ctx_sched_out(.event_type = EVENT_FLEXIBLE) | |
3069 | * ctx_sched_out(.event_type = EVENT_PINNED) | |
3070 | * | |
3071 | * would only update time for the pinned events. | |
3072 | */ | |
3cbaa590 PZ |
3073 | if (is_active & EVENT_TIME) { |
3074 | /* update (and stop) ctx time */ | |
3075 | update_context_time(ctx); | |
3076 | update_cgrp_time_from_cpuctx(cpuctx); | |
3077 | } | |
3078 | ||
8fdc6539 PZ |
3079 | is_active ^= ctx->is_active; /* changed bits */ |
3080 | ||
3cbaa590 | 3081 | if (!ctx->nr_active || !(is_active & EVENT_ALL)) |
facc4307 | 3082 | return; |
5b0311e1 | 3083 | |
fd7d5517 IR |
3084 | /* |
3085 | * If we had been multiplexing, no rotations are necessary, now no events | |
3086 | * are active. | |
3087 | */ | |
3088 | ctx->rotate_necessary = 0; | |
3089 | ||
075e0b00 | 3090 | perf_pmu_disable(ctx->pmu); |
3cbaa590 | 3091 | if (is_active & EVENT_PINNED) { |
6668128a | 3092 | list_for_each_entry_safe(event, tmp, &ctx->pinned_active, active_list) |
889ff015 | 3093 | group_sched_out(event, cpuctx, ctx); |
9ed6060d | 3094 | } |
889ff015 | 3095 | |
3cbaa590 | 3096 | if (is_active & EVENT_FLEXIBLE) { |
6668128a | 3097 | list_for_each_entry_safe(event, tmp, &ctx->flexible_active, active_list) |
8c9ed8e1 | 3098 | group_sched_out(event, cpuctx, ctx); |
9ed6060d | 3099 | } |
1b9a644f | 3100 | perf_pmu_enable(ctx->pmu); |
235c7fc7 IM |
3101 | } |
3102 | ||
564c2b21 | 3103 | /* |
5a3126d4 PZ |
3104 | * Test whether two contexts are equivalent, i.e. whether they have both been |
3105 | * cloned from the same version of the same context. | |
3106 | * | |
3107 | * Equivalence is measured using a generation number in the context that is | |
3108 | * incremented on each modification to it; see unclone_ctx(), list_add_event() | |
3109 | * and list_del_event(). | |
564c2b21 | 3110 | */ |
cdd6c482 IM |
3111 | static int context_equiv(struct perf_event_context *ctx1, |
3112 | struct perf_event_context *ctx2) | |
564c2b21 | 3113 | { |
211de6eb PZ |
3114 | lockdep_assert_held(&ctx1->lock); |
3115 | lockdep_assert_held(&ctx2->lock); | |
3116 | ||
5a3126d4 PZ |
3117 | /* Pinning disables the swap optimization */ |
3118 | if (ctx1->pin_count || ctx2->pin_count) | |
3119 | return 0; | |
3120 | ||
3121 | /* If ctx1 is the parent of ctx2 */ | |
3122 | if (ctx1 == ctx2->parent_ctx && ctx1->generation == ctx2->parent_gen) | |
3123 | return 1; | |
3124 | ||
3125 | /* If ctx2 is the parent of ctx1 */ | |
3126 | if (ctx1->parent_ctx == ctx2 && ctx1->parent_gen == ctx2->generation) | |
3127 | return 1; | |
3128 | ||
3129 | /* | |
3130 | * If ctx1 and ctx2 have the same parent; we flatten the parent | |
3131 | * hierarchy, see perf_event_init_context(). | |
3132 | */ | |
3133 | if (ctx1->parent_ctx && ctx1->parent_ctx == ctx2->parent_ctx && | |
3134 | ctx1->parent_gen == ctx2->parent_gen) | |
3135 | return 1; | |
3136 | ||
3137 | /* Unmatched */ | |
3138 | return 0; | |
564c2b21 PM |
3139 | } |
3140 | ||
cdd6c482 IM |
3141 | static void __perf_event_sync_stat(struct perf_event *event, |
3142 | struct perf_event *next_event) | |
bfbd3381 PZ |
3143 | { |
3144 | u64 value; | |
3145 | ||
cdd6c482 | 3146 | if (!event->attr.inherit_stat) |
bfbd3381 PZ |
3147 | return; |
3148 | ||
3149 | /* | |
cdd6c482 | 3150 | * Update the event value, we cannot use perf_event_read() |
bfbd3381 PZ |
3151 | * because we're in the middle of a context switch and have IRQs |
3152 | * disabled, which upsets smp_call_function_single(), however | |
cdd6c482 | 3153 | * we know the event must be on the current CPU, therefore we |
bfbd3381 PZ |
3154 | * don't need to use it. |
3155 | */ | |
0d3d73aa | 3156 | if (event->state == PERF_EVENT_STATE_ACTIVE) |
3dbebf15 | 3157 | event->pmu->read(event); |
bfbd3381 | 3158 | |
0d3d73aa | 3159 | perf_event_update_time(event); |
bfbd3381 PZ |
3160 | |
3161 | /* | |
cdd6c482 | 3162 | * In order to keep per-task stats reliable we need to flip the event |
bfbd3381 PZ |
3163 | * values when we flip the contexts. |
3164 | */ | |
e7850595 PZ |
3165 | value = local64_read(&next_event->count); |
3166 | value = local64_xchg(&event->count, value); | |
3167 | local64_set(&next_event->count, value); | |
bfbd3381 | 3168 | |
cdd6c482 IM |
3169 | swap(event->total_time_enabled, next_event->total_time_enabled); |
3170 | swap(event->total_time_running, next_event->total_time_running); | |
19d2e755 | 3171 | |
bfbd3381 | 3172 | /* |
19d2e755 | 3173 | * Since we swizzled the values, update the user visible data too. |
bfbd3381 | 3174 | */ |
cdd6c482 IM |
3175 | perf_event_update_userpage(event); |
3176 | perf_event_update_userpage(next_event); | |
bfbd3381 PZ |
3177 | } |
3178 | ||
cdd6c482 IM |
3179 | static void perf_event_sync_stat(struct perf_event_context *ctx, |
3180 | struct perf_event_context *next_ctx) | |
bfbd3381 | 3181 | { |
cdd6c482 | 3182 | struct perf_event *event, *next_event; |
bfbd3381 PZ |
3183 | |
3184 | if (!ctx->nr_stat) | |
3185 | return; | |
3186 | ||
02ffdbc8 PZ |
3187 | update_context_time(ctx); |
3188 | ||
cdd6c482 IM |
3189 | event = list_first_entry(&ctx->event_list, |
3190 | struct perf_event, event_entry); | |
bfbd3381 | 3191 | |
cdd6c482 IM |
3192 | next_event = list_first_entry(&next_ctx->event_list, |
3193 | struct perf_event, event_entry); | |
bfbd3381 | 3194 | |
cdd6c482 IM |
3195 | while (&event->event_entry != &ctx->event_list && |
3196 | &next_event->event_entry != &next_ctx->event_list) { | |
bfbd3381 | 3197 | |
cdd6c482 | 3198 | __perf_event_sync_stat(event, next_event); |
bfbd3381 | 3199 | |
cdd6c482 IM |
3200 | event = list_next_entry(event, event_entry); |
3201 | next_event = list_next_entry(next_event, event_entry); | |
bfbd3381 PZ |
3202 | } |
3203 | } | |
3204 | ||
fe4b04fa PZ |
3205 | static void perf_event_context_sched_out(struct task_struct *task, int ctxn, |
3206 | struct task_struct *next) | |
0793a61d | 3207 | { |
8dc85d54 | 3208 | struct perf_event_context *ctx = task->perf_event_ctxp[ctxn]; |
cdd6c482 | 3209 | struct perf_event_context *next_ctx; |
5a3126d4 | 3210 | struct perf_event_context *parent, *next_parent; |
108b02cf | 3211 | struct perf_cpu_context *cpuctx; |
c93f7669 | 3212 | int do_switch = 1; |
0793a61d | 3213 | |
108b02cf PZ |
3214 | if (likely(!ctx)) |
3215 | return; | |
10989fb2 | 3216 | |
108b02cf PZ |
3217 | cpuctx = __get_cpu_context(ctx); |
3218 | if (!cpuctx->task_ctx) | |
0793a61d TG |
3219 | return; |
3220 | ||
c93f7669 | 3221 | rcu_read_lock(); |
8dc85d54 | 3222 | next_ctx = next->perf_event_ctxp[ctxn]; |
5a3126d4 PZ |
3223 | if (!next_ctx) |
3224 | goto unlock; | |
3225 | ||
3226 | parent = rcu_dereference(ctx->parent_ctx); | |
3227 | next_parent = rcu_dereference(next_ctx->parent_ctx); | |
3228 | ||
3229 | /* If neither context have a parent context; they cannot be clones. */ | |
802c8a61 | 3230 | if (!parent && !next_parent) |
5a3126d4 PZ |
3231 | goto unlock; |
3232 | ||
3233 | if (next_parent == ctx || next_ctx == parent || next_parent == parent) { | |
c93f7669 PM |
3234 | /* |
3235 | * Looks like the two contexts are clones, so we might be | |
3236 | * able to optimize the context switch. We lock both | |
3237 | * contexts and check that they are clones under the | |
3238 | * lock (including re-checking that neither has been | |
3239 | * uncloned in the meantime). It doesn't matter which | |
3240 | * order we take the locks because no other cpu could | |
3241 | * be trying to lock both of these tasks. | |
3242 | */ | |
e625cce1 TG |
3243 | raw_spin_lock(&ctx->lock); |
3244 | raw_spin_lock_nested(&next_ctx->lock, SINGLE_DEPTH_NESTING); | |
c93f7669 | 3245 | if (context_equiv(ctx, next_ctx)) { |
c2b98a86 AB |
3246 | struct pmu *pmu = ctx->pmu; |
3247 | ||
63b6da39 PZ |
3248 | WRITE_ONCE(ctx->task, next); |
3249 | WRITE_ONCE(next_ctx->task, task); | |
5a158c3c | 3250 | |
c2b98a86 AB |
3251 | /* |
3252 | * PMU specific parts of task perf context can require | |
3253 | * additional synchronization. As an example of such | |
3254 | * synchronization see implementation details of Intel | |
3255 | * LBR call stack data profiling; | |
3256 | */ | |
3257 | if (pmu->swap_task_ctx) | |
3258 | pmu->swap_task_ctx(ctx, next_ctx); | |
3259 | else | |
3260 | swap(ctx->task_ctx_data, next_ctx->task_ctx_data); | |
5a158c3c | 3261 | |
63b6da39 PZ |
3262 | /* |
3263 | * RCU_INIT_POINTER here is safe because we've not | |
3264 | * modified the ctx and the above modification of | |
3265 | * ctx->task and ctx->task_ctx_data are immaterial | |
3266 | * since those values are always verified under | |
3267 | * ctx->lock which we're now holding. | |
3268 | */ | |
3269 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], next_ctx); | |
3270 | RCU_INIT_POINTER(next->perf_event_ctxp[ctxn], ctx); | |
3271 | ||
c93f7669 | 3272 | do_switch = 0; |
bfbd3381 | 3273 | |
cdd6c482 | 3274 | perf_event_sync_stat(ctx, next_ctx); |
c93f7669 | 3275 | } |
e625cce1 TG |
3276 | raw_spin_unlock(&next_ctx->lock); |
3277 | raw_spin_unlock(&ctx->lock); | |
564c2b21 | 3278 | } |
5a3126d4 | 3279 | unlock: |
c93f7669 | 3280 | rcu_read_unlock(); |
564c2b21 | 3281 | |
c93f7669 | 3282 | if (do_switch) { |
facc4307 | 3283 | raw_spin_lock(&ctx->lock); |
487f05e1 | 3284 | task_ctx_sched_out(cpuctx, ctx, EVENT_ALL); |
facc4307 | 3285 | raw_spin_unlock(&ctx->lock); |
c93f7669 | 3286 | } |
0793a61d TG |
3287 | } |
3288 | ||
e48c1788 PZ |
3289 | static DEFINE_PER_CPU(struct list_head, sched_cb_list); |
3290 | ||
ba532500 YZ |
3291 | void perf_sched_cb_dec(struct pmu *pmu) |
3292 | { | |
e48c1788 PZ |
3293 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
3294 | ||
ba532500 | 3295 | this_cpu_dec(perf_sched_cb_usages); |
e48c1788 PZ |
3296 | |
3297 | if (!--cpuctx->sched_cb_usage) | |
3298 | list_del(&cpuctx->sched_cb_entry); | |
ba532500 YZ |
3299 | } |
3300 | ||
e48c1788 | 3301 | |
ba532500 YZ |
3302 | void perf_sched_cb_inc(struct pmu *pmu) |
3303 | { | |
e48c1788 PZ |
3304 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
3305 | ||
3306 | if (!cpuctx->sched_cb_usage++) | |
3307 | list_add(&cpuctx->sched_cb_entry, this_cpu_ptr(&sched_cb_list)); | |
3308 | ||
ba532500 YZ |
3309 | this_cpu_inc(perf_sched_cb_usages); |
3310 | } | |
3311 | ||
3312 | /* | |
3313 | * This function provides the context switch callback to the lower code | |
3314 | * layer. It is invoked ONLY when the context switch callback is enabled. | |
09e61b4f PZ |
3315 | * |
3316 | * This callback is relevant even to per-cpu events; for example multi event | |
3317 | * PEBS requires this to provide PID/TID information. This requires we flush | |
3318 | * all queued PEBS records before we context switch to a new task. | |
ba532500 YZ |
3319 | */ |
3320 | static void perf_pmu_sched_task(struct task_struct *prev, | |
3321 | struct task_struct *next, | |
3322 | bool sched_in) | |
3323 | { | |
3324 | struct perf_cpu_context *cpuctx; | |
3325 | struct pmu *pmu; | |
ba532500 YZ |
3326 | |
3327 | if (prev == next) | |
3328 | return; | |
3329 | ||
e48c1788 | 3330 | list_for_each_entry(cpuctx, this_cpu_ptr(&sched_cb_list), sched_cb_entry) { |
1fd7e416 | 3331 | pmu = cpuctx->ctx.pmu; /* software PMUs will not have sched_task */ |
ba532500 | 3332 | |
e48c1788 PZ |
3333 | if (WARN_ON_ONCE(!pmu->sched_task)) |
3334 | continue; | |
ba532500 | 3335 | |
e48c1788 PZ |
3336 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
3337 | perf_pmu_disable(pmu); | |
ba532500 | 3338 | |
e48c1788 | 3339 | pmu->sched_task(cpuctx->task_ctx, sched_in); |
ba532500 | 3340 | |
e48c1788 PZ |
3341 | perf_pmu_enable(pmu); |
3342 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
ba532500 | 3343 | } |
ba532500 YZ |
3344 | } |
3345 | ||
45ac1403 AH |
3346 | static void perf_event_switch(struct task_struct *task, |
3347 | struct task_struct *next_prev, bool sched_in); | |
3348 | ||
8dc85d54 PZ |
3349 | #define for_each_task_context_nr(ctxn) \ |
3350 | for ((ctxn) = 0; (ctxn) < perf_nr_task_contexts; (ctxn)++) | |
3351 | ||
3352 | /* | |
3353 | * Called from scheduler to remove the events of the current task, | |
3354 | * with interrupts disabled. | |
3355 | * | |
3356 | * We stop each event and update the event value in event->count. | |
3357 | * | |
3358 | * This does not protect us against NMI, but disable() | |
3359 | * sets the disabled bit in the control field of event _before_ | |
3360 | * accessing the event control register. If a NMI hits, then it will | |
3361 | * not restart the event. | |
3362 | */ | |
ab0cce56 JO |
3363 | void __perf_event_task_sched_out(struct task_struct *task, |
3364 | struct task_struct *next) | |
8dc85d54 PZ |
3365 | { |
3366 | int ctxn; | |
3367 | ||
ba532500 YZ |
3368 | if (__this_cpu_read(perf_sched_cb_usages)) |
3369 | perf_pmu_sched_task(task, next, false); | |
3370 | ||
45ac1403 AH |
3371 | if (atomic_read(&nr_switch_events)) |
3372 | perf_event_switch(task, next, false); | |
3373 | ||
8dc85d54 PZ |
3374 | for_each_task_context_nr(ctxn) |
3375 | perf_event_context_sched_out(task, ctxn, next); | |
e5d1367f SE |
3376 | |
3377 | /* | |
3378 | * if cgroup events exist on this CPU, then we need | |
3379 | * to check if we have to switch out PMU state. | |
3380 | * cgroup event are system-wide mode only | |
3381 | */ | |
4a32fea9 | 3382 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) |
a8d757ef | 3383 | perf_cgroup_sched_out(task, next); |
8dc85d54 PZ |
3384 | } |
3385 | ||
5b0311e1 FW |
3386 | /* |
3387 | * Called with IRQs disabled | |
3388 | */ | |
3389 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, | |
3390 | enum event_type_t event_type) | |
3391 | { | |
3392 | ctx_sched_out(&cpuctx->ctx, cpuctx, event_type); | |
04289bb9 IM |
3393 | } |
3394 | ||
1cac7b1a PZ |
3395 | static int visit_groups_merge(struct perf_event_groups *groups, int cpu, |
3396 | int (*func)(struct perf_event *, void *), void *data) | |
0793a61d | 3397 | { |
1cac7b1a PZ |
3398 | struct perf_event **evt, *evt1, *evt2; |
3399 | int ret; | |
8e1a2031 | 3400 | |
1cac7b1a PZ |
3401 | evt1 = perf_event_groups_first(groups, -1); |
3402 | evt2 = perf_event_groups_first(groups, cpu); | |
3403 | ||
3404 | while (evt1 || evt2) { | |
3405 | if (evt1 && evt2) { | |
3406 | if (evt1->group_index < evt2->group_index) | |
3407 | evt = &evt1; | |
3408 | else | |
3409 | evt = &evt2; | |
3410 | } else if (evt1) { | |
3411 | evt = &evt1; | |
3412 | } else { | |
3413 | evt = &evt2; | |
8e1a2031 | 3414 | } |
1cac7b1a PZ |
3415 | |
3416 | ret = func(*evt, data); | |
3417 | if (ret) | |
3418 | return ret; | |
3419 | ||
3420 | *evt = perf_event_groups_next(*evt); | |
8e1a2031 | 3421 | } |
0793a61d | 3422 | |
1cac7b1a PZ |
3423 | return 0; |
3424 | } | |
3425 | ||
3426 | struct sched_in_data { | |
3427 | struct perf_event_context *ctx; | |
3428 | struct perf_cpu_context *cpuctx; | |
3429 | int can_add_hw; | |
3430 | }; | |
3431 | ||
ab6f824c | 3432 | static int merge_sched_in(struct perf_event *event, void *data) |
1cac7b1a PZ |
3433 | { |
3434 | struct sched_in_data *sid = data; | |
3435 | ||
ab6f824c PZ |
3436 | WARN_ON_ONCE(event->ctx != sid->ctx); |
3437 | ||
1cac7b1a PZ |
3438 | if (event->state <= PERF_EVENT_STATE_OFF) |
3439 | return 0; | |
3440 | ||
3441 | if (!event_filter_match(event)) | |
3442 | return 0; | |
3443 | ||
6668128a PZ |
3444 | if (group_can_go_on(event, sid->cpuctx, sid->can_add_hw)) { |
3445 | if (!group_sched_in(event, sid->cpuctx, sid->ctx)) | |
ab6f824c | 3446 | list_add_tail(&event->active_list, get_event_list(event)); |
6668128a | 3447 | } |
1cac7b1a | 3448 | |
ab6f824c PZ |
3449 | if (event->state == PERF_EVENT_STATE_INACTIVE) { |
3450 | if (event->attr.pinned) | |
3451 | perf_event_set_state(event, PERF_EVENT_STATE_ERROR); | |
1cac7b1a | 3452 | |
ab6f824c PZ |
3453 | sid->can_add_hw = 0; |
3454 | sid->ctx->rotate_necessary = 1; | |
3b6f9e5c | 3455 | } |
1cac7b1a PZ |
3456 | |
3457 | return 0; | |
5b0311e1 FW |
3458 | } |
3459 | ||
3460 | static void | |
1cac7b1a PZ |
3461 | ctx_pinned_sched_in(struct perf_event_context *ctx, |
3462 | struct perf_cpu_context *cpuctx) | |
5b0311e1 | 3463 | { |
1cac7b1a PZ |
3464 | struct sched_in_data sid = { |
3465 | .ctx = ctx, | |
3466 | .cpuctx = cpuctx, | |
3467 | .can_add_hw = 1, | |
3468 | }; | |
3b6f9e5c | 3469 | |
1cac7b1a PZ |
3470 | visit_groups_merge(&ctx->pinned_groups, |
3471 | smp_processor_id(), | |
ab6f824c | 3472 | merge_sched_in, &sid); |
1cac7b1a | 3473 | } |
8e1a2031 | 3474 | |
1cac7b1a PZ |
3475 | static void |
3476 | ctx_flexible_sched_in(struct perf_event_context *ctx, | |
3477 | struct perf_cpu_context *cpuctx) | |
3478 | { | |
3479 | struct sched_in_data sid = { | |
3480 | .ctx = ctx, | |
3481 | .cpuctx = cpuctx, | |
3482 | .can_add_hw = 1, | |
3483 | }; | |
0793a61d | 3484 | |
1cac7b1a PZ |
3485 | visit_groups_merge(&ctx->flexible_groups, |
3486 | smp_processor_id(), | |
ab6f824c | 3487 | merge_sched_in, &sid); |
5b0311e1 FW |
3488 | } |
3489 | ||
3490 | static void | |
3491 | ctx_sched_in(struct perf_event_context *ctx, | |
3492 | struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
3493 | enum event_type_t event_type, |
3494 | struct task_struct *task) | |
5b0311e1 | 3495 | { |
db24d33e | 3496 | int is_active = ctx->is_active; |
c994d613 PZ |
3497 | u64 now; |
3498 | ||
3499 | lockdep_assert_held(&ctx->lock); | |
e5d1367f | 3500 | |
5b0311e1 | 3501 | if (likely(!ctx->nr_events)) |
facc4307 | 3502 | return; |
5b0311e1 | 3503 | |
3cbaa590 | 3504 | ctx->is_active |= (event_type | EVENT_TIME); |
63e30d3e PZ |
3505 | if (ctx->task) { |
3506 | if (!is_active) | |
3507 | cpuctx->task_ctx = ctx; | |
3508 | else | |
3509 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
3510 | } | |
3511 | ||
3cbaa590 PZ |
3512 | is_active ^= ctx->is_active; /* changed bits */ |
3513 | ||
3514 | if (is_active & EVENT_TIME) { | |
3515 | /* start ctx time */ | |
3516 | now = perf_clock(); | |
3517 | ctx->timestamp = now; | |
3518 | perf_cgroup_set_timestamp(task, ctx); | |
3519 | } | |
3520 | ||
5b0311e1 FW |
3521 | /* |
3522 | * First go through the list and put on any pinned groups | |
3523 | * in order to give them the best chance of going on. | |
3524 | */ | |
3cbaa590 | 3525 | if (is_active & EVENT_PINNED) |
6e37738a | 3526 | ctx_pinned_sched_in(ctx, cpuctx); |
5b0311e1 FW |
3527 | |
3528 | /* Then walk through the lower prio flexible groups */ | |
3cbaa590 | 3529 | if (is_active & EVENT_FLEXIBLE) |
6e37738a | 3530 | ctx_flexible_sched_in(ctx, cpuctx); |
235c7fc7 IM |
3531 | } |
3532 | ||
329c0e01 | 3533 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, |
e5d1367f SE |
3534 | enum event_type_t event_type, |
3535 | struct task_struct *task) | |
329c0e01 FW |
3536 | { |
3537 | struct perf_event_context *ctx = &cpuctx->ctx; | |
3538 | ||
e5d1367f | 3539 | ctx_sched_in(ctx, cpuctx, event_type, task); |
329c0e01 FW |
3540 | } |
3541 | ||
e5d1367f SE |
3542 | static void perf_event_context_sched_in(struct perf_event_context *ctx, |
3543 | struct task_struct *task) | |
235c7fc7 | 3544 | { |
108b02cf | 3545 | struct perf_cpu_context *cpuctx; |
235c7fc7 | 3546 | |
108b02cf | 3547 | cpuctx = __get_cpu_context(ctx); |
329c0e01 FW |
3548 | if (cpuctx->task_ctx == ctx) |
3549 | return; | |
3550 | ||
facc4307 | 3551 | perf_ctx_lock(cpuctx, ctx); |
fdccc3fb | 3552 | /* |
3553 | * We must check ctx->nr_events while holding ctx->lock, such | |
3554 | * that we serialize against perf_install_in_context(). | |
3555 | */ | |
3556 | if (!ctx->nr_events) | |
3557 | goto unlock; | |
3558 | ||
1b9a644f | 3559 | perf_pmu_disable(ctx->pmu); |
329c0e01 FW |
3560 | /* |
3561 | * We want to keep the following priority order: | |
3562 | * cpu pinned (that don't need to move), task pinned, | |
3563 | * cpu flexible, task flexible. | |
fe45bafb AS |
3564 | * |
3565 | * However, if task's ctx is not carrying any pinned | |
3566 | * events, no need to flip the cpuctx's events around. | |
329c0e01 | 3567 | */ |
8e1a2031 | 3568 | if (!RB_EMPTY_ROOT(&ctx->pinned_groups.tree)) |
fe45bafb | 3569 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); |
63e30d3e | 3570 | perf_event_sched_in(cpuctx, ctx, task); |
facc4307 | 3571 | perf_pmu_enable(ctx->pmu); |
fdccc3fb | 3572 | |
3573 | unlock: | |
facc4307 | 3574 | perf_ctx_unlock(cpuctx, ctx); |
235c7fc7 IM |
3575 | } |
3576 | ||
8dc85d54 PZ |
3577 | /* |
3578 | * Called from scheduler to add the events of the current task | |
3579 | * with interrupts disabled. | |
3580 | * | |
3581 | * We restore the event value and then enable it. | |
3582 | * | |
3583 | * This does not protect us against NMI, but enable() | |
3584 | * sets the enabled bit in the control field of event _before_ | |
3585 | * accessing the event control register. If a NMI hits, then it will | |
3586 | * keep the event running. | |
3587 | */ | |
ab0cce56 JO |
3588 | void __perf_event_task_sched_in(struct task_struct *prev, |
3589 | struct task_struct *task) | |
8dc85d54 PZ |
3590 | { |
3591 | struct perf_event_context *ctx; | |
3592 | int ctxn; | |
3593 | ||
7e41d177 PZ |
3594 | /* |
3595 | * If cgroup events exist on this CPU, then we need to check if we have | |
3596 | * to switch in PMU state; cgroup event are system-wide mode only. | |
3597 | * | |
3598 | * Since cgroup events are CPU events, we must schedule these in before | |
3599 | * we schedule in the task events. | |
3600 | */ | |
3601 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) | |
3602 | perf_cgroup_sched_in(prev, task); | |
3603 | ||
8dc85d54 PZ |
3604 | for_each_task_context_nr(ctxn) { |
3605 | ctx = task->perf_event_ctxp[ctxn]; | |
3606 | if (likely(!ctx)) | |
3607 | continue; | |
3608 | ||
e5d1367f | 3609 | perf_event_context_sched_in(ctx, task); |
8dc85d54 | 3610 | } |
d010b332 | 3611 | |
45ac1403 AH |
3612 | if (atomic_read(&nr_switch_events)) |
3613 | perf_event_switch(task, prev, true); | |
3614 | ||
ba532500 YZ |
3615 | if (__this_cpu_read(perf_sched_cb_usages)) |
3616 | perf_pmu_sched_task(prev, task, true); | |
235c7fc7 IM |
3617 | } |
3618 | ||
abd50713 PZ |
3619 | static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count) |
3620 | { | |
3621 | u64 frequency = event->attr.sample_freq; | |
3622 | u64 sec = NSEC_PER_SEC; | |
3623 | u64 divisor, dividend; | |
3624 | ||
3625 | int count_fls, nsec_fls, frequency_fls, sec_fls; | |
3626 | ||
3627 | count_fls = fls64(count); | |
3628 | nsec_fls = fls64(nsec); | |
3629 | frequency_fls = fls64(frequency); | |
3630 | sec_fls = 30; | |
3631 | ||
3632 | /* | |
3633 | * We got @count in @nsec, with a target of sample_freq HZ | |
3634 | * the target period becomes: | |
3635 | * | |
3636 | * @count * 10^9 | |
3637 | * period = ------------------- | |
3638 | * @nsec * sample_freq | |
3639 | * | |
3640 | */ | |
3641 | ||
3642 | /* | |
3643 | * Reduce accuracy by one bit such that @a and @b converge | |
3644 | * to a similar magnitude. | |
3645 | */ | |
fe4b04fa | 3646 | #define REDUCE_FLS(a, b) \ |
abd50713 PZ |
3647 | do { \ |
3648 | if (a##_fls > b##_fls) { \ | |
3649 | a >>= 1; \ | |
3650 | a##_fls--; \ | |
3651 | } else { \ | |
3652 | b >>= 1; \ | |
3653 | b##_fls--; \ | |
3654 | } \ | |
3655 | } while (0) | |
3656 | ||
3657 | /* | |
3658 | * Reduce accuracy until either term fits in a u64, then proceed with | |
3659 | * the other, so that finally we can do a u64/u64 division. | |
3660 | */ | |
3661 | while (count_fls + sec_fls > 64 && nsec_fls + frequency_fls > 64) { | |
3662 | REDUCE_FLS(nsec, frequency); | |
3663 | REDUCE_FLS(sec, count); | |
3664 | } | |
3665 | ||
3666 | if (count_fls + sec_fls > 64) { | |
3667 | divisor = nsec * frequency; | |
3668 | ||
3669 | while (count_fls + sec_fls > 64) { | |
3670 | REDUCE_FLS(count, sec); | |
3671 | divisor >>= 1; | |
3672 | } | |
3673 | ||
3674 | dividend = count * sec; | |
3675 | } else { | |
3676 | dividend = count * sec; | |
3677 | ||
3678 | while (nsec_fls + frequency_fls > 64) { | |
3679 | REDUCE_FLS(nsec, frequency); | |
3680 | dividend >>= 1; | |
3681 | } | |
3682 | ||
3683 | divisor = nsec * frequency; | |
3684 | } | |
3685 | ||
f6ab91ad PZ |
3686 | if (!divisor) |
3687 | return dividend; | |
3688 | ||
abd50713 PZ |
3689 | return div64_u64(dividend, divisor); |
3690 | } | |
3691 | ||
e050e3f0 SE |
3692 | static DEFINE_PER_CPU(int, perf_throttled_count); |
3693 | static DEFINE_PER_CPU(u64, perf_throttled_seq); | |
3694 | ||
f39d47ff | 3695 | static void perf_adjust_period(struct perf_event *event, u64 nsec, u64 count, bool disable) |
bd2b5b12 | 3696 | { |
cdd6c482 | 3697 | struct hw_perf_event *hwc = &event->hw; |
f6ab91ad | 3698 | s64 period, sample_period; |
bd2b5b12 PZ |
3699 | s64 delta; |
3700 | ||
abd50713 | 3701 | period = perf_calculate_period(event, nsec, count); |
bd2b5b12 PZ |
3702 | |
3703 | delta = (s64)(period - hwc->sample_period); | |
3704 | delta = (delta + 7) / 8; /* low pass filter */ | |
3705 | ||
3706 | sample_period = hwc->sample_period + delta; | |
3707 | ||
3708 | if (!sample_period) | |
3709 | sample_period = 1; | |
3710 | ||
bd2b5b12 | 3711 | hwc->sample_period = sample_period; |
abd50713 | 3712 | |
e7850595 | 3713 | if (local64_read(&hwc->period_left) > 8*sample_period) { |
f39d47ff SE |
3714 | if (disable) |
3715 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3716 | ||
e7850595 | 3717 | local64_set(&hwc->period_left, 0); |
f39d47ff SE |
3718 | |
3719 | if (disable) | |
3720 | event->pmu->start(event, PERF_EF_RELOAD); | |
abd50713 | 3721 | } |
bd2b5b12 PZ |
3722 | } |
3723 | ||
e050e3f0 SE |
3724 | /* |
3725 | * combine freq adjustment with unthrottling to avoid two passes over the | |
3726 | * events. At the same time, make sure, having freq events does not change | |
3727 | * the rate of unthrottling as that would introduce bias. | |
3728 | */ | |
3729 | static void perf_adjust_freq_unthr_context(struct perf_event_context *ctx, | |
3730 | int needs_unthr) | |
60db5e09 | 3731 | { |
cdd6c482 IM |
3732 | struct perf_event *event; |
3733 | struct hw_perf_event *hwc; | |
e050e3f0 | 3734 | u64 now, period = TICK_NSEC; |
abd50713 | 3735 | s64 delta; |
60db5e09 | 3736 | |
e050e3f0 SE |
3737 | /* |
3738 | * only need to iterate over all events iff: | |
3739 | * - context have events in frequency mode (needs freq adjust) | |
3740 | * - there are events to unthrottle on this cpu | |
3741 | */ | |
3742 | if (!(ctx->nr_freq || needs_unthr)) | |
0f5a2601 PZ |
3743 | return; |
3744 | ||
e050e3f0 | 3745 | raw_spin_lock(&ctx->lock); |
f39d47ff | 3746 | perf_pmu_disable(ctx->pmu); |
e050e3f0 | 3747 | |
03541f8b | 3748 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { |
cdd6c482 | 3749 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
60db5e09 PZ |
3750 | continue; |
3751 | ||
5632ab12 | 3752 | if (!event_filter_match(event)) |
5d27c23d PZ |
3753 | continue; |
3754 | ||
44377277 AS |
3755 | perf_pmu_disable(event->pmu); |
3756 | ||
cdd6c482 | 3757 | hwc = &event->hw; |
6a24ed6c | 3758 | |
ae23bff1 | 3759 | if (hwc->interrupts == MAX_INTERRUPTS) { |
e050e3f0 | 3760 | hwc->interrupts = 0; |
cdd6c482 | 3761 | perf_log_throttle(event, 1); |
a4eaf7f1 | 3762 | event->pmu->start(event, 0); |
a78ac325 PZ |
3763 | } |
3764 | ||
cdd6c482 | 3765 | if (!event->attr.freq || !event->attr.sample_freq) |
44377277 | 3766 | goto next; |
60db5e09 | 3767 | |
e050e3f0 SE |
3768 | /* |
3769 | * stop the event and update event->count | |
3770 | */ | |
3771 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3772 | ||
e7850595 | 3773 | now = local64_read(&event->count); |
abd50713 PZ |
3774 | delta = now - hwc->freq_count_stamp; |
3775 | hwc->freq_count_stamp = now; | |
60db5e09 | 3776 | |
e050e3f0 SE |
3777 | /* |
3778 | * restart the event | |
3779 | * reload only if value has changed | |
f39d47ff SE |
3780 | * we have stopped the event so tell that |
3781 | * to perf_adjust_period() to avoid stopping it | |
3782 | * twice. | |
e050e3f0 | 3783 | */ |
abd50713 | 3784 | if (delta > 0) |
f39d47ff | 3785 | perf_adjust_period(event, period, delta, false); |
e050e3f0 SE |
3786 | |
3787 | event->pmu->start(event, delta > 0 ? PERF_EF_RELOAD : 0); | |
44377277 AS |
3788 | next: |
3789 | perf_pmu_enable(event->pmu); | |
60db5e09 | 3790 | } |
e050e3f0 | 3791 | |
f39d47ff | 3792 | perf_pmu_enable(ctx->pmu); |
e050e3f0 | 3793 | raw_spin_unlock(&ctx->lock); |
60db5e09 PZ |
3794 | } |
3795 | ||
235c7fc7 | 3796 | /* |
8703a7cf | 3797 | * Move @event to the tail of the @ctx's elegible events. |
235c7fc7 | 3798 | */ |
8703a7cf | 3799 | static void rotate_ctx(struct perf_event_context *ctx, struct perf_event *event) |
0793a61d | 3800 | { |
dddd3379 TG |
3801 | /* |
3802 | * Rotate the first entry last of non-pinned groups. Rotation might be | |
3803 | * disabled by the inheritance code. | |
3804 | */ | |
8703a7cf PZ |
3805 | if (ctx->rotate_disable) |
3806 | return; | |
8e1a2031 | 3807 | |
8703a7cf PZ |
3808 | perf_event_groups_delete(&ctx->flexible_groups, event); |
3809 | perf_event_groups_insert(&ctx->flexible_groups, event); | |
235c7fc7 IM |
3810 | } |
3811 | ||
7fa343b7 | 3812 | /* pick an event from the flexible_groups to rotate */ |
8d5bce0c | 3813 | static inline struct perf_event * |
7fa343b7 | 3814 | ctx_event_to_rotate(struct perf_event_context *ctx) |
235c7fc7 | 3815 | { |
7fa343b7 SL |
3816 | struct perf_event *event; |
3817 | ||
3818 | /* pick the first active flexible event */ | |
3819 | event = list_first_entry_or_null(&ctx->flexible_active, | |
3820 | struct perf_event, active_list); | |
3821 | ||
3822 | /* if no active flexible event, pick the first event */ | |
3823 | if (!event) { | |
3824 | event = rb_entry_safe(rb_first(&ctx->flexible_groups.tree), | |
3825 | typeof(*event), group_node); | |
3826 | } | |
3827 | ||
3828 | return event; | |
8d5bce0c PZ |
3829 | } |
3830 | ||
3831 | static bool perf_rotate_context(struct perf_cpu_context *cpuctx) | |
3832 | { | |
3833 | struct perf_event *cpu_event = NULL, *task_event = NULL; | |
fd7d5517 IR |
3834 | struct perf_event_context *task_ctx = NULL; |
3835 | int cpu_rotate, task_rotate; | |
8d5bce0c PZ |
3836 | |
3837 | /* | |
3838 | * Since we run this from IRQ context, nobody can install new | |
3839 | * events, thus the event count values are stable. | |
3840 | */ | |
7fc23a53 | 3841 | |
fd7d5517 IR |
3842 | cpu_rotate = cpuctx->ctx.rotate_necessary; |
3843 | task_ctx = cpuctx->task_ctx; | |
3844 | task_rotate = task_ctx ? task_ctx->rotate_necessary : 0; | |
9717e6cd | 3845 | |
8d5bce0c PZ |
3846 | if (!(cpu_rotate || task_rotate)) |
3847 | return false; | |
0f5a2601 | 3848 | |
facc4307 | 3849 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
1b9a644f | 3850 | perf_pmu_disable(cpuctx->ctx.pmu); |
60db5e09 | 3851 | |
8d5bce0c | 3852 | if (task_rotate) |
7fa343b7 | 3853 | task_event = ctx_event_to_rotate(task_ctx); |
8d5bce0c | 3854 | if (cpu_rotate) |
7fa343b7 | 3855 | cpu_event = ctx_event_to_rotate(&cpuctx->ctx); |
8703a7cf | 3856 | |
8d5bce0c PZ |
3857 | /* |
3858 | * As per the order given at ctx_resched() first 'pop' task flexible | |
3859 | * and then, if needed CPU flexible. | |
3860 | */ | |
fd7d5517 IR |
3861 | if (task_event || (task_ctx && cpu_event)) |
3862 | ctx_sched_out(task_ctx, cpuctx, EVENT_FLEXIBLE); | |
8d5bce0c PZ |
3863 | if (cpu_event) |
3864 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
0793a61d | 3865 | |
8d5bce0c | 3866 | if (task_event) |
fd7d5517 | 3867 | rotate_ctx(task_ctx, task_event); |
8d5bce0c PZ |
3868 | if (cpu_event) |
3869 | rotate_ctx(&cpuctx->ctx, cpu_event); | |
235c7fc7 | 3870 | |
fd7d5517 | 3871 | perf_event_sched_in(cpuctx, task_ctx, current); |
235c7fc7 | 3872 | |
0f5a2601 PZ |
3873 | perf_pmu_enable(cpuctx->ctx.pmu); |
3874 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
9e630205 | 3875 | |
8d5bce0c | 3876 | return true; |
e9d2b064 PZ |
3877 | } |
3878 | ||
3879 | void perf_event_task_tick(void) | |
3880 | { | |
2fde4f94 MR |
3881 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
3882 | struct perf_event_context *ctx, *tmp; | |
e050e3f0 | 3883 | int throttled; |
b5ab4cd5 | 3884 | |
16444645 | 3885 | lockdep_assert_irqs_disabled(); |
e9d2b064 | 3886 | |
e050e3f0 SE |
3887 | __this_cpu_inc(perf_throttled_seq); |
3888 | throttled = __this_cpu_xchg(perf_throttled_count, 0); | |
555e0c1e | 3889 | tick_dep_clear_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
e050e3f0 | 3890 | |
2fde4f94 | 3891 | list_for_each_entry_safe(ctx, tmp, head, active_ctx_list) |
e050e3f0 | 3892 | perf_adjust_freq_unthr_context(ctx, throttled); |
0793a61d TG |
3893 | } |
3894 | ||
889ff015 FW |
3895 | static int event_enable_on_exec(struct perf_event *event, |
3896 | struct perf_event_context *ctx) | |
3897 | { | |
3898 | if (!event->attr.enable_on_exec) | |
3899 | return 0; | |
3900 | ||
3901 | event->attr.enable_on_exec = 0; | |
3902 | if (event->state >= PERF_EVENT_STATE_INACTIVE) | |
3903 | return 0; | |
3904 | ||
0d3d73aa | 3905 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
889ff015 FW |
3906 | |
3907 | return 1; | |
3908 | } | |
3909 | ||
57e7986e | 3910 | /* |
cdd6c482 | 3911 | * Enable all of a task's events that have been marked enable-on-exec. |
57e7986e PM |
3912 | * This expects task == current. |
3913 | */ | |
c1274499 | 3914 | static void perf_event_enable_on_exec(int ctxn) |
57e7986e | 3915 | { |
c1274499 | 3916 | struct perf_event_context *ctx, *clone_ctx = NULL; |
487f05e1 | 3917 | enum event_type_t event_type = 0; |
3e349507 | 3918 | struct perf_cpu_context *cpuctx; |
cdd6c482 | 3919 | struct perf_event *event; |
57e7986e PM |
3920 | unsigned long flags; |
3921 | int enabled = 0; | |
3922 | ||
3923 | local_irq_save(flags); | |
c1274499 | 3924 | ctx = current->perf_event_ctxp[ctxn]; |
cdd6c482 | 3925 | if (!ctx || !ctx->nr_events) |
57e7986e PM |
3926 | goto out; |
3927 | ||
3e349507 PZ |
3928 | cpuctx = __get_cpu_context(ctx); |
3929 | perf_ctx_lock(cpuctx, ctx); | |
7fce2509 | 3930 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
487f05e1 | 3931 | list_for_each_entry(event, &ctx->event_list, event_entry) { |
3e349507 | 3932 | enabled |= event_enable_on_exec(event, ctx); |
487f05e1 AS |
3933 | event_type |= get_event_type(event); |
3934 | } | |
57e7986e PM |
3935 | |
3936 | /* | |
3e349507 | 3937 | * Unclone and reschedule this context if we enabled any event. |
57e7986e | 3938 | */ |
3e349507 | 3939 | if (enabled) { |
211de6eb | 3940 | clone_ctx = unclone_ctx(ctx); |
487f05e1 | 3941 | ctx_resched(cpuctx, ctx, event_type); |
7bbba0eb PZ |
3942 | } else { |
3943 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
3e349507 PZ |
3944 | } |
3945 | perf_ctx_unlock(cpuctx, ctx); | |
57e7986e | 3946 | |
9ed6060d | 3947 | out: |
57e7986e | 3948 | local_irq_restore(flags); |
211de6eb PZ |
3949 | |
3950 | if (clone_ctx) | |
3951 | put_ctx(clone_ctx); | |
57e7986e PM |
3952 | } |
3953 | ||
0492d4c5 PZ |
3954 | struct perf_read_data { |
3955 | struct perf_event *event; | |
3956 | bool group; | |
7d88962e | 3957 | int ret; |
0492d4c5 PZ |
3958 | }; |
3959 | ||
451d24d1 | 3960 | static int __perf_event_read_cpu(struct perf_event *event, int event_cpu) |
d6a2f903 | 3961 | { |
d6a2f903 DCC |
3962 | u16 local_pkg, event_pkg; |
3963 | ||
3964 | if (event->group_caps & PERF_EV_CAP_READ_ACTIVE_PKG) { | |
451d24d1 PZ |
3965 | int local_cpu = smp_processor_id(); |
3966 | ||
3967 | event_pkg = topology_physical_package_id(event_cpu); | |
3968 | local_pkg = topology_physical_package_id(local_cpu); | |
d6a2f903 DCC |
3969 | |
3970 | if (event_pkg == local_pkg) | |
3971 | return local_cpu; | |
3972 | } | |
3973 | ||
3974 | return event_cpu; | |
3975 | } | |
3976 | ||
0793a61d | 3977 | /* |
cdd6c482 | 3978 | * Cross CPU call to read the hardware event |
0793a61d | 3979 | */ |
cdd6c482 | 3980 | static void __perf_event_read(void *info) |
0793a61d | 3981 | { |
0492d4c5 PZ |
3982 | struct perf_read_data *data = info; |
3983 | struct perf_event *sub, *event = data->event; | |
cdd6c482 | 3984 | struct perf_event_context *ctx = event->ctx; |
108b02cf | 3985 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
4a00c16e | 3986 | struct pmu *pmu = event->pmu; |
621a01ea | 3987 | |
e1ac3614 PM |
3988 | /* |
3989 | * If this is a task context, we need to check whether it is | |
3990 | * the current task context of this cpu. If not it has been | |
3991 | * scheduled out before the smp call arrived. In that case | |
cdd6c482 IM |
3992 | * event->count would have been updated to a recent sample |
3993 | * when the event was scheduled out. | |
e1ac3614 PM |
3994 | */ |
3995 | if (ctx->task && cpuctx->task_ctx != ctx) | |
3996 | return; | |
3997 | ||
e625cce1 | 3998 | raw_spin_lock(&ctx->lock); |
0c1cbc18 | 3999 | if (ctx->is_active & EVENT_TIME) { |
542e72fc | 4000 | update_context_time(ctx); |
e5d1367f SE |
4001 | update_cgrp_time_from_event(event); |
4002 | } | |
0492d4c5 | 4003 | |
0d3d73aa PZ |
4004 | perf_event_update_time(event); |
4005 | if (data->group) | |
4006 | perf_event_update_sibling_time(event); | |
0c1cbc18 | 4007 | |
4a00c16e SB |
4008 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
4009 | goto unlock; | |
0492d4c5 | 4010 | |
4a00c16e SB |
4011 | if (!data->group) { |
4012 | pmu->read(event); | |
4013 | data->ret = 0; | |
0492d4c5 | 4014 | goto unlock; |
4a00c16e SB |
4015 | } |
4016 | ||
4017 | pmu->start_txn(pmu, PERF_PMU_TXN_READ); | |
4018 | ||
4019 | pmu->read(event); | |
0492d4c5 | 4020 | |
edb39592 | 4021 | for_each_sibling_event(sub, event) { |
4a00c16e SB |
4022 | if (sub->state == PERF_EVENT_STATE_ACTIVE) { |
4023 | /* | |
4024 | * Use sibling's PMU rather than @event's since | |
4025 | * sibling could be on different (eg: software) PMU. | |
4026 | */ | |
0492d4c5 | 4027 | sub->pmu->read(sub); |
4a00c16e | 4028 | } |
0492d4c5 | 4029 | } |
4a00c16e SB |
4030 | |
4031 | data->ret = pmu->commit_txn(pmu); | |
0492d4c5 PZ |
4032 | |
4033 | unlock: | |
e625cce1 | 4034 | raw_spin_unlock(&ctx->lock); |
0793a61d TG |
4035 | } |
4036 | ||
b5e58793 PZ |
4037 | static inline u64 perf_event_count(struct perf_event *event) |
4038 | { | |
c39a0e2c | 4039 | return local64_read(&event->count) + atomic64_read(&event->child_count); |
b5e58793 PZ |
4040 | } |
4041 | ||
ffe8690c KX |
4042 | /* |
4043 | * NMI-safe method to read a local event, that is an event that | |
4044 | * is: | |
4045 | * - either for the current task, or for this CPU | |
4046 | * - does not have inherit set, for inherited task events | |
4047 | * will not be local and we cannot read them atomically | |
4048 | * - must not have a pmu::count method | |
4049 | */ | |
7d9285e8 YS |
4050 | int perf_event_read_local(struct perf_event *event, u64 *value, |
4051 | u64 *enabled, u64 *running) | |
ffe8690c KX |
4052 | { |
4053 | unsigned long flags; | |
f91840a3 | 4054 | int ret = 0; |
ffe8690c KX |
4055 | |
4056 | /* | |
4057 | * Disabling interrupts avoids all counter scheduling (context | |
4058 | * switches, timer based rotation and IPIs). | |
4059 | */ | |
4060 | local_irq_save(flags); | |
4061 | ||
ffe8690c KX |
4062 | /* |
4063 | * It must not be an event with inherit set, we cannot read | |
4064 | * all child counters from atomic context. | |
4065 | */ | |
f91840a3 AS |
4066 | if (event->attr.inherit) { |
4067 | ret = -EOPNOTSUPP; | |
4068 | goto out; | |
4069 | } | |
ffe8690c | 4070 | |
f91840a3 AS |
4071 | /* If this is a per-task event, it must be for current */ |
4072 | if ((event->attach_state & PERF_ATTACH_TASK) && | |
4073 | event->hw.target != current) { | |
4074 | ret = -EINVAL; | |
4075 | goto out; | |
4076 | } | |
4077 | ||
4078 | /* If this is a per-CPU event, it must be for this CPU */ | |
4079 | if (!(event->attach_state & PERF_ATTACH_TASK) && | |
4080 | event->cpu != smp_processor_id()) { | |
4081 | ret = -EINVAL; | |
4082 | goto out; | |
4083 | } | |
ffe8690c | 4084 | |
befb1b3c RC |
4085 | /* If this is a pinned event it must be running on this CPU */ |
4086 | if (event->attr.pinned && event->oncpu != smp_processor_id()) { | |
4087 | ret = -EBUSY; | |
4088 | goto out; | |
4089 | } | |
4090 | ||
ffe8690c KX |
4091 | /* |
4092 | * If the event is currently on this CPU, its either a per-task event, | |
4093 | * or local to this CPU. Furthermore it means its ACTIVE (otherwise | |
4094 | * oncpu == -1). | |
4095 | */ | |
4096 | if (event->oncpu == smp_processor_id()) | |
4097 | event->pmu->read(event); | |
4098 | ||
f91840a3 | 4099 | *value = local64_read(&event->count); |
0d3d73aa PZ |
4100 | if (enabled || running) { |
4101 | u64 now = event->shadow_ctx_time + perf_clock(); | |
4102 | u64 __enabled, __running; | |
4103 | ||
4104 | __perf_update_times(event, now, &__enabled, &__running); | |
4105 | if (enabled) | |
4106 | *enabled = __enabled; | |
4107 | if (running) | |
4108 | *running = __running; | |
4109 | } | |
f91840a3 | 4110 | out: |
ffe8690c KX |
4111 | local_irq_restore(flags); |
4112 | ||
f91840a3 | 4113 | return ret; |
ffe8690c KX |
4114 | } |
4115 | ||
7d88962e | 4116 | static int perf_event_read(struct perf_event *event, bool group) |
0793a61d | 4117 | { |
0c1cbc18 | 4118 | enum perf_event_state state = READ_ONCE(event->state); |
451d24d1 | 4119 | int event_cpu, ret = 0; |
7d88962e | 4120 | |
0793a61d | 4121 | /* |
cdd6c482 IM |
4122 | * If event is enabled and currently active on a CPU, update the |
4123 | * value in the event structure: | |
0793a61d | 4124 | */ |
0c1cbc18 PZ |
4125 | again: |
4126 | if (state == PERF_EVENT_STATE_ACTIVE) { | |
4127 | struct perf_read_data data; | |
4128 | ||
4129 | /* | |
4130 | * Orders the ->state and ->oncpu loads such that if we see | |
4131 | * ACTIVE we must also see the right ->oncpu. | |
4132 | * | |
4133 | * Matches the smp_wmb() from event_sched_in(). | |
4134 | */ | |
4135 | smp_rmb(); | |
d6a2f903 | 4136 | |
451d24d1 PZ |
4137 | event_cpu = READ_ONCE(event->oncpu); |
4138 | if ((unsigned)event_cpu >= nr_cpu_ids) | |
4139 | return 0; | |
4140 | ||
0c1cbc18 PZ |
4141 | data = (struct perf_read_data){ |
4142 | .event = event, | |
4143 | .group = group, | |
4144 | .ret = 0, | |
4145 | }; | |
4146 | ||
451d24d1 PZ |
4147 | preempt_disable(); |
4148 | event_cpu = __perf_event_read_cpu(event, event_cpu); | |
d6a2f903 | 4149 | |
58763148 PZ |
4150 | /* |
4151 | * Purposely ignore the smp_call_function_single() return | |
4152 | * value. | |
4153 | * | |
451d24d1 | 4154 | * If event_cpu isn't a valid CPU it means the event got |
58763148 PZ |
4155 | * scheduled out and that will have updated the event count. |
4156 | * | |
4157 | * Therefore, either way, we'll have an up-to-date event count | |
4158 | * after this. | |
4159 | */ | |
451d24d1 PZ |
4160 | (void)smp_call_function_single(event_cpu, __perf_event_read, &data, 1); |
4161 | preempt_enable(); | |
58763148 | 4162 | ret = data.ret; |
0c1cbc18 PZ |
4163 | |
4164 | } else if (state == PERF_EVENT_STATE_INACTIVE) { | |
2b8988c9 PZ |
4165 | struct perf_event_context *ctx = event->ctx; |
4166 | unsigned long flags; | |
4167 | ||
e625cce1 | 4168 | raw_spin_lock_irqsave(&ctx->lock, flags); |
0c1cbc18 PZ |
4169 | state = event->state; |
4170 | if (state != PERF_EVENT_STATE_INACTIVE) { | |
4171 | raw_spin_unlock_irqrestore(&ctx->lock, flags); | |
4172 | goto again; | |
4173 | } | |
4174 | ||
c530ccd9 | 4175 | /* |
0c1cbc18 PZ |
4176 | * May read while context is not active (e.g., thread is |
4177 | * blocked), in that case we cannot update context time | |
c530ccd9 | 4178 | */ |
0c1cbc18 | 4179 | if (ctx->is_active & EVENT_TIME) { |
c530ccd9 | 4180 | update_context_time(ctx); |
e5d1367f SE |
4181 | update_cgrp_time_from_event(event); |
4182 | } | |
0c1cbc18 | 4183 | |
0d3d73aa | 4184 | perf_event_update_time(event); |
0492d4c5 | 4185 | if (group) |
0d3d73aa | 4186 | perf_event_update_sibling_time(event); |
e625cce1 | 4187 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
0793a61d | 4188 | } |
7d88962e SB |
4189 | |
4190 | return ret; | |
0793a61d TG |
4191 | } |
4192 | ||
a63eaf34 | 4193 | /* |
cdd6c482 | 4194 | * Initialize the perf_event context in a task_struct: |
a63eaf34 | 4195 | */ |
eb184479 | 4196 | static void __perf_event_init_context(struct perf_event_context *ctx) |
a63eaf34 | 4197 | { |
e625cce1 | 4198 | raw_spin_lock_init(&ctx->lock); |
a63eaf34 | 4199 | mutex_init(&ctx->mutex); |
2fde4f94 | 4200 | INIT_LIST_HEAD(&ctx->active_ctx_list); |
8e1a2031 AB |
4201 | perf_event_groups_init(&ctx->pinned_groups); |
4202 | perf_event_groups_init(&ctx->flexible_groups); | |
a63eaf34 | 4203 | INIT_LIST_HEAD(&ctx->event_list); |
6668128a PZ |
4204 | INIT_LIST_HEAD(&ctx->pinned_active); |
4205 | INIT_LIST_HEAD(&ctx->flexible_active); | |
8c94abbb | 4206 | refcount_set(&ctx->refcount, 1); |
eb184479 PZ |
4207 | } |
4208 | ||
4209 | static struct perf_event_context * | |
4210 | alloc_perf_context(struct pmu *pmu, struct task_struct *task) | |
4211 | { | |
4212 | struct perf_event_context *ctx; | |
4213 | ||
4214 | ctx = kzalloc(sizeof(struct perf_event_context), GFP_KERNEL); | |
4215 | if (!ctx) | |
4216 | return NULL; | |
4217 | ||
4218 | __perf_event_init_context(ctx); | |
7b3c92b8 MWO |
4219 | if (task) |
4220 | ctx->task = get_task_struct(task); | |
eb184479 PZ |
4221 | ctx->pmu = pmu; |
4222 | ||
4223 | return ctx; | |
a63eaf34 PM |
4224 | } |
4225 | ||
2ebd4ffb MH |
4226 | static struct task_struct * |
4227 | find_lively_task_by_vpid(pid_t vpid) | |
4228 | { | |
4229 | struct task_struct *task; | |
0793a61d TG |
4230 | |
4231 | rcu_read_lock(); | |
2ebd4ffb | 4232 | if (!vpid) |
0793a61d TG |
4233 | task = current; |
4234 | else | |
2ebd4ffb | 4235 | task = find_task_by_vpid(vpid); |
0793a61d TG |
4236 | if (task) |
4237 | get_task_struct(task); | |
4238 | rcu_read_unlock(); | |
4239 | ||
4240 | if (!task) | |
4241 | return ERR_PTR(-ESRCH); | |
4242 | ||
2ebd4ffb | 4243 | return task; |
2ebd4ffb MH |
4244 | } |
4245 | ||
fe4b04fa PZ |
4246 | /* |
4247 | * Returns a matching context with refcount and pincount. | |
4248 | */ | |
108b02cf | 4249 | static struct perf_event_context * |
4af57ef2 YZ |
4250 | find_get_context(struct pmu *pmu, struct task_struct *task, |
4251 | struct perf_event *event) | |
0793a61d | 4252 | { |
211de6eb | 4253 | struct perf_event_context *ctx, *clone_ctx = NULL; |
22a4f650 | 4254 | struct perf_cpu_context *cpuctx; |
4af57ef2 | 4255 | void *task_ctx_data = NULL; |
25346b93 | 4256 | unsigned long flags; |
8dc85d54 | 4257 | int ctxn, err; |
4af57ef2 | 4258 | int cpu = event->cpu; |
0793a61d | 4259 | |
22a4ec72 | 4260 | if (!task) { |
cdd6c482 | 4261 | /* Must be root to operate on a CPU event: */ |
da97e184 JFG |
4262 | err = perf_allow_cpu(&event->attr); |
4263 | if (err) | |
4264 | return ERR_PTR(err); | |
0793a61d | 4265 | |
108b02cf | 4266 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); |
0793a61d | 4267 | ctx = &cpuctx->ctx; |
c93f7669 | 4268 | get_ctx(ctx); |
fe4b04fa | 4269 | ++ctx->pin_count; |
0793a61d | 4270 | |
0793a61d TG |
4271 | return ctx; |
4272 | } | |
4273 | ||
8dc85d54 PZ |
4274 | err = -EINVAL; |
4275 | ctxn = pmu->task_ctx_nr; | |
4276 | if (ctxn < 0) | |
4277 | goto errout; | |
4278 | ||
4af57ef2 YZ |
4279 | if (event->attach_state & PERF_ATTACH_TASK_DATA) { |
4280 | task_ctx_data = kzalloc(pmu->task_ctx_size, GFP_KERNEL); | |
4281 | if (!task_ctx_data) { | |
4282 | err = -ENOMEM; | |
4283 | goto errout; | |
4284 | } | |
4285 | } | |
4286 | ||
9ed6060d | 4287 | retry: |
8dc85d54 | 4288 | ctx = perf_lock_task_context(task, ctxn, &flags); |
c93f7669 | 4289 | if (ctx) { |
211de6eb | 4290 | clone_ctx = unclone_ctx(ctx); |
fe4b04fa | 4291 | ++ctx->pin_count; |
4af57ef2 YZ |
4292 | |
4293 | if (task_ctx_data && !ctx->task_ctx_data) { | |
4294 | ctx->task_ctx_data = task_ctx_data; | |
4295 | task_ctx_data = NULL; | |
4296 | } | |
e625cce1 | 4297 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
211de6eb PZ |
4298 | |
4299 | if (clone_ctx) | |
4300 | put_ctx(clone_ctx); | |
9137fb28 | 4301 | } else { |
eb184479 | 4302 | ctx = alloc_perf_context(pmu, task); |
c93f7669 PM |
4303 | err = -ENOMEM; |
4304 | if (!ctx) | |
4305 | goto errout; | |
eb184479 | 4306 | |
4af57ef2 YZ |
4307 | if (task_ctx_data) { |
4308 | ctx->task_ctx_data = task_ctx_data; | |
4309 | task_ctx_data = NULL; | |
4310 | } | |
4311 | ||
dbe08d82 ON |
4312 | err = 0; |
4313 | mutex_lock(&task->perf_event_mutex); | |
4314 | /* | |
4315 | * If it has already passed perf_event_exit_task(). | |
4316 | * we must see PF_EXITING, it takes this mutex too. | |
4317 | */ | |
4318 | if (task->flags & PF_EXITING) | |
4319 | err = -ESRCH; | |
4320 | else if (task->perf_event_ctxp[ctxn]) | |
4321 | err = -EAGAIN; | |
fe4b04fa | 4322 | else { |
9137fb28 | 4323 | get_ctx(ctx); |
fe4b04fa | 4324 | ++ctx->pin_count; |
dbe08d82 | 4325 | rcu_assign_pointer(task->perf_event_ctxp[ctxn], ctx); |
fe4b04fa | 4326 | } |
dbe08d82 ON |
4327 | mutex_unlock(&task->perf_event_mutex); |
4328 | ||
4329 | if (unlikely(err)) { | |
9137fb28 | 4330 | put_ctx(ctx); |
dbe08d82 ON |
4331 | |
4332 | if (err == -EAGAIN) | |
4333 | goto retry; | |
4334 | goto errout; | |
a63eaf34 PM |
4335 | } |
4336 | } | |
4337 | ||
4af57ef2 | 4338 | kfree(task_ctx_data); |
0793a61d | 4339 | return ctx; |
c93f7669 | 4340 | |
9ed6060d | 4341 | errout: |
4af57ef2 | 4342 | kfree(task_ctx_data); |
c93f7669 | 4343 | return ERR_PTR(err); |
0793a61d TG |
4344 | } |
4345 | ||
6fb2915d | 4346 | static void perf_event_free_filter(struct perf_event *event); |
2541517c | 4347 | static void perf_event_free_bpf_prog(struct perf_event *event); |
6fb2915d | 4348 | |
cdd6c482 | 4349 | static void free_event_rcu(struct rcu_head *head) |
592903cd | 4350 | { |
cdd6c482 | 4351 | struct perf_event *event; |
592903cd | 4352 | |
cdd6c482 IM |
4353 | event = container_of(head, struct perf_event, rcu_head); |
4354 | if (event->ns) | |
4355 | put_pid_ns(event->ns); | |
6fb2915d | 4356 | perf_event_free_filter(event); |
cdd6c482 | 4357 | kfree(event); |
592903cd PZ |
4358 | } |
4359 | ||
b69cf536 | 4360 | static void ring_buffer_attach(struct perf_event *event, |
56de4e8f | 4361 | struct perf_buffer *rb); |
925d519a | 4362 | |
f2fb6bef KL |
4363 | static void detach_sb_event(struct perf_event *event) |
4364 | { | |
4365 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
4366 | ||
4367 | raw_spin_lock(&pel->lock); | |
4368 | list_del_rcu(&event->sb_list); | |
4369 | raw_spin_unlock(&pel->lock); | |
4370 | } | |
4371 | ||
a4f144eb | 4372 | static bool is_sb_event(struct perf_event *event) |
f2fb6bef | 4373 | { |
a4f144eb DCC |
4374 | struct perf_event_attr *attr = &event->attr; |
4375 | ||
f2fb6bef | 4376 | if (event->parent) |
a4f144eb | 4377 | return false; |
f2fb6bef KL |
4378 | |
4379 | if (event->attach_state & PERF_ATTACH_TASK) | |
a4f144eb | 4380 | return false; |
f2fb6bef | 4381 | |
a4f144eb DCC |
4382 | if (attr->mmap || attr->mmap_data || attr->mmap2 || |
4383 | attr->comm || attr->comm_exec || | |
76193a94 | 4384 | attr->task || attr->ksymbol || |
21038f2b SL |
4385 | attr->context_switch || |
4386 | attr->bpf_event) | |
a4f144eb DCC |
4387 | return true; |
4388 | return false; | |
4389 | } | |
4390 | ||
4391 | static void unaccount_pmu_sb_event(struct perf_event *event) | |
4392 | { | |
4393 | if (is_sb_event(event)) | |
4394 | detach_sb_event(event); | |
f2fb6bef KL |
4395 | } |
4396 | ||
4beb31f3 | 4397 | static void unaccount_event_cpu(struct perf_event *event, int cpu) |
f1600952 | 4398 | { |
4beb31f3 FW |
4399 | if (event->parent) |
4400 | return; | |
4401 | ||
4beb31f3 FW |
4402 | if (is_cgroup_event(event)) |
4403 | atomic_dec(&per_cpu(perf_cgroup_events, cpu)); | |
4404 | } | |
925d519a | 4405 | |
555e0c1e FW |
4406 | #ifdef CONFIG_NO_HZ_FULL |
4407 | static DEFINE_SPINLOCK(nr_freq_lock); | |
4408 | #endif | |
4409 | ||
4410 | static void unaccount_freq_event_nohz(void) | |
4411 | { | |
4412 | #ifdef CONFIG_NO_HZ_FULL | |
4413 | spin_lock(&nr_freq_lock); | |
4414 | if (atomic_dec_and_test(&nr_freq_events)) | |
4415 | tick_nohz_dep_clear(TICK_DEP_BIT_PERF_EVENTS); | |
4416 | spin_unlock(&nr_freq_lock); | |
4417 | #endif | |
4418 | } | |
4419 | ||
4420 | static void unaccount_freq_event(void) | |
4421 | { | |
4422 | if (tick_nohz_full_enabled()) | |
4423 | unaccount_freq_event_nohz(); | |
4424 | else | |
4425 | atomic_dec(&nr_freq_events); | |
4426 | } | |
4427 | ||
4beb31f3 FW |
4428 | static void unaccount_event(struct perf_event *event) |
4429 | { | |
25432ae9 PZ |
4430 | bool dec = false; |
4431 | ||
4beb31f3 FW |
4432 | if (event->parent) |
4433 | return; | |
4434 | ||
4435 | if (event->attach_state & PERF_ATTACH_TASK) | |
25432ae9 | 4436 | dec = true; |
4beb31f3 FW |
4437 | if (event->attr.mmap || event->attr.mmap_data) |
4438 | atomic_dec(&nr_mmap_events); | |
4439 | if (event->attr.comm) | |
4440 | atomic_dec(&nr_comm_events); | |
e4222673 HB |
4441 | if (event->attr.namespaces) |
4442 | atomic_dec(&nr_namespaces_events); | |
4beb31f3 FW |
4443 | if (event->attr.task) |
4444 | atomic_dec(&nr_task_events); | |
948b26b6 | 4445 | if (event->attr.freq) |
555e0c1e | 4446 | unaccount_freq_event(); |
45ac1403 | 4447 | if (event->attr.context_switch) { |
25432ae9 | 4448 | dec = true; |
45ac1403 AH |
4449 | atomic_dec(&nr_switch_events); |
4450 | } | |
4beb31f3 | 4451 | if (is_cgroup_event(event)) |
25432ae9 | 4452 | dec = true; |
4beb31f3 | 4453 | if (has_branch_stack(event)) |
25432ae9 | 4454 | dec = true; |
76193a94 SL |
4455 | if (event->attr.ksymbol) |
4456 | atomic_dec(&nr_ksymbol_events); | |
6ee52e2a SL |
4457 | if (event->attr.bpf_event) |
4458 | atomic_dec(&nr_bpf_events); | |
25432ae9 | 4459 | |
9107c89e PZ |
4460 | if (dec) { |
4461 | if (!atomic_add_unless(&perf_sched_count, -1, 1)) | |
4462 | schedule_delayed_work(&perf_sched_work, HZ); | |
4463 | } | |
4beb31f3 FW |
4464 | |
4465 | unaccount_event_cpu(event, event->cpu); | |
f2fb6bef KL |
4466 | |
4467 | unaccount_pmu_sb_event(event); | |
4beb31f3 | 4468 | } |
925d519a | 4469 | |
9107c89e PZ |
4470 | static void perf_sched_delayed(struct work_struct *work) |
4471 | { | |
4472 | mutex_lock(&perf_sched_mutex); | |
4473 | if (atomic_dec_and_test(&perf_sched_count)) | |
4474 | static_branch_disable(&perf_sched_events); | |
4475 | mutex_unlock(&perf_sched_mutex); | |
4476 | } | |
4477 | ||
bed5b25a AS |
4478 | /* |
4479 | * The following implement mutual exclusion of events on "exclusive" pmus | |
4480 | * (PERF_PMU_CAP_EXCLUSIVE). Such pmus can only have one event scheduled | |
4481 | * at a time, so we disallow creating events that might conflict, namely: | |
4482 | * | |
4483 | * 1) cpu-wide events in the presence of per-task events, | |
4484 | * 2) per-task events in the presence of cpu-wide events, | |
4485 | * 3) two matching events on the same context. | |
4486 | * | |
4487 | * The former two cases are handled in the allocation path (perf_event_alloc(), | |
a0733e69 | 4488 | * _free_event()), the latter -- before the first perf_install_in_context(). |
bed5b25a AS |
4489 | */ |
4490 | static int exclusive_event_init(struct perf_event *event) | |
4491 | { | |
4492 | struct pmu *pmu = event->pmu; | |
4493 | ||
8a58ddae | 4494 | if (!is_exclusive_pmu(pmu)) |
bed5b25a AS |
4495 | return 0; |
4496 | ||
4497 | /* | |
4498 | * Prevent co-existence of per-task and cpu-wide events on the | |
4499 | * same exclusive pmu. | |
4500 | * | |
4501 | * Negative pmu::exclusive_cnt means there are cpu-wide | |
4502 | * events on this "exclusive" pmu, positive means there are | |
4503 | * per-task events. | |
4504 | * | |
4505 | * Since this is called in perf_event_alloc() path, event::ctx | |
4506 | * doesn't exist yet; it is, however, safe to use PERF_ATTACH_TASK | |
4507 | * to mean "per-task event", because unlike other attach states it | |
4508 | * never gets cleared. | |
4509 | */ | |
4510 | if (event->attach_state & PERF_ATTACH_TASK) { | |
4511 | if (!atomic_inc_unless_negative(&pmu->exclusive_cnt)) | |
4512 | return -EBUSY; | |
4513 | } else { | |
4514 | if (!atomic_dec_unless_positive(&pmu->exclusive_cnt)) | |
4515 | return -EBUSY; | |
4516 | } | |
4517 | ||
4518 | return 0; | |
4519 | } | |
4520 | ||
4521 | static void exclusive_event_destroy(struct perf_event *event) | |
4522 | { | |
4523 | struct pmu *pmu = event->pmu; | |
4524 | ||
8a58ddae | 4525 | if (!is_exclusive_pmu(pmu)) |
bed5b25a AS |
4526 | return; |
4527 | ||
4528 | /* see comment in exclusive_event_init() */ | |
4529 | if (event->attach_state & PERF_ATTACH_TASK) | |
4530 | atomic_dec(&pmu->exclusive_cnt); | |
4531 | else | |
4532 | atomic_inc(&pmu->exclusive_cnt); | |
4533 | } | |
4534 | ||
4535 | static bool exclusive_event_match(struct perf_event *e1, struct perf_event *e2) | |
4536 | { | |
3bf6215a | 4537 | if ((e1->pmu == e2->pmu) && |
bed5b25a AS |
4538 | (e1->cpu == e2->cpu || |
4539 | e1->cpu == -1 || | |
4540 | e2->cpu == -1)) | |
4541 | return true; | |
4542 | return false; | |
4543 | } | |
4544 | ||
bed5b25a AS |
4545 | static bool exclusive_event_installable(struct perf_event *event, |
4546 | struct perf_event_context *ctx) | |
4547 | { | |
4548 | struct perf_event *iter_event; | |
4549 | struct pmu *pmu = event->pmu; | |
4550 | ||
8a58ddae AS |
4551 | lockdep_assert_held(&ctx->mutex); |
4552 | ||
4553 | if (!is_exclusive_pmu(pmu)) | |
bed5b25a AS |
4554 | return true; |
4555 | ||
4556 | list_for_each_entry(iter_event, &ctx->event_list, event_entry) { | |
4557 | if (exclusive_event_match(iter_event, event)) | |
4558 | return false; | |
4559 | } | |
4560 | ||
4561 | return true; | |
4562 | } | |
4563 | ||
375637bc AS |
4564 | static void perf_addr_filters_splice(struct perf_event *event, |
4565 | struct list_head *head); | |
4566 | ||
683ede43 | 4567 | static void _free_event(struct perf_event *event) |
f1600952 | 4568 | { |
e360adbe | 4569 | irq_work_sync(&event->pending); |
925d519a | 4570 | |
4beb31f3 | 4571 | unaccount_event(event); |
9ee318a7 | 4572 | |
da97e184 JFG |
4573 | security_perf_event_free(event); |
4574 | ||
76369139 | 4575 | if (event->rb) { |
9bb5d40c PZ |
4576 | /* |
4577 | * Can happen when we close an event with re-directed output. | |
4578 | * | |
4579 | * Since we have a 0 refcount, perf_mmap_close() will skip | |
4580 | * over us; possibly making our ring_buffer_put() the last. | |
4581 | */ | |
4582 | mutex_lock(&event->mmap_mutex); | |
b69cf536 | 4583 | ring_buffer_attach(event, NULL); |
9bb5d40c | 4584 | mutex_unlock(&event->mmap_mutex); |
a4be7c27 PZ |
4585 | } |
4586 | ||
e5d1367f SE |
4587 | if (is_cgroup_event(event)) |
4588 | perf_detach_cgroup(event); | |
4589 | ||
a0733e69 PZ |
4590 | if (!event->parent) { |
4591 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) | |
4592 | put_callchain_buffers(); | |
4593 | } | |
4594 | ||
4595 | perf_event_free_bpf_prog(event); | |
375637bc | 4596 | perf_addr_filters_splice(event, NULL); |
c60f83b8 | 4597 | kfree(event->addr_filter_ranges); |
a0733e69 PZ |
4598 | |
4599 | if (event->destroy) | |
4600 | event->destroy(event); | |
4601 | ||
1cf8dfe8 PZ |
4602 | /* |
4603 | * Must be after ->destroy(), due to uprobe_perf_close() using | |
4604 | * hw.target. | |
4605 | */ | |
621b6d2e PB |
4606 | if (event->hw.target) |
4607 | put_task_struct(event->hw.target); | |
4608 | ||
1cf8dfe8 PZ |
4609 | /* |
4610 | * perf_event_free_task() relies on put_ctx() being 'last', in particular | |
4611 | * all task references must be cleaned up. | |
4612 | */ | |
4613 | if (event->ctx) | |
4614 | put_ctx(event->ctx); | |
4615 | ||
62a92c8f AS |
4616 | exclusive_event_destroy(event); |
4617 | module_put(event->pmu->module); | |
a0733e69 PZ |
4618 | |
4619 | call_rcu(&event->rcu_head, free_event_rcu); | |
f1600952 PZ |
4620 | } |
4621 | ||
683ede43 PZ |
4622 | /* |
4623 | * Used to free events which have a known refcount of 1, such as in error paths | |
4624 | * where the event isn't exposed yet and inherited events. | |
4625 | */ | |
4626 | static void free_event(struct perf_event *event) | |
0793a61d | 4627 | { |
683ede43 PZ |
4628 | if (WARN(atomic_long_cmpxchg(&event->refcount, 1, 0) != 1, |
4629 | "unexpected event refcount: %ld; ptr=%p\n", | |
4630 | atomic_long_read(&event->refcount), event)) { | |
4631 | /* leak to avoid use-after-free */ | |
4632 | return; | |
4633 | } | |
0793a61d | 4634 | |
683ede43 | 4635 | _free_event(event); |
0793a61d TG |
4636 | } |
4637 | ||
a66a3052 | 4638 | /* |
f8697762 | 4639 | * Remove user event from the owner task. |
a66a3052 | 4640 | */ |
f8697762 | 4641 | static void perf_remove_from_owner(struct perf_event *event) |
fb0459d7 | 4642 | { |
8882135b | 4643 | struct task_struct *owner; |
fb0459d7 | 4644 | |
8882135b | 4645 | rcu_read_lock(); |
8882135b | 4646 | /* |
f47c02c0 PZ |
4647 | * Matches the smp_store_release() in perf_event_exit_task(). If we |
4648 | * observe !owner it means the list deletion is complete and we can | |
4649 | * indeed free this event, otherwise we need to serialize on | |
8882135b PZ |
4650 | * owner->perf_event_mutex. |
4651 | */ | |
506458ef | 4652 | owner = READ_ONCE(event->owner); |
8882135b PZ |
4653 | if (owner) { |
4654 | /* | |
4655 | * Since delayed_put_task_struct() also drops the last | |
4656 | * task reference we can safely take a new reference | |
4657 | * while holding the rcu_read_lock(). | |
4658 | */ | |
4659 | get_task_struct(owner); | |
4660 | } | |
4661 | rcu_read_unlock(); | |
4662 | ||
4663 | if (owner) { | |
f63a8daa PZ |
4664 | /* |
4665 | * If we're here through perf_event_exit_task() we're already | |
4666 | * holding ctx->mutex which would be an inversion wrt. the | |
4667 | * normal lock order. | |
4668 | * | |
4669 | * However we can safely take this lock because its the child | |
4670 | * ctx->mutex. | |
4671 | */ | |
4672 | mutex_lock_nested(&owner->perf_event_mutex, SINGLE_DEPTH_NESTING); | |
4673 | ||
8882135b PZ |
4674 | /* |
4675 | * We have to re-check the event->owner field, if it is cleared | |
4676 | * we raced with perf_event_exit_task(), acquiring the mutex | |
4677 | * ensured they're done, and we can proceed with freeing the | |
4678 | * event. | |
4679 | */ | |
f47c02c0 | 4680 | if (event->owner) { |
8882135b | 4681 | list_del_init(&event->owner_entry); |
f47c02c0 PZ |
4682 | smp_store_release(&event->owner, NULL); |
4683 | } | |
8882135b PZ |
4684 | mutex_unlock(&owner->perf_event_mutex); |
4685 | put_task_struct(owner); | |
4686 | } | |
f8697762 JO |
4687 | } |
4688 | ||
f8697762 JO |
4689 | static void put_event(struct perf_event *event) |
4690 | { | |
f8697762 JO |
4691 | if (!atomic_long_dec_and_test(&event->refcount)) |
4692 | return; | |
4693 | ||
c6e5b732 PZ |
4694 | _free_event(event); |
4695 | } | |
4696 | ||
4697 | /* | |
4698 | * Kill an event dead; while event:refcount will preserve the event | |
4699 | * object, it will not preserve its functionality. Once the last 'user' | |
4700 | * gives up the object, we'll destroy the thing. | |
4701 | */ | |
4702 | int perf_event_release_kernel(struct perf_event *event) | |
4703 | { | |
a4f4bb6d | 4704 | struct perf_event_context *ctx = event->ctx; |
c6e5b732 | 4705 | struct perf_event *child, *tmp; |
82d94856 | 4706 | LIST_HEAD(free_list); |
c6e5b732 | 4707 | |
a4f4bb6d PZ |
4708 | /* |
4709 | * If we got here through err_file: fput(event_file); we will not have | |
4710 | * attached to a context yet. | |
4711 | */ | |
4712 | if (!ctx) { | |
4713 | WARN_ON_ONCE(event->attach_state & | |
4714 | (PERF_ATTACH_CONTEXT|PERF_ATTACH_GROUP)); | |
4715 | goto no_ctx; | |
4716 | } | |
4717 | ||
f8697762 JO |
4718 | if (!is_kernel_event(event)) |
4719 | perf_remove_from_owner(event); | |
8882135b | 4720 | |
5fa7c8ec | 4721 | ctx = perf_event_ctx_lock(event); |
a83fe28e | 4722 | WARN_ON_ONCE(ctx->parent_ctx); |
a69b0ca4 | 4723 | perf_remove_from_context(event, DETACH_GROUP); |
683ede43 | 4724 | |
a69b0ca4 | 4725 | raw_spin_lock_irq(&ctx->lock); |
683ede43 | 4726 | /* |
d8a8cfc7 | 4727 | * Mark this event as STATE_DEAD, there is no external reference to it |
a69b0ca4 | 4728 | * anymore. |
683ede43 | 4729 | * |
a69b0ca4 PZ |
4730 | * Anybody acquiring event->child_mutex after the below loop _must_ |
4731 | * also see this, most importantly inherit_event() which will avoid | |
4732 | * placing more children on the list. | |
683ede43 | 4733 | * |
c6e5b732 PZ |
4734 | * Thus this guarantees that we will in fact observe and kill _ALL_ |
4735 | * child events. | |
683ede43 | 4736 | */ |
a69b0ca4 PZ |
4737 | event->state = PERF_EVENT_STATE_DEAD; |
4738 | raw_spin_unlock_irq(&ctx->lock); | |
4739 | ||
4740 | perf_event_ctx_unlock(event, ctx); | |
683ede43 | 4741 | |
c6e5b732 PZ |
4742 | again: |
4743 | mutex_lock(&event->child_mutex); | |
4744 | list_for_each_entry(child, &event->child_list, child_list) { | |
a6fa941d | 4745 | |
c6e5b732 PZ |
4746 | /* |
4747 | * Cannot change, child events are not migrated, see the | |
4748 | * comment with perf_event_ctx_lock_nested(). | |
4749 | */ | |
506458ef | 4750 | ctx = READ_ONCE(child->ctx); |
c6e5b732 PZ |
4751 | /* |
4752 | * Since child_mutex nests inside ctx::mutex, we must jump | |
4753 | * through hoops. We start by grabbing a reference on the ctx. | |
4754 | * | |
4755 | * Since the event cannot get freed while we hold the | |
4756 | * child_mutex, the context must also exist and have a !0 | |
4757 | * reference count. | |
4758 | */ | |
4759 | get_ctx(ctx); | |
4760 | ||
4761 | /* | |
4762 | * Now that we have a ctx ref, we can drop child_mutex, and | |
4763 | * acquire ctx::mutex without fear of it going away. Then we | |
4764 | * can re-acquire child_mutex. | |
4765 | */ | |
4766 | mutex_unlock(&event->child_mutex); | |
4767 | mutex_lock(&ctx->mutex); | |
4768 | mutex_lock(&event->child_mutex); | |
4769 | ||
4770 | /* | |
4771 | * Now that we hold ctx::mutex and child_mutex, revalidate our | |
4772 | * state, if child is still the first entry, it didn't get freed | |
4773 | * and we can continue doing so. | |
4774 | */ | |
4775 | tmp = list_first_entry_or_null(&event->child_list, | |
4776 | struct perf_event, child_list); | |
4777 | if (tmp == child) { | |
4778 | perf_remove_from_context(child, DETACH_GROUP); | |
82d94856 | 4779 | list_move(&child->child_list, &free_list); |
c6e5b732 PZ |
4780 | /* |
4781 | * This matches the refcount bump in inherit_event(); | |
4782 | * this can't be the last reference. | |
4783 | */ | |
4784 | put_event(event); | |
4785 | } | |
4786 | ||
4787 | mutex_unlock(&event->child_mutex); | |
4788 | mutex_unlock(&ctx->mutex); | |
4789 | put_ctx(ctx); | |
4790 | goto again; | |
4791 | } | |
4792 | mutex_unlock(&event->child_mutex); | |
4793 | ||
82d94856 | 4794 | list_for_each_entry_safe(child, tmp, &free_list, child_list) { |
1cf8dfe8 PZ |
4795 | void *var = &child->ctx->refcount; |
4796 | ||
82d94856 PZ |
4797 | list_del(&child->child_list); |
4798 | free_event(child); | |
1cf8dfe8 PZ |
4799 | |
4800 | /* | |
4801 | * Wake any perf_event_free_task() waiting for this event to be | |
4802 | * freed. | |
4803 | */ | |
4804 | smp_mb(); /* pairs with wait_var_event() */ | |
4805 | wake_up_var(var); | |
82d94856 PZ |
4806 | } |
4807 | ||
a4f4bb6d PZ |
4808 | no_ctx: |
4809 | put_event(event); /* Must be the 'last' reference */ | |
683ede43 PZ |
4810 | return 0; |
4811 | } | |
4812 | EXPORT_SYMBOL_GPL(perf_event_release_kernel); | |
4813 | ||
8b10c5e2 PZ |
4814 | /* |
4815 | * Called when the last reference to the file is gone. | |
4816 | */ | |
a6fa941d AV |
4817 | static int perf_release(struct inode *inode, struct file *file) |
4818 | { | |
c6e5b732 | 4819 | perf_event_release_kernel(file->private_data); |
a6fa941d | 4820 | return 0; |
fb0459d7 | 4821 | } |
fb0459d7 | 4822 | |
ca0dd44c | 4823 | static u64 __perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) |
e53c0994 | 4824 | { |
cdd6c482 | 4825 | struct perf_event *child; |
e53c0994 PZ |
4826 | u64 total = 0; |
4827 | ||
59ed446f PZ |
4828 | *enabled = 0; |
4829 | *running = 0; | |
4830 | ||
6f10581a | 4831 | mutex_lock(&event->child_mutex); |
01add3ea | 4832 | |
7d88962e | 4833 | (void)perf_event_read(event, false); |
01add3ea SB |
4834 | total += perf_event_count(event); |
4835 | ||
59ed446f PZ |
4836 | *enabled += event->total_time_enabled + |
4837 | atomic64_read(&event->child_total_time_enabled); | |
4838 | *running += event->total_time_running + | |
4839 | atomic64_read(&event->child_total_time_running); | |
4840 | ||
4841 | list_for_each_entry(child, &event->child_list, child_list) { | |
7d88962e | 4842 | (void)perf_event_read(child, false); |
01add3ea | 4843 | total += perf_event_count(child); |
59ed446f PZ |
4844 | *enabled += child->total_time_enabled; |
4845 | *running += child->total_time_running; | |
4846 | } | |
6f10581a | 4847 | mutex_unlock(&event->child_mutex); |
e53c0994 PZ |
4848 | |
4849 | return total; | |
4850 | } | |
ca0dd44c PZ |
4851 | |
4852 | u64 perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) | |
4853 | { | |
4854 | struct perf_event_context *ctx; | |
4855 | u64 count; | |
4856 | ||
4857 | ctx = perf_event_ctx_lock(event); | |
4858 | count = __perf_event_read_value(event, enabled, running); | |
4859 | perf_event_ctx_unlock(event, ctx); | |
4860 | ||
4861 | return count; | |
4862 | } | |
fb0459d7 | 4863 | EXPORT_SYMBOL_GPL(perf_event_read_value); |
e53c0994 | 4864 | |
7d88962e | 4865 | static int __perf_read_group_add(struct perf_event *leader, |
fa8c2693 | 4866 | u64 read_format, u64 *values) |
3dab77fb | 4867 | { |
2aeb1883 | 4868 | struct perf_event_context *ctx = leader->ctx; |
fa8c2693 | 4869 | struct perf_event *sub; |
2aeb1883 | 4870 | unsigned long flags; |
fa8c2693 | 4871 | int n = 1; /* skip @nr */ |
7d88962e | 4872 | int ret; |
f63a8daa | 4873 | |
7d88962e SB |
4874 | ret = perf_event_read(leader, true); |
4875 | if (ret) | |
4876 | return ret; | |
abf4868b | 4877 | |
a9cd8194 PZ |
4878 | raw_spin_lock_irqsave(&ctx->lock, flags); |
4879 | ||
fa8c2693 PZ |
4880 | /* |
4881 | * Since we co-schedule groups, {enabled,running} times of siblings | |
4882 | * will be identical to those of the leader, so we only publish one | |
4883 | * set. | |
4884 | */ | |
4885 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { | |
4886 | values[n++] += leader->total_time_enabled + | |
4887 | atomic64_read(&leader->child_total_time_enabled); | |
4888 | } | |
3dab77fb | 4889 | |
fa8c2693 PZ |
4890 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { |
4891 | values[n++] += leader->total_time_running + | |
4892 | atomic64_read(&leader->child_total_time_running); | |
4893 | } | |
4894 | ||
4895 | /* | |
4896 | * Write {count,id} tuples for every sibling. | |
4897 | */ | |
4898 | values[n++] += perf_event_count(leader); | |
abf4868b PZ |
4899 | if (read_format & PERF_FORMAT_ID) |
4900 | values[n++] = primary_event_id(leader); | |
3dab77fb | 4901 | |
edb39592 | 4902 | for_each_sibling_event(sub, leader) { |
fa8c2693 PZ |
4903 | values[n++] += perf_event_count(sub); |
4904 | if (read_format & PERF_FORMAT_ID) | |
4905 | values[n++] = primary_event_id(sub); | |
4906 | } | |
7d88962e | 4907 | |
2aeb1883 | 4908 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
7d88962e | 4909 | return 0; |
fa8c2693 | 4910 | } |
3dab77fb | 4911 | |
fa8c2693 PZ |
4912 | static int perf_read_group(struct perf_event *event, |
4913 | u64 read_format, char __user *buf) | |
4914 | { | |
4915 | struct perf_event *leader = event->group_leader, *child; | |
4916 | struct perf_event_context *ctx = leader->ctx; | |
7d88962e | 4917 | int ret; |
fa8c2693 | 4918 | u64 *values; |
3dab77fb | 4919 | |
fa8c2693 | 4920 | lockdep_assert_held(&ctx->mutex); |
3dab77fb | 4921 | |
fa8c2693 PZ |
4922 | values = kzalloc(event->read_size, GFP_KERNEL); |
4923 | if (!values) | |
4924 | return -ENOMEM; | |
3dab77fb | 4925 | |
fa8c2693 PZ |
4926 | values[0] = 1 + leader->nr_siblings; |
4927 | ||
4928 | /* | |
4929 | * By locking the child_mutex of the leader we effectively | |
4930 | * lock the child list of all siblings.. XXX explain how. | |
4931 | */ | |
4932 | mutex_lock(&leader->child_mutex); | |
abf4868b | 4933 | |
7d88962e SB |
4934 | ret = __perf_read_group_add(leader, read_format, values); |
4935 | if (ret) | |
4936 | goto unlock; | |
4937 | ||
4938 | list_for_each_entry(child, &leader->child_list, child_list) { | |
4939 | ret = __perf_read_group_add(child, read_format, values); | |
4940 | if (ret) | |
4941 | goto unlock; | |
4942 | } | |
abf4868b | 4943 | |
fa8c2693 | 4944 | mutex_unlock(&leader->child_mutex); |
abf4868b | 4945 | |
7d88962e | 4946 | ret = event->read_size; |
fa8c2693 PZ |
4947 | if (copy_to_user(buf, values, event->read_size)) |
4948 | ret = -EFAULT; | |
7d88962e | 4949 | goto out; |
fa8c2693 | 4950 | |
7d88962e SB |
4951 | unlock: |
4952 | mutex_unlock(&leader->child_mutex); | |
4953 | out: | |
fa8c2693 | 4954 | kfree(values); |
abf4868b | 4955 | return ret; |
3dab77fb PZ |
4956 | } |
4957 | ||
b15f495b | 4958 | static int perf_read_one(struct perf_event *event, |
3dab77fb PZ |
4959 | u64 read_format, char __user *buf) |
4960 | { | |
59ed446f | 4961 | u64 enabled, running; |
3dab77fb PZ |
4962 | u64 values[4]; |
4963 | int n = 0; | |
4964 | ||
ca0dd44c | 4965 | values[n++] = __perf_event_read_value(event, &enabled, &running); |
59ed446f PZ |
4966 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) |
4967 | values[n++] = enabled; | |
4968 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
4969 | values[n++] = running; | |
3dab77fb | 4970 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 4971 | values[n++] = primary_event_id(event); |
3dab77fb PZ |
4972 | |
4973 | if (copy_to_user(buf, values, n * sizeof(u64))) | |
4974 | return -EFAULT; | |
4975 | ||
4976 | return n * sizeof(u64); | |
4977 | } | |
4978 | ||
dc633982 JO |
4979 | static bool is_event_hup(struct perf_event *event) |
4980 | { | |
4981 | bool no_children; | |
4982 | ||
a69b0ca4 | 4983 | if (event->state > PERF_EVENT_STATE_EXIT) |
dc633982 JO |
4984 | return false; |
4985 | ||
4986 | mutex_lock(&event->child_mutex); | |
4987 | no_children = list_empty(&event->child_list); | |
4988 | mutex_unlock(&event->child_mutex); | |
4989 | return no_children; | |
4990 | } | |
4991 | ||
0793a61d | 4992 | /* |
cdd6c482 | 4993 | * Read the performance event - simple non blocking version for now |
0793a61d TG |
4994 | */ |
4995 | static ssize_t | |
b15f495b | 4996 | __perf_read(struct perf_event *event, char __user *buf, size_t count) |
0793a61d | 4997 | { |
cdd6c482 | 4998 | u64 read_format = event->attr.read_format; |
3dab77fb | 4999 | int ret; |
0793a61d | 5000 | |
3b6f9e5c | 5001 | /* |
788faab7 | 5002 | * Return end-of-file for a read on an event that is in |
3b6f9e5c PM |
5003 | * error state (i.e. because it was pinned but it couldn't be |
5004 | * scheduled on to the CPU at some point). | |
5005 | */ | |
cdd6c482 | 5006 | if (event->state == PERF_EVENT_STATE_ERROR) |
3b6f9e5c PM |
5007 | return 0; |
5008 | ||
c320c7b7 | 5009 | if (count < event->read_size) |
3dab77fb PZ |
5010 | return -ENOSPC; |
5011 | ||
cdd6c482 | 5012 | WARN_ON_ONCE(event->ctx->parent_ctx); |
3dab77fb | 5013 | if (read_format & PERF_FORMAT_GROUP) |
b15f495b | 5014 | ret = perf_read_group(event, read_format, buf); |
3dab77fb | 5015 | else |
b15f495b | 5016 | ret = perf_read_one(event, read_format, buf); |
0793a61d | 5017 | |
3dab77fb | 5018 | return ret; |
0793a61d TG |
5019 | } |
5020 | ||
0793a61d TG |
5021 | static ssize_t |
5022 | perf_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) | |
5023 | { | |
cdd6c482 | 5024 | struct perf_event *event = file->private_data; |
f63a8daa PZ |
5025 | struct perf_event_context *ctx; |
5026 | int ret; | |
0793a61d | 5027 | |
da97e184 JFG |
5028 | ret = security_perf_event_read(event); |
5029 | if (ret) | |
5030 | return ret; | |
5031 | ||
f63a8daa | 5032 | ctx = perf_event_ctx_lock(event); |
b15f495b | 5033 | ret = __perf_read(event, buf, count); |
f63a8daa PZ |
5034 | perf_event_ctx_unlock(event, ctx); |
5035 | ||
5036 | return ret; | |
0793a61d TG |
5037 | } |
5038 | ||
9dd95748 | 5039 | static __poll_t perf_poll(struct file *file, poll_table *wait) |
0793a61d | 5040 | { |
cdd6c482 | 5041 | struct perf_event *event = file->private_data; |
56de4e8f | 5042 | struct perf_buffer *rb; |
a9a08845 | 5043 | __poll_t events = EPOLLHUP; |
c7138f37 | 5044 | |
e708d7ad | 5045 | poll_wait(file, &event->waitq, wait); |
179033b3 | 5046 | |
dc633982 | 5047 | if (is_event_hup(event)) |
179033b3 | 5048 | return events; |
c7138f37 | 5049 | |
10c6db11 | 5050 | /* |
9bb5d40c PZ |
5051 | * Pin the event->rb by taking event->mmap_mutex; otherwise |
5052 | * perf_event_set_output() can swizzle our rb and make us miss wakeups. | |
10c6db11 PZ |
5053 | */ |
5054 | mutex_lock(&event->mmap_mutex); | |
9bb5d40c PZ |
5055 | rb = event->rb; |
5056 | if (rb) | |
76369139 | 5057 | events = atomic_xchg(&rb->poll, 0); |
10c6db11 | 5058 | mutex_unlock(&event->mmap_mutex); |
0793a61d TG |
5059 | return events; |
5060 | } | |
5061 | ||
f63a8daa | 5062 | static void _perf_event_reset(struct perf_event *event) |
6de6a7b9 | 5063 | { |
7d88962e | 5064 | (void)perf_event_read(event, false); |
e7850595 | 5065 | local64_set(&event->count, 0); |
cdd6c482 | 5066 | perf_event_update_userpage(event); |
3df5edad PZ |
5067 | } |
5068 | ||
52ba4b0b LX |
5069 | /* Assume it's not an event with inherit set. */ |
5070 | u64 perf_event_pause(struct perf_event *event, bool reset) | |
5071 | { | |
5072 | struct perf_event_context *ctx; | |
5073 | u64 count; | |
5074 | ||
5075 | ctx = perf_event_ctx_lock(event); | |
5076 | WARN_ON_ONCE(event->attr.inherit); | |
5077 | _perf_event_disable(event); | |
5078 | count = local64_read(&event->count); | |
5079 | if (reset) | |
5080 | local64_set(&event->count, 0); | |
5081 | perf_event_ctx_unlock(event, ctx); | |
5082 | ||
5083 | return count; | |
5084 | } | |
5085 | EXPORT_SYMBOL_GPL(perf_event_pause); | |
5086 | ||
c93f7669 | 5087 | /* |
cdd6c482 IM |
5088 | * Holding the top-level event's child_mutex means that any |
5089 | * descendant process that has inherited this event will block | |
8ba289b8 | 5090 | * in perf_event_exit_event() if it goes to exit, thus satisfying the |
cdd6c482 | 5091 | * task existence requirements of perf_event_enable/disable. |
c93f7669 | 5092 | */ |
cdd6c482 IM |
5093 | static void perf_event_for_each_child(struct perf_event *event, |
5094 | void (*func)(struct perf_event *)) | |
3df5edad | 5095 | { |
cdd6c482 | 5096 | struct perf_event *child; |
3df5edad | 5097 | |
cdd6c482 | 5098 | WARN_ON_ONCE(event->ctx->parent_ctx); |
f63a8daa | 5099 | |
cdd6c482 IM |
5100 | mutex_lock(&event->child_mutex); |
5101 | func(event); | |
5102 | list_for_each_entry(child, &event->child_list, child_list) | |
3df5edad | 5103 | func(child); |
cdd6c482 | 5104 | mutex_unlock(&event->child_mutex); |
3df5edad PZ |
5105 | } |
5106 | ||
cdd6c482 IM |
5107 | static void perf_event_for_each(struct perf_event *event, |
5108 | void (*func)(struct perf_event *)) | |
3df5edad | 5109 | { |
cdd6c482 IM |
5110 | struct perf_event_context *ctx = event->ctx; |
5111 | struct perf_event *sibling; | |
3df5edad | 5112 | |
f63a8daa PZ |
5113 | lockdep_assert_held(&ctx->mutex); |
5114 | ||
cdd6c482 | 5115 | event = event->group_leader; |
75f937f2 | 5116 | |
cdd6c482 | 5117 | perf_event_for_each_child(event, func); |
edb39592 | 5118 | for_each_sibling_event(sibling, event) |
724b6daa | 5119 | perf_event_for_each_child(sibling, func); |
6de6a7b9 PZ |
5120 | } |
5121 | ||
fae3fde6 PZ |
5122 | static void __perf_event_period(struct perf_event *event, |
5123 | struct perf_cpu_context *cpuctx, | |
5124 | struct perf_event_context *ctx, | |
5125 | void *info) | |
c7999c6f | 5126 | { |
fae3fde6 | 5127 | u64 value = *((u64 *)info); |
c7999c6f | 5128 | bool active; |
08247e31 | 5129 | |
cdd6c482 | 5130 | if (event->attr.freq) { |
cdd6c482 | 5131 | event->attr.sample_freq = value; |
08247e31 | 5132 | } else { |
cdd6c482 IM |
5133 | event->attr.sample_period = value; |
5134 | event->hw.sample_period = value; | |
08247e31 | 5135 | } |
bad7192b PZ |
5136 | |
5137 | active = (event->state == PERF_EVENT_STATE_ACTIVE); | |
5138 | if (active) { | |
5139 | perf_pmu_disable(ctx->pmu); | |
1e02cd40 PZ |
5140 | /* |
5141 | * We could be throttled; unthrottle now to avoid the tick | |
5142 | * trying to unthrottle while we already re-started the event. | |
5143 | */ | |
5144 | if (event->hw.interrupts == MAX_INTERRUPTS) { | |
5145 | event->hw.interrupts = 0; | |
5146 | perf_log_throttle(event, 1); | |
5147 | } | |
bad7192b PZ |
5148 | event->pmu->stop(event, PERF_EF_UPDATE); |
5149 | } | |
5150 | ||
5151 | local64_set(&event->hw.period_left, 0); | |
5152 | ||
5153 | if (active) { | |
5154 | event->pmu->start(event, PERF_EF_RELOAD); | |
5155 | perf_pmu_enable(ctx->pmu); | |
5156 | } | |
c7999c6f PZ |
5157 | } |
5158 | ||
81ec3f3c JO |
5159 | static int perf_event_check_period(struct perf_event *event, u64 value) |
5160 | { | |
5161 | return event->pmu->check_period(event, value); | |
5162 | } | |
5163 | ||
3ca270fc | 5164 | static int _perf_event_period(struct perf_event *event, u64 value) |
c7999c6f | 5165 | { |
c7999c6f PZ |
5166 | if (!is_sampling_event(event)) |
5167 | return -EINVAL; | |
5168 | ||
c7999c6f PZ |
5169 | if (!value) |
5170 | return -EINVAL; | |
5171 | ||
5172 | if (event->attr.freq && value > sysctl_perf_event_sample_rate) | |
5173 | return -EINVAL; | |
5174 | ||
81ec3f3c JO |
5175 | if (perf_event_check_period(event, value)) |
5176 | return -EINVAL; | |
5177 | ||
913a90bc RB |
5178 | if (!event->attr.freq && (value & (1ULL << 63))) |
5179 | return -EINVAL; | |
5180 | ||
fae3fde6 | 5181 | event_function_call(event, __perf_event_period, &value); |
08247e31 | 5182 | |
c7999c6f | 5183 | return 0; |
08247e31 PZ |
5184 | } |
5185 | ||
3ca270fc LX |
5186 | int perf_event_period(struct perf_event *event, u64 value) |
5187 | { | |
5188 | struct perf_event_context *ctx; | |
5189 | int ret; | |
5190 | ||
5191 | ctx = perf_event_ctx_lock(event); | |
5192 | ret = _perf_event_period(event, value); | |
5193 | perf_event_ctx_unlock(event, ctx); | |
5194 | ||
5195 | return ret; | |
5196 | } | |
5197 | EXPORT_SYMBOL_GPL(perf_event_period); | |
5198 | ||
ac9721f3 PZ |
5199 | static const struct file_operations perf_fops; |
5200 | ||
2903ff01 | 5201 | static inline int perf_fget_light(int fd, struct fd *p) |
ac9721f3 | 5202 | { |
2903ff01 AV |
5203 | struct fd f = fdget(fd); |
5204 | if (!f.file) | |
5205 | return -EBADF; | |
ac9721f3 | 5206 | |
2903ff01 AV |
5207 | if (f.file->f_op != &perf_fops) { |
5208 | fdput(f); | |
5209 | return -EBADF; | |
ac9721f3 | 5210 | } |
2903ff01 AV |
5211 | *p = f; |
5212 | return 0; | |
ac9721f3 PZ |
5213 | } |
5214 | ||
5215 | static int perf_event_set_output(struct perf_event *event, | |
5216 | struct perf_event *output_event); | |
6fb2915d | 5217 | static int perf_event_set_filter(struct perf_event *event, void __user *arg); |
2541517c | 5218 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd); |
32ff77e8 MC |
5219 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
5220 | struct perf_event_attr *attr); | |
a4be7c27 | 5221 | |
f63a8daa | 5222 | static long _perf_ioctl(struct perf_event *event, unsigned int cmd, unsigned long arg) |
d859e29f | 5223 | { |
cdd6c482 | 5224 | void (*func)(struct perf_event *); |
3df5edad | 5225 | u32 flags = arg; |
d859e29f PM |
5226 | |
5227 | switch (cmd) { | |
cdd6c482 | 5228 | case PERF_EVENT_IOC_ENABLE: |
f63a8daa | 5229 | func = _perf_event_enable; |
d859e29f | 5230 | break; |
cdd6c482 | 5231 | case PERF_EVENT_IOC_DISABLE: |
f63a8daa | 5232 | func = _perf_event_disable; |
79f14641 | 5233 | break; |
cdd6c482 | 5234 | case PERF_EVENT_IOC_RESET: |
f63a8daa | 5235 | func = _perf_event_reset; |
6de6a7b9 | 5236 | break; |
3df5edad | 5237 | |
cdd6c482 | 5238 | case PERF_EVENT_IOC_REFRESH: |
f63a8daa | 5239 | return _perf_event_refresh(event, arg); |
08247e31 | 5240 | |
cdd6c482 | 5241 | case PERF_EVENT_IOC_PERIOD: |
3ca270fc LX |
5242 | { |
5243 | u64 value; | |
08247e31 | 5244 | |
3ca270fc LX |
5245 | if (copy_from_user(&value, (u64 __user *)arg, sizeof(value))) |
5246 | return -EFAULT; | |
08247e31 | 5247 | |
3ca270fc LX |
5248 | return _perf_event_period(event, value); |
5249 | } | |
cf4957f1 JO |
5250 | case PERF_EVENT_IOC_ID: |
5251 | { | |
5252 | u64 id = primary_event_id(event); | |
5253 | ||
5254 | if (copy_to_user((void __user *)arg, &id, sizeof(id))) | |
5255 | return -EFAULT; | |
5256 | return 0; | |
5257 | } | |
5258 | ||
cdd6c482 | 5259 | case PERF_EVENT_IOC_SET_OUTPUT: |
ac9721f3 | 5260 | { |
ac9721f3 | 5261 | int ret; |
ac9721f3 | 5262 | if (arg != -1) { |
2903ff01 AV |
5263 | struct perf_event *output_event; |
5264 | struct fd output; | |
5265 | ret = perf_fget_light(arg, &output); | |
5266 | if (ret) | |
5267 | return ret; | |
5268 | output_event = output.file->private_data; | |
5269 | ret = perf_event_set_output(event, output_event); | |
5270 | fdput(output); | |
5271 | } else { | |
5272 | ret = perf_event_set_output(event, NULL); | |
ac9721f3 | 5273 | } |
ac9721f3 PZ |
5274 | return ret; |
5275 | } | |
a4be7c27 | 5276 | |
6fb2915d LZ |
5277 | case PERF_EVENT_IOC_SET_FILTER: |
5278 | return perf_event_set_filter(event, (void __user *)arg); | |
5279 | ||
2541517c AS |
5280 | case PERF_EVENT_IOC_SET_BPF: |
5281 | return perf_event_set_bpf_prog(event, arg); | |
5282 | ||
86e7972f | 5283 | case PERF_EVENT_IOC_PAUSE_OUTPUT: { |
56de4e8f | 5284 | struct perf_buffer *rb; |
86e7972f WN |
5285 | |
5286 | rcu_read_lock(); | |
5287 | rb = rcu_dereference(event->rb); | |
5288 | if (!rb || !rb->nr_pages) { | |
5289 | rcu_read_unlock(); | |
5290 | return -EINVAL; | |
5291 | } | |
5292 | rb_toggle_paused(rb, !!arg); | |
5293 | rcu_read_unlock(); | |
5294 | return 0; | |
5295 | } | |
f371b304 YS |
5296 | |
5297 | case PERF_EVENT_IOC_QUERY_BPF: | |
f4e2298e | 5298 | return perf_event_query_prog_array(event, (void __user *)arg); |
32ff77e8 MC |
5299 | |
5300 | case PERF_EVENT_IOC_MODIFY_ATTRIBUTES: { | |
5301 | struct perf_event_attr new_attr; | |
5302 | int err = perf_copy_attr((struct perf_event_attr __user *)arg, | |
5303 | &new_attr); | |
5304 | ||
5305 | if (err) | |
5306 | return err; | |
5307 | ||
5308 | return perf_event_modify_attr(event, &new_attr); | |
5309 | } | |
d859e29f | 5310 | default: |
3df5edad | 5311 | return -ENOTTY; |
d859e29f | 5312 | } |
3df5edad PZ |
5313 | |
5314 | if (flags & PERF_IOC_FLAG_GROUP) | |
cdd6c482 | 5315 | perf_event_for_each(event, func); |
3df5edad | 5316 | else |
cdd6c482 | 5317 | perf_event_for_each_child(event, func); |
3df5edad PZ |
5318 | |
5319 | return 0; | |
d859e29f PM |
5320 | } |
5321 | ||
f63a8daa PZ |
5322 | static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
5323 | { | |
5324 | struct perf_event *event = file->private_data; | |
5325 | struct perf_event_context *ctx; | |
5326 | long ret; | |
5327 | ||
da97e184 JFG |
5328 | /* Treat ioctl like writes as it is likely a mutating operation. */ |
5329 | ret = security_perf_event_write(event); | |
5330 | if (ret) | |
5331 | return ret; | |
5332 | ||
f63a8daa PZ |
5333 | ctx = perf_event_ctx_lock(event); |
5334 | ret = _perf_ioctl(event, cmd, arg); | |
5335 | perf_event_ctx_unlock(event, ctx); | |
5336 | ||
5337 | return ret; | |
5338 | } | |
5339 | ||
b3f20785 PM |
5340 | #ifdef CONFIG_COMPAT |
5341 | static long perf_compat_ioctl(struct file *file, unsigned int cmd, | |
5342 | unsigned long arg) | |
5343 | { | |
5344 | switch (_IOC_NR(cmd)) { | |
5345 | case _IOC_NR(PERF_EVENT_IOC_SET_FILTER): | |
5346 | case _IOC_NR(PERF_EVENT_IOC_ID): | |
82489c5f ES |
5347 | case _IOC_NR(PERF_EVENT_IOC_QUERY_BPF): |
5348 | case _IOC_NR(PERF_EVENT_IOC_MODIFY_ATTRIBUTES): | |
b3f20785 PM |
5349 | /* Fix up pointer size (usually 4 -> 8 in 32-on-64-bit case */ |
5350 | if (_IOC_SIZE(cmd) == sizeof(compat_uptr_t)) { | |
5351 | cmd &= ~IOCSIZE_MASK; | |
5352 | cmd |= sizeof(void *) << IOCSIZE_SHIFT; | |
5353 | } | |
5354 | break; | |
5355 | } | |
5356 | return perf_ioctl(file, cmd, arg); | |
5357 | } | |
5358 | #else | |
5359 | # define perf_compat_ioctl NULL | |
5360 | #endif | |
5361 | ||
cdd6c482 | 5362 | int perf_event_task_enable(void) |
771d7cde | 5363 | { |
f63a8daa | 5364 | struct perf_event_context *ctx; |
cdd6c482 | 5365 | struct perf_event *event; |
771d7cde | 5366 | |
cdd6c482 | 5367 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
5368 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
5369 | ctx = perf_event_ctx_lock(event); | |
5370 | perf_event_for_each_child(event, _perf_event_enable); | |
5371 | perf_event_ctx_unlock(event, ctx); | |
5372 | } | |
cdd6c482 | 5373 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
5374 | |
5375 | return 0; | |
5376 | } | |
5377 | ||
cdd6c482 | 5378 | int perf_event_task_disable(void) |
771d7cde | 5379 | { |
f63a8daa | 5380 | struct perf_event_context *ctx; |
cdd6c482 | 5381 | struct perf_event *event; |
771d7cde | 5382 | |
cdd6c482 | 5383 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
5384 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
5385 | ctx = perf_event_ctx_lock(event); | |
5386 | perf_event_for_each_child(event, _perf_event_disable); | |
5387 | perf_event_ctx_unlock(event, ctx); | |
5388 | } | |
cdd6c482 | 5389 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
5390 | |
5391 | return 0; | |
5392 | } | |
5393 | ||
cdd6c482 | 5394 | static int perf_event_index(struct perf_event *event) |
194002b2 | 5395 | { |
a4eaf7f1 PZ |
5396 | if (event->hw.state & PERF_HES_STOPPED) |
5397 | return 0; | |
5398 | ||
cdd6c482 | 5399 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
194002b2 PZ |
5400 | return 0; |
5401 | ||
35edc2a5 | 5402 | return event->pmu->event_idx(event); |
194002b2 PZ |
5403 | } |
5404 | ||
c4794295 | 5405 | static void calc_timer_values(struct perf_event *event, |
e3f3541c | 5406 | u64 *now, |
7f310a5d EM |
5407 | u64 *enabled, |
5408 | u64 *running) | |
c4794295 | 5409 | { |
e3f3541c | 5410 | u64 ctx_time; |
c4794295 | 5411 | |
e3f3541c PZ |
5412 | *now = perf_clock(); |
5413 | ctx_time = event->shadow_ctx_time + *now; | |
0d3d73aa | 5414 | __perf_update_times(event, ctx_time, enabled, running); |
c4794295 EM |
5415 | } |
5416 | ||
fa731587 PZ |
5417 | static void perf_event_init_userpage(struct perf_event *event) |
5418 | { | |
5419 | struct perf_event_mmap_page *userpg; | |
56de4e8f | 5420 | struct perf_buffer *rb; |
fa731587 PZ |
5421 | |
5422 | rcu_read_lock(); | |
5423 | rb = rcu_dereference(event->rb); | |
5424 | if (!rb) | |
5425 | goto unlock; | |
5426 | ||
5427 | userpg = rb->user_page; | |
5428 | ||
5429 | /* Allow new userspace to detect that bit 0 is deprecated */ | |
5430 | userpg->cap_bit0_is_deprecated = 1; | |
5431 | userpg->size = offsetof(struct perf_event_mmap_page, __reserved); | |
e8c6deac AS |
5432 | userpg->data_offset = PAGE_SIZE; |
5433 | userpg->data_size = perf_data_size(rb); | |
fa731587 PZ |
5434 | |
5435 | unlock: | |
5436 | rcu_read_unlock(); | |
5437 | } | |
5438 | ||
c1317ec2 AL |
5439 | void __weak arch_perf_update_userpage( |
5440 | struct perf_event *event, struct perf_event_mmap_page *userpg, u64 now) | |
e3f3541c PZ |
5441 | { |
5442 | } | |
5443 | ||
38ff667b PZ |
5444 | /* |
5445 | * Callers need to ensure there can be no nesting of this function, otherwise | |
5446 | * the seqlock logic goes bad. We can not serialize this because the arch | |
5447 | * code calls this from NMI context. | |
5448 | */ | |
cdd6c482 | 5449 | void perf_event_update_userpage(struct perf_event *event) |
37d81828 | 5450 | { |
cdd6c482 | 5451 | struct perf_event_mmap_page *userpg; |
56de4e8f | 5452 | struct perf_buffer *rb; |
e3f3541c | 5453 | u64 enabled, running, now; |
38ff667b PZ |
5454 | |
5455 | rcu_read_lock(); | |
5ec4c599 PZ |
5456 | rb = rcu_dereference(event->rb); |
5457 | if (!rb) | |
5458 | goto unlock; | |
5459 | ||
0d641208 EM |
5460 | /* |
5461 | * compute total_time_enabled, total_time_running | |
5462 | * based on snapshot values taken when the event | |
5463 | * was last scheduled in. | |
5464 | * | |
5465 | * we cannot simply called update_context_time() | |
5466 | * because of locking issue as we can be called in | |
5467 | * NMI context | |
5468 | */ | |
e3f3541c | 5469 | calc_timer_values(event, &now, &enabled, &running); |
38ff667b | 5470 | |
76369139 | 5471 | userpg = rb->user_page; |
7b732a75 | 5472 | /* |
9d2dcc8f MF |
5473 | * Disable preemption to guarantee consistent time stamps are stored to |
5474 | * the user page. | |
7b732a75 PZ |
5475 | */ |
5476 | preempt_disable(); | |
37d81828 | 5477 | ++userpg->lock; |
92f22a38 | 5478 | barrier(); |
cdd6c482 | 5479 | userpg->index = perf_event_index(event); |
b5e58793 | 5480 | userpg->offset = perf_event_count(event); |
365a4038 | 5481 | if (userpg->index) |
e7850595 | 5482 | userpg->offset -= local64_read(&event->hw.prev_count); |
7b732a75 | 5483 | |
0d641208 | 5484 | userpg->time_enabled = enabled + |
cdd6c482 | 5485 | atomic64_read(&event->child_total_time_enabled); |
7f8b4e4e | 5486 | |
0d641208 | 5487 | userpg->time_running = running + |
cdd6c482 | 5488 | atomic64_read(&event->child_total_time_running); |
7f8b4e4e | 5489 | |
c1317ec2 | 5490 | arch_perf_update_userpage(event, userpg, now); |
e3f3541c | 5491 | |
92f22a38 | 5492 | barrier(); |
37d81828 | 5493 | ++userpg->lock; |
7b732a75 | 5494 | preempt_enable(); |
38ff667b | 5495 | unlock: |
7b732a75 | 5496 | rcu_read_unlock(); |
37d81828 | 5497 | } |
82975c46 | 5498 | EXPORT_SYMBOL_GPL(perf_event_update_userpage); |
37d81828 | 5499 | |
9e3ed2d7 | 5500 | static vm_fault_t perf_mmap_fault(struct vm_fault *vmf) |
906010b2 | 5501 | { |
11bac800 | 5502 | struct perf_event *event = vmf->vma->vm_file->private_data; |
56de4e8f | 5503 | struct perf_buffer *rb; |
9e3ed2d7 | 5504 | vm_fault_t ret = VM_FAULT_SIGBUS; |
906010b2 PZ |
5505 | |
5506 | if (vmf->flags & FAULT_FLAG_MKWRITE) { | |
5507 | if (vmf->pgoff == 0) | |
5508 | ret = 0; | |
5509 | return ret; | |
5510 | } | |
5511 | ||
5512 | rcu_read_lock(); | |
76369139 FW |
5513 | rb = rcu_dereference(event->rb); |
5514 | if (!rb) | |
906010b2 PZ |
5515 | goto unlock; |
5516 | ||
5517 | if (vmf->pgoff && (vmf->flags & FAULT_FLAG_WRITE)) | |
5518 | goto unlock; | |
5519 | ||
76369139 | 5520 | vmf->page = perf_mmap_to_page(rb, vmf->pgoff); |
906010b2 PZ |
5521 | if (!vmf->page) |
5522 | goto unlock; | |
5523 | ||
5524 | get_page(vmf->page); | |
11bac800 | 5525 | vmf->page->mapping = vmf->vma->vm_file->f_mapping; |
906010b2 PZ |
5526 | vmf->page->index = vmf->pgoff; |
5527 | ||
5528 | ret = 0; | |
5529 | unlock: | |
5530 | rcu_read_unlock(); | |
5531 | ||
5532 | return ret; | |
5533 | } | |
5534 | ||
10c6db11 | 5535 | static void ring_buffer_attach(struct perf_event *event, |
56de4e8f | 5536 | struct perf_buffer *rb) |
10c6db11 | 5537 | { |
56de4e8f | 5538 | struct perf_buffer *old_rb = NULL; |
10c6db11 PZ |
5539 | unsigned long flags; |
5540 | ||
b69cf536 PZ |
5541 | if (event->rb) { |
5542 | /* | |
5543 | * Should be impossible, we set this when removing | |
5544 | * event->rb_entry and wait/clear when adding event->rb_entry. | |
5545 | */ | |
5546 | WARN_ON_ONCE(event->rcu_pending); | |
10c6db11 | 5547 | |
b69cf536 | 5548 | old_rb = event->rb; |
b69cf536 PZ |
5549 | spin_lock_irqsave(&old_rb->event_lock, flags); |
5550 | list_del_rcu(&event->rb_entry); | |
5551 | spin_unlock_irqrestore(&old_rb->event_lock, flags); | |
10c6db11 | 5552 | |
2f993cf0 ON |
5553 | event->rcu_batches = get_state_synchronize_rcu(); |
5554 | event->rcu_pending = 1; | |
b69cf536 | 5555 | } |
10c6db11 | 5556 | |
b69cf536 | 5557 | if (rb) { |
2f993cf0 ON |
5558 | if (event->rcu_pending) { |
5559 | cond_synchronize_rcu(event->rcu_batches); | |
5560 | event->rcu_pending = 0; | |
5561 | } | |
5562 | ||
b69cf536 PZ |
5563 | spin_lock_irqsave(&rb->event_lock, flags); |
5564 | list_add_rcu(&event->rb_entry, &rb->event_list); | |
5565 | spin_unlock_irqrestore(&rb->event_lock, flags); | |
5566 | } | |
5567 | ||
767ae086 AS |
5568 | /* |
5569 | * Avoid racing with perf_mmap_close(AUX): stop the event | |
5570 | * before swizzling the event::rb pointer; if it's getting | |
5571 | * unmapped, its aux_mmap_count will be 0 and it won't | |
5572 | * restart. See the comment in __perf_pmu_output_stop(). | |
5573 | * | |
5574 | * Data will inevitably be lost when set_output is done in | |
5575 | * mid-air, but then again, whoever does it like this is | |
5576 | * not in for the data anyway. | |
5577 | */ | |
5578 | if (has_aux(event)) | |
5579 | perf_event_stop(event, 0); | |
5580 | ||
b69cf536 PZ |
5581 | rcu_assign_pointer(event->rb, rb); |
5582 | ||
5583 | if (old_rb) { | |
5584 | ring_buffer_put(old_rb); | |
5585 | /* | |
5586 | * Since we detached before setting the new rb, so that we | |
5587 | * could attach the new rb, we could have missed a wakeup. | |
5588 | * Provide it now. | |
5589 | */ | |
5590 | wake_up_all(&event->waitq); | |
5591 | } | |
10c6db11 PZ |
5592 | } |
5593 | ||
5594 | static void ring_buffer_wakeup(struct perf_event *event) | |
5595 | { | |
56de4e8f | 5596 | struct perf_buffer *rb; |
10c6db11 PZ |
5597 | |
5598 | rcu_read_lock(); | |
5599 | rb = rcu_dereference(event->rb); | |
9bb5d40c PZ |
5600 | if (rb) { |
5601 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) | |
5602 | wake_up_all(&event->waitq); | |
5603 | } | |
10c6db11 PZ |
5604 | rcu_read_unlock(); |
5605 | } | |
5606 | ||
56de4e8f | 5607 | struct perf_buffer *ring_buffer_get(struct perf_event *event) |
7b732a75 | 5608 | { |
56de4e8f | 5609 | struct perf_buffer *rb; |
7b732a75 | 5610 | |
ac9721f3 | 5611 | rcu_read_lock(); |
76369139 FW |
5612 | rb = rcu_dereference(event->rb); |
5613 | if (rb) { | |
fecb8ed2 | 5614 | if (!refcount_inc_not_zero(&rb->refcount)) |
76369139 | 5615 | rb = NULL; |
ac9721f3 PZ |
5616 | } |
5617 | rcu_read_unlock(); | |
5618 | ||
76369139 | 5619 | return rb; |
ac9721f3 PZ |
5620 | } |
5621 | ||
56de4e8f | 5622 | void ring_buffer_put(struct perf_buffer *rb) |
ac9721f3 | 5623 | { |
fecb8ed2 | 5624 | if (!refcount_dec_and_test(&rb->refcount)) |
ac9721f3 | 5625 | return; |
7b732a75 | 5626 | |
9bb5d40c | 5627 | WARN_ON_ONCE(!list_empty(&rb->event_list)); |
10c6db11 | 5628 | |
76369139 | 5629 | call_rcu(&rb->rcu_head, rb_free_rcu); |
7b732a75 PZ |
5630 | } |
5631 | ||
5632 | static void perf_mmap_open(struct vm_area_struct *vma) | |
5633 | { | |
cdd6c482 | 5634 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 5635 | |
cdd6c482 | 5636 | atomic_inc(&event->mmap_count); |
9bb5d40c | 5637 | atomic_inc(&event->rb->mmap_count); |
1e0fb9ec | 5638 | |
45bfb2e5 PZ |
5639 | if (vma->vm_pgoff) |
5640 | atomic_inc(&event->rb->aux_mmap_count); | |
5641 | ||
1e0fb9ec | 5642 | if (event->pmu->event_mapped) |
bfe33492 | 5643 | event->pmu->event_mapped(event, vma->vm_mm); |
7b732a75 PZ |
5644 | } |
5645 | ||
95ff4ca2 AS |
5646 | static void perf_pmu_output_stop(struct perf_event *event); |
5647 | ||
9bb5d40c PZ |
5648 | /* |
5649 | * A buffer can be mmap()ed multiple times; either directly through the same | |
5650 | * event, or through other events by use of perf_event_set_output(). | |
5651 | * | |
5652 | * In order to undo the VM accounting done by perf_mmap() we need to destroy | |
5653 | * the buffer here, where we still have a VM context. This means we need | |
5654 | * to detach all events redirecting to us. | |
5655 | */ | |
7b732a75 PZ |
5656 | static void perf_mmap_close(struct vm_area_struct *vma) |
5657 | { | |
cdd6c482 | 5658 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 5659 | |
56de4e8f | 5660 | struct perf_buffer *rb = ring_buffer_get(event); |
9bb5d40c PZ |
5661 | struct user_struct *mmap_user = rb->mmap_user; |
5662 | int mmap_locked = rb->mmap_locked; | |
5663 | unsigned long size = perf_data_size(rb); | |
789f90fc | 5664 | |
1e0fb9ec | 5665 | if (event->pmu->event_unmapped) |
bfe33492 | 5666 | event->pmu->event_unmapped(event, vma->vm_mm); |
1e0fb9ec | 5667 | |
45bfb2e5 PZ |
5668 | /* |
5669 | * rb->aux_mmap_count will always drop before rb->mmap_count and | |
5670 | * event->mmap_count, so it is ok to use event->mmap_mutex to | |
5671 | * serialize with perf_mmap here. | |
5672 | */ | |
5673 | if (rb_has_aux(rb) && vma->vm_pgoff == rb->aux_pgoff && | |
5674 | atomic_dec_and_mutex_lock(&rb->aux_mmap_count, &event->mmap_mutex)) { | |
95ff4ca2 AS |
5675 | /* |
5676 | * Stop all AUX events that are writing to this buffer, | |
5677 | * so that we can free its AUX pages and corresponding PMU | |
5678 | * data. Note that after rb::aux_mmap_count dropped to zero, | |
5679 | * they won't start any more (see perf_aux_output_begin()). | |
5680 | */ | |
5681 | perf_pmu_output_stop(event); | |
5682 | ||
5683 | /* now it's safe to free the pages */ | |
36b3db03 AS |
5684 | atomic_long_sub(rb->aux_nr_pages - rb->aux_mmap_locked, &mmap_user->locked_vm); |
5685 | atomic64_sub(rb->aux_mmap_locked, &vma->vm_mm->pinned_vm); | |
45bfb2e5 | 5686 | |
95ff4ca2 | 5687 | /* this has to be the last one */ |
45bfb2e5 | 5688 | rb_free_aux(rb); |
ca3bb3d0 | 5689 | WARN_ON_ONCE(refcount_read(&rb->aux_refcount)); |
95ff4ca2 | 5690 | |
45bfb2e5 PZ |
5691 | mutex_unlock(&event->mmap_mutex); |
5692 | } | |
5693 | ||
9bb5d40c PZ |
5694 | atomic_dec(&rb->mmap_count); |
5695 | ||
5696 | if (!atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex)) | |
b69cf536 | 5697 | goto out_put; |
9bb5d40c | 5698 | |
b69cf536 | 5699 | ring_buffer_attach(event, NULL); |
9bb5d40c PZ |
5700 | mutex_unlock(&event->mmap_mutex); |
5701 | ||
5702 | /* If there's still other mmap()s of this buffer, we're done. */ | |
b69cf536 PZ |
5703 | if (atomic_read(&rb->mmap_count)) |
5704 | goto out_put; | |
ac9721f3 | 5705 | |
9bb5d40c PZ |
5706 | /* |
5707 | * No other mmap()s, detach from all other events that might redirect | |
5708 | * into the now unreachable buffer. Somewhat complicated by the | |
5709 | * fact that rb::event_lock otherwise nests inside mmap_mutex. | |
5710 | */ | |
5711 | again: | |
5712 | rcu_read_lock(); | |
5713 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) { | |
5714 | if (!atomic_long_inc_not_zero(&event->refcount)) { | |
5715 | /* | |
5716 | * This event is en-route to free_event() which will | |
5717 | * detach it and remove it from the list. | |
5718 | */ | |
5719 | continue; | |
5720 | } | |
5721 | rcu_read_unlock(); | |
789f90fc | 5722 | |
9bb5d40c PZ |
5723 | mutex_lock(&event->mmap_mutex); |
5724 | /* | |
5725 | * Check we didn't race with perf_event_set_output() which can | |
5726 | * swizzle the rb from under us while we were waiting to | |
5727 | * acquire mmap_mutex. | |
5728 | * | |
5729 | * If we find a different rb; ignore this event, a next | |
5730 | * iteration will no longer find it on the list. We have to | |
5731 | * still restart the iteration to make sure we're not now | |
5732 | * iterating the wrong list. | |
5733 | */ | |
b69cf536 PZ |
5734 | if (event->rb == rb) |
5735 | ring_buffer_attach(event, NULL); | |
5736 | ||
cdd6c482 | 5737 | mutex_unlock(&event->mmap_mutex); |
9bb5d40c | 5738 | put_event(event); |
ac9721f3 | 5739 | |
9bb5d40c PZ |
5740 | /* |
5741 | * Restart the iteration; either we're on the wrong list or | |
5742 | * destroyed its integrity by doing a deletion. | |
5743 | */ | |
5744 | goto again; | |
7b732a75 | 5745 | } |
9bb5d40c PZ |
5746 | rcu_read_unlock(); |
5747 | ||
5748 | /* | |
5749 | * It could be there's still a few 0-ref events on the list; they'll | |
5750 | * get cleaned up by free_event() -- they'll also still have their | |
5751 | * ref on the rb and will free it whenever they are done with it. | |
5752 | * | |
5753 | * Aside from that, this buffer is 'fully' detached and unmapped, | |
5754 | * undo the VM accounting. | |
5755 | */ | |
5756 | ||
d44248a4 SL |
5757 | atomic_long_sub((size >> PAGE_SHIFT) + 1 - mmap_locked, |
5758 | &mmap_user->locked_vm); | |
70f8a3ca | 5759 | atomic64_sub(mmap_locked, &vma->vm_mm->pinned_vm); |
9bb5d40c PZ |
5760 | free_uid(mmap_user); |
5761 | ||
b69cf536 | 5762 | out_put: |
9bb5d40c | 5763 | ring_buffer_put(rb); /* could be last */ |
37d81828 PM |
5764 | } |
5765 | ||
f0f37e2f | 5766 | static const struct vm_operations_struct perf_mmap_vmops = { |
43a21ea8 | 5767 | .open = perf_mmap_open, |
fca0c116 | 5768 | .close = perf_mmap_close, /* non mergeable */ |
43a21ea8 PZ |
5769 | .fault = perf_mmap_fault, |
5770 | .page_mkwrite = perf_mmap_fault, | |
37d81828 PM |
5771 | }; |
5772 | ||
5773 | static int perf_mmap(struct file *file, struct vm_area_struct *vma) | |
5774 | { | |
cdd6c482 | 5775 | struct perf_event *event = file->private_data; |
22a4f650 | 5776 | unsigned long user_locked, user_lock_limit; |
789f90fc | 5777 | struct user_struct *user = current_user(); |
56de4e8f | 5778 | struct perf_buffer *rb = NULL; |
22a4f650 | 5779 | unsigned long locked, lock_limit; |
7b732a75 PZ |
5780 | unsigned long vma_size; |
5781 | unsigned long nr_pages; | |
45bfb2e5 | 5782 | long user_extra = 0, extra = 0; |
d57e34fd | 5783 | int ret = 0, flags = 0; |
37d81828 | 5784 | |
c7920614 PZ |
5785 | /* |
5786 | * Don't allow mmap() of inherited per-task counters. This would | |
5787 | * create a performance issue due to all children writing to the | |
76369139 | 5788 | * same rb. |
c7920614 PZ |
5789 | */ |
5790 | if (event->cpu == -1 && event->attr.inherit) | |
5791 | return -EINVAL; | |
5792 | ||
43a21ea8 | 5793 | if (!(vma->vm_flags & VM_SHARED)) |
37d81828 | 5794 | return -EINVAL; |
7b732a75 | 5795 | |
da97e184 JFG |
5796 | ret = security_perf_event_read(event); |
5797 | if (ret) | |
5798 | return ret; | |
5799 | ||
7b732a75 | 5800 | vma_size = vma->vm_end - vma->vm_start; |
45bfb2e5 PZ |
5801 | |
5802 | if (vma->vm_pgoff == 0) { | |
5803 | nr_pages = (vma_size / PAGE_SIZE) - 1; | |
5804 | } else { | |
5805 | /* | |
5806 | * AUX area mapping: if rb->aux_nr_pages != 0, it's already | |
5807 | * mapped, all subsequent mappings should have the same size | |
5808 | * and offset. Must be above the normal perf buffer. | |
5809 | */ | |
5810 | u64 aux_offset, aux_size; | |
5811 | ||
5812 | if (!event->rb) | |
5813 | return -EINVAL; | |
5814 | ||
5815 | nr_pages = vma_size / PAGE_SIZE; | |
5816 | ||
5817 | mutex_lock(&event->mmap_mutex); | |
5818 | ret = -EINVAL; | |
5819 | ||
5820 | rb = event->rb; | |
5821 | if (!rb) | |
5822 | goto aux_unlock; | |
5823 | ||
6aa7de05 MR |
5824 | aux_offset = READ_ONCE(rb->user_page->aux_offset); |
5825 | aux_size = READ_ONCE(rb->user_page->aux_size); | |
45bfb2e5 PZ |
5826 | |
5827 | if (aux_offset < perf_data_size(rb) + PAGE_SIZE) | |
5828 | goto aux_unlock; | |
5829 | ||
5830 | if (aux_offset != vma->vm_pgoff << PAGE_SHIFT) | |
5831 | goto aux_unlock; | |
5832 | ||
5833 | /* already mapped with a different offset */ | |
5834 | if (rb_has_aux(rb) && rb->aux_pgoff != vma->vm_pgoff) | |
5835 | goto aux_unlock; | |
5836 | ||
5837 | if (aux_size != vma_size || aux_size != nr_pages * PAGE_SIZE) | |
5838 | goto aux_unlock; | |
5839 | ||
5840 | /* already mapped with a different size */ | |
5841 | if (rb_has_aux(rb) && rb->aux_nr_pages != nr_pages) | |
5842 | goto aux_unlock; | |
5843 | ||
5844 | if (!is_power_of_2(nr_pages)) | |
5845 | goto aux_unlock; | |
5846 | ||
5847 | if (!atomic_inc_not_zero(&rb->mmap_count)) | |
5848 | goto aux_unlock; | |
5849 | ||
5850 | if (rb_has_aux(rb)) { | |
5851 | atomic_inc(&rb->aux_mmap_count); | |
5852 | ret = 0; | |
5853 | goto unlock; | |
5854 | } | |
5855 | ||
5856 | atomic_set(&rb->aux_mmap_count, 1); | |
5857 | user_extra = nr_pages; | |
5858 | ||
5859 | goto accounting; | |
5860 | } | |
7b732a75 | 5861 | |
7730d865 | 5862 | /* |
76369139 | 5863 | * If we have rb pages ensure they're a power-of-two number, so we |
7730d865 PZ |
5864 | * can do bitmasks instead of modulo. |
5865 | */ | |
2ed11312 | 5866 | if (nr_pages != 0 && !is_power_of_2(nr_pages)) |
37d81828 PM |
5867 | return -EINVAL; |
5868 | ||
7b732a75 | 5869 | if (vma_size != PAGE_SIZE * (1 + nr_pages)) |
37d81828 PM |
5870 | return -EINVAL; |
5871 | ||
cdd6c482 | 5872 | WARN_ON_ONCE(event->ctx->parent_ctx); |
9bb5d40c | 5873 | again: |
cdd6c482 | 5874 | mutex_lock(&event->mmap_mutex); |
76369139 | 5875 | if (event->rb) { |
9bb5d40c | 5876 | if (event->rb->nr_pages != nr_pages) { |
ebb3c4c4 | 5877 | ret = -EINVAL; |
9bb5d40c PZ |
5878 | goto unlock; |
5879 | } | |
5880 | ||
5881 | if (!atomic_inc_not_zero(&event->rb->mmap_count)) { | |
5882 | /* | |
5883 | * Raced against perf_mmap_close() through | |
5884 | * perf_event_set_output(). Try again, hope for better | |
5885 | * luck. | |
5886 | */ | |
5887 | mutex_unlock(&event->mmap_mutex); | |
5888 | goto again; | |
5889 | } | |
5890 | ||
ebb3c4c4 PZ |
5891 | goto unlock; |
5892 | } | |
5893 | ||
789f90fc | 5894 | user_extra = nr_pages + 1; |
45bfb2e5 PZ |
5895 | |
5896 | accounting: | |
cdd6c482 | 5897 | user_lock_limit = sysctl_perf_event_mlock >> (PAGE_SHIFT - 10); |
a3862d3f IM |
5898 | |
5899 | /* | |
5900 | * Increase the limit linearly with more CPUs: | |
5901 | */ | |
5902 | user_lock_limit *= num_online_cpus(); | |
5903 | ||
00346155 SL |
5904 | user_locked = atomic_long_read(&user->locked_vm); |
5905 | ||
5906 | /* | |
5907 | * sysctl_perf_event_mlock may have changed, so that | |
5908 | * user->locked_vm > user_lock_limit | |
5909 | */ | |
5910 | if (user_locked > user_lock_limit) | |
5911 | user_locked = user_lock_limit; | |
5912 | user_locked += user_extra; | |
c5078f78 | 5913 | |
c4b75479 | 5914 | if (user_locked > user_lock_limit) { |
d44248a4 SL |
5915 | /* |
5916 | * charge locked_vm until it hits user_lock_limit; | |
5917 | * charge the rest from pinned_vm | |
5918 | */ | |
789f90fc | 5919 | extra = user_locked - user_lock_limit; |
d44248a4 SL |
5920 | user_extra -= extra; |
5921 | } | |
7b732a75 | 5922 | |
78d7d407 | 5923 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
7b732a75 | 5924 | lock_limit >>= PAGE_SHIFT; |
70f8a3ca | 5925 | locked = atomic64_read(&vma->vm_mm->pinned_vm) + extra; |
7b732a75 | 5926 | |
da97e184 | 5927 | if ((locked > lock_limit) && perf_is_paranoid() && |
459ec28a | 5928 | !capable(CAP_IPC_LOCK)) { |
ebb3c4c4 PZ |
5929 | ret = -EPERM; |
5930 | goto unlock; | |
5931 | } | |
7b732a75 | 5932 | |
45bfb2e5 | 5933 | WARN_ON(!rb && event->rb); |
906010b2 | 5934 | |
d57e34fd | 5935 | if (vma->vm_flags & VM_WRITE) |
76369139 | 5936 | flags |= RING_BUFFER_WRITABLE; |
d57e34fd | 5937 | |
76369139 | 5938 | if (!rb) { |
45bfb2e5 PZ |
5939 | rb = rb_alloc(nr_pages, |
5940 | event->attr.watermark ? event->attr.wakeup_watermark : 0, | |
5941 | event->cpu, flags); | |
26cb63ad | 5942 | |
45bfb2e5 PZ |
5943 | if (!rb) { |
5944 | ret = -ENOMEM; | |
5945 | goto unlock; | |
5946 | } | |
43a21ea8 | 5947 | |
45bfb2e5 PZ |
5948 | atomic_set(&rb->mmap_count, 1); |
5949 | rb->mmap_user = get_current_user(); | |
5950 | rb->mmap_locked = extra; | |
26cb63ad | 5951 | |
45bfb2e5 | 5952 | ring_buffer_attach(event, rb); |
ac9721f3 | 5953 | |
45bfb2e5 PZ |
5954 | perf_event_init_userpage(event); |
5955 | perf_event_update_userpage(event); | |
5956 | } else { | |
1a594131 AS |
5957 | ret = rb_alloc_aux(rb, event, vma->vm_pgoff, nr_pages, |
5958 | event->attr.aux_watermark, flags); | |
45bfb2e5 PZ |
5959 | if (!ret) |
5960 | rb->aux_mmap_locked = extra; | |
5961 | } | |
9a0f05cb | 5962 | |
ebb3c4c4 | 5963 | unlock: |
45bfb2e5 PZ |
5964 | if (!ret) { |
5965 | atomic_long_add(user_extra, &user->locked_vm); | |
70f8a3ca | 5966 | atomic64_add(extra, &vma->vm_mm->pinned_vm); |
45bfb2e5 | 5967 | |
ac9721f3 | 5968 | atomic_inc(&event->mmap_count); |
45bfb2e5 PZ |
5969 | } else if (rb) { |
5970 | atomic_dec(&rb->mmap_count); | |
5971 | } | |
5972 | aux_unlock: | |
cdd6c482 | 5973 | mutex_unlock(&event->mmap_mutex); |
37d81828 | 5974 | |
9bb5d40c PZ |
5975 | /* |
5976 | * Since pinned accounting is per vm we cannot allow fork() to copy our | |
5977 | * vma. | |
5978 | */ | |
26cb63ad | 5979 | vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND | VM_DONTDUMP; |
37d81828 | 5980 | vma->vm_ops = &perf_mmap_vmops; |
7b732a75 | 5981 | |
1e0fb9ec | 5982 | if (event->pmu->event_mapped) |
bfe33492 | 5983 | event->pmu->event_mapped(event, vma->vm_mm); |
1e0fb9ec | 5984 | |
7b732a75 | 5985 | return ret; |
37d81828 PM |
5986 | } |
5987 | ||
3c446b3d PZ |
5988 | static int perf_fasync(int fd, struct file *filp, int on) |
5989 | { | |
496ad9aa | 5990 | struct inode *inode = file_inode(filp); |
cdd6c482 | 5991 | struct perf_event *event = filp->private_data; |
3c446b3d PZ |
5992 | int retval; |
5993 | ||
5955102c | 5994 | inode_lock(inode); |
cdd6c482 | 5995 | retval = fasync_helper(fd, filp, on, &event->fasync); |
5955102c | 5996 | inode_unlock(inode); |
3c446b3d PZ |
5997 | |
5998 | if (retval < 0) | |
5999 | return retval; | |
6000 | ||
6001 | return 0; | |
6002 | } | |
6003 | ||
0793a61d | 6004 | static const struct file_operations perf_fops = { |
3326c1ce | 6005 | .llseek = no_llseek, |
0793a61d TG |
6006 | .release = perf_release, |
6007 | .read = perf_read, | |
6008 | .poll = perf_poll, | |
d859e29f | 6009 | .unlocked_ioctl = perf_ioctl, |
b3f20785 | 6010 | .compat_ioctl = perf_compat_ioctl, |
37d81828 | 6011 | .mmap = perf_mmap, |
3c446b3d | 6012 | .fasync = perf_fasync, |
0793a61d TG |
6013 | }; |
6014 | ||
925d519a | 6015 | /* |
cdd6c482 | 6016 | * Perf event wakeup |
925d519a PZ |
6017 | * |
6018 | * If there's data, ensure we set the poll() state and publish everything | |
6019 | * to user-space before waking everybody up. | |
6020 | */ | |
6021 | ||
fed66e2c PZ |
6022 | static inline struct fasync_struct **perf_event_fasync(struct perf_event *event) |
6023 | { | |
6024 | /* only the parent has fasync state */ | |
6025 | if (event->parent) | |
6026 | event = event->parent; | |
6027 | return &event->fasync; | |
6028 | } | |
6029 | ||
cdd6c482 | 6030 | void perf_event_wakeup(struct perf_event *event) |
925d519a | 6031 | { |
10c6db11 | 6032 | ring_buffer_wakeup(event); |
4c9e2542 | 6033 | |
cdd6c482 | 6034 | if (event->pending_kill) { |
fed66e2c | 6035 | kill_fasync(perf_event_fasync(event), SIGIO, event->pending_kill); |
cdd6c482 | 6036 | event->pending_kill = 0; |
4c9e2542 | 6037 | } |
925d519a PZ |
6038 | } |
6039 | ||
1d54ad94 PZ |
6040 | static void perf_pending_event_disable(struct perf_event *event) |
6041 | { | |
6042 | int cpu = READ_ONCE(event->pending_disable); | |
6043 | ||
6044 | if (cpu < 0) | |
6045 | return; | |
6046 | ||
6047 | if (cpu == smp_processor_id()) { | |
6048 | WRITE_ONCE(event->pending_disable, -1); | |
6049 | perf_event_disable_local(event); | |
6050 | return; | |
6051 | } | |
6052 | ||
6053 | /* | |
6054 | * CPU-A CPU-B | |
6055 | * | |
6056 | * perf_event_disable_inatomic() | |
6057 | * @pending_disable = CPU-A; | |
6058 | * irq_work_queue(); | |
6059 | * | |
6060 | * sched-out | |
6061 | * @pending_disable = -1; | |
6062 | * | |
6063 | * sched-in | |
6064 | * perf_event_disable_inatomic() | |
6065 | * @pending_disable = CPU-B; | |
6066 | * irq_work_queue(); // FAILS | |
6067 | * | |
6068 | * irq_work_run() | |
6069 | * perf_pending_event() | |
6070 | * | |
6071 | * But the event runs on CPU-B and wants disabling there. | |
6072 | */ | |
6073 | irq_work_queue_on(&event->pending, cpu); | |
6074 | } | |
6075 | ||
e360adbe | 6076 | static void perf_pending_event(struct irq_work *entry) |
79f14641 | 6077 | { |
1d54ad94 | 6078 | struct perf_event *event = container_of(entry, struct perf_event, pending); |
d525211f PZ |
6079 | int rctx; |
6080 | ||
6081 | rctx = perf_swevent_get_recursion_context(); | |
6082 | /* | |
6083 | * If we 'fail' here, that's OK, it means recursion is already disabled | |
6084 | * and we won't recurse 'further'. | |
6085 | */ | |
79f14641 | 6086 | |
1d54ad94 | 6087 | perf_pending_event_disable(event); |
79f14641 | 6088 | |
cdd6c482 IM |
6089 | if (event->pending_wakeup) { |
6090 | event->pending_wakeup = 0; | |
6091 | perf_event_wakeup(event); | |
79f14641 | 6092 | } |
d525211f PZ |
6093 | |
6094 | if (rctx >= 0) | |
6095 | perf_swevent_put_recursion_context(rctx); | |
79f14641 PZ |
6096 | } |
6097 | ||
39447b38 ZY |
6098 | /* |
6099 | * We assume there is only KVM supporting the callbacks. | |
6100 | * Later on, we might change it to a list if there is | |
6101 | * another virtualization implementation supporting the callbacks. | |
6102 | */ | |
6103 | struct perf_guest_info_callbacks *perf_guest_cbs; | |
6104 | ||
6105 | int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
6106 | { | |
6107 | perf_guest_cbs = cbs; | |
6108 | return 0; | |
6109 | } | |
6110 | EXPORT_SYMBOL_GPL(perf_register_guest_info_callbacks); | |
6111 | ||
6112 | int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
6113 | { | |
6114 | perf_guest_cbs = NULL; | |
6115 | return 0; | |
6116 | } | |
6117 | EXPORT_SYMBOL_GPL(perf_unregister_guest_info_callbacks); | |
6118 | ||
4018994f JO |
6119 | static void |
6120 | perf_output_sample_regs(struct perf_output_handle *handle, | |
6121 | struct pt_regs *regs, u64 mask) | |
6122 | { | |
6123 | int bit; | |
29dd3288 | 6124 | DECLARE_BITMAP(_mask, 64); |
4018994f | 6125 | |
29dd3288 MS |
6126 | bitmap_from_u64(_mask, mask); |
6127 | for_each_set_bit(bit, _mask, sizeof(mask) * BITS_PER_BYTE) { | |
4018994f JO |
6128 | u64 val; |
6129 | ||
6130 | val = perf_reg_value(regs, bit); | |
6131 | perf_output_put(handle, val); | |
6132 | } | |
6133 | } | |
6134 | ||
60e2364e | 6135 | static void perf_sample_regs_user(struct perf_regs *regs_user, |
88a7c26a AL |
6136 | struct pt_regs *regs, |
6137 | struct pt_regs *regs_user_copy) | |
4018994f | 6138 | { |
88a7c26a AL |
6139 | if (user_mode(regs)) { |
6140 | regs_user->abi = perf_reg_abi(current); | |
2565711f | 6141 | regs_user->regs = regs; |
085ebfe9 | 6142 | } else if (!(current->flags & PF_KTHREAD)) { |
88a7c26a | 6143 | perf_get_regs_user(regs_user, regs, regs_user_copy); |
2565711f PZ |
6144 | } else { |
6145 | regs_user->abi = PERF_SAMPLE_REGS_ABI_NONE; | |
6146 | regs_user->regs = NULL; | |
4018994f JO |
6147 | } |
6148 | } | |
6149 | ||
60e2364e SE |
6150 | static void perf_sample_regs_intr(struct perf_regs *regs_intr, |
6151 | struct pt_regs *regs) | |
6152 | { | |
6153 | regs_intr->regs = regs; | |
6154 | regs_intr->abi = perf_reg_abi(current); | |
6155 | } | |
6156 | ||
6157 | ||
c5ebcedb JO |
6158 | /* |
6159 | * Get remaining task size from user stack pointer. | |
6160 | * | |
6161 | * It'd be better to take stack vma map and limit this more | |
9f014e3a | 6162 | * precisely, but there's no way to get it safely under interrupt, |
c5ebcedb JO |
6163 | * so using TASK_SIZE as limit. |
6164 | */ | |
6165 | static u64 perf_ustack_task_size(struct pt_regs *regs) | |
6166 | { | |
6167 | unsigned long addr = perf_user_stack_pointer(regs); | |
6168 | ||
6169 | if (!addr || addr >= TASK_SIZE) | |
6170 | return 0; | |
6171 | ||
6172 | return TASK_SIZE - addr; | |
6173 | } | |
6174 | ||
6175 | static u16 | |
6176 | perf_sample_ustack_size(u16 stack_size, u16 header_size, | |
6177 | struct pt_regs *regs) | |
6178 | { | |
6179 | u64 task_size; | |
6180 | ||
6181 | /* No regs, no stack pointer, no dump. */ | |
6182 | if (!regs) | |
6183 | return 0; | |
6184 | ||
6185 | /* | |
6186 | * Check if we fit in with the requested stack size into the: | |
6187 | * - TASK_SIZE | |
6188 | * If we don't, we limit the size to the TASK_SIZE. | |
6189 | * | |
6190 | * - remaining sample size | |
6191 | * If we don't, we customize the stack size to | |
6192 | * fit in to the remaining sample size. | |
6193 | */ | |
6194 | ||
6195 | task_size = min((u64) USHRT_MAX, perf_ustack_task_size(regs)); | |
6196 | stack_size = min(stack_size, (u16) task_size); | |
6197 | ||
6198 | /* Current header size plus static size and dynamic size. */ | |
6199 | header_size += 2 * sizeof(u64); | |
6200 | ||
6201 | /* Do we fit in with the current stack dump size? */ | |
6202 | if ((u16) (header_size + stack_size) < header_size) { | |
6203 | /* | |
6204 | * If we overflow the maximum size for the sample, | |
6205 | * we customize the stack dump size to fit in. | |
6206 | */ | |
6207 | stack_size = USHRT_MAX - header_size - sizeof(u64); | |
6208 | stack_size = round_up(stack_size, sizeof(u64)); | |
6209 | } | |
6210 | ||
6211 | return stack_size; | |
6212 | } | |
6213 | ||
6214 | static void | |
6215 | perf_output_sample_ustack(struct perf_output_handle *handle, u64 dump_size, | |
6216 | struct pt_regs *regs) | |
6217 | { | |
6218 | /* Case of a kernel thread, nothing to dump */ | |
6219 | if (!regs) { | |
6220 | u64 size = 0; | |
6221 | perf_output_put(handle, size); | |
6222 | } else { | |
6223 | unsigned long sp; | |
6224 | unsigned int rem; | |
6225 | u64 dyn_size; | |
02e18447 | 6226 | mm_segment_t fs; |
c5ebcedb JO |
6227 | |
6228 | /* | |
6229 | * We dump: | |
6230 | * static size | |
6231 | * - the size requested by user or the best one we can fit | |
6232 | * in to the sample max size | |
6233 | * data | |
6234 | * - user stack dump data | |
6235 | * dynamic size | |
6236 | * - the actual dumped size | |
6237 | */ | |
6238 | ||
6239 | /* Static size. */ | |
6240 | perf_output_put(handle, dump_size); | |
6241 | ||
6242 | /* Data. */ | |
6243 | sp = perf_user_stack_pointer(regs); | |
02e18447 YC |
6244 | fs = get_fs(); |
6245 | set_fs(USER_DS); | |
c5ebcedb | 6246 | rem = __output_copy_user(handle, (void *) sp, dump_size); |
02e18447 | 6247 | set_fs(fs); |
c5ebcedb JO |
6248 | dyn_size = dump_size - rem; |
6249 | ||
6250 | perf_output_skip(handle, rem); | |
6251 | ||
6252 | /* Dynamic size. */ | |
6253 | perf_output_put(handle, dyn_size); | |
6254 | } | |
6255 | } | |
6256 | ||
a4faf00d AS |
6257 | static unsigned long perf_prepare_sample_aux(struct perf_event *event, |
6258 | struct perf_sample_data *data, | |
6259 | size_t size) | |
6260 | { | |
6261 | struct perf_event *sampler = event->aux_event; | |
56de4e8f | 6262 | struct perf_buffer *rb; |
a4faf00d AS |
6263 | |
6264 | data->aux_size = 0; | |
6265 | ||
6266 | if (!sampler) | |
6267 | goto out; | |
6268 | ||
6269 | if (WARN_ON_ONCE(READ_ONCE(sampler->state) != PERF_EVENT_STATE_ACTIVE)) | |
6270 | goto out; | |
6271 | ||
6272 | if (WARN_ON_ONCE(READ_ONCE(sampler->oncpu) != smp_processor_id())) | |
6273 | goto out; | |
6274 | ||
6275 | rb = ring_buffer_get(sampler->parent ? sampler->parent : sampler); | |
6276 | if (!rb) | |
6277 | goto out; | |
6278 | ||
6279 | /* | |
6280 | * If this is an NMI hit inside sampling code, don't take | |
6281 | * the sample. See also perf_aux_sample_output(). | |
6282 | */ | |
6283 | if (READ_ONCE(rb->aux_in_sampling)) { | |
6284 | data->aux_size = 0; | |
6285 | } else { | |
6286 | size = min_t(size_t, size, perf_aux_size(rb)); | |
6287 | data->aux_size = ALIGN(size, sizeof(u64)); | |
6288 | } | |
6289 | ring_buffer_put(rb); | |
6290 | ||
6291 | out: | |
6292 | return data->aux_size; | |
6293 | } | |
6294 | ||
56de4e8f | 6295 | long perf_pmu_snapshot_aux(struct perf_buffer *rb, |
a4faf00d AS |
6296 | struct perf_event *event, |
6297 | struct perf_output_handle *handle, | |
6298 | unsigned long size) | |
6299 | { | |
6300 | unsigned long flags; | |
6301 | long ret; | |
6302 | ||
6303 | /* | |
6304 | * Normal ->start()/->stop() callbacks run in IRQ mode in scheduler | |
6305 | * paths. If we start calling them in NMI context, they may race with | |
6306 | * the IRQ ones, that is, for example, re-starting an event that's just | |
6307 | * been stopped, which is why we're using a separate callback that | |
6308 | * doesn't change the event state. | |
6309 | * | |
6310 | * IRQs need to be disabled to prevent IPIs from racing with us. | |
6311 | */ | |
6312 | local_irq_save(flags); | |
6313 | /* | |
6314 | * Guard against NMI hits inside the critical section; | |
6315 | * see also perf_prepare_sample_aux(). | |
6316 | */ | |
6317 | WRITE_ONCE(rb->aux_in_sampling, 1); | |
6318 | barrier(); | |
6319 | ||
6320 | ret = event->pmu->snapshot_aux(event, handle, size); | |
6321 | ||
6322 | barrier(); | |
6323 | WRITE_ONCE(rb->aux_in_sampling, 0); | |
6324 | local_irq_restore(flags); | |
6325 | ||
6326 | return ret; | |
6327 | } | |
6328 | ||
6329 | static void perf_aux_sample_output(struct perf_event *event, | |
6330 | struct perf_output_handle *handle, | |
6331 | struct perf_sample_data *data) | |
6332 | { | |
6333 | struct perf_event *sampler = event->aux_event; | |
56de4e8f | 6334 | struct perf_buffer *rb; |
a4faf00d | 6335 | unsigned long pad; |
a4faf00d AS |
6336 | long size; |
6337 | ||
6338 | if (WARN_ON_ONCE(!sampler || !data->aux_size)) | |
6339 | return; | |
6340 | ||
6341 | rb = ring_buffer_get(sampler->parent ? sampler->parent : sampler); | |
6342 | if (!rb) | |
6343 | return; | |
6344 | ||
6345 | size = perf_pmu_snapshot_aux(rb, sampler, handle, data->aux_size); | |
6346 | ||
6347 | /* | |
6348 | * An error here means that perf_output_copy() failed (returned a | |
6349 | * non-zero surplus that it didn't copy), which in its current | |
6350 | * enlightened implementation is not possible. If that changes, we'd | |
6351 | * like to know. | |
6352 | */ | |
6353 | if (WARN_ON_ONCE(size < 0)) | |
6354 | goto out_put; | |
6355 | ||
6356 | /* | |
6357 | * The pad comes from ALIGN()ing data->aux_size up to u64 in | |
6358 | * perf_prepare_sample_aux(), so should not be more than that. | |
6359 | */ | |
6360 | pad = data->aux_size - size; | |
6361 | if (WARN_ON_ONCE(pad >= sizeof(u64))) | |
6362 | pad = 8; | |
6363 | ||
6364 | if (pad) { | |
6365 | u64 zero = 0; | |
6366 | perf_output_copy(handle, &zero, pad); | |
6367 | } | |
6368 | ||
6369 | out_put: | |
6370 | ring_buffer_put(rb); | |
6371 | } | |
6372 | ||
c980d109 ACM |
6373 | static void __perf_event_header__init_id(struct perf_event_header *header, |
6374 | struct perf_sample_data *data, | |
6375 | struct perf_event *event) | |
6844c09d ACM |
6376 | { |
6377 | u64 sample_type = event->attr.sample_type; | |
6378 | ||
6379 | data->type = sample_type; | |
6380 | header->size += event->id_header_size; | |
6381 | ||
6382 | if (sample_type & PERF_SAMPLE_TID) { | |
6383 | /* namespace issues */ | |
6384 | data->tid_entry.pid = perf_event_pid(event, current); | |
6385 | data->tid_entry.tid = perf_event_tid(event, current); | |
6386 | } | |
6387 | ||
6388 | if (sample_type & PERF_SAMPLE_TIME) | |
34f43927 | 6389 | data->time = perf_event_clock(event); |
6844c09d | 6390 | |
ff3d527c | 6391 | if (sample_type & (PERF_SAMPLE_ID | PERF_SAMPLE_IDENTIFIER)) |
6844c09d ACM |
6392 | data->id = primary_event_id(event); |
6393 | ||
6394 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6395 | data->stream_id = event->id; | |
6396 | ||
6397 | if (sample_type & PERF_SAMPLE_CPU) { | |
6398 | data->cpu_entry.cpu = raw_smp_processor_id(); | |
6399 | data->cpu_entry.reserved = 0; | |
6400 | } | |
6401 | } | |
6402 | ||
76369139 FW |
6403 | void perf_event_header__init_id(struct perf_event_header *header, |
6404 | struct perf_sample_data *data, | |
6405 | struct perf_event *event) | |
c980d109 ACM |
6406 | { |
6407 | if (event->attr.sample_id_all) | |
6408 | __perf_event_header__init_id(header, data, event); | |
6409 | } | |
6410 | ||
6411 | static void __perf_event__output_id_sample(struct perf_output_handle *handle, | |
6412 | struct perf_sample_data *data) | |
6413 | { | |
6414 | u64 sample_type = data->type; | |
6415 | ||
6416 | if (sample_type & PERF_SAMPLE_TID) | |
6417 | perf_output_put(handle, data->tid_entry); | |
6418 | ||
6419 | if (sample_type & PERF_SAMPLE_TIME) | |
6420 | perf_output_put(handle, data->time); | |
6421 | ||
6422 | if (sample_type & PERF_SAMPLE_ID) | |
6423 | perf_output_put(handle, data->id); | |
6424 | ||
6425 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6426 | perf_output_put(handle, data->stream_id); | |
6427 | ||
6428 | if (sample_type & PERF_SAMPLE_CPU) | |
6429 | perf_output_put(handle, data->cpu_entry); | |
ff3d527c AH |
6430 | |
6431 | if (sample_type & PERF_SAMPLE_IDENTIFIER) | |
6432 | perf_output_put(handle, data->id); | |
c980d109 ACM |
6433 | } |
6434 | ||
76369139 FW |
6435 | void perf_event__output_id_sample(struct perf_event *event, |
6436 | struct perf_output_handle *handle, | |
6437 | struct perf_sample_data *sample) | |
c980d109 ACM |
6438 | { |
6439 | if (event->attr.sample_id_all) | |
6440 | __perf_event__output_id_sample(handle, sample); | |
6441 | } | |
6442 | ||
3dab77fb | 6443 | static void perf_output_read_one(struct perf_output_handle *handle, |
eed01528 SE |
6444 | struct perf_event *event, |
6445 | u64 enabled, u64 running) | |
3dab77fb | 6446 | { |
cdd6c482 | 6447 | u64 read_format = event->attr.read_format; |
3dab77fb PZ |
6448 | u64 values[4]; |
6449 | int n = 0; | |
6450 | ||
b5e58793 | 6451 | values[n++] = perf_event_count(event); |
3dab77fb | 6452 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { |
eed01528 | 6453 | values[n++] = enabled + |
cdd6c482 | 6454 | atomic64_read(&event->child_total_time_enabled); |
3dab77fb PZ |
6455 | } |
6456 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { | |
eed01528 | 6457 | values[n++] = running + |
cdd6c482 | 6458 | atomic64_read(&event->child_total_time_running); |
3dab77fb PZ |
6459 | } |
6460 | if (read_format & PERF_FORMAT_ID) | |
cdd6c482 | 6461 | values[n++] = primary_event_id(event); |
3dab77fb | 6462 | |
76369139 | 6463 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
6464 | } |
6465 | ||
3dab77fb | 6466 | static void perf_output_read_group(struct perf_output_handle *handle, |
eed01528 SE |
6467 | struct perf_event *event, |
6468 | u64 enabled, u64 running) | |
3dab77fb | 6469 | { |
cdd6c482 IM |
6470 | struct perf_event *leader = event->group_leader, *sub; |
6471 | u64 read_format = event->attr.read_format; | |
3dab77fb PZ |
6472 | u64 values[5]; |
6473 | int n = 0; | |
6474 | ||
6475 | values[n++] = 1 + leader->nr_siblings; | |
6476 | ||
6477 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
eed01528 | 6478 | values[n++] = enabled; |
3dab77fb PZ |
6479 | |
6480 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
eed01528 | 6481 | values[n++] = running; |
3dab77fb | 6482 | |
9e5b127d PZ |
6483 | if ((leader != event) && |
6484 | (leader->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
6485 | leader->pmu->read(leader); |
6486 | ||
b5e58793 | 6487 | values[n++] = perf_event_count(leader); |
3dab77fb | 6488 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 6489 | values[n++] = primary_event_id(leader); |
3dab77fb | 6490 | |
76369139 | 6491 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb | 6492 | |
edb39592 | 6493 | for_each_sibling_event(sub, leader) { |
3dab77fb PZ |
6494 | n = 0; |
6495 | ||
6f5ab001 JO |
6496 | if ((sub != event) && |
6497 | (sub->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
6498 | sub->pmu->read(sub); |
6499 | ||
b5e58793 | 6500 | values[n++] = perf_event_count(sub); |
3dab77fb | 6501 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 6502 | values[n++] = primary_event_id(sub); |
3dab77fb | 6503 | |
76369139 | 6504 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
6505 | } |
6506 | } | |
6507 | ||
eed01528 SE |
6508 | #define PERF_FORMAT_TOTAL_TIMES (PERF_FORMAT_TOTAL_TIME_ENABLED|\ |
6509 | PERF_FORMAT_TOTAL_TIME_RUNNING) | |
6510 | ||
ba5213ae PZ |
6511 | /* |
6512 | * XXX PERF_SAMPLE_READ vs inherited events seems difficult. | |
6513 | * | |
6514 | * The problem is that its both hard and excessively expensive to iterate the | |
6515 | * child list, not to mention that its impossible to IPI the children running | |
6516 | * on another CPU, from interrupt/NMI context. | |
6517 | */ | |
3dab77fb | 6518 | static void perf_output_read(struct perf_output_handle *handle, |
cdd6c482 | 6519 | struct perf_event *event) |
3dab77fb | 6520 | { |
e3f3541c | 6521 | u64 enabled = 0, running = 0, now; |
eed01528 SE |
6522 | u64 read_format = event->attr.read_format; |
6523 | ||
6524 | /* | |
6525 | * compute total_time_enabled, total_time_running | |
6526 | * based on snapshot values taken when the event | |
6527 | * was last scheduled in. | |
6528 | * | |
6529 | * we cannot simply called update_context_time() | |
6530 | * because of locking issue as we are called in | |
6531 | * NMI context | |
6532 | */ | |
c4794295 | 6533 | if (read_format & PERF_FORMAT_TOTAL_TIMES) |
e3f3541c | 6534 | calc_timer_values(event, &now, &enabled, &running); |
eed01528 | 6535 | |
cdd6c482 | 6536 | if (event->attr.read_format & PERF_FORMAT_GROUP) |
eed01528 | 6537 | perf_output_read_group(handle, event, enabled, running); |
3dab77fb | 6538 | else |
eed01528 | 6539 | perf_output_read_one(handle, event, enabled, running); |
3dab77fb PZ |
6540 | } |
6541 | ||
bbfd5e4f KL |
6542 | static inline bool perf_sample_save_hw_index(struct perf_event *event) |
6543 | { | |
6544 | return event->attr.branch_sample_type & PERF_SAMPLE_BRANCH_HW_INDEX; | |
6545 | } | |
6546 | ||
5622f295 MM |
6547 | void perf_output_sample(struct perf_output_handle *handle, |
6548 | struct perf_event_header *header, | |
6549 | struct perf_sample_data *data, | |
cdd6c482 | 6550 | struct perf_event *event) |
5622f295 MM |
6551 | { |
6552 | u64 sample_type = data->type; | |
6553 | ||
6554 | perf_output_put(handle, *header); | |
6555 | ||
ff3d527c AH |
6556 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
6557 | perf_output_put(handle, data->id); | |
6558 | ||
5622f295 MM |
6559 | if (sample_type & PERF_SAMPLE_IP) |
6560 | perf_output_put(handle, data->ip); | |
6561 | ||
6562 | if (sample_type & PERF_SAMPLE_TID) | |
6563 | perf_output_put(handle, data->tid_entry); | |
6564 | ||
6565 | if (sample_type & PERF_SAMPLE_TIME) | |
6566 | perf_output_put(handle, data->time); | |
6567 | ||
6568 | if (sample_type & PERF_SAMPLE_ADDR) | |
6569 | perf_output_put(handle, data->addr); | |
6570 | ||
6571 | if (sample_type & PERF_SAMPLE_ID) | |
6572 | perf_output_put(handle, data->id); | |
6573 | ||
6574 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6575 | perf_output_put(handle, data->stream_id); | |
6576 | ||
6577 | if (sample_type & PERF_SAMPLE_CPU) | |
6578 | perf_output_put(handle, data->cpu_entry); | |
6579 | ||
6580 | if (sample_type & PERF_SAMPLE_PERIOD) | |
6581 | perf_output_put(handle, data->period); | |
6582 | ||
6583 | if (sample_type & PERF_SAMPLE_READ) | |
cdd6c482 | 6584 | perf_output_read(handle, event); |
5622f295 MM |
6585 | |
6586 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { | |
99e818cc | 6587 | int size = 1; |
5622f295 | 6588 | |
99e818cc JO |
6589 | size += data->callchain->nr; |
6590 | size *= sizeof(u64); | |
6591 | __output_copy(handle, data->callchain, size); | |
5622f295 MM |
6592 | } |
6593 | ||
6594 | if (sample_type & PERF_SAMPLE_RAW) { | |
7e3f977e DB |
6595 | struct perf_raw_record *raw = data->raw; |
6596 | ||
6597 | if (raw) { | |
6598 | struct perf_raw_frag *frag = &raw->frag; | |
6599 | ||
6600 | perf_output_put(handle, raw->size); | |
6601 | do { | |
6602 | if (frag->copy) { | |
6603 | __output_custom(handle, frag->copy, | |
6604 | frag->data, frag->size); | |
6605 | } else { | |
6606 | __output_copy(handle, frag->data, | |
6607 | frag->size); | |
6608 | } | |
6609 | if (perf_raw_frag_last(frag)) | |
6610 | break; | |
6611 | frag = frag->next; | |
6612 | } while (1); | |
6613 | if (frag->pad) | |
6614 | __output_skip(handle, NULL, frag->pad); | |
5622f295 MM |
6615 | } else { |
6616 | struct { | |
6617 | u32 size; | |
6618 | u32 data; | |
6619 | } raw = { | |
6620 | .size = sizeof(u32), | |
6621 | .data = 0, | |
6622 | }; | |
6623 | perf_output_put(handle, raw); | |
6624 | } | |
6625 | } | |
a7ac67ea | 6626 | |
bce38cd5 SE |
6627 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { |
6628 | if (data->br_stack) { | |
6629 | size_t size; | |
6630 | ||
6631 | size = data->br_stack->nr | |
6632 | * sizeof(struct perf_branch_entry); | |
6633 | ||
6634 | perf_output_put(handle, data->br_stack->nr); | |
bbfd5e4f KL |
6635 | if (perf_sample_save_hw_index(event)) |
6636 | perf_output_put(handle, data->br_stack->hw_idx); | |
bce38cd5 SE |
6637 | perf_output_copy(handle, data->br_stack->entries, size); |
6638 | } else { | |
6639 | /* | |
6640 | * we always store at least the value of nr | |
6641 | */ | |
6642 | u64 nr = 0; | |
6643 | perf_output_put(handle, nr); | |
6644 | } | |
6645 | } | |
4018994f JO |
6646 | |
6647 | if (sample_type & PERF_SAMPLE_REGS_USER) { | |
6648 | u64 abi = data->regs_user.abi; | |
6649 | ||
6650 | /* | |
6651 | * If there are no regs to dump, notice it through | |
6652 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
6653 | */ | |
6654 | perf_output_put(handle, abi); | |
6655 | ||
6656 | if (abi) { | |
6657 | u64 mask = event->attr.sample_regs_user; | |
6658 | perf_output_sample_regs(handle, | |
6659 | data->regs_user.regs, | |
6660 | mask); | |
6661 | } | |
6662 | } | |
c5ebcedb | 6663 | |
a5cdd40c | 6664 | if (sample_type & PERF_SAMPLE_STACK_USER) { |
c5ebcedb JO |
6665 | perf_output_sample_ustack(handle, |
6666 | data->stack_user_size, | |
6667 | data->regs_user.regs); | |
a5cdd40c | 6668 | } |
c3feedf2 AK |
6669 | |
6670 | if (sample_type & PERF_SAMPLE_WEIGHT) | |
6671 | perf_output_put(handle, data->weight); | |
d6be9ad6 SE |
6672 | |
6673 | if (sample_type & PERF_SAMPLE_DATA_SRC) | |
6674 | perf_output_put(handle, data->data_src.val); | |
a5cdd40c | 6675 | |
fdfbbd07 AK |
6676 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
6677 | perf_output_put(handle, data->txn); | |
6678 | ||
60e2364e SE |
6679 | if (sample_type & PERF_SAMPLE_REGS_INTR) { |
6680 | u64 abi = data->regs_intr.abi; | |
6681 | /* | |
6682 | * If there are no regs to dump, notice it through | |
6683 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
6684 | */ | |
6685 | perf_output_put(handle, abi); | |
6686 | ||
6687 | if (abi) { | |
6688 | u64 mask = event->attr.sample_regs_intr; | |
6689 | ||
6690 | perf_output_sample_regs(handle, | |
6691 | data->regs_intr.regs, | |
6692 | mask); | |
6693 | } | |
6694 | } | |
6695 | ||
fc7ce9c7 KL |
6696 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) |
6697 | perf_output_put(handle, data->phys_addr); | |
6698 | ||
a4faf00d AS |
6699 | if (sample_type & PERF_SAMPLE_AUX) { |
6700 | perf_output_put(handle, data->aux_size); | |
6701 | ||
6702 | if (data->aux_size) | |
6703 | perf_aux_sample_output(event, handle, data); | |
6704 | } | |
6705 | ||
a5cdd40c PZ |
6706 | if (!event->attr.watermark) { |
6707 | int wakeup_events = event->attr.wakeup_events; | |
6708 | ||
6709 | if (wakeup_events) { | |
56de4e8f | 6710 | struct perf_buffer *rb = handle->rb; |
a5cdd40c PZ |
6711 | int events = local_inc_return(&rb->events); |
6712 | ||
6713 | if (events >= wakeup_events) { | |
6714 | local_sub(wakeup_events, &rb->events); | |
6715 | local_inc(&rb->wakeup); | |
6716 | } | |
6717 | } | |
6718 | } | |
5622f295 MM |
6719 | } |
6720 | ||
fc7ce9c7 KL |
6721 | static u64 perf_virt_to_phys(u64 virt) |
6722 | { | |
6723 | u64 phys_addr = 0; | |
6724 | struct page *p = NULL; | |
6725 | ||
6726 | if (!virt) | |
6727 | return 0; | |
6728 | ||
6729 | if (virt >= TASK_SIZE) { | |
6730 | /* If it's vmalloc()d memory, leave phys_addr as 0 */ | |
6731 | if (virt_addr_valid((void *)(uintptr_t)virt) && | |
6732 | !(virt >= VMALLOC_START && virt < VMALLOC_END)) | |
6733 | phys_addr = (u64)virt_to_phys((void *)(uintptr_t)virt); | |
6734 | } else { | |
6735 | /* | |
6736 | * Walking the pages tables for user address. | |
6737 | * Interrupts are disabled, so it prevents any tear down | |
6738 | * of the page tables. | |
6739 | * Try IRQ-safe __get_user_pages_fast first. | |
6740 | * If failed, leave phys_addr as 0. | |
6741 | */ | |
6742 | if ((current->mm != NULL) && | |
6743 | (__get_user_pages_fast(virt, 1, 0, &p) == 1)) | |
6744 | phys_addr = page_to_phys(p) + virt % PAGE_SIZE; | |
6745 | ||
6746 | if (p) | |
6747 | put_page(p); | |
6748 | } | |
6749 | ||
6750 | return phys_addr; | |
6751 | } | |
6752 | ||
99e818cc JO |
6753 | static struct perf_callchain_entry __empty_callchain = { .nr = 0, }; |
6754 | ||
6cbc304f | 6755 | struct perf_callchain_entry * |
8cf7e0e2 JO |
6756 | perf_callchain(struct perf_event *event, struct pt_regs *regs) |
6757 | { | |
6758 | bool kernel = !event->attr.exclude_callchain_kernel; | |
6759 | bool user = !event->attr.exclude_callchain_user; | |
6760 | /* Disallow cross-task user callchains. */ | |
6761 | bool crosstask = event->ctx->task && event->ctx->task != current; | |
6762 | const u32 max_stack = event->attr.sample_max_stack; | |
99e818cc | 6763 | struct perf_callchain_entry *callchain; |
8cf7e0e2 JO |
6764 | |
6765 | if (!kernel && !user) | |
99e818cc | 6766 | return &__empty_callchain; |
8cf7e0e2 | 6767 | |
99e818cc JO |
6768 | callchain = get_perf_callchain(regs, 0, kernel, user, |
6769 | max_stack, crosstask, true); | |
6770 | return callchain ?: &__empty_callchain; | |
8cf7e0e2 JO |
6771 | } |
6772 | ||
5622f295 MM |
6773 | void perf_prepare_sample(struct perf_event_header *header, |
6774 | struct perf_sample_data *data, | |
cdd6c482 | 6775 | struct perf_event *event, |
5622f295 | 6776 | struct pt_regs *regs) |
7b732a75 | 6777 | { |
cdd6c482 | 6778 | u64 sample_type = event->attr.sample_type; |
7b732a75 | 6779 | |
cdd6c482 | 6780 | header->type = PERF_RECORD_SAMPLE; |
c320c7b7 | 6781 | header->size = sizeof(*header) + event->header_size; |
5622f295 MM |
6782 | |
6783 | header->misc = 0; | |
6784 | header->misc |= perf_misc_flags(regs); | |
6fab0192 | 6785 | |
c980d109 | 6786 | __perf_event_header__init_id(header, data, event); |
6844c09d | 6787 | |
c320c7b7 | 6788 | if (sample_type & PERF_SAMPLE_IP) |
5622f295 MM |
6789 | data->ip = perf_instruction_pointer(regs); |
6790 | ||
b23f3325 | 6791 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { |
5622f295 | 6792 | int size = 1; |
394ee076 | 6793 | |
6cbc304f PZ |
6794 | if (!(sample_type & __PERF_SAMPLE_CALLCHAIN_EARLY)) |
6795 | data->callchain = perf_callchain(event, regs); | |
6796 | ||
99e818cc | 6797 | size += data->callchain->nr; |
5622f295 MM |
6798 | |
6799 | header->size += size * sizeof(u64); | |
394ee076 PZ |
6800 | } |
6801 | ||
3a43ce68 | 6802 | if (sample_type & PERF_SAMPLE_RAW) { |
7e3f977e DB |
6803 | struct perf_raw_record *raw = data->raw; |
6804 | int size; | |
6805 | ||
6806 | if (raw) { | |
6807 | struct perf_raw_frag *frag = &raw->frag; | |
6808 | u32 sum = 0; | |
6809 | ||
6810 | do { | |
6811 | sum += frag->size; | |
6812 | if (perf_raw_frag_last(frag)) | |
6813 | break; | |
6814 | frag = frag->next; | |
6815 | } while (1); | |
6816 | ||
6817 | size = round_up(sum + sizeof(u32), sizeof(u64)); | |
6818 | raw->size = size - sizeof(u32); | |
6819 | frag->pad = raw->size - sum; | |
6820 | } else { | |
6821 | size = sizeof(u64); | |
6822 | } | |
a044560c | 6823 | |
7e3f977e | 6824 | header->size += size; |
7f453c24 | 6825 | } |
bce38cd5 SE |
6826 | |
6827 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { | |
6828 | int size = sizeof(u64); /* nr */ | |
6829 | if (data->br_stack) { | |
bbfd5e4f KL |
6830 | if (perf_sample_save_hw_index(event)) |
6831 | size += sizeof(u64); | |
6832 | ||
bce38cd5 SE |
6833 | size += data->br_stack->nr |
6834 | * sizeof(struct perf_branch_entry); | |
6835 | } | |
6836 | header->size += size; | |
6837 | } | |
4018994f | 6838 | |
2565711f | 6839 | if (sample_type & (PERF_SAMPLE_REGS_USER | PERF_SAMPLE_STACK_USER)) |
88a7c26a AL |
6840 | perf_sample_regs_user(&data->regs_user, regs, |
6841 | &data->regs_user_copy); | |
2565711f | 6842 | |
4018994f JO |
6843 | if (sample_type & PERF_SAMPLE_REGS_USER) { |
6844 | /* regs dump ABI info */ | |
6845 | int size = sizeof(u64); | |
6846 | ||
4018994f JO |
6847 | if (data->regs_user.regs) { |
6848 | u64 mask = event->attr.sample_regs_user; | |
6849 | size += hweight64(mask) * sizeof(u64); | |
6850 | } | |
6851 | ||
6852 | header->size += size; | |
6853 | } | |
c5ebcedb JO |
6854 | |
6855 | if (sample_type & PERF_SAMPLE_STACK_USER) { | |
6856 | /* | |
9f014e3a | 6857 | * Either we need PERF_SAMPLE_STACK_USER bit to be always |
c5ebcedb JO |
6858 | * processed as the last one or have additional check added |
6859 | * in case new sample type is added, because we could eat | |
6860 | * up the rest of the sample size. | |
6861 | */ | |
c5ebcedb JO |
6862 | u16 stack_size = event->attr.sample_stack_user; |
6863 | u16 size = sizeof(u64); | |
6864 | ||
c5ebcedb | 6865 | stack_size = perf_sample_ustack_size(stack_size, header->size, |
2565711f | 6866 | data->regs_user.regs); |
c5ebcedb JO |
6867 | |
6868 | /* | |
6869 | * If there is something to dump, add space for the dump | |
6870 | * itself and for the field that tells the dynamic size, | |
6871 | * which is how many have been actually dumped. | |
6872 | */ | |
6873 | if (stack_size) | |
6874 | size += sizeof(u64) + stack_size; | |
6875 | ||
6876 | data->stack_user_size = stack_size; | |
6877 | header->size += size; | |
6878 | } | |
60e2364e SE |
6879 | |
6880 | if (sample_type & PERF_SAMPLE_REGS_INTR) { | |
6881 | /* regs dump ABI info */ | |
6882 | int size = sizeof(u64); | |
6883 | ||
6884 | perf_sample_regs_intr(&data->regs_intr, regs); | |
6885 | ||
6886 | if (data->regs_intr.regs) { | |
6887 | u64 mask = event->attr.sample_regs_intr; | |
6888 | ||
6889 | size += hweight64(mask) * sizeof(u64); | |
6890 | } | |
6891 | ||
6892 | header->size += size; | |
6893 | } | |
fc7ce9c7 KL |
6894 | |
6895 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) | |
6896 | data->phys_addr = perf_virt_to_phys(data->addr); | |
a4faf00d AS |
6897 | |
6898 | if (sample_type & PERF_SAMPLE_AUX) { | |
6899 | u64 size; | |
6900 | ||
6901 | header->size += sizeof(u64); /* size */ | |
6902 | ||
6903 | /* | |
6904 | * Given the 16bit nature of header::size, an AUX sample can | |
6905 | * easily overflow it, what with all the preceding sample bits. | |
6906 | * Make sure this doesn't happen by using up to U16_MAX bytes | |
6907 | * per sample in total (rounded down to 8 byte boundary). | |
6908 | */ | |
6909 | size = min_t(size_t, U16_MAX - header->size, | |
6910 | event->attr.aux_sample_size); | |
6911 | size = rounddown(size, 8); | |
6912 | size = perf_prepare_sample_aux(event, data, size); | |
6913 | ||
6914 | WARN_ON_ONCE(size + header->size > U16_MAX); | |
6915 | header->size += size; | |
6916 | } | |
6917 | /* | |
6918 | * If you're adding more sample types here, you likely need to do | |
6919 | * something about the overflowing header::size, like repurpose the | |
6920 | * lowest 3 bits of size, which should be always zero at the moment. | |
6921 | * This raises a more important question, do we really need 512k sized | |
6922 | * samples and why, so good argumentation is in order for whatever you | |
6923 | * do here next. | |
6924 | */ | |
6925 | WARN_ON_ONCE(header->size & 7); | |
5622f295 | 6926 | } |
7f453c24 | 6927 | |
56201969 | 6928 | static __always_inline int |
9ecda41a WN |
6929 | __perf_event_output(struct perf_event *event, |
6930 | struct perf_sample_data *data, | |
6931 | struct pt_regs *regs, | |
6932 | int (*output_begin)(struct perf_output_handle *, | |
6933 | struct perf_event *, | |
6934 | unsigned int)) | |
5622f295 MM |
6935 | { |
6936 | struct perf_output_handle handle; | |
6937 | struct perf_event_header header; | |
56201969 | 6938 | int err; |
689802b2 | 6939 | |
927c7a9e FW |
6940 | /* protect the callchain buffers */ |
6941 | rcu_read_lock(); | |
6942 | ||
cdd6c482 | 6943 | perf_prepare_sample(&header, data, event, regs); |
5c148194 | 6944 | |
56201969 ACM |
6945 | err = output_begin(&handle, event, header.size); |
6946 | if (err) | |
927c7a9e | 6947 | goto exit; |
0322cd6e | 6948 | |
cdd6c482 | 6949 | perf_output_sample(&handle, &header, data, event); |
f413cdb8 | 6950 | |
8a057d84 | 6951 | perf_output_end(&handle); |
927c7a9e FW |
6952 | |
6953 | exit: | |
6954 | rcu_read_unlock(); | |
56201969 | 6955 | return err; |
0322cd6e PZ |
6956 | } |
6957 | ||
9ecda41a WN |
6958 | void |
6959 | perf_event_output_forward(struct perf_event *event, | |
6960 | struct perf_sample_data *data, | |
6961 | struct pt_regs *regs) | |
6962 | { | |
6963 | __perf_event_output(event, data, regs, perf_output_begin_forward); | |
6964 | } | |
6965 | ||
6966 | void | |
6967 | perf_event_output_backward(struct perf_event *event, | |
6968 | struct perf_sample_data *data, | |
6969 | struct pt_regs *regs) | |
6970 | { | |
6971 | __perf_event_output(event, data, regs, perf_output_begin_backward); | |
6972 | } | |
6973 | ||
56201969 | 6974 | int |
9ecda41a WN |
6975 | perf_event_output(struct perf_event *event, |
6976 | struct perf_sample_data *data, | |
6977 | struct pt_regs *regs) | |
6978 | { | |
56201969 | 6979 | return __perf_event_output(event, data, regs, perf_output_begin); |
9ecda41a WN |
6980 | } |
6981 | ||
38b200d6 | 6982 | /* |
cdd6c482 | 6983 | * read event_id |
38b200d6 PZ |
6984 | */ |
6985 | ||
6986 | struct perf_read_event { | |
6987 | struct perf_event_header header; | |
6988 | ||
6989 | u32 pid; | |
6990 | u32 tid; | |
38b200d6 PZ |
6991 | }; |
6992 | ||
6993 | static void | |
cdd6c482 | 6994 | perf_event_read_event(struct perf_event *event, |
38b200d6 PZ |
6995 | struct task_struct *task) |
6996 | { | |
6997 | struct perf_output_handle handle; | |
c980d109 | 6998 | struct perf_sample_data sample; |
dfc65094 | 6999 | struct perf_read_event read_event = { |
38b200d6 | 7000 | .header = { |
cdd6c482 | 7001 | .type = PERF_RECORD_READ, |
38b200d6 | 7002 | .misc = 0, |
c320c7b7 | 7003 | .size = sizeof(read_event) + event->read_size, |
38b200d6 | 7004 | }, |
cdd6c482 IM |
7005 | .pid = perf_event_pid(event, task), |
7006 | .tid = perf_event_tid(event, task), | |
38b200d6 | 7007 | }; |
3dab77fb | 7008 | int ret; |
38b200d6 | 7009 | |
c980d109 | 7010 | perf_event_header__init_id(&read_event.header, &sample, event); |
a7ac67ea | 7011 | ret = perf_output_begin(&handle, event, read_event.header.size); |
38b200d6 PZ |
7012 | if (ret) |
7013 | return; | |
7014 | ||
dfc65094 | 7015 | perf_output_put(&handle, read_event); |
cdd6c482 | 7016 | perf_output_read(&handle, event); |
c980d109 | 7017 | perf_event__output_id_sample(event, &handle, &sample); |
3dab77fb | 7018 | |
38b200d6 PZ |
7019 | perf_output_end(&handle); |
7020 | } | |
7021 | ||
aab5b71e | 7022 | typedef void (perf_iterate_f)(struct perf_event *event, void *data); |
52d857a8 JO |
7023 | |
7024 | static void | |
aab5b71e PZ |
7025 | perf_iterate_ctx(struct perf_event_context *ctx, |
7026 | perf_iterate_f output, | |
b73e4fef | 7027 | void *data, bool all) |
52d857a8 JO |
7028 | { |
7029 | struct perf_event *event; | |
7030 | ||
7031 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
b73e4fef AS |
7032 | if (!all) { |
7033 | if (event->state < PERF_EVENT_STATE_INACTIVE) | |
7034 | continue; | |
7035 | if (!event_filter_match(event)) | |
7036 | continue; | |
7037 | } | |
7038 | ||
67516844 | 7039 | output(event, data); |
52d857a8 JO |
7040 | } |
7041 | } | |
7042 | ||
aab5b71e | 7043 | static void perf_iterate_sb_cpu(perf_iterate_f output, void *data) |
f2fb6bef KL |
7044 | { |
7045 | struct pmu_event_list *pel = this_cpu_ptr(&pmu_sb_events); | |
7046 | struct perf_event *event; | |
7047 | ||
7048 | list_for_each_entry_rcu(event, &pel->list, sb_list) { | |
0b8f1e2e PZ |
7049 | /* |
7050 | * Skip events that are not fully formed yet; ensure that | |
7051 | * if we observe event->ctx, both event and ctx will be | |
7052 | * complete enough. See perf_install_in_context(). | |
7053 | */ | |
7054 | if (!smp_load_acquire(&event->ctx)) | |
7055 | continue; | |
7056 | ||
f2fb6bef KL |
7057 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
7058 | continue; | |
7059 | if (!event_filter_match(event)) | |
7060 | continue; | |
7061 | output(event, data); | |
7062 | } | |
7063 | } | |
7064 | ||
aab5b71e PZ |
7065 | /* |
7066 | * Iterate all events that need to receive side-band events. | |
7067 | * | |
7068 | * For new callers; ensure that account_pmu_sb_event() includes | |
7069 | * your event, otherwise it might not get delivered. | |
7070 | */ | |
52d857a8 | 7071 | static void |
aab5b71e | 7072 | perf_iterate_sb(perf_iterate_f output, void *data, |
52d857a8 JO |
7073 | struct perf_event_context *task_ctx) |
7074 | { | |
52d857a8 | 7075 | struct perf_event_context *ctx; |
52d857a8 JO |
7076 | int ctxn; |
7077 | ||
aab5b71e PZ |
7078 | rcu_read_lock(); |
7079 | preempt_disable(); | |
7080 | ||
4e93ad60 | 7081 | /* |
aab5b71e PZ |
7082 | * If we have task_ctx != NULL we only notify the task context itself. |
7083 | * The task_ctx is set only for EXIT events before releasing task | |
4e93ad60 JO |
7084 | * context. |
7085 | */ | |
7086 | if (task_ctx) { | |
aab5b71e PZ |
7087 | perf_iterate_ctx(task_ctx, output, data, false); |
7088 | goto done; | |
4e93ad60 JO |
7089 | } |
7090 | ||
aab5b71e | 7091 | perf_iterate_sb_cpu(output, data); |
f2fb6bef KL |
7092 | |
7093 | for_each_task_context_nr(ctxn) { | |
52d857a8 JO |
7094 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); |
7095 | if (ctx) | |
aab5b71e | 7096 | perf_iterate_ctx(ctx, output, data, false); |
52d857a8 | 7097 | } |
aab5b71e | 7098 | done: |
f2fb6bef | 7099 | preempt_enable(); |
52d857a8 | 7100 | rcu_read_unlock(); |
95ff4ca2 AS |
7101 | } |
7102 | ||
375637bc AS |
7103 | /* |
7104 | * Clear all file-based filters at exec, they'll have to be | |
7105 | * re-instated when/if these objects are mmapped again. | |
7106 | */ | |
7107 | static void perf_event_addr_filters_exec(struct perf_event *event, void *data) | |
7108 | { | |
7109 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
7110 | struct perf_addr_filter *filter; | |
7111 | unsigned int restart = 0, count = 0; | |
7112 | unsigned long flags; | |
7113 | ||
7114 | if (!has_addr_filter(event)) | |
7115 | return; | |
7116 | ||
7117 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
7118 | list_for_each_entry(filter, &ifh->list, entry) { | |
9511bce9 | 7119 | if (filter->path.dentry) { |
c60f83b8 AS |
7120 | event->addr_filter_ranges[count].start = 0; |
7121 | event->addr_filter_ranges[count].size = 0; | |
375637bc AS |
7122 | restart++; |
7123 | } | |
7124 | ||
7125 | count++; | |
7126 | } | |
7127 | ||
7128 | if (restart) | |
7129 | event->addr_filters_gen++; | |
7130 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
7131 | ||
7132 | if (restart) | |
767ae086 | 7133 | perf_event_stop(event, 1); |
375637bc AS |
7134 | } |
7135 | ||
7136 | void perf_event_exec(void) | |
7137 | { | |
7138 | struct perf_event_context *ctx; | |
7139 | int ctxn; | |
7140 | ||
7141 | rcu_read_lock(); | |
7142 | for_each_task_context_nr(ctxn) { | |
7143 | ctx = current->perf_event_ctxp[ctxn]; | |
7144 | if (!ctx) | |
7145 | continue; | |
7146 | ||
7147 | perf_event_enable_on_exec(ctxn); | |
7148 | ||
aab5b71e | 7149 | perf_iterate_ctx(ctx, perf_event_addr_filters_exec, NULL, |
375637bc AS |
7150 | true); |
7151 | } | |
7152 | rcu_read_unlock(); | |
7153 | } | |
7154 | ||
95ff4ca2 | 7155 | struct remote_output { |
56de4e8f | 7156 | struct perf_buffer *rb; |
95ff4ca2 AS |
7157 | int err; |
7158 | }; | |
7159 | ||
7160 | static void __perf_event_output_stop(struct perf_event *event, void *data) | |
7161 | { | |
7162 | struct perf_event *parent = event->parent; | |
7163 | struct remote_output *ro = data; | |
56de4e8f | 7164 | struct perf_buffer *rb = ro->rb; |
375637bc AS |
7165 | struct stop_event_data sd = { |
7166 | .event = event, | |
7167 | }; | |
95ff4ca2 AS |
7168 | |
7169 | if (!has_aux(event)) | |
7170 | return; | |
7171 | ||
7172 | if (!parent) | |
7173 | parent = event; | |
7174 | ||
7175 | /* | |
7176 | * In case of inheritance, it will be the parent that links to the | |
767ae086 AS |
7177 | * ring-buffer, but it will be the child that's actually using it. |
7178 | * | |
7179 | * We are using event::rb to determine if the event should be stopped, | |
7180 | * however this may race with ring_buffer_attach() (through set_output), | |
7181 | * which will make us skip the event that actually needs to be stopped. | |
7182 | * So ring_buffer_attach() has to stop an aux event before re-assigning | |
7183 | * its rb pointer. | |
95ff4ca2 AS |
7184 | */ |
7185 | if (rcu_dereference(parent->rb) == rb) | |
375637bc | 7186 | ro->err = __perf_event_stop(&sd); |
95ff4ca2 AS |
7187 | } |
7188 | ||
7189 | static int __perf_pmu_output_stop(void *info) | |
7190 | { | |
7191 | struct perf_event *event = info; | |
f3a519e4 | 7192 | struct pmu *pmu = event->ctx->pmu; |
8b6a3fe8 | 7193 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
95ff4ca2 AS |
7194 | struct remote_output ro = { |
7195 | .rb = event->rb, | |
7196 | }; | |
7197 | ||
7198 | rcu_read_lock(); | |
aab5b71e | 7199 | perf_iterate_ctx(&cpuctx->ctx, __perf_event_output_stop, &ro, false); |
95ff4ca2 | 7200 | if (cpuctx->task_ctx) |
aab5b71e | 7201 | perf_iterate_ctx(cpuctx->task_ctx, __perf_event_output_stop, |
b73e4fef | 7202 | &ro, false); |
95ff4ca2 AS |
7203 | rcu_read_unlock(); |
7204 | ||
7205 | return ro.err; | |
7206 | } | |
7207 | ||
7208 | static void perf_pmu_output_stop(struct perf_event *event) | |
7209 | { | |
7210 | struct perf_event *iter; | |
7211 | int err, cpu; | |
7212 | ||
7213 | restart: | |
7214 | rcu_read_lock(); | |
7215 | list_for_each_entry_rcu(iter, &event->rb->event_list, rb_entry) { | |
7216 | /* | |
7217 | * For per-CPU events, we need to make sure that neither they | |
7218 | * nor their children are running; for cpu==-1 events it's | |
7219 | * sufficient to stop the event itself if it's active, since | |
7220 | * it can't have children. | |
7221 | */ | |
7222 | cpu = iter->cpu; | |
7223 | if (cpu == -1) | |
7224 | cpu = READ_ONCE(iter->oncpu); | |
7225 | ||
7226 | if (cpu == -1) | |
7227 | continue; | |
7228 | ||
7229 | err = cpu_function_call(cpu, __perf_pmu_output_stop, event); | |
7230 | if (err == -EAGAIN) { | |
7231 | rcu_read_unlock(); | |
7232 | goto restart; | |
7233 | } | |
7234 | } | |
7235 | rcu_read_unlock(); | |
52d857a8 JO |
7236 | } |
7237 | ||
60313ebe | 7238 | /* |
9f498cc5 PZ |
7239 | * task tracking -- fork/exit |
7240 | * | |
13d7a241 | 7241 | * enabled by: attr.comm | attr.mmap | attr.mmap2 | attr.mmap_data | attr.task |
60313ebe PZ |
7242 | */ |
7243 | ||
9f498cc5 | 7244 | struct perf_task_event { |
3a80b4a3 | 7245 | struct task_struct *task; |
cdd6c482 | 7246 | struct perf_event_context *task_ctx; |
60313ebe PZ |
7247 | |
7248 | struct { | |
7249 | struct perf_event_header header; | |
7250 | ||
7251 | u32 pid; | |
7252 | u32 ppid; | |
9f498cc5 PZ |
7253 | u32 tid; |
7254 | u32 ptid; | |
393b2ad8 | 7255 | u64 time; |
cdd6c482 | 7256 | } event_id; |
60313ebe PZ |
7257 | }; |
7258 | ||
67516844 JO |
7259 | static int perf_event_task_match(struct perf_event *event) |
7260 | { | |
13d7a241 SE |
7261 | return event->attr.comm || event->attr.mmap || |
7262 | event->attr.mmap2 || event->attr.mmap_data || | |
7263 | event->attr.task; | |
67516844 JO |
7264 | } |
7265 | ||
cdd6c482 | 7266 | static void perf_event_task_output(struct perf_event *event, |
52d857a8 | 7267 | void *data) |
60313ebe | 7268 | { |
52d857a8 | 7269 | struct perf_task_event *task_event = data; |
60313ebe | 7270 | struct perf_output_handle handle; |
c980d109 | 7271 | struct perf_sample_data sample; |
9f498cc5 | 7272 | struct task_struct *task = task_event->task; |
c980d109 | 7273 | int ret, size = task_event->event_id.header.size; |
8bb39f9a | 7274 | |
67516844 JO |
7275 | if (!perf_event_task_match(event)) |
7276 | return; | |
7277 | ||
c980d109 | 7278 | perf_event_header__init_id(&task_event->event_id.header, &sample, event); |
60313ebe | 7279 | |
c980d109 | 7280 | ret = perf_output_begin(&handle, event, |
a7ac67ea | 7281 | task_event->event_id.header.size); |
ef60777c | 7282 | if (ret) |
c980d109 | 7283 | goto out; |
60313ebe | 7284 | |
cdd6c482 IM |
7285 | task_event->event_id.pid = perf_event_pid(event, task); |
7286 | task_event->event_id.ppid = perf_event_pid(event, current); | |
60313ebe | 7287 | |
cdd6c482 IM |
7288 | task_event->event_id.tid = perf_event_tid(event, task); |
7289 | task_event->event_id.ptid = perf_event_tid(event, current); | |
9f498cc5 | 7290 | |
34f43927 PZ |
7291 | task_event->event_id.time = perf_event_clock(event); |
7292 | ||
cdd6c482 | 7293 | perf_output_put(&handle, task_event->event_id); |
393b2ad8 | 7294 | |
c980d109 ACM |
7295 | perf_event__output_id_sample(event, &handle, &sample); |
7296 | ||
60313ebe | 7297 | perf_output_end(&handle); |
c980d109 ACM |
7298 | out: |
7299 | task_event->event_id.header.size = size; | |
60313ebe PZ |
7300 | } |
7301 | ||
cdd6c482 IM |
7302 | static void perf_event_task(struct task_struct *task, |
7303 | struct perf_event_context *task_ctx, | |
3a80b4a3 | 7304 | int new) |
60313ebe | 7305 | { |
9f498cc5 | 7306 | struct perf_task_event task_event; |
60313ebe | 7307 | |
cdd6c482 IM |
7308 | if (!atomic_read(&nr_comm_events) && |
7309 | !atomic_read(&nr_mmap_events) && | |
7310 | !atomic_read(&nr_task_events)) | |
60313ebe PZ |
7311 | return; |
7312 | ||
9f498cc5 | 7313 | task_event = (struct perf_task_event){ |
3a80b4a3 PZ |
7314 | .task = task, |
7315 | .task_ctx = task_ctx, | |
cdd6c482 | 7316 | .event_id = { |
60313ebe | 7317 | .header = { |
cdd6c482 | 7318 | .type = new ? PERF_RECORD_FORK : PERF_RECORD_EXIT, |
573402db | 7319 | .misc = 0, |
cdd6c482 | 7320 | .size = sizeof(task_event.event_id), |
60313ebe | 7321 | }, |
573402db PZ |
7322 | /* .pid */ |
7323 | /* .ppid */ | |
9f498cc5 PZ |
7324 | /* .tid */ |
7325 | /* .ptid */ | |
34f43927 | 7326 | /* .time */ |
60313ebe PZ |
7327 | }, |
7328 | }; | |
7329 | ||
aab5b71e | 7330 | perf_iterate_sb(perf_event_task_output, |
52d857a8 JO |
7331 | &task_event, |
7332 | task_ctx); | |
9f498cc5 PZ |
7333 | } |
7334 | ||
cdd6c482 | 7335 | void perf_event_fork(struct task_struct *task) |
9f498cc5 | 7336 | { |
cdd6c482 | 7337 | perf_event_task(task, NULL, 1); |
e4222673 | 7338 | perf_event_namespaces(task); |
60313ebe PZ |
7339 | } |
7340 | ||
8d1b2d93 PZ |
7341 | /* |
7342 | * comm tracking | |
7343 | */ | |
7344 | ||
7345 | struct perf_comm_event { | |
22a4f650 IM |
7346 | struct task_struct *task; |
7347 | char *comm; | |
8d1b2d93 PZ |
7348 | int comm_size; |
7349 | ||
7350 | struct { | |
7351 | struct perf_event_header header; | |
7352 | ||
7353 | u32 pid; | |
7354 | u32 tid; | |
cdd6c482 | 7355 | } event_id; |
8d1b2d93 PZ |
7356 | }; |
7357 | ||
67516844 JO |
7358 | static int perf_event_comm_match(struct perf_event *event) |
7359 | { | |
7360 | return event->attr.comm; | |
7361 | } | |
7362 | ||
cdd6c482 | 7363 | static void perf_event_comm_output(struct perf_event *event, |
52d857a8 | 7364 | void *data) |
8d1b2d93 | 7365 | { |
52d857a8 | 7366 | struct perf_comm_event *comm_event = data; |
8d1b2d93 | 7367 | struct perf_output_handle handle; |
c980d109 | 7368 | struct perf_sample_data sample; |
cdd6c482 | 7369 | int size = comm_event->event_id.header.size; |
c980d109 ACM |
7370 | int ret; |
7371 | ||
67516844 JO |
7372 | if (!perf_event_comm_match(event)) |
7373 | return; | |
7374 | ||
c980d109 ACM |
7375 | perf_event_header__init_id(&comm_event->event_id.header, &sample, event); |
7376 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 7377 | comm_event->event_id.header.size); |
8d1b2d93 PZ |
7378 | |
7379 | if (ret) | |
c980d109 | 7380 | goto out; |
8d1b2d93 | 7381 | |
cdd6c482 IM |
7382 | comm_event->event_id.pid = perf_event_pid(event, comm_event->task); |
7383 | comm_event->event_id.tid = perf_event_tid(event, comm_event->task); | |
709e50cf | 7384 | |
cdd6c482 | 7385 | perf_output_put(&handle, comm_event->event_id); |
76369139 | 7386 | __output_copy(&handle, comm_event->comm, |
8d1b2d93 | 7387 | comm_event->comm_size); |
c980d109 ACM |
7388 | |
7389 | perf_event__output_id_sample(event, &handle, &sample); | |
7390 | ||
8d1b2d93 | 7391 | perf_output_end(&handle); |
c980d109 ACM |
7392 | out: |
7393 | comm_event->event_id.header.size = size; | |
8d1b2d93 PZ |
7394 | } |
7395 | ||
cdd6c482 | 7396 | static void perf_event_comm_event(struct perf_comm_event *comm_event) |
8d1b2d93 | 7397 | { |
413ee3b4 | 7398 | char comm[TASK_COMM_LEN]; |
8d1b2d93 | 7399 | unsigned int size; |
8d1b2d93 | 7400 | |
413ee3b4 | 7401 | memset(comm, 0, sizeof(comm)); |
96b02d78 | 7402 | strlcpy(comm, comm_event->task->comm, sizeof(comm)); |
888fcee0 | 7403 | size = ALIGN(strlen(comm)+1, sizeof(u64)); |
8d1b2d93 PZ |
7404 | |
7405 | comm_event->comm = comm; | |
7406 | comm_event->comm_size = size; | |
7407 | ||
cdd6c482 | 7408 | comm_event->event_id.header.size = sizeof(comm_event->event_id) + size; |
8dc85d54 | 7409 | |
aab5b71e | 7410 | perf_iterate_sb(perf_event_comm_output, |
52d857a8 JO |
7411 | comm_event, |
7412 | NULL); | |
8d1b2d93 PZ |
7413 | } |
7414 | ||
82b89778 | 7415 | void perf_event_comm(struct task_struct *task, bool exec) |
8d1b2d93 | 7416 | { |
9ee318a7 PZ |
7417 | struct perf_comm_event comm_event; |
7418 | ||
cdd6c482 | 7419 | if (!atomic_read(&nr_comm_events)) |
9ee318a7 | 7420 | return; |
a63eaf34 | 7421 | |
9ee318a7 | 7422 | comm_event = (struct perf_comm_event){ |
8d1b2d93 | 7423 | .task = task, |
573402db PZ |
7424 | /* .comm */ |
7425 | /* .comm_size */ | |
cdd6c482 | 7426 | .event_id = { |
573402db | 7427 | .header = { |
cdd6c482 | 7428 | .type = PERF_RECORD_COMM, |
82b89778 | 7429 | .misc = exec ? PERF_RECORD_MISC_COMM_EXEC : 0, |
573402db PZ |
7430 | /* .size */ |
7431 | }, | |
7432 | /* .pid */ | |
7433 | /* .tid */ | |
8d1b2d93 PZ |
7434 | }, |
7435 | }; | |
7436 | ||
cdd6c482 | 7437 | perf_event_comm_event(&comm_event); |
8d1b2d93 PZ |
7438 | } |
7439 | ||
e4222673 HB |
7440 | /* |
7441 | * namespaces tracking | |
7442 | */ | |
7443 | ||
7444 | struct perf_namespaces_event { | |
7445 | struct task_struct *task; | |
7446 | ||
7447 | struct { | |
7448 | struct perf_event_header header; | |
7449 | ||
7450 | u32 pid; | |
7451 | u32 tid; | |
7452 | u64 nr_namespaces; | |
7453 | struct perf_ns_link_info link_info[NR_NAMESPACES]; | |
7454 | } event_id; | |
7455 | }; | |
7456 | ||
7457 | static int perf_event_namespaces_match(struct perf_event *event) | |
7458 | { | |
7459 | return event->attr.namespaces; | |
7460 | } | |
7461 | ||
7462 | static void perf_event_namespaces_output(struct perf_event *event, | |
7463 | void *data) | |
7464 | { | |
7465 | struct perf_namespaces_event *namespaces_event = data; | |
7466 | struct perf_output_handle handle; | |
7467 | struct perf_sample_data sample; | |
34900ec5 | 7468 | u16 header_size = namespaces_event->event_id.header.size; |
e4222673 HB |
7469 | int ret; |
7470 | ||
7471 | if (!perf_event_namespaces_match(event)) | |
7472 | return; | |
7473 | ||
7474 | perf_event_header__init_id(&namespaces_event->event_id.header, | |
7475 | &sample, event); | |
7476 | ret = perf_output_begin(&handle, event, | |
7477 | namespaces_event->event_id.header.size); | |
7478 | if (ret) | |
34900ec5 | 7479 | goto out; |
e4222673 HB |
7480 | |
7481 | namespaces_event->event_id.pid = perf_event_pid(event, | |
7482 | namespaces_event->task); | |
7483 | namespaces_event->event_id.tid = perf_event_tid(event, | |
7484 | namespaces_event->task); | |
7485 | ||
7486 | perf_output_put(&handle, namespaces_event->event_id); | |
7487 | ||
7488 | perf_event__output_id_sample(event, &handle, &sample); | |
7489 | ||
7490 | perf_output_end(&handle); | |
34900ec5 JO |
7491 | out: |
7492 | namespaces_event->event_id.header.size = header_size; | |
e4222673 HB |
7493 | } |
7494 | ||
7495 | static void perf_fill_ns_link_info(struct perf_ns_link_info *ns_link_info, | |
7496 | struct task_struct *task, | |
7497 | const struct proc_ns_operations *ns_ops) | |
7498 | { | |
7499 | struct path ns_path; | |
7500 | struct inode *ns_inode; | |
ce623f89 | 7501 | int error; |
e4222673 HB |
7502 | |
7503 | error = ns_get_path(&ns_path, task, ns_ops); | |
7504 | if (!error) { | |
7505 | ns_inode = ns_path.dentry->d_inode; | |
7506 | ns_link_info->dev = new_encode_dev(ns_inode->i_sb->s_dev); | |
7507 | ns_link_info->ino = ns_inode->i_ino; | |
0e18dd12 | 7508 | path_put(&ns_path); |
e4222673 HB |
7509 | } |
7510 | } | |
7511 | ||
7512 | void perf_event_namespaces(struct task_struct *task) | |
7513 | { | |
7514 | struct perf_namespaces_event namespaces_event; | |
7515 | struct perf_ns_link_info *ns_link_info; | |
7516 | ||
7517 | if (!atomic_read(&nr_namespaces_events)) | |
7518 | return; | |
7519 | ||
7520 | namespaces_event = (struct perf_namespaces_event){ | |
7521 | .task = task, | |
7522 | .event_id = { | |
7523 | .header = { | |
7524 | .type = PERF_RECORD_NAMESPACES, | |
7525 | .misc = 0, | |
7526 | .size = sizeof(namespaces_event.event_id), | |
7527 | }, | |
7528 | /* .pid */ | |
7529 | /* .tid */ | |
7530 | .nr_namespaces = NR_NAMESPACES, | |
7531 | /* .link_info[NR_NAMESPACES] */ | |
7532 | }, | |
7533 | }; | |
7534 | ||
7535 | ns_link_info = namespaces_event.event_id.link_info; | |
7536 | ||
7537 | perf_fill_ns_link_info(&ns_link_info[MNT_NS_INDEX], | |
7538 | task, &mntns_operations); | |
7539 | ||
7540 | #ifdef CONFIG_USER_NS | |
7541 | perf_fill_ns_link_info(&ns_link_info[USER_NS_INDEX], | |
7542 | task, &userns_operations); | |
7543 | #endif | |
7544 | #ifdef CONFIG_NET_NS | |
7545 | perf_fill_ns_link_info(&ns_link_info[NET_NS_INDEX], | |
7546 | task, &netns_operations); | |
7547 | #endif | |
7548 | #ifdef CONFIG_UTS_NS | |
7549 | perf_fill_ns_link_info(&ns_link_info[UTS_NS_INDEX], | |
7550 | task, &utsns_operations); | |
7551 | #endif | |
7552 | #ifdef CONFIG_IPC_NS | |
7553 | perf_fill_ns_link_info(&ns_link_info[IPC_NS_INDEX], | |
7554 | task, &ipcns_operations); | |
7555 | #endif | |
7556 | #ifdef CONFIG_PID_NS | |
7557 | perf_fill_ns_link_info(&ns_link_info[PID_NS_INDEX], | |
7558 | task, &pidns_operations); | |
7559 | #endif | |
7560 | #ifdef CONFIG_CGROUPS | |
7561 | perf_fill_ns_link_info(&ns_link_info[CGROUP_NS_INDEX], | |
7562 | task, &cgroupns_operations); | |
7563 | #endif | |
7564 | ||
7565 | perf_iterate_sb(perf_event_namespaces_output, | |
7566 | &namespaces_event, | |
7567 | NULL); | |
7568 | } | |
7569 | ||
0a4a9391 PZ |
7570 | /* |
7571 | * mmap tracking | |
7572 | */ | |
7573 | ||
7574 | struct perf_mmap_event { | |
089dd79d PZ |
7575 | struct vm_area_struct *vma; |
7576 | ||
7577 | const char *file_name; | |
7578 | int file_size; | |
13d7a241 SE |
7579 | int maj, min; |
7580 | u64 ino; | |
7581 | u64 ino_generation; | |
f972eb63 | 7582 | u32 prot, flags; |
0a4a9391 PZ |
7583 | |
7584 | struct { | |
7585 | struct perf_event_header header; | |
7586 | ||
7587 | u32 pid; | |
7588 | u32 tid; | |
7589 | u64 start; | |
7590 | u64 len; | |
7591 | u64 pgoff; | |
cdd6c482 | 7592 | } event_id; |
0a4a9391 PZ |
7593 | }; |
7594 | ||
67516844 JO |
7595 | static int perf_event_mmap_match(struct perf_event *event, |
7596 | void *data) | |
7597 | { | |
7598 | struct perf_mmap_event *mmap_event = data; | |
7599 | struct vm_area_struct *vma = mmap_event->vma; | |
7600 | int executable = vma->vm_flags & VM_EXEC; | |
7601 | ||
7602 | return (!executable && event->attr.mmap_data) || | |
13d7a241 | 7603 | (executable && (event->attr.mmap || event->attr.mmap2)); |
67516844 JO |
7604 | } |
7605 | ||
cdd6c482 | 7606 | static void perf_event_mmap_output(struct perf_event *event, |
52d857a8 | 7607 | void *data) |
0a4a9391 | 7608 | { |
52d857a8 | 7609 | struct perf_mmap_event *mmap_event = data; |
0a4a9391 | 7610 | struct perf_output_handle handle; |
c980d109 | 7611 | struct perf_sample_data sample; |
cdd6c482 | 7612 | int size = mmap_event->event_id.header.size; |
d9c1bb2f | 7613 | u32 type = mmap_event->event_id.header.type; |
c980d109 | 7614 | int ret; |
0a4a9391 | 7615 | |
67516844 JO |
7616 | if (!perf_event_mmap_match(event, data)) |
7617 | return; | |
7618 | ||
13d7a241 SE |
7619 | if (event->attr.mmap2) { |
7620 | mmap_event->event_id.header.type = PERF_RECORD_MMAP2; | |
7621 | mmap_event->event_id.header.size += sizeof(mmap_event->maj); | |
7622 | mmap_event->event_id.header.size += sizeof(mmap_event->min); | |
7623 | mmap_event->event_id.header.size += sizeof(mmap_event->ino); | |
d008d525 | 7624 | mmap_event->event_id.header.size += sizeof(mmap_event->ino_generation); |
f972eb63 PZ |
7625 | mmap_event->event_id.header.size += sizeof(mmap_event->prot); |
7626 | mmap_event->event_id.header.size += sizeof(mmap_event->flags); | |
13d7a241 SE |
7627 | } |
7628 | ||
c980d109 ACM |
7629 | perf_event_header__init_id(&mmap_event->event_id.header, &sample, event); |
7630 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 7631 | mmap_event->event_id.header.size); |
0a4a9391 | 7632 | if (ret) |
c980d109 | 7633 | goto out; |
0a4a9391 | 7634 | |
cdd6c482 IM |
7635 | mmap_event->event_id.pid = perf_event_pid(event, current); |
7636 | mmap_event->event_id.tid = perf_event_tid(event, current); | |
709e50cf | 7637 | |
cdd6c482 | 7638 | perf_output_put(&handle, mmap_event->event_id); |
13d7a241 SE |
7639 | |
7640 | if (event->attr.mmap2) { | |
7641 | perf_output_put(&handle, mmap_event->maj); | |
7642 | perf_output_put(&handle, mmap_event->min); | |
7643 | perf_output_put(&handle, mmap_event->ino); | |
7644 | perf_output_put(&handle, mmap_event->ino_generation); | |
f972eb63 PZ |
7645 | perf_output_put(&handle, mmap_event->prot); |
7646 | perf_output_put(&handle, mmap_event->flags); | |
13d7a241 SE |
7647 | } |
7648 | ||
76369139 | 7649 | __output_copy(&handle, mmap_event->file_name, |
0a4a9391 | 7650 | mmap_event->file_size); |
c980d109 ACM |
7651 | |
7652 | perf_event__output_id_sample(event, &handle, &sample); | |
7653 | ||
78d613eb | 7654 | perf_output_end(&handle); |
c980d109 ACM |
7655 | out: |
7656 | mmap_event->event_id.header.size = size; | |
d9c1bb2f | 7657 | mmap_event->event_id.header.type = type; |
0a4a9391 PZ |
7658 | } |
7659 | ||
cdd6c482 | 7660 | static void perf_event_mmap_event(struct perf_mmap_event *mmap_event) |
0a4a9391 | 7661 | { |
089dd79d PZ |
7662 | struct vm_area_struct *vma = mmap_event->vma; |
7663 | struct file *file = vma->vm_file; | |
13d7a241 SE |
7664 | int maj = 0, min = 0; |
7665 | u64 ino = 0, gen = 0; | |
f972eb63 | 7666 | u32 prot = 0, flags = 0; |
0a4a9391 PZ |
7667 | unsigned int size; |
7668 | char tmp[16]; | |
7669 | char *buf = NULL; | |
2c42cfbf | 7670 | char *name; |
413ee3b4 | 7671 | |
0b3589be PZ |
7672 | if (vma->vm_flags & VM_READ) |
7673 | prot |= PROT_READ; | |
7674 | if (vma->vm_flags & VM_WRITE) | |
7675 | prot |= PROT_WRITE; | |
7676 | if (vma->vm_flags & VM_EXEC) | |
7677 | prot |= PROT_EXEC; | |
7678 | ||
7679 | if (vma->vm_flags & VM_MAYSHARE) | |
7680 | flags = MAP_SHARED; | |
7681 | else | |
7682 | flags = MAP_PRIVATE; | |
7683 | ||
7684 | if (vma->vm_flags & VM_DENYWRITE) | |
7685 | flags |= MAP_DENYWRITE; | |
7686 | if (vma->vm_flags & VM_MAYEXEC) | |
7687 | flags |= MAP_EXECUTABLE; | |
7688 | if (vma->vm_flags & VM_LOCKED) | |
7689 | flags |= MAP_LOCKED; | |
7690 | if (vma->vm_flags & VM_HUGETLB) | |
7691 | flags |= MAP_HUGETLB; | |
7692 | ||
0a4a9391 | 7693 | if (file) { |
13d7a241 SE |
7694 | struct inode *inode; |
7695 | dev_t dev; | |
3ea2f2b9 | 7696 | |
2c42cfbf | 7697 | buf = kmalloc(PATH_MAX, GFP_KERNEL); |
0a4a9391 | 7698 | if (!buf) { |
c7e548b4 ON |
7699 | name = "//enomem"; |
7700 | goto cpy_name; | |
0a4a9391 | 7701 | } |
413ee3b4 | 7702 | /* |
3ea2f2b9 | 7703 | * d_path() works from the end of the rb backwards, so we |
413ee3b4 AB |
7704 | * need to add enough zero bytes after the string to handle |
7705 | * the 64bit alignment we do later. | |
7706 | */ | |
9bf39ab2 | 7707 | name = file_path(file, buf, PATH_MAX - sizeof(u64)); |
0a4a9391 | 7708 | if (IS_ERR(name)) { |
c7e548b4 ON |
7709 | name = "//toolong"; |
7710 | goto cpy_name; | |
0a4a9391 | 7711 | } |
13d7a241 SE |
7712 | inode = file_inode(vma->vm_file); |
7713 | dev = inode->i_sb->s_dev; | |
7714 | ino = inode->i_ino; | |
7715 | gen = inode->i_generation; | |
7716 | maj = MAJOR(dev); | |
7717 | min = MINOR(dev); | |
f972eb63 | 7718 | |
c7e548b4 | 7719 | goto got_name; |
0a4a9391 | 7720 | } else { |
fbe26abe JO |
7721 | if (vma->vm_ops && vma->vm_ops->name) { |
7722 | name = (char *) vma->vm_ops->name(vma); | |
7723 | if (name) | |
7724 | goto cpy_name; | |
7725 | } | |
7726 | ||
2c42cfbf | 7727 | name = (char *)arch_vma_name(vma); |
c7e548b4 ON |
7728 | if (name) |
7729 | goto cpy_name; | |
089dd79d | 7730 | |
32c5fb7e | 7731 | if (vma->vm_start <= vma->vm_mm->start_brk && |
3af9e859 | 7732 | vma->vm_end >= vma->vm_mm->brk) { |
c7e548b4 ON |
7733 | name = "[heap]"; |
7734 | goto cpy_name; | |
32c5fb7e ON |
7735 | } |
7736 | if (vma->vm_start <= vma->vm_mm->start_stack && | |
3af9e859 | 7737 | vma->vm_end >= vma->vm_mm->start_stack) { |
c7e548b4 ON |
7738 | name = "[stack]"; |
7739 | goto cpy_name; | |
089dd79d PZ |
7740 | } |
7741 | ||
c7e548b4 ON |
7742 | name = "//anon"; |
7743 | goto cpy_name; | |
0a4a9391 PZ |
7744 | } |
7745 | ||
c7e548b4 ON |
7746 | cpy_name: |
7747 | strlcpy(tmp, name, sizeof(tmp)); | |
7748 | name = tmp; | |
0a4a9391 | 7749 | got_name: |
2c42cfbf PZ |
7750 | /* |
7751 | * Since our buffer works in 8 byte units we need to align our string | |
7752 | * size to a multiple of 8. However, we must guarantee the tail end is | |
7753 | * zero'd out to avoid leaking random bits to userspace. | |
7754 | */ | |
7755 | size = strlen(name)+1; | |
7756 | while (!IS_ALIGNED(size, sizeof(u64))) | |
7757 | name[size++] = '\0'; | |
0a4a9391 PZ |
7758 | |
7759 | mmap_event->file_name = name; | |
7760 | mmap_event->file_size = size; | |
13d7a241 SE |
7761 | mmap_event->maj = maj; |
7762 | mmap_event->min = min; | |
7763 | mmap_event->ino = ino; | |
7764 | mmap_event->ino_generation = gen; | |
f972eb63 PZ |
7765 | mmap_event->prot = prot; |
7766 | mmap_event->flags = flags; | |
0a4a9391 | 7767 | |
2fe85427 SE |
7768 | if (!(vma->vm_flags & VM_EXEC)) |
7769 | mmap_event->event_id.header.misc |= PERF_RECORD_MISC_MMAP_DATA; | |
7770 | ||
cdd6c482 | 7771 | mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size; |
0a4a9391 | 7772 | |
aab5b71e | 7773 | perf_iterate_sb(perf_event_mmap_output, |
52d857a8 JO |
7774 | mmap_event, |
7775 | NULL); | |
665c2142 | 7776 | |
0a4a9391 PZ |
7777 | kfree(buf); |
7778 | } | |
7779 | ||
375637bc AS |
7780 | /* |
7781 | * Check whether inode and address range match filter criteria. | |
7782 | */ | |
7783 | static bool perf_addr_filter_match(struct perf_addr_filter *filter, | |
7784 | struct file *file, unsigned long offset, | |
7785 | unsigned long size) | |
7786 | { | |
7f635ff1 MP |
7787 | /* d_inode(NULL) won't be equal to any mapped user-space file */ |
7788 | if (!filter->path.dentry) | |
7789 | return false; | |
7790 | ||
9511bce9 | 7791 | if (d_inode(filter->path.dentry) != file_inode(file)) |
375637bc AS |
7792 | return false; |
7793 | ||
7794 | if (filter->offset > offset + size) | |
7795 | return false; | |
7796 | ||
7797 | if (filter->offset + filter->size < offset) | |
7798 | return false; | |
7799 | ||
7800 | return true; | |
7801 | } | |
7802 | ||
c60f83b8 AS |
7803 | static bool perf_addr_filter_vma_adjust(struct perf_addr_filter *filter, |
7804 | struct vm_area_struct *vma, | |
7805 | struct perf_addr_filter_range *fr) | |
7806 | { | |
7807 | unsigned long vma_size = vma->vm_end - vma->vm_start; | |
7808 | unsigned long off = vma->vm_pgoff << PAGE_SHIFT; | |
7809 | struct file *file = vma->vm_file; | |
7810 | ||
7811 | if (!perf_addr_filter_match(filter, file, off, vma_size)) | |
7812 | return false; | |
7813 | ||
7814 | if (filter->offset < off) { | |
7815 | fr->start = vma->vm_start; | |
7816 | fr->size = min(vma_size, filter->size - (off - filter->offset)); | |
7817 | } else { | |
7818 | fr->start = vma->vm_start + filter->offset - off; | |
7819 | fr->size = min(vma->vm_end - fr->start, filter->size); | |
7820 | } | |
7821 | ||
7822 | return true; | |
7823 | } | |
7824 | ||
375637bc AS |
7825 | static void __perf_addr_filters_adjust(struct perf_event *event, void *data) |
7826 | { | |
7827 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
7828 | struct vm_area_struct *vma = data; | |
375637bc AS |
7829 | struct perf_addr_filter *filter; |
7830 | unsigned int restart = 0, count = 0; | |
c60f83b8 | 7831 | unsigned long flags; |
375637bc AS |
7832 | |
7833 | if (!has_addr_filter(event)) | |
7834 | return; | |
7835 | ||
c60f83b8 | 7836 | if (!vma->vm_file) |
375637bc AS |
7837 | return; |
7838 | ||
7839 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
7840 | list_for_each_entry(filter, &ifh->list, entry) { | |
c60f83b8 AS |
7841 | if (perf_addr_filter_vma_adjust(filter, vma, |
7842 | &event->addr_filter_ranges[count])) | |
375637bc | 7843 | restart++; |
375637bc AS |
7844 | |
7845 | count++; | |
7846 | } | |
7847 | ||
7848 | if (restart) | |
7849 | event->addr_filters_gen++; | |
7850 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
7851 | ||
7852 | if (restart) | |
767ae086 | 7853 | perf_event_stop(event, 1); |
375637bc AS |
7854 | } |
7855 | ||
7856 | /* | |
7857 | * Adjust all task's events' filters to the new vma | |
7858 | */ | |
7859 | static void perf_addr_filters_adjust(struct vm_area_struct *vma) | |
7860 | { | |
7861 | struct perf_event_context *ctx; | |
7862 | int ctxn; | |
7863 | ||
12b40a23 MP |
7864 | /* |
7865 | * Data tracing isn't supported yet and as such there is no need | |
7866 | * to keep track of anything that isn't related to executable code: | |
7867 | */ | |
7868 | if (!(vma->vm_flags & VM_EXEC)) | |
7869 | return; | |
7870 | ||
375637bc AS |
7871 | rcu_read_lock(); |
7872 | for_each_task_context_nr(ctxn) { | |
7873 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); | |
7874 | if (!ctx) | |
7875 | continue; | |
7876 | ||
aab5b71e | 7877 | perf_iterate_ctx(ctx, __perf_addr_filters_adjust, vma, true); |
375637bc AS |
7878 | } |
7879 | rcu_read_unlock(); | |
7880 | } | |
7881 | ||
3af9e859 | 7882 | void perf_event_mmap(struct vm_area_struct *vma) |
0a4a9391 | 7883 | { |
9ee318a7 PZ |
7884 | struct perf_mmap_event mmap_event; |
7885 | ||
cdd6c482 | 7886 | if (!atomic_read(&nr_mmap_events)) |
9ee318a7 PZ |
7887 | return; |
7888 | ||
7889 | mmap_event = (struct perf_mmap_event){ | |
089dd79d | 7890 | .vma = vma, |
573402db PZ |
7891 | /* .file_name */ |
7892 | /* .file_size */ | |
cdd6c482 | 7893 | .event_id = { |
573402db | 7894 | .header = { |
cdd6c482 | 7895 | .type = PERF_RECORD_MMAP, |
39447b38 | 7896 | .misc = PERF_RECORD_MISC_USER, |
573402db PZ |
7897 | /* .size */ |
7898 | }, | |
7899 | /* .pid */ | |
7900 | /* .tid */ | |
089dd79d PZ |
7901 | .start = vma->vm_start, |
7902 | .len = vma->vm_end - vma->vm_start, | |
3a0304e9 | 7903 | .pgoff = (u64)vma->vm_pgoff << PAGE_SHIFT, |
0a4a9391 | 7904 | }, |
13d7a241 SE |
7905 | /* .maj (attr_mmap2 only) */ |
7906 | /* .min (attr_mmap2 only) */ | |
7907 | /* .ino (attr_mmap2 only) */ | |
7908 | /* .ino_generation (attr_mmap2 only) */ | |
f972eb63 PZ |
7909 | /* .prot (attr_mmap2 only) */ |
7910 | /* .flags (attr_mmap2 only) */ | |
0a4a9391 PZ |
7911 | }; |
7912 | ||
375637bc | 7913 | perf_addr_filters_adjust(vma); |
cdd6c482 | 7914 | perf_event_mmap_event(&mmap_event); |
0a4a9391 PZ |
7915 | } |
7916 | ||
68db7e98 AS |
7917 | void perf_event_aux_event(struct perf_event *event, unsigned long head, |
7918 | unsigned long size, u64 flags) | |
7919 | { | |
7920 | struct perf_output_handle handle; | |
7921 | struct perf_sample_data sample; | |
7922 | struct perf_aux_event { | |
7923 | struct perf_event_header header; | |
7924 | u64 offset; | |
7925 | u64 size; | |
7926 | u64 flags; | |
7927 | } rec = { | |
7928 | .header = { | |
7929 | .type = PERF_RECORD_AUX, | |
7930 | .misc = 0, | |
7931 | .size = sizeof(rec), | |
7932 | }, | |
7933 | .offset = head, | |
7934 | .size = size, | |
7935 | .flags = flags, | |
7936 | }; | |
7937 | int ret; | |
7938 | ||
7939 | perf_event_header__init_id(&rec.header, &sample, event); | |
7940 | ret = perf_output_begin(&handle, event, rec.header.size); | |
7941 | ||
7942 | if (ret) | |
7943 | return; | |
7944 | ||
7945 | perf_output_put(&handle, rec); | |
7946 | perf_event__output_id_sample(event, &handle, &sample); | |
7947 | ||
7948 | perf_output_end(&handle); | |
7949 | } | |
7950 | ||
f38b0dbb KL |
7951 | /* |
7952 | * Lost/dropped samples logging | |
7953 | */ | |
7954 | void perf_log_lost_samples(struct perf_event *event, u64 lost) | |
7955 | { | |
7956 | struct perf_output_handle handle; | |
7957 | struct perf_sample_data sample; | |
7958 | int ret; | |
7959 | ||
7960 | struct { | |
7961 | struct perf_event_header header; | |
7962 | u64 lost; | |
7963 | } lost_samples_event = { | |
7964 | .header = { | |
7965 | .type = PERF_RECORD_LOST_SAMPLES, | |
7966 | .misc = 0, | |
7967 | .size = sizeof(lost_samples_event), | |
7968 | }, | |
7969 | .lost = lost, | |
7970 | }; | |
7971 | ||
7972 | perf_event_header__init_id(&lost_samples_event.header, &sample, event); | |
7973 | ||
7974 | ret = perf_output_begin(&handle, event, | |
7975 | lost_samples_event.header.size); | |
7976 | if (ret) | |
7977 | return; | |
7978 | ||
7979 | perf_output_put(&handle, lost_samples_event); | |
7980 | perf_event__output_id_sample(event, &handle, &sample); | |
7981 | perf_output_end(&handle); | |
7982 | } | |
7983 | ||
45ac1403 AH |
7984 | /* |
7985 | * context_switch tracking | |
7986 | */ | |
7987 | ||
7988 | struct perf_switch_event { | |
7989 | struct task_struct *task; | |
7990 | struct task_struct *next_prev; | |
7991 | ||
7992 | struct { | |
7993 | struct perf_event_header header; | |
7994 | u32 next_prev_pid; | |
7995 | u32 next_prev_tid; | |
7996 | } event_id; | |
7997 | }; | |
7998 | ||
7999 | static int perf_event_switch_match(struct perf_event *event) | |
8000 | { | |
8001 | return event->attr.context_switch; | |
8002 | } | |
8003 | ||
8004 | static void perf_event_switch_output(struct perf_event *event, void *data) | |
8005 | { | |
8006 | struct perf_switch_event *se = data; | |
8007 | struct perf_output_handle handle; | |
8008 | struct perf_sample_data sample; | |
8009 | int ret; | |
8010 | ||
8011 | if (!perf_event_switch_match(event)) | |
8012 | return; | |
8013 | ||
8014 | /* Only CPU-wide events are allowed to see next/prev pid/tid */ | |
8015 | if (event->ctx->task) { | |
8016 | se->event_id.header.type = PERF_RECORD_SWITCH; | |
8017 | se->event_id.header.size = sizeof(se->event_id.header); | |
8018 | } else { | |
8019 | se->event_id.header.type = PERF_RECORD_SWITCH_CPU_WIDE; | |
8020 | se->event_id.header.size = sizeof(se->event_id); | |
8021 | se->event_id.next_prev_pid = | |
8022 | perf_event_pid(event, se->next_prev); | |
8023 | se->event_id.next_prev_tid = | |
8024 | perf_event_tid(event, se->next_prev); | |
8025 | } | |
8026 | ||
8027 | perf_event_header__init_id(&se->event_id.header, &sample, event); | |
8028 | ||
8029 | ret = perf_output_begin(&handle, event, se->event_id.header.size); | |
8030 | if (ret) | |
8031 | return; | |
8032 | ||
8033 | if (event->ctx->task) | |
8034 | perf_output_put(&handle, se->event_id.header); | |
8035 | else | |
8036 | perf_output_put(&handle, se->event_id); | |
8037 | ||
8038 | perf_event__output_id_sample(event, &handle, &sample); | |
8039 | ||
8040 | perf_output_end(&handle); | |
8041 | } | |
8042 | ||
8043 | static void perf_event_switch(struct task_struct *task, | |
8044 | struct task_struct *next_prev, bool sched_in) | |
8045 | { | |
8046 | struct perf_switch_event switch_event; | |
8047 | ||
8048 | /* N.B. caller checks nr_switch_events != 0 */ | |
8049 | ||
8050 | switch_event = (struct perf_switch_event){ | |
8051 | .task = task, | |
8052 | .next_prev = next_prev, | |
8053 | .event_id = { | |
8054 | .header = { | |
8055 | /* .type */ | |
8056 | .misc = sched_in ? 0 : PERF_RECORD_MISC_SWITCH_OUT, | |
8057 | /* .size */ | |
8058 | }, | |
8059 | /* .next_prev_pid */ | |
8060 | /* .next_prev_tid */ | |
8061 | }, | |
8062 | }; | |
8063 | ||
101592b4 AB |
8064 | if (!sched_in && task->state == TASK_RUNNING) |
8065 | switch_event.event_id.header.misc |= | |
8066 | PERF_RECORD_MISC_SWITCH_OUT_PREEMPT; | |
8067 | ||
aab5b71e | 8068 | perf_iterate_sb(perf_event_switch_output, |
45ac1403 AH |
8069 | &switch_event, |
8070 | NULL); | |
8071 | } | |
8072 | ||
a78ac325 PZ |
8073 | /* |
8074 | * IRQ throttle logging | |
8075 | */ | |
8076 | ||
cdd6c482 | 8077 | static void perf_log_throttle(struct perf_event *event, int enable) |
a78ac325 PZ |
8078 | { |
8079 | struct perf_output_handle handle; | |
c980d109 | 8080 | struct perf_sample_data sample; |
a78ac325 PZ |
8081 | int ret; |
8082 | ||
8083 | struct { | |
8084 | struct perf_event_header header; | |
8085 | u64 time; | |
cca3f454 | 8086 | u64 id; |
7f453c24 | 8087 | u64 stream_id; |
a78ac325 PZ |
8088 | } throttle_event = { |
8089 | .header = { | |
cdd6c482 | 8090 | .type = PERF_RECORD_THROTTLE, |
a78ac325 PZ |
8091 | .misc = 0, |
8092 | .size = sizeof(throttle_event), | |
8093 | }, | |
34f43927 | 8094 | .time = perf_event_clock(event), |
cdd6c482 IM |
8095 | .id = primary_event_id(event), |
8096 | .stream_id = event->id, | |
a78ac325 PZ |
8097 | }; |
8098 | ||
966ee4d6 | 8099 | if (enable) |
cdd6c482 | 8100 | throttle_event.header.type = PERF_RECORD_UNTHROTTLE; |
966ee4d6 | 8101 | |
c980d109 ACM |
8102 | perf_event_header__init_id(&throttle_event.header, &sample, event); |
8103 | ||
8104 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 8105 | throttle_event.header.size); |
a78ac325 PZ |
8106 | if (ret) |
8107 | return; | |
8108 | ||
8109 | perf_output_put(&handle, throttle_event); | |
c980d109 | 8110 | perf_event__output_id_sample(event, &handle, &sample); |
a78ac325 PZ |
8111 | perf_output_end(&handle); |
8112 | } | |
8113 | ||
76193a94 SL |
8114 | /* |
8115 | * ksymbol register/unregister tracking | |
8116 | */ | |
8117 | ||
8118 | struct perf_ksymbol_event { | |
8119 | const char *name; | |
8120 | int name_len; | |
8121 | struct { | |
8122 | struct perf_event_header header; | |
8123 | u64 addr; | |
8124 | u32 len; | |
8125 | u16 ksym_type; | |
8126 | u16 flags; | |
8127 | } event_id; | |
8128 | }; | |
8129 | ||
8130 | static int perf_event_ksymbol_match(struct perf_event *event) | |
8131 | { | |
8132 | return event->attr.ksymbol; | |
8133 | } | |
8134 | ||
8135 | static void perf_event_ksymbol_output(struct perf_event *event, void *data) | |
8136 | { | |
8137 | struct perf_ksymbol_event *ksymbol_event = data; | |
8138 | struct perf_output_handle handle; | |
8139 | struct perf_sample_data sample; | |
8140 | int ret; | |
8141 | ||
8142 | if (!perf_event_ksymbol_match(event)) | |
8143 | return; | |
8144 | ||
8145 | perf_event_header__init_id(&ksymbol_event->event_id.header, | |
8146 | &sample, event); | |
8147 | ret = perf_output_begin(&handle, event, | |
8148 | ksymbol_event->event_id.header.size); | |
8149 | if (ret) | |
8150 | return; | |
8151 | ||
8152 | perf_output_put(&handle, ksymbol_event->event_id); | |
8153 | __output_copy(&handle, ksymbol_event->name, ksymbol_event->name_len); | |
8154 | perf_event__output_id_sample(event, &handle, &sample); | |
8155 | ||
8156 | perf_output_end(&handle); | |
8157 | } | |
8158 | ||
8159 | void perf_event_ksymbol(u16 ksym_type, u64 addr, u32 len, bool unregister, | |
8160 | const char *sym) | |
8161 | { | |
8162 | struct perf_ksymbol_event ksymbol_event; | |
8163 | char name[KSYM_NAME_LEN]; | |
8164 | u16 flags = 0; | |
8165 | int name_len; | |
8166 | ||
8167 | if (!atomic_read(&nr_ksymbol_events)) | |
8168 | return; | |
8169 | ||
8170 | if (ksym_type >= PERF_RECORD_KSYMBOL_TYPE_MAX || | |
8171 | ksym_type == PERF_RECORD_KSYMBOL_TYPE_UNKNOWN) | |
8172 | goto err; | |
8173 | ||
8174 | strlcpy(name, sym, KSYM_NAME_LEN); | |
8175 | name_len = strlen(name) + 1; | |
8176 | while (!IS_ALIGNED(name_len, sizeof(u64))) | |
8177 | name[name_len++] = '\0'; | |
8178 | BUILD_BUG_ON(KSYM_NAME_LEN % sizeof(u64)); | |
8179 | ||
8180 | if (unregister) | |
8181 | flags |= PERF_RECORD_KSYMBOL_FLAGS_UNREGISTER; | |
8182 | ||
8183 | ksymbol_event = (struct perf_ksymbol_event){ | |
8184 | .name = name, | |
8185 | .name_len = name_len, | |
8186 | .event_id = { | |
8187 | .header = { | |
8188 | .type = PERF_RECORD_KSYMBOL, | |
8189 | .size = sizeof(ksymbol_event.event_id) + | |
8190 | name_len, | |
8191 | }, | |
8192 | .addr = addr, | |
8193 | .len = len, | |
8194 | .ksym_type = ksym_type, | |
8195 | .flags = flags, | |
8196 | }, | |
8197 | }; | |
8198 | ||
8199 | perf_iterate_sb(perf_event_ksymbol_output, &ksymbol_event, NULL); | |
8200 | return; | |
8201 | err: | |
8202 | WARN_ONCE(1, "%s: Invalid KSYMBOL type 0x%x\n", __func__, ksym_type); | |
8203 | } | |
8204 | ||
6ee52e2a SL |
8205 | /* |
8206 | * bpf program load/unload tracking | |
8207 | */ | |
8208 | ||
8209 | struct perf_bpf_event { | |
8210 | struct bpf_prog *prog; | |
8211 | struct { | |
8212 | struct perf_event_header header; | |
8213 | u16 type; | |
8214 | u16 flags; | |
8215 | u32 id; | |
8216 | u8 tag[BPF_TAG_SIZE]; | |
8217 | } event_id; | |
8218 | }; | |
8219 | ||
8220 | static int perf_event_bpf_match(struct perf_event *event) | |
8221 | { | |
8222 | return event->attr.bpf_event; | |
8223 | } | |
8224 | ||
8225 | static void perf_event_bpf_output(struct perf_event *event, void *data) | |
8226 | { | |
8227 | struct perf_bpf_event *bpf_event = data; | |
8228 | struct perf_output_handle handle; | |
8229 | struct perf_sample_data sample; | |
8230 | int ret; | |
8231 | ||
8232 | if (!perf_event_bpf_match(event)) | |
8233 | return; | |
8234 | ||
8235 | perf_event_header__init_id(&bpf_event->event_id.header, | |
8236 | &sample, event); | |
8237 | ret = perf_output_begin(&handle, event, | |
8238 | bpf_event->event_id.header.size); | |
8239 | if (ret) | |
8240 | return; | |
8241 | ||
8242 | perf_output_put(&handle, bpf_event->event_id); | |
8243 | perf_event__output_id_sample(event, &handle, &sample); | |
8244 | ||
8245 | perf_output_end(&handle); | |
8246 | } | |
8247 | ||
8248 | static void perf_event_bpf_emit_ksymbols(struct bpf_prog *prog, | |
8249 | enum perf_bpf_event_type type) | |
8250 | { | |
8251 | bool unregister = type == PERF_BPF_EVENT_PROG_UNLOAD; | |
8252 | char sym[KSYM_NAME_LEN]; | |
8253 | int i; | |
8254 | ||
8255 | if (prog->aux->func_cnt == 0) { | |
8256 | bpf_get_prog_name(prog, sym); | |
8257 | perf_event_ksymbol(PERF_RECORD_KSYMBOL_TYPE_BPF, | |
8258 | (u64)(unsigned long)prog->bpf_func, | |
8259 | prog->jited_len, unregister, sym); | |
8260 | } else { | |
8261 | for (i = 0; i < prog->aux->func_cnt; i++) { | |
8262 | struct bpf_prog *subprog = prog->aux->func[i]; | |
8263 | ||
8264 | bpf_get_prog_name(subprog, sym); | |
8265 | perf_event_ksymbol( | |
8266 | PERF_RECORD_KSYMBOL_TYPE_BPF, | |
8267 | (u64)(unsigned long)subprog->bpf_func, | |
8268 | subprog->jited_len, unregister, sym); | |
8269 | } | |
8270 | } | |
8271 | } | |
8272 | ||
8273 | void perf_event_bpf_event(struct bpf_prog *prog, | |
8274 | enum perf_bpf_event_type type, | |
8275 | u16 flags) | |
8276 | { | |
8277 | struct perf_bpf_event bpf_event; | |
8278 | ||
8279 | if (type <= PERF_BPF_EVENT_UNKNOWN || | |
8280 | type >= PERF_BPF_EVENT_MAX) | |
8281 | return; | |
8282 | ||
8283 | switch (type) { | |
8284 | case PERF_BPF_EVENT_PROG_LOAD: | |
8285 | case PERF_BPF_EVENT_PROG_UNLOAD: | |
8286 | if (atomic_read(&nr_ksymbol_events)) | |
8287 | perf_event_bpf_emit_ksymbols(prog, type); | |
8288 | break; | |
8289 | default: | |
8290 | break; | |
8291 | } | |
8292 | ||
8293 | if (!atomic_read(&nr_bpf_events)) | |
8294 | return; | |
8295 | ||
8296 | bpf_event = (struct perf_bpf_event){ | |
8297 | .prog = prog, | |
8298 | .event_id = { | |
8299 | .header = { | |
8300 | .type = PERF_RECORD_BPF_EVENT, | |
8301 | .size = sizeof(bpf_event.event_id), | |
8302 | }, | |
8303 | .type = type, | |
8304 | .flags = flags, | |
8305 | .id = prog->aux->id, | |
8306 | }, | |
8307 | }; | |
8308 | ||
8309 | BUILD_BUG_ON(BPF_TAG_SIZE % sizeof(u64)); | |
8310 | ||
8311 | memcpy(bpf_event.event_id.tag, prog->tag, BPF_TAG_SIZE); | |
8312 | perf_iterate_sb(perf_event_bpf_output, &bpf_event, NULL); | |
8313 | } | |
8314 | ||
8d4e6c4c AS |
8315 | void perf_event_itrace_started(struct perf_event *event) |
8316 | { | |
8317 | event->attach_state |= PERF_ATTACH_ITRACE; | |
8318 | } | |
8319 | ||
ec0d7729 AS |
8320 | static void perf_log_itrace_start(struct perf_event *event) |
8321 | { | |
8322 | struct perf_output_handle handle; | |
8323 | struct perf_sample_data sample; | |
8324 | struct perf_aux_event { | |
8325 | struct perf_event_header header; | |
8326 | u32 pid; | |
8327 | u32 tid; | |
8328 | } rec; | |
8329 | int ret; | |
8330 | ||
8331 | if (event->parent) | |
8332 | event = event->parent; | |
8333 | ||
8334 | if (!(event->pmu->capabilities & PERF_PMU_CAP_ITRACE) || | |
8d4e6c4c | 8335 | event->attach_state & PERF_ATTACH_ITRACE) |
ec0d7729 AS |
8336 | return; |
8337 | ||
ec0d7729 AS |
8338 | rec.header.type = PERF_RECORD_ITRACE_START; |
8339 | rec.header.misc = 0; | |
8340 | rec.header.size = sizeof(rec); | |
8341 | rec.pid = perf_event_pid(event, current); | |
8342 | rec.tid = perf_event_tid(event, current); | |
8343 | ||
8344 | perf_event_header__init_id(&rec.header, &sample, event); | |
8345 | ret = perf_output_begin(&handle, event, rec.header.size); | |
8346 | ||
8347 | if (ret) | |
8348 | return; | |
8349 | ||
8350 | perf_output_put(&handle, rec); | |
8351 | perf_event__output_id_sample(event, &handle, &sample); | |
8352 | ||
8353 | perf_output_end(&handle); | |
8354 | } | |
8355 | ||
475113d9 JO |
8356 | static int |
8357 | __perf_event_account_interrupt(struct perf_event *event, int throttle) | |
f6c7d5fe | 8358 | { |
cdd6c482 | 8359 | struct hw_perf_event *hwc = &event->hw; |
79f14641 | 8360 | int ret = 0; |
475113d9 | 8361 | u64 seq; |
96398826 | 8362 | |
e050e3f0 SE |
8363 | seq = __this_cpu_read(perf_throttled_seq); |
8364 | if (seq != hwc->interrupts_seq) { | |
8365 | hwc->interrupts_seq = seq; | |
8366 | hwc->interrupts = 1; | |
8367 | } else { | |
8368 | hwc->interrupts++; | |
8369 | if (unlikely(throttle | |
8370 | && hwc->interrupts >= max_samples_per_tick)) { | |
8371 | __this_cpu_inc(perf_throttled_count); | |
555e0c1e | 8372 | tick_dep_set_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
163ec435 PZ |
8373 | hwc->interrupts = MAX_INTERRUPTS; |
8374 | perf_log_throttle(event, 0); | |
a78ac325 PZ |
8375 | ret = 1; |
8376 | } | |
e050e3f0 | 8377 | } |
60db5e09 | 8378 | |
cdd6c482 | 8379 | if (event->attr.freq) { |
def0a9b2 | 8380 | u64 now = perf_clock(); |
abd50713 | 8381 | s64 delta = now - hwc->freq_time_stamp; |
bd2b5b12 | 8382 | |
abd50713 | 8383 | hwc->freq_time_stamp = now; |
bd2b5b12 | 8384 | |
abd50713 | 8385 | if (delta > 0 && delta < 2*TICK_NSEC) |
f39d47ff | 8386 | perf_adjust_period(event, delta, hwc->last_period, true); |
bd2b5b12 PZ |
8387 | } |
8388 | ||
475113d9 JO |
8389 | return ret; |
8390 | } | |
8391 | ||
8392 | int perf_event_account_interrupt(struct perf_event *event) | |
8393 | { | |
8394 | return __perf_event_account_interrupt(event, 1); | |
8395 | } | |
8396 | ||
8397 | /* | |
8398 | * Generic event overflow handling, sampling. | |
8399 | */ | |
8400 | ||
8401 | static int __perf_event_overflow(struct perf_event *event, | |
8402 | int throttle, struct perf_sample_data *data, | |
8403 | struct pt_regs *regs) | |
8404 | { | |
8405 | int events = atomic_read(&event->event_limit); | |
8406 | int ret = 0; | |
8407 | ||
8408 | /* | |
8409 | * Non-sampling counters might still use the PMI to fold short | |
8410 | * hardware counters, ignore those. | |
8411 | */ | |
8412 | if (unlikely(!is_sampling_event(event))) | |
8413 | return 0; | |
8414 | ||
8415 | ret = __perf_event_account_interrupt(event, throttle); | |
cc1582c2 | 8416 | |
2023b359 PZ |
8417 | /* |
8418 | * XXX event_limit might not quite work as expected on inherited | |
cdd6c482 | 8419 | * events |
2023b359 PZ |
8420 | */ |
8421 | ||
cdd6c482 IM |
8422 | event->pending_kill = POLL_IN; |
8423 | if (events && atomic_dec_and_test(&event->event_limit)) { | |
79f14641 | 8424 | ret = 1; |
cdd6c482 | 8425 | event->pending_kill = POLL_HUP; |
5aab90ce JO |
8426 | |
8427 | perf_event_disable_inatomic(event); | |
79f14641 PZ |
8428 | } |
8429 | ||
aa6a5f3c | 8430 | READ_ONCE(event->overflow_handler)(event, data, regs); |
453f19ee | 8431 | |
fed66e2c | 8432 | if (*perf_event_fasync(event) && event->pending_kill) { |
a8b0ca17 PZ |
8433 | event->pending_wakeup = 1; |
8434 | irq_work_queue(&event->pending); | |
f506b3dc PZ |
8435 | } |
8436 | ||
79f14641 | 8437 | return ret; |
f6c7d5fe PZ |
8438 | } |
8439 | ||
a8b0ca17 | 8440 | int perf_event_overflow(struct perf_event *event, |
5622f295 MM |
8441 | struct perf_sample_data *data, |
8442 | struct pt_regs *regs) | |
850bc73f | 8443 | { |
a8b0ca17 | 8444 | return __perf_event_overflow(event, 1, data, regs); |
850bc73f PZ |
8445 | } |
8446 | ||
15dbf27c | 8447 | /* |
cdd6c482 | 8448 | * Generic software event infrastructure |
15dbf27c PZ |
8449 | */ |
8450 | ||
b28ab83c PZ |
8451 | struct swevent_htable { |
8452 | struct swevent_hlist *swevent_hlist; | |
8453 | struct mutex hlist_mutex; | |
8454 | int hlist_refcount; | |
8455 | ||
8456 | /* Recursion avoidance in each contexts */ | |
8457 | int recursion[PERF_NR_CONTEXTS]; | |
8458 | }; | |
8459 | ||
8460 | static DEFINE_PER_CPU(struct swevent_htable, swevent_htable); | |
8461 | ||
7b4b6658 | 8462 | /* |
cdd6c482 IM |
8463 | * We directly increment event->count and keep a second value in |
8464 | * event->hw.period_left to count intervals. This period event | |
7b4b6658 PZ |
8465 | * is kept in the range [-sample_period, 0] so that we can use the |
8466 | * sign as trigger. | |
8467 | */ | |
8468 | ||
ab573844 | 8469 | u64 perf_swevent_set_period(struct perf_event *event) |
15dbf27c | 8470 | { |
cdd6c482 | 8471 | struct hw_perf_event *hwc = &event->hw; |
7b4b6658 PZ |
8472 | u64 period = hwc->last_period; |
8473 | u64 nr, offset; | |
8474 | s64 old, val; | |
8475 | ||
8476 | hwc->last_period = hwc->sample_period; | |
15dbf27c PZ |
8477 | |
8478 | again: | |
e7850595 | 8479 | old = val = local64_read(&hwc->period_left); |
7b4b6658 PZ |
8480 | if (val < 0) |
8481 | return 0; | |
15dbf27c | 8482 | |
7b4b6658 PZ |
8483 | nr = div64_u64(period + val, period); |
8484 | offset = nr * period; | |
8485 | val -= offset; | |
e7850595 | 8486 | if (local64_cmpxchg(&hwc->period_left, old, val) != old) |
7b4b6658 | 8487 | goto again; |
15dbf27c | 8488 | |
7b4b6658 | 8489 | return nr; |
15dbf27c PZ |
8490 | } |
8491 | ||
0cff784a | 8492 | static void perf_swevent_overflow(struct perf_event *event, u64 overflow, |
a8b0ca17 | 8493 | struct perf_sample_data *data, |
5622f295 | 8494 | struct pt_regs *regs) |
15dbf27c | 8495 | { |
cdd6c482 | 8496 | struct hw_perf_event *hwc = &event->hw; |
850bc73f | 8497 | int throttle = 0; |
15dbf27c | 8498 | |
0cff784a PZ |
8499 | if (!overflow) |
8500 | overflow = perf_swevent_set_period(event); | |
15dbf27c | 8501 | |
7b4b6658 PZ |
8502 | if (hwc->interrupts == MAX_INTERRUPTS) |
8503 | return; | |
15dbf27c | 8504 | |
7b4b6658 | 8505 | for (; overflow; overflow--) { |
a8b0ca17 | 8506 | if (__perf_event_overflow(event, throttle, |
5622f295 | 8507 | data, regs)) { |
7b4b6658 PZ |
8508 | /* |
8509 | * We inhibit the overflow from happening when | |
8510 | * hwc->interrupts == MAX_INTERRUPTS. | |
8511 | */ | |
8512 | break; | |
8513 | } | |
cf450a73 | 8514 | throttle = 1; |
7b4b6658 | 8515 | } |
15dbf27c PZ |
8516 | } |
8517 | ||
a4eaf7f1 | 8518 | static void perf_swevent_event(struct perf_event *event, u64 nr, |
a8b0ca17 | 8519 | struct perf_sample_data *data, |
5622f295 | 8520 | struct pt_regs *regs) |
7b4b6658 | 8521 | { |
cdd6c482 | 8522 | struct hw_perf_event *hwc = &event->hw; |
d6d020e9 | 8523 | |
e7850595 | 8524 | local64_add(nr, &event->count); |
d6d020e9 | 8525 | |
0cff784a PZ |
8526 | if (!regs) |
8527 | return; | |
8528 | ||
6c7e550f | 8529 | if (!is_sampling_event(event)) |
7b4b6658 | 8530 | return; |
d6d020e9 | 8531 | |
5d81e5cf AV |
8532 | if ((event->attr.sample_type & PERF_SAMPLE_PERIOD) && !event->attr.freq) { |
8533 | data->period = nr; | |
8534 | return perf_swevent_overflow(event, 1, data, regs); | |
8535 | } else | |
8536 | data->period = event->hw.last_period; | |
8537 | ||
0cff784a | 8538 | if (nr == 1 && hwc->sample_period == 1 && !event->attr.freq) |
a8b0ca17 | 8539 | return perf_swevent_overflow(event, 1, data, regs); |
0cff784a | 8540 | |
e7850595 | 8541 | if (local64_add_negative(nr, &hwc->period_left)) |
7b4b6658 | 8542 | return; |
df1a132b | 8543 | |
a8b0ca17 | 8544 | perf_swevent_overflow(event, 0, data, regs); |
d6d020e9 PZ |
8545 | } |
8546 | ||
f5ffe02e FW |
8547 | static int perf_exclude_event(struct perf_event *event, |
8548 | struct pt_regs *regs) | |
8549 | { | |
a4eaf7f1 | 8550 | if (event->hw.state & PERF_HES_STOPPED) |
91b2f482 | 8551 | return 1; |
a4eaf7f1 | 8552 | |
f5ffe02e FW |
8553 | if (regs) { |
8554 | if (event->attr.exclude_user && user_mode(regs)) | |
8555 | return 1; | |
8556 | ||
8557 | if (event->attr.exclude_kernel && !user_mode(regs)) | |
8558 | return 1; | |
8559 | } | |
8560 | ||
8561 | return 0; | |
8562 | } | |
8563 | ||
cdd6c482 | 8564 | static int perf_swevent_match(struct perf_event *event, |
1c432d89 | 8565 | enum perf_type_id type, |
6fb2915d LZ |
8566 | u32 event_id, |
8567 | struct perf_sample_data *data, | |
8568 | struct pt_regs *regs) | |
15dbf27c | 8569 | { |
cdd6c482 | 8570 | if (event->attr.type != type) |
a21ca2ca | 8571 | return 0; |
f5ffe02e | 8572 | |
cdd6c482 | 8573 | if (event->attr.config != event_id) |
15dbf27c PZ |
8574 | return 0; |
8575 | ||
f5ffe02e FW |
8576 | if (perf_exclude_event(event, regs)) |
8577 | return 0; | |
15dbf27c PZ |
8578 | |
8579 | return 1; | |
8580 | } | |
8581 | ||
76e1d904 FW |
8582 | static inline u64 swevent_hash(u64 type, u32 event_id) |
8583 | { | |
8584 | u64 val = event_id | (type << 32); | |
8585 | ||
8586 | return hash_64(val, SWEVENT_HLIST_BITS); | |
8587 | } | |
8588 | ||
49f135ed FW |
8589 | static inline struct hlist_head * |
8590 | __find_swevent_head(struct swevent_hlist *hlist, u64 type, u32 event_id) | |
76e1d904 | 8591 | { |
49f135ed FW |
8592 | u64 hash = swevent_hash(type, event_id); |
8593 | ||
8594 | return &hlist->heads[hash]; | |
8595 | } | |
76e1d904 | 8596 | |
49f135ed FW |
8597 | /* For the read side: events when they trigger */ |
8598 | static inline struct hlist_head * | |
b28ab83c | 8599 | find_swevent_head_rcu(struct swevent_htable *swhash, u64 type, u32 event_id) |
49f135ed FW |
8600 | { |
8601 | struct swevent_hlist *hlist; | |
76e1d904 | 8602 | |
b28ab83c | 8603 | hlist = rcu_dereference(swhash->swevent_hlist); |
76e1d904 FW |
8604 | if (!hlist) |
8605 | return NULL; | |
8606 | ||
49f135ed FW |
8607 | return __find_swevent_head(hlist, type, event_id); |
8608 | } | |
8609 | ||
8610 | /* For the event head insertion and removal in the hlist */ | |
8611 | static inline struct hlist_head * | |
b28ab83c | 8612 | find_swevent_head(struct swevent_htable *swhash, struct perf_event *event) |
49f135ed FW |
8613 | { |
8614 | struct swevent_hlist *hlist; | |
8615 | u32 event_id = event->attr.config; | |
8616 | u64 type = event->attr.type; | |
8617 | ||
8618 | /* | |
8619 | * Event scheduling is always serialized against hlist allocation | |
8620 | * and release. Which makes the protected version suitable here. | |
8621 | * The context lock guarantees that. | |
8622 | */ | |
b28ab83c | 8623 | hlist = rcu_dereference_protected(swhash->swevent_hlist, |
49f135ed FW |
8624 | lockdep_is_held(&event->ctx->lock)); |
8625 | if (!hlist) | |
8626 | return NULL; | |
8627 | ||
8628 | return __find_swevent_head(hlist, type, event_id); | |
76e1d904 FW |
8629 | } |
8630 | ||
8631 | static void do_perf_sw_event(enum perf_type_id type, u32 event_id, | |
a8b0ca17 | 8632 | u64 nr, |
76e1d904 FW |
8633 | struct perf_sample_data *data, |
8634 | struct pt_regs *regs) | |
15dbf27c | 8635 | { |
4a32fea9 | 8636 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 8637 | struct perf_event *event; |
76e1d904 | 8638 | struct hlist_head *head; |
15dbf27c | 8639 | |
76e1d904 | 8640 | rcu_read_lock(); |
b28ab83c | 8641 | head = find_swevent_head_rcu(swhash, type, event_id); |
76e1d904 FW |
8642 | if (!head) |
8643 | goto end; | |
8644 | ||
b67bfe0d | 8645 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
6fb2915d | 8646 | if (perf_swevent_match(event, type, event_id, data, regs)) |
a8b0ca17 | 8647 | perf_swevent_event(event, nr, data, regs); |
15dbf27c | 8648 | } |
76e1d904 FW |
8649 | end: |
8650 | rcu_read_unlock(); | |
15dbf27c PZ |
8651 | } |
8652 | ||
86038c5e PZI |
8653 | DEFINE_PER_CPU(struct pt_regs, __perf_regs[4]); |
8654 | ||
4ed7c92d | 8655 | int perf_swevent_get_recursion_context(void) |
96f6d444 | 8656 | { |
4a32fea9 | 8657 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
96f6d444 | 8658 | |
b28ab83c | 8659 | return get_recursion_context(swhash->recursion); |
96f6d444 | 8660 | } |
645e8cc0 | 8661 | EXPORT_SYMBOL_GPL(perf_swevent_get_recursion_context); |
96f6d444 | 8662 | |
98b5c2c6 | 8663 | void perf_swevent_put_recursion_context(int rctx) |
15dbf27c | 8664 | { |
4a32fea9 | 8665 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
927c7a9e | 8666 | |
b28ab83c | 8667 | put_recursion_context(swhash->recursion, rctx); |
ce71b9df | 8668 | } |
15dbf27c | 8669 | |
86038c5e | 8670 | void ___perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) |
b8e83514 | 8671 | { |
a4234bfc | 8672 | struct perf_sample_data data; |
4ed7c92d | 8673 | |
86038c5e | 8674 | if (WARN_ON_ONCE(!regs)) |
4ed7c92d | 8675 | return; |
a4234bfc | 8676 | |
fd0d000b | 8677 | perf_sample_data_init(&data, addr, 0); |
a8b0ca17 | 8678 | do_perf_sw_event(PERF_TYPE_SOFTWARE, event_id, nr, &data, regs); |
86038c5e PZI |
8679 | } |
8680 | ||
8681 | void __perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) | |
8682 | { | |
8683 | int rctx; | |
8684 | ||
8685 | preempt_disable_notrace(); | |
8686 | rctx = perf_swevent_get_recursion_context(); | |
8687 | if (unlikely(rctx < 0)) | |
8688 | goto fail; | |
8689 | ||
8690 | ___perf_sw_event(event_id, nr, regs, addr); | |
4ed7c92d PZ |
8691 | |
8692 | perf_swevent_put_recursion_context(rctx); | |
86038c5e | 8693 | fail: |
1c024eca | 8694 | preempt_enable_notrace(); |
b8e83514 PZ |
8695 | } |
8696 | ||
cdd6c482 | 8697 | static void perf_swevent_read(struct perf_event *event) |
15dbf27c | 8698 | { |
15dbf27c PZ |
8699 | } |
8700 | ||
a4eaf7f1 | 8701 | static int perf_swevent_add(struct perf_event *event, int flags) |
15dbf27c | 8702 | { |
4a32fea9 | 8703 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 8704 | struct hw_perf_event *hwc = &event->hw; |
76e1d904 FW |
8705 | struct hlist_head *head; |
8706 | ||
6c7e550f | 8707 | if (is_sampling_event(event)) { |
7b4b6658 | 8708 | hwc->last_period = hwc->sample_period; |
cdd6c482 | 8709 | perf_swevent_set_period(event); |
7b4b6658 | 8710 | } |
76e1d904 | 8711 | |
a4eaf7f1 PZ |
8712 | hwc->state = !(flags & PERF_EF_START); |
8713 | ||
b28ab83c | 8714 | head = find_swevent_head(swhash, event); |
12ca6ad2 | 8715 | if (WARN_ON_ONCE(!head)) |
76e1d904 FW |
8716 | return -EINVAL; |
8717 | ||
8718 | hlist_add_head_rcu(&event->hlist_entry, head); | |
6a694a60 | 8719 | perf_event_update_userpage(event); |
76e1d904 | 8720 | |
15dbf27c PZ |
8721 | return 0; |
8722 | } | |
8723 | ||
a4eaf7f1 | 8724 | static void perf_swevent_del(struct perf_event *event, int flags) |
15dbf27c | 8725 | { |
76e1d904 | 8726 | hlist_del_rcu(&event->hlist_entry); |
15dbf27c PZ |
8727 | } |
8728 | ||
a4eaf7f1 | 8729 | static void perf_swevent_start(struct perf_event *event, int flags) |
5c92d124 | 8730 | { |
a4eaf7f1 | 8731 | event->hw.state = 0; |
d6d020e9 | 8732 | } |
aa9c4c0f | 8733 | |
a4eaf7f1 | 8734 | static void perf_swevent_stop(struct perf_event *event, int flags) |
d6d020e9 | 8735 | { |
a4eaf7f1 | 8736 | event->hw.state = PERF_HES_STOPPED; |
bae43c99 IM |
8737 | } |
8738 | ||
49f135ed FW |
8739 | /* Deref the hlist from the update side */ |
8740 | static inline struct swevent_hlist * | |
b28ab83c | 8741 | swevent_hlist_deref(struct swevent_htable *swhash) |
49f135ed | 8742 | { |
b28ab83c PZ |
8743 | return rcu_dereference_protected(swhash->swevent_hlist, |
8744 | lockdep_is_held(&swhash->hlist_mutex)); | |
49f135ed FW |
8745 | } |
8746 | ||
b28ab83c | 8747 | static void swevent_hlist_release(struct swevent_htable *swhash) |
76e1d904 | 8748 | { |
b28ab83c | 8749 | struct swevent_hlist *hlist = swevent_hlist_deref(swhash); |
76e1d904 | 8750 | |
49f135ed | 8751 | if (!hlist) |
76e1d904 FW |
8752 | return; |
8753 | ||
70691d4a | 8754 | RCU_INIT_POINTER(swhash->swevent_hlist, NULL); |
fa4bbc4c | 8755 | kfree_rcu(hlist, rcu_head); |
76e1d904 FW |
8756 | } |
8757 | ||
3b364d7b | 8758 | static void swevent_hlist_put_cpu(int cpu) |
76e1d904 | 8759 | { |
b28ab83c | 8760 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 | 8761 | |
b28ab83c | 8762 | mutex_lock(&swhash->hlist_mutex); |
76e1d904 | 8763 | |
b28ab83c PZ |
8764 | if (!--swhash->hlist_refcount) |
8765 | swevent_hlist_release(swhash); | |
76e1d904 | 8766 | |
b28ab83c | 8767 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
8768 | } |
8769 | ||
3b364d7b | 8770 | static void swevent_hlist_put(void) |
76e1d904 FW |
8771 | { |
8772 | int cpu; | |
8773 | ||
76e1d904 | 8774 | for_each_possible_cpu(cpu) |
3b364d7b | 8775 | swevent_hlist_put_cpu(cpu); |
76e1d904 FW |
8776 | } |
8777 | ||
3b364d7b | 8778 | static int swevent_hlist_get_cpu(int cpu) |
76e1d904 | 8779 | { |
b28ab83c | 8780 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 FW |
8781 | int err = 0; |
8782 | ||
b28ab83c | 8783 | mutex_lock(&swhash->hlist_mutex); |
a63fbed7 TG |
8784 | if (!swevent_hlist_deref(swhash) && |
8785 | cpumask_test_cpu(cpu, perf_online_mask)) { | |
76e1d904 FW |
8786 | struct swevent_hlist *hlist; |
8787 | ||
8788 | hlist = kzalloc(sizeof(*hlist), GFP_KERNEL); | |
8789 | if (!hlist) { | |
8790 | err = -ENOMEM; | |
8791 | goto exit; | |
8792 | } | |
b28ab83c | 8793 | rcu_assign_pointer(swhash->swevent_hlist, hlist); |
76e1d904 | 8794 | } |
b28ab83c | 8795 | swhash->hlist_refcount++; |
9ed6060d | 8796 | exit: |
b28ab83c | 8797 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
8798 | |
8799 | return err; | |
8800 | } | |
8801 | ||
3b364d7b | 8802 | static int swevent_hlist_get(void) |
76e1d904 | 8803 | { |
3b364d7b | 8804 | int err, cpu, failed_cpu; |
76e1d904 | 8805 | |
a63fbed7 | 8806 | mutex_lock(&pmus_lock); |
76e1d904 | 8807 | for_each_possible_cpu(cpu) { |
3b364d7b | 8808 | err = swevent_hlist_get_cpu(cpu); |
76e1d904 FW |
8809 | if (err) { |
8810 | failed_cpu = cpu; | |
8811 | goto fail; | |
8812 | } | |
8813 | } | |
a63fbed7 | 8814 | mutex_unlock(&pmus_lock); |
76e1d904 | 8815 | return 0; |
9ed6060d | 8816 | fail: |
76e1d904 FW |
8817 | for_each_possible_cpu(cpu) { |
8818 | if (cpu == failed_cpu) | |
8819 | break; | |
3b364d7b | 8820 | swevent_hlist_put_cpu(cpu); |
76e1d904 | 8821 | } |
a63fbed7 | 8822 | mutex_unlock(&pmus_lock); |
76e1d904 FW |
8823 | return err; |
8824 | } | |
8825 | ||
c5905afb | 8826 | struct static_key perf_swevent_enabled[PERF_COUNT_SW_MAX]; |
95476b64 | 8827 | |
b0a873eb PZ |
8828 | static void sw_perf_event_destroy(struct perf_event *event) |
8829 | { | |
8830 | u64 event_id = event->attr.config; | |
95476b64 | 8831 | |
b0a873eb PZ |
8832 | WARN_ON(event->parent); |
8833 | ||
c5905afb | 8834 | static_key_slow_dec(&perf_swevent_enabled[event_id]); |
3b364d7b | 8835 | swevent_hlist_put(); |
b0a873eb PZ |
8836 | } |
8837 | ||
8838 | static int perf_swevent_init(struct perf_event *event) | |
8839 | { | |
8176cced | 8840 | u64 event_id = event->attr.config; |
b0a873eb PZ |
8841 | |
8842 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
8843 | return -ENOENT; | |
8844 | ||
2481c5fa SE |
8845 | /* |
8846 | * no branch sampling for software events | |
8847 | */ | |
8848 | if (has_branch_stack(event)) | |
8849 | return -EOPNOTSUPP; | |
8850 | ||
b0a873eb PZ |
8851 | switch (event_id) { |
8852 | case PERF_COUNT_SW_CPU_CLOCK: | |
8853 | case PERF_COUNT_SW_TASK_CLOCK: | |
8854 | return -ENOENT; | |
8855 | ||
8856 | default: | |
8857 | break; | |
8858 | } | |
8859 | ||
ce677831 | 8860 | if (event_id >= PERF_COUNT_SW_MAX) |
b0a873eb PZ |
8861 | return -ENOENT; |
8862 | ||
8863 | if (!event->parent) { | |
8864 | int err; | |
8865 | ||
3b364d7b | 8866 | err = swevent_hlist_get(); |
b0a873eb PZ |
8867 | if (err) |
8868 | return err; | |
8869 | ||
c5905afb | 8870 | static_key_slow_inc(&perf_swevent_enabled[event_id]); |
b0a873eb PZ |
8871 | event->destroy = sw_perf_event_destroy; |
8872 | } | |
8873 | ||
8874 | return 0; | |
8875 | } | |
8876 | ||
8877 | static struct pmu perf_swevent = { | |
89a1e187 | 8878 | .task_ctx_nr = perf_sw_context, |
95476b64 | 8879 | |
34f43927 PZ |
8880 | .capabilities = PERF_PMU_CAP_NO_NMI, |
8881 | ||
b0a873eb | 8882 | .event_init = perf_swevent_init, |
a4eaf7f1 PZ |
8883 | .add = perf_swevent_add, |
8884 | .del = perf_swevent_del, | |
8885 | .start = perf_swevent_start, | |
8886 | .stop = perf_swevent_stop, | |
1c024eca | 8887 | .read = perf_swevent_read, |
1c024eca PZ |
8888 | }; |
8889 | ||
b0a873eb PZ |
8890 | #ifdef CONFIG_EVENT_TRACING |
8891 | ||
1c024eca PZ |
8892 | static int perf_tp_filter_match(struct perf_event *event, |
8893 | struct perf_sample_data *data) | |
8894 | { | |
7e3f977e | 8895 | void *record = data->raw->frag.data; |
1c024eca | 8896 | |
b71b437e PZ |
8897 | /* only top level events have filters set */ |
8898 | if (event->parent) | |
8899 | event = event->parent; | |
8900 | ||
1c024eca PZ |
8901 | if (likely(!event->filter) || filter_match_preds(event->filter, record)) |
8902 | return 1; | |
8903 | return 0; | |
8904 | } | |
8905 | ||
8906 | static int perf_tp_event_match(struct perf_event *event, | |
8907 | struct perf_sample_data *data, | |
8908 | struct pt_regs *regs) | |
8909 | { | |
a0f7d0f7 FW |
8910 | if (event->hw.state & PERF_HES_STOPPED) |
8911 | return 0; | |
580d607c | 8912 | /* |
9fd2e48b | 8913 | * If exclude_kernel, only trace user-space tracepoints (uprobes) |
580d607c | 8914 | */ |
9fd2e48b | 8915 | if (event->attr.exclude_kernel && !user_mode(regs)) |
1c024eca PZ |
8916 | return 0; |
8917 | ||
8918 | if (!perf_tp_filter_match(event, data)) | |
8919 | return 0; | |
8920 | ||
8921 | return 1; | |
8922 | } | |
8923 | ||
85b67bcb AS |
8924 | void perf_trace_run_bpf_submit(void *raw_data, int size, int rctx, |
8925 | struct trace_event_call *call, u64 count, | |
8926 | struct pt_regs *regs, struct hlist_head *head, | |
8927 | struct task_struct *task) | |
8928 | { | |
e87c6bc3 | 8929 | if (bpf_prog_array_valid(call)) { |
85b67bcb | 8930 | *(struct pt_regs **)raw_data = regs; |
e87c6bc3 | 8931 | if (!trace_call_bpf(call, raw_data) || hlist_empty(head)) { |
85b67bcb AS |
8932 | perf_swevent_put_recursion_context(rctx); |
8933 | return; | |
8934 | } | |
8935 | } | |
8936 | perf_tp_event(call->event.type, count, raw_data, size, regs, head, | |
8fd0fbbe | 8937 | rctx, task); |
85b67bcb AS |
8938 | } |
8939 | EXPORT_SYMBOL_GPL(perf_trace_run_bpf_submit); | |
8940 | ||
1e1dcd93 | 8941 | void perf_tp_event(u16 event_type, u64 count, void *record, int entry_size, |
e6dab5ff | 8942 | struct pt_regs *regs, struct hlist_head *head, int rctx, |
8fd0fbbe | 8943 | struct task_struct *task) |
95476b64 FW |
8944 | { |
8945 | struct perf_sample_data data; | |
8fd0fbbe | 8946 | struct perf_event *event; |
1c024eca | 8947 | |
95476b64 | 8948 | struct perf_raw_record raw = { |
7e3f977e DB |
8949 | .frag = { |
8950 | .size = entry_size, | |
8951 | .data = record, | |
8952 | }, | |
95476b64 FW |
8953 | }; |
8954 | ||
1e1dcd93 | 8955 | perf_sample_data_init(&data, 0, 0); |
95476b64 FW |
8956 | data.raw = &raw; |
8957 | ||
1e1dcd93 AS |
8958 | perf_trace_buf_update(record, event_type); |
8959 | ||
8fd0fbbe | 8960 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
1c024eca | 8961 | if (perf_tp_event_match(event, &data, regs)) |
a8b0ca17 | 8962 | perf_swevent_event(event, count, &data, regs); |
4f41c013 | 8963 | } |
ecc55f84 | 8964 | |
e6dab5ff AV |
8965 | /* |
8966 | * If we got specified a target task, also iterate its context and | |
8967 | * deliver this event there too. | |
8968 | */ | |
8969 | if (task && task != current) { | |
8970 | struct perf_event_context *ctx; | |
8971 | struct trace_entry *entry = record; | |
8972 | ||
8973 | rcu_read_lock(); | |
8974 | ctx = rcu_dereference(task->perf_event_ctxp[perf_sw_context]); | |
8975 | if (!ctx) | |
8976 | goto unlock; | |
8977 | ||
8978 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
cd6fb677 JO |
8979 | if (event->cpu != smp_processor_id()) |
8980 | continue; | |
e6dab5ff AV |
8981 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
8982 | continue; | |
8983 | if (event->attr.config != entry->type) | |
8984 | continue; | |
8985 | if (perf_tp_event_match(event, &data, regs)) | |
8986 | perf_swevent_event(event, count, &data, regs); | |
8987 | } | |
8988 | unlock: | |
8989 | rcu_read_unlock(); | |
8990 | } | |
8991 | ||
ecc55f84 | 8992 | perf_swevent_put_recursion_context(rctx); |
95476b64 FW |
8993 | } |
8994 | EXPORT_SYMBOL_GPL(perf_tp_event); | |
8995 | ||
cdd6c482 | 8996 | static void tp_perf_event_destroy(struct perf_event *event) |
e077df4f | 8997 | { |
1c024eca | 8998 | perf_trace_destroy(event); |
e077df4f PZ |
8999 | } |
9000 | ||
b0a873eb | 9001 | static int perf_tp_event_init(struct perf_event *event) |
e077df4f | 9002 | { |
76e1d904 FW |
9003 | int err; |
9004 | ||
b0a873eb PZ |
9005 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
9006 | return -ENOENT; | |
9007 | ||
2481c5fa SE |
9008 | /* |
9009 | * no branch sampling for tracepoint events | |
9010 | */ | |
9011 | if (has_branch_stack(event)) | |
9012 | return -EOPNOTSUPP; | |
9013 | ||
1c024eca PZ |
9014 | err = perf_trace_init(event); |
9015 | if (err) | |
b0a873eb | 9016 | return err; |
e077df4f | 9017 | |
cdd6c482 | 9018 | event->destroy = tp_perf_event_destroy; |
e077df4f | 9019 | |
b0a873eb PZ |
9020 | return 0; |
9021 | } | |
9022 | ||
9023 | static struct pmu perf_tracepoint = { | |
89a1e187 PZ |
9024 | .task_ctx_nr = perf_sw_context, |
9025 | ||
b0a873eb | 9026 | .event_init = perf_tp_event_init, |
a4eaf7f1 PZ |
9027 | .add = perf_trace_add, |
9028 | .del = perf_trace_del, | |
9029 | .start = perf_swevent_start, | |
9030 | .stop = perf_swevent_stop, | |
b0a873eb | 9031 | .read = perf_swevent_read, |
b0a873eb PZ |
9032 | }; |
9033 | ||
33ea4b24 | 9034 | #if defined(CONFIG_KPROBE_EVENTS) || defined(CONFIG_UPROBE_EVENTS) |
e12f03d7 SL |
9035 | /* |
9036 | * Flags in config, used by dynamic PMU kprobe and uprobe | |
9037 | * The flags should match following PMU_FORMAT_ATTR(). | |
9038 | * | |
9039 | * PERF_PROBE_CONFIG_IS_RETPROBE if set, create kretprobe/uretprobe | |
9040 | * if not set, create kprobe/uprobe | |
a6ca88b2 SL |
9041 | * |
9042 | * The following values specify a reference counter (or semaphore in the | |
9043 | * terminology of tools like dtrace, systemtap, etc.) Userspace Statically | |
9044 | * Defined Tracepoints (USDT). Currently, we use 40 bit for the offset. | |
9045 | * | |
9046 | * PERF_UPROBE_REF_CTR_OFFSET_BITS # of bits in config as th offset | |
9047 | * PERF_UPROBE_REF_CTR_OFFSET_SHIFT # of bits to shift left | |
e12f03d7 SL |
9048 | */ |
9049 | enum perf_probe_config { | |
9050 | PERF_PROBE_CONFIG_IS_RETPROBE = 1U << 0, /* [k,u]retprobe */ | |
a6ca88b2 SL |
9051 | PERF_UPROBE_REF_CTR_OFFSET_BITS = 32, |
9052 | PERF_UPROBE_REF_CTR_OFFSET_SHIFT = 64 - PERF_UPROBE_REF_CTR_OFFSET_BITS, | |
e12f03d7 SL |
9053 | }; |
9054 | ||
9055 | PMU_FORMAT_ATTR(retprobe, "config:0"); | |
a6ca88b2 | 9056 | #endif |
e12f03d7 | 9057 | |
a6ca88b2 SL |
9058 | #ifdef CONFIG_KPROBE_EVENTS |
9059 | static struct attribute *kprobe_attrs[] = { | |
e12f03d7 SL |
9060 | &format_attr_retprobe.attr, |
9061 | NULL, | |
9062 | }; | |
9063 | ||
a6ca88b2 | 9064 | static struct attribute_group kprobe_format_group = { |
e12f03d7 | 9065 | .name = "format", |
a6ca88b2 | 9066 | .attrs = kprobe_attrs, |
e12f03d7 SL |
9067 | }; |
9068 | ||
a6ca88b2 SL |
9069 | static const struct attribute_group *kprobe_attr_groups[] = { |
9070 | &kprobe_format_group, | |
e12f03d7 SL |
9071 | NULL, |
9072 | }; | |
9073 | ||
9074 | static int perf_kprobe_event_init(struct perf_event *event); | |
9075 | static struct pmu perf_kprobe = { | |
9076 | .task_ctx_nr = perf_sw_context, | |
9077 | .event_init = perf_kprobe_event_init, | |
9078 | .add = perf_trace_add, | |
9079 | .del = perf_trace_del, | |
9080 | .start = perf_swevent_start, | |
9081 | .stop = perf_swevent_stop, | |
9082 | .read = perf_swevent_read, | |
a6ca88b2 | 9083 | .attr_groups = kprobe_attr_groups, |
e12f03d7 SL |
9084 | }; |
9085 | ||
9086 | static int perf_kprobe_event_init(struct perf_event *event) | |
9087 | { | |
9088 | int err; | |
9089 | bool is_retprobe; | |
9090 | ||
9091 | if (event->attr.type != perf_kprobe.type) | |
9092 | return -ENOENT; | |
32e6e967 SL |
9093 | |
9094 | if (!capable(CAP_SYS_ADMIN)) | |
9095 | return -EACCES; | |
9096 | ||
e12f03d7 SL |
9097 | /* |
9098 | * no branch sampling for probe events | |
9099 | */ | |
9100 | if (has_branch_stack(event)) | |
9101 | return -EOPNOTSUPP; | |
9102 | ||
9103 | is_retprobe = event->attr.config & PERF_PROBE_CONFIG_IS_RETPROBE; | |
9104 | err = perf_kprobe_init(event, is_retprobe); | |
9105 | if (err) | |
9106 | return err; | |
9107 | ||
9108 | event->destroy = perf_kprobe_destroy; | |
9109 | ||
9110 | return 0; | |
9111 | } | |
9112 | #endif /* CONFIG_KPROBE_EVENTS */ | |
9113 | ||
33ea4b24 | 9114 | #ifdef CONFIG_UPROBE_EVENTS |
a6ca88b2 SL |
9115 | PMU_FORMAT_ATTR(ref_ctr_offset, "config:32-63"); |
9116 | ||
9117 | static struct attribute *uprobe_attrs[] = { | |
9118 | &format_attr_retprobe.attr, | |
9119 | &format_attr_ref_ctr_offset.attr, | |
9120 | NULL, | |
9121 | }; | |
9122 | ||
9123 | static struct attribute_group uprobe_format_group = { | |
9124 | .name = "format", | |
9125 | .attrs = uprobe_attrs, | |
9126 | }; | |
9127 | ||
9128 | static const struct attribute_group *uprobe_attr_groups[] = { | |
9129 | &uprobe_format_group, | |
9130 | NULL, | |
9131 | }; | |
9132 | ||
33ea4b24 SL |
9133 | static int perf_uprobe_event_init(struct perf_event *event); |
9134 | static struct pmu perf_uprobe = { | |
9135 | .task_ctx_nr = perf_sw_context, | |
9136 | .event_init = perf_uprobe_event_init, | |
9137 | .add = perf_trace_add, | |
9138 | .del = perf_trace_del, | |
9139 | .start = perf_swevent_start, | |
9140 | .stop = perf_swevent_stop, | |
9141 | .read = perf_swevent_read, | |
a6ca88b2 | 9142 | .attr_groups = uprobe_attr_groups, |
33ea4b24 SL |
9143 | }; |
9144 | ||
9145 | static int perf_uprobe_event_init(struct perf_event *event) | |
9146 | { | |
9147 | int err; | |
a6ca88b2 | 9148 | unsigned long ref_ctr_offset; |
33ea4b24 SL |
9149 | bool is_retprobe; |
9150 | ||
9151 | if (event->attr.type != perf_uprobe.type) | |
9152 | return -ENOENT; | |
32e6e967 SL |
9153 | |
9154 | if (!capable(CAP_SYS_ADMIN)) | |
9155 | return -EACCES; | |
9156 | ||
33ea4b24 SL |
9157 | /* |
9158 | * no branch sampling for probe events | |
9159 | */ | |
9160 | if (has_branch_stack(event)) | |
9161 | return -EOPNOTSUPP; | |
9162 | ||
9163 | is_retprobe = event->attr.config & PERF_PROBE_CONFIG_IS_RETPROBE; | |
a6ca88b2 SL |
9164 | ref_ctr_offset = event->attr.config >> PERF_UPROBE_REF_CTR_OFFSET_SHIFT; |
9165 | err = perf_uprobe_init(event, ref_ctr_offset, is_retprobe); | |
33ea4b24 SL |
9166 | if (err) |
9167 | return err; | |
9168 | ||
9169 | event->destroy = perf_uprobe_destroy; | |
9170 | ||
9171 | return 0; | |
9172 | } | |
9173 | #endif /* CONFIG_UPROBE_EVENTS */ | |
9174 | ||
b0a873eb PZ |
9175 | static inline void perf_tp_register(void) |
9176 | { | |
2e80a82a | 9177 | perf_pmu_register(&perf_tracepoint, "tracepoint", PERF_TYPE_TRACEPOINT); |
e12f03d7 SL |
9178 | #ifdef CONFIG_KPROBE_EVENTS |
9179 | perf_pmu_register(&perf_kprobe, "kprobe", -1); | |
9180 | #endif | |
33ea4b24 SL |
9181 | #ifdef CONFIG_UPROBE_EVENTS |
9182 | perf_pmu_register(&perf_uprobe, "uprobe", -1); | |
9183 | #endif | |
e077df4f | 9184 | } |
6fb2915d | 9185 | |
6fb2915d LZ |
9186 | static void perf_event_free_filter(struct perf_event *event) |
9187 | { | |
9188 | ftrace_profile_free_filter(event); | |
9189 | } | |
9190 | ||
aa6a5f3c AS |
9191 | #ifdef CONFIG_BPF_SYSCALL |
9192 | static void bpf_overflow_handler(struct perf_event *event, | |
9193 | struct perf_sample_data *data, | |
9194 | struct pt_regs *regs) | |
9195 | { | |
9196 | struct bpf_perf_event_data_kern ctx = { | |
9197 | .data = data, | |
7d9285e8 | 9198 | .event = event, |
aa6a5f3c AS |
9199 | }; |
9200 | int ret = 0; | |
9201 | ||
c895f6f7 | 9202 | ctx.regs = perf_arch_bpf_user_pt_regs(regs); |
aa6a5f3c AS |
9203 | preempt_disable(); |
9204 | if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) | |
9205 | goto out; | |
9206 | rcu_read_lock(); | |
88575199 | 9207 | ret = BPF_PROG_RUN(event->prog, &ctx); |
aa6a5f3c AS |
9208 | rcu_read_unlock(); |
9209 | out: | |
9210 | __this_cpu_dec(bpf_prog_active); | |
9211 | preempt_enable(); | |
9212 | if (!ret) | |
9213 | return; | |
9214 | ||
9215 | event->orig_overflow_handler(event, data, regs); | |
9216 | } | |
9217 | ||
9218 | static int perf_event_set_bpf_handler(struct perf_event *event, u32 prog_fd) | |
9219 | { | |
9220 | struct bpf_prog *prog; | |
9221 | ||
9222 | if (event->overflow_handler_context) | |
9223 | /* hw breakpoint or kernel counter */ | |
9224 | return -EINVAL; | |
9225 | ||
9226 | if (event->prog) | |
9227 | return -EEXIST; | |
9228 | ||
9229 | prog = bpf_prog_get_type(prog_fd, BPF_PROG_TYPE_PERF_EVENT); | |
9230 | if (IS_ERR(prog)) | |
9231 | return PTR_ERR(prog); | |
9232 | ||
9233 | event->prog = prog; | |
9234 | event->orig_overflow_handler = READ_ONCE(event->overflow_handler); | |
9235 | WRITE_ONCE(event->overflow_handler, bpf_overflow_handler); | |
9236 | return 0; | |
9237 | } | |
9238 | ||
9239 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
9240 | { | |
9241 | struct bpf_prog *prog = event->prog; | |
9242 | ||
9243 | if (!prog) | |
9244 | return; | |
9245 | ||
9246 | WRITE_ONCE(event->overflow_handler, event->orig_overflow_handler); | |
9247 | event->prog = NULL; | |
9248 | bpf_prog_put(prog); | |
9249 | } | |
9250 | #else | |
9251 | static int perf_event_set_bpf_handler(struct perf_event *event, u32 prog_fd) | |
9252 | { | |
9253 | return -EOPNOTSUPP; | |
9254 | } | |
9255 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
9256 | { | |
9257 | } | |
9258 | #endif | |
9259 | ||
e12f03d7 SL |
9260 | /* |
9261 | * returns true if the event is a tracepoint, or a kprobe/upprobe created | |
9262 | * with perf_event_open() | |
9263 | */ | |
9264 | static inline bool perf_event_is_tracing(struct perf_event *event) | |
9265 | { | |
9266 | if (event->pmu == &perf_tracepoint) | |
9267 | return true; | |
9268 | #ifdef CONFIG_KPROBE_EVENTS | |
9269 | if (event->pmu == &perf_kprobe) | |
9270 | return true; | |
33ea4b24 SL |
9271 | #endif |
9272 | #ifdef CONFIG_UPROBE_EVENTS | |
9273 | if (event->pmu == &perf_uprobe) | |
9274 | return true; | |
e12f03d7 SL |
9275 | #endif |
9276 | return false; | |
9277 | } | |
9278 | ||
2541517c AS |
9279 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
9280 | { | |
cf5f5cea | 9281 | bool is_kprobe, is_tracepoint, is_syscall_tp; |
2541517c | 9282 | struct bpf_prog *prog; |
e87c6bc3 | 9283 | int ret; |
2541517c | 9284 | |
e12f03d7 | 9285 | if (!perf_event_is_tracing(event)) |
f91840a3 | 9286 | return perf_event_set_bpf_handler(event, prog_fd); |
2541517c | 9287 | |
98b5c2c6 AS |
9288 | is_kprobe = event->tp_event->flags & TRACE_EVENT_FL_UKPROBE; |
9289 | is_tracepoint = event->tp_event->flags & TRACE_EVENT_FL_TRACEPOINT; | |
cf5f5cea YS |
9290 | is_syscall_tp = is_syscall_trace_event(event->tp_event); |
9291 | if (!is_kprobe && !is_tracepoint && !is_syscall_tp) | |
98b5c2c6 | 9292 | /* bpf programs can only be attached to u/kprobe or tracepoint */ |
2541517c AS |
9293 | return -EINVAL; |
9294 | ||
9295 | prog = bpf_prog_get(prog_fd); | |
9296 | if (IS_ERR(prog)) | |
9297 | return PTR_ERR(prog); | |
9298 | ||
98b5c2c6 | 9299 | if ((is_kprobe && prog->type != BPF_PROG_TYPE_KPROBE) || |
cf5f5cea YS |
9300 | (is_tracepoint && prog->type != BPF_PROG_TYPE_TRACEPOINT) || |
9301 | (is_syscall_tp && prog->type != BPF_PROG_TYPE_TRACEPOINT)) { | |
2541517c AS |
9302 | /* valid fd, but invalid bpf program type */ |
9303 | bpf_prog_put(prog); | |
9304 | return -EINVAL; | |
9305 | } | |
9306 | ||
9802d865 JB |
9307 | /* Kprobe override only works for kprobes, not uprobes. */ |
9308 | if (prog->kprobe_override && | |
9309 | !(event->tp_event->flags & TRACE_EVENT_FL_KPROBE)) { | |
9310 | bpf_prog_put(prog); | |
9311 | return -EINVAL; | |
9312 | } | |
9313 | ||
cf5f5cea | 9314 | if (is_tracepoint || is_syscall_tp) { |
32bbe007 AS |
9315 | int off = trace_event_get_offsets(event->tp_event); |
9316 | ||
9317 | if (prog->aux->max_ctx_offset > off) { | |
9318 | bpf_prog_put(prog); | |
9319 | return -EACCES; | |
9320 | } | |
9321 | } | |
2541517c | 9322 | |
e87c6bc3 YS |
9323 | ret = perf_event_attach_bpf_prog(event, prog); |
9324 | if (ret) | |
9325 | bpf_prog_put(prog); | |
9326 | return ret; | |
2541517c AS |
9327 | } |
9328 | ||
9329 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
9330 | { | |
e12f03d7 | 9331 | if (!perf_event_is_tracing(event)) { |
0b4c6841 | 9332 | perf_event_free_bpf_handler(event); |
2541517c | 9333 | return; |
2541517c | 9334 | } |
e87c6bc3 | 9335 | perf_event_detach_bpf_prog(event); |
2541517c AS |
9336 | } |
9337 | ||
e077df4f | 9338 | #else |
6fb2915d | 9339 | |
b0a873eb | 9340 | static inline void perf_tp_register(void) |
e077df4f | 9341 | { |
e077df4f | 9342 | } |
6fb2915d | 9343 | |
6fb2915d LZ |
9344 | static void perf_event_free_filter(struct perf_event *event) |
9345 | { | |
9346 | } | |
9347 | ||
2541517c AS |
9348 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
9349 | { | |
9350 | return -ENOENT; | |
9351 | } | |
9352 | ||
9353 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
9354 | { | |
9355 | } | |
07b139c8 | 9356 | #endif /* CONFIG_EVENT_TRACING */ |
e077df4f | 9357 | |
24f1e32c | 9358 | #ifdef CONFIG_HAVE_HW_BREAKPOINT |
f5ffe02e | 9359 | void perf_bp_event(struct perf_event *bp, void *data) |
24f1e32c | 9360 | { |
f5ffe02e FW |
9361 | struct perf_sample_data sample; |
9362 | struct pt_regs *regs = data; | |
9363 | ||
fd0d000b | 9364 | perf_sample_data_init(&sample, bp->attr.bp_addr, 0); |
f5ffe02e | 9365 | |
a4eaf7f1 | 9366 | if (!bp->hw.state && !perf_exclude_event(bp, regs)) |
a8b0ca17 | 9367 | perf_swevent_event(bp, 1, &sample, regs); |
24f1e32c FW |
9368 | } |
9369 | #endif | |
9370 | ||
375637bc AS |
9371 | /* |
9372 | * Allocate a new address filter | |
9373 | */ | |
9374 | static struct perf_addr_filter * | |
9375 | perf_addr_filter_new(struct perf_event *event, struct list_head *filters) | |
9376 | { | |
9377 | int node = cpu_to_node(event->cpu == -1 ? 0 : event->cpu); | |
9378 | struct perf_addr_filter *filter; | |
9379 | ||
9380 | filter = kzalloc_node(sizeof(*filter), GFP_KERNEL, node); | |
9381 | if (!filter) | |
9382 | return NULL; | |
9383 | ||
9384 | INIT_LIST_HEAD(&filter->entry); | |
9385 | list_add_tail(&filter->entry, filters); | |
9386 | ||
9387 | return filter; | |
9388 | } | |
9389 | ||
9390 | static void free_filters_list(struct list_head *filters) | |
9391 | { | |
9392 | struct perf_addr_filter *filter, *iter; | |
9393 | ||
9394 | list_for_each_entry_safe(filter, iter, filters, entry) { | |
9511bce9 | 9395 | path_put(&filter->path); |
375637bc AS |
9396 | list_del(&filter->entry); |
9397 | kfree(filter); | |
9398 | } | |
9399 | } | |
9400 | ||
9401 | /* | |
9402 | * Free existing address filters and optionally install new ones | |
9403 | */ | |
9404 | static void perf_addr_filters_splice(struct perf_event *event, | |
9405 | struct list_head *head) | |
9406 | { | |
9407 | unsigned long flags; | |
9408 | LIST_HEAD(list); | |
9409 | ||
9410 | if (!has_addr_filter(event)) | |
9411 | return; | |
9412 | ||
9413 | /* don't bother with children, they don't have their own filters */ | |
9414 | if (event->parent) | |
9415 | return; | |
9416 | ||
9417 | raw_spin_lock_irqsave(&event->addr_filters.lock, flags); | |
9418 | ||
9419 | list_splice_init(&event->addr_filters.list, &list); | |
9420 | if (head) | |
9421 | list_splice(head, &event->addr_filters.list); | |
9422 | ||
9423 | raw_spin_unlock_irqrestore(&event->addr_filters.lock, flags); | |
9424 | ||
9425 | free_filters_list(&list); | |
9426 | } | |
9427 | ||
9428 | /* | |
9429 | * Scan through mm's vmas and see if one of them matches the | |
9430 | * @filter; if so, adjust filter's address range. | |
9431 | * Called with mm::mmap_sem down for reading. | |
9432 | */ | |
c60f83b8 AS |
9433 | static void perf_addr_filter_apply(struct perf_addr_filter *filter, |
9434 | struct mm_struct *mm, | |
9435 | struct perf_addr_filter_range *fr) | |
375637bc AS |
9436 | { |
9437 | struct vm_area_struct *vma; | |
9438 | ||
9439 | for (vma = mm->mmap; vma; vma = vma->vm_next) { | |
c60f83b8 | 9440 | if (!vma->vm_file) |
375637bc AS |
9441 | continue; |
9442 | ||
c60f83b8 AS |
9443 | if (perf_addr_filter_vma_adjust(filter, vma, fr)) |
9444 | return; | |
375637bc | 9445 | } |
375637bc AS |
9446 | } |
9447 | ||
9448 | /* | |
9449 | * Update event's address range filters based on the | |
9450 | * task's existing mappings, if any. | |
9451 | */ | |
9452 | static void perf_event_addr_filters_apply(struct perf_event *event) | |
9453 | { | |
9454 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
9455 | struct task_struct *task = READ_ONCE(event->ctx->task); | |
9456 | struct perf_addr_filter *filter; | |
9457 | struct mm_struct *mm = NULL; | |
9458 | unsigned int count = 0; | |
9459 | unsigned long flags; | |
9460 | ||
9461 | /* | |
9462 | * We may observe TASK_TOMBSTONE, which means that the event tear-down | |
9463 | * will stop on the parent's child_mutex that our caller is also holding | |
9464 | */ | |
9465 | if (task == TASK_TOMBSTONE) | |
9466 | return; | |
9467 | ||
52a44f83 AS |
9468 | if (ifh->nr_file_filters) { |
9469 | mm = get_task_mm(event->ctx->task); | |
9470 | if (!mm) | |
9471 | goto restart; | |
375637bc | 9472 | |
52a44f83 AS |
9473 | down_read(&mm->mmap_sem); |
9474 | } | |
375637bc AS |
9475 | |
9476 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
9477 | list_for_each_entry(filter, &ifh->list, entry) { | |
52a44f83 AS |
9478 | if (filter->path.dentry) { |
9479 | /* | |
9480 | * Adjust base offset if the filter is associated to a | |
9481 | * binary that needs to be mapped: | |
9482 | */ | |
9483 | event->addr_filter_ranges[count].start = 0; | |
9484 | event->addr_filter_ranges[count].size = 0; | |
375637bc | 9485 | |
c60f83b8 | 9486 | perf_addr_filter_apply(filter, mm, &event->addr_filter_ranges[count]); |
52a44f83 AS |
9487 | } else { |
9488 | event->addr_filter_ranges[count].start = filter->offset; | |
9489 | event->addr_filter_ranges[count].size = filter->size; | |
9490 | } | |
375637bc AS |
9491 | |
9492 | count++; | |
9493 | } | |
9494 | ||
9495 | event->addr_filters_gen++; | |
9496 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
9497 | ||
52a44f83 AS |
9498 | if (ifh->nr_file_filters) { |
9499 | up_read(&mm->mmap_sem); | |
375637bc | 9500 | |
52a44f83 AS |
9501 | mmput(mm); |
9502 | } | |
375637bc AS |
9503 | |
9504 | restart: | |
767ae086 | 9505 | perf_event_stop(event, 1); |
375637bc AS |
9506 | } |
9507 | ||
9508 | /* | |
9509 | * Address range filtering: limiting the data to certain | |
9510 | * instruction address ranges. Filters are ioctl()ed to us from | |
9511 | * userspace as ascii strings. | |
9512 | * | |
9513 | * Filter string format: | |
9514 | * | |
9515 | * ACTION RANGE_SPEC | |
9516 | * where ACTION is one of the | |
9517 | * * "filter": limit the trace to this region | |
9518 | * * "start": start tracing from this address | |
9519 | * * "stop": stop tracing at this address/region; | |
9520 | * RANGE_SPEC is | |
9521 | * * for kernel addresses: <start address>[/<size>] | |
9522 | * * for object files: <start address>[/<size>]@</path/to/object/file> | |
9523 | * | |
6ed70cf3 AS |
9524 | * if <size> is not specified or is zero, the range is treated as a single |
9525 | * address; not valid for ACTION=="filter". | |
375637bc AS |
9526 | */ |
9527 | enum { | |
e96271f3 | 9528 | IF_ACT_NONE = -1, |
375637bc AS |
9529 | IF_ACT_FILTER, |
9530 | IF_ACT_START, | |
9531 | IF_ACT_STOP, | |
9532 | IF_SRC_FILE, | |
9533 | IF_SRC_KERNEL, | |
9534 | IF_SRC_FILEADDR, | |
9535 | IF_SRC_KERNELADDR, | |
9536 | }; | |
9537 | ||
9538 | enum { | |
9539 | IF_STATE_ACTION = 0, | |
9540 | IF_STATE_SOURCE, | |
9541 | IF_STATE_END, | |
9542 | }; | |
9543 | ||
9544 | static const match_table_t if_tokens = { | |
9545 | { IF_ACT_FILTER, "filter" }, | |
9546 | { IF_ACT_START, "start" }, | |
9547 | { IF_ACT_STOP, "stop" }, | |
9548 | { IF_SRC_FILE, "%u/%u@%s" }, | |
9549 | { IF_SRC_KERNEL, "%u/%u" }, | |
9550 | { IF_SRC_FILEADDR, "%u@%s" }, | |
9551 | { IF_SRC_KERNELADDR, "%u" }, | |
e96271f3 | 9552 | { IF_ACT_NONE, NULL }, |
375637bc AS |
9553 | }; |
9554 | ||
9555 | /* | |
9556 | * Address filter string parser | |
9557 | */ | |
9558 | static int | |
9559 | perf_event_parse_addr_filter(struct perf_event *event, char *fstr, | |
9560 | struct list_head *filters) | |
9561 | { | |
9562 | struct perf_addr_filter *filter = NULL; | |
9563 | char *start, *orig, *filename = NULL; | |
375637bc AS |
9564 | substring_t args[MAX_OPT_ARGS]; |
9565 | int state = IF_STATE_ACTION, token; | |
9566 | unsigned int kernel = 0; | |
9567 | int ret = -EINVAL; | |
9568 | ||
9569 | orig = fstr = kstrdup(fstr, GFP_KERNEL); | |
9570 | if (!fstr) | |
9571 | return -ENOMEM; | |
9572 | ||
9573 | while ((start = strsep(&fstr, " ,\n")) != NULL) { | |
6ed70cf3 AS |
9574 | static const enum perf_addr_filter_action_t actions[] = { |
9575 | [IF_ACT_FILTER] = PERF_ADDR_FILTER_ACTION_FILTER, | |
9576 | [IF_ACT_START] = PERF_ADDR_FILTER_ACTION_START, | |
9577 | [IF_ACT_STOP] = PERF_ADDR_FILTER_ACTION_STOP, | |
9578 | }; | |
375637bc AS |
9579 | ret = -EINVAL; |
9580 | ||
9581 | if (!*start) | |
9582 | continue; | |
9583 | ||
9584 | /* filter definition begins */ | |
9585 | if (state == IF_STATE_ACTION) { | |
9586 | filter = perf_addr_filter_new(event, filters); | |
9587 | if (!filter) | |
9588 | goto fail; | |
9589 | } | |
9590 | ||
9591 | token = match_token(start, if_tokens, args); | |
9592 | switch (token) { | |
9593 | case IF_ACT_FILTER: | |
9594 | case IF_ACT_START: | |
375637bc AS |
9595 | case IF_ACT_STOP: |
9596 | if (state != IF_STATE_ACTION) | |
9597 | goto fail; | |
9598 | ||
6ed70cf3 | 9599 | filter->action = actions[token]; |
375637bc AS |
9600 | state = IF_STATE_SOURCE; |
9601 | break; | |
9602 | ||
9603 | case IF_SRC_KERNELADDR: | |
9604 | case IF_SRC_KERNEL: | |
9605 | kernel = 1; | |
10c3405f | 9606 | /* fall through */ |
375637bc AS |
9607 | |
9608 | case IF_SRC_FILEADDR: | |
9609 | case IF_SRC_FILE: | |
9610 | if (state != IF_STATE_SOURCE) | |
9611 | goto fail; | |
9612 | ||
375637bc AS |
9613 | *args[0].to = 0; |
9614 | ret = kstrtoul(args[0].from, 0, &filter->offset); | |
9615 | if (ret) | |
9616 | goto fail; | |
9617 | ||
6ed70cf3 | 9618 | if (token == IF_SRC_KERNEL || token == IF_SRC_FILE) { |
375637bc AS |
9619 | *args[1].to = 0; |
9620 | ret = kstrtoul(args[1].from, 0, &filter->size); | |
9621 | if (ret) | |
9622 | goto fail; | |
9623 | } | |
9624 | ||
4059ffd0 | 9625 | if (token == IF_SRC_FILE || token == IF_SRC_FILEADDR) { |
6ed70cf3 | 9626 | int fpos = token == IF_SRC_FILE ? 2 : 1; |
4059ffd0 MP |
9627 | |
9628 | filename = match_strdup(&args[fpos]); | |
375637bc AS |
9629 | if (!filename) { |
9630 | ret = -ENOMEM; | |
9631 | goto fail; | |
9632 | } | |
9633 | } | |
9634 | ||
9635 | state = IF_STATE_END; | |
9636 | break; | |
9637 | ||
9638 | default: | |
9639 | goto fail; | |
9640 | } | |
9641 | ||
9642 | /* | |
9643 | * Filter definition is fully parsed, validate and install it. | |
9644 | * Make sure that it doesn't contradict itself or the event's | |
9645 | * attribute. | |
9646 | */ | |
9647 | if (state == IF_STATE_END) { | |
9ccbfbb1 | 9648 | ret = -EINVAL; |
375637bc AS |
9649 | if (kernel && event->attr.exclude_kernel) |
9650 | goto fail; | |
9651 | ||
6ed70cf3 AS |
9652 | /* |
9653 | * ACTION "filter" must have a non-zero length region | |
9654 | * specified. | |
9655 | */ | |
9656 | if (filter->action == PERF_ADDR_FILTER_ACTION_FILTER && | |
9657 | !filter->size) | |
9658 | goto fail; | |
9659 | ||
375637bc AS |
9660 | if (!kernel) { |
9661 | if (!filename) | |
9662 | goto fail; | |
9663 | ||
6ce77bfd AS |
9664 | /* |
9665 | * For now, we only support file-based filters | |
9666 | * in per-task events; doing so for CPU-wide | |
9667 | * events requires additional context switching | |
9668 | * trickery, since same object code will be | |
9669 | * mapped at different virtual addresses in | |
9670 | * different processes. | |
9671 | */ | |
9672 | ret = -EOPNOTSUPP; | |
9673 | if (!event->ctx->task) | |
9674 | goto fail_free_name; | |
9675 | ||
375637bc | 9676 | /* look up the path and grab its inode */ |
9511bce9 SL |
9677 | ret = kern_path(filename, LOOKUP_FOLLOW, |
9678 | &filter->path); | |
375637bc AS |
9679 | if (ret) |
9680 | goto fail_free_name; | |
9681 | ||
375637bc AS |
9682 | kfree(filename); |
9683 | filename = NULL; | |
9684 | ||
9685 | ret = -EINVAL; | |
9511bce9 SL |
9686 | if (!filter->path.dentry || |
9687 | !S_ISREG(d_inode(filter->path.dentry) | |
9688 | ->i_mode)) | |
375637bc | 9689 | goto fail; |
6ce77bfd AS |
9690 | |
9691 | event->addr_filters.nr_file_filters++; | |
375637bc AS |
9692 | } |
9693 | ||
9694 | /* ready to consume more filters */ | |
9695 | state = IF_STATE_ACTION; | |
9696 | filter = NULL; | |
9697 | } | |
9698 | } | |
9699 | ||
9700 | if (state != IF_STATE_ACTION) | |
9701 | goto fail; | |
9702 | ||
9703 | kfree(orig); | |
9704 | ||
9705 | return 0; | |
9706 | ||
9707 | fail_free_name: | |
9708 | kfree(filename); | |
9709 | fail: | |
9710 | free_filters_list(filters); | |
9711 | kfree(orig); | |
9712 | ||
9713 | return ret; | |
9714 | } | |
9715 | ||
9716 | static int | |
9717 | perf_event_set_addr_filter(struct perf_event *event, char *filter_str) | |
9718 | { | |
9719 | LIST_HEAD(filters); | |
9720 | int ret; | |
9721 | ||
9722 | /* | |
9723 | * Since this is called in perf_ioctl() path, we're already holding | |
9724 | * ctx::mutex. | |
9725 | */ | |
9726 | lockdep_assert_held(&event->ctx->mutex); | |
9727 | ||
9728 | if (WARN_ON_ONCE(event->parent)) | |
9729 | return -EINVAL; | |
9730 | ||
375637bc AS |
9731 | ret = perf_event_parse_addr_filter(event, filter_str, &filters); |
9732 | if (ret) | |
6ce77bfd | 9733 | goto fail_clear_files; |
375637bc AS |
9734 | |
9735 | ret = event->pmu->addr_filters_validate(&filters); | |
6ce77bfd AS |
9736 | if (ret) |
9737 | goto fail_free_filters; | |
375637bc AS |
9738 | |
9739 | /* remove existing filters, if any */ | |
9740 | perf_addr_filters_splice(event, &filters); | |
9741 | ||
9742 | /* install new filters */ | |
9743 | perf_event_for_each_child(event, perf_event_addr_filters_apply); | |
9744 | ||
6ce77bfd AS |
9745 | return ret; |
9746 | ||
9747 | fail_free_filters: | |
9748 | free_filters_list(&filters); | |
9749 | ||
9750 | fail_clear_files: | |
9751 | event->addr_filters.nr_file_filters = 0; | |
9752 | ||
375637bc AS |
9753 | return ret; |
9754 | } | |
9755 | ||
c796bbbe AS |
9756 | static int perf_event_set_filter(struct perf_event *event, void __user *arg) |
9757 | { | |
c796bbbe | 9758 | int ret = -EINVAL; |
e12f03d7 | 9759 | char *filter_str; |
c796bbbe AS |
9760 | |
9761 | filter_str = strndup_user(arg, PAGE_SIZE); | |
9762 | if (IS_ERR(filter_str)) | |
9763 | return PTR_ERR(filter_str); | |
9764 | ||
e12f03d7 SL |
9765 | #ifdef CONFIG_EVENT_TRACING |
9766 | if (perf_event_is_tracing(event)) { | |
9767 | struct perf_event_context *ctx = event->ctx; | |
9768 | ||
9769 | /* | |
9770 | * Beware, here be dragons!! | |
9771 | * | |
9772 | * the tracepoint muck will deadlock against ctx->mutex, but | |
9773 | * the tracepoint stuff does not actually need it. So | |
9774 | * temporarily drop ctx->mutex. As per perf_event_ctx_lock() we | |
9775 | * already have a reference on ctx. | |
9776 | * | |
9777 | * This can result in event getting moved to a different ctx, | |
9778 | * but that does not affect the tracepoint state. | |
9779 | */ | |
9780 | mutex_unlock(&ctx->mutex); | |
9781 | ret = ftrace_profile_set_filter(event, event->attr.config, filter_str); | |
9782 | mutex_lock(&ctx->mutex); | |
9783 | } else | |
9784 | #endif | |
9785 | if (has_addr_filter(event)) | |
375637bc | 9786 | ret = perf_event_set_addr_filter(event, filter_str); |
c796bbbe AS |
9787 | |
9788 | kfree(filter_str); | |
9789 | return ret; | |
9790 | } | |
9791 | ||
b0a873eb PZ |
9792 | /* |
9793 | * hrtimer based swevent callback | |
9794 | */ | |
f29ac756 | 9795 | |
b0a873eb | 9796 | static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer) |
f29ac756 | 9797 | { |
b0a873eb PZ |
9798 | enum hrtimer_restart ret = HRTIMER_RESTART; |
9799 | struct perf_sample_data data; | |
9800 | struct pt_regs *regs; | |
9801 | struct perf_event *event; | |
9802 | u64 period; | |
f29ac756 | 9803 | |
b0a873eb | 9804 | event = container_of(hrtimer, struct perf_event, hw.hrtimer); |
ba3dd36c PZ |
9805 | |
9806 | if (event->state != PERF_EVENT_STATE_ACTIVE) | |
9807 | return HRTIMER_NORESTART; | |
9808 | ||
b0a873eb | 9809 | event->pmu->read(event); |
f344011c | 9810 | |
fd0d000b | 9811 | perf_sample_data_init(&data, 0, event->hw.last_period); |
b0a873eb PZ |
9812 | regs = get_irq_regs(); |
9813 | ||
9814 | if (regs && !perf_exclude_event(event, regs)) { | |
77aeeebd | 9815 | if (!(event->attr.exclude_idle && is_idle_task(current))) |
33b07b8b | 9816 | if (__perf_event_overflow(event, 1, &data, regs)) |
b0a873eb PZ |
9817 | ret = HRTIMER_NORESTART; |
9818 | } | |
24f1e32c | 9819 | |
b0a873eb PZ |
9820 | period = max_t(u64, 10000, event->hw.sample_period); |
9821 | hrtimer_forward_now(hrtimer, ns_to_ktime(period)); | |
24f1e32c | 9822 | |
b0a873eb | 9823 | return ret; |
f29ac756 PZ |
9824 | } |
9825 | ||
b0a873eb | 9826 | static void perf_swevent_start_hrtimer(struct perf_event *event) |
5c92d124 | 9827 | { |
b0a873eb | 9828 | struct hw_perf_event *hwc = &event->hw; |
5d508e82 FBH |
9829 | s64 period; |
9830 | ||
9831 | if (!is_sampling_event(event)) | |
9832 | return; | |
f5ffe02e | 9833 | |
5d508e82 FBH |
9834 | period = local64_read(&hwc->period_left); |
9835 | if (period) { | |
9836 | if (period < 0) | |
9837 | period = 10000; | |
fa407f35 | 9838 | |
5d508e82 FBH |
9839 | local64_set(&hwc->period_left, 0); |
9840 | } else { | |
9841 | period = max_t(u64, 10000, hwc->sample_period); | |
9842 | } | |
3497d206 | 9843 | hrtimer_start(&hwc->hrtimer, ns_to_ktime(period), |
30f9028b | 9844 | HRTIMER_MODE_REL_PINNED_HARD); |
24f1e32c | 9845 | } |
b0a873eb PZ |
9846 | |
9847 | static void perf_swevent_cancel_hrtimer(struct perf_event *event) | |
24f1e32c | 9848 | { |
b0a873eb PZ |
9849 | struct hw_perf_event *hwc = &event->hw; |
9850 | ||
6c7e550f | 9851 | if (is_sampling_event(event)) { |
b0a873eb | 9852 | ktime_t remaining = hrtimer_get_remaining(&hwc->hrtimer); |
fa407f35 | 9853 | local64_set(&hwc->period_left, ktime_to_ns(remaining)); |
b0a873eb PZ |
9854 | |
9855 | hrtimer_cancel(&hwc->hrtimer); | |
9856 | } | |
24f1e32c FW |
9857 | } |
9858 | ||
ba3dd36c PZ |
9859 | static void perf_swevent_init_hrtimer(struct perf_event *event) |
9860 | { | |
9861 | struct hw_perf_event *hwc = &event->hw; | |
9862 | ||
9863 | if (!is_sampling_event(event)) | |
9864 | return; | |
9865 | ||
30f9028b | 9866 | hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_HARD); |
ba3dd36c PZ |
9867 | hwc->hrtimer.function = perf_swevent_hrtimer; |
9868 | ||
9869 | /* | |
9870 | * Since hrtimers have a fixed rate, we can do a static freq->period | |
9871 | * mapping and avoid the whole period adjust feedback stuff. | |
9872 | */ | |
9873 | if (event->attr.freq) { | |
9874 | long freq = event->attr.sample_freq; | |
9875 | ||
9876 | event->attr.sample_period = NSEC_PER_SEC / freq; | |
9877 | hwc->sample_period = event->attr.sample_period; | |
9878 | local64_set(&hwc->period_left, hwc->sample_period); | |
778141e3 | 9879 | hwc->last_period = hwc->sample_period; |
ba3dd36c PZ |
9880 | event->attr.freq = 0; |
9881 | } | |
9882 | } | |
9883 | ||
b0a873eb PZ |
9884 | /* |
9885 | * Software event: cpu wall time clock | |
9886 | */ | |
9887 | ||
9888 | static void cpu_clock_event_update(struct perf_event *event) | |
24f1e32c | 9889 | { |
b0a873eb PZ |
9890 | s64 prev; |
9891 | u64 now; | |
9892 | ||
a4eaf7f1 | 9893 | now = local_clock(); |
b0a873eb PZ |
9894 | prev = local64_xchg(&event->hw.prev_count, now); |
9895 | local64_add(now - prev, &event->count); | |
24f1e32c | 9896 | } |
24f1e32c | 9897 | |
a4eaf7f1 | 9898 | static void cpu_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 9899 | { |
a4eaf7f1 | 9900 | local64_set(&event->hw.prev_count, local_clock()); |
b0a873eb | 9901 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
9902 | } |
9903 | ||
a4eaf7f1 | 9904 | static void cpu_clock_event_stop(struct perf_event *event, int flags) |
f29ac756 | 9905 | { |
b0a873eb PZ |
9906 | perf_swevent_cancel_hrtimer(event); |
9907 | cpu_clock_event_update(event); | |
9908 | } | |
f29ac756 | 9909 | |
a4eaf7f1 PZ |
9910 | static int cpu_clock_event_add(struct perf_event *event, int flags) |
9911 | { | |
9912 | if (flags & PERF_EF_START) | |
9913 | cpu_clock_event_start(event, flags); | |
6a694a60 | 9914 | perf_event_update_userpage(event); |
a4eaf7f1 PZ |
9915 | |
9916 | return 0; | |
9917 | } | |
9918 | ||
9919 | static void cpu_clock_event_del(struct perf_event *event, int flags) | |
9920 | { | |
9921 | cpu_clock_event_stop(event, flags); | |
9922 | } | |
9923 | ||
b0a873eb PZ |
9924 | static void cpu_clock_event_read(struct perf_event *event) |
9925 | { | |
9926 | cpu_clock_event_update(event); | |
9927 | } | |
f344011c | 9928 | |
b0a873eb PZ |
9929 | static int cpu_clock_event_init(struct perf_event *event) |
9930 | { | |
9931 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
9932 | return -ENOENT; | |
9933 | ||
9934 | if (event->attr.config != PERF_COUNT_SW_CPU_CLOCK) | |
9935 | return -ENOENT; | |
9936 | ||
2481c5fa SE |
9937 | /* |
9938 | * no branch sampling for software events | |
9939 | */ | |
9940 | if (has_branch_stack(event)) | |
9941 | return -EOPNOTSUPP; | |
9942 | ||
ba3dd36c PZ |
9943 | perf_swevent_init_hrtimer(event); |
9944 | ||
b0a873eb | 9945 | return 0; |
f29ac756 PZ |
9946 | } |
9947 | ||
b0a873eb | 9948 | static struct pmu perf_cpu_clock = { |
89a1e187 PZ |
9949 | .task_ctx_nr = perf_sw_context, |
9950 | ||
34f43927 PZ |
9951 | .capabilities = PERF_PMU_CAP_NO_NMI, |
9952 | ||
b0a873eb | 9953 | .event_init = cpu_clock_event_init, |
a4eaf7f1 PZ |
9954 | .add = cpu_clock_event_add, |
9955 | .del = cpu_clock_event_del, | |
9956 | .start = cpu_clock_event_start, | |
9957 | .stop = cpu_clock_event_stop, | |
b0a873eb PZ |
9958 | .read = cpu_clock_event_read, |
9959 | }; | |
9960 | ||
9961 | /* | |
9962 | * Software event: task time clock | |
9963 | */ | |
9964 | ||
9965 | static void task_clock_event_update(struct perf_event *event, u64 now) | |
5c92d124 | 9966 | { |
b0a873eb PZ |
9967 | u64 prev; |
9968 | s64 delta; | |
5c92d124 | 9969 | |
b0a873eb PZ |
9970 | prev = local64_xchg(&event->hw.prev_count, now); |
9971 | delta = now - prev; | |
9972 | local64_add(delta, &event->count); | |
9973 | } | |
5c92d124 | 9974 | |
a4eaf7f1 | 9975 | static void task_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 9976 | { |
a4eaf7f1 | 9977 | local64_set(&event->hw.prev_count, event->ctx->time); |
b0a873eb | 9978 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
9979 | } |
9980 | ||
a4eaf7f1 | 9981 | static void task_clock_event_stop(struct perf_event *event, int flags) |
b0a873eb PZ |
9982 | { |
9983 | perf_swevent_cancel_hrtimer(event); | |
9984 | task_clock_event_update(event, event->ctx->time); | |
a4eaf7f1 PZ |
9985 | } |
9986 | ||
9987 | static int task_clock_event_add(struct perf_event *event, int flags) | |
9988 | { | |
9989 | if (flags & PERF_EF_START) | |
9990 | task_clock_event_start(event, flags); | |
6a694a60 | 9991 | perf_event_update_userpage(event); |
b0a873eb | 9992 | |
a4eaf7f1 PZ |
9993 | return 0; |
9994 | } | |
9995 | ||
9996 | static void task_clock_event_del(struct perf_event *event, int flags) | |
9997 | { | |
9998 | task_clock_event_stop(event, PERF_EF_UPDATE); | |
b0a873eb PZ |
9999 | } |
10000 | ||
10001 | static void task_clock_event_read(struct perf_event *event) | |
10002 | { | |
768a06e2 PZ |
10003 | u64 now = perf_clock(); |
10004 | u64 delta = now - event->ctx->timestamp; | |
10005 | u64 time = event->ctx->time + delta; | |
b0a873eb PZ |
10006 | |
10007 | task_clock_event_update(event, time); | |
10008 | } | |
10009 | ||
10010 | static int task_clock_event_init(struct perf_event *event) | |
6fb2915d | 10011 | { |
b0a873eb PZ |
10012 | if (event->attr.type != PERF_TYPE_SOFTWARE) |
10013 | return -ENOENT; | |
10014 | ||
10015 | if (event->attr.config != PERF_COUNT_SW_TASK_CLOCK) | |
10016 | return -ENOENT; | |
10017 | ||
2481c5fa SE |
10018 | /* |
10019 | * no branch sampling for software events | |
10020 | */ | |
10021 | if (has_branch_stack(event)) | |
10022 | return -EOPNOTSUPP; | |
10023 | ||
ba3dd36c PZ |
10024 | perf_swevent_init_hrtimer(event); |
10025 | ||
b0a873eb | 10026 | return 0; |
6fb2915d LZ |
10027 | } |
10028 | ||
b0a873eb | 10029 | static struct pmu perf_task_clock = { |
89a1e187 PZ |
10030 | .task_ctx_nr = perf_sw_context, |
10031 | ||
34f43927 PZ |
10032 | .capabilities = PERF_PMU_CAP_NO_NMI, |
10033 | ||
b0a873eb | 10034 | .event_init = task_clock_event_init, |
a4eaf7f1 PZ |
10035 | .add = task_clock_event_add, |
10036 | .del = task_clock_event_del, | |
10037 | .start = task_clock_event_start, | |
10038 | .stop = task_clock_event_stop, | |
b0a873eb PZ |
10039 | .read = task_clock_event_read, |
10040 | }; | |
6fb2915d | 10041 | |
ad5133b7 | 10042 | static void perf_pmu_nop_void(struct pmu *pmu) |
e077df4f | 10043 | { |
e077df4f | 10044 | } |
6fb2915d | 10045 | |
fbbe0701 SB |
10046 | static void perf_pmu_nop_txn(struct pmu *pmu, unsigned int flags) |
10047 | { | |
10048 | } | |
10049 | ||
ad5133b7 | 10050 | static int perf_pmu_nop_int(struct pmu *pmu) |
6fb2915d | 10051 | { |
ad5133b7 | 10052 | return 0; |
6fb2915d LZ |
10053 | } |
10054 | ||
81ec3f3c JO |
10055 | static int perf_event_nop_int(struct perf_event *event, u64 value) |
10056 | { | |
10057 | return 0; | |
10058 | } | |
10059 | ||
18ab2cd3 | 10060 | static DEFINE_PER_CPU(unsigned int, nop_txn_flags); |
fbbe0701 SB |
10061 | |
10062 | static void perf_pmu_start_txn(struct pmu *pmu, unsigned int flags) | |
6fb2915d | 10063 | { |
fbbe0701 SB |
10064 | __this_cpu_write(nop_txn_flags, flags); |
10065 | ||
10066 | if (flags & ~PERF_PMU_TXN_ADD) | |
10067 | return; | |
10068 | ||
ad5133b7 | 10069 | perf_pmu_disable(pmu); |
6fb2915d LZ |
10070 | } |
10071 | ||
ad5133b7 PZ |
10072 | static int perf_pmu_commit_txn(struct pmu *pmu) |
10073 | { | |
fbbe0701 SB |
10074 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
10075 | ||
10076 | __this_cpu_write(nop_txn_flags, 0); | |
10077 | ||
10078 | if (flags & ~PERF_PMU_TXN_ADD) | |
10079 | return 0; | |
10080 | ||
ad5133b7 PZ |
10081 | perf_pmu_enable(pmu); |
10082 | return 0; | |
10083 | } | |
e077df4f | 10084 | |
ad5133b7 | 10085 | static void perf_pmu_cancel_txn(struct pmu *pmu) |
24f1e32c | 10086 | { |
fbbe0701 SB |
10087 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
10088 | ||
10089 | __this_cpu_write(nop_txn_flags, 0); | |
10090 | ||
10091 | if (flags & ~PERF_PMU_TXN_ADD) | |
10092 | return; | |
10093 | ||
ad5133b7 | 10094 | perf_pmu_enable(pmu); |
24f1e32c FW |
10095 | } |
10096 | ||
35edc2a5 PZ |
10097 | static int perf_event_idx_default(struct perf_event *event) |
10098 | { | |
c719f560 | 10099 | return 0; |
35edc2a5 PZ |
10100 | } |
10101 | ||
8dc85d54 PZ |
10102 | /* |
10103 | * Ensures all contexts with the same task_ctx_nr have the same | |
10104 | * pmu_cpu_context too. | |
10105 | */ | |
9e317041 | 10106 | static struct perf_cpu_context __percpu *find_pmu_context(int ctxn) |
24f1e32c | 10107 | { |
8dc85d54 | 10108 | struct pmu *pmu; |
b326e956 | 10109 | |
8dc85d54 PZ |
10110 | if (ctxn < 0) |
10111 | return NULL; | |
24f1e32c | 10112 | |
8dc85d54 PZ |
10113 | list_for_each_entry(pmu, &pmus, entry) { |
10114 | if (pmu->task_ctx_nr == ctxn) | |
10115 | return pmu->pmu_cpu_context; | |
10116 | } | |
24f1e32c | 10117 | |
8dc85d54 | 10118 | return NULL; |
24f1e32c FW |
10119 | } |
10120 | ||
51676957 PZ |
10121 | static void free_pmu_context(struct pmu *pmu) |
10122 | { | |
df0062b2 WD |
10123 | /* |
10124 | * Static contexts such as perf_sw_context have a global lifetime | |
10125 | * and may be shared between different PMUs. Avoid freeing them | |
10126 | * when a single PMU is going away. | |
10127 | */ | |
10128 | if (pmu->task_ctx_nr > perf_invalid_context) | |
10129 | return; | |
10130 | ||
51676957 | 10131 | free_percpu(pmu->pmu_cpu_context); |
24f1e32c | 10132 | } |
6e855cd4 AS |
10133 | |
10134 | /* | |
10135 | * Let userspace know that this PMU supports address range filtering: | |
10136 | */ | |
10137 | static ssize_t nr_addr_filters_show(struct device *dev, | |
10138 | struct device_attribute *attr, | |
10139 | char *page) | |
10140 | { | |
10141 | struct pmu *pmu = dev_get_drvdata(dev); | |
10142 | ||
10143 | return snprintf(page, PAGE_SIZE - 1, "%d\n", pmu->nr_addr_filters); | |
10144 | } | |
10145 | DEVICE_ATTR_RO(nr_addr_filters); | |
10146 | ||
2e80a82a | 10147 | static struct idr pmu_idr; |
d6d020e9 | 10148 | |
abe43400 PZ |
10149 | static ssize_t |
10150 | type_show(struct device *dev, struct device_attribute *attr, char *page) | |
10151 | { | |
10152 | struct pmu *pmu = dev_get_drvdata(dev); | |
10153 | ||
10154 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->type); | |
10155 | } | |
90826ca7 | 10156 | static DEVICE_ATTR_RO(type); |
abe43400 | 10157 | |
62b85639 SE |
10158 | static ssize_t |
10159 | perf_event_mux_interval_ms_show(struct device *dev, | |
10160 | struct device_attribute *attr, | |
10161 | char *page) | |
10162 | { | |
10163 | struct pmu *pmu = dev_get_drvdata(dev); | |
10164 | ||
10165 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->hrtimer_interval_ms); | |
10166 | } | |
10167 | ||
272325c4 PZ |
10168 | static DEFINE_MUTEX(mux_interval_mutex); |
10169 | ||
62b85639 SE |
10170 | static ssize_t |
10171 | perf_event_mux_interval_ms_store(struct device *dev, | |
10172 | struct device_attribute *attr, | |
10173 | const char *buf, size_t count) | |
10174 | { | |
10175 | struct pmu *pmu = dev_get_drvdata(dev); | |
10176 | int timer, cpu, ret; | |
10177 | ||
10178 | ret = kstrtoint(buf, 0, &timer); | |
10179 | if (ret) | |
10180 | return ret; | |
10181 | ||
10182 | if (timer < 1) | |
10183 | return -EINVAL; | |
10184 | ||
10185 | /* same value, noting to do */ | |
10186 | if (timer == pmu->hrtimer_interval_ms) | |
10187 | return count; | |
10188 | ||
272325c4 | 10189 | mutex_lock(&mux_interval_mutex); |
62b85639 SE |
10190 | pmu->hrtimer_interval_ms = timer; |
10191 | ||
10192 | /* update all cpuctx for this PMU */ | |
a63fbed7 | 10193 | cpus_read_lock(); |
272325c4 | 10194 | for_each_online_cpu(cpu) { |
62b85639 SE |
10195 | struct perf_cpu_context *cpuctx; |
10196 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
10197 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * timer); | |
10198 | ||
272325c4 PZ |
10199 | cpu_function_call(cpu, |
10200 | (remote_function_f)perf_mux_hrtimer_restart, cpuctx); | |
62b85639 | 10201 | } |
a63fbed7 | 10202 | cpus_read_unlock(); |
272325c4 | 10203 | mutex_unlock(&mux_interval_mutex); |
62b85639 SE |
10204 | |
10205 | return count; | |
10206 | } | |
90826ca7 | 10207 | static DEVICE_ATTR_RW(perf_event_mux_interval_ms); |
62b85639 | 10208 | |
90826ca7 GKH |
10209 | static struct attribute *pmu_dev_attrs[] = { |
10210 | &dev_attr_type.attr, | |
10211 | &dev_attr_perf_event_mux_interval_ms.attr, | |
10212 | NULL, | |
abe43400 | 10213 | }; |
90826ca7 | 10214 | ATTRIBUTE_GROUPS(pmu_dev); |
abe43400 PZ |
10215 | |
10216 | static int pmu_bus_running; | |
10217 | static struct bus_type pmu_bus = { | |
10218 | .name = "event_source", | |
90826ca7 | 10219 | .dev_groups = pmu_dev_groups, |
abe43400 PZ |
10220 | }; |
10221 | ||
10222 | static void pmu_dev_release(struct device *dev) | |
10223 | { | |
10224 | kfree(dev); | |
10225 | } | |
10226 | ||
10227 | static int pmu_dev_alloc(struct pmu *pmu) | |
10228 | { | |
10229 | int ret = -ENOMEM; | |
10230 | ||
10231 | pmu->dev = kzalloc(sizeof(struct device), GFP_KERNEL); | |
10232 | if (!pmu->dev) | |
10233 | goto out; | |
10234 | ||
0c9d42ed | 10235 | pmu->dev->groups = pmu->attr_groups; |
abe43400 PZ |
10236 | device_initialize(pmu->dev); |
10237 | ret = dev_set_name(pmu->dev, "%s", pmu->name); | |
10238 | if (ret) | |
10239 | goto free_dev; | |
10240 | ||
10241 | dev_set_drvdata(pmu->dev, pmu); | |
10242 | pmu->dev->bus = &pmu_bus; | |
10243 | pmu->dev->release = pmu_dev_release; | |
10244 | ret = device_add(pmu->dev); | |
10245 | if (ret) | |
10246 | goto free_dev; | |
10247 | ||
6e855cd4 AS |
10248 | /* For PMUs with address filters, throw in an extra attribute: */ |
10249 | if (pmu->nr_addr_filters) | |
10250 | ret = device_create_file(pmu->dev, &dev_attr_nr_addr_filters); | |
10251 | ||
10252 | if (ret) | |
10253 | goto del_dev; | |
10254 | ||
f3a3a825 JO |
10255 | if (pmu->attr_update) |
10256 | ret = sysfs_update_groups(&pmu->dev->kobj, pmu->attr_update); | |
10257 | ||
10258 | if (ret) | |
10259 | goto del_dev; | |
10260 | ||
abe43400 PZ |
10261 | out: |
10262 | return ret; | |
10263 | ||
6e855cd4 AS |
10264 | del_dev: |
10265 | device_del(pmu->dev); | |
10266 | ||
abe43400 PZ |
10267 | free_dev: |
10268 | put_device(pmu->dev); | |
10269 | goto out; | |
10270 | } | |
10271 | ||
547e9fd7 | 10272 | static struct lock_class_key cpuctx_mutex; |
facc4307 | 10273 | static struct lock_class_key cpuctx_lock; |
547e9fd7 | 10274 | |
03d8e80b | 10275 | int perf_pmu_register(struct pmu *pmu, const char *name, int type) |
24f1e32c | 10276 | { |
66d258c5 | 10277 | int cpu, ret, max = PERF_TYPE_MAX; |
24f1e32c | 10278 | |
b0a873eb | 10279 | mutex_lock(&pmus_lock); |
33696fc0 PZ |
10280 | ret = -ENOMEM; |
10281 | pmu->pmu_disable_count = alloc_percpu(int); | |
10282 | if (!pmu->pmu_disable_count) | |
10283 | goto unlock; | |
f29ac756 | 10284 | |
2e80a82a PZ |
10285 | pmu->type = -1; |
10286 | if (!name) | |
10287 | goto skip_type; | |
10288 | pmu->name = name; | |
10289 | ||
66d258c5 PZ |
10290 | if (type != PERF_TYPE_SOFTWARE) { |
10291 | if (type >= 0) | |
10292 | max = type; | |
10293 | ||
10294 | ret = idr_alloc(&pmu_idr, pmu, max, 0, GFP_KERNEL); | |
10295 | if (ret < 0) | |
2e80a82a | 10296 | goto free_pdc; |
66d258c5 PZ |
10297 | |
10298 | WARN_ON(type >= 0 && ret != type); | |
10299 | ||
10300 | type = ret; | |
2e80a82a PZ |
10301 | } |
10302 | pmu->type = type; | |
10303 | ||
abe43400 PZ |
10304 | if (pmu_bus_running) { |
10305 | ret = pmu_dev_alloc(pmu); | |
10306 | if (ret) | |
10307 | goto free_idr; | |
10308 | } | |
10309 | ||
2e80a82a | 10310 | skip_type: |
26657848 PZ |
10311 | if (pmu->task_ctx_nr == perf_hw_context) { |
10312 | static int hw_context_taken = 0; | |
10313 | ||
5101ef20 MR |
10314 | /* |
10315 | * Other than systems with heterogeneous CPUs, it never makes | |
10316 | * sense for two PMUs to share perf_hw_context. PMUs which are | |
10317 | * uncore must use perf_invalid_context. | |
10318 | */ | |
10319 | if (WARN_ON_ONCE(hw_context_taken && | |
10320 | !(pmu->capabilities & PERF_PMU_CAP_HETEROGENEOUS_CPUS))) | |
26657848 PZ |
10321 | pmu->task_ctx_nr = perf_invalid_context; |
10322 | ||
10323 | hw_context_taken = 1; | |
10324 | } | |
10325 | ||
8dc85d54 PZ |
10326 | pmu->pmu_cpu_context = find_pmu_context(pmu->task_ctx_nr); |
10327 | if (pmu->pmu_cpu_context) | |
10328 | goto got_cpu_context; | |
f29ac756 | 10329 | |
c4814202 | 10330 | ret = -ENOMEM; |
108b02cf PZ |
10331 | pmu->pmu_cpu_context = alloc_percpu(struct perf_cpu_context); |
10332 | if (!pmu->pmu_cpu_context) | |
abe43400 | 10333 | goto free_dev; |
f344011c | 10334 | |
108b02cf PZ |
10335 | for_each_possible_cpu(cpu) { |
10336 | struct perf_cpu_context *cpuctx; | |
10337 | ||
10338 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
eb184479 | 10339 | __perf_event_init_context(&cpuctx->ctx); |
547e9fd7 | 10340 | lockdep_set_class(&cpuctx->ctx.mutex, &cpuctx_mutex); |
facc4307 | 10341 | lockdep_set_class(&cpuctx->ctx.lock, &cpuctx_lock); |
108b02cf | 10342 | cpuctx->ctx.pmu = pmu; |
a63fbed7 | 10343 | cpuctx->online = cpumask_test_cpu(cpu, perf_online_mask); |
9e630205 | 10344 | |
272325c4 | 10345 | __perf_mux_hrtimer_init(cpuctx, cpu); |
108b02cf | 10346 | } |
76e1d904 | 10347 | |
8dc85d54 | 10348 | got_cpu_context: |
ad5133b7 PZ |
10349 | if (!pmu->start_txn) { |
10350 | if (pmu->pmu_enable) { | |
10351 | /* | |
10352 | * If we have pmu_enable/pmu_disable calls, install | |
10353 | * transaction stubs that use that to try and batch | |
10354 | * hardware accesses. | |
10355 | */ | |
10356 | pmu->start_txn = perf_pmu_start_txn; | |
10357 | pmu->commit_txn = perf_pmu_commit_txn; | |
10358 | pmu->cancel_txn = perf_pmu_cancel_txn; | |
10359 | } else { | |
fbbe0701 | 10360 | pmu->start_txn = perf_pmu_nop_txn; |
ad5133b7 PZ |
10361 | pmu->commit_txn = perf_pmu_nop_int; |
10362 | pmu->cancel_txn = perf_pmu_nop_void; | |
f344011c | 10363 | } |
5c92d124 | 10364 | } |
15dbf27c | 10365 | |
ad5133b7 PZ |
10366 | if (!pmu->pmu_enable) { |
10367 | pmu->pmu_enable = perf_pmu_nop_void; | |
10368 | pmu->pmu_disable = perf_pmu_nop_void; | |
10369 | } | |
10370 | ||
81ec3f3c JO |
10371 | if (!pmu->check_period) |
10372 | pmu->check_period = perf_event_nop_int; | |
10373 | ||
35edc2a5 PZ |
10374 | if (!pmu->event_idx) |
10375 | pmu->event_idx = perf_event_idx_default; | |
10376 | ||
d44f821b LK |
10377 | /* |
10378 | * Ensure the TYPE_SOFTWARE PMUs are at the head of the list, | |
10379 | * since these cannot be in the IDR. This way the linear search | |
10380 | * is fast, provided a valid software event is provided. | |
10381 | */ | |
10382 | if (type == PERF_TYPE_SOFTWARE || !name) | |
10383 | list_add_rcu(&pmu->entry, &pmus); | |
10384 | else | |
10385 | list_add_tail_rcu(&pmu->entry, &pmus); | |
10386 | ||
bed5b25a | 10387 | atomic_set(&pmu->exclusive_cnt, 0); |
33696fc0 PZ |
10388 | ret = 0; |
10389 | unlock: | |
b0a873eb PZ |
10390 | mutex_unlock(&pmus_lock); |
10391 | ||
33696fc0 | 10392 | return ret; |
108b02cf | 10393 | |
abe43400 PZ |
10394 | free_dev: |
10395 | device_del(pmu->dev); | |
10396 | put_device(pmu->dev); | |
10397 | ||
2e80a82a | 10398 | free_idr: |
66d258c5 | 10399 | if (pmu->type != PERF_TYPE_SOFTWARE) |
2e80a82a PZ |
10400 | idr_remove(&pmu_idr, pmu->type); |
10401 | ||
108b02cf PZ |
10402 | free_pdc: |
10403 | free_percpu(pmu->pmu_disable_count); | |
10404 | goto unlock; | |
f29ac756 | 10405 | } |
c464c76e | 10406 | EXPORT_SYMBOL_GPL(perf_pmu_register); |
f29ac756 | 10407 | |
b0a873eb | 10408 | void perf_pmu_unregister(struct pmu *pmu) |
5c92d124 | 10409 | { |
b0a873eb PZ |
10410 | mutex_lock(&pmus_lock); |
10411 | list_del_rcu(&pmu->entry); | |
5c92d124 | 10412 | |
0475f9ea | 10413 | /* |
cde8e884 PZ |
10414 | * We dereference the pmu list under both SRCU and regular RCU, so |
10415 | * synchronize against both of those. | |
0475f9ea | 10416 | */ |
b0a873eb | 10417 | synchronize_srcu(&pmus_srcu); |
cde8e884 | 10418 | synchronize_rcu(); |
d6d020e9 | 10419 | |
33696fc0 | 10420 | free_percpu(pmu->pmu_disable_count); |
66d258c5 | 10421 | if (pmu->type != PERF_TYPE_SOFTWARE) |
2e80a82a | 10422 | idr_remove(&pmu_idr, pmu->type); |
a9f97721 | 10423 | if (pmu_bus_running) { |
0933840a JO |
10424 | if (pmu->nr_addr_filters) |
10425 | device_remove_file(pmu->dev, &dev_attr_nr_addr_filters); | |
10426 | device_del(pmu->dev); | |
10427 | put_device(pmu->dev); | |
10428 | } | |
51676957 | 10429 | free_pmu_context(pmu); |
a9f97721 | 10430 | mutex_unlock(&pmus_lock); |
b0a873eb | 10431 | } |
c464c76e | 10432 | EXPORT_SYMBOL_GPL(perf_pmu_unregister); |
d6d020e9 | 10433 | |
e321d02d KL |
10434 | static inline bool has_extended_regs(struct perf_event *event) |
10435 | { | |
10436 | return (event->attr.sample_regs_user & PERF_REG_EXTENDED_MASK) || | |
10437 | (event->attr.sample_regs_intr & PERF_REG_EXTENDED_MASK); | |
10438 | } | |
10439 | ||
cc34b98b MR |
10440 | static int perf_try_init_event(struct pmu *pmu, struct perf_event *event) |
10441 | { | |
ccd41c86 | 10442 | struct perf_event_context *ctx = NULL; |
cc34b98b MR |
10443 | int ret; |
10444 | ||
10445 | if (!try_module_get(pmu->module)) | |
10446 | return -ENODEV; | |
ccd41c86 | 10447 | |
0c7296ca PZ |
10448 | /* |
10449 | * A number of pmu->event_init() methods iterate the sibling_list to, | |
10450 | * for example, validate if the group fits on the PMU. Therefore, | |
10451 | * if this is a sibling event, acquire the ctx->mutex to protect | |
10452 | * the sibling_list. | |
10453 | */ | |
10454 | if (event->group_leader != event && pmu->task_ctx_nr != perf_sw_context) { | |
8b10c5e2 PZ |
10455 | /* |
10456 | * This ctx->mutex can nest when we're called through | |
10457 | * inheritance. See the perf_event_ctx_lock_nested() comment. | |
10458 | */ | |
10459 | ctx = perf_event_ctx_lock_nested(event->group_leader, | |
10460 | SINGLE_DEPTH_NESTING); | |
ccd41c86 PZ |
10461 | BUG_ON(!ctx); |
10462 | } | |
10463 | ||
cc34b98b MR |
10464 | event->pmu = pmu; |
10465 | ret = pmu->event_init(event); | |
ccd41c86 PZ |
10466 | |
10467 | if (ctx) | |
10468 | perf_event_ctx_unlock(event->group_leader, ctx); | |
10469 | ||
cc6795ae | 10470 | if (!ret) { |
e321d02d KL |
10471 | if (!(pmu->capabilities & PERF_PMU_CAP_EXTENDED_REGS) && |
10472 | has_extended_regs(event)) | |
10473 | ret = -EOPNOTSUPP; | |
10474 | ||
cc6795ae | 10475 | if (pmu->capabilities & PERF_PMU_CAP_NO_EXCLUDE && |
e321d02d | 10476 | event_has_any_exclude_flag(event)) |
cc6795ae | 10477 | ret = -EINVAL; |
e321d02d KL |
10478 | |
10479 | if (ret && event->destroy) | |
10480 | event->destroy(event); | |
cc6795ae AM |
10481 | } |
10482 | ||
cc34b98b MR |
10483 | if (ret) |
10484 | module_put(pmu->module); | |
10485 | ||
10486 | return ret; | |
10487 | } | |
10488 | ||
18ab2cd3 | 10489 | static struct pmu *perf_init_event(struct perf_event *event) |
b0a873eb | 10490 | { |
66d258c5 | 10491 | int idx, type, ret; |
85c617ab | 10492 | struct pmu *pmu; |
b0a873eb PZ |
10493 | |
10494 | idx = srcu_read_lock(&pmus_srcu); | |
2e80a82a | 10495 | |
40999312 KL |
10496 | /* Try parent's PMU first: */ |
10497 | if (event->parent && event->parent->pmu) { | |
10498 | pmu = event->parent->pmu; | |
10499 | ret = perf_try_init_event(pmu, event); | |
10500 | if (!ret) | |
10501 | goto unlock; | |
10502 | } | |
10503 | ||
66d258c5 PZ |
10504 | /* |
10505 | * PERF_TYPE_HARDWARE and PERF_TYPE_HW_CACHE | |
10506 | * are often aliases for PERF_TYPE_RAW. | |
10507 | */ | |
10508 | type = event->attr.type; | |
10509 | if (type == PERF_TYPE_HARDWARE || type == PERF_TYPE_HW_CACHE) | |
10510 | type = PERF_TYPE_RAW; | |
10511 | ||
10512 | again: | |
2e80a82a | 10513 | rcu_read_lock(); |
66d258c5 | 10514 | pmu = idr_find(&pmu_idr, type); |
2e80a82a | 10515 | rcu_read_unlock(); |
940c5b29 | 10516 | if (pmu) { |
cc34b98b | 10517 | ret = perf_try_init_event(pmu, event); |
66d258c5 PZ |
10518 | if (ret == -ENOENT && event->attr.type != type) { |
10519 | type = event->attr.type; | |
10520 | goto again; | |
10521 | } | |
10522 | ||
940c5b29 LM |
10523 | if (ret) |
10524 | pmu = ERR_PTR(ret); | |
66d258c5 | 10525 | |
2e80a82a | 10526 | goto unlock; |
940c5b29 | 10527 | } |
2e80a82a | 10528 | |
9f0bff11 | 10529 | list_for_each_entry_rcu(pmu, &pmus, entry, lockdep_is_held(&pmus_srcu)) { |
cc34b98b | 10530 | ret = perf_try_init_event(pmu, event); |
b0a873eb | 10531 | if (!ret) |
e5f4d339 | 10532 | goto unlock; |
76e1d904 | 10533 | |
b0a873eb PZ |
10534 | if (ret != -ENOENT) { |
10535 | pmu = ERR_PTR(ret); | |
e5f4d339 | 10536 | goto unlock; |
f344011c | 10537 | } |
5c92d124 | 10538 | } |
e5f4d339 PZ |
10539 | pmu = ERR_PTR(-ENOENT); |
10540 | unlock: | |
b0a873eb | 10541 | srcu_read_unlock(&pmus_srcu, idx); |
15dbf27c | 10542 | |
4aeb0b42 | 10543 | return pmu; |
5c92d124 IM |
10544 | } |
10545 | ||
f2fb6bef KL |
10546 | static void attach_sb_event(struct perf_event *event) |
10547 | { | |
10548 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
10549 | ||
10550 | raw_spin_lock(&pel->lock); | |
10551 | list_add_rcu(&event->sb_list, &pel->list); | |
10552 | raw_spin_unlock(&pel->lock); | |
10553 | } | |
10554 | ||
aab5b71e PZ |
10555 | /* |
10556 | * We keep a list of all !task (and therefore per-cpu) events | |
10557 | * that need to receive side-band records. | |
10558 | * | |
10559 | * This avoids having to scan all the various PMU per-cpu contexts | |
10560 | * looking for them. | |
10561 | */ | |
f2fb6bef KL |
10562 | static void account_pmu_sb_event(struct perf_event *event) |
10563 | { | |
a4f144eb | 10564 | if (is_sb_event(event)) |
f2fb6bef KL |
10565 | attach_sb_event(event); |
10566 | } | |
10567 | ||
4beb31f3 FW |
10568 | static void account_event_cpu(struct perf_event *event, int cpu) |
10569 | { | |
10570 | if (event->parent) | |
10571 | return; | |
10572 | ||
4beb31f3 FW |
10573 | if (is_cgroup_event(event)) |
10574 | atomic_inc(&per_cpu(perf_cgroup_events, cpu)); | |
10575 | } | |
10576 | ||
555e0c1e FW |
10577 | /* Freq events need the tick to stay alive (see perf_event_task_tick). */ |
10578 | static void account_freq_event_nohz(void) | |
10579 | { | |
10580 | #ifdef CONFIG_NO_HZ_FULL | |
10581 | /* Lock so we don't race with concurrent unaccount */ | |
10582 | spin_lock(&nr_freq_lock); | |
10583 | if (atomic_inc_return(&nr_freq_events) == 1) | |
10584 | tick_nohz_dep_set(TICK_DEP_BIT_PERF_EVENTS); | |
10585 | spin_unlock(&nr_freq_lock); | |
10586 | #endif | |
10587 | } | |
10588 | ||
10589 | static void account_freq_event(void) | |
10590 | { | |
10591 | if (tick_nohz_full_enabled()) | |
10592 | account_freq_event_nohz(); | |
10593 | else | |
10594 | atomic_inc(&nr_freq_events); | |
10595 | } | |
10596 | ||
10597 | ||
766d6c07 FW |
10598 | static void account_event(struct perf_event *event) |
10599 | { | |
25432ae9 PZ |
10600 | bool inc = false; |
10601 | ||
4beb31f3 FW |
10602 | if (event->parent) |
10603 | return; | |
10604 | ||
766d6c07 | 10605 | if (event->attach_state & PERF_ATTACH_TASK) |
25432ae9 | 10606 | inc = true; |
766d6c07 FW |
10607 | if (event->attr.mmap || event->attr.mmap_data) |
10608 | atomic_inc(&nr_mmap_events); | |
10609 | if (event->attr.comm) | |
10610 | atomic_inc(&nr_comm_events); | |
e4222673 HB |
10611 | if (event->attr.namespaces) |
10612 | atomic_inc(&nr_namespaces_events); | |
766d6c07 FW |
10613 | if (event->attr.task) |
10614 | atomic_inc(&nr_task_events); | |
555e0c1e FW |
10615 | if (event->attr.freq) |
10616 | account_freq_event(); | |
45ac1403 AH |
10617 | if (event->attr.context_switch) { |
10618 | atomic_inc(&nr_switch_events); | |
25432ae9 | 10619 | inc = true; |
45ac1403 | 10620 | } |
4beb31f3 | 10621 | if (has_branch_stack(event)) |
25432ae9 | 10622 | inc = true; |
4beb31f3 | 10623 | if (is_cgroup_event(event)) |
25432ae9 | 10624 | inc = true; |
76193a94 SL |
10625 | if (event->attr.ksymbol) |
10626 | atomic_inc(&nr_ksymbol_events); | |
6ee52e2a SL |
10627 | if (event->attr.bpf_event) |
10628 | atomic_inc(&nr_bpf_events); | |
25432ae9 | 10629 | |
9107c89e | 10630 | if (inc) { |
5bce9db1 AS |
10631 | /* |
10632 | * We need the mutex here because static_branch_enable() | |
10633 | * must complete *before* the perf_sched_count increment | |
10634 | * becomes visible. | |
10635 | */ | |
9107c89e PZ |
10636 | if (atomic_inc_not_zero(&perf_sched_count)) |
10637 | goto enabled; | |
10638 | ||
10639 | mutex_lock(&perf_sched_mutex); | |
10640 | if (!atomic_read(&perf_sched_count)) { | |
10641 | static_branch_enable(&perf_sched_events); | |
10642 | /* | |
10643 | * Guarantee that all CPUs observe they key change and | |
10644 | * call the perf scheduling hooks before proceeding to | |
10645 | * install events that need them. | |
10646 | */ | |
0809d954 | 10647 | synchronize_rcu(); |
9107c89e PZ |
10648 | } |
10649 | /* | |
10650 | * Now that we have waited for the sync_sched(), allow further | |
10651 | * increments to by-pass the mutex. | |
10652 | */ | |
10653 | atomic_inc(&perf_sched_count); | |
10654 | mutex_unlock(&perf_sched_mutex); | |
10655 | } | |
10656 | enabled: | |
4beb31f3 FW |
10657 | |
10658 | account_event_cpu(event, event->cpu); | |
f2fb6bef KL |
10659 | |
10660 | account_pmu_sb_event(event); | |
766d6c07 FW |
10661 | } |
10662 | ||
0793a61d | 10663 | /* |
788faab7 | 10664 | * Allocate and initialize an event structure |
0793a61d | 10665 | */ |
cdd6c482 | 10666 | static struct perf_event * |
c3f00c70 | 10667 | perf_event_alloc(struct perf_event_attr *attr, int cpu, |
d580ff86 PZ |
10668 | struct task_struct *task, |
10669 | struct perf_event *group_leader, | |
10670 | struct perf_event *parent_event, | |
4dc0da86 | 10671 | perf_overflow_handler_t overflow_handler, |
79dff51e | 10672 | void *context, int cgroup_fd) |
0793a61d | 10673 | { |
51b0fe39 | 10674 | struct pmu *pmu; |
cdd6c482 IM |
10675 | struct perf_event *event; |
10676 | struct hw_perf_event *hwc; | |
90983b16 | 10677 | long err = -EINVAL; |
0793a61d | 10678 | |
66832eb4 ON |
10679 | if ((unsigned)cpu >= nr_cpu_ids) { |
10680 | if (!task || cpu != -1) | |
10681 | return ERR_PTR(-EINVAL); | |
10682 | } | |
10683 | ||
c3f00c70 | 10684 | event = kzalloc(sizeof(*event), GFP_KERNEL); |
cdd6c482 | 10685 | if (!event) |
d5d2bc0d | 10686 | return ERR_PTR(-ENOMEM); |
0793a61d | 10687 | |
04289bb9 | 10688 | /* |
cdd6c482 | 10689 | * Single events are their own group leaders, with an |
04289bb9 IM |
10690 | * empty sibling list: |
10691 | */ | |
10692 | if (!group_leader) | |
cdd6c482 | 10693 | group_leader = event; |
04289bb9 | 10694 | |
cdd6c482 IM |
10695 | mutex_init(&event->child_mutex); |
10696 | INIT_LIST_HEAD(&event->child_list); | |
fccc714b | 10697 | |
cdd6c482 IM |
10698 | INIT_LIST_HEAD(&event->event_entry); |
10699 | INIT_LIST_HEAD(&event->sibling_list); | |
6668128a | 10700 | INIT_LIST_HEAD(&event->active_list); |
8e1a2031 | 10701 | init_event_group(event); |
10c6db11 | 10702 | INIT_LIST_HEAD(&event->rb_entry); |
71ad88ef | 10703 | INIT_LIST_HEAD(&event->active_entry); |
375637bc | 10704 | INIT_LIST_HEAD(&event->addr_filters.list); |
f3ae75de SE |
10705 | INIT_HLIST_NODE(&event->hlist_entry); |
10706 | ||
10c6db11 | 10707 | |
cdd6c482 | 10708 | init_waitqueue_head(&event->waitq); |
1d54ad94 | 10709 | event->pending_disable = -1; |
e360adbe | 10710 | init_irq_work(&event->pending, perf_pending_event); |
0793a61d | 10711 | |
cdd6c482 | 10712 | mutex_init(&event->mmap_mutex); |
375637bc | 10713 | raw_spin_lock_init(&event->addr_filters.lock); |
7b732a75 | 10714 | |
a6fa941d | 10715 | atomic_long_set(&event->refcount, 1); |
cdd6c482 IM |
10716 | event->cpu = cpu; |
10717 | event->attr = *attr; | |
10718 | event->group_leader = group_leader; | |
10719 | event->pmu = NULL; | |
cdd6c482 | 10720 | event->oncpu = -1; |
a96bbc16 | 10721 | |
cdd6c482 | 10722 | event->parent = parent_event; |
b84fbc9f | 10723 | |
17cf22c3 | 10724 | event->ns = get_pid_ns(task_active_pid_ns(current)); |
cdd6c482 | 10725 | event->id = atomic64_inc_return(&perf_event_id); |
a96bbc16 | 10726 | |
cdd6c482 | 10727 | event->state = PERF_EVENT_STATE_INACTIVE; |
329d876d | 10728 | |
d580ff86 PZ |
10729 | if (task) { |
10730 | event->attach_state = PERF_ATTACH_TASK; | |
d580ff86 | 10731 | /* |
50f16a8b PZ |
10732 | * XXX pmu::event_init needs to know what task to account to |
10733 | * and we cannot use the ctx information because we need the | |
10734 | * pmu before we get a ctx. | |
d580ff86 | 10735 | */ |
7b3c92b8 | 10736 | event->hw.target = get_task_struct(task); |
d580ff86 PZ |
10737 | } |
10738 | ||
34f43927 PZ |
10739 | event->clock = &local_clock; |
10740 | if (parent_event) | |
10741 | event->clock = parent_event->clock; | |
10742 | ||
4dc0da86 | 10743 | if (!overflow_handler && parent_event) { |
b326e956 | 10744 | overflow_handler = parent_event->overflow_handler; |
4dc0da86 | 10745 | context = parent_event->overflow_handler_context; |
f1e4ba5b | 10746 | #if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_EVENT_TRACING) |
aa6a5f3c | 10747 | if (overflow_handler == bpf_overflow_handler) { |
85192dbf | 10748 | struct bpf_prog *prog = parent_event->prog; |
aa6a5f3c | 10749 | |
85192dbf | 10750 | bpf_prog_inc(prog); |
aa6a5f3c AS |
10751 | event->prog = prog; |
10752 | event->orig_overflow_handler = | |
10753 | parent_event->orig_overflow_handler; | |
10754 | } | |
10755 | #endif | |
4dc0da86 | 10756 | } |
66832eb4 | 10757 | |
1879445d WN |
10758 | if (overflow_handler) { |
10759 | event->overflow_handler = overflow_handler; | |
10760 | event->overflow_handler_context = context; | |
9ecda41a WN |
10761 | } else if (is_write_backward(event)){ |
10762 | event->overflow_handler = perf_event_output_backward; | |
10763 | event->overflow_handler_context = NULL; | |
1879445d | 10764 | } else { |
9ecda41a | 10765 | event->overflow_handler = perf_event_output_forward; |
1879445d WN |
10766 | event->overflow_handler_context = NULL; |
10767 | } | |
97eaf530 | 10768 | |
0231bb53 | 10769 | perf_event__state_init(event); |
a86ed508 | 10770 | |
4aeb0b42 | 10771 | pmu = NULL; |
b8e83514 | 10772 | |
cdd6c482 | 10773 | hwc = &event->hw; |
bd2b5b12 | 10774 | hwc->sample_period = attr->sample_period; |
0d48696f | 10775 | if (attr->freq && attr->sample_freq) |
bd2b5b12 | 10776 | hwc->sample_period = 1; |
eced1dfc | 10777 | hwc->last_period = hwc->sample_period; |
bd2b5b12 | 10778 | |
e7850595 | 10779 | local64_set(&hwc->period_left, hwc->sample_period); |
60db5e09 | 10780 | |
2023b359 | 10781 | /* |
ba5213ae PZ |
10782 | * We currently do not support PERF_SAMPLE_READ on inherited events. |
10783 | * See perf_output_read(). | |
2023b359 | 10784 | */ |
ba5213ae | 10785 | if (attr->inherit && (attr->sample_type & PERF_SAMPLE_READ)) |
90983b16 | 10786 | goto err_ns; |
a46a2300 YZ |
10787 | |
10788 | if (!has_branch_stack(event)) | |
10789 | event->attr.branch_sample_type = 0; | |
2023b359 | 10790 | |
79dff51e MF |
10791 | if (cgroup_fd != -1) { |
10792 | err = perf_cgroup_connect(cgroup_fd, event, attr, group_leader); | |
10793 | if (err) | |
10794 | goto err_ns; | |
10795 | } | |
10796 | ||
b0a873eb | 10797 | pmu = perf_init_event(event); |
85c617ab | 10798 | if (IS_ERR(pmu)) { |
4aeb0b42 | 10799 | err = PTR_ERR(pmu); |
90983b16 | 10800 | goto err_ns; |
621a01ea | 10801 | } |
d5d2bc0d | 10802 | |
09f4e8f0 PZ |
10803 | /* |
10804 | * Disallow uncore-cgroup events, they don't make sense as the cgroup will | |
10805 | * be different on other CPUs in the uncore mask. | |
10806 | */ | |
10807 | if (pmu->task_ctx_nr == perf_invalid_context && cgroup_fd != -1) { | |
10808 | err = -EINVAL; | |
10809 | goto err_pmu; | |
10810 | } | |
10811 | ||
ab43762e AS |
10812 | if (event->attr.aux_output && |
10813 | !(pmu->capabilities & PERF_PMU_CAP_AUX_OUTPUT)) { | |
10814 | err = -EOPNOTSUPP; | |
10815 | goto err_pmu; | |
10816 | } | |
10817 | ||
bed5b25a AS |
10818 | err = exclusive_event_init(event); |
10819 | if (err) | |
10820 | goto err_pmu; | |
10821 | ||
375637bc | 10822 | if (has_addr_filter(event)) { |
c60f83b8 AS |
10823 | event->addr_filter_ranges = kcalloc(pmu->nr_addr_filters, |
10824 | sizeof(struct perf_addr_filter_range), | |
10825 | GFP_KERNEL); | |
10826 | if (!event->addr_filter_ranges) { | |
36cc2b92 | 10827 | err = -ENOMEM; |
375637bc | 10828 | goto err_per_task; |
36cc2b92 | 10829 | } |
375637bc | 10830 | |
18736eef AS |
10831 | /* |
10832 | * Clone the parent's vma offsets: they are valid until exec() | |
10833 | * even if the mm is not shared with the parent. | |
10834 | */ | |
10835 | if (event->parent) { | |
10836 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
10837 | ||
10838 | raw_spin_lock_irq(&ifh->lock); | |
c60f83b8 AS |
10839 | memcpy(event->addr_filter_ranges, |
10840 | event->parent->addr_filter_ranges, | |
10841 | pmu->nr_addr_filters * sizeof(struct perf_addr_filter_range)); | |
18736eef AS |
10842 | raw_spin_unlock_irq(&ifh->lock); |
10843 | } | |
10844 | ||
375637bc AS |
10845 | /* force hw sync on the address filters */ |
10846 | event->addr_filters_gen = 1; | |
10847 | } | |
10848 | ||
cdd6c482 | 10849 | if (!event->parent) { |
927c7a9e | 10850 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) { |
97c79a38 | 10851 | err = get_callchain_buffers(attr->sample_max_stack); |
90983b16 | 10852 | if (err) |
375637bc | 10853 | goto err_addr_filters; |
d010b332 | 10854 | } |
f344011c | 10855 | } |
9ee318a7 | 10856 | |
da97e184 JFG |
10857 | err = security_perf_event_alloc(event); |
10858 | if (err) | |
10859 | goto err_callchain_buffer; | |
10860 | ||
927a5570 AS |
10861 | /* symmetric to unaccount_event() in _free_event() */ |
10862 | account_event(event); | |
10863 | ||
cdd6c482 | 10864 | return event; |
90983b16 | 10865 | |
da97e184 JFG |
10866 | err_callchain_buffer: |
10867 | if (!event->parent) { | |
10868 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) | |
10869 | put_callchain_buffers(); | |
10870 | } | |
375637bc | 10871 | err_addr_filters: |
c60f83b8 | 10872 | kfree(event->addr_filter_ranges); |
375637bc | 10873 | |
bed5b25a AS |
10874 | err_per_task: |
10875 | exclusive_event_destroy(event); | |
10876 | ||
90983b16 FW |
10877 | err_pmu: |
10878 | if (event->destroy) | |
10879 | event->destroy(event); | |
c464c76e | 10880 | module_put(pmu->module); |
90983b16 | 10881 | err_ns: |
79dff51e MF |
10882 | if (is_cgroup_event(event)) |
10883 | perf_detach_cgroup(event); | |
90983b16 FW |
10884 | if (event->ns) |
10885 | put_pid_ns(event->ns); | |
621b6d2e PB |
10886 | if (event->hw.target) |
10887 | put_task_struct(event->hw.target); | |
90983b16 FW |
10888 | kfree(event); |
10889 | ||
10890 | return ERR_PTR(err); | |
0793a61d TG |
10891 | } |
10892 | ||
cdd6c482 IM |
10893 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
10894 | struct perf_event_attr *attr) | |
974802ea | 10895 | { |
974802ea | 10896 | u32 size; |
cdf8073d | 10897 | int ret; |
974802ea | 10898 | |
c2ba8f41 | 10899 | /* Zero the full structure, so that a short copy will be nice. */ |
974802ea PZ |
10900 | memset(attr, 0, sizeof(*attr)); |
10901 | ||
10902 | ret = get_user(size, &uattr->size); | |
10903 | if (ret) | |
10904 | return ret; | |
10905 | ||
c2ba8f41 AS |
10906 | /* ABI compatibility quirk: */ |
10907 | if (!size) | |
974802ea | 10908 | size = PERF_ATTR_SIZE_VER0; |
c2ba8f41 | 10909 | if (size < PERF_ATTR_SIZE_VER0 || size > PAGE_SIZE) |
974802ea PZ |
10910 | goto err_size; |
10911 | ||
c2ba8f41 AS |
10912 | ret = copy_struct_from_user(attr, sizeof(*attr), uattr, size); |
10913 | if (ret) { | |
10914 | if (ret == -E2BIG) | |
10915 | goto err_size; | |
10916 | return ret; | |
974802ea PZ |
10917 | } |
10918 | ||
f12f42ac MX |
10919 | attr->size = size; |
10920 | ||
a4faf00d | 10921 | if (attr->__reserved_1 || attr->__reserved_2 || attr->__reserved_3) |
974802ea PZ |
10922 | return -EINVAL; |
10923 | ||
10924 | if (attr->sample_type & ~(PERF_SAMPLE_MAX-1)) | |
10925 | return -EINVAL; | |
10926 | ||
10927 | if (attr->read_format & ~(PERF_FORMAT_MAX-1)) | |
10928 | return -EINVAL; | |
10929 | ||
bce38cd5 SE |
10930 | if (attr->sample_type & PERF_SAMPLE_BRANCH_STACK) { |
10931 | u64 mask = attr->branch_sample_type; | |
10932 | ||
10933 | /* only using defined bits */ | |
10934 | if (mask & ~(PERF_SAMPLE_BRANCH_MAX-1)) | |
10935 | return -EINVAL; | |
10936 | ||
10937 | /* at least one branch bit must be set */ | |
10938 | if (!(mask & ~PERF_SAMPLE_BRANCH_PLM_ALL)) | |
10939 | return -EINVAL; | |
10940 | ||
bce38cd5 SE |
10941 | /* propagate priv level, when not set for branch */ |
10942 | if (!(mask & PERF_SAMPLE_BRANCH_PLM_ALL)) { | |
10943 | ||
10944 | /* exclude_kernel checked on syscall entry */ | |
10945 | if (!attr->exclude_kernel) | |
10946 | mask |= PERF_SAMPLE_BRANCH_KERNEL; | |
10947 | ||
10948 | if (!attr->exclude_user) | |
10949 | mask |= PERF_SAMPLE_BRANCH_USER; | |
10950 | ||
10951 | if (!attr->exclude_hv) | |
10952 | mask |= PERF_SAMPLE_BRANCH_HV; | |
10953 | /* | |
10954 | * adjust user setting (for HW filter setup) | |
10955 | */ | |
10956 | attr->branch_sample_type = mask; | |
10957 | } | |
e712209a | 10958 | /* privileged levels capture (kernel, hv): check permissions */ |
da97e184 JFG |
10959 | if (mask & PERF_SAMPLE_BRANCH_PERM_PLM) { |
10960 | ret = perf_allow_kernel(attr); | |
10961 | if (ret) | |
10962 | return ret; | |
10963 | } | |
bce38cd5 | 10964 | } |
4018994f | 10965 | |
c5ebcedb | 10966 | if (attr->sample_type & PERF_SAMPLE_REGS_USER) { |
4018994f | 10967 | ret = perf_reg_validate(attr->sample_regs_user); |
c5ebcedb JO |
10968 | if (ret) |
10969 | return ret; | |
10970 | } | |
10971 | ||
10972 | if (attr->sample_type & PERF_SAMPLE_STACK_USER) { | |
10973 | if (!arch_perf_have_user_stack_dump()) | |
10974 | return -ENOSYS; | |
10975 | ||
10976 | /* | |
10977 | * We have __u32 type for the size, but so far | |
10978 | * we can only use __u16 as maximum due to the | |
10979 | * __u16 sample size limit. | |
10980 | */ | |
10981 | if (attr->sample_stack_user >= USHRT_MAX) | |
78b562fb | 10982 | return -EINVAL; |
c5ebcedb | 10983 | else if (!IS_ALIGNED(attr->sample_stack_user, sizeof(u64))) |
78b562fb | 10984 | return -EINVAL; |
c5ebcedb | 10985 | } |
4018994f | 10986 | |
5f970521 JO |
10987 | if (!attr->sample_max_stack) |
10988 | attr->sample_max_stack = sysctl_perf_event_max_stack; | |
10989 | ||
60e2364e SE |
10990 | if (attr->sample_type & PERF_SAMPLE_REGS_INTR) |
10991 | ret = perf_reg_validate(attr->sample_regs_intr); | |
974802ea PZ |
10992 | out: |
10993 | return ret; | |
10994 | ||
10995 | err_size: | |
10996 | put_user(sizeof(*attr), &uattr->size); | |
10997 | ret = -E2BIG; | |
10998 | goto out; | |
10999 | } | |
11000 | ||
ac9721f3 PZ |
11001 | static int |
11002 | perf_event_set_output(struct perf_event *event, struct perf_event *output_event) | |
a4be7c27 | 11003 | { |
56de4e8f | 11004 | struct perf_buffer *rb = NULL; |
a4be7c27 PZ |
11005 | int ret = -EINVAL; |
11006 | ||
ac9721f3 | 11007 | if (!output_event) |
a4be7c27 PZ |
11008 | goto set; |
11009 | ||
ac9721f3 PZ |
11010 | /* don't allow circular references */ |
11011 | if (event == output_event) | |
a4be7c27 PZ |
11012 | goto out; |
11013 | ||
0f139300 PZ |
11014 | /* |
11015 | * Don't allow cross-cpu buffers | |
11016 | */ | |
11017 | if (output_event->cpu != event->cpu) | |
11018 | goto out; | |
11019 | ||
11020 | /* | |
76369139 | 11021 | * If its not a per-cpu rb, it must be the same task. |
0f139300 PZ |
11022 | */ |
11023 | if (output_event->cpu == -1 && output_event->ctx != event->ctx) | |
11024 | goto out; | |
11025 | ||
34f43927 PZ |
11026 | /* |
11027 | * Mixing clocks in the same buffer is trouble you don't need. | |
11028 | */ | |
11029 | if (output_event->clock != event->clock) | |
11030 | goto out; | |
11031 | ||
9ecda41a WN |
11032 | /* |
11033 | * Either writing ring buffer from beginning or from end. | |
11034 | * Mixing is not allowed. | |
11035 | */ | |
11036 | if (is_write_backward(output_event) != is_write_backward(event)) | |
11037 | goto out; | |
11038 | ||
45bfb2e5 PZ |
11039 | /* |
11040 | * If both events generate aux data, they must be on the same PMU | |
11041 | */ | |
11042 | if (has_aux(event) && has_aux(output_event) && | |
11043 | event->pmu != output_event->pmu) | |
11044 | goto out; | |
11045 | ||
a4be7c27 | 11046 | set: |
cdd6c482 | 11047 | mutex_lock(&event->mmap_mutex); |
ac9721f3 PZ |
11048 | /* Can't redirect output if we've got an active mmap() */ |
11049 | if (atomic_read(&event->mmap_count)) | |
11050 | goto unlock; | |
a4be7c27 | 11051 | |
ac9721f3 | 11052 | if (output_event) { |
76369139 FW |
11053 | /* get the rb we want to redirect to */ |
11054 | rb = ring_buffer_get(output_event); | |
11055 | if (!rb) | |
ac9721f3 | 11056 | goto unlock; |
a4be7c27 PZ |
11057 | } |
11058 | ||
b69cf536 | 11059 | ring_buffer_attach(event, rb); |
9bb5d40c | 11060 | |
a4be7c27 | 11061 | ret = 0; |
ac9721f3 PZ |
11062 | unlock: |
11063 | mutex_unlock(&event->mmap_mutex); | |
11064 | ||
a4be7c27 | 11065 | out: |
a4be7c27 PZ |
11066 | return ret; |
11067 | } | |
11068 | ||
f63a8daa PZ |
11069 | static void mutex_lock_double(struct mutex *a, struct mutex *b) |
11070 | { | |
11071 | if (b < a) | |
11072 | swap(a, b); | |
11073 | ||
11074 | mutex_lock(a); | |
11075 | mutex_lock_nested(b, SINGLE_DEPTH_NESTING); | |
11076 | } | |
11077 | ||
34f43927 PZ |
11078 | static int perf_event_set_clock(struct perf_event *event, clockid_t clk_id) |
11079 | { | |
11080 | bool nmi_safe = false; | |
11081 | ||
11082 | switch (clk_id) { | |
11083 | case CLOCK_MONOTONIC: | |
11084 | event->clock = &ktime_get_mono_fast_ns; | |
11085 | nmi_safe = true; | |
11086 | break; | |
11087 | ||
11088 | case CLOCK_MONOTONIC_RAW: | |
11089 | event->clock = &ktime_get_raw_fast_ns; | |
11090 | nmi_safe = true; | |
11091 | break; | |
11092 | ||
11093 | case CLOCK_REALTIME: | |
11094 | event->clock = &ktime_get_real_ns; | |
11095 | break; | |
11096 | ||
11097 | case CLOCK_BOOTTIME: | |
9285ec4c | 11098 | event->clock = &ktime_get_boottime_ns; |
34f43927 PZ |
11099 | break; |
11100 | ||
11101 | case CLOCK_TAI: | |
9285ec4c | 11102 | event->clock = &ktime_get_clocktai_ns; |
34f43927 PZ |
11103 | break; |
11104 | ||
11105 | default: | |
11106 | return -EINVAL; | |
11107 | } | |
11108 | ||
11109 | if (!nmi_safe && !(event->pmu->capabilities & PERF_PMU_CAP_NO_NMI)) | |
11110 | return -EINVAL; | |
11111 | ||
11112 | return 0; | |
11113 | } | |
11114 | ||
321027c1 PZ |
11115 | /* |
11116 | * Variation on perf_event_ctx_lock_nested(), except we take two context | |
11117 | * mutexes. | |
11118 | */ | |
11119 | static struct perf_event_context * | |
11120 | __perf_event_ctx_lock_double(struct perf_event *group_leader, | |
11121 | struct perf_event_context *ctx) | |
11122 | { | |
11123 | struct perf_event_context *gctx; | |
11124 | ||
11125 | again: | |
11126 | rcu_read_lock(); | |
11127 | gctx = READ_ONCE(group_leader->ctx); | |
8c94abbb | 11128 | if (!refcount_inc_not_zero(&gctx->refcount)) { |
321027c1 PZ |
11129 | rcu_read_unlock(); |
11130 | goto again; | |
11131 | } | |
11132 | rcu_read_unlock(); | |
11133 | ||
11134 | mutex_lock_double(&gctx->mutex, &ctx->mutex); | |
11135 | ||
11136 | if (group_leader->ctx != gctx) { | |
11137 | mutex_unlock(&ctx->mutex); | |
11138 | mutex_unlock(&gctx->mutex); | |
11139 | put_ctx(gctx); | |
11140 | goto again; | |
11141 | } | |
11142 | ||
11143 | return gctx; | |
11144 | } | |
11145 | ||
0793a61d | 11146 | /** |
cdd6c482 | 11147 | * sys_perf_event_open - open a performance event, associate it to a task/cpu |
9f66a381 | 11148 | * |
cdd6c482 | 11149 | * @attr_uptr: event_id type attributes for monitoring/sampling |
0793a61d | 11150 | * @pid: target pid |
9f66a381 | 11151 | * @cpu: target cpu |
cdd6c482 | 11152 | * @group_fd: group leader event fd |
0793a61d | 11153 | */ |
cdd6c482 IM |
11154 | SYSCALL_DEFINE5(perf_event_open, |
11155 | struct perf_event_attr __user *, attr_uptr, | |
2743a5b0 | 11156 | pid_t, pid, int, cpu, int, group_fd, unsigned long, flags) |
0793a61d | 11157 | { |
b04243ef PZ |
11158 | struct perf_event *group_leader = NULL, *output_event = NULL; |
11159 | struct perf_event *event, *sibling; | |
cdd6c482 | 11160 | struct perf_event_attr attr; |
f63a8daa | 11161 | struct perf_event_context *ctx, *uninitialized_var(gctx); |
cdd6c482 | 11162 | struct file *event_file = NULL; |
2903ff01 | 11163 | struct fd group = {NULL, 0}; |
38a81da2 | 11164 | struct task_struct *task = NULL; |
89a1e187 | 11165 | struct pmu *pmu; |
ea635c64 | 11166 | int event_fd; |
b04243ef | 11167 | int move_group = 0; |
dc86cabe | 11168 | int err; |
a21b0b35 | 11169 | int f_flags = O_RDWR; |
79dff51e | 11170 | int cgroup_fd = -1; |
0793a61d | 11171 | |
2743a5b0 | 11172 | /* for future expandability... */ |
e5d1367f | 11173 | if (flags & ~PERF_FLAG_ALL) |
2743a5b0 PM |
11174 | return -EINVAL; |
11175 | ||
da97e184 JFG |
11176 | /* Do we allow access to perf_event_open(2) ? */ |
11177 | err = security_perf_event_open(&attr, PERF_SECURITY_OPEN); | |
11178 | if (err) | |
11179 | return err; | |
11180 | ||
dc86cabe IM |
11181 | err = perf_copy_attr(attr_uptr, &attr); |
11182 | if (err) | |
11183 | return err; | |
eab656ae | 11184 | |
0764771d | 11185 | if (!attr.exclude_kernel) { |
da97e184 JFG |
11186 | err = perf_allow_kernel(&attr); |
11187 | if (err) | |
11188 | return err; | |
0764771d PZ |
11189 | } |
11190 | ||
e4222673 HB |
11191 | if (attr.namespaces) { |
11192 | if (!capable(CAP_SYS_ADMIN)) | |
11193 | return -EACCES; | |
11194 | } | |
11195 | ||
df58ab24 | 11196 | if (attr.freq) { |
cdd6c482 | 11197 | if (attr.sample_freq > sysctl_perf_event_sample_rate) |
df58ab24 | 11198 | return -EINVAL; |
0819b2e3 PZ |
11199 | } else { |
11200 | if (attr.sample_period & (1ULL << 63)) | |
11201 | return -EINVAL; | |
df58ab24 PZ |
11202 | } |
11203 | ||
fc7ce9c7 | 11204 | /* Only privileged users can get physical addresses */ |
da97e184 JFG |
11205 | if ((attr.sample_type & PERF_SAMPLE_PHYS_ADDR)) { |
11206 | err = perf_allow_kernel(&attr); | |
11207 | if (err) | |
11208 | return err; | |
11209 | } | |
fc7ce9c7 | 11210 | |
b0c8fdc7 DH |
11211 | err = security_locked_down(LOCKDOWN_PERF); |
11212 | if (err && (attr.sample_type & PERF_SAMPLE_REGS_INTR)) | |
11213 | /* REGS_INTR can leak data, lockdown must prevent this */ | |
11214 | return err; | |
11215 | ||
11216 | err = 0; | |
11217 | ||
e5d1367f SE |
11218 | /* |
11219 | * In cgroup mode, the pid argument is used to pass the fd | |
11220 | * opened to the cgroup directory in cgroupfs. The cpu argument | |
11221 | * designates the cpu on which to monitor threads from that | |
11222 | * cgroup. | |
11223 | */ | |
11224 | if ((flags & PERF_FLAG_PID_CGROUP) && (pid == -1 || cpu == -1)) | |
11225 | return -EINVAL; | |
11226 | ||
a21b0b35 YD |
11227 | if (flags & PERF_FLAG_FD_CLOEXEC) |
11228 | f_flags |= O_CLOEXEC; | |
11229 | ||
11230 | event_fd = get_unused_fd_flags(f_flags); | |
ea635c64 AV |
11231 | if (event_fd < 0) |
11232 | return event_fd; | |
11233 | ||
ac9721f3 | 11234 | if (group_fd != -1) { |
2903ff01 AV |
11235 | err = perf_fget_light(group_fd, &group); |
11236 | if (err) | |
d14b12d7 | 11237 | goto err_fd; |
2903ff01 | 11238 | group_leader = group.file->private_data; |
ac9721f3 PZ |
11239 | if (flags & PERF_FLAG_FD_OUTPUT) |
11240 | output_event = group_leader; | |
11241 | if (flags & PERF_FLAG_FD_NO_GROUP) | |
11242 | group_leader = NULL; | |
11243 | } | |
11244 | ||
e5d1367f | 11245 | if (pid != -1 && !(flags & PERF_FLAG_PID_CGROUP)) { |
c6be5a5c PZ |
11246 | task = find_lively_task_by_vpid(pid); |
11247 | if (IS_ERR(task)) { | |
11248 | err = PTR_ERR(task); | |
11249 | goto err_group_fd; | |
11250 | } | |
11251 | } | |
11252 | ||
1f4ee503 PZ |
11253 | if (task && group_leader && |
11254 | group_leader->attr.inherit != attr.inherit) { | |
11255 | err = -EINVAL; | |
11256 | goto err_task; | |
11257 | } | |
11258 | ||
79c9ce57 PZ |
11259 | if (task) { |
11260 | err = mutex_lock_interruptible(&task->signal->cred_guard_mutex); | |
11261 | if (err) | |
e5aeee51 | 11262 | goto err_task; |
79c9ce57 PZ |
11263 | |
11264 | /* | |
11265 | * Reuse ptrace permission checks for now. | |
11266 | * | |
11267 | * We must hold cred_guard_mutex across this and any potential | |
11268 | * perf_install_in_context() call for this new event to | |
11269 | * serialize against exec() altering our credentials (and the | |
11270 | * perf_event_exit_task() that could imply). | |
11271 | */ | |
11272 | err = -EACCES; | |
11273 | if (!ptrace_may_access(task, PTRACE_MODE_READ_REALCREDS)) | |
11274 | goto err_cred; | |
11275 | } | |
11276 | ||
79dff51e MF |
11277 | if (flags & PERF_FLAG_PID_CGROUP) |
11278 | cgroup_fd = pid; | |
11279 | ||
4dc0da86 | 11280 | event = perf_event_alloc(&attr, cpu, task, group_leader, NULL, |
79dff51e | 11281 | NULL, NULL, cgroup_fd); |
d14b12d7 SE |
11282 | if (IS_ERR(event)) { |
11283 | err = PTR_ERR(event); | |
79c9ce57 | 11284 | goto err_cred; |
d14b12d7 SE |
11285 | } |
11286 | ||
53b25335 VW |
11287 | if (is_sampling_event(event)) { |
11288 | if (event->pmu->capabilities & PERF_PMU_CAP_NO_INTERRUPT) { | |
a1396555 | 11289 | err = -EOPNOTSUPP; |
53b25335 VW |
11290 | goto err_alloc; |
11291 | } | |
11292 | } | |
11293 | ||
89a1e187 PZ |
11294 | /* |
11295 | * Special case software events and allow them to be part of | |
11296 | * any hardware group. | |
11297 | */ | |
11298 | pmu = event->pmu; | |
b04243ef | 11299 | |
34f43927 PZ |
11300 | if (attr.use_clockid) { |
11301 | err = perf_event_set_clock(event, attr.clockid); | |
11302 | if (err) | |
11303 | goto err_alloc; | |
11304 | } | |
11305 | ||
4ff6a8de DCC |
11306 | if (pmu->task_ctx_nr == perf_sw_context) |
11307 | event->event_caps |= PERF_EV_CAP_SOFTWARE; | |
11308 | ||
a1150c20 SL |
11309 | if (group_leader) { |
11310 | if (is_software_event(event) && | |
11311 | !in_software_context(group_leader)) { | |
b04243ef | 11312 | /* |
a1150c20 SL |
11313 | * If the event is a sw event, but the group_leader |
11314 | * is on hw context. | |
b04243ef | 11315 | * |
a1150c20 SL |
11316 | * Allow the addition of software events to hw |
11317 | * groups, this is safe because software events | |
11318 | * never fail to schedule. | |
b04243ef | 11319 | */ |
a1150c20 SL |
11320 | pmu = group_leader->ctx->pmu; |
11321 | } else if (!is_software_event(event) && | |
11322 | is_software_event(group_leader) && | |
4ff6a8de | 11323 | (group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { |
b04243ef PZ |
11324 | /* |
11325 | * In case the group is a pure software group, and we | |
11326 | * try to add a hardware event, move the whole group to | |
11327 | * the hardware context. | |
11328 | */ | |
11329 | move_group = 1; | |
11330 | } | |
11331 | } | |
89a1e187 PZ |
11332 | |
11333 | /* | |
11334 | * Get the target context (task or percpu): | |
11335 | */ | |
4af57ef2 | 11336 | ctx = find_get_context(pmu, task, event); |
89a1e187 PZ |
11337 | if (IS_ERR(ctx)) { |
11338 | err = PTR_ERR(ctx); | |
c6be5a5c | 11339 | goto err_alloc; |
89a1e187 PZ |
11340 | } |
11341 | ||
ccff286d | 11342 | /* |
cdd6c482 | 11343 | * Look up the group leader (we will attach this event to it): |
04289bb9 | 11344 | */ |
ac9721f3 | 11345 | if (group_leader) { |
dc86cabe | 11346 | err = -EINVAL; |
04289bb9 | 11347 | |
04289bb9 | 11348 | /* |
ccff286d IM |
11349 | * Do not allow a recursive hierarchy (this new sibling |
11350 | * becoming part of another group-sibling): | |
11351 | */ | |
11352 | if (group_leader->group_leader != group_leader) | |
c3f00c70 | 11353 | goto err_context; |
34f43927 PZ |
11354 | |
11355 | /* All events in a group should have the same clock */ | |
11356 | if (group_leader->clock != event->clock) | |
11357 | goto err_context; | |
11358 | ||
ccff286d | 11359 | /* |
64aee2a9 MR |
11360 | * Make sure we're both events for the same CPU; |
11361 | * grouping events for different CPUs is broken; since | |
11362 | * you can never concurrently schedule them anyhow. | |
04289bb9 | 11363 | */ |
64aee2a9 MR |
11364 | if (group_leader->cpu != event->cpu) |
11365 | goto err_context; | |
c3c87e77 | 11366 | |
64aee2a9 MR |
11367 | /* |
11368 | * Make sure we're both on the same task, or both | |
11369 | * per-CPU events. | |
11370 | */ | |
11371 | if (group_leader->ctx->task != ctx->task) | |
11372 | goto err_context; | |
11373 | ||
11374 | /* | |
11375 | * Do not allow to attach to a group in a different task | |
11376 | * or CPU context. If we're moving SW events, we'll fix | |
11377 | * this up later, so allow that. | |
11378 | */ | |
11379 | if (!move_group && group_leader->ctx != ctx) | |
11380 | goto err_context; | |
b04243ef | 11381 | |
3b6f9e5c PM |
11382 | /* |
11383 | * Only a group leader can be exclusive or pinned | |
11384 | */ | |
0d48696f | 11385 | if (attr.exclusive || attr.pinned) |
c3f00c70 | 11386 | goto err_context; |
ac9721f3 PZ |
11387 | } |
11388 | ||
11389 | if (output_event) { | |
11390 | err = perf_event_set_output(event, output_event); | |
11391 | if (err) | |
c3f00c70 | 11392 | goto err_context; |
ac9721f3 | 11393 | } |
0793a61d | 11394 | |
a21b0b35 YD |
11395 | event_file = anon_inode_getfile("[perf_event]", &perf_fops, event, |
11396 | f_flags); | |
ea635c64 AV |
11397 | if (IS_ERR(event_file)) { |
11398 | err = PTR_ERR(event_file); | |
201c2f85 | 11399 | event_file = NULL; |
c3f00c70 | 11400 | goto err_context; |
ea635c64 | 11401 | } |
9b51f66d | 11402 | |
b04243ef | 11403 | if (move_group) { |
321027c1 PZ |
11404 | gctx = __perf_event_ctx_lock_double(group_leader, ctx); |
11405 | ||
84c4e620 PZ |
11406 | if (gctx->task == TASK_TOMBSTONE) { |
11407 | err = -ESRCH; | |
11408 | goto err_locked; | |
11409 | } | |
321027c1 PZ |
11410 | |
11411 | /* | |
11412 | * Check if we raced against another sys_perf_event_open() call | |
11413 | * moving the software group underneath us. | |
11414 | */ | |
11415 | if (!(group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { | |
11416 | /* | |
11417 | * If someone moved the group out from under us, check | |
11418 | * if this new event wound up on the same ctx, if so | |
11419 | * its the regular !move_group case, otherwise fail. | |
11420 | */ | |
11421 | if (gctx != ctx) { | |
11422 | err = -EINVAL; | |
11423 | goto err_locked; | |
11424 | } else { | |
11425 | perf_event_ctx_unlock(group_leader, gctx); | |
11426 | move_group = 0; | |
11427 | } | |
11428 | } | |
8a58ddae AS |
11429 | |
11430 | /* | |
11431 | * Failure to create exclusive events returns -EBUSY. | |
11432 | */ | |
11433 | err = -EBUSY; | |
11434 | if (!exclusive_event_installable(group_leader, ctx)) | |
11435 | goto err_locked; | |
11436 | ||
11437 | for_each_sibling_event(sibling, group_leader) { | |
11438 | if (!exclusive_event_installable(sibling, ctx)) | |
11439 | goto err_locked; | |
11440 | } | |
f55fc2a5 PZ |
11441 | } else { |
11442 | mutex_lock(&ctx->mutex); | |
11443 | } | |
11444 | ||
84c4e620 PZ |
11445 | if (ctx->task == TASK_TOMBSTONE) { |
11446 | err = -ESRCH; | |
11447 | goto err_locked; | |
11448 | } | |
11449 | ||
a723968c PZ |
11450 | if (!perf_event_validate_size(event)) { |
11451 | err = -E2BIG; | |
11452 | goto err_locked; | |
11453 | } | |
11454 | ||
a63fbed7 TG |
11455 | if (!task) { |
11456 | /* | |
11457 | * Check if the @cpu we're creating an event for is online. | |
11458 | * | |
11459 | * We use the perf_cpu_context::ctx::mutex to serialize against | |
11460 | * the hotplug notifiers. See perf_event_{init,exit}_cpu(). | |
11461 | */ | |
11462 | struct perf_cpu_context *cpuctx = | |
11463 | container_of(ctx, struct perf_cpu_context, ctx); | |
11464 | ||
11465 | if (!cpuctx->online) { | |
11466 | err = -ENODEV; | |
11467 | goto err_locked; | |
11468 | } | |
11469 | } | |
11470 | ||
da9ec3d3 MR |
11471 | if (perf_need_aux_event(event) && !perf_get_aux_event(event, group_leader)) { |
11472 | err = -EINVAL; | |
ab43762e | 11473 | goto err_locked; |
da9ec3d3 | 11474 | } |
a63fbed7 | 11475 | |
f55fc2a5 PZ |
11476 | /* |
11477 | * Must be under the same ctx::mutex as perf_install_in_context(), | |
11478 | * because we need to serialize with concurrent event creation. | |
11479 | */ | |
11480 | if (!exclusive_event_installable(event, ctx)) { | |
f55fc2a5 PZ |
11481 | err = -EBUSY; |
11482 | goto err_locked; | |
11483 | } | |
f63a8daa | 11484 | |
f55fc2a5 PZ |
11485 | WARN_ON_ONCE(ctx->parent_ctx); |
11486 | ||
79c9ce57 PZ |
11487 | /* |
11488 | * This is the point on no return; we cannot fail hereafter. This is | |
11489 | * where we start modifying current state. | |
11490 | */ | |
11491 | ||
f55fc2a5 | 11492 | if (move_group) { |
f63a8daa PZ |
11493 | /* |
11494 | * See perf_event_ctx_lock() for comments on the details | |
11495 | * of swizzling perf_event::ctx. | |
11496 | */ | |
45a0e07a | 11497 | perf_remove_from_context(group_leader, 0); |
279b5165 | 11498 | put_ctx(gctx); |
0231bb53 | 11499 | |
edb39592 | 11500 | for_each_sibling_event(sibling, group_leader) { |
45a0e07a | 11501 | perf_remove_from_context(sibling, 0); |
b04243ef PZ |
11502 | put_ctx(gctx); |
11503 | } | |
b04243ef | 11504 | |
f63a8daa PZ |
11505 | /* |
11506 | * Wait for everybody to stop referencing the events through | |
11507 | * the old lists, before installing it on new lists. | |
11508 | */ | |
0cda4c02 | 11509 | synchronize_rcu(); |
f63a8daa | 11510 | |
8f95b435 PZI |
11511 | /* |
11512 | * Install the group siblings before the group leader. | |
11513 | * | |
11514 | * Because a group leader will try and install the entire group | |
11515 | * (through the sibling list, which is still in-tact), we can | |
11516 | * end up with siblings installed in the wrong context. | |
11517 | * | |
11518 | * By installing siblings first we NO-OP because they're not | |
11519 | * reachable through the group lists. | |
11520 | */ | |
edb39592 | 11521 | for_each_sibling_event(sibling, group_leader) { |
8f95b435 | 11522 | perf_event__state_init(sibling); |
9fc81d87 | 11523 | perf_install_in_context(ctx, sibling, sibling->cpu); |
b04243ef PZ |
11524 | get_ctx(ctx); |
11525 | } | |
8f95b435 PZI |
11526 | |
11527 | /* | |
11528 | * Removing from the context ends up with disabled | |
11529 | * event. What we want here is event in the initial | |
11530 | * startup state, ready to be add into new context. | |
11531 | */ | |
11532 | perf_event__state_init(group_leader); | |
11533 | perf_install_in_context(ctx, group_leader, group_leader->cpu); | |
11534 | get_ctx(ctx); | |
bed5b25a AS |
11535 | } |
11536 | ||
f73e22ab PZ |
11537 | /* |
11538 | * Precalculate sample_data sizes; do while holding ctx::mutex such | |
11539 | * that we're serialized against further additions and before | |
11540 | * perf_install_in_context() which is the point the event is active and | |
11541 | * can use these values. | |
11542 | */ | |
11543 | perf_event__header_size(event); | |
11544 | perf_event__id_header_size(event); | |
11545 | ||
78cd2c74 PZ |
11546 | event->owner = current; |
11547 | ||
e2d37cd2 | 11548 | perf_install_in_context(ctx, event, event->cpu); |
fe4b04fa | 11549 | perf_unpin_context(ctx); |
f63a8daa | 11550 | |
f55fc2a5 | 11551 | if (move_group) |
321027c1 | 11552 | perf_event_ctx_unlock(group_leader, gctx); |
d859e29f | 11553 | mutex_unlock(&ctx->mutex); |
9b51f66d | 11554 | |
79c9ce57 PZ |
11555 | if (task) { |
11556 | mutex_unlock(&task->signal->cred_guard_mutex); | |
11557 | put_task_struct(task); | |
11558 | } | |
11559 | ||
cdd6c482 IM |
11560 | mutex_lock(¤t->perf_event_mutex); |
11561 | list_add_tail(&event->owner_entry, ¤t->perf_event_list); | |
11562 | mutex_unlock(¤t->perf_event_mutex); | |
082ff5a2 | 11563 | |
8a49542c PZ |
11564 | /* |
11565 | * Drop the reference on the group_event after placing the | |
11566 | * new event on the sibling_list. This ensures destruction | |
11567 | * of the group leader will find the pointer to itself in | |
11568 | * perf_group_detach(). | |
11569 | */ | |
2903ff01 | 11570 | fdput(group); |
ea635c64 AV |
11571 | fd_install(event_fd, event_file); |
11572 | return event_fd; | |
0793a61d | 11573 | |
f55fc2a5 PZ |
11574 | err_locked: |
11575 | if (move_group) | |
321027c1 | 11576 | perf_event_ctx_unlock(group_leader, gctx); |
f55fc2a5 PZ |
11577 | mutex_unlock(&ctx->mutex); |
11578 | /* err_file: */ | |
11579 | fput(event_file); | |
c3f00c70 | 11580 | err_context: |
fe4b04fa | 11581 | perf_unpin_context(ctx); |
ea635c64 | 11582 | put_ctx(ctx); |
c6be5a5c | 11583 | err_alloc: |
13005627 PZ |
11584 | /* |
11585 | * If event_file is set, the fput() above will have called ->release() | |
11586 | * and that will take care of freeing the event. | |
11587 | */ | |
11588 | if (!event_file) | |
11589 | free_event(event); | |
79c9ce57 PZ |
11590 | err_cred: |
11591 | if (task) | |
11592 | mutex_unlock(&task->signal->cred_guard_mutex); | |
1f4ee503 | 11593 | err_task: |
e7d0bc04 PZ |
11594 | if (task) |
11595 | put_task_struct(task); | |
89a1e187 | 11596 | err_group_fd: |
2903ff01 | 11597 | fdput(group); |
ea635c64 AV |
11598 | err_fd: |
11599 | put_unused_fd(event_fd); | |
dc86cabe | 11600 | return err; |
0793a61d TG |
11601 | } |
11602 | ||
fb0459d7 AV |
11603 | /** |
11604 | * perf_event_create_kernel_counter | |
11605 | * | |
11606 | * @attr: attributes of the counter to create | |
11607 | * @cpu: cpu in which the counter is bound | |
38a81da2 | 11608 | * @task: task to profile (NULL for percpu) |
fb0459d7 AV |
11609 | */ |
11610 | struct perf_event * | |
11611 | perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, | |
38a81da2 | 11612 | struct task_struct *task, |
4dc0da86 AK |
11613 | perf_overflow_handler_t overflow_handler, |
11614 | void *context) | |
fb0459d7 | 11615 | { |
fb0459d7 | 11616 | struct perf_event_context *ctx; |
c3f00c70 | 11617 | struct perf_event *event; |
fb0459d7 | 11618 | int err; |
d859e29f | 11619 | |
dce5affb AS |
11620 | /* |
11621 | * Grouping is not supported for kernel events, neither is 'AUX', | |
11622 | * make sure the caller's intentions are adjusted. | |
11623 | */ | |
11624 | if (attr->aux_output) | |
11625 | return ERR_PTR(-EINVAL); | |
11626 | ||
4dc0da86 | 11627 | event = perf_event_alloc(attr, cpu, task, NULL, NULL, |
79dff51e | 11628 | overflow_handler, context, -1); |
c3f00c70 PZ |
11629 | if (IS_ERR(event)) { |
11630 | err = PTR_ERR(event); | |
11631 | goto err; | |
11632 | } | |
d859e29f | 11633 | |
f8697762 | 11634 | /* Mark owner so we could distinguish it from user events. */ |
63b6da39 | 11635 | event->owner = TASK_TOMBSTONE; |
f8697762 | 11636 | |
f25d8ba9 AS |
11637 | /* |
11638 | * Get the target context (task or percpu): | |
11639 | */ | |
4af57ef2 | 11640 | ctx = find_get_context(event->pmu, task, event); |
c6567f64 FW |
11641 | if (IS_ERR(ctx)) { |
11642 | err = PTR_ERR(ctx); | |
c3f00c70 | 11643 | goto err_free; |
d859e29f | 11644 | } |
fb0459d7 | 11645 | |
fb0459d7 AV |
11646 | WARN_ON_ONCE(ctx->parent_ctx); |
11647 | mutex_lock(&ctx->mutex); | |
84c4e620 PZ |
11648 | if (ctx->task == TASK_TOMBSTONE) { |
11649 | err = -ESRCH; | |
11650 | goto err_unlock; | |
11651 | } | |
11652 | ||
a63fbed7 TG |
11653 | if (!task) { |
11654 | /* | |
11655 | * Check if the @cpu we're creating an event for is online. | |
11656 | * | |
11657 | * We use the perf_cpu_context::ctx::mutex to serialize against | |
11658 | * the hotplug notifiers. See perf_event_{init,exit}_cpu(). | |
11659 | */ | |
11660 | struct perf_cpu_context *cpuctx = | |
11661 | container_of(ctx, struct perf_cpu_context, ctx); | |
11662 | if (!cpuctx->online) { | |
11663 | err = -ENODEV; | |
11664 | goto err_unlock; | |
11665 | } | |
11666 | } | |
11667 | ||
bed5b25a | 11668 | if (!exclusive_event_installable(event, ctx)) { |
bed5b25a | 11669 | err = -EBUSY; |
84c4e620 | 11670 | goto err_unlock; |
bed5b25a AS |
11671 | } |
11672 | ||
4ce54af8 | 11673 | perf_install_in_context(ctx, event, event->cpu); |
fe4b04fa | 11674 | perf_unpin_context(ctx); |
fb0459d7 AV |
11675 | mutex_unlock(&ctx->mutex); |
11676 | ||
fb0459d7 AV |
11677 | return event; |
11678 | ||
84c4e620 PZ |
11679 | err_unlock: |
11680 | mutex_unlock(&ctx->mutex); | |
11681 | perf_unpin_context(ctx); | |
11682 | put_ctx(ctx); | |
c3f00c70 PZ |
11683 | err_free: |
11684 | free_event(event); | |
11685 | err: | |
c6567f64 | 11686 | return ERR_PTR(err); |
9b51f66d | 11687 | } |
fb0459d7 | 11688 | EXPORT_SYMBOL_GPL(perf_event_create_kernel_counter); |
9b51f66d | 11689 | |
0cda4c02 YZ |
11690 | void perf_pmu_migrate_context(struct pmu *pmu, int src_cpu, int dst_cpu) |
11691 | { | |
11692 | struct perf_event_context *src_ctx; | |
11693 | struct perf_event_context *dst_ctx; | |
11694 | struct perf_event *event, *tmp; | |
11695 | LIST_HEAD(events); | |
11696 | ||
11697 | src_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, src_cpu)->ctx; | |
11698 | dst_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, dst_cpu)->ctx; | |
11699 | ||
f63a8daa PZ |
11700 | /* |
11701 | * See perf_event_ctx_lock() for comments on the details | |
11702 | * of swizzling perf_event::ctx. | |
11703 | */ | |
11704 | mutex_lock_double(&src_ctx->mutex, &dst_ctx->mutex); | |
0cda4c02 YZ |
11705 | list_for_each_entry_safe(event, tmp, &src_ctx->event_list, |
11706 | event_entry) { | |
45a0e07a | 11707 | perf_remove_from_context(event, 0); |
9a545de0 | 11708 | unaccount_event_cpu(event, src_cpu); |
0cda4c02 | 11709 | put_ctx(src_ctx); |
9886167d | 11710 | list_add(&event->migrate_entry, &events); |
0cda4c02 | 11711 | } |
0cda4c02 | 11712 | |
8f95b435 PZI |
11713 | /* |
11714 | * Wait for the events to quiesce before re-instating them. | |
11715 | */ | |
0cda4c02 YZ |
11716 | synchronize_rcu(); |
11717 | ||
8f95b435 PZI |
11718 | /* |
11719 | * Re-instate events in 2 passes. | |
11720 | * | |
11721 | * Skip over group leaders and only install siblings on this first | |
11722 | * pass, siblings will not get enabled without a leader, however a | |
11723 | * leader will enable its siblings, even if those are still on the old | |
11724 | * context. | |
11725 | */ | |
11726 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { | |
11727 | if (event->group_leader == event) | |
11728 | continue; | |
11729 | ||
11730 | list_del(&event->migrate_entry); | |
11731 | if (event->state >= PERF_EVENT_STATE_OFF) | |
11732 | event->state = PERF_EVENT_STATE_INACTIVE; | |
11733 | account_event_cpu(event, dst_cpu); | |
11734 | perf_install_in_context(dst_ctx, event, dst_cpu); | |
11735 | get_ctx(dst_ctx); | |
11736 | } | |
11737 | ||
11738 | /* | |
11739 | * Once all the siblings are setup properly, install the group leaders | |
11740 | * to make it go. | |
11741 | */ | |
9886167d PZ |
11742 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { |
11743 | list_del(&event->migrate_entry); | |
0cda4c02 YZ |
11744 | if (event->state >= PERF_EVENT_STATE_OFF) |
11745 | event->state = PERF_EVENT_STATE_INACTIVE; | |
9a545de0 | 11746 | account_event_cpu(event, dst_cpu); |
0cda4c02 YZ |
11747 | perf_install_in_context(dst_ctx, event, dst_cpu); |
11748 | get_ctx(dst_ctx); | |
11749 | } | |
11750 | mutex_unlock(&dst_ctx->mutex); | |
f63a8daa | 11751 | mutex_unlock(&src_ctx->mutex); |
0cda4c02 YZ |
11752 | } |
11753 | EXPORT_SYMBOL_GPL(perf_pmu_migrate_context); | |
11754 | ||
cdd6c482 | 11755 | static void sync_child_event(struct perf_event *child_event, |
38b200d6 | 11756 | struct task_struct *child) |
d859e29f | 11757 | { |
cdd6c482 | 11758 | struct perf_event *parent_event = child_event->parent; |
8bc20959 | 11759 | u64 child_val; |
d859e29f | 11760 | |
cdd6c482 IM |
11761 | if (child_event->attr.inherit_stat) |
11762 | perf_event_read_event(child_event, child); | |
38b200d6 | 11763 | |
b5e58793 | 11764 | child_val = perf_event_count(child_event); |
d859e29f PM |
11765 | |
11766 | /* | |
11767 | * Add back the child's count to the parent's count: | |
11768 | */ | |
a6e6dea6 | 11769 | atomic64_add(child_val, &parent_event->child_count); |
cdd6c482 IM |
11770 | atomic64_add(child_event->total_time_enabled, |
11771 | &parent_event->child_total_time_enabled); | |
11772 | atomic64_add(child_event->total_time_running, | |
11773 | &parent_event->child_total_time_running); | |
d859e29f PM |
11774 | } |
11775 | ||
9b51f66d | 11776 | static void |
8ba289b8 PZ |
11777 | perf_event_exit_event(struct perf_event *child_event, |
11778 | struct perf_event_context *child_ctx, | |
11779 | struct task_struct *child) | |
9b51f66d | 11780 | { |
8ba289b8 PZ |
11781 | struct perf_event *parent_event = child_event->parent; |
11782 | ||
1903d50c PZ |
11783 | /* |
11784 | * Do not destroy the 'original' grouping; because of the context | |
11785 | * switch optimization the original events could've ended up in a | |
11786 | * random child task. | |
11787 | * | |
11788 | * If we were to destroy the original group, all group related | |
11789 | * operations would cease to function properly after this random | |
11790 | * child dies. | |
11791 | * | |
11792 | * Do destroy all inherited groups, we don't care about those | |
11793 | * and being thorough is better. | |
11794 | */ | |
32132a3d PZ |
11795 | raw_spin_lock_irq(&child_ctx->lock); |
11796 | WARN_ON_ONCE(child_ctx->is_active); | |
11797 | ||
8ba289b8 | 11798 | if (parent_event) |
32132a3d PZ |
11799 | perf_group_detach(child_event); |
11800 | list_del_event(child_event, child_ctx); | |
0d3d73aa | 11801 | perf_event_set_state(child_event, PERF_EVENT_STATE_EXIT); /* is_event_hup() */ |
32132a3d | 11802 | raw_spin_unlock_irq(&child_ctx->lock); |
0cc0c027 | 11803 | |
9b51f66d | 11804 | /* |
8ba289b8 | 11805 | * Parent events are governed by their filedesc, retain them. |
9b51f66d | 11806 | */ |
8ba289b8 | 11807 | if (!parent_event) { |
179033b3 | 11808 | perf_event_wakeup(child_event); |
8ba289b8 | 11809 | return; |
4bcf349a | 11810 | } |
8ba289b8 PZ |
11811 | /* |
11812 | * Child events can be cleaned up. | |
11813 | */ | |
11814 | ||
11815 | sync_child_event(child_event, child); | |
11816 | ||
11817 | /* | |
11818 | * Remove this event from the parent's list | |
11819 | */ | |
11820 | WARN_ON_ONCE(parent_event->ctx->parent_ctx); | |
11821 | mutex_lock(&parent_event->child_mutex); | |
11822 | list_del_init(&child_event->child_list); | |
11823 | mutex_unlock(&parent_event->child_mutex); | |
11824 | ||
11825 | /* | |
11826 | * Kick perf_poll() for is_event_hup(). | |
11827 | */ | |
11828 | perf_event_wakeup(parent_event); | |
11829 | free_event(child_event); | |
11830 | put_event(parent_event); | |
9b51f66d IM |
11831 | } |
11832 | ||
8dc85d54 | 11833 | static void perf_event_exit_task_context(struct task_struct *child, int ctxn) |
9b51f66d | 11834 | { |
211de6eb | 11835 | struct perf_event_context *child_ctx, *clone_ctx = NULL; |
63b6da39 | 11836 | struct perf_event *child_event, *next; |
63b6da39 PZ |
11837 | |
11838 | WARN_ON_ONCE(child != current); | |
9b51f66d | 11839 | |
6a3351b6 | 11840 | child_ctx = perf_pin_task_context(child, ctxn); |
63b6da39 | 11841 | if (!child_ctx) |
9b51f66d IM |
11842 | return; |
11843 | ||
ad3a37de | 11844 | /* |
6a3351b6 PZ |
11845 | * In order to reduce the amount of tricky in ctx tear-down, we hold |
11846 | * ctx::mutex over the entire thing. This serializes against almost | |
11847 | * everything that wants to access the ctx. | |
11848 | * | |
11849 | * The exception is sys_perf_event_open() / | |
11850 | * perf_event_create_kernel_count() which does find_get_context() | |
11851 | * without ctx::mutex (it cannot because of the move_group double mutex | |
11852 | * lock thing). See the comments in perf_install_in_context(). | |
ad3a37de | 11853 | */ |
6a3351b6 | 11854 | mutex_lock(&child_ctx->mutex); |
c93f7669 PM |
11855 | |
11856 | /* | |
6a3351b6 PZ |
11857 | * In a single ctx::lock section, de-schedule the events and detach the |
11858 | * context from the task such that we cannot ever get it scheduled back | |
11859 | * in. | |
c93f7669 | 11860 | */ |
6a3351b6 | 11861 | raw_spin_lock_irq(&child_ctx->lock); |
487f05e1 | 11862 | task_ctx_sched_out(__get_cpu_context(child_ctx), child_ctx, EVENT_ALL); |
4a1c0f26 | 11863 | |
71a851b4 | 11864 | /* |
63b6da39 PZ |
11865 | * Now that the context is inactive, destroy the task <-> ctx relation |
11866 | * and mark the context dead. | |
71a851b4 | 11867 | */ |
63b6da39 PZ |
11868 | RCU_INIT_POINTER(child->perf_event_ctxp[ctxn], NULL); |
11869 | put_ctx(child_ctx); /* cannot be last */ | |
11870 | WRITE_ONCE(child_ctx->task, TASK_TOMBSTONE); | |
11871 | put_task_struct(current); /* cannot be last */ | |
4a1c0f26 | 11872 | |
211de6eb | 11873 | clone_ctx = unclone_ctx(child_ctx); |
6a3351b6 | 11874 | raw_spin_unlock_irq(&child_ctx->lock); |
9f498cc5 | 11875 | |
211de6eb PZ |
11876 | if (clone_ctx) |
11877 | put_ctx(clone_ctx); | |
4a1c0f26 | 11878 | |
9f498cc5 | 11879 | /* |
cdd6c482 IM |
11880 | * Report the task dead after unscheduling the events so that we |
11881 | * won't get any samples after PERF_RECORD_EXIT. We can however still | |
11882 | * get a few PERF_RECORD_READ events. | |
9f498cc5 | 11883 | */ |
cdd6c482 | 11884 | perf_event_task(child, child_ctx, 0); |
a63eaf34 | 11885 | |
ebf905fc | 11886 | list_for_each_entry_safe(child_event, next, &child_ctx->event_list, event_entry) |
8ba289b8 | 11887 | perf_event_exit_event(child_event, child_ctx, child); |
8bc20959 | 11888 | |
a63eaf34 PM |
11889 | mutex_unlock(&child_ctx->mutex); |
11890 | ||
11891 | put_ctx(child_ctx); | |
9b51f66d IM |
11892 | } |
11893 | ||
8dc85d54 PZ |
11894 | /* |
11895 | * When a child task exits, feed back event values to parent events. | |
79c9ce57 PZ |
11896 | * |
11897 | * Can be called with cred_guard_mutex held when called from | |
11898 | * install_exec_creds(). | |
8dc85d54 PZ |
11899 | */ |
11900 | void perf_event_exit_task(struct task_struct *child) | |
11901 | { | |
8882135b | 11902 | struct perf_event *event, *tmp; |
8dc85d54 PZ |
11903 | int ctxn; |
11904 | ||
8882135b PZ |
11905 | mutex_lock(&child->perf_event_mutex); |
11906 | list_for_each_entry_safe(event, tmp, &child->perf_event_list, | |
11907 | owner_entry) { | |
11908 | list_del_init(&event->owner_entry); | |
11909 | ||
11910 | /* | |
11911 | * Ensure the list deletion is visible before we clear | |
11912 | * the owner, closes a race against perf_release() where | |
11913 | * we need to serialize on the owner->perf_event_mutex. | |
11914 | */ | |
f47c02c0 | 11915 | smp_store_release(&event->owner, NULL); |
8882135b PZ |
11916 | } |
11917 | mutex_unlock(&child->perf_event_mutex); | |
11918 | ||
8dc85d54 PZ |
11919 | for_each_task_context_nr(ctxn) |
11920 | perf_event_exit_task_context(child, ctxn); | |
4e93ad60 JO |
11921 | |
11922 | /* | |
11923 | * The perf_event_exit_task_context calls perf_event_task | |
11924 | * with child's task_ctx, which generates EXIT events for | |
11925 | * child contexts and sets child->perf_event_ctxp[] to NULL. | |
11926 | * At this point we need to send EXIT events to cpu contexts. | |
11927 | */ | |
11928 | perf_event_task(child, NULL, 0); | |
8dc85d54 PZ |
11929 | } |
11930 | ||
889ff015 FW |
11931 | static void perf_free_event(struct perf_event *event, |
11932 | struct perf_event_context *ctx) | |
11933 | { | |
11934 | struct perf_event *parent = event->parent; | |
11935 | ||
11936 | if (WARN_ON_ONCE(!parent)) | |
11937 | return; | |
11938 | ||
11939 | mutex_lock(&parent->child_mutex); | |
11940 | list_del_init(&event->child_list); | |
11941 | mutex_unlock(&parent->child_mutex); | |
11942 | ||
a6fa941d | 11943 | put_event(parent); |
889ff015 | 11944 | |
652884fe | 11945 | raw_spin_lock_irq(&ctx->lock); |
8a49542c | 11946 | perf_group_detach(event); |
889ff015 | 11947 | list_del_event(event, ctx); |
652884fe | 11948 | raw_spin_unlock_irq(&ctx->lock); |
889ff015 FW |
11949 | free_event(event); |
11950 | } | |
11951 | ||
bbbee908 | 11952 | /* |
1cf8dfe8 PZ |
11953 | * Free a context as created by inheritance by perf_event_init_task() below, |
11954 | * used by fork() in case of fail. | |
652884fe | 11955 | * |
1cf8dfe8 PZ |
11956 | * Even though the task has never lived, the context and events have been |
11957 | * exposed through the child_list, so we must take care tearing it all down. | |
bbbee908 | 11958 | */ |
cdd6c482 | 11959 | void perf_event_free_task(struct task_struct *task) |
bbbee908 | 11960 | { |
8dc85d54 | 11961 | struct perf_event_context *ctx; |
cdd6c482 | 11962 | struct perf_event *event, *tmp; |
8dc85d54 | 11963 | int ctxn; |
bbbee908 | 11964 | |
8dc85d54 PZ |
11965 | for_each_task_context_nr(ctxn) { |
11966 | ctx = task->perf_event_ctxp[ctxn]; | |
11967 | if (!ctx) | |
11968 | continue; | |
bbbee908 | 11969 | |
8dc85d54 | 11970 | mutex_lock(&ctx->mutex); |
e552a838 PZ |
11971 | raw_spin_lock_irq(&ctx->lock); |
11972 | /* | |
11973 | * Destroy the task <-> ctx relation and mark the context dead. | |
11974 | * | |
11975 | * This is important because even though the task hasn't been | |
11976 | * exposed yet the context has been (through child_list). | |
11977 | */ | |
11978 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], NULL); | |
11979 | WRITE_ONCE(ctx->task, TASK_TOMBSTONE); | |
11980 | put_task_struct(task); /* cannot be last */ | |
11981 | raw_spin_unlock_irq(&ctx->lock); | |
bbbee908 | 11982 | |
15121c78 | 11983 | list_for_each_entry_safe(event, tmp, &ctx->event_list, event_entry) |
8dc85d54 | 11984 | perf_free_event(event, ctx); |
bbbee908 | 11985 | |
8dc85d54 | 11986 | mutex_unlock(&ctx->mutex); |
1cf8dfe8 PZ |
11987 | |
11988 | /* | |
11989 | * perf_event_release_kernel() could've stolen some of our | |
11990 | * child events and still have them on its free_list. In that | |
11991 | * case we must wait for these events to have been freed (in | |
11992 | * particular all their references to this task must've been | |
11993 | * dropped). | |
11994 | * | |
11995 | * Without this copy_process() will unconditionally free this | |
11996 | * task (irrespective of its reference count) and | |
11997 | * _free_event()'s put_task_struct(event->hw.target) will be a | |
11998 | * use-after-free. | |
11999 | * | |
12000 | * Wait for all events to drop their context reference. | |
12001 | */ | |
12002 | wait_var_event(&ctx->refcount, refcount_read(&ctx->refcount) == 1); | |
12003 | put_ctx(ctx); /* must be last */ | |
8dc85d54 | 12004 | } |
889ff015 FW |
12005 | } |
12006 | ||
4e231c79 PZ |
12007 | void perf_event_delayed_put(struct task_struct *task) |
12008 | { | |
12009 | int ctxn; | |
12010 | ||
12011 | for_each_task_context_nr(ctxn) | |
12012 | WARN_ON_ONCE(task->perf_event_ctxp[ctxn]); | |
12013 | } | |
12014 | ||
e03e7ee3 | 12015 | struct file *perf_event_get(unsigned int fd) |
ffe8690c | 12016 | { |
02e5ad97 | 12017 | struct file *file = fget(fd); |
e03e7ee3 AS |
12018 | if (!file) |
12019 | return ERR_PTR(-EBADF); | |
ffe8690c | 12020 | |
e03e7ee3 AS |
12021 | if (file->f_op != &perf_fops) { |
12022 | fput(file); | |
12023 | return ERR_PTR(-EBADF); | |
12024 | } | |
ffe8690c | 12025 | |
e03e7ee3 | 12026 | return file; |
ffe8690c KX |
12027 | } |
12028 | ||
f8d959a5 YS |
12029 | const struct perf_event *perf_get_event(struct file *file) |
12030 | { | |
12031 | if (file->f_op != &perf_fops) | |
12032 | return ERR_PTR(-EINVAL); | |
12033 | ||
12034 | return file->private_data; | |
12035 | } | |
12036 | ||
ffe8690c KX |
12037 | const struct perf_event_attr *perf_event_attrs(struct perf_event *event) |
12038 | { | |
12039 | if (!event) | |
12040 | return ERR_PTR(-EINVAL); | |
12041 | ||
12042 | return &event->attr; | |
12043 | } | |
12044 | ||
97dee4f3 | 12045 | /* |
788faab7 | 12046 | * Inherit an event from parent task to child task. |
d8a8cfc7 PZ |
12047 | * |
12048 | * Returns: | |
12049 | * - valid pointer on success | |
12050 | * - NULL for orphaned events | |
12051 | * - IS_ERR() on error | |
97dee4f3 PZ |
12052 | */ |
12053 | static struct perf_event * | |
12054 | inherit_event(struct perf_event *parent_event, | |
12055 | struct task_struct *parent, | |
12056 | struct perf_event_context *parent_ctx, | |
12057 | struct task_struct *child, | |
12058 | struct perf_event *group_leader, | |
12059 | struct perf_event_context *child_ctx) | |
12060 | { | |
8ca2bd41 | 12061 | enum perf_event_state parent_state = parent_event->state; |
97dee4f3 | 12062 | struct perf_event *child_event; |
cee010ec | 12063 | unsigned long flags; |
97dee4f3 PZ |
12064 | |
12065 | /* | |
12066 | * Instead of creating recursive hierarchies of events, | |
12067 | * we link inherited events back to the original parent, | |
12068 | * which has a filp for sure, which we use as the reference | |
12069 | * count: | |
12070 | */ | |
12071 | if (parent_event->parent) | |
12072 | parent_event = parent_event->parent; | |
12073 | ||
12074 | child_event = perf_event_alloc(&parent_event->attr, | |
12075 | parent_event->cpu, | |
d580ff86 | 12076 | child, |
97dee4f3 | 12077 | group_leader, parent_event, |
79dff51e | 12078 | NULL, NULL, -1); |
97dee4f3 PZ |
12079 | if (IS_ERR(child_event)) |
12080 | return child_event; | |
a6fa941d | 12081 | |
313ccb96 JO |
12082 | |
12083 | if ((child_event->attach_state & PERF_ATTACH_TASK_DATA) && | |
12084 | !child_ctx->task_ctx_data) { | |
12085 | struct pmu *pmu = child_event->pmu; | |
12086 | ||
12087 | child_ctx->task_ctx_data = kzalloc(pmu->task_ctx_size, | |
12088 | GFP_KERNEL); | |
12089 | if (!child_ctx->task_ctx_data) { | |
12090 | free_event(child_event); | |
697d8778 | 12091 | return ERR_PTR(-ENOMEM); |
313ccb96 JO |
12092 | } |
12093 | } | |
12094 | ||
c6e5b732 PZ |
12095 | /* |
12096 | * is_orphaned_event() and list_add_tail(&parent_event->child_list) | |
12097 | * must be under the same lock in order to serialize against | |
12098 | * perf_event_release_kernel(), such that either we must observe | |
12099 | * is_orphaned_event() or they will observe us on the child_list. | |
12100 | */ | |
12101 | mutex_lock(&parent_event->child_mutex); | |
fadfe7be JO |
12102 | if (is_orphaned_event(parent_event) || |
12103 | !atomic_long_inc_not_zero(&parent_event->refcount)) { | |
c6e5b732 | 12104 | mutex_unlock(&parent_event->child_mutex); |
313ccb96 | 12105 | /* task_ctx_data is freed with child_ctx */ |
a6fa941d AV |
12106 | free_event(child_event); |
12107 | return NULL; | |
12108 | } | |
12109 | ||
97dee4f3 PZ |
12110 | get_ctx(child_ctx); |
12111 | ||
12112 | /* | |
12113 | * Make the child state follow the state of the parent event, | |
12114 | * not its attr.disabled bit. We hold the parent's mutex, | |
12115 | * so we won't race with perf_event_{en, dis}able_family. | |
12116 | */ | |
1929def9 | 12117 | if (parent_state >= PERF_EVENT_STATE_INACTIVE) |
97dee4f3 PZ |
12118 | child_event->state = PERF_EVENT_STATE_INACTIVE; |
12119 | else | |
12120 | child_event->state = PERF_EVENT_STATE_OFF; | |
12121 | ||
12122 | if (parent_event->attr.freq) { | |
12123 | u64 sample_period = parent_event->hw.sample_period; | |
12124 | struct hw_perf_event *hwc = &child_event->hw; | |
12125 | ||
12126 | hwc->sample_period = sample_period; | |
12127 | hwc->last_period = sample_period; | |
12128 | ||
12129 | local64_set(&hwc->period_left, sample_period); | |
12130 | } | |
12131 | ||
12132 | child_event->ctx = child_ctx; | |
12133 | child_event->overflow_handler = parent_event->overflow_handler; | |
4dc0da86 AK |
12134 | child_event->overflow_handler_context |
12135 | = parent_event->overflow_handler_context; | |
97dee4f3 | 12136 | |
614b6780 TG |
12137 | /* |
12138 | * Precalculate sample_data sizes | |
12139 | */ | |
12140 | perf_event__header_size(child_event); | |
6844c09d | 12141 | perf_event__id_header_size(child_event); |
614b6780 | 12142 | |
97dee4f3 PZ |
12143 | /* |
12144 | * Link it up in the child's context: | |
12145 | */ | |
cee010ec | 12146 | raw_spin_lock_irqsave(&child_ctx->lock, flags); |
97dee4f3 | 12147 | add_event_to_ctx(child_event, child_ctx); |
cee010ec | 12148 | raw_spin_unlock_irqrestore(&child_ctx->lock, flags); |
97dee4f3 | 12149 | |
97dee4f3 PZ |
12150 | /* |
12151 | * Link this into the parent event's child list | |
12152 | */ | |
97dee4f3 PZ |
12153 | list_add_tail(&child_event->child_list, &parent_event->child_list); |
12154 | mutex_unlock(&parent_event->child_mutex); | |
12155 | ||
12156 | return child_event; | |
12157 | } | |
12158 | ||
d8a8cfc7 PZ |
12159 | /* |
12160 | * Inherits an event group. | |
12161 | * | |
12162 | * This will quietly suppress orphaned events; !inherit_event() is not an error. | |
12163 | * This matches with perf_event_release_kernel() removing all child events. | |
12164 | * | |
12165 | * Returns: | |
12166 | * - 0 on success | |
12167 | * - <0 on error | |
12168 | */ | |
97dee4f3 PZ |
12169 | static int inherit_group(struct perf_event *parent_event, |
12170 | struct task_struct *parent, | |
12171 | struct perf_event_context *parent_ctx, | |
12172 | struct task_struct *child, | |
12173 | struct perf_event_context *child_ctx) | |
12174 | { | |
12175 | struct perf_event *leader; | |
12176 | struct perf_event *sub; | |
12177 | struct perf_event *child_ctr; | |
12178 | ||
12179 | leader = inherit_event(parent_event, parent, parent_ctx, | |
12180 | child, NULL, child_ctx); | |
12181 | if (IS_ERR(leader)) | |
12182 | return PTR_ERR(leader); | |
d8a8cfc7 PZ |
12183 | /* |
12184 | * @leader can be NULL here because of is_orphaned_event(). In this | |
12185 | * case inherit_event() will create individual events, similar to what | |
12186 | * perf_group_detach() would do anyway. | |
12187 | */ | |
edb39592 | 12188 | for_each_sibling_event(sub, parent_event) { |
97dee4f3 PZ |
12189 | child_ctr = inherit_event(sub, parent, parent_ctx, |
12190 | child, leader, child_ctx); | |
12191 | if (IS_ERR(child_ctr)) | |
12192 | return PTR_ERR(child_ctr); | |
f733c6b5 | 12193 | |
00496fe5 | 12194 | if (sub->aux_event == parent_event && child_ctr && |
f733c6b5 AS |
12195 | !perf_get_aux_event(child_ctr, leader)) |
12196 | return -EINVAL; | |
97dee4f3 PZ |
12197 | } |
12198 | return 0; | |
889ff015 FW |
12199 | } |
12200 | ||
d8a8cfc7 PZ |
12201 | /* |
12202 | * Creates the child task context and tries to inherit the event-group. | |
12203 | * | |
12204 | * Clears @inherited_all on !attr.inherited or error. Note that we'll leave | |
12205 | * inherited_all set when we 'fail' to inherit an orphaned event; this is | |
12206 | * consistent with perf_event_release_kernel() removing all child events. | |
12207 | * | |
12208 | * Returns: | |
12209 | * - 0 on success | |
12210 | * - <0 on error | |
12211 | */ | |
889ff015 FW |
12212 | static int |
12213 | inherit_task_group(struct perf_event *event, struct task_struct *parent, | |
12214 | struct perf_event_context *parent_ctx, | |
8dc85d54 | 12215 | struct task_struct *child, int ctxn, |
889ff015 FW |
12216 | int *inherited_all) |
12217 | { | |
12218 | int ret; | |
8dc85d54 | 12219 | struct perf_event_context *child_ctx; |
889ff015 FW |
12220 | |
12221 | if (!event->attr.inherit) { | |
12222 | *inherited_all = 0; | |
12223 | return 0; | |
bbbee908 PZ |
12224 | } |
12225 | ||
fe4b04fa | 12226 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 FW |
12227 | if (!child_ctx) { |
12228 | /* | |
12229 | * This is executed from the parent task context, so | |
12230 | * inherit events that have been marked for cloning. | |
12231 | * First allocate and initialize a context for the | |
12232 | * child. | |
12233 | */ | |
734df5ab | 12234 | child_ctx = alloc_perf_context(parent_ctx->pmu, child); |
889ff015 FW |
12235 | if (!child_ctx) |
12236 | return -ENOMEM; | |
bbbee908 | 12237 | |
8dc85d54 | 12238 | child->perf_event_ctxp[ctxn] = child_ctx; |
889ff015 FW |
12239 | } |
12240 | ||
12241 | ret = inherit_group(event, parent, parent_ctx, | |
12242 | child, child_ctx); | |
12243 | ||
12244 | if (ret) | |
12245 | *inherited_all = 0; | |
12246 | ||
12247 | return ret; | |
bbbee908 PZ |
12248 | } |
12249 | ||
9b51f66d | 12250 | /* |
cdd6c482 | 12251 | * Initialize the perf_event context in task_struct |
9b51f66d | 12252 | */ |
985c8dcb | 12253 | static int perf_event_init_context(struct task_struct *child, int ctxn) |
9b51f66d | 12254 | { |
889ff015 | 12255 | struct perf_event_context *child_ctx, *parent_ctx; |
cdd6c482 IM |
12256 | struct perf_event_context *cloned_ctx; |
12257 | struct perf_event *event; | |
9b51f66d | 12258 | struct task_struct *parent = current; |
564c2b21 | 12259 | int inherited_all = 1; |
dddd3379 | 12260 | unsigned long flags; |
6ab423e0 | 12261 | int ret = 0; |
9b51f66d | 12262 | |
8dc85d54 | 12263 | if (likely(!parent->perf_event_ctxp[ctxn])) |
6ab423e0 PZ |
12264 | return 0; |
12265 | ||
ad3a37de | 12266 | /* |
25346b93 PM |
12267 | * If the parent's context is a clone, pin it so it won't get |
12268 | * swapped under us. | |
ad3a37de | 12269 | */ |
8dc85d54 | 12270 | parent_ctx = perf_pin_task_context(parent, ctxn); |
ffb4ef21 PZ |
12271 | if (!parent_ctx) |
12272 | return 0; | |
25346b93 | 12273 | |
ad3a37de PM |
12274 | /* |
12275 | * No need to check if parent_ctx != NULL here; since we saw | |
12276 | * it non-NULL earlier, the only reason for it to become NULL | |
12277 | * is if we exit, and since we're currently in the middle of | |
12278 | * a fork we can't be exiting at the same time. | |
12279 | */ | |
ad3a37de | 12280 | |
9b51f66d IM |
12281 | /* |
12282 | * Lock the parent list. No need to lock the child - not PID | |
12283 | * hashed yet and not running, so nobody can access it. | |
12284 | */ | |
d859e29f | 12285 | mutex_lock(&parent_ctx->mutex); |
9b51f66d IM |
12286 | |
12287 | /* | |
12288 | * We dont have to disable NMIs - we are only looking at | |
12289 | * the list, not manipulating it: | |
12290 | */ | |
6e6804d2 | 12291 | perf_event_groups_for_each(event, &parent_ctx->pinned_groups) { |
8dc85d54 PZ |
12292 | ret = inherit_task_group(event, parent, parent_ctx, |
12293 | child, ctxn, &inherited_all); | |
889ff015 | 12294 | if (ret) |
e7cc4865 | 12295 | goto out_unlock; |
889ff015 | 12296 | } |
b93f7978 | 12297 | |
dddd3379 TG |
12298 | /* |
12299 | * We can't hold ctx->lock when iterating the ->flexible_group list due | |
12300 | * to allocations, but we need to prevent rotation because | |
12301 | * rotate_ctx() will change the list from interrupt context. | |
12302 | */ | |
12303 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); | |
12304 | parent_ctx->rotate_disable = 1; | |
12305 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); | |
12306 | ||
6e6804d2 | 12307 | perf_event_groups_for_each(event, &parent_ctx->flexible_groups) { |
8dc85d54 PZ |
12308 | ret = inherit_task_group(event, parent, parent_ctx, |
12309 | child, ctxn, &inherited_all); | |
889ff015 | 12310 | if (ret) |
e7cc4865 | 12311 | goto out_unlock; |
564c2b21 PM |
12312 | } |
12313 | ||
dddd3379 TG |
12314 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); |
12315 | parent_ctx->rotate_disable = 0; | |
dddd3379 | 12316 | |
8dc85d54 | 12317 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 | 12318 | |
05cbaa28 | 12319 | if (child_ctx && inherited_all) { |
564c2b21 PM |
12320 | /* |
12321 | * Mark the child context as a clone of the parent | |
12322 | * context, or of whatever the parent is a clone of. | |
c5ed5145 PZ |
12323 | * |
12324 | * Note that if the parent is a clone, the holding of | |
12325 | * parent_ctx->lock avoids it from being uncloned. | |
564c2b21 | 12326 | */ |
c5ed5145 | 12327 | cloned_ctx = parent_ctx->parent_ctx; |
ad3a37de PM |
12328 | if (cloned_ctx) { |
12329 | child_ctx->parent_ctx = cloned_ctx; | |
25346b93 | 12330 | child_ctx->parent_gen = parent_ctx->parent_gen; |
564c2b21 PM |
12331 | } else { |
12332 | child_ctx->parent_ctx = parent_ctx; | |
12333 | child_ctx->parent_gen = parent_ctx->generation; | |
12334 | } | |
12335 | get_ctx(child_ctx->parent_ctx); | |
9b51f66d IM |
12336 | } |
12337 | ||
c5ed5145 | 12338 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); |
e7cc4865 | 12339 | out_unlock: |
d859e29f | 12340 | mutex_unlock(&parent_ctx->mutex); |
6ab423e0 | 12341 | |
25346b93 | 12342 | perf_unpin_context(parent_ctx); |
fe4b04fa | 12343 | put_ctx(parent_ctx); |
ad3a37de | 12344 | |
6ab423e0 | 12345 | return ret; |
9b51f66d IM |
12346 | } |
12347 | ||
8dc85d54 PZ |
12348 | /* |
12349 | * Initialize the perf_event context in task_struct | |
12350 | */ | |
12351 | int perf_event_init_task(struct task_struct *child) | |
12352 | { | |
12353 | int ctxn, ret; | |
12354 | ||
8550d7cb ON |
12355 | memset(child->perf_event_ctxp, 0, sizeof(child->perf_event_ctxp)); |
12356 | mutex_init(&child->perf_event_mutex); | |
12357 | INIT_LIST_HEAD(&child->perf_event_list); | |
12358 | ||
8dc85d54 PZ |
12359 | for_each_task_context_nr(ctxn) { |
12360 | ret = perf_event_init_context(child, ctxn); | |
6c72e350 PZ |
12361 | if (ret) { |
12362 | perf_event_free_task(child); | |
8dc85d54 | 12363 | return ret; |
6c72e350 | 12364 | } |
8dc85d54 PZ |
12365 | } |
12366 | ||
12367 | return 0; | |
12368 | } | |
12369 | ||
220b140b PM |
12370 | static void __init perf_event_init_all_cpus(void) |
12371 | { | |
b28ab83c | 12372 | struct swevent_htable *swhash; |
220b140b | 12373 | int cpu; |
220b140b | 12374 | |
a63fbed7 TG |
12375 | zalloc_cpumask_var(&perf_online_mask, GFP_KERNEL); |
12376 | ||
220b140b | 12377 | for_each_possible_cpu(cpu) { |
b28ab83c PZ |
12378 | swhash = &per_cpu(swevent_htable, cpu); |
12379 | mutex_init(&swhash->hlist_mutex); | |
2fde4f94 | 12380 | INIT_LIST_HEAD(&per_cpu(active_ctx_list, cpu)); |
f2fb6bef KL |
12381 | |
12382 | INIT_LIST_HEAD(&per_cpu(pmu_sb_events.list, cpu)); | |
12383 | raw_spin_lock_init(&per_cpu(pmu_sb_events.lock, cpu)); | |
e48c1788 | 12384 | |
058fe1c0 DCC |
12385 | #ifdef CONFIG_CGROUP_PERF |
12386 | INIT_LIST_HEAD(&per_cpu(cgrp_cpuctx_list, cpu)); | |
12387 | #endif | |
e48c1788 | 12388 | INIT_LIST_HEAD(&per_cpu(sched_cb_list, cpu)); |
220b140b PM |
12389 | } |
12390 | } | |
12391 | ||
d18bf422 | 12392 | static void perf_swevent_init_cpu(unsigned int cpu) |
0793a61d | 12393 | { |
108b02cf | 12394 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
0793a61d | 12395 | |
b28ab83c | 12396 | mutex_lock(&swhash->hlist_mutex); |
059fcd8c | 12397 | if (swhash->hlist_refcount > 0 && !swevent_hlist_deref(swhash)) { |
76e1d904 FW |
12398 | struct swevent_hlist *hlist; |
12399 | ||
b28ab83c PZ |
12400 | hlist = kzalloc_node(sizeof(*hlist), GFP_KERNEL, cpu_to_node(cpu)); |
12401 | WARN_ON(!hlist); | |
12402 | rcu_assign_pointer(swhash->swevent_hlist, hlist); | |
76e1d904 | 12403 | } |
b28ab83c | 12404 | mutex_unlock(&swhash->hlist_mutex); |
0793a61d TG |
12405 | } |
12406 | ||
2965faa5 | 12407 | #if defined CONFIG_HOTPLUG_CPU || defined CONFIG_KEXEC_CORE |
108b02cf | 12408 | static void __perf_event_exit_context(void *__info) |
0793a61d | 12409 | { |
108b02cf | 12410 | struct perf_event_context *ctx = __info; |
fae3fde6 PZ |
12411 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
12412 | struct perf_event *event; | |
0793a61d | 12413 | |
fae3fde6 | 12414 | raw_spin_lock(&ctx->lock); |
0ee098c9 | 12415 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
fae3fde6 | 12416 | list_for_each_entry(event, &ctx->event_list, event_entry) |
45a0e07a | 12417 | __perf_remove_from_context(event, cpuctx, ctx, (void *)DETACH_GROUP); |
fae3fde6 | 12418 | raw_spin_unlock(&ctx->lock); |
0793a61d | 12419 | } |
108b02cf PZ |
12420 | |
12421 | static void perf_event_exit_cpu_context(int cpu) | |
12422 | { | |
a63fbed7 | 12423 | struct perf_cpu_context *cpuctx; |
108b02cf PZ |
12424 | struct perf_event_context *ctx; |
12425 | struct pmu *pmu; | |
108b02cf | 12426 | |
a63fbed7 TG |
12427 | mutex_lock(&pmus_lock); |
12428 | list_for_each_entry(pmu, &pmus, entry) { | |
12429 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
12430 | ctx = &cpuctx->ctx; | |
108b02cf PZ |
12431 | |
12432 | mutex_lock(&ctx->mutex); | |
12433 | smp_call_function_single(cpu, __perf_event_exit_context, ctx, 1); | |
a63fbed7 | 12434 | cpuctx->online = 0; |
108b02cf PZ |
12435 | mutex_unlock(&ctx->mutex); |
12436 | } | |
a63fbed7 TG |
12437 | cpumask_clear_cpu(cpu, perf_online_mask); |
12438 | mutex_unlock(&pmus_lock); | |
108b02cf | 12439 | } |
00e16c3d TG |
12440 | #else |
12441 | ||
12442 | static void perf_event_exit_cpu_context(int cpu) { } | |
12443 | ||
12444 | #endif | |
108b02cf | 12445 | |
a63fbed7 TG |
12446 | int perf_event_init_cpu(unsigned int cpu) |
12447 | { | |
12448 | struct perf_cpu_context *cpuctx; | |
12449 | struct perf_event_context *ctx; | |
12450 | struct pmu *pmu; | |
12451 | ||
12452 | perf_swevent_init_cpu(cpu); | |
12453 | ||
12454 | mutex_lock(&pmus_lock); | |
12455 | cpumask_set_cpu(cpu, perf_online_mask); | |
12456 | list_for_each_entry(pmu, &pmus, entry) { | |
12457 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
12458 | ctx = &cpuctx->ctx; | |
12459 | ||
12460 | mutex_lock(&ctx->mutex); | |
12461 | cpuctx->online = 1; | |
12462 | mutex_unlock(&ctx->mutex); | |
12463 | } | |
12464 | mutex_unlock(&pmus_lock); | |
12465 | ||
12466 | return 0; | |
12467 | } | |
12468 | ||
00e16c3d | 12469 | int perf_event_exit_cpu(unsigned int cpu) |
0793a61d | 12470 | { |
e3703f8c | 12471 | perf_event_exit_cpu_context(cpu); |
00e16c3d | 12472 | return 0; |
0793a61d | 12473 | } |
0793a61d | 12474 | |
c277443c PZ |
12475 | static int |
12476 | perf_reboot(struct notifier_block *notifier, unsigned long val, void *v) | |
12477 | { | |
12478 | int cpu; | |
12479 | ||
12480 | for_each_online_cpu(cpu) | |
12481 | perf_event_exit_cpu(cpu); | |
12482 | ||
12483 | return NOTIFY_OK; | |
12484 | } | |
12485 | ||
12486 | /* | |
12487 | * Run the perf reboot notifier at the very last possible moment so that | |
12488 | * the generic watchdog code runs as long as possible. | |
12489 | */ | |
12490 | static struct notifier_block perf_reboot_notifier = { | |
12491 | .notifier_call = perf_reboot, | |
12492 | .priority = INT_MIN, | |
12493 | }; | |
12494 | ||
cdd6c482 | 12495 | void __init perf_event_init(void) |
0793a61d | 12496 | { |
3c502e7a JW |
12497 | int ret; |
12498 | ||
2e80a82a PZ |
12499 | idr_init(&pmu_idr); |
12500 | ||
220b140b | 12501 | perf_event_init_all_cpus(); |
b0a873eb | 12502 | init_srcu_struct(&pmus_srcu); |
2e80a82a PZ |
12503 | perf_pmu_register(&perf_swevent, "software", PERF_TYPE_SOFTWARE); |
12504 | perf_pmu_register(&perf_cpu_clock, NULL, -1); | |
12505 | perf_pmu_register(&perf_task_clock, NULL, -1); | |
b0a873eb | 12506 | perf_tp_register(); |
00e16c3d | 12507 | perf_event_init_cpu(smp_processor_id()); |
c277443c | 12508 | register_reboot_notifier(&perf_reboot_notifier); |
3c502e7a JW |
12509 | |
12510 | ret = init_hw_breakpoint(); | |
12511 | WARN(ret, "hw_breakpoint initialization failed with: %d", ret); | |
b2029520 | 12512 | |
b01c3a00 JO |
12513 | /* |
12514 | * Build time assertion that we keep the data_head at the intended | |
12515 | * location. IOW, validation we got the __reserved[] size right. | |
12516 | */ | |
12517 | BUILD_BUG_ON((offsetof(struct perf_event_mmap_page, data_head)) | |
12518 | != 1024); | |
0793a61d | 12519 | } |
abe43400 | 12520 | |
fd979c01 CS |
12521 | ssize_t perf_event_sysfs_show(struct device *dev, struct device_attribute *attr, |
12522 | char *page) | |
12523 | { | |
12524 | struct perf_pmu_events_attr *pmu_attr = | |
12525 | container_of(attr, struct perf_pmu_events_attr, attr); | |
12526 | ||
12527 | if (pmu_attr->event_str) | |
12528 | return sprintf(page, "%s\n", pmu_attr->event_str); | |
12529 | ||
12530 | return 0; | |
12531 | } | |
675965b0 | 12532 | EXPORT_SYMBOL_GPL(perf_event_sysfs_show); |
fd979c01 | 12533 | |
abe43400 PZ |
12534 | static int __init perf_event_sysfs_init(void) |
12535 | { | |
12536 | struct pmu *pmu; | |
12537 | int ret; | |
12538 | ||
12539 | mutex_lock(&pmus_lock); | |
12540 | ||
12541 | ret = bus_register(&pmu_bus); | |
12542 | if (ret) | |
12543 | goto unlock; | |
12544 | ||
12545 | list_for_each_entry(pmu, &pmus, entry) { | |
12546 | if (!pmu->name || pmu->type < 0) | |
12547 | continue; | |
12548 | ||
12549 | ret = pmu_dev_alloc(pmu); | |
12550 | WARN(ret, "Failed to register pmu: %s, reason %d\n", pmu->name, ret); | |
12551 | } | |
12552 | pmu_bus_running = 1; | |
12553 | ret = 0; | |
12554 | ||
12555 | unlock: | |
12556 | mutex_unlock(&pmus_lock); | |
12557 | ||
12558 | return ret; | |
12559 | } | |
12560 | device_initcall(perf_event_sysfs_init); | |
e5d1367f SE |
12561 | |
12562 | #ifdef CONFIG_CGROUP_PERF | |
eb95419b TH |
12563 | static struct cgroup_subsys_state * |
12564 | perf_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) | |
e5d1367f SE |
12565 | { |
12566 | struct perf_cgroup *jc; | |
e5d1367f | 12567 | |
1b15d055 | 12568 | jc = kzalloc(sizeof(*jc), GFP_KERNEL); |
e5d1367f SE |
12569 | if (!jc) |
12570 | return ERR_PTR(-ENOMEM); | |
12571 | ||
e5d1367f SE |
12572 | jc->info = alloc_percpu(struct perf_cgroup_info); |
12573 | if (!jc->info) { | |
12574 | kfree(jc); | |
12575 | return ERR_PTR(-ENOMEM); | |
12576 | } | |
12577 | ||
e5d1367f SE |
12578 | return &jc->css; |
12579 | } | |
12580 | ||
eb95419b | 12581 | static void perf_cgroup_css_free(struct cgroup_subsys_state *css) |
e5d1367f | 12582 | { |
eb95419b TH |
12583 | struct perf_cgroup *jc = container_of(css, struct perf_cgroup, css); |
12584 | ||
e5d1367f SE |
12585 | free_percpu(jc->info); |
12586 | kfree(jc); | |
12587 | } | |
12588 | ||
12589 | static int __perf_cgroup_move(void *info) | |
12590 | { | |
12591 | struct task_struct *task = info; | |
ddaaf4e2 | 12592 | rcu_read_lock(); |
e5d1367f | 12593 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT | PERF_CGROUP_SWIN); |
ddaaf4e2 | 12594 | rcu_read_unlock(); |
e5d1367f SE |
12595 | return 0; |
12596 | } | |
12597 | ||
1f7dd3e5 | 12598 | static void perf_cgroup_attach(struct cgroup_taskset *tset) |
e5d1367f | 12599 | { |
bb9d97b6 | 12600 | struct task_struct *task; |
1f7dd3e5 | 12601 | struct cgroup_subsys_state *css; |
bb9d97b6 | 12602 | |
1f7dd3e5 | 12603 | cgroup_taskset_for_each(task, css, tset) |
bb9d97b6 | 12604 | task_function_call(task, __perf_cgroup_move, task); |
e5d1367f SE |
12605 | } |
12606 | ||
073219e9 | 12607 | struct cgroup_subsys perf_event_cgrp_subsys = { |
92fb9748 TH |
12608 | .css_alloc = perf_cgroup_css_alloc, |
12609 | .css_free = perf_cgroup_css_free, | |
bb9d97b6 | 12610 | .attach = perf_cgroup_attach, |
968ebff1 TH |
12611 | /* |
12612 | * Implicitly enable on dfl hierarchy so that perf events can | |
12613 | * always be filtered by cgroup2 path as long as perf_event | |
12614 | * controller is not mounted on a legacy hierarchy. | |
12615 | */ | |
12616 | .implicit_on_dfl = true, | |
8cfd8147 | 12617 | .threaded = true, |
e5d1367f SE |
12618 | }; |
12619 | #endif /* CONFIG_CGROUP_PERF */ |