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 | ||
272325c4 PZ |
52 | typedef int (*remote_function_f)(void *); |
53 | ||
fe4b04fa | 54 | struct remote_function_call { |
e7e7ee2e | 55 | struct task_struct *p; |
272325c4 | 56 | remote_function_f func; |
e7e7ee2e IM |
57 | void *info; |
58 | int ret; | |
fe4b04fa PZ |
59 | }; |
60 | ||
61 | static void remote_function(void *data) | |
62 | { | |
63 | struct remote_function_call *tfc = data; | |
64 | struct task_struct *p = tfc->p; | |
65 | ||
66 | if (p) { | |
0da4cf3e PZ |
67 | /* -EAGAIN */ |
68 | if (task_cpu(p) != smp_processor_id()) | |
69 | return; | |
70 | ||
71 | /* | |
72 | * Now that we're on right CPU with IRQs disabled, we can test | |
73 | * if we hit the right task without races. | |
74 | */ | |
75 | ||
76 | tfc->ret = -ESRCH; /* No such (running) process */ | |
77 | if (p != current) | |
fe4b04fa PZ |
78 | return; |
79 | } | |
80 | ||
81 | tfc->ret = tfc->func(tfc->info); | |
82 | } | |
83 | ||
84 | /** | |
85 | * task_function_call - call a function on the cpu on which a task runs | |
86 | * @p: the task to evaluate | |
87 | * @func: the function to be called | |
88 | * @info: the function call argument | |
89 | * | |
90 | * Calls the function @func when the task is currently running. This might | |
91 | * be on the current CPU, which just calls the function directly | |
92 | * | |
93 | * returns: @func return value, or | |
94 | * -ESRCH - when the process isn't running | |
95 | * -EAGAIN - when the process moved away | |
96 | */ | |
97 | static int | |
272325c4 | 98 | task_function_call(struct task_struct *p, remote_function_f func, void *info) |
fe4b04fa PZ |
99 | { |
100 | struct remote_function_call data = { | |
e7e7ee2e IM |
101 | .p = p, |
102 | .func = func, | |
103 | .info = info, | |
0da4cf3e | 104 | .ret = -EAGAIN, |
fe4b04fa | 105 | }; |
0da4cf3e | 106 | int ret; |
fe4b04fa | 107 | |
0da4cf3e PZ |
108 | do { |
109 | ret = smp_call_function_single(task_cpu(p), remote_function, &data, 1); | |
110 | if (!ret) | |
111 | ret = data.ret; | |
112 | } while (ret == -EAGAIN); | |
fe4b04fa | 113 | |
0da4cf3e | 114 | return ret; |
fe4b04fa PZ |
115 | } |
116 | ||
117 | /** | |
118 | * cpu_function_call - call a function on the cpu | |
119 | * @func: the function to be called | |
120 | * @info: the function call argument | |
121 | * | |
122 | * Calls the function @func on the remote cpu. | |
123 | * | |
124 | * returns: @func return value or -ENXIO when the cpu is offline | |
125 | */ | |
272325c4 | 126 | static int cpu_function_call(int cpu, remote_function_f func, void *info) |
fe4b04fa PZ |
127 | { |
128 | struct remote_function_call data = { | |
e7e7ee2e IM |
129 | .p = NULL, |
130 | .func = func, | |
131 | .info = info, | |
132 | .ret = -ENXIO, /* No such CPU */ | |
fe4b04fa PZ |
133 | }; |
134 | ||
135 | smp_call_function_single(cpu, remote_function, &data, 1); | |
136 | ||
137 | return data.ret; | |
138 | } | |
139 | ||
fae3fde6 PZ |
140 | static inline struct perf_cpu_context * |
141 | __get_cpu_context(struct perf_event_context *ctx) | |
142 | { | |
143 | return this_cpu_ptr(ctx->pmu->pmu_cpu_context); | |
144 | } | |
145 | ||
146 | static void perf_ctx_lock(struct perf_cpu_context *cpuctx, | |
147 | struct perf_event_context *ctx) | |
0017960f | 148 | { |
fae3fde6 PZ |
149 | raw_spin_lock(&cpuctx->ctx.lock); |
150 | if (ctx) | |
151 | raw_spin_lock(&ctx->lock); | |
152 | } | |
153 | ||
154 | static void perf_ctx_unlock(struct perf_cpu_context *cpuctx, | |
155 | struct perf_event_context *ctx) | |
156 | { | |
157 | if (ctx) | |
158 | raw_spin_unlock(&ctx->lock); | |
159 | raw_spin_unlock(&cpuctx->ctx.lock); | |
160 | } | |
161 | ||
63b6da39 PZ |
162 | #define TASK_TOMBSTONE ((void *)-1L) |
163 | ||
164 | static bool is_kernel_event(struct perf_event *event) | |
165 | { | |
f47c02c0 | 166 | return READ_ONCE(event->owner) == TASK_TOMBSTONE; |
63b6da39 PZ |
167 | } |
168 | ||
39a43640 PZ |
169 | /* |
170 | * On task ctx scheduling... | |
171 | * | |
172 | * When !ctx->nr_events a task context will not be scheduled. This means | |
173 | * we can disable the scheduler hooks (for performance) without leaving | |
174 | * pending task ctx state. | |
175 | * | |
176 | * This however results in two special cases: | |
177 | * | |
178 | * - removing the last event from a task ctx; this is relatively straight | |
179 | * forward and is done in __perf_remove_from_context. | |
180 | * | |
181 | * - adding the first event to a task ctx; this is tricky because we cannot | |
182 | * rely on ctx->is_active and therefore cannot use event_function_call(). | |
183 | * See perf_install_in_context(). | |
184 | * | |
39a43640 PZ |
185 | * If ctx->nr_events, then ctx->is_active and cpuctx->task_ctx are set. |
186 | */ | |
187 | ||
fae3fde6 PZ |
188 | typedef void (*event_f)(struct perf_event *, struct perf_cpu_context *, |
189 | struct perf_event_context *, void *); | |
190 | ||
191 | struct event_function_struct { | |
192 | struct perf_event *event; | |
193 | event_f func; | |
194 | void *data; | |
195 | }; | |
196 | ||
197 | static int event_function(void *info) | |
198 | { | |
199 | struct event_function_struct *efs = info; | |
200 | struct perf_event *event = efs->event; | |
0017960f | 201 | struct perf_event_context *ctx = event->ctx; |
fae3fde6 PZ |
202 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
203 | struct perf_event_context *task_ctx = cpuctx->task_ctx; | |
63b6da39 | 204 | int ret = 0; |
fae3fde6 PZ |
205 | |
206 | WARN_ON_ONCE(!irqs_disabled()); | |
207 | ||
63b6da39 | 208 | perf_ctx_lock(cpuctx, task_ctx); |
fae3fde6 PZ |
209 | /* |
210 | * Since we do the IPI call without holding ctx->lock things can have | |
211 | * changed, double check we hit the task we set out to hit. | |
fae3fde6 PZ |
212 | */ |
213 | if (ctx->task) { | |
63b6da39 | 214 | if (ctx->task != current) { |
0da4cf3e | 215 | ret = -ESRCH; |
63b6da39 PZ |
216 | goto unlock; |
217 | } | |
fae3fde6 | 218 | |
fae3fde6 PZ |
219 | /* |
220 | * We only use event_function_call() on established contexts, | |
221 | * and event_function() is only ever called when active (or | |
222 | * rather, we'll have bailed in task_function_call() or the | |
223 | * above ctx->task != current test), therefore we must have | |
224 | * ctx->is_active here. | |
225 | */ | |
226 | WARN_ON_ONCE(!ctx->is_active); | |
227 | /* | |
228 | * And since we have ctx->is_active, cpuctx->task_ctx must | |
229 | * match. | |
230 | */ | |
63b6da39 PZ |
231 | WARN_ON_ONCE(task_ctx != ctx); |
232 | } else { | |
233 | WARN_ON_ONCE(&cpuctx->ctx != ctx); | |
fae3fde6 | 234 | } |
63b6da39 | 235 | |
fae3fde6 | 236 | efs->func(event, cpuctx, ctx, efs->data); |
63b6da39 | 237 | unlock: |
fae3fde6 PZ |
238 | perf_ctx_unlock(cpuctx, task_ctx); |
239 | ||
63b6da39 | 240 | return ret; |
fae3fde6 PZ |
241 | } |
242 | ||
243 | static void event_function_local(struct perf_event *event, event_f func, void *data) | |
244 | { | |
245 | struct event_function_struct efs = { | |
246 | .event = event, | |
247 | .func = func, | |
248 | .data = data, | |
249 | }; | |
250 | ||
251 | int ret = event_function(&efs); | |
252 | WARN_ON_ONCE(ret); | |
253 | } | |
254 | ||
255 | static void event_function_call(struct perf_event *event, event_f func, void *data) | |
0017960f PZ |
256 | { |
257 | struct perf_event_context *ctx = event->ctx; | |
63b6da39 | 258 | struct task_struct *task = READ_ONCE(ctx->task); /* verified in event_function */ |
fae3fde6 PZ |
259 | struct event_function_struct efs = { |
260 | .event = event, | |
261 | .func = func, | |
262 | .data = data, | |
263 | }; | |
0017960f | 264 | |
c97f4736 PZ |
265 | if (!event->parent) { |
266 | /* | |
267 | * If this is a !child event, we must hold ctx::mutex to | |
268 | * stabilize the the event->ctx relation. See | |
269 | * perf_event_ctx_lock(). | |
270 | */ | |
271 | lockdep_assert_held(&ctx->mutex); | |
272 | } | |
0017960f PZ |
273 | |
274 | if (!task) { | |
fae3fde6 | 275 | cpu_function_call(event->cpu, event_function, &efs); |
0017960f PZ |
276 | return; |
277 | } | |
278 | ||
63b6da39 PZ |
279 | if (task == TASK_TOMBSTONE) |
280 | return; | |
281 | ||
a096309b | 282 | again: |
fae3fde6 | 283 | if (!task_function_call(task, event_function, &efs)) |
0017960f PZ |
284 | return; |
285 | ||
286 | raw_spin_lock_irq(&ctx->lock); | |
63b6da39 PZ |
287 | /* |
288 | * Reload the task pointer, it might have been changed by | |
289 | * a concurrent perf_event_context_sched_out(). | |
290 | */ | |
291 | task = ctx->task; | |
a096309b PZ |
292 | if (task == TASK_TOMBSTONE) { |
293 | raw_spin_unlock_irq(&ctx->lock); | |
294 | return; | |
0017960f | 295 | } |
a096309b PZ |
296 | if (ctx->is_active) { |
297 | raw_spin_unlock_irq(&ctx->lock); | |
298 | goto again; | |
299 | } | |
300 | func(event, NULL, ctx, data); | |
0017960f PZ |
301 | raw_spin_unlock_irq(&ctx->lock); |
302 | } | |
303 | ||
e5d1367f SE |
304 | #define PERF_FLAG_ALL (PERF_FLAG_FD_NO_GROUP |\ |
305 | PERF_FLAG_FD_OUTPUT |\ | |
a21b0b35 YD |
306 | PERF_FLAG_PID_CGROUP |\ |
307 | PERF_FLAG_FD_CLOEXEC) | |
e5d1367f | 308 | |
bce38cd5 SE |
309 | /* |
310 | * branch priv levels that need permission checks | |
311 | */ | |
312 | #define PERF_SAMPLE_BRANCH_PERM_PLM \ | |
313 | (PERF_SAMPLE_BRANCH_KERNEL |\ | |
314 | PERF_SAMPLE_BRANCH_HV) | |
315 | ||
0b3fcf17 SE |
316 | enum event_type_t { |
317 | EVENT_FLEXIBLE = 0x1, | |
318 | EVENT_PINNED = 0x2, | |
3cbaa590 | 319 | EVENT_TIME = 0x4, |
0b3fcf17 SE |
320 | EVENT_ALL = EVENT_FLEXIBLE | EVENT_PINNED, |
321 | }; | |
322 | ||
e5d1367f SE |
323 | /* |
324 | * perf_sched_events : >0 events exist | |
325 | * perf_cgroup_events: >0 per-cpu cgroup events exist on this cpu | |
326 | */ | |
9107c89e PZ |
327 | |
328 | static void perf_sched_delayed(struct work_struct *work); | |
329 | DEFINE_STATIC_KEY_FALSE(perf_sched_events); | |
330 | static DECLARE_DELAYED_WORK(perf_sched_work, perf_sched_delayed); | |
331 | static DEFINE_MUTEX(perf_sched_mutex); | |
332 | static atomic_t perf_sched_count; | |
333 | ||
e5d1367f | 334 | static DEFINE_PER_CPU(atomic_t, perf_cgroup_events); |
ba532500 | 335 | static DEFINE_PER_CPU(int, perf_sched_cb_usages); |
e5d1367f | 336 | |
cdd6c482 IM |
337 | static atomic_t nr_mmap_events __read_mostly; |
338 | static atomic_t nr_comm_events __read_mostly; | |
339 | static atomic_t nr_task_events __read_mostly; | |
948b26b6 | 340 | static atomic_t nr_freq_events __read_mostly; |
45ac1403 | 341 | static atomic_t nr_switch_events __read_mostly; |
9ee318a7 | 342 | |
108b02cf PZ |
343 | static LIST_HEAD(pmus); |
344 | static DEFINE_MUTEX(pmus_lock); | |
345 | static struct srcu_struct pmus_srcu; | |
346 | ||
0764771d | 347 | /* |
cdd6c482 | 348 | * perf event paranoia level: |
0fbdea19 IM |
349 | * -1 - not paranoid at all |
350 | * 0 - disallow raw tracepoint access for unpriv | |
cdd6c482 | 351 | * 1 - disallow cpu events for unpriv |
0fbdea19 | 352 | * 2 - disallow kernel profiling for unpriv |
0764771d | 353 | */ |
cdd6c482 | 354 | int sysctl_perf_event_paranoid __read_mostly = 1; |
0764771d | 355 | |
20443384 FW |
356 | /* Minimum for 512 kiB + 1 user control page */ |
357 | int sysctl_perf_event_mlock __read_mostly = 512 + (PAGE_SIZE / 1024); /* 'free' kiB per user */ | |
df58ab24 PZ |
358 | |
359 | /* | |
cdd6c482 | 360 | * max perf event sample rate |
df58ab24 | 361 | */ |
14c63f17 DH |
362 | #define DEFAULT_MAX_SAMPLE_RATE 100000 |
363 | #define DEFAULT_SAMPLE_PERIOD_NS (NSEC_PER_SEC / DEFAULT_MAX_SAMPLE_RATE) | |
364 | #define DEFAULT_CPU_TIME_MAX_PERCENT 25 | |
365 | ||
366 | int sysctl_perf_event_sample_rate __read_mostly = DEFAULT_MAX_SAMPLE_RATE; | |
367 | ||
368 | static int max_samples_per_tick __read_mostly = DIV_ROUND_UP(DEFAULT_MAX_SAMPLE_RATE, HZ); | |
369 | static int perf_sample_period_ns __read_mostly = DEFAULT_SAMPLE_PERIOD_NS; | |
370 | ||
d9494cb4 PZ |
371 | static int perf_sample_allowed_ns __read_mostly = |
372 | DEFAULT_SAMPLE_PERIOD_NS * DEFAULT_CPU_TIME_MAX_PERCENT / 100; | |
14c63f17 | 373 | |
18ab2cd3 | 374 | static void update_perf_cpu_limits(void) |
14c63f17 DH |
375 | { |
376 | u64 tmp = perf_sample_period_ns; | |
377 | ||
378 | tmp *= sysctl_perf_cpu_time_max_percent; | |
e5302920 | 379 | do_div(tmp, 100); |
d9494cb4 | 380 | ACCESS_ONCE(perf_sample_allowed_ns) = tmp; |
14c63f17 | 381 | } |
163ec435 | 382 | |
9e630205 SE |
383 | static int perf_rotate_context(struct perf_cpu_context *cpuctx); |
384 | ||
163ec435 PZ |
385 | int perf_proc_update_handler(struct ctl_table *table, int write, |
386 | void __user *buffer, size_t *lenp, | |
387 | loff_t *ppos) | |
388 | { | |
723478c8 | 389 | int ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
163ec435 PZ |
390 | |
391 | if (ret || !write) | |
392 | return ret; | |
393 | ||
394 | max_samples_per_tick = DIV_ROUND_UP(sysctl_perf_event_sample_rate, HZ); | |
14c63f17 DH |
395 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; |
396 | update_perf_cpu_limits(); | |
397 | ||
398 | return 0; | |
399 | } | |
400 | ||
401 | int sysctl_perf_cpu_time_max_percent __read_mostly = DEFAULT_CPU_TIME_MAX_PERCENT; | |
402 | ||
403 | int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write, | |
404 | void __user *buffer, size_t *lenp, | |
405 | loff_t *ppos) | |
406 | { | |
407 | int ret = proc_dointvec(table, write, buffer, lenp, ppos); | |
408 | ||
409 | if (ret || !write) | |
410 | return ret; | |
411 | ||
412 | update_perf_cpu_limits(); | |
163ec435 PZ |
413 | |
414 | return 0; | |
415 | } | |
1ccd1549 | 416 | |
14c63f17 DH |
417 | /* |
418 | * perf samples are done in some very critical code paths (NMIs). | |
419 | * If they take too much CPU time, the system can lock up and not | |
420 | * get any real work done. This will drop the sample rate when | |
421 | * we detect that events are taking too long. | |
422 | */ | |
423 | #define NR_ACCUMULATED_SAMPLES 128 | |
d9494cb4 | 424 | static DEFINE_PER_CPU(u64, running_sample_length); |
14c63f17 | 425 | |
6a02ad66 | 426 | static void perf_duration_warn(struct irq_work *w) |
14c63f17 | 427 | { |
6a02ad66 | 428 | u64 allowed_ns = ACCESS_ONCE(perf_sample_allowed_ns); |
14c63f17 | 429 | u64 avg_local_sample_len; |
e5302920 | 430 | u64 local_samples_len; |
6a02ad66 | 431 | |
4a32fea9 | 432 | local_samples_len = __this_cpu_read(running_sample_length); |
6a02ad66 PZ |
433 | avg_local_sample_len = local_samples_len/NR_ACCUMULATED_SAMPLES; |
434 | ||
435 | printk_ratelimited(KERN_WARNING | |
436 | "perf interrupt took too long (%lld > %lld), lowering " | |
437 | "kernel.perf_event_max_sample_rate to %d\n", | |
cd578abb | 438 | avg_local_sample_len, allowed_ns >> 1, |
6a02ad66 PZ |
439 | sysctl_perf_event_sample_rate); |
440 | } | |
441 | ||
442 | static DEFINE_IRQ_WORK(perf_duration_work, perf_duration_warn); | |
443 | ||
444 | void perf_sample_event_took(u64 sample_len_ns) | |
445 | { | |
d9494cb4 | 446 | u64 allowed_ns = ACCESS_ONCE(perf_sample_allowed_ns); |
6a02ad66 PZ |
447 | u64 avg_local_sample_len; |
448 | u64 local_samples_len; | |
14c63f17 | 449 | |
d9494cb4 | 450 | if (allowed_ns == 0) |
14c63f17 DH |
451 | return; |
452 | ||
453 | /* decay the counter by 1 average sample */ | |
4a32fea9 | 454 | local_samples_len = __this_cpu_read(running_sample_length); |
14c63f17 DH |
455 | local_samples_len -= local_samples_len/NR_ACCUMULATED_SAMPLES; |
456 | local_samples_len += sample_len_ns; | |
4a32fea9 | 457 | __this_cpu_write(running_sample_length, local_samples_len); |
14c63f17 DH |
458 | |
459 | /* | |
460 | * note: this will be biased artifically low until we have | |
461 | * seen NR_ACCUMULATED_SAMPLES. Doing it this way keeps us | |
462 | * from having to maintain a count. | |
463 | */ | |
464 | avg_local_sample_len = local_samples_len/NR_ACCUMULATED_SAMPLES; | |
465 | ||
d9494cb4 | 466 | if (avg_local_sample_len <= allowed_ns) |
14c63f17 DH |
467 | return; |
468 | ||
469 | if (max_samples_per_tick <= 1) | |
470 | return; | |
471 | ||
472 | max_samples_per_tick = DIV_ROUND_UP(max_samples_per_tick, 2); | |
473 | sysctl_perf_event_sample_rate = max_samples_per_tick * HZ; | |
474 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; | |
475 | ||
14c63f17 | 476 | update_perf_cpu_limits(); |
6a02ad66 | 477 | |
cd578abb PZ |
478 | if (!irq_work_queue(&perf_duration_work)) { |
479 | early_printk("perf interrupt took too long (%lld > %lld), lowering " | |
480 | "kernel.perf_event_max_sample_rate to %d\n", | |
481 | avg_local_sample_len, allowed_ns >> 1, | |
482 | sysctl_perf_event_sample_rate); | |
483 | } | |
14c63f17 DH |
484 | } |
485 | ||
cdd6c482 | 486 | static atomic64_t perf_event_id; |
a96bbc16 | 487 | |
0b3fcf17 SE |
488 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, |
489 | enum event_type_t event_type); | |
490 | ||
491 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
492 | enum event_type_t event_type, |
493 | struct task_struct *task); | |
494 | ||
495 | static void update_context_time(struct perf_event_context *ctx); | |
496 | static u64 perf_event_time(struct perf_event *event); | |
0b3fcf17 | 497 | |
cdd6c482 | 498 | void __weak perf_event_print_debug(void) { } |
0793a61d | 499 | |
84c79910 | 500 | extern __weak const char *perf_pmu_name(void) |
0793a61d | 501 | { |
84c79910 | 502 | return "pmu"; |
0793a61d TG |
503 | } |
504 | ||
0b3fcf17 SE |
505 | static inline u64 perf_clock(void) |
506 | { | |
507 | return local_clock(); | |
508 | } | |
509 | ||
34f43927 PZ |
510 | static inline u64 perf_event_clock(struct perf_event *event) |
511 | { | |
512 | return event->clock(); | |
513 | } | |
514 | ||
e5d1367f SE |
515 | #ifdef CONFIG_CGROUP_PERF |
516 | ||
e5d1367f SE |
517 | static inline bool |
518 | perf_cgroup_match(struct perf_event *event) | |
519 | { | |
520 | struct perf_event_context *ctx = event->ctx; | |
521 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
522 | ||
ef824fa1 TH |
523 | /* @event doesn't care about cgroup */ |
524 | if (!event->cgrp) | |
525 | return true; | |
526 | ||
527 | /* wants specific cgroup scope but @cpuctx isn't associated with any */ | |
528 | if (!cpuctx->cgrp) | |
529 | return false; | |
530 | ||
531 | /* | |
532 | * Cgroup scoping is recursive. An event enabled for a cgroup is | |
533 | * also enabled for all its descendant cgroups. If @cpuctx's | |
534 | * cgroup is a descendant of @event's (the test covers identity | |
535 | * case), it's a match. | |
536 | */ | |
537 | return cgroup_is_descendant(cpuctx->cgrp->css.cgroup, | |
538 | event->cgrp->css.cgroup); | |
e5d1367f SE |
539 | } |
540 | ||
e5d1367f SE |
541 | static inline void perf_detach_cgroup(struct perf_event *event) |
542 | { | |
4e2ba650 | 543 | css_put(&event->cgrp->css); |
e5d1367f SE |
544 | event->cgrp = NULL; |
545 | } | |
546 | ||
547 | static inline int is_cgroup_event(struct perf_event *event) | |
548 | { | |
549 | return event->cgrp != NULL; | |
550 | } | |
551 | ||
552 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
553 | { | |
554 | struct perf_cgroup_info *t; | |
555 | ||
556 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
557 | return t->time; | |
558 | } | |
559 | ||
560 | static inline void __update_cgrp_time(struct perf_cgroup *cgrp) | |
561 | { | |
562 | struct perf_cgroup_info *info; | |
563 | u64 now; | |
564 | ||
565 | now = perf_clock(); | |
566 | ||
567 | info = this_cpu_ptr(cgrp->info); | |
568 | ||
569 | info->time += now - info->timestamp; | |
570 | info->timestamp = now; | |
571 | } | |
572 | ||
573 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
574 | { | |
575 | struct perf_cgroup *cgrp_out = cpuctx->cgrp; | |
576 | if (cgrp_out) | |
577 | __update_cgrp_time(cgrp_out); | |
578 | } | |
579 | ||
580 | static inline void update_cgrp_time_from_event(struct perf_event *event) | |
581 | { | |
3f7cce3c SE |
582 | struct perf_cgroup *cgrp; |
583 | ||
e5d1367f | 584 | /* |
3f7cce3c SE |
585 | * ensure we access cgroup data only when needed and |
586 | * when we know the cgroup is pinned (css_get) | |
e5d1367f | 587 | */ |
3f7cce3c | 588 | if (!is_cgroup_event(event)) |
e5d1367f SE |
589 | return; |
590 | ||
614e4c4e | 591 | cgrp = perf_cgroup_from_task(current, event->ctx); |
3f7cce3c SE |
592 | /* |
593 | * Do not update time when cgroup is not active | |
594 | */ | |
595 | if (cgrp == event->cgrp) | |
596 | __update_cgrp_time(event->cgrp); | |
e5d1367f SE |
597 | } |
598 | ||
599 | static inline void | |
3f7cce3c SE |
600 | perf_cgroup_set_timestamp(struct task_struct *task, |
601 | struct perf_event_context *ctx) | |
e5d1367f SE |
602 | { |
603 | struct perf_cgroup *cgrp; | |
604 | struct perf_cgroup_info *info; | |
605 | ||
3f7cce3c SE |
606 | /* |
607 | * ctx->lock held by caller | |
608 | * ensure we do not access cgroup data | |
609 | * unless we have the cgroup pinned (css_get) | |
610 | */ | |
611 | if (!task || !ctx->nr_cgroups) | |
e5d1367f SE |
612 | return; |
613 | ||
614e4c4e | 614 | cgrp = perf_cgroup_from_task(task, ctx); |
e5d1367f | 615 | info = this_cpu_ptr(cgrp->info); |
3f7cce3c | 616 | info->timestamp = ctx->timestamp; |
e5d1367f SE |
617 | } |
618 | ||
619 | #define PERF_CGROUP_SWOUT 0x1 /* cgroup switch out every event */ | |
620 | #define PERF_CGROUP_SWIN 0x2 /* cgroup switch in events based on task */ | |
621 | ||
622 | /* | |
623 | * reschedule events based on the cgroup constraint of task. | |
624 | * | |
625 | * mode SWOUT : schedule out everything | |
626 | * mode SWIN : schedule in based on cgroup for next | |
627 | */ | |
18ab2cd3 | 628 | static void perf_cgroup_switch(struct task_struct *task, int mode) |
e5d1367f SE |
629 | { |
630 | struct perf_cpu_context *cpuctx; | |
631 | struct pmu *pmu; | |
632 | unsigned long flags; | |
633 | ||
634 | /* | |
635 | * disable interrupts to avoid geting nr_cgroup | |
636 | * changes via __perf_event_disable(). Also | |
637 | * avoids preemption. | |
638 | */ | |
639 | local_irq_save(flags); | |
640 | ||
641 | /* | |
642 | * we reschedule only in the presence of cgroup | |
643 | * constrained events. | |
644 | */ | |
e5d1367f SE |
645 | |
646 | list_for_each_entry_rcu(pmu, &pmus, entry) { | |
e5d1367f | 647 | cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
95cf59ea PZ |
648 | if (cpuctx->unique_pmu != pmu) |
649 | continue; /* ensure we process each cpuctx once */ | |
e5d1367f | 650 | |
e5d1367f SE |
651 | /* |
652 | * perf_cgroup_events says at least one | |
653 | * context on this CPU has cgroup events. | |
654 | * | |
655 | * ctx->nr_cgroups reports the number of cgroup | |
656 | * events for a context. | |
657 | */ | |
658 | if (cpuctx->ctx.nr_cgroups > 0) { | |
facc4307 PZ |
659 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
660 | perf_pmu_disable(cpuctx->ctx.pmu); | |
e5d1367f SE |
661 | |
662 | if (mode & PERF_CGROUP_SWOUT) { | |
663 | cpu_ctx_sched_out(cpuctx, EVENT_ALL); | |
664 | /* | |
665 | * must not be done before ctxswout due | |
666 | * to event_filter_match() in event_sched_out() | |
667 | */ | |
668 | cpuctx->cgrp = NULL; | |
669 | } | |
670 | ||
671 | if (mode & PERF_CGROUP_SWIN) { | |
e566b76e | 672 | WARN_ON_ONCE(cpuctx->cgrp); |
95cf59ea PZ |
673 | /* |
674 | * set cgrp before ctxsw in to allow | |
675 | * event_filter_match() to not have to pass | |
676 | * task around | |
614e4c4e SE |
677 | * we pass the cpuctx->ctx to perf_cgroup_from_task() |
678 | * because cgorup events are only per-cpu | |
e5d1367f | 679 | */ |
614e4c4e | 680 | cpuctx->cgrp = perf_cgroup_from_task(task, &cpuctx->ctx); |
e5d1367f SE |
681 | cpu_ctx_sched_in(cpuctx, EVENT_ALL, task); |
682 | } | |
facc4307 PZ |
683 | perf_pmu_enable(cpuctx->ctx.pmu); |
684 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
e5d1367f | 685 | } |
e5d1367f SE |
686 | } |
687 | ||
e5d1367f SE |
688 | local_irq_restore(flags); |
689 | } | |
690 | ||
a8d757ef SE |
691 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
692 | struct task_struct *next) | |
e5d1367f | 693 | { |
a8d757ef SE |
694 | struct perf_cgroup *cgrp1; |
695 | struct perf_cgroup *cgrp2 = NULL; | |
696 | ||
ddaaf4e2 | 697 | rcu_read_lock(); |
a8d757ef SE |
698 | /* |
699 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
700 | * we do not need to pass the ctx here because we know |
701 | * we are holding the rcu lock | |
a8d757ef | 702 | */ |
614e4c4e | 703 | cgrp1 = perf_cgroup_from_task(task, NULL); |
70a01657 | 704 | cgrp2 = perf_cgroup_from_task(next, NULL); |
a8d757ef SE |
705 | |
706 | /* | |
707 | * only schedule out current cgroup events if we know | |
708 | * that we are switching to a different cgroup. Otherwise, | |
709 | * do no touch the cgroup events. | |
710 | */ | |
711 | if (cgrp1 != cgrp2) | |
712 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT); | |
ddaaf4e2 SE |
713 | |
714 | rcu_read_unlock(); | |
e5d1367f SE |
715 | } |
716 | ||
a8d757ef SE |
717 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
718 | struct task_struct *task) | |
e5d1367f | 719 | { |
a8d757ef SE |
720 | struct perf_cgroup *cgrp1; |
721 | struct perf_cgroup *cgrp2 = NULL; | |
722 | ||
ddaaf4e2 | 723 | rcu_read_lock(); |
a8d757ef SE |
724 | /* |
725 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
726 | * we do not need to pass the ctx here because we know |
727 | * we are holding the rcu lock | |
a8d757ef | 728 | */ |
614e4c4e | 729 | cgrp1 = perf_cgroup_from_task(task, NULL); |
614e4c4e | 730 | cgrp2 = perf_cgroup_from_task(prev, NULL); |
a8d757ef SE |
731 | |
732 | /* | |
733 | * only need to schedule in cgroup events if we are changing | |
734 | * cgroup during ctxsw. Cgroup events were not scheduled | |
735 | * out of ctxsw out if that was not the case. | |
736 | */ | |
737 | if (cgrp1 != cgrp2) | |
738 | perf_cgroup_switch(task, PERF_CGROUP_SWIN); | |
ddaaf4e2 SE |
739 | |
740 | rcu_read_unlock(); | |
e5d1367f SE |
741 | } |
742 | ||
743 | static inline int perf_cgroup_connect(int fd, struct perf_event *event, | |
744 | struct perf_event_attr *attr, | |
745 | struct perf_event *group_leader) | |
746 | { | |
747 | struct perf_cgroup *cgrp; | |
748 | struct cgroup_subsys_state *css; | |
2903ff01 AV |
749 | struct fd f = fdget(fd); |
750 | int ret = 0; | |
e5d1367f | 751 | |
2903ff01 | 752 | if (!f.file) |
e5d1367f SE |
753 | return -EBADF; |
754 | ||
b583043e | 755 | css = css_tryget_online_from_dir(f.file->f_path.dentry, |
ec903c0c | 756 | &perf_event_cgrp_subsys); |
3db272c0 LZ |
757 | if (IS_ERR(css)) { |
758 | ret = PTR_ERR(css); | |
759 | goto out; | |
760 | } | |
e5d1367f SE |
761 | |
762 | cgrp = container_of(css, struct perf_cgroup, css); | |
763 | event->cgrp = cgrp; | |
764 | ||
765 | /* | |
766 | * all events in a group must monitor | |
767 | * the same cgroup because a task belongs | |
768 | * to only one perf cgroup at a time | |
769 | */ | |
770 | if (group_leader && group_leader->cgrp != cgrp) { | |
771 | perf_detach_cgroup(event); | |
772 | ret = -EINVAL; | |
e5d1367f | 773 | } |
3db272c0 | 774 | out: |
2903ff01 | 775 | fdput(f); |
e5d1367f SE |
776 | return ret; |
777 | } | |
778 | ||
779 | static inline void | |
780 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
781 | { | |
782 | struct perf_cgroup_info *t; | |
783 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
784 | event->shadow_ctx_time = now - t->timestamp; | |
785 | } | |
786 | ||
787 | static inline void | |
788 | perf_cgroup_defer_enabled(struct perf_event *event) | |
789 | { | |
790 | /* | |
791 | * when the current task's perf cgroup does not match | |
792 | * the event's, we need to remember to call the | |
793 | * perf_mark_enable() function the first time a task with | |
794 | * a matching perf cgroup is scheduled in. | |
795 | */ | |
796 | if (is_cgroup_event(event) && !perf_cgroup_match(event)) | |
797 | event->cgrp_defer_enabled = 1; | |
798 | } | |
799 | ||
800 | static inline void | |
801 | perf_cgroup_mark_enabled(struct perf_event *event, | |
802 | struct perf_event_context *ctx) | |
803 | { | |
804 | struct perf_event *sub; | |
805 | u64 tstamp = perf_event_time(event); | |
806 | ||
807 | if (!event->cgrp_defer_enabled) | |
808 | return; | |
809 | ||
810 | event->cgrp_defer_enabled = 0; | |
811 | ||
812 | event->tstamp_enabled = tstamp - event->total_time_enabled; | |
813 | list_for_each_entry(sub, &event->sibling_list, group_entry) { | |
814 | if (sub->state >= PERF_EVENT_STATE_INACTIVE) { | |
815 | sub->tstamp_enabled = tstamp - sub->total_time_enabled; | |
816 | sub->cgrp_defer_enabled = 0; | |
817 | } | |
818 | } | |
819 | } | |
820 | #else /* !CONFIG_CGROUP_PERF */ | |
821 | ||
822 | static inline bool | |
823 | perf_cgroup_match(struct perf_event *event) | |
824 | { | |
825 | return true; | |
826 | } | |
827 | ||
828 | static inline void perf_detach_cgroup(struct perf_event *event) | |
829 | {} | |
830 | ||
831 | static inline int is_cgroup_event(struct perf_event *event) | |
832 | { | |
833 | return 0; | |
834 | } | |
835 | ||
836 | static inline u64 perf_cgroup_event_cgrp_time(struct perf_event *event) | |
837 | { | |
838 | return 0; | |
839 | } | |
840 | ||
841 | static inline void update_cgrp_time_from_event(struct perf_event *event) | |
842 | { | |
843 | } | |
844 | ||
845 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
846 | { | |
847 | } | |
848 | ||
a8d757ef SE |
849 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
850 | struct task_struct *next) | |
e5d1367f SE |
851 | { |
852 | } | |
853 | ||
a8d757ef SE |
854 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
855 | struct task_struct *task) | |
e5d1367f SE |
856 | { |
857 | } | |
858 | ||
859 | static inline int perf_cgroup_connect(pid_t pid, struct perf_event *event, | |
860 | struct perf_event_attr *attr, | |
861 | struct perf_event *group_leader) | |
862 | { | |
863 | return -EINVAL; | |
864 | } | |
865 | ||
866 | static inline void | |
3f7cce3c SE |
867 | perf_cgroup_set_timestamp(struct task_struct *task, |
868 | struct perf_event_context *ctx) | |
e5d1367f SE |
869 | { |
870 | } | |
871 | ||
872 | void | |
873 | perf_cgroup_switch(struct task_struct *task, struct task_struct *next) | |
874 | { | |
875 | } | |
876 | ||
877 | static inline void | |
878 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
879 | { | |
880 | } | |
881 | ||
882 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
883 | { | |
884 | return 0; | |
885 | } | |
886 | ||
887 | static inline void | |
888 | perf_cgroup_defer_enabled(struct perf_event *event) | |
889 | { | |
890 | } | |
891 | ||
892 | static inline void | |
893 | perf_cgroup_mark_enabled(struct perf_event *event, | |
894 | struct perf_event_context *ctx) | |
895 | { | |
896 | } | |
897 | #endif | |
898 | ||
9e630205 SE |
899 | /* |
900 | * set default to be dependent on timer tick just | |
901 | * like original code | |
902 | */ | |
903 | #define PERF_CPU_HRTIMER (1000 / HZ) | |
904 | /* | |
905 | * function must be called with interrupts disbled | |
906 | */ | |
272325c4 | 907 | static enum hrtimer_restart perf_mux_hrtimer_handler(struct hrtimer *hr) |
9e630205 SE |
908 | { |
909 | struct perf_cpu_context *cpuctx; | |
9e630205 SE |
910 | int rotations = 0; |
911 | ||
912 | WARN_ON(!irqs_disabled()); | |
913 | ||
914 | cpuctx = container_of(hr, struct perf_cpu_context, hrtimer); | |
9e630205 SE |
915 | rotations = perf_rotate_context(cpuctx); |
916 | ||
4cfafd30 PZ |
917 | raw_spin_lock(&cpuctx->hrtimer_lock); |
918 | if (rotations) | |
9e630205 | 919 | hrtimer_forward_now(hr, cpuctx->hrtimer_interval); |
4cfafd30 PZ |
920 | else |
921 | cpuctx->hrtimer_active = 0; | |
922 | raw_spin_unlock(&cpuctx->hrtimer_lock); | |
9e630205 | 923 | |
4cfafd30 | 924 | return rotations ? HRTIMER_RESTART : HRTIMER_NORESTART; |
9e630205 SE |
925 | } |
926 | ||
272325c4 | 927 | static void __perf_mux_hrtimer_init(struct perf_cpu_context *cpuctx, int cpu) |
9e630205 | 928 | { |
272325c4 | 929 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 930 | struct pmu *pmu = cpuctx->ctx.pmu; |
272325c4 | 931 | u64 interval; |
9e630205 SE |
932 | |
933 | /* no multiplexing needed for SW PMU */ | |
934 | if (pmu->task_ctx_nr == perf_sw_context) | |
935 | return; | |
936 | ||
62b85639 SE |
937 | /* |
938 | * check default is sane, if not set then force to | |
939 | * default interval (1/tick) | |
940 | */ | |
272325c4 PZ |
941 | interval = pmu->hrtimer_interval_ms; |
942 | if (interval < 1) | |
943 | interval = pmu->hrtimer_interval_ms = PERF_CPU_HRTIMER; | |
62b85639 | 944 | |
272325c4 | 945 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * interval); |
9e630205 | 946 | |
4cfafd30 PZ |
947 | raw_spin_lock_init(&cpuctx->hrtimer_lock); |
948 | hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_PINNED); | |
272325c4 | 949 | timer->function = perf_mux_hrtimer_handler; |
9e630205 SE |
950 | } |
951 | ||
272325c4 | 952 | static int perf_mux_hrtimer_restart(struct perf_cpu_context *cpuctx) |
9e630205 | 953 | { |
272325c4 | 954 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 955 | struct pmu *pmu = cpuctx->ctx.pmu; |
4cfafd30 | 956 | unsigned long flags; |
9e630205 SE |
957 | |
958 | /* not for SW PMU */ | |
959 | if (pmu->task_ctx_nr == perf_sw_context) | |
272325c4 | 960 | return 0; |
9e630205 | 961 | |
4cfafd30 PZ |
962 | raw_spin_lock_irqsave(&cpuctx->hrtimer_lock, flags); |
963 | if (!cpuctx->hrtimer_active) { | |
964 | cpuctx->hrtimer_active = 1; | |
965 | hrtimer_forward_now(timer, cpuctx->hrtimer_interval); | |
966 | hrtimer_start_expires(timer, HRTIMER_MODE_ABS_PINNED); | |
967 | } | |
968 | raw_spin_unlock_irqrestore(&cpuctx->hrtimer_lock, flags); | |
9e630205 | 969 | |
272325c4 | 970 | return 0; |
9e630205 SE |
971 | } |
972 | ||
33696fc0 | 973 | void perf_pmu_disable(struct pmu *pmu) |
9e35ad38 | 974 | { |
33696fc0 PZ |
975 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
976 | if (!(*count)++) | |
977 | pmu->pmu_disable(pmu); | |
9e35ad38 | 978 | } |
9e35ad38 | 979 | |
33696fc0 | 980 | void perf_pmu_enable(struct pmu *pmu) |
9e35ad38 | 981 | { |
33696fc0 PZ |
982 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
983 | if (!--(*count)) | |
984 | pmu->pmu_enable(pmu); | |
9e35ad38 | 985 | } |
9e35ad38 | 986 | |
2fde4f94 | 987 | static DEFINE_PER_CPU(struct list_head, active_ctx_list); |
e9d2b064 PZ |
988 | |
989 | /* | |
2fde4f94 MR |
990 | * perf_event_ctx_activate(), perf_event_ctx_deactivate(), and |
991 | * perf_event_task_tick() are fully serialized because they're strictly cpu | |
992 | * affine and perf_event_ctx{activate,deactivate} are called with IRQs | |
993 | * disabled, while perf_event_task_tick is called from IRQ context. | |
e9d2b064 | 994 | */ |
2fde4f94 | 995 | static void perf_event_ctx_activate(struct perf_event_context *ctx) |
9e35ad38 | 996 | { |
2fde4f94 | 997 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
b5ab4cd5 | 998 | |
e9d2b064 | 999 | WARN_ON(!irqs_disabled()); |
b5ab4cd5 | 1000 | |
2fde4f94 MR |
1001 | WARN_ON(!list_empty(&ctx->active_ctx_list)); |
1002 | ||
1003 | list_add(&ctx->active_ctx_list, head); | |
1004 | } | |
1005 | ||
1006 | static void perf_event_ctx_deactivate(struct perf_event_context *ctx) | |
1007 | { | |
1008 | WARN_ON(!irqs_disabled()); | |
1009 | ||
1010 | WARN_ON(list_empty(&ctx->active_ctx_list)); | |
1011 | ||
1012 | list_del_init(&ctx->active_ctx_list); | |
9e35ad38 | 1013 | } |
9e35ad38 | 1014 | |
cdd6c482 | 1015 | static void get_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1016 | { |
e5289d4a | 1017 | WARN_ON(!atomic_inc_not_zero(&ctx->refcount)); |
a63eaf34 PM |
1018 | } |
1019 | ||
4af57ef2 YZ |
1020 | static void free_ctx(struct rcu_head *head) |
1021 | { | |
1022 | struct perf_event_context *ctx; | |
1023 | ||
1024 | ctx = container_of(head, struct perf_event_context, rcu_head); | |
1025 | kfree(ctx->task_ctx_data); | |
1026 | kfree(ctx); | |
1027 | } | |
1028 | ||
cdd6c482 | 1029 | static void put_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1030 | { |
564c2b21 PM |
1031 | if (atomic_dec_and_test(&ctx->refcount)) { |
1032 | if (ctx->parent_ctx) | |
1033 | put_ctx(ctx->parent_ctx); | |
63b6da39 | 1034 | if (ctx->task && ctx->task != TASK_TOMBSTONE) |
c93f7669 | 1035 | put_task_struct(ctx->task); |
4af57ef2 | 1036 | call_rcu(&ctx->rcu_head, free_ctx); |
564c2b21 | 1037 | } |
a63eaf34 PM |
1038 | } |
1039 | ||
f63a8daa PZ |
1040 | /* |
1041 | * Because of perf_event::ctx migration in sys_perf_event_open::move_group and | |
1042 | * perf_pmu_migrate_context() we need some magic. | |
1043 | * | |
1044 | * Those places that change perf_event::ctx will hold both | |
1045 | * perf_event_ctx::mutex of the 'old' and 'new' ctx value. | |
1046 | * | |
8b10c5e2 PZ |
1047 | * Lock ordering is by mutex address. There are two other sites where |
1048 | * perf_event_context::mutex nests and those are: | |
1049 | * | |
1050 | * - perf_event_exit_task_context() [ child , 0 ] | |
8ba289b8 PZ |
1051 | * perf_event_exit_event() |
1052 | * put_event() [ parent, 1 ] | |
8b10c5e2 PZ |
1053 | * |
1054 | * - perf_event_init_context() [ parent, 0 ] | |
1055 | * inherit_task_group() | |
1056 | * inherit_group() | |
1057 | * inherit_event() | |
1058 | * perf_event_alloc() | |
1059 | * perf_init_event() | |
1060 | * perf_try_init_event() [ child , 1 ] | |
1061 | * | |
1062 | * While it appears there is an obvious deadlock here -- the parent and child | |
1063 | * nesting levels are inverted between the two. This is in fact safe because | |
1064 | * life-time rules separate them. That is an exiting task cannot fork, and a | |
1065 | * spawning task cannot (yet) exit. | |
1066 | * | |
1067 | * But remember that that these are parent<->child context relations, and | |
1068 | * migration does not affect children, therefore these two orderings should not | |
1069 | * interact. | |
f63a8daa PZ |
1070 | * |
1071 | * The change in perf_event::ctx does not affect children (as claimed above) | |
1072 | * because the sys_perf_event_open() case will install a new event and break | |
1073 | * the ctx parent<->child relation, and perf_pmu_migrate_context() is only | |
1074 | * concerned with cpuctx and that doesn't have children. | |
1075 | * | |
1076 | * The places that change perf_event::ctx will issue: | |
1077 | * | |
1078 | * perf_remove_from_context(); | |
1079 | * synchronize_rcu(); | |
1080 | * perf_install_in_context(); | |
1081 | * | |
1082 | * to affect the change. The remove_from_context() + synchronize_rcu() should | |
1083 | * quiesce the event, after which we can install it in the new location. This | |
1084 | * means that only external vectors (perf_fops, prctl) can perturb the event | |
1085 | * while in transit. Therefore all such accessors should also acquire | |
1086 | * perf_event_context::mutex to serialize against this. | |
1087 | * | |
1088 | * However; because event->ctx can change while we're waiting to acquire | |
1089 | * ctx->mutex we must be careful and use the below perf_event_ctx_lock() | |
1090 | * function. | |
1091 | * | |
1092 | * Lock order: | |
1093 | * task_struct::perf_event_mutex | |
1094 | * perf_event_context::mutex | |
f63a8daa | 1095 | * perf_event::child_mutex; |
07c4a776 | 1096 | * perf_event_context::lock |
f63a8daa PZ |
1097 | * perf_event::mmap_mutex |
1098 | * mmap_sem | |
1099 | */ | |
a83fe28e PZ |
1100 | static struct perf_event_context * |
1101 | perf_event_ctx_lock_nested(struct perf_event *event, int nesting) | |
f63a8daa PZ |
1102 | { |
1103 | struct perf_event_context *ctx; | |
1104 | ||
1105 | again: | |
1106 | rcu_read_lock(); | |
1107 | ctx = ACCESS_ONCE(event->ctx); | |
1108 | if (!atomic_inc_not_zero(&ctx->refcount)) { | |
1109 | rcu_read_unlock(); | |
1110 | goto again; | |
1111 | } | |
1112 | rcu_read_unlock(); | |
1113 | ||
a83fe28e | 1114 | mutex_lock_nested(&ctx->mutex, nesting); |
f63a8daa PZ |
1115 | if (event->ctx != ctx) { |
1116 | mutex_unlock(&ctx->mutex); | |
1117 | put_ctx(ctx); | |
1118 | goto again; | |
1119 | } | |
1120 | ||
1121 | return ctx; | |
1122 | } | |
1123 | ||
a83fe28e PZ |
1124 | static inline struct perf_event_context * |
1125 | perf_event_ctx_lock(struct perf_event *event) | |
1126 | { | |
1127 | return perf_event_ctx_lock_nested(event, 0); | |
1128 | } | |
1129 | ||
f63a8daa PZ |
1130 | static void perf_event_ctx_unlock(struct perf_event *event, |
1131 | struct perf_event_context *ctx) | |
1132 | { | |
1133 | mutex_unlock(&ctx->mutex); | |
1134 | put_ctx(ctx); | |
1135 | } | |
1136 | ||
211de6eb PZ |
1137 | /* |
1138 | * This must be done under the ctx->lock, such as to serialize against | |
1139 | * context_equiv(), therefore we cannot call put_ctx() since that might end up | |
1140 | * calling scheduler related locks and ctx->lock nests inside those. | |
1141 | */ | |
1142 | static __must_check struct perf_event_context * | |
1143 | unclone_ctx(struct perf_event_context *ctx) | |
71a851b4 | 1144 | { |
211de6eb PZ |
1145 | struct perf_event_context *parent_ctx = ctx->parent_ctx; |
1146 | ||
1147 | lockdep_assert_held(&ctx->lock); | |
1148 | ||
1149 | if (parent_ctx) | |
71a851b4 | 1150 | ctx->parent_ctx = NULL; |
5a3126d4 | 1151 | ctx->generation++; |
211de6eb PZ |
1152 | |
1153 | return parent_ctx; | |
71a851b4 PZ |
1154 | } |
1155 | ||
6844c09d ACM |
1156 | static u32 perf_event_pid(struct perf_event *event, struct task_struct *p) |
1157 | { | |
1158 | /* | |
1159 | * only top level events have the pid namespace they were created in | |
1160 | */ | |
1161 | if (event->parent) | |
1162 | event = event->parent; | |
1163 | ||
1164 | return task_tgid_nr_ns(p, event->ns); | |
1165 | } | |
1166 | ||
1167 | static u32 perf_event_tid(struct perf_event *event, struct task_struct *p) | |
1168 | { | |
1169 | /* | |
1170 | * only top level events have the pid namespace they were created in | |
1171 | */ | |
1172 | if (event->parent) | |
1173 | event = event->parent; | |
1174 | ||
1175 | return task_pid_nr_ns(p, event->ns); | |
1176 | } | |
1177 | ||
7f453c24 | 1178 | /* |
cdd6c482 | 1179 | * If we inherit events we want to return the parent event id |
7f453c24 PZ |
1180 | * to userspace. |
1181 | */ | |
cdd6c482 | 1182 | static u64 primary_event_id(struct perf_event *event) |
7f453c24 | 1183 | { |
cdd6c482 | 1184 | u64 id = event->id; |
7f453c24 | 1185 | |
cdd6c482 IM |
1186 | if (event->parent) |
1187 | id = event->parent->id; | |
7f453c24 PZ |
1188 | |
1189 | return id; | |
1190 | } | |
1191 | ||
25346b93 | 1192 | /* |
cdd6c482 | 1193 | * Get the perf_event_context for a task and lock it. |
63b6da39 | 1194 | * |
25346b93 PM |
1195 | * This has to cope with with the fact that until it is locked, |
1196 | * the context could get moved to another task. | |
1197 | */ | |
cdd6c482 | 1198 | static struct perf_event_context * |
8dc85d54 | 1199 | perf_lock_task_context(struct task_struct *task, int ctxn, unsigned long *flags) |
25346b93 | 1200 | { |
cdd6c482 | 1201 | struct perf_event_context *ctx; |
25346b93 | 1202 | |
9ed6060d | 1203 | retry: |
058ebd0e PZ |
1204 | /* |
1205 | * One of the few rules of preemptible RCU is that one cannot do | |
1206 | * rcu_read_unlock() while holding a scheduler (or nested) lock when | |
2fd59077 | 1207 | * part of the read side critical section was irqs-enabled -- see |
058ebd0e PZ |
1208 | * rcu_read_unlock_special(). |
1209 | * | |
1210 | * Since ctx->lock nests under rq->lock we must ensure the entire read | |
2fd59077 | 1211 | * side critical section has interrupts disabled. |
058ebd0e | 1212 | */ |
2fd59077 | 1213 | local_irq_save(*flags); |
058ebd0e | 1214 | rcu_read_lock(); |
8dc85d54 | 1215 | ctx = rcu_dereference(task->perf_event_ctxp[ctxn]); |
25346b93 PM |
1216 | if (ctx) { |
1217 | /* | |
1218 | * If this context is a clone of another, it might | |
1219 | * get swapped for another underneath us by | |
cdd6c482 | 1220 | * perf_event_task_sched_out, though the |
25346b93 PM |
1221 | * rcu_read_lock() protects us from any context |
1222 | * getting freed. Lock the context and check if it | |
1223 | * got swapped before we could get the lock, and retry | |
1224 | * if so. If we locked the right context, then it | |
1225 | * can't get swapped on us any more. | |
1226 | */ | |
2fd59077 | 1227 | raw_spin_lock(&ctx->lock); |
8dc85d54 | 1228 | if (ctx != rcu_dereference(task->perf_event_ctxp[ctxn])) { |
2fd59077 | 1229 | raw_spin_unlock(&ctx->lock); |
058ebd0e | 1230 | rcu_read_unlock(); |
2fd59077 | 1231 | local_irq_restore(*flags); |
25346b93 PM |
1232 | goto retry; |
1233 | } | |
b49a9e7e | 1234 | |
63b6da39 PZ |
1235 | if (ctx->task == TASK_TOMBSTONE || |
1236 | !atomic_inc_not_zero(&ctx->refcount)) { | |
2fd59077 | 1237 | raw_spin_unlock(&ctx->lock); |
b49a9e7e | 1238 | ctx = NULL; |
828b6f0e PZ |
1239 | } else { |
1240 | WARN_ON_ONCE(ctx->task != task); | |
b49a9e7e | 1241 | } |
25346b93 PM |
1242 | } |
1243 | rcu_read_unlock(); | |
2fd59077 PM |
1244 | if (!ctx) |
1245 | local_irq_restore(*flags); | |
25346b93 PM |
1246 | return ctx; |
1247 | } | |
1248 | ||
1249 | /* | |
1250 | * Get the context for a task and increment its pin_count so it | |
1251 | * can't get swapped to another task. This also increments its | |
1252 | * reference count so that the context can't get freed. | |
1253 | */ | |
8dc85d54 PZ |
1254 | static struct perf_event_context * |
1255 | perf_pin_task_context(struct task_struct *task, int ctxn) | |
25346b93 | 1256 | { |
cdd6c482 | 1257 | struct perf_event_context *ctx; |
25346b93 PM |
1258 | unsigned long flags; |
1259 | ||
8dc85d54 | 1260 | ctx = perf_lock_task_context(task, ctxn, &flags); |
25346b93 PM |
1261 | if (ctx) { |
1262 | ++ctx->pin_count; | |
e625cce1 | 1263 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1264 | } |
1265 | return ctx; | |
1266 | } | |
1267 | ||
cdd6c482 | 1268 | static void perf_unpin_context(struct perf_event_context *ctx) |
25346b93 PM |
1269 | { |
1270 | unsigned long flags; | |
1271 | ||
e625cce1 | 1272 | raw_spin_lock_irqsave(&ctx->lock, flags); |
25346b93 | 1273 | --ctx->pin_count; |
e625cce1 | 1274 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1275 | } |
1276 | ||
f67218c3 PZ |
1277 | /* |
1278 | * Update the record of the current time in a context. | |
1279 | */ | |
1280 | static void update_context_time(struct perf_event_context *ctx) | |
1281 | { | |
1282 | u64 now = perf_clock(); | |
1283 | ||
1284 | ctx->time += now - ctx->timestamp; | |
1285 | ctx->timestamp = now; | |
1286 | } | |
1287 | ||
4158755d SE |
1288 | static u64 perf_event_time(struct perf_event *event) |
1289 | { | |
1290 | struct perf_event_context *ctx = event->ctx; | |
e5d1367f SE |
1291 | |
1292 | if (is_cgroup_event(event)) | |
1293 | return perf_cgroup_event_time(event); | |
1294 | ||
4158755d SE |
1295 | return ctx ? ctx->time : 0; |
1296 | } | |
1297 | ||
f67218c3 PZ |
1298 | /* |
1299 | * Update the total_time_enabled and total_time_running fields for a event. | |
1300 | */ | |
1301 | static void update_event_times(struct perf_event *event) | |
1302 | { | |
1303 | struct perf_event_context *ctx = event->ctx; | |
1304 | u64 run_end; | |
1305 | ||
3cbaa590 PZ |
1306 | lockdep_assert_held(&ctx->lock); |
1307 | ||
f67218c3 PZ |
1308 | if (event->state < PERF_EVENT_STATE_INACTIVE || |
1309 | event->group_leader->state < PERF_EVENT_STATE_INACTIVE) | |
1310 | return; | |
3cbaa590 | 1311 | |
e5d1367f SE |
1312 | /* |
1313 | * in cgroup mode, time_enabled represents | |
1314 | * the time the event was enabled AND active | |
1315 | * tasks were in the monitored cgroup. This is | |
1316 | * independent of the activity of the context as | |
1317 | * there may be a mix of cgroup and non-cgroup events. | |
1318 | * | |
1319 | * That is why we treat cgroup events differently | |
1320 | * here. | |
1321 | */ | |
1322 | if (is_cgroup_event(event)) | |
46cd6a7f | 1323 | run_end = perf_cgroup_event_time(event); |
e5d1367f SE |
1324 | else if (ctx->is_active) |
1325 | run_end = ctx->time; | |
acd1d7c1 PZ |
1326 | else |
1327 | run_end = event->tstamp_stopped; | |
1328 | ||
1329 | event->total_time_enabled = run_end - event->tstamp_enabled; | |
f67218c3 PZ |
1330 | |
1331 | if (event->state == PERF_EVENT_STATE_INACTIVE) | |
1332 | run_end = event->tstamp_stopped; | |
1333 | else | |
4158755d | 1334 | run_end = perf_event_time(event); |
f67218c3 PZ |
1335 | |
1336 | event->total_time_running = run_end - event->tstamp_running; | |
e5d1367f | 1337 | |
f67218c3 PZ |
1338 | } |
1339 | ||
96c21a46 PZ |
1340 | /* |
1341 | * Update total_time_enabled and total_time_running for all events in a group. | |
1342 | */ | |
1343 | static void update_group_times(struct perf_event *leader) | |
1344 | { | |
1345 | struct perf_event *event; | |
1346 | ||
1347 | update_event_times(leader); | |
1348 | list_for_each_entry(event, &leader->sibling_list, group_entry) | |
1349 | update_event_times(event); | |
1350 | } | |
1351 | ||
889ff015 FW |
1352 | static struct list_head * |
1353 | ctx_group_list(struct perf_event *event, struct perf_event_context *ctx) | |
1354 | { | |
1355 | if (event->attr.pinned) | |
1356 | return &ctx->pinned_groups; | |
1357 | else | |
1358 | return &ctx->flexible_groups; | |
1359 | } | |
1360 | ||
fccc714b | 1361 | /* |
cdd6c482 | 1362 | * Add a event from the lists for its context. |
fccc714b PZ |
1363 | * Must be called with ctx->mutex and ctx->lock held. |
1364 | */ | |
04289bb9 | 1365 | static void |
cdd6c482 | 1366 | list_add_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1367 | { |
c994d613 PZ |
1368 | lockdep_assert_held(&ctx->lock); |
1369 | ||
8a49542c PZ |
1370 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); |
1371 | event->attach_state |= PERF_ATTACH_CONTEXT; | |
04289bb9 IM |
1372 | |
1373 | /* | |
8a49542c PZ |
1374 | * If we're a stand alone event or group leader, we go to the context |
1375 | * list, group events are kept attached to the group so that | |
1376 | * perf_group_detach can, at all times, locate all siblings. | |
04289bb9 | 1377 | */ |
8a49542c | 1378 | if (event->group_leader == event) { |
889ff015 FW |
1379 | struct list_head *list; |
1380 | ||
d6f962b5 FW |
1381 | if (is_software_event(event)) |
1382 | event->group_flags |= PERF_GROUP_SOFTWARE; | |
1383 | ||
889ff015 FW |
1384 | list = ctx_group_list(event, ctx); |
1385 | list_add_tail(&event->group_entry, list); | |
5c148194 | 1386 | } |
592903cd | 1387 | |
08309379 | 1388 | if (is_cgroup_event(event)) |
e5d1367f | 1389 | ctx->nr_cgroups++; |
e5d1367f | 1390 | |
cdd6c482 IM |
1391 | list_add_rcu(&event->event_entry, &ctx->event_list); |
1392 | ctx->nr_events++; | |
1393 | if (event->attr.inherit_stat) | |
bfbd3381 | 1394 | ctx->nr_stat++; |
5a3126d4 PZ |
1395 | |
1396 | ctx->generation++; | |
04289bb9 IM |
1397 | } |
1398 | ||
0231bb53 JO |
1399 | /* |
1400 | * Initialize event state based on the perf_event_attr::disabled. | |
1401 | */ | |
1402 | static inline void perf_event__state_init(struct perf_event *event) | |
1403 | { | |
1404 | event->state = event->attr.disabled ? PERF_EVENT_STATE_OFF : | |
1405 | PERF_EVENT_STATE_INACTIVE; | |
1406 | } | |
1407 | ||
a723968c | 1408 | static void __perf_event_read_size(struct perf_event *event, int nr_siblings) |
c320c7b7 ACM |
1409 | { |
1410 | int entry = sizeof(u64); /* value */ | |
1411 | int size = 0; | |
1412 | int nr = 1; | |
1413 | ||
1414 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
1415 | size += sizeof(u64); | |
1416 | ||
1417 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
1418 | size += sizeof(u64); | |
1419 | ||
1420 | if (event->attr.read_format & PERF_FORMAT_ID) | |
1421 | entry += sizeof(u64); | |
1422 | ||
1423 | if (event->attr.read_format & PERF_FORMAT_GROUP) { | |
a723968c | 1424 | nr += nr_siblings; |
c320c7b7 ACM |
1425 | size += sizeof(u64); |
1426 | } | |
1427 | ||
1428 | size += entry * nr; | |
1429 | event->read_size = size; | |
1430 | } | |
1431 | ||
a723968c | 1432 | static void __perf_event_header_size(struct perf_event *event, u64 sample_type) |
c320c7b7 ACM |
1433 | { |
1434 | struct perf_sample_data *data; | |
c320c7b7 ACM |
1435 | u16 size = 0; |
1436 | ||
c320c7b7 ACM |
1437 | if (sample_type & PERF_SAMPLE_IP) |
1438 | size += sizeof(data->ip); | |
1439 | ||
6844c09d ACM |
1440 | if (sample_type & PERF_SAMPLE_ADDR) |
1441 | size += sizeof(data->addr); | |
1442 | ||
1443 | if (sample_type & PERF_SAMPLE_PERIOD) | |
1444 | size += sizeof(data->period); | |
1445 | ||
c3feedf2 AK |
1446 | if (sample_type & PERF_SAMPLE_WEIGHT) |
1447 | size += sizeof(data->weight); | |
1448 | ||
6844c09d ACM |
1449 | if (sample_type & PERF_SAMPLE_READ) |
1450 | size += event->read_size; | |
1451 | ||
d6be9ad6 SE |
1452 | if (sample_type & PERF_SAMPLE_DATA_SRC) |
1453 | size += sizeof(data->data_src.val); | |
1454 | ||
fdfbbd07 AK |
1455 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
1456 | size += sizeof(data->txn); | |
1457 | ||
6844c09d ACM |
1458 | event->header_size = size; |
1459 | } | |
1460 | ||
a723968c PZ |
1461 | /* |
1462 | * Called at perf_event creation and when events are attached/detached from a | |
1463 | * group. | |
1464 | */ | |
1465 | static void perf_event__header_size(struct perf_event *event) | |
1466 | { | |
1467 | __perf_event_read_size(event, | |
1468 | event->group_leader->nr_siblings); | |
1469 | __perf_event_header_size(event, event->attr.sample_type); | |
1470 | } | |
1471 | ||
6844c09d ACM |
1472 | static void perf_event__id_header_size(struct perf_event *event) |
1473 | { | |
1474 | struct perf_sample_data *data; | |
1475 | u64 sample_type = event->attr.sample_type; | |
1476 | u16 size = 0; | |
1477 | ||
c320c7b7 ACM |
1478 | if (sample_type & PERF_SAMPLE_TID) |
1479 | size += sizeof(data->tid_entry); | |
1480 | ||
1481 | if (sample_type & PERF_SAMPLE_TIME) | |
1482 | size += sizeof(data->time); | |
1483 | ||
ff3d527c AH |
1484 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
1485 | size += sizeof(data->id); | |
1486 | ||
c320c7b7 ACM |
1487 | if (sample_type & PERF_SAMPLE_ID) |
1488 | size += sizeof(data->id); | |
1489 | ||
1490 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
1491 | size += sizeof(data->stream_id); | |
1492 | ||
1493 | if (sample_type & PERF_SAMPLE_CPU) | |
1494 | size += sizeof(data->cpu_entry); | |
1495 | ||
6844c09d | 1496 | event->id_header_size = size; |
c320c7b7 ACM |
1497 | } |
1498 | ||
a723968c PZ |
1499 | static bool perf_event_validate_size(struct perf_event *event) |
1500 | { | |
1501 | /* | |
1502 | * The values computed here will be over-written when we actually | |
1503 | * attach the event. | |
1504 | */ | |
1505 | __perf_event_read_size(event, event->group_leader->nr_siblings + 1); | |
1506 | __perf_event_header_size(event, event->attr.sample_type & ~PERF_SAMPLE_READ); | |
1507 | perf_event__id_header_size(event); | |
1508 | ||
1509 | /* | |
1510 | * Sum the lot; should not exceed the 64k limit we have on records. | |
1511 | * Conservative limit to allow for callchains and other variable fields. | |
1512 | */ | |
1513 | if (event->read_size + event->header_size + | |
1514 | event->id_header_size + sizeof(struct perf_event_header) >= 16*1024) | |
1515 | return false; | |
1516 | ||
1517 | return true; | |
1518 | } | |
1519 | ||
8a49542c PZ |
1520 | static void perf_group_attach(struct perf_event *event) |
1521 | { | |
c320c7b7 | 1522 | struct perf_event *group_leader = event->group_leader, *pos; |
8a49542c | 1523 | |
74c3337c PZ |
1524 | /* |
1525 | * We can have double attach due to group movement in perf_event_open. | |
1526 | */ | |
1527 | if (event->attach_state & PERF_ATTACH_GROUP) | |
1528 | return; | |
1529 | ||
8a49542c PZ |
1530 | event->attach_state |= PERF_ATTACH_GROUP; |
1531 | ||
1532 | if (group_leader == event) | |
1533 | return; | |
1534 | ||
652884fe PZ |
1535 | WARN_ON_ONCE(group_leader->ctx != event->ctx); |
1536 | ||
8a49542c PZ |
1537 | if (group_leader->group_flags & PERF_GROUP_SOFTWARE && |
1538 | !is_software_event(event)) | |
1539 | group_leader->group_flags &= ~PERF_GROUP_SOFTWARE; | |
1540 | ||
1541 | list_add_tail(&event->group_entry, &group_leader->sibling_list); | |
1542 | group_leader->nr_siblings++; | |
c320c7b7 ACM |
1543 | |
1544 | perf_event__header_size(group_leader); | |
1545 | ||
1546 | list_for_each_entry(pos, &group_leader->sibling_list, group_entry) | |
1547 | perf_event__header_size(pos); | |
8a49542c PZ |
1548 | } |
1549 | ||
a63eaf34 | 1550 | /* |
cdd6c482 | 1551 | * Remove a event from the lists for its context. |
fccc714b | 1552 | * Must be called with ctx->mutex and ctx->lock held. |
a63eaf34 | 1553 | */ |
04289bb9 | 1554 | static void |
cdd6c482 | 1555 | list_del_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1556 | { |
68cacd29 | 1557 | struct perf_cpu_context *cpuctx; |
652884fe PZ |
1558 | |
1559 | WARN_ON_ONCE(event->ctx != ctx); | |
1560 | lockdep_assert_held(&ctx->lock); | |
1561 | ||
8a49542c PZ |
1562 | /* |
1563 | * We can have double detach due to exit/hot-unplug + close. | |
1564 | */ | |
1565 | if (!(event->attach_state & PERF_ATTACH_CONTEXT)) | |
a63eaf34 | 1566 | return; |
8a49542c PZ |
1567 | |
1568 | event->attach_state &= ~PERF_ATTACH_CONTEXT; | |
1569 | ||
68cacd29 | 1570 | if (is_cgroup_event(event)) { |
e5d1367f | 1571 | ctx->nr_cgroups--; |
70a01657 PZ |
1572 | /* |
1573 | * Because cgroup events are always per-cpu events, this will | |
1574 | * always be called from the right CPU. | |
1575 | */ | |
68cacd29 SE |
1576 | cpuctx = __get_cpu_context(ctx); |
1577 | /* | |
70a01657 PZ |
1578 | * If there are no more cgroup events then clear cgrp to avoid |
1579 | * stale pointer in update_cgrp_time_from_cpuctx(). | |
68cacd29 SE |
1580 | */ |
1581 | if (!ctx->nr_cgroups) | |
1582 | cpuctx->cgrp = NULL; | |
1583 | } | |
e5d1367f | 1584 | |
cdd6c482 IM |
1585 | ctx->nr_events--; |
1586 | if (event->attr.inherit_stat) | |
bfbd3381 | 1587 | ctx->nr_stat--; |
8bc20959 | 1588 | |
cdd6c482 | 1589 | list_del_rcu(&event->event_entry); |
04289bb9 | 1590 | |
8a49542c PZ |
1591 | if (event->group_leader == event) |
1592 | list_del_init(&event->group_entry); | |
5c148194 | 1593 | |
96c21a46 | 1594 | update_group_times(event); |
b2e74a26 SE |
1595 | |
1596 | /* | |
1597 | * If event was in error state, then keep it | |
1598 | * that way, otherwise bogus counts will be | |
1599 | * returned on read(). The only way to get out | |
1600 | * of error state is by explicit re-enabling | |
1601 | * of the event | |
1602 | */ | |
1603 | if (event->state > PERF_EVENT_STATE_OFF) | |
1604 | event->state = PERF_EVENT_STATE_OFF; | |
5a3126d4 PZ |
1605 | |
1606 | ctx->generation++; | |
050735b0 PZ |
1607 | } |
1608 | ||
8a49542c | 1609 | static void perf_group_detach(struct perf_event *event) |
050735b0 PZ |
1610 | { |
1611 | struct perf_event *sibling, *tmp; | |
8a49542c PZ |
1612 | struct list_head *list = NULL; |
1613 | ||
1614 | /* | |
1615 | * We can have double detach due to exit/hot-unplug + close. | |
1616 | */ | |
1617 | if (!(event->attach_state & PERF_ATTACH_GROUP)) | |
1618 | return; | |
1619 | ||
1620 | event->attach_state &= ~PERF_ATTACH_GROUP; | |
1621 | ||
1622 | /* | |
1623 | * If this is a sibling, remove it from its group. | |
1624 | */ | |
1625 | if (event->group_leader != event) { | |
1626 | list_del_init(&event->group_entry); | |
1627 | event->group_leader->nr_siblings--; | |
c320c7b7 | 1628 | goto out; |
8a49542c PZ |
1629 | } |
1630 | ||
1631 | if (!list_empty(&event->group_entry)) | |
1632 | list = &event->group_entry; | |
2e2af50b | 1633 | |
04289bb9 | 1634 | /* |
cdd6c482 IM |
1635 | * If this was a group event with sibling events then |
1636 | * upgrade the siblings to singleton events by adding them | |
8a49542c | 1637 | * to whatever list we are on. |
04289bb9 | 1638 | */ |
cdd6c482 | 1639 | list_for_each_entry_safe(sibling, tmp, &event->sibling_list, group_entry) { |
8a49542c PZ |
1640 | if (list) |
1641 | list_move_tail(&sibling->group_entry, list); | |
04289bb9 | 1642 | sibling->group_leader = sibling; |
d6f962b5 FW |
1643 | |
1644 | /* Inherit group flags from the previous leader */ | |
1645 | sibling->group_flags = event->group_flags; | |
652884fe PZ |
1646 | |
1647 | WARN_ON_ONCE(sibling->ctx != event->ctx); | |
04289bb9 | 1648 | } |
c320c7b7 ACM |
1649 | |
1650 | out: | |
1651 | perf_event__header_size(event->group_leader); | |
1652 | ||
1653 | list_for_each_entry(tmp, &event->group_leader->sibling_list, group_entry) | |
1654 | perf_event__header_size(tmp); | |
04289bb9 IM |
1655 | } |
1656 | ||
fadfe7be JO |
1657 | static bool is_orphaned_event(struct perf_event *event) |
1658 | { | |
a69b0ca4 | 1659 | return event->state == PERF_EVENT_STATE_DEAD; |
fadfe7be JO |
1660 | } |
1661 | ||
66eb579e MR |
1662 | static inline int pmu_filter_match(struct perf_event *event) |
1663 | { | |
1664 | struct pmu *pmu = event->pmu; | |
1665 | return pmu->filter_match ? pmu->filter_match(event) : 1; | |
1666 | } | |
1667 | ||
fa66f07a SE |
1668 | static inline int |
1669 | event_filter_match(struct perf_event *event) | |
1670 | { | |
e5d1367f | 1671 | return (event->cpu == -1 || event->cpu == smp_processor_id()) |
66eb579e | 1672 | && perf_cgroup_match(event) && pmu_filter_match(event); |
fa66f07a SE |
1673 | } |
1674 | ||
9ffcfa6f SE |
1675 | static void |
1676 | event_sched_out(struct perf_event *event, | |
3b6f9e5c | 1677 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 1678 | struct perf_event_context *ctx) |
3b6f9e5c | 1679 | { |
4158755d | 1680 | u64 tstamp = perf_event_time(event); |
fa66f07a | 1681 | u64 delta; |
652884fe PZ |
1682 | |
1683 | WARN_ON_ONCE(event->ctx != ctx); | |
1684 | lockdep_assert_held(&ctx->lock); | |
1685 | ||
fa66f07a SE |
1686 | /* |
1687 | * An event which could not be activated because of | |
1688 | * filter mismatch still needs to have its timings | |
1689 | * maintained, otherwise bogus information is return | |
1690 | * via read() for time_enabled, time_running: | |
1691 | */ | |
1692 | if (event->state == PERF_EVENT_STATE_INACTIVE | |
1693 | && !event_filter_match(event)) { | |
e5d1367f | 1694 | delta = tstamp - event->tstamp_stopped; |
fa66f07a | 1695 | event->tstamp_running += delta; |
4158755d | 1696 | event->tstamp_stopped = tstamp; |
fa66f07a SE |
1697 | } |
1698 | ||
cdd6c482 | 1699 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
9ffcfa6f | 1700 | return; |
3b6f9e5c | 1701 | |
44377277 AS |
1702 | perf_pmu_disable(event->pmu); |
1703 | ||
28a967c3 PZ |
1704 | event->tstamp_stopped = tstamp; |
1705 | event->pmu->del(event, 0); | |
1706 | event->oncpu = -1; | |
cdd6c482 IM |
1707 | event->state = PERF_EVENT_STATE_INACTIVE; |
1708 | if (event->pending_disable) { | |
1709 | event->pending_disable = 0; | |
1710 | event->state = PERF_EVENT_STATE_OFF; | |
970892a9 | 1711 | } |
3b6f9e5c | 1712 | |
cdd6c482 | 1713 | if (!is_software_event(event)) |
3b6f9e5c | 1714 | cpuctx->active_oncpu--; |
2fde4f94 MR |
1715 | if (!--ctx->nr_active) |
1716 | perf_event_ctx_deactivate(ctx); | |
0f5a2601 PZ |
1717 | if (event->attr.freq && event->attr.sample_freq) |
1718 | ctx->nr_freq--; | |
cdd6c482 | 1719 | if (event->attr.exclusive || !cpuctx->active_oncpu) |
3b6f9e5c | 1720 | cpuctx->exclusive = 0; |
44377277 AS |
1721 | |
1722 | perf_pmu_enable(event->pmu); | |
3b6f9e5c PM |
1723 | } |
1724 | ||
d859e29f | 1725 | static void |
cdd6c482 | 1726 | group_sched_out(struct perf_event *group_event, |
d859e29f | 1727 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 1728 | struct perf_event_context *ctx) |
d859e29f | 1729 | { |
cdd6c482 | 1730 | struct perf_event *event; |
fa66f07a | 1731 | int state = group_event->state; |
d859e29f | 1732 | |
cdd6c482 | 1733 | event_sched_out(group_event, cpuctx, ctx); |
d859e29f PM |
1734 | |
1735 | /* | |
1736 | * Schedule out siblings (if any): | |
1737 | */ | |
cdd6c482 IM |
1738 | list_for_each_entry(event, &group_event->sibling_list, group_entry) |
1739 | event_sched_out(event, cpuctx, ctx); | |
d859e29f | 1740 | |
fa66f07a | 1741 | if (state == PERF_EVENT_STATE_ACTIVE && group_event->attr.exclusive) |
d859e29f PM |
1742 | cpuctx->exclusive = 0; |
1743 | } | |
1744 | ||
45a0e07a | 1745 | #define DETACH_GROUP 0x01UL |
0017960f | 1746 | |
0793a61d | 1747 | /* |
cdd6c482 | 1748 | * Cross CPU call to remove a performance event |
0793a61d | 1749 | * |
cdd6c482 | 1750 | * We disable the event on the hardware level first. After that we |
0793a61d TG |
1751 | * remove it from the context list. |
1752 | */ | |
fae3fde6 PZ |
1753 | static void |
1754 | __perf_remove_from_context(struct perf_event *event, | |
1755 | struct perf_cpu_context *cpuctx, | |
1756 | struct perf_event_context *ctx, | |
1757 | void *info) | |
0793a61d | 1758 | { |
45a0e07a | 1759 | unsigned long flags = (unsigned long)info; |
0793a61d | 1760 | |
cdd6c482 | 1761 | event_sched_out(event, cpuctx, ctx); |
45a0e07a | 1762 | if (flags & DETACH_GROUP) |
46ce0fe9 | 1763 | perf_group_detach(event); |
cdd6c482 | 1764 | list_del_event(event, ctx); |
39a43640 PZ |
1765 | |
1766 | if (!ctx->nr_events && ctx->is_active) { | |
64ce3126 | 1767 | ctx->is_active = 0; |
39a43640 PZ |
1768 | if (ctx->task) { |
1769 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
1770 | cpuctx->task_ctx = NULL; | |
1771 | } | |
64ce3126 | 1772 | } |
0793a61d TG |
1773 | } |
1774 | ||
0793a61d | 1775 | /* |
cdd6c482 | 1776 | * Remove the event from a task's (or a CPU's) list of events. |
0793a61d | 1777 | * |
cdd6c482 IM |
1778 | * If event->ctx is a cloned context, callers must make sure that |
1779 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 PM |
1780 | * remains valid. This is OK when called from perf_release since |
1781 | * that only calls us on the top-level context, which can't be a clone. | |
cdd6c482 | 1782 | * When called from perf_event_exit_task, it's OK because the |
c93f7669 | 1783 | * context has been detached from its task. |
0793a61d | 1784 | */ |
45a0e07a | 1785 | static void perf_remove_from_context(struct perf_event *event, unsigned long flags) |
0793a61d | 1786 | { |
fae3fde6 | 1787 | lockdep_assert_held(&event->ctx->mutex); |
0793a61d | 1788 | |
45a0e07a | 1789 | event_function_call(event, __perf_remove_from_context, (void *)flags); |
0793a61d TG |
1790 | } |
1791 | ||
d859e29f | 1792 | /* |
cdd6c482 | 1793 | * Cross CPU call to disable a performance event |
d859e29f | 1794 | */ |
fae3fde6 PZ |
1795 | static void __perf_event_disable(struct perf_event *event, |
1796 | struct perf_cpu_context *cpuctx, | |
1797 | struct perf_event_context *ctx, | |
1798 | void *info) | |
7b648018 | 1799 | { |
fae3fde6 PZ |
1800 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
1801 | return; | |
7b648018 | 1802 | |
fae3fde6 PZ |
1803 | update_context_time(ctx); |
1804 | update_cgrp_time_from_event(event); | |
1805 | update_group_times(event); | |
1806 | if (event == event->group_leader) | |
1807 | group_sched_out(event, cpuctx, ctx); | |
1808 | else | |
1809 | event_sched_out(event, cpuctx, ctx); | |
1810 | event->state = PERF_EVENT_STATE_OFF; | |
7b648018 PZ |
1811 | } |
1812 | ||
d859e29f | 1813 | /* |
cdd6c482 | 1814 | * Disable a event. |
c93f7669 | 1815 | * |
cdd6c482 IM |
1816 | * If event->ctx is a cloned context, callers must make sure that |
1817 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 1818 | * remains valid. This condition is satisifed when called through |
cdd6c482 IM |
1819 | * perf_event_for_each_child or perf_event_for_each because they |
1820 | * hold the top-level event's child_mutex, so any descendant that | |
8ba289b8 PZ |
1821 | * goes to exit will block in perf_event_exit_event(). |
1822 | * | |
cdd6c482 | 1823 | * When called from perf_pending_event it's OK because event->ctx |
c93f7669 | 1824 | * is the current context on this CPU and preemption is disabled, |
cdd6c482 | 1825 | * hence we can't get into perf_event_task_sched_out for this context. |
d859e29f | 1826 | */ |
f63a8daa | 1827 | static void _perf_event_disable(struct perf_event *event) |
d859e29f | 1828 | { |
cdd6c482 | 1829 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 1830 | |
e625cce1 | 1831 | raw_spin_lock_irq(&ctx->lock); |
7b648018 | 1832 | if (event->state <= PERF_EVENT_STATE_OFF) { |
e625cce1 | 1833 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 1834 | return; |
53cfbf59 | 1835 | } |
e625cce1 | 1836 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 1837 | |
fae3fde6 PZ |
1838 | event_function_call(event, __perf_event_disable, NULL); |
1839 | } | |
1840 | ||
1841 | void perf_event_disable_local(struct perf_event *event) | |
1842 | { | |
1843 | event_function_local(event, __perf_event_disable, NULL); | |
d859e29f | 1844 | } |
f63a8daa PZ |
1845 | |
1846 | /* | |
1847 | * Strictly speaking kernel users cannot create groups and therefore this | |
1848 | * interface does not need the perf_event_ctx_lock() magic. | |
1849 | */ | |
1850 | void perf_event_disable(struct perf_event *event) | |
1851 | { | |
1852 | struct perf_event_context *ctx; | |
1853 | ||
1854 | ctx = perf_event_ctx_lock(event); | |
1855 | _perf_event_disable(event); | |
1856 | perf_event_ctx_unlock(event, ctx); | |
1857 | } | |
dcfce4a0 | 1858 | EXPORT_SYMBOL_GPL(perf_event_disable); |
d859e29f | 1859 | |
e5d1367f SE |
1860 | static void perf_set_shadow_time(struct perf_event *event, |
1861 | struct perf_event_context *ctx, | |
1862 | u64 tstamp) | |
1863 | { | |
1864 | /* | |
1865 | * use the correct time source for the time snapshot | |
1866 | * | |
1867 | * We could get by without this by leveraging the | |
1868 | * fact that to get to this function, the caller | |
1869 | * has most likely already called update_context_time() | |
1870 | * and update_cgrp_time_xx() and thus both timestamp | |
1871 | * are identical (or very close). Given that tstamp is, | |
1872 | * already adjusted for cgroup, we could say that: | |
1873 | * tstamp - ctx->timestamp | |
1874 | * is equivalent to | |
1875 | * tstamp - cgrp->timestamp. | |
1876 | * | |
1877 | * Then, in perf_output_read(), the calculation would | |
1878 | * work with no changes because: | |
1879 | * - event is guaranteed scheduled in | |
1880 | * - no scheduled out in between | |
1881 | * - thus the timestamp would be the same | |
1882 | * | |
1883 | * But this is a bit hairy. | |
1884 | * | |
1885 | * So instead, we have an explicit cgroup call to remain | |
1886 | * within the time time source all along. We believe it | |
1887 | * is cleaner and simpler to understand. | |
1888 | */ | |
1889 | if (is_cgroup_event(event)) | |
1890 | perf_cgroup_set_shadow_time(event, tstamp); | |
1891 | else | |
1892 | event->shadow_ctx_time = tstamp - ctx->timestamp; | |
1893 | } | |
1894 | ||
4fe757dd PZ |
1895 | #define MAX_INTERRUPTS (~0ULL) |
1896 | ||
1897 | static void perf_log_throttle(struct perf_event *event, int enable); | |
ec0d7729 | 1898 | static void perf_log_itrace_start(struct perf_event *event); |
4fe757dd | 1899 | |
235c7fc7 | 1900 | static int |
9ffcfa6f | 1901 | event_sched_in(struct perf_event *event, |
235c7fc7 | 1902 | struct perf_cpu_context *cpuctx, |
6e37738a | 1903 | struct perf_event_context *ctx) |
235c7fc7 | 1904 | { |
4158755d | 1905 | u64 tstamp = perf_event_time(event); |
44377277 | 1906 | int ret = 0; |
4158755d | 1907 | |
63342411 PZ |
1908 | lockdep_assert_held(&ctx->lock); |
1909 | ||
cdd6c482 | 1910 | if (event->state <= PERF_EVENT_STATE_OFF) |
235c7fc7 IM |
1911 | return 0; |
1912 | ||
cdd6c482 | 1913 | event->state = PERF_EVENT_STATE_ACTIVE; |
6e37738a | 1914 | event->oncpu = smp_processor_id(); |
4fe757dd PZ |
1915 | |
1916 | /* | |
1917 | * Unthrottle events, since we scheduled we might have missed several | |
1918 | * ticks already, also for a heavily scheduling task there is little | |
1919 | * guarantee it'll get a tick in a timely manner. | |
1920 | */ | |
1921 | if (unlikely(event->hw.interrupts == MAX_INTERRUPTS)) { | |
1922 | perf_log_throttle(event, 1); | |
1923 | event->hw.interrupts = 0; | |
1924 | } | |
1925 | ||
235c7fc7 IM |
1926 | /* |
1927 | * The new state must be visible before we turn it on in the hardware: | |
1928 | */ | |
1929 | smp_wmb(); | |
1930 | ||
44377277 AS |
1931 | perf_pmu_disable(event->pmu); |
1932 | ||
72f669c0 SL |
1933 | perf_set_shadow_time(event, ctx, tstamp); |
1934 | ||
ec0d7729 AS |
1935 | perf_log_itrace_start(event); |
1936 | ||
a4eaf7f1 | 1937 | if (event->pmu->add(event, PERF_EF_START)) { |
cdd6c482 IM |
1938 | event->state = PERF_EVENT_STATE_INACTIVE; |
1939 | event->oncpu = -1; | |
44377277 AS |
1940 | ret = -EAGAIN; |
1941 | goto out; | |
235c7fc7 IM |
1942 | } |
1943 | ||
00a2916f PZ |
1944 | event->tstamp_running += tstamp - event->tstamp_stopped; |
1945 | ||
cdd6c482 | 1946 | if (!is_software_event(event)) |
3b6f9e5c | 1947 | cpuctx->active_oncpu++; |
2fde4f94 MR |
1948 | if (!ctx->nr_active++) |
1949 | perf_event_ctx_activate(ctx); | |
0f5a2601 PZ |
1950 | if (event->attr.freq && event->attr.sample_freq) |
1951 | ctx->nr_freq++; | |
235c7fc7 | 1952 | |
cdd6c482 | 1953 | if (event->attr.exclusive) |
3b6f9e5c PM |
1954 | cpuctx->exclusive = 1; |
1955 | ||
44377277 AS |
1956 | out: |
1957 | perf_pmu_enable(event->pmu); | |
1958 | ||
1959 | return ret; | |
235c7fc7 IM |
1960 | } |
1961 | ||
6751b71e | 1962 | static int |
cdd6c482 | 1963 | group_sched_in(struct perf_event *group_event, |
6751b71e | 1964 | struct perf_cpu_context *cpuctx, |
6e37738a | 1965 | struct perf_event_context *ctx) |
6751b71e | 1966 | { |
6bde9b6c | 1967 | struct perf_event *event, *partial_group = NULL; |
4a234593 | 1968 | struct pmu *pmu = ctx->pmu; |
d7842da4 SE |
1969 | u64 now = ctx->time; |
1970 | bool simulate = false; | |
6751b71e | 1971 | |
cdd6c482 | 1972 | if (group_event->state == PERF_EVENT_STATE_OFF) |
6751b71e PM |
1973 | return 0; |
1974 | ||
fbbe0701 | 1975 | pmu->start_txn(pmu, PERF_PMU_TXN_ADD); |
6bde9b6c | 1976 | |
9ffcfa6f | 1977 | if (event_sched_in(group_event, cpuctx, ctx)) { |
ad5133b7 | 1978 | pmu->cancel_txn(pmu); |
272325c4 | 1979 | perf_mux_hrtimer_restart(cpuctx); |
6751b71e | 1980 | return -EAGAIN; |
90151c35 | 1981 | } |
6751b71e PM |
1982 | |
1983 | /* | |
1984 | * Schedule in siblings as one group (if any): | |
1985 | */ | |
cdd6c482 | 1986 | list_for_each_entry(event, &group_event->sibling_list, group_entry) { |
9ffcfa6f | 1987 | if (event_sched_in(event, cpuctx, ctx)) { |
cdd6c482 | 1988 | partial_group = event; |
6751b71e PM |
1989 | goto group_error; |
1990 | } | |
1991 | } | |
1992 | ||
9ffcfa6f | 1993 | if (!pmu->commit_txn(pmu)) |
6e85158c | 1994 | return 0; |
9ffcfa6f | 1995 | |
6751b71e PM |
1996 | group_error: |
1997 | /* | |
1998 | * Groups can be scheduled in as one unit only, so undo any | |
1999 | * partial group before returning: | |
d7842da4 SE |
2000 | * The events up to the failed event are scheduled out normally, |
2001 | * tstamp_stopped will be updated. | |
2002 | * | |
2003 | * The failed events and the remaining siblings need to have | |
2004 | * their timings updated as if they had gone thru event_sched_in() | |
2005 | * and event_sched_out(). This is required to get consistent timings | |
2006 | * across the group. This also takes care of the case where the group | |
2007 | * could never be scheduled by ensuring tstamp_stopped is set to mark | |
2008 | * the time the event was actually stopped, such that time delta | |
2009 | * calculation in update_event_times() is correct. | |
6751b71e | 2010 | */ |
cdd6c482 IM |
2011 | list_for_each_entry(event, &group_event->sibling_list, group_entry) { |
2012 | if (event == partial_group) | |
d7842da4 SE |
2013 | simulate = true; |
2014 | ||
2015 | if (simulate) { | |
2016 | event->tstamp_running += now - event->tstamp_stopped; | |
2017 | event->tstamp_stopped = now; | |
2018 | } else { | |
2019 | event_sched_out(event, cpuctx, ctx); | |
2020 | } | |
6751b71e | 2021 | } |
9ffcfa6f | 2022 | event_sched_out(group_event, cpuctx, ctx); |
6751b71e | 2023 | |
ad5133b7 | 2024 | pmu->cancel_txn(pmu); |
90151c35 | 2025 | |
272325c4 | 2026 | perf_mux_hrtimer_restart(cpuctx); |
9e630205 | 2027 | |
6751b71e PM |
2028 | return -EAGAIN; |
2029 | } | |
2030 | ||
3b6f9e5c | 2031 | /* |
cdd6c482 | 2032 | * Work out whether we can put this event group on the CPU now. |
3b6f9e5c | 2033 | */ |
cdd6c482 | 2034 | static int group_can_go_on(struct perf_event *event, |
3b6f9e5c PM |
2035 | struct perf_cpu_context *cpuctx, |
2036 | int can_add_hw) | |
2037 | { | |
2038 | /* | |
cdd6c482 | 2039 | * Groups consisting entirely of software events can always go on. |
3b6f9e5c | 2040 | */ |
d6f962b5 | 2041 | if (event->group_flags & PERF_GROUP_SOFTWARE) |
3b6f9e5c PM |
2042 | return 1; |
2043 | /* | |
2044 | * If an exclusive group is already on, no other hardware | |
cdd6c482 | 2045 | * events can go on. |
3b6f9e5c PM |
2046 | */ |
2047 | if (cpuctx->exclusive) | |
2048 | return 0; | |
2049 | /* | |
2050 | * If this group is exclusive and there are already | |
cdd6c482 | 2051 | * events on the CPU, it can't go on. |
3b6f9e5c | 2052 | */ |
cdd6c482 | 2053 | if (event->attr.exclusive && cpuctx->active_oncpu) |
3b6f9e5c PM |
2054 | return 0; |
2055 | /* | |
2056 | * Otherwise, try to add it if all previous groups were able | |
2057 | * to go on. | |
2058 | */ | |
2059 | return can_add_hw; | |
2060 | } | |
2061 | ||
cdd6c482 IM |
2062 | static void add_event_to_ctx(struct perf_event *event, |
2063 | struct perf_event_context *ctx) | |
53cfbf59 | 2064 | { |
4158755d SE |
2065 | u64 tstamp = perf_event_time(event); |
2066 | ||
cdd6c482 | 2067 | list_add_event(event, ctx); |
8a49542c | 2068 | perf_group_attach(event); |
4158755d SE |
2069 | event->tstamp_enabled = tstamp; |
2070 | event->tstamp_running = tstamp; | |
2071 | event->tstamp_stopped = tstamp; | |
53cfbf59 PM |
2072 | } |
2073 | ||
bd2afa49 PZ |
2074 | static void ctx_sched_out(struct perf_event_context *ctx, |
2075 | struct perf_cpu_context *cpuctx, | |
2076 | enum event_type_t event_type); | |
2c29ef0f PZ |
2077 | static void |
2078 | ctx_sched_in(struct perf_event_context *ctx, | |
2079 | struct perf_cpu_context *cpuctx, | |
2080 | enum event_type_t event_type, | |
2081 | struct task_struct *task); | |
fe4b04fa | 2082 | |
bd2afa49 PZ |
2083 | static void task_ctx_sched_out(struct perf_cpu_context *cpuctx, |
2084 | struct perf_event_context *ctx) | |
2085 | { | |
2086 | if (!cpuctx->task_ctx) | |
2087 | return; | |
2088 | ||
2089 | if (WARN_ON_ONCE(ctx != cpuctx->task_ctx)) | |
2090 | return; | |
2091 | ||
2092 | ctx_sched_out(ctx, cpuctx, EVENT_ALL); | |
2093 | } | |
2094 | ||
dce5855b PZ |
2095 | static void perf_event_sched_in(struct perf_cpu_context *cpuctx, |
2096 | struct perf_event_context *ctx, | |
2097 | struct task_struct *task) | |
2098 | { | |
2099 | cpu_ctx_sched_in(cpuctx, EVENT_PINNED, task); | |
2100 | if (ctx) | |
2101 | ctx_sched_in(ctx, cpuctx, EVENT_PINNED, task); | |
2102 | cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE, task); | |
2103 | if (ctx) | |
2104 | ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE, task); | |
2105 | } | |
2106 | ||
3e349507 PZ |
2107 | static void ctx_resched(struct perf_cpu_context *cpuctx, |
2108 | struct perf_event_context *task_ctx) | |
0017960f | 2109 | { |
3e349507 PZ |
2110 | perf_pmu_disable(cpuctx->ctx.pmu); |
2111 | if (task_ctx) | |
2112 | task_ctx_sched_out(cpuctx, task_ctx); | |
2113 | cpu_ctx_sched_out(cpuctx, EVENT_ALL); | |
2114 | perf_event_sched_in(cpuctx, task_ctx, current); | |
2115 | perf_pmu_enable(cpuctx->ctx.pmu); | |
0017960f PZ |
2116 | } |
2117 | ||
0793a61d | 2118 | /* |
cdd6c482 | 2119 | * Cross CPU call to install and enable a performance event |
682076ae | 2120 | * |
a096309b PZ |
2121 | * Very similar to remote_function() + event_function() but cannot assume that |
2122 | * things like ctx->is_active and cpuctx->task_ctx are set. | |
0793a61d | 2123 | */ |
fe4b04fa | 2124 | static int __perf_install_in_context(void *info) |
0793a61d | 2125 | { |
a096309b PZ |
2126 | struct perf_event *event = info; |
2127 | struct perf_event_context *ctx = event->ctx; | |
108b02cf | 2128 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
2c29ef0f | 2129 | struct perf_event_context *task_ctx = cpuctx->task_ctx; |
a096309b PZ |
2130 | bool activate = true; |
2131 | int ret = 0; | |
0793a61d | 2132 | |
63b6da39 | 2133 | raw_spin_lock(&cpuctx->ctx.lock); |
39a43640 | 2134 | if (ctx->task) { |
b58f6b0d PZ |
2135 | raw_spin_lock(&ctx->lock); |
2136 | task_ctx = ctx; | |
a096309b PZ |
2137 | |
2138 | /* If we're on the wrong CPU, try again */ | |
2139 | if (task_cpu(ctx->task) != smp_processor_id()) { | |
2140 | ret = -ESRCH; | |
63b6da39 | 2141 | goto unlock; |
a096309b | 2142 | } |
b58f6b0d | 2143 | |
39a43640 | 2144 | /* |
a096309b PZ |
2145 | * If we're on the right CPU, see if the task we target is |
2146 | * current, if not we don't have to activate the ctx, a future | |
2147 | * context switch will do that for us. | |
39a43640 | 2148 | */ |
a096309b PZ |
2149 | if (ctx->task != current) |
2150 | activate = false; | |
2151 | else | |
2152 | WARN_ON_ONCE(cpuctx->task_ctx && cpuctx->task_ctx != ctx); | |
2153 | ||
63b6da39 PZ |
2154 | } else if (task_ctx) { |
2155 | raw_spin_lock(&task_ctx->lock); | |
2c29ef0f | 2156 | } |
b58f6b0d | 2157 | |
a096309b PZ |
2158 | if (activate) { |
2159 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); | |
2160 | add_event_to_ctx(event, ctx); | |
2161 | ctx_resched(cpuctx, task_ctx); | |
2162 | } else { | |
2163 | add_event_to_ctx(event, ctx); | |
2164 | } | |
2165 | ||
63b6da39 | 2166 | unlock: |
2c29ef0f | 2167 | perf_ctx_unlock(cpuctx, task_ctx); |
fe4b04fa | 2168 | |
a096309b | 2169 | return ret; |
0793a61d TG |
2170 | } |
2171 | ||
2172 | /* | |
a096309b PZ |
2173 | * Attach a performance event to a context. |
2174 | * | |
2175 | * Very similar to event_function_call, see comment there. | |
0793a61d TG |
2176 | */ |
2177 | static void | |
cdd6c482 IM |
2178 | perf_install_in_context(struct perf_event_context *ctx, |
2179 | struct perf_event *event, | |
0793a61d TG |
2180 | int cpu) |
2181 | { | |
a096309b | 2182 | struct task_struct *task = READ_ONCE(ctx->task); |
39a43640 | 2183 | |
fe4b04fa PZ |
2184 | lockdep_assert_held(&ctx->mutex); |
2185 | ||
c3f00c70 | 2186 | event->ctx = ctx; |
0cda4c02 YZ |
2187 | if (event->cpu != -1) |
2188 | event->cpu = cpu; | |
c3f00c70 | 2189 | |
a096309b PZ |
2190 | if (!task) { |
2191 | cpu_function_call(cpu, __perf_install_in_context, event); | |
2192 | return; | |
2193 | } | |
2194 | ||
2195 | /* | |
2196 | * Should not happen, we validate the ctx is still alive before calling. | |
2197 | */ | |
2198 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) | |
2199 | return; | |
2200 | ||
39a43640 PZ |
2201 | /* |
2202 | * Installing events is tricky because we cannot rely on ctx->is_active | |
2203 | * to be set in case this is the nr_events 0 -> 1 transition. | |
39a43640 | 2204 | */ |
a096309b | 2205 | again: |
63b6da39 | 2206 | /* |
a096309b PZ |
2207 | * Cannot use task_function_call() because we need to run on the task's |
2208 | * CPU regardless of whether its current or not. | |
63b6da39 | 2209 | */ |
a096309b PZ |
2210 | if (!cpu_function_call(task_cpu(task), __perf_install_in_context, event)) |
2211 | return; | |
2212 | ||
2213 | raw_spin_lock_irq(&ctx->lock); | |
2214 | task = ctx->task; | |
84c4e620 | 2215 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) { |
a096309b PZ |
2216 | /* |
2217 | * Cannot happen because we already checked above (which also | |
2218 | * cannot happen), and we hold ctx->mutex, which serializes us | |
2219 | * against perf_event_exit_task_context(). | |
2220 | */ | |
63b6da39 PZ |
2221 | raw_spin_unlock_irq(&ctx->lock); |
2222 | return; | |
2223 | } | |
39a43640 | 2224 | raw_spin_unlock_irq(&ctx->lock); |
39a43640 | 2225 | /* |
a096309b PZ |
2226 | * Since !ctx->is_active doesn't mean anything, we must IPI |
2227 | * unconditionally. | |
39a43640 | 2228 | */ |
a096309b | 2229 | goto again; |
0793a61d TG |
2230 | } |
2231 | ||
fa289bec | 2232 | /* |
cdd6c482 | 2233 | * Put a event into inactive state and update time fields. |
fa289bec PM |
2234 | * Enabling the leader of a group effectively enables all |
2235 | * the group members that aren't explicitly disabled, so we | |
2236 | * have to update their ->tstamp_enabled also. | |
2237 | * Note: this works for group members as well as group leaders | |
2238 | * since the non-leader members' sibling_lists will be empty. | |
2239 | */ | |
1d9b482e | 2240 | static void __perf_event_mark_enabled(struct perf_event *event) |
fa289bec | 2241 | { |
cdd6c482 | 2242 | struct perf_event *sub; |
4158755d | 2243 | u64 tstamp = perf_event_time(event); |
fa289bec | 2244 | |
cdd6c482 | 2245 | event->state = PERF_EVENT_STATE_INACTIVE; |
4158755d | 2246 | event->tstamp_enabled = tstamp - event->total_time_enabled; |
9ed6060d | 2247 | list_for_each_entry(sub, &event->sibling_list, group_entry) { |
4158755d SE |
2248 | if (sub->state >= PERF_EVENT_STATE_INACTIVE) |
2249 | sub->tstamp_enabled = tstamp - sub->total_time_enabled; | |
9ed6060d | 2250 | } |
fa289bec PM |
2251 | } |
2252 | ||
d859e29f | 2253 | /* |
cdd6c482 | 2254 | * Cross CPU call to enable a performance event |
d859e29f | 2255 | */ |
fae3fde6 PZ |
2256 | static void __perf_event_enable(struct perf_event *event, |
2257 | struct perf_cpu_context *cpuctx, | |
2258 | struct perf_event_context *ctx, | |
2259 | void *info) | |
04289bb9 | 2260 | { |
cdd6c482 | 2261 | struct perf_event *leader = event->group_leader; |
fae3fde6 | 2262 | struct perf_event_context *task_ctx; |
04289bb9 | 2263 | |
6e801e01 PZ |
2264 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2265 | event->state <= PERF_EVENT_STATE_ERROR) | |
fae3fde6 | 2266 | return; |
3cbed429 | 2267 | |
bd2afa49 PZ |
2268 | if (ctx->is_active) |
2269 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); | |
2270 | ||
1d9b482e | 2271 | __perf_event_mark_enabled(event); |
04289bb9 | 2272 | |
fae3fde6 PZ |
2273 | if (!ctx->is_active) |
2274 | return; | |
2275 | ||
e5d1367f | 2276 | if (!event_filter_match(event)) { |
bd2afa49 | 2277 | if (is_cgroup_event(event)) |
e5d1367f | 2278 | perf_cgroup_defer_enabled(event); |
bd2afa49 | 2279 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); |
fae3fde6 | 2280 | return; |
e5d1367f | 2281 | } |
f4c4176f | 2282 | |
04289bb9 | 2283 | /* |
cdd6c482 | 2284 | * If the event is in a group and isn't the group leader, |
d859e29f | 2285 | * then don't put it on unless the group is on. |
04289bb9 | 2286 | */ |
bd2afa49 PZ |
2287 | if (leader != event && leader->state != PERF_EVENT_STATE_ACTIVE) { |
2288 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
fae3fde6 | 2289 | return; |
bd2afa49 | 2290 | } |
fe4b04fa | 2291 | |
fae3fde6 PZ |
2292 | task_ctx = cpuctx->task_ctx; |
2293 | if (ctx->task) | |
2294 | WARN_ON_ONCE(task_ctx != ctx); | |
d859e29f | 2295 | |
fae3fde6 | 2296 | ctx_resched(cpuctx, task_ctx); |
7b648018 PZ |
2297 | } |
2298 | ||
d859e29f | 2299 | /* |
cdd6c482 | 2300 | * Enable a event. |
c93f7669 | 2301 | * |
cdd6c482 IM |
2302 | * If event->ctx is a cloned context, callers must make sure that |
2303 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 2304 | * remains valid. This condition is satisfied when called through |
cdd6c482 IM |
2305 | * perf_event_for_each_child or perf_event_for_each as described |
2306 | * for perf_event_disable. | |
d859e29f | 2307 | */ |
f63a8daa | 2308 | static void _perf_event_enable(struct perf_event *event) |
d859e29f | 2309 | { |
cdd6c482 | 2310 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 2311 | |
7b648018 | 2312 | raw_spin_lock_irq(&ctx->lock); |
6e801e01 PZ |
2313 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2314 | event->state < PERF_EVENT_STATE_ERROR) { | |
7b648018 | 2315 | raw_spin_unlock_irq(&ctx->lock); |
d859e29f PM |
2316 | return; |
2317 | } | |
2318 | ||
d859e29f | 2319 | /* |
cdd6c482 | 2320 | * If the event is in error state, clear that first. |
7b648018 PZ |
2321 | * |
2322 | * That way, if we see the event in error state below, we know that it | |
2323 | * has gone back into error state, as distinct from the task having | |
2324 | * been scheduled away before the cross-call arrived. | |
d859e29f | 2325 | */ |
cdd6c482 IM |
2326 | if (event->state == PERF_EVENT_STATE_ERROR) |
2327 | event->state = PERF_EVENT_STATE_OFF; | |
e625cce1 | 2328 | raw_spin_unlock_irq(&ctx->lock); |
fe4b04fa | 2329 | |
fae3fde6 | 2330 | event_function_call(event, __perf_event_enable, NULL); |
d859e29f | 2331 | } |
f63a8daa PZ |
2332 | |
2333 | /* | |
2334 | * See perf_event_disable(); | |
2335 | */ | |
2336 | void perf_event_enable(struct perf_event *event) | |
2337 | { | |
2338 | struct perf_event_context *ctx; | |
2339 | ||
2340 | ctx = perf_event_ctx_lock(event); | |
2341 | _perf_event_enable(event); | |
2342 | perf_event_ctx_unlock(event, ctx); | |
2343 | } | |
dcfce4a0 | 2344 | EXPORT_SYMBOL_GPL(perf_event_enable); |
d859e29f | 2345 | |
f63a8daa | 2346 | static int _perf_event_refresh(struct perf_event *event, int refresh) |
79f14641 | 2347 | { |
2023b359 | 2348 | /* |
cdd6c482 | 2349 | * not supported on inherited events |
2023b359 | 2350 | */ |
2e939d1d | 2351 | if (event->attr.inherit || !is_sampling_event(event)) |
2023b359 PZ |
2352 | return -EINVAL; |
2353 | ||
cdd6c482 | 2354 | atomic_add(refresh, &event->event_limit); |
f63a8daa | 2355 | _perf_event_enable(event); |
2023b359 PZ |
2356 | |
2357 | return 0; | |
79f14641 | 2358 | } |
f63a8daa PZ |
2359 | |
2360 | /* | |
2361 | * See perf_event_disable() | |
2362 | */ | |
2363 | int perf_event_refresh(struct perf_event *event, int refresh) | |
2364 | { | |
2365 | struct perf_event_context *ctx; | |
2366 | int ret; | |
2367 | ||
2368 | ctx = perf_event_ctx_lock(event); | |
2369 | ret = _perf_event_refresh(event, refresh); | |
2370 | perf_event_ctx_unlock(event, ctx); | |
2371 | ||
2372 | return ret; | |
2373 | } | |
26ca5c11 | 2374 | EXPORT_SYMBOL_GPL(perf_event_refresh); |
79f14641 | 2375 | |
5b0311e1 FW |
2376 | static void ctx_sched_out(struct perf_event_context *ctx, |
2377 | struct perf_cpu_context *cpuctx, | |
2378 | enum event_type_t event_type) | |
235c7fc7 | 2379 | { |
db24d33e | 2380 | int is_active = ctx->is_active; |
c994d613 | 2381 | struct perf_event *event; |
235c7fc7 | 2382 | |
c994d613 | 2383 | lockdep_assert_held(&ctx->lock); |
235c7fc7 | 2384 | |
39a43640 PZ |
2385 | if (likely(!ctx->nr_events)) { |
2386 | /* | |
2387 | * See __perf_remove_from_context(). | |
2388 | */ | |
2389 | WARN_ON_ONCE(ctx->is_active); | |
2390 | if (ctx->task) | |
2391 | WARN_ON_ONCE(cpuctx->task_ctx); | |
facc4307 | 2392 | return; |
39a43640 PZ |
2393 | } |
2394 | ||
db24d33e | 2395 | ctx->is_active &= ~event_type; |
3cbaa590 PZ |
2396 | if (!(ctx->is_active & EVENT_ALL)) |
2397 | ctx->is_active = 0; | |
2398 | ||
63e30d3e PZ |
2399 | if (ctx->task) { |
2400 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
2401 | if (!ctx->is_active) | |
2402 | cpuctx->task_ctx = NULL; | |
2403 | } | |
facc4307 | 2404 | |
3cbaa590 PZ |
2405 | is_active ^= ctx->is_active; /* changed bits */ |
2406 | ||
2407 | if (is_active & EVENT_TIME) { | |
2408 | /* update (and stop) ctx time */ | |
2409 | update_context_time(ctx); | |
2410 | update_cgrp_time_from_cpuctx(cpuctx); | |
2411 | } | |
2412 | ||
2413 | if (!ctx->nr_active || !(is_active & EVENT_ALL)) | |
facc4307 | 2414 | return; |
5b0311e1 | 2415 | |
075e0b00 | 2416 | perf_pmu_disable(ctx->pmu); |
3cbaa590 | 2417 | if (is_active & EVENT_PINNED) { |
889ff015 FW |
2418 | list_for_each_entry(event, &ctx->pinned_groups, group_entry) |
2419 | group_sched_out(event, cpuctx, ctx); | |
9ed6060d | 2420 | } |
889ff015 | 2421 | |
3cbaa590 | 2422 | if (is_active & EVENT_FLEXIBLE) { |
889ff015 | 2423 | list_for_each_entry(event, &ctx->flexible_groups, group_entry) |
8c9ed8e1 | 2424 | group_sched_out(event, cpuctx, ctx); |
9ed6060d | 2425 | } |
1b9a644f | 2426 | perf_pmu_enable(ctx->pmu); |
235c7fc7 IM |
2427 | } |
2428 | ||
564c2b21 | 2429 | /* |
5a3126d4 PZ |
2430 | * Test whether two contexts are equivalent, i.e. whether they have both been |
2431 | * cloned from the same version of the same context. | |
2432 | * | |
2433 | * Equivalence is measured using a generation number in the context that is | |
2434 | * incremented on each modification to it; see unclone_ctx(), list_add_event() | |
2435 | * and list_del_event(). | |
564c2b21 | 2436 | */ |
cdd6c482 IM |
2437 | static int context_equiv(struct perf_event_context *ctx1, |
2438 | struct perf_event_context *ctx2) | |
564c2b21 | 2439 | { |
211de6eb PZ |
2440 | lockdep_assert_held(&ctx1->lock); |
2441 | lockdep_assert_held(&ctx2->lock); | |
2442 | ||
5a3126d4 PZ |
2443 | /* Pinning disables the swap optimization */ |
2444 | if (ctx1->pin_count || ctx2->pin_count) | |
2445 | return 0; | |
2446 | ||
2447 | /* If ctx1 is the parent of ctx2 */ | |
2448 | if (ctx1 == ctx2->parent_ctx && ctx1->generation == ctx2->parent_gen) | |
2449 | return 1; | |
2450 | ||
2451 | /* If ctx2 is the parent of ctx1 */ | |
2452 | if (ctx1->parent_ctx == ctx2 && ctx1->parent_gen == ctx2->generation) | |
2453 | return 1; | |
2454 | ||
2455 | /* | |
2456 | * If ctx1 and ctx2 have the same parent; we flatten the parent | |
2457 | * hierarchy, see perf_event_init_context(). | |
2458 | */ | |
2459 | if (ctx1->parent_ctx && ctx1->parent_ctx == ctx2->parent_ctx && | |
2460 | ctx1->parent_gen == ctx2->parent_gen) | |
2461 | return 1; | |
2462 | ||
2463 | /* Unmatched */ | |
2464 | return 0; | |
564c2b21 PM |
2465 | } |
2466 | ||
cdd6c482 IM |
2467 | static void __perf_event_sync_stat(struct perf_event *event, |
2468 | struct perf_event *next_event) | |
bfbd3381 PZ |
2469 | { |
2470 | u64 value; | |
2471 | ||
cdd6c482 | 2472 | if (!event->attr.inherit_stat) |
bfbd3381 PZ |
2473 | return; |
2474 | ||
2475 | /* | |
cdd6c482 | 2476 | * Update the event value, we cannot use perf_event_read() |
bfbd3381 PZ |
2477 | * because we're in the middle of a context switch and have IRQs |
2478 | * disabled, which upsets smp_call_function_single(), however | |
cdd6c482 | 2479 | * we know the event must be on the current CPU, therefore we |
bfbd3381 PZ |
2480 | * don't need to use it. |
2481 | */ | |
cdd6c482 IM |
2482 | switch (event->state) { |
2483 | case PERF_EVENT_STATE_ACTIVE: | |
3dbebf15 PZ |
2484 | event->pmu->read(event); |
2485 | /* fall-through */ | |
bfbd3381 | 2486 | |
cdd6c482 IM |
2487 | case PERF_EVENT_STATE_INACTIVE: |
2488 | update_event_times(event); | |
bfbd3381 PZ |
2489 | break; |
2490 | ||
2491 | default: | |
2492 | break; | |
2493 | } | |
2494 | ||
2495 | /* | |
cdd6c482 | 2496 | * In order to keep per-task stats reliable we need to flip the event |
bfbd3381 PZ |
2497 | * values when we flip the contexts. |
2498 | */ | |
e7850595 PZ |
2499 | value = local64_read(&next_event->count); |
2500 | value = local64_xchg(&event->count, value); | |
2501 | local64_set(&next_event->count, value); | |
bfbd3381 | 2502 | |
cdd6c482 IM |
2503 | swap(event->total_time_enabled, next_event->total_time_enabled); |
2504 | swap(event->total_time_running, next_event->total_time_running); | |
19d2e755 | 2505 | |
bfbd3381 | 2506 | /* |
19d2e755 | 2507 | * Since we swizzled the values, update the user visible data too. |
bfbd3381 | 2508 | */ |
cdd6c482 IM |
2509 | perf_event_update_userpage(event); |
2510 | perf_event_update_userpage(next_event); | |
bfbd3381 PZ |
2511 | } |
2512 | ||
cdd6c482 IM |
2513 | static void perf_event_sync_stat(struct perf_event_context *ctx, |
2514 | struct perf_event_context *next_ctx) | |
bfbd3381 | 2515 | { |
cdd6c482 | 2516 | struct perf_event *event, *next_event; |
bfbd3381 PZ |
2517 | |
2518 | if (!ctx->nr_stat) | |
2519 | return; | |
2520 | ||
02ffdbc8 PZ |
2521 | update_context_time(ctx); |
2522 | ||
cdd6c482 IM |
2523 | event = list_first_entry(&ctx->event_list, |
2524 | struct perf_event, event_entry); | |
bfbd3381 | 2525 | |
cdd6c482 IM |
2526 | next_event = list_first_entry(&next_ctx->event_list, |
2527 | struct perf_event, event_entry); | |
bfbd3381 | 2528 | |
cdd6c482 IM |
2529 | while (&event->event_entry != &ctx->event_list && |
2530 | &next_event->event_entry != &next_ctx->event_list) { | |
bfbd3381 | 2531 | |
cdd6c482 | 2532 | __perf_event_sync_stat(event, next_event); |
bfbd3381 | 2533 | |
cdd6c482 IM |
2534 | event = list_next_entry(event, event_entry); |
2535 | next_event = list_next_entry(next_event, event_entry); | |
bfbd3381 PZ |
2536 | } |
2537 | } | |
2538 | ||
fe4b04fa PZ |
2539 | static void perf_event_context_sched_out(struct task_struct *task, int ctxn, |
2540 | struct task_struct *next) | |
0793a61d | 2541 | { |
8dc85d54 | 2542 | struct perf_event_context *ctx = task->perf_event_ctxp[ctxn]; |
cdd6c482 | 2543 | struct perf_event_context *next_ctx; |
5a3126d4 | 2544 | struct perf_event_context *parent, *next_parent; |
108b02cf | 2545 | struct perf_cpu_context *cpuctx; |
c93f7669 | 2546 | int do_switch = 1; |
0793a61d | 2547 | |
108b02cf PZ |
2548 | if (likely(!ctx)) |
2549 | return; | |
10989fb2 | 2550 | |
108b02cf PZ |
2551 | cpuctx = __get_cpu_context(ctx); |
2552 | if (!cpuctx->task_ctx) | |
0793a61d TG |
2553 | return; |
2554 | ||
c93f7669 | 2555 | rcu_read_lock(); |
8dc85d54 | 2556 | next_ctx = next->perf_event_ctxp[ctxn]; |
5a3126d4 PZ |
2557 | if (!next_ctx) |
2558 | goto unlock; | |
2559 | ||
2560 | parent = rcu_dereference(ctx->parent_ctx); | |
2561 | next_parent = rcu_dereference(next_ctx->parent_ctx); | |
2562 | ||
2563 | /* If neither context have a parent context; they cannot be clones. */ | |
802c8a61 | 2564 | if (!parent && !next_parent) |
5a3126d4 PZ |
2565 | goto unlock; |
2566 | ||
2567 | if (next_parent == ctx || next_ctx == parent || next_parent == parent) { | |
c93f7669 PM |
2568 | /* |
2569 | * Looks like the two contexts are clones, so we might be | |
2570 | * able to optimize the context switch. We lock both | |
2571 | * contexts and check that they are clones under the | |
2572 | * lock (including re-checking that neither has been | |
2573 | * uncloned in the meantime). It doesn't matter which | |
2574 | * order we take the locks because no other cpu could | |
2575 | * be trying to lock both of these tasks. | |
2576 | */ | |
e625cce1 TG |
2577 | raw_spin_lock(&ctx->lock); |
2578 | raw_spin_lock_nested(&next_ctx->lock, SINGLE_DEPTH_NESTING); | |
c93f7669 | 2579 | if (context_equiv(ctx, next_ctx)) { |
63b6da39 PZ |
2580 | WRITE_ONCE(ctx->task, next); |
2581 | WRITE_ONCE(next_ctx->task, task); | |
5a158c3c YZ |
2582 | |
2583 | swap(ctx->task_ctx_data, next_ctx->task_ctx_data); | |
2584 | ||
63b6da39 PZ |
2585 | /* |
2586 | * RCU_INIT_POINTER here is safe because we've not | |
2587 | * modified the ctx and the above modification of | |
2588 | * ctx->task and ctx->task_ctx_data are immaterial | |
2589 | * since those values are always verified under | |
2590 | * ctx->lock which we're now holding. | |
2591 | */ | |
2592 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], next_ctx); | |
2593 | RCU_INIT_POINTER(next->perf_event_ctxp[ctxn], ctx); | |
2594 | ||
c93f7669 | 2595 | do_switch = 0; |
bfbd3381 | 2596 | |
cdd6c482 | 2597 | perf_event_sync_stat(ctx, next_ctx); |
c93f7669 | 2598 | } |
e625cce1 TG |
2599 | raw_spin_unlock(&next_ctx->lock); |
2600 | raw_spin_unlock(&ctx->lock); | |
564c2b21 | 2601 | } |
5a3126d4 | 2602 | unlock: |
c93f7669 | 2603 | rcu_read_unlock(); |
564c2b21 | 2604 | |
c93f7669 | 2605 | if (do_switch) { |
facc4307 | 2606 | raw_spin_lock(&ctx->lock); |
8833d0e2 | 2607 | task_ctx_sched_out(cpuctx, ctx); |
facc4307 | 2608 | raw_spin_unlock(&ctx->lock); |
c93f7669 | 2609 | } |
0793a61d TG |
2610 | } |
2611 | ||
ba532500 YZ |
2612 | void perf_sched_cb_dec(struct pmu *pmu) |
2613 | { | |
2614 | this_cpu_dec(perf_sched_cb_usages); | |
2615 | } | |
2616 | ||
2617 | void perf_sched_cb_inc(struct pmu *pmu) | |
2618 | { | |
2619 | this_cpu_inc(perf_sched_cb_usages); | |
2620 | } | |
2621 | ||
2622 | /* | |
2623 | * This function provides the context switch callback to the lower code | |
2624 | * layer. It is invoked ONLY when the context switch callback is enabled. | |
2625 | */ | |
2626 | static void perf_pmu_sched_task(struct task_struct *prev, | |
2627 | struct task_struct *next, | |
2628 | bool sched_in) | |
2629 | { | |
2630 | struct perf_cpu_context *cpuctx; | |
2631 | struct pmu *pmu; | |
2632 | unsigned long flags; | |
2633 | ||
2634 | if (prev == next) | |
2635 | return; | |
2636 | ||
2637 | local_irq_save(flags); | |
2638 | ||
2639 | rcu_read_lock(); | |
2640 | ||
2641 | list_for_each_entry_rcu(pmu, &pmus, entry) { | |
2642 | if (pmu->sched_task) { | |
2643 | cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); | |
2644 | ||
2645 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); | |
2646 | ||
2647 | perf_pmu_disable(pmu); | |
2648 | ||
2649 | pmu->sched_task(cpuctx->task_ctx, sched_in); | |
2650 | ||
2651 | perf_pmu_enable(pmu); | |
2652 | ||
2653 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
2654 | } | |
2655 | } | |
2656 | ||
2657 | rcu_read_unlock(); | |
2658 | ||
2659 | local_irq_restore(flags); | |
2660 | } | |
2661 | ||
45ac1403 AH |
2662 | static void perf_event_switch(struct task_struct *task, |
2663 | struct task_struct *next_prev, bool sched_in); | |
2664 | ||
8dc85d54 PZ |
2665 | #define for_each_task_context_nr(ctxn) \ |
2666 | for ((ctxn) = 0; (ctxn) < perf_nr_task_contexts; (ctxn)++) | |
2667 | ||
2668 | /* | |
2669 | * Called from scheduler to remove the events of the current task, | |
2670 | * with interrupts disabled. | |
2671 | * | |
2672 | * We stop each event and update the event value in event->count. | |
2673 | * | |
2674 | * This does not protect us against NMI, but disable() | |
2675 | * sets the disabled bit in the control field of event _before_ | |
2676 | * accessing the event control register. If a NMI hits, then it will | |
2677 | * not restart the event. | |
2678 | */ | |
ab0cce56 JO |
2679 | void __perf_event_task_sched_out(struct task_struct *task, |
2680 | struct task_struct *next) | |
8dc85d54 PZ |
2681 | { |
2682 | int ctxn; | |
2683 | ||
ba532500 YZ |
2684 | if (__this_cpu_read(perf_sched_cb_usages)) |
2685 | perf_pmu_sched_task(task, next, false); | |
2686 | ||
45ac1403 AH |
2687 | if (atomic_read(&nr_switch_events)) |
2688 | perf_event_switch(task, next, false); | |
2689 | ||
8dc85d54 PZ |
2690 | for_each_task_context_nr(ctxn) |
2691 | perf_event_context_sched_out(task, ctxn, next); | |
e5d1367f SE |
2692 | |
2693 | /* | |
2694 | * if cgroup events exist on this CPU, then we need | |
2695 | * to check if we have to switch out PMU state. | |
2696 | * cgroup event are system-wide mode only | |
2697 | */ | |
4a32fea9 | 2698 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) |
a8d757ef | 2699 | perf_cgroup_sched_out(task, next); |
8dc85d54 PZ |
2700 | } |
2701 | ||
5b0311e1 FW |
2702 | /* |
2703 | * Called with IRQs disabled | |
2704 | */ | |
2705 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, | |
2706 | enum event_type_t event_type) | |
2707 | { | |
2708 | ctx_sched_out(&cpuctx->ctx, cpuctx, event_type); | |
04289bb9 IM |
2709 | } |
2710 | ||
235c7fc7 | 2711 | static void |
5b0311e1 | 2712 | ctx_pinned_sched_in(struct perf_event_context *ctx, |
6e37738a | 2713 | struct perf_cpu_context *cpuctx) |
0793a61d | 2714 | { |
cdd6c482 | 2715 | struct perf_event *event; |
0793a61d | 2716 | |
889ff015 FW |
2717 | list_for_each_entry(event, &ctx->pinned_groups, group_entry) { |
2718 | if (event->state <= PERF_EVENT_STATE_OFF) | |
3b6f9e5c | 2719 | continue; |
5632ab12 | 2720 | if (!event_filter_match(event)) |
3b6f9e5c PM |
2721 | continue; |
2722 | ||
e5d1367f SE |
2723 | /* may need to reset tstamp_enabled */ |
2724 | if (is_cgroup_event(event)) | |
2725 | perf_cgroup_mark_enabled(event, ctx); | |
2726 | ||
8c9ed8e1 | 2727 | if (group_can_go_on(event, cpuctx, 1)) |
6e37738a | 2728 | group_sched_in(event, cpuctx, ctx); |
3b6f9e5c PM |
2729 | |
2730 | /* | |
2731 | * If this pinned group hasn't been scheduled, | |
2732 | * put it in error state. | |
2733 | */ | |
cdd6c482 IM |
2734 | if (event->state == PERF_EVENT_STATE_INACTIVE) { |
2735 | update_group_times(event); | |
2736 | event->state = PERF_EVENT_STATE_ERROR; | |
53cfbf59 | 2737 | } |
3b6f9e5c | 2738 | } |
5b0311e1 FW |
2739 | } |
2740 | ||
2741 | static void | |
2742 | ctx_flexible_sched_in(struct perf_event_context *ctx, | |
6e37738a | 2743 | struct perf_cpu_context *cpuctx) |
5b0311e1 FW |
2744 | { |
2745 | struct perf_event *event; | |
2746 | int can_add_hw = 1; | |
3b6f9e5c | 2747 | |
889ff015 FW |
2748 | list_for_each_entry(event, &ctx->flexible_groups, group_entry) { |
2749 | /* Ignore events in OFF or ERROR state */ | |
2750 | if (event->state <= PERF_EVENT_STATE_OFF) | |
3b6f9e5c | 2751 | continue; |
04289bb9 IM |
2752 | /* |
2753 | * Listen to the 'cpu' scheduling filter constraint | |
cdd6c482 | 2754 | * of events: |
04289bb9 | 2755 | */ |
5632ab12 | 2756 | if (!event_filter_match(event)) |
0793a61d TG |
2757 | continue; |
2758 | ||
e5d1367f SE |
2759 | /* may need to reset tstamp_enabled */ |
2760 | if (is_cgroup_event(event)) | |
2761 | perf_cgroup_mark_enabled(event, ctx); | |
2762 | ||
9ed6060d | 2763 | if (group_can_go_on(event, cpuctx, can_add_hw)) { |
6e37738a | 2764 | if (group_sched_in(event, cpuctx, ctx)) |
dd0e6ba2 | 2765 | can_add_hw = 0; |
9ed6060d | 2766 | } |
0793a61d | 2767 | } |
5b0311e1 FW |
2768 | } |
2769 | ||
2770 | static void | |
2771 | ctx_sched_in(struct perf_event_context *ctx, | |
2772 | struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
2773 | enum event_type_t event_type, |
2774 | struct task_struct *task) | |
5b0311e1 | 2775 | { |
db24d33e | 2776 | int is_active = ctx->is_active; |
c994d613 PZ |
2777 | u64 now; |
2778 | ||
2779 | lockdep_assert_held(&ctx->lock); | |
e5d1367f | 2780 | |
5b0311e1 | 2781 | if (likely(!ctx->nr_events)) |
facc4307 | 2782 | return; |
5b0311e1 | 2783 | |
3cbaa590 | 2784 | ctx->is_active |= (event_type | EVENT_TIME); |
63e30d3e PZ |
2785 | if (ctx->task) { |
2786 | if (!is_active) | |
2787 | cpuctx->task_ctx = ctx; | |
2788 | else | |
2789 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
2790 | } | |
2791 | ||
3cbaa590 PZ |
2792 | is_active ^= ctx->is_active; /* changed bits */ |
2793 | ||
2794 | if (is_active & EVENT_TIME) { | |
2795 | /* start ctx time */ | |
2796 | now = perf_clock(); | |
2797 | ctx->timestamp = now; | |
2798 | perf_cgroup_set_timestamp(task, ctx); | |
2799 | } | |
2800 | ||
5b0311e1 FW |
2801 | /* |
2802 | * First go through the list and put on any pinned groups | |
2803 | * in order to give them the best chance of going on. | |
2804 | */ | |
3cbaa590 | 2805 | if (is_active & EVENT_PINNED) |
6e37738a | 2806 | ctx_pinned_sched_in(ctx, cpuctx); |
5b0311e1 FW |
2807 | |
2808 | /* Then walk through the lower prio flexible groups */ | |
3cbaa590 | 2809 | if (is_active & EVENT_FLEXIBLE) |
6e37738a | 2810 | ctx_flexible_sched_in(ctx, cpuctx); |
235c7fc7 IM |
2811 | } |
2812 | ||
329c0e01 | 2813 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, |
e5d1367f SE |
2814 | enum event_type_t event_type, |
2815 | struct task_struct *task) | |
329c0e01 FW |
2816 | { |
2817 | struct perf_event_context *ctx = &cpuctx->ctx; | |
2818 | ||
e5d1367f | 2819 | ctx_sched_in(ctx, cpuctx, event_type, task); |
329c0e01 FW |
2820 | } |
2821 | ||
e5d1367f SE |
2822 | static void perf_event_context_sched_in(struct perf_event_context *ctx, |
2823 | struct task_struct *task) | |
235c7fc7 | 2824 | { |
108b02cf | 2825 | struct perf_cpu_context *cpuctx; |
235c7fc7 | 2826 | |
108b02cf | 2827 | cpuctx = __get_cpu_context(ctx); |
329c0e01 FW |
2828 | if (cpuctx->task_ctx == ctx) |
2829 | return; | |
2830 | ||
facc4307 | 2831 | perf_ctx_lock(cpuctx, ctx); |
1b9a644f | 2832 | perf_pmu_disable(ctx->pmu); |
329c0e01 FW |
2833 | /* |
2834 | * We want to keep the following priority order: | |
2835 | * cpu pinned (that don't need to move), task pinned, | |
2836 | * cpu flexible, task flexible. | |
2837 | */ | |
2838 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
63e30d3e | 2839 | perf_event_sched_in(cpuctx, ctx, task); |
facc4307 PZ |
2840 | perf_pmu_enable(ctx->pmu); |
2841 | perf_ctx_unlock(cpuctx, ctx); | |
235c7fc7 IM |
2842 | } |
2843 | ||
8dc85d54 PZ |
2844 | /* |
2845 | * Called from scheduler to add the events of the current task | |
2846 | * with interrupts disabled. | |
2847 | * | |
2848 | * We restore the event value and then enable it. | |
2849 | * | |
2850 | * This does not protect us against NMI, but enable() | |
2851 | * sets the enabled bit in the control field of event _before_ | |
2852 | * accessing the event control register. If a NMI hits, then it will | |
2853 | * keep the event running. | |
2854 | */ | |
ab0cce56 JO |
2855 | void __perf_event_task_sched_in(struct task_struct *prev, |
2856 | struct task_struct *task) | |
8dc85d54 PZ |
2857 | { |
2858 | struct perf_event_context *ctx; | |
2859 | int ctxn; | |
2860 | ||
7e41d177 PZ |
2861 | /* |
2862 | * If cgroup events exist on this CPU, then we need to check if we have | |
2863 | * to switch in PMU state; cgroup event are system-wide mode only. | |
2864 | * | |
2865 | * Since cgroup events are CPU events, we must schedule these in before | |
2866 | * we schedule in the task events. | |
2867 | */ | |
2868 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) | |
2869 | perf_cgroup_sched_in(prev, task); | |
2870 | ||
8dc85d54 PZ |
2871 | for_each_task_context_nr(ctxn) { |
2872 | ctx = task->perf_event_ctxp[ctxn]; | |
2873 | if (likely(!ctx)) | |
2874 | continue; | |
2875 | ||
e5d1367f | 2876 | perf_event_context_sched_in(ctx, task); |
8dc85d54 | 2877 | } |
d010b332 | 2878 | |
45ac1403 AH |
2879 | if (atomic_read(&nr_switch_events)) |
2880 | perf_event_switch(task, prev, true); | |
2881 | ||
ba532500 YZ |
2882 | if (__this_cpu_read(perf_sched_cb_usages)) |
2883 | perf_pmu_sched_task(prev, task, true); | |
235c7fc7 IM |
2884 | } |
2885 | ||
abd50713 PZ |
2886 | static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count) |
2887 | { | |
2888 | u64 frequency = event->attr.sample_freq; | |
2889 | u64 sec = NSEC_PER_SEC; | |
2890 | u64 divisor, dividend; | |
2891 | ||
2892 | int count_fls, nsec_fls, frequency_fls, sec_fls; | |
2893 | ||
2894 | count_fls = fls64(count); | |
2895 | nsec_fls = fls64(nsec); | |
2896 | frequency_fls = fls64(frequency); | |
2897 | sec_fls = 30; | |
2898 | ||
2899 | /* | |
2900 | * We got @count in @nsec, with a target of sample_freq HZ | |
2901 | * the target period becomes: | |
2902 | * | |
2903 | * @count * 10^9 | |
2904 | * period = ------------------- | |
2905 | * @nsec * sample_freq | |
2906 | * | |
2907 | */ | |
2908 | ||
2909 | /* | |
2910 | * Reduce accuracy by one bit such that @a and @b converge | |
2911 | * to a similar magnitude. | |
2912 | */ | |
fe4b04fa | 2913 | #define REDUCE_FLS(a, b) \ |
abd50713 PZ |
2914 | do { \ |
2915 | if (a##_fls > b##_fls) { \ | |
2916 | a >>= 1; \ | |
2917 | a##_fls--; \ | |
2918 | } else { \ | |
2919 | b >>= 1; \ | |
2920 | b##_fls--; \ | |
2921 | } \ | |
2922 | } while (0) | |
2923 | ||
2924 | /* | |
2925 | * Reduce accuracy until either term fits in a u64, then proceed with | |
2926 | * the other, so that finally we can do a u64/u64 division. | |
2927 | */ | |
2928 | while (count_fls + sec_fls > 64 && nsec_fls + frequency_fls > 64) { | |
2929 | REDUCE_FLS(nsec, frequency); | |
2930 | REDUCE_FLS(sec, count); | |
2931 | } | |
2932 | ||
2933 | if (count_fls + sec_fls > 64) { | |
2934 | divisor = nsec * frequency; | |
2935 | ||
2936 | while (count_fls + sec_fls > 64) { | |
2937 | REDUCE_FLS(count, sec); | |
2938 | divisor >>= 1; | |
2939 | } | |
2940 | ||
2941 | dividend = count * sec; | |
2942 | } else { | |
2943 | dividend = count * sec; | |
2944 | ||
2945 | while (nsec_fls + frequency_fls > 64) { | |
2946 | REDUCE_FLS(nsec, frequency); | |
2947 | dividend >>= 1; | |
2948 | } | |
2949 | ||
2950 | divisor = nsec * frequency; | |
2951 | } | |
2952 | ||
f6ab91ad PZ |
2953 | if (!divisor) |
2954 | return dividend; | |
2955 | ||
abd50713 PZ |
2956 | return div64_u64(dividend, divisor); |
2957 | } | |
2958 | ||
e050e3f0 SE |
2959 | static DEFINE_PER_CPU(int, perf_throttled_count); |
2960 | static DEFINE_PER_CPU(u64, perf_throttled_seq); | |
2961 | ||
f39d47ff | 2962 | static void perf_adjust_period(struct perf_event *event, u64 nsec, u64 count, bool disable) |
bd2b5b12 | 2963 | { |
cdd6c482 | 2964 | struct hw_perf_event *hwc = &event->hw; |
f6ab91ad | 2965 | s64 period, sample_period; |
bd2b5b12 PZ |
2966 | s64 delta; |
2967 | ||
abd50713 | 2968 | period = perf_calculate_period(event, nsec, count); |
bd2b5b12 PZ |
2969 | |
2970 | delta = (s64)(period - hwc->sample_period); | |
2971 | delta = (delta + 7) / 8; /* low pass filter */ | |
2972 | ||
2973 | sample_period = hwc->sample_period + delta; | |
2974 | ||
2975 | if (!sample_period) | |
2976 | sample_period = 1; | |
2977 | ||
bd2b5b12 | 2978 | hwc->sample_period = sample_period; |
abd50713 | 2979 | |
e7850595 | 2980 | if (local64_read(&hwc->period_left) > 8*sample_period) { |
f39d47ff SE |
2981 | if (disable) |
2982 | event->pmu->stop(event, PERF_EF_UPDATE); | |
2983 | ||
e7850595 | 2984 | local64_set(&hwc->period_left, 0); |
f39d47ff SE |
2985 | |
2986 | if (disable) | |
2987 | event->pmu->start(event, PERF_EF_RELOAD); | |
abd50713 | 2988 | } |
bd2b5b12 PZ |
2989 | } |
2990 | ||
e050e3f0 SE |
2991 | /* |
2992 | * combine freq adjustment with unthrottling to avoid two passes over the | |
2993 | * events. At the same time, make sure, having freq events does not change | |
2994 | * the rate of unthrottling as that would introduce bias. | |
2995 | */ | |
2996 | static void perf_adjust_freq_unthr_context(struct perf_event_context *ctx, | |
2997 | int needs_unthr) | |
60db5e09 | 2998 | { |
cdd6c482 IM |
2999 | struct perf_event *event; |
3000 | struct hw_perf_event *hwc; | |
e050e3f0 | 3001 | u64 now, period = TICK_NSEC; |
abd50713 | 3002 | s64 delta; |
60db5e09 | 3003 | |
e050e3f0 SE |
3004 | /* |
3005 | * only need to iterate over all events iff: | |
3006 | * - context have events in frequency mode (needs freq adjust) | |
3007 | * - there are events to unthrottle on this cpu | |
3008 | */ | |
3009 | if (!(ctx->nr_freq || needs_unthr)) | |
0f5a2601 PZ |
3010 | return; |
3011 | ||
e050e3f0 | 3012 | raw_spin_lock(&ctx->lock); |
f39d47ff | 3013 | perf_pmu_disable(ctx->pmu); |
e050e3f0 | 3014 | |
03541f8b | 3015 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { |
cdd6c482 | 3016 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
60db5e09 PZ |
3017 | continue; |
3018 | ||
5632ab12 | 3019 | if (!event_filter_match(event)) |
5d27c23d PZ |
3020 | continue; |
3021 | ||
44377277 AS |
3022 | perf_pmu_disable(event->pmu); |
3023 | ||
cdd6c482 | 3024 | hwc = &event->hw; |
6a24ed6c | 3025 | |
ae23bff1 | 3026 | if (hwc->interrupts == MAX_INTERRUPTS) { |
e050e3f0 | 3027 | hwc->interrupts = 0; |
cdd6c482 | 3028 | perf_log_throttle(event, 1); |
a4eaf7f1 | 3029 | event->pmu->start(event, 0); |
a78ac325 PZ |
3030 | } |
3031 | ||
cdd6c482 | 3032 | if (!event->attr.freq || !event->attr.sample_freq) |
44377277 | 3033 | goto next; |
60db5e09 | 3034 | |
e050e3f0 SE |
3035 | /* |
3036 | * stop the event and update event->count | |
3037 | */ | |
3038 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3039 | ||
e7850595 | 3040 | now = local64_read(&event->count); |
abd50713 PZ |
3041 | delta = now - hwc->freq_count_stamp; |
3042 | hwc->freq_count_stamp = now; | |
60db5e09 | 3043 | |
e050e3f0 SE |
3044 | /* |
3045 | * restart the event | |
3046 | * reload only if value has changed | |
f39d47ff SE |
3047 | * we have stopped the event so tell that |
3048 | * to perf_adjust_period() to avoid stopping it | |
3049 | * twice. | |
e050e3f0 | 3050 | */ |
abd50713 | 3051 | if (delta > 0) |
f39d47ff | 3052 | perf_adjust_period(event, period, delta, false); |
e050e3f0 SE |
3053 | |
3054 | event->pmu->start(event, delta > 0 ? PERF_EF_RELOAD : 0); | |
44377277 AS |
3055 | next: |
3056 | perf_pmu_enable(event->pmu); | |
60db5e09 | 3057 | } |
e050e3f0 | 3058 | |
f39d47ff | 3059 | perf_pmu_enable(ctx->pmu); |
e050e3f0 | 3060 | raw_spin_unlock(&ctx->lock); |
60db5e09 PZ |
3061 | } |
3062 | ||
235c7fc7 | 3063 | /* |
cdd6c482 | 3064 | * Round-robin a context's events: |
235c7fc7 | 3065 | */ |
cdd6c482 | 3066 | static void rotate_ctx(struct perf_event_context *ctx) |
0793a61d | 3067 | { |
dddd3379 TG |
3068 | /* |
3069 | * Rotate the first entry last of non-pinned groups. Rotation might be | |
3070 | * disabled by the inheritance code. | |
3071 | */ | |
3072 | if (!ctx->rotate_disable) | |
3073 | list_rotate_left(&ctx->flexible_groups); | |
235c7fc7 IM |
3074 | } |
3075 | ||
9e630205 | 3076 | static int perf_rotate_context(struct perf_cpu_context *cpuctx) |
235c7fc7 | 3077 | { |
8dc85d54 | 3078 | struct perf_event_context *ctx = NULL; |
2fde4f94 | 3079 | int rotate = 0; |
7fc23a53 | 3080 | |
b5ab4cd5 | 3081 | if (cpuctx->ctx.nr_events) { |
b5ab4cd5 PZ |
3082 | if (cpuctx->ctx.nr_events != cpuctx->ctx.nr_active) |
3083 | rotate = 1; | |
3084 | } | |
235c7fc7 | 3085 | |
8dc85d54 | 3086 | ctx = cpuctx->task_ctx; |
b5ab4cd5 | 3087 | if (ctx && ctx->nr_events) { |
b5ab4cd5 PZ |
3088 | if (ctx->nr_events != ctx->nr_active) |
3089 | rotate = 1; | |
3090 | } | |
9717e6cd | 3091 | |
e050e3f0 | 3092 | if (!rotate) |
0f5a2601 PZ |
3093 | goto done; |
3094 | ||
facc4307 | 3095 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
1b9a644f | 3096 | perf_pmu_disable(cpuctx->ctx.pmu); |
60db5e09 | 3097 | |
e050e3f0 SE |
3098 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); |
3099 | if (ctx) | |
3100 | ctx_sched_out(ctx, cpuctx, EVENT_FLEXIBLE); | |
0793a61d | 3101 | |
e050e3f0 SE |
3102 | rotate_ctx(&cpuctx->ctx); |
3103 | if (ctx) | |
3104 | rotate_ctx(ctx); | |
235c7fc7 | 3105 | |
e050e3f0 | 3106 | perf_event_sched_in(cpuctx, ctx, current); |
235c7fc7 | 3107 | |
0f5a2601 PZ |
3108 | perf_pmu_enable(cpuctx->ctx.pmu); |
3109 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
b5ab4cd5 | 3110 | done: |
9e630205 SE |
3111 | |
3112 | return rotate; | |
e9d2b064 PZ |
3113 | } |
3114 | ||
3115 | void perf_event_task_tick(void) | |
3116 | { | |
2fde4f94 MR |
3117 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
3118 | struct perf_event_context *ctx, *tmp; | |
e050e3f0 | 3119 | int throttled; |
b5ab4cd5 | 3120 | |
e9d2b064 PZ |
3121 | WARN_ON(!irqs_disabled()); |
3122 | ||
e050e3f0 SE |
3123 | __this_cpu_inc(perf_throttled_seq); |
3124 | throttled = __this_cpu_xchg(perf_throttled_count, 0); | |
555e0c1e | 3125 | tick_dep_clear_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
e050e3f0 | 3126 | |
2fde4f94 | 3127 | list_for_each_entry_safe(ctx, tmp, head, active_ctx_list) |
e050e3f0 | 3128 | perf_adjust_freq_unthr_context(ctx, throttled); |
0793a61d TG |
3129 | } |
3130 | ||
889ff015 FW |
3131 | static int event_enable_on_exec(struct perf_event *event, |
3132 | struct perf_event_context *ctx) | |
3133 | { | |
3134 | if (!event->attr.enable_on_exec) | |
3135 | return 0; | |
3136 | ||
3137 | event->attr.enable_on_exec = 0; | |
3138 | if (event->state >= PERF_EVENT_STATE_INACTIVE) | |
3139 | return 0; | |
3140 | ||
1d9b482e | 3141 | __perf_event_mark_enabled(event); |
889ff015 FW |
3142 | |
3143 | return 1; | |
3144 | } | |
3145 | ||
57e7986e | 3146 | /* |
cdd6c482 | 3147 | * Enable all of a task's events that have been marked enable-on-exec. |
57e7986e PM |
3148 | * This expects task == current. |
3149 | */ | |
c1274499 | 3150 | static void perf_event_enable_on_exec(int ctxn) |
57e7986e | 3151 | { |
c1274499 | 3152 | struct perf_event_context *ctx, *clone_ctx = NULL; |
3e349507 | 3153 | struct perf_cpu_context *cpuctx; |
cdd6c482 | 3154 | struct perf_event *event; |
57e7986e PM |
3155 | unsigned long flags; |
3156 | int enabled = 0; | |
3157 | ||
3158 | local_irq_save(flags); | |
c1274499 | 3159 | ctx = current->perf_event_ctxp[ctxn]; |
cdd6c482 | 3160 | if (!ctx || !ctx->nr_events) |
57e7986e PM |
3161 | goto out; |
3162 | ||
3e349507 PZ |
3163 | cpuctx = __get_cpu_context(ctx); |
3164 | perf_ctx_lock(cpuctx, ctx); | |
7fce2509 | 3165 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
3e349507 PZ |
3166 | list_for_each_entry(event, &ctx->event_list, event_entry) |
3167 | enabled |= event_enable_on_exec(event, ctx); | |
57e7986e PM |
3168 | |
3169 | /* | |
3e349507 | 3170 | * Unclone and reschedule this context if we enabled any event. |
57e7986e | 3171 | */ |
3e349507 | 3172 | if (enabled) { |
211de6eb | 3173 | clone_ctx = unclone_ctx(ctx); |
3e349507 PZ |
3174 | ctx_resched(cpuctx, ctx); |
3175 | } | |
3176 | perf_ctx_unlock(cpuctx, ctx); | |
57e7986e | 3177 | |
9ed6060d | 3178 | out: |
57e7986e | 3179 | local_irq_restore(flags); |
211de6eb PZ |
3180 | |
3181 | if (clone_ctx) | |
3182 | put_ctx(clone_ctx); | |
57e7986e PM |
3183 | } |
3184 | ||
e041e328 PZ |
3185 | void perf_event_exec(void) |
3186 | { | |
e041e328 PZ |
3187 | int ctxn; |
3188 | ||
3189 | rcu_read_lock(); | |
c1274499 PZ |
3190 | for_each_task_context_nr(ctxn) |
3191 | perf_event_enable_on_exec(ctxn); | |
e041e328 PZ |
3192 | rcu_read_unlock(); |
3193 | } | |
3194 | ||
0492d4c5 PZ |
3195 | struct perf_read_data { |
3196 | struct perf_event *event; | |
3197 | bool group; | |
7d88962e | 3198 | int ret; |
0492d4c5 PZ |
3199 | }; |
3200 | ||
0793a61d | 3201 | /* |
cdd6c482 | 3202 | * Cross CPU call to read the hardware event |
0793a61d | 3203 | */ |
cdd6c482 | 3204 | static void __perf_event_read(void *info) |
0793a61d | 3205 | { |
0492d4c5 PZ |
3206 | struct perf_read_data *data = info; |
3207 | struct perf_event *sub, *event = data->event; | |
cdd6c482 | 3208 | struct perf_event_context *ctx = event->ctx; |
108b02cf | 3209 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
4a00c16e | 3210 | struct pmu *pmu = event->pmu; |
621a01ea | 3211 | |
e1ac3614 PM |
3212 | /* |
3213 | * If this is a task context, we need to check whether it is | |
3214 | * the current task context of this cpu. If not it has been | |
3215 | * scheduled out before the smp call arrived. In that case | |
cdd6c482 IM |
3216 | * event->count would have been updated to a recent sample |
3217 | * when the event was scheduled out. | |
e1ac3614 PM |
3218 | */ |
3219 | if (ctx->task && cpuctx->task_ctx != ctx) | |
3220 | return; | |
3221 | ||
e625cce1 | 3222 | raw_spin_lock(&ctx->lock); |
e5d1367f | 3223 | if (ctx->is_active) { |
542e72fc | 3224 | update_context_time(ctx); |
e5d1367f SE |
3225 | update_cgrp_time_from_event(event); |
3226 | } | |
0492d4c5 | 3227 | |
cdd6c482 | 3228 | update_event_times(event); |
4a00c16e SB |
3229 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
3230 | goto unlock; | |
0492d4c5 | 3231 | |
4a00c16e SB |
3232 | if (!data->group) { |
3233 | pmu->read(event); | |
3234 | data->ret = 0; | |
0492d4c5 | 3235 | goto unlock; |
4a00c16e SB |
3236 | } |
3237 | ||
3238 | pmu->start_txn(pmu, PERF_PMU_TXN_READ); | |
3239 | ||
3240 | pmu->read(event); | |
0492d4c5 PZ |
3241 | |
3242 | list_for_each_entry(sub, &event->sibling_list, group_entry) { | |
3243 | update_event_times(sub); | |
4a00c16e SB |
3244 | if (sub->state == PERF_EVENT_STATE_ACTIVE) { |
3245 | /* | |
3246 | * Use sibling's PMU rather than @event's since | |
3247 | * sibling could be on different (eg: software) PMU. | |
3248 | */ | |
0492d4c5 | 3249 | sub->pmu->read(sub); |
4a00c16e | 3250 | } |
0492d4c5 | 3251 | } |
4a00c16e SB |
3252 | |
3253 | data->ret = pmu->commit_txn(pmu); | |
0492d4c5 PZ |
3254 | |
3255 | unlock: | |
e625cce1 | 3256 | raw_spin_unlock(&ctx->lock); |
0793a61d TG |
3257 | } |
3258 | ||
b5e58793 PZ |
3259 | static inline u64 perf_event_count(struct perf_event *event) |
3260 | { | |
eacd3ecc MF |
3261 | if (event->pmu->count) |
3262 | return event->pmu->count(event); | |
3263 | ||
3264 | return __perf_event_count(event); | |
b5e58793 PZ |
3265 | } |
3266 | ||
ffe8690c KX |
3267 | /* |
3268 | * NMI-safe method to read a local event, that is an event that | |
3269 | * is: | |
3270 | * - either for the current task, or for this CPU | |
3271 | * - does not have inherit set, for inherited task events | |
3272 | * will not be local and we cannot read them atomically | |
3273 | * - must not have a pmu::count method | |
3274 | */ | |
3275 | u64 perf_event_read_local(struct perf_event *event) | |
3276 | { | |
3277 | unsigned long flags; | |
3278 | u64 val; | |
3279 | ||
3280 | /* | |
3281 | * Disabling interrupts avoids all counter scheduling (context | |
3282 | * switches, timer based rotation and IPIs). | |
3283 | */ | |
3284 | local_irq_save(flags); | |
3285 | ||
3286 | /* If this is a per-task event, it must be for current */ | |
3287 | WARN_ON_ONCE((event->attach_state & PERF_ATTACH_TASK) && | |
3288 | event->hw.target != current); | |
3289 | ||
3290 | /* If this is a per-CPU event, it must be for this CPU */ | |
3291 | WARN_ON_ONCE(!(event->attach_state & PERF_ATTACH_TASK) && | |
3292 | event->cpu != smp_processor_id()); | |
3293 | ||
3294 | /* | |
3295 | * It must not be an event with inherit set, we cannot read | |
3296 | * all child counters from atomic context. | |
3297 | */ | |
3298 | WARN_ON_ONCE(event->attr.inherit); | |
3299 | ||
3300 | /* | |
3301 | * It must not have a pmu::count method, those are not | |
3302 | * NMI safe. | |
3303 | */ | |
3304 | WARN_ON_ONCE(event->pmu->count); | |
3305 | ||
3306 | /* | |
3307 | * If the event is currently on this CPU, its either a per-task event, | |
3308 | * or local to this CPU. Furthermore it means its ACTIVE (otherwise | |
3309 | * oncpu == -1). | |
3310 | */ | |
3311 | if (event->oncpu == smp_processor_id()) | |
3312 | event->pmu->read(event); | |
3313 | ||
3314 | val = local64_read(&event->count); | |
3315 | local_irq_restore(flags); | |
3316 | ||
3317 | return val; | |
3318 | } | |
3319 | ||
7d88962e | 3320 | static int perf_event_read(struct perf_event *event, bool group) |
0793a61d | 3321 | { |
7d88962e SB |
3322 | int ret = 0; |
3323 | ||
0793a61d | 3324 | /* |
cdd6c482 IM |
3325 | * If event is enabled and currently active on a CPU, update the |
3326 | * value in the event structure: | |
0793a61d | 3327 | */ |
cdd6c482 | 3328 | if (event->state == PERF_EVENT_STATE_ACTIVE) { |
0492d4c5 PZ |
3329 | struct perf_read_data data = { |
3330 | .event = event, | |
3331 | .group = group, | |
7d88962e | 3332 | .ret = 0, |
0492d4c5 | 3333 | }; |
cdd6c482 | 3334 | smp_call_function_single(event->oncpu, |
0492d4c5 | 3335 | __perf_event_read, &data, 1); |
7d88962e | 3336 | ret = data.ret; |
cdd6c482 | 3337 | } else if (event->state == PERF_EVENT_STATE_INACTIVE) { |
2b8988c9 PZ |
3338 | struct perf_event_context *ctx = event->ctx; |
3339 | unsigned long flags; | |
3340 | ||
e625cce1 | 3341 | raw_spin_lock_irqsave(&ctx->lock, flags); |
c530ccd9 SE |
3342 | /* |
3343 | * may read while context is not active | |
3344 | * (e.g., thread is blocked), in that case | |
3345 | * we cannot update context time | |
3346 | */ | |
e5d1367f | 3347 | if (ctx->is_active) { |
c530ccd9 | 3348 | update_context_time(ctx); |
e5d1367f SE |
3349 | update_cgrp_time_from_event(event); |
3350 | } | |
0492d4c5 PZ |
3351 | if (group) |
3352 | update_group_times(event); | |
3353 | else | |
3354 | update_event_times(event); | |
e625cce1 | 3355 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
0793a61d | 3356 | } |
7d88962e SB |
3357 | |
3358 | return ret; | |
0793a61d TG |
3359 | } |
3360 | ||
a63eaf34 | 3361 | /* |
cdd6c482 | 3362 | * Initialize the perf_event context in a task_struct: |
a63eaf34 | 3363 | */ |
eb184479 | 3364 | static void __perf_event_init_context(struct perf_event_context *ctx) |
a63eaf34 | 3365 | { |
e625cce1 | 3366 | raw_spin_lock_init(&ctx->lock); |
a63eaf34 | 3367 | mutex_init(&ctx->mutex); |
2fde4f94 | 3368 | INIT_LIST_HEAD(&ctx->active_ctx_list); |
889ff015 FW |
3369 | INIT_LIST_HEAD(&ctx->pinned_groups); |
3370 | INIT_LIST_HEAD(&ctx->flexible_groups); | |
a63eaf34 PM |
3371 | INIT_LIST_HEAD(&ctx->event_list); |
3372 | atomic_set(&ctx->refcount, 1); | |
eb184479 PZ |
3373 | } |
3374 | ||
3375 | static struct perf_event_context * | |
3376 | alloc_perf_context(struct pmu *pmu, struct task_struct *task) | |
3377 | { | |
3378 | struct perf_event_context *ctx; | |
3379 | ||
3380 | ctx = kzalloc(sizeof(struct perf_event_context), GFP_KERNEL); | |
3381 | if (!ctx) | |
3382 | return NULL; | |
3383 | ||
3384 | __perf_event_init_context(ctx); | |
3385 | if (task) { | |
3386 | ctx->task = task; | |
3387 | get_task_struct(task); | |
0793a61d | 3388 | } |
eb184479 PZ |
3389 | ctx->pmu = pmu; |
3390 | ||
3391 | return ctx; | |
a63eaf34 PM |
3392 | } |
3393 | ||
2ebd4ffb MH |
3394 | static struct task_struct * |
3395 | find_lively_task_by_vpid(pid_t vpid) | |
3396 | { | |
3397 | struct task_struct *task; | |
3398 | int err; | |
0793a61d TG |
3399 | |
3400 | rcu_read_lock(); | |
2ebd4ffb | 3401 | if (!vpid) |
0793a61d TG |
3402 | task = current; |
3403 | else | |
2ebd4ffb | 3404 | task = find_task_by_vpid(vpid); |
0793a61d TG |
3405 | if (task) |
3406 | get_task_struct(task); | |
3407 | rcu_read_unlock(); | |
3408 | ||
3409 | if (!task) | |
3410 | return ERR_PTR(-ESRCH); | |
3411 | ||
0793a61d | 3412 | /* Reuse ptrace permission checks for now. */ |
c93f7669 | 3413 | err = -EACCES; |
caaee623 | 3414 | if (!ptrace_may_access(task, PTRACE_MODE_READ_REALCREDS)) |
c93f7669 PM |
3415 | goto errout; |
3416 | ||
2ebd4ffb MH |
3417 | return task; |
3418 | errout: | |
3419 | put_task_struct(task); | |
3420 | return ERR_PTR(err); | |
3421 | ||
3422 | } | |
3423 | ||
fe4b04fa PZ |
3424 | /* |
3425 | * Returns a matching context with refcount and pincount. | |
3426 | */ | |
108b02cf | 3427 | static struct perf_event_context * |
4af57ef2 YZ |
3428 | find_get_context(struct pmu *pmu, struct task_struct *task, |
3429 | struct perf_event *event) | |
0793a61d | 3430 | { |
211de6eb | 3431 | struct perf_event_context *ctx, *clone_ctx = NULL; |
22a4f650 | 3432 | struct perf_cpu_context *cpuctx; |
4af57ef2 | 3433 | void *task_ctx_data = NULL; |
25346b93 | 3434 | unsigned long flags; |
8dc85d54 | 3435 | int ctxn, err; |
4af57ef2 | 3436 | int cpu = event->cpu; |
0793a61d | 3437 | |
22a4ec72 | 3438 | if (!task) { |
cdd6c482 | 3439 | /* Must be root to operate on a CPU event: */ |
0764771d | 3440 | if (perf_paranoid_cpu() && !capable(CAP_SYS_ADMIN)) |
0793a61d TG |
3441 | return ERR_PTR(-EACCES); |
3442 | ||
0793a61d | 3443 | /* |
cdd6c482 | 3444 | * We could be clever and allow to attach a event to an |
0793a61d TG |
3445 | * offline CPU and activate it when the CPU comes up, but |
3446 | * that's for later. | |
3447 | */ | |
f6325e30 | 3448 | if (!cpu_online(cpu)) |
0793a61d TG |
3449 | return ERR_PTR(-ENODEV); |
3450 | ||
108b02cf | 3451 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); |
0793a61d | 3452 | ctx = &cpuctx->ctx; |
c93f7669 | 3453 | get_ctx(ctx); |
fe4b04fa | 3454 | ++ctx->pin_count; |
0793a61d | 3455 | |
0793a61d TG |
3456 | return ctx; |
3457 | } | |
3458 | ||
8dc85d54 PZ |
3459 | err = -EINVAL; |
3460 | ctxn = pmu->task_ctx_nr; | |
3461 | if (ctxn < 0) | |
3462 | goto errout; | |
3463 | ||
4af57ef2 YZ |
3464 | if (event->attach_state & PERF_ATTACH_TASK_DATA) { |
3465 | task_ctx_data = kzalloc(pmu->task_ctx_size, GFP_KERNEL); | |
3466 | if (!task_ctx_data) { | |
3467 | err = -ENOMEM; | |
3468 | goto errout; | |
3469 | } | |
3470 | } | |
3471 | ||
9ed6060d | 3472 | retry: |
8dc85d54 | 3473 | ctx = perf_lock_task_context(task, ctxn, &flags); |
c93f7669 | 3474 | if (ctx) { |
211de6eb | 3475 | clone_ctx = unclone_ctx(ctx); |
fe4b04fa | 3476 | ++ctx->pin_count; |
4af57ef2 YZ |
3477 | |
3478 | if (task_ctx_data && !ctx->task_ctx_data) { | |
3479 | ctx->task_ctx_data = task_ctx_data; | |
3480 | task_ctx_data = NULL; | |
3481 | } | |
e625cce1 | 3482 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
211de6eb PZ |
3483 | |
3484 | if (clone_ctx) | |
3485 | put_ctx(clone_ctx); | |
9137fb28 | 3486 | } else { |
eb184479 | 3487 | ctx = alloc_perf_context(pmu, task); |
c93f7669 PM |
3488 | err = -ENOMEM; |
3489 | if (!ctx) | |
3490 | goto errout; | |
eb184479 | 3491 | |
4af57ef2 YZ |
3492 | if (task_ctx_data) { |
3493 | ctx->task_ctx_data = task_ctx_data; | |
3494 | task_ctx_data = NULL; | |
3495 | } | |
3496 | ||
dbe08d82 ON |
3497 | err = 0; |
3498 | mutex_lock(&task->perf_event_mutex); | |
3499 | /* | |
3500 | * If it has already passed perf_event_exit_task(). | |
3501 | * we must see PF_EXITING, it takes this mutex too. | |
3502 | */ | |
3503 | if (task->flags & PF_EXITING) | |
3504 | err = -ESRCH; | |
3505 | else if (task->perf_event_ctxp[ctxn]) | |
3506 | err = -EAGAIN; | |
fe4b04fa | 3507 | else { |
9137fb28 | 3508 | get_ctx(ctx); |
fe4b04fa | 3509 | ++ctx->pin_count; |
dbe08d82 | 3510 | rcu_assign_pointer(task->perf_event_ctxp[ctxn], ctx); |
fe4b04fa | 3511 | } |
dbe08d82 ON |
3512 | mutex_unlock(&task->perf_event_mutex); |
3513 | ||
3514 | if (unlikely(err)) { | |
9137fb28 | 3515 | put_ctx(ctx); |
dbe08d82 ON |
3516 | |
3517 | if (err == -EAGAIN) | |
3518 | goto retry; | |
3519 | goto errout; | |
a63eaf34 PM |
3520 | } |
3521 | } | |
3522 | ||
4af57ef2 | 3523 | kfree(task_ctx_data); |
0793a61d | 3524 | return ctx; |
c93f7669 | 3525 | |
9ed6060d | 3526 | errout: |
4af57ef2 | 3527 | kfree(task_ctx_data); |
c93f7669 | 3528 | return ERR_PTR(err); |
0793a61d TG |
3529 | } |
3530 | ||
6fb2915d | 3531 | static void perf_event_free_filter(struct perf_event *event); |
2541517c | 3532 | static void perf_event_free_bpf_prog(struct perf_event *event); |
6fb2915d | 3533 | |
cdd6c482 | 3534 | static void free_event_rcu(struct rcu_head *head) |
592903cd | 3535 | { |
cdd6c482 | 3536 | struct perf_event *event; |
592903cd | 3537 | |
cdd6c482 IM |
3538 | event = container_of(head, struct perf_event, rcu_head); |
3539 | if (event->ns) | |
3540 | put_pid_ns(event->ns); | |
6fb2915d | 3541 | perf_event_free_filter(event); |
cdd6c482 | 3542 | kfree(event); |
592903cd PZ |
3543 | } |
3544 | ||
b69cf536 PZ |
3545 | static void ring_buffer_attach(struct perf_event *event, |
3546 | struct ring_buffer *rb); | |
925d519a | 3547 | |
4beb31f3 | 3548 | static void unaccount_event_cpu(struct perf_event *event, int cpu) |
f1600952 | 3549 | { |
4beb31f3 FW |
3550 | if (event->parent) |
3551 | return; | |
3552 | ||
4beb31f3 FW |
3553 | if (is_cgroup_event(event)) |
3554 | atomic_dec(&per_cpu(perf_cgroup_events, cpu)); | |
3555 | } | |
925d519a | 3556 | |
555e0c1e FW |
3557 | #ifdef CONFIG_NO_HZ_FULL |
3558 | static DEFINE_SPINLOCK(nr_freq_lock); | |
3559 | #endif | |
3560 | ||
3561 | static void unaccount_freq_event_nohz(void) | |
3562 | { | |
3563 | #ifdef CONFIG_NO_HZ_FULL | |
3564 | spin_lock(&nr_freq_lock); | |
3565 | if (atomic_dec_and_test(&nr_freq_events)) | |
3566 | tick_nohz_dep_clear(TICK_DEP_BIT_PERF_EVENTS); | |
3567 | spin_unlock(&nr_freq_lock); | |
3568 | #endif | |
3569 | } | |
3570 | ||
3571 | static void unaccount_freq_event(void) | |
3572 | { | |
3573 | if (tick_nohz_full_enabled()) | |
3574 | unaccount_freq_event_nohz(); | |
3575 | else | |
3576 | atomic_dec(&nr_freq_events); | |
3577 | } | |
3578 | ||
4beb31f3 FW |
3579 | static void unaccount_event(struct perf_event *event) |
3580 | { | |
25432ae9 PZ |
3581 | bool dec = false; |
3582 | ||
4beb31f3 FW |
3583 | if (event->parent) |
3584 | return; | |
3585 | ||
3586 | if (event->attach_state & PERF_ATTACH_TASK) | |
25432ae9 | 3587 | dec = true; |
4beb31f3 FW |
3588 | if (event->attr.mmap || event->attr.mmap_data) |
3589 | atomic_dec(&nr_mmap_events); | |
3590 | if (event->attr.comm) | |
3591 | atomic_dec(&nr_comm_events); | |
3592 | if (event->attr.task) | |
3593 | atomic_dec(&nr_task_events); | |
948b26b6 | 3594 | if (event->attr.freq) |
555e0c1e | 3595 | unaccount_freq_event(); |
45ac1403 | 3596 | if (event->attr.context_switch) { |
25432ae9 | 3597 | dec = true; |
45ac1403 AH |
3598 | atomic_dec(&nr_switch_events); |
3599 | } | |
4beb31f3 | 3600 | if (is_cgroup_event(event)) |
25432ae9 | 3601 | dec = true; |
4beb31f3 | 3602 | if (has_branch_stack(event)) |
25432ae9 PZ |
3603 | dec = true; |
3604 | ||
9107c89e PZ |
3605 | if (dec) { |
3606 | if (!atomic_add_unless(&perf_sched_count, -1, 1)) | |
3607 | schedule_delayed_work(&perf_sched_work, HZ); | |
3608 | } | |
4beb31f3 FW |
3609 | |
3610 | unaccount_event_cpu(event, event->cpu); | |
3611 | } | |
925d519a | 3612 | |
9107c89e PZ |
3613 | static void perf_sched_delayed(struct work_struct *work) |
3614 | { | |
3615 | mutex_lock(&perf_sched_mutex); | |
3616 | if (atomic_dec_and_test(&perf_sched_count)) | |
3617 | static_branch_disable(&perf_sched_events); | |
3618 | mutex_unlock(&perf_sched_mutex); | |
3619 | } | |
3620 | ||
bed5b25a AS |
3621 | /* |
3622 | * The following implement mutual exclusion of events on "exclusive" pmus | |
3623 | * (PERF_PMU_CAP_EXCLUSIVE). Such pmus can only have one event scheduled | |
3624 | * at a time, so we disallow creating events that might conflict, namely: | |
3625 | * | |
3626 | * 1) cpu-wide events in the presence of per-task events, | |
3627 | * 2) per-task events in the presence of cpu-wide events, | |
3628 | * 3) two matching events on the same context. | |
3629 | * | |
3630 | * The former two cases are handled in the allocation path (perf_event_alloc(), | |
a0733e69 | 3631 | * _free_event()), the latter -- before the first perf_install_in_context(). |
bed5b25a AS |
3632 | */ |
3633 | static int exclusive_event_init(struct perf_event *event) | |
3634 | { | |
3635 | struct pmu *pmu = event->pmu; | |
3636 | ||
3637 | if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE)) | |
3638 | return 0; | |
3639 | ||
3640 | /* | |
3641 | * Prevent co-existence of per-task and cpu-wide events on the | |
3642 | * same exclusive pmu. | |
3643 | * | |
3644 | * Negative pmu::exclusive_cnt means there are cpu-wide | |
3645 | * events on this "exclusive" pmu, positive means there are | |
3646 | * per-task events. | |
3647 | * | |
3648 | * Since this is called in perf_event_alloc() path, event::ctx | |
3649 | * doesn't exist yet; it is, however, safe to use PERF_ATTACH_TASK | |
3650 | * to mean "per-task event", because unlike other attach states it | |
3651 | * never gets cleared. | |
3652 | */ | |
3653 | if (event->attach_state & PERF_ATTACH_TASK) { | |
3654 | if (!atomic_inc_unless_negative(&pmu->exclusive_cnt)) | |
3655 | return -EBUSY; | |
3656 | } else { | |
3657 | if (!atomic_dec_unless_positive(&pmu->exclusive_cnt)) | |
3658 | return -EBUSY; | |
3659 | } | |
3660 | ||
3661 | return 0; | |
3662 | } | |
3663 | ||
3664 | static void exclusive_event_destroy(struct perf_event *event) | |
3665 | { | |
3666 | struct pmu *pmu = event->pmu; | |
3667 | ||
3668 | if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE)) | |
3669 | return; | |
3670 | ||
3671 | /* see comment in exclusive_event_init() */ | |
3672 | if (event->attach_state & PERF_ATTACH_TASK) | |
3673 | atomic_dec(&pmu->exclusive_cnt); | |
3674 | else | |
3675 | atomic_inc(&pmu->exclusive_cnt); | |
3676 | } | |
3677 | ||
3678 | static bool exclusive_event_match(struct perf_event *e1, struct perf_event *e2) | |
3679 | { | |
3680 | if ((e1->pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE) && | |
3681 | (e1->cpu == e2->cpu || | |
3682 | e1->cpu == -1 || | |
3683 | e2->cpu == -1)) | |
3684 | return true; | |
3685 | return false; | |
3686 | } | |
3687 | ||
3688 | /* Called under the same ctx::mutex as perf_install_in_context() */ | |
3689 | static bool exclusive_event_installable(struct perf_event *event, | |
3690 | struct perf_event_context *ctx) | |
3691 | { | |
3692 | struct perf_event *iter_event; | |
3693 | struct pmu *pmu = event->pmu; | |
3694 | ||
3695 | if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE)) | |
3696 | return true; | |
3697 | ||
3698 | list_for_each_entry(iter_event, &ctx->event_list, event_entry) { | |
3699 | if (exclusive_event_match(iter_event, event)) | |
3700 | return false; | |
3701 | } | |
3702 | ||
3703 | return true; | |
3704 | } | |
3705 | ||
683ede43 | 3706 | static void _free_event(struct perf_event *event) |
f1600952 | 3707 | { |
e360adbe | 3708 | irq_work_sync(&event->pending); |
925d519a | 3709 | |
4beb31f3 | 3710 | unaccount_event(event); |
9ee318a7 | 3711 | |
76369139 | 3712 | if (event->rb) { |
9bb5d40c PZ |
3713 | /* |
3714 | * Can happen when we close an event with re-directed output. | |
3715 | * | |
3716 | * Since we have a 0 refcount, perf_mmap_close() will skip | |
3717 | * over us; possibly making our ring_buffer_put() the last. | |
3718 | */ | |
3719 | mutex_lock(&event->mmap_mutex); | |
b69cf536 | 3720 | ring_buffer_attach(event, NULL); |
9bb5d40c | 3721 | mutex_unlock(&event->mmap_mutex); |
a4be7c27 PZ |
3722 | } |
3723 | ||
e5d1367f SE |
3724 | if (is_cgroup_event(event)) |
3725 | perf_detach_cgroup(event); | |
3726 | ||
a0733e69 PZ |
3727 | if (!event->parent) { |
3728 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) | |
3729 | put_callchain_buffers(); | |
3730 | } | |
3731 | ||
3732 | perf_event_free_bpf_prog(event); | |
3733 | ||
3734 | if (event->destroy) | |
3735 | event->destroy(event); | |
3736 | ||
3737 | if (event->ctx) | |
3738 | put_ctx(event->ctx); | |
3739 | ||
3740 | if (event->pmu) { | |
3741 | exclusive_event_destroy(event); | |
3742 | module_put(event->pmu->module); | |
3743 | } | |
3744 | ||
3745 | call_rcu(&event->rcu_head, free_event_rcu); | |
f1600952 PZ |
3746 | } |
3747 | ||
683ede43 PZ |
3748 | /* |
3749 | * Used to free events which have a known refcount of 1, such as in error paths | |
3750 | * where the event isn't exposed yet and inherited events. | |
3751 | */ | |
3752 | static void free_event(struct perf_event *event) | |
0793a61d | 3753 | { |
683ede43 PZ |
3754 | if (WARN(atomic_long_cmpxchg(&event->refcount, 1, 0) != 1, |
3755 | "unexpected event refcount: %ld; ptr=%p\n", | |
3756 | atomic_long_read(&event->refcount), event)) { | |
3757 | /* leak to avoid use-after-free */ | |
3758 | return; | |
3759 | } | |
0793a61d | 3760 | |
683ede43 | 3761 | _free_event(event); |
0793a61d TG |
3762 | } |
3763 | ||
a66a3052 | 3764 | /* |
f8697762 | 3765 | * Remove user event from the owner task. |
a66a3052 | 3766 | */ |
f8697762 | 3767 | static void perf_remove_from_owner(struct perf_event *event) |
fb0459d7 | 3768 | { |
8882135b | 3769 | struct task_struct *owner; |
fb0459d7 | 3770 | |
8882135b | 3771 | rcu_read_lock(); |
8882135b | 3772 | /* |
f47c02c0 PZ |
3773 | * Matches the smp_store_release() in perf_event_exit_task(). If we |
3774 | * observe !owner it means the list deletion is complete and we can | |
3775 | * indeed free this event, otherwise we need to serialize on | |
8882135b PZ |
3776 | * owner->perf_event_mutex. |
3777 | */ | |
f47c02c0 | 3778 | owner = lockless_dereference(event->owner); |
8882135b PZ |
3779 | if (owner) { |
3780 | /* | |
3781 | * Since delayed_put_task_struct() also drops the last | |
3782 | * task reference we can safely take a new reference | |
3783 | * while holding the rcu_read_lock(). | |
3784 | */ | |
3785 | get_task_struct(owner); | |
3786 | } | |
3787 | rcu_read_unlock(); | |
3788 | ||
3789 | if (owner) { | |
f63a8daa PZ |
3790 | /* |
3791 | * If we're here through perf_event_exit_task() we're already | |
3792 | * holding ctx->mutex which would be an inversion wrt. the | |
3793 | * normal lock order. | |
3794 | * | |
3795 | * However we can safely take this lock because its the child | |
3796 | * ctx->mutex. | |
3797 | */ | |
3798 | mutex_lock_nested(&owner->perf_event_mutex, SINGLE_DEPTH_NESTING); | |
3799 | ||
8882135b PZ |
3800 | /* |
3801 | * We have to re-check the event->owner field, if it is cleared | |
3802 | * we raced with perf_event_exit_task(), acquiring the mutex | |
3803 | * ensured they're done, and we can proceed with freeing the | |
3804 | * event. | |
3805 | */ | |
f47c02c0 | 3806 | if (event->owner) { |
8882135b | 3807 | list_del_init(&event->owner_entry); |
f47c02c0 PZ |
3808 | smp_store_release(&event->owner, NULL); |
3809 | } | |
8882135b PZ |
3810 | mutex_unlock(&owner->perf_event_mutex); |
3811 | put_task_struct(owner); | |
3812 | } | |
f8697762 JO |
3813 | } |
3814 | ||
f8697762 JO |
3815 | static void put_event(struct perf_event *event) |
3816 | { | |
f8697762 JO |
3817 | if (!atomic_long_dec_and_test(&event->refcount)) |
3818 | return; | |
3819 | ||
c6e5b732 PZ |
3820 | _free_event(event); |
3821 | } | |
3822 | ||
3823 | /* | |
3824 | * Kill an event dead; while event:refcount will preserve the event | |
3825 | * object, it will not preserve its functionality. Once the last 'user' | |
3826 | * gives up the object, we'll destroy the thing. | |
3827 | */ | |
3828 | int perf_event_release_kernel(struct perf_event *event) | |
3829 | { | |
a4f4bb6d | 3830 | struct perf_event_context *ctx = event->ctx; |
c6e5b732 PZ |
3831 | struct perf_event *child, *tmp; |
3832 | ||
a4f4bb6d PZ |
3833 | /* |
3834 | * If we got here through err_file: fput(event_file); we will not have | |
3835 | * attached to a context yet. | |
3836 | */ | |
3837 | if (!ctx) { | |
3838 | WARN_ON_ONCE(event->attach_state & | |
3839 | (PERF_ATTACH_CONTEXT|PERF_ATTACH_GROUP)); | |
3840 | goto no_ctx; | |
3841 | } | |
3842 | ||
f8697762 JO |
3843 | if (!is_kernel_event(event)) |
3844 | perf_remove_from_owner(event); | |
8882135b | 3845 | |
5fa7c8ec | 3846 | ctx = perf_event_ctx_lock(event); |
a83fe28e | 3847 | WARN_ON_ONCE(ctx->parent_ctx); |
a69b0ca4 | 3848 | perf_remove_from_context(event, DETACH_GROUP); |
683ede43 | 3849 | |
a69b0ca4 | 3850 | raw_spin_lock_irq(&ctx->lock); |
683ede43 | 3851 | /* |
a69b0ca4 PZ |
3852 | * Mark this even as STATE_DEAD, there is no external reference to it |
3853 | * anymore. | |
683ede43 | 3854 | * |
a69b0ca4 PZ |
3855 | * Anybody acquiring event->child_mutex after the below loop _must_ |
3856 | * also see this, most importantly inherit_event() which will avoid | |
3857 | * placing more children on the list. | |
683ede43 | 3858 | * |
c6e5b732 PZ |
3859 | * Thus this guarantees that we will in fact observe and kill _ALL_ |
3860 | * child events. | |
683ede43 | 3861 | */ |
a69b0ca4 PZ |
3862 | event->state = PERF_EVENT_STATE_DEAD; |
3863 | raw_spin_unlock_irq(&ctx->lock); | |
3864 | ||
3865 | perf_event_ctx_unlock(event, ctx); | |
683ede43 | 3866 | |
c6e5b732 PZ |
3867 | again: |
3868 | mutex_lock(&event->child_mutex); | |
3869 | list_for_each_entry(child, &event->child_list, child_list) { | |
a6fa941d | 3870 | |
c6e5b732 PZ |
3871 | /* |
3872 | * Cannot change, child events are not migrated, see the | |
3873 | * comment with perf_event_ctx_lock_nested(). | |
3874 | */ | |
3875 | ctx = lockless_dereference(child->ctx); | |
3876 | /* | |
3877 | * Since child_mutex nests inside ctx::mutex, we must jump | |
3878 | * through hoops. We start by grabbing a reference on the ctx. | |
3879 | * | |
3880 | * Since the event cannot get freed while we hold the | |
3881 | * child_mutex, the context must also exist and have a !0 | |
3882 | * reference count. | |
3883 | */ | |
3884 | get_ctx(ctx); | |
3885 | ||
3886 | /* | |
3887 | * Now that we have a ctx ref, we can drop child_mutex, and | |
3888 | * acquire ctx::mutex without fear of it going away. Then we | |
3889 | * can re-acquire child_mutex. | |
3890 | */ | |
3891 | mutex_unlock(&event->child_mutex); | |
3892 | mutex_lock(&ctx->mutex); | |
3893 | mutex_lock(&event->child_mutex); | |
3894 | ||
3895 | /* | |
3896 | * Now that we hold ctx::mutex and child_mutex, revalidate our | |
3897 | * state, if child is still the first entry, it didn't get freed | |
3898 | * and we can continue doing so. | |
3899 | */ | |
3900 | tmp = list_first_entry_or_null(&event->child_list, | |
3901 | struct perf_event, child_list); | |
3902 | if (tmp == child) { | |
3903 | perf_remove_from_context(child, DETACH_GROUP); | |
3904 | list_del(&child->child_list); | |
3905 | free_event(child); | |
3906 | /* | |
3907 | * This matches the refcount bump in inherit_event(); | |
3908 | * this can't be the last reference. | |
3909 | */ | |
3910 | put_event(event); | |
3911 | } | |
3912 | ||
3913 | mutex_unlock(&event->child_mutex); | |
3914 | mutex_unlock(&ctx->mutex); | |
3915 | put_ctx(ctx); | |
3916 | goto again; | |
3917 | } | |
3918 | mutex_unlock(&event->child_mutex); | |
3919 | ||
a4f4bb6d PZ |
3920 | no_ctx: |
3921 | put_event(event); /* Must be the 'last' reference */ | |
683ede43 PZ |
3922 | return 0; |
3923 | } | |
3924 | EXPORT_SYMBOL_GPL(perf_event_release_kernel); | |
3925 | ||
8b10c5e2 PZ |
3926 | /* |
3927 | * Called when the last reference to the file is gone. | |
3928 | */ | |
a6fa941d AV |
3929 | static int perf_release(struct inode *inode, struct file *file) |
3930 | { | |
c6e5b732 | 3931 | perf_event_release_kernel(file->private_data); |
a6fa941d | 3932 | return 0; |
fb0459d7 | 3933 | } |
fb0459d7 | 3934 | |
59ed446f | 3935 | u64 perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) |
e53c0994 | 3936 | { |
cdd6c482 | 3937 | struct perf_event *child; |
e53c0994 PZ |
3938 | u64 total = 0; |
3939 | ||
59ed446f PZ |
3940 | *enabled = 0; |
3941 | *running = 0; | |
3942 | ||
6f10581a | 3943 | mutex_lock(&event->child_mutex); |
01add3ea | 3944 | |
7d88962e | 3945 | (void)perf_event_read(event, false); |
01add3ea SB |
3946 | total += perf_event_count(event); |
3947 | ||
59ed446f PZ |
3948 | *enabled += event->total_time_enabled + |
3949 | atomic64_read(&event->child_total_time_enabled); | |
3950 | *running += event->total_time_running + | |
3951 | atomic64_read(&event->child_total_time_running); | |
3952 | ||
3953 | list_for_each_entry(child, &event->child_list, child_list) { | |
7d88962e | 3954 | (void)perf_event_read(child, false); |
01add3ea | 3955 | total += perf_event_count(child); |
59ed446f PZ |
3956 | *enabled += child->total_time_enabled; |
3957 | *running += child->total_time_running; | |
3958 | } | |
6f10581a | 3959 | mutex_unlock(&event->child_mutex); |
e53c0994 PZ |
3960 | |
3961 | return total; | |
3962 | } | |
fb0459d7 | 3963 | EXPORT_SYMBOL_GPL(perf_event_read_value); |
e53c0994 | 3964 | |
7d88962e | 3965 | static int __perf_read_group_add(struct perf_event *leader, |
fa8c2693 | 3966 | u64 read_format, u64 *values) |
3dab77fb | 3967 | { |
fa8c2693 PZ |
3968 | struct perf_event *sub; |
3969 | int n = 1; /* skip @nr */ | |
7d88962e | 3970 | int ret; |
f63a8daa | 3971 | |
7d88962e SB |
3972 | ret = perf_event_read(leader, true); |
3973 | if (ret) | |
3974 | return ret; | |
abf4868b | 3975 | |
fa8c2693 PZ |
3976 | /* |
3977 | * Since we co-schedule groups, {enabled,running} times of siblings | |
3978 | * will be identical to those of the leader, so we only publish one | |
3979 | * set. | |
3980 | */ | |
3981 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { | |
3982 | values[n++] += leader->total_time_enabled + | |
3983 | atomic64_read(&leader->child_total_time_enabled); | |
3984 | } | |
3dab77fb | 3985 | |
fa8c2693 PZ |
3986 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { |
3987 | values[n++] += leader->total_time_running + | |
3988 | atomic64_read(&leader->child_total_time_running); | |
3989 | } | |
3990 | ||
3991 | /* | |
3992 | * Write {count,id} tuples for every sibling. | |
3993 | */ | |
3994 | values[n++] += perf_event_count(leader); | |
abf4868b PZ |
3995 | if (read_format & PERF_FORMAT_ID) |
3996 | values[n++] = primary_event_id(leader); | |
3dab77fb | 3997 | |
fa8c2693 PZ |
3998 | list_for_each_entry(sub, &leader->sibling_list, group_entry) { |
3999 | values[n++] += perf_event_count(sub); | |
4000 | if (read_format & PERF_FORMAT_ID) | |
4001 | values[n++] = primary_event_id(sub); | |
4002 | } | |
7d88962e SB |
4003 | |
4004 | return 0; | |
fa8c2693 | 4005 | } |
3dab77fb | 4006 | |
fa8c2693 PZ |
4007 | static int perf_read_group(struct perf_event *event, |
4008 | u64 read_format, char __user *buf) | |
4009 | { | |
4010 | struct perf_event *leader = event->group_leader, *child; | |
4011 | struct perf_event_context *ctx = leader->ctx; | |
7d88962e | 4012 | int ret; |
fa8c2693 | 4013 | u64 *values; |
3dab77fb | 4014 | |
fa8c2693 | 4015 | lockdep_assert_held(&ctx->mutex); |
3dab77fb | 4016 | |
fa8c2693 PZ |
4017 | values = kzalloc(event->read_size, GFP_KERNEL); |
4018 | if (!values) | |
4019 | return -ENOMEM; | |
3dab77fb | 4020 | |
fa8c2693 PZ |
4021 | values[0] = 1 + leader->nr_siblings; |
4022 | ||
4023 | /* | |
4024 | * By locking the child_mutex of the leader we effectively | |
4025 | * lock the child list of all siblings.. XXX explain how. | |
4026 | */ | |
4027 | mutex_lock(&leader->child_mutex); | |
abf4868b | 4028 | |
7d88962e SB |
4029 | ret = __perf_read_group_add(leader, read_format, values); |
4030 | if (ret) | |
4031 | goto unlock; | |
4032 | ||
4033 | list_for_each_entry(child, &leader->child_list, child_list) { | |
4034 | ret = __perf_read_group_add(child, read_format, values); | |
4035 | if (ret) | |
4036 | goto unlock; | |
4037 | } | |
abf4868b | 4038 | |
fa8c2693 | 4039 | mutex_unlock(&leader->child_mutex); |
abf4868b | 4040 | |
7d88962e | 4041 | ret = event->read_size; |
fa8c2693 PZ |
4042 | if (copy_to_user(buf, values, event->read_size)) |
4043 | ret = -EFAULT; | |
7d88962e | 4044 | goto out; |
fa8c2693 | 4045 | |
7d88962e SB |
4046 | unlock: |
4047 | mutex_unlock(&leader->child_mutex); | |
4048 | out: | |
fa8c2693 | 4049 | kfree(values); |
abf4868b | 4050 | return ret; |
3dab77fb PZ |
4051 | } |
4052 | ||
b15f495b | 4053 | static int perf_read_one(struct perf_event *event, |
3dab77fb PZ |
4054 | u64 read_format, char __user *buf) |
4055 | { | |
59ed446f | 4056 | u64 enabled, running; |
3dab77fb PZ |
4057 | u64 values[4]; |
4058 | int n = 0; | |
4059 | ||
59ed446f PZ |
4060 | values[n++] = perf_event_read_value(event, &enabled, &running); |
4061 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
4062 | values[n++] = enabled; | |
4063 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
4064 | values[n++] = running; | |
3dab77fb | 4065 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 4066 | values[n++] = primary_event_id(event); |
3dab77fb PZ |
4067 | |
4068 | if (copy_to_user(buf, values, n * sizeof(u64))) | |
4069 | return -EFAULT; | |
4070 | ||
4071 | return n * sizeof(u64); | |
4072 | } | |
4073 | ||
dc633982 JO |
4074 | static bool is_event_hup(struct perf_event *event) |
4075 | { | |
4076 | bool no_children; | |
4077 | ||
a69b0ca4 | 4078 | if (event->state > PERF_EVENT_STATE_EXIT) |
dc633982 JO |
4079 | return false; |
4080 | ||
4081 | mutex_lock(&event->child_mutex); | |
4082 | no_children = list_empty(&event->child_list); | |
4083 | mutex_unlock(&event->child_mutex); | |
4084 | return no_children; | |
4085 | } | |
4086 | ||
0793a61d | 4087 | /* |
cdd6c482 | 4088 | * Read the performance event - simple non blocking version for now |
0793a61d TG |
4089 | */ |
4090 | static ssize_t | |
b15f495b | 4091 | __perf_read(struct perf_event *event, char __user *buf, size_t count) |
0793a61d | 4092 | { |
cdd6c482 | 4093 | u64 read_format = event->attr.read_format; |
3dab77fb | 4094 | int ret; |
0793a61d | 4095 | |
3b6f9e5c | 4096 | /* |
cdd6c482 | 4097 | * Return end-of-file for a read on a event that is in |
3b6f9e5c PM |
4098 | * error state (i.e. because it was pinned but it couldn't be |
4099 | * scheduled on to the CPU at some point). | |
4100 | */ | |
cdd6c482 | 4101 | if (event->state == PERF_EVENT_STATE_ERROR) |
3b6f9e5c PM |
4102 | return 0; |
4103 | ||
c320c7b7 | 4104 | if (count < event->read_size) |
3dab77fb PZ |
4105 | return -ENOSPC; |
4106 | ||
cdd6c482 | 4107 | WARN_ON_ONCE(event->ctx->parent_ctx); |
3dab77fb | 4108 | if (read_format & PERF_FORMAT_GROUP) |
b15f495b | 4109 | ret = perf_read_group(event, read_format, buf); |
3dab77fb | 4110 | else |
b15f495b | 4111 | ret = perf_read_one(event, read_format, buf); |
0793a61d | 4112 | |
3dab77fb | 4113 | return ret; |
0793a61d TG |
4114 | } |
4115 | ||
0793a61d TG |
4116 | static ssize_t |
4117 | perf_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) | |
4118 | { | |
cdd6c482 | 4119 | struct perf_event *event = file->private_data; |
f63a8daa PZ |
4120 | struct perf_event_context *ctx; |
4121 | int ret; | |
0793a61d | 4122 | |
f63a8daa | 4123 | ctx = perf_event_ctx_lock(event); |
b15f495b | 4124 | ret = __perf_read(event, buf, count); |
f63a8daa PZ |
4125 | perf_event_ctx_unlock(event, ctx); |
4126 | ||
4127 | return ret; | |
0793a61d TG |
4128 | } |
4129 | ||
4130 | static unsigned int perf_poll(struct file *file, poll_table *wait) | |
4131 | { | |
cdd6c482 | 4132 | struct perf_event *event = file->private_data; |
76369139 | 4133 | struct ring_buffer *rb; |
61b67684 | 4134 | unsigned int events = POLLHUP; |
c7138f37 | 4135 | |
e708d7ad | 4136 | poll_wait(file, &event->waitq, wait); |
179033b3 | 4137 | |
dc633982 | 4138 | if (is_event_hup(event)) |
179033b3 | 4139 | return events; |
c7138f37 | 4140 | |
10c6db11 | 4141 | /* |
9bb5d40c PZ |
4142 | * Pin the event->rb by taking event->mmap_mutex; otherwise |
4143 | * perf_event_set_output() can swizzle our rb and make us miss wakeups. | |
10c6db11 PZ |
4144 | */ |
4145 | mutex_lock(&event->mmap_mutex); | |
9bb5d40c PZ |
4146 | rb = event->rb; |
4147 | if (rb) | |
76369139 | 4148 | events = atomic_xchg(&rb->poll, 0); |
10c6db11 | 4149 | mutex_unlock(&event->mmap_mutex); |
0793a61d TG |
4150 | return events; |
4151 | } | |
4152 | ||
f63a8daa | 4153 | static void _perf_event_reset(struct perf_event *event) |
6de6a7b9 | 4154 | { |
7d88962e | 4155 | (void)perf_event_read(event, false); |
e7850595 | 4156 | local64_set(&event->count, 0); |
cdd6c482 | 4157 | perf_event_update_userpage(event); |
3df5edad PZ |
4158 | } |
4159 | ||
c93f7669 | 4160 | /* |
cdd6c482 IM |
4161 | * Holding the top-level event's child_mutex means that any |
4162 | * descendant process that has inherited this event will block | |
8ba289b8 | 4163 | * in perf_event_exit_event() if it goes to exit, thus satisfying the |
cdd6c482 | 4164 | * task existence requirements of perf_event_enable/disable. |
c93f7669 | 4165 | */ |
cdd6c482 IM |
4166 | static void perf_event_for_each_child(struct perf_event *event, |
4167 | void (*func)(struct perf_event *)) | |
3df5edad | 4168 | { |
cdd6c482 | 4169 | struct perf_event *child; |
3df5edad | 4170 | |
cdd6c482 | 4171 | WARN_ON_ONCE(event->ctx->parent_ctx); |
f63a8daa | 4172 | |
cdd6c482 IM |
4173 | mutex_lock(&event->child_mutex); |
4174 | func(event); | |
4175 | list_for_each_entry(child, &event->child_list, child_list) | |
3df5edad | 4176 | func(child); |
cdd6c482 | 4177 | mutex_unlock(&event->child_mutex); |
3df5edad PZ |
4178 | } |
4179 | ||
cdd6c482 IM |
4180 | static void perf_event_for_each(struct perf_event *event, |
4181 | void (*func)(struct perf_event *)) | |
3df5edad | 4182 | { |
cdd6c482 IM |
4183 | struct perf_event_context *ctx = event->ctx; |
4184 | struct perf_event *sibling; | |
3df5edad | 4185 | |
f63a8daa PZ |
4186 | lockdep_assert_held(&ctx->mutex); |
4187 | ||
cdd6c482 | 4188 | event = event->group_leader; |
75f937f2 | 4189 | |
cdd6c482 | 4190 | perf_event_for_each_child(event, func); |
cdd6c482 | 4191 | list_for_each_entry(sibling, &event->sibling_list, group_entry) |
724b6daa | 4192 | perf_event_for_each_child(sibling, func); |
6de6a7b9 PZ |
4193 | } |
4194 | ||
fae3fde6 PZ |
4195 | static void __perf_event_period(struct perf_event *event, |
4196 | struct perf_cpu_context *cpuctx, | |
4197 | struct perf_event_context *ctx, | |
4198 | void *info) | |
c7999c6f | 4199 | { |
fae3fde6 | 4200 | u64 value = *((u64 *)info); |
c7999c6f | 4201 | bool active; |
08247e31 | 4202 | |
cdd6c482 | 4203 | if (event->attr.freq) { |
cdd6c482 | 4204 | event->attr.sample_freq = value; |
08247e31 | 4205 | } else { |
cdd6c482 IM |
4206 | event->attr.sample_period = value; |
4207 | event->hw.sample_period = value; | |
08247e31 | 4208 | } |
bad7192b PZ |
4209 | |
4210 | active = (event->state == PERF_EVENT_STATE_ACTIVE); | |
4211 | if (active) { | |
4212 | perf_pmu_disable(ctx->pmu); | |
4213 | event->pmu->stop(event, PERF_EF_UPDATE); | |
4214 | } | |
4215 | ||
4216 | local64_set(&event->hw.period_left, 0); | |
4217 | ||
4218 | if (active) { | |
4219 | event->pmu->start(event, PERF_EF_RELOAD); | |
4220 | perf_pmu_enable(ctx->pmu); | |
4221 | } | |
c7999c6f PZ |
4222 | } |
4223 | ||
4224 | static int perf_event_period(struct perf_event *event, u64 __user *arg) | |
4225 | { | |
c7999c6f PZ |
4226 | u64 value; |
4227 | ||
4228 | if (!is_sampling_event(event)) | |
4229 | return -EINVAL; | |
4230 | ||
4231 | if (copy_from_user(&value, arg, sizeof(value))) | |
4232 | return -EFAULT; | |
4233 | ||
4234 | if (!value) | |
4235 | return -EINVAL; | |
4236 | ||
4237 | if (event->attr.freq && value > sysctl_perf_event_sample_rate) | |
4238 | return -EINVAL; | |
4239 | ||
fae3fde6 | 4240 | event_function_call(event, __perf_event_period, &value); |
08247e31 | 4241 | |
c7999c6f | 4242 | return 0; |
08247e31 PZ |
4243 | } |
4244 | ||
ac9721f3 PZ |
4245 | static const struct file_operations perf_fops; |
4246 | ||
2903ff01 | 4247 | static inline int perf_fget_light(int fd, struct fd *p) |
ac9721f3 | 4248 | { |
2903ff01 AV |
4249 | struct fd f = fdget(fd); |
4250 | if (!f.file) | |
4251 | return -EBADF; | |
ac9721f3 | 4252 | |
2903ff01 AV |
4253 | if (f.file->f_op != &perf_fops) { |
4254 | fdput(f); | |
4255 | return -EBADF; | |
ac9721f3 | 4256 | } |
2903ff01 AV |
4257 | *p = f; |
4258 | return 0; | |
ac9721f3 PZ |
4259 | } |
4260 | ||
4261 | static int perf_event_set_output(struct perf_event *event, | |
4262 | struct perf_event *output_event); | |
6fb2915d | 4263 | static int perf_event_set_filter(struct perf_event *event, void __user *arg); |
2541517c | 4264 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd); |
a4be7c27 | 4265 | |
f63a8daa | 4266 | static long _perf_ioctl(struct perf_event *event, unsigned int cmd, unsigned long arg) |
d859e29f | 4267 | { |
cdd6c482 | 4268 | void (*func)(struct perf_event *); |
3df5edad | 4269 | u32 flags = arg; |
d859e29f PM |
4270 | |
4271 | switch (cmd) { | |
cdd6c482 | 4272 | case PERF_EVENT_IOC_ENABLE: |
f63a8daa | 4273 | func = _perf_event_enable; |
d859e29f | 4274 | break; |
cdd6c482 | 4275 | case PERF_EVENT_IOC_DISABLE: |
f63a8daa | 4276 | func = _perf_event_disable; |
79f14641 | 4277 | break; |
cdd6c482 | 4278 | case PERF_EVENT_IOC_RESET: |
f63a8daa | 4279 | func = _perf_event_reset; |
6de6a7b9 | 4280 | break; |
3df5edad | 4281 | |
cdd6c482 | 4282 | case PERF_EVENT_IOC_REFRESH: |
f63a8daa | 4283 | return _perf_event_refresh(event, arg); |
08247e31 | 4284 | |
cdd6c482 IM |
4285 | case PERF_EVENT_IOC_PERIOD: |
4286 | return perf_event_period(event, (u64 __user *)arg); | |
08247e31 | 4287 | |
cf4957f1 JO |
4288 | case PERF_EVENT_IOC_ID: |
4289 | { | |
4290 | u64 id = primary_event_id(event); | |
4291 | ||
4292 | if (copy_to_user((void __user *)arg, &id, sizeof(id))) | |
4293 | return -EFAULT; | |
4294 | return 0; | |
4295 | } | |
4296 | ||
cdd6c482 | 4297 | case PERF_EVENT_IOC_SET_OUTPUT: |
ac9721f3 | 4298 | { |
ac9721f3 | 4299 | int ret; |
ac9721f3 | 4300 | if (arg != -1) { |
2903ff01 AV |
4301 | struct perf_event *output_event; |
4302 | struct fd output; | |
4303 | ret = perf_fget_light(arg, &output); | |
4304 | if (ret) | |
4305 | return ret; | |
4306 | output_event = output.file->private_data; | |
4307 | ret = perf_event_set_output(event, output_event); | |
4308 | fdput(output); | |
4309 | } else { | |
4310 | ret = perf_event_set_output(event, NULL); | |
ac9721f3 | 4311 | } |
ac9721f3 PZ |
4312 | return ret; |
4313 | } | |
a4be7c27 | 4314 | |
6fb2915d LZ |
4315 | case PERF_EVENT_IOC_SET_FILTER: |
4316 | return perf_event_set_filter(event, (void __user *)arg); | |
4317 | ||
2541517c AS |
4318 | case PERF_EVENT_IOC_SET_BPF: |
4319 | return perf_event_set_bpf_prog(event, arg); | |
4320 | ||
d859e29f | 4321 | default: |
3df5edad | 4322 | return -ENOTTY; |
d859e29f | 4323 | } |
3df5edad PZ |
4324 | |
4325 | if (flags & PERF_IOC_FLAG_GROUP) | |
cdd6c482 | 4326 | perf_event_for_each(event, func); |
3df5edad | 4327 | else |
cdd6c482 | 4328 | perf_event_for_each_child(event, func); |
3df5edad PZ |
4329 | |
4330 | return 0; | |
d859e29f PM |
4331 | } |
4332 | ||
f63a8daa PZ |
4333 | static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
4334 | { | |
4335 | struct perf_event *event = file->private_data; | |
4336 | struct perf_event_context *ctx; | |
4337 | long ret; | |
4338 | ||
4339 | ctx = perf_event_ctx_lock(event); | |
4340 | ret = _perf_ioctl(event, cmd, arg); | |
4341 | perf_event_ctx_unlock(event, ctx); | |
4342 | ||
4343 | return ret; | |
4344 | } | |
4345 | ||
b3f20785 PM |
4346 | #ifdef CONFIG_COMPAT |
4347 | static long perf_compat_ioctl(struct file *file, unsigned int cmd, | |
4348 | unsigned long arg) | |
4349 | { | |
4350 | switch (_IOC_NR(cmd)) { | |
4351 | case _IOC_NR(PERF_EVENT_IOC_SET_FILTER): | |
4352 | case _IOC_NR(PERF_EVENT_IOC_ID): | |
4353 | /* Fix up pointer size (usually 4 -> 8 in 32-on-64-bit case */ | |
4354 | if (_IOC_SIZE(cmd) == sizeof(compat_uptr_t)) { | |
4355 | cmd &= ~IOCSIZE_MASK; | |
4356 | cmd |= sizeof(void *) << IOCSIZE_SHIFT; | |
4357 | } | |
4358 | break; | |
4359 | } | |
4360 | return perf_ioctl(file, cmd, arg); | |
4361 | } | |
4362 | #else | |
4363 | # define perf_compat_ioctl NULL | |
4364 | #endif | |
4365 | ||
cdd6c482 | 4366 | int perf_event_task_enable(void) |
771d7cde | 4367 | { |
f63a8daa | 4368 | struct perf_event_context *ctx; |
cdd6c482 | 4369 | struct perf_event *event; |
771d7cde | 4370 | |
cdd6c482 | 4371 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
4372 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
4373 | ctx = perf_event_ctx_lock(event); | |
4374 | perf_event_for_each_child(event, _perf_event_enable); | |
4375 | perf_event_ctx_unlock(event, ctx); | |
4376 | } | |
cdd6c482 | 4377 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
4378 | |
4379 | return 0; | |
4380 | } | |
4381 | ||
cdd6c482 | 4382 | int perf_event_task_disable(void) |
771d7cde | 4383 | { |
f63a8daa | 4384 | struct perf_event_context *ctx; |
cdd6c482 | 4385 | struct perf_event *event; |
771d7cde | 4386 | |
cdd6c482 | 4387 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
4388 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
4389 | ctx = perf_event_ctx_lock(event); | |
4390 | perf_event_for_each_child(event, _perf_event_disable); | |
4391 | perf_event_ctx_unlock(event, ctx); | |
4392 | } | |
cdd6c482 | 4393 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
4394 | |
4395 | return 0; | |
4396 | } | |
4397 | ||
cdd6c482 | 4398 | static int perf_event_index(struct perf_event *event) |
194002b2 | 4399 | { |
a4eaf7f1 PZ |
4400 | if (event->hw.state & PERF_HES_STOPPED) |
4401 | return 0; | |
4402 | ||
cdd6c482 | 4403 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
194002b2 PZ |
4404 | return 0; |
4405 | ||
35edc2a5 | 4406 | return event->pmu->event_idx(event); |
194002b2 PZ |
4407 | } |
4408 | ||
c4794295 | 4409 | static void calc_timer_values(struct perf_event *event, |
e3f3541c | 4410 | u64 *now, |
7f310a5d EM |
4411 | u64 *enabled, |
4412 | u64 *running) | |
c4794295 | 4413 | { |
e3f3541c | 4414 | u64 ctx_time; |
c4794295 | 4415 | |
e3f3541c PZ |
4416 | *now = perf_clock(); |
4417 | ctx_time = event->shadow_ctx_time + *now; | |
c4794295 EM |
4418 | *enabled = ctx_time - event->tstamp_enabled; |
4419 | *running = ctx_time - event->tstamp_running; | |
4420 | } | |
4421 | ||
fa731587 PZ |
4422 | static void perf_event_init_userpage(struct perf_event *event) |
4423 | { | |
4424 | struct perf_event_mmap_page *userpg; | |
4425 | struct ring_buffer *rb; | |
4426 | ||
4427 | rcu_read_lock(); | |
4428 | rb = rcu_dereference(event->rb); | |
4429 | if (!rb) | |
4430 | goto unlock; | |
4431 | ||
4432 | userpg = rb->user_page; | |
4433 | ||
4434 | /* Allow new userspace to detect that bit 0 is deprecated */ | |
4435 | userpg->cap_bit0_is_deprecated = 1; | |
4436 | userpg->size = offsetof(struct perf_event_mmap_page, __reserved); | |
e8c6deac AS |
4437 | userpg->data_offset = PAGE_SIZE; |
4438 | userpg->data_size = perf_data_size(rb); | |
fa731587 PZ |
4439 | |
4440 | unlock: | |
4441 | rcu_read_unlock(); | |
4442 | } | |
4443 | ||
c1317ec2 AL |
4444 | void __weak arch_perf_update_userpage( |
4445 | struct perf_event *event, struct perf_event_mmap_page *userpg, u64 now) | |
e3f3541c PZ |
4446 | { |
4447 | } | |
4448 | ||
38ff667b PZ |
4449 | /* |
4450 | * Callers need to ensure there can be no nesting of this function, otherwise | |
4451 | * the seqlock logic goes bad. We can not serialize this because the arch | |
4452 | * code calls this from NMI context. | |
4453 | */ | |
cdd6c482 | 4454 | void perf_event_update_userpage(struct perf_event *event) |
37d81828 | 4455 | { |
cdd6c482 | 4456 | struct perf_event_mmap_page *userpg; |
76369139 | 4457 | struct ring_buffer *rb; |
e3f3541c | 4458 | u64 enabled, running, now; |
38ff667b PZ |
4459 | |
4460 | rcu_read_lock(); | |
5ec4c599 PZ |
4461 | rb = rcu_dereference(event->rb); |
4462 | if (!rb) | |
4463 | goto unlock; | |
4464 | ||
0d641208 EM |
4465 | /* |
4466 | * compute total_time_enabled, total_time_running | |
4467 | * based on snapshot values taken when the event | |
4468 | * was last scheduled in. | |
4469 | * | |
4470 | * we cannot simply called update_context_time() | |
4471 | * because of locking issue as we can be called in | |
4472 | * NMI context | |
4473 | */ | |
e3f3541c | 4474 | calc_timer_values(event, &now, &enabled, &running); |
38ff667b | 4475 | |
76369139 | 4476 | userpg = rb->user_page; |
7b732a75 PZ |
4477 | /* |
4478 | * Disable preemption so as to not let the corresponding user-space | |
4479 | * spin too long if we get preempted. | |
4480 | */ | |
4481 | preempt_disable(); | |
37d81828 | 4482 | ++userpg->lock; |
92f22a38 | 4483 | barrier(); |
cdd6c482 | 4484 | userpg->index = perf_event_index(event); |
b5e58793 | 4485 | userpg->offset = perf_event_count(event); |
365a4038 | 4486 | if (userpg->index) |
e7850595 | 4487 | userpg->offset -= local64_read(&event->hw.prev_count); |
7b732a75 | 4488 | |
0d641208 | 4489 | userpg->time_enabled = enabled + |
cdd6c482 | 4490 | atomic64_read(&event->child_total_time_enabled); |
7f8b4e4e | 4491 | |
0d641208 | 4492 | userpg->time_running = running + |
cdd6c482 | 4493 | atomic64_read(&event->child_total_time_running); |
7f8b4e4e | 4494 | |
c1317ec2 | 4495 | arch_perf_update_userpage(event, userpg, now); |
e3f3541c | 4496 | |
92f22a38 | 4497 | barrier(); |
37d81828 | 4498 | ++userpg->lock; |
7b732a75 | 4499 | preempt_enable(); |
38ff667b | 4500 | unlock: |
7b732a75 | 4501 | rcu_read_unlock(); |
37d81828 PM |
4502 | } |
4503 | ||
906010b2 PZ |
4504 | static int perf_mmap_fault(struct vm_area_struct *vma, struct vm_fault *vmf) |
4505 | { | |
4506 | struct perf_event *event = vma->vm_file->private_data; | |
76369139 | 4507 | struct ring_buffer *rb; |
906010b2 PZ |
4508 | int ret = VM_FAULT_SIGBUS; |
4509 | ||
4510 | if (vmf->flags & FAULT_FLAG_MKWRITE) { | |
4511 | if (vmf->pgoff == 0) | |
4512 | ret = 0; | |
4513 | return ret; | |
4514 | } | |
4515 | ||
4516 | rcu_read_lock(); | |
76369139 FW |
4517 | rb = rcu_dereference(event->rb); |
4518 | if (!rb) | |
906010b2 PZ |
4519 | goto unlock; |
4520 | ||
4521 | if (vmf->pgoff && (vmf->flags & FAULT_FLAG_WRITE)) | |
4522 | goto unlock; | |
4523 | ||
76369139 | 4524 | vmf->page = perf_mmap_to_page(rb, vmf->pgoff); |
906010b2 PZ |
4525 | if (!vmf->page) |
4526 | goto unlock; | |
4527 | ||
4528 | get_page(vmf->page); | |
4529 | vmf->page->mapping = vma->vm_file->f_mapping; | |
4530 | vmf->page->index = vmf->pgoff; | |
4531 | ||
4532 | ret = 0; | |
4533 | unlock: | |
4534 | rcu_read_unlock(); | |
4535 | ||
4536 | return ret; | |
4537 | } | |
4538 | ||
10c6db11 PZ |
4539 | static void ring_buffer_attach(struct perf_event *event, |
4540 | struct ring_buffer *rb) | |
4541 | { | |
b69cf536 | 4542 | struct ring_buffer *old_rb = NULL; |
10c6db11 PZ |
4543 | unsigned long flags; |
4544 | ||
b69cf536 PZ |
4545 | if (event->rb) { |
4546 | /* | |
4547 | * Should be impossible, we set this when removing | |
4548 | * event->rb_entry and wait/clear when adding event->rb_entry. | |
4549 | */ | |
4550 | WARN_ON_ONCE(event->rcu_pending); | |
10c6db11 | 4551 | |
b69cf536 | 4552 | old_rb = event->rb; |
b69cf536 PZ |
4553 | spin_lock_irqsave(&old_rb->event_lock, flags); |
4554 | list_del_rcu(&event->rb_entry); | |
4555 | spin_unlock_irqrestore(&old_rb->event_lock, flags); | |
10c6db11 | 4556 | |
2f993cf0 ON |
4557 | event->rcu_batches = get_state_synchronize_rcu(); |
4558 | event->rcu_pending = 1; | |
b69cf536 | 4559 | } |
10c6db11 | 4560 | |
b69cf536 | 4561 | if (rb) { |
2f993cf0 ON |
4562 | if (event->rcu_pending) { |
4563 | cond_synchronize_rcu(event->rcu_batches); | |
4564 | event->rcu_pending = 0; | |
4565 | } | |
4566 | ||
b69cf536 PZ |
4567 | spin_lock_irqsave(&rb->event_lock, flags); |
4568 | list_add_rcu(&event->rb_entry, &rb->event_list); | |
4569 | spin_unlock_irqrestore(&rb->event_lock, flags); | |
4570 | } | |
4571 | ||
4572 | rcu_assign_pointer(event->rb, rb); | |
4573 | ||
4574 | if (old_rb) { | |
4575 | ring_buffer_put(old_rb); | |
4576 | /* | |
4577 | * Since we detached before setting the new rb, so that we | |
4578 | * could attach the new rb, we could have missed a wakeup. | |
4579 | * Provide it now. | |
4580 | */ | |
4581 | wake_up_all(&event->waitq); | |
4582 | } | |
10c6db11 PZ |
4583 | } |
4584 | ||
4585 | static void ring_buffer_wakeup(struct perf_event *event) | |
4586 | { | |
4587 | struct ring_buffer *rb; | |
4588 | ||
4589 | rcu_read_lock(); | |
4590 | rb = rcu_dereference(event->rb); | |
9bb5d40c PZ |
4591 | if (rb) { |
4592 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) | |
4593 | wake_up_all(&event->waitq); | |
4594 | } | |
10c6db11 PZ |
4595 | rcu_read_unlock(); |
4596 | } | |
4597 | ||
fdc26706 | 4598 | struct ring_buffer *ring_buffer_get(struct perf_event *event) |
7b732a75 | 4599 | { |
76369139 | 4600 | struct ring_buffer *rb; |
7b732a75 | 4601 | |
ac9721f3 | 4602 | rcu_read_lock(); |
76369139 FW |
4603 | rb = rcu_dereference(event->rb); |
4604 | if (rb) { | |
4605 | if (!atomic_inc_not_zero(&rb->refcount)) | |
4606 | rb = NULL; | |
ac9721f3 PZ |
4607 | } |
4608 | rcu_read_unlock(); | |
4609 | ||
76369139 | 4610 | return rb; |
ac9721f3 PZ |
4611 | } |
4612 | ||
fdc26706 | 4613 | void ring_buffer_put(struct ring_buffer *rb) |
ac9721f3 | 4614 | { |
76369139 | 4615 | if (!atomic_dec_and_test(&rb->refcount)) |
ac9721f3 | 4616 | return; |
7b732a75 | 4617 | |
9bb5d40c | 4618 | WARN_ON_ONCE(!list_empty(&rb->event_list)); |
10c6db11 | 4619 | |
76369139 | 4620 | call_rcu(&rb->rcu_head, rb_free_rcu); |
7b732a75 PZ |
4621 | } |
4622 | ||
4623 | static void perf_mmap_open(struct vm_area_struct *vma) | |
4624 | { | |
cdd6c482 | 4625 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 4626 | |
cdd6c482 | 4627 | atomic_inc(&event->mmap_count); |
9bb5d40c | 4628 | atomic_inc(&event->rb->mmap_count); |
1e0fb9ec | 4629 | |
45bfb2e5 PZ |
4630 | if (vma->vm_pgoff) |
4631 | atomic_inc(&event->rb->aux_mmap_count); | |
4632 | ||
1e0fb9ec AL |
4633 | if (event->pmu->event_mapped) |
4634 | event->pmu->event_mapped(event); | |
7b732a75 PZ |
4635 | } |
4636 | ||
9bb5d40c PZ |
4637 | /* |
4638 | * A buffer can be mmap()ed multiple times; either directly through the same | |
4639 | * event, or through other events by use of perf_event_set_output(). | |
4640 | * | |
4641 | * In order to undo the VM accounting done by perf_mmap() we need to destroy | |
4642 | * the buffer here, where we still have a VM context. This means we need | |
4643 | * to detach all events redirecting to us. | |
4644 | */ | |
7b732a75 PZ |
4645 | static void perf_mmap_close(struct vm_area_struct *vma) |
4646 | { | |
cdd6c482 | 4647 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 4648 | |
b69cf536 | 4649 | struct ring_buffer *rb = ring_buffer_get(event); |
9bb5d40c PZ |
4650 | struct user_struct *mmap_user = rb->mmap_user; |
4651 | int mmap_locked = rb->mmap_locked; | |
4652 | unsigned long size = perf_data_size(rb); | |
789f90fc | 4653 | |
1e0fb9ec AL |
4654 | if (event->pmu->event_unmapped) |
4655 | event->pmu->event_unmapped(event); | |
4656 | ||
45bfb2e5 PZ |
4657 | /* |
4658 | * rb->aux_mmap_count will always drop before rb->mmap_count and | |
4659 | * event->mmap_count, so it is ok to use event->mmap_mutex to | |
4660 | * serialize with perf_mmap here. | |
4661 | */ | |
4662 | if (rb_has_aux(rb) && vma->vm_pgoff == rb->aux_pgoff && | |
4663 | atomic_dec_and_mutex_lock(&rb->aux_mmap_count, &event->mmap_mutex)) { | |
4664 | atomic_long_sub(rb->aux_nr_pages, &mmap_user->locked_vm); | |
4665 | vma->vm_mm->pinned_vm -= rb->aux_mmap_locked; | |
4666 | ||
4667 | rb_free_aux(rb); | |
4668 | mutex_unlock(&event->mmap_mutex); | |
4669 | } | |
4670 | ||
9bb5d40c PZ |
4671 | atomic_dec(&rb->mmap_count); |
4672 | ||
4673 | if (!atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex)) | |
b69cf536 | 4674 | goto out_put; |
9bb5d40c | 4675 | |
b69cf536 | 4676 | ring_buffer_attach(event, NULL); |
9bb5d40c PZ |
4677 | mutex_unlock(&event->mmap_mutex); |
4678 | ||
4679 | /* If there's still other mmap()s of this buffer, we're done. */ | |
b69cf536 PZ |
4680 | if (atomic_read(&rb->mmap_count)) |
4681 | goto out_put; | |
ac9721f3 | 4682 | |
9bb5d40c PZ |
4683 | /* |
4684 | * No other mmap()s, detach from all other events that might redirect | |
4685 | * into the now unreachable buffer. Somewhat complicated by the | |
4686 | * fact that rb::event_lock otherwise nests inside mmap_mutex. | |
4687 | */ | |
4688 | again: | |
4689 | rcu_read_lock(); | |
4690 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) { | |
4691 | if (!atomic_long_inc_not_zero(&event->refcount)) { | |
4692 | /* | |
4693 | * This event is en-route to free_event() which will | |
4694 | * detach it and remove it from the list. | |
4695 | */ | |
4696 | continue; | |
4697 | } | |
4698 | rcu_read_unlock(); | |
789f90fc | 4699 | |
9bb5d40c PZ |
4700 | mutex_lock(&event->mmap_mutex); |
4701 | /* | |
4702 | * Check we didn't race with perf_event_set_output() which can | |
4703 | * swizzle the rb from under us while we were waiting to | |
4704 | * acquire mmap_mutex. | |
4705 | * | |
4706 | * If we find a different rb; ignore this event, a next | |
4707 | * iteration will no longer find it on the list. We have to | |
4708 | * still restart the iteration to make sure we're not now | |
4709 | * iterating the wrong list. | |
4710 | */ | |
b69cf536 PZ |
4711 | if (event->rb == rb) |
4712 | ring_buffer_attach(event, NULL); | |
4713 | ||
cdd6c482 | 4714 | mutex_unlock(&event->mmap_mutex); |
9bb5d40c | 4715 | put_event(event); |
ac9721f3 | 4716 | |
9bb5d40c PZ |
4717 | /* |
4718 | * Restart the iteration; either we're on the wrong list or | |
4719 | * destroyed its integrity by doing a deletion. | |
4720 | */ | |
4721 | goto again; | |
7b732a75 | 4722 | } |
9bb5d40c PZ |
4723 | rcu_read_unlock(); |
4724 | ||
4725 | /* | |
4726 | * It could be there's still a few 0-ref events on the list; they'll | |
4727 | * get cleaned up by free_event() -- they'll also still have their | |
4728 | * ref on the rb and will free it whenever they are done with it. | |
4729 | * | |
4730 | * Aside from that, this buffer is 'fully' detached and unmapped, | |
4731 | * undo the VM accounting. | |
4732 | */ | |
4733 | ||
4734 | atomic_long_sub((size >> PAGE_SHIFT) + 1, &mmap_user->locked_vm); | |
4735 | vma->vm_mm->pinned_vm -= mmap_locked; | |
4736 | free_uid(mmap_user); | |
4737 | ||
b69cf536 | 4738 | out_put: |
9bb5d40c | 4739 | ring_buffer_put(rb); /* could be last */ |
37d81828 PM |
4740 | } |
4741 | ||
f0f37e2f | 4742 | static const struct vm_operations_struct perf_mmap_vmops = { |
43a21ea8 | 4743 | .open = perf_mmap_open, |
45bfb2e5 | 4744 | .close = perf_mmap_close, /* non mergable */ |
43a21ea8 PZ |
4745 | .fault = perf_mmap_fault, |
4746 | .page_mkwrite = perf_mmap_fault, | |
37d81828 PM |
4747 | }; |
4748 | ||
4749 | static int perf_mmap(struct file *file, struct vm_area_struct *vma) | |
4750 | { | |
cdd6c482 | 4751 | struct perf_event *event = file->private_data; |
22a4f650 | 4752 | unsigned long user_locked, user_lock_limit; |
789f90fc | 4753 | struct user_struct *user = current_user(); |
22a4f650 | 4754 | unsigned long locked, lock_limit; |
45bfb2e5 | 4755 | struct ring_buffer *rb = NULL; |
7b732a75 PZ |
4756 | unsigned long vma_size; |
4757 | unsigned long nr_pages; | |
45bfb2e5 | 4758 | long user_extra = 0, extra = 0; |
d57e34fd | 4759 | int ret = 0, flags = 0; |
37d81828 | 4760 | |
c7920614 PZ |
4761 | /* |
4762 | * Don't allow mmap() of inherited per-task counters. This would | |
4763 | * create a performance issue due to all children writing to the | |
76369139 | 4764 | * same rb. |
c7920614 PZ |
4765 | */ |
4766 | if (event->cpu == -1 && event->attr.inherit) | |
4767 | return -EINVAL; | |
4768 | ||
43a21ea8 | 4769 | if (!(vma->vm_flags & VM_SHARED)) |
37d81828 | 4770 | return -EINVAL; |
7b732a75 PZ |
4771 | |
4772 | vma_size = vma->vm_end - vma->vm_start; | |
45bfb2e5 PZ |
4773 | |
4774 | if (vma->vm_pgoff == 0) { | |
4775 | nr_pages = (vma_size / PAGE_SIZE) - 1; | |
4776 | } else { | |
4777 | /* | |
4778 | * AUX area mapping: if rb->aux_nr_pages != 0, it's already | |
4779 | * mapped, all subsequent mappings should have the same size | |
4780 | * and offset. Must be above the normal perf buffer. | |
4781 | */ | |
4782 | u64 aux_offset, aux_size; | |
4783 | ||
4784 | if (!event->rb) | |
4785 | return -EINVAL; | |
4786 | ||
4787 | nr_pages = vma_size / PAGE_SIZE; | |
4788 | ||
4789 | mutex_lock(&event->mmap_mutex); | |
4790 | ret = -EINVAL; | |
4791 | ||
4792 | rb = event->rb; | |
4793 | if (!rb) | |
4794 | goto aux_unlock; | |
4795 | ||
4796 | aux_offset = ACCESS_ONCE(rb->user_page->aux_offset); | |
4797 | aux_size = ACCESS_ONCE(rb->user_page->aux_size); | |
4798 | ||
4799 | if (aux_offset < perf_data_size(rb) + PAGE_SIZE) | |
4800 | goto aux_unlock; | |
4801 | ||
4802 | if (aux_offset != vma->vm_pgoff << PAGE_SHIFT) | |
4803 | goto aux_unlock; | |
4804 | ||
4805 | /* already mapped with a different offset */ | |
4806 | if (rb_has_aux(rb) && rb->aux_pgoff != vma->vm_pgoff) | |
4807 | goto aux_unlock; | |
4808 | ||
4809 | if (aux_size != vma_size || aux_size != nr_pages * PAGE_SIZE) | |
4810 | goto aux_unlock; | |
4811 | ||
4812 | /* already mapped with a different size */ | |
4813 | if (rb_has_aux(rb) && rb->aux_nr_pages != nr_pages) | |
4814 | goto aux_unlock; | |
4815 | ||
4816 | if (!is_power_of_2(nr_pages)) | |
4817 | goto aux_unlock; | |
4818 | ||
4819 | if (!atomic_inc_not_zero(&rb->mmap_count)) | |
4820 | goto aux_unlock; | |
4821 | ||
4822 | if (rb_has_aux(rb)) { | |
4823 | atomic_inc(&rb->aux_mmap_count); | |
4824 | ret = 0; | |
4825 | goto unlock; | |
4826 | } | |
4827 | ||
4828 | atomic_set(&rb->aux_mmap_count, 1); | |
4829 | user_extra = nr_pages; | |
4830 | ||
4831 | goto accounting; | |
4832 | } | |
7b732a75 | 4833 | |
7730d865 | 4834 | /* |
76369139 | 4835 | * If we have rb pages ensure they're a power-of-two number, so we |
7730d865 PZ |
4836 | * can do bitmasks instead of modulo. |
4837 | */ | |
2ed11312 | 4838 | if (nr_pages != 0 && !is_power_of_2(nr_pages)) |
37d81828 PM |
4839 | return -EINVAL; |
4840 | ||
7b732a75 | 4841 | if (vma_size != PAGE_SIZE * (1 + nr_pages)) |
37d81828 PM |
4842 | return -EINVAL; |
4843 | ||
cdd6c482 | 4844 | WARN_ON_ONCE(event->ctx->parent_ctx); |
9bb5d40c | 4845 | again: |
cdd6c482 | 4846 | mutex_lock(&event->mmap_mutex); |
76369139 | 4847 | if (event->rb) { |
9bb5d40c | 4848 | if (event->rb->nr_pages != nr_pages) { |
ebb3c4c4 | 4849 | ret = -EINVAL; |
9bb5d40c PZ |
4850 | goto unlock; |
4851 | } | |
4852 | ||
4853 | if (!atomic_inc_not_zero(&event->rb->mmap_count)) { | |
4854 | /* | |
4855 | * Raced against perf_mmap_close() through | |
4856 | * perf_event_set_output(). Try again, hope for better | |
4857 | * luck. | |
4858 | */ | |
4859 | mutex_unlock(&event->mmap_mutex); | |
4860 | goto again; | |
4861 | } | |
4862 | ||
ebb3c4c4 PZ |
4863 | goto unlock; |
4864 | } | |
4865 | ||
789f90fc | 4866 | user_extra = nr_pages + 1; |
45bfb2e5 PZ |
4867 | |
4868 | accounting: | |
cdd6c482 | 4869 | user_lock_limit = sysctl_perf_event_mlock >> (PAGE_SHIFT - 10); |
a3862d3f IM |
4870 | |
4871 | /* | |
4872 | * Increase the limit linearly with more CPUs: | |
4873 | */ | |
4874 | user_lock_limit *= num_online_cpus(); | |
4875 | ||
789f90fc | 4876 | user_locked = atomic_long_read(&user->locked_vm) + user_extra; |
c5078f78 | 4877 | |
789f90fc PZ |
4878 | if (user_locked > user_lock_limit) |
4879 | extra = user_locked - user_lock_limit; | |
7b732a75 | 4880 | |
78d7d407 | 4881 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
7b732a75 | 4882 | lock_limit >>= PAGE_SHIFT; |
bc3e53f6 | 4883 | locked = vma->vm_mm->pinned_vm + extra; |
7b732a75 | 4884 | |
459ec28a IM |
4885 | if ((locked > lock_limit) && perf_paranoid_tracepoint_raw() && |
4886 | !capable(CAP_IPC_LOCK)) { | |
ebb3c4c4 PZ |
4887 | ret = -EPERM; |
4888 | goto unlock; | |
4889 | } | |
7b732a75 | 4890 | |
45bfb2e5 | 4891 | WARN_ON(!rb && event->rb); |
906010b2 | 4892 | |
d57e34fd | 4893 | if (vma->vm_flags & VM_WRITE) |
76369139 | 4894 | flags |= RING_BUFFER_WRITABLE; |
d57e34fd | 4895 | |
76369139 | 4896 | if (!rb) { |
45bfb2e5 PZ |
4897 | rb = rb_alloc(nr_pages, |
4898 | event->attr.watermark ? event->attr.wakeup_watermark : 0, | |
4899 | event->cpu, flags); | |
26cb63ad | 4900 | |
45bfb2e5 PZ |
4901 | if (!rb) { |
4902 | ret = -ENOMEM; | |
4903 | goto unlock; | |
4904 | } | |
43a21ea8 | 4905 | |
45bfb2e5 PZ |
4906 | atomic_set(&rb->mmap_count, 1); |
4907 | rb->mmap_user = get_current_user(); | |
4908 | rb->mmap_locked = extra; | |
26cb63ad | 4909 | |
45bfb2e5 | 4910 | ring_buffer_attach(event, rb); |
ac9721f3 | 4911 | |
45bfb2e5 PZ |
4912 | perf_event_init_userpage(event); |
4913 | perf_event_update_userpage(event); | |
4914 | } else { | |
1a594131 AS |
4915 | ret = rb_alloc_aux(rb, event, vma->vm_pgoff, nr_pages, |
4916 | event->attr.aux_watermark, flags); | |
45bfb2e5 PZ |
4917 | if (!ret) |
4918 | rb->aux_mmap_locked = extra; | |
4919 | } | |
9a0f05cb | 4920 | |
ebb3c4c4 | 4921 | unlock: |
45bfb2e5 PZ |
4922 | if (!ret) { |
4923 | atomic_long_add(user_extra, &user->locked_vm); | |
4924 | vma->vm_mm->pinned_vm += extra; | |
4925 | ||
ac9721f3 | 4926 | atomic_inc(&event->mmap_count); |
45bfb2e5 PZ |
4927 | } else if (rb) { |
4928 | atomic_dec(&rb->mmap_count); | |
4929 | } | |
4930 | aux_unlock: | |
cdd6c482 | 4931 | mutex_unlock(&event->mmap_mutex); |
37d81828 | 4932 | |
9bb5d40c PZ |
4933 | /* |
4934 | * Since pinned accounting is per vm we cannot allow fork() to copy our | |
4935 | * vma. | |
4936 | */ | |
26cb63ad | 4937 | vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND | VM_DONTDUMP; |
37d81828 | 4938 | vma->vm_ops = &perf_mmap_vmops; |
7b732a75 | 4939 | |
1e0fb9ec AL |
4940 | if (event->pmu->event_mapped) |
4941 | event->pmu->event_mapped(event); | |
4942 | ||
7b732a75 | 4943 | return ret; |
37d81828 PM |
4944 | } |
4945 | ||
3c446b3d PZ |
4946 | static int perf_fasync(int fd, struct file *filp, int on) |
4947 | { | |
496ad9aa | 4948 | struct inode *inode = file_inode(filp); |
cdd6c482 | 4949 | struct perf_event *event = filp->private_data; |
3c446b3d PZ |
4950 | int retval; |
4951 | ||
5955102c | 4952 | inode_lock(inode); |
cdd6c482 | 4953 | retval = fasync_helper(fd, filp, on, &event->fasync); |
5955102c | 4954 | inode_unlock(inode); |
3c446b3d PZ |
4955 | |
4956 | if (retval < 0) | |
4957 | return retval; | |
4958 | ||
4959 | return 0; | |
4960 | } | |
4961 | ||
0793a61d | 4962 | static const struct file_operations perf_fops = { |
3326c1ce | 4963 | .llseek = no_llseek, |
0793a61d TG |
4964 | .release = perf_release, |
4965 | .read = perf_read, | |
4966 | .poll = perf_poll, | |
d859e29f | 4967 | .unlocked_ioctl = perf_ioctl, |
b3f20785 | 4968 | .compat_ioctl = perf_compat_ioctl, |
37d81828 | 4969 | .mmap = perf_mmap, |
3c446b3d | 4970 | .fasync = perf_fasync, |
0793a61d TG |
4971 | }; |
4972 | ||
925d519a | 4973 | /* |
cdd6c482 | 4974 | * Perf event wakeup |
925d519a PZ |
4975 | * |
4976 | * If there's data, ensure we set the poll() state and publish everything | |
4977 | * to user-space before waking everybody up. | |
4978 | */ | |
4979 | ||
fed66e2c PZ |
4980 | static inline struct fasync_struct **perf_event_fasync(struct perf_event *event) |
4981 | { | |
4982 | /* only the parent has fasync state */ | |
4983 | if (event->parent) | |
4984 | event = event->parent; | |
4985 | return &event->fasync; | |
4986 | } | |
4987 | ||
cdd6c482 | 4988 | void perf_event_wakeup(struct perf_event *event) |
925d519a | 4989 | { |
10c6db11 | 4990 | ring_buffer_wakeup(event); |
4c9e2542 | 4991 | |
cdd6c482 | 4992 | if (event->pending_kill) { |
fed66e2c | 4993 | kill_fasync(perf_event_fasync(event), SIGIO, event->pending_kill); |
cdd6c482 | 4994 | event->pending_kill = 0; |
4c9e2542 | 4995 | } |
925d519a PZ |
4996 | } |
4997 | ||
e360adbe | 4998 | static void perf_pending_event(struct irq_work *entry) |
79f14641 | 4999 | { |
cdd6c482 IM |
5000 | struct perf_event *event = container_of(entry, |
5001 | struct perf_event, pending); | |
d525211f PZ |
5002 | int rctx; |
5003 | ||
5004 | rctx = perf_swevent_get_recursion_context(); | |
5005 | /* | |
5006 | * If we 'fail' here, that's OK, it means recursion is already disabled | |
5007 | * and we won't recurse 'further'. | |
5008 | */ | |
79f14641 | 5009 | |
cdd6c482 IM |
5010 | if (event->pending_disable) { |
5011 | event->pending_disable = 0; | |
fae3fde6 | 5012 | perf_event_disable_local(event); |
79f14641 PZ |
5013 | } |
5014 | ||
cdd6c482 IM |
5015 | if (event->pending_wakeup) { |
5016 | event->pending_wakeup = 0; | |
5017 | perf_event_wakeup(event); | |
79f14641 | 5018 | } |
d525211f PZ |
5019 | |
5020 | if (rctx >= 0) | |
5021 | perf_swevent_put_recursion_context(rctx); | |
79f14641 PZ |
5022 | } |
5023 | ||
39447b38 ZY |
5024 | /* |
5025 | * We assume there is only KVM supporting the callbacks. | |
5026 | * Later on, we might change it to a list if there is | |
5027 | * another virtualization implementation supporting the callbacks. | |
5028 | */ | |
5029 | struct perf_guest_info_callbacks *perf_guest_cbs; | |
5030 | ||
5031 | int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
5032 | { | |
5033 | perf_guest_cbs = cbs; | |
5034 | return 0; | |
5035 | } | |
5036 | EXPORT_SYMBOL_GPL(perf_register_guest_info_callbacks); | |
5037 | ||
5038 | int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
5039 | { | |
5040 | perf_guest_cbs = NULL; | |
5041 | return 0; | |
5042 | } | |
5043 | EXPORT_SYMBOL_GPL(perf_unregister_guest_info_callbacks); | |
5044 | ||
4018994f JO |
5045 | static void |
5046 | perf_output_sample_regs(struct perf_output_handle *handle, | |
5047 | struct pt_regs *regs, u64 mask) | |
5048 | { | |
5049 | int bit; | |
5050 | ||
5051 | for_each_set_bit(bit, (const unsigned long *) &mask, | |
5052 | sizeof(mask) * BITS_PER_BYTE) { | |
5053 | u64 val; | |
5054 | ||
5055 | val = perf_reg_value(regs, bit); | |
5056 | perf_output_put(handle, val); | |
5057 | } | |
5058 | } | |
5059 | ||
60e2364e | 5060 | static void perf_sample_regs_user(struct perf_regs *regs_user, |
88a7c26a AL |
5061 | struct pt_regs *regs, |
5062 | struct pt_regs *regs_user_copy) | |
4018994f | 5063 | { |
88a7c26a AL |
5064 | if (user_mode(regs)) { |
5065 | regs_user->abi = perf_reg_abi(current); | |
2565711f | 5066 | regs_user->regs = regs; |
88a7c26a AL |
5067 | } else if (current->mm) { |
5068 | perf_get_regs_user(regs_user, regs, regs_user_copy); | |
2565711f PZ |
5069 | } else { |
5070 | regs_user->abi = PERF_SAMPLE_REGS_ABI_NONE; | |
5071 | regs_user->regs = NULL; | |
4018994f JO |
5072 | } |
5073 | } | |
5074 | ||
60e2364e SE |
5075 | static void perf_sample_regs_intr(struct perf_regs *regs_intr, |
5076 | struct pt_regs *regs) | |
5077 | { | |
5078 | regs_intr->regs = regs; | |
5079 | regs_intr->abi = perf_reg_abi(current); | |
5080 | } | |
5081 | ||
5082 | ||
c5ebcedb JO |
5083 | /* |
5084 | * Get remaining task size from user stack pointer. | |
5085 | * | |
5086 | * It'd be better to take stack vma map and limit this more | |
5087 | * precisly, but there's no way to get it safely under interrupt, | |
5088 | * so using TASK_SIZE as limit. | |
5089 | */ | |
5090 | static u64 perf_ustack_task_size(struct pt_regs *regs) | |
5091 | { | |
5092 | unsigned long addr = perf_user_stack_pointer(regs); | |
5093 | ||
5094 | if (!addr || addr >= TASK_SIZE) | |
5095 | return 0; | |
5096 | ||
5097 | return TASK_SIZE - addr; | |
5098 | } | |
5099 | ||
5100 | static u16 | |
5101 | perf_sample_ustack_size(u16 stack_size, u16 header_size, | |
5102 | struct pt_regs *regs) | |
5103 | { | |
5104 | u64 task_size; | |
5105 | ||
5106 | /* No regs, no stack pointer, no dump. */ | |
5107 | if (!regs) | |
5108 | return 0; | |
5109 | ||
5110 | /* | |
5111 | * Check if we fit in with the requested stack size into the: | |
5112 | * - TASK_SIZE | |
5113 | * If we don't, we limit the size to the TASK_SIZE. | |
5114 | * | |
5115 | * - remaining sample size | |
5116 | * If we don't, we customize the stack size to | |
5117 | * fit in to the remaining sample size. | |
5118 | */ | |
5119 | ||
5120 | task_size = min((u64) USHRT_MAX, perf_ustack_task_size(regs)); | |
5121 | stack_size = min(stack_size, (u16) task_size); | |
5122 | ||
5123 | /* Current header size plus static size and dynamic size. */ | |
5124 | header_size += 2 * sizeof(u64); | |
5125 | ||
5126 | /* Do we fit in with the current stack dump size? */ | |
5127 | if ((u16) (header_size + stack_size) < header_size) { | |
5128 | /* | |
5129 | * If we overflow the maximum size for the sample, | |
5130 | * we customize the stack dump size to fit in. | |
5131 | */ | |
5132 | stack_size = USHRT_MAX - header_size - sizeof(u64); | |
5133 | stack_size = round_up(stack_size, sizeof(u64)); | |
5134 | } | |
5135 | ||
5136 | return stack_size; | |
5137 | } | |
5138 | ||
5139 | static void | |
5140 | perf_output_sample_ustack(struct perf_output_handle *handle, u64 dump_size, | |
5141 | struct pt_regs *regs) | |
5142 | { | |
5143 | /* Case of a kernel thread, nothing to dump */ | |
5144 | if (!regs) { | |
5145 | u64 size = 0; | |
5146 | perf_output_put(handle, size); | |
5147 | } else { | |
5148 | unsigned long sp; | |
5149 | unsigned int rem; | |
5150 | u64 dyn_size; | |
5151 | ||
5152 | /* | |
5153 | * We dump: | |
5154 | * static size | |
5155 | * - the size requested by user or the best one we can fit | |
5156 | * in to the sample max size | |
5157 | * data | |
5158 | * - user stack dump data | |
5159 | * dynamic size | |
5160 | * - the actual dumped size | |
5161 | */ | |
5162 | ||
5163 | /* Static size. */ | |
5164 | perf_output_put(handle, dump_size); | |
5165 | ||
5166 | /* Data. */ | |
5167 | sp = perf_user_stack_pointer(regs); | |
5168 | rem = __output_copy_user(handle, (void *) sp, dump_size); | |
5169 | dyn_size = dump_size - rem; | |
5170 | ||
5171 | perf_output_skip(handle, rem); | |
5172 | ||
5173 | /* Dynamic size. */ | |
5174 | perf_output_put(handle, dyn_size); | |
5175 | } | |
5176 | } | |
5177 | ||
c980d109 ACM |
5178 | static void __perf_event_header__init_id(struct perf_event_header *header, |
5179 | struct perf_sample_data *data, | |
5180 | struct perf_event *event) | |
6844c09d ACM |
5181 | { |
5182 | u64 sample_type = event->attr.sample_type; | |
5183 | ||
5184 | data->type = sample_type; | |
5185 | header->size += event->id_header_size; | |
5186 | ||
5187 | if (sample_type & PERF_SAMPLE_TID) { | |
5188 | /* namespace issues */ | |
5189 | data->tid_entry.pid = perf_event_pid(event, current); | |
5190 | data->tid_entry.tid = perf_event_tid(event, current); | |
5191 | } | |
5192 | ||
5193 | if (sample_type & PERF_SAMPLE_TIME) | |
34f43927 | 5194 | data->time = perf_event_clock(event); |
6844c09d | 5195 | |
ff3d527c | 5196 | if (sample_type & (PERF_SAMPLE_ID | PERF_SAMPLE_IDENTIFIER)) |
6844c09d ACM |
5197 | data->id = primary_event_id(event); |
5198 | ||
5199 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
5200 | data->stream_id = event->id; | |
5201 | ||
5202 | if (sample_type & PERF_SAMPLE_CPU) { | |
5203 | data->cpu_entry.cpu = raw_smp_processor_id(); | |
5204 | data->cpu_entry.reserved = 0; | |
5205 | } | |
5206 | } | |
5207 | ||
76369139 FW |
5208 | void perf_event_header__init_id(struct perf_event_header *header, |
5209 | struct perf_sample_data *data, | |
5210 | struct perf_event *event) | |
c980d109 ACM |
5211 | { |
5212 | if (event->attr.sample_id_all) | |
5213 | __perf_event_header__init_id(header, data, event); | |
5214 | } | |
5215 | ||
5216 | static void __perf_event__output_id_sample(struct perf_output_handle *handle, | |
5217 | struct perf_sample_data *data) | |
5218 | { | |
5219 | u64 sample_type = data->type; | |
5220 | ||
5221 | if (sample_type & PERF_SAMPLE_TID) | |
5222 | perf_output_put(handle, data->tid_entry); | |
5223 | ||
5224 | if (sample_type & PERF_SAMPLE_TIME) | |
5225 | perf_output_put(handle, data->time); | |
5226 | ||
5227 | if (sample_type & PERF_SAMPLE_ID) | |
5228 | perf_output_put(handle, data->id); | |
5229 | ||
5230 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
5231 | perf_output_put(handle, data->stream_id); | |
5232 | ||
5233 | if (sample_type & PERF_SAMPLE_CPU) | |
5234 | perf_output_put(handle, data->cpu_entry); | |
ff3d527c AH |
5235 | |
5236 | if (sample_type & PERF_SAMPLE_IDENTIFIER) | |
5237 | perf_output_put(handle, data->id); | |
c980d109 ACM |
5238 | } |
5239 | ||
76369139 FW |
5240 | void perf_event__output_id_sample(struct perf_event *event, |
5241 | struct perf_output_handle *handle, | |
5242 | struct perf_sample_data *sample) | |
c980d109 ACM |
5243 | { |
5244 | if (event->attr.sample_id_all) | |
5245 | __perf_event__output_id_sample(handle, sample); | |
5246 | } | |
5247 | ||
3dab77fb | 5248 | static void perf_output_read_one(struct perf_output_handle *handle, |
eed01528 SE |
5249 | struct perf_event *event, |
5250 | u64 enabled, u64 running) | |
3dab77fb | 5251 | { |
cdd6c482 | 5252 | u64 read_format = event->attr.read_format; |
3dab77fb PZ |
5253 | u64 values[4]; |
5254 | int n = 0; | |
5255 | ||
b5e58793 | 5256 | values[n++] = perf_event_count(event); |
3dab77fb | 5257 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { |
eed01528 | 5258 | values[n++] = enabled + |
cdd6c482 | 5259 | atomic64_read(&event->child_total_time_enabled); |
3dab77fb PZ |
5260 | } |
5261 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { | |
eed01528 | 5262 | values[n++] = running + |
cdd6c482 | 5263 | atomic64_read(&event->child_total_time_running); |
3dab77fb PZ |
5264 | } |
5265 | if (read_format & PERF_FORMAT_ID) | |
cdd6c482 | 5266 | values[n++] = primary_event_id(event); |
3dab77fb | 5267 | |
76369139 | 5268 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
5269 | } |
5270 | ||
5271 | /* | |
cdd6c482 | 5272 | * XXX PERF_FORMAT_GROUP vs inherited events seems difficult. |
3dab77fb PZ |
5273 | */ |
5274 | static void perf_output_read_group(struct perf_output_handle *handle, | |
eed01528 SE |
5275 | struct perf_event *event, |
5276 | u64 enabled, u64 running) | |
3dab77fb | 5277 | { |
cdd6c482 IM |
5278 | struct perf_event *leader = event->group_leader, *sub; |
5279 | u64 read_format = event->attr.read_format; | |
3dab77fb PZ |
5280 | u64 values[5]; |
5281 | int n = 0; | |
5282 | ||
5283 | values[n++] = 1 + leader->nr_siblings; | |
5284 | ||
5285 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
eed01528 | 5286 | values[n++] = enabled; |
3dab77fb PZ |
5287 | |
5288 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
eed01528 | 5289 | values[n++] = running; |
3dab77fb | 5290 | |
cdd6c482 | 5291 | if (leader != event) |
3dab77fb PZ |
5292 | leader->pmu->read(leader); |
5293 | ||
b5e58793 | 5294 | values[n++] = perf_event_count(leader); |
3dab77fb | 5295 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 5296 | values[n++] = primary_event_id(leader); |
3dab77fb | 5297 | |
76369139 | 5298 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb | 5299 | |
65abc865 | 5300 | list_for_each_entry(sub, &leader->sibling_list, group_entry) { |
3dab77fb PZ |
5301 | n = 0; |
5302 | ||
6f5ab001 JO |
5303 | if ((sub != event) && |
5304 | (sub->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
5305 | sub->pmu->read(sub); |
5306 | ||
b5e58793 | 5307 | values[n++] = perf_event_count(sub); |
3dab77fb | 5308 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 5309 | values[n++] = primary_event_id(sub); |
3dab77fb | 5310 | |
76369139 | 5311 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
5312 | } |
5313 | } | |
5314 | ||
eed01528 SE |
5315 | #define PERF_FORMAT_TOTAL_TIMES (PERF_FORMAT_TOTAL_TIME_ENABLED|\ |
5316 | PERF_FORMAT_TOTAL_TIME_RUNNING) | |
5317 | ||
3dab77fb | 5318 | static void perf_output_read(struct perf_output_handle *handle, |
cdd6c482 | 5319 | struct perf_event *event) |
3dab77fb | 5320 | { |
e3f3541c | 5321 | u64 enabled = 0, running = 0, now; |
eed01528 SE |
5322 | u64 read_format = event->attr.read_format; |
5323 | ||
5324 | /* | |
5325 | * compute total_time_enabled, total_time_running | |
5326 | * based on snapshot values taken when the event | |
5327 | * was last scheduled in. | |
5328 | * | |
5329 | * we cannot simply called update_context_time() | |
5330 | * because of locking issue as we are called in | |
5331 | * NMI context | |
5332 | */ | |
c4794295 | 5333 | if (read_format & PERF_FORMAT_TOTAL_TIMES) |
e3f3541c | 5334 | calc_timer_values(event, &now, &enabled, &running); |
eed01528 | 5335 | |
cdd6c482 | 5336 | if (event->attr.read_format & PERF_FORMAT_GROUP) |
eed01528 | 5337 | perf_output_read_group(handle, event, enabled, running); |
3dab77fb | 5338 | else |
eed01528 | 5339 | perf_output_read_one(handle, event, enabled, running); |
3dab77fb PZ |
5340 | } |
5341 | ||
5622f295 MM |
5342 | void perf_output_sample(struct perf_output_handle *handle, |
5343 | struct perf_event_header *header, | |
5344 | struct perf_sample_data *data, | |
cdd6c482 | 5345 | struct perf_event *event) |
5622f295 MM |
5346 | { |
5347 | u64 sample_type = data->type; | |
5348 | ||
5349 | perf_output_put(handle, *header); | |
5350 | ||
ff3d527c AH |
5351 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
5352 | perf_output_put(handle, data->id); | |
5353 | ||
5622f295 MM |
5354 | if (sample_type & PERF_SAMPLE_IP) |
5355 | perf_output_put(handle, data->ip); | |
5356 | ||
5357 | if (sample_type & PERF_SAMPLE_TID) | |
5358 | perf_output_put(handle, data->tid_entry); | |
5359 | ||
5360 | if (sample_type & PERF_SAMPLE_TIME) | |
5361 | perf_output_put(handle, data->time); | |
5362 | ||
5363 | if (sample_type & PERF_SAMPLE_ADDR) | |
5364 | perf_output_put(handle, data->addr); | |
5365 | ||
5366 | if (sample_type & PERF_SAMPLE_ID) | |
5367 | perf_output_put(handle, data->id); | |
5368 | ||
5369 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
5370 | perf_output_put(handle, data->stream_id); | |
5371 | ||
5372 | if (sample_type & PERF_SAMPLE_CPU) | |
5373 | perf_output_put(handle, data->cpu_entry); | |
5374 | ||
5375 | if (sample_type & PERF_SAMPLE_PERIOD) | |
5376 | perf_output_put(handle, data->period); | |
5377 | ||
5378 | if (sample_type & PERF_SAMPLE_READ) | |
cdd6c482 | 5379 | perf_output_read(handle, event); |
5622f295 MM |
5380 | |
5381 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { | |
5382 | if (data->callchain) { | |
5383 | int size = 1; | |
5384 | ||
5385 | if (data->callchain) | |
5386 | size += data->callchain->nr; | |
5387 | ||
5388 | size *= sizeof(u64); | |
5389 | ||
76369139 | 5390 | __output_copy(handle, data->callchain, size); |
5622f295 MM |
5391 | } else { |
5392 | u64 nr = 0; | |
5393 | perf_output_put(handle, nr); | |
5394 | } | |
5395 | } | |
5396 | ||
5397 | if (sample_type & PERF_SAMPLE_RAW) { | |
5398 | if (data->raw) { | |
fa128e6a AS |
5399 | u32 raw_size = data->raw->size; |
5400 | u32 real_size = round_up(raw_size + sizeof(u32), | |
5401 | sizeof(u64)) - sizeof(u32); | |
5402 | u64 zero = 0; | |
5403 | ||
5404 | perf_output_put(handle, real_size); | |
5405 | __output_copy(handle, data->raw->data, raw_size); | |
5406 | if (real_size - raw_size) | |
5407 | __output_copy(handle, &zero, real_size - raw_size); | |
5622f295 MM |
5408 | } else { |
5409 | struct { | |
5410 | u32 size; | |
5411 | u32 data; | |
5412 | } raw = { | |
5413 | .size = sizeof(u32), | |
5414 | .data = 0, | |
5415 | }; | |
5416 | perf_output_put(handle, raw); | |
5417 | } | |
5418 | } | |
a7ac67ea | 5419 | |
bce38cd5 SE |
5420 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { |
5421 | if (data->br_stack) { | |
5422 | size_t size; | |
5423 | ||
5424 | size = data->br_stack->nr | |
5425 | * sizeof(struct perf_branch_entry); | |
5426 | ||
5427 | perf_output_put(handle, data->br_stack->nr); | |
5428 | perf_output_copy(handle, data->br_stack->entries, size); | |
5429 | } else { | |
5430 | /* | |
5431 | * we always store at least the value of nr | |
5432 | */ | |
5433 | u64 nr = 0; | |
5434 | perf_output_put(handle, nr); | |
5435 | } | |
5436 | } | |
4018994f JO |
5437 | |
5438 | if (sample_type & PERF_SAMPLE_REGS_USER) { | |
5439 | u64 abi = data->regs_user.abi; | |
5440 | ||
5441 | /* | |
5442 | * If there are no regs to dump, notice it through | |
5443 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
5444 | */ | |
5445 | perf_output_put(handle, abi); | |
5446 | ||
5447 | if (abi) { | |
5448 | u64 mask = event->attr.sample_regs_user; | |
5449 | perf_output_sample_regs(handle, | |
5450 | data->regs_user.regs, | |
5451 | mask); | |
5452 | } | |
5453 | } | |
c5ebcedb | 5454 | |
a5cdd40c | 5455 | if (sample_type & PERF_SAMPLE_STACK_USER) { |
c5ebcedb JO |
5456 | perf_output_sample_ustack(handle, |
5457 | data->stack_user_size, | |
5458 | data->regs_user.regs); | |
a5cdd40c | 5459 | } |
c3feedf2 AK |
5460 | |
5461 | if (sample_type & PERF_SAMPLE_WEIGHT) | |
5462 | perf_output_put(handle, data->weight); | |
d6be9ad6 SE |
5463 | |
5464 | if (sample_type & PERF_SAMPLE_DATA_SRC) | |
5465 | perf_output_put(handle, data->data_src.val); | |
a5cdd40c | 5466 | |
fdfbbd07 AK |
5467 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
5468 | perf_output_put(handle, data->txn); | |
5469 | ||
60e2364e SE |
5470 | if (sample_type & PERF_SAMPLE_REGS_INTR) { |
5471 | u64 abi = data->regs_intr.abi; | |
5472 | /* | |
5473 | * If there are no regs to dump, notice it through | |
5474 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
5475 | */ | |
5476 | perf_output_put(handle, abi); | |
5477 | ||
5478 | if (abi) { | |
5479 | u64 mask = event->attr.sample_regs_intr; | |
5480 | ||
5481 | perf_output_sample_regs(handle, | |
5482 | data->regs_intr.regs, | |
5483 | mask); | |
5484 | } | |
5485 | } | |
5486 | ||
a5cdd40c PZ |
5487 | if (!event->attr.watermark) { |
5488 | int wakeup_events = event->attr.wakeup_events; | |
5489 | ||
5490 | if (wakeup_events) { | |
5491 | struct ring_buffer *rb = handle->rb; | |
5492 | int events = local_inc_return(&rb->events); | |
5493 | ||
5494 | if (events >= wakeup_events) { | |
5495 | local_sub(wakeup_events, &rb->events); | |
5496 | local_inc(&rb->wakeup); | |
5497 | } | |
5498 | } | |
5499 | } | |
5622f295 MM |
5500 | } |
5501 | ||
5502 | void perf_prepare_sample(struct perf_event_header *header, | |
5503 | struct perf_sample_data *data, | |
cdd6c482 | 5504 | struct perf_event *event, |
5622f295 | 5505 | struct pt_regs *regs) |
7b732a75 | 5506 | { |
cdd6c482 | 5507 | u64 sample_type = event->attr.sample_type; |
7b732a75 | 5508 | |
cdd6c482 | 5509 | header->type = PERF_RECORD_SAMPLE; |
c320c7b7 | 5510 | header->size = sizeof(*header) + event->header_size; |
5622f295 MM |
5511 | |
5512 | header->misc = 0; | |
5513 | header->misc |= perf_misc_flags(regs); | |
6fab0192 | 5514 | |
c980d109 | 5515 | __perf_event_header__init_id(header, data, event); |
6844c09d | 5516 | |
c320c7b7 | 5517 | if (sample_type & PERF_SAMPLE_IP) |
5622f295 MM |
5518 | data->ip = perf_instruction_pointer(regs); |
5519 | ||
b23f3325 | 5520 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { |
5622f295 | 5521 | int size = 1; |
394ee076 | 5522 | |
e6dab5ff | 5523 | data->callchain = perf_callchain(event, regs); |
5622f295 MM |
5524 | |
5525 | if (data->callchain) | |
5526 | size += data->callchain->nr; | |
5527 | ||
5528 | header->size += size * sizeof(u64); | |
394ee076 PZ |
5529 | } |
5530 | ||
3a43ce68 | 5531 | if (sample_type & PERF_SAMPLE_RAW) { |
a044560c PZ |
5532 | int size = sizeof(u32); |
5533 | ||
5534 | if (data->raw) | |
5535 | size += data->raw->size; | |
5536 | else | |
5537 | size += sizeof(u32); | |
5538 | ||
fa128e6a | 5539 | header->size += round_up(size, sizeof(u64)); |
7f453c24 | 5540 | } |
bce38cd5 SE |
5541 | |
5542 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { | |
5543 | int size = sizeof(u64); /* nr */ | |
5544 | if (data->br_stack) { | |
5545 | size += data->br_stack->nr | |
5546 | * sizeof(struct perf_branch_entry); | |
5547 | } | |
5548 | header->size += size; | |
5549 | } | |
4018994f | 5550 | |
2565711f | 5551 | if (sample_type & (PERF_SAMPLE_REGS_USER | PERF_SAMPLE_STACK_USER)) |
88a7c26a AL |
5552 | perf_sample_regs_user(&data->regs_user, regs, |
5553 | &data->regs_user_copy); | |
2565711f | 5554 | |
4018994f JO |
5555 | if (sample_type & PERF_SAMPLE_REGS_USER) { |
5556 | /* regs dump ABI info */ | |
5557 | int size = sizeof(u64); | |
5558 | ||
4018994f JO |
5559 | if (data->regs_user.regs) { |
5560 | u64 mask = event->attr.sample_regs_user; | |
5561 | size += hweight64(mask) * sizeof(u64); | |
5562 | } | |
5563 | ||
5564 | header->size += size; | |
5565 | } | |
c5ebcedb JO |
5566 | |
5567 | if (sample_type & PERF_SAMPLE_STACK_USER) { | |
5568 | /* | |
5569 | * Either we need PERF_SAMPLE_STACK_USER bit to be allways | |
5570 | * processed as the last one or have additional check added | |
5571 | * in case new sample type is added, because we could eat | |
5572 | * up the rest of the sample size. | |
5573 | */ | |
c5ebcedb JO |
5574 | u16 stack_size = event->attr.sample_stack_user; |
5575 | u16 size = sizeof(u64); | |
5576 | ||
c5ebcedb | 5577 | stack_size = perf_sample_ustack_size(stack_size, header->size, |
2565711f | 5578 | data->regs_user.regs); |
c5ebcedb JO |
5579 | |
5580 | /* | |
5581 | * If there is something to dump, add space for the dump | |
5582 | * itself and for the field that tells the dynamic size, | |
5583 | * which is how many have been actually dumped. | |
5584 | */ | |
5585 | if (stack_size) | |
5586 | size += sizeof(u64) + stack_size; | |
5587 | ||
5588 | data->stack_user_size = stack_size; | |
5589 | header->size += size; | |
5590 | } | |
60e2364e SE |
5591 | |
5592 | if (sample_type & PERF_SAMPLE_REGS_INTR) { | |
5593 | /* regs dump ABI info */ | |
5594 | int size = sizeof(u64); | |
5595 | ||
5596 | perf_sample_regs_intr(&data->regs_intr, regs); | |
5597 | ||
5598 | if (data->regs_intr.regs) { | |
5599 | u64 mask = event->attr.sample_regs_intr; | |
5600 | ||
5601 | size += hweight64(mask) * sizeof(u64); | |
5602 | } | |
5603 | ||
5604 | header->size += size; | |
5605 | } | |
5622f295 | 5606 | } |
7f453c24 | 5607 | |
21509084 YZ |
5608 | void perf_event_output(struct perf_event *event, |
5609 | struct perf_sample_data *data, | |
5610 | struct pt_regs *regs) | |
5622f295 MM |
5611 | { |
5612 | struct perf_output_handle handle; | |
5613 | struct perf_event_header header; | |
689802b2 | 5614 | |
927c7a9e FW |
5615 | /* protect the callchain buffers */ |
5616 | rcu_read_lock(); | |
5617 | ||
cdd6c482 | 5618 | perf_prepare_sample(&header, data, event, regs); |
5c148194 | 5619 | |
a7ac67ea | 5620 | if (perf_output_begin(&handle, event, header.size)) |
927c7a9e | 5621 | goto exit; |
0322cd6e | 5622 | |
cdd6c482 | 5623 | perf_output_sample(&handle, &header, data, event); |
f413cdb8 | 5624 | |
8a057d84 | 5625 | perf_output_end(&handle); |
927c7a9e FW |
5626 | |
5627 | exit: | |
5628 | rcu_read_unlock(); | |
0322cd6e PZ |
5629 | } |
5630 | ||
38b200d6 | 5631 | /* |
cdd6c482 | 5632 | * read event_id |
38b200d6 PZ |
5633 | */ |
5634 | ||
5635 | struct perf_read_event { | |
5636 | struct perf_event_header header; | |
5637 | ||
5638 | u32 pid; | |
5639 | u32 tid; | |
38b200d6 PZ |
5640 | }; |
5641 | ||
5642 | static void | |
cdd6c482 | 5643 | perf_event_read_event(struct perf_event *event, |
38b200d6 PZ |
5644 | struct task_struct *task) |
5645 | { | |
5646 | struct perf_output_handle handle; | |
c980d109 | 5647 | struct perf_sample_data sample; |
dfc65094 | 5648 | struct perf_read_event read_event = { |
38b200d6 | 5649 | .header = { |
cdd6c482 | 5650 | .type = PERF_RECORD_READ, |
38b200d6 | 5651 | .misc = 0, |
c320c7b7 | 5652 | .size = sizeof(read_event) + event->read_size, |
38b200d6 | 5653 | }, |
cdd6c482 IM |
5654 | .pid = perf_event_pid(event, task), |
5655 | .tid = perf_event_tid(event, task), | |
38b200d6 | 5656 | }; |
3dab77fb | 5657 | int ret; |
38b200d6 | 5658 | |
c980d109 | 5659 | perf_event_header__init_id(&read_event.header, &sample, event); |
a7ac67ea | 5660 | ret = perf_output_begin(&handle, event, read_event.header.size); |
38b200d6 PZ |
5661 | if (ret) |
5662 | return; | |
5663 | ||
dfc65094 | 5664 | perf_output_put(&handle, read_event); |
cdd6c482 | 5665 | perf_output_read(&handle, event); |
c980d109 | 5666 | perf_event__output_id_sample(event, &handle, &sample); |
3dab77fb | 5667 | |
38b200d6 PZ |
5668 | perf_output_end(&handle); |
5669 | } | |
5670 | ||
52d857a8 JO |
5671 | typedef void (perf_event_aux_output_cb)(struct perf_event *event, void *data); |
5672 | ||
5673 | static void | |
5674 | perf_event_aux_ctx(struct perf_event_context *ctx, | |
52d857a8 JO |
5675 | perf_event_aux_output_cb output, |
5676 | void *data) | |
5677 | { | |
5678 | struct perf_event *event; | |
5679 | ||
5680 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
5681 | if (event->state < PERF_EVENT_STATE_INACTIVE) | |
5682 | continue; | |
5683 | if (!event_filter_match(event)) | |
5684 | continue; | |
67516844 | 5685 | output(event, data); |
52d857a8 JO |
5686 | } |
5687 | } | |
5688 | ||
4e93ad60 JO |
5689 | static void |
5690 | perf_event_aux_task_ctx(perf_event_aux_output_cb output, void *data, | |
5691 | struct perf_event_context *task_ctx) | |
5692 | { | |
5693 | rcu_read_lock(); | |
5694 | preempt_disable(); | |
5695 | perf_event_aux_ctx(task_ctx, output, data); | |
5696 | preempt_enable(); | |
5697 | rcu_read_unlock(); | |
5698 | } | |
5699 | ||
52d857a8 | 5700 | static void |
67516844 | 5701 | perf_event_aux(perf_event_aux_output_cb output, void *data, |
52d857a8 JO |
5702 | struct perf_event_context *task_ctx) |
5703 | { | |
5704 | struct perf_cpu_context *cpuctx; | |
5705 | struct perf_event_context *ctx; | |
5706 | struct pmu *pmu; | |
5707 | int ctxn; | |
5708 | ||
4e93ad60 JO |
5709 | /* |
5710 | * If we have task_ctx != NULL we only notify | |
5711 | * the task context itself. The task_ctx is set | |
5712 | * only for EXIT events before releasing task | |
5713 | * context. | |
5714 | */ | |
5715 | if (task_ctx) { | |
5716 | perf_event_aux_task_ctx(output, data, task_ctx); | |
5717 | return; | |
5718 | } | |
5719 | ||
52d857a8 JO |
5720 | rcu_read_lock(); |
5721 | list_for_each_entry_rcu(pmu, &pmus, entry) { | |
5722 | cpuctx = get_cpu_ptr(pmu->pmu_cpu_context); | |
5723 | if (cpuctx->unique_pmu != pmu) | |
5724 | goto next; | |
67516844 | 5725 | perf_event_aux_ctx(&cpuctx->ctx, output, data); |
52d857a8 JO |
5726 | ctxn = pmu->task_ctx_nr; |
5727 | if (ctxn < 0) | |
5728 | goto next; | |
5729 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); | |
5730 | if (ctx) | |
67516844 | 5731 | perf_event_aux_ctx(ctx, output, data); |
52d857a8 JO |
5732 | next: |
5733 | put_cpu_ptr(pmu->pmu_cpu_context); | |
5734 | } | |
52d857a8 JO |
5735 | rcu_read_unlock(); |
5736 | } | |
5737 | ||
60313ebe | 5738 | /* |
9f498cc5 PZ |
5739 | * task tracking -- fork/exit |
5740 | * | |
13d7a241 | 5741 | * enabled by: attr.comm | attr.mmap | attr.mmap2 | attr.mmap_data | attr.task |
60313ebe PZ |
5742 | */ |
5743 | ||
9f498cc5 | 5744 | struct perf_task_event { |
3a80b4a3 | 5745 | struct task_struct *task; |
cdd6c482 | 5746 | struct perf_event_context *task_ctx; |
60313ebe PZ |
5747 | |
5748 | struct { | |
5749 | struct perf_event_header header; | |
5750 | ||
5751 | u32 pid; | |
5752 | u32 ppid; | |
9f498cc5 PZ |
5753 | u32 tid; |
5754 | u32 ptid; | |
393b2ad8 | 5755 | u64 time; |
cdd6c482 | 5756 | } event_id; |
60313ebe PZ |
5757 | }; |
5758 | ||
67516844 JO |
5759 | static int perf_event_task_match(struct perf_event *event) |
5760 | { | |
13d7a241 SE |
5761 | return event->attr.comm || event->attr.mmap || |
5762 | event->attr.mmap2 || event->attr.mmap_data || | |
5763 | event->attr.task; | |
67516844 JO |
5764 | } |
5765 | ||
cdd6c482 | 5766 | static void perf_event_task_output(struct perf_event *event, |
52d857a8 | 5767 | void *data) |
60313ebe | 5768 | { |
52d857a8 | 5769 | struct perf_task_event *task_event = data; |
60313ebe | 5770 | struct perf_output_handle handle; |
c980d109 | 5771 | struct perf_sample_data sample; |
9f498cc5 | 5772 | struct task_struct *task = task_event->task; |
c980d109 | 5773 | int ret, size = task_event->event_id.header.size; |
8bb39f9a | 5774 | |
67516844 JO |
5775 | if (!perf_event_task_match(event)) |
5776 | return; | |
5777 | ||
c980d109 | 5778 | perf_event_header__init_id(&task_event->event_id.header, &sample, event); |
60313ebe | 5779 | |
c980d109 | 5780 | ret = perf_output_begin(&handle, event, |
a7ac67ea | 5781 | task_event->event_id.header.size); |
ef60777c | 5782 | if (ret) |
c980d109 | 5783 | goto out; |
60313ebe | 5784 | |
cdd6c482 IM |
5785 | task_event->event_id.pid = perf_event_pid(event, task); |
5786 | task_event->event_id.ppid = perf_event_pid(event, current); | |
60313ebe | 5787 | |
cdd6c482 IM |
5788 | task_event->event_id.tid = perf_event_tid(event, task); |
5789 | task_event->event_id.ptid = perf_event_tid(event, current); | |
9f498cc5 | 5790 | |
34f43927 PZ |
5791 | task_event->event_id.time = perf_event_clock(event); |
5792 | ||
cdd6c482 | 5793 | perf_output_put(&handle, task_event->event_id); |
393b2ad8 | 5794 | |
c980d109 ACM |
5795 | perf_event__output_id_sample(event, &handle, &sample); |
5796 | ||
60313ebe | 5797 | perf_output_end(&handle); |
c980d109 ACM |
5798 | out: |
5799 | task_event->event_id.header.size = size; | |
60313ebe PZ |
5800 | } |
5801 | ||
cdd6c482 IM |
5802 | static void perf_event_task(struct task_struct *task, |
5803 | struct perf_event_context *task_ctx, | |
3a80b4a3 | 5804 | int new) |
60313ebe | 5805 | { |
9f498cc5 | 5806 | struct perf_task_event task_event; |
60313ebe | 5807 | |
cdd6c482 IM |
5808 | if (!atomic_read(&nr_comm_events) && |
5809 | !atomic_read(&nr_mmap_events) && | |
5810 | !atomic_read(&nr_task_events)) | |
60313ebe PZ |
5811 | return; |
5812 | ||
9f498cc5 | 5813 | task_event = (struct perf_task_event){ |
3a80b4a3 PZ |
5814 | .task = task, |
5815 | .task_ctx = task_ctx, | |
cdd6c482 | 5816 | .event_id = { |
60313ebe | 5817 | .header = { |
cdd6c482 | 5818 | .type = new ? PERF_RECORD_FORK : PERF_RECORD_EXIT, |
573402db | 5819 | .misc = 0, |
cdd6c482 | 5820 | .size = sizeof(task_event.event_id), |
60313ebe | 5821 | }, |
573402db PZ |
5822 | /* .pid */ |
5823 | /* .ppid */ | |
9f498cc5 PZ |
5824 | /* .tid */ |
5825 | /* .ptid */ | |
34f43927 | 5826 | /* .time */ |
60313ebe PZ |
5827 | }, |
5828 | }; | |
5829 | ||
67516844 | 5830 | perf_event_aux(perf_event_task_output, |
52d857a8 JO |
5831 | &task_event, |
5832 | task_ctx); | |
9f498cc5 PZ |
5833 | } |
5834 | ||
cdd6c482 | 5835 | void perf_event_fork(struct task_struct *task) |
9f498cc5 | 5836 | { |
cdd6c482 | 5837 | perf_event_task(task, NULL, 1); |
60313ebe PZ |
5838 | } |
5839 | ||
8d1b2d93 PZ |
5840 | /* |
5841 | * comm tracking | |
5842 | */ | |
5843 | ||
5844 | struct perf_comm_event { | |
22a4f650 IM |
5845 | struct task_struct *task; |
5846 | char *comm; | |
8d1b2d93 PZ |
5847 | int comm_size; |
5848 | ||
5849 | struct { | |
5850 | struct perf_event_header header; | |
5851 | ||
5852 | u32 pid; | |
5853 | u32 tid; | |
cdd6c482 | 5854 | } event_id; |
8d1b2d93 PZ |
5855 | }; |
5856 | ||
67516844 JO |
5857 | static int perf_event_comm_match(struct perf_event *event) |
5858 | { | |
5859 | return event->attr.comm; | |
5860 | } | |
5861 | ||
cdd6c482 | 5862 | static void perf_event_comm_output(struct perf_event *event, |
52d857a8 | 5863 | void *data) |
8d1b2d93 | 5864 | { |
52d857a8 | 5865 | struct perf_comm_event *comm_event = data; |
8d1b2d93 | 5866 | struct perf_output_handle handle; |
c980d109 | 5867 | struct perf_sample_data sample; |
cdd6c482 | 5868 | int size = comm_event->event_id.header.size; |
c980d109 ACM |
5869 | int ret; |
5870 | ||
67516844 JO |
5871 | if (!perf_event_comm_match(event)) |
5872 | return; | |
5873 | ||
c980d109 ACM |
5874 | perf_event_header__init_id(&comm_event->event_id.header, &sample, event); |
5875 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 5876 | comm_event->event_id.header.size); |
8d1b2d93 PZ |
5877 | |
5878 | if (ret) | |
c980d109 | 5879 | goto out; |
8d1b2d93 | 5880 | |
cdd6c482 IM |
5881 | comm_event->event_id.pid = perf_event_pid(event, comm_event->task); |
5882 | comm_event->event_id.tid = perf_event_tid(event, comm_event->task); | |
709e50cf | 5883 | |
cdd6c482 | 5884 | perf_output_put(&handle, comm_event->event_id); |
76369139 | 5885 | __output_copy(&handle, comm_event->comm, |
8d1b2d93 | 5886 | comm_event->comm_size); |
c980d109 ACM |
5887 | |
5888 | perf_event__output_id_sample(event, &handle, &sample); | |
5889 | ||
8d1b2d93 | 5890 | perf_output_end(&handle); |
c980d109 ACM |
5891 | out: |
5892 | comm_event->event_id.header.size = size; | |
8d1b2d93 PZ |
5893 | } |
5894 | ||
cdd6c482 | 5895 | static void perf_event_comm_event(struct perf_comm_event *comm_event) |
8d1b2d93 | 5896 | { |
413ee3b4 | 5897 | char comm[TASK_COMM_LEN]; |
8d1b2d93 | 5898 | unsigned int size; |
8d1b2d93 | 5899 | |
413ee3b4 | 5900 | memset(comm, 0, sizeof(comm)); |
96b02d78 | 5901 | strlcpy(comm, comm_event->task->comm, sizeof(comm)); |
888fcee0 | 5902 | size = ALIGN(strlen(comm)+1, sizeof(u64)); |
8d1b2d93 PZ |
5903 | |
5904 | comm_event->comm = comm; | |
5905 | comm_event->comm_size = size; | |
5906 | ||
cdd6c482 | 5907 | comm_event->event_id.header.size = sizeof(comm_event->event_id) + size; |
8dc85d54 | 5908 | |
67516844 | 5909 | perf_event_aux(perf_event_comm_output, |
52d857a8 JO |
5910 | comm_event, |
5911 | NULL); | |
8d1b2d93 PZ |
5912 | } |
5913 | ||
82b89778 | 5914 | void perf_event_comm(struct task_struct *task, bool exec) |
8d1b2d93 | 5915 | { |
9ee318a7 PZ |
5916 | struct perf_comm_event comm_event; |
5917 | ||
cdd6c482 | 5918 | if (!atomic_read(&nr_comm_events)) |
9ee318a7 | 5919 | return; |
a63eaf34 | 5920 | |
9ee318a7 | 5921 | comm_event = (struct perf_comm_event){ |
8d1b2d93 | 5922 | .task = task, |
573402db PZ |
5923 | /* .comm */ |
5924 | /* .comm_size */ | |
cdd6c482 | 5925 | .event_id = { |
573402db | 5926 | .header = { |
cdd6c482 | 5927 | .type = PERF_RECORD_COMM, |
82b89778 | 5928 | .misc = exec ? PERF_RECORD_MISC_COMM_EXEC : 0, |
573402db PZ |
5929 | /* .size */ |
5930 | }, | |
5931 | /* .pid */ | |
5932 | /* .tid */ | |
8d1b2d93 PZ |
5933 | }, |
5934 | }; | |
5935 | ||
cdd6c482 | 5936 | perf_event_comm_event(&comm_event); |
8d1b2d93 PZ |
5937 | } |
5938 | ||
0a4a9391 PZ |
5939 | /* |
5940 | * mmap tracking | |
5941 | */ | |
5942 | ||
5943 | struct perf_mmap_event { | |
089dd79d PZ |
5944 | struct vm_area_struct *vma; |
5945 | ||
5946 | const char *file_name; | |
5947 | int file_size; | |
13d7a241 SE |
5948 | int maj, min; |
5949 | u64 ino; | |
5950 | u64 ino_generation; | |
f972eb63 | 5951 | u32 prot, flags; |
0a4a9391 PZ |
5952 | |
5953 | struct { | |
5954 | struct perf_event_header header; | |
5955 | ||
5956 | u32 pid; | |
5957 | u32 tid; | |
5958 | u64 start; | |
5959 | u64 len; | |
5960 | u64 pgoff; | |
cdd6c482 | 5961 | } event_id; |
0a4a9391 PZ |
5962 | }; |
5963 | ||
67516844 JO |
5964 | static int perf_event_mmap_match(struct perf_event *event, |
5965 | void *data) | |
5966 | { | |
5967 | struct perf_mmap_event *mmap_event = data; | |
5968 | struct vm_area_struct *vma = mmap_event->vma; | |
5969 | int executable = vma->vm_flags & VM_EXEC; | |
5970 | ||
5971 | return (!executable && event->attr.mmap_data) || | |
13d7a241 | 5972 | (executable && (event->attr.mmap || event->attr.mmap2)); |
67516844 JO |
5973 | } |
5974 | ||
cdd6c482 | 5975 | static void perf_event_mmap_output(struct perf_event *event, |
52d857a8 | 5976 | void *data) |
0a4a9391 | 5977 | { |
52d857a8 | 5978 | struct perf_mmap_event *mmap_event = data; |
0a4a9391 | 5979 | struct perf_output_handle handle; |
c980d109 | 5980 | struct perf_sample_data sample; |
cdd6c482 | 5981 | int size = mmap_event->event_id.header.size; |
c980d109 | 5982 | int ret; |
0a4a9391 | 5983 | |
67516844 JO |
5984 | if (!perf_event_mmap_match(event, data)) |
5985 | return; | |
5986 | ||
13d7a241 SE |
5987 | if (event->attr.mmap2) { |
5988 | mmap_event->event_id.header.type = PERF_RECORD_MMAP2; | |
5989 | mmap_event->event_id.header.size += sizeof(mmap_event->maj); | |
5990 | mmap_event->event_id.header.size += sizeof(mmap_event->min); | |
5991 | mmap_event->event_id.header.size += sizeof(mmap_event->ino); | |
d008d525 | 5992 | mmap_event->event_id.header.size += sizeof(mmap_event->ino_generation); |
f972eb63 PZ |
5993 | mmap_event->event_id.header.size += sizeof(mmap_event->prot); |
5994 | mmap_event->event_id.header.size += sizeof(mmap_event->flags); | |
13d7a241 SE |
5995 | } |
5996 | ||
c980d109 ACM |
5997 | perf_event_header__init_id(&mmap_event->event_id.header, &sample, event); |
5998 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 5999 | mmap_event->event_id.header.size); |
0a4a9391 | 6000 | if (ret) |
c980d109 | 6001 | goto out; |
0a4a9391 | 6002 | |
cdd6c482 IM |
6003 | mmap_event->event_id.pid = perf_event_pid(event, current); |
6004 | mmap_event->event_id.tid = perf_event_tid(event, current); | |
709e50cf | 6005 | |
cdd6c482 | 6006 | perf_output_put(&handle, mmap_event->event_id); |
13d7a241 SE |
6007 | |
6008 | if (event->attr.mmap2) { | |
6009 | perf_output_put(&handle, mmap_event->maj); | |
6010 | perf_output_put(&handle, mmap_event->min); | |
6011 | perf_output_put(&handle, mmap_event->ino); | |
6012 | perf_output_put(&handle, mmap_event->ino_generation); | |
f972eb63 PZ |
6013 | perf_output_put(&handle, mmap_event->prot); |
6014 | perf_output_put(&handle, mmap_event->flags); | |
13d7a241 SE |
6015 | } |
6016 | ||
76369139 | 6017 | __output_copy(&handle, mmap_event->file_name, |
0a4a9391 | 6018 | mmap_event->file_size); |
c980d109 ACM |
6019 | |
6020 | perf_event__output_id_sample(event, &handle, &sample); | |
6021 | ||
78d613eb | 6022 | perf_output_end(&handle); |
c980d109 ACM |
6023 | out: |
6024 | mmap_event->event_id.header.size = size; | |
0a4a9391 PZ |
6025 | } |
6026 | ||
cdd6c482 | 6027 | static void perf_event_mmap_event(struct perf_mmap_event *mmap_event) |
0a4a9391 | 6028 | { |
089dd79d PZ |
6029 | struct vm_area_struct *vma = mmap_event->vma; |
6030 | struct file *file = vma->vm_file; | |
13d7a241 SE |
6031 | int maj = 0, min = 0; |
6032 | u64 ino = 0, gen = 0; | |
f972eb63 | 6033 | u32 prot = 0, flags = 0; |
0a4a9391 PZ |
6034 | unsigned int size; |
6035 | char tmp[16]; | |
6036 | char *buf = NULL; | |
2c42cfbf | 6037 | char *name; |
413ee3b4 | 6038 | |
0a4a9391 | 6039 | if (file) { |
13d7a241 SE |
6040 | struct inode *inode; |
6041 | dev_t dev; | |
3ea2f2b9 | 6042 | |
2c42cfbf | 6043 | buf = kmalloc(PATH_MAX, GFP_KERNEL); |
0a4a9391 | 6044 | if (!buf) { |
c7e548b4 ON |
6045 | name = "//enomem"; |
6046 | goto cpy_name; | |
0a4a9391 | 6047 | } |
413ee3b4 | 6048 | /* |
3ea2f2b9 | 6049 | * d_path() works from the end of the rb backwards, so we |
413ee3b4 AB |
6050 | * need to add enough zero bytes after the string to handle |
6051 | * the 64bit alignment we do later. | |
6052 | */ | |
9bf39ab2 | 6053 | name = file_path(file, buf, PATH_MAX - sizeof(u64)); |
0a4a9391 | 6054 | if (IS_ERR(name)) { |
c7e548b4 ON |
6055 | name = "//toolong"; |
6056 | goto cpy_name; | |
0a4a9391 | 6057 | } |
13d7a241 SE |
6058 | inode = file_inode(vma->vm_file); |
6059 | dev = inode->i_sb->s_dev; | |
6060 | ino = inode->i_ino; | |
6061 | gen = inode->i_generation; | |
6062 | maj = MAJOR(dev); | |
6063 | min = MINOR(dev); | |
f972eb63 PZ |
6064 | |
6065 | if (vma->vm_flags & VM_READ) | |
6066 | prot |= PROT_READ; | |
6067 | if (vma->vm_flags & VM_WRITE) | |
6068 | prot |= PROT_WRITE; | |
6069 | if (vma->vm_flags & VM_EXEC) | |
6070 | prot |= PROT_EXEC; | |
6071 | ||
6072 | if (vma->vm_flags & VM_MAYSHARE) | |
6073 | flags = MAP_SHARED; | |
6074 | else | |
6075 | flags = MAP_PRIVATE; | |
6076 | ||
6077 | if (vma->vm_flags & VM_DENYWRITE) | |
6078 | flags |= MAP_DENYWRITE; | |
6079 | if (vma->vm_flags & VM_MAYEXEC) | |
6080 | flags |= MAP_EXECUTABLE; | |
6081 | if (vma->vm_flags & VM_LOCKED) | |
6082 | flags |= MAP_LOCKED; | |
6083 | if (vma->vm_flags & VM_HUGETLB) | |
6084 | flags |= MAP_HUGETLB; | |
6085 | ||
c7e548b4 | 6086 | goto got_name; |
0a4a9391 | 6087 | } else { |
fbe26abe JO |
6088 | if (vma->vm_ops && vma->vm_ops->name) { |
6089 | name = (char *) vma->vm_ops->name(vma); | |
6090 | if (name) | |
6091 | goto cpy_name; | |
6092 | } | |
6093 | ||
2c42cfbf | 6094 | name = (char *)arch_vma_name(vma); |
c7e548b4 ON |
6095 | if (name) |
6096 | goto cpy_name; | |
089dd79d | 6097 | |
32c5fb7e | 6098 | if (vma->vm_start <= vma->vm_mm->start_brk && |
3af9e859 | 6099 | vma->vm_end >= vma->vm_mm->brk) { |
c7e548b4 ON |
6100 | name = "[heap]"; |
6101 | goto cpy_name; | |
32c5fb7e ON |
6102 | } |
6103 | if (vma->vm_start <= vma->vm_mm->start_stack && | |
3af9e859 | 6104 | vma->vm_end >= vma->vm_mm->start_stack) { |
c7e548b4 ON |
6105 | name = "[stack]"; |
6106 | goto cpy_name; | |
089dd79d PZ |
6107 | } |
6108 | ||
c7e548b4 ON |
6109 | name = "//anon"; |
6110 | goto cpy_name; | |
0a4a9391 PZ |
6111 | } |
6112 | ||
c7e548b4 ON |
6113 | cpy_name: |
6114 | strlcpy(tmp, name, sizeof(tmp)); | |
6115 | name = tmp; | |
0a4a9391 | 6116 | got_name: |
2c42cfbf PZ |
6117 | /* |
6118 | * Since our buffer works in 8 byte units we need to align our string | |
6119 | * size to a multiple of 8. However, we must guarantee the tail end is | |
6120 | * zero'd out to avoid leaking random bits to userspace. | |
6121 | */ | |
6122 | size = strlen(name)+1; | |
6123 | while (!IS_ALIGNED(size, sizeof(u64))) | |
6124 | name[size++] = '\0'; | |
0a4a9391 PZ |
6125 | |
6126 | mmap_event->file_name = name; | |
6127 | mmap_event->file_size = size; | |
13d7a241 SE |
6128 | mmap_event->maj = maj; |
6129 | mmap_event->min = min; | |
6130 | mmap_event->ino = ino; | |
6131 | mmap_event->ino_generation = gen; | |
f972eb63 PZ |
6132 | mmap_event->prot = prot; |
6133 | mmap_event->flags = flags; | |
0a4a9391 | 6134 | |
2fe85427 SE |
6135 | if (!(vma->vm_flags & VM_EXEC)) |
6136 | mmap_event->event_id.header.misc |= PERF_RECORD_MISC_MMAP_DATA; | |
6137 | ||
cdd6c482 | 6138 | mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size; |
0a4a9391 | 6139 | |
67516844 | 6140 | perf_event_aux(perf_event_mmap_output, |
52d857a8 JO |
6141 | mmap_event, |
6142 | NULL); | |
665c2142 | 6143 | |
0a4a9391 PZ |
6144 | kfree(buf); |
6145 | } | |
6146 | ||
3af9e859 | 6147 | void perf_event_mmap(struct vm_area_struct *vma) |
0a4a9391 | 6148 | { |
9ee318a7 PZ |
6149 | struct perf_mmap_event mmap_event; |
6150 | ||
cdd6c482 | 6151 | if (!atomic_read(&nr_mmap_events)) |
9ee318a7 PZ |
6152 | return; |
6153 | ||
6154 | mmap_event = (struct perf_mmap_event){ | |
089dd79d | 6155 | .vma = vma, |
573402db PZ |
6156 | /* .file_name */ |
6157 | /* .file_size */ | |
cdd6c482 | 6158 | .event_id = { |
573402db | 6159 | .header = { |
cdd6c482 | 6160 | .type = PERF_RECORD_MMAP, |
39447b38 | 6161 | .misc = PERF_RECORD_MISC_USER, |
573402db PZ |
6162 | /* .size */ |
6163 | }, | |
6164 | /* .pid */ | |
6165 | /* .tid */ | |
089dd79d PZ |
6166 | .start = vma->vm_start, |
6167 | .len = vma->vm_end - vma->vm_start, | |
3a0304e9 | 6168 | .pgoff = (u64)vma->vm_pgoff << PAGE_SHIFT, |
0a4a9391 | 6169 | }, |
13d7a241 SE |
6170 | /* .maj (attr_mmap2 only) */ |
6171 | /* .min (attr_mmap2 only) */ | |
6172 | /* .ino (attr_mmap2 only) */ | |
6173 | /* .ino_generation (attr_mmap2 only) */ | |
f972eb63 PZ |
6174 | /* .prot (attr_mmap2 only) */ |
6175 | /* .flags (attr_mmap2 only) */ | |
0a4a9391 PZ |
6176 | }; |
6177 | ||
cdd6c482 | 6178 | perf_event_mmap_event(&mmap_event); |
0a4a9391 PZ |
6179 | } |
6180 | ||
68db7e98 AS |
6181 | void perf_event_aux_event(struct perf_event *event, unsigned long head, |
6182 | unsigned long size, u64 flags) | |
6183 | { | |
6184 | struct perf_output_handle handle; | |
6185 | struct perf_sample_data sample; | |
6186 | struct perf_aux_event { | |
6187 | struct perf_event_header header; | |
6188 | u64 offset; | |
6189 | u64 size; | |
6190 | u64 flags; | |
6191 | } rec = { | |
6192 | .header = { | |
6193 | .type = PERF_RECORD_AUX, | |
6194 | .misc = 0, | |
6195 | .size = sizeof(rec), | |
6196 | }, | |
6197 | .offset = head, | |
6198 | .size = size, | |
6199 | .flags = flags, | |
6200 | }; | |
6201 | int ret; | |
6202 | ||
6203 | perf_event_header__init_id(&rec.header, &sample, event); | |
6204 | ret = perf_output_begin(&handle, event, rec.header.size); | |
6205 | ||
6206 | if (ret) | |
6207 | return; | |
6208 | ||
6209 | perf_output_put(&handle, rec); | |
6210 | perf_event__output_id_sample(event, &handle, &sample); | |
6211 | ||
6212 | perf_output_end(&handle); | |
6213 | } | |
6214 | ||
f38b0dbb KL |
6215 | /* |
6216 | * Lost/dropped samples logging | |
6217 | */ | |
6218 | void perf_log_lost_samples(struct perf_event *event, u64 lost) | |
6219 | { | |
6220 | struct perf_output_handle handle; | |
6221 | struct perf_sample_data sample; | |
6222 | int ret; | |
6223 | ||
6224 | struct { | |
6225 | struct perf_event_header header; | |
6226 | u64 lost; | |
6227 | } lost_samples_event = { | |
6228 | .header = { | |
6229 | .type = PERF_RECORD_LOST_SAMPLES, | |
6230 | .misc = 0, | |
6231 | .size = sizeof(lost_samples_event), | |
6232 | }, | |
6233 | .lost = lost, | |
6234 | }; | |
6235 | ||
6236 | perf_event_header__init_id(&lost_samples_event.header, &sample, event); | |
6237 | ||
6238 | ret = perf_output_begin(&handle, event, | |
6239 | lost_samples_event.header.size); | |
6240 | if (ret) | |
6241 | return; | |
6242 | ||
6243 | perf_output_put(&handle, lost_samples_event); | |
6244 | perf_event__output_id_sample(event, &handle, &sample); | |
6245 | perf_output_end(&handle); | |
6246 | } | |
6247 | ||
45ac1403 AH |
6248 | /* |
6249 | * context_switch tracking | |
6250 | */ | |
6251 | ||
6252 | struct perf_switch_event { | |
6253 | struct task_struct *task; | |
6254 | struct task_struct *next_prev; | |
6255 | ||
6256 | struct { | |
6257 | struct perf_event_header header; | |
6258 | u32 next_prev_pid; | |
6259 | u32 next_prev_tid; | |
6260 | } event_id; | |
6261 | }; | |
6262 | ||
6263 | static int perf_event_switch_match(struct perf_event *event) | |
6264 | { | |
6265 | return event->attr.context_switch; | |
6266 | } | |
6267 | ||
6268 | static void perf_event_switch_output(struct perf_event *event, void *data) | |
6269 | { | |
6270 | struct perf_switch_event *se = data; | |
6271 | struct perf_output_handle handle; | |
6272 | struct perf_sample_data sample; | |
6273 | int ret; | |
6274 | ||
6275 | if (!perf_event_switch_match(event)) | |
6276 | return; | |
6277 | ||
6278 | /* Only CPU-wide events are allowed to see next/prev pid/tid */ | |
6279 | if (event->ctx->task) { | |
6280 | se->event_id.header.type = PERF_RECORD_SWITCH; | |
6281 | se->event_id.header.size = sizeof(se->event_id.header); | |
6282 | } else { | |
6283 | se->event_id.header.type = PERF_RECORD_SWITCH_CPU_WIDE; | |
6284 | se->event_id.header.size = sizeof(se->event_id); | |
6285 | se->event_id.next_prev_pid = | |
6286 | perf_event_pid(event, se->next_prev); | |
6287 | se->event_id.next_prev_tid = | |
6288 | perf_event_tid(event, se->next_prev); | |
6289 | } | |
6290 | ||
6291 | perf_event_header__init_id(&se->event_id.header, &sample, event); | |
6292 | ||
6293 | ret = perf_output_begin(&handle, event, se->event_id.header.size); | |
6294 | if (ret) | |
6295 | return; | |
6296 | ||
6297 | if (event->ctx->task) | |
6298 | perf_output_put(&handle, se->event_id.header); | |
6299 | else | |
6300 | perf_output_put(&handle, se->event_id); | |
6301 | ||
6302 | perf_event__output_id_sample(event, &handle, &sample); | |
6303 | ||
6304 | perf_output_end(&handle); | |
6305 | } | |
6306 | ||
6307 | static void perf_event_switch(struct task_struct *task, | |
6308 | struct task_struct *next_prev, bool sched_in) | |
6309 | { | |
6310 | struct perf_switch_event switch_event; | |
6311 | ||
6312 | /* N.B. caller checks nr_switch_events != 0 */ | |
6313 | ||
6314 | switch_event = (struct perf_switch_event){ | |
6315 | .task = task, | |
6316 | .next_prev = next_prev, | |
6317 | .event_id = { | |
6318 | .header = { | |
6319 | /* .type */ | |
6320 | .misc = sched_in ? 0 : PERF_RECORD_MISC_SWITCH_OUT, | |
6321 | /* .size */ | |
6322 | }, | |
6323 | /* .next_prev_pid */ | |
6324 | /* .next_prev_tid */ | |
6325 | }, | |
6326 | }; | |
6327 | ||
6328 | perf_event_aux(perf_event_switch_output, | |
6329 | &switch_event, | |
6330 | NULL); | |
6331 | } | |
6332 | ||
a78ac325 PZ |
6333 | /* |
6334 | * IRQ throttle logging | |
6335 | */ | |
6336 | ||
cdd6c482 | 6337 | static void perf_log_throttle(struct perf_event *event, int enable) |
a78ac325 PZ |
6338 | { |
6339 | struct perf_output_handle handle; | |
c980d109 | 6340 | struct perf_sample_data sample; |
a78ac325 PZ |
6341 | int ret; |
6342 | ||
6343 | struct { | |
6344 | struct perf_event_header header; | |
6345 | u64 time; | |
cca3f454 | 6346 | u64 id; |
7f453c24 | 6347 | u64 stream_id; |
a78ac325 PZ |
6348 | } throttle_event = { |
6349 | .header = { | |
cdd6c482 | 6350 | .type = PERF_RECORD_THROTTLE, |
a78ac325 PZ |
6351 | .misc = 0, |
6352 | .size = sizeof(throttle_event), | |
6353 | }, | |
34f43927 | 6354 | .time = perf_event_clock(event), |
cdd6c482 IM |
6355 | .id = primary_event_id(event), |
6356 | .stream_id = event->id, | |
a78ac325 PZ |
6357 | }; |
6358 | ||
966ee4d6 | 6359 | if (enable) |
cdd6c482 | 6360 | throttle_event.header.type = PERF_RECORD_UNTHROTTLE; |
966ee4d6 | 6361 | |
c980d109 ACM |
6362 | perf_event_header__init_id(&throttle_event.header, &sample, event); |
6363 | ||
6364 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 6365 | throttle_event.header.size); |
a78ac325 PZ |
6366 | if (ret) |
6367 | return; | |
6368 | ||
6369 | perf_output_put(&handle, throttle_event); | |
c980d109 | 6370 | perf_event__output_id_sample(event, &handle, &sample); |
a78ac325 PZ |
6371 | perf_output_end(&handle); |
6372 | } | |
6373 | ||
ec0d7729 AS |
6374 | static void perf_log_itrace_start(struct perf_event *event) |
6375 | { | |
6376 | struct perf_output_handle handle; | |
6377 | struct perf_sample_data sample; | |
6378 | struct perf_aux_event { | |
6379 | struct perf_event_header header; | |
6380 | u32 pid; | |
6381 | u32 tid; | |
6382 | } rec; | |
6383 | int ret; | |
6384 | ||
6385 | if (event->parent) | |
6386 | event = event->parent; | |
6387 | ||
6388 | if (!(event->pmu->capabilities & PERF_PMU_CAP_ITRACE) || | |
6389 | event->hw.itrace_started) | |
6390 | return; | |
6391 | ||
ec0d7729 AS |
6392 | rec.header.type = PERF_RECORD_ITRACE_START; |
6393 | rec.header.misc = 0; | |
6394 | rec.header.size = sizeof(rec); | |
6395 | rec.pid = perf_event_pid(event, current); | |
6396 | rec.tid = perf_event_tid(event, current); | |
6397 | ||
6398 | perf_event_header__init_id(&rec.header, &sample, event); | |
6399 | ret = perf_output_begin(&handle, event, rec.header.size); | |
6400 | ||
6401 | if (ret) | |
6402 | return; | |
6403 | ||
6404 | perf_output_put(&handle, rec); | |
6405 | perf_event__output_id_sample(event, &handle, &sample); | |
6406 | ||
6407 | perf_output_end(&handle); | |
6408 | } | |
6409 | ||
f6c7d5fe | 6410 | /* |
cdd6c482 | 6411 | * Generic event overflow handling, sampling. |
f6c7d5fe PZ |
6412 | */ |
6413 | ||
a8b0ca17 | 6414 | static int __perf_event_overflow(struct perf_event *event, |
5622f295 MM |
6415 | int throttle, struct perf_sample_data *data, |
6416 | struct pt_regs *regs) | |
f6c7d5fe | 6417 | { |
cdd6c482 IM |
6418 | int events = atomic_read(&event->event_limit); |
6419 | struct hw_perf_event *hwc = &event->hw; | |
e050e3f0 | 6420 | u64 seq; |
79f14641 PZ |
6421 | int ret = 0; |
6422 | ||
96398826 PZ |
6423 | /* |
6424 | * Non-sampling counters might still use the PMI to fold short | |
6425 | * hardware counters, ignore those. | |
6426 | */ | |
6427 | if (unlikely(!is_sampling_event(event))) | |
6428 | return 0; | |
6429 | ||
e050e3f0 SE |
6430 | seq = __this_cpu_read(perf_throttled_seq); |
6431 | if (seq != hwc->interrupts_seq) { | |
6432 | hwc->interrupts_seq = seq; | |
6433 | hwc->interrupts = 1; | |
6434 | } else { | |
6435 | hwc->interrupts++; | |
6436 | if (unlikely(throttle | |
6437 | && hwc->interrupts >= max_samples_per_tick)) { | |
6438 | __this_cpu_inc(perf_throttled_count); | |
555e0c1e | 6439 | tick_dep_set_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
163ec435 PZ |
6440 | hwc->interrupts = MAX_INTERRUPTS; |
6441 | perf_log_throttle(event, 0); | |
a78ac325 PZ |
6442 | ret = 1; |
6443 | } | |
e050e3f0 | 6444 | } |
60db5e09 | 6445 | |
cdd6c482 | 6446 | if (event->attr.freq) { |
def0a9b2 | 6447 | u64 now = perf_clock(); |
abd50713 | 6448 | s64 delta = now - hwc->freq_time_stamp; |
bd2b5b12 | 6449 | |
abd50713 | 6450 | hwc->freq_time_stamp = now; |
bd2b5b12 | 6451 | |
abd50713 | 6452 | if (delta > 0 && delta < 2*TICK_NSEC) |
f39d47ff | 6453 | perf_adjust_period(event, delta, hwc->last_period, true); |
bd2b5b12 PZ |
6454 | } |
6455 | ||
2023b359 PZ |
6456 | /* |
6457 | * XXX event_limit might not quite work as expected on inherited | |
cdd6c482 | 6458 | * events |
2023b359 PZ |
6459 | */ |
6460 | ||
cdd6c482 IM |
6461 | event->pending_kill = POLL_IN; |
6462 | if (events && atomic_dec_and_test(&event->event_limit)) { | |
79f14641 | 6463 | ret = 1; |
cdd6c482 | 6464 | event->pending_kill = POLL_HUP; |
a8b0ca17 PZ |
6465 | event->pending_disable = 1; |
6466 | irq_work_queue(&event->pending); | |
79f14641 PZ |
6467 | } |
6468 | ||
453f19ee | 6469 | if (event->overflow_handler) |
a8b0ca17 | 6470 | event->overflow_handler(event, data, regs); |
453f19ee | 6471 | else |
a8b0ca17 | 6472 | perf_event_output(event, data, regs); |
453f19ee | 6473 | |
fed66e2c | 6474 | if (*perf_event_fasync(event) && event->pending_kill) { |
a8b0ca17 PZ |
6475 | event->pending_wakeup = 1; |
6476 | irq_work_queue(&event->pending); | |
f506b3dc PZ |
6477 | } |
6478 | ||
79f14641 | 6479 | return ret; |
f6c7d5fe PZ |
6480 | } |
6481 | ||
a8b0ca17 | 6482 | int perf_event_overflow(struct perf_event *event, |
5622f295 MM |
6483 | struct perf_sample_data *data, |
6484 | struct pt_regs *regs) | |
850bc73f | 6485 | { |
a8b0ca17 | 6486 | return __perf_event_overflow(event, 1, data, regs); |
850bc73f PZ |
6487 | } |
6488 | ||
15dbf27c | 6489 | /* |
cdd6c482 | 6490 | * Generic software event infrastructure |
15dbf27c PZ |
6491 | */ |
6492 | ||
b28ab83c PZ |
6493 | struct swevent_htable { |
6494 | struct swevent_hlist *swevent_hlist; | |
6495 | struct mutex hlist_mutex; | |
6496 | int hlist_refcount; | |
6497 | ||
6498 | /* Recursion avoidance in each contexts */ | |
6499 | int recursion[PERF_NR_CONTEXTS]; | |
6500 | }; | |
6501 | ||
6502 | static DEFINE_PER_CPU(struct swevent_htable, swevent_htable); | |
6503 | ||
7b4b6658 | 6504 | /* |
cdd6c482 IM |
6505 | * We directly increment event->count and keep a second value in |
6506 | * event->hw.period_left to count intervals. This period event | |
7b4b6658 PZ |
6507 | * is kept in the range [-sample_period, 0] so that we can use the |
6508 | * sign as trigger. | |
6509 | */ | |
6510 | ||
ab573844 | 6511 | u64 perf_swevent_set_period(struct perf_event *event) |
15dbf27c | 6512 | { |
cdd6c482 | 6513 | struct hw_perf_event *hwc = &event->hw; |
7b4b6658 PZ |
6514 | u64 period = hwc->last_period; |
6515 | u64 nr, offset; | |
6516 | s64 old, val; | |
6517 | ||
6518 | hwc->last_period = hwc->sample_period; | |
15dbf27c PZ |
6519 | |
6520 | again: | |
e7850595 | 6521 | old = val = local64_read(&hwc->period_left); |
7b4b6658 PZ |
6522 | if (val < 0) |
6523 | return 0; | |
15dbf27c | 6524 | |
7b4b6658 PZ |
6525 | nr = div64_u64(period + val, period); |
6526 | offset = nr * period; | |
6527 | val -= offset; | |
e7850595 | 6528 | if (local64_cmpxchg(&hwc->period_left, old, val) != old) |
7b4b6658 | 6529 | goto again; |
15dbf27c | 6530 | |
7b4b6658 | 6531 | return nr; |
15dbf27c PZ |
6532 | } |
6533 | ||
0cff784a | 6534 | static void perf_swevent_overflow(struct perf_event *event, u64 overflow, |
a8b0ca17 | 6535 | struct perf_sample_data *data, |
5622f295 | 6536 | struct pt_regs *regs) |
15dbf27c | 6537 | { |
cdd6c482 | 6538 | struct hw_perf_event *hwc = &event->hw; |
850bc73f | 6539 | int throttle = 0; |
15dbf27c | 6540 | |
0cff784a PZ |
6541 | if (!overflow) |
6542 | overflow = perf_swevent_set_period(event); | |
15dbf27c | 6543 | |
7b4b6658 PZ |
6544 | if (hwc->interrupts == MAX_INTERRUPTS) |
6545 | return; | |
15dbf27c | 6546 | |
7b4b6658 | 6547 | for (; overflow; overflow--) { |
a8b0ca17 | 6548 | if (__perf_event_overflow(event, throttle, |
5622f295 | 6549 | data, regs)) { |
7b4b6658 PZ |
6550 | /* |
6551 | * We inhibit the overflow from happening when | |
6552 | * hwc->interrupts == MAX_INTERRUPTS. | |
6553 | */ | |
6554 | break; | |
6555 | } | |
cf450a73 | 6556 | throttle = 1; |
7b4b6658 | 6557 | } |
15dbf27c PZ |
6558 | } |
6559 | ||
a4eaf7f1 | 6560 | static void perf_swevent_event(struct perf_event *event, u64 nr, |
a8b0ca17 | 6561 | struct perf_sample_data *data, |
5622f295 | 6562 | struct pt_regs *regs) |
7b4b6658 | 6563 | { |
cdd6c482 | 6564 | struct hw_perf_event *hwc = &event->hw; |
d6d020e9 | 6565 | |
e7850595 | 6566 | local64_add(nr, &event->count); |
d6d020e9 | 6567 | |
0cff784a PZ |
6568 | if (!regs) |
6569 | return; | |
6570 | ||
6c7e550f | 6571 | if (!is_sampling_event(event)) |
7b4b6658 | 6572 | return; |
d6d020e9 | 6573 | |
5d81e5cf AV |
6574 | if ((event->attr.sample_type & PERF_SAMPLE_PERIOD) && !event->attr.freq) { |
6575 | data->period = nr; | |
6576 | return perf_swevent_overflow(event, 1, data, regs); | |
6577 | } else | |
6578 | data->period = event->hw.last_period; | |
6579 | ||
0cff784a | 6580 | if (nr == 1 && hwc->sample_period == 1 && !event->attr.freq) |
a8b0ca17 | 6581 | return perf_swevent_overflow(event, 1, data, regs); |
0cff784a | 6582 | |
e7850595 | 6583 | if (local64_add_negative(nr, &hwc->period_left)) |
7b4b6658 | 6584 | return; |
df1a132b | 6585 | |
a8b0ca17 | 6586 | perf_swevent_overflow(event, 0, data, regs); |
d6d020e9 PZ |
6587 | } |
6588 | ||
f5ffe02e FW |
6589 | static int perf_exclude_event(struct perf_event *event, |
6590 | struct pt_regs *regs) | |
6591 | { | |
a4eaf7f1 | 6592 | if (event->hw.state & PERF_HES_STOPPED) |
91b2f482 | 6593 | return 1; |
a4eaf7f1 | 6594 | |
f5ffe02e FW |
6595 | if (regs) { |
6596 | if (event->attr.exclude_user && user_mode(regs)) | |
6597 | return 1; | |
6598 | ||
6599 | if (event->attr.exclude_kernel && !user_mode(regs)) | |
6600 | return 1; | |
6601 | } | |
6602 | ||
6603 | return 0; | |
6604 | } | |
6605 | ||
cdd6c482 | 6606 | static int perf_swevent_match(struct perf_event *event, |
1c432d89 | 6607 | enum perf_type_id type, |
6fb2915d LZ |
6608 | u32 event_id, |
6609 | struct perf_sample_data *data, | |
6610 | struct pt_regs *regs) | |
15dbf27c | 6611 | { |
cdd6c482 | 6612 | if (event->attr.type != type) |
a21ca2ca | 6613 | return 0; |
f5ffe02e | 6614 | |
cdd6c482 | 6615 | if (event->attr.config != event_id) |
15dbf27c PZ |
6616 | return 0; |
6617 | ||
f5ffe02e FW |
6618 | if (perf_exclude_event(event, regs)) |
6619 | return 0; | |
15dbf27c PZ |
6620 | |
6621 | return 1; | |
6622 | } | |
6623 | ||
76e1d904 FW |
6624 | static inline u64 swevent_hash(u64 type, u32 event_id) |
6625 | { | |
6626 | u64 val = event_id | (type << 32); | |
6627 | ||
6628 | return hash_64(val, SWEVENT_HLIST_BITS); | |
6629 | } | |
6630 | ||
49f135ed FW |
6631 | static inline struct hlist_head * |
6632 | __find_swevent_head(struct swevent_hlist *hlist, u64 type, u32 event_id) | |
76e1d904 | 6633 | { |
49f135ed FW |
6634 | u64 hash = swevent_hash(type, event_id); |
6635 | ||
6636 | return &hlist->heads[hash]; | |
6637 | } | |
76e1d904 | 6638 | |
49f135ed FW |
6639 | /* For the read side: events when they trigger */ |
6640 | static inline struct hlist_head * | |
b28ab83c | 6641 | find_swevent_head_rcu(struct swevent_htable *swhash, u64 type, u32 event_id) |
49f135ed FW |
6642 | { |
6643 | struct swevent_hlist *hlist; | |
76e1d904 | 6644 | |
b28ab83c | 6645 | hlist = rcu_dereference(swhash->swevent_hlist); |
76e1d904 FW |
6646 | if (!hlist) |
6647 | return NULL; | |
6648 | ||
49f135ed FW |
6649 | return __find_swevent_head(hlist, type, event_id); |
6650 | } | |
6651 | ||
6652 | /* For the event head insertion and removal in the hlist */ | |
6653 | static inline struct hlist_head * | |
b28ab83c | 6654 | find_swevent_head(struct swevent_htable *swhash, struct perf_event *event) |
49f135ed FW |
6655 | { |
6656 | struct swevent_hlist *hlist; | |
6657 | u32 event_id = event->attr.config; | |
6658 | u64 type = event->attr.type; | |
6659 | ||
6660 | /* | |
6661 | * Event scheduling is always serialized against hlist allocation | |
6662 | * and release. Which makes the protected version suitable here. | |
6663 | * The context lock guarantees that. | |
6664 | */ | |
b28ab83c | 6665 | hlist = rcu_dereference_protected(swhash->swevent_hlist, |
49f135ed FW |
6666 | lockdep_is_held(&event->ctx->lock)); |
6667 | if (!hlist) | |
6668 | return NULL; | |
6669 | ||
6670 | return __find_swevent_head(hlist, type, event_id); | |
76e1d904 FW |
6671 | } |
6672 | ||
6673 | static void do_perf_sw_event(enum perf_type_id type, u32 event_id, | |
a8b0ca17 | 6674 | u64 nr, |
76e1d904 FW |
6675 | struct perf_sample_data *data, |
6676 | struct pt_regs *regs) | |
15dbf27c | 6677 | { |
4a32fea9 | 6678 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 6679 | struct perf_event *event; |
76e1d904 | 6680 | struct hlist_head *head; |
15dbf27c | 6681 | |
76e1d904 | 6682 | rcu_read_lock(); |
b28ab83c | 6683 | head = find_swevent_head_rcu(swhash, type, event_id); |
76e1d904 FW |
6684 | if (!head) |
6685 | goto end; | |
6686 | ||
b67bfe0d | 6687 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
6fb2915d | 6688 | if (perf_swevent_match(event, type, event_id, data, regs)) |
a8b0ca17 | 6689 | perf_swevent_event(event, nr, data, regs); |
15dbf27c | 6690 | } |
76e1d904 FW |
6691 | end: |
6692 | rcu_read_unlock(); | |
15dbf27c PZ |
6693 | } |
6694 | ||
86038c5e PZI |
6695 | DEFINE_PER_CPU(struct pt_regs, __perf_regs[4]); |
6696 | ||
4ed7c92d | 6697 | int perf_swevent_get_recursion_context(void) |
96f6d444 | 6698 | { |
4a32fea9 | 6699 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
96f6d444 | 6700 | |
b28ab83c | 6701 | return get_recursion_context(swhash->recursion); |
96f6d444 | 6702 | } |
645e8cc0 | 6703 | EXPORT_SYMBOL_GPL(perf_swevent_get_recursion_context); |
96f6d444 | 6704 | |
fa9f90be | 6705 | inline void perf_swevent_put_recursion_context(int rctx) |
15dbf27c | 6706 | { |
4a32fea9 | 6707 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
927c7a9e | 6708 | |
b28ab83c | 6709 | put_recursion_context(swhash->recursion, rctx); |
ce71b9df | 6710 | } |
15dbf27c | 6711 | |
86038c5e | 6712 | void ___perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) |
b8e83514 | 6713 | { |
a4234bfc | 6714 | struct perf_sample_data data; |
4ed7c92d | 6715 | |
86038c5e | 6716 | if (WARN_ON_ONCE(!regs)) |
4ed7c92d | 6717 | return; |
a4234bfc | 6718 | |
fd0d000b | 6719 | perf_sample_data_init(&data, addr, 0); |
a8b0ca17 | 6720 | do_perf_sw_event(PERF_TYPE_SOFTWARE, event_id, nr, &data, regs); |
86038c5e PZI |
6721 | } |
6722 | ||
6723 | void __perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) | |
6724 | { | |
6725 | int rctx; | |
6726 | ||
6727 | preempt_disable_notrace(); | |
6728 | rctx = perf_swevent_get_recursion_context(); | |
6729 | if (unlikely(rctx < 0)) | |
6730 | goto fail; | |
6731 | ||
6732 | ___perf_sw_event(event_id, nr, regs, addr); | |
4ed7c92d PZ |
6733 | |
6734 | perf_swevent_put_recursion_context(rctx); | |
86038c5e | 6735 | fail: |
1c024eca | 6736 | preempt_enable_notrace(); |
b8e83514 PZ |
6737 | } |
6738 | ||
cdd6c482 | 6739 | static void perf_swevent_read(struct perf_event *event) |
15dbf27c | 6740 | { |
15dbf27c PZ |
6741 | } |
6742 | ||
a4eaf7f1 | 6743 | static int perf_swevent_add(struct perf_event *event, int flags) |
15dbf27c | 6744 | { |
4a32fea9 | 6745 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 6746 | struct hw_perf_event *hwc = &event->hw; |
76e1d904 FW |
6747 | struct hlist_head *head; |
6748 | ||
6c7e550f | 6749 | if (is_sampling_event(event)) { |
7b4b6658 | 6750 | hwc->last_period = hwc->sample_period; |
cdd6c482 | 6751 | perf_swevent_set_period(event); |
7b4b6658 | 6752 | } |
76e1d904 | 6753 | |
a4eaf7f1 PZ |
6754 | hwc->state = !(flags & PERF_EF_START); |
6755 | ||
b28ab83c | 6756 | head = find_swevent_head(swhash, event); |
12ca6ad2 | 6757 | if (WARN_ON_ONCE(!head)) |
76e1d904 FW |
6758 | return -EINVAL; |
6759 | ||
6760 | hlist_add_head_rcu(&event->hlist_entry, head); | |
6a694a60 | 6761 | perf_event_update_userpage(event); |
76e1d904 | 6762 | |
15dbf27c PZ |
6763 | return 0; |
6764 | } | |
6765 | ||
a4eaf7f1 | 6766 | static void perf_swevent_del(struct perf_event *event, int flags) |
15dbf27c | 6767 | { |
76e1d904 | 6768 | hlist_del_rcu(&event->hlist_entry); |
15dbf27c PZ |
6769 | } |
6770 | ||
a4eaf7f1 | 6771 | static void perf_swevent_start(struct perf_event *event, int flags) |
5c92d124 | 6772 | { |
a4eaf7f1 | 6773 | event->hw.state = 0; |
d6d020e9 | 6774 | } |
aa9c4c0f | 6775 | |
a4eaf7f1 | 6776 | static void perf_swevent_stop(struct perf_event *event, int flags) |
d6d020e9 | 6777 | { |
a4eaf7f1 | 6778 | event->hw.state = PERF_HES_STOPPED; |
bae43c99 IM |
6779 | } |
6780 | ||
49f135ed FW |
6781 | /* Deref the hlist from the update side */ |
6782 | static inline struct swevent_hlist * | |
b28ab83c | 6783 | swevent_hlist_deref(struct swevent_htable *swhash) |
49f135ed | 6784 | { |
b28ab83c PZ |
6785 | return rcu_dereference_protected(swhash->swevent_hlist, |
6786 | lockdep_is_held(&swhash->hlist_mutex)); | |
49f135ed FW |
6787 | } |
6788 | ||
b28ab83c | 6789 | static void swevent_hlist_release(struct swevent_htable *swhash) |
76e1d904 | 6790 | { |
b28ab83c | 6791 | struct swevent_hlist *hlist = swevent_hlist_deref(swhash); |
76e1d904 | 6792 | |
49f135ed | 6793 | if (!hlist) |
76e1d904 FW |
6794 | return; |
6795 | ||
70691d4a | 6796 | RCU_INIT_POINTER(swhash->swevent_hlist, NULL); |
fa4bbc4c | 6797 | kfree_rcu(hlist, rcu_head); |
76e1d904 FW |
6798 | } |
6799 | ||
3b364d7b | 6800 | static void swevent_hlist_put_cpu(int cpu) |
76e1d904 | 6801 | { |
b28ab83c | 6802 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 | 6803 | |
b28ab83c | 6804 | mutex_lock(&swhash->hlist_mutex); |
76e1d904 | 6805 | |
b28ab83c PZ |
6806 | if (!--swhash->hlist_refcount) |
6807 | swevent_hlist_release(swhash); | |
76e1d904 | 6808 | |
b28ab83c | 6809 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
6810 | } |
6811 | ||
3b364d7b | 6812 | static void swevent_hlist_put(void) |
76e1d904 FW |
6813 | { |
6814 | int cpu; | |
6815 | ||
76e1d904 | 6816 | for_each_possible_cpu(cpu) |
3b364d7b | 6817 | swevent_hlist_put_cpu(cpu); |
76e1d904 FW |
6818 | } |
6819 | ||
3b364d7b | 6820 | static int swevent_hlist_get_cpu(int cpu) |
76e1d904 | 6821 | { |
b28ab83c | 6822 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 FW |
6823 | int err = 0; |
6824 | ||
b28ab83c | 6825 | mutex_lock(&swhash->hlist_mutex); |
b28ab83c | 6826 | if (!swevent_hlist_deref(swhash) && cpu_online(cpu)) { |
76e1d904 FW |
6827 | struct swevent_hlist *hlist; |
6828 | ||
6829 | hlist = kzalloc(sizeof(*hlist), GFP_KERNEL); | |
6830 | if (!hlist) { | |
6831 | err = -ENOMEM; | |
6832 | goto exit; | |
6833 | } | |
b28ab83c | 6834 | rcu_assign_pointer(swhash->swevent_hlist, hlist); |
76e1d904 | 6835 | } |
b28ab83c | 6836 | swhash->hlist_refcount++; |
9ed6060d | 6837 | exit: |
b28ab83c | 6838 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
6839 | |
6840 | return err; | |
6841 | } | |
6842 | ||
3b364d7b | 6843 | static int swevent_hlist_get(void) |
76e1d904 | 6844 | { |
3b364d7b | 6845 | int err, cpu, failed_cpu; |
76e1d904 | 6846 | |
76e1d904 FW |
6847 | get_online_cpus(); |
6848 | for_each_possible_cpu(cpu) { | |
3b364d7b | 6849 | err = swevent_hlist_get_cpu(cpu); |
76e1d904 FW |
6850 | if (err) { |
6851 | failed_cpu = cpu; | |
6852 | goto fail; | |
6853 | } | |
6854 | } | |
6855 | put_online_cpus(); | |
6856 | ||
6857 | return 0; | |
9ed6060d | 6858 | fail: |
76e1d904 FW |
6859 | for_each_possible_cpu(cpu) { |
6860 | if (cpu == failed_cpu) | |
6861 | break; | |
3b364d7b | 6862 | swevent_hlist_put_cpu(cpu); |
76e1d904 FW |
6863 | } |
6864 | ||
6865 | put_online_cpus(); | |
6866 | return err; | |
6867 | } | |
6868 | ||
c5905afb | 6869 | struct static_key perf_swevent_enabled[PERF_COUNT_SW_MAX]; |
95476b64 | 6870 | |
b0a873eb PZ |
6871 | static void sw_perf_event_destroy(struct perf_event *event) |
6872 | { | |
6873 | u64 event_id = event->attr.config; | |
95476b64 | 6874 | |
b0a873eb PZ |
6875 | WARN_ON(event->parent); |
6876 | ||
c5905afb | 6877 | static_key_slow_dec(&perf_swevent_enabled[event_id]); |
3b364d7b | 6878 | swevent_hlist_put(); |
b0a873eb PZ |
6879 | } |
6880 | ||
6881 | static int perf_swevent_init(struct perf_event *event) | |
6882 | { | |
8176cced | 6883 | u64 event_id = event->attr.config; |
b0a873eb PZ |
6884 | |
6885 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
6886 | return -ENOENT; | |
6887 | ||
2481c5fa SE |
6888 | /* |
6889 | * no branch sampling for software events | |
6890 | */ | |
6891 | if (has_branch_stack(event)) | |
6892 | return -EOPNOTSUPP; | |
6893 | ||
b0a873eb PZ |
6894 | switch (event_id) { |
6895 | case PERF_COUNT_SW_CPU_CLOCK: | |
6896 | case PERF_COUNT_SW_TASK_CLOCK: | |
6897 | return -ENOENT; | |
6898 | ||
6899 | default: | |
6900 | break; | |
6901 | } | |
6902 | ||
ce677831 | 6903 | if (event_id >= PERF_COUNT_SW_MAX) |
b0a873eb PZ |
6904 | return -ENOENT; |
6905 | ||
6906 | if (!event->parent) { | |
6907 | int err; | |
6908 | ||
3b364d7b | 6909 | err = swevent_hlist_get(); |
b0a873eb PZ |
6910 | if (err) |
6911 | return err; | |
6912 | ||
c5905afb | 6913 | static_key_slow_inc(&perf_swevent_enabled[event_id]); |
b0a873eb PZ |
6914 | event->destroy = sw_perf_event_destroy; |
6915 | } | |
6916 | ||
6917 | return 0; | |
6918 | } | |
6919 | ||
6920 | static struct pmu perf_swevent = { | |
89a1e187 | 6921 | .task_ctx_nr = perf_sw_context, |
95476b64 | 6922 | |
34f43927 PZ |
6923 | .capabilities = PERF_PMU_CAP_NO_NMI, |
6924 | ||
b0a873eb | 6925 | .event_init = perf_swevent_init, |
a4eaf7f1 PZ |
6926 | .add = perf_swevent_add, |
6927 | .del = perf_swevent_del, | |
6928 | .start = perf_swevent_start, | |
6929 | .stop = perf_swevent_stop, | |
1c024eca | 6930 | .read = perf_swevent_read, |
1c024eca PZ |
6931 | }; |
6932 | ||
b0a873eb PZ |
6933 | #ifdef CONFIG_EVENT_TRACING |
6934 | ||
1c024eca PZ |
6935 | static int perf_tp_filter_match(struct perf_event *event, |
6936 | struct perf_sample_data *data) | |
6937 | { | |
6938 | void *record = data->raw->data; | |
6939 | ||
b71b437e PZ |
6940 | /* only top level events have filters set */ |
6941 | if (event->parent) | |
6942 | event = event->parent; | |
6943 | ||
1c024eca PZ |
6944 | if (likely(!event->filter) || filter_match_preds(event->filter, record)) |
6945 | return 1; | |
6946 | return 0; | |
6947 | } | |
6948 | ||
6949 | static int perf_tp_event_match(struct perf_event *event, | |
6950 | struct perf_sample_data *data, | |
6951 | struct pt_regs *regs) | |
6952 | { | |
a0f7d0f7 FW |
6953 | if (event->hw.state & PERF_HES_STOPPED) |
6954 | return 0; | |
580d607c PZ |
6955 | /* |
6956 | * All tracepoints are from kernel-space. | |
6957 | */ | |
6958 | if (event->attr.exclude_kernel) | |
1c024eca PZ |
6959 | return 0; |
6960 | ||
6961 | if (!perf_tp_filter_match(event, data)) | |
6962 | return 0; | |
6963 | ||
6964 | return 1; | |
6965 | } | |
6966 | ||
6967 | void perf_tp_event(u64 addr, u64 count, void *record, int entry_size, | |
e6dab5ff AV |
6968 | struct pt_regs *regs, struct hlist_head *head, int rctx, |
6969 | struct task_struct *task) | |
95476b64 FW |
6970 | { |
6971 | struct perf_sample_data data; | |
1c024eca | 6972 | struct perf_event *event; |
1c024eca | 6973 | |
95476b64 FW |
6974 | struct perf_raw_record raw = { |
6975 | .size = entry_size, | |
6976 | .data = record, | |
6977 | }; | |
6978 | ||
fd0d000b | 6979 | perf_sample_data_init(&data, addr, 0); |
95476b64 FW |
6980 | data.raw = &raw; |
6981 | ||
b67bfe0d | 6982 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
1c024eca | 6983 | if (perf_tp_event_match(event, &data, regs)) |
a8b0ca17 | 6984 | perf_swevent_event(event, count, &data, regs); |
4f41c013 | 6985 | } |
ecc55f84 | 6986 | |
e6dab5ff AV |
6987 | /* |
6988 | * If we got specified a target task, also iterate its context and | |
6989 | * deliver this event there too. | |
6990 | */ | |
6991 | if (task && task != current) { | |
6992 | struct perf_event_context *ctx; | |
6993 | struct trace_entry *entry = record; | |
6994 | ||
6995 | rcu_read_lock(); | |
6996 | ctx = rcu_dereference(task->perf_event_ctxp[perf_sw_context]); | |
6997 | if (!ctx) | |
6998 | goto unlock; | |
6999 | ||
7000 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
7001 | if (event->attr.type != PERF_TYPE_TRACEPOINT) | |
7002 | continue; | |
7003 | if (event->attr.config != entry->type) | |
7004 | continue; | |
7005 | if (perf_tp_event_match(event, &data, regs)) | |
7006 | perf_swevent_event(event, count, &data, regs); | |
7007 | } | |
7008 | unlock: | |
7009 | rcu_read_unlock(); | |
7010 | } | |
7011 | ||
ecc55f84 | 7012 | perf_swevent_put_recursion_context(rctx); |
95476b64 FW |
7013 | } |
7014 | EXPORT_SYMBOL_GPL(perf_tp_event); | |
7015 | ||
cdd6c482 | 7016 | static void tp_perf_event_destroy(struct perf_event *event) |
e077df4f | 7017 | { |
1c024eca | 7018 | perf_trace_destroy(event); |
e077df4f PZ |
7019 | } |
7020 | ||
b0a873eb | 7021 | static int perf_tp_event_init(struct perf_event *event) |
e077df4f | 7022 | { |
76e1d904 FW |
7023 | int err; |
7024 | ||
b0a873eb PZ |
7025 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
7026 | return -ENOENT; | |
7027 | ||
2481c5fa SE |
7028 | /* |
7029 | * no branch sampling for tracepoint events | |
7030 | */ | |
7031 | if (has_branch_stack(event)) | |
7032 | return -EOPNOTSUPP; | |
7033 | ||
1c024eca PZ |
7034 | err = perf_trace_init(event); |
7035 | if (err) | |
b0a873eb | 7036 | return err; |
e077df4f | 7037 | |
cdd6c482 | 7038 | event->destroy = tp_perf_event_destroy; |
e077df4f | 7039 | |
b0a873eb PZ |
7040 | return 0; |
7041 | } | |
7042 | ||
7043 | static struct pmu perf_tracepoint = { | |
89a1e187 PZ |
7044 | .task_ctx_nr = perf_sw_context, |
7045 | ||
b0a873eb | 7046 | .event_init = perf_tp_event_init, |
a4eaf7f1 PZ |
7047 | .add = perf_trace_add, |
7048 | .del = perf_trace_del, | |
7049 | .start = perf_swevent_start, | |
7050 | .stop = perf_swevent_stop, | |
b0a873eb | 7051 | .read = perf_swevent_read, |
b0a873eb PZ |
7052 | }; |
7053 | ||
7054 | static inline void perf_tp_register(void) | |
7055 | { | |
2e80a82a | 7056 | perf_pmu_register(&perf_tracepoint, "tracepoint", PERF_TYPE_TRACEPOINT); |
e077df4f | 7057 | } |
6fb2915d LZ |
7058 | |
7059 | static int perf_event_set_filter(struct perf_event *event, void __user *arg) | |
7060 | { | |
7061 | char *filter_str; | |
7062 | int ret; | |
7063 | ||
7064 | if (event->attr.type != PERF_TYPE_TRACEPOINT) | |
7065 | return -EINVAL; | |
7066 | ||
7067 | filter_str = strndup_user(arg, PAGE_SIZE); | |
7068 | if (IS_ERR(filter_str)) | |
7069 | return PTR_ERR(filter_str); | |
7070 | ||
7071 | ret = ftrace_profile_set_filter(event, event->attr.config, filter_str); | |
7072 | ||
7073 | kfree(filter_str); | |
7074 | return ret; | |
7075 | } | |
7076 | ||
7077 | static void perf_event_free_filter(struct perf_event *event) | |
7078 | { | |
7079 | ftrace_profile_free_filter(event); | |
7080 | } | |
7081 | ||
2541517c AS |
7082 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
7083 | { | |
7084 | struct bpf_prog *prog; | |
7085 | ||
7086 | if (event->attr.type != PERF_TYPE_TRACEPOINT) | |
7087 | return -EINVAL; | |
7088 | ||
7089 | if (event->tp_event->prog) | |
7090 | return -EEXIST; | |
7091 | ||
04a22fae WN |
7092 | if (!(event->tp_event->flags & TRACE_EVENT_FL_UKPROBE)) |
7093 | /* bpf programs can only be attached to u/kprobes */ | |
2541517c AS |
7094 | return -EINVAL; |
7095 | ||
7096 | prog = bpf_prog_get(prog_fd); | |
7097 | if (IS_ERR(prog)) | |
7098 | return PTR_ERR(prog); | |
7099 | ||
6c373ca8 | 7100 | if (prog->type != BPF_PROG_TYPE_KPROBE) { |
2541517c AS |
7101 | /* valid fd, but invalid bpf program type */ |
7102 | bpf_prog_put(prog); | |
7103 | return -EINVAL; | |
7104 | } | |
7105 | ||
7106 | event->tp_event->prog = prog; | |
7107 | ||
7108 | return 0; | |
7109 | } | |
7110 | ||
7111 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
7112 | { | |
7113 | struct bpf_prog *prog; | |
7114 | ||
7115 | if (!event->tp_event) | |
7116 | return; | |
7117 | ||
7118 | prog = event->tp_event->prog; | |
7119 | if (prog) { | |
7120 | event->tp_event->prog = NULL; | |
7121 | bpf_prog_put(prog); | |
7122 | } | |
7123 | } | |
7124 | ||
e077df4f | 7125 | #else |
6fb2915d | 7126 | |
b0a873eb | 7127 | static inline void perf_tp_register(void) |
e077df4f | 7128 | { |
e077df4f | 7129 | } |
6fb2915d LZ |
7130 | |
7131 | static int perf_event_set_filter(struct perf_event *event, void __user *arg) | |
7132 | { | |
7133 | return -ENOENT; | |
7134 | } | |
7135 | ||
7136 | static void perf_event_free_filter(struct perf_event *event) | |
7137 | { | |
7138 | } | |
7139 | ||
2541517c AS |
7140 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
7141 | { | |
7142 | return -ENOENT; | |
7143 | } | |
7144 | ||
7145 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
7146 | { | |
7147 | } | |
07b139c8 | 7148 | #endif /* CONFIG_EVENT_TRACING */ |
e077df4f | 7149 | |
24f1e32c | 7150 | #ifdef CONFIG_HAVE_HW_BREAKPOINT |
f5ffe02e | 7151 | void perf_bp_event(struct perf_event *bp, void *data) |
24f1e32c | 7152 | { |
f5ffe02e FW |
7153 | struct perf_sample_data sample; |
7154 | struct pt_regs *regs = data; | |
7155 | ||
fd0d000b | 7156 | perf_sample_data_init(&sample, bp->attr.bp_addr, 0); |
f5ffe02e | 7157 | |
a4eaf7f1 | 7158 | if (!bp->hw.state && !perf_exclude_event(bp, regs)) |
a8b0ca17 | 7159 | perf_swevent_event(bp, 1, &sample, regs); |
24f1e32c FW |
7160 | } |
7161 | #endif | |
7162 | ||
b0a873eb PZ |
7163 | /* |
7164 | * hrtimer based swevent callback | |
7165 | */ | |
f29ac756 | 7166 | |
b0a873eb | 7167 | static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer) |
f29ac756 | 7168 | { |
b0a873eb PZ |
7169 | enum hrtimer_restart ret = HRTIMER_RESTART; |
7170 | struct perf_sample_data data; | |
7171 | struct pt_regs *regs; | |
7172 | struct perf_event *event; | |
7173 | u64 period; | |
f29ac756 | 7174 | |
b0a873eb | 7175 | event = container_of(hrtimer, struct perf_event, hw.hrtimer); |
ba3dd36c PZ |
7176 | |
7177 | if (event->state != PERF_EVENT_STATE_ACTIVE) | |
7178 | return HRTIMER_NORESTART; | |
7179 | ||
b0a873eb | 7180 | event->pmu->read(event); |
f344011c | 7181 | |
fd0d000b | 7182 | perf_sample_data_init(&data, 0, event->hw.last_period); |
b0a873eb PZ |
7183 | regs = get_irq_regs(); |
7184 | ||
7185 | if (regs && !perf_exclude_event(event, regs)) { | |
77aeeebd | 7186 | if (!(event->attr.exclude_idle && is_idle_task(current))) |
33b07b8b | 7187 | if (__perf_event_overflow(event, 1, &data, regs)) |
b0a873eb PZ |
7188 | ret = HRTIMER_NORESTART; |
7189 | } | |
24f1e32c | 7190 | |
b0a873eb PZ |
7191 | period = max_t(u64, 10000, event->hw.sample_period); |
7192 | hrtimer_forward_now(hrtimer, ns_to_ktime(period)); | |
24f1e32c | 7193 | |
b0a873eb | 7194 | return ret; |
f29ac756 PZ |
7195 | } |
7196 | ||
b0a873eb | 7197 | static void perf_swevent_start_hrtimer(struct perf_event *event) |
5c92d124 | 7198 | { |
b0a873eb | 7199 | struct hw_perf_event *hwc = &event->hw; |
5d508e82 FBH |
7200 | s64 period; |
7201 | ||
7202 | if (!is_sampling_event(event)) | |
7203 | return; | |
f5ffe02e | 7204 | |
5d508e82 FBH |
7205 | period = local64_read(&hwc->period_left); |
7206 | if (period) { | |
7207 | if (period < 0) | |
7208 | period = 10000; | |
fa407f35 | 7209 | |
5d508e82 FBH |
7210 | local64_set(&hwc->period_left, 0); |
7211 | } else { | |
7212 | period = max_t(u64, 10000, hwc->sample_period); | |
7213 | } | |
3497d206 TG |
7214 | hrtimer_start(&hwc->hrtimer, ns_to_ktime(period), |
7215 | HRTIMER_MODE_REL_PINNED); | |
24f1e32c | 7216 | } |
b0a873eb PZ |
7217 | |
7218 | static void perf_swevent_cancel_hrtimer(struct perf_event *event) | |
24f1e32c | 7219 | { |
b0a873eb PZ |
7220 | struct hw_perf_event *hwc = &event->hw; |
7221 | ||
6c7e550f | 7222 | if (is_sampling_event(event)) { |
b0a873eb | 7223 | ktime_t remaining = hrtimer_get_remaining(&hwc->hrtimer); |
fa407f35 | 7224 | local64_set(&hwc->period_left, ktime_to_ns(remaining)); |
b0a873eb PZ |
7225 | |
7226 | hrtimer_cancel(&hwc->hrtimer); | |
7227 | } | |
24f1e32c FW |
7228 | } |
7229 | ||
ba3dd36c PZ |
7230 | static void perf_swevent_init_hrtimer(struct perf_event *event) |
7231 | { | |
7232 | struct hw_perf_event *hwc = &event->hw; | |
7233 | ||
7234 | if (!is_sampling_event(event)) | |
7235 | return; | |
7236 | ||
7237 | hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); | |
7238 | hwc->hrtimer.function = perf_swevent_hrtimer; | |
7239 | ||
7240 | /* | |
7241 | * Since hrtimers have a fixed rate, we can do a static freq->period | |
7242 | * mapping and avoid the whole period adjust feedback stuff. | |
7243 | */ | |
7244 | if (event->attr.freq) { | |
7245 | long freq = event->attr.sample_freq; | |
7246 | ||
7247 | event->attr.sample_period = NSEC_PER_SEC / freq; | |
7248 | hwc->sample_period = event->attr.sample_period; | |
7249 | local64_set(&hwc->period_left, hwc->sample_period); | |
778141e3 | 7250 | hwc->last_period = hwc->sample_period; |
ba3dd36c PZ |
7251 | event->attr.freq = 0; |
7252 | } | |
7253 | } | |
7254 | ||
b0a873eb PZ |
7255 | /* |
7256 | * Software event: cpu wall time clock | |
7257 | */ | |
7258 | ||
7259 | static void cpu_clock_event_update(struct perf_event *event) | |
24f1e32c | 7260 | { |
b0a873eb PZ |
7261 | s64 prev; |
7262 | u64 now; | |
7263 | ||
a4eaf7f1 | 7264 | now = local_clock(); |
b0a873eb PZ |
7265 | prev = local64_xchg(&event->hw.prev_count, now); |
7266 | local64_add(now - prev, &event->count); | |
24f1e32c | 7267 | } |
24f1e32c | 7268 | |
a4eaf7f1 | 7269 | static void cpu_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 7270 | { |
a4eaf7f1 | 7271 | local64_set(&event->hw.prev_count, local_clock()); |
b0a873eb | 7272 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
7273 | } |
7274 | ||
a4eaf7f1 | 7275 | static void cpu_clock_event_stop(struct perf_event *event, int flags) |
f29ac756 | 7276 | { |
b0a873eb PZ |
7277 | perf_swevent_cancel_hrtimer(event); |
7278 | cpu_clock_event_update(event); | |
7279 | } | |
f29ac756 | 7280 | |
a4eaf7f1 PZ |
7281 | static int cpu_clock_event_add(struct perf_event *event, int flags) |
7282 | { | |
7283 | if (flags & PERF_EF_START) | |
7284 | cpu_clock_event_start(event, flags); | |
6a694a60 | 7285 | perf_event_update_userpage(event); |
a4eaf7f1 PZ |
7286 | |
7287 | return 0; | |
7288 | } | |
7289 | ||
7290 | static void cpu_clock_event_del(struct perf_event *event, int flags) | |
7291 | { | |
7292 | cpu_clock_event_stop(event, flags); | |
7293 | } | |
7294 | ||
b0a873eb PZ |
7295 | static void cpu_clock_event_read(struct perf_event *event) |
7296 | { | |
7297 | cpu_clock_event_update(event); | |
7298 | } | |
f344011c | 7299 | |
b0a873eb PZ |
7300 | static int cpu_clock_event_init(struct perf_event *event) |
7301 | { | |
7302 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
7303 | return -ENOENT; | |
7304 | ||
7305 | if (event->attr.config != PERF_COUNT_SW_CPU_CLOCK) | |
7306 | return -ENOENT; | |
7307 | ||
2481c5fa SE |
7308 | /* |
7309 | * no branch sampling for software events | |
7310 | */ | |
7311 | if (has_branch_stack(event)) | |
7312 | return -EOPNOTSUPP; | |
7313 | ||
ba3dd36c PZ |
7314 | perf_swevent_init_hrtimer(event); |
7315 | ||
b0a873eb | 7316 | return 0; |
f29ac756 PZ |
7317 | } |
7318 | ||
b0a873eb | 7319 | static struct pmu perf_cpu_clock = { |
89a1e187 PZ |
7320 | .task_ctx_nr = perf_sw_context, |
7321 | ||
34f43927 PZ |
7322 | .capabilities = PERF_PMU_CAP_NO_NMI, |
7323 | ||
b0a873eb | 7324 | .event_init = cpu_clock_event_init, |
a4eaf7f1 PZ |
7325 | .add = cpu_clock_event_add, |
7326 | .del = cpu_clock_event_del, | |
7327 | .start = cpu_clock_event_start, | |
7328 | .stop = cpu_clock_event_stop, | |
b0a873eb PZ |
7329 | .read = cpu_clock_event_read, |
7330 | }; | |
7331 | ||
7332 | /* | |
7333 | * Software event: task time clock | |
7334 | */ | |
7335 | ||
7336 | static void task_clock_event_update(struct perf_event *event, u64 now) | |
5c92d124 | 7337 | { |
b0a873eb PZ |
7338 | u64 prev; |
7339 | s64 delta; | |
5c92d124 | 7340 | |
b0a873eb PZ |
7341 | prev = local64_xchg(&event->hw.prev_count, now); |
7342 | delta = now - prev; | |
7343 | local64_add(delta, &event->count); | |
7344 | } | |
5c92d124 | 7345 | |
a4eaf7f1 | 7346 | static void task_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 7347 | { |
a4eaf7f1 | 7348 | local64_set(&event->hw.prev_count, event->ctx->time); |
b0a873eb | 7349 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
7350 | } |
7351 | ||
a4eaf7f1 | 7352 | static void task_clock_event_stop(struct perf_event *event, int flags) |
b0a873eb PZ |
7353 | { |
7354 | perf_swevent_cancel_hrtimer(event); | |
7355 | task_clock_event_update(event, event->ctx->time); | |
a4eaf7f1 PZ |
7356 | } |
7357 | ||
7358 | static int task_clock_event_add(struct perf_event *event, int flags) | |
7359 | { | |
7360 | if (flags & PERF_EF_START) | |
7361 | task_clock_event_start(event, flags); | |
6a694a60 | 7362 | perf_event_update_userpage(event); |
b0a873eb | 7363 | |
a4eaf7f1 PZ |
7364 | return 0; |
7365 | } | |
7366 | ||
7367 | static void task_clock_event_del(struct perf_event *event, int flags) | |
7368 | { | |
7369 | task_clock_event_stop(event, PERF_EF_UPDATE); | |
b0a873eb PZ |
7370 | } |
7371 | ||
7372 | static void task_clock_event_read(struct perf_event *event) | |
7373 | { | |
768a06e2 PZ |
7374 | u64 now = perf_clock(); |
7375 | u64 delta = now - event->ctx->timestamp; | |
7376 | u64 time = event->ctx->time + delta; | |
b0a873eb PZ |
7377 | |
7378 | task_clock_event_update(event, time); | |
7379 | } | |
7380 | ||
7381 | static int task_clock_event_init(struct perf_event *event) | |
6fb2915d | 7382 | { |
b0a873eb PZ |
7383 | if (event->attr.type != PERF_TYPE_SOFTWARE) |
7384 | return -ENOENT; | |
7385 | ||
7386 | if (event->attr.config != PERF_COUNT_SW_TASK_CLOCK) | |
7387 | return -ENOENT; | |
7388 | ||
2481c5fa SE |
7389 | /* |
7390 | * no branch sampling for software events | |
7391 | */ | |
7392 | if (has_branch_stack(event)) | |
7393 | return -EOPNOTSUPP; | |
7394 | ||
ba3dd36c PZ |
7395 | perf_swevent_init_hrtimer(event); |
7396 | ||
b0a873eb | 7397 | return 0; |
6fb2915d LZ |
7398 | } |
7399 | ||
b0a873eb | 7400 | static struct pmu perf_task_clock = { |
89a1e187 PZ |
7401 | .task_ctx_nr = perf_sw_context, |
7402 | ||
34f43927 PZ |
7403 | .capabilities = PERF_PMU_CAP_NO_NMI, |
7404 | ||
b0a873eb | 7405 | .event_init = task_clock_event_init, |
a4eaf7f1 PZ |
7406 | .add = task_clock_event_add, |
7407 | .del = task_clock_event_del, | |
7408 | .start = task_clock_event_start, | |
7409 | .stop = task_clock_event_stop, | |
b0a873eb PZ |
7410 | .read = task_clock_event_read, |
7411 | }; | |
6fb2915d | 7412 | |
ad5133b7 | 7413 | static void perf_pmu_nop_void(struct pmu *pmu) |
e077df4f | 7414 | { |
e077df4f | 7415 | } |
6fb2915d | 7416 | |
fbbe0701 SB |
7417 | static void perf_pmu_nop_txn(struct pmu *pmu, unsigned int flags) |
7418 | { | |
7419 | } | |
7420 | ||
ad5133b7 | 7421 | static int perf_pmu_nop_int(struct pmu *pmu) |
6fb2915d | 7422 | { |
ad5133b7 | 7423 | return 0; |
6fb2915d LZ |
7424 | } |
7425 | ||
18ab2cd3 | 7426 | static DEFINE_PER_CPU(unsigned int, nop_txn_flags); |
fbbe0701 SB |
7427 | |
7428 | static void perf_pmu_start_txn(struct pmu *pmu, unsigned int flags) | |
6fb2915d | 7429 | { |
fbbe0701 SB |
7430 | __this_cpu_write(nop_txn_flags, flags); |
7431 | ||
7432 | if (flags & ~PERF_PMU_TXN_ADD) | |
7433 | return; | |
7434 | ||
ad5133b7 | 7435 | perf_pmu_disable(pmu); |
6fb2915d LZ |
7436 | } |
7437 | ||
ad5133b7 PZ |
7438 | static int perf_pmu_commit_txn(struct pmu *pmu) |
7439 | { | |
fbbe0701 SB |
7440 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
7441 | ||
7442 | __this_cpu_write(nop_txn_flags, 0); | |
7443 | ||
7444 | if (flags & ~PERF_PMU_TXN_ADD) | |
7445 | return 0; | |
7446 | ||
ad5133b7 PZ |
7447 | perf_pmu_enable(pmu); |
7448 | return 0; | |
7449 | } | |
e077df4f | 7450 | |
ad5133b7 | 7451 | static void perf_pmu_cancel_txn(struct pmu *pmu) |
24f1e32c | 7452 | { |
fbbe0701 SB |
7453 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
7454 | ||
7455 | __this_cpu_write(nop_txn_flags, 0); | |
7456 | ||
7457 | if (flags & ~PERF_PMU_TXN_ADD) | |
7458 | return; | |
7459 | ||
ad5133b7 | 7460 | perf_pmu_enable(pmu); |
24f1e32c FW |
7461 | } |
7462 | ||
35edc2a5 PZ |
7463 | static int perf_event_idx_default(struct perf_event *event) |
7464 | { | |
c719f560 | 7465 | return 0; |
35edc2a5 PZ |
7466 | } |
7467 | ||
8dc85d54 PZ |
7468 | /* |
7469 | * Ensures all contexts with the same task_ctx_nr have the same | |
7470 | * pmu_cpu_context too. | |
7471 | */ | |
9e317041 | 7472 | static struct perf_cpu_context __percpu *find_pmu_context(int ctxn) |
24f1e32c | 7473 | { |
8dc85d54 | 7474 | struct pmu *pmu; |
b326e956 | 7475 | |
8dc85d54 PZ |
7476 | if (ctxn < 0) |
7477 | return NULL; | |
24f1e32c | 7478 | |
8dc85d54 PZ |
7479 | list_for_each_entry(pmu, &pmus, entry) { |
7480 | if (pmu->task_ctx_nr == ctxn) | |
7481 | return pmu->pmu_cpu_context; | |
7482 | } | |
24f1e32c | 7483 | |
8dc85d54 | 7484 | return NULL; |
24f1e32c FW |
7485 | } |
7486 | ||
51676957 | 7487 | static void update_pmu_context(struct pmu *pmu, struct pmu *old_pmu) |
24f1e32c | 7488 | { |
51676957 PZ |
7489 | int cpu; |
7490 | ||
7491 | for_each_possible_cpu(cpu) { | |
7492 | struct perf_cpu_context *cpuctx; | |
7493 | ||
7494 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
7495 | ||
3f1f3320 PZ |
7496 | if (cpuctx->unique_pmu == old_pmu) |
7497 | cpuctx->unique_pmu = pmu; | |
51676957 PZ |
7498 | } |
7499 | } | |
7500 | ||
7501 | static void free_pmu_context(struct pmu *pmu) | |
7502 | { | |
7503 | struct pmu *i; | |
f5ffe02e | 7504 | |
8dc85d54 | 7505 | mutex_lock(&pmus_lock); |
0475f9ea | 7506 | /* |
8dc85d54 | 7507 | * Like a real lame refcount. |
0475f9ea | 7508 | */ |
51676957 PZ |
7509 | list_for_each_entry(i, &pmus, entry) { |
7510 | if (i->pmu_cpu_context == pmu->pmu_cpu_context) { | |
7511 | update_pmu_context(i, pmu); | |
8dc85d54 | 7512 | goto out; |
51676957 | 7513 | } |
8dc85d54 | 7514 | } |
d6d020e9 | 7515 | |
51676957 | 7516 | free_percpu(pmu->pmu_cpu_context); |
8dc85d54 PZ |
7517 | out: |
7518 | mutex_unlock(&pmus_lock); | |
24f1e32c | 7519 | } |
2e80a82a | 7520 | static struct idr pmu_idr; |
d6d020e9 | 7521 | |
abe43400 PZ |
7522 | static ssize_t |
7523 | type_show(struct device *dev, struct device_attribute *attr, char *page) | |
7524 | { | |
7525 | struct pmu *pmu = dev_get_drvdata(dev); | |
7526 | ||
7527 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->type); | |
7528 | } | |
90826ca7 | 7529 | static DEVICE_ATTR_RO(type); |
abe43400 | 7530 | |
62b85639 SE |
7531 | static ssize_t |
7532 | perf_event_mux_interval_ms_show(struct device *dev, | |
7533 | struct device_attribute *attr, | |
7534 | char *page) | |
7535 | { | |
7536 | struct pmu *pmu = dev_get_drvdata(dev); | |
7537 | ||
7538 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->hrtimer_interval_ms); | |
7539 | } | |
7540 | ||
272325c4 PZ |
7541 | static DEFINE_MUTEX(mux_interval_mutex); |
7542 | ||
62b85639 SE |
7543 | static ssize_t |
7544 | perf_event_mux_interval_ms_store(struct device *dev, | |
7545 | struct device_attribute *attr, | |
7546 | const char *buf, size_t count) | |
7547 | { | |
7548 | struct pmu *pmu = dev_get_drvdata(dev); | |
7549 | int timer, cpu, ret; | |
7550 | ||
7551 | ret = kstrtoint(buf, 0, &timer); | |
7552 | if (ret) | |
7553 | return ret; | |
7554 | ||
7555 | if (timer < 1) | |
7556 | return -EINVAL; | |
7557 | ||
7558 | /* same value, noting to do */ | |
7559 | if (timer == pmu->hrtimer_interval_ms) | |
7560 | return count; | |
7561 | ||
272325c4 | 7562 | mutex_lock(&mux_interval_mutex); |
62b85639 SE |
7563 | pmu->hrtimer_interval_ms = timer; |
7564 | ||
7565 | /* update all cpuctx for this PMU */ | |
272325c4 PZ |
7566 | get_online_cpus(); |
7567 | for_each_online_cpu(cpu) { | |
62b85639 SE |
7568 | struct perf_cpu_context *cpuctx; |
7569 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
7570 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * timer); | |
7571 | ||
272325c4 PZ |
7572 | cpu_function_call(cpu, |
7573 | (remote_function_f)perf_mux_hrtimer_restart, cpuctx); | |
62b85639 | 7574 | } |
272325c4 PZ |
7575 | put_online_cpus(); |
7576 | mutex_unlock(&mux_interval_mutex); | |
62b85639 SE |
7577 | |
7578 | return count; | |
7579 | } | |
90826ca7 | 7580 | static DEVICE_ATTR_RW(perf_event_mux_interval_ms); |
62b85639 | 7581 | |
90826ca7 GKH |
7582 | static struct attribute *pmu_dev_attrs[] = { |
7583 | &dev_attr_type.attr, | |
7584 | &dev_attr_perf_event_mux_interval_ms.attr, | |
7585 | NULL, | |
abe43400 | 7586 | }; |
90826ca7 | 7587 | ATTRIBUTE_GROUPS(pmu_dev); |
abe43400 PZ |
7588 | |
7589 | static int pmu_bus_running; | |
7590 | static struct bus_type pmu_bus = { | |
7591 | .name = "event_source", | |
90826ca7 | 7592 | .dev_groups = pmu_dev_groups, |
abe43400 PZ |
7593 | }; |
7594 | ||
7595 | static void pmu_dev_release(struct device *dev) | |
7596 | { | |
7597 | kfree(dev); | |
7598 | } | |
7599 | ||
7600 | static int pmu_dev_alloc(struct pmu *pmu) | |
7601 | { | |
7602 | int ret = -ENOMEM; | |
7603 | ||
7604 | pmu->dev = kzalloc(sizeof(struct device), GFP_KERNEL); | |
7605 | if (!pmu->dev) | |
7606 | goto out; | |
7607 | ||
0c9d42ed | 7608 | pmu->dev->groups = pmu->attr_groups; |
abe43400 PZ |
7609 | device_initialize(pmu->dev); |
7610 | ret = dev_set_name(pmu->dev, "%s", pmu->name); | |
7611 | if (ret) | |
7612 | goto free_dev; | |
7613 | ||
7614 | dev_set_drvdata(pmu->dev, pmu); | |
7615 | pmu->dev->bus = &pmu_bus; | |
7616 | pmu->dev->release = pmu_dev_release; | |
7617 | ret = device_add(pmu->dev); | |
7618 | if (ret) | |
7619 | goto free_dev; | |
7620 | ||
7621 | out: | |
7622 | return ret; | |
7623 | ||
7624 | free_dev: | |
7625 | put_device(pmu->dev); | |
7626 | goto out; | |
7627 | } | |
7628 | ||
547e9fd7 | 7629 | static struct lock_class_key cpuctx_mutex; |
facc4307 | 7630 | static struct lock_class_key cpuctx_lock; |
547e9fd7 | 7631 | |
03d8e80b | 7632 | int perf_pmu_register(struct pmu *pmu, const char *name, int type) |
24f1e32c | 7633 | { |
108b02cf | 7634 | int cpu, ret; |
24f1e32c | 7635 | |
b0a873eb | 7636 | mutex_lock(&pmus_lock); |
33696fc0 PZ |
7637 | ret = -ENOMEM; |
7638 | pmu->pmu_disable_count = alloc_percpu(int); | |
7639 | if (!pmu->pmu_disable_count) | |
7640 | goto unlock; | |
f29ac756 | 7641 | |
2e80a82a PZ |
7642 | pmu->type = -1; |
7643 | if (!name) | |
7644 | goto skip_type; | |
7645 | pmu->name = name; | |
7646 | ||
7647 | if (type < 0) { | |
0e9c3be2 TH |
7648 | type = idr_alloc(&pmu_idr, pmu, PERF_TYPE_MAX, 0, GFP_KERNEL); |
7649 | if (type < 0) { | |
7650 | ret = type; | |
2e80a82a PZ |
7651 | goto free_pdc; |
7652 | } | |
7653 | } | |
7654 | pmu->type = type; | |
7655 | ||
abe43400 PZ |
7656 | if (pmu_bus_running) { |
7657 | ret = pmu_dev_alloc(pmu); | |
7658 | if (ret) | |
7659 | goto free_idr; | |
7660 | } | |
7661 | ||
2e80a82a | 7662 | skip_type: |
8dc85d54 PZ |
7663 | pmu->pmu_cpu_context = find_pmu_context(pmu->task_ctx_nr); |
7664 | if (pmu->pmu_cpu_context) | |
7665 | goto got_cpu_context; | |
f29ac756 | 7666 | |
c4814202 | 7667 | ret = -ENOMEM; |
108b02cf PZ |
7668 | pmu->pmu_cpu_context = alloc_percpu(struct perf_cpu_context); |
7669 | if (!pmu->pmu_cpu_context) | |
abe43400 | 7670 | goto free_dev; |
f344011c | 7671 | |
108b02cf PZ |
7672 | for_each_possible_cpu(cpu) { |
7673 | struct perf_cpu_context *cpuctx; | |
7674 | ||
7675 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
eb184479 | 7676 | __perf_event_init_context(&cpuctx->ctx); |
547e9fd7 | 7677 | lockdep_set_class(&cpuctx->ctx.mutex, &cpuctx_mutex); |
facc4307 | 7678 | lockdep_set_class(&cpuctx->ctx.lock, &cpuctx_lock); |
108b02cf | 7679 | cpuctx->ctx.pmu = pmu; |
9e630205 | 7680 | |
272325c4 | 7681 | __perf_mux_hrtimer_init(cpuctx, cpu); |
9e630205 | 7682 | |
3f1f3320 | 7683 | cpuctx->unique_pmu = pmu; |
108b02cf | 7684 | } |
76e1d904 | 7685 | |
8dc85d54 | 7686 | got_cpu_context: |
ad5133b7 PZ |
7687 | if (!pmu->start_txn) { |
7688 | if (pmu->pmu_enable) { | |
7689 | /* | |
7690 | * If we have pmu_enable/pmu_disable calls, install | |
7691 | * transaction stubs that use that to try and batch | |
7692 | * hardware accesses. | |
7693 | */ | |
7694 | pmu->start_txn = perf_pmu_start_txn; | |
7695 | pmu->commit_txn = perf_pmu_commit_txn; | |
7696 | pmu->cancel_txn = perf_pmu_cancel_txn; | |
7697 | } else { | |
fbbe0701 | 7698 | pmu->start_txn = perf_pmu_nop_txn; |
ad5133b7 PZ |
7699 | pmu->commit_txn = perf_pmu_nop_int; |
7700 | pmu->cancel_txn = perf_pmu_nop_void; | |
f344011c | 7701 | } |
5c92d124 | 7702 | } |
15dbf27c | 7703 | |
ad5133b7 PZ |
7704 | if (!pmu->pmu_enable) { |
7705 | pmu->pmu_enable = perf_pmu_nop_void; | |
7706 | pmu->pmu_disable = perf_pmu_nop_void; | |
7707 | } | |
7708 | ||
35edc2a5 PZ |
7709 | if (!pmu->event_idx) |
7710 | pmu->event_idx = perf_event_idx_default; | |
7711 | ||
b0a873eb | 7712 | list_add_rcu(&pmu->entry, &pmus); |
bed5b25a | 7713 | atomic_set(&pmu->exclusive_cnt, 0); |
33696fc0 PZ |
7714 | ret = 0; |
7715 | unlock: | |
b0a873eb PZ |
7716 | mutex_unlock(&pmus_lock); |
7717 | ||
33696fc0 | 7718 | return ret; |
108b02cf | 7719 | |
abe43400 PZ |
7720 | free_dev: |
7721 | device_del(pmu->dev); | |
7722 | put_device(pmu->dev); | |
7723 | ||
2e80a82a PZ |
7724 | free_idr: |
7725 | if (pmu->type >= PERF_TYPE_MAX) | |
7726 | idr_remove(&pmu_idr, pmu->type); | |
7727 | ||
108b02cf PZ |
7728 | free_pdc: |
7729 | free_percpu(pmu->pmu_disable_count); | |
7730 | goto unlock; | |
f29ac756 | 7731 | } |
c464c76e | 7732 | EXPORT_SYMBOL_GPL(perf_pmu_register); |
f29ac756 | 7733 | |
b0a873eb | 7734 | void perf_pmu_unregister(struct pmu *pmu) |
5c92d124 | 7735 | { |
b0a873eb PZ |
7736 | mutex_lock(&pmus_lock); |
7737 | list_del_rcu(&pmu->entry); | |
7738 | mutex_unlock(&pmus_lock); | |
5c92d124 | 7739 | |
0475f9ea | 7740 | /* |
cde8e884 PZ |
7741 | * We dereference the pmu list under both SRCU and regular RCU, so |
7742 | * synchronize against both of those. | |
0475f9ea | 7743 | */ |
b0a873eb | 7744 | synchronize_srcu(&pmus_srcu); |
cde8e884 | 7745 | synchronize_rcu(); |
d6d020e9 | 7746 | |
33696fc0 | 7747 | free_percpu(pmu->pmu_disable_count); |
2e80a82a PZ |
7748 | if (pmu->type >= PERF_TYPE_MAX) |
7749 | idr_remove(&pmu_idr, pmu->type); | |
abe43400 PZ |
7750 | device_del(pmu->dev); |
7751 | put_device(pmu->dev); | |
51676957 | 7752 | free_pmu_context(pmu); |
b0a873eb | 7753 | } |
c464c76e | 7754 | EXPORT_SYMBOL_GPL(perf_pmu_unregister); |
d6d020e9 | 7755 | |
cc34b98b MR |
7756 | static int perf_try_init_event(struct pmu *pmu, struct perf_event *event) |
7757 | { | |
ccd41c86 | 7758 | struct perf_event_context *ctx = NULL; |
cc34b98b MR |
7759 | int ret; |
7760 | ||
7761 | if (!try_module_get(pmu->module)) | |
7762 | return -ENODEV; | |
ccd41c86 PZ |
7763 | |
7764 | if (event->group_leader != event) { | |
8b10c5e2 PZ |
7765 | /* |
7766 | * This ctx->mutex can nest when we're called through | |
7767 | * inheritance. See the perf_event_ctx_lock_nested() comment. | |
7768 | */ | |
7769 | ctx = perf_event_ctx_lock_nested(event->group_leader, | |
7770 | SINGLE_DEPTH_NESTING); | |
ccd41c86 PZ |
7771 | BUG_ON(!ctx); |
7772 | } | |
7773 | ||
cc34b98b MR |
7774 | event->pmu = pmu; |
7775 | ret = pmu->event_init(event); | |
ccd41c86 PZ |
7776 | |
7777 | if (ctx) | |
7778 | perf_event_ctx_unlock(event->group_leader, ctx); | |
7779 | ||
cc34b98b MR |
7780 | if (ret) |
7781 | module_put(pmu->module); | |
7782 | ||
7783 | return ret; | |
7784 | } | |
7785 | ||
18ab2cd3 | 7786 | static struct pmu *perf_init_event(struct perf_event *event) |
b0a873eb PZ |
7787 | { |
7788 | struct pmu *pmu = NULL; | |
7789 | int idx; | |
940c5b29 | 7790 | int ret; |
b0a873eb PZ |
7791 | |
7792 | idx = srcu_read_lock(&pmus_srcu); | |
2e80a82a PZ |
7793 | |
7794 | rcu_read_lock(); | |
7795 | pmu = idr_find(&pmu_idr, event->attr.type); | |
7796 | rcu_read_unlock(); | |
940c5b29 | 7797 | if (pmu) { |
cc34b98b | 7798 | ret = perf_try_init_event(pmu, event); |
940c5b29 LM |
7799 | if (ret) |
7800 | pmu = ERR_PTR(ret); | |
2e80a82a | 7801 | goto unlock; |
940c5b29 | 7802 | } |
2e80a82a | 7803 | |
b0a873eb | 7804 | list_for_each_entry_rcu(pmu, &pmus, entry) { |
cc34b98b | 7805 | ret = perf_try_init_event(pmu, event); |
b0a873eb | 7806 | if (!ret) |
e5f4d339 | 7807 | goto unlock; |
76e1d904 | 7808 | |
b0a873eb PZ |
7809 | if (ret != -ENOENT) { |
7810 | pmu = ERR_PTR(ret); | |
e5f4d339 | 7811 | goto unlock; |
f344011c | 7812 | } |
5c92d124 | 7813 | } |
e5f4d339 PZ |
7814 | pmu = ERR_PTR(-ENOENT); |
7815 | unlock: | |
b0a873eb | 7816 | srcu_read_unlock(&pmus_srcu, idx); |
15dbf27c | 7817 | |
4aeb0b42 | 7818 | return pmu; |
5c92d124 IM |
7819 | } |
7820 | ||
4beb31f3 FW |
7821 | static void account_event_cpu(struct perf_event *event, int cpu) |
7822 | { | |
7823 | if (event->parent) | |
7824 | return; | |
7825 | ||
4beb31f3 FW |
7826 | if (is_cgroup_event(event)) |
7827 | atomic_inc(&per_cpu(perf_cgroup_events, cpu)); | |
7828 | } | |
7829 | ||
555e0c1e FW |
7830 | /* Freq events need the tick to stay alive (see perf_event_task_tick). */ |
7831 | static void account_freq_event_nohz(void) | |
7832 | { | |
7833 | #ifdef CONFIG_NO_HZ_FULL | |
7834 | /* Lock so we don't race with concurrent unaccount */ | |
7835 | spin_lock(&nr_freq_lock); | |
7836 | if (atomic_inc_return(&nr_freq_events) == 1) | |
7837 | tick_nohz_dep_set(TICK_DEP_BIT_PERF_EVENTS); | |
7838 | spin_unlock(&nr_freq_lock); | |
7839 | #endif | |
7840 | } | |
7841 | ||
7842 | static void account_freq_event(void) | |
7843 | { | |
7844 | if (tick_nohz_full_enabled()) | |
7845 | account_freq_event_nohz(); | |
7846 | else | |
7847 | atomic_inc(&nr_freq_events); | |
7848 | } | |
7849 | ||
7850 | ||
766d6c07 FW |
7851 | static void account_event(struct perf_event *event) |
7852 | { | |
25432ae9 PZ |
7853 | bool inc = false; |
7854 | ||
4beb31f3 FW |
7855 | if (event->parent) |
7856 | return; | |
7857 | ||
766d6c07 | 7858 | if (event->attach_state & PERF_ATTACH_TASK) |
25432ae9 | 7859 | inc = true; |
766d6c07 FW |
7860 | if (event->attr.mmap || event->attr.mmap_data) |
7861 | atomic_inc(&nr_mmap_events); | |
7862 | if (event->attr.comm) | |
7863 | atomic_inc(&nr_comm_events); | |
7864 | if (event->attr.task) | |
7865 | atomic_inc(&nr_task_events); | |
555e0c1e FW |
7866 | if (event->attr.freq) |
7867 | account_freq_event(); | |
45ac1403 AH |
7868 | if (event->attr.context_switch) { |
7869 | atomic_inc(&nr_switch_events); | |
25432ae9 | 7870 | inc = true; |
45ac1403 | 7871 | } |
4beb31f3 | 7872 | if (has_branch_stack(event)) |
25432ae9 | 7873 | inc = true; |
4beb31f3 | 7874 | if (is_cgroup_event(event)) |
25432ae9 PZ |
7875 | inc = true; |
7876 | ||
9107c89e PZ |
7877 | if (inc) { |
7878 | if (atomic_inc_not_zero(&perf_sched_count)) | |
7879 | goto enabled; | |
7880 | ||
7881 | mutex_lock(&perf_sched_mutex); | |
7882 | if (!atomic_read(&perf_sched_count)) { | |
7883 | static_branch_enable(&perf_sched_events); | |
7884 | /* | |
7885 | * Guarantee that all CPUs observe they key change and | |
7886 | * call the perf scheduling hooks before proceeding to | |
7887 | * install events that need them. | |
7888 | */ | |
7889 | synchronize_sched(); | |
7890 | } | |
7891 | /* | |
7892 | * Now that we have waited for the sync_sched(), allow further | |
7893 | * increments to by-pass the mutex. | |
7894 | */ | |
7895 | atomic_inc(&perf_sched_count); | |
7896 | mutex_unlock(&perf_sched_mutex); | |
7897 | } | |
7898 | enabled: | |
4beb31f3 FW |
7899 | |
7900 | account_event_cpu(event, event->cpu); | |
766d6c07 FW |
7901 | } |
7902 | ||
0793a61d | 7903 | /* |
cdd6c482 | 7904 | * Allocate and initialize a event structure |
0793a61d | 7905 | */ |
cdd6c482 | 7906 | static struct perf_event * |
c3f00c70 | 7907 | perf_event_alloc(struct perf_event_attr *attr, int cpu, |
d580ff86 PZ |
7908 | struct task_struct *task, |
7909 | struct perf_event *group_leader, | |
7910 | struct perf_event *parent_event, | |
4dc0da86 | 7911 | perf_overflow_handler_t overflow_handler, |
79dff51e | 7912 | void *context, int cgroup_fd) |
0793a61d | 7913 | { |
51b0fe39 | 7914 | struct pmu *pmu; |
cdd6c482 IM |
7915 | struct perf_event *event; |
7916 | struct hw_perf_event *hwc; | |
90983b16 | 7917 | long err = -EINVAL; |
0793a61d | 7918 | |
66832eb4 ON |
7919 | if ((unsigned)cpu >= nr_cpu_ids) { |
7920 | if (!task || cpu != -1) | |
7921 | return ERR_PTR(-EINVAL); | |
7922 | } | |
7923 | ||
c3f00c70 | 7924 | event = kzalloc(sizeof(*event), GFP_KERNEL); |
cdd6c482 | 7925 | if (!event) |
d5d2bc0d | 7926 | return ERR_PTR(-ENOMEM); |
0793a61d | 7927 | |
04289bb9 | 7928 | /* |
cdd6c482 | 7929 | * Single events are their own group leaders, with an |
04289bb9 IM |
7930 | * empty sibling list: |
7931 | */ | |
7932 | if (!group_leader) | |
cdd6c482 | 7933 | group_leader = event; |
04289bb9 | 7934 | |
cdd6c482 IM |
7935 | mutex_init(&event->child_mutex); |
7936 | INIT_LIST_HEAD(&event->child_list); | |
fccc714b | 7937 | |
cdd6c482 IM |
7938 | INIT_LIST_HEAD(&event->group_entry); |
7939 | INIT_LIST_HEAD(&event->event_entry); | |
7940 | INIT_LIST_HEAD(&event->sibling_list); | |
10c6db11 | 7941 | INIT_LIST_HEAD(&event->rb_entry); |
71ad88ef | 7942 | INIT_LIST_HEAD(&event->active_entry); |
f3ae75de SE |
7943 | INIT_HLIST_NODE(&event->hlist_entry); |
7944 | ||
10c6db11 | 7945 | |
cdd6c482 | 7946 | init_waitqueue_head(&event->waitq); |
e360adbe | 7947 | init_irq_work(&event->pending, perf_pending_event); |
0793a61d | 7948 | |
cdd6c482 | 7949 | mutex_init(&event->mmap_mutex); |
7b732a75 | 7950 | |
a6fa941d | 7951 | atomic_long_set(&event->refcount, 1); |
cdd6c482 IM |
7952 | event->cpu = cpu; |
7953 | event->attr = *attr; | |
7954 | event->group_leader = group_leader; | |
7955 | event->pmu = NULL; | |
cdd6c482 | 7956 | event->oncpu = -1; |
a96bbc16 | 7957 | |
cdd6c482 | 7958 | event->parent = parent_event; |
b84fbc9f | 7959 | |
17cf22c3 | 7960 | event->ns = get_pid_ns(task_active_pid_ns(current)); |
cdd6c482 | 7961 | event->id = atomic64_inc_return(&perf_event_id); |
a96bbc16 | 7962 | |
cdd6c482 | 7963 | event->state = PERF_EVENT_STATE_INACTIVE; |
329d876d | 7964 | |
d580ff86 PZ |
7965 | if (task) { |
7966 | event->attach_state = PERF_ATTACH_TASK; | |
d580ff86 | 7967 | /* |
50f16a8b PZ |
7968 | * XXX pmu::event_init needs to know what task to account to |
7969 | * and we cannot use the ctx information because we need the | |
7970 | * pmu before we get a ctx. | |
d580ff86 | 7971 | */ |
50f16a8b | 7972 | event->hw.target = task; |
d580ff86 PZ |
7973 | } |
7974 | ||
34f43927 PZ |
7975 | event->clock = &local_clock; |
7976 | if (parent_event) | |
7977 | event->clock = parent_event->clock; | |
7978 | ||
4dc0da86 | 7979 | if (!overflow_handler && parent_event) { |
b326e956 | 7980 | overflow_handler = parent_event->overflow_handler; |
4dc0da86 AK |
7981 | context = parent_event->overflow_handler_context; |
7982 | } | |
66832eb4 | 7983 | |
b326e956 | 7984 | event->overflow_handler = overflow_handler; |
4dc0da86 | 7985 | event->overflow_handler_context = context; |
97eaf530 | 7986 | |
0231bb53 | 7987 | perf_event__state_init(event); |
a86ed508 | 7988 | |
4aeb0b42 | 7989 | pmu = NULL; |
b8e83514 | 7990 | |
cdd6c482 | 7991 | hwc = &event->hw; |
bd2b5b12 | 7992 | hwc->sample_period = attr->sample_period; |
0d48696f | 7993 | if (attr->freq && attr->sample_freq) |
bd2b5b12 | 7994 | hwc->sample_period = 1; |
eced1dfc | 7995 | hwc->last_period = hwc->sample_period; |
bd2b5b12 | 7996 | |
e7850595 | 7997 | local64_set(&hwc->period_left, hwc->sample_period); |
60db5e09 | 7998 | |
2023b359 | 7999 | /* |
cdd6c482 | 8000 | * we currently do not support PERF_FORMAT_GROUP on inherited events |
2023b359 | 8001 | */ |
3dab77fb | 8002 | if (attr->inherit && (attr->read_format & PERF_FORMAT_GROUP)) |
90983b16 | 8003 | goto err_ns; |
a46a2300 YZ |
8004 | |
8005 | if (!has_branch_stack(event)) | |
8006 | event->attr.branch_sample_type = 0; | |
2023b359 | 8007 | |
79dff51e MF |
8008 | if (cgroup_fd != -1) { |
8009 | err = perf_cgroup_connect(cgroup_fd, event, attr, group_leader); | |
8010 | if (err) | |
8011 | goto err_ns; | |
8012 | } | |
8013 | ||
b0a873eb | 8014 | pmu = perf_init_event(event); |
4aeb0b42 | 8015 | if (!pmu) |
90983b16 FW |
8016 | goto err_ns; |
8017 | else if (IS_ERR(pmu)) { | |
4aeb0b42 | 8018 | err = PTR_ERR(pmu); |
90983b16 | 8019 | goto err_ns; |
621a01ea | 8020 | } |
d5d2bc0d | 8021 | |
bed5b25a AS |
8022 | err = exclusive_event_init(event); |
8023 | if (err) | |
8024 | goto err_pmu; | |
8025 | ||
cdd6c482 | 8026 | if (!event->parent) { |
927c7a9e FW |
8027 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) { |
8028 | err = get_callchain_buffers(); | |
90983b16 | 8029 | if (err) |
bed5b25a | 8030 | goto err_per_task; |
d010b332 | 8031 | } |
f344011c | 8032 | } |
9ee318a7 | 8033 | |
927a5570 AS |
8034 | /* symmetric to unaccount_event() in _free_event() */ |
8035 | account_event(event); | |
8036 | ||
cdd6c482 | 8037 | return event; |
90983b16 | 8038 | |
bed5b25a AS |
8039 | err_per_task: |
8040 | exclusive_event_destroy(event); | |
8041 | ||
90983b16 FW |
8042 | err_pmu: |
8043 | if (event->destroy) | |
8044 | event->destroy(event); | |
c464c76e | 8045 | module_put(pmu->module); |
90983b16 | 8046 | err_ns: |
79dff51e MF |
8047 | if (is_cgroup_event(event)) |
8048 | perf_detach_cgroup(event); | |
90983b16 FW |
8049 | if (event->ns) |
8050 | put_pid_ns(event->ns); | |
8051 | kfree(event); | |
8052 | ||
8053 | return ERR_PTR(err); | |
0793a61d TG |
8054 | } |
8055 | ||
cdd6c482 IM |
8056 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
8057 | struct perf_event_attr *attr) | |
974802ea | 8058 | { |
974802ea | 8059 | u32 size; |
cdf8073d | 8060 | int ret; |
974802ea PZ |
8061 | |
8062 | if (!access_ok(VERIFY_WRITE, uattr, PERF_ATTR_SIZE_VER0)) | |
8063 | return -EFAULT; | |
8064 | ||
8065 | /* | |
8066 | * zero the full structure, so that a short copy will be nice. | |
8067 | */ | |
8068 | memset(attr, 0, sizeof(*attr)); | |
8069 | ||
8070 | ret = get_user(size, &uattr->size); | |
8071 | if (ret) | |
8072 | return ret; | |
8073 | ||
8074 | if (size > PAGE_SIZE) /* silly large */ | |
8075 | goto err_size; | |
8076 | ||
8077 | if (!size) /* abi compat */ | |
8078 | size = PERF_ATTR_SIZE_VER0; | |
8079 | ||
8080 | if (size < PERF_ATTR_SIZE_VER0) | |
8081 | goto err_size; | |
8082 | ||
8083 | /* | |
8084 | * If we're handed a bigger struct than we know of, | |
cdf8073d IS |
8085 | * ensure all the unknown bits are 0 - i.e. new |
8086 | * user-space does not rely on any kernel feature | |
8087 | * extensions we dont know about yet. | |
974802ea PZ |
8088 | */ |
8089 | if (size > sizeof(*attr)) { | |
cdf8073d IS |
8090 | unsigned char __user *addr; |
8091 | unsigned char __user *end; | |
8092 | unsigned char val; | |
974802ea | 8093 | |
cdf8073d IS |
8094 | addr = (void __user *)uattr + sizeof(*attr); |
8095 | end = (void __user *)uattr + size; | |
974802ea | 8096 | |
cdf8073d | 8097 | for (; addr < end; addr++) { |
974802ea PZ |
8098 | ret = get_user(val, addr); |
8099 | if (ret) | |
8100 | return ret; | |
8101 | if (val) | |
8102 | goto err_size; | |
8103 | } | |
b3e62e35 | 8104 | size = sizeof(*attr); |
974802ea PZ |
8105 | } |
8106 | ||
8107 | ret = copy_from_user(attr, uattr, size); | |
8108 | if (ret) | |
8109 | return -EFAULT; | |
8110 | ||
cd757645 | 8111 | if (attr->__reserved_1) |
974802ea PZ |
8112 | return -EINVAL; |
8113 | ||
8114 | if (attr->sample_type & ~(PERF_SAMPLE_MAX-1)) | |
8115 | return -EINVAL; | |
8116 | ||
8117 | if (attr->read_format & ~(PERF_FORMAT_MAX-1)) | |
8118 | return -EINVAL; | |
8119 | ||
bce38cd5 SE |
8120 | if (attr->sample_type & PERF_SAMPLE_BRANCH_STACK) { |
8121 | u64 mask = attr->branch_sample_type; | |
8122 | ||
8123 | /* only using defined bits */ | |
8124 | if (mask & ~(PERF_SAMPLE_BRANCH_MAX-1)) | |
8125 | return -EINVAL; | |
8126 | ||
8127 | /* at least one branch bit must be set */ | |
8128 | if (!(mask & ~PERF_SAMPLE_BRANCH_PLM_ALL)) | |
8129 | return -EINVAL; | |
8130 | ||
bce38cd5 SE |
8131 | /* propagate priv level, when not set for branch */ |
8132 | if (!(mask & PERF_SAMPLE_BRANCH_PLM_ALL)) { | |
8133 | ||
8134 | /* exclude_kernel checked on syscall entry */ | |
8135 | if (!attr->exclude_kernel) | |
8136 | mask |= PERF_SAMPLE_BRANCH_KERNEL; | |
8137 | ||
8138 | if (!attr->exclude_user) | |
8139 | mask |= PERF_SAMPLE_BRANCH_USER; | |
8140 | ||
8141 | if (!attr->exclude_hv) | |
8142 | mask |= PERF_SAMPLE_BRANCH_HV; | |
8143 | /* | |
8144 | * adjust user setting (for HW filter setup) | |
8145 | */ | |
8146 | attr->branch_sample_type = mask; | |
8147 | } | |
e712209a SE |
8148 | /* privileged levels capture (kernel, hv): check permissions */ |
8149 | if ((mask & PERF_SAMPLE_BRANCH_PERM_PLM) | |
2b923c8f SE |
8150 | && perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) |
8151 | return -EACCES; | |
bce38cd5 | 8152 | } |
4018994f | 8153 | |
c5ebcedb | 8154 | if (attr->sample_type & PERF_SAMPLE_REGS_USER) { |
4018994f | 8155 | ret = perf_reg_validate(attr->sample_regs_user); |
c5ebcedb JO |
8156 | if (ret) |
8157 | return ret; | |
8158 | } | |
8159 | ||
8160 | if (attr->sample_type & PERF_SAMPLE_STACK_USER) { | |
8161 | if (!arch_perf_have_user_stack_dump()) | |
8162 | return -ENOSYS; | |
8163 | ||
8164 | /* | |
8165 | * We have __u32 type for the size, but so far | |
8166 | * we can only use __u16 as maximum due to the | |
8167 | * __u16 sample size limit. | |
8168 | */ | |
8169 | if (attr->sample_stack_user >= USHRT_MAX) | |
8170 | ret = -EINVAL; | |
8171 | else if (!IS_ALIGNED(attr->sample_stack_user, sizeof(u64))) | |
8172 | ret = -EINVAL; | |
8173 | } | |
4018994f | 8174 | |
60e2364e SE |
8175 | if (attr->sample_type & PERF_SAMPLE_REGS_INTR) |
8176 | ret = perf_reg_validate(attr->sample_regs_intr); | |
974802ea PZ |
8177 | out: |
8178 | return ret; | |
8179 | ||
8180 | err_size: | |
8181 | put_user(sizeof(*attr), &uattr->size); | |
8182 | ret = -E2BIG; | |
8183 | goto out; | |
8184 | } | |
8185 | ||
ac9721f3 PZ |
8186 | static int |
8187 | perf_event_set_output(struct perf_event *event, struct perf_event *output_event) | |
a4be7c27 | 8188 | { |
b69cf536 | 8189 | struct ring_buffer *rb = NULL; |
a4be7c27 PZ |
8190 | int ret = -EINVAL; |
8191 | ||
ac9721f3 | 8192 | if (!output_event) |
a4be7c27 PZ |
8193 | goto set; |
8194 | ||
ac9721f3 PZ |
8195 | /* don't allow circular references */ |
8196 | if (event == output_event) | |
a4be7c27 PZ |
8197 | goto out; |
8198 | ||
0f139300 PZ |
8199 | /* |
8200 | * Don't allow cross-cpu buffers | |
8201 | */ | |
8202 | if (output_event->cpu != event->cpu) | |
8203 | goto out; | |
8204 | ||
8205 | /* | |
76369139 | 8206 | * If its not a per-cpu rb, it must be the same task. |
0f139300 PZ |
8207 | */ |
8208 | if (output_event->cpu == -1 && output_event->ctx != event->ctx) | |
8209 | goto out; | |
8210 | ||
34f43927 PZ |
8211 | /* |
8212 | * Mixing clocks in the same buffer is trouble you don't need. | |
8213 | */ | |
8214 | if (output_event->clock != event->clock) | |
8215 | goto out; | |
8216 | ||
45bfb2e5 PZ |
8217 | /* |
8218 | * If both events generate aux data, they must be on the same PMU | |
8219 | */ | |
8220 | if (has_aux(event) && has_aux(output_event) && | |
8221 | event->pmu != output_event->pmu) | |
8222 | goto out; | |
8223 | ||
a4be7c27 | 8224 | set: |
cdd6c482 | 8225 | mutex_lock(&event->mmap_mutex); |
ac9721f3 PZ |
8226 | /* Can't redirect output if we've got an active mmap() */ |
8227 | if (atomic_read(&event->mmap_count)) | |
8228 | goto unlock; | |
a4be7c27 | 8229 | |
ac9721f3 | 8230 | if (output_event) { |
76369139 FW |
8231 | /* get the rb we want to redirect to */ |
8232 | rb = ring_buffer_get(output_event); | |
8233 | if (!rb) | |
ac9721f3 | 8234 | goto unlock; |
a4be7c27 PZ |
8235 | } |
8236 | ||
b69cf536 | 8237 | ring_buffer_attach(event, rb); |
9bb5d40c | 8238 | |
a4be7c27 | 8239 | ret = 0; |
ac9721f3 PZ |
8240 | unlock: |
8241 | mutex_unlock(&event->mmap_mutex); | |
8242 | ||
a4be7c27 | 8243 | out: |
a4be7c27 PZ |
8244 | return ret; |
8245 | } | |
8246 | ||
f63a8daa PZ |
8247 | static void mutex_lock_double(struct mutex *a, struct mutex *b) |
8248 | { | |
8249 | if (b < a) | |
8250 | swap(a, b); | |
8251 | ||
8252 | mutex_lock(a); | |
8253 | mutex_lock_nested(b, SINGLE_DEPTH_NESTING); | |
8254 | } | |
8255 | ||
34f43927 PZ |
8256 | static int perf_event_set_clock(struct perf_event *event, clockid_t clk_id) |
8257 | { | |
8258 | bool nmi_safe = false; | |
8259 | ||
8260 | switch (clk_id) { | |
8261 | case CLOCK_MONOTONIC: | |
8262 | event->clock = &ktime_get_mono_fast_ns; | |
8263 | nmi_safe = true; | |
8264 | break; | |
8265 | ||
8266 | case CLOCK_MONOTONIC_RAW: | |
8267 | event->clock = &ktime_get_raw_fast_ns; | |
8268 | nmi_safe = true; | |
8269 | break; | |
8270 | ||
8271 | case CLOCK_REALTIME: | |
8272 | event->clock = &ktime_get_real_ns; | |
8273 | break; | |
8274 | ||
8275 | case CLOCK_BOOTTIME: | |
8276 | event->clock = &ktime_get_boot_ns; | |
8277 | break; | |
8278 | ||
8279 | case CLOCK_TAI: | |
8280 | event->clock = &ktime_get_tai_ns; | |
8281 | break; | |
8282 | ||
8283 | default: | |
8284 | return -EINVAL; | |
8285 | } | |
8286 | ||
8287 | if (!nmi_safe && !(event->pmu->capabilities & PERF_PMU_CAP_NO_NMI)) | |
8288 | return -EINVAL; | |
8289 | ||
8290 | return 0; | |
8291 | } | |
8292 | ||
0793a61d | 8293 | /** |
cdd6c482 | 8294 | * sys_perf_event_open - open a performance event, associate it to a task/cpu |
9f66a381 | 8295 | * |
cdd6c482 | 8296 | * @attr_uptr: event_id type attributes for monitoring/sampling |
0793a61d | 8297 | * @pid: target pid |
9f66a381 | 8298 | * @cpu: target cpu |
cdd6c482 | 8299 | * @group_fd: group leader event fd |
0793a61d | 8300 | */ |
cdd6c482 IM |
8301 | SYSCALL_DEFINE5(perf_event_open, |
8302 | struct perf_event_attr __user *, attr_uptr, | |
2743a5b0 | 8303 | pid_t, pid, int, cpu, int, group_fd, unsigned long, flags) |
0793a61d | 8304 | { |
b04243ef PZ |
8305 | struct perf_event *group_leader = NULL, *output_event = NULL; |
8306 | struct perf_event *event, *sibling; | |
cdd6c482 | 8307 | struct perf_event_attr attr; |
f63a8daa | 8308 | struct perf_event_context *ctx, *uninitialized_var(gctx); |
cdd6c482 | 8309 | struct file *event_file = NULL; |
2903ff01 | 8310 | struct fd group = {NULL, 0}; |
38a81da2 | 8311 | struct task_struct *task = NULL; |
89a1e187 | 8312 | struct pmu *pmu; |
ea635c64 | 8313 | int event_fd; |
b04243ef | 8314 | int move_group = 0; |
dc86cabe | 8315 | int err; |
a21b0b35 | 8316 | int f_flags = O_RDWR; |
79dff51e | 8317 | int cgroup_fd = -1; |
0793a61d | 8318 | |
2743a5b0 | 8319 | /* for future expandability... */ |
e5d1367f | 8320 | if (flags & ~PERF_FLAG_ALL) |
2743a5b0 PM |
8321 | return -EINVAL; |
8322 | ||
dc86cabe IM |
8323 | err = perf_copy_attr(attr_uptr, &attr); |
8324 | if (err) | |
8325 | return err; | |
eab656ae | 8326 | |
0764771d PZ |
8327 | if (!attr.exclude_kernel) { |
8328 | if (perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) | |
8329 | return -EACCES; | |
8330 | } | |
8331 | ||
df58ab24 | 8332 | if (attr.freq) { |
cdd6c482 | 8333 | if (attr.sample_freq > sysctl_perf_event_sample_rate) |
df58ab24 | 8334 | return -EINVAL; |
0819b2e3 PZ |
8335 | } else { |
8336 | if (attr.sample_period & (1ULL << 63)) | |
8337 | return -EINVAL; | |
df58ab24 PZ |
8338 | } |
8339 | ||
e5d1367f SE |
8340 | /* |
8341 | * In cgroup mode, the pid argument is used to pass the fd | |
8342 | * opened to the cgroup directory in cgroupfs. The cpu argument | |
8343 | * designates the cpu on which to monitor threads from that | |
8344 | * cgroup. | |
8345 | */ | |
8346 | if ((flags & PERF_FLAG_PID_CGROUP) && (pid == -1 || cpu == -1)) | |
8347 | return -EINVAL; | |
8348 | ||
a21b0b35 YD |
8349 | if (flags & PERF_FLAG_FD_CLOEXEC) |
8350 | f_flags |= O_CLOEXEC; | |
8351 | ||
8352 | event_fd = get_unused_fd_flags(f_flags); | |
ea635c64 AV |
8353 | if (event_fd < 0) |
8354 | return event_fd; | |
8355 | ||
ac9721f3 | 8356 | if (group_fd != -1) { |
2903ff01 AV |
8357 | err = perf_fget_light(group_fd, &group); |
8358 | if (err) | |
d14b12d7 | 8359 | goto err_fd; |
2903ff01 | 8360 | group_leader = group.file->private_data; |
ac9721f3 PZ |
8361 | if (flags & PERF_FLAG_FD_OUTPUT) |
8362 | output_event = group_leader; | |
8363 | if (flags & PERF_FLAG_FD_NO_GROUP) | |
8364 | group_leader = NULL; | |
8365 | } | |
8366 | ||
e5d1367f | 8367 | if (pid != -1 && !(flags & PERF_FLAG_PID_CGROUP)) { |
c6be5a5c PZ |
8368 | task = find_lively_task_by_vpid(pid); |
8369 | if (IS_ERR(task)) { | |
8370 | err = PTR_ERR(task); | |
8371 | goto err_group_fd; | |
8372 | } | |
8373 | } | |
8374 | ||
1f4ee503 PZ |
8375 | if (task && group_leader && |
8376 | group_leader->attr.inherit != attr.inherit) { | |
8377 | err = -EINVAL; | |
8378 | goto err_task; | |
8379 | } | |
8380 | ||
fbfc623f YZ |
8381 | get_online_cpus(); |
8382 | ||
79dff51e MF |
8383 | if (flags & PERF_FLAG_PID_CGROUP) |
8384 | cgroup_fd = pid; | |
8385 | ||
4dc0da86 | 8386 | event = perf_event_alloc(&attr, cpu, task, group_leader, NULL, |
79dff51e | 8387 | NULL, NULL, cgroup_fd); |
d14b12d7 SE |
8388 | if (IS_ERR(event)) { |
8389 | err = PTR_ERR(event); | |
1f4ee503 | 8390 | goto err_cpus; |
d14b12d7 SE |
8391 | } |
8392 | ||
53b25335 VW |
8393 | if (is_sampling_event(event)) { |
8394 | if (event->pmu->capabilities & PERF_PMU_CAP_NO_INTERRUPT) { | |
8395 | err = -ENOTSUPP; | |
8396 | goto err_alloc; | |
8397 | } | |
8398 | } | |
8399 | ||
89a1e187 PZ |
8400 | /* |
8401 | * Special case software events and allow them to be part of | |
8402 | * any hardware group. | |
8403 | */ | |
8404 | pmu = event->pmu; | |
b04243ef | 8405 | |
34f43927 PZ |
8406 | if (attr.use_clockid) { |
8407 | err = perf_event_set_clock(event, attr.clockid); | |
8408 | if (err) | |
8409 | goto err_alloc; | |
8410 | } | |
8411 | ||
b04243ef PZ |
8412 | if (group_leader && |
8413 | (is_software_event(event) != is_software_event(group_leader))) { | |
8414 | if (is_software_event(event)) { | |
8415 | /* | |
8416 | * If event and group_leader are not both a software | |
8417 | * event, and event is, then group leader is not. | |
8418 | * | |
8419 | * Allow the addition of software events to !software | |
8420 | * groups, this is safe because software events never | |
8421 | * fail to schedule. | |
8422 | */ | |
8423 | pmu = group_leader->pmu; | |
8424 | } else if (is_software_event(group_leader) && | |
8425 | (group_leader->group_flags & PERF_GROUP_SOFTWARE)) { | |
8426 | /* | |
8427 | * In case the group is a pure software group, and we | |
8428 | * try to add a hardware event, move the whole group to | |
8429 | * the hardware context. | |
8430 | */ | |
8431 | move_group = 1; | |
8432 | } | |
8433 | } | |
89a1e187 PZ |
8434 | |
8435 | /* | |
8436 | * Get the target context (task or percpu): | |
8437 | */ | |
4af57ef2 | 8438 | ctx = find_get_context(pmu, task, event); |
89a1e187 PZ |
8439 | if (IS_ERR(ctx)) { |
8440 | err = PTR_ERR(ctx); | |
c6be5a5c | 8441 | goto err_alloc; |
89a1e187 PZ |
8442 | } |
8443 | ||
bed5b25a AS |
8444 | if ((pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE) && group_leader) { |
8445 | err = -EBUSY; | |
8446 | goto err_context; | |
8447 | } | |
8448 | ||
fd1edb3a PZ |
8449 | if (task) { |
8450 | put_task_struct(task); | |
8451 | task = NULL; | |
8452 | } | |
8453 | ||
ccff286d | 8454 | /* |
cdd6c482 | 8455 | * Look up the group leader (we will attach this event to it): |
04289bb9 | 8456 | */ |
ac9721f3 | 8457 | if (group_leader) { |
dc86cabe | 8458 | err = -EINVAL; |
04289bb9 | 8459 | |
04289bb9 | 8460 | /* |
ccff286d IM |
8461 | * Do not allow a recursive hierarchy (this new sibling |
8462 | * becoming part of another group-sibling): | |
8463 | */ | |
8464 | if (group_leader->group_leader != group_leader) | |
c3f00c70 | 8465 | goto err_context; |
34f43927 PZ |
8466 | |
8467 | /* All events in a group should have the same clock */ | |
8468 | if (group_leader->clock != event->clock) | |
8469 | goto err_context; | |
8470 | ||
ccff286d IM |
8471 | /* |
8472 | * Do not allow to attach to a group in a different | |
8473 | * task or CPU context: | |
04289bb9 | 8474 | */ |
b04243ef | 8475 | if (move_group) { |
c3c87e77 PZ |
8476 | /* |
8477 | * Make sure we're both on the same task, or both | |
8478 | * per-cpu events. | |
8479 | */ | |
8480 | if (group_leader->ctx->task != ctx->task) | |
8481 | goto err_context; | |
8482 | ||
8483 | /* | |
8484 | * Make sure we're both events for the same CPU; | |
8485 | * grouping events for different CPUs is broken; since | |
8486 | * you can never concurrently schedule them anyhow. | |
8487 | */ | |
8488 | if (group_leader->cpu != event->cpu) | |
b04243ef PZ |
8489 | goto err_context; |
8490 | } else { | |
8491 | if (group_leader->ctx != ctx) | |
8492 | goto err_context; | |
8493 | } | |
8494 | ||
3b6f9e5c PM |
8495 | /* |
8496 | * Only a group leader can be exclusive or pinned | |
8497 | */ | |
0d48696f | 8498 | if (attr.exclusive || attr.pinned) |
c3f00c70 | 8499 | goto err_context; |
ac9721f3 PZ |
8500 | } |
8501 | ||
8502 | if (output_event) { | |
8503 | err = perf_event_set_output(event, output_event); | |
8504 | if (err) | |
c3f00c70 | 8505 | goto err_context; |
ac9721f3 | 8506 | } |
0793a61d | 8507 | |
a21b0b35 YD |
8508 | event_file = anon_inode_getfile("[perf_event]", &perf_fops, event, |
8509 | f_flags); | |
ea635c64 AV |
8510 | if (IS_ERR(event_file)) { |
8511 | err = PTR_ERR(event_file); | |
c3f00c70 | 8512 | goto err_context; |
ea635c64 | 8513 | } |
9b51f66d | 8514 | |
b04243ef | 8515 | if (move_group) { |
f63a8daa | 8516 | gctx = group_leader->ctx; |
f55fc2a5 | 8517 | mutex_lock_double(&gctx->mutex, &ctx->mutex); |
84c4e620 PZ |
8518 | if (gctx->task == TASK_TOMBSTONE) { |
8519 | err = -ESRCH; | |
8520 | goto err_locked; | |
8521 | } | |
f55fc2a5 PZ |
8522 | } else { |
8523 | mutex_lock(&ctx->mutex); | |
8524 | } | |
8525 | ||
84c4e620 PZ |
8526 | if (ctx->task == TASK_TOMBSTONE) { |
8527 | err = -ESRCH; | |
8528 | goto err_locked; | |
8529 | } | |
8530 | ||
a723968c PZ |
8531 | if (!perf_event_validate_size(event)) { |
8532 | err = -E2BIG; | |
8533 | goto err_locked; | |
8534 | } | |
8535 | ||
f55fc2a5 PZ |
8536 | /* |
8537 | * Must be under the same ctx::mutex as perf_install_in_context(), | |
8538 | * because we need to serialize with concurrent event creation. | |
8539 | */ | |
8540 | if (!exclusive_event_installable(event, ctx)) { | |
8541 | /* exclusive and group stuff are assumed mutually exclusive */ | |
8542 | WARN_ON_ONCE(move_group); | |
f63a8daa | 8543 | |
f55fc2a5 PZ |
8544 | err = -EBUSY; |
8545 | goto err_locked; | |
8546 | } | |
f63a8daa | 8547 | |
f55fc2a5 PZ |
8548 | WARN_ON_ONCE(ctx->parent_ctx); |
8549 | ||
8550 | if (move_group) { | |
f63a8daa PZ |
8551 | /* |
8552 | * See perf_event_ctx_lock() for comments on the details | |
8553 | * of swizzling perf_event::ctx. | |
8554 | */ | |
45a0e07a | 8555 | perf_remove_from_context(group_leader, 0); |
0231bb53 | 8556 | |
b04243ef PZ |
8557 | list_for_each_entry(sibling, &group_leader->sibling_list, |
8558 | group_entry) { | |
45a0e07a | 8559 | perf_remove_from_context(sibling, 0); |
b04243ef PZ |
8560 | put_ctx(gctx); |
8561 | } | |
b04243ef | 8562 | |
f63a8daa PZ |
8563 | /* |
8564 | * Wait for everybody to stop referencing the events through | |
8565 | * the old lists, before installing it on new lists. | |
8566 | */ | |
0cda4c02 | 8567 | synchronize_rcu(); |
f63a8daa | 8568 | |
8f95b435 PZI |
8569 | /* |
8570 | * Install the group siblings before the group leader. | |
8571 | * | |
8572 | * Because a group leader will try and install the entire group | |
8573 | * (through the sibling list, which is still in-tact), we can | |
8574 | * end up with siblings installed in the wrong context. | |
8575 | * | |
8576 | * By installing siblings first we NO-OP because they're not | |
8577 | * reachable through the group lists. | |
8578 | */ | |
b04243ef PZ |
8579 | list_for_each_entry(sibling, &group_leader->sibling_list, |
8580 | group_entry) { | |
8f95b435 | 8581 | perf_event__state_init(sibling); |
9fc81d87 | 8582 | perf_install_in_context(ctx, sibling, sibling->cpu); |
b04243ef PZ |
8583 | get_ctx(ctx); |
8584 | } | |
8f95b435 PZI |
8585 | |
8586 | /* | |
8587 | * Removing from the context ends up with disabled | |
8588 | * event. What we want here is event in the initial | |
8589 | * startup state, ready to be add into new context. | |
8590 | */ | |
8591 | perf_event__state_init(group_leader); | |
8592 | perf_install_in_context(ctx, group_leader, group_leader->cpu); | |
8593 | get_ctx(ctx); | |
b04243ef | 8594 | |
f55fc2a5 PZ |
8595 | /* |
8596 | * Now that all events are installed in @ctx, nothing | |
8597 | * references @gctx anymore, so drop the last reference we have | |
8598 | * on it. | |
8599 | */ | |
8600 | put_ctx(gctx); | |
bed5b25a AS |
8601 | } |
8602 | ||
f73e22ab PZ |
8603 | /* |
8604 | * Precalculate sample_data sizes; do while holding ctx::mutex such | |
8605 | * that we're serialized against further additions and before | |
8606 | * perf_install_in_context() which is the point the event is active and | |
8607 | * can use these values. | |
8608 | */ | |
8609 | perf_event__header_size(event); | |
8610 | perf_event__id_header_size(event); | |
8611 | ||
78cd2c74 PZ |
8612 | event->owner = current; |
8613 | ||
e2d37cd2 | 8614 | perf_install_in_context(ctx, event, event->cpu); |
fe4b04fa | 8615 | perf_unpin_context(ctx); |
f63a8daa | 8616 | |
f55fc2a5 | 8617 | if (move_group) |
f63a8daa | 8618 | mutex_unlock(&gctx->mutex); |
d859e29f | 8619 | mutex_unlock(&ctx->mutex); |
9b51f66d | 8620 | |
fbfc623f YZ |
8621 | put_online_cpus(); |
8622 | ||
cdd6c482 IM |
8623 | mutex_lock(¤t->perf_event_mutex); |
8624 | list_add_tail(&event->owner_entry, ¤t->perf_event_list); | |
8625 | mutex_unlock(¤t->perf_event_mutex); | |
082ff5a2 | 8626 | |
8a49542c PZ |
8627 | /* |
8628 | * Drop the reference on the group_event after placing the | |
8629 | * new event on the sibling_list. This ensures destruction | |
8630 | * of the group leader will find the pointer to itself in | |
8631 | * perf_group_detach(). | |
8632 | */ | |
2903ff01 | 8633 | fdput(group); |
ea635c64 AV |
8634 | fd_install(event_fd, event_file); |
8635 | return event_fd; | |
0793a61d | 8636 | |
f55fc2a5 PZ |
8637 | err_locked: |
8638 | if (move_group) | |
8639 | mutex_unlock(&gctx->mutex); | |
8640 | mutex_unlock(&ctx->mutex); | |
8641 | /* err_file: */ | |
8642 | fput(event_file); | |
c3f00c70 | 8643 | err_context: |
fe4b04fa | 8644 | perf_unpin_context(ctx); |
ea635c64 | 8645 | put_ctx(ctx); |
c6be5a5c | 8646 | err_alloc: |
13005627 PZ |
8647 | /* |
8648 | * If event_file is set, the fput() above will have called ->release() | |
8649 | * and that will take care of freeing the event. | |
8650 | */ | |
8651 | if (!event_file) | |
8652 | free_event(event); | |
1f4ee503 | 8653 | err_cpus: |
fbfc623f | 8654 | put_online_cpus(); |
1f4ee503 | 8655 | err_task: |
e7d0bc04 PZ |
8656 | if (task) |
8657 | put_task_struct(task); | |
89a1e187 | 8658 | err_group_fd: |
2903ff01 | 8659 | fdput(group); |
ea635c64 AV |
8660 | err_fd: |
8661 | put_unused_fd(event_fd); | |
dc86cabe | 8662 | return err; |
0793a61d TG |
8663 | } |
8664 | ||
fb0459d7 AV |
8665 | /** |
8666 | * perf_event_create_kernel_counter | |
8667 | * | |
8668 | * @attr: attributes of the counter to create | |
8669 | * @cpu: cpu in which the counter is bound | |
38a81da2 | 8670 | * @task: task to profile (NULL for percpu) |
fb0459d7 AV |
8671 | */ |
8672 | struct perf_event * | |
8673 | perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, | |
38a81da2 | 8674 | struct task_struct *task, |
4dc0da86 AK |
8675 | perf_overflow_handler_t overflow_handler, |
8676 | void *context) | |
fb0459d7 | 8677 | { |
fb0459d7 | 8678 | struct perf_event_context *ctx; |
c3f00c70 | 8679 | struct perf_event *event; |
fb0459d7 | 8680 | int err; |
d859e29f | 8681 | |
fb0459d7 AV |
8682 | /* |
8683 | * Get the target context (task or percpu): | |
8684 | */ | |
d859e29f | 8685 | |
4dc0da86 | 8686 | event = perf_event_alloc(attr, cpu, task, NULL, NULL, |
79dff51e | 8687 | overflow_handler, context, -1); |
c3f00c70 PZ |
8688 | if (IS_ERR(event)) { |
8689 | err = PTR_ERR(event); | |
8690 | goto err; | |
8691 | } | |
d859e29f | 8692 | |
f8697762 | 8693 | /* Mark owner so we could distinguish it from user events. */ |
63b6da39 | 8694 | event->owner = TASK_TOMBSTONE; |
f8697762 | 8695 | |
4af57ef2 | 8696 | ctx = find_get_context(event->pmu, task, event); |
c6567f64 FW |
8697 | if (IS_ERR(ctx)) { |
8698 | err = PTR_ERR(ctx); | |
c3f00c70 | 8699 | goto err_free; |
d859e29f | 8700 | } |
fb0459d7 | 8701 | |
fb0459d7 AV |
8702 | WARN_ON_ONCE(ctx->parent_ctx); |
8703 | mutex_lock(&ctx->mutex); | |
84c4e620 PZ |
8704 | if (ctx->task == TASK_TOMBSTONE) { |
8705 | err = -ESRCH; | |
8706 | goto err_unlock; | |
8707 | } | |
8708 | ||
bed5b25a | 8709 | if (!exclusive_event_installable(event, ctx)) { |
bed5b25a | 8710 | err = -EBUSY; |
84c4e620 | 8711 | goto err_unlock; |
bed5b25a AS |
8712 | } |
8713 | ||
fb0459d7 | 8714 | perf_install_in_context(ctx, event, cpu); |
fe4b04fa | 8715 | perf_unpin_context(ctx); |
fb0459d7 AV |
8716 | mutex_unlock(&ctx->mutex); |
8717 | ||
fb0459d7 AV |
8718 | return event; |
8719 | ||
84c4e620 PZ |
8720 | err_unlock: |
8721 | mutex_unlock(&ctx->mutex); | |
8722 | perf_unpin_context(ctx); | |
8723 | put_ctx(ctx); | |
c3f00c70 PZ |
8724 | err_free: |
8725 | free_event(event); | |
8726 | err: | |
c6567f64 | 8727 | return ERR_PTR(err); |
9b51f66d | 8728 | } |
fb0459d7 | 8729 | EXPORT_SYMBOL_GPL(perf_event_create_kernel_counter); |
9b51f66d | 8730 | |
0cda4c02 YZ |
8731 | void perf_pmu_migrate_context(struct pmu *pmu, int src_cpu, int dst_cpu) |
8732 | { | |
8733 | struct perf_event_context *src_ctx; | |
8734 | struct perf_event_context *dst_ctx; | |
8735 | struct perf_event *event, *tmp; | |
8736 | LIST_HEAD(events); | |
8737 | ||
8738 | src_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, src_cpu)->ctx; | |
8739 | dst_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, dst_cpu)->ctx; | |
8740 | ||
f63a8daa PZ |
8741 | /* |
8742 | * See perf_event_ctx_lock() for comments on the details | |
8743 | * of swizzling perf_event::ctx. | |
8744 | */ | |
8745 | mutex_lock_double(&src_ctx->mutex, &dst_ctx->mutex); | |
0cda4c02 YZ |
8746 | list_for_each_entry_safe(event, tmp, &src_ctx->event_list, |
8747 | event_entry) { | |
45a0e07a | 8748 | perf_remove_from_context(event, 0); |
9a545de0 | 8749 | unaccount_event_cpu(event, src_cpu); |
0cda4c02 | 8750 | put_ctx(src_ctx); |
9886167d | 8751 | list_add(&event->migrate_entry, &events); |
0cda4c02 | 8752 | } |
0cda4c02 | 8753 | |
8f95b435 PZI |
8754 | /* |
8755 | * Wait for the events to quiesce before re-instating them. | |
8756 | */ | |
0cda4c02 YZ |
8757 | synchronize_rcu(); |
8758 | ||
8f95b435 PZI |
8759 | /* |
8760 | * Re-instate events in 2 passes. | |
8761 | * | |
8762 | * Skip over group leaders and only install siblings on this first | |
8763 | * pass, siblings will not get enabled without a leader, however a | |
8764 | * leader will enable its siblings, even if those are still on the old | |
8765 | * context. | |
8766 | */ | |
8767 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { | |
8768 | if (event->group_leader == event) | |
8769 | continue; | |
8770 | ||
8771 | list_del(&event->migrate_entry); | |
8772 | if (event->state >= PERF_EVENT_STATE_OFF) | |
8773 | event->state = PERF_EVENT_STATE_INACTIVE; | |
8774 | account_event_cpu(event, dst_cpu); | |
8775 | perf_install_in_context(dst_ctx, event, dst_cpu); | |
8776 | get_ctx(dst_ctx); | |
8777 | } | |
8778 | ||
8779 | /* | |
8780 | * Once all the siblings are setup properly, install the group leaders | |
8781 | * to make it go. | |
8782 | */ | |
9886167d PZ |
8783 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { |
8784 | list_del(&event->migrate_entry); | |
0cda4c02 YZ |
8785 | if (event->state >= PERF_EVENT_STATE_OFF) |
8786 | event->state = PERF_EVENT_STATE_INACTIVE; | |
9a545de0 | 8787 | account_event_cpu(event, dst_cpu); |
0cda4c02 YZ |
8788 | perf_install_in_context(dst_ctx, event, dst_cpu); |
8789 | get_ctx(dst_ctx); | |
8790 | } | |
8791 | mutex_unlock(&dst_ctx->mutex); | |
f63a8daa | 8792 | mutex_unlock(&src_ctx->mutex); |
0cda4c02 YZ |
8793 | } |
8794 | EXPORT_SYMBOL_GPL(perf_pmu_migrate_context); | |
8795 | ||
cdd6c482 | 8796 | static void sync_child_event(struct perf_event *child_event, |
38b200d6 | 8797 | struct task_struct *child) |
d859e29f | 8798 | { |
cdd6c482 | 8799 | struct perf_event *parent_event = child_event->parent; |
8bc20959 | 8800 | u64 child_val; |
d859e29f | 8801 | |
cdd6c482 IM |
8802 | if (child_event->attr.inherit_stat) |
8803 | perf_event_read_event(child_event, child); | |
38b200d6 | 8804 | |
b5e58793 | 8805 | child_val = perf_event_count(child_event); |
d859e29f PM |
8806 | |
8807 | /* | |
8808 | * Add back the child's count to the parent's count: | |
8809 | */ | |
a6e6dea6 | 8810 | atomic64_add(child_val, &parent_event->child_count); |
cdd6c482 IM |
8811 | atomic64_add(child_event->total_time_enabled, |
8812 | &parent_event->child_total_time_enabled); | |
8813 | atomic64_add(child_event->total_time_running, | |
8814 | &parent_event->child_total_time_running); | |
d859e29f PM |
8815 | } |
8816 | ||
9b51f66d | 8817 | static void |
8ba289b8 PZ |
8818 | perf_event_exit_event(struct perf_event *child_event, |
8819 | struct perf_event_context *child_ctx, | |
8820 | struct task_struct *child) | |
9b51f66d | 8821 | { |
8ba289b8 PZ |
8822 | struct perf_event *parent_event = child_event->parent; |
8823 | ||
1903d50c PZ |
8824 | /* |
8825 | * Do not destroy the 'original' grouping; because of the context | |
8826 | * switch optimization the original events could've ended up in a | |
8827 | * random child task. | |
8828 | * | |
8829 | * If we were to destroy the original group, all group related | |
8830 | * operations would cease to function properly after this random | |
8831 | * child dies. | |
8832 | * | |
8833 | * Do destroy all inherited groups, we don't care about those | |
8834 | * and being thorough is better. | |
8835 | */ | |
32132a3d PZ |
8836 | raw_spin_lock_irq(&child_ctx->lock); |
8837 | WARN_ON_ONCE(child_ctx->is_active); | |
8838 | ||
8ba289b8 | 8839 | if (parent_event) |
32132a3d PZ |
8840 | perf_group_detach(child_event); |
8841 | list_del_event(child_event, child_ctx); | |
a69b0ca4 | 8842 | child_event->state = PERF_EVENT_STATE_EXIT; /* is_event_hup() */ |
32132a3d | 8843 | raw_spin_unlock_irq(&child_ctx->lock); |
0cc0c027 | 8844 | |
9b51f66d | 8845 | /* |
8ba289b8 | 8846 | * Parent events are governed by their filedesc, retain them. |
9b51f66d | 8847 | */ |
8ba289b8 | 8848 | if (!parent_event) { |
179033b3 | 8849 | perf_event_wakeup(child_event); |
8ba289b8 | 8850 | return; |
4bcf349a | 8851 | } |
8ba289b8 PZ |
8852 | /* |
8853 | * Child events can be cleaned up. | |
8854 | */ | |
8855 | ||
8856 | sync_child_event(child_event, child); | |
8857 | ||
8858 | /* | |
8859 | * Remove this event from the parent's list | |
8860 | */ | |
8861 | WARN_ON_ONCE(parent_event->ctx->parent_ctx); | |
8862 | mutex_lock(&parent_event->child_mutex); | |
8863 | list_del_init(&child_event->child_list); | |
8864 | mutex_unlock(&parent_event->child_mutex); | |
8865 | ||
8866 | /* | |
8867 | * Kick perf_poll() for is_event_hup(). | |
8868 | */ | |
8869 | perf_event_wakeup(parent_event); | |
8870 | free_event(child_event); | |
8871 | put_event(parent_event); | |
9b51f66d IM |
8872 | } |
8873 | ||
8dc85d54 | 8874 | static void perf_event_exit_task_context(struct task_struct *child, int ctxn) |
9b51f66d | 8875 | { |
211de6eb | 8876 | struct perf_event_context *child_ctx, *clone_ctx = NULL; |
63b6da39 | 8877 | struct perf_event *child_event, *next; |
63b6da39 PZ |
8878 | |
8879 | WARN_ON_ONCE(child != current); | |
9b51f66d | 8880 | |
6a3351b6 | 8881 | child_ctx = perf_pin_task_context(child, ctxn); |
63b6da39 | 8882 | if (!child_ctx) |
9b51f66d IM |
8883 | return; |
8884 | ||
ad3a37de | 8885 | /* |
6a3351b6 PZ |
8886 | * In order to reduce the amount of tricky in ctx tear-down, we hold |
8887 | * ctx::mutex over the entire thing. This serializes against almost | |
8888 | * everything that wants to access the ctx. | |
8889 | * | |
8890 | * The exception is sys_perf_event_open() / | |
8891 | * perf_event_create_kernel_count() which does find_get_context() | |
8892 | * without ctx::mutex (it cannot because of the move_group double mutex | |
8893 | * lock thing). See the comments in perf_install_in_context(). | |
ad3a37de | 8894 | */ |
6a3351b6 | 8895 | mutex_lock(&child_ctx->mutex); |
c93f7669 PM |
8896 | |
8897 | /* | |
6a3351b6 PZ |
8898 | * In a single ctx::lock section, de-schedule the events and detach the |
8899 | * context from the task such that we cannot ever get it scheduled back | |
8900 | * in. | |
c93f7669 | 8901 | */ |
6a3351b6 | 8902 | raw_spin_lock_irq(&child_ctx->lock); |
63b6da39 | 8903 | task_ctx_sched_out(__get_cpu_context(child_ctx), child_ctx); |
4a1c0f26 | 8904 | |
71a851b4 | 8905 | /* |
63b6da39 PZ |
8906 | * Now that the context is inactive, destroy the task <-> ctx relation |
8907 | * and mark the context dead. | |
71a851b4 | 8908 | */ |
63b6da39 PZ |
8909 | RCU_INIT_POINTER(child->perf_event_ctxp[ctxn], NULL); |
8910 | put_ctx(child_ctx); /* cannot be last */ | |
8911 | WRITE_ONCE(child_ctx->task, TASK_TOMBSTONE); | |
8912 | put_task_struct(current); /* cannot be last */ | |
4a1c0f26 | 8913 | |
211de6eb | 8914 | clone_ctx = unclone_ctx(child_ctx); |
6a3351b6 | 8915 | raw_spin_unlock_irq(&child_ctx->lock); |
9f498cc5 | 8916 | |
211de6eb PZ |
8917 | if (clone_ctx) |
8918 | put_ctx(clone_ctx); | |
4a1c0f26 | 8919 | |
9f498cc5 | 8920 | /* |
cdd6c482 IM |
8921 | * Report the task dead after unscheduling the events so that we |
8922 | * won't get any samples after PERF_RECORD_EXIT. We can however still | |
8923 | * get a few PERF_RECORD_READ events. | |
9f498cc5 | 8924 | */ |
cdd6c482 | 8925 | perf_event_task(child, child_ctx, 0); |
a63eaf34 | 8926 | |
ebf905fc | 8927 | list_for_each_entry_safe(child_event, next, &child_ctx->event_list, event_entry) |
8ba289b8 | 8928 | perf_event_exit_event(child_event, child_ctx, child); |
8bc20959 | 8929 | |
a63eaf34 PM |
8930 | mutex_unlock(&child_ctx->mutex); |
8931 | ||
8932 | put_ctx(child_ctx); | |
9b51f66d IM |
8933 | } |
8934 | ||
8dc85d54 PZ |
8935 | /* |
8936 | * When a child task exits, feed back event values to parent events. | |
8937 | */ | |
8938 | void perf_event_exit_task(struct task_struct *child) | |
8939 | { | |
8882135b | 8940 | struct perf_event *event, *tmp; |
8dc85d54 PZ |
8941 | int ctxn; |
8942 | ||
8882135b PZ |
8943 | mutex_lock(&child->perf_event_mutex); |
8944 | list_for_each_entry_safe(event, tmp, &child->perf_event_list, | |
8945 | owner_entry) { | |
8946 | list_del_init(&event->owner_entry); | |
8947 | ||
8948 | /* | |
8949 | * Ensure the list deletion is visible before we clear | |
8950 | * the owner, closes a race against perf_release() where | |
8951 | * we need to serialize on the owner->perf_event_mutex. | |
8952 | */ | |
f47c02c0 | 8953 | smp_store_release(&event->owner, NULL); |
8882135b PZ |
8954 | } |
8955 | mutex_unlock(&child->perf_event_mutex); | |
8956 | ||
8dc85d54 PZ |
8957 | for_each_task_context_nr(ctxn) |
8958 | perf_event_exit_task_context(child, ctxn); | |
4e93ad60 JO |
8959 | |
8960 | /* | |
8961 | * The perf_event_exit_task_context calls perf_event_task | |
8962 | * with child's task_ctx, which generates EXIT events for | |
8963 | * child contexts and sets child->perf_event_ctxp[] to NULL. | |
8964 | * At this point we need to send EXIT events to cpu contexts. | |
8965 | */ | |
8966 | perf_event_task(child, NULL, 0); | |
8dc85d54 PZ |
8967 | } |
8968 | ||
889ff015 FW |
8969 | static void perf_free_event(struct perf_event *event, |
8970 | struct perf_event_context *ctx) | |
8971 | { | |
8972 | struct perf_event *parent = event->parent; | |
8973 | ||
8974 | if (WARN_ON_ONCE(!parent)) | |
8975 | return; | |
8976 | ||
8977 | mutex_lock(&parent->child_mutex); | |
8978 | list_del_init(&event->child_list); | |
8979 | mutex_unlock(&parent->child_mutex); | |
8980 | ||
a6fa941d | 8981 | put_event(parent); |
889ff015 | 8982 | |
652884fe | 8983 | raw_spin_lock_irq(&ctx->lock); |
8a49542c | 8984 | perf_group_detach(event); |
889ff015 | 8985 | list_del_event(event, ctx); |
652884fe | 8986 | raw_spin_unlock_irq(&ctx->lock); |
889ff015 FW |
8987 | free_event(event); |
8988 | } | |
8989 | ||
bbbee908 | 8990 | /* |
652884fe | 8991 | * Free an unexposed, unused context as created by inheritance by |
8dc85d54 | 8992 | * perf_event_init_task below, used by fork() in case of fail. |
652884fe PZ |
8993 | * |
8994 | * Not all locks are strictly required, but take them anyway to be nice and | |
8995 | * help out with the lockdep assertions. | |
bbbee908 | 8996 | */ |
cdd6c482 | 8997 | void perf_event_free_task(struct task_struct *task) |
bbbee908 | 8998 | { |
8dc85d54 | 8999 | struct perf_event_context *ctx; |
cdd6c482 | 9000 | struct perf_event *event, *tmp; |
8dc85d54 | 9001 | int ctxn; |
bbbee908 | 9002 | |
8dc85d54 PZ |
9003 | for_each_task_context_nr(ctxn) { |
9004 | ctx = task->perf_event_ctxp[ctxn]; | |
9005 | if (!ctx) | |
9006 | continue; | |
bbbee908 | 9007 | |
8dc85d54 | 9008 | mutex_lock(&ctx->mutex); |
bbbee908 | 9009 | again: |
8dc85d54 PZ |
9010 | list_for_each_entry_safe(event, tmp, &ctx->pinned_groups, |
9011 | group_entry) | |
9012 | perf_free_event(event, ctx); | |
bbbee908 | 9013 | |
8dc85d54 PZ |
9014 | list_for_each_entry_safe(event, tmp, &ctx->flexible_groups, |
9015 | group_entry) | |
9016 | perf_free_event(event, ctx); | |
bbbee908 | 9017 | |
8dc85d54 PZ |
9018 | if (!list_empty(&ctx->pinned_groups) || |
9019 | !list_empty(&ctx->flexible_groups)) | |
9020 | goto again; | |
bbbee908 | 9021 | |
8dc85d54 | 9022 | mutex_unlock(&ctx->mutex); |
bbbee908 | 9023 | |
8dc85d54 PZ |
9024 | put_ctx(ctx); |
9025 | } | |
889ff015 FW |
9026 | } |
9027 | ||
4e231c79 PZ |
9028 | void perf_event_delayed_put(struct task_struct *task) |
9029 | { | |
9030 | int ctxn; | |
9031 | ||
9032 | for_each_task_context_nr(ctxn) | |
9033 | WARN_ON_ONCE(task->perf_event_ctxp[ctxn]); | |
9034 | } | |
9035 | ||
e03e7ee3 | 9036 | struct file *perf_event_get(unsigned int fd) |
ffe8690c | 9037 | { |
e03e7ee3 | 9038 | struct file *file; |
ffe8690c | 9039 | |
e03e7ee3 AS |
9040 | file = fget_raw(fd); |
9041 | if (!file) | |
9042 | return ERR_PTR(-EBADF); | |
ffe8690c | 9043 | |
e03e7ee3 AS |
9044 | if (file->f_op != &perf_fops) { |
9045 | fput(file); | |
9046 | return ERR_PTR(-EBADF); | |
9047 | } | |
ffe8690c | 9048 | |
e03e7ee3 | 9049 | return file; |
ffe8690c KX |
9050 | } |
9051 | ||
9052 | const struct perf_event_attr *perf_event_attrs(struct perf_event *event) | |
9053 | { | |
9054 | if (!event) | |
9055 | return ERR_PTR(-EINVAL); | |
9056 | ||
9057 | return &event->attr; | |
9058 | } | |
9059 | ||
97dee4f3 PZ |
9060 | /* |
9061 | * inherit a event from parent task to child task: | |
9062 | */ | |
9063 | static struct perf_event * | |
9064 | inherit_event(struct perf_event *parent_event, | |
9065 | struct task_struct *parent, | |
9066 | struct perf_event_context *parent_ctx, | |
9067 | struct task_struct *child, | |
9068 | struct perf_event *group_leader, | |
9069 | struct perf_event_context *child_ctx) | |
9070 | { | |
1929def9 | 9071 | enum perf_event_active_state parent_state = parent_event->state; |
97dee4f3 | 9072 | struct perf_event *child_event; |
cee010ec | 9073 | unsigned long flags; |
97dee4f3 PZ |
9074 | |
9075 | /* | |
9076 | * Instead of creating recursive hierarchies of events, | |
9077 | * we link inherited events back to the original parent, | |
9078 | * which has a filp for sure, which we use as the reference | |
9079 | * count: | |
9080 | */ | |
9081 | if (parent_event->parent) | |
9082 | parent_event = parent_event->parent; | |
9083 | ||
9084 | child_event = perf_event_alloc(&parent_event->attr, | |
9085 | parent_event->cpu, | |
d580ff86 | 9086 | child, |
97dee4f3 | 9087 | group_leader, parent_event, |
79dff51e | 9088 | NULL, NULL, -1); |
97dee4f3 PZ |
9089 | if (IS_ERR(child_event)) |
9090 | return child_event; | |
a6fa941d | 9091 | |
c6e5b732 PZ |
9092 | /* |
9093 | * is_orphaned_event() and list_add_tail(&parent_event->child_list) | |
9094 | * must be under the same lock in order to serialize against | |
9095 | * perf_event_release_kernel(), such that either we must observe | |
9096 | * is_orphaned_event() or they will observe us on the child_list. | |
9097 | */ | |
9098 | mutex_lock(&parent_event->child_mutex); | |
fadfe7be JO |
9099 | if (is_orphaned_event(parent_event) || |
9100 | !atomic_long_inc_not_zero(&parent_event->refcount)) { | |
c6e5b732 | 9101 | mutex_unlock(&parent_event->child_mutex); |
a6fa941d AV |
9102 | free_event(child_event); |
9103 | return NULL; | |
9104 | } | |
9105 | ||
97dee4f3 PZ |
9106 | get_ctx(child_ctx); |
9107 | ||
9108 | /* | |
9109 | * Make the child state follow the state of the parent event, | |
9110 | * not its attr.disabled bit. We hold the parent's mutex, | |
9111 | * so we won't race with perf_event_{en, dis}able_family. | |
9112 | */ | |
1929def9 | 9113 | if (parent_state >= PERF_EVENT_STATE_INACTIVE) |
97dee4f3 PZ |
9114 | child_event->state = PERF_EVENT_STATE_INACTIVE; |
9115 | else | |
9116 | child_event->state = PERF_EVENT_STATE_OFF; | |
9117 | ||
9118 | if (parent_event->attr.freq) { | |
9119 | u64 sample_period = parent_event->hw.sample_period; | |
9120 | struct hw_perf_event *hwc = &child_event->hw; | |
9121 | ||
9122 | hwc->sample_period = sample_period; | |
9123 | hwc->last_period = sample_period; | |
9124 | ||
9125 | local64_set(&hwc->period_left, sample_period); | |
9126 | } | |
9127 | ||
9128 | child_event->ctx = child_ctx; | |
9129 | child_event->overflow_handler = parent_event->overflow_handler; | |
4dc0da86 AK |
9130 | child_event->overflow_handler_context |
9131 | = parent_event->overflow_handler_context; | |
97dee4f3 | 9132 | |
614b6780 TG |
9133 | /* |
9134 | * Precalculate sample_data sizes | |
9135 | */ | |
9136 | perf_event__header_size(child_event); | |
6844c09d | 9137 | perf_event__id_header_size(child_event); |
614b6780 | 9138 | |
97dee4f3 PZ |
9139 | /* |
9140 | * Link it up in the child's context: | |
9141 | */ | |
cee010ec | 9142 | raw_spin_lock_irqsave(&child_ctx->lock, flags); |
97dee4f3 | 9143 | add_event_to_ctx(child_event, child_ctx); |
cee010ec | 9144 | raw_spin_unlock_irqrestore(&child_ctx->lock, flags); |
97dee4f3 | 9145 | |
97dee4f3 PZ |
9146 | /* |
9147 | * Link this into the parent event's child list | |
9148 | */ | |
97dee4f3 PZ |
9149 | list_add_tail(&child_event->child_list, &parent_event->child_list); |
9150 | mutex_unlock(&parent_event->child_mutex); | |
9151 | ||
9152 | return child_event; | |
9153 | } | |
9154 | ||
9155 | static int inherit_group(struct perf_event *parent_event, | |
9156 | struct task_struct *parent, | |
9157 | struct perf_event_context *parent_ctx, | |
9158 | struct task_struct *child, | |
9159 | struct perf_event_context *child_ctx) | |
9160 | { | |
9161 | struct perf_event *leader; | |
9162 | struct perf_event *sub; | |
9163 | struct perf_event *child_ctr; | |
9164 | ||
9165 | leader = inherit_event(parent_event, parent, parent_ctx, | |
9166 | child, NULL, child_ctx); | |
9167 | if (IS_ERR(leader)) | |
9168 | return PTR_ERR(leader); | |
9169 | list_for_each_entry(sub, &parent_event->sibling_list, group_entry) { | |
9170 | child_ctr = inherit_event(sub, parent, parent_ctx, | |
9171 | child, leader, child_ctx); | |
9172 | if (IS_ERR(child_ctr)) | |
9173 | return PTR_ERR(child_ctr); | |
9174 | } | |
9175 | return 0; | |
889ff015 FW |
9176 | } |
9177 | ||
9178 | static int | |
9179 | inherit_task_group(struct perf_event *event, struct task_struct *parent, | |
9180 | struct perf_event_context *parent_ctx, | |
8dc85d54 | 9181 | struct task_struct *child, int ctxn, |
889ff015 FW |
9182 | int *inherited_all) |
9183 | { | |
9184 | int ret; | |
8dc85d54 | 9185 | struct perf_event_context *child_ctx; |
889ff015 FW |
9186 | |
9187 | if (!event->attr.inherit) { | |
9188 | *inherited_all = 0; | |
9189 | return 0; | |
bbbee908 PZ |
9190 | } |
9191 | ||
fe4b04fa | 9192 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 FW |
9193 | if (!child_ctx) { |
9194 | /* | |
9195 | * This is executed from the parent task context, so | |
9196 | * inherit events that have been marked for cloning. | |
9197 | * First allocate and initialize a context for the | |
9198 | * child. | |
9199 | */ | |
bbbee908 | 9200 | |
734df5ab | 9201 | child_ctx = alloc_perf_context(parent_ctx->pmu, child); |
889ff015 FW |
9202 | if (!child_ctx) |
9203 | return -ENOMEM; | |
bbbee908 | 9204 | |
8dc85d54 | 9205 | child->perf_event_ctxp[ctxn] = child_ctx; |
889ff015 FW |
9206 | } |
9207 | ||
9208 | ret = inherit_group(event, parent, parent_ctx, | |
9209 | child, child_ctx); | |
9210 | ||
9211 | if (ret) | |
9212 | *inherited_all = 0; | |
9213 | ||
9214 | return ret; | |
bbbee908 PZ |
9215 | } |
9216 | ||
9b51f66d | 9217 | /* |
cdd6c482 | 9218 | * Initialize the perf_event context in task_struct |
9b51f66d | 9219 | */ |
985c8dcb | 9220 | static int perf_event_init_context(struct task_struct *child, int ctxn) |
9b51f66d | 9221 | { |
889ff015 | 9222 | struct perf_event_context *child_ctx, *parent_ctx; |
cdd6c482 IM |
9223 | struct perf_event_context *cloned_ctx; |
9224 | struct perf_event *event; | |
9b51f66d | 9225 | struct task_struct *parent = current; |
564c2b21 | 9226 | int inherited_all = 1; |
dddd3379 | 9227 | unsigned long flags; |
6ab423e0 | 9228 | int ret = 0; |
9b51f66d | 9229 | |
8dc85d54 | 9230 | if (likely(!parent->perf_event_ctxp[ctxn])) |
6ab423e0 PZ |
9231 | return 0; |
9232 | ||
ad3a37de | 9233 | /* |
25346b93 PM |
9234 | * If the parent's context is a clone, pin it so it won't get |
9235 | * swapped under us. | |
ad3a37de | 9236 | */ |
8dc85d54 | 9237 | parent_ctx = perf_pin_task_context(parent, ctxn); |
ffb4ef21 PZ |
9238 | if (!parent_ctx) |
9239 | return 0; | |
25346b93 | 9240 | |
ad3a37de PM |
9241 | /* |
9242 | * No need to check if parent_ctx != NULL here; since we saw | |
9243 | * it non-NULL earlier, the only reason for it to become NULL | |
9244 | * is if we exit, and since we're currently in the middle of | |
9245 | * a fork we can't be exiting at the same time. | |
9246 | */ | |
ad3a37de | 9247 | |
9b51f66d IM |
9248 | /* |
9249 | * Lock the parent list. No need to lock the child - not PID | |
9250 | * hashed yet and not running, so nobody can access it. | |
9251 | */ | |
d859e29f | 9252 | mutex_lock(&parent_ctx->mutex); |
9b51f66d IM |
9253 | |
9254 | /* | |
9255 | * We dont have to disable NMIs - we are only looking at | |
9256 | * the list, not manipulating it: | |
9257 | */ | |
889ff015 | 9258 | list_for_each_entry(event, &parent_ctx->pinned_groups, group_entry) { |
8dc85d54 PZ |
9259 | ret = inherit_task_group(event, parent, parent_ctx, |
9260 | child, ctxn, &inherited_all); | |
889ff015 FW |
9261 | if (ret) |
9262 | break; | |
9263 | } | |
b93f7978 | 9264 | |
dddd3379 TG |
9265 | /* |
9266 | * We can't hold ctx->lock when iterating the ->flexible_group list due | |
9267 | * to allocations, but we need to prevent rotation because | |
9268 | * rotate_ctx() will change the list from interrupt context. | |
9269 | */ | |
9270 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); | |
9271 | parent_ctx->rotate_disable = 1; | |
9272 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); | |
9273 | ||
889ff015 | 9274 | list_for_each_entry(event, &parent_ctx->flexible_groups, group_entry) { |
8dc85d54 PZ |
9275 | ret = inherit_task_group(event, parent, parent_ctx, |
9276 | child, ctxn, &inherited_all); | |
889ff015 | 9277 | if (ret) |
9b51f66d | 9278 | break; |
564c2b21 PM |
9279 | } |
9280 | ||
dddd3379 TG |
9281 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); |
9282 | parent_ctx->rotate_disable = 0; | |
dddd3379 | 9283 | |
8dc85d54 | 9284 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 | 9285 | |
05cbaa28 | 9286 | if (child_ctx && inherited_all) { |
564c2b21 PM |
9287 | /* |
9288 | * Mark the child context as a clone of the parent | |
9289 | * context, or of whatever the parent is a clone of. | |
c5ed5145 PZ |
9290 | * |
9291 | * Note that if the parent is a clone, the holding of | |
9292 | * parent_ctx->lock avoids it from being uncloned. | |
564c2b21 | 9293 | */ |
c5ed5145 | 9294 | cloned_ctx = parent_ctx->parent_ctx; |
ad3a37de PM |
9295 | if (cloned_ctx) { |
9296 | child_ctx->parent_ctx = cloned_ctx; | |
25346b93 | 9297 | child_ctx->parent_gen = parent_ctx->parent_gen; |
564c2b21 PM |
9298 | } else { |
9299 | child_ctx->parent_ctx = parent_ctx; | |
9300 | child_ctx->parent_gen = parent_ctx->generation; | |
9301 | } | |
9302 | get_ctx(child_ctx->parent_ctx); | |
9b51f66d IM |
9303 | } |
9304 | ||
c5ed5145 | 9305 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); |
d859e29f | 9306 | mutex_unlock(&parent_ctx->mutex); |
6ab423e0 | 9307 | |
25346b93 | 9308 | perf_unpin_context(parent_ctx); |
fe4b04fa | 9309 | put_ctx(parent_ctx); |
ad3a37de | 9310 | |
6ab423e0 | 9311 | return ret; |
9b51f66d IM |
9312 | } |
9313 | ||
8dc85d54 PZ |
9314 | /* |
9315 | * Initialize the perf_event context in task_struct | |
9316 | */ | |
9317 | int perf_event_init_task(struct task_struct *child) | |
9318 | { | |
9319 | int ctxn, ret; | |
9320 | ||
8550d7cb ON |
9321 | memset(child->perf_event_ctxp, 0, sizeof(child->perf_event_ctxp)); |
9322 | mutex_init(&child->perf_event_mutex); | |
9323 | INIT_LIST_HEAD(&child->perf_event_list); | |
9324 | ||
8dc85d54 PZ |
9325 | for_each_task_context_nr(ctxn) { |
9326 | ret = perf_event_init_context(child, ctxn); | |
6c72e350 PZ |
9327 | if (ret) { |
9328 | perf_event_free_task(child); | |
8dc85d54 | 9329 | return ret; |
6c72e350 | 9330 | } |
8dc85d54 PZ |
9331 | } |
9332 | ||
9333 | return 0; | |
9334 | } | |
9335 | ||
220b140b PM |
9336 | static void __init perf_event_init_all_cpus(void) |
9337 | { | |
b28ab83c | 9338 | struct swevent_htable *swhash; |
220b140b | 9339 | int cpu; |
220b140b PM |
9340 | |
9341 | for_each_possible_cpu(cpu) { | |
b28ab83c PZ |
9342 | swhash = &per_cpu(swevent_htable, cpu); |
9343 | mutex_init(&swhash->hlist_mutex); | |
2fde4f94 | 9344 | INIT_LIST_HEAD(&per_cpu(active_ctx_list, cpu)); |
220b140b PM |
9345 | } |
9346 | } | |
9347 | ||
0db0628d | 9348 | static void perf_event_init_cpu(int cpu) |
0793a61d | 9349 | { |
108b02cf | 9350 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
0793a61d | 9351 | |
b28ab83c | 9352 | mutex_lock(&swhash->hlist_mutex); |
059fcd8c | 9353 | if (swhash->hlist_refcount > 0 && !swevent_hlist_deref(swhash)) { |
76e1d904 FW |
9354 | struct swevent_hlist *hlist; |
9355 | ||
b28ab83c PZ |
9356 | hlist = kzalloc_node(sizeof(*hlist), GFP_KERNEL, cpu_to_node(cpu)); |
9357 | WARN_ON(!hlist); | |
9358 | rcu_assign_pointer(swhash->swevent_hlist, hlist); | |
76e1d904 | 9359 | } |
b28ab83c | 9360 | mutex_unlock(&swhash->hlist_mutex); |
0793a61d TG |
9361 | } |
9362 | ||
2965faa5 | 9363 | #if defined CONFIG_HOTPLUG_CPU || defined CONFIG_KEXEC_CORE |
108b02cf | 9364 | static void __perf_event_exit_context(void *__info) |
0793a61d | 9365 | { |
108b02cf | 9366 | struct perf_event_context *ctx = __info; |
fae3fde6 PZ |
9367 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
9368 | struct perf_event *event; | |
0793a61d | 9369 | |
fae3fde6 PZ |
9370 | raw_spin_lock(&ctx->lock); |
9371 | list_for_each_entry(event, &ctx->event_list, event_entry) | |
45a0e07a | 9372 | __perf_remove_from_context(event, cpuctx, ctx, (void *)DETACH_GROUP); |
fae3fde6 | 9373 | raw_spin_unlock(&ctx->lock); |
0793a61d | 9374 | } |
108b02cf PZ |
9375 | |
9376 | static void perf_event_exit_cpu_context(int cpu) | |
9377 | { | |
9378 | struct perf_event_context *ctx; | |
9379 | struct pmu *pmu; | |
9380 | int idx; | |
9381 | ||
9382 | idx = srcu_read_lock(&pmus_srcu); | |
9383 | list_for_each_entry_rcu(pmu, &pmus, entry) { | |
917bdd1c | 9384 | ctx = &per_cpu_ptr(pmu->pmu_cpu_context, cpu)->ctx; |
108b02cf PZ |
9385 | |
9386 | mutex_lock(&ctx->mutex); | |
9387 | smp_call_function_single(cpu, __perf_event_exit_context, ctx, 1); | |
9388 | mutex_unlock(&ctx->mutex); | |
9389 | } | |
9390 | srcu_read_unlock(&pmus_srcu, idx); | |
108b02cf PZ |
9391 | } |
9392 | ||
cdd6c482 | 9393 | static void perf_event_exit_cpu(int cpu) |
0793a61d | 9394 | { |
e3703f8c | 9395 | perf_event_exit_cpu_context(cpu); |
0793a61d TG |
9396 | } |
9397 | #else | |
cdd6c482 | 9398 | static inline void perf_event_exit_cpu(int cpu) { } |
0793a61d TG |
9399 | #endif |
9400 | ||
c277443c PZ |
9401 | static int |
9402 | perf_reboot(struct notifier_block *notifier, unsigned long val, void *v) | |
9403 | { | |
9404 | int cpu; | |
9405 | ||
9406 | for_each_online_cpu(cpu) | |
9407 | perf_event_exit_cpu(cpu); | |
9408 | ||
9409 | return NOTIFY_OK; | |
9410 | } | |
9411 | ||
9412 | /* | |
9413 | * Run the perf reboot notifier at the very last possible moment so that | |
9414 | * the generic watchdog code runs as long as possible. | |
9415 | */ | |
9416 | static struct notifier_block perf_reboot_notifier = { | |
9417 | .notifier_call = perf_reboot, | |
9418 | .priority = INT_MIN, | |
9419 | }; | |
9420 | ||
0db0628d | 9421 | static int |
0793a61d TG |
9422 | perf_cpu_notify(struct notifier_block *self, unsigned long action, void *hcpu) |
9423 | { | |
9424 | unsigned int cpu = (long)hcpu; | |
9425 | ||
4536e4d1 | 9426 | switch (action & ~CPU_TASKS_FROZEN) { |
0793a61d TG |
9427 | |
9428 | case CPU_UP_PREPARE: | |
cdd6c482 | 9429 | perf_event_init_cpu(cpu); |
0793a61d TG |
9430 | break; |
9431 | ||
9432 | case CPU_DOWN_PREPARE: | |
cdd6c482 | 9433 | perf_event_exit_cpu(cpu); |
0793a61d | 9434 | break; |
0793a61d TG |
9435 | default: |
9436 | break; | |
9437 | } | |
9438 | ||
9439 | return NOTIFY_OK; | |
9440 | } | |
9441 | ||
cdd6c482 | 9442 | void __init perf_event_init(void) |
0793a61d | 9443 | { |
3c502e7a JW |
9444 | int ret; |
9445 | ||
2e80a82a PZ |
9446 | idr_init(&pmu_idr); |
9447 | ||
220b140b | 9448 | perf_event_init_all_cpus(); |
b0a873eb | 9449 | init_srcu_struct(&pmus_srcu); |
2e80a82a PZ |
9450 | perf_pmu_register(&perf_swevent, "software", PERF_TYPE_SOFTWARE); |
9451 | perf_pmu_register(&perf_cpu_clock, NULL, -1); | |
9452 | perf_pmu_register(&perf_task_clock, NULL, -1); | |
b0a873eb PZ |
9453 | perf_tp_register(); |
9454 | perf_cpu_notifier(perf_cpu_notify); | |
c277443c | 9455 | register_reboot_notifier(&perf_reboot_notifier); |
3c502e7a JW |
9456 | |
9457 | ret = init_hw_breakpoint(); | |
9458 | WARN(ret, "hw_breakpoint initialization failed with: %d", ret); | |
b2029520 | 9459 | |
b01c3a00 JO |
9460 | /* |
9461 | * Build time assertion that we keep the data_head at the intended | |
9462 | * location. IOW, validation we got the __reserved[] size right. | |
9463 | */ | |
9464 | BUILD_BUG_ON((offsetof(struct perf_event_mmap_page, data_head)) | |
9465 | != 1024); | |
0793a61d | 9466 | } |
abe43400 | 9467 | |
fd979c01 CS |
9468 | ssize_t perf_event_sysfs_show(struct device *dev, struct device_attribute *attr, |
9469 | char *page) | |
9470 | { | |
9471 | struct perf_pmu_events_attr *pmu_attr = | |
9472 | container_of(attr, struct perf_pmu_events_attr, attr); | |
9473 | ||
9474 | if (pmu_attr->event_str) | |
9475 | return sprintf(page, "%s\n", pmu_attr->event_str); | |
9476 | ||
9477 | return 0; | |
9478 | } | |
675965b0 | 9479 | EXPORT_SYMBOL_GPL(perf_event_sysfs_show); |
fd979c01 | 9480 | |
abe43400 PZ |
9481 | static int __init perf_event_sysfs_init(void) |
9482 | { | |
9483 | struct pmu *pmu; | |
9484 | int ret; | |
9485 | ||
9486 | mutex_lock(&pmus_lock); | |
9487 | ||
9488 | ret = bus_register(&pmu_bus); | |
9489 | if (ret) | |
9490 | goto unlock; | |
9491 | ||
9492 | list_for_each_entry(pmu, &pmus, entry) { | |
9493 | if (!pmu->name || pmu->type < 0) | |
9494 | continue; | |
9495 | ||
9496 | ret = pmu_dev_alloc(pmu); | |
9497 | WARN(ret, "Failed to register pmu: %s, reason %d\n", pmu->name, ret); | |
9498 | } | |
9499 | pmu_bus_running = 1; | |
9500 | ret = 0; | |
9501 | ||
9502 | unlock: | |
9503 | mutex_unlock(&pmus_lock); | |
9504 | ||
9505 | return ret; | |
9506 | } | |
9507 | device_initcall(perf_event_sysfs_init); | |
e5d1367f SE |
9508 | |
9509 | #ifdef CONFIG_CGROUP_PERF | |
eb95419b TH |
9510 | static struct cgroup_subsys_state * |
9511 | perf_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) | |
e5d1367f SE |
9512 | { |
9513 | struct perf_cgroup *jc; | |
e5d1367f | 9514 | |
1b15d055 | 9515 | jc = kzalloc(sizeof(*jc), GFP_KERNEL); |
e5d1367f SE |
9516 | if (!jc) |
9517 | return ERR_PTR(-ENOMEM); | |
9518 | ||
e5d1367f SE |
9519 | jc->info = alloc_percpu(struct perf_cgroup_info); |
9520 | if (!jc->info) { | |
9521 | kfree(jc); | |
9522 | return ERR_PTR(-ENOMEM); | |
9523 | } | |
9524 | ||
e5d1367f SE |
9525 | return &jc->css; |
9526 | } | |
9527 | ||
eb95419b | 9528 | static void perf_cgroup_css_free(struct cgroup_subsys_state *css) |
e5d1367f | 9529 | { |
eb95419b TH |
9530 | struct perf_cgroup *jc = container_of(css, struct perf_cgroup, css); |
9531 | ||
e5d1367f SE |
9532 | free_percpu(jc->info); |
9533 | kfree(jc); | |
9534 | } | |
9535 | ||
9536 | static int __perf_cgroup_move(void *info) | |
9537 | { | |
9538 | struct task_struct *task = info; | |
ddaaf4e2 | 9539 | rcu_read_lock(); |
e5d1367f | 9540 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT | PERF_CGROUP_SWIN); |
ddaaf4e2 | 9541 | rcu_read_unlock(); |
e5d1367f SE |
9542 | return 0; |
9543 | } | |
9544 | ||
1f7dd3e5 | 9545 | static void perf_cgroup_attach(struct cgroup_taskset *tset) |
e5d1367f | 9546 | { |
bb9d97b6 | 9547 | struct task_struct *task; |
1f7dd3e5 | 9548 | struct cgroup_subsys_state *css; |
bb9d97b6 | 9549 | |
1f7dd3e5 | 9550 | cgroup_taskset_for_each(task, css, tset) |
bb9d97b6 | 9551 | task_function_call(task, __perf_cgroup_move, task); |
e5d1367f SE |
9552 | } |
9553 | ||
073219e9 | 9554 | struct cgroup_subsys perf_event_cgrp_subsys = { |
92fb9748 TH |
9555 | .css_alloc = perf_cgroup_css_alloc, |
9556 | .css_free = perf_cgroup_css_free, | |
bb9d97b6 | 9557 | .attach = perf_cgroup_attach, |
e5d1367f SE |
9558 | }; |
9559 | #endif /* CONFIG_CGROUP_PERF */ |