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Commit | Line | Data |
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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> |
12351ef8 | 21 | #include <linux/tick.h> |
0793a61d | 22 | #include <linux/sysfs.h> |
22a4f650 | 23 | #include <linux/dcache.h> |
0793a61d | 24 | #include <linux/percpu.h> |
22a4f650 | 25 | #include <linux/ptrace.h> |
c277443c | 26 | #include <linux/reboot.h> |
b9cacc7b | 27 | #include <linux/vmstat.h> |
abe43400 | 28 | #include <linux/device.h> |
6e5fdeed | 29 | #include <linux/export.h> |
906010b2 | 30 | #include <linux/vmalloc.h> |
b9cacc7b PZ |
31 | #include <linux/hardirq.h> |
32 | #include <linux/rculist.h> | |
0793a61d TG |
33 | #include <linux/uaccess.h> |
34 | #include <linux/syscalls.h> | |
35 | #include <linux/anon_inodes.h> | |
aa9c4c0f | 36 | #include <linux/kernel_stat.h> |
cdd6c482 | 37 | #include <linux/perf_event.h> |
6fb2915d | 38 | #include <linux/ftrace_event.h> |
3c502e7a | 39 | #include <linux/hw_breakpoint.h> |
c5ebcedb | 40 | #include <linux/mm_types.h> |
877c6856 | 41 | #include <linux/cgroup.h> |
0793a61d | 42 | |
76369139 FW |
43 | #include "internal.h" |
44 | ||
4e193bd4 TB |
45 | #include <asm/irq_regs.h> |
46 | ||
fe4b04fa | 47 | struct remote_function_call { |
e7e7ee2e IM |
48 | struct task_struct *p; |
49 | int (*func)(void *info); | |
50 | void *info; | |
51 | int ret; | |
fe4b04fa PZ |
52 | }; |
53 | ||
54 | static void remote_function(void *data) | |
55 | { | |
56 | struct remote_function_call *tfc = data; | |
57 | struct task_struct *p = tfc->p; | |
58 | ||
59 | if (p) { | |
60 | tfc->ret = -EAGAIN; | |
61 | if (task_cpu(p) != smp_processor_id() || !task_curr(p)) | |
62 | return; | |
63 | } | |
64 | ||
65 | tfc->ret = tfc->func(tfc->info); | |
66 | } | |
67 | ||
68 | /** | |
69 | * task_function_call - call a function on the cpu on which a task runs | |
70 | * @p: the task to evaluate | |
71 | * @func: the function to be called | |
72 | * @info: the function call argument | |
73 | * | |
74 | * Calls the function @func when the task is currently running. This might | |
75 | * be on the current CPU, which just calls the function directly | |
76 | * | |
77 | * returns: @func return value, or | |
78 | * -ESRCH - when the process isn't running | |
79 | * -EAGAIN - when the process moved away | |
80 | */ | |
81 | static int | |
82 | task_function_call(struct task_struct *p, int (*func) (void *info), void *info) | |
83 | { | |
84 | struct remote_function_call data = { | |
e7e7ee2e IM |
85 | .p = p, |
86 | .func = func, | |
87 | .info = info, | |
88 | .ret = -ESRCH, /* No such (running) process */ | |
fe4b04fa PZ |
89 | }; |
90 | ||
91 | if (task_curr(p)) | |
92 | smp_call_function_single(task_cpu(p), remote_function, &data, 1); | |
93 | ||
94 | return data.ret; | |
95 | } | |
96 | ||
97 | /** | |
98 | * cpu_function_call - call a function on the cpu | |
99 | * @func: the function to be called | |
100 | * @info: the function call argument | |
101 | * | |
102 | * Calls the function @func on the remote cpu. | |
103 | * | |
104 | * returns: @func return value or -ENXIO when the cpu is offline | |
105 | */ | |
106 | static int cpu_function_call(int cpu, int (*func) (void *info), void *info) | |
107 | { | |
108 | struct remote_function_call data = { | |
e7e7ee2e IM |
109 | .p = NULL, |
110 | .func = func, | |
111 | .info = info, | |
112 | .ret = -ENXIO, /* No such CPU */ | |
fe4b04fa PZ |
113 | }; |
114 | ||
115 | smp_call_function_single(cpu, remote_function, &data, 1); | |
116 | ||
117 | return data.ret; | |
118 | } | |
119 | ||
e5d1367f SE |
120 | #define PERF_FLAG_ALL (PERF_FLAG_FD_NO_GROUP |\ |
121 | PERF_FLAG_FD_OUTPUT |\ | |
122 | PERF_FLAG_PID_CGROUP) | |
123 | ||
bce38cd5 SE |
124 | /* |
125 | * branch priv levels that need permission checks | |
126 | */ | |
127 | #define PERF_SAMPLE_BRANCH_PERM_PLM \ | |
128 | (PERF_SAMPLE_BRANCH_KERNEL |\ | |
129 | PERF_SAMPLE_BRANCH_HV) | |
130 | ||
0b3fcf17 SE |
131 | enum event_type_t { |
132 | EVENT_FLEXIBLE = 0x1, | |
133 | EVENT_PINNED = 0x2, | |
134 | EVENT_ALL = EVENT_FLEXIBLE | EVENT_PINNED, | |
135 | }; | |
136 | ||
e5d1367f SE |
137 | /* |
138 | * perf_sched_events : >0 events exist | |
139 | * perf_cgroup_events: >0 per-cpu cgroup events exist on this cpu | |
140 | */ | |
c5905afb | 141 | struct static_key_deferred perf_sched_events __read_mostly; |
e5d1367f | 142 | static DEFINE_PER_CPU(atomic_t, perf_cgroup_events); |
d010b332 | 143 | static DEFINE_PER_CPU(atomic_t, perf_branch_stack_events); |
e5d1367f | 144 | |
cdd6c482 IM |
145 | static atomic_t nr_mmap_events __read_mostly; |
146 | static atomic_t nr_comm_events __read_mostly; | |
147 | static atomic_t nr_task_events __read_mostly; | |
9ee318a7 | 148 | |
108b02cf PZ |
149 | static LIST_HEAD(pmus); |
150 | static DEFINE_MUTEX(pmus_lock); | |
151 | static struct srcu_struct pmus_srcu; | |
152 | ||
0764771d | 153 | /* |
cdd6c482 | 154 | * perf event paranoia level: |
0fbdea19 IM |
155 | * -1 - not paranoid at all |
156 | * 0 - disallow raw tracepoint access for unpriv | |
cdd6c482 | 157 | * 1 - disallow cpu events for unpriv |
0fbdea19 | 158 | * 2 - disallow kernel profiling for unpriv |
0764771d | 159 | */ |
cdd6c482 | 160 | int sysctl_perf_event_paranoid __read_mostly = 1; |
0764771d | 161 | |
20443384 FW |
162 | /* Minimum for 512 kiB + 1 user control page */ |
163 | int sysctl_perf_event_mlock __read_mostly = 512 + (PAGE_SIZE / 1024); /* 'free' kiB per user */ | |
df58ab24 PZ |
164 | |
165 | /* | |
cdd6c482 | 166 | * max perf event sample rate |
df58ab24 | 167 | */ |
14c63f17 DH |
168 | #define DEFAULT_MAX_SAMPLE_RATE 100000 |
169 | #define DEFAULT_SAMPLE_PERIOD_NS (NSEC_PER_SEC / DEFAULT_MAX_SAMPLE_RATE) | |
170 | #define DEFAULT_CPU_TIME_MAX_PERCENT 25 | |
171 | ||
172 | int sysctl_perf_event_sample_rate __read_mostly = DEFAULT_MAX_SAMPLE_RATE; | |
173 | ||
174 | static int max_samples_per_tick __read_mostly = DIV_ROUND_UP(DEFAULT_MAX_SAMPLE_RATE, HZ); | |
175 | static int perf_sample_period_ns __read_mostly = DEFAULT_SAMPLE_PERIOD_NS; | |
176 | ||
177 | static atomic_t perf_sample_allowed_ns __read_mostly = | |
178 | ATOMIC_INIT( DEFAULT_SAMPLE_PERIOD_NS * DEFAULT_CPU_TIME_MAX_PERCENT / 100); | |
179 | ||
180 | void update_perf_cpu_limits(void) | |
181 | { | |
182 | u64 tmp = perf_sample_period_ns; | |
183 | ||
184 | tmp *= sysctl_perf_cpu_time_max_percent; | |
e5302920 | 185 | do_div(tmp, 100); |
14c63f17 DH |
186 | atomic_set(&perf_sample_allowed_ns, tmp); |
187 | } | |
163ec435 | 188 | |
9e630205 SE |
189 | static int perf_rotate_context(struct perf_cpu_context *cpuctx); |
190 | ||
163ec435 PZ |
191 | int perf_proc_update_handler(struct ctl_table *table, int write, |
192 | void __user *buffer, size_t *lenp, | |
193 | loff_t *ppos) | |
194 | { | |
195 | int ret = proc_dointvec(table, write, buffer, lenp, ppos); | |
196 | ||
197 | if (ret || !write) | |
198 | return ret; | |
199 | ||
200 | max_samples_per_tick = DIV_ROUND_UP(sysctl_perf_event_sample_rate, HZ); | |
14c63f17 DH |
201 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; |
202 | update_perf_cpu_limits(); | |
203 | ||
204 | return 0; | |
205 | } | |
206 | ||
207 | int sysctl_perf_cpu_time_max_percent __read_mostly = DEFAULT_CPU_TIME_MAX_PERCENT; | |
208 | ||
209 | int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write, | |
210 | void __user *buffer, size_t *lenp, | |
211 | loff_t *ppos) | |
212 | { | |
213 | int ret = proc_dointvec(table, write, buffer, lenp, ppos); | |
214 | ||
215 | if (ret || !write) | |
216 | return ret; | |
217 | ||
218 | update_perf_cpu_limits(); | |
163ec435 PZ |
219 | |
220 | return 0; | |
221 | } | |
1ccd1549 | 222 | |
14c63f17 DH |
223 | /* |
224 | * perf samples are done in some very critical code paths (NMIs). | |
225 | * If they take too much CPU time, the system can lock up and not | |
226 | * get any real work done. This will drop the sample rate when | |
227 | * we detect that events are taking too long. | |
228 | */ | |
229 | #define NR_ACCUMULATED_SAMPLES 128 | |
230 | DEFINE_PER_CPU(u64, running_sample_length); | |
231 | ||
232 | void perf_sample_event_took(u64 sample_len_ns) | |
233 | { | |
234 | u64 avg_local_sample_len; | |
e5302920 | 235 | u64 local_samples_len; |
14c63f17 DH |
236 | |
237 | if (atomic_read(&perf_sample_allowed_ns) == 0) | |
238 | return; | |
239 | ||
240 | /* decay the counter by 1 average sample */ | |
241 | local_samples_len = __get_cpu_var(running_sample_length); | |
242 | local_samples_len -= local_samples_len/NR_ACCUMULATED_SAMPLES; | |
243 | local_samples_len += sample_len_ns; | |
244 | __get_cpu_var(running_sample_length) = local_samples_len; | |
245 | ||
246 | /* | |
247 | * note: this will be biased artifically low until we have | |
248 | * seen NR_ACCUMULATED_SAMPLES. Doing it this way keeps us | |
249 | * from having to maintain a count. | |
250 | */ | |
251 | avg_local_sample_len = local_samples_len/NR_ACCUMULATED_SAMPLES; | |
252 | ||
253 | if (avg_local_sample_len <= atomic_read(&perf_sample_allowed_ns)) | |
254 | return; | |
255 | ||
256 | if (max_samples_per_tick <= 1) | |
257 | return; | |
258 | ||
259 | max_samples_per_tick = DIV_ROUND_UP(max_samples_per_tick, 2); | |
260 | sysctl_perf_event_sample_rate = max_samples_per_tick * HZ; | |
261 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; | |
262 | ||
263 | printk_ratelimited(KERN_WARNING | |
264 | "perf samples too long (%lld > %d), lowering " | |
265 | "kernel.perf_event_max_sample_rate to %d\n", | |
266 | avg_local_sample_len, | |
267 | atomic_read(&perf_sample_allowed_ns), | |
268 | sysctl_perf_event_sample_rate); | |
269 | ||
270 | update_perf_cpu_limits(); | |
271 | } | |
272 | ||
cdd6c482 | 273 | static atomic64_t perf_event_id; |
a96bbc16 | 274 | |
0b3fcf17 SE |
275 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, |
276 | enum event_type_t event_type); | |
277 | ||
278 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
279 | enum event_type_t event_type, |
280 | struct task_struct *task); | |
281 | ||
282 | static void update_context_time(struct perf_event_context *ctx); | |
283 | static u64 perf_event_time(struct perf_event *event); | |
0b3fcf17 | 284 | |
cdd6c482 | 285 | void __weak perf_event_print_debug(void) { } |
0793a61d | 286 | |
84c79910 | 287 | extern __weak const char *perf_pmu_name(void) |
0793a61d | 288 | { |
84c79910 | 289 | return "pmu"; |
0793a61d TG |
290 | } |
291 | ||
0b3fcf17 SE |
292 | static inline u64 perf_clock(void) |
293 | { | |
294 | return local_clock(); | |
295 | } | |
296 | ||
e5d1367f SE |
297 | static inline struct perf_cpu_context * |
298 | __get_cpu_context(struct perf_event_context *ctx) | |
299 | { | |
300 | return this_cpu_ptr(ctx->pmu->pmu_cpu_context); | |
301 | } | |
302 | ||
facc4307 PZ |
303 | static void perf_ctx_lock(struct perf_cpu_context *cpuctx, |
304 | struct perf_event_context *ctx) | |
305 | { | |
306 | raw_spin_lock(&cpuctx->ctx.lock); | |
307 | if (ctx) | |
308 | raw_spin_lock(&ctx->lock); | |
309 | } | |
310 | ||
311 | static void perf_ctx_unlock(struct perf_cpu_context *cpuctx, | |
312 | struct perf_event_context *ctx) | |
313 | { | |
314 | if (ctx) | |
315 | raw_spin_unlock(&ctx->lock); | |
316 | raw_spin_unlock(&cpuctx->ctx.lock); | |
317 | } | |
318 | ||
e5d1367f SE |
319 | #ifdef CONFIG_CGROUP_PERF |
320 | ||
877c6856 LZ |
321 | /* |
322 | * perf_cgroup_info keeps track of time_enabled for a cgroup. | |
323 | * This is a per-cpu dynamically allocated data structure. | |
324 | */ | |
325 | struct perf_cgroup_info { | |
326 | u64 time; | |
327 | u64 timestamp; | |
328 | }; | |
329 | ||
330 | struct perf_cgroup { | |
331 | struct cgroup_subsys_state css; | |
86e213e1 | 332 | struct perf_cgroup_info __percpu *info; |
877c6856 LZ |
333 | }; |
334 | ||
3f7cce3c SE |
335 | /* |
336 | * Must ensure cgroup is pinned (css_get) before calling | |
337 | * this function. In other words, we cannot call this function | |
338 | * if there is no cgroup event for the current CPU context. | |
339 | */ | |
e5d1367f SE |
340 | static inline struct perf_cgroup * |
341 | perf_cgroup_from_task(struct task_struct *task) | |
342 | { | |
343 | return container_of(task_subsys_state(task, perf_subsys_id), | |
344 | struct perf_cgroup, css); | |
345 | } | |
346 | ||
347 | static inline bool | |
348 | perf_cgroup_match(struct perf_event *event) | |
349 | { | |
350 | struct perf_event_context *ctx = event->ctx; | |
351 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
352 | ||
ef824fa1 TH |
353 | /* @event doesn't care about cgroup */ |
354 | if (!event->cgrp) | |
355 | return true; | |
356 | ||
357 | /* wants specific cgroup scope but @cpuctx isn't associated with any */ | |
358 | if (!cpuctx->cgrp) | |
359 | return false; | |
360 | ||
361 | /* | |
362 | * Cgroup scoping is recursive. An event enabled for a cgroup is | |
363 | * also enabled for all its descendant cgroups. If @cpuctx's | |
364 | * cgroup is a descendant of @event's (the test covers identity | |
365 | * case), it's a match. | |
366 | */ | |
367 | return cgroup_is_descendant(cpuctx->cgrp->css.cgroup, | |
368 | event->cgrp->css.cgroup); | |
e5d1367f SE |
369 | } |
370 | ||
9c5da09d | 371 | static inline bool perf_tryget_cgroup(struct perf_event *event) |
e5d1367f | 372 | { |
9c5da09d | 373 | return css_tryget(&event->cgrp->css); |
e5d1367f SE |
374 | } |
375 | ||
376 | static inline void perf_put_cgroup(struct perf_event *event) | |
377 | { | |
378 | css_put(&event->cgrp->css); | |
379 | } | |
380 | ||
381 | static inline void perf_detach_cgroup(struct perf_event *event) | |
382 | { | |
383 | perf_put_cgroup(event); | |
384 | event->cgrp = NULL; | |
385 | } | |
386 | ||
387 | static inline int is_cgroup_event(struct perf_event *event) | |
388 | { | |
389 | return event->cgrp != NULL; | |
390 | } | |
391 | ||
392 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
393 | { | |
394 | struct perf_cgroup_info *t; | |
395 | ||
396 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
397 | return t->time; | |
398 | } | |
399 | ||
400 | static inline void __update_cgrp_time(struct perf_cgroup *cgrp) | |
401 | { | |
402 | struct perf_cgroup_info *info; | |
403 | u64 now; | |
404 | ||
405 | now = perf_clock(); | |
406 | ||
407 | info = this_cpu_ptr(cgrp->info); | |
408 | ||
409 | info->time += now - info->timestamp; | |
410 | info->timestamp = now; | |
411 | } | |
412 | ||
413 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
414 | { | |
415 | struct perf_cgroup *cgrp_out = cpuctx->cgrp; | |
416 | if (cgrp_out) | |
417 | __update_cgrp_time(cgrp_out); | |
418 | } | |
419 | ||
420 | static inline void update_cgrp_time_from_event(struct perf_event *event) | |
421 | { | |
3f7cce3c SE |
422 | struct perf_cgroup *cgrp; |
423 | ||
e5d1367f | 424 | /* |
3f7cce3c SE |
425 | * ensure we access cgroup data only when needed and |
426 | * when we know the cgroup is pinned (css_get) | |
e5d1367f | 427 | */ |
3f7cce3c | 428 | if (!is_cgroup_event(event)) |
e5d1367f SE |
429 | return; |
430 | ||
3f7cce3c SE |
431 | cgrp = perf_cgroup_from_task(current); |
432 | /* | |
433 | * Do not update time when cgroup is not active | |
434 | */ | |
435 | if (cgrp == event->cgrp) | |
436 | __update_cgrp_time(event->cgrp); | |
e5d1367f SE |
437 | } |
438 | ||
439 | static inline void | |
3f7cce3c SE |
440 | perf_cgroup_set_timestamp(struct task_struct *task, |
441 | struct perf_event_context *ctx) | |
e5d1367f SE |
442 | { |
443 | struct perf_cgroup *cgrp; | |
444 | struct perf_cgroup_info *info; | |
445 | ||
3f7cce3c SE |
446 | /* |
447 | * ctx->lock held by caller | |
448 | * ensure we do not access cgroup data | |
449 | * unless we have the cgroup pinned (css_get) | |
450 | */ | |
451 | if (!task || !ctx->nr_cgroups) | |
e5d1367f SE |
452 | return; |
453 | ||
454 | cgrp = perf_cgroup_from_task(task); | |
455 | info = this_cpu_ptr(cgrp->info); | |
3f7cce3c | 456 | info->timestamp = ctx->timestamp; |
e5d1367f SE |
457 | } |
458 | ||
459 | #define PERF_CGROUP_SWOUT 0x1 /* cgroup switch out every event */ | |
460 | #define PERF_CGROUP_SWIN 0x2 /* cgroup switch in events based on task */ | |
461 | ||
462 | /* | |
463 | * reschedule events based on the cgroup constraint of task. | |
464 | * | |
465 | * mode SWOUT : schedule out everything | |
466 | * mode SWIN : schedule in based on cgroup for next | |
467 | */ | |
468 | void perf_cgroup_switch(struct task_struct *task, int mode) | |
469 | { | |
470 | struct perf_cpu_context *cpuctx; | |
471 | struct pmu *pmu; | |
472 | unsigned long flags; | |
473 | ||
474 | /* | |
475 | * disable interrupts to avoid geting nr_cgroup | |
476 | * changes via __perf_event_disable(). Also | |
477 | * avoids preemption. | |
478 | */ | |
479 | local_irq_save(flags); | |
480 | ||
481 | /* | |
482 | * we reschedule only in the presence of cgroup | |
483 | * constrained events. | |
484 | */ | |
485 | rcu_read_lock(); | |
486 | ||
487 | list_for_each_entry_rcu(pmu, &pmus, entry) { | |
e5d1367f | 488 | cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
95cf59ea PZ |
489 | if (cpuctx->unique_pmu != pmu) |
490 | continue; /* ensure we process each cpuctx once */ | |
e5d1367f | 491 | |
e5d1367f SE |
492 | /* |
493 | * perf_cgroup_events says at least one | |
494 | * context on this CPU has cgroup events. | |
495 | * | |
496 | * ctx->nr_cgroups reports the number of cgroup | |
497 | * events for a context. | |
498 | */ | |
499 | if (cpuctx->ctx.nr_cgroups > 0) { | |
facc4307 PZ |
500 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
501 | perf_pmu_disable(cpuctx->ctx.pmu); | |
e5d1367f SE |
502 | |
503 | if (mode & PERF_CGROUP_SWOUT) { | |
504 | cpu_ctx_sched_out(cpuctx, EVENT_ALL); | |
505 | /* | |
506 | * must not be done before ctxswout due | |
507 | * to event_filter_match() in event_sched_out() | |
508 | */ | |
509 | cpuctx->cgrp = NULL; | |
510 | } | |
511 | ||
512 | if (mode & PERF_CGROUP_SWIN) { | |
e566b76e | 513 | WARN_ON_ONCE(cpuctx->cgrp); |
95cf59ea PZ |
514 | /* |
515 | * set cgrp before ctxsw in to allow | |
516 | * event_filter_match() to not have to pass | |
517 | * task around | |
e5d1367f SE |
518 | */ |
519 | cpuctx->cgrp = perf_cgroup_from_task(task); | |
520 | cpu_ctx_sched_in(cpuctx, EVENT_ALL, task); | |
521 | } | |
facc4307 PZ |
522 | perf_pmu_enable(cpuctx->ctx.pmu); |
523 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
e5d1367f | 524 | } |
e5d1367f SE |
525 | } |
526 | ||
527 | rcu_read_unlock(); | |
528 | ||
529 | local_irq_restore(flags); | |
530 | } | |
531 | ||
a8d757ef SE |
532 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
533 | struct task_struct *next) | |
e5d1367f | 534 | { |
a8d757ef SE |
535 | struct perf_cgroup *cgrp1; |
536 | struct perf_cgroup *cgrp2 = NULL; | |
537 | ||
538 | /* | |
539 | * we come here when we know perf_cgroup_events > 0 | |
540 | */ | |
541 | cgrp1 = perf_cgroup_from_task(task); | |
542 | ||
543 | /* | |
544 | * next is NULL when called from perf_event_enable_on_exec() | |
545 | * that will systematically cause a cgroup_switch() | |
546 | */ | |
547 | if (next) | |
548 | cgrp2 = perf_cgroup_from_task(next); | |
549 | ||
550 | /* | |
551 | * only schedule out current cgroup events if we know | |
552 | * that we are switching to a different cgroup. Otherwise, | |
553 | * do no touch the cgroup events. | |
554 | */ | |
555 | if (cgrp1 != cgrp2) | |
556 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT); | |
e5d1367f SE |
557 | } |
558 | ||
a8d757ef SE |
559 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
560 | struct task_struct *task) | |
e5d1367f | 561 | { |
a8d757ef SE |
562 | struct perf_cgroup *cgrp1; |
563 | struct perf_cgroup *cgrp2 = NULL; | |
564 | ||
565 | /* | |
566 | * we come here when we know perf_cgroup_events > 0 | |
567 | */ | |
568 | cgrp1 = perf_cgroup_from_task(task); | |
569 | ||
570 | /* prev can never be NULL */ | |
571 | cgrp2 = perf_cgroup_from_task(prev); | |
572 | ||
573 | /* | |
574 | * only need to schedule in cgroup events if we are changing | |
575 | * cgroup during ctxsw. Cgroup events were not scheduled | |
576 | * out of ctxsw out if that was not the case. | |
577 | */ | |
578 | if (cgrp1 != cgrp2) | |
579 | perf_cgroup_switch(task, PERF_CGROUP_SWIN); | |
e5d1367f SE |
580 | } |
581 | ||
582 | static inline int perf_cgroup_connect(int fd, struct perf_event *event, | |
583 | struct perf_event_attr *attr, | |
584 | struct perf_event *group_leader) | |
585 | { | |
586 | struct perf_cgroup *cgrp; | |
587 | struct cgroup_subsys_state *css; | |
2903ff01 AV |
588 | struct fd f = fdget(fd); |
589 | int ret = 0; | |
e5d1367f | 590 | |
2903ff01 | 591 | if (!f.file) |
e5d1367f SE |
592 | return -EBADF; |
593 | ||
2903ff01 | 594 | css = cgroup_css_from_dir(f.file, perf_subsys_id); |
3db272c0 LZ |
595 | if (IS_ERR(css)) { |
596 | ret = PTR_ERR(css); | |
597 | goto out; | |
598 | } | |
e5d1367f SE |
599 | |
600 | cgrp = container_of(css, struct perf_cgroup, css); | |
601 | event->cgrp = cgrp; | |
602 | ||
f75e18cb | 603 | /* must be done before we fput() the file */ |
9c5da09d SQ |
604 | if (!perf_tryget_cgroup(event)) { |
605 | event->cgrp = NULL; | |
606 | ret = -ENOENT; | |
607 | goto out; | |
608 | } | |
f75e18cb | 609 | |
e5d1367f SE |
610 | /* |
611 | * all events in a group must monitor | |
612 | * the same cgroup because a task belongs | |
613 | * to only one perf cgroup at a time | |
614 | */ | |
615 | if (group_leader && group_leader->cgrp != cgrp) { | |
616 | perf_detach_cgroup(event); | |
617 | ret = -EINVAL; | |
e5d1367f | 618 | } |
3db272c0 | 619 | out: |
2903ff01 | 620 | fdput(f); |
e5d1367f SE |
621 | return ret; |
622 | } | |
623 | ||
624 | static inline void | |
625 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
626 | { | |
627 | struct perf_cgroup_info *t; | |
628 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
629 | event->shadow_ctx_time = now - t->timestamp; | |
630 | } | |
631 | ||
632 | static inline void | |
633 | perf_cgroup_defer_enabled(struct perf_event *event) | |
634 | { | |
635 | /* | |
636 | * when the current task's perf cgroup does not match | |
637 | * the event's, we need to remember to call the | |
638 | * perf_mark_enable() function the first time a task with | |
639 | * a matching perf cgroup is scheduled in. | |
640 | */ | |
641 | if (is_cgroup_event(event) && !perf_cgroup_match(event)) | |
642 | event->cgrp_defer_enabled = 1; | |
643 | } | |
644 | ||
645 | static inline void | |
646 | perf_cgroup_mark_enabled(struct perf_event *event, | |
647 | struct perf_event_context *ctx) | |
648 | { | |
649 | struct perf_event *sub; | |
650 | u64 tstamp = perf_event_time(event); | |
651 | ||
652 | if (!event->cgrp_defer_enabled) | |
653 | return; | |
654 | ||
655 | event->cgrp_defer_enabled = 0; | |
656 | ||
657 | event->tstamp_enabled = tstamp - event->total_time_enabled; | |
658 | list_for_each_entry(sub, &event->sibling_list, group_entry) { | |
659 | if (sub->state >= PERF_EVENT_STATE_INACTIVE) { | |
660 | sub->tstamp_enabled = tstamp - sub->total_time_enabled; | |
661 | sub->cgrp_defer_enabled = 0; | |
662 | } | |
663 | } | |
664 | } | |
665 | #else /* !CONFIG_CGROUP_PERF */ | |
666 | ||
667 | static inline bool | |
668 | perf_cgroup_match(struct perf_event *event) | |
669 | { | |
670 | return true; | |
671 | } | |
672 | ||
673 | static inline void perf_detach_cgroup(struct perf_event *event) | |
674 | {} | |
675 | ||
676 | static inline int is_cgroup_event(struct perf_event *event) | |
677 | { | |
678 | return 0; | |
679 | } | |
680 | ||
681 | static inline u64 perf_cgroup_event_cgrp_time(struct perf_event *event) | |
682 | { | |
683 | return 0; | |
684 | } | |
685 | ||
686 | static inline void update_cgrp_time_from_event(struct perf_event *event) | |
687 | { | |
688 | } | |
689 | ||
690 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
691 | { | |
692 | } | |
693 | ||
a8d757ef SE |
694 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
695 | struct task_struct *next) | |
e5d1367f SE |
696 | { |
697 | } | |
698 | ||
a8d757ef SE |
699 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
700 | struct task_struct *task) | |
e5d1367f SE |
701 | { |
702 | } | |
703 | ||
704 | static inline int perf_cgroup_connect(pid_t pid, struct perf_event *event, | |
705 | struct perf_event_attr *attr, | |
706 | struct perf_event *group_leader) | |
707 | { | |
708 | return -EINVAL; | |
709 | } | |
710 | ||
711 | static inline void | |
3f7cce3c SE |
712 | perf_cgroup_set_timestamp(struct task_struct *task, |
713 | struct perf_event_context *ctx) | |
e5d1367f SE |
714 | { |
715 | } | |
716 | ||
717 | void | |
718 | perf_cgroup_switch(struct task_struct *task, struct task_struct *next) | |
719 | { | |
720 | } | |
721 | ||
722 | static inline void | |
723 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
724 | { | |
725 | } | |
726 | ||
727 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
728 | { | |
729 | return 0; | |
730 | } | |
731 | ||
732 | static inline void | |
733 | perf_cgroup_defer_enabled(struct perf_event *event) | |
734 | { | |
735 | } | |
736 | ||
737 | static inline void | |
738 | perf_cgroup_mark_enabled(struct perf_event *event, | |
739 | struct perf_event_context *ctx) | |
740 | { | |
741 | } | |
742 | #endif | |
743 | ||
9e630205 SE |
744 | /* |
745 | * set default to be dependent on timer tick just | |
746 | * like original code | |
747 | */ | |
748 | #define PERF_CPU_HRTIMER (1000 / HZ) | |
749 | /* | |
750 | * function must be called with interrupts disbled | |
751 | */ | |
752 | static enum hrtimer_restart perf_cpu_hrtimer_handler(struct hrtimer *hr) | |
753 | { | |
754 | struct perf_cpu_context *cpuctx; | |
755 | enum hrtimer_restart ret = HRTIMER_NORESTART; | |
756 | int rotations = 0; | |
757 | ||
758 | WARN_ON(!irqs_disabled()); | |
759 | ||
760 | cpuctx = container_of(hr, struct perf_cpu_context, hrtimer); | |
761 | ||
762 | rotations = perf_rotate_context(cpuctx); | |
763 | ||
764 | /* | |
765 | * arm timer if needed | |
766 | */ | |
767 | if (rotations) { | |
768 | hrtimer_forward_now(hr, cpuctx->hrtimer_interval); | |
769 | ret = HRTIMER_RESTART; | |
770 | } | |
771 | ||
772 | return ret; | |
773 | } | |
774 | ||
775 | /* CPU is going down */ | |
776 | void perf_cpu_hrtimer_cancel(int cpu) | |
777 | { | |
778 | struct perf_cpu_context *cpuctx; | |
779 | struct pmu *pmu; | |
780 | unsigned long flags; | |
781 | ||
782 | if (WARN_ON(cpu != smp_processor_id())) | |
783 | return; | |
784 | ||
785 | local_irq_save(flags); | |
786 | ||
787 | rcu_read_lock(); | |
788 | ||
789 | list_for_each_entry_rcu(pmu, &pmus, entry) { | |
790 | cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); | |
791 | ||
792 | if (pmu->task_ctx_nr == perf_sw_context) | |
793 | continue; | |
794 | ||
795 | hrtimer_cancel(&cpuctx->hrtimer); | |
796 | } | |
797 | ||
798 | rcu_read_unlock(); | |
799 | ||
800 | local_irq_restore(flags); | |
801 | } | |
802 | ||
803 | static void __perf_cpu_hrtimer_init(struct perf_cpu_context *cpuctx, int cpu) | |
804 | { | |
805 | struct hrtimer *hr = &cpuctx->hrtimer; | |
806 | struct pmu *pmu = cpuctx->ctx.pmu; | |
62b85639 | 807 | int timer; |
9e630205 SE |
808 | |
809 | /* no multiplexing needed for SW PMU */ | |
810 | if (pmu->task_ctx_nr == perf_sw_context) | |
811 | return; | |
812 | ||
62b85639 SE |
813 | /* |
814 | * check default is sane, if not set then force to | |
815 | * default interval (1/tick) | |
816 | */ | |
817 | timer = pmu->hrtimer_interval_ms; | |
818 | if (timer < 1) | |
819 | timer = pmu->hrtimer_interval_ms = PERF_CPU_HRTIMER; | |
820 | ||
821 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * timer); | |
9e630205 SE |
822 | |
823 | hrtimer_init(hr, CLOCK_MONOTONIC, HRTIMER_MODE_REL_PINNED); | |
824 | hr->function = perf_cpu_hrtimer_handler; | |
825 | } | |
826 | ||
827 | static void perf_cpu_hrtimer_restart(struct perf_cpu_context *cpuctx) | |
828 | { | |
829 | struct hrtimer *hr = &cpuctx->hrtimer; | |
830 | struct pmu *pmu = cpuctx->ctx.pmu; | |
831 | ||
832 | /* not for SW PMU */ | |
833 | if (pmu->task_ctx_nr == perf_sw_context) | |
834 | return; | |
835 | ||
836 | if (hrtimer_active(hr)) | |
837 | return; | |
838 | ||
839 | if (!hrtimer_callback_running(hr)) | |
840 | __hrtimer_start_range_ns(hr, cpuctx->hrtimer_interval, | |
841 | 0, HRTIMER_MODE_REL_PINNED, 0); | |
842 | } | |
843 | ||
33696fc0 | 844 | void perf_pmu_disable(struct pmu *pmu) |
9e35ad38 | 845 | { |
33696fc0 PZ |
846 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
847 | if (!(*count)++) | |
848 | pmu->pmu_disable(pmu); | |
9e35ad38 | 849 | } |
9e35ad38 | 850 | |
33696fc0 | 851 | void perf_pmu_enable(struct pmu *pmu) |
9e35ad38 | 852 | { |
33696fc0 PZ |
853 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
854 | if (!--(*count)) | |
855 | pmu->pmu_enable(pmu); | |
9e35ad38 | 856 | } |
9e35ad38 | 857 | |
e9d2b064 PZ |
858 | static DEFINE_PER_CPU(struct list_head, rotation_list); |
859 | ||
860 | /* | |
861 | * perf_pmu_rotate_start() and perf_rotate_context() are fully serialized | |
862 | * because they're strictly cpu affine and rotate_start is called with IRQs | |
863 | * disabled, while rotate_context is called from IRQ context. | |
864 | */ | |
108b02cf | 865 | static void perf_pmu_rotate_start(struct pmu *pmu) |
9e35ad38 | 866 | { |
108b02cf | 867 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
e9d2b064 | 868 | struct list_head *head = &__get_cpu_var(rotation_list); |
b5ab4cd5 | 869 | |
e9d2b064 | 870 | WARN_ON(!irqs_disabled()); |
b5ab4cd5 | 871 | |
12351ef8 FW |
872 | if (list_empty(&cpuctx->rotation_list)) { |
873 | int was_empty = list_empty(head); | |
e9d2b064 | 874 | list_add(&cpuctx->rotation_list, head); |
12351ef8 FW |
875 | if (was_empty) |
876 | tick_nohz_full_kick(); | |
877 | } | |
9e35ad38 | 878 | } |
9e35ad38 | 879 | |
cdd6c482 | 880 | static void get_ctx(struct perf_event_context *ctx) |
a63eaf34 | 881 | { |
e5289d4a | 882 | WARN_ON(!atomic_inc_not_zero(&ctx->refcount)); |
a63eaf34 PM |
883 | } |
884 | ||
cdd6c482 | 885 | static void put_ctx(struct perf_event_context *ctx) |
a63eaf34 | 886 | { |
564c2b21 PM |
887 | if (atomic_dec_and_test(&ctx->refcount)) { |
888 | if (ctx->parent_ctx) | |
889 | put_ctx(ctx->parent_ctx); | |
c93f7669 PM |
890 | if (ctx->task) |
891 | put_task_struct(ctx->task); | |
cb796ff3 | 892 | kfree_rcu(ctx, rcu_head); |
564c2b21 | 893 | } |
a63eaf34 PM |
894 | } |
895 | ||
cdd6c482 | 896 | static void unclone_ctx(struct perf_event_context *ctx) |
71a851b4 PZ |
897 | { |
898 | if (ctx->parent_ctx) { | |
899 | put_ctx(ctx->parent_ctx); | |
900 | ctx->parent_ctx = NULL; | |
901 | } | |
902 | } | |
903 | ||
6844c09d ACM |
904 | static u32 perf_event_pid(struct perf_event *event, struct task_struct *p) |
905 | { | |
906 | /* | |
907 | * only top level events have the pid namespace they were created in | |
908 | */ | |
909 | if (event->parent) | |
910 | event = event->parent; | |
911 | ||
912 | return task_tgid_nr_ns(p, event->ns); | |
913 | } | |
914 | ||
915 | static u32 perf_event_tid(struct perf_event *event, struct task_struct *p) | |
916 | { | |
917 | /* | |
918 | * only top level events have the pid namespace they were created in | |
919 | */ | |
920 | if (event->parent) | |
921 | event = event->parent; | |
922 | ||
923 | return task_pid_nr_ns(p, event->ns); | |
924 | } | |
925 | ||
7f453c24 | 926 | /* |
cdd6c482 | 927 | * If we inherit events we want to return the parent event id |
7f453c24 PZ |
928 | * to userspace. |
929 | */ | |
cdd6c482 | 930 | static u64 primary_event_id(struct perf_event *event) |
7f453c24 | 931 | { |
cdd6c482 | 932 | u64 id = event->id; |
7f453c24 | 933 | |
cdd6c482 IM |
934 | if (event->parent) |
935 | id = event->parent->id; | |
7f453c24 PZ |
936 | |
937 | return id; | |
938 | } | |
939 | ||
25346b93 | 940 | /* |
cdd6c482 | 941 | * Get the perf_event_context for a task and lock it. |
25346b93 PM |
942 | * This has to cope with with the fact that until it is locked, |
943 | * the context could get moved to another task. | |
944 | */ | |
cdd6c482 | 945 | static struct perf_event_context * |
8dc85d54 | 946 | perf_lock_task_context(struct task_struct *task, int ctxn, unsigned long *flags) |
25346b93 | 947 | { |
cdd6c482 | 948 | struct perf_event_context *ctx; |
25346b93 | 949 | |
9ed6060d | 950 | retry: |
058ebd0e PZ |
951 | /* |
952 | * One of the few rules of preemptible RCU is that one cannot do | |
953 | * rcu_read_unlock() while holding a scheduler (or nested) lock when | |
954 | * part of the read side critical section was preemptible -- see | |
955 | * rcu_read_unlock_special(). | |
956 | * | |
957 | * Since ctx->lock nests under rq->lock we must ensure the entire read | |
958 | * side critical section is non-preemptible. | |
959 | */ | |
960 | preempt_disable(); | |
961 | rcu_read_lock(); | |
8dc85d54 | 962 | ctx = rcu_dereference(task->perf_event_ctxp[ctxn]); |
25346b93 PM |
963 | if (ctx) { |
964 | /* | |
965 | * If this context is a clone of another, it might | |
966 | * get swapped for another underneath us by | |
cdd6c482 | 967 | * perf_event_task_sched_out, though the |
25346b93 PM |
968 | * rcu_read_lock() protects us from any context |
969 | * getting freed. Lock the context and check if it | |
970 | * got swapped before we could get the lock, and retry | |
971 | * if so. If we locked the right context, then it | |
972 | * can't get swapped on us any more. | |
973 | */ | |
e625cce1 | 974 | raw_spin_lock_irqsave(&ctx->lock, *flags); |
8dc85d54 | 975 | if (ctx != rcu_dereference(task->perf_event_ctxp[ctxn])) { |
e625cce1 | 976 | raw_spin_unlock_irqrestore(&ctx->lock, *flags); |
058ebd0e PZ |
977 | rcu_read_unlock(); |
978 | preempt_enable(); | |
25346b93 PM |
979 | goto retry; |
980 | } | |
b49a9e7e PZ |
981 | |
982 | if (!atomic_inc_not_zero(&ctx->refcount)) { | |
e625cce1 | 983 | raw_spin_unlock_irqrestore(&ctx->lock, *flags); |
b49a9e7e PZ |
984 | ctx = NULL; |
985 | } | |
25346b93 PM |
986 | } |
987 | rcu_read_unlock(); | |
058ebd0e | 988 | preempt_enable(); |
25346b93 PM |
989 | return ctx; |
990 | } | |
991 | ||
992 | /* | |
993 | * Get the context for a task and increment its pin_count so it | |
994 | * can't get swapped to another task. This also increments its | |
995 | * reference count so that the context can't get freed. | |
996 | */ | |
8dc85d54 PZ |
997 | static struct perf_event_context * |
998 | perf_pin_task_context(struct task_struct *task, int ctxn) | |
25346b93 | 999 | { |
cdd6c482 | 1000 | struct perf_event_context *ctx; |
25346b93 PM |
1001 | unsigned long flags; |
1002 | ||
8dc85d54 | 1003 | ctx = perf_lock_task_context(task, ctxn, &flags); |
25346b93 PM |
1004 | if (ctx) { |
1005 | ++ctx->pin_count; | |
e625cce1 | 1006 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1007 | } |
1008 | return ctx; | |
1009 | } | |
1010 | ||
cdd6c482 | 1011 | static void perf_unpin_context(struct perf_event_context *ctx) |
25346b93 PM |
1012 | { |
1013 | unsigned long flags; | |
1014 | ||
e625cce1 | 1015 | raw_spin_lock_irqsave(&ctx->lock, flags); |
25346b93 | 1016 | --ctx->pin_count; |
e625cce1 | 1017 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1018 | } |
1019 | ||
f67218c3 PZ |
1020 | /* |
1021 | * Update the record of the current time in a context. | |
1022 | */ | |
1023 | static void update_context_time(struct perf_event_context *ctx) | |
1024 | { | |
1025 | u64 now = perf_clock(); | |
1026 | ||
1027 | ctx->time += now - ctx->timestamp; | |
1028 | ctx->timestamp = now; | |
1029 | } | |
1030 | ||
4158755d SE |
1031 | static u64 perf_event_time(struct perf_event *event) |
1032 | { | |
1033 | struct perf_event_context *ctx = event->ctx; | |
e5d1367f SE |
1034 | |
1035 | if (is_cgroup_event(event)) | |
1036 | return perf_cgroup_event_time(event); | |
1037 | ||
4158755d SE |
1038 | return ctx ? ctx->time : 0; |
1039 | } | |
1040 | ||
f67218c3 PZ |
1041 | /* |
1042 | * Update the total_time_enabled and total_time_running fields for a event. | |
b7526f0c | 1043 | * The caller of this function needs to hold the ctx->lock. |
f67218c3 PZ |
1044 | */ |
1045 | static void update_event_times(struct perf_event *event) | |
1046 | { | |
1047 | struct perf_event_context *ctx = event->ctx; | |
1048 | u64 run_end; | |
1049 | ||
1050 | if (event->state < PERF_EVENT_STATE_INACTIVE || | |
1051 | event->group_leader->state < PERF_EVENT_STATE_INACTIVE) | |
1052 | return; | |
e5d1367f SE |
1053 | /* |
1054 | * in cgroup mode, time_enabled represents | |
1055 | * the time the event was enabled AND active | |
1056 | * tasks were in the monitored cgroup. This is | |
1057 | * independent of the activity of the context as | |
1058 | * there may be a mix of cgroup and non-cgroup events. | |
1059 | * | |
1060 | * That is why we treat cgroup events differently | |
1061 | * here. | |
1062 | */ | |
1063 | if (is_cgroup_event(event)) | |
46cd6a7f | 1064 | run_end = perf_cgroup_event_time(event); |
e5d1367f SE |
1065 | else if (ctx->is_active) |
1066 | run_end = ctx->time; | |
acd1d7c1 PZ |
1067 | else |
1068 | run_end = event->tstamp_stopped; | |
1069 | ||
1070 | event->total_time_enabled = run_end - event->tstamp_enabled; | |
f67218c3 PZ |
1071 | |
1072 | if (event->state == PERF_EVENT_STATE_INACTIVE) | |
1073 | run_end = event->tstamp_stopped; | |
1074 | else | |
4158755d | 1075 | run_end = perf_event_time(event); |
f67218c3 PZ |
1076 | |
1077 | event->total_time_running = run_end - event->tstamp_running; | |
e5d1367f | 1078 | |
f67218c3 PZ |
1079 | } |
1080 | ||
96c21a46 PZ |
1081 | /* |
1082 | * Update total_time_enabled and total_time_running for all events in a group. | |
1083 | */ | |
1084 | static void update_group_times(struct perf_event *leader) | |
1085 | { | |
1086 | struct perf_event *event; | |
1087 | ||
1088 | update_event_times(leader); | |
1089 | list_for_each_entry(event, &leader->sibling_list, group_entry) | |
1090 | update_event_times(event); | |
1091 | } | |
1092 | ||
889ff015 FW |
1093 | static struct list_head * |
1094 | ctx_group_list(struct perf_event *event, struct perf_event_context *ctx) | |
1095 | { | |
1096 | if (event->attr.pinned) | |
1097 | return &ctx->pinned_groups; | |
1098 | else | |
1099 | return &ctx->flexible_groups; | |
1100 | } | |
1101 | ||
fccc714b | 1102 | /* |
cdd6c482 | 1103 | * Add a event from the lists for its context. |
fccc714b PZ |
1104 | * Must be called with ctx->mutex and ctx->lock held. |
1105 | */ | |
04289bb9 | 1106 | static void |
cdd6c482 | 1107 | list_add_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1108 | { |
8a49542c PZ |
1109 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); |
1110 | event->attach_state |= PERF_ATTACH_CONTEXT; | |
04289bb9 IM |
1111 | |
1112 | /* | |
8a49542c PZ |
1113 | * If we're a stand alone event or group leader, we go to the context |
1114 | * list, group events are kept attached to the group so that | |
1115 | * perf_group_detach can, at all times, locate all siblings. | |
04289bb9 | 1116 | */ |
8a49542c | 1117 | if (event->group_leader == event) { |
889ff015 FW |
1118 | struct list_head *list; |
1119 | ||
d6f962b5 FW |
1120 | if (is_software_event(event)) |
1121 | event->group_flags |= PERF_GROUP_SOFTWARE; | |
1122 | ||
889ff015 FW |
1123 | list = ctx_group_list(event, ctx); |
1124 | list_add_tail(&event->group_entry, list); | |
5c148194 | 1125 | } |
592903cd | 1126 | |
08309379 | 1127 | if (is_cgroup_event(event)) |
e5d1367f | 1128 | ctx->nr_cgroups++; |
e5d1367f | 1129 | |
d010b332 SE |
1130 | if (has_branch_stack(event)) |
1131 | ctx->nr_branch_stack++; | |
1132 | ||
cdd6c482 | 1133 | list_add_rcu(&event->event_entry, &ctx->event_list); |
b5ab4cd5 | 1134 | if (!ctx->nr_events) |
108b02cf | 1135 | perf_pmu_rotate_start(ctx->pmu); |
cdd6c482 IM |
1136 | ctx->nr_events++; |
1137 | if (event->attr.inherit_stat) | |
bfbd3381 | 1138 | ctx->nr_stat++; |
04289bb9 IM |
1139 | } |
1140 | ||
0231bb53 JO |
1141 | /* |
1142 | * Initialize event state based on the perf_event_attr::disabled. | |
1143 | */ | |
1144 | static inline void perf_event__state_init(struct perf_event *event) | |
1145 | { | |
1146 | event->state = event->attr.disabled ? PERF_EVENT_STATE_OFF : | |
1147 | PERF_EVENT_STATE_INACTIVE; | |
1148 | } | |
1149 | ||
c320c7b7 ACM |
1150 | /* |
1151 | * Called at perf_event creation and when events are attached/detached from a | |
1152 | * group. | |
1153 | */ | |
1154 | static void perf_event__read_size(struct perf_event *event) | |
1155 | { | |
1156 | int entry = sizeof(u64); /* value */ | |
1157 | int size = 0; | |
1158 | int nr = 1; | |
1159 | ||
1160 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
1161 | size += sizeof(u64); | |
1162 | ||
1163 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
1164 | size += sizeof(u64); | |
1165 | ||
1166 | if (event->attr.read_format & PERF_FORMAT_ID) | |
1167 | entry += sizeof(u64); | |
1168 | ||
1169 | if (event->attr.read_format & PERF_FORMAT_GROUP) { | |
1170 | nr += event->group_leader->nr_siblings; | |
1171 | size += sizeof(u64); | |
1172 | } | |
1173 | ||
1174 | size += entry * nr; | |
1175 | event->read_size = size; | |
1176 | } | |
1177 | ||
1178 | static void perf_event__header_size(struct perf_event *event) | |
1179 | { | |
1180 | struct perf_sample_data *data; | |
1181 | u64 sample_type = event->attr.sample_type; | |
1182 | u16 size = 0; | |
1183 | ||
1184 | perf_event__read_size(event); | |
1185 | ||
1186 | if (sample_type & PERF_SAMPLE_IP) | |
1187 | size += sizeof(data->ip); | |
1188 | ||
6844c09d ACM |
1189 | if (sample_type & PERF_SAMPLE_ADDR) |
1190 | size += sizeof(data->addr); | |
1191 | ||
1192 | if (sample_type & PERF_SAMPLE_PERIOD) | |
1193 | size += sizeof(data->period); | |
1194 | ||
c3feedf2 AK |
1195 | if (sample_type & PERF_SAMPLE_WEIGHT) |
1196 | size += sizeof(data->weight); | |
1197 | ||
6844c09d ACM |
1198 | if (sample_type & PERF_SAMPLE_READ) |
1199 | size += event->read_size; | |
1200 | ||
d6be9ad6 SE |
1201 | if (sample_type & PERF_SAMPLE_DATA_SRC) |
1202 | size += sizeof(data->data_src.val); | |
1203 | ||
6844c09d ACM |
1204 | event->header_size = size; |
1205 | } | |
1206 | ||
1207 | static void perf_event__id_header_size(struct perf_event *event) | |
1208 | { | |
1209 | struct perf_sample_data *data; | |
1210 | u64 sample_type = event->attr.sample_type; | |
1211 | u16 size = 0; | |
1212 | ||
c320c7b7 ACM |
1213 | if (sample_type & PERF_SAMPLE_TID) |
1214 | size += sizeof(data->tid_entry); | |
1215 | ||
1216 | if (sample_type & PERF_SAMPLE_TIME) | |
1217 | size += sizeof(data->time); | |
1218 | ||
c320c7b7 ACM |
1219 | if (sample_type & PERF_SAMPLE_ID) |
1220 | size += sizeof(data->id); | |
1221 | ||
1222 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
1223 | size += sizeof(data->stream_id); | |
1224 | ||
1225 | if (sample_type & PERF_SAMPLE_CPU) | |
1226 | size += sizeof(data->cpu_entry); | |
1227 | ||
6844c09d | 1228 | event->id_header_size = size; |
c320c7b7 ACM |
1229 | } |
1230 | ||
8a49542c PZ |
1231 | static void perf_group_attach(struct perf_event *event) |
1232 | { | |
c320c7b7 | 1233 | struct perf_event *group_leader = event->group_leader, *pos; |
8a49542c | 1234 | |
74c3337c PZ |
1235 | /* |
1236 | * We can have double attach due to group movement in perf_event_open. | |
1237 | */ | |
1238 | if (event->attach_state & PERF_ATTACH_GROUP) | |
1239 | return; | |
1240 | ||
8a49542c PZ |
1241 | event->attach_state |= PERF_ATTACH_GROUP; |
1242 | ||
1243 | if (group_leader == event) | |
1244 | return; | |
1245 | ||
1246 | if (group_leader->group_flags & PERF_GROUP_SOFTWARE && | |
1247 | !is_software_event(event)) | |
1248 | group_leader->group_flags &= ~PERF_GROUP_SOFTWARE; | |
1249 | ||
1250 | list_add_tail(&event->group_entry, &group_leader->sibling_list); | |
1251 | group_leader->nr_siblings++; | |
c320c7b7 ACM |
1252 | |
1253 | perf_event__header_size(group_leader); | |
1254 | ||
1255 | list_for_each_entry(pos, &group_leader->sibling_list, group_entry) | |
1256 | perf_event__header_size(pos); | |
8a49542c PZ |
1257 | } |
1258 | ||
a63eaf34 | 1259 | /* |
cdd6c482 | 1260 | * Remove a event from the lists for its context. |
fccc714b | 1261 | * Must be called with ctx->mutex and ctx->lock held. |
a63eaf34 | 1262 | */ |
04289bb9 | 1263 | static void |
cdd6c482 | 1264 | list_del_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1265 | { |
68cacd29 | 1266 | struct perf_cpu_context *cpuctx; |
8a49542c PZ |
1267 | /* |
1268 | * We can have double detach due to exit/hot-unplug + close. | |
1269 | */ | |
1270 | if (!(event->attach_state & PERF_ATTACH_CONTEXT)) | |
a63eaf34 | 1271 | return; |
8a49542c PZ |
1272 | |
1273 | event->attach_state &= ~PERF_ATTACH_CONTEXT; | |
1274 | ||
68cacd29 | 1275 | if (is_cgroup_event(event)) { |
e5d1367f | 1276 | ctx->nr_cgroups--; |
68cacd29 SE |
1277 | cpuctx = __get_cpu_context(ctx); |
1278 | /* | |
1279 | * if there are no more cgroup events | |
1280 | * then cler cgrp to avoid stale pointer | |
1281 | * in update_cgrp_time_from_cpuctx() | |
1282 | */ | |
1283 | if (!ctx->nr_cgroups) | |
1284 | cpuctx->cgrp = NULL; | |
1285 | } | |
e5d1367f | 1286 | |
d010b332 SE |
1287 | if (has_branch_stack(event)) |
1288 | ctx->nr_branch_stack--; | |
1289 | ||
cdd6c482 IM |
1290 | ctx->nr_events--; |
1291 | if (event->attr.inherit_stat) | |
bfbd3381 | 1292 | ctx->nr_stat--; |
8bc20959 | 1293 | |
cdd6c482 | 1294 | list_del_rcu(&event->event_entry); |
04289bb9 | 1295 | |
8a49542c PZ |
1296 | if (event->group_leader == event) |
1297 | list_del_init(&event->group_entry); | |
5c148194 | 1298 | |
96c21a46 | 1299 | update_group_times(event); |
b2e74a26 SE |
1300 | |
1301 | /* | |
1302 | * If event was in error state, then keep it | |
1303 | * that way, otherwise bogus counts will be | |
1304 | * returned on read(). The only way to get out | |
1305 | * of error state is by explicit re-enabling | |
1306 | * of the event | |
1307 | */ | |
1308 | if (event->state > PERF_EVENT_STATE_OFF) | |
1309 | event->state = PERF_EVENT_STATE_OFF; | |
050735b0 PZ |
1310 | } |
1311 | ||
8a49542c | 1312 | static void perf_group_detach(struct perf_event *event) |
050735b0 PZ |
1313 | { |
1314 | struct perf_event *sibling, *tmp; | |
8a49542c PZ |
1315 | struct list_head *list = NULL; |
1316 | ||
1317 | /* | |
1318 | * We can have double detach due to exit/hot-unplug + close. | |
1319 | */ | |
1320 | if (!(event->attach_state & PERF_ATTACH_GROUP)) | |
1321 | return; | |
1322 | ||
1323 | event->attach_state &= ~PERF_ATTACH_GROUP; | |
1324 | ||
1325 | /* | |
1326 | * If this is a sibling, remove it from its group. | |
1327 | */ | |
1328 | if (event->group_leader != event) { | |
1329 | list_del_init(&event->group_entry); | |
1330 | event->group_leader->nr_siblings--; | |
c320c7b7 | 1331 | goto out; |
8a49542c PZ |
1332 | } |
1333 | ||
1334 | if (!list_empty(&event->group_entry)) | |
1335 | list = &event->group_entry; | |
2e2af50b | 1336 | |
04289bb9 | 1337 | /* |
cdd6c482 IM |
1338 | * If this was a group event with sibling events then |
1339 | * upgrade the siblings to singleton events by adding them | |
8a49542c | 1340 | * to whatever list we are on. |
04289bb9 | 1341 | */ |
cdd6c482 | 1342 | list_for_each_entry_safe(sibling, tmp, &event->sibling_list, group_entry) { |
8a49542c PZ |
1343 | if (list) |
1344 | list_move_tail(&sibling->group_entry, list); | |
04289bb9 | 1345 | sibling->group_leader = sibling; |
d6f962b5 FW |
1346 | |
1347 | /* Inherit group flags from the previous leader */ | |
1348 | sibling->group_flags = event->group_flags; | |
04289bb9 | 1349 | } |
c320c7b7 ACM |
1350 | |
1351 | out: | |
1352 | perf_event__header_size(event->group_leader); | |
1353 | ||
1354 | list_for_each_entry(tmp, &event->group_leader->sibling_list, group_entry) | |
1355 | perf_event__header_size(tmp); | |
04289bb9 IM |
1356 | } |
1357 | ||
fa66f07a SE |
1358 | static inline int |
1359 | event_filter_match(struct perf_event *event) | |
1360 | { | |
e5d1367f SE |
1361 | return (event->cpu == -1 || event->cpu == smp_processor_id()) |
1362 | && perf_cgroup_match(event); | |
fa66f07a SE |
1363 | } |
1364 | ||
9ffcfa6f SE |
1365 | static void |
1366 | event_sched_out(struct perf_event *event, | |
3b6f9e5c | 1367 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 1368 | struct perf_event_context *ctx) |
3b6f9e5c | 1369 | { |
4158755d | 1370 | u64 tstamp = perf_event_time(event); |
fa66f07a SE |
1371 | u64 delta; |
1372 | /* | |
1373 | * An event which could not be activated because of | |
1374 | * filter mismatch still needs to have its timings | |
1375 | * maintained, otherwise bogus information is return | |
1376 | * via read() for time_enabled, time_running: | |
1377 | */ | |
1378 | if (event->state == PERF_EVENT_STATE_INACTIVE | |
1379 | && !event_filter_match(event)) { | |
e5d1367f | 1380 | delta = tstamp - event->tstamp_stopped; |
fa66f07a | 1381 | event->tstamp_running += delta; |
4158755d | 1382 | event->tstamp_stopped = tstamp; |
fa66f07a SE |
1383 | } |
1384 | ||
cdd6c482 | 1385 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
9ffcfa6f | 1386 | return; |
3b6f9e5c | 1387 | |
cdd6c482 IM |
1388 | event->state = PERF_EVENT_STATE_INACTIVE; |
1389 | if (event->pending_disable) { | |
1390 | event->pending_disable = 0; | |
1391 | event->state = PERF_EVENT_STATE_OFF; | |
970892a9 | 1392 | } |
4158755d | 1393 | event->tstamp_stopped = tstamp; |
a4eaf7f1 | 1394 | event->pmu->del(event, 0); |
cdd6c482 | 1395 | event->oncpu = -1; |
3b6f9e5c | 1396 | |
cdd6c482 | 1397 | if (!is_software_event(event)) |
3b6f9e5c PM |
1398 | cpuctx->active_oncpu--; |
1399 | ctx->nr_active--; | |
0f5a2601 PZ |
1400 | if (event->attr.freq && event->attr.sample_freq) |
1401 | ctx->nr_freq--; | |
cdd6c482 | 1402 | if (event->attr.exclusive || !cpuctx->active_oncpu) |
3b6f9e5c PM |
1403 | cpuctx->exclusive = 0; |
1404 | } | |
1405 | ||
d859e29f | 1406 | static void |
cdd6c482 | 1407 | group_sched_out(struct perf_event *group_event, |
d859e29f | 1408 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 1409 | struct perf_event_context *ctx) |
d859e29f | 1410 | { |
cdd6c482 | 1411 | struct perf_event *event; |
fa66f07a | 1412 | int state = group_event->state; |
d859e29f | 1413 | |
cdd6c482 | 1414 | event_sched_out(group_event, cpuctx, ctx); |
d859e29f PM |
1415 | |
1416 | /* | |
1417 | * Schedule out siblings (if any): | |
1418 | */ | |
cdd6c482 IM |
1419 | list_for_each_entry(event, &group_event->sibling_list, group_entry) |
1420 | event_sched_out(event, cpuctx, ctx); | |
d859e29f | 1421 | |
fa66f07a | 1422 | if (state == PERF_EVENT_STATE_ACTIVE && group_event->attr.exclusive) |
d859e29f PM |
1423 | cpuctx->exclusive = 0; |
1424 | } | |
1425 | ||
0793a61d | 1426 | /* |
cdd6c482 | 1427 | * Cross CPU call to remove a performance event |
0793a61d | 1428 | * |
cdd6c482 | 1429 | * We disable the event on the hardware level first. After that we |
0793a61d TG |
1430 | * remove it from the context list. |
1431 | */ | |
fe4b04fa | 1432 | static int __perf_remove_from_context(void *info) |
0793a61d | 1433 | { |
cdd6c482 IM |
1434 | struct perf_event *event = info; |
1435 | struct perf_event_context *ctx = event->ctx; | |
108b02cf | 1436 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
0793a61d | 1437 | |
e625cce1 | 1438 | raw_spin_lock(&ctx->lock); |
cdd6c482 | 1439 | event_sched_out(event, cpuctx, ctx); |
cdd6c482 | 1440 | list_del_event(event, ctx); |
64ce3126 PZ |
1441 | if (!ctx->nr_events && cpuctx->task_ctx == ctx) { |
1442 | ctx->is_active = 0; | |
1443 | cpuctx->task_ctx = NULL; | |
1444 | } | |
e625cce1 | 1445 | raw_spin_unlock(&ctx->lock); |
fe4b04fa PZ |
1446 | |
1447 | return 0; | |
0793a61d TG |
1448 | } |
1449 | ||
1450 | ||
1451 | /* | |
cdd6c482 | 1452 | * Remove the event from a task's (or a CPU's) list of events. |
0793a61d | 1453 | * |
cdd6c482 | 1454 | * CPU events are removed with a smp call. For task events we only |
0793a61d | 1455 | * call when the task is on a CPU. |
c93f7669 | 1456 | * |
cdd6c482 IM |
1457 | * If event->ctx is a cloned context, callers must make sure that |
1458 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 PM |
1459 | * remains valid. This is OK when called from perf_release since |
1460 | * that only calls us on the top-level context, which can't be a clone. | |
cdd6c482 | 1461 | * When called from perf_event_exit_task, it's OK because the |
c93f7669 | 1462 | * context has been detached from its task. |
0793a61d | 1463 | */ |
fe4b04fa | 1464 | static void perf_remove_from_context(struct perf_event *event) |
0793a61d | 1465 | { |
cdd6c482 | 1466 | struct perf_event_context *ctx = event->ctx; |
0793a61d TG |
1467 | struct task_struct *task = ctx->task; |
1468 | ||
fe4b04fa PZ |
1469 | lockdep_assert_held(&ctx->mutex); |
1470 | ||
0793a61d TG |
1471 | if (!task) { |
1472 | /* | |
cdd6c482 | 1473 | * Per cpu events are removed via an smp call and |
af901ca1 | 1474 | * the removal is always successful. |
0793a61d | 1475 | */ |
fe4b04fa | 1476 | cpu_function_call(event->cpu, __perf_remove_from_context, event); |
0793a61d TG |
1477 | return; |
1478 | } | |
1479 | ||
1480 | retry: | |
fe4b04fa PZ |
1481 | if (!task_function_call(task, __perf_remove_from_context, event)) |
1482 | return; | |
0793a61d | 1483 | |
e625cce1 | 1484 | raw_spin_lock_irq(&ctx->lock); |
0793a61d | 1485 | /* |
fe4b04fa PZ |
1486 | * If we failed to find a running task, but find the context active now |
1487 | * that we've acquired the ctx->lock, retry. | |
0793a61d | 1488 | */ |
fe4b04fa | 1489 | if (ctx->is_active) { |
e625cce1 | 1490 | raw_spin_unlock_irq(&ctx->lock); |
0793a61d TG |
1491 | goto retry; |
1492 | } | |
1493 | ||
1494 | /* | |
fe4b04fa PZ |
1495 | * Since the task isn't running, its safe to remove the event, us |
1496 | * holding the ctx->lock ensures the task won't get scheduled in. | |
0793a61d | 1497 | */ |
fe4b04fa | 1498 | list_del_event(event, ctx); |
e625cce1 | 1499 | raw_spin_unlock_irq(&ctx->lock); |
0793a61d TG |
1500 | } |
1501 | ||
d859e29f | 1502 | /* |
cdd6c482 | 1503 | * Cross CPU call to disable a performance event |
d859e29f | 1504 | */ |
500ad2d8 | 1505 | int __perf_event_disable(void *info) |
d859e29f | 1506 | { |
cdd6c482 | 1507 | struct perf_event *event = info; |
cdd6c482 | 1508 | struct perf_event_context *ctx = event->ctx; |
108b02cf | 1509 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
d859e29f PM |
1510 | |
1511 | /* | |
cdd6c482 IM |
1512 | * If this is a per-task event, need to check whether this |
1513 | * event's task is the current task on this cpu. | |
fe4b04fa PZ |
1514 | * |
1515 | * Can trigger due to concurrent perf_event_context_sched_out() | |
1516 | * flipping contexts around. | |
d859e29f | 1517 | */ |
665c2142 | 1518 | if (ctx->task && cpuctx->task_ctx != ctx) |
fe4b04fa | 1519 | return -EINVAL; |
d859e29f | 1520 | |
e625cce1 | 1521 | raw_spin_lock(&ctx->lock); |
d859e29f PM |
1522 | |
1523 | /* | |
cdd6c482 | 1524 | * If the event is on, turn it off. |
d859e29f PM |
1525 | * If it is in error state, leave it in error state. |
1526 | */ | |
cdd6c482 | 1527 | if (event->state >= PERF_EVENT_STATE_INACTIVE) { |
4af4998b | 1528 | update_context_time(ctx); |
e5d1367f | 1529 | update_cgrp_time_from_event(event); |
cdd6c482 IM |
1530 | update_group_times(event); |
1531 | if (event == event->group_leader) | |
1532 | group_sched_out(event, cpuctx, ctx); | |
d859e29f | 1533 | else |
cdd6c482 IM |
1534 | event_sched_out(event, cpuctx, ctx); |
1535 | event->state = PERF_EVENT_STATE_OFF; | |
d859e29f PM |
1536 | } |
1537 | ||
e625cce1 | 1538 | raw_spin_unlock(&ctx->lock); |
fe4b04fa PZ |
1539 | |
1540 | return 0; | |
d859e29f PM |
1541 | } |
1542 | ||
1543 | /* | |
cdd6c482 | 1544 | * Disable a event. |
c93f7669 | 1545 | * |
cdd6c482 IM |
1546 | * If event->ctx is a cloned context, callers must make sure that |
1547 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 1548 | * remains valid. This condition is satisifed when called through |
cdd6c482 IM |
1549 | * perf_event_for_each_child or perf_event_for_each because they |
1550 | * hold the top-level event's child_mutex, so any descendant that | |
1551 | * goes to exit will block in sync_child_event. | |
1552 | * When called from perf_pending_event it's OK because event->ctx | |
c93f7669 | 1553 | * is the current context on this CPU and preemption is disabled, |
cdd6c482 | 1554 | * hence we can't get into perf_event_task_sched_out for this context. |
d859e29f | 1555 | */ |
44234adc | 1556 | void perf_event_disable(struct perf_event *event) |
d859e29f | 1557 | { |
cdd6c482 | 1558 | struct perf_event_context *ctx = event->ctx; |
d859e29f PM |
1559 | struct task_struct *task = ctx->task; |
1560 | ||
1561 | if (!task) { | |
1562 | /* | |
cdd6c482 | 1563 | * Disable the event on the cpu that it's on |
d859e29f | 1564 | */ |
fe4b04fa | 1565 | cpu_function_call(event->cpu, __perf_event_disable, event); |
d859e29f PM |
1566 | return; |
1567 | } | |
1568 | ||
9ed6060d | 1569 | retry: |
fe4b04fa PZ |
1570 | if (!task_function_call(task, __perf_event_disable, event)) |
1571 | return; | |
d859e29f | 1572 | |
e625cce1 | 1573 | raw_spin_lock_irq(&ctx->lock); |
d859e29f | 1574 | /* |
cdd6c482 | 1575 | * If the event is still active, we need to retry the cross-call. |
d859e29f | 1576 | */ |
cdd6c482 | 1577 | if (event->state == PERF_EVENT_STATE_ACTIVE) { |
e625cce1 | 1578 | raw_spin_unlock_irq(&ctx->lock); |
fe4b04fa PZ |
1579 | /* |
1580 | * Reload the task pointer, it might have been changed by | |
1581 | * a concurrent perf_event_context_sched_out(). | |
1582 | */ | |
1583 | task = ctx->task; | |
d859e29f PM |
1584 | goto retry; |
1585 | } | |
1586 | ||
1587 | /* | |
1588 | * Since we have the lock this context can't be scheduled | |
1589 | * in, so we can change the state safely. | |
1590 | */ | |
cdd6c482 IM |
1591 | if (event->state == PERF_EVENT_STATE_INACTIVE) { |
1592 | update_group_times(event); | |
1593 | event->state = PERF_EVENT_STATE_OFF; | |
53cfbf59 | 1594 | } |
e625cce1 | 1595 | raw_spin_unlock_irq(&ctx->lock); |
d859e29f | 1596 | } |
dcfce4a0 | 1597 | EXPORT_SYMBOL_GPL(perf_event_disable); |
d859e29f | 1598 | |
e5d1367f SE |
1599 | static void perf_set_shadow_time(struct perf_event *event, |
1600 | struct perf_event_context *ctx, | |
1601 | u64 tstamp) | |
1602 | { | |
1603 | /* | |
1604 | * use the correct time source for the time snapshot | |
1605 | * | |
1606 | * We could get by without this by leveraging the | |
1607 | * fact that to get to this function, the caller | |
1608 | * has most likely already called update_context_time() | |
1609 | * and update_cgrp_time_xx() and thus both timestamp | |
1610 | * are identical (or very close). Given that tstamp is, | |
1611 | * already adjusted for cgroup, we could say that: | |
1612 | * tstamp - ctx->timestamp | |
1613 | * is equivalent to | |
1614 | * tstamp - cgrp->timestamp. | |
1615 | * | |
1616 | * Then, in perf_output_read(), the calculation would | |
1617 | * work with no changes because: | |
1618 | * - event is guaranteed scheduled in | |
1619 | * - no scheduled out in between | |
1620 | * - thus the timestamp would be the same | |
1621 | * | |
1622 | * But this is a bit hairy. | |
1623 | * | |
1624 | * So instead, we have an explicit cgroup call to remain | |
1625 | * within the time time source all along. We believe it | |
1626 | * is cleaner and simpler to understand. | |
1627 | */ | |
1628 | if (is_cgroup_event(event)) | |
1629 | perf_cgroup_set_shadow_time(event, tstamp); | |
1630 | else | |
1631 | event->shadow_ctx_time = tstamp - ctx->timestamp; | |
1632 | } | |
1633 | ||
4fe757dd PZ |
1634 | #define MAX_INTERRUPTS (~0ULL) |
1635 | ||
1636 | static void perf_log_throttle(struct perf_event *event, int enable); | |
1637 | ||
235c7fc7 | 1638 | static int |
9ffcfa6f | 1639 | event_sched_in(struct perf_event *event, |
235c7fc7 | 1640 | struct perf_cpu_context *cpuctx, |
6e37738a | 1641 | struct perf_event_context *ctx) |
235c7fc7 | 1642 | { |
4158755d SE |
1643 | u64 tstamp = perf_event_time(event); |
1644 | ||
cdd6c482 | 1645 | if (event->state <= PERF_EVENT_STATE_OFF) |
235c7fc7 IM |
1646 | return 0; |
1647 | ||
cdd6c482 | 1648 | event->state = PERF_EVENT_STATE_ACTIVE; |
6e37738a | 1649 | event->oncpu = smp_processor_id(); |
4fe757dd PZ |
1650 | |
1651 | /* | |
1652 | * Unthrottle events, since we scheduled we might have missed several | |
1653 | * ticks already, also for a heavily scheduling task there is little | |
1654 | * guarantee it'll get a tick in a timely manner. | |
1655 | */ | |
1656 | if (unlikely(event->hw.interrupts == MAX_INTERRUPTS)) { | |
1657 | perf_log_throttle(event, 1); | |
1658 | event->hw.interrupts = 0; | |
1659 | } | |
1660 | ||
235c7fc7 IM |
1661 | /* |
1662 | * The new state must be visible before we turn it on in the hardware: | |
1663 | */ | |
1664 | smp_wmb(); | |
1665 | ||
a4eaf7f1 | 1666 | if (event->pmu->add(event, PERF_EF_START)) { |
cdd6c482 IM |
1667 | event->state = PERF_EVENT_STATE_INACTIVE; |
1668 | event->oncpu = -1; | |
235c7fc7 IM |
1669 | return -EAGAIN; |
1670 | } | |
1671 | ||
4158755d | 1672 | event->tstamp_running += tstamp - event->tstamp_stopped; |
9ffcfa6f | 1673 | |
e5d1367f | 1674 | perf_set_shadow_time(event, ctx, tstamp); |
eed01528 | 1675 | |
cdd6c482 | 1676 | if (!is_software_event(event)) |
3b6f9e5c | 1677 | cpuctx->active_oncpu++; |
235c7fc7 | 1678 | ctx->nr_active++; |
0f5a2601 PZ |
1679 | if (event->attr.freq && event->attr.sample_freq) |
1680 | ctx->nr_freq++; | |
235c7fc7 | 1681 | |
cdd6c482 | 1682 | if (event->attr.exclusive) |
3b6f9e5c PM |
1683 | cpuctx->exclusive = 1; |
1684 | ||
235c7fc7 IM |
1685 | return 0; |
1686 | } | |
1687 | ||
6751b71e | 1688 | static int |
cdd6c482 | 1689 | group_sched_in(struct perf_event *group_event, |
6751b71e | 1690 | struct perf_cpu_context *cpuctx, |
6e37738a | 1691 | struct perf_event_context *ctx) |
6751b71e | 1692 | { |
6bde9b6c | 1693 | struct perf_event *event, *partial_group = NULL; |
51b0fe39 | 1694 | struct pmu *pmu = group_event->pmu; |
d7842da4 SE |
1695 | u64 now = ctx->time; |
1696 | bool simulate = false; | |
6751b71e | 1697 | |
cdd6c482 | 1698 | if (group_event->state == PERF_EVENT_STATE_OFF) |
6751b71e PM |
1699 | return 0; |
1700 | ||
ad5133b7 | 1701 | pmu->start_txn(pmu); |
6bde9b6c | 1702 | |
9ffcfa6f | 1703 | if (event_sched_in(group_event, cpuctx, ctx)) { |
ad5133b7 | 1704 | pmu->cancel_txn(pmu); |
9e630205 | 1705 | perf_cpu_hrtimer_restart(cpuctx); |
6751b71e | 1706 | return -EAGAIN; |
90151c35 | 1707 | } |
6751b71e PM |
1708 | |
1709 | /* | |
1710 | * Schedule in siblings as one group (if any): | |
1711 | */ | |
cdd6c482 | 1712 | list_for_each_entry(event, &group_event->sibling_list, group_entry) { |
9ffcfa6f | 1713 | if (event_sched_in(event, cpuctx, ctx)) { |
cdd6c482 | 1714 | partial_group = event; |
6751b71e PM |
1715 | goto group_error; |
1716 | } | |
1717 | } | |
1718 | ||
9ffcfa6f | 1719 | if (!pmu->commit_txn(pmu)) |
6e85158c | 1720 | return 0; |
9ffcfa6f | 1721 | |
6751b71e PM |
1722 | group_error: |
1723 | /* | |
1724 | * Groups can be scheduled in as one unit only, so undo any | |
1725 | * partial group before returning: | |
d7842da4 SE |
1726 | * The events up to the failed event are scheduled out normally, |
1727 | * tstamp_stopped will be updated. | |
1728 | * | |
1729 | * The failed events and the remaining siblings need to have | |
1730 | * their timings updated as if they had gone thru event_sched_in() | |
1731 | * and event_sched_out(). This is required to get consistent timings | |
1732 | * across the group. This also takes care of the case where the group | |
1733 | * could never be scheduled by ensuring tstamp_stopped is set to mark | |
1734 | * the time the event was actually stopped, such that time delta | |
1735 | * calculation in update_event_times() is correct. | |
6751b71e | 1736 | */ |
cdd6c482 IM |
1737 | list_for_each_entry(event, &group_event->sibling_list, group_entry) { |
1738 | if (event == partial_group) | |
d7842da4 SE |
1739 | simulate = true; |
1740 | ||
1741 | if (simulate) { | |
1742 | event->tstamp_running += now - event->tstamp_stopped; | |
1743 | event->tstamp_stopped = now; | |
1744 | } else { | |
1745 | event_sched_out(event, cpuctx, ctx); | |
1746 | } | |
6751b71e | 1747 | } |
9ffcfa6f | 1748 | event_sched_out(group_event, cpuctx, ctx); |
6751b71e | 1749 | |
ad5133b7 | 1750 | pmu->cancel_txn(pmu); |
90151c35 | 1751 | |
9e630205 SE |
1752 | perf_cpu_hrtimer_restart(cpuctx); |
1753 | ||
6751b71e PM |
1754 | return -EAGAIN; |
1755 | } | |
1756 | ||
3b6f9e5c | 1757 | /* |
cdd6c482 | 1758 | * Work out whether we can put this event group on the CPU now. |
3b6f9e5c | 1759 | */ |
cdd6c482 | 1760 | static int group_can_go_on(struct perf_event *event, |
3b6f9e5c PM |
1761 | struct perf_cpu_context *cpuctx, |
1762 | int can_add_hw) | |
1763 | { | |
1764 | /* | |
cdd6c482 | 1765 | * Groups consisting entirely of software events can always go on. |
3b6f9e5c | 1766 | */ |
d6f962b5 | 1767 | if (event->group_flags & PERF_GROUP_SOFTWARE) |
3b6f9e5c PM |
1768 | return 1; |
1769 | /* | |
1770 | * If an exclusive group is already on, no other hardware | |
cdd6c482 | 1771 | * events can go on. |
3b6f9e5c PM |
1772 | */ |
1773 | if (cpuctx->exclusive) | |
1774 | return 0; | |
1775 | /* | |
1776 | * If this group is exclusive and there are already | |
cdd6c482 | 1777 | * events on the CPU, it can't go on. |
3b6f9e5c | 1778 | */ |
cdd6c482 | 1779 | if (event->attr.exclusive && cpuctx->active_oncpu) |
3b6f9e5c PM |
1780 | return 0; |
1781 | /* | |
1782 | * Otherwise, try to add it if all previous groups were able | |
1783 | * to go on. | |
1784 | */ | |
1785 | return can_add_hw; | |
1786 | } | |
1787 | ||
cdd6c482 IM |
1788 | static void add_event_to_ctx(struct perf_event *event, |
1789 | struct perf_event_context *ctx) | |
53cfbf59 | 1790 | { |
4158755d SE |
1791 | u64 tstamp = perf_event_time(event); |
1792 | ||
cdd6c482 | 1793 | list_add_event(event, ctx); |
8a49542c | 1794 | perf_group_attach(event); |
4158755d SE |
1795 | event->tstamp_enabled = tstamp; |
1796 | event->tstamp_running = tstamp; | |
1797 | event->tstamp_stopped = tstamp; | |
53cfbf59 PM |
1798 | } |
1799 | ||
2c29ef0f PZ |
1800 | static void task_ctx_sched_out(struct perf_event_context *ctx); |
1801 | static void | |
1802 | ctx_sched_in(struct perf_event_context *ctx, | |
1803 | struct perf_cpu_context *cpuctx, | |
1804 | enum event_type_t event_type, | |
1805 | struct task_struct *task); | |
fe4b04fa | 1806 | |
dce5855b PZ |
1807 | static void perf_event_sched_in(struct perf_cpu_context *cpuctx, |
1808 | struct perf_event_context *ctx, | |
1809 | struct task_struct *task) | |
1810 | { | |
1811 | cpu_ctx_sched_in(cpuctx, EVENT_PINNED, task); | |
1812 | if (ctx) | |
1813 | ctx_sched_in(ctx, cpuctx, EVENT_PINNED, task); | |
1814 | cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE, task); | |
1815 | if (ctx) | |
1816 | ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE, task); | |
1817 | } | |
1818 | ||
0793a61d | 1819 | /* |
cdd6c482 | 1820 | * Cross CPU call to install and enable a performance event |
682076ae PZ |
1821 | * |
1822 | * Must be called with ctx->mutex held | |
0793a61d | 1823 | */ |
fe4b04fa | 1824 | static int __perf_install_in_context(void *info) |
0793a61d | 1825 | { |
cdd6c482 IM |
1826 | struct perf_event *event = info; |
1827 | struct perf_event_context *ctx = event->ctx; | |
108b02cf | 1828 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
2c29ef0f PZ |
1829 | struct perf_event_context *task_ctx = cpuctx->task_ctx; |
1830 | struct task_struct *task = current; | |
1831 | ||
b58f6b0d | 1832 | perf_ctx_lock(cpuctx, task_ctx); |
2c29ef0f | 1833 | perf_pmu_disable(cpuctx->ctx.pmu); |
0793a61d TG |
1834 | |
1835 | /* | |
2c29ef0f | 1836 | * If there was an active task_ctx schedule it out. |
0793a61d | 1837 | */ |
b58f6b0d | 1838 | if (task_ctx) |
2c29ef0f | 1839 | task_ctx_sched_out(task_ctx); |
b58f6b0d PZ |
1840 | |
1841 | /* | |
1842 | * If the context we're installing events in is not the | |
1843 | * active task_ctx, flip them. | |
1844 | */ | |
1845 | if (ctx->task && task_ctx != ctx) { | |
1846 | if (task_ctx) | |
1847 | raw_spin_unlock(&task_ctx->lock); | |
1848 | raw_spin_lock(&ctx->lock); | |
1849 | task_ctx = ctx; | |
1850 | } | |
1851 | ||
1852 | if (task_ctx) { | |
1853 | cpuctx->task_ctx = task_ctx; | |
2c29ef0f PZ |
1854 | task = task_ctx->task; |
1855 | } | |
b58f6b0d | 1856 | |
2c29ef0f | 1857 | cpu_ctx_sched_out(cpuctx, EVENT_ALL); |
0793a61d | 1858 | |
4af4998b | 1859 | update_context_time(ctx); |
e5d1367f SE |
1860 | /* |
1861 | * update cgrp time only if current cgrp | |
1862 | * matches event->cgrp. Must be done before | |
1863 | * calling add_event_to_ctx() | |
1864 | */ | |
1865 | update_cgrp_time_from_event(event); | |
0793a61d | 1866 | |
cdd6c482 | 1867 | add_event_to_ctx(event, ctx); |
0793a61d | 1868 | |
d859e29f | 1869 | /* |
2c29ef0f | 1870 | * Schedule everything back in |
d859e29f | 1871 | */ |
dce5855b | 1872 | perf_event_sched_in(cpuctx, task_ctx, task); |
2c29ef0f PZ |
1873 | |
1874 | perf_pmu_enable(cpuctx->ctx.pmu); | |
1875 | perf_ctx_unlock(cpuctx, task_ctx); | |
fe4b04fa PZ |
1876 | |
1877 | return 0; | |
0793a61d TG |
1878 | } |
1879 | ||
1880 | /* | |
cdd6c482 | 1881 | * Attach a performance event to a context |
0793a61d | 1882 | * |
cdd6c482 IM |
1883 | * First we add the event to the list with the hardware enable bit |
1884 | * in event->hw_config cleared. | |
0793a61d | 1885 | * |
cdd6c482 | 1886 | * If the event is attached to a task which is on a CPU we use a smp |
0793a61d TG |
1887 | * call to enable it in the task context. The task might have been |
1888 | * scheduled away, but we check this in the smp call again. | |
1889 | */ | |
1890 | static void | |
cdd6c482 IM |
1891 | perf_install_in_context(struct perf_event_context *ctx, |
1892 | struct perf_event *event, | |
0793a61d TG |
1893 | int cpu) |
1894 | { | |
1895 | struct task_struct *task = ctx->task; | |
1896 | ||
fe4b04fa PZ |
1897 | lockdep_assert_held(&ctx->mutex); |
1898 | ||
c3f00c70 | 1899 | event->ctx = ctx; |
0cda4c02 YZ |
1900 | if (event->cpu != -1) |
1901 | event->cpu = cpu; | |
c3f00c70 | 1902 | |
0793a61d TG |
1903 | if (!task) { |
1904 | /* | |
cdd6c482 | 1905 | * Per cpu events are installed via an smp call and |
af901ca1 | 1906 | * the install is always successful. |
0793a61d | 1907 | */ |
fe4b04fa | 1908 | cpu_function_call(cpu, __perf_install_in_context, event); |
0793a61d TG |
1909 | return; |
1910 | } | |
1911 | ||
0793a61d | 1912 | retry: |
fe4b04fa PZ |
1913 | if (!task_function_call(task, __perf_install_in_context, event)) |
1914 | return; | |
0793a61d | 1915 | |
e625cce1 | 1916 | raw_spin_lock_irq(&ctx->lock); |
0793a61d | 1917 | /* |
fe4b04fa PZ |
1918 | * If we failed to find a running task, but find the context active now |
1919 | * that we've acquired the ctx->lock, retry. | |
0793a61d | 1920 | */ |
fe4b04fa | 1921 | if (ctx->is_active) { |
e625cce1 | 1922 | raw_spin_unlock_irq(&ctx->lock); |
0793a61d TG |
1923 | goto retry; |
1924 | } | |
1925 | ||
1926 | /* | |
fe4b04fa PZ |
1927 | * Since the task isn't running, its safe to add the event, us holding |
1928 | * the ctx->lock ensures the task won't get scheduled in. | |
0793a61d | 1929 | */ |
fe4b04fa | 1930 | add_event_to_ctx(event, ctx); |
e625cce1 | 1931 | raw_spin_unlock_irq(&ctx->lock); |
0793a61d TG |
1932 | } |
1933 | ||
fa289bec | 1934 | /* |
cdd6c482 | 1935 | * Put a event into inactive state and update time fields. |
fa289bec PM |
1936 | * Enabling the leader of a group effectively enables all |
1937 | * the group members that aren't explicitly disabled, so we | |
1938 | * have to update their ->tstamp_enabled also. | |
1939 | * Note: this works for group members as well as group leaders | |
1940 | * since the non-leader members' sibling_lists will be empty. | |
1941 | */ | |
1d9b482e | 1942 | static void __perf_event_mark_enabled(struct perf_event *event) |
fa289bec | 1943 | { |
cdd6c482 | 1944 | struct perf_event *sub; |
4158755d | 1945 | u64 tstamp = perf_event_time(event); |
fa289bec | 1946 | |
cdd6c482 | 1947 | event->state = PERF_EVENT_STATE_INACTIVE; |
4158755d | 1948 | event->tstamp_enabled = tstamp - event->total_time_enabled; |
9ed6060d | 1949 | list_for_each_entry(sub, &event->sibling_list, group_entry) { |
4158755d SE |
1950 | if (sub->state >= PERF_EVENT_STATE_INACTIVE) |
1951 | sub->tstamp_enabled = tstamp - sub->total_time_enabled; | |
9ed6060d | 1952 | } |
fa289bec PM |
1953 | } |
1954 | ||
d859e29f | 1955 | /* |
cdd6c482 | 1956 | * Cross CPU call to enable a performance event |
d859e29f | 1957 | */ |
fe4b04fa | 1958 | static int __perf_event_enable(void *info) |
04289bb9 | 1959 | { |
cdd6c482 | 1960 | struct perf_event *event = info; |
cdd6c482 IM |
1961 | struct perf_event_context *ctx = event->ctx; |
1962 | struct perf_event *leader = event->group_leader; | |
108b02cf | 1963 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
d859e29f | 1964 | int err; |
04289bb9 | 1965 | |
06f41796 JO |
1966 | /* |
1967 | * There's a time window between 'ctx->is_active' check | |
1968 | * in perf_event_enable function and this place having: | |
1969 | * - IRQs on | |
1970 | * - ctx->lock unlocked | |
1971 | * | |
1972 | * where the task could be killed and 'ctx' deactivated | |
1973 | * by perf_event_exit_task. | |
1974 | */ | |
1975 | if (!ctx->is_active) | |
fe4b04fa | 1976 | return -EINVAL; |
3cbed429 | 1977 | |
e625cce1 | 1978 | raw_spin_lock(&ctx->lock); |
4af4998b | 1979 | update_context_time(ctx); |
d859e29f | 1980 | |
cdd6c482 | 1981 | if (event->state >= PERF_EVENT_STATE_INACTIVE) |
d859e29f | 1982 | goto unlock; |
e5d1367f SE |
1983 | |
1984 | /* | |
1985 | * set current task's cgroup time reference point | |
1986 | */ | |
3f7cce3c | 1987 | perf_cgroup_set_timestamp(current, ctx); |
e5d1367f | 1988 | |
1d9b482e | 1989 | __perf_event_mark_enabled(event); |
04289bb9 | 1990 | |
e5d1367f SE |
1991 | if (!event_filter_match(event)) { |
1992 | if (is_cgroup_event(event)) | |
1993 | perf_cgroup_defer_enabled(event); | |
f4c4176f | 1994 | goto unlock; |
e5d1367f | 1995 | } |
f4c4176f | 1996 | |
04289bb9 | 1997 | /* |
cdd6c482 | 1998 | * If the event is in a group and isn't the group leader, |
d859e29f | 1999 | * then don't put it on unless the group is on. |
04289bb9 | 2000 | */ |
cdd6c482 | 2001 | if (leader != event && leader->state != PERF_EVENT_STATE_ACTIVE) |
d859e29f | 2002 | goto unlock; |
3b6f9e5c | 2003 | |
cdd6c482 | 2004 | if (!group_can_go_on(event, cpuctx, 1)) { |
d859e29f | 2005 | err = -EEXIST; |
e758a33d | 2006 | } else { |
cdd6c482 | 2007 | if (event == leader) |
6e37738a | 2008 | err = group_sched_in(event, cpuctx, ctx); |
e758a33d | 2009 | else |
6e37738a | 2010 | err = event_sched_in(event, cpuctx, ctx); |
e758a33d | 2011 | } |
d859e29f PM |
2012 | |
2013 | if (err) { | |
2014 | /* | |
cdd6c482 | 2015 | * If this event can't go on and it's part of a |
d859e29f PM |
2016 | * group, then the whole group has to come off. |
2017 | */ | |
9e630205 | 2018 | if (leader != event) { |
d859e29f | 2019 | group_sched_out(leader, cpuctx, ctx); |
9e630205 SE |
2020 | perf_cpu_hrtimer_restart(cpuctx); |
2021 | } | |
0d48696f | 2022 | if (leader->attr.pinned) { |
53cfbf59 | 2023 | update_group_times(leader); |
cdd6c482 | 2024 | leader->state = PERF_EVENT_STATE_ERROR; |
53cfbf59 | 2025 | } |
d859e29f PM |
2026 | } |
2027 | ||
9ed6060d | 2028 | unlock: |
e625cce1 | 2029 | raw_spin_unlock(&ctx->lock); |
fe4b04fa PZ |
2030 | |
2031 | return 0; | |
d859e29f PM |
2032 | } |
2033 | ||
2034 | /* | |
cdd6c482 | 2035 | * Enable a event. |
c93f7669 | 2036 | * |
cdd6c482 IM |
2037 | * If event->ctx is a cloned context, callers must make sure that |
2038 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 2039 | * remains valid. This condition is satisfied when called through |
cdd6c482 IM |
2040 | * perf_event_for_each_child or perf_event_for_each as described |
2041 | * for perf_event_disable. | |
d859e29f | 2042 | */ |
44234adc | 2043 | void perf_event_enable(struct perf_event *event) |
d859e29f | 2044 | { |
cdd6c482 | 2045 | struct perf_event_context *ctx = event->ctx; |
d859e29f PM |
2046 | struct task_struct *task = ctx->task; |
2047 | ||
2048 | if (!task) { | |
2049 | /* | |
cdd6c482 | 2050 | * Enable the event on the cpu that it's on |
d859e29f | 2051 | */ |
fe4b04fa | 2052 | cpu_function_call(event->cpu, __perf_event_enable, event); |
d859e29f PM |
2053 | return; |
2054 | } | |
2055 | ||
e625cce1 | 2056 | raw_spin_lock_irq(&ctx->lock); |
cdd6c482 | 2057 | if (event->state >= PERF_EVENT_STATE_INACTIVE) |
d859e29f PM |
2058 | goto out; |
2059 | ||
2060 | /* | |
cdd6c482 IM |
2061 | * If the event is in error state, clear that first. |
2062 | * That way, if we see the event in error state below, we | |
d859e29f PM |
2063 | * know that it has gone back into error state, as distinct |
2064 | * from the task having been scheduled away before the | |
2065 | * cross-call arrived. | |
2066 | */ | |
cdd6c482 IM |
2067 | if (event->state == PERF_EVENT_STATE_ERROR) |
2068 | event->state = PERF_EVENT_STATE_OFF; | |
d859e29f | 2069 | |
9ed6060d | 2070 | retry: |
fe4b04fa | 2071 | if (!ctx->is_active) { |
1d9b482e | 2072 | __perf_event_mark_enabled(event); |
fe4b04fa PZ |
2073 | goto out; |
2074 | } | |
2075 | ||
e625cce1 | 2076 | raw_spin_unlock_irq(&ctx->lock); |
fe4b04fa PZ |
2077 | |
2078 | if (!task_function_call(task, __perf_event_enable, event)) | |
2079 | return; | |
d859e29f | 2080 | |
e625cce1 | 2081 | raw_spin_lock_irq(&ctx->lock); |
d859e29f PM |
2082 | |
2083 | /* | |
cdd6c482 | 2084 | * If the context is active and the event is still off, |
d859e29f PM |
2085 | * we need to retry the cross-call. |
2086 | */ | |
fe4b04fa PZ |
2087 | if (ctx->is_active && event->state == PERF_EVENT_STATE_OFF) { |
2088 | /* | |
2089 | * task could have been flipped by a concurrent | |
2090 | * perf_event_context_sched_out() | |
2091 | */ | |
2092 | task = ctx->task; | |
d859e29f | 2093 | goto retry; |
fe4b04fa | 2094 | } |
fa289bec | 2095 | |
9ed6060d | 2096 | out: |
e625cce1 | 2097 | raw_spin_unlock_irq(&ctx->lock); |
d859e29f | 2098 | } |
dcfce4a0 | 2099 | EXPORT_SYMBOL_GPL(perf_event_enable); |
d859e29f | 2100 | |
26ca5c11 | 2101 | int perf_event_refresh(struct perf_event *event, int refresh) |
79f14641 | 2102 | { |
2023b359 | 2103 | /* |
cdd6c482 | 2104 | * not supported on inherited events |
2023b359 | 2105 | */ |
2e939d1d | 2106 | if (event->attr.inherit || !is_sampling_event(event)) |
2023b359 PZ |
2107 | return -EINVAL; |
2108 | ||
cdd6c482 IM |
2109 | atomic_add(refresh, &event->event_limit); |
2110 | perf_event_enable(event); | |
2023b359 PZ |
2111 | |
2112 | return 0; | |
79f14641 | 2113 | } |
26ca5c11 | 2114 | EXPORT_SYMBOL_GPL(perf_event_refresh); |
79f14641 | 2115 | |
5b0311e1 FW |
2116 | static void ctx_sched_out(struct perf_event_context *ctx, |
2117 | struct perf_cpu_context *cpuctx, | |
2118 | enum event_type_t event_type) | |
235c7fc7 | 2119 | { |
cdd6c482 | 2120 | struct perf_event *event; |
db24d33e | 2121 | int is_active = ctx->is_active; |
235c7fc7 | 2122 | |
db24d33e | 2123 | ctx->is_active &= ~event_type; |
cdd6c482 | 2124 | if (likely(!ctx->nr_events)) |
facc4307 PZ |
2125 | return; |
2126 | ||
4af4998b | 2127 | update_context_time(ctx); |
e5d1367f | 2128 | update_cgrp_time_from_cpuctx(cpuctx); |
5b0311e1 | 2129 | if (!ctx->nr_active) |
facc4307 | 2130 | return; |
5b0311e1 | 2131 | |
075e0b00 | 2132 | perf_pmu_disable(ctx->pmu); |
db24d33e | 2133 | if ((is_active & EVENT_PINNED) && (event_type & EVENT_PINNED)) { |
889ff015 FW |
2134 | list_for_each_entry(event, &ctx->pinned_groups, group_entry) |
2135 | group_sched_out(event, cpuctx, ctx); | |
9ed6060d | 2136 | } |
889ff015 | 2137 | |
db24d33e | 2138 | if ((is_active & EVENT_FLEXIBLE) && (event_type & EVENT_FLEXIBLE)) { |
889ff015 | 2139 | list_for_each_entry(event, &ctx->flexible_groups, group_entry) |
8c9ed8e1 | 2140 | group_sched_out(event, cpuctx, ctx); |
9ed6060d | 2141 | } |
1b9a644f | 2142 | perf_pmu_enable(ctx->pmu); |
235c7fc7 IM |
2143 | } |
2144 | ||
564c2b21 PM |
2145 | /* |
2146 | * Test whether two contexts are equivalent, i.e. whether they | |
2147 | * have both been cloned from the same version of the same context | |
cdd6c482 IM |
2148 | * and they both have the same number of enabled events. |
2149 | * If the number of enabled events is the same, then the set | |
2150 | * of enabled events should be the same, because these are both | |
2151 | * inherited contexts, therefore we can't access individual events | |
564c2b21 | 2152 | * in them directly with an fd; we can only enable/disable all |
cdd6c482 | 2153 | * events via prctl, or enable/disable all events in a family |
564c2b21 PM |
2154 | * via ioctl, which will have the same effect on both contexts. |
2155 | */ | |
cdd6c482 IM |
2156 | static int context_equiv(struct perf_event_context *ctx1, |
2157 | struct perf_event_context *ctx2) | |
564c2b21 PM |
2158 | { |
2159 | return ctx1->parent_ctx && ctx1->parent_ctx == ctx2->parent_ctx | |
ad3a37de | 2160 | && ctx1->parent_gen == ctx2->parent_gen |
25346b93 | 2161 | && !ctx1->pin_count && !ctx2->pin_count; |
564c2b21 PM |
2162 | } |
2163 | ||
cdd6c482 IM |
2164 | static void __perf_event_sync_stat(struct perf_event *event, |
2165 | struct perf_event *next_event) | |
bfbd3381 PZ |
2166 | { |
2167 | u64 value; | |
2168 | ||
cdd6c482 | 2169 | if (!event->attr.inherit_stat) |
bfbd3381 PZ |
2170 | return; |
2171 | ||
2172 | /* | |
cdd6c482 | 2173 | * Update the event value, we cannot use perf_event_read() |
bfbd3381 PZ |
2174 | * because we're in the middle of a context switch and have IRQs |
2175 | * disabled, which upsets smp_call_function_single(), however | |
cdd6c482 | 2176 | * we know the event must be on the current CPU, therefore we |
bfbd3381 PZ |
2177 | * don't need to use it. |
2178 | */ | |
cdd6c482 IM |
2179 | switch (event->state) { |
2180 | case PERF_EVENT_STATE_ACTIVE: | |
3dbebf15 PZ |
2181 | event->pmu->read(event); |
2182 | /* fall-through */ | |
bfbd3381 | 2183 | |
cdd6c482 IM |
2184 | case PERF_EVENT_STATE_INACTIVE: |
2185 | update_event_times(event); | |
bfbd3381 PZ |
2186 | break; |
2187 | ||
2188 | default: | |
2189 | break; | |
2190 | } | |
2191 | ||
2192 | /* | |
cdd6c482 | 2193 | * In order to keep per-task stats reliable we need to flip the event |
bfbd3381 PZ |
2194 | * values when we flip the contexts. |
2195 | */ | |
e7850595 PZ |
2196 | value = local64_read(&next_event->count); |
2197 | value = local64_xchg(&event->count, value); | |
2198 | local64_set(&next_event->count, value); | |
bfbd3381 | 2199 | |
cdd6c482 IM |
2200 | swap(event->total_time_enabled, next_event->total_time_enabled); |
2201 | swap(event->total_time_running, next_event->total_time_running); | |
19d2e755 | 2202 | |
bfbd3381 | 2203 | /* |
19d2e755 | 2204 | * Since we swizzled the values, update the user visible data too. |
bfbd3381 | 2205 | */ |
cdd6c482 IM |
2206 | perf_event_update_userpage(event); |
2207 | perf_event_update_userpage(next_event); | |
bfbd3381 PZ |
2208 | } |
2209 | ||
2210 | #define list_next_entry(pos, member) \ | |
2211 | list_entry(pos->member.next, typeof(*pos), member) | |
2212 | ||
cdd6c482 IM |
2213 | static void perf_event_sync_stat(struct perf_event_context *ctx, |
2214 | struct perf_event_context *next_ctx) | |
bfbd3381 | 2215 | { |
cdd6c482 | 2216 | struct perf_event *event, *next_event; |
bfbd3381 PZ |
2217 | |
2218 | if (!ctx->nr_stat) | |
2219 | return; | |
2220 | ||
02ffdbc8 PZ |
2221 | update_context_time(ctx); |
2222 | ||
cdd6c482 IM |
2223 | event = list_first_entry(&ctx->event_list, |
2224 | struct perf_event, event_entry); | |
bfbd3381 | 2225 | |
cdd6c482 IM |
2226 | next_event = list_first_entry(&next_ctx->event_list, |
2227 | struct perf_event, event_entry); | |
bfbd3381 | 2228 | |
cdd6c482 IM |
2229 | while (&event->event_entry != &ctx->event_list && |
2230 | &next_event->event_entry != &next_ctx->event_list) { | |
bfbd3381 | 2231 | |
cdd6c482 | 2232 | __perf_event_sync_stat(event, next_event); |
bfbd3381 | 2233 | |
cdd6c482 IM |
2234 | event = list_next_entry(event, event_entry); |
2235 | next_event = list_next_entry(next_event, event_entry); | |
bfbd3381 PZ |
2236 | } |
2237 | } | |
2238 | ||
fe4b04fa PZ |
2239 | static void perf_event_context_sched_out(struct task_struct *task, int ctxn, |
2240 | struct task_struct *next) | |
0793a61d | 2241 | { |
8dc85d54 | 2242 | struct perf_event_context *ctx = task->perf_event_ctxp[ctxn]; |
cdd6c482 IM |
2243 | struct perf_event_context *next_ctx; |
2244 | struct perf_event_context *parent; | |
108b02cf | 2245 | struct perf_cpu_context *cpuctx; |
c93f7669 | 2246 | int do_switch = 1; |
0793a61d | 2247 | |
108b02cf PZ |
2248 | if (likely(!ctx)) |
2249 | return; | |
10989fb2 | 2250 | |
108b02cf PZ |
2251 | cpuctx = __get_cpu_context(ctx); |
2252 | if (!cpuctx->task_ctx) | |
0793a61d TG |
2253 | return; |
2254 | ||
c93f7669 PM |
2255 | rcu_read_lock(); |
2256 | parent = rcu_dereference(ctx->parent_ctx); | |
8dc85d54 | 2257 | next_ctx = next->perf_event_ctxp[ctxn]; |
c93f7669 PM |
2258 | if (parent && next_ctx && |
2259 | rcu_dereference(next_ctx->parent_ctx) == parent) { | |
2260 | /* | |
2261 | * Looks like the two contexts are clones, so we might be | |
2262 | * able to optimize the context switch. We lock both | |
2263 | * contexts and check that they are clones under the | |
2264 | * lock (including re-checking that neither has been | |
2265 | * uncloned in the meantime). It doesn't matter which | |
2266 | * order we take the locks because no other cpu could | |
2267 | * be trying to lock both of these tasks. | |
2268 | */ | |
e625cce1 TG |
2269 | raw_spin_lock(&ctx->lock); |
2270 | raw_spin_lock_nested(&next_ctx->lock, SINGLE_DEPTH_NESTING); | |
c93f7669 | 2271 | if (context_equiv(ctx, next_ctx)) { |
665c2142 PZ |
2272 | /* |
2273 | * XXX do we need a memory barrier of sorts | |
cdd6c482 | 2274 | * wrt to rcu_dereference() of perf_event_ctxp |
665c2142 | 2275 | */ |
8dc85d54 PZ |
2276 | task->perf_event_ctxp[ctxn] = next_ctx; |
2277 | next->perf_event_ctxp[ctxn] = ctx; | |
c93f7669 PM |
2278 | ctx->task = next; |
2279 | next_ctx->task = task; | |
2280 | do_switch = 0; | |
bfbd3381 | 2281 | |
cdd6c482 | 2282 | perf_event_sync_stat(ctx, next_ctx); |
c93f7669 | 2283 | } |
e625cce1 TG |
2284 | raw_spin_unlock(&next_ctx->lock); |
2285 | raw_spin_unlock(&ctx->lock); | |
564c2b21 | 2286 | } |
c93f7669 | 2287 | rcu_read_unlock(); |
564c2b21 | 2288 | |
c93f7669 | 2289 | if (do_switch) { |
facc4307 | 2290 | raw_spin_lock(&ctx->lock); |
5b0311e1 | 2291 | ctx_sched_out(ctx, cpuctx, EVENT_ALL); |
c93f7669 | 2292 | cpuctx->task_ctx = NULL; |
facc4307 | 2293 | raw_spin_unlock(&ctx->lock); |
c93f7669 | 2294 | } |
0793a61d TG |
2295 | } |
2296 | ||
8dc85d54 PZ |
2297 | #define for_each_task_context_nr(ctxn) \ |
2298 | for ((ctxn) = 0; (ctxn) < perf_nr_task_contexts; (ctxn)++) | |
2299 | ||
2300 | /* | |
2301 | * Called from scheduler to remove the events of the current task, | |
2302 | * with interrupts disabled. | |
2303 | * | |
2304 | * We stop each event and update the event value in event->count. | |
2305 | * | |
2306 | * This does not protect us against NMI, but disable() | |
2307 | * sets the disabled bit in the control field of event _before_ | |
2308 | * accessing the event control register. If a NMI hits, then it will | |
2309 | * not restart the event. | |
2310 | */ | |
ab0cce56 JO |
2311 | void __perf_event_task_sched_out(struct task_struct *task, |
2312 | struct task_struct *next) | |
8dc85d54 PZ |
2313 | { |
2314 | int ctxn; | |
2315 | ||
8dc85d54 PZ |
2316 | for_each_task_context_nr(ctxn) |
2317 | perf_event_context_sched_out(task, ctxn, next); | |
e5d1367f SE |
2318 | |
2319 | /* | |
2320 | * if cgroup events exist on this CPU, then we need | |
2321 | * to check if we have to switch out PMU state. | |
2322 | * cgroup event are system-wide mode only | |
2323 | */ | |
2324 | if (atomic_read(&__get_cpu_var(perf_cgroup_events))) | |
a8d757ef | 2325 | perf_cgroup_sched_out(task, next); |
8dc85d54 PZ |
2326 | } |
2327 | ||
04dc2dbb | 2328 | static void task_ctx_sched_out(struct perf_event_context *ctx) |
a08b159f | 2329 | { |
108b02cf | 2330 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
a08b159f | 2331 | |
a63eaf34 PM |
2332 | if (!cpuctx->task_ctx) |
2333 | return; | |
012b84da IM |
2334 | |
2335 | if (WARN_ON_ONCE(ctx != cpuctx->task_ctx)) | |
2336 | return; | |
2337 | ||
04dc2dbb | 2338 | ctx_sched_out(ctx, cpuctx, EVENT_ALL); |
a08b159f PM |
2339 | cpuctx->task_ctx = NULL; |
2340 | } | |
2341 | ||
5b0311e1 FW |
2342 | /* |
2343 | * Called with IRQs disabled | |
2344 | */ | |
2345 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, | |
2346 | enum event_type_t event_type) | |
2347 | { | |
2348 | ctx_sched_out(&cpuctx->ctx, cpuctx, event_type); | |
04289bb9 IM |
2349 | } |
2350 | ||
235c7fc7 | 2351 | static void |
5b0311e1 | 2352 | ctx_pinned_sched_in(struct perf_event_context *ctx, |
6e37738a | 2353 | struct perf_cpu_context *cpuctx) |
0793a61d | 2354 | { |
cdd6c482 | 2355 | struct perf_event *event; |
0793a61d | 2356 | |
889ff015 FW |
2357 | list_for_each_entry(event, &ctx->pinned_groups, group_entry) { |
2358 | if (event->state <= PERF_EVENT_STATE_OFF) | |
3b6f9e5c | 2359 | continue; |
5632ab12 | 2360 | if (!event_filter_match(event)) |
3b6f9e5c PM |
2361 | continue; |
2362 | ||
e5d1367f SE |
2363 | /* may need to reset tstamp_enabled */ |
2364 | if (is_cgroup_event(event)) | |
2365 | perf_cgroup_mark_enabled(event, ctx); | |
2366 | ||
8c9ed8e1 | 2367 | if (group_can_go_on(event, cpuctx, 1)) |
6e37738a | 2368 | group_sched_in(event, cpuctx, ctx); |
3b6f9e5c PM |
2369 | |
2370 | /* | |
2371 | * If this pinned group hasn't been scheduled, | |
2372 | * put it in error state. | |
2373 | */ | |
cdd6c482 IM |
2374 | if (event->state == PERF_EVENT_STATE_INACTIVE) { |
2375 | update_group_times(event); | |
2376 | event->state = PERF_EVENT_STATE_ERROR; | |
53cfbf59 | 2377 | } |
3b6f9e5c | 2378 | } |
5b0311e1 FW |
2379 | } |
2380 | ||
2381 | static void | |
2382 | ctx_flexible_sched_in(struct perf_event_context *ctx, | |
6e37738a | 2383 | struct perf_cpu_context *cpuctx) |
5b0311e1 FW |
2384 | { |
2385 | struct perf_event *event; | |
2386 | int can_add_hw = 1; | |
3b6f9e5c | 2387 | |
889ff015 FW |
2388 | list_for_each_entry(event, &ctx->flexible_groups, group_entry) { |
2389 | /* Ignore events in OFF or ERROR state */ | |
2390 | if (event->state <= PERF_EVENT_STATE_OFF) | |
3b6f9e5c | 2391 | continue; |
04289bb9 IM |
2392 | /* |
2393 | * Listen to the 'cpu' scheduling filter constraint | |
cdd6c482 | 2394 | * of events: |
04289bb9 | 2395 | */ |
5632ab12 | 2396 | if (!event_filter_match(event)) |
0793a61d TG |
2397 | continue; |
2398 | ||
e5d1367f SE |
2399 | /* may need to reset tstamp_enabled */ |
2400 | if (is_cgroup_event(event)) | |
2401 | perf_cgroup_mark_enabled(event, ctx); | |
2402 | ||
9ed6060d | 2403 | if (group_can_go_on(event, cpuctx, can_add_hw)) { |
6e37738a | 2404 | if (group_sched_in(event, cpuctx, ctx)) |
dd0e6ba2 | 2405 | can_add_hw = 0; |
9ed6060d | 2406 | } |
0793a61d | 2407 | } |
5b0311e1 FW |
2408 | } |
2409 | ||
2410 | static void | |
2411 | ctx_sched_in(struct perf_event_context *ctx, | |
2412 | struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
2413 | enum event_type_t event_type, |
2414 | struct task_struct *task) | |
5b0311e1 | 2415 | { |
e5d1367f | 2416 | u64 now; |
db24d33e | 2417 | int is_active = ctx->is_active; |
e5d1367f | 2418 | |
db24d33e | 2419 | ctx->is_active |= event_type; |
5b0311e1 | 2420 | if (likely(!ctx->nr_events)) |
facc4307 | 2421 | return; |
5b0311e1 | 2422 | |
e5d1367f SE |
2423 | now = perf_clock(); |
2424 | ctx->timestamp = now; | |
3f7cce3c | 2425 | perf_cgroup_set_timestamp(task, ctx); |
5b0311e1 FW |
2426 | /* |
2427 | * First go through the list and put on any pinned groups | |
2428 | * in order to give them the best chance of going on. | |
2429 | */ | |
db24d33e | 2430 | if (!(is_active & EVENT_PINNED) && (event_type & EVENT_PINNED)) |
6e37738a | 2431 | ctx_pinned_sched_in(ctx, cpuctx); |
5b0311e1 FW |
2432 | |
2433 | /* Then walk through the lower prio flexible groups */ | |
db24d33e | 2434 | if (!(is_active & EVENT_FLEXIBLE) && (event_type & EVENT_FLEXIBLE)) |
6e37738a | 2435 | ctx_flexible_sched_in(ctx, cpuctx); |
235c7fc7 IM |
2436 | } |
2437 | ||
329c0e01 | 2438 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, |
e5d1367f SE |
2439 | enum event_type_t event_type, |
2440 | struct task_struct *task) | |
329c0e01 FW |
2441 | { |
2442 | struct perf_event_context *ctx = &cpuctx->ctx; | |
2443 | ||
e5d1367f | 2444 | ctx_sched_in(ctx, cpuctx, event_type, task); |
329c0e01 FW |
2445 | } |
2446 | ||
e5d1367f SE |
2447 | static void perf_event_context_sched_in(struct perf_event_context *ctx, |
2448 | struct task_struct *task) | |
235c7fc7 | 2449 | { |
108b02cf | 2450 | struct perf_cpu_context *cpuctx; |
235c7fc7 | 2451 | |
108b02cf | 2452 | cpuctx = __get_cpu_context(ctx); |
329c0e01 FW |
2453 | if (cpuctx->task_ctx == ctx) |
2454 | return; | |
2455 | ||
facc4307 | 2456 | perf_ctx_lock(cpuctx, ctx); |
1b9a644f | 2457 | perf_pmu_disable(ctx->pmu); |
329c0e01 FW |
2458 | /* |
2459 | * We want to keep the following priority order: | |
2460 | * cpu pinned (that don't need to move), task pinned, | |
2461 | * cpu flexible, task flexible. | |
2462 | */ | |
2463 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
2464 | ||
1d5f003f GN |
2465 | if (ctx->nr_events) |
2466 | cpuctx->task_ctx = ctx; | |
9b33fa6b | 2467 | |
86b47c25 GN |
2468 | perf_event_sched_in(cpuctx, cpuctx->task_ctx, task); |
2469 | ||
facc4307 PZ |
2470 | perf_pmu_enable(ctx->pmu); |
2471 | perf_ctx_unlock(cpuctx, ctx); | |
2472 | ||
b5ab4cd5 PZ |
2473 | /* |
2474 | * Since these rotations are per-cpu, we need to ensure the | |
2475 | * cpu-context we got scheduled on is actually rotating. | |
2476 | */ | |
108b02cf | 2477 | perf_pmu_rotate_start(ctx->pmu); |
235c7fc7 IM |
2478 | } |
2479 | ||
d010b332 SE |
2480 | /* |
2481 | * When sampling the branck stack in system-wide, it may be necessary | |
2482 | * to flush the stack on context switch. This happens when the branch | |
2483 | * stack does not tag its entries with the pid of the current task. | |
2484 | * Otherwise it becomes impossible to associate a branch entry with a | |
2485 | * task. This ambiguity is more likely to appear when the branch stack | |
2486 | * supports priv level filtering and the user sets it to monitor only | |
2487 | * at the user level (which could be a useful measurement in system-wide | |
2488 | * mode). In that case, the risk is high of having a branch stack with | |
2489 | * branch from multiple tasks. Flushing may mean dropping the existing | |
2490 | * entries or stashing them somewhere in the PMU specific code layer. | |
2491 | * | |
2492 | * This function provides the context switch callback to the lower code | |
2493 | * layer. It is invoked ONLY when there is at least one system-wide context | |
2494 | * with at least one active event using taken branch sampling. | |
2495 | */ | |
2496 | static void perf_branch_stack_sched_in(struct task_struct *prev, | |
2497 | struct task_struct *task) | |
2498 | { | |
2499 | struct perf_cpu_context *cpuctx; | |
2500 | struct pmu *pmu; | |
2501 | unsigned long flags; | |
2502 | ||
2503 | /* no need to flush branch stack if not changing task */ | |
2504 | if (prev == task) | |
2505 | return; | |
2506 | ||
2507 | local_irq_save(flags); | |
2508 | ||
2509 | rcu_read_lock(); | |
2510 | ||
2511 | list_for_each_entry_rcu(pmu, &pmus, entry) { | |
2512 | cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); | |
2513 | ||
2514 | /* | |
2515 | * check if the context has at least one | |
2516 | * event using PERF_SAMPLE_BRANCH_STACK | |
2517 | */ | |
2518 | if (cpuctx->ctx.nr_branch_stack > 0 | |
2519 | && pmu->flush_branch_stack) { | |
2520 | ||
2521 | pmu = cpuctx->ctx.pmu; | |
2522 | ||
2523 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); | |
2524 | ||
2525 | perf_pmu_disable(pmu); | |
2526 | ||
2527 | pmu->flush_branch_stack(); | |
2528 | ||
2529 | perf_pmu_enable(pmu); | |
2530 | ||
2531 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
2532 | } | |
2533 | } | |
2534 | ||
2535 | rcu_read_unlock(); | |
2536 | ||
2537 | local_irq_restore(flags); | |
2538 | } | |
2539 | ||
8dc85d54 PZ |
2540 | /* |
2541 | * Called from scheduler to add the events of the current task | |
2542 | * with interrupts disabled. | |
2543 | * | |
2544 | * We restore the event value and then enable it. | |
2545 | * | |
2546 | * This does not protect us against NMI, but enable() | |
2547 | * sets the enabled bit in the control field of event _before_ | |
2548 | * accessing the event control register. If a NMI hits, then it will | |
2549 | * keep the event running. | |
2550 | */ | |
ab0cce56 JO |
2551 | void __perf_event_task_sched_in(struct task_struct *prev, |
2552 | struct task_struct *task) | |
8dc85d54 PZ |
2553 | { |
2554 | struct perf_event_context *ctx; | |
2555 | int ctxn; | |
2556 | ||
2557 | for_each_task_context_nr(ctxn) { | |
2558 | ctx = task->perf_event_ctxp[ctxn]; | |
2559 | if (likely(!ctx)) | |
2560 | continue; | |
2561 | ||
e5d1367f | 2562 | perf_event_context_sched_in(ctx, task); |
8dc85d54 | 2563 | } |
e5d1367f SE |
2564 | /* |
2565 | * if cgroup events exist on this CPU, then we need | |
2566 | * to check if we have to switch in PMU state. | |
2567 | * cgroup event are system-wide mode only | |
2568 | */ | |
2569 | if (atomic_read(&__get_cpu_var(perf_cgroup_events))) | |
a8d757ef | 2570 | perf_cgroup_sched_in(prev, task); |
d010b332 SE |
2571 | |
2572 | /* check for system-wide branch_stack events */ | |
2573 | if (atomic_read(&__get_cpu_var(perf_branch_stack_events))) | |
2574 | perf_branch_stack_sched_in(prev, task); | |
235c7fc7 IM |
2575 | } |
2576 | ||
abd50713 PZ |
2577 | static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count) |
2578 | { | |
2579 | u64 frequency = event->attr.sample_freq; | |
2580 | u64 sec = NSEC_PER_SEC; | |
2581 | u64 divisor, dividend; | |
2582 | ||
2583 | int count_fls, nsec_fls, frequency_fls, sec_fls; | |
2584 | ||
2585 | count_fls = fls64(count); | |
2586 | nsec_fls = fls64(nsec); | |
2587 | frequency_fls = fls64(frequency); | |
2588 | sec_fls = 30; | |
2589 | ||
2590 | /* | |
2591 | * We got @count in @nsec, with a target of sample_freq HZ | |
2592 | * the target period becomes: | |
2593 | * | |
2594 | * @count * 10^9 | |
2595 | * period = ------------------- | |
2596 | * @nsec * sample_freq | |
2597 | * | |
2598 | */ | |
2599 | ||
2600 | /* | |
2601 | * Reduce accuracy by one bit such that @a and @b converge | |
2602 | * to a similar magnitude. | |
2603 | */ | |
fe4b04fa | 2604 | #define REDUCE_FLS(a, b) \ |
abd50713 PZ |
2605 | do { \ |
2606 | if (a##_fls > b##_fls) { \ | |
2607 | a >>= 1; \ | |
2608 | a##_fls--; \ | |
2609 | } else { \ | |
2610 | b >>= 1; \ | |
2611 | b##_fls--; \ | |
2612 | } \ | |
2613 | } while (0) | |
2614 | ||
2615 | /* | |
2616 | * Reduce accuracy until either term fits in a u64, then proceed with | |
2617 | * the other, so that finally we can do a u64/u64 division. | |
2618 | */ | |
2619 | while (count_fls + sec_fls > 64 && nsec_fls + frequency_fls > 64) { | |
2620 | REDUCE_FLS(nsec, frequency); | |
2621 | REDUCE_FLS(sec, count); | |
2622 | } | |
2623 | ||
2624 | if (count_fls + sec_fls > 64) { | |
2625 | divisor = nsec * frequency; | |
2626 | ||
2627 | while (count_fls + sec_fls > 64) { | |
2628 | REDUCE_FLS(count, sec); | |
2629 | divisor >>= 1; | |
2630 | } | |
2631 | ||
2632 | dividend = count * sec; | |
2633 | } else { | |
2634 | dividend = count * sec; | |
2635 | ||
2636 | while (nsec_fls + frequency_fls > 64) { | |
2637 | REDUCE_FLS(nsec, frequency); | |
2638 | dividend >>= 1; | |
2639 | } | |
2640 | ||
2641 | divisor = nsec * frequency; | |
2642 | } | |
2643 | ||
f6ab91ad PZ |
2644 | if (!divisor) |
2645 | return dividend; | |
2646 | ||
abd50713 PZ |
2647 | return div64_u64(dividend, divisor); |
2648 | } | |
2649 | ||
e050e3f0 SE |
2650 | static DEFINE_PER_CPU(int, perf_throttled_count); |
2651 | static DEFINE_PER_CPU(u64, perf_throttled_seq); | |
2652 | ||
f39d47ff | 2653 | static void perf_adjust_period(struct perf_event *event, u64 nsec, u64 count, bool disable) |
bd2b5b12 | 2654 | { |
cdd6c482 | 2655 | struct hw_perf_event *hwc = &event->hw; |
f6ab91ad | 2656 | s64 period, sample_period; |
bd2b5b12 PZ |
2657 | s64 delta; |
2658 | ||
abd50713 | 2659 | period = perf_calculate_period(event, nsec, count); |
bd2b5b12 PZ |
2660 | |
2661 | delta = (s64)(period - hwc->sample_period); | |
2662 | delta = (delta + 7) / 8; /* low pass filter */ | |
2663 | ||
2664 | sample_period = hwc->sample_period + delta; | |
2665 | ||
2666 | if (!sample_period) | |
2667 | sample_period = 1; | |
2668 | ||
bd2b5b12 | 2669 | hwc->sample_period = sample_period; |
abd50713 | 2670 | |
e7850595 | 2671 | if (local64_read(&hwc->period_left) > 8*sample_period) { |
f39d47ff SE |
2672 | if (disable) |
2673 | event->pmu->stop(event, PERF_EF_UPDATE); | |
2674 | ||
e7850595 | 2675 | local64_set(&hwc->period_left, 0); |
f39d47ff SE |
2676 | |
2677 | if (disable) | |
2678 | event->pmu->start(event, PERF_EF_RELOAD); | |
abd50713 | 2679 | } |
bd2b5b12 PZ |
2680 | } |
2681 | ||
e050e3f0 SE |
2682 | /* |
2683 | * combine freq adjustment with unthrottling to avoid two passes over the | |
2684 | * events. At the same time, make sure, having freq events does not change | |
2685 | * the rate of unthrottling as that would introduce bias. | |
2686 | */ | |
2687 | static void perf_adjust_freq_unthr_context(struct perf_event_context *ctx, | |
2688 | int needs_unthr) | |
60db5e09 | 2689 | { |
cdd6c482 IM |
2690 | struct perf_event *event; |
2691 | struct hw_perf_event *hwc; | |
e050e3f0 | 2692 | u64 now, period = TICK_NSEC; |
abd50713 | 2693 | s64 delta; |
60db5e09 | 2694 | |
e050e3f0 SE |
2695 | /* |
2696 | * only need to iterate over all events iff: | |
2697 | * - context have events in frequency mode (needs freq adjust) | |
2698 | * - there are events to unthrottle on this cpu | |
2699 | */ | |
2700 | if (!(ctx->nr_freq || needs_unthr)) | |
0f5a2601 PZ |
2701 | return; |
2702 | ||
e050e3f0 | 2703 | raw_spin_lock(&ctx->lock); |
f39d47ff | 2704 | perf_pmu_disable(ctx->pmu); |
e050e3f0 | 2705 | |
03541f8b | 2706 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { |
cdd6c482 | 2707 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
60db5e09 PZ |
2708 | continue; |
2709 | ||
5632ab12 | 2710 | if (!event_filter_match(event)) |
5d27c23d PZ |
2711 | continue; |
2712 | ||
cdd6c482 | 2713 | hwc = &event->hw; |
6a24ed6c | 2714 | |
e050e3f0 SE |
2715 | if (needs_unthr && hwc->interrupts == MAX_INTERRUPTS) { |
2716 | hwc->interrupts = 0; | |
cdd6c482 | 2717 | perf_log_throttle(event, 1); |
a4eaf7f1 | 2718 | event->pmu->start(event, 0); |
a78ac325 PZ |
2719 | } |
2720 | ||
cdd6c482 | 2721 | if (!event->attr.freq || !event->attr.sample_freq) |
60db5e09 PZ |
2722 | continue; |
2723 | ||
e050e3f0 SE |
2724 | /* |
2725 | * stop the event and update event->count | |
2726 | */ | |
2727 | event->pmu->stop(event, PERF_EF_UPDATE); | |
2728 | ||
e7850595 | 2729 | now = local64_read(&event->count); |
abd50713 PZ |
2730 | delta = now - hwc->freq_count_stamp; |
2731 | hwc->freq_count_stamp = now; | |
60db5e09 | 2732 | |
e050e3f0 SE |
2733 | /* |
2734 | * restart the event | |
2735 | * reload only if value has changed | |
f39d47ff SE |
2736 | * we have stopped the event so tell that |
2737 | * to perf_adjust_period() to avoid stopping it | |
2738 | * twice. | |
e050e3f0 | 2739 | */ |
abd50713 | 2740 | if (delta > 0) |
f39d47ff | 2741 | perf_adjust_period(event, period, delta, false); |
e050e3f0 SE |
2742 | |
2743 | event->pmu->start(event, delta > 0 ? PERF_EF_RELOAD : 0); | |
60db5e09 | 2744 | } |
e050e3f0 | 2745 | |
f39d47ff | 2746 | perf_pmu_enable(ctx->pmu); |
e050e3f0 | 2747 | raw_spin_unlock(&ctx->lock); |
60db5e09 PZ |
2748 | } |
2749 | ||
235c7fc7 | 2750 | /* |
cdd6c482 | 2751 | * Round-robin a context's events: |
235c7fc7 | 2752 | */ |
cdd6c482 | 2753 | static void rotate_ctx(struct perf_event_context *ctx) |
0793a61d | 2754 | { |
dddd3379 TG |
2755 | /* |
2756 | * Rotate the first entry last of non-pinned groups. Rotation might be | |
2757 | * disabled by the inheritance code. | |
2758 | */ | |
2759 | if (!ctx->rotate_disable) | |
2760 | list_rotate_left(&ctx->flexible_groups); | |
235c7fc7 IM |
2761 | } |
2762 | ||
b5ab4cd5 | 2763 | /* |
e9d2b064 PZ |
2764 | * perf_pmu_rotate_start() and perf_rotate_context() are fully serialized |
2765 | * because they're strictly cpu affine and rotate_start is called with IRQs | |
2766 | * disabled, while rotate_context is called from IRQ context. | |
b5ab4cd5 | 2767 | */ |
9e630205 | 2768 | static int perf_rotate_context(struct perf_cpu_context *cpuctx) |
235c7fc7 | 2769 | { |
8dc85d54 | 2770 | struct perf_event_context *ctx = NULL; |
e050e3f0 | 2771 | int rotate = 0, remove = 1; |
7fc23a53 | 2772 | |
b5ab4cd5 | 2773 | if (cpuctx->ctx.nr_events) { |
e9d2b064 | 2774 | remove = 0; |
b5ab4cd5 PZ |
2775 | if (cpuctx->ctx.nr_events != cpuctx->ctx.nr_active) |
2776 | rotate = 1; | |
2777 | } | |
235c7fc7 | 2778 | |
8dc85d54 | 2779 | ctx = cpuctx->task_ctx; |
b5ab4cd5 | 2780 | if (ctx && ctx->nr_events) { |
e9d2b064 | 2781 | remove = 0; |
b5ab4cd5 PZ |
2782 | if (ctx->nr_events != ctx->nr_active) |
2783 | rotate = 1; | |
2784 | } | |
9717e6cd | 2785 | |
e050e3f0 | 2786 | if (!rotate) |
0f5a2601 PZ |
2787 | goto done; |
2788 | ||
facc4307 | 2789 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
1b9a644f | 2790 | perf_pmu_disable(cpuctx->ctx.pmu); |
60db5e09 | 2791 | |
e050e3f0 SE |
2792 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); |
2793 | if (ctx) | |
2794 | ctx_sched_out(ctx, cpuctx, EVENT_FLEXIBLE); | |
0793a61d | 2795 | |
e050e3f0 SE |
2796 | rotate_ctx(&cpuctx->ctx); |
2797 | if (ctx) | |
2798 | rotate_ctx(ctx); | |
235c7fc7 | 2799 | |
e050e3f0 | 2800 | perf_event_sched_in(cpuctx, ctx, current); |
235c7fc7 | 2801 | |
0f5a2601 PZ |
2802 | perf_pmu_enable(cpuctx->ctx.pmu); |
2803 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
b5ab4cd5 | 2804 | done: |
e9d2b064 PZ |
2805 | if (remove) |
2806 | list_del_init(&cpuctx->rotation_list); | |
9e630205 SE |
2807 | |
2808 | return rotate; | |
e9d2b064 PZ |
2809 | } |
2810 | ||
026249ef FW |
2811 | #ifdef CONFIG_NO_HZ_FULL |
2812 | bool perf_event_can_stop_tick(void) | |
2813 | { | |
2814 | if (list_empty(&__get_cpu_var(rotation_list))) | |
2815 | return true; | |
2816 | else | |
2817 | return false; | |
2818 | } | |
2819 | #endif | |
2820 | ||
e9d2b064 PZ |
2821 | void perf_event_task_tick(void) |
2822 | { | |
2823 | struct list_head *head = &__get_cpu_var(rotation_list); | |
2824 | struct perf_cpu_context *cpuctx, *tmp; | |
e050e3f0 SE |
2825 | struct perf_event_context *ctx; |
2826 | int throttled; | |
b5ab4cd5 | 2827 | |
e9d2b064 PZ |
2828 | WARN_ON(!irqs_disabled()); |
2829 | ||
e050e3f0 SE |
2830 | __this_cpu_inc(perf_throttled_seq); |
2831 | throttled = __this_cpu_xchg(perf_throttled_count, 0); | |
2832 | ||
e9d2b064 | 2833 | list_for_each_entry_safe(cpuctx, tmp, head, rotation_list) { |
e050e3f0 SE |
2834 | ctx = &cpuctx->ctx; |
2835 | perf_adjust_freq_unthr_context(ctx, throttled); | |
2836 | ||
2837 | ctx = cpuctx->task_ctx; | |
2838 | if (ctx) | |
2839 | perf_adjust_freq_unthr_context(ctx, throttled); | |
e9d2b064 | 2840 | } |
0793a61d TG |
2841 | } |
2842 | ||
889ff015 FW |
2843 | static int event_enable_on_exec(struct perf_event *event, |
2844 | struct perf_event_context *ctx) | |
2845 | { | |
2846 | if (!event->attr.enable_on_exec) | |
2847 | return 0; | |
2848 | ||
2849 | event->attr.enable_on_exec = 0; | |
2850 | if (event->state >= PERF_EVENT_STATE_INACTIVE) | |
2851 | return 0; | |
2852 | ||
1d9b482e | 2853 | __perf_event_mark_enabled(event); |
889ff015 FW |
2854 | |
2855 | return 1; | |
2856 | } | |
2857 | ||
57e7986e | 2858 | /* |
cdd6c482 | 2859 | * Enable all of a task's events that have been marked enable-on-exec. |
57e7986e PM |
2860 | * This expects task == current. |
2861 | */ | |
8dc85d54 | 2862 | static void perf_event_enable_on_exec(struct perf_event_context *ctx) |
57e7986e | 2863 | { |
cdd6c482 | 2864 | struct perf_event *event; |
57e7986e PM |
2865 | unsigned long flags; |
2866 | int enabled = 0; | |
889ff015 | 2867 | int ret; |
57e7986e PM |
2868 | |
2869 | local_irq_save(flags); | |
cdd6c482 | 2870 | if (!ctx || !ctx->nr_events) |
57e7986e PM |
2871 | goto out; |
2872 | ||
e566b76e SE |
2873 | /* |
2874 | * We must ctxsw out cgroup events to avoid conflict | |
2875 | * when invoking perf_task_event_sched_in() later on | |
2876 | * in this function. Otherwise we end up trying to | |
2877 | * ctxswin cgroup events which are already scheduled | |
2878 | * in. | |
2879 | */ | |
a8d757ef | 2880 | perf_cgroup_sched_out(current, NULL); |
57e7986e | 2881 | |
e625cce1 | 2882 | raw_spin_lock(&ctx->lock); |
04dc2dbb | 2883 | task_ctx_sched_out(ctx); |
57e7986e | 2884 | |
b79387ef | 2885 | list_for_each_entry(event, &ctx->event_list, event_entry) { |
889ff015 FW |
2886 | ret = event_enable_on_exec(event, ctx); |
2887 | if (ret) | |
2888 | enabled = 1; | |
57e7986e PM |
2889 | } |
2890 | ||
2891 | /* | |
cdd6c482 | 2892 | * Unclone this context if we enabled any event. |
57e7986e | 2893 | */ |
71a851b4 PZ |
2894 | if (enabled) |
2895 | unclone_ctx(ctx); | |
57e7986e | 2896 | |
e625cce1 | 2897 | raw_spin_unlock(&ctx->lock); |
57e7986e | 2898 | |
e566b76e SE |
2899 | /* |
2900 | * Also calls ctxswin for cgroup events, if any: | |
2901 | */ | |
e5d1367f | 2902 | perf_event_context_sched_in(ctx, ctx->task); |
9ed6060d | 2903 | out: |
57e7986e PM |
2904 | local_irq_restore(flags); |
2905 | } | |
2906 | ||
0793a61d | 2907 | /* |
cdd6c482 | 2908 | * Cross CPU call to read the hardware event |
0793a61d | 2909 | */ |
cdd6c482 | 2910 | static void __perf_event_read(void *info) |
0793a61d | 2911 | { |
cdd6c482 IM |
2912 | struct perf_event *event = info; |
2913 | struct perf_event_context *ctx = event->ctx; | |
108b02cf | 2914 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
621a01ea | 2915 | |
e1ac3614 PM |
2916 | /* |
2917 | * If this is a task context, we need to check whether it is | |
2918 | * the current task context of this cpu. If not it has been | |
2919 | * scheduled out before the smp call arrived. In that case | |
cdd6c482 IM |
2920 | * event->count would have been updated to a recent sample |
2921 | * when the event was scheduled out. | |
e1ac3614 PM |
2922 | */ |
2923 | if (ctx->task && cpuctx->task_ctx != ctx) | |
2924 | return; | |
2925 | ||
e625cce1 | 2926 | raw_spin_lock(&ctx->lock); |
e5d1367f | 2927 | if (ctx->is_active) { |
542e72fc | 2928 | update_context_time(ctx); |
e5d1367f SE |
2929 | update_cgrp_time_from_event(event); |
2930 | } | |
cdd6c482 | 2931 | update_event_times(event); |
542e72fc PZ |
2932 | if (event->state == PERF_EVENT_STATE_ACTIVE) |
2933 | event->pmu->read(event); | |
e625cce1 | 2934 | raw_spin_unlock(&ctx->lock); |
0793a61d TG |
2935 | } |
2936 | ||
b5e58793 PZ |
2937 | static inline u64 perf_event_count(struct perf_event *event) |
2938 | { | |
e7850595 | 2939 | return local64_read(&event->count) + atomic64_read(&event->child_count); |
b5e58793 PZ |
2940 | } |
2941 | ||
cdd6c482 | 2942 | static u64 perf_event_read(struct perf_event *event) |
0793a61d TG |
2943 | { |
2944 | /* | |
cdd6c482 IM |
2945 | * If event is enabled and currently active on a CPU, update the |
2946 | * value in the event structure: | |
0793a61d | 2947 | */ |
cdd6c482 IM |
2948 | if (event->state == PERF_EVENT_STATE_ACTIVE) { |
2949 | smp_call_function_single(event->oncpu, | |
2950 | __perf_event_read, event, 1); | |
2951 | } else if (event->state == PERF_EVENT_STATE_INACTIVE) { | |
2b8988c9 PZ |
2952 | struct perf_event_context *ctx = event->ctx; |
2953 | unsigned long flags; | |
2954 | ||
e625cce1 | 2955 | raw_spin_lock_irqsave(&ctx->lock, flags); |
c530ccd9 SE |
2956 | /* |
2957 | * may read while context is not active | |
2958 | * (e.g., thread is blocked), in that case | |
2959 | * we cannot update context time | |
2960 | */ | |
e5d1367f | 2961 | if (ctx->is_active) { |
c530ccd9 | 2962 | update_context_time(ctx); |
e5d1367f SE |
2963 | update_cgrp_time_from_event(event); |
2964 | } | |
cdd6c482 | 2965 | update_event_times(event); |
e625cce1 | 2966 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
0793a61d TG |
2967 | } |
2968 | ||
b5e58793 | 2969 | return perf_event_count(event); |
0793a61d TG |
2970 | } |
2971 | ||
a63eaf34 | 2972 | /* |
cdd6c482 | 2973 | * Initialize the perf_event context in a task_struct: |
a63eaf34 | 2974 | */ |
eb184479 | 2975 | static void __perf_event_init_context(struct perf_event_context *ctx) |
a63eaf34 | 2976 | { |
e625cce1 | 2977 | raw_spin_lock_init(&ctx->lock); |
a63eaf34 | 2978 | mutex_init(&ctx->mutex); |
889ff015 FW |
2979 | INIT_LIST_HEAD(&ctx->pinned_groups); |
2980 | INIT_LIST_HEAD(&ctx->flexible_groups); | |
a63eaf34 PM |
2981 | INIT_LIST_HEAD(&ctx->event_list); |
2982 | atomic_set(&ctx->refcount, 1); | |
eb184479 PZ |
2983 | } |
2984 | ||
2985 | static struct perf_event_context * | |
2986 | alloc_perf_context(struct pmu *pmu, struct task_struct *task) | |
2987 | { | |
2988 | struct perf_event_context *ctx; | |
2989 | ||
2990 | ctx = kzalloc(sizeof(struct perf_event_context), GFP_KERNEL); | |
2991 | if (!ctx) | |
2992 | return NULL; | |
2993 | ||
2994 | __perf_event_init_context(ctx); | |
2995 | if (task) { | |
2996 | ctx->task = task; | |
2997 | get_task_struct(task); | |
0793a61d | 2998 | } |
eb184479 PZ |
2999 | ctx->pmu = pmu; |
3000 | ||
3001 | return ctx; | |
a63eaf34 PM |
3002 | } |
3003 | ||
2ebd4ffb MH |
3004 | static struct task_struct * |
3005 | find_lively_task_by_vpid(pid_t vpid) | |
3006 | { | |
3007 | struct task_struct *task; | |
3008 | int err; | |
0793a61d TG |
3009 | |
3010 | rcu_read_lock(); | |
2ebd4ffb | 3011 | if (!vpid) |
0793a61d TG |
3012 | task = current; |
3013 | else | |
2ebd4ffb | 3014 | task = find_task_by_vpid(vpid); |
0793a61d TG |
3015 | if (task) |
3016 | get_task_struct(task); | |
3017 | rcu_read_unlock(); | |
3018 | ||
3019 | if (!task) | |
3020 | return ERR_PTR(-ESRCH); | |
3021 | ||
0793a61d | 3022 | /* Reuse ptrace permission checks for now. */ |
c93f7669 PM |
3023 | err = -EACCES; |
3024 | if (!ptrace_may_access(task, PTRACE_MODE_READ)) | |
3025 | goto errout; | |
3026 | ||
2ebd4ffb MH |
3027 | return task; |
3028 | errout: | |
3029 | put_task_struct(task); | |
3030 | return ERR_PTR(err); | |
3031 | ||
3032 | } | |
3033 | ||
fe4b04fa PZ |
3034 | /* |
3035 | * Returns a matching context with refcount and pincount. | |
3036 | */ | |
108b02cf | 3037 | static struct perf_event_context * |
38a81da2 | 3038 | find_get_context(struct pmu *pmu, struct task_struct *task, int cpu) |
0793a61d | 3039 | { |
cdd6c482 | 3040 | struct perf_event_context *ctx; |
22a4f650 | 3041 | struct perf_cpu_context *cpuctx; |
25346b93 | 3042 | unsigned long flags; |
8dc85d54 | 3043 | int ctxn, err; |
0793a61d | 3044 | |
22a4ec72 | 3045 | if (!task) { |
cdd6c482 | 3046 | /* Must be root to operate on a CPU event: */ |
0764771d | 3047 | if (perf_paranoid_cpu() && !capable(CAP_SYS_ADMIN)) |
0793a61d TG |
3048 | return ERR_PTR(-EACCES); |
3049 | ||
0793a61d | 3050 | /* |
cdd6c482 | 3051 | * We could be clever and allow to attach a event to an |
0793a61d TG |
3052 | * offline CPU and activate it when the CPU comes up, but |
3053 | * that's for later. | |
3054 | */ | |
f6325e30 | 3055 | if (!cpu_online(cpu)) |
0793a61d TG |
3056 | return ERR_PTR(-ENODEV); |
3057 | ||
108b02cf | 3058 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); |
0793a61d | 3059 | ctx = &cpuctx->ctx; |
c93f7669 | 3060 | get_ctx(ctx); |
fe4b04fa | 3061 | ++ctx->pin_count; |
0793a61d | 3062 | |
0793a61d TG |
3063 | return ctx; |
3064 | } | |
3065 | ||
8dc85d54 PZ |
3066 | err = -EINVAL; |
3067 | ctxn = pmu->task_ctx_nr; | |
3068 | if (ctxn < 0) | |
3069 | goto errout; | |
3070 | ||
9ed6060d | 3071 | retry: |
8dc85d54 | 3072 | ctx = perf_lock_task_context(task, ctxn, &flags); |
c93f7669 | 3073 | if (ctx) { |
71a851b4 | 3074 | unclone_ctx(ctx); |
fe4b04fa | 3075 | ++ctx->pin_count; |
e625cce1 | 3076 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
9137fb28 | 3077 | } else { |
eb184479 | 3078 | ctx = alloc_perf_context(pmu, task); |
c93f7669 PM |
3079 | err = -ENOMEM; |
3080 | if (!ctx) | |
3081 | goto errout; | |
eb184479 | 3082 | |
dbe08d82 ON |
3083 | err = 0; |
3084 | mutex_lock(&task->perf_event_mutex); | |
3085 | /* | |
3086 | * If it has already passed perf_event_exit_task(). | |
3087 | * we must see PF_EXITING, it takes this mutex too. | |
3088 | */ | |
3089 | if (task->flags & PF_EXITING) | |
3090 | err = -ESRCH; | |
3091 | else if (task->perf_event_ctxp[ctxn]) | |
3092 | err = -EAGAIN; | |
fe4b04fa | 3093 | else { |
9137fb28 | 3094 | get_ctx(ctx); |
fe4b04fa | 3095 | ++ctx->pin_count; |
dbe08d82 | 3096 | rcu_assign_pointer(task->perf_event_ctxp[ctxn], ctx); |
fe4b04fa | 3097 | } |
dbe08d82 ON |
3098 | mutex_unlock(&task->perf_event_mutex); |
3099 | ||
3100 | if (unlikely(err)) { | |
9137fb28 | 3101 | put_ctx(ctx); |
dbe08d82 ON |
3102 | |
3103 | if (err == -EAGAIN) | |
3104 | goto retry; | |
3105 | goto errout; | |
a63eaf34 PM |
3106 | } |
3107 | } | |
3108 | ||
0793a61d | 3109 | return ctx; |
c93f7669 | 3110 | |
9ed6060d | 3111 | errout: |
c93f7669 | 3112 | return ERR_PTR(err); |
0793a61d TG |
3113 | } |
3114 | ||
6fb2915d LZ |
3115 | static void perf_event_free_filter(struct perf_event *event); |
3116 | ||
cdd6c482 | 3117 | static void free_event_rcu(struct rcu_head *head) |
592903cd | 3118 | { |
cdd6c482 | 3119 | struct perf_event *event; |
592903cd | 3120 | |
cdd6c482 IM |
3121 | event = container_of(head, struct perf_event, rcu_head); |
3122 | if (event->ns) | |
3123 | put_pid_ns(event->ns); | |
6fb2915d | 3124 | perf_event_free_filter(event); |
cdd6c482 | 3125 | kfree(event); |
592903cd PZ |
3126 | } |
3127 | ||
76369139 | 3128 | static void ring_buffer_put(struct ring_buffer *rb); |
9bb5d40c | 3129 | static void ring_buffer_detach(struct perf_event *event, struct ring_buffer *rb); |
925d519a | 3130 | |
cdd6c482 | 3131 | static void free_event(struct perf_event *event) |
f1600952 | 3132 | { |
e360adbe | 3133 | irq_work_sync(&event->pending); |
925d519a | 3134 | |
cdd6c482 | 3135 | if (!event->parent) { |
82cd6def | 3136 | if (event->attach_state & PERF_ATTACH_TASK) |
c5905afb | 3137 | static_key_slow_dec_deferred(&perf_sched_events); |
3af9e859 | 3138 | if (event->attr.mmap || event->attr.mmap_data) |
cdd6c482 IM |
3139 | atomic_dec(&nr_mmap_events); |
3140 | if (event->attr.comm) | |
3141 | atomic_dec(&nr_comm_events); | |
3142 | if (event->attr.task) | |
3143 | atomic_dec(&nr_task_events); | |
927c7a9e FW |
3144 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) |
3145 | put_callchain_buffers(); | |
08309379 PZ |
3146 | if (is_cgroup_event(event)) { |
3147 | atomic_dec(&per_cpu(perf_cgroup_events, event->cpu)); | |
c5905afb | 3148 | static_key_slow_dec_deferred(&perf_sched_events); |
08309379 | 3149 | } |
d010b332 SE |
3150 | |
3151 | if (has_branch_stack(event)) { | |
3152 | static_key_slow_dec_deferred(&perf_sched_events); | |
3153 | /* is system-wide event */ | |
9bb5d40c | 3154 | if (!(event->attach_state & PERF_ATTACH_TASK)) { |
d010b332 SE |
3155 | atomic_dec(&per_cpu(perf_branch_stack_events, |
3156 | event->cpu)); | |
9bb5d40c | 3157 | } |
d010b332 | 3158 | } |
f344011c | 3159 | } |
9ee318a7 | 3160 | |
76369139 | 3161 | if (event->rb) { |
9bb5d40c PZ |
3162 | struct ring_buffer *rb; |
3163 | ||
3164 | /* | |
3165 | * Can happen when we close an event with re-directed output. | |
3166 | * | |
3167 | * Since we have a 0 refcount, perf_mmap_close() will skip | |
3168 | * over us; possibly making our ring_buffer_put() the last. | |
3169 | */ | |
3170 | mutex_lock(&event->mmap_mutex); | |
3171 | rb = event->rb; | |
3172 | if (rb) { | |
3173 | rcu_assign_pointer(event->rb, NULL); | |
3174 | ring_buffer_detach(event, rb); | |
3175 | ring_buffer_put(rb); /* could be last */ | |
3176 | } | |
3177 | mutex_unlock(&event->mmap_mutex); | |
a4be7c27 PZ |
3178 | } |
3179 | ||
e5d1367f SE |
3180 | if (is_cgroup_event(event)) |
3181 | perf_detach_cgroup(event); | |
3182 | ||
cdd6c482 IM |
3183 | if (event->destroy) |
3184 | event->destroy(event); | |
e077df4f | 3185 | |
0c67b408 PZ |
3186 | if (event->ctx) |
3187 | put_ctx(event->ctx); | |
3188 | ||
cdd6c482 | 3189 | call_rcu(&event->rcu_head, free_event_rcu); |
f1600952 PZ |
3190 | } |
3191 | ||
a66a3052 | 3192 | int perf_event_release_kernel(struct perf_event *event) |
0793a61d | 3193 | { |
cdd6c482 | 3194 | struct perf_event_context *ctx = event->ctx; |
0793a61d | 3195 | |
ad3a37de | 3196 | WARN_ON_ONCE(ctx->parent_ctx); |
a0507c84 PZ |
3197 | /* |
3198 | * There are two ways this annotation is useful: | |
3199 | * | |
3200 | * 1) there is a lock recursion from perf_event_exit_task | |
3201 | * see the comment there. | |
3202 | * | |
3203 | * 2) there is a lock-inversion with mmap_sem through | |
3204 | * perf_event_read_group(), which takes faults while | |
3205 | * holding ctx->mutex, however this is called after | |
3206 | * the last filedesc died, so there is no possibility | |
3207 | * to trigger the AB-BA case. | |
3208 | */ | |
3209 | mutex_lock_nested(&ctx->mutex, SINGLE_DEPTH_NESTING); | |
050735b0 | 3210 | raw_spin_lock_irq(&ctx->lock); |
8a49542c | 3211 | perf_group_detach(event); |
050735b0 | 3212 | raw_spin_unlock_irq(&ctx->lock); |
e03a9a55 | 3213 | perf_remove_from_context(event); |
d859e29f | 3214 | mutex_unlock(&ctx->mutex); |
0793a61d | 3215 | |
cdd6c482 | 3216 | free_event(event); |
0793a61d TG |
3217 | |
3218 | return 0; | |
3219 | } | |
a66a3052 | 3220 | EXPORT_SYMBOL_GPL(perf_event_release_kernel); |
0793a61d | 3221 | |
a66a3052 PZ |
3222 | /* |
3223 | * Called when the last reference to the file is gone. | |
3224 | */ | |
a6fa941d | 3225 | static void put_event(struct perf_event *event) |
fb0459d7 | 3226 | { |
8882135b | 3227 | struct task_struct *owner; |
fb0459d7 | 3228 | |
a6fa941d AV |
3229 | if (!atomic_long_dec_and_test(&event->refcount)) |
3230 | return; | |
fb0459d7 | 3231 | |
8882135b PZ |
3232 | rcu_read_lock(); |
3233 | owner = ACCESS_ONCE(event->owner); | |
3234 | /* | |
3235 | * Matches the smp_wmb() in perf_event_exit_task(). If we observe | |
3236 | * !owner it means the list deletion is complete and we can indeed | |
3237 | * free this event, otherwise we need to serialize on | |
3238 | * owner->perf_event_mutex. | |
3239 | */ | |
3240 | smp_read_barrier_depends(); | |
3241 | if (owner) { | |
3242 | /* | |
3243 | * Since delayed_put_task_struct() also drops the last | |
3244 | * task reference we can safely take a new reference | |
3245 | * while holding the rcu_read_lock(). | |
3246 | */ | |
3247 | get_task_struct(owner); | |
3248 | } | |
3249 | rcu_read_unlock(); | |
3250 | ||
3251 | if (owner) { | |
3252 | mutex_lock(&owner->perf_event_mutex); | |
3253 | /* | |
3254 | * We have to re-check the event->owner field, if it is cleared | |
3255 | * we raced with perf_event_exit_task(), acquiring the mutex | |
3256 | * ensured they're done, and we can proceed with freeing the | |
3257 | * event. | |
3258 | */ | |
3259 | if (event->owner) | |
3260 | list_del_init(&event->owner_entry); | |
3261 | mutex_unlock(&owner->perf_event_mutex); | |
3262 | put_task_struct(owner); | |
3263 | } | |
3264 | ||
a6fa941d AV |
3265 | perf_event_release_kernel(event); |
3266 | } | |
3267 | ||
3268 | static int perf_release(struct inode *inode, struct file *file) | |
3269 | { | |
3270 | put_event(file->private_data); | |
3271 | return 0; | |
fb0459d7 | 3272 | } |
fb0459d7 | 3273 | |
59ed446f | 3274 | u64 perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) |
e53c0994 | 3275 | { |
cdd6c482 | 3276 | struct perf_event *child; |
e53c0994 PZ |
3277 | u64 total = 0; |
3278 | ||
59ed446f PZ |
3279 | *enabled = 0; |
3280 | *running = 0; | |
3281 | ||
6f10581a | 3282 | mutex_lock(&event->child_mutex); |
cdd6c482 | 3283 | total += perf_event_read(event); |
59ed446f PZ |
3284 | *enabled += event->total_time_enabled + |
3285 | atomic64_read(&event->child_total_time_enabled); | |
3286 | *running += event->total_time_running + | |
3287 | atomic64_read(&event->child_total_time_running); | |
3288 | ||
3289 | list_for_each_entry(child, &event->child_list, child_list) { | |
cdd6c482 | 3290 | total += perf_event_read(child); |
59ed446f PZ |
3291 | *enabled += child->total_time_enabled; |
3292 | *running += child->total_time_running; | |
3293 | } | |
6f10581a | 3294 | mutex_unlock(&event->child_mutex); |
e53c0994 PZ |
3295 | |
3296 | return total; | |
3297 | } | |
fb0459d7 | 3298 | EXPORT_SYMBOL_GPL(perf_event_read_value); |
e53c0994 | 3299 | |
cdd6c482 | 3300 | static int perf_event_read_group(struct perf_event *event, |
3dab77fb PZ |
3301 | u64 read_format, char __user *buf) |
3302 | { | |
cdd6c482 | 3303 | struct perf_event *leader = event->group_leader, *sub; |
6f10581a PZ |
3304 | int n = 0, size = 0, ret = -EFAULT; |
3305 | struct perf_event_context *ctx = leader->ctx; | |
abf4868b | 3306 | u64 values[5]; |
59ed446f | 3307 | u64 count, enabled, running; |
abf4868b | 3308 | |
6f10581a | 3309 | mutex_lock(&ctx->mutex); |
59ed446f | 3310 | count = perf_event_read_value(leader, &enabled, &running); |
3dab77fb PZ |
3311 | |
3312 | values[n++] = 1 + leader->nr_siblings; | |
59ed446f PZ |
3313 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) |
3314 | values[n++] = enabled; | |
3315 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
3316 | values[n++] = running; | |
abf4868b PZ |
3317 | values[n++] = count; |
3318 | if (read_format & PERF_FORMAT_ID) | |
3319 | values[n++] = primary_event_id(leader); | |
3dab77fb PZ |
3320 | |
3321 | size = n * sizeof(u64); | |
3322 | ||
3323 | if (copy_to_user(buf, values, size)) | |
6f10581a | 3324 | goto unlock; |
3dab77fb | 3325 | |
6f10581a | 3326 | ret = size; |
3dab77fb | 3327 | |
65abc865 | 3328 | list_for_each_entry(sub, &leader->sibling_list, group_entry) { |
abf4868b | 3329 | n = 0; |
3dab77fb | 3330 | |
59ed446f | 3331 | values[n++] = perf_event_read_value(sub, &enabled, &running); |
abf4868b PZ |
3332 | if (read_format & PERF_FORMAT_ID) |
3333 | values[n++] = primary_event_id(sub); | |
3334 | ||
3335 | size = n * sizeof(u64); | |
3336 | ||
184d3da8 | 3337 | if (copy_to_user(buf + ret, values, size)) { |
6f10581a PZ |
3338 | ret = -EFAULT; |
3339 | goto unlock; | |
3340 | } | |
abf4868b PZ |
3341 | |
3342 | ret += size; | |
3dab77fb | 3343 | } |
6f10581a PZ |
3344 | unlock: |
3345 | mutex_unlock(&ctx->mutex); | |
3dab77fb | 3346 | |
abf4868b | 3347 | return ret; |
3dab77fb PZ |
3348 | } |
3349 | ||
cdd6c482 | 3350 | static int perf_event_read_one(struct perf_event *event, |
3dab77fb PZ |
3351 | u64 read_format, char __user *buf) |
3352 | { | |
59ed446f | 3353 | u64 enabled, running; |
3dab77fb PZ |
3354 | u64 values[4]; |
3355 | int n = 0; | |
3356 | ||
59ed446f PZ |
3357 | values[n++] = perf_event_read_value(event, &enabled, &running); |
3358 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
3359 | values[n++] = enabled; | |
3360 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
3361 | values[n++] = running; | |
3dab77fb | 3362 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 3363 | values[n++] = primary_event_id(event); |
3dab77fb PZ |
3364 | |
3365 | if (copy_to_user(buf, values, n * sizeof(u64))) | |
3366 | return -EFAULT; | |
3367 | ||
3368 | return n * sizeof(u64); | |
3369 | } | |
3370 | ||
0793a61d | 3371 | /* |
cdd6c482 | 3372 | * Read the performance event - simple non blocking version for now |
0793a61d TG |
3373 | */ |
3374 | static ssize_t | |
cdd6c482 | 3375 | perf_read_hw(struct perf_event *event, char __user *buf, size_t count) |
0793a61d | 3376 | { |
cdd6c482 | 3377 | u64 read_format = event->attr.read_format; |
3dab77fb | 3378 | int ret; |
0793a61d | 3379 | |
3b6f9e5c | 3380 | /* |
cdd6c482 | 3381 | * Return end-of-file for a read on a event that is in |
3b6f9e5c PM |
3382 | * error state (i.e. because it was pinned but it couldn't be |
3383 | * scheduled on to the CPU at some point). | |
3384 | */ | |
cdd6c482 | 3385 | if (event->state == PERF_EVENT_STATE_ERROR) |
3b6f9e5c PM |
3386 | return 0; |
3387 | ||
c320c7b7 | 3388 | if (count < event->read_size) |
3dab77fb PZ |
3389 | return -ENOSPC; |
3390 | ||
cdd6c482 | 3391 | WARN_ON_ONCE(event->ctx->parent_ctx); |
3dab77fb | 3392 | if (read_format & PERF_FORMAT_GROUP) |
cdd6c482 | 3393 | ret = perf_event_read_group(event, read_format, buf); |
3dab77fb | 3394 | else |
cdd6c482 | 3395 | ret = perf_event_read_one(event, read_format, buf); |
0793a61d | 3396 | |
3dab77fb | 3397 | return ret; |
0793a61d TG |
3398 | } |
3399 | ||
0793a61d TG |
3400 | static ssize_t |
3401 | perf_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) | |
3402 | { | |
cdd6c482 | 3403 | struct perf_event *event = file->private_data; |
0793a61d | 3404 | |
cdd6c482 | 3405 | return perf_read_hw(event, buf, count); |
0793a61d TG |
3406 | } |
3407 | ||
3408 | static unsigned int perf_poll(struct file *file, poll_table *wait) | |
3409 | { | |
cdd6c482 | 3410 | struct perf_event *event = file->private_data; |
76369139 | 3411 | struct ring_buffer *rb; |
c33a0bc4 | 3412 | unsigned int events = POLL_HUP; |
c7138f37 | 3413 | |
10c6db11 | 3414 | /* |
9bb5d40c PZ |
3415 | * Pin the event->rb by taking event->mmap_mutex; otherwise |
3416 | * perf_event_set_output() can swizzle our rb and make us miss wakeups. | |
10c6db11 PZ |
3417 | */ |
3418 | mutex_lock(&event->mmap_mutex); | |
9bb5d40c PZ |
3419 | rb = event->rb; |
3420 | if (rb) | |
76369139 | 3421 | events = atomic_xchg(&rb->poll, 0); |
10c6db11 PZ |
3422 | mutex_unlock(&event->mmap_mutex); |
3423 | ||
cdd6c482 | 3424 | poll_wait(file, &event->waitq, wait); |
0793a61d | 3425 | |
0793a61d TG |
3426 | return events; |
3427 | } | |
3428 | ||
cdd6c482 | 3429 | static void perf_event_reset(struct perf_event *event) |
6de6a7b9 | 3430 | { |
cdd6c482 | 3431 | (void)perf_event_read(event); |
e7850595 | 3432 | local64_set(&event->count, 0); |
cdd6c482 | 3433 | perf_event_update_userpage(event); |
3df5edad PZ |
3434 | } |
3435 | ||
c93f7669 | 3436 | /* |
cdd6c482 IM |
3437 | * Holding the top-level event's child_mutex means that any |
3438 | * descendant process that has inherited this event will block | |
3439 | * in sync_child_event if it goes to exit, thus satisfying the | |
3440 | * task existence requirements of perf_event_enable/disable. | |
c93f7669 | 3441 | */ |
cdd6c482 IM |
3442 | static void perf_event_for_each_child(struct perf_event *event, |
3443 | void (*func)(struct perf_event *)) | |
3df5edad | 3444 | { |
cdd6c482 | 3445 | struct perf_event *child; |
3df5edad | 3446 | |
cdd6c482 IM |
3447 | WARN_ON_ONCE(event->ctx->parent_ctx); |
3448 | mutex_lock(&event->child_mutex); | |
3449 | func(event); | |
3450 | list_for_each_entry(child, &event->child_list, child_list) | |
3df5edad | 3451 | func(child); |
cdd6c482 | 3452 | mutex_unlock(&event->child_mutex); |
3df5edad PZ |
3453 | } |
3454 | ||
cdd6c482 IM |
3455 | static void perf_event_for_each(struct perf_event *event, |
3456 | void (*func)(struct perf_event *)) | |
3df5edad | 3457 | { |
cdd6c482 IM |
3458 | struct perf_event_context *ctx = event->ctx; |
3459 | struct perf_event *sibling; | |
3df5edad | 3460 | |
75f937f2 PZ |
3461 | WARN_ON_ONCE(ctx->parent_ctx); |
3462 | mutex_lock(&ctx->mutex); | |
cdd6c482 | 3463 | event = event->group_leader; |
75f937f2 | 3464 | |
cdd6c482 | 3465 | perf_event_for_each_child(event, func); |
cdd6c482 | 3466 | list_for_each_entry(sibling, &event->sibling_list, group_entry) |
724b6daa | 3467 | perf_event_for_each_child(sibling, func); |
75f937f2 | 3468 | mutex_unlock(&ctx->mutex); |
6de6a7b9 PZ |
3469 | } |
3470 | ||
cdd6c482 | 3471 | static int perf_event_period(struct perf_event *event, u64 __user *arg) |
08247e31 | 3472 | { |
cdd6c482 | 3473 | struct perf_event_context *ctx = event->ctx; |
08247e31 PZ |
3474 | int ret = 0; |
3475 | u64 value; | |
3476 | ||
6c7e550f | 3477 | if (!is_sampling_event(event)) |
08247e31 PZ |
3478 | return -EINVAL; |
3479 | ||
ad0cf347 | 3480 | if (copy_from_user(&value, arg, sizeof(value))) |
08247e31 PZ |
3481 | return -EFAULT; |
3482 | ||
3483 | if (!value) | |
3484 | return -EINVAL; | |
3485 | ||
e625cce1 | 3486 | raw_spin_lock_irq(&ctx->lock); |
cdd6c482 IM |
3487 | if (event->attr.freq) { |
3488 | if (value > sysctl_perf_event_sample_rate) { | |
08247e31 PZ |
3489 | ret = -EINVAL; |
3490 | goto unlock; | |
3491 | } | |
3492 | ||
cdd6c482 | 3493 | event->attr.sample_freq = value; |
08247e31 | 3494 | } else { |
cdd6c482 IM |
3495 | event->attr.sample_period = value; |
3496 | event->hw.sample_period = value; | |
08247e31 PZ |
3497 | } |
3498 | unlock: | |
e625cce1 | 3499 | raw_spin_unlock_irq(&ctx->lock); |
08247e31 PZ |
3500 | |
3501 | return ret; | |
3502 | } | |
3503 | ||
ac9721f3 PZ |
3504 | static const struct file_operations perf_fops; |
3505 | ||
2903ff01 | 3506 | static inline int perf_fget_light(int fd, struct fd *p) |
ac9721f3 | 3507 | { |
2903ff01 AV |
3508 | struct fd f = fdget(fd); |
3509 | if (!f.file) | |
3510 | return -EBADF; | |
ac9721f3 | 3511 | |
2903ff01 AV |
3512 | if (f.file->f_op != &perf_fops) { |
3513 | fdput(f); | |
3514 | return -EBADF; | |
ac9721f3 | 3515 | } |
2903ff01 AV |
3516 | *p = f; |
3517 | return 0; | |
ac9721f3 PZ |
3518 | } |
3519 | ||
3520 | static int perf_event_set_output(struct perf_event *event, | |
3521 | struct perf_event *output_event); | |
6fb2915d | 3522 | static int perf_event_set_filter(struct perf_event *event, void __user *arg); |
a4be7c27 | 3523 | |
d859e29f PM |
3524 | static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
3525 | { | |
cdd6c482 IM |
3526 | struct perf_event *event = file->private_data; |
3527 | void (*func)(struct perf_event *); | |
3df5edad | 3528 | u32 flags = arg; |
d859e29f PM |
3529 | |
3530 | switch (cmd) { | |
cdd6c482 IM |
3531 | case PERF_EVENT_IOC_ENABLE: |
3532 | func = perf_event_enable; | |
d859e29f | 3533 | break; |
cdd6c482 IM |
3534 | case PERF_EVENT_IOC_DISABLE: |
3535 | func = perf_event_disable; | |
79f14641 | 3536 | break; |
cdd6c482 IM |
3537 | case PERF_EVENT_IOC_RESET: |
3538 | func = perf_event_reset; | |
6de6a7b9 | 3539 | break; |
3df5edad | 3540 | |
cdd6c482 IM |
3541 | case PERF_EVENT_IOC_REFRESH: |
3542 | return perf_event_refresh(event, arg); | |
08247e31 | 3543 | |
cdd6c482 IM |
3544 | case PERF_EVENT_IOC_PERIOD: |
3545 | return perf_event_period(event, (u64 __user *)arg); | |
08247e31 | 3546 | |
cdd6c482 | 3547 | case PERF_EVENT_IOC_SET_OUTPUT: |
ac9721f3 | 3548 | { |
ac9721f3 | 3549 | int ret; |
ac9721f3 | 3550 | if (arg != -1) { |
2903ff01 AV |
3551 | struct perf_event *output_event; |
3552 | struct fd output; | |
3553 | ret = perf_fget_light(arg, &output); | |
3554 | if (ret) | |
3555 | return ret; | |
3556 | output_event = output.file->private_data; | |
3557 | ret = perf_event_set_output(event, output_event); | |
3558 | fdput(output); | |
3559 | } else { | |
3560 | ret = perf_event_set_output(event, NULL); | |
ac9721f3 | 3561 | } |
ac9721f3 PZ |
3562 | return ret; |
3563 | } | |
a4be7c27 | 3564 | |
6fb2915d LZ |
3565 | case PERF_EVENT_IOC_SET_FILTER: |
3566 | return perf_event_set_filter(event, (void __user *)arg); | |
3567 | ||
d859e29f | 3568 | default: |
3df5edad | 3569 | return -ENOTTY; |
d859e29f | 3570 | } |
3df5edad PZ |
3571 | |
3572 | if (flags & PERF_IOC_FLAG_GROUP) | |
cdd6c482 | 3573 | perf_event_for_each(event, func); |
3df5edad | 3574 | else |
cdd6c482 | 3575 | perf_event_for_each_child(event, func); |
3df5edad PZ |
3576 | |
3577 | return 0; | |
d859e29f PM |
3578 | } |
3579 | ||
cdd6c482 | 3580 | int perf_event_task_enable(void) |
771d7cde | 3581 | { |
cdd6c482 | 3582 | struct perf_event *event; |
771d7cde | 3583 | |
cdd6c482 IM |
3584 | mutex_lock(¤t->perf_event_mutex); |
3585 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) | |
3586 | perf_event_for_each_child(event, perf_event_enable); | |
3587 | mutex_unlock(¤t->perf_event_mutex); | |
771d7cde PZ |
3588 | |
3589 | return 0; | |
3590 | } | |
3591 | ||
cdd6c482 | 3592 | int perf_event_task_disable(void) |
771d7cde | 3593 | { |
cdd6c482 | 3594 | struct perf_event *event; |
771d7cde | 3595 | |
cdd6c482 IM |
3596 | mutex_lock(¤t->perf_event_mutex); |
3597 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) | |
3598 | perf_event_for_each_child(event, perf_event_disable); | |
3599 | mutex_unlock(¤t->perf_event_mutex); | |
771d7cde PZ |
3600 | |
3601 | return 0; | |
3602 | } | |
3603 | ||
cdd6c482 | 3604 | static int perf_event_index(struct perf_event *event) |
194002b2 | 3605 | { |
a4eaf7f1 PZ |
3606 | if (event->hw.state & PERF_HES_STOPPED) |
3607 | return 0; | |
3608 | ||
cdd6c482 | 3609 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
194002b2 PZ |
3610 | return 0; |
3611 | ||
35edc2a5 | 3612 | return event->pmu->event_idx(event); |
194002b2 PZ |
3613 | } |
3614 | ||
c4794295 | 3615 | static void calc_timer_values(struct perf_event *event, |
e3f3541c | 3616 | u64 *now, |
7f310a5d EM |
3617 | u64 *enabled, |
3618 | u64 *running) | |
c4794295 | 3619 | { |
e3f3541c | 3620 | u64 ctx_time; |
c4794295 | 3621 | |
e3f3541c PZ |
3622 | *now = perf_clock(); |
3623 | ctx_time = event->shadow_ctx_time + *now; | |
c4794295 EM |
3624 | *enabled = ctx_time - event->tstamp_enabled; |
3625 | *running = ctx_time - event->tstamp_running; | |
3626 | } | |
3627 | ||
c7206205 | 3628 | void __weak arch_perf_update_userpage(struct perf_event_mmap_page *userpg, u64 now) |
e3f3541c PZ |
3629 | { |
3630 | } | |
3631 | ||
38ff667b PZ |
3632 | /* |
3633 | * Callers need to ensure there can be no nesting of this function, otherwise | |
3634 | * the seqlock logic goes bad. We can not serialize this because the arch | |
3635 | * code calls this from NMI context. | |
3636 | */ | |
cdd6c482 | 3637 | void perf_event_update_userpage(struct perf_event *event) |
37d81828 | 3638 | { |
cdd6c482 | 3639 | struct perf_event_mmap_page *userpg; |
76369139 | 3640 | struct ring_buffer *rb; |
e3f3541c | 3641 | u64 enabled, running, now; |
38ff667b PZ |
3642 | |
3643 | rcu_read_lock(); | |
0d641208 EM |
3644 | /* |
3645 | * compute total_time_enabled, total_time_running | |
3646 | * based on snapshot values taken when the event | |
3647 | * was last scheduled in. | |
3648 | * | |
3649 | * we cannot simply called update_context_time() | |
3650 | * because of locking issue as we can be called in | |
3651 | * NMI context | |
3652 | */ | |
e3f3541c | 3653 | calc_timer_values(event, &now, &enabled, &running); |
76369139 FW |
3654 | rb = rcu_dereference(event->rb); |
3655 | if (!rb) | |
38ff667b PZ |
3656 | goto unlock; |
3657 | ||
76369139 | 3658 | userpg = rb->user_page; |
37d81828 | 3659 | |
7b732a75 PZ |
3660 | /* |
3661 | * Disable preemption so as to not let the corresponding user-space | |
3662 | * spin too long if we get preempted. | |
3663 | */ | |
3664 | preempt_disable(); | |
37d81828 | 3665 | ++userpg->lock; |
92f22a38 | 3666 | barrier(); |
cdd6c482 | 3667 | userpg->index = perf_event_index(event); |
b5e58793 | 3668 | userpg->offset = perf_event_count(event); |
365a4038 | 3669 | if (userpg->index) |
e7850595 | 3670 | userpg->offset -= local64_read(&event->hw.prev_count); |
7b732a75 | 3671 | |
0d641208 | 3672 | userpg->time_enabled = enabled + |
cdd6c482 | 3673 | atomic64_read(&event->child_total_time_enabled); |
7f8b4e4e | 3674 | |
0d641208 | 3675 | userpg->time_running = running + |
cdd6c482 | 3676 | atomic64_read(&event->child_total_time_running); |
7f8b4e4e | 3677 | |
c7206205 | 3678 | arch_perf_update_userpage(userpg, now); |
e3f3541c | 3679 | |
92f22a38 | 3680 | barrier(); |
37d81828 | 3681 | ++userpg->lock; |
7b732a75 | 3682 | preempt_enable(); |
38ff667b | 3683 | unlock: |
7b732a75 | 3684 | rcu_read_unlock(); |
37d81828 PM |
3685 | } |
3686 | ||
906010b2 PZ |
3687 | static int perf_mmap_fault(struct vm_area_struct *vma, struct vm_fault *vmf) |
3688 | { | |
3689 | struct perf_event *event = vma->vm_file->private_data; | |
76369139 | 3690 | struct ring_buffer *rb; |
906010b2 PZ |
3691 | int ret = VM_FAULT_SIGBUS; |
3692 | ||
3693 | if (vmf->flags & FAULT_FLAG_MKWRITE) { | |
3694 | if (vmf->pgoff == 0) | |
3695 | ret = 0; | |
3696 | return ret; | |
3697 | } | |
3698 | ||
3699 | rcu_read_lock(); | |
76369139 FW |
3700 | rb = rcu_dereference(event->rb); |
3701 | if (!rb) | |
906010b2 PZ |
3702 | goto unlock; |
3703 | ||
3704 | if (vmf->pgoff && (vmf->flags & FAULT_FLAG_WRITE)) | |
3705 | goto unlock; | |
3706 | ||
76369139 | 3707 | vmf->page = perf_mmap_to_page(rb, vmf->pgoff); |
906010b2 PZ |
3708 | if (!vmf->page) |
3709 | goto unlock; | |
3710 | ||
3711 | get_page(vmf->page); | |
3712 | vmf->page->mapping = vma->vm_file->f_mapping; | |
3713 | vmf->page->index = vmf->pgoff; | |
3714 | ||
3715 | ret = 0; | |
3716 | unlock: | |
3717 | rcu_read_unlock(); | |
3718 | ||
3719 | return ret; | |
3720 | } | |
3721 | ||
10c6db11 PZ |
3722 | static void ring_buffer_attach(struct perf_event *event, |
3723 | struct ring_buffer *rb) | |
3724 | { | |
3725 | unsigned long flags; | |
3726 | ||
3727 | if (!list_empty(&event->rb_entry)) | |
3728 | return; | |
3729 | ||
3730 | spin_lock_irqsave(&rb->event_lock, flags); | |
9bb5d40c PZ |
3731 | if (list_empty(&event->rb_entry)) |
3732 | list_add(&event->rb_entry, &rb->event_list); | |
10c6db11 PZ |
3733 | spin_unlock_irqrestore(&rb->event_lock, flags); |
3734 | } | |
3735 | ||
9bb5d40c | 3736 | static void ring_buffer_detach(struct perf_event *event, struct ring_buffer *rb) |
10c6db11 PZ |
3737 | { |
3738 | unsigned long flags; | |
3739 | ||
3740 | if (list_empty(&event->rb_entry)) | |
3741 | return; | |
3742 | ||
3743 | spin_lock_irqsave(&rb->event_lock, flags); | |
3744 | list_del_init(&event->rb_entry); | |
3745 | wake_up_all(&event->waitq); | |
3746 | spin_unlock_irqrestore(&rb->event_lock, flags); | |
3747 | } | |
3748 | ||
3749 | static void ring_buffer_wakeup(struct perf_event *event) | |
3750 | { | |
3751 | struct ring_buffer *rb; | |
3752 | ||
3753 | rcu_read_lock(); | |
3754 | rb = rcu_dereference(event->rb); | |
9bb5d40c PZ |
3755 | if (rb) { |
3756 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) | |
3757 | wake_up_all(&event->waitq); | |
3758 | } | |
10c6db11 PZ |
3759 | rcu_read_unlock(); |
3760 | } | |
3761 | ||
76369139 | 3762 | static void rb_free_rcu(struct rcu_head *rcu_head) |
906010b2 | 3763 | { |
76369139 | 3764 | struct ring_buffer *rb; |
906010b2 | 3765 | |
76369139 FW |
3766 | rb = container_of(rcu_head, struct ring_buffer, rcu_head); |
3767 | rb_free(rb); | |
7b732a75 PZ |
3768 | } |
3769 | ||
76369139 | 3770 | static struct ring_buffer *ring_buffer_get(struct perf_event *event) |
7b732a75 | 3771 | { |
76369139 | 3772 | struct ring_buffer *rb; |
7b732a75 | 3773 | |
ac9721f3 | 3774 | rcu_read_lock(); |
76369139 FW |
3775 | rb = rcu_dereference(event->rb); |
3776 | if (rb) { | |
3777 | if (!atomic_inc_not_zero(&rb->refcount)) | |
3778 | rb = NULL; | |
ac9721f3 PZ |
3779 | } |
3780 | rcu_read_unlock(); | |
3781 | ||
76369139 | 3782 | return rb; |
ac9721f3 PZ |
3783 | } |
3784 | ||
76369139 | 3785 | static void ring_buffer_put(struct ring_buffer *rb) |
ac9721f3 | 3786 | { |
76369139 | 3787 | if (!atomic_dec_and_test(&rb->refcount)) |
ac9721f3 | 3788 | return; |
7b732a75 | 3789 | |
9bb5d40c | 3790 | WARN_ON_ONCE(!list_empty(&rb->event_list)); |
10c6db11 | 3791 | |
76369139 | 3792 | call_rcu(&rb->rcu_head, rb_free_rcu); |
7b732a75 PZ |
3793 | } |
3794 | ||
3795 | static void perf_mmap_open(struct vm_area_struct *vma) | |
3796 | { | |
cdd6c482 | 3797 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 3798 | |
cdd6c482 | 3799 | atomic_inc(&event->mmap_count); |
9bb5d40c | 3800 | atomic_inc(&event->rb->mmap_count); |
7b732a75 PZ |
3801 | } |
3802 | ||
9bb5d40c PZ |
3803 | /* |
3804 | * A buffer can be mmap()ed multiple times; either directly through the same | |
3805 | * event, or through other events by use of perf_event_set_output(). | |
3806 | * | |
3807 | * In order to undo the VM accounting done by perf_mmap() we need to destroy | |
3808 | * the buffer here, where we still have a VM context. This means we need | |
3809 | * to detach all events redirecting to us. | |
3810 | */ | |
7b732a75 PZ |
3811 | static void perf_mmap_close(struct vm_area_struct *vma) |
3812 | { | |
cdd6c482 | 3813 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 3814 | |
9bb5d40c PZ |
3815 | struct ring_buffer *rb = event->rb; |
3816 | struct user_struct *mmap_user = rb->mmap_user; | |
3817 | int mmap_locked = rb->mmap_locked; | |
3818 | unsigned long size = perf_data_size(rb); | |
789f90fc | 3819 | |
9bb5d40c PZ |
3820 | atomic_dec(&rb->mmap_count); |
3821 | ||
3822 | if (!atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex)) | |
3823 | return; | |
3824 | ||
3825 | /* Detach current event from the buffer. */ | |
3826 | rcu_assign_pointer(event->rb, NULL); | |
3827 | ring_buffer_detach(event, rb); | |
3828 | mutex_unlock(&event->mmap_mutex); | |
3829 | ||
3830 | /* If there's still other mmap()s of this buffer, we're done. */ | |
3831 | if (atomic_read(&rb->mmap_count)) { | |
3832 | ring_buffer_put(rb); /* can't be last */ | |
3833 | return; | |
3834 | } | |
ac9721f3 | 3835 | |
9bb5d40c PZ |
3836 | /* |
3837 | * No other mmap()s, detach from all other events that might redirect | |
3838 | * into the now unreachable buffer. Somewhat complicated by the | |
3839 | * fact that rb::event_lock otherwise nests inside mmap_mutex. | |
3840 | */ | |
3841 | again: | |
3842 | rcu_read_lock(); | |
3843 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) { | |
3844 | if (!atomic_long_inc_not_zero(&event->refcount)) { | |
3845 | /* | |
3846 | * This event is en-route to free_event() which will | |
3847 | * detach it and remove it from the list. | |
3848 | */ | |
3849 | continue; | |
3850 | } | |
3851 | rcu_read_unlock(); | |
789f90fc | 3852 | |
9bb5d40c PZ |
3853 | mutex_lock(&event->mmap_mutex); |
3854 | /* | |
3855 | * Check we didn't race with perf_event_set_output() which can | |
3856 | * swizzle the rb from under us while we were waiting to | |
3857 | * acquire mmap_mutex. | |
3858 | * | |
3859 | * If we find a different rb; ignore this event, a next | |
3860 | * iteration will no longer find it on the list. We have to | |
3861 | * still restart the iteration to make sure we're not now | |
3862 | * iterating the wrong list. | |
3863 | */ | |
3864 | if (event->rb == rb) { | |
3865 | rcu_assign_pointer(event->rb, NULL); | |
3866 | ring_buffer_detach(event, rb); | |
3867 | ring_buffer_put(rb); /* can't be last, we still have one */ | |
26cb63ad | 3868 | } |
cdd6c482 | 3869 | mutex_unlock(&event->mmap_mutex); |
9bb5d40c | 3870 | put_event(event); |
ac9721f3 | 3871 | |
9bb5d40c PZ |
3872 | /* |
3873 | * Restart the iteration; either we're on the wrong list or | |
3874 | * destroyed its integrity by doing a deletion. | |
3875 | */ | |
3876 | goto again; | |
7b732a75 | 3877 | } |
9bb5d40c PZ |
3878 | rcu_read_unlock(); |
3879 | ||
3880 | /* | |
3881 | * It could be there's still a few 0-ref events on the list; they'll | |
3882 | * get cleaned up by free_event() -- they'll also still have their | |
3883 | * ref on the rb and will free it whenever they are done with it. | |
3884 | * | |
3885 | * Aside from that, this buffer is 'fully' detached and unmapped, | |
3886 | * undo the VM accounting. | |
3887 | */ | |
3888 | ||
3889 | atomic_long_sub((size >> PAGE_SHIFT) + 1, &mmap_user->locked_vm); | |
3890 | vma->vm_mm->pinned_vm -= mmap_locked; | |
3891 | free_uid(mmap_user); | |
3892 | ||
3893 | ring_buffer_put(rb); /* could be last */ | |
37d81828 PM |
3894 | } |
3895 | ||
f0f37e2f | 3896 | static const struct vm_operations_struct perf_mmap_vmops = { |
43a21ea8 PZ |
3897 | .open = perf_mmap_open, |
3898 | .close = perf_mmap_close, | |
3899 | .fault = perf_mmap_fault, | |
3900 | .page_mkwrite = perf_mmap_fault, | |
37d81828 PM |
3901 | }; |
3902 | ||
3903 | static int perf_mmap(struct file *file, struct vm_area_struct *vma) | |
3904 | { | |
cdd6c482 | 3905 | struct perf_event *event = file->private_data; |
22a4f650 | 3906 | unsigned long user_locked, user_lock_limit; |
789f90fc | 3907 | struct user_struct *user = current_user(); |
22a4f650 | 3908 | unsigned long locked, lock_limit; |
76369139 | 3909 | struct ring_buffer *rb; |
7b732a75 PZ |
3910 | unsigned long vma_size; |
3911 | unsigned long nr_pages; | |
789f90fc | 3912 | long user_extra, extra; |
d57e34fd | 3913 | int ret = 0, flags = 0; |
37d81828 | 3914 | |
c7920614 PZ |
3915 | /* |
3916 | * Don't allow mmap() of inherited per-task counters. This would | |
3917 | * create a performance issue due to all children writing to the | |
76369139 | 3918 | * same rb. |
c7920614 PZ |
3919 | */ |
3920 | if (event->cpu == -1 && event->attr.inherit) | |
3921 | return -EINVAL; | |
3922 | ||
43a21ea8 | 3923 | if (!(vma->vm_flags & VM_SHARED)) |
37d81828 | 3924 | return -EINVAL; |
7b732a75 PZ |
3925 | |
3926 | vma_size = vma->vm_end - vma->vm_start; | |
3927 | nr_pages = (vma_size / PAGE_SIZE) - 1; | |
3928 | ||
7730d865 | 3929 | /* |
76369139 | 3930 | * If we have rb pages ensure they're a power-of-two number, so we |
7730d865 PZ |
3931 | * can do bitmasks instead of modulo. |
3932 | */ | |
3933 | if (nr_pages != 0 && !is_power_of_2(nr_pages)) | |
37d81828 PM |
3934 | return -EINVAL; |
3935 | ||
7b732a75 | 3936 | if (vma_size != PAGE_SIZE * (1 + nr_pages)) |
37d81828 PM |
3937 | return -EINVAL; |
3938 | ||
7b732a75 PZ |
3939 | if (vma->vm_pgoff != 0) |
3940 | return -EINVAL; | |
37d81828 | 3941 | |
cdd6c482 | 3942 | WARN_ON_ONCE(event->ctx->parent_ctx); |
9bb5d40c | 3943 | again: |
cdd6c482 | 3944 | mutex_lock(&event->mmap_mutex); |
76369139 | 3945 | if (event->rb) { |
9bb5d40c | 3946 | if (event->rb->nr_pages != nr_pages) { |
ebb3c4c4 | 3947 | ret = -EINVAL; |
9bb5d40c PZ |
3948 | goto unlock; |
3949 | } | |
3950 | ||
3951 | if (!atomic_inc_not_zero(&event->rb->mmap_count)) { | |
3952 | /* | |
3953 | * Raced against perf_mmap_close() through | |
3954 | * perf_event_set_output(). Try again, hope for better | |
3955 | * luck. | |
3956 | */ | |
3957 | mutex_unlock(&event->mmap_mutex); | |
3958 | goto again; | |
3959 | } | |
3960 | ||
ebb3c4c4 PZ |
3961 | goto unlock; |
3962 | } | |
3963 | ||
789f90fc | 3964 | user_extra = nr_pages + 1; |
cdd6c482 | 3965 | user_lock_limit = sysctl_perf_event_mlock >> (PAGE_SHIFT - 10); |
a3862d3f IM |
3966 | |
3967 | /* | |
3968 | * Increase the limit linearly with more CPUs: | |
3969 | */ | |
3970 | user_lock_limit *= num_online_cpus(); | |
3971 | ||
789f90fc | 3972 | user_locked = atomic_long_read(&user->locked_vm) + user_extra; |
c5078f78 | 3973 | |
789f90fc PZ |
3974 | extra = 0; |
3975 | if (user_locked > user_lock_limit) | |
3976 | extra = user_locked - user_lock_limit; | |
7b732a75 | 3977 | |
78d7d407 | 3978 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
7b732a75 | 3979 | lock_limit >>= PAGE_SHIFT; |
bc3e53f6 | 3980 | locked = vma->vm_mm->pinned_vm + extra; |
7b732a75 | 3981 | |
459ec28a IM |
3982 | if ((locked > lock_limit) && perf_paranoid_tracepoint_raw() && |
3983 | !capable(CAP_IPC_LOCK)) { | |
ebb3c4c4 PZ |
3984 | ret = -EPERM; |
3985 | goto unlock; | |
3986 | } | |
7b732a75 | 3987 | |
76369139 | 3988 | WARN_ON(event->rb); |
906010b2 | 3989 | |
d57e34fd | 3990 | if (vma->vm_flags & VM_WRITE) |
76369139 | 3991 | flags |= RING_BUFFER_WRITABLE; |
d57e34fd | 3992 | |
4ec8363d VW |
3993 | rb = rb_alloc(nr_pages, |
3994 | event->attr.watermark ? event->attr.wakeup_watermark : 0, | |
3995 | event->cpu, flags); | |
3996 | ||
76369139 | 3997 | if (!rb) { |
ac9721f3 | 3998 | ret = -ENOMEM; |
ebb3c4c4 | 3999 | goto unlock; |
ac9721f3 | 4000 | } |
26cb63ad | 4001 | |
9bb5d40c | 4002 | atomic_set(&rb->mmap_count, 1); |
26cb63ad PZ |
4003 | rb->mmap_locked = extra; |
4004 | rb->mmap_user = get_current_user(); | |
43a21ea8 | 4005 | |
ac9721f3 | 4006 | atomic_long_add(user_extra, &user->locked_vm); |
26cb63ad PZ |
4007 | vma->vm_mm->pinned_vm += extra; |
4008 | ||
9bb5d40c | 4009 | ring_buffer_attach(event, rb); |
26cb63ad | 4010 | rcu_assign_pointer(event->rb, rb); |
ac9721f3 | 4011 | |
9a0f05cb PZ |
4012 | perf_event_update_userpage(event); |
4013 | ||
ebb3c4c4 | 4014 | unlock: |
ac9721f3 PZ |
4015 | if (!ret) |
4016 | atomic_inc(&event->mmap_count); | |
cdd6c482 | 4017 | mutex_unlock(&event->mmap_mutex); |
37d81828 | 4018 | |
9bb5d40c PZ |
4019 | /* |
4020 | * Since pinned accounting is per vm we cannot allow fork() to copy our | |
4021 | * vma. | |
4022 | */ | |
26cb63ad | 4023 | vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND | VM_DONTDUMP; |
37d81828 | 4024 | vma->vm_ops = &perf_mmap_vmops; |
7b732a75 PZ |
4025 | |
4026 | return ret; | |
37d81828 PM |
4027 | } |
4028 | ||
3c446b3d PZ |
4029 | static int perf_fasync(int fd, struct file *filp, int on) |
4030 | { | |
496ad9aa | 4031 | struct inode *inode = file_inode(filp); |
cdd6c482 | 4032 | struct perf_event *event = filp->private_data; |
3c446b3d PZ |
4033 | int retval; |
4034 | ||
4035 | mutex_lock(&inode->i_mutex); | |
cdd6c482 | 4036 | retval = fasync_helper(fd, filp, on, &event->fasync); |
3c446b3d PZ |
4037 | mutex_unlock(&inode->i_mutex); |
4038 | ||
4039 | if (retval < 0) | |
4040 | return retval; | |
4041 | ||
4042 | return 0; | |
4043 | } | |
4044 | ||
0793a61d | 4045 | static const struct file_operations perf_fops = { |
3326c1ce | 4046 | .llseek = no_llseek, |
0793a61d TG |
4047 | .release = perf_release, |
4048 | .read = perf_read, | |
4049 | .poll = perf_poll, | |
d859e29f PM |
4050 | .unlocked_ioctl = perf_ioctl, |
4051 | .compat_ioctl = perf_ioctl, | |
37d81828 | 4052 | .mmap = perf_mmap, |
3c446b3d | 4053 | .fasync = perf_fasync, |
0793a61d TG |
4054 | }; |
4055 | ||
925d519a | 4056 | /* |
cdd6c482 | 4057 | * Perf event wakeup |
925d519a PZ |
4058 | * |
4059 | * If there's data, ensure we set the poll() state and publish everything | |
4060 | * to user-space before waking everybody up. | |
4061 | */ | |
4062 | ||
cdd6c482 | 4063 | void perf_event_wakeup(struct perf_event *event) |
925d519a | 4064 | { |
10c6db11 | 4065 | ring_buffer_wakeup(event); |
4c9e2542 | 4066 | |
cdd6c482 IM |
4067 | if (event->pending_kill) { |
4068 | kill_fasync(&event->fasync, SIGIO, event->pending_kill); | |
4069 | event->pending_kill = 0; | |
4c9e2542 | 4070 | } |
925d519a PZ |
4071 | } |
4072 | ||
e360adbe | 4073 | static void perf_pending_event(struct irq_work *entry) |
79f14641 | 4074 | { |
cdd6c482 IM |
4075 | struct perf_event *event = container_of(entry, |
4076 | struct perf_event, pending); | |
79f14641 | 4077 | |
cdd6c482 IM |
4078 | if (event->pending_disable) { |
4079 | event->pending_disable = 0; | |
4080 | __perf_event_disable(event); | |
79f14641 PZ |
4081 | } |
4082 | ||
cdd6c482 IM |
4083 | if (event->pending_wakeup) { |
4084 | event->pending_wakeup = 0; | |
4085 | perf_event_wakeup(event); | |
79f14641 PZ |
4086 | } |
4087 | } | |
4088 | ||
39447b38 ZY |
4089 | /* |
4090 | * We assume there is only KVM supporting the callbacks. | |
4091 | * Later on, we might change it to a list if there is | |
4092 | * another virtualization implementation supporting the callbacks. | |
4093 | */ | |
4094 | struct perf_guest_info_callbacks *perf_guest_cbs; | |
4095 | ||
4096 | int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
4097 | { | |
4098 | perf_guest_cbs = cbs; | |
4099 | return 0; | |
4100 | } | |
4101 | EXPORT_SYMBOL_GPL(perf_register_guest_info_callbacks); | |
4102 | ||
4103 | int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
4104 | { | |
4105 | perf_guest_cbs = NULL; | |
4106 | return 0; | |
4107 | } | |
4108 | EXPORT_SYMBOL_GPL(perf_unregister_guest_info_callbacks); | |
4109 | ||
4018994f JO |
4110 | static void |
4111 | perf_output_sample_regs(struct perf_output_handle *handle, | |
4112 | struct pt_regs *regs, u64 mask) | |
4113 | { | |
4114 | int bit; | |
4115 | ||
4116 | for_each_set_bit(bit, (const unsigned long *) &mask, | |
4117 | sizeof(mask) * BITS_PER_BYTE) { | |
4118 | u64 val; | |
4119 | ||
4120 | val = perf_reg_value(regs, bit); | |
4121 | perf_output_put(handle, val); | |
4122 | } | |
4123 | } | |
4124 | ||
4125 | static void perf_sample_regs_user(struct perf_regs_user *regs_user, | |
4126 | struct pt_regs *regs) | |
4127 | { | |
4128 | if (!user_mode(regs)) { | |
4129 | if (current->mm) | |
4130 | regs = task_pt_regs(current); | |
4131 | else | |
4132 | regs = NULL; | |
4133 | } | |
4134 | ||
4135 | if (regs) { | |
4136 | regs_user->regs = regs; | |
4137 | regs_user->abi = perf_reg_abi(current); | |
4138 | } | |
4139 | } | |
4140 | ||
c5ebcedb JO |
4141 | /* |
4142 | * Get remaining task size from user stack pointer. | |
4143 | * | |
4144 | * It'd be better to take stack vma map and limit this more | |
4145 | * precisly, but there's no way to get it safely under interrupt, | |
4146 | * so using TASK_SIZE as limit. | |
4147 | */ | |
4148 | static u64 perf_ustack_task_size(struct pt_regs *regs) | |
4149 | { | |
4150 | unsigned long addr = perf_user_stack_pointer(regs); | |
4151 | ||
4152 | if (!addr || addr >= TASK_SIZE) | |
4153 | return 0; | |
4154 | ||
4155 | return TASK_SIZE - addr; | |
4156 | } | |
4157 | ||
4158 | static u16 | |
4159 | perf_sample_ustack_size(u16 stack_size, u16 header_size, | |
4160 | struct pt_regs *regs) | |
4161 | { | |
4162 | u64 task_size; | |
4163 | ||
4164 | /* No regs, no stack pointer, no dump. */ | |
4165 | if (!regs) | |
4166 | return 0; | |
4167 | ||
4168 | /* | |
4169 | * Check if we fit in with the requested stack size into the: | |
4170 | * - TASK_SIZE | |
4171 | * If we don't, we limit the size to the TASK_SIZE. | |
4172 | * | |
4173 | * - remaining sample size | |
4174 | * If we don't, we customize the stack size to | |
4175 | * fit in to the remaining sample size. | |
4176 | */ | |
4177 | ||
4178 | task_size = min((u64) USHRT_MAX, perf_ustack_task_size(regs)); | |
4179 | stack_size = min(stack_size, (u16) task_size); | |
4180 | ||
4181 | /* Current header size plus static size and dynamic size. */ | |
4182 | header_size += 2 * sizeof(u64); | |
4183 | ||
4184 | /* Do we fit in with the current stack dump size? */ | |
4185 | if ((u16) (header_size + stack_size) < header_size) { | |
4186 | /* | |
4187 | * If we overflow the maximum size for the sample, | |
4188 | * we customize the stack dump size to fit in. | |
4189 | */ | |
4190 | stack_size = USHRT_MAX - header_size - sizeof(u64); | |
4191 | stack_size = round_up(stack_size, sizeof(u64)); | |
4192 | } | |
4193 | ||
4194 | return stack_size; | |
4195 | } | |
4196 | ||
4197 | static void | |
4198 | perf_output_sample_ustack(struct perf_output_handle *handle, u64 dump_size, | |
4199 | struct pt_regs *regs) | |
4200 | { | |
4201 | /* Case of a kernel thread, nothing to dump */ | |
4202 | if (!regs) { | |
4203 | u64 size = 0; | |
4204 | perf_output_put(handle, size); | |
4205 | } else { | |
4206 | unsigned long sp; | |
4207 | unsigned int rem; | |
4208 | u64 dyn_size; | |
4209 | ||
4210 | /* | |
4211 | * We dump: | |
4212 | * static size | |
4213 | * - the size requested by user or the best one we can fit | |
4214 | * in to the sample max size | |
4215 | * data | |
4216 | * - user stack dump data | |
4217 | * dynamic size | |
4218 | * - the actual dumped size | |
4219 | */ | |
4220 | ||
4221 | /* Static size. */ | |
4222 | perf_output_put(handle, dump_size); | |
4223 | ||
4224 | /* Data. */ | |
4225 | sp = perf_user_stack_pointer(regs); | |
4226 | rem = __output_copy_user(handle, (void *) sp, dump_size); | |
4227 | dyn_size = dump_size - rem; | |
4228 | ||
4229 | perf_output_skip(handle, rem); | |
4230 | ||
4231 | /* Dynamic size. */ | |
4232 | perf_output_put(handle, dyn_size); | |
4233 | } | |
4234 | } | |
4235 | ||
c980d109 ACM |
4236 | static void __perf_event_header__init_id(struct perf_event_header *header, |
4237 | struct perf_sample_data *data, | |
4238 | struct perf_event *event) | |
6844c09d ACM |
4239 | { |
4240 | u64 sample_type = event->attr.sample_type; | |
4241 | ||
4242 | data->type = sample_type; | |
4243 | header->size += event->id_header_size; | |
4244 | ||
4245 | if (sample_type & PERF_SAMPLE_TID) { | |
4246 | /* namespace issues */ | |
4247 | data->tid_entry.pid = perf_event_pid(event, current); | |
4248 | data->tid_entry.tid = perf_event_tid(event, current); | |
4249 | } | |
4250 | ||
4251 | if (sample_type & PERF_SAMPLE_TIME) | |
4252 | data->time = perf_clock(); | |
4253 | ||
4254 | if (sample_type & PERF_SAMPLE_ID) | |
4255 | data->id = primary_event_id(event); | |
4256 | ||
4257 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
4258 | data->stream_id = event->id; | |
4259 | ||
4260 | if (sample_type & PERF_SAMPLE_CPU) { | |
4261 | data->cpu_entry.cpu = raw_smp_processor_id(); | |
4262 | data->cpu_entry.reserved = 0; | |
4263 | } | |
4264 | } | |
4265 | ||
76369139 FW |
4266 | void perf_event_header__init_id(struct perf_event_header *header, |
4267 | struct perf_sample_data *data, | |
4268 | struct perf_event *event) | |
c980d109 ACM |
4269 | { |
4270 | if (event->attr.sample_id_all) | |
4271 | __perf_event_header__init_id(header, data, event); | |
4272 | } | |
4273 | ||
4274 | static void __perf_event__output_id_sample(struct perf_output_handle *handle, | |
4275 | struct perf_sample_data *data) | |
4276 | { | |
4277 | u64 sample_type = data->type; | |
4278 | ||
4279 | if (sample_type & PERF_SAMPLE_TID) | |
4280 | perf_output_put(handle, data->tid_entry); | |
4281 | ||
4282 | if (sample_type & PERF_SAMPLE_TIME) | |
4283 | perf_output_put(handle, data->time); | |
4284 | ||
4285 | if (sample_type & PERF_SAMPLE_ID) | |
4286 | perf_output_put(handle, data->id); | |
4287 | ||
4288 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
4289 | perf_output_put(handle, data->stream_id); | |
4290 | ||
4291 | if (sample_type & PERF_SAMPLE_CPU) | |
4292 | perf_output_put(handle, data->cpu_entry); | |
4293 | } | |
4294 | ||
76369139 FW |
4295 | void perf_event__output_id_sample(struct perf_event *event, |
4296 | struct perf_output_handle *handle, | |
4297 | struct perf_sample_data *sample) | |
c980d109 ACM |
4298 | { |
4299 | if (event->attr.sample_id_all) | |
4300 | __perf_event__output_id_sample(handle, sample); | |
4301 | } | |
4302 | ||
3dab77fb | 4303 | static void perf_output_read_one(struct perf_output_handle *handle, |
eed01528 SE |
4304 | struct perf_event *event, |
4305 | u64 enabled, u64 running) | |
3dab77fb | 4306 | { |
cdd6c482 | 4307 | u64 read_format = event->attr.read_format; |
3dab77fb PZ |
4308 | u64 values[4]; |
4309 | int n = 0; | |
4310 | ||
b5e58793 | 4311 | values[n++] = perf_event_count(event); |
3dab77fb | 4312 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { |
eed01528 | 4313 | values[n++] = enabled + |
cdd6c482 | 4314 | atomic64_read(&event->child_total_time_enabled); |
3dab77fb PZ |
4315 | } |
4316 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { | |
eed01528 | 4317 | values[n++] = running + |
cdd6c482 | 4318 | atomic64_read(&event->child_total_time_running); |
3dab77fb PZ |
4319 | } |
4320 | if (read_format & PERF_FORMAT_ID) | |
cdd6c482 | 4321 | values[n++] = primary_event_id(event); |
3dab77fb | 4322 | |
76369139 | 4323 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
4324 | } |
4325 | ||
4326 | /* | |
cdd6c482 | 4327 | * XXX PERF_FORMAT_GROUP vs inherited events seems difficult. |
3dab77fb PZ |
4328 | */ |
4329 | static void perf_output_read_group(struct perf_output_handle *handle, | |
eed01528 SE |
4330 | struct perf_event *event, |
4331 | u64 enabled, u64 running) | |
3dab77fb | 4332 | { |
cdd6c482 IM |
4333 | struct perf_event *leader = event->group_leader, *sub; |
4334 | u64 read_format = event->attr.read_format; | |
3dab77fb PZ |
4335 | u64 values[5]; |
4336 | int n = 0; | |
4337 | ||
4338 | values[n++] = 1 + leader->nr_siblings; | |
4339 | ||
4340 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
eed01528 | 4341 | values[n++] = enabled; |
3dab77fb PZ |
4342 | |
4343 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
eed01528 | 4344 | values[n++] = running; |
3dab77fb | 4345 | |
cdd6c482 | 4346 | if (leader != event) |
3dab77fb PZ |
4347 | leader->pmu->read(leader); |
4348 | ||
b5e58793 | 4349 | values[n++] = perf_event_count(leader); |
3dab77fb | 4350 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 4351 | values[n++] = primary_event_id(leader); |
3dab77fb | 4352 | |
76369139 | 4353 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb | 4354 | |
65abc865 | 4355 | list_for_each_entry(sub, &leader->sibling_list, group_entry) { |
3dab77fb PZ |
4356 | n = 0; |
4357 | ||
cdd6c482 | 4358 | if (sub != event) |
3dab77fb PZ |
4359 | sub->pmu->read(sub); |
4360 | ||
b5e58793 | 4361 | values[n++] = perf_event_count(sub); |
3dab77fb | 4362 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 4363 | values[n++] = primary_event_id(sub); |
3dab77fb | 4364 | |
76369139 | 4365 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
4366 | } |
4367 | } | |
4368 | ||
eed01528 SE |
4369 | #define PERF_FORMAT_TOTAL_TIMES (PERF_FORMAT_TOTAL_TIME_ENABLED|\ |
4370 | PERF_FORMAT_TOTAL_TIME_RUNNING) | |
4371 | ||
3dab77fb | 4372 | static void perf_output_read(struct perf_output_handle *handle, |
cdd6c482 | 4373 | struct perf_event *event) |
3dab77fb | 4374 | { |
e3f3541c | 4375 | u64 enabled = 0, running = 0, now; |
eed01528 SE |
4376 | u64 read_format = event->attr.read_format; |
4377 | ||
4378 | /* | |
4379 | * compute total_time_enabled, total_time_running | |
4380 | * based on snapshot values taken when the event | |
4381 | * was last scheduled in. | |
4382 | * | |
4383 | * we cannot simply called update_context_time() | |
4384 | * because of locking issue as we are called in | |
4385 | * NMI context | |
4386 | */ | |
c4794295 | 4387 | if (read_format & PERF_FORMAT_TOTAL_TIMES) |
e3f3541c | 4388 | calc_timer_values(event, &now, &enabled, &running); |
eed01528 | 4389 | |
cdd6c482 | 4390 | if (event->attr.read_format & PERF_FORMAT_GROUP) |
eed01528 | 4391 | perf_output_read_group(handle, event, enabled, running); |
3dab77fb | 4392 | else |
eed01528 | 4393 | perf_output_read_one(handle, event, enabled, running); |
3dab77fb PZ |
4394 | } |
4395 | ||
5622f295 MM |
4396 | void perf_output_sample(struct perf_output_handle *handle, |
4397 | struct perf_event_header *header, | |
4398 | struct perf_sample_data *data, | |
cdd6c482 | 4399 | struct perf_event *event) |
5622f295 MM |
4400 | { |
4401 | u64 sample_type = data->type; | |
4402 | ||
4403 | perf_output_put(handle, *header); | |
4404 | ||
4405 | if (sample_type & PERF_SAMPLE_IP) | |
4406 | perf_output_put(handle, data->ip); | |
4407 | ||
4408 | if (sample_type & PERF_SAMPLE_TID) | |
4409 | perf_output_put(handle, data->tid_entry); | |
4410 | ||
4411 | if (sample_type & PERF_SAMPLE_TIME) | |
4412 | perf_output_put(handle, data->time); | |
4413 | ||
4414 | if (sample_type & PERF_SAMPLE_ADDR) | |
4415 | perf_output_put(handle, data->addr); | |
4416 | ||
4417 | if (sample_type & PERF_SAMPLE_ID) | |
4418 | perf_output_put(handle, data->id); | |
4419 | ||
4420 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
4421 | perf_output_put(handle, data->stream_id); | |
4422 | ||
4423 | if (sample_type & PERF_SAMPLE_CPU) | |
4424 | perf_output_put(handle, data->cpu_entry); | |
4425 | ||
4426 | if (sample_type & PERF_SAMPLE_PERIOD) | |
4427 | perf_output_put(handle, data->period); | |
4428 | ||
4429 | if (sample_type & PERF_SAMPLE_READ) | |
cdd6c482 | 4430 | perf_output_read(handle, event); |
5622f295 MM |
4431 | |
4432 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { | |
4433 | if (data->callchain) { | |
4434 | int size = 1; | |
4435 | ||
4436 | if (data->callchain) | |
4437 | size += data->callchain->nr; | |
4438 | ||
4439 | size *= sizeof(u64); | |
4440 | ||
76369139 | 4441 | __output_copy(handle, data->callchain, size); |
5622f295 MM |
4442 | } else { |
4443 | u64 nr = 0; | |
4444 | perf_output_put(handle, nr); | |
4445 | } | |
4446 | } | |
4447 | ||
4448 | if (sample_type & PERF_SAMPLE_RAW) { | |
4449 | if (data->raw) { | |
4450 | perf_output_put(handle, data->raw->size); | |
76369139 FW |
4451 | __output_copy(handle, data->raw->data, |
4452 | data->raw->size); | |
5622f295 MM |
4453 | } else { |
4454 | struct { | |
4455 | u32 size; | |
4456 | u32 data; | |
4457 | } raw = { | |
4458 | .size = sizeof(u32), | |
4459 | .data = 0, | |
4460 | }; | |
4461 | perf_output_put(handle, raw); | |
4462 | } | |
4463 | } | |
a7ac67ea PZ |
4464 | |
4465 | if (!event->attr.watermark) { | |
4466 | int wakeup_events = event->attr.wakeup_events; | |
4467 | ||
4468 | if (wakeup_events) { | |
4469 | struct ring_buffer *rb = handle->rb; | |
4470 | int events = local_inc_return(&rb->events); | |
4471 | ||
4472 | if (events >= wakeup_events) { | |
4473 | local_sub(wakeup_events, &rb->events); | |
4474 | local_inc(&rb->wakeup); | |
4475 | } | |
4476 | } | |
4477 | } | |
bce38cd5 SE |
4478 | |
4479 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { | |
4480 | if (data->br_stack) { | |
4481 | size_t size; | |
4482 | ||
4483 | size = data->br_stack->nr | |
4484 | * sizeof(struct perf_branch_entry); | |
4485 | ||
4486 | perf_output_put(handle, data->br_stack->nr); | |
4487 | perf_output_copy(handle, data->br_stack->entries, size); | |
4488 | } else { | |
4489 | /* | |
4490 | * we always store at least the value of nr | |
4491 | */ | |
4492 | u64 nr = 0; | |
4493 | perf_output_put(handle, nr); | |
4494 | } | |
4495 | } | |
4018994f JO |
4496 | |
4497 | if (sample_type & PERF_SAMPLE_REGS_USER) { | |
4498 | u64 abi = data->regs_user.abi; | |
4499 | ||
4500 | /* | |
4501 | * If there are no regs to dump, notice it through | |
4502 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
4503 | */ | |
4504 | perf_output_put(handle, abi); | |
4505 | ||
4506 | if (abi) { | |
4507 | u64 mask = event->attr.sample_regs_user; | |
4508 | perf_output_sample_regs(handle, | |
4509 | data->regs_user.regs, | |
4510 | mask); | |
4511 | } | |
4512 | } | |
c5ebcedb JO |
4513 | |
4514 | if (sample_type & PERF_SAMPLE_STACK_USER) | |
4515 | perf_output_sample_ustack(handle, | |
4516 | data->stack_user_size, | |
4517 | data->regs_user.regs); | |
c3feedf2 AK |
4518 | |
4519 | if (sample_type & PERF_SAMPLE_WEIGHT) | |
4520 | perf_output_put(handle, data->weight); | |
d6be9ad6 SE |
4521 | |
4522 | if (sample_type & PERF_SAMPLE_DATA_SRC) | |
4523 | perf_output_put(handle, data->data_src.val); | |
5622f295 MM |
4524 | } |
4525 | ||
4526 | void perf_prepare_sample(struct perf_event_header *header, | |
4527 | struct perf_sample_data *data, | |
cdd6c482 | 4528 | struct perf_event *event, |
5622f295 | 4529 | struct pt_regs *regs) |
7b732a75 | 4530 | { |
cdd6c482 | 4531 | u64 sample_type = event->attr.sample_type; |
7b732a75 | 4532 | |
cdd6c482 | 4533 | header->type = PERF_RECORD_SAMPLE; |
c320c7b7 | 4534 | header->size = sizeof(*header) + event->header_size; |
5622f295 MM |
4535 | |
4536 | header->misc = 0; | |
4537 | header->misc |= perf_misc_flags(regs); | |
6fab0192 | 4538 | |
c980d109 | 4539 | __perf_event_header__init_id(header, data, event); |
6844c09d | 4540 | |
c320c7b7 | 4541 | if (sample_type & PERF_SAMPLE_IP) |
5622f295 MM |
4542 | data->ip = perf_instruction_pointer(regs); |
4543 | ||
b23f3325 | 4544 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { |
5622f295 | 4545 | int size = 1; |
394ee076 | 4546 | |
e6dab5ff | 4547 | data->callchain = perf_callchain(event, regs); |
5622f295 MM |
4548 | |
4549 | if (data->callchain) | |
4550 | size += data->callchain->nr; | |
4551 | ||
4552 | header->size += size * sizeof(u64); | |
394ee076 PZ |
4553 | } |
4554 | ||
3a43ce68 | 4555 | if (sample_type & PERF_SAMPLE_RAW) { |
a044560c PZ |
4556 | int size = sizeof(u32); |
4557 | ||
4558 | if (data->raw) | |
4559 | size += data->raw->size; | |
4560 | else | |
4561 | size += sizeof(u32); | |
4562 | ||
4563 | WARN_ON_ONCE(size & (sizeof(u64)-1)); | |
5622f295 | 4564 | header->size += size; |
7f453c24 | 4565 | } |
bce38cd5 SE |
4566 | |
4567 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { | |
4568 | int size = sizeof(u64); /* nr */ | |
4569 | if (data->br_stack) { | |
4570 | size += data->br_stack->nr | |
4571 | * sizeof(struct perf_branch_entry); | |
4572 | } | |
4573 | header->size += size; | |
4574 | } | |
4018994f JO |
4575 | |
4576 | if (sample_type & PERF_SAMPLE_REGS_USER) { | |
4577 | /* regs dump ABI info */ | |
4578 | int size = sizeof(u64); | |
4579 | ||
4580 | perf_sample_regs_user(&data->regs_user, regs); | |
4581 | ||
4582 | if (data->regs_user.regs) { | |
4583 | u64 mask = event->attr.sample_regs_user; | |
4584 | size += hweight64(mask) * sizeof(u64); | |
4585 | } | |
4586 | ||
4587 | header->size += size; | |
4588 | } | |
c5ebcedb JO |
4589 | |
4590 | if (sample_type & PERF_SAMPLE_STACK_USER) { | |
4591 | /* | |
4592 | * Either we need PERF_SAMPLE_STACK_USER bit to be allways | |
4593 | * processed as the last one or have additional check added | |
4594 | * in case new sample type is added, because we could eat | |
4595 | * up the rest of the sample size. | |
4596 | */ | |
4597 | struct perf_regs_user *uregs = &data->regs_user; | |
4598 | u16 stack_size = event->attr.sample_stack_user; | |
4599 | u16 size = sizeof(u64); | |
4600 | ||
4601 | if (!uregs->abi) | |
4602 | perf_sample_regs_user(uregs, regs); | |
4603 | ||
4604 | stack_size = perf_sample_ustack_size(stack_size, header->size, | |
4605 | uregs->regs); | |
4606 | ||
4607 | /* | |
4608 | * If there is something to dump, add space for the dump | |
4609 | * itself and for the field that tells the dynamic size, | |
4610 | * which is how many have been actually dumped. | |
4611 | */ | |
4612 | if (stack_size) | |
4613 | size += sizeof(u64) + stack_size; | |
4614 | ||
4615 | data->stack_user_size = stack_size; | |
4616 | header->size += size; | |
4617 | } | |
5622f295 | 4618 | } |
7f453c24 | 4619 | |
a8b0ca17 | 4620 | static void perf_event_output(struct perf_event *event, |
5622f295 MM |
4621 | struct perf_sample_data *data, |
4622 | struct pt_regs *regs) | |
4623 | { | |
4624 | struct perf_output_handle handle; | |
4625 | struct perf_event_header header; | |
689802b2 | 4626 | |
927c7a9e FW |
4627 | /* protect the callchain buffers */ |
4628 | rcu_read_lock(); | |
4629 | ||
cdd6c482 | 4630 | perf_prepare_sample(&header, data, event, regs); |
5c148194 | 4631 | |
a7ac67ea | 4632 | if (perf_output_begin(&handle, event, header.size)) |
927c7a9e | 4633 | goto exit; |
0322cd6e | 4634 | |
cdd6c482 | 4635 | perf_output_sample(&handle, &header, data, event); |
f413cdb8 | 4636 | |
8a057d84 | 4637 | perf_output_end(&handle); |
927c7a9e FW |
4638 | |
4639 | exit: | |
4640 | rcu_read_unlock(); | |
0322cd6e PZ |
4641 | } |
4642 | ||
38b200d6 | 4643 | /* |
cdd6c482 | 4644 | * read event_id |
38b200d6 PZ |
4645 | */ |
4646 | ||
4647 | struct perf_read_event { | |
4648 | struct perf_event_header header; | |
4649 | ||
4650 | u32 pid; | |
4651 | u32 tid; | |
38b200d6 PZ |
4652 | }; |
4653 | ||
4654 | static void | |
cdd6c482 | 4655 | perf_event_read_event(struct perf_event *event, |
38b200d6 PZ |
4656 | struct task_struct *task) |
4657 | { | |
4658 | struct perf_output_handle handle; | |
c980d109 | 4659 | struct perf_sample_data sample; |
dfc65094 | 4660 | struct perf_read_event read_event = { |
38b200d6 | 4661 | .header = { |
cdd6c482 | 4662 | .type = PERF_RECORD_READ, |
38b200d6 | 4663 | .misc = 0, |
c320c7b7 | 4664 | .size = sizeof(read_event) + event->read_size, |
38b200d6 | 4665 | }, |
cdd6c482 IM |
4666 | .pid = perf_event_pid(event, task), |
4667 | .tid = perf_event_tid(event, task), | |
38b200d6 | 4668 | }; |
3dab77fb | 4669 | int ret; |
38b200d6 | 4670 | |
c980d109 | 4671 | perf_event_header__init_id(&read_event.header, &sample, event); |
a7ac67ea | 4672 | ret = perf_output_begin(&handle, event, read_event.header.size); |
38b200d6 PZ |
4673 | if (ret) |
4674 | return; | |
4675 | ||
dfc65094 | 4676 | perf_output_put(&handle, read_event); |
cdd6c482 | 4677 | perf_output_read(&handle, event); |
c980d109 | 4678 | perf_event__output_id_sample(event, &handle, &sample); |
3dab77fb | 4679 | |
38b200d6 PZ |
4680 | perf_output_end(&handle); |
4681 | } | |
4682 | ||
52d857a8 JO |
4683 | typedef void (perf_event_aux_output_cb)(struct perf_event *event, void *data); |
4684 | ||
4685 | static void | |
4686 | perf_event_aux_ctx(struct perf_event_context *ctx, | |
52d857a8 JO |
4687 | perf_event_aux_output_cb output, |
4688 | void *data) | |
4689 | { | |
4690 | struct perf_event *event; | |
4691 | ||
4692 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
4693 | if (event->state < PERF_EVENT_STATE_INACTIVE) | |
4694 | continue; | |
4695 | if (!event_filter_match(event)) | |
4696 | continue; | |
67516844 | 4697 | output(event, data); |
52d857a8 JO |
4698 | } |
4699 | } | |
4700 | ||
4701 | static void | |
67516844 | 4702 | perf_event_aux(perf_event_aux_output_cb output, void *data, |
52d857a8 JO |
4703 | struct perf_event_context *task_ctx) |
4704 | { | |
4705 | struct perf_cpu_context *cpuctx; | |
4706 | struct perf_event_context *ctx; | |
4707 | struct pmu *pmu; | |
4708 | int ctxn; | |
4709 | ||
4710 | rcu_read_lock(); | |
4711 | list_for_each_entry_rcu(pmu, &pmus, entry) { | |
4712 | cpuctx = get_cpu_ptr(pmu->pmu_cpu_context); | |
4713 | if (cpuctx->unique_pmu != pmu) | |
4714 | goto next; | |
67516844 | 4715 | perf_event_aux_ctx(&cpuctx->ctx, output, data); |
52d857a8 JO |
4716 | if (task_ctx) |
4717 | goto next; | |
4718 | ctxn = pmu->task_ctx_nr; | |
4719 | if (ctxn < 0) | |
4720 | goto next; | |
4721 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); | |
4722 | if (ctx) | |
67516844 | 4723 | perf_event_aux_ctx(ctx, output, data); |
52d857a8 JO |
4724 | next: |
4725 | put_cpu_ptr(pmu->pmu_cpu_context); | |
4726 | } | |
4727 | ||
4728 | if (task_ctx) { | |
4729 | preempt_disable(); | |
67516844 | 4730 | perf_event_aux_ctx(task_ctx, output, data); |
52d857a8 JO |
4731 | preempt_enable(); |
4732 | } | |
4733 | rcu_read_unlock(); | |
4734 | } | |
4735 | ||
60313ebe | 4736 | /* |
9f498cc5 PZ |
4737 | * task tracking -- fork/exit |
4738 | * | |
3af9e859 | 4739 | * enabled by: attr.comm | attr.mmap | attr.mmap_data | attr.task |
60313ebe PZ |
4740 | */ |
4741 | ||
9f498cc5 | 4742 | struct perf_task_event { |
3a80b4a3 | 4743 | struct task_struct *task; |
cdd6c482 | 4744 | struct perf_event_context *task_ctx; |
60313ebe PZ |
4745 | |
4746 | struct { | |
4747 | struct perf_event_header header; | |
4748 | ||
4749 | u32 pid; | |
4750 | u32 ppid; | |
9f498cc5 PZ |
4751 | u32 tid; |
4752 | u32 ptid; | |
393b2ad8 | 4753 | u64 time; |
cdd6c482 | 4754 | } event_id; |
60313ebe PZ |
4755 | }; |
4756 | ||
67516844 JO |
4757 | static int perf_event_task_match(struct perf_event *event) |
4758 | { | |
4759 | return event->attr.comm || event->attr.mmap || | |
4760 | event->attr.mmap_data || event->attr.task; | |
4761 | } | |
4762 | ||
cdd6c482 | 4763 | static void perf_event_task_output(struct perf_event *event, |
52d857a8 | 4764 | void *data) |
60313ebe | 4765 | { |
52d857a8 | 4766 | struct perf_task_event *task_event = data; |
60313ebe | 4767 | struct perf_output_handle handle; |
c980d109 | 4768 | struct perf_sample_data sample; |
9f498cc5 | 4769 | struct task_struct *task = task_event->task; |
c980d109 | 4770 | int ret, size = task_event->event_id.header.size; |
8bb39f9a | 4771 | |
67516844 JO |
4772 | if (!perf_event_task_match(event)) |
4773 | return; | |
4774 | ||
c980d109 | 4775 | perf_event_header__init_id(&task_event->event_id.header, &sample, event); |
60313ebe | 4776 | |
c980d109 | 4777 | ret = perf_output_begin(&handle, event, |
a7ac67ea | 4778 | task_event->event_id.header.size); |
ef60777c | 4779 | if (ret) |
c980d109 | 4780 | goto out; |
60313ebe | 4781 | |
cdd6c482 IM |
4782 | task_event->event_id.pid = perf_event_pid(event, task); |
4783 | task_event->event_id.ppid = perf_event_pid(event, current); | |
60313ebe | 4784 | |
cdd6c482 IM |
4785 | task_event->event_id.tid = perf_event_tid(event, task); |
4786 | task_event->event_id.ptid = perf_event_tid(event, current); | |
9f498cc5 | 4787 | |
cdd6c482 | 4788 | perf_output_put(&handle, task_event->event_id); |
393b2ad8 | 4789 | |
c980d109 ACM |
4790 | perf_event__output_id_sample(event, &handle, &sample); |
4791 | ||
60313ebe | 4792 | perf_output_end(&handle); |
c980d109 ACM |
4793 | out: |
4794 | task_event->event_id.header.size = size; | |
60313ebe PZ |
4795 | } |
4796 | ||
cdd6c482 IM |
4797 | static void perf_event_task(struct task_struct *task, |
4798 | struct perf_event_context *task_ctx, | |
3a80b4a3 | 4799 | int new) |
60313ebe | 4800 | { |
9f498cc5 | 4801 | struct perf_task_event task_event; |
60313ebe | 4802 | |
cdd6c482 IM |
4803 | if (!atomic_read(&nr_comm_events) && |
4804 | !atomic_read(&nr_mmap_events) && | |
4805 | !atomic_read(&nr_task_events)) | |
60313ebe PZ |
4806 | return; |
4807 | ||
9f498cc5 | 4808 | task_event = (struct perf_task_event){ |
3a80b4a3 PZ |
4809 | .task = task, |
4810 | .task_ctx = task_ctx, | |
cdd6c482 | 4811 | .event_id = { |
60313ebe | 4812 | .header = { |
cdd6c482 | 4813 | .type = new ? PERF_RECORD_FORK : PERF_RECORD_EXIT, |
573402db | 4814 | .misc = 0, |
cdd6c482 | 4815 | .size = sizeof(task_event.event_id), |
60313ebe | 4816 | }, |
573402db PZ |
4817 | /* .pid */ |
4818 | /* .ppid */ | |
9f498cc5 PZ |
4819 | /* .tid */ |
4820 | /* .ptid */ | |
6f93d0a7 | 4821 | .time = perf_clock(), |
60313ebe PZ |
4822 | }, |
4823 | }; | |
4824 | ||
67516844 | 4825 | perf_event_aux(perf_event_task_output, |
52d857a8 JO |
4826 | &task_event, |
4827 | task_ctx); | |
9f498cc5 PZ |
4828 | } |
4829 | ||
cdd6c482 | 4830 | void perf_event_fork(struct task_struct *task) |
9f498cc5 | 4831 | { |
cdd6c482 | 4832 | perf_event_task(task, NULL, 1); |
60313ebe PZ |
4833 | } |
4834 | ||
8d1b2d93 PZ |
4835 | /* |
4836 | * comm tracking | |
4837 | */ | |
4838 | ||
4839 | struct perf_comm_event { | |
22a4f650 IM |
4840 | struct task_struct *task; |
4841 | char *comm; | |
8d1b2d93 PZ |
4842 | int comm_size; |
4843 | ||
4844 | struct { | |
4845 | struct perf_event_header header; | |
4846 | ||
4847 | u32 pid; | |
4848 | u32 tid; | |
cdd6c482 | 4849 | } event_id; |
8d1b2d93 PZ |
4850 | }; |
4851 | ||
67516844 JO |
4852 | static int perf_event_comm_match(struct perf_event *event) |
4853 | { | |
4854 | return event->attr.comm; | |
4855 | } | |
4856 | ||
cdd6c482 | 4857 | static void perf_event_comm_output(struct perf_event *event, |
52d857a8 | 4858 | void *data) |
8d1b2d93 | 4859 | { |
52d857a8 | 4860 | struct perf_comm_event *comm_event = data; |
8d1b2d93 | 4861 | struct perf_output_handle handle; |
c980d109 | 4862 | struct perf_sample_data sample; |
cdd6c482 | 4863 | int size = comm_event->event_id.header.size; |
c980d109 ACM |
4864 | int ret; |
4865 | ||
67516844 JO |
4866 | if (!perf_event_comm_match(event)) |
4867 | return; | |
4868 | ||
c980d109 ACM |
4869 | perf_event_header__init_id(&comm_event->event_id.header, &sample, event); |
4870 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 4871 | comm_event->event_id.header.size); |
8d1b2d93 PZ |
4872 | |
4873 | if (ret) | |
c980d109 | 4874 | goto out; |
8d1b2d93 | 4875 | |
cdd6c482 IM |
4876 | comm_event->event_id.pid = perf_event_pid(event, comm_event->task); |
4877 | comm_event->event_id.tid = perf_event_tid(event, comm_event->task); | |
709e50cf | 4878 | |
cdd6c482 | 4879 | perf_output_put(&handle, comm_event->event_id); |
76369139 | 4880 | __output_copy(&handle, comm_event->comm, |
8d1b2d93 | 4881 | comm_event->comm_size); |
c980d109 ACM |
4882 | |
4883 | perf_event__output_id_sample(event, &handle, &sample); | |
4884 | ||
8d1b2d93 | 4885 | perf_output_end(&handle); |
c980d109 ACM |
4886 | out: |
4887 | comm_event->event_id.header.size = size; | |
8d1b2d93 PZ |
4888 | } |
4889 | ||
cdd6c482 | 4890 | static void perf_event_comm_event(struct perf_comm_event *comm_event) |
8d1b2d93 | 4891 | { |
413ee3b4 | 4892 | char comm[TASK_COMM_LEN]; |
8d1b2d93 | 4893 | unsigned int size; |
8d1b2d93 | 4894 | |
413ee3b4 | 4895 | memset(comm, 0, sizeof(comm)); |
96b02d78 | 4896 | strlcpy(comm, comm_event->task->comm, sizeof(comm)); |
888fcee0 | 4897 | size = ALIGN(strlen(comm)+1, sizeof(u64)); |
8d1b2d93 PZ |
4898 | |
4899 | comm_event->comm = comm; | |
4900 | comm_event->comm_size = size; | |
4901 | ||
cdd6c482 | 4902 | comm_event->event_id.header.size = sizeof(comm_event->event_id) + size; |
8dc85d54 | 4903 | |
67516844 | 4904 | perf_event_aux(perf_event_comm_output, |
52d857a8 JO |
4905 | comm_event, |
4906 | NULL); | |
8d1b2d93 PZ |
4907 | } |
4908 | ||
cdd6c482 | 4909 | void perf_event_comm(struct task_struct *task) |
8d1b2d93 | 4910 | { |
9ee318a7 | 4911 | struct perf_comm_event comm_event; |
8dc85d54 PZ |
4912 | struct perf_event_context *ctx; |
4913 | int ctxn; | |
9ee318a7 | 4914 | |
c79aa0d9 | 4915 | rcu_read_lock(); |
8dc85d54 PZ |
4916 | for_each_task_context_nr(ctxn) { |
4917 | ctx = task->perf_event_ctxp[ctxn]; | |
4918 | if (!ctx) | |
4919 | continue; | |
9ee318a7 | 4920 | |
8dc85d54 PZ |
4921 | perf_event_enable_on_exec(ctx); |
4922 | } | |
c79aa0d9 | 4923 | rcu_read_unlock(); |
9ee318a7 | 4924 | |
cdd6c482 | 4925 | if (!atomic_read(&nr_comm_events)) |
9ee318a7 | 4926 | return; |
a63eaf34 | 4927 | |
9ee318a7 | 4928 | comm_event = (struct perf_comm_event){ |
8d1b2d93 | 4929 | .task = task, |
573402db PZ |
4930 | /* .comm */ |
4931 | /* .comm_size */ | |
cdd6c482 | 4932 | .event_id = { |
573402db | 4933 | .header = { |
cdd6c482 | 4934 | .type = PERF_RECORD_COMM, |
573402db PZ |
4935 | .misc = 0, |
4936 | /* .size */ | |
4937 | }, | |
4938 | /* .pid */ | |
4939 | /* .tid */ | |
8d1b2d93 PZ |
4940 | }, |
4941 | }; | |
4942 | ||
cdd6c482 | 4943 | perf_event_comm_event(&comm_event); |
8d1b2d93 PZ |
4944 | } |
4945 | ||
0a4a9391 PZ |
4946 | /* |
4947 | * mmap tracking | |
4948 | */ | |
4949 | ||
4950 | struct perf_mmap_event { | |
089dd79d PZ |
4951 | struct vm_area_struct *vma; |
4952 | ||
4953 | const char *file_name; | |
4954 | int file_size; | |
0a4a9391 PZ |
4955 | |
4956 | struct { | |
4957 | struct perf_event_header header; | |
4958 | ||
4959 | u32 pid; | |
4960 | u32 tid; | |
4961 | u64 start; | |
4962 | u64 len; | |
4963 | u64 pgoff; | |
cdd6c482 | 4964 | } event_id; |
0a4a9391 PZ |
4965 | }; |
4966 | ||
67516844 JO |
4967 | static int perf_event_mmap_match(struct perf_event *event, |
4968 | void *data) | |
4969 | { | |
4970 | struct perf_mmap_event *mmap_event = data; | |
4971 | struct vm_area_struct *vma = mmap_event->vma; | |
4972 | int executable = vma->vm_flags & VM_EXEC; | |
4973 | ||
4974 | return (!executable && event->attr.mmap_data) || | |
4975 | (executable && event->attr.mmap); | |
4976 | } | |
4977 | ||
cdd6c482 | 4978 | static void perf_event_mmap_output(struct perf_event *event, |
52d857a8 | 4979 | void *data) |
0a4a9391 | 4980 | { |
52d857a8 | 4981 | struct perf_mmap_event *mmap_event = data; |
0a4a9391 | 4982 | struct perf_output_handle handle; |
c980d109 | 4983 | struct perf_sample_data sample; |
cdd6c482 | 4984 | int size = mmap_event->event_id.header.size; |
c980d109 | 4985 | int ret; |
0a4a9391 | 4986 | |
67516844 JO |
4987 | if (!perf_event_mmap_match(event, data)) |
4988 | return; | |
4989 | ||
c980d109 ACM |
4990 | perf_event_header__init_id(&mmap_event->event_id.header, &sample, event); |
4991 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 4992 | mmap_event->event_id.header.size); |
0a4a9391 | 4993 | if (ret) |
c980d109 | 4994 | goto out; |
0a4a9391 | 4995 | |
cdd6c482 IM |
4996 | mmap_event->event_id.pid = perf_event_pid(event, current); |
4997 | mmap_event->event_id.tid = perf_event_tid(event, current); | |
709e50cf | 4998 | |
cdd6c482 | 4999 | perf_output_put(&handle, mmap_event->event_id); |
76369139 | 5000 | __output_copy(&handle, mmap_event->file_name, |
0a4a9391 | 5001 | mmap_event->file_size); |
c980d109 ACM |
5002 | |
5003 | perf_event__output_id_sample(event, &handle, &sample); | |
5004 | ||
78d613eb | 5005 | perf_output_end(&handle); |
c980d109 ACM |
5006 | out: |
5007 | mmap_event->event_id.header.size = size; | |
0a4a9391 PZ |
5008 | } |
5009 | ||
cdd6c482 | 5010 | static void perf_event_mmap_event(struct perf_mmap_event *mmap_event) |
0a4a9391 | 5011 | { |
089dd79d PZ |
5012 | struct vm_area_struct *vma = mmap_event->vma; |
5013 | struct file *file = vma->vm_file; | |
0a4a9391 PZ |
5014 | unsigned int size; |
5015 | char tmp[16]; | |
5016 | char *buf = NULL; | |
089dd79d | 5017 | const char *name; |
0a4a9391 | 5018 | |
413ee3b4 AB |
5019 | memset(tmp, 0, sizeof(tmp)); |
5020 | ||
0a4a9391 | 5021 | if (file) { |
413ee3b4 | 5022 | /* |
76369139 | 5023 | * d_path works from the end of the rb backwards, so we |
413ee3b4 AB |
5024 | * need to add enough zero bytes after the string to handle |
5025 | * the 64bit alignment we do later. | |
5026 | */ | |
5027 | buf = kzalloc(PATH_MAX + sizeof(u64), GFP_KERNEL); | |
0a4a9391 PZ |
5028 | if (!buf) { |
5029 | name = strncpy(tmp, "//enomem", sizeof(tmp)); | |
5030 | goto got_name; | |
5031 | } | |
d3d21c41 | 5032 | name = d_path(&file->f_path, buf, PATH_MAX); |
0a4a9391 PZ |
5033 | if (IS_ERR(name)) { |
5034 | name = strncpy(tmp, "//toolong", sizeof(tmp)); | |
5035 | goto got_name; | |
5036 | } | |
5037 | } else { | |
413ee3b4 AB |
5038 | if (arch_vma_name(mmap_event->vma)) { |
5039 | name = strncpy(tmp, arch_vma_name(mmap_event->vma), | |
c97847d2 CG |
5040 | sizeof(tmp) - 1); |
5041 | tmp[sizeof(tmp) - 1] = '\0'; | |
089dd79d | 5042 | goto got_name; |
413ee3b4 | 5043 | } |
089dd79d PZ |
5044 | |
5045 | if (!vma->vm_mm) { | |
5046 | name = strncpy(tmp, "[vdso]", sizeof(tmp)); | |
5047 | goto got_name; | |
3af9e859 EM |
5048 | } else if (vma->vm_start <= vma->vm_mm->start_brk && |
5049 | vma->vm_end >= vma->vm_mm->brk) { | |
5050 | name = strncpy(tmp, "[heap]", sizeof(tmp)); | |
5051 | goto got_name; | |
5052 | } else if (vma->vm_start <= vma->vm_mm->start_stack && | |
5053 | vma->vm_end >= vma->vm_mm->start_stack) { | |
5054 | name = strncpy(tmp, "[stack]", sizeof(tmp)); | |
5055 | goto got_name; | |
089dd79d PZ |
5056 | } |
5057 | ||
0a4a9391 PZ |
5058 | name = strncpy(tmp, "//anon", sizeof(tmp)); |
5059 | goto got_name; | |
5060 | } | |
5061 | ||
5062 | got_name: | |
888fcee0 | 5063 | size = ALIGN(strlen(name)+1, sizeof(u64)); |
0a4a9391 PZ |
5064 | |
5065 | mmap_event->file_name = name; | |
5066 | mmap_event->file_size = size; | |
5067 | ||
2fe85427 SE |
5068 | if (!(vma->vm_flags & VM_EXEC)) |
5069 | mmap_event->event_id.header.misc |= PERF_RECORD_MISC_MMAP_DATA; | |
5070 | ||
cdd6c482 | 5071 | mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size; |
0a4a9391 | 5072 | |
67516844 | 5073 | perf_event_aux(perf_event_mmap_output, |
52d857a8 JO |
5074 | mmap_event, |
5075 | NULL); | |
665c2142 | 5076 | |
0a4a9391 PZ |
5077 | kfree(buf); |
5078 | } | |
5079 | ||
3af9e859 | 5080 | void perf_event_mmap(struct vm_area_struct *vma) |
0a4a9391 | 5081 | { |
9ee318a7 PZ |
5082 | struct perf_mmap_event mmap_event; |
5083 | ||
cdd6c482 | 5084 | if (!atomic_read(&nr_mmap_events)) |
9ee318a7 PZ |
5085 | return; |
5086 | ||
5087 | mmap_event = (struct perf_mmap_event){ | |
089dd79d | 5088 | .vma = vma, |
573402db PZ |
5089 | /* .file_name */ |
5090 | /* .file_size */ | |
cdd6c482 | 5091 | .event_id = { |
573402db | 5092 | .header = { |
cdd6c482 | 5093 | .type = PERF_RECORD_MMAP, |
39447b38 | 5094 | .misc = PERF_RECORD_MISC_USER, |
573402db PZ |
5095 | /* .size */ |
5096 | }, | |
5097 | /* .pid */ | |
5098 | /* .tid */ | |
089dd79d PZ |
5099 | .start = vma->vm_start, |
5100 | .len = vma->vm_end - vma->vm_start, | |
3a0304e9 | 5101 | .pgoff = (u64)vma->vm_pgoff << PAGE_SHIFT, |
0a4a9391 PZ |
5102 | }, |
5103 | }; | |
5104 | ||
cdd6c482 | 5105 | perf_event_mmap_event(&mmap_event); |
0a4a9391 PZ |
5106 | } |
5107 | ||
a78ac325 PZ |
5108 | /* |
5109 | * IRQ throttle logging | |
5110 | */ | |
5111 | ||
cdd6c482 | 5112 | static void perf_log_throttle(struct perf_event *event, int enable) |
a78ac325 PZ |
5113 | { |
5114 | struct perf_output_handle handle; | |
c980d109 | 5115 | struct perf_sample_data sample; |
a78ac325 PZ |
5116 | int ret; |
5117 | ||
5118 | struct { | |
5119 | struct perf_event_header header; | |
5120 | u64 time; | |
cca3f454 | 5121 | u64 id; |
7f453c24 | 5122 | u64 stream_id; |
a78ac325 PZ |
5123 | } throttle_event = { |
5124 | .header = { | |
cdd6c482 | 5125 | .type = PERF_RECORD_THROTTLE, |
a78ac325 PZ |
5126 | .misc = 0, |
5127 | .size = sizeof(throttle_event), | |
5128 | }, | |
def0a9b2 | 5129 | .time = perf_clock(), |
cdd6c482 IM |
5130 | .id = primary_event_id(event), |
5131 | .stream_id = event->id, | |
a78ac325 PZ |
5132 | }; |
5133 | ||
966ee4d6 | 5134 | if (enable) |
cdd6c482 | 5135 | throttle_event.header.type = PERF_RECORD_UNTHROTTLE; |
966ee4d6 | 5136 | |
c980d109 ACM |
5137 | perf_event_header__init_id(&throttle_event.header, &sample, event); |
5138 | ||
5139 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 5140 | throttle_event.header.size); |
a78ac325 PZ |
5141 | if (ret) |
5142 | return; | |
5143 | ||
5144 | perf_output_put(&handle, throttle_event); | |
c980d109 | 5145 | perf_event__output_id_sample(event, &handle, &sample); |
a78ac325 PZ |
5146 | perf_output_end(&handle); |
5147 | } | |
5148 | ||
f6c7d5fe | 5149 | /* |
cdd6c482 | 5150 | * Generic event overflow handling, sampling. |
f6c7d5fe PZ |
5151 | */ |
5152 | ||
a8b0ca17 | 5153 | static int __perf_event_overflow(struct perf_event *event, |
5622f295 MM |
5154 | int throttle, struct perf_sample_data *data, |
5155 | struct pt_regs *regs) | |
f6c7d5fe | 5156 | { |
cdd6c482 IM |
5157 | int events = atomic_read(&event->event_limit); |
5158 | struct hw_perf_event *hwc = &event->hw; | |
e050e3f0 | 5159 | u64 seq; |
79f14641 PZ |
5160 | int ret = 0; |
5161 | ||
96398826 PZ |
5162 | /* |
5163 | * Non-sampling counters might still use the PMI to fold short | |
5164 | * hardware counters, ignore those. | |
5165 | */ | |
5166 | if (unlikely(!is_sampling_event(event))) | |
5167 | return 0; | |
5168 | ||
e050e3f0 SE |
5169 | seq = __this_cpu_read(perf_throttled_seq); |
5170 | if (seq != hwc->interrupts_seq) { | |
5171 | hwc->interrupts_seq = seq; | |
5172 | hwc->interrupts = 1; | |
5173 | } else { | |
5174 | hwc->interrupts++; | |
5175 | if (unlikely(throttle | |
5176 | && hwc->interrupts >= max_samples_per_tick)) { | |
5177 | __this_cpu_inc(perf_throttled_count); | |
163ec435 PZ |
5178 | hwc->interrupts = MAX_INTERRUPTS; |
5179 | perf_log_throttle(event, 0); | |
a78ac325 PZ |
5180 | ret = 1; |
5181 | } | |
e050e3f0 | 5182 | } |
60db5e09 | 5183 | |
cdd6c482 | 5184 | if (event->attr.freq) { |
def0a9b2 | 5185 | u64 now = perf_clock(); |
abd50713 | 5186 | s64 delta = now - hwc->freq_time_stamp; |
bd2b5b12 | 5187 | |
abd50713 | 5188 | hwc->freq_time_stamp = now; |
bd2b5b12 | 5189 | |
abd50713 | 5190 | if (delta > 0 && delta < 2*TICK_NSEC) |
f39d47ff | 5191 | perf_adjust_period(event, delta, hwc->last_period, true); |
bd2b5b12 PZ |
5192 | } |
5193 | ||
2023b359 PZ |
5194 | /* |
5195 | * XXX event_limit might not quite work as expected on inherited | |
cdd6c482 | 5196 | * events |
2023b359 PZ |
5197 | */ |
5198 | ||
cdd6c482 IM |
5199 | event->pending_kill = POLL_IN; |
5200 | if (events && atomic_dec_and_test(&event->event_limit)) { | |
79f14641 | 5201 | ret = 1; |
cdd6c482 | 5202 | event->pending_kill = POLL_HUP; |
a8b0ca17 PZ |
5203 | event->pending_disable = 1; |
5204 | irq_work_queue(&event->pending); | |
79f14641 PZ |
5205 | } |
5206 | ||
453f19ee | 5207 | if (event->overflow_handler) |
a8b0ca17 | 5208 | event->overflow_handler(event, data, regs); |
453f19ee | 5209 | else |
a8b0ca17 | 5210 | perf_event_output(event, data, regs); |
453f19ee | 5211 | |
f506b3dc | 5212 | if (event->fasync && event->pending_kill) { |
a8b0ca17 PZ |
5213 | event->pending_wakeup = 1; |
5214 | irq_work_queue(&event->pending); | |
f506b3dc PZ |
5215 | } |
5216 | ||
79f14641 | 5217 | return ret; |
f6c7d5fe PZ |
5218 | } |
5219 | ||
a8b0ca17 | 5220 | int perf_event_overflow(struct perf_event *event, |
5622f295 MM |
5221 | struct perf_sample_data *data, |
5222 | struct pt_regs *regs) | |
850bc73f | 5223 | { |
a8b0ca17 | 5224 | return __perf_event_overflow(event, 1, data, regs); |
850bc73f PZ |
5225 | } |
5226 | ||
15dbf27c | 5227 | /* |
cdd6c482 | 5228 | * Generic software event infrastructure |
15dbf27c PZ |
5229 | */ |
5230 | ||
b28ab83c PZ |
5231 | struct swevent_htable { |
5232 | struct swevent_hlist *swevent_hlist; | |
5233 | struct mutex hlist_mutex; | |
5234 | int hlist_refcount; | |
5235 | ||
5236 | /* Recursion avoidance in each contexts */ | |
5237 | int recursion[PERF_NR_CONTEXTS]; | |
5238 | }; | |
5239 | ||
5240 | static DEFINE_PER_CPU(struct swevent_htable, swevent_htable); | |
5241 | ||
7b4b6658 | 5242 | /* |
cdd6c482 IM |
5243 | * We directly increment event->count and keep a second value in |
5244 | * event->hw.period_left to count intervals. This period event | |
7b4b6658 PZ |
5245 | * is kept in the range [-sample_period, 0] so that we can use the |
5246 | * sign as trigger. | |
5247 | */ | |
5248 | ||
ab573844 | 5249 | u64 perf_swevent_set_period(struct perf_event *event) |
15dbf27c | 5250 | { |
cdd6c482 | 5251 | struct hw_perf_event *hwc = &event->hw; |
7b4b6658 PZ |
5252 | u64 period = hwc->last_period; |
5253 | u64 nr, offset; | |
5254 | s64 old, val; | |
5255 | ||
5256 | hwc->last_period = hwc->sample_period; | |
15dbf27c PZ |
5257 | |
5258 | again: | |
e7850595 | 5259 | old = val = local64_read(&hwc->period_left); |
7b4b6658 PZ |
5260 | if (val < 0) |
5261 | return 0; | |
15dbf27c | 5262 | |
7b4b6658 PZ |
5263 | nr = div64_u64(period + val, period); |
5264 | offset = nr * period; | |
5265 | val -= offset; | |
e7850595 | 5266 | if (local64_cmpxchg(&hwc->period_left, old, val) != old) |
7b4b6658 | 5267 | goto again; |
15dbf27c | 5268 | |
7b4b6658 | 5269 | return nr; |
15dbf27c PZ |
5270 | } |
5271 | ||
0cff784a | 5272 | static void perf_swevent_overflow(struct perf_event *event, u64 overflow, |
a8b0ca17 | 5273 | struct perf_sample_data *data, |
5622f295 | 5274 | struct pt_regs *regs) |
15dbf27c | 5275 | { |
cdd6c482 | 5276 | struct hw_perf_event *hwc = &event->hw; |
850bc73f | 5277 | int throttle = 0; |
15dbf27c | 5278 | |
0cff784a PZ |
5279 | if (!overflow) |
5280 | overflow = perf_swevent_set_period(event); | |
15dbf27c | 5281 | |
7b4b6658 PZ |
5282 | if (hwc->interrupts == MAX_INTERRUPTS) |
5283 | return; | |
15dbf27c | 5284 | |
7b4b6658 | 5285 | for (; overflow; overflow--) { |
a8b0ca17 | 5286 | if (__perf_event_overflow(event, throttle, |
5622f295 | 5287 | data, regs)) { |
7b4b6658 PZ |
5288 | /* |
5289 | * We inhibit the overflow from happening when | |
5290 | * hwc->interrupts == MAX_INTERRUPTS. | |
5291 | */ | |
5292 | break; | |
5293 | } | |
cf450a73 | 5294 | throttle = 1; |
7b4b6658 | 5295 | } |
15dbf27c PZ |
5296 | } |
5297 | ||
a4eaf7f1 | 5298 | static void perf_swevent_event(struct perf_event *event, u64 nr, |
a8b0ca17 | 5299 | struct perf_sample_data *data, |
5622f295 | 5300 | struct pt_regs *regs) |
7b4b6658 | 5301 | { |
cdd6c482 | 5302 | struct hw_perf_event *hwc = &event->hw; |
d6d020e9 | 5303 | |
e7850595 | 5304 | local64_add(nr, &event->count); |
d6d020e9 | 5305 | |
0cff784a PZ |
5306 | if (!regs) |
5307 | return; | |
5308 | ||
6c7e550f | 5309 | if (!is_sampling_event(event)) |
7b4b6658 | 5310 | return; |
d6d020e9 | 5311 | |
5d81e5cf AV |
5312 | if ((event->attr.sample_type & PERF_SAMPLE_PERIOD) && !event->attr.freq) { |
5313 | data->period = nr; | |
5314 | return perf_swevent_overflow(event, 1, data, regs); | |
5315 | } else | |
5316 | data->period = event->hw.last_period; | |
5317 | ||
0cff784a | 5318 | if (nr == 1 && hwc->sample_period == 1 && !event->attr.freq) |
a8b0ca17 | 5319 | return perf_swevent_overflow(event, 1, data, regs); |
0cff784a | 5320 | |
e7850595 | 5321 | if (local64_add_negative(nr, &hwc->period_left)) |
7b4b6658 | 5322 | return; |
df1a132b | 5323 | |
a8b0ca17 | 5324 | perf_swevent_overflow(event, 0, data, regs); |
d6d020e9 PZ |
5325 | } |
5326 | ||
f5ffe02e FW |
5327 | static int perf_exclude_event(struct perf_event *event, |
5328 | struct pt_regs *regs) | |
5329 | { | |
a4eaf7f1 | 5330 | if (event->hw.state & PERF_HES_STOPPED) |
91b2f482 | 5331 | return 1; |
a4eaf7f1 | 5332 | |
f5ffe02e FW |
5333 | if (regs) { |
5334 | if (event->attr.exclude_user && user_mode(regs)) | |
5335 | return 1; | |
5336 | ||
5337 | if (event->attr.exclude_kernel && !user_mode(regs)) | |
5338 | return 1; | |
5339 | } | |
5340 | ||
5341 | return 0; | |
5342 | } | |
5343 | ||
cdd6c482 | 5344 | static int perf_swevent_match(struct perf_event *event, |
1c432d89 | 5345 | enum perf_type_id type, |
6fb2915d LZ |
5346 | u32 event_id, |
5347 | struct perf_sample_data *data, | |
5348 | struct pt_regs *regs) | |
15dbf27c | 5349 | { |
cdd6c482 | 5350 | if (event->attr.type != type) |
a21ca2ca | 5351 | return 0; |
f5ffe02e | 5352 | |
cdd6c482 | 5353 | if (event->attr.config != event_id) |
15dbf27c PZ |
5354 | return 0; |
5355 | ||
f5ffe02e FW |
5356 | if (perf_exclude_event(event, regs)) |
5357 | return 0; | |
15dbf27c PZ |
5358 | |
5359 | return 1; | |
5360 | } | |
5361 | ||
76e1d904 FW |
5362 | static inline u64 swevent_hash(u64 type, u32 event_id) |
5363 | { | |
5364 | u64 val = event_id | (type << 32); | |
5365 | ||
5366 | return hash_64(val, SWEVENT_HLIST_BITS); | |
5367 | } | |
5368 | ||
49f135ed FW |
5369 | static inline struct hlist_head * |
5370 | __find_swevent_head(struct swevent_hlist *hlist, u64 type, u32 event_id) | |
76e1d904 | 5371 | { |
49f135ed FW |
5372 | u64 hash = swevent_hash(type, event_id); |
5373 | ||
5374 | return &hlist->heads[hash]; | |
5375 | } | |
76e1d904 | 5376 | |
49f135ed FW |
5377 | /* For the read side: events when they trigger */ |
5378 | static inline struct hlist_head * | |
b28ab83c | 5379 | find_swevent_head_rcu(struct swevent_htable *swhash, u64 type, u32 event_id) |
49f135ed FW |
5380 | { |
5381 | struct swevent_hlist *hlist; | |
76e1d904 | 5382 | |
b28ab83c | 5383 | hlist = rcu_dereference(swhash->swevent_hlist); |
76e1d904 FW |
5384 | if (!hlist) |
5385 | return NULL; | |
5386 | ||
49f135ed FW |
5387 | return __find_swevent_head(hlist, type, event_id); |
5388 | } | |
5389 | ||
5390 | /* For the event head insertion and removal in the hlist */ | |
5391 | static inline struct hlist_head * | |
b28ab83c | 5392 | find_swevent_head(struct swevent_htable *swhash, struct perf_event *event) |
49f135ed FW |
5393 | { |
5394 | struct swevent_hlist *hlist; | |
5395 | u32 event_id = event->attr.config; | |
5396 | u64 type = event->attr.type; | |
5397 | ||
5398 | /* | |
5399 | * Event scheduling is always serialized against hlist allocation | |
5400 | * and release. Which makes the protected version suitable here. | |
5401 | * The context lock guarantees that. | |
5402 | */ | |
b28ab83c | 5403 | hlist = rcu_dereference_protected(swhash->swevent_hlist, |
49f135ed FW |
5404 | lockdep_is_held(&event->ctx->lock)); |
5405 | if (!hlist) | |
5406 | return NULL; | |
5407 | ||
5408 | return __find_swevent_head(hlist, type, event_id); | |
76e1d904 FW |
5409 | } |
5410 | ||
5411 | static void do_perf_sw_event(enum perf_type_id type, u32 event_id, | |
a8b0ca17 | 5412 | u64 nr, |
76e1d904 FW |
5413 | struct perf_sample_data *data, |
5414 | struct pt_regs *regs) | |
15dbf27c | 5415 | { |
b28ab83c | 5416 | struct swevent_htable *swhash = &__get_cpu_var(swevent_htable); |
cdd6c482 | 5417 | struct perf_event *event; |
76e1d904 | 5418 | struct hlist_head *head; |
15dbf27c | 5419 | |
76e1d904 | 5420 | rcu_read_lock(); |
b28ab83c | 5421 | head = find_swevent_head_rcu(swhash, type, event_id); |
76e1d904 FW |
5422 | if (!head) |
5423 | goto end; | |
5424 | ||
b67bfe0d | 5425 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
6fb2915d | 5426 | if (perf_swevent_match(event, type, event_id, data, regs)) |
a8b0ca17 | 5427 | perf_swevent_event(event, nr, data, regs); |
15dbf27c | 5428 | } |
76e1d904 FW |
5429 | end: |
5430 | rcu_read_unlock(); | |
15dbf27c PZ |
5431 | } |
5432 | ||
4ed7c92d | 5433 | int perf_swevent_get_recursion_context(void) |
96f6d444 | 5434 | { |
b28ab83c | 5435 | struct swevent_htable *swhash = &__get_cpu_var(swevent_htable); |
96f6d444 | 5436 | |
b28ab83c | 5437 | return get_recursion_context(swhash->recursion); |
96f6d444 | 5438 | } |
645e8cc0 | 5439 | EXPORT_SYMBOL_GPL(perf_swevent_get_recursion_context); |
96f6d444 | 5440 | |
fa9f90be | 5441 | inline void perf_swevent_put_recursion_context(int rctx) |
15dbf27c | 5442 | { |
b28ab83c | 5443 | struct swevent_htable *swhash = &__get_cpu_var(swevent_htable); |
927c7a9e | 5444 | |
b28ab83c | 5445 | put_recursion_context(swhash->recursion, rctx); |
ce71b9df | 5446 | } |
15dbf27c | 5447 | |
a8b0ca17 | 5448 | void __perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) |
b8e83514 | 5449 | { |
a4234bfc | 5450 | struct perf_sample_data data; |
4ed7c92d PZ |
5451 | int rctx; |
5452 | ||
1c024eca | 5453 | preempt_disable_notrace(); |
4ed7c92d PZ |
5454 | rctx = perf_swevent_get_recursion_context(); |
5455 | if (rctx < 0) | |
5456 | return; | |
a4234bfc | 5457 | |
fd0d000b | 5458 | perf_sample_data_init(&data, addr, 0); |
92bf309a | 5459 | |
a8b0ca17 | 5460 | do_perf_sw_event(PERF_TYPE_SOFTWARE, event_id, nr, &data, regs); |
4ed7c92d PZ |
5461 | |
5462 | perf_swevent_put_recursion_context(rctx); | |
1c024eca | 5463 | preempt_enable_notrace(); |
b8e83514 PZ |
5464 | } |
5465 | ||
cdd6c482 | 5466 | static void perf_swevent_read(struct perf_event *event) |
15dbf27c | 5467 | { |
15dbf27c PZ |
5468 | } |
5469 | ||
a4eaf7f1 | 5470 | static int perf_swevent_add(struct perf_event *event, int flags) |
15dbf27c | 5471 | { |
b28ab83c | 5472 | struct swevent_htable *swhash = &__get_cpu_var(swevent_htable); |
cdd6c482 | 5473 | struct hw_perf_event *hwc = &event->hw; |
76e1d904 FW |
5474 | struct hlist_head *head; |
5475 | ||
6c7e550f | 5476 | if (is_sampling_event(event)) { |
7b4b6658 | 5477 | hwc->last_period = hwc->sample_period; |
cdd6c482 | 5478 | perf_swevent_set_period(event); |
7b4b6658 | 5479 | } |
76e1d904 | 5480 | |
a4eaf7f1 PZ |
5481 | hwc->state = !(flags & PERF_EF_START); |
5482 | ||
b28ab83c | 5483 | head = find_swevent_head(swhash, event); |
76e1d904 FW |
5484 | if (WARN_ON_ONCE(!head)) |
5485 | return -EINVAL; | |
5486 | ||
5487 | hlist_add_head_rcu(&event->hlist_entry, head); | |
5488 | ||
15dbf27c PZ |
5489 | return 0; |
5490 | } | |
5491 | ||
a4eaf7f1 | 5492 | static void perf_swevent_del(struct perf_event *event, int flags) |
15dbf27c | 5493 | { |
76e1d904 | 5494 | hlist_del_rcu(&event->hlist_entry); |
15dbf27c PZ |
5495 | } |
5496 | ||
a4eaf7f1 | 5497 | static void perf_swevent_start(struct perf_event *event, int flags) |
5c92d124 | 5498 | { |
a4eaf7f1 | 5499 | event->hw.state = 0; |
d6d020e9 | 5500 | } |
aa9c4c0f | 5501 | |
a4eaf7f1 | 5502 | static void perf_swevent_stop(struct perf_event *event, int flags) |
d6d020e9 | 5503 | { |
a4eaf7f1 | 5504 | event->hw.state = PERF_HES_STOPPED; |
bae43c99 IM |
5505 | } |
5506 | ||
49f135ed FW |
5507 | /* Deref the hlist from the update side */ |
5508 | static inline struct swevent_hlist * | |
b28ab83c | 5509 | swevent_hlist_deref(struct swevent_htable *swhash) |
49f135ed | 5510 | { |
b28ab83c PZ |
5511 | return rcu_dereference_protected(swhash->swevent_hlist, |
5512 | lockdep_is_held(&swhash->hlist_mutex)); | |
49f135ed FW |
5513 | } |
5514 | ||
b28ab83c | 5515 | static void swevent_hlist_release(struct swevent_htable *swhash) |
76e1d904 | 5516 | { |
b28ab83c | 5517 | struct swevent_hlist *hlist = swevent_hlist_deref(swhash); |
76e1d904 | 5518 | |
49f135ed | 5519 | if (!hlist) |
76e1d904 FW |
5520 | return; |
5521 | ||
b28ab83c | 5522 | rcu_assign_pointer(swhash->swevent_hlist, NULL); |
fa4bbc4c | 5523 | kfree_rcu(hlist, rcu_head); |
76e1d904 FW |
5524 | } |
5525 | ||
5526 | static void swevent_hlist_put_cpu(struct perf_event *event, int cpu) | |
5527 | { | |
b28ab83c | 5528 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 | 5529 | |
b28ab83c | 5530 | mutex_lock(&swhash->hlist_mutex); |
76e1d904 | 5531 | |
b28ab83c PZ |
5532 | if (!--swhash->hlist_refcount) |
5533 | swevent_hlist_release(swhash); | |
76e1d904 | 5534 | |
b28ab83c | 5535 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
5536 | } |
5537 | ||
5538 | static void swevent_hlist_put(struct perf_event *event) | |
5539 | { | |
5540 | int cpu; | |
5541 | ||
5542 | if (event->cpu != -1) { | |
5543 | swevent_hlist_put_cpu(event, event->cpu); | |
5544 | return; | |
5545 | } | |
5546 | ||
5547 | for_each_possible_cpu(cpu) | |
5548 | swevent_hlist_put_cpu(event, cpu); | |
5549 | } | |
5550 | ||
5551 | static int swevent_hlist_get_cpu(struct perf_event *event, int cpu) | |
5552 | { | |
b28ab83c | 5553 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 FW |
5554 | int err = 0; |
5555 | ||
b28ab83c | 5556 | mutex_lock(&swhash->hlist_mutex); |
76e1d904 | 5557 | |
b28ab83c | 5558 | if (!swevent_hlist_deref(swhash) && cpu_online(cpu)) { |
76e1d904 FW |
5559 | struct swevent_hlist *hlist; |
5560 | ||
5561 | hlist = kzalloc(sizeof(*hlist), GFP_KERNEL); | |
5562 | if (!hlist) { | |
5563 | err = -ENOMEM; | |
5564 | goto exit; | |
5565 | } | |
b28ab83c | 5566 | rcu_assign_pointer(swhash->swevent_hlist, hlist); |
76e1d904 | 5567 | } |
b28ab83c | 5568 | swhash->hlist_refcount++; |
9ed6060d | 5569 | exit: |
b28ab83c | 5570 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
5571 | |
5572 | return err; | |
5573 | } | |
5574 | ||
5575 | static int swevent_hlist_get(struct perf_event *event) | |
5576 | { | |
5577 | int err; | |
5578 | int cpu, failed_cpu; | |
5579 | ||
5580 | if (event->cpu != -1) | |
5581 | return swevent_hlist_get_cpu(event, event->cpu); | |
5582 | ||
5583 | get_online_cpus(); | |
5584 | for_each_possible_cpu(cpu) { | |
5585 | err = swevent_hlist_get_cpu(event, cpu); | |
5586 | if (err) { | |
5587 | failed_cpu = cpu; | |
5588 | goto fail; | |
5589 | } | |
5590 | } | |
5591 | put_online_cpus(); | |
5592 | ||
5593 | return 0; | |
9ed6060d | 5594 | fail: |
76e1d904 FW |
5595 | for_each_possible_cpu(cpu) { |
5596 | if (cpu == failed_cpu) | |
5597 | break; | |
5598 | swevent_hlist_put_cpu(event, cpu); | |
5599 | } | |
5600 | ||
5601 | put_online_cpus(); | |
5602 | return err; | |
5603 | } | |
5604 | ||
c5905afb | 5605 | struct static_key perf_swevent_enabled[PERF_COUNT_SW_MAX]; |
95476b64 | 5606 | |
b0a873eb PZ |
5607 | static void sw_perf_event_destroy(struct perf_event *event) |
5608 | { | |
5609 | u64 event_id = event->attr.config; | |
95476b64 | 5610 | |
b0a873eb PZ |
5611 | WARN_ON(event->parent); |
5612 | ||
c5905afb | 5613 | static_key_slow_dec(&perf_swevent_enabled[event_id]); |
b0a873eb PZ |
5614 | swevent_hlist_put(event); |
5615 | } | |
5616 | ||
5617 | static int perf_swevent_init(struct perf_event *event) | |
5618 | { | |
8176cced | 5619 | u64 event_id = event->attr.config; |
b0a873eb PZ |
5620 | |
5621 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
5622 | return -ENOENT; | |
5623 | ||
2481c5fa SE |
5624 | /* |
5625 | * no branch sampling for software events | |
5626 | */ | |
5627 | if (has_branch_stack(event)) | |
5628 | return -EOPNOTSUPP; | |
5629 | ||
b0a873eb PZ |
5630 | switch (event_id) { |
5631 | case PERF_COUNT_SW_CPU_CLOCK: | |
5632 | case PERF_COUNT_SW_TASK_CLOCK: | |
5633 | return -ENOENT; | |
5634 | ||
5635 | default: | |
5636 | break; | |
5637 | } | |
5638 | ||
ce677831 | 5639 | if (event_id >= PERF_COUNT_SW_MAX) |
b0a873eb PZ |
5640 | return -ENOENT; |
5641 | ||
5642 | if (!event->parent) { | |
5643 | int err; | |
5644 | ||
5645 | err = swevent_hlist_get(event); | |
5646 | if (err) | |
5647 | return err; | |
5648 | ||
c5905afb | 5649 | static_key_slow_inc(&perf_swevent_enabled[event_id]); |
b0a873eb PZ |
5650 | event->destroy = sw_perf_event_destroy; |
5651 | } | |
5652 | ||
5653 | return 0; | |
5654 | } | |
5655 | ||
35edc2a5 PZ |
5656 | static int perf_swevent_event_idx(struct perf_event *event) |
5657 | { | |
5658 | return 0; | |
5659 | } | |
5660 | ||
b0a873eb | 5661 | static struct pmu perf_swevent = { |
89a1e187 | 5662 | .task_ctx_nr = perf_sw_context, |
95476b64 | 5663 | |
b0a873eb | 5664 | .event_init = perf_swevent_init, |
a4eaf7f1 PZ |
5665 | .add = perf_swevent_add, |
5666 | .del = perf_swevent_del, | |
5667 | .start = perf_swevent_start, | |
5668 | .stop = perf_swevent_stop, | |
1c024eca | 5669 | .read = perf_swevent_read, |
35edc2a5 PZ |
5670 | |
5671 | .event_idx = perf_swevent_event_idx, | |
1c024eca PZ |
5672 | }; |
5673 | ||
b0a873eb PZ |
5674 | #ifdef CONFIG_EVENT_TRACING |
5675 | ||
1c024eca PZ |
5676 | static int perf_tp_filter_match(struct perf_event *event, |
5677 | struct perf_sample_data *data) | |
5678 | { | |
5679 | void *record = data->raw->data; | |
5680 | ||
5681 | if (likely(!event->filter) || filter_match_preds(event->filter, record)) | |
5682 | return 1; | |
5683 | return 0; | |
5684 | } | |
5685 | ||
5686 | static int perf_tp_event_match(struct perf_event *event, | |
5687 | struct perf_sample_data *data, | |
5688 | struct pt_regs *regs) | |
5689 | { | |
a0f7d0f7 FW |
5690 | if (event->hw.state & PERF_HES_STOPPED) |
5691 | return 0; | |
580d607c PZ |
5692 | /* |
5693 | * All tracepoints are from kernel-space. | |
5694 | */ | |
5695 | if (event->attr.exclude_kernel) | |
1c024eca PZ |
5696 | return 0; |
5697 | ||
5698 | if (!perf_tp_filter_match(event, data)) | |
5699 | return 0; | |
5700 | ||
5701 | return 1; | |
5702 | } | |
5703 | ||
5704 | void perf_tp_event(u64 addr, u64 count, void *record, int entry_size, | |
e6dab5ff AV |
5705 | struct pt_regs *regs, struct hlist_head *head, int rctx, |
5706 | struct task_struct *task) | |
95476b64 FW |
5707 | { |
5708 | struct perf_sample_data data; | |
1c024eca | 5709 | struct perf_event *event; |
1c024eca | 5710 | |
95476b64 FW |
5711 | struct perf_raw_record raw = { |
5712 | .size = entry_size, | |
5713 | .data = record, | |
5714 | }; | |
5715 | ||
fd0d000b | 5716 | perf_sample_data_init(&data, addr, 0); |
95476b64 FW |
5717 | data.raw = &raw; |
5718 | ||
b67bfe0d | 5719 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
1c024eca | 5720 | if (perf_tp_event_match(event, &data, regs)) |
a8b0ca17 | 5721 | perf_swevent_event(event, count, &data, regs); |
4f41c013 | 5722 | } |
ecc55f84 | 5723 | |
e6dab5ff AV |
5724 | /* |
5725 | * If we got specified a target task, also iterate its context and | |
5726 | * deliver this event there too. | |
5727 | */ | |
5728 | if (task && task != current) { | |
5729 | struct perf_event_context *ctx; | |
5730 | struct trace_entry *entry = record; | |
5731 | ||
5732 | rcu_read_lock(); | |
5733 | ctx = rcu_dereference(task->perf_event_ctxp[perf_sw_context]); | |
5734 | if (!ctx) | |
5735 | goto unlock; | |
5736 | ||
5737 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
5738 | if (event->attr.type != PERF_TYPE_TRACEPOINT) | |
5739 | continue; | |
5740 | if (event->attr.config != entry->type) | |
5741 | continue; | |
5742 | if (perf_tp_event_match(event, &data, regs)) | |
5743 | perf_swevent_event(event, count, &data, regs); | |
5744 | } | |
5745 | unlock: | |
5746 | rcu_read_unlock(); | |
5747 | } | |
5748 | ||
ecc55f84 | 5749 | perf_swevent_put_recursion_context(rctx); |
95476b64 FW |
5750 | } |
5751 | EXPORT_SYMBOL_GPL(perf_tp_event); | |
5752 | ||
cdd6c482 | 5753 | static void tp_perf_event_destroy(struct perf_event *event) |
e077df4f | 5754 | { |
1c024eca | 5755 | perf_trace_destroy(event); |
e077df4f PZ |
5756 | } |
5757 | ||
b0a873eb | 5758 | static int perf_tp_event_init(struct perf_event *event) |
e077df4f | 5759 | { |
76e1d904 FW |
5760 | int err; |
5761 | ||
b0a873eb PZ |
5762 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
5763 | return -ENOENT; | |
5764 | ||
2481c5fa SE |
5765 | /* |
5766 | * no branch sampling for tracepoint events | |
5767 | */ | |
5768 | if (has_branch_stack(event)) | |
5769 | return -EOPNOTSUPP; | |
5770 | ||
1c024eca PZ |
5771 | err = perf_trace_init(event); |
5772 | if (err) | |
b0a873eb | 5773 | return err; |
e077df4f | 5774 | |
cdd6c482 | 5775 | event->destroy = tp_perf_event_destroy; |
e077df4f | 5776 | |
b0a873eb PZ |
5777 | return 0; |
5778 | } | |
5779 | ||
5780 | static struct pmu perf_tracepoint = { | |
89a1e187 PZ |
5781 | .task_ctx_nr = perf_sw_context, |
5782 | ||
b0a873eb | 5783 | .event_init = perf_tp_event_init, |
a4eaf7f1 PZ |
5784 | .add = perf_trace_add, |
5785 | .del = perf_trace_del, | |
5786 | .start = perf_swevent_start, | |
5787 | .stop = perf_swevent_stop, | |
b0a873eb | 5788 | .read = perf_swevent_read, |
35edc2a5 PZ |
5789 | |
5790 | .event_idx = perf_swevent_event_idx, | |
b0a873eb PZ |
5791 | }; |
5792 | ||
5793 | static inline void perf_tp_register(void) | |
5794 | { | |
2e80a82a | 5795 | perf_pmu_register(&perf_tracepoint, "tracepoint", PERF_TYPE_TRACEPOINT); |
e077df4f | 5796 | } |
6fb2915d LZ |
5797 | |
5798 | static int perf_event_set_filter(struct perf_event *event, void __user *arg) | |
5799 | { | |
5800 | char *filter_str; | |
5801 | int ret; | |
5802 | ||
5803 | if (event->attr.type != PERF_TYPE_TRACEPOINT) | |
5804 | return -EINVAL; | |
5805 | ||
5806 | filter_str = strndup_user(arg, PAGE_SIZE); | |
5807 | if (IS_ERR(filter_str)) | |
5808 | return PTR_ERR(filter_str); | |
5809 | ||
5810 | ret = ftrace_profile_set_filter(event, event->attr.config, filter_str); | |
5811 | ||
5812 | kfree(filter_str); | |
5813 | return ret; | |
5814 | } | |
5815 | ||
5816 | static void perf_event_free_filter(struct perf_event *event) | |
5817 | { | |
5818 | ftrace_profile_free_filter(event); | |
5819 | } | |
5820 | ||
e077df4f | 5821 | #else |
6fb2915d | 5822 | |
b0a873eb | 5823 | static inline void perf_tp_register(void) |
e077df4f | 5824 | { |
e077df4f | 5825 | } |
6fb2915d LZ |
5826 | |
5827 | static int perf_event_set_filter(struct perf_event *event, void __user *arg) | |
5828 | { | |
5829 | return -ENOENT; | |
5830 | } | |
5831 | ||
5832 | static void perf_event_free_filter(struct perf_event *event) | |
5833 | { | |
5834 | } | |
5835 | ||
07b139c8 | 5836 | #endif /* CONFIG_EVENT_TRACING */ |
e077df4f | 5837 | |
24f1e32c | 5838 | #ifdef CONFIG_HAVE_HW_BREAKPOINT |
f5ffe02e | 5839 | void perf_bp_event(struct perf_event *bp, void *data) |
24f1e32c | 5840 | { |
f5ffe02e FW |
5841 | struct perf_sample_data sample; |
5842 | struct pt_regs *regs = data; | |
5843 | ||
fd0d000b | 5844 | perf_sample_data_init(&sample, bp->attr.bp_addr, 0); |
f5ffe02e | 5845 | |
a4eaf7f1 | 5846 | if (!bp->hw.state && !perf_exclude_event(bp, regs)) |
a8b0ca17 | 5847 | perf_swevent_event(bp, 1, &sample, regs); |
24f1e32c FW |
5848 | } |
5849 | #endif | |
5850 | ||
b0a873eb PZ |
5851 | /* |
5852 | * hrtimer based swevent callback | |
5853 | */ | |
f29ac756 | 5854 | |
b0a873eb | 5855 | static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer) |
f29ac756 | 5856 | { |
b0a873eb PZ |
5857 | enum hrtimer_restart ret = HRTIMER_RESTART; |
5858 | struct perf_sample_data data; | |
5859 | struct pt_regs *regs; | |
5860 | struct perf_event *event; | |
5861 | u64 period; | |
f29ac756 | 5862 | |
b0a873eb | 5863 | event = container_of(hrtimer, struct perf_event, hw.hrtimer); |
ba3dd36c PZ |
5864 | |
5865 | if (event->state != PERF_EVENT_STATE_ACTIVE) | |
5866 | return HRTIMER_NORESTART; | |
5867 | ||
b0a873eb | 5868 | event->pmu->read(event); |
f344011c | 5869 | |
fd0d000b | 5870 | perf_sample_data_init(&data, 0, event->hw.last_period); |
b0a873eb PZ |
5871 | regs = get_irq_regs(); |
5872 | ||
5873 | if (regs && !perf_exclude_event(event, regs)) { | |
77aeeebd | 5874 | if (!(event->attr.exclude_idle && is_idle_task(current))) |
33b07b8b | 5875 | if (__perf_event_overflow(event, 1, &data, regs)) |
b0a873eb PZ |
5876 | ret = HRTIMER_NORESTART; |
5877 | } | |
24f1e32c | 5878 | |
b0a873eb PZ |
5879 | period = max_t(u64, 10000, event->hw.sample_period); |
5880 | hrtimer_forward_now(hrtimer, ns_to_ktime(period)); | |
24f1e32c | 5881 | |
b0a873eb | 5882 | return ret; |
f29ac756 PZ |
5883 | } |
5884 | ||
b0a873eb | 5885 | static void perf_swevent_start_hrtimer(struct perf_event *event) |
5c92d124 | 5886 | { |
b0a873eb | 5887 | struct hw_perf_event *hwc = &event->hw; |
5d508e82 FBH |
5888 | s64 period; |
5889 | ||
5890 | if (!is_sampling_event(event)) | |
5891 | return; | |
f5ffe02e | 5892 | |
5d508e82 FBH |
5893 | period = local64_read(&hwc->period_left); |
5894 | if (period) { | |
5895 | if (period < 0) | |
5896 | period = 10000; | |
fa407f35 | 5897 | |
5d508e82 FBH |
5898 | local64_set(&hwc->period_left, 0); |
5899 | } else { | |
5900 | period = max_t(u64, 10000, hwc->sample_period); | |
5901 | } | |
5902 | __hrtimer_start_range_ns(&hwc->hrtimer, | |
b0a873eb | 5903 | ns_to_ktime(period), 0, |
b5ab4cd5 | 5904 | HRTIMER_MODE_REL_PINNED, 0); |
24f1e32c | 5905 | } |
b0a873eb PZ |
5906 | |
5907 | static void perf_swevent_cancel_hrtimer(struct perf_event *event) | |
24f1e32c | 5908 | { |
b0a873eb PZ |
5909 | struct hw_perf_event *hwc = &event->hw; |
5910 | ||
6c7e550f | 5911 | if (is_sampling_event(event)) { |
b0a873eb | 5912 | ktime_t remaining = hrtimer_get_remaining(&hwc->hrtimer); |
fa407f35 | 5913 | local64_set(&hwc->period_left, ktime_to_ns(remaining)); |
b0a873eb PZ |
5914 | |
5915 | hrtimer_cancel(&hwc->hrtimer); | |
5916 | } | |
24f1e32c FW |
5917 | } |
5918 | ||
ba3dd36c PZ |
5919 | static void perf_swevent_init_hrtimer(struct perf_event *event) |
5920 | { | |
5921 | struct hw_perf_event *hwc = &event->hw; | |
5922 | ||
5923 | if (!is_sampling_event(event)) | |
5924 | return; | |
5925 | ||
5926 | hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); | |
5927 | hwc->hrtimer.function = perf_swevent_hrtimer; | |
5928 | ||
5929 | /* | |
5930 | * Since hrtimers have a fixed rate, we can do a static freq->period | |
5931 | * mapping and avoid the whole period adjust feedback stuff. | |
5932 | */ | |
5933 | if (event->attr.freq) { | |
5934 | long freq = event->attr.sample_freq; | |
5935 | ||
5936 | event->attr.sample_period = NSEC_PER_SEC / freq; | |
5937 | hwc->sample_period = event->attr.sample_period; | |
5938 | local64_set(&hwc->period_left, hwc->sample_period); | |
778141e3 | 5939 | hwc->last_period = hwc->sample_period; |
ba3dd36c PZ |
5940 | event->attr.freq = 0; |
5941 | } | |
5942 | } | |
5943 | ||
b0a873eb PZ |
5944 | /* |
5945 | * Software event: cpu wall time clock | |
5946 | */ | |
5947 | ||
5948 | static void cpu_clock_event_update(struct perf_event *event) | |
24f1e32c | 5949 | { |
b0a873eb PZ |
5950 | s64 prev; |
5951 | u64 now; | |
5952 | ||
a4eaf7f1 | 5953 | now = local_clock(); |
b0a873eb PZ |
5954 | prev = local64_xchg(&event->hw.prev_count, now); |
5955 | local64_add(now - prev, &event->count); | |
24f1e32c | 5956 | } |
24f1e32c | 5957 | |
a4eaf7f1 | 5958 | static void cpu_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 5959 | { |
a4eaf7f1 | 5960 | local64_set(&event->hw.prev_count, local_clock()); |
b0a873eb | 5961 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
5962 | } |
5963 | ||
a4eaf7f1 | 5964 | static void cpu_clock_event_stop(struct perf_event *event, int flags) |
f29ac756 | 5965 | { |
b0a873eb PZ |
5966 | perf_swevent_cancel_hrtimer(event); |
5967 | cpu_clock_event_update(event); | |
5968 | } | |
f29ac756 | 5969 | |
a4eaf7f1 PZ |
5970 | static int cpu_clock_event_add(struct perf_event *event, int flags) |
5971 | { | |
5972 | if (flags & PERF_EF_START) | |
5973 | cpu_clock_event_start(event, flags); | |
5974 | ||
5975 | return 0; | |
5976 | } | |
5977 | ||
5978 | static void cpu_clock_event_del(struct perf_event *event, int flags) | |
5979 | { | |
5980 | cpu_clock_event_stop(event, flags); | |
5981 | } | |
5982 | ||
b0a873eb PZ |
5983 | static void cpu_clock_event_read(struct perf_event *event) |
5984 | { | |
5985 | cpu_clock_event_update(event); | |
5986 | } | |
f344011c | 5987 | |
b0a873eb PZ |
5988 | static int cpu_clock_event_init(struct perf_event *event) |
5989 | { | |
5990 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
5991 | return -ENOENT; | |
5992 | ||
5993 | if (event->attr.config != PERF_COUNT_SW_CPU_CLOCK) | |
5994 | return -ENOENT; | |
5995 | ||
2481c5fa SE |
5996 | /* |
5997 | * no branch sampling for software events | |
5998 | */ | |
5999 | if (has_branch_stack(event)) | |
6000 | return -EOPNOTSUPP; | |
6001 | ||
ba3dd36c PZ |
6002 | perf_swevent_init_hrtimer(event); |
6003 | ||
b0a873eb | 6004 | return 0; |
f29ac756 PZ |
6005 | } |
6006 | ||
b0a873eb | 6007 | static struct pmu perf_cpu_clock = { |
89a1e187 PZ |
6008 | .task_ctx_nr = perf_sw_context, |
6009 | ||
b0a873eb | 6010 | .event_init = cpu_clock_event_init, |
a4eaf7f1 PZ |
6011 | .add = cpu_clock_event_add, |
6012 | .del = cpu_clock_event_del, | |
6013 | .start = cpu_clock_event_start, | |
6014 | .stop = cpu_clock_event_stop, | |
b0a873eb | 6015 | .read = cpu_clock_event_read, |
35edc2a5 PZ |
6016 | |
6017 | .event_idx = perf_swevent_event_idx, | |
b0a873eb PZ |
6018 | }; |
6019 | ||
6020 | /* | |
6021 | * Software event: task time clock | |
6022 | */ | |
6023 | ||
6024 | static void task_clock_event_update(struct perf_event *event, u64 now) | |
5c92d124 | 6025 | { |
b0a873eb PZ |
6026 | u64 prev; |
6027 | s64 delta; | |
5c92d124 | 6028 | |
b0a873eb PZ |
6029 | prev = local64_xchg(&event->hw.prev_count, now); |
6030 | delta = now - prev; | |
6031 | local64_add(delta, &event->count); | |
6032 | } | |
5c92d124 | 6033 | |
a4eaf7f1 | 6034 | static void task_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 6035 | { |
a4eaf7f1 | 6036 | local64_set(&event->hw.prev_count, event->ctx->time); |
b0a873eb | 6037 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
6038 | } |
6039 | ||
a4eaf7f1 | 6040 | static void task_clock_event_stop(struct perf_event *event, int flags) |
b0a873eb PZ |
6041 | { |
6042 | perf_swevent_cancel_hrtimer(event); | |
6043 | task_clock_event_update(event, event->ctx->time); | |
a4eaf7f1 PZ |
6044 | } |
6045 | ||
6046 | static int task_clock_event_add(struct perf_event *event, int flags) | |
6047 | { | |
6048 | if (flags & PERF_EF_START) | |
6049 | task_clock_event_start(event, flags); | |
b0a873eb | 6050 | |
a4eaf7f1 PZ |
6051 | return 0; |
6052 | } | |
6053 | ||
6054 | static void task_clock_event_del(struct perf_event *event, int flags) | |
6055 | { | |
6056 | task_clock_event_stop(event, PERF_EF_UPDATE); | |
b0a873eb PZ |
6057 | } |
6058 | ||
6059 | static void task_clock_event_read(struct perf_event *event) | |
6060 | { | |
768a06e2 PZ |
6061 | u64 now = perf_clock(); |
6062 | u64 delta = now - event->ctx->timestamp; | |
6063 | u64 time = event->ctx->time + delta; | |
b0a873eb PZ |
6064 | |
6065 | task_clock_event_update(event, time); | |
6066 | } | |
6067 | ||
6068 | static int task_clock_event_init(struct perf_event *event) | |
6fb2915d | 6069 | { |
b0a873eb PZ |
6070 | if (event->attr.type != PERF_TYPE_SOFTWARE) |
6071 | return -ENOENT; | |
6072 | ||
6073 | if (event->attr.config != PERF_COUNT_SW_TASK_CLOCK) | |
6074 | return -ENOENT; | |
6075 | ||
2481c5fa SE |
6076 | /* |
6077 | * no branch sampling for software events | |
6078 | */ | |
6079 | if (has_branch_stack(event)) | |
6080 | return -EOPNOTSUPP; | |
6081 | ||
ba3dd36c PZ |
6082 | perf_swevent_init_hrtimer(event); |
6083 | ||
b0a873eb | 6084 | return 0; |
6fb2915d LZ |
6085 | } |
6086 | ||
b0a873eb | 6087 | static struct pmu perf_task_clock = { |
89a1e187 PZ |
6088 | .task_ctx_nr = perf_sw_context, |
6089 | ||
b0a873eb | 6090 | .event_init = task_clock_event_init, |
a4eaf7f1 PZ |
6091 | .add = task_clock_event_add, |
6092 | .del = task_clock_event_del, | |
6093 | .start = task_clock_event_start, | |
6094 | .stop = task_clock_event_stop, | |
b0a873eb | 6095 | .read = task_clock_event_read, |
35edc2a5 PZ |
6096 | |
6097 | .event_idx = perf_swevent_event_idx, | |
b0a873eb | 6098 | }; |
6fb2915d | 6099 | |
ad5133b7 | 6100 | static void perf_pmu_nop_void(struct pmu *pmu) |
e077df4f | 6101 | { |
e077df4f | 6102 | } |
6fb2915d | 6103 | |
ad5133b7 | 6104 | static int perf_pmu_nop_int(struct pmu *pmu) |
6fb2915d | 6105 | { |
ad5133b7 | 6106 | return 0; |
6fb2915d LZ |
6107 | } |
6108 | ||
ad5133b7 | 6109 | static void perf_pmu_start_txn(struct pmu *pmu) |
6fb2915d | 6110 | { |
ad5133b7 | 6111 | perf_pmu_disable(pmu); |
6fb2915d LZ |
6112 | } |
6113 | ||
ad5133b7 PZ |
6114 | static int perf_pmu_commit_txn(struct pmu *pmu) |
6115 | { | |
6116 | perf_pmu_enable(pmu); | |
6117 | return 0; | |
6118 | } | |
e077df4f | 6119 | |
ad5133b7 | 6120 | static void perf_pmu_cancel_txn(struct pmu *pmu) |
24f1e32c | 6121 | { |
ad5133b7 | 6122 | perf_pmu_enable(pmu); |
24f1e32c FW |
6123 | } |
6124 | ||
35edc2a5 PZ |
6125 | static int perf_event_idx_default(struct perf_event *event) |
6126 | { | |
6127 | return event->hw.idx + 1; | |
6128 | } | |
6129 | ||
8dc85d54 PZ |
6130 | /* |
6131 | * Ensures all contexts with the same task_ctx_nr have the same | |
6132 | * pmu_cpu_context too. | |
6133 | */ | |
6134 | static void *find_pmu_context(int ctxn) | |
24f1e32c | 6135 | { |
8dc85d54 | 6136 | struct pmu *pmu; |
b326e956 | 6137 | |
8dc85d54 PZ |
6138 | if (ctxn < 0) |
6139 | return NULL; | |
24f1e32c | 6140 | |
8dc85d54 PZ |
6141 | list_for_each_entry(pmu, &pmus, entry) { |
6142 | if (pmu->task_ctx_nr == ctxn) | |
6143 | return pmu->pmu_cpu_context; | |
6144 | } | |
24f1e32c | 6145 | |
8dc85d54 | 6146 | return NULL; |
24f1e32c FW |
6147 | } |
6148 | ||
51676957 | 6149 | static void update_pmu_context(struct pmu *pmu, struct pmu *old_pmu) |
24f1e32c | 6150 | { |
51676957 PZ |
6151 | int cpu; |
6152 | ||
6153 | for_each_possible_cpu(cpu) { | |
6154 | struct perf_cpu_context *cpuctx; | |
6155 | ||
6156 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
6157 | ||
3f1f3320 PZ |
6158 | if (cpuctx->unique_pmu == old_pmu) |
6159 | cpuctx->unique_pmu = pmu; | |
51676957 PZ |
6160 | } |
6161 | } | |
6162 | ||
6163 | static void free_pmu_context(struct pmu *pmu) | |
6164 | { | |
6165 | struct pmu *i; | |
f5ffe02e | 6166 | |
8dc85d54 | 6167 | mutex_lock(&pmus_lock); |
0475f9ea | 6168 | /* |
8dc85d54 | 6169 | * Like a real lame refcount. |
0475f9ea | 6170 | */ |
51676957 PZ |
6171 | list_for_each_entry(i, &pmus, entry) { |
6172 | if (i->pmu_cpu_context == pmu->pmu_cpu_context) { | |
6173 | update_pmu_context(i, pmu); | |
8dc85d54 | 6174 | goto out; |
51676957 | 6175 | } |
8dc85d54 | 6176 | } |
d6d020e9 | 6177 | |
51676957 | 6178 | free_percpu(pmu->pmu_cpu_context); |
8dc85d54 PZ |
6179 | out: |
6180 | mutex_unlock(&pmus_lock); | |
24f1e32c | 6181 | } |
2e80a82a | 6182 | static struct idr pmu_idr; |
d6d020e9 | 6183 | |
abe43400 PZ |
6184 | static ssize_t |
6185 | type_show(struct device *dev, struct device_attribute *attr, char *page) | |
6186 | { | |
6187 | struct pmu *pmu = dev_get_drvdata(dev); | |
6188 | ||
6189 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->type); | |
6190 | } | |
6191 | ||
62b85639 SE |
6192 | static ssize_t |
6193 | perf_event_mux_interval_ms_show(struct device *dev, | |
6194 | struct device_attribute *attr, | |
6195 | char *page) | |
6196 | { | |
6197 | struct pmu *pmu = dev_get_drvdata(dev); | |
6198 | ||
6199 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->hrtimer_interval_ms); | |
6200 | } | |
6201 | ||
6202 | static ssize_t | |
6203 | perf_event_mux_interval_ms_store(struct device *dev, | |
6204 | struct device_attribute *attr, | |
6205 | const char *buf, size_t count) | |
6206 | { | |
6207 | struct pmu *pmu = dev_get_drvdata(dev); | |
6208 | int timer, cpu, ret; | |
6209 | ||
6210 | ret = kstrtoint(buf, 0, &timer); | |
6211 | if (ret) | |
6212 | return ret; | |
6213 | ||
6214 | if (timer < 1) | |
6215 | return -EINVAL; | |
6216 | ||
6217 | /* same value, noting to do */ | |
6218 | if (timer == pmu->hrtimer_interval_ms) | |
6219 | return count; | |
6220 | ||
6221 | pmu->hrtimer_interval_ms = timer; | |
6222 | ||
6223 | /* update all cpuctx for this PMU */ | |
6224 | for_each_possible_cpu(cpu) { | |
6225 | struct perf_cpu_context *cpuctx; | |
6226 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
6227 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * timer); | |
6228 | ||
6229 | if (hrtimer_active(&cpuctx->hrtimer)) | |
6230 | hrtimer_forward_now(&cpuctx->hrtimer, cpuctx->hrtimer_interval); | |
6231 | } | |
6232 | ||
6233 | return count; | |
6234 | } | |
6235 | ||
abe43400 | 6236 | static struct device_attribute pmu_dev_attrs[] = { |
62b85639 SE |
6237 | __ATTR_RO(type), |
6238 | __ATTR_RW(perf_event_mux_interval_ms), | |
6239 | __ATTR_NULL, | |
abe43400 PZ |
6240 | }; |
6241 | ||
6242 | static int pmu_bus_running; | |
6243 | static struct bus_type pmu_bus = { | |
6244 | .name = "event_source", | |
6245 | .dev_attrs = pmu_dev_attrs, | |
6246 | }; | |
6247 | ||
6248 | static void pmu_dev_release(struct device *dev) | |
6249 | { | |
6250 | kfree(dev); | |
6251 | } | |
6252 | ||
6253 | static int pmu_dev_alloc(struct pmu *pmu) | |
6254 | { | |
6255 | int ret = -ENOMEM; | |
6256 | ||
6257 | pmu->dev = kzalloc(sizeof(struct device), GFP_KERNEL); | |
6258 | if (!pmu->dev) | |
6259 | goto out; | |
6260 | ||
0c9d42ed | 6261 | pmu->dev->groups = pmu->attr_groups; |
abe43400 PZ |
6262 | device_initialize(pmu->dev); |
6263 | ret = dev_set_name(pmu->dev, "%s", pmu->name); | |
6264 | if (ret) | |
6265 | goto free_dev; | |
6266 | ||
6267 | dev_set_drvdata(pmu->dev, pmu); | |
6268 | pmu->dev->bus = &pmu_bus; | |
6269 | pmu->dev->release = pmu_dev_release; | |
6270 | ret = device_add(pmu->dev); | |
6271 | if (ret) | |
6272 | goto free_dev; | |
6273 | ||
6274 | out: | |
6275 | return ret; | |
6276 | ||
6277 | free_dev: | |
6278 | put_device(pmu->dev); | |
6279 | goto out; | |
6280 | } | |
6281 | ||
547e9fd7 | 6282 | static struct lock_class_key cpuctx_mutex; |
facc4307 | 6283 | static struct lock_class_key cpuctx_lock; |
547e9fd7 | 6284 | |
03d8e80b | 6285 | int perf_pmu_register(struct pmu *pmu, const char *name, int type) |
24f1e32c | 6286 | { |
108b02cf | 6287 | int cpu, ret; |
24f1e32c | 6288 | |
b0a873eb | 6289 | mutex_lock(&pmus_lock); |
33696fc0 PZ |
6290 | ret = -ENOMEM; |
6291 | pmu->pmu_disable_count = alloc_percpu(int); | |
6292 | if (!pmu->pmu_disable_count) | |
6293 | goto unlock; | |
f29ac756 | 6294 | |
2e80a82a PZ |
6295 | pmu->type = -1; |
6296 | if (!name) | |
6297 | goto skip_type; | |
6298 | pmu->name = name; | |
6299 | ||
6300 | if (type < 0) { | |
0e9c3be2 TH |
6301 | type = idr_alloc(&pmu_idr, pmu, PERF_TYPE_MAX, 0, GFP_KERNEL); |
6302 | if (type < 0) { | |
6303 | ret = type; | |
2e80a82a PZ |
6304 | goto free_pdc; |
6305 | } | |
6306 | } | |
6307 | pmu->type = type; | |
6308 | ||
abe43400 PZ |
6309 | if (pmu_bus_running) { |
6310 | ret = pmu_dev_alloc(pmu); | |
6311 | if (ret) | |
6312 | goto free_idr; | |
6313 | } | |
6314 | ||
2e80a82a | 6315 | skip_type: |
8dc85d54 PZ |
6316 | pmu->pmu_cpu_context = find_pmu_context(pmu->task_ctx_nr); |
6317 | if (pmu->pmu_cpu_context) | |
6318 | goto got_cpu_context; | |
f29ac756 | 6319 | |
c4814202 | 6320 | ret = -ENOMEM; |
108b02cf PZ |
6321 | pmu->pmu_cpu_context = alloc_percpu(struct perf_cpu_context); |
6322 | if (!pmu->pmu_cpu_context) | |
abe43400 | 6323 | goto free_dev; |
f344011c | 6324 | |
108b02cf PZ |
6325 | for_each_possible_cpu(cpu) { |
6326 | struct perf_cpu_context *cpuctx; | |
6327 | ||
6328 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
eb184479 | 6329 | __perf_event_init_context(&cpuctx->ctx); |
547e9fd7 | 6330 | lockdep_set_class(&cpuctx->ctx.mutex, &cpuctx_mutex); |
facc4307 | 6331 | lockdep_set_class(&cpuctx->ctx.lock, &cpuctx_lock); |
b04243ef | 6332 | cpuctx->ctx.type = cpu_context; |
108b02cf | 6333 | cpuctx->ctx.pmu = pmu; |
9e630205 SE |
6334 | |
6335 | __perf_cpu_hrtimer_init(cpuctx, cpu); | |
6336 | ||
e9d2b064 | 6337 | INIT_LIST_HEAD(&cpuctx->rotation_list); |
3f1f3320 | 6338 | cpuctx->unique_pmu = pmu; |
108b02cf | 6339 | } |
76e1d904 | 6340 | |
8dc85d54 | 6341 | got_cpu_context: |
ad5133b7 PZ |
6342 | if (!pmu->start_txn) { |
6343 | if (pmu->pmu_enable) { | |
6344 | /* | |
6345 | * If we have pmu_enable/pmu_disable calls, install | |
6346 | * transaction stubs that use that to try and batch | |
6347 | * hardware accesses. | |
6348 | */ | |
6349 | pmu->start_txn = perf_pmu_start_txn; | |
6350 | pmu->commit_txn = perf_pmu_commit_txn; | |
6351 | pmu->cancel_txn = perf_pmu_cancel_txn; | |
6352 | } else { | |
6353 | pmu->start_txn = perf_pmu_nop_void; | |
6354 | pmu->commit_txn = perf_pmu_nop_int; | |
6355 | pmu->cancel_txn = perf_pmu_nop_void; | |
f344011c | 6356 | } |
5c92d124 | 6357 | } |
15dbf27c | 6358 | |
ad5133b7 PZ |
6359 | if (!pmu->pmu_enable) { |
6360 | pmu->pmu_enable = perf_pmu_nop_void; | |
6361 | pmu->pmu_disable = perf_pmu_nop_void; | |
6362 | } | |
6363 | ||
35edc2a5 PZ |
6364 | if (!pmu->event_idx) |
6365 | pmu->event_idx = perf_event_idx_default; | |
6366 | ||
b0a873eb | 6367 | list_add_rcu(&pmu->entry, &pmus); |
33696fc0 PZ |
6368 | ret = 0; |
6369 | unlock: | |
b0a873eb PZ |
6370 | mutex_unlock(&pmus_lock); |
6371 | ||
33696fc0 | 6372 | return ret; |
108b02cf | 6373 | |
abe43400 PZ |
6374 | free_dev: |
6375 | device_del(pmu->dev); | |
6376 | put_device(pmu->dev); | |
6377 | ||
2e80a82a PZ |
6378 | free_idr: |
6379 | if (pmu->type >= PERF_TYPE_MAX) | |
6380 | idr_remove(&pmu_idr, pmu->type); | |
6381 | ||
108b02cf PZ |
6382 | free_pdc: |
6383 | free_percpu(pmu->pmu_disable_count); | |
6384 | goto unlock; | |
f29ac756 PZ |
6385 | } |
6386 | ||
b0a873eb | 6387 | void perf_pmu_unregister(struct pmu *pmu) |
5c92d124 | 6388 | { |
b0a873eb PZ |
6389 | mutex_lock(&pmus_lock); |
6390 | list_del_rcu(&pmu->entry); | |
6391 | mutex_unlock(&pmus_lock); | |
5c92d124 | 6392 | |
0475f9ea | 6393 | /* |
cde8e884 PZ |
6394 | * We dereference the pmu list under both SRCU and regular RCU, so |
6395 | * synchronize against both of those. | |
0475f9ea | 6396 | */ |
b0a873eb | 6397 | synchronize_srcu(&pmus_srcu); |
cde8e884 | 6398 | synchronize_rcu(); |
d6d020e9 | 6399 | |
33696fc0 | 6400 | free_percpu(pmu->pmu_disable_count); |
2e80a82a PZ |
6401 | if (pmu->type >= PERF_TYPE_MAX) |
6402 | idr_remove(&pmu_idr, pmu->type); | |
abe43400 PZ |
6403 | device_del(pmu->dev); |
6404 | put_device(pmu->dev); | |
51676957 | 6405 | free_pmu_context(pmu); |
b0a873eb | 6406 | } |
d6d020e9 | 6407 | |
b0a873eb PZ |
6408 | struct pmu *perf_init_event(struct perf_event *event) |
6409 | { | |
6410 | struct pmu *pmu = NULL; | |
6411 | int idx; | |
940c5b29 | 6412 | int ret; |
b0a873eb PZ |
6413 | |
6414 | idx = srcu_read_lock(&pmus_srcu); | |
2e80a82a PZ |
6415 | |
6416 | rcu_read_lock(); | |
6417 | pmu = idr_find(&pmu_idr, event->attr.type); | |
6418 | rcu_read_unlock(); | |
940c5b29 | 6419 | if (pmu) { |
7e5b2a01 | 6420 | event->pmu = pmu; |
940c5b29 LM |
6421 | ret = pmu->event_init(event); |
6422 | if (ret) | |
6423 | pmu = ERR_PTR(ret); | |
2e80a82a | 6424 | goto unlock; |
940c5b29 | 6425 | } |
2e80a82a | 6426 | |
b0a873eb | 6427 | list_for_each_entry_rcu(pmu, &pmus, entry) { |
7e5b2a01 | 6428 | event->pmu = pmu; |
940c5b29 | 6429 | ret = pmu->event_init(event); |
b0a873eb | 6430 | if (!ret) |
e5f4d339 | 6431 | goto unlock; |
76e1d904 | 6432 | |
b0a873eb PZ |
6433 | if (ret != -ENOENT) { |
6434 | pmu = ERR_PTR(ret); | |
e5f4d339 | 6435 | goto unlock; |
f344011c | 6436 | } |
5c92d124 | 6437 | } |
e5f4d339 PZ |
6438 | pmu = ERR_PTR(-ENOENT); |
6439 | unlock: | |
b0a873eb | 6440 | srcu_read_unlock(&pmus_srcu, idx); |
15dbf27c | 6441 | |
4aeb0b42 | 6442 | return pmu; |
5c92d124 IM |
6443 | } |
6444 | ||
0793a61d | 6445 | /* |
cdd6c482 | 6446 | * Allocate and initialize a event structure |
0793a61d | 6447 | */ |
cdd6c482 | 6448 | static struct perf_event * |
c3f00c70 | 6449 | perf_event_alloc(struct perf_event_attr *attr, int cpu, |
d580ff86 PZ |
6450 | struct task_struct *task, |
6451 | struct perf_event *group_leader, | |
6452 | struct perf_event *parent_event, | |
4dc0da86 AK |
6453 | perf_overflow_handler_t overflow_handler, |
6454 | void *context) | |
0793a61d | 6455 | { |
51b0fe39 | 6456 | struct pmu *pmu; |
cdd6c482 IM |
6457 | struct perf_event *event; |
6458 | struct hw_perf_event *hwc; | |
d5d2bc0d | 6459 | long err; |
0793a61d | 6460 | |
66832eb4 ON |
6461 | if ((unsigned)cpu >= nr_cpu_ids) { |
6462 | if (!task || cpu != -1) | |
6463 | return ERR_PTR(-EINVAL); | |
6464 | } | |
6465 | ||
c3f00c70 | 6466 | event = kzalloc(sizeof(*event), GFP_KERNEL); |
cdd6c482 | 6467 | if (!event) |
d5d2bc0d | 6468 | return ERR_PTR(-ENOMEM); |
0793a61d | 6469 | |
04289bb9 | 6470 | /* |
cdd6c482 | 6471 | * Single events are their own group leaders, with an |
04289bb9 IM |
6472 | * empty sibling list: |
6473 | */ | |
6474 | if (!group_leader) | |
cdd6c482 | 6475 | group_leader = event; |
04289bb9 | 6476 | |
cdd6c482 IM |
6477 | mutex_init(&event->child_mutex); |
6478 | INIT_LIST_HEAD(&event->child_list); | |
fccc714b | 6479 | |
cdd6c482 IM |
6480 | INIT_LIST_HEAD(&event->group_entry); |
6481 | INIT_LIST_HEAD(&event->event_entry); | |
6482 | INIT_LIST_HEAD(&event->sibling_list); | |
10c6db11 PZ |
6483 | INIT_LIST_HEAD(&event->rb_entry); |
6484 | ||
cdd6c482 | 6485 | init_waitqueue_head(&event->waitq); |
e360adbe | 6486 | init_irq_work(&event->pending, perf_pending_event); |
0793a61d | 6487 | |
cdd6c482 | 6488 | mutex_init(&event->mmap_mutex); |
7b732a75 | 6489 | |
a6fa941d | 6490 | atomic_long_set(&event->refcount, 1); |
cdd6c482 IM |
6491 | event->cpu = cpu; |
6492 | event->attr = *attr; | |
6493 | event->group_leader = group_leader; | |
6494 | event->pmu = NULL; | |
cdd6c482 | 6495 | event->oncpu = -1; |
a96bbc16 | 6496 | |
cdd6c482 | 6497 | event->parent = parent_event; |
b84fbc9f | 6498 | |
17cf22c3 | 6499 | event->ns = get_pid_ns(task_active_pid_ns(current)); |
cdd6c482 | 6500 | event->id = atomic64_inc_return(&perf_event_id); |
a96bbc16 | 6501 | |
cdd6c482 | 6502 | event->state = PERF_EVENT_STATE_INACTIVE; |
329d876d | 6503 | |
d580ff86 PZ |
6504 | if (task) { |
6505 | event->attach_state = PERF_ATTACH_TASK; | |
f22c1bb6 ON |
6506 | |
6507 | if (attr->type == PERF_TYPE_TRACEPOINT) | |
6508 | event->hw.tp_target = task; | |
d580ff86 PZ |
6509 | #ifdef CONFIG_HAVE_HW_BREAKPOINT |
6510 | /* | |
6511 | * hw_breakpoint is a bit difficult here.. | |
6512 | */ | |
f22c1bb6 | 6513 | else if (attr->type == PERF_TYPE_BREAKPOINT) |
d580ff86 PZ |
6514 | event->hw.bp_target = task; |
6515 | #endif | |
6516 | } | |
6517 | ||
4dc0da86 | 6518 | if (!overflow_handler && parent_event) { |
b326e956 | 6519 | overflow_handler = parent_event->overflow_handler; |
4dc0da86 AK |
6520 | context = parent_event->overflow_handler_context; |
6521 | } | |
66832eb4 | 6522 | |
b326e956 | 6523 | event->overflow_handler = overflow_handler; |
4dc0da86 | 6524 | event->overflow_handler_context = context; |
97eaf530 | 6525 | |
0231bb53 | 6526 | perf_event__state_init(event); |
a86ed508 | 6527 | |
4aeb0b42 | 6528 | pmu = NULL; |
b8e83514 | 6529 | |
cdd6c482 | 6530 | hwc = &event->hw; |
bd2b5b12 | 6531 | hwc->sample_period = attr->sample_period; |
0d48696f | 6532 | if (attr->freq && attr->sample_freq) |
bd2b5b12 | 6533 | hwc->sample_period = 1; |
eced1dfc | 6534 | hwc->last_period = hwc->sample_period; |
bd2b5b12 | 6535 | |
e7850595 | 6536 | local64_set(&hwc->period_left, hwc->sample_period); |
60db5e09 | 6537 | |
2023b359 | 6538 | /* |
cdd6c482 | 6539 | * we currently do not support PERF_FORMAT_GROUP on inherited events |
2023b359 | 6540 | */ |
3dab77fb | 6541 | if (attr->inherit && (attr->read_format & PERF_FORMAT_GROUP)) |
2023b359 PZ |
6542 | goto done; |
6543 | ||
b0a873eb | 6544 | pmu = perf_init_event(event); |
974802ea | 6545 | |
d5d2bc0d PM |
6546 | done: |
6547 | err = 0; | |
4aeb0b42 | 6548 | if (!pmu) |
d5d2bc0d | 6549 | err = -EINVAL; |
4aeb0b42 RR |
6550 | else if (IS_ERR(pmu)) |
6551 | err = PTR_ERR(pmu); | |
5c92d124 | 6552 | |
d5d2bc0d | 6553 | if (err) { |
cdd6c482 IM |
6554 | if (event->ns) |
6555 | put_pid_ns(event->ns); | |
6556 | kfree(event); | |
d5d2bc0d | 6557 | return ERR_PTR(err); |
621a01ea | 6558 | } |
d5d2bc0d | 6559 | |
cdd6c482 | 6560 | if (!event->parent) { |
82cd6def | 6561 | if (event->attach_state & PERF_ATTACH_TASK) |
c5905afb | 6562 | static_key_slow_inc(&perf_sched_events.key); |
3af9e859 | 6563 | if (event->attr.mmap || event->attr.mmap_data) |
cdd6c482 IM |
6564 | atomic_inc(&nr_mmap_events); |
6565 | if (event->attr.comm) | |
6566 | atomic_inc(&nr_comm_events); | |
6567 | if (event->attr.task) | |
6568 | atomic_inc(&nr_task_events); | |
927c7a9e FW |
6569 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) { |
6570 | err = get_callchain_buffers(); | |
6571 | if (err) { | |
6572 | free_event(event); | |
6573 | return ERR_PTR(err); | |
6574 | } | |
6575 | } | |
d010b332 SE |
6576 | if (has_branch_stack(event)) { |
6577 | static_key_slow_inc(&perf_sched_events.key); | |
6578 | if (!(event->attach_state & PERF_ATTACH_TASK)) | |
6579 | atomic_inc(&per_cpu(perf_branch_stack_events, | |
6580 | event->cpu)); | |
6581 | } | |
f344011c | 6582 | } |
9ee318a7 | 6583 | |
cdd6c482 | 6584 | return event; |
0793a61d TG |
6585 | } |
6586 | ||
cdd6c482 IM |
6587 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
6588 | struct perf_event_attr *attr) | |
974802ea | 6589 | { |
974802ea | 6590 | u32 size; |
cdf8073d | 6591 | int ret; |
974802ea PZ |
6592 | |
6593 | if (!access_ok(VERIFY_WRITE, uattr, PERF_ATTR_SIZE_VER0)) | |
6594 | return -EFAULT; | |
6595 | ||
6596 | /* | |
6597 | * zero the full structure, so that a short copy will be nice. | |
6598 | */ | |
6599 | memset(attr, 0, sizeof(*attr)); | |
6600 | ||
6601 | ret = get_user(size, &uattr->size); | |
6602 | if (ret) | |
6603 | return ret; | |
6604 | ||
6605 | if (size > PAGE_SIZE) /* silly large */ | |
6606 | goto err_size; | |
6607 | ||
6608 | if (!size) /* abi compat */ | |
6609 | size = PERF_ATTR_SIZE_VER0; | |
6610 | ||
6611 | if (size < PERF_ATTR_SIZE_VER0) | |
6612 | goto err_size; | |
6613 | ||
6614 | /* | |
6615 | * If we're handed a bigger struct than we know of, | |
cdf8073d IS |
6616 | * ensure all the unknown bits are 0 - i.e. new |
6617 | * user-space does not rely on any kernel feature | |
6618 | * extensions we dont know about yet. | |
974802ea PZ |
6619 | */ |
6620 | if (size > sizeof(*attr)) { | |
cdf8073d IS |
6621 | unsigned char __user *addr; |
6622 | unsigned char __user *end; | |
6623 | unsigned char val; | |
974802ea | 6624 | |
cdf8073d IS |
6625 | addr = (void __user *)uattr + sizeof(*attr); |
6626 | end = (void __user *)uattr + size; | |
974802ea | 6627 | |
cdf8073d | 6628 | for (; addr < end; addr++) { |
974802ea PZ |
6629 | ret = get_user(val, addr); |
6630 | if (ret) | |
6631 | return ret; | |
6632 | if (val) | |
6633 | goto err_size; | |
6634 | } | |
b3e62e35 | 6635 | size = sizeof(*attr); |
974802ea PZ |
6636 | } |
6637 | ||
6638 | ret = copy_from_user(attr, uattr, size); | |
6639 | if (ret) | |
6640 | return -EFAULT; | |
6641 | ||
cd757645 | 6642 | if (attr->__reserved_1) |
974802ea PZ |
6643 | return -EINVAL; |
6644 | ||
6645 | if (attr->sample_type & ~(PERF_SAMPLE_MAX-1)) | |
6646 | return -EINVAL; | |
6647 | ||
6648 | if (attr->read_format & ~(PERF_FORMAT_MAX-1)) | |
6649 | return -EINVAL; | |
6650 | ||
bce38cd5 SE |
6651 | if (attr->sample_type & PERF_SAMPLE_BRANCH_STACK) { |
6652 | u64 mask = attr->branch_sample_type; | |
6653 | ||
6654 | /* only using defined bits */ | |
6655 | if (mask & ~(PERF_SAMPLE_BRANCH_MAX-1)) | |
6656 | return -EINVAL; | |
6657 | ||
6658 | /* at least one branch bit must be set */ | |
6659 | if (!(mask & ~PERF_SAMPLE_BRANCH_PLM_ALL)) | |
6660 | return -EINVAL; | |
6661 | ||
bce38cd5 SE |
6662 | /* propagate priv level, when not set for branch */ |
6663 | if (!(mask & PERF_SAMPLE_BRANCH_PLM_ALL)) { | |
6664 | ||
6665 | /* exclude_kernel checked on syscall entry */ | |
6666 | if (!attr->exclude_kernel) | |
6667 | mask |= PERF_SAMPLE_BRANCH_KERNEL; | |
6668 | ||
6669 | if (!attr->exclude_user) | |
6670 | mask |= PERF_SAMPLE_BRANCH_USER; | |
6671 | ||
6672 | if (!attr->exclude_hv) | |
6673 | mask |= PERF_SAMPLE_BRANCH_HV; | |
6674 | /* | |
6675 | * adjust user setting (for HW filter setup) | |
6676 | */ | |
6677 | attr->branch_sample_type = mask; | |
6678 | } | |
e712209a SE |
6679 | /* privileged levels capture (kernel, hv): check permissions */ |
6680 | if ((mask & PERF_SAMPLE_BRANCH_PERM_PLM) | |
2b923c8f SE |
6681 | && perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) |
6682 | return -EACCES; | |
bce38cd5 | 6683 | } |
4018994f | 6684 | |
c5ebcedb | 6685 | if (attr->sample_type & PERF_SAMPLE_REGS_USER) { |
4018994f | 6686 | ret = perf_reg_validate(attr->sample_regs_user); |
c5ebcedb JO |
6687 | if (ret) |
6688 | return ret; | |
6689 | } | |
6690 | ||
6691 | if (attr->sample_type & PERF_SAMPLE_STACK_USER) { | |
6692 | if (!arch_perf_have_user_stack_dump()) | |
6693 | return -ENOSYS; | |
6694 | ||
6695 | /* | |
6696 | * We have __u32 type for the size, but so far | |
6697 | * we can only use __u16 as maximum due to the | |
6698 | * __u16 sample size limit. | |
6699 | */ | |
6700 | if (attr->sample_stack_user >= USHRT_MAX) | |
6701 | ret = -EINVAL; | |
6702 | else if (!IS_ALIGNED(attr->sample_stack_user, sizeof(u64))) | |
6703 | ret = -EINVAL; | |
6704 | } | |
4018994f | 6705 | |
974802ea PZ |
6706 | out: |
6707 | return ret; | |
6708 | ||
6709 | err_size: | |
6710 | put_user(sizeof(*attr), &uattr->size); | |
6711 | ret = -E2BIG; | |
6712 | goto out; | |
6713 | } | |
6714 | ||
ac9721f3 PZ |
6715 | static int |
6716 | perf_event_set_output(struct perf_event *event, struct perf_event *output_event) | |
a4be7c27 | 6717 | { |
76369139 | 6718 | struct ring_buffer *rb = NULL, *old_rb = NULL; |
a4be7c27 PZ |
6719 | int ret = -EINVAL; |
6720 | ||
ac9721f3 | 6721 | if (!output_event) |
a4be7c27 PZ |
6722 | goto set; |
6723 | ||
ac9721f3 PZ |
6724 | /* don't allow circular references */ |
6725 | if (event == output_event) | |
a4be7c27 PZ |
6726 | goto out; |
6727 | ||
0f139300 PZ |
6728 | /* |
6729 | * Don't allow cross-cpu buffers | |
6730 | */ | |
6731 | if (output_event->cpu != event->cpu) | |
6732 | goto out; | |
6733 | ||
6734 | /* | |
76369139 | 6735 | * If its not a per-cpu rb, it must be the same task. |
0f139300 PZ |
6736 | */ |
6737 | if (output_event->cpu == -1 && output_event->ctx != event->ctx) | |
6738 | goto out; | |
6739 | ||
a4be7c27 | 6740 | set: |
cdd6c482 | 6741 | mutex_lock(&event->mmap_mutex); |
ac9721f3 PZ |
6742 | /* Can't redirect output if we've got an active mmap() */ |
6743 | if (atomic_read(&event->mmap_count)) | |
6744 | goto unlock; | |
a4be7c27 | 6745 | |
9bb5d40c PZ |
6746 | old_rb = event->rb; |
6747 | ||
ac9721f3 | 6748 | if (output_event) { |
76369139 FW |
6749 | /* get the rb we want to redirect to */ |
6750 | rb = ring_buffer_get(output_event); | |
6751 | if (!rb) | |
ac9721f3 | 6752 | goto unlock; |
a4be7c27 PZ |
6753 | } |
6754 | ||
10c6db11 PZ |
6755 | if (old_rb) |
6756 | ring_buffer_detach(event, old_rb); | |
9bb5d40c PZ |
6757 | |
6758 | if (rb) | |
6759 | ring_buffer_attach(event, rb); | |
6760 | ||
6761 | rcu_assign_pointer(event->rb, rb); | |
6762 | ||
6763 | if (old_rb) { | |
6764 | ring_buffer_put(old_rb); | |
6765 | /* | |
6766 | * Since we detached before setting the new rb, so that we | |
6767 | * could attach the new rb, we could have missed a wakeup. | |
6768 | * Provide it now. | |
6769 | */ | |
6770 | wake_up_all(&event->waitq); | |
6771 | } | |
6772 | ||
a4be7c27 | 6773 | ret = 0; |
ac9721f3 PZ |
6774 | unlock: |
6775 | mutex_unlock(&event->mmap_mutex); | |
6776 | ||
a4be7c27 | 6777 | out: |
a4be7c27 PZ |
6778 | return ret; |
6779 | } | |
6780 | ||
0793a61d | 6781 | /** |
cdd6c482 | 6782 | * sys_perf_event_open - open a performance event, associate it to a task/cpu |
9f66a381 | 6783 | * |
cdd6c482 | 6784 | * @attr_uptr: event_id type attributes for monitoring/sampling |
0793a61d | 6785 | * @pid: target pid |
9f66a381 | 6786 | * @cpu: target cpu |
cdd6c482 | 6787 | * @group_fd: group leader event fd |
0793a61d | 6788 | */ |
cdd6c482 IM |
6789 | SYSCALL_DEFINE5(perf_event_open, |
6790 | struct perf_event_attr __user *, attr_uptr, | |
2743a5b0 | 6791 | pid_t, pid, int, cpu, int, group_fd, unsigned long, flags) |
0793a61d | 6792 | { |
b04243ef PZ |
6793 | struct perf_event *group_leader = NULL, *output_event = NULL; |
6794 | struct perf_event *event, *sibling; | |
cdd6c482 IM |
6795 | struct perf_event_attr attr; |
6796 | struct perf_event_context *ctx; | |
6797 | struct file *event_file = NULL; | |
2903ff01 | 6798 | struct fd group = {NULL, 0}; |
38a81da2 | 6799 | struct task_struct *task = NULL; |
89a1e187 | 6800 | struct pmu *pmu; |
ea635c64 | 6801 | int event_fd; |
b04243ef | 6802 | int move_group = 0; |
dc86cabe | 6803 | int err; |
0793a61d | 6804 | |
2743a5b0 | 6805 | /* for future expandability... */ |
e5d1367f | 6806 | if (flags & ~PERF_FLAG_ALL) |
2743a5b0 PM |
6807 | return -EINVAL; |
6808 | ||
dc86cabe IM |
6809 | err = perf_copy_attr(attr_uptr, &attr); |
6810 | if (err) | |
6811 | return err; | |
eab656ae | 6812 | |
0764771d PZ |
6813 | if (!attr.exclude_kernel) { |
6814 | if (perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) | |
6815 | return -EACCES; | |
6816 | } | |
6817 | ||
df58ab24 | 6818 | if (attr.freq) { |
cdd6c482 | 6819 | if (attr.sample_freq > sysctl_perf_event_sample_rate) |
df58ab24 PZ |
6820 | return -EINVAL; |
6821 | } | |
6822 | ||
e5d1367f SE |
6823 | /* |
6824 | * In cgroup mode, the pid argument is used to pass the fd | |
6825 | * opened to the cgroup directory in cgroupfs. The cpu argument | |
6826 | * designates the cpu on which to monitor threads from that | |
6827 | * cgroup. | |
6828 | */ | |
6829 | if ((flags & PERF_FLAG_PID_CGROUP) && (pid == -1 || cpu == -1)) | |
6830 | return -EINVAL; | |
6831 | ||
ab72a702 | 6832 | event_fd = get_unused_fd(); |
ea635c64 AV |
6833 | if (event_fd < 0) |
6834 | return event_fd; | |
6835 | ||
ac9721f3 | 6836 | if (group_fd != -1) { |
2903ff01 AV |
6837 | err = perf_fget_light(group_fd, &group); |
6838 | if (err) | |
d14b12d7 | 6839 | goto err_fd; |
2903ff01 | 6840 | group_leader = group.file->private_data; |
ac9721f3 PZ |
6841 | if (flags & PERF_FLAG_FD_OUTPUT) |
6842 | output_event = group_leader; | |
6843 | if (flags & PERF_FLAG_FD_NO_GROUP) | |
6844 | group_leader = NULL; | |
6845 | } | |
6846 | ||
e5d1367f | 6847 | if (pid != -1 && !(flags & PERF_FLAG_PID_CGROUP)) { |
c6be5a5c PZ |
6848 | task = find_lively_task_by_vpid(pid); |
6849 | if (IS_ERR(task)) { | |
6850 | err = PTR_ERR(task); | |
6851 | goto err_group_fd; | |
6852 | } | |
6853 | } | |
6854 | ||
fbfc623f YZ |
6855 | get_online_cpus(); |
6856 | ||
4dc0da86 AK |
6857 | event = perf_event_alloc(&attr, cpu, task, group_leader, NULL, |
6858 | NULL, NULL); | |
d14b12d7 SE |
6859 | if (IS_ERR(event)) { |
6860 | err = PTR_ERR(event); | |
c6be5a5c | 6861 | goto err_task; |
d14b12d7 SE |
6862 | } |
6863 | ||
e5d1367f SE |
6864 | if (flags & PERF_FLAG_PID_CGROUP) { |
6865 | err = perf_cgroup_connect(pid, event, &attr, group_leader); | |
6866 | if (err) | |
6867 | goto err_alloc; | |
08309379 PZ |
6868 | /* |
6869 | * one more event: | |
6870 | * - that has cgroup constraint on event->cpu | |
6871 | * - that may need work on context switch | |
6872 | */ | |
6873 | atomic_inc(&per_cpu(perf_cgroup_events, event->cpu)); | |
c5905afb | 6874 | static_key_slow_inc(&perf_sched_events.key); |
e5d1367f SE |
6875 | } |
6876 | ||
89a1e187 PZ |
6877 | /* |
6878 | * Special case software events and allow them to be part of | |
6879 | * any hardware group. | |
6880 | */ | |
6881 | pmu = event->pmu; | |
b04243ef PZ |
6882 | |
6883 | if (group_leader && | |
6884 | (is_software_event(event) != is_software_event(group_leader))) { | |
6885 | if (is_software_event(event)) { | |
6886 | /* | |
6887 | * If event and group_leader are not both a software | |
6888 | * event, and event is, then group leader is not. | |
6889 | * | |
6890 | * Allow the addition of software events to !software | |
6891 | * groups, this is safe because software events never | |
6892 | * fail to schedule. | |
6893 | */ | |
6894 | pmu = group_leader->pmu; | |
6895 | } else if (is_software_event(group_leader) && | |
6896 | (group_leader->group_flags & PERF_GROUP_SOFTWARE)) { | |
6897 | /* | |
6898 | * In case the group is a pure software group, and we | |
6899 | * try to add a hardware event, move the whole group to | |
6900 | * the hardware context. | |
6901 | */ | |
6902 | move_group = 1; | |
6903 | } | |
6904 | } | |
89a1e187 PZ |
6905 | |
6906 | /* | |
6907 | * Get the target context (task or percpu): | |
6908 | */ | |
e2d37cd2 | 6909 | ctx = find_get_context(pmu, task, event->cpu); |
89a1e187 PZ |
6910 | if (IS_ERR(ctx)) { |
6911 | err = PTR_ERR(ctx); | |
c6be5a5c | 6912 | goto err_alloc; |
89a1e187 PZ |
6913 | } |
6914 | ||
fd1edb3a PZ |
6915 | if (task) { |
6916 | put_task_struct(task); | |
6917 | task = NULL; | |
6918 | } | |
6919 | ||
ccff286d | 6920 | /* |
cdd6c482 | 6921 | * Look up the group leader (we will attach this event to it): |
04289bb9 | 6922 | */ |
ac9721f3 | 6923 | if (group_leader) { |
dc86cabe | 6924 | err = -EINVAL; |
04289bb9 | 6925 | |
04289bb9 | 6926 | /* |
ccff286d IM |
6927 | * Do not allow a recursive hierarchy (this new sibling |
6928 | * becoming part of another group-sibling): | |
6929 | */ | |
6930 | if (group_leader->group_leader != group_leader) | |
c3f00c70 | 6931 | goto err_context; |
ccff286d IM |
6932 | /* |
6933 | * Do not allow to attach to a group in a different | |
6934 | * task or CPU context: | |
04289bb9 | 6935 | */ |
b04243ef PZ |
6936 | if (move_group) { |
6937 | if (group_leader->ctx->type != ctx->type) | |
6938 | goto err_context; | |
6939 | } else { | |
6940 | if (group_leader->ctx != ctx) | |
6941 | goto err_context; | |
6942 | } | |
6943 | ||
3b6f9e5c PM |
6944 | /* |
6945 | * Only a group leader can be exclusive or pinned | |
6946 | */ | |
0d48696f | 6947 | if (attr.exclusive || attr.pinned) |
c3f00c70 | 6948 | goto err_context; |
ac9721f3 PZ |
6949 | } |
6950 | ||
6951 | if (output_event) { | |
6952 | err = perf_event_set_output(event, output_event); | |
6953 | if (err) | |
c3f00c70 | 6954 | goto err_context; |
ac9721f3 | 6955 | } |
0793a61d | 6956 | |
ea635c64 AV |
6957 | event_file = anon_inode_getfile("[perf_event]", &perf_fops, event, O_RDWR); |
6958 | if (IS_ERR(event_file)) { | |
6959 | err = PTR_ERR(event_file); | |
c3f00c70 | 6960 | goto err_context; |
ea635c64 | 6961 | } |
9b51f66d | 6962 | |
b04243ef PZ |
6963 | if (move_group) { |
6964 | struct perf_event_context *gctx = group_leader->ctx; | |
6965 | ||
6966 | mutex_lock(&gctx->mutex); | |
fe4b04fa | 6967 | perf_remove_from_context(group_leader); |
0231bb53 JO |
6968 | |
6969 | /* | |
6970 | * Removing from the context ends up with disabled | |
6971 | * event. What we want here is event in the initial | |
6972 | * startup state, ready to be add into new context. | |
6973 | */ | |
6974 | perf_event__state_init(group_leader); | |
b04243ef PZ |
6975 | list_for_each_entry(sibling, &group_leader->sibling_list, |
6976 | group_entry) { | |
fe4b04fa | 6977 | perf_remove_from_context(sibling); |
0231bb53 | 6978 | perf_event__state_init(sibling); |
b04243ef PZ |
6979 | put_ctx(gctx); |
6980 | } | |
6981 | mutex_unlock(&gctx->mutex); | |
6982 | put_ctx(gctx); | |
ea635c64 | 6983 | } |
9b51f66d | 6984 | |
ad3a37de | 6985 | WARN_ON_ONCE(ctx->parent_ctx); |
d859e29f | 6986 | mutex_lock(&ctx->mutex); |
b04243ef PZ |
6987 | |
6988 | if (move_group) { | |
0cda4c02 | 6989 | synchronize_rcu(); |
e2d37cd2 | 6990 | perf_install_in_context(ctx, group_leader, event->cpu); |
b04243ef PZ |
6991 | get_ctx(ctx); |
6992 | list_for_each_entry(sibling, &group_leader->sibling_list, | |
6993 | group_entry) { | |
e2d37cd2 | 6994 | perf_install_in_context(ctx, sibling, event->cpu); |
b04243ef PZ |
6995 | get_ctx(ctx); |
6996 | } | |
6997 | } | |
6998 | ||
e2d37cd2 | 6999 | perf_install_in_context(ctx, event, event->cpu); |
ad3a37de | 7000 | ++ctx->generation; |
fe4b04fa | 7001 | perf_unpin_context(ctx); |
d859e29f | 7002 | mutex_unlock(&ctx->mutex); |
9b51f66d | 7003 | |
fbfc623f YZ |
7004 | put_online_cpus(); |
7005 | ||
cdd6c482 | 7006 | event->owner = current; |
8882135b | 7007 | |
cdd6c482 IM |
7008 | mutex_lock(¤t->perf_event_mutex); |
7009 | list_add_tail(&event->owner_entry, ¤t->perf_event_list); | |
7010 | mutex_unlock(¤t->perf_event_mutex); | |
082ff5a2 | 7011 | |
c320c7b7 ACM |
7012 | /* |
7013 | * Precalculate sample_data sizes | |
7014 | */ | |
7015 | perf_event__header_size(event); | |
6844c09d | 7016 | perf_event__id_header_size(event); |
c320c7b7 | 7017 | |
8a49542c PZ |
7018 | /* |
7019 | * Drop the reference on the group_event after placing the | |
7020 | * new event on the sibling_list. This ensures destruction | |
7021 | * of the group leader will find the pointer to itself in | |
7022 | * perf_group_detach(). | |
7023 | */ | |
2903ff01 | 7024 | fdput(group); |
ea635c64 AV |
7025 | fd_install(event_fd, event_file); |
7026 | return event_fd; | |
0793a61d | 7027 | |
c3f00c70 | 7028 | err_context: |
fe4b04fa | 7029 | perf_unpin_context(ctx); |
ea635c64 | 7030 | put_ctx(ctx); |
c6be5a5c | 7031 | err_alloc: |
ea635c64 | 7032 | free_event(event); |
e7d0bc04 | 7033 | err_task: |
fbfc623f | 7034 | put_online_cpus(); |
e7d0bc04 PZ |
7035 | if (task) |
7036 | put_task_struct(task); | |
89a1e187 | 7037 | err_group_fd: |
2903ff01 | 7038 | fdput(group); |
ea635c64 AV |
7039 | err_fd: |
7040 | put_unused_fd(event_fd); | |
dc86cabe | 7041 | return err; |
0793a61d TG |
7042 | } |
7043 | ||
fb0459d7 AV |
7044 | /** |
7045 | * perf_event_create_kernel_counter | |
7046 | * | |
7047 | * @attr: attributes of the counter to create | |
7048 | * @cpu: cpu in which the counter is bound | |
38a81da2 | 7049 | * @task: task to profile (NULL for percpu) |
fb0459d7 AV |
7050 | */ |
7051 | struct perf_event * | |
7052 | perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, | |
38a81da2 | 7053 | struct task_struct *task, |
4dc0da86 AK |
7054 | perf_overflow_handler_t overflow_handler, |
7055 | void *context) | |
fb0459d7 | 7056 | { |
fb0459d7 | 7057 | struct perf_event_context *ctx; |
c3f00c70 | 7058 | struct perf_event *event; |
fb0459d7 | 7059 | int err; |
d859e29f | 7060 | |
fb0459d7 AV |
7061 | /* |
7062 | * Get the target context (task or percpu): | |
7063 | */ | |
d859e29f | 7064 | |
4dc0da86 AK |
7065 | event = perf_event_alloc(attr, cpu, task, NULL, NULL, |
7066 | overflow_handler, context); | |
c3f00c70 PZ |
7067 | if (IS_ERR(event)) { |
7068 | err = PTR_ERR(event); | |
7069 | goto err; | |
7070 | } | |
d859e29f | 7071 | |
38a81da2 | 7072 | ctx = find_get_context(event->pmu, task, cpu); |
c6567f64 FW |
7073 | if (IS_ERR(ctx)) { |
7074 | err = PTR_ERR(ctx); | |
c3f00c70 | 7075 | goto err_free; |
d859e29f | 7076 | } |
fb0459d7 | 7077 | |
fb0459d7 AV |
7078 | WARN_ON_ONCE(ctx->parent_ctx); |
7079 | mutex_lock(&ctx->mutex); | |
7080 | perf_install_in_context(ctx, event, cpu); | |
7081 | ++ctx->generation; | |
fe4b04fa | 7082 | perf_unpin_context(ctx); |
fb0459d7 AV |
7083 | mutex_unlock(&ctx->mutex); |
7084 | ||
fb0459d7 AV |
7085 | return event; |
7086 | ||
c3f00c70 PZ |
7087 | err_free: |
7088 | free_event(event); | |
7089 | err: | |
c6567f64 | 7090 | return ERR_PTR(err); |
9b51f66d | 7091 | } |
fb0459d7 | 7092 | EXPORT_SYMBOL_GPL(perf_event_create_kernel_counter); |
9b51f66d | 7093 | |
0cda4c02 YZ |
7094 | void perf_pmu_migrate_context(struct pmu *pmu, int src_cpu, int dst_cpu) |
7095 | { | |
7096 | struct perf_event_context *src_ctx; | |
7097 | struct perf_event_context *dst_ctx; | |
7098 | struct perf_event *event, *tmp; | |
7099 | LIST_HEAD(events); | |
7100 | ||
7101 | src_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, src_cpu)->ctx; | |
7102 | dst_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, dst_cpu)->ctx; | |
7103 | ||
7104 | mutex_lock(&src_ctx->mutex); | |
7105 | list_for_each_entry_safe(event, tmp, &src_ctx->event_list, | |
7106 | event_entry) { | |
7107 | perf_remove_from_context(event); | |
7108 | put_ctx(src_ctx); | |
7109 | list_add(&event->event_entry, &events); | |
7110 | } | |
7111 | mutex_unlock(&src_ctx->mutex); | |
7112 | ||
7113 | synchronize_rcu(); | |
7114 | ||
7115 | mutex_lock(&dst_ctx->mutex); | |
7116 | list_for_each_entry_safe(event, tmp, &events, event_entry) { | |
7117 | list_del(&event->event_entry); | |
7118 | if (event->state >= PERF_EVENT_STATE_OFF) | |
7119 | event->state = PERF_EVENT_STATE_INACTIVE; | |
7120 | perf_install_in_context(dst_ctx, event, dst_cpu); | |
7121 | get_ctx(dst_ctx); | |
7122 | } | |
7123 | mutex_unlock(&dst_ctx->mutex); | |
7124 | } | |
7125 | EXPORT_SYMBOL_GPL(perf_pmu_migrate_context); | |
7126 | ||
cdd6c482 | 7127 | static void sync_child_event(struct perf_event *child_event, |
38b200d6 | 7128 | struct task_struct *child) |
d859e29f | 7129 | { |
cdd6c482 | 7130 | struct perf_event *parent_event = child_event->parent; |
8bc20959 | 7131 | u64 child_val; |
d859e29f | 7132 | |
cdd6c482 IM |
7133 | if (child_event->attr.inherit_stat) |
7134 | perf_event_read_event(child_event, child); | |
38b200d6 | 7135 | |
b5e58793 | 7136 | child_val = perf_event_count(child_event); |
d859e29f PM |
7137 | |
7138 | /* | |
7139 | * Add back the child's count to the parent's count: | |
7140 | */ | |
a6e6dea6 | 7141 | atomic64_add(child_val, &parent_event->child_count); |
cdd6c482 IM |
7142 | atomic64_add(child_event->total_time_enabled, |
7143 | &parent_event->child_total_time_enabled); | |
7144 | atomic64_add(child_event->total_time_running, | |
7145 | &parent_event->child_total_time_running); | |
d859e29f PM |
7146 | |
7147 | /* | |
cdd6c482 | 7148 | * Remove this event from the parent's list |
d859e29f | 7149 | */ |
cdd6c482 IM |
7150 | WARN_ON_ONCE(parent_event->ctx->parent_ctx); |
7151 | mutex_lock(&parent_event->child_mutex); | |
7152 | list_del_init(&child_event->child_list); | |
7153 | mutex_unlock(&parent_event->child_mutex); | |
d859e29f PM |
7154 | |
7155 | /* | |
cdd6c482 | 7156 | * Release the parent event, if this was the last |
d859e29f PM |
7157 | * reference to it. |
7158 | */ | |
a6fa941d | 7159 | put_event(parent_event); |
d859e29f PM |
7160 | } |
7161 | ||
9b51f66d | 7162 | static void |
cdd6c482 IM |
7163 | __perf_event_exit_task(struct perf_event *child_event, |
7164 | struct perf_event_context *child_ctx, | |
38b200d6 | 7165 | struct task_struct *child) |
9b51f66d | 7166 | { |
38b435b1 PZ |
7167 | if (child_event->parent) { |
7168 | raw_spin_lock_irq(&child_ctx->lock); | |
7169 | perf_group_detach(child_event); | |
7170 | raw_spin_unlock_irq(&child_ctx->lock); | |
7171 | } | |
9b51f66d | 7172 | |
fe4b04fa | 7173 | perf_remove_from_context(child_event); |
0cc0c027 | 7174 | |
9b51f66d | 7175 | /* |
38b435b1 | 7176 | * It can happen that the parent exits first, and has events |
9b51f66d | 7177 | * that are still around due to the child reference. These |
38b435b1 | 7178 | * events need to be zapped. |
9b51f66d | 7179 | */ |
38b435b1 | 7180 | if (child_event->parent) { |
cdd6c482 IM |
7181 | sync_child_event(child_event, child); |
7182 | free_event(child_event); | |
4bcf349a | 7183 | } |
9b51f66d IM |
7184 | } |
7185 | ||
8dc85d54 | 7186 | static void perf_event_exit_task_context(struct task_struct *child, int ctxn) |
9b51f66d | 7187 | { |
cdd6c482 IM |
7188 | struct perf_event *child_event, *tmp; |
7189 | struct perf_event_context *child_ctx; | |
a63eaf34 | 7190 | unsigned long flags; |
9b51f66d | 7191 | |
8dc85d54 | 7192 | if (likely(!child->perf_event_ctxp[ctxn])) { |
cdd6c482 | 7193 | perf_event_task(child, NULL, 0); |
9b51f66d | 7194 | return; |
9f498cc5 | 7195 | } |
9b51f66d | 7196 | |
a63eaf34 | 7197 | local_irq_save(flags); |
ad3a37de PM |
7198 | /* |
7199 | * We can't reschedule here because interrupts are disabled, | |
7200 | * and either child is current or it is a task that can't be | |
7201 | * scheduled, so we are now safe from rescheduling changing | |
7202 | * our context. | |
7203 | */ | |
806839b2 | 7204 | child_ctx = rcu_dereference_raw(child->perf_event_ctxp[ctxn]); |
c93f7669 PM |
7205 | |
7206 | /* | |
7207 | * Take the context lock here so that if find_get_context is | |
cdd6c482 | 7208 | * reading child->perf_event_ctxp, we wait until it has |
c93f7669 PM |
7209 | * incremented the context's refcount before we do put_ctx below. |
7210 | */ | |
e625cce1 | 7211 | raw_spin_lock(&child_ctx->lock); |
04dc2dbb | 7212 | task_ctx_sched_out(child_ctx); |
8dc85d54 | 7213 | child->perf_event_ctxp[ctxn] = NULL; |
71a851b4 PZ |
7214 | /* |
7215 | * If this context is a clone; unclone it so it can't get | |
7216 | * swapped to another process while we're removing all | |
cdd6c482 | 7217 | * the events from it. |
71a851b4 PZ |
7218 | */ |
7219 | unclone_ctx(child_ctx); | |
5e942bb3 | 7220 | update_context_time(child_ctx); |
e625cce1 | 7221 | raw_spin_unlock_irqrestore(&child_ctx->lock, flags); |
9f498cc5 PZ |
7222 | |
7223 | /* | |
cdd6c482 IM |
7224 | * Report the task dead after unscheduling the events so that we |
7225 | * won't get any samples after PERF_RECORD_EXIT. We can however still | |
7226 | * get a few PERF_RECORD_READ events. | |
9f498cc5 | 7227 | */ |
cdd6c482 | 7228 | perf_event_task(child, child_ctx, 0); |
a63eaf34 | 7229 | |
66fff224 PZ |
7230 | /* |
7231 | * We can recurse on the same lock type through: | |
7232 | * | |
cdd6c482 IM |
7233 | * __perf_event_exit_task() |
7234 | * sync_child_event() | |
a6fa941d AV |
7235 | * put_event() |
7236 | * mutex_lock(&ctx->mutex) | |
66fff224 PZ |
7237 | * |
7238 | * But since its the parent context it won't be the same instance. | |
7239 | */ | |
a0507c84 | 7240 | mutex_lock(&child_ctx->mutex); |
a63eaf34 | 7241 | |
8bc20959 | 7242 | again: |
889ff015 FW |
7243 | list_for_each_entry_safe(child_event, tmp, &child_ctx->pinned_groups, |
7244 | group_entry) | |
7245 | __perf_event_exit_task(child_event, child_ctx, child); | |
7246 | ||
7247 | list_for_each_entry_safe(child_event, tmp, &child_ctx->flexible_groups, | |
65abc865 | 7248 | group_entry) |
cdd6c482 | 7249 | __perf_event_exit_task(child_event, child_ctx, child); |
8bc20959 PZ |
7250 | |
7251 | /* | |
cdd6c482 | 7252 | * If the last event was a group event, it will have appended all |
8bc20959 PZ |
7253 | * its siblings to the list, but we obtained 'tmp' before that which |
7254 | * will still point to the list head terminating the iteration. | |
7255 | */ | |
889ff015 FW |
7256 | if (!list_empty(&child_ctx->pinned_groups) || |
7257 | !list_empty(&child_ctx->flexible_groups)) | |
8bc20959 | 7258 | goto again; |
a63eaf34 PM |
7259 | |
7260 | mutex_unlock(&child_ctx->mutex); | |
7261 | ||
7262 | put_ctx(child_ctx); | |
9b51f66d IM |
7263 | } |
7264 | ||
8dc85d54 PZ |
7265 | /* |
7266 | * When a child task exits, feed back event values to parent events. | |
7267 | */ | |
7268 | void perf_event_exit_task(struct task_struct *child) | |
7269 | { | |
8882135b | 7270 | struct perf_event *event, *tmp; |
8dc85d54 PZ |
7271 | int ctxn; |
7272 | ||
8882135b PZ |
7273 | mutex_lock(&child->perf_event_mutex); |
7274 | list_for_each_entry_safe(event, tmp, &child->perf_event_list, | |
7275 | owner_entry) { | |
7276 | list_del_init(&event->owner_entry); | |
7277 | ||
7278 | /* | |
7279 | * Ensure the list deletion is visible before we clear | |
7280 | * the owner, closes a race against perf_release() where | |
7281 | * we need to serialize on the owner->perf_event_mutex. | |
7282 | */ | |
7283 | smp_wmb(); | |
7284 | event->owner = NULL; | |
7285 | } | |
7286 | mutex_unlock(&child->perf_event_mutex); | |
7287 | ||
8dc85d54 PZ |
7288 | for_each_task_context_nr(ctxn) |
7289 | perf_event_exit_task_context(child, ctxn); | |
7290 | } | |
7291 | ||
889ff015 FW |
7292 | static void perf_free_event(struct perf_event *event, |
7293 | struct perf_event_context *ctx) | |
7294 | { | |
7295 | struct perf_event *parent = event->parent; | |
7296 | ||
7297 | if (WARN_ON_ONCE(!parent)) | |
7298 | return; | |
7299 | ||
7300 | mutex_lock(&parent->child_mutex); | |
7301 | list_del_init(&event->child_list); | |
7302 | mutex_unlock(&parent->child_mutex); | |
7303 | ||
a6fa941d | 7304 | put_event(parent); |
889ff015 | 7305 | |
8a49542c | 7306 | perf_group_detach(event); |
889ff015 FW |
7307 | list_del_event(event, ctx); |
7308 | free_event(event); | |
7309 | } | |
7310 | ||
bbbee908 PZ |
7311 | /* |
7312 | * free an unexposed, unused context as created by inheritance by | |
8dc85d54 | 7313 | * perf_event_init_task below, used by fork() in case of fail. |
bbbee908 | 7314 | */ |
cdd6c482 | 7315 | void perf_event_free_task(struct task_struct *task) |
bbbee908 | 7316 | { |
8dc85d54 | 7317 | struct perf_event_context *ctx; |
cdd6c482 | 7318 | struct perf_event *event, *tmp; |
8dc85d54 | 7319 | int ctxn; |
bbbee908 | 7320 | |
8dc85d54 PZ |
7321 | for_each_task_context_nr(ctxn) { |
7322 | ctx = task->perf_event_ctxp[ctxn]; | |
7323 | if (!ctx) | |
7324 | continue; | |
bbbee908 | 7325 | |
8dc85d54 | 7326 | mutex_lock(&ctx->mutex); |
bbbee908 | 7327 | again: |
8dc85d54 PZ |
7328 | list_for_each_entry_safe(event, tmp, &ctx->pinned_groups, |
7329 | group_entry) | |
7330 | perf_free_event(event, ctx); | |
bbbee908 | 7331 | |
8dc85d54 PZ |
7332 | list_for_each_entry_safe(event, tmp, &ctx->flexible_groups, |
7333 | group_entry) | |
7334 | perf_free_event(event, ctx); | |
bbbee908 | 7335 | |
8dc85d54 PZ |
7336 | if (!list_empty(&ctx->pinned_groups) || |
7337 | !list_empty(&ctx->flexible_groups)) | |
7338 | goto again; | |
bbbee908 | 7339 | |
8dc85d54 | 7340 | mutex_unlock(&ctx->mutex); |
bbbee908 | 7341 | |
8dc85d54 PZ |
7342 | put_ctx(ctx); |
7343 | } | |
889ff015 FW |
7344 | } |
7345 | ||
4e231c79 PZ |
7346 | void perf_event_delayed_put(struct task_struct *task) |
7347 | { | |
7348 | int ctxn; | |
7349 | ||
7350 | for_each_task_context_nr(ctxn) | |
7351 | WARN_ON_ONCE(task->perf_event_ctxp[ctxn]); | |
7352 | } | |
7353 | ||
97dee4f3 PZ |
7354 | /* |
7355 | * inherit a event from parent task to child task: | |
7356 | */ | |
7357 | static struct perf_event * | |
7358 | inherit_event(struct perf_event *parent_event, | |
7359 | struct task_struct *parent, | |
7360 | struct perf_event_context *parent_ctx, | |
7361 | struct task_struct *child, | |
7362 | struct perf_event *group_leader, | |
7363 | struct perf_event_context *child_ctx) | |
7364 | { | |
7365 | struct perf_event *child_event; | |
cee010ec | 7366 | unsigned long flags; |
97dee4f3 PZ |
7367 | |
7368 | /* | |
7369 | * Instead of creating recursive hierarchies of events, | |
7370 | * we link inherited events back to the original parent, | |
7371 | * which has a filp for sure, which we use as the reference | |
7372 | * count: | |
7373 | */ | |
7374 | if (parent_event->parent) | |
7375 | parent_event = parent_event->parent; | |
7376 | ||
7377 | child_event = perf_event_alloc(&parent_event->attr, | |
7378 | parent_event->cpu, | |
d580ff86 | 7379 | child, |
97dee4f3 | 7380 | group_leader, parent_event, |
4dc0da86 | 7381 | NULL, NULL); |
97dee4f3 PZ |
7382 | if (IS_ERR(child_event)) |
7383 | return child_event; | |
a6fa941d AV |
7384 | |
7385 | if (!atomic_long_inc_not_zero(&parent_event->refcount)) { | |
7386 | free_event(child_event); | |
7387 | return NULL; | |
7388 | } | |
7389 | ||
97dee4f3 PZ |
7390 | get_ctx(child_ctx); |
7391 | ||
7392 | /* | |
7393 | * Make the child state follow the state of the parent event, | |
7394 | * not its attr.disabled bit. We hold the parent's mutex, | |
7395 | * so we won't race with perf_event_{en, dis}able_family. | |
7396 | */ | |
7397 | if (parent_event->state >= PERF_EVENT_STATE_INACTIVE) | |
7398 | child_event->state = PERF_EVENT_STATE_INACTIVE; | |
7399 | else | |
7400 | child_event->state = PERF_EVENT_STATE_OFF; | |
7401 | ||
7402 | if (parent_event->attr.freq) { | |
7403 | u64 sample_period = parent_event->hw.sample_period; | |
7404 | struct hw_perf_event *hwc = &child_event->hw; | |
7405 | ||
7406 | hwc->sample_period = sample_period; | |
7407 | hwc->last_period = sample_period; | |
7408 | ||
7409 | local64_set(&hwc->period_left, sample_period); | |
7410 | } | |
7411 | ||
7412 | child_event->ctx = child_ctx; | |
7413 | child_event->overflow_handler = parent_event->overflow_handler; | |
4dc0da86 AK |
7414 | child_event->overflow_handler_context |
7415 | = parent_event->overflow_handler_context; | |
97dee4f3 | 7416 | |
614b6780 TG |
7417 | /* |
7418 | * Precalculate sample_data sizes | |
7419 | */ | |
7420 | perf_event__header_size(child_event); | |
6844c09d | 7421 | perf_event__id_header_size(child_event); |
614b6780 | 7422 | |
97dee4f3 PZ |
7423 | /* |
7424 | * Link it up in the child's context: | |
7425 | */ | |
cee010ec | 7426 | raw_spin_lock_irqsave(&child_ctx->lock, flags); |
97dee4f3 | 7427 | add_event_to_ctx(child_event, child_ctx); |
cee010ec | 7428 | raw_spin_unlock_irqrestore(&child_ctx->lock, flags); |
97dee4f3 | 7429 | |
97dee4f3 PZ |
7430 | /* |
7431 | * Link this into the parent event's child list | |
7432 | */ | |
7433 | WARN_ON_ONCE(parent_event->ctx->parent_ctx); | |
7434 | mutex_lock(&parent_event->child_mutex); | |
7435 | list_add_tail(&child_event->child_list, &parent_event->child_list); | |
7436 | mutex_unlock(&parent_event->child_mutex); | |
7437 | ||
7438 | return child_event; | |
7439 | } | |
7440 | ||
7441 | static int inherit_group(struct perf_event *parent_event, | |
7442 | struct task_struct *parent, | |
7443 | struct perf_event_context *parent_ctx, | |
7444 | struct task_struct *child, | |
7445 | struct perf_event_context *child_ctx) | |
7446 | { | |
7447 | struct perf_event *leader; | |
7448 | struct perf_event *sub; | |
7449 | struct perf_event *child_ctr; | |
7450 | ||
7451 | leader = inherit_event(parent_event, parent, parent_ctx, | |
7452 | child, NULL, child_ctx); | |
7453 | if (IS_ERR(leader)) | |
7454 | return PTR_ERR(leader); | |
7455 | list_for_each_entry(sub, &parent_event->sibling_list, group_entry) { | |
7456 | child_ctr = inherit_event(sub, parent, parent_ctx, | |
7457 | child, leader, child_ctx); | |
7458 | if (IS_ERR(child_ctr)) | |
7459 | return PTR_ERR(child_ctr); | |
7460 | } | |
7461 | return 0; | |
889ff015 FW |
7462 | } |
7463 | ||
7464 | static int | |
7465 | inherit_task_group(struct perf_event *event, struct task_struct *parent, | |
7466 | struct perf_event_context *parent_ctx, | |
8dc85d54 | 7467 | struct task_struct *child, int ctxn, |
889ff015 FW |
7468 | int *inherited_all) |
7469 | { | |
7470 | int ret; | |
8dc85d54 | 7471 | struct perf_event_context *child_ctx; |
889ff015 FW |
7472 | |
7473 | if (!event->attr.inherit) { | |
7474 | *inherited_all = 0; | |
7475 | return 0; | |
bbbee908 PZ |
7476 | } |
7477 | ||
fe4b04fa | 7478 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 FW |
7479 | if (!child_ctx) { |
7480 | /* | |
7481 | * This is executed from the parent task context, so | |
7482 | * inherit events that have been marked for cloning. | |
7483 | * First allocate and initialize a context for the | |
7484 | * child. | |
7485 | */ | |
bbbee908 | 7486 | |
734df5ab | 7487 | child_ctx = alloc_perf_context(parent_ctx->pmu, child); |
889ff015 FW |
7488 | if (!child_ctx) |
7489 | return -ENOMEM; | |
bbbee908 | 7490 | |
8dc85d54 | 7491 | child->perf_event_ctxp[ctxn] = child_ctx; |
889ff015 FW |
7492 | } |
7493 | ||
7494 | ret = inherit_group(event, parent, parent_ctx, | |
7495 | child, child_ctx); | |
7496 | ||
7497 | if (ret) | |
7498 | *inherited_all = 0; | |
7499 | ||
7500 | return ret; | |
bbbee908 PZ |
7501 | } |
7502 | ||
9b51f66d | 7503 | /* |
cdd6c482 | 7504 | * Initialize the perf_event context in task_struct |
9b51f66d | 7505 | */ |
8dc85d54 | 7506 | int perf_event_init_context(struct task_struct *child, int ctxn) |
9b51f66d | 7507 | { |
889ff015 | 7508 | struct perf_event_context *child_ctx, *parent_ctx; |
cdd6c482 IM |
7509 | struct perf_event_context *cloned_ctx; |
7510 | struct perf_event *event; | |
9b51f66d | 7511 | struct task_struct *parent = current; |
564c2b21 | 7512 | int inherited_all = 1; |
dddd3379 | 7513 | unsigned long flags; |
6ab423e0 | 7514 | int ret = 0; |
9b51f66d | 7515 | |
8dc85d54 | 7516 | if (likely(!parent->perf_event_ctxp[ctxn])) |
6ab423e0 PZ |
7517 | return 0; |
7518 | ||
ad3a37de | 7519 | /* |
25346b93 PM |
7520 | * If the parent's context is a clone, pin it so it won't get |
7521 | * swapped under us. | |
ad3a37de | 7522 | */ |
8dc85d54 | 7523 | parent_ctx = perf_pin_task_context(parent, ctxn); |
25346b93 | 7524 | |
ad3a37de PM |
7525 | /* |
7526 | * No need to check if parent_ctx != NULL here; since we saw | |
7527 | * it non-NULL earlier, the only reason for it to become NULL | |
7528 | * is if we exit, and since we're currently in the middle of | |
7529 | * a fork we can't be exiting at the same time. | |
7530 | */ | |
ad3a37de | 7531 | |
9b51f66d IM |
7532 | /* |
7533 | * Lock the parent list. No need to lock the child - not PID | |
7534 | * hashed yet and not running, so nobody can access it. | |
7535 | */ | |
d859e29f | 7536 | mutex_lock(&parent_ctx->mutex); |
9b51f66d IM |
7537 | |
7538 | /* | |
7539 | * We dont have to disable NMIs - we are only looking at | |
7540 | * the list, not manipulating it: | |
7541 | */ | |
889ff015 | 7542 | list_for_each_entry(event, &parent_ctx->pinned_groups, group_entry) { |
8dc85d54 PZ |
7543 | ret = inherit_task_group(event, parent, parent_ctx, |
7544 | child, ctxn, &inherited_all); | |
889ff015 FW |
7545 | if (ret) |
7546 | break; | |
7547 | } | |
b93f7978 | 7548 | |
dddd3379 TG |
7549 | /* |
7550 | * We can't hold ctx->lock when iterating the ->flexible_group list due | |
7551 | * to allocations, but we need to prevent rotation because | |
7552 | * rotate_ctx() will change the list from interrupt context. | |
7553 | */ | |
7554 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); | |
7555 | parent_ctx->rotate_disable = 1; | |
7556 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); | |
7557 | ||
889ff015 | 7558 | list_for_each_entry(event, &parent_ctx->flexible_groups, group_entry) { |
8dc85d54 PZ |
7559 | ret = inherit_task_group(event, parent, parent_ctx, |
7560 | child, ctxn, &inherited_all); | |
889ff015 | 7561 | if (ret) |
9b51f66d | 7562 | break; |
564c2b21 PM |
7563 | } |
7564 | ||
dddd3379 TG |
7565 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); |
7566 | parent_ctx->rotate_disable = 0; | |
dddd3379 | 7567 | |
8dc85d54 | 7568 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 | 7569 | |
05cbaa28 | 7570 | if (child_ctx && inherited_all) { |
564c2b21 PM |
7571 | /* |
7572 | * Mark the child context as a clone of the parent | |
7573 | * context, or of whatever the parent is a clone of. | |
c5ed5145 PZ |
7574 | * |
7575 | * Note that if the parent is a clone, the holding of | |
7576 | * parent_ctx->lock avoids it from being uncloned. | |
564c2b21 | 7577 | */ |
c5ed5145 | 7578 | cloned_ctx = parent_ctx->parent_ctx; |
ad3a37de PM |
7579 | if (cloned_ctx) { |
7580 | child_ctx->parent_ctx = cloned_ctx; | |
25346b93 | 7581 | child_ctx->parent_gen = parent_ctx->parent_gen; |
564c2b21 PM |
7582 | } else { |
7583 | child_ctx->parent_ctx = parent_ctx; | |
7584 | child_ctx->parent_gen = parent_ctx->generation; | |
7585 | } | |
7586 | get_ctx(child_ctx->parent_ctx); | |
9b51f66d IM |
7587 | } |
7588 | ||
c5ed5145 | 7589 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); |
d859e29f | 7590 | mutex_unlock(&parent_ctx->mutex); |
6ab423e0 | 7591 | |
25346b93 | 7592 | perf_unpin_context(parent_ctx); |
fe4b04fa | 7593 | put_ctx(parent_ctx); |
ad3a37de | 7594 | |
6ab423e0 | 7595 | return ret; |
9b51f66d IM |
7596 | } |
7597 | ||
8dc85d54 PZ |
7598 | /* |
7599 | * Initialize the perf_event context in task_struct | |
7600 | */ | |
7601 | int perf_event_init_task(struct task_struct *child) | |
7602 | { | |
7603 | int ctxn, ret; | |
7604 | ||
8550d7cb ON |
7605 | memset(child->perf_event_ctxp, 0, sizeof(child->perf_event_ctxp)); |
7606 | mutex_init(&child->perf_event_mutex); | |
7607 | INIT_LIST_HEAD(&child->perf_event_list); | |
7608 | ||
8dc85d54 PZ |
7609 | for_each_task_context_nr(ctxn) { |
7610 | ret = perf_event_init_context(child, ctxn); | |
7611 | if (ret) | |
7612 | return ret; | |
7613 | } | |
7614 | ||
7615 | return 0; | |
7616 | } | |
7617 | ||
220b140b PM |
7618 | static void __init perf_event_init_all_cpus(void) |
7619 | { | |
b28ab83c | 7620 | struct swevent_htable *swhash; |
220b140b | 7621 | int cpu; |
220b140b PM |
7622 | |
7623 | for_each_possible_cpu(cpu) { | |
b28ab83c PZ |
7624 | swhash = &per_cpu(swevent_htable, cpu); |
7625 | mutex_init(&swhash->hlist_mutex); | |
e9d2b064 | 7626 | INIT_LIST_HEAD(&per_cpu(rotation_list, cpu)); |
220b140b PM |
7627 | } |
7628 | } | |
7629 | ||
0db0628d | 7630 | static void perf_event_init_cpu(int cpu) |
0793a61d | 7631 | { |
108b02cf | 7632 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
0793a61d | 7633 | |
b28ab83c | 7634 | mutex_lock(&swhash->hlist_mutex); |
4536e4d1 | 7635 | if (swhash->hlist_refcount > 0) { |
76e1d904 FW |
7636 | struct swevent_hlist *hlist; |
7637 | ||
b28ab83c PZ |
7638 | hlist = kzalloc_node(sizeof(*hlist), GFP_KERNEL, cpu_to_node(cpu)); |
7639 | WARN_ON(!hlist); | |
7640 | rcu_assign_pointer(swhash->swevent_hlist, hlist); | |
76e1d904 | 7641 | } |
b28ab83c | 7642 | mutex_unlock(&swhash->hlist_mutex); |
0793a61d TG |
7643 | } |
7644 | ||
c277443c | 7645 | #if defined CONFIG_HOTPLUG_CPU || defined CONFIG_KEXEC |
e9d2b064 | 7646 | static void perf_pmu_rotate_stop(struct pmu *pmu) |
0793a61d | 7647 | { |
e9d2b064 PZ |
7648 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
7649 | ||
7650 | WARN_ON(!irqs_disabled()); | |
7651 | ||
7652 | list_del_init(&cpuctx->rotation_list); | |
7653 | } | |
7654 | ||
108b02cf | 7655 | static void __perf_event_exit_context(void *__info) |
0793a61d | 7656 | { |
108b02cf | 7657 | struct perf_event_context *ctx = __info; |
cdd6c482 | 7658 | struct perf_event *event, *tmp; |
0793a61d | 7659 | |
108b02cf | 7660 | perf_pmu_rotate_stop(ctx->pmu); |
b5ab4cd5 | 7661 | |
889ff015 | 7662 | list_for_each_entry_safe(event, tmp, &ctx->pinned_groups, group_entry) |
fe4b04fa | 7663 | __perf_remove_from_context(event); |
889ff015 | 7664 | list_for_each_entry_safe(event, tmp, &ctx->flexible_groups, group_entry) |
fe4b04fa | 7665 | __perf_remove_from_context(event); |
0793a61d | 7666 | } |
108b02cf PZ |
7667 | |
7668 | static void perf_event_exit_cpu_context(int cpu) | |
7669 | { | |
7670 | struct perf_event_context *ctx; | |
7671 | struct pmu *pmu; | |
7672 | int idx; | |
7673 | ||
7674 | idx = srcu_read_lock(&pmus_srcu); | |
7675 | list_for_each_entry_rcu(pmu, &pmus, entry) { | |
917bdd1c | 7676 | ctx = &per_cpu_ptr(pmu->pmu_cpu_context, cpu)->ctx; |
108b02cf PZ |
7677 | |
7678 | mutex_lock(&ctx->mutex); | |
7679 | smp_call_function_single(cpu, __perf_event_exit_context, ctx, 1); | |
7680 | mutex_unlock(&ctx->mutex); | |
7681 | } | |
7682 | srcu_read_unlock(&pmus_srcu, idx); | |
108b02cf PZ |
7683 | } |
7684 | ||
cdd6c482 | 7685 | static void perf_event_exit_cpu(int cpu) |
0793a61d | 7686 | { |
b28ab83c | 7687 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
d859e29f | 7688 | |
b28ab83c PZ |
7689 | mutex_lock(&swhash->hlist_mutex); |
7690 | swevent_hlist_release(swhash); | |
7691 | mutex_unlock(&swhash->hlist_mutex); | |
76e1d904 | 7692 | |
108b02cf | 7693 | perf_event_exit_cpu_context(cpu); |
0793a61d TG |
7694 | } |
7695 | #else | |
cdd6c482 | 7696 | static inline void perf_event_exit_cpu(int cpu) { } |
0793a61d TG |
7697 | #endif |
7698 | ||
c277443c PZ |
7699 | static int |
7700 | perf_reboot(struct notifier_block *notifier, unsigned long val, void *v) | |
7701 | { | |
7702 | int cpu; | |
7703 | ||
7704 | for_each_online_cpu(cpu) | |
7705 | perf_event_exit_cpu(cpu); | |
7706 | ||
7707 | return NOTIFY_OK; | |
7708 | } | |
7709 | ||
7710 | /* | |
7711 | * Run the perf reboot notifier at the very last possible moment so that | |
7712 | * the generic watchdog code runs as long as possible. | |
7713 | */ | |
7714 | static struct notifier_block perf_reboot_notifier = { | |
7715 | .notifier_call = perf_reboot, | |
7716 | .priority = INT_MIN, | |
7717 | }; | |
7718 | ||
0db0628d | 7719 | static int |
0793a61d TG |
7720 | perf_cpu_notify(struct notifier_block *self, unsigned long action, void *hcpu) |
7721 | { | |
7722 | unsigned int cpu = (long)hcpu; | |
7723 | ||
4536e4d1 | 7724 | switch (action & ~CPU_TASKS_FROZEN) { |
0793a61d TG |
7725 | |
7726 | case CPU_UP_PREPARE: | |
5e11637e | 7727 | case CPU_DOWN_FAILED: |
cdd6c482 | 7728 | perf_event_init_cpu(cpu); |
0793a61d TG |
7729 | break; |
7730 | ||
5e11637e | 7731 | case CPU_UP_CANCELED: |
0793a61d | 7732 | case CPU_DOWN_PREPARE: |
cdd6c482 | 7733 | perf_event_exit_cpu(cpu); |
0793a61d | 7734 | break; |
0793a61d TG |
7735 | default: |
7736 | break; | |
7737 | } | |
7738 | ||
7739 | return NOTIFY_OK; | |
7740 | } | |
7741 | ||
cdd6c482 | 7742 | void __init perf_event_init(void) |
0793a61d | 7743 | { |
3c502e7a JW |
7744 | int ret; |
7745 | ||
2e80a82a PZ |
7746 | idr_init(&pmu_idr); |
7747 | ||
220b140b | 7748 | perf_event_init_all_cpus(); |
b0a873eb | 7749 | init_srcu_struct(&pmus_srcu); |
2e80a82a PZ |
7750 | perf_pmu_register(&perf_swevent, "software", PERF_TYPE_SOFTWARE); |
7751 | perf_pmu_register(&perf_cpu_clock, NULL, -1); | |
7752 | perf_pmu_register(&perf_task_clock, NULL, -1); | |
b0a873eb PZ |
7753 | perf_tp_register(); |
7754 | perf_cpu_notifier(perf_cpu_notify); | |
c277443c | 7755 | register_reboot_notifier(&perf_reboot_notifier); |
3c502e7a JW |
7756 | |
7757 | ret = init_hw_breakpoint(); | |
7758 | WARN(ret, "hw_breakpoint initialization failed with: %d", ret); | |
b2029520 GN |
7759 | |
7760 | /* do not patch jump label more than once per second */ | |
7761 | jump_label_rate_limit(&perf_sched_events, HZ); | |
b01c3a00 JO |
7762 | |
7763 | /* | |
7764 | * Build time assertion that we keep the data_head at the intended | |
7765 | * location. IOW, validation we got the __reserved[] size right. | |
7766 | */ | |
7767 | BUILD_BUG_ON((offsetof(struct perf_event_mmap_page, data_head)) | |
7768 | != 1024); | |
0793a61d | 7769 | } |
abe43400 PZ |
7770 | |
7771 | static int __init perf_event_sysfs_init(void) | |
7772 | { | |
7773 | struct pmu *pmu; | |
7774 | int ret; | |
7775 | ||
7776 | mutex_lock(&pmus_lock); | |
7777 | ||
7778 | ret = bus_register(&pmu_bus); | |
7779 | if (ret) | |
7780 | goto unlock; | |
7781 | ||
7782 | list_for_each_entry(pmu, &pmus, entry) { | |
7783 | if (!pmu->name || pmu->type < 0) | |
7784 | continue; | |
7785 | ||
7786 | ret = pmu_dev_alloc(pmu); | |
7787 | WARN(ret, "Failed to register pmu: %s, reason %d\n", pmu->name, ret); | |
7788 | } | |
7789 | pmu_bus_running = 1; | |
7790 | ret = 0; | |
7791 | ||
7792 | unlock: | |
7793 | mutex_unlock(&pmus_lock); | |
7794 | ||
7795 | return ret; | |
7796 | } | |
7797 | device_initcall(perf_event_sysfs_init); | |
e5d1367f SE |
7798 | |
7799 | #ifdef CONFIG_CGROUP_PERF | |
92fb9748 | 7800 | static struct cgroup_subsys_state *perf_cgroup_css_alloc(struct cgroup *cont) |
e5d1367f SE |
7801 | { |
7802 | struct perf_cgroup *jc; | |
e5d1367f | 7803 | |
1b15d055 | 7804 | jc = kzalloc(sizeof(*jc), GFP_KERNEL); |
e5d1367f SE |
7805 | if (!jc) |
7806 | return ERR_PTR(-ENOMEM); | |
7807 | ||
e5d1367f SE |
7808 | jc->info = alloc_percpu(struct perf_cgroup_info); |
7809 | if (!jc->info) { | |
7810 | kfree(jc); | |
7811 | return ERR_PTR(-ENOMEM); | |
7812 | } | |
7813 | ||
e5d1367f SE |
7814 | return &jc->css; |
7815 | } | |
7816 | ||
92fb9748 | 7817 | static void perf_cgroup_css_free(struct cgroup *cont) |
e5d1367f SE |
7818 | { |
7819 | struct perf_cgroup *jc; | |
7820 | jc = container_of(cgroup_subsys_state(cont, perf_subsys_id), | |
7821 | struct perf_cgroup, css); | |
7822 | free_percpu(jc->info); | |
7823 | kfree(jc); | |
7824 | } | |
7825 | ||
7826 | static int __perf_cgroup_move(void *info) | |
7827 | { | |
7828 | struct task_struct *task = info; | |
7829 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT | PERF_CGROUP_SWIN); | |
7830 | return 0; | |
7831 | } | |
7832 | ||
761b3ef5 | 7833 | static void perf_cgroup_attach(struct cgroup *cgrp, struct cgroup_taskset *tset) |
e5d1367f | 7834 | { |
bb9d97b6 TH |
7835 | struct task_struct *task; |
7836 | ||
7837 | cgroup_taskset_for_each(task, cgrp, tset) | |
7838 | task_function_call(task, __perf_cgroup_move, task); | |
e5d1367f SE |
7839 | } |
7840 | ||
761b3ef5 LZ |
7841 | static void perf_cgroup_exit(struct cgroup *cgrp, struct cgroup *old_cgrp, |
7842 | struct task_struct *task) | |
e5d1367f SE |
7843 | { |
7844 | /* | |
7845 | * cgroup_exit() is called in the copy_process() failure path. | |
7846 | * Ignore this case since the task hasn't ran yet, this avoids | |
7847 | * trying to poke a half freed task state from generic code. | |
7848 | */ | |
7849 | if (!(task->flags & PF_EXITING)) | |
7850 | return; | |
7851 | ||
bb9d97b6 | 7852 | task_function_call(task, __perf_cgroup_move, task); |
e5d1367f SE |
7853 | } |
7854 | ||
7855 | struct cgroup_subsys perf_subsys = { | |
e7e7ee2e IM |
7856 | .name = "perf_event", |
7857 | .subsys_id = perf_subsys_id, | |
92fb9748 TH |
7858 | .css_alloc = perf_cgroup_css_alloc, |
7859 | .css_free = perf_cgroup_css_free, | |
e7e7ee2e | 7860 | .exit = perf_cgroup_exit, |
bb9d97b6 | 7861 | .attach = perf_cgroup_attach, |
e5d1367f SE |
7862 | }; |
7863 | #endif /* CONFIG_CGROUP_PERF */ |