Commit | Line | Data |
---|---|---|
0793a61d | 1 | /* |
57c0c15b | 2 | * Performance events core code: |
0793a61d | 3 | * |
98144511 | 4 | * Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de> |
e7e7ee2e | 5 | * Copyright (C) 2008-2011 Red Hat, Inc., Ingo Molnar |
90eec103 | 6 | * Copyright (C) 2008-2011 Red Hat, Inc., Peter Zijlstra |
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> |
39bed6cb | 37 | #include <linux/cgroup.h> |
cdd6c482 | 38 | #include <linux/perf_event.h> |
af658dca | 39 | #include <linux/trace_events.h> |
3c502e7a | 40 | #include <linux/hw_breakpoint.h> |
c5ebcedb | 41 | #include <linux/mm_types.h> |
c464c76e | 42 | #include <linux/module.h> |
f972eb63 | 43 | #include <linux/mman.h> |
b3f20785 | 44 | #include <linux/compat.h> |
2541517c AS |
45 | #include <linux/bpf.h> |
46 | #include <linux/filter.h> | |
0793a61d | 47 | |
76369139 FW |
48 | #include "internal.h" |
49 | ||
4e193bd4 TB |
50 | #include <asm/irq_regs.h> |
51 | ||
fadfe7be JO |
52 | static struct workqueue_struct *perf_wq; |
53 | ||
272325c4 PZ |
54 | typedef int (*remote_function_f)(void *); |
55 | ||
fe4b04fa | 56 | struct remote_function_call { |
e7e7ee2e | 57 | struct task_struct *p; |
272325c4 | 58 | remote_function_f func; |
e7e7ee2e IM |
59 | void *info; |
60 | int ret; | |
fe4b04fa PZ |
61 | }; |
62 | ||
63 | static void remote_function(void *data) | |
64 | { | |
65 | struct remote_function_call *tfc = data; | |
66 | struct task_struct *p = tfc->p; | |
67 | ||
68 | if (p) { | |
69 | tfc->ret = -EAGAIN; | |
70 | if (task_cpu(p) != smp_processor_id() || !task_curr(p)) | |
71 | return; | |
72 | } | |
73 | ||
74 | tfc->ret = tfc->func(tfc->info); | |
75 | } | |
76 | ||
77 | /** | |
78 | * task_function_call - call a function on the cpu on which a task runs | |
79 | * @p: the task to evaluate | |
80 | * @func: the function to be called | |
81 | * @info: the function call argument | |
82 | * | |
83 | * Calls the function @func when the task is currently running. This might | |
84 | * be on the current CPU, which just calls the function directly | |
85 | * | |
86 | * returns: @func return value, or | |
87 | * -ESRCH - when the process isn't running | |
88 | * -EAGAIN - when the process moved away | |
89 | */ | |
90 | static int | |
272325c4 | 91 | task_function_call(struct task_struct *p, remote_function_f func, void *info) |
fe4b04fa PZ |
92 | { |
93 | struct remote_function_call data = { | |
e7e7ee2e IM |
94 | .p = p, |
95 | .func = func, | |
96 | .info = info, | |
97 | .ret = -ESRCH, /* No such (running) process */ | |
fe4b04fa PZ |
98 | }; |
99 | ||
100 | if (task_curr(p)) | |
101 | smp_call_function_single(task_cpu(p), remote_function, &data, 1); | |
102 | ||
103 | return data.ret; | |
104 | } | |
105 | ||
106 | /** | |
107 | * cpu_function_call - call a function on the cpu | |
108 | * @func: the function to be called | |
109 | * @info: the function call argument | |
110 | * | |
111 | * Calls the function @func on the remote cpu. | |
112 | * | |
113 | * returns: @func return value or -ENXIO when the cpu is offline | |
114 | */ | |
272325c4 | 115 | static int cpu_function_call(int cpu, remote_function_f func, void *info) |
fe4b04fa PZ |
116 | { |
117 | struct remote_function_call data = { | |
e7e7ee2e IM |
118 | .p = NULL, |
119 | .func = func, | |
120 | .info = info, | |
121 | .ret = -ENXIO, /* No such CPU */ | |
fe4b04fa PZ |
122 | }; |
123 | ||
124 | smp_call_function_single(cpu, remote_function, &data, 1); | |
125 | ||
126 | return data.ret; | |
127 | } | |
128 | ||
0017960f PZ |
129 | static void event_function_call(struct perf_event *event, |
130 | int (*active)(void *), | |
131 | void (*inactive)(void *), | |
132 | void *data) | |
133 | { | |
134 | struct perf_event_context *ctx = event->ctx; | |
135 | struct task_struct *task = ctx->task; | |
136 | ||
137 | if (!task) { | |
138 | cpu_function_call(event->cpu, active, data); | |
139 | return; | |
140 | } | |
141 | ||
142 | again: | |
143 | if (!task_function_call(task, active, data)) | |
144 | return; | |
145 | ||
146 | raw_spin_lock_irq(&ctx->lock); | |
147 | if (ctx->is_active) { | |
148 | /* | |
149 | * Reload the task pointer, it might have been changed by | |
150 | * a concurrent perf_event_context_sched_out(). | |
151 | */ | |
152 | task = ctx->task; | |
153 | raw_spin_unlock_irq(&ctx->lock); | |
154 | goto again; | |
155 | } | |
156 | inactive(data); | |
157 | raw_spin_unlock_irq(&ctx->lock); | |
158 | } | |
159 | ||
f8697762 JO |
160 | #define EVENT_OWNER_KERNEL ((void *) -1) |
161 | ||
162 | static bool is_kernel_event(struct perf_event *event) | |
163 | { | |
164 | return event->owner == EVENT_OWNER_KERNEL; | |
165 | } | |
166 | ||
e5d1367f SE |
167 | #define PERF_FLAG_ALL (PERF_FLAG_FD_NO_GROUP |\ |
168 | PERF_FLAG_FD_OUTPUT |\ | |
a21b0b35 YD |
169 | PERF_FLAG_PID_CGROUP |\ |
170 | PERF_FLAG_FD_CLOEXEC) | |
e5d1367f | 171 | |
bce38cd5 SE |
172 | /* |
173 | * branch priv levels that need permission checks | |
174 | */ | |
175 | #define PERF_SAMPLE_BRANCH_PERM_PLM \ | |
176 | (PERF_SAMPLE_BRANCH_KERNEL |\ | |
177 | PERF_SAMPLE_BRANCH_HV) | |
178 | ||
0b3fcf17 SE |
179 | enum event_type_t { |
180 | EVENT_FLEXIBLE = 0x1, | |
181 | EVENT_PINNED = 0x2, | |
182 | EVENT_ALL = EVENT_FLEXIBLE | EVENT_PINNED, | |
183 | }; | |
184 | ||
e5d1367f SE |
185 | /* |
186 | * perf_sched_events : >0 events exist | |
187 | * perf_cgroup_events: >0 per-cpu cgroup events exist on this cpu | |
188 | */ | |
c5905afb | 189 | struct static_key_deferred perf_sched_events __read_mostly; |
e5d1367f | 190 | static DEFINE_PER_CPU(atomic_t, perf_cgroup_events); |
ba532500 | 191 | static DEFINE_PER_CPU(int, perf_sched_cb_usages); |
e5d1367f | 192 | |
cdd6c482 IM |
193 | static atomic_t nr_mmap_events __read_mostly; |
194 | static atomic_t nr_comm_events __read_mostly; | |
195 | static atomic_t nr_task_events __read_mostly; | |
948b26b6 | 196 | static atomic_t nr_freq_events __read_mostly; |
45ac1403 | 197 | static atomic_t nr_switch_events __read_mostly; |
9ee318a7 | 198 | |
108b02cf PZ |
199 | static LIST_HEAD(pmus); |
200 | static DEFINE_MUTEX(pmus_lock); | |
201 | static struct srcu_struct pmus_srcu; | |
202 | ||
0764771d | 203 | /* |
cdd6c482 | 204 | * perf event paranoia level: |
0fbdea19 IM |
205 | * -1 - not paranoid at all |
206 | * 0 - disallow raw tracepoint access for unpriv | |
cdd6c482 | 207 | * 1 - disallow cpu events for unpriv |
0fbdea19 | 208 | * 2 - disallow kernel profiling for unpriv |
0764771d | 209 | */ |
cdd6c482 | 210 | int sysctl_perf_event_paranoid __read_mostly = 1; |
0764771d | 211 | |
20443384 FW |
212 | /* Minimum for 512 kiB + 1 user control page */ |
213 | int sysctl_perf_event_mlock __read_mostly = 512 + (PAGE_SIZE / 1024); /* 'free' kiB per user */ | |
df58ab24 PZ |
214 | |
215 | /* | |
cdd6c482 | 216 | * max perf event sample rate |
df58ab24 | 217 | */ |
14c63f17 DH |
218 | #define DEFAULT_MAX_SAMPLE_RATE 100000 |
219 | #define DEFAULT_SAMPLE_PERIOD_NS (NSEC_PER_SEC / DEFAULT_MAX_SAMPLE_RATE) | |
220 | #define DEFAULT_CPU_TIME_MAX_PERCENT 25 | |
221 | ||
222 | int sysctl_perf_event_sample_rate __read_mostly = DEFAULT_MAX_SAMPLE_RATE; | |
223 | ||
224 | static int max_samples_per_tick __read_mostly = DIV_ROUND_UP(DEFAULT_MAX_SAMPLE_RATE, HZ); | |
225 | static int perf_sample_period_ns __read_mostly = DEFAULT_SAMPLE_PERIOD_NS; | |
226 | ||
d9494cb4 PZ |
227 | static int perf_sample_allowed_ns __read_mostly = |
228 | DEFAULT_SAMPLE_PERIOD_NS * DEFAULT_CPU_TIME_MAX_PERCENT / 100; | |
14c63f17 | 229 | |
18ab2cd3 | 230 | static void update_perf_cpu_limits(void) |
14c63f17 DH |
231 | { |
232 | u64 tmp = perf_sample_period_ns; | |
233 | ||
234 | tmp *= sysctl_perf_cpu_time_max_percent; | |
e5302920 | 235 | do_div(tmp, 100); |
d9494cb4 | 236 | ACCESS_ONCE(perf_sample_allowed_ns) = tmp; |
14c63f17 | 237 | } |
163ec435 | 238 | |
9e630205 SE |
239 | static int perf_rotate_context(struct perf_cpu_context *cpuctx); |
240 | ||
163ec435 PZ |
241 | int perf_proc_update_handler(struct ctl_table *table, int write, |
242 | void __user *buffer, size_t *lenp, | |
243 | loff_t *ppos) | |
244 | { | |
723478c8 | 245 | int ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
163ec435 PZ |
246 | |
247 | if (ret || !write) | |
248 | return ret; | |
249 | ||
250 | max_samples_per_tick = DIV_ROUND_UP(sysctl_perf_event_sample_rate, HZ); | |
14c63f17 DH |
251 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; |
252 | update_perf_cpu_limits(); | |
253 | ||
254 | return 0; | |
255 | } | |
256 | ||
257 | int sysctl_perf_cpu_time_max_percent __read_mostly = DEFAULT_CPU_TIME_MAX_PERCENT; | |
258 | ||
259 | int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write, | |
260 | void __user *buffer, size_t *lenp, | |
261 | loff_t *ppos) | |
262 | { | |
263 | int ret = proc_dointvec(table, write, buffer, lenp, ppos); | |
264 | ||
265 | if (ret || !write) | |
266 | return ret; | |
267 | ||
268 | update_perf_cpu_limits(); | |
163ec435 PZ |
269 | |
270 | return 0; | |
271 | } | |
1ccd1549 | 272 | |
14c63f17 DH |
273 | /* |
274 | * perf samples are done in some very critical code paths (NMIs). | |
275 | * If they take too much CPU time, the system can lock up and not | |
276 | * get any real work done. This will drop the sample rate when | |
277 | * we detect that events are taking too long. | |
278 | */ | |
279 | #define NR_ACCUMULATED_SAMPLES 128 | |
d9494cb4 | 280 | static DEFINE_PER_CPU(u64, running_sample_length); |
14c63f17 | 281 | |
6a02ad66 | 282 | static void perf_duration_warn(struct irq_work *w) |
14c63f17 | 283 | { |
6a02ad66 | 284 | u64 allowed_ns = ACCESS_ONCE(perf_sample_allowed_ns); |
14c63f17 | 285 | u64 avg_local_sample_len; |
e5302920 | 286 | u64 local_samples_len; |
6a02ad66 | 287 | |
4a32fea9 | 288 | local_samples_len = __this_cpu_read(running_sample_length); |
6a02ad66 PZ |
289 | avg_local_sample_len = local_samples_len/NR_ACCUMULATED_SAMPLES; |
290 | ||
291 | printk_ratelimited(KERN_WARNING | |
292 | "perf interrupt took too long (%lld > %lld), lowering " | |
293 | "kernel.perf_event_max_sample_rate to %d\n", | |
cd578abb | 294 | avg_local_sample_len, allowed_ns >> 1, |
6a02ad66 PZ |
295 | sysctl_perf_event_sample_rate); |
296 | } | |
297 | ||
298 | static DEFINE_IRQ_WORK(perf_duration_work, perf_duration_warn); | |
299 | ||
300 | void perf_sample_event_took(u64 sample_len_ns) | |
301 | { | |
d9494cb4 | 302 | u64 allowed_ns = ACCESS_ONCE(perf_sample_allowed_ns); |
6a02ad66 PZ |
303 | u64 avg_local_sample_len; |
304 | u64 local_samples_len; | |
14c63f17 | 305 | |
d9494cb4 | 306 | if (allowed_ns == 0) |
14c63f17 DH |
307 | return; |
308 | ||
309 | /* decay the counter by 1 average sample */ | |
4a32fea9 | 310 | local_samples_len = __this_cpu_read(running_sample_length); |
14c63f17 DH |
311 | local_samples_len -= local_samples_len/NR_ACCUMULATED_SAMPLES; |
312 | local_samples_len += sample_len_ns; | |
4a32fea9 | 313 | __this_cpu_write(running_sample_length, local_samples_len); |
14c63f17 DH |
314 | |
315 | /* | |
316 | * note: this will be biased artifically low until we have | |
317 | * seen NR_ACCUMULATED_SAMPLES. Doing it this way keeps us | |
318 | * from having to maintain a count. | |
319 | */ | |
320 | avg_local_sample_len = local_samples_len/NR_ACCUMULATED_SAMPLES; | |
321 | ||
d9494cb4 | 322 | if (avg_local_sample_len <= allowed_ns) |
14c63f17 DH |
323 | return; |
324 | ||
325 | if (max_samples_per_tick <= 1) | |
326 | return; | |
327 | ||
328 | max_samples_per_tick = DIV_ROUND_UP(max_samples_per_tick, 2); | |
329 | sysctl_perf_event_sample_rate = max_samples_per_tick * HZ; | |
330 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; | |
331 | ||
14c63f17 | 332 | update_perf_cpu_limits(); |
6a02ad66 | 333 | |
cd578abb PZ |
334 | if (!irq_work_queue(&perf_duration_work)) { |
335 | early_printk("perf interrupt took too long (%lld > %lld), lowering " | |
336 | "kernel.perf_event_max_sample_rate to %d\n", | |
337 | avg_local_sample_len, allowed_ns >> 1, | |
338 | sysctl_perf_event_sample_rate); | |
339 | } | |
14c63f17 DH |
340 | } |
341 | ||
cdd6c482 | 342 | static atomic64_t perf_event_id; |
a96bbc16 | 343 | |
0b3fcf17 SE |
344 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, |
345 | enum event_type_t event_type); | |
346 | ||
347 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
348 | enum event_type_t event_type, |
349 | struct task_struct *task); | |
350 | ||
351 | static void update_context_time(struct perf_event_context *ctx); | |
352 | static u64 perf_event_time(struct perf_event *event); | |
0b3fcf17 | 353 | |
cdd6c482 | 354 | void __weak perf_event_print_debug(void) { } |
0793a61d | 355 | |
84c79910 | 356 | extern __weak const char *perf_pmu_name(void) |
0793a61d | 357 | { |
84c79910 | 358 | return "pmu"; |
0793a61d TG |
359 | } |
360 | ||
0b3fcf17 SE |
361 | static inline u64 perf_clock(void) |
362 | { | |
363 | return local_clock(); | |
364 | } | |
365 | ||
34f43927 PZ |
366 | static inline u64 perf_event_clock(struct perf_event *event) |
367 | { | |
368 | return event->clock(); | |
369 | } | |
370 | ||
e5d1367f SE |
371 | static inline struct perf_cpu_context * |
372 | __get_cpu_context(struct perf_event_context *ctx) | |
373 | { | |
374 | return this_cpu_ptr(ctx->pmu->pmu_cpu_context); | |
375 | } | |
376 | ||
facc4307 PZ |
377 | static void perf_ctx_lock(struct perf_cpu_context *cpuctx, |
378 | struct perf_event_context *ctx) | |
379 | { | |
380 | raw_spin_lock(&cpuctx->ctx.lock); | |
381 | if (ctx) | |
382 | raw_spin_lock(&ctx->lock); | |
383 | } | |
384 | ||
385 | static void perf_ctx_unlock(struct perf_cpu_context *cpuctx, | |
386 | struct perf_event_context *ctx) | |
387 | { | |
388 | if (ctx) | |
389 | raw_spin_unlock(&ctx->lock); | |
390 | raw_spin_unlock(&cpuctx->ctx.lock); | |
391 | } | |
392 | ||
e5d1367f SE |
393 | #ifdef CONFIG_CGROUP_PERF |
394 | ||
e5d1367f SE |
395 | static inline bool |
396 | perf_cgroup_match(struct perf_event *event) | |
397 | { | |
398 | struct perf_event_context *ctx = event->ctx; | |
399 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
400 | ||
ef824fa1 TH |
401 | /* @event doesn't care about cgroup */ |
402 | if (!event->cgrp) | |
403 | return true; | |
404 | ||
405 | /* wants specific cgroup scope but @cpuctx isn't associated with any */ | |
406 | if (!cpuctx->cgrp) | |
407 | return false; | |
408 | ||
409 | /* | |
410 | * Cgroup scoping is recursive. An event enabled for a cgroup is | |
411 | * also enabled for all its descendant cgroups. If @cpuctx's | |
412 | * cgroup is a descendant of @event's (the test covers identity | |
413 | * case), it's a match. | |
414 | */ | |
415 | return cgroup_is_descendant(cpuctx->cgrp->css.cgroup, | |
416 | event->cgrp->css.cgroup); | |
e5d1367f SE |
417 | } |
418 | ||
e5d1367f SE |
419 | static inline void perf_detach_cgroup(struct perf_event *event) |
420 | { | |
4e2ba650 | 421 | css_put(&event->cgrp->css); |
e5d1367f SE |
422 | event->cgrp = NULL; |
423 | } | |
424 | ||
425 | static inline int is_cgroup_event(struct perf_event *event) | |
426 | { | |
427 | return event->cgrp != NULL; | |
428 | } | |
429 | ||
430 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
431 | { | |
432 | struct perf_cgroup_info *t; | |
433 | ||
434 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
435 | return t->time; | |
436 | } | |
437 | ||
438 | static inline void __update_cgrp_time(struct perf_cgroup *cgrp) | |
439 | { | |
440 | struct perf_cgroup_info *info; | |
441 | u64 now; | |
442 | ||
443 | now = perf_clock(); | |
444 | ||
445 | info = this_cpu_ptr(cgrp->info); | |
446 | ||
447 | info->time += now - info->timestamp; | |
448 | info->timestamp = now; | |
449 | } | |
450 | ||
451 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
452 | { | |
453 | struct perf_cgroup *cgrp_out = cpuctx->cgrp; | |
454 | if (cgrp_out) | |
455 | __update_cgrp_time(cgrp_out); | |
456 | } | |
457 | ||
458 | static inline void update_cgrp_time_from_event(struct perf_event *event) | |
459 | { | |
3f7cce3c SE |
460 | struct perf_cgroup *cgrp; |
461 | ||
e5d1367f | 462 | /* |
3f7cce3c SE |
463 | * ensure we access cgroup data only when needed and |
464 | * when we know the cgroup is pinned (css_get) | |
e5d1367f | 465 | */ |
3f7cce3c | 466 | if (!is_cgroup_event(event)) |
e5d1367f SE |
467 | return; |
468 | ||
614e4c4e | 469 | cgrp = perf_cgroup_from_task(current, event->ctx); |
3f7cce3c SE |
470 | /* |
471 | * Do not update time when cgroup is not active | |
472 | */ | |
473 | if (cgrp == event->cgrp) | |
474 | __update_cgrp_time(event->cgrp); | |
e5d1367f SE |
475 | } |
476 | ||
477 | static inline void | |
3f7cce3c SE |
478 | perf_cgroup_set_timestamp(struct task_struct *task, |
479 | struct perf_event_context *ctx) | |
e5d1367f SE |
480 | { |
481 | struct perf_cgroup *cgrp; | |
482 | struct perf_cgroup_info *info; | |
483 | ||
3f7cce3c SE |
484 | /* |
485 | * ctx->lock held by caller | |
486 | * ensure we do not access cgroup data | |
487 | * unless we have the cgroup pinned (css_get) | |
488 | */ | |
489 | if (!task || !ctx->nr_cgroups) | |
e5d1367f SE |
490 | return; |
491 | ||
614e4c4e | 492 | cgrp = perf_cgroup_from_task(task, ctx); |
e5d1367f | 493 | info = this_cpu_ptr(cgrp->info); |
3f7cce3c | 494 | info->timestamp = ctx->timestamp; |
e5d1367f SE |
495 | } |
496 | ||
497 | #define PERF_CGROUP_SWOUT 0x1 /* cgroup switch out every event */ | |
498 | #define PERF_CGROUP_SWIN 0x2 /* cgroup switch in events based on task */ | |
499 | ||
500 | /* | |
501 | * reschedule events based on the cgroup constraint of task. | |
502 | * | |
503 | * mode SWOUT : schedule out everything | |
504 | * mode SWIN : schedule in based on cgroup for next | |
505 | */ | |
18ab2cd3 | 506 | static void perf_cgroup_switch(struct task_struct *task, int mode) |
e5d1367f SE |
507 | { |
508 | struct perf_cpu_context *cpuctx; | |
509 | struct pmu *pmu; | |
510 | unsigned long flags; | |
511 | ||
512 | /* | |
513 | * disable interrupts to avoid geting nr_cgroup | |
514 | * changes via __perf_event_disable(). Also | |
515 | * avoids preemption. | |
516 | */ | |
517 | local_irq_save(flags); | |
518 | ||
519 | /* | |
520 | * we reschedule only in the presence of cgroup | |
521 | * constrained events. | |
522 | */ | |
e5d1367f SE |
523 | |
524 | list_for_each_entry_rcu(pmu, &pmus, entry) { | |
e5d1367f | 525 | cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
95cf59ea PZ |
526 | if (cpuctx->unique_pmu != pmu) |
527 | continue; /* ensure we process each cpuctx once */ | |
e5d1367f | 528 | |
e5d1367f SE |
529 | /* |
530 | * perf_cgroup_events says at least one | |
531 | * context on this CPU has cgroup events. | |
532 | * | |
533 | * ctx->nr_cgroups reports the number of cgroup | |
534 | * events for a context. | |
535 | */ | |
536 | if (cpuctx->ctx.nr_cgroups > 0) { | |
facc4307 PZ |
537 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
538 | perf_pmu_disable(cpuctx->ctx.pmu); | |
e5d1367f SE |
539 | |
540 | if (mode & PERF_CGROUP_SWOUT) { | |
541 | cpu_ctx_sched_out(cpuctx, EVENT_ALL); | |
542 | /* | |
543 | * must not be done before ctxswout due | |
544 | * to event_filter_match() in event_sched_out() | |
545 | */ | |
546 | cpuctx->cgrp = NULL; | |
547 | } | |
548 | ||
549 | if (mode & PERF_CGROUP_SWIN) { | |
e566b76e | 550 | WARN_ON_ONCE(cpuctx->cgrp); |
95cf59ea PZ |
551 | /* |
552 | * set cgrp before ctxsw in to allow | |
553 | * event_filter_match() to not have to pass | |
554 | * task around | |
614e4c4e SE |
555 | * we pass the cpuctx->ctx to perf_cgroup_from_task() |
556 | * because cgorup events are only per-cpu | |
e5d1367f | 557 | */ |
614e4c4e | 558 | cpuctx->cgrp = perf_cgroup_from_task(task, &cpuctx->ctx); |
e5d1367f SE |
559 | cpu_ctx_sched_in(cpuctx, EVENT_ALL, task); |
560 | } | |
facc4307 PZ |
561 | perf_pmu_enable(cpuctx->ctx.pmu); |
562 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
e5d1367f | 563 | } |
e5d1367f SE |
564 | } |
565 | ||
e5d1367f SE |
566 | local_irq_restore(flags); |
567 | } | |
568 | ||
a8d757ef SE |
569 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
570 | struct task_struct *next) | |
e5d1367f | 571 | { |
a8d757ef SE |
572 | struct perf_cgroup *cgrp1; |
573 | struct perf_cgroup *cgrp2 = NULL; | |
574 | ||
ddaaf4e2 | 575 | rcu_read_lock(); |
a8d757ef SE |
576 | /* |
577 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
578 | * we do not need to pass the ctx here because we know |
579 | * we are holding the rcu lock | |
a8d757ef | 580 | */ |
614e4c4e | 581 | cgrp1 = perf_cgroup_from_task(task, NULL); |
70a01657 | 582 | cgrp2 = perf_cgroup_from_task(next, NULL); |
a8d757ef SE |
583 | |
584 | /* | |
585 | * only schedule out current cgroup events if we know | |
586 | * that we are switching to a different cgroup. Otherwise, | |
587 | * do no touch the cgroup events. | |
588 | */ | |
589 | if (cgrp1 != cgrp2) | |
590 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT); | |
ddaaf4e2 SE |
591 | |
592 | rcu_read_unlock(); | |
e5d1367f SE |
593 | } |
594 | ||
a8d757ef SE |
595 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
596 | struct task_struct *task) | |
e5d1367f | 597 | { |
a8d757ef SE |
598 | struct perf_cgroup *cgrp1; |
599 | struct perf_cgroup *cgrp2 = NULL; | |
600 | ||
ddaaf4e2 | 601 | rcu_read_lock(); |
a8d757ef SE |
602 | /* |
603 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
604 | * we do not need to pass the ctx here because we know |
605 | * we are holding the rcu lock | |
a8d757ef | 606 | */ |
614e4c4e | 607 | cgrp1 = perf_cgroup_from_task(task, NULL); |
614e4c4e | 608 | cgrp2 = perf_cgroup_from_task(prev, NULL); |
a8d757ef SE |
609 | |
610 | /* | |
611 | * only need to schedule in cgroup events if we are changing | |
612 | * cgroup during ctxsw. Cgroup events were not scheduled | |
613 | * out of ctxsw out if that was not the case. | |
614 | */ | |
615 | if (cgrp1 != cgrp2) | |
616 | perf_cgroup_switch(task, PERF_CGROUP_SWIN); | |
ddaaf4e2 SE |
617 | |
618 | rcu_read_unlock(); | |
e5d1367f SE |
619 | } |
620 | ||
621 | static inline int perf_cgroup_connect(int fd, struct perf_event *event, | |
622 | struct perf_event_attr *attr, | |
623 | struct perf_event *group_leader) | |
624 | { | |
625 | struct perf_cgroup *cgrp; | |
626 | struct cgroup_subsys_state *css; | |
2903ff01 AV |
627 | struct fd f = fdget(fd); |
628 | int ret = 0; | |
e5d1367f | 629 | |
2903ff01 | 630 | if (!f.file) |
e5d1367f SE |
631 | return -EBADF; |
632 | ||
b583043e | 633 | css = css_tryget_online_from_dir(f.file->f_path.dentry, |
ec903c0c | 634 | &perf_event_cgrp_subsys); |
3db272c0 LZ |
635 | if (IS_ERR(css)) { |
636 | ret = PTR_ERR(css); | |
637 | goto out; | |
638 | } | |
e5d1367f SE |
639 | |
640 | cgrp = container_of(css, struct perf_cgroup, css); | |
641 | event->cgrp = cgrp; | |
642 | ||
643 | /* | |
644 | * all events in a group must monitor | |
645 | * the same cgroup because a task belongs | |
646 | * to only one perf cgroup at a time | |
647 | */ | |
648 | if (group_leader && group_leader->cgrp != cgrp) { | |
649 | perf_detach_cgroup(event); | |
650 | ret = -EINVAL; | |
e5d1367f | 651 | } |
3db272c0 | 652 | out: |
2903ff01 | 653 | fdput(f); |
e5d1367f SE |
654 | return ret; |
655 | } | |
656 | ||
657 | static inline void | |
658 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
659 | { | |
660 | struct perf_cgroup_info *t; | |
661 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
662 | event->shadow_ctx_time = now - t->timestamp; | |
663 | } | |
664 | ||
665 | static inline void | |
666 | perf_cgroup_defer_enabled(struct perf_event *event) | |
667 | { | |
668 | /* | |
669 | * when the current task's perf cgroup does not match | |
670 | * the event's, we need to remember to call the | |
671 | * perf_mark_enable() function the first time a task with | |
672 | * a matching perf cgroup is scheduled in. | |
673 | */ | |
674 | if (is_cgroup_event(event) && !perf_cgroup_match(event)) | |
675 | event->cgrp_defer_enabled = 1; | |
676 | } | |
677 | ||
678 | static inline void | |
679 | perf_cgroup_mark_enabled(struct perf_event *event, | |
680 | struct perf_event_context *ctx) | |
681 | { | |
682 | struct perf_event *sub; | |
683 | u64 tstamp = perf_event_time(event); | |
684 | ||
685 | if (!event->cgrp_defer_enabled) | |
686 | return; | |
687 | ||
688 | event->cgrp_defer_enabled = 0; | |
689 | ||
690 | event->tstamp_enabled = tstamp - event->total_time_enabled; | |
691 | list_for_each_entry(sub, &event->sibling_list, group_entry) { | |
692 | if (sub->state >= PERF_EVENT_STATE_INACTIVE) { | |
693 | sub->tstamp_enabled = tstamp - sub->total_time_enabled; | |
694 | sub->cgrp_defer_enabled = 0; | |
695 | } | |
696 | } | |
697 | } | |
698 | #else /* !CONFIG_CGROUP_PERF */ | |
699 | ||
700 | static inline bool | |
701 | perf_cgroup_match(struct perf_event *event) | |
702 | { | |
703 | return true; | |
704 | } | |
705 | ||
706 | static inline void perf_detach_cgroup(struct perf_event *event) | |
707 | {} | |
708 | ||
709 | static inline int is_cgroup_event(struct perf_event *event) | |
710 | { | |
711 | return 0; | |
712 | } | |
713 | ||
714 | static inline u64 perf_cgroup_event_cgrp_time(struct perf_event *event) | |
715 | { | |
716 | return 0; | |
717 | } | |
718 | ||
719 | static inline void update_cgrp_time_from_event(struct perf_event *event) | |
720 | { | |
721 | } | |
722 | ||
723 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
724 | { | |
725 | } | |
726 | ||
a8d757ef SE |
727 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
728 | struct task_struct *next) | |
e5d1367f SE |
729 | { |
730 | } | |
731 | ||
a8d757ef SE |
732 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
733 | struct task_struct *task) | |
e5d1367f SE |
734 | { |
735 | } | |
736 | ||
737 | static inline int perf_cgroup_connect(pid_t pid, struct perf_event *event, | |
738 | struct perf_event_attr *attr, | |
739 | struct perf_event *group_leader) | |
740 | { | |
741 | return -EINVAL; | |
742 | } | |
743 | ||
744 | static inline void | |
3f7cce3c SE |
745 | perf_cgroup_set_timestamp(struct task_struct *task, |
746 | struct perf_event_context *ctx) | |
e5d1367f SE |
747 | { |
748 | } | |
749 | ||
750 | void | |
751 | perf_cgroup_switch(struct task_struct *task, struct task_struct *next) | |
752 | { | |
753 | } | |
754 | ||
755 | static inline void | |
756 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
757 | { | |
758 | } | |
759 | ||
760 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
761 | { | |
762 | return 0; | |
763 | } | |
764 | ||
765 | static inline void | |
766 | perf_cgroup_defer_enabled(struct perf_event *event) | |
767 | { | |
768 | } | |
769 | ||
770 | static inline void | |
771 | perf_cgroup_mark_enabled(struct perf_event *event, | |
772 | struct perf_event_context *ctx) | |
773 | { | |
774 | } | |
775 | #endif | |
776 | ||
9e630205 SE |
777 | /* |
778 | * set default to be dependent on timer tick just | |
779 | * like original code | |
780 | */ | |
781 | #define PERF_CPU_HRTIMER (1000 / HZ) | |
782 | /* | |
783 | * function must be called with interrupts disbled | |
784 | */ | |
272325c4 | 785 | static enum hrtimer_restart perf_mux_hrtimer_handler(struct hrtimer *hr) |
9e630205 SE |
786 | { |
787 | struct perf_cpu_context *cpuctx; | |
9e630205 SE |
788 | int rotations = 0; |
789 | ||
790 | WARN_ON(!irqs_disabled()); | |
791 | ||
792 | cpuctx = container_of(hr, struct perf_cpu_context, hrtimer); | |
9e630205 SE |
793 | rotations = perf_rotate_context(cpuctx); |
794 | ||
4cfafd30 PZ |
795 | raw_spin_lock(&cpuctx->hrtimer_lock); |
796 | if (rotations) | |
9e630205 | 797 | hrtimer_forward_now(hr, cpuctx->hrtimer_interval); |
4cfafd30 PZ |
798 | else |
799 | cpuctx->hrtimer_active = 0; | |
800 | raw_spin_unlock(&cpuctx->hrtimer_lock); | |
9e630205 | 801 | |
4cfafd30 | 802 | return rotations ? HRTIMER_RESTART : HRTIMER_NORESTART; |
9e630205 SE |
803 | } |
804 | ||
272325c4 | 805 | static void __perf_mux_hrtimer_init(struct perf_cpu_context *cpuctx, int cpu) |
9e630205 | 806 | { |
272325c4 | 807 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 808 | struct pmu *pmu = cpuctx->ctx.pmu; |
272325c4 | 809 | u64 interval; |
9e630205 SE |
810 | |
811 | /* no multiplexing needed for SW PMU */ | |
812 | if (pmu->task_ctx_nr == perf_sw_context) | |
813 | return; | |
814 | ||
62b85639 SE |
815 | /* |
816 | * check default is sane, if not set then force to | |
817 | * default interval (1/tick) | |
818 | */ | |
272325c4 PZ |
819 | interval = pmu->hrtimer_interval_ms; |
820 | if (interval < 1) | |
821 | interval = pmu->hrtimer_interval_ms = PERF_CPU_HRTIMER; | |
62b85639 | 822 | |
272325c4 | 823 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * interval); |
9e630205 | 824 | |
4cfafd30 PZ |
825 | raw_spin_lock_init(&cpuctx->hrtimer_lock); |
826 | hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_PINNED); | |
272325c4 | 827 | timer->function = perf_mux_hrtimer_handler; |
9e630205 SE |
828 | } |
829 | ||
272325c4 | 830 | static int perf_mux_hrtimer_restart(struct perf_cpu_context *cpuctx) |
9e630205 | 831 | { |
272325c4 | 832 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 833 | struct pmu *pmu = cpuctx->ctx.pmu; |
4cfafd30 | 834 | unsigned long flags; |
9e630205 SE |
835 | |
836 | /* not for SW PMU */ | |
837 | if (pmu->task_ctx_nr == perf_sw_context) | |
272325c4 | 838 | return 0; |
9e630205 | 839 | |
4cfafd30 PZ |
840 | raw_spin_lock_irqsave(&cpuctx->hrtimer_lock, flags); |
841 | if (!cpuctx->hrtimer_active) { | |
842 | cpuctx->hrtimer_active = 1; | |
843 | hrtimer_forward_now(timer, cpuctx->hrtimer_interval); | |
844 | hrtimer_start_expires(timer, HRTIMER_MODE_ABS_PINNED); | |
845 | } | |
846 | raw_spin_unlock_irqrestore(&cpuctx->hrtimer_lock, flags); | |
9e630205 | 847 | |
272325c4 | 848 | return 0; |
9e630205 SE |
849 | } |
850 | ||
33696fc0 | 851 | void perf_pmu_disable(struct pmu *pmu) |
9e35ad38 | 852 | { |
33696fc0 PZ |
853 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
854 | if (!(*count)++) | |
855 | pmu->pmu_disable(pmu); | |
9e35ad38 | 856 | } |
9e35ad38 | 857 | |
33696fc0 | 858 | void perf_pmu_enable(struct pmu *pmu) |
9e35ad38 | 859 | { |
33696fc0 PZ |
860 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
861 | if (!--(*count)) | |
862 | pmu->pmu_enable(pmu); | |
9e35ad38 | 863 | } |
9e35ad38 | 864 | |
2fde4f94 | 865 | static DEFINE_PER_CPU(struct list_head, active_ctx_list); |
e9d2b064 PZ |
866 | |
867 | /* | |
2fde4f94 MR |
868 | * perf_event_ctx_activate(), perf_event_ctx_deactivate(), and |
869 | * perf_event_task_tick() are fully serialized because they're strictly cpu | |
870 | * affine and perf_event_ctx{activate,deactivate} are called with IRQs | |
871 | * disabled, while perf_event_task_tick is called from IRQ context. | |
e9d2b064 | 872 | */ |
2fde4f94 | 873 | static void perf_event_ctx_activate(struct perf_event_context *ctx) |
9e35ad38 | 874 | { |
2fde4f94 | 875 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
b5ab4cd5 | 876 | |
e9d2b064 | 877 | WARN_ON(!irqs_disabled()); |
b5ab4cd5 | 878 | |
2fde4f94 MR |
879 | WARN_ON(!list_empty(&ctx->active_ctx_list)); |
880 | ||
881 | list_add(&ctx->active_ctx_list, head); | |
882 | } | |
883 | ||
884 | static void perf_event_ctx_deactivate(struct perf_event_context *ctx) | |
885 | { | |
886 | WARN_ON(!irqs_disabled()); | |
887 | ||
888 | WARN_ON(list_empty(&ctx->active_ctx_list)); | |
889 | ||
890 | list_del_init(&ctx->active_ctx_list); | |
9e35ad38 | 891 | } |
9e35ad38 | 892 | |
cdd6c482 | 893 | static void get_ctx(struct perf_event_context *ctx) |
a63eaf34 | 894 | { |
e5289d4a | 895 | WARN_ON(!atomic_inc_not_zero(&ctx->refcount)); |
a63eaf34 PM |
896 | } |
897 | ||
4af57ef2 YZ |
898 | static void free_ctx(struct rcu_head *head) |
899 | { | |
900 | struct perf_event_context *ctx; | |
901 | ||
902 | ctx = container_of(head, struct perf_event_context, rcu_head); | |
903 | kfree(ctx->task_ctx_data); | |
904 | kfree(ctx); | |
905 | } | |
906 | ||
cdd6c482 | 907 | static void put_ctx(struct perf_event_context *ctx) |
a63eaf34 | 908 | { |
564c2b21 PM |
909 | if (atomic_dec_and_test(&ctx->refcount)) { |
910 | if (ctx->parent_ctx) | |
911 | put_ctx(ctx->parent_ctx); | |
c93f7669 PM |
912 | if (ctx->task) |
913 | put_task_struct(ctx->task); | |
4af57ef2 | 914 | call_rcu(&ctx->rcu_head, free_ctx); |
564c2b21 | 915 | } |
a63eaf34 PM |
916 | } |
917 | ||
f63a8daa PZ |
918 | /* |
919 | * Because of perf_event::ctx migration in sys_perf_event_open::move_group and | |
920 | * perf_pmu_migrate_context() we need some magic. | |
921 | * | |
922 | * Those places that change perf_event::ctx will hold both | |
923 | * perf_event_ctx::mutex of the 'old' and 'new' ctx value. | |
924 | * | |
8b10c5e2 PZ |
925 | * Lock ordering is by mutex address. There are two other sites where |
926 | * perf_event_context::mutex nests and those are: | |
927 | * | |
928 | * - perf_event_exit_task_context() [ child , 0 ] | |
929 | * __perf_event_exit_task() | |
930 | * sync_child_event() | |
931 | * put_event() [ parent, 1 ] | |
932 | * | |
933 | * - perf_event_init_context() [ parent, 0 ] | |
934 | * inherit_task_group() | |
935 | * inherit_group() | |
936 | * inherit_event() | |
937 | * perf_event_alloc() | |
938 | * perf_init_event() | |
939 | * perf_try_init_event() [ child , 1 ] | |
940 | * | |
941 | * While it appears there is an obvious deadlock here -- the parent and child | |
942 | * nesting levels are inverted between the two. This is in fact safe because | |
943 | * life-time rules separate them. That is an exiting task cannot fork, and a | |
944 | * spawning task cannot (yet) exit. | |
945 | * | |
946 | * But remember that that these are parent<->child context relations, and | |
947 | * migration does not affect children, therefore these two orderings should not | |
948 | * interact. | |
f63a8daa PZ |
949 | * |
950 | * The change in perf_event::ctx does not affect children (as claimed above) | |
951 | * because the sys_perf_event_open() case will install a new event and break | |
952 | * the ctx parent<->child relation, and perf_pmu_migrate_context() is only | |
953 | * concerned with cpuctx and that doesn't have children. | |
954 | * | |
955 | * The places that change perf_event::ctx will issue: | |
956 | * | |
957 | * perf_remove_from_context(); | |
958 | * synchronize_rcu(); | |
959 | * perf_install_in_context(); | |
960 | * | |
961 | * to affect the change. The remove_from_context() + synchronize_rcu() should | |
962 | * quiesce the event, after which we can install it in the new location. This | |
963 | * means that only external vectors (perf_fops, prctl) can perturb the event | |
964 | * while in transit. Therefore all such accessors should also acquire | |
965 | * perf_event_context::mutex to serialize against this. | |
966 | * | |
967 | * However; because event->ctx can change while we're waiting to acquire | |
968 | * ctx->mutex we must be careful and use the below perf_event_ctx_lock() | |
969 | * function. | |
970 | * | |
971 | * Lock order: | |
972 | * task_struct::perf_event_mutex | |
973 | * perf_event_context::mutex | |
974 | * perf_event_context::lock | |
975 | * perf_event::child_mutex; | |
976 | * perf_event::mmap_mutex | |
977 | * mmap_sem | |
978 | */ | |
a83fe28e PZ |
979 | static struct perf_event_context * |
980 | perf_event_ctx_lock_nested(struct perf_event *event, int nesting) | |
f63a8daa PZ |
981 | { |
982 | struct perf_event_context *ctx; | |
983 | ||
984 | again: | |
985 | rcu_read_lock(); | |
986 | ctx = ACCESS_ONCE(event->ctx); | |
987 | if (!atomic_inc_not_zero(&ctx->refcount)) { | |
988 | rcu_read_unlock(); | |
989 | goto again; | |
990 | } | |
991 | rcu_read_unlock(); | |
992 | ||
a83fe28e | 993 | mutex_lock_nested(&ctx->mutex, nesting); |
f63a8daa PZ |
994 | if (event->ctx != ctx) { |
995 | mutex_unlock(&ctx->mutex); | |
996 | put_ctx(ctx); | |
997 | goto again; | |
998 | } | |
999 | ||
1000 | return ctx; | |
1001 | } | |
1002 | ||
a83fe28e PZ |
1003 | static inline struct perf_event_context * |
1004 | perf_event_ctx_lock(struct perf_event *event) | |
1005 | { | |
1006 | return perf_event_ctx_lock_nested(event, 0); | |
1007 | } | |
1008 | ||
f63a8daa PZ |
1009 | static void perf_event_ctx_unlock(struct perf_event *event, |
1010 | struct perf_event_context *ctx) | |
1011 | { | |
1012 | mutex_unlock(&ctx->mutex); | |
1013 | put_ctx(ctx); | |
1014 | } | |
1015 | ||
211de6eb PZ |
1016 | /* |
1017 | * This must be done under the ctx->lock, such as to serialize against | |
1018 | * context_equiv(), therefore we cannot call put_ctx() since that might end up | |
1019 | * calling scheduler related locks and ctx->lock nests inside those. | |
1020 | */ | |
1021 | static __must_check struct perf_event_context * | |
1022 | unclone_ctx(struct perf_event_context *ctx) | |
71a851b4 | 1023 | { |
211de6eb PZ |
1024 | struct perf_event_context *parent_ctx = ctx->parent_ctx; |
1025 | ||
1026 | lockdep_assert_held(&ctx->lock); | |
1027 | ||
1028 | if (parent_ctx) | |
71a851b4 | 1029 | ctx->parent_ctx = NULL; |
5a3126d4 | 1030 | ctx->generation++; |
211de6eb PZ |
1031 | |
1032 | return parent_ctx; | |
71a851b4 PZ |
1033 | } |
1034 | ||
6844c09d ACM |
1035 | static u32 perf_event_pid(struct perf_event *event, struct task_struct *p) |
1036 | { | |
1037 | /* | |
1038 | * only top level events have the pid namespace they were created in | |
1039 | */ | |
1040 | if (event->parent) | |
1041 | event = event->parent; | |
1042 | ||
1043 | return task_tgid_nr_ns(p, event->ns); | |
1044 | } | |
1045 | ||
1046 | static u32 perf_event_tid(struct perf_event *event, struct task_struct *p) | |
1047 | { | |
1048 | /* | |
1049 | * only top level events have the pid namespace they were created in | |
1050 | */ | |
1051 | if (event->parent) | |
1052 | event = event->parent; | |
1053 | ||
1054 | return task_pid_nr_ns(p, event->ns); | |
1055 | } | |
1056 | ||
7f453c24 | 1057 | /* |
cdd6c482 | 1058 | * If we inherit events we want to return the parent event id |
7f453c24 PZ |
1059 | * to userspace. |
1060 | */ | |
cdd6c482 | 1061 | static u64 primary_event_id(struct perf_event *event) |
7f453c24 | 1062 | { |
cdd6c482 | 1063 | u64 id = event->id; |
7f453c24 | 1064 | |
cdd6c482 IM |
1065 | if (event->parent) |
1066 | id = event->parent->id; | |
7f453c24 PZ |
1067 | |
1068 | return id; | |
1069 | } | |
1070 | ||
25346b93 | 1071 | /* |
cdd6c482 | 1072 | * Get the perf_event_context for a task and lock it. |
25346b93 PM |
1073 | * This has to cope with with the fact that until it is locked, |
1074 | * the context could get moved to another task. | |
1075 | */ | |
cdd6c482 | 1076 | static struct perf_event_context * |
8dc85d54 | 1077 | perf_lock_task_context(struct task_struct *task, int ctxn, unsigned long *flags) |
25346b93 | 1078 | { |
cdd6c482 | 1079 | struct perf_event_context *ctx; |
25346b93 | 1080 | |
9ed6060d | 1081 | retry: |
058ebd0e PZ |
1082 | /* |
1083 | * One of the few rules of preemptible RCU is that one cannot do | |
1084 | * rcu_read_unlock() while holding a scheduler (or nested) lock when | |
2fd59077 | 1085 | * part of the read side critical section was irqs-enabled -- see |
058ebd0e PZ |
1086 | * rcu_read_unlock_special(). |
1087 | * | |
1088 | * Since ctx->lock nests under rq->lock we must ensure the entire read | |
2fd59077 | 1089 | * side critical section has interrupts disabled. |
058ebd0e | 1090 | */ |
2fd59077 | 1091 | local_irq_save(*flags); |
058ebd0e | 1092 | rcu_read_lock(); |
8dc85d54 | 1093 | ctx = rcu_dereference(task->perf_event_ctxp[ctxn]); |
25346b93 PM |
1094 | if (ctx) { |
1095 | /* | |
1096 | * If this context is a clone of another, it might | |
1097 | * get swapped for another underneath us by | |
cdd6c482 | 1098 | * perf_event_task_sched_out, though the |
25346b93 PM |
1099 | * rcu_read_lock() protects us from any context |
1100 | * getting freed. Lock the context and check if it | |
1101 | * got swapped before we could get the lock, and retry | |
1102 | * if so. If we locked the right context, then it | |
1103 | * can't get swapped on us any more. | |
1104 | */ | |
2fd59077 | 1105 | raw_spin_lock(&ctx->lock); |
8dc85d54 | 1106 | if (ctx != rcu_dereference(task->perf_event_ctxp[ctxn])) { |
2fd59077 | 1107 | raw_spin_unlock(&ctx->lock); |
058ebd0e | 1108 | rcu_read_unlock(); |
2fd59077 | 1109 | local_irq_restore(*flags); |
25346b93 PM |
1110 | goto retry; |
1111 | } | |
b49a9e7e PZ |
1112 | |
1113 | if (!atomic_inc_not_zero(&ctx->refcount)) { | |
2fd59077 | 1114 | raw_spin_unlock(&ctx->lock); |
b49a9e7e PZ |
1115 | ctx = NULL; |
1116 | } | |
25346b93 PM |
1117 | } |
1118 | rcu_read_unlock(); | |
2fd59077 PM |
1119 | if (!ctx) |
1120 | local_irq_restore(*flags); | |
25346b93 PM |
1121 | return ctx; |
1122 | } | |
1123 | ||
1124 | /* | |
1125 | * Get the context for a task and increment its pin_count so it | |
1126 | * can't get swapped to another task. This also increments its | |
1127 | * reference count so that the context can't get freed. | |
1128 | */ | |
8dc85d54 PZ |
1129 | static struct perf_event_context * |
1130 | perf_pin_task_context(struct task_struct *task, int ctxn) | |
25346b93 | 1131 | { |
cdd6c482 | 1132 | struct perf_event_context *ctx; |
25346b93 PM |
1133 | unsigned long flags; |
1134 | ||
8dc85d54 | 1135 | ctx = perf_lock_task_context(task, ctxn, &flags); |
25346b93 PM |
1136 | if (ctx) { |
1137 | ++ctx->pin_count; | |
e625cce1 | 1138 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1139 | } |
1140 | return ctx; | |
1141 | } | |
1142 | ||
cdd6c482 | 1143 | static void perf_unpin_context(struct perf_event_context *ctx) |
25346b93 PM |
1144 | { |
1145 | unsigned long flags; | |
1146 | ||
e625cce1 | 1147 | raw_spin_lock_irqsave(&ctx->lock, flags); |
25346b93 | 1148 | --ctx->pin_count; |
e625cce1 | 1149 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1150 | } |
1151 | ||
f67218c3 PZ |
1152 | /* |
1153 | * Update the record of the current time in a context. | |
1154 | */ | |
1155 | static void update_context_time(struct perf_event_context *ctx) | |
1156 | { | |
1157 | u64 now = perf_clock(); | |
1158 | ||
1159 | ctx->time += now - ctx->timestamp; | |
1160 | ctx->timestamp = now; | |
1161 | } | |
1162 | ||
4158755d SE |
1163 | static u64 perf_event_time(struct perf_event *event) |
1164 | { | |
1165 | struct perf_event_context *ctx = event->ctx; | |
e5d1367f SE |
1166 | |
1167 | if (is_cgroup_event(event)) | |
1168 | return perf_cgroup_event_time(event); | |
1169 | ||
4158755d SE |
1170 | return ctx ? ctx->time : 0; |
1171 | } | |
1172 | ||
f67218c3 PZ |
1173 | /* |
1174 | * Update the total_time_enabled and total_time_running fields for a event. | |
b7526f0c | 1175 | * The caller of this function needs to hold the ctx->lock. |
f67218c3 PZ |
1176 | */ |
1177 | static void update_event_times(struct perf_event *event) | |
1178 | { | |
1179 | struct perf_event_context *ctx = event->ctx; | |
1180 | u64 run_end; | |
1181 | ||
1182 | if (event->state < PERF_EVENT_STATE_INACTIVE || | |
1183 | event->group_leader->state < PERF_EVENT_STATE_INACTIVE) | |
1184 | return; | |
e5d1367f SE |
1185 | /* |
1186 | * in cgroup mode, time_enabled represents | |
1187 | * the time the event was enabled AND active | |
1188 | * tasks were in the monitored cgroup. This is | |
1189 | * independent of the activity of the context as | |
1190 | * there may be a mix of cgroup and non-cgroup events. | |
1191 | * | |
1192 | * That is why we treat cgroup events differently | |
1193 | * here. | |
1194 | */ | |
1195 | if (is_cgroup_event(event)) | |
46cd6a7f | 1196 | run_end = perf_cgroup_event_time(event); |
e5d1367f SE |
1197 | else if (ctx->is_active) |
1198 | run_end = ctx->time; | |
acd1d7c1 PZ |
1199 | else |
1200 | run_end = event->tstamp_stopped; | |
1201 | ||
1202 | event->total_time_enabled = run_end - event->tstamp_enabled; | |
f67218c3 PZ |
1203 | |
1204 | if (event->state == PERF_EVENT_STATE_INACTIVE) | |
1205 | run_end = event->tstamp_stopped; | |
1206 | else | |
4158755d | 1207 | run_end = perf_event_time(event); |
f67218c3 PZ |
1208 | |
1209 | event->total_time_running = run_end - event->tstamp_running; | |
e5d1367f | 1210 | |
f67218c3 PZ |
1211 | } |
1212 | ||
96c21a46 PZ |
1213 | /* |
1214 | * Update total_time_enabled and total_time_running for all events in a group. | |
1215 | */ | |
1216 | static void update_group_times(struct perf_event *leader) | |
1217 | { | |
1218 | struct perf_event *event; | |
1219 | ||
1220 | update_event_times(leader); | |
1221 | list_for_each_entry(event, &leader->sibling_list, group_entry) | |
1222 | update_event_times(event); | |
1223 | } | |
1224 | ||
889ff015 FW |
1225 | static struct list_head * |
1226 | ctx_group_list(struct perf_event *event, struct perf_event_context *ctx) | |
1227 | { | |
1228 | if (event->attr.pinned) | |
1229 | return &ctx->pinned_groups; | |
1230 | else | |
1231 | return &ctx->flexible_groups; | |
1232 | } | |
1233 | ||
fccc714b | 1234 | /* |
cdd6c482 | 1235 | * Add a event from the lists for its context. |
fccc714b PZ |
1236 | * Must be called with ctx->mutex and ctx->lock held. |
1237 | */ | |
04289bb9 | 1238 | static void |
cdd6c482 | 1239 | list_add_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1240 | { |
c994d613 PZ |
1241 | lockdep_assert_held(&ctx->lock); |
1242 | ||
8a49542c PZ |
1243 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); |
1244 | event->attach_state |= PERF_ATTACH_CONTEXT; | |
04289bb9 IM |
1245 | |
1246 | /* | |
8a49542c PZ |
1247 | * If we're a stand alone event or group leader, we go to the context |
1248 | * list, group events are kept attached to the group so that | |
1249 | * perf_group_detach can, at all times, locate all siblings. | |
04289bb9 | 1250 | */ |
8a49542c | 1251 | if (event->group_leader == event) { |
889ff015 FW |
1252 | struct list_head *list; |
1253 | ||
d6f962b5 FW |
1254 | if (is_software_event(event)) |
1255 | event->group_flags |= PERF_GROUP_SOFTWARE; | |
1256 | ||
889ff015 FW |
1257 | list = ctx_group_list(event, ctx); |
1258 | list_add_tail(&event->group_entry, list); | |
5c148194 | 1259 | } |
592903cd | 1260 | |
08309379 | 1261 | if (is_cgroup_event(event)) |
e5d1367f | 1262 | ctx->nr_cgroups++; |
e5d1367f | 1263 | |
cdd6c482 IM |
1264 | list_add_rcu(&event->event_entry, &ctx->event_list); |
1265 | ctx->nr_events++; | |
1266 | if (event->attr.inherit_stat) | |
bfbd3381 | 1267 | ctx->nr_stat++; |
5a3126d4 PZ |
1268 | |
1269 | ctx->generation++; | |
04289bb9 IM |
1270 | } |
1271 | ||
0231bb53 JO |
1272 | /* |
1273 | * Initialize event state based on the perf_event_attr::disabled. | |
1274 | */ | |
1275 | static inline void perf_event__state_init(struct perf_event *event) | |
1276 | { | |
1277 | event->state = event->attr.disabled ? PERF_EVENT_STATE_OFF : | |
1278 | PERF_EVENT_STATE_INACTIVE; | |
1279 | } | |
1280 | ||
a723968c | 1281 | static void __perf_event_read_size(struct perf_event *event, int nr_siblings) |
c320c7b7 ACM |
1282 | { |
1283 | int entry = sizeof(u64); /* value */ | |
1284 | int size = 0; | |
1285 | int nr = 1; | |
1286 | ||
1287 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
1288 | size += sizeof(u64); | |
1289 | ||
1290 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
1291 | size += sizeof(u64); | |
1292 | ||
1293 | if (event->attr.read_format & PERF_FORMAT_ID) | |
1294 | entry += sizeof(u64); | |
1295 | ||
1296 | if (event->attr.read_format & PERF_FORMAT_GROUP) { | |
a723968c | 1297 | nr += nr_siblings; |
c320c7b7 ACM |
1298 | size += sizeof(u64); |
1299 | } | |
1300 | ||
1301 | size += entry * nr; | |
1302 | event->read_size = size; | |
1303 | } | |
1304 | ||
a723968c | 1305 | static void __perf_event_header_size(struct perf_event *event, u64 sample_type) |
c320c7b7 ACM |
1306 | { |
1307 | struct perf_sample_data *data; | |
c320c7b7 ACM |
1308 | u16 size = 0; |
1309 | ||
c320c7b7 ACM |
1310 | if (sample_type & PERF_SAMPLE_IP) |
1311 | size += sizeof(data->ip); | |
1312 | ||
6844c09d ACM |
1313 | if (sample_type & PERF_SAMPLE_ADDR) |
1314 | size += sizeof(data->addr); | |
1315 | ||
1316 | if (sample_type & PERF_SAMPLE_PERIOD) | |
1317 | size += sizeof(data->period); | |
1318 | ||
c3feedf2 AK |
1319 | if (sample_type & PERF_SAMPLE_WEIGHT) |
1320 | size += sizeof(data->weight); | |
1321 | ||
6844c09d ACM |
1322 | if (sample_type & PERF_SAMPLE_READ) |
1323 | size += event->read_size; | |
1324 | ||
d6be9ad6 SE |
1325 | if (sample_type & PERF_SAMPLE_DATA_SRC) |
1326 | size += sizeof(data->data_src.val); | |
1327 | ||
fdfbbd07 AK |
1328 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
1329 | size += sizeof(data->txn); | |
1330 | ||
6844c09d ACM |
1331 | event->header_size = size; |
1332 | } | |
1333 | ||
a723968c PZ |
1334 | /* |
1335 | * Called at perf_event creation and when events are attached/detached from a | |
1336 | * group. | |
1337 | */ | |
1338 | static void perf_event__header_size(struct perf_event *event) | |
1339 | { | |
1340 | __perf_event_read_size(event, | |
1341 | event->group_leader->nr_siblings); | |
1342 | __perf_event_header_size(event, event->attr.sample_type); | |
1343 | } | |
1344 | ||
6844c09d ACM |
1345 | static void perf_event__id_header_size(struct perf_event *event) |
1346 | { | |
1347 | struct perf_sample_data *data; | |
1348 | u64 sample_type = event->attr.sample_type; | |
1349 | u16 size = 0; | |
1350 | ||
c320c7b7 ACM |
1351 | if (sample_type & PERF_SAMPLE_TID) |
1352 | size += sizeof(data->tid_entry); | |
1353 | ||
1354 | if (sample_type & PERF_SAMPLE_TIME) | |
1355 | size += sizeof(data->time); | |
1356 | ||
ff3d527c AH |
1357 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
1358 | size += sizeof(data->id); | |
1359 | ||
c320c7b7 ACM |
1360 | if (sample_type & PERF_SAMPLE_ID) |
1361 | size += sizeof(data->id); | |
1362 | ||
1363 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
1364 | size += sizeof(data->stream_id); | |
1365 | ||
1366 | if (sample_type & PERF_SAMPLE_CPU) | |
1367 | size += sizeof(data->cpu_entry); | |
1368 | ||
6844c09d | 1369 | event->id_header_size = size; |
c320c7b7 ACM |
1370 | } |
1371 | ||
a723968c PZ |
1372 | static bool perf_event_validate_size(struct perf_event *event) |
1373 | { | |
1374 | /* | |
1375 | * The values computed here will be over-written when we actually | |
1376 | * attach the event. | |
1377 | */ | |
1378 | __perf_event_read_size(event, event->group_leader->nr_siblings + 1); | |
1379 | __perf_event_header_size(event, event->attr.sample_type & ~PERF_SAMPLE_READ); | |
1380 | perf_event__id_header_size(event); | |
1381 | ||
1382 | /* | |
1383 | * Sum the lot; should not exceed the 64k limit we have on records. | |
1384 | * Conservative limit to allow for callchains and other variable fields. | |
1385 | */ | |
1386 | if (event->read_size + event->header_size + | |
1387 | event->id_header_size + sizeof(struct perf_event_header) >= 16*1024) | |
1388 | return false; | |
1389 | ||
1390 | return true; | |
1391 | } | |
1392 | ||
8a49542c PZ |
1393 | static void perf_group_attach(struct perf_event *event) |
1394 | { | |
c320c7b7 | 1395 | struct perf_event *group_leader = event->group_leader, *pos; |
8a49542c | 1396 | |
74c3337c PZ |
1397 | /* |
1398 | * We can have double attach due to group movement in perf_event_open. | |
1399 | */ | |
1400 | if (event->attach_state & PERF_ATTACH_GROUP) | |
1401 | return; | |
1402 | ||
8a49542c PZ |
1403 | event->attach_state |= PERF_ATTACH_GROUP; |
1404 | ||
1405 | if (group_leader == event) | |
1406 | return; | |
1407 | ||
652884fe PZ |
1408 | WARN_ON_ONCE(group_leader->ctx != event->ctx); |
1409 | ||
8a49542c PZ |
1410 | if (group_leader->group_flags & PERF_GROUP_SOFTWARE && |
1411 | !is_software_event(event)) | |
1412 | group_leader->group_flags &= ~PERF_GROUP_SOFTWARE; | |
1413 | ||
1414 | list_add_tail(&event->group_entry, &group_leader->sibling_list); | |
1415 | group_leader->nr_siblings++; | |
c320c7b7 ACM |
1416 | |
1417 | perf_event__header_size(group_leader); | |
1418 | ||
1419 | list_for_each_entry(pos, &group_leader->sibling_list, group_entry) | |
1420 | perf_event__header_size(pos); | |
8a49542c PZ |
1421 | } |
1422 | ||
a63eaf34 | 1423 | /* |
cdd6c482 | 1424 | * Remove a event from the lists for its context. |
fccc714b | 1425 | * Must be called with ctx->mutex and ctx->lock held. |
a63eaf34 | 1426 | */ |
04289bb9 | 1427 | static void |
cdd6c482 | 1428 | list_del_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1429 | { |
68cacd29 | 1430 | struct perf_cpu_context *cpuctx; |
652884fe PZ |
1431 | |
1432 | WARN_ON_ONCE(event->ctx != ctx); | |
1433 | lockdep_assert_held(&ctx->lock); | |
1434 | ||
8a49542c PZ |
1435 | /* |
1436 | * We can have double detach due to exit/hot-unplug + close. | |
1437 | */ | |
1438 | if (!(event->attach_state & PERF_ATTACH_CONTEXT)) | |
a63eaf34 | 1439 | return; |
8a49542c PZ |
1440 | |
1441 | event->attach_state &= ~PERF_ATTACH_CONTEXT; | |
1442 | ||
68cacd29 | 1443 | if (is_cgroup_event(event)) { |
e5d1367f | 1444 | ctx->nr_cgroups--; |
70a01657 PZ |
1445 | /* |
1446 | * Because cgroup events are always per-cpu events, this will | |
1447 | * always be called from the right CPU. | |
1448 | */ | |
68cacd29 SE |
1449 | cpuctx = __get_cpu_context(ctx); |
1450 | /* | |
70a01657 PZ |
1451 | * If there are no more cgroup events then clear cgrp to avoid |
1452 | * stale pointer in update_cgrp_time_from_cpuctx(). | |
68cacd29 SE |
1453 | */ |
1454 | if (!ctx->nr_cgroups) | |
1455 | cpuctx->cgrp = NULL; | |
1456 | } | |
e5d1367f | 1457 | |
cdd6c482 IM |
1458 | ctx->nr_events--; |
1459 | if (event->attr.inherit_stat) | |
bfbd3381 | 1460 | ctx->nr_stat--; |
8bc20959 | 1461 | |
cdd6c482 | 1462 | list_del_rcu(&event->event_entry); |
04289bb9 | 1463 | |
8a49542c PZ |
1464 | if (event->group_leader == event) |
1465 | list_del_init(&event->group_entry); | |
5c148194 | 1466 | |
96c21a46 | 1467 | update_group_times(event); |
b2e74a26 SE |
1468 | |
1469 | /* | |
1470 | * If event was in error state, then keep it | |
1471 | * that way, otherwise bogus counts will be | |
1472 | * returned on read(). The only way to get out | |
1473 | * of error state is by explicit re-enabling | |
1474 | * of the event | |
1475 | */ | |
1476 | if (event->state > PERF_EVENT_STATE_OFF) | |
1477 | event->state = PERF_EVENT_STATE_OFF; | |
5a3126d4 PZ |
1478 | |
1479 | ctx->generation++; | |
050735b0 PZ |
1480 | } |
1481 | ||
8a49542c | 1482 | static void perf_group_detach(struct perf_event *event) |
050735b0 PZ |
1483 | { |
1484 | struct perf_event *sibling, *tmp; | |
8a49542c PZ |
1485 | struct list_head *list = NULL; |
1486 | ||
1487 | /* | |
1488 | * We can have double detach due to exit/hot-unplug + close. | |
1489 | */ | |
1490 | if (!(event->attach_state & PERF_ATTACH_GROUP)) | |
1491 | return; | |
1492 | ||
1493 | event->attach_state &= ~PERF_ATTACH_GROUP; | |
1494 | ||
1495 | /* | |
1496 | * If this is a sibling, remove it from its group. | |
1497 | */ | |
1498 | if (event->group_leader != event) { | |
1499 | list_del_init(&event->group_entry); | |
1500 | event->group_leader->nr_siblings--; | |
c320c7b7 | 1501 | goto out; |
8a49542c PZ |
1502 | } |
1503 | ||
1504 | if (!list_empty(&event->group_entry)) | |
1505 | list = &event->group_entry; | |
2e2af50b | 1506 | |
04289bb9 | 1507 | /* |
cdd6c482 IM |
1508 | * If this was a group event with sibling events then |
1509 | * upgrade the siblings to singleton events by adding them | |
8a49542c | 1510 | * to whatever list we are on. |
04289bb9 | 1511 | */ |
cdd6c482 | 1512 | list_for_each_entry_safe(sibling, tmp, &event->sibling_list, group_entry) { |
8a49542c PZ |
1513 | if (list) |
1514 | list_move_tail(&sibling->group_entry, list); | |
04289bb9 | 1515 | sibling->group_leader = sibling; |
d6f962b5 FW |
1516 | |
1517 | /* Inherit group flags from the previous leader */ | |
1518 | sibling->group_flags = event->group_flags; | |
652884fe PZ |
1519 | |
1520 | WARN_ON_ONCE(sibling->ctx != event->ctx); | |
04289bb9 | 1521 | } |
c320c7b7 ACM |
1522 | |
1523 | out: | |
1524 | perf_event__header_size(event->group_leader); | |
1525 | ||
1526 | list_for_each_entry(tmp, &event->group_leader->sibling_list, group_entry) | |
1527 | perf_event__header_size(tmp); | |
04289bb9 IM |
1528 | } |
1529 | ||
fadfe7be JO |
1530 | /* |
1531 | * User event without the task. | |
1532 | */ | |
1533 | static bool is_orphaned_event(struct perf_event *event) | |
1534 | { | |
1535 | return event && !is_kernel_event(event) && !event->owner; | |
1536 | } | |
1537 | ||
1538 | /* | |
1539 | * Event has a parent but parent's task finished and it's | |
1540 | * alive only because of children holding refference. | |
1541 | */ | |
1542 | static bool is_orphaned_child(struct perf_event *event) | |
1543 | { | |
1544 | return is_orphaned_event(event->parent); | |
1545 | } | |
1546 | ||
1547 | static void orphans_remove_work(struct work_struct *work); | |
1548 | ||
1549 | static void schedule_orphans_remove(struct perf_event_context *ctx) | |
1550 | { | |
1551 | if (!ctx->task || ctx->orphans_remove_sched || !perf_wq) | |
1552 | return; | |
1553 | ||
1554 | if (queue_delayed_work(perf_wq, &ctx->orphans_remove, 1)) { | |
1555 | get_ctx(ctx); | |
1556 | ctx->orphans_remove_sched = true; | |
1557 | } | |
1558 | } | |
1559 | ||
1560 | static int __init perf_workqueue_init(void) | |
1561 | { | |
1562 | perf_wq = create_singlethread_workqueue("perf"); | |
1563 | WARN(!perf_wq, "failed to create perf workqueue\n"); | |
1564 | return perf_wq ? 0 : -1; | |
1565 | } | |
1566 | ||
1567 | core_initcall(perf_workqueue_init); | |
1568 | ||
66eb579e MR |
1569 | static inline int pmu_filter_match(struct perf_event *event) |
1570 | { | |
1571 | struct pmu *pmu = event->pmu; | |
1572 | return pmu->filter_match ? pmu->filter_match(event) : 1; | |
1573 | } | |
1574 | ||
fa66f07a SE |
1575 | static inline int |
1576 | event_filter_match(struct perf_event *event) | |
1577 | { | |
e5d1367f | 1578 | return (event->cpu == -1 || event->cpu == smp_processor_id()) |
66eb579e | 1579 | && perf_cgroup_match(event) && pmu_filter_match(event); |
fa66f07a SE |
1580 | } |
1581 | ||
9ffcfa6f SE |
1582 | static void |
1583 | event_sched_out(struct perf_event *event, | |
3b6f9e5c | 1584 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 1585 | struct perf_event_context *ctx) |
3b6f9e5c | 1586 | { |
4158755d | 1587 | u64 tstamp = perf_event_time(event); |
fa66f07a | 1588 | u64 delta; |
652884fe PZ |
1589 | |
1590 | WARN_ON_ONCE(event->ctx != ctx); | |
1591 | lockdep_assert_held(&ctx->lock); | |
1592 | ||
fa66f07a SE |
1593 | /* |
1594 | * An event which could not be activated because of | |
1595 | * filter mismatch still needs to have its timings | |
1596 | * maintained, otherwise bogus information is return | |
1597 | * via read() for time_enabled, time_running: | |
1598 | */ | |
1599 | if (event->state == PERF_EVENT_STATE_INACTIVE | |
1600 | && !event_filter_match(event)) { | |
e5d1367f | 1601 | delta = tstamp - event->tstamp_stopped; |
fa66f07a | 1602 | event->tstamp_running += delta; |
4158755d | 1603 | event->tstamp_stopped = tstamp; |
fa66f07a SE |
1604 | } |
1605 | ||
cdd6c482 | 1606 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
9ffcfa6f | 1607 | return; |
3b6f9e5c | 1608 | |
44377277 AS |
1609 | perf_pmu_disable(event->pmu); |
1610 | ||
cdd6c482 IM |
1611 | event->state = PERF_EVENT_STATE_INACTIVE; |
1612 | if (event->pending_disable) { | |
1613 | event->pending_disable = 0; | |
1614 | event->state = PERF_EVENT_STATE_OFF; | |
970892a9 | 1615 | } |
4158755d | 1616 | event->tstamp_stopped = tstamp; |
a4eaf7f1 | 1617 | event->pmu->del(event, 0); |
cdd6c482 | 1618 | event->oncpu = -1; |
3b6f9e5c | 1619 | |
cdd6c482 | 1620 | if (!is_software_event(event)) |
3b6f9e5c | 1621 | cpuctx->active_oncpu--; |
2fde4f94 MR |
1622 | if (!--ctx->nr_active) |
1623 | perf_event_ctx_deactivate(ctx); | |
0f5a2601 PZ |
1624 | if (event->attr.freq && event->attr.sample_freq) |
1625 | ctx->nr_freq--; | |
cdd6c482 | 1626 | if (event->attr.exclusive || !cpuctx->active_oncpu) |
3b6f9e5c | 1627 | cpuctx->exclusive = 0; |
44377277 | 1628 | |
fadfe7be JO |
1629 | if (is_orphaned_child(event)) |
1630 | schedule_orphans_remove(ctx); | |
1631 | ||
44377277 | 1632 | perf_pmu_enable(event->pmu); |
3b6f9e5c PM |
1633 | } |
1634 | ||
d859e29f | 1635 | static void |
cdd6c482 | 1636 | group_sched_out(struct perf_event *group_event, |
d859e29f | 1637 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 1638 | struct perf_event_context *ctx) |
d859e29f | 1639 | { |
cdd6c482 | 1640 | struct perf_event *event; |
fa66f07a | 1641 | int state = group_event->state; |
d859e29f | 1642 | |
cdd6c482 | 1643 | event_sched_out(group_event, cpuctx, ctx); |
d859e29f PM |
1644 | |
1645 | /* | |
1646 | * Schedule out siblings (if any): | |
1647 | */ | |
cdd6c482 IM |
1648 | list_for_each_entry(event, &group_event->sibling_list, group_entry) |
1649 | event_sched_out(event, cpuctx, ctx); | |
d859e29f | 1650 | |
fa66f07a | 1651 | if (state == PERF_EVENT_STATE_ACTIVE && group_event->attr.exclusive) |
d859e29f PM |
1652 | cpuctx->exclusive = 0; |
1653 | } | |
1654 | ||
46ce0fe9 PZ |
1655 | struct remove_event { |
1656 | struct perf_event *event; | |
1657 | bool detach_group; | |
1658 | }; | |
1659 | ||
0017960f PZ |
1660 | static void ___perf_remove_from_context(void *info) |
1661 | { | |
1662 | struct remove_event *re = info; | |
1663 | struct perf_event *event = re->event; | |
1664 | struct perf_event_context *ctx = event->ctx; | |
1665 | ||
1666 | if (re->detach_group) | |
1667 | perf_group_detach(event); | |
1668 | list_del_event(event, ctx); | |
1669 | } | |
1670 | ||
0793a61d | 1671 | /* |
cdd6c482 | 1672 | * Cross CPU call to remove a performance event |
0793a61d | 1673 | * |
cdd6c482 | 1674 | * We disable the event on the hardware level first. After that we |
0793a61d TG |
1675 | * remove it from the context list. |
1676 | */ | |
fe4b04fa | 1677 | static int __perf_remove_from_context(void *info) |
0793a61d | 1678 | { |
46ce0fe9 PZ |
1679 | struct remove_event *re = info; |
1680 | struct perf_event *event = re->event; | |
cdd6c482 | 1681 | struct perf_event_context *ctx = event->ctx; |
108b02cf | 1682 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
0793a61d | 1683 | |
e625cce1 | 1684 | raw_spin_lock(&ctx->lock); |
cdd6c482 | 1685 | event_sched_out(event, cpuctx, ctx); |
46ce0fe9 PZ |
1686 | if (re->detach_group) |
1687 | perf_group_detach(event); | |
cdd6c482 | 1688 | list_del_event(event, ctx); |
64ce3126 PZ |
1689 | if (!ctx->nr_events && cpuctx->task_ctx == ctx) { |
1690 | ctx->is_active = 0; | |
1691 | cpuctx->task_ctx = NULL; | |
1692 | } | |
e625cce1 | 1693 | raw_spin_unlock(&ctx->lock); |
fe4b04fa PZ |
1694 | |
1695 | return 0; | |
0793a61d TG |
1696 | } |
1697 | ||
0793a61d | 1698 | /* |
cdd6c482 | 1699 | * Remove the event from a task's (or a CPU's) list of events. |
0793a61d | 1700 | * |
cdd6c482 | 1701 | * CPU events are removed with a smp call. For task events we only |
0793a61d | 1702 | * call when the task is on a CPU. |
c93f7669 | 1703 | * |
cdd6c482 IM |
1704 | * If event->ctx is a cloned context, callers must make sure that |
1705 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 PM |
1706 | * remains valid. This is OK when called from perf_release since |
1707 | * that only calls us on the top-level context, which can't be a clone. | |
cdd6c482 | 1708 | * When called from perf_event_exit_task, it's OK because the |
c93f7669 | 1709 | * context has been detached from its task. |
0793a61d | 1710 | */ |
46ce0fe9 | 1711 | static void perf_remove_from_context(struct perf_event *event, bool detach_group) |
0793a61d | 1712 | { |
cdd6c482 | 1713 | struct perf_event_context *ctx = event->ctx; |
46ce0fe9 PZ |
1714 | struct remove_event re = { |
1715 | .event = event, | |
1716 | .detach_group = detach_group, | |
1717 | }; | |
0793a61d | 1718 | |
fe4b04fa PZ |
1719 | lockdep_assert_held(&ctx->mutex); |
1720 | ||
0017960f PZ |
1721 | event_function_call(event, __perf_remove_from_context, |
1722 | ___perf_remove_from_context, &re); | |
0793a61d TG |
1723 | } |
1724 | ||
d859e29f | 1725 | /* |
cdd6c482 | 1726 | * Cross CPU call to disable a performance event |
d859e29f | 1727 | */ |
500ad2d8 | 1728 | int __perf_event_disable(void *info) |
d859e29f | 1729 | { |
cdd6c482 | 1730 | struct perf_event *event = info; |
cdd6c482 | 1731 | struct perf_event_context *ctx = event->ctx; |
108b02cf | 1732 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
d859e29f PM |
1733 | |
1734 | /* | |
cdd6c482 IM |
1735 | * If this is a per-task event, need to check whether this |
1736 | * event's task is the current task on this cpu. | |
fe4b04fa PZ |
1737 | * |
1738 | * Can trigger due to concurrent perf_event_context_sched_out() | |
1739 | * flipping contexts around. | |
d859e29f | 1740 | */ |
665c2142 | 1741 | if (ctx->task && cpuctx->task_ctx != ctx) |
fe4b04fa | 1742 | return -EINVAL; |
d859e29f | 1743 | |
e625cce1 | 1744 | raw_spin_lock(&ctx->lock); |
d859e29f PM |
1745 | |
1746 | /* | |
cdd6c482 | 1747 | * If the event is on, turn it off. |
d859e29f PM |
1748 | * If it is in error state, leave it in error state. |
1749 | */ | |
cdd6c482 | 1750 | if (event->state >= PERF_EVENT_STATE_INACTIVE) { |
4af4998b | 1751 | update_context_time(ctx); |
e5d1367f | 1752 | update_cgrp_time_from_event(event); |
cdd6c482 IM |
1753 | update_group_times(event); |
1754 | if (event == event->group_leader) | |
1755 | group_sched_out(event, cpuctx, ctx); | |
d859e29f | 1756 | else |
cdd6c482 IM |
1757 | event_sched_out(event, cpuctx, ctx); |
1758 | event->state = PERF_EVENT_STATE_OFF; | |
d859e29f PM |
1759 | } |
1760 | ||
e625cce1 | 1761 | raw_spin_unlock(&ctx->lock); |
fe4b04fa PZ |
1762 | |
1763 | return 0; | |
d859e29f PM |
1764 | } |
1765 | ||
7b648018 PZ |
1766 | void ___perf_event_disable(void *info) |
1767 | { | |
1768 | struct perf_event *event = info; | |
1769 | ||
1770 | /* | |
1771 | * Since we have the lock this context can't be scheduled | |
1772 | * in, so we can change the state safely. | |
1773 | */ | |
1774 | if (event->state == PERF_EVENT_STATE_INACTIVE) { | |
1775 | update_group_times(event); | |
1776 | event->state = PERF_EVENT_STATE_OFF; | |
1777 | } | |
1778 | } | |
1779 | ||
d859e29f | 1780 | /* |
cdd6c482 | 1781 | * Disable a event. |
c93f7669 | 1782 | * |
cdd6c482 IM |
1783 | * If event->ctx is a cloned context, callers must make sure that |
1784 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 1785 | * remains valid. This condition is satisifed when called through |
cdd6c482 IM |
1786 | * perf_event_for_each_child or perf_event_for_each because they |
1787 | * hold the top-level event's child_mutex, so any descendant that | |
1788 | * goes to exit will block in sync_child_event. | |
1789 | * When called from perf_pending_event it's OK because event->ctx | |
c93f7669 | 1790 | * is the current context on this CPU and preemption is disabled, |
cdd6c482 | 1791 | * hence we can't get into perf_event_task_sched_out for this context. |
d859e29f | 1792 | */ |
f63a8daa | 1793 | static void _perf_event_disable(struct perf_event *event) |
d859e29f | 1794 | { |
cdd6c482 | 1795 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 1796 | |
e625cce1 | 1797 | raw_spin_lock_irq(&ctx->lock); |
7b648018 | 1798 | if (event->state <= PERF_EVENT_STATE_OFF) { |
e625cce1 | 1799 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 1800 | return; |
53cfbf59 | 1801 | } |
e625cce1 | 1802 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 PZ |
1803 | |
1804 | event_function_call(event, __perf_event_disable, | |
1805 | ___perf_event_disable, event); | |
d859e29f | 1806 | } |
f63a8daa PZ |
1807 | |
1808 | /* | |
1809 | * Strictly speaking kernel users cannot create groups and therefore this | |
1810 | * interface does not need the perf_event_ctx_lock() magic. | |
1811 | */ | |
1812 | void perf_event_disable(struct perf_event *event) | |
1813 | { | |
1814 | struct perf_event_context *ctx; | |
1815 | ||
1816 | ctx = perf_event_ctx_lock(event); | |
1817 | _perf_event_disable(event); | |
1818 | perf_event_ctx_unlock(event, ctx); | |
1819 | } | |
dcfce4a0 | 1820 | EXPORT_SYMBOL_GPL(perf_event_disable); |
d859e29f | 1821 | |
e5d1367f SE |
1822 | static void perf_set_shadow_time(struct perf_event *event, |
1823 | struct perf_event_context *ctx, | |
1824 | u64 tstamp) | |
1825 | { | |
1826 | /* | |
1827 | * use the correct time source for the time snapshot | |
1828 | * | |
1829 | * We could get by without this by leveraging the | |
1830 | * fact that to get to this function, the caller | |
1831 | * has most likely already called update_context_time() | |
1832 | * and update_cgrp_time_xx() and thus both timestamp | |
1833 | * are identical (or very close). Given that tstamp is, | |
1834 | * already adjusted for cgroup, we could say that: | |
1835 | * tstamp - ctx->timestamp | |
1836 | * is equivalent to | |
1837 | * tstamp - cgrp->timestamp. | |
1838 | * | |
1839 | * Then, in perf_output_read(), the calculation would | |
1840 | * work with no changes because: | |
1841 | * - event is guaranteed scheduled in | |
1842 | * - no scheduled out in between | |
1843 | * - thus the timestamp would be the same | |
1844 | * | |
1845 | * But this is a bit hairy. | |
1846 | * | |
1847 | * So instead, we have an explicit cgroup call to remain | |
1848 | * within the time time source all along. We believe it | |
1849 | * is cleaner and simpler to understand. | |
1850 | */ | |
1851 | if (is_cgroup_event(event)) | |
1852 | perf_cgroup_set_shadow_time(event, tstamp); | |
1853 | else | |
1854 | event->shadow_ctx_time = tstamp - ctx->timestamp; | |
1855 | } | |
1856 | ||
4fe757dd PZ |
1857 | #define MAX_INTERRUPTS (~0ULL) |
1858 | ||
1859 | static void perf_log_throttle(struct perf_event *event, int enable); | |
ec0d7729 | 1860 | static void perf_log_itrace_start(struct perf_event *event); |
4fe757dd | 1861 | |
235c7fc7 | 1862 | static int |
9ffcfa6f | 1863 | event_sched_in(struct perf_event *event, |
235c7fc7 | 1864 | struct perf_cpu_context *cpuctx, |
6e37738a | 1865 | struct perf_event_context *ctx) |
235c7fc7 | 1866 | { |
4158755d | 1867 | u64 tstamp = perf_event_time(event); |
44377277 | 1868 | int ret = 0; |
4158755d | 1869 | |
63342411 PZ |
1870 | lockdep_assert_held(&ctx->lock); |
1871 | ||
cdd6c482 | 1872 | if (event->state <= PERF_EVENT_STATE_OFF) |
235c7fc7 IM |
1873 | return 0; |
1874 | ||
cdd6c482 | 1875 | event->state = PERF_EVENT_STATE_ACTIVE; |
6e37738a | 1876 | event->oncpu = smp_processor_id(); |
4fe757dd PZ |
1877 | |
1878 | /* | |
1879 | * Unthrottle events, since we scheduled we might have missed several | |
1880 | * ticks already, also for a heavily scheduling task there is little | |
1881 | * guarantee it'll get a tick in a timely manner. | |
1882 | */ | |
1883 | if (unlikely(event->hw.interrupts == MAX_INTERRUPTS)) { | |
1884 | perf_log_throttle(event, 1); | |
1885 | event->hw.interrupts = 0; | |
1886 | } | |
1887 | ||
235c7fc7 IM |
1888 | /* |
1889 | * The new state must be visible before we turn it on in the hardware: | |
1890 | */ | |
1891 | smp_wmb(); | |
1892 | ||
44377277 AS |
1893 | perf_pmu_disable(event->pmu); |
1894 | ||
72f669c0 SL |
1895 | perf_set_shadow_time(event, ctx, tstamp); |
1896 | ||
ec0d7729 AS |
1897 | perf_log_itrace_start(event); |
1898 | ||
a4eaf7f1 | 1899 | if (event->pmu->add(event, PERF_EF_START)) { |
cdd6c482 IM |
1900 | event->state = PERF_EVENT_STATE_INACTIVE; |
1901 | event->oncpu = -1; | |
44377277 AS |
1902 | ret = -EAGAIN; |
1903 | goto out; | |
235c7fc7 IM |
1904 | } |
1905 | ||
00a2916f PZ |
1906 | event->tstamp_running += tstamp - event->tstamp_stopped; |
1907 | ||
cdd6c482 | 1908 | if (!is_software_event(event)) |
3b6f9e5c | 1909 | cpuctx->active_oncpu++; |
2fde4f94 MR |
1910 | if (!ctx->nr_active++) |
1911 | perf_event_ctx_activate(ctx); | |
0f5a2601 PZ |
1912 | if (event->attr.freq && event->attr.sample_freq) |
1913 | ctx->nr_freq++; | |
235c7fc7 | 1914 | |
cdd6c482 | 1915 | if (event->attr.exclusive) |
3b6f9e5c PM |
1916 | cpuctx->exclusive = 1; |
1917 | ||
fadfe7be JO |
1918 | if (is_orphaned_child(event)) |
1919 | schedule_orphans_remove(ctx); | |
1920 | ||
44377277 AS |
1921 | out: |
1922 | perf_pmu_enable(event->pmu); | |
1923 | ||
1924 | return ret; | |
235c7fc7 IM |
1925 | } |
1926 | ||
6751b71e | 1927 | static int |
cdd6c482 | 1928 | group_sched_in(struct perf_event *group_event, |
6751b71e | 1929 | struct perf_cpu_context *cpuctx, |
6e37738a | 1930 | struct perf_event_context *ctx) |
6751b71e | 1931 | { |
6bde9b6c | 1932 | struct perf_event *event, *partial_group = NULL; |
4a234593 | 1933 | struct pmu *pmu = ctx->pmu; |
d7842da4 SE |
1934 | u64 now = ctx->time; |
1935 | bool simulate = false; | |
6751b71e | 1936 | |
cdd6c482 | 1937 | if (group_event->state == PERF_EVENT_STATE_OFF) |
6751b71e PM |
1938 | return 0; |
1939 | ||
fbbe0701 | 1940 | pmu->start_txn(pmu, PERF_PMU_TXN_ADD); |
6bde9b6c | 1941 | |
9ffcfa6f | 1942 | if (event_sched_in(group_event, cpuctx, ctx)) { |
ad5133b7 | 1943 | pmu->cancel_txn(pmu); |
272325c4 | 1944 | perf_mux_hrtimer_restart(cpuctx); |
6751b71e | 1945 | return -EAGAIN; |
90151c35 | 1946 | } |
6751b71e PM |
1947 | |
1948 | /* | |
1949 | * Schedule in siblings as one group (if any): | |
1950 | */ | |
cdd6c482 | 1951 | list_for_each_entry(event, &group_event->sibling_list, group_entry) { |
9ffcfa6f | 1952 | if (event_sched_in(event, cpuctx, ctx)) { |
cdd6c482 | 1953 | partial_group = event; |
6751b71e PM |
1954 | goto group_error; |
1955 | } | |
1956 | } | |
1957 | ||
9ffcfa6f | 1958 | if (!pmu->commit_txn(pmu)) |
6e85158c | 1959 | return 0; |
9ffcfa6f | 1960 | |
6751b71e PM |
1961 | group_error: |
1962 | /* | |
1963 | * Groups can be scheduled in as one unit only, so undo any | |
1964 | * partial group before returning: | |
d7842da4 SE |
1965 | * The events up to the failed event are scheduled out normally, |
1966 | * tstamp_stopped will be updated. | |
1967 | * | |
1968 | * The failed events and the remaining siblings need to have | |
1969 | * their timings updated as if they had gone thru event_sched_in() | |
1970 | * and event_sched_out(). This is required to get consistent timings | |
1971 | * across the group. This also takes care of the case where the group | |
1972 | * could never be scheduled by ensuring tstamp_stopped is set to mark | |
1973 | * the time the event was actually stopped, such that time delta | |
1974 | * calculation in update_event_times() is correct. | |
6751b71e | 1975 | */ |
cdd6c482 IM |
1976 | list_for_each_entry(event, &group_event->sibling_list, group_entry) { |
1977 | if (event == partial_group) | |
d7842da4 SE |
1978 | simulate = true; |
1979 | ||
1980 | if (simulate) { | |
1981 | event->tstamp_running += now - event->tstamp_stopped; | |
1982 | event->tstamp_stopped = now; | |
1983 | } else { | |
1984 | event_sched_out(event, cpuctx, ctx); | |
1985 | } | |
6751b71e | 1986 | } |
9ffcfa6f | 1987 | event_sched_out(group_event, cpuctx, ctx); |
6751b71e | 1988 | |
ad5133b7 | 1989 | pmu->cancel_txn(pmu); |
90151c35 | 1990 | |
272325c4 | 1991 | perf_mux_hrtimer_restart(cpuctx); |
9e630205 | 1992 | |
6751b71e PM |
1993 | return -EAGAIN; |
1994 | } | |
1995 | ||
3b6f9e5c | 1996 | /* |
cdd6c482 | 1997 | * Work out whether we can put this event group on the CPU now. |
3b6f9e5c | 1998 | */ |
cdd6c482 | 1999 | static int group_can_go_on(struct perf_event *event, |
3b6f9e5c PM |
2000 | struct perf_cpu_context *cpuctx, |
2001 | int can_add_hw) | |
2002 | { | |
2003 | /* | |
cdd6c482 | 2004 | * Groups consisting entirely of software events can always go on. |
3b6f9e5c | 2005 | */ |
d6f962b5 | 2006 | if (event->group_flags & PERF_GROUP_SOFTWARE) |
3b6f9e5c PM |
2007 | return 1; |
2008 | /* | |
2009 | * If an exclusive group is already on, no other hardware | |
cdd6c482 | 2010 | * events can go on. |
3b6f9e5c PM |
2011 | */ |
2012 | if (cpuctx->exclusive) | |
2013 | return 0; | |
2014 | /* | |
2015 | * If this group is exclusive and there are already | |
cdd6c482 | 2016 | * events on the CPU, it can't go on. |
3b6f9e5c | 2017 | */ |
cdd6c482 | 2018 | if (event->attr.exclusive && cpuctx->active_oncpu) |
3b6f9e5c PM |
2019 | return 0; |
2020 | /* | |
2021 | * Otherwise, try to add it if all previous groups were able | |
2022 | * to go on. | |
2023 | */ | |
2024 | return can_add_hw; | |
2025 | } | |
2026 | ||
cdd6c482 IM |
2027 | static void add_event_to_ctx(struct perf_event *event, |
2028 | struct perf_event_context *ctx) | |
53cfbf59 | 2029 | { |
4158755d SE |
2030 | u64 tstamp = perf_event_time(event); |
2031 | ||
cdd6c482 | 2032 | list_add_event(event, ctx); |
8a49542c | 2033 | perf_group_attach(event); |
4158755d SE |
2034 | event->tstamp_enabled = tstamp; |
2035 | event->tstamp_running = tstamp; | |
2036 | event->tstamp_stopped = tstamp; | |
53cfbf59 PM |
2037 | } |
2038 | ||
2c29ef0f PZ |
2039 | static void task_ctx_sched_out(struct perf_event_context *ctx); |
2040 | static void | |
2041 | ctx_sched_in(struct perf_event_context *ctx, | |
2042 | struct perf_cpu_context *cpuctx, | |
2043 | enum event_type_t event_type, | |
2044 | struct task_struct *task); | |
fe4b04fa | 2045 | |
dce5855b PZ |
2046 | static void perf_event_sched_in(struct perf_cpu_context *cpuctx, |
2047 | struct perf_event_context *ctx, | |
2048 | struct task_struct *task) | |
2049 | { | |
2050 | cpu_ctx_sched_in(cpuctx, EVENT_PINNED, task); | |
2051 | if (ctx) | |
2052 | ctx_sched_in(ctx, cpuctx, EVENT_PINNED, task); | |
2053 | cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE, task); | |
2054 | if (ctx) | |
2055 | ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE, task); | |
2056 | } | |
2057 | ||
0017960f PZ |
2058 | static void ___perf_install_in_context(void *info) |
2059 | { | |
2060 | struct perf_event *event = info; | |
2061 | struct perf_event_context *ctx = event->ctx; | |
2062 | ||
2063 | /* | |
2064 | * Since the task isn't running, its safe to add the event, us holding | |
2065 | * the ctx->lock ensures the task won't get scheduled in. | |
2066 | */ | |
2067 | add_event_to_ctx(event, ctx); | |
2068 | } | |
2069 | ||
0793a61d | 2070 | /* |
cdd6c482 | 2071 | * Cross CPU call to install and enable a performance event |
682076ae PZ |
2072 | * |
2073 | * Must be called with ctx->mutex held | |
0793a61d | 2074 | */ |
fe4b04fa | 2075 | static int __perf_install_in_context(void *info) |
0793a61d | 2076 | { |
cdd6c482 IM |
2077 | struct perf_event *event = info; |
2078 | struct perf_event_context *ctx = event->ctx; | |
108b02cf | 2079 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
2c29ef0f PZ |
2080 | struct perf_event_context *task_ctx = cpuctx->task_ctx; |
2081 | struct task_struct *task = current; | |
2082 | ||
b58f6b0d | 2083 | perf_ctx_lock(cpuctx, task_ctx); |
2c29ef0f | 2084 | perf_pmu_disable(cpuctx->ctx.pmu); |
0793a61d TG |
2085 | |
2086 | /* | |
2c29ef0f | 2087 | * If there was an active task_ctx schedule it out. |
0793a61d | 2088 | */ |
b58f6b0d | 2089 | if (task_ctx) |
2c29ef0f | 2090 | task_ctx_sched_out(task_ctx); |
b58f6b0d PZ |
2091 | |
2092 | /* | |
2093 | * If the context we're installing events in is not the | |
2094 | * active task_ctx, flip them. | |
2095 | */ | |
2096 | if (ctx->task && task_ctx != ctx) { | |
2097 | if (task_ctx) | |
2098 | raw_spin_unlock(&task_ctx->lock); | |
2099 | raw_spin_lock(&ctx->lock); | |
2100 | task_ctx = ctx; | |
2101 | } | |
2102 | ||
2103 | if (task_ctx) { | |
2104 | cpuctx->task_ctx = task_ctx; | |
2c29ef0f PZ |
2105 | task = task_ctx->task; |
2106 | } | |
b58f6b0d | 2107 | |
2c29ef0f | 2108 | cpu_ctx_sched_out(cpuctx, EVENT_ALL); |
0793a61d | 2109 | |
4af4998b | 2110 | update_context_time(ctx); |
e5d1367f SE |
2111 | /* |
2112 | * update cgrp time only if current cgrp | |
2113 | * matches event->cgrp. Must be done before | |
2114 | * calling add_event_to_ctx() | |
2115 | */ | |
2116 | update_cgrp_time_from_event(event); | |
0793a61d | 2117 | |
cdd6c482 | 2118 | add_event_to_ctx(event, ctx); |
0793a61d | 2119 | |
d859e29f | 2120 | /* |
2c29ef0f | 2121 | * Schedule everything back in |
d859e29f | 2122 | */ |
dce5855b | 2123 | perf_event_sched_in(cpuctx, task_ctx, task); |
2c29ef0f PZ |
2124 | |
2125 | perf_pmu_enable(cpuctx->ctx.pmu); | |
2126 | perf_ctx_unlock(cpuctx, task_ctx); | |
fe4b04fa PZ |
2127 | |
2128 | return 0; | |
0793a61d TG |
2129 | } |
2130 | ||
2131 | /* | |
cdd6c482 | 2132 | * Attach a performance event to a context |
0793a61d TG |
2133 | */ |
2134 | static void | |
cdd6c482 IM |
2135 | perf_install_in_context(struct perf_event_context *ctx, |
2136 | struct perf_event *event, | |
0793a61d TG |
2137 | int cpu) |
2138 | { | |
fe4b04fa PZ |
2139 | lockdep_assert_held(&ctx->mutex); |
2140 | ||
c3f00c70 | 2141 | event->ctx = ctx; |
0cda4c02 YZ |
2142 | if (event->cpu != -1) |
2143 | event->cpu = cpu; | |
c3f00c70 | 2144 | |
0017960f PZ |
2145 | event_function_call(event, __perf_install_in_context, |
2146 | ___perf_install_in_context, event); | |
0793a61d TG |
2147 | } |
2148 | ||
fa289bec | 2149 | /* |
cdd6c482 | 2150 | * Put a event into inactive state and update time fields. |
fa289bec PM |
2151 | * Enabling the leader of a group effectively enables all |
2152 | * the group members that aren't explicitly disabled, so we | |
2153 | * have to update their ->tstamp_enabled also. | |
2154 | * Note: this works for group members as well as group leaders | |
2155 | * since the non-leader members' sibling_lists will be empty. | |
2156 | */ | |
1d9b482e | 2157 | static void __perf_event_mark_enabled(struct perf_event *event) |
fa289bec | 2158 | { |
cdd6c482 | 2159 | struct perf_event *sub; |
4158755d | 2160 | u64 tstamp = perf_event_time(event); |
fa289bec | 2161 | |
cdd6c482 | 2162 | event->state = PERF_EVENT_STATE_INACTIVE; |
4158755d | 2163 | event->tstamp_enabled = tstamp - event->total_time_enabled; |
9ed6060d | 2164 | list_for_each_entry(sub, &event->sibling_list, group_entry) { |
4158755d SE |
2165 | if (sub->state >= PERF_EVENT_STATE_INACTIVE) |
2166 | sub->tstamp_enabled = tstamp - sub->total_time_enabled; | |
9ed6060d | 2167 | } |
fa289bec PM |
2168 | } |
2169 | ||
d859e29f | 2170 | /* |
cdd6c482 | 2171 | * Cross CPU call to enable a performance event |
d859e29f | 2172 | */ |
fe4b04fa | 2173 | static int __perf_event_enable(void *info) |
04289bb9 | 2174 | { |
cdd6c482 | 2175 | struct perf_event *event = info; |
cdd6c482 IM |
2176 | struct perf_event_context *ctx = event->ctx; |
2177 | struct perf_event *leader = event->group_leader; | |
108b02cf | 2178 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
d859e29f | 2179 | int err; |
04289bb9 | 2180 | |
06f41796 JO |
2181 | /* |
2182 | * There's a time window between 'ctx->is_active' check | |
2183 | * in perf_event_enable function and this place having: | |
2184 | * - IRQs on | |
2185 | * - ctx->lock unlocked | |
2186 | * | |
2187 | * where the task could be killed and 'ctx' deactivated | |
2188 | * by perf_event_exit_task. | |
2189 | */ | |
2190 | if (!ctx->is_active) | |
fe4b04fa | 2191 | return -EINVAL; |
3cbed429 | 2192 | |
e625cce1 | 2193 | raw_spin_lock(&ctx->lock); |
4af4998b | 2194 | update_context_time(ctx); |
d859e29f | 2195 | |
cdd6c482 | 2196 | if (event->state >= PERF_EVENT_STATE_INACTIVE) |
d859e29f | 2197 | goto unlock; |
e5d1367f SE |
2198 | |
2199 | /* | |
2200 | * set current task's cgroup time reference point | |
2201 | */ | |
3f7cce3c | 2202 | perf_cgroup_set_timestamp(current, ctx); |
e5d1367f | 2203 | |
1d9b482e | 2204 | __perf_event_mark_enabled(event); |
04289bb9 | 2205 | |
e5d1367f SE |
2206 | if (!event_filter_match(event)) { |
2207 | if (is_cgroup_event(event)) | |
2208 | perf_cgroup_defer_enabled(event); | |
f4c4176f | 2209 | goto unlock; |
e5d1367f | 2210 | } |
f4c4176f | 2211 | |
04289bb9 | 2212 | /* |
cdd6c482 | 2213 | * If the event is in a group and isn't the group leader, |
d859e29f | 2214 | * then don't put it on unless the group is on. |
04289bb9 | 2215 | */ |
cdd6c482 | 2216 | if (leader != event && leader->state != PERF_EVENT_STATE_ACTIVE) |
d859e29f | 2217 | goto unlock; |
3b6f9e5c | 2218 | |
cdd6c482 | 2219 | if (!group_can_go_on(event, cpuctx, 1)) { |
d859e29f | 2220 | err = -EEXIST; |
e758a33d | 2221 | } else { |
cdd6c482 | 2222 | if (event == leader) |
6e37738a | 2223 | err = group_sched_in(event, cpuctx, ctx); |
e758a33d | 2224 | else |
6e37738a | 2225 | err = event_sched_in(event, cpuctx, ctx); |
e758a33d | 2226 | } |
d859e29f PM |
2227 | |
2228 | if (err) { | |
2229 | /* | |
cdd6c482 | 2230 | * If this event can't go on and it's part of a |
d859e29f PM |
2231 | * group, then the whole group has to come off. |
2232 | */ | |
9e630205 | 2233 | if (leader != event) { |
d859e29f | 2234 | group_sched_out(leader, cpuctx, ctx); |
272325c4 | 2235 | perf_mux_hrtimer_restart(cpuctx); |
9e630205 | 2236 | } |
0d48696f | 2237 | if (leader->attr.pinned) { |
53cfbf59 | 2238 | update_group_times(leader); |
cdd6c482 | 2239 | leader->state = PERF_EVENT_STATE_ERROR; |
53cfbf59 | 2240 | } |
d859e29f PM |
2241 | } |
2242 | ||
9ed6060d | 2243 | unlock: |
e625cce1 | 2244 | raw_spin_unlock(&ctx->lock); |
fe4b04fa PZ |
2245 | |
2246 | return 0; | |
d859e29f PM |
2247 | } |
2248 | ||
7b648018 PZ |
2249 | void ___perf_event_enable(void *info) |
2250 | { | |
2251 | __perf_event_mark_enabled((struct perf_event *)info); | |
2252 | } | |
2253 | ||
d859e29f | 2254 | /* |
cdd6c482 | 2255 | * Enable a event. |
c93f7669 | 2256 | * |
cdd6c482 IM |
2257 | * If event->ctx is a cloned context, callers must make sure that |
2258 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 2259 | * remains valid. This condition is satisfied when called through |
cdd6c482 IM |
2260 | * perf_event_for_each_child or perf_event_for_each as described |
2261 | * for perf_event_disable. | |
d859e29f | 2262 | */ |
f63a8daa | 2263 | static void _perf_event_enable(struct perf_event *event) |
d859e29f | 2264 | { |
cdd6c482 | 2265 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 2266 | |
7b648018 PZ |
2267 | raw_spin_lock_irq(&ctx->lock); |
2268 | if (event->state >= PERF_EVENT_STATE_INACTIVE) { | |
2269 | raw_spin_unlock_irq(&ctx->lock); | |
d859e29f PM |
2270 | return; |
2271 | } | |
2272 | ||
d859e29f | 2273 | /* |
cdd6c482 | 2274 | * If the event is in error state, clear that first. |
7b648018 PZ |
2275 | * |
2276 | * That way, if we see the event in error state below, we know that it | |
2277 | * has gone back into error state, as distinct from the task having | |
2278 | * been scheduled away before the cross-call arrived. | |
d859e29f | 2279 | */ |
cdd6c482 IM |
2280 | if (event->state == PERF_EVENT_STATE_ERROR) |
2281 | event->state = PERF_EVENT_STATE_OFF; | |
e625cce1 | 2282 | raw_spin_unlock_irq(&ctx->lock); |
fe4b04fa | 2283 | |
7b648018 PZ |
2284 | event_function_call(event, __perf_event_enable, |
2285 | ___perf_event_enable, event); | |
d859e29f | 2286 | } |
f63a8daa PZ |
2287 | |
2288 | /* | |
2289 | * See perf_event_disable(); | |
2290 | */ | |
2291 | void perf_event_enable(struct perf_event *event) | |
2292 | { | |
2293 | struct perf_event_context *ctx; | |
2294 | ||
2295 | ctx = perf_event_ctx_lock(event); | |
2296 | _perf_event_enable(event); | |
2297 | perf_event_ctx_unlock(event, ctx); | |
2298 | } | |
dcfce4a0 | 2299 | EXPORT_SYMBOL_GPL(perf_event_enable); |
d859e29f | 2300 | |
f63a8daa | 2301 | static int _perf_event_refresh(struct perf_event *event, int refresh) |
79f14641 | 2302 | { |
2023b359 | 2303 | /* |
cdd6c482 | 2304 | * not supported on inherited events |
2023b359 | 2305 | */ |
2e939d1d | 2306 | if (event->attr.inherit || !is_sampling_event(event)) |
2023b359 PZ |
2307 | return -EINVAL; |
2308 | ||
cdd6c482 | 2309 | atomic_add(refresh, &event->event_limit); |
f63a8daa | 2310 | _perf_event_enable(event); |
2023b359 PZ |
2311 | |
2312 | return 0; | |
79f14641 | 2313 | } |
f63a8daa PZ |
2314 | |
2315 | /* | |
2316 | * See perf_event_disable() | |
2317 | */ | |
2318 | int perf_event_refresh(struct perf_event *event, int refresh) | |
2319 | { | |
2320 | struct perf_event_context *ctx; | |
2321 | int ret; | |
2322 | ||
2323 | ctx = perf_event_ctx_lock(event); | |
2324 | ret = _perf_event_refresh(event, refresh); | |
2325 | perf_event_ctx_unlock(event, ctx); | |
2326 | ||
2327 | return ret; | |
2328 | } | |
26ca5c11 | 2329 | EXPORT_SYMBOL_GPL(perf_event_refresh); |
79f14641 | 2330 | |
5b0311e1 FW |
2331 | static void ctx_sched_out(struct perf_event_context *ctx, |
2332 | struct perf_cpu_context *cpuctx, | |
2333 | enum event_type_t event_type) | |
235c7fc7 | 2334 | { |
db24d33e | 2335 | int is_active = ctx->is_active; |
c994d613 PZ |
2336 | struct perf_event *event; |
2337 | ||
2338 | lockdep_assert_held(&ctx->lock); | |
235c7fc7 | 2339 | |
db24d33e | 2340 | ctx->is_active &= ~event_type; |
cdd6c482 | 2341 | if (likely(!ctx->nr_events)) |
facc4307 PZ |
2342 | return; |
2343 | ||
4af4998b | 2344 | update_context_time(ctx); |
e5d1367f | 2345 | update_cgrp_time_from_cpuctx(cpuctx); |
5b0311e1 | 2346 | if (!ctx->nr_active) |
facc4307 | 2347 | return; |
5b0311e1 | 2348 | |
075e0b00 | 2349 | perf_pmu_disable(ctx->pmu); |
db24d33e | 2350 | if ((is_active & EVENT_PINNED) && (event_type & EVENT_PINNED)) { |
889ff015 FW |
2351 | list_for_each_entry(event, &ctx->pinned_groups, group_entry) |
2352 | group_sched_out(event, cpuctx, ctx); | |
9ed6060d | 2353 | } |
889ff015 | 2354 | |
db24d33e | 2355 | if ((is_active & EVENT_FLEXIBLE) && (event_type & EVENT_FLEXIBLE)) { |
889ff015 | 2356 | list_for_each_entry(event, &ctx->flexible_groups, group_entry) |
8c9ed8e1 | 2357 | group_sched_out(event, cpuctx, ctx); |
9ed6060d | 2358 | } |
1b9a644f | 2359 | perf_pmu_enable(ctx->pmu); |
235c7fc7 IM |
2360 | } |
2361 | ||
564c2b21 | 2362 | /* |
5a3126d4 PZ |
2363 | * Test whether two contexts are equivalent, i.e. whether they have both been |
2364 | * cloned from the same version of the same context. | |
2365 | * | |
2366 | * Equivalence is measured using a generation number in the context that is | |
2367 | * incremented on each modification to it; see unclone_ctx(), list_add_event() | |
2368 | * and list_del_event(). | |
564c2b21 | 2369 | */ |
cdd6c482 IM |
2370 | static int context_equiv(struct perf_event_context *ctx1, |
2371 | struct perf_event_context *ctx2) | |
564c2b21 | 2372 | { |
211de6eb PZ |
2373 | lockdep_assert_held(&ctx1->lock); |
2374 | lockdep_assert_held(&ctx2->lock); | |
2375 | ||
5a3126d4 PZ |
2376 | /* Pinning disables the swap optimization */ |
2377 | if (ctx1->pin_count || ctx2->pin_count) | |
2378 | return 0; | |
2379 | ||
2380 | /* If ctx1 is the parent of ctx2 */ | |
2381 | if (ctx1 == ctx2->parent_ctx && ctx1->generation == ctx2->parent_gen) | |
2382 | return 1; | |
2383 | ||
2384 | /* If ctx2 is the parent of ctx1 */ | |
2385 | if (ctx1->parent_ctx == ctx2 && ctx1->parent_gen == ctx2->generation) | |
2386 | return 1; | |
2387 | ||
2388 | /* | |
2389 | * If ctx1 and ctx2 have the same parent; we flatten the parent | |
2390 | * hierarchy, see perf_event_init_context(). | |
2391 | */ | |
2392 | if (ctx1->parent_ctx && ctx1->parent_ctx == ctx2->parent_ctx && | |
2393 | ctx1->parent_gen == ctx2->parent_gen) | |
2394 | return 1; | |
2395 | ||
2396 | /* Unmatched */ | |
2397 | return 0; | |
564c2b21 PM |
2398 | } |
2399 | ||
cdd6c482 IM |
2400 | static void __perf_event_sync_stat(struct perf_event *event, |
2401 | struct perf_event *next_event) | |
bfbd3381 PZ |
2402 | { |
2403 | u64 value; | |
2404 | ||
cdd6c482 | 2405 | if (!event->attr.inherit_stat) |
bfbd3381 PZ |
2406 | return; |
2407 | ||
2408 | /* | |
cdd6c482 | 2409 | * Update the event value, we cannot use perf_event_read() |
bfbd3381 PZ |
2410 | * because we're in the middle of a context switch and have IRQs |
2411 | * disabled, which upsets smp_call_function_single(), however | |
cdd6c482 | 2412 | * we know the event must be on the current CPU, therefore we |
bfbd3381 PZ |
2413 | * don't need to use it. |
2414 | */ | |
cdd6c482 IM |
2415 | switch (event->state) { |
2416 | case PERF_EVENT_STATE_ACTIVE: | |
3dbebf15 PZ |
2417 | event->pmu->read(event); |
2418 | /* fall-through */ | |
bfbd3381 | 2419 | |
cdd6c482 IM |
2420 | case PERF_EVENT_STATE_INACTIVE: |
2421 | update_event_times(event); | |
bfbd3381 PZ |
2422 | break; |
2423 | ||
2424 | default: | |
2425 | break; | |
2426 | } | |
2427 | ||
2428 | /* | |
cdd6c482 | 2429 | * In order to keep per-task stats reliable we need to flip the event |
bfbd3381 PZ |
2430 | * values when we flip the contexts. |
2431 | */ | |
e7850595 PZ |
2432 | value = local64_read(&next_event->count); |
2433 | value = local64_xchg(&event->count, value); | |
2434 | local64_set(&next_event->count, value); | |
bfbd3381 | 2435 | |
cdd6c482 IM |
2436 | swap(event->total_time_enabled, next_event->total_time_enabled); |
2437 | swap(event->total_time_running, next_event->total_time_running); | |
19d2e755 | 2438 | |
bfbd3381 | 2439 | /* |
19d2e755 | 2440 | * Since we swizzled the values, update the user visible data too. |
bfbd3381 | 2441 | */ |
cdd6c482 IM |
2442 | perf_event_update_userpage(event); |
2443 | perf_event_update_userpage(next_event); | |
bfbd3381 PZ |
2444 | } |
2445 | ||
cdd6c482 IM |
2446 | static void perf_event_sync_stat(struct perf_event_context *ctx, |
2447 | struct perf_event_context *next_ctx) | |
bfbd3381 | 2448 | { |
cdd6c482 | 2449 | struct perf_event *event, *next_event; |
bfbd3381 PZ |
2450 | |
2451 | if (!ctx->nr_stat) | |
2452 | return; | |
2453 | ||
02ffdbc8 PZ |
2454 | update_context_time(ctx); |
2455 | ||
cdd6c482 IM |
2456 | event = list_first_entry(&ctx->event_list, |
2457 | struct perf_event, event_entry); | |
bfbd3381 | 2458 | |
cdd6c482 IM |
2459 | next_event = list_first_entry(&next_ctx->event_list, |
2460 | struct perf_event, event_entry); | |
bfbd3381 | 2461 | |
cdd6c482 IM |
2462 | while (&event->event_entry != &ctx->event_list && |
2463 | &next_event->event_entry != &next_ctx->event_list) { | |
bfbd3381 | 2464 | |
cdd6c482 | 2465 | __perf_event_sync_stat(event, next_event); |
bfbd3381 | 2466 | |
cdd6c482 IM |
2467 | event = list_next_entry(event, event_entry); |
2468 | next_event = list_next_entry(next_event, event_entry); | |
bfbd3381 PZ |
2469 | } |
2470 | } | |
2471 | ||
fe4b04fa PZ |
2472 | static void perf_event_context_sched_out(struct task_struct *task, int ctxn, |
2473 | struct task_struct *next) | |
0793a61d | 2474 | { |
8dc85d54 | 2475 | struct perf_event_context *ctx = task->perf_event_ctxp[ctxn]; |
cdd6c482 | 2476 | struct perf_event_context *next_ctx; |
5a3126d4 | 2477 | struct perf_event_context *parent, *next_parent; |
108b02cf | 2478 | struct perf_cpu_context *cpuctx; |
c93f7669 | 2479 | int do_switch = 1; |
0793a61d | 2480 | |
108b02cf PZ |
2481 | if (likely(!ctx)) |
2482 | return; | |
10989fb2 | 2483 | |
108b02cf PZ |
2484 | cpuctx = __get_cpu_context(ctx); |
2485 | if (!cpuctx->task_ctx) | |
0793a61d TG |
2486 | return; |
2487 | ||
c93f7669 | 2488 | rcu_read_lock(); |
8dc85d54 | 2489 | next_ctx = next->perf_event_ctxp[ctxn]; |
5a3126d4 PZ |
2490 | if (!next_ctx) |
2491 | goto unlock; | |
2492 | ||
2493 | parent = rcu_dereference(ctx->parent_ctx); | |
2494 | next_parent = rcu_dereference(next_ctx->parent_ctx); | |
2495 | ||
2496 | /* If neither context have a parent context; they cannot be clones. */ | |
802c8a61 | 2497 | if (!parent && !next_parent) |
5a3126d4 PZ |
2498 | goto unlock; |
2499 | ||
2500 | if (next_parent == ctx || next_ctx == parent || next_parent == parent) { | |
c93f7669 PM |
2501 | /* |
2502 | * Looks like the two contexts are clones, so we might be | |
2503 | * able to optimize the context switch. We lock both | |
2504 | * contexts and check that they are clones under the | |
2505 | * lock (including re-checking that neither has been | |
2506 | * uncloned in the meantime). It doesn't matter which | |
2507 | * order we take the locks because no other cpu could | |
2508 | * be trying to lock both of these tasks. | |
2509 | */ | |
e625cce1 TG |
2510 | raw_spin_lock(&ctx->lock); |
2511 | raw_spin_lock_nested(&next_ctx->lock, SINGLE_DEPTH_NESTING); | |
c93f7669 | 2512 | if (context_equiv(ctx, next_ctx)) { |
665c2142 PZ |
2513 | /* |
2514 | * XXX do we need a memory barrier of sorts | |
cdd6c482 | 2515 | * wrt to rcu_dereference() of perf_event_ctxp |
665c2142 | 2516 | */ |
8dc85d54 PZ |
2517 | task->perf_event_ctxp[ctxn] = next_ctx; |
2518 | next->perf_event_ctxp[ctxn] = ctx; | |
c93f7669 PM |
2519 | ctx->task = next; |
2520 | next_ctx->task = task; | |
5a158c3c YZ |
2521 | |
2522 | swap(ctx->task_ctx_data, next_ctx->task_ctx_data); | |
2523 | ||
c93f7669 | 2524 | do_switch = 0; |
bfbd3381 | 2525 | |
cdd6c482 | 2526 | perf_event_sync_stat(ctx, next_ctx); |
c93f7669 | 2527 | } |
e625cce1 TG |
2528 | raw_spin_unlock(&next_ctx->lock); |
2529 | raw_spin_unlock(&ctx->lock); | |
564c2b21 | 2530 | } |
5a3126d4 | 2531 | unlock: |
c93f7669 | 2532 | rcu_read_unlock(); |
564c2b21 | 2533 | |
c93f7669 | 2534 | if (do_switch) { |
facc4307 | 2535 | raw_spin_lock(&ctx->lock); |
5b0311e1 | 2536 | ctx_sched_out(ctx, cpuctx, EVENT_ALL); |
c93f7669 | 2537 | cpuctx->task_ctx = NULL; |
facc4307 | 2538 | raw_spin_unlock(&ctx->lock); |
c93f7669 | 2539 | } |
0793a61d TG |
2540 | } |
2541 | ||
ba532500 YZ |
2542 | void perf_sched_cb_dec(struct pmu *pmu) |
2543 | { | |
2544 | this_cpu_dec(perf_sched_cb_usages); | |
2545 | } | |
2546 | ||
2547 | void perf_sched_cb_inc(struct pmu *pmu) | |
2548 | { | |
2549 | this_cpu_inc(perf_sched_cb_usages); | |
2550 | } | |
2551 | ||
2552 | /* | |
2553 | * This function provides the context switch callback to the lower code | |
2554 | * layer. It is invoked ONLY when the context switch callback is enabled. | |
2555 | */ | |
2556 | static void perf_pmu_sched_task(struct task_struct *prev, | |
2557 | struct task_struct *next, | |
2558 | bool sched_in) | |
2559 | { | |
2560 | struct perf_cpu_context *cpuctx; | |
2561 | struct pmu *pmu; | |
2562 | unsigned long flags; | |
2563 | ||
2564 | if (prev == next) | |
2565 | return; | |
2566 | ||
2567 | local_irq_save(flags); | |
2568 | ||
2569 | rcu_read_lock(); | |
2570 | ||
2571 | list_for_each_entry_rcu(pmu, &pmus, entry) { | |
2572 | if (pmu->sched_task) { | |
2573 | cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); | |
2574 | ||
2575 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); | |
2576 | ||
2577 | perf_pmu_disable(pmu); | |
2578 | ||
2579 | pmu->sched_task(cpuctx->task_ctx, sched_in); | |
2580 | ||
2581 | perf_pmu_enable(pmu); | |
2582 | ||
2583 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
2584 | } | |
2585 | } | |
2586 | ||
2587 | rcu_read_unlock(); | |
2588 | ||
2589 | local_irq_restore(flags); | |
2590 | } | |
2591 | ||
45ac1403 AH |
2592 | static void perf_event_switch(struct task_struct *task, |
2593 | struct task_struct *next_prev, bool sched_in); | |
2594 | ||
8dc85d54 PZ |
2595 | #define for_each_task_context_nr(ctxn) \ |
2596 | for ((ctxn) = 0; (ctxn) < perf_nr_task_contexts; (ctxn)++) | |
2597 | ||
2598 | /* | |
2599 | * Called from scheduler to remove the events of the current task, | |
2600 | * with interrupts disabled. | |
2601 | * | |
2602 | * We stop each event and update the event value in event->count. | |
2603 | * | |
2604 | * This does not protect us against NMI, but disable() | |
2605 | * sets the disabled bit in the control field of event _before_ | |
2606 | * accessing the event control register. If a NMI hits, then it will | |
2607 | * not restart the event. | |
2608 | */ | |
ab0cce56 JO |
2609 | void __perf_event_task_sched_out(struct task_struct *task, |
2610 | struct task_struct *next) | |
8dc85d54 PZ |
2611 | { |
2612 | int ctxn; | |
2613 | ||
ba532500 YZ |
2614 | if (__this_cpu_read(perf_sched_cb_usages)) |
2615 | perf_pmu_sched_task(task, next, false); | |
2616 | ||
45ac1403 AH |
2617 | if (atomic_read(&nr_switch_events)) |
2618 | perf_event_switch(task, next, false); | |
2619 | ||
8dc85d54 PZ |
2620 | for_each_task_context_nr(ctxn) |
2621 | perf_event_context_sched_out(task, ctxn, next); | |
e5d1367f SE |
2622 | |
2623 | /* | |
2624 | * if cgroup events exist on this CPU, then we need | |
2625 | * to check if we have to switch out PMU state. | |
2626 | * cgroup event are system-wide mode only | |
2627 | */ | |
4a32fea9 | 2628 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) |
a8d757ef | 2629 | perf_cgroup_sched_out(task, next); |
8dc85d54 PZ |
2630 | } |
2631 | ||
04dc2dbb | 2632 | static void task_ctx_sched_out(struct perf_event_context *ctx) |
a08b159f | 2633 | { |
108b02cf | 2634 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
a08b159f | 2635 | |
a63eaf34 PM |
2636 | if (!cpuctx->task_ctx) |
2637 | return; | |
012b84da IM |
2638 | |
2639 | if (WARN_ON_ONCE(ctx != cpuctx->task_ctx)) | |
2640 | return; | |
2641 | ||
04dc2dbb | 2642 | ctx_sched_out(ctx, cpuctx, EVENT_ALL); |
a08b159f PM |
2643 | cpuctx->task_ctx = NULL; |
2644 | } | |
2645 | ||
5b0311e1 FW |
2646 | /* |
2647 | * Called with IRQs disabled | |
2648 | */ | |
2649 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, | |
2650 | enum event_type_t event_type) | |
2651 | { | |
2652 | ctx_sched_out(&cpuctx->ctx, cpuctx, event_type); | |
04289bb9 IM |
2653 | } |
2654 | ||
235c7fc7 | 2655 | static void |
5b0311e1 | 2656 | ctx_pinned_sched_in(struct perf_event_context *ctx, |
6e37738a | 2657 | struct perf_cpu_context *cpuctx) |
0793a61d | 2658 | { |
cdd6c482 | 2659 | struct perf_event *event; |
0793a61d | 2660 | |
889ff015 FW |
2661 | list_for_each_entry(event, &ctx->pinned_groups, group_entry) { |
2662 | if (event->state <= PERF_EVENT_STATE_OFF) | |
3b6f9e5c | 2663 | continue; |
5632ab12 | 2664 | if (!event_filter_match(event)) |
3b6f9e5c PM |
2665 | continue; |
2666 | ||
e5d1367f SE |
2667 | /* may need to reset tstamp_enabled */ |
2668 | if (is_cgroup_event(event)) | |
2669 | perf_cgroup_mark_enabled(event, ctx); | |
2670 | ||
8c9ed8e1 | 2671 | if (group_can_go_on(event, cpuctx, 1)) |
6e37738a | 2672 | group_sched_in(event, cpuctx, ctx); |
3b6f9e5c PM |
2673 | |
2674 | /* | |
2675 | * If this pinned group hasn't been scheduled, | |
2676 | * put it in error state. | |
2677 | */ | |
cdd6c482 IM |
2678 | if (event->state == PERF_EVENT_STATE_INACTIVE) { |
2679 | update_group_times(event); | |
2680 | event->state = PERF_EVENT_STATE_ERROR; | |
53cfbf59 | 2681 | } |
3b6f9e5c | 2682 | } |
5b0311e1 FW |
2683 | } |
2684 | ||
2685 | static void | |
2686 | ctx_flexible_sched_in(struct perf_event_context *ctx, | |
6e37738a | 2687 | struct perf_cpu_context *cpuctx) |
5b0311e1 FW |
2688 | { |
2689 | struct perf_event *event; | |
2690 | int can_add_hw = 1; | |
3b6f9e5c | 2691 | |
889ff015 FW |
2692 | list_for_each_entry(event, &ctx->flexible_groups, group_entry) { |
2693 | /* Ignore events in OFF or ERROR state */ | |
2694 | if (event->state <= PERF_EVENT_STATE_OFF) | |
3b6f9e5c | 2695 | continue; |
04289bb9 IM |
2696 | /* |
2697 | * Listen to the 'cpu' scheduling filter constraint | |
cdd6c482 | 2698 | * of events: |
04289bb9 | 2699 | */ |
5632ab12 | 2700 | if (!event_filter_match(event)) |
0793a61d TG |
2701 | continue; |
2702 | ||
e5d1367f SE |
2703 | /* may need to reset tstamp_enabled */ |
2704 | if (is_cgroup_event(event)) | |
2705 | perf_cgroup_mark_enabled(event, ctx); | |
2706 | ||
9ed6060d | 2707 | if (group_can_go_on(event, cpuctx, can_add_hw)) { |
6e37738a | 2708 | if (group_sched_in(event, cpuctx, ctx)) |
dd0e6ba2 | 2709 | can_add_hw = 0; |
9ed6060d | 2710 | } |
0793a61d | 2711 | } |
5b0311e1 FW |
2712 | } |
2713 | ||
2714 | static void | |
2715 | ctx_sched_in(struct perf_event_context *ctx, | |
2716 | struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
2717 | enum event_type_t event_type, |
2718 | struct task_struct *task) | |
5b0311e1 | 2719 | { |
db24d33e | 2720 | int is_active = ctx->is_active; |
c994d613 PZ |
2721 | u64 now; |
2722 | ||
2723 | lockdep_assert_held(&ctx->lock); | |
e5d1367f | 2724 | |
db24d33e | 2725 | ctx->is_active |= event_type; |
5b0311e1 | 2726 | if (likely(!ctx->nr_events)) |
facc4307 | 2727 | return; |
5b0311e1 | 2728 | |
e5d1367f SE |
2729 | now = perf_clock(); |
2730 | ctx->timestamp = now; | |
3f7cce3c | 2731 | perf_cgroup_set_timestamp(task, ctx); |
5b0311e1 FW |
2732 | /* |
2733 | * First go through the list and put on any pinned groups | |
2734 | * in order to give them the best chance of going on. | |
2735 | */ | |
db24d33e | 2736 | if (!(is_active & EVENT_PINNED) && (event_type & EVENT_PINNED)) |
6e37738a | 2737 | ctx_pinned_sched_in(ctx, cpuctx); |
5b0311e1 FW |
2738 | |
2739 | /* Then walk through the lower prio flexible groups */ | |
db24d33e | 2740 | if (!(is_active & EVENT_FLEXIBLE) && (event_type & EVENT_FLEXIBLE)) |
6e37738a | 2741 | ctx_flexible_sched_in(ctx, cpuctx); |
235c7fc7 IM |
2742 | } |
2743 | ||
329c0e01 | 2744 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, |
e5d1367f SE |
2745 | enum event_type_t event_type, |
2746 | struct task_struct *task) | |
329c0e01 FW |
2747 | { |
2748 | struct perf_event_context *ctx = &cpuctx->ctx; | |
2749 | ||
e5d1367f | 2750 | ctx_sched_in(ctx, cpuctx, event_type, task); |
329c0e01 FW |
2751 | } |
2752 | ||
e5d1367f SE |
2753 | static void perf_event_context_sched_in(struct perf_event_context *ctx, |
2754 | struct task_struct *task) | |
235c7fc7 | 2755 | { |
108b02cf | 2756 | struct perf_cpu_context *cpuctx; |
235c7fc7 | 2757 | |
108b02cf | 2758 | cpuctx = __get_cpu_context(ctx); |
329c0e01 FW |
2759 | if (cpuctx->task_ctx == ctx) |
2760 | return; | |
2761 | ||
facc4307 | 2762 | perf_ctx_lock(cpuctx, ctx); |
1b9a644f | 2763 | perf_pmu_disable(ctx->pmu); |
329c0e01 FW |
2764 | /* |
2765 | * We want to keep the following priority order: | |
2766 | * cpu pinned (that don't need to move), task pinned, | |
2767 | * cpu flexible, task flexible. | |
2768 | */ | |
2769 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
2770 | ||
1d5f003f GN |
2771 | if (ctx->nr_events) |
2772 | cpuctx->task_ctx = ctx; | |
9b33fa6b | 2773 | |
86b47c25 GN |
2774 | perf_event_sched_in(cpuctx, cpuctx->task_ctx, task); |
2775 | ||
facc4307 PZ |
2776 | perf_pmu_enable(ctx->pmu); |
2777 | perf_ctx_unlock(cpuctx, ctx); | |
235c7fc7 IM |
2778 | } |
2779 | ||
8dc85d54 PZ |
2780 | /* |
2781 | * Called from scheduler to add the events of the current task | |
2782 | * with interrupts disabled. | |
2783 | * | |
2784 | * We restore the event value and then enable it. | |
2785 | * | |
2786 | * This does not protect us against NMI, but enable() | |
2787 | * sets the enabled bit in the control field of event _before_ | |
2788 | * accessing the event control register. If a NMI hits, then it will | |
2789 | * keep the event running. | |
2790 | */ | |
ab0cce56 JO |
2791 | void __perf_event_task_sched_in(struct task_struct *prev, |
2792 | struct task_struct *task) | |
8dc85d54 PZ |
2793 | { |
2794 | struct perf_event_context *ctx; | |
2795 | int ctxn; | |
2796 | ||
7e41d177 PZ |
2797 | /* |
2798 | * If cgroup events exist on this CPU, then we need to check if we have | |
2799 | * to switch in PMU state; cgroup event are system-wide mode only. | |
2800 | * | |
2801 | * Since cgroup events are CPU events, we must schedule these in before | |
2802 | * we schedule in the task events. | |
2803 | */ | |
2804 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) | |
2805 | perf_cgroup_sched_in(prev, task); | |
2806 | ||
8dc85d54 PZ |
2807 | for_each_task_context_nr(ctxn) { |
2808 | ctx = task->perf_event_ctxp[ctxn]; | |
2809 | if (likely(!ctx)) | |
2810 | continue; | |
2811 | ||
e5d1367f | 2812 | perf_event_context_sched_in(ctx, task); |
8dc85d54 | 2813 | } |
d010b332 | 2814 | |
45ac1403 AH |
2815 | if (atomic_read(&nr_switch_events)) |
2816 | perf_event_switch(task, prev, true); | |
2817 | ||
ba532500 YZ |
2818 | if (__this_cpu_read(perf_sched_cb_usages)) |
2819 | perf_pmu_sched_task(prev, task, true); | |
235c7fc7 IM |
2820 | } |
2821 | ||
abd50713 PZ |
2822 | static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count) |
2823 | { | |
2824 | u64 frequency = event->attr.sample_freq; | |
2825 | u64 sec = NSEC_PER_SEC; | |
2826 | u64 divisor, dividend; | |
2827 | ||
2828 | int count_fls, nsec_fls, frequency_fls, sec_fls; | |
2829 | ||
2830 | count_fls = fls64(count); | |
2831 | nsec_fls = fls64(nsec); | |
2832 | frequency_fls = fls64(frequency); | |
2833 | sec_fls = 30; | |
2834 | ||
2835 | /* | |
2836 | * We got @count in @nsec, with a target of sample_freq HZ | |
2837 | * the target period becomes: | |
2838 | * | |
2839 | * @count * 10^9 | |
2840 | * period = ------------------- | |
2841 | * @nsec * sample_freq | |
2842 | * | |
2843 | */ | |
2844 | ||
2845 | /* | |
2846 | * Reduce accuracy by one bit such that @a and @b converge | |
2847 | * to a similar magnitude. | |
2848 | */ | |
fe4b04fa | 2849 | #define REDUCE_FLS(a, b) \ |
abd50713 PZ |
2850 | do { \ |
2851 | if (a##_fls > b##_fls) { \ | |
2852 | a >>= 1; \ | |
2853 | a##_fls--; \ | |
2854 | } else { \ | |
2855 | b >>= 1; \ | |
2856 | b##_fls--; \ | |
2857 | } \ | |
2858 | } while (0) | |
2859 | ||
2860 | /* | |
2861 | * Reduce accuracy until either term fits in a u64, then proceed with | |
2862 | * the other, so that finally we can do a u64/u64 division. | |
2863 | */ | |
2864 | while (count_fls + sec_fls > 64 && nsec_fls + frequency_fls > 64) { | |
2865 | REDUCE_FLS(nsec, frequency); | |
2866 | REDUCE_FLS(sec, count); | |
2867 | } | |
2868 | ||
2869 | if (count_fls + sec_fls > 64) { | |
2870 | divisor = nsec * frequency; | |
2871 | ||
2872 | while (count_fls + sec_fls > 64) { | |
2873 | REDUCE_FLS(count, sec); | |
2874 | divisor >>= 1; | |
2875 | } | |
2876 | ||
2877 | dividend = count * sec; | |
2878 | } else { | |
2879 | dividend = count * sec; | |
2880 | ||
2881 | while (nsec_fls + frequency_fls > 64) { | |
2882 | REDUCE_FLS(nsec, frequency); | |
2883 | dividend >>= 1; | |
2884 | } | |
2885 | ||
2886 | divisor = nsec * frequency; | |
2887 | } | |
2888 | ||
f6ab91ad PZ |
2889 | if (!divisor) |
2890 | return dividend; | |
2891 | ||
abd50713 PZ |
2892 | return div64_u64(dividend, divisor); |
2893 | } | |
2894 | ||
e050e3f0 SE |
2895 | static DEFINE_PER_CPU(int, perf_throttled_count); |
2896 | static DEFINE_PER_CPU(u64, perf_throttled_seq); | |
2897 | ||
f39d47ff | 2898 | static void perf_adjust_period(struct perf_event *event, u64 nsec, u64 count, bool disable) |
bd2b5b12 | 2899 | { |
cdd6c482 | 2900 | struct hw_perf_event *hwc = &event->hw; |
f6ab91ad | 2901 | s64 period, sample_period; |
bd2b5b12 PZ |
2902 | s64 delta; |
2903 | ||
abd50713 | 2904 | period = perf_calculate_period(event, nsec, count); |
bd2b5b12 PZ |
2905 | |
2906 | delta = (s64)(period - hwc->sample_period); | |
2907 | delta = (delta + 7) / 8; /* low pass filter */ | |
2908 | ||
2909 | sample_period = hwc->sample_period + delta; | |
2910 | ||
2911 | if (!sample_period) | |
2912 | sample_period = 1; | |
2913 | ||
bd2b5b12 | 2914 | hwc->sample_period = sample_period; |
abd50713 | 2915 | |
e7850595 | 2916 | if (local64_read(&hwc->period_left) > 8*sample_period) { |
f39d47ff SE |
2917 | if (disable) |
2918 | event->pmu->stop(event, PERF_EF_UPDATE); | |
2919 | ||
e7850595 | 2920 | local64_set(&hwc->period_left, 0); |
f39d47ff SE |
2921 | |
2922 | if (disable) | |
2923 | event->pmu->start(event, PERF_EF_RELOAD); | |
abd50713 | 2924 | } |
bd2b5b12 PZ |
2925 | } |
2926 | ||
e050e3f0 SE |
2927 | /* |
2928 | * combine freq adjustment with unthrottling to avoid two passes over the | |
2929 | * events. At the same time, make sure, having freq events does not change | |
2930 | * the rate of unthrottling as that would introduce bias. | |
2931 | */ | |
2932 | static void perf_adjust_freq_unthr_context(struct perf_event_context *ctx, | |
2933 | int needs_unthr) | |
60db5e09 | 2934 | { |
cdd6c482 IM |
2935 | struct perf_event *event; |
2936 | struct hw_perf_event *hwc; | |
e050e3f0 | 2937 | u64 now, period = TICK_NSEC; |
abd50713 | 2938 | s64 delta; |
60db5e09 | 2939 | |
e050e3f0 SE |
2940 | /* |
2941 | * only need to iterate over all events iff: | |
2942 | * - context have events in frequency mode (needs freq adjust) | |
2943 | * - there are events to unthrottle on this cpu | |
2944 | */ | |
2945 | if (!(ctx->nr_freq || needs_unthr)) | |
0f5a2601 PZ |
2946 | return; |
2947 | ||
e050e3f0 | 2948 | raw_spin_lock(&ctx->lock); |
f39d47ff | 2949 | perf_pmu_disable(ctx->pmu); |
e050e3f0 | 2950 | |
03541f8b | 2951 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { |
cdd6c482 | 2952 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
60db5e09 PZ |
2953 | continue; |
2954 | ||
5632ab12 | 2955 | if (!event_filter_match(event)) |
5d27c23d PZ |
2956 | continue; |
2957 | ||
44377277 AS |
2958 | perf_pmu_disable(event->pmu); |
2959 | ||
cdd6c482 | 2960 | hwc = &event->hw; |
6a24ed6c | 2961 | |
ae23bff1 | 2962 | if (hwc->interrupts == MAX_INTERRUPTS) { |
e050e3f0 | 2963 | hwc->interrupts = 0; |
cdd6c482 | 2964 | perf_log_throttle(event, 1); |
a4eaf7f1 | 2965 | event->pmu->start(event, 0); |
a78ac325 PZ |
2966 | } |
2967 | ||
cdd6c482 | 2968 | if (!event->attr.freq || !event->attr.sample_freq) |
44377277 | 2969 | goto next; |
60db5e09 | 2970 | |
e050e3f0 SE |
2971 | /* |
2972 | * stop the event and update event->count | |
2973 | */ | |
2974 | event->pmu->stop(event, PERF_EF_UPDATE); | |
2975 | ||
e7850595 | 2976 | now = local64_read(&event->count); |
abd50713 PZ |
2977 | delta = now - hwc->freq_count_stamp; |
2978 | hwc->freq_count_stamp = now; | |
60db5e09 | 2979 | |
e050e3f0 SE |
2980 | /* |
2981 | * restart the event | |
2982 | * reload only if value has changed | |
f39d47ff SE |
2983 | * we have stopped the event so tell that |
2984 | * to perf_adjust_period() to avoid stopping it | |
2985 | * twice. | |
e050e3f0 | 2986 | */ |
abd50713 | 2987 | if (delta > 0) |
f39d47ff | 2988 | perf_adjust_period(event, period, delta, false); |
e050e3f0 SE |
2989 | |
2990 | event->pmu->start(event, delta > 0 ? PERF_EF_RELOAD : 0); | |
44377277 AS |
2991 | next: |
2992 | perf_pmu_enable(event->pmu); | |
60db5e09 | 2993 | } |
e050e3f0 | 2994 | |
f39d47ff | 2995 | perf_pmu_enable(ctx->pmu); |
e050e3f0 | 2996 | raw_spin_unlock(&ctx->lock); |
60db5e09 PZ |
2997 | } |
2998 | ||
235c7fc7 | 2999 | /* |
cdd6c482 | 3000 | * Round-robin a context's events: |
235c7fc7 | 3001 | */ |
cdd6c482 | 3002 | static void rotate_ctx(struct perf_event_context *ctx) |
0793a61d | 3003 | { |
dddd3379 TG |
3004 | /* |
3005 | * Rotate the first entry last of non-pinned groups. Rotation might be | |
3006 | * disabled by the inheritance code. | |
3007 | */ | |
3008 | if (!ctx->rotate_disable) | |
3009 | list_rotate_left(&ctx->flexible_groups); | |
235c7fc7 IM |
3010 | } |
3011 | ||
9e630205 | 3012 | static int perf_rotate_context(struct perf_cpu_context *cpuctx) |
235c7fc7 | 3013 | { |
8dc85d54 | 3014 | struct perf_event_context *ctx = NULL; |
2fde4f94 | 3015 | int rotate = 0; |
7fc23a53 | 3016 | |
b5ab4cd5 | 3017 | if (cpuctx->ctx.nr_events) { |
b5ab4cd5 PZ |
3018 | if (cpuctx->ctx.nr_events != cpuctx->ctx.nr_active) |
3019 | rotate = 1; | |
3020 | } | |
235c7fc7 | 3021 | |
8dc85d54 | 3022 | ctx = cpuctx->task_ctx; |
b5ab4cd5 | 3023 | if (ctx && ctx->nr_events) { |
b5ab4cd5 PZ |
3024 | if (ctx->nr_events != ctx->nr_active) |
3025 | rotate = 1; | |
3026 | } | |
9717e6cd | 3027 | |
e050e3f0 | 3028 | if (!rotate) |
0f5a2601 PZ |
3029 | goto done; |
3030 | ||
facc4307 | 3031 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
1b9a644f | 3032 | perf_pmu_disable(cpuctx->ctx.pmu); |
60db5e09 | 3033 | |
e050e3f0 SE |
3034 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); |
3035 | if (ctx) | |
3036 | ctx_sched_out(ctx, cpuctx, EVENT_FLEXIBLE); | |
0793a61d | 3037 | |
e050e3f0 SE |
3038 | rotate_ctx(&cpuctx->ctx); |
3039 | if (ctx) | |
3040 | rotate_ctx(ctx); | |
235c7fc7 | 3041 | |
e050e3f0 | 3042 | perf_event_sched_in(cpuctx, ctx, current); |
235c7fc7 | 3043 | |
0f5a2601 PZ |
3044 | perf_pmu_enable(cpuctx->ctx.pmu); |
3045 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
b5ab4cd5 | 3046 | done: |
9e630205 SE |
3047 | |
3048 | return rotate; | |
e9d2b064 PZ |
3049 | } |
3050 | ||
026249ef FW |
3051 | #ifdef CONFIG_NO_HZ_FULL |
3052 | bool perf_event_can_stop_tick(void) | |
3053 | { | |
948b26b6 | 3054 | if (atomic_read(&nr_freq_events) || |
d84153d6 | 3055 | __this_cpu_read(perf_throttled_count)) |
026249ef | 3056 | return false; |
d84153d6 FW |
3057 | else |
3058 | return true; | |
026249ef FW |
3059 | } |
3060 | #endif | |
3061 | ||
e9d2b064 PZ |
3062 | void perf_event_task_tick(void) |
3063 | { | |
2fde4f94 MR |
3064 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
3065 | struct perf_event_context *ctx, *tmp; | |
e050e3f0 | 3066 | int throttled; |
b5ab4cd5 | 3067 | |
e9d2b064 PZ |
3068 | WARN_ON(!irqs_disabled()); |
3069 | ||
e050e3f0 SE |
3070 | __this_cpu_inc(perf_throttled_seq); |
3071 | throttled = __this_cpu_xchg(perf_throttled_count, 0); | |
3072 | ||
2fde4f94 | 3073 | list_for_each_entry_safe(ctx, tmp, head, active_ctx_list) |
e050e3f0 | 3074 | perf_adjust_freq_unthr_context(ctx, throttled); |
0793a61d TG |
3075 | } |
3076 | ||
889ff015 FW |
3077 | static int event_enable_on_exec(struct perf_event *event, |
3078 | struct perf_event_context *ctx) | |
3079 | { | |
3080 | if (!event->attr.enable_on_exec) | |
3081 | return 0; | |
3082 | ||
3083 | event->attr.enable_on_exec = 0; | |
3084 | if (event->state >= PERF_EVENT_STATE_INACTIVE) | |
3085 | return 0; | |
3086 | ||
1d9b482e | 3087 | __perf_event_mark_enabled(event); |
889ff015 FW |
3088 | |
3089 | return 1; | |
3090 | } | |
3091 | ||
57e7986e | 3092 | /* |
cdd6c482 | 3093 | * Enable all of a task's events that have been marked enable-on-exec. |
57e7986e PM |
3094 | * This expects task == current. |
3095 | */ | |
c1274499 | 3096 | static void perf_event_enable_on_exec(int ctxn) |
57e7986e | 3097 | { |
c1274499 | 3098 | struct perf_event_context *ctx, *clone_ctx = NULL; |
cdd6c482 | 3099 | struct perf_event *event; |
57e7986e PM |
3100 | unsigned long flags; |
3101 | int enabled = 0; | |
889ff015 | 3102 | int ret; |
57e7986e PM |
3103 | |
3104 | local_irq_save(flags); | |
c1274499 | 3105 | ctx = current->perf_event_ctxp[ctxn]; |
cdd6c482 | 3106 | if (!ctx || !ctx->nr_events) |
57e7986e PM |
3107 | goto out; |
3108 | ||
e625cce1 | 3109 | raw_spin_lock(&ctx->lock); |
04dc2dbb | 3110 | task_ctx_sched_out(ctx); |
57e7986e | 3111 | |
b79387ef | 3112 | list_for_each_entry(event, &ctx->event_list, event_entry) { |
889ff015 FW |
3113 | ret = event_enable_on_exec(event, ctx); |
3114 | if (ret) | |
3115 | enabled = 1; | |
57e7986e PM |
3116 | } |
3117 | ||
3118 | /* | |
cdd6c482 | 3119 | * Unclone this context if we enabled any event. |
57e7986e | 3120 | */ |
71a851b4 | 3121 | if (enabled) |
211de6eb | 3122 | clone_ctx = unclone_ctx(ctx); |
57e7986e | 3123 | |
e625cce1 | 3124 | raw_spin_unlock(&ctx->lock); |
57e7986e | 3125 | |
e5d1367f | 3126 | perf_event_context_sched_in(ctx, ctx->task); |
9ed6060d | 3127 | out: |
57e7986e | 3128 | local_irq_restore(flags); |
211de6eb PZ |
3129 | |
3130 | if (clone_ctx) | |
3131 | put_ctx(clone_ctx); | |
57e7986e PM |
3132 | } |
3133 | ||
e041e328 PZ |
3134 | void perf_event_exec(void) |
3135 | { | |
e041e328 PZ |
3136 | int ctxn; |
3137 | ||
3138 | rcu_read_lock(); | |
c1274499 PZ |
3139 | for_each_task_context_nr(ctxn) |
3140 | perf_event_enable_on_exec(ctxn); | |
e041e328 PZ |
3141 | rcu_read_unlock(); |
3142 | } | |
3143 | ||
0492d4c5 PZ |
3144 | struct perf_read_data { |
3145 | struct perf_event *event; | |
3146 | bool group; | |
7d88962e | 3147 | int ret; |
0492d4c5 PZ |
3148 | }; |
3149 | ||
0793a61d | 3150 | /* |
cdd6c482 | 3151 | * Cross CPU call to read the hardware event |
0793a61d | 3152 | */ |
cdd6c482 | 3153 | static void __perf_event_read(void *info) |
0793a61d | 3154 | { |
0492d4c5 PZ |
3155 | struct perf_read_data *data = info; |
3156 | struct perf_event *sub, *event = data->event; | |
cdd6c482 | 3157 | struct perf_event_context *ctx = event->ctx; |
108b02cf | 3158 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
4a00c16e | 3159 | struct pmu *pmu = event->pmu; |
621a01ea | 3160 | |
e1ac3614 PM |
3161 | /* |
3162 | * If this is a task context, we need to check whether it is | |
3163 | * the current task context of this cpu. If not it has been | |
3164 | * scheduled out before the smp call arrived. In that case | |
cdd6c482 IM |
3165 | * event->count would have been updated to a recent sample |
3166 | * when the event was scheduled out. | |
e1ac3614 PM |
3167 | */ |
3168 | if (ctx->task && cpuctx->task_ctx != ctx) | |
3169 | return; | |
3170 | ||
e625cce1 | 3171 | raw_spin_lock(&ctx->lock); |
e5d1367f | 3172 | if (ctx->is_active) { |
542e72fc | 3173 | update_context_time(ctx); |
e5d1367f SE |
3174 | update_cgrp_time_from_event(event); |
3175 | } | |
0492d4c5 | 3176 | |
cdd6c482 | 3177 | update_event_times(event); |
4a00c16e SB |
3178 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
3179 | goto unlock; | |
0492d4c5 | 3180 | |
4a00c16e SB |
3181 | if (!data->group) { |
3182 | pmu->read(event); | |
3183 | data->ret = 0; | |
0492d4c5 | 3184 | goto unlock; |
4a00c16e SB |
3185 | } |
3186 | ||
3187 | pmu->start_txn(pmu, PERF_PMU_TXN_READ); | |
3188 | ||
3189 | pmu->read(event); | |
0492d4c5 PZ |
3190 | |
3191 | list_for_each_entry(sub, &event->sibling_list, group_entry) { | |
3192 | update_event_times(sub); | |
4a00c16e SB |
3193 | if (sub->state == PERF_EVENT_STATE_ACTIVE) { |
3194 | /* | |
3195 | * Use sibling's PMU rather than @event's since | |
3196 | * sibling could be on different (eg: software) PMU. | |
3197 | */ | |
0492d4c5 | 3198 | sub->pmu->read(sub); |
4a00c16e | 3199 | } |
0492d4c5 | 3200 | } |
4a00c16e SB |
3201 | |
3202 | data->ret = pmu->commit_txn(pmu); | |
0492d4c5 PZ |
3203 | |
3204 | unlock: | |
e625cce1 | 3205 | raw_spin_unlock(&ctx->lock); |
0793a61d TG |
3206 | } |
3207 | ||
b5e58793 PZ |
3208 | static inline u64 perf_event_count(struct perf_event *event) |
3209 | { | |
eacd3ecc MF |
3210 | if (event->pmu->count) |
3211 | return event->pmu->count(event); | |
3212 | ||
3213 | return __perf_event_count(event); | |
b5e58793 PZ |
3214 | } |
3215 | ||
ffe8690c KX |
3216 | /* |
3217 | * NMI-safe method to read a local event, that is an event that | |
3218 | * is: | |
3219 | * - either for the current task, or for this CPU | |
3220 | * - does not have inherit set, for inherited task events | |
3221 | * will not be local and we cannot read them atomically | |
3222 | * - must not have a pmu::count method | |
3223 | */ | |
3224 | u64 perf_event_read_local(struct perf_event *event) | |
3225 | { | |
3226 | unsigned long flags; | |
3227 | u64 val; | |
3228 | ||
3229 | /* | |
3230 | * Disabling interrupts avoids all counter scheduling (context | |
3231 | * switches, timer based rotation and IPIs). | |
3232 | */ | |
3233 | local_irq_save(flags); | |
3234 | ||
3235 | /* If this is a per-task event, it must be for current */ | |
3236 | WARN_ON_ONCE((event->attach_state & PERF_ATTACH_TASK) && | |
3237 | event->hw.target != current); | |
3238 | ||
3239 | /* If this is a per-CPU event, it must be for this CPU */ | |
3240 | WARN_ON_ONCE(!(event->attach_state & PERF_ATTACH_TASK) && | |
3241 | event->cpu != smp_processor_id()); | |
3242 | ||
3243 | /* | |
3244 | * It must not be an event with inherit set, we cannot read | |
3245 | * all child counters from atomic context. | |
3246 | */ | |
3247 | WARN_ON_ONCE(event->attr.inherit); | |
3248 | ||
3249 | /* | |
3250 | * It must not have a pmu::count method, those are not | |
3251 | * NMI safe. | |
3252 | */ | |
3253 | WARN_ON_ONCE(event->pmu->count); | |
3254 | ||
3255 | /* | |
3256 | * If the event is currently on this CPU, its either a per-task event, | |
3257 | * or local to this CPU. Furthermore it means its ACTIVE (otherwise | |
3258 | * oncpu == -1). | |
3259 | */ | |
3260 | if (event->oncpu == smp_processor_id()) | |
3261 | event->pmu->read(event); | |
3262 | ||
3263 | val = local64_read(&event->count); | |
3264 | local_irq_restore(flags); | |
3265 | ||
3266 | return val; | |
3267 | } | |
3268 | ||
7d88962e | 3269 | static int perf_event_read(struct perf_event *event, bool group) |
0793a61d | 3270 | { |
7d88962e SB |
3271 | int ret = 0; |
3272 | ||
0793a61d | 3273 | /* |
cdd6c482 IM |
3274 | * If event is enabled and currently active on a CPU, update the |
3275 | * value in the event structure: | |
0793a61d | 3276 | */ |
cdd6c482 | 3277 | if (event->state == PERF_EVENT_STATE_ACTIVE) { |
0492d4c5 PZ |
3278 | struct perf_read_data data = { |
3279 | .event = event, | |
3280 | .group = group, | |
7d88962e | 3281 | .ret = 0, |
0492d4c5 | 3282 | }; |
cdd6c482 | 3283 | smp_call_function_single(event->oncpu, |
0492d4c5 | 3284 | __perf_event_read, &data, 1); |
7d88962e | 3285 | ret = data.ret; |
cdd6c482 | 3286 | } else if (event->state == PERF_EVENT_STATE_INACTIVE) { |
2b8988c9 PZ |
3287 | struct perf_event_context *ctx = event->ctx; |
3288 | unsigned long flags; | |
3289 | ||
e625cce1 | 3290 | raw_spin_lock_irqsave(&ctx->lock, flags); |
c530ccd9 SE |
3291 | /* |
3292 | * may read while context is not active | |
3293 | * (e.g., thread is blocked), in that case | |
3294 | * we cannot update context time | |
3295 | */ | |
e5d1367f | 3296 | if (ctx->is_active) { |
c530ccd9 | 3297 | update_context_time(ctx); |
e5d1367f SE |
3298 | update_cgrp_time_from_event(event); |
3299 | } | |
0492d4c5 PZ |
3300 | if (group) |
3301 | update_group_times(event); | |
3302 | else | |
3303 | update_event_times(event); | |
e625cce1 | 3304 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
0793a61d | 3305 | } |
7d88962e SB |
3306 | |
3307 | return ret; | |
0793a61d TG |
3308 | } |
3309 | ||
a63eaf34 | 3310 | /* |
cdd6c482 | 3311 | * Initialize the perf_event context in a task_struct: |
a63eaf34 | 3312 | */ |
eb184479 | 3313 | static void __perf_event_init_context(struct perf_event_context *ctx) |
a63eaf34 | 3314 | { |
e625cce1 | 3315 | raw_spin_lock_init(&ctx->lock); |
a63eaf34 | 3316 | mutex_init(&ctx->mutex); |
2fde4f94 | 3317 | INIT_LIST_HEAD(&ctx->active_ctx_list); |
889ff015 FW |
3318 | INIT_LIST_HEAD(&ctx->pinned_groups); |
3319 | INIT_LIST_HEAD(&ctx->flexible_groups); | |
a63eaf34 PM |
3320 | INIT_LIST_HEAD(&ctx->event_list); |
3321 | atomic_set(&ctx->refcount, 1); | |
fadfe7be | 3322 | INIT_DELAYED_WORK(&ctx->orphans_remove, orphans_remove_work); |
eb184479 PZ |
3323 | } |
3324 | ||
3325 | static struct perf_event_context * | |
3326 | alloc_perf_context(struct pmu *pmu, struct task_struct *task) | |
3327 | { | |
3328 | struct perf_event_context *ctx; | |
3329 | ||
3330 | ctx = kzalloc(sizeof(struct perf_event_context), GFP_KERNEL); | |
3331 | if (!ctx) | |
3332 | return NULL; | |
3333 | ||
3334 | __perf_event_init_context(ctx); | |
3335 | if (task) { | |
3336 | ctx->task = task; | |
3337 | get_task_struct(task); | |
0793a61d | 3338 | } |
eb184479 PZ |
3339 | ctx->pmu = pmu; |
3340 | ||
3341 | return ctx; | |
a63eaf34 PM |
3342 | } |
3343 | ||
2ebd4ffb MH |
3344 | static struct task_struct * |
3345 | find_lively_task_by_vpid(pid_t vpid) | |
3346 | { | |
3347 | struct task_struct *task; | |
3348 | int err; | |
0793a61d TG |
3349 | |
3350 | rcu_read_lock(); | |
2ebd4ffb | 3351 | if (!vpid) |
0793a61d TG |
3352 | task = current; |
3353 | else | |
2ebd4ffb | 3354 | task = find_task_by_vpid(vpid); |
0793a61d TG |
3355 | if (task) |
3356 | get_task_struct(task); | |
3357 | rcu_read_unlock(); | |
3358 | ||
3359 | if (!task) | |
3360 | return ERR_PTR(-ESRCH); | |
3361 | ||
0793a61d | 3362 | /* Reuse ptrace permission checks for now. */ |
c93f7669 PM |
3363 | err = -EACCES; |
3364 | if (!ptrace_may_access(task, PTRACE_MODE_READ)) | |
3365 | goto errout; | |
3366 | ||
2ebd4ffb MH |
3367 | return task; |
3368 | errout: | |
3369 | put_task_struct(task); | |
3370 | return ERR_PTR(err); | |
3371 | ||
3372 | } | |
3373 | ||
fe4b04fa PZ |
3374 | /* |
3375 | * Returns a matching context with refcount and pincount. | |
3376 | */ | |
108b02cf | 3377 | static struct perf_event_context * |
4af57ef2 YZ |
3378 | find_get_context(struct pmu *pmu, struct task_struct *task, |
3379 | struct perf_event *event) | |
0793a61d | 3380 | { |
211de6eb | 3381 | struct perf_event_context *ctx, *clone_ctx = NULL; |
22a4f650 | 3382 | struct perf_cpu_context *cpuctx; |
4af57ef2 | 3383 | void *task_ctx_data = NULL; |
25346b93 | 3384 | unsigned long flags; |
8dc85d54 | 3385 | int ctxn, err; |
4af57ef2 | 3386 | int cpu = event->cpu; |
0793a61d | 3387 | |
22a4ec72 | 3388 | if (!task) { |
cdd6c482 | 3389 | /* Must be root to operate on a CPU event: */ |
0764771d | 3390 | if (perf_paranoid_cpu() && !capable(CAP_SYS_ADMIN)) |
0793a61d TG |
3391 | return ERR_PTR(-EACCES); |
3392 | ||
0793a61d | 3393 | /* |
cdd6c482 | 3394 | * We could be clever and allow to attach a event to an |
0793a61d TG |
3395 | * offline CPU and activate it when the CPU comes up, but |
3396 | * that's for later. | |
3397 | */ | |
f6325e30 | 3398 | if (!cpu_online(cpu)) |
0793a61d TG |
3399 | return ERR_PTR(-ENODEV); |
3400 | ||
108b02cf | 3401 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); |
0793a61d | 3402 | ctx = &cpuctx->ctx; |
c93f7669 | 3403 | get_ctx(ctx); |
fe4b04fa | 3404 | ++ctx->pin_count; |
0793a61d | 3405 | |
0793a61d TG |
3406 | return ctx; |
3407 | } | |
3408 | ||
8dc85d54 PZ |
3409 | err = -EINVAL; |
3410 | ctxn = pmu->task_ctx_nr; | |
3411 | if (ctxn < 0) | |
3412 | goto errout; | |
3413 | ||
4af57ef2 YZ |
3414 | if (event->attach_state & PERF_ATTACH_TASK_DATA) { |
3415 | task_ctx_data = kzalloc(pmu->task_ctx_size, GFP_KERNEL); | |
3416 | if (!task_ctx_data) { | |
3417 | err = -ENOMEM; | |
3418 | goto errout; | |
3419 | } | |
3420 | } | |
3421 | ||
9ed6060d | 3422 | retry: |
8dc85d54 | 3423 | ctx = perf_lock_task_context(task, ctxn, &flags); |
c93f7669 | 3424 | if (ctx) { |
211de6eb | 3425 | clone_ctx = unclone_ctx(ctx); |
fe4b04fa | 3426 | ++ctx->pin_count; |
4af57ef2 YZ |
3427 | |
3428 | if (task_ctx_data && !ctx->task_ctx_data) { | |
3429 | ctx->task_ctx_data = task_ctx_data; | |
3430 | task_ctx_data = NULL; | |
3431 | } | |
e625cce1 | 3432 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
211de6eb PZ |
3433 | |
3434 | if (clone_ctx) | |
3435 | put_ctx(clone_ctx); | |
9137fb28 | 3436 | } else { |
eb184479 | 3437 | ctx = alloc_perf_context(pmu, task); |
c93f7669 PM |
3438 | err = -ENOMEM; |
3439 | if (!ctx) | |
3440 | goto errout; | |
eb184479 | 3441 | |
4af57ef2 YZ |
3442 | if (task_ctx_data) { |
3443 | ctx->task_ctx_data = task_ctx_data; | |
3444 | task_ctx_data = NULL; | |
3445 | } | |
3446 | ||
dbe08d82 ON |
3447 | err = 0; |
3448 | mutex_lock(&task->perf_event_mutex); | |
3449 | /* | |
3450 | * If it has already passed perf_event_exit_task(). | |
3451 | * we must see PF_EXITING, it takes this mutex too. | |
3452 | */ | |
3453 | if (task->flags & PF_EXITING) | |
3454 | err = -ESRCH; | |
3455 | else if (task->perf_event_ctxp[ctxn]) | |
3456 | err = -EAGAIN; | |
fe4b04fa | 3457 | else { |
9137fb28 | 3458 | get_ctx(ctx); |
fe4b04fa | 3459 | ++ctx->pin_count; |
dbe08d82 | 3460 | rcu_assign_pointer(task->perf_event_ctxp[ctxn], ctx); |
fe4b04fa | 3461 | } |
dbe08d82 ON |
3462 | mutex_unlock(&task->perf_event_mutex); |
3463 | ||
3464 | if (unlikely(err)) { | |
9137fb28 | 3465 | put_ctx(ctx); |
dbe08d82 ON |
3466 | |
3467 | if (err == -EAGAIN) | |
3468 | goto retry; | |
3469 | goto errout; | |
a63eaf34 PM |
3470 | } |
3471 | } | |
3472 | ||
4af57ef2 | 3473 | kfree(task_ctx_data); |
0793a61d | 3474 | return ctx; |
c93f7669 | 3475 | |
9ed6060d | 3476 | errout: |
4af57ef2 | 3477 | kfree(task_ctx_data); |
c93f7669 | 3478 | return ERR_PTR(err); |
0793a61d TG |
3479 | } |
3480 | ||
6fb2915d | 3481 | static void perf_event_free_filter(struct perf_event *event); |
2541517c | 3482 | static void perf_event_free_bpf_prog(struct perf_event *event); |
6fb2915d | 3483 | |
cdd6c482 | 3484 | static void free_event_rcu(struct rcu_head *head) |
592903cd | 3485 | { |
cdd6c482 | 3486 | struct perf_event *event; |
592903cd | 3487 | |
cdd6c482 IM |
3488 | event = container_of(head, struct perf_event, rcu_head); |
3489 | if (event->ns) | |
3490 | put_pid_ns(event->ns); | |
6fb2915d | 3491 | perf_event_free_filter(event); |
cdd6c482 | 3492 | kfree(event); |
592903cd PZ |
3493 | } |
3494 | ||
b69cf536 PZ |
3495 | static void ring_buffer_attach(struct perf_event *event, |
3496 | struct ring_buffer *rb); | |
925d519a | 3497 | |
4beb31f3 | 3498 | static void unaccount_event_cpu(struct perf_event *event, int cpu) |
f1600952 | 3499 | { |
4beb31f3 FW |
3500 | if (event->parent) |
3501 | return; | |
3502 | ||
4beb31f3 FW |
3503 | if (is_cgroup_event(event)) |
3504 | atomic_dec(&per_cpu(perf_cgroup_events, cpu)); | |
3505 | } | |
925d519a | 3506 | |
4beb31f3 FW |
3507 | static void unaccount_event(struct perf_event *event) |
3508 | { | |
3509 | if (event->parent) | |
3510 | return; | |
3511 | ||
3512 | if (event->attach_state & PERF_ATTACH_TASK) | |
3513 | static_key_slow_dec_deferred(&perf_sched_events); | |
3514 | if (event->attr.mmap || event->attr.mmap_data) | |
3515 | atomic_dec(&nr_mmap_events); | |
3516 | if (event->attr.comm) | |
3517 | atomic_dec(&nr_comm_events); | |
3518 | if (event->attr.task) | |
3519 | atomic_dec(&nr_task_events); | |
948b26b6 FW |
3520 | if (event->attr.freq) |
3521 | atomic_dec(&nr_freq_events); | |
45ac1403 AH |
3522 | if (event->attr.context_switch) { |
3523 | static_key_slow_dec_deferred(&perf_sched_events); | |
3524 | atomic_dec(&nr_switch_events); | |
3525 | } | |
4beb31f3 FW |
3526 | if (is_cgroup_event(event)) |
3527 | static_key_slow_dec_deferred(&perf_sched_events); | |
3528 | if (has_branch_stack(event)) | |
3529 | static_key_slow_dec_deferred(&perf_sched_events); | |
3530 | ||
3531 | unaccount_event_cpu(event, event->cpu); | |
3532 | } | |
925d519a | 3533 | |
bed5b25a AS |
3534 | /* |
3535 | * The following implement mutual exclusion of events on "exclusive" pmus | |
3536 | * (PERF_PMU_CAP_EXCLUSIVE). Such pmus can only have one event scheduled | |
3537 | * at a time, so we disallow creating events that might conflict, namely: | |
3538 | * | |
3539 | * 1) cpu-wide events in the presence of per-task events, | |
3540 | * 2) per-task events in the presence of cpu-wide events, | |
3541 | * 3) two matching events on the same context. | |
3542 | * | |
3543 | * The former two cases are handled in the allocation path (perf_event_alloc(), | |
3544 | * __free_event()), the latter -- before the first perf_install_in_context(). | |
3545 | */ | |
3546 | static int exclusive_event_init(struct perf_event *event) | |
3547 | { | |
3548 | struct pmu *pmu = event->pmu; | |
3549 | ||
3550 | if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE)) | |
3551 | return 0; | |
3552 | ||
3553 | /* | |
3554 | * Prevent co-existence of per-task and cpu-wide events on the | |
3555 | * same exclusive pmu. | |
3556 | * | |
3557 | * Negative pmu::exclusive_cnt means there are cpu-wide | |
3558 | * events on this "exclusive" pmu, positive means there are | |
3559 | * per-task events. | |
3560 | * | |
3561 | * Since this is called in perf_event_alloc() path, event::ctx | |
3562 | * doesn't exist yet; it is, however, safe to use PERF_ATTACH_TASK | |
3563 | * to mean "per-task event", because unlike other attach states it | |
3564 | * never gets cleared. | |
3565 | */ | |
3566 | if (event->attach_state & PERF_ATTACH_TASK) { | |
3567 | if (!atomic_inc_unless_negative(&pmu->exclusive_cnt)) | |
3568 | return -EBUSY; | |
3569 | } else { | |
3570 | if (!atomic_dec_unless_positive(&pmu->exclusive_cnt)) | |
3571 | return -EBUSY; | |
3572 | } | |
3573 | ||
3574 | return 0; | |
3575 | } | |
3576 | ||
3577 | static void exclusive_event_destroy(struct perf_event *event) | |
3578 | { | |
3579 | struct pmu *pmu = event->pmu; | |
3580 | ||
3581 | if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE)) | |
3582 | return; | |
3583 | ||
3584 | /* see comment in exclusive_event_init() */ | |
3585 | if (event->attach_state & PERF_ATTACH_TASK) | |
3586 | atomic_dec(&pmu->exclusive_cnt); | |
3587 | else | |
3588 | atomic_inc(&pmu->exclusive_cnt); | |
3589 | } | |
3590 | ||
3591 | static bool exclusive_event_match(struct perf_event *e1, struct perf_event *e2) | |
3592 | { | |
3593 | if ((e1->pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE) && | |
3594 | (e1->cpu == e2->cpu || | |
3595 | e1->cpu == -1 || | |
3596 | e2->cpu == -1)) | |
3597 | return true; | |
3598 | return false; | |
3599 | } | |
3600 | ||
3601 | /* Called under the same ctx::mutex as perf_install_in_context() */ | |
3602 | static bool exclusive_event_installable(struct perf_event *event, | |
3603 | struct perf_event_context *ctx) | |
3604 | { | |
3605 | struct perf_event *iter_event; | |
3606 | struct pmu *pmu = event->pmu; | |
3607 | ||
3608 | if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE)) | |
3609 | return true; | |
3610 | ||
3611 | list_for_each_entry(iter_event, &ctx->event_list, event_entry) { | |
3612 | if (exclusive_event_match(iter_event, event)) | |
3613 | return false; | |
3614 | } | |
3615 | ||
3616 | return true; | |
3617 | } | |
3618 | ||
766d6c07 FW |
3619 | static void __free_event(struct perf_event *event) |
3620 | { | |
cdd6c482 | 3621 | if (!event->parent) { |
927c7a9e FW |
3622 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) |
3623 | put_callchain_buffers(); | |
f344011c | 3624 | } |
9ee318a7 | 3625 | |
dead9f29 AS |
3626 | perf_event_free_bpf_prog(event); |
3627 | ||
766d6c07 FW |
3628 | if (event->destroy) |
3629 | event->destroy(event); | |
3630 | ||
3631 | if (event->ctx) | |
3632 | put_ctx(event->ctx); | |
3633 | ||
bed5b25a AS |
3634 | if (event->pmu) { |
3635 | exclusive_event_destroy(event); | |
c464c76e | 3636 | module_put(event->pmu->module); |
bed5b25a | 3637 | } |
c464c76e | 3638 | |
766d6c07 FW |
3639 | call_rcu(&event->rcu_head, free_event_rcu); |
3640 | } | |
683ede43 PZ |
3641 | |
3642 | static void _free_event(struct perf_event *event) | |
f1600952 | 3643 | { |
e360adbe | 3644 | irq_work_sync(&event->pending); |
925d519a | 3645 | |
4beb31f3 | 3646 | unaccount_event(event); |
9ee318a7 | 3647 | |
76369139 | 3648 | if (event->rb) { |
9bb5d40c PZ |
3649 | /* |
3650 | * Can happen when we close an event with re-directed output. | |
3651 | * | |
3652 | * Since we have a 0 refcount, perf_mmap_close() will skip | |
3653 | * over us; possibly making our ring_buffer_put() the last. | |
3654 | */ | |
3655 | mutex_lock(&event->mmap_mutex); | |
b69cf536 | 3656 | ring_buffer_attach(event, NULL); |
9bb5d40c | 3657 | mutex_unlock(&event->mmap_mutex); |
a4be7c27 PZ |
3658 | } |
3659 | ||
e5d1367f SE |
3660 | if (is_cgroup_event(event)) |
3661 | perf_detach_cgroup(event); | |
3662 | ||
766d6c07 | 3663 | __free_event(event); |
f1600952 PZ |
3664 | } |
3665 | ||
683ede43 PZ |
3666 | /* |
3667 | * Used to free events which have a known refcount of 1, such as in error paths | |
3668 | * where the event isn't exposed yet and inherited events. | |
3669 | */ | |
3670 | static void free_event(struct perf_event *event) | |
0793a61d | 3671 | { |
683ede43 PZ |
3672 | if (WARN(atomic_long_cmpxchg(&event->refcount, 1, 0) != 1, |
3673 | "unexpected event refcount: %ld; ptr=%p\n", | |
3674 | atomic_long_read(&event->refcount), event)) { | |
3675 | /* leak to avoid use-after-free */ | |
3676 | return; | |
3677 | } | |
0793a61d | 3678 | |
683ede43 | 3679 | _free_event(event); |
0793a61d TG |
3680 | } |
3681 | ||
a66a3052 | 3682 | /* |
f8697762 | 3683 | * Remove user event from the owner task. |
a66a3052 | 3684 | */ |
f8697762 | 3685 | static void perf_remove_from_owner(struct perf_event *event) |
fb0459d7 | 3686 | { |
8882135b | 3687 | struct task_struct *owner; |
fb0459d7 | 3688 | |
8882135b PZ |
3689 | rcu_read_lock(); |
3690 | owner = ACCESS_ONCE(event->owner); | |
3691 | /* | |
3692 | * Matches the smp_wmb() in perf_event_exit_task(). If we observe | |
3693 | * !owner it means the list deletion is complete and we can indeed | |
3694 | * free this event, otherwise we need to serialize on | |
3695 | * owner->perf_event_mutex. | |
3696 | */ | |
3697 | smp_read_barrier_depends(); | |
3698 | if (owner) { | |
3699 | /* | |
3700 | * Since delayed_put_task_struct() also drops the last | |
3701 | * task reference we can safely take a new reference | |
3702 | * while holding the rcu_read_lock(). | |
3703 | */ | |
3704 | get_task_struct(owner); | |
3705 | } | |
3706 | rcu_read_unlock(); | |
3707 | ||
3708 | if (owner) { | |
f63a8daa PZ |
3709 | /* |
3710 | * If we're here through perf_event_exit_task() we're already | |
3711 | * holding ctx->mutex which would be an inversion wrt. the | |
3712 | * normal lock order. | |
3713 | * | |
3714 | * However we can safely take this lock because its the child | |
3715 | * ctx->mutex. | |
3716 | */ | |
3717 | mutex_lock_nested(&owner->perf_event_mutex, SINGLE_DEPTH_NESTING); | |
3718 | ||
8882135b PZ |
3719 | /* |
3720 | * We have to re-check the event->owner field, if it is cleared | |
3721 | * we raced with perf_event_exit_task(), acquiring the mutex | |
3722 | * ensured they're done, and we can proceed with freeing the | |
3723 | * event. | |
3724 | */ | |
3725 | if (event->owner) | |
3726 | list_del_init(&event->owner_entry); | |
3727 | mutex_unlock(&owner->perf_event_mutex); | |
3728 | put_task_struct(owner); | |
3729 | } | |
f8697762 JO |
3730 | } |
3731 | ||
f8697762 JO |
3732 | static void put_event(struct perf_event *event) |
3733 | { | |
a83fe28e | 3734 | struct perf_event_context *ctx; |
f8697762 JO |
3735 | |
3736 | if (!atomic_long_dec_and_test(&event->refcount)) | |
3737 | return; | |
3738 | ||
3739 | if (!is_kernel_event(event)) | |
3740 | perf_remove_from_owner(event); | |
8882135b | 3741 | |
683ede43 PZ |
3742 | /* |
3743 | * There are two ways this annotation is useful: | |
3744 | * | |
3745 | * 1) there is a lock recursion from perf_event_exit_task | |
3746 | * see the comment there. | |
3747 | * | |
3748 | * 2) there is a lock-inversion with mmap_sem through | |
b15f495b | 3749 | * perf_read_group(), which takes faults while |
683ede43 PZ |
3750 | * holding ctx->mutex, however this is called after |
3751 | * the last filedesc died, so there is no possibility | |
3752 | * to trigger the AB-BA case. | |
3753 | */ | |
a83fe28e PZ |
3754 | ctx = perf_event_ctx_lock_nested(event, SINGLE_DEPTH_NESTING); |
3755 | WARN_ON_ONCE(ctx->parent_ctx); | |
683ede43 | 3756 | perf_remove_from_context(event, true); |
d415a7f1 | 3757 | perf_event_ctx_unlock(event, ctx); |
683ede43 PZ |
3758 | |
3759 | _free_event(event); | |
a6fa941d AV |
3760 | } |
3761 | ||
683ede43 PZ |
3762 | int perf_event_release_kernel(struct perf_event *event) |
3763 | { | |
3764 | put_event(event); | |
3765 | return 0; | |
3766 | } | |
3767 | EXPORT_SYMBOL_GPL(perf_event_release_kernel); | |
3768 | ||
8b10c5e2 PZ |
3769 | /* |
3770 | * Called when the last reference to the file is gone. | |
3771 | */ | |
a6fa941d AV |
3772 | static int perf_release(struct inode *inode, struct file *file) |
3773 | { | |
3774 | put_event(file->private_data); | |
3775 | return 0; | |
fb0459d7 | 3776 | } |
fb0459d7 | 3777 | |
fadfe7be JO |
3778 | /* |
3779 | * Remove all orphanes events from the context. | |
3780 | */ | |
3781 | static void orphans_remove_work(struct work_struct *work) | |
3782 | { | |
3783 | struct perf_event_context *ctx; | |
3784 | struct perf_event *event, *tmp; | |
3785 | ||
3786 | ctx = container_of(work, struct perf_event_context, | |
3787 | orphans_remove.work); | |
3788 | ||
3789 | mutex_lock(&ctx->mutex); | |
3790 | list_for_each_entry_safe(event, tmp, &ctx->event_list, event_entry) { | |
3791 | struct perf_event *parent_event = event->parent; | |
3792 | ||
3793 | if (!is_orphaned_child(event)) | |
3794 | continue; | |
3795 | ||
3796 | perf_remove_from_context(event, true); | |
3797 | ||
3798 | mutex_lock(&parent_event->child_mutex); | |
3799 | list_del_init(&event->child_list); | |
3800 | mutex_unlock(&parent_event->child_mutex); | |
3801 | ||
3802 | free_event(event); | |
3803 | put_event(parent_event); | |
3804 | } | |
3805 | ||
3806 | raw_spin_lock_irq(&ctx->lock); | |
3807 | ctx->orphans_remove_sched = false; | |
3808 | raw_spin_unlock_irq(&ctx->lock); | |
3809 | mutex_unlock(&ctx->mutex); | |
3810 | ||
3811 | put_ctx(ctx); | |
3812 | } | |
3813 | ||
59ed446f | 3814 | u64 perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) |
e53c0994 | 3815 | { |
cdd6c482 | 3816 | struct perf_event *child; |
e53c0994 PZ |
3817 | u64 total = 0; |
3818 | ||
59ed446f PZ |
3819 | *enabled = 0; |
3820 | *running = 0; | |
3821 | ||
6f10581a | 3822 | mutex_lock(&event->child_mutex); |
01add3ea | 3823 | |
7d88962e | 3824 | (void)perf_event_read(event, false); |
01add3ea SB |
3825 | total += perf_event_count(event); |
3826 | ||
59ed446f PZ |
3827 | *enabled += event->total_time_enabled + |
3828 | atomic64_read(&event->child_total_time_enabled); | |
3829 | *running += event->total_time_running + | |
3830 | atomic64_read(&event->child_total_time_running); | |
3831 | ||
3832 | list_for_each_entry(child, &event->child_list, child_list) { | |
7d88962e | 3833 | (void)perf_event_read(child, false); |
01add3ea | 3834 | total += perf_event_count(child); |
59ed446f PZ |
3835 | *enabled += child->total_time_enabled; |
3836 | *running += child->total_time_running; | |
3837 | } | |
6f10581a | 3838 | mutex_unlock(&event->child_mutex); |
e53c0994 PZ |
3839 | |
3840 | return total; | |
3841 | } | |
fb0459d7 | 3842 | EXPORT_SYMBOL_GPL(perf_event_read_value); |
e53c0994 | 3843 | |
7d88962e | 3844 | static int __perf_read_group_add(struct perf_event *leader, |
fa8c2693 | 3845 | u64 read_format, u64 *values) |
3dab77fb | 3846 | { |
fa8c2693 PZ |
3847 | struct perf_event *sub; |
3848 | int n = 1; /* skip @nr */ | |
7d88962e | 3849 | int ret; |
f63a8daa | 3850 | |
7d88962e SB |
3851 | ret = perf_event_read(leader, true); |
3852 | if (ret) | |
3853 | return ret; | |
abf4868b | 3854 | |
fa8c2693 PZ |
3855 | /* |
3856 | * Since we co-schedule groups, {enabled,running} times of siblings | |
3857 | * will be identical to those of the leader, so we only publish one | |
3858 | * set. | |
3859 | */ | |
3860 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { | |
3861 | values[n++] += leader->total_time_enabled + | |
3862 | atomic64_read(&leader->child_total_time_enabled); | |
3863 | } | |
3dab77fb | 3864 | |
fa8c2693 PZ |
3865 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { |
3866 | values[n++] += leader->total_time_running + | |
3867 | atomic64_read(&leader->child_total_time_running); | |
3868 | } | |
3869 | ||
3870 | /* | |
3871 | * Write {count,id} tuples for every sibling. | |
3872 | */ | |
3873 | values[n++] += perf_event_count(leader); | |
abf4868b PZ |
3874 | if (read_format & PERF_FORMAT_ID) |
3875 | values[n++] = primary_event_id(leader); | |
3dab77fb | 3876 | |
fa8c2693 PZ |
3877 | list_for_each_entry(sub, &leader->sibling_list, group_entry) { |
3878 | values[n++] += perf_event_count(sub); | |
3879 | if (read_format & PERF_FORMAT_ID) | |
3880 | values[n++] = primary_event_id(sub); | |
3881 | } | |
7d88962e SB |
3882 | |
3883 | return 0; | |
fa8c2693 | 3884 | } |
3dab77fb | 3885 | |
fa8c2693 PZ |
3886 | static int perf_read_group(struct perf_event *event, |
3887 | u64 read_format, char __user *buf) | |
3888 | { | |
3889 | struct perf_event *leader = event->group_leader, *child; | |
3890 | struct perf_event_context *ctx = leader->ctx; | |
7d88962e | 3891 | int ret; |
fa8c2693 | 3892 | u64 *values; |
3dab77fb | 3893 | |
fa8c2693 | 3894 | lockdep_assert_held(&ctx->mutex); |
3dab77fb | 3895 | |
fa8c2693 PZ |
3896 | values = kzalloc(event->read_size, GFP_KERNEL); |
3897 | if (!values) | |
3898 | return -ENOMEM; | |
3dab77fb | 3899 | |
fa8c2693 PZ |
3900 | values[0] = 1 + leader->nr_siblings; |
3901 | ||
3902 | /* | |
3903 | * By locking the child_mutex of the leader we effectively | |
3904 | * lock the child list of all siblings.. XXX explain how. | |
3905 | */ | |
3906 | mutex_lock(&leader->child_mutex); | |
abf4868b | 3907 | |
7d88962e SB |
3908 | ret = __perf_read_group_add(leader, read_format, values); |
3909 | if (ret) | |
3910 | goto unlock; | |
3911 | ||
3912 | list_for_each_entry(child, &leader->child_list, child_list) { | |
3913 | ret = __perf_read_group_add(child, read_format, values); | |
3914 | if (ret) | |
3915 | goto unlock; | |
3916 | } | |
abf4868b | 3917 | |
fa8c2693 | 3918 | mutex_unlock(&leader->child_mutex); |
abf4868b | 3919 | |
7d88962e | 3920 | ret = event->read_size; |
fa8c2693 PZ |
3921 | if (copy_to_user(buf, values, event->read_size)) |
3922 | ret = -EFAULT; | |
7d88962e | 3923 | goto out; |
fa8c2693 | 3924 | |
7d88962e SB |
3925 | unlock: |
3926 | mutex_unlock(&leader->child_mutex); | |
3927 | out: | |
fa8c2693 | 3928 | kfree(values); |
abf4868b | 3929 | return ret; |
3dab77fb PZ |
3930 | } |
3931 | ||
b15f495b | 3932 | static int perf_read_one(struct perf_event *event, |
3dab77fb PZ |
3933 | u64 read_format, char __user *buf) |
3934 | { | |
59ed446f | 3935 | u64 enabled, running; |
3dab77fb PZ |
3936 | u64 values[4]; |
3937 | int n = 0; | |
3938 | ||
59ed446f PZ |
3939 | values[n++] = perf_event_read_value(event, &enabled, &running); |
3940 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
3941 | values[n++] = enabled; | |
3942 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
3943 | values[n++] = running; | |
3dab77fb | 3944 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 3945 | values[n++] = primary_event_id(event); |
3dab77fb PZ |
3946 | |
3947 | if (copy_to_user(buf, values, n * sizeof(u64))) | |
3948 | return -EFAULT; | |
3949 | ||
3950 | return n * sizeof(u64); | |
3951 | } | |
3952 | ||
dc633982 JO |
3953 | static bool is_event_hup(struct perf_event *event) |
3954 | { | |
3955 | bool no_children; | |
3956 | ||
3957 | if (event->state != PERF_EVENT_STATE_EXIT) | |
3958 | return false; | |
3959 | ||
3960 | mutex_lock(&event->child_mutex); | |
3961 | no_children = list_empty(&event->child_list); | |
3962 | mutex_unlock(&event->child_mutex); | |
3963 | return no_children; | |
3964 | } | |
3965 | ||
0793a61d | 3966 | /* |
cdd6c482 | 3967 | * Read the performance event - simple non blocking version for now |
0793a61d TG |
3968 | */ |
3969 | static ssize_t | |
b15f495b | 3970 | __perf_read(struct perf_event *event, char __user *buf, size_t count) |
0793a61d | 3971 | { |
cdd6c482 | 3972 | u64 read_format = event->attr.read_format; |
3dab77fb | 3973 | int ret; |
0793a61d | 3974 | |
3b6f9e5c | 3975 | /* |
cdd6c482 | 3976 | * Return end-of-file for a read on a event that is in |
3b6f9e5c PM |
3977 | * error state (i.e. because it was pinned but it couldn't be |
3978 | * scheduled on to the CPU at some point). | |
3979 | */ | |
cdd6c482 | 3980 | if (event->state == PERF_EVENT_STATE_ERROR) |
3b6f9e5c PM |
3981 | return 0; |
3982 | ||
c320c7b7 | 3983 | if (count < event->read_size) |
3dab77fb PZ |
3984 | return -ENOSPC; |
3985 | ||
cdd6c482 | 3986 | WARN_ON_ONCE(event->ctx->parent_ctx); |
3dab77fb | 3987 | if (read_format & PERF_FORMAT_GROUP) |
b15f495b | 3988 | ret = perf_read_group(event, read_format, buf); |
3dab77fb | 3989 | else |
b15f495b | 3990 | ret = perf_read_one(event, read_format, buf); |
0793a61d | 3991 | |
3dab77fb | 3992 | return ret; |
0793a61d TG |
3993 | } |
3994 | ||
0793a61d TG |
3995 | static ssize_t |
3996 | perf_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) | |
3997 | { | |
cdd6c482 | 3998 | struct perf_event *event = file->private_data; |
f63a8daa PZ |
3999 | struct perf_event_context *ctx; |
4000 | int ret; | |
0793a61d | 4001 | |
f63a8daa | 4002 | ctx = perf_event_ctx_lock(event); |
b15f495b | 4003 | ret = __perf_read(event, buf, count); |
f63a8daa PZ |
4004 | perf_event_ctx_unlock(event, ctx); |
4005 | ||
4006 | return ret; | |
0793a61d TG |
4007 | } |
4008 | ||
4009 | static unsigned int perf_poll(struct file *file, poll_table *wait) | |
4010 | { | |
cdd6c482 | 4011 | struct perf_event *event = file->private_data; |
76369139 | 4012 | struct ring_buffer *rb; |
61b67684 | 4013 | unsigned int events = POLLHUP; |
c7138f37 | 4014 | |
e708d7ad | 4015 | poll_wait(file, &event->waitq, wait); |
179033b3 | 4016 | |
dc633982 | 4017 | if (is_event_hup(event)) |
179033b3 | 4018 | return events; |
c7138f37 | 4019 | |
10c6db11 | 4020 | /* |
9bb5d40c PZ |
4021 | * Pin the event->rb by taking event->mmap_mutex; otherwise |
4022 | * perf_event_set_output() can swizzle our rb and make us miss wakeups. | |
10c6db11 PZ |
4023 | */ |
4024 | mutex_lock(&event->mmap_mutex); | |
9bb5d40c PZ |
4025 | rb = event->rb; |
4026 | if (rb) | |
76369139 | 4027 | events = atomic_xchg(&rb->poll, 0); |
10c6db11 | 4028 | mutex_unlock(&event->mmap_mutex); |
0793a61d TG |
4029 | return events; |
4030 | } | |
4031 | ||
f63a8daa | 4032 | static void _perf_event_reset(struct perf_event *event) |
6de6a7b9 | 4033 | { |
7d88962e | 4034 | (void)perf_event_read(event, false); |
e7850595 | 4035 | local64_set(&event->count, 0); |
cdd6c482 | 4036 | perf_event_update_userpage(event); |
3df5edad PZ |
4037 | } |
4038 | ||
c93f7669 | 4039 | /* |
cdd6c482 IM |
4040 | * Holding the top-level event's child_mutex means that any |
4041 | * descendant process that has inherited this event will block | |
4042 | * in sync_child_event if it goes to exit, thus satisfying the | |
4043 | * task existence requirements of perf_event_enable/disable. | |
c93f7669 | 4044 | */ |
cdd6c482 IM |
4045 | static void perf_event_for_each_child(struct perf_event *event, |
4046 | void (*func)(struct perf_event *)) | |
3df5edad | 4047 | { |
cdd6c482 | 4048 | struct perf_event *child; |
3df5edad | 4049 | |
cdd6c482 | 4050 | WARN_ON_ONCE(event->ctx->parent_ctx); |
f63a8daa | 4051 | |
cdd6c482 IM |
4052 | mutex_lock(&event->child_mutex); |
4053 | func(event); | |
4054 | list_for_each_entry(child, &event->child_list, child_list) | |
3df5edad | 4055 | func(child); |
cdd6c482 | 4056 | mutex_unlock(&event->child_mutex); |
3df5edad PZ |
4057 | } |
4058 | ||
cdd6c482 IM |
4059 | static void perf_event_for_each(struct perf_event *event, |
4060 | void (*func)(struct perf_event *)) | |
3df5edad | 4061 | { |
cdd6c482 IM |
4062 | struct perf_event_context *ctx = event->ctx; |
4063 | struct perf_event *sibling; | |
3df5edad | 4064 | |
f63a8daa PZ |
4065 | lockdep_assert_held(&ctx->mutex); |
4066 | ||
cdd6c482 | 4067 | event = event->group_leader; |
75f937f2 | 4068 | |
cdd6c482 | 4069 | perf_event_for_each_child(event, func); |
cdd6c482 | 4070 | list_for_each_entry(sibling, &event->sibling_list, group_entry) |
724b6daa | 4071 | perf_event_for_each_child(sibling, func); |
6de6a7b9 PZ |
4072 | } |
4073 | ||
c7999c6f PZ |
4074 | struct period_event { |
4075 | struct perf_event *event; | |
08247e31 | 4076 | u64 value; |
c7999c6f | 4077 | }; |
08247e31 | 4078 | |
0017960f PZ |
4079 | static void ___perf_event_period(void *info) |
4080 | { | |
4081 | struct period_event *pe = info; | |
4082 | struct perf_event *event = pe->event; | |
4083 | u64 value = pe->value; | |
4084 | ||
4085 | if (event->attr.freq) { | |
4086 | event->attr.sample_freq = value; | |
4087 | } else { | |
4088 | event->attr.sample_period = value; | |
4089 | event->hw.sample_period = value; | |
4090 | } | |
4091 | ||
4092 | local64_set(&event->hw.period_left, 0); | |
4093 | } | |
4094 | ||
c7999c6f PZ |
4095 | static int __perf_event_period(void *info) |
4096 | { | |
4097 | struct period_event *pe = info; | |
4098 | struct perf_event *event = pe->event; | |
4099 | struct perf_event_context *ctx = event->ctx; | |
4100 | u64 value = pe->value; | |
4101 | bool active; | |
08247e31 | 4102 | |
c7999c6f | 4103 | raw_spin_lock(&ctx->lock); |
cdd6c482 | 4104 | if (event->attr.freq) { |
cdd6c482 | 4105 | event->attr.sample_freq = value; |
08247e31 | 4106 | } else { |
cdd6c482 IM |
4107 | event->attr.sample_period = value; |
4108 | event->hw.sample_period = value; | |
08247e31 | 4109 | } |
bad7192b PZ |
4110 | |
4111 | active = (event->state == PERF_EVENT_STATE_ACTIVE); | |
4112 | if (active) { | |
4113 | perf_pmu_disable(ctx->pmu); | |
4114 | event->pmu->stop(event, PERF_EF_UPDATE); | |
4115 | } | |
4116 | ||
4117 | local64_set(&event->hw.period_left, 0); | |
4118 | ||
4119 | if (active) { | |
4120 | event->pmu->start(event, PERF_EF_RELOAD); | |
4121 | perf_pmu_enable(ctx->pmu); | |
4122 | } | |
c7999c6f | 4123 | raw_spin_unlock(&ctx->lock); |
bad7192b | 4124 | |
c7999c6f PZ |
4125 | return 0; |
4126 | } | |
4127 | ||
4128 | static int perf_event_period(struct perf_event *event, u64 __user *arg) | |
4129 | { | |
4130 | struct period_event pe = { .event = event, }; | |
c7999c6f PZ |
4131 | u64 value; |
4132 | ||
4133 | if (!is_sampling_event(event)) | |
4134 | return -EINVAL; | |
4135 | ||
4136 | if (copy_from_user(&value, arg, sizeof(value))) | |
4137 | return -EFAULT; | |
4138 | ||
4139 | if (!value) | |
4140 | return -EINVAL; | |
4141 | ||
4142 | if (event->attr.freq && value > sysctl_perf_event_sample_rate) | |
4143 | return -EINVAL; | |
4144 | ||
c7999c6f PZ |
4145 | pe.value = value; |
4146 | ||
0017960f PZ |
4147 | event_function_call(event, __perf_event_period, |
4148 | ___perf_event_period, &pe); | |
08247e31 | 4149 | |
c7999c6f | 4150 | return 0; |
08247e31 PZ |
4151 | } |
4152 | ||
ac9721f3 PZ |
4153 | static const struct file_operations perf_fops; |
4154 | ||
2903ff01 | 4155 | static inline int perf_fget_light(int fd, struct fd *p) |
ac9721f3 | 4156 | { |
2903ff01 AV |
4157 | struct fd f = fdget(fd); |
4158 | if (!f.file) | |
4159 | return -EBADF; | |
ac9721f3 | 4160 | |
2903ff01 AV |
4161 | if (f.file->f_op != &perf_fops) { |
4162 | fdput(f); | |
4163 | return -EBADF; | |
ac9721f3 | 4164 | } |
2903ff01 AV |
4165 | *p = f; |
4166 | return 0; | |
ac9721f3 PZ |
4167 | } |
4168 | ||
4169 | static int perf_event_set_output(struct perf_event *event, | |
4170 | struct perf_event *output_event); | |
6fb2915d | 4171 | static int perf_event_set_filter(struct perf_event *event, void __user *arg); |
2541517c | 4172 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd); |
a4be7c27 | 4173 | |
f63a8daa | 4174 | static long _perf_ioctl(struct perf_event *event, unsigned int cmd, unsigned long arg) |
d859e29f | 4175 | { |
cdd6c482 | 4176 | void (*func)(struct perf_event *); |
3df5edad | 4177 | u32 flags = arg; |
d859e29f PM |
4178 | |
4179 | switch (cmd) { | |
cdd6c482 | 4180 | case PERF_EVENT_IOC_ENABLE: |
f63a8daa | 4181 | func = _perf_event_enable; |
d859e29f | 4182 | break; |
cdd6c482 | 4183 | case PERF_EVENT_IOC_DISABLE: |
f63a8daa | 4184 | func = _perf_event_disable; |
79f14641 | 4185 | break; |
cdd6c482 | 4186 | case PERF_EVENT_IOC_RESET: |
f63a8daa | 4187 | func = _perf_event_reset; |
6de6a7b9 | 4188 | break; |
3df5edad | 4189 | |
cdd6c482 | 4190 | case PERF_EVENT_IOC_REFRESH: |
f63a8daa | 4191 | return _perf_event_refresh(event, arg); |
08247e31 | 4192 | |
cdd6c482 IM |
4193 | case PERF_EVENT_IOC_PERIOD: |
4194 | return perf_event_period(event, (u64 __user *)arg); | |
08247e31 | 4195 | |
cf4957f1 JO |
4196 | case PERF_EVENT_IOC_ID: |
4197 | { | |
4198 | u64 id = primary_event_id(event); | |
4199 | ||
4200 | if (copy_to_user((void __user *)arg, &id, sizeof(id))) | |
4201 | return -EFAULT; | |
4202 | return 0; | |
4203 | } | |
4204 | ||
cdd6c482 | 4205 | case PERF_EVENT_IOC_SET_OUTPUT: |
ac9721f3 | 4206 | { |
ac9721f3 | 4207 | int ret; |
ac9721f3 | 4208 | if (arg != -1) { |
2903ff01 AV |
4209 | struct perf_event *output_event; |
4210 | struct fd output; | |
4211 | ret = perf_fget_light(arg, &output); | |
4212 | if (ret) | |
4213 | return ret; | |
4214 | output_event = output.file->private_data; | |
4215 | ret = perf_event_set_output(event, output_event); | |
4216 | fdput(output); | |
4217 | } else { | |
4218 | ret = perf_event_set_output(event, NULL); | |
ac9721f3 | 4219 | } |
ac9721f3 PZ |
4220 | return ret; |
4221 | } | |
a4be7c27 | 4222 | |
6fb2915d LZ |
4223 | case PERF_EVENT_IOC_SET_FILTER: |
4224 | return perf_event_set_filter(event, (void __user *)arg); | |
4225 | ||
2541517c AS |
4226 | case PERF_EVENT_IOC_SET_BPF: |
4227 | return perf_event_set_bpf_prog(event, arg); | |
4228 | ||
d859e29f | 4229 | default: |
3df5edad | 4230 | return -ENOTTY; |
d859e29f | 4231 | } |
3df5edad PZ |
4232 | |
4233 | if (flags & PERF_IOC_FLAG_GROUP) | |
cdd6c482 | 4234 | perf_event_for_each(event, func); |
3df5edad | 4235 | else |
cdd6c482 | 4236 | perf_event_for_each_child(event, func); |
3df5edad PZ |
4237 | |
4238 | return 0; | |
d859e29f PM |
4239 | } |
4240 | ||
f63a8daa PZ |
4241 | static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
4242 | { | |
4243 | struct perf_event *event = file->private_data; | |
4244 | struct perf_event_context *ctx; | |
4245 | long ret; | |
4246 | ||
4247 | ctx = perf_event_ctx_lock(event); | |
4248 | ret = _perf_ioctl(event, cmd, arg); | |
4249 | perf_event_ctx_unlock(event, ctx); | |
4250 | ||
4251 | return ret; | |
4252 | } | |
4253 | ||
b3f20785 PM |
4254 | #ifdef CONFIG_COMPAT |
4255 | static long perf_compat_ioctl(struct file *file, unsigned int cmd, | |
4256 | unsigned long arg) | |
4257 | { | |
4258 | switch (_IOC_NR(cmd)) { | |
4259 | case _IOC_NR(PERF_EVENT_IOC_SET_FILTER): | |
4260 | case _IOC_NR(PERF_EVENT_IOC_ID): | |
4261 | /* Fix up pointer size (usually 4 -> 8 in 32-on-64-bit case */ | |
4262 | if (_IOC_SIZE(cmd) == sizeof(compat_uptr_t)) { | |
4263 | cmd &= ~IOCSIZE_MASK; | |
4264 | cmd |= sizeof(void *) << IOCSIZE_SHIFT; | |
4265 | } | |
4266 | break; | |
4267 | } | |
4268 | return perf_ioctl(file, cmd, arg); | |
4269 | } | |
4270 | #else | |
4271 | # define perf_compat_ioctl NULL | |
4272 | #endif | |
4273 | ||
cdd6c482 | 4274 | int perf_event_task_enable(void) |
771d7cde | 4275 | { |
f63a8daa | 4276 | struct perf_event_context *ctx; |
cdd6c482 | 4277 | struct perf_event *event; |
771d7cde | 4278 | |
cdd6c482 | 4279 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
4280 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
4281 | ctx = perf_event_ctx_lock(event); | |
4282 | perf_event_for_each_child(event, _perf_event_enable); | |
4283 | perf_event_ctx_unlock(event, ctx); | |
4284 | } | |
cdd6c482 | 4285 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
4286 | |
4287 | return 0; | |
4288 | } | |
4289 | ||
cdd6c482 | 4290 | int perf_event_task_disable(void) |
771d7cde | 4291 | { |
f63a8daa | 4292 | struct perf_event_context *ctx; |
cdd6c482 | 4293 | struct perf_event *event; |
771d7cde | 4294 | |
cdd6c482 | 4295 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
4296 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
4297 | ctx = perf_event_ctx_lock(event); | |
4298 | perf_event_for_each_child(event, _perf_event_disable); | |
4299 | perf_event_ctx_unlock(event, ctx); | |
4300 | } | |
cdd6c482 | 4301 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
4302 | |
4303 | return 0; | |
4304 | } | |
4305 | ||
cdd6c482 | 4306 | static int perf_event_index(struct perf_event *event) |
194002b2 | 4307 | { |
a4eaf7f1 PZ |
4308 | if (event->hw.state & PERF_HES_STOPPED) |
4309 | return 0; | |
4310 | ||
cdd6c482 | 4311 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
194002b2 PZ |
4312 | return 0; |
4313 | ||
35edc2a5 | 4314 | return event->pmu->event_idx(event); |
194002b2 PZ |
4315 | } |
4316 | ||
c4794295 | 4317 | static void calc_timer_values(struct perf_event *event, |
e3f3541c | 4318 | u64 *now, |
7f310a5d EM |
4319 | u64 *enabled, |
4320 | u64 *running) | |
c4794295 | 4321 | { |
e3f3541c | 4322 | u64 ctx_time; |
c4794295 | 4323 | |
e3f3541c PZ |
4324 | *now = perf_clock(); |
4325 | ctx_time = event->shadow_ctx_time + *now; | |
c4794295 EM |
4326 | *enabled = ctx_time - event->tstamp_enabled; |
4327 | *running = ctx_time - event->tstamp_running; | |
4328 | } | |
4329 | ||
fa731587 PZ |
4330 | static void perf_event_init_userpage(struct perf_event *event) |
4331 | { | |
4332 | struct perf_event_mmap_page *userpg; | |
4333 | struct ring_buffer *rb; | |
4334 | ||
4335 | rcu_read_lock(); | |
4336 | rb = rcu_dereference(event->rb); | |
4337 | if (!rb) | |
4338 | goto unlock; | |
4339 | ||
4340 | userpg = rb->user_page; | |
4341 | ||
4342 | /* Allow new userspace to detect that bit 0 is deprecated */ | |
4343 | userpg->cap_bit0_is_deprecated = 1; | |
4344 | userpg->size = offsetof(struct perf_event_mmap_page, __reserved); | |
e8c6deac AS |
4345 | userpg->data_offset = PAGE_SIZE; |
4346 | userpg->data_size = perf_data_size(rb); | |
fa731587 PZ |
4347 | |
4348 | unlock: | |
4349 | rcu_read_unlock(); | |
4350 | } | |
4351 | ||
c1317ec2 AL |
4352 | void __weak arch_perf_update_userpage( |
4353 | struct perf_event *event, struct perf_event_mmap_page *userpg, u64 now) | |
e3f3541c PZ |
4354 | { |
4355 | } | |
4356 | ||
38ff667b PZ |
4357 | /* |
4358 | * Callers need to ensure there can be no nesting of this function, otherwise | |
4359 | * the seqlock logic goes bad. We can not serialize this because the arch | |
4360 | * code calls this from NMI context. | |
4361 | */ | |
cdd6c482 | 4362 | void perf_event_update_userpage(struct perf_event *event) |
37d81828 | 4363 | { |
cdd6c482 | 4364 | struct perf_event_mmap_page *userpg; |
76369139 | 4365 | struct ring_buffer *rb; |
e3f3541c | 4366 | u64 enabled, running, now; |
38ff667b PZ |
4367 | |
4368 | rcu_read_lock(); | |
5ec4c599 PZ |
4369 | rb = rcu_dereference(event->rb); |
4370 | if (!rb) | |
4371 | goto unlock; | |
4372 | ||
0d641208 EM |
4373 | /* |
4374 | * compute total_time_enabled, total_time_running | |
4375 | * based on snapshot values taken when the event | |
4376 | * was last scheduled in. | |
4377 | * | |
4378 | * we cannot simply called update_context_time() | |
4379 | * because of locking issue as we can be called in | |
4380 | * NMI context | |
4381 | */ | |
e3f3541c | 4382 | calc_timer_values(event, &now, &enabled, &running); |
38ff667b | 4383 | |
76369139 | 4384 | userpg = rb->user_page; |
7b732a75 PZ |
4385 | /* |
4386 | * Disable preemption so as to not let the corresponding user-space | |
4387 | * spin too long if we get preempted. | |
4388 | */ | |
4389 | preempt_disable(); | |
37d81828 | 4390 | ++userpg->lock; |
92f22a38 | 4391 | barrier(); |
cdd6c482 | 4392 | userpg->index = perf_event_index(event); |
b5e58793 | 4393 | userpg->offset = perf_event_count(event); |
365a4038 | 4394 | if (userpg->index) |
e7850595 | 4395 | userpg->offset -= local64_read(&event->hw.prev_count); |
7b732a75 | 4396 | |
0d641208 | 4397 | userpg->time_enabled = enabled + |
cdd6c482 | 4398 | atomic64_read(&event->child_total_time_enabled); |
7f8b4e4e | 4399 | |
0d641208 | 4400 | userpg->time_running = running + |
cdd6c482 | 4401 | atomic64_read(&event->child_total_time_running); |
7f8b4e4e | 4402 | |
c1317ec2 | 4403 | arch_perf_update_userpage(event, userpg, now); |
e3f3541c | 4404 | |
92f22a38 | 4405 | barrier(); |
37d81828 | 4406 | ++userpg->lock; |
7b732a75 | 4407 | preempt_enable(); |
38ff667b | 4408 | unlock: |
7b732a75 | 4409 | rcu_read_unlock(); |
37d81828 PM |
4410 | } |
4411 | ||
906010b2 PZ |
4412 | static int perf_mmap_fault(struct vm_area_struct *vma, struct vm_fault *vmf) |
4413 | { | |
4414 | struct perf_event *event = vma->vm_file->private_data; | |
76369139 | 4415 | struct ring_buffer *rb; |
906010b2 PZ |
4416 | int ret = VM_FAULT_SIGBUS; |
4417 | ||
4418 | if (vmf->flags & FAULT_FLAG_MKWRITE) { | |
4419 | if (vmf->pgoff == 0) | |
4420 | ret = 0; | |
4421 | return ret; | |
4422 | } | |
4423 | ||
4424 | rcu_read_lock(); | |
76369139 FW |
4425 | rb = rcu_dereference(event->rb); |
4426 | if (!rb) | |
906010b2 PZ |
4427 | goto unlock; |
4428 | ||
4429 | if (vmf->pgoff && (vmf->flags & FAULT_FLAG_WRITE)) | |
4430 | goto unlock; | |
4431 | ||
76369139 | 4432 | vmf->page = perf_mmap_to_page(rb, vmf->pgoff); |
906010b2 PZ |
4433 | if (!vmf->page) |
4434 | goto unlock; | |
4435 | ||
4436 | get_page(vmf->page); | |
4437 | vmf->page->mapping = vma->vm_file->f_mapping; | |
4438 | vmf->page->index = vmf->pgoff; | |
4439 | ||
4440 | ret = 0; | |
4441 | unlock: | |
4442 | rcu_read_unlock(); | |
4443 | ||
4444 | return ret; | |
4445 | } | |
4446 | ||
10c6db11 PZ |
4447 | static void ring_buffer_attach(struct perf_event *event, |
4448 | struct ring_buffer *rb) | |
4449 | { | |
b69cf536 | 4450 | struct ring_buffer *old_rb = NULL; |
10c6db11 PZ |
4451 | unsigned long flags; |
4452 | ||
b69cf536 PZ |
4453 | if (event->rb) { |
4454 | /* | |
4455 | * Should be impossible, we set this when removing | |
4456 | * event->rb_entry and wait/clear when adding event->rb_entry. | |
4457 | */ | |
4458 | WARN_ON_ONCE(event->rcu_pending); | |
10c6db11 | 4459 | |
b69cf536 | 4460 | old_rb = event->rb; |
b69cf536 PZ |
4461 | spin_lock_irqsave(&old_rb->event_lock, flags); |
4462 | list_del_rcu(&event->rb_entry); | |
4463 | spin_unlock_irqrestore(&old_rb->event_lock, flags); | |
10c6db11 | 4464 | |
2f993cf0 ON |
4465 | event->rcu_batches = get_state_synchronize_rcu(); |
4466 | event->rcu_pending = 1; | |
b69cf536 | 4467 | } |
10c6db11 | 4468 | |
b69cf536 | 4469 | if (rb) { |
2f993cf0 ON |
4470 | if (event->rcu_pending) { |
4471 | cond_synchronize_rcu(event->rcu_batches); | |
4472 | event->rcu_pending = 0; | |
4473 | } | |
4474 | ||
b69cf536 PZ |
4475 | spin_lock_irqsave(&rb->event_lock, flags); |
4476 | list_add_rcu(&event->rb_entry, &rb->event_list); | |
4477 | spin_unlock_irqrestore(&rb->event_lock, flags); | |
4478 | } | |
4479 | ||
4480 | rcu_assign_pointer(event->rb, rb); | |
4481 | ||
4482 | if (old_rb) { | |
4483 | ring_buffer_put(old_rb); | |
4484 | /* | |
4485 | * Since we detached before setting the new rb, so that we | |
4486 | * could attach the new rb, we could have missed a wakeup. | |
4487 | * Provide it now. | |
4488 | */ | |
4489 | wake_up_all(&event->waitq); | |
4490 | } | |
10c6db11 PZ |
4491 | } |
4492 | ||
4493 | static void ring_buffer_wakeup(struct perf_event *event) | |
4494 | { | |
4495 | struct ring_buffer *rb; | |
4496 | ||
4497 | rcu_read_lock(); | |
4498 | rb = rcu_dereference(event->rb); | |
9bb5d40c PZ |
4499 | if (rb) { |
4500 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) | |
4501 | wake_up_all(&event->waitq); | |
4502 | } | |
10c6db11 PZ |
4503 | rcu_read_unlock(); |
4504 | } | |
4505 | ||
fdc26706 | 4506 | struct ring_buffer *ring_buffer_get(struct perf_event *event) |
7b732a75 | 4507 | { |
76369139 | 4508 | struct ring_buffer *rb; |
7b732a75 | 4509 | |
ac9721f3 | 4510 | rcu_read_lock(); |
76369139 FW |
4511 | rb = rcu_dereference(event->rb); |
4512 | if (rb) { | |
4513 | if (!atomic_inc_not_zero(&rb->refcount)) | |
4514 | rb = NULL; | |
ac9721f3 PZ |
4515 | } |
4516 | rcu_read_unlock(); | |
4517 | ||
76369139 | 4518 | return rb; |
ac9721f3 PZ |
4519 | } |
4520 | ||
fdc26706 | 4521 | void ring_buffer_put(struct ring_buffer *rb) |
ac9721f3 | 4522 | { |
76369139 | 4523 | if (!atomic_dec_and_test(&rb->refcount)) |
ac9721f3 | 4524 | return; |
7b732a75 | 4525 | |
9bb5d40c | 4526 | WARN_ON_ONCE(!list_empty(&rb->event_list)); |
10c6db11 | 4527 | |
76369139 | 4528 | call_rcu(&rb->rcu_head, rb_free_rcu); |
7b732a75 PZ |
4529 | } |
4530 | ||
4531 | static void perf_mmap_open(struct vm_area_struct *vma) | |
4532 | { | |
cdd6c482 | 4533 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 4534 | |
cdd6c482 | 4535 | atomic_inc(&event->mmap_count); |
9bb5d40c | 4536 | atomic_inc(&event->rb->mmap_count); |
1e0fb9ec | 4537 | |
45bfb2e5 PZ |
4538 | if (vma->vm_pgoff) |
4539 | atomic_inc(&event->rb->aux_mmap_count); | |
4540 | ||
1e0fb9ec AL |
4541 | if (event->pmu->event_mapped) |
4542 | event->pmu->event_mapped(event); | |
7b732a75 PZ |
4543 | } |
4544 | ||
9bb5d40c PZ |
4545 | /* |
4546 | * A buffer can be mmap()ed multiple times; either directly through the same | |
4547 | * event, or through other events by use of perf_event_set_output(). | |
4548 | * | |
4549 | * In order to undo the VM accounting done by perf_mmap() we need to destroy | |
4550 | * the buffer here, where we still have a VM context. This means we need | |
4551 | * to detach all events redirecting to us. | |
4552 | */ | |
7b732a75 PZ |
4553 | static void perf_mmap_close(struct vm_area_struct *vma) |
4554 | { | |
cdd6c482 | 4555 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 4556 | |
b69cf536 | 4557 | struct ring_buffer *rb = ring_buffer_get(event); |
9bb5d40c PZ |
4558 | struct user_struct *mmap_user = rb->mmap_user; |
4559 | int mmap_locked = rb->mmap_locked; | |
4560 | unsigned long size = perf_data_size(rb); | |
789f90fc | 4561 | |
1e0fb9ec AL |
4562 | if (event->pmu->event_unmapped) |
4563 | event->pmu->event_unmapped(event); | |
4564 | ||
45bfb2e5 PZ |
4565 | /* |
4566 | * rb->aux_mmap_count will always drop before rb->mmap_count and | |
4567 | * event->mmap_count, so it is ok to use event->mmap_mutex to | |
4568 | * serialize with perf_mmap here. | |
4569 | */ | |
4570 | if (rb_has_aux(rb) && vma->vm_pgoff == rb->aux_pgoff && | |
4571 | atomic_dec_and_mutex_lock(&rb->aux_mmap_count, &event->mmap_mutex)) { | |
4572 | atomic_long_sub(rb->aux_nr_pages, &mmap_user->locked_vm); | |
4573 | vma->vm_mm->pinned_vm -= rb->aux_mmap_locked; | |
4574 | ||
4575 | rb_free_aux(rb); | |
4576 | mutex_unlock(&event->mmap_mutex); | |
4577 | } | |
4578 | ||
9bb5d40c PZ |
4579 | atomic_dec(&rb->mmap_count); |
4580 | ||
4581 | if (!atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex)) | |
b69cf536 | 4582 | goto out_put; |
9bb5d40c | 4583 | |
b69cf536 | 4584 | ring_buffer_attach(event, NULL); |
9bb5d40c PZ |
4585 | mutex_unlock(&event->mmap_mutex); |
4586 | ||
4587 | /* If there's still other mmap()s of this buffer, we're done. */ | |
b69cf536 PZ |
4588 | if (atomic_read(&rb->mmap_count)) |
4589 | goto out_put; | |
ac9721f3 | 4590 | |
9bb5d40c PZ |
4591 | /* |
4592 | * No other mmap()s, detach from all other events that might redirect | |
4593 | * into the now unreachable buffer. Somewhat complicated by the | |
4594 | * fact that rb::event_lock otherwise nests inside mmap_mutex. | |
4595 | */ | |
4596 | again: | |
4597 | rcu_read_lock(); | |
4598 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) { | |
4599 | if (!atomic_long_inc_not_zero(&event->refcount)) { | |
4600 | /* | |
4601 | * This event is en-route to free_event() which will | |
4602 | * detach it and remove it from the list. | |
4603 | */ | |
4604 | continue; | |
4605 | } | |
4606 | rcu_read_unlock(); | |
789f90fc | 4607 | |
9bb5d40c PZ |
4608 | mutex_lock(&event->mmap_mutex); |
4609 | /* | |
4610 | * Check we didn't race with perf_event_set_output() which can | |
4611 | * swizzle the rb from under us while we were waiting to | |
4612 | * acquire mmap_mutex. | |
4613 | * | |
4614 | * If we find a different rb; ignore this event, a next | |
4615 | * iteration will no longer find it on the list. We have to | |
4616 | * still restart the iteration to make sure we're not now | |
4617 | * iterating the wrong list. | |
4618 | */ | |
b69cf536 PZ |
4619 | if (event->rb == rb) |
4620 | ring_buffer_attach(event, NULL); | |
4621 | ||
cdd6c482 | 4622 | mutex_unlock(&event->mmap_mutex); |
9bb5d40c | 4623 | put_event(event); |
ac9721f3 | 4624 | |
9bb5d40c PZ |
4625 | /* |
4626 | * Restart the iteration; either we're on the wrong list or | |
4627 | * destroyed its integrity by doing a deletion. | |
4628 | */ | |
4629 | goto again; | |
7b732a75 | 4630 | } |
9bb5d40c PZ |
4631 | rcu_read_unlock(); |
4632 | ||
4633 | /* | |
4634 | * It could be there's still a few 0-ref events on the list; they'll | |
4635 | * get cleaned up by free_event() -- they'll also still have their | |
4636 | * ref on the rb and will free it whenever they are done with it. | |
4637 | * | |
4638 | * Aside from that, this buffer is 'fully' detached and unmapped, | |
4639 | * undo the VM accounting. | |
4640 | */ | |
4641 | ||
4642 | atomic_long_sub((size >> PAGE_SHIFT) + 1, &mmap_user->locked_vm); | |
4643 | vma->vm_mm->pinned_vm -= mmap_locked; | |
4644 | free_uid(mmap_user); | |
4645 | ||
b69cf536 | 4646 | out_put: |
9bb5d40c | 4647 | ring_buffer_put(rb); /* could be last */ |
37d81828 PM |
4648 | } |
4649 | ||
f0f37e2f | 4650 | static const struct vm_operations_struct perf_mmap_vmops = { |
43a21ea8 | 4651 | .open = perf_mmap_open, |
45bfb2e5 | 4652 | .close = perf_mmap_close, /* non mergable */ |
43a21ea8 PZ |
4653 | .fault = perf_mmap_fault, |
4654 | .page_mkwrite = perf_mmap_fault, | |
37d81828 PM |
4655 | }; |
4656 | ||
4657 | static int perf_mmap(struct file *file, struct vm_area_struct *vma) | |
4658 | { | |
cdd6c482 | 4659 | struct perf_event *event = file->private_data; |
22a4f650 | 4660 | unsigned long user_locked, user_lock_limit; |
789f90fc | 4661 | struct user_struct *user = current_user(); |
22a4f650 | 4662 | unsigned long locked, lock_limit; |
45bfb2e5 | 4663 | struct ring_buffer *rb = NULL; |
7b732a75 PZ |
4664 | unsigned long vma_size; |
4665 | unsigned long nr_pages; | |
45bfb2e5 | 4666 | long user_extra = 0, extra = 0; |
d57e34fd | 4667 | int ret = 0, flags = 0; |
37d81828 | 4668 | |
c7920614 PZ |
4669 | /* |
4670 | * Don't allow mmap() of inherited per-task counters. This would | |
4671 | * create a performance issue due to all children writing to the | |
76369139 | 4672 | * same rb. |
c7920614 PZ |
4673 | */ |
4674 | if (event->cpu == -1 && event->attr.inherit) | |
4675 | return -EINVAL; | |
4676 | ||
43a21ea8 | 4677 | if (!(vma->vm_flags & VM_SHARED)) |
37d81828 | 4678 | return -EINVAL; |
7b732a75 PZ |
4679 | |
4680 | vma_size = vma->vm_end - vma->vm_start; | |
45bfb2e5 PZ |
4681 | |
4682 | if (vma->vm_pgoff == 0) { | |
4683 | nr_pages = (vma_size / PAGE_SIZE) - 1; | |
4684 | } else { | |
4685 | /* | |
4686 | * AUX area mapping: if rb->aux_nr_pages != 0, it's already | |
4687 | * mapped, all subsequent mappings should have the same size | |
4688 | * and offset. Must be above the normal perf buffer. | |
4689 | */ | |
4690 | u64 aux_offset, aux_size; | |
4691 | ||
4692 | if (!event->rb) | |
4693 | return -EINVAL; | |
4694 | ||
4695 | nr_pages = vma_size / PAGE_SIZE; | |
4696 | ||
4697 | mutex_lock(&event->mmap_mutex); | |
4698 | ret = -EINVAL; | |
4699 | ||
4700 | rb = event->rb; | |
4701 | if (!rb) | |
4702 | goto aux_unlock; | |
4703 | ||
4704 | aux_offset = ACCESS_ONCE(rb->user_page->aux_offset); | |
4705 | aux_size = ACCESS_ONCE(rb->user_page->aux_size); | |
4706 | ||
4707 | if (aux_offset < perf_data_size(rb) + PAGE_SIZE) | |
4708 | goto aux_unlock; | |
4709 | ||
4710 | if (aux_offset != vma->vm_pgoff << PAGE_SHIFT) | |
4711 | goto aux_unlock; | |
4712 | ||
4713 | /* already mapped with a different offset */ | |
4714 | if (rb_has_aux(rb) && rb->aux_pgoff != vma->vm_pgoff) | |
4715 | goto aux_unlock; | |
4716 | ||
4717 | if (aux_size != vma_size || aux_size != nr_pages * PAGE_SIZE) | |
4718 | goto aux_unlock; | |
4719 | ||
4720 | /* already mapped with a different size */ | |
4721 | if (rb_has_aux(rb) && rb->aux_nr_pages != nr_pages) | |
4722 | goto aux_unlock; | |
4723 | ||
4724 | if (!is_power_of_2(nr_pages)) | |
4725 | goto aux_unlock; | |
4726 | ||
4727 | if (!atomic_inc_not_zero(&rb->mmap_count)) | |
4728 | goto aux_unlock; | |
4729 | ||
4730 | if (rb_has_aux(rb)) { | |
4731 | atomic_inc(&rb->aux_mmap_count); | |
4732 | ret = 0; | |
4733 | goto unlock; | |
4734 | } | |
4735 | ||
4736 | atomic_set(&rb->aux_mmap_count, 1); | |
4737 | user_extra = nr_pages; | |
4738 | ||
4739 | goto accounting; | |
4740 | } | |
7b732a75 | 4741 | |
7730d865 | 4742 | /* |
76369139 | 4743 | * If we have rb pages ensure they're a power-of-two number, so we |
7730d865 PZ |
4744 | * can do bitmasks instead of modulo. |
4745 | */ | |
2ed11312 | 4746 | if (nr_pages != 0 && !is_power_of_2(nr_pages)) |
37d81828 PM |
4747 | return -EINVAL; |
4748 | ||
7b732a75 | 4749 | if (vma_size != PAGE_SIZE * (1 + nr_pages)) |
37d81828 PM |
4750 | return -EINVAL; |
4751 | ||
cdd6c482 | 4752 | WARN_ON_ONCE(event->ctx->parent_ctx); |
9bb5d40c | 4753 | again: |
cdd6c482 | 4754 | mutex_lock(&event->mmap_mutex); |
76369139 | 4755 | if (event->rb) { |
9bb5d40c | 4756 | if (event->rb->nr_pages != nr_pages) { |
ebb3c4c4 | 4757 | ret = -EINVAL; |
9bb5d40c PZ |
4758 | goto unlock; |
4759 | } | |
4760 | ||
4761 | if (!atomic_inc_not_zero(&event->rb->mmap_count)) { | |
4762 | /* | |
4763 | * Raced against perf_mmap_close() through | |
4764 | * perf_event_set_output(). Try again, hope for better | |
4765 | * luck. | |
4766 | */ | |
4767 | mutex_unlock(&event->mmap_mutex); | |
4768 | goto again; | |
4769 | } | |
4770 | ||
ebb3c4c4 PZ |
4771 | goto unlock; |
4772 | } | |
4773 | ||
789f90fc | 4774 | user_extra = nr_pages + 1; |
45bfb2e5 PZ |
4775 | |
4776 | accounting: | |
cdd6c482 | 4777 | user_lock_limit = sysctl_perf_event_mlock >> (PAGE_SHIFT - 10); |
a3862d3f IM |
4778 | |
4779 | /* | |
4780 | * Increase the limit linearly with more CPUs: | |
4781 | */ | |
4782 | user_lock_limit *= num_online_cpus(); | |
4783 | ||
789f90fc | 4784 | user_locked = atomic_long_read(&user->locked_vm) + user_extra; |
c5078f78 | 4785 | |
789f90fc PZ |
4786 | if (user_locked > user_lock_limit) |
4787 | extra = user_locked - user_lock_limit; | |
7b732a75 | 4788 | |
78d7d407 | 4789 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
7b732a75 | 4790 | lock_limit >>= PAGE_SHIFT; |
bc3e53f6 | 4791 | locked = vma->vm_mm->pinned_vm + extra; |
7b732a75 | 4792 | |
459ec28a IM |
4793 | if ((locked > lock_limit) && perf_paranoid_tracepoint_raw() && |
4794 | !capable(CAP_IPC_LOCK)) { | |
ebb3c4c4 PZ |
4795 | ret = -EPERM; |
4796 | goto unlock; | |
4797 | } | |
7b732a75 | 4798 | |
45bfb2e5 | 4799 | WARN_ON(!rb && event->rb); |
906010b2 | 4800 | |
d57e34fd | 4801 | if (vma->vm_flags & VM_WRITE) |
76369139 | 4802 | flags |= RING_BUFFER_WRITABLE; |
d57e34fd | 4803 | |
76369139 | 4804 | if (!rb) { |
45bfb2e5 PZ |
4805 | rb = rb_alloc(nr_pages, |
4806 | event->attr.watermark ? event->attr.wakeup_watermark : 0, | |
4807 | event->cpu, flags); | |
26cb63ad | 4808 | |
45bfb2e5 PZ |
4809 | if (!rb) { |
4810 | ret = -ENOMEM; | |
4811 | goto unlock; | |
4812 | } | |
43a21ea8 | 4813 | |
45bfb2e5 PZ |
4814 | atomic_set(&rb->mmap_count, 1); |
4815 | rb->mmap_user = get_current_user(); | |
4816 | rb->mmap_locked = extra; | |
26cb63ad | 4817 | |
45bfb2e5 | 4818 | ring_buffer_attach(event, rb); |
ac9721f3 | 4819 | |
45bfb2e5 PZ |
4820 | perf_event_init_userpage(event); |
4821 | perf_event_update_userpage(event); | |
4822 | } else { | |
1a594131 AS |
4823 | ret = rb_alloc_aux(rb, event, vma->vm_pgoff, nr_pages, |
4824 | event->attr.aux_watermark, flags); | |
45bfb2e5 PZ |
4825 | if (!ret) |
4826 | rb->aux_mmap_locked = extra; | |
4827 | } | |
9a0f05cb | 4828 | |
ebb3c4c4 | 4829 | unlock: |
45bfb2e5 PZ |
4830 | if (!ret) { |
4831 | atomic_long_add(user_extra, &user->locked_vm); | |
4832 | vma->vm_mm->pinned_vm += extra; | |
4833 | ||
ac9721f3 | 4834 | atomic_inc(&event->mmap_count); |
45bfb2e5 PZ |
4835 | } else if (rb) { |
4836 | atomic_dec(&rb->mmap_count); | |
4837 | } | |
4838 | aux_unlock: | |
cdd6c482 | 4839 | mutex_unlock(&event->mmap_mutex); |
37d81828 | 4840 | |
9bb5d40c PZ |
4841 | /* |
4842 | * Since pinned accounting is per vm we cannot allow fork() to copy our | |
4843 | * vma. | |
4844 | */ | |
26cb63ad | 4845 | vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND | VM_DONTDUMP; |
37d81828 | 4846 | vma->vm_ops = &perf_mmap_vmops; |
7b732a75 | 4847 | |
1e0fb9ec AL |
4848 | if (event->pmu->event_mapped) |
4849 | event->pmu->event_mapped(event); | |
4850 | ||
7b732a75 | 4851 | return ret; |
37d81828 PM |
4852 | } |
4853 | ||
3c446b3d PZ |
4854 | static int perf_fasync(int fd, struct file *filp, int on) |
4855 | { | |
496ad9aa | 4856 | struct inode *inode = file_inode(filp); |
cdd6c482 | 4857 | struct perf_event *event = filp->private_data; |
3c446b3d PZ |
4858 | int retval; |
4859 | ||
4860 | mutex_lock(&inode->i_mutex); | |
cdd6c482 | 4861 | retval = fasync_helper(fd, filp, on, &event->fasync); |
3c446b3d PZ |
4862 | mutex_unlock(&inode->i_mutex); |
4863 | ||
4864 | if (retval < 0) | |
4865 | return retval; | |
4866 | ||
4867 | return 0; | |
4868 | } | |
4869 | ||
0793a61d | 4870 | static const struct file_operations perf_fops = { |
3326c1ce | 4871 | .llseek = no_llseek, |
0793a61d TG |
4872 | .release = perf_release, |
4873 | .read = perf_read, | |
4874 | .poll = perf_poll, | |
d859e29f | 4875 | .unlocked_ioctl = perf_ioctl, |
b3f20785 | 4876 | .compat_ioctl = perf_compat_ioctl, |
37d81828 | 4877 | .mmap = perf_mmap, |
3c446b3d | 4878 | .fasync = perf_fasync, |
0793a61d TG |
4879 | }; |
4880 | ||
925d519a | 4881 | /* |
cdd6c482 | 4882 | * Perf event wakeup |
925d519a PZ |
4883 | * |
4884 | * If there's data, ensure we set the poll() state and publish everything | |
4885 | * to user-space before waking everybody up. | |
4886 | */ | |
4887 | ||
fed66e2c PZ |
4888 | static inline struct fasync_struct **perf_event_fasync(struct perf_event *event) |
4889 | { | |
4890 | /* only the parent has fasync state */ | |
4891 | if (event->parent) | |
4892 | event = event->parent; | |
4893 | return &event->fasync; | |
4894 | } | |
4895 | ||
cdd6c482 | 4896 | void perf_event_wakeup(struct perf_event *event) |
925d519a | 4897 | { |
10c6db11 | 4898 | ring_buffer_wakeup(event); |
4c9e2542 | 4899 | |
cdd6c482 | 4900 | if (event->pending_kill) { |
fed66e2c | 4901 | kill_fasync(perf_event_fasync(event), SIGIO, event->pending_kill); |
cdd6c482 | 4902 | event->pending_kill = 0; |
4c9e2542 | 4903 | } |
925d519a PZ |
4904 | } |
4905 | ||
e360adbe | 4906 | static void perf_pending_event(struct irq_work *entry) |
79f14641 | 4907 | { |
cdd6c482 IM |
4908 | struct perf_event *event = container_of(entry, |
4909 | struct perf_event, pending); | |
d525211f PZ |
4910 | int rctx; |
4911 | ||
4912 | rctx = perf_swevent_get_recursion_context(); | |
4913 | /* | |
4914 | * If we 'fail' here, that's OK, it means recursion is already disabled | |
4915 | * and we won't recurse 'further'. | |
4916 | */ | |
79f14641 | 4917 | |
cdd6c482 IM |
4918 | if (event->pending_disable) { |
4919 | event->pending_disable = 0; | |
4920 | __perf_event_disable(event); | |
79f14641 PZ |
4921 | } |
4922 | ||
cdd6c482 IM |
4923 | if (event->pending_wakeup) { |
4924 | event->pending_wakeup = 0; | |
4925 | perf_event_wakeup(event); | |
79f14641 | 4926 | } |
d525211f PZ |
4927 | |
4928 | if (rctx >= 0) | |
4929 | perf_swevent_put_recursion_context(rctx); | |
79f14641 PZ |
4930 | } |
4931 | ||
39447b38 ZY |
4932 | /* |
4933 | * We assume there is only KVM supporting the callbacks. | |
4934 | * Later on, we might change it to a list if there is | |
4935 | * another virtualization implementation supporting the callbacks. | |
4936 | */ | |
4937 | struct perf_guest_info_callbacks *perf_guest_cbs; | |
4938 | ||
4939 | int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
4940 | { | |
4941 | perf_guest_cbs = cbs; | |
4942 | return 0; | |
4943 | } | |
4944 | EXPORT_SYMBOL_GPL(perf_register_guest_info_callbacks); | |
4945 | ||
4946 | int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
4947 | { | |
4948 | perf_guest_cbs = NULL; | |
4949 | return 0; | |
4950 | } | |
4951 | EXPORT_SYMBOL_GPL(perf_unregister_guest_info_callbacks); | |
4952 | ||
4018994f JO |
4953 | static void |
4954 | perf_output_sample_regs(struct perf_output_handle *handle, | |
4955 | struct pt_regs *regs, u64 mask) | |
4956 | { | |
4957 | int bit; | |
4958 | ||
4959 | for_each_set_bit(bit, (const unsigned long *) &mask, | |
4960 | sizeof(mask) * BITS_PER_BYTE) { | |
4961 | u64 val; | |
4962 | ||
4963 | val = perf_reg_value(regs, bit); | |
4964 | perf_output_put(handle, val); | |
4965 | } | |
4966 | } | |
4967 | ||
60e2364e | 4968 | static void perf_sample_regs_user(struct perf_regs *regs_user, |
88a7c26a AL |
4969 | struct pt_regs *regs, |
4970 | struct pt_regs *regs_user_copy) | |
4018994f | 4971 | { |
88a7c26a AL |
4972 | if (user_mode(regs)) { |
4973 | regs_user->abi = perf_reg_abi(current); | |
2565711f | 4974 | regs_user->regs = regs; |
88a7c26a AL |
4975 | } else if (current->mm) { |
4976 | perf_get_regs_user(regs_user, regs, regs_user_copy); | |
2565711f PZ |
4977 | } else { |
4978 | regs_user->abi = PERF_SAMPLE_REGS_ABI_NONE; | |
4979 | regs_user->regs = NULL; | |
4018994f JO |
4980 | } |
4981 | } | |
4982 | ||
60e2364e SE |
4983 | static void perf_sample_regs_intr(struct perf_regs *regs_intr, |
4984 | struct pt_regs *regs) | |
4985 | { | |
4986 | regs_intr->regs = regs; | |
4987 | regs_intr->abi = perf_reg_abi(current); | |
4988 | } | |
4989 | ||
4990 | ||
c5ebcedb JO |
4991 | /* |
4992 | * Get remaining task size from user stack pointer. | |
4993 | * | |
4994 | * It'd be better to take stack vma map and limit this more | |
4995 | * precisly, but there's no way to get it safely under interrupt, | |
4996 | * so using TASK_SIZE as limit. | |
4997 | */ | |
4998 | static u64 perf_ustack_task_size(struct pt_regs *regs) | |
4999 | { | |
5000 | unsigned long addr = perf_user_stack_pointer(regs); | |
5001 | ||
5002 | if (!addr || addr >= TASK_SIZE) | |
5003 | return 0; | |
5004 | ||
5005 | return TASK_SIZE - addr; | |
5006 | } | |
5007 | ||
5008 | static u16 | |
5009 | perf_sample_ustack_size(u16 stack_size, u16 header_size, | |
5010 | struct pt_regs *regs) | |
5011 | { | |
5012 | u64 task_size; | |
5013 | ||
5014 | /* No regs, no stack pointer, no dump. */ | |
5015 | if (!regs) | |
5016 | return 0; | |
5017 | ||
5018 | /* | |
5019 | * Check if we fit in with the requested stack size into the: | |
5020 | * - TASK_SIZE | |
5021 | * If we don't, we limit the size to the TASK_SIZE. | |
5022 | * | |
5023 | * - remaining sample size | |
5024 | * If we don't, we customize the stack size to | |
5025 | * fit in to the remaining sample size. | |
5026 | */ | |
5027 | ||
5028 | task_size = min((u64) USHRT_MAX, perf_ustack_task_size(regs)); | |
5029 | stack_size = min(stack_size, (u16) task_size); | |
5030 | ||
5031 | /* Current header size plus static size and dynamic size. */ | |
5032 | header_size += 2 * sizeof(u64); | |
5033 | ||
5034 | /* Do we fit in with the current stack dump size? */ | |
5035 | if ((u16) (header_size + stack_size) < header_size) { | |
5036 | /* | |
5037 | * If we overflow the maximum size for the sample, | |
5038 | * we customize the stack dump size to fit in. | |
5039 | */ | |
5040 | stack_size = USHRT_MAX - header_size - sizeof(u64); | |
5041 | stack_size = round_up(stack_size, sizeof(u64)); | |
5042 | } | |
5043 | ||
5044 | return stack_size; | |
5045 | } | |
5046 | ||
5047 | static void | |
5048 | perf_output_sample_ustack(struct perf_output_handle *handle, u64 dump_size, | |
5049 | struct pt_regs *regs) | |
5050 | { | |
5051 | /* Case of a kernel thread, nothing to dump */ | |
5052 | if (!regs) { | |
5053 | u64 size = 0; | |
5054 | perf_output_put(handle, size); | |
5055 | } else { | |
5056 | unsigned long sp; | |
5057 | unsigned int rem; | |
5058 | u64 dyn_size; | |
5059 | ||
5060 | /* | |
5061 | * We dump: | |
5062 | * static size | |
5063 | * - the size requested by user or the best one we can fit | |
5064 | * in to the sample max size | |
5065 | * data | |
5066 | * - user stack dump data | |
5067 | * dynamic size | |
5068 | * - the actual dumped size | |
5069 | */ | |
5070 | ||
5071 | /* Static size. */ | |
5072 | perf_output_put(handle, dump_size); | |
5073 | ||
5074 | /* Data. */ | |
5075 | sp = perf_user_stack_pointer(regs); | |
5076 | rem = __output_copy_user(handle, (void *) sp, dump_size); | |
5077 | dyn_size = dump_size - rem; | |
5078 | ||
5079 | perf_output_skip(handle, rem); | |
5080 | ||
5081 | /* Dynamic size. */ | |
5082 | perf_output_put(handle, dyn_size); | |
5083 | } | |
5084 | } | |
5085 | ||
c980d109 ACM |
5086 | static void __perf_event_header__init_id(struct perf_event_header *header, |
5087 | struct perf_sample_data *data, | |
5088 | struct perf_event *event) | |
6844c09d ACM |
5089 | { |
5090 | u64 sample_type = event->attr.sample_type; | |
5091 | ||
5092 | data->type = sample_type; | |
5093 | header->size += event->id_header_size; | |
5094 | ||
5095 | if (sample_type & PERF_SAMPLE_TID) { | |
5096 | /* namespace issues */ | |
5097 | data->tid_entry.pid = perf_event_pid(event, current); | |
5098 | data->tid_entry.tid = perf_event_tid(event, current); | |
5099 | } | |
5100 | ||
5101 | if (sample_type & PERF_SAMPLE_TIME) | |
34f43927 | 5102 | data->time = perf_event_clock(event); |
6844c09d | 5103 | |
ff3d527c | 5104 | if (sample_type & (PERF_SAMPLE_ID | PERF_SAMPLE_IDENTIFIER)) |
6844c09d ACM |
5105 | data->id = primary_event_id(event); |
5106 | ||
5107 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
5108 | data->stream_id = event->id; | |
5109 | ||
5110 | if (sample_type & PERF_SAMPLE_CPU) { | |
5111 | data->cpu_entry.cpu = raw_smp_processor_id(); | |
5112 | data->cpu_entry.reserved = 0; | |
5113 | } | |
5114 | } | |
5115 | ||
76369139 FW |
5116 | void perf_event_header__init_id(struct perf_event_header *header, |
5117 | struct perf_sample_data *data, | |
5118 | struct perf_event *event) | |
c980d109 ACM |
5119 | { |
5120 | if (event->attr.sample_id_all) | |
5121 | __perf_event_header__init_id(header, data, event); | |
5122 | } | |
5123 | ||
5124 | static void __perf_event__output_id_sample(struct perf_output_handle *handle, | |
5125 | struct perf_sample_data *data) | |
5126 | { | |
5127 | u64 sample_type = data->type; | |
5128 | ||
5129 | if (sample_type & PERF_SAMPLE_TID) | |
5130 | perf_output_put(handle, data->tid_entry); | |
5131 | ||
5132 | if (sample_type & PERF_SAMPLE_TIME) | |
5133 | perf_output_put(handle, data->time); | |
5134 | ||
5135 | if (sample_type & PERF_SAMPLE_ID) | |
5136 | perf_output_put(handle, data->id); | |
5137 | ||
5138 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
5139 | perf_output_put(handle, data->stream_id); | |
5140 | ||
5141 | if (sample_type & PERF_SAMPLE_CPU) | |
5142 | perf_output_put(handle, data->cpu_entry); | |
ff3d527c AH |
5143 | |
5144 | if (sample_type & PERF_SAMPLE_IDENTIFIER) | |
5145 | perf_output_put(handle, data->id); | |
c980d109 ACM |
5146 | } |
5147 | ||
76369139 FW |
5148 | void perf_event__output_id_sample(struct perf_event *event, |
5149 | struct perf_output_handle *handle, | |
5150 | struct perf_sample_data *sample) | |
c980d109 ACM |
5151 | { |
5152 | if (event->attr.sample_id_all) | |
5153 | __perf_event__output_id_sample(handle, sample); | |
5154 | } | |
5155 | ||
3dab77fb | 5156 | static void perf_output_read_one(struct perf_output_handle *handle, |
eed01528 SE |
5157 | struct perf_event *event, |
5158 | u64 enabled, u64 running) | |
3dab77fb | 5159 | { |
cdd6c482 | 5160 | u64 read_format = event->attr.read_format; |
3dab77fb PZ |
5161 | u64 values[4]; |
5162 | int n = 0; | |
5163 | ||
b5e58793 | 5164 | values[n++] = perf_event_count(event); |
3dab77fb | 5165 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { |
eed01528 | 5166 | values[n++] = enabled + |
cdd6c482 | 5167 | atomic64_read(&event->child_total_time_enabled); |
3dab77fb PZ |
5168 | } |
5169 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { | |
eed01528 | 5170 | values[n++] = running + |
cdd6c482 | 5171 | atomic64_read(&event->child_total_time_running); |
3dab77fb PZ |
5172 | } |
5173 | if (read_format & PERF_FORMAT_ID) | |
cdd6c482 | 5174 | values[n++] = primary_event_id(event); |
3dab77fb | 5175 | |
76369139 | 5176 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
5177 | } |
5178 | ||
5179 | /* | |
cdd6c482 | 5180 | * XXX PERF_FORMAT_GROUP vs inherited events seems difficult. |
3dab77fb PZ |
5181 | */ |
5182 | static void perf_output_read_group(struct perf_output_handle *handle, | |
eed01528 SE |
5183 | struct perf_event *event, |
5184 | u64 enabled, u64 running) | |
3dab77fb | 5185 | { |
cdd6c482 IM |
5186 | struct perf_event *leader = event->group_leader, *sub; |
5187 | u64 read_format = event->attr.read_format; | |
3dab77fb PZ |
5188 | u64 values[5]; |
5189 | int n = 0; | |
5190 | ||
5191 | values[n++] = 1 + leader->nr_siblings; | |
5192 | ||
5193 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
eed01528 | 5194 | values[n++] = enabled; |
3dab77fb PZ |
5195 | |
5196 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
eed01528 | 5197 | values[n++] = running; |
3dab77fb | 5198 | |
cdd6c482 | 5199 | if (leader != event) |
3dab77fb PZ |
5200 | leader->pmu->read(leader); |
5201 | ||
b5e58793 | 5202 | values[n++] = perf_event_count(leader); |
3dab77fb | 5203 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 5204 | values[n++] = primary_event_id(leader); |
3dab77fb | 5205 | |
76369139 | 5206 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb | 5207 | |
65abc865 | 5208 | list_for_each_entry(sub, &leader->sibling_list, group_entry) { |
3dab77fb PZ |
5209 | n = 0; |
5210 | ||
6f5ab001 JO |
5211 | if ((sub != event) && |
5212 | (sub->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
5213 | sub->pmu->read(sub); |
5214 | ||
b5e58793 | 5215 | values[n++] = perf_event_count(sub); |
3dab77fb | 5216 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 5217 | values[n++] = primary_event_id(sub); |
3dab77fb | 5218 | |
76369139 | 5219 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
5220 | } |
5221 | } | |
5222 | ||
eed01528 SE |
5223 | #define PERF_FORMAT_TOTAL_TIMES (PERF_FORMAT_TOTAL_TIME_ENABLED|\ |
5224 | PERF_FORMAT_TOTAL_TIME_RUNNING) | |
5225 | ||
3dab77fb | 5226 | static void perf_output_read(struct perf_output_handle *handle, |
cdd6c482 | 5227 | struct perf_event *event) |
3dab77fb | 5228 | { |
e3f3541c | 5229 | u64 enabled = 0, running = 0, now; |
eed01528 SE |
5230 | u64 read_format = event->attr.read_format; |
5231 | ||
5232 | /* | |
5233 | * compute total_time_enabled, total_time_running | |
5234 | * based on snapshot values taken when the event | |
5235 | * was last scheduled in. | |
5236 | * | |
5237 | * we cannot simply called update_context_time() | |
5238 | * because of locking issue as we are called in | |
5239 | * NMI context | |
5240 | */ | |
c4794295 | 5241 | if (read_format & PERF_FORMAT_TOTAL_TIMES) |
e3f3541c | 5242 | calc_timer_values(event, &now, &enabled, &running); |
eed01528 | 5243 | |
cdd6c482 | 5244 | if (event->attr.read_format & PERF_FORMAT_GROUP) |
eed01528 | 5245 | perf_output_read_group(handle, event, enabled, running); |
3dab77fb | 5246 | else |
eed01528 | 5247 | perf_output_read_one(handle, event, enabled, running); |
3dab77fb PZ |
5248 | } |
5249 | ||
5622f295 MM |
5250 | void perf_output_sample(struct perf_output_handle *handle, |
5251 | struct perf_event_header *header, | |
5252 | struct perf_sample_data *data, | |
cdd6c482 | 5253 | struct perf_event *event) |
5622f295 MM |
5254 | { |
5255 | u64 sample_type = data->type; | |
5256 | ||
5257 | perf_output_put(handle, *header); | |
5258 | ||
ff3d527c AH |
5259 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
5260 | perf_output_put(handle, data->id); | |
5261 | ||
5622f295 MM |
5262 | if (sample_type & PERF_SAMPLE_IP) |
5263 | perf_output_put(handle, data->ip); | |
5264 | ||
5265 | if (sample_type & PERF_SAMPLE_TID) | |
5266 | perf_output_put(handle, data->tid_entry); | |
5267 | ||
5268 | if (sample_type & PERF_SAMPLE_TIME) | |
5269 | perf_output_put(handle, data->time); | |
5270 | ||
5271 | if (sample_type & PERF_SAMPLE_ADDR) | |
5272 | perf_output_put(handle, data->addr); | |
5273 | ||
5274 | if (sample_type & PERF_SAMPLE_ID) | |
5275 | perf_output_put(handle, data->id); | |
5276 | ||
5277 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
5278 | perf_output_put(handle, data->stream_id); | |
5279 | ||
5280 | if (sample_type & PERF_SAMPLE_CPU) | |
5281 | perf_output_put(handle, data->cpu_entry); | |
5282 | ||
5283 | if (sample_type & PERF_SAMPLE_PERIOD) | |
5284 | perf_output_put(handle, data->period); | |
5285 | ||
5286 | if (sample_type & PERF_SAMPLE_READ) | |
cdd6c482 | 5287 | perf_output_read(handle, event); |
5622f295 MM |
5288 | |
5289 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { | |
5290 | if (data->callchain) { | |
5291 | int size = 1; | |
5292 | ||
5293 | if (data->callchain) | |
5294 | size += data->callchain->nr; | |
5295 | ||
5296 | size *= sizeof(u64); | |
5297 | ||
76369139 | 5298 | __output_copy(handle, data->callchain, size); |
5622f295 MM |
5299 | } else { |
5300 | u64 nr = 0; | |
5301 | perf_output_put(handle, nr); | |
5302 | } | |
5303 | } | |
5304 | ||
5305 | if (sample_type & PERF_SAMPLE_RAW) { | |
5306 | if (data->raw) { | |
fa128e6a AS |
5307 | u32 raw_size = data->raw->size; |
5308 | u32 real_size = round_up(raw_size + sizeof(u32), | |
5309 | sizeof(u64)) - sizeof(u32); | |
5310 | u64 zero = 0; | |
5311 | ||
5312 | perf_output_put(handle, real_size); | |
5313 | __output_copy(handle, data->raw->data, raw_size); | |
5314 | if (real_size - raw_size) | |
5315 | __output_copy(handle, &zero, real_size - raw_size); | |
5622f295 MM |
5316 | } else { |
5317 | struct { | |
5318 | u32 size; | |
5319 | u32 data; | |
5320 | } raw = { | |
5321 | .size = sizeof(u32), | |
5322 | .data = 0, | |
5323 | }; | |
5324 | perf_output_put(handle, raw); | |
5325 | } | |
5326 | } | |
a7ac67ea | 5327 | |
bce38cd5 SE |
5328 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { |
5329 | if (data->br_stack) { | |
5330 | size_t size; | |
5331 | ||
5332 | size = data->br_stack->nr | |
5333 | * sizeof(struct perf_branch_entry); | |
5334 | ||
5335 | perf_output_put(handle, data->br_stack->nr); | |
5336 | perf_output_copy(handle, data->br_stack->entries, size); | |
5337 | } else { | |
5338 | /* | |
5339 | * we always store at least the value of nr | |
5340 | */ | |
5341 | u64 nr = 0; | |
5342 | perf_output_put(handle, nr); | |
5343 | } | |
5344 | } | |
4018994f JO |
5345 | |
5346 | if (sample_type & PERF_SAMPLE_REGS_USER) { | |
5347 | u64 abi = data->regs_user.abi; | |
5348 | ||
5349 | /* | |
5350 | * If there are no regs to dump, notice it through | |
5351 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
5352 | */ | |
5353 | perf_output_put(handle, abi); | |
5354 | ||
5355 | if (abi) { | |
5356 | u64 mask = event->attr.sample_regs_user; | |
5357 | perf_output_sample_regs(handle, | |
5358 | data->regs_user.regs, | |
5359 | mask); | |
5360 | } | |
5361 | } | |
c5ebcedb | 5362 | |
a5cdd40c | 5363 | if (sample_type & PERF_SAMPLE_STACK_USER) { |
c5ebcedb JO |
5364 | perf_output_sample_ustack(handle, |
5365 | data->stack_user_size, | |
5366 | data->regs_user.regs); | |
a5cdd40c | 5367 | } |
c3feedf2 AK |
5368 | |
5369 | if (sample_type & PERF_SAMPLE_WEIGHT) | |
5370 | perf_output_put(handle, data->weight); | |
d6be9ad6 SE |
5371 | |
5372 | if (sample_type & PERF_SAMPLE_DATA_SRC) | |
5373 | perf_output_put(handle, data->data_src.val); | |
a5cdd40c | 5374 | |
fdfbbd07 AK |
5375 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
5376 | perf_output_put(handle, data->txn); | |
5377 | ||
60e2364e SE |
5378 | if (sample_type & PERF_SAMPLE_REGS_INTR) { |
5379 | u64 abi = data->regs_intr.abi; | |
5380 | /* | |
5381 | * If there are no regs to dump, notice it through | |
5382 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
5383 | */ | |
5384 | perf_output_put(handle, abi); | |
5385 | ||
5386 | if (abi) { | |
5387 | u64 mask = event->attr.sample_regs_intr; | |
5388 | ||
5389 | perf_output_sample_regs(handle, | |
5390 | data->regs_intr.regs, | |
5391 | mask); | |
5392 | } | |
5393 | } | |
5394 | ||
a5cdd40c PZ |
5395 | if (!event->attr.watermark) { |
5396 | int wakeup_events = event->attr.wakeup_events; | |
5397 | ||
5398 | if (wakeup_events) { | |
5399 | struct ring_buffer *rb = handle->rb; | |
5400 | int events = local_inc_return(&rb->events); | |
5401 | ||
5402 | if (events >= wakeup_events) { | |
5403 | local_sub(wakeup_events, &rb->events); | |
5404 | local_inc(&rb->wakeup); | |
5405 | } | |
5406 | } | |
5407 | } | |
5622f295 MM |
5408 | } |
5409 | ||
5410 | void perf_prepare_sample(struct perf_event_header *header, | |
5411 | struct perf_sample_data *data, | |
cdd6c482 | 5412 | struct perf_event *event, |
5622f295 | 5413 | struct pt_regs *regs) |
7b732a75 | 5414 | { |
cdd6c482 | 5415 | u64 sample_type = event->attr.sample_type; |
7b732a75 | 5416 | |
cdd6c482 | 5417 | header->type = PERF_RECORD_SAMPLE; |
c320c7b7 | 5418 | header->size = sizeof(*header) + event->header_size; |
5622f295 MM |
5419 | |
5420 | header->misc = 0; | |
5421 | header->misc |= perf_misc_flags(regs); | |
6fab0192 | 5422 | |
c980d109 | 5423 | __perf_event_header__init_id(header, data, event); |
6844c09d | 5424 | |
c320c7b7 | 5425 | if (sample_type & PERF_SAMPLE_IP) |
5622f295 MM |
5426 | data->ip = perf_instruction_pointer(regs); |
5427 | ||
b23f3325 | 5428 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { |
5622f295 | 5429 | int size = 1; |
394ee076 | 5430 | |
e6dab5ff | 5431 | data->callchain = perf_callchain(event, regs); |
5622f295 MM |
5432 | |
5433 | if (data->callchain) | |
5434 | size += data->callchain->nr; | |
5435 | ||
5436 | header->size += size * sizeof(u64); | |
394ee076 PZ |
5437 | } |
5438 | ||
3a43ce68 | 5439 | if (sample_type & PERF_SAMPLE_RAW) { |
a044560c PZ |
5440 | int size = sizeof(u32); |
5441 | ||
5442 | if (data->raw) | |
5443 | size += data->raw->size; | |
5444 | else | |
5445 | size += sizeof(u32); | |
5446 | ||
fa128e6a | 5447 | header->size += round_up(size, sizeof(u64)); |
7f453c24 | 5448 | } |
bce38cd5 SE |
5449 | |
5450 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { | |
5451 | int size = sizeof(u64); /* nr */ | |
5452 | if (data->br_stack) { | |
5453 | size += data->br_stack->nr | |
5454 | * sizeof(struct perf_branch_entry); | |
5455 | } | |
5456 | header->size += size; | |
5457 | } | |
4018994f | 5458 | |
2565711f | 5459 | if (sample_type & (PERF_SAMPLE_REGS_USER | PERF_SAMPLE_STACK_USER)) |
88a7c26a AL |
5460 | perf_sample_regs_user(&data->regs_user, regs, |
5461 | &data->regs_user_copy); | |
2565711f | 5462 | |
4018994f JO |
5463 | if (sample_type & PERF_SAMPLE_REGS_USER) { |
5464 | /* regs dump ABI info */ | |
5465 | int size = sizeof(u64); | |
5466 | ||
4018994f JO |
5467 | if (data->regs_user.regs) { |
5468 | u64 mask = event->attr.sample_regs_user; | |
5469 | size += hweight64(mask) * sizeof(u64); | |
5470 | } | |
5471 | ||
5472 | header->size += size; | |
5473 | } | |
c5ebcedb JO |
5474 | |
5475 | if (sample_type & PERF_SAMPLE_STACK_USER) { | |
5476 | /* | |
5477 | * Either we need PERF_SAMPLE_STACK_USER bit to be allways | |
5478 | * processed as the last one or have additional check added | |
5479 | * in case new sample type is added, because we could eat | |
5480 | * up the rest of the sample size. | |
5481 | */ | |
c5ebcedb JO |
5482 | u16 stack_size = event->attr.sample_stack_user; |
5483 | u16 size = sizeof(u64); | |
5484 | ||
c5ebcedb | 5485 | stack_size = perf_sample_ustack_size(stack_size, header->size, |
2565711f | 5486 | data->regs_user.regs); |
c5ebcedb JO |
5487 | |
5488 | /* | |
5489 | * If there is something to dump, add space for the dump | |
5490 | * itself and for the field that tells the dynamic size, | |
5491 | * which is how many have been actually dumped. | |
5492 | */ | |
5493 | if (stack_size) | |
5494 | size += sizeof(u64) + stack_size; | |
5495 | ||
5496 | data->stack_user_size = stack_size; | |
5497 | header->size += size; | |
5498 | } | |
60e2364e SE |
5499 | |
5500 | if (sample_type & PERF_SAMPLE_REGS_INTR) { | |
5501 | /* regs dump ABI info */ | |
5502 | int size = sizeof(u64); | |
5503 | ||
5504 | perf_sample_regs_intr(&data->regs_intr, regs); | |
5505 | ||
5506 | if (data->regs_intr.regs) { | |
5507 | u64 mask = event->attr.sample_regs_intr; | |
5508 | ||
5509 | size += hweight64(mask) * sizeof(u64); | |
5510 | } | |
5511 | ||
5512 | header->size += size; | |
5513 | } | |
5622f295 | 5514 | } |
7f453c24 | 5515 | |
21509084 YZ |
5516 | void perf_event_output(struct perf_event *event, |
5517 | struct perf_sample_data *data, | |
5518 | struct pt_regs *regs) | |
5622f295 MM |
5519 | { |
5520 | struct perf_output_handle handle; | |
5521 | struct perf_event_header header; | |
689802b2 | 5522 | |
927c7a9e FW |
5523 | /* protect the callchain buffers */ |
5524 | rcu_read_lock(); | |
5525 | ||
cdd6c482 | 5526 | perf_prepare_sample(&header, data, event, regs); |
5c148194 | 5527 | |
a7ac67ea | 5528 | if (perf_output_begin(&handle, event, header.size)) |
927c7a9e | 5529 | goto exit; |
0322cd6e | 5530 | |
cdd6c482 | 5531 | perf_output_sample(&handle, &header, data, event); |
f413cdb8 | 5532 | |
8a057d84 | 5533 | perf_output_end(&handle); |
927c7a9e FW |
5534 | |
5535 | exit: | |
5536 | rcu_read_unlock(); | |
0322cd6e PZ |
5537 | } |
5538 | ||
38b200d6 | 5539 | /* |
cdd6c482 | 5540 | * read event_id |
38b200d6 PZ |
5541 | */ |
5542 | ||
5543 | struct perf_read_event { | |
5544 | struct perf_event_header header; | |
5545 | ||
5546 | u32 pid; | |
5547 | u32 tid; | |
38b200d6 PZ |
5548 | }; |
5549 | ||
5550 | static void | |
cdd6c482 | 5551 | perf_event_read_event(struct perf_event *event, |
38b200d6 PZ |
5552 | struct task_struct *task) |
5553 | { | |
5554 | struct perf_output_handle handle; | |
c980d109 | 5555 | struct perf_sample_data sample; |
dfc65094 | 5556 | struct perf_read_event read_event = { |
38b200d6 | 5557 | .header = { |
cdd6c482 | 5558 | .type = PERF_RECORD_READ, |
38b200d6 | 5559 | .misc = 0, |
c320c7b7 | 5560 | .size = sizeof(read_event) + event->read_size, |
38b200d6 | 5561 | }, |
cdd6c482 IM |
5562 | .pid = perf_event_pid(event, task), |
5563 | .tid = perf_event_tid(event, task), | |
38b200d6 | 5564 | }; |
3dab77fb | 5565 | int ret; |
38b200d6 | 5566 | |
c980d109 | 5567 | perf_event_header__init_id(&read_event.header, &sample, event); |
a7ac67ea | 5568 | ret = perf_output_begin(&handle, event, read_event.header.size); |
38b200d6 PZ |
5569 | if (ret) |
5570 | return; | |
5571 | ||
dfc65094 | 5572 | perf_output_put(&handle, read_event); |
cdd6c482 | 5573 | perf_output_read(&handle, event); |
c980d109 | 5574 | perf_event__output_id_sample(event, &handle, &sample); |
3dab77fb | 5575 | |
38b200d6 PZ |
5576 | perf_output_end(&handle); |
5577 | } | |
5578 | ||
52d857a8 JO |
5579 | typedef void (perf_event_aux_output_cb)(struct perf_event *event, void *data); |
5580 | ||
5581 | static void | |
5582 | perf_event_aux_ctx(struct perf_event_context *ctx, | |
52d857a8 JO |
5583 | perf_event_aux_output_cb output, |
5584 | void *data) | |
5585 | { | |
5586 | struct perf_event *event; | |
5587 | ||
5588 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
5589 | if (event->state < PERF_EVENT_STATE_INACTIVE) | |
5590 | continue; | |
5591 | if (!event_filter_match(event)) | |
5592 | continue; | |
67516844 | 5593 | output(event, data); |
52d857a8 JO |
5594 | } |
5595 | } | |
5596 | ||
4e93ad60 JO |
5597 | static void |
5598 | perf_event_aux_task_ctx(perf_event_aux_output_cb output, void *data, | |
5599 | struct perf_event_context *task_ctx) | |
5600 | { | |
5601 | rcu_read_lock(); | |
5602 | preempt_disable(); | |
5603 | perf_event_aux_ctx(task_ctx, output, data); | |
5604 | preempt_enable(); | |
5605 | rcu_read_unlock(); | |
5606 | } | |
5607 | ||
52d857a8 | 5608 | static void |
67516844 | 5609 | perf_event_aux(perf_event_aux_output_cb output, void *data, |
52d857a8 JO |
5610 | struct perf_event_context *task_ctx) |
5611 | { | |
5612 | struct perf_cpu_context *cpuctx; | |
5613 | struct perf_event_context *ctx; | |
5614 | struct pmu *pmu; | |
5615 | int ctxn; | |
5616 | ||
4e93ad60 JO |
5617 | /* |
5618 | * If we have task_ctx != NULL we only notify | |
5619 | * the task context itself. The task_ctx is set | |
5620 | * only for EXIT events before releasing task | |
5621 | * context. | |
5622 | */ | |
5623 | if (task_ctx) { | |
5624 | perf_event_aux_task_ctx(output, data, task_ctx); | |
5625 | return; | |
5626 | } | |
5627 | ||
52d857a8 JO |
5628 | rcu_read_lock(); |
5629 | list_for_each_entry_rcu(pmu, &pmus, entry) { | |
5630 | cpuctx = get_cpu_ptr(pmu->pmu_cpu_context); | |
5631 | if (cpuctx->unique_pmu != pmu) | |
5632 | goto next; | |
67516844 | 5633 | perf_event_aux_ctx(&cpuctx->ctx, output, data); |
52d857a8 JO |
5634 | ctxn = pmu->task_ctx_nr; |
5635 | if (ctxn < 0) | |
5636 | goto next; | |
5637 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); | |
5638 | if (ctx) | |
67516844 | 5639 | perf_event_aux_ctx(ctx, output, data); |
52d857a8 JO |
5640 | next: |
5641 | put_cpu_ptr(pmu->pmu_cpu_context); | |
5642 | } | |
52d857a8 JO |
5643 | rcu_read_unlock(); |
5644 | } | |
5645 | ||
60313ebe | 5646 | /* |
9f498cc5 PZ |
5647 | * task tracking -- fork/exit |
5648 | * | |
13d7a241 | 5649 | * enabled by: attr.comm | attr.mmap | attr.mmap2 | attr.mmap_data | attr.task |
60313ebe PZ |
5650 | */ |
5651 | ||
9f498cc5 | 5652 | struct perf_task_event { |
3a80b4a3 | 5653 | struct task_struct *task; |
cdd6c482 | 5654 | struct perf_event_context *task_ctx; |
60313ebe PZ |
5655 | |
5656 | struct { | |
5657 | struct perf_event_header header; | |
5658 | ||
5659 | u32 pid; | |
5660 | u32 ppid; | |
9f498cc5 PZ |
5661 | u32 tid; |
5662 | u32 ptid; | |
393b2ad8 | 5663 | u64 time; |
cdd6c482 | 5664 | } event_id; |
60313ebe PZ |
5665 | }; |
5666 | ||
67516844 JO |
5667 | static int perf_event_task_match(struct perf_event *event) |
5668 | { | |
13d7a241 SE |
5669 | return event->attr.comm || event->attr.mmap || |
5670 | event->attr.mmap2 || event->attr.mmap_data || | |
5671 | event->attr.task; | |
67516844 JO |
5672 | } |
5673 | ||
cdd6c482 | 5674 | static void perf_event_task_output(struct perf_event *event, |
52d857a8 | 5675 | void *data) |
60313ebe | 5676 | { |
52d857a8 | 5677 | struct perf_task_event *task_event = data; |
60313ebe | 5678 | struct perf_output_handle handle; |
c980d109 | 5679 | struct perf_sample_data sample; |
9f498cc5 | 5680 | struct task_struct *task = task_event->task; |
c980d109 | 5681 | int ret, size = task_event->event_id.header.size; |
8bb39f9a | 5682 | |
67516844 JO |
5683 | if (!perf_event_task_match(event)) |
5684 | return; | |
5685 | ||
c980d109 | 5686 | perf_event_header__init_id(&task_event->event_id.header, &sample, event); |
60313ebe | 5687 | |
c980d109 | 5688 | ret = perf_output_begin(&handle, event, |
a7ac67ea | 5689 | task_event->event_id.header.size); |
ef60777c | 5690 | if (ret) |
c980d109 | 5691 | goto out; |
60313ebe | 5692 | |
cdd6c482 IM |
5693 | task_event->event_id.pid = perf_event_pid(event, task); |
5694 | task_event->event_id.ppid = perf_event_pid(event, current); | |
60313ebe | 5695 | |
cdd6c482 IM |
5696 | task_event->event_id.tid = perf_event_tid(event, task); |
5697 | task_event->event_id.ptid = perf_event_tid(event, current); | |
9f498cc5 | 5698 | |
34f43927 PZ |
5699 | task_event->event_id.time = perf_event_clock(event); |
5700 | ||
cdd6c482 | 5701 | perf_output_put(&handle, task_event->event_id); |
393b2ad8 | 5702 | |
c980d109 ACM |
5703 | perf_event__output_id_sample(event, &handle, &sample); |
5704 | ||
60313ebe | 5705 | perf_output_end(&handle); |
c980d109 ACM |
5706 | out: |
5707 | task_event->event_id.header.size = size; | |
60313ebe PZ |
5708 | } |
5709 | ||
cdd6c482 IM |
5710 | static void perf_event_task(struct task_struct *task, |
5711 | struct perf_event_context *task_ctx, | |
3a80b4a3 | 5712 | int new) |
60313ebe | 5713 | { |
9f498cc5 | 5714 | struct perf_task_event task_event; |
60313ebe | 5715 | |
cdd6c482 IM |
5716 | if (!atomic_read(&nr_comm_events) && |
5717 | !atomic_read(&nr_mmap_events) && | |
5718 | !atomic_read(&nr_task_events)) | |
60313ebe PZ |
5719 | return; |
5720 | ||
9f498cc5 | 5721 | task_event = (struct perf_task_event){ |
3a80b4a3 PZ |
5722 | .task = task, |
5723 | .task_ctx = task_ctx, | |
cdd6c482 | 5724 | .event_id = { |
60313ebe | 5725 | .header = { |
cdd6c482 | 5726 | .type = new ? PERF_RECORD_FORK : PERF_RECORD_EXIT, |
573402db | 5727 | .misc = 0, |
cdd6c482 | 5728 | .size = sizeof(task_event.event_id), |
60313ebe | 5729 | }, |
573402db PZ |
5730 | /* .pid */ |
5731 | /* .ppid */ | |
9f498cc5 PZ |
5732 | /* .tid */ |
5733 | /* .ptid */ | |
34f43927 | 5734 | /* .time */ |
60313ebe PZ |
5735 | }, |
5736 | }; | |
5737 | ||
67516844 | 5738 | perf_event_aux(perf_event_task_output, |
52d857a8 JO |
5739 | &task_event, |
5740 | task_ctx); | |
9f498cc5 PZ |
5741 | } |
5742 | ||
cdd6c482 | 5743 | void perf_event_fork(struct task_struct *task) |
9f498cc5 | 5744 | { |
cdd6c482 | 5745 | perf_event_task(task, NULL, 1); |
60313ebe PZ |
5746 | } |
5747 | ||
8d1b2d93 PZ |
5748 | /* |
5749 | * comm tracking | |
5750 | */ | |
5751 | ||
5752 | struct perf_comm_event { | |
22a4f650 IM |
5753 | struct task_struct *task; |
5754 | char *comm; | |
8d1b2d93 PZ |
5755 | int comm_size; |
5756 | ||
5757 | struct { | |
5758 | struct perf_event_header header; | |
5759 | ||
5760 | u32 pid; | |
5761 | u32 tid; | |
cdd6c482 | 5762 | } event_id; |
8d1b2d93 PZ |
5763 | }; |
5764 | ||
67516844 JO |
5765 | static int perf_event_comm_match(struct perf_event *event) |
5766 | { | |
5767 | return event->attr.comm; | |
5768 | } | |
5769 | ||
cdd6c482 | 5770 | static void perf_event_comm_output(struct perf_event *event, |
52d857a8 | 5771 | void *data) |
8d1b2d93 | 5772 | { |
52d857a8 | 5773 | struct perf_comm_event *comm_event = data; |
8d1b2d93 | 5774 | struct perf_output_handle handle; |
c980d109 | 5775 | struct perf_sample_data sample; |
cdd6c482 | 5776 | int size = comm_event->event_id.header.size; |
c980d109 ACM |
5777 | int ret; |
5778 | ||
67516844 JO |
5779 | if (!perf_event_comm_match(event)) |
5780 | return; | |
5781 | ||
c980d109 ACM |
5782 | perf_event_header__init_id(&comm_event->event_id.header, &sample, event); |
5783 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 5784 | comm_event->event_id.header.size); |
8d1b2d93 PZ |
5785 | |
5786 | if (ret) | |
c980d109 | 5787 | goto out; |
8d1b2d93 | 5788 | |
cdd6c482 IM |
5789 | comm_event->event_id.pid = perf_event_pid(event, comm_event->task); |
5790 | comm_event->event_id.tid = perf_event_tid(event, comm_event->task); | |
709e50cf | 5791 | |
cdd6c482 | 5792 | perf_output_put(&handle, comm_event->event_id); |
76369139 | 5793 | __output_copy(&handle, comm_event->comm, |
8d1b2d93 | 5794 | comm_event->comm_size); |
c980d109 ACM |
5795 | |
5796 | perf_event__output_id_sample(event, &handle, &sample); | |
5797 | ||
8d1b2d93 | 5798 | perf_output_end(&handle); |
c980d109 ACM |
5799 | out: |
5800 | comm_event->event_id.header.size = size; | |
8d1b2d93 PZ |
5801 | } |
5802 | ||
cdd6c482 | 5803 | static void perf_event_comm_event(struct perf_comm_event *comm_event) |
8d1b2d93 | 5804 | { |
413ee3b4 | 5805 | char comm[TASK_COMM_LEN]; |
8d1b2d93 | 5806 | unsigned int size; |
8d1b2d93 | 5807 | |
413ee3b4 | 5808 | memset(comm, 0, sizeof(comm)); |
96b02d78 | 5809 | strlcpy(comm, comm_event->task->comm, sizeof(comm)); |
888fcee0 | 5810 | size = ALIGN(strlen(comm)+1, sizeof(u64)); |
8d1b2d93 PZ |
5811 | |
5812 | comm_event->comm = comm; | |
5813 | comm_event->comm_size = size; | |
5814 | ||
cdd6c482 | 5815 | comm_event->event_id.header.size = sizeof(comm_event->event_id) + size; |
8dc85d54 | 5816 | |
67516844 | 5817 | perf_event_aux(perf_event_comm_output, |
52d857a8 JO |
5818 | comm_event, |
5819 | NULL); | |
8d1b2d93 PZ |
5820 | } |
5821 | ||
82b89778 | 5822 | void perf_event_comm(struct task_struct *task, bool exec) |
8d1b2d93 | 5823 | { |
9ee318a7 PZ |
5824 | struct perf_comm_event comm_event; |
5825 | ||
cdd6c482 | 5826 | if (!atomic_read(&nr_comm_events)) |
9ee318a7 | 5827 | return; |
a63eaf34 | 5828 | |
9ee318a7 | 5829 | comm_event = (struct perf_comm_event){ |
8d1b2d93 | 5830 | .task = task, |
573402db PZ |
5831 | /* .comm */ |
5832 | /* .comm_size */ | |
cdd6c482 | 5833 | .event_id = { |
573402db | 5834 | .header = { |
cdd6c482 | 5835 | .type = PERF_RECORD_COMM, |
82b89778 | 5836 | .misc = exec ? PERF_RECORD_MISC_COMM_EXEC : 0, |
573402db PZ |
5837 | /* .size */ |
5838 | }, | |
5839 | /* .pid */ | |
5840 | /* .tid */ | |
8d1b2d93 PZ |
5841 | }, |
5842 | }; | |
5843 | ||
cdd6c482 | 5844 | perf_event_comm_event(&comm_event); |
8d1b2d93 PZ |
5845 | } |
5846 | ||
0a4a9391 PZ |
5847 | /* |
5848 | * mmap tracking | |
5849 | */ | |
5850 | ||
5851 | struct perf_mmap_event { | |
089dd79d PZ |
5852 | struct vm_area_struct *vma; |
5853 | ||
5854 | const char *file_name; | |
5855 | int file_size; | |
13d7a241 SE |
5856 | int maj, min; |
5857 | u64 ino; | |
5858 | u64 ino_generation; | |
f972eb63 | 5859 | u32 prot, flags; |
0a4a9391 PZ |
5860 | |
5861 | struct { | |
5862 | struct perf_event_header header; | |
5863 | ||
5864 | u32 pid; | |
5865 | u32 tid; | |
5866 | u64 start; | |
5867 | u64 len; | |
5868 | u64 pgoff; | |
cdd6c482 | 5869 | } event_id; |
0a4a9391 PZ |
5870 | }; |
5871 | ||
67516844 JO |
5872 | static int perf_event_mmap_match(struct perf_event *event, |
5873 | void *data) | |
5874 | { | |
5875 | struct perf_mmap_event *mmap_event = data; | |
5876 | struct vm_area_struct *vma = mmap_event->vma; | |
5877 | int executable = vma->vm_flags & VM_EXEC; | |
5878 | ||
5879 | return (!executable && event->attr.mmap_data) || | |
13d7a241 | 5880 | (executable && (event->attr.mmap || event->attr.mmap2)); |
67516844 JO |
5881 | } |
5882 | ||
cdd6c482 | 5883 | static void perf_event_mmap_output(struct perf_event *event, |
52d857a8 | 5884 | void *data) |
0a4a9391 | 5885 | { |
52d857a8 | 5886 | struct perf_mmap_event *mmap_event = data; |
0a4a9391 | 5887 | struct perf_output_handle handle; |
c980d109 | 5888 | struct perf_sample_data sample; |
cdd6c482 | 5889 | int size = mmap_event->event_id.header.size; |
c980d109 | 5890 | int ret; |
0a4a9391 | 5891 | |
67516844 JO |
5892 | if (!perf_event_mmap_match(event, data)) |
5893 | return; | |
5894 | ||
13d7a241 SE |
5895 | if (event->attr.mmap2) { |
5896 | mmap_event->event_id.header.type = PERF_RECORD_MMAP2; | |
5897 | mmap_event->event_id.header.size += sizeof(mmap_event->maj); | |
5898 | mmap_event->event_id.header.size += sizeof(mmap_event->min); | |
5899 | mmap_event->event_id.header.size += sizeof(mmap_event->ino); | |
d008d525 | 5900 | mmap_event->event_id.header.size += sizeof(mmap_event->ino_generation); |
f972eb63 PZ |
5901 | mmap_event->event_id.header.size += sizeof(mmap_event->prot); |
5902 | mmap_event->event_id.header.size += sizeof(mmap_event->flags); | |
13d7a241 SE |
5903 | } |
5904 | ||
c980d109 ACM |
5905 | perf_event_header__init_id(&mmap_event->event_id.header, &sample, event); |
5906 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 5907 | mmap_event->event_id.header.size); |
0a4a9391 | 5908 | if (ret) |
c980d109 | 5909 | goto out; |
0a4a9391 | 5910 | |
cdd6c482 IM |
5911 | mmap_event->event_id.pid = perf_event_pid(event, current); |
5912 | mmap_event->event_id.tid = perf_event_tid(event, current); | |
709e50cf | 5913 | |
cdd6c482 | 5914 | perf_output_put(&handle, mmap_event->event_id); |
13d7a241 SE |
5915 | |
5916 | if (event->attr.mmap2) { | |
5917 | perf_output_put(&handle, mmap_event->maj); | |
5918 | perf_output_put(&handle, mmap_event->min); | |
5919 | perf_output_put(&handle, mmap_event->ino); | |
5920 | perf_output_put(&handle, mmap_event->ino_generation); | |
f972eb63 PZ |
5921 | perf_output_put(&handle, mmap_event->prot); |
5922 | perf_output_put(&handle, mmap_event->flags); | |
13d7a241 SE |
5923 | } |
5924 | ||
76369139 | 5925 | __output_copy(&handle, mmap_event->file_name, |
0a4a9391 | 5926 | mmap_event->file_size); |
c980d109 ACM |
5927 | |
5928 | perf_event__output_id_sample(event, &handle, &sample); | |
5929 | ||
78d613eb | 5930 | perf_output_end(&handle); |
c980d109 ACM |
5931 | out: |
5932 | mmap_event->event_id.header.size = size; | |
0a4a9391 PZ |
5933 | } |
5934 | ||
cdd6c482 | 5935 | static void perf_event_mmap_event(struct perf_mmap_event *mmap_event) |
0a4a9391 | 5936 | { |
089dd79d PZ |
5937 | struct vm_area_struct *vma = mmap_event->vma; |
5938 | struct file *file = vma->vm_file; | |
13d7a241 SE |
5939 | int maj = 0, min = 0; |
5940 | u64 ino = 0, gen = 0; | |
f972eb63 | 5941 | u32 prot = 0, flags = 0; |
0a4a9391 PZ |
5942 | unsigned int size; |
5943 | char tmp[16]; | |
5944 | char *buf = NULL; | |
2c42cfbf | 5945 | char *name; |
413ee3b4 | 5946 | |
0a4a9391 | 5947 | if (file) { |
13d7a241 SE |
5948 | struct inode *inode; |
5949 | dev_t dev; | |
3ea2f2b9 | 5950 | |
2c42cfbf | 5951 | buf = kmalloc(PATH_MAX, GFP_KERNEL); |
0a4a9391 | 5952 | if (!buf) { |
c7e548b4 ON |
5953 | name = "//enomem"; |
5954 | goto cpy_name; | |
0a4a9391 | 5955 | } |
413ee3b4 | 5956 | /* |
3ea2f2b9 | 5957 | * d_path() works from the end of the rb backwards, so we |
413ee3b4 AB |
5958 | * need to add enough zero bytes after the string to handle |
5959 | * the 64bit alignment we do later. | |
5960 | */ | |
9bf39ab2 | 5961 | name = file_path(file, buf, PATH_MAX - sizeof(u64)); |
0a4a9391 | 5962 | if (IS_ERR(name)) { |
c7e548b4 ON |
5963 | name = "//toolong"; |
5964 | goto cpy_name; | |
0a4a9391 | 5965 | } |
13d7a241 SE |
5966 | inode = file_inode(vma->vm_file); |
5967 | dev = inode->i_sb->s_dev; | |
5968 | ino = inode->i_ino; | |
5969 | gen = inode->i_generation; | |
5970 | maj = MAJOR(dev); | |
5971 | min = MINOR(dev); | |
f972eb63 PZ |
5972 | |
5973 | if (vma->vm_flags & VM_READ) | |
5974 | prot |= PROT_READ; | |
5975 | if (vma->vm_flags & VM_WRITE) | |
5976 | prot |= PROT_WRITE; | |
5977 | if (vma->vm_flags & VM_EXEC) | |
5978 | prot |= PROT_EXEC; | |
5979 | ||
5980 | if (vma->vm_flags & VM_MAYSHARE) | |
5981 | flags = MAP_SHARED; | |
5982 | else | |
5983 | flags = MAP_PRIVATE; | |
5984 | ||
5985 | if (vma->vm_flags & VM_DENYWRITE) | |
5986 | flags |= MAP_DENYWRITE; | |
5987 | if (vma->vm_flags & VM_MAYEXEC) | |
5988 | flags |= MAP_EXECUTABLE; | |
5989 | if (vma->vm_flags & VM_LOCKED) | |
5990 | flags |= MAP_LOCKED; | |
5991 | if (vma->vm_flags & VM_HUGETLB) | |
5992 | flags |= MAP_HUGETLB; | |
5993 | ||
c7e548b4 | 5994 | goto got_name; |
0a4a9391 | 5995 | } else { |
fbe26abe JO |
5996 | if (vma->vm_ops && vma->vm_ops->name) { |
5997 | name = (char *) vma->vm_ops->name(vma); | |
5998 | if (name) | |
5999 | goto cpy_name; | |
6000 | } | |
6001 | ||
2c42cfbf | 6002 | name = (char *)arch_vma_name(vma); |
c7e548b4 ON |
6003 | if (name) |
6004 | goto cpy_name; | |
089dd79d | 6005 | |
32c5fb7e | 6006 | if (vma->vm_start <= vma->vm_mm->start_brk && |
3af9e859 | 6007 | vma->vm_end >= vma->vm_mm->brk) { |
c7e548b4 ON |
6008 | name = "[heap]"; |
6009 | goto cpy_name; | |
32c5fb7e ON |
6010 | } |
6011 | if (vma->vm_start <= vma->vm_mm->start_stack && | |
3af9e859 | 6012 | vma->vm_end >= vma->vm_mm->start_stack) { |
c7e548b4 ON |
6013 | name = "[stack]"; |
6014 | goto cpy_name; | |
089dd79d PZ |
6015 | } |
6016 | ||
c7e548b4 ON |
6017 | name = "//anon"; |
6018 | goto cpy_name; | |
0a4a9391 PZ |
6019 | } |
6020 | ||
c7e548b4 ON |
6021 | cpy_name: |
6022 | strlcpy(tmp, name, sizeof(tmp)); | |
6023 | name = tmp; | |
0a4a9391 | 6024 | got_name: |
2c42cfbf PZ |
6025 | /* |
6026 | * Since our buffer works in 8 byte units we need to align our string | |
6027 | * size to a multiple of 8. However, we must guarantee the tail end is | |
6028 | * zero'd out to avoid leaking random bits to userspace. | |
6029 | */ | |
6030 | size = strlen(name)+1; | |
6031 | while (!IS_ALIGNED(size, sizeof(u64))) | |
6032 | name[size++] = '\0'; | |
0a4a9391 PZ |
6033 | |
6034 | mmap_event->file_name = name; | |
6035 | mmap_event->file_size = size; | |
13d7a241 SE |
6036 | mmap_event->maj = maj; |
6037 | mmap_event->min = min; | |
6038 | mmap_event->ino = ino; | |
6039 | mmap_event->ino_generation = gen; | |
f972eb63 PZ |
6040 | mmap_event->prot = prot; |
6041 | mmap_event->flags = flags; | |
0a4a9391 | 6042 | |
2fe85427 SE |
6043 | if (!(vma->vm_flags & VM_EXEC)) |
6044 | mmap_event->event_id.header.misc |= PERF_RECORD_MISC_MMAP_DATA; | |
6045 | ||
cdd6c482 | 6046 | mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size; |
0a4a9391 | 6047 | |
67516844 | 6048 | perf_event_aux(perf_event_mmap_output, |
52d857a8 JO |
6049 | mmap_event, |
6050 | NULL); | |
665c2142 | 6051 | |
0a4a9391 PZ |
6052 | kfree(buf); |
6053 | } | |
6054 | ||
3af9e859 | 6055 | void perf_event_mmap(struct vm_area_struct *vma) |
0a4a9391 | 6056 | { |
9ee318a7 PZ |
6057 | struct perf_mmap_event mmap_event; |
6058 | ||
cdd6c482 | 6059 | if (!atomic_read(&nr_mmap_events)) |
9ee318a7 PZ |
6060 | return; |
6061 | ||
6062 | mmap_event = (struct perf_mmap_event){ | |
089dd79d | 6063 | .vma = vma, |
573402db PZ |
6064 | /* .file_name */ |
6065 | /* .file_size */ | |
cdd6c482 | 6066 | .event_id = { |
573402db | 6067 | .header = { |
cdd6c482 | 6068 | .type = PERF_RECORD_MMAP, |
39447b38 | 6069 | .misc = PERF_RECORD_MISC_USER, |
573402db PZ |
6070 | /* .size */ |
6071 | }, | |
6072 | /* .pid */ | |
6073 | /* .tid */ | |
089dd79d PZ |
6074 | .start = vma->vm_start, |
6075 | .len = vma->vm_end - vma->vm_start, | |
3a0304e9 | 6076 | .pgoff = (u64)vma->vm_pgoff << PAGE_SHIFT, |
0a4a9391 | 6077 | }, |
13d7a241 SE |
6078 | /* .maj (attr_mmap2 only) */ |
6079 | /* .min (attr_mmap2 only) */ | |
6080 | /* .ino (attr_mmap2 only) */ | |
6081 | /* .ino_generation (attr_mmap2 only) */ | |
f972eb63 PZ |
6082 | /* .prot (attr_mmap2 only) */ |
6083 | /* .flags (attr_mmap2 only) */ | |
0a4a9391 PZ |
6084 | }; |
6085 | ||
cdd6c482 | 6086 | perf_event_mmap_event(&mmap_event); |
0a4a9391 PZ |
6087 | } |
6088 | ||
68db7e98 AS |
6089 | void perf_event_aux_event(struct perf_event *event, unsigned long head, |
6090 | unsigned long size, u64 flags) | |
6091 | { | |
6092 | struct perf_output_handle handle; | |
6093 | struct perf_sample_data sample; | |
6094 | struct perf_aux_event { | |
6095 | struct perf_event_header header; | |
6096 | u64 offset; | |
6097 | u64 size; | |
6098 | u64 flags; | |
6099 | } rec = { | |
6100 | .header = { | |
6101 | .type = PERF_RECORD_AUX, | |
6102 | .misc = 0, | |
6103 | .size = sizeof(rec), | |
6104 | }, | |
6105 | .offset = head, | |
6106 | .size = size, | |
6107 | .flags = flags, | |
6108 | }; | |
6109 | int ret; | |
6110 | ||
6111 | perf_event_header__init_id(&rec.header, &sample, event); | |
6112 | ret = perf_output_begin(&handle, event, rec.header.size); | |
6113 | ||
6114 | if (ret) | |
6115 | return; | |
6116 | ||
6117 | perf_output_put(&handle, rec); | |
6118 | perf_event__output_id_sample(event, &handle, &sample); | |
6119 | ||
6120 | perf_output_end(&handle); | |
6121 | } | |
6122 | ||
f38b0dbb KL |
6123 | /* |
6124 | * Lost/dropped samples logging | |
6125 | */ | |
6126 | void perf_log_lost_samples(struct perf_event *event, u64 lost) | |
6127 | { | |
6128 | struct perf_output_handle handle; | |
6129 | struct perf_sample_data sample; | |
6130 | int ret; | |
6131 | ||
6132 | struct { | |
6133 | struct perf_event_header header; | |
6134 | u64 lost; | |
6135 | } lost_samples_event = { | |
6136 | .header = { | |
6137 | .type = PERF_RECORD_LOST_SAMPLES, | |
6138 | .misc = 0, | |
6139 | .size = sizeof(lost_samples_event), | |
6140 | }, | |
6141 | .lost = lost, | |
6142 | }; | |
6143 | ||
6144 | perf_event_header__init_id(&lost_samples_event.header, &sample, event); | |
6145 | ||
6146 | ret = perf_output_begin(&handle, event, | |
6147 | lost_samples_event.header.size); | |
6148 | if (ret) | |
6149 | return; | |
6150 | ||
6151 | perf_output_put(&handle, lost_samples_event); | |
6152 | perf_event__output_id_sample(event, &handle, &sample); | |
6153 | perf_output_end(&handle); | |
6154 | } | |
6155 | ||
45ac1403 AH |
6156 | /* |
6157 | * context_switch tracking | |
6158 | */ | |
6159 | ||
6160 | struct perf_switch_event { | |
6161 | struct task_struct *task; | |
6162 | struct task_struct *next_prev; | |
6163 | ||
6164 | struct { | |
6165 | struct perf_event_header header; | |
6166 | u32 next_prev_pid; | |
6167 | u32 next_prev_tid; | |
6168 | } event_id; | |
6169 | }; | |
6170 | ||
6171 | static int perf_event_switch_match(struct perf_event *event) | |
6172 | { | |
6173 | return event->attr.context_switch; | |
6174 | } | |
6175 | ||
6176 | static void perf_event_switch_output(struct perf_event *event, void *data) | |
6177 | { | |
6178 | struct perf_switch_event *se = data; | |
6179 | struct perf_output_handle handle; | |
6180 | struct perf_sample_data sample; | |
6181 | int ret; | |
6182 | ||
6183 | if (!perf_event_switch_match(event)) | |
6184 | return; | |
6185 | ||
6186 | /* Only CPU-wide events are allowed to see next/prev pid/tid */ | |
6187 | if (event->ctx->task) { | |
6188 | se->event_id.header.type = PERF_RECORD_SWITCH; | |
6189 | se->event_id.header.size = sizeof(se->event_id.header); | |
6190 | } else { | |
6191 | se->event_id.header.type = PERF_RECORD_SWITCH_CPU_WIDE; | |
6192 | se->event_id.header.size = sizeof(se->event_id); | |
6193 | se->event_id.next_prev_pid = | |
6194 | perf_event_pid(event, se->next_prev); | |
6195 | se->event_id.next_prev_tid = | |
6196 | perf_event_tid(event, se->next_prev); | |
6197 | } | |
6198 | ||
6199 | perf_event_header__init_id(&se->event_id.header, &sample, event); | |
6200 | ||
6201 | ret = perf_output_begin(&handle, event, se->event_id.header.size); | |
6202 | if (ret) | |
6203 | return; | |
6204 | ||
6205 | if (event->ctx->task) | |
6206 | perf_output_put(&handle, se->event_id.header); | |
6207 | else | |
6208 | perf_output_put(&handle, se->event_id); | |
6209 | ||
6210 | perf_event__output_id_sample(event, &handle, &sample); | |
6211 | ||
6212 | perf_output_end(&handle); | |
6213 | } | |
6214 | ||
6215 | static void perf_event_switch(struct task_struct *task, | |
6216 | struct task_struct *next_prev, bool sched_in) | |
6217 | { | |
6218 | struct perf_switch_event switch_event; | |
6219 | ||
6220 | /* N.B. caller checks nr_switch_events != 0 */ | |
6221 | ||
6222 | switch_event = (struct perf_switch_event){ | |
6223 | .task = task, | |
6224 | .next_prev = next_prev, | |
6225 | .event_id = { | |
6226 | .header = { | |
6227 | /* .type */ | |
6228 | .misc = sched_in ? 0 : PERF_RECORD_MISC_SWITCH_OUT, | |
6229 | /* .size */ | |
6230 | }, | |
6231 | /* .next_prev_pid */ | |
6232 | /* .next_prev_tid */ | |
6233 | }, | |
6234 | }; | |
6235 | ||
6236 | perf_event_aux(perf_event_switch_output, | |
6237 | &switch_event, | |
6238 | NULL); | |
6239 | } | |
6240 | ||
a78ac325 PZ |
6241 | /* |
6242 | * IRQ throttle logging | |
6243 | */ | |
6244 | ||
cdd6c482 | 6245 | static void perf_log_throttle(struct perf_event *event, int enable) |
a78ac325 PZ |
6246 | { |
6247 | struct perf_output_handle handle; | |
c980d109 | 6248 | struct perf_sample_data sample; |
a78ac325 PZ |
6249 | int ret; |
6250 | ||
6251 | struct { | |
6252 | struct perf_event_header header; | |
6253 | u64 time; | |
cca3f454 | 6254 | u64 id; |
7f453c24 | 6255 | u64 stream_id; |
a78ac325 PZ |
6256 | } throttle_event = { |
6257 | .header = { | |
cdd6c482 | 6258 | .type = PERF_RECORD_THROTTLE, |
a78ac325 PZ |
6259 | .misc = 0, |
6260 | .size = sizeof(throttle_event), | |
6261 | }, | |
34f43927 | 6262 | .time = perf_event_clock(event), |
cdd6c482 IM |
6263 | .id = primary_event_id(event), |
6264 | .stream_id = event->id, | |
a78ac325 PZ |
6265 | }; |
6266 | ||
966ee4d6 | 6267 | if (enable) |
cdd6c482 | 6268 | throttle_event.header.type = PERF_RECORD_UNTHROTTLE; |
966ee4d6 | 6269 | |
c980d109 ACM |
6270 | perf_event_header__init_id(&throttle_event.header, &sample, event); |
6271 | ||
6272 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 6273 | throttle_event.header.size); |
a78ac325 PZ |
6274 | if (ret) |
6275 | return; | |
6276 | ||
6277 | perf_output_put(&handle, throttle_event); | |
c980d109 | 6278 | perf_event__output_id_sample(event, &handle, &sample); |
a78ac325 PZ |
6279 | perf_output_end(&handle); |
6280 | } | |
6281 | ||
ec0d7729 AS |
6282 | static void perf_log_itrace_start(struct perf_event *event) |
6283 | { | |
6284 | struct perf_output_handle handle; | |
6285 | struct perf_sample_data sample; | |
6286 | struct perf_aux_event { | |
6287 | struct perf_event_header header; | |
6288 | u32 pid; | |
6289 | u32 tid; | |
6290 | } rec; | |
6291 | int ret; | |
6292 | ||
6293 | if (event->parent) | |
6294 | event = event->parent; | |
6295 | ||
6296 | if (!(event->pmu->capabilities & PERF_PMU_CAP_ITRACE) || | |
6297 | event->hw.itrace_started) | |
6298 | return; | |
6299 | ||
ec0d7729 AS |
6300 | rec.header.type = PERF_RECORD_ITRACE_START; |
6301 | rec.header.misc = 0; | |
6302 | rec.header.size = sizeof(rec); | |
6303 | rec.pid = perf_event_pid(event, current); | |
6304 | rec.tid = perf_event_tid(event, current); | |
6305 | ||
6306 | perf_event_header__init_id(&rec.header, &sample, event); | |
6307 | ret = perf_output_begin(&handle, event, rec.header.size); | |
6308 | ||
6309 | if (ret) | |
6310 | return; | |
6311 | ||
6312 | perf_output_put(&handle, rec); | |
6313 | perf_event__output_id_sample(event, &handle, &sample); | |
6314 | ||
6315 | perf_output_end(&handle); | |
6316 | } | |
6317 | ||
f6c7d5fe | 6318 | /* |
cdd6c482 | 6319 | * Generic event overflow handling, sampling. |
f6c7d5fe PZ |
6320 | */ |
6321 | ||
a8b0ca17 | 6322 | static int __perf_event_overflow(struct perf_event *event, |
5622f295 MM |
6323 | int throttle, struct perf_sample_data *data, |
6324 | struct pt_regs *regs) | |
f6c7d5fe | 6325 | { |
cdd6c482 IM |
6326 | int events = atomic_read(&event->event_limit); |
6327 | struct hw_perf_event *hwc = &event->hw; | |
e050e3f0 | 6328 | u64 seq; |
79f14641 PZ |
6329 | int ret = 0; |
6330 | ||
96398826 PZ |
6331 | /* |
6332 | * Non-sampling counters might still use the PMI to fold short | |
6333 | * hardware counters, ignore those. | |
6334 | */ | |
6335 | if (unlikely(!is_sampling_event(event))) | |
6336 | return 0; | |
6337 | ||
e050e3f0 SE |
6338 | seq = __this_cpu_read(perf_throttled_seq); |
6339 | if (seq != hwc->interrupts_seq) { | |
6340 | hwc->interrupts_seq = seq; | |
6341 | hwc->interrupts = 1; | |
6342 | } else { | |
6343 | hwc->interrupts++; | |
6344 | if (unlikely(throttle | |
6345 | && hwc->interrupts >= max_samples_per_tick)) { | |
6346 | __this_cpu_inc(perf_throttled_count); | |
163ec435 PZ |
6347 | hwc->interrupts = MAX_INTERRUPTS; |
6348 | perf_log_throttle(event, 0); | |
d84153d6 | 6349 | tick_nohz_full_kick(); |
a78ac325 PZ |
6350 | ret = 1; |
6351 | } | |
e050e3f0 | 6352 | } |
60db5e09 | 6353 | |
cdd6c482 | 6354 | if (event->attr.freq) { |
def0a9b2 | 6355 | u64 now = perf_clock(); |
abd50713 | 6356 | s64 delta = now - hwc->freq_time_stamp; |
bd2b5b12 | 6357 | |
abd50713 | 6358 | hwc->freq_time_stamp = now; |
bd2b5b12 | 6359 | |
abd50713 | 6360 | if (delta > 0 && delta < 2*TICK_NSEC) |
f39d47ff | 6361 | perf_adjust_period(event, delta, hwc->last_period, true); |
bd2b5b12 PZ |
6362 | } |
6363 | ||
2023b359 PZ |
6364 | /* |
6365 | * XXX event_limit might not quite work as expected on inherited | |
cdd6c482 | 6366 | * events |
2023b359 PZ |
6367 | */ |
6368 | ||
cdd6c482 IM |
6369 | event->pending_kill = POLL_IN; |
6370 | if (events && atomic_dec_and_test(&event->event_limit)) { | |
79f14641 | 6371 | ret = 1; |
cdd6c482 | 6372 | event->pending_kill = POLL_HUP; |
a8b0ca17 PZ |
6373 | event->pending_disable = 1; |
6374 | irq_work_queue(&event->pending); | |
79f14641 PZ |
6375 | } |
6376 | ||
453f19ee | 6377 | if (event->overflow_handler) |
a8b0ca17 | 6378 | event->overflow_handler(event, data, regs); |
453f19ee | 6379 | else |
a8b0ca17 | 6380 | perf_event_output(event, data, regs); |
453f19ee | 6381 | |
fed66e2c | 6382 | if (*perf_event_fasync(event) && event->pending_kill) { |
a8b0ca17 PZ |
6383 | event->pending_wakeup = 1; |
6384 | irq_work_queue(&event->pending); | |
f506b3dc PZ |
6385 | } |
6386 | ||
79f14641 | 6387 | return ret; |
f6c7d5fe PZ |
6388 | } |
6389 | ||
a8b0ca17 | 6390 | int perf_event_overflow(struct perf_event *event, |
5622f295 MM |
6391 | struct perf_sample_data *data, |
6392 | struct pt_regs *regs) | |
850bc73f | 6393 | { |
a8b0ca17 | 6394 | return __perf_event_overflow(event, 1, data, regs); |
850bc73f PZ |
6395 | } |
6396 | ||
15dbf27c | 6397 | /* |
cdd6c482 | 6398 | * Generic software event infrastructure |
15dbf27c PZ |
6399 | */ |
6400 | ||
b28ab83c PZ |
6401 | struct swevent_htable { |
6402 | struct swevent_hlist *swevent_hlist; | |
6403 | struct mutex hlist_mutex; | |
6404 | int hlist_refcount; | |
6405 | ||
6406 | /* Recursion avoidance in each contexts */ | |
6407 | int recursion[PERF_NR_CONTEXTS]; | |
6408 | }; | |
6409 | ||
6410 | static DEFINE_PER_CPU(struct swevent_htable, swevent_htable); | |
6411 | ||
7b4b6658 | 6412 | /* |
cdd6c482 IM |
6413 | * We directly increment event->count and keep a second value in |
6414 | * event->hw.period_left to count intervals. This period event | |
7b4b6658 PZ |
6415 | * is kept in the range [-sample_period, 0] so that we can use the |
6416 | * sign as trigger. | |
6417 | */ | |
6418 | ||
ab573844 | 6419 | u64 perf_swevent_set_period(struct perf_event *event) |
15dbf27c | 6420 | { |
cdd6c482 | 6421 | struct hw_perf_event *hwc = &event->hw; |
7b4b6658 PZ |
6422 | u64 period = hwc->last_period; |
6423 | u64 nr, offset; | |
6424 | s64 old, val; | |
6425 | ||
6426 | hwc->last_period = hwc->sample_period; | |
15dbf27c PZ |
6427 | |
6428 | again: | |
e7850595 | 6429 | old = val = local64_read(&hwc->period_left); |
7b4b6658 PZ |
6430 | if (val < 0) |
6431 | return 0; | |
15dbf27c | 6432 | |
7b4b6658 PZ |
6433 | nr = div64_u64(period + val, period); |
6434 | offset = nr * period; | |
6435 | val -= offset; | |
e7850595 | 6436 | if (local64_cmpxchg(&hwc->period_left, old, val) != old) |
7b4b6658 | 6437 | goto again; |
15dbf27c | 6438 | |
7b4b6658 | 6439 | return nr; |
15dbf27c PZ |
6440 | } |
6441 | ||
0cff784a | 6442 | static void perf_swevent_overflow(struct perf_event *event, u64 overflow, |
a8b0ca17 | 6443 | struct perf_sample_data *data, |
5622f295 | 6444 | struct pt_regs *regs) |
15dbf27c | 6445 | { |
cdd6c482 | 6446 | struct hw_perf_event *hwc = &event->hw; |
850bc73f | 6447 | int throttle = 0; |
15dbf27c | 6448 | |
0cff784a PZ |
6449 | if (!overflow) |
6450 | overflow = perf_swevent_set_period(event); | |
15dbf27c | 6451 | |
7b4b6658 PZ |
6452 | if (hwc->interrupts == MAX_INTERRUPTS) |
6453 | return; | |
15dbf27c | 6454 | |
7b4b6658 | 6455 | for (; overflow; overflow--) { |
a8b0ca17 | 6456 | if (__perf_event_overflow(event, throttle, |
5622f295 | 6457 | data, regs)) { |
7b4b6658 PZ |
6458 | /* |
6459 | * We inhibit the overflow from happening when | |
6460 | * hwc->interrupts == MAX_INTERRUPTS. | |
6461 | */ | |
6462 | break; | |
6463 | } | |
cf450a73 | 6464 | throttle = 1; |
7b4b6658 | 6465 | } |
15dbf27c PZ |
6466 | } |
6467 | ||
a4eaf7f1 | 6468 | static void perf_swevent_event(struct perf_event *event, u64 nr, |
a8b0ca17 | 6469 | struct perf_sample_data *data, |
5622f295 | 6470 | struct pt_regs *regs) |
7b4b6658 | 6471 | { |
cdd6c482 | 6472 | struct hw_perf_event *hwc = &event->hw; |
d6d020e9 | 6473 | |
e7850595 | 6474 | local64_add(nr, &event->count); |
d6d020e9 | 6475 | |
0cff784a PZ |
6476 | if (!regs) |
6477 | return; | |
6478 | ||
6c7e550f | 6479 | if (!is_sampling_event(event)) |
7b4b6658 | 6480 | return; |
d6d020e9 | 6481 | |
5d81e5cf AV |
6482 | if ((event->attr.sample_type & PERF_SAMPLE_PERIOD) && !event->attr.freq) { |
6483 | data->period = nr; | |
6484 | return perf_swevent_overflow(event, 1, data, regs); | |
6485 | } else | |
6486 | data->period = event->hw.last_period; | |
6487 | ||
0cff784a | 6488 | if (nr == 1 && hwc->sample_period == 1 && !event->attr.freq) |
a8b0ca17 | 6489 | return perf_swevent_overflow(event, 1, data, regs); |
0cff784a | 6490 | |
e7850595 | 6491 | if (local64_add_negative(nr, &hwc->period_left)) |
7b4b6658 | 6492 | return; |
df1a132b | 6493 | |
a8b0ca17 | 6494 | perf_swevent_overflow(event, 0, data, regs); |
d6d020e9 PZ |
6495 | } |
6496 | ||
f5ffe02e FW |
6497 | static int perf_exclude_event(struct perf_event *event, |
6498 | struct pt_regs *regs) | |
6499 | { | |
a4eaf7f1 | 6500 | if (event->hw.state & PERF_HES_STOPPED) |
91b2f482 | 6501 | return 1; |
a4eaf7f1 | 6502 | |
f5ffe02e FW |
6503 | if (regs) { |
6504 | if (event->attr.exclude_user && user_mode(regs)) | |
6505 | return 1; | |
6506 | ||
6507 | if (event->attr.exclude_kernel && !user_mode(regs)) | |
6508 | return 1; | |
6509 | } | |
6510 | ||
6511 | return 0; | |
6512 | } | |
6513 | ||
cdd6c482 | 6514 | static int perf_swevent_match(struct perf_event *event, |
1c432d89 | 6515 | enum perf_type_id type, |
6fb2915d LZ |
6516 | u32 event_id, |
6517 | struct perf_sample_data *data, | |
6518 | struct pt_regs *regs) | |
15dbf27c | 6519 | { |
cdd6c482 | 6520 | if (event->attr.type != type) |
a21ca2ca | 6521 | return 0; |
f5ffe02e | 6522 | |
cdd6c482 | 6523 | if (event->attr.config != event_id) |
15dbf27c PZ |
6524 | return 0; |
6525 | ||
f5ffe02e FW |
6526 | if (perf_exclude_event(event, regs)) |
6527 | return 0; | |
15dbf27c PZ |
6528 | |
6529 | return 1; | |
6530 | } | |
6531 | ||
76e1d904 FW |
6532 | static inline u64 swevent_hash(u64 type, u32 event_id) |
6533 | { | |
6534 | u64 val = event_id | (type << 32); | |
6535 | ||
6536 | return hash_64(val, SWEVENT_HLIST_BITS); | |
6537 | } | |
6538 | ||
49f135ed FW |
6539 | static inline struct hlist_head * |
6540 | __find_swevent_head(struct swevent_hlist *hlist, u64 type, u32 event_id) | |
76e1d904 | 6541 | { |
49f135ed FW |
6542 | u64 hash = swevent_hash(type, event_id); |
6543 | ||
6544 | return &hlist->heads[hash]; | |
6545 | } | |
76e1d904 | 6546 | |
49f135ed FW |
6547 | /* For the read side: events when they trigger */ |
6548 | static inline struct hlist_head * | |
b28ab83c | 6549 | find_swevent_head_rcu(struct swevent_htable *swhash, u64 type, u32 event_id) |
49f135ed FW |
6550 | { |
6551 | struct swevent_hlist *hlist; | |
76e1d904 | 6552 | |
b28ab83c | 6553 | hlist = rcu_dereference(swhash->swevent_hlist); |
76e1d904 FW |
6554 | if (!hlist) |
6555 | return NULL; | |
6556 | ||
49f135ed FW |
6557 | return __find_swevent_head(hlist, type, event_id); |
6558 | } | |
6559 | ||
6560 | /* For the event head insertion and removal in the hlist */ | |
6561 | static inline struct hlist_head * | |
b28ab83c | 6562 | find_swevent_head(struct swevent_htable *swhash, struct perf_event *event) |
49f135ed FW |
6563 | { |
6564 | struct swevent_hlist *hlist; | |
6565 | u32 event_id = event->attr.config; | |
6566 | u64 type = event->attr.type; | |
6567 | ||
6568 | /* | |
6569 | * Event scheduling is always serialized against hlist allocation | |
6570 | * and release. Which makes the protected version suitable here. | |
6571 | * The context lock guarantees that. | |
6572 | */ | |
b28ab83c | 6573 | hlist = rcu_dereference_protected(swhash->swevent_hlist, |
49f135ed FW |
6574 | lockdep_is_held(&event->ctx->lock)); |
6575 | if (!hlist) | |
6576 | return NULL; | |
6577 | ||
6578 | return __find_swevent_head(hlist, type, event_id); | |
76e1d904 FW |
6579 | } |
6580 | ||
6581 | static void do_perf_sw_event(enum perf_type_id type, u32 event_id, | |
a8b0ca17 | 6582 | u64 nr, |
76e1d904 FW |
6583 | struct perf_sample_data *data, |
6584 | struct pt_regs *regs) | |
15dbf27c | 6585 | { |
4a32fea9 | 6586 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 6587 | struct perf_event *event; |
76e1d904 | 6588 | struct hlist_head *head; |
15dbf27c | 6589 | |
76e1d904 | 6590 | rcu_read_lock(); |
b28ab83c | 6591 | head = find_swevent_head_rcu(swhash, type, event_id); |
76e1d904 FW |
6592 | if (!head) |
6593 | goto end; | |
6594 | ||
b67bfe0d | 6595 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
6fb2915d | 6596 | if (perf_swevent_match(event, type, event_id, data, regs)) |
a8b0ca17 | 6597 | perf_swevent_event(event, nr, data, regs); |
15dbf27c | 6598 | } |
76e1d904 FW |
6599 | end: |
6600 | rcu_read_unlock(); | |
15dbf27c PZ |
6601 | } |
6602 | ||
86038c5e PZI |
6603 | DEFINE_PER_CPU(struct pt_regs, __perf_regs[4]); |
6604 | ||
4ed7c92d | 6605 | int perf_swevent_get_recursion_context(void) |
96f6d444 | 6606 | { |
4a32fea9 | 6607 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
96f6d444 | 6608 | |
b28ab83c | 6609 | return get_recursion_context(swhash->recursion); |
96f6d444 | 6610 | } |
645e8cc0 | 6611 | EXPORT_SYMBOL_GPL(perf_swevent_get_recursion_context); |
96f6d444 | 6612 | |
fa9f90be | 6613 | inline void perf_swevent_put_recursion_context(int rctx) |
15dbf27c | 6614 | { |
4a32fea9 | 6615 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
927c7a9e | 6616 | |
b28ab83c | 6617 | put_recursion_context(swhash->recursion, rctx); |
ce71b9df | 6618 | } |
15dbf27c | 6619 | |
86038c5e | 6620 | void ___perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) |
b8e83514 | 6621 | { |
a4234bfc | 6622 | struct perf_sample_data data; |
4ed7c92d | 6623 | |
86038c5e | 6624 | if (WARN_ON_ONCE(!regs)) |
4ed7c92d | 6625 | return; |
a4234bfc | 6626 | |
fd0d000b | 6627 | perf_sample_data_init(&data, addr, 0); |
a8b0ca17 | 6628 | do_perf_sw_event(PERF_TYPE_SOFTWARE, event_id, nr, &data, regs); |
86038c5e PZI |
6629 | } |
6630 | ||
6631 | void __perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) | |
6632 | { | |
6633 | int rctx; | |
6634 | ||
6635 | preempt_disable_notrace(); | |
6636 | rctx = perf_swevent_get_recursion_context(); | |
6637 | if (unlikely(rctx < 0)) | |
6638 | goto fail; | |
6639 | ||
6640 | ___perf_sw_event(event_id, nr, regs, addr); | |
4ed7c92d PZ |
6641 | |
6642 | perf_swevent_put_recursion_context(rctx); | |
86038c5e | 6643 | fail: |
1c024eca | 6644 | preempt_enable_notrace(); |
b8e83514 PZ |
6645 | } |
6646 | ||
cdd6c482 | 6647 | static void perf_swevent_read(struct perf_event *event) |
15dbf27c | 6648 | { |
15dbf27c PZ |
6649 | } |
6650 | ||
a4eaf7f1 | 6651 | static int perf_swevent_add(struct perf_event *event, int flags) |
15dbf27c | 6652 | { |
4a32fea9 | 6653 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 6654 | struct hw_perf_event *hwc = &event->hw; |
76e1d904 FW |
6655 | struct hlist_head *head; |
6656 | ||
6c7e550f | 6657 | if (is_sampling_event(event)) { |
7b4b6658 | 6658 | hwc->last_period = hwc->sample_period; |
cdd6c482 | 6659 | perf_swevent_set_period(event); |
7b4b6658 | 6660 | } |
76e1d904 | 6661 | |
a4eaf7f1 PZ |
6662 | hwc->state = !(flags & PERF_EF_START); |
6663 | ||
b28ab83c | 6664 | head = find_swevent_head(swhash, event); |
12ca6ad2 | 6665 | if (WARN_ON_ONCE(!head)) |
76e1d904 FW |
6666 | return -EINVAL; |
6667 | ||
6668 | hlist_add_head_rcu(&event->hlist_entry, head); | |
6a694a60 | 6669 | perf_event_update_userpage(event); |
76e1d904 | 6670 | |
15dbf27c PZ |
6671 | return 0; |
6672 | } | |
6673 | ||
a4eaf7f1 | 6674 | static void perf_swevent_del(struct perf_event *event, int flags) |
15dbf27c | 6675 | { |
76e1d904 | 6676 | hlist_del_rcu(&event->hlist_entry); |
15dbf27c PZ |
6677 | } |
6678 | ||
a4eaf7f1 | 6679 | static void perf_swevent_start(struct perf_event *event, int flags) |
5c92d124 | 6680 | { |
a4eaf7f1 | 6681 | event->hw.state = 0; |
d6d020e9 | 6682 | } |
aa9c4c0f | 6683 | |
a4eaf7f1 | 6684 | static void perf_swevent_stop(struct perf_event *event, int flags) |
d6d020e9 | 6685 | { |
a4eaf7f1 | 6686 | event->hw.state = PERF_HES_STOPPED; |
bae43c99 IM |
6687 | } |
6688 | ||
49f135ed FW |
6689 | /* Deref the hlist from the update side */ |
6690 | static inline struct swevent_hlist * | |
b28ab83c | 6691 | swevent_hlist_deref(struct swevent_htable *swhash) |
49f135ed | 6692 | { |
b28ab83c PZ |
6693 | return rcu_dereference_protected(swhash->swevent_hlist, |
6694 | lockdep_is_held(&swhash->hlist_mutex)); | |
49f135ed FW |
6695 | } |
6696 | ||
b28ab83c | 6697 | static void swevent_hlist_release(struct swevent_htable *swhash) |
76e1d904 | 6698 | { |
b28ab83c | 6699 | struct swevent_hlist *hlist = swevent_hlist_deref(swhash); |
76e1d904 | 6700 | |
49f135ed | 6701 | if (!hlist) |
76e1d904 FW |
6702 | return; |
6703 | ||
70691d4a | 6704 | RCU_INIT_POINTER(swhash->swevent_hlist, NULL); |
fa4bbc4c | 6705 | kfree_rcu(hlist, rcu_head); |
76e1d904 FW |
6706 | } |
6707 | ||
6708 | static void swevent_hlist_put_cpu(struct perf_event *event, int cpu) | |
6709 | { | |
b28ab83c | 6710 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 | 6711 | |
b28ab83c | 6712 | mutex_lock(&swhash->hlist_mutex); |
76e1d904 | 6713 | |
b28ab83c PZ |
6714 | if (!--swhash->hlist_refcount) |
6715 | swevent_hlist_release(swhash); | |
76e1d904 | 6716 | |
b28ab83c | 6717 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
6718 | } |
6719 | ||
6720 | static void swevent_hlist_put(struct perf_event *event) | |
6721 | { | |
6722 | int cpu; | |
6723 | ||
76e1d904 FW |
6724 | for_each_possible_cpu(cpu) |
6725 | swevent_hlist_put_cpu(event, cpu); | |
6726 | } | |
6727 | ||
6728 | static int swevent_hlist_get_cpu(struct perf_event *event, int cpu) | |
6729 | { | |
b28ab83c | 6730 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 FW |
6731 | int err = 0; |
6732 | ||
b28ab83c | 6733 | mutex_lock(&swhash->hlist_mutex); |
b28ab83c | 6734 | if (!swevent_hlist_deref(swhash) && cpu_online(cpu)) { |
76e1d904 FW |
6735 | struct swevent_hlist *hlist; |
6736 | ||
6737 | hlist = kzalloc(sizeof(*hlist), GFP_KERNEL); | |
6738 | if (!hlist) { | |
6739 | err = -ENOMEM; | |
6740 | goto exit; | |
6741 | } | |
b28ab83c | 6742 | rcu_assign_pointer(swhash->swevent_hlist, hlist); |
76e1d904 | 6743 | } |
b28ab83c | 6744 | swhash->hlist_refcount++; |
9ed6060d | 6745 | exit: |
b28ab83c | 6746 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
6747 | |
6748 | return err; | |
6749 | } | |
6750 | ||
6751 | static int swevent_hlist_get(struct perf_event *event) | |
6752 | { | |
6753 | int err; | |
6754 | int cpu, failed_cpu; | |
6755 | ||
76e1d904 FW |
6756 | get_online_cpus(); |
6757 | for_each_possible_cpu(cpu) { | |
6758 | err = swevent_hlist_get_cpu(event, cpu); | |
6759 | if (err) { | |
6760 | failed_cpu = cpu; | |
6761 | goto fail; | |
6762 | } | |
6763 | } | |
6764 | put_online_cpus(); | |
6765 | ||
6766 | return 0; | |
9ed6060d | 6767 | fail: |
76e1d904 FW |
6768 | for_each_possible_cpu(cpu) { |
6769 | if (cpu == failed_cpu) | |
6770 | break; | |
6771 | swevent_hlist_put_cpu(event, cpu); | |
6772 | } | |
6773 | ||
6774 | put_online_cpus(); | |
6775 | return err; | |
6776 | } | |
6777 | ||
c5905afb | 6778 | struct static_key perf_swevent_enabled[PERF_COUNT_SW_MAX]; |
95476b64 | 6779 | |
b0a873eb PZ |
6780 | static void sw_perf_event_destroy(struct perf_event *event) |
6781 | { | |
6782 | u64 event_id = event->attr.config; | |
95476b64 | 6783 | |
b0a873eb PZ |
6784 | WARN_ON(event->parent); |
6785 | ||
c5905afb | 6786 | static_key_slow_dec(&perf_swevent_enabled[event_id]); |
b0a873eb PZ |
6787 | swevent_hlist_put(event); |
6788 | } | |
6789 | ||
6790 | static int perf_swevent_init(struct perf_event *event) | |
6791 | { | |
8176cced | 6792 | u64 event_id = event->attr.config; |
b0a873eb PZ |
6793 | |
6794 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
6795 | return -ENOENT; | |
6796 | ||
2481c5fa SE |
6797 | /* |
6798 | * no branch sampling for software events | |
6799 | */ | |
6800 | if (has_branch_stack(event)) | |
6801 | return -EOPNOTSUPP; | |
6802 | ||
b0a873eb PZ |
6803 | switch (event_id) { |
6804 | case PERF_COUNT_SW_CPU_CLOCK: | |
6805 | case PERF_COUNT_SW_TASK_CLOCK: | |
6806 | return -ENOENT; | |
6807 | ||
6808 | default: | |
6809 | break; | |
6810 | } | |
6811 | ||
ce677831 | 6812 | if (event_id >= PERF_COUNT_SW_MAX) |
b0a873eb PZ |
6813 | return -ENOENT; |
6814 | ||
6815 | if (!event->parent) { | |
6816 | int err; | |
6817 | ||
6818 | err = swevent_hlist_get(event); | |
6819 | if (err) | |
6820 | return err; | |
6821 | ||
c5905afb | 6822 | static_key_slow_inc(&perf_swevent_enabled[event_id]); |
b0a873eb PZ |
6823 | event->destroy = sw_perf_event_destroy; |
6824 | } | |
6825 | ||
6826 | return 0; | |
6827 | } | |
6828 | ||
6829 | static struct pmu perf_swevent = { | |
89a1e187 | 6830 | .task_ctx_nr = perf_sw_context, |
95476b64 | 6831 | |
34f43927 PZ |
6832 | .capabilities = PERF_PMU_CAP_NO_NMI, |
6833 | ||
b0a873eb | 6834 | .event_init = perf_swevent_init, |
a4eaf7f1 PZ |
6835 | .add = perf_swevent_add, |
6836 | .del = perf_swevent_del, | |
6837 | .start = perf_swevent_start, | |
6838 | .stop = perf_swevent_stop, | |
1c024eca | 6839 | .read = perf_swevent_read, |
1c024eca PZ |
6840 | }; |
6841 | ||
b0a873eb PZ |
6842 | #ifdef CONFIG_EVENT_TRACING |
6843 | ||
1c024eca PZ |
6844 | static int perf_tp_filter_match(struct perf_event *event, |
6845 | struct perf_sample_data *data) | |
6846 | { | |
6847 | void *record = data->raw->data; | |
6848 | ||
b71b437e PZ |
6849 | /* only top level events have filters set */ |
6850 | if (event->parent) | |
6851 | event = event->parent; | |
6852 | ||
1c024eca PZ |
6853 | if (likely(!event->filter) || filter_match_preds(event->filter, record)) |
6854 | return 1; | |
6855 | return 0; | |
6856 | } | |
6857 | ||
6858 | static int perf_tp_event_match(struct perf_event *event, | |
6859 | struct perf_sample_data *data, | |
6860 | struct pt_regs *regs) | |
6861 | { | |
a0f7d0f7 FW |
6862 | if (event->hw.state & PERF_HES_STOPPED) |
6863 | return 0; | |
580d607c PZ |
6864 | /* |
6865 | * All tracepoints are from kernel-space. | |
6866 | */ | |
6867 | if (event->attr.exclude_kernel) | |
1c024eca PZ |
6868 | return 0; |
6869 | ||
6870 | if (!perf_tp_filter_match(event, data)) | |
6871 | return 0; | |
6872 | ||
6873 | return 1; | |
6874 | } | |
6875 | ||
6876 | void perf_tp_event(u64 addr, u64 count, void *record, int entry_size, | |
e6dab5ff AV |
6877 | struct pt_regs *regs, struct hlist_head *head, int rctx, |
6878 | struct task_struct *task) | |
95476b64 FW |
6879 | { |
6880 | struct perf_sample_data data; | |
1c024eca | 6881 | struct perf_event *event; |
1c024eca | 6882 | |
95476b64 FW |
6883 | struct perf_raw_record raw = { |
6884 | .size = entry_size, | |
6885 | .data = record, | |
6886 | }; | |
6887 | ||
fd0d000b | 6888 | perf_sample_data_init(&data, addr, 0); |
95476b64 FW |
6889 | data.raw = &raw; |
6890 | ||
b67bfe0d | 6891 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
1c024eca | 6892 | if (perf_tp_event_match(event, &data, regs)) |
a8b0ca17 | 6893 | perf_swevent_event(event, count, &data, regs); |
4f41c013 | 6894 | } |
ecc55f84 | 6895 | |
e6dab5ff AV |
6896 | /* |
6897 | * If we got specified a target task, also iterate its context and | |
6898 | * deliver this event there too. | |
6899 | */ | |
6900 | if (task && task != current) { | |
6901 | struct perf_event_context *ctx; | |
6902 | struct trace_entry *entry = record; | |
6903 | ||
6904 | rcu_read_lock(); | |
6905 | ctx = rcu_dereference(task->perf_event_ctxp[perf_sw_context]); | |
6906 | if (!ctx) | |
6907 | goto unlock; | |
6908 | ||
6909 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
6910 | if (event->attr.type != PERF_TYPE_TRACEPOINT) | |
6911 | continue; | |
6912 | if (event->attr.config != entry->type) | |
6913 | continue; | |
6914 | if (perf_tp_event_match(event, &data, regs)) | |
6915 | perf_swevent_event(event, count, &data, regs); | |
6916 | } | |
6917 | unlock: | |
6918 | rcu_read_unlock(); | |
6919 | } | |
6920 | ||
ecc55f84 | 6921 | perf_swevent_put_recursion_context(rctx); |
95476b64 FW |
6922 | } |
6923 | EXPORT_SYMBOL_GPL(perf_tp_event); | |
6924 | ||
cdd6c482 | 6925 | static void tp_perf_event_destroy(struct perf_event *event) |
e077df4f | 6926 | { |
1c024eca | 6927 | perf_trace_destroy(event); |
e077df4f PZ |
6928 | } |
6929 | ||
b0a873eb | 6930 | static int perf_tp_event_init(struct perf_event *event) |
e077df4f | 6931 | { |
76e1d904 FW |
6932 | int err; |
6933 | ||
b0a873eb PZ |
6934 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
6935 | return -ENOENT; | |
6936 | ||
2481c5fa SE |
6937 | /* |
6938 | * no branch sampling for tracepoint events | |
6939 | */ | |
6940 | if (has_branch_stack(event)) | |
6941 | return -EOPNOTSUPP; | |
6942 | ||
1c024eca PZ |
6943 | err = perf_trace_init(event); |
6944 | if (err) | |
b0a873eb | 6945 | return err; |
e077df4f | 6946 | |
cdd6c482 | 6947 | event->destroy = tp_perf_event_destroy; |
e077df4f | 6948 | |
b0a873eb PZ |
6949 | return 0; |
6950 | } | |
6951 | ||
6952 | static struct pmu perf_tracepoint = { | |
89a1e187 PZ |
6953 | .task_ctx_nr = perf_sw_context, |
6954 | ||
b0a873eb | 6955 | .event_init = perf_tp_event_init, |
a4eaf7f1 PZ |
6956 | .add = perf_trace_add, |
6957 | .del = perf_trace_del, | |
6958 | .start = perf_swevent_start, | |
6959 | .stop = perf_swevent_stop, | |
b0a873eb | 6960 | .read = perf_swevent_read, |
b0a873eb PZ |
6961 | }; |
6962 | ||
6963 | static inline void perf_tp_register(void) | |
6964 | { | |
2e80a82a | 6965 | perf_pmu_register(&perf_tracepoint, "tracepoint", PERF_TYPE_TRACEPOINT); |
e077df4f | 6966 | } |
6fb2915d LZ |
6967 | |
6968 | static int perf_event_set_filter(struct perf_event *event, void __user *arg) | |
6969 | { | |
6970 | char *filter_str; | |
6971 | int ret; | |
6972 | ||
6973 | if (event->attr.type != PERF_TYPE_TRACEPOINT) | |
6974 | return -EINVAL; | |
6975 | ||
6976 | filter_str = strndup_user(arg, PAGE_SIZE); | |
6977 | if (IS_ERR(filter_str)) | |
6978 | return PTR_ERR(filter_str); | |
6979 | ||
6980 | ret = ftrace_profile_set_filter(event, event->attr.config, filter_str); | |
6981 | ||
6982 | kfree(filter_str); | |
6983 | return ret; | |
6984 | } | |
6985 | ||
6986 | static void perf_event_free_filter(struct perf_event *event) | |
6987 | { | |
6988 | ftrace_profile_free_filter(event); | |
6989 | } | |
6990 | ||
2541517c AS |
6991 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
6992 | { | |
6993 | struct bpf_prog *prog; | |
6994 | ||
6995 | if (event->attr.type != PERF_TYPE_TRACEPOINT) | |
6996 | return -EINVAL; | |
6997 | ||
6998 | if (event->tp_event->prog) | |
6999 | return -EEXIST; | |
7000 | ||
04a22fae WN |
7001 | if (!(event->tp_event->flags & TRACE_EVENT_FL_UKPROBE)) |
7002 | /* bpf programs can only be attached to u/kprobes */ | |
2541517c AS |
7003 | return -EINVAL; |
7004 | ||
7005 | prog = bpf_prog_get(prog_fd); | |
7006 | if (IS_ERR(prog)) | |
7007 | return PTR_ERR(prog); | |
7008 | ||
6c373ca8 | 7009 | if (prog->type != BPF_PROG_TYPE_KPROBE) { |
2541517c AS |
7010 | /* valid fd, but invalid bpf program type */ |
7011 | bpf_prog_put(prog); | |
7012 | return -EINVAL; | |
7013 | } | |
7014 | ||
7015 | event->tp_event->prog = prog; | |
7016 | ||
7017 | return 0; | |
7018 | } | |
7019 | ||
7020 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
7021 | { | |
7022 | struct bpf_prog *prog; | |
7023 | ||
7024 | if (!event->tp_event) | |
7025 | return; | |
7026 | ||
7027 | prog = event->tp_event->prog; | |
7028 | if (prog) { | |
7029 | event->tp_event->prog = NULL; | |
7030 | bpf_prog_put(prog); | |
7031 | } | |
7032 | } | |
7033 | ||
e077df4f | 7034 | #else |
6fb2915d | 7035 | |
b0a873eb | 7036 | static inline void perf_tp_register(void) |
e077df4f | 7037 | { |
e077df4f | 7038 | } |
6fb2915d LZ |
7039 | |
7040 | static int perf_event_set_filter(struct perf_event *event, void __user *arg) | |
7041 | { | |
7042 | return -ENOENT; | |
7043 | } | |
7044 | ||
7045 | static void perf_event_free_filter(struct perf_event *event) | |
7046 | { | |
7047 | } | |
7048 | ||
2541517c AS |
7049 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
7050 | { | |
7051 | return -ENOENT; | |
7052 | } | |
7053 | ||
7054 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
7055 | { | |
7056 | } | |
07b139c8 | 7057 | #endif /* CONFIG_EVENT_TRACING */ |
e077df4f | 7058 | |
24f1e32c | 7059 | #ifdef CONFIG_HAVE_HW_BREAKPOINT |
f5ffe02e | 7060 | void perf_bp_event(struct perf_event *bp, void *data) |
24f1e32c | 7061 | { |
f5ffe02e FW |
7062 | struct perf_sample_data sample; |
7063 | struct pt_regs *regs = data; | |
7064 | ||
fd0d000b | 7065 | perf_sample_data_init(&sample, bp->attr.bp_addr, 0); |
f5ffe02e | 7066 | |
a4eaf7f1 | 7067 | if (!bp->hw.state && !perf_exclude_event(bp, regs)) |
a8b0ca17 | 7068 | perf_swevent_event(bp, 1, &sample, regs); |
24f1e32c FW |
7069 | } |
7070 | #endif | |
7071 | ||
b0a873eb PZ |
7072 | /* |
7073 | * hrtimer based swevent callback | |
7074 | */ | |
f29ac756 | 7075 | |
b0a873eb | 7076 | static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer) |
f29ac756 | 7077 | { |
b0a873eb PZ |
7078 | enum hrtimer_restart ret = HRTIMER_RESTART; |
7079 | struct perf_sample_data data; | |
7080 | struct pt_regs *regs; | |
7081 | struct perf_event *event; | |
7082 | u64 period; | |
f29ac756 | 7083 | |
b0a873eb | 7084 | event = container_of(hrtimer, struct perf_event, hw.hrtimer); |
ba3dd36c PZ |
7085 | |
7086 | if (event->state != PERF_EVENT_STATE_ACTIVE) | |
7087 | return HRTIMER_NORESTART; | |
7088 | ||
b0a873eb | 7089 | event->pmu->read(event); |
f344011c | 7090 | |
fd0d000b | 7091 | perf_sample_data_init(&data, 0, event->hw.last_period); |
b0a873eb PZ |
7092 | regs = get_irq_regs(); |
7093 | ||
7094 | if (regs && !perf_exclude_event(event, regs)) { | |
77aeeebd | 7095 | if (!(event->attr.exclude_idle && is_idle_task(current))) |
33b07b8b | 7096 | if (__perf_event_overflow(event, 1, &data, regs)) |
b0a873eb PZ |
7097 | ret = HRTIMER_NORESTART; |
7098 | } | |
24f1e32c | 7099 | |
b0a873eb PZ |
7100 | period = max_t(u64, 10000, event->hw.sample_period); |
7101 | hrtimer_forward_now(hrtimer, ns_to_ktime(period)); | |
24f1e32c | 7102 | |
b0a873eb | 7103 | return ret; |
f29ac756 PZ |
7104 | } |
7105 | ||
b0a873eb | 7106 | static void perf_swevent_start_hrtimer(struct perf_event *event) |
5c92d124 | 7107 | { |
b0a873eb | 7108 | struct hw_perf_event *hwc = &event->hw; |
5d508e82 FBH |
7109 | s64 period; |
7110 | ||
7111 | if (!is_sampling_event(event)) | |
7112 | return; | |
f5ffe02e | 7113 | |
5d508e82 FBH |
7114 | period = local64_read(&hwc->period_left); |
7115 | if (period) { | |
7116 | if (period < 0) | |
7117 | period = 10000; | |
fa407f35 | 7118 | |
5d508e82 FBH |
7119 | local64_set(&hwc->period_left, 0); |
7120 | } else { | |
7121 | period = max_t(u64, 10000, hwc->sample_period); | |
7122 | } | |
3497d206 TG |
7123 | hrtimer_start(&hwc->hrtimer, ns_to_ktime(period), |
7124 | HRTIMER_MODE_REL_PINNED); | |
24f1e32c | 7125 | } |
b0a873eb PZ |
7126 | |
7127 | static void perf_swevent_cancel_hrtimer(struct perf_event *event) | |
24f1e32c | 7128 | { |
b0a873eb PZ |
7129 | struct hw_perf_event *hwc = &event->hw; |
7130 | ||
6c7e550f | 7131 | if (is_sampling_event(event)) { |
b0a873eb | 7132 | ktime_t remaining = hrtimer_get_remaining(&hwc->hrtimer); |
fa407f35 | 7133 | local64_set(&hwc->period_left, ktime_to_ns(remaining)); |
b0a873eb PZ |
7134 | |
7135 | hrtimer_cancel(&hwc->hrtimer); | |
7136 | } | |
24f1e32c FW |
7137 | } |
7138 | ||
ba3dd36c PZ |
7139 | static void perf_swevent_init_hrtimer(struct perf_event *event) |
7140 | { | |
7141 | struct hw_perf_event *hwc = &event->hw; | |
7142 | ||
7143 | if (!is_sampling_event(event)) | |
7144 | return; | |
7145 | ||
7146 | hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); | |
7147 | hwc->hrtimer.function = perf_swevent_hrtimer; | |
7148 | ||
7149 | /* | |
7150 | * Since hrtimers have a fixed rate, we can do a static freq->period | |
7151 | * mapping and avoid the whole period adjust feedback stuff. | |
7152 | */ | |
7153 | if (event->attr.freq) { | |
7154 | long freq = event->attr.sample_freq; | |
7155 | ||
7156 | event->attr.sample_period = NSEC_PER_SEC / freq; | |
7157 | hwc->sample_period = event->attr.sample_period; | |
7158 | local64_set(&hwc->period_left, hwc->sample_period); | |
778141e3 | 7159 | hwc->last_period = hwc->sample_period; |
ba3dd36c PZ |
7160 | event->attr.freq = 0; |
7161 | } | |
7162 | } | |
7163 | ||
b0a873eb PZ |
7164 | /* |
7165 | * Software event: cpu wall time clock | |
7166 | */ | |
7167 | ||
7168 | static void cpu_clock_event_update(struct perf_event *event) | |
24f1e32c | 7169 | { |
b0a873eb PZ |
7170 | s64 prev; |
7171 | u64 now; | |
7172 | ||
a4eaf7f1 | 7173 | now = local_clock(); |
b0a873eb PZ |
7174 | prev = local64_xchg(&event->hw.prev_count, now); |
7175 | local64_add(now - prev, &event->count); | |
24f1e32c | 7176 | } |
24f1e32c | 7177 | |
a4eaf7f1 | 7178 | static void cpu_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 7179 | { |
a4eaf7f1 | 7180 | local64_set(&event->hw.prev_count, local_clock()); |
b0a873eb | 7181 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
7182 | } |
7183 | ||
a4eaf7f1 | 7184 | static void cpu_clock_event_stop(struct perf_event *event, int flags) |
f29ac756 | 7185 | { |
b0a873eb PZ |
7186 | perf_swevent_cancel_hrtimer(event); |
7187 | cpu_clock_event_update(event); | |
7188 | } | |
f29ac756 | 7189 | |
a4eaf7f1 PZ |
7190 | static int cpu_clock_event_add(struct perf_event *event, int flags) |
7191 | { | |
7192 | if (flags & PERF_EF_START) | |
7193 | cpu_clock_event_start(event, flags); | |
6a694a60 | 7194 | perf_event_update_userpage(event); |
a4eaf7f1 PZ |
7195 | |
7196 | return 0; | |
7197 | } | |
7198 | ||
7199 | static void cpu_clock_event_del(struct perf_event *event, int flags) | |
7200 | { | |
7201 | cpu_clock_event_stop(event, flags); | |
7202 | } | |
7203 | ||
b0a873eb PZ |
7204 | static void cpu_clock_event_read(struct perf_event *event) |
7205 | { | |
7206 | cpu_clock_event_update(event); | |
7207 | } | |
f344011c | 7208 | |
b0a873eb PZ |
7209 | static int cpu_clock_event_init(struct perf_event *event) |
7210 | { | |
7211 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
7212 | return -ENOENT; | |
7213 | ||
7214 | if (event->attr.config != PERF_COUNT_SW_CPU_CLOCK) | |
7215 | return -ENOENT; | |
7216 | ||
2481c5fa SE |
7217 | /* |
7218 | * no branch sampling for software events | |
7219 | */ | |
7220 | if (has_branch_stack(event)) | |
7221 | return -EOPNOTSUPP; | |
7222 | ||
ba3dd36c PZ |
7223 | perf_swevent_init_hrtimer(event); |
7224 | ||
b0a873eb | 7225 | return 0; |
f29ac756 PZ |
7226 | } |
7227 | ||
b0a873eb | 7228 | static struct pmu perf_cpu_clock = { |
89a1e187 PZ |
7229 | .task_ctx_nr = perf_sw_context, |
7230 | ||
34f43927 PZ |
7231 | .capabilities = PERF_PMU_CAP_NO_NMI, |
7232 | ||
b0a873eb | 7233 | .event_init = cpu_clock_event_init, |
a4eaf7f1 PZ |
7234 | .add = cpu_clock_event_add, |
7235 | .del = cpu_clock_event_del, | |
7236 | .start = cpu_clock_event_start, | |
7237 | .stop = cpu_clock_event_stop, | |
b0a873eb PZ |
7238 | .read = cpu_clock_event_read, |
7239 | }; | |
7240 | ||
7241 | /* | |
7242 | * Software event: task time clock | |
7243 | */ | |
7244 | ||
7245 | static void task_clock_event_update(struct perf_event *event, u64 now) | |
5c92d124 | 7246 | { |
b0a873eb PZ |
7247 | u64 prev; |
7248 | s64 delta; | |
5c92d124 | 7249 | |
b0a873eb PZ |
7250 | prev = local64_xchg(&event->hw.prev_count, now); |
7251 | delta = now - prev; | |
7252 | local64_add(delta, &event->count); | |
7253 | } | |
5c92d124 | 7254 | |
a4eaf7f1 | 7255 | static void task_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 7256 | { |
a4eaf7f1 | 7257 | local64_set(&event->hw.prev_count, event->ctx->time); |
b0a873eb | 7258 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
7259 | } |
7260 | ||
a4eaf7f1 | 7261 | static void task_clock_event_stop(struct perf_event *event, int flags) |
b0a873eb PZ |
7262 | { |
7263 | perf_swevent_cancel_hrtimer(event); | |
7264 | task_clock_event_update(event, event->ctx->time); | |
a4eaf7f1 PZ |
7265 | } |
7266 | ||
7267 | static int task_clock_event_add(struct perf_event *event, int flags) | |
7268 | { | |
7269 | if (flags & PERF_EF_START) | |
7270 | task_clock_event_start(event, flags); | |
6a694a60 | 7271 | perf_event_update_userpage(event); |
b0a873eb | 7272 | |
a4eaf7f1 PZ |
7273 | return 0; |
7274 | } | |
7275 | ||
7276 | static void task_clock_event_del(struct perf_event *event, int flags) | |
7277 | { | |
7278 | task_clock_event_stop(event, PERF_EF_UPDATE); | |
b0a873eb PZ |
7279 | } |
7280 | ||
7281 | static void task_clock_event_read(struct perf_event *event) | |
7282 | { | |
768a06e2 PZ |
7283 | u64 now = perf_clock(); |
7284 | u64 delta = now - event->ctx->timestamp; | |
7285 | u64 time = event->ctx->time + delta; | |
b0a873eb PZ |
7286 | |
7287 | task_clock_event_update(event, time); | |
7288 | } | |
7289 | ||
7290 | static int task_clock_event_init(struct perf_event *event) | |
6fb2915d | 7291 | { |
b0a873eb PZ |
7292 | if (event->attr.type != PERF_TYPE_SOFTWARE) |
7293 | return -ENOENT; | |
7294 | ||
7295 | if (event->attr.config != PERF_COUNT_SW_TASK_CLOCK) | |
7296 | return -ENOENT; | |
7297 | ||
2481c5fa SE |
7298 | /* |
7299 | * no branch sampling for software events | |
7300 | */ | |
7301 | if (has_branch_stack(event)) | |
7302 | return -EOPNOTSUPP; | |
7303 | ||
ba3dd36c PZ |
7304 | perf_swevent_init_hrtimer(event); |
7305 | ||
b0a873eb | 7306 | return 0; |
6fb2915d LZ |
7307 | } |
7308 | ||
b0a873eb | 7309 | static struct pmu perf_task_clock = { |
89a1e187 PZ |
7310 | .task_ctx_nr = perf_sw_context, |
7311 | ||
34f43927 PZ |
7312 | .capabilities = PERF_PMU_CAP_NO_NMI, |
7313 | ||
b0a873eb | 7314 | .event_init = task_clock_event_init, |
a4eaf7f1 PZ |
7315 | .add = task_clock_event_add, |
7316 | .del = task_clock_event_del, | |
7317 | .start = task_clock_event_start, | |
7318 | .stop = task_clock_event_stop, | |
b0a873eb PZ |
7319 | .read = task_clock_event_read, |
7320 | }; | |
6fb2915d | 7321 | |
ad5133b7 | 7322 | static void perf_pmu_nop_void(struct pmu *pmu) |
e077df4f | 7323 | { |
e077df4f | 7324 | } |
6fb2915d | 7325 | |
fbbe0701 SB |
7326 | static void perf_pmu_nop_txn(struct pmu *pmu, unsigned int flags) |
7327 | { | |
7328 | } | |
7329 | ||
ad5133b7 | 7330 | static int perf_pmu_nop_int(struct pmu *pmu) |
6fb2915d | 7331 | { |
ad5133b7 | 7332 | return 0; |
6fb2915d LZ |
7333 | } |
7334 | ||
18ab2cd3 | 7335 | static DEFINE_PER_CPU(unsigned int, nop_txn_flags); |
fbbe0701 SB |
7336 | |
7337 | static void perf_pmu_start_txn(struct pmu *pmu, unsigned int flags) | |
6fb2915d | 7338 | { |
fbbe0701 SB |
7339 | __this_cpu_write(nop_txn_flags, flags); |
7340 | ||
7341 | if (flags & ~PERF_PMU_TXN_ADD) | |
7342 | return; | |
7343 | ||
ad5133b7 | 7344 | perf_pmu_disable(pmu); |
6fb2915d LZ |
7345 | } |
7346 | ||
ad5133b7 PZ |
7347 | static int perf_pmu_commit_txn(struct pmu *pmu) |
7348 | { | |
fbbe0701 SB |
7349 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
7350 | ||
7351 | __this_cpu_write(nop_txn_flags, 0); | |
7352 | ||
7353 | if (flags & ~PERF_PMU_TXN_ADD) | |
7354 | return 0; | |
7355 | ||
ad5133b7 PZ |
7356 | perf_pmu_enable(pmu); |
7357 | return 0; | |
7358 | } | |
e077df4f | 7359 | |
ad5133b7 | 7360 | static void perf_pmu_cancel_txn(struct pmu *pmu) |
24f1e32c | 7361 | { |
fbbe0701 SB |
7362 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
7363 | ||
7364 | __this_cpu_write(nop_txn_flags, 0); | |
7365 | ||
7366 | if (flags & ~PERF_PMU_TXN_ADD) | |
7367 | return; | |
7368 | ||
ad5133b7 | 7369 | perf_pmu_enable(pmu); |
24f1e32c FW |
7370 | } |
7371 | ||
35edc2a5 PZ |
7372 | static int perf_event_idx_default(struct perf_event *event) |
7373 | { | |
c719f560 | 7374 | return 0; |
35edc2a5 PZ |
7375 | } |
7376 | ||
8dc85d54 PZ |
7377 | /* |
7378 | * Ensures all contexts with the same task_ctx_nr have the same | |
7379 | * pmu_cpu_context too. | |
7380 | */ | |
9e317041 | 7381 | static struct perf_cpu_context __percpu *find_pmu_context(int ctxn) |
24f1e32c | 7382 | { |
8dc85d54 | 7383 | struct pmu *pmu; |
b326e956 | 7384 | |
8dc85d54 PZ |
7385 | if (ctxn < 0) |
7386 | return NULL; | |
24f1e32c | 7387 | |
8dc85d54 PZ |
7388 | list_for_each_entry(pmu, &pmus, entry) { |
7389 | if (pmu->task_ctx_nr == ctxn) | |
7390 | return pmu->pmu_cpu_context; | |
7391 | } | |
24f1e32c | 7392 | |
8dc85d54 | 7393 | return NULL; |
24f1e32c FW |
7394 | } |
7395 | ||
51676957 | 7396 | static void update_pmu_context(struct pmu *pmu, struct pmu *old_pmu) |
24f1e32c | 7397 | { |
51676957 PZ |
7398 | int cpu; |
7399 | ||
7400 | for_each_possible_cpu(cpu) { | |
7401 | struct perf_cpu_context *cpuctx; | |
7402 | ||
7403 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
7404 | ||
3f1f3320 PZ |
7405 | if (cpuctx->unique_pmu == old_pmu) |
7406 | cpuctx->unique_pmu = pmu; | |
51676957 PZ |
7407 | } |
7408 | } | |
7409 | ||
7410 | static void free_pmu_context(struct pmu *pmu) | |
7411 | { | |
7412 | struct pmu *i; | |
f5ffe02e | 7413 | |
8dc85d54 | 7414 | mutex_lock(&pmus_lock); |
0475f9ea | 7415 | /* |
8dc85d54 | 7416 | * Like a real lame refcount. |
0475f9ea | 7417 | */ |
51676957 PZ |
7418 | list_for_each_entry(i, &pmus, entry) { |
7419 | if (i->pmu_cpu_context == pmu->pmu_cpu_context) { | |
7420 | update_pmu_context(i, pmu); | |
8dc85d54 | 7421 | goto out; |
51676957 | 7422 | } |
8dc85d54 | 7423 | } |
d6d020e9 | 7424 | |
51676957 | 7425 | free_percpu(pmu->pmu_cpu_context); |
8dc85d54 PZ |
7426 | out: |
7427 | mutex_unlock(&pmus_lock); | |
24f1e32c | 7428 | } |
2e80a82a | 7429 | static struct idr pmu_idr; |
d6d020e9 | 7430 | |
abe43400 PZ |
7431 | static ssize_t |
7432 | type_show(struct device *dev, struct device_attribute *attr, char *page) | |
7433 | { | |
7434 | struct pmu *pmu = dev_get_drvdata(dev); | |
7435 | ||
7436 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->type); | |
7437 | } | |
90826ca7 | 7438 | static DEVICE_ATTR_RO(type); |
abe43400 | 7439 | |
62b85639 SE |
7440 | static ssize_t |
7441 | perf_event_mux_interval_ms_show(struct device *dev, | |
7442 | struct device_attribute *attr, | |
7443 | char *page) | |
7444 | { | |
7445 | struct pmu *pmu = dev_get_drvdata(dev); | |
7446 | ||
7447 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->hrtimer_interval_ms); | |
7448 | } | |
7449 | ||
272325c4 PZ |
7450 | static DEFINE_MUTEX(mux_interval_mutex); |
7451 | ||
62b85639 SE |
7452 | static ssize_t |
7453 | perf_event_mux_interval_ms_store(struct device *dev, | |
7454 | struct device_attribute *attr, | |
7455 | const char *buf, size_t count) | |
7456 | { | |
7457 | struct pmu *pmu = dev_get_drvdata(dev); | |
7458 | int timer, cpu, ret; | |
7459 | ||
7460 | ret = kstrtoint(buf, 0, &timer); | |
7461 | if (ret) | |
7462 | return ret; | |
7463 | ||
7464 | if (timer < 1) | |
7465 | return -EINVAL; | |
7466 | ||
7467 | /* same value, noting to do */ | |
7468 | if (timer == pmu->hrtimer_interval_ms) | |
7469 | return count; | |
7470 | ||
272325c4 | 7471 | mutex_lock(&mux_interval_mutex); |
62b85639 SE |
7472 | pmu->hrtimer_interval_ms = timer; |
7473 | ||
7474 | /* update all cpuctx for this PMU */ | |
272325c4 PZ |
7475 | get_online_cpus(); |
7476 | for_each_online_cpu(cpu) { | |
62b85639 SE |
7477 | struct perf_cpu_context *cpuctx; |
7478 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
7479 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * timer); | |
7480 | ||
272325c4 PZ |
7481 | cpu_function_call(cpu, |
7482 | (remote_function_f)perf_mux_hrtimer_restart, cpuctx); | |
62b85639 | 7483 | } |
272325c4 PZ |
7484 | put_online_cpus(); |
7485 | mutex_unlock(&mux_interval_mutex); | |
62b85639 SE |
7486 | |
7487 | return count; | |
7488 | } | |
90826ca7 | 7489 | static DEVICE_ATTR_RW(perf_event_mux_interval_ms); |
62b85639 | 7490 | |
90826ca7 GKH |
7491 | static struct attribute *pmu_dev_attrs[] = { |
7492 | &dev_attr_type.attr, | |
7493 | &dev_attr_perf_event_mux_interval_ms.attr, | |
7494 | NULL, | |
abe43400 | 7495 | }; |
90826ca7 | 7496 | ATTRIBUTE_GROUPS(pmu_dev); |
abe43400 PZ |
7497 | |
7498 | static int pmu_bus_running; | |
7499 | static struct bus_type pmu_bus = { | |
7500 | .name = "event_source", | |
90826ca7 | 7501 | .dev_groups = pmu_dev_groups, |
abe43400 PZ |
7502 | }; |
7503 | ||
7504 | static void pmu_dev_release(struct device *dev) | |
7505 | { | |
7506 | kfree(dev); | |
7507 | } | |
7508 | ||
7509 | static int pmu_dev_alloc(struct pmu *pmu) | |
7510 | { | |
7511 | int ret = -ENOMEM; | |
7512 | ||
7513 | pmu->dev = kzalloc(sizeof(struct device), GFP_KERNEL); | |
7514 | if (!pmu->dev) | |
7515 | goto out; | |
7516 | ||
0c9d42ed | 7517 | pmu->dev->groups = pmu->attr_groups; |
abe43400 PZ |
7518 | device_initialize(pmu->dev); |
7519 | ret = dev_set_name(pmu->dev, "%s", pmu->name); | |
7520 | if (ret) | |
7521 | goto free_dev; | |
7522 | ||
7523 | dev_set_drvdata(pmu->dev, pmu); | |
7524 | pmu->dev->bus = &pmu_bus; | |
7525 | pmu->dev->release = pmu_dev_release; | |
7526 | ret = device_add(pmu->dev); | |
7527 | if (ret) | |
7528 | goto free_dev; | |
7529 | ||
7530 | out: | |
7531 | return ret; | |
7532 | ||
7533 | free_dev: | |
7534 | put_device(pmu->dev); | |
7535 | goto out; | |
7536 | } | |
7537 | ||
547e9fd7 | 7538 | static struct lock_class_key cpuctx_mutex; |
facc4307 | 7539 | static struct lock_class_key cpuctx_lock; |
547e9fd7 | 7540 | |
03d8e80b | 7541 | int perf_pmu_register(struct pmu *pmu, const char *name, int type) |
24f1e32c | 7542 | { |
108b02cf | 7543 | int cpu, ret; |
24f1e32c | 7544 | |
b0a873eb | 7545 | mutex_lock(&pmus_lock); |
33696fc0 PZ |
7546 | ret = -ENOMEM; |
7547 | pmu->pmu_disable_count = alloc_percpu(int); | |
7548 | if (!pmu->pmu_disable_count) | |
7549 | goto unlock; | |
f29ac756 | 7550 | |
2e80a82a PZ |
7551 | pmu->type = -1; |
7552 | if (!name) | |
7553 | goto skip_type; | |
7554 | pmu->name = name; | |
7555 | ||
7556 | if (type < 0) { | |
0e9c3be2 TH |
7557 | type = idr_alloc(&pmu_idr, pmu, PERF_TYPE_MAX, 0, GFP_KERNEL); |
7558 | if (type < 0) { | |
7559 | ret = type; | |
2e80a82a PZ |
7560 | goto free_pdc; |
7561 | } | |
7562 | } | |
7563 | pmu->type = type; | |
7564 | ||
abe43400 PZ |
7565 | if (pmu_bus_running) { |
7566 | ret = pmu_dev_alloc(pmu); | |
7567 | if (ret) | |
7568 | goto free_idr; | |
7569 | } | |
7570 | ||
2e80a82a | 7571 | skip_type: |
8dc85d54 PZ |
7572 | pmu->pmu_cpu_context = find_pmu_context(pmu->task_ctx_nr); |
7573 | if (pmu->pmu_cpu_context) | |
7574 | goto got_cpu_context; | |
f29ac756 | 7575 | |
c4814202 | 7576 | ret = -ENOMEM; |
108b02cf PZ |
7577 | pmu->pmu_cpu_context = alloc_percpu(struct perf_cpu_context); |
7578 | if (!pmu->pmu_cpu_context) | |
abe43400 | 7579 | goto free_dev; |
f344011c | 7580 | |
108b02cf PZ |
7581 | for_each_possible_cpu(cpu) { |
7582 | struct perf_cpu_context *cpuctx; | |
7583 | ||
7584 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
eb184479 | 7585 | __perf_event_init_context(&cpuctx->ctx); |
547e9fd7 | 7586 | lockdep_set_class(&cpuctx->ctx.mutex, &cpuctx_mutex); |
facc4307 | 7587 | lockdep_set_class(&cpuctx->ctx.lock, &cpuctx_lock); |
108b02cf | 7588 | cpuctx->ctx.pmu = pmu; |
9e630205 | 7589 | |
272325c4 | 7590 | __perf_mux_hrtimer_init(cpuctx, cpu); |
9e630205 | 7591 | |
3f1f3320 | 7592 | cpuctx->unique_pmu = pmu; |
108b02cf | 7593 | } |
76e1d904 | 7594 | |
8dc85d54 | 7595 | got_cpu_context: |
ad5133b7 PZ |
7596 | if (!pmu->start_txn) { |
7597 | if (pmu->pmu_enable) { | |
7598 | /* | |
7599 | * If we have pmu_enable/pmu_disable calls, install | |
7600 | * transaction stubs that use that to try and batch | |
7601 | * hardware accesses. | |
7602 | */ | |
7603 | pmu->start_txn = perf_pmu_start_txn; | |
7604 | pmu->commit_txn = perf_pmu_commit_txn; | |
7605 | pmu->cancel_txn = perf_pmu_cancel_txn; | |
7606 | } else { | |
fbbe0701 | 7607 | pmu->start_txn = perf_pmu_nop_txn; |
ad5133b7 PZ |
7608 | pmu->commit_txn = perf_pmu_nop_int; |
7609 | pmu->cancel_txn = perf_pmu_nop_void; | |
f344011c | 7610 | } |
5c92d124 | 7611 | } |
15dbf27c | 7612 | |
ad5133b7 PZ |
7613 | if (!pmu->pmu_enable) { |
7614 | pmu->pmu_enable = perf_pmu_nop_void; | |
7615 | pmu->pmu_disable = perf_pmu_nop_void; | |
7616 | } | |
7617 | ||
35edc2a5 PZ |
7618 | if (!pmu->event_idx) |
7619 | pmu->event_idx = perf_event_idx_default; | |
7620 | ||
b0a873eb | 7621 | list_add_rcu(&pmu->entry, &pmus); |
bed5b25a | 7622 | atomic_set(&pmu->exclusive_cnt, 0); |
33696fc0 PZ |
7623 | ret = 0; |
7624 | unlock: | |
b0a873eb PZ |
7625 | mutex_unlock(&pmus_lock); |
7626 | ||
33696fc0 | 7627 | return ret; |
108b02cf | 7628 | |
abe43400 PZ |
7629 | free_dev: |
7630 | device_del(pmu->dev); | |
7631 | put_device(pmu->dev); | |
7632 | ||
2e80a82a PZ |
7633 | free_idr: |
7634 | if (pmu->type >= PERF_TYPE_MAX) | |
7635 | idr_remove(&pmu_idr, pmu->type); | |
7636 | ||
108b02cf PZ |
7637 | free_pdc: |
7638 | free_percpu(pmu->pmu_disable_count); | |
7639 | goto unlock; | |
f29ac756 | 7640 | } |
c464c76e | 7641 | EXPORT_SYMBOL_GPL(perf_pmu_register); |
f29ac756 | 7642 | |
b0a873eb | 7643 | void perf_pmu_unregister(struct pmu *pmu) |
5c92d124 | 7644 | { |
b0a873eb PZ |
7645 | mutex_lock(&pmus_lock); |
7646 | list_del_rcu(&pmu->entry); | |
7647 | mutex_unlock(&pmus_lock); | |
5c92d124 | 7648 | |
0475f9ea | 7649 | /* |
cde8e884 PZ |
7650 | * We dereference the pmu list under both SRCU and regular RCU, so |
7651 | * synchronize against both of those. | |
0475f9ea | 7652 | */ |
b0a873eb | 7653 | synchronize_srcu(&pmus_srcu); |
cde8e884 | 7654 | synchronize_rcu(); |
d6d020e9 | 7655 | |
33696fc0 | 7656 | free_percpu(pmu->pmu_disable_count); |
2e80a82a PZ |
7657 | if (pmu->type >= PERF_TYPE_MAX) |
7658 | idr_remove(&pmu_idr, pmu->type); | |
abe43400 PZ |
7659 | device_del(pmu->dev); |
7660 | put_device(pmu->dev); | |
51676957 | 7661 | free_pmu_context(pmu); |
b0a873eb | 7662 | } |
c464c76e | 7663 | EXPORT_SYMBOL_GPL(perf_pmu_unregister); |
d6d020e9 | 7664 | |
cc34b98b MR |
7665 | static int perf_try_init_event(struct pmu *pmu, struct perf_event *event) |
7666 | { | |
ccd41c86 | 7667 | struct perf_event_context *ctx = NULL; |
cc34b98b MR |
7668 | int ret; |
7669 | ||
7670 | if (!try_module_get(pmu->module)) | |
7671 | return -ENODEV; | |
ccd41c86 PZ |
7672 | |
7673 | if (event->group_leader != event) { | |
8b10c5e2 PZ |
7674 | /* |
7675 | * This ctx->mutex can nest when we're called through | |
7676 | * inheritance. See the perf_event_ctx_lock_nested() comment. | |
7677 | */ | |
7678 | ctx = perf_event_ctx_lock_nested(event->group_leader, | |
7679 | SINGLE_DEPTH_NESTING); | |
ccd41c86 PZ |
7680 | BUG_ON(!ctx); |
7681 | } | |
7682 | ||
cc34b98b MR |
7683 | event->pmu = pmu; |
7684 | ret = pmu->event_init(event); | |
ccd41c86 PZ |
7685 | |
7686 | if (ctx) | |
7687 | perf_event_ctx_unlock(event->group_leader, ctx); | |
7688 | ||
cc34b98b MR |
7689 | if (ret) |
7690 | module_put(pmu->module); | |
7691 | ||
7692 | return ret; | |
7693 | } | |
7694 | ||
18ab2cd3 | 7695 | static struct pmu *perf_init_event(struct perf_event *event) |
b0a873eb PZ |
7696 | { |
7697 | struct pmu *pmu = NULL; | |
7698 | int idx; | |
940c5b29 | 7699 | int ret; |
b0a873eb PZ |
7700 | |
7701 | idx = srcu_read_lock(&pmus_srcu); | |
2e80a82a PZ |
7702 | |
7703 | rcu_read_lock(); | |
7704 | pmu = idr_find(&pmu_idr, event->attr.type); | |
7705 | rcu_read_unlock(); | |
940c5b29 | 7706 | if (pmu) { |
cc34b98b | 7707 | ret = perf_try_init_event(pmu, event); |
940c5b29 LM |
7708 | if (ret) |
7709 | pmu = ERR_PTR(ret); | |
2e80a82a | 7710 | goto unlock; |
940c5b29 | 7711 | } |
2e80a82a | 7712 | |
b0a873eb | 7713 | list_for_each_entry_rcu(pmu, &pmus, entry) { |
cc34b98b | 7714 | ret = perf_try_init_event(pmu, event); |
b0a873eb | 7715 | if (!ret) |
e5f4d339 | 7716 | goto unlock; |
76e1d904 | 7717 | |
b0a873eb PZ |
7718 | if (ret != -ENOENT) { |
7719 | pmu = ERR_PTR(ret); | |
e5f4d339 | 7720 | goto unlock; |
f344011c | 7721 | } |
5c92d124 | 7722 | } |
e5f4d339 PZ |
7723 | pmu = ERR_PTR(-ENOENT); |
7724 | unlock: | |
b0a873eb | 7725 | srcu_read_unlock(&pmus_srcu, idx); |
15dbf27c | 7726 | |
4aeb0b42 | 7727 | return pmu; |
5c92d124 IM |
7728 | } |
7729 | ||
4beb31f3 FW |
7730 | static void account_event_cpu(struct perf_event *event, int cpu) |
7731 | { | |
7732 | if (event->parent) | |
7733 | return; | |
7734 | ||
4beb31f3 FW |
7735 | if (is_cgroup_event(event)) |
7736 | atomic_inc(&per_cpu(perf_cgroup_events, cpu)); | |
7737 | } | |
7738 | ||
766d6c07 FW |
7739 | static void account_event(struct perf_event *event) |
7740 | { | |
4beb31f3 FW |
7741 | if (event->parent) |
7742 | return; | |
7743 | ||
766d6c07 FW |
7744 | if (event->attach_state & PERF_ATTACH_TASK) |
7745 | static_key_slow_inc(&perf_sched_events.key); | |
7746 | if (event->attr.mmap || event->attr.mmap_data) | |
7747 | atomic_inc(&nr_mmap_events); | |
7748 | if (event->attr.comm) | |
7749 | atomic_inc(&nr_comm_events); | |
7750 | if (event->attr.task) | |
7751 | atomic_inc(&nr_task_events); | |
948b26b6 FW |
7752 | if (event->attr.freq) { |
7753 | if (atomic_inc_return(&nr_freq_events) == 1) | |
7754 | tick_nohz_full_kick_all(); | |
7755 | } | |
45ac1403 AH |
7756 | if (event->attr.context_switch) { |
7757 | atomic_inc(&nr_switch_events); | |
7758 | static_key_slow_inc(&perf_sched_events.key); | |
7759 | } | |
4beb31f3 | 7760 | if (has_branch_stack(event)) |
766d6c07 | 7761 | static_key_slow_inc(&perf_sched_events.key); |
4beb31f3 | 7762 | if (is_cgroup_event(event)) |
766d6c07 | 7763 | static_key_slow_inc(&perf_sched_events.key); |
4beb31f3 FW |
7764 | |
7765 | account_event_cpu(event, event->cpu); | |
766d6c07 FW |
7766 | } |
7767 | ||
0793a61d | 7768 | /* |
cdd6c482 | 7769 | * Allocate and initialize a event structure |
0793a61d | 7770 | */ |
cdd6c482 | 7771 | static struct perf_event * |
c3f00c70 | 7772 | perf_event_alloc(struct perf_event_attr *attr, int cpu, |
d580ff86 PZ |
7773 | struct task_struct *task, |
7774 | struct perf_event *group_leader, | |
7775 | struct perf_event *parent_event, | |
4dc0da86 | 7776 | perf_overflow_handler_t overflow_handler, |
79dff51e | 7777 | void *context, int cgroup_fd) |
0793a61d | 7778 | { |
51b0fe39 | 7779 | struct pmu *pmu; |
cdd6c482 IM |
7780 | struct perf_event *event; |
7781 | struct hw_perf_event *hwc; | |
90983b16 | 7782 | long err = -EINVAL; |
0793a61d | 7783 | |
66832eb4 ON |
7784 | if ((unsigned)cpu >= nr_cpu_ids) { |
7785 | if (!task || cpu != -1) | |
7786 | return ERR_PTR(-EINVAL); | |
7787 | } | |
7788 | ||
c3f00c70 | 7789 | event = kzalloc(sizeof(*event), GFP_KERNEL); |
cdd6c482 | 7790 | if (!event) |
d5d2bc0d | 7791 | return ERR_PTR(-ENOMEM); |
0793a61d | 7792 | |
04289bb9 | 7793 | /* |
cdd6c482 | 7794 | * Single events are their own group leaders, with an |
04289bb9 IM |
7795 | * empty sibling list: |
7796 | */ | |
7797 | if (!group_leader) | |
cdd6c482 | 7798 | group_leader = event; |
04289bb9 | 7799 | |
cdd6c482 IM |
7800 | mutex_init(&event->child_mutex); |
7801 | INIT_LIST_HEAD(&event->child_list); | |
fccc714b | 7802 | |
cdd6c482 IM |
7803 | INIT_LIST_HEAD(&event->group_entry); |
7804 | INIT_LIST_HEAD(&event->event_entry); | |
7805 | INIT_LIST_HEAD(&event->sibling_list); | |
10c6db11 | 7806 | INIT_LIST_HEAD(&event->rb_entry); |
71ad88ef | 7807 | INIT_LIST_HEAD(&event->active_entry); |
f3ae75de SE |
7808 | INIT_HLIST_NODE(&event->hlist_entry); |
7809 | ||
10c6db11 | 7810 | |
cdd6c482 | 7811 | init_waitqueue_head(&event->waitq); |
e360adbe | 7812 | init_irq_work(&event->pending, perf_pending_event); |
0793a61d | 7813 | |
cdd6c482 | 7814 | mutex_init(&event->mmap_mutex); |
7b732a75 | 7815 | |
a6fa941d | 7816 | atomic_long_set(&event->refcount, 1); |
cdd6c482 IM |
7817 | event->cpu = cpu; |
7818 | event->attr = *attr; | |
7819 | event->group_leader = group_leader; | |
7820 | event->pmu = NULL; | |
cdd6c482 | 7821 | event->oncpu = -1; |
a96bbc16 | 7822 | |
cdd6c482 | 7823 | event->parent = parent_event; |
b84fbc9f | 7824 | |
17cf22c3 | 7825 | event->ns = get_pid_ns(task_active_pid_ns(current)); |
cdd6c482 | 7826 | event->id = atomic64_inc_return(&perf_event_id); |
a96bbc16 | 7827 | |
cdd6c482 | 7828 | event->state = PERF_EVENT_STATE_INACTIVE; |
329d876d | 7829 | |
d580ff86 PZ |
7830 | if (task) { |
7831 | event->attach_state = PERF_ATTACH_TASK; | |
d580ff86 | 7832 | /* |
50f16a8b PZ |
7833 | * XXX pmu::event_init needs to know what task to account to |
7834 | * and we cannot use the ctx information because we need the | |
7835 | * pmu before we get a ctx. | |
d580ff86 | 7836 | */ |
50f16a8b | 7837 | event->hw.target = task; |
d580ff86 PZ |
7838 | } |
7839 | ||
34f43927 PZ |
7840 | event->clock = &local_clock; |
7841 | if (parent_event) | |
7842 | event->clock = parent_event->clock; | |
7843 | ||
4dc0da86 | 7844 | if (!overflow_handler && parent_event) { |
b326e956 | 7845 | overflow_handler = parent_event->overflow_handler; |
4dc0da86 AK |
7846 | context = parent_event->overflow_handler_context; |
7847 | } | |
66832eb4 | 7848 | |
b326e956 | 7849 | event->overflow_handler = overflow_handler; |
4dc0da86 | 7850 | event->overflow_handler_context = context; |
97eaf530 | 7851 | |
0231bb53 | 7852 | perf_event__state_init(event); |
a86ed508 | 7853 | |
4aeb0b42 | 7854 | pmu = NULL; |
b8e83514 | 7855 | |
cdd6c482 | 7856 | hwc = &event->hw; |
bd2b5b12 | 7857 | hwc->sample_period = attr->sample_period; |
0d48696f | 7858 | if (attr->freq && attr->sample_freq) |
bd2b5b12 | 7859 | hwc->sample_period = 1; |
eced1dfc | 7860 | hwc->last_period = hwc->sample_period; |
bd2b5b12 | 7861 | |
e7850595 | 7862 | local64_set(&hwc->period_left, hwc->sample_period); |
60db5e09 | 7863 | |
2023b359 | 7864 | /* |
cdd6c482 | 7865 | * we currently do not support PERF_FORMAT_GROUP on inherited events |
2023b359 | 7866 | */ |
3dab77fb | 7867 | if (attr->inherit && (attr->read_format & PERF_FORMAT_GROUP)) |
90983b16 | 7868 | goto err_ns; |
a46a2300 YZ |
7869 | |
7870 | if (!has_branch_stack(event)) | |
7871 | event->attr.branch_sample_type = 0; | |
2023b359 | 7872 | |
79dff51e MF |
7873 | if (cgroup_fd != -1) { |
7874 | err = perf_cgroup_connect(cgroup_fd, event, attr, group_leader); | |
7875 | if (err) | |
7876 | goto err_ns; | |
7877 | } | |
7878 | ||
b0a873eb | 7879 | pmu = perf_init_event(event); |
4aeb0b42 | 7880 | if (!pmu) |
90983b16 FW |
7881 | goto err_ns; |
7882 | else if (IS_ERR(pmu)) { | |
4aeb0b42 | 7883 | err = PTR_ERR(pmu); |
90983b16 | 7884 | goto err_ns; |
621a01ea | 7885 | } |
d5d2bc0d | 7886 | |
bed5b25a AS |
7887 | err = exclusive_event_init(event); |
7888 | if (err) | |
7889 | goto err_pmu; | |
7890 | ||
cdd6c482 | 7891 | if (!event->parent) { |
927c7a9e FW |
7892 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) { |
7893 | err = get_callchain_buffers(); | |
90983b16 | 7894 | if (err) |
bed5b25a | 7895 | goto err_per_task; |
d010b332 | 7896 | } |
f344011c | 7897 | } |
9ee318a7 | 7898 | |
cdd6c482 | 7899 | return event; |
90983b16 | 7900 | |
bed5b25a AS |
7901 | err_per_task: |
7902 | exclusive_event_destroy(event); | |
7903 | ||
90983b16 FW |
7904 | err_pmu: |
7905 | if (event->destroy) | |
7906 | event->destroy(event); | |
c464c76e | 7907 | module_put(pmu->module); |
90983b16 | 7908 | err_ns: |
79dff51e MF |
7909 | if (is_cgroup_event(event)) |
7910 | perf_detach_cgroup(event); | |
90983b16 FW |
7911 | if (event->ns) |
7912 | put_pid_ns(event->ns); | |
7913 | kfree(event); | |
7914 | ||
7915 | return ERR_PTR(err); | |
0793a61d TG |
7916 | } |
7917 | ||
cdd6c482 IM |
7918 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
7919 | struct perf_event_attr *attr) | |
974802ea | 7920 | { |
974802ea | 7921 | u32 size; |
cdf8073d | 7922 | int ret; |
974802ea PZ |
7923 | |
7924 | if (!access_ok(VERIFY_WRITE, uattr, PERF_ATTR_SIZE_VER0)) | |
7925 | return -EFAULT; | |
7926 | ||
7927 | /* | |
7928 | * zero the full structure, so that a short copy will be nice. | |
7929 | */ | |
7930 | memset(attr, 0, sizeof(*attr)); | |
7931 | ||
7932 | ret = get_user(size, &uattr->size); | |
7933 | if (ret) | |
7934 | return ret; | |
7935 | ||
7936 | if (size > PAGE_SIZE) /* silly large */ | |
7937 | goto err_size; | |
7938 | ||
7939 | if (!size) /* abi compat */ | |
7940 | size = PERF_ATTR_SIZE_VER0; | |
7941 | ||
7942 | if (size < PERF_ATTR_SIZE_VER0) | |
7943 | goto err_size; | |
7944 | ||
7945 | /* | |
7946 | * If we're handed a bigger struct than we know of, | |
cdf8073d IS |
7947 | * ensure all the unknown bits are 0 - i.e. new |
7948 | * user-space does not rely on any kernel feature | |
7949 | * extensions we dont know about yet. | |
974802ea PZ |
7950 | */ |
7951 | if (size > sizeof(*attr)) { | |
cdf8073d IS |
7952 | unsigned char __user *addr; |
7953 | unsigned char __user *end; | |
7954 | unsigned char val; | |
974802ea | 7955 | |
cdf8073d IS |
7956 | addr = (void __user *)uattr + sizeof(*attr); |
7957 | end = (void __user *)uattr + size; | |
974802ea | 7958 | |
cdf8073d | 7959 | for (; addr < end; addr++) { |
974802ea PZ |
7960 | ret = get_user(val, addr); |
7961 | if (ret) | |
7962 | return ret; | |
7963 | if (val) | |
7964 | goto err_size; | |
7965 | } | |
b3e62e35 | 7966 | size = sizeof(*attr); |
974802ea PZ |
7967 | } |
7968 | ||
7969 | ret = copy_from_user(attr, uattr, size); | |
7970 | if (ret) | |
7971 | return -EFAULT; | |
7972 | ||
cd757645 | 7973 | if (attr->__reserved_1) |
974802ea PZ |
7974 | return -EINVAL; |
7975 | ||
7976 | if (attr->sample_type & ~(PERF_SAMPLE_MAX-1)) | |
7977 | return -EINVAL; | |
7978 | ||
7979 | if (attr->read_format & ~(PERF_FORMAT_MAX-1)) | |
7980 | return -EINVAL; | |
7981 | ||
bce38cd5 SE |
7982 | if (attr->sample_type & PERF_SAMPLE_BRANCH_STACK) { |
7983 | u64 mask = attr->branch_sample_type; | |
7984 | ||
7985 | /* only using defined bits */ | |
7986 | if (mask & ~(PERF_SAMPLE_BRANCH_MAX-1)) | |
7987 | return -EINVAL; | |
7988 | ||
7989 | /* at least one branch bit must be set */ | |
7990 | if (!(mask & ~PERF_SAMPLE_BRANCH_PLM_ALL)) | |
7991 | return -EINVAL; | |
7992 | ||
bce38cd5 SE |
7993 | /* propagate priv level, when not set for branch */ |
7994 | if (!(mask & PERF_SAMPLE_BRANCH_PLM_ALL)) { | |
7995 | ||
7996 | /* exclude_kernel checked on syscall entry */ | |
7997 | if (!attr->exclude_kernel) | |
7998 | mask |= PERF_SAMPLE_BRANCH_KERNEL; | |
7999 | ||
8000 | if (!attr->exclude_user) | |
8001 | mask |= PERF_SAMPLE_BRANCH_USER; | |
8002 | ||
8003 | if (!attr->exclude_hv) | |
8004 | mask |= PERF_SAMPLE_BRANCH_HV; | |
8005 | /* | |
8006 | * adjust user setting (for HW filter setup) | |
8007 | */ | |
8008 | attr->branch_sample_type = mask; | |
8009 | } | |
e712209a SE |
8010 | /* privileged levels capture (kernel, hv): check permissions */ |
8011 | if ((mask & PERF_SAMPLE_BRANCH_PERM_PLM) | |
2b923c8f SE |
8012 | && perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) |
8013 | return -EACCES; | |
bce38cd5 | 8014 | } |
4018994f | 8015 | |
c5ebcedb | 8016 | if (attr->sample_type & PERF_SAMPLE_REGS_USER) { |
4018994f | 8017 | ret = perf_reg_validate(attr->sample_regs_user); |
c5ebcedb JO |
8018 | if (ret) |
8019 | return ret; | |
8020 | } | |
8021 | ||
8022 | if (attr->sample_type & PERF_SAMPLE_STACK_USER) { | |
8023 | if (!arch_perf_have_user_stack_dump()) | |
8024 | return -ENOSYS; | |
8025 | ||
8026 | /* | |
8027 | * We have __u32 type for the size, but so far | |
8028 | * we can only use __u16 as maximum due to the | |
8029 | * __u16 sample size limit. | |
8030 | */ | |
8031 | if (attr->sample_stack_user >= USHRT_MAX) | |
8032 | ret = -EINVAL; | |
8033 | else if (!IS_ALIGNED(attr->sample_stack_user, sizeof(u64))) | |
8034 | ret = -EINVAL; | |
8035 | } | |
4018994f | 8036 | |
60e2364e SE |
8037 | if (attr->sample_type & PERF_SAMPLE_REGS_INTR) |
8038 | ret = perf_reg_validate(attr->sample_regs_intr); | |
974802ea PZ |
8039 | out: |
8040 | return ret; | |
8041 | ||
8042 | err_size: | |
8043 | put_user(sizeof(*attr), &uattr->size); | |
8044 | ret = -E2BIG; | |
8045 | goto out; | |
8046 | } | |
8047 | ||
ac9721f3 PZ |
8048 | static int |
8049 | perf_event_set_output(struct perf_event *event, struct perf_event *output_event) | |
a4be7c27 | 8050 | { |
b69cf536 | 8051 | struct ring_buffer *rb = NULL; |
a4be7c27 PZ |
8052 | int ret = -EINVAL; |
8053 | ||
ac9721f3 | 8054 | if (!output_event) |
a4be7c27 PZ |
8055 | goto set; |
8056 | ||
ac9721f3 PZ |
8057 | /* don't allow circular references */ |
8058 | if (event == output_event) | |
a4be7c27 PZ |
8059 | goto out; |
8060 | ||
0f139300 PZ |
8061 | /* |
8062 | * Don't allow cross-cpu buffers | |
8063 | */ | |
8064 | if (output_event->cpu != event->cpu) | |
8065 | goto out; | |
8066 | ||
8067 | /* | |
76369139 | 8068 | * If its not a per-cpu rb, it must be the same task. |
0f139300 PZ |
8069 | */ |
8070 | if (output_event->cpu == -1 && output_event->ctx != event->ctx) | |
8071 | goto out; | |
8072 | ||
34f43927 PZ |
8073 | /* |
8074 | * Mixing clocks in the same buffer is trouble you don't need. | |
8075 | */ | |
8076 | if (output_event->clock != event->clock) | |
8077 | goto out; | |
8078 | ||
45bfb2e5 PZ |
8079 | /* |
8080 | * If both events generate aux data, they must be on the same PMU | |
8081 | */ | |
8082 | if (has_aux(event) && has_aux(output_event) && | |
8083 | event->pmu != output_event->pmu) | |
8084 | goto out; | |
8085 | ||
a4be7c27 | 8086 | set: |
cdd6c482 | 8087 | mutex_lock(&event->mmap_mutex); |
ac9721f3 PZ |
8088 | /* Can't redirect output if we've got an active mmap() */ |
8089 | if (atomic_read(&event->mmap_count)) | |
8090 | goto unlock; | |
a4be7c27 | 8091 | |
ac9721f3 | 8092 | if (output_event) { |
76369139 FW |
8093 | /* get the rb we want to redirect to */ |
8094 | rb = ring_buffer_get(output_event); | |
8095 | if (!rb) | |
ac9721f3 | 8096 | goto unlock; |
a4be7c27 PZ |
8097 | } |
8098 | ||
b69cf536 | 8099 | ring_buffer_attach(event, rb); |
9bb5d40c | 8100 | |
a4be7c27 | 8101 | ret = 0; |
ac9721f3 PZ |
8102 | unlock: |
8103 | mutex_unlock(&event->mmap_mutex); | |
8104 | ||
a4be7c27 | 8105 | out: |
a4be7c27 PZ |
8106 | return ret; |
8107 | } | |
8108 | ||
f63a8daa PZ |
8109 | static void mutex_lock_double(struct mutex *a, struct mutex *b) |
8110 | { | |
8111 | if (b < a) | |
8112 | swap(a, b); | |
8113 | ||
8114 | mutex_lock(a); | |
8115 | mutex_lock_nested(b, SINGLE_DEPTH_NESTING); | |
8116 | } | |
8117 | ||
34f43927 PZ |
8118 | static int perf_event_set_clock(struct perf_event *event, clockid_t clk_id) |
8119 | { | |
8120 | bool nmi_safe = false; | |
8121 | ||
8122 | switch (clk_id) { | |
8123 | case CLOCK_MONOTONIC: | |
8124 | event->clock = &ktime_get_mono_fast_ns; | |
8125 | nmi_safe = true; | |
8126 | break; | |
8127 | ||
8128 | case CLOCK_MONOTONIC_RAW: | |
8129 | event->clock = &ktime_get_raw_fast_ns; | |
8130 | nmi_safe = true; | |
8131 | break; | |
8132 | ||
8133 | case CLOCK_REALTIME: | |
8134 | event->clock = &ktime_get_real_ns; | |
8135 | break; | |
8136 | ||
8137 | case CLOCK_BOOTTIME: | |
8138 | event->clock = &ktime_get_boot_ns; | |
8139 | break; | |
8140 | ||
8141 | case CLOCK_TAI: | |
8142 | event->clock = &ktime_get_tai_ns; | |
8143 | break; | |
8144 | ||
8145 | default: | |
8146 | return -EINVAL; | |
8147 | } | |
8148 | ||
8149 | if (!nmi_safe && !(event->pmu->capabilities & PERF_PMU_CAP_NO_NMI)) | |
8150 | return -EINVAL; | |
8151 | ||
8152 | return 0; | |
8153 | } | |
8154 | ||
0793a61d | 8155 | /** |
cdd6c482 | 8156 | * sys_perf_event_open - open a performance event, associate it to a task/cpu |
9f66a381 | 8157 | * |
cdd6c482 | 8158 | * @attr_uptr: event_id type attributes for monitoring/sampling |
0793a61d | 8159 | * @pid: target pid |
9f66a381 | 8160 | * @cpu: target cpu |
cdd6c482 | 8161 | * @group_fd: group leader event fd |
0793a61d | 8162 | */ |
cdd6c482 IM |
8163 | SYSCALL_DEFINE5(perf_event_open, |
8164 | struct perf_event_attr __user *, attr_uptr, | |
2743a5b0 | 8165 | pid_t, pid, int, cpu, int, group_fd, unsigned long, flags) |
0793a61d | 8166 | { |
b04243ef PZ |
8167 | struct perf_event *group_leader = NULL, *output_event = NULL; |
8168 | struct perf_event *event, *sibling; | |
cdd6c482 | 8169 | struct perf_event_attr attr; |
f63a8daa | 8170 | struct perf_event_context *ctx, *uninitialized_var(gctx); |
cdd6c482 | 8171 | struct file *event_file = NULL; |
2903ff01 | 8172 | struct fd group = {NULL, 0}; |
38a81da2 | 8173 | struct task_struct *task = NULL; |
89a1e187 | 8174 | struct pmu *pmu; |
ea635c64 | 8175 | int event_fd; |
b04243ef | 8176 | int move_group = 0; |
dc86cabe | 8177 | int err; |
a21b0b35 | 8178 | int f_flags = O_RDWR; |
79dff51e | 8179 | int cgroup_fd = -1; |
0793a61d | 8180 | |
2743a5b0 | 8181 | /* for future expandability... */ |
e5d1367f | 8182 | if (flags & ~PERF_FLAG_ALL) |
2743a5b0 PM |
8183 | return -EINVAL; |
8184 | ||
dc86cabe IM |
8185 | err = perf_copy_attr(attr_uptr, &attr); |
8186 | if (err) | |
8187 | return err; | |
eab656ae | 8188 | |
0764771d PZ |
8189 | if (!attr.exclude_kernel) { |
8190 | if (perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) | |
8191 | return -EACCES; | |
8192 | } | |
8193 | ||
df58ab24 | 8194 | if (attr.freq) { |
cdd6c482 | 8195 | if (attr.sample_freq > sysctl_perf_event_sample_rate) |
df58ab24 | 8196 | return -EINVAL; |
0819b2e3 PZ |
8197 | } else { |
8198 | if (attr.sample_period & (1ULL << 63)) | |
8199 | return -EINVAL; | |
df58ab24 PZ |
8200 | } |
8201 | ||
e5d1367f SE |
8202 | /* |
8203 | * In cgroup mode, the pid argument is used to pass the fd | |
8204 | * opened to the cgroup directory in cgroupfs. The cpu argument | |
8205 | * designates the cpu on which to monitor threads from that | |
8206 | * cgroup. | |
8207 | */ | |
8208 | if ((flags & PERF_FLAG_PID_CGROUP) && (pid == -1 || cpu == -1)) | |
8209 | return -EINVAL; | |
8210 | ||
a21b0b35 YD |
8211 | if (flags & PERF_FLAG_FD_CLOEXEC) |
8212 | f_flags |= O_CLOEXEC; | |
8213 | ||
8214 | event_fd = get_unused_fd_flags(f_flags); | |
ea635c64 AV |
8215 | if (event_fd < 0) |
8216 | return event_fd; | |
8217 | ||
ac9721f3 | 8218 | if (group_fd != -1) { |
2903ff01 AV |
8219 | err = perf_fget_light(group_fd, &group); |
8220 | if (err) | |
d14b12d7 | 8221 | goto err_fd; |
2903ff01 | 8222 | group_leader = group.file->private_data; |
ac9721f3 PZ |
8223 | if (flags & PERF_FLAG_FD_OUTPUT) |
8224 | output_event = group_leader; | |
8225 | if (flags & PERF_FLAG_FD_NO_GROUP) | |
8226 | group_leader = NULL; | |
8227 | } | |
8228 | ||
e5d1367f | 8229 | if (pid != -1 && !(flags & PERF_FLAG_PID_CGROUP)) { |
c6be5a5c PZ |
8230 | task = find_lively_task_by_vpid(pid); |
8231 | if (IS_ERR(task)) { | |
8232 | err = PTR_ERR(task); | |
8233 | goto err_group_fd; | |
8234 | } | |
8235 | } | |
8236 | ||
1f4ee503 PZ |
8237 | if (task && group_leader && |
8238 | group_leader->attr.inherit != attr.inherit) { | |
8239 | err = -EINVAL; | |
8240 | goto err_task; | |
8241 | } | |
8242 | ||
fbfc623f YZ |
8243 | get_online_cpus(); |
8244 | ||
79dff51e MF |
8245 | if (flags & PERF_FLAG_PID_CGROUP) |
8246 | cgroup_fd = pid; | |
8247 | ||
4dc0da86 | 8248 | event = perf_event_alloc(&attr, cpu, task, group_leader, NULL, |
79dff51e | 8249 | NULL, NULL, cgroup_fd); |
d14b12d7 SE |
8250 | if (IS_ERR(event)) { |
8251 | err = PTR_ERR(event); | |
1f4ee503 | 8252 | goto err_cpus; |
d14b12d7 SE |
8253 | } |
8254 | ||
53b25335 VW |
8255 | if (is_sampling_event(event)) { |
8256 | if (event->pmu->capabilities & PERF_PMU_CAP_NO_INTERRUPT) { | |
8257 | err = -ENOTSUPP; | |
8258 | goto err_alloc; | |
8259 | } | |
8260 | } | |
8261 | ||
766d6c07 FW |
8262 | account_event(event); |
8263 | ||
89a1e187 PZ |
8264 | /* |
8265 | * Special case software events and allow them to be part of | |
8266 | * any hardware group. | |
8267 | */ | |
8268 | pmu = event->pmu; | |
b04243ef | 8269 | |
34f43927 PZ |
8270 | if (attr.use_clockid) { |
8271 | err = perf_event_set_clock(event, attr.clockid); | |
8272 | if (err) | |
8273 | goto err_alloc; | |
8274 | } | |
8275 | ||
b04243ef PZ |
8276 | if (group_leader && |
8277 | (is_software_event(event) != is_software_event(group_leader))) { | |
8278 | if (is_software_event(event)) { | |
8279 | /* | |
8280 | * If event and group_leader are not both a software | |
8281 | * event, and event is, then group leader is not. | |
8282 | * | |
8283 | * Allow the addition of software events to !software | |
8284 | * groups, this is safe because software events never | |
8285 | * fail to schedule. | |
8286 | */ | |
8287 | pmu = group_leader->pmu; | |
8288 | } else if (is_software_event(group_leader) && | |
8289 | (group_leader->group_flags & PERF_GROUP_SOFTWARE)) { | |
8290 | /* | |
8291 | * In case the group is a pure software group, and we | |
8292 | * try to add a hardware event, move the whole group to | |
8293 | * the hardware context. | |
8294 | */ | |
8295 | move_group = 1; | |
8296 | } | |
8297 | } | |
89a1e187 PZ |
8298 | |
8299 | /* | |
8300 | * Get the target context (task or percpu): | |
8301 | */ | |
4af57ef2 | 8302 | ctx = find_get_context(pmu, task, event); |
89a1e187 PZ |
8303 | if (IS_ERR(ctx)) { |
8304 | err = PTR_ERR(ctx); | |
c6be5a5c | 8305 | goto err_alloc; |
89a1e187 PZ |
8306 | } |
8307 | ||
bed5b25a AS |
8308 | if ((pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE) && group_leader) { |
8309 | err = -EBUSY; | |
8310 | goto err_context; | |
8311 | } | |
8312 | ||
fd1edb3a PZ |
8313 | if (task) { |
8314 | put_task_struct(task); | |
8315 | task = NULL; | |
8316 | } | |
8317 | ||
ccff286d | 8318 | /* |
cdd6c482 | 8319 | * Look up the group leader (we will attach this event to it): |
04289bb9 | 8320 | */ |
ac9721f3 | 8321 | if (group_leader) { |
dc86cabe | 8322 | err = -EINVAL; |
04289bb9 | 8323 | |
04289bb9 | 8324 | /* |
ccff286d IM |
8325 | * Do not allow a recursive hierarchy (this new sibling |
8326 | * becoming part of another group-sibling): | |
8327 | */ | |
8328 | if (group_leader->group_leader != group_leader) | |
c3f00c70 | 8329 | goto err_context; |
34f43927 PZ |
8330 | |
8331 | /* All events in a group should have the same clock */ | |
8332 | if (group_leader->clock != event->clock) | |
8333 | goto err_context; | |
8334 | ||
ccff286d IM |
8335 | /* |
8336 | * Do not allow to attach to a group in a different | |
8337 | * task or CPU context: | |
04289bb9 | 8338 | */ |
b04243ef | 8339 | if (move_group) { |
c3c87e77 PZ |
8340 | /* |
8341 | * Make sure we're both on the same task, or both | |
8342 | * per-cpu events. | |
8343 | */ | |
8344 | if (group_leader->ctx->task != ctx->task) | |
8345 | goto err_context; | |
8346 | ||
8347 | /* | |
8348 | * Make sure we're both events for the same CPU; | |
8349 | * grouping events for different CPUs is broken; since | |
8350 | * you can never concurrently schedule them anyhow. | |
8351 | */ | |
8352 | if (group_leader->cpu != event->cpu) | |
b04243ef PZ |
8353 | goto err_context; |
8354 | } else { | |
8355 | if (group_leader->ctx != ctx) | |
8356 | goto err_context; | |
8357 | } | |
8358 | ||
3b6f9e5c PM |
8359 | /* |
8360 | * Only a group leader can be exclusive or pinned | |
8361 | */ | |
0d48696f | 8362 | if (attr.exclusive || attr.pinned) |
c3f00c70 | 8363 | goto err_context; |
ac9721f3 PZ |
8364 | } |
8365 | ||
8366 | if (output_event) { | |
8367 | err = perf_event_set_output(event, output_event); | |
8368 | if (err) | |
c3f00c70 | 8369 | goto err_context; |
ac9721f3 | 8370 | } |
0793a61d | 8371 | |
a21b0b35 YD |
8372 | event_file = anon_inode_getfile("[perf_event]", &perf_fops, event, |
8373 | f_flags); | |
ea635c64 AV |
8374 | if (IS_ERR(event_file)) { |
8375 | err = PTR_ERR(event_file); | |
c3f00c70 | 8376 | goto err_context; |
ea635c64 | 8377 | } |
9b51f66d | 8378 | |
b04243ef | 8379 | if (move_group) { |
f63a8daa | 8380 | gctx = group_leader->ctx; |
f55fc2a5 PZ |
8381 | mutex_lock_double(&gctx->mutex, &ctx->mutex); |
8382 | } else { | |
8383 | mutex_lock(&ctx->mutex); | |
8384 | } | |
8385 | ||
a723968c PZ |
8386 | if (!perf_event_validate_size(event)) { |
8387 | err = -E2BIG; | |
8388 | goto err_locked; | |
8389 | } | |
8390 | ||
f55fc2a5 PZ |
8391 | /* |
8392 | * Must be under the same ctx::mutex as perf_install_in_context(), | |
8393 | * because we need to serialize with concurrent event creation. | |
8394 | */ | |
8395 | if (!exclusive_event_installable(event, ctx)) { | |
8396 | /* exclusive and group stuff are assumed mutually exclusive */ | |
8397 | WARN_ON_ONCE(move_group); | |
f63a8daa | 8398 | |
f55fc2a5 PZ |
8399 | err = -EBUSY; |
8400 | goto err_locked; | |
8401 | } | |
f63a8daa | 8402 | |
f55fc2a5 PZ |
8403 | WARN_ON_ONCE(ctx->parent_ctx); |
8404 | ||
8405 | if (move_group) { | |
f63a8daa PZ |
8406 | /* |
8407 | * See perf_event_ctx_lock() for comments on the details | |
8408 | * of swizzling perf_event::ctx. | |
8409 | */ | |
46ce0fe9 | 8410 | perf_remove_from_context(group_leader, false); |
0231bb53 | 8411 | |
b04243ef PZ |
8412 | list_for_each_entry(sibling, &group_leader->sibling_list, |
8413 | group_entry) { | |
46ce0fe9 | 8414 | perf_remove_from_context(sibling, false); |
b04243ef PZ |
8415 | put_ctx(gctx); |
8416 | } | |
b04243ef | 8417 | |
f63a8daa PZ |
8418 | /* |
8419 | * Wait for everybody to stop referencing the events through | |
8420 | * the old lists, before installing it on new lists. | |
8421 | */ | |
0cda4c02 | 8422 | synchronize_rcu(); |
f63a8daa | 8423 | |
8f95b435 PZI |
8424 | /* |
8425 | * Install the group siblings before the group leader. | |
8426 | * | |
8427 | * Because a group leader will try and install the entire group | |
8428 | * (through the sibling list, which is still in-tact), we can | |
8429 | * end up with siblings installed in the wrong context. | |
8430 | * | |
8431 | * By installing siblings first we NO-OP because they're not | |
8432 | * reachable through the group lists. | |
8433 | */ | |
b04243ef PZ |
8434 | list_for_each_entry(sibling, &group_leader->sibling_list, |
8435 | group_entry) { | |
8f95b435 | 8436 | perf_event__state_init(sibling); |
9fc81d87 | 8437 | perf_install_in_context(ctx, sibling, sibling->cpu); |
b04243ef PZ |
8438 | get_ctx(ctx); |
8439 | } | |
8f95b435 PZI |
8440 | |
8441 | /* | |
8442 | * Removing from the context ends up with disabled | |
8443 | * event. What we want here is event in the initial | |
8444 | * startup state, ready to be add into new context. | |
8445 | */ | |
8446 | perf_event__state_init(group_leader); | |
8447 | perf_install_in_context(ctx, group_leader, group_leader->cpu); | |
8448 | get_ctx(ctx); | |
b04243ef | 8449 | |
f55fc2a5 PZ |
8450 | /* |
8451 | * Now that all events are installed in @ctx, nothing | |
8452 | * references @gctx anymore, so drop the last reference we have | |
8453 | * on it. | |
8454 | */ | |
8455 | put_ctx(gctx); | |
bed5b25a AS |
8456 | } |
8457 | ||
f73e22ab PZ |
8458 | /* |
8459 | * Precalculate sample_data sizes; do while holding ctx::mutex such | |
8460 | * that we're serialized against further additions and before | |
8461 | * perf_install_in_context() which is the point the event is active and | |
8462 | * can use these values. | |
8463 | */ | |
8464 | perf_event__header_size(event); | |
8465 | perf_event__id_header_size(event); | |
8466 | ||
e2d37cd2 | 8467 | perf_install_in_context(ctx, event, event->cpu); |
fe4b04fa | 8468 | perf_unpin_context(ctx); |
f63a8daa | 8469 | |
f55fc2a5 | 8470 | if (move_group) |
f63a8daa | 8471 | mutex_unlock(&gctx->mutex); |
d859e29f | 8472 | mutex_unlock(&ctx->mutex); |
9b51f66d | 8473 | |
fbfc623f YZ |
8474 | put_online_cpus(); |
8475 | ||
cdd6c482 | 8476 | event->owner = current; |
8882135b | 8477 | |
cdd6c482 IM |
8478 | mutex_lock(¤t->perf_event_mutex); |
8479 | list_add_tail(&event->owner_entry, ¤t->perf_event_list); | |
8480 | mutex_unlock(¤t->perf_event_mutex); | |
082ff5a2 | 8481 | |
8a49542c PZ |
8482 | /* |
8483 | * Drop the reference on the group_event after placing the | |
8484 | * new event on the sibling_list. This ensures destruction | |
8485 | * of the group leader will find the pointer to itself in | |
8486 | * perf_group_detach(). | |
8487 | */ | |
2903ff01 | 8488 | fdput(group); |
ea635c64 AV |
8489 | fd_install(event_fd, event_file); |
8490 | return event_fd; | |
0793a61d | 8491 | |
f55fc2a5 PZ |
8492 | err_locked: |
8493 | if (move_group) | |
8494 | mutex_unlock(&gctx->mutex); | |
8495 | mutex_unlock(&ctx->mutex); | |
8496 | /* err_file: */ | |
8497 | fput(event_file); | |
c3f00c70 | 8498 | err_context: |
fe4b04fa | 8499 | perf_unpin_context(ctx); |
ea635c64 | 8500 | put_ctx(ctx); |
c6be5a5c | 8501 | err_alloc: |
ea635c64 | 8502 | free_event(event); |
1f4ee503 | 8503 | err_cpus: |
fbfc623f | 8504 | put_online_cpus(); |
1f4ee503 | 8505 | err_task: |
e7d0bc04 PZ |
8506 | if (task) |
8507 | put_task_struct(task); | |
89a1e187 | 8508 | err_group_fd: |
2903ff01 | 8509 | fdput(group); |
ea635c64 AV |
8510 | err_fd: |
8511 | put_unused_fd(event_fd); | |
dc86cabe | 8512 | return err; |
0793a61d TG |
8513 | } |
8514 | ||
fb0459d7 AV |
8515 | /** |
8516 | * perf_event_create_kernel_counter | |
8517 | * | |
8518 | * @attr: attributes of the counter to create | |
8519 | * @cpu: cpu in which the counter is bound | |
38a81da2 | 8520 | * @task: task to profile (NULL for percpu) |
fb0459d7 AV |
8521 | */ |
8522 | struct perf_event * | |
8523 | perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, | |
38a81da2 | 8524 | struct task_struct *task, |
4dc0da86 AK |
8525 | perf_overflow_handler_t overflow_handler, |
8526 | void *context) | |
fb0459d7 | 8527 | { |
fb0459d7 | 8528 | struct perf_event_context *ctx; |
c3f00c70 | 8529 | struct perf_event *event; |
fb0459d7 | 8530 | int err; |
d859e29f | 8531 | |
fb0459d7 AV |
8532 | /* |
8533 | * Get the target context (task or percpu): | |
8534 | */ | |
d859e29f | 8535 | |
4dc0da86 | 8536 | event = perf_event_alloc(attr, cpu, task, NULL, NULL, |
79dff51e | 8537 | overflow_handler, context, -1); |
c3f00c70 PZ |
8538 | if (IS_ERR(event)) { |
8539 | err = PTR_ERR(event); | |
8540 | goto err; | |
8541 | } | |
d859e29f | 8542 | |
f8697762 JO |
8543 | /* Mark owner so we could distinguish it from user events. */ |
8544 | event->owner = EVENT_OWNER_KERNEL; | |
8545 | ||
766d6c07 FW |
8546 | account_event(event); |
8547 | ||
4af57ef2 | 8548 | ctx = find_get_context(event->pmu, task, event); |
c6567f64 FW |
8549 | if (IS_ERR(ctx)) { |
8550 | err = PTR_ERR(ctx); | |
c3f00c70 | 8551 | goto err_free; |
d859e29f | 8552 | } |
fb0459d7 | 8553 | |
fb0459d7 AV |
8554 | WARN_ON_ONCE(ctx->parent_ctx); |
8555 | mutex_lock(&ctx->mutex); | |
bed5b25a AS |
8556 | if (!exclusive_event_installable(event, ctx)) { |
8557 | mutex_unlock(&ctx->mutex); | |
8558 | perf_unpin_context(ctx); | |
8559 | put_ctx(ctx); | |
8560 | err = -EBUSY; | |
8561 | goto err_free; | |
8562 | } | |
8563 | ||
fb0459d7 | 8564 | perf_install_in_context(ctx, event, cpu); |
fe4b04fa | 8565 | perf_unpin_context(ctx); |
fb0459d7 AV |
8566 | mutex_unlock(&ctx->mutex); |
8567 | ||
fb0459d7 AV |
8568 | return event; |
8569 | ||
c3f00c70 PZ |
8570 | err_free: |
8571 | free_event(event); | |
8572 | err: | |
c6567f64 | 8573 | return ERR_PTR(err); |
9b51f66d | 8574 | } |
fb0459d7 | 8575 | EXPORT_SYMBOL_GPL(perf_event_create_kernel_counter); |
9b51f66d | 8576 | |
0cda4c02 YZ |
8577 | void perf_pmu_migrate_context(struct pmu *pmu, int src_cpu, int dst_cpu) |
8578 | { | |
8579 | struct perf_event_context *src_ctx; | |
8580 | struct perf_event_context *dst_ctx; | |
8581 | struct perf_event *event, *tmp; | |
8582 | LIST_HEAD(events); | |
8583 | ||
8584 | src_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, src_cpu)->ctx; | |
8585 | dst_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, dst_cpu)->ctx; | |
8586 | ||
f63a8daa PZ |
8587 | /* |
8588 | * See perf_event_ctx_lock() for comments on the details | |
8589 | * of swizzling perf_event::ctx. | |
8590 | */ | |
8591 | mutex_lock_double(&src_ctx->mutex, &dst_ctx->mutex); | |
0cda4c02 YZ |
8592 | list_for_each_entry_safe(event, tmp, &src_ctx->event_list, |
8593 | event_entry) { | |
46ce0fe9 | 8594 | perf_remove_from_context(event, false); |
9a545de0 | 8595 | unaccount_event_cpu(event, src_cpu); |
0cda4c02 | 8596 | put_ctx(src_ctx); |
9886167d | 8597 | list_add(&event->migrate_entry, &events); |
0cda4c02 | 8598 | } |
0cda4c02 | 8599 | |
8f95b435 PZI |
8600 | /* |
8601 | * Wait for the events to quiesce before re-instating them. | |
8602 | */ | |
0cda4c02 YZ |
8603 | synchronize_rcu(); |
8604 | ||
8f95b435 PZI |
8605 | /* |
8606 | * Re-instate events in 2 passes. | |
8607 | * | |
8608 | * Skip over group leaders and only install siblings on this first | |
8609 | * pass, siblings will not get enabled without a leader, however a | |
8610 | * leader will enable its siblings, even if those are still on the old | |
8611 | * context. | |
8612 | */ | |
8613 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { | |
8614 | if (event->group_leader == event) | |
8615 | continue; | |
8616 | ||
8617 | list_del(&event->migrate_entry); | |
8618 | if (event->state >= PERF_EVENT_STATE_OFF) | |
8619 | event->state = PERF_EVENT_STATE_INACTIVE; | |
8620 | account_event_cpu(event, dst_cpu); | |
8621 | perf_install_in_context(dst_ctx, event, dst_cpu); | |
8622 | get_ctx(dst_ctx); | |
8623 | } | |
8624 | ||
8625 | /* | |
8626 | * Once all the siblings are setup properly, install the group leaders | |
8627 | * to make it go. | |
8628 | */ | |
9886167d PZ |
8629 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { |
8630 | list_del(&event->migrate_entry); | |
0cda4c02 YZ |
8631 | if (event->state >= PERF_EVENT_STATE_OFF) |
8632 | event->state = PERF_EVENT_STATE_INACTIVE; | |
9a545de0 | 8633 | account_event_cpu(event, dst_cpu); |
0cda4c02 YZ |
8634 | perf_install_in_context(dst_ctx, event, dst_cpu); |
8635 | get_ctx(dst_ctx); | |
8636 | } | |
8637 | mutex_unlock(&dst_ctx->mutex); | |
f63a8daa | 8638 | mutex_unlock(&src_ctx->mutex); |
0cda4c02 YZ |
8639 | } |
8640 | EXPORT_SYMBOL_GPL(perf_pmu_migrate_context); | |
8641 | ||
cdd6c482 | 8642 | static void sync_child_event(struct perf_event *child_event, |
38b200d6 | 8643 | struct task_struct *child) |
d859e29f | 8644 | { |
cdd6c482 | 8645 | struct perf_event *parent_event = child_event->parent; |
8bc20959 | 8646 | u64 child_val; |
d859e29f | 8647 | |
cdd6c482 IM |
8648 | if (child_event->attr.inherit_stat) |
8649 | perf_event_read_event(child_event, child); | |
38b200d6 | 8650 | |
b5e58793 | 8651 | child_val = perf_event_count(child_event); |
d859e29f PM |
8652 | |
8653 | /* | |
8654 | * Add back the child's count to the parent's count: | |
8655 | */ | |
a6e6dea6 | 8656 | atomic64_add(child_val, &parent_event->child_count); |
cdd6c482 IM |
8657 | atomic64_add(child_event->total_time_enabled, |
8658 | &parent_event->child_total_time_enabled); | |
8659 | atomic64_add(child_event->total_time_running, | |
8660 | &parent_event->child_total_time_running); | |
d859e29f PM |
8661 | |
8662 | /* | |
cdd6c482 | 8663 | * Remove this event from the parent's list |
d859e29f | 8664 | */ |
cdd6c482 IM |
8665 | WARN_ON_ONCE(parent_event->ctx->parent_ctx); |
8666 | mutex_lock(&parent_event->child_mutex); | |
8667 | list_del_init(&child_event->child_list); | |
8668 | mutex_unlock(&parent_event->child_mutex); | |
d859e29f | 8669 | |
dc633982 JO |
8670 | /* |
8671 | * Make sure user/parent get notified, that we just | |
8672 | * lost one event. | |
8673 | */ | |
8674 | perf_event_wakeup(parent_event); | |
8675 | ||
d859e29f | 8676 | /* |
cdd6c482 | 8677 | * Release the parent event, if this was the last |
d859e29f PM |
8678 | * reference to it. |
8679 | */ | |
a6fa941d | 8680 | put_event(parent_event); |
d859e29f PM |
8681 | } |
8682 | ||
9b51f66d | 8683 | static void |
cdd6c482 IM |
8684 | __perf_event_exit_task(struct perf_event *child_event, |
8685 | struct perf_event_context *child_ctx, | |
38b200d6 | 8686 | struct task_struct *child) |
9b51f66d | 8687 | { |
1903d50c PZ |
8688 | /* |
8689 | * Do not destroy the 'original' grouping; because of the context | |
8690 | * switch optimization the original events could've ended up in a | |
8691 | * random child task. | |
8692 | * | |
8693 | * If we were to destroy the original group, all group related | |
8694 | * operations would cease to function properly after this random | |
8695 | * child dies. | |
8696 | * | |
8697 | * Do destroy all inherited groups, we don't care about those | |
8698 | * and being thorough is better. | |
8699 | */ | |
8700 | perf_remove_from_context(child_event, !!child_event->parent); | |
0cc0c027 | 8701 | |
9b51f66d | 8702 | /* |
38b435b1 | 8703 | * It can happen that the parent exits first, and has events |
9b51f66d | 8704 | * that are still around due to the child reference. These |
38b435b1 | 8705 | * events need to be zapped. |
9b51f66d | 8706 | */ |
38b435b1 | 8707 | if (child_event->parent) { |
cdd6c482 IM |
8708 | sync_child_event(child_event, child); |
8709 | free_event(child_event); | |
179033b3 JO |
8710 | } else { |
8711 | child_event->state = PERF_EVENT_STATE_EXIT; | |
8712 | perf_event_wakeup(child_event); | |
4bcf349a | 8713 | } |
9b51f66d IM |
8714 | } |
8715 | ||
8dc85d54 | 8716 | static void perf_event_exit_task_context(struct task_struct *child, int ctxn) |
9b51f66d | 8717 | { |
ebf905fc | 8718 | struct perf_event *child_event, *next; |
211de6eb | 8719 | struct perf_event_context *child_ctx, *clone_ctx = NULL; |
a63eaf34 | 8720 | unsigned long flags; |
9b51f66d | 8721 | |
4e93ad60 | 8722 | if (likely(!child->perf_event_ctxp[ctxn])) |
9b51f66d IM |
8723 | return; |
8724 | ||
a63eaf34 | 8725 | local_irq_save(flags); |
ad3a37de PM |
8726 | /* |
8727 | * We can't reschedule here because interrupts are disabled, | |
8728 | * and either child is current or it is a task that can't be | |
8729 | * scheduled, so we are now safe from rescheduling changing | |
8730 | * our context. | |
8731 | */ | |
806839b2 | 8732 | child_ctx = rcu_dereference_raw(child->perf_event_ctxp[ctxn]); |
c93f7669 PM |
8733 | |
8734 | /* | |
8735 | * Take the context lock here so that if find_get_context is | |
cdd6c482 | 8736 | * reading child->perf_event_ctxp, we wait until it has |
c93f7669 PM |
8737 | * incremented the context's refcount before we do put_ctx below. |
8738 | */ | |
e625cce1 | 8739 | raw_spin_lock(&child_ctx->lock); |
04dc2dbb | 8740 | task_ctx_sched_out(child_ctx); |
8dc85d54 | 8741 | child->perf_event_ctxp[ctxn] = NULL; |
4a1c0f26 | 8742 | |
71a851b4 PZ |
8743 | /* |
8744 | * If this context is a clone; unclone it so it can't get | |
8745 | * swapped to another process while we're removing all | |
cdd6c482 | 8746 | * the events from it. |
71a851b4 | 8747 | */ |
211de6eb | 8748 | clone_ctx = unclone_ctx(child_ctx); |
5e942bb3 | 8749 | update_context_time(child_ctx); |
e625cce1 | 8750 | raw_spin_unlock_irqrestore(&child_ctx->lock, flags); |
9f498cc5 | 8751 | |
211de6eb PZ |
8752 | if (clone_ctx) |
8753 | put_ctx(clone_ctx); | |
4a1c0f26 | 8754 | |
9f498cc5 | 8755 | /* |
cdd6c482 IM |
8756 | * Report the task dead after unscheduling the events so that we |
8757 | * won't get any samples after PERF_RECORD_EXIT. We can however still | |
8758 | * get a few PERF_RECORD_READ events. | |
9f498cc5 | 8759 | */ |
cdd6c482 | 8760 | perf_event_task(child, child_ctx, 0); |
a63eaf34 | 8761 | |
66fff224 PZ |
8762 | /* |
8763 | * We can recurse on the same lock type through: | |
8764 | * | |
cdd6c482 IM |
8765 | * __perf_event_exit_task() |
8766 | * sync_child_event() | |
a6fa941d AV |
8767 | * put_event() |
8768 | * mutex_lock(&ctx->mutex) | |
66fff224 PZ |
8769 | * |
8770 | * But since its the parent context it won't be the same instance. | |
8771 | */ | |
a0507c84 | 8772 | mutex_lock(&child_ctx->mutex); |
a63eaf34 | 8773 | |
ebf905fc | 8774 | list_for_each_entry_safe(child_event, next, &child_ctx->event_list, event_entry) |
cdd6c482 | 8775 | __perf_event_exit_task(child_event, child_ctx, child); |
8bc20959 | 8776 | |
a63eaf34 PM |
8777 | mutex_unlock(&child_ctx->mutex); |
8778 | ||
8779 | put_ctx(child_ctx); | |
9b51f66d IM |
8780 | } |
8781 | ||
8dc85d54 PZ |
8782 | /* |
8783 | * When a child task exits, feed back event values to parent events. | |
8784 | */ | |
8785 | void perf_event_exit_task(struct task_struct *child) | |
8786 | { | |
8882135b | 8787 | struct perf_event *event, *tmp; |
8dc85d54 PZ |
8788 | int ctxn; |
8789 | ||
8882135b PZ |
8790 | mutex_lock(&child->perf_event_mutex); |
8791 | list_for_each_entry_safe(event, tmp, &child->perf_event_list, | |
8792 | owner_entry) { | |
8793 | list_del_init(&event->owner_entry); | |
8794 | ||
8795 | /* | |
8796 | * Ensure the list deletion is visible before we clear | |
8797 | * the owner, closes a race against perf_release() where | |
8798 | * we need to serialize on the owner->perf_event_mutex. | |
8799 | */ | |
8800 | smp_wmb(); | |
8801 | event->owner = NULL; | |
8802 | } | |
8803 | mutex_unlock(&child->perf_event_mutex); | |
8804 | ||
8dc85d54 PZ |
8805 | for_each_task_context_nr(ctxn) |
8806 | perf_event_exit_task_context(child, ctxn); | |
4e93ad60 JO |
8807 | |
8808 | /* | |
8809 | * The perf_event_exit_task_context calls perf_event_task | |
8810 | * with child's task_ctx, which generates EXIT events for | |
8811 | * child contexts and sets child->perf_event_ctxp[] to NULL. | |
8812 | * At this point we need to send EXIT events to cpu contexts. | |
8813 | */ | |
8814 | perf_event_task(child, NULL, 0); | |
8dc85d54 PZ |
8815 | } |
8816 | ||
889ff015 FW |
8817 | static void perf_free_event(struct perf_event *event, |
8818 | struct perf_event_context *ctx) | |
8819 | { | |
8820 | struct perf_event *parent = event->parent; | |
8821 | ||
8822 | if (WARN_ON_ONCE(!parent)) | |
8823 | return; | |
8824 | ||
8825 | mutex_lock(&parent->child_mutex); | |
8826 | list_del_init(&event->child_list); | |
8827 | mutex_unlock(&parent->child_mutex); | |
8828 | ||
a6fa941d | 8829 | put_event(parent); |
889ff015 | 8830 | |
652884fe | 8831 | raw_spin_lock_irq(&ctx->lock); |
8a49542c | 8832 | perf_group_detach(event); |
889ff015 | 8833 | list_del_event(event, ctx); |
652884fe | 8834 | raw_spin_unlock_irq(&ctx->lock); |
889ff015 FW |
8835 | free_event(event); |
8836 | } | |
8837 | ||
bbbee908 | 8838 | /* |
652884fe | 8839 | * Free an unexposed, unused context as created by inheritance by |
8dc85d54 | 8840 | * perf_event_init_task below, used by fork() in case of fail. |
652884fe PZ |
8841 | * |
8842 | * Not all locks are strictly required, but take them anyway to be nice and | |
8843 | * help out with the lockdep assertions. | |
bbbee908 | 8844 | */ |
cdd6c482 | 8845 | void perf_event_free_task(struct task_struct *task) |
bbbee908 | 8846 | { |
8dc85d54 | 8847 | struct perf_event_context *ctx; |
cdd6c482 | 8848 | struct perf_event *event, *tmp; |
8dc85d54 | 8849 | int ctxn; |
bbbee908 | 8850 | |
8dc85d54 PZ |
8851 | for_each_task_context_nr(ctxn) { |
8852 | ctx = task->perf_event_ctxp[ctxn]; | |
8853 | if (!ctx) | |
8854 | continue; | |
bbbee908 | 8855 | |
8dc85d54 | 8856 | mutex_lock(&ctx->mutex); |
bbbee908 | 8857 | again: |
8dc85d54 PZ |
8858 | list_for_each_entry_safe(event, tmp, &ctx->pinned_groups, |
8859 | group_entry) | |
8860 | perf_free_event(event, ctx); | |
bbbee908 | 8861 | |
8dc85d54 PZ |
8862 | list_for_each_entry_safe(event, tmp, &ctx->flexible_groups, |
8863 | group_entry) | |
8864 | perf_free_event(event, ctx); | |
bbbee908 | 8865 | |
8dc85d54 PZ |
8866 | if (!list_empty(&ctx->pinned_groups) || |
8867 | !list_empty(&ctx->flexible_groups)) | |
8868 | goto again; | |
bbbee908 | 8869 | |
8dc85d54 | 8870 | mutex_unlock(&ctx->mutex); |
bbbee908 | 8871 | |
8dc85d54 PZ |
8872 | put_ctx(ctx); |
8873 | } | |
889ff015 FW |
8874 | } |
8875 | ||
4e231c79 PZ |
8876 | void perf_event_delayed_put(struct task_struct *task) |
8877 | { | |
8878 | int ctxn; | |
8879 | ||
8880 | for_each_task_context_nr(ctxn) | |
8881 | WARN_ON_ONCE(task->perf_event_ctxp[ctxn]); | |
8882 | } | |
8883 | ||
ffe8690c KX |
8884 | struct perf_event *perf_event_get(unsigned int fd) |
8885 | { | |
8886 | int err; | |
8887 | struct fd f; | |
8888 | struct perf_event *event; | |
8889 | ||
8890 | err = perf_fget_light(fd, &f); | |
8891 | if (err) | |
8892 | return ERR_PTR(err); | |
8893 | ||
8894 | event = f.file->private_data; | |
8895 | atomic_long_inc(&event->refcount); | |
8896 | fdput(f); | |
8897 | ||
8898 | return event; | |
8899 | } | |
8900 | ||
8901 | const struct perf_event_attr *perf_event_attrs(struct perf_event *event) | |
8902 | { | |
8903 | if (!event) | |
8904 | return ERR_PTR(-EINVAL); | |
8905 | ||
8906 | return &event->attr; | |
8907 | } | |
8908 | ||
97dee4f3 PZ |
8909 | /* |
8910 | * inherit a event from parent task to child task: | |
8911 | */ | |
8912 | static struct perf_event * | |
8913 | inherit_event(struct perf_event *parent_event, | |
8914 | struct task_struct *parent, | |
8915 | struct perf_event_context *parent_ctx, | |
8916 | struct task_struct *child, | |
8917 | struct perf_event *group_leader, | |
8918 | struct perf_event_context *child_ctx) | |
8919 | { | |
1929def9 | 8920 | enum perf_event_active_state parent_state = parent_event->state; |
97dee4f3 | 8921 | struct perf_event *child_event; |
cee010ec | 8922 | unsigned long flags; |
97dee4f3 PZ |
8923 | |
8924 | /* | |
8925 | * Instead of creating recursive hierarchies of events, | |
8926 | * we link inherited events back to the original parent, | |
8927 | * which has a filp for sure, which we use as the reference | |
8928 | * count: | |
8929 | */ | |
8930 | if (parent_event->parent) | |
8931 | parent_event = parent_event->parent; | |
8932 | ||
8933 | child_event = perf_event_alloc(&parent_event->attr, | |
8934 | parent_event->cpu, | |
d580ff86 | 8935 | child, |
97dee4f3 | 8936 | group_leader, parent_event, |
79dff51e | 8937 | NULL, NULL, -1); |
97dee4f3 PZ |
8938 | if (IS_ERR(child_event)) |
8939 | return child_event; | |
a6fa941d | 8940 | |
fadfe7be JO |
8941 | if (is_orphaned_event(parent_event) || |
8942 | !atomic_long_inc_not_zero(&parent_event->refcount)) { | |
a6fa941d AV |
8943 | free_event(child_event); |
8944 | return NULL; | |
8945 | } | |
8946 | ||
97dee4f3 PZ |
8947 | get_ctx(child_ctx); |
8948 | ||
8949 | /* | |
8950 | * Make the child state follow the state of the parent event, | |
8951 | * not its attr.disabled bit. We hold the parent's mutex, | |
8952 | * so we won't race with perf_event_{en, dis}able_family. | |
8953 | */ | |
1929def9 | 8954 | if (parent_state >= PERF_EVENT_STATE_INACTIVE) |
97dee4f3 PZ |
8955 | child_event->state = PERF_EVENT_STATE_INACTIVE; |
8956 | else | |
8957 | child_event->state = PERF_EVENT_STATE_OFF; | |
8958 | ||
8959 | if (parent_event->attr.freq) { | |
8960 | u64 sample_period = parent_event->hw.sample_period; | |
8961 | struct hw_perf_event *hwc = &child_event->hw; | |
8962 | ||
8963 | hwc->sample_period = sample_period; | |
8964 | hwc->last_period = sample_period; | |
8965 | ||
8966 | local64_set(&hwc->period_left, sample_period); | |
8967 | } | |
8968 | ||
8969 | child_event->ctx = child_ctx; | |
8970 | child_event->overflow_handler = parent_event->overflow_handler; | |
4dc0da86 AK |
8971 | child_event->overflow_handler_context |
8972 | = parent_event->overflow_handler_context; | |
97dee4f3 | 8973 | |
614b6780 TG |
8974 | /* |
8975 | * Precalculate sample_data sizes | |
8976 | */ | |
8977 | perf_event__header_size(child_event); | |
6844c09d | 8978 | perf_event__id_header_size(child_event); |
614b6780 | 8979 | |
97dee4f3 PZ |
8980 | /* |
8981 | * Link it up in the child's context: | |
8982 | */ | |
cee010ec | 8983 | raw_spin_lock_irqsave(&child_ctx->lock, flags); |
97dee4f3 | 8984 | add_event_to_ctx(child_event, child_ctx); |
cee010ec | 8985 | raw_spin_unlock_irqrestore(&child_ctx->lock, flags); |
97dee4f3 | 8986 | |
97dee4f3 PZ |
8987 | /* |
8988 | * Link this into the parent event's child list | |
8989 | */ | |
8990 | WARN_ON_ONCE(parent_event->ctx->parent_ctx); | |
8991 | mutex_lock(&parent_event->child_mutex); | |
8992 | list_add_tail(&child_event->child_list, &parent_event->child_list); | |
8993 | mutex_unlock(&parent_event->child_mutex); | |
8994 | ||
8995 | return child_event; | |
8996 | } | |
8997 | ||
8998 | static int inherit_group(struct perf_event *parent_event, | |
8999 | struct task_struct *parent, | |
9000 | struct perf_event_context *parent_ctx, | |
9001 | struct task_struct *child, | |
9002 | struct perf_event_context *child_ctx) | |
9003 | { | |
9004 | struct perf_event *leader; | |
9005 | struct perf_event *sub; | |
9006 | struct perf_event *child_ctr; | |
9007 | ||
9008 | leader = inherit_event(parent_event, parent, parent_ctx, | |
9009 | child, NULL, child_ctx); | |
9010 | if (IS_ERR(leader)) | |
9011 | return PTR_ERR(leader); | |
9012 | list_for_each_entry(sub, &parent_event->sibling_list, group_entry) { | |
9013 | child_ctr = inherit_event(sub, parent, parent_ctx, | |
9014 | child, leader, child_ctx); | |
9015 | if (IS_ERR(child_ctr)) | |
9016 | return PTR_ERR(child_ctr); | |
9017 | } | |
9018 | return 0; | |
889ff015 FW |
9019 | } |
9020 | ||
9021 | static int | |
9022 | inherit_task_group(struct perf_event *event, struct task_struct *parent, | |
9023 | struct perf_event_context *parent_ctx, | |
8dc85d54 | 9024 | struct task_struct *child, int ctxn, |
889ff015 FW |
9025 | int *inherited_all) |
9026 | { | |
9027 | int ret; | |
8dc85d54 | 9028 | struct perf_event_context *child_ctx; |
889ff015 FW |
9029 | |
9030 | if (!event->attr.inherit) { | |
9031 | *inherited_all = 0; | |
9032 | return 0; | |
bbbee908 PZ |
9033 | } |
9034 | ||
fe4b04fa | 9035 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 FW |
9036 | if (!child_ctx) { |
9037 | /* | |
9038 | * This is executed from the parent task context, so | |
9039 | * inherit events that have been marked for cloning. | |
9040 | * First allocate and initialize a context for the | |
9041 | * child. | |
9042 | */ | |
bbbee908 | 9043 | |
734df5ab | 9044 | child_ctx = alloc_perf_context(parent_ctx->pmu, child); |
889ff015 FW |
9045 | if (!child_ctx) |
9046 | return -ENOMEM; | |
bbbee908 | 9047 | |
8dc85d54 | 9048 | child->perf_event_ctxp[ctxn] = child_ctx; |
889ff015 FW |
9049 | } |
9050 | ||
9051 | ret = inherit_group(event, parent, parent_ctx, | |
9052 | child, child_ctx); | |
9053 | ||
9054 | if (ret) | |
9055 | *inherited_all = 0; | |
9056 | ||
9057 | return ret; | |
bbbee908 PZ |
9058 | } |
9059 | ||
9b51f66d | 9060 | /* |
cdd6c482 | 9061 | * Initialize the perf_event context in task_struct |
9b51f66d | 9062 | */ |
985c8dcb | 9063 | static int perf_event_init_context(struct task_struct *child, int ctxn) |
9b51f66d | 9064 | { |
889ff015 | 9065 | struct perf_event_context *child_ctx, *parent_ctx; |
cdd6c482 IM |
9066 | struct perf_event_context *cloned_ctx; |
9067 | struct perf_event *event; | |
9b51f66d | 9068 | struct task_struct *parent = current; |
564c2b21 | 9069 | int inherited_all = 1; |
dddd3379 | 9070 | unsigned long flags; |
6ab423e0 | 9071 | int ret = 0; |
9b51f66d | 9072 | |
8dc85d54 | 9073 | if (likely(!parent->perf_event_ctxp[ctxn])) |
6ab423e0 PZ |
9074 | return 0; |
9075 | ||
ad3a37de | 9076 | /* |
25346b93 PM |
9077 | * If the parent's context is a clone, pin it so it won't get |
9078 | * swapped under us. | |
ad3a37de | 9079 | */ |
8dc85d54 | 9080 | parent_ctx = perf_pin_task_context(parent, ctxn); |
ffb4ef21 PZ |
9081 | if (!parent_ctx) |
9082 | return 0; | |
25346b93 | 9083 | |
ad3a37de PM |
9084 | /* |
9085 | * No need to check if parent_ctx != NULL here; since we saw | |
9086 | * it non-NULL earlier, the only reason for it to become NULL | |
9087 | * is if we exit, and since we're currently in the middle of | |
9088 | * a fork we can't be exiting at the same time. | |
9089 | */ | |
ad3a37de | 9090 | |
9b51f66d IM |
9091 | /* |
9092 | * Lock the parent list. No need to lock the child - not PID | |
9093 | * hashed yet and not running, so nobody can access it. | |
9094 | */ | |
d859e29f | 9095 | mutex_lock(&parent_ctx->mutex); |
9b51f66d IM |
9096 | |
9097 | /* | |
9098 | * We dont have to disable NMIs - we are only looking at | |
9099 | * the list, not manipulating it: | |
9100 | */ | |
889ff015 | 9101 | list_for_each_entry(event, &parent_ctx->pinned_groups, group_entry) { |
8dc85d54 PZ |
9102 | ret = inherit_task_group(event, parent, parent_ctx, |
9103 | child, ctxn, &inherited_all); | |
889ff015 FW |
9104 | if (ret) |
9105 | break; | |
9106 | } | |
b93f7978 | 9107 | |
dddd3379 TG |
9108 | /* |
9109 | * We can't hold ctx->lock when iterating the ->flexible_group list due | |
9110 | * to allocations, but we need to prevent rotation because | |
9111 | * rotate_ctx() will change the list from interrupt context. | |
9112 | */ | |
9113 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); | |
9114 | parent_ctx->rotate_disable = 1; | |
9115 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); | |
9116 | ||
889ff015 | 9117 | list_for_each_entry(event, &parent_ctx->flexible_groups, group_entry) { |
8dc85d54 PZ |
9118 | ret = inherit_task_group(event, parent, parent_ctx, |
9119 | child, ctxn, &inherited_all); | |
889ff015 | 9120 | if (ret) |
9b51f66d | 9121 | break; |
564c2b21 PM |
9122 | } |
9123 | ||
dddd3379 TG |
9124 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); |
9125 | parent_ctx->rotate_disable = 0; | |
dddd3379 | 9126 | |
8dc85d54 | 9127 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 | 9128 | |
05cbaa28 | 9129 | if (child_ctx && inherited_all) { |
564c2b21 PM |
9130 | /* |
9131 | * Mark the child context as a clone of the parent | |
9132 | * context, or of whatever the parent is a clone of. | |
c5ed5145 PZ |
9133 | * |
9134 | * Note that if the parent is a clone, the holding of | |
9135 | * parent_ctx->lock avoids it from being uncloned. | |
564c2b21 | 9136 | */ |
c5ed5145 | 9137 | cloned_ctx = parent_ctx->parent_ctx; |
ad3a37de PM |
9138 | if (cloned_ctx) { |
9139 | child_ctx->parent_ctx = cloned_ctx; | |
25346b93 | 9140 | child_ctx->parent_gen = parent_ctx->parent_gen; |
564c2b21 PM |
9141 | } else { |
9142 | child_ctx->parent_ctx = parent_ctx; | |
9143 | child_ctx->parent_gen = parent_ctx->generation; | |
9144 | } | |
9145 | get_ctx(child_ctx->parent_ctx); | |
9b51f66d IM |
9146 | } |
9147 | ||
c5ed5145 | 9148 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); |
d859e29f | 9149 | mutex_unlock(&parent_ctx->mutex); |
6ab423e0 | 9150 | |
25346b93 | 9151 | perf_unpin_context(parent_ctx); |
fe4b04fa | 9152 | put_ctx(parent_ctx); |
ad3a37de | 9153 | |
6ab423e0 | 9154 | return ret; |
9b51f66d IM |
9155 | } |
9156 | ||
8dc85d54 PZ |
9157 | /* |
9158 | * Initialize the perf_event context in task_struct | |
9159 | */ | |
9160 | int perf_event_init_task(struct task_struct *child) | |
9161 | { | |
9162 | int ctxn, ret; | |
9163 | ||
8550d7cb ON |
9164 | memset(child->perf_event_ctxp, 0, sizeof(child->perf_event_ctxp)); |
9165 | mutex_init(&child->perf_event_mutex); | |
9166 | INIT_LIST_HEAD(&child->perf_event_list); | |
9167 | ||
8dc85d54 PZ |
9168 | for_each_task_context_nr(ctxn) { |
9169 | ret = perf_event_init_context(child, ctxn); | |
6c72e350 PZ |
9170 | if (ret) { |
9171 | perf_event_free_task(child); | |
8dc85d54 | 9172 | return ret; |
6c72e350 | 9173 | } |
8dc85d54 PZ |
9174 | } |
9175 | ||
9176 | return 0; | |
9177 | } | |
9178 | ||
220b140b PM |
9179 | static void __init perf_event_init_all_cpus(void) |
9180 | { | |
b28ab83c | 9181 | struct swevent_htable *swhash; |
220b140b | 9182 | int cpu; |
220b140b PM |
9183 | |
9184 | for_each_possible_cpu(cpu) { | |
b28ab83c PZ |
9185 | swhash = &per_cpu(swevent_htable, cpu); |
9186 | mutex_init(&swhash->hlist_mutex); | |
2fde4f94 | 9187 | INIT_LIST_HEAD(&per_cpu(active_ctx_list, cpu)); |
220b140b PM |
9188 | } |
9189 | } | |
9190 | ||
0db0628d | 9191 | static void perf_event_init_cpu(int cpu) |
0793a61d | 9192 | { |
108b02cf | 9193 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
0793a61d | 9194 | |
b28ab83c | 9195 | mutex_lock(&swhash->hlist_mutex); |
4536e4d1 | 9196 | if (swhash->hlist_refcount > 0) { |
76e1d904 FW |
9197 | struct swevent_hlist *hlist; |
9198 | ||
b28ab83c PZ |
9199 | hlist = kzalloc_node(sizeof(*hlist), GFP_KERNEL, cpu_to_node(cpu)); |
9200 | WARN_ON(!hlist); | |
9201 | rcu_assign_pointer(swhash->swevent_hlist, hlist); | |
76e1d904 | 9202 | } |
b28ab83c | 9203 | mutex_unlock(&swhash->hlist_mutex); |
0793a61d TG |
9204 | } |
9205 | ||
2965faa5 | 9206 | #if defined CONFIG_HOTPLUG_CPU || defined CONFIG_KEXEC_CORE |
108b02cf | 9207 | static void __perf_event_exit_context(void *__info) |
0793a61d | 9208 | { |
226424ee | 9209 | struct remove_event re = { .detach_group = true }; |
108b02cf | 9210 | struct perf_event_context *ctx = __info; |
0793a61d | 9211 | |
e3703f8c | 9212 | rcu_read_lock(); |
46ce0fe9 PZ |
9213 | list_for_each_entry_rcu(re.event, &ctx->event_list, event_entry) |
9214 | __perf_remove_from_context(&re); | |
e3703f8c | 9215 | rcu_read_unlock(); |
0793a61d | 9216 | } |
108b02cf PZ |
9217 | |
9218 | static void perf_event_exit_cpu_context(int cpu) | |
9219 | { | |
9220 | struct perf_event_context *ctx; | |
9221 | struct pmu *pmu; | |
9222 | int idx; | |
9223 | ||
9224 | idx = srcu_read_lock(&pmus_srcu); | |
9225 | list_for_each_entry_rcu(pmu, &pmus, entry) { | |
917bdd1c | 9226 | ctx = &per_cpu_ptr(pmu->pmu_cpu_context, cpu)->ctx; |
108b02cf PZ |
9227 | |
9228 | mutex_lock(&ctx->mutex); | |
9229 | smp_call_function_single(cpu, __perf_event_exit_context, ctx, 1); | |
9230 | mutex_unlock(&ctx->mutex); | |
9231 | } | |
9232 | srcu_read_unlock(&pmus_srcu, idx); | |
108b02cf PZ |
9233 | } |
9234 | ||
cdd6c482 | 9235 | static void perf_event_exit_cpu(int cpu) |
0793a61d | 9236 | { |
e3703f8c | 9237 | perf_event_exit_cpu_context(cpu); |
0793a61d TG |
9238 | } |
9239 | #else | |
cdd6c482 | 9240 | static inline void perf_event_exit_cpu(int cpu) { } |
0793a61d TG |
9241 | #endif |
9242 | ||
c277443c PZ |
9243 | static int |
9244 | perf_reboot(struct notifier_block *notifier, unsigned long val, void *v) | |
9245 | { | |
9246 | int cpu; | |
9247 | ||
9248 | for_each_online_cpu(cpu) | |
9249 | perf_event_exit_cpu(cpu); | |
9250 | ||
9251 | return NOTIFY_OK; | |
9252 | } | |
9253 | ||
9254 | /* | |
9255 | * Run the perf reboot notifier at the very last possible moment so that | |
9256 | * the generic watchdog code runs as long as possible. | |
9257 | */ | |
9258 | static struct notifier_block perf_reboot_notifier = { | |
9259 | .notifier_call = perf_reboot, | |
9260 | .priority = INT_MIN, | |
9261 | }; | |
9262 | ||
0db0628d | 9263 | static int |
0793a61d TG |
9264 | perf_cpu_notify(struct notifier_block *self, unsigned long action, void *hcpu) |
9265 | { | |
9266 | unsigned int cpu = (long)hcpu; | |
9267 | ||
4536e4d1 | 9268 | switch (action & ~CPU_TASKS_FROZEN) { |
0793a61d TG |
9269 | |
9270 | case CPU_UP_PREPARE: | |
5e11637e | 9271 | case CPU_DOWN_FAILED: |
cdd6c482 | 9272 | perf_event_init_cpu(cpu); |
0793a61d TG |
9273 | break; |
9274 | ||
5e11637e | 9275 | case CPU_UP_CANCELED: |
0793a61d | 9276 | case CPU_DOWN_PREPARE: |
cdd6c482 | 9277 | perf_event_exit_cpu(cpu); |
0793a61d | 9278 | break; |
0793a61d TG |
9279 | default: |
9280 | break; | |
9281 | } | |
9282 | ||
9283 | return NOTIFY_OK; | |
9284 | } | |
9285 | ||
cdd6c482 | 9286 | void __init perf_event_init(void) |
0793a61d | 9287 | { |
3c502e7a JW |
9288 | int ret; |
9289 | ||
2e80a82a PZ |
9290 | idr_init(&pmu_idr); |
9291 | ||
220b140b | 9292 | perf_event_init_all_cpus(); |
b0a873eb | 9293 | init_srcu_struct(&pmus_srcu); |
2e80a82a PZ |
9294 | perf_pmu_register(&perf_swevent, "software", PERF_TYPE_SOFTWARE); |
9295 | perf_pmu_register(&perf_cpu_clock, NULL, -1); | |
9296 | perf_pmu_register(&perf_task_clock, NULL, -1); | |
b0a873eb PZ |
9297 | perf_tp_register(); |
9298 | perf_cpu_notifier(perf_cpu_notify); | |
c277443c | 9299 | register_reboot_notifier(&perf_reboot_notifier); |
3c502e7a JW |
9300 | |
9301 | ret = init_hw_breakpoint(); | |
9302 | WARN(ret, "hw_breakpoint initialization failed with: %d", ret); | |
b2029520 GN |
9303 | |
9304 | /* do not patch jump label more than once per second */ | |
9305 | jump_label_rate_limit(&perf_sched_events, HZ); | |
b01c3a00 JO |
9306 | |
9307 | /* | |
9308 | * Build time assertion that we keep the data_head at the intended | |
9309 | * location. IOW, validation we got the __reserved[] size right. | |
9310 | */ | |
9311 | BUILD_BUG_ON((offsetof(struct perf_event_mmap_page, data_head)) | |
9312 | != 1024); | |
0793a61d | 9313 | } |
abe43400 | 9314 | |
fd979c01 CS |
9315 | ssize_t perf_event_sysfs_show(struct device *dev, struct device_attribute *attr, |
9316 | char *page) | |
9317 | { | |
9318 | struct perf_pmu_events_attr *pmu_attr = | |
9319 | container_of(attr, struct perf_pmu_events_attr, attr); | |
9320 | ||
9321 | if (pmu_attr->event_str) | |
9322 | return sprintf(page, "%s\n", pmu_attr->event_str); | |
9323 | ||
9324 | return 0; | |
9325 | } | |
9326 | ||
abe43400 PZ |
9327 | static int __init perf_event_sysfs_init(void) |
9328 | { | |
9329 | struct pmu *pmu; | |
9330 | int ret; | |
9331 | ||
9332 | mutex_lock(&pmus_lock); | |
9333 | ||
9334 | ret = bus_register(&pmu_bus); | |
9335 | if (ret) | |
9336 | goto unlock; | |
9337 | ||
9338 | list_for_each_entry(pmu, &pmus, entry) { | |
9339 | if (!pmu->name || pmu->type < 0) | |
9340 | continue; | |
9341 | ||
9342 | ret = pmu_dev_alloc(pmu); | |
9343 | WARN(ret, "Failed to register pmu: %s, reason %d\n", pmu->name, ret); | |
9344 | } | |
9345 | pmu_bus_running = 1; | |
9346 | ret = 0; | |
9347 | ||
9348 | unlock: | |
9349 | mutex_unlock(&pmus_lock); | |
9350 | ||
9351 | return ret; | |
9352 | } | |
9353 | device_initcall(perf_event_sysfs_init); | |
e5d1367f SE |
9354 | |
9355 | #ifdef CONFIG_CGROUP_PERF | |
eb95419b TH |
9356 | static struct cgroup_subsys_state * |
9357 | perf_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) | |
e5d1367f SE |
9358 | { |
9359 | struct perf_cgroup *jc; | |
e5d1367f | 9360 | |
1b15d055 | 9361 | jc = kzalloc(sizeof(*jc), GFP_KERNEL); |
e5d1367f SE |
9362 | if (!jc) |
9363 | return ERR_PTR(-ENOMEM); | |
9364 | ||
e5d1367f SE |
9365 | jc->info = alloc_percpu(struct perf_cgroup_info); |
9366 | if (!jc->info) { | |
9367 | kfree(jc); | |
9368 | return ERR_PTR(-ENOMEM); | |
9369 | } | |
9370 | ||
e5d1367f SE |
9371 | return &jc->css; |
9372 | } | |
9373 | ||
eb95419b | 9374 | static void perf_cgroup_css_free(struct cgroup_subsys_state *css) |
e5d1367f | 9375 | { |
eb95419b TH |
9376 | struct perf_cgroup *jc = container_of(css, struct perf_cgroup, css); |
9377 | ||
e5d1367f SE |
9378 | free_percpu(jc->info); |
9379 | kfree(jc); | |
9380 | } | |
9381 | ||
9382 | static int __perf_cgroup_move(void *info) | |
9383 | { | |
9384 | struct task_struct *task = info; | |
ddaaf4e2 | 9385 | rcu_read_lock(); |
e5d1367f | 9386 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT | PERF_CGROUP_SWIN); |
ddaaf4e2 | 9387 | rcu_read_unlock(); |
e5d1367f SE |
9388 | return 0; |
9389 | } | |
9390 | ||
1f7dd3e5 | 9391 | static void perf_cgroup_attach(struct cgroup_taskset *tset) |
e5d1367f | 9392 | { |
bb9d97b6 | 9393 | struct task_struct *task; |
1f7dd3e5 | 9394 | struct cgroup_subsys_state *css; |
bb9d97b6 | 9395 | |
1f7dd3e5 | 9396 | cgroup_taskset_for_each(task, css, tset) |
bb9d97b6 | 9397 | task_function_call(task, __perf_cgroup_move, task); |
e5d1367f SE |
9398 | } |
9399 | ||
073219e9 | 9400 | struct cgroup_subsys perf_event_cgrp_subsys = { |
92fb9748 TH |
9401 | .css_alloc = perf_cgroup_css_alloc, |
9402 | .css_free = perf_cgroup_css_free, | |
bb9d97b6 | 9403 | .attach = perf_cgroup_attach, |
e5d1367f SE |
9404 | }; |
9405 | #endif /* CONFIG_CGROUP_PERF */ |