Commit | Line | Data |
---|---|---|
0793a61d | 1 | /* |
57c0c15b | 2 | * Performance events core code: |
0793a61d | 3 | * |
98144511 | 4 | * Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de> |
e7e7ee2e IM |
5 | * Copyright (C) 2008-2011 Red Hat, Inc., Ingo Molnar |
6 | * Copyright (C) 2008-2011 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com> | |
d36b6910 | 7 | * Copyright © 2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com> |
7b732a75 | 8 | * |
57c0c15b | 9 | * For licensing details see kernel-base/COPYING |
0793a61d TG |
10 | */ |
11 | ||
12 | #include <linux/fs.h> | |
b9cacc7b | 13 | #include <linux/mm.h> |
0793a61d TG |
14 | #include <linux/cpu.h> |
15 | #include <linux/smp.h> | |
2e80a82a | 16 | #include <linux/idr.h> |
04289bb9 | 17 | #include <linux/file.h> |
0793a61d | 18 | #include <linux/poll.h> |
5a0e3ad6 | 19 | #include <linux/slab.h> |
76e1d904 | 20 | #include <linux/hash.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> |
cdd6c482 | 36 | #include <linux/perf_event.h> |
6fb2915d | 37 | #include <linux/ftrace_event.h> |
3c502e7a | 38 | #include <linux/hw_breakpoint.h> |
0793a61d | 39 | |
76369139 FW |
40 | #include "internal.h" |
41 | ||
4e193bd4 TB |
42 | #include <asm/irq_regs.h> |
43 | ||
fe4b04fa | 44 | struct remote_function_call { |
e7e7ee2e IM |
45 | struct task_struct *p; |
46 | int (*func)(void *info); | |
47 | void *info; | |
48 | int ret; | |
fe4b04fa PZ |
49 | }; |
50 | ||
51 | static void remote_function(void *data) | |
52 | { | |
53 | struct remote_function_call *tfc = data; | |
54 | struct task_struct *p = tfc->p; | |
55 | ||
56 | if (p) { | |
57 | tfc->ret = -EAGAIN; | |
58 | if (task_cpu(p) != smp_processor_id() || !task_curr(p)) | |
59 | return; | |
60 | } | |
61 | ||
62 | tfc->ret = tfc->func(tfc->info); | |
63 | } | |
64 | ||
65 | /** | |
66 | * task_function_call - call a function on the cpu on which a task runs | |
67 | * @p: the task to evaluate | |
68 | * @func: the function to be called | |
69 | * @info: the function call argument | |
70 | * | |
71 | * Calls the function @func when the task is currently running. This might | |
72 | * be on the current CPU, which just calls the function directly | |
73 | * | |
74 | * returns: @func return value, or | |
75 | * -ESRCH - when the process isn't running | |
76 | * -EAGAIN - when the process moved away | |
77 | */ | |
78 | static int | |
79 | task_function_call(struct task_struct *p, int (*func) (void *info), void *info) | |
80 | { | |
81 | struct remote_function_call data = { | |
e7e7ee2e IM |
82 | .p = p, |
83 | .func = func, | |
84 | .info = info, | |
85 | .ret = -ESRCH, /* No such (running) process */ | |
fe4b04fa PZ |
86 | }; |
87 | ||
88 | if (task_curr(p)) | |
89 | smp_call_function_single(task_cpu(p), remote_function, &data, 1); | |
90 | ||
91 | return data.ret; | |
92 | } | |
93 | ||
94 | /** | |
95 | * cpu_function_call - call a function on the cpu | |
96 | * @func: the function to be called | |
97 | * @info: the function call argument | |
98 | * | |
99 | * Calls the function @func on the remote cpu. | |
100 | * | |
101 | * returns: @func return value or -ENXIO when the cpu is offline | |
102 | */ | |
103 | static int cpu_function_call(int cpu, int (*func) (void *info), void *info) | |
104 | { | |
105 | struct remote_function_call data = { | |
e7e7ee2e IM |
106 | .p = NULL, |
107 | .func = func, | |
108 | .info = info, | |
109 | .ret = -ENXIO, /* No such CPU */ | |
fe4b04fa PZ |
110 | }; |
111 | ||
112 | smp_call_function_single(cpu, remote_function, &data, 1); | |
113 | ||
114 | return data.ret; | |
115 | } | |
116 | ||
e5d1367f SE |
117 | #define PERF_FLAG_ALL (PERF_FLAG_FD_NO_GROUP |\ |
118 | PERF_FLAG_FD_OUTPUT |\ | |
119 | PERF_FLAG_PID_CGROUP) | |
120 | ||
bce38cd5 SE |
121 | /* |
122 | * branch priv levels that need permission checks | |
123 | */ | |
124 | #define PERF_SAMPLE_BRANCH_PERM_PLM \ | |
125 | (PERF_SAMPLE_BRANCH_KERNEL |\ | |
126 | PERF_SAMPLE_BRANCH_HV) | |
127 | ||
0b3fcf17 SE |
128 | enum event_type_t { |
129 | EVENT_FLEXIBLE = 0x1, | |
130 | EVENT_PINNED = 0x2, | |
131 | EVENT_ALL = EVENT_FLEXIBLE | EVENT_PINNED, | |
132 | }; | |
133 | ||
e5d1367f SE |
134 | /* |
135 | * perf_sched_events : >0 events exist | |
136 | * perf_cgroup_events: >0 per-cpu cgroup events exist on this cpu | |
137 | */ | |
c5905afb | 138 | struct static_key_deferred perf_sched_events __read_mostly; |
e5d1367f | 139 | static DEFINE_PER_CPU(atomic_t, perf_cgroup_events); |
d010b332 | 140 | static DEFINE_PER_CPU(atomic_t, perf_branch_stack_events); |
e5d1367f | 141 | |
cdd6c482 IM |
142 | static atomic_t nr_mmap_events __read_mostly; |
143 | static atomic_t nr_comm_events __read_mostly; | |
144 | static atomic_t nr_task_events __read_mostly; | |
9ee318a7 | 145 | |
108b02cf PZ |
146 | static LIST_HEAD(pmus); |
147 | static DEFINE_MUTEX(pmus_lock); | |
148 | static struct srcu_struct pmus_srcu; | |
149 | ||
0764771d | 150 | /* |
cdd6c482 | 151 | * perf event paranoia level: |
0fbdea19 IM |
152 | * -1 - not paranoid at all |
153 | * 0 - disallow raw tracepoint access for unpriv | |
cdd6c482 | 154 | * 1 - disallow cpu events for unpriv |
0fbdea19 | 155 | * 2 - disallow kernel profiling for unpriv |
0764771d | 156 | */ |
cdd6c482 | 157 | int sysctl_perf_event_paranoid __read_mostly = 1; |
0764771d | 158 | |
20443384 FW |
159 | /* Minimum for 512 kiB + 1 user control page */ |
160 | int sysctl_perf_event_mlock __read_mostly = 512 + (PAGE_SIZE / 1024); /* 'free' kiB per user */ | |
df58ab24 PZ |
161 | |
162 | /* | |
cdd6c482 | 163 | * max perf event sample rate |
df58ab24 | 164 | */ |
163ec435 PZ |
165 | #define DEFAULT_MAX_SAMPLE_RATE 100000 |
166 | int sysctl_perf_event_sample_rate __read_mostly = DEFAULT_MAX_SAMPLE_RATE; | |
167 | static int max_samples_per_tick __read_mostly = | |
168 | DIV_ROUND_UP(DEFAULT_MAX_SAMPLE_RATE, HZ); | |
169 | ||
170 | int perf_proc_update_handler(struct ctl_table *table, int write, | |
171 | void __user *buffer, size_t *lenp, | |
172 | loff_t *ppos) | |
173 | { | |
174 | int ret = proc_dointvec(table, write, buffer, lenp, ppos); | |
175 | ||
176 | if (ret || !write) | |
177 | return ret; | |
178 | ||
179 | max_samples_per_tick = DIV_ROUND_UP(sysctl_perf_event_sample_rate, HZ); | |
180 | ||
181 | return 0; | |
182 | } | |
1ccd1549 | 183 | |
cdd6c482 | 184 | static atomic64_t perf_event_id; |
a96bbc16 | 185 | |
0b3fcf17 SE |
186 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, |
187 | enum event_type_t event_type); | |
188 | ||
189 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
190 | enum event_type_t event_type, |
191 | struct task_struct *task); | |
192 | ||
193 | static void update_context_time(struct perf_event_context *ctx); | |
194 | static u64 perf_event_time(struct perf_event *event); | |
0b3fcf17 | 195 | |
10c6db11 PZ |
196 | static void ring_buffer_attach(struct perf_event *event, |
197 | struct ring_buffer *rb); | |
198 | ||
cdd6c482 | 199 | void __weak perf_event_print_debug(void) { } |
0793a61d | 200 | |
84c79910 | 201 | extern __weak const char *perf_pmu_name(void) |
0793a61d | 202 | { |
84c79910 | 203 | return "pmu"; |
0793a61d TG |
204 | } |
205 | ||
0b3fcf17 SE |
206 | static inline u64 perf_clock(void) |
207 | { | |
208 | return local_clock(); | |
209 | } | |
210 | ||
e5d1367f SE |
211 | static inline struct perf_cpu_context * |
212 | __get_cpu_context(struct perf_event_context *ctx) | |
213 | { | |
214 | return this_cpu_ptr(ctx->pmu->pmu_cpu_context); | |
215 | } | |
216 | ||
facc4307 PZ |
217 | static void perf_ctx_lock(struct perf_cpu_context *cpuctx, |
218 | struct perf_event_context *ctx) | |
219 | { | |
220 | raw_spin_lock(&cpuctx->ctx.lock); | |
221 | if (ctx) | |
222 | raw_spin_lock(&ctx->lock); | |
223 | } | |
224 | ||
225 | static void perf_ctx_unlock(struct perf_cpu_context *cpuctx, | |
226 | struct perf_event_context *ctx) | |
227 | { | |
228 | if (ctx) | |
229 | raw_spin_unlock(&ctx->lock); | |
230 | raw_spin_unlock(&cpuctx->ctx.lock); | |
231 | } | |
232 | ||
e5d1367f SE |
233 | #ifdef CONFIG_CGROUP_PERF |
234 | ||
3f7cce3c SE |
235 | /* |
236 | * Must ensure cgroup is pinned (css_get) before calling | |
237 | * this function. In other words, we cannot call this function | |
238 | * if there is no cgroup event for the current CPU context. | |
239 | */ | |
e5d1367f SE |
240 | static inline struct perf_cgroup * |
241 | perf_cgroup_from_task(struct task_struct *task) | |
242 | { | |
243 | return container_of(task_subsys_state(task, perf_subsys_id), | |
244 | struct perf_cgroup, css); | |
245 | } | |
246 | ||
247 | static inline bool | |
248 | perf_cgroup_match(struct perf_event *event) | |
249 | { | |
250 | struct perf_event_context *ctx = event->ctx; | |
251 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
252 | ||
253 | return !event->cgrp || event->cgrp == cpuctx->cgrp; | |
254 | } | |
255 | ||
9c5da09d | 256 | static inline bool perf_tryget_cgroup(struct perf_event *event) |
e5d1367f | 257 | { |
9c5da09d | 258 | return css_tryget(&event->cgrp->css); |
e5d1367f SE |
259 | } |
260 | ||
261 | static inline void perf_put_cgroup(struct perf_event *event) | |
262 | { | |
263 | css_put(&event->cgrp->css); | |
264 | } | |
265 | ||
266 | static inline void perf_detach_cgroup(struct perf_event *event) | |
267 | { | |
268 | perf_put_cgroup(event); | |
269 | event->cgrp = NULL; | |
270 | } | |
271 | ||
272 | static inline int is_cgroup_event(struct perf_event *event) | |
273 | { | |
274 | return event->cgrp != NULL; | |
275 | } | |
276 | ||
277 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
278 | { | |
279 | struct perf_cgroup_info *t; | |
280 | ||
281 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
282 | return t->time; | |
283 | } | |
284 | ||
285 | static inline void __update_cgrp_time(struct perf_cgroup *cgrp) | |
286 | { | |
287 | struct perf_cgroup_info *info; | |
288 | u64 now; | |
289 | ||
290 | now = perf_clock(); | |
291 | ||
292 | info = this_cpu_ptr(cgrp->info); | |
293 | ||
294 | info->time += now - info->timestamp; | |
295 | info->timestamp = now; | |
296 | } | |
297 | ||
298 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
299 | { | |
300 | struct perf_cgroup *cgrp_out = cpuctx->cgrp; | |
301 | if (cgrp_out) | |
302 | __update_cgrp_time(cgrp_out); | |
303 | } | |
304 | ||
305 | static inline void update_cgrp_time_from_event(struct perf_event *event) | |
306 | { | |
3f7cce3c SE |
307 | struct perf_cgroup *cgrp; |
308 | ||
e5d1367f | 309 | /* |
3f7cce3c SE |
310 | * ensure we access cgroup data only when needed and |
311 | * when we know the cgroup is pinned (css_get) | |
e5d1367f | 312 | */ |
3f7cce3c | 313 | if (!is_cgroup_event(event)) |
e5d1367f SE |
314 | return; |
315 | ||
3f7cce3c SE |
316 | cgrp = perf_cgroup_from_task(current); |
317 | /* | |
318 | * Do not update time when cgroup is not active | |
319 | */ | |
320 | if (cgrp == event->cgrp) | |
321 | __update_cgrp_time(event->cgrp); | |
e5d1367f SE |
322 | } |
323 | ||
324 | static inline void | |
3f7cce3c SE |
325 | perf_cgroup_set_timestamp(struct task_struct *task, |
326 | struct perf_event_context *ctx) | |
e5d1367f SE |
327 | { |
328 | struct perf_cgroup *cgrp; | |
329 | struct perf_cgroup_info *info; | |
330 | ||
3f7cce3c SE |
331 | /* |
332 | * ctx->lock held by caller | |
333 | * ensure we do not access cgroup data | |
334 | * unless we have the cgroup pinned (css_get) | |
335 | */ | |
336 | if (!task || !ctx->nr_cgroups) | |
e5d1367f SE |
337 | return; |
338 | ||
339 | cgrp = perf_cgroup_from_task(task); | |
340 | info = this_cpu_ptr(cgrp->info); | |
3f7cce3c | 341 | info->timestamp = ctx->timestamp; |
e5d1367f SE |
342 | } |
343 | ||
344 | #define PERF_CGROUP_SWOUT 0x1 /* cgroup switch out every event */ | |
345 | #define PERF_CGROUP_SWIN 0x2 /* cgroup switch in events based on task */ | |
346 | ||
347 | /* | |
348 | * reschedule events based on the cgroup constraint of task. | |
349 | * | |
350 | * mode SWOUT : schedule out everything | |
351 | * mode SWIN : schedule in based on cgroup for next | |
352 | */ | |
353 | void perf_cgroup_switch(struct task_struct *task, int mode) | |
354 | { | |
355 | struct perf_cpu_context *cpuctx; | |
356 | struct pmu *pmu; | |
357 | unsigned long flags; | |
358 | ||
359 | /* | |
360 | * disable interrupts to avoid geting nr_cgroup | |
361 | * changes via __perf_event_disable(). Also | |
362 | * avoids preemption. | |
363 | */ | |
364 | local_irq_save(flags); | |
365 | ||
366 | /* | |
367 | * we reschedule only in the presence of cgroup | |
368 | * constrained events. | |
369 | */ | |
370 | rcu_read_lock(); | |
371 | ||
372 | list_for_each_entry_rcu(pmu, &pmus, entry) { | |
e5d1367f SE |
373 | cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
374 | ||
e5d1367f SE |
375 | /* |
376 | * perf_cgroup_events says at least one | |
377 | * context on this CPU has cgroup events. | |
378 | * | |
379 | * ctx->nr_cgroups reports the number of cgroup | |
380 | * events for a context. | |
381 | */ | |
382 | if (cpuctx->ctx.nr_cgroups > 0) { | |
facc4307 PZ |
383 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
384 | perf_pmu_disable(cpuctx->ctx.pmu); | |
e5d1367f SE |
385 | |
386 | if (mode & PERF_CGROUP_SWOUT) { | |
387 | cpu_ctx_sched_out(cpuctx, EVENT_ALL); | |
388 | /* | |
389 | * must not be done before ctxswout due | |
390 | * to event_filter_match() in event_sched_out() | |
391 | */ | |
392 | cpuctx->cgrp = NULL; | |
393 | } | |
394 | ||
395 | if (mode & PERF_CGROUP_SWIN) { | |
e566b76e | 396 | WARN_ON_ONCE(cpuctx->cgrp); |
e5d1367f SE |
397 | /* set cgrp before ctxsw in to |
398 | * allow event_filter_match() to not | |
399 | * have to pass task around | |
400 | */ | |
401 | cpuctx->cgrp = perf_cgroup_from_task(task); | |
402 | cpu_ctx_sched_in(cpuctx, EVENT_ALL, task); | |
403 | } | |
facc4307 PZ |
404 | perf_pmu_enable(cpuctx->ctx.pmu); |
405 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
e5d1367f | 406 | } |
e5d1367f SE |
407 | } |
408 | ||
409 | rcu_read_unlock(); | |
410 | ||
411 | local_irq_restore(flags); | |
412 | } | |
413 | ||
a8d757ef SE |
414 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
415 | struct task_struct *next) | |
e5d1367f | 416 | { |
a8d757ef SE |
417 | struct perf_cgroup *cgrp1; |
418 | struct perf_cgroup *cgrp2 = NULL; | |
419 | ||
420 | /* | |
421 | * we come here when we know perf_cgroup_events > 0 | |
422 | */ | |
423 | cgrp1 = perf_cgroup_from_task(task); | |
424 | ||
425 | /* | |
426 | * next is NULL when called from perf_event_enable_on_exec() | |
427 | * that will systematically cause a cgroup_switch() | |
428 | */ | |
429 | if (next) | |
430 | cgrp2 = perf_cgroup_from_task(next); | |
431 | ||
432 | /* | |
433 | * only schedule out current cgroup events if we know | |
434 | * that we are switching to a different cgroup. Otherwise, | |
435 | * do no touch the cgroup events. | |
436 | */ | |
437 | if (cgrp1 != cgrp2) | |
438 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT); | |
e5d1367f SE |
439 | } |
440 | ||
a8d757ef SE |
441 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
442 | struct task_struct *task) | |
e5d1367f | 443 | { |
a8d757ef SE |
444 | struct perf_cgroup *cgrp1; |
445 | struct perf_cgroup *cgrp2 = NULL; | |
446 | ||
447 | /* | |
448 | * we come here when we know perf_cgroup_events > 0 | |
449 | */ | |
450 | cgrp1 = perf_cgroup_from_task(task); | |
451 | ||
452 | /* prev can never be NULL */ | |
453 | cgrp2 = perf_cgroup_from_task(prev); | |
454 | ||
455 | /* | |
456 | * only need to schedule in cgroup events if we are changing | |
457 | * cgroup during ctxsw. Cgroup events were not scheduled | |
458 | * out of ctxsw out if that was not the case. | |
459 | */ | |
460 | if (cgrp1 != cgrp2) | |
461 | perf_cgroup_switch(task, PERF_CGROUP_SWIN); | |
e5d1367f SE |
462 | } |
463 | ||
464 | static inline int perf_cgroup_connect(int fd, struct perf_event *event, | |
465 | struct perf_event_attr *attr, | |
466 | struct perf_event *group_leader) | |
467 | { | |
468 | struct perf_cgroup *cgrp; | |
469 | struct cgroup_subsys_state *css; | |
470 | struct file *file; | |
471 | int ret = 0, fput_needed; | |
472 | ||
473 | file = fget_light(fd, &fput_needed); | |
474 | if (!file) | |
475 | return -EBADF; | |
476 | ||
477 | css = cgroup_css_from_dir(file, perf_subsys_id); | |
3db272c0 LZ |
478 | if (IS_ERR(css)) { |
479 | ret = PTR_ERR(css); | |
480 | goto out; | |
481 | } | |
e5d1367f SE |
482 | |
483 | cgrp = container_of(css, struct perf_cgroup, css); | |
484 | event->cgrp = cgrp; | |
485 | ||
f75e18cb | 486 | /* must be done before we fput() the file */ |
9c5da09d SQ |
487 | if (!perf_tryget_cgroup(event)) { |
488 | event->cgrp = NULL; | |
489 | ret = -ENOENT; | |
490 | goto out; | |
491 | } | |
f75e18cb | 492 | |
e5d1367f SE |
493 | /* |
494 | * all events in a group must monitor | |
495 | * the same cgroup because a task belongs | |
496 | * to only one perf cgroup at a time | |
497 | */ | |
498 | if (group_leader && group_leader->cgrp != cgrp) { | |
499 | perf_detach_cgroup(event); | |
500 | ret = -EINVAL; | |
e5d1367f | 501 | } |
3db272c0 | 502 | out: |
e5d1367f SE |
503 | fput_light(file, fput_needed); |
504 | return ret; | |
505 | } | |
506 | ||
507 | static inline void | |
508 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
509 | { | |
510 | struct perf_cgroup_info *t; | |
511 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
512 | event->shadow_ctx_time = now - t->timestamp; | |
513 | } | |
514 | ||
515 | static inline void | |
516 | perf_cgroup_defer_enabled(struct perf_event *event) | |
517 | { | |
518 | /* | |
519 | * when the current task's perf cgroup does not match | |
520 | * the event's, we need to remember to call the | |
521 | * perf_mark_enable() function the first time a task with | |
522 | * a matching perf cgroup is scheduled in. | |
523 | */ | |
524 | if (is_cgroup_event(event) && !perf_cgroup_match(event)) | |
525 | event->cgrp_defer_enabled = 1; | |
526 | } | |
527 | ||
528 | static inline void | |
529 | perf_cgroup_mark_enabled(struct perf_event *event, | |
530 | struct perf_event_context *ctx) | |
531 | { | |
532 | struct perf_event *sub; | |
533 | u64 tstamp = perf_event_time(event); | |
534 | ||
535 | if (!event->cgrp_defer_enabled) | |
536 | return; | |
537 | ||
538 | event->cgrp_defer_enabled = 0; | |
539 | ||
540 | event->tstamp_enabled = tstamp - event->total_time_enabled; | |
541 | list_for_each_entry(sub, &event->sibling_list, group_entry) { | |
542 | if (sub->state >= PERF_EVENT_STATE_INACTIVE) { | |
543 | sub->tstamp_enabled = tstamp - sub->total_time_enabled; | |
544 | sub->cgrp_defer_enabled = 0; | |
545 | } | |
546 | } | |
547 | } | |
548 | #else /* !CONFIG_CGROUP_PERF */ | |
549 | ||
550 | static inline bool | |
551 | perf_cgroup_match(struct perf_event *event) | |
552 | { | |
553 | return true; | |
554 | } | |
555 | ||
556 | static inline void perf_detach_cgroup(struct perf_event *event) | |
557 | {} | |
558 | ||
559 | static inline int is_cgroup_event(struct perf_event *event) | |
560 | { | |
561 | return 0; | |
562 | } | |
563 | ||
564 | static inline u64 perf_cgroup_event_cgrp_time(struct perf_event *event) | |
565 | { | |
566 | return 0; | |
567 | } | |
568 | ||
569 | static inline void update_cgrp_time_from_event(struct perf_event *event) | |
570 | { | |
571 | } | |
572 | ||
573 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
574 | { | |
575 | } | |
576 | ||
a8d757ef SE |
577 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
578 | struct task_struct *next) | |
e5d1367f SE |
579 | { |
580 | } | |
581 | ||
a8d757ef SE |
582 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
583 | struct task_struct *task) | |
e5d1367f SE |
584 | { |
585 | } | |
586 | ||
587 | static inline int perf_cgroup_connect(pid_t pid, struct perf_event *event, | |
588 | struct perf_event_attr *attr, | |
589 | struct perf_event *group_leader) | |
590 | { | |
591 | return -EINVAL; | |
592 | } | |
593 | ||
594 | static inline void | |
3f7cce3c SE |
595 | perf_cgroup_set_timestamp(struct task_struct *task, |
596 | struct perf_event_context *ctx) | |
e5d1367f SE |
597 | { |
598 | } | |
599 | ||
600 | void | |
601 | perf_cgroup_switch(struct task_struct *task, struct task_struct *next) | |
602 | { | |
603 | } | |
604 | ||
605 | static inline void | |
606 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
607 | { | |
608 | } | |
609 | ||
610 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
611 | { | |
612 | return 0; | |
613 | } | |
614 | ||
615 | static inline void | |
616 | perf_cgroup_defer_enabled(struct perf_event *event) | |
617 | { | |
618 | } | |
619 | ||
620 | static inline void | |
621 | perf_cgroup_mark_enabled(struct perf_event *event, | |
622 | struct perf_event_context *ctx) | |
623 | { | |
624 | } | |
625 | #endif | |
626 | ||
33696fc0 | 627 | void perf_pmu_disable(struct pmu *pmu) |
9e35ad38 | 628 | { |
33696fc0 PZ |
629 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
630 | if (!(*count)++) | |
631 | pmu->pmu_disable(pmu); | |
9e35ad38 | 632 | } |
9e35ad38 | 633 | |
33696fc0 | 634 | void perf_pmu_enable(struct pmu *pmu) |
9e35ad38 | 635 | { |
33696fc0 PZ |
636 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
637 | if (!--(*count)) | |
638 | pmu->pmu_enable(pmu); | |
9e35ad38 | 639 | } |
9e35ad38 | 640 | |
e9d2b064 PZ |
641 | static DEFINE_PER_CPU(struct list_head, rotation_list); |
642 | ||
643 | /* | |
644 | * perf_pmu_rotate_start() and perf_rotate_context() are fully serialized | |
645 | * because they're strictly cpu affine and rotate_start is called with IRQs | |
646 | * disabled, while rotate_context is called from IRQ context. | |
647 | */ | |
108b02cf | 648 | static void perf_pmu_rotate_start(struct pmu *pmu) |
9e35ad38 | 649 | { |
108b02cf | 650 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
e9d2b064 | 651 | struct list_head *head = &__get_cpu_var(rotation_list); |
b5ab4cd5 | 652 | |
e9d2b064 | 653 | WARN_ON(!irqs_disabled()); |
b5ab4cd5 | 654 | |
e9d2b064 PZ |
655 | if (list_empty(&cpuctx->rotation_list)) |
656 | list_add(&cpuctx->rotation_list, head); | |
9e35ad38 | 657 | } |
9e35ad38 | 658 | |
cdd6c482 | 659 | static void get_ctx(struct perf_event_context *ctx) |
a63eaf34 | 660 | { |
e5289d4a | 661 | WARN_ON(!atomic_inc_not_zero(&ctx->refcount)); |
a63eaf34 PM |
662 | } |
663 | ||
cdd6c482 | 664 | static void put_ctx(struct perf_event_context *ctx) |
a63eaf34 | 665 | { |
564c2b21 PM |
666 | if (atomic_dec_and_test(&ctx->refcount)) { |
667 | if (ctx->parent_ctx) | |
668 | put_ctx(ctx->parent_ctx); | |
c93f7669 PM |
669 | if (ctx->task) |
670 | put_task_struct(ctx->task); | |
cb796ff3 | 671 | kfree_rcu(ctx, rcu_head); |
564c2b21 | 672 | } |
a63eaf34 PM |
673 | } |
674 | ||
cdd6c482 | 675 | static void unclone_ctx(struct perf_event_context *ctx) |
71a851b4 PZ |
676 | { |
677 | if (ctx->parent_ctx) { | |
678 | put_ctx(ctx->parent_ctx); | |
679 | ctx->parent_ctx = NULL; | |
680 | } | |
681 | } | |
682 | ||
6844c09d ACM |
683 | static u32 perf_event_pid(struct perf_event *event, struct task_struct *p) |
684 | { | |
685 | /* | |
686 | * only top level events have the pid namespace they were created in | |
687 | */ | |
688 | if (event->parent) | |
689 | event = event->parent; | |
690 | ||
691 | return task_tgid_nr_ns(p, event->ns); | |
692 | } | |
693 | ||
694 | static u32 perf_event_tid(struct perf_event *event, struct task_struct *p) | |
695 | { | |
696 | /* | |
697 | * only top level events have the pid namespace they were created in | |
698 | */ | |
699 | if (event->parent) | |
700 | event = event->parent; | |
701 | ||
702 | return task_pid_nr_ns(p, event->ns); | |
703 | } | |
704 | ||
7f453c24 | 705 | /* |
cdd6c482 | 706 | * If we inherit events we want to return the parent event id |
7f453c24 PZ |
707 | * to userspace. |
708 | */ | |
cdd6c482 | 709 | static u64 primary_event_id(struct perf_event *event) |
7f453c24 | 710 | { |
cdd6c482 | 711 | u64 id = event->id; |
7f453c24 | 712 | |
cdd6c482 IM |
713 | if (event->parent) |
714 | id = event->parent->id; | |
7f453c24 PZ |
715 | |
716 | return id; | |
717 | } | |
718 | ||
25346b93 | 719 | /* |
cdd6c482 | 720 | * Get the perf_event_context for a task and lock it. |
25346b93 PM |
721 | * This has to cope with with the fact that until it is locked, |
722 | * the context could get moved to another task. | |
723 | */ | |
cdd6c482 | 724 | static struct perf_event_context * |
8dc85d54 | 725 | perf_lock_task_context(struct task_struct *task, int ctxn, unsigned long *flags) |
25346b93 | 726 | { |
cdd6c482 | 727 | struct perf_event_context *ctx; |
25346b93 PM |
728 | |
729 | rcu_read_lock(); | |
9ed6060d | 730 | retry: |
8dc85d54 | 731 | ctx = rcu_dereference(task->perf_event_ctxp[ctxn]); |
25346b93 PM |
732 | if (ctx) { |
733 | /* | |
734 | * If this context is a clone of another, it might | |
735 | * get swapped for another underneath us by | |
cdd6c482 | 736 | * perf_event_task_sched_out, though the |
25346b93 PM |
737 | * rcu_read_lock() protects us from any context |
738 | * getting freed. Lock the context and check if it | |
739 | * got swapped before we could get the lock, and retry | |
740 | * if so. If we locked the right context, then it | |
741 | * can't get swapped on us any more. | |
742 | */ | |
e625cce1 | 743 | raw_spin_lock_irqsave(&ctx->lock, *flags); |
8dc85d54 | 744 | if (ctx != rcu_dereference(task->perf_event_ctxp[ctxn])) { |
e625cce1 | 745 | raw_spin_unlock_irqrestore(&ctx->lock, *flags); |
25346b93 PM |
746 | goto retry; |
747 | } | |
b49a9e7e PZ |
748 | |
749 | if (!atomic_inc_not_zero(&ctx->refcount)) { | |
e625cce1 | 750 | raw_spin_unlock_irqrestore(&ctx->lock, *flags); |
b49a9e7e PZ |
751 | ctx = NULL; |
752 | } | |
25346b93 PM |
753 | } |
754 | rcu_read_unlock(); | |
755 | return ctx; | |
756 | } | |
757 | ||
758 | /* | |
759 | * Get the context for a task and increment its pin_count so it | |
760 | * can't get swapped to another task. This also increments its | |
761 | * reference count so that the context can't get freed. | |
762 | */ | |
8dc85d54 PZ |
763 | static struct perf_event_context * |
764 | perf_pin_task_context(struct task_struct *task, int ctxn) | |
25346b93 | 765 | { |
cdd6c482 | 766 | struct perf_event_context *ctx; |
25346b93 PM |
767 | unsigned long flags; |
768 | ||
8dc85d54 | 769 | ctx = perf_lock_task_context(task, ctxn, &flags); |
25346b93 PM |
770 | if (ctx) { |
771 | ++ctx->pin_count; | |
e625cce1 | 772 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
773 | } |
774 | return ctx; | |
775 | } | |
776 | ||
cdd6c482 | 777 | static void perf_unpin_context(struct perf_event_context *ctx) |
25346b93 PM |
778 | { |
779 | unsigned long flags; | |
780 | ||
e625cce1 | 781 | raw_spin_lock_irqsave(&ctx->lock, flags); |
25346b93 | 782 | --ctx->pin_count; |
e625cce1 | 783 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
784 | } |
785 | ||
f67218c3 PZ |
786 | /* |
787 | * Update the record of the current time in a context. | |
788 | */ | |
789 | static void update_context_time(struct perf_event_context *ctx) | |
790 | { | |
791 | u64 now = perf_clock(); | |
792 | ||
793 | ctx->time += now - ctx->timestamp; | |
794 | ctx->timestamp = now; | |
795 | } | |
796 | ||
4158755d SE |
797 | static u64 perf_event_time(struct perf_event *event) |
798 | { | |
799 | struct perf_event_context *ctx = event->ctx; | |
e5d1367f SE |
800 | |
801 | if (is_cgroup_event(event)) | |
802 | return perf_cgroup_event_time(event); | |
803 | ||
4158755d SE |
804 | return ctx ? ctx->time : 0; |
805 | } | |
806 | ||
f67218c3 PZ |
807 | /* |
808 | * Update the total_time_enabled and total_time_running fields for a event. | |
b7526f0c | 809 | * The caller of this function needs to hold the ctx->lock. |
f67218c3 PZ |
810 | */ |
811 | static void update_event_times(struct perf_event *event) | |
812 | { | |
813 | struct perf_event_context *ctx = event->ctx; | |
814 | u64 run_end; | |
815 | ||
816 | if (event->state < PERF_EVENT_STATE_INACTIVE || | |
817 | event->group_leader->state < PERF_EVENT_STATE_INACTIVE) | |
818 | return; | |
e5d1367f SE |
819 | /* |
820 | * in cgroup mode, time_enabled represents | |
821 | * the time the event was enabled AND active | |
822 | * tasks were in the monitored cgroup. This is | |
823 | * independent of the activity of the context as | |
824 | * there may be a mix of cgroup and non-cgroup events. | |
825 | * | |
826 | * That is why we treat cgroup events differently | |
827 | * here. | |
828 | */ | |
829 | if (is_cgroup_event(event)) | |
46cd6a7f | 830 | run_end = perf_cgroup_event_time(event); |
e5d1367f SE |
831 | else if (ctx->is_active) |
832 | run_end = ctx->time; | |
acd1d7c1 PZ |
833 | else |
834 | run_end = event->tstamp_stopped; | |
835 | ||
836 | event->total_time_enabled = run_end - event->tstamp_enabled; | |
f67218c3 PZ |
837 | |
838 | if (event->state == PERF_EVENT_STATE_INACTIVE) | |
839 | run_end = event->tstamp_stopped; | |
840 | else | |
4158755d | 841 | run_end = perf_event_time(event); |
f67218c3 PZ |
842 | |
843 | event->total_time_running = run_end - event->tstamp_running; | |
e5d1367f | 844 | |
f67218c3 PZ |
845 | } |
846 | ||
96c21a46 PZ |
847 | /* |
848 | * Update total_time_enabled and total_time_running for all events in a group. | |
849 | */ | |
850 | static void update_group_times(struct perf_event *leader) | |
851 | { | |
852 | struct perf_event *event; | |
853 | ||
854 | update_event_times(leader); | |
855 | list_for_each_entry(event, &leader->sibling_list, group_entry) | |
856 | update_event_times(event); | |
857 | } | |
858 | ||
889ff015 FW |
859 | static struct list_head * |
860 | ctx_group_list(struct perf_event *event, struct perf_event_context *ctx) | |
861 | { | |
862 | if (event->attr.pinned) | |
863 | return &ctx->pinned_groups; | |
864 | else | |
865 | return &ctx->flexible_groups; | |
866 | } | |
867 | ||
fccc714b | 868 | /* |
cdd6c482 | 869 | * Add a event from the lists for its context. |
fccc714b PZ |
870 | * Must be called with ctx->mutex and ctx->lock held. |
871 | */ | |
04289bb9 | 872 | static void |
cdd6c482 | 873 | list_add_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 874 | { |
8a49542c PZ |
875 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); |
876 | event->attach_state |= PERF_ATTACH_CONTEXT; | |
04289bb9 IM |
877 | |
878 | /* | |
8a49542c PZ |
879 | * If we're a stand alone event or group leader, we go to the context |
880 | * list, group events are kept attached to the group so that | |
881 | * perf_group_detach can, at all times, locate all siblings. | |
04289bb9 | 882 | */ |
8a49542c | 883 | if (event->group_leader == event) { |
889ff015 FW |
884 | struct list_head *list; |
885 | ||
d6f962b5 FW |
886 | if (is_software_event(event)) |
887 | event->group_flags |= PERF_GROUP_SOFTWARE; | |
888 | ||
889ff015 FW |
889 | list = ctx_group_list(event, ctx); |
890 | list_add_tail(&event->group_entry, list); | |
5c148194 | 891 | } |
592903cd | 892 | |
08309379 | 893 | if (is_cgroup_event(event)) |
e5d1367f | 894 | ctx->nr_cgroups++; |
e5d1367f | 895 | |
d010b332 SE |
896 | if (has_branch_stack(event)) |
897 | ctx->nr_branch_stack++; | |
898 | ||
cdd6c482 | 899 | list_add_rcu(&event->event_entry, &ctx->event_list); |
b5ab4cd5 | 900 | if (!ctx->nr_events) |
108b02cf | 901 | perf_pmu_rotate_start(ctx->pmu); |
cdd6c482 IM |
902 | ctx->nr_events++; |
903 | if (event->attr.inherit_stat) | |
bfbd3381 | 904 | ctx->nr_stat++; |
04289bb9 IM |
905 | } |
906 | ||
c320c7b7 ACM |
907 | /* |
908 | * Called at perf_event creation and when events are attached/detached from a | |
909 | * group. | |
910 | */ | |
911 | static void perf_event__read_size(struct perf_event *event) | |
912 | { | |
913 | int entry = sizeof(u64); /* value */ | |
914 | int size = 0; | |
915 | int nr = 1; | |
916 | ||
917 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
918 | size += sizeof(u64); | |
919 | ||
920 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
921 | size += sizeof(u64); | |
922 | ||
923 | if (event->attr.read_format & PERF_FORMAT_ID) | |
924 | entry += sizeof(u64); | |
925 | ||
926 | if (event->attr.read_format & PERF_FORMAT_GROUP) { | |
927 | nr += event->group_leader->nr_siblings; | |
928 | size += sizeof(u64); | |
929 | } | |
930 | ||
931 | size += entry * nr; | |
932 | event->read_size = size; | |
933 | } | |
934 | ||
935 | static void perf_event__header_size(struct perf_event *event) | |
936 | { | |
937 | struct perf_sample_data *data; | |
938 | u64 sample_type = event->attr.sample_type; | |
939 | u16 size = 0; | |
940 | ||
941 | perf_event__read_size(event); | |
942 | ||
943 | if (sample_type & PERF_SAMPLE_IP) | |
944 | size += sizeof(data->ip); | |
945 | ||
6844c09d ACM |
946 | if (sample_type & PERF_SAMPLE_ADDR) |
947 | size += sizeof(data->addr); | |
948 | ||
949 | if (sample_type & PERF_SAMPLE_PERIOD) | |
950 | size += sizeof(data->period); | |
951 | ||
952 | if (sample_type & PERF_SAMPLE_READ) | |
953 | size += event->read_size; | |
954 | ||
955 | event->header_size = size; | |
956 | } | |
957 | ||
958 | static void perf_event__id_header_size(struct perf_event *event) | |
959 | { | |
960 | struct perf_sample_data *data; | |
961 | u64 sample_type = event->attr.sample_type; | |
962 | u16 size = 0; | |
963 | ||
c320c7b7 ACM |
964 | if (sample_type & PERF_SAMPLE_TID) |
965 | size += sizeof(data->tid_entry); | |
966 | ||
967 | if (sample_type & PERF_SAMPLE_TIME) | |
968 | size += sizeof(data->time); | |
969 | ||
c320c7b7 ACM |
970 | if (sample_type & PERF_SAMPLE_ID) |
971 | size += sizeof(data->id); | |
972 | ||
973 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
974 | size += sizeof(data->stream_id); | |
975 | ||
976 | if (sample_type & PERF_SAMPLE_CPU) | |
977 | size += sizeof(data->cpu_entry); | |
978 | ||
6844c09d | 979 | event->id_header_size = size; |
c320c7b7 ACM |
980 | } |
981 | ||
8a49542c PZ |
982 | static void perf_group_attach(struct perf_event *event) |
983 | { | |
c320c7b7 | 984 | struct perf_event *group_leader = event->group_leader, *pos; |
8a49542c | 985 | |
74c3337c PZ |
986 | /* |
987 | * We can have double attach due to group movement in perf_event_open. | |
988 | */ | |
989 | if (event->attach_state & PERF_ATTACH_GROUP) | |
990 | return; | |
991 | ||
8a49542c PZ |
992 | event->attach_state |= PERF_ATTACH_GROUP; |
993 | ||
994 | if (group_leader == event) | |
995 | return; | |
996 | ||
997 | if (group_leader->group_flags & PERF_GROUP_SOFTWARE && | |
998 | !is_software_event(event)) | |
999 | group_leader->group_flags &= ~PERF_GROUP_SOFTWARE; | |
1000 | ||
1001 | list_add_tail(&event->group_entry, &group_leader->sibling_list); | |
1002 | group_leader->nr_siblings++; | |
c320c7b7 ACM |
1003 | |
1004 | perf_event__header_size(group_leader); | |
1005 | ||
1006 | list_for_each_entry(pos, &group_leader->sibling_list, group_entry) | |
1007 | perf_event__header_size(pos); | |
8a49542c PZ |
1008 | } |
1009 | ||
a63eaf34 | 1010 | /* |
cdd6c482 | 1011 | * Remove a event from the lists for its context. |
fccc714b | 1012 | * Must be called with ctx->mutex and ctx->lock held. |
a63eaf34 | 1013 | */ |
04289bb9 | 1014 | static void |
cdd6c482 | 1015 | list_del_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1016 | { |
68cacd29 | 1017 | struct perf_cpu_context *cpuctx; |
8a49542c PZ |
1018 | /* |
1019 | * We can have double detach due to exit/hot-unplug + close. | |
1020 | */ | |
1021 | if (!(event->attach_state & PERF_ATTACH_CONTEXT)) | |
a63eaf34 | 1022 | return; |
8a49542c PZ |
1023 | |
1024 | event->attach_state &= ~PERF_ATTACH_CONTEXT; | |
1025 | ||
68cacd29 | 1026 | if (is_cgroup_event(event)) { |
e5d1367f | 1027 | ctx->nr_cgroups--; |
68cacd29 SE |
1028 | cpuctx = __get_cpu_context(ctx); |
1029 | /* | |
1030 | * if there are no more cgroup events | |
1031 | * then cler cgrp to avoid stale pointer | |
1032 | * in update_cgrp_time_from_cpuctx() | |
1033 | */ | |
1034 | if (!ctx->nr_cgroups) | |
1035 | cpuctx->cgrp = NULL; | |
1036 | } | |
e5d1367f | 1037 | |
d010b332 SE |
1038 | if (has_branch_stack(event)) |
1039 | ctx->nr_branch_stack--; | |
1040 | ||
cdd6c482 IM |
1041 | ctx->nr_events--; |
1042 | if (event->attr.inherit_stat) | |
bfbd3381 | 1043 | ctx->nr_stat--; |
8bc20959 | 1044 | |
cdd6c482 | 1045 | list_del_rcu(&event->event_entry); |
04289bb9 | 1046 | |
8a49542c PZ |
1047 | if (event->group_leader == event) |
1048 | list_del_init(&event->group_entry); | |
5c148194 | 1049 | |
96c21a46 | 1050 | update_group_times(event); |
b2e74a26 SE |
1051 | |
1052 | /* | |
1053 | * If event was in error state, then keep it | |
1054 | * that way, otherwise bogus counts will be | |
1055 | * returned on read(). The only way to get out | |
1056 | * of error state is by explicit re-enabling | |
1057 | * of the event | |
1058 | */ | |
1059 | if (event->state > PERF_EVENT_STATE_OFF) | |
1060 | event->state = PERF_EVENT_STATE_OFF; | |
050735b0 PZ |
1061 | } |
1062 | ||
8a49542c | 1063 | static void perf_group_detach(struct perf_event *event) |
050735b0 PZ |
1064 | { |
1065 | struct perf_event *sibling, *tmp; | |
8a49542c PZ |
1066 | struct list_head *list = NULL; |
1067 | ||
1068 | /* | |
1069 | * We can have double detach due to exit/hot-unplug + close. | |
1070 | */ | |
1071 | if (!(event->attach_state & PERF_ATTACH_GROUP)) | |
1072 | return; | |
1073 | ||
1074 | event->attach_state &= ~PERF_ATTACH_GROUP; | |
1075 | ||
1076 | /* | |
1077 | * If this is a sibling, remove it from its group. | |
1078 | */ | |
1079 | if (event->group_leader != event) { | |
1080 | list_del_init(&event->group_entry); | |
1081 | event->group_leader->nr_siblings--; | |
c320c7b7 | 1082 | goto out; |
8a49542c PZ |
1083 | } |
1084 | ||
1085 | if (!list_empty(&event->group_entry)) | |
1086 | list = &event->group_entry; | |
2e2af50b | 1087 | |
04289bb9 | 1088 | /* |
cdd6c482 IM |
1089 | * If this was a group event with sibling events then |
1090 | * upgrade the siblings to singleton events by adding them | |
8a49542c | 1091 | * to whatever list we are on. |
04289bb9 | 1092 | */ |
cdd6c482 | 1093 | list_for_each_entry_safe(sibling, tmp, &event->sibling_list, group_entry) { |
8a49542c PZ |
1094 | if (list) |
1095 | list_move_tail(&sibling->group_entry, list); | |
04289bb9 | 1096 | sibling->group_leader = sibling; |
d6f962b5 FW |
1097 | |
1098 | /* Inherit group flags from the previous leader */ | |
1099 | sibling->group_flags = event->group_flags; | |
04289bb9 | 1100 | } |
c320c7b7 ACM |
1101 | |
1102 | out: | |
1103 | perf_event__header_size(event->group_leader); | |
1104 | ||
1105 | list_for_each_entry(tmp, &event->group_leader->sibling_list, group_entry) | |
1106 | perf_event__header_size(tmp); | |
04289bb9 IM |
1107 | } |
1108 | ||
fa66f07a SE |
1109 | static inline int |
1110 | event_filter_match(struct perf_event *event) | |
1111 | { | |
e5d1367f SE |
1112 | return (event->cpu == -1 || event->cpu == smp_processor_id()) |
1113 | && perf_cgroup_match(event); | |
fa66f07a SE |
1114 | } |
1115 | ||
9ffcfa6f SE |
1116 | static void |
1117 | event_sched_out(struct perf_event *event, | |
3b6f9e5c | 1118 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 1119 | struct perf_event_context *ctx) |
3b6f9e5c | 1120 | { |
4158755d | 1121 | u64 tstamp = perf_event_time(event); |
fa66f07a SE |
1122 | u64 delta; |
1123 | /* | |
1124 | * An event which could not be activated because of | |
1125 | * filter mismatch still needs to have its timings | |
1126 | * maintained, otherwise bogus information is return | |
1127 | * via read() for time_enabled, time_running: | |
1128 | */ | |
1129 | if (event->state == PERF_EVENT_STATE_INACTIVE | |
1130 | && !event_filter_match(event)) { | |
e5d1367f | 1131 | delta = tstamp - event->tstamp_stopped; |
fa66f07a | 1132 | event->tstamp_running += delta; |
4158755d | 1133 | event->tstamp_stopped = tstamp; |
fa66f07a SE |
1134 | } |
1135 | ||
cdd6c482 | 1136 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
9ffcfa6f | 1137 | return; |
3b6f9e5c | 1138 | |
cdd6c482 IM |
1139 | event->state = PERF_EVENT_STATE_INACTIVE; |
1140 | if (event->pending_disable) { | |
1141 | event->pending_disable = 0; | |
1142 | event->state = PERF_EVENT_STATE_OFF; | |
970892a9 | 1143 | } |
4158755d | 1144 | event->tstamp_stopped = tstamp; |
a4eaf7f1 | 1145 | event->pmu->del(event, 0); |
cdd6c482 | 1146 | event->oncpu = -1; |
3b6f9e5c | 1147 | |
cdd6c482 | 1148 | if (!is_software_event(event)) |
3b6f9e5c PM |
1149 | cpuctx->active_oncpu--; |
1150 | ctx->nr_active--; | |
0f5a2601 PZ |
1151 | if (event->attr.freq && event->attr.sample_freq) |
1152 | ctx->nr_freq--; | |
cdd6c482 | 1153 | if (event->attr.exclusive || !cpuctx->active_oncpu) |
3b6f9e5c PM |
1154 | cpuctx->exclusive = 0; |
1155 | } | |
1156 | ||
d859e29f | 1157 | static void |
cdd6c482 | 1158 | group_sched_out(struct perf_event *group_event, |
d859e29f | 1159 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 1160 | struct perf_event_context *ctx) |
d859e29f | 1161 | { |
cdd6c482 | 1162 | struct perf_event *event; |
fa66f07a | 1163 | int state = group_event->state; |
d859e29f | 1164 | |
cdd6c482 | 1165 | event_sched_out(group_event, cpuctx, ctx); |
d859e29f PM |
1166 | |
1167 | /* | |
1168 | * Schedule out siblings (if any): | |
1169 | */ | |
cdd6c482 IM |
1170 | list_for_each_entry(event, &group_event->sibling_list, group_entry) |
1171 | event_sched_out(event, cpuctx, ctx); | |
d859e29f | 1172 | |
fa66f07a | 1173 | if (state == PERF_EVENT_STATE_ACTIVE && group_event->attr.exclusive) |
d859e29f PM |
1174 | cpuctx->exclusive = 0; |
1175 | } | |
1176 | ||
0793a61d | 1177 | /* |
cdd6c482 | 1178 | * Cross CPU call to remove a performance event |
0793a61d | 1179 | * |
cdd6c482 | 1180 | * We disable the event on the hardware level first. After that we |
0793a61d TG |
1181 | * remove it from the context list. |
1182 | */ | |
fe4b04fa | 1183 | static int __perf_remove_from_context(void *info) |
0793a61d | 1184 | { |
cdd6c482 IM |
1185 | struct perf_event *event = info; |
1186 | struct perf_event_context *ctx = event->ctx; | |
108b02cf | 1187 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
0793a61d | 1188 | |
e625cce1 | 1189 | raw_spin_lock(&ctx->lock); |
cdd6c482 | 1190 | event_sched_out(event, cpuctx, ctx); |
cdd6c482 | 1191 | list_del_event(event, ctx); |
64ce3126 PZ |
1192 | if (!ctx->nr_events && cpuctx->task_ctx == ctx) { |
1193 | ctx->is_active = 0; | |
1194 | cpuctx->task_ctx = NULL; | |
1195 | } | |
e625cce1 | 1196 | raw_spin_unlock(&ctx->lock); |
fe4b04fa PZ |
1197 | |
1198 | return 0; | |
0793a61d TG |
1199 | } |
1200 | ||
1201 | ||
1202 | /* | |
cdd6c482 | 1203 | * Remove the event from a task's (or a CPU's) list of events. |
0793a61d | 1204 | * |
cdd6c482 | 1205 | * CPU events are removed with a smp call. For task events we only |
0793a61d | 1206 | * call when the task is on a CPU. |
c93f7669 | 1207 | * |
cdd6c482 IM |
1208 | * If event->ctx is a cloned context, callers must make sure that |
1209 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 PM |
1210 | * remains valid. This is OK when called from perf_release since |
1211 | * that only calls us on the top-level context, which can't be a clone. | |
cdd6c482 | 1212 | * When called from perf_event_exit_task, it's OK because the |
c93f7669 | 1213 | * context has been detached from its task. |
0793a61d | 1214 | */ |
fe4b04fa | 1215 | static void perf_remove_from_context(struct perf_event *event) |
0793a61d | 1216 | { |
cdd6c482 | 1217 | struct perf_event_context *ctx = event->ctx; |
0793a61d TG |
1218 | struct task_struct *task = ctx->task; |
1219 | ||
fe4b04fa PZ |
1220 | lockdep_assert_held(&ctx->mutex); |
1221 | ||
0793a61d TG |
1222 | if (!task) { |
1223 | /* | |
cdd6c482 | 1224 | * Per cpu events are removed via an smp call and |
af901ca1 | 1225 | * the removal is always successful. |
0793a61d | 1226 | */ |
fe4b04fa | 1227 | cpu_function_call(event->cpu, __perf_remove_from_context, event); |
0793a61d TG |
1228 | return; |
1229 | } | |
1230 | ||
1231 | retry: | |
fe4b04fa PZ |
1232 | if (!task_function_call(task, __perf_remove_from_context, event)) |
1233 | return; | |
0793a61d | 1234 | |
e625cce1 | 1235 | raw_spin_lock_irq(&ctx->lock); |
0793a61d | 1236 | /* |
fe4b04fa PZ |
1237 | * If we failed to find a running task, but find the context active now |
1238 | * that we've acquired the ctx->lock, retry. | |
0793a61d | 1239 | */ |
fe4b04fa | 1240 | if (ctx->is_active) { |
e625cce1 | 1241 | raw_spin_unlock_irq(&ctx->lock); |
0793a61d TG |
1242 | goto retry; |
1243 | } | |
1244 | ||
1245 | /* | |
fe4b04fa PZ |
1246 | * Since the task isn't running, its safe to remove the event, us |
1247 | * holding the ctx->lock ensures the task won't get scheduled in. | |
0793a61d | 1248 | */ |
fe4b04fa | 1249 | list_del_event(event, ctx); |
e625cce1 | 1250 | raw_spin_unlock_irq(&ctx->lock); |
0793a61d TG |
1251 | } |
1252 | ||
d859e29f | 1253 | /* |
cdd6c482 | 1254 | * Cross CPU call to disable a performance event |
d859e29f | 1255 | */ |
fe4b04fa | 1256 | static int __perf_event_disable(void *info) |
d859e29f | 1257 | { |
cdd6c482 | 1258 | struct perf_event *event = info; |
cdd6c482 | 1259 | struct perf_event_context *ctx = event->ctx; |
108b02cf | 1260 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
d859e29f PM |
1261 | |
1262 | /* | |
cdd6c482 IM |
1263 | * If this is a per-task event, need to check whether this |
1264 | * event's task is the current task on this cpu. | |
fe4b04fa PZ |
1265 | * |
1266 | * Can trigger due to concurrent perf_event_context_sched_out() | |
1267 | * flipping contexts around. | |
d859e29f | 1268 | */ |
665c2142 | 1269 | if (ctx->task && cpuctx->task_ctx != ctx) |
fe4b04fa | 1270 | return -EINVAL; |
d859e29f | 1271 | |
e625cce1 | 1272 | raw_spin_lock(&ctx->lock); |
d859e29f PM |
1273 | |
1274 | /* | |
cdd6c482 | 1275 | * If the event is on, turn it off. |
d859e29f PM |
1276 | * If it is in error state, leave it in error state. |
1277 | */ | |
cdd6c482 | 1278 | if (event->state >= PERF_EVENT_STATE_INACTIVE) { |
4af4998b | 1279 | update_context_time(ctx); |
e5d1367f | 1280 | update_cgrp_time_from_event(event); |
cdd6c482 IM |
1281 | update_group_times(event); |
1282 | if (event == event->group_leader) | |
1283 | group_sched_out(event, cpuctx, ctx); | |
d859e29f | 1284 | else |
cdd6c482 IM |
1285 | event_sched_out(event, cpuctx, ctx); |
1286 | event->state = PERF_EVENT_STATE_OFF; | |
d859e29f PM |
1287 | } |
1288 | ||
e625cce1 | 1289 | raw_spin_unlock(&ctx->lock); |
fe4b04fa PZ |
1290 | |
1291 | return 0; | |
d859e29f PM |
1292 | } |
1293 | ||
1294 | /* | |
cdd6c482 | 1295 | * Disable a event. |
c93f7669 | 1296 | * |
cdd6c482 IM |
1297 | * If event->ctx is a cloned context, callers must make sure that |
1298 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 1299 | * remains valid. This condition is satisifed when called through |
cdd6c482 IM |
1300 | * perf_event_for_each_child or perf_event_for_each because they |
1301 | * hold the top-level event's child_mutex, so any descendant that | |
1302 | * goes to exit will block in sync_child_event. | |
1303 | * When called from perf_pending_event it's OK because event->ctx | |
c93f7669 | 1304 | * is the current context on this CPU and preemption is disabled, |
cdd6c482 | 1305 | * hence we can't get into perf_event_task_sched_out for this context. |
d859e29f | 1306 | */ |
44234adc | 1307 | void perf_event_disable(struct perf_event *event) |
d859e29f | 1308 | { |
cdd6c482 | 1309 | struct perf_event_context *ctx = event->ctx; |
d859e29f PM |
1310 | struct task_struct *task = ctx->task; |
1311 | ||
1312 | if (!task) { | |
1313 | /* | |
cdd6c482 | 1314 | * Disable the event on the cpu that it's on |
d859e29f | 1315 | */ |
fe4b04fa | 1316 | cpu_function_call(event->cpu, __perf_event_disable, event); |
d859e29f PM |
1317 | return; |
1318 | } | |
1319 | ||
9ed6060d | 1320 | retry: |
fe4b04fa PZ |
1321 | if (!task_function_call(task, __perf_event_disable, event)) |
1322 | return; | |
d859e29f | 1323 | |
e625cce1 | 1324 | raw_spin_lock_irq(&ctx->lock); |
d859e29f | 1325 | /* |
cdd6c482 | 1326 | * If the event is still active, we need to retry the cross-call. |
d859e29f | 1327 | */ |
cdd6c482 | 1328 | if (event->state == PERF_EVENT_STATE_ACTIVE) { |
e625cce1 | 1329 | raw_spin_unlock_irq(&ctx->lock); |
fe4b04fa PZ |
1330 | /* |
1331 | * Reload the task pointer, it might have been changed by | |
1332 | * a concurrent perf_event_context_sched_out(). | |
1333 | */ | |
1334 | task = ctx->task; | |
d859e29f PM |
1335 | goto retry; |
1336 | } | |
1337 | ||
1338 | /* | |
1339 | * Since we have the lock this context can't be scheduled | |
1340 | * in, so we can change the state safely. | |
1341 | */ | |
cdd6c482 IM |
1342 | if (event->state == PERF_EVENT_STATE_INACTIVE) { |
1343 | update_group_times(event); | |
1344 | event->state = PERF_EVENT_STATE_OFF; | |
53cfbf59 | 1345 | } |
e625cce1 | 1346 | raw_spin_unlock_irq(&ctx->lock); |
d859e29f | 1347 | } |
dcfce4a0 | 1348 | EXPORT_SYMBOL_GPL(perf_event_disable); |
d859e29f | 1349 | |
e5d1367f SE |
1350 | static void perf_set_shadow_time(struct perf_event *event, |
1351 | struct perf_event_context *ctx, | |
1352 | u64 tstamp) | |
1353 | { | |
1354 | /* | |
1355 | * use the correct time source for the time snapshot | |
1356 | * | |
1357 | * We could get by without this by leveraging the | |
1358 | * fact that to get to this function, the caller | |
1359 | * has most likely already called update_context_time() | |
1360 | * and update_cgrp_time_xx() and thus both timestamp | |
1361 | * are identical (or very close). Given that tstamp is, | |
1362 | * already adjusted for cgroup, we could say that: | |
1363 | * tstamp - ctx->timestamp | |
1364 | * is equivalent to | |
1365 | * tstamp - cgrp->timestamp. | |
1366 | * | |
1367 | * Then, in perf_output_read(), the calculation would | |
1368 | * work with no changes because: | |
1369 | * - event is guaranteed scheduled in | |
1370 | * - no scheduled out in between | |
1371 | * - thus the timestamp would be the same | |
1372 | * | |
1373 | * But this is a bit hairy. | |
1374 | * | |
1375 | * So instead, we have an explicit cgroup call to remain | |
1376 | * within the time time source all along. We believe it | |
1377 | * is cleaner and simpler to understand. | |
1378 | */ | |
1379 | if (is_cgroup_event(event)) | |
1380 | perf_cgroup_set_shadow_time(event, tstamp); | |
1381 | else | |
1382 | event->shadow_ctx_time = tstamp - ctx->timestamp; | |
1383 | } | |
1384 | ||
4fe757dd PZ |
1385 | #define MAX_INTERRUPTS (~0ULL) |
1386 | ||
1387 | static void perf_log_throttle(struct perf_event *event, int enable); | |
1388 | ||
235c7fc7 | 1389 | static int |
9ffcfa6f | 1390 | event_sched_in(struct perf_event *event, |
235c7fc7 | 1391 | struct perf_cpu_context *cpuctx, |
6e37738a | 1392 | struct perf_event_context *ctx) |
235c7fc7 | 1393 | { |
4158755d SE |
1394 | u64 tstamp = perf_event_time(event); |
1395 | ||
cdd6c482 | 1396 | if (event->state <= PERF_EVENT_STATE_OFF) |
235c7fc7 IM |
1397 | return 0; |
1398 | ||
cdd6c482 | 1399 | event->state = PERF_EVENT_STATE_ACTIVE; |
6e37738a | 1400 | event->oncpu = smp_processor_id(); |
4fe757dd PZ |
1401 | |
1402 | /* | |
1403 | * Unthrottle events, since we scheduled we might have missed several | |
1404 | * ticks already, also for a heavily scheduling task there is little | |
1405 | * guarantee it'll get a tick in a timely manner. | |
1406 | */ | |
1407 | if (unlikely(event->hw.interrupts == MAX_INTERRUPTS)) { | |
1408 | perf_log_throttle(event, 1); | |
1409 | event->hw.interrupts = 0; | |
1410 | } | |
1411 | ||
235c7fc7 IM |
1412 | /* |
1413 | * The new state must be visible before we turn it on in the hardware: | |
1414 | */ | |
1415 | smp_wmb(); | |
1416 | ||
a4eaf7f1 | 1417 | if (event->pmu->add(event, PERF_EF_START)) { |
cdd6c482 IM |
1418 | event->state = PERF_EVENT_STATE_INACTIVE; |
1419 | event->oncpu = -1; | |
235c7fc7 IM |
1420 | return -EAGAIN; |
1421 | } | |
1422 | ||
4158755d | 1423 | event->tstamp_running += tstamp - event->tstamp_stopped; |
9ffcfa6f | 1424 | |
e5d1367f | 1425 | perf_set_shadow_time(event, ctx, tstamp); |
eed01528 | 1426 | |
cdd6c482 | 1427 | if (!is_software_event(event)) |
3b6f9e5c | 1428 | cpuctx->active_oncpu++; |
235c7fc7 | 1429 | ctx->nr_active++; |
0f5a2601 PZ |
1430 | if (event->attr.freq && event->attr.sample_freq) |
1431 | ctx->nr_freq++; | |
235c7fc7 | 1432 | |
cdd6c482 | 1433 | if (event->attr.exclusive) |
3b6f9e5c PM |
1434 | cpuctx->exclusive = 1; |
1435 | ||
235c7fc7 IM |
1436 | return 0; |
1437 | } | |
1438 | ||
6751b71e | 1439 | static int |
cdd6c482 | 1440 | group_sched_in(struct perf_event *group_event, |
6751b71e | 1441 | struct perf_cpu_context *cpuctx, |
6e37738a | 1442 | struct perf_event_context *ctx) |
6751b71e | 1443 | { |
6bde9b6c | 1444 | struct perf_event *event, *partial_group = NULL; |
51b0fe39 | 1445 | struct pmu *pmu = group_event->pmu; |
d7842da4 SE |
1446 | u64 now = ctx->time; |
1447 | bool simulate = false; | |
6751b71e | 1448 | |
cdd6c482 | 1449 | if (group_event->state == PERF_EVENT_STATE_OFF) |
6751b71e PM |
1450 | return 0; |
1451 | ||
ad5133b7 | 1452 | pmu->start_txn(pmu); |
6bde9b6c | 1453 | |
9ffcfa6f | 1454 | if (event_sched_in(group_event, cpuctx, ctx)) { |
ad5133b7 | 1455 | pmu->cancel_txn(pmu); |
6751b71e | 1456 | return -EAGAIN; |
90151c35 | 1457 | } |
6751b71e PM |
1458 | |
1459 | /* | |
1460 | * Schedule in siblings as one group (if any): | |
1461 | */ | |
cdd6c482 | 1462 | list_for_each_entry(event, &group_event->sibling_list, group_entry) { |
9ffcfa6f | 1463 | if (event_sched_in(event, cpuctx, ctx)) { |
cdd6c482 | 1464 | partial_group = event; |
6751b71e PM |
1465 | goto group_error; |
1466 | } | |
1467 | } | |
1468 | ||
9ffcfa6f | 1469 | if (!pmu->commit_txn(pmu)) |
6e85158c | 1470 | return 0; |
9ffcfa6f | 1471 | |
6751b71e PM |
1472 | group_error: |
1473 | /* | |
1474 | * Groups can be scheduled in as one unit only, so undo any | |
1475 | * partial group before returning: | |
d7842da4 SE |
1476 | * The events up to the failed event are scheduled out normally, |
1477 | * tstamp_stopped will be updated. | |
1478 | * | |
1479 | * The failed events and the remaining siblings need to have | |
1480 | * their timings updated as if they had gone thru event_sched_in() | |
1481 | * and event_sched_out(). This is required to get consistent timings | |
1482 | * across the group. This also takes care of the case where the group | |
1483 | * could never be scheduled by ensuring tstamp_stopped is set to mark | |
1484 | * the time the event was actually stopped, such that time delta | |
1485 | * calculation in update_event_times() is correct. | |
6751b71e | 1486 | */ |
cdd6c482 IM |
1487 | list_for_each_entry(event, &group_event->sibling_list, group_entry) { |
1488 | if (event == partial_group) | |
d7842da4 SE |
1489 | simulate = true; |
1490 | ||
1491 | if (simulate) { | |
1492 | event->tstamp_running += now - event->tstamp_stopped; | |
1493 | event->tstamp_stopped = now; | |
1494 | } else { | |
1495 | event_sched_out(event, cpuctx, ctx); | |
1496 | } | |
6751b71e | 1497 | } |
9ffcfa6f | 1498 | event_sched_out(group_event, cpuctx, ctx); |
6751b71e | 1499 | |
ad5133b7 | 1500 | pmu->cancel_txn(pmu); |
90151c35 | 1501 | |
6751b71e PM |
1502 | return -EAGAIN; |
1503 | } | |
1504 | ||
3b6f9e5c | 1505 | /* |
cdd6c482 | 1506 | * Work out whether we can put this event group on the CPU now. |
3b6f9e5c | 1507 | */ |
cdd6c482 | 1508 | static int group_can_go_on(struct perf_event *event, |
3b6f9e5c PM |
1509 | struct perf_cpu_context *cpuctx, |
1510 | int can_add_hw) | |
1511 | { | |
1512 | /* | |
cdd6c482 | 1513 | * Groups consisting entirely of software events can always go on. |
3b6f9e5c | 1514 | */ |
d6f962b5 | 1515 | if (event->group_flags & PERF_GROUP_SOFTWARE) |
3b6f9e5c PM |
1516 | return 1; |
1517 | /* | |
1518 | * If an exclusive group is already on, no other hardware | |
cdd6c482 | 1519 | * events can go on. |
3b6f9e5c PM |
1520 | */ |
1521 | if (cpuctx->exclusive) | |
1522 | return 0; | |
1523 | /* | |
1524 | * If this group is exclusive and there are already | |
cdd6c482 | 1525 | * events on the CPU, it can't go on. |
3b6f9e5c | 1526 | */ |
cdd6c482 | 1527 | if (event->attr.exclusive && cpuctx->active_oncpu) |
3b6f9e5c PM |
1528 | return 0; |
1529 | /* | |
1530 | * Otherwise, try to add it if all previous groups were able | |
1531 | * to go on. | |
1532 | */ | |
1533 | return can_add_hw; | |
1534 | } | |
1535 | ||
cdd6c482 IM |
1536 | static void add_event_to_ctx(struct perf_event *event, |
1537 | struct perf_event_context *ctx) | |
53cfbf59 | 1538 | { |
4158755d SE |
1539 | u64 tstamp = perf_event_time(event); |
1540 | ||
cdd6c482 | 1541 | list_add_event(event, ctx); |
8a49542c | 1542 | perf_group_attach(event); |
4158755d SE |
1543 | event->tstamp_enabled = tstamp; |
1544 | event->tstamp_running = tstamp; | |
1545 | event->tstamp_stopped = tstamp; | |
53cfbf59 PM |
1546 | } |
1547 | ||
2c29ef0f PZ |
1548 | static void task_ctx_sched_out(struct perf_event_context *ctx); |
1549 | static void | |
1550 | ctx_sched_in(struct perf_event_context *ctx, | |
1551 | struct perf_cpu_context *cpuctx, | |
1552 | enum event_type_t event_type, | |
1553 | struct task_struct *task); | |
fe4b04fa | 1554 | |
dce5855b PZ |
1555 | static void perf_event_sched_in(struct perf_cpu_context *cpuctx, |
1556 | struct perf_event_context *ctx, | |
1557 | struct task_struct *task) | |
1558 | { | |
1559 | cpu_ctx_sched_in(cpuctx, EVENT_PINNED, task); | |
1560 | if (ctx) | |
1561 | ctx_sched_in(ctx, cpuctx, EVENT_PINNED, task); | |
1562 | cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE, task); | |
1563 | if (ctx) | |
1564 | ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE, task); | |
1565 | } | |
1566 | ||
0793a61d | 1567 | /* |
cdd6c482 | 1568 | * Cross CPU call to install and enable a performance event |
682076ae PZ |
1569 | * |
1570 | * Must be called with ctx->mutex held | |
0793a61d | 1571 | */ |
fe4b04fa | 1572 | static int __perf_install_in_context(void *info) |
0793a61d | 1573 | { |
cdd6c482 IM |
1574 | struct perf_event *event = info; |
1575 | struct perf_event_context *ctx = event->ctx; | |
108b02cf | 1576 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
2c29ef0f PZ |
1577 | struct perf_event_context *task_ctx = cpuctx->task_ctx; |
1578 | struct task_struct *task = current; | |
1579 | ||
b58f6b0d | 1580 | perf_ctx_lock(cpuctx, task_ctx); |
2c29ef0f | 1581 | perf_pmu_disable(cpuctx->ctx.pmu); |
0793a61d TG |
1582 | |
1583 | /* | |
2c29ef0f | 1584 | * If there was an active task_ctx schedule it out. |
0793a61d | 1585 | */ |
b58f6b0d | 1586 | if (task_ctx) |
2c29ef0f | 1587 | task_ctx_sched_out(task_ctx); |
b58f6b0d PZ |
1588 | |
1589 | /* | |
1590 | * If the context we're installing events in is not the | |
1591 | * active task_ctx, flip them. | |
1592 | */ | |
1593 | if (ctx->task && task_ctx != ctx) { | |
1594 | if (task_ctx) | |
1595 | raw_spin_unlock(&task_ctx->lock); | |
1596 | raw_spin_lock(&ctx->lock); | |
1597 | task_ctx = ctx; | |
1598 | } | |
1599 | ||
1600 | if (task_ctx) { | |
1601 | cpuctx->task_ctx = task_ctx; | |
2c29ef0f PZ |
1602 | task = task_ctx->task; |
1603 | } | |
b58f6b0d | 1604 | |
2c29ef0f | 1605 | cpu_ctx_sched_out(cpuctx, EVENT_ALL); |
0793a61d | 1606 | |
4af4998b | 1607 | update_context_time(ctx); |
e5d1367f SE |
1608 | /* |
1609 | * update cgrp time only if current cgrp | |
1610 | * matches event->cgrp. Must be done before | |
1611 | * calling add_event_to_ctx() | |
1612 | */ | |
1613 | update_cgrp_time_from_event(event); | |
0793a61d | 1614 | |
cdd6c482 | 1615 | add_event_to_ctx(event, ctx); |
0793a61d | 1616 | |
d859e29f | 1617 | /* |
2c29ef0f | 1618 | * Schedule everything back in |
d859e29f | 1619 | */ |
dce5855b | 1620 | perf_event_sched_in(cpuctx, task_ctx, task); |
2c29ef0f PZ |
1621 | |
1622 | perf_pmu_enable(cpuctx->ctx.pmu); | |
1623 | perf_ctx_unlock(cpuctx, task_ctx); | |
fe4b04fa PZ |
1624 | |
1625 | return 0; | |
0793a61d TG |
1626 | } |
1627 | ||
1628 | /* | |
cdd6c482 | 1629 | * Attach a performance event to a context |
0793a61d | 1630 | * |
cdd6c482 IM |
1631 | * First we add the event to the list with the hardware enable bit |
1632 | * in event->hw_config cleared. | |
0793a61d | 1633 | * |
cdd6c482 | 1634 | * If the event is attached to a task which is on a CPU we use a smp |
0793a61d TG |
1635 | * call to enable it in the task context. The task might have been |
1636 | * scheduled away, but we check this in the smp call again. | |
1637 | */ | |
1638 | static void | |
cdd6c482 IM |
1639 | perf_install_in_context(struct perf_event_context *ctx, |
1640 | struct perf_event *event, | |
0793a61d TG |
1641 | int cpu) |
1642 | { | |
1643 | struct task_struct *task = ctx->task; | |
1644 | ||
fe4b04fa PZ |
1645 | lockdep_assert_held(&ctx->mutex); |
1646 | ||
c3f00c70 PZ |
1647 | event->ctx = ctx; |
1648 | ||
0793a61d TG |
1649 | if (!task) { |
1650 | /* | |
cdd6c482 | 1651 | * Per cpu events are installed via an smp call and |
af901ca1 | 1652 | * the install is always successful. |
0793a61d | 1653 | */ |
fe4b04fa | 1654 | cpu_function_call(cpu, __perf_install_in_context, event); |
0793a61d TG |
1655 | return; |
1656 | } | |
1657 | ||
0793a61d | 1658 | retry: |
fe4b04fa PZ |
1659 | if (!task_function_call(task, __perf_install_in_context, event)) |
1660 | return; | |
0793a61d | 1661 | |
e625cce1 | 1662 | raw_spin_lock_irq(&ctx->lock); |
0793a61d | 1663 | /* |
fe4b04fa PZ |
1664 | * If we failed to find a running task, but find the context active now |
1665 | * that we've acquired the ctx->lock, retry. | |
0793a61d | 1666 | */ |
fe4b04fa | 1667 | if (ctx->is_active) { |
e625cce1 | 1668 | raw_spin_unlock_irq(&ctx->lock); |
0793a61d TG |
1669 | goto retry; |
1670 | } | |
1671 | ||
1672 | /* | |
fe4b04fa PZ |
1673 | * Since the task isn't running, its safe to add the event, us holding |
1674 | * the ctx->lock ensures the task won't get scheduled in. | |
0793a61d | 1675 | */ |
fe4b04fa | 1676 | add_event_to_ctx(event, ctx); |
e625cce1 | 1677 | raw_spin_unlock_irq(&ctx->lock); |
0793a61d TG |
1678 | } |
1679 | ||
fa289bec | 1680 | /* |
cdd6c482 | 1681 | * Put a event into inactive state and update time fields. |
fa289bec PM |
1682 | * Enabling the leader of a group effectively enables all |
1683 | * the group members that aren't explicitly disabled, so we | |
1684 | * have to update their ->tstamp_enabled also. | |
1685 | * Note: this works for group members as well as group leaders | |
1686 | * since the non-leader members' sibling_lists will be empty. | |
1687 | */ | |
1d9b482e | 1688 | static void __perf_event_mark_enabled(struct perf_event *event) |
fa289bec | 1689 | { |
cdd6c482 | 1690 | struct perf_event *sub; |
4158755d | 1691 | u64 tstamp = perf_event_time(event); |
fa289bec | 1692 | |
cdd6c482 | 1693 | event->state = PERF_EVENT_STATE_INACTIVE; |
4158755d | 1694 | event->tstamp_enabled = tstamp - event->total_time_enabled; |
9ed6060d | 1695 | list_for_each_entry(sub, &event->sibling_list, group_entry) { |
4158755d SE |
1696 | if (sub->state >= PERF_EVENT_STATE_INACTIVE) |
1697 | sub->tstamp_enabled = tstamp - sub->total_time_enabled; | |
9ed6060d | 1698 | } |
fa289bec PM |
1699 | } |
1700 | ||
d859e29f | 1701 | /* |
cdd6c482 | 1702 | * Cross CPU call to enable a performance event |
d859e29f | 1703 | */ |
fe4b04fa | 1704 | static int __perf_event_enable(void *info) |
04289bb9 | 1705 | { |
cdd6c482 | 1706 | struct perf_event *event = info; |
cdd6c482 IM |
1707 | struct perf_event_context *ctx = event->ctx; |
1708 | struct perf_event *leader = event->group_leader; | |
108b02cf | 1709 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
d859e29f | 1710 | int err; |
04289bb9 | 1711 | |
fe4b04fa PZ |
1712 | if (WARN_ON_ONCE(!ctx->is_active)) |
1713 | return -EINVAL; | |
3cbed429 | 1714 | |
e625cce1 | 1715 | raw_spin_lock(&ctx->lock); |
4af4998b | 1716 | update_context_time(ctx); |
d859e29f | 1717 | |
cdd6c482 | 1718 | if (event->state >= PERF_EVENT_STATE_INACTIVE) |
d859e29f | 1719 | goto unlock; |
e5d1367f SE |
1720 | |
1721 | /* | |
1722 | * set current task's cgroup time reference point | |
1723 | */ | |
3f7cce3c | 1724 | perf_cgroup_set_timestamp(current, ctx); |
e5d1367f | 1725 | |
1d9b482e | 1726 | __perf_event_mark_enabled(event); |
04289bb9 | 1727 | |
e5d1367f SE |
1728 | if (!event_filter_match(event)) { |
1729 | if (is_cgroup_event(event)) | |
1730 | perf_cgroup_defer_enabled(event); | |
f4c4176f | 1731 | goto unlock; |
e5d1367f | 1732 | } |
f4c4176f | 1733 | |
04289bb9 | 1734 | /* |
cdd6c482 | 1735 | * If the event is in a group and isn't the group leader, |
d859e29f | 1736 | * then don't put it on unless the group is on. |
04289bb9 | 1737 | */ |
cdd6c482 | 1738 | if (leader != event && leader->state != PERF_EVENT_STATE_ACTIVE) |
d859e29f | 1739 | goto unlock; |
3b6f9e5c | 1740 | |
cdd6c482 | 1741 | if (!group_can_go_on(event, cpuctx, 1)) { |
d859e29f | 1742 | err = -EEXIST; |
e758a33d | 1743 | } else { |
cdd6c482 | 1744 | if (event == leader) |
6e37738a | 1745 | err = group_sched_in(event, cpuctx, ctx); |
e758a33d | 1746 | else |
6e37738a | 1747 | err = event_sched_in(event, cpuctx, ctx); |
e758a33d | 1748 | } |
d859e29f PM |
1749 | |
1750 | if (err) { | |
1751 | /* | |
cdd6c482 | 1752 | * If this event can't go on and it's part of a |
d859e29f PM |
1753 | * group, then the whole group has to come off. |
1754 | */ | |
cdd6c482 | 1755 | if (leader != event) |
d859e29f | 1756 | group_sched_out(leader, cpuctx, ctx); |
0d48696f | 1757 | if (leader->attr.pinned) { |
53cfbf59 | 1758 | update_group_times(leader); |
cdd6c482 | 1759 | leader->state = PERF_EVENT_STATE_ERROR; |
53cfbf59 | 1760 | } |
d859e29f PM |
1761 | } |
1762 | ||
9ed6060d | 1763 | unlock: |
e625cce1 | 1764 | raw_spin_unlock(&ctx->lock); |
fe4b04fa PZ |
1765 | |
1766 | return 0; | |
d859e29f PM |
1767 | } |
1768 | ||
1769 | /* | |
cdd6c482 | 1770 | * Enable a event. |
c93f7669 | 1771 | * |
cdd6c482 IM |
1772 | * If event->ctx is a cloned context, callers must make sure that |
1773 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 1774 | * remains valid. This condition is satisfied when called through |
cdd6c482 IM |
1775 | * perf_event_for_each_child or perf_event_for_each as described |
1776 | * for perf_event_disable. | |
d859e29f | 1777 | */ |
44234adc | 1778 | void perf_event_enable(struct perf_event *event) |
d859e29f | 1779 | { |
cdd6c482 | 1780 | struct perf_event_context *ctx = event->ctx; |
d859e29f PM |
1781 | struct task_struct *task = ctx->task; |
1782 | ||
1783 | if (!task) { | |
1784 | /* | |
cdd6c482 | 1785 | * Enable the event on the cpu that it's on |
d859e29f | 1786 | */ |
fe4b04fa | 1787 | cpu_function_call(event->cpu, __perf_event_enable, event); |
d859e29f PM |
1788 | return; |
1789 | } | |
1790 | ||
e625cce1 | 1791 | raw_spin_lock_irq(&ctx->lock); |
cdd6c482 | 1792 | if (event->state >= PERF_EVENT_STATE_INACTIVE) |
d859e29f PM |
1793 | goto out; |
1794 | ||
1795 | /* | |
cdd6c482 IM |
1796 | * If the event is in error state, clear that first. |
1797 | * That way, if we see the event in error state below, we | |
d859e29f PM |
1798 | * know that it has gone back into error state, as distinct |
1799 | * from the task having been scheduled away before the | |
1800 | * cross-call arrived. | |
1801 | */ | |
cdd6c482 IM |
1802 | if (event->state == PERF_EVENT_STATE_ERROR) |
1803 | event->state = PERF_EVENT_STATE_OFF; | |
d859e29f | 1804 | |
9ed6060d | 1805 | retry: |
fe4b04fa | 1806 | if (!ctx->is_active) { |
1d9b482e | 1807 | __perf_event_mark_enabled(event); |
fe4b04fa PZ |
1808 | goto out; |
1809 | } | |
1810 | ||
e625cce1 | 1811 | raw_spin_unlock_irq(&ctx->lock); |
fe4b04fa PZ |
1812 | |
1813 | if (!task_function_call(task, __perf_event_enable, event)) | |
1814 | return; | |
d859e29f | 1815 | |
e625cce1 | 1816 | raw_spin_lock_irq(&ctx->lock); |
d859e29f PM |
1817 | |
1818 | /* | |
cdd6c482 | 1819 | * If the context is active and the event is still off, |
d859e29f PM |
1820 | * we need to retry the cross-call. |
1821 | */ | |
fe4b04fa PZ |
1822 | if (ctx->is_active && event->state == PERF_EVENT_STATE_OFF) { |
1823 | /* | |
1824 | * task could have been flipped by a concurrent | |
1825 | * perf_event_context_sched_out() | |
1826 | */ | |
1827 | task = ctx->task; | |
d859e29f | 1828 | goto retry; |
fe4b04fa | 1829 | } |
fa289bec | 1830 | |
9ed6060d | 1831 | out: |
e625cce1 | 1832 | raw_spin_unlock_irq(&ctx->lock); |
d859e29f | 1833 | } |
dcfce4a0 | 1834 | EXPORT_SYMBOL_GPL(perf_event_enable); |
d859e29f | 1835 | |
26ca5c11 | 1836 | int perf_event_refresh(struct perf_event *event, int refresh) |
79f14641 | 1837 | { |
2023b359 | 1838 | /* |
cdd6c482 | 1839 | * not supported on inherited events |
2023b359 | 1840 | */ |
2e939d1d | 1841 | if (event->attr.inherit || !is_sampling_event(event)) |
2023b359 PZ |
1842 | return -EINVAL; |
1843 | ||
cdd6c482 IM |
1844 | atomic_add(refresh, &event->event_limit); |
1845 | perf_event_enable(event); | |
2023b359 PZ |
1846 | |
1847 | return 0; | |
79f14641 | 1848 | } |
26ca5c11 | 1849 | EXPORT_SYMBOL_GPL(perf_event_refresh); |
79f14641 | 1850 | |
5b0311e1 FW |
1851 | static void ctx_sched_out(struct perf_event_context *ctx, |
1852 | struct perf_cpu_context *cpuctx, | |
1853 | enum event_type_t event_type) | |
235c7fc7 | 1854 | { |
cdd6c482 | 1855 | struct perf_event *event; |
db24d33e | 1856 | int is_active = ctx->is_active; |
235c7fc7 | 1857 | |
db24d33e | 1858 | ctx->is_active &= ~event_type; |
cdd6c482 | 1859 | if (likely(!ctx->nr_events)) |
facc4307 PZ |
1860 | return; |
1861 | ||
4af4998b | 1862 | update_context_time(ctx); |
e5d1367f | 1863 | update_cgrp_time_from_cpuctx(cpuctx); |
5b0311e1 | 1864 | if (!ctx->nr_active) |
facc4307 | 1865 | return; |
5b0311e1 | 1866 | |
075e0b00 | 1867 | perf_pmu_disable(ctx->pmu); |
db24d33e | 1868 | if ((is_active & EVENT_PINNED) && (event_type & EVENT_PINNED)) { |
889ff015 FW |
1869 | list_for_each_entry(event, &ctx->pinned_groups, group_entry) |
1870 | group_sched_out(event, cpuctx, ctx); | |
9ed6060d | 1871 | } |
889ff015 | 1872 | |
db24d33e | 1873 | if ((is_active & EVENT_FLEXIBLE) && (event_type & EVENT_FLEXIBLE)) { |
889ff015 | 1874 | list_for_each_entry(event, &ctx->flexible_groups, group_entry) |
8c9ed8e1 | 1875 | group_sched_out(event, cpuctx, ctx); |
9ed6060d | 1876 | } |
1b9a644f | 1877 | perf_pmu_enable(ctx->pmu); |
235c7fc7 IM |
1878 | } |
1879 | ||
564c2b21 PM |
1880 | /* |
1881 | * Test whether two contexts are equivalent, i.e. whether they | |
1882 | * have both been cloned from the same version of the same context | |
cdd6c482 IM |
1883 | * and they both have the same number of enabled events. |
1884 | * If the number of enabled events is the same, then the set | |
1885 | * of enabled events should be the same, because these are both | |
1886 | * inherited contexts, therefore we can't access individual events | |
564c2b21 | 1887 | * in them directly with an fd; we can only enable/disable all |
cdd6c482 | 1888 | * events via prctl, or enable/disable all events in a family |
564c2b21 PM |
1889 | * via ioctl, which will have the same effect on both contexts. |
1890 | */ | |
cdd6c482 IM |
1891 | static int context_equiv(struct perf_event_context *ctx1, |
1892 | struct perf_event_context *ctx2) | |
564c2b21 PM |
1893 | { |
1894 | return ctx1->parent_ctx && ctx1->parent_ctx == ctx2->parent_ctx | |
ad3a37de | 1895 | && ctx1->parent_gen == ctx2->parent_gen |
25346b93 | 1896 | && !ctx1->pin_count && !ctx2->pin_count; |
564c2b21 PM |
1897 | } |
1898 | ||
cdd6c482 IM |
1899 | static void __perf_event_sync_stat(struct perf_event *event, |
1900 | struct perf_event *next_event) | |
bfbd3381 PZ |
1901 | { |
1902 | u64 value; | |
1903 | ||
cdd6c482 | 1904 | if (!event->attr.inherit_stat) |
bfbd3381 PZ |
1905 | return; |
1906 | ||
1907 | /* | |
cdd6c482 | 1908 | * Update the event value, we cannot use perf_event_read() |
bfbd3381 PZ |
1909 | * because we're in the middle of a context switch and have IRQs |
1910 | * disabled, which upsets smp_call_function_single(), however | |
cdd6c482 | 1911 | * we know the event must be on the current CPU, therefore we |
bfbd3381 PZ |
1912 | * don't need to use it. |
1913 | */ | |
cdd6c482 IM |
1914 | switch (event->state) { |
1915 | case PERF_EVENT_STATE_ACTIVE: | |
3dbebf15 PZ |
1916 | event->pmu->read(event); |
1917 | /* fall-through */ | |
bfbd3381 | 1918 | |
cdd6c482 IM |
1919 | case PERF_EVENT_STATE_INACTIVE: |
1920 | update_event_times(event); | |
bfbd3381 PZ |
1921 | break; |
1922 | ||
1923 | default: | |
1924 | break; | |
1925 | } | |
1926 | ||
1927 | /* | |
cdd6c482 | 1928 | * In order to keep per-task stats reliable we need to flip the event |
bfbd3381 PZ |
1929 | * values when we flip the contexts. |
1930 | */ | |
e7850595 PZ |
1931 | value = local64_read(&next_event->count); |
1932 | value = local64_xchg(&event->count, value); | |
1933 | local64_set(&next_event->count, value); | |
bfbd3381 | 1934 | |
cdd6c482 IM |
1935 | swap(event->total_time_enabled, next_event->total_time_enabled); |
1936 | swap(event->total_time_running, next_event->total_time_running); | |
19d2e755 | 1937 | |
bfbd3381 | 1938 | /* |
19d2e755 | 1939 | * Since we swizzled the values, update the user visible data too. |
bfbd3381 | 1940 | */ |
cdd6c482 IM |
1941 | perf_event_update_userpage(event); |
1942 | perf_event_update_userpage(next_event); | |
bfbd3381 PZ |
1943 | } |
1944 | ||
1945 | #define list_next_entry(pos, member) \ | |
1946 | list_entry(pos->member.next, typeof(*pos), member) | |
1947 | ||
cdd6c482 IM |
1948 | static void perf_event_sync_stat(struct perf_event_context *ctx, |
1949 | struct perf_event_context *next_ctx) | |
bfbd3381 | 1950 | { |
cdd6c482 | 1951 | struct perf_event *event, *next_event; |
bfbd3381 PZ |
1952 | |
1953 | if (!ctx->nr_stat) | |
1954 | return; | |
1955 | ||
02ffdbc8 PZ |
1956 | update_context_time(ctx); |
1957 | ||
cdd6c482 IM |
1958 | event = list_first_entry(&ctx->event_list, |
1959 | struct perf_event, event_entry); | |
bfbd3381 | 1960 | |
cdd6c482 IM |
1961 | next_event = list_first_entry(&next_ctx->event_list, |
1962 | struct perf_event, event_entry); | |
bfbd3381 | 1963 | |
cdd6c482 IM |
1964 | while (&event->event_entry != &ctx->event_list && |
1965 | &next_event->event_entry != &next_ctx->event_list) { | |
bfbd3381 | 1966 | |
cdd6c482 | 1967 | __perf_event_sync_stat(event, next_event); |
bfbd3381 | 1968 | |
cdd6c482 IM |
1969 | event = list_next_entry(event, event_entry); |
1970 | next_event = list_next_entry(next_event, event_entry); | |
bfbd3381 PZ |
1971 | } |
1972 | } | |
1973 | ||
fe4b04fa PZ |
1974 | static void perf_event_context_sched_out(struct task_struct *task, int ctxn, |
1975 | struct task_struct *next) | |
0793a61d | 1976 | { |
8dc85d54 | 1977 | struct perf_event_context *ctx = task->perf_event_ctxp[ctxn]; |
cdd6c482 IM |
1978 | struct perf_event_context *next_ctx; |
1979 | struct perf_event_context *parent; | |
108b02cf | 1980 | struct perf_cpu_context *cpuctx; |
c93f7669 | 1981 | int do_switch = 1; |
0793a61d | 1982 | |
108b02cf PZ |
1983 | if (likely(!ctx)) |
1984 | return; | |
10989fb2 | 1985 | |
108b02cf PZ |
1986 | cpuctx = __get_cpu_context(ctx); |
1987 | if (!cpuctx->task_ctx) | |
0793a61d TG |
1988 | return; |
1989 | ||
c93f7669 PM |
1990 | rcu_read_lock(); |
1991 | parent = rcu_dereference(ctx->parent_ctx); | |
8dc85d54 | 1992 | next_ctx = next->perf_event_ctxp[ctxn]; |
c93f7669 PM |
1993 | if (parent && next_ctx && |
1994 | rcu_dereference(next_ctx->parent_ctx) == parent) { | |
1995 | /* | |
1996 | * Looks like the two contexts are clones, so we might be | |
1997 | * able to optimize the context switch. We lock both | |
1998 | * contexts and check that they are clones under the | |
1999 | * lock (including re-checking that neither has been | |
2000 | * uncloned in the meantime). It doesn't matter which | |
2001 | * order we take the locks because no other cpu could | |
2002 | * be trying to lock both of these tasks. | |
2003 | */ | |
e625cce1 TG |
2004 | raw_spin_lock(&ctx->lock); |
2005 | raw_spin_lock_nested(&next_ctx->lock, SINGLE_DEPTH_NESTING); | |
c93f7669 | 2006 | if (context_equiv(ctx, next_ctx)) { |
665c2142 PZ |
2007 | /* |
2008 | * XXX do we need a memory barrier of sorts | |
cdd6c482 | 2009 | * wrt to rcu_dereference() of perf_event_ctxp |
665c2142 | 2010 | */ |
8dc85d54 PZ |
2011 | task->perf_event_ctxp[ctxn] = next_ctx; |
2012 | next->perf_event_ctxp[ctxn] = ctx; | |
c93f7669 PM |
2013 | ctx->task = next; |
2014 | next_ctx->task = task; | |
2015 | do_switch = 0; | |
bfbd3381 | 2016 | |
cdd6c482 | 2017 | perf_event_sync_stat(ctx, next_ctx); |
c93f7669 | 2018 | } |
e625cce1 TG |
2019 | raw_spin_unlock(&next_ctx->lock); |
2020 | raw_spin_unlock(&ctx->lock); | |
564c2b21 | 2021 | } |
c93f7669 | 2022 | rcu_read_unlock(); |
564c2b21 | 2023 | |
c93f7669 | 2024 | if (do_switch) { |
facc4307 | 2025 | raw_spin_lock(&ctx->lock); |
5b0311e1 | 2026 | ctx_sched_out(ctx, cpuctx, EVENT_ALL); |
c93f7669 | 2027 | cpuctx->task_ctx = NULL; |
facc4307 | 2028 | raw_spin_unlock(&ctx->lock); |
c93f7669 | 2029 | } |
0793a61d TG |
2030 | } |
2031 | ||
8dc85d54 PZ |
2032 | #define for_each_task_context_nr(ctxn) \ |
2033 | for ((ctxn) = 0; (ctxn) < perf_nr_task_contexts; (ctxn)++) | |
2034 | ||
2035 | /* | |
2036 | * Called from scheduler to remove the events of the current task, | |
2037 | * with interrupts disabled. | |
2038 | * | |
2039 | * We stop each event and update the event value in event->count. | |
2040 | * | |
2041 | * This does not protect us against NMI, but disable() | |
2042 | * sets the disabled bit in the control field of event _before_ | |
2043 | * accessing the event control register. If a NMI hits, then it will | |
2044 | * not restart the event. | |
2045 | */ | |
ab0cce56 JO |
2046 | void __perf_event_task_sched_out(struct task_struct *task, |
2047 | struct task_struct *next) | |
8dc85d54 PZ |
2048 | { |
2049 | int ctxn; | |
2050 | ||
8dc85d54 PZ |
2051 | for_each_task_context_nr(ctxn) |
2052 | perf_event_context_sched_out(task, ctxn, next); | |
e5d1367f SE |
2053 | |
2054 | /* | |
2055 | * if cgroup events exist on this CPU, then we need | |
2056 | * to check if we have to switch out PMU state. | |
2057 | * cgroup event are system-wide mode only | |
2058 | */ | |
2059 | if (atomic_read(&__get_cpu_var(perf_cgroup_events))) | |
a8d757ef | 2060 | perf_cgroup_sched_out(task, next); |
8dc85d54 PZ |
2061 | } |
2062 | ||
04dc2dbb | 2063 | static void task_ctx_sched_out(struct perf_event_context *ctx) |
a08b159f | 2064 | { |
108b02cf | 2065 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
a08b159f | 2066 | |
a63eaf34 PM |
2067 | if (!cpuctx->task_ctx) |
2068 | return; | |
012b84da IM |
2069 | |
2070 | if (WARN_ON_ONCE(ctx != cpuctx->task_ctx)) | |
2071 | return; | |
2072 | ||
04dc2dbb | 2073 | ctx_sched_out(ctx, cpuctx, EVENT_ALL); |
a08b159f PM |
2074 | cpuctx->task_ctx = NULL; |
2075 | } | |
2076 | ||
5b0311e1 FW |
2077 | /* |
2078 | * Called with IRQs disabled | |
2079 | */ | |
2080 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, | |
2081 | enum event_type_t event_type) | |
2082 | { | |
2083 | ctx_sched_out(&cpuctx->ctx, cpuctx, event_type); | |
04289bb9 IM |
2084 | } |
2085 | ||
235c7fc7 | 2086 | static void |
5b0311e1 | 2087 | ctx_pinned_sched_in(struct perf_event_context *ctx, |
6e37738a | 2088 | struct perf_cpu_context *cpuctx) |
0793a61d | 2089 | { |
cdd6c482 | 2090 | struct perf_event *event; |
0793a61d | 2091 | |
889ff015 FW |
2092 | list_for_each_entry(event, &ctx->pinned_groups, group_entry) { |
2093 | if (event->state <= PERF_EVENT_STATE_OFF) | |
3b6f9e5c | 2094 | continue; |
5632ab12 | 2095 | if (!event_filter_match(event)) |
3b6f9e5c PM |
2096 | continue; |
2097 | ||
e5d1367f SE |
2098 | /* may need to reset tstamp_enabled */ |
2099 | if (is_cgroup_event(event)) | |
2100 | perf_cgroup_mark_enabled(event, ctx); | |
2101 | ||
8c9ed8e1 | 2102 | if (group_can_go_on(event, cpuctx, 1)) |
6e37738a | 2103 | group_sched_in(event, cpuctx, ctx); |
3b6f9e5c PM |
2104 | |
2105 | /* | |
2106 | * If this pinned group hasn't been scheduled, | |
2107 | * put it in error state. | |
2108 | */ | |
cdd6c482 IM |
2109 | if (event->state == PERF_EVENT_STATE_INACTIVE) { |
2110 | update_group_times(event); | |
2111 | event->state = PERF_EVENT_STATE_ERROR; | |
53cfbf59 | 2112 | } |
3b6f9e5c | 2113 | } |
5b0311e1 FW |
2114 | } |
2115 | ||
2116 | static void | |
2117 | ctx_flexible_sched_in(struct perf_event_context *ctx, | |
6e37738a | 2118 | struct perf_cpu_context *cpuctx) |
5b0311e1 FW |
2119 | { |
2120 | struct perf_event *event; | |
2121 | int can_add_hw = 1; | |
3b6f9e5c | 2122 | |
889ff015 FW |
2123 | list_for_each_entry(event, &ctx->flexible_groups, group_entry) { |
2124 | /* Ignore events in OFF or ERROR state */ | |
2125 | if (event->state <= PERF_EVENT_STATE_OFF) | |
3b6f9e5c | 2126 | continue; |
04289bb9 IM |
2127 | /* |
2128 | * Listen to the 'cpu' scheduling filter constraint | |
cdd6c482 | 2129 | * of events: |
04289bb9 | 2130 | */ |
5632ab12 | 2131 | if (!event_filter_match(event)) |
0793a61d TG |
2132 | continue; |
2133 | ||
e5d1367f SE |
2134 | /* may need to reset tstamp_enabled */ |
2135 | if (is_cgroup_event(event)) | |
2136 | perf_cgroup_mark_enabled(event, ctx); | |
2137 | ||
9ed6060d | 2138 | if (group_can_go_on(event, cpuctx, can_add_hw)) { |
6e37738a | 2139 | if (group_sched_in(event, cpuctx, ctx)) |
dd0e6ba2 | 2140 | can_add_hw = 0; |
9ed6060d | 2141 | } |
0793a61d | 2142 | } |
5b0311e1 FW |
2143 | } |
2144 | ||
2145 | static void | |
2146 | ctx_sched_in(struct perf_event_context *ctx, | |
2147 | struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
2148 | enum event_type_t event_type, |
2149 | struct task_struct *task) | |
5b0311e1 | 2150 | { |
e5d1367f | 2151 | u64 now; |
db24d33e | 2152 | int is_active = ctx->is_active; |
e5d1367f | 2153 | |
db24d33e | 2154 | ctx->is_active |= event_type; |
5b0311e1 | 2155 | if (likely(!ctx->nr_events)) |
facc4307 | 2156 | return; |
5b0311e1 | 2157 | |
e5d1367f SE |
2158 | now = perf_clock(); |
2159 | ctx->timestamp = now; | |
3f7cce3c | 2160 | perf_cgroup_set_timestamp(task, ctx); |
5b0311e1 FW |
2161 | /* |
2162 | * First go through the list and put on any pinned groups | |
2163 | * in order to give them the best chance of going on. | |
2164 | */ | |
db24d33e | 2165 | if (!(is_active & EVENT_PINNED) && (event_type & EVENT_PINNED)) |
6e37738a | 2166 | ctx_pinned_sched_in(ctx, cpuctx); |
5b0311e1 FW |
2167 | |
2168 | /* Then walk through the lower prio flexible groups */ | |
db24d33e | 2169 | if (!(is_active & EVENT_FLEXIBLE) && (event_type & EVENT_FLEXIBLE)) |
6e37738a | 2170 | ctx_flexible_sched_in(ctx, cpuctx); |
235c7fc7 IM |
2171 | } |
2172 | ||
329c0e01 | 2173 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, |
e5d1367f SE |
2174 | enum event_type_t event_type, |
2175 | struct task_struct *task) | |
329c0e01 FW |
2176 | { |
2177 | struct perf_event_context *ctx = &cpuctx->ctx; | |
2178 | ||
e5d1367f | 2179 | ctx_sched_in(ctx, cpuctx, event_type, task); |
329c0e01 FW |
2180 | } |
2181 | ||
e5d1367f SE |
2182 | static void perf_event_context_sched_in(struct perf_event_context *ctx, |
2183 | struct task_struct *task) | |
235c7fc7 | 2184 | { |
108b02cf | 2185 | struct perf_cpu_context *cpuctx; |
235c7fc7 | 2186 | |
108b02cf | 2187 | cpuctx = __get_cpu_context(ctx); |
329c0e01 FW |
2188 | if (cpuctx->task_ctx == ctx) |
2189 | return; | |
2190 | ||
facc4307 | 2191 | perf_ctx_lock(cpuctx, ctx); |
1b9a644f | 2192 | perf_pmu_disable(ctx->pmu); |
329c0e01 FW |
2193 | /* |
2194 | * We want to keep the following priority order: | |
2195 | * cpu pinned (that don't need to move), task pinned, | |
2196 | * cpu flexible, task flexible. | |
2197 | */ | |
2198 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
2199 | ||
1d5f003f GN |
2200 | if (ctx->nr_events) |
2201 | cpuctx->task_ctx = ctx; | |
9b33fa6b | 2202 | |
86b47c25 GN |
2203 | perf_event_sched_in(cpuctx, cpuctx->task_ctx, task); |
2204 | ||
facc4307 PZ |
2205 | perf_pmu_enable(ctx->pmu); |
2206 | perf_ctx_unlock(cpuctx, ctx); | |
2207 | ||
b5ab4cd5 PZ |
2208 | /* |
2209 | * Since these rotations are per-cpu, we need to ensure the | |
2210 | * cpu-context we got scheduled on is actually rotating. | |
2211 | */ | |
108b02cf | 2212 | perf_pmu_rotate_start(ctx->pmu); |
235c7fc7 IM |
2213 | } |
2214 | ||
d010b332 SE |
2215 | /* |
2216 | * When sampling the branck stack in system-wide, it may be necessary | |
2217 | * to flush the stack on context switch. This happens when the branch | |
2218 | * stack does not tag its entries with the pid of the current task. | |
2219 | * Otherwise it becomes impossible to associate a branch entry with a | |
2220 | * task. This ambiguity is more likely to appear when the branch stack | |
2221 | * supports priv level filtering and the user sets it to monitor only | |
2222 | * at the user level (which could be a useful measurement in system-wide | |
2223 | * mode). In that case, the risk is high of having a branch stack with | |
2224 | * branch from multiple tasks. Flushing may mean dropping the existing | |
2225 | * entries or stashing them somewhere in the PMU specific code layer. | |
2226 | * | |
2227 | * This function provides the context switch callback to the lower code | |
2228 | * layer. It is invoked ONLY when there is at least one system-wide context | |
2229 | * with at least one active event using taken branch sampling. | |
2230 | */ | |
2231 | static void perf_branch_stack_sched_in(struct task_struct *prev, | |
2232 | struct task_struct *task) | |
2233 | { | |
2234 | struct perf_cpu_context *cpuctx; | |
2235 | struct pmu *pmu; | |
2236 | unsigned long flags; | |
2237 | ||
2238 | /* no need to flush branch stack if not changing task */ | |
2239 | if (prev == task) | |
2240 | return; | |
2241 | ||
2242 | local_irq_save(flags); | |
2243 | ||
2244 | rcu_read_lock(); | |
2245 | ||
2246 | list_for_each_entry_rcu(pmu, &pmus, entry) { | |
2247 | cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); | |
2248 | ||
2249 | /* | |
2250 | * check if the context has at least one | |
2251 | * event using PERF_SAMPLE_BRANCH_STACK | |
2252 | */ | |
2253 | if (cpuctx->ctx.nr_branch_stack > 0 | |
2254 | && pmu->flush_branch_stack) { | |
2255 | ||
2256 | pmu = cpuctx->ctx.pmu; | |
2257 | ||
2258 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); | |
2259 | ||
2260 | perf_pmu_disable(pmu); | |
2261 | ||
2262 | pmu->flush_branch_stack(); | |
2263 | ||
2264 | perf_pmu_enable(pmu); | |
2265 | ||
2266 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
2267 | } | |
2268 | } | |
2269 | ||
2270 | rcu_read_unlock(); | |
2271 | ||
2272 | local_irq_restore(flags); | |
2273 | } | |
2274 | ||
8dc85d54 PZ |
2275 | /* |
2276 | * Called from scheduler to add the events of the current task | |
2277 | * with interrupts disabled. | |
2278 | * | |
2279 | * We restore the event value and then enable it. | |
2280 | * | |
2281 | * This does not protect us against NMI, but enable() | |
2282 | * sets the enabled bit in the control field of event _before_ | |
2283 | * accessing the event control register. If a NMI hits, then it will | |
2284 | * keep the event running. | |
2285 | */ | |
ab0cce56 JO |
2286 | void __perf_event_task_sched_in(struct task_struct *prev, |
2287 | struct task_struct *task) | |
8dc85d54 PZ |
2288 | { |
2289 | struct perf_event_context *ctx; | |
2290 | int ctxn; | |
2291 | ||
2292 | for_each_task_context_nr(ctxn) { | |
2293 | ctx = task->perf_event_ctxp[ctxn]; | |
2294 | if (likely(!ctx)) | |
2295 | continue; | |
2296 | ||
e5d1367f | 2297 | perf_event_context_sched_in(ctx, task); |
8dc85d54 | 2298 | } |
e5d1367f SE |
2299 | /* |
2300 | * if cgroup events exist on this CPU, then we need | |
2301 | * to check if we have to switch in PMU state. | |
2302 | * cgroup event are system-wide mode only | |
2303 | */ | |
2304 | if (atomic_read(&__get_cpu_var(perf_cgroup_events))) | |
a8d757ef | 2305 | perf_cgroup_sched_in(prev, task); |
d010b332 SE |
2306 | |
2307 | /* check for system-wide branch_stack events */ | |
2308 | if (atomic_read(&__get_cpu_var(perf_branch_stack_events))) | |
2309 | perf_branch_stack_sched_in(prev, task); | |
235c7fc7 IM |
2310 | } |
2311 | ||
abd50713 PZ |
2312 | static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count) |
2313 | { | |
2314 | u64 frequency = event->attr.sample_freq; | |
2315 | u64 sec = NSEC_PER_SEC; | |
2316 | u64 divisor, dividend; | |
2317 | ||
2318 | int count_fls, nsec_fls, frequency_fls, sec_fls; | |
2319 | ||
2320 | count_fls = fls64(count); | |
2321 | nsec_fls = fls64(nsec); | |
2322 | frequency_fls = fls64(frequency); | |
2323 | sec_fls = 30; | |
2324 | ||
2325 | /* | |
2326 | * We got @count in @nsec, with a target of sample_freq HZ | |
2327 | * the target period becomes: | |
2328 | * | |
2329 | * @count * 10^9 | |
2330 | * period = ------------------- | |
2331 | * @nsec * sample_freq | |
2332 | * | |
2333 | */ | |
2334 | ||
2335 | /* | |
2336 | * Reduce accuracy by one bit such that @a and @b converge | |
2337 | * to a similar magnitude. | |
2338 | */ | |
fe4b04fa | 2339 | #define REDUCE_FLS(a, b) \ |
abd50713 PZ |
2340 | do { \ |
2341 | if (a##_fls > b##_fls) { \ | |
2342 | a >>= 1; \ | |
2343 | a##_fls--; \ | |
2344 | } else { \ | |
2345 | b >>= 1; \ | |
2346 | b##_fls--; \ | |
2347 | } \ | |
2348 | } while (0) | |
2349 | ||
2350 | /* | |
2351 | * Reduce accuracy until either term fits in a u64, then proceed with | |
2352 | * the other, so that finally we can do a u64/u64 division. | |
2353 | */ | |
2354 | while (count_fls + sec_fls > 64 && nsec_fls + frequency_fls > 64) { | |
2355 | REDUCE_FLS(nsec, frequency); | |
2356 | REDUCE_FLS(sec, count); | |
2357 | } | |
2358 | ||
2359 | if (count_fls + sec_fls > 64) { | |
2360 | divisor = nsec * frequency; | |
2361 | ||
2362 | while (count_fls + sec_fls > 64) { | |
2363 | REDUCE_FLS(count, sec); | |
2364 | divisor >>= 1; | |
2365 | } | |
2366 | ||
2367 | dividend = count * sec; | |
2368 | } else { | |
2369 | dividend = count * sec; | |
2370 | ||
2371 | while (nsec_fls + frequency_fls > 64) { | |
2372 | REDUCE_FLS(nsec, frequency); | |
2373 | dividend >>= 1; | |
2374 | } | |
2375 | ||
2376 | divisor = nsec * frequency; | |
2377 | } | |
2378 | ||
f6ab91ad PZ |
2379 | if (!divisor) |
2380 | return dividend; | |
2381 | ||
abd50713 PZ |
2382 | return div64_u64(dividend, divisor); |
2383 | } | |
2384 | ||
e050e3f0 SE |
2385 | static DEFINE_PER_CPU(int, perf_throttled_count); |
2386 | static DEFINE_PER_CPU(u64, perf_throttled_seq); | |
2387 | ||
f39d47ff | 2388 | static void perf_adjust_period(struct perf_event *event, u64 nsec, u64 count, bool disable) |
bd2b5b12 | 2389 | { |
cdd6c482 | 2390 | struct hw_perf_event *hwc = &event->hw; |
f6ab91ad | 2391 | s64 period, sample_period; |
bd2b5b12 PZ |
2392 | s64 delta; |
2393 | ||
abd50713 | 2394 | period = perf_calculate_period(event, nsec, count); |
bd2b5b12 PZ |
2395 | |
2396 | delta = (s64)(period - hwc->sample_period); | |
2397 | delta = (delta + 7) / 8; /* low pass filter */ | |
2398 | ||
2399 | sample_period = hwc->sample_period + delta; | |
2400 | ||
2401 | if (!sample_period) | |
2402 | sample_period = 1; | |
2403 | ||
bd2b5b12 | 2404 | hwc->sample_period = sample_period; |
abd50713 | 2405 | |
e7850595 | 2406 | if (local64_read(&hwc->period_left) > 8*sample_period) { |
f39d47ff SE |
2407 | if (disable) |
2408 | event->pmu->stop(event, PERF_EF_UPDATE); | |
2409 | ||
e7850595 | 2410 | local64_set(&hwc->period_left, 0); |
f39d47ff SE |
2411 | |
2412 | if (disable) | |
2413 | event->pmu->start(event, PERF_EF_RELOAD); | |
abd50713 | 2414 | } |
bd2b5b12 PZ |
2415 | } |
2416 | ||
e050e3f0 SE |
2417 | /* |
2418 | * combine freq adjustment with unthrottling to avoid two passes over the | |
2419 | * events. At the same time, make sure, having freq events does not change | |
2420 | * the rate of unthrottling as that would introduce bias. | |
2421 | */ | |
2422 | static void perf_adjust_freq_unthr_context(struct perf_event_context *ctx, | |
2423 | int needs_unthr) | |
60db5e09 | 2424 | { |
cdd6c482 IM |
2425 | struct perf_event *event; |
2426 | struct hw_perf_event *hwc; | |
e050e3f0 | 2427 | u64 now, period = TICK_NSEC; |
abd50713 | 2428 | s64 delta; |
60db5e09 | 2429 | |
e050e3f0 SE |
2430 | /* |
2431 | * only need to iterate over all events iff: | |
2432 | * - context have events in frequency mode (needs freq adjust) | |
2433 | * - there are events to unthrottle on this cpu | |
2434 | */ | |
2435 | if (!(ctx->nr_freq || needs_unthr)) | |
0f5a2601 PZ |
2436 | return; |
2437 | ||
e050e3f0 | 2438 | raw_spin_lock(&ctx->lock); |
f39d47ff | 2439 | perf_pmu_disable(ctx->pmu); |
e050e3f0 | 2440 | |
03541f8b | 2441 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { |
cdd6c482 | 2442 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
60db5e09 PZ |
2443 | continue; |
2444 | ||
5632ab12 | 2445 | if (!event_filter_match(event)) |
5d27c23d PZ |
2446 | continue; |
2447 | ||
cdd6c482 | 2448 | hwc = &event->hw; |
6a24ed6c | 2449 | |
e050e3f0 SE |
2450 | if (needs_unthr && hwc->interrupts == MAX_INTERRUPTS) { |
2451 | hwc->interrupts = 0; | |
cdd6c482 | 2452 | perf_log_throttle(event, 1); |
a4eaf7f1 | 2453 | event->pmu->start(event, 0); |
a78ac325 PZ |
2454 | } |
2455 | ||
cdd6c482 | 2456 | if (!event->attr.freq || !event->attr.sample_freq) |
60db5e09 PZ |
2457 | continue; |
2458 | ||
e050e3f0 SE |
2459 | /* |
2460 | * stop the event and update event->count | |
2461 | */ | |
2462 | event->pmu->stop(event, PERF_EF_UPDATE); | |
2463 | ||
e7850595 | 2464 | now = local64_read(&event->count); |
abd50713 PZ |
2465 | delta = now - hwc->freq_count_stamp; |
2466 | hwc->freq_count_stamp = now; | |
60db5e09 | 2467 | |
e050e3f0 SE |
2468 | /* |
2469 | * restart the event | |
2470 | * reload only if value has changed | |
f39d47ff SE |
2471 | * we have stopped the event so tell that |
2472 | * to perf_adjust_period() to avoid stopping it | |
2473 | * twice. | |
e050e3f0 | 2474 | */ |
abd50713 | 2475 | if (delta > 0) |
f39d47ff | 2476 | perf_adjust_period(event, period, delta, false); |
e050e3f0 SE |
2477 | |
2478 | event->pmu->start(event, delta > 0 ? PERF_EF_RELOAD : 0); | |
60db5e09 | 2479 | } |
e050e3f0 | 2480 | |
f39d47ff | 2481 | perf_pmu_enable(ctx->pmu); |
e050e3f0 | 2482 | raw_spin_unlock(&ctx->lock); |
60db5e09 PZ |
2483 | } |
2484 | ||
235c7fc7 | 2485 | /* |
cdd6c482 | 2486 | * Round-robin a context's events: |
235c7fc7 | 2487 | */ |
cdd6c482 | 2488 | static void rotate_ctx(struct perf_event_context *ctx) |
0793a61d | 2489 | { |
dddd3379 TG |
2490 | /* |
2491 | * Rotate the first entry last of non-pinned groups. Rotation might be | |
2492 | * disabled by the inheritance code. | |
2493 | */ | |
2494 | if (!ctx->rotate_disable) | |
2495 | list_rotate_left(&ctx->flexible_groups); | |
235c7fc7 IM |
2496 | } |
2497 | ||
b5ab4cd5 | 2498 | /* |
e9d2b064 PZ |
2499 | * perf_pmu_rotate_start() and perf_rotate_context() are fully serialized |
2500 | * because they're strictly cpu affine and rotate_start is called with IRQs | |
2501 | * disabled, while rotate_context is called from IRQ context. | |
b5ab4cd5 | 2502 | */ |
e9d2b064 | 2503 | static void perf_rotate_context(struct perf_cpu_context *cpuctx) |
235c7fc7 | 2504 | { |
8dc85d54 | 2505 | struct perf_event_context *ctx = NULL; |
e050e3f0 | 2506 | int rotate = 0, remove = 1; |
7fc23a53 | 2507 | |
b5ab4cd5 | 2508 | if (cpuctx->ctx.nr_events) { |
e9d2b064 | 2509 | remove = 0; |
b5ab4cd5 PZ |
2510 | if (cpuctx->ctx.nr_events != cpuctx->ctx.nr_active) |
2511 | rotate = 1; | |
2512 | } | |
235c7fc7 | 2513 | |
8dc85d54 | 2514 | ctx = cpuctx->task_ctx; |
b5ab4cd5 | 2515 | if (ctx && ctx->nr_events) { |
e9d2b064 | 2516 | remove = 0; |
b5ab4cd5 PZ |
2517 | if (ctx->nr_events != ctx->nr_active) |
2518 | rotate = 1; | |
2519 | } | |
9717e6cd | 2520 | |
e050e3f0 | 2521 | if (!rotate) |
0f5a2601 PZ |
2522 | goto done; |
2523 | ||
facc4307 | 2524 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
1b9a644f | 2525 | perf_pmu_disable(cpuctx->ctx.pmu); |
60db5e09 | 2526 | |
e050e3f0 SE |
2527 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); |
2528 | if (ctx) | |
2529 | ctx_sched_out(ctx, cpuctx, EVENT_FLEXIBLE); | |
0793a61d | 2530 | |
e050e3f0 SE |
2531 | rotate_ctx(&cpuctx->ctx); |
2532 | if (ctx) | |
2533 | rotate_ctx(ctx); | |
235c7fc7 | 2534 | |
e050e3f0 | 2535 | perf_event_sched_in(cpuctx, ctx, current); |
235c7fc7 | 2536 | |
0f5a2601 PZ |
2537 | perf_pmu_enable(cpuctx->ctx.pmu); |
2538 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
b5ab4cd5 | 2539 | done: |
e9d2b064 PZ |
2540 | if (remove) |
2541 | list_del_init(&cpuctx->rotation_list); | |
e9d2b064 PZ |
2542 | } |
2543 | ||
2544 | void perf_event_task_tick(void) | |
2545 | { | |
2546 | struct list_head *head = &__get_cpu_var(rotation_list); | |
2547 | struct perf_cpu_context *cpuctx, *tmp; | |
e050e3f0 SE |
2548 | struct perf_event_context *ctx; |
2549 | int throttled; | |
b5ab4cd5 | 2550 | |
e9d2b064 PZ |
2551 | WARN_ON(!irqs_disabled()); |
2552 | ||
e050e3f0 SE |
2553 | __this_cpu_inc(perf_throttled_seq); |
2554 | throttled = __this_cpu_xchg(perf_throttled_count, 0); | |
2555 | ||
e9d2b064 | 2556 | list_for_each_entry_safe(cpuctx, tmp, head, rotation_list) { |
e050e3f0 SE |
2557 | ctx = &cpuctx->ctx; |
2558 | perf_adjust_freq_unthr_context(ctx, throttled); | |
2559 | ||
2560 | ctx = cpuctx->task_ctx; | |
2561 | if (ctx) | |
2562 | perf_adjust_freq_unthr_context(ctx, throttled); | |
2563 | ||
e9d2b064 PZ |
2564 | if (cpuctx->jiffies_interval == 1 || |
2565 | !(jiffies % cpuctx->jiffies_interval)) | |
2566 | perf_rotate_context(cpuctx); | |
2567 | } | |
0793a61d TG |
2568 | } |
2569 | ||
889ff015 FW |
2570 | static int event_enable_on_exec(struct perf_event *event, |
2571 | struct perf_event_context *ctx) | |
2572 | { | |
2573 | if (!event->attr.enable_on_exec) | |
2574 | return 0; | |
2575 | ||
2576 | event->attr.enable_on_exec = 0; | |
2577 | if (event->state >= PERF_EVENT_STATE_INACTIVE) | |
2578 | return 0; | |
2579 | ||
1d9b482e | 2580 | __perf_event_mark_enabled(event); |
889ff015 FW |
2581 | |
2582 | return 1; | |
2583 | } | |
2584 | ||
57e7986e | 2585 | /* |
cdd6c482 | 2586 | * Enable all of a task's events that have been marked enable-on-exec. |
57e7986e PM |
2587 | * This expects task == current. |
2588 | */ | |
8dc85d54 | 2589 | static void perf_event_enable_on_exec(struct perf_event_context *ctx) |
57e7986e | 2590 | { |
cdd6c482 | 2591 | struct perf_event *event; |
57e7986e PM |
2592 | unsigned long flags; |
2593 | int enabled = 0; | |
889ff015 | 2594 | int ret; |
57e7986e PM |
2595 | |
2596 | local_irq_save(flags); | |
cdd6c482 | 2597 | if (!ctx || !ctx->nr_events) |
57e7986e PM |
2598 | goto out; |
2599 | ||
e566b76e SE |
2600 | /* |
2601 | * We must ctxsw out cgroup events to avoid conflict | |
2602 | * when invoking perf_task_event_sched_in() later on | |
2603 | * in this function. Otherwise we end up trying to | |
2604 | * ctxswin cgroup events which are already scheduled | |
2605 | * in. | |
2606 | */ | |
a8d757ef | 2607 | perf_cgroup_sched_out(current, NULL); |
57e7986e | 2608 | |
e625cce1 | 2609 | raw_spin_lock(&ctx->lock); |
04dc2dbb | 2610 | task_ctx_sched_out(ctx); |
57e7986e | 2611 | |
b79387ef | 2612 | list_for_each_entry(event, &ctx->event_list, event_entry) { |
889ff015 FW |
2613 | ret = event_enable_on_exec(event, ctx); |
2614 | if (ret) | |
2615 | enabled = 1; | |
57e7986e PM |
2616 | } |
2617 | ||
2618 | /* | |
cdd6c482 | 2619 | * Unclone this context if we enabled any event. |
57e7986e | 2620 | */ |
71a851b4 PZ |
2621 | if (enabled) |
2622 | unclone_ctx(ctx); | |
57e7986e | 2623 | |
e625cce1 | 2624 | raw_spin_unlock(&ctx->lock); |
57e7986e | 2625 | |
e566b76e SE |
2626 | /* |
2627 | * Also calls ctxswin for cgroup events, if any: | |
2628 | */ | |
e5d1367f | 2629 | perf_event_context_sched_in(ctx, ctx->task); |
9ed6060d | 2630 | out: |
57e7986e PM |
2631 | local_irq_restore(flags); |
2632 | } | |
2633 | ||
0793a61d | 2634 | /* |
cdd6c482 | 2635 | * Cross CPU call to read the hardware event |
0793a61d | 2636 | */ |
cdd6c482 | 2637 | static void __perf_event_read(void *info) |
0793a61d | 2638 | { |
cdd6c482 IM |
2639 | struct perf_event *event = info; |
2640 | struct perf_event_context *ctx = event->ctx; | |
108b02cf | 2641 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
621a01ea | 2642 | |
e1ac3614 PM |
2643 | /* |
2644 | * If this is a task context, we need to check whether it is | |
2645 | * the current task context of this cpu. If not it has been | |
2646 | * scheduled out before the smp call arrived. In that case | |
cdd6c482 IM |
2647 | * event->count would have been updated to a recent sample |
2648 | * when the event was scheduled out. | |
e1ac3614 PM |
2649 | */ |
2650 | if (ctx->task && cpuctx->task_ctx != ctx) | |
2651 | return; | |
2652 | ||
e625cce1 | 2653 | raw_spin_lock(&ctx->lock); |
e5d1367f | 2654 | if (ctx->is_active) { |
542e72fc | 2655 | update_context_time(ctx); |
e5d1367f SE |
2656 | update_cgrp_time_from_event(event); |
2657 | } | |
cdd6c482 | 2658 | update_event_times(event); |
542e72fc PZ |
2659 | if (event->state == PERF_EVENT_STATE_ACTIVE) |
2660 | event->pmu->read(event); | |
e625cce1 | 2661 | raw_spin_unlock(&ctx->lock); |
0793a61d TG |
2662 | } |
2663 | ||
b5e58793 PZ |
2664 | static inline u64 perf_event_count(struct perf_event *event) |
2665 | { | |
e7850595 | 2666 | return local64_read(&event->count) + atomic64_read(&event->child_count); |
b5e58793 PZ |
2667 | } |
2668 | ||
cdd6c482 | 2669 | static u64 perf_event_read(struct perf_event *event) |
0793a61d TG |
2670 | { |
2671 | /* | |
cdd6c482 IM |
2672 | * If event is enabled and currently active on a CPU, update the |
2673 | * value in the event structure: | |
0793a61d | 2674 | */ |
cdd6c482 IM |
2675 | if (event->state == PERF_EVENT_STATE_ACTIVE) { |
2676 | smp_call_function_single(event->oncpu, | |
2677 | __perf_event_read, event, 1); | |
2678 | } else if (event->state == PERF_EVENT_STATE_INACTIVE) { | |
2b8988c9 PZ |
2679 | struct perf_event_context *ctx = event->ctx; |
2680 | unsigned long flags; | |
2681 | ||
e625cce1 | 2682 | raw_spin_lock_irqsave(&ctx->lock, flags); |
c530ccd9 SE |
2683 | /* |
2684 | * may read while context is not active | |
2685 | * (e.g., thread is blocked), in that case | |
2686 | * we cannot update context time | |
2687 | */ | |
e5d1367f | 2688 | if (ctx->is_active) { |
c530ccd9 | 2689 | update_context_time(ctx); |
e5d1367f SE |
2690 | update_cgrp_time_from_event(event); |
2691 | } | |
cdd6c482 | 2692 | update_event_times(event); |
e625cce1 | 2693 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
0793a61d TG |
2694 | } |
2695 | ||
b5e58793 | 2696 | return perf_event_count(event); |
0793a61d TG |
2697 | } |
2698 | ||
a63eaf34 | 2699 | /* |
cdd6c482 | 2700 | * Initialize the perf_event context in a task_struct: |
a63eaf34 | 2701 | */ |
eb184479 | 2702 | static void __perf_event_init_context(struct perf_event_context *ctx) |
a63eaf34 | 2703 | { |
e625cce1 | 2704 | raw_spin_lock_init(&ctx->lock); |
a63eaf34 | 2705 | mutex_init(&ctx->mutex); |
889ff015 FW |
2706 | INIT_LIST_HEAD(&ctx->pinned_groups); |
2707 | INIT_LIST_HEAD(&ctx->flexible_groups); | |
a63eaf34 PM |
2708 | INIT_LIST_HEAD(&ctx->event_list); |
2709 | atomic_set(&ctx->refcount, 1); | |
eb184479 PZ |
2710 | } |
2711 | ||
2712 | static struct perf_event_context * | |
2713 | alloc_perf_context(struct pmu *pmu, struct task_struct *task) | |
2714 | { | |
2715 | struct perf_event_context *ctx; | |
2716 | ||
2717 | ctx = kzalloc(sizeof(struct perf_event_context), GFP_KERNEL); | |
2718 | if (!ctx) | |
2719 | return NULL; | |
2720 | ||
2721 | __perf_event_init_context(ctx); | |
2722 | if (task) { | |
2723 | ctx->task = task; | |
2724 | get_task_struct(task); | |
0793a61d | 2725 | } |
eb184479 PZ |
2726 | ctx->pmu = pmu; |
2727 | ||
2728 | return ctx; | |
a63eaf34 PM |
2729 | } |
2730 | ||
2ebd4ffb MH |
2731 | static struct task_struct * |
2732 | find_lively_task_by_vpid(pid_t vpid) | |
2733 | { | |
2734 | struct task_struct *task; | |
2735 | int err; | |
0793a61d TG |
2736 | |
2737 | rcu_read_lock(); | |
2ebd4ffb | 2738 | if (!vpid) |
0793a61d TG |
2739 | task = current; |
2740 | else | |
2ebd4ffb | 2741 | task = find_task_by_vpid(vpid); |
0793a61d TG |
2742 | if (task) |
2743 | get_task_struct(task); | |
2744 | rcu_read_unlock(); | |
2745 | ||
2746 | if (!task) | |
2747 | return ERR_PTR(-ESRCH); | |
2748 | ||
0793a61d | 2749 | /* Reuse ptrace permission checks for now. */ |
c93f7669 PM |
2750 | err = -EACCES; |
2751 | if (!ptrace_may_access(task, PTRACE_MODE_READ)) | |
2752 | goto errout; | |
2753 | ||
2ebd4ffb MH |
2754 | return task; |
2755 | errout: | |
2756 | put_task_struct(task); | |
2757 | return ERR_PTR(err); | |
2758 | ||
2759 | } | |
2760 | ||
fe4b04fa PZ |
2761 | /* |
2762 | * Returns a matching context with refcount and pincount. | |
2763 | */ | |
108b02cf | 2764 | static struct perf_event_context * |
38a81da2 | 2765 | find_get_context(struct pmu *pmu, struct task_struct *task, int cpu) |
0793a61d | 2766 | { |
cdd6c482 | 2767 | struct perf_event_context *ctx; |
22a4f650 | 2768 | struct perf_cpu_context *cpuctx; |
25346b93 | 2769 | unsigned long flags; |
8dc85d54 | 2770 | int ctxn, err; |
0793a61d | 2771 | |
22a4ec72 | 2772 | if (!task) { |
cdd6c482 | 2773 | /* Must be root to operate on a CPU event: */ |
0764771d | 2774 | if (perf_paranoid_cpu() && !capable(CAP_SYS_ADMIN)) |
0793a61d TG |
2775 | return ERR_PTR(-EACCES); |
2776 | ||
0793a61d | 2777 | /* |
cdd6c482 | 2778 | * We could be clever and allow to attach a event to an |
0793a61d TG |
2779 | * offline CPU and activate it when the CPU comes up, but |
2780 | * that's for later. | |
2781 | */ | |
f6325e30 | 2782 | if (!cpu_online(cpu)) |
0793a61d TG |
2783 | return ERR_PTR(-ENODEV); |
2784 | ||
108b02cf | 2785 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); |
0793a61d | 2786 | ctx = &cpuctx->ctx; |
c93f7669 | 2787 | get_ctx(ctx); |
fe4b04fa | 2788 | ++ctx->pin_count; |
0793a61d | 2789 | |
0793a61d TG |
2790 | return ctx; |
2791 | } | |
2792 | ||
8dc85d54 PZ |
2793 | err = -EINVAL; |
2794 | ctxn = pmu->task_ctx_nr; | |
2795 | if (ctxn < 0) | |
2796 | goto errout; | |
2797 | ||
9ed6060d | 2798 | retry: |
8dc85d54 | 2799 | ctx = perf_lock_task_context(task, ctxn, &flags); |
c93f7669 | 2800 | if (ctx) { |
71a851b4 | 2801 | unclone_ctx(ctx); |
fe4b04fa | 2802 | ++ctx->pin_count; |
e625cce1 | 2803 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
9137fb28 | 2804 | } else { |
eb184479 | 2805 | ctx = alloc_perf_context(pmu, task); |
c93f7669 PM |
2806 | err = -ENOMEM; |
2807 | if (!ctx) | |
2808 | goto errout; | |
eb184479 | 2809 | |
dbe08d82 ON |
2810 | err = 0; |
2811 | mutex_lock(&task->perf_event_mutex); | |
2812 | /* | |
2813 | * If it has already passed perf_event_exit_task(). | |
2814 | * we must see PF_EXITING, it takes this mutex too. | |
2815 | */ | |
2816 | if (task->flags & PF_EXITING) | |
2817 | err = -ESRCH; | |
2818 | else if (task->perf_event_ctxp[ctxn]) | |
2819 | err = -EAGAIN; | |
fe4b04fa | 2820 | else { |
9137fb28 | 2821 | get_ctx(ctx); |
fe4b04fa | 2822 | ++ctx->pin_count; |
dbe08d82 | 2823 | rcu_assign_pointer(task->perf_event_ctxp[ctxn], ctx); |
fe4b04fa | 2824 | } |
dbe08d82 ON |
2825 | mutex_unlock(&task->perf_event_mutex); |
2826 | ||
2827 | if (unlikely(err)) { | |
9137fb28 | 2828 | put_ctx(ctx); |
dbe08d82 ON |
2829 | |
2830 | if (err == -EAGAIN) | |
2831 | goto retry; | |
2832 | goto errout; | |
a63eaf34 PM |
2833 | } |
2834 | } | |
2835 | ||
0793a61d | 2836 | return ctx; |
c93f7669 | 2837 | |
9ed6060d | 2838 | errout: |
c93f7669 | 2839 | return ERR_PTR(err); |
0793a61d TG |
2840 | } |
2841 | ||
6fb2915d LZ |
2842 | static void perf_event_free_filter(struct perf_event *event); |
2843 | ||
cdd6c482 | 2844 | static void free_event_rcu(struct rcu_head *head) |
592903cd | 2845 | { |
cdd6c482 | 2846 | struct perf_event *event; |
592903cd | 2847 | |
cdd6c482 IM |
2848 | event = container_of(head, struct perf_event, rcu_head); |
2849 | if (event->ns) | |
2850 | put_pid_ns(event->ns); | |
6fb2915d | 2851 | perf_event_free_filter(event); |
cdd6c482 | 2852 | kfree(event); |
592903cd PZ |
2853 | } |
2854 | ||
76369139 | 2855 | static void ring_buffer_put(struct ring_buffer *rb); |
925d519a | 2856 | |
cdd6c482 | 2857 | static void free_event(struct perf_event *event) |
f1600952 | 2858 | { |
e360adbe | 2859 | irq_work_sync(&event->pending); |
925d519a | 2860 | |
cdd6c482 | 2861 | if (!event->parent) { |
82cd6def | 2862 | if (event->attach_state & PERF_ATTACH_TASK) |
c5905afb | 2863 | static_key_slow_dec_deferred(&perf_sched_events); |
3af9e859 | 2864 | if (event->attr.mmap || event->attr.mmap_data) |
cdd6c482 IM |
2865 | atomic_dec(&nr_mmap_events); |
2866 | if (event->attr.comm) | |
2867 | atomic_dec(&nr_comm_events); | |
2868 | if (event->attr.task) | |
2869 | atomic_dec(&nr_task_events); | |
927c7a9e FW |
2870 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) |
2871 | put_callchain_buffers(); | |
08309379 PZ |
2872 | if (is_cgroup_event(event)) { |
2873 | atomic_dec(&per_cpu(perf_cgroup_events, event->cpu)); | |
c5905afb | 2874 | static_key_slow_dec_deferred(&perf_sched_events); |
08309379 | 2875 | } |
d010b332 SE |
2876 | |
2877 | if (has_branch_stack(event)) { | |
2878 | static_key_slow_dec_deferred(&perf_sched_events); | |
2879 | /* is system-wide event */ | |
2880 | if (!(event->attach_state & PERF_ATTACH_TASK)) | |
2881 | atomic_dec(&per_cpu(perf_branch_stack_events, | |
2882 | event->cpu)); | |
2883 | } | |
f344011c | 2884 | } |
9ee318a7 | 2885 | |
76369139 FW |
2886 | if (event->rb) { |
2887 | ring_buffer_put(event->rb); | |
2888 | event->rb = NULL; | |
a4be7c27 PZ |
2889 | } |
2890 | ||
e5d1367f SE |
2891 | if (is_cgroup_event(event)) |
2892 | perf_detach_cgroup(event); | |
2893 | ||
cdd6c482 IM |
2894 | if (event->destroy) |
2895 | event->destroy(event); | |
e077df4f | 2896 | |
0c67b408 PZ |
2897 | if (event->ctx) |
2898 | put_ctx(event->ctx); | |
2899 | ||
cdd6c482 | 2900 | call_rcu(&event->rcu_head, free_event_rcu); |
f1600952 PZ |
2901 | } |
2902 | ||
a66a3052 | 2903 | int perf_event_release_kernel(struct perf_event *event) |
0793a61d | 2904 | { |
cdd6c482 | 2905 | struct perf_event_context *ctx = event->ctx; |
0793a61d | 2906 | |
ad3a37de | 2907 | WARN_ON_ONCE(ctx->parent_ctx); |
a0507c84 PZ |
2908 | /* |
2909 | * There are two ways this annotation is useful: | |
2910 | * | |
2911 | * 1) there is a lock recursion from perf_event_exit_task | |
2912 | * see the comment there. | |
2913 | * | |
2914 | * 2) there is a lock-inversion with mmap_sem through | |
2915 | * perf_event_read_group(), which takes faults while | |
2916 | * holding ctx->mutex, however this is called after | |
2917 | * the last filedesc died, so there is no possibility | |
2918 | * to trigger the AB-BA case. | |
2919 | */ | |
2920 | mutex_lock_nested(&ctx->mutex, SINGLE_DEPTH_NESTING); | |
050735b0 | 2921 | raw_spin_lock_irq(&ctx->lock); |
8a49542c | 2922 | perf_group_detach(event); |
050735b0 | 2923 | raw_spin_unlock_irq(&ctx->lock); |
e03a9a55 | 2924 | perf_remove_from_context(event); |
d859e29f | 2925 | mutex_unlock(&ctx->mutex); |
0793a61d | 2926 | |
cdd6c482 | 2927 | free_event(event); |
0793a61d TG |
2928 | |
2929 | return 0; | |
2930 | } | |
a66a3052 | 2931 | EXPORT_SYMBOL_GPL(perf_event_release_kernel); |
0793a61d | 2932 | |
a66a3052 PZ |
2933 | /* |
2934 | * Called when the last reference to the file is gone. | |
2935 | */ | |
2936 | static int perf_release(struct inode *inode, struct file *file) | |
fb0459d7 | 2937 | { |
a66a3052 | 2938 | struct perf_event *event = file->private_data; |
8882135b | 2939 | struct task_struct *owner; |
fb0459d7 | 2940 | |
a66a3052 | 2941 | file->private_data = NULL; |
fb0459d7 | 2942 | |
8882135b PZ |
2943 | rcu_read_lock(); |
2944 | owner = ACCESS_ONCE(event->owner); | |
2945 | /* | |
2946 | * Matches the smp_wmb() in perf_event_exit_task(). If we observe | |
2947 | * !owner it means the list deletion is complete and we can indeed | |
2948 | * free this event, otherwise we need to serialize on | |
2949 | * owner->perf_event_mutex. | |
2950 | */ | |
2951 | smp_read_barrier_depends(); | |
2952 | if (owner) { | |
2953 | /* | |
2954 | * Since delayed_put_task_struct() also drops the last | |
2955 | * task reference we can safely take a new reference | |
2956 | * while holding the rcu_read_lock(). | |
2957 | */ | |
2958 | get_task_struct(owner); | |
2959 | } | |
2960 | rcu_read_unlock(); | |
2961 | ||
2962 | if (owner) { | |
2963 | mutex_lock(&owner->perf_event_mutex); | |
2964 | /* | |
2965 | * We have to re-check the event->owner field, if it is cleared | |
2966 | * we raced with perf_event_exit_task(), acquiring the mutex | |
2967 | * ensured they're done, and we can proceed with freeing the | |
2968 | * event. | |
2969 | */ | |
2970 | if (event->owner) | |
2971 | list_del_init(&event->owner_entry); | |
2972 | mutex_unlock(&owner->perf_event_mutex); | |
2973 | put_task_struct(owner); | |
2974 | } | |
2975 | ||
a66a3052 | 2976 | return perf_event_release_kernel(event); |
fb0459d7 | 2977 | } |
fb0459d7 | 2978 | |
59ed446f | 2979 | u64 perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) |
e53c0994 | 2980 | { |
cdd6c482 | 2981 | struct perf_event *child; |
e53c0994 PZ |
2982 | u64 total = 0; |
2983 | ||
59ed446f PZ |
2984 | *enabled = 0; |
2985 | *running = 0; | |
2986 | ||
6f10581a | 2987 | mutex_lock(&event->child_mutex); |
cdd6c482 | 2988 | total += perf_event_read(event); |
59ed446f PZ |
2989 | *enabled += event->total_time_enabled + |
2990 | atomic64_read(&event->child_total_time_enabled); | |
2991 | *running += event->total_time_running + | |
2992 | atomic64_read(&event->child_total_time_running); | |
2993 | ||
2994 | list_for_each_entry(child, &event->child_list, child_list) { | |
cdd6c482 | 2995 | total += perf_event_read(child); |
59ed446f PZ |
2996 | *enabled += child->total_time_enabled; |
2997 | *running += child->total_time_running; | |
2998 | } | |
6f10581a | 2999 | mutex_unlock(&event->child_mutex); |
e53c0994 PZ |
3000 | |
3001 | return total; | |
3002 | } | |
fb0459d7 | 3003 | EXPORT_SYMBOL_GPL(perf_event_read_value); |
e53c0994 | 3004 | |
cdd6c482 | 3005 | static int perf_event_read_group(struct perf_event *event, |
3dab77fb PZ |
3006 | u64 read_format, char __user *buf) |
3007 | { | |
cdd6c482 | 3008 | struct perf_event *leader = event->group_leader, *sub; |
6f10581a PZ |
3009 | int n = 0, size = 0, ret = -EFAULT; |
3010 | struct perf_event_context *ctx = leader->ctx; | |
abf4868b | 3011 | u64 values[5]; |
59ed446f | 3012 | u64 count, enabled, running; |
abf4868b | 3013 | |
6f10581a | 3014 | mutex_lock(&ctx->mutex); |
59ed446f | 3015 | count = perf_event_read_value(leader, &enabled, &running); |
3dab77fb PZ |
3016 | |
3017 | values[n++] = 1 + leader->nr_siblings; | |
59ed446f PZ |
3018 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) |
3019 | values[n++] = enabled; | |
3020 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
3021 | values[n++] = running; | |
abf4868b PZ |
3022 | values[n++] = count; |
3023 | if (read_format & PERF_FORMAT_ID) | |
3024 | values[n++] = primary_event_id(leader); | |
3dab77fb PZ |
3025 | |
3026 | size = n * sizeof(u64); | |
3027 | ||
3028 | if (copy_to_user(buf, values, size)) | |
6f10581a | 3029 | goto unlock; |
3dab77fb | 3030 | |
6f10581a | 3031 | ret = size; |
3dab77fb | 3032 | |
65abc865 | 3033 | list_for_each_entry(sub, &leader->sibling_list, group_entry) { |
abf4868b | 3034 | n = 0; |
3dab77fb | 3035 | |
59ed446f | 3036 | values[n++] = perf_event_read_value(sub, &enabled, &running); |
abf4868b PZ |
3037 | if (read_format & PERF_FORMAT_ID) |
3038 | values[n++] = primary_event_id(sub); | |
3039 | ||
3040 | size = n * sizeof(u64); | |
3041 | ||
184d3da8 | 3042 | if (copy_to_user(buf + ret, values, size)) { |
6f10581a PZ |
3043 | ret = -EFAULT; |
3044 | goto unlock; | |
3045 | } | |
abf4868b PZ |
3046 | |
3047 | ret += size; | |
3dab77fb | 3048 | } |
6f10581a PZ |
3049 | unlock: |
3050 | mutex_unlock(&ctx->mutex); | |
3dab77fb | 3051 | |
abf4868b | 3052 | return ret; |
3dab77fb PZ |
3053 | } |
3054 | ||
cdd6c482 | 3055 | static int perf_event_read_one(struct perf_event *event, |
3dab77fb PZ |
3056 | u64 read_format, char __user *buf) |
3057 | { | |
59ed446f | 3058 | u64 enabled, running; |
3dab77fb PZ |
3059 | u64 values[4]; |
3060 | int n = 0; | |
3061 | ||
59ed446f PZ |
3062 | values[n++] = perf_event_read_value(event, &enabled, &running); |
3063 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
3064 | values[n++] = enabled; | |
3065 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
3066 | values[n++] = running; | |
3dab77fb | 3067 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 3068 | values[n++] = primary_event_id(event); |
3dab77fb PZ |
3069 | |
3070 | if (copy_to_user(buf, values, n * sizeof(u64))) | |
3071 | return -EFAULT; | |
3072 | ||
3073 | return n * sizeof(u64); | |
3074 | } | |
3075 | ||
0793a61d | 3076 | /* |
cdd6c482 | 3077 | * Read the performance event - simple non blocking version for now |
0793a61d TG |
3078 | */ |
3079 | static ssize_t | |
cdd6c482 | 3080 | perf_read_hw(struct perf_event *event, char __user *buf, size_t count) |
0793a61d | 3081 | { |
cdd6c482 | 3082 | u64 read_format = event->attr.read_format; |
3dab77fb | 3083 | int ret; |
0793a61d | 3084 | |
3b6f9e5c | 3085 | /* |
cdd6c482 | 3086 | * Return end-of-file for a read on a event that is in |
3b6f9e5c PM |
3087 | * error state (i.e. because it was pinned but it couldn't be |
3088 | * scheduled on to the CPU at some point). | |
3089 | */ | |
cdd6c482 | 3090 | if (event->state == PERF_EVENT_STATE_ERROR) |
3b6f9e5c PM |
3091 | return 0; |
3092 | ||
c320c7b7 | 3093 | if (count < event->read_size) |
3dab77fb PZ |
3094 | return -ENOSPC; |
3095 | ||
cdd6c482 | 3096 | WARN_ON_ONCE(event->ctx->parent_ctx); |
3dab77fb | 3097 | if (read_format & PERF_FORMAT_GROUP) |
cdd6c482 | 3098 | ret = perf_event_read_group(event, read_format, buf); |
3dab77fb | 3099 | else |
cdd6c482 | 3100 | ret = perf_event_read_one(event, read_format, buf); |
0793a61d | 3101 | |
3dab77fb | 3102 | return ret; |
0793a61d TG |
3103 | } |
3104 | ||
0793a61d TG |
3105 | static ssize_t |
3106 | perf_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) | |
3107 | { | |
cdd6c482 | 3108 | struct perf_event *event = file->private_data; |
0793a61d | 3109 | |
cdd6c482 | 3110 | return perf_read_hw(event, buf, count); |
0793a61d TG |
3111 | } |
3112 | ||
3113 | static unsigned int perf_poll(struct file *file, poll_table *wait) | |
3114 | { | |
cdd6c482 | 3115 | struct perf_event *event = file->private_data; |
76369139 | 3116 | struct ring_buffer *rb; |
c33a0bc4 | 3117 | unsigned int events = POLL_HUP; |
c7138f37 | 3118 | |
10c6db11 PZ |
3119 | /* |
3120 | * Race between perf_event_set_output() and perf_poll(): perf_poll() | |
3121 | * grabs the rb reference but perf_event_set_output() overrides it. | |
3122 | * Here is the timeline for two threads T1, T2: | |
3123 | * t0: T1, rb = rcu_dereference(event->rb) | |
3124 | * t1: T2, old_rb = event->rb | |
3125 | * t2: T2, event->rb = new rb | |
3126 | * t3: T2, ring_buffer_detach(old_rb) | |
3127 | * t4: T1, ring_buffer_attach(rb1) | |
3128 | * t5: T1, poll_wait(event->waitq) | |
3129 | * | |
3130 | * To avoid this problem, we grab mmap_mutex in perf_poll() | |
3131 | * thereby ensuring that the assignment of the new ring buffer | |
3132 | * and the detachment of the old buffer appear atomic to perf_poll() | |
3133 | */ | |
3134 | mutex_lock(&event->mmap_mutex); | |
3135 | ||
c7138f37 | 3136 | rcu_read_lock(); |
76369139 | 3137 | rb = rcu_dereference(event->rb); |
10c6db11 PZ |
3138 | if (rb) { |
3139 | ring_buffer_attach(event, rb); | |
76369139 | 3140 | events = atomic_xchg(&rb->poll, 0); |
10c6db11 | 3141 | } |
c7138f37 | 3142 | rcu_read_unlock(); |
0793a61d | 3143 | |
10c6db11 PZ |
3144 | mutex_unlock(&event->mmap_mutex); |
3145 | ||
cdd6c482 | 3146 | poll_wait(file, &event->waitq, wait); |
0793a61d | 3147 | |
0793a61d TG |
3148 | return events; |
3149 | } | |
3150 | ||
cdd6c482 | 3151 | static void perf_event_reset(struct perf_event *event) |
6de6a7b9 | 3152 | { |
cdd6c482 | 3153 | (void)perf_event_read(event); |
e7850595 | 3154 | local64_set(&event->count, 0); |
cdd6c482 | 3155 | perf_event_update_userpage(event); |
3df5edad PZ |
3156 | } |
3157 | ||
c93f7669 | 3158 | /* |
cdd6c482 IM |
3159 | * Holding the top-level event's child_mutex means that any |
3160 | * descendant process that has inherited this event will block | |
3161 | * in sync_child_event if it goes to exit, thus satisfying the | |
3162 | * task existence requirements of perf_event_enable/disable. | |
c93f7669 | 3163 | */ |
cdd6c482 IM |
3164 | static void perf_event_for_each_child(struct perf_event *event, |
3165 | void (*func)(struct perf_event *)) | |
3df5edad | 3166 | { |
cdd6c482 | 3167 | struct perf_event *child; |
3df5edad | 3168 | |
cdd6c482 IM |
3169 | WARN_ON_ONCE(event->ctx->parent_ctx); |
3170 | mutex_lock(&event->child_mutex); | |
3171 | func(event); | |
3172 | list_for_each_entry(child, &event->child_list, child_list) | |
3df5edad | 3173 | func(child); |
cdd6c482 | 3174 | mutex_unlock(&event->child_mutex); |
3df5edad PZ |
3175 | } |
3176 | ||
cdd6c482 IM |
3177 | static void perf_event_for_each(struct perf_event *event, |
3178 | void (*func)(struct perf_event *)) | |
3df5edad | 3179 | { |
cdd6c482 IM |
3180 | struct perf_event_context *ctx = event->ctx; |
3181 | struct perf_event *sibling; | |
3df5edad | 3182 | |
75f937f2 PZ |
3183 | WARN_ON_ONCE(ctx->parent_ctx); |
3184 | mutex_lock(&ctx->mutex); | |
cdd6c482 | 3185 | event = event->group_leader; |
75f937f2 | 3186 | |
cdd6c482 | 3187 | perf_event_for_each_child(event, func); |
cdd6c482 | 3188 | list_for_each_entry(sibling, &event->sibling_list, group_entry) |
724b6daa | 3189 | perf_event_for_each_child(sibling, func); |
75f937f2 | 3190 | mutex_unlock(&ctx->mutex); |
6de6a7b9 PZ |
3191 | } |
3192 | ||
cdd6c482 | 3193 | static int perf_event_period(struct perf_event *event, u64 __user *arg) |
08247e31 | 3194 | { |
cdd6c482 | 3195 | struct perf_event_context *ctx = event->ctx; |
08247e31 PZ |
3196 | int ret = 0; |
3197 | u64 value; | |
3198 | ||
6c7e550f | 3199 | if (!is_sampling_event(event)) |
08247e31 PZ |
3200 | return -EINVAL; |
3201 | ||
ad0cf347 | 3202 | if (copy_from_user(&value, arg, sizeof(value))) |
08247e31 PZ |
3203 | return -EFAULT; |
3204 | ||
3205 | if (!value) | |
3206 | return -EINVAL; | |
3207 | ||
e625cce1 | 3208 | raw_spin_lock_irq(&ctx->lock); |
cdd6c482 IM |
3209 | if (event->attr.freq) { |
3210 | if (value > sysctl_perf_event_sample_rate) { | |
08247e31 PZ |
3211 | ret = -EINVAL; |
3212 | goto unlock; | |
3213 | } | |
3214 | ||
cdd6c482 | 3215 | event->attr.sample_freq = value; |
08247e31 | 3216 | } else { |
cdd6c482 IM |
3217 | event->attr.sample_period = value; |
3218 | event->hw.sample_period = value; | |
08247e31 PZ |
3219 | } |
3220 | unlock: | |
e625cce1 | 3221 | raw_spin_unlock_irq(&ctx->lock); |
08247e31 PZ |
3222 | |
3223 | return ret; | |
3224 | } | |
3225 | ||
ac9721f3 PZ |
3226 | static const struct file_operations perf_fops; |
3227 | ||
3228 | static struct perf_event *perf_fget_light(int fd, int *fput_needed) | |
3229 | { | |
3230 | struct file *file; | |
3231 | ||
3232 | file = fget_light(fd, fput_needed); | |
3233 | if (!file) | |
3234 | return ERR_PTR(-EBADF); | |
3235 | ||
3236 | if (file->f_op != &perf_fops) { | |
3237 | fput_light(file, *fput_needed); | |
3238 | *fput_needed = 0; | |
3239 | return ERR_PTR(-EBADF); | |
3240 | } | |
3241 | ||
3242 | return file->private_data; | |
3243 | } | |
3244 | ||
3245 | static int perf_event_set_output(struct perf_event *event, | |
3246 | struct perf_event *output_event); | |
6fb2915d | 3247 | static int perf_event_set_filter(struct perf_event *event, void __user *arg); |
a4be7c27 | 3248 | |
d859e29f PM |
3249 | static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
3250 | { | |
cdd6c482 IM |
3251 | struct perf_event *event = file->private_data; |
3252 | void (*func)(struct perf_event *); | |
3df5edad | 3253 | u32 flags = arg; |
d859e29f PM |
3254 | |
3255 | switch (cmd) { | |
cdd6c482 IM |
3256 | case PERF_EVENT_IOC_ENABLE: |
3257 | func = perf_event_enable; | |
d859e29f | 3258 | break; |
cdd6c482 IM |
3259 | case PERF_EVENT_IOC_DISABLE: |
3260 | func = perf_event_disable; | |
79f14641 | 3261 | break; |
cdd6c482 IM |
3262 | case PERF_EVENT_IOC_RESET: |
3263 | func = perf_event_reset; | |
6de6a7b9 | 3264 | break; |
3df5edad | 3265 | |
cdd6c482 IM |
3266 | case PERF_EVENT_IOC_REFRESH: |
3267 | return perf_event_refresh(event, arg); | |
08247e31 | 3268 | |
cdd6c482 IM |
3269 | case PERF_EVENT_IOC_PERIOD: |
3270 | return perf_event_period(event, (u64 __user *)arg); | |
08247e31 | 3271 | |
cdd6c482 | 3272 | case PERF_EVENT_IOC_SET_OUTPUT: |
ac9721f3 PZ |
3273 | { |
3274 | struct perf_event *output_event = NULL; | |
3275 | int fput_needed = 0; | |
3276 | int ret; | |
3277 | ||
3278 | if (arg != -1) { | |
3279 | output_event = perf_fget_light(arg, &fput_needed); | |
3280 | if (IS_ERR(output_event)) | |
3281 | return PTR_ERR(output_event); | |
3282 | } | |
3283 | ||
3284 | ret = perf_event_set_output(event, output_event); | |
3285 | if (output_event) | |
3286 | fput_light(output_event->filp, fput_needed); | |
3287 | ||
3288 | return ret; | |
3289 | } | |
a4be7c27 | 3290 | |
6fb2915d LZ |
3291 | case PERF_EVENT_IOC_SET_FILTER: |
3292 | return perf_event_set_filter(event, (void __user *)arg); | |
3293 | ||
d859e29f | 3294 | default: |
3df5edad | 3295 | return -ENOTTY; |
d859e29f | 3296 | } |
3df5edad PZ |
3297 | |
3298 | if (flags & PERF_IOC_FLAG_GROUP) | |
cdd6c482 | 3299 | perf_event_for_each(event, func); |
3df5edad | 3300 | else |
cdd6c482 | 3301 | perf_event_for_each_child(event, func); |
3df5edad PZ |
3302 | |
3303 | return 0; | |
d859e29f PM |
3304 | } |
3305 | ||
cdd6c482 | 3306 | int perf_event_task_enable(void) |
771d7cde | 3307 | { |
cdd6c482 | 3308 | struct perf_event *event; |
771d7cde | 3309 | |
cdd6c482 IM |
3310 | mutex_lock(¤t->perf_event_mutex); |
3311 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) | |
3312 | perf_event_for_each_child(event, perf_event_enable); | |
3313 | mutex_unlock(¤t->perf_event_mutex); | |
771d7cde PZ |
3314 | |
3315 | return 0; | |
3316 | } | |
3317 | ||
cdd6c482 | 3318 | int perf_event_task_disable(void) |
771d7cde | 3319 | { |
cdd6c482 | 3320 | struct perf_event *event; |
771d7cde | 3321 | |
cdd6c482 IM |
3322 | mutex_lock(¤t->perf_event_mutex); |
3323 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) | |
3324 | perf_event_for_each_child(event, perf_event_disable); | |
3325 | mutex_unlock(¤t->perf_event_mutex); | |
771d7cde PZ |
3326 | |
3327 | return 0; | |
3328 | } | |
3329 | ||
cdd6c482 | 3330 | static int perf_event_index(struct perf_event *event) |
194002b2 | 3331 | { |
a4eaf7f1 PZ |
3332 | if (event->hw.state & PERF_HES_STOPPED) |
3333 | return 0; | |
3334 | ||
cdd6c482 | 3335 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
194002b2 PZ |
3336 | return 0; |
3337 | ||
35edc2a5 | 3338 | return event->pmu->event_idx(event); |
194002b2 PZ |
3339 | } |
3340 | ||
c4794295 | 3341 | static void calc_timer_values(struct perf_event *event, |
e3f3541c | 3342 | u64 *now, |
7f310a5d EM |
3343 | u64 *enabled, |
3344 | u64 *running) | |
c4794295 | 3345 | { |
e3f3541c | 3346 | u64 ctx_time; |
c4794295 | 3347 | |
e3f3541c PZ |
3348 | *now = perf_clock(); |
3349 | ctx_time = event->shadow_ctx_time + *now; | |
c4794295 EM |
3350 | *enabled = ctx_time - event->tstamp_enabled; |
3351 | *running = ctx_time - event->tstamp_running; | |
3352 | } | |
3353 | ||
c7206205 | 3354 | void __weak arch_perf_update_userpage(struct perf_event_mmap_page *userpg, u64 now) |
e3f3541c PZ |
3355 | { |
3356 | } | |
3357 | ||
38ff667b PZ |
3358 | /* |
3359 | * Callers need to ensure there can be no nesting of this function, otherwise | |
3360 | * the seqlock logic goes bad. We can not serialize this because the arch | |
3361 | * code calls this from NMI context. | |
3362 | */ | |
cdd6c482 | 3363 | void perf_event_update_userpage(struct perf_event *event) |
37d81828 | 3364 | { |
cdd6c482 | 3365 | struct perf_event_mmap_page *userpg; |
76369139 | 3366 | struct ring_buffer *rb; |
e3f3541c | 3367 | u64 enabled, running, now; |
38ff667b PZ |
3368 | |
3369 | rcu_read_lock(); | |
0d641208 EM |
3370 | /* |
3371 | * compute total_time_enabled, total_time_running | |
3372 | * based on snapshot values taken when the event | |
3373 | * was last scheduled in. | |
3374 | * | |
3375 | * we cannot simply called update_context_time() | |
3376 | * because of locking issue as we can be called in | |
3377 | * NMI context | |
3378 | */ | |
e3f3541c | 3379 | calc_timer_values(event, &now, &enabled, &running); |
76369139 FW |
3380 | rb = rcu_dereference(event->rb); |
3381 | if (!rb) | |
38ff667b PZ |
3382 | goto unlock; |
3383 | ||
76369139 | 3384 | userpg = rb->user_page; |
37d81828 | 3385 | |
7b732a75 PZ |
3386 | /* |
3387 | * Disable preemption so as to not let the corresponding user-space | |
3388 | * spin too long if we get preempted. | |
3389 | */ | |
3390 | preempt_disable(); | |
37d81828 | 3391 | ++userpg->lock; |
92f22a38 | 3392 | barrier(); |
cdd6c482 | 3393 | userpg->index = perf_event_index(event); |
b5e58793 | 3394 | userpg->offset = perf_event_count(event); |
365a4038 | 3395 | if (userpg->index) |
e7850595 | 3396 | userpg->offset -= local64_read(&event->hw.prev_count); |
7b732a75 | 3397 | |
0d641208 | 3398 | userpg->time_enabled = enabled + |
cdd6c482 | 3399 | atomic64_read(&event->child_total_time_enabled); |
7f8b4e4e | 3400 | |
0d641208 | 3401 | userpg->time_running = running + |
cdd6c482 | 3402 | atomic64_read(&event->child_total_time_running); |
7f8b4e4e | 3403 | |
c7206205 | 3404 | arch_perf_update_userpage(userpg, now); |
e3f3541c | 3405 | |
92f22a38 | 3406 | barrier(); |
37d81828 | 3407 | ++userpg->lock; |
7b732a75 | 3408 | preempt_enable(); |
38ff667b | 3409 | unlock: |
7b732a75 | 3410 | rcu_read_unlock(); |
37d81828 PM |
3411 | } |
3412 | ||
906010b2 PZ |
3413 | static int perf_mmap_fault(struct vm_area_struct *vma, struct vm_fault *vmf) |
3414 | { | |
3415 | struct perf_event *event = vma->vm_file->private_data; | |
76369139 | 3416 | struct ring_buffer *rb; |
906010b2 PZ |
3417 | int ret = VM_FAULT_SIGBUS; |
3418 | ||
3419 | if (vmf->flags & FAULT_FLAG_MKWRITE) { | |
3420 | if (vmf->pgoff == 0) | |
3421 | ret = 0; | |
3422 | return ret; | |
3423 | } | |
3424 | ||
3425 | rcu_read_lock(); | |
76369139 FW |
3426 | rb = rcu_dereference(event->rb); |
3427 | if (!rb) | |
906010b2 PZ |
3428 | goto unlock; |
3429 | ||
3430 | if (vmf->pgoff && (vmf->flags & FAULT_FLAG_WRITE)) | |
3431 | goto unlock; | |
3432 | ||
76369139 | 3433 | vmf->page = perf_mmap_to_page(rb, vmf->pgoff); |
906010b2 PZ |
3434 | if (!vmf->page) |
3435 | goto unlock; | |
3436 | ||
3437 | get_page(vmf->page); | |
3438 | vmf->page->mapping = vma->vm_file->f_mapping; | |
3439 | vmf->page->index = vmf->pgoff; | |
3440 | ||
3441 | ret = 0; | |
3442 | unlock: | |
3443 | rcu_read_unlock(); | |
3444 | ||
3445 | return ret; | |
3446 | } | |
3447 | ||
10c6db11 PZ |
3448 | static void ring_buffer_attach(struct perf_event *event, |
3449 | struct ring_buffer *rb) | |
3450 | { | |
3451 | unsigned long flags; | |
3452 | ||
3453 | if (!list_empty(&event->rb_entry)) | |
3454 | return; | |
3455 | ||
3456 | spin_lock_irqsave(&rb->event_lock, flags); | |
3457 | if (!list_empty(&event->rb_entry)) | |
3458 | goto unlock; | |
3459 | ||
3460 | list_add(&event->rb_entry, &rb->event_list); | |
3461 | unlock: | |
3462 | spin_unlock_irqrestore(&rb->event_lock, flags); | |
3463 | } | |
3464 | ||
3465 | static void ring_buffer_detach(struct perf_event *event, | |
3466 | struct ring_buffer *rb) | |
3467 | { | |
3468 | unsigned long flags; | |
3469 | ||
3470 | if (list_empty(&event->rb_entry)) | |
3471 | return; | |
3472 | ||
3473 | spin_lock_irqsave(&rb->event_lock, flags); | |
3474 | list_del_init(&event->rb_entry); | |
3475 | wake_up_all(&event->waitq); | |
3476 | spin_unlock_irqrestore(&rb->event_lock, flags); | |
3477 | } | |
3478 | ||
3479 | static void ring_buffer_wakeup(struct perf_event *event) | |
3480 | { | |
3481 | struct ring_buffer *rb; | |
3482 | ||
3483 | rcu_read_lock(); | |
3484 | rb = rcu_dereference(event->rb); | |
44b7f4b9 WD |
3485 | if (!rb) |
3486 | goto unlock; | |
3487 | ||
3488 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) | |
10c6db11 | 3489 | wake_up_all(&event->waitq); |
44b7f4b9 WD |
3490 | |
3491 | unlock: | |
10c6db11 PZ |
3492 | rcu_read_unlock(); |
3493 | } | |
3494 | ||
76369139 | 3495 | static void rb_free_rcu(struct rcu_head *rcu_head) |
906010b2 | 3496 | { |
76369139 | 3497 | struct ring_buffer *rb; |
906010b2 | 3498 | |
76369139 FW |
3499 | rb = container_of(rcu_head, struct ring_buffer, rcu_head); |
3500 | rb_free(rb); | |
7b732a75 PZ |
3501 | } |
3502 | ||
76369139 | 3503 | static struct ring_buffer *ring_buffer_get(struct perf_event *event) |
7b732a75 | 3504 | { |
76369139 | 3505 | struct ring_buffer *rb; |
7b732a75 | 3506 | |
ac9721f3 | 3507 | rcu_read_lock(); |
76369139 FW |
3508 | rb = rcu_dereference(event->rb); |
3509 | if (rb) { | |
3510 | if (!atomic_inc_not_zero(&rb->refcount)) | |
3511 | rb = NULL; | |
ac9721f3 PZ |
3512 | } |
3513 | rcu_read_unlock(); | |
3514 | ||
76369139 | 3515 | return rb; |
ac9721f3 PZ |
3516 | } |
3517 | ||
76369139 | 3518 | static void ring_buffer_put(struct ring_buffer *rb) |
ac9721f3 | 3519 | { |
10c6db11 PZ |
3520 | struct perf_event *event, *n; |
3521 | unsigned long flags; | |
3522 | ||
76369139 | 3523 | if (!atomic_dec_and_test(&rb->refcount)) |
ac9721f3 | 3524 | return; |
7b732a75 | 3525 | |
10c6db11 PZ |
3526 | spin_lock_irqsave(&rb->event_lock, flags); |
3527 | list_for_each_entry_safe(event, n, &rb->event_list, rb_entry) { | |
3528 | list_del_init(&event->rb_entry); | |
3529 | wake_up_all(&event->waitq); | |
3530 | } | |
3531 | spin_unlock_irqrestore(&rb->event_lock, flags); | |
3532 | ||
76369139 | 3533 | call_rcu(&rb->rcu_head, rb_free_rcu); |
7b732a75 PZ |
3534 | } |
3535 | ||
3536 | static void perf_mmap_open(struct vm_area_struct *vma) | |
3537 | { | |
cdd6c482 | 3538 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 3539 | |
cdd6c482 | 3540 | atomic_inc(&event->mmap_count); |
7b732a75 PZ |
3541 | } |
3542 | ||
3543 | static void perf_mmap_close(struct vm_area_struct *vma) | |
3544 | { | |
cdd6c482 | 3545 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 3546 | |
cdd6c482 | 3547 | if (atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex)) { |
76369139 | 3548 | unsigned long size = perf_data_size(event->rb); |
ac9721f3 | 3549 | struct user_struct *user = event->mmap_user; |
76369139 | 3550 | struct ring_buffer *rb = event->rb; |
789f90fc | 3551 | |
906010b2 | 3552 | atomic_long_sub((size >> PAGE_SHIFT) + 1, &user->locked_vm); |
bc3e53f6 | 3553 | vma->vm_mm->pinned_vm -= event->mmap_locked; |
76369139 | 3554 | rcu_assign_pointer(event->rb, NULL); |
10c6db11 | 3555 | ring_buffer_detach(event, rb); |
cdd6c482 | 3556 | mutex_unlock(&event->mmap_mutex); |
ac9721f3 | 3557 | |
76369139 | 3558 | ring_buffer_put(rb); |
ac9721f3 | 3559 | free_uid(user); |
7b732a75 | 3560 | } |
37d81828 PM |
3561 | } |
3562 | ||
f0f37e2f | 3563 | static const struct vm_operations_struct perf_mmap_vmops = { |
43a21ea8 PZ |
3564 | .open = perf_mmap_open, |
3565 | .close = perf_mmap_close, | |
3566 | .fault = perf_mmap_fault, | |
3567 | .page_mkwrite = perf_mmap_fault, | |
37d81828 PM |
3568 | }; |
3569 | ||
3570 | static int perf_mmap(struct file *file, struct vm_area_struct *vma) | |
3571 | { | |
cdd6c482 | 3572 | struct perf_event *event = file->private_data; |
22a4f650 | 3573 | unsigned long user_locked, user_lock_limit; |
789f90fc | 3574 | struct user_struct *user = current_user(); |
22a4f650 | 3575 | unsigned long locked, lock_limit; |
76369139 | 3576 | struct ring_buffer *rb; |
7b732a75 PZ |
3577 | unsigned long vma_size; |
3578 | unsigned long nr_pages; | |
789f90fc | 3579 | long user_extra, extra; |
d57e34fd | 3580 | int ret = 0, flags = 0; |
37d81828 | 3581 | |
c7920614 PZ |
3582 | /* |
3583 | * Don't allow mmap() of inherited per-task counters. This would | |
3584 | * create a performance issue due to all children writing to the | |
76369139 | 3585 | * same rb. |
c7920614 PZ |
3586 | */ |
3587 | if (event->cpu == -1 && event->attr.inherit) | |
3588 | return -EINVAL; | |
3589 | ||
43a21ea8 | 3590 | if (!(vma->vm_flags & VM_SHARED)) |
37d81828 | 3591 | return -EINVAL; |
7b732a75 PZ |
3592 | |
3593 | vma_size = vma->vm_end - vma->vm_start; | |
3594 | nr_pages = (vma_size / PAGE_SIZE) - 1; | |
3595 | ||
7730d865 | 3596 | /* |
76369139 | 3597 | * If we have rb pages ensure they're a power-of-two number, so we |
7730d865 PZ |
3598 | * can do bitmasks instead of modulo. |
3599 | */ | |
3600 | if (nr_pages != 0 && !is_power_of_2(nr_pages)) | |
37d81828 PM |
3601 | return -EINVAL; |
3602 | ||
7b732a75 | 3603 | if (vma_size != PAGE_SIZE * (1 + nr_pages)) |
37d81828 PM |
3604 | return -EINVAL; |
3605 | ||
7b732a75 PZ |
3606 | if (vma->vm_pgoff != 0) |
3607 | return -EINVAL; | |
37d81828 | 3608 | |
cdd6c482 IM |
3609 | WARN_ON_ONCE(event->ctx->parent_ctx); |
3610 | mutex_lock(&event->mmap_mutex); | |
76369139 FW |
3611 | if (event->rb) { |
3612 | if (event->rb->nr_pages == nr_pages) | |
3613 | atomic_inc(&event->rb->refcount); | |
ac9721f3 | 3614 | else |
ebb3c4c4 PZ |
3615 | ret = -EINVAL; |
3616 | goto unlock; | |
3617 | } | |
3618 | ||
789f90fc | 3619 | user_extra = nr_pages + 1; |
cdd6c482 | 3620 | user_lock_limit = sysctl_perf_event_mlock >> (PAGE_SHIFT - 10); |
a3862d3f IM |
3621 | |
3622 | /* | |
3623 | * Increase the limit linearly with more CPUs: | |
3624 | */ | |
3625 | user_lock_limit *= num_online_cpus(); | |
3626 | ||
789f90fc | 3627 | user_locked = atomic_long_read(&user->locked_vm) + user_extra; |
c5078f78 | 3628 | |
789f90fc PZ |
3629 | extra = 0; |
3630 | if (user_locked > user_lock_limit) | |
3631 | extra = user_locked - user_lock_limit; | |
7b732a75 | 3632 | |
78d7d407 | 3633 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
7b732a75 | 3634 | lock_limit >>= PAGE_SHIFT; |
bc3e53f6 | 3635 | locked = vma->vm_mm->pinned_vm + extra; |
7b732a75 | 3636 | |
459ec28a IM |
3637 | if ((locked > lock_limit) && perf_paranoid_tracepoint_raw() && |
3638 | !capable(CAP_IPC_LOCK)) { | |
ebb3c4c4 PZ |
3639 | ret = -EPERM; |
3640 | goto unlock; | |
3641 | } | |
7b732a75 | 3642 | |
76369139 | 3643 | WARN_ON(event->rb); |
906010b2 | 3644 | |
d57e34fd | 3645 | if (vma->vm_flags & VM_WRITE) |
76369139 | 3646 | flags |= RING_BUFFER_WRITABLE; |
d57e34fd | 3647 | |
4ec8363d VW |
3648 | rb = rb_alloc(nr_pages, |
3649 | event->attr.watermark ? event->attr.wakeup_watermark : 0, | |
3650 | event->cpu, flags); | |
3651 | ||
76369139 | 3652 | if (!rb) { |
ac9721f3 | 3653 | ret = -ENOMEM; |
ebb3c4c4 | 3654 | goto unlock; |
ac9721f3 | 3655 | } |
76369139 | 3656 | rcu_assign_pointer(event->rb, rb); |
43a21ea8 | 3657 | |
ac9721f3 PZ |
3658 | atomic_long_add(user_extra, &user->locked_vm); |
3659 | event->mmap_locked = extra; | |
3660 | event->mmap_user = get_current_user(); | |
bc3e53f6 | 3661 | vma->vm_mm->pinned_vm += event->mmap_locked; |
ac9721f3 | 3662 | |
9a0f05cb PZ |
3663 | perf_event_update_userpage(event); |
3664 | ||
ebb3c4c4 | 3665 | unlock: |
ac9721f3 PZ |
3666 | if (!ret) |
3667 | atomic_inc(&event->mmap_count); | |
cdd6c482 | 3668 | mutex_unlock(&event->mmap_mutex); |
37d81828 | 3669 | |
37d81828 PM |
3670 | vma->vm_flags |= VM_RESERVED; |
3671 | vma->vm_ops = &perf_mmap_vmops; | |
7b732a75 PZ |
3672 | |
3673 | return ret; | |
37d81828 PM |
3674 | } |
3675 | ||
3c446b3d PZ |
3676 | static int perf_fasync(int fd, struct file *filp, int on) |
3677 | { | |
3c446b3d | 3678 | struct inode *inode = filp->f_path.dentry->d_inode; |
cdd6c482 | 3679 | struct perf_event *event = filp->private_data; |
3c446b3d PZ |
3680 | int retval; |
3681 | ||
3682 | mutex_lock(&inode->i_mutex); | |
cdd6c482 | 3683 | retval = fasync_helper(fd, filp, on, &event->fasync); |
3c446b3d PZ |
3684 | mutex_unlock(&inode->i_mutex); |
3685 | ||
3686 | if (retval < 0) | |
3687 | return retval; | |
3688 | ||
3689 | return 0; | |
3690 | } | |
3691 | ||
0793a61d | 3692 | static const struct file_operations perf_fops = { |
3326c1ce | 3693 | .llseek = no_llseek, |
0793a61d TG |
3694 | .release = perf_release, |
3695 | .read = perf_read, | |
3696 | .poll = perf_poll, | |
d859e29f PM |
3697 | .unlocked_ioctl = perf_ioctl, |
3698 | .compat_ioctl = perf_ioctl, | |
37d81828 | 3699 | .mmap = perf_mmap, |
3c446b3d | 3700 | .fasync = perf_fasync, |
0793a61d TG |
3701 | }; |
3702 | ||
925d519a | 3703 | /* |
cdd6c482 | 3704 | * Perf event wakeup |
925d519a PZ |
3705 | * |
3706 | * If there's data, ensure we set the poll() state and publish everything | |
3707 | * to user-space before waking everybody up. | |
3708 | */ | |
3709 | ||
cdd6c482 | 3710 | void perf_event_wakeup(struct perf_event *event) |
925d519a | 3711 | { |
10c6db11 | 3712 | ring_buffer_wakeup(event); |
4c9e2542 | 3713 | |
cdd6c482 IM |
3714 | if (event->pending_kill) { |
3715 | kill_fasync(&event->fasync, SIGIO, event->pending_kill); | |
3716 | event->pending_kill = 0; | |
4c9e2542 | 3717 | } |
925d519a PZ |
3718 | } |
3719 | ||
e360adbe | 3720 | static void perf_pending_event(struct irq_work *entry) |
79f14641 | 3721 | { |
cdd6c482 IM |
3722 | struct perf_event *event = container_of(entry, |
3723 | struct perf_event, pending); | |
79f14641 | 3724 | |
cdd6c482 IM |
3725 | if (event->pending_disable) { |
3726 | event->pending_disable = 0; | |
3727 | __perf_event_disable(event); | |
79f14641 PZ |
3728 | } |
3729 | ||
cdd6c482 IM |
3730 | if (event->pending_wakeup) { |
3731 | event->pending_wakeup = 0; | |
3732 | perf_event_wakeup(event); | |
79f14641 PZ |
3733 | } |
3734 | } | |
3735 | ||
39447b38 ZY |
3736 | /* |
3737 | * We assume there is only KVM supporting the callbacks. | |
3738 | * Later on, we might change it to a list if there is | |
3739 | * another virtualization implementation supporting the callbacks. | |
3740 | */ | |
3741 | struct perf_guest_info_callbacks *perf_guest_cbs; | |
3742 | ||
3743 | int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
3744 | { | |
3745 | perf_guest_cbs = cbs; | |
3746 | return 0; | |
3747 | } | |
3748 | EXPORT_SYMBOL_GPL(perf_register_guest_info_callbacks); | |
3749 | ||
3750 | int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
3751 | { | |
3752 | perf_guest_cbs = NULL; | |
3753 | return 0; | |
3754 | } | |
3755 | EXPORT_SYMBOL_GPL(perf_unregister_guest_info_callbacks); | |
3756 | ||
c980d109 ACM |
3757 | static void __perf_event_header__init_id(struct perf_event_header *header, |
3758 | struct perf_sample_data *data, | |
3759 | struct perf_event *event) | |
6844c09d ACM |
3760 | { |
3761 | u64 sample_type = event->attr.sample_type; | |
3762 | ||
3763 | data->type = sample_type; | |
3764 | header->size += event->id_header_size; | |
3765 | ||
3766 | if (sample_type & PERF_SAMPLE_TID) { | |
3767 | /* namespace issues */ | |
3768 | data->tid_entry.pid = perf_event_pid(event, current); | |
3769 | data->tid_entry.tid = perf_event_tid(event, current); | |
3770 | } | |
3771 | ||
3772 | if (sample_type & PERF_SAMPLE_TIME) | |
3773 | data->time = perf_clock(); | |
3774 | ||
3775 | if (sample_type & PERF_SAMPLE_ID) | |
3776 | data->id = primary_event_id(event); | |
3777 | ||
3778 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
3779 | data->stream_id = event->id; | |
3780 | ||
3781 | if (sample_type & PERF_SAMPLE_CPU) { | |
3782 | data->cpu_entry.cpu = raw_smp_processor_id(); | |
3783 | data->cpu_entry.reserved = 0; | |
3784 | } | |
3785 | } | |
3786 | ||
76369139 FW |
3787 | void perf_event_header__init_id(struct perf_event_header *header, |
3788 | struct perf_sample_data *data, | |
3789 | struct perf_event *event) | |
c980d109 ACM |
3790 | { |
3791 | if (event->attr.sample_id_all) | |
3792 | __perf_event_header__init_id(header, data, event); | |
3793 | } | |
3794 | ||
3795 | static void __perf_event__output_id_sample(struct perf_output_handle *handle, | |
3796 | struct perf_sample_data *data) | |
3797 | { | |
3798 | u64 sample_type = data->type; | |
3799 | ||
3800 | if (sample_type & PERF_SAMPLE_TID) | |
3801 | perf_output_put(handle, data->tid_entry); | |
3802 | ||
3803 | if (sample_type & PERF_SAMPLE_TIME) | |
3804 | perf_output_put(handle, data->time); | |
3805 | ||
3806 | if (sample_type & PERF_SAMPLE_ID) | |
3807 | perf_output_put(handle, data->id); | |
3808 | ||
3809 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
3810 | perf_output_put(handle, data->stream_id); | |
3811 | ||
3812 | if (sample_type & PERF_SAMPLE_CPU) | |
3813 | perf_output_put(handle, data->cpu_entry); | |
3814 | } | |
3815 | ||
76369139 FW |
3816 | void perf_event__output_id_sample(struct perf_event *event, |
3817 | struct perf_output_handle *handle, | |
3818 | struct perf_sample_data *sample) | |
c980d109 ACM |
3819 | { |
3820 | if (event->attr.sample_id_all) | |
3821 | __perf_event__output_id_sample(handle, sample); | |
3822 | } | |
3823 | ||
3dab77fb | 3824 | static void perf_output_read_one(struct perf_output_handle *handle, |
eed01528 SE |
3825 | struct perf_event *event, |
3826 | u64 enabled, u64 running) | |
3dab77fb | 3827 | { |
cdd6c482 | 3828 | u64 read_format = event->attr.read_format; |
3dab77fb PZ |
3829 | u64 values[4]; |
3830 | int n = 0; | |
3831 | ||
b5e58793 | 3832 | values[n++] = perf_event_count(event); |
3dab77fb | 3833 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { |
eed01528 | 3834 | values[n++] = enabled + |
cdd6c482 | 3835 | atomic64_read(&event->child_total_time_enabled); |
3dab77fb PZ |
3836 | } |
3837 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { | |
eed01528 | 3838 | values[n++] = running + |
cdd6c482 | 3839 | atomic64_read(&event->child_total_time_running); |
3dab77fb PZ |
3840 | } |
3841 | if (read_format & PERF_FORMAT_ID) | |
cdd6c482 | 3842 | values[n++] = primary_event_id(event); |
3dab77fb | 3843 | |
76369139 | 3844 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
3845 | } |
3846 | ||
3847 | /* | |
cdd6c482 | 3848 | * XXX PERF_FORMAT_GROUP vs inherited events seems difficult. |
3dab77fb PZ |
3849 | */ |
3850 | static void perf_output_read_group(struct perf_output_handle *handle, | |
eed01528 SE |
3851 | struct perf_event *event, |
3852 | u64 enabled, u64 running) | |
3dab77fb | 3853 | { |
cdd6c482 IM |
3854 | struct perf_event *leader = event->group_leader, *sub; |
3855 | u64 read_format = event->attr.read_format; | |
3dab77fb PZ |
3856 | u64 values[5]; |
3857 | int n = 0; | |
3858 | ||
3859 | values[n++] = 1 + leader->nr_siblings; | |
3860 | ||
3861 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
eed01528 | 3862 | values[n++] = enabled; |
3dab77fb PZ |
3863 | |
3864 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
eed01528 | 3865 | values[n++] = running; |
3dab77fb | 3866 | |
cdd6c482 | 3867 | if (leader != event) |
3dab77fb PZ |
3868 | leader->pmu->read(leader); |
3869 | ||
b5e58793 | 3870 | values[n++] = perf_event_count(leader); |
3dab77fb | 3871 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 3872 | values[n++] = primary_event_id(leader); |
3dab77fb | 3873 | |
76369139 | 3874 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb | 3875 | |
65abc865 | 3876 | list_for_each_entry(sub, &leader->sibling_list, group_entry) { |
3dab77fb PZ |
3877 | n = 0; |
3878 | ||
cdd6c482 | 3879 | if (sub != event) |
3dab77fb PZ |
3880 | sub->pmu->read(sub); |
3881 | ||
b5e58793 | 3882 | values[n++] = perf_event_count(sub); |
3dab77fb | 3883 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 3884 | values[n++] = primary_event_id(sub); |
3dab77fb | 3885 | |
76369139 | 3886 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
3887 | } |
3888 | } | |
3889 | ||
eed01528 SE |
3890 | #define PERF_FORMAT_TOTAL_TIMES (PERF_FORMAT_TOTAL_TIME_ENABLED|\ |
3891 | PERF_FORMAT_TOTAL_TIME_RUNNING) | |
3892 | ||
3dab77fb | 3893 | static void perf_output_read(struct perf_output_handle *handle, |
cdd6c482 | 3894 | struct perf_event *event) |
3dab77fb | 3895 | { |
e3f3541c | 3896 | u64 enabled = 0, running = 0, now; |
eed01528 SE |
3897 | u64 read_format = event->attr.read_format; |
3898 | ||
3899 | /* | |
3900 | * compute total_time_enabled, total_time_running | |
3901 | * based on snapshot values taken when the event | |
3902 | * was last scheduled in. | |
3903 | * | |
3904 | * we cannot simply called update_context_time() | |
3905 | * because of locking issue as we are called in | |
3906 | * NMI context | |
3907 | */ | |
c4794295 | 3908 | if (read_format & PERF_FORMAT_TOTAL_TIMES) |
e3f3541c | 3909 | calc_timer_values(event, &now, &enabled, &running); |
eed01528 | 3910 | |
cdd6c482 | 3911 | if (event->attr.read_format & PERF_FORMAT_GROUP) |
eed01528 | 3912 | perf_output_read_group(handle, event, enabled, running); |
3dab77fb | 3913 | else |
eed01528 | 3914 | perf_output_read_one(handle, event, enabled, running); |
3dab77fb PZ |
3915 | } |
3916 | ||
5622f295 MM |
3917 | void perf_output_sample(struct perf_output_handle *handle, |
3918 | struct perf_event_header *header, | |
3919 | struct perf_sample_data *data, | |
cdd6c482 | 3920 | struct perf_event *event) |
5622f295 MM |
3921 | { |
3922 | u64 sample_type = data->type; | |
3923 | ||
3924 | perf_output_put(handle, *header); | |
3925 | ||
3926 | if (sample_type & PERF_SAMPLE_IP) | |
3927 | perf_output_put(handle, data->ip); | |
3928 | ||
3929 | if (sample_type & PERF_SAMPLE_TID) | |
3930 | perf_output_put(handle, data->tid_entry); | |
3931 | ||
3932 | if (sample_type & PERF_SAMPLE_TIME) | |
3933 | perf_output_put(handle, data->time); | |
3934 | ||
3935 | if (sample_type & PERF_SAMPLE_ADDR) | |
3936 | perf_output_put(handle, data->addr); | |
3937 | ||
3938 | if (sample_type & PERF_SAMPLE_ID) | |
3939 | perf_output_put(handle, data->id); | |
3940 | ||
3941 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
3942 | perf_output_put(handle, data->stream_id); | |
3943 | ||
3944 | if (sample_type & PERF_SAMPLE_CPU) | |
3945 | perf_output_put(handle, data->cpu_entry); | |
3946 | ||
3947 | if (sample_type & PERF_SAMPLE_PERIOD) | |
3948 | perf_output_put(handle, data->period); | |
3949 | ||
3950 | if (sample_type & PERF_SAMPLE_READ) | |
cdd6c482 | 3951 | perf_output_read(handle, event); |
5622f295 MM |
3952 | |
3953 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { | |
3954 | if (data->callchain) { | |
3955 | int size = 1; | |
3956 | ||
3957 | if (data->callchain) | |
3958 | size += data->callchain->nr; | |
3959 | ||
3960 | size *= sizeof(u64); | |
3961 | ||
76369139 | 3962 | __output_copy(handle, data->callchain, size); |
5622f295 MM |
3963 | } else { |
3964 | u64 nr = 0; | |
3965 | perf_output_put(handle, nr); | |
3966 | } | |
3967 | } | |
3968 | ||
3969 | if (sample_type & PERF_SAMPLE_RAW) { | |
3970 | if (data->raw) { | |
3971 | perf_output_put(handle, data->raw->size); | |
76369139 FW |
3972 | __output_copy(handle, data->raw->data, |
3973 | data->raw->size); | |
5622f295 MM |
3974 | } else { |
3975 | struct { | |
3976 | u32 size; | |
3977 | u32 data; | |
3978 | } raw = { | |
3979 | .size = sizeof(u32), | |
3980 | .data = 0, | |
3981 | }; | |
3982 | perf_output_put(handle, raw); | |
3983 | } | |
3984 | } | |
a7ac67ea PZ |
3985 | |
3986 | if (!event->attr.watermark) { | |
3987 | int wakeup_events = event->attr.wakeup_events; | |
3988 | ||
3989 | if (wakeup_events) { | |
3990 | struct ring_buffer *rb = handle->rb; | |
3991 | int events = local_inc_return(&rb->events); | |
3992 | ||
3993 | if (events >= wakeup_events) { | |
3994 | local_sub(wakeup_events, &rb->events); | |
3995 | local_inc(&rb->wakeup); | |
3996 | } | |
3997 | } | |
3998 | } | |
bce38cd5 SE |
3999 | |
4000 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { | |
4001 | if (data->br_stack) { | |
4002 | size_t size; | |
4003 | ||
4004 | size = data->br_stack->nr | |
4005 | * sizeof(struct perf_branch_entry); | |
4006 | ||
4007 | perf_output_put(handle, data->br_stack->nr); | |
4008 | perf_output_copy(handle, data->br_stack->entries, size); | |
4009 | } else { | |
4010 | /* | |
4011 | * we always store at least the value of nr | |
4012 | */ | |
4013 | u64 nr = 0; | |
4014 | perf_output_put(handle, nr); | |
4015 | } | |
4016 | } | |
5622f295 MM |
4017 | } |
4018 | ||
4019 | void perf_prepare_sample(struct perf_event_header *header, | |
4020 | struct perf_sample_data *data, | |
cdd6c482 | 4021 | struct perf_event *event, |
5622f295 | 4022 | struct pt_regs *regs) |
7b732a75 | 4023 | { |
cdd6c482 | 4024 | u64 sample_type = event->attr.sample_type; |
7b732a75 | 4025 | |
cdd6c482 | 4026 | header->type = PERF_RECORD_SAMPLE; |
c320c7b7 | 4027 | header->size = sizeof(*header) + event->header_size; |
5622f295 MM |
4028 | |
4029 | header->misc = 0; | |
4030 | header->misc |= perf_misc_flags(regs); | |
6fab0192 | 4031 | |
c980d109 | 4032 | __perf_event_header__init_id(header, data, event); |
6844c09d | 4033 | |
c320c7b7 | 4034 | if (sample_type & PERF_SAMPLE_IP) |
5622f295 MM |
4035 | data->ip = perf_instruction_pointer(regs); |
4036 | ||
b23f3325 | 4037 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { |
5622f295 | 4038 | int size = 1; |
394ee076 | 4039 | |
5622f295 MM |
4040 | data->callchain = perf_callchain(regs); |
4041 | ||
4042 | if (data->callchain) | |
4043 | size += data->callchain->nr; | |
4044 | ||
4045 | header->size += size * sizeof(u64); | |
394ee076 PZ |
4046 | } |
4047 | ||
3a43ce68 | 4048 | if (sample_type & PERF_SAMPLE_RAW) { |
a044560c PZ |
4049 | int size = sizeof(u32); |
4050 | ||
4051 | if (data->raw) | |
4052 | size += data->raw->size; | |
4053 | else | |
4054 | size += sizeof(u32); | |
4055 | ||
4056 | WARN_ON_ONCE(size & (sizeof(u64)-1)); | |
5622f295 | 4057 | header->size += size; |
7f453c24 | 4058 | } |
bce38cd5 SE |
4059 | |
4060 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { | |
4061 | int size = sizeof(u64); /* nr */ | |
4062 | if (data->br_stack) { | |
4063 | size += data->br_stack->nr | |
4064 | * sizeof(struct perf_branch_entry); | |
4065 | } | |
4066 | header->size += size; | |
4067 | } | |
5622f295 | 4068 | } |
7f453c24 | 4069 | |
a8b0ca17 | 4070 | static void perf_event_output(struct perf_event *event, |
5622f295 MM |
4071 | struct perf_sample_data *data, |
4072 | struct pt_regs *regs) | |
4073 | { | |
4074 | struct perf_output_handle handle; | |
4075 | struct perf_event_header header; | |
689802b2 | 4076 | |
927c7a9e FW |
4077 | /* protect the callchain buffers */ |
4078 | rcu_read_lock(); | |
4079 | ||
cdd6c482 | 4080 | perf_prepare_sample(&header, data, event, regs); |
5c148194 | 4081 | |
a7ac67ea | 4082 | if (perf_output_begin(&handle, event, header.size)) |
927c7a9e | 4083 | goto exit; |
0322cd6e | 4084 | |
cdd6c482 | 4085 | perf_output_sample(&handle, &header, data, event); |
f413cdb8 | 4086 | |
8a057d84 | 4087 | perf_output_end(&handle); |
927c7a9e FW |
4088 | |
4089 | exit: | |
4090 | rcu_read_unlock(); | |
0322cd6e PZ |
4091 | } |
4092 | ||
38b200d6 | 4093 | /* |
cdd6c482 | 4094 | * read event_id |
38b200d6 PZ |
4095 | */ |
4096 | ||
4097 | struct perf_read_event { | |
4098 | struct perf_event_header header; | |
4099 | ||
4100 | u32 pid; | |
4101 | u32 tid; | |
38b200d6 PZ |
4102 | }; |
4103 | ||
4104 | static void | |
cdd6c482 | 4105 | perf_event_read_event(struct perf_event *event, |
38b200d6 PZ |
4106 | struct task_struct *task) |
4107 | { | |
4108 | struct perf_output_handle handle; | |
c980d109 | 4109 | struct perf_sample_data sample; |
dfc65094 | 4110 | struct perf_read_event read_event = { |
38b200d6 | 4111 | .header = { |
cdd6c482 | 4112 | .type = PERF_RECORD_READ, |
38b200d6 | 4113 | .misc = 0, |
c320c7b7 | 4114 | .size = sizeof(read_event) + event->read_size, |
38b200d6 | 4115 | }, |
cdd6c482 IM |
4116 | .pid = perf_event_pid(event, task), |
4117 | .tid = perf_event_tid(event, task), | |
38b200d6 | 4118 | }; |
3dab77fb | 4119 | int ret; |
38b200d6 | 4120 | |
c980d109 | 4121 | perf_event_header__init_id(&read_event.header, &sample, event); |
a7ac67ea | 4122 | ret = perf_output_begin(&handle, event, read_event.header.size); |
38b200d6 PZ |
4123 | if (ret) |
4124 | return; | |
4125 | ||
dfc65094 | 4126 | perf_output_put(&handle, read_event); |
cdd6c482 | 4127 | perf_output_read(&handle, event); |
c980d109 | 4128 | perf_event__output_id_sample(event, &handle, &sample); |
3dab77fb | 4129 | |
38b200d6 PZ |
4130 | perf_output_end(&handle); |
4131 | } | |
4132 | ||
60313ebe | 4133 | /* |
9f498cc5 PZ |
4134 | * task tracking -- fork/exit |
4135 | * | |
3af9e859 | 4136 | * enabled by: attr.comm | attr.mmap | attr.mmap_data | attr.task |
60313ebe PZ |
4137 | */ |
4138 | ||
9f498cc5 | 4139 | struct perf_task_event { |
3a80b4a3 | 4140 | struct task_struct *task; |
cdd6c482 | 4141 | struct perf_event_context *task_ctx; |
60313ebe PZ |
4142 | |
4143 | struct { | |
4144 | struct perf_event_header header; | |
4145 | ||
4146 | u32 pid; | |
4147 | u32 ppid; | |
9f498cc5 PZ |
4148 | u32 tid; |
4149 | u32 ptid; | |
393b2ad8 | 4150 | u64 time; |
cdd6c482 | 4151 | } event_id; |
60313ebe PZ |
4152 | }; |
4153 | ||
cdd6c482 | 4154 | static void perf_event_task_output(struct perf_event *event, |
9f498cc5 | 4155 | struct perf_task_event *task_event) |
60313ebe PZ |
4156 | { |
4157 | struct perf_output_handle handle; | |
c980d109 | 4158 | struct perf_sample_data sample; |
9f498cc5 | 4159 | struct task_struct *task = task_event->task; |
c980d109 | 4160 | int ret, size = task_event->event_id.header.size; |
8bb39f9a | 4161 | |
c980d109 | 4162 | perf_event_header__init_id(&task_event->event_id.header, &sample, event); |
60313ebe | 4163 | |
c980d109 | 4164 | ret = perf_output_begin(&handle, event, |
a7ac67ea | 4165 | task_event->event_id.header.size); |
ef60777c | 4166 | if (ret) |
c980d109 | 4167 | goto out; |
60313ebe | 4168 | |
cdd6c482 IM |
4169 | task_event->event_id.pid = perf_event_pid(event, task); |
4170 | task_event->event_id.ppid = perf_event_pid(event, current); | |
60313ebe | 4171 | |
cdd6c482 IM |
4172 | task_event->event_id.tid = perf_event_tid(event, task); |
4173 | task_event->event_id.ptid = perf_event_tid(event, current); | |
9f498cc5 | 4174 | |
cdd6c482 | 4175 | perf_output_put(&handle, task_event->event_id); |
393b2ad8 | 4176 | |
c980d109 ACM |
4177 | perf_event__output_id_sample(event, &handle, &sample); |
4178 | ||
60313ebe | 4179 | perf_output_end(&handle); |
c980d109 ACM |
4180 | out: |
4181 | task_event->event_id.header.size = size; | |
60313ebe PZ |
4182 | } |
4183 | ||
cdd6c482 | 4184 | static int perf_event_task_match(struct perf_event *event) |
60313ebe | 4185 | { |
6f93d0a7 | 4186 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
22e19085 PZ |
4187 | return 0; |
4188 | ||
5632ab12 | 4189 | if (!event_filter_match(event)) |
5d27c23d PZ |
4190 | return 0; |
4191 | ||
3af9e859 EM |
4192 | if (event->attr.comm || event->attr.mmap || |
4193 | event->attr.mmap_data || event->attr.task) | |
60313ebe PZ |
4194 | return 1; |
4195 | ||
4196 | return 0; | |
4197 | } | |
4198 | ||
cdd6c482 | 4199 | static void perf_event_task_ctx(struct perf_event_context *ctx, |
9f498cc5 | 4200 | struct perf_task_event *task_event) |
60313ebe | 4201 | { |
cdd6c482 | 4202 | struct perf_event *event; |
60313ebe | 4203 | |
cdd6c482 IM |
4204 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { |
4205 | if (perf_event_task_match(event)) | |
4206 | perf_event_task_output(event, task_event); | |
60313ebe | 4207 | } |
60313ebe PZ |
4208 | } |
4209 | ||
cdd6c482 | 4210 | static void perf_event_task_event(struct perf_task_event *task_event) |
60313ebe PZ |
4211 | { |
4212 | struct perf_cpu_context *cpuctx; | |
8dc85d54 | 4213 | struct perf_event_context *ctx; |
108b02cf | 4214 | struct pmu *pmu; |
8dc85d54 | 4215 | int ctxn; |
60313ebe | 4216 | |
d6ff86cf | 4217 | rcu_read_lock(); |
108b02cf | 4218 | list_for_each_entry_rcu(pmu, &pmus, entry) { |
41945f6c | 4219 | cpuctx = get_cpu_ptr(pmu->pmu_cpu_context); |
51676957 PZ |
4220 | if (cpuctx->active_pmu != pmu) |
4221 | goto next; | |
108b02cf | 4222 | perf_event_task_ctx(&cpuctx->ctx, task_event); |
8dc85d54 PZ |
4223 | |
4224 | ctx = task_event->task_ctx; | |
4225 | if (!ctx) { | |
4226 | ctxn = pmu->task_ctx_nr; | |
4227 | if (ctxn < 0) | |
41945f6c | 4228 | goto next; |
8dc85d54 PZ |
4229 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); |
4230 | } | |
4231 | if (ctx) | |
4232 | perf_event_task_ctx(ctx, task_event); | |
41945f6c PZ |
4233 | next: |
4234 | put_cpu_ptr(pmu->pmu_cpu_context); | |
108b02cf | 4235 | } |
60313ebe PZ |
4236 | rcu_read_unlock(); |
4237 | } | |
4238 | ||
cdd6c482 IM |
4239 | static void perf_event_task(struct task_struct *task, |
4240 | struct perf_event_context *task_ctx, | |
3a80b4a3 | 4241 | int new) |
60313ebe | 4242 | { |
9f498cc5 | 4243 | struct perf_task_event task_event; |
60313ebe | 4244 | |
cdd6c482 IM |
4245 | if (!atomic_read(&nr_comm_events) && |
4246 | !atomic_read(&nr_mmap_events) && | |
4247 | !atomic_read(&nr_task_events)) | |
60313ebe PZ |
4248 | return; |
4249 | ||
9f498cc5 | 4250 | task_event = (struct perf_task_event){ |
3a80b4a3 PZ |
4251 | .task = task, |
4252 | .task_ctx = task_ctx, | |
cdd6c482 | 4253 | .event_id = { |
60313ebe | 4254 | .header = { |
cdd6c482 | 4255 | .type = new ? PERF_RECORD_FORK : PERF_RECORD_EXIT, |
573402db | 4256 | .misc = 0, |
cdd6c482 | 4257 | .size = sizeof(task_event.event_id), |
60313ebe | 4258 | }, |
573402db PZ |
4259 | /* .pid */ |
4260 | /* .ppid */ | |
9f498cc5 PZ |
4261 | /* .tid */ |
4262 | /* .ptid */ | |
6f93d0a7 | 4263 | .time = perf_clock(), |
60313ebe PZ |
4264 | }, |
4265 | }; | |
4266 | ||
cdd6c482 | 4267 | perf_event_task_event(&task_event); |
9f498cc5 PZ |
4268 | } |
4269 | ||
cdd6c482 | 4270 | void perf_event_fork(struct task_struct *task) |
9f498cc5 | 4271 | { |
cdd6c482 | 4272 | perf_event_task(task, NULL, 1); |
60313ebe PZ |
4273 | } |
4274 | ||
8d1b2d93 PZ |
4275 | /* |
4276 | * comm tracking | |
4277 | */ | |
4278 | ||
4279 | struct perf_comm_event { | |
22a4f650 IM |
4280 | struct task_struct *task; |
4281 | char *comm; | |
8d1b2d93 PZ |
4282 | int comm_size; |
4283 | ||
4284 | struct { | |
4285 | struct perf_event_header header; | |
4286 | ||
4287 | u32 pid; | |
4288 | u32 tid; | |
cdd6c482 | 4289 | } event_id; |
8d1b2d93 PZ |
4290 | }; |
4291 | ||
cdd6c482 | 4292 | static void perf_event_comm_output(struct perf_event *event, |
8d1b2d93 PZ |
4293 | struct perf_comm_event *comm_event) |
4294 | { | |
4295 | struct perf_output_handle handle; | |
c980d109 | 4296 | struct perf_sample_data sample; |
cdd6c482 | 4297 | int size = comm_event->event_id.header.size; |
c980d109 ACM |
4298 | int ret; |
4299 | ||
4300 | perf_event_header__init_id(&comm_event->event_id.header, &sample, event); | |
4301 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 4302 | comm_event->event_id.header.size); |
8d1b2d93 PZ |
4303 | |
4304 | if (ret) | |
c980d109 | 4305 | goto out; |
8d1b2d93 | 4306 | |
cdd6c482 IM |
4307 | comm_event->event_id.pid = perf_event_pid(event, comm_event->task); |
4308 | comm_event->event_id.tid = perf_event_tid(event, comm_event->task); | |
709e50cf | 4309 | |
cdd6c482 | 4310 | perf_output_put(&handle, comm_event->event_id); |
76369139 | 4311 | __output_copy(&handle, comm_event->comm, |
8d1b2d93 | 4312 | comm_event->comm_size); |
c980d109 ACM |
4313 | |
4314 | perf_event__output_id_sample(event, &handle, &sample); | |
4315 | ||
8d1b2d93 | 4316 | perf_output_end(&handle); |
c980d109 ACM |
4317 | out: |
4318 | comm_event->event_id.header.size = size; | |
8d1b2d93 PZ |
4319 | } |
4320 | ||
cdd6c482 | 4321 | static int perf_event_comm_match(struct perf_event *event) |
8d1b2d93 | 4322 | { |
6f93d0a7 | 4323 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
22e19085 PZ |
4324 | return 0; |
4325 | ||
5632ab12 | 4326 | if (!event_filter_match(event)) |
5d27c23d PZ |
4327 | return 0; |
4328 | ||
cdd6c482 | 4329 | if (event->attr.comm) |
8d1b2d93 PZ |
4330 | return 1; |
4331 | ||
4332 | return 0; | |
4333 | } | |
4334 | ||
cdd6c482 | 4335 | static void perf_event_comm_ctx(struct perf_event_context *ctx, |
8d1b2d93 PZ |
4336 | struct perf_comm_event *comm_event) |
4337 | { | |
cdd6c482 | 4338 | struct perf_event *event; |
8d1b2d93 | 4339 | |
cdd6c482 IM |
4340 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { |
4341 | if (perf_event_comm_match(event)) | |
4342 | perf_event_comm_output(event, comm_event); | |
8d1b2d93 | 4343 | } |
8d1b2d93 PZ |
4344 | } |
4345 | ||
cdd6c482 | 4346 | static void perf_event_comm_event(struct perf_comm_event *comm_event) |
8d1b2d93 PZ |
4347 | { |
4348 | struct perf_cpu_context *cpuctx; | |
cdd6c482 | 4349 | struct perf_event_context *ctx; |
413ee3b4 | 4350 | char comm[TASK_COMM_LEN]; |
8d1b2d93 | 4351 | unsigned int size; |
108b02cf | 4352 | struct pmu *pmu; |
8dc85d54 | 4353 | int ctxn; |
8d1b2d93 | 4354 | |
413ee3b4 | 4355 | memset(comm, 0, sizeof(comm)); |
96b02d78 | 4356 | strlcpy(comm, comm_event->task->comm, sizeof(comm)); |
888fcee0 | 4357 | size = ALIGN(strlen(comm)+1, sizeof(u64)); |
8d1b2d93 PZ |
4358 | |
4359 | comm_event->comm = comm; | |
4360 | comm_event->comm_size = size; | |
4361 | ||
cdd6c482 | 4362 | comm_event->event_id.header.size = sizeof(comm_event->event_id) + size; |
f6595f3a | 4363 | rcu_read_lock(); |
108b02cf | 4364 | list_for_each_entry_rcu(pmu, &pmus, entry) { |
41945f6c | 4365 | cpuctx = get_cpu_ptr(pmu->pmu_cpu_context); |
51676957 PZ |
4366 | if (cpuctx->active_pmu != pmu) |
4367 | goto next; | |
108b02cf | 4368 | perf_event_comm_ctx(&cpuctx->ctx, comm_event); |
8dc85d54 PZ |
4369 | |
4370 | ctxn = pmu->task_ctx_nr; | |
4371 | if (ctxn < 0) | |
41945f6c | 4372 | goto next; |
8dc85d54 PZ |
4373 | |
4374 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); | |
4375 | if (ctx) | |
4376 | perf_event_comm_ctx(ctx, comm_event); | |
41945f6c PZ |
4377 | next: |
4378 | put_cpu_ptr(pmu->pmu_cpu_context); | |
108b02cf | 4379 | } |
665c2142 | 4380 | rcu_read_unlock(); |
8d1b2d93 PZ |
4381 | } |
4382 | ||
cdd6c482 | 4383 | void perf_event_comm(struct task_struct *task) |
8d1b2d93 | 4384 | { |
9ee318a7 | 4385 | struct perf_comm_event comm_event; |
8dc85d54 PZ |
4386 | struct perf_event_context *ctx; |
4387 | int ctxn; | |
9ee318a7 | 4388 | |
8dc85d54 PZ |
4389 | for_each_task_context_nr(ctxn) { |
4390 | ctx = task->perf_event_ctxp[ctxn]; | |
4391 | if (!ctx) | |
4392 | continue; | |
9ee318a7 | 4393 | |
8dc85d54 PZ |
4394 | perf_event_enable_on_exec(ctx); |
4395 | } | |
9ee318a7 | 4396 | |
cdd6c482 | 4397 | if (!atomic_read(&nr_comm_events)) |
9ee318a7 | 4398 | return; |
a63eaf34 | 4399 | |
9ee318a7 | 4400 | comm_event = (struct perf_comm_event){ |
8d1b2d93 | 4401 | .task = task, |
573402db PZ |
4402 | /* .comm */ |
4403 | /* .comm_size */ | |
cdd6c482 | 4404 | .event_id = { |
573402db | 4405 | .header = { |
cdd6c482 | 4406 | .type = PERF_RECORD_COMM, |
573402db PZ |
4407 | .misc = 0, |
4408 | /* .size */ | |
4409 | }, | |
4410 | /* .pid */ | |
4411 | /* .tid */ | |
8d1b2d93 PZ |
4412 | }, |
4413 | }; | |
4414 | ||
cdd6c482 | 4415 | perf_event_comm_event(&comm_event); |
8d1b2d93 PZ |
4416 | } |
4417 | ||
0a4a9391 PZ |
4418 | /* |
4419 | * mmap tracking | |
4420 | */ | |
4421 | ||
4422 | struct perf_mmap_event { | |
089dd79d PZ |
4423 | struct vm_area_struct *vma; |
4424 | ||
4425 | const char *file_name; | |
4426 | int file_size; | |
0a4a9391 PZ |
4427 | |
4428 | struct { | |
4429 | struct perf_event_header header; | |
4430 | ||
4431 | u32 pid; | |
4432 | u32 tid; | |
4433 | u64 start; | |
4434 | u64 len; | |
4435 | u64 pgoff; | |
cdd6c482 | 4436 | } event_id; |
0a4a9391 PZ |
4437 | }; |
4438 | ||
cdd6c482 | 4439 | static void perf_event_mmap_output(struct perf_event *event, |
0a4a9391 PZ |
4440 | struct perf_mmap_event *mmap_event) |
4441 | { | |
4442 | struct perf_output_handle handle; | |
c980d109 | 4443 | struct perf_sample_data sample; |
cdd6c482 | 4444 | int size = mmap_event->event_id.header.size; |
c980d109 | 4445 | int ret; |
0a4a9391 | 4446 | |
c980d109 ACM |
4447 | perf_event_header__init_id(&mmap_event->event_id.header, &sample, event); |
4448 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 4449 | mmap_event->event_id.header.size); |
0a4a9391 | 4450 | if (ret) |
c980d109 | 4451 | goto out; |
0a4a9391 | 4452 | |
cdd6c482 IM |
4453 | mmap_event->event_id.pid = perf_event_pid(event, current); |
4454 | mmap_event->event_id.tid = perf_event_tid(event, current); | |
709e50cf | 4455 | |
cdd6c482 | 4456 | perf_output_put(&handle, mmap_event->event_id); |
76369139 | 4457 | __output_copy(&handle, mmap_event->file_name, |
0a4a9391 | 4458 | mmap_event->file_size); |
c980d109 ACM |
4459 | |
4460 | perf_event__output_id_sample(event, &handle, &sample); | |
4461 | ||
78d613eb | 4462 | perf_output_end(&handle); |
c980d109 ACM |
4463 | out: |
4464 | mmap_event->event_id.header.size = size; | |
0a4a9391 PZ |
4465 | } |
4466 | ||
cdd6c482 | 4467 | static int perf_event_mmap_match(struct perf_event *event, |
3af9e859 EM |
4468 | struct perf_mmap_event *mmap_event, |
4469 | int executable) | |
0a4a9391 | 4470 | { |
6f93d0a7 | 4471 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
22e19085 PZ |
4472 | return 0; |
4473 | ||
5632ab12 | 4474 | if (!event_filter_match(event)) |
5d27c23d PZ |
4475 | return 0; |
4476 | ||
3af9e859 EM |
4477 | if ((!executable && event->attr.mmap_data) || |
4478 | (executable && event->attr.mmap)) | |
0a4a9391 PZ |
4479 | return 1; |
4480 | ||
4481 | return 0; | |
4482 | } | |
4483 | ||
cdd6c482 | 4484 | static void perf_event_mmap_ctx(struct perf_event_context *ctx, |
3af9e859 EM |
4485 | struct perf_mmap_event *mmap_event, |
4486 | int executable) | |
0a4a9391 | 4487 | { |
cdd6c482 | 4488 | struct perf_event *event; |
0a4a9391 | 4489 | |
cdd6c482 | 4490 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { |
3af9e859 | 4491 | if (perf_event_mmap_match(event, mmap_event, executable)) |
cdd6c482 | 4492 | perf_event_mmap_output(event, mmap_event); |
0a4a9391 | 4493 | } |
0a4a9391 PZ |
4494 | } |
4495 | ||
cdd6c482 | 4496 | static void perf_event_mmap_event(struct perf_mmap_event *mmap_event) |
0a4a9391 PZ |
4497 | { |
4498 | struct perf_cpu_context *cpuctx; | |
cdd6c482 | 4499 | struct perf_event_context *ctx; |
089dd79d PZ |
4500 | struct vm_area_struct *vma = mmap_event->vma; |
4501 | struct file *file = vma->vm_file; | |
0a4a9391 PZ |
4502 | unsigned int size; |
4503 | char tmp[16]; | |
4504 | char *buf = NULL; | |
089dd79d | 4505 | const char *name; |
108b02cf | 4506 | struct pmu *pmu; |
8dc85d54 | 4507 | int ctxn; |
0a4a9391 | 4508 | |
413ee3b4 AB |
4509 | memset(tmp, 0, sizeof(tmp)); |
4510 | ||
0a4a9391 | 4511 | if (file) { |
413ee3b4 | 4512 | /* |
76369139 | 4513 | * d_path works from the end of the rb backwards, so we |
413ee3b4 AB |
4514 | * need to add enough zero bytes after the string to handle |
4515 | * the 64bit alignment we do later. | |
4516 | */ | |
4517 | buf = kzalloc(PATH_MAX + sizeof(u64), GFP_KERNEL); | |
0a4a9391 PZ |
4518 | if (!buf) { |
4519 | name = strncpy(tmp, "//enomem", sizeof(tmp)); | |
4520 | goto got_name; | |
4521 | } | |
d3d21c41 | 4522 | name = d_path(&file->f_path, buf, PATH_MAX); |
0a4a9391 PZ |
4523 | if (IS_ERR(name)) { |
4524 | name = strncpy(tmp, "//toolong", sizeof(tmp)); | |
4525 | goto got_name; | |
4526 | } | |
4527 | } else { | |
413ee3b4 AB |
4528 | if (arch_vma_name(mmap_event->vma)) { |
4529 | name = strncpy(tmp, arch_vma_name(mmap_event->vma), | |
4530 | sizeof(tmp)); | |
089dd79d | 4531 | goto got_name; |
413ee3b4 | 4532 | } |
089dd79d PZ |
4533 | |
4534 | if (!vma->vm_mm) { | |
4535 | name = strncpy(tmp, "[vdso]", sizeof(tmp)); | |
4536 | goto got_name; | |
3af9e859 EM |
4537 | } else if (vma->vm_start <= vma->vm_mm->start_brk && |
4538 | vma->vm_end >= vma->vm_mm->brk) { | |
4539 | name = strncpy(tmp, "[heap]", sizeof(tmp)); | |
4540 | goto got_name; | |
4541 | } else if (vma->vm_start <= vma->vm_mm->start_stack && | |
4542 | vma->vm_end >= vma->vm_mm->start_stack) { | |
4543 | name = strncpy(tmp, "[stack]", sizeof(tmp)); | |
4544 | goto got_name; | |
089dd79d PZ |
4545 | } |
4546 | ||
0a4a9391 PZ |
4547 | name = strncpy(tmp, "//anon", sizeof(tmp)); |
4548 | goto got_name; | |
4549 | } | |
4550 | ||
4551 | got_name: | |
888fcee0 | 4552 | size = ALIGN(strlen(name)+1, sizeof(u64)); |
0a4a9391 PZ |
4553 | |
4554 | mmap_event->file_name = name; | |
4555 | mmap_event->file_size = size; | |
4556 | ||
cdd6c482 | 4557 | mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size; |
0a4a9391 | 4558 | |
f6d9dd23 | 4559 | rcu_read_lock(); |
108b02cf | 4560 | list_for_each_entry_rcu(pmu, &pmus, entry) { |
41945f6c | 4561 | cpuctx = get_cpu_ptr(pmu->pmu_cpu_context); |
51676957 PZ |
4562 | if (cpuctx->active_pmu != pmu) |
4563 | goto next; | |
108b02cf PZ |
4564 | perf_event_mmap_ctx(&cpuctx->ctx, mmap_event, |
4565 | vma->vm_flags & VM_EXEC); | |
8dc85d54 PZ |
4566 | |
4567 | ctxn = pmu->task_ctx_nr; | |
4568 | if (ctxn < 0) | |
41945f6c | 4569 | goto next; |
8dc85d54 PZ |
4570 | |
4571 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); | |
4572 | if (ctx) { | |
4573 | perf_event_mmap_ctx(ctx, mmap_event, | |
4574 | vma->vm_flags & VM_EXEC); | |
4575 | } | |
41945f6c PZ |
4576 | next: |
4577 | put_cpu_ptr(pmu->pmu_cpu_context); | |
108b02cf | 4578 | } |
665c2142 PZ |
4579 | rcu_read_unlock(); |
4580 | ||
0a4a9391 PZ |
4581 | kfree(buf); |
4582 | } | |
4583 | ||
3af9e859 | 4584 | void perf_event_mmap(struct vm_area_struct *vma) |
0a4a9391 | 4585 | { |
9ee318a7 PZ |
4586 | struct perf_mmap_event mmap_event; |
4587 | ||
cdd6c482 | 4588 | if (!atomic_read(&nr_mmap_events)) |
9ee318a7 PZ |
4589 | return; |
4590 | ||
4591 | mmap_event = (struct perf_mmap_event){ | |
089dd79d | 4592 | .vma = vma, |
573402db PZ |
4593 | /* .file_name */ |
4594 | /* .file_size */ | |
cdd6c482 | 4595 | .event_id = { |
573402db | 4596 | .header = { |
cdd6c482 | 4597 | .type = PERF_RECORD_MMAP, |
39447b38 | 4598 | .misc = PERF_RECORD_MISC_USER, |
573402db PZ |
4599 | /* .size */ |
4600 | }, | |
4601 | /* .pid */ | |
4602 | /* .tid */ | |
089dd79d PZ |
4603 | .start = vma->vm_start, |
4604 | .len = vma->vm_end - vma->vm_start, | |
3a0304e9 | 4605 | .pgoff = (u64)vma->vm_pgoff << PAGE_SHIFT, |
0a4a9391 PZ |
4606 | }, |
4607 | }; | |
4608 | ||
cdd6c482 | 4609 | perf_event_mmap_event(&mmap_event); |
0a4a9391 PZ |
4610 | } |
4611 | ||
a78ac325 PZ |
4612 | /* |
4613 | * IRQ throttle logging | |
4614 | */ | |
4615 | ||
cdd6c482 | 4616 | static void perf_log_throttle(struct perf_event *event, int enable) |
a78ac325 PZ |
4617 | { |
4618 | struct perf_output_handle handle; | |
c980d109 | 4619 | struct perf_sample_data sample; |
a78ac325 PZ |
4620 | int ret; |
4621 | ||
4622 | struct { | |
4623 | struct perf_event_header header; | |
4624 | u64 time; | |
cca3f454 | 4625 | u64 id; |
7f453c24 | 4626 | u64 stream_id; |
a78ac325 PZ |
4627 | } throttle_event = { |
4628 | .header = { | |
cdd6c482 | 4629 | .type = PERF_RECORD_THROTTLE, |
a78ac325 PZ |
4630 | .misc = 0, |
4631 | .size = sizeof(throttle_event), | |
4632 | }, | |
def0a9b2 | 4633 | .time = perf_clock(), |
cdd6c482 IM |
4634 | .id = primary_event_id(event), |
4635 | .stream_id = event->id, | |
a78ac325 PZ |
4636 | }; |
4637 | ||
966ee4d6 | 4638 | if (enable) |
cdd6c482 | 4639 | throttle_event.header.type = PERF_RECORD_UNTHROTTLE; |
966ee4d6 | 4640 | |
c980d109 ACM |
4641 | perf_event_header__init_id(&throttle_event.header, &sample, event); |
4642 | ||
4643 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 4644 | throttle_event.header.size); |
a78ac325 PZ |
4645 | if (ret) |
4646 | return; | |
4647 | ||
4648 | perf_output_put(&handle, throttle_event); | |
c980d109 | 4649 | perf_event__output_id_sample(event, &handle, &sample); |
a78ac325 PZ |
4650 | perf_output_end(&handle); |
4651 | } | |
4652 | ||
f6c7d5fe | 4653 | /* |
cdd6c482 | 4654 | * Generic event overflow handling, sampling. |
f6c7d5fe PZ |
4655 | */ |
4656 | ||
a8b0ca17 | 4657 | static int __perf_event_overflow(struct perf_event *event, |
5622f295 MM |
4658 | int throttle, struct perf_sample_data *data, |
4659 | struct pt_regs *regs) | |
f6c7d5fe | 4660 | { |
cdd6c482 IM |
4661 | int events = atomic_read(&event->event_limit); |
4662 | struct hw_perf_event *hwc = &event->hw; | |
e050e3f0 | 4663 | u64 seq; |
79f14641 PZ |
4664 | int ret = 0; |
4665 | ||
96398826 PZ |
4666 | /* |
4667 | * Non-sampling counters might still use the PMI to fold short | |
4668 | * hardware counters, ignore those. | |
4669 | */ | |
4670 | if (unlikely(!is_sampling_event(event))) | |
4671 | return 0; | |
4672 | ||
e050e3f0 SE |
4673 | seq = __this_cpu_read(perf_throttled_seq); |
4674 | if (seq != hwc->interrupts_seq) { | |
4675 | hwc->interrupts_seq = seq; | |
4676 | hwc->interrupts = 1; | |
4677 | } else { | |
4678 | hwc->interrupts++; | |
4679 | if (unlikely(throttle | |
4680 | && hwc->interrupts >= max_samples_per_tick)) { | |
4681 | __this_cpu_inc(perf_throttled_count); | |
163ec435 PZ |
4682 | hwc->interrupts = MAX_INTERRUPTS; |
4683 | perf_log_throttle(event, 0); | |
a78ac325 PZ |
4684 | ret = 1; |
4685 | } | |
e050e3f0 | 4686 | } |
60db5e09 | 4687 | |
cdd6c482 | 4688 | if (event->attr.freq) { |
def0a9b2 | 4689 | u64 now = perf_clock(); |
abd50713 | 4690 | s64 delta = now - hwc->freq_time_stamp; |
bd2b5b12 | 4691 | |
abd50713 | 4692 | hwc->freq_time_stamp = now; |
bd2b5b12 | 4693 | |
abd50713 | 4694 | if (delta > 0 && delta < 2*TICK_NSEC) |
f39d47ff | 4695 | perf_adjust_period(event, delta, hwc->last_period, true); |
bd2b5b12 PZ |
4696 | } |
4697 | ||
2023b359 PZ |
4698 | /* |
4699 | * XXX event_limit might not quite work as expected on inherited | |
cdd6c482 | 4700 | * events |
2023b359 PZ |
4701 | */ |
4702 | ||
cdd6c482 IM |
4703 | event->pending_kill = POLL_IN; |
4704 | if (events && atomic_dec_and_test(&event->event_limit)) { | |
79f14641 | 4705 | ret = 1; |
cdd6c482 | 4706 | event->pending_kill = POLL_HUP; |
a8b0ca17 PZ |
4707 | event->pending_disable = 1; |
4708 | irq_work_queue(&event->pending); | |
79f14641 PZ |
4709 | } |
4710 | ||
453f19ee | 4711 | if (event->overflow_handler) |
a8b0ca17 | 4712 | event->overflow_handler(event, data, regs); |
453f19ee | 4713 | else |
a8b0ca17 | 4714 | perf_event_output(event, data, regs); |
453f19ee | 4715 | |
f506b3dc | 4716 | if (event->fasync && event->pending_kill) { |
a8b0ca17 PZ |
4717 | event->pending_wakeup = 1; |
4718 | irq_work_queue(&event->pending); | |
f506b3dc PZ |
4719 | } |
4720 | ||
79f14641 | 4721 | return ret; |
f6c7d5fe PZ |
4722 | } |
4723 | ||
a8b0ca17 | 4724 | int perf_event_overflow(struct perf_event *event, |
5622f295 MM |
4725 | struct perf_sample_data *data, |
4726 | struct pt_regs *regs) | |
850bc73f | 4727 | { |
a8b0ca17 | 4728 | return __perf_event_overflow(event, 1, data, regs); |
850bc73f PZ |
4729 | } |
4730 | ||
15dbf27c | 4731 | /* |
cdd6c482 | 4732 | * Generic software event infrastructure |
15dbf27c PZ |
4733 | */ |
4734 | ||
b28ab83c PZ |
4735 | struct swevent_htable { |
4736 | struct swevent_hlist *swevent_hlist; | |
4737 | struct mutex hlist_mutex; | |
4738 | int hlist_refcount; | |
4739 | ||
4740 | /* Recursion avoidance in each contexts */ | |
4741 | int recursion[PERF_NR_CONTEXTS]; | |
4742 | }; | |
4743 | ||
4744 | static DEFINE_PER_CPU(struct swevent_htable, swevent_htable); | |
4745 | ||
7b4b6658 | 4746 | /* |
cdd6c482 IM |
4747 | * We directly increment event->count and keep a second value in |
4748 | * event->hw.period_left to count intervals. This period event | |
7b4b6658 PZ |
4749 | * is kept in the range [-sample_period, 0] so that we can use the |
4750 | * sign as trigger. | |
4751 | */ | |
4752 | ||
cdd6c482 | 4753 | static u64 perf_swevent_set_period(struct perf_event *event) |
15dbf27c | 4754 | { |
cdd6c482 | 4755 | struct hw_perf_event *hwc = &event->hw; |
7b4b6658 PZ |
4756 | u64 period = hwc->last_period; |
4757 | u64 nr, offset; | |
4758 | s64 old, val; | |
4759 | ||
4760 | hwc->last_period = hwc->sample_period; | |
15dbf27c PZ |
4761 | |
4762 | again: | |
e7850595 | 4763 | old = val = local64_read(&hwc->period_left); |
7b4b6658 PZ |
4764 | if (val < 0) |
4765 | return 0; | |
15dbf27c | 4766 | |
7b4b6658 PZ |
4767 | nr = div64_u64(period + val, period); |
4768 | offset = nr * period; | |
4769 | val -= offset; | |
e7850595 | 4770 | if (local64_cmpxchg(&hwc->period_left, old, val) != old) |
7b4b6658 | 4771 | goto again; |
15dbf27c | 4772 | |
7b4b6658 | 4773 | return nr; |
15dbf27c PZ |
4774 | } |
4775 | ||
0cff784a | 4776 | static void perf_swevent_overflow(struct perf_event *event, u64 overflow, |
a8b0ca17 | 4777 | struct perf_sample_data *data, |
5622f295 | 4778 | struct pt_regs *regs) |
15dbf27c | 4779 | { |
cdd6c482 | 4780 | struct hw_perf_event *hwc = &event->hw; |
850bc73f | 4781 | int throttle = 0; |
15dbf27c | 4782 | |
0cff784a PZ |
4783 | if (!overflow) |
4784 | overflow = perf_swevent_set_period(event); | |
15dbf27c | 4785 | |
7b4b6658 PZ |
4786 | if (hwc->interrupts == MAX_INTERRUPTS) |
4787 | return; | |
15dbf27c | 4788 | |
7b4b6658 | 4789 | for (; overflow; overflow--) { |
a8b0ca17 | 4790 | if (__perf_event_overflow(event, throttle, |
5622f295 | 4791 | data, regs)) { |
7b4b6658 PZ |
4792 | /* |
4793 | * We inhibit the overflow from happening when | |
4794 | * hwc->interrupts == MAX_INTERRUPTS. | |
4795 | */ | |
4796 | break; | |
4797 | } | |
cf450a73 | 4798 | throttle = 1; |
7b4b6658 | 4799 | } |
15dbf27c PZ |
4800 | } |
4801 | ||
a4eaf7f1 | 4802 | static void perf_swevent_event(struct perf_event *event, u64 nr, |
a8b0ca17 | 4803 | struct perf_sample_data *data, |
5622f295 | 4804 | struct pt_regs *regs) |
7b4b6658 | 4805 | { |
cdd6c482 | 4806 | struct hw_perf_event *hwc = &event->hw; |
d6d020e9 | 4807 | |
e7850595 | 4808 | local64_add(nr, &event->count); |
d6d020e9 | 4809 | |
0cff784a PZ |
4810 | if (!regs) |
4811 | return; | |
4812 | ||
6c7e550f | 4813 | if (!is_sampling_event(event)) |
7b4b6658 | 4814 | return; |
d6d020e9 | 4815 | |
5d81e5cf AV |
4816 | if ((event->attr.sample_type & PERF_SAMPLE_PERIOD) && !event->attr.freq) { |
4817 | data->period = nr; | |
4818 | return perf_swevent_overflow(event, 1, data, regs); | |
4819 | } else | |
4820 | data->period = event->hw.last_period; | |
4821 | ||
0cff784a | 4822 | if (nr == 1 && hwc->sample_period == 1 && !event->attr.freq) |
a8b0ca17 | 4823 | return perf_swevent_overflow(event, 1, data, regs); |
0cff784a | 4824 | |
e7850595 | 4825 | if (local64_add_negative(nr, &hwc->period_left)) |
7b4b6658 | 4826 | return; |
df1a132b | 4827 | |
a8b0ca17 | 4828 | perf_swevent_overflow(event, 0, data, regs); |
d6d020e9 PZ |
4829 | } |
4830 | ||
f5ffe02e FW |
4831 | static int perf_exclude_event(struct perf_event *event, |
4832 | struct pt_regs *regs) | |
4833 | { | |
a4eaf7f1 | 4834 | if (event->hw.state & PERF_HES_STOPPED) |
91b2f482 | 4835 | return 1; |
a4eaf7f1 | 4836 | |
f5ffe02e FW |
4837 | if (regs) { |
4838 | if (event->attr.exclude_user && user_mode(regs)) | |
4839 | return 1; | |
4840 | ||
4841 | if (event->attr.exclude_kernel && !user_mode(regs)) | |
4842 | return 1; | |
4843 | } | |
4844 | ||
4845 | return 0; | |
4846 | } | |
4847 | ||
cdd6c482 | 4848 | static int perf_swevent_match(struct perf_event *event, |
1c432d89 | 4849 | enum perf_type_id type, |
6fb2915d LZ |
4850 | u32 event_id, |
4851 | struct perf_sample_data *data, | |
4852 | struct pt_regs *regs) | |
15dbf27c | 4853 | { |
cdd6c482 | 4854 | if (event->attr.type != type) |
a21ca2ca | 4855 | return 0; |
f5ffe02e | 4856 | |
cdd6c482 | 4857 | if (event->attr.config != event_id) |
15dbf27c PZ |
4858 | return 0; |
4859 | ||
f5ffe02e FW |
4860 | if (perf_exclude_event(event, regs)) |
4861 | return 0; | |
15dbf27c PZ |
4862 | |
4863 | return 1; | |
4864 | } | |
4865 | ||
76e1d904 FW |
4866 | static inline u64 swevent_hash(u64 type, u32 event_id) |
4867 | { | |
4868 | u64 val = event_id | (type << 32); | |
4869 | ||
4870 | return hash_64(val, SWEVENT_HLIST_BITS); | |
4871 | } | |
4872 | ||
49f135ed FW |
4873 | static inline struct hlist_head * |
4874 | __find_swevent_head(struct swevent_hlist *hlist, u64 type, u32 event_id) | |
76e1d904 | 4875 | { |
49f135ed FW |
4876 | u64 hash = swevent_hash(type, event_id); |
4877 | ||
4878 | return &hlist->heads[hash]; | |
4879 | } | |
76e1d904 | 4880 | |
49f135ed FW |
4881 | /* For the read side: events when they trigger */ |
4882 | static inline struct hlist_head * | |
b28ab83c | 4883 | find_swevent_head_rcu(struct swevent_htable *swhash, u64 type, u32 event_id) |
49f135ed FW |
4884 | { |
4885 | struct swevent_hlist *hlist; | |
76e1d904 | 4886 | |
b28ab83c | 4887 | hlist = rcu_dereference(swhash->swevent_hlist); |
76e1d904 FW |
4888 | if (!hlist) |
4889 | return NULL; | |
4890 | ||
49f135ed FW |
4891 | return __find_swevent_head(hlist, type, event_id); |
4892 | } | |
4893 | ||
4894 | /* For the event head insertion and removal in the hlist */ | |
4895 | static inline struct hlist_head * | |
b28ab83c | 4896 | find_swevent_head(struct swevent_htable *swhash, struct perf_event *event) |
49f135ed FW |
4897 | { |
4898 | struct swevent_hlist *hlist; | |
4899 | u32 event_id = event->attr.config; | |
4900 | u64 type = event->attr.type; | |
4901 | ||
4902 | /* | |
4903 | * Event scheduling is always serialized against hlist allocation | |
4904 | * and release. Which makes the protected version suitable here. | |
4905 | * The context lock guarantees that. | |
4906 | */ | |
b28ab83c | 4907 | hlist = rcu_dereference_protected(swhash->swevent_hlist, |
49f135ed FW |
4908 | lockdep_is_held(&event->ctx->lock)); |
4909 | if (!hlist) | |
4910 | return NULL; | |
4911 | ||
4912 | return __find_swevent_head(hlist, type, event_id); | |
76e1d904 FW |
4913 | } |
4914 | ||
4915 | static void do_perf_sw_event(enum perf_type_id type, u32 event_id, | |
a8b0ca17 | 4916 | u64 nr, |
76e1d904 FW |
4917 | struct perf_sample_data *data, |
4918 | struct pt_regs *regs) | |
15dbf27c | 4919 | { |
b28ab83c | 4920 | struct swevent_htable *swhash = &__get_cpu_var(swevent_htable); |
cdd6c482 | 4921 | struct perf_event *event; |
76e1d904 FW |
4922 | struct hlist_node *node; |
4923 | struct hlist_head *head; | |
15dbf27c | 4924 | |
76e1d904 | 4925 | rcu_read_lock(); |
b28ab83c | 4926 | head = find_swevent_head_rcu(swhash, type, event_id); |
76e1d904 FW |
4927 | if (!head) |
4928 | goto end; | |
4929 | ||
4930 | hlist_for_each_entry_rcu(event, node, head, hlist_entry) { | |
6fb2915d | 4931 | if (perf_swevent_match(event, type, event_id, data, regs)) |
a8b0ca17 | 4932 | perf_swevent_event(event, nr, data, regs); |
15dbf27c | 4933 | } |
76e1d904 FW |
4934 | end: |
4935 | rcu_read_unlock(); | |
15dbf27c PZ |
4936 | } |
4937 | ||
4ed7c92d | 4938 | int perf_swevent_get_recursion_context(void) |
96f6d444 | 4939 | { |
b28ab83c | 4940 | struct swevent_htable *swhash = &__get_cpu_var(swevent_htable); |
96f6d444 | 4941 | |
b28ab83c | 4942 | return get_recursion_context(swhash->recursion); |
96f6d444 | 4943 | } |
645e8cc0 | 4944 | EXPORT_SYMBOL_GPL(perf_swevent_get_recursion_context); |
96f6d444 | 4945 | |
fa9f90be | 4946 | inline void perf_swevent_put_recursion_context(int rctx) |
15dbf27c | 4947 | { |
b28ab83c | 4948 | struct swevent_htable *swhash = &__get_cpu_var(swevent_htable); |
927c7a9e | 4949 | |
b28ab83c | 4950 | put_recursion_context(swhash->recursion, rctx); |
ce71b9df | 4951 | } |
15dbf27c | 4952 | |
a8b0ca17 | 4953 | void __perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) |
b8e83514 | 4954 | { |
a4234bfc | 4955 | struct perf_sample_data data; |
4ed7c92d PZ |
4956 | int rctx; |
4957 | ||
1c024eca | 4958 | preempt_disable_notrace(); |
4ed7c92d PZ |
4959 | rctx = perf_swevent_get_recursion_context(); |
4960 | if (rctx < 0) | |
4961 | return; | |
a4234bfc | 4962 | |
fd0d000b | 4963 | perf_sample_data_init(&data, addr, 0); |
92bf309a | 4964 | |
a8b0ca17 | 4965 | do_perf_sw_event(PERF_TYPE_SOFTWARE, event_id, nr, &data, regs); |
4ed7c92d PZ |
4966 | |
4967 | perf_swevent_put_recursion_context(rctx); | |
1c024eca | 4968 | preempt_enable_notrace(); |
b8e83514 PZ |
4969 | } |
4970 | ||
cdd6c482 | 4971 | static void perf_swevent_read(struct perf_event *event) |
15dbf27c | 4972 | { |
15dbf27c PZ |
4973 | } |
4974 | ||
a4eaf7f1 | 4975 | static int perf_swevent_add(struct perf_event *event, int flags) |
15dbf27c | 4976 | { |
b28ab83c | 4977 | struct swevent_htable *swhash = &__get_cpu_var(swevent_htable); |
cdd6c482 | 4978 | struct hw_perf_event *hwc = &event->hw; |
76e1d904 FW |
4979 | struct hlist_head *head; |
4980 | ||
6c7e550f | 4981 | if (is_sampling_event(event)) { |
7b4b6658 | 4982 | hwc->last_period = hwc->sample_period; |
cdd6c482 | 4983 | perf_swevent_set_period(event); |
7b4b6658 | 4984 | } |
76e1d904 | 4985 | |
a4eaf7f1 PZ |
4986 | hwc->state = !(flags & PERF_EF_START); |
4987 | ||
b28ab83c | 4988 | head = find_swevent_head(swhash, event); |
76e1d904 FW |
4989 | if (WARN_ON_ONCE(!head)) |
4990 | return -EINVAL; | |
4991 | ||
4992 | hlist_add_head_rcu(&event->hlist_entry, head); | |
4993 | ||
15dbf27c PZ |
4994 | return 0; |
4995 | } | |
4996 | ||
a4eaf7f1 | 4997 | static void perf_swevent_del(struct perf_event *event, int flags) |
15dbf27c | 4998 | { |
76e1d904 | 4999 | hlist_del_rcu(&event->hlist_entry); |
15dbf27c PZ |
5000 | } |
5001 | ||
a4eaf7f1 | 5002 | static void perf_swevent_start(struct perf_event *event, int flags) |
5c92d124 | 5003 | { |
a4eaf7f1 | 5004 | event->hw.state = 0; |
d6d020e9 | 5005 | } |
aa9c4c0f | 5006 | |
a4eaf7f1 | 5007 | static void perf_swevent_stop(struct perf_event *event, int flags) |
d6d020e9 | 5008 | { |
a4eaf7f1 | 5009 | event->hw.state = PERF_HES_STOPPED; |
bae43c99 IM |
5010 | } |
5011 | ||
49f135ed FW |
5012 | /* Deref the hlist from the update side */ |
5013 | static inline struct swevent_hlist * | |
b28ab83c | 5014 | swevent_hlist_deref(struct swevent_htable *swhash) |
49f135ed | 5015 | { |
b28ab83c PZ |
5016 | return rcu_dereference_protected(swhash->swevent_hlist, |
5017 | lockdep_is_held(&swhash->hlist_mutex)); | |
49f135ed FW |
5018 | } |
5019 | ||
b28ab83c | 5020 | static void swevent_hlist_release(struct swevent_htable *swhash) |
76e1d904 | 5021 | { |
b28ab83c | 5022 | struct swevent_hlist *hlist = swevent_hlist_deref(swhash); |
76e1d904 | 5023 | |
49f135ed | 5024 | if (!hlist) |
76e1d904 FW |
5025 | return; |
5026 | ||
b28ab83c | 5027 | rcu_assign_pointer(swhash->swevent_hlist, NULL); |
fa4bbc4c | 5028 | kfree_rcu(hlist, rcu_head); |
76e1d904 FW |
5029 | } |
5030 | ||
5031 | static void swevent_hlist_put_cpu(struct perf_event *event, int cpu) | |
5032 | { | |
b28ab83c | 5033 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 | 5034 | |
b28ab83c | 5035 | mutex_lock(&swhash->hlist_mutex); |
76e1d904 | 5036 | |
b28ab83c PZ |
5037 | if (!--swhash->hlist_refcount) |
5038 | swevent_hlist_release(swhash); | |
76e1d904 | 5039 | |
b28ab83c | 5040 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
5041 | } |
5042 | ||
5043 | static void swevent_hlist_put(struct perf_event *event) | |
5044 | { | |
5045 | int cpu; | |
5046 | ||
5047 | if (event->cpu != -1) { | |
5048 | swevent_hlist_put_cpu(event, event->cpu); | |
5049 | return; | |
5050 | } | |
5051 | ||
5052 | for_each_possible_cpu(cpu) | |
5053 | swevent_hlist_put_cpu(event, cpu); | |
5054 | } | |
5055 | ||
5056 | static int swevent_hlist_get_cpu(struct perf_event *event, int cpu) | |
5057 | { | |
b28ab83c | 5058 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 FW |
5059 | int err = 0; |
5060 | ||
b28ab83c | 5061 | mutex_lock(&swhash->hlist_mutex); |
76e1d904 | 5062 | |
b28ab83c | 5063 | if (!swevent_hlist_deref(swhash) && cpu_online(cpu)) { |
76e1d904 FW |
5064 | struct swevent_hlist *hlist; |
5065 | ||
5066 | hlist = kzalloc(sizeof(*hlist), GFP_KERNEL); | |
5067 | if (!hlist) { | |
5068 | err = -ENOMEM; | |
5069 | goto exit; | |
5070 | } | |
b28ab83c | 5071 | rcu_assign_pointer(swhash->swevent_hlist, hlist); |
76e1d904 | 5072 | } |
b28ab83c | 5073 | swhash->hlist_refcount++; |
9ed6060d | 5074 | exit: |
b28ab83c | 5075 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
5076 | |
5077 | return err; | |
5078 | } | |
5079 | ||
5080 | static int swevent_hlist_get(struct perf_event *event) | |
5081 | { | |
5082 | int err; | |
5083 | int cpu, failed_cpu; | |
5084 | ||
5085 | if (event->cpu != -1) | |
5086 | return swevent_hlist_get_cpu(event, event->cpu); | |
5087 | ||
5088 | get_online_cpus(); | |
5089 | for_each_possible_cpu(cpu) { | |
5090 | err = swevent_hlist_get_cpu(event, cpu); | |
5091 | if (err) { | |
5092 | failed_cpu = cpu; | |
5093 | goto fail; | |
5094 | } | |
5095 | } | |
5096 | put_online_cpus(); | |
5097 | ||
5098 | return 0; | |
9ed6060d | 5099 | fail: |
76e1d904 FW |
5100 | for_each_possible_cpu(cpu) { |
5101 | if (cpu == failed_cpu) | |
5102 | break; | |
5103 | swevent_hlist_put_cpu(event, cpu); | |
5104 | } | |
5105 | ||
5106 | put_online_cpus(); | |
5107 | return err; | |
5108 | } | |
5109 | ||
c5905afb | 5110 | struct static_key perf_swevent_enabled[PERF_COUNT_SW_MAX]; |
95476b64 | 5111 | |
b0a873eb PZ |
5112 | static void sw_perf_event_destroy(struct perf_event *event) |
5113 | { | |
5114 | u64 event_id = event->attr.config; | |
95476b64 | 5115 | |
b0a873eb PZ |
5116 | WARN_ON(event->parent); |
5117 | ||
c5905afb | 5118 | static_key_slow_dec(&perf_swevent_enabled[event_id]); |
b0a873eb PZ |
5119 | swevent_hlist_put(event); |
5120 | } | |
5121 | ||
5122 | static int perf_swevent_init(struct perf_event *event) | |
5123 | { | |
5124 | int event_id = event->attr.config; | |
5125 | ||
5126 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
5127 | return -ENOENT; | |
5128 | ||
2481c5fa SE |
5129 | /* |
5130 | * no branch sampling for software events | |
5131 | */ | |
5132 | if (has_branch_stack(event)) | |
5133 | return -EOPNOTSUPP; | |
5134 | ||
b0a873eb PZ |
5135 | switch (event_id) { |
5136 | case PERF_COUNT_SW_CPU_CLOCK: | |
5137 | case PERF_COUNT_SW_TASK_CLOCK: | |
5138 | return -ENOENT; | |
5139 | ||
5140 | default: | |
5141 | break; | |
5142 | } | |
5143 | ||
ce677831 | 5144 | if (event_id >= PERF_COUNT_SW_MAX) |
b0a873eb PZ |
5145 | return -ENOENT; |
5146 | ||
5147 | if (!event->parent) { | |
5148 | int err; | |
5149 | ||
5150 | err = swevent_hlist_get(event); | |
5151 | if (err) | |
5152 | return err; | |
5153 | ||
c5905afb | 5154 | static_key_slow_inc(&perf_swevent_enabled[event_id]); |
b0a873eb PZ |
5155 | event->destroy = sw_perf_event_destroy; |
5156 | } | |
5157 | ||
5158 | return 0; | |
5159 | } | |
5160 | ||
35edc2a5 PZ |
5161 | static int perf_swevent_event_idx(struct perf_event *event) |
5162 | { | |
5163 | return 0; | |
5164 | } | |
5165 | ||
b0a873eb | 5166 | static struct pmu perf_swevent = { |
89a1e187 | 5167 | .task_ctx_nr = perf_sw_context, |
95476b64 | 5168 | |
b0a873eb | 5169 | .event_init = perf_swevent_init, |
a4eaf7f1 PZ |
5170 | .add = perf_swevent_add, |
5171 | .del = perf_swevent_del, | |
5172 | .start = perf_swevent_start, | |
5173 | .stop = perf_swevent_stop, | |
1c024eca | 5174 | .read = perf_swevent_read, |
35edc2a5 PZ |
5175 | |
5176 | .event_idx = perf_swevent_event_idx, | |
1c024eca PZ |
5177 | }; |
5178 | ||
b0a873eb PZ |
5179 | #ifdef CONFIG_EVENT_TRACING |
5180 | ||
1c024eca PZ |
5181 | static int perf_tp_filter_match(struct perf_event *event, |
5182 | struct perf_sample_data *data) | |
5183 | { | |
5184 | void *record = data->raw->data; | |
5185 | ||
5186 | if (likely(!event->filter) || filter_match_preds(event->filter, record)) | |
5187 | return 1; | |
5188 | return 0; | |
5189 | } | |
5190 | ||
5191 | static int perf_tp_event_match(struct perf_event *event, | |
5192 | struct perf_sample_data *data, | |
5193 | struct pt_regs *regs) | |
5194 | { | |
a0f7d0f7 FW |
5195 | if (event->hw.state & PERF_HES_STOPPED) |
5196 | return 0; | |
580d607c PZ |
5197 | /* |
5198 | * All tracepoints are from kernel-space. | |
5199 | */ | |
5200 | if (event->attr.exclude_kernel) | |
1c024eca PZ |
5201 | return 0; |
5202 | ||
5203 | if (!perf_tp_filter_match(event, data)) | |
5204 | return 0; | |
5205 | ||
5206 | return 1; | |
5207 | } | |
5208 | ||
5209 | void perf_tp_event(u64 addr, u64 count, void *record, int entry_size, | |
ecc55f84 | 5210 | struct pt_regs *regs, struct hlist_head *head, int rctx) |
95476b64 FW |
5211 | { |
5212 | struct perf_sample_data data; | |
1c024eca PZ |
5213 | struct perf_event *event; |
5214 | struct hlist_node *node; | |
5215 | ||
95476b64 FW |
5216 | struct perf_raw_record raw = { |
5217 | .size = entry_size, | |
5218 | .data = record, | |
5219 | }; | |
5220 | ||
fd0d000b | 5221 | perf_sample_data_init(&data, addr, 0); |
95476b64 FW |
5222 | data.raw = &raw; |
5223 | ||
1c024eca PZ |
5224 | hlist_for_each_entry_rcu(event, node, head, hlist_entry) { |
5225 | if (perf_tp_event_match(event, &data, regs)) | |
a8b0ca17 | 5226 | perf_swevent_event(event, count, &data, regs); |
4f41c013 | 5227 | } |
ecc55f84 PZ |
5228 | |
5229 | perf_swevent_put_recursion_context(rctx); | |
95476b64 FW |
5230 | } |
5231 | EXPORT_SYMBOL_GPL(perf_tp_event); | |
5232 | ||
cdd6c482 | 5233 | static void tp_perf_event_destroy(struct perf_event *event) |
e077df4f | 5234 | { |
1c024eca | 5235 | perf_trace_destroy(event); |
e077df4f PZ |
5236 | } |
5237 | ||
b0a873eb | 5238 | static int perf_tp_event_init(struct perf_event *event) |
e077df4f | 5239 | { |
76e1d904 FW |
5240 | int err; |
5241 | ||
b0a873eb PZ |
5242 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
5243 | return -ENOENT; | |
5244 | ||
2481c5fa SE |
5245 | /* |
5246 | * no branch sampling for tracepoint events | |
5247 | */ | |
5248 | if (has_branch_stack(event)) | |
5249 | return -EOPNOTSUPP; | |
5250 | ||
1c024eca PZ |
5251 | err = perf_trace_init(event); |
5252 | if (err) | |
b0a873eb | 5253 | return err; |
e077df4f | 5254 | |
cdd6c482 | 5255 | event->destroy = tp_perf_event_destroy; |
e077df4f | 5256 | |
b0a873eb PZ |
5257 | return 0; |
5258 | } | |
5259 | ||
5260 | static struct pmu perf_tracepoint = { | |
89a1e187 PZ |
5261 | .task_ctx_nr = perf_sw_context, |
5262 | ||
b0a873eb | 5263 | .event_init = perf_tp_event_init, |
a4eaf7f1 PZ |
5264 | .add = perf_trace_add, |
5265 | .del = perf_trace_del, | |
5266 | .start = perf_swevent_start, | |
5267 | .stop = perf_swevent_stop, | |
b0a873eb | 5268 | .read = perf_swevent_read, |
35edc2a5 PZ |
5269 | |
5270 | .event_idx = perf_swevent_event_idx, | |
b0a873eb PZ |
5271 | }; |
5272 | ||
5273 | static inline void perf_tp_register(void) | |
5274 | { | |
2e80a82a | 5275 | perf_pmu_register(&perf_tracepoint, "tracepoint", PERF_TYPE_TRACEPOINT); |
e077df4f | 5276 | } |
6fb2915d LZ |
5277 | |
5278 | static int perf_event_set_filter(struct perf_event *event, void __user *arg) | |
5279 | { | |
5280 | char *filter_str; | |
5281 | int ret; | |
5282 | ||
5283 | if (event->attr.type != PERF_TYPE_TRACEPOINT) | |
5284 | return -EINVAL; | |
5285 | ||
5286 | filter_str = strndup_user(arg, PAGE_SIZE); | |
5287 | if (IS_ERR(filter_str)) | |
5288 | return PTR_ERR(filter_str); | |
5289 | ||
5290 | ret = ftrace_profile_set_filter(event, event->attr.config, filter_str); | |
5291 | ||
5292 | kfree(filter_str); | |
5293 | return ret; | |
5294 | } | |
5295 | ||
5296 | static void perf_event_free_filter(struct perf_event *event) | |
5297 | { | |
5298 | ftrace_profile_free_filter(event); | |
5299 | } | |
5300 | ||
e077df4f | 5301 | #else |
6fb2915d | 5302 | |
b0a873eb | 5303 | static inline void perf_tp_register(void) |
e077df4f | 5304 | { |
e077df4f | 5305 | } |
6fb2915d LZ |
5306 | |
5307 | static int perf_event_set_filter(struct perf_event *event, void __user *arg) | |
5308 | { | |
5309 | return -ENOENT; | |
5310 | } | |
5311 | ||
5312 | static void perf_event_free_filter(struct perf_event *event) | |
5313 | { | |
5314 | } | |
5315 | ||
07b139c8 | 5316 | #endif /* CONFIG_EVENT_TRACING */ |
e077df4f | 5317 | |
24f1e32c | 5318 | #ifdef CONFIG_HAVE_HW_BREAKPOINT |
f5ffe02e | 5319 | void perf_bp_event(struct perf_event *bp, void *data) |
24f1e32c | 5320 | { |
f5ffe02e FW |
5321 | struct perf_sample_data sample; |
5322 | struct pt_regs *regs = data; | |
5323 | ||
fd0d000b | 5324 | perf_sample_data_init(&sample, bp->attr.bp_addr, 0); |
f5ffe02e | 5325 | |
a4eaf7f1 | 5326 | if (!bp->hw.state && !perf_exclude_event(bp, regs)) |
a8b0ca17 | 5327 | perf_swevent_event(bp, 1, &sample, regs); |
24f1e32c FW |
5328 | } |
5329 | #endif | |
5330 | ||
b0a873eb PZ |
5331 | /* |
5332 | * hrtimer based swevent callback | |
5333 | */ | |
f29ac756 | 5334 | |
b0a873eb | 5335 | static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer) |
f29ac756 | 5336 | { |
b0a873eb PZ |
5337 | enum hrtimer_restart ret = HRTIMER_RESTART; |
5338 | struct perf_sample_data data; | |
5339 | struct pt_regs *regs; | |
5340 | struct perf_event *event; | |
5341 | u64 period; | |
f29ac756 | 5342 | |
b0a873eb | 5343 | event = container_of(hrtimer, struct perf_event, hw.hrtimer); |
ba3dd36c PZ |
5344 | |
5345 | if (event->state != PERF_EVENT_STATE_ACTIVE) | |
5346 | return HRTIMER_NORESTART; | |
5347 | ||
b0a873eb | 5348 | event->pmu->read(event); |
f344011c | 5349 | |
fd0d000b | 5350 | perf_sample_data_init(&data, 0, event->hw.last_period); |
b0a873eb PZ |
5351 | regs = get_irq_regs(); |
5352 | ||
5353 | if (regs && !perf_exclude_event(event, regs)) { | |
77aeeebd | 5354 | if (!(event->attr.exclude_idle && is_idle_task(current))) |
33b07b8b | 5355 | if (__perf_event_overflow(event, 1, &data, regs)) |
b0a873eb PZ |
5356 | ret = HRTIMER_NORESTART; |
5357 | } | |
24f1e32c | 5358 | |
b0a873eb PZ |
5359 | period = max_t(u64, 10000, event->hw.sample_period); |
5360 | hrtimer_forward_now(hrtimer, ns_to_ktime(period)); | |
24f1e32c | 5361 | |
b0a873eb | 5362 | return ret; |
f29ac756 PZ |
5363 | } |
5364 | ||
b0a873eb | 5365 | static void perf_swevent_start_hrtimer(struct perf_event *event) |
5c92d124 | 5366 | { |
b0a873eb | 5367 | struct hw_perf_event *hwc = &event->hw; |
5d508e82 FBH |
5368 | s64 period; |
5369 | ||
5370 | if (!is_sampling_event(event)) | |
5371 | return; | |
f5ffe02e | 5372 | |
5d508e82 FBH |
5373 | period = local64_read(&hwc->period_left); |
5374 | if (period) { | |
5375 | if (period < 0) | |
5376 | period = 10000; | |
fa407f35 | 5377 | |
5d508e82 FBH |
5378 | local64_set(&hwc->period_left, 0); |
5379 | } else { | |
5380 | period = max_t(u64, 10000, hwc->sample_period); | |
5381 | } | |
5382 | __hrtimer_start_range_ns(&hwc->hrtimer, | |
b0a873eb | 5383 | ns_to_ktime(period), 0, |
b5ab4cd5 | 5384 | HRTIMER_MODE_REL_PINNED, 0); |
24f1e32c | 5385 | } |
b0a873eb PZ |
5386 | |
5387 | static void perf_swevent_cancel_hrtimer(struct perf_event *event) | |
24f1e32c | 5388 | { |
b0a873eb PZ |
5389 | struct hw_perf_event *hwc = &event->hw; |
5390 | ||
6c7e550f | 5391 | if (is_sampling_event(event)) { |
b0a873eb | 5392 | ktime_t remaining = hrtimer_get_remaining(&hwc->hrtimer); |
fa407f35 | 5393 | local64_set(&hwc->period_left, ktime_to_ns(remaining)); |
b0a873eb PZ |
5394 | |
5395 | hrtimer_cancel(&hwc->hrtimer); | |
5396 | } | |
24f1e32c FW |
5397 | } |
5398 | ||
ba3dd36c PZ |
5399 | static void perf_swevent_init_hrtimer(struct perf_event *event) |
5400 | { | |
5401 | struct hw_perf_event *hwc = &event->hw; | |
5402 | ||
5403 | if (!is_sampling_event(event)) | |
5404 | return; | |
5405 | ||
5406 | hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); | |
5407 | hwc->hrtimer.function = perf_swevent_hrtimer; | |
5408 | ||
5409 | /* | |
5410 | * Since hrtimers have a fixed rate, we can do a static freq->period | |
5411 | * mapping and avoid the whole period adjust feedback stuff. | |
5412 | */ | |
5413 | if (event->attr.freq) { | |
5414 | long freq = event->attr.sample_freq; | |
5415 | ||
5416 | event->attr.sample_period = NSEC_PER_SEC / freq; | |
5417 | hwc->sample_period = event->attr.sample_period; | |
5418 | local64_set(&hwc->period_left, hwc->sample_period); | |
5419 | event->attr.freq = 0; | |
5420 | } | |
5421 | } | |
5422 | ||
b0a873eb PZ |
5423 | /* |
5424 | * Software event: cpu wall time clock | |
5425 | */ | |
5426 | ||
5427 | static void cpu_clock_event_update(struct perf_event *event) | |
24f1e32c | 5428 | { |
b0a873eb PZ |
5429 | s64 prev; |
5430 | u64 now; | |
5431 | ||
a4eaf7f1 | 5432 | now = local_clock(); |
b0a873eb PZ |
5433 | prev = local64_xchg(&event->hw.prev_count, now); |
5434 | local64_add(now - prev, &event->count); | |
24f1e32c | 5435 | } |
24f1e32c | 5436 | |
a4eaf7f1 | 5437 | static void cpu_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 5438 | { |
a4eaf7f1 | 5439 | local64_set(&event->hw.prev_count, local_clock()); |
b0a873eb | 5440 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
5441 | } |
5442 | ||
a4eaf7f1 | 5443 | static void cpu_clock_event_stop(struct perf_event *event, int flags) |
f29ac756 | 5444 | { |
b0a873eb PZ |
5445 | perf_swevent_cancel_hrtimer(event); |
5446 | cpu_clock_event_update(event); | |
5447 | } | |
f29ac756 | 5448 | |
a4eaf7f1 PZ |
5449 | static int cpu_clock_event_add(struct perf_event *event, int flags) |
5450 | { | |
5451 | if (flags & PERF_EF_START) | |
5452 | cpu_clock_event_start(event, flags); | |
5453 | ||
5454 | return 0; | |
5455 | } | |
5456 | ||
5457 | static void cpu_clock_event_del(struct perf_event *event, int flags) | |
5458 | { | |
5459 | cpu_clock_event_stop(event, flags); | |
5460 | } | |
5461 | ||
b0a873eb PZ |
5462 | static void cpu_clock_event_read(struct perf_event *event) |
5463 | { | |
5464 | cpu_clock_event_update(event); | |
5465 | } | |
f344011c | 5466 | |
b0a873eb PZ |
5467 | static int cpu_clock_event_init(struct perf_event *event) |
5468 | { | |
5469 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
5470 | return -ENOENT; | |
5471 | ||
5472 | if (event->attr.config != PERF_COUNT_SW_CPU_CLOCK) | |
5473 | return -ENOENT; | |
5474 | ||
2481c5fa SE |
5475 | /* |
5476 | * no branch sampling for software events | |
5477 | */ | |
5478 | if (has_branch_stack(event)) | |
5479 | return -EOPNOTSUPP; | |
5480 | ||
ba3dd36c PZ |
5481 | perf_swevent_init_hrtimer(event); |
5482 | ||
b0a873eb | 5483 | return 0; |
f29ac756 PZ |
5484 | } |
5485 | ||
b0a873eb | 5486 | static struct pmu perf_cpu_clock = { |
89a1e187 PZ |
5487 | .task_ctx_nr = perf_sw_context, |
5488 | ||
b0a873eb | 5489 | .event_init = cpu_clock_event_init, |
a4eaf7f1 PZ |
5490 | .add = cpu_clock_event_add, |
5491 | .del = cpu_clock_event_del, | |
5492 | .start = cpu_clock_event_start, | |
5493 | .stop = cpu_clock_event_stop, | |
b0a873eb | 5494 | .read = cpu_clock_event_read, |
35edc2a5 PZ |
5495 | |
5496 | .event_idx = perf_swevent_event_idx, | |
b0a873eb PZ |
5497 | }; |
5498 | ||
5499 | /* | |
5500 | * Software event: task time clock | |
5501 | */ | |
5502 | ||
5503 | static void task_clock_event_update(struct perf_event *event, u64 now) | |
5c92d124 | 5504 | { |
b0a873eb PZ |
5505 | u64 prev; |
5506 | s64 delta; | |
5c92d124 | 5507 | |
b0a873eb PZ |
5508 | prev = local64_xchg(&event->hw.prev_count, now); |
5509 | delta = now - prev; | |
5510 | local64_add(delta, &event->count); | |
5511 | } | |
5c92d124 | 5512 | |
a4eaf7f1 | 5513 | static void task_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 5514 | { |
a4eaf7f1 | 5515 | local64_set(&event->hw.prev_count, event->ctx->time); |
b0a873eb | 5516 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
5517 | } |
5518 | ||
a4eaf7f1 | 5519 | static void task_clock_event_stop(struct perf_event *event, int flags) |
b0a873eb PZ |
5520 | { |
5521 | perf_swevent_cancel_hrtimer(event); | |
5522 | task_clock_event_update(event, event->ctx->time); | |
a4eaf7f1 PZ |
5523 | } |
5524 | ||
5525 | static int task_clock_event_add(struct perf_event *event, int flags) | |
5526 | { | |
5527 | if (flags & PERF_EF_START) | |
5528 | task_clock_event_start(event, flags); | |
b0a873eb | 5529 | |
a4eaf7f1 PZ |
5530 | return 0; |
5531 | } | |
5532 | ||
5533 | static void task_clock_event_del(struct perf_event *event, int flags) | |
5534 | { | |
5535 | task_clock_event_stop(event, PERF_EF_UPDATE); | |
b0a873eb PZ |
5536 | } |
5537 | ||
5538 | static void task_clock_event_read(struct perf_event *event) | |
5539 | { | |
768a06e2 PZ |
5540 | u64 now = perf_clock(); |
5541 | u64 delta = now - event->ctx->timestamp; | |
5542 | u64 time = event->ctx->time + delta; | |
b0a873eb PZ |
5543 | |
5544 | task_clock_event_update(event, time); | |
5545 | } | |
5546 | ||
5547 | static int task_clock_event_init(struct perf_event *event) | |
6fb2915d | 5548 | { |
b0a873eb PZ |
5549 | if (event->attr.type != PERF_TYPE_SOFTWARE) |
5550 | return -ENOENT; | |
5551 | ||
5552 | if (event->attr.config != PERF_COUNT_SW_TASK_CLOCK) | |
5553 | return -ENOENT; | |
5554 | ||
2481c5fa SE |
5555 | /* |
5556 | * no branch sampling for software events | |
5557 | */ | |
5558 | if (has_branch_stack(event)) | |
5559 | return -EOPNOTSUPP; | |
5560 | ||
ba3dd36c PZ |
5561 | perf_swevent_init_hrtimer(event); |
5562 | ||
b0a873eb | 5563 | return 0; |
6fb2915d LZ |
5564 | } |
5565 | ||
b0a873eb | 5566 | static struct pmu perf_task_clock = { |
89a1e187 PZ |
5567 | .task_ctx_nr = perf_sw_context, |
5568 | ||
b0a873eb | 5569 | .event_init = task_clock_event_init, |
a4eaf7f1 PZ |
5570 | .add = task_clock_event_add, |
5571 | .del = task_clock_event_del, | |
5572 | .start = task_clock_event_start, | |
5573 | .stop = task_clock_event_stop, | |
b0a873eb | 5574 | .read = task_clock_event_read, |
35edc2a5 PZ |
5575 | |
5576 | .event_idx = perf_swevent_event_idx, | |
b0a873eb | 5577 | }; |
6fb2915d | 5578 | |
ad5133b7 | 5579 | static void perf_pmu_nop_void(struct pmu *pmu) |
e077df4f | 5580 | { |
e077df4f | 5581 | } |
6fb2915d | 5582 | |
ad5133b7 | 5583 | static int perf_pmu_nop_int(struct pmu *pmu) |
6fb2915d | 5584 | { |
ad5133b7 | 5585 | return 0; |
6fb2915d LZ |
5586 | } |
5587 | ||
ad5133b7 | 5588 | static void perf_pmu_start_txn(struct pmu *pmu) |
6fb2915d | 5589 | { |
ad5133b7 | 5590 | perf_pmu_disable(pmu); |
6fb2915d LZ |
5591 | } |
5592 | ||
ad5133b7 PZ |
5593 | static int perf_pmu_commit_txn(struct pmu *pmu) |
5594 | { | |
5595 | perf_pmu_enable(pmu); | |
5596 | return 0; | |
5597 | } | |
e077df4f | 5598 | |
ad5133b7 | 5599 | static void perf_pmu_cancel_txn(struct pmu *pmu) |
24f1e32c | 5600 | { |
ad5133b7 | 5601 | perf_pmu_enable(pmu); |
24f1e32c FW |
5602 | } |
5603 | ||
35edc2a5 PZ |
5604 | static int perf_event_idx_default(struct perf_event *event) |
5605 | { | |
5606 | return event->hw.idx + 1; | |
5607 | } | |
5608 | ||
8dc85d54 PZ |
5609 | /* |
5610 | * Ensures all contexts with the same task_ctx_nr have the same | |
5611 | * pmu_cpu_context too. | |
5612 | */ | |
5613 | static void *find_pmu_context(int ctxn) | |
24f1e32c | 5614 | { |
8dc85d54 | 5615 | struct pmu *pmu; |
b326e956 | 5616 | |
8dc85d54 PZ |
5617 | if (ctxn < 0) |
5618 | return NULL; | |
24f1e32c | 5619 | |
8dc85d54 PZ |
5620 | list_for_each_entry(pmu, &pmus, entry) { |
5621 | if (pmu->task_ctx_nr == ctxn) | |
5622 | return pmu->pmu_cpu_context; | |
5623 | } | |
24f1e32c | 5624 | |
8dc85d54 | 5625 | return NULL; |
24f1e32c FW |
5626 | } |
5627 | ||
51676957 | 5628 | static void update_pmu_context(struct pmu *pmu, struct pmu *old_pmu) |
24f1e32c | 5629 | { |
51676957 PZ |
5630 | int cpu; |
5631 | ||
5632 | for_each_possible_cpu(cpu) { | |
5633 | struct perf_cpu_context *cpuctx; | |
5634 | ||
5635 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
5636 | ||
5637 | if (cpuctx->active_pmu == old_pmu) | |
5638 | cpuctx->active_pmu = pmu; | |
5639 | } | |
5640 | } | |
5641 | ||
5642 | static void free_pmu_context(struct pmu *pmu) | |
5643 | { | |
5644 | struct pmu *i; | |
f5ffe02e | 5645 | |
8dc85d54 | 5646 | mutex_lock(&pmus_lock); |
0475f9ea | 5647 | /* |
8dc85d54 | 5648 | * Like a real lame refcount. |
0475f9ea | 5649 | */ |
51676957 PZ |
5650 | list_for_each_entry(i, &pmus, entry) { |
5651 | if (i->pmu_cpu_context == pmu->pmu_cpu_context) { | |
5652 | update_pmu_context(i, pmu); | |
8dc85d54 | 5653 | goto out; |
51676957 | 5654 | } |
8dc85d54 | 5655 | } |
d6d020e9 | 5656 | |
51676957 | 5657 | free_percpu(pmu->pmu_cpu_context); |
8dc85d54 PZ |
5658 | out: |
5659 | mutex_unlock(&pmus_lock); | |
24f1e32c | 5660 | } |
2e80a82a | 5661 | static struct idr pmu_idr; |
d6d020e9 | 5662 | |
abe43400 PZ |
5663 | static ssize_t |
5664 | type_show(struct device *dev, struct device_attribute *attr, char *page) | |
5665 | { | |
5666 | struct pmu *pmu = dev_get_drvdata(dev); | |
5667 | ||
5668 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->type); | |
5669 | } | |
5670 | ||
5671 | static struct device_attribute pmu_dev_attrs[] = { | |
5672 | __ATTR_RO(type), | |
5673 | __ATTR_NULL, | |
5674 | }; | |
5675 | ||
5676 | static int pmu_bus_running; | |
5677 | static struct bus_type pmu_bus = { | |
5678 | .name = "event_source", | |
5679 | .dev_attrs = pmu_dev_attrs, | |
5680 | }; | |
5681 | ||
5682 | static void pmu_dev_release(struct device *dev) | |
5683 | { | |
5684 | kfree(dev); | |
5685 | } | |
5686 | ||
5687 | static int pmu_dev_alloc(struct pmu *pmu) | |
5688 | { | |
5689 | int ret = -ENOMEM; | |
5690 | ||
5691 | pmu->dev = kzalloc(sizeof(struct device), GFP_KERNEL); | |
5692 | if (!pmu->dev) | |
5693 | goto out; | |
5694 | ||
0c9d42ed | 5695 | pmu->dev->groups = pmu->attr_groups; |
abe43400 PZ |
5696 | device_initialize(pmu->dev); |
5697 | ret = dev_set_name(pmu->dev, "%s", pmu->name); | |
5698 | if (ret) | |
5699 | goto free_dev; | |
5700 | ||
5701 | dev_set_drvdata(pmu->dev, pmu); | |
5702 | pmu->dev->bus = &pmu_bus; | |
5703 | pmu->dev->release = pmu_dev_release; | |
5704 | ret = device_add(pmu->dev); | |
5705 | if (ret) | |
5706 | goto free_dev; | |
5707 | ||
5708 | out: | |
5709 | return ret; | |
5710 | ||
5711 | free_dev: | |
5712 | put_device(pmu->dev); | |
5713 | goto out; | |
5714 | } | |
5715 | ||
547e9fd7 | 5716 | static struct lock_class_key cpuctx_mutex; |
facc4307 | 5717 | static struct lock_class_key cpuctx_lock; |
547e9fd7 | 5718 | |
2e80a82a | 5719 | int perf_pmu_register(struct pmu *pmu, char *name, int type) |
24f1e32c | 5720 | { |
108b02cf | 5721 | int cpu, ret; |
24f1e32c | 5722 | |
b0a873eb | 5723 | mutex_lock(&pmus_lock); |
33696fc0 PZ |
5724 | ret = -ENOMEM; |
5725 | pmu->pmu_disable_count = alloc_percpu(int); | |
5726 | if (!pmu->pmu_disable_count) | |
5727 | goto unlock; | |
f29ac756 | 5728 | |
2e80a82a PZ |
5729 | pmu->type = -1; |
5730 | if (!name) | |
5731 | goto skip_type; | |
5732 | pmu->name = name; | |
5733 | ||
5734 | if (type < 0) { | |
5735 | int err = idr_pre_get(&pmu_idr, GFP_KERNEL); | |
5736 | if (!err) | |
5737 | goto free_pdc; | |
5738 | ||
5739 | err = idr_get_new_above(&pmu_idr, pmu, PERF_TYPE_MAX, &type); | |
5740 | if (err) { | |
5741 | ret = err; | |
5742 | goto free_pdc; | |
5743 | } | |
5744 | } | |
5745 | pmu->type = type; | |
5746 | ||
abe43400 PZ |
5747 | if (pmu_bus_running) { |
5748 | ret = pmu_dev_alloc(pmu); | |
5749 | if (ret) | |
5750 | goto free_idr; | |
5751 | } | |
5752 | ||
2e80a82a | 5753 | skip_type: |
8dc85d54 PZ |
5754 | pmu->pmu_cpu_context = find_pmu_context(pmu->task_ctx_nr); |
5755 | if (pmu->pmu_cpu_context) | |
5756 | goto got_cpu_context; | |
f29ac756 | 5757 | |
108b02cf PZ |
5758 | pmu->pmu_cpu_context = alloc_percpu(struct perf_cpu_context); |
5759 | if (!pmu->pmu_cpu_context) | |
abe43400 | 5760 | goto free_dev; |
f344011c | 5761 | |
108b02cf PZ |
5762 | for_each_possible_cpu(cpu) { |
5763 | struct perf_cpu_context *cpuctx; | |
5764 | ||
5765 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
eb184479 | 5766 | __perf_event_init_context(&cpuctx->ctx); |
547e9fd7 | 5767 | lockdep_set_class(&cpuctx->ctx.mutex, &cpuctx_mutex); |
facc4307 | 5768 | lockdep_set_class(&cpuctx->ctx.lock, &cpuctx_lock); |
b04243ef | 5769 | cpuctx->ctx.type = cpu_context; |
108b02cf | 5770 | cpuctx->ctx.pmu = pmu; |
e9d2b064 PZ |
5771 | cpuctx->jiffies_interval = 1; |
5772 | INIT_LIST_HEAD(&cpuctx->rotation_list); | |
51676957 | 5773 | cpuctx->active_pmu = pmu; |
108b02cf | 5774 | } |
76e1d904 | 5775 | |
8dc85d54 | 5776 | got_cpu_context: |
ad5133b7 PZ |
5777 | if (!pmu->start_txn) { |
5778 | if (pmu->pmu_enable) { | |
5779 | /* | |
5780 | * If we have pmu_enable/pmu_disable calls, install | |
5781 | * transaction stubs that use that to try and batch | |
5782 | * hardware accesses. | |
5783 | */ | |
5784 | pmu->start_txn = perf_pmu_start_txn; | |
5785 | pmu->commit_txn = perf_pmu_commit_txn; | |
5786 | pmu->cancel_txn = perf_pmu_cancel_txn; | |
5787 | } else { | |
5788 | pmu->start_txn = perf_pmu_nop_void; | |
5789 | pmu->commit_txn = perf_pmu_nop_int; | |
5790 | pmu->cancel_txn = perf_pmu_nop_void; | |
f344011c | 5791 | } |
5c92d124 | 5792 | } |
15dbf27c | 5793 | |
ad5133b7 PZ |
5794 | if (!pmu->pmu_enable) { |
5795 | pmu->pmu_enable = perf_pmu_nop_void; | |
5796 | pmu->pmu_disable = perf_pmu_nop_void; | |
5797 | } | |
5798 | ||
35edc2a5 PZ |
5799 | if (!pmu->event_idx) |
5800 | pmu->event_idx = perf_event_idx_default; | |
5801 | ||
b0a873eb | 5802 | list_add_rcu(&pmu->entry, &pmus); |
33696fc0 PZ |
5803 | ret = 0; |
5804 | unlock: | |
b0a873eb PZ |
5805 | mutex_unlock(&pmus_lock); |
5806 | ||
33696fc0 | 5807 | return ret; |
108b02cf | 5808 | |
abe43400 PZ |
5809 | free_dev: |
5810 | device_del(pmu->dev); | |
5811 | put_device(pmu->dev); | |
5812 | ||
2e80a82a PZ |
5813 | free_idr: |
5814 | if (pmu->type >= PERF_TYPE_MAX) | |
5815 | idr_remove(&pmu_idr, pmu->type); | |
5816 | ||
108b02cf PZ |
5817 | free_pdc: |
5818 | free_percpu(pmu->pmu_disable_count); | |
5819 | goto unlock; | |
f29ac756 PZ |
5820 | } |
5821 | ||
b0a873eb | 5822 | void perf_pmu_unregister(struct pmu *pmu) |
5c92d124 | 5823 | { |
b0a873eb PZ |
5824 | mutex_lock(&pmus_lock); |
5825 | list_del_rcu(&pmu->entry); | |
5826 | mutex_unlock(&pmus_lock); | |
5c92d124 | 5827 | |
0475f9ea | 5828 | /* |
cde8e884 PZ |
5829 | * We dereference the pmu list under both SRCU and regular RCU, so |
5830 | * synchronize against both of those. | |
0475f9ea | 5831 | */ |
b0a873eb | 5832 | synchronize_srcu(&pmus_srcu); |
cde8e884 | 5833 | synchronize_rcu(); |
d6d020e9 | 5834 | |
33696fc0 | 5835 | free_percpu(pmu->pmu_disable_count); |
2e80a82a PZ |
5836 | if (pmu->type >= PERF_TYPE_MAX) |
5837 | idr_remove(&pmu_idr, pmu->type); | |
abe43400 PZ |
5838 | device_del(pmu->dev); |
5839 | put_device(pmu->dev); | |
51676957 | 5840 | free_pmu_context(pmu); |
b0a873eb | 5841 | } |
d6d020e9 | 5842 | |
b0a873eb PZ |
5843 | struct pmu *perf_init_event(struct perf_event *event) |
5844 | { | |
5845 | struct pmu *pmu = NULL; | |
5846 | int idx; | |
940c5b29 | 5847 | int ret; |
b0a873eb PZ |
5848 | |
5849 | idx = srcu_read_lock(&pmus_srcu); | |
2e80a82a PZ |
5850 | |
5851 | rcu_read_lock(); | |
5852 | pmu = idr_find(&pmu_idr, event->attr.type); | |
5853 | rcu_read_unlock(); | |
940c5b29 | 5854 | if (pmu) { |
7e5b2a01 | 5855 | event->pmu = pmu; |
940c5b29 LM |
5856 | ret = pmu->event_init(event); |
5857 | if (ret) | |
5858 | pmu = ERR_PTR(ret); | |
2e80a82a | 5859 | goto unlock; |
940c5b29 | 5860 | } |
2e80a82a | 5861 | |
b0a873eb | 5862 | list_for_each_entry_rcu(pmu, &pmus, entry) { |
7e5b2a01 | 5863 | event->pmu = pmu; |
940c5b29 | 5864 | ret = pmu->event_init(event); |
b0a873eb | 5865 | if (!ret) |
e5f4d339 | 5866 | goto unlock; |
76e1d904 | 5867 | |
b0a873eb PZ |
5868 | if (ret != -ENOENT) { |
5869 | pmu = ERR_PTR(ret); | |
e5f4d339 | 5870 | goto unlock; |
f344011c | 5871 | } |
5c92d124 | 5872 | } |
e5f4d339 PZ |
5873 | pmu = ERR_PTR(-ENOENT); |
5874 | unlock: | |
b0a873eb | 5875 | srcu_read_unlock(&pmus_srcu, idx); |
15dbf27c | 5876 | |
4aeb0b42 | 5877 | return pmu; |
5c92d124 IM |
5878 | } |
5879 | ||
0793a61d | 5880 | /* |
cdd6c482 | 5881 | * Allocate and initialize a event structure |
0793a61d | 5882 | */ |
cdd6c482 | 5883 | static struct perf_event * |
c3f00c70 | 5884 | perf_event_alloc(struct perf_event_attr *attr, int cpu, |
d580ff86 PZ |
5885 | struct task_struct *task, |
5886 | struct perf_event *group_leader, | |
5887 | struct perf_event *parent_event, | |
4dc0da86 AK |
5888 | perf_overflow_handler_t overflow_handler, |
5889 | void *context) | |
0793a61d | 5890 | { |
51b0fe39 | 5891 | struct pmu *pmu; |
cdd6c482 IM |
5892 | struct perf_event *event; |
5893 | struct hw_perf_event *hwc; | |
d5d2bc0d | 5894 | long err; |
0793a61d | 5895 | |
66832eb4 ON |
5896 | if ((unsigned)cpu >= nr_cpu_ids) { |
5897 | if (!task || cpu != -1) | |
5898 | return ERR_PTR(-EINVAL); | |
5899 | } | |
5900 | ||
c3f00c70 | 5901 | event = kzalloc(sizeof(*event), GFP_KERNEL); |
cdd6c482 | 5902 | if (!event) |
d5d2bc0d | 5903 | return ERR_PTR(-ENOMEM); |
0793a61d | 5904 | |
04289bb9 | 5905 | /* |
cdd6c482 | 5906 | * Single events are their own group leaders, with an |
04289bb9 IM |
5907 | * empty sibling list: |
5908 | */ | |
5909 | if (!group_leader) | |
cdd6c482 | 5910 | group_leader = event; |
04289bb9 | 5911 | |
cdd6c482 IM |
5912 | mutex_init(&event->child_mutex); |
5913 | INIT_LIST_HEAD(&event->child_list); | |
fccc714b | 5914 | |
cdd6c482 IM |
5915 | INIT_LIST_HEAD(&event->group_entry); |
5916 | INIT_LIST_HEAD(&event->event_entry); | |
5917 | INIT_LIST_HEAD(&event->sibling_list); | |
10c6db11 PZ |
5918 | INIT_LIST_HEAD(&event->rb_entry); |
5919 | ||
cdd6c482 | 5920 | init_waitqueue_head(&event->waitq); |
e360adbe | 5921 | init_irq_work(&event->pending, perf_pending_event); |
0793a61d | 5922 | |
cdd6c482 | 5923 | mutex_init(&event->mmap_mutex); |
7b732a75 | 5924 | |
cdd6c482 IM |
5925 | event->cpu = cpu; |
5926 | event->attr = *attr; | |
5927 | event->group_leader = group_leader; | |
5928 | event->pmu = NULL; | |
cdd6c482 | 5929 | event->oncpu = -1; |
a96bbc16 | 5930 | |
cdd6c482 | 5931 | event->parent = parent_event; |
b84fbc9f | 5932 | |
cdd6c482 IM |
5933 | event->ns = get_pid_ns(current->nsproxy->pid_ns); |
5934 | event->id = atomic64_inc_return(&perf_event_id); | |
a96bbc16 | 5935 | |
cdd6c482 | 5936 | event->state = PERF_EVENT_STATE_INACTIVE; |
329d876d | 5937 | |
d580ff86 PZ |
5938 | if (task) { |
5939 | event->attach_state = PERF_ATTACH_TASK; | |
5940 | #ifdef CONFIG_HAVE_HW_BREAKPOINT | |
5941 | /* | |
5942 | * hw_breakpoint is a bit difficult here.. | |
5943 | */ | |
5944 | if (attr->type == PERF_TYPE_BREAKPOINT) | |
5945 | event->hw.bp_target = task; | |
5946 | #endif | |
5947 | } | |
5948 | ||
4dc0da86 | 5949 | if (!overflow_handler && parent_event) { |
b326e956 | 5950 | overflow_handler = parent_event->overflow_handler; |
4dc0da86 AK |
5951 | context = parent_event->overflow_handler_context; |
5952 | } | |
66832eb4 | 5953 | |
b326e956 | 5954 | event->overflow_handler = overflow_handler; |
4dc0da86 | 5955 | event->overflow_handler_context = context; |
97eaf530 | 5956 | |
0d48696f | 5957 | if (attr->disabled) |
cdd6c482 | 5958 | event->state = PERF_EVENT_STATE_OFF; |
a86ed508 | 5959 | |
4aeb0b42 | 5960 | pmu = NULL; |
b8e83514 | 5961 | |
cdd6c482 | 5962 | hwc = &event->hw; |
bd2b5b12 | 5963 | hwc->sample_period = attr->sample_period; |
0d48696f | 5964 | if (attr->freq && attr->sample_freq) |
bd2b5b12 | 5965 | hwc->sample_period = 1; |
eced1dfc | 5966 | hwc->last_period = hwc->sample_period; |
bd2b5b12 | 5967 | |
e7850595 | 5968 | local64_set(&hwc->period_left, hwc->sample_period); |
60db5e09 | 5969 | |
2023b359 | 5970 | /* |
cdd6c482 | 5971 | * we currently do not support PERF_FORMAT_GROUP on inherited events |
2023b359 | 5972 | */ |
3dab77fb | 5973 | if (attr->inherit && (attr->read_format & PERF_FORMAT_GROUP)) |
2023b359 PZ |
5974 | goto done; |
5975 | ||
b0a873eb | 5976 | pmu = perf_init_event(event); |
974802ea | 5977 | |
d5d2bc0d PM |
5978 | done: |
5979 | err = 0; | |
4aeb0b42 | 5980 | if (!pmu) |
d5d2bc0d | 5981 | err = -EINVAL; |
4aeb0b42 RR |
5982 | else if (IS_ERR(pmu)) |
5983 | err = PTR_ERR(pmu); | |
5c92d124 | 5984 | |
d5d2bc0d | 5985 | if (err) { |
cdd6c482 IM |
5986 | if (event->ns) |
5987 | put_pid_ns(event->ns); | |
5988 | kfree(event); | |
d5d2bc0d | 5989 | return ERR_PTR(err); |
621a01ea | 5990 | } |
d5d2bc0d | 5991 | |
cdd6c482 | 5992 | if (!event->parent) { |
82cd6def | 5993 | if (event->attach_state & PERF_ATTACH_TASK) |
c5905afb | 5994 | static_key_slow_inc(&perf_sched_events.key); |
3af9e859 | 5995 | if (event->attr.mmap || event->attr.mmap_data) |
cdd6c482 IM |
5996 | atomic_inc(&nr_mmap_events); |
5997 | if (event->attr.comm) | |
5998 | atomic_inc(&nr_comm_events); | |
5999 | if (event->attr.task) | |
6000 | atomic_inc(&nr_task_events); | |
927c7a9e FW |
6001 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) { |
6002 | err = get_callchain_buffers(); | |
6003 | if (err) { | |
6004 | free_event(event); | |
6005 | return ERR_PTR(err); | |
6006 | } | |
6007 | } | |
d010b332 SE |
6008 | if (has_branch_stack(event)) { |
6009 | static_key_slow_inc(&perf_sched_events.key); | |
6010 | if (!(event->attach_state & PERF_ATTACH_TASK)) | |
6011 | atomic_inc(&per_cpu(perf_branch_stack_events, | |
6012 | event->cpu)); | |
6013 | } | |
f344011c | 6014 | } |
9ee318a7 | 6015 | |
cdd6c482 | 6016 | return event; |
0793a61d TG |
6017 | } |
6018 | ||
cdd6c482 IM |
6019 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
6020 | struct perf_event_attr *attr) | |
974802ea | 6021 | { |
974802ea | 6022 | u32 size; |
cdf8073d | 6023 | int ret; |
974802ea PZ |
6024 | |
6025 | if (!access_ok(VERIFY_WRITE, uattr, PERF_ATTR_SIZE_VER0)) | |
6026 | return -EFAULT; | |
6027 | ||
6028 | /* | |
6029 | * zero the full structure, so that a short copy will be nice. | |
6030 | */ | |
6031 | memset(attr, 0, sizeof(*attr)); | |
6032 | ||
6033 | ret = get_user(size, &uattr->size); | |
6034 | if (ret) | |
6035 | return ret; | |
6036 | ||
6037 | if (size > PAGE_SIZE) /* silly large */ | |
6038 | goto err_size; | |
6039 | ||
6040 | if (!size) /* abi compat */ | |
6041 | size = PERF_ATTR_SIZE_VER0; | |
6042 | ||
6043 | if (size < PERF_ATTR_SIZE_VER0) | |
6044 | goto err_size; | |
6045 | ||
6046 | /* | |
6047 | * If we're handed a bigger struct than we know of, | |
cdf8073d IS |
6048 | * ensure all the unknown bits are 0 - i.e. new |
6049 | * user-space does not rely on any kernel feature | |
6050 | * extensions we dont know about yet. | |
974802ea PZ |
6051 | */ |
6052 | if (size > sizeof(*attr)) { | |
cdf8073d IS |
6053 | unsigned char __user *addr; |
6054 | unsigned char __user *end; | |
6055 | unsigned char val; | |
974802ea | 6056 | |
cdf8073d IS |
6057 | addr = (void __user *)uattr + sizeof(*attr); |
6058 | end = (void __user *)uattr + size; | |
974802ea | 6059 | |
cdf8073d | 6060 | for (; addr < end; addr++) { |
974802ea PZ |
6061 | ret = get_user(val, addr); |
6062 | if (ret) | |
6063 | return ret; | |
6064 | if (val) | |
6065 | goto err_size; | |
6066 | } | |
b3e62e35 | 6067 | size = sizeof(*attr); |
974802ea PZ |
6068 | } |
6069 | ||
6070 | ret = copy_from_user(attr, uattr, size); | |
6071 | if (ret) | |
6072 | return -EFAULT; | |
6073 | ||
cd757645 | 6074 | if (attr->__reserved_1) |
974802ea PZ |
6075 | return -EINVAL; |
6076 | ||
6077 | if (attr->sample_type & ~(PERF_SAMPLE_MAX-1)) | |
6078 | return -EINVAL; | |
6079 | ||
6080 | if (attr->read_format & ~(PERF_FORMAT_MAX-1)) | |
6081 | return -EINVAL; | |
6082 | ||
bce38cd5 SE |
6083 | if (attr->sample_type & PERF_SAMPLE_BRANCH_STACK) { |
6084 | u64 mask = attr->branch_sample_type; | |
6085 | ||
6086 | /* only using defined bits */ | |
6087 | if (mask & ~(PERF_SAMPLE_BRANCH_MAX-1)) | |
6088 | return -EINVAL; | |
6089 | ||
6090 | /* at least one branch bit must be set */ | |
6091 | if (!(mask & ~PERF_SAMPLE_BRANCH_PLM_ALL)) | |
6092 | return -EINVAL; | |
6093 | ||
6094 | /* kernel level capture: check permissions */ | |
6095 | if ((mask & PERF_SAMPLE_BRANCH_PERM_PLM) | |
6096 | && perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) | |
6097 | return -EACCES; | |
6098 | ||
6099 | /* propagate priv level, when not set for branch */ | |
6100 | if (!(mask & PERF_SAMPLE_BRANCH_PLM_ALL)) { | |
6101 | ||
6102 | /* exclude_kernel checked on syscall entry */ | |
6103 | if (!attr->exclude_kernel) | |
6104 | mask |= PERF_SAMPLE_BRANCH_KERNEL; | |
6105 | ||
6106 | if (!attr->exclude_user) | |
6107 | mask |= PERF_SAMPLE_BRANCH_USER; | |
6108 | ||
6109 | if (!attr->exclude_hv) | |
6110 | mask |= PERF_SAMPLE_BRANCH_HV; | |
6111 | /* | |
6112 | * adjust user setting (for HW filter setup) | |
6113 | */ | |
6114 | attr->branch_sample_type = mask; | |
6115 | } | |
6116 | } | |
974802ea PZ |
6117 | out: |
6118 | return ret; | |
6119 | ||
6120 | err_size: | |
6121 | put_user(sizeof(*attr), &uattr->size); | |
6122 | ret = -E2BIG; | |
6123 | goto out; | |
6124 | } | |
6125 | ||
ac9721f3 PZ |
6126 | static int |
6127 | perf_event_set_output(struct perf_event *event, struct perf_event *output_event) | |
a4be7c27 | 6128 | { |
76369139 | 6129 | struct ring_buffer *rb = NULL, *old_rb = NULL; |
a4be7c27 PZ |
6130 | int ret = -EINVAL; |
6131 | ||
ac9721f3 | 6132 | if (!output_event) |
a4be7c27 PZ |
6133 | goto set; |
6134 | ||
ac9721f3 PZ |
6135 | /* don't allow circular references */ |
6136 | if (event == output_event) | |
a4be7c27 PZ |
6137 | goto out; |
6138 | ||
0f139300 PZ |
6139 | /* |
6140 | * Don't allow cross-cpu buffers | |
6141 | */ | |
6142 | if (output_event->cpu != event->cpu) | |
6143 | goto out; | |
6144 | ||
6145 | /* | |
76369139 | 6146 | * If its not a per-cpu rb, it must be the same task. |
0f139300 PZ |
6147 | */ |
6148 | if (output_event->cpu == -1 && output_event->ctx != event->ctx) | |
6149 | goto out; | |
6150 | ||
a4be7c27 | 6151 | set: |
cdd6c482 | 6152 | mutex_lock(&event->mmap_mutex); |
ac9721f3 PZ |
6153 | /* Can't redirect output if we've got an active mmap() */ |
6154 | if (atomic_read(&event->mmap_count)) | |
6155 | goto unlock; | |
a4be7c27 | 6156 | |
ac9721f3 | 6157 | if (output_event) { |
76369139 FW |
6158 | /* get the rb we want to redirect to */ |
6159 | rb = ring_buffer_get(output_event); | |
6160 | if (!rb) | |
ac9721f3 | 6161 | goto unlock; |
a4be7c27 PZ |
6162 | } |
6163 | ||
76369139 FW |
6164 | old_rb = event->rb; |
6165 | rcu_assign_pointer(event->rb, rb); | |
10c6db11 PZ |
6166 | if (old_rb) |
6167 | ring_buffer_detach(event, old_rb); | |
a4be7c27 | 6168 | ret = 0; |
ac9721f3 PZ |
6169 | unlock: |
6170 | mutex_unlock(&event->mmap_mutex); | |
6171 | ||
76369139 FW |
6172 | if (old_rb) |
6173 | ring_buffer_put(old_rb); | |
a4be7c27 | 6174 | out: |
a4be7c27 PZ |
6175 | return ret; |
6176 | } | |
6177 | ||
0793a61d | 6178 | /** |
cdd6c482 | 6179 | * sys_perf_event_open - open a performance event, associate it to a task/cpu |
9f66a381 | 6180 | * |
cdd6c482 | 6181 | * @attr_uptr: event_id type attributes for monitoring/sampling |
0793a61d | 6182 | * @pid: target pid |
9f66a381 | 6183 | * @cpu: target cpu |
cdd6c482 | 6184 | * @group_fd: group leader event fd |
0793a61d | 6185 | */ |
cdd6c482 IM |
6186 | SYSCALL_DEFINE5(perf_event_open, |
6187 | struct perf_event_attr __user *, attr_uptr, | |
2743a5b0 | 6188 | pid_t, pid, int, cpu, int, group_fd, unsigned long, flags) |
0793a61d | 6189 | { |
b04243ef PZ |
6190 | struct perf_event *group_leader = NULL, *output_event = NULL; |
6191 | struct perf_event *event, *sibling; | |
cdd6c482 IM |
6192 | struct perf_event_attr attr; |
6193 | struct perf_event_context *ctx; | |
6194 | struct file *event_file = NULL; | |
04289bb9 | 6195 | struct file *group_file = NULL; |
38a81da2 | 6196 | struct task_struct *task = NULL; |
89a1e187 | 6197 | struct pmu *pmu; |
ea635c64 | 6198 | int event_fd; |
b04243ef | 6199 | int move_group = 0; |
04289bb9 | 6200 | int fput_needed = 0; |
dc86cabe | 6201 | int err; |
0793a61d | 6202 | |
2743a5b0 | 6203 | /* for future expandability... */ |
e5d1367f | 6204 | if (flags & ~PERF_FLAG_ALL) |
2743a5b0 PM |
6205 | return -EINVAL; |
6206 | ||
dc86cabe IM |
6207 | err = perf_copy_attr(attr_uptr, &attr); |
6208 | if (err) | |
6209 | return err; | |
eab656ae | 6210 | |
0764771d PZ |
6211 | if (!attr.exclude_kernel) { |
6212 | if (perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) | |
6213 | return -EACCES; | |
6214 | } | |
6215 | ||
df58ab24 | 6216 | if (attr.freq) { |
cdd6c482 | 6217 | if (attr.sample_freq > sysctl_perf_event_sample_rate) |
df58ab24 PZ |
6218 | return -EINVAL; |
6219 | } | |
6220 | ||
e5d1367f SE |
6221 | /* |
6222 | * In cgroup mode, the pid argument is used to pass the fd | |
6223 | * opened to the cgroup directory in cgroupfs. The cpu argument | |
6224 | * designates the cpu on which to monitor threads from that | |
6225 | * cgroup. | |
6226 | */ | |
6227 | if ((flags & PERF_FLAG_PID_CGROUP) && (pid == -1 || cpu == -1)) | |
6228 | return -EINVAL; | |
6229 | ||
ea635c64 AV |
6230 | event_fd = get_unused_fd_flags(O_RDWR); |
6231 | if (event_fd < 0) | |
6232 | return event_fd; | |
6233 | ||
ac9721f3 PZ |
6234 | if (group_fd != -1) { |
6235 | group_leader = perf_fget_light(group_fd, &fput_needed); | |
6236 | if (IS_ERR(group_leader)) { | |
6237 | err = PTR_ERR(group_leader); | |
d14b12d7 | 6238 | goto err_fd; |
ac9721f3 PZ |
6239 | } |
6240 | group_file = group_leader->filp; | |
6241 | if (flags & PERF_FLAG_FD_OUTPUT) | |
6242 | output_event = group_leader; | |
6243 | if (flags & PERF_FLAG_FD_NO_GROUP) | |
6244 | group_leader = NULL; | |
6245 | } | |
6246 | ||
e5d1367f | 6247 | if (pid != -1 && !(flags & PERF_FLAG_PID_CGROUP)) { |
c6be5a5c PZ |
6248 | task = find_lively_task_by_vpid(pid); |
6249 | if (IS_ERR(task)) { | |
6250 | err = PTR_ERR(task); | |
6251 | goto err_group_fd; | |
6252 | } | |
6253 | } | |
6254 | ||
4dc0da86 AK |
6255 | event = perf_event_alloc(&attr, cpu, task, group_leader, NULL, |
6256 | NULL, NULL); | |
d14b12d7 SE |
6257 | if (IS_ERR(event)) { |
6258 | err = PTR_ERR(event); | |
c6be5a5c | 6259 | goto err_task; |
d14b12d7 SE |
6260 | } |
6261 | ||
e5d1367f SE |
6262 | if (flags & PERF_FLAG_PID_CGROUP) { |
6263 | err = perf_cgroup_connect(pid, event, &attr, group_leader); | |
6264 | if (err) | |
6265 | goto err_alloc; | |
08309379 PZ |
6266 | /* |
6267 | * one more event: | |
6268 | * - that has cgroup constraint on event->cpu | |
6269 | * - that may need work on context switch | |
6270 | */ | |
6271 | atomic_inc(&per_cpu(perf_cgroup_events, event->cpu)); | |
c5905afb | 6272 | static_key_slow_inc(&perf_sched_events.key); |
e5d1367f SE |
6273 | } |
6274 | ||
89a1e187 PZ |
6275 | /* |
6276 | * Special case software events and allow them to be part of | |
6277 | * any hardware group. | |
6278 | */ | |
6279 | pmu = event->pmu; | |
b04243ef PZ |
6280 | |
6281 | if (group_leader && | |
6282 | (is_software_event(event) != is_software_event(group_leader))) { | |
6283 | if (is_software_event(event)) { | |
6284 | /* | |
6285 | * If event and group_leader are not both a software | |
6286 | * event, and event is, then group leader is not. | |
6287 | * | |
6288 | * Allow the addition of software events to !software | |
6289 | * groups, this is safe because software events never | |
6290 | * fail to schedule. | |
6291 | */ | |
6292 | pmu = group_leader->pmu; | |
6293 | } else if (is_software_event(group_leader) && | |
6294 | (group_leader->group_flags & PERF_GROUP_SOFTWARE)) { | |
6295 | /* | |
6296 | * In case the group is a pure software group, and we | |
6297 | * try to add a hardware event, move the whole group to | |
6298 | * the hardware context. | |
6299 | */ | |
6300 | move_group = 1; | |
6301 | } | |
6302 | } | |
89a1e187 PZ |
6303 | |
6304 | /* | |
6305 | * Get the target context (task or percpu): | |
6306 | */ | |
38a81da2 | 6307 | ctx = find_get_context(pmu, task, cpu); |
89a1e187 PZ |
6308 | if (IS_ERR(ctx)) { |
6309 | err = PTR_ERR(ctx); | |
c6be5a5c | 6310 | goto err_alloc; |
89a1e187 PZ |
6311 | } |
6312 | ||
fd1edb3a PZ |
6313 | if (task) { |
6314 | put_task_struct(task); | |
6315 | task = NULL; | |
6316 | } | |
6317 | ||
ccff286d | 6318 | /* |
cdd6c482 | 6319 | * Look up the group leader (we will attach this event to it): |
04289bb9 | 6320 | */ |
ac9721f3 | 6321 | if (group_leader) { |
dc86cabe | 6322 | err = -EINVAL; |
04289bb9 | 6323 | |
04289bb9 | 6324 | /* |
ccff286d IM |
6325 | * Do not allow a recursive hierarchy (this new sibling |
6326 | * becoming part of another group-sibling): | |
6327 | */ | |
6328 | if (group_leader->group_leader != group_leader) | |
c3f00c70 | 6329 | goto err_context; |
ccff286d IM |
6330 | /* |
6331 | * Do not allow to attach to a group in a different | |
6332 | * task or CPU context: | |
04289bb9 | 6333 | */ |
b04243ef PZ |
6334 | if (move_group) { |
6335 | if (group_leader->ctx->type != ctx->type) | |
6336 | goto err_context; | |
6337 | } else { | |
6338 | if (group_leader->ctx != ctx) | |
6339 | goto err_context; | |
6340 | } | |
6341 | ||
3b6f9e5c PM |
6342 | /* |
6343 | * Only a group leader can be exclusive or pinned | |
6344 | */ | |
0d48696f | 6345 | if (attr.exclusive || attr.pinned) |
c3f00c70 | 6346 | goto err_context; |
ac9721f3 PZ |
6347 | } |
6348 | ||
6349 | if (output_event) { | |
6350 | err = perf_event_set_output(event, output_event); | |
6351 | if (err) | |
c3f00c70 | 6352 | goto err_context; |
ac9721f3 | 6353 | } |
0793a61d | 6354 | |
ea635c64 AV |
6355 | event_file = anon_inode_getfile("[perf_event]", &perf_fops, event, O_RDWR); |
6356 | if (IS_ERR(event_file)) { | |
6357 | err = PTR_ERR(event_file); | |
c3f00c70 | 6358 | goto err_context; |
ea635c64 | 6359 | } |
9b51f66d | 6360 | |
b04243ef PZ |
6361 | if (move_group) { |
6362 | struct perf_event_context *gctx = group_leader->ctx; | |
6363 | ||
6364 | mutex_lock(&gctx->mutex); | |
fe4b04fa | 6365 | perf_remove_from_context(group_leader); |
b04243ef PZ |
6366 | list_for_each_entry(sibling, &group_leader->sibling_list, |
6367 | group_entry) { | |
fe4b04fa | 6368 | perf_remove_from_context(sibling); |
b04243ef PZ |
6369 | put_ctx(gctx); |
6370 | } | |
6371 | mutex_unlock(&gctx->mutex); | |
6372 | put_ctx(gctx); | |
ea635c64 | 6373 | } |
9b51f66d | 6374 | |
cdd6c482 | 6375 | event->filp = event_file; |
ad3a37de | 6376 | WARN_ON_ONCE(ctx->parent_ctx); |
d859e29f | 6377 | mutex_lock(&ctx->mutex); |
b04243ef PZ |
6378 | |
6379 | if (move_group) { | |
6380 | perf_install_in_context(ctx, group_leader, cpu); | |
6381 | get_ctx(ctx); | |
6382 | list_for_each_entry(sibling, &group_leader->sibling_list, | |
6383 | group_entry) { | |
6384 | perf_install_in_context(ctx, sibling, cpu); | |
6385 | get_ctx(ctx); | |
6386 | } | |
6387 | } | |
6388 | ||
cdd6c482 | 6389 | perf_install_in_context(ctx, event, cpu); |
ad3a37de | 6390 | ++ctx->generation; |
fe4b04fa | 6391 | perf_unpin_context(ctx); |
d859e29f | 6392 | mutex_unlock(&ctx->mutex); |
9b51f66d | 6393 | |
cdd6c482 | 6394 | event->owner = current; |
8882135b | 6395 | |
cdd6c482 IM |
6396 | mutex_lock(¤t->perf_event_mutex); |
6397 | list_add_tail(&event->owner_entry, ¤t->perf_event_list); | |
6398 | mutex_unlock(¤t->perf_event_mutex); | |
082ff5a2 | 6399 | |
c320c7b7 ACM |
6400 | /* |
6401 | * Precalculate sample_data sizes | |
6402 | */ | |
6403 | perf_event__header_size(event); | |
6844c09d | 6404 | perf_event__id_header_size(event); |
c320c7b7 | 6405 | |
8a49542c PZ |
6406 | /* |
6407 | * Drop the reference on the group_event after placing the | |
6408 | * new event on the sibling_list. This ensures destruction | |
6409 | * of the group leader will find the pointer to itself in | |
6410 | * perf_group_detach(). | |
6411 | */ | |
ea635c64 AV |
6412 | fput_light(group_file, fput_needed); |
6413 | fd_install(event_fd, event_file); | |
6414 | return event_fd; | |
0793a61d | 6415 | |
c3f00c70 | 6416 | err_context: |
fe4b04fa | 6417 | perf_unpin_context(ctx); |
ea635c64 | 6418 | put_ctx(ctx); |
c6be5a5c | 6419 | err_alloc: |
ea635c64 | 6420 | free_event(event); |
e7d0bc04 PZ |
6421 | err_task: |
6422 | if (task) | |
6423 | put_task_struct(task); | |
89a1e187 | 6424 | err_group_fd: |
dc86cabe | 6425 | fput_light(group_file, fput_needed); |
ea635c64 AV |
6426 | err_fd: |
6427 | put_unused_fd(event_fd); | |
dc86cabe | 6428 | return err; |
0793a61d TG |
6429 | } |
6430 | ||
fb0459d7 AV |
6431 | /** |
6432 | * perf_event_create_kernel_counter | |
6433 | * | |
6434 | * @attr: attributes of the counter to create | |
6435 | * @cpu: cpu in which the counter is bound | |
38a81da2 | 6436 | * @task: task to profile (NULL for percpu) |
fb0459d7 AV |
6437 | */ |
6438 | struct perf_event * | |
6439 | perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, | |
38a81da2 | 6440 | struct task_struct *task, |
4dc0da86 AK |
6441 | perf_overflow_handler_t overflow_handler, |
6442 | void *context) | |
fb0459d7 | 6443 | { |
fb0459d7 | 6444 | struct perf_event_context *ctx; |
c3f00c70 | 6445 | struct perf_event *event; |
fb0459d7 | 6446 | int err; |
d859e29f | 6447 | |
fb0459d7 AV |
6448 | /* |
6449 | * Get the target context (task or percpu): | |
6450 | */ | |
d859e29f | 6451 | |
4dc0da86 AK |
6452 | event = perf_event_alloc(attr, cpu, task, NULL, NULL, |
6453 | overflow_handler, context); | |
c3f00c70 PZ |
6454 | if (IS_ERR(event)) { |
6455 | err = PTR_ERR(event); | |
6456 | goto err; | |
6457 | } | |
d859e29f | 6458 | |
38a81da2 | 6459 | ctx = find_get_context(event->pmu, task, cpu); |
c6567f64 FW |
6460 | if (IS_ERR(ctx)) { |
6461 | err = PTR_ERR(ctx); | |
c3f00c70 | 6462 | goto err_free; |
d859e29f | 6463 | } |
fb0459d7 AV |
6464 | |
6465 | event->filp = NULL; | |
6466 | WARN_ON_ONCE(ctx->parent_ctx); | |
6467 | mutex_lock(&ctx->mutex); | |
6468 | perf_install_in_context(ctx, event, cpu); | |
6469 | ++ctx->generation; | |
fe4b04fa | 6470 | perf_unpin_context(ctx); |
fb0459d7 AV |
6471 | mutex_unlock(&ctx->mutex); |
6472 | ||
fb0459d7 AV |
6473 | return event; |
6474 | ||
c3f00c70 PZ |
6475 | err_free: |
6476 | free_event(event); | |
6477 | err: | |
c6567f64 | 6478 | return ERR_PTR(err); |
9b51f66d | 6479 | } |
fb0459d7 | 6480 | EXPORT_SYMBOL_GPL(perf_event_create_kernel_counter); |
9b51f66d | 6481 | |
cdd6c482 | 6482 | static void sync_child_event(struct perf_event *child_event, |
38b200d6 | 6483 | struct task_struct *child) |
d859e29f | 6484 | { |
cdd6c482 | 6485 | struct perf_event *parent_event = child_event->parent; |
8bc20959 | 6486 | u64 child_val; |
d859e29f | 6487 | |
cdd6c482 IM |
6488 | if (child_event->attr.inherit_stat) |
6489 | perf_event_read_event(child_event, child); | |
38b200d6 | 6490 | |
b5e58793 | 6491 | child_val = perf_event_count(child_event); |
d859e29f PM |
6492 | |
6493 | /* | |
6494 | * Add back the child's count to the parent's count: | |
6495 | */ | |
a6e6dea6 | 6496 | atomic64_add(child_val, &parent_event->child_count); |
cdd6c482 IM |
6497 | atomic64_add(child_event->total_time_enabled, |
6498 | &parent_event->child_total_time_enabled); | |
6499 | atomic64_add(child_event->total_time_running, | |
6500 | &parent_event->child_total_time_running); | |
d859e29f PM |
6501 | |
6502 | /* | |
cdd6c482 | 6503 | * Remove this event from the parent's list |
d859e29f | 6504 | */ |
cdd6c482 IM |
6505 | WARN_ON_ONCE(parent_event->ctx->parent_ctx); |
6506 | mutex_lock(&parent_event->child_mutex); | |
6507 | list_del_init(&child_event->child_list); | |
6508 | mutex_unlock(&parent_event->child_mutex); | |
d859e29f PM |
6509 | |
6510 | /* | |
cdd6c482 | 6511 | * Release the parent event, if this was the last |
d859e29f PM |
6512 | * reference to it. |
6513 | */ | |
cdd6c482 | 6514 | fput(parent_event->filp); |
d859e29f PM |
6515 | } |
6516 | ||
9b51f66d | 6517 | static void |
cdd6c482 IM |
6518 | __perf_event_exit_task(struct perf_event *child_event, |
6519 | struct perf_event_context *child_ctx, | |
38b200d6 | 6520 | struct task_struct *child) |
9b51f66d | 6521 | { |
38b435b1 PZ |
6522 | if (child_event->parent) { |
6523 | raw_spin_lock_irq(&child_ctx->lock); | |
6524 | perf_group_detach(child_event); | |
6525 | raw_spin_unlock_irq(&child_ctx->lock); | |
6526 | } | |
9b51f66d | 6527 | |
fe4b04fa | 6528 | perf_remove_from_context(child_event); |
0cc0c027 | 6529 | |
9b51f66d | 6530 | /* |
38b435b1 | 6531 | * It can happen that the parent exits first, and has events |
9b51f66d | 6532 | * that are still around due to the child reference. These |
38b435b1 | 6533 | * events need to be zapped. |
9b51f66d | 6534 | */ |
38b435b1 | 6535 | if (child_event->parent) { |
cdd6c482 IM |
6536 | sync_child_event(child_event, child); |
6537 | free_event(child_event); | |
4bcf349a | 6538 | } |
9b51f66d IM |
6539 | } |
6540 | ||
8dc85d54 | 6541 | static void perf_event_exit_task_context(struct task_struct *child, int ctxn) |
9b51f66d | 6542 | { |
cdd6c482 IM |
6543 | struct perf_event *child_event, *tmp; |
6544 | struct perf_event_context *child_ctx; | |
a63eaf34 | 6545 | unsigned long flags; |
9b51f66d | 6546 | |
8dc85d54 | 6547 | if (likely(!child->perf_event_ctxp[ctxn])) { |
cdd6c482 | 6548 | perf_event_task(child, NULL, 0); |
9b51f66d | 6549 | return; |
9f498cc5 | 6550 | } |
9b51f66d | 6551 | |
a63eaf34 | 6552 | local_irq_save(flags); |
ad3a37de PM |
6553 | /* |
6554 | * We can't reschedule here because interrupts are disabled, | |
6555 | * and either child is current or it is a task that can't be | |
6556 | * scheduled, so we are now safe from rescheduling changing | |
6557 | * our context. | |
6558 | */ | |
806839b2 | 6559 | child_ctx = rcu_dereference_raw(child->perf_event_ctxp[ctxn]); |
c93f7669 PM |
6560 | |
6561 | /* | |
6562 | * Take the context lock here so that if find_get_context is | |
cdd6c482 | 6563 | * reading child->perf_event_ctxp, we wait until it has |
c93f7669 PM |
6564 | * incremented the context's refcount before we do put_ctx below. |
6565 | */ | |
e625cce1 | 6566 | raw_spin_lock(&child_ctx->lock); |
04dc2dbb | 6567 | task_ctx_sched_out(child_ctx); |
8dc85d54 | 6568 | child->perf_event_ctxp[ctxn] = NULL; |
71a851b4 PZ |
6569 | /* |
6570 | * If this context is a clone; unclone it so it can't get | |
6571 | * swapped to another process while we're removing all | |
cdd6c482 | 6572 | * the events from it. |
71a851b4 PZ |
6573 | */ |
6574 | unclone_ctx(child_ctx); | |
5e942bb3 | 6575 | update_context_time(child_ctx); |
e625cce1 | 6576 | raw_spin_unlock_irqrestore(&child_ctx->lock, flags); |
9f498cc5 PZ |
6577 | |
6578 | /* | |
cdd6c482 IM |
6579 | * Report the task dead after unscheduling the events so that we |
6580 | * won't get any samples after PERF_RECORD_EXIT. We can however still | |
6581 | * get a few PERF_RECORD_READ events. | |
9f498cc5 | 6582 | */ |
cdd6c482 | 6583 | perf_event_task(child, child_ctx, 0); |
a63eaf34 | 6584 | |
66fff224 PZ |
6585 | /* |
6586 | * We can recurse on the same lock type through: | |
6587 | * | |
cdd6c482 IM |
6588 | * __perf_event_exit_task() |
6589 | * sync_child_event() | |
6590 | * fput(parent_event->filp) | |
66fff224 PZ |
6591 | * perf_release() |
6592 | * mutex_lock(&ctx->mutex) | |
6593 | * | |
6594 | * But since its the parent context it won't be the same instance. | |
6595 | */ | |
a0507c84 | 6596 | mutex_lock(&child_ctx->mutex); |
a63eaf34 | 6597 | |
8bc20959 | 6598 | again: |
889ff015 FW |
6599 | list_for_each_entry_safe(child_event, tmp, &child_ctx->pinned_groups, |
6600 | group_entry) | |
6601 | __perf_event_exit_task(child_event, child_ctx, child); | |
6602 | ||
6603 | list_for_each_entry_safe(child_event, tmp, &child_ctx->flexible_groups, | |
65abc865 | 6604 | group_entry) |
cdd6c482 | 6605 | __perf_event_exit_task(child_event, child_ctx, child); |
8bc20959 PZ |
6606 | |
6607 | /* | |
cdd6c482 | 6608 | * If the last event was a group event, it will have appended all |
8bc20959 PZ |
6609 | * its siblings to the list, but we obtained 'tmp' before that which |
6610 | * will still point to the list head terminating the iteration. | |
6611 | */ | |
889ff015 FW |
6612 | if (!list_empty(&child_ctx->pinned_groups) || |
6613 | !list_empty(&child_ctx->flexible_groups)) | |
8bc20959 | 6614 | goto again; |
a63eaf34 PM |
6615 | |
6616 | mutex_unlock(&child_ctx->mutex); | |
6617 | ||
6618 | put_ctx(child_ctx); | |
9b51f66d IM |
6619 | } |
6620 | ||
8dc85d54 PZ |
6621 | /* |
6622 | * When a child task exits, feed back event values to parent events. | |
6623 | */ | |
6624 | void perf_event_exit_task(struct task_struct *child) | |
6625 | { | |
8882135b | 6626 | struct perf_event *event, *tmp; |
8dc85d54 PZ |
6627 | int ctxn; |
6628 | ||
8882135b PZ |
6629 | mutex_lock(&child->perf_event_mutex); |
6630 | list_for_each_entry_safe(event, tmp, &child->perf_event_list, | |
6631 | owner_entry) { | |
6632 | list_del_init(&event->owner_entry); | |
6633 | ||
6634 | /* | |
6635 | * Ensure the list deletion is visible before we clear | |
6636 | * the owner, closes a race against perf_release() where | |
6637 | * we need to serialize on the owner->perf_event_mutex. | |
6638 | */ | |
6639 | smp_wmb(); | |
6640 | event->owner = NULL; | |
6641 | } | |
6642 | mutex_unlock(&child->perf_event_mutex); | |
6643 | ||
8dc85d54 PZ |
6644 | for_each_task_context_nr(ctxn) |
6645 | perf_event_exit_task_context(child, ctxn); | |
6646 | } | |
6647 | ||
889ff015 FW |
6648 | static void perf_free_event(struct perf_event *event, |
6649 | struct perf_event_context *ctx) | |
6650 | { | |
6651 | struct perf_event *parent = event->parent; | |
6652 | ||
6653 | if (WARN_ON_ONCE(!parent)) | |
6654 | return; | |
6655 | ||
6656 | mutex_lock(&parent->child_mutex); | |
6657 | list_del_init(&event->child_list); | |
6658 | mutex_unlock(&parent->child_mutex); | |
6659 | ||
6660 | fput(parent->filp); | |
6661 | ||
8a49542c | 6662 | perf_group_detach(event); |
889ff015 FW |
6663 | list_del_event(event, ctx); |
6664 | free_event(event); | |
6665 | } | |
6666 | ||
bbbee908 PZ |
6667 | /* |
6668 | * free an unexposed, unused context as created by inheritance by | |
8dc85d54 | 6669 | * perf_event_init_task below, used by fork() in case of fail. |
bbbee908 | 6670 | */ |
cdd6c482 | 6671 | void perf_event_free_task(struct task_struct *task) |
bbbee908 | 6672 | { |
8dc85d54 | 6673 | struct perf_event_context *ctx; |
cdd6c482 | 6674 | struct perf_event *event, *tmp; |
8dc85d54 | 6675 | int ctxn; |
bbbee908 | 6676 | |
8dc85d54 PZ |
6677 | for_each_task_context_nr(ctxn) { |
6678 | ctx = task->perf_event_ctxp[ctxn]; | |
6679 | if (!ctx) | |
6680 | continue; | |
bbbee908 | 6681 | |
8dc85d54 | 6682 | mutex_lock(&ctx->mutex); |
bbbee908 | 6683 | again: |
8dc85d54 PZ |
6684 | list_for_each_entry_safe(event, tmp, &ctx->pinned_groups, |
6685 | group_entry) | |
6686 | perf_free_event(event, ctx); | |
bbbee908 | 6687 | |
8dc85d54 PZ |
6688 | list_for_each_entry_safe(event, tmp, &ctx->flexible_groups, |
6689 | group_entry) | |
6690 | perf_free_event(event, ctx); | |
bbbee908 | 6691 | |
8dc85d54 PZ |
6692 | if (!list_empty(&ctx->pinned_groups) || |
6693 | !list_empty(&ctx->flexible_groups)) | |
6694 | goto again; | |
bbbee908 | 6695 | |
8dc85d54 | 6696 | mutex_unlock(&ctx->mutex); |
bbbee908 | 6697 | |
8dc85d54 PZ |
6698 | put_ctx(ctx); |
6699 | } | |
889ff015 FW |
6700 | } |
6701 | ||
4e231c79 PZ |
6702 | void perf_event_delayed_put(struct task_struct *task) |
6703 | { | |
6704 | int ctxn; | |
6705 | ||
6706 | for_each_task_context_nr(ctxn) | |
6707 | WARN_ON_ONCE(task->perf_event_ctxp[ctxn]); | |
6708 | } | |
6709 | ||
97dee4f3 PZ |
6710 | /* |
6711 | * inherit a event from parent task to child task: | |
6712 | */ | |
6713 | static struct perf_event * | |
6714 | inherit_event(struct perf_event *parent_event, | |
6715 | struct task_struct *parent, | |
6716 | struct perf_event_context *parent_ctx, | |
6717 | struct task_struct *child, | |
6718 | struct perf_event *group_leader, | |
6719 | struct perf_event_context *child_ctx) | |
6720 | { | |
6721 | struct perf_event *child_event; | |
cee010ec | 6722 | unsigned long flags; |
97dee4f3 PZ |
6723 | |
6724 | /* | |
6725 | * Instead of creating recursive hierarchies of events, | |
6726 | * we link inherited events back to the original parent, | |
6727 | * which has a filp for sure, which we use as the reference | |
6728 | * count: | |
6729 | */ | |
6730 | if (parent_event->parent) | |
6731 | parent_event = parent_event->parent; | |
6732 | ||
6733 | child_event = perf_event_alloc(&parent_event->attr, | |
6734 | parent_event->cpu, | |
d580ff86 | 6735 | child, |
97dee4f3 | 6736 | group_leader, parent_event, |
4dc0da86 | 6737 | NULL, NULL); |
97dee4f3 PZ |
6738 | if (IS_ERR(child_event)) |
6739 | return child_event; | |
6740 | get_ctx(child_ctx); | |
6741 | ||
6742 | /* | |
6743 | * Make the child state follow the state of the parent event, | |
6744 | * not its attr.disabled bit. We hold the parent's mutex, | |
6745 | * so we won't race with perf_event_{en, dis}able_family. | |
6746 | */ | |
6747 | if (parent_event->state >= PERF_EVENT_STATE_INACTIVE) | |
6748 | child_event->state = PERF_EVENT_STATE_INACTIVE; | |
6749 | else | |
6750 | child_event->state = PERF_EVENT_STATE_OFF; | |
6751 | ||
6752 | if (parent_event->attr.freq) { | |
6753 | u64 sample_period = parent_event->hw.sample_period; | |
6754 | struct hw_perf_event *hwc = &child_event->hw; | |
6755 | ||
6756 | hwc->sample_period = sample_period; | |
6757 | hwc->last_period = sample_period; | |
6758 | ||
6759 | local64_set(&hwc->period_left, sample_period); | |
6760 | } | |
6761 | ||
6762 | child_event->ctx = child_ctx; | |
6763 | child_event->overflow_handler = parent_event->overflow_handler; | |
4dc0da86 AK |
6764 | child_event->overflow_handler_context |
6765 | = parent_event->overflow_handler_context; | |
97dee4f3 | 6766 | |
614b6780 TG |
6767 | /* |
6768 | * Precalculate sample_data sizes | |
6769 | */ | |
6770 | perf_event__header_size(child_event); | |
6844c09d | 6771 | perf_event__id_header_size(child_event); |
614b6780 | 6772 | |
97dee4f3 PZ |
6773 | /* |
6774 | * Link it up in the child's context: | |
6775 | */ | |
cee010ec | 6776 | raw_spin_lock_irqsave(&child_ctx->lock, flags); |
97dee4f3 | 6777 | add_event_to_ctx(child_event, child_ctx); |
cee010ec | 6778 | raw_spin_unlock_irqrestore(&child_ctx->lock, flags); |
97dee4f3 PZ |
6779 | |
6780 | /* | |
6781 | * Get a reference to the parent filp - we will fput it | |
6782 | * when the child event exits. This is safe to do because | |
6783 | * we are in the parent and we know that the filp still | |
6784 | * exists and has a nonzero count: | |
6785 | */ | |
6786 | atomic_long_inc(&parent_event->filp->f_count); | |
6787 | ||
6788 | /* | |
6789 | * Link this into the parent event's child list | |
6790 | */ | |
6791 | WARN_ON_ONCE(parent_event->ctx->parent_ctx); | |
6792 | mutex_lock(&parent_event->child_mutex); | |
6793 | list_add_tail(&child_event->child_list, &parent_event->child_list); | |
6794 | mutex_unlock(&parent_event->child_mutex); | |
6795 | ||
6796 | return child_event; | |
6797 | } | |
6798 | ||
6799 | static int inherit_group(struct perf_event *parent_event, | |
6800 | struct task_struct *parent, | |
6801 | struct perf_event_context *parent_ctx, | |
6802 | struct task_struct *child, | |
6803 | struct perf_event_context *child_ctx) | |
6804 | { | |
6805 | struct perf_event *leader; | |
6806 | struct perf_event *sub; | |
6807 | struct perf_event *child_ctr; | |
6808 | ||
6809 | leader = inherit_event(parent_event, parent, parent_ctx, | |
6810 | child, NULL, child_ctx); | |
6811 | if (IS_ERR(leader)) | |
6812 | return PTR_ERR(leader); | |
6813 | list_for_each_entry(sub, &parent_event->sibling_list, group_entry) { | |
6814 | child_ctr = inherit_event(sub, parent, parent_ctx, | |
6815 | child, leader, child_ctx); | |
6816 | if (IS_ERR(child_ctr)) | |
6817 | return PTR_ERR(child_ctr); | |
6818 | } | |
6819 | return 0; | |
889ff015 FW |
6820 | } |
6821 | ||
6822 | static int | |
6823 | inherit_task_group(struct perf_event *event, struct task_struct *parent, | |
6824 | struct perf_event_context *parent_ctx, | |
8dc85d54 | 6825 | struct task_struct *child, int ctxn, |
889ff015 FW |
6826 | int *inherited_all) |
6827 | { | |
6828 | int ret; | |
8dc85d54 | 6829 | struct perf_event_context *child_ctx; |
889ff015 FW |
6830 | |
6831 | if (!event->attr.inherit) { | |
6832 | *inherited_all = 0; | |
6833 | return 0; | |
bbbee908 PZ |
6834 | } |
6835 | ||
fe4b04fa | 6836 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 FW |
6837 | if (!child_ctx) { |
6838 | /* | |
6839 | * This is executed from the parent task context, so | |
6840 | * inherit events that have been marked for cloning. | |
6841 | * First allocate and initialize a context for the | |
6842 | * child. | |
6843 | */ | |
bbbee908 | 6844 | |
eb184479 | 6845 | child_ctx = alloc_perf_context(event->pmu, child); |
889ff015 FW |
6846 | if (!child_ctx) |
6847 | return -ENOMEM; | |
bbbee908 | 6848 | |
8dc85d54 | 6849 | child->perf_event_ctxp[ctxn] = child_ctx; |
889ff015 FW |
6850 | } |
6851 | ||
6852 | ret = inherit_group(event, parent, parent_ctx, | |
6853 | child, child_ctx); | |
6854 | ||
6855 | if (ret) | |
6856 | *inherited_all = 0; | |
6857 | ||
6858 | return ret; | |
bbbee908 PZ |
6859 | } |
6860 | ||
9b51f66d | 6861 | /* |
cdd6c482 | 6862 | * Initialize the perf_event context in task_struct |
9b51f66d | 6863 | */ |
8dc85d54 | 6864 | int perf_event_init_context(struct task_struct *child, int ctxn) |
9b51f66d | 6865 | { |
889ff015 | 6866 | struct perf_event_context *child_ctx, *parent_ctx; |
cdd6c482 IM |
6867 | struct perf_event_context *cloned_ctx; |
6868 | struct perf_event *event; | |
9b51f66d | 6869 | struct task_struct *parent = current; |
564c2b21 | 6870 | int inherited_all = 1; |
dddd3379 | 6871 | unsigned long flags; |
6ab423e0 | 6872 | int ret = 0; |
9b51f66d | 6873 | |
8dc85d54 | 6874 | if (likely(!parent->perf_event_ctxp[ctxn])) |
6ab423e0 PZ |
6875 | return 0; |
6876 | ||
ad3a37de | 6877 | /* |
25346b93 PM |
6878 | * If the parent's context is a clone, pin it so it won't get |
6879 | * swapped under us. | |
ad3a37de | 6880 | */ |
8dc85d54 | 6881 | parent_ctx = perf_pin_task_context(parent, ctxn); |
25346b93 | 6882 | |
ad3a37de PM |
6883 | /* |
6884 | * No need to check if parent_ctx != NULL here; since we saw | |
6885 | * it non-NULL earlier, the only reason for it to become NULL | |
6886 | * is if we exit, and since we're currently in the middle of | |
6887 | * a fork we can't be exiting at the same time. | |
6888 | */ | |
ad3a37de | 6889 | |
9b51f66d IM |
6890 | /* |
6891 | * Lock the parent list. No need to lock the child - not PID | |
6892 | * hashed yet and not running, so nobody can access it. | |
6893 | */ | |
d859e29f | 6894 | mutex_lock(&parent_ctx->mutex); |
9b51f66d IM |
6895 | |
6896 | /* | |
6897 | * We dont have to disable NMIs - we are only looking at | |
6898 | * the list, not manipulating it: | |
6899 | */ | |
889ff015 | 6900 | list_for_each_entry(event, &parent_ctx->pinned_groups, group_entry) { |
8dc85d54 PZ |
6901 | ret = inherit_task_group(event, parent, parent_ctx, |
6902 | child, ctxn, &inherited_all); | |
889ff015 FW |
6903 | if (ret) |
6904 | break; | |
6905 | } | |
b93f7978 | 6906 | |
dddd3379 TG |
6907 | /* |
6908 | * We can't hold ctx->lock when iterating the ->flexible_group list due | |
6909 | * to allocations, but we need to prevent rotation because | |
6910 | * rotate_ctx() will change the list from interrupt context. | |
6911 | */ | |
6912 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); | |
6913 | parent_ctx->rotate_disable = 1; | |
6914 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); | |
6915 | ||
889ff015 | 6916 | list_for_each_entry(event, &parent_ctx->flexible_groups, group_entry) { |
8dc85d54 PZ |
6917 | ret = inherit_task_group(event, parent, parent_ctx, |
6918 | child, ctxn, &inherited_all); | |
889ff015 | 6919 | if (ret) |
9b51f66d | 6920 | break; |
564c2b21 PM |
6921 | } |
6922 | ||
dddd3379 TG |
6923 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); |
6924 | parent_ctx->rotate_disable = 0; | |
dddd3379 | 6925 | |
8dc85d54 | 6926 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 | 6927 | |
05cbaa28 | 6928 | if (child_ctx && inherited_all) { |
564c2b21 PM |
6929 | /* |
6930 | * Mark the child context as a clone of the parent | |
6931 | * context, or of whatever the parent is a clone of. | |
c5ed5145 PZ |
6932 | * |
6933 | * Note that if the parent is a clone, the holding of | |
6934 | * parent_ctx->lock avoids it from being uncloned. | |
564c2b21 | 6935 | */ |
c5ed5145 | 6936 | cloned_ctx = parent_ctx->parent_ctx; |
ad3a37de PM |
6937 | if (cloned_ctx) { |
6938 | child_ctx->parent_ctx = cloned_ctx; | |
25346b93 | 6939 | child_ctx->parent_gen = parent_ctx->parent_gen; |
564c2b21 PM |
6940 | } else { |
6941 | child_ctx->parent_ctx = parent_ctx; | |
6942 | child_ctx->parent_gen = parent_ctx->generation; | |
6943 | } | |
6944 | get_ctx(child_ctx->parent_ctx); | |
9b51f66d IM |
6945 | } |
6946 | ||
c5ed5145 | 6947 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); |
d859e29f | 6948 | mutex_unlock(&parent_ctx->mutex); |
6ab423e0 | 6949 | |
25346b93 | 6950 | perf_unpin_context(parent_ctx); |
fe4b04fa | 6951 | put_ctx(parent_ctx); |
ad3a37de | 6952 | |
6ab423e0 | 6953 | return ret; |
9b51f66d IM |
6954 | } |
6955 | ||
8dc85d54 PZ |
6956 | /* |
6957 | * Initialize the perf_event context in task_struct | |
6958 | */ | |
6959 | int perf_event_init_task(struct task_struct *child) | |
6960 | { | |
6961 | int ctxn, ret; | |
6962 | ||
8550d7cb ON |
6963 | memset(child->perf_event_ctxp, 0, sizeof(child->perf_event_ctxp)); |
6964 | mutex_init(&child->perf_event_mutex); | |
6965 | INIT_LIST_HEAD(&child->perf_event_list); | |
6966 | ||
8dc85d54 PZ |
6967 | for_each_task_context_nr(ctxn) { |
6968 | ret = perf_event_init_context(child, ctxn); | |
6969 | if (ret) | |
6970 | return ret; | |
6971 | } | |
6972 | ||
6973 | return 0; | |
6974 | } | |
6975 | ||
220b140b PM |
6976 | static void __init perf_event_init_all_cpus(void) |
6977 | { | |
b28ab83c | 6978 | struct swevent_htable *swhash; |
220b140b | 6979 | int cpu; |
220b140b PM |
6980 | |
6981 | for_each_possible_cpu(cpu) { | |
b28ab83c PZ |
6982 | swhash = &per_cpu(swevent_htable, cpu); |
6983 | mutex_init(&swhash->hlist_mutex); | |
e9d2b064 | 6984 | INIT_LIST_HEAD(&per_cpu(rotation_list, cpu)); |
220b140b PM |
6985 | } |
6986 | } | |
6987 | ||
cdd6c482 | 6988 | static void __cpuinit perf_event_init_cpu(int cpu) |
0793a61d | 6989 | { |
108b02cf | 6990 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
0793a61d | 6991 | |
b28ab83c | 6992 | mutex_lock(&swhash->hlist_mutex); |
4536e4d1 | 6993 | if (swhash->hlist_refcount > 0) { |
76e1d904 FW |
6994 | struct swevent_hlist *hlist; |
6995 | ||
b28ab83c PZ |
6996 | hlist = kzalloc_node(sizeof(*hlist), GFP_KERNEL, cpu_to_node(cpu)); |
6997 | WARN_ON(!hlist); | |
6998 | rcu_assign_pointer(swhash->swevent_hlist, hlist); | |
76e1d904 | 6999 | } |
b28ab83c | 7000 | mutex_unlock(&swhash->hlist_mutex); |
0793a61d TG |
7001 | } |
7002 | ||
c277443c | 7003 | #if defined CONFIG_HOTPLUG_CPU || defined CONFIG_KEXEC |
e9d2b064 | 7004 | static void perf_pmu_rotate_stop(struct pmu *pmu) |
0793a61d | 7005 | { |
e9d2b064 PZ |
7006 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
7007 | ||
7008 | WARN_ON(!irqs_disabled()); | |
7009 | ||
7010 | list_del_init(&cpuctx->rotation_list); | |
7011 | } | |
7012 | ||
108b02cf | 7013 | static void __perf_event_exit_context(void *__info) |
0793a61d | 7014 | { |
108b02cf | 7015 | struct perf_event_context *ctx = __info; |
cdd6c482 | 7016 | struct perf_event *event, *tmp; |
0793a61d | 7017 | |
108b02cf | 7018 | perf_pmu_rotate_stop(ctx->pmu); |
b5ab4cd5 | 7019 | |
889ff015 | 7020 | list_for_each_entry_safe(event, tmp, &ctx->pinned_groups, group_entry) |
fe4b04fa | 7021 | __perf_remove_from_context(event); |
889ff015 | 7022 | list_for_each_entry_safe(event, tmp, &ctx->flexible_groups, group_entry) |
fe4b04fa | 7023 | __perf_remove_from_context(event); |
0793a61d | 7024 | } |
108b02cf PZ |
7025 | |
7026 | static void perf_event_exit_cpu_context(int cpu) | |
7027 | { | |
7028 | struct perf_event_context *ctx; | |
7029 | struct pmu *pmu; | |
7030 | int idx; | |
7031 | ||
7032 | idx = srcu_read_lock(&pmus_srcu); | |
7033 | list_for_each_entry_rcu(pmu, &pmus, entry) { | |
917bdd1c | 7034 | ctx = &per_cpu_ptr(pmu->pmu_cpu_context, cpu)->ctx; |
108b02cf PZ |
7035 | |
7036 | mutex_lock(&ctx->mutex); | |
7037 | smp_call_function_single(cpu, __perf_event_exit_context, ctx, 1); | |
7038 | mutex_unlock(&ctx->mutex); | |
7039 | } | |
7040 | srcu_read_unlock(&pmus_srcu, idx); | |
108b02cf PZ |
7041 | } |
7042 | ||
cdd6c482 | 7043 | static void perf_event_exit_cpu(int cpu) |
0793a61d | 7044 | { |
b28ab83c | 7045 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
d859e29f | 7046 | |
b28ab83c PZ |
7047 | mutex_lock(&swhash->hlist_mutex); |
7048 | swevent_hlist_release(swhash); | |
7049 | mutex_unlock(&swhash->hlist_mutex); | |
76e1d904 | 7050 | |
108b02cf | 7051 | perf_event_exit_cpu_context(cpu); |
0793a61d TG |
7052 | } |
7053 | #else | |
cdd6c482 | 7054 | static inline void perf_event_exit_cpu(int cpu) { } |
0793a61d TG |
7055 | #endif |
7056 | ||
c277443c PZ |
7057 | static int |
7058 | perf_reboot(struct notifier_block *notifier, unsigned long val, void *v) | |
7059 | { | |
7060 | int cpu; | |
7061 | ||
7062 | for_each_online_cpu(cpu) | |
7063 | perf_event_exit_cpu(cpu); | |
7064 | ||
7065 | return NOTIFY_OK; | |
7066 | } | |
7067 | ||
7068 | /* | |
7069 | * Run the perf reboot notifier at the very last possible moment so that | |
7070 | * the generic watchdog code runs as long as possible. | |
7071 | */ | |
7072 | static struct notifier_block perf_reboot_notifier = { | |
7073 | .notifier_call = perf_reboot, | |
7074 | .priority = INT_MIN, | |
7075 | }; | |
7076 | ||
0793a61d TG |
7077 | static int __cpuinit |
7078 | perf_cpu_notify(struct notifier_block *self, unsigned long action, void *hcpu) | |
7079 | { | |
7080 | unsigned int cpu = (long)hcpu; | |
7081 | ||
4536e4d1 | 7082 | switch (action & ~CPU_TASKS_FROZEN) { |
0793a61d TG |
7083 | |
7084 | case CPU_UP_PREPARE: | |
5e11637e | 7085 | case CPU_DOWN_FAILED: |
cdd6c482 | 7086 | perf_event_init_cpu(cpu); |
0793a61d TG |
7087 | break; |
7088 | ||
5e11637e | 7089 | case CPU_UP_CANCELED: |
0793a61d | 7090 | case CPU_DOWN_PREPARE: |
cdd6c482 | 7091 | perf_event_exit_cpu(cpu); |
0793a61d TG |
7092 | break; |
7093 | ||
7094 | default: | |
7095 | break; | |
7096 | } | |
7097 | ||
7098 | return NOTIFY_OK; | |
7099 | } | |
7100 | ||
cdd6c482 | 7101 | void __init perf_event_init(void) |
0793a61d | 7102 | { |
3c502e7a JW |
7103 | int ret; |
7104 | ||
2e80a82a PZ |
7105 | idr_init(&pmu_idr); |
7106 | ||
220b140b | 7107 | perf_event_init_all_cpus(); |
b0a873eb | 7108 | init_srcu_struct(&pmus_srcu); |
2e80a82a PZ |
7109 | perf_pmu_register(&perf_swevent, "software", PERF_TYPE_SOFTWARE); |
7110 | perf_pmu_register(&perf_cpu_clock, NULL, -1); | |
7111 | perf_pmu_register(&perf_task_clock, NULL, -1); | |
b0a873eb PZ |
7112 | perf_tp_register(); |
7113 | perf_cpu_notifier(perf_cpu_notify); | |
c277443c | 7114 | register_reboot_notifier(&perf_reboot_notifier); |
3c502e7a JW |
7115 | |
7116 | ret = init_hw_breakpoint(); | |
7117 | WARN(ret, "hw_breakpoint initialization failed with: %d", ret); | |
b2029520 GN |
7118 | |
7119 | /* do not patch jump label more than once per second */ | |
7120 | jump_label_rate_limit(&perf_sched_events, HZ); | |
b01c3a00 JO |
7121 | |
7122 | /* | |
7123 | * Build time assertion that we keep the data_head at the intended | |
7124 | * location. IOW, validation we got the __reserved[] size right. | |
7125 | */ | |
7126 | BUILD_BUG_ON((offsetof(struct perf_event_mmap_page, data_head)) | |
7127 | != 1024); | |
0793a61d | 7128 | } |
abe43400 PZ |
7129 | |
7130 | static int __init perf_event_sysfs_init(void) | |
7131 | { | |
7132 | struct pmu *pmu; | |
7133 | int ret; | |
7134 | ||
7135 | mutex_lock(&pmus_lock); | |
7136 | ||
7137 | ret = bus_register(&pmu_bus); | |
7138 | if (ret) | |
7139 | goto unlock; | |
7140 | ||
7141 | list_for_each_entry(pmu, &pmus, entry) { | |
7142 | if (!pmu->name || pmu->type < 0) | |
7143 | continue; | |
7144 | ||
7145 | ret = pmu_dev_alloc(pmu); | |
7146 | WARN(ret, "Failed to register pmu: %s, reason %d\n", pmu->name, ret); | |
7147 | } | |
7148 | pmu_bus_running = 1; | |
7149 | ret = 0; | |
7150 | ||
7151 | unlock: | |
7152 | mutex_unlock(&pmus_lock); | |
7153 | ||
7154 | return ret; | |
7155 | } | |
7156 | device_initcall(perf_event_sysfs_init); | |
e5d1367f SE |
7157 | |
7158 | #ifdef CONFIG_CGROUP_PERF | |
761b3ef5 | 7159 | static struct cgroup_subsys_state *perf_cgroup_create(struct cgroup *cont) |
e5d1367f SE |
7160 | { |
7161 | struct perf_cgroup *jc; | |
e5d1367f | 7162 | |
1b15d055 | 7163 | jc = kzalloc(sizeof(*jc), GFP_KERNEL); |
e5d1367f SE |
7164 | if (!jc) |
7165 | return ERR_PTR(-ENOMEM); | |
7166 | ||
e5d1367f SE |
7167 | jc->info = alloc_percpu(struct perf_cgroup_info); |
7168 | if (!jc->info) { | |
7169 | kfree(jc); | |
7170 | return ERR_PTR(-ENOMEM); | |
7171 | } | |
7172 | ||
e5d1367f SE |
7173 | return &jc->css; |
7174 | } | |
7175 | ||
761b3ef5 | 7176 | static void perf_cgroup_destroy(struct cgroup *cont) |
e5d1367f SE |
7177 | { |
7178 | struct perf_cgroup *jc; | |
7179 | jc = container_of(cgroup_subsys_state(cont, perf_subsys_id), | |
7180 | struct perf_cgroup, css); | |
7181 | free_percpu(jc->info); | |
7182 | kfree(jc); | |
7183 | } | |
7184 | ||
7185 | static int __perf_cgroup_move(void *info) | |
7186 | { | |
7187 | struct task_struct *task = info; | |
7188 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT | PERF_CGROUP_SWIN); | |
7189 | return 0; | |
7190 | } | |
7191 | ||
761b3ef5 | 7192 | static void perf_cgroup_attach(struct cgroup *cgrp, struct cgroup_taskset *tset) |
e5d1367f | 7193 | { |
bb9d97b6 TH |
7194 | struct task_struct *task; |
7195 | ||
7196 | cgroup_taskset_for_each(task, cgrp, tset) | |
7197 | task_function_call(task, __perf_cgroup_move, task); | |
e5d1367f SE |
7198 | } |
7199 | ||
761b3ef5 LZ |
7200 | static void perf_cgroup_exit(struct cgroup *cgrp, struct cgroup *old_cgrp, |
7201 | struct task_struct *task) | |
e5d1367f SE |
7202 | { |
7203 | /* | |
7204 | * cgroup_exit() is called in the copy_process() failure path. | |
7205 | * Ignore this case since the task hasn't ran yet, this avoids | |
7206 | * trying to poke a half freed task state from generic code. | |
7207 | */ | |
7208 | if (!(task->flags & PF_EXITING)) | |
7209 | return; | |
7210 | ||
bb9d97b6 | 7211 | task_function_call(task, __perf_cgroup_move, task); |
e5d1367f SE |
7212 | } |
7213 | ||
7214 | struct cgroup_subsys perf_subsys = { | |
e7e7ee2e IM |
7215 | .name = "perf_event", |
7216 | .subsys_id = perf_subsys_id, | |
7217 | .create = perf_cgroup_create, | |
7218 | .destroy = perf_cgroup_destroy, | |
7219 | .exit = perf_cgroup_exit, | |
bb9d97b6 | 7220 | .attach = perf_cgroup_attach, |
e5d1367f SE |
7221 | }; |
7222 | #endif /* CONFIG_CGROUP_PERF */ |