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 | ||
a096309b PZ |
2669 | if (!task) { |
2670 | cpu_function_call(cpu, __perf_install_in_context, event); | |
2671 | return; | |
2672 | } | |
2673 | ||
2674 | /* | |
2675 | * Should not happen, we validate the ctx is still alive before calling. | |
2676 | */ | |
2677 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) | |
2678 | return; | |
2679 | ||
39a43640 PZ |
2680 | /* |
2681 | * Installing events is tricky because we cannot rely on ctx->is_active | |
2682 | * to be set in case this is the nr_events 0 -> 1 transition. | |
63cae12b PZ |
2683 | * |
2684 | * Instead we use task_curr(), which tells us if the task is running. | |
2685 | * However, since we use task_curr() outside of rq::lock, we can race | |
2686 | * against the actual state. This means the result can be wrong. | |
2687 | * | |
2688 | * If we get a false positive, we retry, this is harmless. | |
2689 | * | |
2690 | * If we get a false negative, things are complicated. If we are after | |
2691 | * perf_event_context_sched_in() ctx::lock will serialize us, and the | |
2692 | * value must be correct. If we're before, it doesn't matter since | |
2693 | * perf_event_context_sched_in() will program the counter. | |
2694 | * | |
2695 | * However, this hinges on the remote context switch having observed | |
2696 | * our task->perf_event_ctxp[] store, such that it will in fact take | |
2697 | * ctx::lock in perf_event_context_sched_in(). | |
2698 | * | |
2699 | * We do this by task_function_call(), if the IPI fails to hit the task | |
2700 | * we know any future context switch of task must see the | |
2701 | * perf_event_ctpx[] store. | |
39a43640 | 2702 | */ |
63cae12b | 2703 | |
63b6da39 | 2704 | /* |
63cae12b PZ |
2705 | * This smp_mb() orders the task->perf_event_ctxp[] store with the |
2706 | * task_cpu() load, such that if the IPI then does not find the task | |
2707 | * running, a future context switch of that task must observe the | |
2708 | * store. | |
63b6da39 | 2709 | */ |
63cae12b PZ |
2710 | smp_mb(); |
2711 | again: | |
2712 | if (!task_function_call(task, __perf_install_in_context, event)) | |
a096309b PZ |
2713 | return; |
2714 | ||
2715 | raw_spin_lock_irq(&ctx->lock); | |
2716 | task = ctx->task; | |
84c4e620 | 2717 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) { |
a096309b PZ |
2718 | /* |
2719 | * Cannot happen because we already checked above (which also | |
2720 | * cannot happen), and we hold ctx->mutex, which serializes us | |
2721 | * against perf_event_exit_task_context(). | |
2722 | */ | |
63b6da39 PZ |
2723 | raw_spin_unlock_irq(&ctx->lock); |
2724 | return; | |
2725 | } | |
39a43640 | 2726 | /* |
63cae12b PZ |
2727 | * If the task is not running, ctx->lock will avoid it becoming so, |
2728 | * thus we can safely install the event. | |
39a43640 | 2729 | */ |
63cae12b PZ |
2730 | if (task_curr(task)) { |
2731 | raw_spin_unlock_irq(&ctx->lock); | |
2732 | goto again; | |
2733 | } | |
2734 | add_event_to_ctx(event, ctx); | |
2735 | raw_spin_unlock_irq(&ctx->lock); | |
0793a61d TG |
2736 | } |
2737 | ||
d859e29f | 2738 | /* |
cdd6c482 | 2739 | * Cross CPU call to enable a performance event |
d859e29f | 2740 | */ |
fae3fde6 PZ |
2741 | static void __perf_event_enable(struct perf_event *event, |
2742 | struct perf_cpu_context *cpuctx, | |
2743 | struct perf_event_context *ctx, | |
2744 | void *info) | |
04289bb9 | 2745 | { |
cdd6c482 | 2746 | struct perf_event *leader = event->group_leader; |
fae3fde6 | 2747 | struct perf_event_context *task_ctx; |
04289bb9 | 2748 | |
6e801e01 PZ |
2749 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2750 | event->state <= PERF_EVENT_STATE_ERROR) | |
fae3fde6 | 2751 | return; |
3cbed429 | 2752 | |
bd2afa49 PZ |
2753 | if (ctx->is_active) |
2754 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); | |
2755 | ||
0d3d73aa | 2756 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
04289bb9 | 2757 | |
fae3fde6 PZ |
2758 | if (!ctx->is_active) |
2759 | return; | |
2760 | ||
e5d1367f | 2761 | if (!event_filter_match(event)) { |
bd2afa49 | 2762 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); |
fae3fde6 | 2763 | return; |
e5d1367f | 2764 | } |
f4c4176f | 2765 | |
04289bb9 | 2766 | /* |
cdd6c482 | 2767 | * If the event is in a group and isn't the group leader, |
d859e29f | 2768 | * then don't put it on unless the group is on. |
04289bb9 | 2769 | */ |
bd2afa49 PZ |
2770 | if (leader != event && leader->state != PERF_EVENT_STATE_ACTIVE) { |
2771 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
fae3fde6 | 2772 | return; |
bd2afa49 | 2773 | } |
fe4b04fa | 2774 | |
fae3fde6 PZ |
2775 | task_ctx = cpuctx->task_ctx; |
2776 | if (ctx->task) | |
2777 | WARN_ON_ONCE(task_ctx != ctx); | |
d859e29f | 2778 | |
487f05e1 | 2779 | ctx_resched(cpuctx, task_ctx, get_event_type(event)); |
7b648018 PZ |
2780 | } |
2781 | ||
d859e29f | 2782 | /* |
788faab7 | 2783 | * Enable an event. |
c93f7669 | 2784 | * |
cdd6c482 IM |
2785 | * If event->ctx is a cloned context, callers must make sure that |
2786 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 2787 | * remains valid. This condition is satisfied when called through |
cdd6c482 IM |
2788 | * perf_event_for_each_child or perf_event_for_each as described |
2789 | * for perf_event_disable. | |
d859e29f | 2790 | */ |
f63a8daa | 2791 | static void _perf_event_enable(struct perf_event *event) |
d859e29f | 2792 | { |
cdd6c482 | 2793 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 2794 | |
7b648018 | 2795 | raw_spin_lock_irq(&ctx->lock); |
6e801e01 PZ |
2796 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2797 | event->state < PERF_EVENT_STATE_ERROR) { | |
7b648018 | 2798 | raw_spin_unlock_irq(&ctx->lock); |
d859e29f PM |
2799 | return; |
2800 | } | |
2801 | ||
d859e29f | 2802 | /* |
cdd6c482 | 2803 | * If the event is in error state, clear that first. |
7b648018 PZ |
2804 | * |
2805 | * That way, if we see the event in error state below, we know that it | |
2806 | * has gone back into error state, as distinct from the task having | |
2807 | * been scheduled away before the cross-call arrived. | |
d859e29f | 2808 | */ |
cdd6c482 IM |
2809 | if (event->state == PERF_EVENT_STATE_ERROR) |
2810 | event->state = PERF_EVENT_STATE_OFF; | |
e625cce1 | 2811 | raw_spin_unlock_irq(&ctx->lock); |
fe4b04fa | 2812 | |
fae3fde6 | 2813 | event_function_call(event, __perf_event_enable, NULL); |
d859e29f | 2814 | } |
f63a8daa PZ |
2815 | |
2816 | /* | |
2817 | * See perf_event_disable(); | |
2818 | */ | |
2819 | void perf_event_enable(struct perf_event *event) | |
2820 | { | |
2821 | struct perf_event_context *ctx; | |
2822 | ||
2823 | ctx = perf_event_ctx_lock(event); | |
2824 | _perf_event_enable(event); | |
2825 | perf_event_ctx_unlock(event, ctx); | |
2826 | } | |
dcfce4a0 | 2827 | EXPORT_SYMBOL_GPL(perf_event_enable); |
d859e29f | 2828 | |
375637bc AS |
2829 | struct stop_event_data { |
2830 | struct perf_event *event; | |
2831 | unsigned int restart; | |
2832 | }; | |
2833 | ||
95ff4ca2 AS |
2834 | static int __perf_event_stop(void *info) |
2835 | { | |
375637bc AS |
2836 | struct stop_event_data *sd = info; |
2837 | struct perf_event *event = sd->event; | |
95ff4ca2 | 2838 | |
375637bc | 2839 | /* if it's already INACTIVE, do nothing */ |
95ff4ca2 AS |
2840 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) |
2841 | return 0; | |
2842 | ||
2843 | /* matches smp_wmb() in event_sched_in() */ | |
2844 | smp_rmb(); | |
2845 | ||
2846 | /* | |
2847 | * There is a window with interrupts enabled before we get here, | |
2848 | * so we need to check again lest we try to stop another CPU's event. | |
2849 | */ | |
2850 | if (READ_ONCE(event->oncpu) != smp_processor_id()) | |
2851 | return -EAGAIN; | |
2852 | ||
2853 | event->pmu->stop(event, PERF_EF_UPDATE); | |
2854 | ||
375637bc AS |
2855 | /* |
2856 | * May race with the actual stop (through perf_pmu_output_stop()), | |
2857 | * but it is only used for events with AUX ring buffer, and such | |
2858 | * events will refuse to restart because of rb::aux_mmap_count==0, | |
2859 | * see comments in perf_aux_output_begin(). | |
2860 | * | |
788faab7 | 2861 | * Since this is happening on an event-local CPU, no trace is lost |
375637bc AS |
2862 | * while restarting. |
2863 | */ | |
2864 | if (sd->restart) | |
c9bbdd48 | 2865 | event->pmu->start(event, 0); |
375637bc | 2866 | |
95ff4ca2 AS |
2867 | return 0; |
2868 | } | |
2869 | ||
767ae086 | 2870 | static int perf_event_stop(struct perf_event *event, int restart) |
375637bc AS |
2871 | { |
2872 | struct stop_event_data sd = { | |
2873 | .event = event, | |
767ae086 | 2874 | .restart = restart, |
375637bc AS |
2875 | }; |
2876 | int ret = 0; | |
2877 | ||
2878 | do { | |
2879 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) | |
2880 | return 0; | |
2881 | ||
2882 | /* matches smp_wmb() in event_sched_in() */ | |
2883 | smp_rmb(); | |
2884 | ||
2885 | /* | |
2886 | * We only want to restart ACTIVE events, so if the event goes | |
2887 | * inactive here (event->oncpu==-1), there's nothing more to do; | |
2888 | * fall through with ret==-ENXIO. | |
2889 | */ | |
2890 | ret = cpu_function_call(READ_ONCE(event->oncpu), | |
2891 | __perf_event_stop, &sd); | |
2892 | } while (ret == -EAGAIN); | |
2893 | ||
2894 | return ret; | |
2895 | } | |
2896 | ||
2897 | /* | |
2898 | * In order to contain the amount of racy and tricky in the address filter | |
2899 | * configuration management, it is a two part process: | |
2900 | * | |
2901 | * (p1) when userspace mappings change as a result of (1) or (2) or (3) below, | |
2902 | * we update the addresses of corresponding vmas in | |
c60f83b8 | 2903 | * event::addr_filter_ranges array and bump the event::addr_filters_gen; |
375637bc AS |
2904 | * (p2) when an event is scheduled in (pmu::add), it calls |
2905 | * perf_event_addr_filters_sync() which calls pmu::addr_filters_sync() | |
2906 | * if the generation has changed since the previous call. | |
2907 | * | |
2908 | * If (p1) happens while the event is active, we restart it to force (p2). | |
2909 | * | |
2910 | * (1) perf_addr_filters_apply(): adjusting filters' offsets based on | |
2911 | * pre-existing mappings, called once when new filters arrive via SET_FILTER | |
2912 | * ioctl; | |
2913 | * (2) perf_addr_filters_adjust(): adjusting filters' offsets based on newly | |
2914 | * registered mapping, called for every new mmap(), with mm::mmap_sem down | |
2915 | * for reading; | |
2916 | * (3) perf_event_addr_filters_exec(): clearing filters' offsets in the process | |
2917 | * of exec. | |
2918 | */ | |
2919 | void perf_event_addr_filters_sync(struct perf_event *event) | |
2920 | { | |
2921 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
2922 | ||
2923 | if (!has_addr_filter(event)) | |
2924 | return; | |
2925 | ||
2926 | raw_spin_lock(&ifh->lock); | |
2927 | if (event->addr_filters_gen != event->hw.addr_filters_gen) { | |
2928 | event->pmu->addr_filters_sync(event); | |
2929 | event->hw.addr_filters_gen = event->addr_filters_gen; | |
2930 | } | |
2931 | raw_spin_unlock(&ifh->lock); | |
2932 | } | |
2933 | EXPORT_SYMBOL_GPL(perf_event_addr_filters_sync); | |
2934 | ||
f63a8daa | 2935 | static int _perf_event_refresh(struct perf_event *event, int refresh) |
79f14641 | 2936 | { |
2023b359 | 2937 | /* |
cdd6c482 | 2938 | * not supported on inherited events |
2023b359 | 2939 | */ |
2e939d1d | 2940 | if (event->attr.inherit || !is_sampling_event(event)) |
2023b359 PZ |
2941 | return -EINVAL; |
2942 | ||
cdd6c482 | 2943 | atomic_add(refresh, &event->event_limit); |
f63a8daa | 2944 | _perf_event_enable(event); |
2023b359 PZ |
2945 | |
2946 | return 0; | |
79f14641 | 2947 | } |
f63a8daa PZ |
2948 | |
2949 | /* | |
2950 | * See perf_event_disable() | |
2951 | */ | |
2952 | int perf_event_refresh(struct perf_event *event, int refresh) | |
2953 | { | |
2954 | struct perf_event_context *ctx; | |
2955 | int ret; | |
2956 | ||
2957 | ctx = perf_event_ctx_lock(event); | |
2958 | ret = _perf_event_refresh(event, refresh); | |
2959 | perf_event_ctx_unlock(event, ctx); | |
2960 | ||
2961 | return ret; | |
2962 | } | |
26ca5c11 | 2963 | EXPORT_SYMBOL_GPL(perf_event_refresh); |
79f14641 | 2964 | |
32ff77e8 MC |
2965 | static int perf_event_modify_breakpoint(struct perf_event *bp, |
2966 | struct perf_event_attr *attr) | |
2967 | { | |
2968 | int err; | |
2969 | ||
2970 | _perf_event_disable(bp); | |
2971 | ||
2972 | err = modify_user_hw_breakpoint_check(bp, attr, true); | |
32ff77e8 | 2973 | |
bf06278c | 2974 | if (!bp->attr.disabled) |
32ff77e8 | 2975 | _perf_event_enable(bp); |
bf06278c JO |
2976 | |
2977 | return err; | |
32ff77e8 MC |
2978 | } |
2979 | ||
2980 | static int perf_event_modify_attr(struct perf_event *event, | |
2981 | struct perf_event_attr *attr) | |
2982 | { | |
2983 | if (event->attr.type != attr->type) | |
2984 | return -EINVAL; | |
2985 | ||
2986 | switch (event->attr.type) { | |
2987 | case PERF_TYPE_BREAKPOINT: | |
2988 | return perf_event_modify_breakpoint(event, attr); | |
2989 | default: | |
2990 | /* Place holder for future additions. */ | |
2991 | return -EOPNOTSUPP; | |
2992 | } | |
2993 | } | |
2994 | ||
5b0311e1 FW |
2995 | static void ctx_sched_out(struct perf_event_context *ctx, |
2996 | struct perf_cpu_context *cpuctx, | |
2997 | enum event_type_t event_type) | |
235c7fc7 | 2998 | { |
6668128a | 2999 | struct perf_event *event, *tmp; |
db24d33e | 3000 | int is_active = ctx->is_active; |
235c7fc7 | 3001 | |
c994d613 | 3002 | lockdep_assert_held(&ctx->lock); |
235c7fc7 | 3003 | |
39a43640 PZ |
3004 | if (likely(!ctx->nr_events)) { |
3005 | /* | |
3006 | * See __perf_remove_from_context(). | |
3007 | */ | |
3008 | WARN_ON_ONCE(ctx->is_active); | |
3009 | if (ctx->task) | |
3010 | WARN_ON_ONCE(cpuctx->task_ctx); | |
facc4307 | 3011 | return; |
39a43640 PZ |
3012 | } |
3013 | ||
db24d33e | 3014 | ctx->is_active &= ~event_type; |
3cbaa590 PZ |
3015 | if (!(ctx->is_active & EVENT_ALL)) |
3016 | ctx->is_active = 0; | |
3017 | ||
63e30d3e PZ |
3018 | if (ctx->task) { |
3019 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
3020 | if (!ctx->is_active) | |
3021 | cpuctx->task_ctx = NULL; | |
3022 | } | |
facc4307 | 3023 | |
8fdc6539 PZ |
3024 | /* |
3025 | * Always update time if it was set; not only when it changes. | |
3026 | * Otherwise we can 'forget' to update time for any but the last | |
3027 | * context we sched out. For example: | |
3028 | * | |
3029 | * ctx_sched_out(.event_type = EVENT_FLEXIBLE) | |
3030 | * ctx_sched_out(.event_type = EVENT_PINNED) | |
3031 | * | |
3032 | * would only update time for the pinned events. | |
3033 | */ | |
3cbaa590 PZ |
3034 | if (is_active & EVENT_TIME) { |
3035 | /* update (and stop) ctx time */ | |
3036 | update_context_time(ctx); | |
3037 | update_cgrp_time_from_cpuctx(cpuctx); | |
3038 | } | |
3039 | ||
8fdc6539 PZ |
3040 | is_active ^= ctx->is_active; /* changed bits */ |
3041 | ||
3cbaa590 | 3042 | if (!ctx->nr_active || !(is_active & EVENT_ALL)) |
facc4307 | 3043 | return; |
5b0311e1 | 3044 | |
fd7d5517 IR |
3045 | /* |
3046 | * If we had been multiplexing, no rotations are necessary, now no events | |
3047 | * are active. | |
3048 | */ | |
3049 | ctx->rotate_necessary = 0; | |
3050 | ||
075e0b00 | 3051 | perf_pmu_disable(ctx->pmu); |
3cbaa590 | 3052 | if (is_active & EVENT_PINNED) { |
6668128a | 3053 | list_for_each_entry_safe(event, tmp, &ctx->pinned_active, active_list) |
889ff015 | 3054 | group_sched_out(event, cpuctx, ctx); |
9ed6060d | 3055 | } |
889ff015 | 3056 | |
3cbaa590 | 3057 | if (is_active & EVENT_FLEXIBLE) { |
6668128a | 3058 | list_for_each_entry_safe(event, tmp, &ctx->flexible_active, active_list) |
8c9ed8e1 | 3059 | group_sched_out(event, cpuctx, ctx); |
9ed6060d | 3060 | } |
1b9a644f | 3061 | perf_pmu_enable(ctx->pmu); |
235c7fc7 IM |
3062 | } |
3063 | ||
564c2b21 | 3064 | /* |
5a3126d4 PZ |
3065 | * Test whether two contexts are equivalent, i.e. whether they have both been |
3066 | * cloned from the same version of the same context. | |
3067 | * | |
3068 | * Equivalence is measured using a generation number in the context that is | |
3069 | * incremented on each modification to it; see unclone_ctx(), list_add_event() | |
3070 | * and list_del_event(). | |
564c2b21 | 3071 | */ |
cdd6c482 IM |
3072 | static int context_equiv(struct perf_event_context *ctx1, |
3073 | struct perf_event_context *ctx2) | |
564c2b21 | 3074 | { |
211de6eb PZ |
3075 | lockdep_assert_held(&ctx1->lock); |
3076 | lockdep_assert_held(&ctx2->lock); | |
3077 | ||
5a3126d4 PZ |
3078 | /* Pinning disables the swap optimization */ |
3079 | if (ctx1->pin_count || ctx2->pin_count) | |
3080 | return 0; | |
3081 | ||
3082 | /* If ctx1 is the parent of ctx2 */ | |
3083 | if (ctx1 == ctx2->parent_ctx && ctx1->generation == ctx2->parent_gen) | |
3084 | return 1; | |
3085 | ||
3086 | /* If ctx2 is the parent of ctx1 */ | |
3087 | if (ctx1->parent_ctx == ctx2 && ctx1->parent_gen == ctx2->generation) | |
3088 | return 1; | |
3089 | ||
3090 | /* | |
3091 | * If ctx1 and ctx2 have the same parent; we flatten the parent | |
3092 | * hierarchy, see perf_event_init_context(). | |
3093 | */ | |
3094 | if (ctx1->parent_ctx && ctx1->parent_ctx == ctx2->parent_ctx && | |
3095 | ctx1->parent_gen == ctx2->parent_gen) | |
3096 | return 1; | |
3097 | ||
3098 | /* Unmatched */ | |
3099 | return 0; | |
564c2b21 PM |
3100 | } |
3101 | ||
cdd6c482 IM |
3102 | static void __perf_event_sync_stat(struct perf_event *event, |
3103 | struct perf_event *next_event) | |
bfbd3381 PZ |
3104 | { |
3105 | u64 value; | |
3106 | ||
cdd6c482 | 3107 | if (!event->attr.inherit_stat) |
bfbd3381 PZ |
3108 | return; |
3109 | ||
3110 | /* | |
cdd6c482 | 3111 | * Update the event value, we cannot use perf_event_read() |
bfbd3381 PZ |
3112 | * because we're in the middle of a context switch and have IRQs |
3113 | * disabled, which upsets smp_call_function_single(), however | |
cdd6c482 | 3114 | * we know the event must be on the current CPU, therefore we |
bfbd3381 PZ |
3115 | * don't need to use it. |
3116 | */ | |
0d3d73aa | 3117 | if (event->state == PERF_EVENT_STATE_ACTIVE) |
3dbebf15 | 3118 | event->pmu->read(event); |
bfbd3381 | 3119 | |
0d3d73aa | 3120 | perf_event_update_time(event); |
bfbd3381 PZ |
3121 | |
3122 | /* | |
cdd6c482 | 3123 | * In order to keep per-task stats reliable we need to flip the event |
bfbd3381 PZ |
3124 | * values when we flip the contexts. |
3125 | */ | |
e7850595 PZ |
3126 | value = local64_read(&next_event->count); |
3127 | value = local64_xchg(&event->count, value); | |
3128 | local64_set(&next_event->count, value); | |
bfbd3381 | 3129 | |
cdd6c482 IM |
3130 | swap(event->total_time_enabled, next_event->total_time_enabled); |
3131 | swap(event->total_time_running, next_event->total_time_running); | |
19d2e755 | 3132 | |
bfbd3381 | 3133 | /* |
19d2e755 | 3134 | * Since we swizzled the values, update the user visible data too. |
bfbd3381 | 3135 | */ |
cdd6c482 IM |
3136 | perf_event_update_userpage(event); |
3137 | perf_event_update_userpage(next_event); | |
bfbd3381 PZ |
3138 | } |
3139 | ||
cdd6c482 IM |
3140 | static void perf_event_sync_stat(struct perf_event_context *ctx, |
3141 | struct perf_event_context *next_ctx) | |
bfbd3381 | 3142 | { |
cdd6c482 | 3143 | struct perf_event *event, *next_event; |
bfbd3381 PZ |
3144 | |
3145 | if (!ctx->nr_stat) | |
3146 | return; | |
3147 | ||
02ffdbc8 PZ |
3148 | update_context_time(ctx); |
3149 | ||
cdd6c482 IM |
3150 | event = list_first_entry(&ctx->event_list, |
3151 | struct perf_event, event_entry); | |
bfbd3381 | 3152 | |
cdd6c482 IM |
3153 | next_event = list_first_entry(&next_ctx->event_list, |
3154 | struct perf_event, event_entry); | |
bfbd3381 | 3155 | |
cdd6c482 IM |
3156 | while (&event->event_entry != &ctx->event_list && |
3157 | &next_event->event_entry != &next_ctx->event_list) { | |
bfbd3381 | 3158 | |
cdd6c482 | 3159 | __perf_event_sync_stat(event, next_event); |
bfbd3381 | 3160 | |
cdd6c482 IM |
3161 | event = list_next_entry(event, event_entry); |
3162 | next_event = list_next_entry(next_event, event_entry); | |
bfbd3381 PZ |
3163 | } |
3164 | } | |
3165 | ||
fe4b04fa PZ |
3166 | static void perf_event_context_sched_out(struct task_struct *task, int ctxn, |
3167 | struct task_struct *next) | |
0793a61d | 3168 | { |
8dc85d54 | 3169 | struct perf_event_context *ctx = task->perf_event_ctxp[ctxn]; |
cdd6c482 | 3170 | struct perf_event_context *next_ctx; |
5a3126d4 | 3171 | struct perf_event_context *parent, *next_parent; |
108b02cf | 3172 | struct perf_cpu_context *cpuctx; |
c93f7669 | 3173 | int do_switch = 1; |
0793a61d | 3174 | |
108b02cf PZ |
3175 | if (likely(!ctx)) |
3176 | return; | |
10989fb2 | 3177 | |
108b02cf PZ |
3178 | cpuctx = __get_cpu_context(ctx); |
3179 | if (!cpuctx->task_ctx) | |
0793a61d TG |
3180 | return; |
3181 | ||
c93f7669 | 3182 | rcu_read_lock(); |
8dc85d54 | 3183 | next_ctx = next->perf_event_ctxp[ctxn]; |
5a3126d4 PZ |
3184 | if (!next_ctx) |
3185 | goto unlock; | |
3186 | ||
3187 | parent = rcu_dereference(ctx->parent_ctx); | |
3188 | next_parent = rcu_dereference(next_ctx->parent_ctx); | |
3189 | ||
3190 | /* If neither context have a parent context; they cannot be clones. */ | |
802c8a61 | 3191 | if (!parent && !next_parent) |
5a3126d4 PZ |
3192 | goto unlock; |
3193 | ||
3194 | if (next_parent == ctx || next_ctx == parent || next_parent == parent) { | |
c93f7669 PM |
3195 | /* |
3196 | * Looks like the two contexts are clones, so we might be | |
3197 | * able to optimize the context switch. We lock both | |
3198 | * contexts and check that they are clones under the | |
3199 | * lock (including re-checking that neither has been | |
3200 | * uncloned in the meantime). It doesn't matter which | |
3201 | * order we take the locks because no other cpu could | |
3202 | * be trying to lock both of these tasks. | |
3203 | */ | |
e625cce1 TG |
3204 | raw_spin_lock(&ctx->lock); |
3205 | raw_spin_lock_nested(&next_ctx->lock, SINGLE_DEPTH_NESTING); | |
c93f7669 | 3206 | if (context_equiv(ctx, next_ctx)) { |
63b6da39 PZ |
3207 | WRITE_ONCE(ctx->task, next); |
3208 | WRITE_ONCE(next_ctx->task, task); | |
5a158c3c YZ |
3209 | |
3210 | swap(ctx->task_ctx_data, next_ctx->task_ctx_data); | |
3211 | ||
63b6da39 PZ |
3212 | /* |
3213 | * RCU_INIT_POINTER here is safe because we've not | |
3214 | * modified the ctx and the above modification of | |
3215 | * ctx->task and ctx->task_ctx_data are immaterial | |
3216 | * since those values are always verified under | |
3217 | * ctx->lock which we're now holding. | |
3218 | */ | |
3219 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], next_ctx); | |
3220 | RCU_INIT_POINTER(next->perf_event_ctxp[ctxn], ctx); | |
3221 | ||
c93f7669 | 3222 | do_switch = 0; |
bfbd3381 | 3223 | |
cdd6c482 | 3224 | perf_event_sync_stat(ctx, next_ctx); |
c93f7669 | 3225 | } |
e625cce1 TG |
3226 | raw_spin_unlock(&next_ctx->lock); |
3227 | raw_spin_unlock(&ctx->lock); | |
564c2b21 | 3228 | } |
5a3126d4 | 3229 | unlock: |
c93f7669 | 3230 | rcu_read_unlock(); |
564c2b21 | 3231 | |
c93f7669 | 3232 | if (do_switch) { |
facc4307 | 3233 | raw_spin_lock(&ctx->lock); |
487f05e1 | 3234 | task_ctx_sched_out(cpuctx, ctx, EVENT_ALL); |
facc4307 | 3235 | raw_spin_unlock(&ctx->lock); |
c93f7669 | 3236 | } |
0793a61d TG |
3237 | } |
3238 | ||
e48c1788 PZ |
3239 | static DEFINE_PER_CPU(struct list_head, sched_cb_list); |
3240 | ||
ba532500 YZ |
3241 | void perf_sched_cb_dec(struct pmu *pmu) |
3242 | { | |
e48c1788 PZ |
3243 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
3244 | ||
ba532500 | 3245 | this_cpu_dec(perf_sched_cb_usages); |
e48c1788 PZ |
3246 | |
3247 | if (!--cpuctx->sched_cb_usage) | |
3248 | list_del(&cpuctx->sched_cb_entry); | |
ba532500 YZ |
3249 | } |
3250 | ||
e48c1788 | 3251 | |
ba532500 YZ |
3252 | void perf_sched_cb_inc(struct pmu *pmu) |
3253 | { | |
e48c1788 PZ |
3254 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
3255 | ||
3256 | if (!cpuctx->sched_cb_usage++) | |
3257 | list_add(&cpuctx->sched_cb_entry, this_cpu_ptr(&sched_cb_list)); | |
3258 | ||
ba532500 YZ |
3259 | this_cpu_inc(perf_sched_cb_usages); |
3260 | } | |
3261 | ||
3262 | /* | |
3263 | * This function provides the context switch callback to the lower code | |
3264 | * layer. It is invoked ONLY when the context switch callback is enabled. | |
09e61b4f PZ |
3265 | * |
3266 | * This callback is relevant even to per-cpu events; for example multi event | |
3267 | * PEBS requires this to provide PID/TID information. This requires we flush | |
3268 | * all queued PEBS records before we context switch to a new task. | |
ba532500 YZ |
3269 | */ |
3270 | static void perf_pmu_sched_task(struct task_struct *prev, | |
3271 | struct task_struct *next, | |
3272 | bool sched_in) | |
3273 | { | |
3274 | struct perf_cpu_context *cpuctx; | |
3275 | struct pmu *pmu; | |
ba532500 YZ |
3276 | |
3277 | if (prev == next) | |
3278 | return; | |
3279 | ||
e48c1788 | 3280 | list_for_each_entry(cpuctx, this_cpu_ptr(&sched_cb_list), sched_cb_entry) { |
1fd7e416 | 3281 | pmu = cpuctx->ctx.pmu; /* software PMUs will not have sched_task */ |
ba532500 | 3282 | |
e48c1788 PZ |
3283 | if (WARN_ON_ONCE(!pmu->sched_task)) |
3284 | continue; | |
ba532500 | 3285 | |
e48c1788 PZ |
3286 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
3287 | perf_pmu_disable(pmu); | |
ba532500 | 3288 | |
e48c1788 | 3289 | pmu->sched_task(cpuctx->task_ctx, sched_in); |
ba532500 | 3290 | |
e48c1788 PZ |
3291 | perf_pmu_enable(pmu); |
3292 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
ba532500 | 3293 | } |
ba532500 YZ |
3294 | } |
3295 | ||
45ac1403 AH |
3296 | static void perf_event_switch(struct task_struct *task, |
3297 | struct task_struct *next_prev, bool sched_in); | |
3298 | ||
8dc85d54 PZ |
3299 | #define for_each_task_context_nr(ctxn) \ |
3300 | for ((ctxn) = 0; (ctxn) < perf_nr_task_contexts; (ctxn)++) | |
3301 | ||
3302 | /* | |
3303 | * Called from scheduler to remove the events of the current task, | |
3304 | * with interrupts disabled. | |
3305 | * | |
3306 | * We stop each event and update the event value in event->count. | |
3307 | * | |
3308 | * This does not protect us against NMI, but disable() | |
3309 | * sets the disabled bit in the control field of event _before_ | |
3310 | * accessing the event control register. If a NMI hits, then it will | |
3311 | * not restart the event. | |
3312 | */ | |
ab0cce56 JO |
3313 | void __perf_event_task_sched_out(struct task_struct *task, |
3314 | struct task_struct *next) | |
8dc85d54 PZ |
3315 | { |
3316 | int ctxn; | |
3317 | ||
ba532500 YZ |
3318 | if (__this_cpu_read(perf_sched_cb_usages)) |
3319 | perf_pmu_sched_task(task, next, false); | |
3320 | ||
45ac1403 AH |
3321 | if (atomic_read(&nr_switch_events)) |
3322 | perf_event_switch(task, next, false); | |
3323 | ||
8dc85d54 PZ |
3324 | for_each_task_context_nr(ctxn) |
3325 | perf_event_context_sched_out(task, ctxn, next); | |
e5d1367f SE |
3326 | |
3327 | /* | |
3328 | * if cgroup events exist on this CPU, then we need | |
3329 | * to check if we have to switch out PMU state. | |
3330 | * cgroup event are system-wide mode only | |
3331 | */ | |
4a32fea9 | 3332 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) |
a8d757ef | 3333 | perf_cgroup_sched_out(task, next); |
8dc85d54 PZ |
3334 | } |
3335 | ||
5b0311e1 FW |
3336 | /* |
3337 | * Called with IRQs disabled | |
3338 | */ | |
3339 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, | |
3340 | enum event_type_t event_type) | |
3341 | { | |
3342 | ctx_sched_out(&cpuctx->ctx, cpuctx, event_type); | |
04289bb9 IM |
3343 | } |
3344 | ||
1cac7b1a PZ |
3345 | static int visit_groups_merge(struct perf_event_groups *groups, int cpu, |
3346 | int (*func)(struct perf_event *, void *), void *data) | |
0793a61d | 3347 | { |
1cac7b1a PZ |
3348 | struct perf_event **evt, *evt1, *evt2; |
3349 | int ret; | |
8e1a2031 | 3350 | |
1cac7b1a PZ |
3351 | evt1 = perf_event_groups_first(groups, -1); |
3352 | evt2 = perf_event_groups_first(groups, cpu); | |
3353 | ||
3354 | while (evt1 || evt2) { | |
3355 | if (evt1 && evt2) { | |
3356 | if (evt1->group_index < evt2->group_index) | |
3357 | evt = &evt1; | |
3358 | else | |
3359 | evt = &evt2; | |
3360 | } else if (evt1) { | |
3361 | evt = &evt1; | |
3362 | } else { | |
3363 | evt = &evt2; | |
8e1a2031 | 3364 | } |
1cac7b1a PZ |
3365 | |
3366 | ret = func(*evt, data); | |
3367 | if (ret) | |
3368 | return ret; | |
3369 | ||
3370 | *evt = perf_event_groups_next(*evt); | |
8e1a2031 | 3371 | } |
0793a61d | 3372 | |
1cac7b1a PZ |
3373 | return 0; |
3374 | } | |
3375 | ||
3376 | struct sched_in_data { | |
3377 | struct perf_event_context *ctx; | |
3378 | struct perf_cpu_context *cpuctx; | |
3379 | int can_add_hw; | |
3380 | }; | |
3381 | ||
3382 | static int pinned_sched_in(struct perf_event *event, void *data) | |
3383 | { | |
3384 | struct sched_in_data *sid = data; | |
3385 | ||
3386 | if (event->state <= PERF_EVENT_STATE_OFF) | |
3387 | return 0; | |
3388 | ||
3389 | if (!event_filter_match(event)) | |
3390 | return 0; | |
3391 | ||
6668128a PZ |
3392 | if (group_can_go_on(event, sid->cpuctx, sid->can_add_hw)) { |
3393 | if (!group_sched_in(event, sid->cpuctx, sid->ctx)) | |
3394 | list_add_tail(&event->active_list, &sid->ctx->pinned_active); | |
3395 | } | |
1cac7b1a PZ |
3396 | |
3397 | /* | |
3398 | * If this pinned group hasn't been scheduled, | |
3399 | * put it in error state. | |
3400 | */ | |
3401 | if (event->state == PERF_EVENT_STATE_INACTIVE) | |
3402 | perf_event_set_state(event, PERF_EVENT_STATE_ERROR); | |
3403 | ||
3404 | return 0; | |
3405 | } | |
3406 | ||
3407 | static int flexible_sched_in(struct perf_event *event, void *data) | |
3408 | { | |
3409 | struct sched_in_data *sid = data; | |
3410 | ||
3411 | if (event->state <= PERF_EVENT_STATE_OFF) | |
3412 | return 0; | |
3413 | ||
3414 | if (!event_filter_match(event)) | |
3415 | return 0; | |
3416 | ||
3417 | if (group_can_go_on(event, sid->cpuctx, sid->can_add_hw)) { | |
fd7d5517 IR |
3418 | int ret = group_sched_in(event, sid->cpuctx, sid->ctx); |
3419 | if (ret) { | |
1cac7b1a | 3420 | sid->can_add_hw = 0; |
fd7d5517 IR |
3421 | sid->ctx->rotate_necessary = 1; |
3422 | return 0; | |
3423 | } | |
3424 | list_add_tail(&event->active_list, &sid->ctx->flexible_active); | |
3b6f9e5c | 3425 | } |
1cac7b1a PZ |
3426 | |
3427 | return 0; | |
5b0311e1 FW |
3428 | } |
3429 | ||
3430 | static void | |
1cac7b1a PZ |
3431 | ctx_pinned_sched_in(struct perf_event_context *ctx, |
3432 | struct perf_cpu_context *cpuctx) | |
5b0311e1 | 3433 | { |
1cac7b1a PZ |
3434 | struct sched_in_data sid = { |
3435 | .ctx = ctx, | |
3436 | .cpuctx = cpuctx, | |
3437 | .can_add_hw = 1, | |
3438 | }; | |
3b6f9e5c | 3439 | |
1cac7b1a PZ |
3440 | visit_groups_merge(&ctx->pinned_groups, |
3441 | smp_processor_id(), | |
3442 | pinned_sched_in, &sid); | |
3443 | } | |
8e1a2031 | 3444 | |
1cac7b1a PZ |
3445 | static void |
3446 | ctx_flexible_sched_in(struct perf_event_context *ctx, | |
3447 | struct perf_cpu_context *cpuctx) | |
3448 | { | |
3449 | struct sched_in_data sid = { | |
3450 | .ctx = ctx, | |
3451 | .cpuctx = cpuctx, | |
3452 | .can_add_hw = 1, | |
3453 | }; | |
0793a61d | 3454 | |
1cac7b1a PZ |
3455 | visit_groups_merge(&ctx->flexible_groups, |
3456 | smp_processor_id(), | |
3457 | flexible_sched_in, &sid); | |
5b0311e1 FW |
3458 | } |
3459 | ||
3460 | static void | |
3461 | ctx_sched_in(struct perf_event_context *ctx, | |
3462 | struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
3463 | enum event_type_t event_type, |
3464 | struct task_struct *task) | |
5b0311e1 | 3465 | { |
db24d33e | 3466 | int is_active = ctx->is_active; |
c994d613 PZ |
3467 | u64 now; |
3468 | ||
3469 | lockdep_assert_held(&ctx->lock); | |
e5d1367f | 3470 | |
5b0311e1 | 3471 | if (likely(!ctx->nr_events)) |
facc4307 | 3472 | return; |
5b0311e1 | 3473 | |
3cbaa590 | 3474 | ctx->is_active |= (event_type | EVENT_TIME); |
63e30d3e PZ |
3475 | if (ctx->task) { |
3476 | if (!is_active) | |
3477 | cpuctx->task_ctx = ctx; | |
3478 | else | |
3479 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
3480 | } | |
3481 | ||
3cbaa590 PZ |
3482 | is_active ^= ctx->is_active; /* changed bits */ |
3483 | ||
3484 | if (is_active & EVENT_TIME) { | |
3485 | /* start ctx time */ | |
3486 | now = perf_clock(); | |
3487 | ctx->timestamp = now; | |
3488 | perf_cgroup_set_timestamp(task, ctx); | |
3489 | } | |
3490 | ||
5b0311e1 FW |
3491 | /* |
3492 | * First go through the list and put on any pinned groups | |
3493 | * in order to give them the best chance of going on. | |
3494 | */ | |
3cbaa590 | 3495 | if (is_active & EVENT_PINNED) |
6e37738a | 3496 | ctx_pinned_sched_in(ctx, cpuctx); |
5b0311e1 FW |
3497 | |
3498 | /* Then walk through the lower prio flexible groups */ | |
3cbaa590 | 3499 | if (is_active & EVENT_FLEXIBLE) |
6e37738a | 3500 | ctx_flexible_sched_in(ctx, cpuctx); |
235c7fc7 IM |
3501 | } |
3502 | ||
329c0e01 | 3503 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, |
e5d1367f SE |
3504 | enum event_type_t event_type, |
3505 | struct task_struct *task) | |
329c0e01 FW |
3506 | { |
3507 | struct perf_event_context *ctx = &cpuctx->ctx; | |
3508 | ||
e5d1367f | 3509 | ctx_sched_in(ctx, cpuctx, event_type, task); |
329c0e01 FW |
3510 | } |
3511 | ||
e5d1367f SE |
3512 | static void perf_event_context_sched_in(struct perf_event_context *ctx, |
3513 | struct task_struct *task) | |
235c7fc7 | 3514 | { |
108b02cf | 3515 | struct perf_cpu_context *cpuctx; |
235c7fc7 | 3516 | |
108b02cf | 3517 | cpuctx = __get_cpu_context(ctx); |
329c0e01 FW |
3518 | if (cpuctx->task_ctx == ctx) |
3519 | return; | |
3520 | ||
facc4307 | 3521 | perf_ctx_lock(cpuctx, ctx); |
fdccc3fb | 3522 | /* |
3523 | * We must check ctx->nr_events while holding ctx->lock, such | |
3524 | * that we serialize against perf_install_in_context(). | |
3525 | */ | |
3526 | if (!ctx->nr_events) | |
3527 | goto unlock; | |
3528 | ||
1b9a644f | 3529 | perf_pmu_disable(ctx->pmu); |
329c0e01 FW |
3530 | /* |
3531 | * We want to keep the following priority order: | |
3532 | * cpu pinned (that don't need to move), task pinned, | |
3533 | * cpu flexible, task flexible. | |
fe45bafb AS |
3534 | * |
3535 | * However, if task's ctx is not carrying any pinned | |
3536 | * events, no need to flip the cpuctx's events around. | |
329c0e01 | 3537 | */ |
8e1a2031 | 3538 | if (!RB_EMPTY_ROOT(&ctx->pinned_groups.tree)) |
fe45bafb | 3539 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); |
63e30d3e | 3540 | perf_event_sched_in(cpuctx, ctx, task); |
facc4307 | 3541 | perf_pmu_enable(ctx->pmu); |
fdccc3fb | 3542 | |
3543 | unlock: | |
facc4307 | 3544 | perf_ctx_unlock(cpuctx, ctx); |
235c7fc7 IM |
3545 | } |
3546 | ||
8dc85d54 PZ |
3547 | /* |
3548 | * Called from scheduler to add the events of the current task | |
3549 | * with interrupts disabled. | |
3550 | * | |
3551 | * We restore the event value and then enable it. | |
3552 | * | |
3553 | * This does not protect us against NMI, but enable() | |
3554 | * sets the enabled bit in the control field of event _before_ | |
3555 | * accessing the event control register. If a NMI hits, then it will | |
3556 | * keep the event running. | |
3557 | */ | |
ab0cce56 JO |
3558 | void __perf_event_task_sched_in(struct task_struct *prev, |
3559 | struct task_struct *task) | |
8dc85d54 PZ |
3560 | { |
3561 | struct perf_event_context *ctx; | |
3562 | int ctxn; | |
3563 | ||
7e41d177 PZ |
3564 | /* |
3565 | * If cgroup events exist on this CPU, then we need to check if we have | |
3566 | * to switch in PMU state; cgroup event are system-wide mode only. | |
3567 | * | |
3568 | * Since cgroup events are CPU events, we must schedule these in before | |
3569 | * we schedule in the task events. | |
3570 | */ | |
3571 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) | |
3572 | perf_cgroup_sched_in(prev, task); | |
3573 | ||
8dc85d54 PZ |
3574 | for_each_task_context_nr(ctxn) { |
3575 | ctx = task->perf_event_ctxp[ctxn]; | |
3576 | if (likely(!ctx)) | |
3577 | continue; | |
3578 | ||
e5d1367f | 3579 | perf_event_context_sched_in(ctx, task); |
8dc85d54 | 3580 | } |
d010b332 | 3581 | |
45ac1403 AH |
3582 | if (atomic_read(&nr_switch_events)) |
3583 | perf_event_switch(task, prev, true); | |
3584 | ||
ba532500 YZ |
3585 | if (__this_cpu_read(perf_sched_cb_usages)) |
3586 | perf_pmu_sched_task(prev, task, true); | |
235c7fc7 IM |
3587 | } |
3588 | ||
abd50713 PZ |
3589 | static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count) |
3590 | { | |
3591 | u64 frequency = event->attr.sample_freq; | |
3592 | u64 sec = NSEC_PER_SEC; | |
3593 | u64 divisor, dividend; | |
3594 | ||
3595 | int count_fls, nsec_fls, frequency_fls, sec_fls; | |
3596 | ||
3597 | count_fls = fls64(count); | |
3598 | nsec_fls = fls64(nsec); | |
3599 | frequency_fls = fls64(frequency); | |
3600 | sec_fls = 30; | |
3601 | ||
3602 | /* | |
3603 | * We got @count in @nsec, with a target of sample_freq HZ | |
3604 | * the target period becomes: | |
3605 | * | |
3606 | * @count * 10^9 | |
3607 | * period = ------------------- | |
3608 | * @nsec * sample_freq | |
3609 | * | |
3610 | */ | |
3611 | ||
3612 | /* | |
3613 | * Reduce accuracy by one bit such that @a and @b converge | |
3614 | * to a similar magnitude. | |
3615 | */ | |
fe4b04fa | 3616 | #define REDUCE_FLS(a, b) \ |
abd50713 PZ |
3617 | do { \ |
3618 | if (a##_fls > b##_fls) { \ | |
3619 | a >>= 1; \ | |
3620 | a##_fls--; \ | |
3621 | } else { \ | |
3622 | b >>= 1; \ | |
3623 | b##_fls--; \ | |
3624 | } \ | |
3625 | } while (0) | |
3626 | ||
3627 | /* | |
3628 | * Reduce accuracy until either term fits in a u64, then proceed with | |
3629 | * the other, so that finally we can do a u64/u64 division. | |
3630 | */ | |
3631 | while (count_fls + sec_fls > 64 && nsec_fls + frequency_fls > 64) { | |
3632 | REDUCE_FLS(nsec, frequency); | |
3633 | REDUCE_FLS(sec, count); | |
3634 | } | |
3635 | ||
3636 | if (count_fls + sec_fls > 64) { | |
3637 | divisor = nsec * frequency; | |
3638 | ||
3639 | while (count_fls + sec_fls > 64) { | |
3640 | REDUCE_FLS(count, sec); | |
3641 | divisor >>= 1; | |
3642 | } | |
3643 | ||
3644 | dividend = count * sec; | |
3645 | } else { | |
3646 | dividend = count * sec; | |
3647 | ||
3648 | while (nsec_fls + frequency_fls > 64) { | |
3649 | REDUCE_FLS(nsec, frequency); | |
3650 | dividend >>= 1; | |
3651 | } | |
3652 | ||
3653 | divisor = nsec * frequency; | |
3654 | } | |
3655 | ||
f6ab91ad PZ |
3656 | if (!divisor) |
3657 | return dividend; | |
3658 | ||
abd50713 PZ |
3659 | return div64_u64(dividend, divisor); |
3660 | } | |
3661 | ||
e050e3f0 SE |
3662 | static DEFINE_PER_CPU(int, perf_throttled_count); |
3663 | static DEFINE_PER_CPU(u64, perf_throttled_seq); | |
3664 | ||
f39d47ff | 3665 | static void perf_adjust_period(struct perf_event *event, u64 nsec, u64 count, bool disable) |
bd2b5b12 | 3666 | { |
cdd6c482 | 3667 | struct hw_perf_event *hwc = &event->hw; |
f6ab91ad | 3668 | s64 period, sample_period; |
bd2b5b12 PZ |
3669 | s64 delta; |
3670 | ||
abd50713 | 3671 | period = perf_calculate_period(event, nsec, count); |
bd2b5b12 PZ |
3672 | |
3673 | delta = (s64)(period - hwc->sample_period); | |
3674 | delta = (delta + 7) / 8; /* low pass filter */ | |
3675 | ||
3676 | sample_period = hwc->sample_period + delta; | |
3677 | ||
3678 | if (!sample_period) | |
3679 | sample_period = 1; | |
3680 | ||
bd2b5b12 | 3681 | hwc->sample_period = sample_period; |
abd50713 | 3682 | |
e7850595 | 3683 | if (local64_read(&hwc->period_left) > 8*sample_period) { |
f39d47ff SE |
3684 | if (disable) |
3685 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3686 | ||
e7850595 | 3687 | local64_set(&hwc->period_left, 0); |
f39d47ff SE |
3688 | |
3689 | if (disable) | |
3690 | event->pmu->start(event, PERF_EF_RELOAD); | |
abd50713 | 3691 | } |
bd2b5b12 PZ |
3692 | } |
3693 | ||
e050e3f0 SE |
3694 | /* |
3695 | * combine freq adjustment with unthrottling to avoid two passes over the | |
3696 | * events. At the same time, make sure, having freq events does not change | |
3697 | * the rate of unthrottling as that would introduce bias. | |
3698 | */ | |
3699 | static void perf_adjust_freq_unthr_context(struct perf_event_context *ctx, | |
3700 | int needs_unthr) | |
60db5e09 | 3701 | { |
cdd6c482 IM |
3702 | struct perf_event *event; |
3703 | struct hw_perf_event *hwc; | |
e050e3f0 | 3704 | u64 now, period = TICK_NSEC; |
abd50713 | 3705 | s64 delta; |
60db5e09 | 3706 | |
e050e3f0 SE |
3707 | /* |
3708 | * only need to iterate over all events iff: | |
3709 | * - context have events in frequency mode (needs freq adjust) | |
3710 | * - there are events to unthrottle on this cpu | |
3711 | */ | |
3712 | if (!(ctx->nr_freq || needs_unthr)) | |
0f5a2601 PZ |
3713 | return; |
3714 | ||
e050e3f0 | 3715 | raw_spin_lock(&ctx->lock); |
f39d47ff | 3716 | perf_pmu_disable(ctx->pmu); |
e050e3f0 | 3717 | |
03541f8b | 3718 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { |
cdd6c482 | 3719 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
60db5e09 PZ |
3720 | continue; |
3721 | ||
5632ab12 | 3722 | if (!event_filter_match(event)) |
5d27c23d PZ |
3723 | continue; |
3724 | ||
44377277 AS |
3725 | perf_pmu_disable(event->pmu); |
3726 | ||
cdd6c482 | 3727 | hwc = &event->hw; |
6a24ed6c | 3728 | |
ae23bff1 | 3729 | if (hwc->interrupts == MAX_INTERRUPTS) { |
e050e3f0 | 3730 | hwc->interrupts = 0; |
cdd6c482 | 3731 | perf_log_throttle(event, 1); |
a4eaf7f1 | 3732 | event->pmu->start(event, 0); |
a78ac325 PZ |
3733 | } |
3734 | ||
cdd6c482 | 3735 | if (!event->attr.freq || !event->attr.sample_freq) |
44377277 | 3736 | goto next; |
60db5e09 | 3737 | |
e050e3f0 SE |
3738 | /* |
3739 | * stop the event and update event->count | |
3740 | */ | |
3741 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3742 | ||
e7850595 | 3743 | now = local64_read(&event->count); |
abd50713 PZ |
3744 | delta = now - hwc->freq_count_stamp; |
3745 | hwc->freq_count_stamp = now; | |
60db5e09 | 3746 | |
e050e3f0 SE |
3747 | /* |
3748 | * restart the event | |
3749 | * reload only if value has changed | |
f39d47ff SE |
3750 | * we have stopped the event so tell that |
3751 | * to perf_adjust_period() to avoid stopping it | |
3752 | * twice. | |
e050e3f0 | 3753 | */ |
abd50713 | 3754 | if (delta > 0) |
f39d47ff | 3755 | perf_adjust_period(event, period, delta, false); |
e050e3f0 SE |
3756 | |
3757 | event->pmu->start(event, delta > 0 ? PERF_EF_RELOAD : 0); | |
44377277 AS |
3758 | next: |
3759 | perf_pmu_enable(event->pmu); | |
60db5e09 | 3760 | } |
e050e3f0 | 3761 | |
f39d47ff | 3762 | perf_pmu_enable(ctx->pmu); |
e050e3f0 | 3763 | raw_spin_unlock(&ctx->lock); |
60db5e09 PZ |
3764 | } |
3765 | ||
235c7fc7 | 3766 | /* |
8703a7cf | 3767 | * Move @event to the tail of the @ctx's elegible events. |
235c7fc7 | 3768 | */ |
8703a7cf | 3769 | static void rotate_ctx(struct perf_event_context *ctx, struct perf_event *event) |
0793a61d | 3770 | { |
dddd3379 TG |
3771 | /* |
3772 | * Rotate the first entry last of non-pinned groups. Rotation might be | |
3773 | * disabled by the inheritance code. | |
3774 | */ | |
8703a7cf PZ |
3775 | if (ctx->rotate_disable) |
3776 | return; | |
8e1a2031 | 3777 | |
8703a7cf PZ |
3778 | perf_event_groups_delete(&ctx->flexible_groups, event); |
3779 | perf_event_groups_insert(&ctx->flexible_groups, event); | |
235c7fc7 IM |
3780 | } |
3781 | ||
7fa343b7 | 3782 | /* pick an event from the flexible_groups to rotate */ |
8d5bce0c | 3783 | static inline struct perf_event * |
7fa343b7 | 3784 | ctx_event_to_rotate(struct perf_event_context *ctx) |
235c7fc7 | 3785 | { |
7fa343b7 SL |
3786 | struct perf_event *event; |
3787 | ||
3788 | /* pick the first active flexible event */ | |
3789 | event = list_first_entry_or_null(&ctx->flexible_active, | |
3790 | struct perf_event, active_list); | |
3791 | ||
3792 | /* if no active flexible event, pick the first event */ | |
3793 | if (!event) { | |
3794 | event = rb_entry_safe(rb_first(&ctx->flexible_groups.tree), | |
3795 | typeof(*event), group_node); | |
3796 | } | |
3797 | ||
3798 | return event; | |
8d5bce0c PZ |
3799 | } |
3800 | ||
3801 | static bool perf_rotate_context(struct perf_cpu_context *cpuctx) | |
3802 | { | |
3803 | struct perf_event *cpu_event = NULL, *task_event = NULL; | |
fd7d5517 IR |
3804 | struct perf_event_context *task_ctx = NULL; |
3805 | int cpu_rotate, task_rotate; | |
8d5bce0c PZ |
3806 | |
3807 | /* | |
3808 | * Since we run this from IRQ context, nobody can install new | |
3809 | * events, thus the event count values are stable. | |
3810 | */ | |
7fc23a53 | 3811 | |
fd7d5517 IR |
3812 | cpu_rotate = cpuctx->ctx.rotate_necessary; |
3813 | task_ctx = cpuctx->task_ctx; | |
3814 | task_rotate = task_ctx ? task_ctx->rotate_necessary : 0; | |
9717e6cd | 3815 | |
8d5bce0c PZ |
3816 | if (!(cpu_rotate || task_rotate)) |
3817 | return false; | |
0f5a2601 | 3818 | |
facc4307 | 3819 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
1b9a644f | 3820 | perf_pmu_disable(cpuctx->ctx.pmu); |
60db5e09 | 3821 | |
8d5bce0c | 3822 | if (task_rotate) |
7fa343b7 | 3823 | task_event = ctx_event_to_rotate(task_ctx); |
8d5bce0c | 3824 | if (cpu_rotate) |
7fa343b7 | 3825 | cpu_event = ctx_event_to_rotate(&cpuctx->ctx); |
8703a7cf | 3826 | |
8d5bce0c PZ |
3827 | /* |
3828 | * As per the order given at ctx_resched() first 'pop' task flexible | |
3829 | * and then, if needed CPU flexible. | |
3830 | */ | |
fd7d5517 IR |
3831 | if (task_event || (task_ctx && cpu_event)) |
3832 | ctx_sched_out(task_ctx, cpuctx, EVENT_FLEXIBLE); | |
8d5bce0c PZ |
3833 | if (cpu_event) |
3834 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
0793a61d | 3835 | |
8d5bce0c | 3836 | if (task_event) |
fd7d5517 | 3837 | rotate_ctx(task_ctx, task_event); |
8d5bce0c PZ |
3838 | if (cpu_event) |
3839 | rotate_ctx(&cpuctx->ctx, cpu_event); | |
235c7fc7 | 3840 | |
fd7d5517 | 3841 | perf_event_sched_in(cpuctx, task_ctx, current); |
235c7fc7 | 3842 | |
0f5a2601 PZ |
3843 | perf_pmu_enable(cpuctx->ctx.pmu); |
3844 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
9e630205 | 3845 | |
8d5bce0c | 3846 | return true; |
e9d2b064 PZ |
3847 | } |
3848 | ||
3849 | void perf_event_task_tick(void) | |
3850 | { | |
2fde4f94 MR |
3851 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
3852 | struct perf_event_context *ctx, *tmp; | |
e050e3f0 | 3853 | int throttled; |
b5ab4cd5 | 3854 | |
16444645 | 3855 | lockdep_assert_irqs_disabled(); |
e9d2b064 | 3856 | |
e050e3f0 SE |
3857 | __this_cpu_inc(perf_throttled_seq); |
3858 | throttled = __this_cpu_xchg(perf_throttled_count, 0); | |
555e0c1e | 3859 | tick_dep_clear_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
e050e3f0 | 3860 | |
2fde4f94 | 3861 | list_for_each_entry_safe(ctx, tmp, head, active_ctx_list) |
e050e3f0 | 3862 | perf_adjust_freq_unthr_context(ctx, throttled); |
0793a61d TG |
3863 | } |
3864 | ||
889ff015 FW |
3865 | static int event_enable_on_exec(struct perf_event *event, |
3866 | struct perf_event_context *ctx) | |
3867 | { | |
3868 | if (!event->attr.enable_on_exec) | |
3869 | return 0; | |
3870 | ||
3871 | event->attr.enable_on_exec = 0; | |
3872 | if (event->state >= PERF_EVENT_STATE_INACTIVE) | |
3873 | return 0; | |
3874 | ||
0d3d73aa | 3875 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
889ff015 FW |
3876 | |
3877 | return 1; | |
3878 | } | |
3879 | ||
57e7986e | 3880 | /* |
cdd6c482 | 3881 | * Enable all of a task's events that have been marked enable-on-exec. |
57e7986e PM |
3882 | * This expects task == current. |
3883 | */ | |
c1274499 | 3884 | static void perf_event_enable_on_exec(int ctxn) |
57e7986e | 3885 | { |
c1274499 | 3886 | struct perf_event_context *ctx, *clone_ctx = NULL; |
487f05e1 | 3887 | enum event_type_t event_type = 0; |
3e349507 | 3888 | struct perf_cpu_context *cpuctx; |
cdd6c482 | 3889 | struct perf_event *event; |
57e7986e PM |
3890 | unsigned long flags; |
3891 | int enabled = 0; | |
3892 | ||
3893 | local_irq_save(flags); | |
c1274499 | 3894 | ctx = current->perf_event_ctxp[ctxn]; |
cdd6c482 | 3895 | if (!ctx || !ctx->nr_events) |
57e7986e PM |
3896 | goto out; |
3897 | ||
3e349507 PZ |
3898 | cpuctx = __get_cpu_context(ctx); |
3899 | perf_ctx_lock(cpuctx, ctx); | |
7fce2509 | 3900 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
487f05e1 | 3901 | list_for_each_entry(event, &ctx->event_list, event_entry) { |
3e349507 | 3902 | enabled |= event_enable_on_exec(event, ctx); |
487f05e1 AS |
3903 | event_type |= get_event_type(event); |
3904 | } | |
57e7986e PM |
3905 | |
3906 | /* | |
3e349507 | 3907 | * Unclone and reschedule this context if we enabled any event. |
57e7986e | 3908 | */ |
3e349507 | 3909 | if (enabled) { |
211de6eb | 3910 | clone_ctx = unclone_ctx(ctx); |
487f05e1 | 3911 | ctx_resched(cpuctx, ctx, event_type); |
7bbba0eb PZ |
3912 | } else { |
3913 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
3e349507 PZ |
3914 | } |
3915 | perf_ctx_unlock(cpuctx, ctx); | |
57e7986e | 3916 | |
9ed6060d | 3917 | out: |
57e7986e | 3918 | local_irq_restore(flags); |
211de6eb PZ |
3919 | |
3920 | if (clone_ctx) | |
3921 | put_ctx(clone_ctx); | |
57e7986e PM |
3922 | } |
3923 | ||
0492d4c5 PZ |
3924 | struct perf_read_data { |
3925 | struct perf_event *event; | |
3926 | bool group; | |
7d88962e | 3927 | int ret; |
0492d4c5 PZ |
3928 | }; |
3929 | ||
451d24d1 | 3930 | static int __perf_event_read_cpu(struct perf_event *event, int event_cpu) |
d6a2f903 | 3931 | { |
d6a2f903 DCC |
3932 | u16 local_pkg, event_pkg; |
3933 | ||
3934 | if (event->group_caps & PERF_EV_CAP_READ_ACTIVE_PKG) { | |
451d24d1 PZ |
3935 | int local_cpu = smp_processor_id(); |
3936 | ||
3937 | event_pkg = topology_physical_package_id(event_cpu); | |
3938 | local_pkg = topology_physical_package_id(local_cpu); | |
d6a2f903 DCC |
3939 | |
3940 | if (event_pkg == local_pkg) | |
3941 | return local_cpu; | |
3942 | } | |
3943 | ||
3944 | return event_cpu; | |
3945 | } | |
3946 | ||
0793a61d | 3947 | /* |
cdd6c482 | 3948 | * Cross CPU call to read the hardware event |
0793a61d | 3949 | */ |
cdd6c482 | 3950 | static void __perf_event_read(void *info) |
0793a61d | 3951 | { |
0492d4c5 PZ |
3952 | struct perf_read_data *data = info; |
3953 | struct perf_event *sub, *event = data->event; | |
cdd6c482 | 3954 | struct perf_event_context *ctx = event->ctx; |
108b02cf | 3955 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
4a00c16e | 3956 | struct pmu *pmu = event->pmu; |
621a01ea | 3957 | |
e1ac3614 PM |
3958 | /* |
3959 | * If this is a task context, we need to check whether it is | |
3960 | * the current task context of this cpu. If not it has been | |
3961 | * scheduled out before the smp call arrived. In that case | |
cdd6c482 IM |
3962 | * event->count would have been updated to a recent sample |
3963 | * when the event was scheduled out. | |
e1ac3614 PM |
3964 | */ |
3965 | if (ctx->task && cpuctx->task_ctx != ctx) | |
3966 | return; | |
3967 | ||
e625cce1 | 3968 | raw_spin_lock(&ctx->lock); |
0c1cbc18 | 3969 | if (ctx->is_active & EVENT_TIME) { |
542e72fc | 3970 | update_context_time(ctx); |
e5d1367f SE |
3971 | update_cgrp_time_from_event(event); |
3972 | } | |
0492d4c5 | 3973 | |
0d3d73aa PZ |
3974 | perf_event_update_time(event); |
3975 | if (data->group) | |
3976 | perf_event_update_sibling_time(event); | |
0c1cbc18 | 3977 | |
4a00c16e SB |
3978 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
3979 | goto unlock; | |
0492d4c5 | 3980 | |
4a00c16e SB |
3981 | if (!data->group) { |
3982 | pmu->read(event); | |
3983 | data->ret = 0; | |
0492d4c5 | 3984 | goto unlock; |
4a00c16e SB |
3985 | } |
3986 | ||
3987 | pmu->start_txn(pmu, PERF_PMU_TXN_READ); | |
3988 | ||
3989 | pmu->read(event); | |
0492d4c5 | 3990 | |
edb39592 | 3991 | for_each_sibling_event(sub, event) { |
4a00c16e SB |
3992 | if (sub->state == PERF_EVENT_STATE_ACTIVE) { |
3993 | /* | |
3994 | * Use sibling's PMU rather than @event's since | |
3995 | * sibling could be on different (eg: software) PMU. | |
3996 | */ | |
0492d4c5 | 3997 | sub->pmu->read(sub); |
4a00c16e | 3998 | } |
0492d4c5 | 3999 | } |
4a00c16e SB |
4000 | |
4001 | data->ret = pmu->commit_txn(pmu); | |
0492d4c5 PZ |
4002 | |
4003 | unlock: | |
e625cce1 | 4004 | raw_spin_unlock(&ctx->lock); |
0793a61d TG |
4005 | } |
4006 | ||
b5e58793 PZ |
4007 | static inline u64 perf_event_count(struct perf_event *event) |
4008 | { | |
c39a0e2c | 4009 | return local64_read(&event->count) + atomic64_read(&event->child_count); |
b5e58793 PZ |
4010 | } |
4011 | ||
ffe8690c KX |
4012 | /* |
4013 | * NMI-safe method to read a local event, that is an event that | |
4014 | * is: | |
4015 | * - either for the current task, or for this CPU | |
4016 | * - does not have inherit set, for inherited task events | |
4017 | * will not be local and we cannot read them atomically | |
4018 | * - must not have a pmu::count method | |
4019 | */ | |
7d9285e8 YS |
4020 | int perf_event_read_local(struct perf_event *event, u64 *value, |
4021 | u64 *enabled, u64 *running) | |
ffe8690c KX |
4022 | { |
4023 | unsigned long flags; | |
f91840a3 | 4024 | int ret = 0; |
ffe8690c KX |
4025 | |
4026 | /* | |
4027 | * Disabling interrupts avoids all counter scheduling (context | |
4028 | * switches, timer based rotation and IPIs). | |
4029 | */ | |
4030 | local_irq_save(flags); | |
4031 | ||
ffe8690c KX |
4032 | /* |
4033 | * It must not be an event with inherit set, we cannot read | |
4034 | * all child counters from atomic context. | |
4035 | */ | |
f91840a3 AS |
4036 | if (event->attr.inherit) { |
4037 | ret = -EOPNOTSUPP; | |
4038 | goto out; | |
4039 | } | |
ffe8690c | 4040 | |
f91840a3 AS |
4041 | /* If this is a per-task event, it must be for current */ |
4042 | if ((event->attach_state & PERF_ATTACH_TASK) && | |
4043 | event->hw.target != current) { | |
4044 | ret = -EINVAL; | |
4045 | goto out; | |
4046 | } | |
4047 | ||
4048 | /* If this is a per-CPU event, it must be for this CPU */ | |
4049 | if (!(event->attach_state & PERF_ATTACH_TASK) && | |
4050 | event->cpu != smp_processor_id()) { | |
4051 | ret = -EINVAL; | |
4052 | goto out; | |
4053 | } | |
ffe8690c | 4054 | |
befb1b3c RC |
4055 | /* If this is a pinned event it must be running on this CPU */ |
4056 | if (event->attr.pinned && event->oncpu != smp_processor_id()) { | |
4057 | ret = -EBUSY; | |
4058 | goto out; | |
4059 | } | |
4060 | ||
ffe8690c KX |
4061 | /* |
4062 | * If the event is currently on this CPU, its either a per-task event, | |
4063 | * or local to this CPU. Furthermore it means its ACTIVE (otherwise | |
4064 | * oncpu == -1). | |
4065 | */ | |
4066 | if (event->oncpu == smp_processor_id()) | |
4067 | event->pmu->read(event); | |
4068 | ||
f91840a3 | 4069 | *value = local64_read(&event->count); |
0d3d73aa PZ |
4070 | if (enabled || running) { |
4071 | u64 now = event->shadow_ctx_time + perf_clock(); | |
4072 | u64 __enabled, __running; | |
4073 | ||
4074 | __perf_update_times(event, now, &__enabled, &__running); | |
4075 | if (enabled) | |
4076 | *enabled = __enabled; | |
4077 | if (running) | |
4078 | *running = __running; | |
4079 | } | |
f91840a3 | 4080 | out: |
ffe8690c KX |
4081 | local_irq_restore(flags); |
4082 | ||
f91840a3 | 4083 | return ret; |
ffe8690c KX |
4084 | } |
4085 | ||
7d88962e | 4086 | static int perf_event_read(struct perf_event *event, bool group) |
0793a61d | 4087 | { |
0c1cbc18 | 4088 | enum perf_event_state state = READ_ONCE(event->state); |
451d24d1 | 4089 | int event_cpu, ret = 0; |
7d88962e | 4090 | |
0793a61d | 4091 | /* |
cdd6c482 IM |
4092 | * If event is enabled and currently active on a CPU, update the |
4093 | * value in the event structure: | |
0793a61d | 4094 | */ |
0c1cbc18 PZ |
4095 | again: |
4096 | if (state == PERF_EVENT_STATE_ACTIVE) { | |
4097 | struct perf_read_data data; | |
4098 | ||
4099 | /* | |
4100 | * Orders the ->state and ->oncpu loads such that if we see | |
4101 | * ACTIVE we must also see the right ->oncpu. | |
4102 | * | |
4103 | * Matches the smp_wmb() from event_sched_in(). | |
4104 | */ | |
4105 | smp_rmb(); | |
d6a2f903 | 4106 | |
451d24d1 PZ |
4107 | event_cpu = READ_ONCE(event->oncpu); |
4108 | if ((unsigned)event_cpu >= nr_cpu_ids) | |
4109 | return 0; | |
4110 | ||
0c1cbc18 PZ |
4111 | data = (struct perf_read_data){ |
4112 | .event = event, | |
4113 | .group = group, | |
4114 | .ret = 0, | |
4115 | }; | |
4116 | ||
451d24d1 PZ |
4117 | preempt_disable(); |
4118 | event_cpu = __perf_event_read_cpu(event, event_cpu); | |
d6a2f903 | 4119 | |
58763148 PZ |
4120 | /* |
4121 | * Purposely ignore the smp_call_function_single() return | |
4122 | * value. | |
4123 | * | |
451d24d1 | 4124 | * If event_cpu isn't a valid CPU it means the event got |
58763148 PZ |
4125 | * scheduled out and that will have updated the event count. |
4126 | * | |
4127 | * Therefore, either way, we'll have an up-to-date event count | |
4128 | * after this. | |
4129 | */ | |
451d24d1 PZ |
4130 | (void)smp_call_function_single(event_cpu, __perf_event_read, &data, 1); |
4131 | preempt_enable(); | |
58763148 | 4132 | ret = data.ret; |
0c1cbc18 PZ |
4133 | |
4134 | } else if (state == PERF_EVENT_STATE_INACTIVE) { | |
2b8988c9 PZ |
4135 | struct perf_event_context *ctx = event->ctx; |
4136 | unsigned long flags; | |
4137 | ||
e625cce1 | 4138 | raw_spin_lock_irqsave(&ctx->lock, flags); |
0c1cbc18 PZ |
4139 | state = event->state; |
4140 | if (state != PERF_EVENT_STATE_INACTIVE) { | |
4141 | raw_spin_unlock_irqrestore(&ctx->lock, flags); | |
4142 | goto again; | |
4143 | } | |
4144 | ||
c530ccd9 | 4145 | /* |
0c1cbc18 PZ |
4146 | * May read while context is not active (e.g., thread is |
4147 | * blocked), in that case we cannot update context time | |
c530ccd9 | 4148 | */ |
0c1cbc18 | 4149 | if (ctx->is_active & EVENT_TIME) { |
c530ccd9 | 4150 | update_context_time(ctx); |
e5d1367f SE |
4151 | update_cgrp_time_from_event(event); |
4152 | } | |
0c1cbc18 | 4153 | |
0d3d73aa | 4154 | perf_event_update_time(event); |
0492d4c5 | 4155 | if (group) |
0d3d73aa | 4156 | perf_event_update_sibling_time(event); |
e625cce1 | 4157 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
0793a61d | 4158 | } |
7d88962e SB |
4159 | |
4160 | return ret; | |
0793a61d TG |
4161 | } |
4162 | ||
a63eaf34 | 4163 | /* |
cdd6c482 | 4164 | * Initialize the perf_event context in a task_struct: |
a63eaf34 | 4165 | */ |
eb184479 | 4166 | static void __perf_event_init_context(struct perf_event_context *ctx) |
a63eaf34 | 4167 | { |
e625cce1 | 4168 | raw_spin_lock_init(&ctx->lock); |
a63eaf34 | 4169 | mutex_init(&ctx->mutex); |
2fde4f94 | 4170 | INIT_LIST_HEAD(&ctx->active_ctx_list); |
8e1a2031 AB |
4171 | perf_event_groups_init(&ctx->pinned_groups); |
4172 | perf_event_groups_init(&ctx->flexible_groups); | |
a63eaf34 | 4173 | INIT_LIST_HEAD(&ctx->event_list); |
6668128a PZ |
4174 | INIT_LIST_HEAD(&ctx->pinned_active); |
4175 | INIT_LIST_HEAD(&ctx->flexible_active); | |
8c94abbb | 4176 | refcount_set(&ctx->refcount, 1); |
eb184479 PZ |
4177 | } |
4178 | ||
4179 | static struct perf_event_context * | |
4180 | alloc_perf_context(struct pmu *pmu, struct task_struct *task) | |
4181 | { | |
4182 | struct perf_event_context *ctx; | |
4183 | ||
4184 | ctx = kzalloc(sizeof(struct perf_event_context), GFP_KERNEL); | |
4185 | if (!ctx) | |
4186 | return NULL; | |
4187 | ||
4188 | __perf_event_init_context(ctx); | |
7b3c92b8 MWO |
4189 | if (task) |
4190 | ctx->task = get_task_struct(task); | |
eb184479 PZ |
4191 | ctx->pmu = pmu; |
4192 | ||
4193 | return ctx; | |
a63eaf34 PM |
4194 | } |
4195 | ||
2ebd4ffb MH |
4196 | static struct task_struct * |
4197 | find_lively_task_by_vpid(pid_t vpid) | |
4198 | { | |
4199 | struct task_struct *task; | |
0793a61d TG |
4200 | |
4201 | rcu_read_lock(); | |
2ebd4ffb | 4202 | if (!vpid) |
0793a61d TG |
4203 | task = current; |
4204 | else | |
2ebd4ffb | 4205 | task = find_task_by_vpid(vpid); |
0793a61d TG |
4206 | if (task) |
4207 | get_task_struct(task); | |
4208 | rcu_read_unlock(); | |
4209 | ||
4210 | if (!task) | |
4211 | return ERR_PTR(-ESRCH); | |
4212 | ||
2ebd4ffb | 4213 | return task; |
2ebd4ffb MH |
4214 | } |
4215 | ||
fe4b04fa PZ |
4216 | /* |
4217 | * Returns a matching context with refcount and pincount. | |
4218 | */ | |
108b02cf | 4219 | static struct perf_event_context * |
4af57ef2 YZ |
4220 | find_get_context(struct pmu *pmu, struct task_struct *task, |
4221 | struct perf_event *event) | |
0793a61d | 4222 | { |
211de6eb | 4223 | struct perf_event_context *ctx, *clone_ctx = NULL; |
22a4f650 | 4224 | struct perf_cpu_context *cpuctx; |
4af57ef2 | 4225 | void *task_ctx_data = NULL; |
25346b93 | 4226 | unsigned long flags; |
8dc85d54 | 4227 | int ctxn, err; |
4af57ef2 | 4228 | int cpu = event->cpu; |
0793a61d | 4229 | |
22a4ec72 | 4230 | if (!task) { |
cdd6c482 | 4231 | /* Must be root to operate on a CPU event: */ |
0764771d | 4232 | if (perf_paranoid_cpu() && !capable(CAP_SYS_ADMIN)) |
0793a61d TG |
4233 | return ERR_PTR(-EACCES); |
4234 | ||
108b02cf | 4235 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); |
0793a61d | 4236 | ctx = &cpuctx->ctx; |
c93f7669 | 4237 | get_ctx(ctx); |
fe4b04fa | 4238 | ++ctx->pin_count; |
0793a61d | 4239 | |
0793a61d TG |
4240 | return ctx; |
4241 | } | |
4242 | ||
8dc85d54 PZ |
4243 | err = -EINVAL; |
4244 | ctxn = pmu->task_ctx_nr; | |
4245 | if (ctxn < 0) | |
4246 | goto errout; | |
4247 | ||
4af57ef2 YZ |
4248 | if (event->attach_state & PERF_ATTACH_TASK_DATA) { |
4249 | task_ctx_data = kzalloc(pmu->task_ctx_size, GFP_KERNEL); | |
4250 | if (!task_ctx_data) { | |
4251 | err = -ENOMEM; | |
4252 | goto errout; | |
4253 | } | |
4254 | } | |
4255 | ||
9ed6060d | 4256 | retry: |
8dc85d54 | 4257 | ctx = perf_lock_task_context(task, ctxn, &flags); |
c93f7669 | 4258 | if (ctx) { |
211de6eb | 4259 | clone_ctx = unclone_ctx(ctx); |
fe4b04fa | 4260 | ++ctx->pin_count; |
4af57ef2 YZ |
4261 | |
4262 | if (task_ctx_data && !ctx->task_ctx_data) { | |
4263 | ctx->task_ctx_data = task_ctx_data; | |
4264 | task_ctx_data = NULL; | |
4265 | } | |
e625cce1 | 4266 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
211de6eb PZ |
4267 | |
4268 | if (clone_ctx) | |
4269 | put_ctx(clone_ctx); | |
9137fb28 | 4270 | } else { |
eb184479 | 4271 | ctx = alloc_perf_context(pmu, task); |
c93f7669 PM |
4272 | err = -ENOMEM; |
4273 | if (!ctx) | |
4274 | goto errout; | |
eb184479 | 4275 | |
4af57ef2 YZ |
4276 | if (task_ctx_data) { |
4277 | ctx->task_ctx_data = task_ctx_data; | |
4278 | task_ctx_data = NULL; | |
4279 | } | |
4280 | ||
dbe08d82 ON |
4281 | err = 0; |
4282 | mutex_lock(&task->perf_event_mutex); | |
4283 | /* | |
4284 | * If it has already passed perf_event_exit_task(). | |
4285 | * we must see PF_EXITING, it takes this mutex too. | |
4286 | */ | |
4287 | if (task->flags & PF_EXITING) | |
4288 | err = -ESRCH; | |
4289 | else if (task->perf_event_ctxp[ctxn]) | |
4290 | err = -EAGAIN; | |
fe4b04fa | 4291 | else { |
9137fb28 | 4292 | get_ctx(ctx); |
fe4b04fa | 4293 | ++ctx->pin_count; |
dbe08d82 | 4294 | rcu_assign_pointer(task->perf_event_ctxp[ctxn], ctx); |
fe4b04fa | 4295 | } |
dbe08d82 ON |
4296 | mutex_unlock(&task->perf_event_mutex); |
4297 | ||
4298 | if (unlikely(err)) { | |
9137fb28 | 4299 | put_ctx(ctx); |
dbe08d82 ON |
4300 | |
4301 | if (err == -EAGAIN) | |
4302 | goto retry; | |
4303 | goto errout; | |
a63eaf34 PM |
4304 | } |
4305 | } | |
4306 | ||
4af57ef2 | 4307 | kfree(task_ctx_data); |
0793a61d | 4308 | return ctx; |
c93f7669 | 4309 | |
9ed6060d | 4310 | errout: |
4af57ef2 | 4311 | kfree(task_ctx_data); |
c93f7669 | 4312 | return ERR_PTR(err); |
0793a61d TG |
4313 | } |
4314 | ||
6fb2915d | 4315 | static void perf_event_free_filter(struct perf_event *event); |
2541517c | 4316 | static void perf_event_free_bpf_prog(struct perf_event *event); |
6fb2915d | 4317 | |
cdd6c482 | 4318 | static void free_event_rcu(struct rcu_head *head) |
592903cd | 4319 | { |
cdd6c482 | 4320 | struct perf_event *event; |
592903cd | 4321 | |
cdd6c482 IM |
4322 | event = container_of(head, struct perf_event, rcu_head); |
4323 | if (event->ns) | |
4324 | put_pid_ns(event->ns); | |
6fb2915d | 4325 | perf_event_free_filter(event); |
cdd6c482 | 4326 | kfree(event); |
592903cd PZ |
4327 | } |
4328 | ||
b69cf536 PZ |
4329 | static void ring_buffer_attach(struct perf_event *event, |
4330 | struct ring_buffer *rb); | |
925d519a | 4331 | |
f2fb6bef KL |
4332 | static void detach_sb_event(struct perf_event *event) |
4333 | { | |
4334 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
4335 | ||
4336 | raw_spin_lock(&pel->lock); | |
4337 | list_del_rcu(&event->sb_list); | |
4338 | raw_spin_unlock(&pel->lock); | |
4339 | } | |
4340 | ||
a4f144eb | 4341 | static bool is_sb_event(struct perf_event *event) |
f2fb6bef | 4342 | { |
a4f144eb DCC |
4343 | struct perf_event_attr *attr = &event->attr; |
4344 | ||
f2fb6bef | 4345 | if (event->parent) |
a4f144eb | 4346 | return false; |
f2fb6bef KL |
4347 | |
4348 | if (event->attach_state & PERF_ATTACH_TASK) | |
a4f144eb | 4349 | return false; |
f2fb6bef | 4350 | |
a4f144eb DCC |
4351 | if (attr->mmap || attr->mmap_data || attr->mmap2 || |
4352 | attr->comm || attr->comm_exec || | |
76193a94 | 4353 | attr->task || attr->ksymbol || |
21038f2b SL |
4354 | attr->context_switch || |
4355 | attr->bpf_event) | |
a4f144eb DCC |
4356 | return true; |
4357 | return false; | |
4358 | } | |
4359 | ||
4360 | static void unaccount_pmu_sb_event(struct perf_event *event) | |
4361 | { | |
4362 | if (is_sb_event(event)) | |
4363 | detach_sb_event(event); | |
f2fb6bef KL |
4364 | } |
4365 | ||
4beb31f3 | 4366 | static void unaccount_event_cpu(struct perf_event *event, int cpu) |
f1600952 | 4367 | { |
4beb31f3 FW |
4368 | if (event->parent) |
4369 | return; | |
4370 | ||
4beb31f3 FW |
4371 | if (is_cgroup_event(event)) |
4372 | atomic_dec(&per_cpu(perf_cgroup_events, cpu)); | |
4373 | } | |
925d519a | 4374 | |
555e0c1e FW |
4375 | #ifdef CONFIG_NO_HZ_FULL |
4376 | static DEFINE_SPINLOCK(nr_freq_lock); | |
4377 | #endif | |
4378 | ||
4379 | static void unaccount_freq_event_nohz(void) | |
4380 | { | |
4381 | #ifdef CONFIG_NO_HZ_FULL | |
4382 | spin_lock(&nr_freq_lock); | |
4383 | if (atomic_dec_and_test(&nr_freq_events)) | |
4384 | tick_nohz_dep_clear(TICK_DEP_BIT_PERF_EVENTS); | |
4385 | spin_unlock(&nr_freq_lock); | |
4386 | #endif | |
4387 | } | |
4388 | ||
4389 | static void unaccount_freq_event(void) | |
4390 | { | |
4391 | if (tick_nohz_full_enabled()) | |
4392 | unaccount_freq_event_nohz(); | |
4393 | else | |
4394 | atomic_dec(&nr_freq_events); | |
4395 | } | |
4396 | ||
4beb31f3 FW |
4397 | static void unaccount_event(struct perf_event *event) |
4398 | { | |
25432ae9 PZ |
4399 | bool dec = false; |
4400 | ||
4beb31f3 FW |
4401 | if (event->parent) |
4402 | return; | |
4403 | ||
4404 | if (event->attach_state & PERF_ATTACH_TASK) | |
25432ae9 | 4405 | dec = true; |
4beb31f3 FW |
4406 | if (event->attr.mmap || event->attr.mmap_data) |
4407 | atomic_dec(&nr_mmap_events); | |
4408 | if (event->attr.comm) | |
4409 | atomic_dec(&nr_comm_events); | |
e4222673 HB |
4410 | if (event->attr.namespaces) |
4411 | atomic_dec(&nr_namespaces_events); | |
4beb31f3 FW |
4412 | if (event->attr.task) |
4413 | atomic_dec(&nr_task_events); | |
948b26b6 | 4414 | if (event->attr.freq) |
555e0c1e | 4415 | unaccount_freq_event(); |
45ac1403 | 4416 | if (event->attr.context_switch) { |
25432ae9 | 4417 | dec = true; |
45ac1403 AH |
4418 | atomic_dec(&nr_switch_events); |
4419 | } | |
4beb31f3 | 4420 | if (is_cgroup_event(event)) |
25432ae9 | 4421 | dec = true; |
4beb31f3 | 4422 | if (has_branch_stack(event)) |
25432ae9 | 4423 | dec = true; |
76193a94 SL |
4424 | if (event->attr.ksymbol) |
4425 | atomic_dec(&nr_ksymbol_events); | |
6ee52e2a SL |
4426 | if (event->attr.bpf_event) |
4427 | atomic_dec(&nr_bpf_events); | |
25432ae9 | 4428 | |
9107c89e PZ |
4429 | if (dec) { |
4430 | if (!atomic_add_unless(&perf_sched_count, -1, 1)) | |
4431 | schedule_delayed_work(&perf_sched_work, HZ); | |
4432 | } | |
4beb31f3 FW |
4433 | |
4434 | unaccount_event_cpu(event, event->cpu); | |
f2fb6bef KL |
4435 | |
4436 | unaccount_pmu_sb_event(event); | |
4beb31f3 | 4437 | } |
925d519a | 4438 | |
9107c89e PZ |
4439 | static void perf_sched_delayed(struct work_struct *work) |
4440 | { | |
4441 | mutex_lock(&perf_sched_mutex); | |
4442 | if (atomic_dec_and_test(&perf_sched_count)) | |
4443 | static_branch_disable(&perf_sched_events); | |
4444 | mutex_unlock(&perf_sched_mutex); | |
4445 | } | |
4446 | ||
bed5b25a AS |
4447 | /* |
4448 | * The following implement mutual exclusion of events on "exclusive" pmus | |
4449 | * (PERF_PMU_CAP_EXCLUSIVE). Such pmus can only have one event scheduled | |
4450 | * at a time, so we disallow creating events that might conflict, namely: | |
4451 | * | |
4452 | * 1) cpu-wide events in the presence of per-task events, | |
4453 | * 2) per-task events in the presence of cpu-wide events, | |
4454 | * 3) two matching events on the same context. | |
4455 | * | |
4456 | * The former two cases are handled in the allocation path (perf_event_alloc(), | |
a0733e69 | 4457 | * _free_event()), the latter -- before the first perf_install_in_context(). |
bed5b25a AS |
4458 | */ |
4459 | static int exclusive_event_init(struct perf_event *event) | |
4460 | { | |
4461 | struct pmu *pmu = event->pmu; | |
4462 | ||
8a58ddae | 4463 | if (!is_exclusive_pmu(pmu)) |
bed5b25a AS |
4464 | return 0; |
4465 | ||
4466 | /* | |
4467 | * Prevent co-existence of per-task and cpu-wide events on the | |
4468 | * same exclusive pmu. | |
4469 | * | |
4470 | * Negative pmu::exclusive_cnt means there are cpu-wide | |
4471 | * events on this "exclusive" pmu, positive means there are | |
4472 | * per-task events. | |
4473 | * | |
4474 | * Since this is called in perf_event_alloc() path, event::ctx | |
4475 | * doesn't exist yet; it is, however, safe to use PERF_ATTACH_TASK | |
4476 | * to mean "per-task event", because unlike other attach states it | |
4477 | * never gets cleared. | |
4478 | */ | |
4479 | if (event->attach_state & PERF_ATTACH_TASK) { | |
4480 | if (!atomic_inc_unless_negative(&pmu->exclusive_cnt)) | |
4481 | return -EBUSY; | |
4482 | } else { | |
4483 | if (!atomic_dec_unless_positive(&pmu->exclusive_cnt)) | |
4484 | return -EBUSY; | |
4485 | } | |
4486 | ||
4487 | return 0; | |
4488 | } | |
4489 | ||
4490 | static void exclusive_event_destroy(struct perf_event *event) | |
4491 | { | |
4492 | struct pmu *pmu = event->pmu; | |
4493 | ||
8a58ddae | 4494 | if (!is_exclusive_pmu(pmu)) |
bed5b25a AS |
4495 | return; |
4496 | ||
4497 | /* see comment in exclusive_event_init() */ | |
4498 | if (event->attach_state & PERF_ATTACH_TASK) | |
4499 | atomic_dec(&pmu->exclusive_cnt); | |
4500 | else | |
4501 | atomic_inc(&pmu->exclusive_cnt); | |
4502 | } | |
4503 | ||
4504 | static bool exclusive_event_match(struct perf_event *e1, struct perf_event *e2) | |
4505 | { | |
3bf6215a | 4506 | if ((e1->pmu == e2->pmu) && |
bed5b25a AS |
4507 | (e1->cpu == e2->cpu || |
4508 | e1->cpu == -1 || | |
4509 | e2->cpu == -1)) | |
4510 | return true; | |
4511 | return false; | |
4512 | } | |
4513 | ||
bed5b25a AS |
4514 | static bool exclusive_event_installable(struct perf_event *event, |
4515 | struct perf_event_context *ctx) | |
4516 | { | |
4517 | struct perf_event *iter_event; | |
4518 | struct pmu *pmu = event->pmu; | |
4519 | ||
8a58ddae AS |
4520 | lockdep_assert_held(&ctx->mutex); |
4521 | ||
4522 | if (!is_exclusive_pmu(pmu)) | |
bed5b25a AS |
4523 | return true; |
4524 | ||
4525 | list_for_each_entry(iter_event, &ctx->event_list, event_entry) { | |
4526 | if (exclusive_event_match(iter_event, event)) | |
4527 | return false; | |
4528 | } | |
4529 | ||
4530 | return true; | |
4531 | } | |
4532 | ||
375637bc AS |
4533 | static void perf_addr_filters_splice(struct perf_event *event, |
4534 | struct list_head *head); | |
4535 | ||
683ede43 | 4536 | static void _free_event(struct perf_event *event) |
f1600952 | 4537 | { |
e360adbe | 4538 | irq_work_sync(&event->pending); |
925d519a | 4539 | |
4beb31f3 | 4540 | unaccount_event(event); |
9ee318a7 | 4541 | |
76369139 | 4542 | if (event->rb) { |
9bb5d40c PZ |
4543 | /* |
4544 | * Can happen when we close an event with re-directed output. | |
4545 | * | |
4546 | * Since we have a 0 refcount, perf_mmap_close() will skip | |
4547 | * over us; possibly making our ring_buffer_put() the last. | |
4548 | */ | |
4549 | mutex_lock(&event->mmap_mutex); | |
b69cf536 | 4550 | ring_buffer_attach(event, NULL); |
9bb5d40c | 4551 | mutex_unlock(&event->mmap_mutex); |
a4be7c27 PZ |
4552 | } |
4553 | ||
e5d1367f SE |
4554 | if (is_cgroup_event(event)) |
4555 | perf_detach_cgroup(event); | |
4556 | ||
a0733e69 PZ |
4557 | if (!event->parent) { |
4558 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) | |
4559 | put_callchain_buffers(); | |
4560 | } | |
4561 | ||
4562 | perf_event_free_bpf_prog(event); | |
375637bc | 4563 | perf_addr_filters_splice(event, NULL); |
c60f83b8 | 4564 | kfree(event->addr_filter_ranges); |
a0733e69 PZ |
4565 | |
4566 | if (event->destroy) | |
4567 | event->destroy(event); | |
4568 | ||
1cf8dfe8 PZ |
4569 | /* |
4570 | * Must be after ->destroy(), due to uprobe_perf_close() using | |
4571 | * hw.target. | |
4572 | */ | |
621b6d2e PB |
4573 | if (event->hw.target) |
4574 | put_task_struct(event->hw.target); | |
4575 | ||
1cf8dfe8 PZ |
4576 | /* |
4577 | * perf_event_free_task() relies on put_ctx() being 'last', in particular | |
4578 | * all task references must be cleaned up. | |
4579 | */ | |
4580 | if (event->ctx) | |
4581 | put_ctx(event->ctx); | |
4582 | ||
62a92c8f AS |
4583 | exclusive_event_destroy(event); |
4584 | module_put(event->pmu->module); | |
a0733e69 PZ |
4585 | |
4586 | call_rcu(&event->rcu_head, free_event_rcu); | |
f1600952 PZ |
4587 | } |
4588 | ||
683ede43 PZ |
4589 | /* |
4590 | * Used to free events which have a known refcount of 1, such as in error paths | |
4591 | * where the event isn't exposed yet and inherited events. | |
4592 | */ | |
4593 | static void free_event(struct perf_event *event) | |
0793a61d | 4594 | { |
683ede43 PZ |
4595 | if (WARN(atomic_long_cmpxchg(&event->refcount, 1, 0) != 1, |
4596 | "unexpected event refcount: %ld; ptr=%p\n", | |
4597 | atomic_long_read(&event->refcount), event)) { | |
4598 | /* leak to avoid use-after-free */ | |
4599 | return; | |
4600 | } | |
0793a61d | 4601 | |
683ede43 | 4602 | _free_event(event); |
0793a61d TG |
4603 | } |
4604 | ||
a66a3052 | 4605 | /* |
f8697762 | 4606 | * Remove user event from the owner task. |
a66a3052 | 4607 | */ |
f8697762 | 4608 | static void perf_remove_from_owner(struct perf_event *event) |
fb0459d7 | 4609 | { |
8882135b | 4610 | struct task_struct *owner; |
fb0459d7 | 4611 | |
8882135b | 4612 | rcu_read_lock(); |
8882135b | 4613 | /* |
f47c02c0 PZ |
4614 | * Matches the smp_store_release() in perf_event_exit_task(). If we |
4615 | * observe !owner it means the list deletion is complete and we can | |
4616 | * indeed free this event, otherwise we need to serialize on | |
8882135b PZ |
4617 | * owner->perf_event_mutex. |
4618 | */ | |
506458ef | 4619 | owner = READ_ONCE(event->owner); |
8882135b PZ |
4620 | if (owner) { |
4621 | /* | |
4622 | * Since delayed_put_task_struct() also drops the last | |
4623 | * task reference we can safely take a new reference | |
4624 | * while holding the rcu_read_lock(). | |
4625 | */ | |
4626 | get_task_struct(owner); | |
4627 | } | |
4628 | rcu_read_unlock(); | |
4629 | ||
4630 | if (owner) { | |
f63a8daa PZ |
4631 | /* |
4632 | * If we're here through perf_event_exit_task() we're already | |
4633 | * holding ctx->mutex which would be an inversion wrt. the | |
4634 | * normal lock order. | |
4635 | * | |
4636 | * However we can safely take this lock because its the child | |
4637 | * ctx->mutex. | |
4638 | */ | |
4639 | mutex_lock_nested(&owner->perf_event_mutex, SINGLE_DEPTH_NESTING); | |
4640 | ||
8882135b PZ |
4641 | /* |
4642 | * We have to re-check the event->owner field, if it is cleared | |
4643 | * we raced with perf_event_exit_task(), acquiring the mutex | |
4644 | * ensured they're done, and we can proceed with freeing the | |
4645 | * event. | |
4646 | */ | |
f47c02c0 | 4647 | if (event->owner) { |
8882135b | 4648 | list_del_init(&event->owner_entry); |
f47c02c0 PZ |
4649 | smp_store_release(&event->owner, NULL); |
4650 | } | |
8882135b PZ |
4651 | mutex_unlock(&owner->perf_event_mutex); |
4652 | put_task_struct(owner); | |
4653 | } | |
f8697762 JO |
4654 | } |
4655 | ||
f8697762 JO |
4656 | static void put_event(struct perf_event *event) |
4657 | { | |
f8697762 JO |
4658 | if (!atomic_long_dec_and_test(&event->refcount)) |
4659 | return; | |
4660 | ||
c6e5b732 PZ |
4661 | _free_event(event); |
4662 | } | |
4663 | ||
4664 | /* | |
4665 | * Kill an event dead; while event:refcount will preserve the event | |
4666 | * object, it will not preserve its functionality. Once the last 'user' | |
4667 | * gives up the object, we'll destroy the thing. | |
4668 | */ | |
4669 | int perf_event_release_kernel(struct perf_event *event) | |
4670 | { | |
a4f4bb6d | 4671 | struct perf_event_context *ctx = event->ctx; |
c6e5b732 | 4672 | struct perf_event *child, *tmp; |
82d94856 | 4673 | LIST_HEAD(free_list); |
c6e5b732 | 4674 | |
a4f4bb6d PZ |
4675 | /* |
4676 | * If we got here through err_file: fput(event_file); we will not have | |
4677 | * attached to a context yet. | |
4678 | */ | |
4679 | if (!ctx) { | |
4680 | WARN_ON_ONCE(event->attach_state & | |
4681 | (PERF_ATTACH_CONTEXT|PERF_ATTACH_GROUP)); | |
4682 | goto no_ctx; | |
4683 | } | |
4684 | ||
f8697762 JO |
4685 | if (!is_kernel_event(event)) |
4686 | perf_remove_from_owner(event); | |
8882135b | 4687 | |
5fa7c8ec | 4688 | ctx = perf_event_ctx_lock(event); |
a83fe28e | 4689 | WARN_ON_ONCE(ctx->parent_ctx); |
a69b0ca4 | 4690 | perf_remove_from_context(event, DETACH_GROUP); |
683ede43 | 4691 | |
a69b0ca4 | 4692 | raw_spin_lock_irq(&ctx->lock); |
683ede43 | 4693 | /* |
d8a8cfc7 | 4694 | * Mark this event as STATE_DEAD, there is no external reference to it |
a69b0ca4 | 4695 | * anymore. |
683ede43 | 4696 | * |
a69b0ca4 PZ |
4697 | * Anybody acquiring event->child_mutex after the below loop _must_ |
4698 | * also see this, most importantly inherit_event() which will avoid | |
4699 | * placing more children on the list. | |
683ede43 | 4700 | * |
c6e5b732 PZ |
4701 | * Thus this guarantees that we will in fact observe and kill _ALL_ |
4702 | * child events. | |
683ede43 | 4703 | */ |
a69b0ca4 PZ |
4704 | event->state = PERF_EVENT_STATE_DEAD; |
4705 | raw_spin_unlock_irq(&ctx->lock); | |
4706 | ||
4707 | perf_event_ctx_unlock(event, ctx); | |
683ede43 | 4708 | |
c6e5b732 PZ |
4709 | again: |
4710 | mutex_lock(&event->child_mutex); | |
4711 | list_for_each_entry(child, &event->child_list, child_list) { | |
a6fa941d | 4712 | |
c6e5b732 PZ |
4713 | /* |
4714 | * Cannot change, child events are not migrated, see the | |
4715 | * comment with perf_event_ctx_lock_nested(). | |
4716 | */ | |
506458ef | 4717 | ctx = READ_ONCE(child->ctx); |
c6e5b732 PZ |
4718 | /* |
4719 | * Since child_mutex nests inside ctx::mutex, we must jump | |
4720 | * through hoops. We start by grabbing a reference on the ctx. | |
4721 | * | |
4722 | * Since the event cannot get freed while we hold the | |
4723 | * child_mutex, the context must also exist and have a !0 | |
4724 | * reference count. | |
4725 | */ | |
4726 | get_ctx(ctx); | |
4727 | ||
4728 | /* | |
4729 | * Now that we have a ctx ref, we can drop child_mutex, and | |
4730 | * acquire ctx::mutex without fear of it going away. Then we | |
4731 | * can re-acquire child_mutex. | |
4732 | */ | |
4733 | mutex_unlock(&event->child_mutex); | |
4734 | mutex_lock(&ctx->mutex); | |
4735 | mutex_lock(&event->child_mutex); | |
4736 | ||
4737 | /* | |
4738 | * Now that we hold ctx::mutex and child_mutex, revalidate our | |
4739 | * state, if child is still the first entry, it didn't get freed | |
4740 | * and we can continue doing so. | |
4741 | */ | |
4742 | tmp = list_first_entry_or_null(&event->child_list, | |
4743 | struct perf_event, child_list); | |
4744 | if (tmp == child) { | |
4745 | perf_remove_from_context(child, DETACH_GROUP); | |
82d94856 | 4746 | list_move(&child->child_list, &free_list); |
c6e5b732 PZ |
4747 | /* |
4748 | * This matches the refcount bump in inherit_event(); | |
4749 | * this can't be the last reference. | |
4750 | */ | |
4751 | put_event(event); | |
4752 | } | |
4753 | ||
4754 | mutex_unlock(&event->child_mutex); | |
4755 | mutex_unlock(&ctx->mutex); | |
4756 | put_ctx(ctx); | |
4757 | goto again; | |
4758 | } | |
4759 | mutex_unlock(&event->child_mutex); | |
4760 | ||
82d94856 | 4761 | list_for_each_entry_safe(child, tmp, &free_list, child_list) { |
1cf8dfe8 PZ |
4762 | void *var = &child->ctx->refcount; |
4763 | ||
82d94856 PZ |
4764 | list_del(&child->child_list); |
4765 | free_event(child); | |
1cf8dfe8 PZ |
4766 | |
4767 | /* | |
4768 | * Wake any perf_event_free_task() waiting for this event to be | |
4769 | * freed. | |
4770 | */ | |
4771 | smp_mb(); /* pairs with wait_var_event() */ | |
4772 | wake_up_var(var); | |
82d94856 PZ |
4773 | } |
4774 | ||
a4f4bb6d PZ |
4775 | no_ctx: |
4776 | put_event(event); /* Must be the 'last' reference */ | |
683ede43 PZ |
4777 | return 0; |
4778 | } | |
4779 | EXPORT_SYMBOL_GPL(perf_event_release_kernel); | |
4780 | ||
8b10c5e2 PZ |
4781 | /* |
4782 | * Called when the last reference to the file is gone. | |
4783 | */ | |
a6fa941d AV |
4784 | static int perf_release(struct inode *inode, struct file *file) |
4785 | { | |
c6e5b732 | 4786 | perf_event_release_kernel(file->private_data); |
a6fa941d | 4787 | return 0; |
fb0459d7 | 4788 | } |
fb0459d7 | 4789 | |
ca0dd44c | 4790 | static u64 __perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) |
e53c0994 | 4791 | { |
cdd6c482 | 4792 | struct perf_event *child; |
e53c0994 PZ |
4793 | u64 total = 0; |
4794 | ||
59ed446f PZ |
4795 | *enabled = 0; |
4796 | *running = 0; | |
4797 | ||
6f10581a | 4798 | mutex_lock(&event->child_mutex); |
01add3ea | 4799 | |
7d88962e | 4800 | (void)perf_event_read(event, false); |
01add3ea SB |
4801 | total += perf_event_count(event); |
4802 | ||
59ed446f PZ |
4803 | *enabled += event->total_time_enabled + |
4804 | atomic64_read(&event->child_total_time_enabled); | |
4805 | *running += event->total_time_running + | |
4806 | atomic64_read(&event->child_total_time_running); | |
4807 | ||
4808 | list_for_each_entry(child, &event->child_list, child_list) { | |
7d88962e | 4809 | (void)perf_event_read(child, false); |
01add3ea | 4810 | total += perf_event_count(child); |
59ed446f PZ |
4811 | *enabled += child->total_time_enabled; |
4812 | *running += child->total_time_running; | |
4813 | } | |
6f10581a | 4814 | mutex_unlock(&event->child_mutex); |
e53c0994 PZ |
4815 | |
4816 | return total; | |
4817 | } | |
ca0dd44c PZ |
4818 | |
4819 | u64 perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) | |
4820 | { | |
4821 | struct perf_event_context *ctx; | |
4822 | u64 count; | |
4823 | ||
4824 | ctx = perf_event_ctx_lock(event); | |
4825 | count = __perf_event_read_value(event, enabled, running); | |
4826 | perf_event_ctx_unlock(event, ctx); | |
4827 | ||
4828 | return count; | |
4829 | } | |
fb0459d7 | 4830 | EXPORT_SYMBOL_GPL(perf_event_read_value); |
e53c0994 | 4831 | |
7d88962e | 4832 | static int __perf_read_group_add(struct perf_event *leader, |
fa8c2693 | 4833 | u64 read_format, u64 *values) |
3dab77fb | 4834 | { |
2aeb1883 | 4835 | struct perf_event_context *ctx = leader->ctx; |
fa8c2693 | 4836 | struct perf_event *sub; |
2aeb1883 | 4837 | unsigned long flags; |
fa8c2693 | 4838 | int n = 1; /* skip @nr */ |
7d88962e | 4839 | int ret; |
f63a8daa | 4840 | |
7d88962e SB |
4841 | ret = perf_event_read(leader, true); |
4842 | if (ret) | |
4843 | return ret; | |
abf4868b | 4844 | |
a9cd8194 PZ |
4845 | raw_spin_lock_irqsave(&ctx->lock, flags); |
4846 | ||
fa8c2693 PZ |
4847 | /* |
4848 | * Since we co-schedule groups, {enabled,running} times of siblings | |
4849 | * will be identical to those of the leader, so we only publish one | |
4850 | * set. | |
4851 | */ | |
4852 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { | |
4853 | values[n++] += leader->total_time_enabled + | |
4854 | atomic64_read(&leader->child_total_time_enabled); | |
4855 | } | |
3dab77fb | 4856 | |
fa8c2693 PZ |
4857 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { |
4858 | values[n++] += leader->total_time_running + | |
4859 | atomic64_read(&leader->child_total_time_running); | |
4860 | } | |
4861 | ||
4862 | /* | |
4863 | * Write {count,id} tuples for every sibling. | |
4864 | */ | |
4865 | values[n++] += perf_event_count(leader); | |
abf4868b PZ |
4866 | if (read_format & PERF_FORMAT_ID) |
4867 | values[n++] = primary_event_id(leader); | |
3dab77fb | 4868 | |
edb39592 | 4869 | for_each_sibling_event(sub, leader) { |
fa8c2693 PZ |
4870 | values[n++] += perf_event_count(sub); |
4871 | if (read_format & PERF_FORMAT_ID) | |
4872 | values[n++] = primary_event_id(sub); | |
4873 | } | |
7d88962e | 4874 | |
2aeb1883 | 4875 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
7d88962e | 4876 | return 0; |
fa8c2693 | 4877 | } |
3dab77fb | 4878 | |
fa8c2693 PZ |
4879 | static int perf_read_group(struct perf_event *event, |
4880 | u64 read_format, char __user *buf) | |
4881 | { | |
4882 | struct perf_event *leader = event->group_leader, *child; | |
4883 | struct perf_event_context *ctx = leader->ctx; | |
7d88962e | 4884 | int ret; |
fa8c2693 | 4885 | u64 *values; |
3dab77fb | 4886 | |
fa8c2693 | 4887 | lockdep_assert_held(&ctx->mutex); |
3dab77fb | 4888 | |
fa8c2693 PZ |
4889 | values = kzalloc(event->read_size, GFP_KERNEL); |
4890 | if (!values) | |
4891 | return -ENOMEM; | |
3dab77fb | 4892 | |
fa8c2693 PZ |
4893 | values[0] = 1 + leader->nr_siblings; |
4894 | ||
4895 | /* | |
4896 | * By locking the child_mutex of the leader we effectively | |
4897 | * lock the child list of all siblings.. XXX explain how. | |
4898 | */ | |
4899 | mutex_lock(&leader->child_mutex); | |
abf4868b | 4900 | |
7d88962e SB |
4901 | ret = __perf_read_group_add(leader, read_format, values); |
4902 | if (ret) | |
4903 | goto unlock; | |
4904 | ||
4905 | list_for_each_entry(child, &leader->child_list, child_list) { | |
4906 | ret = __perf_read_group_add(child, read_format, values); | |
4907 | if (ret) | |
4908 | goto unlock; | |
4909 | } | |
abf4868b | 4910 | |
fa8c2693 | 4911 | mutex_unlock(&leader->child_mutex); |
abf4868b | 4912 | |
7d88962e | 4913 | ret = event->read_size; |
fa8c2693 PZ |
4914 | if (copy_to_user(buf, values, event->read_size)) |
4915 | ret = -EFAULT; | |
7d88962e | 4916 | goto out; |
fa8c2693 | 4917 | |
7d88962e SB |
4918 | unlock: |
4919 | mutex_unlock(&leader->child_mutex); | |
4920 | out: | |
fa8c2693 | 4921 | kfree(values); |
abf4868b | 4922 | return ret; |
3dab77fb PZ |
4923 | } |
4924 | ||
b15f495b | 4925 | static int perf_read_one(struct perf_event *event, |
3dab77fb PZ |
4926 | u64 read_format, char __user *buf) |
4927 | { | |
59ed446f | 4928 | u64 enabled, running; |
3dab77fb PZ |
4929 | u64 values[4]; |
4930 | int n = 0; | |
4931 | ||
ca0dd44c | 4932 | values[n++] = __perf_event_read_value(event, &enabled, &running); |
59ed446f PZ |
4933 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) |
4934 | values[n++] = enabled; | |
4935 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
4936 | values[n++] = running; | |
3dab77fb | 4937 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 4938 | values[n++] = primary_event_id(event); |
3dab77fb PZ |
4939 | |
4940 | if (copy_to_user(buf, values, n * sizeof(u64))) | |
4941 | return -EFAULT; | |
4942 | ||
4943 | return n * sizeof(u64); | |
4944 | } | |
4945 | ||
dc633982 JO |
4946 | static bool is_event_hup(struct perf_event *event) |
4947 | { | |
4948 | bool no_children; | |
4949 | ||
a69b0ca4 | 4950 | if (event->state > PERF_EVENT_STATE_EXIT) |
dc633982 JO |
4951 | return false; |
4952 | ||
4953 | mutex_lock(&event->child_mutex); | |
4954 | no_children = list_empty(&event->child_list); | |
4955 | mutex_unlock(&event->child_mutex); | |
4956 | return no_children; | |
4957 | } | |
4958 | ||
0793a61d | 4959 | /* |
cdd6c482 | 4960 | * Read the performance event - simple non blocking version for now |
0793a61d TG |
4961 | */ |
4962 | static ssize_t | |
b15f495b | 4963 | __perf_read(struct perf_event *event, char __user *buf, size_t count) |
0793a61d | 4964 | { |
cdd6c482 | 4965 | u64 read_format = event->attr.read_format; |
3dab77fb | 4966 | int ret; |
0793a61d | 4967 | |
3b6f9e5c | 4968 | /* |
788faab7 | 4969 | * Return end-of-file for a read on an event that is in |
3b6f9e5c PM |
4970 | * error state (i.e. because it was pinned but it couldn't be |
4971 | * scheduled on to the CPU at some point). | |
4972 | */ | |
cdd6c482 | 4973 | if (event->state == PERF_EVENT_STATE_ERROR) |
3b6f9e5c PM |
4974 | return 0; |
4975 | ||
c320c7b7 | 4976 | if (count < event->read_size) |
3dab77fb PZ |
4977 | return -ENOSPC; |
4978 | ||
cdd6c482 | 4979 | WARN_ON_ONCE(event->ctx->parent_ctx); |
3dab77fb | 4980 | if (read_format & PERF_FORMAT_GROUP) |
b15f495b | 4981 | ret = perf_read_group(event, read_format, buf); |
3dab77fb | 4982 | else |
b15f495b | 4983 | ret = perf_read_one(event, read_format, buf); |
0793a61d | 4984 | |
3dab77fb | 4985 | return ret; |
0793a61d TG |
4986 | } |
4987 | ||
0793a61d TG |
4988 | static ssize_t |
4989 | perf_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) | |
4990 | { | |
cdd6c482 | 4991 | struct perf_event *event = file->private_data; |
f63a8daa PZ |
4992 | struct perf_event_context *ctx; |
4993 | int ret; | |
0793a61d | 4994 | |
f63a8daa | 4995 | ctx = perf_event_ctx_lock(event); |
b15f495b | 4996 | ret = __perf_read(event, buf, count); |
f63a8daa PZ |
4997 | perf_event_ctx_unlock(event, ctx); |
4998 | ||
4999 | return ret; | |
0793a61d TG |
5000 | } |
5001 | ||
9dd95748 | 5002 | static __poll_t perf_poll(struct file *file, poll_table *wait) |
0793a61d | 5003 | { |
cdd6c482 | 5004 | struct perf_event *event = file->private_data; |
76369139 | 5005 | struct ring_buffer *rb; |
a9a08845 | 5006 | __poll_t events = EPOLLHUP; |
c7138f37 | 5007 | |
e708d7ad | 5008 | poll_wait(file, &event->waitq, wait); |
179033b3 | 5009 | |
dc633982 | 5010 | if (is_event_hup(event)) |
179033b3 | 5011 | return events; |
c7138f37 | 5012 | |
10c6db11 | 5013 | /* |
9bb5d40c PZ |
5014 | * Pin the event->rb by taking event->mmap_mutex; otherwise |
5015 | * perf_event_set_output() can swizzle our rb and make us miss wakeups. | |
10c6db11 PZ |
5016 | */ |
5017 | mutex_lock(&event->mmap_mutex); | |
9bb5d40c PZ |
5018 | rb = event->rb; |
5019 | if (rb) | |
76369139 | 5020 | events = atomic_xchg(&rb->poll, 0); |
10c6db11 | 5021 | mutex_unlock(&event->mmap_mutex); |
0793a61d TG |
5022 | return events; |
5023 | } | |
5024 | ||
f63a8daa | 5025 | static void _perf_event_reset(struct perf_event *event) |
6de6a7b9 | 5026 | { |
7d88962e | 5027 | (void)perf_event_read(event, false); |
e7850595 | 5028 | local64_set(&event->count, 0); |
cdd6c482 | 5029 | perf_event_update_userpage(event); |
3df5edad PZ |
5030 | } |
5031 | ||
c93f7669 | 5032 | /* |
cdd6c482 IM |
5033 | * Holding the top-level event's child_mutex means that any |
5034 | * descendant process that has inherited this event will block | |
8ba289b8 | 5035 | * in perf_event_exit_event() if it goes to exit, thus satisfying the |
cdd6c482 | 5036 | * task existence requirements of perf_event_enable/disable. |
c93f7669 | 5037 | */ |
cdd6c482 IM |
5038 | static void perf_event_for_each_child(struct perf_event *event, |
5039 | void (*func)(struct perf_event *)) | |
3df5edad | 5040 | { |
cdd6c482 | 5041 | struct perf_event *child; |
3df5edad | 5042 | |
cdd6c482 | 5043 | WARN_ON_ONCE(event->ctx->parent_ctx); |
f63a8daa | 5044 | |
cdd6c482 IM |
5045 | mutex_lock(&event->child_mutex); |
5046 | func(event); | |
5047 | list_for_each_entry(child, &event->child_list, child_list) | |
3df5edad | 5048 | func(child); |
cdd6c482 | 5049 | mutex_unlock(&event->child_mutex); |
3df5edad PZ |
5050 | } |
5051 | ||
cdd6c482 IM |
5052 | static void perf_event_for_each(struct perf_event *event, |
5053 | void (*func)(struct perf_event *)) | |
3df5edad | 5054 | { |
cdd6c482 IM |
5055 | struct perf_event_context *ctx = event->ctx; |
5056 | struct perf_event *sibling; | |
3df5edad | 5057 | |
f63a8daa PZ |
5058 | lockdep_assert_held(&ctx->mutex); |
5059 | ||
cdd6c482 | 5060 | event = event->group_leader; |
75f937f2 | 5061 | |
cdd6c482 | 5062 | perf_event_for_each_child(event, func); |
edb39592 | 5063 | for_each_sibling_event(sibling, event) |
724b6daa | 5064 | perf_event_for_each_child(sibling, func); |
6de6a7b9 PZ |
5065 | } |
5066 | ||
fae3fde6 PZ |
5067 | static void __perf_event_period(struct perf_event *event, |
5068 | struct perf_cpu_context *cpuctx, | |
5069 | struct perf_event_context *ctx, | |
5070 | void *info) | |
c7999c6f | 5071 | { |
fae3fde6 | 5072 | u64 value = *((u64 *)info); |
c7999c6f | 5073 | bool active; |
08247e31 | 5074 | |
cdd6c482 | 5075 | if (event->attr.freq) { |
cdd6c482 | 5076 | event->attr.sample_freq = value; |
08247e31 | 5077 | } else { |
cdd6c482 IM |
5078 | event->attr.sample_period = value; |
5079 | event->hw.sample_period = value; | |
08247e31 | 5080 | } |
bad7192b PZ |
5081 | |
5082 | active = (event->state == PERF_EVENT_STATE_ACTIVE); | |
5083 | if (active) { | |
5084 | perf_pmu_disable(ctx->pmu); | |
1e02cd40 PZ |
5085 | /* |
5086 | * We could be throttled; unthrottle now to avoid the tick | |
5087 | * trying to unthrottle while we already re-started the event. | |
5088 | */ | |
5089 | if (event->hw.interrupts == MAX_INTERRUPTS) { | |
5090 | event->hw.interrupts = 0; | |
5091 | perf_log_throttle(event, 1); | |
5092 | } | |
bad7192b PZ |
5093 | event->pmu->stop(event, PERF_EF_UPDATE); |
5094 | } | |
5095 | ||
5096 | local64_set(&event->hw.period_left, 0); | |
5097 | ||
5098 | if (active) { | |
5099 | event->pmu->start(event, PERF_EF_RELOAD); | |
5100 | perf_pmu_enable(ctx->pmu); | |
5101 | } | |
c7999c6f PZ |
5102 | } |
5103 | ||
81ec3f3c JO |
5104 | static int perf_event_check_period(struct perf_event *event, u64 value) |
5105 | { | |
5106 | return event->pmu->check_period(event, value); | |
5107 | } | |
5108 | ||
c7999c6f PZ |
5109 | static int perf_event_period(struct perf_event *event, u64 __user *arg) |
5110 | { | |
c7999c6f PZ |
5111 | u64 value; |
5112 | ||
5113 | if (!is_sampling_event(event)) | |
5114 | return -EINVAL; | |
5115 | ||
5116 | if (copy_from_user(&value, arg, sizeof(value))) | |
5117 | return -EFAULT; | |
5118 | ||
5119 | if (!value) | |
5120 | return -EINVAL; | |
5121 | ||
5122 | if (event->attr.freq && value > sysctl_perf_event_sample_rate) | |
5123 | return -EINVAL; | |
5124 | ||
81ec3f3c JO |
5125 | if (perf_event_check_period(event, value)) |
5126 | return -EINVAL; | |
5127 | ||
913a90bc RB |
5128 | if (!event->attr.freq && (value & (1ULL << 63))) |
5129 | return -EINVAL; | |
5130 | ||
fae3fde6 | 5131 | event_function_call(event, __perf_event_period, &value); |
08247e31 | 5132 | |
c7999c6f | 5133 | return 0; |
08247e31 PZ |
5134 | } |
5135 | ||
ac9721f3 PZ |
5136 | static const struct file_operations perf_fops; |
5137 | ||
2903ff01 | 5138 | static inline int perf_fget_light(int fd, struct fd *p) |
ac9721f3 | 5139 | { |
2903ff01 AV |
5140 | struct fd f = fdget(fd); |
5141 | if (!f.file) | |
5142 | return -EBADF; | |
ac9721f3 | 5143 | |
2903ff01 AV |
5144 | if (f.file->f_op != &perf_fops) { |
5145 | fdput(f); | |
5146 | return -EBADF; | |
ac9721f3 | 5147 | } |
2903ff01 AV |
5148 | *p = f; |
5149 | return 0; | |
ac9721f3 PZ |
5150 | } |
5151 | ||
5152 | static int perf_event_set_output(struct perf_event *event, | |
5153 | struct perf_event *output_event); | |
6fb2915d | 5154 | static int perf_event_set_filter(struct perf_event *event, void __user *arg); |
2541517c | 5155 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd); |
32ff77e8 MC |
5156 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
5157 | struct perf_event_attr *attr); | |
a4be7c27 | 5158 | |
f63a8daa | 5159 | static long _perf_ioctl(struct perf_event *event, unsigned int cmd, unsigned long arg) |
d859e29f | 5160 | { |
cdd6c482 | 5161 | void (*func)(struct perf_event *); |
3df5edad | 5162 | u32 flags = arg; |
d859e29f PM |
5163 | |
5164 | switch (cmd) { | |
cdd6c482 | 5165 | case PERF_EVENT_IOC_ENABLE: |
f63a8daa | 5166 | func = _perf_event_enable; |
d859e29f | 5167 | break; |
cdd6c482 | 5168 | case PERF_EVENT_IOC_DISABLE: |
f63a8daa | 5169 | func = _perf_event_disable; |
79f14641 | 5170 | break; |
cdd6c482 | 5171 | case PERF_EVENT_IOC_RESET: |
f63a8daa | 5172 | func = _perf_event_reset; |
6de6a7b9 | 5173 | break; |
3df5edad | 5174 | |
cdd6c482 | 5175 | case PERF_EVENT_IOC_REFRESH: |
f63a8daa | 5176 | return _perf_event_refresh(event, arg); |
08247e31 | 5177 | |
cdd6c482 IM |
5178 | case PERF_EVENT_IOC_PERIOD: |
5179 | return perf_event_period(event, (u64 __user *)arg); | |
08247e31 | 5180 | |
cf4957f1 JO |
5181 | case PERF_EVENT_IOC_ID: |
5182 | { | |
5183 | u64 id = primary_event_id(event); | |
5184 | ||
5185 | if (copy_to_user((void __user *)arg, &id, sizeof(id))) | |
5186 | return -EFAULT; | |
5187 | return 0; | |
5188 | } | |
5189 | ||
cdd6c482 | 5190 | case PERF_EVENT_IOC_SET_OUTPUT: |
ac9721f3 | 5191 | { |
ac9721f3 | 5192 | int ret; |
ac9721f3 | 5193 | if (arg != -1) { |
2903ff01 AV |
5194 | struct perf_event *output_event; |
5195 | struct fd output; | |
5196 | ret = perf_fget_light(arg, &output); | |
5197 | if (ret) | |
5198 | return ret; | |
5199 | output_event = output.file->private_data; | |
5200 | ret = perf_event_set_output(event, output_event); | |
5201 | fdput(output); | |
5202 | } else { | |
5203 | ret = perf_event_set_output(event, NULL); | |
ac9721f3 | 5204 | } |
ac9721f3 PZ |
5205 | return ret; |
5206 | } | |
a4be7c27 | 5207 | |
6fb2915d LZ |
5208 | case PERF_EVENT_IOC_SET_FILTER: |
5209 | return perf_event_set_filter(event, (void __user *)arg); | |
5210 | ||
2541517c AS |
5211 | case PERF_EVENT_IOC_SET_BPF: |
5212 | return perf_event_set_bpf_prog(event, arg); | |
5213 | ||
86e7972f WN |
5214 | case PERF_EVENT_IOC_PAUSE_OUTPUT: { |
5215 | struct ring_buffer *rb; | |
5216 | ||
5217 | rcu_read_lock(); | |
5218 | rb = rcu_dereference(event->rb); | |
5219 | if (!rb || !rb->nr_pages) { | |
5220 | rcu_read_unlock(); | |
5221 | return -EINVAL; | |
5222 | } | |
5223 | rb_toggle_paused(rb, !!arg); | |
5224 | rcu_read_unlock(); | |
5225 | return 0; | |
5226 | } | |
f371b304 YS |
5227 | |
5228 | case PERF_EVENT_IOC_QUERY_BPF: | |
f4e2298e | 5229 | return perf_event_query_prog_array(event, (void __user *)arg); |
32ff77e8 MC |
5230 | |
5231 | case PERF_EVENT_IOC_MODIFY_ATTRIBUTES: { | |
5232 | struct perf_event_attr new_attr; | |
5233 | int err = perf_copy_attr((struct perf_event_attr __user *)arg, | |
5234 | &new_attr); | |
5235 | ||
5236 | if (err) | |
5237 | return err; | |
5238 | ||
5239 | return perf_event_modify_attr(event, &new_attr); | |
5240 | } | |
d859e29f | 5241 | default: |
3df5edad | 5242 | return -ENOTTY; |
d859e29f | 5243 | } |
3df5edad PZ |
5244 | |
5245 | if (flags & PERF_IOC_FLAG_GROUP) | |
cdd6c482 | 5246 | perf_event_for_each(event, func); |
3df5edad | 5247 | else |
cdd6c482 | 5248 | perf_event_for_each_child(event, func); |
3df5edad PZ |
5249 | |
5250 | return 0; | |
d859e29f PM |
5251 | } |
5252 | ||
f63a8daa PZ |
5253 | static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
5254 | { | |
5255 | struct perf_event *event = file->private_data; | |
5256 | struct perf_event_context *ctx; | |
5257 | long ret; | |
5258 | ||
5259 | ctx = perf_event_ctx_lock(event); | |
5260 | ret = _perf_ioctl(event, cmd, arg); | |
5261 | perf_event_ctx_unlock(event, ctx); | |
5262 | ||
5263 | return ret; | |
5264 | } | |
5265 | ||
b3f20785 PM |
5266 | #ifdef CONFIG_COMPAT |
5267 | static long perf_compat_ioctl(struct file *file, unsigned int cmd, | |
5268 | unsigned long arg) | |
5269 | { | |
5270 | switch (_IOC_NR(cmd)) { | |
5271 | case _IOC_NR(PERF_EVENT_IOC_SET_FILTER): | |
5272 | case _IOC_NR(PERF_EVENT_IOC_ID): | |
82489c5f ES |
5273 | case _IOC_NR(PERF_EVENT_IOC_QUERY_BPF): |
5274 | case _IOC_NR(PERF_EVENT_IOC_MODIFY_ATTRIBUTES): | |
b3f20785 PM |
5275 | /* Fix up pointer size (usually 4 -> 8 in 32-on-64-bit case */ |
5276 | if (_IOC_SIZE(cmd) == sizeof(compat_uptr_t)) { | |
5277 | cmd &= ~IOCSIZE_MASK; | |
5278 | cmd |= sizeof(void *) << IOCSIZE_SHIFT; | |
5279 | } | |
5280 | break; | |
5281 | } | |
5282 | return perf_ioctl(file, cmd, arg); | |
5283 | } | |
5284 | #else | |
5285 | # define perf_compat_ioctl NULL | |
5286 | #endif | |
5287 | ||
cdd6c482 | 5288 | int perf_event_task_enable(void) |
771d7cde | 5289 | { |
f63a8daa | 5290 | struct perf_event_context *ctx; |
cdd6c482 | 5291 | struct perf_event *event; |
771d7cde | 5292 | |
cdd6c482 | 5293 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
5294 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
5295 | ctx = perf_event_ctx_lock(event); | |
5296 | perf_event_for_each_child(event, _perf_event_enable); | |
5297 | perf_event_ctx_unlock(event, ctx); | |
5298 | } | |
cdd6c482 | 5299 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
5300 | |
5301 | return 0; | |
5302 | } | |
5303 | ||
cdd6c482 | 5304 | int perf_event_task_disable(void) |
771d7cde | 5305 | { |
f63a8daa | 5306 | struct perf_event_context *ctx; |
cdd6c482 | 5307 | struct perf_event *event; |
771d7cde | 5308 | |
cdd6c482 | 5309 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
5310 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
5311 | ctx = perf_event_ctx_lock(event); | |
5312 | perf_event_for_each_child(event, _perf_event_disable); | |
5313 | perf_event_ctx_unlock(event, ctx); | |
5314 | } | |
cdd6c482 | 5315 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
5316 | |
5317 | return 0; | |
5318 | } | |
5319 | ||
cdd6c482 | 5320 | static int perf_event_index(struct perf_event *event) |
194002b2 | 5321 | { |
a4eaf7f1 PZ |
5322 | if (event->hw.state & PERF_HES_STOPPED) |
5323 | return 0; | |
5324 | ||
cdd6c482 | 5325 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
194002b2 PZ |
5326 | return 0; |
5327 | ||
35edc2a5 | 5328 | return event->pmu->event_idx(event); |
194002b2 PZ |
5329 | } |
5330 | ||
c4794295 | 5331 | static void calc_timer_values(struct perf_event *event, |
e3f3541c | 5332 | u64 *now, |
7f310a5d EM |
5333 | u64 *enabled, |
5334 | u64 *running) | |
c4794295 | 5335 | { |
e3f3541c | 5336 | u64 ctx_time; |
c4794295 | 5337 | |
e3f3541c PZ |
5338 | *now = perf_clock(); |
5339 | ctx_time = event->shadow_ctx_time + *now; | |
0d3d73aa | 5340 | __perf_update_times(event, ctx_time, enabled, running); |
c4794295 EM |
5341 | } |
5342 | ||
fa731587 PZ |
5343 | static void perf_event_init_userpage(struct perf_event *event) |
5344 | { | |
5345 | struct perf_event_mmap_page *userpg; | |
5346 | struct ring_buffer *rb; | |
5347 | ||
5348 | rcu_read_lock(); | |
5349 | rb = rcu_dereference(event->rb); | |
5350 | if (!rb) | |
5351 | goto unlock; | |
5352 | ||
5353 | userpg = rb->user_page; | |
5354 | ||
5355 | /* Allow new userspace to detect that bit 0 is deprecated */ | |
5356 | userpg->cap_bit0_is_deprecated = 1; | |
5357 | userpg->size = offsetof(struct perf_event_mmap_page, __reserved); | |
e8c6deac AS |
5358 | userpg->data_offset = PAGE_SIZE; |
5359 | userpg->data_size = perf_data_size(rb); | |
fa731587 PZ |
5360 | |
5361 | unlock: | |
5362 | rcu_read_unlock(); | |
5363 | } | |
5364 | ||
c1317ec2 AL |
5365 | void __weak arch_perf_update_userpage( |
5366 | struct perf_event *event, struct perf_event_mmap_page *userpg, u64 now) | |
e3f3541c PZ |
5367 | { |
5368 | } | |
5369 | ||
38ff667b PZ |
5370 | /* |
5371 | * Callers need to ensure there can be no nesting of this function, otherwise | |
5372 | * the seqlock logic goes bad. We can not serialize this because the arch | |
5373 | * code calls this from NMI context. | |
5374 | */ | |
cdd6c482 | 5375 | void perf_event_update_userpage(struct perf_event *event) |
37d81828 | 5376 | { |
cdd6c482 | 5377 | struct perf_event_mmap_page *userpg; |
76369139 | 5378 | struct ring_buffer *rb; |
e3f3541c | 5379 | u64 enabled, running, now; |
38ff667b PZ |
5380 | |
5381 | rcu_read_lock(); | |
5ec4c599 PZ |
5382 | rb = rcu_dereference(event->rb); |
5383 | if (!rb) | |
5384 | goto unlock; | |
5385 | ||
0d641208 EM |
5386 | /* |
5387 | * compute total_time_enabled, total_time_running | |
5388 | * based on snapshot values taken when the event | |
5389 | * was last scheduled in. | |
5390 | * | |
5391 | * we cannot simply called update_context_time() | |
5392 | * because of locking issue as we can be called in | |
5393 | * NMI context | |
5394 | */ | |
e3f3541c | 5395 | calc_timer_values(event, &now, &enabled, &running); |
38ff667b | 5396 | |
76369139 | 5397 | userpg = rb->user_page; |
7b732a75 | 5398 | /* |
9d2dcc8f MF |
5399 | * Disable preemption to guarantee consistent time stamps are stored to |
5400 | * the user page. | |
7b732a75 PZ |
5401 | */ |
5402 | preempt_disable(); | |
37d81828 | 5403 | ++userpg->lock; |
92f22a38 | 5404 | barrier(); |
cdd6c482 | 5405 | userpg->index = perf_event_index(event); |
b5e58793 | 5406 | userpg->offset = perf_event_count(event); |
365a4038 | 5407 | if (userpg->index) |
e7850595 | 5408 | userpg->offset -= local64_read(&event->hw.prev_count); |
7b732a75 | 5409 | |
0d641208 | 5410 | userpg->time_enabled = enabled + |
cdd6c482 | 5411 | atomic64_read(&event->child_total_time_enabled); |
7f8b4e4e | 5412 | |
0d641208 | 5413 | userpg->time_running = running + |
cdd6c482 | 5414 | atomic64_read(&event->child_total_time_running); |
7f8b4e4e | 5415 | |
c1317ec2 | 5416 | arch_perf_update_userpage(event, userpg, now); |
e3f3541c | 5417 | |
92f22a38 | 5418 | barrier(); |
37d81828 | 5419 | ++userpg->lock; |
7b732a75 | 5420 | preempt_enable(); |
38ff667b | 5421 | unlock: |
7b732a75 | 5422 | rcu_read_unlock(); |
37d81828 | 5423 | } |
82975c46 | 5424 | EXPORT_SYMBOL_GPL(perf_event_update_userpage); |
37d81828 | 5425 | |
9e3ed2d7 | 5426 | static vm_fault_t perf_mmap_fault(struct vm_fault *vmf) |
906010b2 | 5427 | { |
11bac800 | 5428 | struct perf_event *event = vmf->vma->vm_file->private_data; |
76369139 | 5429 | struct ring_buffer *rb; |
9e3ed2d7 | 5430 | vm_fault_t ret = VM_FAULT_SIGBUS; |
906010b2 PZ |
5431 | |
5432 | if (vmf->flags & FAULT_FLAG_MKWRITE) { | |
5433 | if (vmf->pgoff == 0) | |
5434 | ret = 0; | |
5435 | return ret; | |
5436 | } | |
5437 | ||
5438 | rcu_read_lock(); | |
76369139 FW |
5439 | rb = rcu_dereference(event->rb); |
5440 | if (!rb) | |
906010b2 PZ |
5441 | goto unlock; |
5442 | ||
5443 | if (vmf->pgoff && (vmf->flags & FAULT_FLAG_WRITE)) | |
5444 | goto unlock; | |
5445 | ||
76369139 | 5446 | vmf->page = perf_mmap_to_page(rb, vmf->pgoff); |
906010b2 PZ |
5447 | if (!vmf->page) |
5448 | goto unlock; | |
5449 | ||
5450 | get_page(vmf->page); | |
11bac800 | 5451 | vmf->page->mapping = vmf->vma->vm_file->f_mapping; |
906010b2 PZ |
5452 | vmf->page->index = vmf->pgoff; |
5453 | ||
5454 | ret = 0; | |
5455 | unlock: | |
5456 | rcu_read_unlock(); | |
5457 | ||
5458 | return ret; | |
5459 | } | |
5460 | ||
10c6db11 PZ |
5461 | static void ring_buffer_attach(struct perf_event *event, |
5462 | struct ring_buffer *rb) | |
5463 | { | |
b69cf536 | 5464 | struct ring_buffer *old_rb = NULL; |
10c6db11 PZ |
5465 | unsigned long flags; |
5466 | ||
b69cf536 PZ |
5467 | if (event->rb) { |
5468 | /* | |
5469 | * Should be impossible, we set this when removing | |
5470 | * event->rb_entry and wait/clear when adding event->rb_entry. | |
5471 | */ | |
5472 | WARN_ON_ONCE(event->rcu_pending); | |
10c6db11 | 5473 | |
b69cf536 | 5474 | old_rb = event->rb; |
b69cf536 PZ |
5475 | spin_lock_irqsave(&old_rb->event_lock, flags); |
5476 | list_del_rcu(&event->rb_entry); | |
5477 | spin_unlock_irqrestore(&old_rb->event_lock, flags); | |
10c6db11 | 5478 | |
2f993cf0 ON |
5479 | event->rcu_batches = get_state_synchronize_rcu(); |
5480 | event->rcu_pending = 1; | |
b69cf536 | 5481 | } |
10c6db11 | 5482 | |
b69cf536 | 5483 | if (rb) { |
2f993cf0 ON |
5484 | if (event->rcu_pending) { |
5485 | cond_synchronize_rcu(event->rcu_batches); | |
5486 | event->rcu_pending = 0; | |
5487 | } | |
5488 | ||
b69cf536 PZ |
5489 | spin_lock_irqsave(&rb->event_lock, flags); |
5490 | list_add_rcu(&event->rb_entry, &rb->event_list); | |
5491 | spin_unlock_irqrestore(&rb->event_lock, flags); | |
5492 | } | |
5493 | ||
767ae086 AS |
5494 | /* |
5495 | * Avoid racing with perf_mmap_close(AUX): stop the event | |
5496 | * before swizzling the event::rb pointer; if it's getting | |
5497 | * unmapped, its aux_mmap_count will be 0 and it won't | |
5498 | * restart. See the comment in __perf_pmu_output_stop(). | |
5499 | * | |
5500 | * Data will inevitably be lost when set_output is done in | |
5501 | * mid-air, but then again, whoever does it like this is | |
5502 | * not in for the data anyway. | |
5503 | */ | |
5504 | if (has_aux(event)) | |
5505 | perf_event_stop(event, 0); | |
5506 | ||
b69cf536 PZ |
5507 | rcu_assign_pointer(event->rb, rb); |
5508 | ||
5509 | if (old_rb) { | |
5510 | ring_buffer_put(old_rb); | |
5511 | /* | |
5512 | * Since we detached before setting the new rb, so that we | |
5513 | * could attach the new rb, we could have missed a wakeup. | |
5514 | * Provide it now. | |
5515 | */ | |
5516 | wake_up_all(&event->waitq); | |
5517 | } | |
10c6db11 PZ |
5518 | } |
5519 | ||
5520 | static void ring_buffer_wakeup(struct perf_event *event) | |
5521 | { | |
5522 | struct ring_buffer *rb; | |
5523 | ||
5524 | rcu_read_lock(); | |
5525 | rb = rcu_dereference(event->rb); | |
9bb5d40c PZ |
5526 | if (rb) { |
5527 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) | |
5528 | wake_up_all(&event->waitq); | |
5529 | } | |
10c6db11 PZ |
5530 | rcu_read_unlock(); |
5531 | } | |
5532 | ||
fdc26706 | 5533 | struct ring_buffer *ring_buffer_get(struct perf_event *event) |
7b732a75 | 5534 | { |
76369139 | 5535 | struct ring_buffer *rb; |
7b732a75 | 5536 | |
ac9721f3 | 5537 | rcu_read_lock(); |
76369139 FW |
5538 | rb = rcu_dereference(event->rb); |
5539 | if (rb) { | |
fecb8ed2 | 5540 | if (!refcount_inc_not_zero(&rb->refcount)) |
76369139 | 5541 | rb = NULL; |
ac9721f3 PZ |
5542 | } |
5543 | rcu_read_unlock(); | |
5544 | ||
76369139 | 5545 | return rb; |
ac9721f3 PZ |
5546 | } |
5547 | ||
fdc26706 | 5548 | void ring_buffer_put(struct ring_buffer *rb) |
ac9721f3 | 5549 | { |
fecb8ed2 | 5550 | if (!refcount_dec_and_test(&rb->refcount)) |
ac9721f3 | 5551 | return; |
7b732a75 | 5552 | |
9bb5d40c | 5553 | WARN_ON_ONCE(!list_empty(&rb->event_list)); |
10c6db11 | 5554 | |
76369139 | 5555 | call_rcu(&rb->rcu_head, rb_free_rcu); |
7b732a75 PZ |
5556 | } |
5557 | ||
5558 | static void perf_mmap_open(struct vm_area_struct *vma) | |
5559 | { | |
cdd6c482 | 5560 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 5561 | |
cdd6c482 | 5562 | atomic_inc(&event->mmap_count); |
9bb5d40c | 5563 | atomic_inc(&event->rb->mmap_count); |
1e0fb9ec | 5564 | |
45bfb2e5 PZ |
5565 | if (vma->vm_pgoff) |
5566 | atomic_inc(&event->rb->aux_mmap_count); | |
5567 | ||
1e0fb9ec | 5568 | if (event->pmu->event_mapped) |
bfe33492 | 5569 | event->pmu->event_mapped(event, vma->vm_mm); |
7b732a75 PZ |
5570 | } |
5571 | ||
95ff4ca2 AS |
5572 | static void perf_pmu_output_stop(struct perf_event *event); |
5573 | ||
9bb5d40c PZ |
5574 | /* |
5575 | * A buffer can be mmap()ed multiple times; either directly through the same | |
5576 | * event, or through other events by use of perf_event_set_output(). | |
5577 | * | |
5578 | * In order to undo the VM accounting done by perf_mmap() we need to destroy | |
5579 | * the buffer here, where we still have a VM context. This means we need | |
5580 | * to detach all events redirecting to us. | |
5581 | */ | |
7b732a75 PZ |
5582 | static void perf_mmap_close(struct vm_area_struct *vma) |
5583 | { | |
cdd6c482 | 5584 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 5585 | |
b69cf536 | 5586 | struct ring_buffer *rb = ring_buffer_get(event); |
9bb5d40c PZ |
5587 | struct user_struct *mmap_user = rb->mmap_user; |
5588 | int mmap_locked = rb->mmap_locked; | |
5589 | unsigned long size = perf_data_size(rb); | |
789f90fc | 5590 | |
1e0fb9ec | 5591 | if (event->pmu->event_unmapped) |
bfe33492 | 5592 | event->pmu->event_unmapped(event, vma->vm_mm); |
1e0fb9ec | 5593 | |
45bfb2e5 PZ |
5594 | /* |
5595 | * rb->aux_mmap_count will always drop before rb->mmap_count and | |
5596 | * event->mmap_count, so it is ok to use event->mmap_mutex to | |
5597 | * serialize with perf_mmap here. | |
5598 | */ | |
5599 | if (rb_has_aux(rb) && vma->vm_pgoff == rb->aux_pgoff && | |
5600 | atomic_dec_and_mutex_lock(&rb->aux_mmap_count, &event->mmap_mutex)) { | |
95ff4ca2 AS |
5601 | /* |
5602 | * Stop all AUX events that are writing to this buffer, | |
5603 | * so that we can free its AUX pages and corresponding PMU | |
5604 | * data. Note that after rb::aux_mmap_count dropped to zero, | |
5605 | * they won't start any more (see perf_aux_output_begin()). | |
5606 | */ | |
5607 | perf_pmu_output_stop(event); | |
5608 | ||
5609 | /* now it's safe to free the pages */ | |
5e6c3c7b TR |
5610 | if (!rb->aux_mmap_locked) |
5611 | atomic_long_sub(rb->aux_nr_pages, &mmap_user->locked_vm); | |
5612 | else | |
5613 | atomic64_sub(rb->aux_mmap_locked, &vma->vm_mm->pinned_vm); | |
45bfb2e5 | 5614 | |
95ff4ca2 | 5615 | /* this has to be the last one */ |
45bfb2e5 | 5616 | rb_free_aux(rb); |
ca3bb3d0 | 5617 | WARN_ON_ONCE(refcount_read(&rb->aux_refcount)); |
95ff4ca2 | 5618 | |
45bfb2e5 PZ |
5619 | mutex_unlock(&event->mmap_mutex); |
5620 | } | |
5621 | ||
9bb5d40c PZ |
5622 | atomic_dec(&rb->mmap_count); |
5623 | ||
5624 | if (!atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex)) | |
b69cf536 | 5625 | goto out_put; |
9bb5d40c | 5626 | |
b69cf536 | 5627 | ring_buffer_attach(event, NULL); |
9bb5d40c PZ |
5628 | mutex_unlock(&event->mmap_mutex); |
5629 | ||
5630 | /* If there's still other mmap()s of this buffer, we're done. */ | |
b69cf536 PZ |
5631 | if (atomic_read(&rb->mmap_count)) |
5632 | goto out_put; | |
ac9721f3 | 5633 | |
9bb5d40c PZ |
5634 | /* |
5635 | * No other mmap()s, detach from all other events that might redirect | |
5636 | * into the now unreachable buffer. Somewhat complicated by the | |
5637 | * fact that rb::event_lock otherwise nests inside mmap_mutex. | |
5638 | */ | |
5639 | again: | |
5640 | rcu_read_lock(); | |
5641 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) { | |
5642 | if (!atomic_long_inc_not_zero(&event->refcount)) { | |
5643 | /* | |
5644 | * This event is en-route to free_event() which will | |
5645 | * detach it and remove it from the list. | |
5646 | */ | |
5647 | continue; | |
5648 | } | |
5649 | rcu_read_unlock(); | |
789f90fc | 5650 | |
9bb5d40c PZ |
5651 | mutex_lock(&event->mmap_mutex); |
5652 | /* | |
5653 | * Check we didn't race with perf_event_set_output() which can | |
5654 | * swizzle the rb from under us while we were waiting to | |
5655 | * acquire mmap_mutex. | |
5656 | * | |
5657 | * If we find a different rb; ignore this event, a next | |
5658 | * iteration will no longer find it on the list. We have to | |
5659 | * still restart the iteration to make sure we're not now | |
5660 | * iterating the wrong list. | |
5661 | */ | |
b69cf536 PZ |
5662 | if (event->rb == rb) |
5663 | ring_buffer_attach(event, NULL); | |
5664 | ||
cdd6c482 | 5665 | mutex_unlock(&event->mmap_mutex); |
9bb5d40c | 5666 | put_event(event); |
ac9721f3 | 5667 | |
9bb5d40c PZ |
5668 | /* |
5669 | * Restart the iteration; either we're on the wrong list or | |
5670 | * destroyed its integrity by doing a deletion. | |
5671 | */ | |
5672 | goto again; | |
7b732a75 | 5673 | } |
9bb5d40c PZ |
5674 | rcu_read_unlock(); |
5675 | ||
5676 | /* | |
5677 | * It could be there's still a few 0-ref events on the list; they'll | |
5678 | * get cleaned up by free_event() -- they'll also still have their | |
5679 | * ref on the rb and will free it whenever they are done with it. | |
5680 | * | |
5681 | * Aside from that, this buffer is 'fully' detached and unmapped, | |
5682 | * undo the VM accounting. | |
5683 | */ | |
5684 | ||
d44248a4 SL |
5685 | atomic_long_sub((size >> PAGE_SHIFT) + 1 - mmap_locked, |
5686 | &mmap_user->locked_vm); | |
70f8a3ca | 5687 | atomic64_sub(mmap_locked, &vma->vm_mm->pinned_vm); |
9bb5d40c PZ |
5688 | free_uid(mmap_user); |
5689 | ||
b69cf536 | 5690 | out_put: |
9bb5d40c | 5691 | ring_buffer_put(rb); /* could be last */ |
37d81828 PM |
5692 | } |
5693 | ||
f0f37e2f | 5694 | static const struct vm_operations_struct perf_mmap_vmops = { |
43a21ea8 | 5695 | .open = perf_mmap_open, |
fca0c116 | 5696 | .close = perf_mmap_close, /* non mergeable */ |
43a21ea8 PZ |
5697 | .fault = perf_mmap_fault, |
5698 | .page_mkwrite = perf_mmap_fault, | |
37d81828 PM |
5699 | }; |
5700 | ||
5701 | static int perf_mmap(struct file *file, struct vm_area_struct *vma) | |
5702 | { | |
cdd6c482 | 5703 | struct perf_event *event = file->private_data; |
22a4f650 | 5704 | unsigned long user_locked, user_lock_limit; |
789f90fc | 5705 | struct user_struct *user = current_user(); |
22a4f650 | 5706 | unsigned long locked, lock_limit; |
45bfb2e5 | 5707 | struct ring_buffer *rb = NULL; |
7b732a75 PZ |
5708 | unsigned long vma_size; |
5709 | unsigned long nr_pages; | |
45bfb2e5 | 5710 | long user_extra = 0, extra = 0; |
d57e34fd | 5711 | int ret = 0, flags = 0; |
37d81828 | 5712 | |
c7920614 PZ |
5713 | /* |
5714 | * Don't allow mmap() of inherited per-task counters. This would | |
5715 | * create a performance issue due to all children writing to the | |
76369139 | 5716 | * same rb. |
c7920614 PZ |
5717 | */ |
5718 | if (event->cpu == -1 && event->attr.inherit) | |
5719 | return -EINVAL; | |
5720 | ||
43a21ea8 | 5721 | if (!(vma->vm_flags & VM_SHARED)) |
37d81828 | 5722 | return -EINVAL; |
7b732a75 PZ |
5723 | |
5724 | vma_size = vma->vm_end - vma->vm_start; | |
45bfb2e5 PZ |
5725 | |
5726 | if (vma->vm_pgoff == 0) { | |
5727 | nr_pages = (vma_size / PAGE_SIZE) - 1; | |
5728 | } else { | |
5729 | /* | |
5730 | * AUX area mapping: if rb->aux_nr_pages != 0, it's already | |
5731 | * mapped, all subsequent mappings should have the same size | |
5732 | * and offset. Must be above the normal perf buffer. | |
5733 | */ | |
5734 | u64 aux_offset, aux_size; | |
5735 | ||
5736 | if (!event->rb) | |
5737 | return -EINVAL; | |
5738 | ||
5739 | nr_pages = vma_size / PAGE_SIZE; | |
5740 | ||
5741 | mutex_lock(&event->mmap_mutex); | |
5742 | ret = -EINVAL; | |
5743 | ||
5744 | rb = event->rb; | |
5745 | if (!rb) | |
5746 | goto aux_unlock; | |
5747 | ||
6aa7de05 MR |
5748 | aux_offset = READ_ONCE(rb->user_page->aux_offset); |
5749 | aux_size = READ_ONCE(rb->user_page->aux_size); | |
45bfb2e5 PZ |
5750 | |
5751 | if (aux_offset < perf_data_size(rb) + PAGE_SIZE) | |
5752 | goto aux_unlock; | |
5753 | ||
5754 | if (aux_offset != vma->vm_pgoff << PAGE_SHIFT) | |
5755 | goto aux_unlock; | |
5756 | ||
5757 | /* already mapped with a different offset */ | |
5758 | if (rb_has_aux(rb) && rb->aux_pgoff != vma->vm_pgoff) | |
5759 | goto aux_unlock; | |
5760 | ||
5761 | if (aux_size != vma_size || aux_size != nr_pages * PAGE_SIZE) | |
5762 | goto aux_unlock; | |
5763 | ||
5764 | /* already mapped with a different size */ | |
5765 | if (rb_has_aux(rb) && rb->aux_nr_pages != nr_pages) | |
5766 | goto aux_unlock; | |
5767 | ||
5768 | if (!is_power_of_2(nr_pages)) | |
5769 | goto aux_unlock; | |
5770 | ||
5771 | if (!atomic_inc_not_zero(&rb->mmap_count)) | |
5772 | goto aux_unlock; | |
5773 | ||
5774 | if (rb_has_aux(rb)) { | |
5775 | atomic_inc(&rb->aux_mmap_count); | |
5776 | ret = 0; | |
5777 | goto unlock; | |
5778 | } | |
5779 | ||
5780 | atomic_set(&rb->aux_mmap_count, 1); | |
5781 | user_extra = nr_pages; | |
5782 | ||
5783 | goto accounting; | |
5784 | } | |
7b732a75 | 5785 | |
7730d865 | 5786 | /* |
76369139 | 5787 | * If we have rb pages ensure they're a power-of-two number, so we |
7730d865 PZ |
5788 | * can do bitmasks instead of modulo. |
5789 | */ | |
2ed11312 | 5790 | if (nr_pages != 0 && !is_power_of_2(nr_pages)) |
37d81828 PM |
5791 | return -EINVAL; |
5792 | ||
7b732a75 | 5793 | if (vma_size != PAGE_SIZE * (1 + nr_pages)) |
37d81828 PM |
5794 | return -EINVAL; |
5795 | ||
cdd6c482 | 5796 | WARN_ON_ONCE(event->ctx->parent_ctx); |
9bb5d40c | 5797 | again: |
cdd6c482 | 5798 | mutex_lock(&event->mmap_mutex); |
76369139 | 5799 | if (event->rb) { |
9bb5d40c | 5800 | if (event->rb->nr_pages != nr_pages) { |
ebb3c4c4 | 5801 | ret = -EINVAL; |
9bb5d40c PZ |
5802 | goto unlock; |
5803 | } | |
5804 | ||
5805 | if (!atomic_inc_not_zero(&event->rb->mmap_count)) { | |
5806 | /* | |
5807 | * Raced against perf_mmap_close() through | |
5808 | * perf_event_set_output(). Try again, hope for better | |
5809 | * luck. | |
5810 | */ | |
5811 | mutex_unlock(&event->mmap_mutex); | |
5812 | goto again; | |
5813 | } | |
5814 | ||
ebb3c4c4 PZ |
5815 | goto unlock; |
5816 | } | |
5817 | ||
789f90fc | 5818 | user_extra = nr_pages + 1; |
45bfb2e5 PZ |
5819 | |
5820 | accounting: | |
cdd6c482 | 5821 | user_lock_limit = sysctl_perf_event_mlock >> (PAGE_SHIFT - 10); |
a3862d3f IM |
5822 | |
5823 | /* | |
5824 | * Increase the limit linearly with more CPUs: | |
5825 | */ | |
5826 | user_lock_limit *= num_online_cpus(); | |
5827 | ||
789f90fc | 5828 | user_locked = atomic_long_read(&user->locked_vm) + user_extra; |
c5078f78 | 5829 | |
d44248a4 SL |
5830 | if (user_locked <= user_lock_limit) { |
5831 | /* charge all to locked_vm */ | |
5832 | } else if (atomic_long_read(&user->locked_vm) >= user_lock_limit) { | |
5833 | /* charge all to pinned_vm */ | |
5834 | extra = user_extra; | |
5835 | user_extra = 0; | |
5836 | } else { | |
5837 | /* | |
5838 | * charge locked_vm until it hits user_lock_limit; | |
5839 | * charge the rest from pinned_vm | |
5840 | */ | |
789f90fc | 5841 | extra = user_locked - user_lock_limit; |
d44248a4 SL |
5842 | user_extra -= extra; |
5843 | } | |
7b732a75 | 5844 | |
78d7d407 | 5845 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
7b732a75 | 5846 | lock_limit >>= PAGE_SHIFT; |
70f8a3ca | 5847 | locked = atomic64_read(&vma->vm_mm->pinned_vm) + extra; |
7b732a75 | 5848 | |
459ec28a IM |
5849 | if ((locked > lock_limit) && perf_paranoid_tracepoint_raw() && |
5850 | !capable(CAP_IPC_LOCK)) { | |
ebb3c4c4 PZ |
5851 | ret = -EPERM; |
5852 | goto unlock; | |
5853 | } | |
7b732a75 | 5854 | |
45bfb2e5 | 5855 | WARN_ON(!rb && event->rb); |
906010b2 | 5856 | |
d57e34fd | 5857 | if (vma->vm_flags & VM_WRITE) |
76369139 | 5858 | flags |= RING_BUFFER_WRITABLE; |
d57e34fd | 5859 | |
76369139 | 5860 | if (!rb) { |
45bfb2e5 PZ |
5861 | rb = rb_alloc(nr_pages, |
5862 | event->attr.watermark ? event->attr.wakeup_watermark : 0, | |
5863 | event->cpu, flags); | |
26cb63ad | 5864 | |
45bfb2e5 PZ |
5865 | if (!rb) { |
5866 | ret = -ENOMEM; | |
5867 | goto unlock; | |
5868 | } | |
43a21ea8 | 5869 | |
45bfb2e5 PZ |
5870 | atomic_set(&rb->mmap_count, 1); |
5871 | rb->mmap_user = get_current_user(); | |
5872 | rb->mmap_locked = extra; | |
26cb63ad | 5873 | |
45bfb2e5 | 5874 | ring_buffer_attach(event, rb); |
ac9721f3 | 5875 | |
45bfb2e5 PZ |
5876 | perf_event_init_userpage(event); |
5877 | perf_event_update_userpage(event); | |
5878 | } else { | |
1a594131 AS |
5879 | ret = rb_alloc_aux(rb, event, vma->vm_pgoff, nr_pages, |
5880 | event->attr.aux_watermark, flags); | |
45bfb2e5 PZ |
5881 | if (!ret) |
5882 | rb->aux_mmap_locked = extra; | |
5883 | } | |
9a0f05cb | 5884 | |
ebb3c4c4 | 5885 | unlock: |
45bfb2e5 PZ |
5886 | if (!ret) { |
5887 | atomic_long_add(user_extra, &user->locked_vm); | |
70f8a3ca | 5888 | atomic64_add(extra, &vma->vm_mm->pinned_vm); |
45bfb2e5 | 5889 | |
ac9721f3 | 5890 | atomic_inc(&event->mmap_count); |
45bfb2e5 PZ |
5891 | } else if (rb) { |
5892 | atomic_dec(&rb->mmap_count); | |
5893 | } | |
5894 | aux_unlock: | |
cdd6c482 | 5895 | mutex_unlock(&event->mmap_mutex); |
37d81828 | 5896 | |
9bb5d40c PZ |
5897 | /* |
5898 | * Since pinned accounting is per vm we cannot allow fork() to copy our | |
5899 | * vma. | |
5900 | */ | |
26cb63ad | 5901 | vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND | VM_DONTDUMP; |
37d81828 | 5902 | vma->vm_ops = &perf_mmap_vmops; |
7b732a75 | 5903 | |
1e0fb9ec | 5904 | if (event->pmu->event_mapped) |
bfe33492 | 5905 | event->pmu->event_mapped(event, vma->vm_mm); |
1e0fb9ec | 5906 | |
7b732a75 | 5907 | return ret; |
37d81828 PM |
5908 | } |
5909 | ||
3c446b3d PZ |
5910 | static int perf_fasync(int fd, struct file *filp, int on) |
5911 | { | |
496ad9aa | 5912 | struct inode *inode = file_inode(filp); |
cdd6c482 | 5913 | struct perf_event *event = filp->private_data; |
3c446b3d PZ |
5914 | int retval; |
5915 | ||
5955102c | 5916 | inode_lock(inode); |
cdd6c482 | 5917 | retval = fasync_helper(fd, filp, on, &event->fasync); |
5955102c | 5918 | inode_unlock(inode); |
3c446b3d PZ |
5919 | |
5920 | if (retval < 0) | |
5921 | return retval; | |
5922 | ||
5923 | return 0; | |
5924 | } | |
5925 | ||
0793a61d | 5926 | static const struct file_operations perf_fops = { |
3326c1ce | 5927 | .llseek = no_llseek, |
0793a61d TG |
5928 | .release = perf_release, |
5929 | .read = perf_read, | |
5930 | .poll = perf_poll, | |
d859e29f | 5931 | .unlocked_ioctl = perf_ioctl, |
b3f20785 | 5932 | .compat_ioctl = perf_compat_ioctl, |
37d81828 | 5933 | .mmap = perf_mmap, |
3c446b3d | 5934 | .fasync = perf_fasync, |
0793a61d TG |
5935 | }; |
5936 | ||
925d519a | 5937 | /* |
cdd6c482 | 5938 | * Perf event wakeup |
925d519a PZ |
5939 | * |
5940 | * If there's data, ensure we set the poll() state and publish everything | |
5941 | * to user-space before waking everybody up. | |
5942 | */ | |
5943 | ||
fed66e2c PZ |
5944 | static inline struct fasync_struct **perf_event_fasync(struct perf_event *event) |
5945 | { | |
5946 | /* only the parent has fasync state */ | |
5947 | if (event->parent) | |
5948 | event = event->parent; | |
5949 | return &event->fasync; | |
5950 | } | |
5951 | ||
cdd6c482 | 5952 | void perf_event_wakeup(struct perf_event *event) |
925d519a | 5953 | { |
10c6db11 | 5954 | ring_buffer_wakeup(event); |
4c9e2542 | 5955 | |
cdd6c482 | 5956 | if (event->pending_kill) { |
fed66e2c | 5957 | kill_fasync(perf_event_fasync(event), SIGIO, event->pending_kill); |
cdd6c482 | 5958 | event->pending_kill = 0; |
4c9e2542 | 5959 | } |
925d519a PZ |
5960 | } |
5961 | ||
1d54ad94 PZ |
5962 | static void perf_pending_event_disable(struct perf_event *event) |
5963 | { | |
5964 | int cpu = READ_ONCE(event->pending_disable); | |
5965 | ||
5966 | if (cpu < 0) | |
5967 | return; | |
5968 | ||
5969 | if (cpu == smp_processor_id()) { | |
5970 | WRITE_ONCE(event->pending_disable, -1); | |
5971 | perf_event_disable_local(event); | |
5972 | return; | |
5973 | } | |
5974 | ||
5975 | /* | |
5976 | * CPU-A CPU-B | |
5977 | * | |
5978 | * perf_event_disable_inatomic() | |
5979 | * @pending_disable = CPU-A; | |
5980 | * irq_work_queue(); | |
5981 | * | |
5982 | * sched-out | |
5983 | * @pending_disable = -1; | |
5984 | * | |
5985 | * sched-in | |
5986 | * perf_event_disable_inatomic() | |
5987 | * @pending_disable = CPU-B; | |
5988 | * irq_work_queue(); // FAILS | |
5989 | * | |
5990 | * irq_work_run() | |
5991 | * perf_pending_event() | |
5992 | * | |
5993 | * But the event runs on CPU-B and wants disabling there. | |
5994 | */ | |
5995 | irq_work_queue_on(&event->pending, cpu); | |
5996 | } | |
5997 | ||
e360adbe | 5998 | static void perf_pending_event(struct irq_work *entry) |
79f14641 | 5999 | { |
1d54ad94 | 6000 | struct perf_event *event = container_of(entry, struct perf_event, pending); |
d525211f PZ |
6001 | int rctx; |
6002 | ||
6003 | rctx = perf_swevent_get_recursion_context(); | |
6004 | /* | |
6005 | * If we 'fail' here, that's OK, it means recursion is already disabled | |
6006 | * and we won't recurse 'further'. | |
6007 | */ | |
79f14641 | 6008 | |
1d54ad94 | 6009 | perf_pending_event_disable(event); |
79f14641 | 6010 | |
cdd6c482 IM |
6011 | if (event->pending_wakeup) { |
6012 | event->pending_wakeup = 0; | |
6013 | perf_event_wakeup(event); | |
79f14641 | 6014 | } |
d525211f PZ |
6015 | |
6016 | if (rctx >= 0) | |
6017 | perf_swevent_put_recursion_context(rctx); | |
79f14641 PZ |
6018 | } |
6019 | ||
39447b38 ZY |
6020 | /* |
6021 | * We assume there is only KVM supporting the callbacks. | |
6022 | * Later on, we might change it to a list if there is | |
6023 | * another virtualization implementation supporting the callbacks. | |
6024 | */ | |
6025 | struct perf_guest_info_callbacks *perf_guest_cbs; | |
6026 | ||
6027 | int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
6028 | { | |
6029 | perf_guest_cbs = cbs; | |
6030 | return 0; | |
6031 | } | |
6032 | EXPORT_SYMBOL_GPL(perf_register_guest_info_callbacks); | |
6033 | ||
6034 | int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
6035 | { | |
6036 | perf_guest_cbs = NULL; | |
6037 | return 0; | |
6038 | } | |
6039 | EXPORT_SYMBOL_GPL(perf_unregister_guest_info_callbacks); | |
6040 | ||
4018994f JO |
6041 | static void |
6042 | perf_output_sample_regs(struct perf_output_handle *handle, | |
6043 | struct pt_regs *regs, u64 mask) | |
6044 | { | |
6045 | int bit; | |
29dd3288 | 6046 | DECLARE_BITMAP(_mask, 64); |
4018994f | 6047 | |
29dd3288 MS |
6048 | bitmap_from_u64(_mask, mask); |
6049 | for_each_set_bit(bit, _mask, sizeof(mask) * BITS_PER_BYTE) { | |
4018994f JO |
6050 | u64 val; |
6051 | ||
6052 | val = perf_reg_value(regs, bit); | |
6053 | perf_output_put(handle, val); | |
6054 | } | |
6055 | } | |
6056 | ||
60e2364e | 6057 | static void perf_sample_regs_user(struct perf_regs *regs_user, |
88a7c26a AL |
6058 | struct pt_regs *regs, |
6059 | struct pt_regs *regs_user_copy) | |
4018994f | 6060 | { |
88a7c26a AL |
6061 | if (user_mode(regs)) { |
6062 | regs_user->abi = perf_reg_abi(current); | |
2565711f | 6063 | regs_user->regs = regs; |
085ebfe9 | 6064 | } else if (!(current->flags & PF_KTHREAD)) { |
88a7c26a | 6065 | perf_get_regs_user(regs_user, regs, regs_user_copy); |
2565711f PZ |
6066 | } else { |
6067 | regs_user->abi = PERF_SAMPLE_REGS_ABI_NONE; | |
6068 | regs_user->regs = NULL; | |
4018994f JO |
6069 | } |
6070 | } | |
6071 | ||
60e2364e SE |
6072 | static void perf_sample_regs_intr(struct perf_regs *regs_intr, |
6073 | struct pt_regs *regs) | |
6074 | { | |
6075 | regs_intr->regs = regs; | |
6076 | regs_intr->abi = perf_reg_abi(current); | |
6077 | } | |
6078 | ||
6079 | ||
c5ebcedb JO |
6080 | /* |
6081 | * Get remaining task size from user stack pointer. | |
6082 | * | |
6083 | * It'd be better to take stack vma map and limit this more | |
9f014e3a | 6084 | * precisely, but there's no way to get it safely under interrupt, |
c5ebcedb JO |
6085 | * so using TASK_SIZE as limit. |
6086 | */ | |
6087 | static u64 perf_ustack_task_size(struct pt_regs *regs) | |
6088 | { | |
6089 | unsigned long addr = perf_user_stack_pointer(regs); | |
6090 | ||
6091 | if (!addr || addr >= TASK_SIZE) | |
6092 | return 0; | |
6093 | ||
6094 | return TASK_SIZE - addr; | |
6095 | } | |
6096 | ||
6097 | static u16 | |
6098 | perf_sample_ustack_size(u16 stack_size, u16 header_size, | |
6099 | struct pt_regs *regs) | |
6100 | { | |
6101 | u64 task_size; | |
6102 | ||
6103 | /* No regs, no stack pointer, no dump. */ | |
6104 | if (!regs) | |
6105 | return 0; | |
6106 | ||
6107 | /* | |
6108 | * Check if we fit in with the requested stack size into the: | |
6109 | * - TASK_SIZE | |
6110 | * If we don't, we limit the size to the TASK_SIZE. | |
6111 | * | |
6112 | * - remaining sample size | |
6113 | * If we don't, we customize the stack size to | |
6114 | * fit in to the remaining sample size. | |
6115 | */ | |
6116 | ||
6117 | task_size = min((u64) USHRT_MAX, perf_ustack_task_size(regs)); | |
6118 | stack_size = min(stack_size, (u16) task_size); | |
6119 | ||
6120 | /* Current header size plus static size and dynamic size. */ | |
6121 | header_size += 2 * sizeof(u64); | |
6122 | ||
6123 | /* Do we fit in with the current stack dump size? */ | |
6124 | if ((u16) (header_size + stack_size) < header_size) { | |
6125 | /* | |
6126 | * If we overflow the maximum size for the sample, | |
6127 | * we customize the stack dump size to fit in. | |
6128 | */ | |
6129 | stack_size = USHRT_MAX - header_size - sizeof(u64); | |
6130 | stack_size = round_up(stack_size, sizeof(u64)); | |
6131 | } | |
6132 | ||
6133 | return stack_size; | |
6134 | } | |
6135 | ||
6136 | static void | |
6137 | perf_output_sample_ustack(struct perf_output_handle *handle, u64 dump_size, | |
6138 | struct pt_regs *regs) | |
6139 | { | |
6140 | /* Case of a kernel thread, nothing to dump */ | |
6141 | if (!regs) { | |
6142 | u64 size = 0; | |
6143 | perf_output_put(handle, size); | |
6144 | } else { | |
6145 | unsigned long sp; | |
6146 | unsigned int rem; | |
6147 | u64 dyn_size; | |
02e18447 | 6148 | mm_segment_t fs; |
c5ebcedb JO |
6149 | |
6150 | /* | |
6151 | * We dump: | |
6152 | * static size | |
6153 | * - the size requested by user or the best one we can fit | |
6154 | * in to the sample max size | |
6155 | * data | |
6156 | * - user stack dump data | |
6157 | * dynamic size | |
6158 | * - the actual dumped size | |
6159 | */ | |
6160 | ||
6161 | /* Static size. */ | |
6162 | perf_output_put(handle, dump_size); | |
6163 | ||
6164 | /* Data. */ | |
6165 | sp = perf_user_stack_pointer(regs); | |
02e18447 YC |
6166 | fs = get_fs(); |
6167 | set_fs(USER_DS); | |
c5ebcedb | 6168 | rem = __output_copy_user(handle, (void *) sp, dump_size); |
02e18447 | 6169 | set_fs(fs); |
c5ebcedb JO |
6170 | dyn_size = dump_size - rem; |
6171 | ||
6172 | perf_output_skip(handle, rem); | |
6173 | ||
6174 | /* Dynamic size. */ | |
6175 | perf_output_put(handle, dyn_size); | |
6176 | } | |
6177 | } | |
6178 | ||
c980d109 ACM |
6179 | static void __perf_event_header__init_id(struct perf_event_header *header, |
6180 | struct perf_sample_data *data, | |
6181 | struct perf_event *event) | |
6844c09d ACM |
6182 | { |
6183 | u64 sample_type = event->attr.sample_type; | |
6184 | ||
6185 | data->type = sample_type; | |
6186 | header->size += event->id_header_size; | |
6187 | ||
6188 | if (sample_type & PERF_SAMPLE_TID) { | |
6189 | /* namespace issues */ | |
6190 | data->tid_entry.pid = perf_event_pid(event, current); | |
6191 | data->tid_entry.tid = perf_event_tid(event, current); | |
6192 | } | |
6193 | ||
6194 | if (sample_type & PERF_SAMPLE_TIME) | |
34f43927 | 6195 | data->time = perf_event_clock(event); |
6844c09d | 6196 | |
ff3d527c | 6197 | if (sample_type & (PERF_SAMPLE_ID | PERF_SAMPLE_IDENTIFIER)) |
6844c09d ACM |
6198 | data->id = primary_event_id(event); |
6199 | ||
6200 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6201 | data->stream_id = event->id; | |
6202 | ||
6203 | if (sample_type & PERF_SAMPLE_CPU) { | |
6204 | data->cpu_entry.cpu = raw_smp_processor_id(); | |
6205 | data->cpu_entry.reserved = 0; | |
6206 | } | |
6207 | } | |
6208 | ||
76369139 FW |
6209 | void perf_event_header__init_id(struct perf_event_header *header, |
6210 | struct perf_sample_data *data, | |
6211 | struct perf_event *event) | |
c980d109 ACM |
6212 | { |
6213 | if (event->attr.sample_id_all) | |
6214 | __perf_event_header__init_id(header, data, event); | |
6215 | } | |
6216 | ||
6217 | static void __perf_event__output_id_sample(struct perf_output_handle *handle, | |
6218 | struct perf_sample_data *data) | |
6219 | { | |
6220 | u64 sample_type = data->type; | |
6221 | ||
6222 | if (sample_type & PERF_SAMPLE_TID) | |
6223 | perf_output_put(handle, data->tid_entry); | |
6224 | ||
6225 | if (sample_type & PERF_SAMPLE_TIME) | |
6226 | perf_output_put(handle, data->time); | |
6227 | ||
6228 | if (sample_type & PERF_SAMPLE_ID) | |
6229 | perf_output_put(handle, data->id); | |
6230 | ||
6231 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6232 | perf_output_put(handle, data->stream_id); | |
6233 | ||
6234 | if (sample_type & PERF_SAMPLE_CPU) | |
6235 | perf_output_put(handle, data->cpu_entry); | |
ff3d527c AH |
6236 | |
6237 | if (sample_type & PERF_SAMPLE_IDENTIFIER) | |
6238 | perf_output_put(handle, data->id); | |
c980d109 ACM |
6239 | } |
6240 | ||
76369139 FW |
6241 | void perf_event__output_id_sample(struct perf_event *event, |
6242 | struct perf_output_handle *handle, | |
6243 | struct perf_sample_data *sample) | |
c980d109 ACM |
6244 | { |
6245 | if (event->attr.sample_id_all) | |
6246 | __perf_event__output_id_sample(handle, sample); | |
6247 | } | |
6248 | ||
3dab77fb | 6249 | static void perf_output_read_one(struct perf_output_handle *handle, |
eed01528 SE |
6250 | struct perf_event *event, |
6251 | u64 enabled, u64 running) | |
3dab77fb | 6252 | { |
cdd6c482 | 6253 | u64 read_format = event->attr.read_format; |
3dab77fb PZ |
6254 | u64 values[4]; |
6255 | int n = 0; | |
6256 | ||
b5e58793 | 6257 | values[n++] = perf_event_count(event); |
3dab77fb | 6258 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { |
eed01528 | 6259 | values[n++] = enabled + |
cdd6c482 | 6260 | atomic64_read(&event->child_total_time_enabled); |
3dab77fb PZ |
6261 | } |
6262 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { | |
eed01528 | 6263 | values[n++] = running + |
cdd6c482 | 6264 | atomic64_read(&event->child_total_time_running); |
3dab77fb PZ |
6265 | } |
6266 | if (read_format & PERF_FORMAT_ID) | |
cdd6c482 | 6267 | values[n++] = primary_event_id(event); |
3dab77fb | 6268 | |
76369139 | 6269 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
6270 | } |
6271 | ||
3dab77fb | 6272 | static void perf_output_read_group(struct perf_output_handle *handle, |
eed01528 SE |
6273 | struct perf_event *event, |
6274 | u64 enabled, u64 running) | |
3dab77fb | 6275 | { |
cdd6c482 IM |
6276 | struct perf_event *leader = event->group_leader, *sub; |
6277 | u64 read_format = event->attr.read_format; | |
3dab77fb PZ |
6278 | u64 values[5]; |
6279 | int n = 0; | |
6280 | ||
6281 | values[n++] = 1 + leader->nr_siblings; | |
6282 | ||
6283 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
eed01528 | 6284 | values[n++] = enabled; |
3dab77fb PZ |
6285 | |
6286 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
eed01528 | 6287 | values[n++] = running; |
3dab77fb | 6288 | |
9e5b127d PZ |
6289 | if ((leader != event) && |
6290 | (leader->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
6291 | leader->pmu->read(leader); |
6292 | ||
b5e58793 | 6293 | values[n++] = perf_event_count(leader); |
3dab77fb | 6294 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 6295 | values[n++] = primary_event_id(leader); |
3dab77fb | 6296 | |
76369139 | 6297 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb | 6298 | |
edb39592 | 6299 | for_each_sibling_event(sub, leader) { |
3dab77fb PZ |
6300 | n = 0; |
6301 | ||
6f5ab001 JO |
6302 | if ((sub != event) && |
6303 | (sub->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
6304 | sub->pmu->read(sub); |
6305 | ||
b5e58793 | 6306 | values[n++] = perf_event_count(sub); |
3dab77fb | 6307 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 6308 | values[n++] = primary_event_id(sub); |
3dab77fb | 6309 | |
76369139 | 6310 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
6311 | } |
6312 | } | |
6313 | ||
eed01528 SE |
6314 | #define PERF_FORMAT_TOTAL_TIMES (PERF_FORMAT_TOTAL_TIME_ENABLED|\ |
6315 | PERF_FORMAT_TOTAL_TIME_RUNNING) | |
6316 | ||
ba5213ae PZ |
6317 | /* |
6318 | * XXX PERF_SAMPLE_READ vs inherited events seems difficult. | |
6319 | * | |
6320 | * The problem is that its both hard and excessively expensive to iterate the | |
6321 | * child list, not to mention that its impossible to IPI the children running | |
6322 | * on another CPU, from interrupt/NMI context. | |
6323 | */ | |
3dab77fb | 6324 | static void perf_output_read(struct perf_output_handle *handle, |
cdd6c482 | 6325 | struct perf_event *event) |
3dab77fb | 6326 | { |
e3f3541c | 6327 | u64 enabled = 0, running = 0, now; |
eed01528 SE |
6328 | u64 read_format = event->attr.read_format; |
6329 | ||
6330 | /* | |
6331 | * compute total_time_enabled, total_time_running | |
6332 | * based on snapshot values taken when the event | |
6333 | * was last scheduled in. | |
6334 | * | |
6335 | * we cannot simply called update_context_time() | |
6336 | * because of locking issue as we are called in | |
6337 | * NMI context | |
6338 | */ | |
c4794295 | 6339 | if (read_format & PERF_FORMAT_TOTAL_TIMES) |
e3f3541c | 6340 | calc_timer_values(event, &now, &enabled, &running); |
eed01528 | 6341 | |
cdd6c482 | 6342 | if (event->attr.read_format & PERF_FORMAT_GROUP) |
eed01528 | 6343 | perf_output_read_group(handle, event, enabled, running); |
3dab77fb | 6344 | else |
eed01528 | 6345 | perf_output_read_one(handle, event, enabled, running); |
3dab77fb PZ |
6346 | } |
6347 | ||
5622f295 MM |
6348 | void perf_output_sample(struct perf_output_handle *handle, |
6349 | struct perf_event_header *header, | |
6350 | struct perf_sample_data *data, | |
cdd6c482 | 6351 | struct perf_event *event) |
5622f295 MM |
6352 | { |
6353 | u64 sample_type = data->type; | |
6354 | ||
6355 | perf_output_put(handle, *header); | |
6356 | ||
ff3d527c AH |
6357 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
6358 | perf_output_put(handle, data->id); | |
6359 | ||
5622f295 MM |
6360 | if (sample_type & PERF_SAMPLE_IP) |
6361 | perf_output_put(handle, data->ip); | |
6362 | ||
6363 | if (sample_type & PERF_SAMPLE_TID) | |
6364 | perf_output_put(handle, data->tid_entry); | |
6365 | ||
6366 | if (sample_type & PERF_SAMPLE_TIME) | |
6367 | perf_output_put(handle, data->time); | |
6368 | ||
6369 | if (sample_type & PERF_SAMPLE_ADDR) | |
6370 | perf_output_put(handle, data->addr); | |
6371 | ||
6372 | if (sample_type & PERF_SAMPLE_ID) | |
6373 | perf_output_put(handle, data->id); | |
6374 | ||
6375 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6376 | perf_output_put(handle, data->stream_id); | |
6377 | ||
6378 | if (sample_type & PERF_SAMPLE_CPU) | |
6379 | perf_output_put(handle, data->cpu_entry); | |
6380 | ||
6381 | if (sample_type & PERF_SAMPLE_PERIOD) | |
6382 | perf_output_put(handle, data->period); | |
6383 | ||
6384 | if (sample_type & PERF_SAMPLE_READ) | |
cdd6c482 | 6385 | perf_output_read(handle, event); |
5622f295 MM |
6386 | |
6387 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { | |
99e818cc | 6388 | int size = 1; |
5622f295 | 6389 | |
99e818cc JO |
6390 | size += data->callchain->nr; |
6391 | size *= sizeof(u64); | |
6392 | __output_copy(handle, data->callchain, size); | |
5622f295 MM |
6393 | } |
6394 | ||
6395 | if (sample_type & PERF_SAMPLE_RAW) { | |
7e3f977e DB |
6396 | struct perf_raw_record *raw = data->raw; |
6397 | ||
6398 | if (raw) { | |
6399 | struct perf_raw_frag *frag = &raw->frag; | |
6400 | ||
6401 | perf_output_put(handle, raw->size); | |
6402 | do { | |
6403 | if (frag->copy) { | |
6404 | __output_custom(handle, frag->copy, | |
6405 | frag->data, frag->size); | |
6406 | } else { | |
6407 | __output_copy(handle, frag->data, | |
6408 | frag->size); | |
6409 | } | |
6410 | if (perf_raw_frag_last(frag)) | |
6411 | break; | |
6412 | frag = frag->next; | |
6413 | } while (1); | |
6414 | if (frag->pad) | |
6415 | __output_skip(handle, NULL, frag->pad); | |
5622f295 MM |
6416 | } else { |
6417 | struct { | |
6418 | u32 size; | |
6419 | u32 data; | |
6420 | } raw = { | |
6421 | .size = sizeof(u32), | |
6422 | .data = 0, | |
6423 | }; | |
6424 | perf_output_put(handle, raw); | |
6425 | } | |
6426 | } | |
a7ac67ea | 6427 | |
bce38cd5 SE |
6428 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { |
6429 | if (data->br_stack) { | |
6430 | size_t size; | |
6431 | ||
6432 | size = data->br_stack->nr | |
6433 | * sizeof(struct perf_branch_entry); | |
6434 | ||
6435 | perf_output_put(handle, data->br_stack->nr); | |
6436 | perf_output_copy(handle, data->br_stack->entries, size); | |
6437 | } else { | |
6438 | /* | |
6439 | * we always store at least the value of nr | |
6440 | */ | |
6441 | u64 nr = 0; | |
6442 | perf_output_put(handle, nr); | |
6443 | } | |
6444 | } | |
4018994f JO |
6445 | |
6446 | if (sample_type & PERF_SAMPLE_REGS_USER) { | |
6447 | u64 abi = data->regs_user.abi; | |
6448 | ||
6449 | /* | |
6450 | * If there are no regs to dump, notice it through | |
6451 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
6452 | */ | |
6453 | perf_output_put(handle, abi); | |
6454 | ||
6455 | if (abi) { | |
6456 | u64 mask = event->attr.sample_regs_user; | |
6457 | perf_output_sample_regs(handle, | |
6458 | data->regs_user.regs, | |
6459 | mask); | |
6460 | } | |
6461 | } | |
c5ebcedb | 6462 | |
a5cdd40c | 6463 | if (sample_type & PERF_SAMPLE_STACK_USER) { |
c5ebcedb JO |
6464 | perf_output_sample_ustack(handle, |
6465 | data->stack_user_size, | |
6466 | data->regs_user.regs); | |
a5cdd40c | 6467 | } |
c3feedf2 AK |
6468 | |
6469 | if (sample_type & PERF_SAMPLE_WEIGHT) | |
6470 | perf_output_put(handle, data->weight); | |
d6be9ad6 SE |
6471 | |
6472 | if (sample_type & PERF_SAMPLE_DATA_SRC) | |
6473 | perf_output_put(handle, data->data_src.val); | |
a5cdd40c | 6474 | |
fdfbbd07 AK |
6475 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
6476 | perf_output_put(handle, data->txn); | |
6477 | ||
60e2364e SE |
6478 | if (sample_type & PERF_SAMPLE_REGS_INTR) { |
6479 | u64 abi = data->regs_intr.abi; | |
6480 | /* | |
6481 | * If there are no regs to dump, notice it through | |
6482 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
6483 | */ | |
6484 | perf_output_put(handle, abi); | |
6485 | ||
6486 | if (abi) { | |
6487 | u64 mask = event->attr.sample_regs_intr; | |
6488 | ||
6489 | perf_output_sample_regs(handle, | |
6490 | data->regs_intr.regs, | |
6491 | mask); | |
6492 | } | |
6493 | } | |
6494 | ||
fc7ce9c7 KL |
6495 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) |
6496 | perf_output_put(handle, data->phys_addr); | |
6497 | ||
a5cdd40c PZ |
6498 | if (!event->attr.watermark) { |
6499 | int wakeup_events = event->attr.wakeup_events; | |
6500 | ||
6501 | if (wakeup_events) { | |
6502 | struct ring_buffer *rb = handle->rb; | |
6503 | int events = local_inc_return(&rb->events); | |
6504 | ||
6505 | if (events >= wakeup_events) { | |
6506 | local_sub(wakeup_events, &rb->events); | |
6507 | local_inc(&rb->wakeup); | |
6508 | } | |
6509 | } | |
6510 | } | |
5622f295 MM |
6511 | } |
6512 | ||
fc7ce9c7 KL |
6513 | static u64 perf_virt_to_phys(u64 virt) |
6514 | { | |
6515 | u64 phys_addr = 0; | |
6516 | struct page *p = NULL; | |
6517 | ||
6518 | if (!virt) | |
6519 | return 0; | |
6520 | ||
6521 | if (virt >= TASK_SIZE) { | |
6522 | /* If it's vmalloc()d memory, leave phys_addr as 0 */ | |
6523 | if (virt_addr_valid((void *)(uintptr_t)virt) && | |
6524 | !(virt >= VMALLOC_START && virt < VMALLOC_END)) | |
6525 | phys_addr = (u64)virt_to_phys((void *)(uintptr_t)virt); | |
6526 | } else { | |
6527 | /* | |
6528 | * Walking the pages tables for user address. | |
6529 | * Interrupts are disabled, so it prevents any tear down | |
6530 | * of the page tables. | |
6531 | * Try IRQ-safe __get_user_pages_fast first. | |
6532 | * If failed, leave phys_addr as 0. | |
6533 | */ | |
6534 | if ((current->mm != NULL) && | |
6535 | (__get_user_pages_fast(virt, 1, 0, &p) == 1)) | |
6536 | phys_addr = page_to_phys(p) + virt % PAGE_SIZE; | |
6537 | ||
6538 | if (p) | |
6539 | put_page(p); | |
6540 | } | |
6541 | ||
6542 | return phys_addr; | |
6543 | } | |
6544 | ||
99e818cc JO |
6545 | static struct perf_callchain_entry __empty_callchain = { .nr = 0, }; |
6546 | ||
6cbc304f | 6547 | struct perf_callchain_entry * |
8cf7e0e2 JO |
6548 | perf_callchain(struct perf_event *event, struct pt_regs *regs) |
6549 | { | |
6550 | bool kernel = !event->attr.exclude_callchain_kernel; | |
6551 | bool user = !event->attr.exclude_callchain_user; | |
6552 | /* Disallow cross-task user callchains. */ | |
6553 | bool crosstask = event->ctx->task && event->ctx->task != current; | |
6554 | const u32 max_stack = event->attr.sample_max_stack; | |
99e818cc | 6555 | struct perf_callchain_entry *callchain; |
8cf7e0e2 JO |
6556 | |
6557 | if (!kernel && !user) | |
99e818cc | 6558 | return &__empty_callchain; |
8cf7e0e2 | 6559 | |
99e818cc JO |
6560 | callchain = get_perf_callchain(regs, 0, kernel, user, |
6561 | max_stack, crosstask, true); | |
6562 | return callchain ?: &__empty_callchain; | |
8cf7e0e2 JO |
6563 | } |
6564 | ||
5622f295 MM |
6565 | void perf_prepare_sample(struct perf_event_header *header, |
6566 | struct perf_sample_data *data, | |
cdd6c482 | 6567 | struct perf_event *event, |
5622f295 | 6568 | struct pt_regs *regs) |
7b732a75 | 6569 | { |
cdd6c482 | 6570 | u64 sample_type = event->attr.sample_type; |
7b732a75 | 6571 | |
cdd6c482 | 6572 | header->type = PERF_RECORD_SAMPLE; |
c320c7b7 | 6573 | header->size = sizeof(*header) + event->header_size; |
5622f295 MM |
6574 | |
6575 | header->misc = 0; | |
6576 | header->misc |= perf_misc_flags(regs); | |
6fab0192 | 6577 | |
c980d109 | 6578 | __perf_event_header__init_id(header, data, event); |
6844c09d | 6579 | |
c320c7b7 | 6580 | if (sample_type & PERF_SAMPLE_IP) |
5622f295 MM |
6581 | data->ip = perf_instruction_pointer(regs); |
6582 | ||
b23f3325 | 6583 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { |
5622f295 | 6584 | int size = 1; |
394ee076 | 6585 | |
6cbc304f PZ |
6586 | if (!(sample_type & __PERF_SAMPLE_CALLCHAIN_EARLY)) |
6587 | data->callchain = perf_callchain(event, regs); | |
6588 | ||
99e818cc | 6589 | size += data->callchain->nr; |
5622f295 MM |
6590 | |
6591 | header->size += size * sizeof(u64); | |
394ee076 PZ |
6592 | } |
6593 | ||
3a43ce68 | 6594 | if (sample_type & PERF_SAMPLE_RAW) { |
7e3f977e DB |
6595 | struct perf_raw_record *raw = data->raw; |
6596 | int size; | |
6597 | ||
6598 | if (raw) { | |
6599 | struct perf_raw_frag *frag = &raw->frag; | |
6600 | u32 sum = 0; | |
6601 | ||
6602 | do { | |
6603 | sum += frag->size; | |
6604 | if (perf_raw_frag_last(frag)) | |
6605 | break; | |
6606 | frag = frag->next; | |
6607 | } while (1); | |
6608 | ||
6609 | size = round_up(sum + sizeof(u32), sizeof(u64)); | |
6610 | raw->size = size - sizeof(u32); | |
6611 | frag->pad = raw->size - sum; | |
6612 | } else { | |
6613 | size = sizeof(u64); | |
6614 | } | |
a044560c | 6615 | |
7e3f977e | 6616 | header->size += size; |
7f453c24 | 6617 | } |
bce38cd5 SE |
6618 | |
6619 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { | |
6620 | int size = sizeof(u64); /* nr */ | |
6621 | if (data->br_stack) { | |
6622 | size += data->br_stack->nr | |
6623 | * sizeof(struct perf_branch_entry); | |
6624 | } | |
6625 | header->size += size; | |
6626 | } | |
4018994f | 6627 | |
2565711f | 6628 | if (sample_type & (PERF_SAMPLE_REGS_USER | PERF_SAMPLE_STACK_USER)) |
88a7c26a AL |
6629 | perf_sample_regs_user(&data->regs_user, regs, |
6630 | &data->regs_user_copy); | |
2565711f | 6631 | |
4018994f JO |
6632 | if (sample_type & PERF_SAMPLE_REGS_USER) { |
6633 | /* regs dump ABI info */ | |
6634 | int size = sizeof(u64); | |
6635 | ||
4018994f JO |
6636 | if (data->regs_user.regs) { |
6637 | u64 mask = event->attr.sample_regs_user; | |
6638 | size += hweight64(mask) * sizeof(u64); | |
6639 | } | |
6640 | ||
6641 | header->size += size; | |
6642 | } | |
c5ebcedb JO |
6643 | |
6644 | if (sample_type & PERF_SAMPLE_STACK_USER) { | |
6645 | /* | |
9f014e3a | 6646 | * Either we need PERF_SAMPLE_STACK_USER bit to be always |
c5ebcedb JO |
6647 | * processed as the last one or have additional check added |
6648 | * in case new sample type is added, because we could eat | |
6649 | * up the rest of the sample size. | |
6650 | */ | |
c5ebcedb JO |
6651 | u16 stack_size = event->attr.sample_stack_user; |
6652 | u16 size = sizeof(u64); | |
6653 | ||
c5ebcedb | 6654 | stack_size = perf_sample_ustack_size(stack_size, header->size, |
2565711f | 6655 | data->regs_user.regs); |
c5ebcedb JO |
6656 | |
6657 | /* | |
6658 | * If there is something to dump, add space for the dump | |
6659 | * itself and for the field that tells the dynamic size, | |
6660 | * which is how many have been actually dumped. | |
6661 | */ | |
6662 | if (stack_size) | |
6663 | size += sizeof(u64) + stack_size; | |
6664 | ||
6665 | data->stack_user_size = stack_size; | |
6666 | header->size += size; | |
6667 | } | |
60e2364e SE |
6668 | |
6669 | if (sample_type & PERF_SAMPLE_REGS_INTR) { | |
6670 | /* regs dump ABI info */ | |
6671 | int size = sizeof(u64); | |
6672 | ||
6673 | perf_sample_regs_intr(&data->regs_intr, regs); | |
6674 | ||
6675 | if (data->regs_intr.regs) { | |
6676 | u64 mask = event->attr.sample_regs_intr; | |
6677 | ||
6678 | size += hweight64(mask) * sizeof(u64); | |
6679 | } | |
6680 | ||
6681 | header->size += size; | |
6682 | } | |
fc7ce9c7 KL |
6683 | |
6684 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) | |
6685 | data->phys_addr = perf_virt_to_phys(data->addr); | |
5622f295 | 6686 | } |
7f453c24 | 6687 | |
56201969 | 6688 | static __always_inline int |
9ecda41a WN |
6689 | __perf_event_output(struct perf_event *event, |
6690 | struct perf_sample_data *data, | |
6691 | struct pt_regs *regs, | |
6692 | int (*output_begin)(struct perf_output_handle *, | |
6693 | struct perf_event *, | |
6694 | unsigned int)) | |
5622f295 MM |
6695 | { |
6696 | struct perf_output_handle handle; | |
6697 | struct perf_event_header header; | |
56201969 | 6698 | int err; |
689802b2 | 6699 | |
927c7a9e FW |
6700 | /* protect the callchain buffers */ |
6701 | rcu_read_lock(); | |
6702 | ||
cdd6c482 | 6703 | perf_prepare_sample(&header, data, event, regs); |
5c148194 | 6704 | |
56201969 ACM |
6705 | err = output_begin(&handle, event, header.size); |
6706 | if (err) | |
927c7a9e | 6707 | goto exit; |
0322cd6e | 6708 | |
cdd6c482 | 6709 | perf_output_sample(&handle, &header, data, event); |
f413cdb8 | 6710 | |
8a057d84 | 6711 | perf_output_end(&handle); |
927c7a9e FW |
6712 | |
6713 | exit: | |
6714 | rcu_read_unlock(); | |
56201969 | 6715 | return err; |
0322cd6e PZ |
6716 | } |
6717 | ||
9ecda41a WN |
6718 | void |
6719 | perf_event_output_forward(struct perf_event *event, | |
6720 | struct perf_sample_data *data, | |
6721 | struct pt_regs *regs) | |
6722 | { | |
6723 | __perf_event_output(event, data, regs, perf_output_begin_forward); | |
6724 | } | |
6725 | ||
6726 | void | |
6727 | perf_event_output_backward(struct perf_event *event, | |
6728 | struct perf_sample_data *data, | |
6729 | struct pt_regs *regs) | |
6730 | { | |
6731 | __perf_event_output(event, data, regs, perf_output_begin_backward); | |
6732 | } | |
6733 | ||
56201969 | 6734 | int |
9ecda41a WN |
6735 | perf_event_output(struct perf_event *event, |
6736 | struct perf_sample_data *data, | |
6737 | struct pt_regs *regs) | |
6738 | { | |
56201969 | 6739 | return __perf_event_output(event, data, regs, perf_output_begin); |
9ecda41a WN |
6740 | } |
6741 | ||
38b200d6 | 6742 | /* |
cdd6c482 | 6743 | * read event_id |
38b200d6 PZ |
6744 | */ |
6745 | ||
6746 | struct perf_read_event { | |
6747 | struct perf_event_header header; | |
6748 | ||
6749 | u32 pid; | |
6750 | u32 tid; | |
38b200d6 PZ |
6751 | }; |
6752 | ||
6753 | static void | |
cdd6c482 | 6754 | perf_event_read_event(struct perf_event *event, |
38b200d6 PZ |
6755 | struct task_struct *task) |
6756 | { | |
6757 | struct perf_output_handle handle; | |
c980d109 | 6758 | struct perf_sample_data sample; |
dfc65094 | 6759 | struct perf_read_event read_event = { |
38b200d6 | 6760 | .header = { |
cdd6c482 | 6761 | .type = PERF_RECORD_READ, |
38b200d6 | 6762 | .misc = 0, |
c320c7b7 | 6763 | .size = sizeof(read_event) + event->read_size, |
38b200d6 | 6764 | }, |
cdd6c482 IM |
6765 | .pid = perf_event_pid(event, task), |
6766 | .tid = perf_event_tid(event, task), | |
38b200d6 | 6767 | }; |
3dab77fb | 6768 | int ret; |
38b200d6 | 6769 | |
c980d109 | 6770 | perf_event_header__init_id(&read_event.header, &sample, event); |
a7ac67ea | 6771 | ret = perf_output_begin(&handle, event, read_event.header.size); |
38b200d6 PZ |
6772 | if (ret) |
6773 | return; | |
6774 | ||
dfc65094 | 6775 | perf_output_put(&handle, read_event); |
cdd6c482 | 6776 | perf_output_read(&handle, event); |
c980d109 | 6777 | perf_event__output_id_sample(event, &handle, &sample); |
3dab77fb | 6778 | |
38b200d6 PZ |
6779 | perf_output_end(&handle); |
6780 | } | |
6781 | ||
aab5b71e | 6782 | typedef void (perf_iterate_f)(struct perf_event *event, void *data); |
52d857a8 JO |
6783 | |
6784 | static void | |
aab5b71e PZ |
6785 | perf_iterate_ctx(struct perf_event_context *ctx, |
6786 | perf_iterate_f output, | |
b73e4fef | 6787 | void *data, bool all) |
52d857a8 JO |
6788 | { |
6789 | struct perf_event *event; | |
6790 | ||
6791 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
b73e4fef AS |
6792 | if (!all) { |
6793 | if (event->state < PERF_EVENT_STATE_INACTIVE) | |
6794 | continue; | |
6795 | if (!event_filter_match(event)) | |
6796 | continue; | |
6797 | } | |
6798 | ||
67516844 | 6799 | output(event, data); |
52d857a8 JO |
6800 | } |
6801 | } | |
6802 | ||
aab5b71e | 6803 | static void perf_iterate_sb_cpu(perf_iterate_f output, void *data) |
f2fb6bef KL |
6804 | { |
6805 | struct pmu_event_list *pel = this_cpu_ptr(&pmu_sb_events); | |
6806 | struct perf_event *event; | |
6807 | ||
6808 | list_for_each_entry_rcu(event, &pel->list, sb_list) { | |
0b8f1e2e PZ |
6809 | /* |
6810 | * Skip events that are not fully formed yet; ensure that | |
6811 | * if we observe event->ctx, both event and ctx will be | |
6812 | * complete enough. See perf_install_in_context(). | |
6813 | */ | |
6814 | if (!smp_load_acquire(&event->ctx)) | |
6815 | continue; | |
6816 | ||
f2fb6bef KL |
6817 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
6818 | continue; | |
6819 | if (!event_filter_match(event)) | |
6820 | continue; | |
6821 | output(event, data); | |
6822 | } | |
6823 | } | |
6824 | ||
aab5b71e PZ |
6825 | /* |
6826 | * Iterate all events that need to receive side-band events. | |
6827 | * | |
6828 | * For new callers; ensure that account_pmu_sb_event() includes | |
6829 | * your event, otherwise it might not get delivered. | |
6830 | */ | |
52d857a8 | 6831 | static void |
aab5b71e | 6832 | perf_iterate_sb(perf_iterate_f output, void *data, |
52d857a8 JO |
6833 | struct perf_event_context *task_ctx) |
6834 | { | |
52d857a8 | 6835 | struct perf_event_context *ctx; |
52d857a8 JO |
6836 | int ctxn; |
6837 | ||
aab5b71e PZ |
6838 | rcu_read_lock(); |
6839 | preempt_disable(); | |
6840 | ||
4e93ad60 | 6841 | /* |
aab5b71e PZ |
6842 | * If we have task_ctx != NULL we only notify the task context itself. |
6843 | * The task_ctx is set only for EXIT events before releasing task | |
4e93ad60 JO |
6844 | * context. |
6845 | */ | |
6846 | if (task_ctx) { | |
aab5b71e PZ |
6847 | perf_iterate_ctx(task_ctx, output, data, false); |
6848 | goto done; | |
4e93ad60 JO |
6849 | } |
6850 | ||
aab5b71e | 6851 | perf_iterate_sb_cpu(output, data); |
f2fb6bef KL |
6852 | |
6853 | for_each_task_context_nr(ctxn) { | |
52d857a8 JO |
6854 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); |
6855 | if (ctx) | |
aab5b71e | 6856 | perf_iterate_ctx(ctx, output, data, false); |
52d857a8 | 6857 | } |
aab5b71e | 6858 | done: |
f2fb6bef | 6859 | preempt_enable(); |
52d857a8 | 6860 | rcu_read_unlock(); |
95ff4ca2 AS |
6861 | } |
6862 | ||
375637bc AS |
6863 | /* |
6864 | * Clear all file-based filters at exec, they'll have to be | |
6865 | * re-instated when/if these objects are mmapped again. | |
6866 | */ | |
6867 | static void perf_event_addr_filters_exec(struct perf_event *event, void *data) | |
6868 | { | |
6869 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
6870 | struct perf_addr_filter *filter; | |
6871 | unsigned int restart = 0, count = 0; | |
6872 | unsigned long flags; | |
6873 | ||
6874 | if (!has_addr_filter(event)) | |
6875 | return; | |
6876 | ||
6877 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
6878 | list_for_each_entry(filter, &ifh->list, entry) { | |
9511bce9 | 6879 | if (filter->path.dentry) { |
c60f83b8 AS |
6880 | event->addr_filter_ranges[count].start = 0; |
6881 | event->addr_filter_ranges[count].size = 0; | |
375637bc AS |
6882 | restart++; |
6883 | } | |
6884 | ||
6885 | count++; | |
6886 | } | |
6887 | ||
6888 | if (restart) | |
6889 | event->addr_filters_gen++; | |
6890 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
6891 | ||
6892 | if (restart) | |
767ae086 | 6893 | perf_event_stop(event, 1); |
375637bc AS |
6894 | } |
6895 | ||
6896 | void perf_event_exec(void) | |
6897 | { | |
6898 | struct perf_event_context *ctx; | |
6899 | int ctxn; | |
6900 | ||
6901 | rcu_read_lock(); | |
6902 | for_each_task_context_nr(ctxn) { | |
6903 | ctx = current->perf_event_ctxp[ctxn]; | |
6904 | if (!ctx) | |
6905 | continue; | |
6906 | ||
6907 | perf_event_enable_on_exec(ctxn); | |
6908 | ||
aab5b71e | 6909 | perf_iterate_ctx(ctx, perf_event_addr_filters_exec, NULL, |
375637bc AS |
6910 | true); |
6911 | } | |
6912 | rcu_read_unlock(); | |
6913 | } | |
6914 | ||
95ff4ca2 AS |
6915 | struct remote_output { |
6916 | struct ring_buffer *rb; | |
6917 | int err; | |
6918 | }; | |
6919 | ||
6920 | static void __perf_event_output_stop(struct perf_event *event, void *data) | |
6921 | { | |
6922 | struct perf_event *parent = event->parent; | |
6923 | struct remote_output *ro = data; | |
6924 | struct ring_buffer *rb = ro->rb; | |
375637bc AS |
6925 | struct stop_event_data sd = { |
6926 | .event = event, | |
6927 | }; | |
95ff4ca2 AS |
6928 | |
6929 | if (!has_aux(event)) | |
6930 | return; | |
6931 | ||
6932 | if (!parent) | |
6933 | parent = event; | |
6934 | ||
6935 | /* | |
6936 | * In case of inheritance, it will be the parent that links to the | |
767ae086 AS |
6937 | * ring-buffer, but it will be the child that's actually using it. |
6938 | * | |
6939 | * We are using event::rb to determine if the event should be stopped, | |
6940 | * however this may race with ring_buffer_attach() (through set_output), | |
6941 | * which will make us skip the event that actually needs to be stopped. | |
6942 | * So ring_buffer_attach() has to stop an aux event before re-assigning | |
6943 | * its rb pointer. | |
95ff4ca2 AS |
6944 | */ |
6945 | if (rcu_dereference(parent->rb) == rb) | |
375637bc | 6946 | ro->err = __perf_event_stop(&sd); |
95ff4ca2 AS |
6947 | } |
6948 | ||
6949 | static int __perf_pmu_output_stop(void *info) | |
6950 | { | |
6951 | struct perf_event *event = info; | |
f3a519e4 | 6952 | struct pmu *pmu = event->ctx->pmu; |
8b6a3fe8 | 6953 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
95ff4ca2 AS |
6954 | struct remote_output ro = { |
6955 | .rb = event->rb, | |
6956 | }; | |
6957 | ||
6958 | rcu_read_lock(); | |
aab5b71e | 6959 | perf_iterate_ctx(&cpuctx->ctx, __perf_event_output_stop, &ro, false); |
95ff4ca2 | 6960 | if (cpuctx->task_ctx) |
aab5b71e | 6961 | perf_iterate_ctx(cpuctx->task_ctx, __perf_event_output_stop, |
b73e4fef | 6962 | &ro, false); |
95ff4ca2 AS |
6963 | rcu_read_unlock(); |
6964 | ||
6965 | return ro.err; | |
6966 | } | |
6967 | ||
6968 | static void perf_pmu_output_stop(struct perf_event *event) | |
6969 | { | |
6970 | struct perf_event *iter; | |
6971 | int err, cpu; | |
6972 | ||
6973 | restart: | |
6974 | rcu_read_lock(); | |
6975 | list_for_each_entry_rcu(iter, &event->rb->event_list, rb_entry) { | |
6976 | /* | |
6977 | * For per-CPU events, we need to make sure that neither they | |
6978 | * nor their children are running; for cpu==-1 events it's | |
6979 | * sufficient to stop the event itself if it's active, since | |
6980 | * it can't have children. | |
6981 | */ | |
6982 | cpu = iter->cpu; | |
6983 | if (cpu == -1) | |
6984 | cpu = READ_ONCE(iter->oncpu); | |
6985 | ||
6986 | if (cpu == -1) | |
6987 | continue; | |
6988 | ||
6989 | err = cpu_function_call(cpu, __perf_pmu_output_stop, event); | |
6990 | if (err == -EAGAIN) { | |
6991 | rcu_read_unlock(); | |
6992 | goto restart; | |
6993 | } | |
6994 | } | |
6995 | rcu_read_unlock(); | |
52d857a8 JO |
6996 | } |
6997 | ||
60313ebe | 6998 | /* |
9f498cc5 PZ |
6999 | * task tracking -- fork/exit |
7000 | * | |
13d7a241 | 7001 | * enabled by: attr.comm | attr.mmap | attr.mmap2 | attr.mmap_data | attr.task |
60313ebe PZ |
7002 | */ |
7003 | ||
9f498cc5 | 7004 | struct perf_task_event { |
3a80b4a3 | 7005 | struct task_struct *task; |
cdd6c482 | 7006 | struct perf_event_context *task_ctx; |
60313ebe PZ |
7007 | |
7008 | struct { | |
7009 | struct perf_event_header header; | |
7010 | ||
7011 | u32 pid; | |
7012 | u32 ppid; | |
9f498cc5 PZ |
7013 | u32 tid; |
7014 | u32 ptid; | |
393b2ad8 | 7015 | u64 time; |
cdd6c482 | 7016 | } event_id; |
60313ebe PZ |
7017 | }; |
7018 | ||
67516844 JO |
7019 | static int perf_event_task_match(struct perf_event *event) |
7020 | { | |
13d7a241 SE |
7021 | return event->attr.comm || event->attr.mmap || |
7022 | event->attr.mmap2 || event->attr.mmap_data || | |
7023 | event->attr.task; | |
67516844 JO |
7024 | } |
7025 | ||
cdd6c482 | 7026 | static void perf_event_task_output(struct perf_event *event, |
52d857a8 | 7027 | void *data) |
60313ebe | 7028 | { |
52d857a8 | 7029 | struct perf_task_event *task_event = data; |
60313ebe | 7030 | struct perf_output_handle handle; |
c980d109 | 7031 | struct perf_sample_data sample; |
9f498cc5 | 7032 | struct task_struct *task = task_event->task; |
c980d109 | 7033 | int ret, size = task_event->event_id.header.size; |
8bb39f9a | 7034 | |
67516844 JO |
7035 | if (!perf_event_task_match(event)) |
7036 | return; | |
7037 | ||
c980d109 | 7038 | perf_event_header__init_id(&task_event->event_id.header, &sample, event); |
60313ebe | 7039 | |
c980d109 | 7040 | ret = perf_output_begin(&handle, event, |
a7ac67ea | 7041 | task_event->event_id.header.size); |
ef60777c | 7042 | if (ret) |
c980d109 | 7043 | goto out; |
60313ebe | 7044 | |
cdd6c482 IM |
7045 | task_event->event_id.pid = perf_event_pid(event, task); |
7046 | task_event->event_id.ppid = perf_event_pid(event, current); | |
60313ebe | 7047 | |
cdd6c482 IM |
7048 | task_event->event_id.tid = perf_event_tid(event, task); |
7049 | task_event->event_id.ptid = perf_event_tid(event, current); | |
9f498cc5 | 7050 | |
34f43927 PZ |
7051 | task_event->event_id.time = perf_event_clock(event); |
7052 | ||
cdd6c482 | 7053 | perf_output_put(&handle, task_event->event_id); |
393b2ad8 | 7054 | |
c980d109 ACM |
7055 | perf_event__output_id_sample(event, &handle, &sample); |
7056 | ||
60313ebe | 7057 | perf_output_end(&handle); |
c980d109 ACM |
7058 | out: |
7059 | task_event->event_id.header.size = size; | |
60313ebe PZ |
7060 | } |
7061 | ||
cdd6c482 IM |
7062 | static void perf_event_task(struct task_struct *task, |
7063 | struct perf_event_context *task_ctx, | |
3a80b4a3 | 7064 | int new) |
60313ebe | 7065 | { |
9f498cc5 | 7066 | struct perf_task_event task_event; |
60313ebe | 7067 | |
cdd6c482 IM |
7068 | if (!atomic_read(&nr_comm_events) && |
7069 | !atomic_read(&nr_mmap_events) && | |
7070 | !atomic_read(&nr_task_events)) | |
60313ebe PZ |
7071 | return; |
7072 | ||
9f498cc5 | 7073 | task_event = (struct perf_task_event){ |
3a80b4a3 PZ |
7074 | .task = task, |
7075 | .task_ctx = task_ctx, | |
cdd6c482 | 7076 | .event_id = { |
60313ebe | 7077 | .header = { |
cdd6c482 | 7078 | .type = new ? PERF_RECORD_FORK : PERF_RECORD_EXIT, |
573402db | 7079 | .misc = 0, |
cdd6c482 | 7080 | .size = sizeof(task_event.event_id), |
60313ebe | 7081 | }, |
573402db PZ |
7082 | /* .pid */ |
7083 | /* .ppid */ | |
9f498cc5 PZ |
7084 | /* .tid */ |
7085 | /* .ptid */ | |
34f43927 | 7086 | /* .time */ |
60313ebe PZ |
7087 | }, |
7088 | }; | |
7089 | ||
aab5b71e | 7090 | perf_iterate_sb(perf_event_task_output, |
52d857a8 JO |
7091 | &task_event, |
7092 | task_ctx); | |
9f498cc5 PZ |
7093 | } |
7094 | ||
cdd6c482 | 7095 | void perf_event_fork(struct task_struct *task) |
9f498cc5 | 7096 | { |
cdd6c482 | 7097 | perf_event_task(task, NULL, 1); |
e4222673 | 7098 | perf_event_namespaces(task); |
60313ebe PZ |
7099 | } |
7100 | ||
8d1b2d93 PZ |
7101 | /* |
7102 | * comm tracking | |
7103 | */ | |
7104 | ||
7105 | struct perf_comm_event { | |
22a4f650 IM |
7106 | struct task_struct *task; |
7107 | char *comm; | |
8d1b2d93 PZ |
7108 | int comm_size; |
7109 | ||
7110 | struct { | |
7111 | struct perf_event_header header; | |
7112 | ||
7113 | u32 pid; | |
7114 | u32 tid; | |
cdd6c482 | 7115 | } event_id; |
8d1b2d93 PZ |
7116 | }; |
7117 | ||
67516844 JO |
7118 | static int perf_event_comm_match(struct perf_event *event) |
7119 | { | |
7120 | return event->attr.comm; | |
7121 | } | |
7122 | ||
cdd6c482 | 7123 | static void perf_event_comm_output(struct perf_event *event, |
52d857a8 | 7124 | void *data) |
8d1b2d93 | 7125 | { |
52d857a8 | 7126 | struct perf_comm_event *comm_event = data; |
8d1b2d93 | 7127 | struct perf_output_handle handle; |
c980d109 | 7128 | struct perf_sample_data sample; |
cdd6c482 | 7129 | int size = comm_event->event_id.header.size; |
c980d109 ACM |
7130 | int ret; |
7131 | ||
67516844 JO |
7132 | if (!perf_event_comm_match(event)) |
7133 | return; | |
7134 | ||
c980d109 ACM |
7135 | perf_event_header__init_id(&comm_event->event_id.header, &sample, event); |
7136 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 7137 | comm_event->event_id.header.size); |
8d1b2d93 PZ |
7138 | |
7139 | if (ret) | |
c980d109 | 7140 | goto out; |
8d1b2d93 | 7141 | |
cdd6c482 IM |
7142 | comm_event->event_id.pid = perf_event_pid(event, comm_event->task); |
7143 | comm_event->event_id.tid = perf_event_tid(event, comm_event->task); | |
709e50cf | 7144 | |
cdd6c482 | 7145 | perf_output_put(&handle, comm_event->event_id); |
76369139 | 7146 | __output_copy(&handle, comm_event->comm, |
8d1b2d93 | 7147 | comm_event->comm_size); |
c980d109 ACM |
7148 | |
7149 | perf_event__output_id_sample(event, &handle, &sample); | |
7150 | ||
8d1b2d93 | 7151 | perf_output_end(&handle); |
c980d109 ACM |
7152 | out: |
7153 | comm_event->event_id.header.size = size; | |
8d1b2d93 PZ |
7154 | } |
7155 | ||
cdd6c482 | 7156 | static void perf_event_comm_event(struct perf_comm_event *comm_event) |
8d1b2d93 | 7157 | { |
413ee3b4 | 7158 | char comm[TASK_COMM_LEN]; |
8d1b2d93 | 7159 | unsigned int size; |
8d1b2d93 | 7160 | |
413ee3b4 | 7161 | memset(comm, 0, sizeof(comm)); |
96b02d78 | 7162 | strlcpy(comm, comm_event->task->comm, sizeof(comm)); |
888fcee0 | 7163 | size = ALIGN(strlen(comm)+1, sizeof(u64)); |
8d1b2d93 PZ |
7164 | |
7165 | comm_event->comm = comm; | |
7166 | comm_event->comm_size = size; | |
7167 | ||
cdd6c482 | 7168 | comm_event->event_id.header.size = sizeof(comm_event->event_id) + size; |
8dc85d54 | 7169 | |
aab5b71e | 7170 | perf_iterate_sb(perf_event_comm_output, |
52d857a8 JO |
7171 | comm_event, |
7172 | NULL); | |
8d1b2d93 PZ |
7173 | } |
7174 | ||
82b89778 | 7175 | void perf_event_comm(struct task_struct *task, bool exec) |
8d1b2d93 | 7176 | { |
9ee318a7 PZ |
7177 | struct perf_comm_event comm_event; |
7178 | ||
cdd6c482 | 7179 | if (!atomic_read(&nr_comm_events)) |
9ee318a7 | 7180 | return; |
a63eaf34 | 7181 | |
9ee318a7 | 7182 | comm_event = (struct perf_comm_event){ |
8d1b2d93 | 7183 | .task = task, |
573402db PZ |
7184 | /* .comm */ |
7185 | /* .comm_size */ | |
cdd6c482 | 7186 | .event_id = { |
573402db | 7187 | .header = { |
cdd6c482 | 7188 | .type = PERF_RECORD_COMM, |
82b89778 | 7189 | .misc = exec ? PERF_RECORD_MISC_COMM_EXEC : 0, |
573402db PZ |
7190 | /* .size */ |
7191 | }, | |
7192 | /* .pid */ | |
7193 | /* .tid */ | |
8d1b2d93 PZ |
7194 | }, |
7195 | }; | |
7196 | ||
cdd6c482 | 7197 | perf_event_comm_event(&comm_event); |
8d1b2d93 PZ |
7198 | } |
7199 | ||
e4222673 HB |
7200 | /* |
7201 | * namespaces tracking | |
7202 | */ | |
7203 | ||
7204 | struct perf_namespaces_event { | |
7205 | struct task_struct *task; | |
7206 | ||
7207 | struct { | |
7208 | struct perf_event_header header; | |
7209 | ||
7210 | u32 pid; | |
7211 | u32 tid; | |
7212 | u64 nr_namespaces; | |
7213 | struct perf_ns_link_info link_info[NR_NAMESPACES]; | |
7214 | } event_id; | |
7215 | }; | |
7216 | ||
7217 | static int perf_event_namespaces_match(struct perf_event *event) | |
7218 | { | |
7219 | return event->attr.namespaces; | |
7220 | } | |
7221 | ||
7222 | static void perf_event_namespaces_output(struct perf_event *event, | |
7223 | void *data) | |
7224 | { | |
7225 | struct perf_namespaces_event *namespaces_event = data; | |
7226 | struct perf_output_handle handle; | |
7227 | struct perf_sample_data sample; | |
34900ec5 | 7228 | u16 header_size = namespaces_event->event_id.header.size; |
e4222673 HB |
7229 | int ret; |
7230 | ||
7231 | if (!perf_event_namespaces_match(event)) | |
7232 | return; | |
7233 | ||
7234 | perf_event_header__init_id(&namespaces_event->event_id.header, | |
7235 | &sample, event); | |
7236 | ret = perf_output_begin(&handle, event, | |
7237 | namespaces_event->event_id.header.size); | |
7238 | if (ret) | |
34900ec5 | 7239 | goto out; |
e4222673 HB |
7240 | |
7241 | namespaces_event->event_id.pid = perf_event_pid(event, | |
7242 | namespaces_event->task); | |
7243 | namespaces_event->event_id.tid = perf_event_tid(event, | |
7244 | namespaces_event->task); | |
7245 | ||
7246 | perf_output_put(&handle, namespaces_event->event_id); | |
7247 | ||
7248 | perf_event__output_id_sample(event, &handle, &sample); | |
7249 | ||
7250 | perf_output_end(&handle); | |
34900ec5 JO |
7251 | out: |
7252 | namespaces_event->event_id.header.size = header_size; | |
e4222673 HB |
7253 | } |
7254 | ||
7255 | static void perf_fill_ns_link_info(struct perf_ns_link_info *ns_link_info, | |
7256 | struct task_struct *task, | |
7257 | const struct proc_ns_operations *ns_ops) | |
7258 | { | |
7259 | struct path ns_path; | |
7260 | struct inode *ns_inode; | |
7261 | void *error; | |
7262 | ||
7263 | error = ns_get_path(&ns_path, task, ns_ops); | |
7264 | if (!error) { | |
7265 | ns_inode = ns_path.dentry->d_inode; | |
7266 | ns_link_info->dev = new_encode_dev(ns_inode->i_sb->s_dev); | |
7267 | ns_link_info->ino = ns_inode->i_ino; | |
0e18dd12 | 7268 | path_put(&ns_path); |
e4222673 HB |
7269 | } |
7270 | } | |
7271 | ||
7272 | void perf_event_namespaces(struct task_struct *task) | |
7273 | { | |
7274 | struct perf_namespaces_event namespaces_event; | |
7275 | struct perf_ns_link_info *ns_link_info; | |
7276 | ||
7277 | if (!atomic_read(&nr_namespaces_events)) | |
7278 | return; | |
7279 | ||
7280 | namespaces_event = (struct perf_namespaces_event){ | |
7281 | .task = task, | |
7282 | .event_id = { | |
7283 | .header = { | |
7284 | .type = PERF_RECORD_NAMESPACES, | |
7285 | .misc = 0, | |
7286 | .size = sizeof(namespaces_event.event_id), | |
7287 | }, | |
7288 | /* .pid */ | |
7289 | /* .tid */ | |
7290 | .nr_namespaces = NR_NAMESPACES, | |
7291 | /* .link_info[NR_NAMESPACES] */ | |
7292 | }, | |
7293 | }; | |
7294 | ||
7295 | ns_link_info = namespaces_event.event_id.link_info; | |
7296 | ||
7297 | perf_fill_ns_link_info(&ns_link_info[MNT_NS_INDEX], | |
7298 | task, &mntns_operations); | |
7299 | ||
7300 | #ifdef CONFIG_USER_NS | |
7301 | perf_fill_ns_link_info(&ns_link_info[USER_NS_INDEX], | |
7302 | task, &userns_operations); | |
7303 | #endif | |
7304 | #ifdef CONFIG_NET_NS | |
7305 | perf_fill_ns_link_info(&ns_link_info[NET_NS_INDEX], | |
7306 | task, &netns_operations); | |
7307 | #endif | |
7308 | #ifdef CONFIG_UTS_NS | |
7309 | perf_fill_ns_link_info(&ns_link_info[UTS_NS_INDEX], | |
7310 | task, &utsns_operations); | |
7311 | #endif | |
7312 | #ifdef CONFIG_IPC_NS | |
7313 | perf_fill_ns_link_info(&ns_link_info[IPC_NS_INDEX], | |
7314 | task, &ipcns_operations); | |
7315 | #endif | |
7316 | #ifdef CONFIG_PID_NS | |
7317 | perf_fill_ns_link_info(&ns_link_info[PID_NS_INDEX], | |
7318 | task, &pidns_operations); | |
7319 | #endif | |
7320 | #ifdef CONFIG_CGROUPS | |
7321 | perf_fill_ns_link_info(&ns_link_info[CGROUP_NS_INDEX], | |
7322 | task, &cgroupns_operations); | |
7323 | #endif | |
7324 | ||
7325 | perf_iterate_sb(perf_event_namespaces_output, | |
7326 | &namespaces_event, | |
7327 | NULL); | |
7328 | } | |
7329 | ||
0a4a9391 PZ |
7330 | /* |
7331 | * mmap tracking | |
7332 | */ | |
7333 | ||
7334 | struct perf_mmap_event { | |
089dd79d PZ |
7335 | struct vm_area_struct *vma; |
7336 | ||
7337 | const char *file_name; | |
7338 | int file_size; | |
13d7a241 SE |
7339 | int maj, min; |
7340 | u64 ino; | |
7341 | u64 ino_generation; | |
f972eb63 | 7342 | u32 prot, flags; |
0a4a9391 PZ |
7343 | |
7344 | struct { | |
7345 | struct perf_event_header header; | |
7346 | ||
7347 | u32 pid; | |
7348 | u32 tid; | |
7349 | u64 start; | |
7350 | u64 len; | |
7351 | u64 pgoff; | |
cdd6c482 | 7352 | } event_id; |
0a4a9391 PZ |
7353 | }; |
7354 | ||
67516844 JO |
7355 | static int perf_event_mmap_match(struct perf_event *event, |
7356 | void *data) | |
7357 | { | |
7358 | struct perf_mmap_event *mmap_event = data; | |
7359 | struct vm_area_struct *vma = mmap_event->vma; | |
7360 | int executable = vma->vm_flags & VM_EXEC; | |
7361 | ||
7362 | return (!executable && event->attr.mmap_data) || | |
13d7a241 | 7363 | (executable && (event->attr.mmap || event->attr.mmap2)); |
67516844 JO |
7364 | } |
7365 | ||
cdd6c482 | 7366 | static void perf_event_mmap_output(struct perf_event *event, |
52d857a8 | 7367 | void *data) |
0a4a9391 | 7368 | { |
52d857a8 | 7369 | struct perf_mmap_event *mmap_event = data; |
0a4a9391 | 7370 | struct perf_output_handle handle; |
c980d109 | 7371 | struct perf_sample_data sample; |
cdd6c482 | 7372 | int size = mmap_event->event_id.header.size; |
d9c1bb2f | 7373 | u32 type = mmap_event->event_id.header.type; |
c980d109 | 7374 | int ret; |
0a4a9391 | 7375 | |
67516844 JO |
7376 | if (!perf_event_mmap_match(event, data)) |
7377 | return; | |
7378 | ||
13d7a241 SE |
7379 | if (event->attr.mmap2) { |
7380 | mmap_event->event_id.header.type = PERF_RECORD_MMAP2; | |
7381 | mmap_event->event_id.header.size += sizeof(mmap_event->maj); | |
7382 | mmap_event->event_id.header.size += sizeof(mmap_event->min); | |
7383 | mmap_event->event_id.header.size += sizeof(mmap_event->ino); | |
d008d525 | 7384 | mmap_event->event_id.header.size += sizeof(mmap_event->ino_generation); |
f972eb63 PZ |
7385 | mmap_event->event_id.header.size += sizeof(mmap_event->prot); |
7386 | mmap_event->event_id.header.size += sizeof(mmap_event->flags); | |
13d7a241 SE |
7387 | } |
7388 | ||
c980d109 ACM |
7389 | perf_event_header__init_id(&mmap_event->event_id.header, &sample, event); |
7390 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 7391 | mmap_event->event_id.header.size); |
0a4a9391 | 7392 | if (ret) |
c980d109 | 7393 | goto out; |
0a4a9391 | 7394 | |
cdd6c482 IM |
7395 | mmap_event->event_id.pid = perf_event_pid(event, current); |
7396 | mmap_event->event_id.tid = perf_event_tid(event, current); | |
709e50cf | 7397 | |
cdd6c482 | 7398 | perf_output_put(&handle, mmap_event->event_id); |
13d7a241 SE |
7399 | |
7400 | if (event->attr.mmap2) { | |
7401 | perf_output_put(&handle, mmap_event->maj); | |
7402 | perf_output_put(&handle, mmap_event->min); | |
7403 | perf_output_put(&handle, mmap_event->ino); | |
7404 | perf_output_put(&handle, mmap_event->ino_generation); | |
f972eb63 PZ |
7405 | perf_output_put(&handle, mmap_event->prot); |
7406 | perf_output_put(&handle, mmap_event->flags); | |
13d7a241 SE |
7407 | } |
7408 | ||
76369139 | 7409 | __output_copy(&handle, mmap_event->file_name, |
0a4a9391 | 7410 | mmap_event->file_size); |
c980d109 ACM |
7411 | |
7412 | perf_event__output_id_sample(event, &handle, &sample); | |
7413 | ||
78d613eb | 7414 | perf_output_end(&handle); |
c980d109 ACM |
7415 | out: |
7416 | mmap_event->event_id.header.size = size; | |
d9c1bb2f | 7417 | mmap_event->event_id.header.type = type; |
0a4a9391 PZ |
7418 | } |
7419 | ||
cdd6c482 | 7420 | static void perf_event_mmap_event(struct perf_mmap_event *mmap_event) |
0a4a9391 | 7421 | { |
089dd79d PZ |
7422 | struct vm_area_struct *vma = mmap_event->vma; |
7423 | struct file *file = vma->vm_file; | |
13d7a241 SE |
7424 | int maj = 0, min = 0; |
7425 | u64 ino = 0, gen = 0; | |
f972eb63 | 7426 | u32 prot = 0, flags = 0; |
0a4a9391 PZ |
7427 | unsigned int size; |
7428 | char tmp[16]; | |
7429 | char *buf = NULL; | |
2c42cfbf | 7430 | char *name; |
413ee3b4 | 7431 | |
0b3589be PZ |
7432 | if (vma->vm_flags & VM_READ) |
7433 | prot |= PROT_READ; | |
7434 | if (vma->vm_flags & VM_WRITE) | |
7435 | prot |= PROT_WRITE; | |
7436 | if (vma->vm_flags & VM_EXEC) | |
7437 | prot |= PROT_EXEC; | |
7438 | ||
7439 | if (vma->vm_flags & VM_MAYSHARE) | |
7440 | flags = MAP_SHARED; | |
7441 | else | |
7442 | flags = MAP_PRIVATE; | |
7443 | ||
7444 | if (vma->vm_flags & VM_DENYWRITE) | |
7445 | flags |= MAP_DENYWRITE; | |
7446 | if (vma->vm_flags & VM_MAYEXEC) | |
7447 | flags |= MAP_EXECUTABLE; | |
7448 | if (vma->vm_flags & VM_LOCKED) | |
7449 | flags |= MAP_LOCKED; | |
7450 | if (vma->vm_flags & VM_HUGETLB) | |
7451 | flags |= MAP_HUGETLB; | |
7452 | ||
0a4a9391 | 7453 | if (file) { |
13d7a241 SE |
7454 | struct inode *inode; |
7455 | dev_t dev; | |
3ea2f2b9 | 7456 | |
2c42cfbf | 7457 | buf = kmalloc(PATH_MAX, GFP_KERNEL); |
0a4a9391 | 7458 | if (!buf) { |
c7e548b4 ON |
7459 | name = "//enomem"; |
7460 | goto cpy_name; | |
0a4a9391 | 7461 | } |
413ee3b4 | 7462 | /* |
3ea2f2b9 | 7463 | * d_path() works from the end of the rb backwards, so we |
413ee3b4 AB |
7464 | * need to add enough zero bytes after the string to handle |
7465 | * the 64bit alignment we do later. | |
7466 | */ | |
9bf39ab2 | 7467 | name = file_path(file, buf, PATH_MAX - sizeof(u64)); |
0a4a9391 | 7468 | if (IS_ERR(name)) { |
c7e548b4 ON |
7469 | name = "//toolong"; |
7470 | goto cpy_name; | |
0a4a9391 | 7471 | } |
13d7a241 SE |
7472 | inode = file_inode(vma->vm_file); |
7473 | dev = inode->i_sb->s_dev; | |
7474 | ino = inode->i_ino; | |
7475 | gen = inode->i_generation; | |
7476 | maj = MAJOR(dev); | |
7477 | min = MINOR(dev); | |
f972eb63 | 7478 | |
c7e548b4 | 7479 | goto got_name; |
0a4a9391 | 7480 | } else { |
fbe26abe JO |
7481 | if (vma->vm_ops && vma->vm_ops->name) { |
7482 | name = (char *) vma->vm_ops->name(vma); | |
7483 | if (name) | |
7484 | goto cpy_name; | |
7485 | } | |
7486 | ||
2c42cfbf | 7487 | name = (char *)arch_vma_name(vma); |
c7e548b4 ON |
7488 | if (name) |
7489 | goto cpy_name; | |
089dd79d | 7490 | |
32c5fb7e | 7491 | if (vma->vm_start <= vma->vm_mm->start_brk && |
3af9e859 | 7492 | vma->vm_end >= vma->vm_mm->brk) { |
c7e548b4 ON |
7493 | name = "[heap]"; |
7494 | goto cpy_name; | |
32c5fb7e ON |
7495 | } |
7496 | if (vma->vm_start <= vma->vm_mm->start_stack && | |
3af9e859 | 7497 | vma->vm_end >= vma->vm_mm->start_stack) { |
c7e548b4 ON |
7498 | name = "[stack]"; |
7499 | goto cpy_name; | |
089dd79d PZ |
7500 | } |
7501 | ||
c7e548b4 ON |
7502 | name = "//anon"; |
7503 | goto cpy_name; | |
0a4a9391 PZ |
7504 | } |
7505 | ||
c7e548b4 ON |
7506 | cpy_name: |
7507 | strlcpy(tmp, name, sizeof(tmp)); | |
7508 | name = tmp; | |
0a4a9391 | 7509 | got_name: |
2c42cfbf PZ |
7510 | /* |
7511 | * Since our buffer works in 8 byte units we need to align our string | |
7512 | * size to a multiple of 8. However, we must guarantee the tail end is | |
7513 | * zero'd out to avoid leaking random bits to userspace. | |
7514 | */ | |
7515 | size = strlen(name)+1; | |
7516 | while (!IS_ALIGNED(size, sizeof(u64))) | |
7517 | name[size++] = '\0'; | |
0a4a9391 PZ |
7518 | |
7519 | mmap_event->file_name = name; | |
7520 | mmap_event->file_size = size; | |
13d7a241 SE |
7521 | mmap_event->maj = maj; |
7522 | mmap_event->min = min; | |
7523 | mmap_event->ino = ino; | |
7524 | mmap_event->ino_generation = gen; | |
f972eb63 PZ |
7525 | mmap_event->prot = prot; |
7526 | mmap_event->flags = flags; | |
0a4a9391 | 7527 | |
2fe85427 SE |
7528 | if (!(vma->vm_flags & VM_EXEC)) |
7529 | mmap_event->event_id.header.misc |= PERF_RECORD_MISC_MMAP_DATA; | |
7530 | ||
cdd6c482 | 7531 | mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size; |
0a4a9391 | 7532 | |
aab5b71e | 7533 | perf_iterate_sb(perf_event_mmap_output, |
52d857a8 JO |
7534 | mmap_event, |
7535 | NULL); | |
665c2142 | 7536 | |
0a4a9391 PZ |
7537 | kfree(buf); |
7538 | } | |
7539 | ||
375637bc AS |
7540 | /* |
7541 | * Check whether inode and address range match filter criteria. | |
7542 | */ | |
7543 | static bool perf_addr_filter_match(struct perf_addr_filter *filter, | |
7544 | struct file *file, unsigned long offset, | |
7545 | unsigned long size) | |
7546 | { | |
7f635ff1 MP |
7547 | /* d_inode(NULL) won't be equal to any mapped user-space file */ |
7548 | if (!filter->path.dentry) | |
7549 | return false; | |
7550 | ||
9511bce9 | 7551 | if (d_inode(filter->path.dentry) != file_inode(file)) |
375637bc AS |
7552 | return false; |
7553 | ||
7554 | if (filter->offset > offset + size) | |
7555 | return false; | |
7556 | ||
7557 | if (filter->offset + filter->size < offset) | |
7558 | return false; | |
7559 | ||
7560 | return true; | |
7561 | } | |
7562 | ||
c60f83b8 AS |
7563 | static bool perf_addr_filter_vma_adjust(struct perf_addr_filter *filter, |
7564 | struct vm_area_struct *vma, | |
7565 | struct perf_addr_filter_range *fr) | |
7566 | { | |
7567 | unsigned long vma_size = vma->vm_end - vma->vm_start; | |
7568 | unsigned long off = vma->vm_pgoff << PAGE_SHIFT; | |
7569 | struct file *file = vma->vm_file; | |
7570 | ||
7571 | if (!perf_addr_filter_match(filter, file, off, vma_size)) | |
7572 | return false; | |
7573 | ||
7574 | if (filter->offset < off) { | |
7575 | fr->start = vma->vm_start; | |
7576 | fr->size = min(vma_size, filter->size - (off - filter->offset)); | |
7577 | } else { | |
7578 | fr->start = vma->vm_start + filter->offset - off; | |
7579 | fr->size = min(vma->vm_end - fr->start, filter->size); | |
7580 | } | |
7581 | ||
7582 | return true; | |
7583 | } | |
7584 | ||
375637bc AS |
7585 | static void __perf_addr_filters_adjust(struct perf_event *event, void *data) |
7586 | { | |
7587 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
7588 | struct vm_area_struct *vma = data; | |
375637bc AS |
7589 | struct perf_addr_filter *filter; |
7590 | unsigned int restart = 0, count = 0; | |
c60f83b8 | 7591 | unsigned long flags; |
375637bc AS |
7592 | |
7593 | if (!has_addr_filter(event)) | |
7594 | return; | |
7595 | ||
c60f83b8 | 7596 | if (!vma->vm_file) |
375637bc AS |
7597 | return; |
7598 | ||
7599 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
7600 | list_for_each_entry(filter, &ifh->list, entry) { | |
c60f83b8 AS |
7601 | if (perf_addr_filter_vma_adjust(filter, vma, |
7602 | &event->addr_filter_ranges[count])) | |
375637bc | 7603 | restart++; |
375637bc AS |
7604 | |
7605 | count++; | |
7606 | } | |
7607 | ||
7608 | if (restart) | |
7609 | event->addr_filters_gen++; | |
7610 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
7611 | ||
7612 | if (restart) | |
767ae086 | 7613 | perf_event_stop(event, 1); |
375637bc AS |
7614 | } |
7615 | ||
7616 | /* | |
7617 | * Adjust all task's events' filters to the new vma | |
7618 | */ | |
7619 | static void perf_addr_filters_adjust(struct vm_area_struct *vma) | |
7620 | { | |
7621 | struct perf_event_context *ctx; | |
7622 | int ctxn; | |
7623 | ||
12b40a23 MP |
7624 | /* |
7625 | * Data tracing isn't supported yet and as such there is no need | |
7626 | * to keep track of anything that isn't related to executable code: | |
7627 | */ | |
7628 | if (!(vma->vm_flags & VM_EXEC)) | |
7629 | return; | |
7630 | ||
375637bc AS |
7631 | rcu_read_lock(); |
7632 | for_each_task_context_nr(ctxn) { | |
7633 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); | |
7634 | if (!ctx) | |
7635 | continue; | |
7636 | ||
aab5b71e | 7637 | perf_iterate_ctx(ctx, __perf_addr_filters_adjust, vma, true); |
375637bc AS |
7638 | } |
7639 | rcu_read_unlock(); | |
7640 | } | |
7641 | ||
3af9e859 | 7642 | void perf_event_mmap(struct vm_area_struct *vma) |
0a4a9391 | 7643 | { |
9ee318a7 PZ |
7644 | struct perf_mmap_event mmap_event; |
7645 | ||
cdd6c482 | 7646 | if (!atomic_read(&nr_mmap_events)) |
9ee318a7 PZ |
7647 | return; |
7648 | ||
7649 | mmap_event = (struct perf_mmap_event){ | |
089dd79d | 7650 | .vma = vma, |
573402db PZ |
7651 | /* .file_name */ |
7652 | /* .file_size */ | |
cdd6c482 | 7653 | .event_id = { |
573402db | 7654 | .header = { |
cdd6c482 | 7655 | .type = PERF_RECORD_MMAP, |
39447b38 | 7656 | .misc = PERF_RECORD_MISC_USER, |
573402db PZ |
7657 | /* .size */ |
7658 | }, | |
7659 | /* .pid */ | |
7660 | /* .tid */ | |
089dd79d PZ |
7661 | .start = vma->vm_start, |
7662 | .len = vma->vm_end - vma->vm_start, | |
3a0304e9 | 7663 | .pgoff = (u64)vma->vm_pgoff << PAGE_SHIFT, |
0a4a9391 | 7664 | }, |
13d7a241 SE |
7665 | /* .maj (attr_mmap2 only) */ |
7666 | /* .min (attr_mmap2 only) */ | |
7667 | /* .ino (attr_mmap2 only) */ | |
7668 | /* .ino_generation (attr_mmap2 only) */ | |
f972eb63 PZ |
7669 | /* .prot (attr_mmap2 only) */ |
7670 | /* .flags (attr_mmap2 only) */ | |
0a4a9391 PZ |
7671 | }; |
7672 | ||
375637bc | 7673 | perf_addr_filters_adjust(vma); |
cdd6c482 | 7674 | perf_event_mmap_event(&mmap_event); |
0a4a9391 PZ |
7675 | } |
7676 | ||
68db7e98 AS |
7677 | void perf_event_aux_event(struct perf_event *event, unsigned long head, |
7678 | unsigned long size, u64 flags) | |
7679 | { | |
7680 | struct perf_output_handle handle; | |
7681 | struct perf_sample_data sample; | |
7682 | struct perf_aux_event { | |
7683 | struct perf_event_header header; | |
7684 | u64 offset; | |
7685 | u64 size; | |
7686 | u64 flags; | |
7687 | } rec = { | |
7688 | .header = { | |
7689 | .type = PERF_RECORD_AUX, | |
7690 | .misc = 0, | |
7691 | .size = sizeof(rec), | |
7692 | }, | |
7693 | .offset = head, | |
7694 | .size = size, | |
7695 | .flags = flags, | |
7696 | }; | |
7697 | int ret; | |
7698 | ||
7699 | perf_event_header__init_id(&rec.header, &sample, event); | |
7700 | ret = perf_output_begin(&handle, event, rec.header.size); | |
7701 | ||
7702 | if (ret) | |
7703 | return; | |
7704 | ||
7705 | perf_output_put(&handle, rec); | |
7706 | perf_event__output_id_sample(event, &handle, &sample); | |
7707 | ||
7708 | perf_output_end(&handle); | |
7709 | } | |
7710 | ||
f38b0dbb KL |
7711 | /* |
7712 | * Lost/dropped samples logging | |
7713 | */ | |
7714 | void perf_log_lost_samples(struct perf_event *event, u64 lost) | |
7715 | { | |
7716 | struct perf_output_handle handle; | |
7717 | struct perf_sample_data sample; | |
7718 | int ret; | |
7719 | ||
7720 | struct { | |
7721 | struct perf_event_header header; | |
7722 | u64 lost; | |
7723 | } lost_samples_event = { | |
7724 | .header = { | |
7725 | .type = PERF_RECORD_LOST_SAMPLES, | |
7726 | .misc = 0, | |
7727 | .size = sizeof(lost_samples_event), | |
7728 | }, | |
7729 | .lost = lost, | |
7730 | }; | |
7731 | ||
7732 | perf_event_header__init_id(&lost_samples_event.header, &sample, event); | |
7733 | ||
7734 | ret = perf_output_begin(&handle, event, | |
7735 | lost_samples_event.header.size); | |
7736 | if (ret) | |
7737 | return; | |
7738 | ||
7739 | perf_output_put(&handle, lost_samples_event); | |
7740 | perf_event__output_id_sample(event, &handle, &sample); | |
7741 | perf_output_end(&handle); | |
7742 | } | |
7743 | ||
45ac1403 AH |
7744 | /* |
7745 | * context_switch tracking | |
7746 | */ | |
7747 | ||
7748 | struct perf_switch_event { | |
7749 | struct task_struct *task; | |
7750 | struct task_struct *next_prev; | |
7751 | ||
7752 | struct { | |
7753 | struct perf_event_header header; | |
7754 | u32 next_prev_pid; | |
7755 | u32 next_prev_tid; | |
7756 | } event_id; | |
7757 | }; | |
7758 | ||
7759 | static int perf_event_switch_match(struct perf_event *event) | |
7760 | { | |
7761 | return event->attr.context_switch; | |
7762 | } | |
7763 | ||
7764 | static void perf_event_switch_output(struct perf_event *event, void *data) | |
7765 | { | |
7766 | struct perf_switch_event *se = data; | |
7767 | struct perf_output_handle handle; | |
7768 | struct perf_sample_data sample; | |
7769 | int ret; | |
7770 | ||
7771 | if (!perf_event_switch_match(event)) | |
7772 | return; | |
7773 | ||
7774 | /* Only CPU-wide events are allowed to see next/prev pid/tid */ | |
7775 | if (event->ctx->task) { | |
7776 | se->event_id.header.type = PERF_RECORD_SWITCH; | |
7777 | se->event_id.header.size = sizeof(se->event_id.header); | |
7778 | } else { | |
7779 | se->event_id.header.type = PERF_RECORD_SWITCH_CPU_WIDE; | |
7780 | se->event_id.header.size = sizeof(se->event_id); | |
7781 | se->event_id.next_prev_pid = | |
7782 | perf_event_pid(event, se->next_prev); | |
7783 | se->event_id.next_prev_tid = | |
7784 | perf_event_tid(event, se->next_prev); | |
7785 | } | |
7786 | ||
7787 | perf_event_header__init_id(&se->event_id.header, &sample, event); | |
7788 | ||
7789 | ret = perf_output_begin(&handle, event, se->event_id.header.size); | |
7790 | if (ret) | |
7791 | return; | |
7792 | ||
7793 | if (event->ctx->task) | |
7794 | perf_output_put(&handle, se->event_id.header); | |
7795 | else | |
7796 | perf_output_put(&handle, se->event_id); | |
7797 | ||
7798 | perf_event__output_id_sample(event, &handle, &sample); | |
7799 | ||
7800 | perf_output_end(&handle); | |
7801 | } | |
7802 | ||
7803 | static void perf_event_switch(struct task_struct *task, | |
7804 | struct task_struct *next_prev, bool sched_in) | |
7805 | { | |
7806 | struct perf_switch_event switch_event; | |
7807 | ||
7808 | /* N.B. caller checks nr_switch_events != 0 */ | |
7809 | ||
7810 | switch_event = (struct perf_switch_event){ | |
7811 | .task = task, | |
7812 | .next_prev = next_prev, | |
7813 | .event_id = { | |
7814 | .header = { | |
7815 | /* .type */ | |
7816 | .misc = sched_in ? 0 : PERF_RECORD_MISC_SWITCH_OUT, | |
7817 | /* .size */ | |
7818 | }, | |
7819 | /* .next_prev_pid */ | |
7820 | /* .next_prev_tid */ | |
7821 | }, | |
7822 | }; | |
7823 | ||
101592b4 AB |
7824 | if (!sched_in && task->state == TASK_RUNNING) |
7825 | switch_event.event_id.header.misc |= | |
7826 | PERF_RECORD_MISC_SWITCH_OUT_PREEMPT; | |
7827 | ||
aab5b71e | 7828 | perf_iterate_sb(perf_event_switch_output, |
45ac1403 AH |
7829 | &switch_event, |
7830 | NULL); | |
7831 | } | |
7832 | ||
a78ac325 PZ |
7833 | /* |
7834 | * IRQ throttle logging | |
7835 | */ | |
7836 | ||
cdd6c482 | 7837 | static void perf_log_throttle(struct perf_event *event, int enable) |
a78ac325 PZ |
7838 | { |
7839 | struct perf_output_handle handle; | |
c980d109 | 7840 | struct perf_sample_data sample; |
a78ac325 PZ |
7841 | int ret; |
7842 | ||
7843 | struct { | |
7844 | struct perf_event_header header; | |
7845 | u64 time; | |
cca3f454 | 7846 | u64 id; |
7f453c24 | 7847 | u64 stream_id; |
a78ac325 PZ |
7848 | } throttle_event = { |
7849 | .header = { | |
cdd6c482 | 7850 | .type = PERF_RECORD_THROTTLE, |
a78ac325 PZ |
7851 | .misc = 0, |
7852 | .size = sizeof(throttle_event), | |
7853 | }, | |
34f43927 | 7854 | .time = perf_event_clock(event), |
cdd6c482 IM |
7855 | .id = primary_event_id(event), |
7856 | .stream_id = event->id, | |
a78ac325 PZ |
7857 | }; |
7858 | ||
966ee4d6 | 7859 | if (enable) |
cdd6c482 | 7860 | throttle_event.header.type = PERF_RECORD_UNTHROTTLE; |
966ee4d6 | 7861 | |
c980d109 ACM |
7862 | perf_event_header__init_id(&throttle_event.header, &sample, event); |
7863 | ||
7864 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 7865 | throttle_event.header.size); |
a78ac325 PZ |
7866 | if (ret) |
7867 | return; | |
7868 | ||
7869 | perf_output_put(&handle, throttle_event); | |
c980d109 | 7870 | perf_event__output_id_sample(event, &handle, &sample); |
a78ac325 PZ |
7871 | perf_output_end(&handle); |
7872 | } | |
7873 | ||
76193a94 SL |
7874 | /* |
7875 | * ksymbol register/unregister tracking | |
7876 | */ | |
7877 | ||
7878 | struct perf_ksymbol_event { | |
7879 | const char *name; | |
7880 | int name_len; | |
7881 | struct { | |
7882 | struct perf_event_header header; | |
7883 | u64 addr; | |
7884 | u32 len; | |
7885 | u16 ksym_type; | |
7886 | u16 flags; | |
7887 | } event_id; | |
7888 | }; | |
7889 | ||
7890 | static int perf_event_ksymbol_match(struct perf_event *event) | |
7891 | { | |
7892 | return event->attr.ksymbol; | |
7893 | } | |
7894 | ||
7895 | static void perf_event_ksymbol_output(struct perf_event *event, void *data) | |
7896 | { | |
7897 | struct perf_ksymbol_event *ksymbol_event = data; | |
7898 | struct perf_output_handle handle; | |
7899 | struct perf_sample_data sample; | |
7900 | int ret; | |
7901 | ||
7902 | if (!perf_event_ksymbol_match(event)) | |
7903 | return; | |
7904 | ||
7905 | perf_event_header__init_id(&ksymbol_event->event_id.header, | |
7906 | &sample, event); | |
7907 | ret = perf_output_begin(&handle, event, | |
7908 | ksymbol_event->event_id.header.size); | |
7909 | if (ret) | |
7910 | return; | |
7911 | ||
7912 | perf_output_put(&handle, ksymbol_event->event_id); | |
7913 | __output_copy(&handle, ksymbol_event->name, ksymbol_event->name_len); | |
7914 | perf_event__output_id_sample(event, &handle, &sample); | |
7915 | ||
7916 | perf_output_end(&handle); | |
7917 | } | |
7918 | ||
7919 | void perf_event_ksymbol(u16 ksym_type, u64 addr, u32 len, bool unregister, | |
7920 | const char *sym) | |
7921 | { | |
7922 | struct perf_ksymbol_event ksymbol_event; | |
7923 | char name[KSYM_NAME_LEN]; | |
7924 | u16 flags = 0; | |
7925 | int name_len; | |
7926 | ||
7927 | if (!atomic_read(&nr_ksymbol_events)) | |
7928 | return; | |
7929 | ||
7930 | if (ksym_type >= PERF_RECORD_KSYMBOL_TYPE_MAX || | |
7931 | ksym_type == PERF_RECORD_KSYMBOL_TYPE_UNKNOWN) | |
7932 | goto err; | |
7933 | ||
7934 | strlcpy(name, sym, KSYM_NAME_LEN); | |
7935 | name_len = strlen(name) + 1; | |
7936 | while (!IS_ALIGNED(name_len, sizeof(u64))) | |
7937 | name[name_len++] = '\0'; | |
7938 | BUILD_BUG_ON(KSYM_NAME_LEN % sizeof(u64)); | |
7939 | ||
7940 | if (unregister) | |
7941 | flags |= PERF_RECORD_KSYMBOL_FLAGS_UNREGISTER; | |
7942 | ||
7943 | ksymbol_event = (struct perf_ksymbol_event){ | |
7944 | .name = name, | |
7945 | .name_len = name_len, | |
7946 | .event_id = { | |
7947 | .header = { | |
7948 | .type = PERF_RECORD_KSYMBOL, | |
7949 | .size = sizeof(ksymbol_event.event_id) + | |
7950 | name_len, | |
7951 | }, | |
7952 | .addr = addr, | |
7953 | .len = len, | |
7954 | .ksym_type = ksym_type, | |
7955 | .flags = flags, | |
7956 | }, | |
7957 | }; | |
7958 | ||
7959 | perf_iterate_sb(perf_event_ksymbol_output, &ksymbol_event, NULL); | |
7960 | return; | |
7961 | err: | |
7962 | WARN_ONCE(1, "%s: Invalid KSYMBOL type 0x%x\n", __func__, ksym_type); | |
7963 | } | |
7964 | ||
6ee52e2a SL |
7965 | /* |
7966 | * bpf program load/unload tracking | |
7967 | */ | |
7968 | ||
7969 | struct perf_bpf_event { | |
7970 | struct bpf_prog *prog; | |
7971 | struct { | |
7972 | struct perf_event_header header; | |
7973 | u16 type; | |
7974 | u16 flags; | |
7975 | u32 id; | |
7976 | u8 tag[BPF_TAG_SIZE]; | |
7977 | } event_id; | |
7978 | }; | |
7979 | ||
7980 | static int perf_event_bpf_match(struct perf_event *event) | |
7981 | { | |
7982 | return event->attr.bpf_event; | |
7983 | } | |
7984 | ||
7985 | static void perf_event_bpf_output(struct perf_event *event, void *data) | |
7986 | { | |
7987 | struct perf_bpf_event *bpf_event = data; | |
7988 | struct perf_output_handle handle; | |
7989 | struct perf_sample_data sample; | |
7990 | int ret; | |
7991 | ||
7992 | if (!perf_event_bpf_match(event)) | |
7993 | return; | |
7994 | ||
7995 | perf_event_header__init_id(&bpf_event->event_id.header, | |
7996 | &sample, event); | |
7997 | ret = perf_output_begin(&handle, event, | |
7998 | bpf_event->event_id.header.size); | |
7999 | if (ret) | |
8000 | return; | |
8001 | ||
8002 | perf_output_put(&handle, bpf_event->event_id); | |
8003 | perf_event__output_id_sample(event, &handle, &sample); | |
8004 | ||
8005 | perf_output_end(&handle); | |
8006 | } | |
8007 | ||
8008 | static void perf_event_bpf_emit_ksymbols(struct bpf_prog *prog, | |
8009 | enum perf_bpf_event_type type) | |
8010 | { | |
8011 | bool unregister = type == PERF_BPF_EVENT_PROG_UNLOAD; | |
8012 | char sym[KSYM_NAME_LEN]; | |
8013 | int i; | |
8014 | ||
8015 | if (prog->aux->func_cnt == 0) { | |
8016 | bpf_get_prog_name(prog, sym); | |
8017 | perf_event_ksymbol(PERF_RECORD_KSYMBOL_TYPE_BPF, | |
8018 | (u64)(unsigned long)prog->bpf_func, | |
8019 | prog->jited_len, unregister, sym); | |
8020 | } else { | |
8021 | for (i = 0; i < prog->aux->func_cnt; i++) { | |
8022 | struct bpf_prog *subprog = prog->aux->func[i]; | |
8023 | ||
8024 | bpf_get_prog_name(subprog, sym); | |
8025 | perf_event_ksymbol( | |
8026 | PERF_RECORD_KSYMBOL_TYPE_BPF, | |
8027 | (u64)(unsigned long)subprog->bpf_func, | |
8028 | subprog->jited_len, unregister, sym); | |
8029 | } | |
8030 | } | |
8031 | } | |
8032 | ||
8033 | void perf_event_bpf_event(struct bpf_prog *prog, | |
8034 | enum perf_bpf_event_type type, | |
8035 | u16 flags) | |
8036 | { | |
8037 | struct perf_bpf_event bpf_event; | |
8038 | ||
8039 | if (type <= PERF_BPF_EVENT_UNKNOWN || | |
8040 | type >= PERF_BPF_EVENT_MAX) | |
8041 | return; | |
8042 | ||
8043 | switch (type) { | |
8044 | case PERF_BPF_EVENT_PROG_LOAD: | |
8045 | case PERF_BPF_EVENT_PROG_UNLOAD: | |
8046 | if (atomic_read(&nr_ksymbol_events)) | |
8047 | perf_event_bpf_emit_ksymbols(prog, type); | |
8048 | break; | |
8049 | default: | |
8050 | break; | |
8051 | } | |
8052 | ||
8053 | if (!atomic_read(&nr_bpf_events)) | |
8054 | return; | |
8055 | ||
8056 | bpf_event = (struct perf_bpf_event){ | |
8057 | .prog = prog, | |
8058 | .event_id = { | |
8059 | .header = { | |
8060 | .type = PERF_RECORD_BPF_EVENT, | |
8061 | .size = sizeof(bpf_event.event_id), | |
8062 | }, | |
8063 | .type = type, | |
8064 | .flags = flags, | |
8065 | .id = prog->aux->id, | |
8066 | }, | |
8067 | }; | |
8068 | ||
8069 | BUILD_BUG_ON(BPF_TAG_SIZE % sizeof(u64)); | |
8070 | ||
8071 | memcpy(bpf_event.event_id.tag, prog->tag, BPF_TAG_SIZE); | |
8072 | perf_iterate_sb(perf_event_bpf_output, &bpf_event, NULL); | |
8073 | } | |
8074 | ||
8d4e6c4c AS |
8075 | void perf_event_itrace_started(struct perf_event *event) |
8076 | { | |
8077 | event->attach_state |= PERF_ATTACH_ITRACE; | |
8078 | } | |
8079 | ||
ec0d7729 AS |
8080 | static void perf_log_itrace_start(struct perf_event *event) |
8081 | { | |
8082 | struct perf_output_handle handle; | |
8083 | struct perf_sample_data sample; | |
8084 | struct perf_aux_event { | |
8085 | struct perf_event_header header; | |
8086 | u32 pid; | |
8087 | u32 tid; | |
8088 | } rec; | |
8089 | int ret; | |
8090 | ||
8091 | if (event->parent) | |
8092 | event = event->parent; | |
8093 | ||
8094 | if (!(event->pmu->capabilities & PERF_PMU_CAP_ITRACE) || | |
8d4e6c4c | 8095 | event->attach_state & PERF_ATTACH_ITRACE) |
ec0d7729 AS |
8096 | return; |
8097 | ||
ec0d7729 AS |
8098 | rec.header.type = PERF_RECORD_ITRACE_START; |
8099 | rec.header.misc = 0; | |
8100 | rec.header.size = sizeof(rec); | |
8101 | rec.pid = perf_event_pid(event, current); | |
8102 | rec.tid = perf_event_tid(event, current); | |
8103 | ||
8104 | perf_event_header__init_id(&rec.header, &sample, event); | |
8105 | ret = perf_output_begin(&handle, event, rec.header.size); | |
8106 | ||
8107 | if (ret) | |
8108 | return; | |
8109 | ||
8110 | perf_output_put(&handle, rec); | |
8111 | perf_event__output_id_sample(event, &handle, &sample); | |
8112 | ||
8113 | perf_output_end(&handle); | |
8114 | } | |
8115 | ||
475113d9 JO |
8116 | static int |
8117 | __perf_event_account_interrupt(struct perf_event *event, int throttle) | |
f6c7d5fe | 8118 | { |
cdd6c482 | 8119 | struct hw_perf_event *hwc = &event->hw; |
79f14641 | 8120 | int ret = 0; |
475113d9 | 8121 | u64 seq; |
96398826 | 8122 | |
e050e3f0 SE |
8123 | seq = __this_cpu_read(perf_throttled_seq); |
8124 | if (seq != hwc->interrupts_seq) { | |
8125 | hwc->interrupts_seq = seq; | |
8126 | hwc->interrupts = 1; | |
8127 | } else { | |
8128 | hwc->interrupts++; | |
8129 | if (unlikely(throttle | |
8130 | && hwc->interrupts >= max_samples_per_tick)) { | |
8131 | __this_cpu_inc(perf_throttled_count); | |
555e0c1e | 8132 | tick_dep_set_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
163ec435 PZ |
8133 | hwc->interrupts = MAX_INTERRUPTS; |
8134 | perf_log_throttle(event, 0); | |
a78ac325 PZ |
8135 | ret = 1; |
8136 | } | |
e050e3f0 | 8137 | } |
60db5e09 | 8138 | |
cdd6c482 | 8139 | if (event->attr.freq) { |
def0a9b2 | 8140 | u64 now = perf_clock(); |
abd50713 | 8141 | s64 delta = now - hwc->freq_time_stamp; |
bd2b5b12 | 8142 | |
abd50713 | 8143 | hwc->freq_time_stamp = now; |
bd2b5b12 | 8144 | |
abd50713 | 8145 | if (delta > 0 && delta < 2*TICK_NSEC) |
f39d47ff | 8146 | perf_adjust_period(event, delta, hwc->last_period, true); |
bd2b5b12 PZ |
8147 | } |
8148 | ||
475113d9 JO |
8149 | return ret; |
8150 | } | |
8151 | ||
8152 | int perf_event_account_interrupt(struct perf_event *event) | |
8153 | { | |
8154 | return __perf_event_account_interrupt(event, 1); | |
8155 | } | |
8156 | ||
8157 | /* | |
8158 | * Generic event overflow handling, sampling. | |
8159 | */ | |
8160 | ||
8161 | static int __perf_event_overflow(struct perf_event *event, | |
8162 | int throttle, struct perf_sample_data *data, | |
8163 | struct pt_regs *regs) | |
8164 | { | |
8165 | int events = atomic_read(&event->event_limit); | |
8166 | int ret = 0; | |
8167 | ||
8168 | /* | |
8169 | * Non-sampling counters might still use the PMI to fold short | |
8170 | * hardware counters, ignore those. | |
8171 | */ | |
8172 | if (unlikely(!is_sampling_event(event))) | |
8173 | return 0; | |
8174 | ||
8175 | ret = __perf_event_account_interrupt(event, throttle); | |
cc1582c2 | 8176 | |
2023b359 PZ |
8177 | /* |
8178 | * XXX event_limit might not quite work as expected on inherited | |
cdd6c482 | 8179 | * events |
2023b359 PZ |
8180 | */ |
8181 | ||
cdd6c482 IM |
8182 | event->pending_kill = POLL_IN; |
8183 | if (events && atomic_dec_and_test(&event->event_limit)) { | |
79f14641 | 8184 | ret = 1; |
cdd6c482 | 8185 | event->pending_kill = POLL_HUP; |
5aab90ce JO |
8186 | |
8187 | perf_event_disable_inatomic(event); | |
79f14641 PZ |
8188 | } |
8189 | ||
aa6a5f3c | 8190 | READ_ONCE(event->overflow_handler)(event, data, regs); |
453f19ee | 8191 | |
fed66e2c | 8192 | if (*perf_event_fasync(event) && event->pending_kill) { |
a8b0ca17 PZ |
8193 | event->pending_wakeup = 1; |
8194 | irq_work_queue(&event->pending); | |
f506b3dc PZ |
8195 | } |
8196 | ||
79f14641 | 8197 | return ret; |
f6c7d5fe PZ |
8198 | } |
8199 | ||
a8b0ca17 | 8200 | int perf_event_overflow(struct perf_event *event, |
5622f295 MM |
8201 | struct perf_sample_data *data, |
8202 | struct pt_regs *regs) | |
850bc73f | 8203 | { |
a8b0ca17 | 8204 | return __perf_event_overflow(event, 1, data, regs); |
850bc73f PZ |
8205 | } |
8206 | ||
15dbf27c | 8207 | /* |
cdd6c482 | 8208 | * Generic software event infrastructure |
15dbf27c PZ |
8209 | */ |
8210 | ||
b28ab83c PZ |
8211 | struct swevent_htable { |
8212 | struct swevent_hlist *swevent_hlist; | |
8213 | struct mutex hlist_mutex; | |
8214 | int hlist_refcount; | |
8215 | ||
8216 | /* Recursion avoidance in each contexts */ | |
8217 | int recursion[PERF_NR_CONTEXTS]; | |
8218 | }; | |
8219 | ||
8220 | static DEFINE_PER_CPU(struct swevent_htable, swevent_htable); | |
8221 | ||
7b4b6658 | 8222 | /* |
cdd6c482 IM |
8223 | * We directly increment event->count and keep a second value in |
8224 | * event->hw.period_left to count intervals. This period event | |
7b4b6658 PZ |
8225 | * is kept in the range [-sample_period, 0] so that we can use the |
8226 | * sign as trigger. | |
8227 | */ | |
8228 | ||
ab573844 | 8229 | u64 perf_swevent_set_period(struct perf_event *event) |
15dbf27c | 8230 | { |
cdd6c482 | 8231 | struct hw_perf_event *hwc = &event->hw; |
7b4b6658 PZ |
8232 | u64 period = hwc->last_period; |
8233 | u64 nr, offset; | |
8234 | s64 old, val; | |
8235 | ||
8236 | hwc->last_period = hwc->sample_period; | |
15dbf27c PZ |
8237 | |
8238 | again: | |
e7850595 | 8239 | old = val = local64_read(&hwc->period_left); |
7b4b6658 PZ |
8240 | if (val < 0) |
8241 | return 0; | |
15dbf27c | 8242 | |
7b4b6658 PZ |
8243 | nr = div64_u64(period + val, period); |
8244 | offset = nr * period; | |
8245 | val -= offset; | |
e7850595 | 8246 | if (local64_cmpxchg(&hwc->period_left, old, val) != old) |
7b4b6658 | 8247 | goto again; |
15dbf27c | 8248 | |
7b4b6658 | 8249 | return nr; |
15dbf27c PZ |
8250 | } |
8251 | ||
0cff784a | 8252 | static void perf_swevent_overflow(struct perf_event *event, u64 overflow, |
a8b0ca17 | 8253 | struct perf_sample_data *data, |
5622f295 | 8254 | struct pt_regs *regs) |
15dbf27c | 8255 | { |
cdd6c482 | 8256 | struct hw_perf_event *hwc = &event->hw; |
850bc73f | 8257 | int throttle = 0; |
15dbf27c | 8258 | |
0cff784a PZ |
8259 | if (!overflow) |
8260 | overflow = perf_swevent_set_period(event); | |
15dbf27c | 8261 | |
7b4b6658 PZ |
8262 | if (hwc->interrupts == MAX_INTERRUPTS) |
8263 | return; | |
15dbf27c | 8264 | |
7b4b6658 | 8265 | for (; overflow; overflow--) { |
a8b0ca17 | 8266 | if (__perf_event_overflow(event, throttle, |
5622f295 | 8267 | data, regs)) { |
7b4b6658 PZ |
8268 | /* |
8269 | * We inhibit the overflow from happening when | |
8270 | * hwc->interrupts == MAX_INTERRUPTS. | |
8271 | */ | |
8272 | break; | |
8273 | } | |
cf450a73 | 8274 | throttle = 1; |
7b4b6658 | 8275 | } |
15dbf27c PZ |
8276 | } |
8277 | ||
a4eaf7f1 | 8278 | static void perf_swevent_event(struct perf_event *event, u64 nr, |
a8b0ca17 | 8279 | struct perf_sample_data *data, |
5622f295 | 8280 | struct pt_regs *regs) |
7b4b6658 | 8281 | { |
cdd6c482 | 8282 | struct hw_perf_event *hwc = &event->hw; |
d6d020e9 | 8283 | |
e7850595 | 8284 | local64_add(nr, &event->count); |
d6d020e9 | 8285 | |
0cff784a PZ |
8286 | if (!regs) |
8287 | return; | |
8288 | ||
6c7e550f | 8289 | if (!is_sampling_event(event)) |
7b4b6658 | 8290 | return; |
d6d020e9 | 8291 | |
5d81e5cf AV |
8292 | if ((event->attr.sample_type & PERF_SAMPLE_PERIOD) && !event->attr.freq) { |
8293 | data->period = nr; | |
8294 | return perf_swevent_overflow(event, 1, data, regs); | |
8295 | } else | |
8296 | data->period = event->hw.last_period; | |
8297 | ||
0cff784a | 8298 | if (nr == 1 && hwc->sample_period == 1 && !event->attr.freq) |
a8b0ca17 | 8299 | return perf_swevent_overflow(event, 1, data, regs); |
0cff784a | 8300 | |
e7850595 | 8301 | if (local64_add_negative(nr, &hwc->period_left)) |
7b4b6658 | 8302 | return; |
df1a132b | 8303 | |
a8b0ca17 | 8304 | perf_swevent_overflow(event, 0, data, regs); |
d6d020e9 PZ |
8305 | } |
8306 | ||
f5ffe02e FW |
8307 | static int perf_exclude_event(struct perf_event *event, |
8308 | struct pt_regs *regs) | |
8309 | { | |
a4eaf7f1 | 8310 | if (event->hw.state & PERF_HES_STOPPED) |
91b2f482 | 8311 | return 1; |
a4eaf7f1 | 8312 | |
f5ffe02e FW |
8313 | if (regs) { |
8314 | if (event->attr.exclude_user && user_mode(regs)) | |
8315 | return 1; | |
8316 | ||
8317 | if (event->attr.exclude_kernel && !user_mode(regs)) | |
8318 | return 1; | |
8319 | } | |
8320 | ||
8321 | return 0; | |
8322 | } | |
8323 | ||
cdd6c482 | 8324 | static int perf_swevent_match(struct perf_event *event, |
1c432d89 | 8325 | enum perf_type_id type, |
6fb2915d LZ |
8326 | u32 event_id, |
8327 | struct perf_sample_data *data, | |
8328 | struct pt_regs *regs) | |
15dbf27c | 8329 | { |
cdd6c482 | 8330 | if (event->attr.type != type) |
a21ca2ca | 8331 | return 0; |
f5ffe02e | 8332 | |
cdd6c482 | 8333 | if (event->attr.config != event_id) |
15dbf27c PZ |
8334 | return 0; |
8335 | ||
f5ffe02e FW |
8336 | if (perf_exclude_event(event, regs)) |
8337 | return 0; | |
15dbf27c PZ |
8338 | |
8339 | return 1; | |
8340 | } | |
8341 | ||
76e1d904 FW |
8342 | static inline u64 swevent_hash(u64 type, u32 event_id) |
8343 | { | |
8344 | u64 val = event_id | (type << 32); | |
8345 | ||
8346 | return hash_64(val, SWEVENT_HLIST_BITS); | |
8347 | } | |
8348 | ||
49f135ed FW |
8349 | static inline struct hlist_head * |
8350 | __find_swevent_head(struct swevent_hlist *hlist, u64 type, u32 event_id) | |
76e1d904 | 8351 | { |
49f135ed FW |
8352 | u64 hash = swevent_hash(type, event_id); |
8353 | ||
8354 | return &hlist->heads[hash]; | |
8355 | } | |
76e1d904 | 8356 | |
49f135ed FW |
8357 | /* For the read side: events when they trigger */ |
8358 | static inline struct hlist_head * | |
b28ab83c | 8359 | find_swevent_head_rcu(struct swevent_htable *swhash, u64 type, u32 event_id) |
49f135ed FW |
8360 | { |
8361 | struct swevent_hlist *hlist; | |
76e1d904 | 8362 | |
b28ab83c | 8363 | hlist = rcu_dereference(swhash->swevent_hlist); |
76e1d904 FW |
8364 | if (!hlist) |
8365 | return NULL; | |
8366 | ||
49f135ed FW |
8367 | return __find_swevent_head(hlist, type, event_id); |
8368 | } | |
8369 | ||
8370 | /* For the event head insertion and removal in the hlist */ | |
8371 | static inline struct hlist_head * | |
b28ab83c | 8372 | find_swevent_head(struct swevent_htable *swhash, struct perf_event *event) |
49f135ed FW |
8373 | { |
8374 | struct swevent_hlist *hlist; | |
8375 | u32 event_id = event->attr.config; | |
8376 | u64 type = event->attr.type; | |
8377 | ||
8378 | /* | |
8379 | * Event scheduling is always serialized against hlist allocation | |
8380 | * and release. Which makes the protected version suitable here. | |
8381 | * The context lock guarantees that. | |
8382 | */ | |
b28ab83c | 8383 | hlist = rcu_dereference_protected(swhash->swevent_hlist, |
49f135ed FW |
8384 | lockdep_is_held(&event->ctx->lock)); |
8385 | if (!hlist) | |
8386 | return NULL; | |
8387 | ||
8388 | return __find_swevent_head(hlist, type, event_id); | |
76e1d904 FW |
8389 | } |
8390 | ||
8391 | static void do_perf_sw_event(enum perf_type_id type, u32 event_id, | |
a8b0ca17 | 8392 | u64 nr, |
76e1d904 FW |
8393 | struct perf_sample_data *data, |
8394 | struct pt_regs *regs) | |
15dbf27c | 8395 | { |
4a32fea9 | 8396 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 8397 | struct perf_event *event; |
76e1d904 | 8398 | struct hlist_head *head; |
15dbf27c | 8399 | |
76e1d904 | 8400 | rcu_read_lock(); |
b28ab83c | 8401 | head = find_swevent_head_rcu(swhash, type, event_id); |
76e1d904 FW |
8402 | if (!head) |
8403 | goto end; | |
8404 | ||
b67bfe0d | 8405 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
6fb2915d | 8406 | if (perf_swevent_match(event, type, event_id, data, regs)) |
a8b0ca17 | 8407 | perf_swevent_event(event, nr, data, regs); |
15dbf27c | 8408 | } |
76e1d904 FW |
8409 | end: |
8410 | rcu_read_unlock(); | |
15dbf27c PZ |
8411 | } |
8412 | ||
86038c5e PZI |
8413 | DEFINE_PER_CPU(struct pt_regs, __perf_regs[4]); |
8414 | ||
4ed7c92d | 8415 | int perf_swevent_get_recursion_context(void) |
96f6d444 | 8416 | { |
4a32fea9 | 8417 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
96f6d444 | 8418 | |
b28ab83c | 8419 | return get_recursion_context(swhash->recursion); |
96f6d444 | 8420 | } |
645e8cc0 | 8421 | EXPORT_SYMBOL_GPL(perf_swevent_get_recursion_context); |
96f6d444 | 8422 | |
98b5c2c6 | 8423 | void perf_swevent_put_recursion_context(int rctx) |
15dbf27c | 8424 | { |
4a32fea9 | 8425 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
927c7a9e | 8426 | |
b28ab83c | 8427 | put_recursion_context(swhash->recursion, rctx); |
ce71b9df | 8428 | } |
15dbf27c | 8429 | |
86038c5e | 8430 | void ___perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) |
b8e83514 | 8431 | { |
a4234bfc | 8432 | struct perf_sample_data data; |
4ed7c92d | 8433 | |
86038c5e | 8434 | if (WARN_ON_ONCE(!regs)) |
4ed7c92d | 8435 | return; |
a4234bfc | 8436 | |
fd0d000b | 8437 | perf_sample_data_init(&data, addr, 0); |
a8b0ca17 | 8438 | do_perf_sw_event(PERF_TYPE_SOFTWARE, event_id, nr, &data, regs); |
86038c5e PZI |
8439 | } |
8440 | ||
8441 | void __perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) | |
8442 | { | |
8443 | int rctx; | |
8444 | ||
8445 | preempt_disable_notrace(); | |
8446 | rctx = perf_swevent_get_recursion_context(); | |
8447 | if (unlikely(rctx < 0)) | |
8448 | goto fail; | |
8449 | ||
8450 | ___perf_sw_event(event_id, nr, regs, addr); | |
4ed7c92d PZ |
8451 | |
8452 | perf_swevent_put_recursion_context(rctx); | |
86038c5e | 8453 | fail: |
1c024eca | 8454 | preempt_enable_notrace(); |
b8e83514 PZ |
8455 | } |
8456 | ||
cdd6c482 | 8457 | static void perf_swevent_read(struct perf_event *event) |
15dbf27c | 8458 | { |
15dbf27c PZ |
8459 | } |
8460 | ||
a4eaf7f1 | 8461 | static int perf_swevent_add(struct perf_event *event, int flags) |
15dbf27c | 8462 | { |
4a32fea9 | 8463 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 8464 | struct hw_perf_event *hwc = &event->hw; |
76e1d904 FW |
8465 | struct hlist_head *head; |
8466 | ||
6c7e550f | 8467 | if (is_sampling_event(event)) { |
7b4b6658 | 8468 | hwc->last_period = hwc->sample_period; |
cdd6c482 | 8469 | perf_swevent_set_period(event); |
7b4b6658 | 8470 | } |
76e1d904 | 8471 | |
a4eaf7f1 PZ |
8472 | hwc->state = !(flags & PERF_EF_START); |
8473 | ||
b28ab83c | 8474 | head = find_swevent_head(swhash, event); |
12ca6ad2 | 8475 | if (WARN_ON_ONCE(!head)) |
76e1d904 FW |
8476 | return -EINVAL; |
8477 | ||
8478 | hlist_add_head_rcu(&event->hlist_entry, head); | |
6a694a60 | 8479 | perf_event_update_userpage(event); |
76e1d904 | 8480 | |
15dbf27c PZ |
8481 | return 0; |
8482 | } | |
8483 | ||
a4eaf7f1 | 8484 | static void perf_swevent_del(struct perf_event *event, int flags) |
15dbf27c | 8485 | { |
76e1d904 | 8486 | hlist_del_rcu(&event->hlist_entry); |
15dbf27c PZ |
8487 | } |
8488 | ||
a4eaf7f1 | 8489 | static void perf_swevent_start(struct perf_event *event, int flags) |
5c92d124 | 8490 | { |
a4eaf7f1 | 8491 | event->hw.state = 0; |
d6d020e9 | 8492 | } |
aa9c4c0f | 8493 | |
a4eaf7f1 | 8494 | static void perf_swevent_stop(struct perf_event *event, int flags) |
d6d020e9 | 8495 | { |
a4eaf7f1 | 8496 | event->hw.state = PERF_HES_STOPPED; |
bae43c99 IM |
8497 | } |
8498 | ||
49f135ed FW |
8499 | /* Deref the hlist from the update side */ |
8500 | static inline struct swevent_hlist * | |
b28ab83c | 8501 | swevent_hlist_deref(struct swevent_htable *swhash) |
49f135ed | 8502 | { |
b28ab83c PZ |
8503 | return rcu_dereference_protected(swhash->swevent_hlist, |
8504 | lockdep_is_held(&swhash->hlist_mutex)); | |
49f135ed FW |
8505 | } |
8506 | ||
b28ab83c | 8507 | static void swevent_hlist_release(struct swevent_htable *swhash) |
76e1d904 | 8508 | { |
b28ab83c | 8509 | struct swevent_hlist *hlist = swevent_hlist_deref(swhash); |
76e1d904 | 8510 | |
49f135ed | 8511 | if (!hlist) |
76e1d904 FW |
8512 | return; |
8513 | ||
70691d4a | 8514 | RCU_INIT_POINTER(swhash->swevent_hlist, NULL); |
fa4bbc4c | 8515 | kfree_rcu(hlist, rcu_head); |
76e1d904 FW |
8516 | } |
8517 | ||
3b364d7b | 8518 | static void swevent_hlist_put_cpu(int cpu) |
76e1d904 | 8519 | { |
b28ab83c | 8520 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 | 8521 | |
b28ab83c | 8522 | mutex_lock(&swhash->hlist_mutex); |
76e1d904 | 8523 | |
b28ab83c PZ |
8524 | if (!--swhash->hlist_refcount) |
8525 | swevent_hlist_release(swhash); | |
76e1d904 | 8526 | |
b28ab83c | 8527 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
8528 | } |
8529 | ||
3b364d7b | 8530 | static void swevent_hlist_put(void) |
76e1d904 FW |
8531 | { |
8532 | int cpu; | |
8533 | ||
76e1d904 | 8534 | for_each_possible_cpu(cpu) |
3b364d7b | 8535 | swevent_hlist_put_cpu(cpu); |
76e1d904 FW |
8536 | } |
8537 | ||
3b364d7b | 8538 | static int swevent_hlist_get_cpu(int cpu) |
76e1d904 | 8539 | { |
b28ab83c | 8540 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 FW |
8541 | int err = 0; |
8542 | ||
b28ab83c | 8543 | mutex_lock(&swhash->hlist_mutex); |
a63fbed7 TG |
8544 | if (!swevent_hlist_deref(swhash) && |
8545 | cpumask_test_cpu(cpu, perf_online_mask)) { | |
76e1d904 FW |
8546 | struct swevent_hlist *hlist; |
8547 | ||
8548 | hlist = kzalloc(sizeof(*hlist), GFP_KERNEL); | |
8549 | if (!hlist) { | |
8550 | err = -ENOMEM; | |
8551 | goto exit; | |
8552 | } | |
b28ab83c | 8553 | rcu_assign_pointer(swhash->swevent_hlist, hlist); |
76e1d904 | 8554 | } |
b28ab83c | 8555 | swhash->hlist_refcount++; |
9ed6060d | 8556 | exit: |
b28ab83c | 8557 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
8558 | |
8559 | return err; | |
8560 | } | |
8561 | ||
3b364d7b | 8562 | static int swevent_hlist_get(void) |
76e1d904 | 8563 | { |
3b364d7b | 8564 | int err, cpu, failed_cpu; |
76e1d904 | 8565 | |
a63fbed7 | 8566 | mutex_lock(&pmus_lock); |
76e1d904 | 8567 | for_each_possible_cpu(cpu) { |
3b364d7b | 8568 | err = swevent_hlist_get_cpu(cpu); |
76e1d904 FW |
8569 | if (err) { |
8570 | failed_cpu = cpu; | |
8571 | goto fail; | |
8572 | } | |
8573 | } | |
a63fbed7 | 8574 | mutex_unlock(&pmus_lock); |
76e1d904 | 8575 | return 0; |
9ed6060d | 8576 | fail: |
76e1d904 FW |
8577 | for_each_possible_cpu(cpu) { |
8578 | if (cpu == failed_cpu) | |
8579 | break; | |
3b364d7b | 8580 | swevent_hlist_put_cpu(cpu); |
76e1d904 | 8581 | } |
a63fbed7 | 8582 | mutex_unlock(&pmus_lock); |
76e1d904 FW |
8583 | return err; |
8584 | } | |
8585 | ||
c5905afb | 8586 | struct static_key perf_swevent_enabled[PERF_COUNT_SW_MAX]; |
95476b64 | 8587 | |
b0a873eb PZ |
8588 | static void sw_perf_event_destroy(struct perf_event *event) |
8589 | { | |
8590 | u64 event_id = event->attr.config; | |
95476b64 | 8591 | |
b0a873eb PZ |
8592 | WARN_ON(event->parent); |
8593 | ||
c5905afb | 8594 | static_key_slow_dec(&perf_swevent_enabled[event_id]); |
3b364d7b | 8595 | swevent_hlist_put(); |
b0a873eb PZ |
8596 | } |
8597 | ||
8598 | static int perf_swevent_init(struct perf_event *event) | |
8599 | { | |
8176cced | 8600 | u64 event_id = event->attr.config; |
b0a873eb PZ |
8601 | |
8602 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
8603 | return -ENOENT; | |
8604 | ||
2481c5fa SE |
8605 | /* |
8606 | * no branch sampling for software events | |
8607 | */ | |
8608 | if (has_branch_stack(event)) | |
8609 | return -EOPNOTSUPP; | |
8610 | ||
b0a873eb PZ |
8611 | switch (event_id) { |
8612 | case PERF_COUNT_SW_CPU_CLOCK: | |
8613 | case PERF_COUNT_SW_TASK_CLOCK: | |
8614 | return -ENOENT; | |
8615 | ||
8616 | default: | |
8617 | break; | |
8618 | } | |
8619 | ||
ce677831 | 8620 | if (event_id >= PERF_COUNT_SW_MAX) |
b0a873eb PZ |
8621 | return -ENOENT; |
8622 | ||
8623 | if (!event->parent) { | |
8624 | int err; | |
8625 | ||
3b364d7b | 8626 | err = swevent_hlist_get(); |
b0a873eb PZ |
8627 | if (err) |
8628 | return err; | |
8629 | ||
c5905afb | 8630 | static_key_slow_inc(&perf_swevent_enabled[event_id]); |
b0a873eb PZ |
8631 | event->destroy = sw_perf_event_destroy; |
8632 | } | |
8633 | ||
8634 | return 0; | |
8635 | } | |
8636 | ||
8637 | static struct pmu perf_swevent = { | |
89a1e187 | 8638 | .task_ctx_nr = perf_sw_context, |
95476b64 | 8639 | |
34f43927 PZ |
8640 | .capabilities = PERF_PMU_CAP_NO_NMI, |
8641 | ||
b0a873eb | 8642 | .event_init = perf_swevent_init, |
a4eaf7f1 PZ |
8643 | .add = perf_swevent_add, |
8644 | .del = perf_swevent_del, | |
8645 | .start = perf_swevent_start, | |
8646 | .stop = perf_swevent_stop, | |
1c024eca | 8647 | .read = perf_swevent_read, |
1c024eca PZ |
8648 | }; |
8649 | ||
b0a873eb PZ |
8650 | #ifdef CONFIG_EVENT_TRACING |
8651 | ||
1c024eca PZ |
8652 | static int perf_tp_filter_match(struct perf_event *event, |
8653 | struct perf_sample_data *data) | |
8654 | { | |
7e3f977e | 8655 | void *record = data->raw->frag.data; |
1c024eca | 8656 | |
b71b437e PZ |
8657 | /* only top level events have filters set */ |
8658 | if (event->parent) | |
8659 | event = event->parent; | |
8660 | ||
1c024eca PZ |
8661 | if (likely(!event->filter) || filter_match_preds(event->filter, record)) |
8662 | return 1; | |
8663 | return 0; | |
8664 | } | |
8665 | ||
8666 | static int perf_tp_event_match(struct perf_event *event, | |
8667 | struct perf_sample_data *data, | |
8668 | struct pt_regs *regs) | |
8669 | { | |
a0f7d0f7 FW |
8670 | if (event->hw.state & PERF_HES_STOPPED) |
8671 | return 0; | |
580d607c | 8672 | /* |
9fd2e48b | 8673 | * If exclude_kernel, only trace user-space tracepoints (uprobes) |
580d607c | 8674 | */ |
9fd2e48b | 8675 | if (event->attr.exclude_kernel && !user_mode(regs)) |
1c024eca PZ |
8676 | return 0; |
8677 | ||
8678 | if (!perf_tp_filter_match(event, data)) | |
8679 | return 0; | |
8680 | ||
8681 | return 1; | |
8682 | } | |
8683 | ||
85b67bcb AS |
8684 | void perf_trace_run_bpf_submit(void *raw_data, int size, int rctx, |
8685 | struct trace_event_call *call, u64 count, | |
8686 | struct pt_regs *regs, struct hlist_head *head, | |
8687 | struct task_struct *task) | |
8688 | { | |
e87c6bc3 | 8689 | if (bpf_prog_array_valid(call)) { |
85b67bcb | 8690 | *(struct pt_regs **)raw_data = regs; |
e87c6bc3 | 8691 | if (!trace_call_bpf(call, raw_data) || hlist_empty(head)) { |
85b67bcb AS |
8692 | perf_swevent_put_recursion_context(rctx); |
8693 | return; | |
8694 | } | |
8695 | } | |
8696 | perf_tp_event(call->event.type, count, raw_data, size, regs, head, | |
8fd0fbbe | 8697 | rctx, task); |
85b67bcb AS |
8698 | } |
8699 | EXPORT_SYMBOL_GPL(perf_trace_run_bpf_submit); | |
8700 | ||
1e1dcd93 | 8701 | void perf_tp_event(u16 event_type, u64 count, void *record, int entry_size, |
e6dab5ff | 8702 | struct pt_regs *regs, struct hlist_head *head, int rctx, |
8fd0fbbe | 8703 | struct task_struct *task) |
95476b64 FW |
8704 | { |
8705 | struct perf_sample_data data; | |
8fd0fbbe | 8706 | struct perf_event *event; |
1c024eca | 8707 | |
95476b64 | 8708 | struct perf_raw_record raw = { |
7e3f977e DB |
8709 | .frag = { |
8710 | .size = entry_size, | |
8711 | .data = record, | |
8712 | }, | |
95476b64 FW |
8713 | }; |
8714 | ||
1e1dcd93 | 8715 | perf_sample_data_init(&data, 0, 0); |
95476b64 FW |
8716 | data.raw = &raw; |
8717 | ||
1e1dcd93 AS |
8718 | perf_trace_buf_update(record, event_type); |
8719 | ||
8fd0fbbe | 8720 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
1c024eca | 8721 | if (perf_tp_event_match(event, &data, regs)) |
a8b0ca17 | 8722 | perf_swevent_event(event, count, &data, regs); |
4f41c013 | 8723 | } |
ecc55f84 | 8724 | |
e6dab5ff AV |
8725 | /* |
8726 | * If we got specified a target task, also iterate its context and | |
8727 | * deliver this event there too. | |
8728 | */ | |
8729 | if (task && task != current) { | |
8730 | struct perf_event_context *ctx; | |
8731 | struct trace_entry *entry = record; | |
8732 | ||
8733 | rcu_read_lock(); | |
8734 | ctx = rcu_dereference(task->perf_event_ctxp[perf_sw_context]); | |
8735 | if (!ctx) | |
8736 | goto unlock; | |
8737 | ||
8738 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
cd6fb677 JO |
8739 | if (event->cpu != smp_processor_id()) |
8740 | continue; | |
e6dab5ff AV |
8741 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
8742 | continue; | |
8743 | if (event->attr.config != entry->type) | |
8744 | continue; | |
8745 | if (perf_tp_event_match(event, &data, regs)) | |
8746 | perf_swevent_event(event, count, &data, regs); | |
8747 | } | |
8748 | unlock: | |
8749 | rcu_read_unlock(); | |
8750 | } | |
8751 | ||
ecc55f84 | 8752 | perf_swevent_put_recursion_context(rctx); |
95476b64 FW |
8753 | } |
8754 | EXPORT_SYMBOL_GPL(perf_tp_event); | |
8755 | ||
cdd6c482 | 8756 | static void tp_perf_event_destroy(struct perf_event *event) |
e077df4f | 8757 | { |
1c024eca | 8758 | perf_trace_destroy(event); |
e077df4f PZ |
8759 | } |
8760 | ||
b0a873eb | 8761 | static int perf_tp_event_init(struct perf_event *event) |
e077df4f | 8762 | { |
76e1d904 FW |
8763 | int err; |
8764 | ||
b0a873eb PZ |
8765 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
8766 | return -ENOENT; | |
8767 | ||
2481c5fa SE |
8768 | /* |
8769 | * no branch sampling for tracepoint events | |
8770 | */ | |
8771 | if (has_branch_stack(event)) | |
8772 | return -EOPNOTSUPP; | |
8773 | ||
1c024eca PZ |
8774 | err = perf_trace_init(event); |
8775 | if (err) | |
b0a873eb | 8776 | return err; |
e077df4f | 8777 | |
cdd6c482 | 8778 | event->destroy = tp_perf_event_destroy; |
e077df4f | 8779 | |
b0a873eb PZ |
8780 | return 0; |
8781 | } | |
8782 | ||
8783 | static struct pmu perf_tracepoint = { | |
89a1e187 PZ |
8784 | .task_ctx_nr = perf_sw_context, |
8785 | ||
b0a873eb | 8786 | .event_init = perf_tp_event_init, |
a4eaf7f1 PZ |
8787 | .add = perf_trace_add, |
8788 | .del = perf_trace_del, | |
8789 | .start = perf_swevent_start, | |
8790 | .stop = perf_swevent_stop, | |
b0a873eb | 8791 | .read = perf_swevent_read, |
b0a873eb PZ |
8792 | }; |
8793 | ||
33ea4b24 | 8794 | #if defined(CONFIG_KPROBE_EVENTS) || defined(CONFIG_UPROBE_EVENTS) |
e12f03d7 SL |
8795 | /* |
8796 | * Flags in config, used by dynamic PMU kprobe and uprobe | |
8797 | * The flags should match following PMU_FORMAT_ATTR(). | |
8798 | * | |
8799 | * PERF_PROBE_CONFIG_IS_RETPROBE if set, create kretprobe/uretprobe | |
8800 | * if not set, create kprobe/uprobe | |
a6ca88b2 SL |
8801 | * |
8802 | * The following values specify a reference counter (or semaphore in the | |
8803 | * terminology of tools like dtrace, systemtap, etc.) Userspace Statically | |
8804 | * Defined Tracepoints (USDT). Currently, we use 40 bit for the offset. | |
8805 | * | |
8806 | * PERF_UPROBE_REF_CTR_OFFSET_BITS # of bits in config as th offset | |
8807 | * PERF_UPROBE_REF_CTR_OFFSET_SHIFT # of bits to shift left | |
e12f03d7 SL |
8808 | */ |
8809 | enum perf_probe_config { | |
8810 | PERF_PROBE_CONFIG_IS_RETPROBE = 1U << 0, /* [k,u]retprobe */ | |
a6ca88b2 SL |
8811 | PERF_UPROBE_REF_CTR_OFFSET_BITS = 32, |
8812 | PERF_UPROBE_REF_CTR_OFFSET_SHIFT = 64 - PERF_UPROBE_REF_CTR_OFFSET_BITS, | |
e12f03d7 SL |
8813 | }; |
8814 | ||
8815 | PMU_FORMAT_ATTR(retprobe, "config:0"); | |
a6ca88b2 | 8816 | #endif |
e12f03d7 | 8817 | |
a6ca88b2 SL |
8818 | #ifdef CONFIG_KPROBE_EVENTS |
8819 | static struct attribute *kprobe_attrs[] = { | |
e12f03d7 SL |
8820 | &format_attr_retprobe.attr, |
8821 | NULL, | |
8822 | }; | |
8823 | ||
a6ca88b2 | 8824 | static struct attribute_group kprobe_format_group = { |
e12f03d7 | 8825 | .name = "format", |
a6ca88b2 | 8826 | .attrs = kprobe_attrs, |
e12f03d7 SL |
8827 | }; |
8828 | ||
a6ca88b2 SL |
8829 | static const struct attribute_group *kprobe_attr_groups[] = { |
8830 | &kprobe_format_group, | |
e12f03d7 SL |
8831 | NULL, |
8832 | }; | |
8833 | ||
8834 | static int perf_kprobe_event_init(struct perf_event *event); | |
8835 | static struct pmu perf_kprobe = { | |
8836 | .task_ctx_nr = perf_sw_context, | |
8837 | .event_init = perf_kprobe_event_init, | |
8838 | .add = perf_trace_add, | |
8839 | .del = perf_trace_del, | |
8840 | .start = perf_swevent_start, | |
8841 | .stop = perf_swevent_stop, | |
8842 | .read = perf_swevent_read, | |
a6ca88b2 | 8843 | .attr_groups = kprobe_attr_groups, |
e12f03d7 SL |
8844 | }; |
8845 | ||
8846 | static int perf_kprobe_event_init(struct perf_event *event) | |
8847 | { | |
8848 | int err; | |
8849 | bool is_retprobe; | |
8850 | ||
8851 | if (event->attr.type != perf_kprobe.type) | |
8852 | return -ENOENT; | |
32e6e967 SL |
8853 | |
8854 | if (!capable(CAP_SYS_ADMIN)) | |
8855 | return -EACCES; | |
8856 | ||
e12f03d7 SL |
8857 | /* |
8858 | * no branch sampling for probe events | |
8859 | */ | |
8860 | if (has_branch_stack(event)) | |
8861 | return -EOPNOTSUPP; | |
8862 | ||
8863 | is_retprobe = event->attr.config & PERF_PROBE_CONFIG_IS_RETPROBE; | |
8864 | err = perf_kprobe_init(event, is_retprobe); | |
8865 | if (err) | |
8866 | return err; | |
8867 | ||
8868 | event->destroy = perf_kprobe_destroy; | |
8869 | ||
8870 | return 0; | |
8871 | } | |
8872 | #endif /* CONFIG_KPROBE_EVENTS */ | |
8873 | ||
33ea4b24 | 8874 | #ifdef CONFIG_UPROBE_EVENTS |
a6ca88b2 SL |
8875 | PMU_FORMAT_ATTR(ref_ctr_offset, "config:32-63"); |
8876 | ||
8877 | static struct attribute *uprobe_attrs[] = { | |
8878 | &format_attr_retprobe.attr, | |
8879 | &format_attr_ref_ctr_offset.attr, | |
8880 | NULL, | |
8881 | }; | |
8882 | ||
8883 | static struct attribute_group uprobe_format_group = { | |
8884 | .name = "format", | |
8885 | .attrs = uprobe_attrs, | |
8886 | }; | |
8887 | ||
8888 | static const struct attribute_group *uprobe_attr_groups[] = { | |
8889 | &uprobe_format_group, | |
8890 | NULL, | |
8891 | }; | |
8892 | ||
33ea4b24 SL |
8893 | static int perf_uprobe_event_init(struct perf_event *event); |
8894 | static struct pmu perf_uprobe = { | |
8895 | .task_ctx_nr = perf_sw_context, | |
8896 | .event_init = perf_uprobe_event_init, | |
8897 | .add = perf_trace_add, | |
8898 | .del = perf_trace_del, | |
8899 | .start = perf_swevent_start, | |
8900 | .stop = perf_swevent_stop, | |
8901 | .read = perf_swevent_read, | |
a6ca88b2 | 8902 | .attr_groups = uprobe_attr_groups, |
33ea4b24 SL |
8903 | }; |
8904 | ||
8905 | static int perf_uprobe_event_init(struct perf_event *event) | |
8906 | { | |
8907 | int err; | |
a6ca88b2 | 8908 | unsigned long ref_ctr_offset; |
33ea4b24 SL |
8909 | bool is_retprobe; |
8910 | ||
8911 | if (event->attr.type != perf_uprobe.type) | |
8912 | return -ENOENT; | |
32e6e967 SL |
8913 | |
8914 | if (!capable(CAP_SYS_ADMIN)) | |
8915 | return -EACCES; | |
8916 | ||
33ea4b24 SL |
8917 | /* |
8918 | * no branch sampling for probe events | |
8919 | */ | |
8920 | if (has_branch_stack(event)) | |
8921 | return -EOPNOTSUPP; | |
8922 | ||
8923 | is_retprobe = event->attr.config & PERF_PROBE_CONFIG_IS_RETPROBE; | |
a6ca88b2 SL |
8924 | ref_ctr_offset = event->attr.config >> PERF_UPROBE_REF_CTR_OFFSET_SHIFT; |
8925 | err = perf_uprobe_init(event, ref_ctr_offset, is_retprobe); | |
33ea4b24 SL |
8926 | if (err) |
8927 | return err; | |
8928 | ||
8929 | event->destroy = perf_uprobe_destroy; | |
8930 | ||
8931 | return 0; | |
8932 | } | |
8933 | #endif /* CONFIG_UPROBE_EVENTS */ | |
8934 | ||
b0a873eb PZ |
8935 | static inline void perf_tp_register(void) |
8936 | { | |
2e80a82a | 8937 | perf_pmu_register(&perf_tracepoint, "tracepoint", PERF_TYPE_TRACEPOINT); |
e12f03d7 SL |
8938 | #ifdef CONFIG_KPROBE_EVENTS |
8939 | perf_pmu_register(&perf_kprobe, "kprobe", -1); | |
8940 | #endif | |
33ea4b24 SL |
8941 | #ifdef CONFIG_UPROBE_EVENTS |
8942 | perf_pmu_register(&perf_uprobe, "uprobe", -1); | |
8943 | #endif | |
e077df4f | 8944 | } |
6fb2915d | 8945 | |
6fb2915d LZ |
8946 | static void perf_event_free_filter(struct perf_event *event) |
8947 | { | |
8948 | ftrace_profile_free_filter(event); | |
8949 | } | |
8950 | ||
aa6a5f3c AS |
8951 | #ifdef CONFIG_BPF_SYSCALL |
8952 | static void bpf_overflow_handler(struct perf_event *event, | |
8953 | struct perf_sample_data *data, | |
8954 | struct pt_regs *regs) | |
8955 | { | |
8956 | struct bpf_perf_event_data_kern ctx = { | |
8957 | .data = data, | |
7d9285e8 | 8958 | .event = event, |
aa6a5f3c AS |
8959 | }; |
8960 | int ret = 0; | |
8961 | ||
c895f6f7 | 8962 | ctx.regs = perf_arch_bpf_user_pt_regs(regs); |
aa6a5f3c AS |
8963 | preempt_disable(); |
8964 | if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) | |
8965 | goto out; | |
8966 | rcu_read_lock(); | |
88575199 | 8967 | ret = BPF_PROG_RUN(event->prog, &ctx); |
aa6a5f3c AS |
8968 | rcu_read_unlock(); |
8969 | out: | |
8970 | __this_cpu_dec(bpf_prog_active); | |
8971 | preempt_enable(); | |
8972 | if (!ret) | |
8973 | return; | |
8974 | ||
8975 | event->orig_overflow_handler(event, data, regs); | |
8976 | } | |
8977 | ||
8978 | static int perf_event_set_bpf_handler(struct perf_event *event, u32 prog_fd) | |
8979 | { | |
8980 | struct bpf_prog *prog; | |
8981 | ||
8982 | if (event->overflow_handler_context) | |
8983 | /* hw breakpoint or kernel counter */ | |
8984 | return -EINVAL; | |
8985 | ||
8986 | if (event->prog) | |
8987 | return -EEXIST; | |
8988 | ||
8989 | prog = bpf_prog_get_type(prog_fd, BPF_PROG_TYPE_PERF_EVENT); | |
8990 | if (IS_ERR(prog)) | |
8991 | return PTR_ERR(prog); | |
8992 | ||
8993 | event->prog = prog; | |
8994 | event->orig_overflow_handler = READ_ONCE(event->overflow_handler); | |
8995 | WRITE_ONCE(event->overflow_handler, bpf_overflow_handler); | |
8996 | return 0; | |
8997 | } | |
8998 | ||
8999 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
9000 | { | |
9001 | struct bpf_prog *prog = event->prog; | |
9002 | ||
9003 | if (!prog) | |
9004 | return; | |
9005 | ||
9006 | WRITE_ONCE(event->overflow_handler, event->orig_overflow_handler); | |
9007 | event->prog = NULL; | |
9008 | bpf_prog_put(prog); | |
9009 | } | |
9010 | #else | |
9011 | static int perf_event_set_bpf_handler(struct perf_event *event, u32 prog_fd) | |
9012 | { | |
9013 | return -EOPNOTSUPP; | |
9014 | } | |
9015 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
9016 | { | |
9017 | } | |
9018 | #endif | |
9019 | ||
e12f03d7 SL |
9020 | /* |
9021 | * returns true if the event is a tracepoint, or a kprobe/upprobe created | |
9022 | * with perf_event_open() | |
9023 | */ | |
9024 | static inline bool perf_event_is_tracing(struct perf_event *event) | |
9025 | { | |
9026 | if (event->pmu == &perf_tracepoint) | |
9027 | return true; | |
9028 | #ifdef CONFIG_KPROBE_EVENTS | |
9029 | if (event->pmu == &perf_kprobe) | |
9030 | return true; | |
33ea4b24 SL |
9031 | #endif |
9032 | #ifdef CONFIG_UPROBE_EVENTS | |
9033 | if (event->pmu == &perf_uprobe) | |
9034 | return true; | |
e12f03d7 SL |
9035 | #endif |
9036 | return false; | |
9037 | } | |
9038 | ||
2541517c AS |
9039 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
9040 | { | |
cf5f5cea | 9041 | bool is_kprobe, is_tracepoint, is_syscall_tp; |
2541517c | 9042 | struct bpf_prog *prog; |
e87c6bc3 | 9043 | int ret; |
2541517c | 9044 | |
e12f03d7 | 9045 | if (!perf_event_is_tracing(event)) |
f91840a3 | 9046 | return perf_event_set_bpf_handler(event, prog_fd); |
2541517c | 9047 | |
98b5c2c6 AS |
9048 | is_kprobe = event->tp_event->flags & TRACE_EVENT_FL_UKPROBE; |
9049 | is_tracepoint = event->tp_event->flags & TRACE_EVENT_FL_TRACEPOINT; | |
cf5f5cea YS |
9050 | is_syscall_tp = is_syscall_trace_event(event->tp_event); |
9051 | if (!is_kprobe && !is_tracepoint && !is_syscall_tp) | |
98b5c2c6 | 9052 | /* bpf programs can only be attached to u/kprobe or tracepoint */ |
2541517c AS |
9053 | return -EINVAL; |
9054 | ||
9055 | prog = bpf_prog_get(prog_fd); | |
9056 | if (IS_ERR(prog)) | |
9057 | return PTR_ERR(prog); | |
9058 | ||
98b5c2c6 | 9059 | if ((is_kprobe && prog->type != BPF_PROG_TYPE_KPROBE) || |
cf5f5cea YS |
9060 | (is_tracepoint && prog->type != BPF_PROG_TYPE_TRACEPOINT) || |
9061 | (is_syscall_tp && prog->type != BPF_PROG_TYPE_TRACEPOINT)) { | |
2541517c AS |
9062 | /* valid fd, but invalid bpf program type */ |
9063 | bpf_prog_put(prog); | |
9064 | return -EINVAL; | |
9065 | } | |
9066 | ||
9802d865 JB |
9067 | /* Kprobe override only works for kprobes, not uprobes. */ |
9068 | if (prog->kprobe_override && | |
9069 | !(event->tp_event->flags & TRACE_EVENT_FL_KPROBE)) { | |
9070 | bpf_prog_put(prog); | |
9071 | return -EINVAL; | |
9072 | } | |
9073 | ||
cf5f5cea | 9074 | if (is_tracepoint || is_syscall_tp) { |
32bbe007 AS |
9075 | int off = trace_event_get_offsets(event->tp_event); |
9076 | ||
9077 | if (prog->aux->max_ctx_offset > off) { | |
9078 | bpf_prog_put(prog); | |
9079 | return -EACCES; | |
9080 | } | |
9081 | } | |
2541517c | 9082 | |
e87c6bc3 YS |
9083 | ret = perf_event_attach_bpf_prog(event, prog); |
9084 | if (ret) | |
9085 | bpf_prog_put(prog); | |
9086 | return ret; | |
2541517c AS |
9087 | } |
9088 | ||
9089 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
9090 | { | |
e12f03d7 | 9091 | if (!perf_event_is_tracing(event)) { |
0b4c6841 | 9092 | perf_event_free_bpf_handler(event); |
2541517c | 9093 | return; |
2541517c | 9094 | } |
e87c6bc3 | 9095 | perf_event_detach_bpf_prog(event); |
2541517c AS |
9096 | } |
9097 | ||
e077df4f | 9098 | #else |
6fb2915d | 9099 | |
b0a873eb | 9100 | static inline void perf_tp_register(void) |
e077df4f | 9101 | { |
e077df4f | 9102 | } |
6fb2915d | 9103 | |
6fb2915d LZ |
9104 | static void perf_event_free_filter(struct perf_event *event) |
9105 | { | |
9106 | } | |
9107 | ||
2541517c AS |
9108 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
9109 | { | |
9110 | return -ENOENT; | |
9111 | } | |
9112 | ||
9113 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
9114 | { | |
9115 | } | |
07b139c8 | 9116 | #endif /* CONFIG_EVENT_TRACING */ |
e077df4f | 9117 | |
24f1e32c | 9118 | #ifdef CONFIG_HAVE_HW_BREAKPOINT |
f5ffe02e | 9119 | void perf_bp_event(struct perf_event *bp, void *data) |
24f1e32c | 9120 | { |
f5ffe02e FW |
9121 | struct perf_sample_data sample; |
9122 | struct pt_regs *regs = data; | |
9123 | ||
fd0d000b | 9124 | perf_sample_data_init(&sample, bp->attr.bp_addr, 0); |
f5ffe02e | 9125 | |
a4eaf7f1 | 9126 | if (!bp->hw.state && !perf_exclude_event(bp, regs)) |
a8b0ca17 | 9127 | perf_swevent_event(bp, 1, &sample, regs); |
24f1e32c FW |
9128 | } |
9129 | #endif | |
9130 | ||
375637bc AS |
9131 | /* |
9132 | * Allocate a new address filter | |
9133 | */ | |
9134 | static struct perf_addr_filter * | |
9135 | perf_addr_filter_new(struct perf_event *event, struct list_head *filters) | |
9136 | { | |
9137 | int node = cpu_to_node(event->cpu == -1 ? 0 : event->cpu); | |
9138 | struct perf_addr_filter *filter; | |
9139 | ||
9140 | filter = kzalloc_node(sizeof(*filter), GFP_KERNEL, node); | |
9141 | if (!filter) | |
9142 | return NULL; | |
9143 | ||
9144 | INIT_LIST_HEAD(&filter->entry); | |
9145 | list_add_tail(&filter->entry, filters); | |
9146 | ||
9147 | return filter; | |
9148 | } | |
9149 | ||
9150 | static void free_filters_list(struct list_head *filters) | |
9151 | { | |
9152 | struct perf_addr_filter *filter, *iter; | |
9153 | ||
9154 | list_for_each_entry_safe(filter, iter, filters, entry) { | |
9511bce9 | 9155 | path_put(&filter->path); |
375637bc AS |
9156 | list_del(&filter->entry); |
9157 | kfree(filter); | |
9158 | } | |
9159 | } | |
9160 | ||
9161 | /* | |
9162 | * Free existing address filters and optionally install new ones | |
9163 | */ | |
9164 | static void perf_addr_filters_splice(struct perf_event *event, | |
9165 | struct list_head *head) | |
9166 | { | |
9167 | unsigned long flags; | |
9168 | LIST_HEAD(list); | |
9169 | ||
9170 | if (!has_addr_filter(event)) | |
9171 | return; | |
9172 | ||
9173 | /* don't bother with children, they don't have their own filters */ | |
9174 | if (event->parent) | |
9175 | return; | |
9176 | ||
9177 | raw_spin_lock_irqsave(&event->addr_filters.lock, flags); | |
9178 | ||
9179 | list_splice_init(&event->addr_filters.list, &list); | |
9180 | if (head) | |
9181 | list_splice(head, &event->addr_filters.list); | |
9182 | ||
9183 | raw_spin_unlock_irqrestore(&event->addr_filters.lock, flags); | |
9184 | ||
9185 | free_filters_list(&list); | |
9186 | } | |
9187 | ||
9188 | /* | |
9189 | * Scan through mm's vmas and see if one of them matches the | |
9190 | * @filter; if so, adjust filter's address range. | |
9191 | * Called with mm::mmap_sem down for reading. | |
9192 | */ | |
c60f83b8 AS |
9193 | static void perf_addr_filter_apply(struct perf_addr_filter *filter, |
9194 | struct mm_struct *mm, | |
9195 | struct perf_addr_filter_range *fr) | |
375637bc AS |
9196 | { |
9197 | struct vm_area_struct *vma; | |
9198 | ||
9199 | for (vma = mm->mmap; vma; vma = vma->vm_next) { | |
c60f83b8 | 9200 | if (!vma->vm_file) |
375637bc AS |
9201 | continue; |
9202 | ||
c60f83b8 AS |
9203 | if (perf_addr_filter_vma_adjust(filter, vma, fr)) |
9204 | return; | |
375637bc | 9205 | } |
375637bc AS |
9206 | } |
9207 | ||
9208 | /* | |
9209 | * Update event's address range filters based on the | |
9210 | * task's existing mappings, if any. | |
9211 | */ | |
9212 | static void perf_event_addr_filters_apply(struct perf_event *event) | |
9213 | { | |
9214 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
9215 | struct task_struct *task = READ_ONCE(event->ctx->task); | |
9216 | struct perf_addr_filter *filter; | |
9217 | struct mm_struct *mm = NULL; | |
9218 | unsigned int count = 0; | |
9219 | unsigned long flags; | |
9220 | ||
9221 | /* | |
9222 | * We may observe TASK_TOMBSTONE, which means that the event tear-down | |
9223 | * will stop on the parent's child_mutex that our caller is also holding | |
9224 | */ | |
9225 | if (task == TASK_TOMBSTONE) | |
9226 | return; | |
9227 | ||
52a44f83 AS |
9228 | if (ifh->nr_file_filters) { |
9229 | mm = get_task_mm(event->ctx->task); | |
9230 | if (!mm) | |
9231 | goto restart; | |
375637bc | 9232 | |
52a44f83 AS |
9233 | down_read(&mm->mmap_sem); |
9234 | } | |
375637bc AS |
9235 | |
9236 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
9237 | list_for_each_entry(filter, &ifh->list, entry) { | |
52a44f83 AS |
9238 | if (filter->path.dentry) { |
9239 | /* | |
9240 | * Adjust base offset if the filter is associated to a | |
9241 | * binary that needs to be mapped: | |
9242 | */ | |
9243 | event->addr_filter_ranges[count].start = 0; | |
9244 | event->addr_filter_ranges[count].size = 0; | |
375637bc | 9245 | |
c60f83b8 | 9246 | perf_addr_filter_apply(filter, mm, &event->addr_filter_ranges[count]); |
52a44f83 AS |
9247 | } else { |
9248 | event->addr_filter_ranges[count].start = filter->offset; | |
9249 | event->addr_filter_ranges[count].size = filter->size; | |
9250 | } | |
375637bc AS |
9251 | |
9252 | count++; | |
9253 | } | |
9254 | ||
9255 | event->addr_filters_gen++; | |
9256 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
9257 | ||
52a44f83 AS |
9258 | if (ifh->nr_file_filters) { |
9259 | up_read(&mm->mmap_sem); | |
375637bc | 9260 | |
52a44f83 AS |
9261 | mmput(mm); |
9262 | } | |
375637bc AS |
9263 | |
9264 | restart: | |
767ae086 | 9265 | perf_event_stop(event, 1); |
375637bc AS |
9266 | } |
9267 | ||
9268 | /* | |
9269 | * Address range filtering: limiting the data to certain | |
9270 | * instruction address ranges. Filters are ioctl()ed to us from | |
9271 | * userspace as ascii strings. | |
9272 | * | |
9273 | * Filter string format: | |
9274 | * | |
9275 | * ACTION RANGE_SPEC | |
9276 | * where ACTION is one of the | |
9277 | * * "filter": limit the trace to this region | |
9278 | * * "start": start tracing from this address | |
9279 | * * "stop": stop tracing at this address/region; | |
9280 | * RANGE_SPEC is | |
9281 | * * for kernel addresses: <start address>[/<size>] | |
9282 | * * for object files: <start address>[/<size>]@</path/to/object/file> | |
9283 | * | |
6ed70cf3 AS |
9284 | * if <size> is not specified or is zero, the range is treated as a single |
9285 | * address; not valid for ACTION=="filter". | |
375637bc AS |
9286 | */ |
9287 | enum { | |
e96271f3 | 9288 | IF_ACT_NONE = -1, |
375637bc AS |
9289 | IF_ACT_FILTER, |
9290 | IF_ACT_START, | |
9291 | IF_ACT_STOP, | |
9292 | IF_SRC_FILE, | |
9293 | IF_SRC_KERNEL, | |
9294 | IF_SRC_FILEADDR, | |
9295 | IF_SRC_KERNELADDR, | |
9296 | }; | |
9297 | ||
9298 | enum { | |
9299 | IF_STATE_ACTION = 0, | |
9300 | IF_STATE_SOURCE, | |
9301 | IF_STATE_END, | |
9302 | }; | |
9303 | ||
9304 | static const match_table_t if_tokens = { | |
9305 | { IF_ACT_FILTER, "filter" }, | |
9306 | { IF_ACT_START, "start" }, | |
9307 | { IF_ACT_STOP, "stop" }, | |
9308 | { IF_SRC_FILE, "%u/%u@%s" }, | |
9309 | { IF_SRC_KERNEL, "%u/%u" }, | |
9310 | { IF_SRC_FILEADDR, "%u@%s" }, | |
9311 | { IF_SRC_KERNELADDR, "%u" }, | |
e96271f3 | 9312 | { IF_ACT_NONE, NULL }, |
375637bc AS |
9313 | }; |
9314 | ||
9315 | /* | |
9316 | * Address filter string parser | |
9317 | */ | |
9318 | static int | |
9319 | perf_event_parse_addr_filter(struct perf_event *event, char *fstr, | |
9320 | struct list_head *filters) | |
9321 | { | |
9322 | struct perf_addr_filter *filter = NULL; | |
9323 | char *start, *orig, *filename = NULL; | |
375637bc AS |
9324 | substring_t args[MAX_OPT_ARGS]; |
9325 | int state = IF_STATE_ACTION, token; | |
9326 | unsigned int kernel = 0; | |
9327 | int ret = -EINVAL; | |
9328 | ||
9329 | orig = fstr = kstrdup(fstr, GFP_KERNEL); | |
9330 | if (!fstr) | |
9331 | return -ENOMEM; | |
9332 | ||
9333 | while ((start = strsep(&fstr, " ,\n")) != NULL) { | |
6ed70cf3 AS |
9334 | static const enum perf_addr_filter_action_t actions[] = { |
9335 | [IF_ACT_FILTER] = PERF_ADDR_FILTER_ACTION_FILTER, | |
9336 | [IF_ACT_START] = PERF_ADDR_FILTER_ACTION_START, | |
9337 | [IF_ACT_STOP] = PERF_ADDR_FILTER_ACTION_STOP, | |
9338 | }; | |
375637bc AS |
9339 | ret = -EINVAL; |
9340 | ||
9341 | if (!*start) | |
9342 | continue; | |
9343 | ||
9344 | /* filter definition begins */ | |
9345 | if (state == IF_STATE_ACTION) { | |
9346 | filter = perf_addr_filter_new(event, filters); | |
9347 | if (!filter) | |
9348 | goto fail; | |
9349 | } | |
9350 | ||
9351 | token = match_token(start, if_tokens, args); | |
9352 | switch (token) { | |
9353 | case IF_ACT_FILTER: | |
9354 | case IF_ACT_START: | |
375637bc AS |
9355 | case IF_ACT_STOP: |
9356 | if (state != IF_STATE_ACTION) | |
9357 | goto fail; | |
9358 | ||
6ed70cf3 | 9359 | filter->action = actions[token]; |
375637bc AS |
9360 | state = IF_STATE_SOURCE; |
9361 | break; | |
9362 | ||
9363 | case IF_SRC_KERNELADDR: | |
9364 | case IF_SRC_KERNEL: | |
9365 | kernel = 1; | |
10c3405f | 9366 | /* fall through */ |
375637bc AS |
9367 | |
9368 | case IF_SRC_FILEADDR: | |
9369 | case IF_SRC_FILE: | |
9370 | if (state != IF_STATE_SOURCE) | |
9371 | goto fail; | |
9372 | ||
375637bc AS |
9373 | *args[0].to = 0; |
9374 | ret = kstrtoul(args[0].from, 0, &filter->offset); | |
9375 | if (ret) | |
9376 | goto fail; | |
9377 | ||
6ed70cf3 | 9378 | if (token == IF_SRC_KERNEL || token == IF_SRC_FILE) { |
375637bc AS |
9379 | *args[1].to = 0; |
9380 | ret = kstrtoul(args[1].from, 0, &filter->size); | |
9381 | if (ret) | |
9382 | goto fail; | |
9383 | } | |
9384 | ||
4059ffd0 | 9385 | if (token == IF_SRC_FILE || token == IF_SRC_FILEADDR) { |
6ed70cf3 | 9386 | int fpos = token == IF_SRC_FILE ? 2 : 1; |
4059ffd0 MP |
9387 | |
9388 | filename = match_strdup(&args[fpos]); | |
375637bc AS |
9389 | if (!filename) { |
9390 | ret = -ENOMEM; | |
9391 | goto fail; | |
9392 | } | |
9393 | } | |
9394 | ||
9395 | state = IF_STATE_END; | |
9396 | break; | |
9397 | ||
9398 | default: | |
9399 | goto fail; | |
9400 | } | |
9401 | ||
9402 | /* | |
9403 | * Filter definition is fully parsed, validate and install it. | |
9404 | * Make sure that it doesn't contradict itself or the event's | |
9405 | * attribute. | |
9406 | */ | |
9407 | if (state == IF_STATE_END) { | |
9ccbfbb1 | 9408 | ret = -EINVAL; |
375637bc AS |
9409 | if (kernel && event->attr.exclude_kernel) |
9410 | goto fail; | |
9411 | ||
6ed70cf3 AS |
9412 | /* |
9413 | * ACTION "filter" must have a non-zero length region | |
9414 | * specified. | |
9415 | */ | |
9416 | if (filter->action == PERF_ADDR_FILTER_ACTION_FILTER && | |
9417 | !filter->size) | |
9418 | goto fail; | |
9419 | ||
375637bc AS |
9420 | if (!kernel) { |
9421 | if (!filename) | |
9422 | goto fail; | |
9423 | ||
6ce77bfd AS |
9424 | /* |
9425 | * For now, we only support file-based filters | |
9426 | * in per-task events; doing so for CPU-wide | |
9427 | * events requires additional context switching | |
9428 | * trickery, since same object code will be | |
9429 | * mapped at different virtual addresses in | |
9430 | * different processes. | |
9431 | */ | |
9432 | ret = -EOPNOTSUPP; | |
9433 | if (!event->ctx->task) | |
9434 | goto fail_free_name; | |
9435 | ||
375637bc | 9436 | /* look up the path and grab its inode */ |
9511bce9 SL |
9437 | ret = kern_path(filename, LOOKUP_FOLLOW, |
9438 | &filter->path); | |
375637bc AS |
9439 | if (ret) |
9440 | goto fail_free_name; | |
9441 | ||
375637bc AS |
9442 | kfree(filename); |
9443 | filename = NULL; | |
9444 | ||
9445 | ret = -EINVAL; | |
9511bce9 SL |
9446 | if (!filter->path.dentry || |
9447 | !S_ISREG(d_inode(filter->path.dentry) | |
9448 | ->i_mode)) | |
375637bc | 9449 | goto fail; |
6ce77bfd AS |
9450 | |
9451 | event->addr_filters.nr_file_filters++; | |
375637bc AS |
9452 | } |
9453 | ||
9454 | /* ready to consume more filters */ | |
9455 | state = IF_STATE_ACTION; | |
9456 | filter = NULL; | |
9457 | } | |
9458 | } | |
9459 | ||
9460 | if (state != IF_STATE_ACTION) | |
9461 | goto fail; | |
9462 | ||
9463 | kfree(orig); | |
9464 | ||
9465 | return 0; | |
9466 | ||
9467 | fail_free_name: | |
9468 | kfree(filename); | |
9469 | fail: | |
9470 | free_filters_list(filters); | |
9471 | kfree(orig); | |
9472 | ||
9473 | return ret; | |
9474 | } | |
9475 | ||
9476 | static int | |
9477 | perf_event_set_addr_filter(struct perf_event *event, char *filter_str) | |
9478 | { | |
9479 | LIST_HEAD(filters); | |
9480 | int ret; | |
9481 | ||
9482 | /* | |
9483 | * Since this is called in perf_ioctl() path, we're already holding | |
9484 | * ctx::mutex. | |
9485 | */ | |
9486 | lockdep_assert_held(&event->ctx->mutex); | |
9487 | ||
9488 | if (WARN_ON_ONCE(event->parent)) | |
9489 | return -EINVAL; | |
9490 | ||
375637bc AS |
9491 | ret = perf_event_parse_addr_filter(event, filter_str, &filters); |
9492 | if (ret) | |
6ce77bfd | 9493 | goto fail_clear_files; |
375637bc AS |
9494 | |
9495 | ret = event->pmu->addr_filters_validate(&filters); | |
6ce77bfd AS |
9496 | if (ret) |
9497 | goto fail_free_filters; | |
375637bc AS |
9498 | |
9499 | /* remove existing filters, if any */ | |
9500 | perf_addr_filters_splice(event, &filters); | |
9501 | ||
9502 | /* install new filters */ | |
9503 | perf_event_for_each_child(event, perf_event_addr_filters_apply); | |
9504 | ||
6ce77bfd AS |
9505 | return ret; |
9506 | ||
9507 | fail_free_filters: | |
9508 | free_filters_list(&filters); | |
9509 | ||
9510 | fail_clear_files: | |
9511 | event->addr_filters.nr_file_filters = 0; | |
9512 | ||
375637bc AS |
9513 | return ret; |
9514 | } | |
9515 | ||
c796bbbe AS |
9516 | static int perf_event_set_filter(struct perf_event *event, void __user *arg) |
9517 | { | |
c796bbbe | 9518 | int ret = -EINVAL; |
e12f03d7 | 9519 | char *filter_str; |
c796bbbe AS |
9520 | |
9521 | filter_str = strndup_user(arg, PAGE_SIZE); | |
9522 | if (IS_ERR(filter_str)) | |
9523 | return PTR_ERR(filter_str); | |
9524 | ||
e12f03d7 SL |
9525 | #ifdef CONFIG_EVENT_TRACING |
9526 | if (perf_event_is_tracing(event)) { | |
9527 | struct perf_event_context *ctx = event->ctx; | |
9528 | ||
9529 | /* | |
9530 | * Beware, here be dragons!! | |
9531 | * | |
9532 | * the tracepoint muck will deadlock against ctx->mutex, but | |
9533 | * the tracepoint stuff does not actually need it. So | |
9534 | * temporarily drop ctx->mutex. As per perf_event_ctx_lock() we | |
9535 | * already have a reference on ctx. | |
9536 | * | |
9537 | * This can result in event getting moved to a different ctx, | |
9538 | * but that does not affect the tracepoint state. | |
9539 | */ | |
9540 | mutex_unlock(&ctx->mutex); | |
9541 | ret = ftrace_profile_set_filter(event, event->attr.config, filter_str); | |
9542 | mutex_lock(&ctx->mutex); | |
9543 | } else | |
9544 | #endif | |
9545 | if (has_addr_filter(event)) | |
375637bc | 9546 | ret = perf_event_set_addr_filter(event, filter_str); |
c796bbbe AS |
9547 | |
9548 | kfree(filter_str); | |
9549 | return ret; | |
9550 | } | |
9551 | ||
b0a873eb PZ |
9552 | /* |
9553 | * hrtimer based swevent callback | |
9554 | */ | |
f29ac756 | 9555 | |
b0a873eb | 9556 | static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer) |
f29ac756 | 9557 | { |
b0a873eb PZ |
9558 | enum hrtimer_restart ret = HRTIMER_RESTART; |
9559 | struct perf_sample_data data; | |
9560 | struct pt_regs *regs; | |
9561 | struct perf_event *event; | |
9562 | u64 period; | |
f29ac756 | 9563 | |
b0a873eb | 9564 | event = container_of(hrtimer, struct perf_event, hw.hrtimer); |
ba3dd36c PZ |
9565 | |
9566 | if (event->state != PERF_EVENT_STATE_ACTIVE) | |
9567 | return HRTIMER_NORESTART; | |
9568 | ||
b0a873eb | 9569 | event->pmu->read(event); |
f344011c | 9570 | |
fd0d000b | 9571 | perf_sample_data_init(&data, 0, event->hw.last_period); |
b0a873eb PZ |
9572 | regs = get_irq_regs(); |
9573 | ||
9574 | if (regs && !perf_exclude_event(event, regs)) { | |
77aeeebd | 9575 | if (!(event->attr.exclude_idle && is_idle_task(current))) |
33b07b8b | 9576 | if (__perf_event_overflow(event, 1, &data, regs)) |
b0a873eb PZ |
9577 | ret = HRTIMER_NORESTART; |
9578 | } | |
24f1e32c | 9579 | |
b0a873eb PZ |
9580 | period = max_t(u64, 10000, event->hw.sample_period); |
9581 | hrtimer_forward_now(hrtimer, ns_to_ktime(period)); | |
24f1e32c | 9582 | |
b0a873eb | 9583 | return ret; |
f29ac756 PZ |
9584 | } |
9585 | ||
b0a873eb | 9586 | static void perf_swevent_start_hrtimer(struct perf_event *event) |
5c92d124 | 9587 | { |
b0a873eb | 9588 | struct hw_perf_event *hwc = &event->hw; |
5d508e82 FBH |
9589 | s64 period; |
9590 | ||
9591 | if (!is_sampling_event(event)) | |
9592 | return; | |
f5ffe02e | 9593 | |
5d508e82 FBH |
9594 | period = local64_read(&hwc->period_left); |
9595 | if (period) { | |
9596 | if (period < 0) | |
9597 | period = 10000; | |
fa407f35 | 9598 | |
5d508e82 FBH |
9599 | local64_set(&hwc->period_left, 0); |
9600 | } else { | |
9601 | period = max_t(u64, 10000, hwc->sample_period); | |
9602 | } | |
3497d206 | 9603 | hrtimer_start(&hwc->hrtimer, ns_to_ktime(period), |
30f9028b | 9604 | HRTIMER_MODE_REL_PINNED_HARD); |
24f1e32c | 9605 | } |
b0a873eb PZ |
9606 | |
9607 | static void perf_swevent_cancel_hrtimer(struct perf_event *event) | |
24f1e32c | 9608 | { |
b0a873eb PZ |
9609 | struct hw_perf_event *hwc = &event->hw; |
9610 | ||
6c7e550f | 9611 | if (is_sampling_event(event)) { |
b0a873eb | 9612 | ktime_t remaining = hrtimer_get_remaining(&hwc->hrtimer); |
fa407f35 | 9613 | local64_set(&hwc->period_left, ktime_to_ns(remaining)); |
b0a873eb PZ |
9614 | |
9615 | hrtimer_cancel(&hwc->hrtimer); | |
9616 | } | |
24f1e32c FW |
9617 | } |
9618 | ||
ba3dd36c PZ |
9619 | static void perf_swevent_init_hrtimer(struct perf_event *event) |
9620 | { | |
9621 | struct hw_perf_event *hwc = &event->hw; | |
9622 | ||
9623 | if (!is_sampling_event(event)) | |
9624 | return; | |
9625 | ||
30f9028b | 9626 | hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_HARD); |
ba3dd36c PZ |
9627 | hwc->hrtimer.function = perf_swevent_hrtimer; |
9628 | ||
9629 | /* | |
9630 | * Since hrtimers have a fixed rate, we can do a static freq->period | |
9631 | * mapping and avoid the whole period adjust feedback stuff. | |
9632 | */ | |
9633 | if (event->attr.freq) { | |
9634 | long freq = event->attr.sample_freq; | |
9635 | ||
9636 | event->attr.sample_period = NSEC_PER_SEC / freq; | |
9637 | hwc->sample_period = event->attr.sample_period; | |
9638 | local64_set(&hwc->period_left, hwc->sample_period); | |
778141e3 | 9639 | hwc->last_period = hwc->sample_period; |
ba3dd36c PZ |
9640 | event->attr.freq = 0; |
9641 | } | |
9642 | } | |
9643 | ||
b0a873eb PZ |
9644 | /* |
9645 | * Software event: cpu wall time clock | |
9646 | */ | |
9647 | ||
9648 | static void cpu_clock_event_update(struct perf_event *event) | |
24f1e32c | 9649 | { |
b0a873eb PZ |
9650 | s64 prev; |
9651 | u64 now; | |
9652 | ||
a4eaf7f1 | 9653 | now = local_clock(); |
b0a873eb PZ |
9654 | prev = local64_xchg(&event->hw.prev_count, now); |
9655 | local64_add(now - prev, &event->count); | |
24f1e32c | 9656 | } |
24f1e32c | 9657 | |
a4eaf7f1 | 9658 | static void cpu_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 9659 | { |
a4eaf7f1 | 9660 | local64_set(&event->hw.prev_count, local_clock()); |
b0a873eb | 9661 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
9662 | } |
9663 | ||
a4eaf7f1 | 9664 | static void cpu_clock_event_stop(struct perf_event *event, int flags) |
f29ac756 | 9665 | { |
b0a873eb PZ |
9666 | perf_swevent_cancel_hrtimer(event); |
9667 | cpu_clock_event_update(event); | |
9668 | } | |
f29ac756 | 9669 | |
a4eaf7f1 PZ |
9670 | static int cpu_clock_event_add(struct perf_event *event, int flags) |
9671 | { | |
9672 | if (flags & PERF_EF_START) | |
9673 | cpu_clock_event_start(event, flags); | |
6a694a60 | 9674 | perf_event_update_userpage(event); |
a4eaf7f1 PZ |
9675 | |
9676 | return 0; | |
9677 | } | |
9678 | ||
9679 | static void cpu_clock_event_del(struct perf_event *event, int flags) | |
9680 | { | |
9681 | cpu_clock_event_stop(event, flags); | |
9682 | } | |
9683 | ||
b0a873eb PZ |
9684 | static void cpu_clock_event_read(struct perf_event *event) |
9685 | { | |
9686 | cpu_clock_event_update(event); | |
9687 | } | |
f344011c | 9688 | |
b0a873eb PZ |
9689 | static int cpu_clock_event_init(struct perf_event *event) |
9690 | { | |
9691 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
9692 | return -ENOENT; | |
9693 | ||
9694 | if (event->attr.config != PERF_COUNT_SW_CPU_CLOCK) | |
9695 | return -ENOENT; | |
9696 | ||
2481c5fa SE |
9697 | /* |
9698 | * no branch sampling for software events | |
9699 | */ | |
9700 | if (has_branch_stack(event)) | |
9701 | return -EOPNOTSUPP; | |
9702 | ||
ba3dd36c PZ |
9703 | perf_swevent_init_hrtimer(event); |
9704 | ||
b0a873eb | 9705 | return 0; |
f29ac756 PZ |
9706 | } |
9707 | ||
b0a873eb | 9708 | static struct pmu perf_cpu_clock = { |
89a1e187 PZ |
9709 | .task_ctx_nr = perf_sw_context, |
9710 | ||
34f43927 PZ |
9711 | .capabilities = PERF_PMU_CAP_NO_NMI, |
9712 | ||
b0a873eb | 9713 | .event_init = cpu_clock_event_init, |
a4eaf7f1 PZ |
9714 | .add = cpu_clock_event_add, |
9715 | .del = cpu_clock_event_del, | |
9716 | .start = cpu_clock_event_start, | |
9717 | .stop = cpu_clock_event_stop, | |
b0a873eb PZ |
9718 | .read = cpu_clock_event_read, |
9719 | }; | |
9720 | ||
9721 | /* | |
9722 | * Software event: task time clock | |
9723 | */ | |
9724 | ||
9725 | static void task_clock_event_update(struct perf_event *event, u64 now) | |
5c92d124 | 9726 | { |
b0a873eb PZ |
9727 | u64 prev; |
9728 | s64 delta; | |
5c92d124 | 9729 | |
b0a873eb PZ |
9730 | prev = local64_xchg(&event->hw.prev_count, now); |
9731 | delta = now - prev; | |
9732 | local64_add(delta, &event->count); | |
9733 | } | |
5c92d124 | 9734 | |
a4eaf7f1 | 9735 | static void task_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 9736 | { |
a4eaf7f1 | 9737 | local64_set(&event->hw.prev_count, event->ctx->time); |
b0a873eb | 9738 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
9739 | } |
9740 | ||
a4eaf7f1 | 9741 | static void task_clock_event_stop(struct perf_event *event, int flags) |
b0a873eb PZ |
9742 | { |
9743 | perf_swevent_cancel_hrtimer(event); | |
9744 | task_clock_event_update(event, event->ctx->time); | |
a4eaf7f1 PZ |
9745 | } |
9746 | ||
9747 | static int task_clock_event_add(struct perf_event *event, int flags) | |
9748 | { | |
9749 | if (flags & PERF_EF_START) | |
9750 | task_clock_event_start(event, flags); | |
6a694a60 | 9751 | perf_event_update_userpage(event); |
b0a873eb | 9752 | |
a4eaf7f1 PZ |
9753 | return 0; |
9754 | } | |
9755 | ||
9756 | static void task_clock_event_del(struct perf_event *event, int flags) | |
9757 | { | |
9758 | task_clock_event_stop(event, PERF_EF_UPDATE); | |
b0a873eb PZ |
9759 | } |
9760 | ||
9761 | static void task_clock_event_read(struct perf_event *event) | |
9762 | { | |
768a06e2 PZ |
9763 | u64 now = perf_clock(); |
9764 | u64 delta = now - event->ctx->timestamp; | |
9765 | u64 time = event->ctx->time + delta; | |
b0a873eb PZ |
9766 | |
9767 | task_clock_event_update(event, time); | |
9768 | } | |
9769 | ||
9770 | static int task_clock_event_init(struct perf_event *event) | |
6fb2915d | 9771 | { |
b0a873eb PZ |
9772 | if (event->attr.type != PERF_TYPE_SOFTWARE) |
9773 | return -ENOENT; | |
9774 | ||
9775 | if (event->attr.config != PERF_COUNT_SW_TASK_CLOCK) | |
9776 | return -ENOENT; | |
9777 | ||
2481c5fa SE |
9778 | /* |
9779 | * no branch sampling for software events | |
9780 | */ | |
9781 | if (has_branch_stack(event)) | |
9782 | return -EOPNOTSUPP; | |
9783 | ||
ba3dd36c PZ |
9784 | perf_swevent_init_hrtimer(event); |
9785 | ||
b0a873eb | 9786 | return 0; |
6fb2915d LZ |
9787 | } |
9788 | ||
b0a873eb | 9789 | static struct pmu perf_task_clock = { |
89a1e187 PZ |
9790 | .task_ctx_nr = perf_sw_context, |
9791 | ||
34f43927 PZ |
9792 | .capabilities = PERF_PMU_CAP_NO_NMI, |
9793 | ||
b0a873eb | 9794 | .event_init = task_clock_event_init, |
a4eaf7f1 PZ |
9795 | .add = task_clock_event_add, |
9796 | .del = task_clock_event_del, | |
9797 | .start = task_clock_event_start, | |
9798 | .stop = task_clock_event_stop, | |
b0a873eb PZ |
9799 | .read = task_clock_event_read, |
9800 | }; | |
6fb2915d | 9801 | |
ad5133b7 | 9802 | static void perf_pmu_nop_void(struct pmu *pmu) |
e077df4f | 9803 | { |
e077df4f | 9804 | } |
6fb2915d | 9805 | |
fbbe0701 SB |
9806 | static void perf_pmu_nop_txn(struct pmu *pmu, unsigned int flags) |
9807 | { | |
9808 | } | |
9809 | ||
ad5133b7 | 9810 | static int perf_pmu_nop_int(struct pmu *pmu) |
6fb2915d | 9811 | { |
ad5133b7 | 9812 | return 0; |
6fb2915d LZ |
9813 | } |
9814 | ||
81ec3f3c JO |
9815 | static int perf_event_nop_int(struct perf_event *event, u64 value) |
9816 | { | |
9817 | return 0; | |
9818 | } | |
9819 | ||
18ab2cd3 | 9820 | static DEFINE_PER_CPU(unsigned int, nop_txn_flags); |
fbbe0701 SB |
9821 | |
9822 | static void perf_pmu_start_txn(struct pmu *pmu, unsigned int flags) | |
6fb2915d | 9823 | { |
fbbe0701 SB |
9824 | __this_cpu_write(nop_txn_flags, flags); |
9825 | ||
9826 | if (flags & ~PERF_PMU_TXN_ADD) | |
9827 | return; | |
9828 | ||
ad5133b7 | 9829 | perf_pmu_disable(pmu); |
6fb2915d LZ |
9830 | } |
9831 | ||
ad5133b7 PZ |
9832 | static int perf_pmu_commit_txn(struct pmu *pmu) |
9833 | { | |
fbbe0701 SB |
9834 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
9835 | ||
9836 | __this_cpu_write(nop_txn_flags, 0); | |
9837 | ||
9838 | if (flags & ~PERF_PMU_TXN_ADD) | |
9839 | return 0; | |
9840 | ||
ad5133b7 PZ |
9841 | perf_pmu_enable(pmu); |
9842 | return 0; | |
9843 | } | |
e077df4f | 9844 | |
ad5133b7 | 9845 | static void perf_pmu_cancel_txn(struct pmu *pmu) |
24f1e32c | 9846 | { |
fbbe0701 SB |
9847 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
9848 | ||
9849 | __this_cpu_write(nop_txn_flags, 0); | |
9850 | ||
9851 | if (flags & ~PERF_PMU_TXN_ADD) | |
9852 | return; | |
9853 | ||
ad5133b7 | 9854 | perf_pmu_enable(pmu); |
24f1e32c FW |
9855 | } |
9856 | ||
35edc2a5 PZ |
9857 | static int perf_event_idx_default(struct perf_event *event) |
9858 | { | |
c719f560 | 9859 | return 0; |
35edc2a5 PZ |
9860 | } |
9861 | ||
8dc85d54 PZ |
9862 | /* |
9863 | * Ensures all contexts with the same task_ctx_nr have the same | |
9864 | * pmu_cpu_context too. | |
9865 | */ | |
9e317041 | 9866 | static struct perf_cpu_context __percpu *find_pmu_context(int ctxn) |
24f1e32c | 9867 | { |
8dc85d54 | 9868 | struct pmu *pmu; |
b326e956 | 9869 | |
8dc85d54 PZ |
9870 | if (ctxn < 0) |
9871 | return NULL; | |
24f1e32c | 9872 | |
8dc85d54 PZ |
9873 | list_for_each_entry(pmu, &pmus, entry) { |
9874 | if (pmu->task_ctx_nr == ctxn) | |
9875 | return pmu->pmu_cpu_context; | |
9876 | } | |
24f1e32c | 9877 | |
8dc85d54 | 9878 | return NULL; |
24f1e32c FW |
9879 | } |
9880 | ||
51676957 PZ |
9881 | static void free_pmu_context(struct pmu *pmu) |
9882 | { | |
df0062b2 WD |
9883 | /* |
9884 | * Static contexts such as perf_sw_context have a global lifetime | |
9885 | * and may be shared between different PMUs. Avoid freeing them | |
9886 | * when a single PMU is going away. | |
9887 | */ | |
9888 | if (pmu->task_ctx_nr > perf_invalid_context) | |
9889 | return; | |
9890 | ||
51676957 | 9891 | free_percpu(pmu->pmu_cpu_context); |
24f1e32c | 9892 | } |
6e855cd4 AS |
9893 | |
9894 | /* | |
9895 | * Let userspace know that this PMU supports address range filtering: | |
9896 | */ | |
9897 | static ssize_t nr_addr_filters_show(struct device *dev, | |
9898 | struct device_attribute *attr, | |
9899 | char *page) | |
9900 | { | |
9901 | struct pmu *pmu = dev_get_drvdata(dev); | |
9902 | ||
9903 | return snprintf(page, PAGE_SIZE - 1, "%d\n", pmu->nr_addr_filters); | |
9904 | } | |
9905 | DEVICE_ATTR_RO(nr_addr_filters); | |
9906 | ||
2e80a82a | 9907 | static struct idr pmu_idr; |
d6d020e9 | 9908 | |
abe43400 PZ |
9909 | static ssize_t |
9910 | type_show(struct device *dev, struct device_attribute *attr, char *page) | |
9911 | { | |
9912 | struct pmu *pmu = dev_get_drvdata(dev); | |
9913 | ||
9914 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->type); | |
9915 | } | |
90826ca7 | 9916 | static DEVICE_ATTR_RO(type); |
abe43400 | 9917 | |
62b85639 SE |
9918 | static ssize_t |
9919 | perf_event_mux_interval_ms_show(struct device *dev, | |
9920 | struct device_attribute *attr, | |
9921 | char *page) | |
9922 | { | |
9923 | struct pmu *pmu = dev_get_drvdata(dev); | |
9924 | ||
9925 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->hrtimer_interval_ms); | |
9926 | } | |
9927 | ||
272325c4 PZ |
9928 | static DEFINE_MUTEX(mux_interval_mutex); |
9929 | ||
62b85639 SE |
9930 | static ssize_t |
9931 | perf_event_mux_interval_ms_store(struct device *dev, | |
9932 | struct device_attribute *attr, | |
9933 | const char *buf, size_t count) | |
9934 | { | |
9935 | struct pmu *pmu = dev_get_drvdata(dev); | |
9936 | int timer, cpu, ret; | |
9937 | ||
9938 | ret = kstrtoint(buf, 0, &timer); | |
9939 | if (ret) | |
9940 | return ret; | |
9941 | ||
9942 | if (timer < 1) | |
9943 | return -EINVAL; | |
9944 | ||
9945 | /* same value, noting to do */ | |
9946 | if (timer == pmu->hrtimer_interval_ms) | |
9947 | return count; | |
9948 | ||
272325c4 | 9949 | mutex_lock(&mux_interval_mutex); |
62b85639 SE |
9950 | pmu->hrtimer_interval_ms = timer; |
9951 | ||
9952 | /* update all cpuctx for this PMU */ | |
a63fbed7 | 9953 | cpus_read_lock(); |
272325c4 | 9954 | for_each_online_cpu(cpu) { |
62b85639 SE |
9955 | struct perf_cpu_context *cpuctx; |
9956 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
9957 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * timer); | |
9958 | ||
272325c4 PZ |
9959 | cpu_function_call(cpu, |
9960 | (remote_function_f)perf_mux_hrtimer_restart, cpuctx); | |
62b85639 | 9961 | } |
a63fbed7 | 9962 | cpus_read_unlock(); |
272325c4 | 9963 | mutex_unlock(&mux_interval_mutex); |
62b85639 SE |
9964 | |
9965 | return count; | |
9966 | } | |
90826ca7 | 9967 | static DEVICE_ATTR_RW(perf_event_mux_interval_ms); |
62b85639 | 9968 | |
90826ca7 GKH |
9969 | static struct attribute *pmu_dev_attrs[] = { |
9970 | &dev_attr_type.attr, | |
9971 | &dev_attr_perf_event_mux_interval_ms.attr, | |
9972 | NULL, | |
abe43400 | 9973 | }; |
90826ca7 | 9974 | ATTRIBUTE_GROUPS(pmu_dev); |
abe43400 PZ |
9975 | |
9976 | static int pmu_bus_running; | |
9977 | static struct bus_type pmu_bus = { | |
9978 | .name = "event_source", | |
90826ca7 | 9979 | .dev_groups = pmu_dev_groups, |
abe43400 PZ |
9980 | }; |
9981 | ||
9982 | static void pmu_dev_release(struct device *dev) | |
9983 | { | |
9984 | kfree(dev); | |
9985 | } | |
9986 | ||
9987 | static int pmu_dev_alloc(struct pmu *pmu) | |
9988 | { | |
9989 | int ret = -ENOMEM; | |
9990 | ||
9991 | pmu->dev = kzalloc(sizeof(struct device), GFP_KERNEL); | |
9992 | if (!pmu->dev) | |
9993 | goto out; | |
9994 | ||
0c9d42ed | 9995 | pmu->dev->groups = pmu->attr_groups; |
abe43400 PZ |
9996 | device_initialize(pmu->dev); |
9997 | ret = dev_set_name(pmu->dev, "%s", pmu->name); | |
9998 | if (ret) | |
9999 | goto free_dev; | |
10000 | ||
10001 | dev_set_drvdata(pmu->dev, pmu); | |
10002 | pmu->dev->bus = &pmu_bus; | |
10003 | pmu->dev->release = pmu_dev_release; | |
10004 | ret = device_add(pmu->dev); | |
10005 | if (ret) | |
10006 | goto free_dev; | |
10007 | ||
6e855cd4 AS |
10008 | /* For PMUs with address filters, throw in an extra attribute: */ |
10009 | if (pmu->nr_addr_filters) | |
10010 | ret = device_create_file(pmu->dev, &dev_attr_nr_addr_filters); | |
10011 | ||
10012 | if (ret) | |
10013 | goto del_dev; | |
10014 | ||
f3a3a825 JO |
10015 | if (pmu->attr_update) |
10016 | ret = sysfs_update_groups(&pmu->dev->kobj, pmu->attr_update); | |
10017 | ||
10018 | if (ret) | |
10019 | goto del_dev; | |
10020 | ||
abe43400 PZ |
10021 | out: |
10022 | return ret; | |
10023 | ||
6e855cd4 AS |
10024 | del_dev: |
10025 | device_del(pmu->dev); | |
10026 | ||
abe43400 PZ |
10027 | free_dev: |
10028 | put_device(pmu->dev); | |
10029 | goto out; | |
10030 | } | |
10031 | ||
547e9fd7 | 10032 | static struct lock_class_key cpuctx_mutex; |
facc4307 | 10033 | static struct lock_class_key cpuctx_lock; |
547e9fd7 | 10034 | |
03d8e80b | 10035 | int perf_pmu_register(struct pmu *pmu, const char *name, int type) |
24f1e32c | 10036 | { |
108b02cf | 10037 | int cpu, ret; |
24f1e32c | 10038 | |
b0a873eb | 10039 | mutex_lock(&pmus_lock); |
33696fc0 PZ |
10040 | ret = -ENOMEM; |
10041 | pmu->pmu_disable_count = alloc_percpu(int); | |
10042 | if (!pmu->pmu_disable_count) | |
10043 | goto unlock; | |
f29ac756 | 10044 | |
2e80a82a PZ |
10045 | pmu->type = -1; |
10046 | if (!name) | |
10047 | goto skip_type; | |
10048 | pmu->name = name; | |
10049 | ||
10050 | if (type < 0) { | |
0e9c3be2 TH |
10051 | type = idr_alloc(&pmu_idr, pmu, PERF_TYPE_MAX, 0, GFP_KERNEL); |
10052 | if (type < 0) { | |
10053 | ret = type; | |
2e80a82a PZ |
10054 | goto free_pdc; |
10055 | } | |
10056 | } | |
10057 | pmu->type = type; | |
10058 | ||
abe43400 PZ |
10059 | if (pmu_bus_running) { |
10060 | ret = pmu_dev_alloc(pmu); | |
10061 | if (ret) | |
10062 | goto free_idr; | |
10063 | } | |
10064 | ||
2e80a82a | 10065 | skip_type: |
26657848 PZ |
10066 | if (pmu->task_ctx_nr == perf_hw_context) { |
10067 | static int hw_context_taken = 0; | |
10068 | ||
5101ef20 MR |
10069 | /* |
10070 | * Other than systems with heterogeneous CPUs, it never makes | |
10071 | * sense for two PMUs to share perf_hw_context. PMUs which are | |
10072 | * uncore must use perf_invalid_context. | |
10073 | */ | |
10074 | if (WARN_ON_ONCE(hw_context_taken && | |
10075 | !(pmu->capabilities & PERF_PMU_CAP_HETEROGENEOUS_CPUS))) | |
26657848 PZ |
10076 | pmu->task_ctx_nr = perf_invalid_context; |
10077 | ||
10078 | hw_context_taken = 1; | |
10079 | } | |
10080 | ||
8dc85d54 PZ |
10081 | pmu->pmu_cpu_context = find_pmu_context(pmu->task_ctx_nr); |
10082 | if (pmu->pmu_cpu_context) | |
10083 | goto got_cpu_context; | |
f29ac756 | 10084 | |
c4814202 | 10085 | ret = -ENOMEM; |
108b02cf PZ |
10086 | pmu->pmu_cpu_context = alloc_percpu(struct perf_cpu_context); |
10087 | if (!pmu->pmu_cpu_context) | |
abe43400 | 10088 | goto free_dev; |
f344011c | 10089 | |
108b02cf PZ |
10090 | for_each_possible_cpu(cpu) { |
10091 | struct perf_cpu_context *cpuctx; | |
10092 | ||
10093 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
eb184479 | 10094 | __perf_event_init_context(&cpuctx->ctx); |
547e9fd7 | 10095 | lockdep_set_class(&cpuctx->ctx.mutex, &cpuctx_mutex); |
facc4307 | 10096 | lockdep_set_class(&cpuctx->ctx.lock, &cpuctx_lock); |
108b02cf | 10097 | cpuctx->ctx.pmu = pmu; |
a63fbed7 | 10098 | cpuctx->online = cpumask_test_cpu(cpu, perf_online_mask); |
9e630205 | 10099 | |
272325c4 | 10100 | __perf_mux_hrtimer_init(cpuctx, cpu); |
108b02cf | 10101 | } |
76e1d904 | 10102 | |
8dc85d54 | 10103 | got_cpu_context: |
ad5133b7 PZ |
10104 | if (!pmu->start_txn) { |
10105 | if (pmu->pmu_enable) { | |
10106 | /* | |
10107 | * If we have pmu_enable/pmu_disable calls, install | |
10108 | * transaction stubs that use that to try and batch | |
10109 | * hardware accesses. | |
10110 | */ | |
10111 | pmu->start_txn = perf_pmu_start_txn; | |
10112 | pmu->commit_txn = perf_pmu_commit_txn; | |
10113 | pmu->cancel_txn = perf_pmu_cancel_txn; | |
10114 | } else { | |
fbbe0701 | 10115 | pmu->start_txn = perf_pmu_nop_txn; |
ad5133b7 PZ |
10116 | pmu->commit_txn = perf_pmu_nop_int; |
10117 | pmu->cancel_txn = perf_pmu_nop_void; | |
f344011c | 10118 | } |
5c92d124 | 10119 | } |
15dbf27c | 10120 | |
ad5133b7 PZ |
10121 | if (!pmu->pmu_enable) { |
10122 | pmu->pmu_enable = perf_pmu_nop_void; | |
10123 | pmu->pmu_disable = perf_pmu_nop_void; | |
10124 | } | |
10125 | ||
81ec3f3c JO |
10126 | if (!pmu->check_period) |
10127 | pmu->check_period = perf_event_nop_int; | |
10128 | ||
35edc2a5 PZ |
10129 | if (!pmu->event_idx) |
10130 | pmu->event_idx = perf_event_idx_default; | |
10131 | ||
b0a873eb | 10132 | list_add_rcu(&pmu->entry, &pmus); |
bed5b25a | 10133 | atomic_set(&pmu->exclusive_cnt, 0); |
33696fc0 PZ |
10134 | ret = 0; |
10135 | unlock: | |
b0a873eb PZ |
10136 | mutex_unlock(&pmus_lock); |
10137 | ||
33696fc0 | 10138 | return ret; |
108b02cf | 10139 | |
abe43400 PZ |
10140 | free_dev: |
10141 | device_del(pmu->dev); | |
10142 | put_device(pmu->dev); | |
10143 | ||
2e80a82a PZ |
10144 | free_idr: |
10145 | if (pmu->type >= PERF_TYPE_MAX) | |
10146 | idr_remove(&pmu_idr, pmu->type); | |
10147 | ||
108b02cf PZ |
10148 | free_pdc: |
10149 | free_percpu(pmu->pmu_disable_count); | |
10150 | goto unlock; | |
f29ac756 | 10151 | } |
c464c76e | 10152 | EXPORT_SYMBOL_GPL(perf_pmu_register); |
f29ac756 | 10153 | |
b0a873eb | 10154 | void perf_pmu_unregister(struct pmu *pmu) |
5c92d124 | 10155 | { |
b0a873eb PZ |
10156 | mutex_lock(&pmus_lock); |
10157 | list_del_rcu(&pmu->entry); | |
5c92d124 | 10158 | |
0475f9ea | 10159 | /* |
cde8e884 PZ |
10160 | * We dereference the pmu list under both SRCU and regular RCU, so |
10161 | * synchronize against both of those. | |
0475f9ea | 10162 | */ |
b0a873eb | 10163 | synchronize_srcu(&pmus_srcu); |
cde8e884 | 10164 | synchronize_rcu(); |
d6d020e9 | 10165 | |
33696fc0 | 10166 | free_percpu(pmu->pmu_disable_count); |
2e80a82a PZ |
10167 | if (pmu->type >= PERF_TYPE_MAX) |
10168 | idr_remove(&pmu_idr, pmu->type); | |
a9f97721 | 10169 | if (pmu_bus_running) { |
0933840a JO |
10170 | if (pmu->nr_addr_filters) |
10171 | device_remove_file(pmu->dev, &dev_attr_nr_addr_filters); | |
10172 | device_del(pmu->dev); | |
10173 | put_device(pmu->dev); | |
10174 | } | |
51676957 | 10175 | free_pmu_context(pmu); |
a9f97721 | 10176 | mutex_unlock(&pmus_lock); |
b0a873eb | 10177 | } |
c464c76e | 10178 | EXPORT_SYMBOL_GPL(perf_pmu_unregister); |
d6d020e9 | 10179 | |
e321d02d KL |
10180 | static inline bool has_extended_regs(struct perf_event *event) |
10181 | { | |
10182 | return (event->attr.sample_regs_user & PERF_REG_EXTENDED_MASK) || | |
10183 | (event->attr.sample_regs_intr & PERF_REG_EXTENDED_MASK); | |
10184 | } | |
10185 | ||
cc34b98b MR |
10186 | static int perf_try_init_event(struct pmu *pmu, struct perf_event *event) |
10187 | { | |
ccd41c86 | 10188 | struct perf_event_context *ctx = NULL; |
cc34b98b MR |
10189 | int ret; |
10190 | ||
10191 | if (!try_module_get(pmu->module)) | |
10192 | return -ENODEV; | |
ccd41c86 | 10193 | |
0c7296ca PZ |
10194 | /* |
10195 | * A number of pmu->event_init() methods iterate the sibling_list to, | |
10196 | * for example, validate if the group fits on the PMU. Therefore, | |
10197 | * if this is a sibling event, acquire the ctx->mutex to protect | |
10198 | * the sibling_list. | |
10199 | */ | |
10200 | if (event->group_leader != event && pmu->task_ctx_nr != perf_sw_context) { | |
8b10c5e2 PZ |
10201 | /* |
10202 | * This ctx->mutex can nest when we're called through | |
10203 | * inheritance. See the perf_event_ctx_lock_nested() comment. | |
10204 | */ | |
10205 | ctx = perf_event_ctx_lock_nested(event->group_leader, | |
10206 | SINGLE_DEPTH_NESTING); | |
ccd41c86 PZ |
10207 | BUG_ON(!ctx); |
10208 | } | |
10209 | ||
cc34b98b MR |
10210 | event->pmu = pmu; |
10211 | ret = pmu->event_init(event); | |
ccd41c86 PZ |
10212 | |
10213 | if (ctx) | |
10214 | perf_event_ctx_unlock(event->group_leader, ctx); | |
10215 | ||
cc6795ae | 10216 | if (!ret) { |
e321d02d KL |
10217 | if (!(pmu->capabilities & PERF_PMU_CAP_EXTENDED_REGS) && |
10218 | has_extended_regs(event)) | |
10219 | ret = -EOPNOTSUPP; | |
10220 | ||
cc6795ae | 10221 | if (pmu->capabilities & PERF_PMU_CAP_NO_EXCLUDE && |
e321d02d | 10222 | event_has_any_exclude_flag(event)) |
cc6795ae | 10223 | ret = -EINVAL; |
e321d02d KL |
10224 | |
10225 | if (ret && event->destroy) | |
10226 | event->destroy(event); | |
cc6795ae AM |
10227 | } |
10228 | ||
cc34b98b MR |
10229 | if (ret) |
10230 | module_put(pmu->module); | |
10231 | ||
10232 | return ret; | |
10233 | } | |
10234 | ||
18ab2cd3 | 10235 | static struct pmu *perf_init_event(struct perf_event *event) |
b0a873eb | 10236 | { |
85c617ab | 10237 | struct pmu *pmu; |
b0a873eb | 10238 | int idx; |
940c5b29 | 10239 | int ret; |
b0a873eb PZ |
10240 | |
10241 | idx = srcu_read_lock(&pmus_srcu); | |
2e80a82a | 10242 | |
40999312 KL |
10243 | /* Try parent's PMU first: */ |
10244 | if (event->parent && event->parent->pmu) { | |
10245 | pmu = event->parent->pmu; | |
10246 | ret = perf_try_init_event(pmu, event); | |
10247 | if (!ret) | |
10248 | goto unlock; | |
10249 | } | |
10250 | ||
2e80a82a PZ |
10251 | rcu_read_lock(); |
10252 | pmu = idr_find(&pmu_idr, event->attr.type); | |
10253 | rcu_read_unlock(); | |
940c5b29 | 10254 | if (pmu) { |
cc34b98b | 10255 | ret = perf_try_init_event(pmu, event); |
940c5b29 LM |
10256 | if (ret) |
10257 | pmu = ERR_PTR(ret); | |
2e80a82a | 10258 | goto unlock; |
940c5b29 | 10259 | } |
2e80a82a | 10260 | |
b0a873eb | 10261 | list_for_each_entry_rcu(pmu, &pmus, entry) { |
cc34b98b | 10262 | ret = perf_try_init_event(pmu, event); |
b0a873eb | 10263 | if (!ret) |
e5f4d339 | 10264 | goto unlock; |
76e1d904 | 10265 | |
b0a873eb PZ |
10266 | if (ret != -ENOENT) { |
10267 | pmu = ERR_PTR(ret); | |
e5f4d339 | 10268 | goto unlock; |
f344011c | 10269 | } |
5c92d124 | 10270 | } |
e5f4d339 PZ |
10271 | pmu = ERR_PTR(-ENOENT); |
10272 | unlock: | |
b0a873eb | 10273 | srcu_read_unlock(&pmus_srcu, idx); |
15dbf27c | 10274 | |
4aeb0b42 | 10275 | return pmu; |
5c92d124 IM |
10276 | } |
10277 | ||
f2fb6bef KL |
10278 | static void attach_sb_event(struct perf_event *event) |
10279 | { | |
10280 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
10281 | ||
10282 | raw_spin_lock(&pel->lock); | |
10283 | list_add_rcu(&event->sb_list, &pel->list); | |
10284 | raw_spin_unlock(&pel->lock); | |
10285 | } | |
10286 | ||
aab5b71e PZ |
10287 | /* |
10288 | * We keep a list of all !task (and therefore per-cpu) events | |
10289 | * that need to receive side-band records. | |
10290 | * | |
10291 | * This avoids having to scan all the various PMU per-cpu contexts | |
10292 | * looking for them. | |
10293 | */ | |
f2fb6bef KL |
10294 | static void account_pmu_sb_event(struct perf_event *event) |
10295 | { | |
a4f144eb | 10296 | if (is_sb_event(event)) |
f2fb6bef KL |
10297 | attach_sb_event(event); |
10298 | } | |
10299 | ||
4beb31f3 FW |
10300 | static void account_event_cpu(struct perf_event *event, int cpu) |
10301 | { | |
10302 | if (event->parent) | |
10303 | return; | |
10304 | ||
4beb31f3 FW |
10305 | if (is_cgroup_event(event)) |
10306 | atomic_inc(&per_cpu(perf_cgroup_events, cpu)); | |
10307 | } | |
10308 | ||
555e0c1e FW |
10309 | /* Freq events need the tick to stay alive (see perf_event_task_tick). */ |
10310 | static void account_freq_event_nohz(void) | |
10311 | { | |
10312 | #ifdef CONFIG_NO_HZ_FULL | |
10313 | /* Lock so we don't race with concurrent unaccount */ | |
10314 | spin_lock(&nr_freq_lock); | |
10315 | if (atomic_inc_return(&nr_freq_events) == 1) | |
10316 | tick_nohz_dep_set(TICK_DEP_BIT_PERF_EVENTS); | |
10317 | spin_unlock(&nr_freq_lock); | |
10318 | #endif | |
10319 | } | |
10320 | ||
10321 | static void account_freq_event(void) | |
10322 | { | |
10323 | if (tick_nohz_full_enabled()) | |
10324 | account_freq_event_nohz(); | |
10325 | else | |
10326 | atomic_inc(&nr_freq_events); | |
10327 | } | |
10328 | ||
10329 | ||
766d6c07 FW |
10330 | static void account_event(struct perf_event *event) |
10331 | { | |
25432ae9 PZ |
10332 | bool inc = false; |
10333 | ||
4beb31f3 FW |
10334 | if (event->parent) |
10335 | return; | |
10336 | ||
766d6c07 | 10337 | if (event->attach_state & PERF_ATTACH_TASK) |
25432ae9 | 10338 | inc = true; |
766d6c07 FW |
10339 | if (event->attr.mmap || event->attr.mmap_data) |
10340 | atomic_inc(&nr_mmap_events); | |
10341 | if (event->attr.comm) | |
10342 | atomic_inc(&nr_comm_events); | |
e4222673 HB |
10343 | if (event->attr.namespaces) |
10344 | atomic_inc(&nr_namespaces_events); | |
766d6c07 FW |
10345 | if (event->attr.task) |
10346 | atomic_inc(&nr_task_events); | |
555e0c1e FW |
10347 | if (event->attr.freq) |
10348 | account_freq_event(); | |
45ac1403 AH |
10349 | if (event->attr.context_switch) { |
10350 | atomic_inc(&nr_switch_events); | |
25432ae9 | 10351 | inc = true; |
45ac1403 | 10352 | } |
4beb31f3 | 10353 | if (has_branch_stack(event)) |
25432ae9 | 10354 | inc = true; |
4beb31f3 | 10355 | if (is_cgroup_event(event)) |
25432ae9 | 10356 | inc = true; |
76193a94 SL |
10357 | if (event->attr.ksymbol) |
10358 | atomic_inc(&nr_ksymbol_events); | |
6ee52e2a SL |
10359 | if (event->attr.bpf_event) |
10360 | atomic_inc(&nr_bpf_events); | |
25432ae9 | 10361 | |
9107c89e | 10362 | if (inc) { |
5bce9db1 AS |
10363 | /* |
10364 | * We need the mutex here because static_branch_enable() | |
10365 | * must complete *before* the perf_sched_count increment | |
10366 | * becomes visible. | |
10367 | */ | |
9107c89e PZ |
10368 | if (atomic_inc_not_zero(&perf_sched_count)) |
10369 | goto enabled; | |
10370 | ||
10371 | mutex_lock(&perf_sched_mutex); | |
10372 | if (!atomic_read(&perf_sched_count)) { | |
10373 | static_branch_enable(&perf_sched_events); | |
10374 | /* | |
10375 | * Guarantee that all CPUs observe they key change and | |
10376 | * call the perf scheduling hooks before proceeding to | |
10377 | * install events that need them. | |
10378 | */ | |
0809d954 | 10379 | synchronize_rcu(); |
9107c89e PZ |
10380 | } |
10381 | /* | |
10382 | * Now that we have waited for the sync_sched(), allow further | |
10383 | * increments to by-pass the mutex. | |
10384 | */ | |
10385 | atomic_inc(&perf_sched_count); | |
10386 | mutex_unlock(&perf_sched_mutex); | |
10387 | } | |
10388 | enabled: | |
4beb31f3 FW |
10389 | |
10390 | account_event_cpu(event, event->cpu); | |
f2fb6bef KL |
10391 | |
10392 | account_pmu_sb_event(event); | |
766d6c07 FW |
10393 | } |
10394 | ||
0793a61d | 10395 | /* |
788faab7 | 10396 | * Allocate and initialize an event structure |
0793a61d | 10397 | */ |
cdd6c482 | 10398 | static struct perf_event * |
c3f00c70 | 10399 | perf_event_alloc(struct perf_event_attr *attr, int cpu, |
d580ff86 PZ |
10400 | struct task_struct *task, |
10401 | struct perf_event *group_leader, | |
10402 | struct perf_event *parent_event, | |
4dc0da86 | 10403 | perf_overflow_handler_t overflow_handler, |
79dff51e | 10404 | void *context, int cgroup_fd) |
0793a61d | 10405 | { |
51b0fe39 | 10406 | struct pmu *pmu; |
cdd6c482 IM |
10407 | struct perf_event *event; |
10408 | struct hw_perf_event *hwc; | |
90983b16 | 10409 | long err = -EINVAL; |
0793a61d | 10410 | |
66832eb4 ON |
10411 | if ((unsigned)cpu >= nr_cpu_ids) { |
10412 | if (!task || cpu != -1) | |
10413 | return ERR_PTR(-EINVAL); | |
10414 | } | |
10415 | ||
c3f00c70 | 10416 | event = kzalloc(sizeof(*event), GFP_KERNEL); |
cdd6c482 | 10417 | if (!event) |
d5d2bc0d | 10418 | return ERR_PTR(-ENOMEM); |
0793a61d | 10419 | |
04289bb9 | 10420 | /* |
cdd6c482 | 10421 | * Single events are their own group leaders, with an |
04289bb9 IM |
10422 | * empty sibling list: |
10423 | */ | |
10424 | if (!group_leader) | |
cdd6c482 | 10425 | group_leader = event; |
04289bb9 | 10426 | |
cdd6c482 IM |
10427 | mutex_init(&event->child_mutex); |
10428 | INIT_LIST_HEAD(&event->child_list); | |
fccc714b | 10429 | |
cdd6c482 IM |
10430 | INIT_LIST_HEAD(&event->event_entry); |
10431 | INIT_LIST_HEAD(&event->sibling_list); | |
6668128a | 10432 | INIT_LIST_HEAD(&event->active_list); |
8e1a2031 | 10433 | init_event_group(event); |
10c6db11 | 10434 | INIT_LIST_HEAD(&event->rb_entry); |
71ad88ef | 10435 | INIT_LIST_HEAD(&event->active_entry); |
375637bc | 10436 | INIT_LIST_HEAD(&event->addr_filters.list); |
f3ae75de SE |
10437 | INIT_HLIST_NODE(&event->hlist_entry); |
10438 | ||
10c6db11 | 10439 | |
cdd6c482 | 10440 | init_waitqueue_head(&event->waitq); |
1d54ad94 | 10441 | event->pending_disable = -1; |
e360adbe | 10442 | init_irq_work(&event->pending, perf_pending_event); |
0793a61d | 10443 | |
cdd6c482 | 10444 | mutex_init(&event->mmap_mutex); |
375637bc | 10445 | raw_spin_lock_init(&event->addr_filters.lock); |
7b732a75 | 10446 | |
a6fa941d | 10447 | atomic_long_set(&event->refcount, 1); |
cdd6c482 IM |
10448 | event->cpu = cpu; |
10449 | event->attr = *attr; | |
10450 | event->group_leader = group_leader; | |
10451 | event->pmu = NULL; | |
cdd6c482 | 10452 | event->oncpu = -1; |
a96bbc16 | 10453 | |
cdd6c482 | 10454 | event->parent = parent_event; |
b84fbc9f | 10455 | |
17cf22c3 | 10456 | event->ns = get_pid_ns(task_active_pid_ns(current)); |
cdd6c482 | 10457 | event->id = atomic64_inc_return(&perf_event_id); |
a96bbc16 | 10458 | |
cdd6c482 | 10459 | event->state = PERF_EVENT_STATE_INACTIVE; |
329d876d | 10460 | |
d580ff86 PZ |
10461 | if (task) { |
10462 | event->attach_state = PERF_ATTACH_TASK; | |
d580ff86 | 10463 | /* |
50f16a8b PZ |
10464 | * XXX pmu::event_init needs to know what task to account to |
10465 | * and we cannot use the ctx information because we need the | |
10466 | * pmu before we get a ctx. | |
d580ff86 | 10467 | */ |
7b3c92b8 | 10468 | event->hw.target = get_task_struct(task); |
d580ff86 PZ |
10469 | } |
10470 | ||
34f43927 PZ |
10471 | event->clock = &local_clock; |
10472 | if (parent_event) | |
10473 | event->clock = parent_event->clock; | |
10474 | ||
4dc0da86 | 10475 | if (!overflow_handler && parent_event) { |
b326e956 | 10476 | overflow_handler = parent_event->overflow_handler; |
4dc0da86 | 10477 | context = parent_event->overflow_handler_context; |
f1e4ba5b | 10478 | #if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_EVENT_TRACING) |
aa6a5f3c AS |
10479 | if (overflow_handler == bpf_overflow_handler) { |
10480 | struct bpf_prog *prog = bpf_prog_inc(parent_event->prog); | |
10481 | ||
10482 | if (IS_ERR(prog)) { | |
10483 | err = PTR_ERR(prog); | |
10484 | goto err_ns; | |
10485 | } | |
10486 | event->prog = prog; | |
10487 | event->orig_overflow_handler = | |
10488 | parent_event->orig_overflow_handler; | |
10489 | } | |
10490 | #endif | |
4dc0da86 | 10491 | } |
66832eb4 | 10492 | |
1879445d WN |
10493 | if (overflow_handler) { |
10494 | event->overflow_handler = overflow_handler; | |
10495 | event->overflow_handler_context = context; | |
9ecda41a WN |
10496 | } else if (is_write_backward(event)){ |
10497 | event->overflow_handler = perf_event_output_backward; | |
10498 | event->overflow_handler_context = NULL; | |
1879445d | 10499 | } else { |
9ecda41a | 10500 | event->overflow_handler = perf_event_output_forward; |
1879445d WN |
10501 | event->overflow_handler_context = NULL; |
10502 | } | |
97eaf530 | 10503 | |
0231bb53 | 10504 | perf_event__state_init(event); |
a86ed508 | 10505 | |
4aeb0b42 | 10506 | pmu = NULL; |
b8e83514 | 10507 | |
cdd6c482 | 10508 | hwc = &event->hw; |
bd2b5b12 | 10509 | hwc->sample_period = attr->sample_period; |
0d48696f | 10510 | if (attr->freq && attr->sample_freq) |
bd2b5b12 | 10511 | hwc->sample_period = 1; |
eced1dfc | 10512 | hwc->last_period = hwc->sample_period; |
bd2b5b12 | 10513 | |
e7850595 | 10514 | local64_set(&hwc->period_left, hwc->sample_period); |
60db5e09 | 10515 | |
2023b359 | 10516 | /* |
ba5213ae PZ |
10517 | * We currently do not support PERF_SAMPLE_READ on inherited events. |
10518 | * See perf_output_read(). | |
2023b359 | 10519 | */ |
ba5213ae | 10520 | if (attr->inherit && (attr->sample_type & PERF_SAMPLE_READ)) |
90983b16 | 10521 | goto err_ns; |
a46a2300 YZ |
10522 | |
10523 | if (!has_branch_stack(event)) | |
10524 | event->attr.branch_sample_type = 0; | |
2023b359 | 10525 | |
79dff51e MF |
10526 | if (cgroup_fd != -1) { |
10527 | err = perf_cgroup_connect(cgroup_fd, event, attr, group_leader); | |
10528 | if (err) | |
10529 | goto err_ns; | |
10530 | } | |
10531 | ||
b0a873eb | 10532 | pmu = perf_init_event(event); |
85c617ab | 10533 | if (IS_ERR(pmu)) { |
4aeb0b42 | 10534 | err = PTR_ERR(pmu); |
90983b16 | 10535 | goto err_ns; |
621a01ea | 10536 | } |
d5d2bc0d | 10537 | |
09f4e8f0 PZ |
10538 | /* |
10539 | * Disallow uncore-cgroup events, they don't make sense as the cgroup will | |
10540 | * be different on other CPUs in the uncore mask. | |
10541 | */ | |
10542 | if (pmu->task_ctx_nr == perf_invalid_context && cgroup_fd != -1) { | |
10543 | err = -EINVAL; | |
10544 | goto err_pmu; | |
10545 | } | |
10546 | ||
ab43762e AS |
10547 | if (event->attr.aux_output && |
10548 | !(pmu->capabilities & PERF_PMU_CAP_AUX_OUTPUT)) { | |
10549 | err = -EOPNOTSUPP; | |
10550 | goto err_pmu; | |
10551 | } | |
10552 | ||
bed5b25a AS |
10553 | err = exclusive_event_init(event); |
10554 | if (err) | |
10555 | goto err_pmu; | |
10556 | ||
375637bc | 10557 | if (has_addr_filter(event)) { |
c60f83b8 AS |
10558 | event->addr_filter_ranges = kcalloc(pmu->nr_addr_filters, |
10559 | sizeof(struct perf_addr_filter_range), | |
10560 | GFP_KERNEL); | |
10561 | if (!event->addr_filter_ranges) { | |
36cc2b92 | 10562 | err = -ENOMEM; |
375637bc | 10563 | goto err_per_task; |
36cc2b92 | 10564 | } |
375637bc | 10565 | |
18736eef AS |
10566 | /* |
10567 | * Clone the parent's vma offsets: they are valid until exec() | |
10568 | * even if the mm is not shared with the parent. | |
10569 | */ | |
10570 | if (event->parent) { | |
10571 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
10572 | ||
10573 | raw_spin_lock_irq(&ifh->lock); | |
c60f83b8 AS |
10574 | memcpy(event->addr_filter_ranges, |
10575 | event->parent->addr_filter_ranges, | |
10576 | pmu->nr_addr_filters * sizeof(struct perf_addr_filter_range)); | |
18736eef AS |
10577 | raw_spin_unlock_irq(&ifh->lock); |
10578 | } | |
10579 | ||
375637bc AS |
10580 | /* force hw sync on the address filters */ |
10581 | event->addr_filters_gen = 1; | |
10582 | } | |
10583 | ||
cdd6c482 | 10584 | if (!event->parent) { |
927c7a9e | 10585 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) { |
97c79a38 | 10586 | err = get_callchain_buffers(attr->sample_max_stack); |
90983b16 | 10587 | if (err) |
375637bc | 10588 | goto err_addr_filters; |
d010b332 | 10589 | } |
f344011c | 10590 | } |
9ee318a7 | 10591 | |
927a5570 AS |
10592 | /* symmetric to unaccount_event() in _free_event() */ |
10593 | account_event(event); | |
10594 | ||
cdd6c482 | 10595 | return event; |
90983b16 | 10596 | |
375637bc | 10597 | err_addr_filters: |
c60f83b8 | 10598 | kfree(event->addr_filter_ranges); |
375637bc | 10599 | |
bed5b25a AS |
10600 | err_per_task: |
10601 | exclusive_event_destroy(event); | |
10602 | ||
90983b16 FW |
10603 | err_pmu: |
10604 | if (event->destroy) | |
10605 | event->destroy(event); | |
c464c76e | 10606 | module_put(pmu->module); |
90983b16 | 10607 | err_ns: |
79dff51e MF |
10608 | if (is_cgroup_event(event)) |
10609 | perf_detach_cgroup(event); | |
90983b16 FW |
10610 | if (event->ns) |
10611 | put_pid_ns(event->ns); | |
621b6d2e PB |
10612 | if (event->hw.target) |
10613 | put_task_struct(event->hw.target); | |
90983b16 FW |
10614 | kfree(event); |
10615 | ||
10616 | return ERR_PTR(err); | |
0793a61d TG |
10617 | } |
10618 | ||
cdd6c482 IM |
10619 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
10620 | struct perf_event_attr *attr) | |
974802ea | 10621 | { |
974802ea | 10622 | u32 size; |
cdf8073d | 10623 | int ret; |
974802ea | 10624 | |
c2ba8f41 | 10625 | /* Zero the full structure, so that a short copy will be nice. */ |
974802ea PZ |
10626 | memset(attr, 0, sizeof(*attr)); |
10627 | ||
10628 | ret = get_user(size, &uattr->size); | |
10629 | if (ret) | |
10630 | return ret; | |
10631 | ||
c2ba8f41 AS |
10632 | /* ABI compatibility quirk: */ |
10633 | if (!size) | |
974802ea | 10634 | size = PERF_ATTR_SIZE_VER0; |
c2ba8f41 | 10635 | if (size < PERF_ATTR_SIZE_VER0 || size > PAGE_SIZE) |
974802ea PZ |
10636 | goto err_size; |
10637 | ||
c2ba8f41 AS |
10638 | ret = copy_struct_from_user(attr, sizeof(*attr), uattr, size); |
10639 | if (ret) { | |
10640 | if (ret == -E2BIG) | |
10641 | goto err_size; | |
10642 | return ret; | |
974802ea PZ |
10643 | } |
10644 | ||
f12f42ac MX |
10645 | attr->size = size; |
10646 | ||
8c7e9756 | 10647 | if (attr->__reserved_1 || attr->__reserved_2) |
974802ea PZ |
10648 | return -EINVAL; |
10649 | ||
10650 | if (attr->sample_type & ~(PERF_SAMPLE_MAX-1)) | |
10651 | return -EINVAL; | |
10652 | ||
10653 | if (attr->read_format & ~(PERF_FORMAT_MAX-1)) | |
10654 | return -EINVAL; | |
10655 | ||
bce38cd5 SE |
10656 | if (attr->sample_type & PERF_SAMPLE_BRANCH_STACK) { |
10657 | u64 mask = attr->branch_sample_type; | |
10658 | ||
10659 | /* only using defined bits */ | |
10660 | if (mask & ~(PERF_SAMPLE_BRANCH_MAX-1)) | |
10661 | return -EINVAL; | |
10662 | ||
10663 | /* at least one branch bit must be set */ | |
10664 | if (!(mask & ~PERF_SAMPLE_BRANCH_PLM_ALL)) | |
10665 | return -EINVAL; | |
10666 | ||
bce38cd5 SE |
10667 | /* propagate priv level, when not set for branch */ |
10668 | if (!(mask & PERF_SAMPLE_BRANCH_PLM_ALL)) { | |
10669 | ||
10670 | /* exclude_kernel checked on syscall entry */ | |
10671 | if (!attr->exclude_kernel) | |
10672 | mask |= PERF_SAMPLE_BRANCH_KERNEL; | |
10673 | ||
10674 | if (!attr->exclude_user) | |
10675 | mask |= PERF_SAMPLE_BRANCH_USER; | |
10676 | ||
10677 | if (!attr->exclude_hv) | |
10678 | mask |= PERF_SAMPLE_BRANCH_HV; | |
10679 | /* | |
10680 | * adjust user setting (for HW filter setup) | |
10681 | */ | |
10682 | attr->branch_sample_type = mask; | |
10683 | } | |
e712209a SE |
10684 | /* privileged levels capture (kernel, hv): check permissions */ |
10685 | if ((mask & PERF_SAMPLE_BRANCH_PERM_PLM) | |
2b923c8f SE |
10686 | && perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) |
10687 | return -EACCES; | |
bce38cd5 | 10688 | } |
4018994f | 10689 | |
c5ebcedb | 10690 | if (attr->sample_type & PERF_SAMPLE_REGS_USER) { |
4018994f | 10691 | ret = perf_reg_validate(attr->sample_regs_user); |
c5ebcedb JO |
10692 | if (ret) |
10693 | return ret; | |
10694 | } | |
10695 | ||
10696 | if (attr->sample_type & PERF_SAMPLE_STACK_USER) { | |
10697 | if (!arch_perf_have_user_stack_dump()) | |
10698 | return -ENOSYS; | |
10699 | ||
10700 | /* | |
10701 | * We have __u32 type for the size, but so far | |
10702 | * we can only use __u16 as maximum due to the | |
10703 | * __u16 sample size limit. | |
10704 | */ | |
10705 | if (attr->sample_stack_user >= USHRT_MAX) | |
78b562fb | 10706 | return -EINVAL; |
c5ebcedb | 10707 | else if (!IS_ALIGNED(attr->sample_stack_user, sizeof(u64))) |
78b562fb | 10708 | return -EINVAL; |
c5ebcedb | 10709 | } |
4018994f | 10710 | |
5f970521 JO |
10711 | if (!attr->sample_max_stack) |
10712 | attr->sample_max_stack = sysctl_perf_event_max_stack; | |
10713 | ||
60e2364e SE |
10714 | if (attr->sample_type & PERF_SAMPLE_REGS_INTR) |
10715 | ret = perf_reg_validate(attr->sample_regs_intr); | |
974802ea PZ |
10716 | out: |
10717 | return ret; | |
10718 | ||
10719 | err_size: | |
10720 | put_user(sizeof(*attr), &uattr->size); | |
10721 | ret = -E2BIG; | |
10722 | goto out; | |
10723 | } | |
10724 | ||
ac9721f3 PZ |
10725 | static int |
10726 | perf_event_set_output(struct perf_event *event, struct perf_event *output_event) | |
a4be7c27 | 10727 | { |
b69cf536 | 10728 | struct ring_buffer *rb = NULL; |
a4be7c27 PZ |
10729 | int ret = -EINVAL; |
10730 | ||
ac9721f3 | 10731 | if (!output_event) |
a4be7c27 PZ |
10732 | goto set; |
10733 | ||
ac9721f3 PZ |
10734 | /* don't allow circular references */ |
10735 | if (event == output_event) | |
a4be7c27 PZ |
10736 | goto out; |
10737 | ||
0f139300 PZ |
10738 | /* |
10739 | * Don't allow cross-cpu buffers | |
10740 | */ | |
10741 | if (output_event->cpu != event->cpu) | |
10742 | goto out; | |
10743 | ||
10744 | /* | |
76369139 | 10745 | * If its not a per-cpu rb, it must be the same task. |
0f139300 PZ |
10746 | */ |
10747 | if (output_event->cpu == -1 && output_event->ctx != event->ctx) | |
10748 | goto out; | |
10749 | ||
34f43927 PZ |
10750 | /* |
10751 | * Mixing clocks in the same buffer is trouble you don't need. | |
10752 | */ | |
10753 | if (output_event->clock != event->clock) | |
10754 | goto out; | |
10755 | ||
9ecda41a WN |
10756 | /* |
10757 | * Either writing ring buffer from beginning or from end. | |
10758 | * Mixing is not allowed. | |
10759 | */ | |
10760 | if (is_write_backward(output_event) != is_write_backward(event)) | |
10761 | goto out; | |
10762 | ||
45bfb2e5 PZ |
10763 | /* |
10764 | * If both events generate aux data, they must be on the same PMU | |
10765 | */ | |
10766 | if (has_aux(event) && has_aux(output_event) && | |
10767 | event->pmu != output_event->pmu) | |
10768 | goto out; | |
10769 | ||
a4be7c27 | 10770 | set: |
cdd6c482 | 10771 | mutex_lock(&event->mmap_mutex); |
ac9721f3 PZ |
10772 | /* Can't redirect output if we've got an active mmap() */ |
10773 | if (atomic_read(&event->mmap_count)) | |
10774 | goto unlock; | |
a4be7c27 | 10775 | |
ac9721f3 | 10776 | if (output_event) { |
76369139 FW |
10777 | /* get the rb we want to redirect to */ |
10778 | rb = ring_buffer_get(output_event); | |
10779 | if (!rb) | |
ac9721f3 | 10780 | goto unlock; |
a4be7c27 PZ |
10781 | } |
10782 | ||
b69cf536 | 10783 | ring_buffer_attach(event, rb); |
9bb5d40c | 10784 | |
a4be7c27 | 10785 | ret = 0; |
ac9721f3 PZ |
10786 | unlock: |
10787 | mutex_unlock(&event->mmap_mutex); | |
10788 | ||
a4be7c27 | 10789 | out: |
a4be7c27 PZ |
10790 | return ret; |
10791 | } | |
10792 | ||
f63a8daa PZ |
10793 | static void mutex_lock_double(struct mutex *a, struct mutex *b) |
10794 | { | |
10795 | if (b < a) | |
10796 | swap(a, b); | |
10797 | ||
10798 | mutex_lock(a); | |
10799 | mutex_lock_nested(b, SINGLE_DEPTH_NESTING); | |
10800 | } | |
10801 | ||
34f43927 PZ |
10802 | static int perf_event_set_clock(struct perf_event *event, clockid_t clk_id) |
10803 | { | |
10804 | bool nmi_safe = false; | |
10805 | ||
10806 | switch (clk_id) { | |
10807 | case CLOCK_MONOTONIC: | |
10808 | event->clock = &ktime_get_mono_fast_ns; | |
10809 | nmi_safe = true; | |
10810 | break; | |
10811 | ||
10812 | case CLOCK_MONOTONIC_RAW: | |
10813 | event->clock = &ktime_get_raw_fast_ns; | |
10814 | nmi_safe = true; | |
10815 | break; | |
10816 | ||
10817 | case CLOCK_REALTIME: | |
10818 | event->clock = &ktime_get_real_ns; | |
10819 | break; | |
10820 | ||
10821 | case CLOCK_BOOTTIME: | |
9285ec4c | 10822 | event->clock = &ktime_get_boottime_ns; |
34f43927 PZ |
10823 | break; |
10824 | ||
10825 | case CLOCK_TAI: | |
9285ec4c | 10826 | event->clock = &ktime_get_clocktai_ns; |
34f43927 PZ |
10827 | break; |
10828 | ||
10829 | default: | |
10830 | return -EINVAL; | |
10831 | } | |
10832 | ||
10833 | if (!nmi_safe && !(event->pmu->capabilities & PERF_PMU_CAP_NO_NMI)) | |
10834 | return -EINVAL; | |
10835 | ||
10836 | return 0; | |
10837 | } | |
10838 | ||
321027c1 PZ |
10839 | /* |
10840 | * Variation on perf_event_ctx_lock_nested(), except we take two context | |
10841 | * mutexes. | |
10842 | */ | |
10843 | static struct perf_event_context * | |
10844 | __perf_event_ctx_lock_double(struct perf_event *group_leader, | |
10845 | struct perf_event_context *ctx) | |
10846 | { | |
10847 | struct perf_event_context *gctx; | |
10848 | ||
10849 | again: | |
10850 | rcu_read_lock(); | |
10851 | gctx = READ_ONCE(group_leader->ctx); | |
8c94abbb | 10852 | if (!refcount_inc_not_zero(&gctx->refcount)) { |
321027c1 PZ |
10853 | rcu_read_unlock(); |
10854 | goto again; | |
10855 | } | |
10856 | rcu_read_unlock(); | |
10857 | ||
10858 | mutex_lock_double(&gctx->mutex, &ctx->mutex); | |
10859 | ||
10860 | if (group_leader->ctx != gctx) { | |
10861 | mutex_unlock(&ctx->mutex); | |
10862 | mutex_unlock(&gctx->mutex); | |
10863 | put_ctx(gctx); | |
10864 | goto again; | |
10865 | } | |
10866 | ||
10867 | return gctx; | |
10868 | } | |
10869 | ||
0793a61d | 10870 | /** |
cdd6c482 | 10871 | * sys_perf_event_open - open a performance event, associate it to a task/cpu |
9f66a381 | 10872 | * |
cdd6c482 | 10873 | * @attr_uptr: event_id type attributes for monitoring/sampling |
0793a61d | 10874 | * @pid: target pid |
9f66a381 | 10875 | * @cpu: target cpu |
cdd6c482 | 10876 | * @group_fd: group leader event fd |
0793a61d | 10877 | */ |
cdd6c482 IM |
10878 | SYSCALL_DEFINE5(perf_event_open, |
10879 | struct perf_event_attr __user *, attr_uptr, | |
2743a5b0 | 10880 | pid_t, pid, int, cpu, int, group_fd, unsigned long, flags) |
0793a61d | 10881 | { |
b04243ef PZ |
10882 | struct perf_event *group_leader = NULL, *output_event = NULL; |
10883 | struct perf_event *event, *sibling; | |
cdd6c482 | 10884 | struct perf_event_attr attr; |
f63a8daa | 10885 | struct perf_event_context *ctx, *uninitialized_var(gctx); |
cdd6c482 | 10886 | struct file *event_file = NULL; |
2903ff01 | 10887 | struct fd group = {NULL, 0}; |
38a81da2 | 10888 | struct task_struct *task = NULL; |
89a1e187 | 10889 | struct pmu *pmu; |
ea635c64 | 10890 | int event_fd; |
b04243ef | 10891 | int move_group = 0; |
dc86cabe | 10892 | int err; |
a21b0b35 | 10893 | int f_flags = O_RDWR; |
79dff51e | 10894 | int cgroup_fd = -1; |
0793a61d | 10895 | |
2743a5b0 | 10896 | /* for future expandability... */ |
e5d1367f | 10897 | if (flags & ~PERF_FLAG_ALL) |
2743a5b0 PM |
10898 | return -EINVAL; |
10899 | ||
dc86cabe IM |
10900 | err = perf_copy_attr(attr_uptr, &attr); |
10901 | if (err) | |
10902 | return err; | |
eab656ae | 10903 | |
0764771d PZ |
10904 | if (!attr.exclude_kernel) { |
10905 | if (perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) | |
10906 | return -EACCES; | |
10907 | } | |
10908 | ||
e4222673 HB |
10909 | if (attr.namespaces) { |
10910 | if (!capable(CAP_SYS_ADMIN)) | |
10911 | return -EACCES; | |
10912 | } | |
10913 | ||
df58ab24 | 10914 | if (attr.freq) { |
cdd6c482 | 10915 | if (attr.sample_freq > sysctl_perf_event_sample_rate) |
df58ab24 | 10916 | return -EINVAL; |
0819b2e3 PZ |
10917 | } else { |
10918 | if (attr.sample_period & (1ULL << 63)) | |
10919 | return -EINVAL; | |
df58ab24 PZ |
10920 | } |
10921 | ||
fc7ce9c7 KL |
10922 | /* Only privileged users can get physical addresses */ |
10923 | if ((attr.sample_type & PERF_SAMPLE_PHYS_ADDR) && | |
10924 | perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) | |
10925 | return -EACCES; | |
10926 | ||
b0c8fdc7 DH |
10927 | err = security_locked_down(LOCKDOWN_PERF); |
10928 | if (err && (attr.sample_type & PERF_SAMPLE_REGS_INTR)) | |
10929 | /* REGS_INTR can leak data, lockdown must prevent this */ | |
10930 | return err; | |
10931 | ||
10932 | err = 0; | |
10933 | ||
e5d1367f SE |
10934 | /* |
10935 | * In cgroup mode, the pid argument is used to pass the fd | |
10936 | * opened to the cgroup directory in cgroupfs. The cpu argument | |
10937 | * designates the cpu on which to monitor threads from that | |
10938 | * cgroup. | |
10939 | */ | |
10940 | if ((flags & PERF_FLAG_PID_CGROUP) && (pid == -1 || cpu == -1)) | |
10941 | return -EINVAL; | |
10942 | ||
a21b0b35 YD |
10943 | if (flags & PERF_FLAG_FD_CLOEXEC) |
10944 | f_flags |= O_CLOEXEC; | |
10945 | ||
10946 | event_fd = get_unused_fd_flags(f_flags); | |
ea635c64 AV |
10947 | if (event_fd < 0) |
10948 | return event_fd; | |
10949 | ||
ac9721f3 | 10950 | if (group_fd != -1) { |
2903ff01 AV |
10951 | err = perf_fget_light(group_fd, &group); |
10952 | if (err) | |
d14b12d7 | 10953 | goto err_fd; |
2903ff01 | 10954 | group_leader = group.file->private_data; |
ac9721f3 PZ |
10955 | if (flags & PERF_FLAG_FD_OUTPUT) |
10956 | output_event = group_leader; | |
10957 | if (flags & PERF_FLAG_FD_NO_GROUP) | |
10958 | group_leader = NULL; | |
10959 | } | |
10960 | ||
e5d1367f | 10961 | if (pid != -1 && !(flags & PERF_FLAG_PID_CGROUP)) { |
c6be5a5c PZ |
10962 | task = find_lively_task_by_vpid(pid); |
10963 | if (IS_ERR(task)) { | |
10964 | err = PTR_ERR(task); | |
10965 | goto err_group_fd; | |
10966 | } | |
10967 | } | |
10968 | ||
1f4ee503 PZ |
10969 | if (task && group_leader && |
10970 | group_leader->attr.inherit != attr.inherit) { | |
10971 | err = -EINVAL; | |
10972 | goto err_task; | |
10973 | } | |
10974 | ||
79c9ce57 PZ |
10975 | if (task) { |
10976 | err = mutex_lock_interruptible(&task->signal->cred_guard_mutex); | |
10977 | if (err) | |
e5aeee51 | 10978 | goto err_task; |
79c9ce57 PZ |
10979 | |
10980 | /* | |
10981 | * Reuse ptrace permission checks for now. | |
10982 | * | |
10983 | * We must hold cred_guard_mutex across this and any potential | |
10984 | * perf_install_in_context() call for this new event to | |
10985 | * serialize against exec() altering our credentials (and the | |
10986 | * perf_event_exit_task() that could imply). | |
10987 | */ | |
10988 | err = -EACCES; | |
10989 | if (!ptrace_may_access(task, PTRACE_MODE_READ_REALCREDS)) | |
10990 | goto err_cred; | |
10991 | } | |
10992 | ||
79dff51e MF |
10993 | if (flags & PERF_FLAG_PID_CGROUP) |
10994 | cgroup_fd = pid; | |
10995 | ||
4dc0da86 | 10996 | event = perf_event_alloc(&attr, cpu, task, group_leader, NULL, |
79dff51e | 10997 | NULL, NULL, cgroup_fd); |
d14b12d7 SE |
10998 | if (IS_ERR(event)) { |
10999 | err = PTR_ERR(event); | |
79c9ce57 | 11000 | goto err_cred; |
d14b12d7 SE |
11001 | } |
11002 | ||
53b25335 VW |
11003 | if (is_sampling_event(event)) { |
11004 | if (event->pmu->capabilities & PERF_PMU_CAP_NO_INTERRUPT) { | |
a1396555 | 11005 | err = -EOPNOTSUPP; |
53b25335 VW |
11006 | goto err_alloc; |
11007 | } | |
11008 | } | |
11009 | ||
89a1e187 PZ |
11010 | /* |
11011 | * Special case software events and allow them to be part of | |
11012 | * any hardware group. | |
11013 | */ | |
11014 | pmu = event->pmu; | |
b04243ef | 11015 | |
34f43927 PZ |
11016 | if (attr.use_clockid) { |
11017 | err = perf_event_set_clock(event, attr.clockid); | |
11018 | if (err) | |
11019 | goto err_alloc; | |
11020 | } | |
11021 | ||
4ff6a8de DCC |
11022 | if (pmu->task_ctx_nr == perf_sw_context) |
11023 | event->event_caps |= PERF_EV_CAP_SOFTWARE; | |
11024 | ||
a1150c20 SL |
11025 | if (group_leader) { |
11026 | if (is_software_event(event) && | |
11027 | !in_software_context(group_leader)) { | |
b04243ef | 11028 | /* |
a1150c20 SL |
11029 | * If the event is a sw event, but the group_leader |
11030 | * is on hw context. | |
b04243ef | 11031 | * |
a1150c20 SL |
11032 | * Allow the addition of software events to hw |
11033 | * groups, this is safe because software events | |
11034 | * never fail to schedule. | |
b04243ef | 11035 | */ |
a1150c20 SL |
11036 | pmu = group_leader->ctx->pmu; |
11037 | } else if (!is_software_event(event) && | |
11038 | is_software_event(group_leader) && | |
4ff6a8de | 11039 | (group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { |
b04243ef PZ |
11040 | /* |
11041 | * In case the group is a pure software group, and we | |
11042 | * try to add a hardware event, move the whole group to | |
11043 | * the hardware context. | |
11044 | */ | |
11045 | move_group = 1; | |
11046 | } | |
11047 | } | |
89a1e187 PZ |
11048 | |
11049 | /* | |
11050 | * Get the target context (task or percpu): | |
11051 | */ | |
4af57ef2 | 11052 | ctx = find_get_context(pmu, task, event); |
89a1e187 PZ |
11053 | if (IS_ERR(ctx)) { |
11054 | err = PTR_ERR(ctx); | |
c6be5a5c | 11055 | goto err_alloc; |
89a1e187 PZ |
11056 | } |
11057 | ||
ccff286d | 11058 | /* |
cdd6c482 | 11059 | * Look up the group leader (we will attach this event to it): |
04289bb9 | 11060 | */ |
ac9721f3 | 11061 | if (group_leader) { |
dc86cabe | 11062 | err = -EINVAL; |
04289bb9 | 11063 | |
04289bb9 | 11064 | /* |
ccff286d IM |
11065 | * Do not allow a recursive hierarchy (this new sibling |
11066 | * becoming part of another group-sibling): | |
11067 | */ | |
11068 | if (group_leader->group_leader != group_leader) | |
c3f00c70 | 11069 | goto err_context; |
34f43927 PZ |
11070 | |
11071 | /* All events in a group should have the same clock */ | |
11072 | if (group_leader->clock != event->clock) | |
11073 | goto err_context; | |
11074 | ||
ccff286d | 11075 | /* |
64aee2a9 MR |
11076 | * Make sure we're both events for the same CPU; |
11077 | * grouping events for different CPUs is broken; since | |
11078 | * you can never concurrently schedule them anyhow. | |
04289bb9 | 11079 | */ |
64aee2a9 MR |
11080 | if (group_leader->cpu != event->cpu) |
11081 | goto err_context; | |
c3c87e77 | 11082 | |
64aee2a9 MR |
11083 | /* |
11084 | * Make sure we're both on the same task, or both | |
11085 | * per-CPU events. | |
11086 | */ | |
11087 | if (group_leader->ctx->task != ctx->task) | |
11088 | goto err_context; | |
11089 | ||
11090 | /* | |
11091 | * Do not allow to attach to a group in a different task | |
11092 | * or CPU context. If we're moving SW events, we'll fix | |
11093 | * this up later, so allow that. | |
11094 | */ | |
11095 | if (!move_group && group_leader->ctx != ctx) | |
11096 | goto err_context; | |
b04243ef | 11097 | |
3b6f9e5c PM |
11098 | /* |
11099 | * Only a group leader can be exclusive or pinned | |
11100 | */ | |
0d48696f | 11101 | if (attr.exclusive || attr.pinned) |
c3f00c70 | 11102 | goto err_context; |
ac9721f3 PZ |
11103 | } |
11104 | ||
11105 | if (output_event) { | |
11106 | err = perf_event_set_output(event, output_event); | |
11107 | if (err) | |
c3f00c70 | 11108 | goto err_context; |
ac9721f3 | 11109 | } |
0793a61d | 11110 | |
a21b0b35 YD |
11111 | event_file = anon_inode_getfile("[perf_event]", &perf_fops, event, |
11112 | f_flags); | |
ea635c64 AV |
11113 | if (IS_ERR(event_file)) { |
11114 | err = PTR_ERR(event_file); | |
201c2f85 | 11115 | event_file = NULL; |
c3f00c70 | 11116 | goto err_context; |
ea635c64 | 11117 | } |
9b51f66d | 11118 | |
b04243ef | 11119 | if (move_group) { |
321027c1 PZ |
11120 | gctx = __perf_event_ctx_lock_double(group_leader, ctx); |
11121 | ||
84c4e620 PZ |
11122 | if (gctx->task == TASK_TOMBSTONE) { |
11123 | err = -ESRCH; | |
11124 | goto err_locked; | |
11125 | } | |
321027c1 PZ |
11126 | |
11127 | /* | |
11128 | * Check if we raced against another sys_perf_event_open() call | |
11129 | * moving the software group underneath us. | |
11130 | */ | |
11131 | if (!(group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { | |
11132 | /* | |
11133 | * If someone moved the group out from under us, check | |
11134 | * if this new event wound up on the same ctx, if so | |
11135 | * its the regular !move_group case, otherwise fail. | |
11136 | */ | |
11137 | if (gctx != ctx) { | |
11138 | err = -EINVAL; | |
11139 | goto err_locked; | |
11140 | } else { | |
11141 | perf_event_ctx_unlock(group_leader, gctx); | |
11142 | move_group = 0; | |
11143 | } | |
11144 | } | |
8a58ddae AS |
11145 | |
11146 | /* | |
11147 | * Failure to create exclusive events returns -EBUSY. | |
11148 | */ | |
11149 | err = -EBUSY; | |
11150 | if (!exclusive_event_installable(group_leader, ctx)) | |
11151 | goto err_locked; | |
11152 | ||
11153 | for_each_sibling_event(sibling, group_leader) { | |
11154 | if (!exclusive_event_installable(sibling, ctx)) | |
11155 | goto err_locked; | |
11156 | } | |
f55fc2a5 PZ |
11157 | } else { |
11158 | mutex_lock(&ctx->mutex); | |
11159 | } | |
11160 | ||
84c4e620 PZ |
11161 | if (ctx->task == TASK_TOMBSTONE) { |
11162 | err = -ESRCH; | |
11163 | goto err_locked; | |
11164 | } | |
11165 | ||
a723968c PZ |
11166 | if (!perf_event_validate_size(event)) { |
11167 | err = -E2BIG; | |
11168 | goto err_locked; | |
11169 | } | |
11170 | ||
a63fbed7 TG |
11171 | if (!task) { |
11172 | /* | |
11173 | * Check if the @cpu we're creating an event for is online. | |
11174 | * | |
11175 | * We use the perf_cpu_context::ctx::mutex to serialize against | |
11176 | * the hotplug notifiers. See perf_event_{init,exit}_cpu(). | |
11177 | */ | |
11178 | struct perf_cpu_context *cpuctx = | |
11179 | container_of(ctx, struct perf_cpu_context, ctx); | |
11180 | ||
11181 | if (!cpuctx->online) { | |
11182 | err = -ENODEV; | |
11183 | goto err_locked; | |
11184 | } | |
11185 | } | |
11186 | ||
ab43762e AS |
11187 | if (event->attr.aux_output && !perf_get_aux_event(event, group_leader)) |
11188 | goto err_locked; | |
a63fbed7 | 11189 | |
f55fc2a5 PZ |
11190 | /* |
11191 | * Must be under the same ctx::mutex as perf_install_in_context(), | |
11192 | * because we need to serialize with concurrent event creation. | |
11193 | */ | |
11194 | if (!exclusive_event_installable(event, ctx)) { | |
f55fc2a5 PZ |
11195 | err = -EBUSY; |
11196 | goto err_locked; | |
11197 | } | |
f63a8daa | 11198 | |
f55fc2a5 PZ |
11199 | WARN_ON_ONCE(ctx->parent_ctx); |
11200 | ||
79c9ce57 PZ |
11201 | /* |
11202 | * This is the point on no return; we cannot fail hereafter. This is | |
11203 | * where we start modifying current state. | |
11204 | */ | |
11205 | ||
f55fc2a5 | 11206 | if (move_group) { |
f63a8daa PZ |
11207 | /* |
11208 | * See perf_event_ctx_lock() for comments on the details | |
11209 | * of swizzling perf_event::ctx. | |
11210 | */ | |
45a0e07a | 11211 | perf_remove_from_context(group_leader, 0); |
279b5165 | 11212 | put_ctx(gctx); |
0231bb53 | 11213 | |
edb39592 | 11214 | for_each_sibling_event(sibling, group_leader) { |
45a0e07a | 11215 | perf_remove_from_context(sibling, 0); |
b04243ef PZ |
11216 | put_ctx(gctx); |
11217 | } | |
b04243ef | 11218 | |
f63a8daa PZ |
11219 | /* |
11220 | * Wait for everybody to stop referencing the events through | |
11221 | * the old lists, before installing it on new lists. | |
11222 | */ | |
0cda4c02 | 11223 | synchronize_rcu(); |
f63a8daa | 11224 | |
8f95b435 PZI |
11225 | /* |
11226 | * Install the group siblings before the group leader. | |
11227 | * | |
11228 | * Because a group leader will try and install the entire group | |
11229 | * (through the sibling list, which is still in-tact), we can | |
11230 | * end up with siblings installed in the wrong context. | |
11231 | * | |
11232 | * By installing siblings first we NO-OP because they're not | |
11233 | * reachable through the group lists. | |
11234 | */ | |
edb39592 | 11235 | for_each_sibling_event(sibling, group_leader) { |
8f95b435 | 11236 | perf_event__state_init(sibling); |
9fc81d87 | 11237 | perf_install_in_context(ctx, sibling, sibling->cpu); |
b04243ef PZ |
11238 | get_ctx(ctx); |
11239 | } | |
8f95b435 PZI |
11240 | |
11241 | /* | |
11242 | * Removing from the context ends up with disabled | |
11243 | * event. What we want here is event in the initial | |
11244 | * startup state, ready to be add into new context. | |
11245 | */ | |
11246 | perf_event__state_init(group_leader); | |
11247 | perf_install_in_context(ctx, group_leader, group_leader->cpu); | |
11248 | get_ctx(ctx); | |
bed5b25a AS |
11249 | } |
11250 | ||
f73e22ab PZ |
11251 | /* |
11252 | * Precalculate sample_data sizes; do while holding ctx::mutex such | |
11253 | * that we're serialized against further additions and before | |
11254 | * perf_install_in_context() which is the point the event is active and | |
11255 | * can use these values. | |
11256 | */ | |
11257 | perf_event__header_size(event); | |
11258 | perf_event__id_header_size(event); | |
11259 | ||
78cd2c74 PZ |
11260 | event->owner = current; |
11261 | ||
e2d37cd2 | 11262 | perf_install_in_context(ctx, event, event->cpu); |
fe4b04fa | 11263 | perf_unpin_context(ctx); |
f63a8daa | 11264 | |
f55fc2a5 | 11265 | if (move_group) |
321027c1 | 11266 | perf_event_ctx_unlock(group_leader, gctx); |
d859e29f | 11267 | mutex_unlock(&ctx->mutex); |
9b51f66d | 11268 | |
79c9ce57 PZ |
11269 | if (task) { |
11270 | mutex_unlock(&task->signal->cred_guard_mutex); | |
11271 | put_task_struct(task); | |
11272 | } | |
11273 | ||
cdd6c482 IM |
11274 | mutex_lock(¤t->perf_event_mutex); |
11275 | list_add_tail(&event->owner_entry, ¤t->perf_event_list); | |
11276 | mutex_unlock(¤t->perf_event_mutex); | |
082ff5a2 | 11277 | |
8a49542c PZ |
11278 | /* |
11279 | * Drop the reference on the group_event after placing the | |
11280 | * new event on the sibling_list. This ensures destruction | |
11281 | * of the group leader will find the pointer to itself in | |
11282 | * perf_group_detach(). | |
11283 | */ | |
2903ff01 | 11284 | fdput(group); |
ea635c64 AV |
11285 | fd_install(event_fd, event_file); |
11286 | return event_fd; | |
0793a61d | 11287 | |
f55fc2a5 PZ |
11288 | err_locked: |
11289 | if (move_group) | |
321027c1 | 11290 | perf_event_ctx_unlock(group_leader, gctx); |
f55fc2a5 PZ |
11291 | mutex_unlock(&ctx->mutex); |
11292 | /* err_file: */ | |
11293 | fput(event_file); | |
c3f00c70 | 11294 | err_context: |
fe4b04fa | 11295 | perf_unpin_context(ctx); |
ea635c64 | 11296 | put_ctx(ctx); |
c6be5a5c | 11297 | err_alloc: |
13005627 PZ |
11298 | /* |
11299 | * If event_file is set, the fput() above will have called ->release() | |
11300 | * and that will take care of freeing the event. | |
11301 | */ | |
11302 | if (!event_file) | |
11303 | free_event(event); | |
79c9ce57 PZ |
11304 | err_cred: |
11305 | if (task) | |
11306 | mutex_unlock(&task->signal->cred_guard_mutex); | |
1f4ee503 | 11307 | err_task: |
e7d0bc04 PZ |
11308 | if (task) |
11309 | put_task_struct(task); | |
89a1e187 | 11310 | err_group_fd: |
2903ff01 | 11311 | fdput(group); |
ea635c64 AV |
11312 | err_fd: |
11313 | put_unused_fd(event_fd); | |
dc86cabe | 11314 | return err; |
0793a61d TG |
11315 | } |
11316 | ||
fb0459d7 AV |
11317 | /** |
11318 | * perf_event_create_kernel_counter | |
11319 | * | |
11320 | * @attr: attributes of the counter to create | |
11321 | * @cpu: cpu in which the counter is bound | |
38a81da2 | 11322 | * @task: task to profile (NULL for percpu) |
fb0459d7 AV |
11323 | */ |
11324 | struct perf_event * | |
11325 | perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, | |
38a81da2 | 11326 | struct task_struct *task, |
4dc0da86 AK |
11327 | perf_overflow_handler_t overflow_handler, |
11328 | void *context) | |
fb0459d7 | 11329 | { |
fb0459d7 | 11330 | struct perf_event_context *ctx; |
c3f00c70 | 11331 | struct perf_event *event; |
fb0459d7 | 11332 | int err; |
d859e29f | 11333 | |
dce5affb AS |
11334 | /* |
11335 | * Grouping is not supported for kernel events, neither is 'AUX', | |
11336 | * make sure the caller's intentions are adjusted. | |
11337 | */ | |
11338 | if (attr->aux_output) | |
11339 | return ERR_PTR(-EINVAL); | |
11340 | ||
4dc0da86 | 11341 | event = perf_event_alloc(attr, cpu, task, NULL, NULL, |
79dff51e | 11342 | overflow_handler, context, -1); |
c3f00c70 PZ |
11343 | if (IS_ERR(event)) { |
11344 | err = PTR_ERR(event); | |
11345 | goto err; | |
11346 | } | |
d859e29f | 11347 | |
f8697762 | 11348 | /* Mark owner so we could distinguish it from user events. */ |
63b6da39 | 11349 | event->owner = TASK_TOMBSTONE; |
f8697762 | 11350 | |
f25d8ba9 AS |
11351 | /* |
11352 | * Get the target context (task or percpu): | |
11353 | */ | |
4af57ef2 | 11354 | ctx = find_get_context(event->pmu, task, event); |
c6567f64 FW |
11355 | if (IS_ERR(ctx)) { |
11356 | err = PTR_ERR(ctx); | |
c3f00c70 | 11357 | goto err_free; |
d859e29f | 11358 | } |
fb0459d7 | 11359 | |
fb0459d7 AV |
11360 | WARN_ON_ONCE(ctx->parent_ctx); |
11361 | mutex_lock(&ctx->mutex); | |
84c4e620 PZ |
11362 | if (ctx->task == TASK_TOMBSTONE) { |
11363 | err = -ESRCH; | |
11364 | goto err_unlock; | |
11365 | } | |
11366 | ||
a63fbed7 TG |
11367 | if (!task) { |
11368 | /* | |
11369 | * Check if the @cpu we're creating an event for is online. | |
11370 | * | |
11371 | * We use the perf_cpu_context::ctx::mutex to serialize against | |
11372 | * the hotplug notifiers. See perf_event_{init,exit}_cpu(). | |
11373 | */ | |
11374 | struct perf_cpu_context *cpuctx = | |
11375 | container_of(ctx, struct perf_cpu_context, ctx); | |
11376 | if (!cpuctx->online) { | |
11377 | err = -ENODEV; | |
11378 | goto err_unlock; | |
11379 | } | |
11380 | } | |
11381 | ||
bed5b25a | 11382 | if (!exclusive_event_installable(event, ctx)) { |
bed5b25a | 11383 | err = -EBUSY; |
84c4e620 | 11384 | goto err_unlock; |
bed5b25a AS |
11385 | } |
11386 | ||
4ce54af8 | 11387 | perf_install_in_context(ctx, event, event->cpu); |
fe4b04fa | 11388 | perf_unpin_context(ctx); |
fb0459d7 AV |
11389 | mutex_unlock(&ctx->mutex); |
11390 | ||
fb0459d7 AV |
11391 | return event; |
11392 | ||
84c4e620 PZ |
11393 | err_unlock: |
11394 | mutex_unlock(&ctx->mutex); | |
11395 | perf_unpin_context(ctx); | |
11396 | put_ctx(ctx); | |
c3f00c70 PZ |
11397 | err_free: |
11398 | free_event(event); | |
11399 | err: | |
c6567f64 | 11400 | return ERR_PTR(err); |
9b51f66d | 11401 | } |
fb0459d7 | 11402 | EXPORT_SYMBOL_GPL(perf_event_create_kernel_counter); |
9b51f66d | 11403 | |
0cda4c02 YZ |
11404 | void perf_pmu_migrate_context(struct pmu *pmu, int src_cpu, int dst_cpu) |
11405 | { | |
11406 | struct perf_event_context *src_ctx; | |
11407 | struct perf_event_context *dst_ctx; | |
11408 | struct perf_event *event, *tmp; | |
11409 | LIST_HEAD(events); | |
11410 | ||
11411 | src_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, src_cpu)->ctx; | |
11412 | dst_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, dst_cpu)->ctx; | |
11413 | ||
f63a8daa PZ |
11414 | /* |
11415 | * See perf_event_ctx_lock() for comments on the details | |
11416 | * of swizzling perf_event::ctx. | |
11417 | */ | |
11418 | mutex_lock_double(&src_ctx->mutex, &dst_ctx->mutex); | |
0cda4c02 YZ |
11419 | list_for_each_entry_safe(event, tmp, &src_ctx->event_list, |
11420 | event_entry) { | |
45a0e07a | 11421 | perf_remove_from_context(event, 0); |
9a545de0 | 11422 | unaccount_event_cpu(event, src_cpu); |
0cda4c02 | 11423 | put_ctx(src_ctx); |
9886167d | 11424 | list_add(&event->migrate_entry, &events); |
0cda4c02 | 11425 | } |
0cda4c02 | 11426 | |
8f95b435 PZI |
11427 | /* |
11428 | * Wait for the events to quiesce before re-instating them. | |
11429 | */ | |
0cda4c02 YZ |
11430 | synchronize_rcu(); |
11431 | ||
8f95b435 PZI |
11432 | /* |
11433 | * Re-instate events in 2 passes. | |
11434 | * | |
11435 | * Skip over group leaders and only install siblings on this first | |
11436 | * pass, siblings will not get enabled without a leader, however a | |
11437 | * leader will enable its siblings, even if those are still on the old | |
11438 | * context. | |
11439 | */ | |
11440 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { | |
11441 | if (event->group_leader == event) | |
11442 | continue; | |
11443 | ||
11444 | list_del(&event->migrate_entry); | |
11445 | if (event->state >= PERF_EVENT_STATE_OFF) | |
11446 | event->state = PERF_EVENT_STATE_INACTIVE; | |
11447 | account_event_cpu(event, dst_cpu); | |
11448 | perf_install_in_context(dst_ctx, event, dst_cpu); | |
11449 | get_ctx(dst_ctx); | |
11450 | } | |
11451 | ||
11452 | /* | |
11453 | * Once all the siblings are setup properly, install the group leaders | |
11454 | * to make it go. | |
11455 | */ | |
9886167d PZ |
11456 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { |
11457 | list_del(&event->migrate_entry); | |
0cda4c02 YZ |
11458 | if (event->state >= PERF_EVENT_STATE_OFF) |
11459 | event->state = PERF_EVENT_STATE_INACTIVE; | |
9a545de0 | 11460 | account_event_cpu(event, dst_cpu); |
0cda4c02 YZ |
11461 | perf_install_in_context(dst_ctx, event, dst_cpu); |
11462 | get_ctx(dst_ctx); | |
11463 | } | |
11464 | mutex_unlock(&dst_ctx->mutex); | |
f63a8daa | 11465 | mutex_unlock(&src_ctx->mutex); |
0cda4c02 YZ |
11466 | } |
11467 | EXPORT_SYMBOL_GPL(perf_pmu_migrate_context); | |
11468 | ||
cdd6c482 | 11469 | static void sync_child_event(struct perf_event *child_event, |
38b200d6 | 11470 | struct task_struct *child) |
d859e29f | 11471 | { |
cdd6c482 | 11472 | struct perf_event *parent_event = child_event->parent; |
8bc20959 | 11473 | u64 child_val; |
d859e29f | 11474 | |
cdd6c482 IM |
11475 | if (child_event->attr.inherit_stat) |
11476 | perf_event_read_event(child_event, child); | |
38b200d6 | 11477 | |
b5e58793 | 11478 | child_val = perf_event_count(child_event); |
d859e29f PM |
11479 | |
11480 | /* | |
11481 | * Add back the child's count to the parent's count: | |
11482 | */ | |
a6e6dea6 | 11483 | atomic64_add(child_val, &parent_event->child_count); |
cdd6c482 IM |
11484 | atomic64_add(child_event->total_time_enabled, |
11485 | &parent_event->child_total_time_enabled); | |
11486 | atomic64_add(child_event->total_time_running, | |
11487 | &parent_event->child_total_time_running); | |
d859e29f PM |
11488 | } |
11489 | ||
9b51f66d | 11490 | static void |
8ba289b8 PZ |
11491 | perf_event_exit_event(struct perf_event *child_event, |
11492 | struct perf_event_context *child_ctx, | |
11493 | struct task_struct *child) | |
9b51f66d | 11494 | { |
8ba289b8 PZ |
11495 | struct perf_event *parent_event = child_event->parent; |
11496 | ||
1903d50c PZ |
11497 | /* |
11498 | * Do not destroy the 'original' grouping; because of the context | |
11499 | * switch optimization the original events could've ended up in a | |
11500 | * random child task. | |
11501 | * | |
11502 | * If we were to destroy the original group, all group related | |
11503 | * operations would cease to function properly after this random | |
11504 | * child dies. | |
11505 | * | |
11506 | * Do destroy all inherited groups, we don't care about those | |
11507 | * and being thorough is better. | |
11508 | */ | |
32132a3d PZ |
11509 | raw_spin_lock_irq(&child_ctx->lock); |
11510 | WARN_ON_ONCE(child_ctx->is_active); | |
11511 | ||
8ba289b8 | 11512 | if (parent_event) |
32132a3d PZ |
11513 | perf_group_detach(child_event); |
11514 | list_del_event(child_event, child_ctx); | |
0d3d73aa | 11515 | perf_event_set_state(child_event, PERF_EVENT_STATE_EXIT); /* is_event_hup() */ |
32132a3d | 11516 | raw_spin_unlock_irq(&child_ctx->lock); |
0cc0c027 | 11517 | |
9b51f66d | 11518 | /* |
8ba289b8 | 11519 | * Parent events are governed by their filedesc, retain them. |
9b51f66d | 11520 | */ |
8ba289b8 | 11521 | if (!parent_event) { |
179033b3 | 11522 | perf_event_wakeup(child_event); |
8ba289b8 | 11523 | return; |
4bcf349a | 11524 | } |
8ba289b8 PZ |
11525 | /* |
11526 | * Child events can be cleaned up. | |
11527 | */ | |
11528 | ||
11529 | sync_child_event(child_event, child); | |
11530 | ||
11531 | /* | |
11532 | * Remove this event from the parent's list | |
11533 | */ | |
11534 | WARN_ON_ONCE(parent_event->ctx->parent_ctx); | |
11535 | mutex_lock(&parent_event->child_mutex); | |
11536 | list_del_init(&child_event->child_list); | |
11537 | mutex_unlock(&parent_event->child_mutex); | |
11538 | ||
11539 | /* | |
11540 | * Kick perf_poll() for is_event_hup(). | |
11541 | */ | |
11542 | perf_event_wakeup(parent_event); | |
11543 | free_event(child_event); | |
11544 | put_event(parent_event); | |
9b51f66d IM |
11545 | } |
11546 | ||
8dc85d54 | 11547 | static void perf_event_exit_task_context(struct task_struct *child, int ctxn) |
9b51f66d | 11548 | { |
211de6eb | 11549 | struct perf_event_context *child_ctx, *clone_ctx = NULL; |
63b6da39 | 11550 | struct perf_event *child_event, *next; |
63b6da39 PZ |
11551 | |
11552 | WARN_ON_ONCE(child != current); | |
9b51f66d | 11553 | |
6a3351b6 | 11554 | child_ctx = perf_pin_task_context(child, ctxn); |
63b6da39 | 11555 | if (!child_ctx) |
9b51f66d IM |
11556 | return; |
11557 | ||
ad3a37de | 11558 | /* |
6a3351b6 PZ |
11559 | * In order to reduce the amount of tricky in ctx tear-down, we hold |
11560 | * ctx::mutex over the entire thing. This serializes against almost | |
11561 | * everything that wants to access the ctx. | |
11562 | * | |
11563 | * The exception is sys_perf_event_open() / | |
11564 | * perf_event_create_kernel_count() which does find_get_context() | |
11565 | * without ctx::mutex (it cannot because of the move_group double mutex | |
11566 | * lock thing). See the comments in perf_install_in_context(). | |
ad3a37de | 11567 | */ |
6a3351b6 | 11568 | mutex_lock(&child_ctx->mutex); |
c93f7669 PM |
11569 | |
11570 | /* | |
6a3351b6 PZ |
11571 | * In a single ctx::lock section, de-schedule the events and detach the |
11572 | * context from the task such that we cannot ever get it scheduled back | |
11573 | * in. | |
c93f7669 | 11574 | */ |
6a3351b6 | 11575 | raw_spin_lock_irq(&child_ctx->lock); |
487f05e1 | 11576 | task_ctx_sched_out(__get_cpu_context(child_ctx), child_ctx, EVENT_ALL); |
4a1c0f26 | 11577 | |
71a851b4 | 11578 | /* |
63b6da39 PZ |
11579 | * Now that the context is inactive, destroy the task <-> ctx relation |
11580 | * and mark the context dead. | |
71a851b4 | 11581 | */ |
63b6da39 PZ |
11582 | RCU_INIT_POINTER(child->perf_event_ctxp[ctxn], NULL); |
11583 | put_ctx(child_ctx); /* cannot be last */ | |
11584 | WRITE_ONCE(child_ctx->task, TASK_TOMBSTONE); | |
11585 | put_task_struct(current); /* cannot be last */ | |
4a1c0f26 | 11586 | |
211de6eb | 11587 | clone_ctx = unclone_ctx(child_ctx); |
6a3351b6 | 11588 | raw_spin_unlock_irq(&child_ctx->lock); |
9f498cc5 | 11589 | |
211de6eb PZ |
11590 | if (clone_ctx) |
11591 | put_ctx(clone_ctx); | |
4a1c0f26 | 11592 | |
9f498cc5 | 11593 | /* |
cdd6c482 IM |
11594 | * Report the task dead after unscheduling the events so that we |
11595 | * won't get any samples after PERF_RECORD_EXIT. We can however still | |
11596 | * get a few PERF_RECORD_READ events. | |
9f498cc5 | 11597 | */ |
cdd6c482 | 11598 | perf_event_task(child, child_ctx, 0); |
a63eaf34 | 11599 | |
ebf905fc | 11600 | list_for_each_entry_safe(child_event, next, &child_ctx->event_list, event_entry) |
8ba289b8 | 11601 | perf_event_exit_event(child_event, child_ctx, child); |
8bc20959 | 11602 | |
a63eaf34 PM |
11603 | mutex_unlock(&child_ctx->mutex); |
11604 | ||
11605 | put_ctx(child_ctx); | |
9b51f66d IM |
11606 | } |
11607 | ||
8dc85d54 PZ |
11608 | /* |
11609 | * When a child task exits, feed back event values to parent events. | |
79c9ce57 PZ |
11610 | * |
11611 | * Can be called with cred_guard_mutex held when called from | |
11612 | * install_exec_creds(). | |
8dc85d54 PZ |
11613 | */ |
11614 | void perf_event_exit_task(struct task_struct *child) | |
11615 | { | |
8882135b | 11616 | struct perf_event *event, *tmp; |
8dc85d54 PZ |
11617 | int ctxn; |
11618 | ||
8882135b PZ |
11619 | mutex_lock(&child->perf_event_mutex); |
11620 | list_for_each_entry_safe(event, tmp, &child->perf_event_list, | |
11621 | owner_entry) { | |
11622 | list_del_init(&event->owner_entry); | |
11623 | ||
11624 | /* | |
11625 | * Ensure the list deletion is visible before we clear | |
11626 | * the owner, closes a race against perf_release() where | |
11627 | * we need to serialize on the owner->perf_event_mutex. | |
11628 | */ | |
f47c02c0 | 11629 | smp_store_release(&event->owner, NULL); |
8882135b PZ |
11630 | } |
11631 | mutex_unlock(&child->perf_event_mutex); | |
11632 | ||
8dc85d54 PZ |
11633 | for_each_task_context_nr(ctxn) |
11634 | perf_event_exit_task_context(child, ctxn); | |
4e93ad60 JO |
11635 | |
11636 | /* | |
11637 | * The perf_event_exit_task_context calls perf_event_task | |
11638 | * with child's task_ctx, which generates EXIT events for | |
11639 | * child contexts and sets child->perf_event_ctxp[] to NULL. | |
11640 | * At this point we need to send EXIT events to cpu contexts. | |
11641 | */ | |
11642 | perf_event_task(child, NULL, 0); | |
8dc85d54 PZ |
11643 | } |
11644 | ||
889ff015 FW |
11645 | static void perf_free_event(struct perf_event *event, |
11646 | struct perf_event_context *ctx) | |
11647 | { | |
11648 | struct perf_event *parent = event->parent; | |
11649 | ||
11650 | if (WARN_ON_ONCE(!parent)) | |
11651 | return; | |
11652 | ||
11653 | mutex_lock(&parent->child_mutex); | |
11654 | list_del_init(&event->child_list); | |
11655 | mutex_unlock(&parent->child_mutex); | |
11656 | ||
a6fa941d | 11657 | put_event(parent); |
889ff015 | 11658 | |
652884fe | 11659 | raw_spin_lock_irq(&ctx->lock); |
8a49542c | 11660 | perf_group_detach(event); |
889ff015 | 11661 | list_del_event(event, ctx); |
652884fe | 11662 | raw_spin_unlock_irq(&ctx->lock); |
889ff015 FW |
11663 | free_event(event); |
11664 | } | |
11665 | ||
bbbee908 | 11666 | /* |
1cf8dfe8 PZ |
11667 | * Free a context as created by inheritance by perf_event_init_task() below, |
11668 | * used by fork() in case of fail. | |
652884fe | 11669 | * |
1cf8dfe8 PZ |
11670 | * Even though the task has never lived, the context and events have been |
11671 | * exposed through the child_list, so we must take care tearing it all down. | |
bbbee908 | 11672 | */ |
cdd6c482 | 11673 | void perf_event_free_task(struct task_struct *task) |
bbbee908 | 11674 | { |
8dc85d54 | 11675 | struct perf_event_context *ctx; |
cdd6c482 | 11676 | struct perf_event *event, *tmp; |
8dc85d54 | 11677 | int ctxn; |
bbbee908 | 11678 | |
8dc85d54 PZ |
11679 | for_each_task_context_nr(ctxn) { |
11680 | ctx = task->perf_event_ctxp[ctxn]; | |
11681 | if (!ctx) | |
11682 | continue; | |
bbbee908 | 11683 | |
8dc85d54 | 11684 | mutex_lock(&ctx->mutex); |
e552a838 PZ |
11685 | raw_spin_lock_irq(&ctx->lock); |
11686 | /* | |
11687 | * Destroy the task <-> ctx relation and mark the context dead. | |
11688 | * | |
11689 | * This is important because even though the task hasn't been | |
11690 | * exposed yet the context has been (through child_list). | |
11691 | */ | |
11692 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], NULL); | |
11693 | WRITE_ONCE(ctx->task, TASK_TOMBSTONE); | |
11694 | put_task_struct(task); /* cannot be last */ | |
11695 | raw_spin_unlock_irq(&ctx->lock); | |
bbbee908 | 11696 | |
15121c78 | 11697 | list_for_each_entry_safe(event, tmp, &ctx->event_list, event_entry) |
8dc85d54 | 11698 | perf_free_event(event, ctx); |
bbbee908 | 11699 | |
8dc85d54 | 11700 | mutex_unlock(&ctx->mutex); |
1cf8dfe8 PZ |
11701 | |
11702 | /* | |
11703 | * perf_event_release_kernel() could've stolen some of our | |
11704 | * child events and still have them on its free_list. In that | |
11705 | * case we must wait for these events to have been freed (in | |
11706 | * particular all their references to this task must've been | |
11707 | * dropped). | |
11708 | * | |
11709 | * Without this copy_process() will unconditionally free this | |
11710 | * task (irrespective of its reference count) and | |
11711 | * _free_event()'s put_task_struct(event->hw.target) will be a | |
11712 | * use-after-free. | |
11713 | * | |
11714 | * Wait for all events to drop their context reference. | |
11715 | */ | |
11716 | wait_var_event(&ctx->refcount, refcount_read(&ctx->refcount) == 1); | |
11717 | put_ctx(ctx); /* must be last */ | |
8dc85d54 | 11718 | } |
889ff015 FW |
11719 | } |
11720 | ||
4e231c79 PZ |
11721 | void perf_event_delayed_put(struct task_struct *task) |
11722 | { | |
11723 | int ctxn; | |
11724 | ||
11725 | for_each_task_context_nr(ctxn) | |
11726 | WARN_ON_ONCE(task->perf_event_ctxp[ctxn]); | |
11727 | } | |
11728 | ||
e03e7ee3 | 11729 | struct file *perf_event_get(unsigned int fd) |
ffe8690c | 11730 | { |
02e5ad97 | 11731 | struct file *file = fget(fd); |
e03e7ee3 AS |
11732 | if (!file) |
11733 | return ERR_PTR(-EBADF); | |
ffe8690c | 11734 | |
e03e7ee3 AS |
11735 | if (file->f_op != &perf_fops) { |
11736 | fput(file); | |
11737 | return ERR_PTR(-EBADF); | |
11738 | } | |
ffe8690c | 11739 | |
e03e7ee3 | 11740 | return file; |
ffe8690c KX |
11741 | } |
11742 | ||
f8d959a5 YS |
11743 | const struct perf_event *perf_get_event(struct file *file) |
11744 | { | |
11745 | if (file->f_op != &perf_fops) | |
11746 | return ERR_PTR(-EINVAL); | |
11747 | ||
11748 | return file->private_data; | |
11749 | } | |
11750 | ||
ffe8690c KX |
11751 | const struct perf_event_attr *perf_event_attrs(struct perf_event *event) |
11752 | { | |
11753 | if (!event) | |
11754 | return ERR_PTR(-EINVAL); | |
11755 | ||
11756 | return &event->attr; | |
11757 | } | |
11758 | ||
97dee4f3 | 11759 | /* |
788faab7 | 11760 | * Inherit an event from parent task to child task. |
d8a8cfc7 PZ |
11761 | * |
11762 | * Returns: | |
11763 | * - valid pointer on success | |
11764 | * - NULL for orphaned events | |
11765 | * - IS_ERR() on error | |
97dee4f3 PZ |
11766 | */ |
11767 | static struct perf_event * | |
11768 | inherit_event(struct perf_event *parent_event, | |
11769 | struct task_struct *parent, | |
11770 | struct perf_event_context *parent_ctx, | |
11771 | struct task_struct *child, | |
11772 | struct perf_event *group_leader, | |
11773 | struct perf_event_context *child_ctx) | |
11774 | { | |
8ca2bd41 | 11775 | enum perf_event_state parent_state = parent_event->state; |
97dee4f3 | 11776 | struct perf_event *child_event; |
cee010ec | 11777 | unsigned long flags; |
97dee4f3 PZ |
11778 | |
11779 | /* | |
11780 | * Instead of creating recursive hierarchies of events, | |
11781 | * we link inherited events back to the original parent, | |
11782 | * which has a filp for sure, which we use as the reference | |
11783 | * count: | |
11784 | */ | |
11785 | if (parent_event->parent) | |
11786 | parent_event = parent_event->parent; | |
11787 | ||
11788 | child_event = perf_event_alloc(&parent_event->attr, | |
11789 | parent_event->cpu, | |
d580ff86 | 11790 | child, |
97dee4f3 | 11791 | group_leader, parent_event, |
79dff51e | 11792 | NULL, NULL, -1); |
97dee4f3 PZ |
11793 | if (IS_ERR(child_event)) |
11794 | return child_event; | |
a6fa941d | 11795 | |
313ccb96 JO |
11796 | |
11797 | if ((child_event->attach_state & PERF_ATTACH_TASK_DATA) && | |
11798 | !child_ctx->task_ctx_data) { | |
11799 | struct pmu *pmu = child_event->pmu; | |
11800 | ||
11801 | child_ctx->task_ctx_data = kzalloc(pmu->task_ctx_size, | |
11802 | GFP_KERNEL); | |
11803 | if (!child_ctx->task_ctx_data) { | |
11804 | free_event(child_event); | |
697d8778 | 11805 | return ERR_PTR(-ENOMEM); |
313ccb96 JO |
11806 | } |
11807 | } | |
11808 | ||
c6e5b732 PZ |
11809 | /* |
11810 | * is_orphaned_event() and list_add_tail(&parent_event->child_list) | |
11811 | * must be under the same lock in order to serialize against | |
11812 | * perf_event_release_kernel(), such that either we must observe | |
11813 | * is_orphaned_event() or they will observe us on the child_list. | |
11814 | */ | |
11815 | mutex_lock(&parent_event->child_mutex); | |
fadfe7be JO |
11816 | if (is_orphaned_event(parent_event) || |
11817 | !atomic_long_inc_not_zero(&parent_event->refcount)) { | |
c6e5b732 | 11818 | mutex_unlock(&parent_event->child_mutex); |
313ccb96 | 11819 | /* task_ctx_data is freed with child_ctx */ |
a6fa941d AV |
11820 | free_event(child_event); |
11821 | return NULL; | |
11822 | } | |
11823 | ||
97dee4f3 PZ |
11824 | get_ctx(child_ctx); |
11825 | ||
11826 | /* | |
11827 | * Make the child state follow the state of the parent event, | |
11828 | * not its attr.disabled bit. We hold the parent's mutex, | |
11829 | * so we won't race with perf_event_{en, dis}able_family. | |
11830 | */ | |
1929def9 | 11831 | if (parent_state >= PERF_EVENT_STATE_INACTIVE) |
97dee4f3 PZ |
11832 | child_event->state = PERF_EVENT_STATE_INACTIVE; |
11833 | else | |
11834 | child_event->state = PERF_EVENT_STATE_OFF; | |
11835 | ||
11836 | if (parent_event->attr.freq) { | |
11837 | u64 sample_period = parent_event->hw.sample_period; | |
11838 | struct hw_perf_event *hwc = &child_event->hw; | |
11839 | ||
11840 | hwc->sample_period = sample_period; | |
11841 | hwc->last_period = sample_period; | |
11842 | ||
11843 | local64_set(&hwc->period_left, sample_period); | |
11844 | } | |
11845 | ||
11846 | child_event->ctx = child_ctx; | |
11847 | child_event->overflow_handler = parent_event->overflow_handler; | |
4dc0da86 AK |
11848 | child_event->overflow_handler_context |
11849 | = parent_event->overflow_handler_context; | |
97dee4f3 | 11850 | |
614b6780 TG |
11851 | /* |
11852 | * Precalculate sample_data sizes | |
11853 | */ | |
11854 | perf_event__header_size(child_event); | |
6844c09d | 11855 | perf_event__id_header_size(child_event); |
614b6780 | 11856 | |
97dee4f3 PZ |
11857 | /* |
11858 | * Link it up in the child's context: | |
11859 | */ | |
cee010ec | 11860 | raw_spin_lock_irqsave(&child_ctx->lock, flags); |
97dee4f3 | 11861 | add_event_to_ctx(child_event, child_ctx); |
cee010ec | 11862 | raw_spin_unlock_irqrestore(&child_ctx->lock, flags); |
97dee4f3 | 11863 | |
97dee4f3 PZ |
11864 | /* |
11865 | * Link this into the parent event's child list | |
11866 | */ | |
97dee4f3 PZ |
11867 | list_add_tail(&child_event->child_list, &parent_event->child_list); |
11868 | mutex_unlock(&parent_event->child_mutex); | |
11869 | ||
11870 | return child_event; | |
11871 | } | |
11872 | ||
d8a8cfc7 PZ |
11873 | /* |
11874 | * Inherits an event group. | |
11875 | * | |
11876 | * This will quietly suppress orphaned events; !inherit_event() is not an error. | |
11877 | * This matches with perf_event_release_kernel() removing all child events. | |
11878 | * | |
11879 | * Returns: | |
11880 | * - 0 on success | |
11881 | * - <0 on error | |
11882 | */ | |
97dee4f3 PZ |
11883 | static int inherit_group(struct perf_event *parent_event, |
11884 | struct task_struct *parent, | |
11885 | struct perf_event_context *parent_ctx, | |
11886 | struct task_struct *child, | |
11887 | struct perf_event_context *child_ctx) | |
11888 | { | |
11889 | struct perf_event *leader; | |
11890 | struct perf_event *sub; | |
11891 | struct perf_event *child_ctr; | |
11892 | ||
11893 | leader = inherit_event(parent_event, parent, parent_ctx, | |
11894 | child, NULL, child_ctx); | |
11895 | if (IS_ERR(leader)) | |
11896 | return PTR_ERR(leader); | |
d8a8cfc7 PZ |
11897 | /* |
11898 | * @leader can be NULL here because of is_orphaned_event(). In this | |
11899 | * case inherit_event() will create individual events, similar to what | |
11900 | * perf_group_detach() would do anyway. | |
11901 | */ | |
edb39592 | 11902 | for_each_sibling_event(sub, parent_event) { |
97dee4f3 PZ |
11903 | child_ctr = inherit_event(sub, parent, parent_ctx, |
11904 | child, leader, child_ctx); | |
11905 | if (IS_ERR(child_ctr)) | |
11906 | return PTR_ERR(child_ctr); | |
f733c6b5 | 11907 | |
00496fe5 | 11908 | if (sub->aux_event == parent_event && child_ctr && |
f733c6b5 AS |
11909 | !perf_get_aux_event(child_ctr, leader)) |
11910 | return -EINVAL; | |
97dee4f3 PZ |
11911 | } |
11912 | return 0; | |
889ff015 FW |
11913 | } |
11914 | ||
d8a8cfc7 PZ |
11915 | /* |
11916 | * Creates the child task context and tries to inherit the event-group. | |
11917 | * | |
11918 | * Clears @inherited_all on !attr.inherited or error. Note that we'll leave | |
11919 | * inherited_all set when we 'fail' to inherit an orphaned event; this is | |
11920 | * consistent with perf_event_release_kernel() removing all child events. | |
11921 | * | |
11922 | * Returns: | |
11923 | * - 0 on success | |
11924 | * - <0 on error | |
11925 | */ | |
889ff015 FW |
11926 | static int |
11927 | inherit_task_group(struct perf_event *event, struct task_struct *parent, | |
11928 | struct perf_event_context *parent_ctx, | |
8dc85d54 | 11929 | struct task_struct *child, int ctxn, |
889ff015 FW |
11930 | int *inherited_all) |
11931 | { | |
11932 | int ret; | |
8dc85d54 | 11933 | struct perf_event_context *child_ctx; |
889ff015 FW |
11934 | |
11935 | if (!event->attr.inherit) { | |
11936 | *inherited_all = 0; | |
11937 | return 0; | |
bbbee908 PZ |
11938 | } |
11939 | ||
fe4b04fa | 11940 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 FW |
11941 | if (!child_ctx) { |
11942 | /* | |
11943 | * This is executed from the parent task context, so | |
11944 | * inherit events that have been marked for cloning. | |
11945 | * First allocate and initialize a context for the | |
11946 | * child. | |
11947 | */ | |
734df5ab | 11948 | child_ctx = alloc_perf_context(parent_ctx->pmu, child); |
889ff015 FW |
11949 | if (!child_ctx) |
11950 | return -ENOMEM; | |
bbbee908 | 11951 | |
8dc85d54 | 11952 | child->perf_event_ctxp[ctxn] = child_ctx; |
889ff015 FW |
11953 | } |
11954 | ||
11955 | ret = inherit_group(event, parent, parent_ctx, | |
11956 | child, child_ctx); | |
11957 | ||
11958 | if (ret) | |
11959 | *inherited_all = 0; | |
11960 | ||
11961 | return ret; | |
bbbee908 PZ |
11962 | } |
11963 | ||
9b51f66d | 11964 | /* |
cdd6c482 | 11965 | * Initialize the perf_event context in task_struct |
9b51f66d | 11966 | */ |
985c8dcb | 11967 | static int perf_event_init_context(struct task_struct *child, int ctxn) |
9b51f66d | 11968 | { |
889ff015 | 11969 | struct perf_event_context *child_ctx, *parent_ctx; |
cdd6c482 IM |
11970 | struct perf_event_context *cloned_ctx; |
11971 | struct perf_event *event; | |
9b51f66d | 11972 | struct task_struct *parent = current; |
564c2b21 | 11973 | int inherited_all = 1; |
dddd3379 | 11974 | unsigned long flags; |
6ab423e0 | 11975 | int ret = 0; |
9b51f66d | 11976 | |
8dc85d54 | 11977 | if (likely(!parent->perf_event_ctxp[ctxn])) |
6ab423e0 PZ |
11978 | return 0; |
11979 | ||
ad3a37de | 11980 | /* |
25346b93 PM |
11981 | * If the parent's context is a clone, pin it so it won't get |
11982 | * swapped under us. | |
ad3a37de | 11983 | */ |
8dc85d54 | 11984 | parent_ctx = perf_pin_task_context(parent, ctxn); |
ffb4ef21 PZ |
11985 | if (!parent_ctx) |
11986 | return 0; | |
25346b93 | 11987 | |
ad3a37de PM |
11988 | /* |
11989 | * No need to check if parent_ctx != NULL here; since we saw | |
11990 | * it non-NULL earlier, the only reason for it to become NULL | |
11991 | * is if we exit, and since we're currently in the middle of | |
11992 | * a fork we can't be exiting at the same time. | |
11993 | */ | |
ad3a37de | 11994 | |
9b51f66d IM |
11995 | /* |
11996 | * Lock the parent list. No need to lock the child - not PID | |
11997 | * hashed yet and not running, so nobody can access it. | |
11998 | */ | |
d859e29f | 11999 | mutex_lock(&parent_ctx->mutex); |
9b51f66d IM |
12000 | |
12001 | /* | |
12002 | * We dont have to disable NMIs - we are only looking at | |
12003 | * the list, not manipulating it: | |
12004 | */ | |
6e6804d2 | 12005 | perf_event_groups_for_each(event, &parent_ctx->pinned_groups) { |
8dc85d54 PZ |
12006 | ret = inherit_task_group(event, parent, parent_ctx, |
12007 | child, ctxn, &inherited_all); | |
889ff015 | 12008 | if (ret) |
e7cc4865 | 12009 | goto out_unlock; |
889ff015 | 12010 | } |
b93f7978 | 12011 | |
dddd3379 TG |
12012 | /* |
12013 | * We can't hold ctx->lock when iterating the ->flexible_group list due | |
12014 | * to allocations, but we need to prevent rotation because | |
12015 | * rotate_ctx() will change the list from interrupt context. | |
12016 | */ | |
12017 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); | |
12018 | parent_ctx->rotate_disable = 1; | |
12019 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); | |
12020 | ||
6e6804d2 | 12021 | perf_event_groups_for_each(event, &parent_ctx->flexible_groups) { |
8dc85d54 PZ |
12022 | ret = inherit_task_group(event, parent, parent_ctx, |
12023 | child, ctxn, &inherited_all); | |
889ff015 | 12024 | if (ret) |
e7cc4865 | 12025 | goto out_unlock; |
564c2b21 PM |
12026 | } |
12027 | ||
dddd3379 TG |
12028 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); |
12029 | parent_ctx->rotate_disable = 0; | |
dddd3379 | 12030 | |
8dc85d54 | 12031 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 | 12032 | |
05cbaa28 | 12033 | if (child_ctx && inherited_all) { |
564c2b21 PM |
12034 | /* |
12035 | * Mark the child context as a clone of the parent | |
12036 | * context, or of whatever the parent is a clone of. | |
c5ed5145 PZ |
12037 | * |
12038 | * Note that if the parent is a clone, the holding of | |
12039 | * parent_ctx->lock avoids it from being uncloned. | |
564c2b21 | 12040 | */ |
c5ed5145 | 12041 | cloned_ctx = parent_ctx->parent_ctx; |
ad3a37de PM |
12042 | if (cloned_ctx) { |
12043 | child_ctx->parent_ctx = cloned_ctx; | |
25346b93 | 12044 | child_ctx->parent_gen = parent_ctx->parent_gen; |
564c2b21 PM |
12045 | } else { |
12046 | child_ctx->parent_ctx = parent_ctx; | |
12047 | child_ctx->parent_gen = parent_ctx->generation; | |
12048 | } | |
12049 | get_ctx(child_ctx->parent_ctx); | |
9b51f66d IM |
12050 | } |
12051 | ||
c5ed5145 | 12052 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); |
e7cc4865 | 12053 | out_unlock: |
d859e29f | 12054 | mutex_unlock(&parent_ctx->mutex); |
6ab423e0 | 12055 | |
25346b93 | 12056 | perf_unpin_context(parent_ctx); |
fe4b04fa | 12057 | put_ctx(parent_ctx); |
ad3a37de | 12058 | |
6ab423e0 | 12059 | return ret; |
9b51f66d IM |
12060 | } |
12061 | ||
8dc85d54 PZ |
12062 | /* |
12063 | * Initialize the perf_event context in task_struct | |
12064 | */ | |
12065 | int perf_event_init_task(struct task_struct *child) | |
12066 | { | |
12067 | int ctxn, ret; | |
12068 | ||
8550d7cb ON |
12069 | memset(child->perf_event_ctxp, 0, sizeof(child->perf_event_ctxp)); |
12070 | mutex_init(&child->perf_event_mutex); | |
12071 | INIT_LIST_HEAD(&child->perf_event_list); | |
12072 | ||
8dc85d54 PZ |
12073 | for_each_task_context_nr(ctxn) { |
12074 | ret = perf_event_init_context(child, ctxn); | |
6c72e350 PZ |
12075 | if (ret) { |
12076 | perf_event_free_task(child); | |
8dc85d54 | 12077 | return ret; |
6c72e350 | 12078 | } |
8dc85d54 PZ |
12079 | } |
12080 | ||
12081 | return 0; | |
12082 | } | |
12083 | ||
220b140b PM |
12084 | static void __init perf_event_init_all_cpus(void) |
12085 | { | |
b28ab83c | 12086 | struct swevent_htable *swhash; |
220b140b | 12087 | int cpu; |
220b140b | 12088 | |
a63fbed7 TG |
12089 | zalloc_cpumask_var(&perf_online_mask, GFP_KERNEL); |
12090 | ||
220b140b | 12091 | for_each_possible_cpu(cpu) { |
b28ab83c PZ |
12092 | swhash = &per_cpu(swevent_htable, cpu); |
12093 | mutex_init(&swhash->hlist_mutex); | |
2fde4f94 | 12094 | INIT_LIST_HEAD(&per_cpu(active_ctx_list, cpu)); |
f2fb6bef KL |
12095 | |
12096 | INIT_LIST_HEAD(&per_cpu(pmu_sb_events.list, cpu)); | |
12097 | raw_spin_lock_init(&per_cpu(pmu_sb_events.lock, cpu)); | |
e48c1788 | 12098 | |
058fe1c0 DCC |
12099 | #ifdef CONFIG_CGROUP_PERF |
12100 | INIT_LIST_HEAD(&per_cpu(cgrp_cpuctx_list, cpu)); | |
12101 | #endif | |
e48c1788 | 12102 | INIT_LIST_HEAD(&per_cpu(sched_cb_list, cpu)); |
220b140b PM |
12103 | } |
12104 | } | |
12105 | ||
d18bf422 | 12106 | static void perf_swevent_init_cpu(unsigned int cpu) |
0793a61d | 12107 | { |
108b02cf | 12108 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
0793a61d | 12109 | |
b28ab83c | 12110 | mutex_lock(&swhash->hlist_mutex); |
059fcd8c | 12111 | if (swhash->hlist_refcount > 0 && !swevent_hlist_deref(swhash)) { |
76e1d904 FW |
12112 | struct swevent_hlist *hlist; |
12113 | ||
b28ab83c PZ |
12114 | hlist = kzalloc_node(sizeof(*hlist), GFP_KERNEL, cpu_to_node(cpu)); |
12115 | WARN_ON(!hlist); | |
12116 | rcu_assign_pointer(swhash->swevent_hlist, hlist); | |
76e1d904 | 12117 | } |
b28ab83c | 12118 | mutex_unlock(&swhash->hlist_mutex); |
0793a61d TG |
12119 | } |
12120 | ||
2965faa5 | 12121 | #if defined CONFIG_HOTPLUG_CPU || defined CONFIG_KEXEC_CORE |
108b02cf | 12122 | static void __perf_event_exit_context(void *__info) |
0793a61d | 12123 | { |
108b02cf | 12124 | struct perf_event_context *ctx = __info; |
fae3fde6 PZ |
12125 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
12126 | struct perf_event *event; | |
0793a61d | 12127 | |
fae3fde6 | 12128 | raw_spin_lock(&ctx->lock); |
0ee098c9 | 12129 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
fae3fde6 | 12130 | list_for_each_entry(event, &ctx->event_list, event_entry) |
45a0e07a | 12131 | __perf_remove_from_context(event, cpuctx, ctx, (void *)DETACH_GROUP); |
fae3fde6 | 12132 | raw_spin_unlock(&ctx->lock); |
0793a61d | 12133 | } |
108b02cf PZ |
12134 | |
12135 | static void perf_event_exit_cpu_context(int cpu) | |
12136 | { | |
a63fbed7 | 12137 | struct perf_cpu_context *cpuctx; |
108b02cf PZ |
12138 | struct perf_event_context *ctx; |
12139 | struct pmu *pmu; | |
108b02cf | 12140 | |
a63fbed7 TG |
12141 | mutex_lock(&pmus_lock); |
12142 | list_for_each_entry(pmu, &pmus, entry) { | |
12143 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
12144 | ctx = &cpuctx->ctx; | |
108b02cf PZ |
12145 | |
12146 | mutex_lock(&ctx->mutex); | |
12147 | smp_call_function_single(cpu, __perf_event_exit_context, ctx, 1); | |
a63fbed7 | 12148 | cpuctx->online = 0; |
108b02cf PZ |
12149 | mutex_unlock(&ctx->mutex); |
12150 | } | |
a63fbed7 TG |
12151 | cpumask_clear_cpu(cpu, perf_online_mask); |
12152 | mutex_unlock(&pmus_lock); | |
108b02cf | 12153 | } |
00e16c3d TG |
12154 | #else |
12155 | ||
12156 | static void perf_event_exit_cpu_context(int cpu) { } | |
12157 | ||
12158 | #endif | |
108b02cf | 12159 | |
a63fbed7 TG |
12160 | int perf_event_init_cpu(unsigned int cpu) |
12161 | { | |
12162 | struct perf_cpu_context *cpuctx; | |
12163 | struct perf_event_context *ctx; | |
12164 | struct pmu *pmu; | |
12165 | ||
12166 | perf_swevent_init_cpu(cpu); | |
12167 | ||
12168 | mutex_lock(&pmus_lock); | |
12169 | cpumask_set_cpu(cpu, perf_online_mask); | |
12170 | list_for_each_entry(pmu, &pmus, entry) { | |
12171 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
12172 | ctx = &cpuctx->ctx; | |
12173 | ||
12174 | mutex_lock(&ctx->mutex); | |
12175 | cpuctx->online = 1; | |
12176 | mutex_unlock(&ctx->mutex); | |
12177 | } | |
12178 | mutex_unlock(&pmus_lock); | |
12179 | ||
12180 | return 0; | |
12181 | } | |
12182 | ||
00e16c3d | 12183 | int perf_event_exit_cpu(unsigned int cpu) |
0793a61d | 12184 | { |
e3703f8c | 12185 | perf_event_exit_cpu_context(cpu); |
00e16c3d | 12186 | return 0; |
0793a61d | 12187 | } |
0793a61d | 12188 | |
c277443c PZ |
12189 | static int |
12190 | perf_reboot(struct notifier_block *notifier, unsigned long val, void *v) | |
12191 | { | |
12192 | int cpu; | |
12193 | ||
12194 | for_each_online_cpu(cpu) | |
12195 | perf_event_exit_cpu(cpu); | |
12196 | ||
12197 | return NOTIFY_OK; | |
12198 | } | |
12199 | ||
12200 | /* | |
12201 | * Run the perf reboot notifier at the very last possible moment so that | |
12202 | * the generic watchdog code runs as long as possible. | |
12203 | */ | |
12204 | static struct notifier_block perf_reboot_notifier = { | |
12205 | .notifier_call = perf_reboot, | |
12206 | .priority = INT_MIN, | |
12207 | }; | |
12208 | ||
cdd6c482 | 12209 | void __init perf_event_init(void) |
0793a61d | 12210 | { |
3c502e7a JW |
12211 | int ret; |
12212 | ||
2e80a82a PZ |
12213 | idr_init(&pmu_idr); |
12214 | ||
220b140b | 12215 | perf_event_init_all_cpus(); |
b0a873eb | 12216 | init_srcu_struct(&pmus_srcu); |
2e80a82a PZ |
12217 | perf_pmu_register(&perf_swevent, "software", PERF_TYPE_SOFTWARE); |
12218 | perf_pmu_register(&perf_cpu_clock, NULL, -1); | |
12219 | perf_pmu_register(&perf_task_clock, NULL, -1); | |
b0a873eb | 12220 | perf_tp_register(); |
00e16c3d | 12221 | perf_event_init_cpu(smp_processor_id()); |
c277443c | 12222 | register_reboot_notifier(&perf_reboot_notifier); |
3c502e7a JW |
12223 | |
12224 | ret = init_hw_breakpoint(); | |
12225 | WARN(ret, "hw_breakpoint initialization failed with: %d", ret); | |
b2029520 | 12226 | |
b01c3a00 JO |
12227 | /* |
12228 | * Build time assertion that we keep the data_head at the intended | |
12229 | * location. IOW, validation we got the __reserved[] size right. | |
12230 | */ | |
12231 | BUILD_BUG_ON((offsetof(struct perf_event_mmap_page, data_head)) | |
12232 | != 1024); | |
0793a61d | 12233 | } |
abe43400 | 12234 | |
fd979c01 CS |
12235 | ssize_t perf_event_sysfs_show(struct device *dev, struct device_attribute *attr, |
12236 | char *page) | |
12237 | { | |
12238 | struct perf_pmu_events_attr *pmu_attr = | |
12239 | container_of(attr, struct perf_pmu_events_attr, attr); | |
12240 | ||
12241 | if (pmu_attr->event_str) | |
12242 | return sprintf(page, "%s\n", pmu_attr->event_str); | |
12243 | ||
12244 | return 0; | |
12245 | } | |
675965b0 | 12246 | EXPORT_SYMBOL_GPL(perf_event_sysfs_show); |
fd979c01 | 12247 | |
abe43400 PZ |
12248 | static int __init perf_event_sysfs_init(void) |
12249 | { | |
12250 | struct pmu *pmu; | |
12251 | int ret; | |
12252 | ||
12253 | mutex_lock(&pmus_lock); | |
12254 | ||
12255 | ret = bus_register(&pmu_bus); | |
12256 | if (ret) | |
12257 | goto unlock; | |
12258 | ||
12259 | list_for_each_entry(pmu, &pmus, entry) { | |
12260 | if (!pmu->name || pmu->type < 0) | |
12261 | continue; | |
12262 | ||
12263 | ret = pmu_dev_alloc(pmu); | |
12264 | WARN(ret, "Failed to register pmu: %s, reason %d\n", pmu->name, ret); | |
12265 | } | |
12266 | pmu_bus_running = 1; | |
12267 | ret = 0; | |
12268 | ||
12269 | unlock: | |
12270 | mutex_unlock(&pmus_lock); | |
12271 | ||
12272 | return ret; | |
12273 | } | |
12274 | device_initcall(perf_event_sysfs_init); | |
e5d1367f SE |
12275 | |
12276 | #ifdef CONFIG_CGROUP_PERF | |
eb95419b TH |
12277 | static struct cgroup_subsys_state * |
12278 | perf_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) | |
e5d1367f SE |
12279 | { |
12280 | struct perf_cgroup *jc; | |
e5d1367f | 12281 | |
1b15d055 | 12282 | jc = kzalloc(sizeof(*jc), GFP_KERNEL); |
e5d1367f SE |
12283 | if (!jc) |
12284 | return ERR_PTR(-ENOMEM); | |
12285 | ||
e5d1367f SE |
12286 | jc->info = alloc_percpu(struct perf_cgroup_info); |
12287 | if (!jc->info) { | |
12288 | kfree(jc); | |
12289 | return ERR_PTR(-ENOMEM); | |
12290 | } | |
12291 | ||
e5d1367f SE |
12292 | return &jc->css; |
12293 | } | |
12294 | ||
eb95419b | 12295 | static void perf_cgroup_css_free(struct cgroup_subsys_state *css) |
e5d1367f | 12296 | { |
eb95419b TH |
12297 | struct perf_cgroup *jc = container_of(css, struct perf_cgroup, css); |
12298 | ||
e5d1367f SE |
12299 | free_percpu(jc->info); |
12300 | kfree(jc); | |
12301 | } | |
12302 | ||
12303 | static int __perf_cgroup_move(void *info) | |
12304 | { | |
12305 | struct task_struct *task = info; | |
ddaaf4e2 | 12306 | rcu_read_lock(); |
e5d1367f | 12307 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT | PERF_CGROUP_SWIN); |
ddaaf4e2 | 12308 | rcu_read_unlock(); |
e5d1367f SE |
12309 | return 0; |
12310 | } | |
12311 | ||
1f7dd3e5 | 12312 | static void perf_cgroup_attach(struct cgroup_taskset *tset) |
e5d1367f | 12313 | { |
bb9d97b6 | 12314 | struct task_struct *task; |
1f7dd3e5 | 12315 | struct cgroup_subsys_state *css; |
bb9d97b6 | 12316 | |
1f7dd3e5 | 12317 | cgroup_taskset_for_each(task, css, tset) |
bb9d97b6 | 12318 | task_function_call(task, __perf_cgroup_move, task); |
e5d1367f SE |
12319 | } |
12320 | ||
073219e9 | 12321 | struct cgroup_subsys perf_event_cgrp_subsys = { |
92fb9748 TH |
12322 | .css_alloc = perf_cgroup_css_alloc, |
12323 | .css_free = perf_cgroup_css_free, | |
bb9d97b6 | 12324 | .attach = perf_cgroup_attach, |
968ebff1 TH |
12325 | /* |
12326 | * Implicitly enable on dfl hierarchy so that perf events can | |
12327 | * always be filtered by cgroup2 path as long as perf_event | |
12328 | * controller is not mounted on a legacy hierarchy. | |
12329 | */ | |
12330 | .implicit_on_dfl = true, | |
8cfd8147 | 12331 | .threaded = true, |
e5d1367f SE |
12332 | }; |
12333 | #endif /* CONFIG_CGROUP_PERF */ |