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, | |
954 | * this will always be called from the right CPU. | |
955 | */ | |
956 | cpuctx = __get_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) | |
982 | list_add(cpuctx_entry, this_cpu_ptr(&cgrp_cpuctx_list)); | |
983 | else | |
984 | list_del(cpuctx_entry); | |
db4a8356 DCC |
985 | } |
986 | ||
e5d1367f SE |
987 | #else /* !CONFIG_CGROUP_PERF */ |
988 | ||
989 | static inline bool | |
990 | perf_cgroup_match(struct perf_event *event) | |
991 | { | |
992 | return true; | |
993 | } | |
994 | ||
995 | static inline void perf_detach_cgroup(struct perf_event *event) | |
996 | {} | |
997 | ||
998 | static inline int is_cgroup_event(struct perf_event *event) | |
999 | { | |
1000 | return 0; | |
1001 | } | |
1002 | ||
e5d1367f SE |
1003 | static inline void update_cgrp_time_from_event(struct perf_event *event) |
1004 | { | |
1005 | } | |
1006 | ||
1007 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
1008 | { | |
1009 | } | |
1010 | ||
a8d757ef SE |
1011 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
1012 | struct task_struct *next) | |
e5d1367f SE |
1013 | { |
1014 | } | |
1015 | ||
a8d757ef SE |
1016 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
1017 | struct task_struct *task) | |
e5d1367f SE |
1018 | { |
1019 | } | |
1020 | ||
1021 | static inline int perf_cgroup_connect(pid_t pid, struct perf_event *event, | |
1022 | struct perf_event_attr *attr, | |
1023 | struct perf_event *group_leader) | |
1024 | { | |
1025 | return -EINVAL; | |
1026 | } | |
1027 | ||
1028 | static inline void | |
3f7cce3c SE |
1029 | perf_cgroup_set_timestamp(struct task_struct *task, |
1030 | struct perf_event_context *ctx) | |
e5d1367f SE |
1031 | { |
1032 | } | |
1033 | ||
d00dbd29 | 1034 | static inline void |
e5d1367f SE |
1035 | perf_cgroup_switch(struct task_struct *task, struct task_struct *next) |
1036 | { | |
1037 | } | |
1038 | ||
1039 | static inline void | |
1040 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
1041 | { | |
1042 | } | |
1043 | ||
1044 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
1045 | { | |
1046 | return 0; | |
1047 | } | |
1048 | ||
db4a8356 DCC |
1049 | static inline void |
1050 | list_update_cgroup_event(struct perf_event *event, | |
1051 | struct perf_event_context *ctx, bool add) | |
1052 | { | |
1053 | } | |
1054 | ||
e5d1367f SE |
1055 | #endif |
1056 | ||
9e630205 SE |
1057 | /* |
1058 | * set default to be dependent on timer tick just | |
1059 | * like original code | |
1060 | */ | |
1061 | #define PERF_CPU_HRTIMER (1000 / HZ) | |
1062 | /* | |
8a1115ff | 1063 | * function must be called with interrupts disabled |
9e630205 | 1064 | */ |
272325c4 | 1065 | static enum hrtimer_restart perf_mux_hrtimer_handler(struct hrtimer *hr) |
9e630205 SE |
1066 | { |
1067 | struct perf_cpu_context *cpuctx; | |
8d5bce0c | 1068 | bool rotations; |
9e630205 | 1069 | |
16444645 | 1070 | lockdep_assert_irqs_disabled(); |
9e630205 SE |
1071 | |
1072 | cpuctx = container_of(hr, struct perf_cpu_context, hrtimer); | |
9e630205 SE |
1073 | rotations = perf_rotate_context(cpuctx); |
1074 | ||
4cfafd30 PZ |
1075 | raw_spin_lock(&cpuctx->hrtimer_lock); |
1076 | if (rotations) | |
9e630205 | 1077 | hrtimer_forward_now(hr, cpuctx->hrtimer_interval); |
4cfafd30 PZ |
1078 | else |
1079 | cpuctx->hrtimer_active = 0; | |
1080 | raw_spin_unlock(&cpuctx->hrtimer_lock); | |
9e630205 | 1081 | |
4cfafd30 | 1082 | return rotations ? HRTIMER_RESTART : HRTIMER_NORESTART; |
9e630205 SE |
1083 | } |
1084 | ||
272325c4 | 1085 | static void __perf_mux_hrtimer_init(struct perf_cpu_context *cpuctx, int cpu) |
9e630205 | 1086 | { |
272325c4 | 1087 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1088 | struct pmu *pmu = cpuctx->ctx.pmu; |
272325c4 | 1089 | u64 interval; |
9e630205 SE |
1090 | |
1091 | /* no multiplexing needed for SW PMU */ | |
1092 | if (pmu->task_ctx_nr == perf_sw_context) | |
1093 | return; | |
1094 | ||
62b85639 SE |
1095 | /* |
1096 | * check default is sane, if not set then force to | |
1097 | * default interval (1/tick) | |
1098 | */ | |
272325c4 PZ |
1099 | interval = pmu->hrtimer_interval_ms; |
1100 | if (interval < 1) | |
1101 | interval = pmu->hrtimer_interval_ms = PERF_CPU_HRTIMER; | |
62b85639 | 1102 | |
272325c4 | 1103 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * interval); |
9e630205 | 1104 | |
4cfafd30 | 1105 | raw_spin_lock_init(&cpuctx->hrtimer_lock); |
30f9028b | 1106 | hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_PINNED_HARD); |
272325c4 | 1107 | timer->function = perf_mux_hrtimer_handler; |
9e630205 SE |
1108 | } |
1109 | ||
272325c4 | 1110 | static int perf_mux_hrtimer_restart(struct perf_cpu_context *cpuctx) |
9e630205 | 1111 | { |
272325c4 | 1112 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1113 | struct pmu *pmu = cpuctx->ctx.pmu; |
4cfafd30 | 1114 | unsigned long flags; |
9e630205 SE |
1115 | |
1116 | /* not for SW PMU */ | |
1117 | if (pmu->task_ctx_nr == perf_sw_context) | |
272325c4 | 1118 | return 0; |
9e630205 | 1119 | |
4cfafd30 PZ |
1120 | raw_spin_lock_irqsave(&cpuctx->hrtimer_lock, flags); |
1121 | if (!cpuctx->hrtimer_active) { | |
1122 | cpuctx->hrtimer_active = 1; | |
1123 | hrtimer_forward_now(timer, cpuctx->hrtimer_interval); | |
30f9028b | 1124 | hrtimer_start_expires(timer, HRTIMER_MODE_ABS_PINNED_HARD); |
4cfafd30 PZ |
1125 | } |
1126 | raw_spin_unlock_irqrestore(&cpuctx->hrtimer_lock, flags); | |
9e630205 | 1127 | |
272325c4 | 1128 | return 0; |
9e630205 SE |
1129 | } |
1130 | ||
33696fc0 | 1131 | void perf_pmu_disable(struct pmu *pmu) |
9e35ad38 | 1132 | { |
33696fc0 PZ |
1133 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1134 | if (!(*count)++) | |
1135 | pmu->pmu_disable(pmu); | |
9e35ad38 | 1136 | } |
9e35ad38 | 1137 | |
33696fc0 | 1138 | void perf_pmu_enable(struct pmu *pmu) |
9e35ad38 | 1139 | { |
33696fc0 PZ |
1140 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1141 | if (!--(*count)) | |
1142 | pmu->pmu_enable(pmu); | |
9e35ad38 | 1143 | } |
9e35ad38 | 1144 | |
2fde4f94 | 1145 | static DEFINE_PER_CPU(struct list_head, active_ctx_list); |
e9d2b064 PZ |
1146 | |
1147 | /* | |
2fde4f94 MR |
1148 | * perf_event_ctx_activate(), perf_event_ctx_deactivate(), and |
1149 | * perf_event_task_tick() are fully serialized because they're strictly cpu | |
1150 | * affine and perf_event_ctx{activate,deactivate} are called with IRQs | |
1151 | * disabled, while perf_event_task_tick is called from IRQ context. | |
e9d2b064 | 1152 | */ |
2fde4f94 | 1153 | static void perf_event_ctx_activate(struct perf_event_context *ctx) |
9e35ad38 | 1154 | { |
2fde4f94 | 1155 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
b5ab4cd5 | 1156 | |
16444645 | 1157 | lockdep_assert_irqs_disabled(); |
b5ab4cd5 | 1158 | |
2fde4f94 MR |
1159 | WARN_ON(!list_empty(&ctx->active_ctx_list)); |
1160 | ||
1161 | list_add(&ctx->active_ctx_list, head); | |
1162 | } | |
1163 | ||
1164 | static void perf_event_ctx_deactivate(struct perf_event_context *ctx) | |
1165 | { | |
16444645 | 1166 | lockdep_assert_irqs_disabled(); |
2fde4f94 MR |
1167 | |
1168 | WARN_ON(list_empty(&ctx->active_ctx_list)); | |
1169 | ||
1170 | list_del_init(&ctx->active_ctx_list); | |
9e35ad38 | 1171 | } |
9e35ad38 | 1172 | |
cdd6c482 | 1173 | static void get_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1174 | { |
8c94abbb | 1175 | refcount_inc(&ctx->refcount); |
a63eaf34 PM |
1176 | } |
1177 | ||
4af57ef2 YZ |
1178 | static void free_ctx(struct rcu_head *head) |
1179 | { | |
1180 | struct perf_event_context *ctx; | |
1181 | ||
1182 | ctx = container_of(head, struct perf_event_context, rcu_head); | |
1183 | kfree(ctx->task_ctx_data); | |
1184 | kfree(ctx); | |
1185 | } | |
1186 | ||
cdd6c482 | 1187 | static void put_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1188 | { |
8c94abbb | 1189 | if (refcount_dec_and_test(&ctx->refcount)) { |
564c2b21 PM |
1190 | if (ctx->parent_ctx) |
1191 | put_ctx(ctx->parent_ctx); | |
63b6da39 | 1192 | if (ctx->task && ctx->task != TASK_TOMBSTONE) |
c93f7669 | 1193 | put_task_struct(ctx->task); |
4af57ef2 | 1194 | call_rcu(&ctx->rcu_head, free_ctx); |
564c2b21 | 1195 | } |
a63eaf34 PM |
1196 | } |
1197 | ||
f63a8daa PZ |
1198 | /* |
1199 | * Because of perf_event::ctx migration in sys_perf_event_open::move_group and | |
1200 | * perf_pmu_migrate_context() we need some magic. | |
1201 | * | |
1202 | * Those places that change perf_event::ctx will hold both | |
1203 | * perf_event_ctx::mutex of the 'old' and 'new' ctx value. | |
1204 | * | |
8b10c5e2 PZ |
1205 | * Lock ordering is by mutex address. There are two other sites where |
1206 | * perf_event_context::mutex nests and those are: | |
1207 | * | |
1208 | * - perf_event_exit_task_context() [ child , 0 ] | |
8ba289b8 PZ |
1209 | * perf_event_exit_event() |
1210 | * put_event() [ parent, 1 ] | |
8b10c5e2 PZ |
1211 | * |
1212 | * - perf_event_init_context() [ parent, 0 ] | |
1213 | * inherit_task_group() | |
1214 | * inherit_group() | |
1215 | * inherit_event() | |
1216 | * perf_event_alloc() | |
1217 | * perf_init_event() | |
1218 | * perf_try_init_event() [ child , 1 ] | |
1219 | * | |
1220 | * While it appears there is an obvious deadlock here -- the parent and child | |
1221 | * nesting levels are inverted between the two. This is in fact safe because | |
1222 | * life-time rules separate them. That is an exiting task cannot fork, and a | |
1223 | * spawning task cannot (yet) exit. | |
1224 | * | |
1225 | * But remember that that these are parent<->child context relations, and | |
1226 | * migration does not affect children, therefore these two orderings should not | |
1227 | * interact. | |
f63a8daa PZ |
1228 | * |
1229 | * The change in perf_event::ctx does not affect children (as claimed above) | |
1230 | * because the sys_perf_event_open() case will install a new event and break | |
1231 | * the ctx parent<->child relation, and perf_pmu_migrate_context() is only | |
1232 | * concerned with cpuctx and that doesn't have children. | |
1233 | * | |
1234 | * The places that change perf_event::ctx will issue: | |
1235 | * | |
1236 | * perf_remove_from_context(); | |
1237 | * synchronize_rcu(); | |
1238 | * perf_install_in_context(); | |
1239 | * | |
1240 | * to affect the change. The remove_from_context() + synchronize_rcu() should | |
1241 | * quiesce the event, after which we can install it in the new location. This | |
1242 | * means that only external vectors (perf_fops, prctl) can perturb the event | |
1243 | * while in transit. Therefore all such accessors should also acquire | |
1244 | * perf_event_context::mutex to serialize against this. | |
1245 | * | |
1246 | * However; because event->ctx can change while we're waiting to acquire | |
1247 | * ctx->mutex we must be careful and use the below perf_event_ctx_lock() | |
1248 | * function. | |
1249 | * | |
1250 | * Lock order: | |
79c9ce57 | 1251 | * cred_guard_mutex |
f63a8daa PZ |
1252 | * task_struct::perf_event_mutex |
1253 | * perf_event_context::mutex | |
f63a8daa | 1254 | * perf_event::child_mutex; |
07c4a776 | 1255 | * perf_event_context::lock |
f63a8daa PZ |
1256 | * perf_event::mmap_mutex |
1257 | * mmap_sem | |
18736eef | 1258 | * perf_addr_filters_head::lock |
82d94856 PZ |
1259 | * |
1260 | * cpu_hotplug_lock | |
1261 | * pmus_lock | |
1262 | * cpuctx->mutex / perf_event_context::mutex | |
f63a8daa | 1263 | */ |
a83fe28e PZ |
1264 | static struct perf_event_context * |
1265 | perf_event_ctx_lock_nested(struct perf_event *event, int nesting) | |
f63a8daa PZ |
1266 | { |
1267 | struct perf_event_context *ctx; | |
1268 | ||
1269 | again: | |
1270 | rcu_read_lock(); | |
6aa7de05 | 1271 | ctx = READ_ONCE(event->ctx); |
8c94abbb | 1272 | if (!refcount_inc_not_zero(&ctx->refcount)) { |
f63a8daa PZ |
1273 | rcu_read_unlock(); |
1274 | goto again; | |
1275 | } | |
1276 | rcu_read_unlock(); | |
1277 | ||
a83fe28e | 1278 | mutex_lock_nested(&ctx->mutex, nesting); |
f63a8daa PZ |
1279 | if (event->ctx != ctx) { |
1280 | mutex_unlock(&ctx->mutex); | |
1281 | put_ctx(ctx); | |
1282 | goto again; | |
1283 | } | |
1284 | ||
1285 | return ctx; | |
1286 | } | |
1287 | ||
a83fe28e PZ |
1288 | static inline struct perf_event_context * |
1289 | perf_event_ctx_lock(struct perf_event *event) | |
1290 | { | |
1291 | return perf_event_ctx_lock_nested(event, 0); | |
1292 | } | |
1293 | ||
f63a8daa PZ |
1294 | static void perf_event_ctx_unlock(struct perf_event *event, |
1295 | struct perf_event_context *ctx) | |
1296 | { | |
1297 | mutex_unlock(&ctx->mutex); | |
1298 | put_ctx(ctx); | |
1299 | } | |
1300 | ||
211de6eb PZ |
1301 | /* |
1302 | * This must be done under the ctx->lock, such as to serialize against | |
1303 | * context_equiv(), therefore we cannot call put_ctx() since that might end up | |
1304 | * calling scheduler related locks and ctx->lock nests inside those. | |
1305 | */ | |
1306 | static __must_check struct perf_event_context * | |
1307 | unclone_ctx(struct perf_event_context *ctx) | |
71a851b4 | 1308 | { |
211de6eb PZ |
1309 | struct perf_event_context *parent_ctx = ctx->parent_ctx; |
1310 | ||
1311 | lockdep_assert_held(&ctx->lock); | |
1312 | ||
1313 | if (parent_ctx) | |
71a851b4 | 1314 | ctx->parent_ctx = NULL; |
5a3126d4 | 1315 | ctx->generation++; |
211de6eb PZ |
1316 | |
1317 | return parent_ctx; | |
71a851b4 PZ |
1318 | } |
1319 | ||
1d953111 ON |
1320 | static u32 perf_event_pid_type(struct perf_event *event, struct task_struct *p, |
1321 | enum pid_type type) | |
6844c09d | 1322 | { |
1d953111 | 1323 | u32 nr; |
6844c09d ACM |
1324 | /* |
1325 | * only top level events have the pid namespace they were created in | |
1326 | */ | |
1327 | if (event->parent) | |
1328 | event = event->parent; | |
1329 | ||
1d953111 ON |
1330 | nr = __task_pid_nr_ns(p, type, event->ns); |
1331 | /* avoid -1 if it is idle thread or runs in another ns */ | |
1332 | if (!nr && !pid_alive(p)) | |
1333 | nr = -1; | |
1334 | return nr; | |
6844c09d ACM |
1335 | } |
1336 | ||
1d953111 | 1337 | static u32 perf_event_pid(struct perf_event *event, struct task_struct *p) |
6844c09d | 1338 | { |
6883f81a | 1339 | return perf_event_pid_type(event, p, PIDTYPE_TGID); |
1d953111 | 1340 | } |
6844c09d | 1341 | |
1d953111 ON |
1342 | static u32 perf_event_tid(struct perf_event *event, struct task_struct *p) |
1343 | { | |
1344 | return perf_event_pid_type(event, p, PIDTYPE_PID); | |
6844c09d ACM |
1345 | } |
1346 | ||
7f453c24 | 1347 | /* |
cdd6c482 | 1348 | * If we inherit events we want to return the parent event id |
7f453c24 PZ |
1349 | * to userspace. |
1350 | */ | |
cdd6c482 | 1351 | static u64 primary_event_id(struct perf_event *event) |
7f453c24 | 1352 | { |
cdd6c482 | 1353 | u64 id = event->id; |
7f453c24 | 1354 | |
cdd6c482 IM |
1355 | if (event->parent) |
1356 | id = event->parent->id; | |
7f453c24 PZ |
1357 | |
1358 | return id; | |
1359 | } | |
1360 | ||
25346b93 | 1361 | /* |
cdd6c482 | 1362 | * Get the perf_event_context for a task and lock it. |
63b6da39 | 1363 | * |
25346b93 PM |
1364 | * This has to cope with with the fact that until it is locked, |
1365 | * the context could get moved to another task. | |
1366 | */ | |
cdd6c482 | 1367 | static struct perf_event_context * |
8dc85d54 | 1368 | perf_lock_task_context(struct task_struct *task, int ctxn, unsigned long *flags) |
25346b93 | 1369 | { |
cdd6c482 | 1370 | struct perf_event_context *ctx; |
25346b93 | 1371 | |
9ed6060d | 1372 | retry: |
058ebd0e PZ |
1373 | /* |
1374 | * One of the few rules of preemptible RCU is that one cannot do | |
1375 | * rcu_read_unlock() while holding a scheduler (or nested) lock when | |
2fd59077 | 1376 | * part of the read side critical section was irqs-enabled -- see |
058ebd0e PZ |
1377 | * rcu_read_unlock_special(). |
1378 | * | |
1379 | * Since ctx->lock nests under rq->lock we must ensure the entire read | |
2fd59077 | 1380 | * side critical section has interrupts disabled. |
058ebd0e | 1381 | */ |
2fd59077 | 1382 | local_irq_save(*flags); |
058ebd0e | 1383 | rcu_read_lock(); |
8dc85d54 | 1384 | ctx = rcu_dereference(task->perf_event_ctxp[ctxn]); |
25346b93 PM |
1385 | if (ctx) { |
1386 | /* | |
1387 | * If this context is a clone of another, it might | |
1388 | * get swapped for another underneath us by | |
cdd6c482 | 1389 | * perf_event_task_sched_out, though the |
25346b93 PM |
1390 | * rcu_read_lock() protects us from any context |
1391 | * getting freed. Lock the context and check if it | |
1392 | * got swapped before we could get the lock, and retry | |
1393 | * if so. If we locked the right context, then it | |
1394 | * can't get swapped on us any more. | |
1395 | */ | |
2fd59077 | 1396 | raw_spin_lock(&ctx->lock); |
8dc85d54 | 1397 | if (ctx != rcu_dereference(task->perf_event_ctxp[ctxn])) { |
2fd59077 | 1398 | raw_spin_unlock(&ctx->lock); |
058ebd0e | 1399 | rcu_read_unlock(); |
2fd59077 | 1400 | local_irq_restore(*flags); |
25346b93 PM |
1401 | goto retry; |
1402 | } | |
b49a9e7e | 1403 | |
63b6da39 | 1404 | if (ctx->task == TASK_TOMBSTONE || |
8c94abbb | 1405 | !refcount_inc_not_zero(&ctx->refcount)) { |
2fd59077 | 1406 | raw_spin_unlock(&ctx->lock); |
b49a9e7e | 1407 | ctx = NULL; |
828b6f0e PZ |
1408 | } else { |
1409 | WARN_ON_ONCE(ctx->task != task); | |
b49a9e7e | 1410 | } |
25346b93 PM |
1411 | } |
1412 | rcu_read_unlock(); | |
2fd59077 PM |
1413 | if (!ctx) |
1414 | local_irq_restore(*flags); | |
25346b93 PM |
1415 | return ctx; |
1416 | } | |
1417 | ||
1418 | /* | |
1419 | * Get the context for a task and increment its pin_count so it | |
1420 | * can't get swapped to another task. This also increments its | |
1421 | * reference count so that the context can't get freed. | |
1422 | */ | |
8dc85d54 PZ |
1423 | static struct perf_event_context * |
1424 | perf_pin_task_context(struct task_struct *task, int ctxn) | |
25346b93 | 1425 | { |
cdd6c482 | 1426 | struct perf_event_context *ctx; |
25346b93 PM |
1427 | unsigned long flags; |
1428 | ||
8dc85d54 | 1429 | ctx = perf_lock_task_context(task, ctxn, &flags); |
25346b93 PM |
1430 | if (ctx) { |
1431 | ++ctx->pin_count; | |
e625cce1 | 1432 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1433 | } |
1434 | return ctx; | |
1435 | } | |
1436 | ||
cdd6c482 | 1437 | static void perf_unpin_context(struct perf_event_context *ctx) |
25346b93 PM |
1438 | { |
1439 | unsigned long flags; | |
1440 | ||
e625cce1 | 1441 | raw_spin_lock_irqsave(&ctx->lock, flags); |
25346b93 | 1442 | --ctx->pin_count; |
e625cce1 | 1443 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1444 | } |
1445 | ||
f67218c3 PZ |
1446 | /* |
1447 | * Update the record of the current time in a context. | |
1448 | */ | |
1449 | static void update_context_time(struct perf_event_context *ctx) | |
1450 | { | |
1451 | u64 now = perf_clock(); | |
1452 | ||
1453 | ctx->time += now - ctx->timestamp; | |
1454 | ctx->timestamp = now; | |
1455 | } | |
1456 | ||
4158755d SE |
1457 | static u64 perf_event_time(struct perf_event *event) |
1458 | { | |
1459 | struct perf_event_context *ctx = event->ctx; | |
e5d1367f SE |
1460 | |
1461 | if (is_cgroup_event(event)) | |
1462 | return perf_cgroup_event_time(event); | |
1463 | ||
4158755d SE |
1464 | return ctx ? ctx->time : 0; |
1465 | } | |
1466 | ||
487f05e1 AS |
1467 | static enum event_type_t get_event_type(struct perf_event *event) |
1468 | { | |
1469 | struct perf_event_context *ctx = event->ctx; | |
1470 | enum event_type_t event_type; | |
1471 | ||
1472 | lockdep_assert_held(&ctx->lock); | |
1473 | ||
3bda69c1 AS |
1474 | /* |
1475 | * It's 'group type', really, because if our group leader is | |
1476 | * pinned, so are we. | |
1477 | */ | |
1478 | if (event->group_leader != event) | |
1479 | event = event->group_leader; | |
1480 | ||
487f05e1 AS |
1481 | event_type = event->attr.pinned ? EVENT_PINNED : EVENT_FLEXIBLE; |
1482 | if (!ctx->task) | |
1483 | event_type |= EVENT_CPU; | |
1484 | ||
1485 | return event_type; | |
1486 | } | |
1487 | ||
8e1a2031 | 1488 | /* |
161c85fa | 1489 | * Helper function to initialize event group nodes. |
8e1a2031 | 1490 | */ |
161c85fa | 1491 | static void init_event_group(struct perf_event *event) |
8e1a2031 AB |
1492 | { |
1493 | RB_CLEAR_NODE(&event->group_node); | |
1494 | event->group_index = 0; | |
1495 | } | |
1496 | ||
1497 | /* | |
1498 | * Extract pinned or flexible groups from the context | |
161c85fa | 1499 | * based on event attrs bits. |
8e1a2031 AB |
1500 | */ |
1501 | static struct perf_event_groups * | |
1502 | get_event_groups(struct perf_event *event, struct perf_event_context *ctx) | |
889ff015 FW |
1503 | { |
1504 | if (event->attr.pinned) | |
1505 | return &ctx->pinned_groups; | |
1506 | else | |
1507 | return &ctx->flexible_groups; | |
1508 | } | |
1509 | ||
8e1a2031 | 1510 | /* |
161c85fa | 1511 | * Helper function to initializes perf_event_group trees. |
8e1a2031 | 1512 | */ |
161c85fa | 1513 | static void perf_event_groups_init(struct perf_event_groups *groups) |
8e1a2031 AB |
1514 | { |
1515 | groups->tree = RB_ROOT; | |
1516 | groups->index = 0; | |
1517 | } | |
1518 | ||
1519 | /* | |
1520 | * Compare function for event groups; | |
161c85fa PZ |
1521 | * |
1522 | * Implements complex key that first sorts by CPU and then by virtual index | |
1523 | * which provides ordering when rotating groups for the same CPU. | |
8e1a2031 | 1524 | */ |
161c85fa PZ |
1525 | static bool |
1526 | perf_event_groups_less(struct perf_event *left, struct perf_event *right) | |
8e1a2031 | 1527 | { |
161c85fa PZ |
1528 | if (left->cpu < right->cpu) |
1529 | return true; | |
1530 | if (left->cpu > right->cpu) | |
1531 | return false; | |
1532 | ||
1533 | if (left->group_index < right->group_index) | |
1534 | return true; | |
1535 | if (left->group_index > right->group_index) | |
1536 | return false; | |
1537 | ||
1538 | return false; | |
8e1a2031 AB |
1539 | } |
1540 | ||
1541 | /* | |
161c85fa PZ |
1542 | * Insert @event into @groups' tree; using {@event->cpu, ++@groups->index} for |
1543 | * key (see perf_event_groups_less). This places it last inside the CPU | |
1544 | * subtree. | |
8e1a2031 AB |
1545 | */ |
1546 | static void | |
1547 | perf_event_groups_insert(struct perf_event_groups *groups, | |
161c85fa | 1548 | struct perf_event *event) |
8e1a2031 AB |
1549 | { |
1550 | struct perf_event *node_event; | |
1551 | struct rb_node *parent; | |
1552 | struct rb_node **node; | |
1553 | ||
1554 | event->group_index = ++groups->index; | |
1555 | ||
1556 | node = &groups->tree.rb_node; | |
1557 | parent = *node; | |
1558 | ||
1559 | while (*node) { | |
1560 | parent = *node; | |
161c85fa | 1561 | node_event = container_of(*node, struct perf_event, group_node); |
8e1a2031 AB |
1562 | |
1563 | if (perf_event_groups_less(event, node_event)) | |
1564 | node = &parent->rb_left; | |
1565 | else | |
1566 | node = &parent->rb_right; | |
1567 | } | |
1568 | ||
1569 | rb_link_node(&event->group_node, parent, node); | |
1570 | rb_insert_color(&event->group_node, &groups->tree); | |
1571 | } | |
1572 | ||
1573 | /* | |
161c85fa | 1574 | * Helper function to insert event into the pinned or flexible groups. |
8e1a2031 AB |
1575 | */ |
1576 | static void | |
1577 | add_event_to_groups(struct perf_event *event, struct perf_event_context *ctx) | |
1578 | { | |
1579 | struct perf_event_groups *groups; | |
1580 | ||
1581 | groups = get_event_groups(event, ctx); | |
1582 | perf_event_groups_insert(groups, event); | |
1583 | } | |
1584 | ||
1585 | /* | |
161c85fa | 1586 | * Delete a group from a tree. |
8e1a2031 AB |
1587 | */ |
1588 | static void | |
1589 | perf_event_groups_delete(struct perf_event_groups *groups, | |
161c85fa | 1590 | struct perf_event *event) |
8e1a2031 | 1591 | { |
161c85fa PZ |
1592 | WARN_ON_ONCE(RB_EMPTY_NODE(&event->group_node) || |
1593 | RB_EMPTY_ROOT(&groups->tree)); | |
8e1a2031 | 1594 | |
161c85fa | 1595 | rb_erase(&event->group_node, &groups->tree); |
8e1a2031 AB |
1596 | init_event_group(event); |
1597 | } | |
1598 | ||
1599 | /* | |
161c85fa | 1600 | * Helper function to delete event from its groups. |
8e1a2031 AB |
1601 | */ |
1602 | static void | |
1603 | del_event_from_groups(struct perf_event *event, struct perf_event_context *ctx) | |
1604 | { | |
1605 | struct perf_event_groups *groups; | |
1606 | ||
1607 | groups = get_event_groups(event, ctx); | |
1608 | perf_event_groups_delete(groups, event); | |
1609 | } | |
1610 | ||
1611 | /* | |
161c85fa | 1612 | * Get the leftmost event in the @cpu subtree. |
8e1a2031 AB |
1613 | */ |
1614 | static struct perf_event * | |
1615 | perf_event_groups_first(struct perf_event_groups *groups, int cpu) | |
1616 | { | |
1617 | struct perf_event *node_event = NULL, *match = NULL; | |
1618 | struct rb_node *node = groups->tree.rb_node; | |
1619 | ||
1620 | while (node) { | |
161c85fa | 1621 | node_event = container_of(node, struct perf_event, group_node); |
8e1a2031 AB |
1622 | |
1623 | if (cpu < node_event->cpu) { | |
1624 | node = node->rb_left; | |
1625 | } else if (cpu > node_event->cpu) { | |
1626 | node = node->rb_right; | |
1627 | } else { | |
1628 | match = node_event; | |
1629 | node = node->rb_left; | |
1630 | } | |
1631 | } | |
1632 | ||
1633 | return match; | |
1634 | } | |
1635 | ||
1cac7b1a PZ |
1636 | /* |
1637 | * Like rb_entry_next_safe() for the @cpu subtree. | |
1638 | */ | |
1639 | static struct perf_event * | |
1640 | perf_event_groups_next(struct perf_event *event) | |
1641 | { | |
1642 | struct perf_event *next; | |
1643 | ||
1644 | next = rb_entry_safe(rb_next(&event->group_node), typeof(*event), group_node); | |
1645 | if (next && next->cpu == event->cpu) | |
1646 | return next; | |
1647 | ||
1648 | return NULL; | |
1649 | } | |
1650 | ||
8e1a2031 | 1651 | /* |
161c85fa | 1652 | * Iterate through the whole groups tree. |
8e1a2031 | 1653 | */ |
6e6804d2 PZ |
1654 | #define perf_event_groups_for_each(event, groups) \ |
1655 | for (event = rb_entry_safe(rb_first(&((groups)->tree)), \ | |
1656 | typeof(*event), group_node); event; \ | |
1657 | event = rb_entry_safe(rb_next(&event->group_node), \ | |
1658 | typeof(*event), group_node)) | |
8e1a2031 | 1659 | |
fccc714b | 1660 | /* |
788faab7 | 1661 | * Add an event from the lists for its context. |
fccc714b PZ |
1662 | * Must be called with ctx->mutex and ctx->lock held. |
1663 | */ | |
04289bb9 | 1664 | static void |
cdd6c482 | 1665 | list_add_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1666 | { |
c994d613 PZ |
1667 | lockdep_assert_held(&ctx->lock); |
1668 | ||
8a49542c PZ |
1669 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); |
1670 | event->attach_state |= PERF_ATTACH_CONTEXT; | |
04289bb9 | 1671 | |
0d3d73aa PZ |
1672 | event->tstamp = perf_event_time(event); |
1673 | ||
04289bb9 | 1674 | /* |
8a49542c PZ |
1675 | * If we're a stand alone event or group leader, we go to the context |
1676 | * list, group events are kept attached to the group so that | |
1677 | * perf_group_detach can, at all times, locate all siblings. | |
04289bb9 | 1678 | */ |
8a49542c | 1679 | if (event->group_leader == event) { |
4ff6a8de | 1680 | event->group_caps = event->event_caps; |
8e1a2031 | 1681 | add_event_to_groups(event, ctx); |
5c148194 | 1682 | } |
592903cd | 1683 | |
db4a8356 | 1684 | list_update_cgroup_event(event, ctx, true); |
e5d1367f | 1685 | |
cdd6c482 IM |
1686 | list_add_rcu(&event->event_entry, &ctx->event_list); |
1687 | ctx->nr_events++; | |
1688 | if (event->attr.inherit_stat) | |
bfbd3381 | 1689 | ctx->nr_stat++; |
5a3126d4 PZ |
1690 | |
1691 | ctx->generation++; | |
04289bb9 IM |
1692 | } |
1693 | ||
0231bb53 JO |
1694 | /* |
1695 | * Initialize event state based on the perf_event_attr::disabled. | |
1696 | */ | |
1697 | static inline void perf_event__state_init(struct perf_event *event) | |
1698 | { | |
1699 | event->state = event->attr.disabled ? PERF_EVENT_STATE_OFF : | |
1700 | PERF_EVENT_STATE_INACTIVE; | |
1701 | } | |
1702 | ||
a723968c | 1703 | static void __perf_event_read_size(struct perf_event *event, int nr_siblings) |
c320c7b7 ACM |
1704 | { |
1705 | int entry = sizeof(u64); /* value */ | |
1706 | int size = 0; | |
1707 | int nr = 1; | |
1708 | ||
1709 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
1710 | size += sizeof(u64); | |
1711 | ||
1712 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
1713 | size += sizeof(u64); | |
1714 | ||
1715 | if (event->attr.read_format & PERF_FORMAT_ID) | |
1716 | entry += sizeof(u64); | |
1717 | ||
1718 | if (event->attr.read_format & PERF_FORMAT_GROUP) { | |
a723968c | 1719 | nr += nr_siblings; |
c320c7b7 ACM |
1720 | size += sizeof(u64); |
1721 | } | |
1722 | ||
1723 | size += entry * nr; | |
1724 | event->read_size = size; | |
1725 | } | |
1726 | ||
a723968c | 1727 | static void __perf_event_header_size(struct perf_event *event, u64 sample_type) |
c320c7b7 ACM |
1728 | { |
1729 | struct perf_sample_data *data; | |
c320c7b7 ACM |
1730 | u16 size = 0; |
1731 | ||
c320c7b7 ACM |
1732 | if (sample_type & PERF_SAMPLE_IP) |
1733 | size += sizeof(data->ip); | |
1734 | ||
6844c09d ACM |
1735 | if (sample_type & PERF_SAMPLE_ADDR) |
1736 | size += sizeof(data->addr); | |
1737 | ||
1738 | if (sample_type & PERF_SAMPLE_PERIOD) | |
1739 | size += sizeof(data->period); | |
1740 | ||
c3feedf2 AK |
1741 | if (sample_type & PERF_SAMPLE_WEIGHT) |
1742 | size += sizeof(data->weight); | |
1743 | ||
6844c09d ACM |
1744 | if (sample_type & PERF_SAMPLE_READ) |
1745 | size += event->read_size; | |
1746 | ||
d6be9ad6 SE |
1747 | if (sample_type & PERF_SAMPLE_DATA_SRC) |
1748 | size += sizeof(data->data_src.val); | |
1749 | ||
fdfbbd07 AK |
1750 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
1751 | size += sizeof(data->txn); | |
1752 | ||
fc7ce9c7 KL |
1753 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) |
1754 | size += sizeof(data->phys_addr); | |
1755 | ||
6844c09d ACM |
1756 | event->header_size = size; |
1757 | } | |
1758 | ||
a723968c PZ |
1759 | /* |
1760 | * Called at perf_event creation and when events are attached/detached from a | |
1761 | * group. | |
1762 | */ | |
1763 | static void perf_event__header_size(struct perf_event *event) | |
1764 | { | |
1765 | __perf_event_read_size(event, | |
1766 | event->group_leader->nr_siblings); | |
1767 | __perf_event_header_size(event, event->attr.sample_type); | |
1768 | } | |
1769 | ||
6844c09d ACM |
1770 | static void perf_event__id_header_size(struct perf_event *event) |
1771 | { | |
1772 | struct perf_sample_data *data; | |
1773 | u64 sample_type = event->attr.sample_type; | |
1774 | u16 size = 0; | |
1775 | ||
c320c7b7 ACM |
1776 | if (sample_type & PERF_SAMPLE_TID) |
1777 | size += sizeof(data->tid_entry); | |
1778 | ||
1779 | if (sample_type & PERF_SAMPLE_TIME) | |
1780 | size += sizeof(data->time); | |
1781 | ||
ff3d527c AH |
1782 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
1783 | size += sizeof(data->id); | |
1784 | ||
c320c7b7 ACM |
1785 | if (sample_type & PERF_SAMPLE_ID) |
1786 | size += sizeof(data->id); | |
1787 | ||
1788 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
1789 | size += sizeof(data->stream_id); | |
1790 | ||
1791 | if (sample_type & PERF_SAMPLE_CPU) | |
1792 | size += sizeof(data->cpu_entry); | |
1793 | ||
6844c09d | 1794 | event->id_header_size = size; |
c320c7b7 ACM |
1795 | } |
1796 | ||
a723968c PZ |
1797 | static bool perf_event_validate_size(struct perf_event *event) |
1798 | { | |
1799 | /* | |
1800 | * The values computed here will be over-written when we actually | |
1801 | * attach the event. | |
1802 | */ | |
1803 | __perf_event_read_size(event, event->group_leader->nr_siblings + 1); | |
1804 | __perf_event_header_size(event, event->attr.sample_type & ~PERF_SAMPLE_READ); | |
1805 | perf_event__id_header_size(event); | |
1806 | ||
1807 | /* | |
1808 | * Sum the lot; should not exceed the 64k limit we have on records. | |
1809 | * Conservative limit to allow for callchains and other variable fields. | |
1810 | */ | |
1811 | if (event->read_size + event->header_size + | |
1812 | event->id_header_size + sizeof(struct perf_event_header) >= 16*1024) | |
1813 | return false; | |
1814 | ||
1815 | return true; | |
1816 | } | |
1817 | ||
8a49542c PZ |
1818 | static void perf_group_attach(struct perf_event *event) |
1819 | { | |
c320c7b7 | 1820 | struct perf_event *group_leader = event->group_leader, *pos; |
8a49542c | 1821 | |
a76a82a3 PZ |
1822 | lockdep_assert_held(&event->ctx->lock); |
1823 | ||
74c3337c PZ |
1824 | /* |
1825 | * We can have double attach due to group movement in perf_event_open. | |
1826 | */ | |
1827 | if (event->attach_state & PERF_ATTACH_GROUP) | |
1828 | return; | |
1829 | ||
8a49542c PZ |
1830 | event->attach_state |= PERF_ATTACH_GROUP; |
1831 | ||
1832 | if (group_leader == event) | |
1833 | return; | |
1834 | ||
652884fe PZ |
1835 | WARN_ON_ONCE(group_leader->ctx != event->ctx); |
1836 | ||
4ff6a8de | 1837 | group_leader->group_caps &= event->event_caps; |
8a49542c | 1838 | |
8343aae6 | 1839 | list_add_tail(&event->sibling_list, &group_leader->sibling_list); |
8a49542c | 1840 | group_leader->nr_siblings++; |
c320c7b7 ACM |
1841 | |
1842 | perf_event__header_size(group_leader); | |
1843 | ||
edb39592 | 1844 | for_each_sibling_event(pos, group_leader) |
c320c7b7 | 1845 | perf_event__header_size(pos); |
8a49542c PZ |
1846 | } |
1847 | ||
a63eaf34 | 1848 | /* |
788faab7 | 1849 | * Remove an event from the lists for its context. |
fccc714b | 1850 | * Must be called with ctx->mutex and ctx->lock held. |
a63eaf34 | 1851 | */ |
04289bb9 | 1852 | static void |
cdd6c482 | 1853 | list_del_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1854 | { |
652884fe PZ |
1855 | WARN_ON_ONCE(event->ctx != ctx); |
1856 | lockdep_assert_held(&ctx->lock); | |
1857 | ||
8a49542c PZ |
1858 | /* |
1859 | * We can have double detach due to exit/hot-unplug + close. | |
1860 | */ | |
1861 | if (!(event->attach_state & PERF_ATTACH_CONTEXT)) | |
a63eaf34 | 1862 | return; |
8a49542c PZ |
1863 | |
1864 | event->attach_state &= ~PERF_ATTACH_CONTEXT; | |
1865 | ||
db4a8356 | 1866 | list_update_cgroup_event(event, ctx, false); |
e5d1367f | 1867 | |
cdd6c482 IM |
1868 | ctx->nr_events--; |
1869 | if (event->attr.inherit_stat) | |
bfbd3381 | 1870 | ctx->nr_stat--; |
8bc20959 | 1871 | |
cdd6c482 | 1872 | list_del_rcu(&event->event_entry); |
04289bb9 | 1873 | |
8a49542c | 1874 | if (event->group_leader == event) |
8e1a2031 | 1875 | del_event_from_groups(event, ctx); |
5c148194 | 1876 | |
b2e74a26 SE |
1877 | /* |
1878 | * If event was in error state, then keep it | |
1879 | * that way, otherwise bogus counts will be | |
1880 | * returned on read(). The only way to get out | |
1881 | * of error state is by explicit re-enabling | |
1882 | * of the event | |
1883 | */ | |
1884 | if (event->state > PERF_EVENT_STATE_OFF) | |
0d3d73aa | 1885 | perf_event_set_state(event, PERF_EVENT_STATE_OFF); |
5a3126d4 PZ |
1886 | |
1887 | ctx->generation++; | |
050735b0 PZ |
1888 | } |
1889 | ||
ab43762e AS |
1890 | static int |
1891 | perf_aux_output_match(struct perf_event *event, struct perf_event *aux_event) | |
1892 | { | |
1893 | if (!has_aux(aux_event)) | |
1894 | return 0; | |
1895 | ||
1896 | if (!event->pmu->aux_output_match) | |
1897 | return 0; | |
1898 | ||
1899 | return event->pmu->aux_output_match(aux_event); | |
1900 | } | |
1901 | ||
1902 | static void put_event(struct perf_event *event); | |
1903 | static void event_sched_out(struct perf_event *event, | |
1904 | struct perf_cpu_context *cpuctx, | |
1905 | struct perf_event_context *ctx); | |
1906 | ||
1907 | static void perf_put_aux_event(struct perf_event *event) | |
1908 | { | |
1909 | struct perf_event_context *ctx = event->ctx; | |
1910 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
1911 | struct perf_event *iter; | |
1912 | ||
1913 | /* | |
1914 | * If event uses aux_event tear down the link | |
1915 | */ | |
1916 | if (event->aux_event) { | |
1917 | iter = event->aux_event; | |
1918 | event->aux_event = NULL; | |
1919 | put_event(iter); | |
1920 | return; | |
1921 | } | |
1922 | ||
1923 | /* | |
1924 | * If the event is an aux_event, tear down all links to | |
1925 | * it from other events. | |
1926 | */ | |
1927 | for_each_sibling_event(iter, event->group_leader) { | |
1928 | if (iter->aux_event != event) | |
1929 | continue; | |
1930 | ||
1931 | iter->aux_event = NULL; | |
1932 | put_event(event); | |
1933 | ||
1934 | /* | |
1935 | * If it's ACTIVE, schedule it out and put it into ERROR | |
1936 | * state so that we don't try to schedule it again. Note | |
1937 | * that perf_event_enable() will clear the ERROR status. | |
1938 | */ | |
1939 | event_sched_out(iter, cpuctx, ctx); | |
1940 | perf_event_set_state(event, PERF_EVENT_STATE_ERROR); | |
1941 | } | |
1942 | } | |
1943 | ||
1944 | static int perf_get_aux_event(struct perf_event *event, | |
1945 | struct perf_event *group_leader) | |
1946 | { | |
1947 | /* | |
1948 | * Our group leader must be an aux event if we want to be | |
1949 | * an aux_output. This way, the aux event will precede its | |
1950 | * aux_output events in the group, and therefore will always | |
1951 | * schedule first. | |
1952 | */ | |
1953 | if (!group_leader) | |
1954 | return 0; | |
1955 | ||
1956 | if (!perf_aux_output_match(event, group_leader)) | |
1957 | return 0; | |
1958 | ||
1959 | if (!atomic_long_inc_not_zero(&group_leader->refcount)) | |
1960 | return 0; | |
1961 | ||
1962 | /* | |
1963 | * Link aux_outputs to their aux event; this is undone in | |
1964 | * perf_group_detach() by perf_put_aux_event(). When the | |
1965 | * group in torn down, the aux_output events loose their | |
1966 | * link to the aux_event and can't schedule any more. | |
1967 | */ | |
1968 | event->aux_event = group_leader; | |
1969 | ||
1970 | return 1; | |
1971 | } | |
1972 | ||
8a49542c | 1973 | static void perf_group_detach(struct perf_event *event) |
050735b0 PZ |
1974 | { |
1975 | struct perf_event *sibling, *tmp; | |
6668128a | 1976 | struct perf_event_context *ctx = event->ctx; |
8a49542c | 1977 | |
6668128a | 1978 | lockdep_assert_held(&ctx->lock); |
a76a82a3 | 1979 | |
8a49542c PZ |
1980 | /* |
1981 | * We can have double detach due to exit/hot-unplug + close. | |
1982 | */ | |
1983 | if (!(event->attach_state & PERF_ATTACH_GROUP)) | |
1984 | return; | |
1985 | ||
1986 | event->attach_state &= ~PERF_ATTACH_GROUP; | |
1987 | ||
ab43762e AS |
1988 | perf_put_aux_event(event); |
1989 | ||
8a49542c PZ |
1990 | /* |
1991 | * If this is a sibling, remove it from its group. | |
1992 | */ | |
1993 | if (event->group_leader != event) { | |
8343aae6 | 1994 | list_del_init(&event->sibling_list); |
8a49542c | 1995 | event->group_leader->nr_siblings--; |
c320c7b7 | 1996 | goto out; |
8a49542c PZ |
1997 | } |
1998 | ||
04289bb9 | 1999 | /* |
cdd6c482 IM |
2000 | * If this was a group event with sibling events then |
2001 | * upgrade the siblings to singleton events by adding them | |
8a49542c | 2002 | * to whatever list we are on. |
04289bb9 | 2003 | */ |
8343aae6 | 2004 | list_for_each_entry_safe(sibling, tmp, &event->sibling_list, sibling_list) { |
8e1a2031 | 2005 | |
04289bb9 | 2006 | sibling->group_leader = sibling; |
24868367 | 2007 | list_del_init(&sibling->sibling_list); |
d6f962b5 FW |
2008 | |
2009 | /* Inherit group flags from the previous leader */ | |
4ff6a8de | 2010 | sibling->group_caps = event->group_caps; |
652884fe | 2011 | |
8e1a2031 | 2012 | if (!RB_EMPTY_NODE(&event->group_node)) { |
8e1a2031 | 2013 | add_event_to_groups(sibling, event->ctx); |
6668128a PZ |
2014 | |
2015 | if (sibling->state == PERF_EVENT_STATE_ACTIVE) { | |
2016 | struct list_head *list = sibling->attr.pinned ? | |
2017 | &ctx->pinned_active : &ctx->flexible_active; | |
2018 | ||
2019 | list_add_tail(&sibling->active_list, list); | |
2020 | } | |
8e1a2031 AB |
2021 | } |
2022 | ||
652884fe | 2023 | WARN_ON_ONCE(sibling->ctx != event->ctx); |
04289bb9 | 2024 | } |
c320c7b7 ACM |
2025 | |
2026 | out: | |
2027 | perf_event__header_size(event->group_leader); | |
2028 | ||
edb39592 | 2029 | for_each_sibling_event(tmp, event->group_leader) |
c320c7b7 | 2030 | perf_event__header_size(tmp); |
04289bb9 IM |
2031 | } |
2032 | ||
fadfe7be JO |
2033 | static bool is_orphaned_event(struct perf_event *event) |
2034 | { | |
a69b0ca4 | 2035 | return event->state == PERF_EVENT_STATE_DEAD; |
fadfe7be JO |
2036 | } |
2037 | ||
2c81a647 | 2038 | static inline int __pmu_filter_match(struct perf_event *event) |
66eb579e MR |
2039 | { |
2040 | struct pmu *pmu = event->pmu; | |
2041 | return pmu->filter_match ? pmu->filter_match(event) : 1; | |
2042 | } | |
2043 | ||
2c81a647 MR |
2044 | /* |
2045 | * Check whether we should attempt to schedule an event group based on | |
2046 | * PMU-specific filtering. An event group can consist of HW and SW events, | |
2047 | * potentially with a SW leader, so we must check all the filters, to | |
2048 | * determine whether a group is schedulable: | |
2049 | */ | |
2050 | static inline int pmu_filter_match(struct perf_event *event) | |
2051 | { | |
edb39592 | 2052 | struct perf_event *sibling; |
2c81a647 MR |
2053 | |
2054 | if (!__pmu_filter_match(event)) | |
2055 | return 0; | |
2056 | ||
edb39592 PZ |
2057 | for_each_sibling_event(sibling, event) { |
2058 | if (!__pmu_filter_match(sibling)) | |
2c81a647 MR |
2059 | return 0; |
2060 | } | |
2061 | ||
2062 | return 1; | |
2063 | } | |
2064 | ||
fa66f07a SE |
2065 | static inline int |
2066 | event_filter_match(struct perf_event *event) | |
2067 | { | |
0b8f1e2e PZ |
2068 | return (event->cpu == -1 || event->cpu == smp_processor_id()) && |
2069 | perf_cgroup_match(event) && pmu_filter_match(event); | |
fa66f07a SE |
2070 | } |
2071 | ||
9ffcfa6f SE |
2072 | static void |
2073 | event_sched_out(struct perf_event *event, | |
3b6f9e5c | 2074 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 2075 | struct perf_event_context *ctx) |
3b6f9e5c | 2076 | { |
0d3d73aa | 2077 | enum perf_event_state state = PERF_EVENT_STATE_INACTIVE; |
652884fe PZ |
2078 | |
2079 | WARN_ON_ONCE(event->ctx != ctx); | |
2080 | lockdep_assert_held(&ctx->lock); | |
2081 | ||
cdd6c482 | 2082 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
9ffcfa6f | 2083 | return; |
3b6f9e5c | 2084 | |
6668128a PZ |
2085 | /* |
2086 | * Asymmetry; we only schedule events _IN_ through ctx_sched_in(), but | |
2087 | * we can schedule events _OUT_ individually through things like | |
2088 | * __perf_remove_from_context(). | |
2089 | */ | |
2090 | list_del_init(&event->active_list); | |
2091 | ||
44377277 AS |
2092 | perf_pmu_disable(event->pmu); |
2093 | ||
28a967c3 PZ |
2094 | event->pmu->del(event, 0); |
2095 | event->oncpu = -1; | |
0d3d73aa | 2096 | |
1d54ad94 PZ |
2097 | if (READ_ONCE(event->pending_disable) >= 0) { |
2098 | WRITE_ONCE(event->pending_disable, -1); | |
0d3d73aa | 2099 | state = PERF_EVENT_STATE_OFF; |
970892a9 | 2100 | } |
0d3d73aa | 2101 | perf_event_set_state(event, state); |
3b6f9e5c | 2102 | |
cdd6c482 | 2103 | if (!is_software_event(event)) |
3b6f9e5c | 2104 | cpuctx->active_oncpu--; |
2fde4f94 MR |
2105 | if (!--ctx->nr_active) |
2106 | perf_event_ctx_deactivate(ctx); | |
0f5a2601 PZ |
2107 | if (event->attr.freq && event->attr.sample_freq) |
2108 | ctx->nr_freq--; | |
cdd6c482 | 2109 | if (event->attr.exclusive || !cpuctx->active_oncpu) |
3b6f9e5c | 2110 | cpuctx->exclusive = 0; |
44377277 AS |
2111 | |
2112 | perf_pmu_enable(event->pmu); | |
3b6f9e5c PM |
2113 | } |
2114 | ||
d859e29f | 2115 | static void |
cdd6c482 | 2116 | group_sched_out(struct perf_event *group_event, |
d859e29f | 2117 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 2118 | struct perf_event_context *ctx) |
d859e29f | 2119 | { |
cdd6c482 | 2120 | struct perf_event *event; |
0d3d73aa PZ |
2121 | |
2122 | if (group_event->state != PERF_EVENT_STATE_ACTIVE) | |
2123 | return; | |
d859e29f | 2124 | |
3f005e7d MR |
2125 | perf_pmu_disable(ctx->pmu); |
2126 | ||
cdd6c482 | 2127 | event_sched_out(group_event, cpuctx, ctx); |
d859e29f PM |
2128 | |
2129 | /* | |
2130 | * Schedule out siblings (if any): | |
2131 | */ | |
edb39592 | 2132 | for_each_sibling_event(event, group_event) |
cdd6c482 | 2133 | event_sched_out(event, cpuctx, ctx); |
d859e29f | 2134 | |
3f005e7d MR |
2135 | perf_pmu_enable(ctx->pmu); |
2136 | ||
0d3d73aa | 2137 | if (group_event->attr.exclusive) |
d859e29f PM |
2138 | cpuctx->exclusive = 0; |
2139 | } | |
2140 | ||
45a0e07a | 2141 | #define DETACH_GROUP 0x01UL |
0017960f | 2142 | |
0793a61d | 2143 | /* |
cdd6c482 | 2144 | * Cross CPU call to remove a performance event |
0793a61d | 2145 | * |
cdd6c482 | 2146 | * We disable the event on the hardware level first. After that we |
0793a61d TG |
2147 | * remove it from the context list. |
2148 | */ | |
fae3fde6 PZ |
2149 | static void |
2150 | __perf_remove_from_context(struct perf_event *event, | |
2151 | struct perf_cpu_context *cpuctx, | |
2152 | struct perf_event_context *ctx, | |
2153 | void *info) | |
0793a61d | 2154 | { |
45a0e07a | 2155 | unsigned long flags = (unsigned long)info; |
0793a61d | 2156 | |
3c5c8711 PZ |
2157 | if (ctx->is_active & EVENT_TIME) { |
2158 | update_context_time(ctx); | |
2159 | update_cgrp_time_from_cpuctx(cpuctx); | |
2160 | } | |
2161 | ||
cdd6c482 | 2162 | event_sched_out(event, cpuctx, ctx); |
45a0e07a | 2163 | if (flags & DETACH_GROUP) |
46ce0fe9 | 2164 | perf_group_detach(event); |
cdd6c482 | 2165 | list_del_event(event, ctx); |
39a43640 PZ |
2166 | |
2167 | if (!ctx->nr_events && ctx->is_active) { | |
64ce3126 | 2168 | ctx->is_active = 0; |
39a43640 PZ |
2169 | if (ctx->task) { |
2170 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
2171 | cpuctx->task_ctx = NULL; | |
2172 | } | |
64ce3126 | 2173 | } |
0793a61d TG |
2174 | } |
2175 | ||
0793a61d | 2176 | /* |
cdd6c482 | 2177 | * Remove the event from a task's (or a CPU's) list of events. |
0793a61d | 2178 | * |
cdd6c482 IM |
2179 | * If event->ctx is a cloned context, callers must make sure that |
2180 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 PM |
2181 | * remains valid. This is OK when called from perf_release since |
2182 | * that only calls us on the top-level context, which can't be a clone. | |
cdd6c482 | 2183 | * When called from perf_event_exit_task, it's OK because the |
c93f7669 | 2184 | * context has been detached from its task. |
0793a61d | 2185 | */ |
45a0e07a | 2186 | static void perf_remove_from_context(struct perf_event *event, unsigned long flags) |
0793a61d | 2187 | { |
a76a82a3 PZ |
2188 | struct perf_event_context *ctx = event->ctx; |
2189 | ||
2190 | lockdep_assert_held(&ctx->mutex); | |
0793a61d | 2191 | |
45a0e07a | 2192 | event_function_call(event, __perf_remove_from_context, (void *)flags); |
a76a82a3 PZ |
2193 | |
2194 | /* | |
2195 | * The above event_function_call() can NO-OP when it hits | |
2196 | * TASK_TOMBSTONE. In that case we must already have been detached | |
2197 | * from the context (by perf_event_exit_event()) but the grouping | |
2198 | * might still be in-tact. | |
2199 | */ | |
2200 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); | |
2201 | if ((flags & DETACH_GROUP) && | |
2202 | (event->attach_state & PERF_ATTACH_GROUP)) { | |
2203 | /* | |
2204 | * Since in that case we cannot possibly be scheduled, simply | |
2205 | * detach now. | |
2206 | */ | |
2207 | raw_spin_lock_irq(&ctx->lock); | |
2208 | perf_group_detach(event); | |
2209 | raw_spin_unlock_irq(&ctx->lock); | |
2210 | } | |
0793a61d TG |
2211 | } |
2212 | ||
d859e29f | 2213 | /* |
cdd6c482 | 2214 | * Cross CPU call to disable a performance event |
d859e29f | 2215 | */ |
fae3fde6 PZ |
2216 | static void __perf_event_disable(struct perf_event *event, |
2217 | struct perf_cpu_context *cpuctx, | |
2218 | struct perf_event_context *ctx, | |
2219 | void *info) | |
7b648018 | 2220 | { |
fae3fde6 PZ |
2221 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
2222 | return; | |
7b648018 | 2223 | |
3c5c8711 PZ |
2224 | if (ctx->is_active & EVENT_TIME) { |
2225 | update_context_time(ctx); | |
2226 | update_cgrp_time_from_event(event); | |
2227 | } | |
2228 | ||
fae3fde6 PZ |
2229 | if (event == event->group_leader) |
2230 | group_sched_out(event, cpuctx, ctx); | |
2231 | else | |
2232 | event_sched_out(event, cpuctx, ctx); | |
0d3d73aa PZ |
2233 | |
2234 | perf_event_set_state(event, PERF_EVENT_STATE_OFF); | |
7b648018 PZ |
2235 | } |
2236 | ||
d859e29f | 2237 | /* |
788faab7 | 2238 | * Disable an event. |
c93f7669 | 2239 | * |
cdd6c482 IM |
2240 | * If event->ctx is a cloned context, callers must make sure that |
2241 | * every task struct that event->ctx->task could possibly point to | |
9f014e3a | 2242 | * remains valid. This condition is satisfied when called through |
cdd6c482 IM |
2243 | * perf_event_for_each_child or perf_event_for_each because they |
2244 | * hold the top-level event's child_mutex, so any descendant that | |
8ba289b8 PZ |
2245 | * goes to exit will block in perf_event_exit_event(). |
2246 | * | |
cdd6c482 | 2247 | * When called from perf_pending_event it's OK because event->ctx |
c93f7669 | 2248 | * is the current context on this CPU and preemption is disabled, |
cdd6c482 | 2249 | * hence we can't get into perf_event_task_sched_out for this context. |
d859e29f | 2250 | */ |
f63a8daa | 2251 | static void _perf_event_disable(struct perf_event *event) |
d859e29f | 2252 | { |
cdd6c482 | 2253 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 2254 | |
e625cce1 | 2255 | raw_spin_lock_irq(&ctx->lock); |
7b648018 | 2256 | if (event->state <= PERF_EVENT_STATE_OFF) { |
e625cce1 | 2257 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 2258 | return; |
53cfbf59 | 2259 | } |
e625cce1 | 2260 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 2261 | |
fae3fde6 PZ |
2262 | event_function_call(event, __perf_event_disable, NULL); |
2263 | } | |
2264 | ||
2265 | void perf_event_disable_local(struct perf_event *event) | |
2266 | { | |
2267 | event_function_local(event, __perf_event_disable, NULL); | |
d859e29f | 2268 | } |
f63a8daa PZ |
2269 | |
2270 | /* | |
2271 | * Strictly speaking kernel users cannot create groups and therefore this | |
2272 | * interface does not need the perf_event_ctx_lock() magic. | |
2273 | */ | |
2274 | void perf_event_disable(struct perf_event *event) | |
2275 | { | |
2276 | struct perf_event_context *ctx; | |
2277 | ||
2278 | ctx = perf_event_ctx_lock(event); | |
2279 | _perf_event_disable(event); | |
2280 | perf_event_ctx_unlock(event, ctx); | |
2281 | } | |
dcfce4a0 | 2282 | EXPORT_SYMBOL_GPL(perf_event_disable); |
d859e29f | 2283 | |
5aab90ce JO |
2284 | void perf_event_disable_inatomic(struct perf_event *event) |
2285 | { | |
1d54ad94 PZ |
2286 | WRITE_ONCE(event->pending_disable, smp_processor_id()); |
2287 | /* can fail, see perf_pending_event_disable() */ | |
5aab90ce JO |
2288 | irq_work_queue(&event->pending); |
2289 | } | |
2290 | ||
e5d1367f | 2291 | static void perf_set_shadow_time(struct perf_event *event, |
0d3d73aa | 2292 | struct perf_event_context *ctx) |
e5d1367f SE |
2293 | { |
2294 | /* | |
2295 | * use the correct time source for the time snapshot | |
2296 | * | |
2297 | * We could get by without this by leveraging the | |
2298 | * fact that to get to this function, the caller | |
2299 | * has most likely already called update_context_time() | |
2300 | * and update_cgrp_time_xx() and thus both timestamp | |
2301 | * are identical (or very close). Given that tstamp is, | |
2302 | * already adjusted for cgroup, we could say that: | |
2303 | * tstamp - ctx->timestamp | |
2304 | * is equivalent to | |
2305 | * tstamp - cgrp->timestamp. | |
2306 | * | |
2307 | * Then, in perf_output_read(), the calculation would | |
2308 | * work with no changes because: | |
2309 | * - event is guaranteed scheduled in | |
2310 | * - no scheduled out in between | |
2311 | * - thus the timestamp would be the same | |
2312 | * | |
2313 | * But this is a bit hairy. | |
2314 | * | |
2315 | * So instead, we have an explicit cgroup call to remain | |
2316 | * within the time time source all along. We believe it | |
2317 | * is cleaner and simpler to understand. | |
2318 | */ | |
2319 | if (is_cgroup_event(event)) | |
0d3d73aa | 2320 | perf_cgroup_set_shadow_time(event, event->tstamp); |
e5d1367f | 2321 | else |
0d3d73aa | 2322 | event->shadow_ctx_time = event->tstamp - ctx->timestamp; |
e5d1367f SE |
2323 | } |
2324 | ||
4fe757dd PZ |
2325 | #define MAX_INTERRUPTS (~0ULL) |
2326 | ||
2327 | static void perf_log_throttle(struct perf_event *event, int enable); | |
ec0d7729 | 2328 | static void perf_log_itrace_start(struct perf_event *event); |
4fe757dd | 2329 | |
235c7fc7 | 2330 | static int |
9ffcfa6f | 2331 | event_sched_in(struct perf_event *event, |
235c7fc7 | 2332 | struct perf_cpu_context *cpuctx, |
6e37738a | 2333 | struct perf_event_context *ctx) |
235c7fc7 | 2334 | { |
44377277 | 2335 | int ret = 0; |
4158755d | 2336 | |
63342411 PZ |
2337 | lockdep_assert_held(&ctx->lock); |
2338 | ||
cdd6c482 | 2339 | if (event->state <= PERF_EVENT_STATE_OFF) |
235c7fc7 IM |
2340 | return 0; |
2341 | ||
95ff4ca2 AS |
2342 | WRITE_ONCE(event->oncpu, smp_processor_id()); |
2343 | /* | |
0c1cbc18 PZ |
2344 | * Order event::oncpu write to happen before the ACTIVE state is |
2345 | * visible. This allows perf_event_{stop,read}() to observe the correct | |
2346 | * ->oncpu if it sees ACTIVE. | |
95ff4ca2 AS |
2347 | */ |
2348 | smp_wmb(); | |
0d3d73aa | 2349 | perf_event_set_state(event, PERF_EVENT_STATE_ACTIVE); |
4fe757dd PZ |
2350 | |
2351 | /* | |
2352 | * Unthrottle events, since we scheduled we might have missed several | |
2353 | * ticks already, also for a heavily scheduling task there is little | |
2354 | * guarantee it'll get a tick in a timely manner. | |
2355 | */ | |
2356 | if (unlikely(event->hw.interrupts == MAX_INTERRUPTS)) { | |
2357 | perf_log_throttle(event, 1); | |
2358 | event->hw.interrupts = 0; | |
2359 | } | |
2360 | ||
44377277 AS |
2361 | perf_pmu_disable(event->pmu); |
2362 | ||
0d3d73aa | 2363 | perf_set_shadow_time(event, ctx); |
72f669c0 | 2364 | |
ec0d7729 AS |
2365 | perf_log_itrace_start(event); |
2366 | ||
a4eaf7f1 | 2367 | if (event->pmu->add(event, PERF_EF_START)) { |
0d3d73aa | 2368 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
cdd6c482 | 2369 | event->oncpu = -1; |
44377277 AS |
2370 | ret = -EAGAIN; |
2371 | goto out; | |
235c7fc7 IM |
2372 | } |
2373 | ||
cdd6c482 | 2374 | if (!is_software_event(event)) |
3b6f9e5c | 2375 | cpuctx->active_oncpu++; |
2fde4f94 MR |
2376 | if (!ctx->nr_active++) |
2377 | perf_event_ctx_activate(ctx); | |
0f5a2601 PZ |
2378 | if (event->attr.freq && event->attr.sample_freq) |
2379 | ctx->nr_freq++; | |
235c7fc7 | 2380 | |
cdd6c482 | 2381 | if (event->attr.exclusive) |
3b6f9e5c PM |
2382 | cpuctx->exclusive = 1; |
2383 | ||
44377277 AS |
2384 | out: |
2385 | perf_pmu_enable(event->pmu); | |
2386 | ||
2387 | return ret; | |
235c7fc7 IM |
2388 | } |
2389 | ||
6751b71e | 2390 | static int |
cdd6c482 | 2391 | group_sched_in(struct perf_event *group_event, |
6751b71e | 2392 | struct perf_cpu_context *cpuctx, |
6e37738a | 2393 | struct perf_event_context *ctx) |
6751b71e | 2394 | { |
6bde9b6c | 2395 | struct perf_event *event, *partial_group = NULL; |
4a234593 | 2396 | struct pmu *pmu = ctx->pmu; |
6751b71e | 2397 | |
cdd6c482 | 2398 | if (group_event->state == PERF_EVENT_STATE_OFF) |
6751b71e PM |
2399 | return 0; |
2400 | ||
fbbe0701 | 2401 | pmu->start_txn(pmu, PERF_PMU_TXN_ADD); |
6bde9b6c | 2402 | |
9ffcfa6f | 2403 | if (event_sched_in(group_event, cpuctx, ctx)) { |
ad5133b7 | 2404 | pmu->cancel_txn(pmu); |
272325c4 | 2405 | perf_mux_hrtimer_restart(cpuctx); |
6751b71e | 2406 | return -EAGAIN; |
90151c35 | 2407 | } |
6751b71e PM |
2408 | |
2409 | /* | |
2410 | * Schedule in siblings as one group (if any): | |
2411 | */ | |
edb39592 | 2412 | for_each_sibling_event(event, group_event) { |
9ffcfa6f | 2413 | if (event_sched_in(event, cpuctx, ctx)) { |
cdd6c482 | 2414 | partial_group = event; |
6751b71e PM |
2415 | goto group_error; |
2416 | } | |
2417 | } | |
2418 | ||
9ffcfa6f | 2419 | if (!pmu->commit_txn(pmu)) |
6e85158c | 2420 | return 0; |
9ffcfa6f | 2421 | |
6751b71e PM |
2422 | group_error: |
2423 | /* | |
2424 | * Groups can be scheduled in as one unit only, so undo any | |
2425 | * partial group before returning: | |
0d3d73aa | 2426 | * The events up to the failed event are scheduled out normally. |
6751b71e | 2427 | */ |
edb39592 | 2428 | for_each_sibling_event(event, group_event) { |
cdd6c482 | 2429 | if (event == partial_group) |
0d3d73aa | 2430 | break; |
d7842da4 | 2431 | |
0d3d73aa | 2432 | event_sched_out(event, cpuctx, ctx); |
6751b71e | 2433 | } |
9ffcfa6f | 2434 | event_sched_out(group_event, cpuctx, ctx); |
6751b71e | 2435 | |
ad5133b7 | 2436 | pmu->cancel_txn(pmu); |
90151c35 | 2437 | |
272325c4 | 2438 | perf_mux_hrtimer_restart(cpuctx); |
9e630205 | 2439 | |
6751b71e PM |
2440 | return -EAGAIN; |
2441 | } | |
2442 | ||
3b6f9e5c | 2443 | /* |
cdd6c482 | 2444 | * Work out whether we can put this event group on the CPU now. |
3b6f9e5c | 2445 | */ |
cdd6c482 | 2446 | static int group_can_go_on(struct perf_event *event, |
3b6f9e5c PM |
2447 | struct perf_cpu_context *cpuctx, |
2448 | int can_add_hw) | |
2449 | { | |
2450 | /* | |
cdd6c482 | 2451 | * Groups consisting entirely of software events can always go on. |
3b6f9e5c | 2452 | */ |
4ff6a8de | 2453 | if (event->group_caps & PERF_EV_CAP_SOFTWARE) |
3b6f9e5c PM |
2454 | return 1; |
2455 | /* | |
2456 | * If an exclusive group is already on, no other hardware | |
cdd6c482 | 2457 | * events can go on. |
3b6f9e5c PM |
2458 | */ |
2459 | if (cpuctx->exclusive) | |
2460 | return 0; | |
2461 | /* | |
2462 | * If this group is exclusive and there are already | |
cdd6c482 | 2463 | * events on the CPU, it can't go on. |
3b6f9e5c | 2464 | */ |
cdd6c482 | 2465 | if (event->attr.exclusive && cpuctx->active_oncpu) |
3b6f9e5c PM |
2466 | return 0; |
2467 | /* | |
2468 | * Otherwise, try to add it if all previous groups were able | |
2469 | * to go on. | |
2470 | */ | |
2471 | return can_add_hw; | |
2472 | } | |
2473 | ||
cdd6c482 IM |
2474 | static void add_event_to_ctx(struct perf_event *event, |
2475 | struct perf_event_context *ctx) | |
53cfbf59 | 2476 | { |
cdd6c482 | 2477 | list_add_event(event, ctx); |
8a49542c | 2478 | perf_group_attach(event); |
53cfbf59 PM |
2479 | } |
2480 | ||
bd2afa49 PZ |
2481 | static void ctx_sched_out(struct perf_event_context *ctx, |
2482 | struct perf_cpu_context *cpuctx, | |
2483 | enum event_type_t event_type); | |
2c29ef0f PZ |
2484 | static void |
2485 | ctx_sched_in(struct perf_event_context *ctx, | |
2486 | struct perf_cpu_context *cpuctx, | |
2487 | enum event_type_t event_type, | |
2488 | struct task_struct *task); | |
fe4b04fa | 2489 | |
bd2afa49 | 2490 | static void task_ctx_sched_out(struct perf_cpu_context *cpuctx, |
487f05e1 AS |
2491 | struct perf_event_context *ctx, |
2492 | enum event_type_t event_type) | |
bd2afa49 PZ |
2493 | { |
2494 | if (!cpuctx->task_ctx) | |
2495 | return; | |
2496 | ||
2497 | if (WARN_ON_ONCE(ctx != cpuctx->task_ctx)) | |
2498 | return; | |
2499 | ||
487f05e1 | 2500 | ctx_sched_out(ctx, cpuctx, event_type); |
bd2afa49 PZ |
2501 | } |
2502 | ||
dce5855b PZ |
2503 | static void perf_event_sched_in(struct perf_cpu_context *cpuctx, |
2504 | struct perf_event_context *ctx, | |
2505 | struct task_struct *task) | |
2506 | { | |
2507 | cpu_ctx_sched_in(cpuctx, EVENT_PINNED, task); | |
2508 | if (ctx) | |
2509 | ctx_sched_in(ctx, cpuctx, EVENT_PINNED, task); | |
2510 | cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE, task); | |
2511 | if (ctx) | |
2512 | ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE, task); | |
2513 | } | |
2514 | ||
487f05e1 AS |
2515 | /* |
2516 | * We want to maintain the following priority of scheduling: | |
2517 | * - CPU pinned (EVENT_CPU | EVENT_PINNED) | |
2518 | * - task pinned (EVENT_PINNED) | |
2519 | * - CPU flexible (EVENT_CPU | EVENT_FLEXIBLE) | |
2520 | * - task flexible (EVENT_FLEXIBLE). | |
2521 | * | |
2522 | * In order to avoid unscheduling and scheduling back in everything every | |
2523 | * time an event is added, only do it for the groups of equal priority and | |
2524 | * below. | |
2525 | * | |
2526 | * This can be called after a batch operation on task events, in which case | |
2527 | * event_type is a bit mask of the types of events involved. For CPU events, | |
2528 | * event_type is only either EVENT_PINNED or EVENT_FLEXIBLE. | |
2529 | */ | |
3e349507 | 2530 | static void ctx_resched(struct perf_cpu_context *cpuctx, |
487f05e1 AS |
2531 | struct perf_event_context *task_ctx, |
2532 | enum event_type_t event_type) | |
0017960f | 2533 | { |
bd903afe | 2534 | enum event_type_t ctx_event_type; |
487f05e1 AS |
2535 | bool cpu_event = !!(event_type & EVENT_CPU); |
2536 | ||
2537 | /* | |
2538 | * If pinned groups are involved, flexible groups also need to be | |
2539 | * scheduled out. | |
2540 | */ | |
2541 | if (event_type & EVENT_PINNED) | |
2542 | event_type |= EVENT_FLEXIBLE; | |
2543 | ||
bd903afe SL |
2544 | ctx_event_type = event_type & EVENT_ALL; |
2545 | ||
3e349507 PZ |
2546 | perf_pmu_disable(cpuctx->ctx.pmu); |
2547 | if (task_ctx) | |
487f05e1 AS |
2548 | task_ctx_sched_out(cpuctx, task_ctx, event_type); |
2549 | ||
2550 | /* | |
2551 | * Decide which cpu ctx groups to schedule out based on the types | |
2552 | * of events that caused rescheduling: | |
2553 | * - EVENT_CPU: schedule out corresponding groups; | |
2554 | * - EVENT_PINNED task events: schedule out EVENT_FLEXIBLE groups; | |
2555 | * - otherwise, do nothing more. | |
2556 | */ | |
2557 | if (cpu_event) | |
2558 | cpu_ctx_sched_out(cpuctx, ctx_event_type); | |
2559 | else if (ctx_event_type & EVENT_PINNED) | |
2560 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
2561 | ||
3e349507 PZ |
2562 | perf_event_sched_in(cpuctx, task_ctx, current); |
2563 | perf_pmu_enable(cpuctx->ctx.pmu); | |
0017960f PZ |
2564 | } |
2565 | ||
c68d224e SE |
2566 | void perf_pmu_resched(struct pmu *pmu) |
2567 | { | |
2568 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); | |
2569 | struct perf_event_context *task_ctx = cpuctx->task_ctx; | |
2570 | ||
2571 | perf_ctx_lock(cpuctx, task_ctx); | |
2572 | ctx_resched(cpuctx, task_ctx, EVENT_ALL|EVENT_CPU); | |
2573 | perf_ctx_unlock(cpuctx, task_ctx); | |
2574 | } | |
2575 | ||
0793a61d | 2576 | /* |
cdd6c482 | 2577 | * Cross CPU call to install and enable a performance event |
682076ae | 2578 | * |
a096309b PZ |
2579 | * Very similar to remote_function() + event_function() but cannot assume that |
2580 | * things like ctx->is_active and cpuctx->task_ctx are set. | |
0793a61d | 2581 | */ |
fe4b04fa | 2582 | static int __perf_install_in_context(void *info) |
0793a61d | 2583 | { |
a096309b PZ |
2584 | struct perf_event *event = info; |
2585 | struct perf_event_context *ctx = event->ctx; | |
108b02cf | 2586 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
2c29ef0f | 2587 | struct perf_event_context *task_ctx = cpuctx->task_ctx; |
63cae12b | 2588 | bool reprogram = true; |
a096309b | 2589 | int ret = 0; |
0793a61d | 2590 | |
63b6da39 | 2591 | raw_spin_lock(&cpuctx->ctx.lock); |
39a43640 | 2592 | if (ctx->task) { |
b58f6b0d PZ |
2593 | raw_spin_lock(&ctx->lock); |
2594 | task_ctx = ctx; | |
a096309b | 2595 | |
63cae12b | 2596 | reprogram = (ctx->task == current); |
b58f6b0d | 2597 | |
39a43640 | 2598 | /* |
63cae12b PZ |
2599 | * If the task is running, it must be running on this CPU, |
2600 | * otherwise we cannot reprogram things. | |
2601 | * | |
2602 | * If its not running, we don't care, ctx->lock will | |
2603 | * serialize against it becoming runnable. | |
39a43640 | 2604 | */ |
63cae12b PZ |
2605 | if (task_curr(ctx->task) && !reprogram) { |
2606 | ret = -ESRCH; | |
2607 | goto unlock; | |
2608 | } | |
a096309b | 2609 | |
63cae12b | 2610 | WARN_ON_ONCE(reprogram && cpuctx->task_ctx && cpuctx->task_ctx != ctx); |
63b6da39 PZ |
2611 | } else if (task_ctx) { |
2612 | raw_spin_lock(&task_ctx->lock); | |
2c29ef0f | 2613 | } |
b58f6b0d | 2614 | |
33801b94 | 2615 | #ifdef CONFIG_CGROUP_PERF |
2616 | if (is_cgroup_event(event)) { | |
2617 | /* | |
2618 | * If the current cgroup doesn't match the event's | |
2619 | * cgroup, we should not try to schedule it. | |
2620 | */ | |
2621 | struct perf_cgroup *cgrp = perf_cgroup_from_task(current, ctx); | |
2622 | reprogram = cgroup_is_descendant(cgrp->css.cgroup, | |
2623 | event->cgrp->css.cgroup); | |
2624 | } | |
2625 | #endif | |
2626 | ||
63cae12b | 2627 | if (reprogram) { |
a096309b PZ |
2628 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
2629 | add_event_to_ctx(event, ctx); | |
487f05e1 | 2630 | ctx_resched(cpuctx, task_ctx, get_event_type(event)); |
a096309b PZ |
2631 | } else { |
2632 | add_event_to_ctx(event, ctx); | |
2633 | } | |
2634 | ||
63b6da39 | 2635 | unlock: |
2c29ef0f | 2636 | perf_ctx_unlock(cpuctx, task_ctx); |
fe4b04fa | 2637 | |
a096309b | 2638 | return ret; |
0793a61d TG |
2639 | } |
2640 | ||
8a58ddae AS |
2641 | static bool exclusive_event_installable(struct perf_event *event, |
2642 | struct perf_event_context *ctx); | |
2643 | ||
0793a61d | 2644 | /* |
a096309b PZ |
2645 | * Attach a performance event to a context. |
2646 | * | |
2647 | * Very similar to event_function_call, see comment there. | |
0793a61d TG |
2648 | */ |
2649 | static void | |
cdd6c482 IM |
2650 | perf_install_in_context(struct perf_event_context *ctx, |
2651 | struct perf_event *event, | |
0793a61d TG |
2652 | int cpu) |
2653 | { | |
a096309b | 2654 | struct task_struct *task = READ_ONCE(ctx->task); |
39a43640 | 2655 | |
fe4b04fa PZ |
2656 | lockdep_assert_held(&ctx->mutex); |
2657 | ||
8a58ddae AS |
2658 | WARN_ON_ONCE(!exclusive_event_installable(event, ctx)); |
2659 | ||
0cda4c02 YZ |
2660 | if (event->cpu != -1) |
2661 | event->cpu = cpu; | |
c3f00c70 | 2662 | |
0b8f1e2e PZ |
2663 | /* |
2664 | * Ensures that if we can observe event->ctx, both the event and ctx | |
2665 | * will be 'complete'. See perf_iterate_sb_cpu(). | |
2666 | */ | |
2667 | smp_store_release(&event->ctx, ctx); | |
2668 | ||
db0503e4 PZ |
2669 | /* |
2670 | * perf_event_attr::disabled events will not run and can be initialized | |
2671 | * without IPI. Except when this is the first event for the context, in | |
2672 | * that case we need the magic of the IPI to set ctx->is_active. | |
2673 | * | |
2674 | * The IOC_ENABLE that is sure to follow the creation of a disabled | |
2675 | * event will issue the IPI and reprogram the hardware. | |
2676 | */ | |
2677 | if (__perf_effective_state(event) == PERF_EVENT_STATE_OFF && ctx->nr_events) { | |
2678 | raw_spin_lock_irq(&ctx->lock); | |
2679 | if (ctx->task == TASK_TOMBSTONE) { | |
2680 | raw_spin_unlock_irq(&ctx->lock); | |
2681 | return; | |
2682 | } | |
2683 | add_event_to_ctx(event, ctx); | |
2684 | raw_spin_unlock_irq(&ctx->lock); | |
2685 | return; | |
2686 | } | |
2687 | ||
a096309b PZ |
2688 | if (!task) { |
2689 | cpu_function_call(cpu, __perf_install_in_context, event); | |
2690 | return; | |
2691 | } | |
2692 | ||
2693 | /* | |
2694 | * Should not happen, we validate the ctx is still alive before calling. | |
2695 | */ | |
2696 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) | |
2697 | return; | |
2698 | ||
39a43640 PZ |
2699 | /* |
2700 | * Installing events is tricky because we cannot rely on ctx->is_active | |
2701 | * to be set in case this is the nr_events 0 -> 1 transition. | |
63cae12b PZ |
2702 | * |
2703 | * Instead we use task_curr(), which tells us if the task is running. | |
2704 | * However, since we use task_curr() outside of rq::lock, we can race | |
2705 | * against the actual state. This means the result can be wrong. | |
2706 | * | |
2707 | * If we get a false positive, we retry, this is harmless. | |
2708 | * | |
2709 | * If we get a false negative, things are complicated. If we are after | |
2710 | * perf_event_context_sched_in() ctx::lock will serialize us, and the | |
2711 | * value must be correct. If we're before, it doesn't matter since | |
2712 | * perf_event_context_sched_in() will program the counter. | |
2713 | * | |
2714 | * However, this hinges on the remote context switch having observed | |
2715 | * our task->perf_event_ctxp[] store, such that it will in fact take | |
2716 | * ctx::lock in perf_event_context_sched_in(). | |
2717 | * | |
2718 | * We do this by task_function_call(), if the IPI fails to hit the task | |
2719 | * we know any future context switch of task must see the | |
2720 | * perf_event_ctpx[] store. | |
39a43640 | 2721 | */ |
63cae12b | 2722 | |
63b6da39 | 2723 | /* |
63cae12b PZ |
2724 | * This smp_mb() orders the task->perf_event_ctxp[] store with the |
2725 | * task_cpu() load, such that if the IPI then does not find the task | |
2726 | * running, a future context switch of that task must observe the | |
2727 | * store. | |
63b6da39 | 2728 | */ |
63cae12b PZ |
2729 | smp_mb(); |
2730 | again: | |
2731 | if (!task_function_call(task, __perf_install_in_context, event)) | |
a096309b PZ |
2732 | return; |
2733 | ||
2734 | raw_spin_lock_irq(&ctx->lock); | |
2735 | task = ctx->task; | |
84c4e620 | 2736 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) { |
a096309b PZ |
2737 | /* |
2738 | * Cannot happen because we already checked above (which also | |
2739 | * cannot happen), and we hold ctx->mutex, which serializes us | |
2740 | * against perf_event_exit_task_context(). | |
2741 | */ | |
63b6da39 PZ |
2742 | raw_spin_unlock_irq(&ctx->lock); |
2743 | return; | |
2744 | } | |
39a43640 | 2745 | /* |
63cae12b PZ |
2746 | * If the task is not running, ctx->lock will avoid it becoming so, |
2747 | * thus we can safely install the event. | |
39a43640 | 2748 | */ |
63cae12b PZ |
2749 | if (task_curr(task)) { |
2750 | raw_spin_unlock_irq(&ctx->lock); | |
2751 | goto again; | |
2752 | } | |
2753 | add_event_to_ctx(event, ctx); | |
2754 | raw_spin_unlock_irq(&ctx->lock); | |
0793a61d TG |
2755 | } |
2756 | ||
d859e29f | 2757 | /* |
cdd6c482 | 2758 | * Cross CPU call to enable a performance event |
d859e29f | 2759 | */ |
fae3fde6 PZ |
2760 | static void __perf_event_enable(struct perf_event *event, |
2761 | struct perf_cpu_context *cpuctx, | |
2762 | struct perf_event_context *ctx, | |
2763 | void *info) | |
04289bb9 | 2764 | { |
cdd6c482 | 2765 | struct perf_event *leader = event->group_leader; |
fae3fde6 | 2766 | struct perf_event_context *task_ctx; |
04289bb9 | 2767 | |
6e801e01 PZ |
2768 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2769 | event->state <= PERF_EVENT_STATE_ERROR) | |
fae3fde6 | 2770 | return; |
3cbed429 | 2771 | |
bd2afa49 PZ |
2772 | if (ctx->is_active) |
2773 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); | |
2774 | ||
0d3d73aa | 2775 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
04289bb9 | 2776 | |
fae3fde6 PZ |
2777 | if (!ctx->is_active) |
2778 | return; | |
2779 | ||
e5d1367f | 2780 | if (!event_filter_match(event)) { |
bd2afa49 | 2781 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); |
fae3fde6 | 2782 | return; |
e5d1367f | 2783 | } |
f4c4176f | 2784 | |
04289bb9 | 2785 | /* |
cdd6c482 | 2786 | * If the event is in a group and isn't the group leader, |
d859e29f | 2787 | * then don't put it on unless the group is on. |
04289bb9 | 2788 | */ |
bd2afa49 PZ |
2789 | if (leader != event && leader->state != PERF_EVENT_STATE_ACTIVE) { |
2790 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
fae3fde6 | 2791 | return; |
bd2afa49 | 2792 | } |
fe4b04fa | 2793 | |
fae3fde6 PZ |
2794 | task_ctx = cpuctx->task_ctx; |
2795 | if (ctx->task) | |
2796 | WARN_ON_ONCE(task_ctx != ctx); | |
d859e29f | 2797 | |
487f05e1 | 2798 | ctx_resched(cpuctx, task_ctx, get_event_type(event)); |
7b648018 PZ |
2799 | } |
2800 | ||
d859e29f | 2801 | /* |
788faab7 | 2802 | * Enable an event. |
c93f7669 | 2803 | * |
cdd6c482 IM |
2804 | * If event->ctx is a cloned context, callers must make sure that |
2805 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 2806 | * remains valid. This condition is satisfied when called through |
cdd6c482 IM |
2807 | * perf_event_for_each_child or perf_event_for_each as described |
2808 | * for perf_event_disable. | |
d859e29f | 2809 | */ |
f63a8daa | 2810 | static void _perf_event_enable(struct perf_event *event) |
d859e29f | 2811 | { |
cdd6c482 | 2812 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 2813 | |
7b648018 | 2814 | raw_spin_lock_irq(&ctx->lock); |
6e801e01 PZ |
2815 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2816 | event->state < PERF_EVENT_STATE_ERROR) { | |
7b648018 | 2817 | raw_spin_unlock_irq(&ctx->lock); |
d859e29f PM |
2818 | return; |
2819 | } | |
2820 | ||
d859e29f | 2821 | /* |
cdd6c482 | 2822 | * If the event is in error state, clear that first. |
7b648018 PZ |
2823 | * |
2824 | * That way, if we see the event in error state below, we know that it | |
2825 | * has gone back into error state, as distinct from the task having | |
2826 | * been scheduled away before the cross-call arrived. | |
d859e29f | 2827 | */ |
cdd6c482 IM |
2828 | if (event->state == PERF_EVENT_STATE_ERROR) |
2829 | event->state = PERF_EVENT_STATE_OFF; | |
e625cce1 | 2830 | raw_spin_unlock_irq(&ctx->lock); |
fe4b04fa | 2831 | |
fae3fde6 | 2832 | event_function_call(event, __perf_event_enable, NULL); |
d859e29f | 2833 | } |
f63a8daa PZ |
2834 | |
2835 | /* | |
2836 | * See perf_event_disable(); | |
2837 | */ | |
2838 | void perf_event_enable(struct perf_event *event) | |
2839 | { | |
2840 | struct perf_event_context *ctx; | |
2841 | ||
2842 | ctx = perf_event_ctx_lock(event); | |
2843 | _perf_event_enable(event); | |
2844 | perf_event_ctx_unlock(event, ctx); | |
2845 | } | |
dcfce4a0 | 2846 | EXPORT_SYMBOL_GPL(perf_event_enable); |
d859e29f | 2847 | |
375637bc AS |
2848 | struct stop_event_data { |
2849 | struct perf_event *event; | |
2850 | unsigned int restart; | |
2851 | }; | |
2852 | ||
95ff4ca2 AS |
2853 | static int __perf_event_stop(void *info) |
2854 | { | |
375637bc AS |
2855 | struct stop_event_data *sd = info; |
2856 | struct perf_event *event = sd->event; | |
95ff4ca2 | 2857 | |
375637bc | 2858 | /* if it's already INACTIVE, do nothing */ |
95ff4ca2 AS |
2859 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) |
2860 | return 0; | |
2861 | ||
2862 | /* matches smp_wmb() in event_sched_in() */ | |
2863 | smp_rmb(); | |
2864 | ||
2865 | /* | |
2866 | * There is a window with interrupts enabled before we get here, | |
2867 | * so we need to check again lest we try to stop another CPU's event. | |
2868 | */ | |
2869 | if (READ_ONCE(event->oncpu) != smp_processor_id()) | |
2870 | return -EAGAIN; | |
2871 | ||
2872 | event->pmu->stop(event, PERF_EF_UPDATE); | |
2873 | ||
375637bc AS |
2874 | /* |
2875 | * May race with the actual stop (through perf_pmu_output_stop()), | |
2876 | * but it is only used for events with AUX ring buffer, and such | |
2877 | * events will refuse to restart because of rb::aux_mmap_count==0, | |
2878 | * see comments in perf_aux_output_begin(). | |
2879 | * | |
788faab7 | 2880 | * Since this is happening on an event-local CPU, no trace is lost |
375637bc AS |
2881 | * while restarting. |
2882 | */ | |
2883 | if (sd->restart) | |
c9bbdd48 | 2884 | event->pmu->start(event, 0); |
375637bc | 2885 | |
95ff4ca2 AS |
2886 | return 0; |
2887 | } | |
2888 | ||
767ae086 | 2889 | static int perf_event_stop(struct perf_event *event, int restart) |
375637bc AS |
2890 | { |
2891 | struct stop_event_data sd = { | |
2892 | .event = event, | |
767ae086 | 2893 | .restart = restart, |
375637bc AS |
2894 | }; |
2895 | int ret = 0; | |
2896 | ||
2897 | do { | |
2898 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) | |
2899 | return 0; | |
2900 | ||
2901 | /* matches smp_wmb() in event_sched_in() */ | |
2902 | smp_rmb(); | |
2903 | ||
2904 | /* | |
2905 | * We only want to restart ACTIVE events, so if the event goes | |
2906 | * inactive here (event->oncpu==-1), there's nothing more to do; | |
2907 | * fall through with ret==-ENXIO. | |
2908 | */ | |
2909 | ret = cpu_function_call(READ_ONCE(event->oncpu), | |
2910 | __perf_event_stop, &sd); | |
2911 | } while (ret == -EAGAIN); | |
2912 | ||
2913 | return ret; | |
2914 | } | |
2915 | ||
2916 | /* | |
2917 | * In order to contain the amount of racy and tricky in the address filter | |
2918 | * configuration management, it is a two part process: | |
2919 | * | |
2920 | * (p1) when userspace mappings change as a result of (1) or (2) or (3) below, | |
2921 | * we update the addresses of corresponding vmas in | |
c60f83b8 | 2922 | * event::addr_filter_ranges array and bump the event::addr_filters_gen; |
375637bc AS |
2923 | * (p2) when an event is scheduled in (pmu::add), it calls |
2924 | * perf_event_addr_filters_sync() which calls pmu::addr_filters_sync() | |
2925 | * if the generation has changed since the previous call. | |
2926 | * | |
2927 | * If (p1) happens while the event is active, we restart it to force (p2). | |
2928 | * | |
2929 | * (1) perf_addr_filters_apply(): adjusting filters' offsets based on | |
2930 | * pre-existing mappings, called once when new filters arrive via SET_FILTER | |
2931 | * ioctl; | |
2932 | * (2) perf_addr_filters_adjust(): adjusting filters' offsets based on newly | |
2933 | * registered mapping, called for every new mmap(), with mm::mmap_sem down | |
2934 | * for reading; | |
2935 | * (3) perf_event_addr_filters_exec(): clearing filters' offsets in the process | |
2936 | * of exec. | |
2937 | */ | |
2938 | void perf_event_addr_filters_sync(struct perf_event *event) | |
2939 | { | |
2940 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
2941 | ||
2942 | if (!has_addr_filter(event)) | |
2943 | return; | |
2944 | ||
2945 | raw_spin_lock(&ifh->lock); | |
2946 | if (event->addr_filters_gen != event->hw.addr_filters_gen) { | |
2947 | event->pmu->addr_filters_sync(event); | |
2948 | event->hw.addr_filters_gen = event->addr_filters_gen; | |
2949 | } | |
2950 | raw_spin_unlock(&ifh->lock); | |
2951 | } | |
2952 | EXPORT_SYMBOL_GPL(perf_event_addr_filters_sync); | |
2953 | ||
f63a8daa | 2954 | static int _perf_event_refresh(struct perf_event *event, int refresh) |
79f14641 | 2955 | { |
2023b359 | 2956 | /* |
cdd6c482 | 2957 | * not supported on inherited events |
2023b359 | 2958 | */ |
2e939d1d | 2959 | if (event->attr.inherit || !is_sampling_event(event)) |
2023b359 PZ |
2960 | return -EINVAL; |
2961 | ||
cdd6c482 | 2962 | atomic_add(refresh, &event->event_limit); |
f63a8daa | 2963 | _perf_event_enable(event); |
2023b359 PZ |
2964 | |
2965 | return 0; | |
79f14641 | 2966 | } |
f63a8daa PZ |
2967 | |
2968 | /* | |
2969 | * See perf_event_disable() | |
2970 | */ | |
2971 | int perf_event_refresh(struct perf_event *event, int refresh) | |
2972 | { | |
2973 | struct perf_event_context *ctx; | |
2974 | int ret; | |
2975 | ||
2976 | ctx = perf_event_ctx_lock(event); | |
2977 | ret = _perf_event_refresh(event, refresh); | |
2978 | perf_event_ctx_unlock(event, ctx); | |
2979 | ||
2980 | return ret; | |
2981 | } | |
26ca5c11 | 2982 | EXPORT_SYMBOL_GPL(perf_event_refresh); |
79f14641 | 2983 | |
32ff77e8 MC |
2984 | static int perf_event_modify_breakpoint(struct perf_event *bp, |
2985 | struct perf_event_attr *attr) | |
2986 | { | |
2987 | int err; | |
2988 | ||
2989 | _perf_event_disable(bp); | |
2990 | ||
2991 | err = modify_user_hw_breakpoint_check(bp, attr, true); | |
32ff77e8 | 2992 | |
bf06278c | 2993 | if (!bp->attr.disabled) |
32ff77e8 | 2994 | _perf_event_enable(bp); |
bf06278c JO |
2995 | |
2996 | return err; | |
32ff77e8 MC |
2997 | } |
2998 | ||
2999 | static int perf_event_modify_attr(struct perf_event *event, | |
3000 | struct perf_event_attr *attr) | |
3001 | { | |
3002 | if (event->attr.type != attr->type) | |
3003 | return -EINVAL; | |
3004 | ||
3005 | switch (event->attr.type) { | |
3006 | case PERF_TYPE_BREAKPOINT: | |
3007 | return perf_event_modify_breakpoint(event, attr); | |
3008 | default: | |
3009 | /* Place holder for future additions. */ | |
3010 | return -EOPNOTSUPP; | |
3011 | } | |
3012 | } | |
3013 | ||
5b0311e1 FW |
3014 | static void ctx_sched_out(struct perf_event_context *ctx, |
3015 | struct perf_cpu_context *cpuctx, | |
3016 | enum event_type_t event_type) | |
235c7fc7 | 3017 | { |
6668128a | 3018 | struct perf_event *event, *tmp; |
db24d33e | 3019 | int is_active = ctx->is_active; |
235c7fc7 | 3020 | |
c994d613 | 3021 | lockdep_assert_held(&ctx->lock); |
235c7fc7 | 3022 | |
39a43640 PZ |
3023 | if (likely(!ctx->nr_events)) { |
3024 | /* | |
3025 | * See __perf_remove_from_context(). | |
3026 | */ | |
3027 | WARN_ON_ONCE(ctx->is_active); | |
3028 | if (ctx->task) | |
3029 | WARN_ON_ONCE(cpuctx->task_ctx); | |
facc4307 | 3030 | return; |
39a43640 PZ |
3031 | } |
3032 | ||
db24d33e | 3033 | ctx->is_active &= ~event_type; |
3cbaa590 PZ |
3034 | if (!(ctx->is_active & EVENT_ALL)) |
3035 | ctx->is_active = 0; | |
3036 | ||
63e30d3e PZ |
3037 | if (ctx->task) { |
3038 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
3039 | if (!ctx->is_active) | |
3040 | cpuctx->task_ctx = NULL; | |
3041 | } | |
facc4307 | 3042 | |
8fdc6539 PZ |
3043 | /* |
3044 | * Always update time if it was set; not only when it changes. | |
3045 | * Otherwise we can 'forget' to update time for any but the last | |
3046 | * context we sched out. For example: | |
3047 | * | |
3048 | * ctx_sched_out(.event_type = EVENT_FLEXIBLE) | |
3049 | * ctx_sched_out(.event_type = EVENT_PINNED) | |
3050 | * | |
3051 | * would only update time for the pinned events. | |
3052 | */ | |
3cbaa590 PZ |
3053 | if (is_active & EVENT_TIME) { |
3054 | /* update (and stop) ctx time */ | |
3055 | update_context_time(ctx); | |
3056 | update_cgrp_time_from_cpuctx(cpuctx); | |
3057 | } | |
3058 | ||
8fdc6539 PZ |
3059 | is_active ^= ctx->is_active; /* changed bits */ |
3060 | ||
3cbaa590 | 3061 | if (!ctx->nr_active || !(is_active & EVENT_ALL)) |
facc4307 | 3062 | return; |
5b0311e1 | 3063 | |
fd7d5517 IR |
3064 | /* |
3065 | * If we had been multiplexing, no rotations are necessary, now no events | |
3066 | * are active. | |
3067 | */ | |
3068 | ctx->rotate_necessary = 0; | |
3069 | ||
075e0b00 | 3070 | perf_pmu_disable(ctx->pmu); |
3cbaa590 | 3071 | if (is_active & EVENT_PINNED) { |
6668128a | 3072 | list_for_each_entry_safe(event, tmp, &ctx->pinned_active, active_list) |
889ff015 | 3073 | group_sched_out(event, cpuctx, ctx); |
9ed6060d | 3074 | } |
889ff015 | 3075 | |
3cbaa590 | 3076 | if (is_active & EVENT_FLEXIBLE) { |
6668128a | 3077 | list_for_each_entry_safe(event, tmp, &ctx->flexible_active, active_list) |
8c9ed8e1 | 3078 | group_sched_out(event, cpuctx, ctx); |
9ed6060d | 3079 | } |
1b9a644f | 3080 | perf_pmu_enable(ctx->pmu); |
235c7fc7 IM |
3081 | } |
3082 | ||
564c2b21 | 3083 | /* |
5a3126d4 PZ |
3084 | * Test whether two contexts are equivalent, i.e. whether they have both been |
3085 | * cloned from the same version of the same context. | |
3086 | * | |
3087 | * Equivalence is measured using a generation number in the context that is | |
3088 | * incremented on each modification to it; see unclone_ctx(), list_add_event() | |
3089 | * and list_del_event(). | |
564c2b21 | 3090 | */ |
cdd6c482 IM |
3091 | static int context_equiv(struct perf_event_context *ctx1, |
3092 | struct perf_event_context *ctx2) | |
564c2b21 | 3093 | { |
211de6eb PZ |
3094 | lockdep_assert_held(&ctx1->lock); |
3095 | lockdep_assert_held(&ctx2->lock); | |
3096 | ||
5a3126d4 PZ |
3097 | /* Pinning disables the swap optimization */ |
3098 | if (ctx1->pin_count || ctx2->pin_count) | |
3099 | return 0; | |
3100 | ||
3101 | /* If ctx1 is the parent of ctx2 */ | |
3102 | if (ctx1 == ctx2->parent_ctx && ctx1->generation == ctx2->parent_gen) | |
3103 | return 1; | |
3104 | ||
3105 | /* If ctx2 is the parent of ctx1 */ | |
3106 | if (ctx1->parent_ctx == ctx2 && ctx1->parent_gen == ctx2->generation) | |
3107 | return 1; | |
3108 | ||
3109 | /* | |
3110 | * If ctx1 and ctx2 have the same parent; we flatten the parent | |
3111 | * hierarchy, see perf_event_init_context(). | |
3112 | */ | |
3113 | if (ctx1->parent_ctx && ctx1->parent_ctx == ctx2->parent_ctx && | |
3114 | ctx1->parent_gen == ctx2->parent_gen) | |
3115 | return 1; | |
3116 | ||
3117 | /* Unmatched */ | |
3118 | return 0; | |
564c2b21 PM |
3119 | } |
3120 | ||
cdd6c482 IM |
3121 | static void __perf_event_sync_stat(struct perf_event *event, |
3122 | struct perf_event *next_event) | |
bfbd3381 PZ |
3123 | { |
3124 | u64 value; | |
3125 | ||
cdd6c482 | 3126 | if (!event->attr.inherit_stat) |
bfbd3381 PZ |
3127 | return; |
3128 | ||
3129 | /* | |
cdd6c482 | 3130 | * Update the event value, we cannot use perf_event_read() |
bfbd3381 PZ |
3131 | * because we're in the middle of a context switch and have IRQs |
3132 | * disabled, which upsets smp_call_function_single(), however | |
cdd6c482 | 3133 | * we know the event must be on the current CPU, therefore we |
bfbd3381 PZ |
3134 | * don't need to use it. |
3135 | */ | |
0d3d73aa | 3136 | if (event->state == PERF_EVENT_STATE_ACTIVE) |
3dbebf15 | 3137 | event->pmu->read(event); |
bfbd3381 | 3138 | |
0d3d73aa | 3139 | perf_event_update_time(event); |
bfbd3381 PZ |
3140 | |
3141 | /* | |
cdd6c482 | 3142 | * In order to keep per-task stats reliable we need to flip the event |
bfbd3381 PZ |
3143 | * values when we flip the contexts. |
3144 | */ | |
e7850595 PZ |
3145 | value = local64_read(&next_event->count); |
3146 | value = local64_xchg(&event->count, value); | |
3147 | local64_set(&next_event->count, value); | |
bfbd3381 | 3148 | |
cdd6c482 IM |
3149 | swap(event->total_time_enabled, next_event->total_time_enabled); |
3150 | swap(event->total_time_running, next_event->total_time_running); | |
19d2e755 | 3151 | |
bfbd3381 | 3152 | /* |
19d2e755 | 3153 | * Since we swizzled the values, update the user visible data too. |
bfbd3381 | 3154 | */ |
cdd6c482 IM |
3155 | perf_event_update_userpage(event); |
3156 | perf_event_update_userpage(next_event); | |
bfbd3381 PZ |
3157 | } |
3158 | ||
cdd6c482 IM |
3159 | static void perf_event_sync_stat(struct perf_event_context *ctx, |
3160 | struct perf_event_context *next_ctx) | |
bfbd3381 | 3161 | { |
cdd6c482 | 3162 | struct perf_event *event, *next_event; |
bfbd3381 PZ |
3163 | |
3164 | if (!ctx->nr_stat) | |
3165 | return; | |
3166 | ||
02ffdbc8 PZ |
3167 | update_context_time(ctx); |
3168 | ||
cdd6c482 IM |
3169 | event = list_first_entry(&ctx->event_list, |
3170 | struct perf_event, event_entry); | |
bfbd3381 | 3171 | |
cdd6c482 IM |
3172 | next_event = list_first_entry(&next_ctx->event_list, |
3173 | struct perf_event, event_entry); | |
bfbd3381 | 3174 | |
cdd6c482 IM |
3175 | while (&event->event_entry != &ctx->event_list && |
3176 | &next_event->event_entry != &next_ctx->event_list) { | |
bfbd3381 | 3177 | |
cdd6c482 | 3178 | __perf_event_sync_stat(event, next_event); |
bfbd3381 | 3179 | |
cdd6c482 IM |
3180 | event = list_next_entry(event, event_entry); |
3181 | next_event = list_next_entry(next_event, event_entry); | |
bfbd3381 PZ |
3182 | } |
3183 | } | |
3184 | ||
fe4b04fa PZ |
3185 | static void perf_event_context_sched_out(struct task_struct *task, int ctxn, |
3186 | struct task_struct *next) | |
0793a61d | 3187 | { |
8dc85d54 | 3188 | struct perf_event_context *ctx = task->perf_event_ctxp[ctxn]; |
cdd6c482 | 3189 | struct perf_event_context *next_ctx; |
5a3126d4 | 3190 | struct perf_event_context *parent, *next_parent; |
108b02cf | 3191 | struct perf_cpu_context *cpuctx; |
c93f7669 | 3192 | int do_switch = 1; |
0793a61d | 3193 | |
108b02cf PZ |
3194 | if (likely(!ctx)) |
3195 | return; | |
10989fb2 | 3196 | |
108b02cf PZ |
3197 | cpuctx = __get_cpu_context(ctx); |
3198 | if (!cpuctx->task_ctx) | |
0793a61d TG |
3199 | return; |
3200 | ||
c93f7669 | 3201 | rcu_read_lock(); |
8dc85d54 | 3202 | next_ctx = next->perf_event_ctxp[ctxn]; |
5a3126d4 PZ |
3203 | if (!next_ctx) |
3204 | goto unlock; | |
3205 | ||
3206 | parent = rcu_dereference(ctx->parent_ctx); | |
3207 | next_parent = rcu_dereference(next_ctx->parent_ctx); | |
3208 | ||
3209 | /* If neither context have a parent context; they cannot be clones. */ | |
802c8a61 | 3210 | if (!parent && !next_parent) |
5a3126d4 PZ |
3211 | goto unlock; |
3212 | ||
3213 | if (next_parent == ctx || next_ctx == parent || next_parent == parent) { | |
c93f7669 PM |
3214 | /* |
3215 | * Looks like the two contexts are clones, so we might be | |
3216 | * able to optimize the context switch. We lock both | |
3217 | * contexts and check that they are clones under the | |
3218 | * lock (including re-checking that neither has been | |
3219 | * uncloned in the meantime). It doesn't matter which | |
3220 | * order we take the locks because no other cpu could | |
3221 | * be trying to lock both of these tasks. | |
3222 | */ | |
e625cce1 TG |
3223 | raw_spin_lock(&ctx->lock); |
3224 | raw_spin_lock_nested(&next_ctx->lock, SINGLE_DEPTH_NESTING); | |
c93f7669 | 3225 | if (context_equiv(ctx, next_ctx)) { |
c2b98a86 AB |
3226 | struct pmu *pmu = ctx->pmu; |
3227 | ||
63b6da39 PZ |
3228 | WRITE_ONCE(ctx->task, next); |
3229 | WRITE_ONCE(next_ctx->task, task); | |
5a158c3c | 3230 | |
c2b98a86 AB |
3231 | /* |
3232 | * PMU specific parts of task perf context can require | |
3233 | * additional synchronization. As an example of such | |
3234 | * synchronization see implementation details of Intel | |
3235 | * LBR call stack data profiling; | |
3236 | */ | |
3237 | if (pmu->swap_task_ctx) | |
3238 | pmu->swap_task_ctx(ctx, next_ctx); | |
3239 | else | |
3240 | swap(ctx->task_ctx_data, next_ctx->task_ctx_data); | |
5a158c3c | 3241 | |
63b6da39 PZ |
3242 | /* |
3243 | * RCU_INIT_POINTER here is safe because we've not | |
3244 | * modified the ctx and the above modification of | |
3245 | * ctx->task and ctx->task_ctx_data are immaterial | |
3246 | * since those values are always verified under | |
3247 | * ctx->lock which we're now holding. | |
3248 | */ | |
3249 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], next_ctx); | |
3250 | RCU_INIT_POINTER(next->perf_event_ctxp[ctxn], ctx); | |
3251 | ||
c93f7669 | 3252 | do_switch = 0; |
bfbd3381 | 3253 | |
cdd6c482 | 3254 | perf_event_sync_stat(ctx, next_ctx); |
c93f7669 | 3255 | } |
e625cce1 TG |
3256 | raw_spin_unlock(&next_ctx->lock); |
3257 | raw_spin_unlock(&ctx->lock); | |
564c2b21 | 3258 | } |
5a3126d4 | 3259 | unlock: |
c93f7669 | 3260 | rcu_read_unlock(); |
564c2b21 | 3261 | |
c93f7669 | 3262 | if (do_switch) { |
facc4307 | 3263 | raw_spin_lock(&ctx->lock); |
487f05e1 | 3264 | task_ctx_sched_out(cpuctx, ctx, EVENT_ALL); |
facc4307 | 3265 | raw_spin_unlock(&ctx->lock); |
c93f7669 | 3266 | } |
0793a61d TG |
3267 | } |
3268 | ||
e48c1788 PZ |
3269 | static DEFINE_PER_CPU(struct list_head, sched_cb_list); |
3270 | ||
ba532500 YZ |
3271 | void perf_sched_cb_dec(struct pmu *pmu) |
3272 | { | |
e48c1788 PZ |
3273 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
3274 | ||
ba532500 | 3275 | this_cpu_dec(perf_sched_cb_usages); |
e48c1788 PZ |
3276 | |
3277 | if (!--cpuctx->sched_cb_usage) | |
3278 | list_del(&cpuctx->sched_cb_entry); | |
ba532500 YZ |
3279 | } |
3280 | ||
e48c1788 | 3281 | |
ba532500 YZ |
3282 | void perf_sched_cb_inc(struct pmu *pmu) |
3283 | { | |
e48c1788 PZ |
3284 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
3285 | ||
3286 | if (!cpuctx->sched_cb_usage++) | |
3287 | list_add(&cpuctx->sched_cb_entry, this_cpu_ptr(&sched_cb_list)); | |
3288 | ||
ba532500 YZ |
3289 | this_cpu_inc(perf_sched_cb_usages); |
3290 | } | |
3291 | ||
3292 | /* | |
3293 | * This function provides the context switch callback to the lower code | |
3294 | * layer. It is invoked ONLY when the context switch callback is enabled. | |
09e61b4f PZ |
3295 | * |
3296 | * This callback is relevant even to per-cpu events; for example multi event | |
3297 | * PEBS requires this to provide PID/TID information. This requires we flush | |
3298 | * all queued PEBS records before we context switch to a new task. | |
ba532500 YZ |
3299 | */ |
3300 | static void perf_pmu_sched_task(struct task_struct *prev, | |
3301 | struct task_struct *next, | |
3302 | bool sched_in) | |
3303 | { | |
3304 | struct perf_cpu_context *cpuctx; | |
3305 | struct pmu *pmu; | |
ba532500 YZ |
3306 | |
3307 | if (prev == next) | |
3308 | return; | |
3309 | ||
e48c1788 | 3310 | list_for_each_entry(cpuctx, this_cpu_ptr(&sched_cb_list), sched_cb_entry) { |
1fd7e416 | 3311 | pmu = cpuctx->ctx.pmu; /* software PMUs will not have sched_task */ |
ba532500 | 3312 | |
e48c1788 PZ |
3313 | if (WARN_ON_ONCE(!pmu->sched_task)) |
3314 | continue; | |
ba532500 | 3315 | |
e48c1788 PZ |
3316 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
3317 | perf_pmu_disable(pmu); | |
ba532500 | 3318 | |
e48c1788 | 3319 | pmu->sched_task(cpuctx->task_ctx, sched_in); |
ba532500 | 3320 | |
e48c1788 PZ |
3321 | perf_pmu_enable(pmu); |
3322 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
ba532500 | 3323 | } |
ba532500 YZ |
3324 | } |
3325 | ||
45ac1403 AH |
3326 | static void perf_event_switch(struct task_struct *task, |
3327 | struct task_struct *next_prev, bool sched_in); | |
3328 | ||
8dc85d54 PZ |
3329 | #define for_each_task_context_nr(ctxn) \ |
3330 | for ((ctxn) = 0; (ctxn) < perf_nr_task_contexts; (ctxn)++) | |
3331 | ||
3332 | /* | |
3333 | * Called from scheduler to remove the events of the current task, | |
3334 | * with interrupts disabled. | |
3335 | * | |
3336 | * We stop each event and update the event value in event->count. | |
3337 | * | |
3338 | * This does not protect us against NMI, but disable() | |
3339 | * sets the disabled bit in the control field of event _before_ | |
3340 | * accessing the event control register. If a NMI hits, then it will | |
3341 | * not restart the event. | |
3342 | */ | |
ab0cce56 JO |
3343 | void __perf_event_task_sched_out(struct task_struct *task, |
3344 | struct task_struct *next) | |
8dc85d54 PZ |
3345 | { |
3346 | int ctxn; | |
3347 | ||
ba532500 YZ |
3348 | if (__this_cpu_read(perf_sched_cb_usages)) |
3349 | perf_pmu_sched_task(task, next, false); | |
3350 | ||
45ac1403 AH |
3351 | if (atomic_read(&nr_switch_events)) |
3352 | perf_event_switch(task, next, false); | |
3353 | ||
8dc85d54 PZ |
3354 | for_each_task_context_nr(ctxn) |
3355 | perf_event_context_sched_out(task, ctxn, next); | |
e5d1367f SE |
3356 | |
3357 | /* | |
3358 | * if cgroup events exist on this CPU, then we need | |
3359 | * to check if we have to switch out PMU state. | |
3360 | * cgroup event are system-wide mode only | |
3361 | */ | |
4a32fea9 | 3362 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) |
a8d757ef | 3363 | perf_cgroup_sched_out(task, next); |
8dc85d54 PZ |
3364 | } |
3365 | ||
5b0311e1 FW |
3366 | /* |
3367 | * Called with IRQs disabled | |
3368 | */ | |
3369 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, | |
3370 | enum event_type_t event_type) | |
3371 | { | |
3372 | ctx_sched_out(&cpuctx->ctx, cpuctx, event_type); | |
04289bb9 IM |
3373 | } |
3374 | ||
1cac7b1a PZ |
3375 | static int visit_groups_merge(struct perf_event_groups *groups, int cpu, |
3376 | int (*func)(struct perf_event *, void *), void *data) | |
0793a61d | 3377 | { |
1cac7b1a PZ |
3378 | struct perf_event **evt, *evt1, *evt2; |
3379 | int ret; | |
8e1a2031 | 3380 | |
1cac7b1a PZ |
3381 | evt1 = perf_event_groups_first(groups, -1); |
3382 | evt2 = perf_event_groups_first(groups, cpu); | |
3383 | ||
3384 | while (evt1 || evt2) { | |
3385 | if (evt1 && evt2) { | |
3386 | if (evt1->group_index < evt2->group_index) | |
3387 | evt = &evt1; | |
3388 | else | |
3389 | evt = &evt2; | |
3390 | } else if (evt1) { | |
3391 | evt = &evt1; | |
3392 | } else { | |
3393 | evt = &evt2; | |
8e1a2031 | 3394 | } |
1cac7b1a PZ |
3395 | |
3396 | ret = func(*evt, data); | |
3397 | if (ret) | |
3398 | return ret; | |
3399 | ||
3400 | *evt = perf_event_groups_next(*evt); | |
8e1a2031 | 3401 | } |
0793a61d | 3402 | |
1cac7b1a PZ |
3403 | return 0; |
3404 | } | |
3405 | ||
3406 | struct sched_in_data { | |
3407 | struct perf_event_context *ctx; | |
3408 | struct perf_cpu_context *cpuctx; | |
3409 | int can_add_hw; | |
3410 | }; | |
3411 | ||
3412 | static int pinned_sched_in(struct perf_event *event, void *data) | |
3413 | { | |
3414 | struct sched_in_data *sid = data; | |
3415 | ||
3416 | if (event->state <= PERF_EVENT_STATE_OFF) | |
3417 | return 0; | |
3418 | ||
3419 | if (!event_filter_match(event)) | |
3420 | return 0; | |
3421 | ||
6668128a PZ |
3422 | if (group_can_go_on(event, sid->cpuctx, sid->can_add_hw)) { |
3423 | if (!group_sched_in(event, sid->cpuctx, sid->ctx)) | |
3424 | list_add_tail(&event->active_list, &sid->ctx->pinned_active); | |
3425 | } | |
1cac7b1a PZ |
3426 | |
3427 | /* | |
3428 | * If this pinned group hasn't been scheduled, | |
3429 | * put it in error state. | |
3430 | */ | |
3431 | if (event->state == PERF_EVENT_STATE_INACTIVE) | |
3432 | perf_event_set_state(event, PERF_EVENT_STATE_ERROR); | |
3433 | ||
3434 | return 0; | |
3435 | } | |
3436 | ||
3437 | static int flexible_sched_in(struct perf_event *event, void *data) | |
3438 | { | |
3439 | struct sched_in_data *sid = data; | |
3440 | ||
3441 | if (event->state <= PERF_EVENT_STATE_OFF) | |
3442 | return 0; | |
3443 | ||
3444 | if (!event_filter_match(event)) | |
3445 | return 0; | |
3446 | ||
3447 | if (group_can_go_on(event, sid->cpuctx, sid->can_add_hw)) { | |
fd7d5517 IR |
3448 | int ret = group_sched_in(event, sid->cpuctx, sid->ctx); |
3449 | if (ret) { | |
1cac7b1a | 3450 | sid->can_add_hw = 0; |
fd7d5517 IR |
3451 | sid->ctx->rotate_necessary = 1; |
3452 | return 0; | |
3453 | } | |
3454 | list_add_tail(&event->active_list, &sid->ctx->flexible_active); | |
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(), | |
3472 | pinned_sched_in, &sid); | |
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(), | |
3487 | flexible_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 PZ |
4360 | static void ring_buffer_attach(struct perf_event *event, |
4361 | struct ring_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; |
76369139 | 5042 | struct ring_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 | ||
c93f7669 | 5069 | /* |
cdd6c482 IM |
5070 | * Holding the top-level event's child_mutex means that any |
5071 | * descendant process that has inherited this event will block | |
8ba289b8 | 5072 | * in perf_event_exit_event() if it goes to exit, thus satisfying the |
cdd6c482 | 5073 | * task existence requirements of perf_event_enable/disable. |
c93f7669 | 5074 | */ |
cdd6c482 IM |
5075 | static void perf_event_for_each_child(struct perf_event *event, |
5076 | void (*func)(struct perf_event *)) | |
3df5edad | 5077 | { |
cdd6c482 | 5078 | struct perf_event *child; |
3df5edad | 5079 | |
cdd6c482 | 5080 | WARN_ON_ONCE(event->ctx->parent_ctx); |
f63a8daa | 5081 | |
cdd6c482 IM |
5082 | mutex_lock(&event->child_mutex); |
5083 | func(event); | |
5084 | list_for_each_entry(child, &event->child_list, child_list) | |
3df5edad | 5085 | func(child); |
cdd6c482 | 5086 | mutex_unlock(&event->child_mutex); |
3df5edad PZ |
5087 | } |
5088 | ||
cdd6c482 IM |
5089 | static void perf_event_for_each(struct perf_event *event, |
5090 | void (*func)(struct perf_event *)) | |
3df5edad | 5091 | { |
cdd6c482 IM |
5092 | struct perf_event_context *ctx = event->ctx; |
5093 | struct perf_event *sibling; | |
3df5edad | 5094 | |
f63a8daa PZ |
5095 | lockdep_assert_held(&ctx->mutex); |
5096 | ||
cdd6c482 | 5097 | event = event->group_leader; |
75f937f2 | 5098 | |
cdd6c482 | 5099 | perf_event_for_each_child(event, func); |
edb39592 | 5100 | for_each_sibling_event(sibling, event) |
724b6daa | 5101 | perf_event_for_each_child(sibling, func); |
6de6a7b9 PZ |
5102 | } |
5103 | ||
fae3fde6 PZ |
5104 | static void __perf_event_period(struct perf_event *event, |
5105 | struct perf_cpu_context *cpuctx, | |
5106 | struct perf_event_context *ctx, | |
5107 | void *info) | |
c7999c6f | 5108 | { |
fae3fde6 | 5109 | u64 value = *((u64 *)info); |
c7999c6f | 5110 | bool active; |
08247e31 | 5111 | |
cdd6c482 | 5112 | if (event->attr.freq) { |
cdd6c482 | 5113 | event->attr.sample_freq = value; |
08247e31 | 5114 | } else { |
cdd6c482 IM |
5115 | event->attr.sample_period = value; |
5116 | event->hw.sample_period = value; | |
08247e31 | 5117 | } |
bad7192b PZ |
5118 | |
5119 | active = (event->state == PERF_EVENT_STATE_ACTIVE); | |
5120 | if (active) { | |
5121 | perf_pmu_disable(ctx->pmu); | |
1e02cd40 PZ |
5122 | /* |
5123 | * We could be throttled; unthrottle now to avoid the tick | |
5124 | * trying to unthrottle while we already re-started the event. | |
5125 | */ | |
5126 | if (event->hw.interrupts == MAX_INTERRUPTS) { | |
5127 | event->hw.interrupts = 0; | |
5128 | perf_log_throttle(event, 1); | |
5129 | } | |
bad7192b PZ |
5130 | event->pmu->stop(event, PERF_EF_UPDATE); |
5131 | } | |
5132 | ||
5133 | local64_set(&event->hw.period_left, 0); | |
5134 | ||
5135 | if (active) { | |
5136 | event->pmu->start(event, PERF_EF_RELOAD); | |
5137 | perf_pmu_enable(ctx->pmu); | |
5138 | } | |
c7999c6f PZ |
5139 | } |
5140 | ||
81ec3f3c JO |
5141 | static int perf_event_check_period(struct perf_event *event, u64 value) |
5142 | { | |
5143 | return event->pmu->check_period(event, value); | |
5144 | } | |
5145 | ||
c7999c6f PZ |
5146 | static int perf_event_period(struct perf_event *event, u64 __user *arg) |
5147 | { | |
c7999c6f PZ |
5148 | u64 value; |
5149 | ||
5150 | if (!is_sampling_event(event)) | |
5151 | return -EINVAL; | |
5152 | ||
5153 | if (copy_from_user(&value, arg, sizeof(value))) | |
5154 | return -EFAULT; | |
5155 | ||
5156 | if (!value) | |
5157 | return -EINVAL; | |
5158 | ||
5159 | if (event->attr.freq && value > sysctl_perf_event_sample_rate) | |
5160 | return -EINVAL; | |
5161 | ||
81ec3f3c JO |
5162 | if (perf_event_check_period(event, value)) |
5163 | return -EINVAL; | |
5164 | ||
913a90bc RB |
5165 | if (!event->attr.freq && (value & (1ULL << 63))) |
5166 | return -EINVAL; | |
5167 | ||
fae3fde6 | 5168 | event_function_call(event, __perf_event_period, &value); |
08247e31 | 5169 | |
c7999c6f | 5170 | return 0; |
08247e31 PZ |
5171 | } |
5172 | ||
ac9721f3 PZ |
5173 | static const struct file_operations perf_fops; |
5174 | ||
2903ff01 | 5175 | static inline int perf_fget_light(int fd, struct fd *p) |
ac9721f3 | 5176 | { |
2903ff01 AV |
5177 | struct fd f = fdget(fd); |
5178 | if (!f.file) | |
5179 | return -EBADF; | |
ac9721f3 | 5180 | |
2903ff01 AV |
5181 | if (f.file->f_op != &perf_fops) { |
5182 | fdput(f); | |
5183 | return -EBADF; | |
ac9721f3 | 5184 | } |
2903ff01 AV |
5185 | *p = f; |
5186 | return 0; | |
ac9721f3 PZ |
5187 | } |
5188 | ||
5189 | static int perf_event_set_output(struct perf_event *event, | |
5190 | struct perf_event *output_event); | |
6fb2915d | 5191 | static int perf_event_set_filter(struct perf_event *event, void __user *arg); |
2541517c | 5192 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd); |
32ff77e8 MC |
5193 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
5194 | struct perf_event_attr *attr); | |
a4be7c27 | 5195 | |
f63a8daa | 5196 | static long _perf_ioctl(struct perf_event *event, unsigned int cmd, unsigned long arg) |
d859e29f | 5197 | { |
cdd6c482 | 5198 | void (*func)(struct perf_event *); |
3df5edad | 5199 | u32 flags = arg; |
d859e29f PM |
5200 | |
5201 | switch (cmd) { | |
cdd6c482 | 5202 | case PERF_EVENT_IOC_ENABLE: |
f63a8daa | 5203 | func = _perf_event_enable; |
d859e29f | 5204 | break; |
cdd6c482 | 5205 | case PERF_EVENT_IOC_DISABLE: |
f63a8daa | 5206 | func = _perf_event_disable; |
79f14641 | 5207 | break; |
cdd6c482 | 5208 | case PERF_EVENT_IOC_RESET: |
f63a8daa | 5209 | func = _perf_event_reset; |
6de6a7b9 | 5210 | break; |
3df5edad | 5211 | |
cdd6c482 | 5212 | case PERF_EVENT_IOC_REFRESH: |
f63a8daa | 5213 | return _perf_event_refresh(event, arg); |
08247e31 | 5214 | |
cdd6c482 IM |
5215 | case PERF_EVENT_IOC_PERIOD: |
5216 | return perf_event_period(event, (u64 __user *)arg); | |
08247e31 | 5217 | |
cf4957f1 JO |
5218 | case PERF_EVENT_IOC_ID: |
5219 | { | |
5220 | u64 id = primary_event_id(event); | |
5221 | ||
5222 | if (copy_to_user((void __user *)arg, &id, sizeof(id))) | |
5223 | return -EFAULT; | |
5224 | return 0; | |
5225 | } | |
5226 | ||
cdd6c482 | 5227 | case PERF_EVENT_IOC_SET_OUTPUT: |
ac9721f3 | 5228 | { |
ac9721f3 | 5229 | int ret; |
ac9721f3 | 5230 | if (arg != -1) { |
2903ff01 AV |
5231 | struct perf_event *output_event; |
5232 | struct fd output; | |
5233 | ret = perf_fget_light(arg, &output); | |
5234 | if (ret) | |
5235 | return ret; | |
5236 | output_event = output.file->private_data; | |
5237 | ret = perf_event_set_output(event, output_event); | |
5238 | fdput(output); | |
5239 | } else { | |
5240 | ret = perf_event_set_output(event, NULL); | |
ac9721f3 | 5241 | } |
ac9721f3 PZ |
5242 | return ret; |
5243 | } | |
a4be7c27 | 5244 | |
6fb2915d LZ |
5245 | case PERF_EVENT_IOC_SET_FILTER: |
5246 | return perf_event_set_filter(event, (void __user *)arg); | |
5247 | ||
2541517c AS |
5248 | case PERF_EVENT_IOC_SET_BPF: |
5249 | return perf_event_set_bpf_prog(event, arg); | |
5250 | ||
86e7972f WN |
5251 | case PERF_EVENT_IOC_PAUSE_OUTPUT: { |
5252 | struct ring_buffer *rb; | |
5253 | ||
5254 | rcu_read_lock(); | |
5255 | rb = rcu_dereference(event->rb); | |
5256 | if (!rb || !rb->nr_pages) { | |
5257 | rcu_read_unlock(); | |
5258 | return -EINVAL; | |
5259 | } | |
5260 | rb_toggle_paused(rb, !!arg); | |
5261 | rcu_read_unlock(); | |
5262 | return 0; | |
5263 | } | |
f371b304 YS |
5264 | |
5265 | case PERF_EVENT_IOC_QUERY_BPF: | |
f4e2298e | 5266 | return perf_event_query_prog_array(event, (void __user *)arg); |
32ff77e8 MC |
5267 | |
5268 | case PERF_EVENT_IOC_MODIFY_ATTRIBUTES: { | |
5269 | struct perf_event_attr new_attr; | |
5270 | int err = perf_copy_attr((struct perf_event_attr __user *)arg, | |
5271 | &new_attr); | |
5272 | ||
5273 | if (err) | |
5274 | return err; | |
5275 | ||
5276 | return perf_event_modify_attr(event, &new_attr); | |
5277 | } | |
d859e29f | 5278 | default: |
3df5edad | 5279 | return -ENOTTY; |
d859e29f | 5280 | } |
3df5edad PZ |
5281 | |
5282 | if (flags & PERF_IOC_FLAG_GROUP) | |
cdd6c482 | 5283 | perf_event_for_each(event, func); |
3df5edad | 5284 | else |
cdd6c482 | 5285 | perf_event_for_each_child(event, func); |
3df5edad PZ |
5286 | |
5287 | return 0; | |
d859e29f PM |
5288 | } |
5289 | ||
f63a8daa PZ |
5290 | static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
5291 | { | |
5292 | struct perf_event *event = file->private_data; | |
5293 | struct perf_event_context *ctx; | |
5294 | long ret; | |
5295 | ||
da97e184 JFG |
5296 | /* Treat ioctl like writes as it is likely a mutating operation. */ |
5297 | ret = security_perf_event_write(event); | |
5298 | if (ret) | |
5299 | return ret; | |
5300 | ||
f63a8daa PZ |
5301 | ctx = perf_event_ctx_lock(event); |
5302 | ret = _perf_ioctl(event, cmd, arg); | |
5303 | perf_event_ctx_unlock(event, ctx); | |
5304 | ||
5305 | return ret; | |
5306 | } | |
5307 | ||
b3f20785 PM |
5308 | #ifdef CONFIG_COMPAT |
5309 | static long perf_compat_ioctl(struct file *file, unsigned int cmd, | |
5310 | unsigned long arg) | |
5311 | { | |
5312 | switch (_IOC_NR(cmd)) { | |
5313 | case _IOC_NR(PERF_EVENT_IOC_SET_FILTER): | |
5314 | case _IOC_NR(PERF_EVENT_IOC_ID): | |
82489c5f ES |
5315 | case _IOC_NR(PERF_EVENT_IOC_QUERY_BPF): |
5316 | case _IOC_NR(PERF_EVENT_IOC_MODIFY_ATTRIBUTES): | |
b3f20785 PM |
5317 | /* Fix up pointer size (usually 4 -> 8 in 32-on-64-bit case */ |
5318 | if (_IOC_SIZE(cmd) == sizeof(compat_uptr_t)) { | |
5319 | cmd &= ~IOCSIZE_MASK; | |
5320 | cmd |= sizeof(void *) << IOCSIZE_SHIFT; | |
5321 | } | |
5322 | break; | |
5323 | } | |
5324 | return perf_ioctl(file, cmd, arg); | |
5325 | } | |
5326 | #else | |
5327 | # define perf_compat_ioctl NULL | |
5328 | #endif | |
5329 | ||
cdd6c482 | 5330 | int perf_event_task_enable(void) |
771d7cde | 5331 | { |
f63a8daa | 5332 | struct perf_event_context *ctx; |
cdd6c482 | 5333 | struct perf_event *event; |
771d7cde | 5334 | |
cdd6c482 | 5335 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
5336 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
5337 | ctx = perf_event_ctx_lock(event); | |
5338 | perf_event_for_each_child(event, _perf_event_enable); | |
5339 | perf_event_ctx_unlock(event, ctx); | |
5340 | } | |
cdd6c482 | 5341 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
5342 | |
5343 | return 0; | |
5344 | } | |
5345 | ||
cdd6c482 | 5346 | int perf_event_task_disable(void) |
771d7cde | 5347 | { |
f63a8daa | 5348 | struct perf_event_context *ctx; |
cdd6c482 | 5349 | struct perf_event *event; |
771d7cde | 5350 | |
cdd6c482 | 5351 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
5352 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
5353 | ctx = perf_event_ctx_lock(event); | |
5354 | perf_event_for_each_child(event, _perf_event_disable); | |
5355 | perf_event_ctx_unlock(event, ctx); | |
5356 | } | |
cdd6c482 | 5357 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
5358 | |
5359 | return 0; | |
5360 | } | |
5361 | ||
cdd6c482 | 5362 | static int perf_event_index(struct perf_event *event) |
194002b2 | 5363 | { |
a4eaf7f1 PZ |
5364 | if (event->hw.state & PERF_HES_STOPPED) |
5365 | return 0; | |
5366 | ||
cdd6c482 | 5367 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
194002b2 PZ |
5368 | return 0; |
5369 | ||
35edc2a5 | 5370 | return event->pmu->event_idx(event); |
194002b2 PZ |
5371 | } |
5372 | ||
c4794295 | 5373 | static void calc_timer_values(struct perf_event *event, |
e3f3541c | 5374 | u64 *now, |
7f310a5d EM |
5375 | u64 *enabled, |
5376 | u64 *running) | |
c4794295 | 5377 | { |
e3f3541c | 5378 | u64 ctx_time; |
c4794295 | 5379 | |
e3f3541c PZ |
5380 | *now = perf_clock(); |
5381 | ctx_time = event->shadow_ctx_time + *now; | |
0d3d73aa | 5382 | __perf_update_times(event, ctx_time, enabled, running); |
c4794295 EM |
5383 | } |
5384 | ||
fa731587 PZ |
5385 | static void perf_event_init_userpage(struct perf_event *event) |
5386 | { | |
5387 | struct perf_event_mmap_page *userpg; | |
5388 | struct ring_buffer *rb; | |
5389 | ||
5390 | rcu_read_lock(); | |
5391 | rb = rcu_dereference(event->rb); | |
5392 | if (!rb) | |
5393 | goto unlock; | |
5394 | ||
5395 | userpg = rb->user_page; | |
5396 | ||
5397 | /* Allow new userspace to detect that bit 0 is deprecated */ | |
5398 | userpg->cap_bit0_is_deprecated = 1; | |
5399 | userpg->size = offsetof(struct perf_event_mmap_page, __reserved); | |
e8c6deac AS |
5400 | userpg->data_offset = PAGE_SIZE; |
5401 | userpg->data_size = perf_data_size(rb); | |
fa731587 PZ |
5402 | |
5403 | unlock: | |
5404 | rcu_read_unlock(); | |
5405 | } | |
5406 | ||
c1317ec2 AL |
5407 | void __weak arch_perf_update_userpage( |
5408 | struct perf_event *event, struct perf_event_mmap_page *userpg, u64 now) | |
e3f3541c PZ |
5409 | { |
5410 | } | |
5411 | ||
38ff667b PZ |
5412 | /* |
5413 | * Callers need to ensure there can be no nesting of this function, otherwise | |
5414 | * the seqlock logic goes bad. We can not serialize this because the arch | |
5415 | * code calls this from NMI context. | |
5416 | */ | |
cdd6c482 | 5417 | void perf_event_update_userpage(struct perf_event *event) |
37d81828 | 5418 | { |
cdd6c482 | 5419 | struct perf_event_mmap_page *userpg; |
76369139 | 5420 | struct ring_buffer *rb; |
e3f3541c | 5421 | u64 enabled, running, now; |
38ff667b PZ |
5422 | |
5423 | rcu_read_lock(); | |
5ec4c599 PZ |
5424 | rb = rcu_dereference(event->rb); |
5425 | if (!rb) | |
5426 | goto unlock; | |
5427 | ||
0d641208 EM |
5428 | /* |
5429 | * compute total_time_enabled, total_time_running | |
5430 | * based on snapshot values taken when the event | |
5431 | * was last scheduled in. | |
5432 | * | |
5433 | * we cannot simply called update_context_time() | |
5434 | * because of locking issue as we can be called in | |
5435 | * NMI context | |
5436 | */ | |
e3f3541c | 5437 | calc_timer_values(event, &now, &enabled, &running); |
38ff667b | 5438 | |
76369139 | 5439 | userpg = rb->user_page; |
7b732a75 | 5440 | /* |
9d2dcc8f MF |
5441 | * Disable preemption to guarantee consistent time stamps are stored to |
5442 | * the user page. | |
7b732a75 PZ |
5443 | */ |
5444 | preempt_disable(); | |
37d81828 | 5445 | ++userpg->lock; |
92f22a38 | 5446 | barrier(); |
cdd6c482 | 5447 | userpg->index = perf_event_index(event); |
b5e58793 | 5448 | userpg->offset = perf_event_count(event); |
365a4038 | 5449 | if (userpg->index) |
e7850595 | 5450 | userpg->offset -= local64_read(&event->hw.prev_count); |
7b732a75 | 5451 | |
0d641208 | 5452 | userpg->time_enabled = enabled + |
cdd6c482 | 5453 | atomic64_read(&event->child_total_time_enabled); |
7f8b4e4e | 5454 | |
0d641208 | 5455 | userpg->time_running = running + |
cdd6c482 | 5456 | atomic64_read(&event->child_total_time_running); |
7f8b4e4e | 5457 | |
c1317ec2 | 5458 | arch_perf_update_userpage(event, userpg, now); |
e3f3541c | 5459 | |
92f22a38 | 5460 | barrier(); |
37d81828 | 5461 | ++userpg->lock; |
7b732a75 | 5462 | preempt_enable(); |
38ff667b | 5463 | unlock: |
7b732a75 | 5464 | rcu_read_unlock(); |
37d81828 | 5465 | } |
82975c46 | 5466 | EXPORT_SYMBOL_GPL(perf_event_update_userpage); |
37d81828 | 5467 | |
9e3ed2d7 | 5468 | static vm_fault_t perf_mmap_fault(struct vm_fault *vmf) |
906010b2 | 5469 | { |
11bac800 | 5470 | struct perf_event *event = vmf->vma->vm_file->private_data; |
76369139 | 5471 | struct ring_buffer *rb; |
9e3ed2d7 | 5472 | vm_fault_t ret = VM_FAULT_SIGBUS; |
906010b2 PZ |
5473 | |
5474 | if (vmf->flags & FAULT_FLAG_MKWRITE) { | |
5475 | if (vmf->pgoff == 0) | |
5476 | ret = 0; | |
5477 | return ret; | |
5478 | } | |
5479 | ||
5480 | rcu_read_lock(); | |
76369139 FW |
5481 | rb = rcu_dereference(event->rb); |
5482 | if (!rb) | |
906010b2 PZ |
5483 | goto unlock; |
5484 | ||
5485 | if (vmf->pgoff && (vmf->flags & FAULT_FLAG_WRITE)) | |
5486 | goto unlock; | |
5487 | ||
76369139 | 5488 | vmf->page = perf_mmap_to_page(rb, vmf->pgoff); |
906010b2 PZ |
5489 | if (!vmf->page) |
5490 | goto unlock; | |
5491 | ||
5492 | get_page(vmf->page); | |
11bac800 | 5493 | vmf->page->mapping = vmf->vma->vm_file->f_mapping; |
906010b2 PZ |
5494 | vmf->page->index = vmf->pgoff; |
5495 | ||
5496 | ret = 0; | |
5497 | unlock: | |
5498 | rcu_read_unlock(); | |
5499 | ||
5500 | return ret; | |
5501 | } | |
5502 | ||
10c6db11 PZ |
5503 | static void ring_buffer_attach(struct perf_event *event, |
5504 | struct ring_buffer *rb) | |
5505 | { | |
b69cf536 | 5506 | struct ring_buffer *old_rb = NULL; |
10c6db11 PZ |
5507 | unsigned long flags; |
5508 | ||
b69cf536 PZ |
5509 | if (event->rb) { |
5510 | /* | |
5511 | * Should be impossible, we set this when removing | |
5512 | * event->rb_entry and wait/clear when adding event->rb_entry. | |
5513 | */ | |
5514 | WARN_ON_ONCE(event->rcu_pending); | |
10c6db11 | 5515 | |
b69cf536 | 5516 | old_rb = event->rb; |
b69cf536 PZ |
5517 | spin_lock_irqsave(&old_rb->event_lock, flags); |
5518 | list_del_rcu(&event->rb_entry); | |
5519 | spin_unlock_irqrestore(&old_rb->event_lock, flags); | |
10c6db11 | 5520 | |
2f993cf0 ON |
5521 | event->rcu_batches = get_state_synchronize_rcu(); |
5522 | event->rcu_pending = 1; | |
b69cf536 | 5523 | } |
10c6db11 | 5524 | |
b69cf536 | 5525 | if (rb) { |
2f993cf0 ON |
5526 | if (event->rcu_pending) { |
5527 | cond_synchronize_rcu(event->rcu_batches); | |
5528 | event->rcu_pending = 0; | |
5529 | } | |
5530 | ||
b69cf536 PZ |
5531 | spin_lock_irqsave(&rb->event_lock, flags); |
5532 | list_add_rcu(&event->rb_entry, &rb->event_list); | |
5533 | spin_unlock_irqrestore(&rb->event_lock, flags); | |
5534 | } | |
5535 | ||
767ae086 AS |
5536 | /* |
5537 | * Avoid racing with perf_mmap_close(AUX): stop the event | |
5538 | * before swizzling the event::rb pointer; if it's getting | |
5539 | * unmapped, its aux_mmap_count will be 0 and it won't | |
5540 | * restart. See the comment in __perf_pmu_output_stop(). | |
5541 | * | |
5542 | * Data will inevitably be lost when set_output is done in | |
5543 | * mid-air, but then again, whoever does it like this is | |
5544 | * not in for the data anyway. | |
5545 | */ | |
5546 | if (has_aux(event)) | |
5547 | perf_event_stop(event, 0); | |
5548 | ||
b69cf536 PZ |
5549 | rcu_assign_pointer(event->rb, rb); |
5550 | ||
5551 | if (old_rb) { | |
5552 | ring_buffer_put(old_rb); | |
5553 | /* | |
5554 | * Since we detached before setting the new rb, so that we | |
5555 | * could attach the new rb, we could have missed a wakeup. | |
5556 | * Provide it now. | |
5557 | */ | |
5558 | wake_up_all(&event->waitq); | |
5559 | } | |
10c6db11 PZ |
5560 | } |
5561 | ||
5562 | static void ring_buffer_wakeup(struct perf_event *event) | |
5563 | { | |
5564 | struct ring_buffer *rb; | |
5565 | ||
5566 | rcu_read_lock(); | |
5567 | rb = rcu_dereference(event->rb); | |
9bb5d40c PZ |
5568 | if (rb) { |
5569 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) | |
5570 | wake_up_all(&event->waitq); | |
5571 | } | |
10c6db11 PZ |
5572 | rcu_read_unlock(); |
5573 | } | |
5574 | ||
fdc26706 | 5575 | struct ring_buffer *ring_buffer_get(struct perf_event *event) |
7b732a75 | 5576 | { |
76369139 | 5577 | struct ring_buffer *rb; |
7b732a75 | 5578 | |
ac9721f3 | 5579 | rcu_read_lock(); |
76369139 FW |
5580 | rb = rcu_dereference(event->rb); |
5581 | if (rb) { | |
fecb8ed2 | 5582 | if (!refcount_inc_not_zero(&rb->refcount)) |
76369139 | 5583 | rb = NULL; |
ac9721f3 PZ |
5584 | } |
5585 | rcu_read_unlock(); | |
5586 | ||
76369139 | 5587 | return rb; |
ac9721f3 PZ |
5588 | } |
5589 | ||
fdc26706 | 5590 | void ring_buffer_put(struct ring_buffer *rb) |
ac9721f3 | 5591 | { |
fecb8ed2 | 5592 | if (!refcount_dec_and_test(&rb->refcount)) |
ac9721f3 | 5593 | return; |
7b732a75 | 5594 | |
9bb5d40c | 5595 | WARN_ON_ONCE(!list_empty(&rb->event_list)); |
10c6db11 | 5596 | |
76369139 | 5597 | call_rcu(&rb->rcu_head, rb_free_rcu); |
7b732a75 PZ |
5598 | } |
5599 | ||
5600 | static void perf_mmap_open(struct vm_area_struct *vma) | |
5601 | { | |
cdd6c482 | 5602 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 5603 | |
cdd6c482 | 5604 | atomic_inc(&event->mmap_count); |
9bb5d40c | 5605 | atomic_inc(&event->rb->mmap_count); |
1e0fb9ec | 5606 | |
45bfb2e5 PZ |
5607 | if (vma->vm_pgoff) |
5608 | atomic_inc(&event->rb->aux_mmap_count); | |
5609 | ||
1e0fb9ec | 5610 | if (event->pmu->event_mapped) |
bfe33492 | 5611 | event->pmu->event_mapped(event, vma->vm_mm); |
7b732a75 PZ |
5612 | } |
5613 | ||
95ff4ca2 AS |
5614 | static void perf_pmu_output_stop(struct perf_event *event); |
5615 | ||
9bb5d40c PZ |
5616 | /* |
5617 | * A buffer can be mmap()ed multiple times; either directly through the same | |
5618 | * event, or through other events by use of perf_event_set_output(). | |
5619 | * | |
5620 | * In order to undo the VM accounting done by perf_mmap() we need to destroy | |
5621 | * the buffer here, where we still have a VM context. This means we need | |
5622 | * to detach all events redirecting to us. | |
5623 | */ | |
7b732a75 PZ |
5624 | static void perf_mmap_close(struct vm_area_struct *vma) |
5625 | { | |
cdd6c482 | 5626 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 5627 | |
b69cf536 | 5628 | struct ring_buffer *rb = ring_buffer_get(event); |
9bb5d40c PZ |
5629 | struct user_struct *mmap_user = rb->mmap_user; |
5630 | int mmap_locked = rb->mmap_locked; | |
5631 | unsigned long size = perf_data_size(rb); | |
789f90fc | 5632 | |
1e0fb9ec | 5633 | if (event->pmu->event_unmapped) |
bfe33492 | 5634 | event->pmu->event_unmapped(event, vma->vm_mm); |
1e0fb9ec | 5635 | |
45bfb2e5 PZ |
5636 | /* |
5637 | * rb->aux_mmap_count will always drop before rb->mmap_count and | |
5638 | * event->mmap_count, so it is ok to use event->mmap_mutex to | |
5639 | * serialize with perf_mmap here. | |
5640 | */ | |
5641 | if (rb_has_aux(rb) && vma->vm_pgoff == rb->aux_pgoff && | |
5642 | atomic_dec_and_mutex_lock(&rb->aux_mmap_count, &event->mmap_mutex)) { | |
95ff4ca2 AS |
5643 | /* |
5644 | * Stop all AUX events that are writing to this buffer, | |
5645 | * so that we can free its AUX pages and corresponding PMU | |
5646 | * data. Note that after rb::aux_mmap_count dropped to zero, | |
5647 | * they won't start any more (see perf_aux_output_begin()). | |
5648 | */ | |
5649 | perf_pmu_output_stop(event); | |
5650 | ||
5651 | /* now it's safe to free the pages */ | |
5e6c3c7b TR |
5652 | if (!rb->aux_mmap_locked) |
5653 | atomic_long_sub(rb->aux_nr_pages, &mmap_user->locked_vm); | |
5654 | else | |
5655 | atomic64_sub(rb->aux_mmap_locked, &vma->vm_mm->pinned_vm); | |
45bfb2e5 | 5656 | |
95ff4ca2 | 5657 | /* this has to be the last one */ |
45bfb2e5 | 5658 | rb_free_aux(rb); |
ca3bb3d0 | 5659 | WARN_ON_ONCE(refcount_read(&rb->aux_refcount)); |
95ff4ca2 | 5660 | |
45bfb2e5 PZ |
5661 | mutex_unlock(&event->mmap_mutex); |
5662 | } | |
5663 | ||
9bb5d40c PZ |
5664 | atomic_dec(&rb->mmap_count); |
5665 | ||
5666 | if (!atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex)) | |
b69cf536 | 5667 | goto out_put; |
9bb5d40c | 5668 | |
b69cf536 | 5669 | ring_buffer_attach(event, NULL); |
9bb5d40c PZ |
5670 | mutex_unlock(&event->mmap_mutex); |
5671 | ||
5672 | /* If there's still other mmap()s of this buffer, we're done. */ | |
b69cf536 PZ |
5673 | if (atomic_read(&rb->mmap_count)) |
5674 | goto out_put; | |
ac9721f3 | 5675 | |
9bb5d40c PZ |
5676 | /* |
5677 | * No other mmap()s, detach from all other events that might redirect | |
5678 | * into the now unreachable buffer. Somewhat complicated by the | |
5679 | * fact that rb::event_lock otherwise nests inside mmap_mutex. | |
5680 | */ | |
5681 | again: | |
5682 | rcu_read_lock(); | |
5683 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) { | |
5684 | if (!atomic_long_inc_not_zero(&event->refcount)) { | |
5685 | /* | |
5686 | * This event is en-route to free_event() which will | |
5687 | * detach it and remove it from the list. | |
5688 | */ | |
5689 | continue; | |
5690 | } | |
5691 | rcu_read_unlock(); | |
789f90fc | 5692 | |
9bb5d40c PZ |
5693 | mutex_lock(&event->mmap_mutex); |
5694 | /* | |
5695 | * Check we didn't race with perf_event_set_output() which can | |
5696 | * swizzle the rb from under us while we were waiting to | |
5697 | * acquire mmap_mutex. | |
5698 | * | |
5699 | * If we find a different rb; ignore this event, a next | |
5700 | * iteration will no longer find it on the list. We have to | |
5701 | * still restart the iteration to make sure we're not now | |
5702 | * iterating the wrong list. | |
5703 | */ | |
b69cf536 PZ |
5704 | if (event->rb == rb) |
5705 | ring_buffer_attach(event, NULL); | |
5706 | ||
cdd6c482 | 5707 | mutex_unlock(&event->mmap_mutex); |
9bb5d40c | 5708 | put_event(event); |
ac9721f3 | 5709 | |
9bb5d40c PZ |
5710 | /* |
5711 | * Restart the iteration; either we're on the wrong list or | |
5712 | * destroyed its integrity by doing a deletion. | |
5713 | */ | |
5714 | goto again; | |
7b732a75 | 5715 | } |
9bb5d40c PZ |
5716 | rcu_read_unlock(); |
5717 | ||
5718 | /* | |
5719 | * It could be there's still a few 0-ref events on the list; they'll | |
5720 | * get cleaned up by free_event() -- they'll also still have their | |
5721 | * ref on the rb and will free it whenever they are done with it. | |
5722 | * | |
5723 | * Aside from that, this buffer is 'fully' detached and unmapped, | |
5724 | * undo the VM accounting. | |
5725 | */ | |
5726 | ||
d44248a4 SL |
5727 | atomic_long_sub((size >> PAGE_SHIFT) + 1 - mmap_locked, |
5728 | &mmap_user->locked_vm); | |
70f8a3ca | 5729 | atomic64_sub(mmap_locked, &vma->vm_mm->pinned_vm); |
9bb5d40c PZ |
5730 | free_uid(mmap_user); |
5731 | ||
b69cf536 | 5732 | out_put: |
9bb5d40c | 5733 | ring_buffer_put(rb); /* could be last */ |
37d81828 PM |
5734 | } |
5735 | ||
f0f37e2f | 5736 | static const struct vm_operations_struct perf_mmap_vmops = { |
43a21ea8 | 5737 | .open = perf_mmap_open, |
fca0c116 | 5738 | .close = perf_mmap_close, /* non mergeable */ |
43a21ea8 PZ |
5739 | .fault = perf_mmap_fault, |
5740 | .page_mkwrite = perf_mmap_fault, | |
37d81828 PM |
5741 | }; |
5742 | ||
5743 | static int perf_mmap(struct file *file, struct vm_area_struct *vma) | |
5744 | { | |
cdd6c482 | 5745 | struct perf_event *event = file->private_data; |
22a4f650 | 5746 | unsigned long user_locked, user_lock_limit; |
789f90fc | 5747 | struct user_struct *user = current_user(); |
22a4f650 | 5748 | unsigned long locked, lock_limit; |
45bfb2e5 | 5749 | struct ring_buffer *rb = NULL; |
7b732a75 PZ |
5750 | unsigned long vma_size; |
5751 | unsigned long nr_pages; | |
45bfb2e5 | 5752 | long user_extra = 0, extra = 0; |
d57e34fd | 5753 | int ret = 0, flags = 0; |
37d81828 | 5754 | |
c7920614 PZ |
5755 | /* |
5756 | * Don't allow mmap() of inherited per-task counters. This would | |
5757 | * create a performance issue due to all children writing to the | |
76369139 | 5758 | * same rb. |
c7920614 PZ |
5759 | */ |
5760 | if (event->cpu == -1 && event->attr.inherit) | |
5761 | return -EINVAL; | |
5762 | ||
43a21ea8 | 5763 | if (!(vma->vm_flags & VM_SHARED)) |
37d81828 | 5764 | return -EINVAL; |
7b732a75 | 5765 | |
da97e184 JFG |
5766 | ret = security_perf_event_read(event); |
5767 | if (ret) | |
5768 | return ret; | |
5769 | ||
7b732a75 | 5770 | vma_size = vma->vm_end - vma->vm_start; |
45bfb2e5 PZ |
5771 | |
5772 | if (vma->vm_pgoff == 0) { | |
5773 | nr_pages = (vma_size / PAGE_SIZE) - 1; | |
5774 | } else { | |
5775 | /* | |
5776 | * AUX area mapping: if rb->aux_nr_pages != 0, it's already | |
5777 | * mapped, all subsequent mappings should have the same size | |
5778 | * and offset. Must be above the normal perf buffer. | |
5779 | */ | |
5780 | u64 aux_offset, aux_size; | |
5781 | ||
5782 | if (!event->rb) | |
5783 | return -EINVAL; | |
5784 | ||
5785 | nr_pages = vma_size / PAGE_SIZE; | |
5786 | ||
5787 | mutex_lock(&event->mmap_mutex); | |
5788 | ret = -EINVAL; | |
5789 | ||
5790 | rb = event->rb; | |
5791 | if (!rb) | |
5792 | goto aux_unlock; | |
5793 | ||
6aa7de05 MR |
5794 | aux_offset = READ_ONCE(rb->user_page->aux_offset); |
5795 | aux_size = READ_ONCE(rb->user_page->aux_size); | |
45bfb2e5 PZ |
5796 | |
5797 | if (aux_offset < perf_data_size(rb) + PAGE_SIZE) | |
5798 | goto aux_unlock; | |
5799 | ||
5800 | if (aux_offset != vma->vm_pgoff << PAGE_SHIFT) | |
5801 | goto aux_unlock; | |
5802 | ||
5803 | /* already mapped with a different offset */ | |
5804 | if (rb_has_aux(rb) && rb->aux_pgoff != vma->vm_pgoff) | |
5805 | goto aux_unlock; | |
5806 | ||
5807 | if (aux_size != vma_size || aux_size != nr_pages * PAGE_SIZE) | |
5808 | goto aux_unlock; | |
5809 | ||
5810 | /* already mapped with a different size */ | |
5811 | if (rb_has_aux(rb) && rb->aux_nr_pages != nr_pages) | |
5812 | goto aux_unlock; | |
5813 | ||
5814 | if (!is_power_of_2(nr_pages)) | |
5815 | goto aux_unlock; | |
5816 | ||
5817 | if (!atomic_inc_not_zero(&rb->mmap_count)) | |
5818 | goto aux_unlock; | |
5819 | ||
5820 | if (rb_has_aux(rb)) { | |
5821 | atomic_inc(&rb->aux_mmap_count); | |
5822 | ret = 0; | |
5823 | goto unlock; | |
5824 | } | |
5825 | ||
5826 | atomic_set(&rb->aux_mmap_count, 1); | |
5827 | user_extra = nr_pages; | |
5828 | ||
5829 | goto accounting; | |
5830 | } | |
7b732a75 | 5831 | |
7730d865 | 5832 | /* |
76369139 | 5833 | * If we have rb pages ensure they're a power-of-two number, so we |
7730d865 PZ |
5834 | * can do bitmasks instead of modulo. |
5835 | */ | |
2ed11312 | 5836 | if (nr_pages != 0 && !is_power_of_2(nr_pages)) |
37d81828 PM |
5837 | return -EINVAL; |
5838 | ||
7b732a75 | 5839 | if (vma_size != PAGE_SIZE * (1 + nr_pages)) |
37d81828 PM |
5840 | return -EINVAL; |
5841 | ||
cdd6c482 | 5842 | WARN_ON_ONCE(event->ctx->parent_ctx); |
9bb5d40c | 5843 | again: |
cdd6c482 | 5844 | mutex_lock(&event->mmap_mutex); |
76369139 | 5845 | if (event->rb) { |
9bb5d40c | 5846 | if (event->rb->nr_pages != nr_pages) { |
ebb3c4c4 | 5847 | ret = -EINVAL; |
9bb5d40c PZ |
5848 | goto unlock; |
5849 | } | |
5850 | ||
5851 | if (!atomic_inc_not_zero(&event->rb->mmap_count)) { | |
5852 | /* | |
5853 | * Raced against perf_mmap_close() through | |
5854 | * perf_event_set_output(). Try again, hope for better | |
5855 | * luck. | |
5856 | */ | |
5857 | mutex_unlock(&event->mmap_mutex); | |
5858 | goto again; | |
5859 | } | |
5860 | ||
ebb3c4c4 PZ |
5861 | goto unlock; |
5862 | } | |
5863 | ||
789f90fc | 5864 | user_extra = nr_pages + 1; |
45bfb2e5 PZ |
5865 | |
5866 | accounting: | |
cdd6c482 | 5867 | user_lock_limit = sysctl_perf_event_mlock >> (PAGE_SHIFT - 10); |
a3862d3f IM |
5868 | |
5869 | /* | |
5870 | * Increase the limit linearly with more CPUs: | |
5871 | */ | |
5872 | user_lock_limit *= num_online_cpus(); | |
5873 | ||
789f90fc | 5874 | user_locked = atomic_long_read(&user->locked_vm) + user_extra; |
c5078f78 | 5875 | |
d44248a4 SL |
5876 | if (user_locked <= user_lock_limit) { |
5877 | /* charge all to locked_vm */ | |
5878 | } else if (atomic_long_read(&user->locked_vm) >= user_lock_limit) { | |
5879 | /* charge all to pinned_vm */ | |
5880 | extra = user_extra; | |
5881 | user_extra = 0; | |
5882 | } else { | |
5883 | /* | |
5884 | * charge locked_vm until it hits user_lock_limit; | |
5885 | * charge the rest from pinned_vm | |
5886 | */ | |
789f90fc | 5887 | extra = user_locked - user_lock_limit; |
d44248a4 SL |
5888 | user_extra -= extra; |
5889 | } | |
7b732a75 | 5890 | |
78d7d407 | 5891 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
7b732a75 | 5892 | lock_limit >>= PAGE_SHIFT; |
70f8a3ca | 5893 | locked = atomic64_read(&vma->vm_mm->pinned_vm) + extra; |
7b732a75 | 5894 | |
da97e184 | 5895 | if ((locked > lock_limit) && perf_is_paranoid() && |
459ec28a | 5896 | !capable(CAP_IPC_LOCK)) { |
ebb3c4c4 PZ |
5897 | ret = -EPERM; |
5898 | goto unlock; | |
5899 | } | |
7b732a75 | 5900 | |
45bfb2e5 | 5901 | WARN_ON(!rb && event->rb); |
906010b2 | 5902 | |
d57e34fd | 5903 | if (vma->vm_flags & VM_WRITE) |
76369139 | 5904 | flags |= RING_BUFFER_WRITABLE; |
d57e34fd | 5905 | |
76369139 | 5906 | if (!rb) { |
45bfb2e5 PZ |
5907 | rb = rb_alloc(nr_pages, |
5908 | event->attr.watermark ? event->attr.wakeup_watermark : 0, | |
5909 | event->cpu, flags); | |
26cb63ad | 5910 | |
45bfb2e5 PZ |
5911 | if (!rb) { |
5912 | ret = -ENOMEM; | |
5913 | goto unlock; | |
5914 | } | |
43a21ea8 | 5915 | |
45bfb2e5 PZ |
5916 | atomic_set(&rb->mmap_count, 1); |
5917 | rb->mmap_user = get_current_user(); | |
5918 | rb->mmap_locked = extra; | |
26cb63ad | 5919 | |
45bfb2e5 | 5920 | ring_buffer_attach(event, rb); |
ac9721f3 | 5921 | |
45bfb2e5 PZ |
5922 | perf_event_init_userpage(event); |
5923 | perf_event_update_userpage(event); | |
5924 | } else { | |
1a594131 AS |
5925 | ret = rb_alloc_aux(rb, event, vma->vm_pgoff, nr_pages, |
5926 | event->attr.aux_watermark, flags); | |
45bfb2e5 PZ |
5927 | if (!ret) |
5928 | rb->aux_mmap_locked = extra; | |
5929 | } | |
9a0f05cb | 5930 | |
ebb3c4c4 | 5931 | unlock: |
45bfb2e5 PZ |
5932 | if (!ret) { |
5933 | atomic_long_add(user_extra, &user->locked_vm); | |
70f8a3ca | 5934 | atomic64_add(extra, &vma->vm_mm->pinned_vm); |
45bfb2e5 | 5935 | |
ac9721f3 | 5936 | atomic_inc(&event->mmap_count); |
45bfb2e5 PZ |
5937 | } else if (rb) { |
5938 | atomic_dec(&rb->mmap_count); | |
5939 | } | |
5940 | aux_unlock: | |
cdd6c482 | 5941 | mutex_unlock(&event->mmap_mutex); |
37d81828 | 5942 | |
9bb5d40c PZ |
5943 | /* |
5944 | * Since pinned accounting is per vm we cannot allow fork() to copy our | |
5945 | * vma. | |
5946 | */ | |
26cb63ad | 5947 | vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND | VM_DONTDUMP; |
37d81828 | 5948 | vma->vm_ops = &perf_mmap_vmops; |
7b732a75 | 5949 | |
1e0fb9ec | 5950 | if (event->pmu->event_mapped) |
bfe33492 | 5951 | event->pmu->event_mapped(event, vma->vm_mm); |
1e0fb9ec | 5952 | |
7b732a75 | 5953 | return ret; |
37d81828 PM |
5954 | } |
5955 | ||
3c446b3d PZ |
5956 | static int perf_fasync(int fd, struct file *filp, int on) |
5957 | { | |
496ad9aa | 5958 | struct inode *inode = file_inode(filp); |
cdd6c482 | 5959 | struct perf_event *event = filp->private_data; |
3c446b3d PZ |
5960 | int retval; |
5961 | ||
5955102c | 5962 | inode_lock(inode); |
cdd6c482 | 5963 | retval = fasync_helper(fd, filp, on, &event->fasync); |
5955102c | 5964 | inode_unlock(inode); |
3c446b3d PZ |
5965 | |
5966 | if (retval < 0) | |
5967 | return retval; | |
5968 | ||
5969 | return 0; | |
5970 | } | |
5971 | ||
0793a61d | 5972 | static const struct file_operations perf_fops = { |
3326c1ce | 5973 | .llseek = no_llseek, |
0793a61d TG |
5974 | .release = perf_release, |
5975 | .read = perf_read, | |
5976 | .poll = perf_poll, | |
d859e29f | 5977 | .unlocked_ioctl = perf_ioctl, |
b3f20785 | 5978 | .compat_ioctl = perf_compat_ioctl, |
37d81828 | 5979 | .mmap = perf_mmap, |
3c446b3d | 5980 | .fasync = perf_fasync, |
0793a61d TG |
5981 | }; |
5982 | ||
925d519a | 5983 | /* |
cdd6c482 | 5984 | * Perf event wakeup |
925d519a PZ |
5985 | * |
5986 | * If there's data, ensure we set the poll() state and publish everything | |
5987 | * to user-space before waking everybody up. | |
5988 | */ | |
5989 | ||
fed66e2c PZ |
5990 | static inline struct fasync_struct **perf_event_fasync(struct perf_event *event) |
5991 | { | |
5992 | /* only the parent has fasync state */ | |
5993 | if (event->parent) | |
5994 | event = event->parent; | |
5995 | return &event->fasync; | |
5996 | } | |
5997 | ||
cdd6c482 | 5998 | void perf_event_wakeup(struct perf_event *event) |
925d519a | 5999 | { |
10c6db11 | 6000 | ring_buffer_wakeup(event); |
4c9e2542 | 6001 | |
cdd6c482 | 6002 | if (event->pending_kill) { |
fed66e2c | 6003 | kill_fasync(perf_event_fasync(event), SIGIO, event->pending_kill); |
cdd6c482 | 6004 | event->pending_kill = 0; |
4c9e2542 | 6005 | } |
925d519a PZ |
6006 | } |
6007 | ||
1d54ad94 PZ |
6008 | static void perf_pending_event_disable(struct perf_event *event) |
6009 | { | |
6010 | int cpu = READ_ONCE(event->pending_disable); | |
6011 | ||
6012 | if (cpu < 0) | |
6013 | return; | |
6014 | ||
6015 | if (cpu == smp_processor_id()) { | |
6016 | WRITE_ONCE(event->pending_disable, -1); | |
6017 | perf_event_disable_local(event); | |
6018 | return; | |
6019 | } | |
6020 | ||
6021 | /* | |
6022 | * CPU-A CPU-B | |
6023 | * | |
6024 | * perf_event_disable_inatomic() | |
6025 | * @pending_disable = CPU-A; | |
6026 | * irq_work_queue(); | |
6027 | * | |
6028 | * sched-out | |
6029 | * @pending_disable = -1; | |
6030 | * | |
6031 | * sched-in | |
6032 | * perf_event_disable_inatomic() | |
6033 | * @pending_disable = CPU-B; | |
6034 | * irq_work_queue(); // FAILS | |
6035 | * | |
6036 | * irq_work_run() | |
6037 | * perf_pending_event() | |
6038 | * | |
6039 | * But the event runs on CPU-B and wants disabling there. | |
6040 | */ | |
6041 | irq_work_queue_on(&event->pending, cpu); | |
6042 | } | |
6043 | ||
e360adbe | 6044 | static void perf_pending_event(struct irq_work *entry) |
79f14641 | 6045 | { |
1d54ad94 | 6046 | struct perf_event *event = container_of(entry, struct perf_event, pending); |
d525211f PZ |
6047 | int rctx; |
6048 | ||
6049 | rctx = perf_swevent_get_recursion_context(); | |
6050 | /* | |
6051 | * If we 'fail' here, that's OK, it means recursion is already disabled | |
6052 | * and we won't recurse 'further'. | |
6053 | */ | |
79f14641 | 6054 | |
1d54ad94 | 6055 | perf_pending_event_disable(event); |
79f14641 | 6056 | |
cdd6c482 IM |
6057 | if (event->pending_wakeup) { |
6058 | event->pending_wakeup = 0; | |
6059 | perf_event_wakeup(event); | |
79f14641 | 6060 | } |
d525211f PZ |
6061 | |
6062 | if (rctx >= 0) | |
6063 | perf_swevent_put_recursion_context(rctx); | |
79f14641 PZ |
6064 | } |
6065 | ||
39447b38 ZY |
6066 | /* |
6067 | * We assume there is only KVM supporting the callbacks. | |
6068 | * Later on, we might change it to a list if there is | |
6069 | * another virtualization implementation supporting the callbacks. | |
6070 | */ | |
6071 | struct perf_guest_info_callbacks *perf_guest_cbs; | |
6072 | ||
6073 | int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
6074 | { | |
6075 | perf_guest_cbs = cbs; | |
6076 | return 0; | |
6077 | } | |
6078 | EXPORT_SYMBOL_GPL(perf_register_guest_info_callbacks); | |
6079 | ||
6080 | int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
6081 | { | |
6082 | perf_guest_cbs = NULL; | |
6083 | return 0; | |
6084 | } | |
6085 | EXPORT_SYMBOL_GPL(perf_unregister_guest_info_callbacks); | |
6086 | ||
4018994f JO |
6087 | static void |
6088 | perf_output_sample_regs(struct perf_output_handle *handle, | |
6089 | struct pt_regs *regs, u64 mask) | |
6090 | { | |
6091 | int bit; | |
29dd3288 | 6092 | DECLARE_BITMAP(_mask, 64); |
4018994f | 6093 | |
29dd3288 MS |
6094 | bitmap_from_u64(_mask, mask); |
6095 | for_each_set_bit(bit, _mask, sizeof(mask) * BITS_PER_BYTE) { | |
4018994f JO |
6096 | u64 val; |
6097 | ||
6098 | val = perf_reg_value(regs, bit); | |
6099 | perf_output_put(handle, val); | |
6100 | } | |
6101 | } | |
6102 | ||
60e2364e | 6103 | static void perf_sample_regs_user(struct perf_regs *regs_user, |
88a7c26a AL |
6104 | struct pt_regs *regs, |
6105 | struct pt_regs *regs_user_copy) | |
4018994f | 6106 | { |
88a7c26a AL |
6107 | if (user_mode(regs)) { |
6108 | regs_user->abi = perf_reg_abi(current); | |
2565711f | 6109 | regs_user->regs = regs; |
085ebfe9 | 6110 | } else if (!(current->flags & PF_KTHREAD)) { |
88a7c26a | 6111 | perf_get_regs_user(regs_user, regs, regs_user_copy); |
2565711f PZ |
6112 | } else { |
6113 | regs_user->abi = PERF_SAMPLE_REGS_ABI_NONE; | |
6114 | regs_user->regs = NULL; | |
4018994f JO |
6115 | } |
6116 | } | |
6117 | ||
60e2364e SE |
6118 | static void perf_sample_regs_intr(struct perf_regs *regs_intr, |
6119 | struct pt_regs *regs) | |
6120 | { | |
6121 | regs_intr->regs = regs; | |
6122 | regs_intr->abi = perf_reg_abi(current); | |
6123 | } | |
6124 | ||
6125 | ||
c5ebcedb JO |
6126 | /* |
6127 | * Get remaining task size from user stack pointer. | |
6128 | * | |
6129 | * It'd be better to take stack vma map and limit this more | |
9f014e3a | 6130 | * precisely, but there's no way to get it safely under interrupt, |
c5ebcedb JO |
6131 | * so using TASK_SIZE as limit. |
6132 | */ | |
6133 | static u64 perf_ustack_task_size(struct pt_regs *regs) | |
6134 | { | |
6135 | unsigned long addr = perf_user_stack_pointer(regs); | |
6136 | ||
6137 | if (!addr || addr >= TASK_SIZE) | |
6138 | return 0; | |
6139 | ||
6140 | return TASK_SIZE - addr; | |
6141 | } | |
6142 | ||
6143 | static u16 | |
6144 | perf_sample_ustack_size(u16 stack_size, u16 header_size, | |
6145 | struct pt_regs *regs) | |
6146 | { | |
6147 | u64 task_size; | |
6148 | ||
6149 | /* No regs, no stack pointer, no dump. */ | |
6150 | if (!regs) | |
6151 | return 0; | |
6152 | ||
6153 | /* | |
6154 | * Check if we fit in with the requested stack size into the: | |
6155 | * - TASK_SIZE | |
6156 | * If we don't, we limit the size to the TASK_SIZE. | |
6157 | * | |
6158 | * - remaining sample size | |
6159 | * If we don't, we customize the stack size to | |
6160 | * fit in to the remaining sample size. | |
6161 | */ | |
6162 | ||
6163 | task_size = min((u64) USHRT_MAX, perf_ustack_task_size(regs)); | |
6164 | stack_size = min(stack_size, (u16) task_size); | |
6165 | ||
6166 | /* Current header size plus static size and dynamic size. */ | |
6167 | header_size += 2 * sizeof(u64); | |
6168 | ||
6169 | /* Do we fit in with the current stack dump size? */ | |
6170 | if ((u16) (header_size + stack_size) < header_size) { | |
6171 | /* | |
6172 | * If we overflow the maximum size for the sample, | |
6173 | * we customize the stack dump size to fit in. | |
6174 | */ | |
6175 | stack_size = USHRT_MAX - header_size - sizeof(u64); | |
6176 | stack_size = round_up(stack_size, sizeof(u64)); | |
6177 | } | |
6178 | ||
6179 | return stack_size; | |
6180 | } | |
6181 | ||
6182 | static void | |
6183 | perf_output_sample_ustack(struct perf_output_handle *handle, u64 dump_size, | |
6184 | struct pt_regs *regs) | |
6185 | { | |
6186 | /* Case of a kernel thread, nothing to dump */ | |
6187 | if (!regs) { | |
6188 | u64 size = 0; | |
6189 | perf_output_put(handle, size); | |
6190 | } else { | |
6191 | unsigned long sp; | |
6192 | unsigned int rem; | |
6193 | u64 dyn_size; | |
02e18447 | 6194 | mm_segment_t fs; |
c5ebcedb JO |
6195 | |
6196 | /* | |
6197 | * We dump: | |
6198 | * static size | |
6199 | * - the size requested by user or the best one we can fit | |
6200 | * in to the sample max size | |
6201 | * data | |
6202 | * - user stack dump data | |
6203 | * dynamic size | |
6204 | * - the actual dumped size | |
6205 | */ | |
6206 | ||
6207 | /* Static size. */ | |
6208 | perf_output_put(handle, dump_size); | |
6209 | ||
6210 | /* Data. */ | |
6211 | sp = perf_user_stack_pointer(regs); | |
02e18447 YC |
6212 | fs = get_fs(); |
6213 | set_fs(USER_DS); | |
c5ebcedb | 6214 | rem = __output_copy_user(handle, (void *) sp, dump_size); |
02e18447 | 6215 | set_fs(fs); |
c5ebcedb JO |
6216 | dyn_size = dump_size - rem; |
6217 | ||
6218 | perf_output_skip(handle, rem); | |
6219 | ||
6220 | /* Dynamic size. */ | |
6221 | perf_output_put(handle, dyn_size); | |
6222 | } | |
6223 | } | |
6224 | ||
c980d109 ACM |
6225 | static void __perf_event_header__init_id(struct perf_event_header *header, |
6226 | struct perf_sample_data *data, | |
6227 | struct perf_event *event) | |
6844c09d ACM |
6228 | { |
6229 | u64 sample_type = event->attr.sample_type; | |
6230 | ||
6231 | data->type = sample_type; | |
6232 | header->size += event->id_header_size; | |
6233 | ||
6234 | if (sample_type & PERF_SAMPLE_TID) { | |
6235 | /* namespace issues */ | |
6236 | data->tid_entry.pid = perf_event_pid(event, current); | |
6237 | data->tid_entry.tid = perf_event_tid(event, current); | |
6238 | } | |
6239 | ||
6240 | if (sample_type & PERF_SAMPLE_TIME) | |
34f43927 | 6241 | data->time = perf_event_clock(event); |
6844c09d | 6242 | |
ff3d527c | 6243 | if (sample_type & (PERF_SAMPLE_ID | PERF_SAMPLE_IDENTIFIER)) |
6844c09d ACM |
6244 | data->id = primary_event_id(event); |
6245 | ||
6246 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6247 | data->stream_id = event->id; | |
6248 | ||
6249 | if (sample_type & PERF_SAMPLE_CPU) { | |
6250 | data->cpu_entry.cpu = raw_smp_processor_id(); | |
6251 | data->cpu_entry.reserved = 0; | |
6252 | } | |
6253 | } | |
6254 | ||
76369139 FW |
6255 | void perf_event_header__init_id(struct perf_event_header *header, |
6256 | struct perf_sample_data *data, | |
6257 | struct perf_event *event) | |
c980d109 ACM |
6258 | { |
6259 | if (event->attr.sample_id_all) | |
6260 | __perf_event_header__init_id(header, data, event); | |
6261 | } | |
6262 | ||
6263 | static void __perf_event__output_id_sample(struct perf_output_handle *handle, | |
6264 | struct perf_sample_data *data) | |
6265 | { | |
6266 | u64 sample_type = data->type; | |
6267 | ||
6268 | if (sample_type & PERF_SAMPLE_TID) | |
6269 | perf_output_put(handle, data->tid_entry); | |
6270 | ||
6271 | if (sample_type & PERF_SAMPLE_TIME) | |
6272 | perf_output_put(handle, data->time); | |
6273 | ||
6274 | if (sample_type & PERF_SAMPLE_ID) | |
6275 | perf_output_put(handle, data->id); | |
6276 | ||
6277 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6278 | perf_output_put(handle, data->stream_id); | |
6279 | ||
6280 | if (sample_type & PERF_SAMPLE_CPU) | |
6281 | perf_output_put(handle, data->cpu_entry); | |
ff3d527c AH |
6282 | |
6283 | if (sample_type & PERF_SAMPLE_IDENTIFIER) | |
6284 | perf_output_put(handle, data->id); | |
c980d109 ACM |
6285 | } |
6286 | ||
76369139 FW |
6287 | void perf_event__output_id_sample(struct perf_event *event, |
6288 | struct perf_output_handle *handle, | |
6289 | struct perf_sample_data *sample) | |
c980d109 ACM |
6290 | { |
6291 | if (event->attr.sample_id_all) | |
6292 | __perf_event__output_id_sample(handle, sample); | |
6293 | } | |
6294 | ||
3dab77fb | 6295 | static void perf_output_read_one(struct perf_output_handle *handle, |
eed01528 SE |
6296 | struct perf_event *event, |
6297 | u64 enabled, u64 running) | |
3dab77fb | 6298 | { |
cdd6c482 | 6299 | u64 read_format = event->attr.read_format; |
3dab77fb PZ |
6300 | u64 values[4]; |
6301 | int n = 0; | |
6302 | ||
b5e58793 | 6303 | values[n++] = perf_event_count(event); |
3dab77fb | 6304 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { |
eed01528 | 6305 | values[n++] = enabled + |
cdd6c482 | 6306 | atomic64_read(&event->child_total_time_enabled); |
3dab77fb PZ |
6307 | } |
6308 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { | |
eed01528 | 6309 | values[n++] = running + |
cdd6c482 | 6310 | atomic64_read(&event->child_total_time_running); |
3dab77fb PZ |
6311 | } |
6312 | if (read_format & PERF_FORMAT_ID) | |
cdd6c482 | 6313 | values[n++] = primary_event_id(event); |
3dab77fb | 6314 | |
76369139 | 6315 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
6316 | } |
6317 | ||
3dab77fb | 6318 | static void perf_output_read_group(struct perf_output_handle *handle, |
eed01528 SE |
6319 | struct perf_event *event, |
6320 | u64 enabled, u64 running) | |
3dab77fb | 6321 | { |
cdd6c482 IM |
6322 | struct perf_event *leader = event->group_leader, *sub; |
6323 | u64 read_format = event->attr.read_format; | |
3dab77fb PZ |
6324 | u64 values[5]; |
6325 | int n = 0; | |
6326 | ||
6327 | values[n++] = 1 + leader->nr_siblings; | |
6328 | ||
6329 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
eed01528 | 6330 | values[n++] = enabled; |
3dab77fb PZ |
6331 | |
6332 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
eed01528 | 6333 | values[n++] = running; |
3dab77fb | 6334 | |
9e5b127d PZ |
6335 | if ((leader != event) && |
6336 | (leader->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
6337 | leader->pmu->read(leader); |
6338 | ||
b5e58793 | 6339 | values[n++] = perf_event_count(leader); |
3dab77fb | 6340 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 6341 | values[n++] = primary_event_id(leader); |
3dab77fb | 6342 | |
76369139 | 6343 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb | 6344 | |
edb39592 | 6345 | for_each_sibling_event(sub, leader) { |
3dab77fb PZ |
6346 | n = 0; |
6347 | ||
6f5ab001 JO |
6348 | if ((sub != event) && |
6349 | (sub->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
6350 | sub->pmu->read(sub); |
6351 | ||
b5e58793 | 6352 | values[n++] = perf_event_count(sub); |
3dab77fb | 6353 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 6354 | values[n++] = primary_event_id(sub); |
3dab77fb | 6355 | |
76369139 | 6356 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
6357 | } |
6358 | } | |
6359 | ||
eed01528 SE |
6360 | #define PERF_FORMAT_TOTAL_TIMES (PERF_FORMAT_TOTAL_TIME_ENABLED|\ |
6361 | PERF_FORMAT_TOTAL_TIME_RUNNING) | |
6362 | ||
ba5213ae PZ |
6363 | /* |
6364 | * XXX PERF_SAMPLE_READ vs inherited events seems difficult. | |
6365 | * | |
6366 | * The problem is that its both hard and excessively expensive to iterate the | |
6367 | * child list, not to mention that its impossible to IPI the children running | |
6368 | * on another CPU, from interrupt/NMI context. | |
6369 | */ | |
3dab77fb | 6370 | static void perf_output_read(struct perf_output_handle *handle, |
cdd6c482 | 6371 | struct perf_event *event) |
3dab77fb | 6372 | { |
e3f3541c | 6373 | u64 enabled = 0, running = 0, now; |
eed01528 SE |
6374 | u64 read_format = event->attr.read_format; |
6375 | ||
6376 | /* | |
6377 | * compute total_time_enabled, total_time_running | |
6378 | * based on snapshot values taken when the event | |
6379 | * was last scheduled in. | |
6380 | * | |
6381 | * we cannot simply called update_context_time() | |
6382 | * because of locking issue as we are called in | |
6383 | * NMI context | |
6384 | */ | |
c4794295 | 6385 | if (read_format & PERF_FORMAT_TOTAL_TIMES) |
e3f3541c | 6386 | calc_timer_values(event, &now, &enabled, &running); |
eed01528 | 6387 | |
cdd6c482 | 6388 | if (event->attr.read_format & PERF_FORMAT_GROUP) |
eed01528 | 6389 | perf_output_read_group(handle, event, enabled, running); |
3dab77fb | 6390 | else |
eed01528 | 6391 | perf_output_read_one(handle, event, enabled, running); |
3dab77fb PZ |
6392 | } |
6393 | ||
5622f295 MM |
6394 | void perf_output_sample(struct perf_output_handle *handle, |
6395 | struct perf_event_header *header, | |
6396 | struct perf_sample_data *data, | |
cdd6c482 | 6397 | struct perf_event *event) |
5622f295 MM |
6398 | { |
6399 | u64 sample_type = data->type; | |
6400 | ||
6401 | perf_output_put(handle, *header); | |
6402 | ||
ff3d527c AH |
6403 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
6404 | perf_output_put(handle, data->id); | |
6405 | ||
5622f295 MM |
6406 | if (sample_type & PERF_SAMPLE_IP) |
6407 | perf_output_put(handle, data->ip); | |
6408 | ||
6409 | if (sample_type & PERF_SAMPLE_TID) | |
6410 | perf_output_put(handle, data->tid_entry); | |
6411 | ||
6412 | if (sample_type & PERF_SAMPLE_TIME) | |
6413 | perf_output_put(handle, data->time); | |
6414 | ||
6415 | if (sample_type & PERF_SAMPLE_ADDR) | |
6416 | perf_output_put(handle, data->addr); | |
6417 | ||
6418 | if (sample_type & PERF_SAMPLE_ID) | |
6419 | perf_output_put(handle, data->id); | |
6420 | ||
6421 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6422 | perf_output_put(handle, data->stream_id); | |
6423 | ||
6424 | if (sample_type & PERF_SAMPLE_CPU) | |
6425 | perf_output_put(handle, data->cpu_entry); | |
6426 | ||
6427 | if (sample_type & PERF_SAMPLE_PERIOD) | |
6428 | perf_output_put(handle, data->period); | |
6429 | ||
6430 | if (sample_type & PERF_SAMPLE_READ) | |
cdd6c482 | 6431 | perf_output_read(handle, event); |
5622f295 MM |
6432 | |
6433 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { | |
99e818cc | 6434 | int size = 1; |
5622f295 | 6435 | |
99e818cc JO |
6436 | size += data->callchain->nr; |
6437 | size *= sizeof(u64); | |
6438 | __output_copy(handle, data->callchain, size); | |
5622f295 MM |
6439 | } |
6440 | ||
6441 | if (sample_type & PERF_SAMPLE_RAW) { | |
7e3f977e DB |
6442 | struct perf_raw_record *raw = data->raw; |
6443 | ||
6444 | if (raw) { | |
6445 | struct perf_raw_frag *frag = &raw->frag; | |
6446 | ||
6447 | perf_output_put(handle, raw->size); | |
6448 | do { | |
6449 | if (frag->copy) { | |
6450 | __output_custom(handle, frag->copy, | |
6451 | frag->data, frag->size); | |
6452 | } else { | |
6453 | __output_copy(handle, frag->data, | |
6454 | frag->size); | |
6455 | } | |
6456 | if (perf_raw_frag_last(frag)) | |
6457 | break; | |
6458 | frag = frag->next; | |
6459 | } while (1); | |
6460 | if (frag->pad) | |
6461 | __output_skip(handle, NULL, frag->pad); | |
5622f295 MM |
6462 | } else { |
6463 | struct { | |
6464 | u32 size; | |
6465 | u32 data; | |
6466 | } raw = { | |
6467 | .size = sizeof(u32), | |
6468 | .data = 0, | |
6469 | }; | |
6470 | perf_output_put(handle, raw); | |
6471 | } | |
6472 | } | |
a7ac67ea | 6473 | |
bce38cd5 SE |
6474 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { |
6475 | if (data->br_stack) { | |
6476 | size_t size; | |
6477 | ||
6478 | size = data->br_stack->nr | |
6479 | * sizeof(struct perf_branch_entry); | |
6480 | ||
6481 | perf_output_put(handle, data->br_stack->nr); | |
6482 | perf_output_copy(handle, data->br_stack->entries, size); | |
6483 | } else { | |
6484 | /* | |
6485 | * we always store at least the value of nr | |
6486 | */ | |
6487 | u64 nr = 0; | |
6488 | perf_output_put(handle, nr); | |
6489 | } | |
6490 | } | |
4018994f JO |
6491 | |
6492 | if (sample_type & PERF_SAMPLE_REGS_USER) { | |
6493 | u64 abi = data->regs_user.abi; | |
6494 | ||
6495 | /* | |
6496 | * If there are no regs to dump, notice it through | |
6497 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
6498 | */ | |
6499 | perf_output_put(handle, abi); | |
6500 | ||
6501 | if (abi) { | |
6502 | u64 mask = event->attr.sample_regs_user; | |
6503 | perf_output_sample_regs(handle, | |
6504 | data->regs_user.regs, | |
6505 | mask); | |
6506 | } | |
6507 | } | |
c5ebcedb | 6508 | |
a5cdd40c | 6509 | if (sample_type & PERF_SAMPLE_STACK_USER) { |
c5ebcedb JO |
6510 | perf_output_sample_ustack(handle, |
6511 | data->stack_user_size, | |
6512 | data->regs_user.regs); | |
a5cdd40c | 6513 | } |
c3feedf2 AK |
6514 | |
6515 | if (sample_type & PERF_SAMPLE_WEIGHT) | |
6516 | perf_output_put(handle, data->weight); | |
d6be9ad6 SE |
6517 | |
6518 | if (sample_type & PERF_SAMPLE_DATA_SRC) | |
6519 | perf_output_put(handle, data->data_src.val); | |
a5cdd40c | 6520 | |
fdfbbd07 AK |
6521 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
6522 | perf_output_put(handle, data->txn); | |
6523 | ||
60e2364e SE |
6524 | if (sample_type & PERF_SAMPLE_REGS_INTR) { |
6525 | u64 abi = data->regs_intr.abi; | |
6526 | /* | |
6527 | * If there are no regs to dump, notice it through | |
6528 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
6529 | */ | |
6530 | perf_output_put(handle, abi); | |
6531 | ||
6532 | if (abi) { | |
6533 | u64 mask = event->attr.sample_regs_intr; | |
6534 | ||
6535 | perf_output_sample_regs(handle, | |
6536 | data->regs_intr.regs, | |
6537 | mask); | |
6538 | } | |
6539 | } | |
6540 | ||
fc7ce9c7 KL |
6541 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) |
6542 | perf_output_put(handle, data->phys_addr); | |
6543 | ||
a5cdd40c PZ |
6544 | if (!event->attr.watermark) { |
6545 | int wakeup_events = event->attr.wakeup_events; | |
6546 | ||
6547 | if (wakeup_events) { | |
6548 | struct ring_buffer *rb = handle->rb; | |
6549 | int events = local_inc_return(&rb->events); | |
6550 | ||
6551 | if (events >= wakeup_events) { | |
6552 | local_sub(wakeup_events, &rb->events); | |
6553 | local_inc(&rb->wakeup); | |
6554 | } | |
6555 | } | |
6556 | } | |
5622f295 MM |
6557 | } |
6558 | ||
fc7ce9c7 KL |
6559 | static u64 perf_virt_to_phys(u64 virt) |
6560 | { | |
6561 | u64 phys_addr = 0; | |
6562 | struct page *p = NULL; | |
6563 | ||
6564 | if (!virt) | |
6565 | return 0; | |
6566 | ||
6567 | if (virt >= TASK_SIZE) { | |
6568 | /* If it's vmalloc()d memory, leave phys_addr as 0 */ | |
6569 | if (virt_addr_valid((void *)(uintptr_t)virt) && | |
6570 | !(virt >= VMALLOC_START && virt < VMALLOC_END)) | |
6571 | phys_addr = (u64)virt_to_phys((void *)(uintptr_t)virt); | |
6572 | } else { | |
6573 | /* | |
6574 | * Walking the pages tables for user address. | |
6575 | * Interrupts are disabled, so it prevents any tear down | |
6576 | * of the page tables. | |
6577 | * Try IRQ-safe __get_user_pages_fast first. | |
6578 | * If failed, leave phys_addr as 0. | |
6579 | */ | |
6580 | if ((current->mm != NULL) && | |
6581 | (__get_user_pages_fast(virt, 1, 0, &p) == 1)) | |
6582 | phys_addr = page_to_phys(p) + virt % PAGE_SIZE; | |
6583 | ||
6584 | if (p) | |
6585 | put_page(p); | |
6586 | } | |
6587 | ||
6588 | return phys_addr; | |
6589 | } | |
6590 | ||
99e818cc JO |
6591 | static struct perf_callchain_entry __empty_callchain = { .nr = 0, }; |
6592 | ||
6cbc304f | 6593 | struct perf_callchain_entry * |
8cf7e0e2 JO |
6594 | perf_callchain(struct perf_event *event, struct pt_regs *regs) |
6595 | { | |
6596 | bool kernel = !event->attr.exclude_callchain_kernel; | |
6597 | bool user = !event->attr.exclude_callchain_user; | |
6598 | /* Disallow cross-task user callchains. */ | |
6599 | bool crosstask = event->ctx->task && event->ctx->task != current; | |
6600 | const u32 max_stack = event->attr.sample_max_stack; | |
99e818cc | 6601 | struct perf_callchain_entry *callchain; |
8cf7e0e2 JO |
6602 | |
6603 | if (!kernel && !user) | |
99e818cc | 6604 | return &__empty_callchain; |
8cf7e0e2 | 6605 | |
99e818cc JO |
6606 | callchain = get_perf_callchain(regs, 0, kernel, user, |
6607 | max_stack, crosstask, true); | |
6608 | return callchain ?: &__empty_callchain; | |
8cf7e0e2 JO |
6609 | } |
6610 | ||
5622f295 MM |
6611 | void perf_prepare_sample(struct perf_event_header *header, |
6612 | struct perf_sample_data *data, | |
cdd6c482 | 6613 | struct perf_event *event, |
5622f295 | 6614 | struct pt_regs *regs) |
7b732a75 | 6615 | { |
cdd6c482 | 6616 | u64 sample_type = event->attr.sample_type; |
7b732a75 | 6617 | |
cdd6c482 | 6618 | header->type = PERF_RECORD_SAMPLE; |
c320c7b7 | 6619 | header->size = sizeof(*header) + event->header_size; |
5622f295 MM |
6620 | |
6621 | header->misc = 0; | |
6622 | header->misc |= perf_misc_flags(regs); | |
6fab0192 | 6623 | |
c980d109 | 6624 | __perf_event_header__init_id(header, data, event); |
6844c09d | 6625 | |
c320c7b7 | 6626 | if (sample_type & PERF_SAMPLE_IP) |
5622f295 MM |
6627 | data->ip = perf_instruction_pointer(regs); |
6628 | ||
b23f3325 | 6629 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { |
5622f295 | 6630 | int size = 1; |
394ee076 | 6631 | |
6cbc304f PZ |
6632 | if (!(sample_type & __PERF_SAMPLE_CALLCHAIN_EARLY)) |
6633 | data->callchain = perf_callchain(event, regs); | |
6634 | ||
99e818cc | 6635 | size += data->callchain->nr; |
5622f295 MM |
6636 | |
6637 | header->size += size * sizeof(u64); | |
394ee076 PZ |
6638 | } |
6639 | ||
3a43ce68 | 6640 | if (sample_type & PERF_SAMPLE_RAW) { |
7e3f977e DB |
6641 | struct perf_raw_record *raw = data->raw; |
6642 | int size; | |
6643 | ||
6644 | if (raw) { | |
6645 | struct perf_raw_frag *frag = &raw->frag; | |
6646 | u32 sum = 0; | |
6647 | ||
6648 | do { | |
6649 | sum += frag->size; | |
6650 | if (perf_raw_frag_last(frag)) | |
6651 | break; | |
6652 | frag = frag->next; | |
6653 | } while (1); | |
6654 | ||
6655 | size = round_up(sum + sizeof(u32), sizeof(u64)); | |
6656 | raw->size = size - sizeof(u32); | |
6657 | frag->pad = raw->size - sum; | |
6658 | } else { | |
6659 | size = sizeof(u64); | |
6660 | } | |
a044560c | 6661 | |
7e3f977e | 6662 | header->size += size; |
7f453c24 | 6663 | } |
bce38cd5 SE |
6664 | |
6665 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { | |
6666 | int size = sizeof(u64); /* nr */ | |
6667 | if (data->br_stack) { | |
6668 | size += data->br_stack->nr | |
6669 | * sizeof(struct perf_branch_entry); | |
6670 | } | |
6671 | header->size += size; | |
6672 | } | |
4018994f | 6673 | |
2565711f | 6674 | if (sample_type & (PERF_SAMPLE_REGS_USER | PERF_SAMPLE_STACK_USER)) |
88a7c26a AL |
6675 | perf_sample_regs_user(&data->regs_user, regs, |
6676 | &data->regs_user_copy); | |
2565711f | 6677 | |
4018994f JO |
6678 | if (sample_type & PERF_SAMPLE_REGS_USER) { |
6679 | /* regs dump ABI info */ | |
6680 | int size = sizeof(u64); | |
6681 | ||
4018994f JO |
6682 | if (data->regs_user.regs) { |
6683 | u64 mask = event->attr.sample_regs_user; | |
6684 | size += hweight64(mask) * sizeof(u64); | |
6685 | } | |
6686 | ||
6687 | header->size += size; | |
6688 | } | |
c5ebcedb JO |
6689 | |
6690 | if (sample_type & PERF_SAMPLE_STACK_USER) { | |
6691 | /* | |
9f014e3a | 6692 | * Either we need PERF_SAMPLE_STACK_USER bit to be always |
c5ebcedb JO |
6693 | * processed as the last one or have additional check added |
6694 | * in case new sample type is added, because we could eat | |
6695 | * up the rest of the sample size. | |
6696 | */ | |
c5ebcedb JO |
6697 | u16 stack_size = event->attr.sample_stack_user; |
6698 | u16 size = sizeof(u64); | |
6699 | ||
c5ebcedb | 6700 | stack_size = perf_sample_ustack_size(stack_size, header->size, |
2565711f | 6701 | data->regs_user.regs); |
c5ebcedb JO |
6702 | |
6703 | /* | |
6704 | * If there is something to dump, add space for the dump | |
6705 | * itself and for the field that tells the dynamic size, | |
6706 | * which is how many have been actually dumped. | |
6707 | */ | |
6708 | if (stack_size) | |
6709 | size += sizeof(u64) + stack_size; | |
6710 | ||
6711 | data->stack_user_size = stack_size; | |
6712 | header->size += size; | |
6713 | } | |
60e2364e SE |
6714 | |
6715 | if (sample_type & PERF_SAMPLE_REGS_INTR) { | |
6716 | /* regs dump ABI info */ | |
6717 | int size = sizeof(u64); | |
6718 | ||
6719 | perf_sample_regs_intr(&data->regs_intr, regs); | |
6720 | ||
6721 | if (data->regs_intr.regs) { | |
6722 | u64 mask = event->attr.sample_regs_intr; | |
6723 | ||
6724 | size += hweight64(mask) * sizeof(u64); | |
6725 | } | |
6726 | ||
6727 | header->size += size; | |
6728 | } | |
fc7ce9c7 KL |
6729 | |
6730 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) | |
6731 | data->phys_addr = perf_virt_to_phys(data->addr); | |
5622f295 | 6732 | } |
7f453c24 | 6733 | |
56201969 | 6734 | static __always_inline int |
9ecda41a WN |
6735 | __perf_event_output(struct perf_event *event, |
6736 | struct perf_sample_data *data, | |
6737 | struct pt_regs *regs, | |
6738 | int (*output_begin)(struct perf_output_handle *, | |
6739 | struct perf_event *, | |
6740 | unsigned int)) | |
5622f295 MM |
6741 | { |
6742 | struct perf_output_handle handle; | |
6743 | struct perf_event_header header; | |
56201969 | 6744 | int err; |
689802b2 | 6745 | |
927c7a9e FW |
6746 | /* protect the callchain buffers */ |
6747 | rcu_read_lock(); | |
6748 | ||
cdd6c482 | 6749 | perf_prepare_sample(&header, data, event, regs); |
5c148194 | 6750 | |
56201969 ACM |
6751 | err = output_begin(&handle, event, header.size); |
6752 | if (err) | |
927c7a9e | 6753 | goto exit; |
0322cd6e | 6754 | |
cdd6c482 | 6755 | perf_output_sample(&handle, &header, data, event); |
f413cdb8 | 6756 | |
8a057d84 | 6757 | perf_output_end(&handle); |
927c7a9e FW |
6758 | |
6759 | exit: | |
6760 | rcu_read_unlock(); | |
56201969 | 6761 | return err; |
0322cd6e PZ |
6762 | } |
6763 | ||
9ecda41a WN |
6764 | void |
6765 | perf_event_output_forward(struct perf_event *event, | |
6766 | struct perf_sample_data *data, | |
6767 | struct pt_regs *regs) | |
6768 | { | |
6769 | __perf_event_output(event, data, regs, perf_output_begin_forward); | |
6770 | } | |
6771 | ||
6772 | void | |
6773 | perf_event_output_backward(struct perf_event *event, | |
6774 | struct perf_sample_data *data, | |
6775 | struct pt_regs *regs) | |
6776 | { | |
6777 | __perf_event_output(event, data, regs, perf_output_begin_backward); | |
6778 | } | |
6779 | ||
56201969 | 6780 | int |
9ecda41a WN |
6781 | perf_event_output(struct perf_event *event, |
6782 | struct perf_sample_data *data, | |
6783 | struct pt_regs *regs) | |
6784 | { | |
56201969 | 6785 | return __perf_event_output(event, data, regs, perf_output_begin); |
9ecda41a WN |
6786 | } |
6787 | ||
38b200d6 | 6788 | /* |
cdd6c482 | 6789 | * read event_id |
38b200d6 PZ |
6790 | */ |
6791 | ||
6792 | struct perf_read_event { | |
6793 | struct perf_event_header header; | |
6794 | ||
6795 | u32 pid; | |
6796 | u32 tid; | |
38b200d6 PZ |
6797 | }; |
6798 | ||
6799 | static void | |
cdd6c482 | 6800 | perf_event_read_event(struct perf_event *event, |
38b200d6 PZ |
6801 | struct task_struct *task) |
6802 | { | |
6803 | struct perf_output_handle handle; | |
c980d109 | 6804 | struct perf_sample_data sample; |
dfc65094 | 6805 | struct perf_read_event read_event = { |
38b200d6 | 6806 | .header = { |
cdd6c482 | 6807 | .type = PERF_RECORD_READ, |
38b200d6 | 6808 | .misc = 0, |
c320c7b7 | 6809 | .size = sizeof(read_event) + event->read_size, |
38b200d6 | 6810 | }, |
cdd6c482 IM |
6811 | .pid = perf_event_pid(event, task), |
6812 | .tid = perf_event_tid(event, task), | |
38b200d6 | 6813 | }; |
3dab77fb | 6814 | int ret; |
38b200d6 | 6815 | |
c980d109 | 6816 | perf_event_header__init_id(&read_event.header, &sample, event); |
a7ac67ea | 6817 | ret = perf_output_begin(&handle, event, read_event.header.size); |
38b200d6 PZ |
6818 | if (ret) |
6819 | return; | |
6820 | ||
dfc65094 | 6821 | perf_output_put(&handle, read_event); |
cdd6c482 | 6822 | perf_output_read(&handle, event); |
c980d109 | 6823 | perf_event__output_id_sample(event, &handle, &sample); |
3dab77fb | 6824 | |
38b200d6 PZ |
6825 | perf_output_end(&handle); |
6826 | } | |
6827 | ||
aab5b71e | 6828 | typedef void (perf_iterate_f)(struct perf_event *event, void *data); |
52d857a8 JO |
6829 | |
6830 | static void | |
aab5b71e PZ |
6831 | perf_iterate_ctx(struct perf_event_context *ctx, |
6832 | perf_iterate_f output, | |
b73e4fef | 6833 | void *data, bool all) |
52d857a8 JO |
6834 | { |
6835 | struct perf_event *event; | |
6836 | ||
6837 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
b73e4fef AS |
6838 | if (!all) { |
6839 | if (event->state < PERF_EVENT_STATE_INACTIVE) | |
6840 | continue; | |
6841 | if (!event_filter_match(event)) | |
6842 | continue; | |
6843 | } | |
6844 | ||
67516844 | 6845 | output(event, data); |
52d857a8 JO |
6846 | } |
6847 | } | |
6848 | ||
aab5b71e | 6849 | static void perf_iterate_sb_cpu(perf_iterate_f output, void *data) |
f2fb6bef KL |
6850 | { |
6851 | struct pmu_event_list *pel = this_cpu_ptr(&pmu_sb_events); | |
6852 | struct perf_event *event; | |
6853 | ||
6854 | list_for_each_entry_rcu(event, &pel->list, sb_list) { | |
0b8f1e2e PZ |
6855 | /* |
6856 | * Skip events that are not fully formed yet; ensure that | |
6857 | * if we observe event->ctx, both event and ctx will be | |
6858 | * complete enough. See perf_install_in_context(). | |
6859 | */ | |
6860 | if (!smp_load_acquire(&event->ctx)) | |
6861 | continue; | |
6862 | ||
f2fb6bef KL |
6863 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
6864 | continue; | |
6865 | if (!event_filter_match(event)) | |
6866 | continue; | |
6867 | output(event, data); | |
6868 | } | |
6869 | } | |
6870 | ||
aab5b71e PZ |
6871 | /* |
6872 | * Iterate all events that need to receive side-band events. | |
6873 | * | |
6874 | * For new callers; ensure that account_pmu_sb_event() includes | |
6875 | * your event, otherwise it might not get delivered. | |
6876 | */ | |
52d857a8 | 6877 | static void |
aab5b71e | 6878 | perf_iterate_sb(perf_iterate_f output, void *data, |
52d857a8 JO |
6879 | struct perf_event_context *task_ctx) |
6880 | { | |
52d857a8 | 6881 | struct perf_event_context *ctx; |
52d857a8 JO |
6882 | int ctxn; |
6883 | ||
aab5b71e PZ |
6884 | rcu_read_lock(); |
6885 | preempt_disable(); | |
6886 | ||
4e93ad60 | 6887 | /* |
aab5b71e PZ |
6888 | * If we have task_ctx != NULL we only notify the task context itself. |
6889 | * The task_ctx is set only for EXIT events before releasing task | |
4e93ad60 JO |
6890 | * context. |
6891 | */ | |
6892 | if (task_ctx) { | |
aab5b71e PZ |
6893 | perf_iterate_ctx(task_ctx, output, data, false); |
6894 | goto done; | |
4e93ad60 JO |
6895 | } |
6896 | ||
aab5b71e | 6897 | perf_iterate_sb_cpu(output, data); |
f2fb6bef KL |
6898 | |
6899 | for_each_task_context_nr(ctxn) { | |
52d857a8 JO |
6900 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); |
6901 | if (ctx) | |
aab5b71e | 6902 | perf_iterate_ctx(ctx, output, data, false); |
52d857a8 | 6903 | } |
aab5b71e | 6904 | done: |
f2fb6bef | 6905 | preempt_enable(); |
52d857a8 | 6906 | rcu_read_unlock(); |
95ff4ca2 AS |
6907 | } |
6908 | ||
375637bc AS |
6909 | /* |
6910 | * Clear all file-based filters at exec, they'll have to be | |
6911 | * re-instated when/if these objects are mmapped again. | |
6912 | */ | |
6913 | static void perf_event_addr_filters_exec(struct perf_event *event, void *data) | |
6914 | { | |
6915 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
6916 | struct perf_addr_filter *filter; | |
6917 | unsigned int restart = 0, count = 0; | |
6918 | unsigned long flags; | |
6919 | ||
6920 | if (!has_addr_filter(event)) | |
6921 | return; | |
6922 | ||
6923 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
6924 | list_for_each_entry(filter, &ifh->list, entry) { | |
9511bce9 | 6925 | if (filter->path.dentry) { |
c60f83b8 AS |
6926 | event->addr_filter_ranges[count].start = 0; |
6927 | event->addr_filter_ranges[count].size = 0; | |
375637bc AS |
6928 | restart++; |
6929 | } | |
6930 | ||
6931 | count++; | |
6932 | } | |
6933 | ||
6934 | if (restart) | |
6935 | event->addr_filters_gen++; | |
6936 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
6937 | ||
6938 | if (restart) | |
767ae086 | 6939 | perf_event_stop(event, 1); |
375637bc AS |
6940 | } |
6941 | ||
6942 | void perf_event_exec(void) | |
6943 | { | |
6944 | struct perf_event_context *ctx; | |
6945 | int ctxn; | |
6946 | ||
6947 | rcu_read_lock(); | |
6948 | for_each_task_context_nr(ctxn) { | |
6949 | ctx = current->perf_event_ctxp[ctxn]; | |
6950 | if (!ctx) | |
6951 | continue; | |
6952 | ||
6953 | perf_event_enable_on_exec(ctxn); | |
6954 | ||
aab5b71e | 6955 | perf_iterate_ctx(ctx, perf_event_addr_filters_exec, NULL, |
375637bc AS |
6956 | true); |
6957 | } | |
6958 | rcu_read_unlock(); | |
6959 | } | |
6960 | ||
95ff4ca2 AS |
6961 | struct remote_output { |
6962 | struct ring_buffer *rb; | |
6963 | int err; | |
6964 | }; | |
6965 | ||
6966 | static void __perf_event_output_stop(struct perf_event *event, void *data) | |
6967 | { | |
6968 | struct perf_event *parent = event->parent; | |
6969 | struct remote_output *ro = data; | |
6970 | struct ring_buffer *rb = ro->rb; | |
375637bc AS |
6971 | struct stop_event_data sd = { |
6972 | .event = event, | |
6973 | }; | |
95ff4ca2 AS |
6974 | |
6975 | if (!has_aux(event)) | |
6976 | return; | |
6977 | ||
6978 | if (!parent) | |
6979 | parent = event; | |
6980 | ||
6981 | /* | |
6982 | * In case of inheritance, it will be the parent that links to the | |
767ae086 AS |
6983 | * ring-buffer, but it will be the child that's actually using it. |
6984 | * | |
6985 | * We are using event::rb to determine if the event should be stopped, | |
6986 | * however this may race with ring_buffer_attach() (through set_output), | |
6987 | * which will make us skip the event that actually needs to be stopped. | |
6988 | * So ring_buffer_attach() has to stop an aux event before re-assigning | |
6989 | * its rb pointer. | |
95ff4ca2 AS |
6990 | */ |
6991 | if (rcu_dereference(parent->rb) == rb) | |
375637bc | 6992 | ro->err = __perf_event_stop(&sd); |
95ff4ca2 AS |
6993 | } |
6994 | ||
6995 | static int __perf_pmu_output_stop(void *info) | |
6996 | { | |
6997 | struct perf_event *event = info; | |
f3a519e4 | 6998 | struct pmu *pmu = event->ctx->pmu; |
8b6a3fe8 | 6999 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
95ff4ca2 AS |
7000 | struct remote_output ro = { |
7001 | .rb = event->rb, | |
7002 | }; | |
7003 | ||
7004 | rcu_read_lock(); | |
aab5b71e | 7005 | perf_iterate_ctx(&cpuctx->ctx, __perf_event_output_stop, &ro, false); |
95ff4ca2 | 7006 | if (cpuctx->task_ctx) |
aab5b71e | 7007 | perf_iterate_ctx(cpuctx->task_ctx, __perf_event_output_stop, |
b73e4fef | 7008 | &ro, false); |
95ff4ca2 AS |
7009 | rcu_read_unlock(); |
7010 | ||
7011 | return ro.err; | |
7012 | } | |
7013 | ||
7014 | static void perf_pmu_output_stop(struct perf_event *event) | |
7015 | { | |
7016 | struct perf_event *iter; | |
7017 | int err, cpu; | |
7018 | ||
7019 | restart: | |
7020 | rcu_read_lock(); | |
7021 | list_for_each_entry_rcu(iter, &event->rb->event_list, rb_entry) { | |
7022 | /* | |
7023 | * For per-CPU events, we need to make sure that neither they | |
7024 | * nor their children are running; for cpu==-1 events it's | |
7025 | * sufficient to stop the event itself if it's active, since | |
7026 | * it can't have children. | |
7027 | */ | |
7028 | cpu = iter->cpu; | |
7029 | if (cpu == -1) | |
7030 | cpu = READ_ONCE(iter->oncpu); | |
7031 | ||
7032 | if (cpu == -1) | |
7033 | continue; | |
7034 | ||
7035 | err = cpu_function_call(cpu, __perf_pmu_output_stop, event); | |
7036 | if (err == -EAGAIN) { | |
7037 | rcu_read_unlock(); | |
7038 | goto restart; | |
7039 | } | |
7040 | } | |
7041 | rcu_read_unlock(); | |
52d857a8 JO |
7042 | } |
7043 | ||
60313ebe | 7044 | /* |
9f498cc5 PZ |
7045 | * task tracking -- fork/exit |
7046 | * | |
13d7a241 | 7047 | * enabled by: attr.comm | attr.mmap | attr.mmap2 | attr.mmap_data | attr.task |
60313ebe PZ |
7048 | */ |
7049 | ||
9f498cc5 | 7050 | struct perf_task_event { |
3a80b4a3 | 7051 | struct task_struct *task; |
cdd6c482 | 7052 | struct perf_event_context *task_ctx; |
60313ebe PZ |
7053 | |
7054 | struct { | |
7055 | struct perf_event_header header; | |
7056 | ||
7057 | u32 pid; | |
7058 | u32 ppid; | |
9f498cc5 PZ |
7059 | u32 tid; |
7060 | u32 ptid; | |
393b2ad8 | 7061 | u64 time; |
cdd6c482 | 7062 | } event_id; |
60313ebe PZ |
7063 | }; |
7064 | ||
67516844 JO |
7065 | static int perf_event_task_match(struct perf_event *event) |
7066 | { | |
13d7a241 SE |
7067 | return event->attr.comm || event->attr.mmap || |
7068 | event->attr.mmap2 || event->attr.mmap_data || | |
7069 | event->attr.task; | |
67516844 JO |
7070 | } |
7071 | ||
cdd6c482 | 7072 | static void perf_event_task_output(struct perf_event *event, |
52d857a8 | 7073 | void *data) |
60313ebe | 7074 | { |
52d857a8 | 7075 | struct perf_task_event *task_event = data; |
60313ebe | 7076 | struct perf_output_handle handle; |
c980d109 | 7077 | struct perf_sample_data sample; |
9f498cc5 | 7078 | struct task_struct *task = task_event->task; |
c980d109 | 7079 | int ret, size = task_event->event_id.header.size; |
8bb39f9a | 7080 | |
67516844 JO |
7081 | if (!perf_event_task_match(event)) |
7082 | return; | |
7083 | ||
c980d109 | 7084 | perf_event_header__init_id(&task_event->event_id.header, &sample, event); |
60313ebe | 7085 | |
c980d109 | 7086 | ret = perf_output_begin(&handle, event, |
a7ac67ea | 7087 | task_event->event_id.header.size); |
ef60777c | 7088 | if (ret) |
c980d109 | 7089 | goto out; |
60313ebe | 7090 | |
cdd6c482 IM |
7091 | task_event->event_id.pid = perf_event_pid(event, task); |
7092 | task_event->event_id.ppid = perf_event_pid(event, current); | |
60313ebe | 7093 | |
cdd6c482 IM |
7094 | task_event->event_id.tid = perf_event_tid(event, task); |
7095 | task_event->event_id.ptid = perf_event_tid(event, current); | |
9f498cc5 | 7096 | |
34f43927 PZ |
7097 | task_event->event_id.time = perf_event_clock(event); |
7098 | ||
cdd6c482 | 7099 | perf_output_put(&handle, task_event->event_id); |
393b2ad8 | 7100 | |
c980d109 ACM |
7101 | perf_event__output_id_sample(event, &handle, &sample); |
7102 | ||
60313ebe | 7103 | perf_output_end(&handle); |
c980d109 ACM |
7104 | out: |
7105 | task_event->event_id.header.size = size; | |
60313ebe PZ |
7106 | } |
7107 | ||
cdd6c482 IM |
7108 | static void perf_event_task(struct task_struct *task, |
7109 | struct perf_event_context *task_ctx, | |
3a80b4a3 | 7110 | int new) |
60313ebe | 7111 | { |
9f498cc5 | 7112 | struct perf_task_event task_event; |
60313ebe | 7113 | |
cdd6c482 IM |
7114 | if (!atomic_read(&nr_comm_events) && |
7115 | !atomic_read(&nr_mmap_events) && | |
7116 | !atomic_read(&nr_task_events)) | |
60313ebe PZ |
7117 | return; |
7118 | ||
9f498cc5 | 7119 | task_event = (struct perf_task_event){ |
3a80b4a3 PZ |
7120 | .task = task, |
7121 | .task_ctx = task_ctx, | |
cdd6c482 | 7122 | .event_id = { |
60313ebe | 7123 | .header = { |
cdd6c482 | 7124 | .type = new ? PERF_RECORD_FORK : PERF_RECORD_EXIT, |
573402db | 7125 | .misc = 0, |
cdd6c482 | 7126 | .size = sizeof(task_event.event_id), |
60313ebe | 7127 | }, |
573402db PZ |
7128 | /* .pid */ |
7129 | /* .ppid */ | |
9f498cc5 PZ |
7130 | /* .tid */ |
7131 | /* .ptid */ | |
34f43927 | 7132 | /* .time */ |
60313ebe PZ |
7133 | }, |
7134 | }; | |
7135 | ||
aab5b71e | 7136 | perf_iterate_sb(perf_event_task_output, |
52d857a8 JO |
7137 | &task_event, |
7138 | task_ctx); | |
9f498cc5 PZ |
7139 | } |
7140 | ||
cdd6c482 | 7141 | void perf_event_fork(struct task_struct *task) |
9f498cc5 | 7142 | { |
cdd6c482 | 7143 | perf_event_task(task, NULL, 1); |
e4222673 | 7144 | perf_event_namespaces(task); |
60313ebe PZ |
7145 | } |
7146 | ||
8d1b2d93 PZ |
7147 | /* |
7148 | * comm tracking | |
7149 | */ | |
7150 | ||
7151 | struct perf_comm_event { | |
22a4f650 IM |
7152 | struct task_struct *task; |
7153 | char *comm; | |
8d1b2d93 PZ |
7154 | int comm_size; |
7155 | ||
7156 | struct { | |
7157 | struct perf_event_header header; | |
7158 | ||
7159 | u32 pid; | |
7160 | u32 tid; | |
cdd6c482 | 7161 | } event_id; |
8d1b2d93 PZ |
7162 | }; |
7163 | ||
67516844 JO |
7164 | static int perf_event_comm_match(struct perf_event *event) |
7165 | { | |
7166 | return event->attr.comm; | |
7167 | } | |
7168 | ||
cdd6c482 | 7169 | static void perf_event_comm_output(struct perf_event *event, |
52d857a8 | 7170 | void *data) |
8d1b2d93 | 7171 | { |
52d857a8 | 7172 | struct perf_comm_event *comm_event = data; |
8d1b2d93 | 7173 | struct perf_output_handle handle; |
c980d109 | 7174 | struct perf_sample_data sample; |
cdd6c482 | 7175 | int size = comm_event->event_id.header.size; |
c980d109 ACM |
7176 | int ret; |
7177 | ||
67516844 JO |
7178 | if (!perf_event_comm_match(event)) |
7179 | return; | |
7180 | ||
c980d109 ACM |
7181 | perf_event_header__init_id(&comm_event->event_id.header, &sample, event); |
7182 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 7183 | comm_event->event_id.header.size); |
8d1b2d93 PZ |
7184 | |
7185 | if (ret) | |
c980d109 | 7186 | goto out; |
8d1b2d93 | 7187 | |
cdd6c482 IM |
7188 | comm_event->event_id.pid = perf_event_pid(event, comm_event->task); |
7189 | comm_event->event_id.tid = perf_event_tid(event, comm_event->task); | |
709e50cf | 7190 | |
cdd6c482 | 7191 | perf_output_put(&handle, comm_event->event_id); |
76369139 | 7192 | __output_copy(&handle, comm_event->comm, |
8d1b2d93 | 7193 | comm_event->comm_size); |
c980d109 ACM |
7194 | |
7195 | perf_event__output_id_sample(event, &handle, &sample); | |
7196 | ||
8d1b2d93 | 7197 | perf_output_end(&handle); |
c980d109 ACM |
7198 | out: |
7199 | comm_event->event_id.header.size = size; | |
8d1b2d93 PZ |
7200 | } |
7201 | ||
cdd6c482 | 7202 | static void perf_event_comm_event(struct perf_comm_event *comm_event) |
8d1b2d93 | 7203 | { |
413ee3b4 | 7204 | char comm[TASK_COMM_LEN]; |
8d1b2d93 | 7205 | unsigned int size; |
8d1b2d93 | 7206 | |
413ee3b4 | 7207 | memset(comm, 0, sizeof(comm)); |
96b02d78 | 7208 | strlcpy(comm, comm_event->task->comm, sizeof(comm)); |
888fcee0 | 7209 | size = ALIGN(strlen(comm)+1, sizeof(u64)); |
8d1b2d93 PZ |
7210 | |
7211 | comm_event->comm = comm; | |
7212 | comm_event->comm_size = size; | |
7213 | ||
cdd6c482 | 7214 | comm_event->event_id.header.size = sizeof(comm_event->event_id) + size; |
8dc85d54 | 7215 | |
aab5b71e | 7216 | perf_iterate_sb(perf_event_comm_output, |
52d857a8 JO |
7217 | comm_event, |
7218 | NULL); | |
8d1b2d93 PZ |
7219 | } |
7220 | ||
82b89778 | 7221 | void perf_event_comm(struct task_struct *task, bool exec) |
8d1b2d93 | 7222 | { |
9ee318a7 PZ |
7223 | struct perf_comm_event comm_event; |
7224 | ||
cdd6c482 | 7225 | if (!atomic_read(&nr_comm_events)) |
9ee318a7 | 7226 | return; |
a63eaf34 | 7227 | |
9ee318a7 | 7228 | comm_event = (struct perf_comm_event){ |
8d1b2d93 | 7229 | .task = task, |
573402db PZ |
7230 | /* .comm */ |
7231 | /* .comm_size */ | |
cdd6c482 | 7232 | .event_id = { |
573402db | 7233 | .header = { |
cdd6c482 | 7234 | .type = PERF_RECORD_COMM, |
82b89778 | 7235 | .misc = exec ? PERF_RECORD_MISC_COMM_EXEC : 0, |
573402db PZ |
7236 | /* .size */ |
7237 | }, | |
7238 | /* .pid */ | |
7239 | /* .tid */ | |
8d1b2d93 PZ |
7240 | }, |
7241 | }; | |
7242 | ||
cdd6c482 | 7243 | perf_event_comm_event(&comm_event); |
8d1b2d93 PZ |
7244 | } |
7245 | ||
e4222673 HB |
7246 | /* |
7247 | * namespaces tracking | |
7248 | */ | |
7249 | ||
7250 | struct perf_namespaces_event { | |
7251 | struct task_struct *task; | |
7252 | ||
7253 | struct { | |
7254 | struct perf_event_header header; | |
7255 | ||
7256 | u32 pid; | |
7257 | u32 tid; | |
7258 | u64 nr_namespaces; | |
7259 | struct perf_ns_link_info link_info[NR_NAMESPACES]; | |
7260 | } event_id; | |
7261 | }; | |
7262 | ||
7263 | static int perf_event_namespaces_match(struct perf_event *event) | |
7264 | { | |
7265 | return event->attr.namespaces; | |
7266 | } | |
7267 | ||
7268 | static void perf_event_namespaces_output(struct perf_event *event, | |
7269 | void *data) | |
7270 | { | |
7271 | struct perf_namespaces_event *namespaces_event = data; | |
7272 | struct perf_output_handle handle; | |
7273 | struct perf_sample_data sample; | |
34900ec5 | 7274 | u16 header_size = namespaces_event->event_id.header.size; |
e4222673 HB |
7275 | int ret; |
7276 | ||
7277 | if (!perf_event_namespaces_match(event)) | |
7278 | return; | |
7279 | ||
7280 | perf_event_header__init_id(&namespaces_event->event_id.header, | |
7281 | &sample, event); | |
7282 | ret = perf_output_begin(&handle, event, | |
7283 | namespaces_event->event_id.header.size); | |
7284 | if (ret) | |
34900ec5 | 7285 | goto out; |
e4222673 HB |
7286 | |
7287 | namespaces_event->event_id.pid = perf_event_pid(event, | |
7288 | namespaces_event->task); | |
7289 | namespaces_event->event_id.tid = perf_event_tid(event, | |
7290 | namespaces_event->task); | |
7291 | ||
7292 | perf_output_put(&handle, namespaces_event->event_id); | |
7293 | ||
7294 | perf_event__output_id_sample(event, &handle, &sample); | |
7295 | ||
7296 | perf_output_end(&handle); | |
34900ec5 JO |
7297 | out: |
7298 | namespaces_event->event_id.header.size = header_size; | |
e4222673 HB |
7299 | } |
7300 | ||
7301 | static void perf_fill_ns_link_info(struct perf_ns_link_info *ns_link_info, | |
7302 | struct task_struct *task, | |
7303 | const struct proc_ns_operations *ns_ops) | |
7304 | { | |
7305 | struct path ns_path; | |
7306 | struct inode *ns_inode; | |
7307 | void *error; | |
7308 | ||
7309 | error = ns_get_path(&ns_path, task, ns_ops); | |
7310 | if (!error) { | |
7311 | ns_inode = ns_path.dentry->d_inode; | |
7312 | ns_link_info->dev = new_encode_dev(ns_inode->i_sb->s_dev); | |
7313 | ns_link_info->ino = ns_inode->i_ino; | |
0e18dd12 | 7314 | path_put(&ns_path); |
e4222673 HB |
7315 | } |
7316 | } | |
7317 | ||
7318 | void perf_event_namespaces(struct task_struct *task) | |
7319 | { | |
7320 | struct perf_namespaces_event namespaces_event; | |
7321 | struct perf_ns_link_info *ns_link_info; | |
7322 | ||
7323 | if (!atomic_read(&nr_namespaces_events)) | |
7324 | return; | |
7325 | ||
7326 | namespaces_event = (struct perf_namespaces_event){ | |
7327 | .task = task, | |
7328 | .event_id = { | |
7329 | .header = { | |
7330 | .type = PERF_RECORD_NAMESPACES, | |
7331 | .misc = 0, | |
7332 | .size = sizeof(namespaces_event.event_id), | |
7333 | }, | |
7334 | /* .pid */ | |
7335 | /* .tid */ | |
7336 | .nr_namespaces = NR_NAMESPACES, | |
7337 | /* .link_info[NR_NAMESPACES] */ | |
7338 | }, | |
7339 | }; | |
7340 | ||
7341 | ns_link_info = namespaces_event.event_id.link_info; | |
7342 | ||
7343 | perf_fill_ns_link_info(&ns_link_info[MNT_NS_INDEX], | |
7344 | task, &mntns_operations); | |
7345 | ||
7346 | #ifdef CONFIG_USER_NS | |
7347 | perf_fill_ns_link_info(&ns_link_info[USER_NS_INDEX], | |
7348 | task, &userns_operations); | |
7349 | #endif | |
7350 | #ifdef CONFIG_NET_NS | |
7351 | perf_fill_ns_link_info(&ns_link_info[NET_NS_INDEX], | |
7352 | task, &netns_operations); | |
7353 | #endif | |
7354 | #ifdef CONFIG_UTS_NS | |
7355 | perf_fill_ns_link_info(&ns_link_info[UTS_NS_INDEX], | |
7356 | task, &utsns_operations); | |
7357 | #endif | |
7358 | #ifdef CONFIG_IPC_NS | |
7359 | perf_fill_ns_link_info(&ns_link_info[IPC_NS_INDEX], | |
7360 | task, &ipcns_operations); | |
7361 | #endif | |
7362 | #ifdef CONFIG_PID_NS | |
7363 | perf_fill_ns_link_info(&ns_link_info[PID_NS_INDEX], | |
7364 | task, &pidns_operations); | |
7365 | #endif | |
7366 | #ifdef CONFIG_CGROUPS | |
7367 | perf_fill_ns_link_info(&ns_link_info[CGROUP_NS_INDEX], | |
7368 | task, &cgroupns_operations); | |
7369 | #endif | |
7370 | ||
7371 | perf_iterate_sb(perf_event_namespaces_output, | |
7372 | &namespaces_event, | |
7373 | NULL); | |
7374 | } | |
7375 | ||
0a4a9391 PZ |
7376 | /* |
7377 | * mmap tracking | |
7378 | */ | |
7379 | ||
7380 | struct perf_mmap_event { | |
089dd79d PZ |
7381 | struct vm_area_struct *vma; |
7382 | ||
7383 | const char *file_name; | |
7384 | int file_size; | |
13d7a241 SE |
7385 | int maj, min; |
7386 | u64 ino; | |
7387 | u64 ino_generation; | |
f972eb63 | 7388 | u32 prot, flags; |
0a4a9391 PZ |
7389 | |
7390 | struct { | |
7391 | struct perf_event_header header; | |
7392 | ||
7393 | u32 pid; | |
7394 | u32 tid; | |
7395 | u64 start; | |
7396 | u64 len; | |
7397 | u64 pgoff; | |
cdd6c482 | 7398 | } event_id; |
0a4a9391 PZ |
7399 | }; |
7400 | ||
67516844 JO |
7401 | static int perf_event_mmap_match(struct perf_event *event, |
7402 | void *data) | |
7403 | { | |
7404 | struct perf_mmap_event *mmap_event = data; | |
7405 | struct vm_area_struct *vma = mmap_event->vma; | |
7406 | int executable = vma->vm_flags & VM_EXEC; | |
7407 | ||
7408 | return (!executable && event->attr.mmap_data) || | |
13d7a241 | 7409 | (executable && (event->attr.mmap || event->attr.mmap2)); |
67516844 JO |
7410 | } |
7411 | ||
cdd6c482 | 7412 | static void perf_event_mmap_output(struct perf_event *event, |
52d857a8 | 7413 | void *data) |
0a4a9391 | 7414 | { |
52d857a8 | 7415 | struct perf_mmap_event *mmap_event = data; |
0a4a9391 | 7416 | struct perf_output_handle handle; |
c980d109 | 7417 | struct perf_sample_data sample; |
cdd6c482 | 7418 | int size = mmap_event->event_id.header.size; |
d9c1bb2f | 7419 | u32 type = mmap_event->event_id.header.type; |
c980d109 | 7420 | int ret; |
0a4a9391 | 7421 | |
67516844 JO |
7422 | if (!perf_event_mmap_match(event, data)) |
7423 | return; | |
7424 | ||
13d7a241 SE |
7425 | if (event->attr.mmap2) { |
7426 | mmap_event->event_id.header.type = PERF_RECORD_MMAP2; | |
7427 | mmap_event->event_id.header.size += sizeof(mmap_event->maj); | |
7428 | mmap_event->event_id.header.size += sizeof(mmap_event->min); | |
7429 | mmap_event->event_id.header.size += sizeof(mmap_event->ino); | |
d008d525 | 7430 | mmap_event->event_id.header.size += sizeof(mmap_event->ino_generation); |
f972eb63 PZ |
7431 | mmap_event->event_id.header.size += sizeof(mmap_event->prot); |
7432 | mmap_event->event_id.header.size += sizeof(mmap_event->flags); | |
13d7a241 SE |
7433 | } |
7434 | ||
c980d109 ACM |
7435 | perf_event_header__init_id(&mmap_event->event_id.header, &sample, event); |
7436 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 7437 | mmap_event->event_id.header.size); |
0a4a9391 | 7438 | if (ret) |
c980d109 | 7439 | goto out; |
0a4a9391 | 7440 | |
cdd6c482 IM |
7441 | mmap_event->event_id.pid = perf_event_pid(event, current); |
7442 | mmap_event->event_id.tid = perf_event_tid(event, current); | |
709e50cf | 7443 | |
cdd6c482 | 7444 | perf_output_put(&handle, mmap_event->event_id); |
13d7a241 SE |
7445 | |
7446 | if (event->attr.mmap2) { | |
7447 | perf_output_put(&handle, mmap_event->maj); | |
7448 | perf_output_put(&handle, mmap_event->min); | |
7449 | perf_output_put(&handle, mmap_event->ino); | |
7450 | perf_output_put(&handle, mmap_event->ino_generation); | |
f972eb63 PZ |
7451 | perf_output_put(&handle, mmap_event->prot); |
7452 | perf_output_put(&handle, mmap_event->flags); | |
13d7a241 SE |
7453 | } |
7454 | ||
76369139 | 7455 | __output_copy(&handle, mmap_event->file_name, |
0a4a9391 | 7456 | mmap_event->file_size); |
c980d109 ACM |
7457 | |
7458 | perf_event__output_id_sample(event, &handle, &sample); | |
7459 | ||
78d613eb | 7460 | perf_output_end(&handle); |
c980d109 ACM |
7461 | out: |
7462 | mmap_event->event_id.header.size = size; | |
d9c1bb2f | 7463 | mmap_event->event_id.header.type = type; |
0a4a9391 PZ |
7464 | } |
7465 | ||
cdd6c482 | 7466 | static void perf_event_mmap_event(struct perf_mmap_event *mmap_event) |
0a4a9391 | 7467 | { |
089dd79d PZ |
7468 | struct vm_area_struct *vma = mmap_event->vma; |
7469 | struct file *file = vma->vm_file; | |
13d7a241 SE |
7470 | int maj = 0, min = 0; |
7471 | u64 ino = 0, gen = 0; | |
f972eb63 | 7472 | u32 prot = 0, flags = 0; |
0a4a9391 PZ |
7473 | unsigned int size; |
7474 | char tmp[16]; | |
7475 | char *buf = NULL; | |
2c42cfbf | 7476 | char *name; |
413ee3b4 | 7477 | |
0b3589be PZ |
7478 | if (vma->vm_flags & VM_READ) |
7479 | prot |= PROT_READ; | |
7480 | if (vma->vm_flags & VM_WRITE) | |
7481 | prot |= PROT_WRITE; | |
7482 | if (vma->vm_flags & VM_EXEC) | |
7483 | prot |= PROT_EXEC; | |
7484 | ||
7485 | if (vma->vm_flags & VM_MAYSHARE) | |
7486 | flags = MAP_SHARED; | |
7487 | else | |
7488 | flags = MAP_PRIVATE; | |
7489 | ||
7490 | if (vma->vm_flags & VM_DENYWRITE) | |
7491 | flags |= MAP_DENYWRITE; | |
7492 | if (vma->vm_flags & VM_MAYEXEC) | |
7493 | flags |= MAP_EXECUTABLE; | |
7494 | if (vma->vm_flags & VM_LOCKED) | |
7495 | flags |= MAP_LOCKED; | |
7496 | if (vma->vm_flags & VM_HUGETLB) | |
7497 | flags |= MAP_HUGETLB; | |
7498 | ||
0a4a9391 | 7499 | if (file) { |
13d7a241 SE |
7500 | struct inode *inode; |
7501 | dev_t dev; | |
3ea2f2b9 | 7502 | |
2c42cfbf | 7503 | buf = kmalloc(PATH_MAX, GFP_KERNEL); |
0a4a9391 | 7504 | if (!buf) { |
c7e548b4 ON |
7505 | name = "//enomem"; |
7506 | goto cpy_name; | |
0a4a9391 | 7507 | } |
413ee3b4 | 7508 | /* |
3ea2f2b9 | 7509 | * d_path() works from the end of the rb backwards, so we |
413ee3b4 AB |
7510 | * need to add enough zero bytes after the string to handle |
7511 | * the 64bit alignment we do later. | |
7512 | */ | |
9bf39ab2 | 7513 | name = file_path(file, buf, PATH_MAX - sizeof(u64)); |
0a4a9391 | 7514 | if (IS_ERR(name)) { |
c7e548b4 ON |
7515 | name = "//toolong"; |
7516 | goto cpy_name; | |
0a4a9391 | 7517 | } |
13d7a241 SE |
7518 | inode = file_inode(vma->vm_file); |
7519 | dev = inode->i_sb->s_dev; | |
7520 | ino = inode->i_ino; | |
7521 | gen = inode->i_generation; | |
7522 | maj = MAJOR(dev); | |
7523 | min = MINOR(dev); | |
f972eb63 | 7524 | |
c7e548b4 | 7525 | goto got_name; |
0a4a9391 | 7526 | } else { |
fbe26abe JO |
7527 | if (vma->vm_ops && vma->vm_ops->name) { |
7528 | name = (char *) vma->vm_ops->name(vma); | |
7529 | if (name) | |
7530 | goto cpy_name; | |
7531 | } | |
7532 | ||
2c42cfbf | 7533 | name = (char *)arch_vma_name(vma); |
c7e548b4 ON |
7534 | if (name) |
7535 | goto cpy_name; | |
089dd79d | 7536 | |
32c5fb7e | 7537 | if (vma->vm_start <= vma->vm_mm->start_brk && |
3af9e859 | 7538 | vma->vm_end >= vma->vm_mm->brk) { |
c7e548b4 ON |
7539 | name = "[heap]"; |
7540 | goto cpy_name; | |
32c5fb7e ON |
7541 | } |
7542 | if (vma->vm_start <= vma->vm_mm->start_stack && | |
3af9e859 | 7543 | vma->vm_end >= vma->vm_mm->start_stack) { |
c7e548b4 ON |
7544 | name = "[stack]"; |
7545 | goto cpy_name; | |
089dd79d PZ |
7546 | } |
7547 | ||
c7e548b4 ON |
7548 | name = "//anon"; |
7549 | goto cpy_name; | |
0a4a9391 PZ |
7550 | } |
7551 | ||
c7e548b4 ON |
7552 | cpy_name: |
7553 | strlcpy(tmp, name, sizeof(tmp)); | |
7554 | name = tmp; | |
0a4a9391 | 7555 | got_name: |
2c42cfbf PZ |
7556 | /* |
7557 | * Since our buffer works in 8 byte units we need to align our string | |
7558 | * size to a multiple of 8. However, we must guarantee the tail end is | |
7559 | * zero'd out to avoid leaking random bits to userspace. | |
7560 | */ | |
7561 | size = strlen(name)+1; | |
7562 | while (!IS_ALIGNED(size, sizeof(u64))) | |
7563 | name[size++] = '\0'; | |
0a4a9391 PZ |
7564 | |
7565 | mmap_event->file_name = name; | |
7566 | mmap_event->file_size = size; | |
13d7a241 SE |
7567 | mmap_event->maj = maj; |
7568 | mmap_event->min = min; | |
7569 | mmap_event->ino = ino; | |
7570 | mmap_event->ino_generation = gen; | |
f972eb63 PZ |
7571 | mmap_event->prot = prot; |
7572 | mmap_event->flags = flags; | |
0a4a9391 | 7573 | |
2fe85427 SE |
7574 | if (!(vma->vm_flags & VM_EXEC)) |
7575 | mmap_event->event_id.header.misc |= PERF_RECORD_MISC_MMAP_DATA; | |
7576 | ||
cdd6c482 | 7577 | mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size; |
0a4a9391 | 7578 | |
aab5b71e | 7579 | perf_iterate_sb(perf_event_mmap_output, |
52d857a8 JO |
7580 | mmap_event, |
7581 | NULL); | |
665c2142 | 7582 | |
0a4a9391 PZ |
7583 | kfree(buf); |
7584 | } | |
7585 | ||
375637bc AS |
7586 | /* |
7587 | * Check whether inode and address range match filter criteria. | |
7588 | */ | |
7589 | static bool perf_addr_filter_match(struct perf_addr_filter *filter, | |
7590 | struct file *file, unsigned long offset, | |
7591 | unsigned long size) | |
7592 | { | |
7f635ff1 MP |
7593 | /* d_inode(NULL) won't be equal to any mapped user-space file */ |
7594 | if (!filter->path.dentry) | |
7595 | return false; | |
7596 | ||
9511bce9 | 7597 | if (d_inode(filter->path.dentry) != file_inode(file)) |
375637bc AS |
7598 | return false; |
7599 | ||
7600 | if (filter->offset > offset + size) | |
7601 | return false; | |
7602 | ||
7603 | if (filter->offset + filter->size < offset) | |
7604 | return false; | |
7605 | ||
7606 | return true; | |
7607 | } | |
7608 | ||
c60f83b8 AS |
7609 | static bool perf_addr_filter_vma_adjust(struct perf_addr_filter *filter, |
7610 | struct vm_area_struct *vma, | |
7611 | struct perf_addr_filter_range *fr) | |
7612 | { | |
7613 | unsigned long vma_size = vma->vm_end - vma->vm_start; | |
7614 | unsigned long off = vma->vm_pgoff << PAGE_SHIFT; | |
7615 | struct file *file = vma->vm_file; | |
7616 | ||
7617 | if (!perf_addr_filter_match(filter, file, off, vma_size)) | |
7618 | return false; | |
7619 | ||
7620 | if (filter->offset < off) { | |
7621 | fr->start = vma->vm_start; | |
7622 | fr->size = min(vma_size, filter->size - (off - filter->offset)); | |
7623 | } else { | |
7624 | fr->start = vma->vm_start + filter->offset - off; | |
7625 | fr->size = min(vma->vm_end - fr->start, filter->size); | |
7626 | } | |
7627 | ||
7628 | return true; | |
7629 | } | |
7630 | ||
375637bc AS |
7631 | static void __perf_addr_filters_adjust(struct perf_event *event, void *data) |
7632 | { | |
7633 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
7634 | struct vm_area_struct *vma = data; | |
375637bc AS |
7635 | struct perf_addr_filter *filter; |
7636 | unsigned int restart = 0, count = 0; | |
c60f83b8 | 7637 | unsigned long flags; |
375637bc AS |
7638 | |
7639 | if (!has_addr_filter(event)) | |
7640 | return; | |
7641 | ||
c60f83b8 | 7642 | if (!vma->vm_file) |
375637bc AS |
7643 | return; |
7644 | ||
7645 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
7646 | list_for_each_entry(filter, &ifh->list, entry) { | |
c60f83b8 AS |
7647 | if (perf_addr_filter_vma_adjust(filter, vma, |
7648 | &event->addr_filter_ranges[count])) | |
375637bc | 7649 | restart++; |
375637bc AS |
7650 | |
7651 | count++; | |
7652 | } | |
7653 | ||
7654 | if (restart) | |
7655 | event->addr_filters_gen++; | |
7656 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
7657 | ||
7658 | if (restart) | |
767ae086 | 7659 | perf_event_stop(event, 1); |
375637bc AS |
7660 | } |
7661 | ||
7662 | /* | |
7663 | * Adjust all task's events' filters to the new vma | |
7664 | */ | |
7665 | static void perf_addr_filters_adjust(struct vm_area_struct *vma) | |
7666 | { | |
7667 | struct perf_event_context *ctx; | |
7668 | int ctxn; | |
7669 | ||
12b40a23 MP |
7670 | /* |
7671 | * Data tracing isn't supported yet and as such there is no need | |
7672 | * to keep track of anything that isn't related to executable code: | |
7673 | */ | |
7674 | if (!(vma->vm_flags & VM_EXEC)) | |
7675 | return; | |
7676 | ||
375637bc AS |
7677 | rcu_read_lock(); |
7678 | for_each_task_context_nr(ctxn) { | |
7679 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); | |
7680 | if (!ctx) | |
7681 | continue; | |
7682 | ||
aab5b71e | 7683 | perf_iterate_ctx(ctx, __perf_addr_filters_adjust, vma, true); |
375637bc AS |
7684 | } |
7685 | rcu_read_unlock(); | |
7686 | } | |
7687 | ||
3af9e859 | 7688 | void perf_event_mmap(struct vm_area_struct *vma) |
0a4a9391 | 7689 | { |
9ee318a7 PZ |
7690 | struct perf_mmap_event mmap_event; |
7691 | ||
cdd6c482 | 7692 | if (!atomic_read(&nr_mmap_events)) |
9ee318a7 PZ |
7693 | return; |
7694 | ||
7695 | mmap_event = (struct perf_mmap_event){ | |
089dd79d | 7696 | .vma = vma, |
573402db PZ |
7697 | /* .file_name */ |
7698 | /* .file_size */ | |
cdd6c482 | 7699 | .event_id = { |
573402db | 7700 | .header = { |
cdd6c482 | 7701 | .type = PERF_RECORD_MMAP, |
39447b38 | 7702 | .misc = PERF_RECORD_MISC_USER, |
573402db PZ |
7703 | /* .size */ |
7704 | }, | |
7705 | /* .pid */ | |
7706 | /* .tid */ | |
089dd79d PZ |
7707 | .start = vma->vm_start, |
7708 | .len = vma->vm_end - vma->vm_start, | |
3a0304e9 | 7709 | .pgoff = (u64)vma->vm_pgoff << PAGE_SHIFT, |
0a4a9391 | 7710 | }, |
13d7a241 SE |
7711 | /* .maj (attr_mmap2 only) */ |
7712 | /* .min (attr_mmap2 only) */ | |
7713 | /* .ino (attr_mmap2 only) */ | |
7714 | /* .ino_generation (attr_mmap2 only) */ | |
f972eb63 PZ |
7715 | /* .prot (attr_mmap2 only) */ |
7716 | /* .flags (attr_mmap2 only) */ | |
0a4a9391 PZ |
7717 | }; |
7718 | ||
375637bc | 7719 | perf_addr_filters_adjust(vma); |
cdd6c482 | 7720 | perf_event_mmap_event(&mmap_event); |
0a4a9391 PZ |
7721 | } |
7722 | ||
68db7e98 AS |
7723 | void perf_event_aux_event(struct perf_event *event, unsigned long head, |
7724 | unsigned long size, u64 flags) | |
7725 | { | |
7726 | struct perf_output_handle handle; | |
7727 | struct perf_sample_data sample; | |
7728 | struct perf_aux_event { | |
7729 | struct perf_event_header header; | |
7730 | u64 offset; | |
7731 | u64 size; | |
7732 | u64 flags; | |
7733 | } rec = { | |
7734 | .header = { | |
7735 | .type = PERF_RECORD_AUX, | |
7736 | .misc = 0, | |
7737 | .size = sizeof(rec), | |
7738 | }, | |
7739 | .offset = head, | |
7740 | .size = size, | |
7741 | .flags = flags, | |
7742 | }; | |
7743 | int ret; | |
7744 | ||
7745 | perf_event_header__init_id(&rec.header, &sample, event); | |
7746 | ret = perf_output_begin(&handle, event, rec.header.size); | |
7747 | ||
7748 | if (ret) | |
7749 | return; | |
7750 | ||
7751 | perf_output_put(&handle, rec); | |
7752 | perf_event__output_id_sample(event, &handle, &sample); | |
7753 | ||
7754 | perf_output_end(&handle); | |
7755 | } | |
7756 | ||
f38b0dbb KL |
7757 | /* |
7758 | * Lost/dropped samples logging | |
7759 | */ | |
7760 | void perf_log_lost_samples(struct perf_event *event, u64 lost) | |
7761 | { | |
7762 | struct perf_output_handle handle; | |
7763 | struct perf_sample_data sample; | |
7764 | int ret; | |
7765 | ||
7766 | struct { | |
7767 | struct perf_event_header header; | |
7768 | u64 lost; | |
7769 | } lost_samples_event = { | |
7770 | .header = { | |
7771 | .type = PERF_RECORD_LOST_SAMPLES, | |
7772 | .misc = 0, | |
7773 | .size = sizeof(lost_samples_event), | |
7774 | }, | |
7775 | .lost = lost, | |
7776 | }; | |
7777 | ||
7778 | perf_event_header__init_id(&lost_samples_event.header, &sample, event); | |
7779 | ||
7780 | ret = perf_output_begin(&handle, event, | |
7781 | lost_samples_event.header.size); | |
7782 | if (ret) | |
7783 | return; | |
7784 | ||
7785 | perf_output_put(&handle, lost_samples_event); | |
7786 | perf_event__output_id_sample(event, &handle, &sample); | |
7787 | perf_output_end(&handle); | |
7788 | } | |
7789 | ||
45ac1403 AH |
7790 | /* |
7791 | * context_switch tracking | |
7792 | */ | |
7793 | ||
7794 | struct perf_switch_event { | |
7795 | struct task_struct *task; | |
7796 | struct task_struct *next_prev; | |
7797 | ||
7798 | struct { | |
7799 | struct perf_event_header header; | |
7800 | u32 next_prev_pid; | |
7801 | u32 next_prev_tid; | |
7802 | } event_id; | |
7803 | }; | |
7804 | ||
7805 | static int perf_event_switch_match(struct perf_event *event) | |
7806 | { | |
7807 | return event->attr.context_switch; | |
7808 | } | |
7809 | ||
7810 | static void perf_event_switch_output(struct perf_event *event, void *data) | |
7811 | { | |
7812 | struct perf_switch_event *se = data; | |
7813 | struct perf_output_handle handle; | |
7814 | struct perf_sample_data sample; | |
7815 | int ret; | |
7816 | ||
7817 | if (!perf_event_switch_match(event)) | |
7818 | return; | |
7819 | ||
7820 | /* Only CPU-wide events are allowed to see next/prev pid/tid */ | |
7821 | if (event->ctx->task) { | |
7822 | se->event_id.header.type = PERF_RECORD_SWITCH; | |
7823 | se->event_id.header.size = sizeof(se->event_id.header); | |
7824 | } else { | |
7825 | se->event_id.header.type = PERF_RECORD_SWITCH_CPU_WIDE; | |
7826 | se->event_id.header.size = sizeof(se->event_id); | |
7827 | se->event_id.next_prev_pid = | |
7828 | perf_event_pid(event, se->next_prev); | |
7829 | se->event_id.next_prev_tid = | |
7830 | perf_event_tid(event, se->next_prev); | |
7831 | } | |
7832 | ||
7833 | perf_event_header__init_id(&se->event_id.header, &sample, event); | |
7834 | ||
7835 | ret = perf_output_begin(&handle, event, se->event_id.header.size); | |
7836 | if (ret) | |
7837 | return; | |
7838 | ||
7839 | if (event->ctx->task) | |
7840 | perf_output_put(&handle, se->event_id.header); | |
7841 | else | |
7842 | perf_output_put(&handle, se->event_id); | |
7843 | ||
7844 | perf_event__output_id_sample(event, &handle, &sample); | |
7845 | ||
7846 | perf_output_end(&handle); | |
7847 | } | |
7848 | ||
7849 | static void perf_event_switch(struct task_struct *task, | |
7850 | struct task_struct *next_prev, bool sched_in) | |
7851 | { | |
7852 | struct perf_switch_event switch_event; | |
7853 | ||
7854 | /* N.B. caller checks nr_switch_events != 0 */ | |
7855 | ||
7856 | switch_event = (struct perf_switch_event){ | |
7857 | .task = task, | |
7858 | .next_prev = next_prev, | |
7859 | .event_id = { | |
7860 | .header = { | |
7861 | /* .type */ | |
7862 | .misc = sched_in ? 0 : PERF_RECORD_MISC_SWITCH_OUT, | |
7863 | /* .size */ | |
7864 | }, | |
7865 | /* .next_prev_pid */ | |
7866 | /* .next_prev_tid */ | |
7867 | }, | |
7868 | }; | |
7869 | ||
101592b4 AB |
7870 | if (!sched_in && task->state == TASK_RUNNING) |
7871 | switch_event.event_id.header.misc |= | |
7872 | PERF_RECORD_MISC_SWITCH_OUT_PREEMPT; | |
7873 | ||
aab5b71e | 7874 | perf_iterate_sb(perf_event_switch_output, |
45ac1403 AH |
7875 | &switch_event, |
7876 | NULL); | |
7877 | } | |
7878 | ||
a78ac325 PZ |
7879 | /* |
7880 | * IRQ throttle logging | |
7881 | */ | |
7882 | ||
cdd6c482 | 7883 | static void perf_log_throttle(struct perf_event *event, int enable) |
a78ac325 PZ |
7884 | { |
7885 | struct perf_output_handle handle; | |
c980d109 | 7886 | struct perf_sample_data sample; |
a78ac325 PZ |
7887 | int ret; |
7888 | ||
7889 | struct { | |
7890 | struct perf_event_header header; | |
7891 | u64 time; | |
cca3f454 | 7892 | u64 id; |
7f453c24 | 7893 | u64 stream_id; |
a78ac325 PZ |
7894 | } throttle_event = { |
7895 | .header = { | |
cdd6c482 | 7896 | .type = PERF_RECORD_THROTTLE, |
a78ac325 PZ |
7897 | .misc = 0, |
7898 | .size = sizeof(throttle_event), | |
7899 | }, | |
34f43927 | 7900 | .time = perf_event_clock(event), |
cdd6c482 IM |
7901 | .id = primary_event_id(event), |
7902 | .stream_id = event->id, | |
a78ac325 PZ |
7903 | }; |
7904 | ||
966ee4d6 | 7905 | if (enable) |
cdd6c482 | 7906 | throttle_event.header.type = PERF_RECORD_UNTHROTTLE; |
966ee4d6 | 7907 | |
c980d109 ACM |
7908 | perf_event_header__init_id(&throttle_event.header, &sample, event); |
7909 | ||
7910 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 7911 | throttle_event.header.size); |
a78ac325 PZ |
7912 | if (ret) |
7913 | return; | |
7914 | ||
7915 | perf_output_put(&handle, throttle_event); | |
c980d109 | 7916 | perf_event__output_id_sample(event, &handle, &sample); |
a78ac325 PZ |
7917 | perf_output_end(&handle); |
7918 | } | |
7919 | ||
76193a94 SL |
7920 | /* |
7921 | * ksymbol register/unregister tracking | |
7922 | */ | |
7923 | ||
7924 | struct perf_ksymbol_event { | |
7925 | const char *name; | |
7926 | int name_len; | |
7927 | struct { | |
7928 | struct perf_event_header header; | |
7929 | u64 addr; | |
7930 | u32 len; | |
7931 | u16 ksym_type; | |
7932 | u16 flags; | |
7933 | } event_id; | |
7934 | }; | |
7935 | ||
7936 | static int perf_event_ksymbol_match(struct perf_event *event) | |
7937 | { | |
7938 | return event->attr.ksymbol; | |
7939 | } | |
7940 | ||
7941 | static void perf_event_ksymbol_output(struct perf_event *event, void *data) | |
7942 | { | |
7943 | struct perf_ksymbol_event *ksymbol_event = data; | |
7944 | struct perf_output_handle handle; | |
7945 | struct perf_sample_data sample; | |
7946 | int ret; | |
7947 | ||
7948 | if (!perf_event_ksymbol_match(event)) | |
7949 | return; | |
7950 | ||
7951 | perf_event_header__init_id(&ksymbol_event->event_id.header, | |
7952 | &sample, event); | |
7953 | ret = perf_output_begin(&handle, event, | |
7954 | ksymbol_event->event_id.header.size); | |
7955 | if (ret) | |
7956 | return; | |
7957 | ||
7958 | perf_output_put(&handle, ksymbol_event->event_id); | |
7959 | __output_copy(&handle, ksymbol_event->name, ksymbol_event->name_len); | |
7960 | perf_event__output_id_sample(event, &handle, &sample); | |
7961 | ||
7962 | perf_output_end(&handle); | |
7963 | } | |
7964 | ||
7965 | void perf_event_ksymbol(u16 ksym_type, u64 addr, u32 len, bool unregister, | |
7966 | const char *sym) | |
7967 | { | |
7968 | struct perf_ksymbol_event ksymbol_event; | |
7969 | char name[KSYM_NAME_LEN]; | |
7970 | u16 flags = 0; | |
7971 | int name_len; | |
7972 | ||
7973 | if (!atomic_read(&nr_ksymbol_events)) | |
7974 | return; | |
7975 | ||
7976 | if (ksym_type >= PERF_RECORD_KSYMBOL_TYPE_MAX || | |
7977 | ksym_type == PERF_RECORD_KSYMBOL_TYPE_UNKNOWN) | |
7978 | goto err; | |
7979 | ||
7980 | strlcpy(name, sym, KSYM_NAME_LEN); | |
7981 | name_len = strlen(name) + 1; | |
7982 | while (!IS_ALIGNED(name_len, sizeof(u64))) | |
7983 | name[name_len++] = '\0'; | |
7984 | BUILD_BUG_ON(KSYM_NAME_LEN % sizeof(u64)); | |
7985 | ||
7986 | if (unregister) | |
7987 | flags |= PERF_RECORD_KSYMBOL_FLAGS_UNREGISTER; | |
7988 | ||
7989 | ksymbol_event = (struct perf_ksymbol_event){ | |
7990 | .name = name, | |
7991 | .name_len = name_len, | |
7992 | .event_id = { | |
7993 | .header = { | |
7994 | .type = PERF_RECORD_KSYMBOL, | |
7995 | .size = sizeof(ksymbol_event.event_id) + | |
7996 | name_len, | |
7997 | }, | |
7998 | .addr = addr, | |
7999 | .len = len, | |
8000 | .ksym_type = ksym_type, | |
8001 | .flags = flags, | |
8002 | }, | |
8003 | }; | |
8004 | ||
8005 | perf_iterate_sb(perf_event_ksymbol_output, &ksymbol_event, NULL); | |
8006 | return; | |
8007 | err: | |
8008 | WARN_ONCE(1, "%s: Invalid KSYMBOL type 0x%x\n", __func__, ksym_type); | |
8009 | } | |
8010 | ||
6ee52e2a SL |
8011 | /* |
8012 | * bpf program load/unload tracking | |
8013 | */ | |
8014 | ||
8015 | struct perf_bpf_event { | |
8016 | struct bpf_prog *prog; | |
8017 | struct { | |
8018 | struct perf_event_header header; | |
8019 | u16 type; | |
8020 | u16 flags; | |
8021 | u32 id; | |
8022 | u8 tag[BPF_TAG_SIZE]; | |
8023 | } event_id; | |
8024 | }; | |
8025 | ||
8026 | static int perf_event_bpf_match(struct perf_event *event) | |
8027 | { | |
8028 | return event->attr.bpf_event; | |
8029 | } | |
8030 | ||
8031 | static void perf_event_bpf_output(struct perf_event *event, void *data) | |
8032 | { | |
8033 | struct perf_bpf_event *bpf_event = data; | |
8034 | struct perf_output_handle handle; | |
8035 | struct perf_sample_data sample; | |
8036 | int ret; | |
8037 | ||
8038 | if (!perf_event_bpf_match(event)) | |
8039 | return; | |
8040 | ||
8041 | perf_event_header__init_id(&bpf_event->event_id.header, | |
8042 | &sample, event); | |
8043 | ret = perf_output_begin(&handle, event, | |
8044 | bpf_event->event_id.header.size); | |
8045 | if (ret) | |
8046 | return; | |
8047 | ||
8048 | perf_output_put(&handle, bpf_event->event_id); | |
8049 | perf_event__output_id_sample(event, &handle, &sample); | |
8050 | ||
8051 | perf_output_end(&handle); | |
8052 | } | |
8053 | ||
8054 | static void perf_event_bpf_emit_ksymbols(struct bpf_prog *prog, | |
8055 | enum perf_bpf_event_type type) | |
8056 | { | |
8057 | bool unregister = type == PERF_BPF_EVENT_PROG_UNLOAD; | |
8058 | char sym[KSYM_NAME_LEN]; | |
8059 | int i; | |
8060 | ||
8061 | if (prog->aux->func_cnt == 0) { | |
8062 | bpf_get_prog_name(prog, sym); | |
8063 | perf_event_ksymbol(PERF_RECORD_KSYMBOL_TYPE_BPF, | |
8064 | (u64)(unsigned long)prog->bpf_func, | |
8065 | prog->jited_len, unregister, sym); | |
8066 | } else { | |
8067 | for (i = 0; i < prog->aux->func_cnt; i++) { | |
8068 | struct bpf_prog *subprog = prog->aux->func[i]; | |
8069 | ||
8070 | bpf_get_prog_name(subprog, sym); | |
8071 | perf_event_ksymbol( | |
8072 | PERF_RECORD_KSYMBOL_TYPE_BPF, | |
8073 | (u64)(unsigned long)subprog->bpf_func, | |
8074 | subprog->jited_len, unregister, sym); | |
8075 | } | |
8076 | } | |
8077 | } | |
8078 | ||
8079 | void perf_event_bpf_event(struct bpf_prog *prog, | |
8080 | enum perf_bpf_event_type type, | |
8081 | u16 flags) | |
8082 | { | |
8083 | struct perf_bpf_event bpf_event; | |
8084 | ||
8085 | if (type <= PERF_BPF_EVENT_UNKNOWN || | |
8086 | type >= PERF_BPF_EVENT_MAX) | |
8087 | return; | |
8088 | ||
8089 | switch (type) { | |
8090 | case PERF_BPF_EVENT_PROG_LOAD: | |
8091 | case PERF_BPF_EVENT_PROG_UNLOAD: | |
8092 | if (atomic_read(&nr_ksymbol_events)) | |
8093 | perf_event_bpf_emit_ksymbols(prog, type); | |
8094 | break; | |
8095 | default: | |
8096 | break; | |
8097 | } | |
8098 | ||
8099 | if (!atomic_read(&nr_bpf_events)) | |
8100 | return; | |
8101 | ||
8102 | bpf_event = (struct perf_bpf_event){ | |
8103 | .prog = prog, | |
8104 | .event_id = { | |
8105 | .header = { | |
8106 | .type = PERF_RECORD_BPF_EVENT, | |
8107 | .size = sizeof(bpf_event.event_id), | |
8108 | }, | |
8109 | .type = type, | |
8110 | .flags = flags, | |
8111 | .id = prog->aux->id, | |
8112 | }, | |
8113 | }; | |
8114 | ||
8115 | BUILD_BUG_ON(BPF_TAG_SIZE % sizeof(u64)); | |
8116 | ||
8117 | memcpy(bpf_event.event_id.tag, prog->tag, BPF_TAG_SIZE); | |
8118 | perf_iterate_sb(perf_event_bpf_output, &bpf_event, NULL); | |
8119 | } | |
8120 | ||
8d4e6c4c AS |
8121 | void perf_event_itrace_started(struct perf_event *event) |
8122 | { | |
8123 | event->attach_state |= PERF_ATTACH_ITRACE; | |
8124 | } | |
8125 | ||
ec0d7729 AS |
8126 | static void perf_log_itrace_start(struct perf_event *event) |
8127 | { | |
8128 | struct perf_output_handle handle; | |
8129 | struct perf_sample_data sample; | |
8130 | struct perf_aux_event { | |
8131 | struct perf_event_header header; | |
8132 | u32 pid; | |
8133 | u32 tid; | |
8134 | } rec; | |
8135 | int ret; | |
8136 | ||
8137 | if (event->parent) | |
8138 | event = event->parent; | |
8139 | ||
8140 | if (!(event->pmu->capabilities & PERF_PMU_CAP_ITRACE) || | |
8d4e6c4c | 8141 | event->attach_state & PERF_ATTACH_ITRACE) |
ec0d7729 AS |
8142 | return; |
8143 | ||
ec0d7729 AS |
8144 | rec.header.type = PERF_RECORD_ITRACE_START; |
8145 | rec.header.misc = 0; | |
8146 | rec.header.size = sizeof(rec); | |
8147 | rec.pid = perf_event_pid(event, current); | |
8148 | rec.tid = perf_event_tid(event, current); | |
8149 | ||
8150 | perf_event_header__init_id(&rec.header, &sample, event); | |
8151 | ret = perf_output_begin(&handle, event, rec.header.size); | |
8152 | ||
8153 | if (ret) | |
8154 | return; | |
8155 | ||
8156 | perf_output_put(&handle, rec); | |
8157 | perf_event__output_id_sample(event, &handle, &sample); | |
8158 | ||
8159 | perf_output_end(&handle); | |
8160 | } | |
8161 | ||
475113d9 JO |
8162 | static int |
8163 | __perf_event_account_interrupt(struct perf_event *event, int throttle) | |
f6c7d5fe | 8164 | { |
cdd6c482 | 8165 | struct hw_perf_event *hwc = &event->hw; |
79f14641 | 8166 | int ret = 0; |
475113d9 | 8167 | u64 seq; |
96398826 | 8168 | |
e050e3f0 SE |
8169 | seq = __this_cpu_read(perf_throttled_seq); |
8170 | if (seq != hwc->interrupts_seq) { | |
8171 | hwc->interrupts_seq = seq; | |
8172 | hwc->interrupts = 1; | |
8173 | } else { | |
8174 | hwc->interrupts++; | |
8175 | if (unlikely(throttle | |
8176 | && hwc->interrupts >= max_samples_per_tick)) { | |
8177 | __this_cpu_inc(perf_throttled_count); | |
555e0c1e | 8178 | tick_dep_set_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
163ec435 PZ |
8179 | hwc->interrupts = MAX_INTERRUPTS; |
8180 | perf_log_throttle(event, 0); | |
a78ac325 PZ |
8181 | ret = 1; |
8182 | } | |
e050e3f0 | 8183 | } |
60db5e09 | 8184 | |
cdd6c482 | 8185 | if (event->attr.freq) { |
def0a9b2 | 8186 | u64 now = perf_clock(); |
abd50713 | 8187 | s64 delta = now - hwc->freq_time_stamp; |
bd2b5b12 | 8188 | |
abd50713 | 8189 | hwc->freq_time_stamp = now; |
bd2b5b12 | 8190 | |
abd50713 | 8191 | if (delta > 0 && delta < 2*TICK_NSEC) |
f39d47ff | 8192 | perf_adjust_period(event, delta, hwc->last_period, true); |
bd2b5b12 PZ |
8193 | } |
8194 | ||
475113d9 JO |
8195 | return ret; |
8196 | } | |
8197 | ||
8198 | int perf_event_account_interrupt(struct perf_event *event) | |
8199 | { | |
8200 | return __perf_event_account_interrupt(event, 1); | |
8201 | } | |
8202 | ||
8203 | /* | |
8204 | * Generic event overflow handling, sampling. | |
8205 | */ | |
8206 | ||
8207 | static int __perf_event_overflow(struct perf_event *event, | |
8208 | int throttle, struct perf_sample_data *data, | |
8209 | struct pt_regs *regs) | |
8210 | { | |
8211 | int events = atomic_read(&event->event_limit); | |
8212 | int ret = 0; | |
8213 | ||
8214 | /* | |
8215 | * Non-sampling counters might still use the PMI to fold short | |
8216 | * hardware counters, ignore those. | |
8217 | */ | |
8218 | if (unlikely(!is_sampling_event(event))) | |
8219 | return 0; | |
8220 | ||
8221 | ret = __perf_event_account_interrupt(event, throttle); | |
cc1582c2 | 8222 | |
2023b359 PZ |
8223 | /* |
8224 | * XXX event_limit might not quite work as expected on inherited | |
cdd6c482 | 8225 | * events |
2023b359 PZ |
8226 | */ |
8227 | ||
cdd6c482 IM |
8228 | event->pending_kill = POLL_IN; |
8229 | if (events && atomic_dec_and_test(&event->event_limit)) { | |
79f14641 | 8230 | ret = 1; |
cdd6c482 | 8231 | event->pending_kill = POLL_HUP; |
5aab90ce JO |
8232 | |
8233 | perf_event_disable_inatomic(event); | |
79f14641 PZ |
8234 | } |
8235 | ||
aa6a5f3c | 8236 | READ_ONCE(event->overflow_handler)(event, data, regs); |
453f19ee | 8237 | |
fed66e2c | 8238 | if (*perf_event_fasync(event) && event->pending_kill) { |
a8b0ca17 PZ |
8239 | event->pending_wakeup = 1; |
8240 | irq_work_queue(&event->pending); | |
f506b3dc PZ |
8241 | } |
8242 | ||
79f14641 | 8243 | return ret; |
f6c7d5fe PZ |
8244 | } |
8245 | ||
a8b0ca17 | 8246 | int perf_event_overflow(struct perf_event *event, |
5622f295 MM |
8247 | struct perf_sample_data *data, |
8248 | struct pt_regs *regs) | |
850bc73f | 8249 | { |
a8b0ca17 | 8250 | return __perf_event_overflow(event, 1, data, regs); |
850bc73f PZ |
8251 | } |
8252 | ||
15dbf27c | 8253 | /* |
cdd6c482 | 8254 | * Generic software event infrastructure |
15dbf27c PZ |
8255 | */ |
8256 | ||
b28ab83c PZ |
8257 | struct swevent_htable { |
8258 | struct swevent_hlist *swevent_hlist; | |
8259 | struct mutex hlist_mutex; | |
8260 | int hlist_refcount; | |
8261 | ||
8262 | /* Recursion avoidance in each contexts */ | |
8263 | int recursion[PERF_NR_CONTEXTS]; | |
8264 | }; | |
8265 | ||
8266 | static DEFINE_PER_CPU(struct swevent_htable, swevent_htable); | |
8267 | ||
7b4b6658 | 8268 | /* |
cdd6c482 IM |
8269 | * We directly increment event->count and keep a second value in |
8270 | * event->hw.period_left to count intervals. This period event | |
7b4b6658 PZ |
8271 | * is kept in the range [-sample_period, 0] so that we can use the |
8272 | * sign as trigger. | |
8273 | */ | |
8274 | ||
ab573844 | 8275 | u64 perf_swevent_set_period(struct perf_event *event) |
15dbf27c | 8276 | { |
cdd6c482 | 8277 | struct hw_perf_event *hwc = &event->hw; |
7b4b6658 PZ |
8278 | u64 period = hwc->last_period; |
8279 | u64 nr, offset; | |
8280 | s64 old, val; | |
8281 | ||
8282 | hwc->last_period = hwc->sample_period; | |
15dbf27c PZ |
8283 | |
8284 | again: | |
e7850595 | 8285 | old = val = local64_read(&hwc->period_left); |
7b4b6658 PZ |
8286 | if (val < 0) |
8287 | return 0; | |
15dbf27c | 8288 | |
7b4b6658 PZ |
8289 | nr = div64_u64(period + val, period); |
8290 | offset = nr * period; | |
8291 | val -= offset; | |
e7850595 | 8292 | if (local64_cmpxchg(&hwc->period_left, old, val) != old) |
7b4b6658 | 8293 | goto again; |
15dbf27c | 8294 | |
7b4b6658 | 8295 | return nr; |
15dbf27c PZ |
8296 | } |
8297 | ||
0cff784a | 8298 | static void perf_swevent_overflow(struct perf_event *event, u64 overflow, |
a8b0ca17 | 8299 | struct perf_sample_data *data, |
5622f295 | 8300 | struct pt_regs *regs) |
15dbf27c | 8301 | { |
cdd6c482 | 8302 | struct hw_perf_event *hwc = &event->hw; |
850bc73f | 8303 | int throttle = 0; |
15dbf27c | 8304 | |
0cff784a PZ |
8305 | if (!overflow) |
8306 | overflow = perf_swevent_set_period(event); | |
15dbf27c | 8307 | |
7b4b6658 PZ |
8308 | if (hwc->interrupts == MAX_INTERRUPTS) |
8309 | return; | |
15dbf27c | 8310 | |
7b4b6658 | 8311 | for (; overflow; overflow--) { |
a8b0ca17 | 8312 | if (__perf_event_overflow(event, throttle, |
5622f295 | 8313 | data, regs)) { |
7b4b6658 PZ |
8314 | /* |
8315 | * We inhibit the overflow from happening when | |
8316 | * hwc->interrupts == MAX_INTERRUPTS. | |
8317 | */ | |
8318 | break; | |
8319 | } | |
cf450a73 | 8320 | throttle = 1; |
7b4b6658 | 8321 | } |
15dbf27c PZ |
8322 | } |
8323 | ||
a4eaf7f1 | 8324 | static void perf_swevent_event(struct perf_event *event, u64 nr, |
a8b0ca17 | 8325 | struct perf_sample_data *data, |
5622f295 | 8326 | struct pt_regs *regs) |
7b4b6658 | 8327 | { |
cdd6c482 | 8328 | struct hw_perf_event *hwc = &event->hw; |
d6d020e9 | 8329 | |
e7850595 | 8330 | local64_add(nr, &event->count); |
d6d020e9 | 8331 | |
0cff784a PZ |
8332 | if (!regs) |
8333 | return; | |
8334 | ||
6c7e550f | 8335 | if (!is_sampling_event(event)) |
7b4b6658 | 8336 | return; |
d6d020e9 | 8337 | |
5d81e5cf AV |
8338 | if ((event->attr.sample_type & PERF_SAMPLE_PERIOD) && !event->attr.freq) { |
8339 | data->period = nr; | |
8340 | return perf_swevent_overflow(event, 1, data, regs); | |
8341 | } else | |
8342 | data->period = event->hw.last_period; | |
8343 | ||
0cff784a | 8344 | if (nr == 1 && hwc->sample_period == 1 && !event->attr.freq) |
a8b0ca17 | 8345 | return perf_swevent_overflow(event, 1, data, regs); |
0cff784a | 8346 | |
e7850595 | 8347 | if (local64_add_negative(nr, &hwc->period_left)) |
7b4b6658 | 8348 | return; |
df1a132b | 8349 | |
a8b0ca17 | 8350 | perf_swevent_overflow(event, 0, data, regs); |
d6d020e9 PZ |
8351 | } |
8352 | ||
f5ffe02e FW |
8353 | static int perf_exclude_event(struct perf_event *event, |
8354 | struct pt_regs *regs) | |
8355 | { | |
a4eaf7f1 | 8356 | if (event->hw.state & PERF_HES_STOPPED) |
91b2f482 | 8357 | return 1; |
a4eaf7f1 | 8358 | |
f5ffe02e FW |
8359 | if (regs) { |
8360 | if (event->attr.exclude_user && user_mode(regs)) | |
8361 | return 1; | |
8362 | ||
8363 | if (event->attr.exclude_kernel && !user_mode(regs)) | |
8364 | return 1; | |
8365 | } | |
8366 | ||
8367 | return 0; | |
8368 | } | |
8369 | ||
cdd6c482 | 8370 | static int perf_swevent_match(struct perf_event *event, |
1c432d89 | 8371 | enum perf_type_id type, |
6fb2915d LZ |
8372 | u32 event_id, |
8373 | struct perf_sample_data *data, | |
8374 | struct pt_regs *regs) | |
15dbf27c | 8375 | { |
cdd6c482 | 8376 | if (event->attr.type != type) |
a21ca2ca | 8377 | return 0; |
f5ffe02e | 8378 | |
cdd6c482 | 8379 | if (event->attr.config != event_id) |
15dbf27c PZ |
8380 | return 0; |
8381 | ||
f5ffe02e FW |
8382 | if (perf_exclude_event(event, regs)) |
8383 | return 0; | |
15dbf27c PZ |
8384 | |
8385 | return 1; | |
8386 | } | |
8387 | ||
76e1d904 FW |
8388 | static inline u64 swevent_hash(u64 type, u32 event_id) |
8389 | { | |
8390 | u64 val = event_id | (type << 32); | |
8391 | ||
8392 | return hash_64(val, SWEVENT_HLIST_BITS); | |
8393 | } | |
8394 | ||
49f135ed FW |
8395 | static inline struct hlist_head * |
8396 | __find_swevent_head(struct swevent_hlist *hlist, u64 type, u32 event_id) | |
76e1d904 | 8397 | { |
49f135ed FW |
8398 | u64 hash = swevent_hash(type, event_id); |
8399 | ||
8400 | return &hlist->heads[hash]; | |
8401 | } | |
76e1d904 | 8402 | |
49f135ed FW |
8403 | /* For the read side: events when they trigger */ |
8404 | static inline struct hlist_head * | |
b28ab83c | 8405 | find_swevent_head_rcu(struct swevent_htable *swhash, u64 type, u32 event_id) |
49f135ed FW |
8406 | { |
8407 | struct swevent_hlist *hlist; | |
76e1d904 | 8408 | |
b28ab83c | 8409 | hlist = rcu_dereference(swhash->swevent_hlist); |
76e1d904 FW |
8410 | if (!hlist) |
8411 | return NULL; | |
8412 | ||
49f135ed FW |
8413 | return __find_swevent_head(hlist, type, event_id); |
8414 | } | |
8415 | ||
8416 | /* For the event head insertion and removal in the hlist */ | |
8417 | static inline struct hlist_head * | |
b28ab83c | 8418 | find_swevent_head(struct swevent_htable *swhash, struct perf_event *event) |
49f135ed FW |
8419 | { |
8420 | struct swevent_hlist *hlist; | |
8421 | u32 event_id = event->attr.config; | |
8422 | u64 type = event->attr.type; | |
8423 | ||
8424 | /* | |
8425 | * Event scheduling is always serialized against hlist allocation | |
8426 | * and release. Which makes the protected version suitable here. | |
8427 | * The context lock guarantees that. | |
8428 | */ | |
b28ab83c | 8429 | hlist = rcu_dereference_protected(swhash->swevent_hlist, |
49f135ed FW |
8430 | lockdep_is_held(&event->ctx->lock)); |
8431 | if (!hlist) | |
8432 | return NULL; | |
8433 | ||
8434 | return __find_swevent_head(hlist, type, event_id); | |
76e1d904 FW |
8435 | } |
8436 | ||
8437 | static void do_perf_sw_event(enum perf_type_id type, u32 event_id, | |
a8b0ca17 | 8438 | u64 nr, |
76e1d904 FW |
8439 | struct perf_sample_data *data, |
8440 | struct pt_regs *regs) | |
15dbf27c | 8441 | { |
4a32fea9 | 8442 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 8443 | struct perf_event *event; |
76e1d904 | 8444 | struct hlist_head *head; |
15dbf27c | 8445 | |
76e1d904 | 8446 | rcu_read_lock(); |
b28ab83c | 8447 | head = find_swevent_head_rcu(swhash, type, event_id); |
76e1d904 FW |
8448 | if (!head) |
8449 | goto end; | |
8450 | ||
b67bfe0d | 8451 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
6fb2915d | 8452 | if (perf_swevent_match(event, type, event_id, data, regs)) |
a8b0ca17 | 8453 | perf_swevent_event(event, nr, data, regs); |
15dbf27c | 8454 | } |
76e1d904 FW |
8455 | end: |
8456 | rcu_read_unlock(); | |
15dbf27c PZ |
8457 | } |
8458 | ||
86038c5e PZI |
8459 | DEFINE_PER_CPU(struct pt_regs, __perf_regs[4]); |
8460 | ||
4ed7c92d | 8461 | int perf_swevent_get_recursion_context(void) |
96f6d444 | 8462 | { |
4a32fea9 | 8463 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
96f6d444 | 8464 | |
b28ab83c | 8465 | return get_recursion_context(swhash->recursion); |
96f6d444 | 8466 | } |
645e8cc0 | 8467 | EXPORT_SYMBOL_GPL(perf_swevent_get_recursion_context); |
96f6d444 | 8468 | |
98b5c2c6 | 8469 | void perf_swevent_put_recursion_context(int rctx) |
15dbf27c | 8470 | { |
4a32fea9 | 8471 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
927c7a9e | 8472 | |
b28ab83c | 8473 | put_recursion_context(swhash->recursion, rctx); |
ce71b9df | 8474 | } |
15dbf27c | 8475 | |
86038c5e | 8476 | void ___perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) |
b8e83514 | 8477 | { |
a4234bfc | 8478 | struct perf_sample_data data; |
4ed7c92d | 8479 | |
86038c5e | 8480 | if (WARN_ON_ONCE(!regs)) |
4ed7c92d | 8481 | return; |
a4234bfc | 8482 | |
fd0d000b | 8483 | perf_sample_data_init(&data, addr, 0); |
a8b0ca17 | 8484 | do_perf_sw_event(PERF_TYPE_SOFTWARE, event_id, nr, &data, regs); |
86038c5e PZI |
8485 | } |
8486 | ||
8487 | void __perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) | |
8488 | { | |
8489 | int rctx; | |
8490 | ||
8491 | preempt_disable_notrace(); | |
8492 | rctx = perf_swevent_get_recursion_context(); | |
8493 | if (unlikely(rctx < 0)) | |
8494 | goto fail; | |
8495 | ||
8496 | ___perf_sw_event(event_id, nr, regs, addr); | |
4ed7c92d PZ |
8497 | |
8498 | perf_swevent_put_recursion_context(rctx); | |
86038c5e | 8499 | fail: |
1c024eca | 8500 | preempt_enable_notrace(); |
b8e83514 PZ |
8501 | } |
8502 | ||
cdd6c482 | 8503 | static void perf_swevent_read(struct perf_event *event) |
15dbf27c | 8504 | { |
15dbf27c PZ |
8505 | } |
8506 | ||
a4eaf7f1 | 8507 | static int perf_swevent_add(struct perf_event *event, int flags) |
15dbf27c | 8508 | { |
4a32fea9 | 8509 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 8510 | struct hw_perf_event *hwc = &event->hw; |
76e1d904 FW |
8511 | struct hlist_head *head; |
8512 | ||
6c7e550f | 8513 | if (is_sampling_event(event)) { |
7b4b6658 | 8514 | hwc->last_period = hwc->sample_period; |
cdd6c482 | 8515 | perf_swevent_set_period(event); |
7b4b6658 | 8516 | } |
76e1d904 | 8517 | |
a4eaf7f1 PZ |
8518 | hwc->state = !(flags & PERF_EF_START); |
8519 | ||
b28ab83c | 8520 | head = find_swevent_head(swhash, event); |
12ca6ad2 | 8521 | if (WARN_ON_ONCE(!head)) |
76e1d904 FW |
8522 | return -EINVAL; |
8523 | ||
8524 | hlist_add_head_rcu(&event->hlist_entry, head); | |
6a694a60 | 8525 | perf_event_update_userpage(event); |
76e1d904 | 8526 | |
15dbf27c PZ |
8527 | return 0; |
8528 | } | |
8529 | ||
a4eaf7f1 | 8530 | static void perf_swevent_del(struct perf_event *event, int flags) |
15dbf27c | 8531 | { |
76e1d904 | 8532 | hlist_del_rcu(&event->hlist_entry); |
15dbf27c PZ |
8533 | } |
8534 | ||
a4eaf7f1 | 8535 | static void perf_swevent_start(struct perf_event *event, int flags) |
5c92d124 | 8536 | { |
a4eaf7f1 | 8537 | event->hw.state = 0; |
d6d020e9 | 8538 | } |
aa9c4c0f | 8539 | |
a4eaf7f1 | 8540 | static void perf_swevent_stop(struct perf_event *event, int flags) |
d6d020e9 | 8541 | { |
a4eaf7f1 | 8542 | event->hw.state = PERF_HES_STOPPED; |
bae43c99 IM |
8543 | } |
8544 | ||
49f135ed FW |
8545 | /* Deref the hlist from the update side */ |
8546 | static inline struct swevent_hlist * | |
b28ab83c | 8547 | swevent_hlist_deref(struct swevent_htable *swhash) |
49f135ed | 8548 | { |
b28ab83c PZ |
8549 | return rcu_dereference_protected(swhash->swevent_hlist, |
8550 | lockdep_is_held(&swhash->hlist_mutex)); | |
49f135ed FW |
8551 | } |
8552 | ||
b28ab83c | 8553 | static void swevent_hlist_release(struct swevent_htable *swhash) |
76e1d904 | 8554 | { |
b28ab83c | 8555 | struct swevent_hlist *hlist = swevent_hlist_deref(swhash); |
76e1d904 | 8556 | |
49f135ed | 8557 | if (!hlist) |
76e1d904 FW |
8558 | return; |
8559 | ||
70691d4a | 8560 | RCU_INIT_POINTER(swhash->swevent_hlist, NULL); |
fa4bbc4c | 8561 | kfree_rcu(hlist, rcu_head); |
76e1d904 FW |
8562 | } |
8563 | ||
3b364d7b | 8564 | static void swevent_hlist_put_cpu(int cpu) |
76e1d904 | 8565 | { |
b28ab83c | 8566 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 | 8567 | |
b28ab83c | 8568 | mutex_lock(&swhash->hlist_mutex); |
76e1d904 | 8569 | |
b28ab83c PZ |
8570 | if (!--swhash->hlist_refcount) |
8571 | swevent_hlist_release(swhash); | |
76e1d904 | 8572 | |
b28ab83c | 8573 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
8574 | } |
8575 | ||
3b364d7b | 8576 | static void swevent_hlist_put(void) |
76e1d904 FW |
8577 | { |
8578 | int cpu; | |
8579 | ||
76e1d904 | 8580 | for_each_possible_cpu(cpu) |
3b364d7b | 8581 | swevent_hlist_put_cpu(cpu); |
76e1d904 FW |
8582 | } |
8583 | ||
3b364d7b | 8584 | static int swevent_hlist_get_cpu(int cpu) |
76e1d904 | 8585 | { |
b28ab83c | 8586 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 FW |
8587 | int err = 0; |
8588 | ||
b28ab83c | 8589 | mutex_lock(&swhash->hlist_mutex); |
a63fbed7 TG |
8590 | if (!swevent_hlist_deref(swhash) && |
8591 | cpumask_test_cpu(cpu, perf_online_mask)) { | |
76e1d904 FW |
8592 | struct swevent_hlist *hlist; |
8593 | ||
8594 | hlist = kzalloc(sizeof(*hlist), GFP_KERNEL); | |
8595 | if (!hlist) { | |
8596 | err = -ENOMEM; | |
8597 | goto exit; | |
8598 | } | |
b28ab83c | 8599 | rcu_assign_pointer(swhash->swevent_hlist, hlist); |
76e1d904 | 8600 | } |
b28ab83c | 8601 | swhash->hlist_refcount++; |
9ed6060d | 8602 | exit: |
b28ab83c | 8603 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
8604 | |
8605 | return err; | |
8606 | } | |
8607 | ||
3b364d7b | 8608 | static int swevent_hlist_get(void) |
76e1d904 | 8609 | { |
3b364d7b | 8610 | int err, cpu, failed_cpu; |
76e1d904 | 8611 | |
a63fbed7 | 8612 | mutex_lock(&pmus_lock); |
76e1d904 | 8613 | for_each_possible_cpu(cpu) { |
3b364d7b | 8614 | err = swevent_hlist_get_cpu(cpu); |
76e1d904 FW |
8615 | if (err) { |
8616 | failed_cpu = cpu; | |
8617 | goto fail; | |
8618 | } | |
8619 | } | |
a63fbed7 | 8620 | mutex_unlock(&pmus_lock); |
76e1d904 | 8621 | return 0; |
9ed6060d | 8622 | fail: |
76e1d904 FW |
8623 | for_each_possible_cpu(cpu) { |
8624 | if (cpu == failed_cpu) | |
8625 | break; | |
3b364d7b | 8626 | swevent_hlist_put_cpu(cpu); |
76e1d904 | 8627 | } |
a63fbed7 | 8628 | mutex_unlock(&pmus_lock); |
76e1d904 FW |
8629 | return err; |
8630 | } | |
8631 | ||
c5905afb | 8632 | struct static_key perf_swevent_enabled[PERF_COUNT_SW_MAX]; |
95476b64 | 8633 | |
b0a873eb PZ |
8634 | static void sw_perf_event_destroy(struct perf_event *event) |
8635 | { | |
8636 | u64 event_id = event->attr.config; | |
95476b64 | 8637 | |
b0a873eb PZ |
8638 | WARN_ON(event->parent); |
8639 | ||
c5905afb | 8640 | static_key_slow_dec(&perf_swevent_enabled[event_id]); |
3b364d7b | 8641 | swevent_hlist_put(); |
b0a873eb PZ |
8642 | } |
8643 | ||
8644 | static int perf_swevent_init(struct perf_event *event) | |
8645 | { | |
8176cced | 8646 | u64 event_id = event->attr.config; |
b0a873eb PZ |
8647 | |
8648 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
8649 | return -ENOENT; | |
8650 | ||
2481c5fa SE |
8651 | /* |
8652 | * no branch sampling for software events | |
8653 | */ | |
8654 | if (has_branch_stack(event)) | |
8655 | return -EOPNOTSUPP; | |
8656 | ||
b0a873eb PZ |
8657 | switch (event_id) { |
8658 | case PERF_COUNT_SW_CPU_CLOCK: | |
8659 | case PERF_COUNT_SW_TASK_CLOCK: | |
8660 | return -ENOENT; | |
8661 | ||
8662 | default: | |
8663 | break; | |
8664 | } | |
8665 | ||
ce677831 | 8666 | if (event_id >= PERF_COUNT_SW_MAX) |
b0a873eb PZ |
8667 | return -ENOENT; |
8668 | ||
8669 | if (!event->parent) { | |
8670 | int err; | |
8671 | ||
3b364d7b | 8672 | err = swevent_hlist_get(); |
b0a873eb PZ |
8673 | if (err) |
8674 | return err; | |
8675 | ||
c5905afb | 8676 | static_key_slow_inc(&perf_swevent_enabled[event_id]); |
b0a873eb PZ |
8677 | event->destroy = sw_perf_event_destroy; |
8678 | } | |
8679 | ||
8680 | return 0; | |
8681 | } | |
8682 | ||
8683 | static struct pmu perf_swevent = { | |
89a1e187 | 8684 | .task_ctx_nr = perf_sw_context, |
95476b64 | 8685 | |
34f43927 PZ |
8686 | .capabilities = PERF_PMU_CAP_NO_NMI, |
8687 | ||
b0a873eb | 8688 | .event_init = perf_swevent_init, |
a4eaf7f1 PZ |
8689 | .add = perf_swevent_add, |
8690 | .del = perf_swevent_del, | |
8691 | .start = perf_swevent_start, | |
8692 | .stop = perf_swevent_stop, | |
1c024eca | 8693 | .read = perf_swevent_read, |
1c024eca PZ |
8694 | }; |
8695 | ||
b0a873eb PZ |
8696 | #ifdef CONFIG_EVENT_TRACING |
8697 | ||
1c024eca PZ |
8698 | static int perf_tp_filter_match(struct perf_event *event, |
8699 | struct perf_sample_data *data) | |
8700 | { | |
7e3f977e | 8701 | void *record = data->raw->frag.data; |
1c024eca | 8702 | |
b71b437e PZ |
8703 | /* only top level events have filters set */ |
8704 | if (event->parent) | |
8705 | event = event->parent; | |
8706 | ||
1c024eca PZ |
8707 | if (likely(!event->filter) || filter_match_preds(event->filter, record)) |
8708 | return 1; | |
8709 | return 0; | |
8710 | } | |
8711 | ||
8712 | static int perf_tp_event_match(struct perf_event *event, | |
8713 | struct perf_sample_data *data, | |
8714 | struct pt_regs *regs) | |
8715 | { | |
a0f7d0f7 FW |
8716 | if (event->hw.state & PERF_HES_STOPPED) |
8717 | return 0; | |
580d607c | 8718 | /* |
9fd2e48b | 8719 | * If exclude_kernel, only trace user-space tracepoints (uprobes) |
580d607c | 8720 | */ |
9fd2e48b | 8721 | if (event->attr.exclude_kernel && !user_mode(regs)) |
1c024eca PZ |
8722 | return 0; |
8723 | ||
8724 | if (!perf_tp_filter_match(event, data)) | |
8725 | return 0; | |
8726 | ||
8727 | return 1; | |
8728 | } | |
8729 | ||
85b67bcb AS |
8730 | void perf_trace_run_bpf_submit(void *raw_data, int size, int rctx, |
8731 | struct trace_event_call *call, u64 count, | |
8732 | struct pt_regs *regs, struct hlist_head *head, | |
8733 | struct task_struct *task) | |
8734 | { | |
e87c6bc3 | 8735 | if (bpf_prog_array_valid(call)) { |
85b67bcb | 8736 | *(struct pt_regs **)raw_data = regs; |
e87c6bc3 | 8737 | if (!trace_call_bpf(call, raw_data) || hlist_empty(head)) { |
85b67bcb AS |
8738 | perf_swevent_put_recursion_context(rctx); |
8739 | return; | |
8740 | } | |
8741 | } | |
8742 | perf_tp_event(call->event.type, count, raw_data, size, regs, head, | |
8fd0fbbe | 8743 | rctx, task); |
85b67bcb AS |
8744 | } |
8745 | EXPORT_SYMBOL_GPL(perf_trace_run_bpf_submit); | |
8746 | ||
1e1dcd93 | 8747 | void perf_tp_event(u16 event_type, u64 count, void *record, int entry_size, |
e6dab5ff | 8748 | struct pt_regs *regs, struct hlist_head *head, int rctx, |
8fd0fbbe | 8749 | struct task_struct *task) |
95476b64 FW |
8750 | { |
8751 | struct perf_sample_data data; | |
8fd0fbbe | 8752 | struct perf_event *event; |
1c024eca | 8753 | |
95476b64 | 8754 | struct perf_raw_record raw = { |
7e3f977e DB |
8755 | .frag = { |
8756 | .size = entry_size, | |
8757 | .data = record, | |
8758 | }, | |
95476b64 FW |
8759 | }; |
8760 | ||
1e1dcd93 | 8761 | perf_sample_data_init(&data, 0, 0); |
95476b64 FW |
8762 | data.raw = &raw; |
8763 | ||
1e1dcd93 AS |
8764 | perf_trace_buf_update(record, event_type); |
8765 | ||
8fd0fbbe | 8766 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
1c024eca | 8767 | if (perf_tp_event_match(event, &data, regs)) |
a8b0ca17 | 8768 | perf_swevent_event(event, count, &data, regs); |
4f41c013 | 8769 | } |
ecc55f84 | 8770 | |
e6dab5ff AV |
8771 | /* |
8772 | * If we got specified a target task, also iterate its context and | |
8773 | * deliver this event there too. | |
8774 | */ | |
8775 | if (task && task != current) { | |
8776 | struct perf_event_context *ctx; | |
8777 | struct trace_entry *entry = record; | |
8778 | ||
8779 | rcu_read_lock(); | |
8780 | ctx = rcu_dereference(task->perf_event_ctxp[perf_sw_context]); | |
8781 | if (!ctx) | |
8782 | goto unlock; | |
8783 | ||
8784 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
cd6fb677 JO |
8785 | if (event->cpu != smp_processor_id()) |
8786 | continue; | |
e6dab5ff AV |
8787 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
8788 | continue; | |
8789 | if (event->attr.config != entry->type) | |
8790 | continue; | |
8791 | if (perf_tp_event_match(event, &data, regs)) | |
8792 | perf_swevent_event(event, count, &data, regs); | |
8793 | } | |
8794 | unlock: | |
8795 | rcu_read_unlock(); | |
8796 | } | |
8797 | ||
ecc55f84 | 8798 | perf_swevent_put_recursion_context(rctx); |
95476b64 FW |
8799 | } |
8800 | EXPORT_SYMBOL_GPL(perf_tp_event); | |
8801 | ||
cdd6c482 | 8802 | static void tp_perf_event_destroy(struct perf_event *event) |
e077df4f | 8803 | { |
1c024eca | 8804 | perf_trace_destroy(event); |
e077df4f PZ |
8805 | } |
8806 | ||
b0a873eb | 8807 | static int perf_tp_event_init(struct perf_event *event) |
e077df4f | 8808 | { |
76e1d904 FW |
8809 | int err; |
8810 | ||
b0a873eb PZ |
8811 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
8812 | return -ENOENT; | |
8813 | ||
2481c5fa SE |
8814 | /* |
8815 | * no branch sampling for tracepoint events | |
8816 | */ | |
8817 | if (has_branch_stack(event)) | |
8818 | return -EOPNOTSUPP; | |
8819 | ||
1c024eca PZ |
8820 | err = perf_trace_init(event); |
8821 | if (err) | |
b0a873eb | 8822 | return err; |
e077df4f | 8823 | |
cdd6c482 | 8824 | event->destroy = tp_perf_event_destroy; |
e077df4f | 8825 | |
b0a873eb PZ |
8826 | return 0; |
8827 | } | |
8828 | ||
8829 | static struct pmu perf_tracepoint = { | |
89a1e187 PZ |
8830 | .task_ctx_nr = perf_sw_context, |
8831 | ||
b0a873eb | 8832 | .event_init = perf_tp_event_init, |
a4eaf7f1 PZ |
8833 | .add = perf_trace_add, |
8834 | .del = perf_trace_del, | |
8835 | .start = perf_swevent_start, | |
8836 | .stop = perf_swevent_stop, | |
b0a873eb | 8837 | .read = perf_swevent_read, |
b0a873eb PZ |
8838 | }; |
8839 | ||
33ea4b24 | 8840 | #if defined(CONFIG_KPROBE_EVENTS) || defined(CONFIG_UPROBE_EVENTS) |
e12f03d7 SL |
8841 | /* |
8842 | * Flags in config, used by dynamic PMU kprobe and uprobe | |
8843 | * The flags should match following PMU_FORMAT_ATTR(). | |
8844 | * | |
8845 | * PERF_PROBE_CONFIG_IS_RETPROBE if set, create kretprobe/uretprobe | |
8846 | * if not set, create kprobe/uprobe | |
a6ca88b2 SL |
8847 | * |
8848 | * The following values specify a reference counter (or semaphore in the | |
8849 | * terminology of tools like dtrace, systemtap, etc.) Userspace Statically | |
8850 | * Defined Tracepoints (USDT). Currently, we use 40 bit for the offset. | |
8851 | * | |
8852 | * PERF_UPROBE_REF_CTR_OFFSET_BITS # of bits in config as th offset | |
8853 | * PERF_UPROBE_REF_CTR_OFFSET_SHIFT # of bits to shift left | |
e12f03d7 SL |
8854 | */ |
8855 | enum perf_probe_config { | |
8856 | PERF_PROBE_CONFIG_IS_RETPROBE = 1U << 0, /* [k,u]retprobe */ | |
a6ca88b2 SL |
8857 | PERF_UPROBE_REF_CTR_OFFSET_BITS = 32, |
8858 | PERF_UPROBE_REF_CTR_OFFSET_SHIFT = 64 - PERF_UPROBE_REF_CTR_OFFSET_BITS, | |
e12f03d7 SL |
8859 | }; |
8860 | ||
8861 | PMU_FORMAT_ATTR(retprobe, "config:0"); | |
a6ca88b2 | 8862 | #endif |
e12f03d7 | 8863 | |
a6ca88b2 SL |
8864 | #ifdef CONFIG_KPROBE_EVENTS |
8865 | static struct attribute *kprobe_attrs[] = { | |
e12f03d7 SL |
8866 | &format_attr_retprobe.attr, |
8867 | NULL, | |
8868 | }; | |
8869 | ||
a6ca88b2 | 8870 | static struct attribute_group kprobe_format_group = { |
e12f03d7 | 8871 | .name = "format", |
a6ca88b2 | 8872 | .attrs = kprobe_attrs, |
e12f03d7 SL |
8873 | }; |
8874 | ||
a6ca88b2 SL |
8875 | static const struct attribute_group *kprobe_attr_groups[] = { |
8876 | &kprobe_format_group, | |
e12f03d7 SL |
8877 | NULL, |
8878 | }; | |
8879 | ||
8880 | static int perf_kprobe_event_init(struct perf_event *event); | |
8881 | static struct pmu perf_kprobe = { | |
8882 | .task_ctx_nr = perf_sw_context, | |
8883 | .event_init = perf_kprobe_event_init, | |
8884 | .add = perf_trace_add, | |
8885 | .del = perf_trace_del, | |
8886 | .start = perf_swevent_start, | |
8887 | .stop = perf_swevent_stop, | |
8888 | .read = perf_swevent_read, | |
a6ca88b2 | 8889 | .attr_groups = kprobe_attr_groups, |
e12f03d7 SL |
8890 | }; |
8891 | ||
8892 | static int perf_kprobe_event_init(struct perf_event *event) | |
8893 | { | |
8894 | int err; | |
8895 | bool is_retprobe; | |
8896 | ||
8897 | if (event->attr.type != perf_kprobe.type) | |
8898 | return -ENOENT; | |
32e6e967 SL |
8899 | |
8900 | if (!capable(CAP_SYS_ADMIN)) | |
8901 | return -EACCES; | |
8902 | ||
e12f03d7 SL |
8903 | /* |
8904 | * no branch sampling for probe events | |
8905 | */ | |
8906 | if (has_branch_stack(event)) | |
8907 | return -EOPNOTSUPP; | |
8908 | ||
8909 | is_retprobe = event->attr.config & PERF_PROBE_CONFIG_IS_RETPROBE; | |
8910 | err = perf_kprobe_init(event, is_retprobe); | |
8911 | if (err) | |
8912 | return err; | |
8913 | ||
8914 | event->destroy = perf_kprobe_destroy; | |
8915 | ||
8916 | return 0; | |
8917 | } | |
8918 | #endif /* CONFIG_KPROBE_EVENTS */ | |
8919 | ||
33ea4b24 | 8920 | #ifdef CONFIG_UPROBE_EVENTS |
a6ca88b2 SL |
8921 | PMU_FORMAT_ATTR(ref_ctr_offset, "config:32-63"); |
8922 | ||
8923 | static struct attribute *uprobe_attrs[] = { | |
8924 | &format_attr_retprobe.attr, | |
8925 | &format_attr_ref_ctr_offset.attr, | |
8926 | NULL, | |
8927 | }; | |
8928 | ||
8929 | static struct attribute_group uprobe_format_group = { | |
8930 | .name = "format", | |
8931 | .attrs = uprobe_attrs, | |
8932 | }; | |
8933 | ||
8934 | static const struct attribute_group *uprobe_attr_groups[] = { | |
8935 | &uprobe_format_group, | |
8936 | NULL, | |
8937 | }; | |
8938 | ||
33ea4b24 SL |
8939 | static int perf_uprobe_event_init(struct perf_event *event); |
8940 | static struct pmu perf_uprobe = { | |
8941 | .task_ctx_nr = perf_sw_context, | |
8942 | .event_init = perf_uprobe_event_init, | |
8943 | .add = perf_trace_add, | |
8944 | .del = perf_trace_del, | |
8945 | .start = perf_swevent_start, | |
8946 | .stop = perf_swevent_stop, | |
8947 | .read = perf_swevent_read, | |
a6ca88b2 | 8948 | .attr_groups = uprobe_attr_groups, |
33ea4b24 SL |
8949 | }; |
8950 | ||
8951 | static int perf_uprobe_event_init(struct perf_event *event) | |
8952 | { | |
8953 | int err; | |
a6ca88b2 | 8954 | unsigned long ref_ctr_offset; |
33ea4b24 SL |
8955 | bool is_retprobe; |
8956 | ||
8957 | if (event->attr.type != perf_uprobe.type) | |
8958 | return -ENOENT; | |
32e6e967 SL |
8959 | |
8960 | if (!capable(CAP_SYS_ADMIN)) | |
8961 | return -EACCES; | |
8962 | ||
33ea4b24 SL |
8963 | /* |
8964 | * no branch sampling for probe events | |
8965 | */ | |
8966 | if (has_branch_stack(event)) | |
8967 | return -EOPNOTSUPP; | |
8968 | ||
8969 | is_retprobe = event->attr.config & PERF_PROBE_CONFIG_IS_RETPROBE; | |
a6ca88b2 SL |
8970 | ref_ctr_offset = event->attr.config >> PERF_UPROBE_REF_CTR_OFFSET_SHIFT; |
8971 | err = perf_uprobe_init(event, ref_ctr_offset, is_retprobe); | |
33ea4b24 SL |
8972 | if (err) |
8973 | return err; | |
8974 | ||
8975 | event->destroy = perf_uprobe_destroy; | |
8976 | ||
8977 | return 0; | |
8978 | } | |
8979 | #endif /* CONFIG_UPROBE_EVENTS */ | |
8980 | ||
b0a873eb PZ |
8981 | static inline void perf_tp_register(void) |
8982 | { | |
2e80a82a | 8983 | perf_pmu_register(&perf_tracepoint, "tracepoint", PERF_TYPE_TRACEPOINT); |
e12f03d7 SL |
8984 | #ifdef CONFIG_KPROBE_EVENTS |
8985 | perf_pmu_register(&perf_kprobe, "kprobe", -1); | |
8986 | #endif | |
33ea4b24 SL |
8987 | #ifdef CONFIG_UPROBE_EVENTS |
8988 | perf_pmu_register(&perf_uprobe, "uprobe", -1); | |
8989 | #endif | |
e077df4f | 8990 | } |
6fb2915d | 8991 | |
6fb2915d LZ |
8992 | static void perf_event_free_filter(struct perf_event *event) |
8993 | { | |
8994 | ftrace_profile_free_filter(event); | |
8995 | } | |
8996 | ||
aa6a5f3c AS |
8997 | #ifdef CONFIG_BPF_SYSCALL |
8998 | static void bpf_overflow_handler(struct perf_event *event, | |
8999 | struct perf_sample_data *data, | |
9000 | struct pt_regs *regs) | |
9001 | { | |
9002 | struct bpf_perf_event_data_kern ctx = { | |
9003 | .data = data, | |
7d9285e8 | 9004 | .event = event, |
aa6a5f3c AS |
9005 | }; |
9006 | int ret = 0; | |
9007 | ||
c895f6f7 | 9008 | ctx.regs = perf_arch_bpf_user_pt_regs(regs); |
aa6a5f3c AS |
9009 | preempt_disable(); |
9010 | if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) | |
9011 | goto out; | |
9012 | rcu_read_lock(); | |
88575199 | 9013 | ret = BPF_PROG_RUN(event->prog, &ctx); |
aa6a5f3c AS |
9014 | rcu_read_unlock(); |
9015 | out: | |
9016 | __this_cpu_dec(bpf_prog_active); | |
9017 | preempt_enable(); | |
9018 | if (!ret) | |
9019 | return; | |
9020 | ||
9021 | event->orig_overflow_handler(event, data, regs); | |
9022 | } | |
9023 | ||
9024 | static int perf_event_set_bpf_handler(struct perf_event *event, u32 prog_fd) | |
9025 | { | |
9026 | struct bpf_prog *prog; | |
9027 | ||
9028 | if (event->overflow_handler_context) | |
9029 | /* hw breakpoint or kernel counter */ | |
9030 | return -EINVAL; | |
9031 | ||
9032 | if (event->prog) | |
9033 | return -EEXIST; | |
9034 | ||
9035 | prog = bpf_prog_get_type(prog_fd, BPF_PROG_TYPE_PERF_EVENT); | |
9036 | if (IS_ERR(prog)) | |
9037 | return PTR_ERR(prog); | |
9038 | ||
9039 | event->prog = prog; | |
9040 | event->orig_overflow_handler = READ_ONCE(event->overflow_handler); | |
9041 | WRITE_ONCE(event->overflow_handler, bpf_overflow_handler); | |
9042 | return 0; | |
9043 | } | |
9044 | ||
9045 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
9046 | { | |
9047 | struct bpf_prog *prog = event->prog; | |
9048 | ||
9049 | if (!prog) | |
9050 | return; | |
9051 | ||
9052 | WRITE_ONCE(event->overflow_handler, event->orig_overflow_handler); | |
9053 | event->prog = NULL; | |
9054 | bpf_prog_put(prog); | |
9055 | } | |
9056 | #else | |
9057 | static int perf_event_set_bpf_handler(struct perf_event *event, u32 prog_fd) | |
9058 | { | |
9059 | return -EOPNOTSUPP; | |
9060 | } | |
9061 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
9062 | { | |
9063 | } | |
9064 | #endif | |
9065 | ||
e12f03d7 SL |
9066 | /* |
9067 | * returns true if the event is a tracepoint, or a kprobe/upprobe created | |
9068 | * with perf_event_open() | |
9069 | */ | |
9070 | static inline bool perf_event_is_tracing(struct perf_event *event) | |
9071 | { | |
9072 | if (event->pmu == &perf_tracepoint) | |
9073 | return true; | |
9074 | #ifdef CONFIG_KPROBE_EVENTS | |
9075 | if (event->pmu == &perf_kprobe) | |
9076 | return true; | |
33ea4b24 SL |
9077 | #endif |
9078 | #ifdef CONFIG_UPROBE_EVENTS | |
9079 | if (event->pmu == &perf_uprobe) | |
9080 | return true; | |
e12f03d7 SL |
9081 | #endif |
9082 | return false; | |
9083 | } | |
9084 | ||
2541517c AS |
9085 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
9086 | { | |
cf5f5cea | 9087 | bool is_kprobe, is_tracepoint, is_syscall_tp; |
2541517c | 9088 | struct bpf_prog *prog; |
e87c6bc3 | 9089 | int ret; |
2541517c | 9090 | |
e12f03d7 | 9091 | if (!perf_event_is_tracing(event)) |
f91840a3 | 9092 | return perf_event_set_bpf_handler(event, prog_fd); |
2541517c | 9093 | |
98b5c2c6 AS |
9094 | is_kprobe = event->tp_event->flags & TRACE_EVENT_FL_UKPROBE; |
9095 | is_tracepoint = event->tp_event->flags & TRACE_EVENT_FL_TRACEPOINT; | |
cf5f5cea YS |
9096 | is_syscall_tp = is_syscall_trace_event(event->tp_event); |
9097 | if (!is_kprobe && !is_tracepoint && !is_syscall_tp) | |
98b5c2c6 | 9098 | /* bpf programs can only be attached to u/kprobe or tracepoint */ |
2541517c AS |
9099 | return -EINVAL; |
9100 | ||
9101 | prog = bpf_prog_get(prog_fd); | |
9102 | if (IS_ERR(prog)) | |
9103 | return PTR_ERR(prog); | |
9104 | ||
98b5c2c6 | 9105 | if ((is_kprobe && prog->type != BPF_PROG_TYPE_KPROBE) || |
cf5f5cea YS |
9106 | (is_tracepoint && prog->type != BPF_PROG_TYPE_TRACEPOINT) || |
9107 | (is_syscall_tp && prog->type != BPF_PROG_TYPE_TRACEPOINT)) { | |
2541517c AS |
9108 | /* valid fd, but invalid bpf program type */ |
9109 | bpf_prog_put(prog); | |
9110 | return -EINVAL; | |
9111 | } | |
9112 | ||
9802d865 JB |
9113 | /* Kprobe override only works for kprobes, not uprobes. */ |
9114 | if (prog->kprobe_override && | |
9115 | !(event->tp_event->flags & TRACE_EVENT_FL_KPROBE)) { | |
9116 | bpf_prog_put(prog); | |
9117 | return -EINVAL; | |
9118 | } | |
9119 | ||
cf5f5cea | 9120 | if (is_tracepoint || is_syscall_tp) { |
32bbe007 AS |
9121 | int off = trace_event_get_offsets(event->tp_event); |
9122 | ||
9123 | if (prog->aux->max_ctx_offset > off) { | |
9124 | bpf_prog_put(prog); | |
9125 | return -EACCES; | |
9126 | } | |
9127 | } | |
2541517c | 9128 | |
e87c6bc3 YS |
9129 | ret = perf_event_attach_bpf_prog(event, prog); |
9130 | if (ret) | |
9131 | bpf_prog_put(prog); | |
9132 | return ret; | |
2541517c AS |
9133 | } |
9134 | ||
9135 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
9136 | { | |
e12f03d7 | 9137 | if (!perf_event_is_tracing(event)) { |
0b4c6841 | 9138 | perf_event_free_bpf_handler(event); |
2541517c | 9139 | return; |
2541517c | 9140 | } |
e87c6bc3 | 9141 | perf_event_detach_bpf_prog(event); |
2541517c AS |
9142 | } |
9143 | ||
e077df4f | 9144 | #else |
6fb2915d | 9145 | |
b0a873eb | 9146 | static inline void perf_tp_register(void) |
e077df4f | 9147 | { |
e077df4f | 9148 | } |
6fb2915d | 9149 | |
6fb2915d LZ |
9150 | static void perf_event_free_filter(struct perf_event *event) |
9151 | { | |
9152 | } | |
9153 | ||
2541517c AS |
9154 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
9155 | { | |
9156 | return -ENOENT; | |
9157 | } | |
9158 | ||
9159 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
9160 | { | |
9161 | } | |
07b139c8 | 9162 | #endif /* CONFIG_EVENT_TRACING */ |
e077df4f | 9163 | |
24f1e32c | 9164 | #ifdef CONFIG_HAVE_HW_BREAKPOINT |
f5ffe02e | 9165 | void perf_bp_event(struct perf_event *bp, void *data) |
24f1e32c | 9166 | { |
f5ffe02e FW |
9167 | struct perf_sample_data sample; |
9168 | struct pt_regs *regs = data; | |
9169 | ||
fd0d000b | 9170 | perf_sample_data_init(&sample, bp->attr.bp_addr, 0); |
f5ffe02e | 9171 | |
a4eaf7f1 | 9172 | if (!bp->hw.state && !perf_exclude_event(bp, regs)) |
a8b0ca17 | 9173 | perf_swevent_event(bp, 1, &sample, regs); |
24f1e32c FW |
9174 | } |
9175 | #endif | |
9176 | ||
375637bc AS |
9177 | /* |
9178 | * Allocate a new address filter | |
9179 | */ | |
9180 | static struct perf_addr_filter * | |
9181 | perf_addr_filter_new(struct perf_event *event, struct list_head *filters) | |
9182 | { | |
9183 | int node = cpu_to_node(event->cpu == -1 ? 0 : event->cpu); | |
9184 | struct perf_addr_filter *filter; | |
9185 | ||
9186 | filter = kzalloc_node(sizeof(*filter), GFP_KERNEL, node); | |
9187 | if (!filter) | |
9188 | return NULL; | |
9189 | ||
9190 | INIT_LIST_HEAD(&filter->entry); | |
9191 | list_add_tail(&filter->entry, filters); | |
9192 | ||
9193 | return filter; | |
9194 | } | |
9195 | ||
9196 | static void free_filters_list(struct list_head *filters) | |
9197 | { | |
9198 | struct perf_addr_filter *filter, *iter; | |
9199 | ||
9200 | list_for_each_entry_safe(filter, iter, filters, entry) { | |
9511bce9 | 9201 | path_put(&filter->path); |
375637bc AS |
9202 | list_del(&filter->entry); |
9203 | kfree(filter); | |
9204 | } | |
9205 | } | |
9206 | ||
9207 | /* | |
9208 | * Free existing address filters and optionally install new ones | |
9209 | */ | |
9210 | static void perf_addr_filters_splice(struct perf_event *event, | |
9211 | struct list_head *head) | |
9212 | { | |
9213 | unsigned long flags; | |
9214 | LIST_HEAD(list); | |
9215 | ||
9216 | if (!has_addr_filter(event)) | |
9217 | return; | |
9218 | ||
9219 | /* don't bother with children, they don't have their own filters */ | |
9220 | if (event->parent) | |
9221 | return; | |
9222 | ||
9223 | raw_spin_lock_irqsave(&event->addr_filters.lock, flags); | |
9224 | ||
9225 | list_splice_init(&event->addr_filters.list, &list); | |
9226 | if (head) | |
9227 | list_splice(head, &event->addr_filters.list); | |
9228 | ||
9229 | raw_spin_unlock_irqrestore(&event->addr_filters.lock, flags); | |
9230 | ||
9231 | free_filters_list(&list); | |
9232 | } | |
9233 | ||
9234 | /* | |
9235 | * Scan through mm's vmas and see if one of them matches the | |
9236 | * @filter; if so, adjust filter's address range. | |
9237 | * Called with mm::mmap_sem down for reading. | |
9238 | */ | |
c60f83b8 AS |
9239 | static void perf_addr_filter_apply(struct perf_addr_filter *filter, |
9240 | struct mm_struct *mm, | |
9241 | struct perf_addr_filter_range *fr) | |
375637bc AS |
9242 | { |
9243 | struct vm_area_struct *vma; | |
9244 | ||
9245 | for (vma = mm->mmap; vma; vma = vma->vm_next) { | |
c60f83b8 | 9246 | if (!vma->vm_file) |
375637bc AS |
9247 | continue; |
9248 | ||
c60f83b8 AS |
9249 | if (perf_addr_filter_vma_adjust(filter, vma, fr)) |
9250 | return; | |
375637bc | 9251 | } |
375637bc AS |
9252 | } |
9253 | ||
9254 | /* | |
9255 | * Update event's address range filters based on the | |
9256 | * task's existing mappings, if any. | |
9257 | */ | |
9258 | static void perf_event_addr_filters_apply(struct perf_event *event) | |
9259 | { | |
9260 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
9261 | struct task_struct *task = READ_ONCE(event->ctx->task); | |
9262 | struct perf_addr_filter *filter; | |
9263 | struct mm_struct *mm = NULL; | |
9264 | unsigned int count = 0; | |
9265 | unsigned long flags; | |
9266 | ||
9267 | /* | |
9268 | * We may observe TASK_TOMBSTONE, which means that the event tear-down | |
9269 | * will stop on the parent's child_mutex that our caller is also holding | |
9270 | */ | |
9271 | if (task == TASK_TOMBSTONE) | |
9272 | return; | |
9273 | ||
52a44f83 AS |
9274 | if (ifh->nr_file_filters) { |
9275 | mm = get_task_mm(event->ctx->task); | |
9276 | if (!mm) | |
9277 | goto restart; | |
375637bc | 9278 | |
52a44f83 AS |
9279 | down_read(&mm->mmap_sem); |
9280 | } | |
375637bc AS |
9281 | |
9282 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
9283 | list_for_each_entry(filter, &ifh->list, entry) { | |
52a44f83 AS |
9284 | if (filter->path.dentry) { |
9285 | /* | |
9286 | * Adjust base offset if the filter is associated to a | |
9287 | * binary that needs to be mapped: | |
9288 | */ | |
9289 | event->addr_filter_ranges[count].start = 0; | |
9290 | event->addr_filter_ranges[count].size = 0; | |
375637bc | 9291 | |
c60f83b8 | 9292 | perf_addr_filter_apply(filter, mm, &event->addr_filter_ranges[count]); |
52a44f83 AS |
9293 | } else { |
9294 | event->addr_filter_ranges[count].start = filter->offset; | |
9295 | event->addr_filter_ranges[count].size = filter->size; | |
9296 | } | |
375637bc AS |
9297 | |
9298 | count++; | |
9299 | } | |
9300 | ||
9301 | event->addr_filters_gen++; | |
9302 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
9303 | ||
52a44f83 AS |
9304 | if (ifh->nr_file_filters) { |
9305 | up_read(&mm->mmap_sem); | |
375637bc | 9306 | |
52a44f83 AS |
9307 | mmput(mm); |
9308 | } | |
375637bc AS |
9309 | |
9310 | restart: | |
767ae086 | 9311 | perf_event_stop(event, 1); |
375637bc AS |
9312 | } |
9313 | ||
9314 | /* | |
9315 | * Address range filtering: limiting the data to certain | |
9316 | * instruction address ranges. Filters are ioctl()ed to us from | |
9317 | * userspace as ascii strings. | |
9318 | * | |
9319 | * Filter string format: | |
9320 | * | |
9321 | * ACTION RANGE_SPEC | |
9322 | * where ACTION is one of the | |
9323 | * * "filter": limit the trace to this region | |
9324 | * * "start": start tracing from this address | |
9325 | * * "stop": stop tracing at this address/region; | |
9326 | * RANGE_SPEC is | |
9327 | * * for kernel addresses: <start address>[/<size>] | |
9328 | * * for object files: <start address>[/<size>]@</path/to/object/file> | |
9329 | * | |
6ed70cf3 AS |
9330 | * if <size> is not specified or is zero, the range is treated as a single |
9331 | * address; not valid for ACTION=="filter". | |
375637bc AS |
9332 | */ |
9333 | enum { | |
e96271f3 | 9334 | IF_ACT_NONE = -1, |
375637bc AS |
9335 | IF_ACT_FILTER, |
9336 | IF_ACT_START, | |
9337 | IF_ACT_STOP, | |
9338 | IF_SRC_FILE, | |
9339 | IF_SRC_KERNEL, | |
9340 | IF_SRC_FILEADDR, | |
9341 | IF_SRC_KERNELADDR, | |
9342 | }; | |
9343 | ||
9344 | enum { | |
9345 | IF_STATE_ACTION = 0, | |
9346 | IF_STATE_SOURCE, | |
9347 | IF_STATE_END, | |
9348 | }; | |
9349 | ||
9350 | static const match_table_t if_tokens = { | |
9351 | { IF_ACT_FILTER, "filter" }, | |
9352 | { IF_ACT_START, "start" }, | |
9353 | { IF_ACT_STOP, "stop" }, | |
9354 | { IF_SRC_FILE, "%u/%u@%s" }, | |
9355 | { IF_SRC_KERNEL, "%u/%u" }, | |
9356 | { IF_SRC_FILEADDR, "%u@%s" }, | |
9357 | { IF_SRC_KERNELADDR, "%u" }, | |
e96271f3 | 9358 | { IF_ACT_NONE, NULL }, |
375637bc AS |
9359 | }; |
9360 | ||
9361 | /* | |
9362 | * Address filter string parser | |
9363 | */ | |
9364 | static int | |
9365 | perf_event_parse_addr_filter(struct perf_event *event, char *fstr, | |
9366 | struct list_head *filters) | |
9367 | { | |
9368 | struct perf_addr_filter *filter = NULL; | |
9369 | char *start, *orig, *filename = NULL; | |
375637bc AS |
9370 | substring_t args[MAX_OPT_ARGS]; |
9371 | int state = IF_STATE_ACTION, token; | |
9372 | unsigned int kernel = 0; | |
9373 | int ret = -EINVAL; | |
9374 | ||
9375 | orig = fstr = kstrdup(fstr, GFP_KERNEL); | |
9376 | if (!fstr) | |
9377 | return -ENOMEM; | |
9378 | ||
9379 | while ((start = strsep(&fstr, " ,\n")) != NULL) { | |
6ed70cf3 AS |
9380 | static const enum perf_addr_filter_action_t actions[] = { |
9381 | [IF_ACT_FILTER] = PERF_ADDR_FILTER_ACTION_FILTER, | |
9382 | [IF_ACT_START] = PERF_ADDR_FILTER_ACTION_START, | |
9383 | [IF_ACT_STOP] = PERF_ADDR_FILTER_ACTION_STOP, | |
9384 | }; | |
375637bc AS |
9385 | ret = -EINVAL; |
9386 | ||
9387 | if (!*start) | |
9388 | continue; | |
9389 | ||
9390 | /* filter definition begins */ | |
9391 | if (state == IF_STATE_ACTION) { | |
9392 | filter = perf_addr_filter_new(event, filters); | |
9393 | if (!filter) | |
9394 | goto fail; | |
9395 | } | |
9396 | ||
9397 | token = match_token(start, if_tokens, args); | |
9398 | switch (token) { | |
9399 | case IF_ACT_FILTER: | |
9400 | case IF_ACT_START: | |
375637bc AS |
9401 | case IF_ACT_STOP: |
9402 | if (state != IF_STATE_ACTION) | |
9403 | goto fail; | |
9404 | ||
6ed70cf3 | 9405 | filter->action = actions[token]; |
375637bc AS |
9406 | state = IF_STATE_SOURCE; |
9407 | break; | |
9408 | ||
9409 | case IF_SRC_KERNELADDR: | |
9410 | case IF_SRC_KERNEL: | |
9411 | kernel = 1; | |
10c3405f | 9412 | /* fall through */ |
375637bc AS |
9413 | |
9414 | case IF_SRC_FILEADDR: | |
9415 | case IF_SRC_FILE: | |
9416 | if (state != IF_STATE_SOURCE) | |
9417 | goto fail; | |
9418 | ||
375637bc AS |
9419 | *args[0].to = 0; |
9420 | ret = kstrtoul(args[0].from, 0, &filter->offset); | |
9421 | if (ret) | |
9422 | goto fail; | |
9423 | ||
6ed70cf3 | 9424 | if (token == IF_SRC_KERNEL || token == IF_SRC_FILE) { |
375637bc AS |
9425 | *args[1].to = 0; |
9426 | ret = kstrtoul(args[1].from, 0, &filter->size); | |
9427 | if (ret) | |
9428 | goto fail; | |
9429 | } | |
9430 | ||
4059ffd0 | 9431 | if (token == IF_SRC_FILE || token == IF_SRC_FILEADDR) { |
6ed70cf3 | 9432 | int fpos = token == IF_SRC_FILE ? 2 : 1; |
4059ffd0 MP |
9433 | |
9434 | filename = match_strdup(&args[fpos]); | |
375637bc AS |
9435 | if (!filename) { |
9436 | ret = -ENOMEM; | |
9437 | goto fail; | |
9438 | } | |
9439 | } | |
9440 | ||
9441 | state = IF_STATE_END; | |
9442 | break; | |
9443 | ||
9444 | default: | |
9445 | goto fail; | |
9446 | } | |
9447 | ||
9448 | /* | |
9449 | * Filter definition is fully parsed, validate and install it. | |
9450 | * Make sure that it doesn't contradict itself or the event's | |
9451 | * attribute. | |
9452 | */ | |
9453 | if (state == IF_STATE_END) { | |
9ccbfbb1 | 9454 | ret = -EINVAL; |
375637bc AS |
9455 | if (kernel && event->attr.exclude_kernel) |
9456 | goto fail; | |
9457 | ||
6ed70cf3 AS |
9458 | /* |
9459 | * ACTION "filter" must have a non-zero length region | |
9460 | * specified. | |
9461 | */ | |
9462 | if (filter->action == PERF_ADDR_FILTER_ACTION_FILTER && | |
9463 | !filter->size) | |
9464 | goto fail; | |
9465 | ||
375637bc AS |
9466 | if (!kernel) { |
9467 | if (!filename) | |
9468 | goto fail; | |
9469 | ||
6ce77bfd AS |
9470 | /* |
9471 | * For now, we only support file-based filters | |
9472 | * in per-task events; doing so for CPU-wide | |
9473 | * events requires additional context switching | |
9474 | * trickery, since same object code will be | |
9475 | * mapped at different virtual addresses in | |
9476 | * different processes. | |
9477 | */ | |
9478 | ret = -EOPNOTSUPP; | |
9479 | if (!event->ctx->task) | |
9480 | goto fail_free_name; | |
9481 | ||
375637bc | 9482 | /* look up the path and grab its inode */ |
9511bce9 SL |
9483 | ret = kern_path(filename, LOOKUP_FOLLOW, |
9484 | &filter->path); | |
375637bc AS |
9485 | if (ret) |
9486 | goto fail_free_name; | |
9487 | ||
375637bc AS |
9488 | kfree(filename); |
9489 | filename = NULL; | |
9490 | ||
9491 | ret = -EINVAL; | |
9511bce9 SL |
9492 | if (!filter->path.dentry || |
9493 | !S_ISREG(d_inode(filter->path.dentry) | |
9494 | ->i_mode)) | |
375637bc | 9495 | goto fail; |
6ce77bfd AS |
9496 | |
9497 | event->addr_filters.nr_file_filters++; | |
375637bc AS |
9498 | } |
9499 | ||
9500 | /* ready to consume more filters */ | |
9501 | state = IF_STATE_ACTION; | |
9502 | filter = NULL; | |
9503 | } | |
9504 | } | |
9505 | ||
9506 | if (state != IF_STATE_ACTION) | |
9507 | goto fail; | |
9508 | ||
9509 | kfree(orig); | |
9510 | ||
9511 | return 0; | |
9512 | ||
9513 | fail_free_name: | |
9514 | kfree(filename); | |
9515 | fail: | |
9516 | free_filters_list(filters); | |
9517 | kfree(orig); | |
9518 | ||
9519 | return ret; | |
9520 | } | |
9521 | ||
9522 | static int | |
9523 | perf_event_set_addr_filter(struct perf_event *event, char *filter_str) | |
9524 | { | |
9525 | LIST_HEAD(filters); | |
9526 | int ret; | |
9527 | ||
9528 | /* | |
9529 | * Since this is called in perf_ioctl() path, we're already holding | |
9530 | * ctx::mutex. | |
9531 | */ | |
9532 | lockdep_assert_held(&event->ctx->mutex); | |
9533 | ||
9534 | if (WARN_ON_ONCE(event->parent)) | |
9535 | return -EINVAL; | |
9536 | ||
375637bc AS |
9537 | ret = perf_event_parse_addr_filter(event, filter_str, &filters); |
9538 | if (ret) | |
6ce77bfd | 9539 | goto fail_clear_files; |
375637bc AS |
9540 | |
9541 | ret = event->pmu->addr_filters_validate(&filters); | |
6ce77bfd AS |
9542 | if (ret) |
9543 | goto fail_free_filters; | |
375637bc AS |
9544 | |
9545 | /* remove existing filters, if any */ | |
9546 | perf_addr_filters_splice(event, &filters); | |
9547 | ||
9548 | /* install new filters */ | |
9549 | perf_event_for_each_child(event, perf_event_addr_filters_apply); | |
9550 | ||
6ce77bfd AS |
9551 | return ret; |
9552 | ||
9553 | fail_free_filters: | |
9554 | free_filters_list(&filters); | |
9555 | ||
9556 | fail_clear_files: | |
9557 | event->addr_filters.nr_file_filters = 0; | |
9558 | ||
375637bc AS |
9559 | return ret; |
9560 | } | |
9561 | ||
c796bbbe AS |
9562 | static int perf_event_set_filter(struct perf_event *event, void __user *arg) |
9563 | { | |
c796bbbe | 9564 | int ret = -EINVAL; |
e12f03d7 | 9565 | char *filter_str; |
c796bbbe AS |
9566 | |
9567 | filter_str = strndup_user(arg, PAGE_SIZE); | |
9568 | if (IS_ERR(filter_str)) | |
9569 | return PTR_ERR(filter_str); | |
9570 | ||
e12f03d7 SL |
9571 | #ifdef CONFIG_EVENT_TRACING |
9572 | if (perf_event_is_tracing(event)) { | |
9573 | struct perf_event_context *ctx = event->ctx; | |
9574 | ||
9575 | /* | |
9576 | * Beware, here be dragons!! | |
9577 | * | |
9578 | * the tracepoint muck will deadlock against ctx->mutex, but | |
9579 | * the tracepoint stuff does not actually need it. So | |
9580 | * temporarily drop ctx->mutex. As per perf_event_ctx_lock() we | |
9581 | * already have a reference on ctx. | |
9582 | * | |
9583 | * This can result in event getting moved to a different ctx, | |
9584 | * but that does not affect the tracepoint state. | |
9585 | */ | |
9586 | mutex_unlock(&ctx->mutex); | |
9587 | ret = ftrace_profile_set_filter(event, event->attr.config, filter_str); | |
9588 | mutex_lock(&ctx->mutex); | |
9589 | } else | |
9590 | #endif | |
9591 | if (has_addr_filter(event)) | |
375637bc | 9592 | ret = perf_event_set_addr_filter(event, filter_str); |
c796bbbe AS |
9593 | |
9594 | kfree(filter_str); | |
9595 | return ret; | |
9596 | } | |
9597 | ||
b0a873eb PZ |
9598 | /* |
9599 | * hrtimer based swevent callback | |
9600 | */ | |
f29ac756 | 9601 | |
b0a873eb | 9602 | static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer) |
f29ac756 | 9603 | { |
b0a873eb PZ |
9604 | enum hrtimer_restart ret = HRTIMER_RESTART; |
9605 | struct perf_sample_data data; | |
9606 | struct pt_regs *regs; | |
9607 | struct perf_event *event; | |
9608 | u64 period; | |
f29ac756 | 9609 | |
b0a873eb | 9610 | event = container_of(hrtimer, struct perf_event, hw.hrtimer); |
ba3dd36c PZ |
9611 | |
9612 | if (event->state != PERF_EVENT_STATE_ACTIVE) | |
9613 | return HRTIMER_NORESTART; | |
9614 | ||
b0a873eb | 9615 | event->pmu->read(event); |
f344011c | 9616 | |
fd0d000b | 9617 | perf_sample_data_init(&data, 0, event->hw.last_period); |
b0a873eb PZ |
9618 | regs = get_irq_regs(); |
9619 | ||
9620 | if (regs && !perf_exclude_event(event, regs)) { | |
77aeeebd | 9621 | if (!(event->attr.exclude_idle && is_idle_task(current))) |
33b07b8b | 9622 | if (__perf_event_overflow(event, 1, &data, regs)) |
b0a873eb PZ |
9623 | ret = HRTIMER_NORESTART; |
9624 | } | |
24f1e32c | 9625 | |
b0a873eb PZ |
9626 | period = max_t(u64, 10000, event->hw.sample_period); |
9627 | hrtimer_forward_now(hrtimer, ns_to_ktime(period)); | |
24f1e32c | 9628 | |
b0a873eb | 9629 | return ret; |
f29ac756 PZ |
9630 | } |
9631 | ||
b0a873eb | 9632 | static void perf_swevent_start_hrtimer(struct perf_event *event) |
5c92d124 | 9633 | { |
b0a873eb | 9634 | struct hw_perf_event *hwc = &event->hw; |
5d508e82 FBH |
9635 | s64 period; |
9636 | ||
9637 | if (!is_sampling_event(event)) | |
9638 | return; | |
f5ffe02e | 9639 | |
5d508e82 FBH |
9640 | period = local64_read(&hwc->period_left); |
9641 | if (period) { | |
9642 | if (period < 0) | |
9643 | period = 10000; | |
fa407f35 | 9644 | |
5d508e82 FBH |
9645 | local64_set(&hwc->period_left, 0); |
9646 | } else { | |
9647 | period = max_t(u64, 10000, hwc->sample_period); | |
9648 | } | |
3497d206 | 9649 | hrtimer_start(&hwc->hrtimer, ns_to_ktime(period), |
30f9028b | 9650 | HRTIMER_MODE_REL_PINNED_HARD); |
24f1e32c | 9651 | } |
b0a873eb PZ |
9652 | |
9653 | static void perf_swevent_cancel_hrtimer(struct perf_event *event) | |
24f1e32c | 9654 | { |
b0a873eb PZ |
9655 | struct hw_perf_event *hwc = &event->hw; |
9656 | ||
6c7e550f | 9657 | if (is_sampling_event(event)) { |
b0a873eb | 9658 | ktime_t remaining = hrtimer_get_remaining(&hwc->hrtimer); |
fa407f35 | 9659 | local64_set(&hwc->period_left, ktime_to_ns(remaining)); |
b0a873eb PZ |
9660 | |
9661 | hrtimer_cancel(&hwc->hrtimer); | |
9662 | } | |
24f1e32c FW |
9663 | } |
9664 | ||
ba3dd36c PZ |
9665 | static void perf_swevent_init_hrtimer(struct perf_event *event) |
9666 | { | |
9667 | struct hw_perf_event *hwc = &event->hw; | |
9668 | ||
9669 | if (!is_sampling_event(event)) | |
9670 | return; | |
9671 | ||
30f9028b | 9672 | hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_HARD); |
ba3dd36c PZ |
9673 | hwc->hrtimer.function = perf_swevent_hrtimer; |
9674 | ||
9675 | /* | |
9676 | * Since hrtimers have a fixed rate, we can do a static freq->period | |
9677 | * mapping and avoid the whole period adjust feedback stuff. | |
9678 | */ | |
9679 | if (event->attr.freq) { | |
9680 | long freq = event->attr.sample_freq; | |
9681 | ||
9682 | event->attr.sample_period = NSEC_PER_SEC / freq; | |
9683 | hwc->sample_period = event->attr.sample_period; | |
9684 | local64_set(&hwc->period_left, hwc->sample_period); | |
778141e3 | 9685 | hwc->last_period = hwc->sample_period; |
ba3dd36c PZ |
9686 | event->attr.freq = 0; |
9687 | } | |
9688 | } | |
9689 | ||
b0a873eb PZ |
9690 | /* |
9691 | * Software event: cpu wall time clock | |
9692 | */ | |
9693 | ||
9694 | static void cpu_clock_event_update(struct perf_event *event) | |
24f1e32c | 9695 | { |
b0a873eb PZ |
9696 | s64 prev; |
9697 | u64 now; | |
9698 | ||
a4eaf7f1 | 9699 | now = local_clock(); |
b0a873eb PZ |
9700 | prev = local64_xchg(&event->hw.prev_count, now); |
9701 | local64_add(now - prev, &event->count); | |
24f1e32c | 9702 | } |
24f1e32c | 9703 | |
a4eaf7f1 | 9704 | static void cpu_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 9705 | { |
a4eaf7f1 | 9706 | local64_set(&event->hw.prev_count, local_clock()); |
b0a873eb | 9707 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
9708 | } |
9709 | ||
a4eaf7f1 | 9710 | static void cpu_clock_event_stop(struct perf_event *event, int flags) |
f29ac756 | 9711 | { |
b0a873eb PZ |
9712 | perf_swevent_cancel_hrtimer(event); |
9713 | cpu_clock_event_update(event); | |
9714 | } | |
f29ac756 | 9715 | |
a4eaf7f1 PZ |
9716 | static int cpu_clock_event_add(struct perf_event *event, int flags) |
9717 | { | |
9718 | if (flags & PERF_EF_START) | |
9719 | cpu_clock_event_start(event, flags); | |
6a694a60 | 9720 | perf_event_update_userpage(event); |
a4eaf7f1 PZ |
9721 | |
9722 | return 0; | |
9723 | } | |
9724 | ||
9725 | static void cpu_clock_event_del(struct perf_event *event, int flags) | |
9726 | { | |
9727 | cpu_clock_event_stop(event, flags); | |
9728 | } | |
9729 | ||
b0a873eb PZ |
9730 | static void cpu_clock_event_read(struct perf_event *event) |
9731 | { | |
9732 | cpu_clock_event_update(event); | |
9733 | } | |
f344011c | 9734 | |
b0a873eb PZ |
9735 | static int cpu_clock_event_init(struct perf_event *event) |
9736 | { | |
9737 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
9738 | return -ENOENT; | |
9739 | ||
9740 | if (event->attr.config != PERF_COUNT_SW_CPU_CLOCK) | |
9741 | return -ENOENT; | |
9742 | ||
2481c5fa SE |
9743 | /* |
9744 | * no branch sampling for software events | |
9745 | */ | |
9746 | if (has_branch_stack(event)) | |
9747 | return -EOPNOTSUPP; | |
9748 | ||
ba3dd36c PZ |
9749 | perf_swevent_init_hrtimer(event); |
9750 | ||
b0a873eb | 9751 | return 0; |
f29ac756 PZ |
9752 | } |
9753 | ||
b0a873eb | 9754 | static struct pmu perf_cpu_clock = { |
89a1e187 PZ |
9755 | .task_ctx_nr = perf_sw_context, |
9756 | ||
34f43927 PZ |
9757 | .capabilities = PERF_PMU_CAP_NO_NMI, |
9758 | ||
b0a873eb | 9759 | .event_init = cpu_clock_event_init, |
a4eaf7f1 PZ |
9760 | .add = cpu_clock_event_add, |
9761 | .del = cpu_clock_event_del, | |
9762 | .start = cpu_clock_event_start, | |
9763 | .stop = cpu_clock_event_stop, | |
b0a873eb PZ |
9764 | .read = cpu_clock_event_read, |
9765 | }; | |
9766 | ||
9767 | /* | |
9768 | * Software event: task time clock | |
9769 | */ | |
9770 | ||
9771 | static void task_clock_event_update(struct perf_event *event, u64 now) | |
5c92d124 | 9772 | { |
b0a873eb PZ |
9773 | u64 prev; |
9774 | s64 delta; | |
5c92d124 | 9775 | |
b0a873eb PZ |
9776 | prev = local64_xchg(&event->hw.prev_count, now); |
9777 | delta = now - prev; | |
9778 | local64_add(delta, &event->count); | |
9779 | } | |
5c92d124 | 9780 | |
a4eaf7f1 | 9781 | static void task_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 9782 | { |
a4eaf7f1 | 9783 | local64_set(&event->hw.prev_count, event->ctx->time); |
b0a873eb | 9784 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
9785 | } |
9786 | ||
a4eaf7f1 | 9787 | static void task_clock_event_stop(struct perf_event *event, int flags) |
b0a873eb PZ |
9788 | { |
9789 | perf_swevent_cancel_hrtimer(event); | |
9790 | task_clock_event_update(event, event->ctx->time); | |
a4eaf7f1 PZ |
9791 | } |
9792 | ||
9793 | static int task_clock_event_add(struct perf_event *event, int flags) | |
9794 | { | |
9795 | if (flags & PERF_EF_START) | |
9796 | task_clock_event_start(event, flags); | |
6a694a60 | 9797 | perf_event_update_userpage(event); |
b0a873eb | 9798 | |
a4eaf7f1 PZ |
9799 | return 0; |
9800 | } | |
9801 | ||
9802 | static void task_clock_event_del(struct perf_event *event, int flags) | |
9803 | { | |
9804 | task_clock_event_stop(event, PERF_EF_UPDATE); | |
b0a873eb PZ |
9805 | } |
9806 | ||
9807 | static void task_clock_event_read(struct perf_event *event) | |
9808 | { | |
768a06e2 PZ |
9809 | u64 now = perf_clock(); |
9810 | u64 delta = now - event->ctx->timestamp; | |
9811 | u64 time = event->ctx->time + delta; | |
b0a873eb PZ |
9812 | |
9813 | task_clock_event_update(event, time); | |
9814 | } | |
9815 | ||
9816 | static int task_clock_event_init(struct perf_event *event) | |
6fb2915d | 9817 | { |
b0a873eb PZ |
9818 | if (event->attr.type != PERF_TYPE_SOFTWARE) |
9819 | return -ENOENT; | |
9820 | ||
9821 | if (event->attr.config != PERF_COUNT_SW_TASK_CLOCK) | |
9822 | return -ENOENT; | |
9823 | ||
2481c5fa SE |
9824 | /* |
9825 | * no branch sampling for software events | |
9826 | */ | |
9827 | if (has_branch_stack(event)) | |
9828 | return -EOPNOTSUPP; | |
9829 | ||
ba3dd36c PZ |
9830 | perf_swevent_init_hrtimer(event); |
9831 | ||
b0a873eb | 9832 | return 0; |
6fb2915d LZ |
9833 | } |
9834 | ||
b0a873eb | 9835 | static struct pmu perf_task_clock = { |
89a1e187 PZ |
9836 | .task_ctx_nr = perf_sw_context, |
9837 | ||
34f43927 PZ |
9838 | .capabilities = PERF_PMU_CAP_NO_NMI, |
9839 | ||
b0a873eb | 9840 | .event_init = task_clock_event_init, |
a4eaf7f1 PZ |
9841 | .add = task_clock_event_add, |
9842 | .del = task_clock_event_del, | |
9843 | .start = task_clock_event_start, | |
9844 | .stop = task_clock_event_stop, | |
b0a873eb PZ |
9845 | .read = task_clock_event_read, |
9846 | }; | |
6fb2915d | 9847 | |
ad5133b7 | 9848 | static void perf_pmu_nop_void(struct pmu *pmu) |
e077df4f | 9849 | { |
e077df4f | 9850 | } |
6fb2915d | 9851 | |
fbbe0701 SB |
9852 | static void perf_pmu_nop_txn(struct pmu *pmu, unsigned int flags) |
9853 | { | |
9854 | } | |
9855 | ||
ad5133b7 | 9856 | static int perf_pmu_nop_int(struct pmu *pmu) |
6fb2915d | 9857 | { |
ad5133b7 | 9858 | return 0; |
6fb2915d LZ |
9859 | } |
9860 | ||
81ec3f3c JO |
9861 | static int perf_event_nop_int(struct perf_event *event, u64 value) |
9862 | { | |
9863 | return 0; | |
9864 | } | |
9865 | ||
18ab2cd3 | 9866 | static DEFINE_PER_CPU(unsigned int, nop_txn_flags); |
fbbe0701 SB |
9867 | |
9868 | static void perf_pmu_start_txn(struct pmu *pmu, unsigned int flags) | |
6fb2915d | 9869 | { |
fbbe0701 SB |
9870 | __this_cpu_write(nop_txn_flags, flags); |
9871 | ||
9872 | if (flags & ~PERF_PMU_TXN_ADD) | |
9873 | return; | |
9874 | ||
ad5133b7 | 9875 | perf_pmu_disable(pmu); |
6fb2915d LZ |
9876 | } |
9877 | ||
ad5133b7 PZ |
9878 | static int perf_pmu_commit_txn(struct pmu *pmu) |
9879 | { | |
fbbe0701 SB |
9880 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
9881 | ||
9882 | __this_cpu_write(nop_txn_flags, 0); | |
9883 | ||
9884 | if (flags & ~PERF_PMU_TXN_ADD) | |
9885 | return 0; | |
9886 | ||
ad5133b7 PZ |
9887 | perf_pmu_enable(pmu); |
9888 | return 0; | |
9889 | } | |
e077df4f | 9890 | |
ad5133b7 | 9891 | static void perf_pmu_cancel_txn(struct pmu *pmu) |
24f1e32c | 9892 | { |
fbbe0701 SB |
9893 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
9894 | ||
9895 | __this_cpu_write(nop_txn_flags, 0); | |
9896 | ||
9897 | if (flags & ~PERF_PMU_TXN_ADD) | |
9898 | return; | |
9899 | ||
ad5133b7 | 9900 | perf_pmu_enable(pmu); |
24f1e32c FW |
9901 | } |
9902 | ||
35edc2a5 PZ |
9903 | static int perf_event_idx_default(struct perf_event *event) |
9904 | { | |
c719f560 | 9905 | return 0; |
35edc2a5 PZ |
9906 | } |
9907 | ||
8dc85d54 PZ |
9908 | /* |
9909 | * Ensures all contexts with the same task_ctx_nr have the same | |
9910 | * pmu_cpu_context too. | |
9911 | */ | |
9e317041 | 9912 | static struct perf_cpu_context __percpu *find_pmu_context(int ctxn) |
24f1e32c | 9913 | { |
8dc85d54 | 9914 | struct pmu *pmu; |
b326e956 | 9915 | |
8dc85d54 PZ |
9916 | if (ctxn < 0) |
9917 | return NULL; | |
24f1e32c | 9918 | |
8dc85d54 PZ |
9919 | list_for_each_entry(pmu, &pmus, entry) { |
9920 | if (pmu->task_ctx_nr == ctxn) | |
9921 | return pmu->pmu_cpu_context; | |
9922 | } | |
24f1e32c | 9923 | |
8dc85d54 | 9924 | return NULL; |
24f1e32c FW |
9925 | } |
9926 | ||
51676957 PZ |
9927 | static void free_pmu_context(struct pmu *pmu) |
9928 | { | |
df0062b2 WD |
9929 | /* |
9930 | * Static contexts such as perf_sw_context have a global lifetime | |
9931 | * and may be shared between different PMUs. Avoid freeing them | |
9932 | * when a single PMU is going away. | |
9933 | */ | |
9934 | if (pmu->task_ctx_nr > perf_invalid_context) | |
9935 | return; | |
9936 | ||
51676957 | 9937 | free_percpu(pmu->pmu_cpu_context); |
24f1e32c | 9938 | } |
6e855cd4 AS |
9939 | |
9940 | /* | |
9941 | * Let userspace know that this PMU supports address range filtering: | |
9942 | */ | |
9943 | static ssize_t nr_addr_filters_show(struct device *dev, | |
9944 | struct device_attribute *attr, | |
9945 | char *page) | |
9946 | { | |
9947 | struct pmu *pmu = dev_get_drvdata(dev); | |
9948 | ||
9949 | return snprintf(page, PAGE_SIZE - 1, "%d\n", pmu->nr_addr_filters); | |
9950 | } | |
9951 | DEVICE_ATTR_RO(nr_addr_filters); | |
9952 | ||
2e80a82a | 9953 | static struct idr pmu_idr; |
d6d020e9 | 9954 | |
abe43400 PZ |
9955 | static ssize_t |
9956 | type_show(struct device *dev, struct device_attribute *attr, char *page) | |
9957 | { | |
9958 | struct pmu *pmu = dev_get_drvdata(dev); | |
9959 | ||
9960 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->type); | |
9961 | } | |
90826ca7 | 9962 | static DEVICE_ATTR_RO(type); |
abe43400 | 9963 | |
62b85639 SE |
9964 | static ssize_t |
9965 | perf_event_mux_interval_ms_show(struct device *dev, | |
9966 | struct device_attribute *attr, | |
9967 | char *page) | |
9968 | { | |
9969 | struct pmu *pmu = dev_get_drvdata(dev); | |
9970 | ||
9971 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->hrtimer_interval_ms); | |
9972 | } | |
9973 | ||
272325c4 PZ |
9974 | static DEFINE_MUTEX(mux_interval_mutex); |
9975 | ||
62b85639 SE |
9976 | static ssize_t |
9977 | perf_event_mux_interval_ms_store(struct device *dev, | |
9978 | struct device_attribute *attr, | |
9979 | const char *buf, size_t count) | |
9980 | { | |
9981 | struct pmu *pmu = dev_get_drvdata(dev); | |
9982 | int timer, cpu, ret; | |
9983 | ||
9984 | ret = kstrtoint(buf, 0, &timer); | |
9985 | if (ret) | |
9986 | return ret; | |
9987 | ||
9988 | if (timer < 1) | |
9989 | return -EINVAL; | |
9990 | ||
9991 | /* same value, noting to do */ | |
9992 | if (timer == pmu->hrtimer_interval_ms) | |
9993 | return count; | |
9994 | ||
272325c4 | 9995 | mutex_lock(&mux_interval_mutex); |
62b85639 SE |
9996 | pmu->hrtimer_interval_ms = timer; |
9997 | ||
9998 | /* update all cpuctx for this PMU */ | |
a63fbed7 | 9999 | cpus_read_lock(); |
272325c4 | 10000 | for_each_online_cpu(cpu) { |
62b85639 SE |
10001 | struct perf_cpu_context *cpuctx; |
10002 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
10003 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * timer); | |
10004 | ||
272325c4 PZ |
10005 | cpu_function_call(cpu, |
10006 | (remote_function_f)perf_mux_hrtimer_restart, cpuctx); | |
62b85639 | 10007 | } |
a63fbed7 | 10008 | cpus_read_unlock(); |
272325c4 | 10009 | mutex_unlock(&mux_interval_mutex); |
62b85639 SE |
10010 | |
10011 | return count; | |
10012 | } | |
90826ca7 | 10013 | static DEVICE_ATTR_RW(perf_event_mux_interval_ms); |
62b85639 | 10014 | |
90826ca7 GKH |
10015 | static struct attribute *pmu_dev_attrs[] = { |
10016 | &dev_attr_type.attr, | |
10017 | &dev_attr_perf_event_mux_interval_ms.attr, | |
10018 | NULL, | |
abe43400 | 10019 | }; |
90826ca7 | 10020 | ATTRIBUTE_GROUPS(pmu_dev); |
abe43400 PZ |
10021 | |
10022 | static int pmu_bus_running; | |
10023 | static struct bus_type pmu_bus = { | |
10024 | .name = "event_source", | |
90826ca7 | 10025 | .dev_groups = pmu_dev_groups, |
abe43400 PZ |
10026 | }; |
10027 | ||
10028 | static void pmu_dev_release(struct device *dev) | |
10029 | { | |
10030 | kfree(dev); | |
10031 | } | |
10032 | ||
10033 | static int pmu_dev_alloc(struct pmu *pmu) | |
10034 | { | |
10035 | int ret = -ENOMEM; | |
10036 | ||
10037 | pmu->dev = kzalloc(sizeof(struct device), GFP_KERNEL); | |
10038 | if (!pmu->dev) | |
10039 | goto out; | |
10040 | ||
0c9d42ed | 10041 | pmu->dev->groups = pmu->attr_groups; |
abe43400 PZ |
10042 | device_initialize(pmu->dev); |
10043 | ret = dev_set_name(pmu->dev, "%s", pmu->name); | |
10044 | if (ret) | |
10045 | goto free_dev; | |
10046 | ||
10047 | dev_set_drvdata(pmu->dev, pmu); | |
10048 | pmu->dev->bus = &pmu_bus; | |
10049 | pmu->dev->release = pmu_dev_release; | |
10050 | ret = device_add(pmu->dev); | |
10051 | if (ret) | |
10052 | goto free_dev; | |
10053 | ||
6e855cd4 AS |
10054 | /* For PMUs with address filters, throw in an extra attribute: */ |
10055 | if (pmu->nr_addr_filters) | |
10056 | ret = device_create_file(pmu->dev, &dev_attr_nr_addr_filters); | |
10057 | ||
10058 | if (ret) | |
10059 | goto del_dev; | |
10060 | ||
f3a3a825 JO |
10061 | if (pmu->attr_update) |
10062 | ret = sysfs_update_groups(&pmu->dev->kobj, pmu->attr_update); | |
10063 | ||
10064 | if (ret) | |
10065 | goto del_dev; | |
10066 | ||
abe43400 PZ |
10067 | out: |
10068 | return ret; | |
10069 | ||
6e855cd4 AS |
10070 | del_dev: |
10071 | device_del(pmu->dev); | |
10072 | ||
abe43400 PZ |
10073 | free_dev: |
10074 | put_device(pmu->dev); | |
10075 | goto out; | |
10076 | } | |
10077 | ||
547e9fd7 | 10078 | static struct lock_class_key cpuctx_mutex; |
facc4307 | 10079 | static struct lock_class_key cpuctx_lock; |
547e9fd7 | 10080 | |
03d8e80b | 10081 | int perf_pmu_register(struct pmu *pmu, const char *name, int type) |
24f1e32c | 10082 | { |
66d258c5 | 10083 | int cpu, ret, max = PERF_TYPE_MAX; |
24f1e32c | 10084 | |
b0a873eb | 10085 | mutex_lock(&pmus_lock); |
33696fc0 PZ |
10086 | ret = -ENOMEM; |
10087 | pmu->pmu_disable_count = alloc_percpu(int); | |
10088 | if (!pmu->pmu_disable_count) | |
10089 | goto unlock; | |
f29ac756 | 10090 | |
2e80a82a PZ |
10091 | pmu->type = -1; |
10092 | if (!name) | |
10093 | goto skip_type; | |
10094 | pmu->name = name; | |
10095 | ||
66d258c5 PZ |
10096 | if (type != PERF_TYPE_SOFTWARE) { |
10097 | if (type >= 0) | |
10098 | max = type; | |
10099 | ||
10100 | ret = idr_alloc(&pmu_idr, pmu, max, 0, GFP_KERNEL); | |
10101 | if (ret < 0) | |
2e80a82a | 10102 | goto free_pdc; |
66d258c5 PZ |
10103 | |
10104 | WARN_ON(type >= 0 && ret != type); | |
10105 | ||
10106 | type = ret; | |
2e80a82a PZ |
10107 | } |
10108 | pmu->type = type; | |
10109 | ||
abe43400 PZ |
10110 | if (pmu_bus_running) { |
10111 | ret = pmu_dev_alloc(pmu); | |
10112 | if (ret) | |
10113 | goto free_idr; | |
10114 | } | |
10115 | ||
2e80a82a | 10116 | skip_type: |
26657848 PZ |
10117 | if (pmu->task_ctx_nr == perf_hw_context) { |
10118 | static int hw_context_taken = 0; | |
10119 | ||
5101ef20 MR |
10120 | /* |
10121 | * Other than systems with heterogeneous CPUs, it never makes | |
10122 | * sense for two PMUs to share perf_hw_context. PMUs which are | |
10123 | * uncore must use perf_invalid_context. | |
10124 | */ | |
10125 | if (WARN_ON_ONCE(hw_context_taken && | |
10126 | !(pmu->capabilities & PERF_PMU_CAP_HETEROGENEOUS_CPUS))) | |
26657848 PZ |
10127 | pmu->task_ctx_nr = perf_invalid_context; |
10128 | ||
10129 | hw_context_taken = 1; | |
10130 | } | |
10131 | ||
8dc85d54 PZ |
10132 | pmu->pmu_cpu_context = find_pmu_context(pmu->task_ctx_nr); |
10133 | if (pmu->pmu_cpu_context) | |
10134 | goto got_cpu_context; | |
f29ac756 | 10135 | |
c4814202 | 10136 | ret = -ENOMEM; |
108b02cf PZ |
10137 | pmu->pmu_cpu_context = alloc_percpu(struct perf_cpu_context); |
10138 | if (!pmu->pmu_cpu_context) | |
abe43400 | 10139 | goto free_dev; |
f344011c | 10140 | |
108b02cf PZ |
10141 | for_each_possible_cpu(cpu) { |
10142 | struct perf_cpu_context *cpuctx; | |
10143 | ||
10144 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
eb184479 | 10145 | __perf_event_init_context(&cpuctx->ctx); |
547e9fd7 | 10146 | lockdep_set_class(&cpuctx->ctx.mutex, &cpuctx_mutex); |
facc4307 | 10147 | lockdep_set_class(&cpuctx->ctx.lock, &cpuctx_lock); |
108b02cf | 10148 | cpuctx->ctx.pmu = pmu; |
a63fbed7 | 10149 | cpuctx->online = cpumask_test_cpu(cpu, perf_online_mask); |
9e630205 | 10150 | |
272325c4 | 10151 | __perf_mux_hrtimer_init(cpuctx, cpu); |
108b02cf | 10152 | } |
76e1d904 | 10153 | |
8dc85d54 | 10154 | got_cpu_context: |
ad5133b7 PZ |
10155 | if (!pmu->start_txn) { |
10156 | if (pmu->pmu_enable) { | |
10157 | /* | |
10158 | * If we have pmu_enable/pmu_disable calls, install | |
10159 | * transaction stubs that use that to try and batch | |
10160 | * hardware accesses. | |
10161 | */ | |
10162 | pmu->start_txn = perf_pmu_start_txn; | |
10163 | pmu->commit_txn = perf_pmu_commit_txn; | |
10164 | pmu->cancel_txn = perf_pmu_cancel_txn; | |
10165 | } else { | |
fbbe0701 | 10166 | pmu->start_txn = perf_pmu_nop_txn; |
ad5133b7 PZ |
10167 | pmu->commit_txn = perf_pmu_nop_int; |
10168 | pmu->cancel_txn = perf_pmu_nop_void; | |
f344011c | 10169 | } |
5c92d124 | 10170 | } |
15dbf27c | 10171 | |
ad5133b7 PZ |
10172 | if (!pmu->pmu_enable) { |
10173 | pmu->pmu_enable = perf_pmu_nop_void; | |
10174 | pmu->pmu_disable = perf_pmu_nop_void; | |
10175 | } | |
10176 | ||
81ec3f3c JO |
10177 | if (!pmu->check_period) |
10178 | pmu->check_period = perf_event_nop_int; | |
10179 | ||
35edc2a5 PZ |
10180 | if (!pmu->event_idx) |
10181 | pmu->event_idx = perf_event_idx_default; | |
10182 | ||
d44f821b LK |
10183 | /* |
10184 | * Ensure the TYPE_SOFTWARE PMUs are at the head of the list, | |
10185 | * since these cannot be in the IDR. This way the linear search | |
10186 | * is fast, provided a valid software event is provided. | |
10187 | */ | |
10188 | if (type == PERF_TYPE_SOFTWARE || !name) | |
10189 | list_add_rcu(&pmu->entry, &pmus); | |
10190 | else | |
10191 | list_add_tail_rcu(&pmu->entry, &pmus); | |
10192 | ||
bed5b25a | 10193 | atomic_set(&pmu->exclusive_cnt, 0); |
33696fc0 PZ |
10194 | ret = 0; |
10195 | unlock: | |
b0a873eb PZ |
10196 | mutex_unlock(&pmus_lock); |
10197 | ||
33696fc0 | 10198 | return ret; |
108b02cf | 10199 | |
abe43400 PZ |
10200 | free_dev: |
10201 | device_del(pmu->dev); | |
10202 | put_device(pmu->dev); | |
10203 | ||
2e80a82a | 10204 | free_idr: |
66d258c5 | 10205 | if (pmu->type != PERF_TYPE_SOFTWARE) |
2e80a82a PZ |
10206 | idr_remove(&pmu_idr, pmu->type); |
10207 | ||
108b02cf PZ |
10208 | free_pdc: |
10209 | free_percpu(pmu->pmu_disable_count); | |
10210 | goto unlock; | |
f29ac756 | 10211 | } |
c464c76e | 10212 | EXPORT_SYMBOL_GPL(perf_pmu_register); |
f29ac756 | 10213 | |
b0a873eb | 10214 | void perf_pmu_unregister(struct pmu *pmu) |
5c92d124 | 10215 | { |
b0a873eb PZ |
10216 | mutex_lock(&pmus_lock); |
10217 | list_del_rcu(&pmu->entry); | |
5c92d124 | 10218 | |
0475f9ea | 10219 | /* |
cde8e884 PZ |
10220 | * We dereference the pmu list under both SRCU and regular RCU, so |
10221 | * synchronize against both of those. | |
0475f9ea | 10222 | */ |
b0a873eb | 10223 | synchronize_srcu(&pmus_srcu); |
cde8e884 | 10224 | synchronize_rcu(); |
d6d020e9 | 10225 | |
33696fc0 | 10226 | free_percpu(pmu->pmu_disable_count); |
66d258c5 | 10227 | if (pmu->type != PERF_TYPE_SOFTWARE) |
2e80a82a | 10228 | idr_remove(&pmu_idr, pmu->type); |
a9f97721 | 10229 | if (pmu_bus_running) { |
0933840a JO |
10230 | if (pmu->nr_addr_filters) |
10231 | device_remove_file(pmu->dev, &dev_attr_nr_addr_filters); | |
10232 | device_del(pmu->dev); | |
10233 | put_device(pmu->dev); | |
10234 | } | |
51676957 | 10235 | free_pmu_context(pmu); |
a9f97721 | 10236 | mutex_unlock(&pmus_lock); |
b0a873eb | 10237 | } |
c464c76e | 10238 | EXPORT_SYMBOL_GPL(perf_pmu_unregister); |
d6d020e9 | 10239 | |
e321d02d KL |
10240 | static inline bool has_extended_regs(struct perf_event *event) |
10241 | { | |
10242 | return (event->attr.sample_regs_user & PERF_REG_EXTENDED_MASK) || | |
10243 | (event->attr.sample_regs_intr & PERF_REG_EXTENDED_MASK); | |
10244 | } | |
10245 | ||
cc34b98b MR |
10246 | static int perf_try_init_event(struct pmu *pmu, struct perf_event *event) |
10247 | { | |
ccd41c86 | 10248 | struct perf_event_context *ctx = NULL; |
cc34b98b MR |
10249 | int ret; |
10250 | ||
10251 | if (!try_module_get(pmu->module)) | |
10252 | return -ENODEV; | |
ccd41c86 | 10253 | |
0c7296ca PZ |
10254 | /* |
10255 | * A number of pmu->event_init() methods iterate the sibling_list to, | |
10256 | * for example, validate if the group fits on the PMU. Therefore, | |
10257 | * if this is a sibling event, acquire the ctx->mutex to protect | |
10258 | * the sibling_list. | |
10259 | */ | |
10260 | if (event->group_leader != event && pmu->task_ctx_nr != perf_sw_context) { | |
8b10c5e2 PZ |
10261 | /* |
10262 | * This ctx->mutex can nest when we're called through | |
10263 | * inheritance. See the perf_event_ctx_lock_nested() comment. | |
10264 | */ | |
10265 | ctx = perf_event_ctx_lock_nested(event->group_leader, | |
10266 | SINGLE_DEPTH_NESTING); | |
ccd41c86 PZ |
10267 | BUG_ON(!ctx); |
10268 | } | |
10269 | ||
cc34b98b MR |
10270 | event->pmu = pmu; |
10271 | ret = pmu->event_init(event); | |
ccd41c86 PZ |
10272 | |
10273 | if (ctx) | |
10274 | perf_event_ctx_unlock(event->group_leader, ctx); | |
10275 | ||
cc6795ae | 10276 | if (!ret) { |
e321d02d KL |
10277 | if (!(pmu->capabilities & PERF_PMU_CAP_EXTENDED_REGS) && |
10278 | has_extended_regs(event)) | |
10279 | ret = -EOPNOTSUPP; | |
10280 | ||
cc6795ae | 10281 | if (pmu->capabilities & PERF_PMU_CAP_NO_EXCLUDE && |
e321d02d | 10282 | event_has_any_exclude_flag(event)) |
cc6795ae | 10283 | ret = -EINVAL; |
e321d02d KL |
10284 | |
10285 | if (ret && event->destroy) | |
10286 | event->destroy(event); | |
cc6795ae AM |
10287 | } |
10288 | ||
cc34b98b MR |
10289 | if (ret) |
10290 | module_put(pmu->module); | |
10291 | ||
10292 | return ret; | |
10293 | } | |
10294 | ||
18ab2cd3 | 10295 | static struct pmu *perf_init_event(struct perf_event *event) |
b0a873eb | 10296 | { |
66d258c5 | 10297 | int idx, type, ret; |
85c617ab | 10298 | struct pmu *pmu; |
b0a873eb PZ |
10299 | |
10300 | idx = srcu_read_lock(&pmus_srcu); | |
2e80a82a | 10301 | |
40999312 KL |
10302 | /* Try parent's PMU first: */ |
10303 | if (event->parent && event->parent->pmu) { | |
10304 | pmu = event->parent->pmu; | |
10305 | ret = perf_try_init_event(pmu, event); | |
10306 | if (!ret) | |
10307 | goto unlock; | |
10308 | } | |
10309 | ||
66d258c5 PZ |
10310 | /* |
10311 | * PERF_TYPE_HARDWARE and PERF_TYPE_HW_CACHE | |
10312 | * are often aliases for PERF_TYPE_RAW. | |
10313 | */ | |
10314 | type = event->attr.type; | |
10315 | if (type == PERF_TYPE_HARDWARE || type == PERF_TYPE_HW_CACHE) | |
10316 | type = PERF_TYPE_RAW; | |
10317 | ||
10318 | again: | |
deb0c3c2 | 10319 | rcu_read_lock(); |
66d258c5 | 10320 | pmu = idr_find(&pmu_idr, type); |
2e80a82a | 10321 | rcu_read_unlock(); |
940c5b29 | 10322 | if (pmu) { |
cc34b98b | 10323 | ret = perf_try_init_event(pmu, event); |
66d258c5 PZ |
10324 | if (ret == -ENOENT && event->attr.type != type) { |
10325 | type = event->attr.type; | |
10326 | goto again; | |
10327 | } | |
10328 | ||
940c5b29 LM |
10329 | if (ret) |
10330 | pmu = ERR_PTR(ret); | |
66d258c5 | 10331 | |
2e80a82a | 10332 | goto unlock; |
940c5b29 | 10333 | } |
2e80a82a | 10334 | |
b0a873eb | 10335 | list_for_each_entry_rcu(pmu, &pmus, entry) { |
cc34b98b | 10336 | ret = perf_try_init_event(pmu, event); |
b0a873eb | 10337 | if (!ret) |
e5f4d339 | 10338 | goto unlock; |
76e1d904 | 10339 | |
b0a873eb PZ |
10340 | if (ret != -ENOENT) { |
10341 | pmu = ERR_PTR(ret); | |
e5f4d339 | 10342 | goto unlock; |
f344011c | 10343 | } |
5c92d124 | 10344 | } |
e5f4d339 PZ |
10345 | pmu = ERR_PTR(-ENOENT); |
10346 | unlock: | |
b0a873eb | 10347 | srcu_read_unlock(&pmus_srcu, idx); |
15dbf27c | 10348 | |
4aeb0b42 | 10349 | return pmu; |
5c92d124 IM |
10350 | } |
10351 | ||
f2fb6bef KL |
10352 | static void attach_sb_event(struct perf_event *event) |
10353 | { | |
10354 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
10355 | ||
10356 | raw_spin_lock(&pel->lock); | |
10357 | list_add_rcu(&event->sb_list, &pel->list); | |
10358 | raw_spin_unlock(&pel->lock); | |
10359 | } | |
10360 | ||
aab5b71e PZ |
10361 | /* |
10362 | * We keep a list of all !task (and therefore per-cpu) events | |
10363 | * that need to receive side-band records. | |
10364 | * | |
10365 | * This avoids having to scan all the various PMU per-cpu contexts | |
10366 | * looking for them. | |
10367 | */ | |
f2fb6bef KL |
10368 | static void account_pmu_sb_event(struct perf_event *event) |
10369 | { | |
a4f144eb | 10370 | if (is_sb_event(event)) |
f2fb6bef KL |
10371 | attach_sb_event(event); |
10372 | } | |
10373 | ||
4beb31f3 FW |
10374 | static void account_event_cpu(struct perf_event *event, int cpu) |
10375 | { | |
10376 | if (event->parent) | |
10377 | return; | |
10378 | ||
4beb31f3 FW |
10379 | if (is_cgroup_event(event)) |
10380 | atomic_inc(&per_cpu(perf_cgroup_events, cpu)); | |
10381 | } | |
10382 | ||
555e0c1e FW |
10383 | /* Freq events need the tick to stay alive (see perf_event_task_tick). */ |
10384 | static void account_freq_event_nohz(void) | |
10385 | { | |
10386 | #ifdef CONFIG_NO_HZ_FULL | |
10387 | /* Lock so we don't race with concurrent unaccount */ | |
10388 | spin_lock(&nr_freq_lock); | |
10389 | if (atomic_inc_return(&nr_freq_events) == 1) | |
10390 | tick_nohz_dep_set(TICK_DEP_BIT_PERF_EVENTS); | |
10391 | spin_unlock(&nr_freq_lock); | |
10392 | #endif | |
10393 | } | |
10394 | ||
10395 | static void account_freq_event(void) | |
10396 | { | |
10397 | if (tick_nohz_full_enabled()) | |
10398 | account_freq_event_nohz(); | |
10399 | else | |
10400 | atomic_inc(&nr_freq_events); | |
10401 | } | |
10402 | ||
10403 | ||
766d6c07 FW |
10404 | static void account_event(struct perf_event *event) |
10405 | { | |
25432ae9 PZ |
10406 | bool inc = false; |
10407 | ||
4beb31f3 FW |
10408 | if (event->parent) |
10409 | return; | |
10410 | ||
766d6c07 | 10411 | if (event->attach_state & PERF_ATTACH_TASK) |
25432ae9 | 10412 | inc = true; |
766d6c07 FW |
10413 | if (event->attr.mmap || event->attr.mmap_data) |
10414 | atomic_inc(&nr_mmap_events); | |
10415 | if (event->attr.comm) | |
10416 | atomic_inc(&nr_comm_events); | |
e4222673 HB |
10417 | if (event->attr.namespaces) |
10418 | atomic_inc(&nr_namespaces_events); | |
766d6c07 FW |
10419 | if (event->attr.task) |
10420 | atomic_inc(&nr_task_events); | |
555e0c1e FW |
10421 | if (event->attr.freq) |
10422 | account_freq_event(); | |
45ac1403 AH |
10423 | if (event->attr.context_switch) { |
10424 | atomic_inc(&nr_switch_events); | |
25432ae9 | 10425 | inc = true; |
45ac1403 | 10426 | } |
4beb31f3 | 10427 | if (has_branch_stack(event)) |
25432ae9 | 10428 | inc = true; |
4beb31f3 | 10429 | if (is_cgroup_event(event)) |
25432ae9 | 10430 | inc = true; |
76193a94 SL |
10431 | if (event->attr.ksymbol) |
10432 | atomic_inc(&nr_ksymbol_events); | |
6ee52e2a SL |
10433 | if (event->attr.bpf_event) |
10434 | atomic_inc(&nr_bpf_events); | |
25432ae9 | 10435 | |
9107c89e | 10436 | if (inc) { |
5bce9db1 AS |
10437 | /* |
10438 | * We need the mutex here because static_branch_enable() | |
10439 | * must complete *before* the perf_sched_count increment | |
10440 | * becomes visible. | |
10441 | */ | |
9107c89e PZ |
10442 | if (atomic_inc_not_zero(&perf_sched_count)) |
10443 | goto enabled; | |
10444 | ||
10445 | mutex_lock(&perf_sched_mutex); | |
10446 | if (!atomic_read(&perf_sched_count)) { | |
10447 | static_branch_enable(&perf_sched_events); | |
10448 | /* | |
10449 | * Guarantee that all CPUs observe they key change and | |
10450 | * call the perf scheduling hooks before proceeding to | |
10451 | * install events that need them. | |
10452 | */ | |
0809d954 | 10453 | synchronize_rcu(); |
9107c89e PZ |
10454 | } |
10455 | /* | |
10456 | * Now that we have waited for the sync_sched(), allow further | |
10457 | * increments to by-pass the mutex. | |
10458 | */ | |
10459 | atomic_inc(&perf_sched_count); | |
10460 | mutex_unlock(&perf_sched_mutex); | |
10461 | } | |
10462 | enabled: | |
4beb31f3 FW |
10463 | |
10464 | account_event_cpu(event, event->cpu); | |
f2fb6bef KL |
10465 | |
10466 | account_pmu_sb_event(event); | |
766d6c07 FW |
10467 | } |
10468 | ||
0793a61d | 10469 | /* |
788faab7 | 10470 | * Allocate and initialize an event structure |
0793a61d | 10471 | */ |
cdd6c482 | 10472 | static struct perf_event * |
c3f00c70 | 10473 | perf_event_alloc(struct perf_event_attr *attr, int cpu, |
d580ff86 PZ |
10474 | struct task_struct *task, |
10475 | struct perf_event *group_leader, | |
10476 | struct perf_event *parent_event, | |
4dc0da86 | 10477 | perf_overflow_handler_t overflow_handler, |
79dff51e | 10478 | void *context, int cgroup_fd) |
0793a61d | 10479 | { |
51b0fe39 | 10480 | struct pmu *pmu; |
cdd6c482 IM |
10481 | struct perf_event *event; |
10482 | struct hw_perf_event *hwc; | |
90983b16 | 10483 | long err = -EINVAL; |
0793a61d | 10484 | |
66832eb4 ON |
10485 | if ((unsigned)cpu >= nr_cpu_ids) { |
10486 | if (!task || cpu != -1) | |
10487 | return ERR_PTR(-EINVAL); | |
10488 | } | |
10489 | ||
c3f00c70 | 10490 | event = kzalloc(sizeof(*event), GFP_KERNEL); |
cdd6c482 | 10491 | if (!event) |
d5d2bc0d | 10492 | return ERR_PTR(-ENOMEM); |
0793a61d | 10493 | |
04289bb9 | 10494 | /* |
cdd6c482 | 10495 | * Single events are their own group leaders, with an |
04289bb9 IM |
10496 | * empty sibling list: |
10497 | */ | |
10498 | if (!group_leader) | |
cdd6c482 | 10499 | group_leader = event; |
04289bb9 | 10500 | |
cdd6c482 IM |
10501 | mutex_init(&event->child_mutex); |
10502 | INIT_LIST_HEAD(&event->child_list); | |
fccc714b | 10503 | |
cdd6c482 IM |
10504 | INIT_LIST_HEAD(&event->event_entry); |
10505 | INIT_LIST_HEAD(&event->sibling_list); | |
6668128a | 10506 | INIT_LIST_HEAD(&event->active_list); |
8e1a2031 | 10507 | init_event_group(event); |
10c6db11 | 10508 | INIT_LIST_HEAD(&event->rb_entry); |
71ad88ef | 10509 | INIT_LIST_HEAD(&event->active_entry); |
375637bc | 10510 | INIT_LIST_HEAD(&event->addr_filters.list); |
f3ae75de SE |
10511 | INIT_HLIST_NODE(&event->hlist_entry); |
10512 | ||
10c6db11 | 10513 | |
cdd6c482 | 10514 | init_waitqueue_head(&event->waitq); |
1d54ad94 | 10515 | event->pending_disable = -1; |
e360adbe | 10516 | init_irq_work(&event->pending, perf_pending_event); |
0793a61d | 10517 | |
cdd6c482 | 10518 | mutex_init(&event->mmap_mutex); |
375637bc | 10519 | raw_spin_lock_init(&event->addr_filters.lock); |
7b732a75 | 10520 | |
a6fa941d | 10521 | atomic_long_set(&event->refcount, 1); |
cdd6c482 IM |
10522 | event->cpu = cpu; |
10523 | event->attr = *attr; | |
10524 | event->group_leader = group_leader; | |
10525 | event->pmu = NULL; | |
cdd6c482 | 10526 | event->oncpu = -1; |
a96bbc16 | 10527 | |
cdd6c482 | 10528 | event->parent = parent_event; |
b84fbc9f | 10529 | |
17cf22c3 | 10530 | event->ns = get_pid_ns(task_active_pid_ns(current)); |
cdd6c482 | 10531 | event->id = atomic64_inc_return(&perf_event_id); |
a96bbc16 | 10532 | |
cdd6c482 | 10533 | event->state = PERF_EVENT_STATE_INACTIVE; |
329d876d | 10534 | |
d580ff86 PZ |
10535 | if (task) { |
10536 | event->attach_state = PERF_ATTACH_TASK; | |
d580ff86 | 10537 | /* |
50f16a8b PZ |
10538 | * XXX pmu::event_init needs to know what task to account to |
10539 | * and we cannot use the ctx information because we need the | |
10540 | * pmu before we get a ctx. | |
d580ff86 | 10541 | */ |
7b3c92b8 | 10542 | event->hw.target = get_task_struct(task); |
d580ff86 PZ |
10543 | } |
10544 | ||
34f43927 PZ |
10545 | event->clock = &local_clock; |
10546 | if (parent_event) | |
10547 | event->clock = parent_event->clock; | |
10548 | ||
4dc0da86 | 10549 | if (!overflow_handler && parent_event) { |
b326e956 | 10550 | overflow_handler = parent_event->overflow_handler; |
4dc0da86 | 10551 | context = parent_event->overflow_handler_context; |
f1e4ba5b | 10552 | #if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_EVENT_TRACING) |
aa6a5f3c AS |
10553 | if (overflow_handler == bpf_overflow_handler) { |
10554 | struct bpf_prog *prog = bpf_prog_inc(parent_event->prog); | |
10555 | ||
10556 | if (IS_ERR(prog)) { | |
10557 | err = PTR_ERR(prog); | |
10558 | goto err_ns; | |
10559 | } | |
10560 | event->prog = prog; | |
10561 | event->orig_overflow_handler = | |
10562 | parent_event->orig_overflow_handler; | |
10563 | } | |
10564 | #endif | |
4dc0da86 | 10565 | } |
66832eb4 | 10566 | |
1879445d WN |
10567 | if (overflow_handler) { |
10568 | event->overflow_handler = overflow_handler; | |
10569 | event->overflow_handler_context = context; | |
9ecda41a WN |
10570 | } else if (is_write_backward(event)){ |
10571 | event->overflow_handler = perf_event_output_backward; | |
10572 | event->overflow_handler_context = NULL; | |
1879445d | 10573 | } else { |
9ecda41a | 10574 | event->overflow_handler = perf_event_output_forward; |
1879445d WN |
10575 | event->overflow_handler_context = NULL; |
10576 | } | |
97eaf530 | 10577 | |
0231bb53 | 10578 | perf_event__state_init(event); |
a86ed508 | 10579 | |
4aeb0b42 | 10580 | pmu = NULL; |
b8e83514 | 10581 | |
cdd6c482 | 10582 | hwc = &event->hw; |
bd2b5b12 | 10583 | hwc->sample_period = attr->sample_period; |
0d48696f | 10584 | if (attr->freq && attr->sample_freq) |
bd2b5b12 | 10585 | hwc->sample_period = 1; |
eced1dfc | 10586 | hwc->last_period = hwc->sample_period; |
bd2b5b12 | 10587 | |
e7850595 | 10588 | local64_set(&hwc->period_left, hwc->sample_period); |
60db5e09 | 10589 | |
2023b359 | 10590 | /* |
ba5213ae PZ |
10591 | * We currently do not support PERF_SAMPLE_READ on inherited events. |
10592 | * See perf_output_read(). | |
2023b359 | 10593 | */ |
ba5213ae | 10594 | if (attr->inherit && (attr->sample_type & PERF_SAMPLE_READ)) |
90983b16 | 10595 | goto err_ns; |
a46a2300 YZ |
10596 | |
10597 | if (!has_branch_stack(event)) | |
10598 | event->attr.branch_sample_type = 0; | |
2023b359 | 10599 | |
79dff51e MF |
10600 | if (cgroup_fd != -1) { |
10601 | err = perf_cgroup_connect(cgroup_fd, event, attr, group_leader); | |
10602 | if (err) | |
10603 | goto err_ns; | |
10604 | } | |
10605 | ||
b0a873eb | 10606 | pmu = perf_init_event(event); |
85c617ab | 10607 | if (IS_ERR(pmu)) { |
4aeb0b42 | 10608 | err = PTR_ERR(pmu); |
90983b16 | 10609 | goto err_ns; |
621a01ea | 10610 | } |
d5d2bc0d | 10611 | |
09f4e8f0 PZ |
10612 | /* |
10613 | * Disallow uncore-cgroup events, they don't make sense as the cgroup will | |
10614 | * be different on other CPUs in the uncore mask. | |
10615 | */ | |
10616 | if (pmu->task_ctx_nr == perf_invalid_context && cgroup_fd != -1) { | |
10617 | err = -EINVAL; | |
10618 | goto err_pmu; | |
10619 | } | |
10620 | ||
ab43762e AS |
10621 | if (event->attr.aux_output && |
10622 | !(pmu->capabilities & PERF_PMU_CAP_AUX_OUTPUT)) { | |
10623 | err = -EOPNOTSUPP; | |
10624 | goto err_pmu; | |
10625 | } | |
10626 | ||
bed5b25a AS |
10627 | err = exclusive_event_init(event); |
10628 | if (err) | |
10629 | goto err_pmu; | |
10630 | ||
375637bc | 10631 | if (has_addr_filter(event)) { |
c60f83b8 AS |
10632 | event->addr_filter_ranges = kcalloc(pmu->nr_addr_filters, |
10633 | sizeof(struct perf_addr_filter_range), | |
10634 | GFP_KERNEL); | |
10635 | if (!event->addr_filter_ranges) { | |
36cc2b92 | 10636 | err = -ENOMEM; |
375637bc | 10637 | goto err_per_task; |
36cc2b92 | 10638 | } |
375637bc | 10639 | |
18736eef AS |
10640 | /* |
10641 | * Clone the parent's vma offsets: they are valid until exec() | |
10642 | * even if the mm is not shared with the parent. | |
10643 | */ | |
10644 | if (event->parent) { | |
10645 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
10646 | ||
10647 | raw_spin_lock_irq(&ifh->lock); | |
c60f83b8 AS |
10648 | memcpy(event->addr_filter_ranges, |
10649 | event->parent->addr_filter_ranges, | |
10650 | pmu->nr_addr_filters * sizeof(struct perf_addr_filter_range)); | |
18736eef AS |
10651 | raw_spin_unlock_irq(&ifh->lock); |
10652 | } | |
10653 | ||
375637bc AS |
10654 | /* force hw sync on the address filters */ |
10655 | event->addr_filters_gen = 1; | |
10656 | } | |
10657 | ||
cdd6c482 | 10658 | if (!event->parent) { |
927c7a9e | 10659 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) { |
97c79a38 | 10660 | err = get_callchain_buffers(attr->sample_max_stack); |
90983b16 | 10661 | if (err) |
375637bc | 10662 | goto err_addr_filters; |
d010b332 | 10663 | } |
f344011c | 10664 | } |
9ee318a7 | 10665 | |
da97e184 JFG |
10666 | err = security_perf_event_alloc(event); |
10667 | if (err) | |
10668 | goto err_callchain_buffer; | |
10669 | ||
927a5570 AS |
10670 | /* symmetric to unaccount_event() in _free_event() */ |
10671 | account_event(event); | |
10672 | ||
cdd6c482 | 10673 | return event; |
90983b16 | 10674 | |
da97e184 JFG |
10675 | err_callchain_buffer: |
10676 | if (!event->parent) { | |
10677 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) | |
10678 | put_callchain_buffers(); | |
10679 | } | |
375637bc | 10680 | err_addr_filters: |
c60f83b8 | 10681 | kfree(event->addr_filter_ranges); |
375637bc | 10682 | |
bed5b25a AS |
10683 | err_per_task: |
10684 | exclusive_event_destroy(event); | |
10685 | ||
90983b16 FW |
10686 | err_pmu: |
10687 | if (event->destroy) | |
10688 | event->destroy(event); | |
c464c76e | 10689 | module_put(pmu->module); |
90983b16 | 10690 | err_ns: |
79dff51e MF |
10691 | if (is_cgroup_event(event)) |
10692 | perf_detach_cgroup(event); | |
90983b16 FW |
10693 | if (event->ns) |
10694 | put_pid_ns(event->ns); | |
621b6d2e PB |
10695 | if (event->hw.target) |
10696 | put_task_struct(event->hw.target); | |
90983b16 FW |
10697 | kfree(event); |
10698 | ||
10699 | return ERR_PTR(err); | |
0793a61d TG |
10700 | } |
10701 | ||
cdd6c482 IM |
10702 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
10703 | struct perf_event_attr *attr) | |
974802ea | 10704 | { |
974802ea | 10705 | u32 size; |
cdf8073d | 10706 | int ret; |
974802ea | 10707 | |
c2ba8f41 | 10708 | /* Zero the full structure, so that a short copy will be nice. */ |
974802ea PZ |
10709 | memset(attr, 0, sizeof(*attr)); |
10710 | ||
10711 | ret = get_user(size, &uattr->size); | |
10712 | if (ret) | |
10713 | return ret; | |
10714 | ||
c2ba8f41 AS |
10715 | /* ABI compatibility quirk: */ |
10716 | if (!size) | |
974802ea | 10717 | size = PERF_ATTR_SIZE_VER0; |
c2ba8f41 | 10718 | if (size < PERF_ATTR_SIZE_VER0 || size > PAGE_SIZE) |
974802ea PZ |
10719 | goto err_size; |
10720 | ||
c2ba8f41 AS |
10721 | ret = copy_struct_from_user(attr, sizeof(*attr), uattr, size); |
10722 | if (ret) { | |
10723 | if (ret == -E2BIG) | |
10724 | goto err_size; | |
10725 | return ret; | |
974802ea PZ |
10726 | } |
10727 | ||
f12f42ac MX |
10728 | attr->size = size; |
10729 | ||
8c7e9756 | 10730 | if (attr->__reserved_1 || attr->__reserved_2) |
974802ea PZ |
10731 | return -EINVAL; |
10732 | ||
10733 | if (attr->sample_type & ~(PERF_SAMPLE_MAX-1)) | |
10734 | return -EINVAL; | |
10735 | ||
10736 | if (attr->read_format & ~(PERF_FORMAT_MAX-1)) | |
10737 | return -EINVAL; | |
10738 | ||
bce38cd5 SE |
10739 | if (attr->sample_type & PERF_SAMPLE_BRANCH_STACK) { |
10740 | u64 mask = attr->branch_sample_type; | |
10741 | ||
10742 | /* only using defined bits */ | |
10743 | if (mask & ~(PERF_SAMPLE_BRANCH_MAX-1)) | |
10744 | return -EINVAL; | |
10745 | ||
10746 | /* at least one branch bit must be set */ | |
10747 | if (!(mask & ~PERF_SAMPLE_BRANCH_PLM_ALL)) | |
10748 | return -EINVAL; | |
10749 | ||
bce38cd5 SE |
10750 | /* propagate priv level, when not set for branch */ |
10751 | if (!(mask & PERF_SAMPLE_BRANCH_PLM_ALL)) { | |
10752 | ||
10753 | /* exclude_kernel checked on syscall entry */ | |
10754 | if (!attr->exclude_kernel) | |
10755 | mask |= PERF_SAMPLE_BRANCH_KERNEL; | |
10756 | ||
10757 | if (!attr->exclude_user) | |
10758 | mask |= PERF_SAMPLE_BRANCH_USER; | |
10759 | ||
10760 | if (!attr->exclude_hv) | |
10761 | mask |= PERF_SAMPLE_BRANCH_HV; | |
10762 | /* | |
10763 | * adjust user setting (for HW filter setup) | |
10764 | */ | |
10765 | attr->branch_sample_type = mask; | |
10766 | } | |
e712209a | 10767 | /* privileged levels capture (kernel, hv): check permissions */ |
da97e184 JFG |
10768 | if (mask & PERF_SAMPLE_BRANCH_PERM_PLM) { |
10769 | ret = perf_allow_kernel(attr); | |
10770 | if (ret) | |
10771 | return ret; | |
10772 | } | |
bce38cd5 | 10773 | } |
4018994f | 10774 | |
c5ebcedb | 10775 | if (attr->sample_type & PERF_SAMPLE_REGS_USER) { |
4018994f | 10776 | ret = perf_reg_validate(attr->sample_regs_user); |
c5ebcedb JO |
10777 | if (ret) |
10778 | return ret; | |
10779 | } | |
10780 | ||
10781 | if (attr->sample_type & PERF_SAMPLE_STACK_USER) { | |
10782 | if (!arch_perf_have_user_stack_dump()) | |
10783 | return -ENOSYS; | |
10784 | ||
10785 | /* | |
10786 | * We have __u32 type for the size, but so far | |
10787 | * we can only use __u16 as maximum due to the | |
10788 | * __u16 sample size limit. | |
10789 | */ | |
10790 | if (attr->sample_stack_user >= USHRT_MAX) | |
78b562fb | 10791 | return -EINVAL; |
c5ebcedb | 10792 | else if (!IS_ALIGNED(attr->sample_stack_user, sizeof(u64))) |
78b562fb | 10793 | return -EINVAL; |
c5ebcedb | 10794 | } |
4018994f | 10795 | |
5f970521 JO |
10796 | if (!attr->sample_max_stack) |
10797 | attr->sample_max_stack = sysctl_perf_event_max_stack; | |
10798 | ||
60e2364e SE |
10799 | if (attr->sample_type & PERF_SAMPLE_REGS_INTR) |
10800 | ret = perf_reg_validate(attr->sample_regs_intr); | |
974802ea PZ |
10801 | out: |
10802 | return ret; | |
10803 | ||
10804 | err_size: | |
10805 | put_user(sizeof(*attr), &uattr->size); | |
10806 | ret = -E2BIG; | |
10807 | goto out; | |
10808 | } | |
10809 | ||
ac9721f3 PZ |
10810 | static int |
10811 | perf_event_set_output(struct perf_event *event, struct perf_event *output_event) | |
a4be7c27 | 10812 | { |
b69cf536 | 10813 | struct ring_buffer *rb = NULL; |
a4be7c27 PZ |
10814 | int ret = -EINVAL; |
10815 | ||
ac9721f3 | 10816 | if (!output_event) |
a4be7c27 PZ |
10817 | goto set; |
10818 | ||
ac9721f3 PZ |
10819 | /* don't allow circular references */ |
10820 | if (event == output_event) | |
a4be7c27 PZ |
10821 | goto out; |
10822 | ||
0f139300 PZ |
10823 | /* |
10824 | * Don't allow cross-cpu buffers | |
10825 | */ | |
10826 | if (output_event->cpu != event->cpu) | |
10827 | goto out; | |
10828 | ||
10829 | /* | |
76369139 | 10830 | * If its not a per-cpu rb, it must be the same task. |
0f139300 PZ |
10831 | */ |
10832 | if (output_event->cpu == -1 && output_event->ctx != event->ctx) | |
10833 | goto out; | |
10834 | ||
34f43927 PZ |
10835 | /* |
10836 | * Mixing clocks in the same buffer is trouble you don't need. | |
10837 | */ | |
10838 | if (output_event->clock != event->clock) | |
10839 | goto out; | |
10840 | ||
9ecda41a WN |
10841 | /* |
10842 | * Either writing ring buffer from beginning or from end. | |
10843 | * Mixing is not allowed. | |
10844 | */ | |
10845 | if (is_write_backward(output_event) != is_write_backward(event)) | |
10846 | goto out; | |
10847 | ||
45bfb2e5 PZ |
10848 | /* |
10849 | * If both events generate aux data, they must be on the same PMU | |
10850 | */ | |
10851 | if (has_aux(event) && has_aux(output_event) && | |
10852 | event->pmu != output_event->pmu) | |
10853 | goto out; | |
10854 | ||
a4be7c27 | 10855 | set: |
cdd6c482 | 10856 | mutex_lock(&event->mmap_mutex); |
ac9721f3 PZ |
10857 | /* Can't redirect output if we've got an active mmap() */ |
10858 | if (atomic_read(&event->mmap_count)) | |
10859 | goto unlock; | |
a4be7c27 | 10860 | |
ac9721f3 | 10861 | if (output_event) { |
76369139 FW |
10862 | /* get the rb we want to redirect to */ |
10863 | rb = ring_buffer_get(output_event); | |
10864 | if (!rb) | |
ac9721f3 | 10865 | goto unlock; |
a4be7c27 PZ |
10866 | } |
10867 | ||
b69cf536 | 10868 | ring_buffer_attach(event, rb); |
9bb5d40c | 10869 | |
a4be7c27 | 10870 | ret = 0; |
ac9721f3 PZ |
10871 | unlock: |
10872 | mutex_unlock(&event->mmap_mutex); | |
10873 | ||
a4be7c27 | 10874 | out: |
a4be7c27 PZ |
10875 | return ret; |
10876 | } | |
10877 | ||
f63a8daa PZ |
10878 | static void mutex_lock_double(struct mutex *a, struct mutex *b) |
10879 | { | |
10880 | if (b < a) | |
10881 | swap(a, b); | |
10882 | ||
10883 | mutex_lock(a); | |
10884 | mutex_lock_nested(b, SINGLE_DEPTH_NESTING); | |
10885 | } | |
10886 | ||
34f43927 PZ |
10887 | static int perf_event_set_clock(struct perf_event *event, clockid_t clk_id) |
10888 | { | |
10889 | bool nmi_safe = false; | |
10890 | ||
10891 | switch (clk_id) { | |
10892 | case CLOCK_MONOTONIC: | |
10893 | event->clock = &ktime_get_mono_fast_ns; | |
10894 | nmi_safe = true; | |
10895 | break; | |
10896 | ||
10897 | case CLOCK_MONOTONIC_RAW: | |
10898 | event->clock = &ktime_get_raw_fast_ns; | |
10899 | nmi_safe = true; | |
10900 | break; | |
10901 | ||
10902 | case CLOCK_REALTIME: | |
10903 | event->clock = &ktime_get_real_ns; | |
10904 | break; | |
10905 | ||
10906 | case CLOCK_BOOTTIME: | |
9285ec4c | 10907 | event->clock = &ktime_get_boottime_ns; |
34f43927 PZ |
10908 | break; |
10909 | ||
10910 | case CLOCK_TAI: | |
9285ec4c | 10911 | event->clock = &ktime_get_clocktai_ns; |
34f43927 PZ |
10912 | break; |
10913 | ||
10914 | default: | |
10915 | return -EINVAL; | |
10916 | } | |
10917 | ||
10918 | if (!nmi_safe && !(event->pmu->capabilities & PERF_PMU_CAP_NO_NMI)) | |
10919 | return -EINVAL; | |
10920 | ||
10921 | return 0; | |
10922 | } | |
10923 | ||
321027c1 PZ |
10924 | /* |
10925 | * Variation on perf_event_ctx_lock_nested(), except we take two context | |
10926 | * mutexes. | |
10927 | */ | |
10928 | static struct perf_event_context * | |
10929 | __perf_event_ctx_lock_double(struct perf_event *group_leader, | |
10930 | struct perf_event_context *ctx) | |
10931 | { | |
10932 | struct perf_event_context *gctx; | |
10933 | ||
10934 | again: | |
10935 | rcu_read_lock(); | |
10936 | gctx = READ_ONCE(group_leader->ctx); | |
8c94abbb | 10937 | if (!refcount_inc_not_zero(&gctx->refcount)) { |
321027c1 PZ |
10938 | rcu_read_unlock(); |
10939 | goto again; | |
10940 | } | |
10941 | rcu_read_unlock(); | |
10942 | ||
10943 | mutex_lock_double(&gctx->mutex, &ctx->mutex); | |
10944 | ||
10945 | if (group_leader->ctx != gctx) { | |
10946 | mutex_unlock(&ctx->mutex); | |
10947 | mutex_unlock(&gctx->mutex); | |
10948 | put_ctx(gctx); | |
10949 | goto again; | |
10950 | } | |
10951 | ||
10952 | return gctx; | |
10953 | } | |
10954 | ||
0793a61d | 10955 | /** |
cdd6c482 | 10956 | * sys_perf_event_open - open a performance event, associate it to a task/cpu |
9f66a381 | 10957 | * |
cdd6c482 | 10958 | * @attr_uptr: event_id type attributes for monitoring/sampling |
0793a61d | 10959 | * @pid: target pid |
9f66a381 | 10960 | * @cpu: target cpu |
cdd6c482 | 10961 | * @group_fd: group leader event fd |
0793a61d | 10962 | */ |
cdd6c482 IM |
10963 | SYSCALL_DEFINE5(perf_event_open, |
10964 | struct perf_event_attr __user *, attr_uptr, | |
2743a5b0 | 10965 | pid_t, pid, int, cpu, int, group_fd, unsigned long, flags) |
0793a61d | 10966 | { |
b04243ef PZ |
10967 | struct perf_event *group_leader = NULL, *output_event = NULL; |
10968 | struct perf_event *event, *sibling; | |
cdd6c482 | 10969 | struct perf_event_attr attr; |
f63a8daa | 10970 | struct perf_event_context *ctx, *uninitialized_var(gctx); |
cdd6c482 | 10971 | struct file *event_file = NULL; |
2903ff01 | 10972 | struct fd group = {NULL, 0}; |
38a81da2 | 10973 | struct task_struct *task = NULL; |
89a1e187 | 10974 | struct pmu *pmu; |
ea635c64 | 10975 | int event_fd; |
b04243ef | 10976 | int move_group = 0; |
dc86cabe | 10977 | int err; |
a21b0b35 | 10978 | int f_flags = O_RDWR; |
79dff51e | 10979 | int cgroup_fd = -1; |
0793a61d | 10980 | |
2743a5b0 | 10981 | /* for future expandability... */ |
e5d1367f | 10982 | if (flags & ~PERF_FLAG_ALL) |
2743a5b0 PM |
10983 | return -EINVAL; |
10984 | ||
da97e184 JFG |
10985 | /* Do we allow access to perf_event_open(2) ? */ |
10986 | err = security_perf_event_open(&attr, PERF_SECURITY_OPEN); | |
10987 | if (err) | |
10988 | return err; | |
10989 | ||
dc86cabe IM |
10990 | err = perf_copy_attr(attr_uptr, &attr); |
10991 | if (err) | |
10992 | return err; | |
eab656ae | 10993 | |
0764771d | 10994 | if (!attr.exclude_kernel) { |
da97e184 JFG |
10995 | err = perf_allow_kernel(&attr); |
10996 | if (err) | |
10997 | return err; | |
0764771d PZ |
10998 | } |
10999 | ||
e4222673 HB |
11000 | if (attr.namespaces) { |
11001 | if (!capable(CAP_SYS_ADMIN)) | |
11002 | return -EACCES; | |
11003 | } | |
11004 | ||
df58ab24 | 11005 | if (attr.freq) { |
cdd6c482 | 11006 | if (attr.sample_freq > sysctl_perf_event_sample_rate) |
df58ab24 | 11007 | return -EINVAL; |
0819b2e3 PZ |
11008 | } else { |
11009 | if (attr.sample_period & (1ULL << 63)) | |
11010 | return -EINVAL; | |
df58ab24 PZ |
11011 | } |
11012 | ||
fc7ce9c7 | 11013 | /* Only privileged users can get physical addresses */ |
da97e184 JFG |
11014 | if ((attr.sample_type & PERF_SAMPLE_PHYS_ADDR)) { |
11015 | err = perf_allow_kernel(&attr); | |
11016 | if (err) | |
11017 | return err; | |
11018 | } | |
fc7ce9c7 | 11019 | |
b0c8fdc7 DH |
11020 | err = security_locked_down(LOCKDOWN_PERF); |
11021 | if (err && (attr.sample_type & PERF_SAMPLE_REGS_INTR)) | |
11022 | /* REGS_INTR can leak data, lockdown must prevent this */ | |
11023 | return err; | |
11024 | ||
11025 | err = 0; | |
11026 | ||
e5d1367f SE |
11027 | /* |
11028 | * In cgroup mode, the pid argument is used to pass the fd | |
11029 | * opened to the cgroup directory in cgroupfs. The cpu argument | |
11030 | * designates the cpu on which to monitor threads from that | |
11031 | * cgroup. | |
11032 | */ | |
11033 | if ((flags & PERF_FLAG_PID_CGROUP) && (pid == -1 || cpu == -1)) | |
11034 | return -EINVAL; | |
11035 | ||
a21b0b35 YD |
11036 | if (flags & PERF_FLAG_FD_CLOEXEC) |
11037 | f_flags |= O_CLOEXEC; | |
11038 | ||
11039 | event_fd = get_unused_fd_flags(f_flags); | |
ea635c64 AV |
11040 | if (event_fd < 0) |
11041 | return event_fd; | |
11042 | ||
ac9721f3 | 11043 | if (group_fd != -1) { |
2903ff01 AV |
11044 | err = perf_fget_light(group_fd, &group); |
11045 | if (err) | |
d14b12d7 | 11046 | goto err_fd; |
2903ff01 | 11047 | group_leader = group.file->private_data; |
ac9721f3 PZ |
11048 | if (flags & PERF_FLAG_FD_OUTPUT) |
11049 | output_event = group_leader; | |
11050 | if (flags & PERF_FLAG_FD_NO_GROUP) | |
11051 | group_leader = NULL; | |
11052 | } | |
11053 | ||
e5d1367f | 11054 | if (pid != -1 && !(flags & PERF_FLAG_PID_CGROUP)) { |
c6be5a5c PZ |
11055 | task = find_lively_task_by_vpid(pid); |
11056 | if (IS_ERR(task)) { | |
11057 | err = PTR_ERR(task); | |
11058 | goto err_group_fd; | |
11059 | } | |
11060 | } | |
11061 | ||
1f4ee503 PZ |
11062 | if (task && group_leader && |
11063 | group_leader->attr.inherit != attr.inherit) { | |
11064 | err = -EINVAL; | |
11065 | goto err_task; | |
11066 | } | |
11067 | ||
79c9ce57 PZ |
11068 | if (task) { |
11069 | err = mutex_lock_interruptible(&task->signal->cred_guard_mutex); | |
11070 | if (err) | |
e5aeee51 | 11071 | goto err_task; |
79c9ce57 PZ |
11072 | |
11073 | /* | |
11074 | * Reuse ptrace permission checks for now. | |
11075 | * | |
11076 | * We must hold cred_guard_mutex across this and any potential | |
11077 | * perf_install_in_context() call for this new event to | |
11078 | * serialize against exec() altering our credentials (and the | |
11079 | * perf_event_exit_task() that could imply). | |
11080 | */ | |
11081 | err = -EACCES; | |
11082 | if (!ptrace_may_access(task, PTRACE_MODE_READ_REALCREDS)) | |
11083 | goto err_cred; | |
11084 | } | |
11085 | ||
79dff51e MF |
11086 | if (flags & PERF_FLAG_PID_CGROUP) |
11087 | cgroup_fd = pid; | |
11088 | ||
4dc0da86 | 11089 | event = perf_event_alloc(&attr, cpu, task, group_leader, NULL, |
79dff51e | 11090 | NULL, NULL, cgroup_fd); |
d14b12d7 SE |
11091 | if (IS_ERR(event)) { |
11092 | err = PTR_ERR(event); | |
79c9ce57 | 11093 | goto err_cred; |
d14b12d7 SE |
11094 | } |
11095 | ||
53b25335 VW |
11096 | if (is_sampling_event(event)) { |
11097 | if (event->pmu->capabilities & PERF_PMU_CAP_NO_INTERRUPT) { | |
a1396555 | 11098 | err = -EOPNOTSUPP; |
53b25335 VW |
11099 | goto err_alloc; |
11100 | } | |
11101 | } | |
11102 | ||
89a1e187 PZ |
11103 | /* |
11104 | * Special case software events and allow them to be part of | |
11105 | * any hardware group. | |
11106 | */ | |
11107 | pmu = event->pmu; | |
b04243ef | 11108 | |
34f43927 PZ |
11109 | if (attr.use_clockid) { |
11110 | err = perf_event_set_clock(event, attr.clockid); | |
11111 | if (err) | |
11112 | goto err_alloc; | |
11113 | } | |
11114 | ||
4ff6a8de DCC |
11115 | if (pmu->task_ctx_nr == perf_sw_context) |
11116 | event->event_caps |= PERF_EV_CAP_SOFTWARE; | |
11117 | ||
a1150c20 SL |
11118 | if (group_leader) { |
11119 | if (is_software_event(event) && | |
11120 | !in_software_context(group_leader)) { | |
b04243ef | 11121 | /* |
a1150c20 SL |
11122 | * If the event is a sw event, but the group_leader |
11123 | * is on hw context. | |
b04243ef | 11124 | * |
a1150c20 SL |
11125 | * Allow the addition of software events to hw |
11126 | * groups, this is safe because software events | |
11127 | * never fail to schedule. | |
b04243ef | 11128 | */ |
a1150c20 SL |
11129 | pmu = group_leader->ctx->pmu; |
11130 | } else if (!is_software_event(event) && | |
11131 | is_software_event(group_leader) && | |
4ff6a8de | 11132 | (group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { |
b04243ef PZ |
11133 | /* |
11134 | * In case the group is a pure software group, and we | |
11135 | * try to add a hardware event, move the whole group to | |
11136 | * the hardware context. | |
11137 | */ | |
11138 | move_group = 1; | |
11139 | } | |
11140 | } | |
89a1e187 PZ |
11141 | |
11142 | /* | |
11143 | * Get the target context (task or percpu): | |
11144 | */ | |
4af57ef2 | 11145 | ctx = find_get_context(pmu, task, event); |
89a1e187 PZ |
11146 | if (IS_ERR(ctx)) { |
11147 | err = PTR_ERR(ctx); | |
c6be5a5c | 11148 | goto err_alloc; |
89a1e187 PZ |
11149 | } |
11150 | ||
ccff286d | 11151 | /* |
cdd6c482 | 11152 | * Look up the group leader (we will attach this event to it): |
04289bb9 | 11153 | */ |
ac9721f3 | 11154 | if (group_leader) { |
dc86cabe | 11155 | err = -EINVAL; |
04289bb9 | 11156 | |
04289bb9 | 11157 | /* |
ccff286d IM |
11158 | * Do not allow a recursive hierarchy (this new sibling |
11159 | * becoming part of another group-sibling): | |
11160 | */ | |
11161 | if (group_leader->group_leader != group_leader) | |
c3f00c70 | 11162 | goto err_context; |
34f43927 PZ |
11163 | |
11164 | /* All events in a group should have the same clock */ | |
11165 | if (group_leader->clock != event->clock) | |
11166 | goto err_context; | |
11167 | ||
ccff286d | 11168 | /* |
64aee2a9 MR |
11169 | * Make sure we're both events for the same CPU; |
11170 | * grouping events for different CPUs is broken; since | |
11171 | * you can never concurrently schedule them anyhow. | |
04289bb9 | 11172 | */ |
64aee2a9 MR |
11173 | if (group_leader->cpu != event->cpu) |
11174 | goto err_context; | |
c3c87e77 | 11175 | |
64aee2a9 MR |
11176 | /* |
11177 | * Make sure we're both on the same task, or both | |
11178 | * per-CPU events. | |
11179 | */ | |
11180 | if (group_leader->ctx->task != ctx->task) | |
11181 | goto err_context; | |
11182 | ||
11183 | /* | |
11184 | * Do not allow to attach to a group in a different task | |
11185 | * or CPU context. If we're moving SW events, we'll fix | |
11186 | * this up later, so allow that. | |
11187 | */ | |
11188 | if (!move_group && group_leader->ctx != ctx) | |
11189 | goto err_context; | |
b04243ef | 11190 | |
3b6f9e5c PM |
11191 | /* |
11192 | * Only a group leader can be exclusive or pinned | |
11193 | */ | |
0d48696f | 11194 | if (attr.exclusive || attr.pinned) |
c3f00c70 | 11195 | goto err_context; |
ac9721f3 PZ |
11196 | } |
11197 | ||
11198 | if (output_event) { | |
11199 | err = perf_event_set_output(event, output_event); | |
11200 | if (err) | |
c3f00c70 | 11201 | goto err_context; |
ac9721f3 | 11202 | } |
0793a61d | 11203 | |
a21b0b35 YD |
11204 | event_file = anon_inode_getfile("[perf_event]", &perf_fops, event, |
11205 | f_flags); | |
ea635c64 AV |
11206 | if (IS_ERR(event_file)) { |
11207 | err = PTR_ERR(event_file); | |
201c2f85 | 11208 | event_file = NULL; |
c3f00c70 | 11209 | goto err_context; |
ea635c64 | 11210 | } |
9b51f66d | 11211 | |
b04243ef | 11212 | if (move_group) { |
321027c1 PZ |
11213 | gctx = __perf_event_ctx_lock_double(group_leader, ctx); |
11214 | ||
84c4e620 PZ |
11215 | if (gctx->task == TASK_TOMBSTONE) { |
11216 | err = -ESRCH; | |
11217 | goto err_locked; | |
11218 | } | |
321027c1 PZ |
11219 | |
11220 | /* | |
11221 | * Check if we raced against another sys_perf_event_open() call | |
11222 | * moving the software group underneath us. | |
11223 | */ | |
11224 | if (!(group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { | |
11225 | /* | |
11226 | * If someone moved the group out from under us, check | |
11227 | * if this new event wound up on the same ctx, if so | |
11228 | * its the regular !move_group case, otherwise fail. | |
11229 | */ | |
11230 | if (gctx != ctx) { | |
11231 | err = -EINVAL; | |
11232 | goto err_locked; | |
11233 | } else { | |
11234 | perf_event_ctx_unlock(group_leader, gctx); | |
11235 | move_group = 0; | |
11236 | } | |
11237 | } | |
8a58ddae AS |
11238 | |
11239 | /* | |
11240 | * Failure to create exclusive events returns -EBUSY. | |
11241 | */ | |
11242 | err = -EBUSY; | |
11243 | if (!exclusive_event_installable(group_leader, ctx)) | |
11244 | goto err_locked; | |
11245 | ||
11246 | for_each_sibling_event(sibling, group_leader) { | |
11247 | if (!exclusive_event_installable(sibling, ctx)) | |
11248 | goto err_locked; | |
11249 | } | |
f55fc2a5 PZ |
11250 | } else { |
11251 | mutex_lock(&ctx->mutex); | |
11252 | } | |
11253 | ||
84c4e620 PZ |
11254 | if (ctx->task == TASK_TOMBSTONE) { |
11255 | err = -ESRCH; | |
11256 | goto err_locked; | |
11257 | } | |
11258 | ||
a723968c PZ |
11259 | if (!perf_event_validate_size(event)) { |
11260 | err = -E2BIG; | |
11261 | goto err_locked; | |
11262 | } | |
11263 | ||
a63fbed7 TG |
11264 | if (!task) { |
11265 | /* | |
11266 | * Check if the @cpu we're creating an event for is online. | |
11267 | * | |
11268 | * We use the perf_cpu_context::ctx::mutex to serialize against | |
11269 | * the hotplug notifiers. See perf_event_{init,exit}_cpu(). | |
11270 | */ | |
11271 | struct perf_cpu_context *cpuctx = | |
11272 | container_of(ctx, struct perf_cpu_context, ctx); | |
11273 | ||
11274 | if (!cpuctx->online) { | |
11275 | err = -ENODEV; | |
11276 | goto err_locked; | |
11277 | } | |
11278 | } | |
11279 | ||
ab43762e AS |
11280 | if (event->attr.aux_output && !perf_get_aux_event(event, group_leader)) |
11281 | goto err_locked; | |
a63fbed7 | 11282 | |
f55fc2a5 PZ |
11283 | /* |
11284 | * Must be under the same ctx::mutex as perf_install_in_context(), | |
11285 | * because we need to serialize with concurrent event creation. | |
11286 | */ | |
11287 | if (!exclusive_event_installable(event, ctx)) { | |
f55fc2a5 PZ |
11288 | err = -EBUSY; |
11289 | goto err_locked; | |
11290 | } | |
f63a8daa | 11291 | |
f55fc2a5 PZ |
11292 | WARN_ON_ONCE(ctx->parent_ctx); |
11293 | ||
79c9ce57 PZ |
11294 | /* |
11295 | * This is the point on no return; we cannot fail hereafter. This is | |
11296 | * where we start modifying current state. | |
11297 | */ | |
11298 | ||
f55fc2a5 | 11299 | if (move_group) { |
f63a8daa PZ |
11300 | /* |
11301 | * See perf_event_ctx_lock() for comments on the details | |
11302 | * of swizzling perf_event::ctx. | |
11303 | */ | |
45a0e07a | 11304 | perf_remove_from_context(group_leader, 0); |
279b5165 | 11305 | put_ctx(gctx); |
0231bb53 | 11306 | |
edb39592 | 11307 | for_each_sibling_event(sibling, group_leader) { |
45a0e07a | 11308 | perf_remove_from_context(sibling, 0); |
b04243ef PZ |
11309 | put_ctx(gctx); |
11310 | } | |
b04243ef | 11311 | |
f63a8daa PZ |
11312 | /* |
11313 | * Wait for everybody to stop referencing the events through | |
11314 | * the old lists, before installing it on new lists. | |
11315 | */ | |
0cda4c02 | 11316 | synchronize_rcu(); |
f63a8daa | 11317 | |
8f95b435 PZI |
11318 | /* |
11319 | * Install the group siblings before the group leader. | |
11320 | * | |
11321 | * Because a group leader will try and install the entire group | |
11322 | * (through the sibling list, which is still in-tact), we can | |
11323 | * end up with siblings installed in the wrong context. | |
11324 | * | |
11325 | * By installing siblings first we NO-OP because they're not | |
11326 | * reachable through the group lists. | |
11327 | */ | |
edb39592 | 11328 | for_each_sibling_event(sibling, group_leader) { |
8f95b435 | 11329 | perf_event__state_init(sibling); |
9fc81d87 | 11330 | perf_install_in_context(ctx, sibling, sibling->cpu); |
b04243ef PZ |
11331 | get_ctx(ctx); |
11332 | } | |
8f95b435 PZI |
11333 | |
11334 | /* | |
11335 | * Removing from the context ends up with disabled | |
11336 | * event. What we want here is event in the initial | |
11337 | * startup state, ready to be add into new context. | |
11338 | */ | |
11339 | perf_event__state_init(group_leader); | |
11340 | perf_install_in_context(ctx, group_leader, group_leader->cpu); | |
11341 | get_ctx(ctx); | |
bed5b25a AS |
11342 | } |
11343 | ||
f73e22ab PZ |
11344 | /* |
11345 | * Precalculate sample_data sizes; do while holding ctx::mutex such | |
11346 | * that we're serialized against further additions and before | |
11347 | * perf_install_in_context() which is the point the event is active and | |
11348 | * can use these values. | |
11349 | */ | |
11350 | perf_event__header_size(event); | |
11351 | perf_event__id_header_size(event); | |
11352 | ||
78cd2c74 PZ |
11353 | event->owner = current; |
11354 | ||
e2d37cd2 | 11355 | perf_install_in_context(ctx, event, event->cpu); |
fe4b04fa | 11356 | perf_unpin_context(ctx); |
f63a8daa | 11357 | |
f55fc2a5 | 11358 | if (move_group) |
321027c1 | 11359 | perf_event_ctx_unlock(group_leader, gctx); |
d859e29f | 11360 | mutex_unlock(&ctx->mutex); |
9b51f66d | 11361 | |
79c9ce57 PZ |
11362 | if (task) { |
11363 | mutex_unlock(&task->signal->cred_guard_mutex); | |
11364 | put_task_struct(task); | |
11365 | } | |
11366 | ||
cdd6c482 IM |
11367 | mutex_lock(¤t->perf_event_mutex); |
11368 | list_add_tail(&event->owner_entry, ¤t->perf_event_list); | |
11369 | mutex_unlock(¤t->perf_event_mutex); | |
082ff5a2 | 11370 | |
8a49542c PZ |
11371 | /* |
11372 | * Drop the reference on the group_event after placing the | |
11373 | * new event on the sibling_list. This ensures destruction | |
11374 | * of the group leader will find the pointer to itself in | |
11375 | * perf_group_detach(). | |
11376 | */ | |
2903ff01 | 11377 | fdput(group); |
ea635c64 AV |
11378 | fd_install(event_fd, event_file); |
11379 | return event_fd; | |
0793a61d | 11380 | |
f55fc2a5 PZ |
11381 | err_locked: |
11382 | if (move_group) | |
321027c1 | 11383 | perf_event_ctx_unlock(group_leader, gctx); |
f55fc2a5 PZ |
11384 | mutex_unlock(&ctx->mutex); |
11385 | /* err_file: */ | |
11386 | fput(event_file); | |
c3f00c70 | 11387 | err_context: |
fe4b04fa | 11388 | perf_unpin_context(ctx); |
ea635c64 | 11389 | put_ctx(ctx); |
c6be5a5c | 11390 | err_alloc: |
13005627 PZ |
11391 | /* |
11392 | * If event_file is set, the fput() above will have called ->release() | |
11393 | * and that will take care of freeing the event. | |
11394 | */ | |
11395 | if (!event_file) | |
11396 | free_event(event); | |
79c9ce57 PZ |
11397 | err_cred: |
11398 | if (task) | |
11399 | mutex_unlock(&task->signal->cred_guard_mutex); | |
1f4ee503 | 11400 | err_task: |
e7d0bc04 PZ |
11401 | if (task) |
11402 | put_task_struct(task); | |
89a1e187 | 11403 | err_group_fd: |
2903ff01 | 11404 | fdput(group); |
ea635c64 AV |
11405 | err_fd: |
11406 | put_unused_fd(event_fd); | |
dc86cabe | 11407 | return err; |
0793a61d TG |
11408 | } |
11409 | ||
fb0459d7 AV |
11410 | /** |
11411 | * perf_event_create_kernel_counter | |
11412 | * | |
11413 | * @attr: attributes of the counter to create | |
11414 | * @cpu: cpu in which the counter is bound | |
38a81da2 | 11415 | * @task: task to profile (NULL for percpu) |
fb0459d7 AV |
11416 | */ |
11417 | struct perf_event * | |
11418 | perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, | |
38a81da2 | 11419 | struct task_struct *task, |
4dc0da86 AK |
11420 | perf_overflow_handler_t overflow_handler, |
11421 | void *context) | |
fb0459d7 | 11422 | { |
fb0459d7 | 11423 | struct perf_event_context *ctx; |
c3f00c70 | 11424 | struct perf_event *event; |
fb0459d7 | 11425 | int err; |
d859e29f | 11426 | |
fb0459d7 | 11427 | /* |
dce5affb AS |
11428 | * Grouping is not supported for kernel events, neither is 'AUX', |
11429 | * make sure the caller's intentions are adjusted. | |
fb0459d7 | 11430 | */ |
dce5affb AS |
11431 | if (attr->aux_output) |
11432 | return ERR_PTR(-EINVAL); | |
d859e29f | 11433 | |
4dc0da86 | 11434 | event = perf_event_alloc(attr, cpu, task, NULL, NULL, |
79dff51e | 11435 | overflow_handler, context, -1); |
c3f00c70 PZ |
11436 | if (IS_ERR(event)) { |
11437 | err = PTR_ERR(event); | |
11438 | goto err; | |
11439 | } | |
d859e29f | 11440 | |
f8697762 | 11441 | /* Mark owner so we could distinguish it from user events. */ |
63b6da39 | 11442 | event->owner = TASK_TOMBSTONE; |
f8697762 | 11443 | |
f25d8ba9 AS |
11444 | /* |
11445 | * Get the target context (task or percpu): | |
11446 | */ | |
4af57ef2 | 11447 | ctx = find_get_context(event->pmu, task, event); |
c6567f64 FW |
11448 | if (IS_ERR(ctx)) { |
11449 | err = PTR_ERR(ctx); | |
c3f00c70 | 11450 | goto err_free; |
d859e29f | 11451 | } |
fb0459d7 | 11452 | |
fb0459d7 AV |
11453 | WARN_ON_ONCE(ctx->parent_ctx); |
11454 | mutex_lock(&ctx->mutex); | |
84c4e620 PZ |
11455 | if (ctx->task == TASK_TOMBSTONE) { |
11456 | err = -ESRCH; | |
11457 | goto err_unlock; | |
11458 | } | |
11459 | ||
a63fbed7 TG |
11460 | if (!task) { |
11461 | /* | |
11462 | * Check if the @cpu we're creating an event for is online. | |
11463 | * | |
11464 | * We use the perf_cpu_context::ctx::mutex to serialize against | |
11465 | * the hotplug notifiers. See perf_event_{init,exit}_cpu(). | |
11466 | */ | |
11467 | struct perf_cpu_context *cpuctx = | |
11468 | container_of(ctx, struct perf_cpu_context, ctx); | |
11469 | if (!cpuctx->online) { | |
11470 | err = -ENODEV; | |
11471 | goto err_unlock; | |
11472 | } | |
11473 | } | |
11474 | ||
bed5b25a | 11475 | if (!exclusive_event_installable(event, ctx)) { |
bed5b25a | 11476 | err = -EBUSY; |
84c4e620 | 11477 | goto err_unlock; |
bed5b25a AS |
11478 | } |
11479 | ||
4ce54af8 | 11480 | perf_install_in_context(ctx, event, event->cpu); |
fe4b04fa | 11481 | perf_unpin_context(ctx); |
fb0459d7 AV |
11482 | mutex_unlock(&ctx->mutex); |
11483 | ||
fb0459d7 AV |
11484 | return event; |
11485 | ||
84c4e620 PZ |
11486 | err_unlock: |
11487 | mutex_unlock(&ctx->mutex); | |
11488 | perf_unpin_context(ctx); | |
11489 | put_ctx(ctx); | |
c3f00c70 PZ |
11490 | err_free: |
11491 | free_event(event); | |
11492 | err: | |
c6567f64 | 11493 | return ERR_PTR(err); |
9b51f66d | 11494 | } |
fb0459d7 | 11495 | EXPORT_SYMBOL_GPL(perf_event_create_kernel_counter); |
9b51f66d | 11496 | |
0cda4c02 YZ |
11497 | void perf_pmu_migrate_context(struct pmu *pmu, int src_cpu, int dst_cpu) |
11498 | { | |
11499 | struct perf_event_context *src_ctx; | |
11500 | struct perf_event_context *dst_ctx; | |
11501 | struct perf_event *event, *tmp; | |
11502 | LIST_HEAD(events); | |
11503 | ||
11504 | src_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, src_cpu)->ctx; | |
11505 | dst_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, dst_cpu)->ctx; | |
11506 | ||
f63a8daa PZ |
11507 | /* |
11508 | * See perf_event_ctx_lock() for comments on the details | |
11509 | * of swizzling perf_event::ctx. | |
11510 | */ | |
11511 | mutex_lock_double(&src_ctx->mutex, &dst_ctx->mutex); | |
0cda4c02 YZ |
11512 | list_for_each_entry_safe(event, tmp, &src_ctx->event_list, |
11513 | event_entry) { | |
45a0e07a | 11514 | perf_remove_from_context(event, 0); |
9a545de0 | 11515 | unaccount_event_cpu(event, src_cpu); |
0cda4c02 | 11516 | put_ctx(src_ctx); |
9886167d | 11517 | list_add(&event->migrate_entry, &events); |
0cda4c02 | 11518 | } |
0cda4c02 | 11519 | |
8f95b435 PZI |
11520 | /* |
11521 | * Wait for the events to quiesce before re-instating them. | |
11522 | */ | |
0cda4c02 YZ |
11523 | synchronize_rcu(); |
11524 | ||
8f95b435 PZI |
11525 | /* |
11526 | * Re-instate events in 2 passes. | |
11527 | * | |
11528 | * Skip over group leaders and only install siblings on this first | |
11529 | * pass, siblings will not get enabled without a leader, however a | |
11530 | * leader will enable its siblings, even if those are still on the old | |
11531 | * context. | |
11532 | */ | |
11533 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { | |
11534 | if (event->group_leader == event) | |
11535 | continue; | |
11536 | ||
11537 | list_del(&event->migrate_entry); | |
11538 | if (event->state >= PERF_EVENT_STATE_OFF) | |
11539 | event->state = PERF_EVENT_STATE_INACTIVE; | |
11540 | account_event_cpu(event, dst_cpu); | |
11541 | perf_install_in_context(dst_ctx, event, dst_cpu); | |
11542 | get_ctx(dst_ctx); | |
11543 | } | |
11544 | ||
11545 | /* | |
11546 | * Once all the siblings are setup properly, install the group leaders | |
11547 | * to make it go. | |
11548 | */ | |
9886167d PZ |
11549 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { |
11550 | list_del(&event->migrate_entry); | |
0cda4c02 YZ |
11551 | if (event->state >= PERF_EVENT_STATE_OFF) |
11552 | event->state = PERF_EVENT_STATE_INACTIVE; | |
9a545de0 | 11553 | account_event_cpu(event, dst_cpu); |
0cda4c02 YZ |
11554 | perf_install_in_context(dst_ctx, event, dst_cpu); |
11555 | get_ctx(dst_ctx); | |
11556 | } | |
11557 | mutex_unlock(&dst_ctx->mutex); | |
f63a8daa | 11558 | mutex_unlock(&src_ctx->mutex); |
0cda4c02 YZ |
11559 | } |
11560 | EXPORT_SYMBOL_GPL(perf_pmu_migrate_context); | |
11561 | ||
cdd6c482 | 11562 | static void sync_child_event(struct perf_event *child_event, |
38b200d6 | 11563 | struct task_struct *child) |
d859e29f | 11564 | { |
cdd6c482 | 11565 | struct perf_event *parent_event = child_event->parent; |
8bc20959 | 11566 | u64 child_val; |
d859e29f | 11567 | |
cdd6c482 IM |
11568 | if (child_event->attr.inherit_stat) |
11569 | perf_event_read_event(child_event, child); | |
38b200d6 | 11570 | |
b5e58793 | 11571 | child_val = perf_event_count(child_event); |
d859e29f PM |
11572 | |
11573 | /* | |
11574 | * Add back the child's count to the parent's count: | |
11575 | */ | |
a6e6dea6 | 11576 | atomic64_add(child_val, &parent_event->child_count); |
cdd6c482 IM |
11577 | atomic64_add(child_event->total_time_enabled, |
11578 | &parent_event->child_total_time_enabled); | |
11579 | atomic64_add(child_event->total_time_running, | |
11580 | &parent_event->child_total_time_running); | |
d859e29f PM |
11581 | } |
11582 | ||
9b51f66d | 11583 | static void |
8ba289b8 PZ |
11584 | perf_event_exit_event(struct perf_event *child_event, |
11585 | struct perf_event_context *child_ctx, | |
11586 | struct task_struct *child) | |
9b51f66d | 11587 | { |
8ba289b8 PZ |
11588 | struct perf_event *parent_event = child_event->parent; |
11589 | ||
1903d50c PZ |
11590 | /* |
11591 | * Do not destroy the 'original' grouping; because of the context | |
11592 | * switch optimization the original events could've ended up in a | |
11593 | * random child task. | |
11594 | * | |
11595 | * If we were to destroy the original group, all group related | |
11596 | * operations would cease to function properly after this random | |
11597 | * child dies. | |
11598 | * | |
11599 | * Do destroy all inherited groups, we don't care about those | |
11600 | * and being thorough is better. | |
11601 | */ | |
32132a3d PZ |
11602 | raw_spin_lock_irq(&child_ctx->lock); |
11603 | WARN_ON_ONCE(child_ctx->is_active); | |
11604 | ||
8ba289b8 | 11605 | if (parent_event) |
32132a3d PZ |
11606 | perf_group_detach(child_event); |
11607 | list_del_event(child_event, child_ctx); | |
0d3d73aa | 11608 | perf_event_set_state(child_event, PERF_EVENT_STATE_EXIT); /* is_event_hup() */ |
32132a3d | 11609 | raw_spin_unlock_irq(&child_ctx->lock); |
0cc0c027 | 11610 | |
9b51f66d | 11611 | /* |
8ba289b8 | 11612 | * Parent events are governed by their filedesc, retain them. |
9b51f66d | 11613 | */ |
8ba289b8 | 11614 | if (!parent_event) { |
179033b3 | 11615 | perf_event_wakeup(child_event); |
8ba289b8 | 11616 | return; |
4bcf349a | 11617 | } |
8ba289b8 PZ |
11618 | /* |
11619 | * Child events can be cleaned up. | |
11620 | */ | |
11621 | ||
11622 | sync_child_event(child_event, child); | |
11623 | ||
11624 | /* | |
11625 | * Remove this event from the parent's list | |
11626 | */ | |
11627 | WARN_ON_ONCE(parent_event->ctx->parent_ctx); | |
11628 | mutex_lock(&parent_event->child_mutex); | |
11629 | list_del_init(&child_event->child_list); | |
11630 | mutex_unlock(&parent_event->child_mutex); | |
11631 | ||
11632 | /* | |
11633 | * Kick perf_poll() for is_event_hup(). | |
11634 | */ | |
11635 | perf_event_wakeup(parent_event); | |
11636 | free_event(child_event); | |
11637 | put_event(parent_event); | |
9b51f66d IM |
11638 | } |
11639 | ||
8dc85d54 | 11640 | static void perf_event_exit_task_context(struct task_struct *child, int ctxn) |
9b51f66d | 11641 | { |
211de6eb | 11642 | struct perf_event_context *child_ctx, *clone_ctx = NULL; |
63b6da39 | 11643 | struct perf_event *child_event, *next; |
63b6da39 PZ |
11644 | |
11645 | WARN_ON_ONCE(child != current); | |
9b51f66d | 11646 | |
6a3351b6 | 11647 | child_ctx = perf_pin_task_context(child, ctxn); |
63b6da39 | 11648 | if (!child_ctx) |
9b51f66d IM |
11649 | return; |
11650 | ||
ad3a37de | 11651 | /* |
6a3351b6 PZ |
11652 | * In order to reduce the amount of tricky in ctx tear-down, we hold |
11653 | * ctx::mutex over the entire thing. This serializes against almost | |
11654 | * everything that wants to access the ctx. | |
11655 | * | |
11656 | * The exception is sys_perf_event_open() / | |
11657 | * perf_event_create_kernel_count() which does find_get_context() | |
11658 | * without ctx::mutex (it cannot because of the move_group double mutex | |
11659 | * lock thing). See the comments in perf_install_in_context(). | |
ad3a37de | 11660 | */ |
6a3351b6 | 11661 | mutex_lock(&child_ctx->mutex); |
c93f7669 PM |
11662 | |
11663 | /* | |
6a3351b6 PZ |
11664 | * In a single ctx::lock section, de-schedule the events and detach the |
11665 | * context from the task such that we cannot ever get it scheduled back | |
11666 | * in. | |
c93f7669 | 11667 | */ |
6a3351b6 | 11668 | raw_spin_lock_irq(&child_ctx->lock); |
487f05e1 | 11669 | task_ctx_sched_out(__get_cpu_context(child_ctx), child_ctx, EVENT_ALL); |
4a1c0f26 | 11670 | |
71a851b4 | 11671 | /* |
63b6da39 PZ |
11672 | * Now that the context is inactive, destroy the task <-> ctx relation |
11673 | * and mark the context dead. | |
71a851b4 | 11674 | */ |
63b6da39 PZ |
11675 | RCU_INIT_POINTER(child->perf_event_ctxp[ctxn], NULL); |
11676 | put_ctx(child_ctx); /* cannot be last */ | |
11677 | WRITE_ONCE(child_ctx->task, TASK_TOMBSTONE); | |
11678 | put_task_struct(current); /* cannot be last */ | |
4a1c0f26 | 11679 | |
211de6eb | 11680 | clone_ctx = unclone_ctx(child_ctx); |
6a3351b6 | 11681 | raw_spin_unlock_irq(&child_ctx->lock); |
9f498cc5 | 11682 | |
211de6eb PZ |
11683 | if (clone_ctx) |
11684 | put_ctx(clone_ctx); | |
4a1c0f26 | 11685 | |
9f498cc5 | 11686 | /* |
cdd6c482 IM |
11687 | * Report the task dead after unscheduling the events so that we |
11688 | * won't get any samples after PERF_RECORD_EXIT. We can however still | |
11689 | * get a few PERF_RECORD_READ events. | |
9f498cc5 | 11690 | */ |
cdd6c482 | 11691 | perf_event_task(child, child_ctx, 0); |
a63eaf34 | 11692 | |
ebf905fc | 11693 | list_for_each_entry_safe(child_event, next, &child_ctx->event_list, event_entry) |
8ba289b8 | 11694 | perf_event_exit_event(child_event, child_ctx, child); |
8bc20959 | 11695 | |
a63eaf34 PM |
11696 | mutex_unlock(&child_ctx->mutex); |
11697 | ||
11698 | put_ctx(child_ctx); | |
9b51f66d IM |
11699 | } |
11700 | ||
8dc85d54 PZ |
11701 | /* |
11702 | * When a child task exits, feed back event values to parent events. | |
79c9ce57 PZ |
11703 | * |
11704 | * Can be called with cred_guard_mutex held when called from | |
11705 | * install_exec_creds(). | |
8dc85d54 PZ |
11706 | */ |
11707 | void perf_event_exit_task(struct task_struct *child) | |
11708 | { | |
8882135b | 11709 | struct perf_event *event, *tmp; |
8dc85d54 PZ |
11710 | int ctxn; |
11711 | ||
8882135b PZ |
11712 | mutex_lock(&child->perf_event_mutex); |
11713 | list_for_each_entry_safe(event, tmp, &child->perf_event_list, | |
11714 | owner_entry) { | |
11715 | list_del_init(&event->owner_entry); | |
11716 | ||
11717 | /* | |
11718 | * Ensure the list deletion is visible before we clear | |
11719 | * the owner, closes a race against perf_release() where | |
11720 | * we need to serialize on the owner->perf_event_mutex. | |
11721 | */ | |
f47c02c0 | 11722 | smp_store_release(&event->owner, NULL); |
8882135b PZ |
11723 | } |
11724 | mutex_unlock(&child->perf_event_mutex); | |
11725 | ||
8dc85d54 PZ |
11726 | for_each_task_context_nr(ctxn) |
11727 | perf_event_exit_task_context(child, ctxn); | |
4e93ad60 JO |
11728 | |
11729 | /* | |
11730 | * The perf_event_exit_task_context calls perf_event_task | |
11731 | * with child's task_ctx, which generates EXIT events for | |
11732 | * child contexts and sets child->perf_event_ctxp[] to NULL. | |
11733 | * At this point we need to send EXIT events to cpu contexts. | |
11734 | */ | |
11735 | perf_event_task(child, NULL, 0); | |
8dc85d54 PZ |
11736 | } |
11737 | ||
889ff015 FW |
11738 | static void perf_free_event(struct perf_event *event, |
11739 | struct perf_event_context *ctx) | |
11740 | { | |
11741 | struct perf_event *parent = event->parent; | |
11742 | ||
11743 | if (WARN_ON_ONCE(!parent)) | |
11744 | return; | |
11745 | ||
11746 | mutex_lock(&parent->child_mutex); | |
11747 | list_del_init(&event->child_list); | |
11748 | mutex_unlock(&parent->child_mutex); | |
11749 | ||
a6fa941d | 11750 | put_event(parent); |
889ff015 | 11751 | |
652884fe | 11752 | raw_spin_lock_irq(&ctx->lock); |
8a49542c | 11753 | perf_group_detach(event); |
889ff015 | 11754 | list_del_event(event, ctx); |
652884fe | 11755 | raw_spin_unlock_irq(&ctx->lock); |
889ff015 FW |
11756 | free_event(event); |
11757 | } | |
11758 | ||
bbbee908 | 11759 | /* |
1cf8dfe8 PZ |
11760 | * Free a context as created by inheritance by perf_event_init_task() below, |
11761 | * used by fork() in case of fail. | |
652884fe | 11762 | * |
1cf8dfe8 PZ |
11763 | * Even though the task has never lived, the context and events have been |
11764 | * exposed through the child_list, so we must take care tearing it all down. | |
bbbee908 | 11765 | */ |
cdd6c482 | 11766 | void perf_event_free_task(struct task_struct *task) |
bbbee908 | 11767 | { |
8dc85d54 | 11768 | struct perf_event_context *ctx; |
cdd6c482 | 11769 | struct perf_event *event, *tmp; |
8dc85d54 | 11770 | int ctxn; |
bbbee908 | 11771 | |
8dc85d54 PZ |
11772 | for_each_task_context_nr(ctxn) { |
11773 | ctx = task->perf_event_ctxp[ctxn]; | |
11774 | if (!ctx) | |
11775 | continue; | |
bbbee908 | 11776 | |
8dc85d54 | 11777 | mutex_lock(&ctx->mutex); |
e552a838 PZ |
11778 | raw_spin_lock_irq(&ctx->lock); |
11779 | /* | |
11780 | * Destroy the task <-> ctx relation and mark the context dead. | |
11781 | * | |
11782 | * This is important because even though the task hasn't been | |
11783 | * exposed yet the context has been (through child_list). | |
11784 | */ | |
11785 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], NULL); | |
11786 | WRITE_ONCE(ctx->task, TASK_TOMBSTONE); | |
11787 | put_task_struct(task); /* cannot be last */ | |
11788 | raw_spin_unlock_irq(&ctx->lock); | |
bbbee908 | 11789 | |
15121c78 | 11790 | list_for_each_entry_safe(event, tmp, &ctx->event_list, event_entry) |
8dc85d54 | 11791 | perf_free_event(event, ctx); |
bbbee908 | 11792 | |
8dc85d54 | 11793 | mutex_unlock(&ctx->mutex); |
1cf8dfe8 PZ |
11794 | |
11795 | /* | |
11796 | * perf_event_release_kernel() could've stolen some of our | |
11797 | * child events and still have them on its free_list. In that | |
11798 | * case we must wait for these events to have been freed (in | |
11799 | * particular all their references to this task must've been | |
11800 | * dropped). | |
11801 | * | |
11802 | * Without this copy_process() will unconditionally free this | |
11803 | * task (irrespective of its reference count) and | |
11804 | * _free_event()'s put_task_struct(event->hw.target) will be a | |
11805 | * use-after-free. | |
11806 | * | |
11807 | * Wait for all events to drop their context reference. | |
11808 | */ | |
11809 | wait_var_event(&ctx->refcount, refcount_read(&ctx->refcount) == 1); | |
11810 | put_ctx(ctx); /* must be last */ | |
8dc85d54 | 11811 | } |
889ff015 FW |
11812 | } |
11813 | ||
4e231c79 PZ |
11814 | void perf_event_delayed_put(struct task_struct *task) |
11815 | { | |
11816 | int ctxn; | |
11817 | ||
11818 | for_each_task_context_nr(ctxn) | |
11819 | WARN_ON_ONCE(task->perf_event_ctxp[ctxn]); | |
11820 | } | |
11821 | ||
e03e7ee3 | 11822 | struct file *perf_event_get(unsigned int fd) |
ffe8690c | 11823 | { |
02e5ad97 | 11824 | struct file *file = fget(fd); |
e03e7ee3 AS |
11825 | if (!file) |
11826 | return ERR_PTR(-EBADF); | |
ffe8690c | 11827 | |
e03e7ee3 AS |
11828 | if (file->f_op != &perf_fops) { |
11829 | fput(file); | |
11830 | return ERR_PTR(-EBADF); | |
11831 | } | |
ffe8690c | 11832 | |
e03e7ee3 | 11833 | return file; |
ffe8690c KX |
11834 | } |
11835 | ||
f8d959a5 YS |
11836 | const struct perf_event *perf_get_event(struct file *file) |
11837 | { | |
11838 | if (file->f_op != &perf_fops) | |
11839 | return ERR_PTR(-EINVAL); | |
11840 | ||
11841 | return file->private_data; | |
11842 | } | |
11843 | ||
ffe8690c KX |
11844 | const struct perf_event_attr *perf_event_attrs(struct perf_event *event) |
11845 | { | |
11846 | if (!event) | |
11847 | return ERR_PTR(-EINVAL); | |
11848 | ||
11849 | return &event->attr; | |
11850 | } | |
11851 | ||
97dee4f3 | 11852 | /* |
788faab7 | 11853 | * Inherit an event from parent task to child task. |
d8a8cfc7 PZ |
11854 | * |
11855 | * Returns: | |
11856 | * - valid pointer on success | |
11857 | * - NULL for orphaned events | |
11858 | * - IS_ERR() on error | |
97dee4f3 PZ |
11859 | */ |
11860 | static struct perf_event * | |
11861 | inherit_event(struct perf_event *parent_event, | |
11862 | struct task_struct *parent, | |
11863 | struct perf_event_context *parent_ctx, | |
11864 | struct task_struct *child, | |
11865 | struct perf_event *group_leader, | |
11866 | struct perf_event_context *child_ctx) | |
11867 | { | |
8ca2bd41 | 11868 | enum perf_event_state parent_state = parent_event->state; |
97dee4f3 | 11869 | struct perf_event *child_event; |
cee010ec | 11870 | unsigned long flags; |
97dee4f3 PZ |
11871 | |
11872 | /* | |
11873 | * Instead of creating recursive hierarchies of events, | |
11874 | * we link inherited events back to the original parent, | |
11875 | * which has a filp for sure, which we use as the reference | |
11876 | * count: | |
11877 | */ | |
11878 | if (parent_event->parent) | |
11879 | parent_event = parent_event->parent; | |
11880 | ||
11881 | child_event = perf_event_alloc(&parent_event->attr, | |
11882 | parent_event->cpu, | |
d580ff86 | 11883 | child, |
97dee4f3 | 11884 | group_leader, parent_event, |
79dff51e | 11885 | NULL, NULL, -1); |
97dee4f3 PZ |
11886 | if (IS_ERR(child_event)) |
11887 | return child_event; | |
a6fa941d | 11888 | |
313ccb96 JO |
11889 | |
11890 | if ((child_event->attach_state & PERF_ATTACH_TASK_DATA) && | |
11891 | !child_ctx->task_ctx_data) { | |
11892 | struct pmu *pmu = child_event->pmu; | |
11893 | ||
11894 | child_ctx->task_ctx_data = kzalloc(pmu->task_ctx_size, | |
11895 | GFP_KERNEL); | |
11896 | if (!child_ctx->task_ctx_data) { | |
11897 | free_event(child_event); | |
697d8778 | 11898 | return ERR_PTR(-ENOMEM); |
313ccb96 JO |
11899 | } |
11900 | } | |
11901 | ||
c6e5b732 PZ |
11902 | /* |
11903 | * is_orphaned_event() and list_add_tail(&parent_event->child_list) | |
11904 | * must be under the same lock in order to serialize against | |
11905 | * perf_event_release_kernel(), such that either we must observe | |
11906 | * is_orphaned_event() or they will observe us on the child_list. | |
11907 | */ | |
11908 | mutex_lock(&parent_event->child_mutex); | |
fadfe7be JO |
11909 | if (is_orphaned_event(parent_event) || |
11910 | !atomic_long_inc_not_zero(&parent_event->refcount)) { | |
c6e5b732 | 11911 | mutex_unlock(&parent_event->child_mutex); |
313ccb96 | 11912 | /* task_ctx_data is freed with child_ctx */ |
a6fa941d AV |
11913 | free_event(child_event); |
11914 | return NULL; | |
11915 | } | |
11916 | ||
97dee4f3 PZ |
11917 | get_ctx(child_ctx); |
11918 | ||
11919 | /* | |
11920 | * Make the child state follow the state of the parent event, | |
11921 | * not its attr.disabled bit. We hold the parent's mutex, | |
11922 | * so we won't race with perf_event_{en, dis}able_family. | |
11923 | */ | |
1929def9 | 11924 | if (parent_state >= PERF_EVENT_STATE_INACTIVE) |
97dee4f3 PZ |
11925 | child_event->state = PERF_EVENT_STATE_INACTIVE; |
11926 | else | |
11927 | child_event->state = PERF_EVENT_STATE_OFF; | |
11928 | ||
11929 | if (parent_event->attr.freq) { | |
11930 | u64 sample_period = parent_event->hw.sample_period; | |
11931 | struct hw_perf_event *hwc = &child_event->hw; | |
11932 | ||
11933 | hwc->sample_period = sample_period; | |
11934 | hwc->last_period = sample_period; | |
11935 | ||
11936 | local64_set(&hwc->period_left, sample_period); | |
11937 | } | |
11938 | ||
11939 | child_event->ctx = child_ctx; | |
11940 | child_event->overflow_handler = parent_event->overflow_handler; | |
4dc0da86 AK |
11941 | child_event->overflow_handler_context |
11942 | = parent_event->overflow_handler_context; | |
97dee4f3 | 11943 | |
614b6780 TG |
11944 | /* |
11945 | * Precalculate sample_data sizes | |
11946 | */ | |
11947 | perf_event__header_size(child_event); | |
6844c09d | 11948 | perf_event__id_header_size(child_event); |
614b6780 | 11949 | |
97dee4f3 PZ |
11950 | /* |
11951 | * Link it up in the child's context: | |
11952 | */ | |
cee010ec | 11953 | raw_spin_lock_irqsave(&child_ctx->lock, flags); |
97dee4f3 | 11954 | add_event_to_ctx(child_event, child_ctx); |
cee010ec | 11955 | raw_spin_unlock_irqrestore(&child_ctx->lock, flags); |
97dee4f3 | 11956 | |
97dee4f3 PZ |
11957 | /* |
11958 | * Link this into the parent event's child list | |
11959 | */ | |
97dee4f3 PZ |
11960 | list_add_tail(&child_event->child_list, &parent_event->child_list); |
11961 | mutex_unlock(&parent_event->child_mutex); | |
11962 | ||
11963 | return child_event; | |
11964 | } | |
11965 | ||
d8a8cfc7 PZ |
11966 | /* |
11967 | * Inherits an event group. | |
11968 | * | |
11969 | * This will quietly suppress orphaned events; !inherit_event() is not an error. | |
11970 | * This matches with perf_event_release_kernel() removing all child events. | |
11971 | * | |
11972 | * Returns: | |
11973 | * - 0 on success | |
11974 | * - <0 on error | |
11975 | */ | |
97dee4f3 PZ |
11976 | static int inherit_group(struct perf_event *parent_event, |
11977 | struct task_struct *parent, | |
11978 | struct perf_event_context *parent_ctx, | |
11979 | struct task_struct *child, | |
11980 | struct perf_event_context *child_ctx) | |
11981 | { | |
11982 | struct perf_event *leader; | |
11983 | struct perf_event *sub; | |
11984 | struct perf_event *child_ctr; | |
11985 | ||
11986 | leader = inherit_event(parent_event, parent, parent_ctx, | |
11987 | child, NULL, child_ctx); | |
11988 | if (IS_ERR(leader)) | |
11989 | return PTR_ERR(leader); | |
d8a8cfc7 PZ |
11990 | /* |
11991 | * @leader can be NULL here because of is_orphaned_event(). In this | |
11992 | * case inherit_event() will create individual events, similar to what | |
11993 | * perf_group_detach() would do anyway. | |
11994 | */ | |
edb39592 | 11995 | for_each_sibling_event(sub, parent_event) { |
97dee4f3 PZ |
11996 | child_ctr = inherit_event(sub, parent, parent_ctx, |
11997 | child, leader, child_ctx); | |
11998 | if (IS_ERR(child_ctr)) | |
11999 | return PTR_ERR(child_ctr); | |
f733c6b5 | 12000 | |
00496fe5 | 12001 | if (sub->aux_event == parent_event && child_ctr && |
f733c6b5 AS |
12002 | !perf_get_aux_event(child_ctr, leader)) |
12003 | return -EINVAL; | |
97dee4f3 PZ |
12004 | } |
12005 | return 0; | |
889ff015 FW |
12006 | } |
12007 | ||
d8a8cfc7 PZ |
12008 | /* |
12009 | * Creates the child task context and tries to inherit the event-group. | |
12010 | * | |
12011 | * Clears @inherited_all on !attr.inherited or error. Note that we'll leave | |
12012 | * inherited_all set when we 'fail' to inherit an orphaned event; this is | |
12013 | * consistent with perf_event_release_kernel() removing all child events. | |
12014 | * | |
12015 | * Returns: | |
12016 | * - 0 on success | |
12017 | * - <0 on error | |
12018 | */ | |
889ff015 FW |
12019 | static int |
12020 | inherit_task_group(struct perf_event *event, struct task_struct *parent, | |
12021 | struct perf_event_context *parent_ctx, | |
8dc85d54 | 12022 | struct task_struct *child, int ctxn, |
889ff015 FW |
12023 | int *inherited_all) |
12024 | { | |
12025 | int ret; | |
8dc85d54 | 12026 | struct perf_event_context *child_ctx; |
889ff015 FW |
12027 | |
12028 | if (!event->attr.inherit) { | |
12029 | *inherited_all = 0; | |
12030 | return 0; | |
bbbee908 PZ |
12031 | } |
12032 | ||
fe4b04fa | 12033 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 FW |
12034 | if (!child_ctx) { |
12035 | /* | |
12036 | * This is executed from the parent task context, so | |
12037 | * inherit events that have been marked for cloning. | |
12038 | * First allocate and initialize a context for the | |
12039 | * child. | |
12040 | */ | |
734df5ab | 12041 | child_ctx = alloc_perf_context(parent_ctx->pmu, child); |
889ff015 FW |
12042 | if (!child_ctx) |
12043 | return -ENOMEM; | |
bbbee908 | 12044 | |
8dc85d54 | 12045 | child->perf_event_ctxp[ctxn] = child_ctx; |
889ff015 FW |
12046 | } |
12047 | ||
12048 | ret = inherit_group(event, parent, parent_ctx, | |
12049 | child, child_ctx); | |
12050 | ||
12051 | if (ret) | |
12052 | *inherited_all = 0; | |
12053 | ||
12054 | return ret; | |
bbbee908 PZ |
12055 | } |
12056 | ||
9b51f66d | 12057 | /* |
cdd6c482 | 12058 | * Initialize the perf_event context in task_struct |
9b51f66d | 12059 | */ |
985c8dcb | 12060 | static int perf_event_init_context(struct task_struct *child, int ctxn) |
9b51f66d | 12061 | { |
889ff015 | 12062 | struct perf_event_context *child_ctx, *parent_ctx; |
cdd6c482 IM |
12063 | struct perf_event_context *cloned_ctx; |
12064 | struct perf_event *event; | |
9b51f66d | 12065 | struct task_struct *parent = current; |
564c2b21 | 12066 | int inherited_all = 1; |
dddd3379 | 12067 | unsigned long flags; |
6ab423e0 | 12068 | int ret = 0; |
9b51f66d | 12069 | |
8dc85d54 | 12070 | if (likely(!parent->perf_event_ctxp[ctxn])) |
6ab423e0 PZ |
12071 | return 0; |
12072 | ||
ad3a37de | 12073 | /* |
25346b93 PM |
12074 | * If the parent's context is a clone, pin it so it won't get |
12075 | * swapped under us. | |
ad3a37de | 12076 | */ |
8dc85d54 | 12077 | parent_ctx = perf_pin_task_context(parent, ctxn); |
ffb4ef21 PZ |
12078 | if (!parent_ctx) |
12079 | return 0; | |
25346b93 | 12080 | |
ad3a37de PM |
12081 | /* |
12082 | * No need to check if parent_ctx != NULL here; since we saw | |
12083 | * it non-NULL earlier, the only reason for it to become NULL | |
12084 | * is if we exit, and since we're currently in the middle of | |
12085 | * a fork we can't be exiting at the same time. | |
12086 | */ | |
ad3a37de | 12087 | |
9b51f66d IM |
12088 | /* |
12089 | * Lock the parent list. No need to lock the child - not PID | |
12090 | * hashed yet and not running, so nobody can access it. | |
12091 | */ | |
d859e29f | 12092 | mutex_lock(&parent_ctx->mutex); |
9b51f66d IM |
12093 | |
12094 | /* | |
12095 | * We dont have to disable NMIs - we are only looking at | |
12096 | * the list, not manipulating it: | |
12097 | */ | |
6e6804d2 | 12098 | perf_event_groups_for_each(event, &parent_ctx->pinned_groups) { |
8dc85d54 PZ |
12099 | ret = inherit_task_group(event, parent, parent_ctx, |
12100 | child, ctxn, &inherited_all); | |
889ff015 | 12101 | if (ret) |
e7cc4865 | 12102 | goto out_unlock; |
889ff015 | 12103 | } |
b93f7978 | 12104 | |
dddd3379 TG |
12105 | /* |
12106 | * We can't hold ctx->lock when iterating the ->flexible_group list due | |
12107 | * to allocations, but we need to prevent rotation because | |
12108 | * rotate_ctx() will change the list from interrupt context. | |
12109 | */ | |
12110 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); | |
12111 | parent_ctx->rotate_disable = 1; | |
12112 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); | |
12113 | ||
6e6804d2 | 12114 | perf_event_groups_for_each(event, &parent_ctx->flexible_groups) { |
8dc85d54 PZ |
12115 | ret = inherit_task_group(event, parent, parent_ctx, |
12116 | child, ctxn, &inherited_all); | |
889ff015 | 12117 | if (ret) |
e7cc4865 | 12118 | goto out_unlock; |
564c2b21 PM |
12119 | } |
12120 | ||
dddd3379 TG |
12121 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); |
12122 | parent_ctx->rotate_disable = 0; | |
dddd3379 | 12123 | |
8dc85d54 | 12124 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 | 12125 | |
05cbaa28 | 12126 | if (child_ctx && inherited_all) { |
564c2b21 PM |
12127 | /* |
12128 | * Mark the child context as a clone of the parent | |
12129 | * context, or of whatever the parent is a clone of. | |
c5ed5145 PZ |
12130 | * |
12131 | * Note that if the parent is a clone, the holding of | |
12132 | * parent_ctx->lock avoids it from being uncloned. | |
564c2b21 | 12133 | */ |
c5ed5145 | 12134 | cloned_ctx = parent_ctx->parent_ctx; |
ad3a37de PM |
12135 | if (cloned_ctx) { |
12136 | child_ctx->parent_ctx = cloned_ctx; | |
25346b93 | 12137 | child_ctx->parent_gen = parent_ctx->parent_gen; |
564c2b21 PM |
12138 | } else { |
12139 | child_ctx->parent_ctx = parent_ctx; | |
12140 | child_ctx->parent_gen = parent_ctx->generation; | |
12141 | } | |
12142 | get_ctx(child_ctx->parent_ctx); | |
9b51f66d IM |
12143 | } |
12144 | ||
c5ed5145 | 12145 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); |
e7cc4865 | 12146 | out_unlock: |
d859e29f | 12147 | mutex_unlock(&parent_ctx->mutex); |
6ab423e0 | 12148 | |
25346b93 | 12149 | perf_unpin_context(parent_ctx); |
fe4b04fa | 12150 | put_ctx(parent_ctx); |
ad3a37de | 12151 | |
6ab423e0 | 12152 | return ret; |
9b51f66d IM |
12153 | } |
12154 | ||
8dc85d54 PZ |
12155 | /* |
12156 | * Initialize the perf_event context in task_struct | |
12157 | */ | |
12158 | int perf_event_init_task(struct task_struct *child) | |
12159 | { | |
12160 | int ctxn, ret; | |
12161 | ||
8550d7cb ON |
12162 | memset(child->perf_event_ctxp, 0, sizeof(child->perf_event_ctxp)); |
12163 | mutex_init(&child->perf_event_mutex); | |
12164 | INIT_LIST_HEAD(&child->perf_event_list); | |
12165 | ||
8dc85d54 PZ |
12166 | for_each_task_context_nr(ctxn) { |
12167 | ret = perf_event_init_context(child, ctxn); | |
6c72e350 PZ |
12168 | if (ret) { |
12169 | perf_event_free_task(child); | |
8dc85d54 | 12170 | return ret; |
6c72e350 | 12171 | } |
8dc85d54 PZ |
12172 | } |
12173 | ||
12174 | return 0; | |
12175 | } | |
12176 | ||
220b140b PM |
12177 | static void __init perf_event_init_all_cpus(void) |
12178 | { | |
b28ab83c | 12179 | struct swevent_htable *swhash; |
220b140b | 12180 | int cpu; |
220b140b | 12181 | |
a63fbed7 TG |
12182 | zalloc_cpumask_var(&perf_online_mask, GFP_KERNEL); |
12183 | ||
220b140b | 12184 | for_each_possible_cpu(cpu) { |
b28ab83c PZ |
12185 | swhash = &per_cpu(swevent_htable, cpu); |
12186 | mutex_init(&swhash->hlist_mutex); | |
2fde4f94 | 12187 | INIT_LIST_HEAD(&per_cpu(active_ctx_list, cpu)); |
f2fb6bef KL |
12188 | |
12189 | INIT_LIST_HEAD(&per_cpu(pmu_sb_events.list, cpu)); | |
12190 | raw_spin_lock_init(&per_cpu(pmu_sb_events.lock, cpu)); | |
e48c1788 | 12191 | |
058fe1c0 DCC |
12192 | #ifdef CONFIG_CGROUP_PERF |
12193 | INIT_LIST_HEAD(&per_cpu(cgrp_cpuctx_list, cpu)); | |
12194 | #endif | |
e48c1788 | 12195 | INIT_LIST_HEAD(&per_cpu(sched_cb_list, cpu)); |
220b140b PM |
12196 | } |
12197 | } | |
12198 | ||
d18bf422 | 12199 | static void perf_swevent_init_cpu(unsigned int cpu) |
0793a61d | 12200 | { |
108b02cf | 12201 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
0793a61d | 12202 | |
b28ab83c | 12203 | mutex_lock(&swhash->hlist_mutex); |
059fcd8c | 12204 | if (swhash->hlist_refcount > 0 && !swevent_hlist_deref(swhash)) { |
76e1d904 FW |
12205 | struct swevent_hlist *hlist; |
12206 | ||
b28ab83c PZ |
12207 | hlist = kzalloc_node(sizeof(*hlist), GFP_KERNEL, cpu_to_node(cpu)); |
12208 | WARN_ON(!hlist); | |
12209 | rcu_assign_pointer(swhash->swevent_hlist, hlist); | |
76e1d904 | 12210 | } |
b28ab83c | 12211 | mutex_unlock(&swhash->hlist_mutex); |
0793a61d TG |
12212 | } |
12213 | ||
2965faa5 | 12214 | #if defined CONFIG_HOTPLUG_CPU || defined CONFIG_KEXEC_CORE |
108b02cf | 12215 | static void __perf_event_exit_context(void *__info) |
0793a61d | 12216 | { |
108b02cf | 12217 | struct perf_event_context *ctx = __info; |
fae3fde6 PZ |
12218 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
12219 | struct perf_event *event; | |
0793a61d | 12220 | |
fae3fde6 | 12221 | raw_spin_lock(&ctx->lock); |
0ee098c9 | 12222 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
fae3fde6 | 12223 | list_for_each_entry(event, &ctx->event_list, event_entry) |
45a0e07a | 12224 | __perf_remove_from_context(event, cpuctx, ctx, (void *)DETACH_GROUP); |
fae3fde6 | 12225 | raw_spin_unlock(&ctx->lock); |
0793a61d | 12226 | } |
108b02cf PZ |
12227 | |
12228 | static void perf_event_exit_cpu_context(int cpu) | |
12229 | { | |
a63fbed7 | 12230 | struct perf_cpu_context *cpuctx; |
108b02cf PZ |
12231 | struct perf_event_context *ctx; |
12232 | struct pmu *pmu; | |
108b02cf | 12233 | |
a63fbed7 TG |
12234 | mutex_lock(&pmus_lock); |
12235 | list_for_each_entry(pmu, &pmus, entry) { | |
12236 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
12237 | ctx = &cpuctx->ctx; | |
108b02cf PZ |
12238 | |
12239 | mutex_lock(&ctx->mutex); | |
12240 | smp_call_function_single(cpu, __perf_event_exit_context, ctx, 1); | |
a63fbed7 | 12241 | cpuctx->online = 0; |
108b02cf PZ |
12242 | mutex_unlock(&ctx->mutex); |
12243 | } | |
a63fbed7 TG |
12244 | cpumask_clear_cpu(cpu, perf_online_mask); |
12245 | mutex_unlock(&pmus_lock); | |
108b02cf | 12246 | } |
00e16c3d TG |
12247 | #else |
12248 | ||
12249 | static void perf_event_exit_cpu_context(int cpu) { } | |
12250 | ||
12251 | #endif | |
108b02cf | 12252 | |
a63fbed7 TG |
12253 | int perf_event_init_cpu(unsigned int cpu) |
12254 | { | |
12255 | struct perf_cpu_context *cpuctx; | |
12256 | struct perf_event_context *ctx; | |
12257 | struct pmu *pmu; | |
12258 | ||
12259 | perf_swevent_init_cpu(cpu); | |
12260 | ||
12261 | mutex_lock(&pmus_lock); | |
12262 | cpumask_set_cpu(cpu, perf_online_mask); | |
12263 | list_for_each_entry(pmu, &pmus, entry) { | |
12264 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
12265 | ctx = &cpuctx->ctx; | |
12266 | ||
12267 | mutex_lock(&ctx->mutex); | |
12268 | cpuctx->online = 1; | |
12269 | mutex_unlock(&ctx->mutex); | |
12270 | } | |
12271 | mutex_unlock(&pmus_lock); | |
12272 | ||
12273 | return 0; | |
12274 | } | |
12275 | ||
00e16c3d | 12276 | int perf_event_exit_cpu(unsigned int cpu) |
0793a61d | 12277 | { |
e3703f8c | 12278 | perf_event_exit_cpu_context(cpu); |
00e16c3d | 12279 | return 0; |
0793a61d | 12280 | } |
0793a61d | 12281 | |
c277443c PZ |
12282 | static int |
12283 | perf_reboot(struct notifier_block *notifier, unsigned long val, void *v) | |
12284 | { | |
12285 | int cpu; | |
12286 | ||
12287 | for_each_online_cpu(cpu) | |
12288 | perf_event_exit_cpu(cpu); | |
12289 | ||
12290 | return NOTIFY_OK; | |
12291 | } | |
12292 | ||
12293 | /* | |
12294 | * Run the perf reboot notifier at the very last possible moment so that | |
12295 | * the generic watchdog code runs as long as possible. | |
12296 | */ | |
12297 | static struct notifier_block perf_reboot_notifier = { | |
12298 | .notifier_call = perf_reboot, | |
12299 | .priority = INT_MIN, | |
12300 | }; | |
12301 | ||
cdd6c482 | 12302 | void __init perf_event_init(void) |
0793a61d | 12303 | { |
3c502e7a JW |
12304 | int ret; |
12305 | ||
2e80a82a PZ |
12306 | idr_init(&pmu_idr); |
12307 | ||
220b140b | 12308 | perf_event_init_all_cpus(); |
b0a873eb | 12309 | init_srcu_struct(&pmus_srcu); |
2e80a82a PZ |
12310 | perf_pmu_register(&perf_swevent, "software", PERF_TYPE_SOFTWARE); |
12311 | perf_pmu_register(&perf_cpu_clock, NULL, -1); | |
12312 | perf_pmu_register(&perf_task_clock, NULL, -1); | |
b0a873eb | 12313 | perf_tp_register(); |
00e16c3d | 12314 | perf_event_init_cpu(smp_processor_id()); |
c277443c | 12315 | register_reboot_notifier(&perf_reboot_notifier); |
3c502e7a JW |
12316 | |
12317 | ret = init_hw_breakpoint(); | |
12318 | WARN(ret, "hw_breakpoint initialization failed with: %d", ret); | |
b2029520 | 12319 | |
b01c3a00 JO |
12320 | /* |
12321 | * Build time assertion that we keep the data_head at the intended | |
12322 | * location. IOW, validation we got the __reserved[] size right. | |
12323 | */ | |
12324 | BUILD_BUG_ON((offsetof(struct perf_event_mmap_page, data_head)) | |
12325 | != 1024); | |
0793a61d | 12326 | } |
abe43400 | 12327 | |
fd979c01 CS |
12328 | ssize_t perf_event_sysfs_show(struct device *dev, struct device_attribute *attr, |
12329 | char *page) | |
12330 | { | |
12331 | struct perf_pmu_events_attr *pmu_attr = | |
12332 | container_of(attr, struct perf_pmu_events_attr, attr); | |
12333 | ||
12334 | if (pmu_attr->event_str) | |
12335 | return sprintf(page, "%s\n", pmu_attr->event_str); | |
12336 | ||
12337 | return 0; | |
12338 | } | |
675965b0 | 12339 | EXPORT_SYMBOL_GPL(perf_event_sysfs_show); |
fd979c01 | 12340 | |
abe43400 PZ |
12341 | static int __init perf_event_sysfs_init(void) |
12342 | { | |
12343 | struct pmu *pmu; | |
12344 | int ret; | |
12345 | ||
12346 | mutex_lock(&pmus_lock); | |
12347 | ||
12348 | ret = bus_register(&pmu_bus); | |
12349 | if (ret) | |
12350 | goto unlock; | |
12351 | ||
12352 | list_for_each_entry(pmu, &pmus, entry) { | |
12353 | if (!pmu->name || pmu->type < 0) | |
12354 | continue; | |
12355 | ||
12356 | ret = pmu_dev_alloc(pmu); | |
12357 | WARN(ret, "Failed to register pmu: %s, reason %d\n", pmu->name, ret); | |
12358 | } | |
12359 | pmu_bus_running = 1; | |
12360 | ret = 0; | |
12361 | ||
12362 | unlock: | |
12363 | mutex_unlock(&pmus_lock); | |
12364 | ||
12365 | return ret; | |
12366 | } | |
12367 | device_initcall(perf_event_sysfs_init); | |
e5d1367f SE |
12368 | |
12369 | #ifdef CONFIG_CGROUP_PERF | |
eb95419b TH |
12370 | static struct cgroup_subsys_state * |
12371 | perf_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) | |
e5d1367f SE |
12372 | { |
12373 | struct perf_cgroup *jc; | |
e5d1367f | 12374 | |
1b15d055 | 12375 | jc = kzalloc(sizeof(*jc), GFP_KERNEL); |
e5d1367f SE |
12376 | if (!jc) |
12377 | return ERR_PTR(-ENOMEM); | |
12378 | ||
e5d1367f SE |
12379 | jc->info = alloc_percpu(struct perf_cgroup_info); |
12380 | if (!jc->info) { | |
12381 | kfree(jc); | |
12382 | return ERR_PTR(-ENOMEM); | |
12383 | } | |
12384 | ||
e5d1367f SE |
12385 | return &jc->css; |
12386 | } | |
12387 | ||
eb95419b | 12388 | static void perf_cgroup_css_free(struct cgroup_subsys_state *css) |
e5d1367f | 12389 | { |
eb95419b TH |
12390 | struct perf_cgroup *jc = container_of(css, struct perf_cgroup, css); |
12391 | ||
e5d1367f SE |
12392 | free_percpu(jc->info); |
12393 | kfree(jc); | |
12394 | } | |
12395 | ||
12396 | static int __perf_cgroup_move(void *info) | |
12397 | { | |
12398 | struct task_struct *task = info; | |
ddaaf4e2 | 12399 | rcu_read_lock(); |
e5d1367f | 12400 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT | PERF_CGROUP_SWIN); |
ddaaf4e2 | 12401 | rcu_read_unlock(); |
e5d1367f SE |
12402 | return 0; |
12403 | } | |
12404 | ||
1f7dd3e5 | 12405 | static void perf_cgroup_attach(struct cgroup_taskset *tset) |
e5d1367f | 12406 | { |
bb9d97b6 | 12407 | struct task_struct *task; |
1f7dd3e5 | 12408 | struct cgroup_subsys_state *css; |
bb9d97b6 | 12409 | |
1f7dd3e5 | 12410 | cgroup_taskset_for_each(task, css, tset) |
bb9d97b6 | 12411 | task_function_call(task, __perf_cgroup_move, task); |
e5d1367f SE |
12412 | } |
12413 | ||
073219e9 | 12414 | struct cgroup_subsys perf_event_cgrp_subsys = { |
92fb9748 TH |
12415 | .css_alloc = perf_cgroup_css_alloc, |
12416 | .css_free = perf_cgroup_css_free, | |
bb9d97b6 | 12417 | .attach = perf_cgroup_attach, |
968ebff1 TH |
12418 | /* |
12419 | * Implicitly enable on dfl hierarchy so that perf events can | |
12420 | * always be filtered by cgroup2 path as long as perf_event | |
12421 | * controller is not mounted on a legacy hierarchy. | |
12422 | */ | |
12423 | .implicit_on_dfl = true, | |
8cfd8147 | 12424 | .threaded = true, |
e5d1367f SE |
12425 | }; |
12426 | #endif /* CONFIG_CGROUP_PERF */ |