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Commit | Line | Data |
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0793a61d | 1 | /* |
57c0c15b | 2 | * Performance events core code: |
0793a61d | 3 | * |
98144511 | 4 | * Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de> |
e7e7ee2e | 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> | |
375637bc AS |
47 | #include <linux/namei.h> |
48 | #include <linux/parser.h> | |
0793a61d | 49 | |
76369139 FW |
50 | #include "internal.h" |
51 | ||
4e193bd4 TB |
52 | #include <asm/irq_regs.h> |
53 | ||
272325c4 PZ |
54 | typedef int (*remote_function_f)(void *); |
55 | ||
fe4b04fa | 56 | struct remote_function_call { |
e7e7ee2e | 57 | struct task_struct *p; |
272325c4 | 58 | remote_function_f func; |
e7e7ee2e IM |
59 | void *info; |
60 | int ret; | |
fe4b04fa PZ |
61 | }; |
62 | ||
63 | static void remote_function(void *data) | |
64 | { | |
65 | struct remote_function_call *tfc = data; | |
66 | struct task_struct *p = tfc->p; | |
67 | ||
68 | if (p) { | |
0da4cf3e PZ |
69 | /* -EAGAIN */ |
70 | if (task_cpu(p) != smp_processor_id()) | |
71 | return; | |
72 | ||
73 | /* | |
74 | * Now that we're on right CPU with IRQs disabled, we can test | |
75 | * if we hit the right task without races. | |
76 | */ | |
77 | ||
78 | tfc->ret = -ESRCH; /* No such (running) process */ | |
79 | if (p != current) | |
fe4b04fa PZ |
80 | return; |
81 | } | |
82 | ||
83 | tfc->ret = tfc->func(tfc->info); | |
84 | } | |
85 | ||
86 | /** | |
87 | * task_function_call - call a function on the cpu on which a task runs | |
88 | * @p: the task to evaluate | |
89 | * @func: the function to be called | |
90 | * @info: the function call argument | |
91 | * | |
92 | * Calls the function @func when the task is currently running. This might | |
93 | * be on the current CPU, which just calls the function directly | |
94 | * | |
95 | * returns: @func return value, or | |
96 | * -ESRCH - when the process isn't running | |
97 | * -EAGAIN - when the process moved away | |
98 | */ | |
99 | static int | |
272325c4 | 100 | task_function_call(struct task_struct *p, remote_function_f func, void *info) |
fe4b04fa PZ |
101 | { |
102 | struct remote_function_call data = { | |
e7e7ee2e IM |
103 | .p = p, |
104 | .func = func, | |
105 | .info = info, | |
0da4cf3e | 106 | .ret = -EAGAIN, |
fe4b04fa | 107 | }; |
0da4cf3e | 108 | int ret; |
fe4b04fa | 109 | |
0da4cf3e PZ |
110 | do { |
111 | ret = smp_call_function_single(task_cpu(p), remote_function, &data, 1); | |
112 | if (!ret) | |
113 | ret = data.ret; | |
114 | } while (ret == -EAGAIN); | |
fe4b04fa | 115 | |
0da4cf3e | 116 | return ret; |
fe4b04fa PZ |
117 | } |
118 | ||
119 | /** | |
120 | * cpu_function_call - call a function on the cpu | |
121 | * @func: the function to be called | |
122 | * @info: the function call argument | |
123 | * | |
124 | * Calls the function @func on the remote cpu. | |
125 | * | |
126 | * returns: @func return value or -ENXIO when the cpu is offline | |
127 | */ | |
272325c4 | 128 | static int cpu_function_call(int cpu, remote_function_f func, void *info) |
fe4b04fa PZ |
129 | { |
130 | struct remote_function_call data = { | |
e7e7ee2e IM |
131 | .p = NULL, |
132 | .func = func, | |
133 | .info = info, | |
134 | .ret = -ENXIO, /* No such CPU */ | |
fe4b04fa PZ |
135 | }; |
136 | ||
137 | smp_call_function_single(cpu, remote_function, &data, 1); | |
138 | ||
139 | return data.ret; | |
140 | } | |
141 | ||
fae3fde6 PZ |
142 | static inline struct perf_cpu_context * |
143 | __get_cpu_context(struct perf_event_context *ctx) | |
144 | { | |
145 | return this_cpu_ptr(ctx->pmu->pmu_cpu_context); | |
146 | } | |
147 | ||
148 | static void perf_ctx_lock(struct perf_cpu_context *cpuctx, | |
149 | struct perf_event_context *ctx) | |
0017960f | 150 | { |
fae3fde6 PZ |
151 | raw_spin_lock(&cpuctx->ctx.lock); |
152 | if (ctx) | |
153 | raw_spin_lock(&ctx->lock); | |
154 | } | |
155 | ||
156 | static void perf_ctx_unlock(struct perf_cpu_context *cpuctx, | |
157 | struct perf_event_context *ctx) | |
158 | { | |
159 | if (ctx) | |
160 | raw_spin_unlock(&ctx->lock); | |
161 | raw_spin_unlock(&cpuctx->ctx.lock); | |
162 | } | |
163 | ||
63b6da39 PZ |
164 | #define TASK_TOMBSTONE ((void *)-1L) |
165 | ||
166 | static bool is_kernel_event(struct perf_event *event) | |
167 | { | |
f47c02c0 | 168 | return READ_ONCE(event->owner) == TASK_TOMBSTONE; |
63b6da39 PZ |
169 | } |
170 | ||
39a43640 PZ |
171 | /* |
172 | * On task ctx scheduling... | |
173 | * | |
174 | * When !ctx->nr_events a task context will not be scheduled. This means | |
175 | * we can disable the scheduler hooks (for performance) without leaving | |
176 | * pending task ctx state. | |
177 | * | |
178 | * This however results in two special cases: | |
179 | * | |
180 | * - removing the last event from a task ctx; this is relatively straight | |
181 | * forward and is done in __perf_remove_from_context. | |
182 | * | |
183 | * - adding the first event to a task ctx; this is tricky because we cannot | |
184 | * rely on ctx->is_active and therefore cannot use event_function_call(). | |
185 | * See perf_install_in_context(). | |
186 | * | |
39a43640 PZ |
187 | * If ctx->nr_events, then ctx->is_active and cpuctx->task_ctx are set. |
188 | */ | |
189 | ||
fae3fde6 PZ |
190 | typedef void (*event_f)(struct perf_event *, struct perf_cpu_context *, |
191 | struct perf_event_context *, void *); | |
192 | ||
193 | struct event_function_struct { | |
194 | struct perf_event *event; | |
195 | event_f func; | |
196 | void *data; | |
197 | }; | |
198 | ||
199 | static int event_function(void *info) | |
200 | { | |
201 | struct event_function_struct *efs = info; | |
202 | struct perf_event *event = efs->event; | |
0017960f | 203 | struct perf_event_context *ctx = event->ctx; |
fae3fde6 PZ |
204 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
205 | struct perf_event_context *task_ctx = cpuctx->task_ctx; | |
63b6da39 | 206 | int ret = 0; |
fae3fde6 PZ |
207 | |
208 | WARN_ON_ONCE(!irqs_disabled()); | |
209 | ||
63b6da39 | 210 | perf_ctx_lock(cpuctx, task_ctx); |
fae3fde6 PZ |
211 | /* |
212 | * Since we do the IPI call without holding ctx->lock things can have | |
213 | * changed, double check we hit the task we set out to hit. | |
fae3fde6 PZ |
214 | */ |
215 | if (ctx->task) { | |
63b6da39 | 216 | if (ctx->task != current) { |
0da4cf3e | 217 | ret = -ESRCH; |
63b6da39 PZ |
218 | goto unlock; |
219 | } | |
fae3fde6 | 220 | |
fae3fde6 PZ |
221 | /* |
222 | * We only use event_function_call() on established contexts, | |
223 | * and event_function() is only ever called when active (or | |
224 | * rather, we'll have bailed in task_function_call() or the | |
225 | * above ctx->task != current test), therefore we must have | |
226 | * ctx->is_active here. | |
227 | */ | |
228 | WARN_ON_ONCE(!ctx->is_active); | |
229 | /* | |
230 | * And since we have ctx->is_active, cpuctx->task_ctx must | |
231 | * match. | |
232 | */ | |
63b6da39 PZ |
233 | WARN_ON_ONCE(task_ctx != ctx); |
234 | } else { | |
235 | WARN_ON_ONCE(&cpuctx->ctx != ctx); | |
fae3fde6 | 236 | } |
63b6da39 | 237 | |
fae3fde6 | 238 | efs->func(event, cpuctx, ctx, efs->data); |
63b6da39 | 239 | unlock: |
fae3fde6 PZ |
240 | perf_ctx_unlock(cpuctx, task_ctx); |
241 | ||
63b6da39 | 242 | return ret; |
fae3fde6 PZ |
243 | } |
244 | ||
fae3fde6 | 245 | static void event_function_call(struct perf_event *event, event_f func, void *data) |
0017960f PZ |
246 | { |
247 | struct perf_event_context *ctx = event->ctx; | |
63b6da39 | 248 | struct task_struct *task = READ_ONCE(ctx->task); /* verified in event_function */ |
fae3fde6 PZ |
249 | struct event_function_struct efs = { |
250 | .event = event, | |
251 | .func = func, | |
252 | .data = data, | |
253 | }; | |
0017960f | 254 | |
c97f4736 PZ |
255 | if (!event->parent) { |
256 | /* | |
257 | * If this is a !child event, we must hold ctx::mutex to | |
258 | * stabilize the the event->ctx relation. See | |
259 | * perf_event_ctx_lock(). | |
260 | */ | |
261 | lockdep_assert_held(&ctx->mutex); | |
262 | } | |
0017960f PZ |
263 | |
264 | if (!task) { | |
fae3fde6 | 265 | cpu_function_call(event->cpu, event_function, &efs); |
0017960f PZ |
266 | return; |
267 | } | |
268 | ||
63b6da39 PZ |
269 | if (task == TASK_TOMBSTONE) |
270 | return; | |
271 | ||
a096309b | 272 | again: |
fae3fde6 | 273 | if (!task_function_call(task, event_function, &efs)) |
0017960f PZ |
274 | return; |
275 | ||
276 | raw_spin_lock_irq(&ctx->lock); | |
63b6da39 PZ |
277 | /* |
278 | * Reload the task pointer, it might have been changed by | |
279 | * a concurrent perf_event_context_sched_out(). | |
280 | */ | |
281 | task = ctx->task; | |
a096309b PZ |
282 | if (task == TASK_TOMBSTONE) { |
283 | raw_spin_unlock_irq(&ctx->lock); | |
284 | return; | |
0017960f | 285 | } |
a096309b PZ |
286 | if (ctx->is_active) { |
287 | raw_spin_unlock_irq(&ctx->lock); | |
288 | goto again; | |
289 | } | |
290 | func(event, NULL, ctx, data); | |
0017960f PZ |
291 | raw_spin_unlock_irq(&ctx->lock); |
292 | } | |
293 | ||
cca20946 PZ |
294 | /* |
295 | * Similar to event_function_call() + event_function(), but hard assumes IRQs | |
296 | * are already disabled and we're on the right CPU. | |
297 | */ | |
298 | static void event_function_local(struct perf_event *event, event_f func, void *data) | |
299 | { | |
300 | struct perf_event_context *ctx = event->ctx; | |
301 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
302 | struct task_struct *task = READ_ONCE(ctx->task); | |
303 | struct perf_event_context *task_ctx = NULL; | |
304 | ||
305 | WARN_ON_ONCE(!irqs_disabled()); | |
306 | ||
307 | if (task) { | |
308 | if (task == TASK_TOMBSTONE) | |
309 | return; | |
310 | ||
311 | task_ctx = ctx; | |
312 | } | |
313 | ||
314 | perf_ctx_lock(cpuctx, task_ctx); | |
315 | ||
316 | task = ctx->task; | |
317 | if (task == TASK_TOMBSTONE) | |
318 | goto unlock; | |
319 | ||
320 | if (task) { | |
321 | /* | |
322 | * We must be either inactive or active and the right task, | |
323 | * otherwise we're screwed, since we cannot IPI to somewhere | |
324 | * else. | |
325 | */ | |
326 | if (ctx->is_active) { | |
327 | if (WARN_ON_ONCE(task != current)) | |
328 | goto unlock; | |
329 | ||
330 | if (WARN_ON_ONCE(cpuctx->task_ctx != ctx)) | |
331 | goto unlock; | |
332 | } | |
333 | } else { | |
334 | WARN_ON_ONCE(&cpuctx->ctx != ctx); | |
335 | } | |
336 | ||
337 | func(event, cpuctx, ctx, data); | |
338 | unlock: | |
339 | perf_ctx_unlock(cpuctx, task_ctx); | |
340 | } | |
341 | ||
e5d1367f SE |
342 | #define PERF_FLAG_ALL (PERF_FLAG_FD_NO_GROUP |\ |
343 | PERF_FLAG_FD_OUTPUT |\ | |
a21b0b35 YD |
344 | PERF_FLAG_PID_CGROUP |\ |
345 | PERF_FLAG_FD_CLOEXEC) | |
e5d1367f | 346 | |
bce38cd5 SE |
347 | /* |
348 | * branch priv levels that need permission checks | |
349 | */ | |
350 | #define PERF_SAMPLE_BRANCH_PERM_PLM \ | |
351 | (PERF_SAMPLE_BRANCH_KERNEL |\ | |
352 | PERF_SAMPLE_BRANCH_HV) | |
353 | ||
0b3fcf17 SE |
354 | enum event_type_t { |
355 | EVENT_FLEXIBLE = 0x1, | |
356 | EVENT_PINNED = 0x2, | |
3cbaa590 | 357 | EVENT_TIME = 0x4, |
0b3fcf17 SE |
358 | EVENT_ALL = EVENT_FLEXIBLE | EVENT_PINNED, |
359 | }; | |
360 | ||
e5d1367f SE |
361 | /* |
362 | * perf_sched_events : >0 events exist | |
363 | * perf_cgroup_events: >0 per-cpu cgroup events exist on this cpu | |
364 | */ | |
9107c89e PZ |
365 | |
366 | static void perf_sched_delayed(struct work_struct *work); | |
367 | DEFINE_STATIC_KEY_FALSE(perf_sched_events); | |
368 | static DECLARE_DELAYED_WORK(perf_sched_work, perf_sched_delayed); | |
369 | static DEFINE_MUTEX(perf_sched_mutex); | |
370 | static atomic_t perf_sched_count; | |
371 | ||
e5d1367f | 372 | static DEFINE_PER_CPU(atomic_t, perf_cgroup_events); |
ba532500 | 373 | static DEFINE_PER_CPU(int, perf_sched_cb_usages); |
f2fb6bef | 374 | static DEFINE_PER_CPU(struct pmu_event_list, pmu_sb_events); |
e5d1367f | 375 | |
cdd6c482 IM |
376 | static atomic_t nr_mmap_events __read_mostly; |
377 | static atomic_t nr_comm_events __read_mostly; | |
378 | static atomic_t nr_task_events __read_mostly; | |
948b26b6 | 379 | static atomic_t nr_freq_events __read_mostly; |
45ac1403 | 380 | static atomic_t nr_switch_events __read_mostly; |
9ee318a7 | 381 | |
108b02cf PZ |
382 | static LIST_HEAD(pmus); |
383 | static DEFINE_MUTEX(pmus_lock); | |
384 | static struct srcu_struct pmus_srcu; | |
385 | ||
0764771d | 386 | /* |
cdd6c482 | 387 | * perf event paranoia level: |
0fbdea19 IM |
388 | * -1 - not paranoid at all |
389 | * 0 - disallow raw tracepoint access for unpriv | |
cdd6c482 | 390 | * 1 - disallow cpu events for unpriv |
0fbdea19 | 391 | * 2 - disallow kernel profiling for unpriv |
0764771d | 392 | */ |
0161028b | 393 | int sysctl_perf_event_paranoid __read_mostly = 2; |
0764771d | 394 | |
20443384 FW |
395 | /* Minimum for 512 kiB + 1 user control page */ |
396 | int sysctl_perf_event_mlock __read_mostly = 512 + (PAGE_SIZE / 1024); /* 'free' kiB per user */ | |
df58ab24 PZ |
397 | |
398 | /* | |
cdd6c482 | 399 | * max perf event sample rate |
df58ab24 | 400 | */ |
14c63f17 DH |
401 | #define DEFAULT_MAX_SAMPLE_RATE 100000 |
402 | #define DEFAULT_SAMPLE_PERIOD_NS (NSEC_PER_SEC / DEFAULT_MAX_SAMPLE_RATE) | |
403 | #define DEFAULT_CPU_TIME_MAX_PERCENT 25 | |
404 | ||
405 | int sysctl_perf_event_sample_rate __read_mostly = DEFAULT_MAX_SAMPLE_RATE; | |
406 | ||
407 | static int max_samples_per_tick __read_mostly = DIV_ROUND_UP(DEFAULT_MAX_SAMPLE_RATE, HZ); | |
408 | static int perf_sample_period_ns __read_mostly = DEFAULT_SAMPLE_PERIOD_NS; | |
409 | ||
d9494cb4 PZ |
410 | static int perf_sample_allowed_ns __read_mostly = |
411 | DEFAULT_SAMPLE_PERIOD_NS * DEFAULT_CPU_TIME_MAX_PERCENT / 100; | |
14c63f17 | 412 | |
18ab2cd3 | 413 | static void update_perf_cpu_limits(void) |
14c63f17 DH |
414 | { |
415 | u64 tmp = perf_sample_period_ns; | |
416 | ||
417 | tmp *= sysctl_perf_cpu_time_max_percent; | |
91a612ee PZ |
418 | tmp = div_u64(tmp, 100); |
419 | if (!tmp) | |
420 | tmp = 1; | |
421 | ||
422 | WRITE_ONCE(perf_sample_allowed_ns, tmp); | |
14c63f17 | 423 | } |
163ec435 | 424 | |
9e630205 SE |
425 | static int perf_rotate_context(struct perf_cpu_context *cpuctx); |
426 | ||
163ec435 PZ |
427 | int perf_proc_update_handler(struct ctl_table *table, int write, |
428 | void __user *buffer, size_t *lenp, | |
429 | loff_t *ppos) | |
430 | { | |
723478c8 | 431 | int ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
163ec435 PZ |
432 | |
433 | if (ret || !write) | |
434 | return ret; | |
435 | ||
ab7fdefb KL |
436 | /* |
437 | * If throttling is disabled don't allow the write: | |
438 | */ | |
439 | if (sysctl_perf_cpu_time_max_percent == 100 || | |
440 | sysctl_perf_cpu_time_max_percent == 0) | |
441 | return -EINVAL; | |
442 | ||
163ec435 | 443 | max_samples_per_tick = DIV_ROUND_UP(sysctl_perf_event_sample_rate, HZ); |
14c63f17 DH |
444 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; |
445 | update_perf_cpu_limits(); | |
446 | ||
447 | return 0; | |
448 | } | |
449 | ||
450 | int sysctl_perf_cpu_time_max_percent __read_mostly = DEFAULT_CPU_TIME_MAX_PERCENT; | |
451 | ||
452 | int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write, | |
453 | void __user *buffer, size_t *lenp, | |
454 | loff_t *ppos) | |
455 | { | |
456 | int ret = proc_dointvec(table, write, buffer, lenp, ppos); | |
457 | ||
458 | if (ret || !write) | |
459 | return ret; | |
460 | ||
b303e7c1 PZ |
461 | if (sysctl_perf_cpu_time_max_percent == 100 || |
462 | sysctl_perf_cpu_time_max_percent == 0) { | |
91a612ee PZ |
463 | printk(KERN_WARNING |
464 | "perf: Dynamic interrupt throttling disabled, can hang your system!\n"); | |
465 | WRITE_ONCE(perf_sample_allowed_ns, 0); | |
466 | } else { | |
467 | update_perf_cpu_limits(); | |
468 | } | |
163ec435 PZ |
469 | |
470 | return 0; | |
471 | } | |
1ccd1549 | 472 | |
14c63f17 DH |
473 | /* |
474 | * perf samples are done in some very critical code paths (NMIs). | |
475 | * If they take too much CPU time, the system can lock up and not | |
476 | * get any real work done. This will drop the sample rate when | |
477 | * we detect that events are taking too long. | |
478 | */ | |
479 | #define NR_ACCUMULATED_SAMPLES 128 | |
d9494cb4 | 480 | static DEFINE_PER_CPU(u64, running_sample_length); |
14c63f17 | 481 | |
91a612ee PZ |
482 | static u64 __report_avg; |
483 | static u64 __report_allowed; | |
484 | ||
6a02ad66 | 485 | static void perf_duration_warn(struct irq_work *w) |
14c63f17 | 486 | { |
0d87d7ec | 487 | printk_ratelimited(KERN_INFO |
91a612ee PZ |
488 | "perf: interrupt took too long (%lld > %lld), lowering " |
489 | "kernel.perf_event_max_sample_rate to %d\n", | |
490 | __report_avg, __report_allowed, | |
491 | sysctl_perf_event_sample_rate); | |
6a02ad66 PZ |
492 | } |
493 | ||
494 | static DEFINE_IRQ_WORK(perf_duration_work, perf_duration_warn); | |
495 | ||
496 | void perf_sample_event_took(u64 sample_len_ns) | |
497 | { | |
91a612ee PZ |
498 | u64 max_len = READ_ONCE(perf_sample_allowed_ns); |
499 | u64 running_len; | |
500 | u64 avg_len; | |
501 | u32 max; | |
14c63f17 | 502 | |
91a612ee | 503 | if (max_len == 0) |
14c63f17 DH |
504 | return; |
505 | ||
91a612ee PZ |
506 | /* Decay the counter by 1 average sample. */ |
507 | running_len = __this_cpu_read(running_sample_length); | |
508 | running_len -= running_len/NR_ACCUMULATED_SAMPLES; | |
509 | running_len += sample_len_ns; | |
510 | __this_cpu_write(running_sample_length, running_len); | |
14c63f17 DH |
511 | |
512 | /* | |
91a612ee PZ |
513 | * Note: this will be biased artifically low until we have |
514 | * seen NR_ACCUMULATED_SAMPLES. Doing it this way keeps us | |
14c63f17 DH |
515 | * from having to maintain a count. |
516 | */ | |
91a612ee PZ |
517 | avg_len = running_len/NR_ACCUMULATED_SAMPLES; |
518 | if (avg_len <= max_len) | |
14c63f17 DH |
519 | return; |
520 | ||
91a612ee PZ |
521 | __report_avg = avg_len; |
522 | __report_allowed = max_len; | |
14c63f17 | 523 | |
91a612ee PZ |
524 | /* |
525 | * Compute a throttle threshold 25% below the current duration. | |
526 | */ | |
527 | avg_len += avg_len / 4; | |
528 | max = (TICK_NSEC / 100) * sysctl_perf_cpu_time_max_percent; | |
529 | if (avg_len < max) | |
530 | max /= (u32)avg_len; | |
531 | else | |
532 | max = 1; | |
14c63f17 | 533 | |
91a612ee PZ |
534 | WRITE_ONCE(perf_sample_allowed_ns, avg_len); |
535 | WRITE_ONCE(max_samples_per_tick, max); | |
536 | ||
537 | sysctl_perf_event_sample_rate = max * HZ; | |
538 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; | |
6a02ad66 | 539 | |
cd578abb | 540 | if (!irq_work_queue(&perf_duration_work)) { |
91a612ee | 541 | early_printk("perf: interrupt took too long (%lld > %lld), lowering " |
cd578abb | 542 | "kernel.perf_event_max_sample_rate to %d\n", |
91a612ee | 543 | __report_avg, __report_allowed, |
cd578abb PZ |
544 | sysctl_perf_event_sample_rate); |
545 | } | |
14c63f17 DH |
546 | } |
547 | ||
cdd6c482 | 548 | static atomic64_t perf_event_id; |
a96bbc16 | 549 | |
0b3fcf17 SE |
550 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, |
551 | enum event_type_t event_type); | |
552 | ||
553 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
554 | enum event_type_t event_type, |
555 | struct task_struct *task); | |
556 | ||
557 | static void update_context_time(struct perf_event_context *ctx); | |
558 | static u64 perf_event_time(struct perf_event *event); | |
0b3fcf17 | 559 | |
cdd6c482 | 560 | void __weak perf_event_print_debug(void) { } |
0793a61d | 561 | |
84c79910 | 562 | extern __weak const char *perf_pmu_name(void) |
0793a61d | 563 | { |
84c79910 | 564 | return "pmu"; |
0793a61d TG |
565 | } |
566 | ||
0b3fcf17 SE |
567 | static inline u64 perf_clock(void) |
568 | { | |
569 | return local_clock(); | |
570 | } | |
571 | ||
34f43927 PZ |
572 | static inline u64 perf_event_clock(struct perf_event *event) |
573 | { | |
574 | return event->clock(); | |
575 | } | |
576 | ||
e5d1367f SE |
577 | #ifdef CONFIG_CGROUP_PERF |
578 | ||
e5d1367f SE |
579 | static inline bool |
580 | perf_cgroup_match(struct perf_event *event) | |
581 | { | |
582 | struct perf_event_context *ctx = event->ctx; | |
583 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
584 | ||
ef824fa1 TH |
585 | /* @event doesn't care about cgroup */ |
586 | if (!event->cgrp) | |
587 | return true; | |
588 | ||
589 | /* wants specific cgroup scope but @cpuctx isn't associated with any */ | |
590 | if (!cpuctx->cgrp) | |
591 | return false; | |
592 | ||
593 | /* | |
594 | * Cgroup scoping is recursive. An event enabled for a cgroup is | |
595 | * also enabled for all its descendant cgroups. If @cpuctx's | |
596 | * cgroup is a descendant of @event's (the test covers identity | |
597 | * case), it's a match. | |
598 | */ | |
599 | return cgroup_is_descendant(cpuctx->cgrp->css.cgroup, | |
600 | event->cgrp->css.cgroup); | |
e5d1367f SE |
601 | } |
602 | ||
e5d1367f SE |
603 | static inline void perf_detach_cgroup(struct perf_event *event) |
604 | { | |
4e2ba650 | 605 | css_put(&event->cgrp->css); |
e5d1367f SE |
606 | event->cgrp = NULL; |
607 | } | |
608 | ||
609 | static inline int is_cgroup_event(struct perf_event *event) | |
610 | { | |
611 | return event->cgrp != NULL; | |
612 | } | |
613 | ||
614 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
615 | { | |
616 | struct perf_cgroup_info *t; | |
617 | ||
618 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
619 | return t->time; | |
620 | } | |
621 | ||
622 | static inline void __update_cgrp_time(struct perf_cgroup *cgrp) | |
623 | { | |
624 | struct perf_cgroup_info *info; | |
625 | u64 now; | |
626 | ||
627 | now = perf_clock(); | |
628 | ||
629 | info = this_cpu_ptr(cgrp->info); | |
630 | ||
631 | info->time += now - info->timestamp; | |
632 | info->timestamp = now; | |
633 | } | |
634 | ||
635 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
636 | { | |
637 | struct perf_cgroup *cgrp_out = cpuctx->cgrp; | |
638 | if (cgrp_out) | |
639 | __update_cgrp_time(cgrp_out); | |
640 | } | |
641 | ||
642 | static inline void update_cgrp_time_from_event(struct perf_event *event) | |
643 | { | |
3f7cce3c SE |
644 | struct perf_cgroup *cgrp; |
645 | ||
e5d1367f | 646 | /* |
3f7cce3c SE |
647 | * ensure we access cgroup data only when needed and |
648 | * when we know the cgroup is pinned (css_get) | |
e5d1367f | 649 | */ |
3f7cce3c | 650 | if (!is_cgroup_event(event)) |
e5d1367f SE |
651 | return; |
652 | ||
614e4c4e | 653 | cgrp = perf_cgroup_from_task(current, event->ctx); |
3f7cce3c SE |
654 | /* |
655 | * Do not update time when cgroup is not active | |
656 | */ | |
657 | if (cgrp == event->cgrp) | |
658 | __update_cgrp_time(event->cgrp); | |
e5d1367f SE |
659 | } |
660 | ||
661 | static inline void | |
3f7cce3c SE |
662 | perf_cgroup_set_timestamp(struct task_struct *task, |
663 | struct perf_event_context *ctx) | |
e5d1367f SE |
664 | { |
665 | struct perf_cgroup *cgrp; | |
666 | struct perf_cgroup_info *info; | |
667 | ||
3f7cce3c SE |
668 | /* |
669 | * ctx->lock held by caller | |
670 | * ensure we do not access cgroup data | |
671 | * unless we have the cgroup pinned (css_get) | |
672 | */ | |
673 | if (!task || !ctx->nr_cgroups) | |
e5d1367f SE |
674 | return; |
675 | ||
614e4c4e | 676 | cgrp = perf_cgroup_from_task(task, ctx); |
e5d1367f | 677 | info = this_cpu_ptr(cgrp->info); |
3f7cce3c | 678 | info->timestamp = ctx->timestamp; |
e5d1367f SE |
679 | } |
680 | ||
058fe1c0 DCC |
681 | static DEFINE_PER_CPU(struct list_head, cgrp_cpuctx_list); |
682 | ||
e5d1367f SE |
683 | #define PERF_CGROUP_SWOUT 0x1 /* cgroup switch out every event */ |
684 | #define PERF_CGROUP_SWIN 0x2 /* cgroup switch in events based on task */ | |
685 | ||
686 | /* | |
687 | * reschedule events based on the cgroup constraint of task. | |
688 | * | |
689 | * mode SWOUT : schedule out everything | |
690 | * mode SWIN : schedule in based on cgroup for next | |
691 | */ | |
18ab2cd3 | 692 | static void perf_cgroup_switch(struct task_struct *task, int mode) |
e5d1367f SE |
693 | { |
694 | struct perf_cpu_context *cpuctx; | |
058fe1c0 | 695 | struct list_head *list; |
e5d1367f SE |
696 | unsigned long flags; |
697 | ||
698 | /* | |
058fe1c0 DCC |
699 | * Disable interrupts and preemption to avoid this CPU's |
700 | * cgrp_cpuctx_entry to change under us. | |
e5d1367f SE |
701 | */ |
702 | local_irq_save(flags); | |
703 | ||
058fe1c0 DCC |
704 | list = this_cpu_ptr(&cgrp_cpuctx_list); |
705 | list_for_each_entry(cpuctx, list, cgrp_cpuctx_entry) { | |
706 | WARN_ON_ONCE(cpuctx->ctx.nr_cgroups == 0); | |
e5d1367f | 707 | |
058fe1c0 DCC |
708 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
709 | perf_pmu_disable(cpuctx->ctx.pmu); | |
e5d1367f | 710 | |
058fe1c0 DCC |
711 | if (mode & PERF_CGROUP_SWOUT) { |
712 | cpu_ctx_sched_out(cpuctx, EVENT_ALL); | |
713 | /* | |
714 | * must not be done before ctxswout due | |
715 | * to event_filter_match() in event_sched_out() | |
716 | */ | |
717 | cpuctx->cgrp = NULL; | |
718 | } | |
e5d1367f | 719 | |
058fe1c0 DCC |
720 | if (mode & PERF_CGROUP_SWIN) { |
721 | WARN_ON_ONCE(cpuctx->cgrp); | |
722 | /* | |
723 | * set cgrp before ctxsw in to allow | |
724 | * event_filter_match() to not have to pass | |
725 | * task around | |
726 | * we pass the cpuctx->ctx to perf_cgroup_from_task() | |
727 | * because cgorup events are only per-cpu | |
728 | */ | |
729 | cpuctx->cgrp = perf_cgroup_from_task(task, | |
730 | &cpuctx->ctx); | |
731 | cpu_ctx_sched_in(cpuctx, EVENT_ALL, task); | |
e5d1367f | 732 | } |
058fe1c0 DCC |
733 | perf_pmu_enable(cpuctx->ctx.pmu); |
734 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
e5d1367f SE |
735 | } |
736 | ||
e5d1367f SE |
737 | local_irq_restore(flags); |
738 | } | |
739 | ||
a8d757ef SE |
740 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
741 | struct task_struct *next) | |
e5d1367f | 742 | { |
a8d757ef SE |
743 | struct perf_cgroup *cgrp1; |
744 | struct perf_cgroup *cgrp2 = NULL; | |
745 | ||
ddaaf4e2 | 746 | rcu_read_lock(); |
a8d757ef SE |
747 | /* |
748 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
749 | * we do not need to pass the ctx here because we know |
750 | * we are holding the rcu lock | |
a8d757ef | 751 | */ |
614e4c4e | 752 | cgrp1 = perf_cgroup_from_task(task, NULL); |
70a01657 | 753 | cgrp2 = perf_cgroup_from_task(next, NULL); |
a8d757ef SE |
754 | |
755 | /* | |
756 | * only schedule out current cgroup events if we know | |
757 | * that we are switching to a different cgroup. Otherwise, | |
758 | * do no touch the cgroup events. | |
759 | */ | |
760 | if (cgrp1 != cgrp2) | |
761 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT); | |
ddaaf4e2 SE |
762 | |
763 | rcu_read_unlock(); | |
e5d1367f SE |
764 | } |
765 | ||
a8d757ef SE |
766 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
767 | struct task_struct *task) | |
e5d1367f | 768 | { |
a8d757ef SE |
769 | struct perf_cgroup *cgrp1; |
770 | struct perf_cgroup *cgrp2 = NULL; | |
771 | ||
ddaaf4e2 | 772 | rcu_read_lock(); |
a8d757ef SE |
773 | /* |
774 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
775 | * we do not need to pass the ctx here because we know |
776 | * we are holding the rcu lock | |
a8d757ef | 777 | */ |
614e4c4e | 778 | cgrp1 = perf_cgroup_from_task(task, NULL); |
614e4c4e | 779 | cgrp2 = perf_cgroup_from_task(prev, NULL); |
a8d757ef SE |
780 | |
781 | /* | |
782 | * only need to schedule in cgroup events if we are changing | |
783 | * cgroup during ctxsw. Cgroup events were not scheduled | |
784 | * out of ctxsw out if that was not the case. | |
785 | */ | |
786 | if (cgrp1 != cgrp2) | |
787 | perf_cgroup_switch(task, PERF_CGROUP_SWIN); | |
ddaaf4e2 SE |
788 | |
789 | rcu_read_unlock(); | |
e5d1367f SE |
790 | } |
791 | ||
792 | static inline int perf_cgroup_connect(int fd, struct perf_event *event, | |
793 | struct perf_event_attr *attr, | |
794 | struct perf_event *group_leader) | |
795 | { | |
796 | struct perf_cgroup *cgrp; | |
797 | struct cgroup_subsys_state *css; | |
2903ff01 AV |
798 | struct fd f = fdget(fd); |
799 | int ret = 0; | |
e5d1367f | 800 | |
2903ff01 | 801 | if (!f.file) |
e5d1367f SE |
802 | return -EBADF; |
803 | ||
b583043e | 804 | css = css_tryget_online_from_dir(f.file->f_path.dentry, |
ec903c0c | 805 | &perf_event_cgrp_subsys); |
3db272c0 LZ |
806 | if (IS_ERR(css)) { |
807 | ret = PTR_ERR(css); | |
808 | goto out; | |
809 | } | |
e5d1367f SE |
810 | |
811 | cgrp = container_of(css, struct perf_cgroup, css); | |
812 | event->cgrp = cgrp; | |
813 | ||
814 | /* | |
815 | * all events in a group must monitor | |
816 | * the same cgroup because a task belongs | |
817 | * to only one perf cgroup at a time | |
818 | */ | |
819 | if (group_leader && group_leader->cgrp != cgrp) { | |
820 | perf_detach_cgroup(event); | |
821 | ret = -EINVAL; | |
e5d1367f | 822 | } |
3db272c0 | 823 | out: |
2903ff01 | 824 | fdput(f); |
e5d1367f SE |
825 | return ret; |
826 | } | |
827 | ||
828 | static inline void | |
829 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
830 | { | |
831 | struct perf_cgroup_info *t; | |
832 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
833 | event->shadow_ctx_time = now - t->timestamp; | |
834 | } | |
835 | ||
836 | static inline void | |
837 | perf_cgroup_defer_enabled(struct perf_event *event) | |
838 | { | |
839 | /* | |
840 | * when the current task's perf cgroup does not match | |
841 | * the event's, we need to remember to call the | |
842 | * perf_mark_enable() function the first time a task with | |
843 | * a matching perf cgroup is scheduled in. | |
844 | */ | |
845 | if (is_cgroup_event(event) && !perf_cgroup_match(event)) | |
846 | event->cgrp_defer_enabled = 1; | |
847 | } | |
848 | ||
849 | static inline void | |
850 | perf_cgroup_mark_enabled(struct perf_event *event, | |
851 | struct perf_event_context *ctx) | |
852 | { | |
853 | struct perf_event *sub; | |
854 | u64 tstamp = perf_event_time(event); | |
855 | ||
856 | if (!event->cgrp_defer_enabled) | |
857 | return; | |
858 | ||
859 | event->cgrp_defer_enabled = 0; | |
860 | ||
861 | event->tstamp_enabled = tstamp - event->total_time_enabled; | |
862 | list_for_each_entry(sub, &event->sibling_list, group_entry) { | |
863 | if (sub->state >= PERF_EVENT_STATE_INACTIVE) { | |
864 | sub->tstamp_enabled = tstamp - sub->total_time_enabled; | |
865 | sub->cgrp_defer_enabled = 0; | |
866 | } | |
867 | } | |
868 | } | |
db4a8356 DCC |
869 | |
870 | /* | |
871 | * Update cpuctx->cgrp so that it is set when first cgroup event is added and | |
872 | * cleared when last cgroup event is removed. | |
873 | */ | |
874 | static inline void | |
875 | list_update_cgroup_event(struct perf_event *event, | |
876 | struct perf_event_context *ctx, bool add) | |
877 | { | |
878 | struct perf_cpu_context *cpuctx; | |
058fe1c0 | 879 | struct list_head *cpuctx_entry; |
db4a8356 DCC |
880 | |
881 | if (!is_cgroup_event(event)) | |
882 | return; | |
883 | ||
884 | if (add && ctx->nr_cgroups++) | |
885 | return; | |
886 | else if (!add && --ctx->nr_cgroups) | |
887 | return; | |
888 | /* | |
889 | * Because cgroup events are always per-cpu events, | |
890 | * this will always be called from the right CPU. | |
891 | */ | |
892 | cpuctx = __get_cpu_context(ctx); | |
058fe1c0 DCC |
893 | cpuctx_entry = &cpuctx->cgrp_cpuctx_entry; |
894 | /* cpuctx->cgrp is NULL unless a cgroup event is active in this CPU .*/ | |
895 | if (add) { | |
896 | list_add(cpuctx_entry, this_cpu_ptr(&cgrp_cpuctx_list)); | |
897 | if (perf_cgroup_from_task(current, ctx) == event->cgrp) | |
898 | cpuctx->cgrp = event->cgrp; | |
899 | } else { | |
900 | list_del(cpuctx_entry); | |
8fc31ce8 | 901 | cpuctx->cgrp = NULL; |
058fe1c0 | 902 | } |
db4a8356 DCC |
903 | } |
904 | ||
e5d1367f SE |
905 | #else /* !CONFIG_CGROUP_PERF */ |
906 | ||
907 | static inline bool | |
908 | perf_cgroup_match(struct perf_event *event) | |
909 | { | |
910 | return true; | |
911 | } | |
912 | ||
913 | static inline void perf_detach_cgroup(struct perf_event *event) | |
914 | {} | |
915 | ||
916 | static inline int is_cgroup_event(struct perf_event *event) | |
917 | { | |
918 | return 0; | |
919 | } | |
920 | ||
921 | static inline u64 perf_cgroup_event_cgrp_time(struct perf_event *event) | |
922 | { | |
923 | return 0; | |
924 | } | |
925 | ||
926 | static inline void update_cgrp_time_from_event(struct perf_event *event) | |
927 | { | |
928 | } | |
929 | ||
930 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
931 | { | |
932 | } | |
933 | ||
a8d757ef SE |
934 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
935 | struct task_struct *next) | |
e5d1367f SE |
936 | { |
937 | } | |
938 | ||
a8d757ef SE |
939 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
940 | struct task_struct *task) | |
e5d1367f SE |
941 | { |
942 | } | |
943 | ||
944 | static inline int perf_cgroup_connect(pid_t pid, struct perf_event *event, | |
945 | struct perf_event_attr *attr, | |
946 | struct perf_event *group_leader) | |
947 | { | |
948 | return -EINVAL; | |
949 | } | |
950 | ||
951 | static inline void | |
3f7cce3c SE |
952 | perf_cgroup_set_timestamp(struct task_struct *task, |
953 | struct perf_event_context *ctx) | |
e5d1367f SE |
954 | { |
955 | } | |
956 | ||
957 | void | |
958 | perf_cgroup_switch(struct task_struct *task, struct task_struct *next) | |
959 | { | |
960 | } | |
961 | ||
962 | static inline void | |
963 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
964 | { | |
965 | } | |
966 | ||
967 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
968 | { | |
969 | return 0; | |
970 | } | |
971 | ||
972 | static inline void | |
973 | perf_cgroup_defer_enabled(struct perf_event *event) | |
974 | { | |
975 | } | |
976 | ||
977 | static inline void | |
978 | perf_cgroup_mark_enabled(struct perf_event *event, | |
979 | struct perf_event_context *ctx) | |
980 | { | |
981 | } | |
db4a8356 DCC |
982 | |
983 | static inline void | |
984 | list_update_cgroup_event(struct perf_event *event, | |
985 | struct perf_event_context *ctx, bool add) | |
986 | { | |
987 | } | |
988 | ||
e5d1367f SE |
989 | #endif |
990 | ||
9e630205 SE |
991 | /* |
992 | * set default to be dependent on timer tick just | |
993 | * like original code | |
994 | */ | |
995 | #define PERF_CPU_HRTIMER (1000 / HZ) | |
996 | /* | |
997 | * function must be called with interrupts disbled | |
998 | */ | |
272325c4 | 999 | static enum hrtimer_restart perf_mux_hrtimer_handler(struct hrtimer *hr) |
9e630205 SE |
1000 | { |
1001 | struct perf_cpu_context *cpuctx; | |
9e630205 SE |
1002 | int rotations = 0; |
1003 | ||
1004 | WARN_ON(!irqs_disabled()); | |
1005 | ||
1006 | cpuctx = container_of(hr, struct perf_cpu_context, hrtimer); | |
9e630205 SE |
1007 | rotations = perf_rotate_context(cpuctx); |
1008 | ||
4cfafd30 PZ |
1009 | raw_spin_lock(&cpuctx->hrtimer_lock); |
1010 | if (rotations) | |
9e630205 | 1011 | hrtimer_forward_now(hr, cpuctx->hrtimer_interval); |
4cfafd30 PZ |
1012 | else |
1013 | cpuctx->hrtimer_active = 0; | |
1014 | raw_spin_unlock(&cpuctx->hrtimer_lock); | |
9e630205 | 1015 | |
4cfafd30 | 1016 | return rotations ? HRTIMER_RESTART : HRTIMER_NORESTART; |
9e630205 SE |
1017 | } |
1018 | ||
272325c4 | 1019 | static void __perf_mux_hrtimer_init(struct perf_cpu_context *cpuctx, int cpu) |
9e630205 | 1020 | { |
272325c4 | 1021 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1022 | struct pmu *pmu = cpuctx->ctx.pmu; |
272325c4 | 1023 | u64 interval; |
9e630205 SE |
1024 | |
1025 | /* no multiplexing needed for SW PMU */ | |
1026 | if (pmu->task_ctx_nr == perf_sw_context) | |
1027 | return; | |
1028 | ||
62b85639 SE |
1029 | /* |
1030 | * check default is sane, if not set then force to | |
1031 | * default interval (1/tick) | |
1032 | */ | |
272325c4 PZ |
1033 | interval = pmu->hrtimer_interval_ms; |
1034 | if (interval < 1) | |
1035 | interval = pmu->hrtimer_interval_ms = PERF_CPU_HRTIMER; | |
62b85639 | 1036 | |
272325c4 | 1037 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * interval); |
9e630205 | 1038 | |
4cfafd30 PZ |
1039 | raw_spin_lock_init(&cpuctx->hrtimer_lock); |
1040 | hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_PINNED); | |
272325c4 | 1041 | timer->function = perf_mux_hrtimer_handler; |
9e630205 SE |
1042 | } |
1043 | ||
272325c4 | 1044 | static int perf_mux_hrtimer_restart(struct perf_cpu_context *cpuctx) |
9e630205 | 1045 | { |
272325c4 | 1046 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1047 | struct pmu *pmu = cpuctx->ctx.pmu; |
4cfafd30 | 1048 | unsigned long flags; |
9e630205 SE |
1049 | |
1050 | /* not for SW PMU */ | |
1051 | if (pmu->task_ctx_nr == perf_sw_context) | |
272325c4 | 1052 | return 0; |
9e630205 | 1053 | |
4cfafd30 PZ |
1054 | raw_spin_lock_irqsave(&cpuctx->hrtimer_lock, flags); |
1055 | if (!cpuctx->hrtimer_active) { | |
1056 | cpuctx->hrtimer_active = 1; | |
1057 | hrtimer_forward_now(timer, cpuctx->hrtimer_interval); | |
1058 | hrtimer_start_expires(timer, HRTIMER_MODE_ABS_PINNED); | |
1059 | } | |
1060 | raw_spin_unlock_irqrestore(&cpuctx->hrtimer_lock, flags); | |
9e630205 | 1061 | |
272325c4 | 1062 | return 0; |
9e630205 SE |
1063 | } |
1064 | ||
33696fc0 | 1065 | void perf_pmu_disable(struct pmu *pmu) |
9e35ad38 | 1066 | { |
33696fc0 PZ |
1067 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1068 | if (!(*count)++) | |
1069 | pmu->pmu_disable(pmu); | |
9e35ad38 | 1070 | } |
9e35ad38 | 1071 | |
33696fc0 | 1072 | void perf_pmu_enable(struct pmu *pmu) |
9e35ad38 | 1073 | { |
33696fc0 PZ |
1074 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1075 | if (!--(*count)) | |
1076 | pmu->pmu_enable(pmu); | |
9e35ad38 | 1077 | } |
9e35ad38 | 1078 | |
2fde4f94 | 1079 | static DEFINE_PER_CPU(struct list_head, active_ctx_list); |
e9d2b064 PZ |
1080 | |
1081 | /* | |
2fde4f94 MR |
1082 | * perf_event_ctx_activate(), perf_event_ctx_deactivate(), and |
1083 | * perf_event_task_tick() are fully serialized because they're strictly cpu | |
1084 | * affine and perf_event_ctx{activate,deactivate} are called with IRQs | |
1085 | * disabled, while perf_event_task_tick is called from IRQ context. | |
e9d2b064 | 1086 | */ |
2fde4f94 | 1087 | static void perf_event_ctx_activate(struct perf_event_context *ctx) |
9e35ad38 | 1088 | { |
2fde4f94 | 1089 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
b5ab4cd5 | 1090 | |
e9d2b064 | 1091 | WARN_ON(!irqs_disabled()); |
b5ab4cd5 | 1092 | |
2fde4f94 MR |
1093 | WARN_ON(!list_empty(&ctx->active_ctx_list)); |
1094 | ||
1095 | list_add(&ctx->active_ctx_list, head); | |
1096 | } | |
1097 | ||
1098 | static void perf_event_ctx_deactivate(struct perf_event_context *ctx) | |
1099 | { | |
1100 | WARN_ON(!irqs_disabled()); | |
1101 | ||
1102 | WARN_ON(list_empty(&ctx->active_ctx_list)); | |
1103 | ||
1104 | list_del_init(&ctx->active_ctx_list); | |
9e35ad38 | 1105 | } |
9e35ad38 | 1106 | |
cdd6c482 | 1107 | static void get_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1108 | { |
e5289d4a | 1109 | WARN_ON(!atomic_inc_not_zero(&ctx->refcount)); |
a63eaf34 PM |
1110 | } |
1111 | ||
4af57ef2 YZ |
1112 | static void free_ctx(struct rcu_head *head) |
1113 | { | |
1114 | struct perf_event_context *ctx; | |
1115 | ||
1116 | ctx = container_of(head, struct perf_event_context, rcu_head); | |
1117 | kfree(ctx->task_ctx_data); | |
1118 | kfree(ctx); | |
1119 | } | |
1120 | ||
cdd6c482 | 1121 | static void put_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1122 | { |
564c2b21 PM |
1123 | if (atomic_dec_and_test(&ctx->refcount)) { |
1124 | if (ctx->parent_ctx) | |
1125 | put_ctx(ctx->parent_ctx); | |
63b6da39 | 1126 | if (ctx->task && ctx->task != TASK_TOMBSTONE) |
c93f7669 | 1127 | put_task_struct(ctx->task); |
4af57ef2 | 1128 | call_rcu(&ctx->rcu_head, free_ctx); |
564c2b21 | 1129 | } |
a63eaf34 PM |
1130 | } |
1131 | ||
f63a8daa PZ |
1132 | /* |
1133 | * Because of perf_event::ctx migration in sys_perf_event_open::move_group and | |
1134 | * perf_pmu_migrate_context() we need some magic. | |
1135 | * | |
1136 | * Those places that change perf_event::ctx will hold both | |
1137 | * perf_event_ctx::mutex of the 'old' and 'new' ctx value. | |
1138 | * | |
8b10c5e2 PZ |
1139 | * Lock ordering is by mutex address. There are two other sites where |
1140 | * perf_event_context::mutex nests and those are: | |
1141 | * | |
1142 | * - perf_event_exit_task_context() [ child , 0 ] | |
8ba289b8 PZ |
1143 | * perf_event_exit_event() |
1144 | * put_event() [ parent, 1 ] | |
8b10c5e2 PZ |
1145 | * |
1146 | * - perf_event_init_context() [ parent, 0 ] | |
1147 | * inherit_task_group() | |
1148 | * inherit_group() | |
1149 | * inherit_event() | |
1150 | * perf_event_alloc() | |
1151 | * perf_init_event() | |
1152 | * perf_try_init_event() [ child , 1 ] | |
1153 | * | |
1154 | * While it appears there is an obvious deadlock here -- the parent and child | |
1155 | * nesting levels are inverted between the two. This is in fact safe because | |
1156 | * life-time rules separate them. That is an exiting task cannot fork, and a | |
1157 | * spawning task cannot (yet) exit. | |
1158 | * | |
1159 | * But remember that that these are parent<->child context relations, and | |
1160 | * migration does not affect children, therefore these two orderings should not | |
1161 | * interact. | |
f63a8daa PZ |
1162 | * |
1163 | * The change in perf_event::ctx does not affect children (as claimed above) | |
1164 | * because the sys_perf_event_open() case will install a new event and break | |
1165 | * the ctx parent<->child relation, and perf_pmu_migrate_context() is only | |
1166 | * concerned with cpuctx and that doesn't have children. | |
1167 | * | |
1168 | * The places that change perf_event::ctx will issue: | |
1169 | * | |
1170 | * perf_remove_from_context(); | |
1171 | * synchronize_rcu(); | |
1172 | * perf_install_in_context(); | |
1173 | * | |
1174 | * to affect the change. The remove_from_context() + synchronize_rcu() should | |
1175 | * quiesce the event, after which we can install it in the new location. This | |
1176 | * means that only external vectors (perf_fops, prctl) can perturb the event | |
1177 | * while in transit. Therefore all such accessors should also acquire | |
1178 | * perf_event_context::mutex to serialize against this. | |
1179 | * | |
1180 | * However; because event->ctx can change while we're waiting to acquire | |
1181 | * ctx->mutex we must be careful and use the below perf_event_ctx_lock() | |
1182 | * function. | |
1183 | * | |
1184 | * Lock order: | |
79c9ce57 | 1185 | * cred_guard_mutex |
f63a8daa PZ |
1186 | * task_struct::perf_event_mutex |
1187 | * perf_event_context::mutex | |
f63a8daa | 1188 | * perf_event::child_mutex; |
07c4a776 | 1189 | * perf_event_context::lock |
f63a8daa PZ |
1190 | * perf_event::mmap_mutex |
1191 | * mmap_sem | |
1192 | */ | |
a83fe28e PZ |
1193 | static struct perf_event_context * |
1194 | perf_event_ctx_lock_nested(struct perf_event *event, int nesting) | |
f63a8daa PZ |
1195 | { |
1196 | struct perf_event_context *ctx; | |
1197 | ||
1198 | again: | |
1199 | rcu_read_lock(); | |
1200 | ctx = ACCESS_ONCE(event->ctx); | |
1201 | if (!atomic_inc_not_zero(&ctx->refcount)) { | |
1202 | rcu_read_unlock(); | |
1203 | goto again; | |
1204 | } | |
1205 | rcu_read_unlock(); | |
1206 | ||
a83fe28e | 1207 | mutex_lock_nested(&ctx->mutex, nesting); |
f63a8daa PZ |
1208 | if (event->ctx != ctx) { |
1209 | mutex_unlock(&ctx->mutex); | |
1210 | put_ctx(ctx); | |
1211 | goto again; | |
1212 | } | |
1213 | ||
1214 | return ctx; | |
1215 | } | |
1216 | ||
a83fe28e PZ |
1217 | static inline struct perf_event_context * |
1218 | perf_event_ctx_lock(struct perf_event *event) | |
1219 | { | |
1220 | return perf_event_ctx_lock_nested(event, 0); | |
1221 | } | |
1222 | ||
f63a8daa PZ |
1223 | static void perf_event_ctx_unlock(struct perf_event *event, |
1224 | struct perf_event_context *ctx) | |
1225 | { | |
1226 | mutex_unlock(&ctx->mutex); | |
1227 | put_ctx(ctx); | |
1228 | } | |
1229 | ||
211de6eb PZ |
1230 | /* |
1231 | * This must be done under the ctx->lock, such as to serialize against | |
1232 | * context_equiv(), therefore we cannot call put_ctx() since that might end up | |
1233 | * calling scheduler related locks and ctx->lock nests inside those. | |
1234 | */ | |
1235 | static __must_check struct perf_event_context * | |
1236 | unclone_ctx(struct perf_event_context *ctx) | |
71a851b4 | 1237 | { |
211de6eb PZ |
1238 | struct perf_event_context *parent_ctx = ctx->parent_ctx; |
1239 | ||
1240 | lockdep_assert_held(&ctx->lock); | |
1241 | ||
1242 | if (parent_ctx) | |
71a851b4 | 1243 | ctx->parent_ctx = NULL; |
5a3126d4 | 1244 | ctx->generation++; |
211de6eb PZ |
1245 | |
1246 | return parent_ctx; | |
71a851b4 PZ |
1247 | } |
1248 | ||
6844c09d ACM |
1249 | static u32 perf_event_pid(struct perf_event *event, struct task_struct *p) |
1250 | { | |
1251 | /* | |
1252 | * only top level events have the pid namespace they were created in | |
1253 | */ | |
1254 | if (event->parent) | |
1255 | event = event->parent; | |
1256 | ||
1257 | return task_tgid_nr_ns(p, event->ns); | |
1258 | } | |
1259 | ||
1260 | static u32 perf_event_tid(struct perf_event *event, struct task_struct *p) | |
1261 | { | |
1262 | /* | |
1263 | * only top level events have the pid namespace they were created in | |
1264 | */ | |
1265 | if (event->parent) | |
1266 | event = event->parent; | |
1267 | ||
1268 | return task_pid_nr_ns(p, event->ns); | |
1269 | } | |
1270 | ||
7f453c24 | 1271 | /* |
cdd6c482 | 1272 | * If we inherit events we want to return the parent event id |
7f453c24 PZ |
1273 | * to userspace. |
1274 | */ | |
cdd6c482 | 1275 | static u64 primary_event_id(struct perf_event *event) |
7f453c24 | 1276 | { |
cdd6c482 | 1277 | u64 id = event->id; |
7f453c24 | 1278 | |
cdd6c482 IM |
1279 | if (event->parent) |
1280 | id = event->parent->id; | |
7f453c24 PZ |
1281 | |
1282 | return id; | |
1283 | } | |
1284 | ||
25346b93 | 1285 | /* |
cdd6c482 | 1286 | * Get the perf_event_context for a task and lock it. |
63b6da39 | 1287 | * |
25346b93 PM |
1288 | * This has to cope with with the fact that until it is locked, |
1289 | * the context could get moved to another task. | |
1290 | */ | |
cdd6c482 | 1291 | static struct perf_event_context * |
8dc85d54 | 1292 | perf_lock_task_context(struct task_struct *task, int ctxn, unsigned long *flags) |
25346b93 | 1293 | { |
cdd6c482 | 1294 | struct perf_event_context *ctx; |
25346b93 | 1295 | |
9ed6060d | 1296 | retry: |
058ebd0e PZ |
1297 | /* |
1298 | * One of the few rules of preemptible RCU is that one cannot do | |
1299 | * rcu_read_unlock() while holding a scheduler (or nested) lock when | |
2fd59077 | 1300 | * part of the read side critical section was irqs-enabled -- see |
058ebd0e PZ |
1301 | * rcu_read_unlock_special(). |
1302 | * | |
1303 | * Since ctx->lock nests under rq->lock we must ensure the entire read | |
2fd59077 | 1304 | * side critical section has interrupts disabled. |
058ebd0e | 1305 | */ |
2fd59077 | 1306 | local_irq_save(*flags); |
058ebd0e | 1307 | rcu_read_lock(); |
8dc85d54 | 1308 | ctx = rcu_dereference(task->perf_event_ctxp[ctxn]); |
25346b93 PM |
1309 | if (ctx) { |
1310 | /* | |
1311 | * If this context is a clone of another, it might | |
1312 | * get swapped for another underneath us by | |
cdd6c482 | 1313 | * perf_event_task_sched_out, though the |
25346b93 PM |
1314 | * rcu_read_lock() protects us from any context |
1315 | * getting freed. Lock the context and check if it | |
1316 | * got swapped before we could get the lock, and retry | |
1317 | * if so. If we locked the right context, then it | |
1318 | * can't get swapped on us any more. | |
1319 | */ | |
2fd59077 | 1320 | raw_spin_lock(&ctx->lock); |
8dc85d54 | 1321 | if (ctx != rcu_dereference(task->perf_event_ctxp[ctxn])) { |
2fd59077 | 1322 | raw_spin_unlock(&ctx->lock); |
058ebd0e | 1323 | rcu_read_unlock(); |
2fd59077 | 1324 | local_irq_restore(*flags); |
25346b93 PM |
1325 | goto retry; |
1326 | } | |
b49a9e7e | 1327 | |
63b6da39 PZ |
1328 | if (ctx->task == TASK_TOMBSTONE || |
1329 | !atomic_inc_not_zero(&ctx->refcount)) { | |
2fd59077 | 1330 | raw_spin_unlock(&ctx->lock); |
b49a9e7e | 1331 | ctx = NULL; |
828b6f0e PZ |
1332 | } else { |
1333 | WARN_ON_ONCE(ctx->task != task); | |
b49a9e7e | 1334 | } |
25346b93 PM |
1335 | } |
1336 | rcu_read_unlock(); | |
2fd59077 PM |
1337 | if (!ctx) |
1338 | local_irq_restore(*flags); | |
25346b93 PM |
1339 | return ctx; |
1340 | } | |
1341 | ||
1342 | /* | |
1343 | * Get the context for a task and increment its pin_count so it | |
1344 | * can't get swapped to another task. This also increments its | |
1345 | * reference count so that the context can't get freed. | |
1346 | */ | |
8dc85d54 PZ |
1347 | static struct perf_event_context * |
1348 | perf_pin_task_context(struct task_struct *task, int ctxn) | |
25346b93 | 1349 | { |
cdd6c482 | 1350 | struct perf_event_context *ctx; |
25346b93 PM |
1351 | unsigned long flags; |
1352 | ||
8dc85d54 | 1353 | ctx = perf_lock_task_context(task, ctxn, &flags); |
25346b93 PM |
1354 | if (ctx) { |
1355 | ++ctx->pin_count; | |
e625cce1 | 1356 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1357 | } |
1358 | return ctx; | |
1359 | } | |
1360 | ||
cdd6c482 | 1361 | static void perf_unpin_context(struct perf_event_context *ctx) |
25346b93 PM |
1362 | { |
1363 | unsigned long flags; | |
1364 | ||
e625cce1 | 1365 | raw_spin_lock_irqsave(&ctx->lock, flags); |
25346b93 | 1366 | --ctx->pin_count; |
e625cce1 | 1367 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1368 | } |
1369 | ||
f67218c3 PZ |
1370 | /* |
1371 | * Update the record of the current time in a context. | |
1372 | */ | |
1373 | static void update_context_time(struct perf_event_context *ctx) | |
1374 | { | |
1375 | u64 now = perf_clock(); | |
1376 | ||
1377 | ctx->time += now - ctx->timestamp; | |
1378 | ctx->timestamp = now; | |
1379 | } | |
1380 | ||
4158755d SE |
1381 | static u64 perf_event_time(struct perf_event *event) |
1382 | { | |
1383 | struct perf_event_context *ctx = event->ctx; | |
e5d1367f SE |
1384 | |
1385 | if (is_cgroup_event(event)) | |
1386 | return perf_cgroup_event_time(event); | |
1387 | ||
4158755d SE |
1388 | return ctx ? ctx->time : 0; |
1389 | } | |
1390 | ||
f67218c3 PZ |
1391 | /* |
1392 | * Update the total_time_enabled and total_time_running fields for a event. | |
1393 | */ | |
1394 | static void update_event_times(struct perf_event *event) | |
1395 | { | |
1396 | struct perf_event_context *ctx = event->ctx; | |
1397 | u64 run_end; | |
1398 | ||
3cbaa590 PZ |
1399 | lockdep_assert_held(&ctx->lock); |
1400 | ||
f67218c3 PZ |
1401 | if (event->state < PERF_EVENT_STATE_INACTIVE || |
1402 | event->group_leader->state < PERF_EVENT_STATE_INACTIVE) | |
1403 | return; | |
3cbaa590 | 1404 | |
e5d1367f SE |
1405 | /* |
1406 | * in cgroup mode, time_enabled represents | |
1407 | * the time the event was enabled AND active | |
1408 | * tasks were in the monitored cgroup. This is | |
1409 | * independent of the activity of the context as | |
1410 | * there may be a mix of cgroup and non-cgroup events. | |
1411 | * | |
1412 | * That is why we treat cgroup events differently | |
1413 | * here. | |
1414 | */ | |
1415 | if (is_cgroup_event(event)) | |
46cd6a7f | 1416 | run_end = perf_cgroup_event_time(event); |
e5d1367f SE |
1417 | else if (ctx->is_active) |
1418 | run_end = ctx->time; | |
acd1d7c1 PZ |
1419 | else |
1420 | run_end = event->tstamp_stopped; | |
1421 | ||
1422 | event->total_time_enabled = run_end - event->tstamp_enabled; | |
f67218c3 PZ |
1423 | |
1424 | if (event->state == PERF_EVENT_STATE_INACTIVE) | |
1425 | run_end = event->tstamp_stopped; | |
1426 | else | |
4158755d | 1427 | run_end = perf_event_time(event); |
f67218c3 PZ |
1428 | |
1429 | event->total_time_running = run_end - event->tstamp_running; | |
e5d1367f | 1430 | |
f67218c3 PZ |
1431 | } |
1432 | ||
96c21a46 PZ |
1433 | /* |
1434 | * Update total_time_enabled and total_time_running for all events in a group. | |
1435 | */ | |
1436 | static void update_group_times(struct perf_event *leader) | |
1437 | { | |
1438 | struct perf_event *event; | |
1439 | ||
1440 | update_event_times(leader); | |
1441 | list_for_each_entry(event, &leader->sibling_list, group_entry) | |
1442 | update_event_times(event); | |
1443 | } | |
1444 | ||
889ff015 FW |
1445 | static struct list_head * |
1446 | ctx_group_list(struct perf_event *event, struct perf_event_context *ctx) | |
1447 | { | |
1448 | if (event->attr.pinned) | |
1449 | return &ctx->pinned_groups; | |
1450 | else | |
1451 | return &ctx->flexible_groups; | |
1452 | } | |
1453 | ||
fccc714b | 1454 | /* |
cdd6c482 | 1455 | * Add a event from the lists for its context. |
fccc714b PZ |
1456 | * Must be called with ctx->mutex and ctx->lock held. |
1457 | */ | |
04289bb9 | 1458 | static void |
cdd6c482 | 1459 | list_add_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1460 | { |
c994d613 PZ |
1461 | lockdep_assert_held(&ctx->lock); |
1462 | ||
8a49542c PZ |
1463 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); |
1464 | event->attach_state |= PERF_ATTACH_CONTEXT; | |
04289bb9 IM |
1465 | |
1466 | /* | |
8a49542c PZ |
1467 | * If we're a stand alone event or group leader, we go to the context |
1468 | * list, group events are kept attached to the group so that | |
1469 | * perf_group_detach can, at all times, locate all siblings. | |
04289bb9 | 1470 | */ |
8a49542c | 1471 | if (event->group_leader == event) { |
889ff015 FW |
1472 | struct list_head *list; |
1473 | ||
4ff6a8de | 1474 | event->group_caps = event->event_caps; |
d6f962b5 | 1475 | |
889ff015 FW |
1476 | list = ctx_group_list(event, ctx); |
1477 | list_add_tail(&event->group_entry, list); | |
5c148194 | 1478 | } |
592903cd | 1479 | |
db4a8356 | 1480 | list_update_cgroup_event(event, ctx, true); |
e5d1367f | 1481 | |
cdd6c482 IM |
1482 | list_add_rcu(&event->event_entry, &ctx->event_list); |
1483 | ctx->nr_events++; | |
1484 | if (event->attr.inherit_stat) | |
bfbd3381 | 1485 | ctx->nr_stat++; |
5a3126d4 PZ |
1486 | |
1487 | ctx->generation++; | |
04289bb9 IM |
1488 | } |
1489 | ||
0231bb53 JO |
1490 | /* |
1491 | * Initialize event state based on the perf_event_attr::disabled. | |
1492 | */ | |
1493 | static inline void perf_event__state_init(struct perf_event *event) | |
1494 | { | |
1495 | event->state = event->attr.disabled ? PERF_EVENT_STATE_OFF : | |
1496 | PERF_EVENT_STATE_INACTIVE; | |
1497 | } | |
1498 | ||
a723968c | 1499 | static void __perf_event_read_size(struct perf_event *event, int nr_siblings) |
c320c7b7 ACM |
1500 | { |
1501 | int entry = sizeof(u64); /* value */ | |
1502 | int size = 0; | |
1503 | int nr = 1; | |
1504 | ||
1505 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
1506 | size += sizeof(u64); | |
1507 | ||
1508 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
1509 | size += sizeof(u64); | |
1510 | ||
1511 | if (event->attr.read_format & PERF_FORMAT_ID) | |
1512 | entry += sizeof(u64); | |
1513 | ||
1514 | if (event->attr.read_format & PERF_FORMAT_GROUP) { | |
a723968c | 1515 | nr += nr_siblings; |
c320c7b7 ACM |
1516 | size += sizeof(u64); |
1517 | } | |
1518 | ||
1519 | size += entry * nr; | |
1520 | event->read_size = size; | |
1521 | } | |
1522 | ||
a723968c | 1523 | static void __perf_event_header_size(struct perf_event *event, u64 sample_type) |
c320c7b7 ACM |
1524 | { |
1525 | struct perf_sample_data *data; | |
c320c7b7 ACM |
1526 | u16 size = 0; |
1527 | ||
c320c7b7 ACM |
1528 | if (sample_type & PERF_SAMPLE_IP) |
1529 | size += sizeof(data->ip); | |
1530 | ||
6844c09d ACM |
1531 | if (sample_type & PERF_SAMPLE_ADDR) |
1532 | size += sizeof(data->addr); | |
1533 | ||
1534 | if (sample_type & PERF_SAMPLE_PERIOD) | |
1535 | size += sizeof(data->period); | |
1536 | ||
c3feedf2 AK |
1537 | if (sample_type & PERF_SAMPLE_WEIGHT) |
1538 | size += sizeof(data->weight); | |
1539 | ||
6844c09d ACM |
1540 | if (sample_type & PERF_SAMPLE_READ) |
1541 | size += event->read_size; | |
1542 | ||
d6be9ad6 SE |
1543 | if (sample_type & PERF_SAMPLE_DATA_SRC) |
1544 | size += sizeof(data->data_src.val); | |
1545 | ||
fdfbbd07 AK |
1546 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
1547 | size += sizeof(data->txn); | |
1548 | ||
6844c09d ACM |
1549 | event->header_size = size; |
1550 | } | |
1551 | ||
a723968c PZ |
1552 | /* |
1553 | * Called at perf_event creation and when events are attached/detached from a | |
1554 | * group. | |
1555 | */ | |
1556 | static void perf_event__header_size(struct perf_event *event) | |
1557 | { | |
1558 | __perf_event_read_size(event, | |
1559 | event->group_leader->nr_siblings); | |
1560 | __perf_event_header_size(event, event->attr.sample_type); | |
1561 | } | |
1562 | ||
6844c09d ACM |
1563 | static void perf_event__id_header_size(struct perf_event *event) |
1564 | { | |
1565 | struct perf_sample_data *data; | |
1566 | u64 sample_type = event->attr.sample_type; | |
1567 | u16 size = 0; | |
1568 | ||
c320c7b7 ACM |
1569 | if (sample_type & PERF_SAMPLE_TID) |
1570 | size += sizeof(data->tid_entry); | |
1571 | ||
1572 | if (sample_type & PERF_SAMPLE_TIME) | |
1573 | size += sizeof(data->time); | |
1574 | ||
ff3d527c AH |
1575 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
1576 | size += sizeof(data->id); | |
1577 | ||
c320c7b7 ACM |
1578 | if (sample_type & PERF_SAMPLE_ID) |
1579 | size += sizeof(data->id); | |
1580 | ||
1581 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
1582 | size += sizeof(data->stream_id); | |
1583 | ||
1584 | if (sample_type & PERF_SAMPLE_CPU) | |
1585 | size += sizeof(data->cpu_entry); | |
1586 | ||
6844c09d | 1587 | event->id_header_size = size; |
c320c7b7 ACM |
1588 | } |
1589 | ||
a723968c PZ |
1590 | static bool perf_event_validate_size(struct perf_event *event) |
1591 | { | |
1592 | /* | |
1593 | * The values computed here will be over-written when we actually | |
1594 | * attach the event. | |
1595 | */ | |
1596 | __perf_event_read_size(event, event->group_leader->nr_siblings + 1); | |
1597 | __perf_event_header_size(event, event->attr.sample_type & ~PERF_SAMPLE_READ); | |
1598 | perf_event__id_header_size(event); | |
1599 | ||
1600 | /* | |
1601 | * Sum the lot; should not exceed the 64k limit we have on records. | |
1602 | * Conservative limit to allow for callchains and other variable fields. | |
1603 | */ | |
1604 | if (event->read_size + event->header_size + | |
1605 | event->id_header_size + sizeof(struct perf_event_header) >= 16*1024) | |
1606 | return false; | |
1607 | ||
1608 | return true; | |
1609 | } | |
1610 | ||
8a49542c PZ |
1611 | static void perf_group_attach(struct perf_event *event) |
1612 | { | |
c320c7b7 | 1613 | struct perf_event *group_leader = event->group_leader, *pos; |
8a49542c | 1614 | |
a76a82a3 PZ |
1615 | lockdep_assert_held(&event->ctx->lock); |
1616 | ||
74c3337c PZ |
1617 | /* |
1618 | * We can have double attach due to group movement in perf_event_open. | |
1619 | */ | |
1620 | if (event->attach_state & PERF_ATTACH_GROUP) | |
1621 | return; | |
1622 | ||
8a49542c PZ |
1623 | event->attach_state |= PERF_ATTACH_GROUP; |
1624 | ||
1625 | if (group_leader == event) | |
1626 | return; | |
1627 | ||
652884fe PZ |
1628 | WARN_ON_ONCE(group_leader->ctx != event->ctx); |
1629 | ||
4ff6a8de | 1630 | group_leader->group_caps &= event->event_caps; |
8a49542c PZ |
1631 | |
1632 | list_add_tail(&event->group_entry, &group_leader->sibling_list); | |
1633 | group_leader->nr_siblings++; | |
c320c7b7 ACM |
1634 | |
1635 | perf_event__header_size(group_leader); | |
1636 | ||
1637 | list_for_each_entry(pos, &group_leader->sibling_list, group_entry) | |
1638 | perf_event__header_size(pos); | |
8a49542c PZ |
1639 | } |
1640 | ||
a63eaf34 | 1641 | /* |
cdd6c482 | 1642 | * Remove a event from the lists for its context. |
fccc714b | 1643 | * Must be called with ctx->mutex and ctx->lock held. |
a63eaf34 | 1644 | */ |
04289bb9 | 1645 | static void |
cdd6c482 | 1646 | list_del_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1647 | { |
652884fe PZ |
1648 | WARN_ON_ONCE(event->ctx != ctx); |
1649 | lockdep_assert_held(&ctx->lock); | |
1650 | ||
8a49542c PZ |
1651 | /* |
1652 | * We can have double detach due to exit/hot-unplug + close. | |
1653 | */ | |
1654 | if (!(event->attach_state & PERF_ATTACH_CONTEXT)) | |
a63eaf34 | 1655 | return; |
8a49542c PZ |
1656 | |
1657 | event->attach_state &= ~PERF_ATTACH_CONTEXT; | |
1658 | ||
db4a8356 | 1659 | list_update_cgroup_event(event, ctx, false); |
e5d1367f | 1660 | |
cdd6c482 IM |
1661 | ctx->nr_events--; |
1662 | if (event->attr.inherit_stat) | |
bfbd3381 | 1663 | ctx->nr_stat--; |
8bc20959 | 1664 | |
cdd6c482 | 1665 | list_del_rcu(&event->event_entry); |
04289bb9 | 1666 | |
8a49542c PZ |
1667 | if (event->group_leader == event) |
1668 | list_del_init(&event->group_entry); | |
5c148194 | 1669 | |
96c21a46 | 1670 | update_group_times(event); |
b2e74a26 SE |
1671 | |
1672 | /* | |
1673 | * If event was in error state, then keep it | |
1674 | * that way, otherwise bogus counts will be | |
1675 | * returned on read(). The only way to get out | |
1676 | * of error state is by explicit re-enabling | |
1677 | * of the event | |
1678 | */ | |
1679 | if (event->state > PERF_EVENT_STATE_OFF) | |
1680 | event->state = PERF_EVENT_STATE_OFF; | |
5a3126d4 PZ |
1681 | |
1682 | ctx->generation++; | |
050735b0 PZ |
1683 | } |
1684 | ||
8a49542c | 1685 | static void perf_group_detach(struct perf_event *event) |
050735b0 PZ |
1686 | { |
1687 | struct perf_event *sibling, *tmp; | |
8a49542c PZ |
1688 | struct list_head *list = NULL; |
1689 | ||
a76a82a3 PZ |
1690 | lockdep_assert_held(&event->ctx->lock); |
1691 | ||
8a49542c PZ |
1692 | /* |
1693 | * We can have double detach due to exit/hot-unplug + close. | |
1694 | */ | |
1695 | if (!(event->attach_state & PERF_ATTACH_GROUP)) | |
1696 | return; | |
1697 | ||
1698 | event->attach_state &= ~PERF_ATTACH_GROUP; | |
1699 | ||
1700 | /* | |
1701 | * If this is a sibling, remove it from its group. | |
1702 | */ | |
1703 | if (event->group_leader != event) { | |
1704 | list_del_init(&event->group_entry); | |
1705 | event->group_leader->nr_siblings--; | |
c320c7b7 | 1706 | goto out; |
8a49542c PZ |
1707 | } |
1708 | ||
1709 | if (!list_empty(&event->group_entry)) | |
1710 | list = &event->group_entry; | |
2e2af50b | 1711 | |
04289bb9 | 1712 | /* |
cdd6c482 IM |
1713 | * If this was a group event with sibling events then |
1714 | * upgrade the siblings to singleton events by adding them | |
8a49542c | 1715 | * to whatever list we are on. |
04289bb9 | 1716 | */ |
cdd6c482 | 1717 | list_for_each_entry_safe(sibling, tmp, &event->sibling_list, group_entry) { |
8a49542c PZ |
1718 | if (list) |
1719 | list_move_tail(&sibling->group_entry, list); | |
04289bb9 | 1720 | sibling->group_leader = sibling; |
d6f962b5 FW |
1721 | |
1722 | /* Inherit group flags from the previous leader */ | |
4ff6a8de | 1723 | sibling->group_caps = event->group_caps; |
652884fe PZ |
1724 | |
1725 | WARN_ON_ONCE(sibling->ctx != event->ctx); | |
04289bb9 | 1726 | } |
c320c7b7 ACM |
1727 | |
1728 | out: | |
1729 | perf_event__header_size(event->group_leader); | |
1730 | ||
1731 | list_for_each_entry(tmp, &event->group_leader->sibling_list, group_entry) | |
1732 | perf_event__header_size(tmp); | |
04289bb9 IM |
1733 | } |
1734 | ||
fadfe7be JO |
1735 | static bool is_orphaned_event(struct perf_event *event) |
1736 | { | |
a69b0ca4 | 1737 | return event->state == PERF_EVENT_STATE_DEAD; |
fadfe7be JO |
1738 | } |
1739 | ||
2c81a647 | 1740 | static inline int __pmu_filter_match(struct perf_event *event) |
66eb579e MR |
1741 | { |
1742 | struct pmu *pmu = event->pmu; | |
1743 | return pmu->filter_match ? pmu->filter_match(event) : 1; | |
1744 | } | |
1745 | ||
2c81a647 MR |
1746 | /* |
1747 | * Check whether we should attempt to schedule an event group based on | |
1748 | * PMU-specific filtering. An event group can consist of HW and SW events, | |
1749 | * potentially with a SW leader, so we must check all the filters, to | |
1750 | * determine whether a group is schedulable: | |
1751 | */ | |
1752 | static inline int pmu_filter_match(struct perf_event *event) | |
1753 | { | |
1754 | struct perf_event *child; | |
1755 | ||
1756 | if (!__pmu_filter_match(event)) | |
1757 | return 0; | |
1758 | ||
1759 | list_for_each_entry(child, &event->sibling_list, group_entry) { | |
1760 | if (!__pmu_filter_match(child)) | |
1761 | return 0; | |
1762 | } | |
1763 | ||
1764 | return 1; | |
1765 | } | |
1766 | ||
fa66f07a SE |
1767 | static inline int |
1768 | event_filter_match(struct perf_event *event) | |
1769 | { | |
0b8f1e2e PZ |
1770 | return (event->cpu == -1 || event->cpu == smp_processor_id()) && |
1771 | perf_cgroup_match(event) && pmu_filter_match(event); | |
fa66f07a SE |
1772 | } |
1773 | ||
9ffcfa6f SE |
1774 | static void |
1775 | event_sched_out(struct perf_event *event, | |
3b6f9e5c | 1776 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 1777 | struct perf_event_context *ctx) |
3b6f9e5c | 1778 | { |
4158755d | 1779 | u64 tstamp = perf_event_time(event); |
fa66f07a | 1780 | u64 delta; |
652884fe PZ |
1781 | |
1782 | WARN_ON_ONCE(event->ctx != ctx); | |
1783 | lockdep_assert_held(&ctx->lock); | |
1784 | ||
fa66f07a SE |
1785 | /* |
1786 | * An event which could not be activated because of | |
1787 | * filter mismatch still needs to have its timings | |
1788 | * maintained, otherwise bogus information is return | |
1789 | * via read() for time_enabled, time_running: | |
1790 | */ | |
0b8f1e2e PZ |
1791 | if (event->state == PERF_EVENT_STATE_INACTIVE && |
1792 | !event_filter_match(event)) { | |
e5d1367f | 1793 | delta = tstamp - event->tstamp_stopped; |
fa66f07a | 1794 | event->tstamp_running += delta; |
4158755d | 1795 | event->tstamp_stopped = tstamp; |
fa66f07a SE |
1796 | } |
1797 | ||
cdd6c482 | 1798 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
9ffcfa6f | 1799 | return; |
3b6f9e5c | 1800 | |
44377277 AS |
1801 | perf_pmu_disable(event->pmu); |
1802 | ||
28a967c3 PZ |
1803 | event->tstamp_stopped = tstamp; |
1804 | event->pmu->del(event, 0); | |
1805 | event->oncpu = -1; | |
cdd6c482 IM |
1806 | event->state = PERF_EVENT_STATE_INACTIVE; |
1807 | if (event->pending_disable) { | |
1808 | event->pending_disable = 0; | |
1809 | event->state = PERF_EVENT_STATE_OFF; | |
970892a9 | 1810 | } |
3b6f9e5c | 1811 | |
cdd6c482 | 1812 | if (!is_software_event(event)) |
3b6f9e5c | 1813 | cpuctx->active_oncpu--; |
2fde4f94 MR |
1814 | if (!--ctx->nr_active) |
1815 | perf_event_ctx_deactivate(ctx); | |
0f5a2601 PZ |
1816 | if (event->attr.freq && event->attr.sample_freq) |
1817 | ctx->nr_freq--; | |
cdd6c482 | 1818 | if (event->attr.exclusive || !cpuctx->active_oncpu) |
3b6f9e5c | 1819 | cpuctx->exclusive = 0; |
44377277 AS |
1820 | |
1821 | perf_pmu_enable(event->pmu); | |
3b6f9e5c PM |
1822 | } |
1823 | ||
d859e29f | 1824 | static void |
cdd6c482 | 1825 | group_sched_out(struct perf_event *group_event, |
d859e29f | 1826 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 1827 | struct perf_event_context *ctx) |
d859e29f | 1828 | { |
cdd6c482 | 1829 | struct perf_event *event; |
fa66f07a | 1830 | int state = group_event->state; |
d859e29f | 1831 | |
3f005e7d MR |
1832 | perf_pmu_disable(ctx->pmu); |
1833 | ||
cdd6c482 | 1834 | event_sched_out(group_event, cpuctx, ctx); |
d859e29f PM |
1835 | |
1836 | /* | |
1837 | * Schedule out siblings (if any): | |
1838 | */ | |
cdd6c482 IM |
1839 | list_for_each_entry(event, &group_event->sibling_list, group_entry) |
1840 | event_sched_out(event, cpuctx, ctx); | |
d859e29f | 1841 | |
3f005e7d MR |
1842 | perf_pmu_enable(ctx->pmu); |
1843 | ||
fa66f07a | 1844 | if (state == PERF_EVENT_STATE_ACTIVE && group_event->attr.exclusive) |
d859e29f PM |
1845 | cpuctx->exclusive = 0; |
1846 | } | |
1847 | ||
45a0e07a | 1848 | #define DETACH_GROUP 0x01UL |
0017960f | 1849 | |
0793a61d | 1850 | /* |
cdd6c482 | 1851 | * Cross CPU call to remove a performance event |
0793a61d | 1852 | * |
cdd6c482 | 1853 | * We disable the event on the hardware level first. After that we |
0793a61d TG |
1854 | * remove it from the context list. |
1855 | */ | |
fae3fde6 PZ |
1856 | static void |
1857 | __perf_remove_from_context(struct perf_event *event, | |
1858 | struct perf_cpu_context *cpuctx, | |
1859 | struct perf_event_context *ctx, | |
1860 | void *info) | |
0793a61d | 1861 | { |
45a0e07a | 1862 | unsigned long flags = (unsigned long)info; |
0793a61d | 1863 | |
cdd6c482 | 1864 | event_sched_out(event, cpuctx, ctx); |
45a0e07a | 1865 | if (flags & DETACH_GROUP) |
46ce0fe9 | 1866 | perf_group_detach(event); |
cdd6c482 | 1867 | list_del_event(event, ctx); |
39a43640 PZ |
1868 | |
1869 | if (!ctx->nr_events && ctx->is_active) { | |
64ce3126 | 1870 | ctx->is_active = 0; |
39a43640 PZ |
1871 | if (ctx->task) { |
1872 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
1873 | cpuctx->task_ctx = NULL; | |
1874 | } | |
64ce3126 | 1875 | } |
0793a61d TG |
1876 | } |
1877 | ||
0793a61d | 1878 | /* |
cdd6c482 | 1879 | * Remove the event from a task's (or a CPU's) list of events. |
0793a61d | 1880 | * |
cdd6c482 IM |
1881 | * If event->ctx is a cloned context, callers must make sure that |
1882 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 PM |
1883 | * remains valid. This is OK when called from perf_release since |
1884 | * that only calls us on the top-level context, which can't be a clone. | |
cdd6c482 | 1885 | * When called from perf_event_exit_task, it's OK because the |
c93f7669 | 1886 | * context has been detached from its task. |
0793a61d | 1887 | */ |
45a0e07a | 1888 | static void perf_remove_from_context(struct perf_event *event, unsigned long flags) |
0793a61d | 1889 | { |
a76a82a3 PZ |
1890 | struct perf_event_context *ctx = event->ctx; |
1891 | ||
1892 | lockdep_assert_held(&ctx->mutex); | |
0793a61d | 1893 | |
45a0e07a | 1894 | event_function_call(event, __perf_remove_from_context, (void *)flags); |
a76a82a3 PZ |
1895 | |
1896 | /* | |
1897 | * The above event_function_call() can NO-OP when it hits | |
1898 | * TASK_TOMBSTONE. In that case we must already have been detached | |
1899 | * from the context (by perf_event_exit_event()) but the grouping | |
1900 | * might still be in-tact. | |
1901 | */ | |
1902 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); | |
1903 | if ((flags & DETACH_GROUP) && | |
1904 | (event->attach_state & PERF_ATTACH_GROUP)) { | |
1905 | /* | |
1906 | * Since in that case we cannot possibly be scheduled, simply | |
1907 | * detach now. | |
1908 | */ | |
1909 | raw_spin_lock_irq(&ctx->lock); | |
1910 | perf_group_detach(event); | |
1911 | raw_spin_unlock_irq(&ctx->lock); | |
1912 | } | |
0793a61d TG |
1913 | } |
1914 | ||
d859e29f | 1915 | /* |
cdd6c482 | 1916 | * Cross CPU call to disable a performance event |
d859e29f | 1917 | */ |
fae3fde6 PZ |
1918 | static void __perf_event_disable(struct perf_event *event, |
1919 | struct perf_cpu_context *cpuctx, | |
1920 | struct perf_event_context *ctx, | |
1921 | void *info) | |
7b648018 | 1922 | { |
fae3fde6 PZ |
1923 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
1924 | return; | |
7b648018 | 1925 | |
fae3fde6 PZ |
1926 | update_context_time(ctx); |
1927 | update_cgrp_time_from_event(event); | |
1928 | update_group_times(event); | |
1929 | if (event == event->group_leader) | |
1930 | group_sched_out(event, cpuctx, ctx); | |
1931 | else | |
1932 | event_sched_out(event, cpuctx, ctx); | |
1933 | event->state = PERF_EVENT_STATE_OFF; | |
7b648018 PZ |
1934 | } |
1935 | ||
d859e29f | 1936 | /* |
cdd6c482 | 1937 | * Disable a event. |
c93f7669 | 1938 | * |
cdd6c482 IM |
1939 | * If event->ctx is a cloned context, callers must make sure that |
1940 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 1941 | * remains valid. This condition is satisifed when called through |
cdd6c482 IM |
1942 | * perf_event_for_each_child or perf_event_for_each because they |
1943 | * hold the top-level event's child_mutex, so any descendant that | |
8ba289b8 PZ |
1944 | * goes to exit will block in perf_event_exit_event(). |
1945 | * | |
cdd6c482 | 1946 | * When called from perf_pending_event it's OK because event->ctx |
c93f7669 | 1947 | * is the current context on this CPU and preemption is disabled, |
cdd6c482 | 1948 | * hence we can't get into perf_event_task_sched_out for this context. |
d859e29f | 1949 | */ |
f63a8daa | 1950 | static void _perf_event_disable(struct perf_event *event) |
d859e29f | 1951 | { |
cdd6c482 | 1952 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 1953 | |
e625cce1 | 1954 | raw_spin_lock_irq(&ctx->lock); |
7b648018 | 1955 | if (event->state <= PERF_EVENT_STATE_OFF) { |
e625cce1 | 1956 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 1957 | return; |
53cfbf59 | 1958 | } |
e625cce1 | 1959 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 1960 | |
fae3fde6 PZ |
1961 | event_function_call(event, __perf_event_disable, NULL); |
1962 | } | |
1963 | ||
1964 | void perf_event_disable_local(struct perf_event *event) | |
1965 | { | |
1966 | event_function_local(event, __perf_event_disable, NULL); | |
d859e29f | 1967 | } |
f63a8daa PZ |
1968 | |
1969 | /* | |
1970 | * Strictly speaking kernel users cannot create groups and therefore this | |
1971 | * interface does not need the perf_event_ctx_lock() magic. | |
1972 | */ | |
1973 | void perf_event_disable(struct perf_event *event) | |
1974 | { | |
1975 | struct perf_event_context *ctx; | |
1976 | ||
1977 | ctx = perf_event_ctx_lock(event); | |
1978 | _perf_event_disable(event); | |
1979 | perf_event_ctx_unlock(event, ctx); | |
1980 | } | |
dcfce4a0 | 1981 | EXPORT_SYMBOL_GPL(perf_event_disable); |
d859e29f | 1982 | |
5aab90ce JO |
1983 | void perf_event_disable_inatomic(struct perf_event *event) |
1984 | { | |
1985 | event->pending_disable = 1; | |
1986 | irq_work_queue(&event->pending); | |
1987 | } | |
1988 | ||
e5d1367f SE |
1989 | static void perf_set_shadow_time(struct perf_event *event, |
1990 | struct perf_event_context *ctx, | |
1991 | u64 tstamp) | |
1992 | { | |
1993 | /* | |
1994 | * use the correct time source for the time snapshot | |
1995 | * | |
1996 | * We could get by without this by leveraging the | |
1997 | * fact that to get to this function, the caller | |
1998 | * has most likely already called update_context_time() | |
1999 | * and update_cgrp_time_xx() and thus both timestamp | |
2000 | * are identical (or very close). Given that tstamp is, | |
2001 | * already adjusted for cgroup, we could say that: | |
2002 | * tstamp - ctx->timestamp | |
2003 | * is equivalent to | |
2004 | * tstamp - cgrp->timestamp. | |
2005 | * | |
2006 | * Then, in perf_output_read(), the calculation would | |
2007 | * work with no changes because: | |
2008 | * - event is guaranteed scheduled in | |
2009 | * - no scheduled out in between | |
2010 | * - thus the timestamp would be the same | |
2011 | * | |
2012 | * But this is a bit hairy. | |
2013 | * | |
2014 | * So instead, we have an explicit cgroup call to remain | |
2015 | * within the time time source all along. We believe it | |
2016 | * is cleaner and simpler to understand. | |
2017 | */ | |
2018 | if (is_cgroup_event(event)) | |
2019 | perf_cgroup_set_shadow_time(event, tstamp); | |
2020 | else | |
2021 | event->shadow_ctx_time = tstamp - ctx->timestamp; | |
2022 | } | |
2023 | ||
4fe757dd PZ |
2024 | #define MAX_INTERRUPTS (~0ULL) |
2025 | ||
2026 | static void perf_log_throttle(struct perf_event *event, int enable); | |
ec0d7729 | 2027 | static void perf_log_itrace_start(struct perf_event *event); |
4fe757dd | 2028 | |
235c7fc7 | 2029 | static int |
9ffcfa6f | 2030 | event_sched_in(struct perf_event *event, |
235c7fc7 | 2031 | struct perf_cpu_context *cpuctx, |
6e37738a | 2032 | struct perf_event_context *ctx) |
235c7fc7 | 2033 | { |
4158755d | 2034 | u64 tstamp = perf_event_time(event); |
44377277 | 2035 | int ret = 0; |
4158755d | 2036 | |
63342411 PZ |
2037 | lockdep_assert_held(&ctx->lock); |
2038 | ||
cdd6c482 | 2039 | if (event->state <= PERF_EVENT_STATE_OFF) |
235c7fc7 IM |
2040 | return 0; |
2041 | ||
95ff4ca2 AS |
2042 | WRITE_ONCE(event->oncpu, smp_processor_id()); |
2043 | /* | |
2044 | * Order event::oncpu write to happen before the ACTIVE state | |
2045 | * is visible. | |
2046 | */ | |
2047 | smp_wmb(); | |
2048 | WRITE_ONCE(event->state, PERF_EVENT_STATE_ACTIVE); | |
4fe757dd PZ |
2049 | |
2050 | /* | |
2051 | * Unthrottle events, since we scheduled we might have missed several | |
2052 | * ticks already, also for a heavily scheduling task there is little | |
2053 | * guarantee it'll get a tick in a timely manner. | |
2054 | */ | |
2055 | if (unlikely(event->hw.interrupts == MAX_INTERRUPTS)) { | |
2056 | perf_log_throttle(event, 1); | |
2057 | event->hw.interrupts = 0; | |
2058 | } | |
2059 | ||
235c7fc7 IM |
2060 | /* |
2061 | * The new state must be visible before we turn it on in the hardware: | |
2062 | */ | |
2063 | smp_wmb(); | |
2064 | ||
44377277 AS |
2065 | perf_pmu_disable(event->pmu); |
2066 | ||
72f669c0 SL |
2067 | perf_set_shadow_time(event, ctx, tstamp); |
2068 | ||
ec0d7729 AS |
2069 | perf_log_itrace_start(event); |
2070 | ||
a4eaf7f1 | 2071 | if (event->pmu->add(event, PERF_EF_START)) { |
cdd6c482 IM |
2072 | event->state = PERF_EVENT_STATE_INACTIVE; |
2073 | event->oncpu = -1; | |
44377277 AS |
2074 | ret = -EAGAIN; |
2075 | goto out; | |
235c7fc7 IM |
2076 | } |
2077 | ||
00a2916f PZ |
2078 | event->tstamp_running += tstamp - event->tstamp_stopped; |
2079 | ||
cdd6c482 | 2080 | if (!is_software_event(event)) |
3b6f9e5c | 2081 | cpuctx->active_oncpu++; |
2fde4f94 MR |
2082 | if (!ctx->nr_active++) |
2083 | perf_event_ctx_activate(ctx); | |
0f5a2601 PZ |
2084 | if (event->attr.freq && event->attr.sample_freq) |
2085 | ctx->nr_freq++; | |
235c7fc7 | 2086 | |
cdd6c482 | 2087 | if (event->attr.exclusive) |
3b6f9e5c PM |
2088 | cpuctx->exclusive = 1; |
2089 | ||
44377277 AS |
2090 | out: |
2091 | perf_pmu_enable(event->pmu); | |
2092 | ||
2093 | return ret; | |
235c7fc7 IM |
2094 | } |
2095 | ||
6751b71e | 2096 | static int |
cdd6c482 | 2097 | group_sched_in(struct perf_event *group_event, |
6751b71e | 2098 | struct perf_cpu_context *cpuctx, |
6e37738a | 2099 | struct perf_event_context *ctx) |
6751b71e | 2100 | { |
6bde9b6c | 2101 | struct perf_event *event, *partial_group = NULL; |
4a234593 | 2102 | struct pmu *pmu = ctx->pmu; |
d7842da4 SE |
2103 | u64 now = ctx->time; |
2104 | bool simulate = false; | |
6751b71e | 2105 | |
cdd6c482 | 2106 | if (group_event->state == PERF_EVENT_STATE_OFF) |
6751b71e PM |
2107 | return 0; |
2108 | ||
fbbe0701 | 2109 | pmu->start_txn(pmu, PERF_PMU_TXN_ADD); |
6bde9b6c | 2110 | |
9ffcfa6f | 2111 | if (event_sched_in(group_event, cpuctx, ctx)) { |
ad5133b7 | 2112 | pmu->cancel_txn(pmu); |
272325c4 | 2113 | perf_mux_hrtimer_restart(cpuctx); |
6751b71e | 2114 | return -EAGAIN; |
90151c35 | 2115 | } |
6751b71e PM |
2116 | |
2117 | /* | |
2118 | * Schedule in siblings as one group (if any): | |
2119 | */ | |
cdd6c482 | 2120 | list_for_each_entry(event, &group_event->sibling_list, group_entry) { |
9ffcfa6f | 2121 | if (event_sched_in(event, cpuctx, ctx)) { |
cdd6c482 | 2122 | partial_group = event; |
6751b71e PM |
2123 | goto group_error; |
2124 | } | |
2125 | } | |
2126 | ||
9ffcfa6f | 2127 | if (!pmu->commit_txn(pmu)) |
6e85158c | 2128 | return 0; |
9ffcfa6f | 2129 | |
6751b71e PM |
2130 | group_error: |
2131 | /* | |
2132 | * Groups can be scheduled in as one unit only, so undo any | |
2133 | * partial group before returning: | |
d7842da4 SE |
2134 | * The events up to the failed event are scheduled out normally, |
2135 | * tstamp_stopped will be updated. | |
2136 | * | |
2137 | * The failed events and the remaining siblings need to have | |
2138 | * their timings updated as if they had gone thru event_sched_in() | |
2139 | * and event_sched_out(). This is required to get consistent timings | |
2140 | * across the group. This also takes care of the case where the group | |
2141 | * could never be scheduled by ensuring tstamp_stopped is set to mark | |
2142 | * the time the event was actually stopped, such that time delta | |
2143 | * calculation in update_event_times() is correct. | |
6751b71e | 2144 | */ |
cdd6c482 IM |
2145 | list_for_each_entry(event, &group_event->sibling_list, group_entry) { |
2146 | if (event == partial_group) | |
d7842da4 SE |
2147 | simulate = true; |
2148 | ||
2149 | if (simulate) { | |
2150 | event->tstamp_running += now - event->tstamp_stopped; | |
2151 | event->tstamp_stopped = now; | |
2152 | } else { | |
2153 | event_sched_out(event, cpuctx, ctx); | |
2154 | } | |
6751b71e | 2155 | } |
9ffcfa6f | 2156 | event_sched_out(group_event, cpuctx, ctx); |
6751b71e | 2157 | |
ad5133b7 | 2158 | pmu->cancel_txn(pmu); |
90151c35 | 2159 | |
272325c4 | 2160 | perf_mux_hrtimer_restart(cpuctx); |
9e630205 | 2161 | |
6751b71e PM |
2162 | return -EAGAIN; |
2163 | } | |
2164 | ||
3b6f9e5c | 2165 | /* |
cdd6c482 | 2166 | * Work out whether we can put this event group on the CPU now. |
3b6f9e5c | 2167 | */ |
cdd6c482 | 2168 | static int group_can_go_on(struct perf_event *event, |
3b6f9e5c PM |
2169 | struct perf_cpu_context *cpuctx, |
2170 | int can_add_hw) | |
2171 | { | |
2172 | /* | |
cdd6c482 | 2173 | * Groups consisting entirely of software events can always go on. |
3b6f9e5c | 2174 | */ |
4ff6a8de | 2175 | if (event->group_caps & PERF_EV_CAP_SOFTWARE) |
3b6f9e5c PM |
2176 | return 1; |
2177 | /* | |
2178 | * If an exclusive group is already on, no other hardware | |
cdd6c482 | 2179 | * events can go on. |
3b6f9e5c PM |
2180 | */ |
2181 | if (cpuctx->exclusive) | |
2182 | return 0; | |
2183 | /* | |
2184 | * If this group is exclusive and there are already | |
cdd6c482 | 2185 | * events on the CPU, it can't go on. |
3b6f9e5c | 2186 | */ |
cdd6c482 | 2187 | if (event->attr.exclusive && cpuctx->active_oncpu) |
3b6f9e5c PM |
2188 | return 0; |
2189 | /* | |
2190 | * Otherwise, try to add it if all previous groups were able | |
2191 | * to go on. | |
2192 | */ | |
2193 | return can_add_hw; | |
2194 | } | |
2195 | ||
cdd6c482 IM |
2196 | static void add_event_to_ctx(struct perf_event *event, |
2197 | struct perf_event_context *ctx) | |
53cfbf59 | 2198 | { |
4158755d SE |
2199 | u64 tstamp = perf_event_time(event); |
2200 | ||
cdd6c482 | 2201 | list_add_event(event, ctx); |
8a49542c | 2202 | perf_group_attach(event); |
4158755d SE |
2203 | event->tstamp_enabled = tstamp; |
2204 | event->tstamp_running = tstamp; | |
2205 | event->tstamp_stopped = tstamp; | |
53cfbf59 PM |
2206 | } |
2207 | ||
bd2afa49 PZ |
2208 | static void ctx_sched_out(struct perf_event_context *ctx, |
2209 | struct perf_cpu_context *cpuctx, | |
2210 | enum event_type_t event_type); | |
2c29ef0f PZ |
2211 | static void |
2212 | ctx_sched_in(struct perf_event_context *ctx, | |
2213 | struct perf_cpu_context *cpuctx, | |
2214 | enum event_type_t event_type, | |
2215 | struct task_struct *task); | |
fe4b04fa | 2216 | |
bd2afa49 PZ |
2217 | static void task_ctx_sched_out(struct perf_cpu_context *cpuctx, |
2218 | struct perf_event_context *ctx) | |
2219 | { | |
2220 | if (!cpuctx->task_ctx) | |
2221 | return; | |
2222 | ||
2223 | if (WARN_ON_ONCE(ctx != cpuctx->task_ctx)) | |
2224 | return; | |
2225 | ||
2226 | ctx_sched_out(ctx, cpuctx, EVENT_ALL); | |
2227 | } | |
2228 | ||
dce5855b PZ |
2229 | static void perf_event_sched_in(struct perf_cpu_context *cpuctx, |
2230 | struct perf_event_context *ctx, | |
2231 | struct task_struct *task) | |
2232 | { | |
2233 | cpu_ctx_sched_in(cpuctx, EVENT_PINNED, task); | |
2234 | if (ctx) | |
2235 | ctx_sched_in(ctx, cpuctx, EVENT_PINNED, task); | |
2236 | cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE, task); | |
2237 | if (ctx) | |
2238 | ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE, task); | |
2239 | } | |
2240 | ||
3e349507 PZ |
2241 | static void ctx_resched(struct perf_cpu_context *cpuctx, |
2242 | struct perf_event_context *task_ctx) | |
0017960f | 2243 | { |
3e349507 PZ |
2244 | perf_pmu_disable(cpuctx->ctx.pmu); |
2245 | if (task_ctx) | |
2246 | task_ctx_sched_out(cpuctx, task_ctx); | |
2247 | cpu_ctx_sched_out(cpuctx, EVENT_ALL); | |
2248 | perf_event_sched_in(cpuctx, task_ctx, current); | |
2249 | perf_pmu_enable(cpuctx->ctx.pmu); | |
0017960f PZ |
2250 | } |
2251 | ||
0793a61d | 2252 | /* |
cdd6c482 | 2253 | * Cross CPU call to install and enable a performance event |
682076ae | 2254 | * |
a096309b PZ |
2255 | * Very similar to remote_function() + event_function() but cannot assume that |
2256 | * things like ctx->is_active and cpuctx->task_ctx are set. | |
0793a61d | 2257 | */ |
fe4b04fa | 2258 | static int __perf_install_in_context(void *info) |
0793a61d | 2259 | { |
a096309b PZ |
2260 | struct perf_event *event = info; |
2261 | struct perf_event_context *ctx = event->ctx; | |
108b02cf | 2262 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
2c29ef0f | 2263 | struct perf_event_context *task_ctx = cpuctx->task_ctx; |
63cae12b | 2264 | bool reprogram = true; |
a096309b | 2265 | int ret = 0; |
0793a61d | 2266 | |
63b6da39 | 2267 | raw_spin_lock(&cpuctx->ctx.lock); |
39a43640 | 2268 | if (ctx->task) { |
b58f6b0d PZ |
2269 | raw_spin_lock(&ctx->lock); |
2270 | task_ctx = ctx; | |
a096309b | 2271 | |
63cae12b | 2272 | reprogram = (ctx->task == current); |
b58f6b0d | 2273 | |
39a43640 | 2274 | /* |
63cae12b PZ |
2275 | * If the task is running, it must be running on this CPU, |
2276 | * otherwise we cannot reprogram things. | |
2277 | * | |
2278 | * If its not running, we don't care, ctx->lock will | |
2279 | * serialize against it becoming runnable. | |
39a43640 | 2280 | */ |
63cae12b PZ |
2281 | if (task_curr(ctx->task) && !reprogram) { |
2282 | ret = -ESRCH; | |
2283 | goto unlock; | |
2284 | } | |
a096309b | 2285 | |
63cae12b | 2286 | WARN_ON_ONCE(reprogram && cpuctx->task_ctx && cpuctx->task_ctx != ctx); |
63b6da39 PZ |
2287 | } else if (task_ctx) { |
2288 | raw_spin_lock(&task_ctx->lock); | |
2c29ef0f | 2289 | } |
b58f6b0d | 2290 | |
63cae12b | 2291 | if (reprogram) { |
a096309b PZ |
2292 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
2293 | add_event_to_ctx(event, ctx); | |
2294 | ctx_resched(cpuctx, task_ctx); | |
2295 | } else { | |
2296 | add_event_to_ctx(event, ctx); | |
2297 | } | |
2298 | ||
63b6da39 | 2299 | unlock: |
2c29ef0f | 2300 | perf_ctx_unlock(cpuctx, task_ctx); |
fe4b04fa | 2301 | |
a096309b | 2302 | return ret; |
0793a61d TG |
2303 | } |
2304 | ||
2305 | /* | |
a096309b PZ |
2306 | * Attach a performance event to a context. |
2307 | * | |
2308 | * Very similar to event_function_call, see comment there. | |
0793a61d TG |
2309 | */ |
2310 | static void | |
cdd6c482 IM |
2311 | perf_install_in_context(struct perf_event_context *ctx, |
2312 | struct perf_event *event, | |
0793a61d TG |
2313 | int cpu) |
2314 | { | |
a096309b | 2315 | struct task_struct *task = READ_ONCE(ctx->task); |
39a43640 | 2316 | |
fe4b04fa PZ |
2317 | lockdep_assert_held(&ctx->mutex); |
2318 | ||
0cda4c02 YZ |
2319 | if (event->cpu != -1) |
2320 | event->cpu = cpu; | |
c3f00c70 | 2321 | |
0b8f1e2e PZ |
2322 | /* |
2323 | * Ensures that if we can observe event->ctx, both the event and ctx | |
2324 | * will be 'complete'. See perf_iterate_sb_cpu(). | |
2325 | */ | |
2326 | smp_store_release(&event->ctx, ctx); | |
2327 | ||
a096309b PZ |
2328 | if (!task) { |
2329 | cpu_function_call(cpu, __perf_install_in_context, event); | |
2330 | return; | |
2331 | } | |
2332 | ||
2333 | /* | |
2334 | * Should not happen, we validate the ctx is still alive before calling. | |
2335 | */ | |
2336 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) | |
2337 | return; | |
2338 | ||
39a43640 PZ |
2339 | /* |
2340 | * Installing events is tricky because we cannot rely on ctx->is_active | |
2341 | * to be set in case this is the nr_events 0 -> 1 transition. | |
63cae12b PZ |
2342 | * |
2343 | * Instead we use task_curr(), which tells us if the task is running. | |
2344 | * However, since we use task_curr() outside of rq::lock, we can race | |
2345 | * against the actual state. This means the result can be wrong. | |
2346 | * | |
2347 | * If we get a false positive, we retry, this is harmless. | |
2348 | * | |
2349 | * If we get a false negative, things are complicated. If we are after | |
2350 | * perf_event_context_sched_in() ctx::lock will serialize us, and the | |
2351 | * value must be correct. If we're before, it doesn't matter since | |
2352 | * perf_event_context_sched_in() will program the counter. | |
2353 | * | |
2354 | * However, this hinges on the remote context switch having observed | |
2355 | * our task->perf_event_ctxp[] store, such that it will in fact take | |
2356 | * ctx::lock in perf_event_context_sched_in(). | |
2357 | * | |
2358 | * We do this by task_function_call(), if the IPI fails to hit the task | |
2359 | * we know any future context switch of task must see the | |
2360 | * perf_event_ctpx[] store. | |
39a43640 | 2361 | */ |
63cae12b | 2362 | |
63b6da39 | 2363 | /* |
63cae12b PZ |
2364 | * This smp_mb() orders the task->perf_event_ctxp[] store with the |
2365 | * task_cpu() load, such that if the IPI then does not find the task | |
2366 | * running, a future context switch of that task must observe the | |
2367 | * store. | |
63b6da39 | 2368 | */ |
63cae12b PZ |
2369 | smp_mb(); |
2370 | again: | |
2371 | if (!task_function_call(task, __perf_install_in_context, event)) | |
a096309b PZ |
2372 | return; |
2373 | ||
2374 | raw_spin_lock_irq(&ctx->lock); | |
2375 | task = ctx->task; | |
84c4e620 | 2376 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) { |
a096309b PZ |
2377 | /* |
2378 | * Cannot happen because we already checked above (which also | |
2379 | * cannot happen), and we hold ctx->mutex, which serializes us | |
2380 | * against perf_event_exit_task_context(). | |
2381 | */ | |
63b6da39 PZ |
2382 | raw_spin_unlock_irq(&ctx->lock); |
2383 | return; | |
2384 | } | |
39a43640 | 2385 | /* |
63cae12b PZ |
2386 | * If the task is not running, ctx->lock will avoid it becoming so, |
2387 | * thus we can safely install the event. | |
39a43640 | 2388 | */ |
63cae12b PZ |
2389 | if (task_curr(task)) { |
2390 | raw_spin_unlock_irq(&ctx->lock); | |
2391 | goto again; | |
2392 | } | |
2393 | add_event_to_ctx(event, ctx); | |
2394 | raw_spin_unlock_irq(&ctx->lock); | |
0793a61d TG |
2395 | } |
2396 | ||
fa289bec | 2397 | /* |
cdd6c482 | 2398 | * Put a event into inactive state and update time fields. |
fa289bec PM |
2399 | * Enabling the leader of a group effectively enables all |
2400 | * the group members that aren't explicitly disabled, so we | |
2401 | * have to update their ->tstamp_enabled also. | |
2402 | * Note: this works for group members as well as group leaders | |
2403 | * since the non-leader members' sibling_lists will be empty. | |
2404 | */ | |
1d9b482e | 2405 | static void __perf_event_mark_enabled(struct perf_event *event) |
fa289bec | 2406 | { |
cdd6c482 | 2407 | struct perf_event *sub; |
4158755d | 2408 | u64 tstamp = perf_event_time(event); |
fa289bec | 2409 | |
cdd6c482 | 2410 | event->state = PERF_EVENT_STATE_INACTIVE; |
4158755d | 2411 | event->tstamp_enabled = tstamp - event->total_time_enabled; |
9ed6060d | 2412 | list_for_each_entry(sub, &event->sibling_list, group_entry) { |
4158755d SE |
2413 | if (sub->state >= PERF_EVENT_STATE_INACTIVE) |
2414 | sub->tstamp_enabled = tstamp - sub->total_time_enabled; | |
9ed6060d | 2415 | } |
fa289bec PM |
2416 | } |
2417 | ||
d859e29f | 2418 | /* |
cdd6c482 | 2419 | * Cross CPU call to enable a performance event |
d859e29f | 2420 | */ |
fae3fde6 PZ |
2421 | static void __perf_event_enable(struct perf_event *event, |
2422 | struct perf_cpu_context *cpuctx, | |
2423 | struct perf_event_context *ctx, | |
2424 | void *info) | |
04289bb9 | 2425 | { |
cdd6c482 | 2426 | struct perf_event *leader = event->group_leader; |
fae3fde6 | 2427 | struct perf_event_context *task_ctx; |
04289bb9 | 2428 | |
6e801e01 PZ |
2429 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2430 | event->state <= PERF_EVENT_STATE_ERROR) | |
fae3fde6 | 2431 | return; |
3cbed429 | 2432 | |
bd2afa49 PZ |
2433 | if (ctx->is_active) |
2434 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); | |
2435 | ||
1d9b482e | 2436 | __perf_event_mark_enabled(event); |
04289bb9 | 2437 | |
fae3fde6 PZ |
2438 | if (!ctx->is_active) |
2439 | return; | |
2440 | ||
e5d1367f | 2441 | if (!event_filter_match(event)) { |
bd2afa49 | 2442 | if (is_cgroup_event(event)) |
e5d1367f | 2443 | perf_cgroup_defer_enabled(event); |
bd2afa49 | 2444 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); |
fae3fde6 | 2445 | return; |
e5d1367f | 2446 | } |
f4c4176f | 2447 | |
04289bb9 | 2448 | /* |
cdd6c482 | 2449 | * If the event is in a group and isn't the group leader, |
d859e29f | 2450 | * then don't put it on unless the group is on. |
04289bb9 | 2451 | */ |
bd2afa49 PZ |
2452 | if (leader != event && leader->state != PERF_EVENT_STATE_ACTIVE) { |
2453 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
fae3fde6 | 2454 | return; |
bd2afa49 | 2455 | } |
fe4b04fa | 2456 | |
fae3fde6 PZ |
2457 | task_ctx = cpuctx->task_ctx; |
2458 | if (ctx->task) | |
2459 | WARN_ON_ONCE(task_ctx != ctx); | |
d859e29f | 2460 | |
fae3fde6 | 2461 | ctx_resched(cpuctx, task_ctx); |
7b648018 PZ |
2462 | } |
2463 | ||
d859e29f | 2464 | /* |
cdd6c482 | 2465 | * Enable a event. |
c93f7669 | 2466 | * |
cdd6c482 IM |
2467 | * If event->ctx is a cloned context, callers must make sure that |
2468 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 2469 | * remains valid. This condition is satisfied when called through |
cdd6c482 IM |
2470 | * perf_event_for_each_child or perf_event_for_each as described |
2471 | * for perf_event_disable. | |
d859e29f | 2472 | */ |
f63a8daa | 2473 | static void _perf_event_enable(struct perf_event *event) |
d859e29f | 2474 | { |
cdd6c482 | 2475 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 2476 | |
7b648018 | 2477 | raw_spin_lock_irq(&ctx->lock); |
6e801e01 PZ |
2478 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2479 | event->state < PERF_EVENT_STATE_ERROR) { | |
7b648018 | 2480 | raw_spin_unlock_irq(&ctx->lock); |
d859e29f PM |
2481 | return; |
2482 | } | |
2483 | ||
d859e29f | 2484 | /* |
cdd6c482 | 2485 | * If the event is in error state, clear that first. |
7b648018 PZ |
2486 | * |
2487 | * That way, if we see the event in error state below, we know that it | |
2488 | * has gone back into error state, as distinct from the task having | |
2489 | * been scheduled away before the cross-call arrived. | |
d859e29f | 2490 | */ |
cdd6c482 IM |
2491 | if (event->state == PERF_EVENT_STATE_ERROR) |
2492 | event->state = PERF_EVENT_STATE_OFF; | |
e625cce1 | 2493 | raw_spin_unlock_irq(&ctx->lock); |
fe4b04fa | 2494 | |
fae3fde6 | 2495 | event_function_call(event, __perf_event_enable, NULL); |
d859e29f | 2496 | } |
f63a8daa PZ |
2497 | |
2498 | /* | |
2499 | * See perf_event_disable(); | |
2500 | */ | |
2501 | void perf_event_enable(struct perf_event *event) | |
2502 | { | |
2503 | struct perf_event_context *ctx; | |
2504 | ||
2505 | ctx = perf_event_ctx_lock(event); | |
2506 | _perf_event_enable(event); | |
2507 | perf_event_ctx_unlock(event, ctx); | |
2508 | } | |
dcfce4a0 | 2509 | EXPORT_SYMBOL_GPL(perf_event_enable); |
d859e29f | 2510 | |
375637bc AS |
2511 | struct stop_event_data { |
2512 | struct perf_event *event; | |
2513 | unsigned int restart; | |
2514 | }; | |
2515 | ||
95ff4ca2 AS |
2516 | static int __perf_event_stop(void *info) |
2517 | { | |
375637bc AS |
2518 | struct stop_event_data *sd = info; |
2519 | struct perf_event *event = sd->event; | |
95ff4ca2 | 2520 | |
375637bc | 2521 | /* if it's already INACTIVE, do nothing */ |
95ff4ca2 AS |
2522 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) |
2523 | return 0; | |
2524 | ||
2525 | /* matches smp_wmb() in event_sched_in() */ | |
2526 | smp_rmb(); | |
2527 | ||
2528 | /* | |
2529 | * There is a window with interrupts enabled before we get here, | |
2530 | * so we need to check again lest we try to stop another CPU's event. | |
2531 | */ | |
2532 | if (READ_ONCE(event->oncpu) != smp_processor_id()) | |
2533 | return -EAGAIN; | |
2534 | ||
2535 | event->pmu->stop(event, PERF_EF_UPDATE); | |
2536 | ||
375637bc AS |
2537 | /* |
2538 | * May race with the actual stop (through perf_pmu_output_stop()), | |
2539 | * but it is only used for events with AUX ring buffer, and such | |
2540 | * events will refuse to restart because of rb::aux_mmap_count==0, | |
2541 | * see comments in perf_aux_output_begin(). | |
2542 | * | |
2543 | * Since this is happening on a event-local CPU, no trace is lost | |
2544 | * while restarting. | |
2545 | */ | |
2546 | if (sd->restart) | |
c9bbdd48 | 2547 | event->pmu->start(event, 0); |
375637bc | 2548 | |
95ff4ca2 AS |
2549 | return 0; |
2550 | } | |
2551 | ||
767ae086 | 2552 | static int perf_event_stop(struct perf_event *event, int restart) |
375637bc AS |
2553 | { |
2554 | struct stop_event_data sd = { | |
2555 | .event = event, | |
767ae086 | 2556 | .restart = restart, |
375637bc AS |
2557 | }; |
2558 | int ret = 0; | |
2559 | ||
2560 | do { | |
2561 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) | |
2562 | return 0; | |
2563 | ||
2564 | /* matches smp_wmb() in event_sched_in() */ | |
2565 | smp_rmb(); | |
2566 | ||
2567 | /* | |
2568 | * We only want to restart ACTIVE events, so if the event goes | |
2569 | * inactive here (event->oncpu==-1), there's nothing more to do; | |
2570 | * fall through with ret==-ENXIO. | |
2571 | */ | |
2572 | ret = cpu_function_call(READ_ONCE(event->oncpu), | |
2573 | __perf_event_stop, &sd); | |
2574 | } while (ret == -EAGAIN); | |
2575 | ||
2576 | return ret; | |
2577 | } | |
2578 | ||
2579 | /* | |
2580 | * In order to contain the amount of racy and tricky in the address filter | |
2581 | * configuration management, it is a two part process: | |
2582 | * | |
2583 | * (p1) when userspace mappings change as a result of (1) or (2) or (3) below, | |
2584 | * we update the addresses of corresponding vmas in | |
2585 | * event::addr_filters_offs array and bump the event::addr_filters_gen; | |
2586 | * (p2) when an event is scheduled in (pmu::add), it calls | |
2587 | * perf_event_addr_filters_sync() which calls pmu::addr_filters_sync() | |
2588 | * if the generation has changed since the previous call. | |
2589 | * | |
2590 | * If (p1) happens while the event is active, we restart it to force (p2). | |
2591 | * | |
2592 | * (1) perf_addr_filters_apply(): adjusting filters' offsets based on | |
2593 | * pre-existing mappings, called once when new filters arrive via SET_FILTER | |
2594 | * ioctl; | |
2595 | * (2) perf_addr_filters_adjust(): adjusting filters' offsets based on newly | |
2596 | * registered mapping, called for every new mmap(), with mm::mmap_sem down | |
2597 | * for reading; | |
2598 | * (3) perf_event_addr_filters_exec(): clearing filters' offsets in the process | |
2599 | * of exec. | |
2600 | */ | |
2601 | void perf_event_addr_filters_sync(struct perf_event *event) | |
2602 | { | |
2603 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
2604 | ||
2605 | if (!has_addr_filter(event)) | |
2606 | return; | |
2607 | ||
2608 | raw_spin_lock(&ifh->lock); | |
2609 | if (event->addr_filters_gen != event->hw.addr_filters_gen) { | |
2610 | event->pmu->addr_filters_sync(event); | |
2611 | event->hw.addr_filters_gen = event->addr_filters_gen; | |
2612 | } | |
2613 | raw_spin_unlock(&ifh->lock); | |
2614 | } | |
2615 | EXPORT_SYMBOL_GPL(perf_event_addr_filters_sync); | |
2616 | ||
f63a8daa | 2617 | static int _perf_event_refresh(struct perf_event *event, int refresh) |
79f14641 | 2618 | { |
2023b359 | 2619 | /* |
cdd6c482 | 2620 | * not supported on inherited events |
2023b359 | 2621 | */ |
2e939d1d | 2622 | if (event->attr.inherit || !is_sampling_event(event)) |
2023b359 PZ |
2623 | return -EINVAL; |
2624 | ||
cdd6c482 | 2625 | atomic_add(refresh, &event->event_limit); |
f63a8daa | 2626 | _perf_event_enable(event); |
2023b359 PZ |
2627 | |
2628 | return 0; | |
79f14641 | 2629 | } |
f63a8daa PZ |
2630 | |
2631 | /* | |
2632 | * See perf_event_disable() | |
2633 | */ | |
2634 | int perf_event_refresh(struct perf_event *event, int refresh) | |
2635 | { | |
2636 | struct perf_event_context *ctx; | |
2637 | int ret; | |
2638 | ||
2639 | ctx = perf_event_ctx_lock(event); | |
2640 | ret = _perf_event_refresh(event, refresh); | |
2641 | perf_event_ctx_unlock(event, ctx); | |
2642 | ||
2643 | return ret; | |
2644 | } | |
26ca5c11 | 2645 | EXPORT_SYMBOL_GPL(perf_event_refresh); |
79f14641 | 2646 | |
5b0311e1 FW |
2647 | static void ctx_sched_out(struct perf_event_context *ctx, |
2648 | struct perf_cpu_context *cpuctx, | |
2649 | enum event_type_t event_type) | |
235c7fc7 | 2650 | { |
db24d33e | 2651 | int is_active = ctx->is_active; |
c994d613 | 2652 | struct perf_event *event; |
235c7fc7 | 2653 | |
c994d613 | 2654 | lockdep_assert_held(&ctx->lock); |
235c7fc7 | 2655 | |
39a43640 PZ |
2656 | if (likely(!ctx->nr_events)) { |
2657 | /* | |
2658 | * See __perf_remove_from_context(). | |
2659 | */ | |
2660 | WARN_ON_ONCE(ctx->is_active); | |
2661 | if (ctx->task) | |
2662 | WARN_ON_ONCE(cpuctx->task_ctx); | |
facc4307 | 2663 | return; |
39a43640 PZ |
2664 | } |
2665 | ||
db24d33e | 2666 | ctx->is_active &= ~event_type; |
3cbaa590 PZ |
2667 | if (!(ctx->is_active & EVENT_ALL)) |
2668 | ctx->is_active = 0; | |
2669 | ||
63e30d3e PZ |
2670 | if (ctx->task) { |
2671 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
2672 | if (!ctx->is_active) | |
2673 | cpuctx->task_ctx = NULL; | |
2674 | } | |
facc4307 | 2675 | |
8fdc6539 PZ |
2676 | /* |
2677 | * Always update time if it was set; not only when it changes. | |
2678 | * Otherwise we can 'forget' to update time for any but the last | |
2679 | * context we sched out. For example: | |
2680 | * | |
2681 | * ctx_sched_out(.event_type = EVENT_FLEXIBLE) | |
2682 | * ctx_sched_out(.event_type = EVENT_PINNED) | |
2683 | * | |
2684 | * would only update time for the pinned events. | |
2685 | */ | |
3cbaa590 PZ |
2686 | if (is_active & EVENT_TIME) { |
2687 | /* update (and stop) ctx time */ | |
2688 | update_context_time(ctx); | |
2689 | update_cgrp_time_from_cpuctx(cpuctx); | |
2690 | } | |
2691 | ||
8fdc6539 PZ |
2692 | is_active ^= ctx->is_active; /* changed bits */ |
2693 | ||
3cbaa590 | 2694 | if (!ctx->nr_active || !(is_active & EVENT_ALL)) |
facc4307 | 2695 | return; |
5b0311e1 | 2696 | |
075e0b00 | 2697 | perf_pmu_disable(ctx->pmu); |
3cbaa590 | 2698 | if (is_active & EVENT_PINNED) { |
889ff015 FW |
2699 | list_for_each_entry(event, &ctx->pinned_groups, group_entry) |
2700 | group_sched_out(event, cpuctx, ctx); | |
9ed6060d | 2701 | } |
889ff015 | 2702 | |
3cbaa590 | 2703 | if (is_active & EVENT_FLEXIBLE) { |
889ff015 | 2704 | list_for_each_entry(event, &ctx->flexible_groups, group_entry) |
8c9ed8e1 | 2705 | group_sched_out(event, cpuctx, ctx); |
9ed6060d | 2706 | } |
1b9a644f | 2707 | perf_pmu_enable(ctx->pmu); |
235c7fc7 IM |
2708 | } |
2709 | ||
564c2b21 | 2710 | /* |
5a3126d4 PZ |
2711 | * Test whether two contexts are equivalent, i.e. whether they have both been |
2712 | * cloned from the same version of the same context. | |
2713 | * | |
2714 | * Equivalence is measured using a generation number in the context that is | |
2715 | * incremented on each modification to it; see unclone_ctx(), list_add_event() | |
2716 | * and list_del_event(). | |
564c2b21 | 2717 | */ |
cdd6c482 IM |
2718 | static int context_equiv(struct perf_event_context *ctx1, |
2719 | struct perf_event_context *ctx2) | |
564c2b21 | 2720 | { |
211de6eb PZ |
2721 | lockdep_assert_held(&ctx1->lock); |
2722 | lockdep_assert_held(&ctx2->lock); | |
2723 | ||
5a3126d4 PZ |
2724 | /* Pinning disables the swap optimization */ |
2725 | if (ctx1->pin_count || ctx2->pin_count) | |
2726 | return 0; | |
2727 | ||
2728 | /* If ctx1 is the parent of ctx2 */ | |
2729 | if (ctx1 == ctx2->parent_ctx && ctx1->generation == ctx2->parent_gen) | |
2730 | return 1; | |
2731 | ||
2732 | /* If ctx2 is the parent of ctx1 */ | |
2733 | if (ctx1->parent_ctx == ctx2 && ctx1->parent_gen == ctx2->generation) | |
2734 | return 1; | |
2735 | ||
2736 | /* | |
2737 | * If ctx1 and ctx2 have the same parent; we flatten the parent | |
2738 | * hierarchy, see perf_event_init_context(). | |
2739 | */ | |
2740 | if (ctx1->parent_ctx && ctx1->parent_ctx == ctx2->parent_ctx && | |
2741 | ctx1->parent_gen == ctx2->parent_gen) | |
2742 | return 1; | |
2743 | ||
2744 | /* Unmatched */ | |
2745 | return 0; | |
564c2b21 PM |
2746 | } |
2747 | ||
cdd6c482 IM |
2748 | static void __perf_event_sync_stat(struct perf_event *event, |
2749 | struct perf_event *next_event) | |
bfbd3381 PZ |
2750 | { |
2751 | u64 value; | |
2752 | ||
cdd6c482 | 2753 | if (!event->attr.inherit_stat) |
bfbd3381 PZ |
2754 | return; |
2755 | ||
2756 | /* | |
cdd6c482 | 2757 | * Update the event value, we cannot use perf_event_read() |
bfbd3381 PZ |
2758 | * because we're in the middle of a context switch and have IRQs |
2759 | * disabled, which upsets smp_call_function_single(), however | |
cdd6c482 | 2760 | * we know the event must be on the current CPU, therefore we |
bfbd3381 PZ |
2761 | * don't need to use it. |
2762 | */ | |
cdd6c482 IM |
2763 | switch (event->state) { |
2764 | case PERF_EVENT_STATE_ACTIVE: | |
3dbebf15 PZ |
2765 | event->pmu->read(event); |
2766 | /* fall-through */ | |
bfbd3381 | 2767 | |
cdd6c482 IM |
2768 | case PERF_EVENT_STATE_INACTIVE: |
2769 | update_event_times(event); | |
bfbd3381 PZ |
2770 | break; |
2771 | ||
2772 | default: | |
2773 | break; | |
2774 | } | |
2775 | ||
2776 | /* | |
cdd6c482 | 2777 | * In order to keep per-task stats reliable we need to flip the event |
bfbd3381 PZ |
2778 | * values when we flip the contexts. |
2779 | */ | |
e7850595 PZ |
2780 | value = local64_read(&next_event->count); |
2781 | value = local64_xchg(&event->count, value); | |
2782 | local64_set(&next_event->count, value); | |
bfbd3381 | 2783 | |
cdd6c482 IM |
2784 | swap(event->total_time_enabled, next_event->total_time_enabled); |
2785 | swap(event->total_time_running, next_event->total_time_running); | |
19d2e755 | 2786 | |
bfbd3381 | 2787 | /* |
19d2e755 | 2788 | * Since we swizzled the values, update the user visible data too. |
bfbd3381 | 2789 | */ |
cdd6c482 IM |
2790 | perf_event_update_userpage(event); |
2791 | perf_event_update_userpage(next_event); | |
bfbd3381 PZ |
2792 | } |
2793 | ||
cdd6c482 IM |
2794 | static void perf_event_sync_stat(struct perf_event_context *ctx, |
2795 | struct perf_event_context *next_ctx) | |
bfbd3381 | 2796 | { |
cdd6c482 | 2797 | struct perf_event *event, *next_event; |
bfbd3381 PZ |
2798 | |
2799 | if (!ctx->nr_stat) | |
2800 | return; | |
2801 | ||
02ffdbc8 PZ |
2802 | update_context_time(ctx); |
2803 | ||
cdd6c482 IM |
2804 | event = list_first_entry(&ctx->event_list, |
2805 | struct perf_event, event_entry); | |
bfbd3381 | 2806 | |
cdd6c482 IM |
2807 | next_event = list_first_entry(&next_ctx->event_list, |
2808 | struct perf_event, event_entry); | |
bfbd3381 | 2809 | |
cdd6c482 IM |
2810 | while (&event->event_entry != &ctx->event_list && |
2811 | &next_event->event_entry != &next_ctx->event_list) { | |
bfbd3381 | 2812 | |
cdd6c482 | 2813 | __perf_event_sync_stat(event, next_event); |
bfbd3381 | 2814 | |
cdd6c482 IM |
2815 | event = list_next_entry(event, event_entry); |
2816 | next_event = list_next_entry(next_event, event_entry); | |
bfbd3381 PZ |
2817 | } |
2818 | } | |
2819 | ||
fe4b04fa PZ |
2820 | static void perf_event_context_sched_out(struct task_struct *task, int ctxn, |
2821 | struct task_struct *next) | |
0793a61d | 2822 | { |
8dc85d54 | 2823 | struct perf_event_context *ctx = task->perf_event_ctxp[ctxn]; |
cdd6c482 | 2824 | struct perf_event_context *next_ctx; |
5a3126d4 | 2825 | struct perf_event_context *parent, *next_parent; |
108b02cf | 2826 | struct perf_cpu_context *cpuctx; |
c93f7669 | 2827 | int do_switch = 1; |
0793a61d | 2828 | |
108b02cf PZ |
2829 | if (likely(!ctx)) |
2830 | return; | |
10989fb2 | 2831 | |
108b02cf PZ |
2832 | cpuctx = __get_cpu_context(ctx); |
2833 | if (!cpuctx->task_ctx) | |
0793a61d TG |
2834 | return; |
2835 | ||
c93f7669 | 2836 | rcu_read_lock(); |
8dc85d54 | 2837 | next_ctx = next->perf_event_ctxp[ctxn]; |
5a3126d4 PZ |
2838 | if (!next_ctx) |
2839 | goto unlock; | |
2840 | ||
2841 | parent = rcu_dereference(ctx->parent_ctx); | |
2842 | next_parent = rcu_dereference(next_ctx->parent_ctx); | |
2843 | ||
2844 | /* If neither context have a parent context; they cannot be clones. */ | |
802c8a61 | 2845 | if (!parent && !next_parent) |
5a3126d4 PZ |
2846 | goto unlock; |
2847 | ||
2848 | if (next_parent == ctx || next_ctx == parent || next_parent == parent) { | |
c93f7669 PM |
2849 | /* |
2850 | * Looks like the two contexts are clones, so we might be | |
2851 | * able to optimize the context switch. We lock both | |
2852 | * contexts and check that they are clones under the | |
2853 | * lock (including re-checking that neither has been | |
2854 | * uncloned in the meantime). It doesn't matter which | |
2855 | * order we take the locks because no other cpu could | |
2856 | * be trying to lock both of these tasks. | |
2857 | */ | |
e625cce1 TG |
2858 | raw_spin_lock(&ctx->lock); |
2859 | raw_spin_lock_nested(&next_ctx->lock, SINGLE_DEPTH_NESTING); | |
c93f7669 | 2860 | if (context_equiv(ctx, next_ctx)) { |
63b6da39 PZ |
2861 | WRITE_ONCE(ctx->task, next); |
2862 | WRITE_ONCE(next_ctx->task, task); | |
5a158c3c YZ |
2863 | |
2864 | swap(ctx->task_ctx_data, next_ctx->task_ctx_data); | |
2865 | ||
63b6da39 PZ |
2866 | /* |
2867 | * RCU_INIT_POINTER here is safe because we've not | |
2868 | * modified the ctx and the above modification of | |
2869 | * ctx->task and ctx->task_ctx_data are immaterial | |
2870 | * since those values are always verified under | |
2871 | * ctx->lock which we're now holding. | |
2872 | */ | |
2873 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], next_ctx); | |
2874 | RCU_INIT_POINTER(next->perf_event_ctxp[ctxn], ctx); | |
2875 | ||
c93f7669 | 2876 | do_switch = 0; |
bfbd3381 | 2877 | |
cdd6c482 | 2878 | perf_event_sync_stat(ctx, next_ctx); |
c93f7669 | 2879 | } |
e625cce1 TG |
2880 | raw_spin_unlock(&next_ctx->lock); |
2881 | raw_spin_unlock(&ctx->lock); | |
564c2b21 | 2882 | } |
5a3126d4 | 2883 | unlock: |
c93f7669 | 2884 | rcu_read_unlock(); |
564c2b21 | 2885 | |
c93f7669 | 2886 | if (do_switch) { |
facc4307 | 2887 | raw_spin_lock(&ctx->lock); |
8833d0e2 | 2888 | task_ctx_sched_out(cpuctx, ctx); |
facc4307 | 2889 | raw_spin_unlock(&ctx->lock); |
c93f7669 | 2890 | } |
0793a61d TG |
2891 | } |
2892 | ||
e48c1788 PZ |
2893 | static DEFINE_PER_CPU(struct list_head, sched_cb_list); |
2894 | ||
ba532500 YZ |
2895 | void perf_sched_cb_dec(struct pmu *pmu) |
2896 | { | |
e48c1788 PZ |
2897 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
2898 | ||
ba532500 | 2899 | this_cpu_dec(perf_sched_cb_usages); |
e48c1788 PZ |
2900 | |
2901 | if (!--cpuctx->sched_cb_usage) | |
2902 | list_del(&cpuctx->sched_cb_entry); | |
ba532500 YZ |
2903 | } |
2904 | ||
e48c1788 | 2905 | |
ba532500 YZ |
2906 | void perf_sched_cb_inc(struct pmu *pmu) |
2907 | { | |
e48c1788 PZ |
2908 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
2909 | ||
2910 | if (!cpuctx->sched_cb_usage++) | |
2911 | list_add(&cpuctx->sched_cb_entry, this_cpu_ptr(&sched_cb_list)); | |
2912 | ||
ba532500 YZ |
2913 | this_cpu_inc(perf_sched_cb_usages); |
2914 | } | |
2915 | ||
2916 | /* | |
2917 | * This function provides the context switch callback to the lower code | |
2918 | * layer. It is invoked ONLY when the context switch callback is enabled. | |
09e61b4f PZ |
2919 | * |
2920 | * This callback is relevant even to per-cpu events; for example multi event | |
2921 | * PEBS requires this to provide PID/TID information. This requires we flush | |
2922 | * all queued PEBS records before we context switch to a new task. | |
ba532500 YZ |
2923 | */ |
2924 | static void perf_pmu_sched_task(struct task_struct *prev, | |
2925 | struct task_struct *next, | |
2926 | bool sched_in) | |
2927 | { | |
2928 | struct perf_cpu_context *cpuctx; | |
2929 | struct pmu *pmu; | |
ba532500 YZ |
2930 | |
2931 | if (prev == next) | |
2932 | return; | |
2933 | ||
e48c1788 | 2934 | list_for_each_entry(cpuctx, this_cpu_ptr(&sched_cb_list), sched_cb_entry) { |
1fd7e416 | 2935 | pmu = cpuctx->ctx.pmu; /* software PMUs will not have sched_task */ |
ba532500 | 2936 | |
e48c1788 PZ |
2937 | if (WARN_ON_ONCE(!pmu->sched_task)) |
2938 | continue; | |
ba532500 | 2939 | |
e48c1788 PZ |
2940 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
2941 | perf_pmu_disable(pmu); | |
ba532500 | 2942 | |
e48c1788 | 2943 | pmu->sched_task(cpuctx->task_ctx, sched_in); |
ba532500 | 2944 | |
e48c1788 PZ |
2945 | perf_pmu_enable(pmu); |
2946 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
ba532500 | 2947 | } |
ba532500 YZ |
2948 | } |
2949 | ||
45ac1403 AH |
2950 | static void perf_event_switch(struct task_struct *task, |
2951 | struct task_struct *next_prev, bool sched_in); | |
2952 | ||
8dc85d54 PZ |
2953 | #define for_each_task_context_nr(ctxn) \ |
2954 | for ((ctxn) = 0; (ctxn) < perf_nr_task_contexts; (ctxn)++) | |
2955 | ||
2956 | /* | |
2957 | * Called from scheduler to remove the events of the current task, | |
2958 | * with interrupts disabled. | |
2959 | * | |
2960 | * We stop each event and update the event value in event->count. | |
2961 | * | |
2962 | * This does not protect us against NMI, but disable() | |
2963 | * sets the disabled bit in the control field of event _before_ | |
2964 | * accessing the event control register. If a NMI hits, then it will | |
2965 | * not restart the event. | |
2966 | */ | |
ab0cce56 JO |
2967 | void __perf_event_task_sched_out(struct task_struct *task, |
2968 | struct task_struct *next) | |
8dc85d54 PZ |
2969 | { |
2970 | int ctxn; | |
2971 | ||
ba532500 YZ |
2972 | if (__this_cpu_read(perf_sched_cb_usages)) |
2973 | perf_pmu_sched_task(task, next, false); | |
2974 | ||
45ac1403 AH |
2975 | if (atomic_read(&nr_switch_events)) |
2976 | perf_event_switch(task, next, false); | |
2977 | ||
8dc85d54 PZ |
2978 | for_each_task_context_nr(ctxn) |
2979 | perf_event_context_sched_out(task, ctxn, next); | |
e5d1367f SE |
2980 | |
2981 | /* | |
2982 | * if cgroup events exist on this CPU, then we need | |
2983 | * to check if we have to switch out PMU state. | |
2984 | * cgroup event are system-wide mode only | |
2985 | */ | |
4a32fea9 | 2986 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) |
a8d757ef | 2987 | perf_cgroup_sched_out(task, next); |
8dc85d54 PZ |
2988 | } |
2989 | ||
5b0311e1 FW |
2990 | /* |
2991 | * Called with IRQs disabled | |
2992 | */ | |
2993 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, | |
2994 | enum event_type_t event_type) | |
2995 | { | |
2996 | ctx_sched_out(&cpuctx->ctx, cpuctx, event_type); | |
04289bb9 IM |
2997 | } |
2998 | ||
235c7fc7 | 2999 | static void |
5b0311e1 | 3000 | ctx_pinned_sched_in(struct perf_event_context *ctx, |
6e37738a | 3001 | struct perf_cpu_context *cpuctx) |
0793a61d | 3002 | { |
cdd6c482 | 3003 | struct perf_event *event; |
0793a61d | 3004 | |
889ff015 FW |
3005 | list_for_each_entry(event, &ctx->pinned_groups, group_entry) { |
3006 | if (event->state <= PERF_EVENT_STATE_OFF) | |
3b6f9e5c | 3007 | continue; |
5632ab12 | 3008 | if (!event_filter_match(event)) |
3b6f9e5c PM |
3009 | continue; |
3010 | ||
e5d1367f SE |
3011 | /* may need to reset tstamp_enabled */ |
3012 | if (is_cgroup_event(event)) | |
3013 | perf_cgroup_mark_enabled(event, ctx); | |
3014 | ||
8c9ed8e1 | 3015 | if (group_can_go_on(event, cpuctx, 1)) |
6e37738a | 3016 | group_sched_in(event, cpuctx, ctx); |
3b6f9e5c PM |
3017 | |
3018 | /* | |
3019 | * If this pinned group hasn't been scheduled, | |
3020 | * put it in error state. | |
3021 | */ | |
cdd6c482 IM |
3022 | if (event->state == PERF_EVENT_STATE_INACTIVE) { |
3023 | update_group_times(event); | |
3024 | event->state = PERF_EVENT_STATE_ERROR; | |
53cfbf59 | 3025 | } |
3b6f9e5c | 3026 | } |
5b0311e1 FW |
3027 | } |
3028 | ||
3029 | static void | |
3030 | ctx_flexible_sched_in(struct perf_event_context *ctx, | |
6e37738a | 3031 | struct perf_cpu_context *cpuctx) |
5b0311e1 FW |
3032 | { |
3033 | struct perf_event *event; | |
3034 | int can_add_hw = 1; | |
3b6f9e5c | 3035 | |
889ff015 FW |
3036 | list_for_each_entry(event, &ctx->flexible_groups, group_entry) { |
3037 | /* Ignore events in OFF or ERROR state */ | |
3038 | if (event->state <= PERF_EVENT_STATE_OFF) | |
3b6f9e5c | 3039 | continue; |
04289bb9 IM |
3040 | /* |
3041 | * Listen to the 'cpu' scheduling filter constraint | |
cdd6c482 | 3042 | * of events: |
04289bb9 | 3043 | */ |
5632ab12 | 3044 | if (!event_filter_match(event)) |
0793a61d TG |
3045 | continue; |
3046 | ||
e5d1367f SE |
3047 | /* may need to reset tstamp_enabled */ |
3048 | if (is_cgroup_event(event)) | |
3049 | perf_cgroup_mark_enabled(event, ctx); | |
3050 | ||
9ed6060d | 3051 | if (group_can_go_on(event, cpuctx, can_add_hw)) { |
6e37738a | 3052 | if (group_sched_in(event, cpuctx, ctx)) |
dd0e6ba2 | 3053 | can_add_hw = 0; |
9ed6060d | 3054 | } |
0793a61d | 3055 | } |
5b0311e1 FW |
3056 | } |
3057 | ||
3058 | static void | |
3059 | ctx_sched_in(struct perf_event_context *ctx, | |
3060 | struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
3061 | enum event_type_t event_type, |
3062 | struct task_struct *task) | |
5b0311e1 | 3063 | { |
db24d33e | 3064 | int is_active = ctx->is_active; |
c994d613 PZ |
3065 | u64 now; |
3066 | ||
3067 | lockdep_assert_held(&ctx->lock); | |
e5d1367f | 3068 | |
5b0311e1 | 3069 | if (likely(!ctx->nr_events)) |
facc4307 | 3070 | return; |
5b0311e1 | 3071 | |
3cbaa590 | 3072 | ctx->is_active |= (event_type | EVENT_TIME); |
63e30d3e PZ |
3073 | if (ctx->task) { |
3074 | if (!is_active) | |
3075 | cpuctx->task_ctx = ctx; | |
3076 | else | |
3077 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
3078 | } | |
3079 | ||
3cbaa590 PZ |
3080 | is_active ^= ctx->is_active; /* changed bits */ |
3081 | ||
3082 | if (is_active & EVENT_TIME) { | |
3083 | /* start ctx time */ | |
3084 | now = perf_clock(); | |
3085 | ctx->timestamp = now; | |
3086 | perf_cgroup_set_timestamp(task, ctx); | |
3087 | } | |
3088 | ||
5b0311e1 FW |
3089 | /* |
3090 | * First go through the list and put on any pinned groups | |
3091 | * in order to give them the best chance of going on. | |
3092 | */ | |
3cbaa590 | 3093 | if (is_active & EVENT_PINNED) |
6e37738a | 3094 | ctx_pinned_sched_in(ctx, cpuctx); |
5b0311e1 FW |
3095 | |
3096 | /* Then walk through the lower prio flexible groups */ | |
3cbaa590 | 3097 | if (is_active & EVENT_FLEXIBLE) |
6e37738a | 3098 | ctx_flexible_sched_in(ctx, cpuctx); |
235c7fc7 IM |
3099 | } |
3100 | ||
329c0e01 | 3101 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, |
e5d1367f SE |
3102 | enum event_type_t event_type, |
3103 | struct task_struct *task) | |
329c0e01 FW |
3104 | { |
3105 | struct perf_event_context *ctx = &cpuctx->ctx; | |
3106 | ||
e5d1367f | 3107 | ctx_sched_in(ctx, cpuctx, event_type, task); |
329c0e01 FW |
3108 | } |
3109 | ||
e5d1367f SE |
3110 | static void perf_event_context_sched_in(struct perf_event_context *ctx, |
3111 | struct task_struct *task) | |
235c7fc7 | 3112 | { |
108b02cf | 3113 | struct perf_cpu_context *cpuctx; |
235c7fc7 | 3114 | |
108b02cf | 3115 | cpuctx = __get_cpu_context(ctx); |
329c0e01 FW |
3116 | if (cpuctx->task_ctx == ctx) |
3117 | return; | |
3118 | ||
facc4307 | 3119 | perf_ctx_lock(cpuctx, ctx); |
1b9a644f | 3120 | perf_pmu_disable(ctx->pmu); |
329c0e01 FW |
3121 | /* |
3122 | * We want to keep the following priority order: | |
3123 | * cpu pinned (that don't need to move), task pinned, | |
3124 | * cpu flexible, task flexible. | |
fe45bafb AS |
3125 | * |
3126 | * However, if task's ctx is not carrying any pinned | |
3127 | * events, no need to flip the cpuctx's events around. | |
329c0e01 | 3128 | */ |
fe45bafb AS |
3129 | if (!list_empty(&ctx->pinned_groups)) |
3130 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
63e30d3e | 3131 | perf_event_sched_in(cpuctx, ctx, task); |
facc4307 PZ |
3132 | perf_pmu_enable(ctx->pmu); |
3133 | perf_ctx_unlock(cpuctx, ctx); | |
235c7fc7 IM |
3134 | } |
3135 | ||
8dc85d54 PZ |
3136 | /* |
3137 | * Called from scheduler to add the events of the current task | |
3138 | * with interrupts disabled. | |
3139 | * | |
3140 | * We restore the event value and then enable it. | |
3141 | * | |
3142 | * This does not protect us against NMI, but enable() | |
3143 | * sets the enabled bit in the control field of event _before_ | |
3144 | * accessing the event control register. If a NMI hits, then it will | |
3145 | * keep the event running. | |
3146 | */ | |
ab0cce56 JO |
3147 | void __perf_event_task_sched_in(struct task_struct *prev, |
3148 | struct task_struct *task) | |
8dc85d54 PZ |
3149 | { |
3150 | struct perf_event_context *ctx; | |
3151 | int ctxn; | |
3152 | ||
7e41d177 PZ |
3153 | /* |
3154 | * If cgroup events exist on this CPU, then we need to check if we have | |
3155 | * to switch in PMU state; cgroup event are system-wide mode only. | |
3156 | * | |
3157 | * Since cgroup events are CPU events, we must schedule these in before | |
3158 | * we schedule in the task events. | |
3159 | */ | |
3160 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) | |
3161 | perf_cgroup_sched_in(prev, task); | |
3162 | ||
8dc85d54 PZ |
3163 | for_each_task_context_nr(ctxn) { |
3164 | ctx = task->perf_event_ctxp[ctxn]; | |
3165 | if (likely(!ctx)) | |
3166 | continue; | |
3167 | ||
e5d1367f | 3168 | perf_event_context_sched_in(ctx, task); |
8dc85d54 | 3169 | } |
d010b332 | 3170 | |
45ac1403 AH |
3171 | if (atomic_read(&nr_switch_events)) |
3172 | perf_event_switch(task, prev, true); | |
3173 | ||
ba532500 YZ |
3174 | if (__this_cpu_read(perf_sched_cb_usages)) |
3175 | perf_pmu_sched_task(prev, task, true); | |
235c7fc7 IM |
3176 | } |
3177 | ||
abd50713 PZ |
3178 | static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count) |
3179 | { | |
3180 | u64 frequency = event->attr.sample_freq; | |
3181 | u64 sec = NSEC_PER_SEC; | |
3182 | u64 divisor, dividend; | |
3183 | ||
3184 | int count_fls, nsec_fls, frequency_fls, sec_fls; | |
3185 | ||
3186 | count_fls = fls64(count); | |
3187 | nsec_fls = fls64(nsec); | |
3188 | frequency_fls = fls64(frequency); | |
3189 | sec_fls = 30; | |
3190 | ||
3191 | /* | |
3192 | * We got @count in @nsec, with a target of sample_freq HZ | |
3193 | * the target period becomes: | |
3194 | * | |
3195 | * @count * 10^9 | |
3196 | * period = ------------------- | |
3197 | * @nsec * sample_freq | |
3198 | * | |
3199 | */ | |
3200 | ||
3201 | /* | |
3202 | * Reduce accuracy by one bit such that @a and @b converge | |
3203 | * to a similar magnitude. | |
3204 | */ | |
fe4b04fa | 3205 | #define REDUCE_FLS(a, b) \ |
abd50713 PZ |
3206 | do { \ |
3207 | if (a##_fls > b##_fls) { \ | |
3208 | a >>= 1; \ | |
3209 | a##_fls--; \ | |
3210 | } else { \ | |
3211 | b >>= 1; \ | |
3212 | b##_fls--; \ | |
3213 | } \ | |
3214 | } while (0) | |
3215 | ||
3216 | /* | |
3217 | * Reduce accuracy until either term fits in a u64, then proceed with | |
3218 | * the other, so that finally we can do a u64/u64 division. | |
3219 | */ | |
3220 | while (count_fls + sec_fls > 64 && nsec_fls + frequency_fls > 64) { | |
3221 | REDUCE_FLS(nsec, frequency); | |
3222 | REDUCE_FLS(sec, count); | |
3223 | } | |
3224 | ||
3225 | if (count_fls + sec_fls > 64) { | |
3226 | divisor = nsec * frequency; | |
3227 | ||
3228 | while (count_fls + sec_fls > 64) { | |
3229 | REDUCE_FLS(count, sec); | |
3230 | divisor >>= 1; | |
3231 | } | |
3232 | ||
3233 | dividend = count * sec; | |
3234 | } else { | |
3235 | dividend = count * sec; | |
3236 | ||
3237 | while (nsec_fls + frequency_fls > 64) { | |
3238 | REDUCE_FLS(nsec, frequency); | |
3239 | dividend >>= 1; | |
3240 | } | |
3241 | ||
3242 | divisor = nsec * frequency; | |
3243 | } | |
3244 | ||
f6ab91ad PZ |
3245 | if (!divisor) |
3246 | return dividend; | |
3247 | ||
abd50713 PZ |
3248 | return div64_u64(dividend, divisor); |
3249 | } | |
3250 | ||
e050e3f0 SE |
3251 | static DEFINE_PER_CPU(int, perf_throttled_count); |
3252 | static DEFINE_PER_CPU(u64, perf_throttled_seq); | |
3253 | ||
f39d47ff | 3254 | static void perf_adjust_period(struct perf_event *event, u64 nsec, u64 count, bool disable) |
bd2b5b12 | 3255 | { |
cdd6c482 | 3256 | struct hw_perf_event *hwc = &event->hw; |
f6ab91ad | 3257 | s64 period, sample_period; |
bd2b5b12 PZ |
3258 | s64 delta; |
3259 | ||
abd50713 | 3260 | period = perf_calculate_period(event, nsec, count); |
bd2b5b12 PZ |
3261 | |
3262 | delta = (s64)(period - hwc->sample_period); | |
3263 | delta = (delta + 7) / 8; /* low pass filter */ | |
3264 | ||
3265 | sample_period = hwc->sample_period + delta; | |
3266 | ||
3267 | if (!sample_period) | |
3268 | sample_period = 1; | |
3269 | ||
bd2b5b12 | 3270 | hwc->sample_period = sample_period; |
abd50713 | 3271 | |
e7850595 | 3272 | if (local64_read(&hwc->period_left) > 8*sample_period) { |
f39d47ff SE |
3273 | if (disable) |
3274 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3275 | ||
e7850595 | 3276 | local64_set(&hwc->period_left, 0); |
f39d47ff SE |
3277 | |
3278 | if (disable) | |
3279 | event->pmu->start(event, PERF_EF_RELOAD); | |
abd50713 | 3280 | } |
bd2b5b12 PZ |
3281 | } |
3282 | ||
e050e3f0 SE |
3283 | /* |
3284 | * combine freq adjustment with unthrottling to avoid two passes over the | |
3285 | * events. At the same time, make sure, having freq events does not change | |
3286 | * the rate of unthrottling as that would introduce bias. | |
3287 | */ | |
3288 | static void perf_adjust_freq_unthr_context(struct perf_event_context *ctx, | |
3289 | int needs_unthr) | |
60db5e09 | 3290 | { |
cdd6c482 IM |
3291 | struct perf_event *event; |
3292 | struct hw_perf_event *hwc; | |
e050e3f0 | 3293 | u64 now, period = TICK_NSEC; |
abd50713 | 3294 | s64 delta; |
60db5e09 | 3295 | |
e050e3f0 SE |
3296 | /* |
3297 | * only need to iterate over all events iff: | |
3298 | * - context have events in frequency mode (needs freq adjust) | |
3299 | * - there are events to unthrottle on this cpu | |
3300 | */ | |
3301 | if (!(ctx->nr_freq || needs_unthr)) | |
0f5a2601 PZ |
3302 | return; |
3303 | ||
e050e3f0 | 3304 | raw_spin_lock(&ctx->lock); |
f39d47ff | 3305 | perf_pmu_disable(ctx->pmu); |
e050e3f0 | 3306 | |
03541f8b | 3307 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { |
cdd6c482 | 3308 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
60db5e09 PZ |
3309 | continue; |
3310 | ||
5632ab12 | 3311 | if (!event_filter_match(event)) |
5d27c23d PZ |
3312 | continue; |
3313 | ||
44377277 AS |
3314 | perf_pmu_disable(event->pmu); |
3315 | ||
cdd6c482 | 3316 | hwc = &event->hw; |
6a24ed6c | 3317 | |
ae23bff1 | 3318 | if (hwc->interrupts == MAX_INTERRUPTS) { |
e050e3f0 | 3319 | hwc->interrupts = 0; |
cdd6c482 | 3320 | perf_log_throttle(event, 1); |
a4eaf7f1 | 3321 | event->pmu->start(event, 0); |
a78ac325 PZ |
3322 | } |
3323 | ||
cdd6c482 | 3324 | if (!event->attr.freq || !event->attr.sample_freq) |
44377277 | 3325 | goto next; |
60db5e09 | 3326 | |
e050e3f0 SE |
3327 | /* |
3328 | * stop the event and update event->count | |
3329 | */ | |
3330 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3331 | ||
e7850595 | 3332 | now = local64_read(&event->count); |
abd50713 PZ |
3333 | delta = now - hwc->freq_count_stamp; |
3334 | hwc->freq_count_stamp = now; | |
60db5e09 | 3335 | |
e050e3f0 SE |
3336 | /* |
3337 | * restart the event | |
3338 | * reload only if value has changed | |
f39d47ff SE |
3339 | * we have stopped the event so tell that |
3340 | * to perf_adjust_period() to avoid stopping it | |
3341 | * twice. | |
e050e3f0 | 3342 | */ |
abd50713 | 3343 | if (delta > 0) |
f39d47ff | 3344 | perf_adjust_period(event, period, delta, false); |
e050e3f0 SE |
3345 | |
3346 | event->pmu->start(event, delta > 0 ? PERF_EF_RELOAD : 0); | |
44377277 AS |
3347 | next: |
3348 | perf_pmu_enable(event->pmu); | |
60db5e09 | 3349 | } |
e050e3f0 | 3350 | |
f39d47ff | 3351 | perf_pmu_enable(ctx->pmu); |
e050e3f0 | 3352 | raw_spin_unlock(&ctx->lock); |
60db5e09 PZ |
3353 | } |
3354 | ||
235c7fc7 | 3355 | /* |
cdd6c482 | 3356 | * Round-robin a context's events: |
235c7fc7 | 3357 | */ |
cdd6c482 | 3358 | static void rotate_ctx(struct perf_event_context *ctx) |
0793a61d | 3359 | { |
dddd3379 TG |
3360 | /* |
3361 | * Rotate the first entry last of non-pinned groups. Rotation might be | |
3362 | * disabled by the inheritance code. | |
3363 | */ | |
3364 | if (!ctx->rotate_disable) | |
3365 | list_rotate_left(&ctx->flexible_groups); | |
235c7fc7 IM |
3366 | } |
3367 | ||
9e630205 | 3368 | static int perf_rotate_context(struct perf_cpu_context *cpuctx) |
235c7fc7 | 3369 | { |
8dc85d54 | 3370 | struct perf_event_context *ctx = NULL; |
2fde4f94 | 3371 | int rotate = 0; |
7fc23a53 | 3372 | |
b5ab4cd5 | 3373 | if (cpuctx->ctx.nr_events) { |
b5ab4cd5 PZ |
3374 | if (cpuctx->ctx.nr_events != cpuctx->ctx.nr_active) |
3375 | rotate = 1; | |
3376 | } | |
235c7fc7 | 3377 | |
8dc85d54 | 3378 | ctx = cpuctx->task_ctx; |
b5ab4cd5 | 3379 | if (ctx && ctx->nr_events) { |
b5ab4cd5 PZ |
3380 | if (ctx->nr_events != ctx->nr_active) |
3381 | rotate = 1; | |
3382 | } | |
9717e6cd | 3383 | |
e050e3f0 | 3384 | if (!rotate) |
0f5a2601 PZ |
3385 | goto done; |
3386 | ||
facc4307 | 3387 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
1b9a644f | 3388 | perf_pmu_disable(cpuctx->ctx.pmu); |
60db5e09 | 3389 | |
e050e3f0 SE |
3390 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); |
3391 | if (ctx) | |
3392 | ctx_sched_out(ctx, cpuctx, EVENT_FLEXIBLE); | |
0793a61d | 3393 | |
e050e3f0 SE |
3394 | rotate_ctx(&cpuctx->ctx); |
3395 | if (ctx) | |
3396 | rotate_ctx(ctx); | |
235c7fc7 | 3397 | |
e050e3f0 | 3398 | perf_event_sched_in(cpuctx, ctx, current); |
235c7fc7 | 3399 | |
0f5a2601 PZ |
3400 | perf_pmu_enable(cpuctx->ctx.pmu); |
3401 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
b5ab4cd5 | 3402 | done: |
9e630205 SE |
3403 | |
3404 | return rotate; | |
e9d2b064 PZ |
3405 | } |
3406 | ||
3407 | void perf_event_task_tick(void) | |
3408 | { | |
2fde4f94 MR |
3409 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
3410 | struct perf_event_context *ctx, *tmp; | |
e050e3f0 | 3411 | int throttled; |
b5ab4cd5 | 3412 | |
e9d2b064 PZ |
3413 | WARN_ON(!irqs_disabled()); |
3414 | ||
e050e3f0 SE |
3415 | __this_cpu_inc(perf_throttled_seq); |
3416 | throttled = __this_cpu_xchg(perf_throttled_count, 0); | |
555e0c1e | 3417 | tick_dep_clear_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
e050e3f0 | 3418 | |
2fde4f94 | 3419 | list_for_each_entry_safe(ctx, tmp, head, active_ctx_list) |
e050e3f0 | 3420 | perf_adjust_freq_unthr_context(ctx, throttled); |
0793a61d TG |
3421 | } |
3422 | ||
889ff015 FW |
3423 | static int event_enable_on_exec(struct perf_event *event, |
3424 | struct perf_event_context *ctx) | |
3425 | { | |
3426 | if (!event->attr.enable_on_exec) | |
3427 | return 0; | |
3428 | ||
3429 | event->attr.enable_on_exec = 0; | |
3430 | if (event->state >= PERF_EVENT_STATE_INACTIVE) | |
3431 | return 0; | |
3432 | ||
1d9b482e | 3433 | __perf_event_mark_enabled(event); |
889ff015 FW |
3434 | |
3435 | return 1; | |
3436 | } | |
3437 | ||
57e7986e | 3438 | /* |
cdd6c482 | 3439 | * Enable all of a task's events that have been marked enable-on-exec. |
57e7986e PM |
3440 | * This expects task == current. |
3441 | */ | |
c1274499 | 3442 | static void perf_event_enable_on_exec(int ctxn) |
57e7986e | 3443 | { |
c1274499 | 3444 | struct perf_event_context *ctx, *clone_ctx = NULL; |
3e349507 | 3445 | struct perf_cpu_context *cpuctx; |
cdd6c482 | 3446 | struct perf_event *event; |
57e7986e PM |
3447 | unsigned long flags; |
3448 | int enabled = 0; | |
3449 | ||
3450 | local_irq_save(flags); | |
c1274499 | 3451 | ctx = current->perf_event_ctxp[ctxn]; |
cdd6c482 | 3452 | if (!ctx || !ctx->nr_events) |
57e7986e PM |
3453 | goto out; |
3454 | ||
3e349507 PZ |
3455 | cpuctx = __get_cpu_context(ctx); |
3456 | perf_ctx_lock(cpuctx, ctx); | |
7fce2509 | 3457 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
3e349507 PZ |
3458 | list_for_each_entry(event, &ctx->event_list, event_entry) |
3459 | enabled |= event_enable_on_exec(event, ctx); | |
57e7986e PM |
3460 | |
3461 | /* | |
3e349507 | 3462 | * Unclone and reschedule this context if we enabled any event. |
57e7986e | 3463 | */ |
3e349507 | 3464 | if (enabled) { |
211de6eb | 3465 | clone_ctx = unclone_ctx(ctx); |
3e349507 PZ |
3466 | ctx_resched(cpuctx, ctx); |
3467 | } | |
3468 | perf_ctx_unlock(cpuctx, ctx); | |
57e7986e | 3469 | |
9ed6060d | 3470 | out: |
57e7986e | 3471 | local_irq_restore(flags); |
211de6eb PZ |
3472 | |
3473 | if (clone_ctx) | |
3474 | put_ctx(clone_ctx); | |
57e7986e PM |
3475 | } |
3476 | ||
0492d4c5 PZ |
3477 | struct perf_read_data { |
3478 | struct perf_event *event; | |
3479 | bool group; | |
7d88962e | 3480 | int ret; |
0492d4c5 PZ |
3481 | }; |
3482 | ||
d6a2f903 DCC |
3483 | static int find_cpu_to_read(struct perf_event *event, int local_cpu) |
3484 | { | |
3485 | int event_cpu = event->oncpu; | |
3486 | u16 local_pkg, event_pkg; | |
3487 | ||
3488 | if (event->group_caps & PERF_EV_CAP_READ_ACTIVE_PKG) { | |
3489 | event_pkg = topology_physical_package_id(event_cpu); | |
3490 | local_pkg = topology_physical_package_id(local_cpu); | |
3491 | ||
3492 | if (event_pkg == local_pkg) | |
3493 | return local_cpu; | |
3494 | } | |
3495 | ||
3496 | return event_cpu; | |
3497 | } | |
3498 | ||
0793a61d | 3499 | /* |
cdd6c482 | 3500 | * Cross CPU call to read the hardware event |
0793a61d | 3501 | */ |
cdd6c482 | 3502 | static void __perf_event_read(void *info) |
0793a61d | 3503 | { |
0492d4c5 PZ |
3504 | struct perf_read_data *data = info; |
3505 | struct perf_event *sub, *event = data->event; | |
cdd6c482 | 3506 | struct perf_event_context *ctx = event->ctx; |
108b02cf | 3507 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
4a00c16e | 3508 | struct pmu *pmu = event->pmu; |
621a01ea | 3509 | |
e1ac3614 PM |
3510 | /* |
3511 | * If this is a task context, we need to check whether it is | |
3512 | * the current task context of this cpu. If not it has been | |
3513 | * scheduled out before the smp call arrived. In that case | |
cdd6c482 IM |
3514 | * event->count would have been updated to a recent sample |
3515 | * when the event was scheduled out. | |
e1ac3614 PM |
3516 | */ |
3517 | if (ctx->task && cpuctx->task_ctx != ctx) | |
3518 | return; | |
3519 | ||
e625cce1 | 3520 | raw_spin_lock(&ctx->lock); |
e5d1367f | 3521 | if (ctx->is_active) { |
542e72fc | 3522 | update_context_time(ctx); |
e5d1367f SE |
3523 | update_cgrp_time_from_event(event); |
3524 | } | |
0492d4c5 | 3525 | |
cdd6c482 | 3526 | update_event_times(event); |
4a00c16e SB |
3527 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
3528 | goto unlock; | |
0492d4c5 | 3529 | |
4a00c16e SB |
3530 | if (!data->group) { |
3531 | pmu->read(event); | |
3532 | data->ret = 0; | |
0492d4c5 | 3533 | goto unlock; |
4a00c16e SB |
3534 | } |
3535 | ||
3536 | pmu->start_txn(pmu, PERF_PMU_TXN_READ); | |
3537 | ||
3538 | pmu->read(event); | |
0492d4c5 PZ |
3539 | |
3540 | list_for_each_entry(sub, &event->sibling_list, group_entry) { | |
3541 | update_event_times(sub); | |
4a00c16e SB |
3542 | if (sub->state == PERF_EVENT_STATE_ACTIVE) { |
3543 | /* | |
3544 | * Use sibling's PMU rather than @event's since | |
3545 | * sibling could be on different (eg: software) PMU. | |
3546 | */ | |
0492d4c5 | 3547 | sub->pmu->read(sub); |
4a00c16e | 3548 | } |
0492d4c5 | 3549 | } |
4a00c16e SB |
3550 | |
3551 | data->ret = pmu->commit_txn(pmu); | |
0492d4c5 PZ |
3552 | |
3553 | unlock: | |
e625cce1 | 3554 | raw_spin_unlock(&ctx->lock); |
0793a61d TG |
3555 | } |
3556 | ||
b5e58793 PZ |
3557 | static inline u64 perf_event_count(struct perf_event *event) |
3558 | { | |
eacd3ecc MF |
3559 | if (event->pmu->count) |
3560 | return event->pmu->count(event); | |
3561 | ||
3562 | return __perf_event_count(event); | |
b5e58793 PZ |
3563 | } |
3564 | ||
ffe8690c KX |
3565 | /* |
3566 | * NMI-safe method to read a local event, that is an event that | |
3567 | * is: | |
3568 | * - either for the current task, or for this CPU | |
3569 | * - does not have inherit set, for inherited task events | |
3570 | * will not be local and we cannot read them atomically | |
3571 | * - must not have a pmu::count method | |
3572 | */ | |
3573 | u64 perf_event_read_local(struct perf_event *event) | |
3574 | { | |
3575 | unsigned long flags; | |
3576 | u64 val; | |
3577 | ||
3578 | /* | |
3579 | * Disabling interrupts avoids all counter scheduling (context | |
3580 | * switches, timer based rotation and IPIs). | |
3581 | */ | |
3582 | local_irq_save(flags); | |
3583 | ||
3584 | /* If this is a per-task event, it must be for current */ | |
3585 | WARN_ON_ONCE((event->attach_state & PERF_ATTACH_TASK) && | |
3586 | event->hw.target != current); | |
3587 | ||
3588 | /* If this is a per-CPU event, it must be for this CPU */ | |
3589 | WARN_ON_ONCE(!(event->attach_state & PERF_ATTACH_TASK) && | |
3590 | event->cpu != smp_processor_id()); | |
3591 | ||
3592 | /* | |
3593 | * It must not be an event with inherit set, we cannot read | |
3594 | * all child counters from atomic context. | |
3595 | */ | |
3596 | WARN_ON_ONCE(event->attr.inherit); | |
3597 | ||
3598 | /* | |
3599 | * It must not have a pmu::count method, those are not | |
3600 | * NMI safe. | |
3601 | */ | |
3602 | WARN_ON_ONCE(event->pmu->count); | |
3603 | ||
3604 | /* | |
3605 | * If the event is currently on this CPU, its either a per-task event, | |
3606 | * or local to this CPU. Furthermore it means its ACTIVE (otherwise | |
3607 | * oncpu == -1). | |
3608 | */ | |
3609 | if (event->oncpu == smp_processor_id()) | |
3610 | event->pmu->read(event); | |
3611 | ||
3612 | val = local64_read(&event->count); | |
3613 | local_irq_restore(flags); | |
3614 | ||
3615 | return val; | |
3616 | } | |
3617 | ||
7d88962e | 3618 | static int perf_event_read(struct perf_event *event, bool group) |
0793a61d | 3619 | { |
d6a2f903 | 3620 | int ret = 0, cpu_to_read, local_cpu; |
7d88962e | 3621 | |
0793a61d | 3622 | /* |
cdd6c482 IM |
3623 | * If event is enabled and currently active on a CPU, update the |
3624 | * value in the event structure: | |
0793a61d | 3625 | */ |
cdd6c482 | 3626 | if (event->state == PERF_EVENT_STATE_ACTIVE) { |
0492d4c5 PZ |
3627 | struct perf_read_data data = { |
3628 | .event = event, | |
3629 | .group = group, | |
7d88962e | 3630 | .ret = 0, |
0492d4c5 | 3631 | }; |
d6a2f903 DCC |
3632 | |
3633 | local_cpu = get_cpu(); | |
3634 | cpu_to_read = find_cpu_to_read(event, local_cpu); | |
3635 | put_cpu(); | |
3636 | ||
58763148 PZ |
3637 | /* |
3638 | * Purposely ignore the smp_call_function_single() return | |
3639 | * value. | |
3640 | * | |
3641 | * If event->oncpu isn't a valid CPU it means the event got | |
3642 | * scheduled out and that will have updated the event count. | |
3643 | * | |
3644 | * Therefore, either way, we'll have an up-to-date event count | |
3645 | * after this. | |
3646 | */ | |
2cc53841 | 3647 | (void)smp_call_function_single(cpu_to_read, __perf_event_read, &data, 1); |
58763148 | 3648 | ret = data.ret; |
cdd6c482 | 3649 | } else if (event->state == PERF_EVENT_STATE_INACTIVE) { |
2b8988c9 PZ |
3650 | struct perf_event_context *ctx = event->ctx; |
3651 | unsigned long flags; | |
3652 | ||
e625cce1 | 3653 | raw_spin_lock_irqsave(&ctx->lock, flags); |
c530ccd9 SE |
3654 | /* |
3655 | * may read while context is not active | |
3656 | * (e.g., thread is blocked), in that case | |
3657 | * we cannot update context time | |
3658 | */ | |
e5d1367f | 3659 | if (ctx->is_active) { |
c530ccd9 | 3660 | update_context_time(ctx); |
e5d1367f SE |
3661 | update_cgrp_time_from_event(event); |
3662 | } | |
0492d4c5 PZ |
3663 | if (group) |
3664 | update_group_times(event); | |
3665 | else | |
3666 | update_event_times(event); | |
e625cce1 | 3667 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
0793a61d | 3668 | } |
7d88962e SB |
3669 | |
3670 | return ret; | |
0793a61d TG |
3671 | } |
3672 | ||
a63eaf34 | 3673 | /* |
cdd6c482 | 3674 | * Initialize the perf_event context in a task_struct: |
a63eaf34 | 3675 | */ |
eb184479 | 3676 | static void __perf_event_init_context(struct perf_event_context *ctx) |
a63eaf34 | 3677 | { |
e625cce1 | 3678 | raw_spin_lock_init(&ctx->lock); |
a63eaf34 | 3679 | mutex_init(&ctx->mutex); |
2fde4f94 | 3680 | INIT_LIST_HEAD(&ctx->active_ctx_list); |
889ff015 FW |
3681 | INIT_LIST_HEAD(&ctx->pinned_groups); |
3682 | INIT_LIST_HEAD(&ctx->flexible_groups); | |
a63eaf34 PM |
3683 | INIT_LIST_HEAD(&ctx->event_list); |
3684 | atomic_set(&ctx->refcount, 1); | |
eb184479 PZ |
3685 | } |
3686 | ||
3687 | static struct perf_event_context * | |
3688 | alloc_perf_context(struct pmu *pmu, struct task_struct *task) | |
3689 | { | |
3690 | struct perf_event_context *ctx; | |
3691 | ||
3692 | ctx = kzalloc(sizeof(struct perf_event_context), GFP_KERNEL); | |
3693 | if (!ctx) | |
3694 | return NULL; | |
3695 | ||
3696 | __perf_event_init_context(ctx); | |
3697 | if (task) { | |
3698 | ctx->task = task; | |
3699 | get_task_struct(task); | |
0793a61d | 3700 | } |
eb184479 PZ |
3701 | ctx->pmu = pmu; |
3702 | ||
3703 | return ctx; | |
a63eaf34 PM |
3704 | } |
3705 | ||
2ebd4ffb MH |
3706 | static struct task_struct * |
3707 | find_lively_task_by_vpid(pid_t vpid) | |
3708 | { | |
3709 | struct task_struct *task; | |
0793a61d TG |
3710 | |
3711 | rcu_read_lock(); | |
2ebd4ffb | 3712 | if (!vpid) |
0793a61d TG |
3713 | task = current; |
3714 | else | |
2ebd4ffb | 3715 | task = find_task_by_vpid(vpid); |
0793a61d TG |
3716 | if (task) |
3717 | get_task_struct(task); | |
3718 | rcu_read_unlock(); | |
3719 | ||
3720 | if (!task) | |
3721 | return ERR_PTR(-ESRCH); | |
3722 | ||
2ebd4ffb | 3723 | return task; |
2ebd4ffb MH |
3724 | } |
3725 | ||
fe4b04fa PZ |
3726 | /* |
3727 | * Returns a matching context with refcount and pincount. | |
3728 | */ | |
108b02cf | 3729 | static struct perf_event_context * |
4af57ef2 YZ |
3730 | find_get_context(struct pmu *pmu, struct task_struct *task, |
3731 | struct perf_event *event) | |
0793a61d | 3732 | { |
211de6eb | 3733 | struct perf_event_context *ctx, *clone_ctx = NULL; |
22a4f650 | 3734 | struct perf_cpu_context *cpuctx; |
4af57ef2 | 3735 | void *task_ctx_data = NULL; |
25346b93 | 3736 | unsigned long flags; |
8dc85d54 | 3737 | int ctxn, err; |
4af57ef2 | 3738 | int cpu = event->cpu; |
0793a61d | 3739 | |
22a4ec72 | 3740 | if (!task) { |
cdd6c482 | 3741 | /* Must be root to operate on a CPU event: */ |
0764771d | 3742 | if (perf_paranoid_cpu() && !capable(CAP_SYS_ADMIN)) |
0793a61d TG |
3743 | return ERR_PTR(-EACCES); |
3744 | ||
0793a61d | 3745 | /* |
cdd6c482 | 3746 | * We could be clever and allow to attach a event to an |
0793a61d TG |
3747 | * offline CPU and activate it when the CPU comes up, but |
3748 | * that's for later. | |
3749 | */ | |
f6325e30 | 3750 | if (!cpu_online(cpu)) |
0793a61d TG |
3751 | return ERR_PTR(-ENODEV); |
3752 | ||
108b02cf | 3753 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); |
0793a61d | 3754 | ctx = &cpuctx->ctx; |
c93f7669 | 3755 | get_ctx(ctx); |
fe4b04fa | 3756 | ++ctx->pin_count; |
0793a61d | 3757 | |
0793a61d TG |
3758 | return ctx; |
3759 | } | |
3760 | ||
8dc85d54 PZ |
3761 | err = -EINVAL; |
3762 | ctxn = pmu->task_ctx_nr; | |
3763 | if (ctxn < 0) | |
3764 | goto errout; | |
3765 | ||
4af57ef2 YZ |
3766 | if (event->attach_state & PERF_ATTACH_TASK_DATA) { |
3767 | task_ctx_data = kzalloc(pmu->task_ctx_size, GFP_KERNEL); | |
3768 | if (!task_ctx_data) { | |
3769 | err = -ENOMEM; | |
3770 | goto errout; | |
3771 | } | |
3772 | } | |
3773 | ||
9ed6060d | 3774 | retry: |
8dc85d54 | 3775 | ctx = perf_lock_task_context(task, ctxn, &flags); |
c93f7669 | 3776 | if (ctx) { |
211de6eb | 3777 | clone_ctx = unclone_ctx(ctx); |
fe4b04fa | 3778 | ++ctx->pin_count; |
4af57ef2 YZ |
3779 | |
3780 | if (task_ctx_data && !ctx->task_ctx_data) { | |
3781 | ctx->task_ctx_data = task_ctx_data; | |
3782 | task_ctx_data = NULL; | |
3783 | } | |
e625cce1 | 3784 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
211de6eb PZ |
3785 | |
3786 | if (clone_ctx) | |
3787 | put_ctx(clone_ctx); | |
9137fb28 | 3788 | } else { |
eb184479 | 3789 | ctx = alloc_perf_context(pmu, task); |
c93f7669 PM |
3790 | err = -ENOMEM; |
3791 | if (!ctx) | |
3792 | goto errout; | |
eb184479 | 3793 | |
4af57ef2 YZ |
3794 | if (task_ctx_data) { |
3795 | ctx->task_ctx_data = task_ctx_data; | |
3796 | task_ctx_data = NULL; | |
3797 | } | |
3798 | ||
dbe08d82 ON |
3799 | err = 0; |
3800 | mutex_lock(&task->perf_event_mutex); | |
3801 | /* | |
3802 | * If it has already passed perf_event_exit_task(). | |
3803 | * we must see PF_EXITING, it takes this mutex too. | |
3804 | */ | |
3805 | if (task->flags & PF_EXITING) | |
3806 | err = -ESRCH; | |
3807 | else if (task->perf_event_ctxp[ctxn]) | |
3808 | err = -EAGAIN; | |
fe4b04fa | 3809 | else { |
9137fb28 | 3810 | get_ctx(ctx); |
fe4b04fa | 3811 | ++ctx->pin_count; |
dbe08d82 | 3812 | rcu_assign_pointer(task->perf_event_ctxp[ctxn], ctx); |
fe4b04fa | 3813 | } |
dbe08d82 ON |
3814 | mutex_unlock(&task->perf_event_mutex); |
3815 | ||
3816 | if (unlikely(err)) { | |
9137fb28 | 3817 | put_ctx(ctx); |
dbe08d82 ON |
3818 | |
3819 | if (err == -EAGAIN) | |
3820 | goto retry; | |
3821 | goto errout; | |
a63eaf34 PM |
3822 | } |
3823 | } | |
3824 | ||
4af57ef2 | 3825 | kfree(task_ctx_data); |
0793a61d | 3826 | return ctx; |
c93f7669 | 3827 | |
9ed6060d | 3828 | errout: |
4af57ef2 | 3829 | kfree(task_ctx_data); |
c93f7669 | 3830 | return ERR_PTR(err); |
0793a61d TG |
3831 | } |
3832 | ||
6fb2915d | 3833 | static void perf_event_free_filter(struct perf_event *event); |
2541517c | 3834 | static void perf_event_free_bpf_prog(struct perf_event *event); |
6fb2915d | 3835 | |
cdd6c482 | 3836 | static void free_event_rcu(struct rcu_head *head) |
592903cd | 3837 | { |
cdd6c482 | 3838 | struct perf_event *event; |
592903cd | 3839 | |
cdd6c482 IM |
3840 | event = container_of(head, struct perf_event, rcu_head); |
3841 | if (event->ns) | |
3842 | put_pid_ns(event->ns); | |
6fb2915d | 3843 | perf_event_free_filter(event); |
cdd6c482 | 3844 | kfree(event); |
592903cd PZ |
3845 | } |
3846 | ||
b69cf536 PZ |
3847 | static void ring_buffer_attach(struct perf_event *event, |
3848 | struct ring_buffer *rb); | |
925d519a | 3849 | |
f2fb6bef KL |
3850 | static void detach_sb_event(struct perf_event *event) |
3851 | { | |
3852 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
3853 | ||
3854 | raw_spin_lock(&pel->lock); | |
3855 | list_del_rcu(&event->sb_list); | |
3856 | raw_spin_unlock(&pel->lock); | |
3857 | } | |
3858 | ||
a4f144eb | 3859 | static bool is_sb_event(struct perf_event *event) |
f2fb6bef | 3860 | { |
a4f144eb DCC |
3861 | struct perf_event_attr *attr = &event->attr; |
3862 | ||
f2fb6bef | 3863 | if (event->parent) |
a4f144eb | 3864 | return false; |
f2fb6bef KL |
3865 | |
3866 | if (event->attach_state & PERF_ATTACH_TASK) | |
a4f144eb | 3867 | return false; |
f2fb6bef | 3868 | |
a4f144eb DCC |
3869 | if (attr->mmap || attr->mmap_data || attr->mmap2 || |
3870 | attr->comm || attr->comm_exec || | |
3871 | attr->task || | |
3872 | attr->context_switch) | |
3873 | return true; | |
3874 | return false; | |
3875 | } | |
3876 | ||
3877 | static void unaccount_pmu_sb_event(struct perf_event *event) | |
3878 | { | |
3879 | if (is_sb_event(event)) | |
3880 | detach_sb_event(event); | |
f2fb6bef KL |
3881 | } |
3882 | ||
4beb31f3 | 3883 | static void unaccount_event_cpu(struct perf_event *event, int cpu) |
f1600952 | 3884 | { |
4beb31f3 FW |
3885 | if (event->parent) |
3886 | return; | |
3887 | ||
4beb31f3 FW |
3888 | if (is_cgroup_event(event)) |
3889 | atomic_dec(&per_cpu(perf_cgroup_events, cpu)); | |
3890 | } | |
925d519a | 3891 | |
555e0c1e FW |
3892 | #ifdef CONFIG_NO_HZ_FULL |
3893 | static DEFINE_SPINLOCK(nr_freq_lock); | |
3894 | #endif | |
3895 | ||
3896 | static void unaccount_freq_event_nohz(void) | |
3897 | { | |
3898 | #ifdef CONFIG_NO_HZ_FULL | |
3899 | spin_lock(&nr_freq_lock); | |
3900 | if (atomic_dec_and_test(&nr_freq_events)) | |
3901 | tick_nohz_dep_clear(TICK_DEP_BIT_PERF_EVENTS); | |
3902 | spin_unlock(&nr_freq_lock); | |
3903 | #endif | |
3904 | } | |
3905 | ||
3906 | static void unaccount_freq_event(void) | |
3907 | { | |
3908 | if (tick_nohz_full_enabled()) | |
3909 | unaccount_freq_event_nohz(); | |
3910 | else | |
3911 | atomic_dec(&nr_freq_events); | |
3912 | } | |
3913 | ||
4beb31f3 FW |
3914 | static void unaccount_event(struct perf_event *event) |
3915 | { | |
25432ae9 PZ |
3916 | bool dec = false; |
3917 | ||
4beb31f3 FW |
3918 | if (event->parent) |
3919 | return; | |
3920 | ||
3921 | if (event->attach_state & PERF_ATTACH_TASK) | |
25432ae9 | 3922 | dec = true; |
4beb31f3 FW |
3923 | if (event->attr.mmap || event->attr.mmap_data) |
3924 | atomic_dec(&nr_mmap_events); | |
3925 | if (event->attr.comm) | |
3926 | atomic_dec(&nr_comm_events); | |
3927 | if (event->attr.task) | |
3928 | atomic_dec(&nr_task_events); | |
948b26b6 | 3929 | if (event->attr.freq) |
555e0c1e | 3930 | unaccount_freq_event(); |
45ac1403 | 3931 | if (event->attr.context_switch) { |
25432ae9 | 3932 | dec = true; |
45ac1403 AH |
3933 | atomic_dec(&nr_switch_events); |
3934 | } | |
4beb31f3 | 3935 | if (is_cgroup_event(event)) |
25432ae9 | 3936 | dec = true; |
4beb31f3 | 3937 | if (has_branch_stack(event)) |
25432ae9 PZ |
3938 | dec = true; |
3939 | ||
9107c89e PZ |
3940 | if (dec) { |
3941 | if (!atomic_add_unless(&perf_sched_count, -1, 1)) | |
3942 | schedule_delayed_work(&perf_sched_work, HZ); | |
3943 | } | |
4beb31f3 FW |
3944 | |
3945 | unaccount_event_cpu(event, event->cpu); | |
f2fb6bef KL |
3946 | |
3947 | unaccount_pmu_sb_event(event); | |
4beb31f3 | 3948 | } |
925d519a | 3949 | |
9107c89e PZ |
3950 | static void perf_sched_delayed(struct work_struct *work) |
3951 | { | |
3952 | mutex_lock(&perf_sched_mutex); | |
3953 | if (atomic_dec_and_test(&perf_sched_count)) | |
3954 | static_branch_disable(&perf_sched_events); | |
3955 | mutex_unlock(&perf_sched_mutex); | |
3956 | } | |
3957 | ||
bed5b25a AS |
3958 | /* |
3959 | * The following implement mutual exclusion of events on "exclusive" pmus | |
3960 | * (PERF_PMU_CAP_EXCLUSIVE). Such pmus can only have one event scheduled | |
3961 | * at a time, so we disallow creating events that might conflict, namely: | |
3962 | * | |
3963 | * 1) cpu-wide events in the presence of per-task events, | |
3964 | * 2) per-task events in the presence of cpu-wide events, | |
3965 | * 3) two matching events on the same context. | |
3966 | * | |
3967 | * The former two cases are handled in the allocation path (perf_event_alloc(), | |
a0733e69 | 3968 | * _free_event()), the latter -- before the first perf_install_in_context(). |
bed5b25a AS |
3969 | */ |
3970 | static int exclusive_event_init(struct perf_event *event) | |
3971 | { | |
3972 | struct pmu *pmu = event->pmu; | |
3973 | ||
3974 | if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE)) | |
3975 | return 0; | |
3976 | ||
3977 | /* | |
3978 | * Prevent co-existence of per-task and cpu-wide events on the | |
3979 | * same exclusive pmu. | |
3980 | * | |
3981 | * Negative pmu::exclusive_cnt means there are cpu-wide | |
3982 | * events on this "exclusive" pmu, positive means there are | |
3983 | * per-task events. | |
3984 | * | |
3985 | * Since this is called in perf_event_alloc() path, event::ctx | |
3986 | * doesn't exist yet; it is, however, safe to use PERF_ATTACH_TASK | |
3987 | * to mean "per-task event", because unlike other attach states it | |
3988 | * never gets cleared. | |
3989 | */ | |
3990 | if (event->attach_state & PERF_ATTACH_TASK) { | |
3991 | if (!atomic_inc_unless_negative(&pmu->exclusive_cnt)) | |
3992 | return -EBUSY; | |
3993 | } else { | |
3994 | if (!atomic_dec_unless_positive(&pmu->exclusive_cnt)) | |
3995 | return -EBUSY; | |
3996 | } | |
3997 | ||
3998 | return 0; | |
3999 | } | |
4000 | ||
4001 | static void exclusive_event_destroy(struct perf_event *event) | |
4002 | { | |
4003 | struct pmu *pmu = event->pmu; | |
4004 | ||
4005 | if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE)) | |
4006 | return; | |
4007 | ||
4008 | /* see comment in exclusive_event_init() */ | |
4009 | if (event->attach_state & PERF_ATTACH_TASK) | |
4010 | atomic_dec(&pmu->exclusive_cnt); | |
4011 | else | |
4012 | atomic_inc(&pmu->exclusive_cnt); | |
4013 | } | |
4014 | ||
4015 | static bool exclusive_event_match(struct perf_event *e1, struct perf_event *e2) | |
4016 | { | |
3bf6215a | 4017 | if ((e1->pmu == e2->pmu) && |
bed5b25a AS |
4018 | (e1->cpu == e2->cpu || |
4019 | e1->cpu == -1 || | |
4020 | e2->cpu == -1)) | |
4021 | return true; | |
4022 | return false; | |
4023 | } | |
4024 | ||
4025 | /* Called under the same ctx::mutex as perf_install_in_context() */ | |
4026 | static bool exclusive_event_installable(struct perf_event *event, | |
4027 | struct perf_event_context *ctx) | |
4028 | { | |
4029 | struct perf_event *iter_event; | |
4030 | struct pmu *pmu = event->pmu; | |
4031 | ||
4032 | if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE)) | |
4033 | return true; | |
4034 | ||
4035 | list_for_each_entry(iter_event, &ctx->event_list, event_entry) { | |
4036 | if (exclusive_event_match(iter_event, event)) | |
4037 | return false; | |
4038 | } | |
4039 | ||
4040 | return true; | |
4041 | } | |
4042 | ||
375637bc AS |
4043 | static void perf_addr_filters_splice(struct perf_event *event, |
4044 | struct list_head *head); | |
4045 | ||
683ede43 | 4046 | static void _free_event(struct perf_event *event) |
f1600952 | 4047 | { |
e360adbe | 4048 | irq_work_sync(&event->pending); |
925d519a | 4049 | |
4beb31f3 | 4050 | unaccount_event(event); |
9ee318a7 | 4051 | |
76369139 | 4052 | if (event->rb) { |
9bb5d40c PZ |
4053 | /* |
4054 | * Can happen when we close an event with re-directed output. | |
4055 | * | |
4056 | * Since we have a 0 refcount, perf_mmap_close() will skip | |
4057 | * over us; possibly making our ring_buffer_put() the last. | |
4058 | */ | |
4059 | mutex_lock(&event->mmap_mutex); | |
b69cf536 | 4060 | ring_buffer_attach(event, NULL); |
9bb5d40c | 4061 | mutex_unlock(&event->mmap_mutex); |
a4be7c27 PZ |
4062 | } |
4063 | ||
e5d1367f SE |
4064 | if (is_cgroup_event(event)) |
4065 | perf_detach_cgroup(event); | |
4066 | ||
a0733e69 PZ |
4067 | if (!event->parent) { |
4068 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) | |
4069 | put_callchain_buffers(); | |
4070 | } | |
4071 | ||
4072 | perf_event_free_bpf_prog(event); | |
375637bc AS |
4073 | perf_addr_filters_splice(event, NULL); |
4074 | kfree(event->addr_filters_offs); | |
a0733e69 PZ |
4075 | |
4076 | if (event->destroy) | |
4077 | event->destroy(event); | |
4078 | ||
4079 | if (event->ctx) | |
4080 | put_ctx(event->ctx); | |
4081 | ||
62a92c8f AS |
4082 | exclusive_event_destroy(event); |
4083 | module_put(event->pmu->module); | |
a0733e69 PZ |
4084 | |
4085 | call_rcu(&event->rcu_head, free_event_rcu); | |
f1600952 PZ |
4086 | } |
4087 | ||
683ede43 PZ |
4088 | /* |
4089 | * Used to free events which have a known refcount of 1, such as in error paths | |
4090 | * where the event isn't exposed yet and inherited events. | |
4091 | */ | |
4092 | static void free_event(struct perf_event *event) | |
0793a61d | 4093 | { |
683ede43 PZ |
4094 | if (WARN(atomic_long_cmpxchg(&event->refcount, 1, 0) != 1, |
4095 | "unexpected event refcount: %ld; ptr=%p\n", | |
4096 | atomic_long_read(&event->refcount), event)) { | |
4097 | /* leak to avoid use-after-free */ | |
4098 | return; | |
4099 | } | |
0793a61d | 4100 | |
683ede43 | 4101 | _free_event(event); |
0793a61d TG |
4102 | } |
4103 | ||
a66a3052 | 4104 | /* |
f8697762 | 4105 | * Remove user event from the owner task. |
a66a3052 | 4106 | */ |
f8697762 | 4107 | static void perf_remove_from_owner(struct perf_event *event) |
fb0459d7 | 4108 | { |
8882135b | 4109 | struct task_struct *owner; |
fb0459d7 | 4110 | |
8882135b | 4111 | rcu_read_lock(); |
8882135b | 4112 | /* |
f47c02c0 PZ |
4113 | * Matches the smp_store_release() in perf_event_exit_task(). If we |
4114 | * observe !owner it means the list deletion is complete and we can | |
4115 | * indeed free this event, otherwise we need to serialize on | |
8882135b PZ |
4116 | * owner->perf_event_mutex. |
4117 | */ | |
f47c02c0 | 4118 | owner = lockless_dereference(event->owner); |
8882135b PZ |
4119 | if (owner) { |
4120 | /* | |
4121 | * Since delayed_put_task_struct() also drops the last | |
4122 | * task reference we can safely take a new reference | |
4123 | * while holding the rcu_read_lock(). | |
4124 | */ | |
4125 | get_task_struct(owner); | |
4126 | } | |
4127 | rcu_read_unlock(); | |
4128 | ||
4129 | if (owner) { | |
f63a8daa PZ |
4130 | /* |
4131 | * If we're here through perf_event_exit_task() we're already | |
4132 | * holding ctx->mutex which would be an inversion wrt. the | |
4133 | * normal lock order. | |
4134 | * | |
4135 | * However we can safely take this lock because its the child | |
4136 | * ctx->mutex. | |
4137 | */ | |
4138 | mutex_lock_nested(&owner->perf_event_mutex, SINGLE_DEPTH_NESTING); | |
4139 | ||
8882135b PZ |
4140 | /* |
4141 | * We have to re-check the event->owner field, if it is cleared | |
4142 | * we raced with perf_event_exit_task(), acquiring the mutex | |
4143 | * ensured they're done, and we can proceed with freeing the | |
4144 | * event. | |
4145 | */ | |
f47c02c0 | 4146 | if (event->owner) { |
8882135b | 4147 | list_del_init(&event->owner_entry); |
f47c02c0 PZ |
4148 | smp_store_release(&event->owner, NULL); |
4149 | } | |
8882135b PZ |
4150 | mutex_unlock(&owner->perf_event_mutex); |
4151 | put_task_struct(owner); | |
4152 | } | |
f8697762 JO |
4153 | } |
4154 | ||
f8697762 JO |
4155 | static void put_event(struct perf_event *event) |
4156 | { | |
f8697762 JO |
4157 | if (!atomic_long_dec_and_test(&event->refcount)) |
4158 | return; | |
4159 | ||
c6e5b732 PZ |
4160 | _free_event(event); |
4161 | } | |
4162 | ||
4163 | /* | |
4164 | * Kill an event dead; while event:refcount will preserve the event | |
4165 | * object, it will not preserve its functionality. Once the last 'user' | |
4166 | * gives up the object, we'll destroy the thing. | |
4167 | */ | |
4168 | int perf_event_release_kernel(struct perf_event *event) | |
4169 | { | |
a4f4bb6d | 4170 | struct perf_event_context *ctx = event->ctx; |
c6e5b732 PZ |
4171 | struct perf_event *child, *tmp; |
4172 | ||
a4f4bb6d PZ |
4173 | /* |
4174 | * If we got here through err_file: fput(event_file); we will not have | |
4175 | * attached to a context yet. | |
4176 | */ | |
4177 | if (!ctx) { | |
4178 | WARN_ON_ONCE(event->attach_state & | |
4179 | (PERF_ATTACH_CONTEXT|PERF_ATTACH_GROUP)); | |
4180 | goto no_ctx; | |
4181 | } | |
4182 | ||
f8697762 JO |
4183 | if (!is_kernel_event(event)) |
4184 | perf_remove_from_owner(event); | |
8882135b | 4185 | |
5fa7c8ec | 4186 | ctx = perf_event_ctx_lock(event); |
a83fe28e | 4187 | WARN_ON_ONCE(ctx->parent_ctx); |
a69b0ca4 | 4188 | perf_remove_from_context(event, DETACH_GROUP); |
683ede43 | 4189 | |
a69b0ca4 | 4190 | raw_spin_lock_irq(&ctx->lock); |
683ede43 | 4191 | /* |
a69b0ca4 PZ |
4192 | * Mark this even as STATE_DEAD, there is no external reference to it |
4193 | * anymore. | |
683ede43 | 4194 | * |
a69b0ca4 PZ |
4195 | * Anybody acquiring event->child_mutex after the below loop _must_ |
4196 | * also see this, most importantly inherit_event() which will avoid | |
4197 | * placing more children on the list. | |
683ede43 | 4198 | * |
c6e5b732 PZ |
4199 | * Thus this guarantees that we will in fact observe and kill _ALL_ |
4200 | * child events. | |
683ede43 | 4201 | */ |
a69b0ca4 PZ |
4202 | event->state = PERF_EVENT_STATE_DEAD; |
4203 | raw_spin_unlock_irq(&ctx->lock); | |
4204 | ||
4205 | perf_event_ctx_unlock(event, ctx); | |
683ede43 | 4206 | |
c6e5b732 PZ |
4207 | again: |
4208 | mutex_lock(&event->child_mutex); | |
4209 | list_for_each_entry(child, &event->child_list, child_list) { | |
a6fa941d | 4210 | |
c6e5b732 PZ |
4211 | /* |
4212 | * Cannot change, child events are not migrated, see the | |
4213 | * comment with perf_event_ctx_lock_nested(). | |
4214 | */ | |
4215 | ctx = lockless_dereference(child->ctx); | |
4216 | /* | |
4217 | * Since child_mutex nests inside ctx::mutex, we must jump | |
4218 | * through hoops. We start by grabbing a reference on the ctx. | |
4219 | * | |
4220 | * Since the event cannot get freed while we hold the | |
4221 | * child_mutex, the context must also exist and have a !0 | |
4222 | * reference count. | |
4223 | */ | |
4224 | get_ctx(ctx); | |
4225 | ||
4226 | /* | |
4227 | * Now that we have a ctx ref, we can drop child_mutex, and | |
4228 | * acquire ctx::mutex without fear of it going away. Then we | |
4229 | * can re-acquire child_mutex. | |
4230 | */ | |
4231 | mutex_unlock(&event->child_mutex); | |
4232 | mutex_lock(&ctx->mutex); | |
4233 | mutex_lock(&event->child_mutex); | |
4234 | ||
4235 | /* | |
4236 | * Now that we hold ctx::mutex and child_mutex, revalidate our | |
4237 | * state, if child is still the first entry, it didn't get freed | |
4238 | * and we can continue doing so. | |
4239 | */ | |
4240 | tmp = list_first_entry_or_null(&event->child_list, | |
4241 | struct perf_event, child_list); | |
4242 | if (tmp == child) { | |
4243 | perf_remove_from_context(child, DETACH_GROUP); | |
4244 | list_del(&child->child_list); | |
4245 | free_event(child); | |
4246 | /* | |
4247 | * This matches the refcount bump in inherit_event(); | |
4248 | * this can't be the last reference. | |
4249 | */ | |
4250 | put_event(event); | |
4251 | } | |
4252 | ||
4253 | mutex_unlock(&event->child_mutex); | |
4254 | mutex_unlock(&ctx->mutex); | |
4255 | put_ctx(ctx); | |
4256 | goto again; | |
4257 | } | |
4258 | mutex_unlock(&event->child_mutex); | |
4259 | ||
a4f4bb6d PZ |
4260 | no_ctx: |
4261 | put_event(event); /* Must be the 'last' reference */ | |
683ede43 PZ |
4262 | return 0; |
4263 | } | |
4264 | EXPORT_SYMBOL_GPL(perf_event_release_kernel); | |
4265 | ||
8b10c5e2 PZ |
4266 | /* |
4267 | * Called when the last reference to the file is gone. | |
4268 | */ | |
a6fa941d AV |
4269 | static int perf_release(struct inode *inode, struct file *file) |
4270 | { | |
c6e5b732 | 4271 | perf_event_release_kernel(file->private_data); |
a6fa941d | 4272 | return 0; |
fb0459d7 | 4273 | } |
fb0459d7 | 4274 | |
59ed446f | 4275 | u64 perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) |
e53c0994 | 4276 | { |
cdd6c482 | 4277 | struct perf_event *child; |
e53c0994 PZ |
4278 | u64 total = 0; |
4279 | ||
59ed446f PZ |
4280 | *enabled = 0; |
4281 | *running = 0; | |
4282 | ||
6f10581a | 4283 | mutex_lock(&event->child_mutex); |
01add3ea | 4284 | |
7d88962e | 4285 | (void)perf_event_read(event, false); |
01add3ea SB |
4286 | total += perf_event_count(event); |
4287 | ||
59ed446f PZ |
4288 | *enabled += event->total_time_enabled + |
4289 | atomic64_read(&event->child_total_time_enabled); | |
4290 | *running += event->total_time_running + | |
4291 | atomic64_read(&event->child_total_time_running); | |
4292 | ||
4293 | list_for_each_entry(child, &event->child_list, child_list) { | |
7d88962e | 4294 | (void)perf_event_read(child, false); |
01add3ea | 4295 | total += perf_event_count(child); |
59ed446f PZ |
4296 | *enabled += child->total_time_enabled; |
4297 | *running += child->total_time_running; | |
4298 | } | |
6f10581a | 4299 | mutex_unlock(&event->child_mutex); |
e53c0994 PZ |
4300 | |
4301 | return total; | |
4302 | } | |
fb0459d7 | 4303 | EXPORT_SYMBOL_GPL(perf_event_read_value); |
e53c0994 | 4304 | |
7d88962e | 4305 | static int __perf_read_group_add(struct perf_event *leader, |
fa8c2693 | 4306 | u64 read_format, u64 *values) |
3dab77fb | 4307 | { |
fa8c2693 PZ |
4308 | struct perf_event *sub; |
4309 | int n = 1; /* skip @nr */ | |
7d88962e | 4310 | int ret; |
f63a8daa | 4311 | |
7d88962e SB |
4312 | ret = perf_event_read(leader, true); |
4313 | if (ret) | |
4314 | return ret; | |
abf4868b | 4315 | |
fa8c2693 PZ |
4316 | /* |
4317 | * Since we co-schedule groups, {enabled,running} times of siblings | |
4318 | * will be identical to those of the leader, so we only publish one | |
4319 | * set. | |
4320 | */ | |
4321 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { | |
4322 | values[n++] += leader->total_time_enabled + | |
4323 | atomic64_read(&leader->child_total_time_enabled); | |
4324 | } | |
3dab77fb | 4325 | |
fa8c2693 PZ |
4326 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { |
4327 | values[n++] += leader->total_time_running + | |
4328 | atomic64_read(&leader->child_total_time_running); | |
4329 | } | |
4330 | ||
4331 | /* | |
4332 | * Write {count,id} tuples for every sibling. | |
4333 | */ | |
4334 | values[n++] += perf_event_count(leader); | |
abf4868b PZ |
4335 | if (read_format & PERF_FORMAT_ID) |
4336 | values[n++] = primary_event_id(leader); | |
3dab77fb | 4337 | |
fa8c2693 PZ |
4338 | list_for_each_entry(sub, &leader->sibling_list, group_entry) { |
4339 | values[n++] += perf_event_count(sub); | |
4340 | if (read_format & PERF_FORMAT_ID) | |
4341 | values[n++] = primary_event_id(sub); | |
4342 | } | |
7d88962e SB |
4343 | |
4344 | return 0; | |
fa8c2693 | 4345 | } |
3dab77fb | 4346 | |
fa8c2693 PZ |
4347 | static int perf_read_group(struct perf_event *event, |
4348 | u64 read_format, char __user *buf) | |
4349 | { | |
4350 | struct perf_event *leader = event->group_leader, *child; | |
4351 | struct perf_event_context *ctx = leader->ctx; | |
7d88962e | 4352 | int ret; |
fa8c2693 | 4353 | u64 *values; |
3dab77fb | 4354 | |
fa8c2693 | 4355 | lockdep_assert_held(&ctx->mutex); |
3dab77fb | 4356 | |
fa8c2693 PZ |
4357 | values = kzalloc(event->read_size, GFP_KERNEL); |
4358 | if (!values) | |
4359 | return -ENOMEM; | |
3dab77fb | 4360 | |
fa8c2693 PZ |
4361 | values[0] = 1 + leader->nr_siblings; |
4362 | ||
4363 | /* | |
4364 | * By locking the child_mutex of the leader we effectively | |
4365 | * lock the child list of all siblings.. XXX explain how. | |
4366 | */ | |
4367 | mutex_lock(&leader->child_mutex); | |
abf4868b | 4368 | |
7d88962e SB |
4369 | ret = __perf_read_group_add(leader, read_format, values); |
4370 | if (ret) | |
4371 | goto unlock; | |
4372 | ||
4373 | list_for_each_entry(child, &leader->child_list, child_list) { | |
4374 | ret = __perf_read_group_add(child, read_format, values); | |
4375 | if (ret) | |
4376 | goto unlock; | |
4377 | } | |
abf4868b | 4378 | |
fa8c2693 | 4379 | mutex_unlock(&leader->child_mutex); |
abf4868b | 4380 | |
7d88962e | 4381 | ret = event->read_size; |
fa8c2693 PZ |
4382 | if (copy_to_user(buf, values, event->read_size)) |
4383 | ret = -EFAULT; | |
7d88962e | 4384 | goto out; |
fa8c2693 | 4385 | |
7d88962e SB |
4386 | unlock: |
4387 | mutex_unlock(&leader->child_mutex); | |
4388 | out: | |
fa8c2693 | 4389 | kfree(values); |
abf4868b | 4390 | return ret; |
3dab77fb PZ |
4391 | } |
4392 | ||
b15f495b | 4393 | static int perf_read_one(struct perf_event *event, |
3dab77fb PZ |
4394 | u64 read_format, char __user *buf) |
4395 | { | |
59ed446f | 4396 | u64 enabled, running; |
3dab77fb PZ |
4397 | u64 values[4]; |
4398 | int n = 0; | |
4399 | ||
59ed446f PZ |
4400 | values[n++] = perf_event_read_value(event, &enabled, &running); |
4401 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
4402 | values[n++] = enabled; | |
4403 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
4404 | values[n++] = running; | |
3dab77fb | 4405 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 4406 | values[n++] = primary_event_id(event); |
3dab77fb PZ |
4407 | |
4408 | if (copy_to_user(buf, values, n * sizeof(u64))) | |
4409 | return -EFAULT; | |
4410 | ||
4411 | return n * sizeof(u64); | |
4412 | } | |
4413 | ||
dc633982 JO |
4414 | static bool is_event_hup(struct perf_event *event) |
4415 | { | |
4416 | bool no_children; | |
4417 | ||
a69b0ca4 | 4418 | if (event->state > PERF_EVENT_STATE_EXIT) |
dc633982 JO |
4419 | return false; |
4420 | ||
4421 | mutex_lock(&event->child_mutex); | |
4422 | no_children = list_empty(&event->child_list); | |
4423 | mutex_unlock(&event->child_mutex); | |
4424 | return no_children; | |
4425 | } | |
4426 | ||
0793a61d | 4427 | /* |
cdd6c482 | 4428 | * Read the performance event - simple non blocking version for now |
0793a61d TG |
4429 | */ |
4430 | static ssize_t | |
b15f495b | 4431 | __perf_read(struct perf_event *event, char __user *buf, size_t count) |
0793a61d | 4432 | { |
cdd6c482 | 4433 | u64 read_format = event->attr.read_format; |
3dab77fb | 4434 | int ret; |
0793a61d | 4435 | |
3b6f9e5c | 4436 | /* |
cdd6c482 | 4437 | * Return end-of-file for a read on a event that is in |
3b6f9e5c PM |
4438 | * error state (i.e. because it was pinned but it couldn't be |
4439 | * scheduled on to the CPU at some point). | |
4440 | */ | |
cdd6c482 | 4441 | if (event->state == PERF_EVENT_STATE_ERROR) |
3b6f9e5c PM |
4442 | return 0; |
4443 | ||
c320c7b7 | 4444 | if (count < event->read_size) |
3dab77fb PZ |
4445 | return -ENOSPC; |
4446 | ||
cdd6c482 | 4447 | WARN_ON_ONCE(event->ctx->parent_ctx); |
3dab77fb | 4448 | if (read_format & PERF_FORMAT_GROUP) |
b15f495b | 4449 | ret = perf_read_group(event, read_format, buf); |
3dab77fb | 4450 | else |
b15f495b | 4451 | ret = perf_read_one(event, read_format, buf); |
0793a61d | 4452 | |
3dab77fb | 4453 | return ret; |
0793a61d TG |
4454 | } |
4455 | ||
0793a61d TG |
4456 | static ssize_t |
4457 | perf_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) | |
4458 | { | |
cdd6c482 | 4459 | struct perf_event *event = file->private_data; |
f63a8daa PZ |
4460 | struct perf_event_context *ctx; |
4461 | int ret; | |
0793a61d | 4462 | |
f63a8daa | 4463 | ctx = perf_event_ctx_lock(event); |
b15f495b | 4464 | ret = __perf_read(event, buf, count); |
f63a8daa PZ |
4465 | perf_event_ctx_unlock(event, ctx); |
4466 | ||
4467 | return ret; | |
0793a61d TG |
4468 | } |
4469 | ||
4470 | static unsigned int perf_poll(struct file *file, poll_table *wait) | |
4471 | { | |
cdd6c482 | 4472 | struct perf_event *event = file->private_data; |
76369139 | 4473 | struct ring_buffer *rb; |
61b67684 | 4474 | unsigned int events = POLLHUP; |
c7138f37 | 4475 | |
e708d7ad | 4476 | poll_wait(file, &event->waitq, wait); |
179033b3 | 4477 | |
dc633982 | 4478 | if (is_event_hup(event)) |
179033b3 | 4479 | return events; |
c7138f37 | 4480 | |
10c6db11 | 4481 | /* |
9bb5d40c PZ |
4482 | * Pin the event->rb by taking event->mmap_mutex; otherwise |
4483 | * perf_event_set_output() can swizzle our rb and make us miss wakeups. | |
10c6db11 PZ |
4484 | */ |
4485 | mutex_lock(&event->mmap_mutex); | |
9bb5d40c PZ |
4486 | rb = event->rb; |
4487 | if (rb) | |
76369139 | 4488 | events = atomic_xchg(&rb->poll, 0); |
10c6db11 | 4489 | mutex_unlock(&event->mmap_mutex); |
0793a61d TG |
4490 | return events; |
4491 | } | |
4492 | ||
f63a8daa | 4493 | static void _perf_event_reset(struct perf_event *event) |
6de6a7b9 | 4494 | { |
7d88962e | 4495 | (void)perf_event_read(event, false); |
e7850595 | 4496 | local64_set(&event->count, 0); |
cdd6c482 | 4497 | perf_event_update_userpage(event); |
3df5edad PZ |
4498 | } |
4499 | ||
c93f7669 | 4500 | /* |
cdd6c482 IM |
4501 | * Holding the top-level event's child_mutex means that any |
4502 | * descendant process that has inherited this event will block | |
8ba289b8 | 4503 | * in perf_event_exit_event() if it goes to exit, thus satisfying the |
cdd6c482 | 4504 | * task existence requirements of perf_event_enable/disable. |
c93f7669 | 4505 | */ |
cdd6c482 IM |
4506 | static void perf_event_for_each_child(struct perf_event *event, |
4507 | void (*func)(struct perf_event *)) | |
3df5edad | 4508 | { |
cdd6c482 | 4509 | struct perf_event *child; |
3df5edad | 4510 | |
cdd6c482 | 4511 | WARN_ON_ONCE(event->ctx->parent_ctx); |
f63a8daa | 4512 | |
cdd6c482 IM |
4513 | mutex_lock(&event->child_mutex); |
4514 | func(event); | |
4515 | list_for_each_entry(child, &event->child_list, child_list) | |
3df5edad | 4516 | func(child); |
cdd6c482 | 4517 | mutex_unlock(&event->child_mutex); |
3df5edad PZ |
4518 | } |
4519 | ||
cdd6c482 IM |
4520 | static void perf_event_for_each(struct perf_event *event, |
4521 | void (*func)(struct perf_event *)) | |
3df5edad | 4522 | { |
cdd6c482 IM |
4523 | struct perf_event_context *ctx = event->ctx; |
4524 | struct perf_event *sibling; | |
3df5edad | 4525 | |
f63a8daa PZ |
4526 | lockdep_assert_held(&ctx->mutex); |
4527 | ||
cdd6c482 | 4528 | event = event->group_leader; |
75f937f2 | 4529 | |
cdd6c482 | 4530 | perf_event_for_each_child(event, func); |
cdd6c482 | 4531 | list_for_each_entry(sibling, &event->sibling_list, group_entry) |
724b6daa | 4532 | perf_event_for_each_child(sibling, func); |
6de6a7b9 PZ |
4533 | } |
4534 | ||
fae3fde6 PZ |
4535 | static void __perf_event_period(struct perf_event *event, |
4536 | struct perf_cpu_context *cpuctx, | |
4537 | struct perf_event_context *ctx, | |
4538 | void *info) | |
c7999c6f | 4539 | { |
fae3fde6 | 4540 | u64 value = *((u64 *)info); |
c7999c6f | 4541 | bool active; |
08247e31 | 4542 | |
cdd6c482 | 4543 | if (event->attr.freq) { |
cdd6c482 | 4544 | event->attr.sample_freq = value; |
08247e31 | 4545 | } else { |
cdd6c482 IM |
4546 | event->attr.sample_period = value; |
4547 | event->hw.sample_period = value; | |
08247e31 | 4548 | } |
bad7192b PZ |
4549 | |
4550 | active = (event->state == PERF_EVENT_STATE_ACTIVE); | |
4551 | if (active) { | |
4552 | perf_pmu_disable(ctx->pmu); | |
1e02cd40 PZ |
4553 | /* |
4554 | * We could be throttled; unthrottle now to avoid the tick | |
4555 | * trying to unthrottle while we already re-started the event. | |
4556 | */ | |
4557 | if (event->hw.interrupts == MAX_INTERRUPTS) { | |
4558 | event->hw.interrupts = 0; | |
4559 | perf_log_throttle(event, 1); | |
4560 | } | |
bad7192b PZ |
4561 | event->pmu->stop(event, PERF_EF_UPDATE); |
4562 | } | |
4563 | ||
4564 | local64_set(&event->hw.period_left, 0); | |
4565 | ||
4566 | if (active) { | |
4567 | event->pmu->start(event, PERF_EF_RELOAD); | |
4568 | perf_pmu_enable(ctx->pmu); | |
4569 | } | |
c7999c6f PZ |
4570 | } |
4571 | ||
4572 | static int perf_event_period(struct perf_event *event, u64 __user *arg) | |
4573 | { | |
c7999c6f PZ |
4574 | u64 value; |
4575 | ||
4576 | if (!is_sampling_event(event)) | |
4577 | return -EINVAL; | |
4578 | ||
4579 | if (copy_from_user(&value, arg, sizeof(value))) | |
4580 | return -EFAULT; | |
4581 | ||
4582 | if (!value) | |
4583 | return -EINVAL; | |
4584 | ||
4585 | if (event->attr.freq && value > sysctl_perf_event_sample_rate) | |
4586 | return -EINVAL; | |
4587 | ||
fae3fde6 | 4588 | event_function_call(event, __perf_event_period, &value); |
08247e31 | 4589 | |
c7999c6f | 4590 | return 0; |
08247e31 PZ |
4591 | } |
4592 | ||
ac9721f3 PZ |
4593 | static const struct file_operations perf_fops; |
4594 | ||
2903ff01 | 4595 | static inline int perf_fget_light(int fd, struct fd *p) |
ac9721f3 | 4596 | { |
2903ff01 AV |
4597 | struct fd f = fdget(fd); |
4598 | if (!f.file) | |
4599 | return -EBADF; | |
ac9721f3 | 4600 | |
2903ff01 AV |
4601 | if (f.file->f_op != &perf_fops) { |
4602 | fdput(f); | |
4603 | return -EBADF; | |
ac9721f3 | 4604 | } |
2903ff01 AV |
4605 | *p = f; |
4606 | return 0; | |
ac9721f3 PZ |
4607 | } |
4608 | ||
4609 | static int perf_event_set_output(struct perf_event *event, | |
4610 | struct perf_event *output_event); | |
6fb2915d | 4611 | static int perf_event_set_filter(struct perf_event *event, void __user *arg); |
2541517c | 4612 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd); |
a4be7c27 | 4613 | |
f63a8daa | 4614 | static long _perf_ioctl(struct perf_event *event, unsigned int cmd, unsigned long arg) |
d859e29f | 4615 | { |
cdd6c482 | 4616 | void (*func)(struct perf_event *); |
3df5edad | 4617 | u32 flags = arg; |
d859e29f PM |
4618 | |
4619 | switch (cmd) { | |
cdd6c482 | 4620 | case PERF_EVENT_IOC_ENABLE: |
f63a8daa | 4621 | func = _perf_event_enable; |
d859e29f | 4622 | break; |
cdd6c482 | 4623 | case PERF_EVENT_IOC_DISABLE: |
f63a8daa | 4624 | func = _perf_event_disable; |
79f14641 | 4625 | break; |
cdd6c482 | 4626 | case PERF_EVENT_IOC_RESET: |
f63a8daa | 4627 | func = _perf_event_reset; |
6de6a7b9 | 4628 | break; |
3df5edad | 4629 | |
cdd6c482 | 4630 | case PERF_EVENT_IOC_REFRESH: |
f63a8daa | 4631 | return _perf_event_refresh(event, arg); |
08247e31 | 4632 | |
cdd6c482 IM |
4633 | case PERF_EVENT_IOC_PERIOD: |
4634 | return perf_event_period(event, (u64 __user *)arg); | |
08247e31 | 4635 | |
cf4957f1 JO |
4636 | case PERF_EVENT_IOC_ID: |
4637 | { | |
4638 | u64 id = primary_event_id(event); | |
4639 | ||
4640 | if (copy_to_user((void __user *)arg, &id, sizeof(id))) | |
4641 | return -EFAULT; | |
4642 | return 0; | |
4643 | } | |
4644 | ||
cdd6c482 | 4645 | case PERF_EVENT_IOC_SET_OUTPUT: |
ac9721f3 | 4646 | { |
ac9721f3 | 4647 | int ret; |
ac9721f3 | 4648 | if (arg != -1) { |
2903ff01 AV |
4649 | struct perf_event *output_event; |
4650 | struct fd output; | |
4651 | ret = perf_fget_light(arg, &output); | |
4652 | if (ret) | |
4653 | return ret; | |
4654 | output_event = output.file->private_data; | |
4655 | ret = perf_event_set_output(event, output_event); | |
4656 | fdput(output); | |
4657 | } else { | |
4658 | ret = perf_event_set_output(event, NULL); | |
ac9721f3 | 4659 | } |
ac9721f3 PZ |
4660 | return ret; |
4661 | } | |
a4be7c27 | 4662 | |
6fb2915d LZ |
4663 | case PERF_EVENT_IOC_SET_FILTER: |
4664 | return perf_event_set_filter(event, (void __user *)arg); | |
4665 | ||
2541517c AS |
4666 | case PERF_EVENT_IOC_SET_BPF: |
4667 | return perf_event_set_bpf_prog(event, arg); | |
4668 | ||
86e7972f WN |
4669 | case PERF_EVENT_IOC_PAUSE_OUTPUT: { |
4670 | struct ring_buffer *rb; | |
4671 | ||
4672 | rcu_read_lock(); | |
4673 | rb = rcu_dereference(event->rb); | |
4674 | if (!rb || !rb->nr_pages) { | |
4675 | rcu_read_unlock(); | |
4676 | return -EINVAL; | |
4677 | } | |
4678 | rb_toggle_paused(rb, !!arg); | |
4679 | rcu_read_unlock(); | |
4680 | return 0; | |
4681 | } | |
d859e29f | 4682 | default: |
3df5edad | 4683 | return -ENOTTY; |
d859e29f | 4684 | } |
3df5edad PZ |
4685 | |
4686 | if (flags & PERF_IOC_FLAG_GROUP) | |
cdd6c482 | 4687 | perf_event_for_each(event, func); |
3df5edad | 4688 | else |
cdd6c482 | 4689 | perf_event_for_each_child(event, func); |
3df5edad PZ |
4690 | |
4691 | return 0; | |
d859e29f PM |
4692 | } |
4693 | ||
f63a8daa PZ |
4694 | static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
4695 | { | |
4696 | struct perf_event *event = file->private_data; | |
4697 | struct perf_event_context *ctx; | |
4698 | long ret; | |
4699 | ||
4700 | ctx = perf_event_ctx_lock(event); | |
4701 | ret = _perf_ioctl(event, cmd, arg); | |
4702 | perf_event_ctx_unlock(event, ctx); | |
4703 | ||
4704 | return ret; | |
4705 | } | |
4706 | ||
b3f20785 PM |
4707 | #ifdef CONFIG_COMPAT |
4708 | static long perf_compat_ioctl(struct file *file, unsigned int cmd, | |
4709 | unsigned long arg) | |
4710 | { | |
4711 | switch (_IOC_NR(cmd)) { | |
4712 | case _IOC_NR(PERF_EVENT_IOC_SET_FILTER): | |
4713 | case _IOC_NR(PERF_EVENT_IOC_ID): | |
4714 | /* Fix up pointer size (usually 4 -> 8 in 32-on-64-bit case */ | |
4715 | if (_IOC_SIZE(cmd) == sizeof(compat_uptr_t)) { | |
4716 | cmd &= ~IOCSIZE_MASK; | |
4717 | cmd |= sizeof(void *) << IOCSIZE_SHIFT; | |
4718 | } | |
4719 | break; | |
4720 | } | |
4721 | return perf_ioctl(file, cmd, arg); | |
4722 | } | |
4723 | #else | |
4724 | # define perf_compat_ioctl NULL | |
4725 | #endif | |
4726 | ||
cdd6c482 | 4727 | int perf_event_task_enable(void) |
771d7cde | 4728 | { |
f63a8daa | 4729 | struct perf_event_context *ctx; |
cdd6c482 | 4730 | struct perf_event *event; |
771d7cde | 4731 | |
cdd6c482 | 4732 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
4733 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
4734 | ctx = perf_event_ctx_lock(event); | |
4735 | perf_event_for_each_child(event, _perf_event_enable); | |
4736 | perf_event_ctx_unlock(event, ctx); | |
4737 | } | |
cdd6c482 | 4738 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
4739 | |
4740 | return 0; | |
4741 | } | |
4742 | ||
cdd6c482 | 4743 | int perf_event_task_disable(void) |
771d7cde | 4744 | { |
f63a8daa | 4745 | struct perf_event_context *ctx; |
cdd6c482 | 4746 | struct perf_event *event; |
771d7cde | 4747 | |
cdd6c482 | 4748 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
4749 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
4750 | ctx = perf_event_ctx_lock(event); | |
4751 | perf_event_for_each_child(event, _perf_event_disable); | |
4752 | perf_event_ctx_unlock(event, ctx); | |
4753 | } | |
cdd6c482 | 4754 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
4755 | |
4756 | return 0; | |
4757 | } | |
4758 | ||
cdd6c482 | 4759 | static int perf_event_index(struct perf_event *event) |
194002b2 | 4760 | { |
a4eaf7f1 PZ |
4761 | if (event->hw.state & PERF_HES_STOPPED) |
4762 | return 0; | |
4763 | ||
cdd6c482 | 4764 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
194002b2 PZ |
4765 | return 0; |
4766 | ||
35edc2a5 | 4767 | return event->pmu->event_idx(event); |
194002b2 PZ |
4768 | } |
4769 | ||
c4794295 | 4770 | static void calc_timer_values(struct perf_event *event, |
e3f3541c | 4771 | u64 *now, |
7f310a5d EM |
4772 | u64 *enabled, |
4773 | u64 *running) | |
c4794295 | 4774 | { |
e3f3541c | 4775 | u64 ctx_time; |
c4794295 | 4776 | |
e3f3541c PZ |
4777 | *now = perf_clock(); |
4778 | ctx_time = event->shadow_ctx_time + *now; | |
c4794295 EM |
4779 | *enabled = ctx_time - event->tstamp_enabled; |
4780 | *running = ctx_time - event->tstamp_running; | |
4781 | } | |
4782 | ||
fa731587 PZ |
4783 | static void perf_event_init_userpage(struct perf_event *event) |
4784 | { | |
4785 | struct perf_event_mmap_page *userpg; | |
4786 | struct ring_buffer *rb; | |
4787 | ||
4788 | rcu_read_lock(); | |
4789 | rb = rcu_dereference(event->rb); | |
4790 | if (!rb) | |
4791 | goto unlock; | |
4792 | ||
4793 | userpg = rb->user_page; | |
4794 | ||
4795 | /* Allow new userspace to detect that bit 0 is deprecated */ | |
4796 | userpg->cap_bit0_is_deprecated = 1; | |
4797 | userpg->size = offsetof(struct perf_event_mmap_page, __reserved); | |
e8c6deac AS |
4798 | userpg->data_offset = PAGE_SIZE; |
4799 | userpg->data_size = perf_data_size(rb); | |
fa731587 PZ |
4800 | |
4801 | unlock: | |
4802 | rcu_read_unlock(); | |
4803 | } | |
4804 | ||
c1317ec2 AL |
4805 | void __weak arch_perf_update_userpage( |
4806 | struct perf_event *event, struct perf_event_mmap_page *userpg, u64 now) | |
e3f3541c PZ |
4807 | { |
4808 | } | |
4809 | ||
38ff667b PZ |
4810 | /* |
4811 | * Callers need to ensure there can be no nesting of this function, otherwise | |
4812 | * the seqlock logic goes bad. We can not serialize this because the arch | |
4813 | * code calls this from NMI context. | |
4814 | */ | |
cdd6c482 | 4815 | void perf_event_update_userpage(struct perf_event *event) |
37d81828 | 4816 | { |
cdd6c482 | 4817 | struct perf_event_mmap_page *userpg; |
76369139 | 4818 | struct ring_buffer *rb; |
e3f3541c | 4819 | u64 enabled, running, now; |
38ff667b PZ |
4820 | |
4821 | rcu_read_lock(); | |
5ec4c599 PZ |
4822 | rb = rcu_dereference(event->rb); |
4823 | if (!rb) | |
4824 | goto unlock; | |
4825 | ||
0d641208 EM |
4826 | /* |
4827 | * compute total_time_enabled, total_time_running | |
4828 | * based on snapshot values taken when the event | |
4829 | * was last scheduled in. | |
4830 | * | |
4831 | * we cannot simply called update_context_time() | |
4832 | * because of locking issue as we can be called in | |
4833 | * NMI context | |
4834 | */ | |
e3f3541c | 4835 | calc_timer_values(event, &now, &enabled, &running); |
38ff667b | 4836 | |
76369139 | 4837 | userpg = rb->user_page; |
7b732a75 PZ |
4838 | /* |
4839 | * Disable preemption so as to not let the corresponding user-space | |
4840 | * spin too long if we get preempted. | |
4841 | */ | |
4842 | preempt_disable(); | |
37d81828 | 4843 | ++userpg->lock; |
92f22a38 | 4844 | barrier(); |
cdd6c482 | 4845 | userpg->index = perf_event_index(event); |
b5e58793 | 4846 | userpg->offset = perf_event_count(event); |
365a4038 | 4847 | if (userpg->index) |
e7850595 | 4848 | userpg->offset -= local64_read(&event->hw.prev_count); |
7b732a75 | 4849 | |
0d641208 | 4850 | userpg->time_enabled = enabled + |
cdd6c482 | 4851 | atomic64_read(&event->child_total_time_enabled); |
7f8b4e4e | 4852 | |
0d641208 | 4853 | userpg->time_running = running + |
cdd6c482 | 4854 | atomic64_read(&event->child_total_time_running); |
7f8b4e4e | 4855 | |
c1317ec2 | 4856 | arch_perf_update_userpage(event, userpg, now); |
e3f3541c | 4857 | |
92f22a38 | 4858 | barrier(); |
37d81828 | 4859 | ++userpg->lock; |
7b732a75 | 4860 | preempt_enable(); |
38ff667b | 4861 | unlock: |
7b732a75 | 4862 | rcu_read_unlock(); |
37d81828 PM |
4863 | } |
4864 | ||
906010b2 PZ |
4865 | static int perf_mmap_fault(struct vm_area_struct *vma, struct vm_fault *vmf) |
4866 | { | |
4867 | struct perf_event *event = vma->vm_file->private_data; | |
76369139 | 4868 | struct ring_buffer *rb; |
906010b2 PZ |
4869 | int ret = VM_FAULT_SIGBUS; |
4870 | ||
4871 | if (vmf->flags & FAULT_FLAG_MKWRITE) { | |
4872 | if (vmf->pgoff == 0) | |
4873 | ret = 0; | |
4874 | return ret; | |
4875 | } | |
4876 | ||
4877 | rcu_read_lock(); | |
76369139 FW |
4878 | rb = rcu_dereference(event->rb); |
4879 | if (!rb) | |
906010b2 PZ |
4880 | goto unlock; |
4881 | ||
4882 | if (vmf->pgoff && (vmf->flags & FAULT_FLAG_WRITE)) | |
4883 | goto unlock; | |
4884 | ||
76369139 | 4885 | vmf->page = perf_mmap_to_page(rb, vmf->pgoff); |
906010b2 PZ |
4886 | if (!vmf->page) |
4887 | goto unlock; | |
4888 | ||
4889 | get_page(vmf->page); | |
4890 | vmf->page->mapping = vma->vm_file->f_mapping; | |
4891 | vmf->page->index = vmf->pgoff; | |
4892 | ||
4893 | ret = 0; | |
4894 | unlock: | |
4895 | rcu_read_unlock(); | |
4896 | ||
4897 | return ret; | |
4898 | } | |
4899 | ||
10c6db11 PZ |
4900 | static void ring_buffer_attach(struct perf_event *event, |
4901 | struct ring_buffer *rb) | |
4902 | { | |
b69cf536 | 4903 | struct ring_buffer *old_rb = NULL; |
10c6db11 PZ |
4904 | unsigned long flags; |
4905 | ||
b69cf536 PZ |
4906 | if (event->rb) { |
4907 | /* | |
4908 | * Should be impossible, we set this when removing | |
4909 | * event->rb_entry and wait/clear when adding event->rb_entry. | |
4910 | */ | |
4911 | WARN_ON_ONCE(event->rcu_pending); | |
10c6db11 | 4912 | |
b69cf536 | 4913 | old_rb = event->rb; |
b69cf536 PZ |
4914 | spin_lock_irqsave(&old_rb->event_lock, flags); |
4915 | list_del_rcu(&event->rb_entry); | |
4916 | spin_unlock_irqrestore(&old_rb->event_lock, flags); | |
10c6db11 | 4917 | |
2f993cf0 ON |
4918 | event->rcu_batches = get_state_synchronize_rcu(); |
4919 | event->rcu_pending = 1; | |
b69cf536 | 4920 | } |
10c6db11 | 4921 | |
b69cf536 | 4922 | if (rb) { |
2f993cf0 ON |
4923 | if (event->rcu_pending) { |
4924 | cond_synchronize_rcu(event->rcu_batches); | |
4925 | event->rcu_pending = 0; | |
4926 | } | |
4927 | ||
b69cf536 PZ |
4928 | spin_lock_irqsave(&rb->event_lock, flags); |
4929 | list_add_rcu(&event->rb_entry, &rb->event_list); | |
4930 | spin_unlock_irqrestore(&rb->event_lock, flags); | |
4931 | } | |
4932 | ||
767ae086 AS |
4933 | /* |
4934 | * Avoid racing with perf_mmap_close(AUX): stop the event | |
4935 | * before swizzling the event::rb pointer; if it's getting | |
4936 | * unmapped, its aux_mmap_count will be 0 and it won't | |
4937 | * restart. See the comment in __perf_pmu_output_stop(). | |
4938 | * | |
4939 | * Data will inevitably be lost when set_output is done in | |
4940 | * mid-air, but then again, whoever does it like this is | |
4941 | * not in for the data anyway. | |
4942 | */ | |
4943 | if (has_aux(event)) | |
4944 | perf_event_stop(event, 0); | |
4945 | ||
b69cf536 PZ |
4946 | rcu_assign_pointer(event->rb, rb); |
4947 | ||
4948 | if (old_rb) { | |
4949 | ring_buffer_put(old_rb); | |
4950 | /* | |
4951 | * Since we detached before setting the new rb, so that we | |
4952 | * could attach the new rb, we could have missed a wakeup. | |
4953 | * Provide it now. | |
4954 | */ | |
4955 | wake_up_all(&event->waitq); | |
4956 | } | |
10c6db11 PZ |
4957 | } |
4958 | ||
4959 | static void ring_buffer_wakeup(struct perf_event *event) | |
4960 | { | |
4961 | struct ring_buffer *rb; | |
4962 | ||
4963 | rcu_read_lock(); | |
4964 | rb = rcu_dereference(event->rb); | |
9bb5d40c PZ |
4965 | if (rb) { |
4966 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) | |
4967 | wake_up_all(&event->waitq); | |
4968 | } | |
10c6db11 PZ |
4969 | rcu_read_unlock(); |
4970 | } | |
4971 | ||
fdc26706 | 4972 | struct ring_buffer *ring_buffer_get(struct perf_event *event) |
7b732a75 | 4973 | { |
76369139 | 4974 | struct ring_buffer *rb; |
7b732a75 | 4975 | |
ac9721f3 | 4976 | rcu_read_lock(); |
76369139 FW |
4977 | rb = rcu_dereference(event->rb); |
4978 | if (rb) { | |
4979 | if (!atomic_inc_not_zero(&rb->refcount)) | |
4980 | rb = NULL; | |
ac9721f3 PZ |
4981 | } |
4982 | rcu_read_unlock(); | |
4983 | ||
76369139 | 4984 | return rb; |
ac9721f3 PZ |
4985 | } |
4986 | ||
fdc26706 | 4987 | void ring_buffer_put(struct ring_buffer *rb) |
ac9721f3 | 4988 | { |
76369139 | 4989 | if (!atomic_dec_and_test(&rb->refcount)) |
ac9721f3 | 4990 | return; |
7b732a75 | 4991 | |
9bb5d40c | 4992 | WARN_ON_ONCE(!list_empty(&rb->event_list)); |
10c6db11 | 4993 | |
76369139 | 4994 | call_rcu(&rb->rcu_head, rb_free_rcu); |
7b732a75 PZ |
4995 | } |
4996 | ||
4997 | static void perf_mmap_open(struct vm_area_struct *vma) | |
4998 | { | |
cdd6c482 | 4999 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 5000 | |
cdd6c482 | 5001 | atomic_inc(&event->mmap_count); |
9bb5d40c | 5002 | atomic_inc(&event->rb->mmap_count); |
1e0fb9ec | 5003 | |
45bfb2e5 PZ |
5004 | if (vma->vm_pgoff) |
5005 | atomic_inc(&event->rb->aux_mmap_count); | |
5006 | ||
1e0fb9ec AL |
5007 | if (event->pmu->event_mapped) |
5008 | event->pmu->event_mapped(event); | |
7b732a75 PZ |
5009 | } |
5010 | ||
95ff4ca2 AS |
5011 | static void perf_pmu_output_stop(struct perf_event *event); |
5012 | ||
9bb5d40c PZ |
5013 | /* |
5014 | * A buffer can be mmap()ed multiple times; either directly through the same | |
5015 | * event, or through other events by use of perf_event_set_output(). | |
5016 | * | |
5017 | * In order to undo the VM accounting done by perf_mmap() we need to destroy | |
5018 | * the buffer here, where we still have a VM context. This means we need | |
5019 | * to detach all events redirecting to us. | |
5020 | */ | |
7b732a75 PZ |
5021 | static void perf_mmap_close(struct vm_area_struct *vma) |
5022 | { | |
cdd6c482 | 5023 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 5024 | |
b69cf536 | 5025 | struct ring_buffer *rb = ring_buffer_get(event); |
9bb5d40c PZ |
5026 | struct user_struct *mmap_user = rb->mmap_user; |
5027 | int mmap_locked = rb->mmap_locked; | |
5028 | unsigned long size = perf_data_size(rb); | |
789f90fc | 5029 | |
1e0fb9ec AL |
5030 | if (event->pmu->event_unmapped) |
5031 | event->pmu->event_unmapped(event); | |
5032 | ||
45bfb2e5 PZ |
5033 | /* |
5034 | * rb->aux_mmap_count will always drop before rb->mmap_count and | |
5035 | * event->mmap_count, so it is ok to use event->mmap_mutex to | |
5036 | * serialize with perf_mmap here. | |
5037 | */ | |
5038 | if (rb_has_aux(rb) && vma->vm_pgoff == rb->aux_pgoff && | |
5039 | atomic_dec_and_mutex_lock(&rb->aux_mmap_count, &event->mmap_mutex)) { | |
95ff4ca2 AS |
5040 | /* |
5041 | * Stop all AUX events that are writing to this buffer, | |
5042 | * so that we can free its AUX pages and corresponding PMU | |
5043 | * data. Note that after rb::aux_mmap_count dropped to zero, | |
5044 | * they won't start any more (see perf_aux_output_begin()). | |
5045 | */ | |
5046 | perf_pmu_output_stop(event); | |
5047 | ||
5048 | /* now it's safe to free the pages */ | |
45bfb2e5 PZ |
5049 | atomic_long_sub(rb->aux_nr_pages, &mmap_user->locked_vm); |
5050 | vma->vm_mm->pinned_vm -= rb->aux_mmap_locked; | |
5051 | ||
95ff4ca2 | 5052 | /* this has to be the last one */ |
45bfb2e5 | 5053 | rb_free_aux(rb); |
95ff4ca2 AS |
5054 | WARN_ON_ONCE(atomic_read(&rb->aux_refcount)); |
5055 | ||
45bfb2e5 PZ |
5056 | mutex_unlock(&event->mmap_mutex); |
5057 | } | |
5058 | ||
9bb5d40c PZ |
5059 | atomic_dec(&rb->mmap_count); |
5060 | ||
5061 | if (!atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex)) | |
b69cf536 | 5062 | goto out_put; |
9bb5d40c | 5063 | |
b69cf536 | 5064 | ring_buffer_attach(event, NULL); |
9bb5d40c PZ |
5065 | mutex_unlock(&event->mmap_mutex); |
5066 | ||
5067 | /* If there's still other mmap()s of this buffer, we're done. */ | |
b69cf536 PZ |
5068 | if (atomic_read(&rb->mmap_count)) |
5069 | goto out_put; | |
ac9721f3 | 5070 | |
9bb5d40c PZ |
5071 | /* |
5072 | * No other mmap()s, detach from all other events that might redirect | |
5073 | * into the now unreachable buffer. Somewhat complicated by the | |
5074 | * fact that rb::event_lock otherwise nests inside mmap_mutex. | |
5075 | */ | |
5076 | again: | |
5077 | rcu_read_lock(); | |
5078 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) { | |
5079 | if (!atomic_long_inc_not_zero(&event->refcount)) { | |
5080 | /* | |
5081 | * This event is en-route to free_event() which will | |
5082 | * detach it and remove it from the list. | |
5083 | */ | |
5084 | continue; | |
5085 | } | |
5086 | rcu_read_unlock(); | |
789f90fc | 5087 | |
9bb5d40c PZ |
5088 | mutex_lock(&event->mmap_mutex); |
5089 | /* | |
5090 | * Check we didn't race with perf_event_set_output() which can | |
5091 | * swizzle the rb from under us while we were waiting to | |
5092 | * acquire mmap_mutex. | |
5093 | * | |
5094 | * If we find a different rb; ignore this event, a next | |
5095 | * iteration will no longer find it on the list. We have to | |
5096 | * still restart the iteration to make sure we're not now | |
5097 | * iterating the wrong list. | |
5098 | */ | |
b69cf536 PZ |
5099 | if (event->rb == rb) |
5100 | ring_buffer_attach(event, NULL); | |
5101 | ||
cdd6c482 | 5102 | mutex_unlock(&event->mmap_mutex); |
9bb5d40c | 5103 | put_event(event); |
ac9721f3 | 5104 | |
9bb5d40c PZ |
5105 | /* |
5106 | * Restart the iteration; either we're on the wrong list or | |
5107 | * destroyed its integrity by doing a deletion. | |
5108 | */ | |
5109 | goto again; | |
7b732a75 | 5110 | } |
9bb5d40c PZ |
5111 | rcu_read_unlock(); |
5112 | ||
5113 | /* | |
5114 | * It could be there's still a few 0-ref events on the list; they'll | |
5115 | * get cleaned up by free_event() -- they'll also still have their | |
5116 | * ref on the rb and will free it whenever they are done with it. | |
5117 | * | |
5118 | * Aside from that, this buffer is 'fully' detached and unmapped, | |
5119 | * undo the VM accounting. | |
5120 | */ | |
5121 | ||
5122 | atomic_long_sub((size >> PAGE_SHIFT) + 1, &mmap_user->locked_vm); | |
5123 | vma->vm_mm->pinned_vm -= mmap_locked; | |
5124 | free_uid(mmap_user); | |
5125 | ||
b69cf536 | 5126 | out_put: |
9bb5d40c | 5127 | ring_buffer_put(rb); /* could be last */ |
37d81828 PM |
5128 | } |
5129 | ||
f0f37e2f | 5130 | static const struct vm_operations_struct perf_mmap_vmops = { |
43a21ea8 | 5131 | .open = perf_mmap_open, |
45bfb2e5 | 5132 | .close = perf_mmap_close, /* non mergable */ |
43a21ea8 PZ |
5133 | .fault = perf_mmap_fault, |
5134 | .page_mkwrite = perf_mmap_fault, | |
37d81828 PM |
5135 | }; |
5136 | ||
5137 | static int perf_mmap(struct file *file, struct vm_area_struct *vma) | |
5138 | { | |
cdd6c482 | 5139 | struct perf_event *event = file->private_data; |
22a4f650 | 5140 | unsigned long user_locked, user_lock_limit; |
789f90fc | 5141 | struct user_struct *user = current_user(); |
22a4f650 | 5142 | unsigned long locked, lock_limit; |
45bfb2e5 | 5143 | struct ring_buffer *rb = NULL; |
7b732a75 PZ |
5144 | unsigned long vma_size; |
5145 | unsigned long nr_pages; | |
45bfb2e5 | 5146 | long user_extra = 0, extra = 0; |
d57e34fd | 5147 | int ret = 0, flags = 0; |
37d81828 | 5148 | |
c7920614 PZ |
5149 | /* |
5150 | * Don't allow mmap() of inherited per-task counters. This would | |
5151 | * create a performance issue due to all children writing to the | |
76369139 | 5152 | * same rb. |
c7920614 PZ |
5153 | */ |
5154 | if (event->cpu == -1 && event->attr.inherit) | |
5155 | return -EINVAL; | |
5156 | ||
43a21ea8 | 5157 | if (!(vma->vm_flags & VM_SHARED)) |
37d81828 | 5158 | return -EINVAL; |
7b732a75 PZ |
5159 | |
5160 | vma_size = vma->vm_end - vma->vm_start; | |
45bfb2e5 PZ |
5161 | |
5162 | if (vma->vm_pgoff == 0) { | |
5163 | nr_pages = (vma_size / PAGE_SIZE) - 1; | |
5164 | } else { | |
5165 | /* | |
5166 | * AUX area mapping: if rb->aux_nr_pages != 0, it's already | |
5167 | * mapped, all subsequent mappings should have the same size | |
5168 | * and offset. Must be above the normal perf buffer. | |
5169 | */ | |
5170 | u64 aux_offset, aux_size; | |
5171 | ||
5172 | if (!event->rb) | |
5173 | return -EINVAL; | |
5174 | ||
5175 | nr_pages = vma_size / PAGE_SIZE; | |
5176 | ||
5177 | mutex_lock(&event->mmap_mutex); | |
5178 | ret = -EINVAL; | |
5179 | ||
5180 | rb = event->rb; | |
5181 | if (!rb) | |
5182 | goto aux_unlock; | |
5183 | ||
5184 | aux_offset = ACCESS_ONCE(rb->user_page->aux_offset); | |
5185 | aux_size = ACCESS_ONCE(rb->user_page->aux_size); | |
5186 | ||
5187 | if (aux_offset < perf_data_size(rb) + PAGE_SIZE) | |
5188 | goto aux_unlock; | |
5189 | ||
5190 | if (aux_offset != vma->vm_pgoff << PAGE_SHIFT) | |
5191 | goto aux_unlock; | |
5192 | ||
5193 | /* already mapped with a different offset */ | |
5194 | if (rb_has_aux(rb) && rb->aux_pgoff != vma->vm_pgoff) | |
5195 | goto aux_unlock; | |
5196 | ||
5197 | if (aux_size != vma_size || aux_size != nr_pages * PAGE_SIZE) | |
5198 | goto aux_unlock; | |
5199 | ||
5200 | /* already mapped with a different size */ | |
5201 | if (rb_has_aux(rb) && rb->aux_nr_pages != nr_pages) | |
5202 | goto aux_unlock; | |
5203 | ||
5204 | if (!is_power_of_2(nr_pages)) | |
5205 | goto aux_unlock; | |
5206 | ||
5207 | if (!atomic_inc_not_zero(&rb->mmap_count)) | |
5208 | goto aux_unlock; | |
5209 | ||
5210 | if (rb_has_aux(rb)) { | |
5211 | atomic_inc(&rb->aux_mmap_count); | |
5212 | ret = 0; | |
5213 | goto unlock; | |
5214 | } | |
5215 | ||
5216 | atomic_set(&rb->aux_mmap_count, 1); | |
5217 | user_extra = nr_pages; | |
5218 | ||
5219 | goto accounting; | |
5220 | } | |
7b732a75 | 5221 | |
7730d865 | 5222 | /* |
76369139 | 5223 | * If we have rb pages ensure they're a power-of-two number, so we |
7730d865 PZ |
5224 | * can do bitmasks instead of modulo. |
5225 | */ | |
2ed11312 | 5226 | if (nr_pages != 0 && !is_power_of_2(nr_pages)) |
37d81828 PM |
5227 | return -EINVAL; |
5228 | ||
7b732a75 | 5229 | if (vma_size != PAGE_SIZE * (1 + nr_pages)) |
37d81828 PM |
5230 | return -EINVAL; |
5231 | ||
cdd6c482 | 5232 | WARN_ON_ONCE(event->ctx->parent_ctx); |
9bb5d40c | 5233 | again: |
cdd6c482 | 5234 | mutex_lock(&event->mmap_mutex); |
76369139 | 5235 | if (event->rb) { |
9bb5d40c | 5236 | if (event->rb->nr_pages != nr_pages) { |
ebb3c4c4 | 5237 | ret = -EINVAL; |
9bb5d40c PZ |
5238 | goto unlock; |
5239 | } | |
5240 | ||
5241 | if (!atomic_inc_not_zero(&event->rb->mmap_count)) { | |
5242 | /* | |
5243 | * Raced against perf_mmap_close() through | |
5244 | * perf_event_set_output(). Try again, hope for better | |
5245 | * luck. | |
5246 | */ | |
5247 | mutex_unlock(&event->mmap_mutex); | |
5248 | goto again; | |
5249 | } | |
5250 | ||
ebb3c4c4 PZ |
5251 | goto unlock; |
5252 | } | |
5253 | ||
789f90fc | 5254 | user_extra = nr_pages + 1; |
45bfb2e5 PZ |
5255 | |
5256 | accounting: | |
cdd6c482 | 5257 | user_lock_limit = sysctl_perf_event_mlock >> (PAGE_SHIFT - 10); |
a3862d3f IM |
5258 | |
5259 | /* | |
5260 | * Increase the limit linearly with more CPUs: | |
5261 | */ | |
5262 | user_lock_limit *= num_online_cpus(); | |
5263 | ||
789f90fc | 5264 | user_locked = atomic_long_read(&user->locked_vm) + user_extra; |
c5078f78 | 5265 | |
789f90fc PZ |
5266 | if (user_locked > user_lock_limit) |
5267 | extra = user_locked - user_lock_limit; | |
7b732a75 | 5268 | |
78d7d407 | 5269 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
7b732a75 | 5270 | lock_limit >>= PAGE_SHIFT; |
bc3e53f6 | 5271 | locked = vma->vm_mm->pinned_vm + extra; |
7b732a75 | 5272 | |
459ec28a IM |
5273 | if ((locked > lock_limit) && perf_paranoid_tracepoint_raw() && |
5274 | !capable(CAP_IPC_LOCK)) { | |
ebb3c4c4 PZ |
5275 | ret = -EPERM; |
5276 | goto unlock; | |
5277 | } | |
7b732a75 | 5278 | |
45bfb2e5 | 5279 | WARN_ON(!rb && event->rb); |
906010b2 | 5280 | |
d57e34fd | 5281 | if (vma->vm_flags & VM_WRITE) |
76369139 | 5282 | flags |= RING_BUFFER_WRITABLE; |
d57e34fd | 5283 | |
76369139 | 5284 | if (!rb) { |
45bfb2e5 PZ |
5285 | rb = rb_alloc(nr_pages, |
5286 | event->attr.watermark ? event->attr.wakeup_watermark : 0, | |
5287 | event->cpu, flags); | |
26cb63ad | 5288 | |
45bfb2e5 PZ |
5289 | if (!rb) { |
5290 | ret = -ENOMEM; | |
5291 | goto unlock; | |
5292 | } | |
43a21ea8 | 5293 | |
45bfb2e5 PZ |
5294 | atomic_set(&rb->mmap_count, 1); |
5295 | rb->mmap_user = get_current_user(); | |
5296 | rb->mmap_locked = extra; | |
26cb63ad | 5297 | |
45bfb2e5 | 5298 | ring_buffer_attach(event, rb); |
ac9721f3 | 5299 | |
45bfb2e5 PZ |
5300 | perf_event_init_userpage(event); |
5301 | perf_event_update_userpage(event); | |
5302 | } else { | |
1a594131 AS |
5303 | ret = rb_alloc_aux(rb, event, vma->vm_pgoff, nr_pages, |
5304 | event->attr.aux_watermark, flags); | |
45bfb2e5 PZ |
5305 | if (!ret) |
5306 | rb->aux_mmap_locked = extra; | |
5307 | } | |
9a0f05cb | 5308 | |
ebb3c4c4 | 5309 | unlock: |
45bfb2e5 PZ |
5310 | if (!ret) { |
5311 | atomic_long_add(user_extra, &user->locked_vm); | |
5312 | vma->vm_mm->pinned_vm += extra; | |
5313 | ||
ac9721f3 | 5314 | atomic_inc(&event->mmap_count); |
45bfb2e5 PZ |
5315 | } else if (rb) { |
5316 | atomic_dec(&rb->mmap_count); | |
5317 | } | |
5318 | aux_unlock: | |
cdd6c482 | 5319 | mutex_unlock(&event->mmap_mutex); |
37d81828 | 5320 | |
9bb5d40c PZ |
5321 | /* |
5322 | * Since pinned accounting is per vm we cannot allow fork() to copy our | |
5323 | * vma. | |
5324 | */ | |
26cb63ad | 5325 | vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND | VM_DONTDUMP; |
37d81828 | 5326 | vma->vm_ops = &perf_mmap_vmops; |
7b732a75 | 5327 | |
1e0fb9ec AL |
5328 | if (event->pmu->event_mapped) |
5329 | event->pmu->event_mapped(event); | |
5330 | ||
7b732a75 | 5331 | return ret; |
37d81828 PM |
5332 | } |
5333 | ||
3c446b3d PZ |
5334 | static int perf_fasync(int fd, struct file *filp, int on) |
5335 | { | |
496ad9aa | 5336 | struct inode *inode = file_inode(filp); |
cdd6c482 | 5337 | struct perf_event *event = filp->private_data; |
3c446b3d PZ |
5338 | int retval; |
5339 | ||
5955102c | 5340 | inode_lock(inode); |
cdd6c482 | 5341 | retval = fasync_helper(fd, filp, on, &event->fasync); |
5955102c | 5342 | inode_unlock(inode); |
3c446b3d PZ |
5343 | |
5344 | if (retval < 0) | |
5345 | return retval; | |
5346 | ||
5347 | return 0; | |
5348 | } | |
5349 | ||
0793a61d | 5350 | static const struct file_operations perf_fops = { |
3326c1ce | 5351 | .llseek = no_llseek, |
0793a61d TG |
5352 | .release = perf_release, |
5353 | .read = perf_read, | |
5354 | .poll = perf_poll, | |
d859e29f | 5355 | .unlocked_ioctl = perf_ioctl, |
b3f20785 | 5356 | .compat_ioctl = perf_compat_ioctl, |
37d81828 | 5357 | .mmap = perf_mmap, |
3c446b3d | 5358 | .fasync = perf_fasync, |
0793a61d TG |
5359 | }; |
5360 | ||
925d519a | 5361 | /* |
cdd6c482 | 5362 | * Perf event wakeup |
925d519a PZ |
5363 | * |
5364 | * If there's data, ensure we set the poll() state and publish everything | |
5365 | * to user-space before waking everybody up. | |
5366 | */ | |
5367 | ||
fed66e2c PZ |
5368 | static inline struct fasync_struct **perf_event_fasync(struct perf_event *event) |
5369 | { | |
5370 | /* only the parent has fasync state */ | |
5371 | if (event->parent) | |
5372 | event = event->parent; | |
5373 | return &event->fasync; | |
5374 | } | |
5375 | ||
cdd6c482 | 5376 | void perf_event_wakeup(struct perf_event *event) |
925d519a | 5377 | { |
10c6db11 | 5378 | ring_buffer_wakeup(event); |
4c9e2542 | 5379 | |
cdd6c482 | 5380 | if (event->pending_kill) { |
fed66e2c | 5381 | kill_fasync(perf_event_fasync(event), SIGIO, event->pending_kill); |
cdd6c482 | 5382 | event->pending_kill = 0; |
4c9e2542 | 5383 | } |
925d519a PZ |
5384 | } |
5385 | ||
e360adbe | 5386 | static void perf_pending_event(struct irq_work *entry) |
79f14641 | 5387 | { |
cdd6c482 IM |
5388 | struct perf_event *event = container_of(entry, |
5389 | struct perf_event, pending); | |
d525211f PZ |
5390 | int rctx; |
5391 | ||
5392 | rctx = perf_swevent_get_recursion_context(); | |
5393 | /* | |
5394 | * If we 'fail' here, that's OK, it means recursion is already disabled | |
5395 | * and we won't recurse 'further'. | |
5396 | */ | |
79f14641 | 5397 | |
cdd6c482 IM |
5398 | if (event->pending_disable) { |
5399 | event->pending_disable = 0; | |
fae3fde6 | 5400 | perf_event_disable_local(event); |
79f14641 PZ |
5401 | } |
5402 | ||
cdd6c482 IM |
5403 | if (event->pending_wakeup) { |
5404 | event->pending_wakeup = 0; | |
5405 | perf_event_wakeup(event); | |
79f14641 | 5406 | } |
d525211f PZ |
5407 | |
5408 | if (rctx >= 0) | |
5409 | perf_swevent_put_recursion_context(rctx); | |
79f14641 PZ |
5410 | } |
5411 | ||
39447b38 ZY |
5412 | /* |
5413 | * We assume there is only KVM supporting the callbacks. | |
5414 | * Later on, we might change it to a list if there is | |
5415 | * another virtualization implementation supporting the callbacks. | |
5416 | */ | |
5417 | struct perf_guest_info_callbacks *perf_guest_cbs; | |
5418 | ||
5419 | int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
5420 | { | |
5421 | perf_guest_cbs = cbs; | |
5422 | return 0; | |
5423 | } | |
5424 | EXPORT_SYMBOL_GPL(perf_register_guest_info_callbacks); | |
5425 | ||
5426 | int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
5427 | { | |
5428 | perf_guest_cbs = NULL; | |
5429 | return 0; | |
5430 | } | |
5431 | EXPORT_SYMBOL_GPL(perf_unregister_guest_info_callbacks); | |
5432 | ||
4018994f JO |
5433 | static void |
5434 | perf_output_sample_regs(struct perf_output_handle *handle, | |
5435 | struct pt_regs *regs, u64 mask) | |
5436 | { | |
5437 | int bit; | |
29dd3288 | 5438 | DECLARE_BITMAP(_mask, 64); |
4018994f | 5439 | |
29dd3288 MS |
5440 | bitmap_from_u64(_mask, mask); |
5441 | for_each_set_bit(bit, _mask, sizeof(mask) * BITS_PER_BYTE) { | |
4018994f JO |
5442 | u64 val; |
5443 | ||
5444 | val = perf_reg_value(regs, bit); | |
5445 | perf_output_put(handle, val); | |
5446 | } | |
5447 | } | |
5448 | ||
60e2364e | 5449 | static void perf_sample_regs_user(struct perf_regs *regs_user, |
88a7c26a AL |
5450 | struct pt_regs *regs, |
5451 | struct pt_regs *regs_user_copy) | |
4018994f | 5452 | { |
88a7c26a AL |
5453 | if (user_mode(regs)) { |
5454 | regs_user->abi = perf_reg_abi(current); | |
2565711f | 5455 | regs_user->regs = regs; |
88a7c26a AL |
5456 | } else if (current->mm) { |
5457 | perf_get_regs_user(regs_user, regs, regs_user_copy); | |
2565711f PZ |
5458 | } else { |
5459 | regs_user->abi = PERF_SAMPLE_REGS_ABI_NONE; | |
5460 | regs_user->regs = NULL; | |
4018994f JO |
5461 | } |
5462 | } | |
5463 | ||
60e2364e SE |
5464 | static void perf_sample_regs_intr(struct perf_regs *regs_intr, |
5465 | struct pt_regs *regs) | |
5466 | { | |
5467 | regs_intr->regs = regs; | |
5468 | regs_intr->abi = perf_reg_abi(current); | |
5469 | } | |
5470 | ||
5471 | ||
c5ebcedb JO |
5472 | /* |
5473 | * Get remaining task size from user stack pointer. | |
5474 | * | |
5475 | * It'd be better to take stack vma map and limit this more | |
5476 | * precisly, but there's no way to get it safely under interrupt, | |
5477 | * so using TASK_SIZE as limit. | |
5478 | */ | |
5479 | static u64 perf_ustack_task_size(struct pt_regs *regs) | |
5480 | { | |
5481 | unsigned long addr = perf_user_stack_pointer(regs); | |
5482 | ||
5483 | if (!addr || addr >= TASK_SIZE) | |
5484 | return 0; | |
5485 | ||
5486 | return TASK_SIZE - addr; | |
5487 | } | |
5488 | ||
5489 | static u16 | |
5490 | perf_sample_ustack_size(u16 stack_size, u16 header_size, | |
5491 | struct pt_regs *regs) | |
5492 | { | |
5493 | u64 task_size; | |
5494 | ||
5495 | /* No regs, no stack pointer, no dump. */ | |
5496 | if (!regs) | |
5497 | return 0; | |
5498 | ||
5499 | /* | |
5500 | * Check if we fit in with the requested stack size into the: | |
5501 | * - TASK_SIZE | |
5502 | * If we don't, we limit the size to the TASK_SIZE. | |
5503 | * | |
5504 | * - remaining sample size | |
5505 | * If we don't, we customize the stack size to | |
5506 | * fit in to the remaining sample size. | |
5507 | */ | |
5508 | ||
5509 | task_size = min((u64) USHRT_MAX, perf_ustack_task_size(regs)); | |
5510 | stack_size = min(stack_size, (u16) task_size); | |
5511 | ||
5512 | /* Current header size plus static size and dynamic size. */ | |
5513 | header_size += 2 * sizeof(u64); | |
5514 | ||
5515 | /* Do we fit in with the current stack dump size? */ | |
5516 | if ((u16) (header_size + stack_size) < header_size) { | |
5517 | /* | |
5518 | * If we overflow the maximum size for the sample, | |
5519 | * we customize the stack dump size to fit in. | |
5520 | */ | |
5521 | stack_size = USHRT_MAX - header_size - sizeof(u64); | |
5522 | stack_size = round_up(stack_size, sizeof(u64)); | |
5523 | } | |
5524 | ||
5525 | return stack_size; | |
5526 | } | |
5527 | ||
5528 | static void | |
5529 | perf_output_sample_ustack(struct perf_output_handle *handle, u64 dump_size, | |
5530 | struct pt_regs *regs) | |
5531 | { | |
5532 | /* Case of a kernel thread, nothing to dump */ | |
5533 | if (!regs) { | |
5534 | u64 size = 0; | |
5535 | perf_output_put(handle, size); | |
5536 | } else { | |
5537 | unsigned long sp; | |
5538 | unsigned int rem; | |
5539 | u64 dyn_size; | |
5540 | ||
5541 | /* | |
5542 | * We dump: | |
5543 | * static size | |
5544 | * - the size requested by user or the best one we can fit | |
5545 | * in to the sample max size | |
5546 | * data | |
5547 | * - user stack dump data | |
5548 | * dynamic size | |
5549 | * - the actual dumped size | |
5550 | */ | |
5551 | ||
5552 | /* Static size. */ | |
5553 | perf_output_put(handle, dump_size); | |
5554 | ||
5555 | /* Data. */ | |
5556 | sp = perf_user_stack_pointer(regs); | |
5557 | rem = __output_copy_user(handle, (void *) sp, dump_size); | |
5558 | dyn_size = dump_size - rem; | |
5559 | ||
5560 | perf_output_skip(handle, rem); | |
5561 | ||
5562 | /* Dynamic size. */ | |
5563 | perf_output_put(handle, dyn_size); | |
5564 | } | |
5565 | } | |
5566 | ||
c980d109 ACM |
5567 | static void __perf_event_header__init_id(struct perf_event_header *header, |
5568 | struct perf_sample_data *data, | |
5569 | struct perf_event *event) | |
6844c09d ACM |
5570 | { |
5571 | u64 sample_type = event->attr.sample_type; | |
5572 | ||
5573 | data->type = sample_type; | |
5574 | header->size += event->id_header_size; | |
5575 | ||
5576 | if (sample_type & PERF_SAMPLE_TID) { | |
5577 | /* namespace issues */ | |
5578 | data->tid_entry.pid = perf_event_pid(event, current); | |
5579 | data->tid_entry.tid = perf_event_tid(event, current); | |
5580 | } | |
5581 | ||
5582 | if (sample_type & PERF_SAMPLE_TIME) | |
34f43927 | 5583 | data->time = perf_event_clock(event); |
6844c09d | 5584 | |
ff3d527c | 5585 | if (sample_type & (PERF_SAMPLE_ID | PERF_SAMPLE_IDENTIFIER)) |
6844c09d ACM |
5586 | data->id = primary_event_id(event); |
5587 | ||
5588 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
5589 | data->stream_id = event->id; | |
5590 | ||
5591 | if (sample_type & PERF_SAMPLE_CPU) { | |
5592 | data->cpu_entry.cpu = raw_smp_processor_id(); | |
5593 | data->cpu_entry.reserved = 0; | |
5594 | } | |
5595 | } | |
5596 | ||
76369139 FW |
5597 | void perf_event_header__init_id(struct perf_event_header *header, |
5598 | struct perf_sample_data *data, | |
5599 | struct perf_event *event) | |
c980d109 ACM |
5600 | { |
5601 | if (event->attr.sample_id_all) | |
5602 | __perf_event_header__init_id(header, data, event); | |
5603 | } | |
5604 | ||
5605 | static void __perf_event__output_id_sample(struct perf_output_handle *handle, | |
5606 | struct perf_sample_data *data) | |
5607 | { | |
5608 | u64 sample_type = data->type; | |
5609 | ||
5610 | if (sample_type & PERF_SAMPLE_TID) | |
5611 | perf_output_put(handle, data->tid_entry); | |
5612 | ||
5613 | if (sample_type & PERF_SAMPLE_TIME) | |
5614 | perf_output_put(handle, data->time); | |
5615 | ||
5616 | if (sample_type & PERF_SAMPLE_ID) | |
5617 | perf_output_put(handle, data->id); | |
5618 | ||
5619 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
5620 | perf_output_put(handle, data->stream_id); | |
5621 | ||
5622 | if (sample_type & PERF_SAMPLE_CPU) | |
5623 | perf_output_put(handle, data->cpu_entry); | |
ff3d527c AH |
5624 | |
5625 | if (sample_type & PERF_SAMPLE_IDENTIFIER) | |
5626 | perf_output_put(handle, data->id); | |
c980d109 ACM |
5627 | } |
5628 | ||
76369139 FW |
5629 | void perf_event__output_id_sample(struct perf_event *event, |
5630 | struct perf_output_handle *handle, | |
5631 | struct perf_sample_data *sample) | |
c980d109 ACM |
5632 | { |
5633 | if (event->attr.sample_id_all) | |
5634 | __perf_event__output_id_sample(handle, sample); | |
5635 | } | |
5636 | ||
3dab77fb | 5637 | static void perf_output_read_one(struct perf_output_handle *handle, |
eed01528 SE |
5638 | struct perf_event *event, |
5639 | u64 enabled, u64 running) | |
3dab77fb | 5640 | { |
cdd6c482 | 5641 | u64 read_format = event->attr.read_format; |
3dab77fb PZ |
5642 | u64 values[4]; |
5643 | int n = 0; | |
5644 | ||
b5e58793 | 5645 | values[n++] = perf_event_count(event); |
3dab77fb | 5646 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { |
eed01528 | 5647 | values[n++] = enabled + |
cdd6c482 | 5648 | atomic64_read(&event->child_total_time_enabled); |
3dab77fb PZ |
5649 | } |
5650 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { | |
eed01528 | 5651 | values[n++] = running + |
cdd6c482 | 5652 | atomic64_read(&event->child_total_time_running); |
3dab77fb PZ |
5653 | } |
5654 | if (read_format & PERF_FORMAT_ID) | |
cdd6c482 | 5655 | values[n++] = primary_event_id(event); |
3dab77fb | 5656 | |
76369139 | 5657 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
5658 | } |
5659 | ||
5660 | /* | |
cdd6c482 | 5661 | * XXX PERF_FORMAT_GROUP vs inherited events seems difficult. |
3dab77fb PZ |
5662 | */ |
5663 | static void perf_output_read_group(struct perf_output_handle *handle, | |
eed01528 SE |
5664 | struct perf_event *event, |
5665 | u64 enabled, u64 running) | |
3dab77fb | 5666 | { |
cdd6c482 IM |
5667 | struct perf_event *leader = event->group_leader, *sub; |
5668 | u64 read_format = event->attr.read_format; | |
3dab77fb PZ |
5669 | u64 values[5]; |
5670 | int n = 0; | |
5671 | ||
5672 | values[n++] = 1 + leader->nr_siblings; | |
5673 | ||
5674 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
eed01528 | 5675 | values[n++] = enabled; |
3dab77fb PZ |
5676 | |
5677 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
eed01528 | 5678 | values[n++] = running; |
3dab77fb | 5679 | |
cdd6c482 | 5680 | if (leader != event) |
3dab77fb PZ |
5681 | leader->pmu->read(leader); |
5682 | ||
b5e58793 | 5683 | values[n++] = perf_event_count(leader); |
3dab77fb | 5684 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 5685 | values[n++] = primary_event_id(leader); |
3dab77fb | 5686 | |
76369139 | 5687 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb | 5688 | |
65abc865 | 5689 | list_for_each_entry(sub, &leader->sibling_list, group_entry) { |
3dab77fb PZ |
5690 | n = 0; |
5691 | ||
6f5ab001 JO |
5692 | if ((sub != event) && |
5693 | (sub->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
5694 | sub->pmu->read(sub); |
5695 | ||
b5e58793 | 5696 | values[n++] = perf_event_count(sub); |
3dab77fb | 5697 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 5698 | values[n++] = primary_event_id(sub); |
3dab77fb | 5699 | |
76369139 | 5700 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
5701 | } |
5702 | } | |
5703 | ||
eed01528 SE |
5704 | #define PERF_FORMAT_TOTAL_TIMES (PERF_FORMAT_TOTAL_TIME_ENABLED|\ |
5705 | PERF_FORMAT_TOTAL_TIME_RUNNING) | |
5706 | ||
3dab77fb | 5707 | static void perf_output_read(struct perf_output_handle *handle, |
cdd6c482 | 5708 | struct perf_event *event) |
3dab77fb | 5709 | { |
e3f3541c | 5710 | u64 enabled = 0, running = 0, now; |
eed01528 SE |
5711 | u64 read_format = event->attr.read_format; |
5712 | ||
5713 | /* | |
5714 | * compute total_time_enabled, total_time_running | |
5715 | * based on snapshot values taken when the event | |
5716 | * was last scheduled in. | |
5717 | * | |
5718 | * we cannot simply called update_context_time() | |
5719 | * because of locking issue as we are called in | |
5720 | * NMI context | |
5721 | */ | |
c4794295 | 5722 | if (read_format & PERF_FORMAT_TOTAL_TIMES) |
e3f3541c | 5723 | calc_timer_values(event, &now, &enabled, &running); |
eed01528 | 5724 | |
cdd6c482 | 5725 | if (event->attr.read_format & PERF_FORMAT_GROUP) |
eed01528 | 5726 | perf_output_read_group(handle, event, enabled, running); |
3dab77fb | 5727 | else |
eed01528 | 5728 | perf_output_read_one(handle, event, enabled, running); |
3dab77fb PZ |
5729 | } |
5730 | ||
5622f295 MM |
5731 | void perf_output_sample(struct perf_output_handle *handle, |
5732 | struct perf_event_header *header, | |
5733 | struct perf_sample_data *data, | |
cdd6c482 | 5734 | struct perf_event *event) |
5622f295 MM |
5735 | { |
5736 | u64 sample_type = data->type; | |
5737 | ||
5738 | perf_output_put(handle, *header); | |
5739 | ||
ff3d527c AH |
5740 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
5741 | perf_output_put(handle, data->id); | |
5742 | ||
5622f295 MM |
5743 | if (sample_type & PERF_SAMPLE_IP) |
5744 | perf_output_put(handle, data->ip); | |
5745 | ||
5746 | if (sample_type & PERF_SAMPLE_TID) | |
5747 | perf_output_put(handle, data->tid_entry); | |
5748 | ||
5749 | if (sample_type & PERF_SAMPLE_TIME) | |
5750 | perf_output_put(handle, data->time); | |
5751 | ||
5752 | if (sample_type & PERF_SAMPLE_ADDR) | |
5753 | perf_output_put(handle, data->addr); | |
5754 | ||
5755 | if (sample_type & PERF_SAMPLE_ID) | |
5756 | perf_output_put(handle, data->id); | |
5757 | ||
5758 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
5759 | perf_output_put(handle, data->stream_id); | |
5760 | ||
5761 | if (sample_type & PERF_SAMPLE_CPU) | |
5762 | perf_output_put(handle, data->cpu_entry); | |
5763 | ||
5764 | if (sample_type & PERF_SAMPLE_PERIOD) | |
5765 | perf_output_put(handle, data->period); | |
5766 | ||
5767 | if (sample_type & PERF_SAMPLE_READ) | |
cdd6c482 | 5768 | perf_output_read(handle, event); |
5622f295 MM |
5769 | |
5770 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { | |
5771 | if (data->callchain) { | |
5772 | int size = 1; | |
5773 | ||
5774 | if (data->callchain) | |
5775 | size += data->callchain->nr; | |
5776 | ||
5777 | size *= sizeof(u64); | |
5778 | ||
76369139 | 5779 | __output_copy(handle, data->callchain, size); |
5622f295 MM |
5780 | } else { |
5781 | u64 nr = 0; | |
5782 | perf_output_put(handle, nr); | |
5783 | } | |
5784 | } | |
5785 | ||
5786 | if (sample_type & PERF_SAMPLE_RAW) { | |
7e3f977e DB |
5787 | struct perf_raw_record *raw = data->raw; |
5788 | ||
5789 | if (raw) { | |
5790 | struct perf_raw_frag *frag = &raw->frag; | |
5791 | ||
5792 | perf_output_put(handle, raw->size); | |
5793 | do { | |
5794 | if (frag->copy) { | |
5795 | __output_custom(handle, frag->copy, | |
5796 | frag->data, frag->size); | |
5797 | } else { | |
5798 | __output_copy(handle, frag->data, | |
5799 | frag->size); | |
5800 | } | |
5801 | if (perf_raw_frag_last(frag)) | |
5802 | break; | |
5803 | frag = frag->next; | |
5804 | } while (1); | |
5805 | if (frag->pad) | |
5806 | __output_skip(handle, NULL, frag->pad); | |
5622f295 MM |
5807 | } else { |
5808 | struct { | |
5809 | u32 size; | |
5810 | u32 data; | |
5811 | } raw = { | |
5812 | .size = sizeof(u32), | |
5813 | .data = 0, | |
5814 | }; | |
5815 | perf_output_put(handle, raw); | |
5816 | } | |
5817 | } | |
a7ac67ea | 5818 | |
bce38cd5 SE |
5819 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { |
5820 | if (data->br_stack) { | |
5821 | size_t size; | |
5822 | ||
5823 | size = data->br_stack->nr | |
5824 | * sizeof(struct perf_branch_entry); | |
5825 | ||
5826 | perf_output_put(handle, data->br_stack->nr); | |
5827 | perf_output_copy(handle, data->br_stack->entries, size); | |
5828 | } else { | |
5829 | /* | |
5830 | * we always store at least the value of nr | |
5831 | */ | |
5832 | u64 nr = 0; | |
5833 | perf_output_put(handle, nr); | |
5834 | } | |
5835 | } | |
4018994f JO |
5836 | |
5837 | if (sample_type & PERF_SAMPLE_REGS_USER) { | |
5838 | u64 abi = data->regs_user.abi; | |
5839 | ||
5840 | /* | |
5841 | * If there are no regs to dump, notice it through | |
5842 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
5843 | */ | |
5844 | perf_output_put(handle, abi); | |
5845 | ||
5846 | if (abi) { | |
5847 | u64 mask = event->attr.sample_regs_user; | |
5848 | perf_output_sample_regs(handle, | |
5849 | data->regs_user.regs, | |
5850 | mask); | |
5851 | } | |
5852 | } | |
c5ebcedb | 5853 | |
a5cdd40c | 5854 | if (sample_type & PERF_SAMPLE_STACK_USER) { |
c5ebcedb JO |
5855 | perf_output_sample_ustack(handle, |
5856 | data->stack_user_size, | |
5857 | data->regs_user.regs); | |
a5cdd40c | 5858 | } |
c3feedf2 AK |
5859 | |
5860 | if (sample_type & PERF_SAMPLE_WEIGHT) | |
5861 | perf_output_put(handle, data->weight); | |
d6be9ad6 SE |
5862 | |
5863 | if (sample_type & PERF_SAMPLE_DATA_SRC) | |
5864 | perf_output_put(handle, data->data_src.val); | |
a5cdd40c | 5865 | |
fdfbbd07 AK |
5866 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
5867 | perf_output_put(handle, data->txn); | |
5868 | ||
60e2364e SE |
5869 | if (sample_type & PERF_SAMPLE_REGS_INTR) { |
5870 | u64 abi = data->regs_intr.abi; | |
5871 | /* | |
5872 | * If there are no regs to dump, notice it through | |
5873 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
5874 | */ | |
5875 | perf_output_put(handle, abi); | |
5876 | ||
5877 | if (abi) { | |
5878 | u64 mask = event->attr.sample_regs_intr; | |
5879 | ||
5880 | perf_output_sample_regs(handle, | |
5881 | data->regs_intr.regs, | |
5882 | mask); | |
5883 | } | |
5884 | } | |
5885 | ||
a5cdd40c PZ |
5886 | if (!event->attr.watermark) { |
5887 | int wakeup_events = event->attr.wakeup_events; | |
5888 | ||
5889 | if (wakeup_events) { | |
5890 | struct ring_buffer *rb = handle->rb; | |
5891 | int events = local_inc_return(&rb->events); | |
5892 | ||
5893 | if (events >= wakeup_events) { | |
5894 | local_sub(wakeup_events, &rb->events); | |
5895 | local_inc(&rb->wakeup); | |
5896 | } | |
5897 | } | |
5898 | } | |
5622f295 MM |
5899 | } |
5900 | ||
5901 | void perf_prepare_sample(struct perf_event_header *header, | |
5902 | struct perf_sample_data *data, | |
cdd6c482 | 5903 | struct perf_event *event, |
5622f295 | 5904 | struct pt_regs *regs) |
7b732a75 | 5905 | { |
cdd6c482 | 5906 | u64 sample_type = event->attr.sample_type; |
7b732a75 | 5907 | |
cdd6c482 | 5908 | header->type = PERF_RECORD_SAMPLE; |
c320c7b7 | 5909 | header->size = sizeof(*header) + event->header_size; |
5622f295 MM |
5910 | |
5911 | header->misc = 0; | |
5912 | header->misc |= perf_misc_flags(regs); | |
6fab0192 | 5913 | |
c980d109 | 5914 | __perf_event_header__init_id(header, data, event); |
6844c09d | 5915 | |
c320c7b7 | 5916 | if (sample_type & PERF_SAMPLE_IP) |
5622f295 MM |
5917 | data->ip = perf_instruction_pointer(regs); |
5918 | ||
b23f3325 | 5919 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { |
5622f295 | 5920 | int size = 1; |
394ee076 | 5921 | |
e6dab5ff | 5922 | data->callchain = perf_callchain(event, regs); |
5622f295 MM |
5923 | |
5924 | if (data->callchain) | |
5925 | size += data->callchain->nr; | |
5926 | ||
5927 | header->size += size * sizeof(u64); | |
394ee076 PZ |
5928 | } |
5929 | ||
3a43ce68 | 5930 | if (sample_type & PERF_SAMPLE_RAW) { |
7e3f977e DB |
5931 | struct perf_raw_record *raw = data->raw; |
5932 | int size; | |
5933 | ||
5934 | if (raw) { | |
5935 | struct perf_raw_frag *frag = &raw->frag; | |
5936 | u32 sum = 0; | |
5937 | ||
5938 | do { | |
5939 | sum += frag->size; | |
5940 | if (perf_raw_frag_last(frag)) | |
5941 | break; | |
5942 | frag = frag->next; | |
5943 | } while (1); | |
5944 | ||
5945 | size = round_up(sum + sizeof(u32), sizeof(u64)); | |
5946 | raw->size = size - sizeof(u32); | |
5947 | frag->pad = raw->size - sum; | |
5948 | } else { | |
5949 | size = sizeof(u64); | |
5950 | } | |
a044560c | 5951 | |
7e3f977e | 5952 | header->size += size; |
7f453c24 | 5953 | } |
bce38cd5 SE |
5954 | |
5955 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { | |
5956 | int size = sizeof(u64); /* nr */ | |
5957 | if (data->br_stack) { | |
5958 | size += data->br_stack->nr | |
5959 | * sizeof(struct perf_branch_entry); | |
5960 | } | |
5961 | header->size += size; | |
5962 | } | |
4018994f | 5963 | |
2565711f | 5964 | if (sample_type & (PERF_SAMPLE_REGS_USER | PERF_SAMPLE_STACK_USER)) |
88a7c26a AL |
5965 | perf_sample_regs_user(&data->regs_user, regs, |
5966 | &data->regs_user_copy); | |
2565711f | 5967 | |
4018994f JO |
5968 | if (sample_type & PERF_SAMPLE_REGS_USER) { |
5969 | /* regs dump ABI info */ | |
5970 | int size = sizeof(u64); | |
5971 | ||
4018994f JO |
5972 | if (data->regs_user.regs) { |
5973 | u64 mask = event->attr.sample_regs_user; | |
5974 | size += hweight64(mask) * sizeof(u64); | |
5975 | } | |
5976 | ||
5977 | header->size += size; | |
5978 | } | |
c5ebcedb JO |
5979 | |
5980 | if (sample_type & PERF_SAMPLE_STACK_USER) { | |
5981 | /* | |
5982 | * Either we need PERF_SAMPLE_STACK_USER bit to be allways | |
5983 | * processed as the last one or have additional check added | |
5984 | * in case new sample type is added, because we could eat | |
5985 | * up the rest of the sample size. | |
5986 | */ | |
c5ebcedb JO |
5987 | u16 stack_size = event->attr.sample_stack_user; |
5988 | u16 size = sizeof(u64); | |
5989 | ||
c5ebcedb | 5990 | stack_size = perf_sample_ustack_size(stack_size, header->size, |
2565711f | 5991 | data->regs_user.regs); |
c5ebcedb JO |
5992 | |
5993 | /* | |
5994 | * If there is something to dump, add space for the dump | |
5995 | * itself and for the field that tells the dynamic size, | |
5996 | * which is how many have been actually dumped. | |
5997 | */ | |
5998 | if (stack_size) | |
5999 | size += sizeof(u64) + stack_size; | |
6000 | ||
6001 | data->stack_user_size = stack_size; | |
6002 | header->size += size; | |
6003 | } | |
60e2364e SE |
6004 | |
6005 | if (sample_type & PERF_SAMPLE_REGS_INTR) { | |
6006 | /* regs dump ABI info */ | |
6007 | int size = sizeof(u64); | |
6008 | ||
6009 | perf_sample_regs_intr(&data->regs_intr, regs); | |
6010 | ||
6011 | if (data->regs_intr.regs) { | |
6012 | u64 mask = event->attr.sample_regs_intr; | |
6013 | ||
6014 | size += hweight64(mask) * sizeof(u64); | |
6015 | } | |
6016 | ||
6017 | header->size += size; | |
6018 | } | |
5622f295 | 6019 | } |
7f453c24 | 6020 | |
9ecda41a WN |
6021 | static void __always_inline |
6022 | __perf_event_output(struct perf_event *event, | |
6023 | struct perf_sample_data *data, | |
6024 | struct pt_regs *regs, | |
6025 | int (*output_begin)(struct perf_output_handle *, | |
6026 | struct perf_event *, | |
6027 | unsigned int)) | |
5622f295 MM |
6028 | { |
6029 | struct perf_output_handle handle; | |
6030 | struct perf_event_header header; | |
689802b2 | 6031 | |
927c7a9e FW |
6032 | /* protect the callchain buffers */ |
6033 | rcu_read_lock(); | |
6034 | ||
cdd6c482 | 6035 | perf_prepare_sample(&header, data, event, regs); |
5c148194 | 6036 | |
9ecda41a | 6037 | if (output_begin(&handle, event, header.size)) |
927c7a9e | 6038 | goto exit; |
0322cd6e | 6039 | |
cdd6c482 | 6040 | perf_output_sample(&handle, &header, data, event); |
f413cdb8 | 6041 | |
8a057d84 | 6042 | perf_output_end(&handle); |
927c7a9e FW |
6043 | |
6044 | exit: | |
6045 | rcu_read_unlock(); | |
0322cd6e PZ |
6046 | } |
6047 | ||
9ecda41a WN |
6048 | void |
6049 | perf_event_output_forward(struct perf_event *event, | |
6050 | struct perf_sample_data *data, | |
6051 | struct pt_regs *regs) | |
6052 | { | |
6053 | __perf_event_output(event, data, regs, perf_output_begin_forward); | |
6054 | } | |
6055 | ||
6056 | void | |
6057 | perf_event_output_backward(struct perf_event *event, | |
6058 | struct perf_sample_data *data, | |
6059 | struct pt_regs *regs) | |
6060 | { | |
6061 | __perf_event_output(event, data, regs, perf_output_begin_backward); | |
6062 | } | |
6063 | ||
6064 | void | |
6065 | perf_event_output(struct perf_event *event, | |
6066 | struct perf_sample_data *data, | |
6067 | struct pt_regs *regs) | |
6068 | { | |
6069 | __perf_event_output(event, data, regs, perf_output_begin); | |
6070 | } | |
6071 | ||
38b200d6 | 6072 | /* |
cdd6c482 | 6073 | * read event_id |
38b200d6 PZ |
6074 | */ |
6075 | ||
6076 | struct perf_read_event { | |
6077 | struct perf_event_header header; | |
6078 | ||
6079 | u32 pid; | |
6080 | u32 tid; | |
38b200d6 PZ |
6081 | }; |
6082 | ||
6083 | static void | |
cdd6c482 | 6084 | perf_event_read_event(struct perf_event *event, |
38b200d6 PZ |
6085 | struct task_struct *task) |
6086 | { | |
6087 | struct perf_output_handle handle; | |
c980d109 | 6088 | struct perf_sample_data sample; |
dfc65094 | 6089 | struct perf_read_event read_event = { |
38b200d6 | 6090 | .header = { |
cdd6c482 | 6091 | .type = PERF_RECORD_READ, |
38b200d6 | 6092 | .misc = 0, |
c320c7b7 | 6093 | .size = sizeof(read_event) + event->read_size, |
38b200d6 | 6094 | }, |
cdd6c482 IM |
6095 | .pid = perf_event_pid(event, task), |
6096 | .tid = perf_event_tid(event, task), | |
38b200d6 | 6097 | }; |
3dab77fb | 6098 | int ret; |
38b200d6 | 6099 | |
c980d109 | 6100 | perf_event_header__init_id(&read_event.header, &sample, event); |
a7ac67ea | 6101 | ret = perf_output_begin(&handle, event, read_event.header.size); |
38b200d6 PZ |
6102 | if (ret) |
6103 | return; | |
6104 | ||
dfc65094 | 6105 | perf_output_put(&handle, read_event); |
cdd6c482 | 6106 | perf_output_read(&handle, event); |
c980d109 | 6107 | perf_event__output_id_sample(event, &handle, &sample); |
3dab77fb | 6108 | |
38b200d6 PZ |
6109 | perf_output_end(&handle); |
6110 | } | |
6111 | ||
aab5b71e | 6112 | typedef void (perf_iterate_f)(struct perf_event *event, void *data); |
52d857a8 JO |
6113 | |
6114 | static void | |
aab5b71e PZ |
6115 | perf_iterate_ctx(struct perf_event_context *ctx, |
6116 | perf_iterate_f output, | |
b73e4fef | 6117 | void *data, bool all) |
52d857a8 JO |
6118 | { |
6119 | struct perf_event *event; | |
6120 | ||
6121 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
b73e4fef AS |
6122 | if (!all) { |
6123 | if (event->state < PERF_EVENT_STATE_INACTIVE) | |
6124 | continue; | |
6125 | if (!event_filter_match(event)) | |
6126 | continue; | |
6127 | } | |
6128 | ||
67516844 | 6129 | output(event, data); |
52d857a8 JO |
6130 | } |
6131 | } | |
6132 | ||
aab5b71e | 6133 | static void perf_iterate_sb_cpu(perf_iterate_f output, void *data) |
f2fb6bef KL |
6134 | { |
6135 | struct pmu_event_list *pel = this_cpu_ptr(&pmu_sb_events); | |
6136 | struct perf_event *event; | |
6137 | ||
6138 | list_for_each_entry_rcu(event, &pel->list, sb_list) { | |
0b8f1e2e PZ |
6139 | /* |
6140 | * Skip events that are not fully formed yet; ensure that | |
6141 | * if we observe event->ctx, both event and ctx will be | |
6142 | * complete enough. See perf_install_in_context(). | |
6143 | */ | |
6144 | if (!smp_load_acquire(&event->ctx)) | |
6145 | continue; | |
6146 | ||
f2fb6bef KL |
6147 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
6148 | continue; | |
6149 | if (!event_filter_match(event)) | |
6150 | continue; | |
6151 | output(event, data); | |
6152 | } | |
6153 | } | |
6154 | ||
aab5b71e PZ |
6155 | /* |
6156 | * Iterate all events that need to receive side-band events. | |
6157 | * | |
6158 | * For new callers; ensure that account_pmu_sb_event() includes | |
6159 | * your event, otherwise it might not get delivered. | |
6160 | */ | |
52d857a8 | 6161 | static void |
aab5b71e | 6162 | perf_iterate_sb(perf_iterate_f output, void *data, |
52d857a8 JO |
6163 | struct perf_event_context *task_ctx) |
6164 | { | |
52d857a8 | 6165 | struct perf_event_context *ctx; |
52d857a8 JO |
6166 | int ctxn; |
6167 | ||
aab5b71e PZ |
6168 | rcu_read_lock(); |
6169 | preempt_disable(); | |
6170 | ||
4e93ad60 | 6171 | /* |
aab5b71e PZ |
6172 | * If we have task_ctx != NULL we only notify the task context itself. |
6173 | * The task_ctx is set only for EXIT events before releasing task | |
4e93ad60 JO |
6174 | * context. |
6175 | */ | |
6176 | if (task_ctx) { | |
aab5b71e PZ |
6177 | perf_iterate_ctx(task_ctx, output, data, false); |
6178 | goto done; | |
4e93ad60 JO |
6179 | } |
6180 | ||
aab5b71e | 6181 | perf_iterate_sb_cpu(output, data); |
f2fb6bef KL |
6182 | |
6183 | for_each_task_context_nr(ctxn) { | |
52d857a8 JO |
6184 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); |
6185 | if (ctx) | |
aab5b71e | 6186 | perf_iterate_ctx(ctx, output, data, false); |
52d857a8 | 6187 | } |
aab5b71e | 6188 | done: |
f2fb6bef | 6189 | preempt_enable(); |
52d857a8 | 6190 | rcu_read_unlock(); |
95ff4ca2 AS |
6191 | } |
6192 | ||
375637bc AS |
6193 | /* |
6194 | * Clear all file-based filters at exec, they'll have to be | |
6195 | * re-instated when/if these objects are mmapped again. | |
6196 | */ | |
6197 | static void perf_event_addr_filters_exec(struct perf_event *event, void *data) | |
6198 | { | |
6199 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
6200 | struct perf_addr_filter *filter; | |
6201 | unsigned int restart = 0, count = 0; | |
6202 | unsigned long flags; | |
6203 | ||
6204 | if (!has_addr_filter(event)) | |
6205 | return; | |
6206 | ||
6207 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
6208 | list_for_each_entry(filter, &ifh->list, entry) { | |
6209 | if (filter->inode) { | |
6210 | event->addr_filters_offs[count] = 0; | |
6211 | restart++; | |
6212 | } | |
6213 | ||
6214 | count++; | |
6215 | } | |
6216 | ||
6217 | if (restart) | |
6218 | event->addr_filters_gen++; | |
6219 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
6220 | ||
6221 | if (restart) | |
767ae086 | 6222 | perf_event_stop(event, 1); |
375637bc AS |
6223 | } |
6224 | ||
6225 | void perf_event_exec(void) | |
6226 | { | |
6227 | struct perf_event_context *ctx; | |
6228 | int ctxn; | |
6229 | ||
6230 | rcu_read_lock(); | |
6231 | for_each_task_context_nr(ctxn) { | |
6232 | ctx = current->perf_event_ctxp[ctxn]; | |
6233 | if (!ctx) | |
6234 | continue; | |
6235 | ||
6236 | perf_event_enable_on_exec(ctxn); | |
6237 | ||
aab5b71e | 6238 | perf_iterate_ctx(ctx, perf_event_addr_filters_exec, NULL, |
375637bc AS |
6239 | true); |
6240 | } | |
6241 | rcu_read_unlock(); | |
6242 | } | |
6243 | ||
95ff4ca2 AS |
6244 | struct remote_output { |
6245 | struct ring_buffer *rb; | |
6246 | int err; | |
6247 | }; | |
6248 | ||
6249 | static void __perf_event_output_stop(struct perf_event *event, void *data) | |
6250 | { | |
6251 | struct perf_event *parent = event->parent; | |
6252 | struct remote_output *ro = data; | |
6253 | struct ring_buffer *rb = ro->rb; | |
375637bc AS |
6254 | struct stop_event_data sd = { |
6255 | .event = event, | |
6256 | }; | |
95ff4ca2 AS |
6257 | |
6258 | if (!has_aux(event)) | |
6259 | return; | |
6260 | ||
6261 | if (!parent) | |
6262 | parent = event; | |
6263 | ||
6264 | /* | |
6265 | * In case of inheritance, it will be the parent that links to the | |
767ae086 AS |
6266 | * ring-buffer, but it will be the child that's actually using it. |
6267 | * | |
6268 | * We are using event::rb to determine if the event should be stopped, | |
6269 | * however this may race with ring_buffer_attach() (through set_output), | |
6270 | * which will make us skip the event that actually needs to be stopped. | |
6271 | * So ring_buffer_attach() has to stop an aux event before re-assigning | |
6272 | * its rb pointer. | |
95ff4ca2 AS |
6273 | */ |
6274 | if (rcu_dereference(parent->rb) == rb) | |
375637bc | 6275 | ro->err = __perf_event_stop(&sd); |
95ff4ca2 AS |
6276 | } |
6277 | ||
6278 | static int __perf_pmu_output_stop(void *info) | |
6279 | { | |
6280 | struct perf_event *event = info; | |
6281 | struct pmu *pmu = event->pmu; | |
8b6a3fe8 | 6282 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
95ff4ca2 AS |
6283 | struct remote_output ro = { |
6284 | .rb = event->rb, | |
6285 | }; | |
6286 | ||
6287 | rcu_read_lock(); | |
aab5b71e | 6288 | perf_iterate_ctx(&cpuctx->ctx, __perf_event_output_stop, &ro, false); |
95ff4ca2 | 6289 | if (cpuctx->task_ctx) |
aab5b71e | 6290 | perf_iterate_ctx(cpuctx->task_ctx, __perf_event_output_stop, |
b73e4fef | 6291 | &ro, false); |
95ff4ca2 AS |
6292 | rcu_read_unlock(); |
6293 | ||
6294 | return ro.err; | |
6295 | } | |
6296 | ||
6297 | static void perf_pmu_output_stop(struct perf_event *event) | |
6298 | { | |
6299 | struct perf_event *iter; | |
6300 | int err, cpu; | |
6301 | ||
6302 | restart: | |
6303 | rcu_read_lock(); | |
6304 | list_for_each_entry_rcu(iter, &event->rb->event_list, rb_entry) { | |
6305 | /* | |
6306 | * For per-CPU events, we need to make sure that neither they | |
6307 | * nor their children are running; for cpu==-1 events it's | |
6308 | * sufficient to stop the event itself if it's active, since | |
6309 | * it can't have children. | |
6310 | */ | |
6311 | cpu = iter->cpu; | |
6312 | if (cpu == -1) | |
6313 | cpu = READ_ONCE(iter->oncpu); | |
6314 | ||
6315 | if (cpu == -1) | |
6316 | continue; | |
6317 | ||
6318 | err = cpu_function_call(cpu, __perf_pmu_output_stop, event); | |
6319 | if (err == -EAGAIN) { | |
6320 | rcu_read_unlock(); | |
6321 | goto restart; | |
6322 | } | |
6323 | } | |
6324 | rcu_read_unlock(); | |
52d857a8 JO |
6325 | } |
6326 | ||
60313ebe | 6327 | /* |
9f498cc5 PZ |
6328 | * task tracking -- fork/exit |
6329 | * | |
13d7a241 | 6330 | * enabled by: attr.comm | attr.mmap | attr.mmap2 | attr.mmap_data | attr.task |
60313ebe PZ |
6331 | */ |
6332 | ||
9f498cc5 | 6333 | struct perf_task_event { |
3a80b4a3 | 6334 | struct task_struct *task; |
cdd6c482 | 6335 | struct perf_event_context *task_ctx; |
60313ebe PZ |
6336 | |
6337 | struct { | |
6338 | struct perf_event_header header; | |
6339 | ||
6340 | u32 pid; | |
6341 | u32 ppid; | |
9f498cc5 PZ |
6342 | u32 tid; |
6343 | u32 ptid; | |
393b2ad8 | 6344 | u64 time; |
cdd6c482 | 6345 | } event_id; |
60313ebe PZ |
6346 | }; |
6347 | ||
67516844 JO |
6348 | static int perf_event_task_match(struct perf_event *event) |
6349 | { | |
13d7a241 SE |
6350 | return event->attr.comm || event->attr.mmap || |
6351 | event->attr.mmap2 || event->attr.mmap_data || | |
6352 | event->attr.task; | |
67516844 JO |
6353 | } |
6354 | ||
cdd6c482 | 6355 | static void perf_event_task_output(struct perf_event *event, |
52d857a8 | 6356 | void *data) |
60313ebe | 6357 | { |
52d857a8 | 6358 | struct perf_task_event *task_event = data; |
60313ebe | 6359 | struct perf_output_handle handle; |
c980d109 | 6360 | struct perf_sample_data sample; |
9f498cc5 | 6361 | struct task_struct *task = task_event->task; |
c980d109 | 6362 | int ret, size = task_event->event_id.header.size; |
8bb39f9a | 6363 | |
67516844 JO |
6364 | if (!perf_event_task_match(event)) |
6365 | return; | |
6366 | ||
c980d109 | 6367 | perf_event_header__init_id(&task_event->event_id.header, &sample, event); |
60313ebe | 6368 | |
c980d109 | 6369 | ret = perf_output_begin(&handle, event, |
a7ac67ea | 6370 | task_event->event_id.header.size); |
ef60777c | 6371 | if (ret) |
c980d109 | 6372 | goto out; |
60313ebe | 6373 | |
cdd6c482 IM |
6374 | task_event->event_id.pid = perf_event_pid(event, task); |
6375 | task_event->event_id.ppid = perf_event_pid(event, current); | |
60313ebe | 6376 | |
cdd6c482 IM |
6377 | task_event->event_id.tid = perf_event_tid(event, task); |
6378 | task_event->event_id.ptid = perf_event_tid(event, current); | |
9f498cc5 | 6379 | |
34f43927 PZ |
6380 | task_event->event_id.time = perf_event_clock(event); |
6381 | ||
cdd6c482 | 6382 | perf_output_put(&handle, task_event->event_id); |
393b2ad8 | 6383 | |
c980d109 ACM |
6384 | perf_event__output_id_sample(event, &handle, &sample); |
6385 | ||
60313ebe | 6386 | perf_output_end(&handle); |
c980d109 ACM |
6387 | out: |
6388 | task_event->event_id.header.size = size; | |
60313ebe PZ |
6389 | } |
6390 | ||
cdd6c482 IM |
6391 | static void perf_event_task(struct task_struct *task, |
6392 | struct perf_event_context *task_ctx, | |
3a80b4a3 | 6393 | int new) |
60313ebe | 6394 | { |
9f498cc5 | 6395 | struct perf_task_event task_event; |
60313ebe | 6396 | |
cdd6c482 IM |
6397 | if (!atomic_read(&nr_comm_events) && |
6398 | !atomic_read(&nr_mmap_events) && | |
6399 | !atomic_read(&nr_task_events)) | |
60313ebe PZ |
6400 | return; |
6401 | ||
9f498cc5 | 6402 | task_event = (struct perf_task_event){ |
3a80b4a3 PZ |
6403 | .task = task, |
6404 | .task_ctx = task_ctx, | |
cdd6c482 | 6405 | .event_id = { |
60313ebe | 6406 | .header = { |
cdd6c482 | 6407 | .type = new ? PERF_RECORD_FORK : PERF_RECORD_EXIT, |
573402db | 6408 | .misc = 0, |
cdd6c482 | 6409 | .size = sizeof(task_event.event_id), |
60313ebe | 6410 | }, |
573402db PZ |
6411 | /* .pid */ |
6412 | /* .ppid */ | |
9f498cc5 PZ |
6413 | /* .tid */ |
6414 | /* .ptid */ | |
34f43927 | 6415 | /* .time */ |
60313ebe PZ |
6416 | }, |
6417 | }; | |
6418 | ||
aab5b71e | 6419 | perf_iterate_sb(perf_event_task_output, |
52d857a8 JO |
6420 | &task_event, |
6421 | task_ctx); | |
9f498cc5 PZ |
6422 | } |
6423 | ||
cdd6c482 | 6424 | void perf_event_fork(struct task_struct *task) |
9f498cc5 | 6425 | { |
cdd6c482 | 6426 | perf_event_task(task, NULL, 1); |
60313ebe PZ |
6427 | } |
6428 | ||
8d1b2d93 PZ |
6429 | /* |
6430 | * comm tracking | |
6431 | */ | |
6432 | ||
6433 | struct perf_comm_event { | |
22a4f650 IM |
6434 | struct task_struct *task; |
6435 | char *comm; | |
8d1b2d93 PZ |
6436 | int comm_size; |
6437 | ||
6438 | struct { | |
6439 | struct perf_event_header header; | |
6440 | ||
6441 | u32 pid; | |
6442 | u32 tid; | |
cdd6c482 | 6443 | } event_id; |
8d1b2d93 PZ |
6444 | }; |
6445 | ||
67516844 JO |
6446 | static int perf_event_comm_match(struct perf_event *event) |
6447 | { | |
6448 | return event->attr.comm; | |
6449 | } | |
6450 | ||
cdd6c482 | 6451 | static void perf_event_comm_output(struct perf_event *event, |
52d857a8 | 6452 | void *data) |
8d1b2d93 | 6453 | { |
52d857a8 | 6454 | struct perf_comm_event *comm_event = data; |
8d1b2d93 | 6455 | struct perf_output_handle handle; |
c980d109 | 6456 | struct perf_sample_data sample; |
cdd6c482 | 6457 | int size = comm_event->event_id.header.size; |
c980d109 ACM |
6458 | int ret; |
6459 | ||
67516844 JO |
6460 | if (!perf_event_comm_match(event)) |
6461 | return; | |
6462 | ||
c980d109 ACM |
6463 | perf_event_header__init_id(&comm_event->event_id.header, &sample, event); |
6464 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 6465 | comm_event->event_id.header.size); |
8d1b2d93 PZ |
6466 | |
6467 | if (ret) | |
c980d109 | 6468 | goto out; |
8d1b2d93 | 6469 | |
cdd6c482 IM |
6470 | comm_event->event_id.pid = perf_event_pid(event, comm_event->task); |
6471 | comm_event->event_id.tid = perf_event_tid(event, comm_event->task); | |
709e50cf | 6472 | |
cdd6c482 | 6473 | perf_output_put(&handle, comm_event->event_id); |
76369139 | 6474 | __output_copy(&handle, comm_event->comm, |
8d1b2d93 | 6475 | comm_event->comm_size); |
c980d109 ACM |
6476 | |
6477 | perf_event__output_id_sample(event, &handle, &sample); | |
6478 | ||
8d1b2d93 | 6479 | perf_output_end(&handle); |
c980d109 ACM |
6480 | out: |
6481 | comm_event->event_id.header.size = size; | |
8d1b2d93 PZ |
6482 | } |
6483 | ||
cdd6c482 | 6484 | static void perf_event_comm_event(struct perf_comm_event *comm_event) |
8d1b2d93 | 6485 | { |
413ee3b4 | 6486 | char comm[TASK_COMM_LEN]; |
8d1b2d93 | 6487 | unsigned int size; |
8d1b2d93 | 6488 | |
413ee3b4 | 6489 | memset(comm, 0, sizeof(comm)); |
96b02d78 | 6490 | strlcpy(comm, comm_event->task->comm, sizeof(comm)); |
888fcee0 | 6491 | size = ALIGN(strlen(comm)+1, sizeof(u64)); |
8d1b2d93 PZ |
6492 | |
6493 | comm_event->comm = comm; | |
6494 | comm_event->comm_size = size; | |
6495 | ||
cdd6c482 | 6496 | comm_event->event_id.header.size = sizeof(comm_event->event_id) + size; |
8dc85d54 | 6497 | |
aab5b71e | 6498 | perf_iterate_sb(perf_event_comm_output, |
52d857a8 JO |
6499 | comm_event, |
6500 | NULL); | |
8d1b2d93 PZ |
6501 | } |
6502 | ||
82b89778 | 6503 | void perf_event_comm(struct task_struct *task, bool exec) |
8d1b2d93 | 6504 | { |
9ee318a7 PZ |
6505 | struct perf_comm_event comm_event; |
6506 | ||
cdd6c482 | 6507 | if (!atomic_read(&nr_comm_events)) |
9ee318a7 | 6508 | return; |
a63eaf34 | 6509 | |
9ee318a7 | 6510 | comm_event = (struct perf_comm_event){ |
8d1b2d93 | 6511 | .task = task, |
573402db PZ |
6512 | /* .comm */ |
6513 | /* .comm_size */ | |
cdd6c482 | 6514 | .event_id = { |
573402db | 6515 | .header = { |
cdd6c482 | 6516 | .type = PERF_RECORD_COMM, |
82b89778 | 6517 | .misc = exec ? PERF_RECORD_MISC_COMM_EXEC : 0, |
573402db PZ |
6518 | /* .size */ |
6519 | }, | |
6520 | /* .pid */ | |
6521 | /* .tid */ | |
8d1b2d93 PZ |
6522 | }, |
6523 | }; | |
6524 | ||
cdd6c482 | 6525 | perf_event_comm_event(&comm_event); |
8d1b2d93 PZ |
6526 | } |
6527 | ||
0a4a9391 PZ |
6528 | /* |
6529 | * mmap tracking | |
6530 | */ | |
6531 | ||
6532 | struct perf_mmap_event { | |
089dd79d PZ |
6533 | struct vm_area_struct *vma; |
6534 | ||
6535 | const char *file_name; | |
6536 | int file_size; | |
13d7a241 SE |
6537 | int maj, min; |
6538 | u64 ino; | |
6539 | u64 ino_generation; | |
f972eb63 | 6540 | u32 prot, flags; |
0a4a9391 PZ |
6541 | |
6542 | struct { | |
6543 | struct perf_event_header header; | |
6544 | ||
6545 | u32 pid; | |
6546 | u32 tid; | |
6547 | u64 start; | |
6548 | u64 len; | |
6549 | u64 pgoff; | |
cdd6c482 | 6550 | } event_id; |
0a4a9391 PZ |
6551 | }; |
6552 | ||
67516844 JO |
6553 | static int perf_event_mmap_match(struct perf_event *event, |
6554 | void *data) | |
6555 | { | |
6556 | struct perf_mmap_event *mmap_event = data; | |
6557 | struct vm_area_struct *vma = mmap_event->vma; | |
6558 | int executable = vma->vm_flags & VM_EXEC; | |
6559 | ||
6560 | return (!executable && event->attr.mmap_data) || | |
13d7a241 | 6561 | (executable && (event->attr.mmap || event->attr.mmap2)); |
67516844 JO |
6562 | } |
6563 | ||
cdd6c482 | 6564 | static void perf_event_mmap_output(struct perf_event *event, |
52d857a8 | 6565 | void *data) |
0a4a9391 | 6566 | { |
52d857a8 | 6567 | struct perf_mmap_event *mmap_event = data; |
0a4a9391 | 6568 | struct perf_output_handle handle; |
c980d109 | 6569 | struct perf_sample_data sample; |
cdd6c482 | 6570 | int size = mmap_event->event_id.header.size; |
c980d109 | 6571 | int ret; |
0a4a9391 | 6572 | |
67516844 JO |
6573 | if (!perf_event_mmap_match(event, data)) |
6574 | return; | |
6575 | ||
13d7a241 SE |
6576 | if (event->attr.mmap2) { |
6577 | mmap_event->event_id.header.type = PERF_RECORD_MMAP2; | |
6578 | mmap_event->event_id.header.size += sizeof(mmap_event->maj); | |
6579 | mmap_event->event_id.header.size += sizeof(mmap_event->min); | |
6580 | mmap_event->event_id.header.size += sizeof(mmap_event->ino); | |
d008d525 | 6581 | mmap_event->event_id.header.size += sizeof(mmap_event->ino_generation); |
f972eb63 PZ |
6582 | mmap_event->event_id.header.size += sizeof(mmap_event->prot); |
6583 | mmap_event->event_id.header.size += sizeof(mmap_event->flags); | |
13d7a241 SE |
6584 | } |
6585 | ||
c980d109 ACM |
6586 | perf_event_header__init_id(&mmap_event->event_id.header, &sample, event); |
6587 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 6588 | mmap_event->event_id.header.size); |
0a4a9391 | 6589 | if (ret) |
c980d109 | 6590 | goto out; |
0a4a9391 | 6591 | |
cdd6c482 IM |
6592 | mmap_event->event_id.pid = perf_event_pid(event, current); |
6593 | mmap_event->event_id.tid = perf_event_tid(event, current); | |
709e50cf | 6594 | |
cdd6c482 | 6595 | perf_output_put(&handle, mmap_event->event_id); |
13d7a241 SE |
6596 | |
6597 | if (event->attr.mmap2) { | |
6598 | perf_output_put(&handle, mmap_event->maj); | |
6599 | perf_output_put(&handle, mmap_event->min); | |
6600 | perf_output_put(&handle, mmap_event->ino); | |
6601 | perf_output_put(&handle, mmap_event->ino_generation); | |
f972eb63 PZ |
6602 | perf_output_put(&handle, mmap_event->prot); |
6603 | perf_output_put(&handle, mmap_event->flags); | |
13d7a241 SE |
6604 | } |
6605 | ||
76369139 | 6606 | __output_copy(&handle, mmap_event->file_name, |
0a4a9391 | 6607 | mmap_event->file_size); |
c980d109 ACM |
6608 | |
6609 | perf_event__output_id_sample(event, &handle, &sample); | |
6610 | ||
78d613eb | 6611 | perf_output_end(&handle); |
c980d109 ACM |
6612 | out: |
6613 | mmap_event->event_id.header.size = size; | |
0a4a9391 PZ |
6614 | } |
6615 | ||
cdd6c482 | 6616 | static void perf_event_mmap_event(struct perf_mmap_event *mmap_event) |
0a4a9391 | 6617 | { |
089dd79d PZ |
6618 | struct vm_area_struct *vma = mmap_event->vma; |
6619 | struct file *file = vma->vm_file; | |
13d7a241 SE |
6620 | int maj = 0, min = 0; |
6621 | u64 ino = 0, gen = 0; | |
f972eb63 | 6622 | u32 prot = 0, flags = 0; |
0a4a9391 PZ |
6623 | unsigned int size; |
6624 | char tmp[16]; | |
6625 | char *buf = NULL; | |
2c42cfbf | 6626 | char *name; |
413ee3b4 | 6627 | |
0b3589be PZ |
6628 | if (vma->vm_flags & VM_READ) |
6629 | prot |= PROT_READ; | |
6630 | if (vma->vm_flags & VM_WRITE) | |
6631 | prot |= PROT_WRITE; | |
6632 | if (vma->vm_flags & VM_EXEC) | |
6633 | prot |= PROT_EXEC; | |
6634 | ||
6635 | if (vma->vm_flags & VM_MAYSHARE) | |
6636 | flags = MAP_SHARED; | |
6637 | else | |
6638 | flags = MAP_PRIVATE; | |
6639 | ||
6640 | if (vma->vm_flags & VM_DENYWRITE) | |
6641 | flags |= MAP_DENYWRITE; | |
6642 | if (vma->vm_flags & VM_MAYEXEC) | |
6643 | flags |= MAP_EXECUTABLE; | |
6644 | if (vma->vm_flags & VM_LOCKED) | |
6645 | flags |= MAP_LOCKED; | |
6646 | if (vma->vm_flags & VM_HUGETLB) | |
6647 | flags |= MAP_HUGETLB; | |
6648 | ||
0a4a9391 | 6649 | if (file) { |
13d7a241 SE |
6650 | struct inode *inode; |
6651 | dev_t dev; | |
3ea2f2b9 | 6652 | |
2c42cfbf | 6653 | buf = kmalloc(PATH_MAX, GFP_KERNEL); |
0a4a9391 | 6654 | if (!buf) { |
c7e548b4 ON |
6655 | name = "//enomem"; |
6656 | goto cpy_name; | |
0a4a9391 | 6657 | } |
413ee3b4 | 6658 | /* |
3ea2f2b9 | 6659 | * d_path() works from the end of the rb backwards, so we |
413ee3b4 AB |
6660 | * need to add enough zero bytes after the string to handle |
6661 | * the 64bit alignment we do later. | |
6662 | */ | |
9bf39ab2 | 6663 | name = file_path(file, buf, PATH_MAX - sizeof(u64)); |
0a4a9391 | 6664 | if (IS_ERR(name)) { |
c7e548b4 ON |
6665 | name = "//toolong"; |
6666 | goto cpy_name; | |
0a4a9391 | 6667 | } |
13d7a241 SE |
6668 | inode = file_inode(vma->vm_file); |
6669 | dev = inode->i_sb->s_dev; | |
6670 | ino = inode->i_ino; | |
6671 | gen = inode->i_generation; | |
6672 | maj = MAJOR(dev); | |
6673 | min = MINOR(dev); | |
f972eb63 | 6674 | |
c7e548b4 | 6675 | goto got_name; |
0a4a9391 | 6676 | } else { |
fbe26abe JO |
6677 | if (vma->vm_ops && vma->vm_ops->name) { |
6678 | name = (char *) vma->vm_ops->name(vma); | |
6679 | if (name) | |
6680 | goto cpy_name; | |
6681 | } | |
6682 | ||
2c42cfbf | 6683 | name = (char *)arch_vma_name(vma); |
c7e548b4 ON |
6684 | if (name) |
6685 | goto cpy_name; | |
089dd79d | 6686 | |
32c5fb7e | 6687 | if (vma->vm_start <= vma->vm_mm->start_brk && |
3af9e859 | 6688 | vma->vm_end >= vma->vm_mm->brk) { |
c7e548b4 ON |
6689 | name = "[heap]"; |
6690 | goto cpy_name; | |
32c5fb7e ON |
6691 | } |
6692 | if (vma->vm_start <= vma->vm_mm->start_stack && | |
3af9e859 | 6693 | vma->vm_end >= vma->vm_mm->start_stack) { |
c7e548b4 ON |
6694 | name = "[stack]"; |
6695 | goto cpy_name; | |
089dd79d PZ |
6696 | } |
6697 | ||
c7e548b4 ON |
6698 | name = "//anon"; |
6699 | goto cpy_name; | |
0a4a9391 PZ |
6700 | } |
6701 | ||
c7e548b4 ON |
6702 | cpy_name: |
6703 | strlcpy(tmp, name, sizeof(tmp)); | |
6704 | name = tmp; | |
0a4a9391 | 6705 | got_name: |
2c42cfbf PZ |
6706 | /* |
6707 | * Since our buffer works in 8 byte units we need to align our string | |
6708 | * size to a multiple of 8. However, we must guarantee the tail end is | |
6709 | * zero'd out to avoid leaking random bits to userspace. | |
6710 | */ | |
6711 | size = strlen(name)+1; | |
6712 | while (!IS_ALIGNED(size, sizeof(u64))) | |
6713 | name[size++] = '\0'; | |
0a4a9391 PZ |
6714 | |
6715 | mmap_event->file_name = name; | |
6716 | mmap_event->file_size = size; | |
13d7a241 SE |
6717 | mmap_event->maj = maj; |
6718 | mmap_event->min = min; | |
6719 | mmap_event->ino = ino; | |
6720 | mmap_event->ino_generation = gen; | |
f972eb63 PZ |
6721 | mmap_event->prot = prot; |
6722 | mmap_event->flags = flags; | |
0a4a9391 | 6723 | |
2fe85427 SE |
6724 | if (!(vma->vm_flags & VM_EXEC)) |
6725 | mmap_event->event_id.header.misc |= PERF_RECORD_MISC_MMAP_DATA; | |
6726 | ||
cdd6c482 | 6727 | mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size; |
0a4a9391 | 6728 | |
aab5b71e | 6729 | perf_iterate_sb(perf_event_mmap_output, |
52d857a8 JO |
6730 | mmap_event, |
6731 | NULL); | |
665c2142 | 6732 | |
0a4a9391 PZ |
6733 | kfree(buf); |
6734 | } | |
6735 | ||
375637bc AS |
6736 | /* |
6737 | * Check whether inode and address range match filter criteria. | |
6738 | */ | |
6739 | static bool perf_addr_filter_match(struct perf_addr_filter *filter, | |
6740 | struct file *file, unsigned long offset, | |
6741 | unsigned long size) | |
6742 | { | |
45063097 | 6743 | if (filter->inode != file_inode(file)) |
375637bc AS |
6744 | return false; |
6745 | ||
6746 | if (filter->offset > offset + size) | |
6747 | return false; | |
6748 | ||
6749 | if (filter->offset + filter->size < offset) | |
6750 | return false; | |
6751 | ||
6752 | return true; | |
6753 | } | |
6754 | ||
6755 | static void __perf_addr_filters_adjust(struct perf_event *event, void *data) | |
6756 | { | |
6757 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
6758 | struct vm_area_struct *vma = data; | |
6759 | unsigned long off = vma->vm_pgoff << PAGE_SHIFT, flags; | |
6760 | struct file *file = vma->vm_file; | |
6761 | struct perf_addr_filter *filter; | |
6762 | unsigned int restart = 0, count = 0; | |
6763 | ||
6764 | if (!has_addr_filter(event)) | |
6765 | return; | |
6766 | ||
6767 | if (!file) | |
6768 | return; | |
6769 | ||
6770 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
6771 | list_for_each_entry(filter, &ifh->list, entry) { | |
6772 | if (perf_addr_filter_match(filter, file, off, | |
6773 | vma->vm_end - vma->vm_start)) { | |
6774 | event->addr_filters_offs[count] = vma->vm_start; | |
6775 | restart++; | |
6776 | } | |
6777 | ||
6778 | count++; | |
6779 | } | |
6780 | ||
6781 | if (restart) | |
6782 | event->addr_filters_gen++; | |
6783 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
6784 | ||
6785 | if (restart) | |
767ae086 | 6786 | perf_event_stop(event, 1); |
375637bc AS |
6787 | } |
6788 | ||
6789 | /* | |
6790 | * Adjust all task's events' filters to the new vma | |
6791 | */ | |
6792 | static void perf_addr_filters_adjust(struct vm_area_struct *vma) | |
6793 | { | |
6794 | struct perf_event_context *ctx; | |
6795 | int ctxn; | |
6796 | ||
12b40a23 MP |
6797 | /* |
6798 | * Data tracing isn't supported yet and as such there is no need | |
6799 | * to keep track of anything that isn't related to executable code: | |
6800 | */ | |
6801 | if (!(vma->vm_flags & VM_EXEC)) | |
6802 | return; | |
6803 | ||
375637bc AS |
6804 | rcu_read_lock(); |
6805 | for_each_task_context_nr(ctxn) { | |
6806 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); | |
6807 | if (!ctx) | |
6808 | continue; | |
6809 | ||
aab5b71e | 6810 | perf_iterate_ctx(ctx, __perf_addr_filters_adjust, vma, true); |
375637bc AS |
6811 | } |
6812 | rcu_read_unlock(); | |
6813 | } | |
6814 | ||
3af9e859 | 6815 | void perf_event_mmap(struct vm_area_struct *vma) |
0a4a9391 | 6816 | { |
9ee318a7 PZ |
6817 | struct perf_mmap_event mmap_event; |
6818 | ||
cdd6c482 | 6819 | if (!atomic_read(&nr_mmap_events)) |
9ee318a7 PZ |
6820 | return; |
6821 | ||
6822 | mmap_event = (struct perf_mmap_event){ | |
089dd79d | 6823 | .vma = vma, |
573402db PZ |
6824 | /* .file_name */ |
6825 | /* .file_size */ | |
cdd6c482 | 6826 | .event_id = { |
573402db | 6827 | .header = { |
cdd6c482 | 6828 | .type = PERF_RECORD_MMAP, |
39447b38 | 6829 | .misc = PERF_RECORD_MISC_USER, |
573402db PZ |
6830 | /* .size */ |
6831 | }, | |
6832 | /* .pid */ | |
6833 | /* .tid */ | |
089dd79d PZ |
6834 | .start = vma->vm_start, |
6835 | .len = vma->vm_end - vma->vm_start, | |
3a0304e9 | 6836 | .pgoff = (u64)vma->vm_pgoff << PAGE_SHIFT, |
0a4a9391 | 6837 | }, |
13d7a241 SE |
6838 | /* .maj (attr_mmap2 only) */ |
6839 | /* .min (attr_mmap2 only) */ | |
6840 | /* .ino (attr_mmap2 only) */ | |
6841 | /* .ino_generation (attr_mmap2 only) */ | |
f972eb63 PZ |
6842 | /* .prot (attr_mmap2 only) */ |
6843 | /* .flags (attr_mmap2 only) */ | |
0a4a9391 PZ |
6844 | }; |
6845 | ||
375637bc | 6846 | perf_addr_filters_adjust(vma); |
cdd6c482 | 6847 | perf_event_mmap_event(&mmap_event); |
0a4a9391 PZ |
6848 | } |
6849 | ||
68db7e98 AS |
6850 | void perf_event_aux_event(struct perf_event *event, unsigned long head, |
6851 | unsigned long size, u64 flags) | |
6852 | { | |
6853 | struct perf_output_handle handle; | |
6854 | struct perf_sample_data sample; | |
6855 | struct perf_aux_event { | |
6856 | struct perf_event_header header; | |
6857 | u64 offset; | |
6858 | u64 size; | |
6859 | u64 flags; | |
6860 | } rec = { | |
6861 | .header = { | |
6862 | .type = PERF_RECORD_AUX, | |
6863 | .misc = 0, | |
6864 | .size = sizeof(rec), | |
6865 | }, | |
6866 | .offset = head, | |
6867 | .size = size, | |
6868 | .flags = flags, | |
6869 | }; | |
6870 | int ret; | |
6871 | ||
6872 | perf_event_header__init_id(&rec.header, &sample, event); | |
6873 | ret = perf_output_begin(&handle, event, rec.header.size); | |
6874 | ||
6875 | if (ret) | |
6876 | return; | |
6877 | ||
6878 | perf_output_put(&handle, rec); | |
6879 | perf_event__output_id_sample(event, &handle, &sample); | |
6880 | ||
6881 | perf_output_end(&handle); | |
6882 | } | |
6883 | ||
f38b0dbb KL |
6884 | /* |
6885 | * Lost/dropped samples logging | |
6886 | */ | |
6887 | void perf_log_lost_samples(struct perf_event *event, u64 lost) | |
6888 | { | |
6889 | struct perf_output_handle handle; | |
6890 | struct perf_sample_data sample; | |
6891 | int ret; | |
6892 | ||
6893 | struct { | |
6894 | struct perf_event_header header; | |
6895 | u64 lost; | |
6896 | } lost_samples_event = { | |
6897 | .header = { | |
6898 | .type = PERF_RECORD_LOST_SAMPLES, | |
6899 | .misc = 0, | |
6900 | .size = sizeof(lost_samples_event), | |
6901 | }, | |
6902 | .lost = lost, | |
6903 | }; | |
6904 | ||
6905 | perf_event_header__init_id(&lost_samples_event.header, &sample, event); | |
6906 | ||
6907 | ret = perf_output_begin(&handle, event, | |
6908 | lost_samples_event.header.size); | |
6909 | if (ret) | |
6910 | return; | |
6911 | ||
6912 | perf_output_put(&handle, lost_samples_event); | |
6913 | perf_event__output_id_sample(event, &handle, &sample); | |
6914 | perf_output_end(&handle); | |
6915 | } | |
6916 | ||
45ac1403 AH |
6917 | /* |
6918 | * context_switch tracking | |
6919 | */ | |
6920 | ||
6921 | struct perf_switch_event { | |
6922 | struct task_struct *task; | |
6923 | struct task_struct *next_prev; | |
6924 | ||
6925 | struct { | |
6926 | struct perf_event_header header; | |
6927 | u32 next_prev_pid; | |
6928 | u32 next_prev_tid; | |
6929 | } event_id; | |
6930 | }; | |
6931 | ||
6932 | static int perf_event_switch_match(struct perf_event *event) | |
6933 | { | |
6934 | return event->attr.context_switch; | |
6935 | } | |
6936 | ||
6937 | static void perf_event_switch_output(struct perf_event *event, void *data) | |
6938 | { | |
6939 | struct perf_switch_event *se = data; | |
6940 | struct perf_output_handle handle; | |
6941 | struct perf_sample_data sample; | |
6942 | int ret; | |
6943 | ||
6944 | if (!perf_event_switch_match(event)) | |
6945 | return; | |
6946 | ||
6947 | /* Only CPU-wide events are allowed to see next/prev pid/tid */ | |
6948 | if (event->ctx->task) { | |
6949 | se->event_id.header.type = PERF_RECORD_SWITCH; | |
6950 | se->event_id.header.size = sizeof(se->event_id.header); | |
6951 | } else { | |
6952 | se->event_id.header.type = PERF_RECORD_SWITCH_CPU_WIDE; | |
6953 | se->event_id.header.size = sizeof(se->event_id); | |
6954 | se->event_id.next_prev_pid = | |
6955 | perf_event_pid(event, se->next_prev); | |
6956 | se->event_id.next_prev_tid = | |
6957 | perf_event_tid(event, se->next_prev); | |
6958 | } | |
6959 | ||
6960 | perf_event_header__init_id(&se->event_id.header, &sample, event); | |
6961 | ||
6962 | ret = perf_output_begin(&handle, event, se->event_id.header.size); | |
6963 | if (ret) | |
6964 | return; | |
6965 | ||
6966 | if (event->ctx->task) | |
6967 | perf_output_put(&handle, se->event_id.header); | |
6968 | else | |
6969 | perf_output_put(&handle, se->event_id); | |
6970 | ||
6971 | perf_event__output_id_sample(event, &handle, &sample); | |
6972 | ||
6973 | perf_output_end(&handle); | |
6974 | } | |
6975 | ||
6976 | static void perf_event_switch(struct task_struct *task, | |
6977 | struct task_struct *next_prev, bool sched_in) | |
6978 | { | |
6979 | struct perf_switch_event switch_event; | |
6980 | ||
6981 | /* N.B. caller checks nr_switch_events != 0 */ | |
6982 | ||
6983 | switch_event = (struct perf_switch_event){ | |
6984 | .task = task, | |
6985 | .next_prev = next_prev, | |
6986 | .event_id = { | |
6987 | .header = { | |
6988 | /* .type */ | |
6989 | .misc = sched_in ? 0 : PERF_RECORD_MISC_SWITCH_OUT, | |
6990 | /* .size */ | |
6991 | }, | |
6992 | /* .next_prev_pid */ | |
6993 | /* .next_prev_tid */ | |
6994 | }, | |
6995 | }; | |
6996 | ||
aab5b71e | 6997 | perf_iterate_sb(perf_event_switch_output, |
45ac1403 AH |
6998 | &switch_event, |
6999 | NULL); | |
7000 | } | |
7001 | ||
a78ac325 PZ |
7002 | /* |
7003 | * IRQ throttle logging | |
7004 | */ | |
7005 | ||
cdd6c482 | 7006 | static void perf_log_throttle(struct perf_event *event, int enable) |
a78ac325 PZ |
7007 | { |
7008 | struct perf_output_handle handle; | |
c980d109 | 7009 | struct perf_sample_data sample; |
a78ac325 PZ |
7010 | int ret; |
7011 | ||
7012 | struct { | |
7013 | struct perf_event_header header; | |
7014 | u64 time; | |
cca3f454 | 7015 | u64 id; |
7f453c24 | 7016 | u64 stream_id; |
a78ac325 PZ |
7017 | } throttle_event = { |
7018 | .header = { | |
cdd6c482 | 7019 | .type = PERF_RECORD_THROTTLE, |
a78ac325 PZ |
7020 | .misc = 0, |
7021 | .size = sizeof(throttle_event), | |
7022 | }, | |
34f43927 | 7023 | .time = perf_event_clock(event), |
cdd6c482 IM |
7024 | .id = primary_event_id(event), |
7025 | .stream_id = event->id, | |
a78ac325 PZ |
7026 | }; |
7027 | ||
966ee4d6 | 7028 | if (enable) |
cdd6c482 | 7029 | throttle_event.header.type = PERF_RECORD_UNTHROTTLE; |
966ee4d6 | 7030 | |
c980d109 ACM |
7031 | perf_event_header__init_id(&throttle_event.header, &sample, event); |
7032 | ||
7033 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 7034 | throttle_event.header.size); |
a78ac325 PZ |
7035 | if (ret) |
7036 | return; | |
7037 | ||
7038 | perf_output_put(&handle, throttle_event); | |
c980d109 | 7039 | perf_event__output_id_sample(event, &handle, &sample); |
a78ac325 PZ |
7040 | perf_output_end(&handle); |
7041 | } | |
7042 | ||
ec0d7729 AS |
7043 | static void perf_log_itrace_start(struct perf_event *event) |
7044 | { | |
7045 | struct perf_output_handle handle; | |
7046 | struct perf_sample_data sample; | |
7047 | struct perf_aux_event { | |
7048 | struct perf_event_header header; | |
7049 | u32 pid; | |
7050 | u32 tid; | |
7051 | } rec; | |
7052 | int ret; | |
7053 | ||
7054 | if (event->parent) | |
7055 | event = event->parent; | |
7056 | ||
7057 | if (!(event->pmu->capabilities & PERF_PMU_CAP_ITRACE) || | |
7058 | event->hw.itrace_started) | |
7059 | return; | |
7060 | ||
ec0d7729 AS |
7061 | rec.header.type = PERF_RECORD_ITRACE_START; |
7062 | rec.header.misc = 0; | |
7063 | rec.header.size = sizeof(rec); | |
7064 | rec.pid = perf_event_pid(event, current); | |
7065 | rec.tid = perf_event_tid(event, current); | |
7066 | ||
7067 | perf_event_header__init_id(&rec.header, &sample, event); | |
7068 | ret = perf_output_begin(&handle, event, rec.header.size); | |
7069 | ||
7070 | if (ret) | |
7071 | return; | |
7072 | ||
7073 | perf_output_put(&handle, rec); | |
7074 | perf_event__output_id_sample(event, &handle, &sample); | |
7075 | ||
7076 | perf_output_end(&handle); | |
7077 | } | |
7078 | ||
475113d9 JO |
7079 | static int |
7080 | __perf_event_account_interrupt(struct perf_event *event, int throttle) | |
f6c7d5fe | 7081 | { |
cdd6c482 | 7082 | struct hw_perf_event *hwc = &event->hw; |
79f14641 | 7083 | int ret = 0; |
475113d9 | 7084 | u64 seq; |
96398826 | 7085 | |
e050e3f0 SE |
7086 | seq = __this_cpu_read(perf_throttled_seq); |
7087 | if (seq != hwc->interrupts_seq) { | |
7088 | hwc->interrupts_seq = seq; | |
7089 | hwc->interrupts = 1; | |
7090 | } else { | |
7091 | hwc->interrupts++; | |
7092 | if (unlikely(throttle | |
7093 | && hwc->interrupts >= max_samples_per_tick)) { | |
7094 | __this_cpu_inc(perf_throttled_count); | |
555e0c1e | 7095 | tick_dep_set_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
163ec435 PZ |
7096 | hwc->interrupts = MAX_INTERRUPTS; |
7097 | perf_log_throttle(event, 0); | |
a78ac325 PZ |
7098 | ret = 1; |
7099 | } | |
e050e3f0 | 7100 | } |
60db5e09 | 7101 | |
cdd6c482 | 7102 | if (event->attr.freq) { |
def0a9b2 | 7103 | u64 now = perf_clock(); |
abd50713 | 7104 | s64 delta = now - hwc->freq_time_stamp; |
bd2b5b12 | 7105 | |
abd50713 | 7106 | hwc->freq_time_stamp = now; |
bd2b5b12 | 7107 | |
abd50713 | 7108 | if (delta > 0 && delta < 2*TICK_NSEC) |
f39d47ff | 7109 | perf_adjust_period(event, delta, hwc->last_period, true); |
bd2b5b12 PZ |
7110 | } |
7111 | ||
475113d9 JO |
7112 | return ret; |
7113 | } | |
7114 | ||
7115 | int perf_event_account_interrupt(struct perf_event *event) | |
7116 | { | |
7117 | return __perf_event_account_interrupt(event, 1); | |
7118 | } | |
7119 | ||
7120 | /* | |
7121 | * Generic event overflow handling, sampling. | |
7122 | */ | |
7123 | ||
7124 | static int __perf_event_overflow(struct perf_event *event, | |
7125 | int throttle, struct perf_sample_data *data, | |
7126 | struct pt_regs *regs) | |
7127 | { | |
7128 | int events = atomic_read(&event->event_limit); | |
7129 | int ret = 0; | |
7130 | ||
7131 | /* | |
7132 | * Non-sampling counters might still use the PMI to fold short | |
7133 | * hardware counters, ignore those. | |
7134 | */ | |
7135 | if (unlikely(!is_sampling_event(event))) | |
7136 | return 0; | |
7137 | ||
7138 | ret = __perf_event_account_interrupt(event, throttle); | |
7139 | ||
2023b359 PZ |
7140 | /* |
7141 | * XXX event_limit might not quite work as expected on inherited | |
cdd6c482 | 7142 | * events |
2023b359 PZ |
7143 | */ |
7144 | ||
cdd6c482 IM |
7145 | event->pending_kill = POLL_IN; |
7146 | if (events && atomic_dec_and_test(&event->event_limit)) { | |
79f14641 | 7147 | ret = 1; |
cdd6c482 | 7148 | event->pending_kill = POLL_HUP; |
5aab90ce JO |
7149 | |
7150 | perf_event_disable_inatomic(event); | |
79f14641 PZ |
7151 | } |
7152 | ||
aa6a5f3c | 7153 | READ_ONCE(event->overflow_handler)(event, data, regs); |
453f19ee | 7154 | |
fed66e2c | 7155 | if (*perf_event_fasync(event) && event->pending_kill) { |
a8b0ca17 PZ |
7156 | event->pending_wakeup = 1; |
7157 | irq_work_queue(&event->pending); | |
f506b3dc PZ |
7158 | } |
7159 | ||
79f14641 | 7160 | return ret; |
f6c7d5fe PZ |
7161 | } |
7162 | ||
a8b0ca17 | 7163 | int perf_event_overflow(struct perf_event *event, |
5622f295 MM |
7164 | struct perf_sample_data *data, |
7165 | struct pt_regs *regs) | |
850bc73f | 7166 | { |
a8b0ca17 | 7167 | return __perf_event_overflow(event, 1, data, regs); |
850bc73f PZ |
7168 | } |
7169 | ||
15dbf27c | 7170 | /* |
cdd6c482 | 7171 | * Generic software event infrastructure |
15dbf27c PZ |
7172 | */ |
7173 | ||
b28ab83c PZ |
7174 | struct swevent_htable { |
7175 | struct swevent_hlist *swevent_hlist; | |
7176 | struct mutex hlist_mutex; | |
7177 | int hlist_refcount; | |
7178 | ||
7179 | /* Recursion avoidance in each contexts */ | |
7180 | int recursion[PERF_NR_CONTEXTS]; | |
7181 | }; | |
7182 | ||
7183 | static DEFINE_PER_CPU(struct swevent_htable, swevent_htable); | |
7184 | ||
7b4b6658 | 7185 | /* |
cdd6c482 IM |
7186 | * We directly increment event->count and keep a second value in |
7187 | * event->hw.period_left to count intervals. This period event | |
7b4b6658 PZ |
7188 | * is kept in the range [-sample_period, 0] so that we can use the |
7189 | * sign as trigger. | |
7190 | */ | |
7191 | ||
ab573844 | 7192 | u64 perf_swevent_set_period(struct perf_event *event) |
15dbf27c | 7193 | { |
cdd6c482 | 7194 | struct hw_perf_event *hwc = &event->hw; |
7b4b6658 PZ |
7195 | u64 period = hwc->last_period; |
7196 | u64 nr, offset; | |
7197 | s64 old, val; | |
7198 | ||
7199 | hwc->last_period = hwc->sample_period; | |
15dbf27c PZ |
7200 | |
7201 | again: | |
e7850595 | 7202 | old = val = local64_read(&hwc->period_left); |
7b4b6658 PZ |
7203 | if (val < 0) |
7204 | return 0; | |
15dbf27c | 7205 | |
7b4b6658 PZ |
7206 | nr = div64_u64(period + val, period); |
7207 | offset = nr * period; | |
7208 | val -= offset; | |
e7850595 | 7209 | if (local64_cmpxchg(&hwc->period_left, old, val) != old) |
7b4b6658 | 7210 | goto again; |
15dbf27c | 7211 | |
7b4b6658 | 7212 | return nr; |
15dbf27c PZ |
7213 | } |
7214 | ||
0cff784a | 7215 | static void perf_swevent_overflow(struct perf_event *event, u64 overflow, |
a8b0ca17 | 7216 | struct perf_sample_data *data, |
5622f295 | 7217 | struct pt_regs *regs) |
15dbf27c | 7218 | { |
cdd6c482 | 7219 | struct hw_perf_event *hwc = &event->hw; |
850bc73f | 7220 | int throttle = 0; |
15dbf27c | 7221 | |
0cff784a PZ |
7222 | if (!overflow) |
7223 | overflow = perf_swevent_set_period(event); | |
15dbf27c | 7224 | |
7b4b6658 PZ |
7225 | if (hwc->interrupts == MAX_INTERRUPTS) |
7226 | return; | |
15dbf27c | 7227 | |
7b4b6658 | 7228 | for (; overflow; overflow--) { |
a8b0ca17 | 7229 | if (__perf_event_overflow(event, throttle, |
5622f295 | 7230 | data, regs)) { |
7b4b6658 PZ |
7231 | /* |
7232 | * We inhibit the overflow from happening when | |
7233 | * hwc->interrupts == MAX_INTERRUPTS. | |
7234 | */ | |
7235 | break; | |
7236 | } | |
cf450a73 | 7237 | throttle = 1; |
7b4b6658 | 7238 | } |
15dbf27c PZ |
7239 | } |
7240 | ||
a4eaf7f1 | 7241 | static void perf_swevent_event(struct perf_event *event, u64 nr, |
a8b0ca17 | 7242 | struct perf_sample_data *data, |
5622f295 | 7243 | struct pt_regs *regs) |
7b4b6658 | 7244 | { |
cdd6c482 | 7245 | struct hw_perf_event *hwc = &event->hw; |
d6d020e9 | 7246 | |
e7850595 | 7247 | local64_add(nr, &event->count); |
d6d020e9 | 7248 | |
0cff784a PZ |
7249 | if (!regs) |
7250 | return; | |
7251 | ||
6c7e550f | 7252 | if (!is_sampling_event(event)) |
7b4b6658 | 7253 | return; |
d6d020e9 | 7254 | |
5d81e5cf AV |
7255 | if ((event->attr.sample_type & PERF_SAMPLE_PERIOD) && !event->attr.freq) { |
7256 | data->period = nr; | |
7257 | return perf_swevent_overflow(event, 1, data, regs); | |
7258 | } else | |
7259 | data->period = event->hw.last_period; | |
7260 | ||
0cff784a | 7261 | if (nr == 1 && hwc->sample_period == 1 && !event->attr.freq) |
a8b0ca17 | 7262 | return perf_swevent_overflow(event, 1, data, regs); |
0cff784a | 7263 | |
e7850595 | 7264 | if (local64_add_negative(nr, &hwc->period_left)) |
7b4b6658 | 7265 | return; |
df1a132b | 7266 | |
a8b0ca17 | 7267 | perf_swevent_overflow(event, 0, data, regs); |
d6d020e9 PZ |
7268 | } |
7269 | ||
f5ffe02e FW |
7270 | static int perf_exclude_event(struct perf_event *event, |
7271 | struct pt_regs *regs) | |
7272 | { | |
a4eaf7f1 | 7273 | if (event->hw.state & PERF_HES_STOPPED) |
91b2f482 | 7274 | return 1; |
a4eaf7f1 | 7275 | |
f5ffe02e FW |
7276 | if (regs) { |
7277 | if (event->attr.exclude_user && user_mode(regs)) | |
7278 | return 1; | |
7279 | ||
7280 | if (event->attr.exclude_kernel && !user_mode(regs)) | |
7281 | return 1; | |
7282 | } | |
7283 | ||
7284 | return 0; | |
7285 | } | |
7286 | ||
cdd6c482 | 7287 | static int perf_swevent_match(struct perf_event *event, |
1c432d89 | 7288 | enum perf_type_id type, |
6fb2915d LZ |
7289 | u32 event_id, |
7290 | struct perf_sample_data *data, | |
7291 | struct pt_regs *regs) | |
15dbf27c | 7292 | { |
cdd6c482 | 7293 | if (event->attr.type != type) |
a21ca2ca | 7294 | return 0; |
f5ffe02e | 7295 | |
cdd6c482 | 7296 | if (event->attr.config != event_id) |
15dbf27c PZ |
7297 | return 0; |
7298 | ||
f5ffe02e FW |
7299 | if (perf_exclude_event(event, regs)) |
7300 | return 0; | |
15dbf27c PZ |
7301 | |
7302 | return 1; | |
7303 | } | |
7304 | ||
76e1d904 FW |
7305 | static inline u64 swevent_hash(u64 type, u32 event_id) |
7306 | { | |
7307 | u64 val = event_id | (type << 32); | |
7308 | ||
7309 | return hash_64(val, SWEVENT_HLIST_BITS); | |
7310 | } | |
7311 | ||
49f135ed FW |
7312 | static inline struct hlist_head * |
7313 | __find_swevent_head(struct swevent_hlist *hlist, u64 type, u32 event_id) | |
76e1d904 | 7314 | { |
49f135ed FW |
7315 | u64 hash = swevent_hash(type, event_id); |
7316 | ||
7317 | return &hlist->heads[hash]; | |
7318 | } | |
76e1d904 | 7319 | |
49f135ed FW |
7320 | /* For the read side: events when they trigger */ |
7321 | static inline struct hlist_head * | |
b28ab83c | 7322 | find_swevent_head_rcu(struct swevent_htable *swhash, u64 type, u32 event_id) |
49f135ed FW |
7323 | { |
7324 | struct swevent_hlist *hlist; | |
76e1d904 | 7325 | |
b28ab83c | 7326 | hlist = rcu_dereference(swhash->swevent_hlist); |
76e1d904 FW |
7327 | if (!hlist) |
7328 | return NULL; | |
7329 | ||
49f135ed FW |
7330 | return __find_swevent_head(hlist, type, event_id); |
7331 | } | |
7332 | ||
7333 | /* For the event head insertion and removal in the hlist */ | |
7334 | static inline struct hlist_head * | |
b28ab83c | 7335 | find_swevent_head(struct swevent_htable *swhash, struct perf_event *event) |
49f135ed FW |
7336 | { |
7337 | struct swevent_hlist *hlist; | |
7338 | u32 event_id = event->attr.config; | |
7339 | u64 type = event->attr.type; | |
7340 | ||
7341 | /* | |
7342 | * Event scheduling is always serialized against hlist allocation | |
7343 | * and release. Which makes the protected version suitable here. | |
7344 | * The context lock guarantees that. | |
7345 | */ | |
b28ab83c | 7346 | hlist = rcu_dereference_protected(swhash->swevent_hlist, |
49f135ed FW |
7347 | lockdep_is_held(&event->ctx->lock)); |
7348 | if (!hlist) | |
7349 | return NULL; | |
7350 | ||
7351 | return __find_swevent_head(hlist, type, event_id); | |
76e1d904 FW |
7352 | } |
7353 | ||
7354 | static void do_perf_sw_event(enum perf_type_id type, u32 event_id, | |
a8b0ca17 | 7355 | u64 nr, |
76e1d904 FW |
7356 | struct perf_sample_data *data, |
7357 | struct pt_regs *regs) | |
15dbf27c | 7358 | { |
4a32fea9 | 7359 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 7360 | struct perf_event *event; |
76e1d904 | 7361 | struct hlist_head *head; |
15dbf27c | 7362 | |
76e1d904 | 7363 | rcu_read_lock(); |
b28ab83c | 7364 | head = find_swevent_head_rcu(swhash, type, event_id); |
76e1d904 FW |
7365 | if (!head) |
7366 | goto end; | |
7367 | ||
b67bfe0d | 7368 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
6fb2915d | 7369 | if (perf_swevent_match(event, type, event_id, data, regs)) |
a8b0ca17 | 7370 | perf_swevent_event(event, nr, data, regs); |
15dbf27c | 7371 | } |
76e1d904 FW |
7372 | end: |
7373 | rcu_read_unlock(); | |
15dbf27c PZ |
7374 | } |
7375 | ||
86038c5e PZI |
7376 | DEFINE_PER_CPU(struct pt_regs, __perf_regs[4]); |
7377 | ||
4ed7c92d | 7378 | int perf_swevent_get_recursion_context(void) |
96f6d444 | 7379 | { |
4a32fea9 | 7380 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
96f6d444 | 7381 | |
b28ab83c | 7382 | return get_recursion_context(swhash->recursion); |
96f6d444 | 7383 | } |
645e8cc0 | 7384 | EXPORT_SYMBOL_GPL(perf_swevent_get_recursion_context); |
96f6d444 | 7385 | |
98b5c2c6 | 7386 | void perf_swevent_put_recursion_context(int rctx) |
15dbf27c | 7387 | { |
4a32fea9 | 7388 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
927c7a9e | 7389 | |
b28ab83c | 7390 | put_recursion_context(swhash->recursion, rctx); |
ce71b9df | 7391 | } |
15dbf27c | 7392 | |
86038c5e | 7393 | void ___perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) |
b8e83514 | 7394 | { |
a4234bfc | 7395 | struct perf_sample_data data; |
4ed7c92d | 7396 | |
86038c5e | 7397 | if (WARN_ON_ONCE(!regs)) |
4ed7c92d | 7398 | return; |
a4234bfc | 7399 | |
fd0d000b | 7400 | perf_sample_data_init(&data, addr, 0); |
a8b0ca17 | 7401 | do_perf_sw_event(PERF_TYPE_SOFTWARE, event_id, nr, &data, regs); |
86038c5e PZI |
7402 | } |
7403 | ||
7404 | void __perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) | |
7405 | { | |
7406 | int rctx; | |
7407 | ||
7408 | preempt_disable_notrace(); | |
7409 | rctx = perf_swevent_get_recursion_context(); | |
7410 | if (unlikely(rctx < 0)) | |
7411 | goto fail; | |
7412 | ||
7413 | ___perf_sw_event(event_id, nr, regs, addr); | |
4ed7c92d PZ |
7414 | |
7415 | perf_swevent_put_recursion_context(rctx); | |
86038c5e | 7416 | fail: |
1c024eca | 7417 | preempt_enable_notrace(); |
b8e83514 PZ |
7418 | } |
7419 | ||
cdd6c482 | 7420 | static void perf_swevent_read(struct perf_event *event) |
15dbf27c | 7421 | { |
15dbf27c PZ |
7422 | } |
7423 | ||
a4eaf7f1 | 7424 | static int perf_swevent_add(struct perf_event *event, int flags) |
15dbf27c | 7425 | { |
4a32fea9 | 7426 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 7427 | struct hw_perf_event *hwc = &event->hw; |
76e1d904 FW |
7428 | struct hlist_head *head; |
7429 | ||
6c7e550f | 7430 | if (is_sampling_event(event)) { |
7b4b6658 | 7431 | hwc->last_period = hwc->sample_period; |
cdd6c482 | 7432 | perf_swevent_set_period(event); |
7b4b6658 | 7433 | } |
76e1d904 | 7434 | |
a4eaf7f1 PZ |
7435 | hwc->state = !(flags & PERF_EF_START); |
7436 | ||
b28ab83c | 7437 | head = find_swevent_head(swhash, event); |
12ca6ad2 | 7438 | if (WARN_ON_ONCE(!head)) |
76e1d904 FW |
7439 | return -EINVAL; |
7440 | ||
7441 | hlist_add_head_rcu(&event->hlist_entry, head); | |
6a694a60 | 7442 | perf_event_update_userpage(event); |
76e1d904 | 7443 | |
15dbf27c PZ |
7444 | return 0; |
7445 | } | |
7446 | ||
a4eaf7f1 | 7447 | static void perf_swevent_del(struct perf_event *event, int flags) |
15dbf27c | 7448 | { |
76e1d904 | 7449 | hlist_del_rcu(&event->hlist_entry); |
15dbf27c PZ |
7450 | } |
7451 | ||
a4eaf7f1 | 7452 | static void perf_swevent_start(struct perf_event *event, int flags) |
5c92d124 | 7453 | { |
a4eaf7f1 | 7454 | event->hw.state = 0; |
d6d020e9 | 7455 | } |
aa9c4c0f | 7456 | |
a4eaf7f1 | 7457 | static void perf_swevent_stop(struct perf_event *event, int flags) |
d6d020e9 | 7458 | { |
a4eaf7f1 | 7459 | event->hw.state = PERF_HES_STOPPED; |
bae43c99 IM |
7460 | } |
7461 | ||
49f135ed FW |
7462 | /* Deref the hlist from the update side */ |
7463 | static inline struct swevent_hlist * | |
b28ab83c | 7464 | swevent_hlist_deref(struct swevent_htable *swhash) |
49f135ed | 7465 | { |
b28ab83c PZ |
7466 | return rcu_dereference_protected(swhash->swevent_hlist, |
7467 | lockdep_is_held(&swhash->hlist_mutex)); | |
49f135ed FW |
7468 | } |
7469 | ||
b28ab83c | 7470 | static void swevent_hlist_release(struct swevent_htable *swhash) |
76e1d904 | 7471 | { |
b28ab83c | 7472 | struct swevent_hlist *hlist = swevent_hlist_deref(swhash); |
76e1d904 | 7473 | |
49f135ed | 7474 | if (!hlist) |
76e1d904 FW |
7475 | return; |
7476 | ||
70691d4a | 7477 | RCU_INIT_POINTER(swhash->swevent_hlist, NULL); |
fa4bbc4c | 7478 | kfree_rcu(hlist, rcu_head); |
76e1d904 FW |
7479 | } |
7480 | ||
3b364d7b | 7481 | static void swevent_hlist_put_cpu(int cpu) |
76e1d904 | 7482 | { |
b28ab83c | 7483 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 | 7484 | |
b28ab83c | 7485 | mutex_lock(&swhash->hlist_mutex); |
76e1d904 | 7486 | |
b28ab83c PZ |
7487 | if (!--swhash->hlist_refcount) |
7488 | swevent_hlist_release(swhash); | |
76e1d904 | 7489 | |
b28ab83c | 7490 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
7491 | } |
7492 | ||
3b364d7b | 7493 | static void swevent_hlist_put(void) |
76e1d904 FW |
7494 | { |
7495 | int cpu; | |
7496 | ||
76e1d904 | 7497 | for_each_possible_cpu(cpu) |
3b364d7b | 7498 | swevent_hlist_put_cpu(cpu); |
76e1d904 FW |
7499 | } |
7500 | ||
3b364d7b | 7501 | static int swevent_hlist_get_cpu(int cpu) |
76e1d904 | 7502 | { |
b28ab83c | 7503 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 FW |
7504 | int err = 0; |
7505 | ||
b28ab83c | 7506 | mutex_lock(&swhash->hlist_mutex); |
b28ab83c | 7507 | if (!swevent_hlist_deref(swhash) && cpu_online(cpu)) { |
76e1d904 FW |
7508 | struct swevent_hlist *hlist; |
7509 | ||
7510 | hlist = kzalloc(sizeof(*hlist), GFP_KERNEL); | |
7511 | if (!hlist) { | |
7512 | err = -ENOMEM; | |
7513 | goto exit; | |
7514 | } | |
b28ab83c | 7515 | rcu_assign_pointer(swhash->swevent_hlist, hlist); |
76e1d904 | 7516 | } |
b28ab83c | 7517 | swhash->hlist_refcount++; |
9ed6060d | 7518 | exit: |
b28ab83c | 7519 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
7520 | |
7521 | return err; | |
7522 | } | |
7523 | ||
3b364d7b | 7524 | static int swevent_hlist_get(void) |
76e1d904 | 7525 | { |
3b364d7b | 7526 | int err, cpu, failed_cpu; |
76e1d904 | 7527 | |
76e1d904 FW |
7528 | get_online_cpus(); |
7529 | for_each_possible_cpu(cpu) { | |
3b364d7b | 7530 | err = swevent_hlist_get_cpu(cpu); |
76e1d904 FW |
7531 | if (err) { |
7532 | failed_cpu = cpu; | |
7533 | goto fail; | |
7534 | } | |
7535 | } | |
7536 | put_online_cpus(); | |
7537 | ||
7538 | return 0; | |
9ed6060d | 7539 | fail: |
76e1d904 FW |
7540 | for_each_possible_cpu(cpu) { |
7541 | if (cpu == failed_cpu) | |
7542 | break; | |
3b364d7b | 7543 | swevent_hlist_put_cpu(cpu); |
76e1d904 FW |
7544 | } |
7545 | ||
7546 | put_online_cpus(); | |
7547 | return err; | |
7548 | } | |
7549 | ||
c5905afb | 7550 | struct static_key perf_swevent_enabled[PERF_COUNT_SW_MAX]; |
95476b64 | 7551 | |
b0a873eb PZ |
7552 | static void sw_perf_event_destroy(struct perf_event *event) |
7553 | { | |
7554 | u64 event_id = event->attr.config; | |
95476b64 | 7555 | |
b0a873eb PZ |
7556 | WARN_ON(event->parent); |
7557 | ||
c5905afb | 7558 | static_key_slow_dec(&perf_swevent_enabled[event_id]); |
3b364d7b | 7559 | swevent_hlist_put(); |
b0a873eb PZ |
7560 | } |
7561 | ||
7562 | static int perf_swevent_init(struct perf_event *event) | |
7563 | { | |
8176cced | 7564 | u64 event_id = event->attr.config; |
b0a873eb PZ |
7565 | |
7566 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
7567 | return -ENOENT; | |
7568 | ||
2481c5fa SE |
7569 | /* |
7570 | * no branch sampling for software events | |
7571 | */ | |
7572 | if (has_branch_stack(event)) | |
7573 | return -EOPNOTSUPP; | |
7574 | ||
b0a873eb PZ |
7575 | switch (event_id) { |
7576 | case PERF_COUNT_SW_CPU_CLOCK: | |
7577 | case PERF_COUNT_SW_TASK_CLOCK: | |
7578 | return -ENOENT; | |
7579 | ||
7580 | default: | |
7581 | break; | |
7582 | } | |
7583 | ||
ce677831 | 7584 | if (event_id >= PERF_COUNT_SW_MAX) |
b0a873eb PZ |
7585 | return -ENOENT; |
7586 | ||
7587 | if (!event->parent) { | |
7588 | int err; | |
7589 | ||
3b364d7b | 7590 | err = swevent_hlist_get(); |
b0a873eb PZ |
7591 | if (err) |
7592 | return err; | |
7593 | ||
c5905afb | 7594 | static_key_slow_inc(&perf_swevent_enabled[event_id]); |
b0a873eb PZ |
7595 | event->destroy = sw_perf_event_destroy; |
7596 | } | |
7597 | ||
7598 | return 0; | |
7599 | } | |
7600 | ||
7601 | static struct pmu perf_swevent = { | |
89a1e187 | 7602 | .task_ctx_nr = perf_sw_context, |
95476b64 | 7603 | |
34f43927 PZ |
7604 | .capabilities = PERF_PMU_CAP_NO_NMI, |
7605 | ||
b0a873eb | 7606 | .event_init = perf_swevent_init, |
a4eaf7f1 PZ |
7607 | .add = perf_swevent_add, |
7608 | .del = perf_swevent_del, | |
7609 | .start = perf_swevent_start, | |
7610 | .stop = perf_swevent_stop, | |
1c024eca | 7611 | .read = perf_swevent_read, |
1c024eca PZ |
7612 | }; |
7613 | ||
b0a873eb PZ |
7614 | #ifdef CONFIG_EVENT_TRACING |
7615 | ||
1c024eca PZ |
7616 | static int perf_tp_filter_match(struct perf_event *event, |
7617 | struct perf_sample_data *data) | |
7618 | { | |
7e3f977e | 7619 | void *record = data->raw->frag.data; |
1c024eca | 7620 | |
b71b437e PZ |
7621 | /* only top level events have filters set */ |
7622 | if (event->parent) | |
7623 | event = event->parent; | |
7624 | ||
1c024eca PZ |
7625 | if (likely(!event->filter) || filter_match_preds(event->filter, record)) |
7626 | return 1; | |
7627 | return 0; | |
7628 | } | |
7629 | ||
7630 | static int perf_tp_event_match(struct perf_event *event, | |
7631 | struct perf_sample_data *data, | |
7632 | struct pt_regs *regs) | |
7633 | { | |
a0f7d0f7 FW |
7634 | if (event->hw.state & PERF_HES_STOPPED) |
7635 | return 0; | |
580d607c PZ |
7636 | /* |
7637 | * All tracepoints are from kernel-space. | |
7638 | */ | |
7639 | if (event->attr.exclude_kernel) | |
1c024eca PZ |
7640 | return 0; |
7641 | ||
7642 | if (!perf_tp_filter_match(event, data)) | |
7643 | return 0; | |
7644 | ||
7645 | return 1; | |
7646 | } | |
7647 | ||
85b67bcb AS |
7648 | void perf_trace_run_bpf_submit(void *raw_data, int size, int rctx, |
7649 | struct trace_event_call *call, u64 count, | |
7650 | struct pt_regs *regs, struct hlist_head *head, | |
7651 | struct task_struct *task) | |
7652 | { | |
7653 | struct bpf_prog *prog = call->prog; | |
7654 | ||
7655 | if (prog) { | |
7656 | *(struct pt_regs **)raw_data = regs; | |
7657 | if (!trace_call_bpf(prog, raw_data) || hlist_empty(head)) { | |
7658 | perf_swevent_put_recursion_context(rctx); | |
7659 | return; | |
7660 | } | |
7661 | } | |
7662 | perf_tp_event(call->event.type, count, raw_data, size, regs, head, | |
7663 | rctx, task); | |
7664 | } | |
7665 | EXPORT_SYMBOL_GPL(perf_trace_run_bpf_submit); | |
7666 | ||
1e1dcd93 | 7667 | void perf_tp_event(u16 event_type, u64 count, void *record, int entry_size, |
e6dab5ff AV |
7668 | struct pt_regs *regs, struct hlist_head *head, int rctx, |
7669 | struct task_struct *task) | |
95476b64 FW |
7670 | { |
7671 | struct perf_sample_data data; | |
1c024eca | 7672 | struct perf_event *event; |
1c024eca | 7673 | |
95476b64 | 7674 | struct perf_raw_record raw = { |
7e3f977e DB |
7675 | .frag = { |
7676 | .size = entry_size, | |
7677 | .data = record, | |
7678 | }, | |
95476b64 FW |
7679 | }; |
7680 | ||
1e1dcd93 | 7681 | perf_sample_data_init(&data, 0, 0); |
95476b64 FW |
7682 | data.raw = &raw; |
7683 | ||
1e1dcd93 AS |
7684 | perf_trace_buf_update(record, event_type); |
7685 | ||
b67bfe0d | 7686 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
1c024eca | 7687 | if (perf_tp_event_match(event, &data, regs)) |
a8b0ca17 | 7688 | perf_swevent_event(event, count, &data, regs); |
4f41c013 | 7689 | } |
ecc55f84 | 7690 | |
e6dab5ff AV |
7691 | /* |
7692 | * If we got specified a target task, also iterate its context and | |
7693 | * deliver this event there too. | |
7694 | */ | |
7695 | if (task && task != current) { | |
7696 | struct perf_event_context *ctx; | |
7697 | struct trace_entry *entry = record; | |
7698 | ||
7699 | rcu_read_lock(); | |
7700 | ctx = rcu_dereference(task->perf_event_ctxp[perf_sw_context]); | |
7701 | if (!ctx) | |
7702 | goto unlock; | |
7703 | ||
7704 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
7705 | if (event->attr.type != PERF_TYPE_TRACEPOINT) | |
7706 | continue; | |
7707 | if (event->attr.config != entry->type) | |
7708 | continue; | |
7709 | if (perf_tp_event_match(event, &data, regs)) | |
7710 | perf_swevent_event(event, count, &data, regs); | |
7711 | } | |
7712 | unlock: | |
7713 | rcu_read_unlock(); | |
7714 | } | |
7715 | ||
ecc55f84 | 7716 | perf_swevent_put_recursion_context(rctx); |
95476b64 FW |
7717 | } |
7718 | EXPORT_SYMBOL_GPL(perf_tp_event); | |
7719 | ||
cdd6c482 | 7720 | static void tp_perf_event_destroy(struct perf_event *event) |
e077df4f | 7721 | { |
1c024eca | 7722 | perf_trace_destroy(event); |
e077df4f PZ |
7723 | } |
7724 | ||
b0a873eb | 7725 | static int perf_tp_event_init(struct perf_event *event) |
e077df4f | 7726 | { |
76e1d904 FW |
7727 | int err; |
7728 | ||
b0a873eb PZ |
7729 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
7730 | return -ENOENT; | |
7731 | ||
2481c5fa SE |
7732 | /* |
7733 | * no branch sampling for tracepoint events | |
7734 | */ | |
7735 | if (has_branch_stack(event)) | |
7736 | return -EOPNOTSUPP; | |
7737 | ||
1c024eca PZ |
7738 | err = perf_trace_init(event); |
7739 | if (err) | |
b0a873eb | 7740 | return err; |
e077df4f | 7741 | |
cdd6c482 | 7742 | event->destroy = tp_perf_event_destroy; |
e077df4f | 7743 | |
b0a873eb PZ |
7744 | return 0; |
7745 | } | |
7746 | ||
7747 | static struct pmu perf_tracepoint = { | |
89a1e187 PZ |
7748 | .task_ctx_nr = perf_sw_context, |
7749 | ||
b0a873eb | 7750 | .event_init = perf_tp_event_init, |
a4eaf7f1 PZ |
7751 | .add = perf_trace_add, |
7752 | .del = perf_trace_del, | |
7753 | .start = perf_swevent_start, | |
7754 | .stop = perf_swevent_stop, | |
b0a873eb | 7755 | .read = perf_swevent_read, |
b0a873eb PZ |
7756 | }; |
7757 | ||
7758 | static inline void perf_tp_register(void) | |
7759 | { | |
2e80a82a | 7760 | perf_pmu_register(&perf_tracepoint, "tracepoint", PERF_TYPE_TRACEPOINT); |
e077df4f | 7761 | } |
6fb2915d | 7762 | |
6fb2915d LZ |
7763 | static void perf_event_free_filter(struct perf_event *event) |
7764 | { | |
7765 | ftrace_profile_free_filter(event); | |
7766 | } | |
7767 | ||
aa6a5f3c AS |
7768 | #ifdef CONFIG_BPF_SYSCALL |
7769 | static void bpf_overflow_handler(struct perf_event *event, | |
7770 | struct perf_sample_data *data, | |
7771 | struct pt_regs *regs) | |
7772 | { | |
7773 | struct bpf_perf_event_data_kern ctx = { | |
7774 | .data = data, | |
7775 | .regs = regs, | |
7776 | }; | |
7777 | int ret = 0; | |
7778 | ||
7779 | preempt_disable(); | |
7780 | if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) | |
7781 | goto out; | |
7782 | rcu_read_lock(); | |
88575199 | 7783 | ret = BPF_PROG_RUN(event->prog, &ctx); |
aa6a5f3c AS |
7784 | rcu_read_unlock(); |
7785 | out: | |
7786 | __this_cpu_dec(bpf_prog_active); | |
7787 | preempt_enable(); | |
7788 | if (!ret) | |
7789 | return; | |
7790 | ||
7791 | event->orig_overflow_handler(event, data, regs); | |
7792 | } | |
7793 | ||
7794 | static int perf_event_set_bpf_handler(struct perf_event *event, u32 prog_fd) | |
7795 | { | |
7796 | struct bpf_prog *prog; | |
7797 | ||
7798 | if (event->overflow_handler_context) | |
7799 | /* hw breakpoint or kernel counter */ | |
7800 | return -EINVAL; | |
7801 | ||
7802 | if (event->prog) | |
7803 | return -EEXIST; | |
7804 | ||
7805 | prog = bpf_prog_get_type(prog_fd, BPF_PROG_TYPE_PERF_EVENT); | |
7806 | if (IS_ERR(prog)) | |
7807 | return PTR_ERR(prog); | |
7808 | ||
7809 | event->prog = prog; | |
7810 | event->orig_overflow_handler = READ_ONCE(event->overflow_handler); | |
7811 | WRITE_ONCE(event->overflow_handler, bpf_overflow_handler); | |
7812 | return 0; | |
7813 | } | |
7814 | ||
7815 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
7816 | { | |
7817 | struct bpf_prog *prog = event->prog; | |
7818 | ||
7819 | if (!prog) | |
7820 | return; | |
7821 | ||
7822 | WRITE_ONCE(event->overflow_handler, event->orig_overflow_handler); | |
7823 | event->prog = NULL; | |
7824 | bpf_prog_put(prog); | |
7825 | } | |
7826 | #else | |
7827 | static int perf_event_set_bpf_handler(struct perf_event *event, u32 prog_fd) | |
7828 | { | |
7829 | return -EOPNOTSUPP; | |
7830 | } | |
7831 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
7832 | { | |
7833 | } | |
7834 | #endif | |
7835 | ||
2541517c AS |
7836 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
7837 | { | |
98b5c2c6 | 7838 | bool is_kprobe, is_tracepoint; |
2541517c AS |
7839 | struct bpf_prog *prog; |
7840 | ||
aa6a5f3c AS |
7841 | if (event->attr.type == PERF_TYPE_HARDWARE || |
7842 | event->attr.type == PERF_TYPE_SOFTWARE) | |
7843 | return perf_event_set_bpf_handler(event, prog_fd); | |
7844 | ||
2541517c AS |
7845 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
7846 | return -EINVAL; | |
7847 | ||
7848 | if (event->tp_event->prog) | |
7849 | return -EEXIST; | |
7850 | ||
98b5c2c6 AS |
7851 | is_kprobe = event->tp_event->flags & TRACE_EVENT_FL_UKPROBE; |
7852 | is_tracepoint = event->tp_event->flags & TRACE_EVENT_FL_TRACEPOINT; | |
7853 | if (!is_kprobe && !is_tracepoint) | |
7854 | /* bpf programs can only be attached to u/kprobe or tracepoint */ | |
2541517c AS |
7855 | return -EINVAL; |
7856 | ||
7857 | prog = bpf_prog_get(prog_fd); | |
7858 | if (IS_ERR(prog)) | |
7859 | return PTR_ERR(prog); | |
7860 | ||
98b5c2c6 AS |
7861 | if ((is_kprobe && prog->type != BPF_PROG_TYPE_KPROBE) || |
7862 | (is_tracepoint && prog->type != BPF_PROG_TYPE_TRACEPOINT)) { | |
2541517c AS |
7863 | /* valid fd, but invalid bpf program type */ |
7864 | bpf_prog_put(prog); | |
7865 | return -EINVAL; | |
7866 | } | |
7867 | ||
32bbe007 AS |
7868 | if (is_tracepoint) { |
7869 | int off = trace_event_get_offsets(event->tp_event); | |
7870 | ||
7871 | if (prog->aux->max_ctx_offset > off) { | |
7872 | bpf_prog_put(prog); | |
7873 | return -EACCES; | |
7874 | } | |
7875 | } | |
2541517c AS |
7876 | event->tp_event->prog = prog; |
7877 | ||
7878 | return 0; | |
7879 | } | |
7880 | ||
7881 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
7882 | { | |
7883 | struct bpf_prog *prog; | |
7884 | ||
aa6a5f3c AS |
7885 | perf_event_free_bpf_handler(event); |
7886 | ||
2541517c AS |
7887 | if (!event->tp_event) |
7888 | return; | |
7889 | ||
7890 | prog = event->tp_event->prog; | |
7891 | if (prog) { | |
7892 | event->tp_event->prog = NULL; | |
1aacde3d | 7893 | bpf_prog_put(prog); |
2541517c AS |
7894 | } |
7895 | } | |
7896 | ||
e077df4f | 7897 | #else |
6fb2915d | 7898 | |
b0a873eb | 7899 | static inline void perf_tp_register(void) |
e077df4f | 7900 | { |
e077df4f | 7901 | } |
6fb2915d | 7902 | |
6fb2915d LZ |
7903 | static void perf_event_free_filter(struct perf_event *event) |
7904 | { | |
7905 | } | |
7906 | ||
2541517c AS |
7907 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
7908 | { | |
7909 | return -ENOENT; | |
7910 | } | |
7911 | ||
7912 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
7913 | { | |
7914 | } | |
07b139c8 | 7915 | #endif /* CONFIG_EVENT_TRACING */ |
e077df4f | 7916 | |
24f1e32c | 7917 | #ifdef CONFIG_HAVE_HW_BREAKPOINT |
f5ffe02e | 7918 | void perf_bp_event(struct perf_event *bp, void *data) |
24f1e32c | 7919 | { |
f5ffe02e FW |
7920 | struct perf_sample_data sample; |
7921 | struct pt_regs *regs = data; | |
7922 | ||
fd0d000b | 7923 | perf_sample_data_init(&sample, bp->attr.bp_addr, 0); |
f5ffe02e | 7924 | |
a4eaf7f1 | 7925 | if (!bp->hw.state && !perf_exclude_event(bp, regs)) |
a8b0ca17 | 7926 | perf_swevent_event(bp, 1, &sample, regs); |
24f1e32c FW |
7927 | } |
7928 | #endif | |
7929 | ||
375637bc AS |
7930 | /* |
7931 | * Allocate a new address filter | |
7932 | */ | |
7933 | static struct perf_addr_filter * | |
7934 | perf_addr_filter_new(struct perf_event *event, struct list_head *filters) | |
7935 | { | |
7936 | int node = cpu_to_node(event->cpu == -1 ? 0 : event->cpu); | |
7937 | struct perf_addr_filter *filter; | |
7938 | ||
7939 | filter = kzalloc_node(sizeof(*filter), GFP_KERNEL, node); | |
7940 | if (!filter) | |
7941 | return NULL; | |
7942 | ||
7943 | INIT_LIST_HEAD(&filter->entry); | |
7944 | list_add_tail(&filter->entry, filters); | |
7945 | ||
7946 | return filter; | |
7947 | } | |
7948 | ||
7949 | static void free_filters_list(struct list_head *filters) | |
7950 | { | |
7951 | struct perf_addr_filter *filter, *iter; | |
7952 | ||
7953 | list_for_each_entry_safe(filter, iter, filters, entry) { | |
7954 | if (filter->inode) | |
7955 | iput(filter->inode); | |
7956 | list_del(&filter->entry); | |
7957 | kfree(filter); | |
7958 | } | |
7959 | } | |
7960 | ||
7961 | /* | |
7962 | * Free existing address filters and optionally install new ones | |
7963 | */ | |
7964 | static void perf_addr_filters_splice(struct perf_event *event, | |
7965 | struct list_head *head) | |
7966 | { | |
7967 | unsigned long flags; | |
7968 | LIST_HEAD(list); | |
7969 | ||
7970 | if (!has_addr_filter(event)) | |
7971 | return; | |
7972 | ||
7973 | /* don't bother with children, they don't have their own filters */ | |
7974 | if (event->parent) | |
7975 | return; | |
7976 | ||
7977 | raw_spin_lock_irqsave(&event->addr_filters.lock, flags); | |
7978 | ||
7979 | list_splice_init(&event->addr_filters.list, &list); | |
7980 | if (head) | |
7981 | list_splice(head, &event->addr_filters.list); | |
7982 | ||
7983 | raw_spin_unlock_irqrestore(&event->addr_filters.lock, flags); | |
7984 | ||
7985 | free_filters_list(&list); | |
7986 | } | |
7987 | ||
7988 | /* | |
7989 | * Scan through mm's vmas and see if one of them matches the | |
7990 | * @filter; if so, adjust filter's address range. | |
7991 | * Called with mm::mmap_sem down for reading. | |
7992 | */ | |
7993 | static unsigned long perf_addr_filter_apply(struct perf_addr_filter *filter, | |
7994 | struct mm_struct *mm) | |
7995 | { | |
7996 | struct vm_area_struct *vma; | |
7997 | ||
7998 | for (vma = mm->mmap; vma; vma = vma->vm_next) { | |
7999 | struct file *file = vma->vm_file; | |
8000 | unsigned long off = vma->vm_pgoff << PAGE_SHIFT; | |
8001 | unsigned long vma_size = vma->vm_end - vma->vm_start; | |
8002 | ||
8003 | if (!file) | |
8004 | continue; | |
8005 | ||
8006 | if (!perf_addr_filter_match(filter, file, off, vma_size)) | |
8007 | continue; | |
8008 | ||
8009 | return vma->vm_start; | |
8010 | } | |
8011 | ||
8012 | return 0; | |
8013 | } | |
8014 | ||
8015 | /* | |
8016 | * Update event's address range filters based on the | |
8017 | * task's existing mappings, if any. | |
8018 | */ | |
8019 | static void perf_event_addr_filters_apply(struct perf_event *event) | |
8020 | { | |
8021 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
8022 | struct task_struct *task = READ_ONCE(event->ctx->task); | |
8023 | struct perf_addr_filter *filter; | |
8024 | struct mm_struct *mm = NULL; | |
8025 | unsigned int count = 0; | |
8026 | unsigned long flags; | |
8027 | ||
8028 | /* | |
8029 | * We may observe TASK_TOMBSTONE, which means that the event tear-down | |
8030 | * will stop on the parent's child_mutex that our caller is also holding | |
8031 | */ | |
8032 | if (task == TASK_TOMBSTONE) | |
8033 | return; | |
8034 | ||
8035 | mm = get_task_mm(event->ctx->task); | |
8036 | if (!mm) | |
8037 | goto restart; | |
8038 | ||
8039 | down_read(&mm->mmap_sem); | |
8040 | ||
8041 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
8042 | list_for_each_entry(filter, &ifh->list, entry) { | |
8043 | event->addr_filters_offs[count] = 0; | |
8044 | ||
99f5bc9b MP |
8045 | /* |
8046 | * Adjust base offset if the filter is associated to a binary | |
8047 | * that needs to be mapped: | |
8048 | */ | |
8049 | if (filter->inode) | |
375637bc AS |
8050 | event->addr_filters_offs[count] = |
8051 | perf_addr_filter_apply(filter, mm); | |
8052 | ||
8053 | count++; | |
8054 | } | |
8055 | ||
8056 | event->addr_filters_gen++; | |
8057 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
8058 | ||
8059 | up_read(&mm->mmap_sem); | |
8060 | ||
8061 | mmput(mm); | |
8062 | ||
8063 | restart: | |
767ae086 | 8064 | perf_event_stop(event, 1); |
375637bc AS |
8065 | } |
8066 | ||
8067 | /* | |
8068 | * Address range filtering: limiting the data to certain | |
8069 | * instruction address ranges. Filters are ioctl()ed to us from | |
8070 | * userspace as ascii strings. | |
8071 | * | |
8072 | * Filter string format: | |
8073 | * | |
8074 | * ACTION RANGE_SPEC | |
8075 | * where ACTION is one of the | |
8076 | * * "filter": limit the trace to this region | |
8077 | * * "start": start tracing from this address | |
8078 | * * "stop": stop tracing at this address/region; | |
8079 | * RANGE_SPEC is | |
8080 | * * for kernel addresses: <start address>[/<size>] | |
8081 | * * for object files: <start address>[/<size>]@</path/to/object/file> | |
8082 | * | |
8083 | * if <size> is not specified, the range is treated as a single address. | |
8084 | */ | |
8085 | enum { | |
e96271f3 | 8086 | IF_ACT_NONE = -1, |
375637bc AS |
8087 | IF_ACT_FILTER, |
8088 | IF_ACT_START, | |
8089 | IF_ACT_STOP, | |
8090 | IF_SRC_FILE, | |
8091 | IF_SRC_KERNEL, | |
8092 | IF_SRC_FILEADDR, | |
8093 | IF_SRC_KERNELADDR, | |
8094 | }; | |
8095 | ||
8096 | enum { | |
8097 | IF_STATE_ACTION = 0, | |
8098 | IF_STATE_SOURCE, | |
8099 | IF_STATE_END, | |
8100 | }; | |
8101 | ||
8102 | static const match_table_t if_tokens = { | |
8103 | { IF_ACT_FILTER, "filter" }, | |
8104 | { IF_ACT_START, "start" }, | |
8105 | { IF_ACT_STOP, "stop" }, | |
8106 | { IF_SRC_FILE, "%u/%u@%s" }, | |
8107 | { IF_SRC_KERNEL, "%u/%u" }, | |
8108 | { IF_SRC_FILEADDR, "%u@%s" }, | |
8109 | { IF_SRC_KERNELADDR, "%u" }, | |
e96271f3 | 8110 | { IF_ACT_NONE, NULL }, |
375637bc AS |
8111 | }; |
8112 | ||
8113 | /* | |
8114 | * Address filter string parser | |
8115 | */ | |
8116 | static int | |
8117 | perf_event_parse_addr_filter(struct perf_event *event, char *fstr, | |
8118 | struct list_head *filters) | |
8119 | { | |
8120 | struct perf_addr_filter *filter = NULL; | |
8121 | char *start, *orig, *filename = NULL; | |
8122 | struct path path; | |
8123 | substring_t args[MAX_OPT_ARGS]; | |
8124 | int state = IF_STATE_ACTION, token; | |
8125 | unsigned int kernel = 0; | |
8126 | int ret = -EINVAL; | |
8127 | ||
8128 | orig = fstr = kstrdup(fstr, GFP_KERNEL); | |
8129 | if (!fstr) | |
8130 | return -ENOMEM; | |
8131 | ||
8132 | while ((start = strsep(&fstr, " ,\n")) != NULL) { | |
8133 | ret = -EINVAL; | |
8134 | ||
8135 | if (!*start) | |
8136 | continue; | |
8137 | ||
8138 | /* filter definition begins */ | |
8139 | if (state == IF_STATE_ACTION) { | |
8140 | filter = perf_addr_filter_new(event, filters); | |
8141 | if (!filter) | |
8142 | goto fail; | |
8143 | } | |
8144 | ||
8145 | token = match_token(start, if_tokens, args); | |
8146 | switch (token) { | |
8147 | case IF_ACT_FILTER: | |
8148 | case IF_ACT_START: | |
8149 | filter->filter = 1; | |
8150 | ||
8151 | case IF_ACT_STOP: | |
8152 | if (state != IF_STATE_ACTION) | |
8153 | goto fail; | |
8154 | ||
8155 | state = IF_STATE_SOURCE; | |
8156 | break; | |
8157 | ||
8158 | case IF_SRC_KERNELADDR: | |
8159 | case IF_SRC_KERNEL: | |
8160 | kernel = 1; | |
8161 | ||
8162 | case IF_SRC_FILEADDR: | |
8163 | case IF_SRC_FILE: | |
8164 | if (state != IF_STATE_SOURCE) | |
8165 | goto fail; | |
8166 | ||
8167 | if (token == IF_SRC_FILE || token == IF_SRC_KERNEL) | |
8168 | filter->range = 1; | |
8169 | ||
8170 | *args[0].to = 0; | |
8171 | ret = kstrtoul(args[0].from, 0, &filter->offset); | |
8172 | if (ret) | |
8173 | goto fail; | |
8174 | ||
8175 | if (filter->range) { | |
8176 | *args[1].to = 0; | |
8177 | ret = kstrtoul(args[1].from, 0, &filter->size); | |
8178 | if (ret) | |
8179 | goto fail; | |
8180 | } | |
8181 | ||
4059ffd0 MP |
8182 | if (token == IF_SRC_FILE || token == IF_SRC_FILEADDR) { |
8183 | int fpos = filter->range ? 2 : 1; | |
8184 | ||
8185 | filename = match_strdup(&args[fpos]); | |
375637bc AS |
8186 | if (!filename) { |
8187 | ret = -ENOMEM; | |
8188 | goto fail; | |
8189 | } | |
8190 | } | |
8191 | ||
8192 | state = IF_STATE_END; | |
8193 | break; | |
8194 | ||
8195 | default: | |
8196 | goto fail; | |
8197 | } | |
8198 | ||
8199 | /* | |
8200 | * Filter definition is fully parsed, validate and install it. | |
8201 | * Make sure that it doesn't contradict itself or the event's | |
8202 | * attribute. | |
8203 | */ | |
8204 | if (state == IF_STATE_END) { | |
8205 | if (kernel && event->attr.exclude_kernel) | |
8206 | goto fail; | |
8207 | ||
8208 | if (!kernel) { | |
8209 | if (!filename) | |
8210 | goto fail; | |
8211 | ||
8212 | /* look up the path and grab its inode */ | |
8213 | ret = kern_path(filename, LOOKUP_FOLLOW, &path); | |
8214 | if (ret) | |
8215 | goto fail_free_name; | |
8216 | ||
8217 | filter->inode = igrab(d_inode(path.dentry)); | |
8218 | path_put(&path); | |
8219 | kfree(filename); | |
8220 | filename = NULL; | |
8221 | ||
8222 | ret = -EINVAL; | |
8223 | if (!filter->inode || | |
8224 | !S_ISREG(filter->inode->i_mode)) | |
8225 | /* free_filters_list() will iput() */ | |
8226 | goto fail; | |
8227 | } | |
8228 | ||
8229 | /* ready to consume more filters */ | |
8230 | state = IF_STATE_ACTION; | |
8231 | filter = NULL; | |
8232 | } | |
8233 | } | |
8234 | ||
8235 | if (state != IF_STATE_ACTION) | |
8236 | goto fail; | |
8237 | ||
8238 | kfree(orig); | |
8239 | ||
8240 | return 0; | |
8241 | ||
8242 | fail_free_name: | |
8243 | kfree(filename); | |
8244 | fail: | |
8245 | free_filters_list(filters); | |
8246 | kfree(orig); | |
8247 | ||
8248 | return ret; | |
8249 | } | |
8250 | ||
8251 | static int | |
8252 | perf_event_set_addr_filter(struct perf_event *event, char *filter_str) | |
8253 | { | |
8254 | LIST_HEAD(filters); | |
8255 | int ret; | |
8256 | ||
8257 | /* | |
8258 | * Since this is called in perf_ioctl() path, we're already holding | |
8259 | * ctx::mutex. | |
8260 | */ | |
8261 | lockdep_assert_held(&event->ctx->mutex); | |
8262 | ||
8263 | if (WARN_ON_ONCE(event->parent)) | |
8264 | return -EINVAL; | |
8265 | ||
8266 | /* | |
8267 | * For now, we only support filtering in per-task events; doing so | |
8268 | * for CPU-wide events requires additional context switching trickery, | |
8269 | * since same object code will be mapped at different virtual | |
8270 | * addresses in different processes. | |
8271 | */ | |
8272 | if (!event->ctx->task) | |
8273 | return -EOPNOTSUPP; | |
8274 | ||
8275 | ret = perf_event_parse_addr_filter(event, filter_str, &filters); | |
8276 | if (ret) | |
8277 | return ret; | |
8278 | ||
8279 | ret = event->pmu->addr_filters_validate(&filters); | |
8280 | if (ret) { | |
8281 | free_filters_list(&filters); | |
8282 | return ret; | |
8283 | } | |
8284 | ||
8285 | /* remove existing filters, if any */ | |
8286 | perf_addr_filters_splice(event, &filters); | |
8287 | ||
8288 | /* install new filters */ | |
8289 | perf_event_for_each_child(event, perf_event_addr_filters_apply); | |
8290 | ||
8291 | return ret; | |
8292 | } | |
8293 | ||
c796bbbe AS |
8294 | static int perf_event_set_filter(struct perf_event *event, void __user *arg) |
8295 | { | |
8296 | char *filter_str; | |
8297 | int ret = -EINVAL; | |
8298 | ||
375637bc AS |
8299 | if ((event->attr.type != PERF_TYPE_TRACEPOINT || |
8300 | !IS_ENABLED(CONFIG_EVENT_TRACING)) && | |
8301 | !has_addr_filter(event)) | |
c796bbbe AS |
8302 | return -EINVAL; |
8303 | ||
8304 | filter_str = strndup_user(arg, PAGE_SIZE); | |
8305 | if (IS_ERR(filter_str)) | |
8306 | return PTR_ERR(filter_str); | |
8307 | ||
8308 | if (IS_ENABLED(CONFIG_EVENT_TRACING) && | |
8309 | event->attr.type == PERF_TYPE_TRACEPOINT) | |
8310 | ret = ftrace_profile_set_filter(event, event->attr.config, | |
8311 | filter_str); | |
375637bc AS |
8312 | else if (has_addr_filter(event)) |
8313 | ret = perf_event_set_addr_filter(event, filter_str); | |
c796bbbe AS |
8314 | |
8315 | kfree(filter_str); | |
8316 | return ret; | |
8317 | } | |
8318 | ||
b0a873eb PZ |
8319 | /* |
8320 | * hrtimer based swevent callback | |
8321 | */ | |
f29ac756 | 8322 | |
b0a873eb | 8323 | static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer) |
f29ac756 | 8324 | { |
b0a873eb PZ |
8325 | enum hrtimer_restart ret = HRTIMER_RESTART; |
8326 | struct perf_sample_data data; | |
8327 | struct pt_regs *regs; | |
8328 | struct perf_event *event; | |
8329 | u64 period; | |
f29ac756 | 8330 | |
b0a873eb | 8331 | event = container_of(hrtimer, struct perf_event, hw.hrtimer); |
ba3dd36c PZ |
8332 | |
8333 | if (event->state != PERF_EVENT_STATE_ACTIVE) | |
8334 | return HRTIMER_NORESTART; | |
8335 | ||
b0a873eb | 8336 | event->pmu->read(event); |
f344011c | 8337 | |
fd0d000b | 8338 | perf_sample_data_init(&data, 0, event->hw.last_period); |
b0a873eb PZ |
8339 | regs = get_irq_regs(); |
8340 | ||
8341 | if (regs && !perf_exclude_event(event, regs)) { | |
77aeeebd | 8342 | if (!(event->attr.exclude_idle && is_idle_task(current))) |
33b07b8b | 8343 | if (__perf_event_overflow(event, 1, &data, regs)) |
b0a873eb PZ |
8344 | ret = HRTIMER_NORESTART; |
8345 | } | |
24f1e32c | 8346 | |
b0a873eb PZ |
8347 | period = max_t(u64, 10000, event->hw.sample_period); |
8348 | hrtimer_forward_now(hrtimer, ns_to_ktime(period)); | |
24f1e32c | 8349 | |
b0a873eb | 8350 | return ret; |
f29ac756 PZ |
8351 | } |
8352 | ||
b0a873eb | 8353 | static void perf_swevent_start_hrtimer(struct perf_event *event) |
5c92d124 | 8354 | { |
b0a873eb | 8355 | struct hw_perf_event *hwc = &event->hw; |
5d508e82 FBH |
8356 | s64 period; |
8357 | ||
8358 | if (!is_sampling_event(event)) | |
8359 | return; | |
f5ffe02e | 8360 | |
5d508e82 FBH |
8361 | period = local64_read(&hwc->period_left); |
8362 | if (period) { | |
8363 | if (period < 0) | |
8364 | period = 10000; | |
fa407f35 | 8365 | |
5d508e82 FBH |
8366 | local64_set(&hwc->period_left, 0); |
8367 | } else { | |
8368 | period = max_t(u64, 10000, hwc->sample_period); | |
8369 | } | |
3497d206 TG |
8370 | hrtimer_start(&hwc->hrtimer, ns_to_ktime(period), |
8371 | HRTIMER_MODE_REL_PINNED); | |
24f1e32c | 8372 | } |
b0a873eb PZ |
8373 | |
8374 | static void perf_swevent_cancel_hrtimer(struct perf_event *event) | |
24f1e32c | 8375 | { |
b0a873eb PZ |
8376 | struct hw_perf_event *hwc = &event->hw; |
8377 | ||
6c7e550f | 8378 | if (is_sampling_event(event)) { |
b0a873eb | 8379 | ktime_t remaining = hrtimer_get_remaining(&hwc->hrtimer); |
fa407f35 | 8380 | local64_set(&hwc->period_left, ktime_to_ns(remaining)); |
b0a873eb PZ |
8381 | |
8382 | hrtimer_cancel(&hwc->hrtimer); | |
8383 | } | |
24f1e32c FW |
8384 | } |
8385 | ||
ba3dd36c PZ |
8386 | static void perf_swevent_init_hrtimer(struct perf_event *event) |
8387 | { | |
8388 | struct hw_perf_event *hwc = &event->hw; | |
8389 | ||
8390 | if (!is_sampling_event(event)) | |
8391 | return; | |
8392 | ||
8393 | hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); | |
8394 | hwc->hrtimer.function = perf_swevent_hrtimer; | |
8395 | ||
8396 | /* | |
8397 | * Since hrtimers have a fixed rate, we can do a static freq->period | |
8398 | * mapping and avoid the whole period adjust feedback stuff. | |
8399 | */ | |
8400 | if (event->attr.freq) { | |
8401 | long freq = event->attr.sample_freq; | |
8402 | ||
8403 | event->attr.sample_period = NSEC_PER_SEC / freq; | |
8404 | hwc->sample_period = event->attr.sample_period; | |
8405 | local64_set(&hwc->period_left, hwc->sample_period); | |
778141e3 | 8406 | hwc->last_period = hwc->sample_period; |
ba3dd36c PZ |
8407 | event->attr.freq = 0; |
8408 | } | |
8409 | } | |
8410 | ||
b0a873eb PZ |
8411 | /* |
8412 | * Software event: cpu wall time clock | |
8413 | */ | |
8414 | ||
8415 | static void cpu_clock_event_update(struct perf_event *event) | |
24f1e32c | 8416 | { |
b0a873eb PZ |
8417 | s64 prev; |
8418 | u64 now; | |
8419 | ||
a4eaf7f1 | 8420 | now = local_clock(); |
b0a873eb PZ |
8421 | prev = local64_xchg(&event->hw.prev_count, now); |
8422 | local64_add(now - prev, &event->count); | |
24f1e32c | 8423 | } |
24f1e32c | 8424 | |
a4eaf7f1 | 8425 | static void cpu_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 8426 | { |
a4eaf7f1 | 8427 | local64_set(&event->hw.prev_count, local_clock()); |
b0a873eb | 8428 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
8429 | } |
8430 | ||
a4eaf7f1 | 8431 | static void cpu_clock_event_stop(struct perf_event *event, int flags) |
f29ac756 | 8432 | { |
b0a873eb PZ |
8433 | perf_swevent_cancel_hrtimer(event); |
8434 | cpu_clock_event_update(event); | |
8435 | } | |
f29ac756 | 8436 | |
a4eaf7f1 PZ |
8437 | static int cpu_clock_event_add(struct perf_event *event, int flags) |
8438 | { | |
8439 | if (flags & PERF_EF_START) | |
8440 | cpu_clock_event_start(event, flags); | |
6a694a60 | 8441 | perf_event_update_userpage(event); |
a4eaf7f1 PZ |
8442 | |
8443 | return 0; | |
8444 | } | |
8445 | ||
8446 | static void cpu_clock_event_del(struct perf_event *event, int flags) | |
8447 | { | |
8448 | cpu_clock_event_stop(event, flags); | |
8449 | } | |
8450 | ||
b0a873eb PZ |
8451 | static void cpu_clock_event_read(struct perf_event *event) |
8452 | { | |
8453 | cpu_clock_event_update(event); | |
8454 | } | |
f344011c | 8455 | |
b0a873eb PZ |
8456 | static int cpu_clock_event_init(struct perf_event *event) |
8457 | { | |
8458 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
8459 | return -ENOENT; | |
8460 | ||
8461 | if (event->attr.config != PERF_COUNT_SW_CPU_CLOCK) | |
8462 | return -ENOENT; | |
8463 | ||
2481c5fa SE |
8464 | /* |
8465 | * no branch sampling for software events | |
8466 | */ | |
8467 | if (has_branch_stack(event)) | |
8468 | return -EOPNOTSUPP; | |
8469 | ||
ba3dd36c PZ |
8470 | perf_swevent_init_hrtimer(event); |
8471 | ||
b0a873eb | 8472 | return 0; |
f29ac756 PZ |
8473 | } |
8474 | ||
b0a873eb | 8475 | static struct pmu perf_cpu_clock = { |
89a1e187 PZ |
8476 | .task_ctx_nr = perf_sw_context, |
8477 | ||
34f43927 PZ |
8478 | .capabilities = PERF_PMU_CAP_NO_NMI, |
8479 | ||
b0a873eb | 8480 | .event_init = cpu_clock_event_init, |
a4eaf7f1 PZ |
8481 | .add = cpu_clock_event_add, |
8482 | .del = cpu_clock_event_del, | |
8483 | .start = cpu_clock_event_start, | |
8484 | .stop = cpu_clock_event_stop, | |
b0a873eb PZ |
8485 | .read = cpu_clock_event_read, |
8486 | }; | |
8487 | ||
8488 | /* | |
8489 | * Software event: task time clock | |
8490 | */ | |
8491 | ||
8492 | static void task_clock_event_update(struct perf_event *event, u64 now) | |
5c92d124 | 8493 | { |
b0a873eb PZ |
8494 | u64 prev; |
8495 | s64 delta; | |
5c92d124 | 8496 | |
b0a873eb PZ |
8497 | prev = local64_xchg(&event->hw.prev_count, now); |
8498 | delta = now - prev; | |
8499 | local64_add(delta, &event->count); | |
8500 | } | |
5c92d124 | 8501 | |
a4eaf7f1 | 8502 | static void task_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 8503 | { |
a4eaf7f1 | 8504 | local64_set(&event->hw.prev_count, event->ctx->time); |
b0a873eb | 8505 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
8506 | } |
8507 | ||
a4eaf7f1 | 8508 | static void task_clock_event_stop(struct perf_event *event, int flags) |
b0a873eb PZ |
8509 | { |
8510 | perf_swevent_cancel_hrtimer(event); | |
8511 | task_clock_event_update(event, event->ctx->time); | |
a4eaf7f1 PZ |
8512 | } |
8513 | ||
8514 | static int task_clock_event_add(struct perf_event *event, int flags) | |
8515 | { | |
8516 | if (flags & PERF_EF_START) | |
8517 | task_clock_event_start(event, flags); | |
6a694a60 | 8518 | perf_event_update_userpage(event); |
b0a873eb | 8519 | |
a4eaf7f1 PZ |
8520 | return 0; |
8521 | } | |
8522 | ||
8523 | static void task_clock_event_del(struct perf_event *event, int flags) | |
8524 | { | |
8525 | task_clock_event_stop(event, PERF_EF_UPDATE); | |
b0a873eb PZ |
8526 | } |
8527 | ||
8528 | static void task_clock_event_read(struct perf_event *event) | |
8529 | { | |
768a06e2 PZ |
8530 | u64 now = perf_clock(); |
8531 | u64 delta = now - event->ctx->timestamp; | |
8532 | u64 time = event->ctx->time + delta; | |
b0a873eb PZ |
8533 | |
8534 | task_clock_event_update(event, time); | |
8535 | } | |
8536 | ||
8537 | static int task_clock_event_init(struct perf_event *event) | |
6fb2915d | 8538 | { |
b0a873eb PZ |
8539 | if (event->attr.type != PERF_TYPE_SOFTWARE) |
8540 | return -ENOENT; | |
8541 | ||
8542 | if (event->attr.config != PERF_COUNT_SW_TASK_CLOCK) | |
8543 | return -ENOENT; | |
8544 | ||
2481c5fa SE |
8545 | /* |
8546 | * no branch sampling for software events | |
8547 | */ | |
8548 | if (has_branch_stack(event)) | |
8549 | return -EOPNOTSUPP; | |
8550 | ||
ba3dd36c PZ |
8551 | perf_swevent_init_hrtimer(event); |
8552 | ||
b0a873eb | 8553 | return 0; |
6fb2915d LZ |
8554 | } |
8555 | ||
b0a873eb | 8556 | static struct pmu perf_task_clock = { |
89a1e187 PZ |
8557 | .task_ctx_nr = perf_sw_context, |
8558 | ||
34f43927 PZ |
8559 | .capabilities = PERF_PMU_CAP_NO_NMI, |
8560 | ||
b0a873eb | 8561 | .event_init = task_clock_event_init, |
a4eaf7f1 PZ |
8562 | .add = task_clock_event_add, |
8563 | .del = task_clock_event_del, | |
8564 | .start = task_clock_event_start, | |
8565 | .stop = task_clock_event_stop, | |
b0a873eb PZ |
8566 | .read = task_clock_event_read, |
8567 | }; | |
6fb2915d | 8568 | |
ad5133b7 | 8569 | static void perf_pmu_nop_void(struct pmu *pmu) |
e077df4f | 8570 | { |
e077df4f | 8571 | } |
6fb2915d | 8572 | |
fbbe0701 SB |
8573 | static void perf_pmu_nop_txn(struct pmu *pmu, unsigned int flags) |
8574 | { | |
8575 | } | |
8576 | ||
ad5133b7 | 8577 | static int perf_pmu_nop_int(struct pmu *pmu) |
6fb2915d | 8578 | { |
ad5133b7 | 8579 | return 0; |
6fb2915d LZ |
8580 | } |
8581 | ||
18ab2cd3 | 8582 | static DEFINE_PER_CPU(unsigned int, nop_txn_flags); |
fbbe0701 SB |
8583 | |
8584 | static void perf_pmu_start_txn(struct pmu *pmu, unsigned int flags) | |
6fb2915d | 8585 | { |
fbbe0701 SB |
8586 | __this_cpu_write(nop_txn_flags, flags); |
8587 | ||
8588 | if (flags & ~PERF_PMU_TXN_ADD) | |
8589 | return; | |
8590 | ||
ad5133b7 | 8591 | perf_pmu_disable(pmu); |
6fb2915d LZ |
8592 | } |
8593 | ||
ad5133b7 PZ |
8594 | static int perf_pmu_commit_txn(struct pmu *pmu) |
8595 | { | |
fbbe0701 SB |
8596 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
8597 | ||
8598 | __this_cpu_write(nop_txn_flags, 0); | |
8599 | ||
8600 | if (flags & ~PERF_PMU_TXN_ADD) | |
8601 | return 0; | |
8602 | ||
ad5133b7 PZ |
8603 | perf_pmu_enable(pmu); |
8604 | return 0; | |
8605 | } | |
e077df4f | 8606 | |
ad5133b7 | 8607 | static void perf_pmu_cancel_txn(struct pmu *pmu) |
24f1e32c | 8608 | { |
fbbe0701 SB |
8609 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
8610 | ||
8611 | __this_cpu_write(nop_txn_flags, 0); | |
8612 | ||
8613 | if (flags & ~PERF_PMU_TXN_ADD) | |
8614 | return; | |
8615 | ||
ad5133b7 | 8616 | perf_pmu_enable(pmu); |
24f1e32c FW |
8617 | } |
8618 | ||
35edc2a5 PZ |
8619 | static int perf_event_idx_default(struct perf_event *event) |
8620 | { | |
c719f560 | 8621 | return 0; |
35edc2a5 PZ |
8622 | } |
8623 | ||
8dc85d54 PZ |
8624 | /* |
8625 | * Ensures all contexts with the same task_ctx_nr have the same | |
8626 | * pmu_cpu_context too. | |
8627 | */ | |
9e317041 | 8628 | static struct perf_cpu_context __percpu *find_pmu_context(int ctxn) |
24f1e32c | 8629 | { |
8dc85d54 | 8630 | struct pmu *pmu; |
b326e956 | 8631 | |
8dc85d54 PZ |
8632 | if (ctxn < 0) |
8633 | return NULL; | |
24f1e32c | 8634 | |
8dc85d54 PZ |
8635 | list_for_each_entry(pmu, &pmus, entry) { |
8636 | if (pmu->task_ctx_nr == ctxn) | |
8637 | return pmu->pmu_cpu_context; | |
8638 | } | |
24f1e32c | 8639 | |
8dc85d54 | 8640 | return NULL; |
24f1e32c FW |
8641 | } |
8642 | ||
51676957 PZ |
8643 | static void free_pmu_context(struct pmu *pmu) |
8644 | { | |
8dc85d54 | 8645 | mutex_lock(&pmus_lock); |
51676957 | 8646 | free_percpu(pmu->pmu_cpu_context); |
8dc85d54 | 8647 | mutex_unlock(&pmus_lock); |
24f1e32c | 8648 | } |
6e855cd4 AS |
8649 | |
8650 | /* | |
8651 | * Let userspace know that this PMU supports address range filtering: | |
8652 | */ | |
8653 | static ssize_t nr_addr_filters_show(struct device *dev, | |
8654 | struct device_attribute *attr, | |
8655 | char *page) | |
8656 | { | |
8657 | struct pmu *pmu = dev_get_drvdata(dev); | |
8658 | ||
8659 | return snprintf(page, PAGE_SIZE - 1, "%d\n", pmu->nr_addr_filters); | |
8660 | } | |
8661 | DEVICE_ATTR_RO(nr_addr_filters); | |
8662 | ||
2e80a82a | 8663 | static struct idr pmu_idr; |
d6d020e9 | 8664 | |
abe43400 PZ |
8665 | static ssize_t |
8666 | type_show(struct device *dev, struct device_attribute *attr, char *page) | |
8667 | { | |
8668 | struct pmu *pmu = dev_get_drvdata(dev); | |
8669 | ||
8670 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->type); | |
8671 | } | |
90826ca7 | 8672 | static DEVICE_ATTR_RO(type); |
abe43400 | 8673 | |
62b85639 SE |
8674 | static ssize_t |
8675 | perf_event_mux_interval_ms_show(struct device *dev, | |
8676 | struct device_attribute *attr, | |
8677 | char *page) | |
8678 | { | |
8679 | struct pmu *pmu = dev_get_drvdata(dev); | |
8680 | ||
8681 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->hrtimer_interval_ms); | |
8682 | } | |
8683 | ||
272325c4 PZ |
8684 | static DEFINE_MUTEX(mux_interval_mutex); |
8685 | ||
62b85639 SE |
8686 | static ssize_t |
8687 | perf_event_mux_interval_ms_store(struct device *dev, | |
8688 | struct device_attribute *attr, | |
8689 | const char *buf, size_t count) | |
8690 | { | |
8691 | struct pmu *pmu = dev_get_drvdata(dev); | |
8692 | int timer, cpu, ret; | |
8693 | ||
8694 | ret = kstrtoint(buf, 0, &timer); | |
8695 | if (ret) | |
8696 | return ret; | |
8697 | ||
8698 | if (timer < 1) | |
8699 | return -EINVAL; | |
8700 | ||
8701 | /* same value, noting to do */ | |
8702 | if (timer == pmu->hrtimer_interval_ms) | |
8703 | return count; | |
8704 | ||
272325c4 | 8705 | mutex_lock(&mux_interval_mutex); |
62b85639 SE |
8706 | pmu->hrtimer_interval_ms = timer; |
8707 | ||
8708 | /* update all cpuctx for this PMU */ | |
272325c4 PZ |
8709 | get_online_cpus(); |
8710 | for_each_online_cpu(cpu) { | |
62b85639 SE |
8711 | struct perf_cpu_context *cpuctx; |
8712 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
8713 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * timer); | |
8714 | ||
272325c4 PZ |
8715 | cpu_function_call(cpu, |
8716 | (remote_function_f)perf_mux_hrtimer_restart, cpuctx); | |
62b85639 | 8717 | } |
272325c4 PZ |
8718 | put_online_cpus(); |
8719 | mutex_unlock(&mux_interval_mutex); | |
62b85639 SE |
8720 | |
8721 | return count; | |
8722 | } | |
90826ca7 | 8723 | static DEVICE_ATTR_RW(perf_event_mux_interval_ms); |
62b85639 | 8724 | |
90826ca7 GKH |
8725 | static struct attribute *pmu_dev_attrs[] = { |
8726 | &dev_attr_type.attr, | |
8727 | &dev_attr_perf_event_mux_interval_ms.attr, | |
8728 | NULL, | |
abe43400 | 8729 | }; |
90826ca7 | 8730 | ATTRIBUTE_GROUPS(pmu_dev); |
abe43400 PZ |
8731 | |
8732 | static int pmu_bus_running; | |
8733 | static struct bus_type pmu_bus = { | |
8734 | .name = "event_source", | |
90826ca7 | 8735 | .dev_groups = pmu_dev_groups, |
abe43400 PZ |
8736 | }; |
8737 | ||
8738 | static void pmu_dev_release(struct device *dev) | |
8739 | { | |
8740 | kfree(dev); | |
8741 | } | |
8742 | ||
8743 | static int pmu_dev_alloc(struct pmu *pmu) | |
8744 | { | |
8745 | int ret = -ENOMEM; | |
8746 | ||
8747 | pmu->dev = kzalloc(sizeof(struct device), GFP_KERNEL); | |
8748 | if (!pmu->dev) | |
8749 | goto out; | |
8750 | ||
0c9d42ed | 8751 | pmu->dev->groups = pmu->attr_groups; |
abe43400 PZ |
8752 | device_initialize(pmu->dev); |
8753 | ret = dev_set_name(pmu->dev, "%s", pmu->name); | |
8754 | if (ret) | |
8755 | goto free_dev; | |
8756 | ||
8757 | dev_set_drvdata(pmu->dev, pmu); | |
8758 | pmu->dev->bus = &pmu_bus; | |
8759 | pmu->dev->release = pmu_dev_release; | |
8760 | ret = device_add(pmu->dev); | |
8761 | if (ret) | |
8762 | goto free_dev; | |
8763 | ||
6e855cd4 AS |
8764 | /* For PMUs with address filters, throw in an extra attribute: */ |
8765 | if (pmu->nr_addr_filters) | |
8766 | ret = device_create_file(pmu->dev, &dev_attr_nr_addr_filters); | |
8767 | ||
8768 | if (ret) | |
8769 | goto del_dev; | |
8770 | ||
abe43400 PZ |
8771 | out: |
8772 | return ret; | |
8773 | ||
6e855cd4 AS |
8774 | del_dev: |
8775 | device_del(pmu->dev); | |
8776 | ||
abe43400 PZ |
8777 | free_dev: |
8778 | put_device(pmu->dev); | |
8779 | goto out; | |
8780 | } | |
8781 | ||
547e9fd7 | 8782 | static struct lock_class_key cpuctx_mutex; |
facc4307 | 8783 | static struct lock_class_key cpuctx_lock; |
547e9fd7 | 8784 | |
03d8e80b | 8785 | int perf_pmu_register(struct pmu *pmu, const char *name, int type) |
24f1e32c | 8786 | { |
108b02cf | 8787 | int cpu, ret; |
24f1e32c | 8788 | |
b0a873eb | 8789 | mutex_lock(&pmus_lock); |
33696fc0 PZ |
8790 | ret = -ENOMEM; |
8791 | pmu->pmu_disable_count = alloc_percpu(int); | |
8792 | if (!pmu->pmu_disable_count) | |
8793 | goto unlock; | |
f29ac756 | 8794 | |
2e80a82a PZ |
8795 | pmu->type = -1; |
8796 | if (!name) | |
8797 | goto skip_type; | |
8798 | pmu->name = name; | |
8799 | ||
8800 | if (type < 0) { | |
0e9c3be2 TH |
8801 | type = idr_alloc(&pmu_idr, pmu, PERF_TYPE_MAX, 0, GFP_KERNEL); |
8802 | if (type < 0) { | |
8803 | ret = type; | |
2e80a82a PZ |
8804 | goto free_pdc; |
8805 | } | |
8806 | } | |
8807 | pmu->type = type; | |
8808 | ||
abe43400 PZ |
8809 | if (pmu_bus_running) { |
8810 | ret = pmu_dev_alloc(pmu); | |
8811 | if (ret) | |
8812 | goto free_idr; | |
8813 | } | |
8814 | ||
2e80a82a | 8815 | skip_type: |
26657848 PZ |
8816 | if (pmu->task_ctx_nr == perf_hw_context) { |
8817 | static int hw_context_taken = 0; | |
8818 | ||
5101ef20 MR |
8819 | /* |
8820 | * Other than systems with heterogeneous CPUs, it never makes | |
8821 | * sense for two PMUs to share perf_hw_context. PMUs which are | |
8822 | * uncore must use perf_invalid_context. | |
8823 | */ | |
8824 | if (WARN_ON_ONCE(hw_context_taken && | |
8825 | !(pmu->capabilities & PERF_PMU_CAP_HETEROGENEOUS_CPUS))) | |
26657848 PZ |
8826 | pmu->task_ctx_nr = perf_invalid_context; |
8827 | ||
8828 | hw_context_taken = 1; | |
8829 | } | |
8830 | ||
8dc85d54 PZ |
8831 | pmu->pmu_cpu_context = find_pmu_context(pmu->task_ctx_nr); |
8832 | if (pmu->pmu_cpu_context) | |
8833 | goto got_cpu_context; | |
f29ac756 | 8834 | |
c4814202 | 8835 | ret = -ENOMEM; |
108b02cf PZ |
8836 | pmu->pmu_cpu_context = alloc_percpu(struct perf_cpu_context); |
8837 | if (!pmu->pmu_cpu_context) | |
abe43400 | 8838 | goto free_dev; |
f344011c | 8839 | |
108b02cf PZ |
8840 | for_each_possible_cpu(cpu) { |
8841 | struct perf_cpu_context *cpuctx; | |
8842 | ||
8843 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
eb184479 | 8844 | __perf_event_init_context(&cpuctx->ctx); |
547e9fd7 | 8845 | lockdep_set_class(&cpuctx->ctx.mutex, &cpuctx_mutex); |
facc4307 | 8846 | lockdep_set_class(&cpuctx->ctx.lock, &cpuctx_lock); |
108b02cf | 8847 | cpuctx->ctx.pmu = pmu; |
9e630205 | 8848 | |
272325c4 | 8849 | __perf_mux_hrtimer_init(cpuctx, cpu); |
108b02cf | 8850 | } |
76e1d904 | 8851 | |
8dc85d54 | 8852 | got_cpu_context: |
ad5133b7 PZ |
8853 | if (!pmu->start_txn) { |
8854 | if (pmu->pmu_enable) { | |
8855 | /* | |
8856 | * If we have pmu_enable/pmu_disable calls, install | |
8857 | * transaction stubs that use that to try and batch | |
8858 | * hardware accesses. | |
8859 | */ | |
8860 | pmu->start_txn = perf_pmu_start_txn; | |
8861 | pmu->commit_txn = perf_pmu_commit_txn; | |
8862 | pmu->cancel_txn = perf_pmu_cancel_txn; | |
8863 | } else { | |
fbbe0701 | 8864 | pmu->start_txn = perf_pmu_nop_txn; |
ad5133b7 PZ |
8865 | pmu->commit_txn = perf_pmu_nop_int; |
8866 | pmu->cancel_txn = perf_pmu_nop_void; | |
f344011c | 8867 | } |
5c92d124 | 8868 | } |
15dbf27c | 8869 | |
ad5133b7 PZ |
8870 | if (!pmu->pmu_enable) { |
8871 | pmu->pmu_enable = perf_pmu_nop_void; | |
8872 | pmu->pmu_disable = perf_pmu_nop_void; | |
8873 | } | |
8874 | ||
35edc2a5 PZ |
8875 | if (!pmu->event_idx) |
8876 | pmu->event_idx = perf_event_idx_default; | |
8877 | ||
b0a873eb | 8878 | list_add_rcu(&pmu->entry, &pmus); |
bed5b25a | 8879 | atomic_set(&pmu->exclusive_cnt, 0); |
33696fc0 PZ |
8880 | ret = 0; |
8881 | unlock: | |
b0a873eb PZ |
8882 | mutex_unlock(&pmus_lock); |
8883 | ||
33696fc0 | 8884 | return ret; |
108b02cf | 8885 | |
abe43400 PZ |
8886 | free_dev: |
8887 | device_del(pmu->dev); | |
8888 | put_device(pmu->dev); | |
8889 | ||
2e80a82a PZ |
8890 | free_idr: |
8891 | if (pmu->type >= PERF_TYPE_MAX) | |
8892 | idr_remove(&pmu_idr, pmu->type); | |
8893 | ||
108b02cf PZ |
8894 | free_pdc: |
8895 | free_percpu(pmu->pmu_disable_count); | |
8896 | goto unlock; | |
f29ac756 | 8897 | } |
c464c76e | 8898 | EXPORT_SYMBOL_GPL(perf_pmu_register); |
f29ac756 | 8899 | |
b0a873eb | 8900 | void perf_pmu_unregister(struct pmu *pmu) |
5c92d124 | 8901 | { |
0933840a JO |
8902 | int remove_device; |
8903 | ||
b0a873eb | 8904 | mutex_lock(&pmus_lock); |
0933840a | 8905 | remove_device = pmu_bus_running; |
b0a873eb PZ |
8906 | list_del_rcu(&pmu->entry); |
8907 | mutex_unlock(&pmus_lock); | |
5c92d124 | 8908 | |
0475f9ea | 8909 | /* |
cde8e884 PZ |
8910 | * We dereference the pmu list under both SRCU and regular RCU, so |
8911 | * synchronize against both of those. | |
0475f9ea | 8912 | */ |
b0a873eb | 8913 | synchronize_srcu(&pmus_srcu); |
cde8e884 | 8914 | synchronize_rcu(); |
d6d020e9 | 8915 | |
33696fc0 | 8916 | free_percpu(pmu->pmu_disable_count); |
2e80a82a PZ |
8917 | if (pmu->type >= PERF_TYPE_MAX) |
8918 | idr_remove(&pmu_idr, pmu->type); | |
0933840a JO |
8919 | if (remove_device) { |
8920 | if (pmu->nr_addr_filters) | |
8921 | device_remove_file(pmu->dev, &dev_attr_nr_addr_filters); | |
8922 | device_del(pmu->dev); | |
8923 | put_device(pmu->dev); | |
8924 | } | |
51676957 | 8925 | free_pmu_context(pmu); |
b0a873eb | 8926 | } |
c464c76e | 8927 | EXPORT_SYMBOL_GPL(perf_pmu_unregister); |
d6d020e9 | 8928 | |
cc34b98b MR |
8929 | static int perf_try_init_event(struct pmu *pmu, struct perf_event *event) |
8930 | { | |
ccd41c86 | 8931 | struct perf_event_context *ctx = NULL; |
cc34b98b MR |
8932 | int ret; |
8933 | ||
8934 | if (!try_module_get(pmu->module)) | |
8935 | return -ENODEV; | |
ccd41c86 PZ |
8936 | |
8937 | if (event->group_leader != event) { | |
8b10c5e2 PZ |
8938 | /* |
8939 | * This ctx->mutex can nest when we're called through | |
8940 | * inheritance. See the perf_event_ctx_lock_nested() comment. | |
8941 | */ | |
8942 | ctx = perf_event_ctx_lock_nested(event->group_leader, | |
8943 | SINGLE_DEPTH_NESTING); | |
ccd41c86 PZ |
8944 | BUG_ON(!ctx); |
8945 | } | |
8946 | ||
cc34b98b MR |
8947 | event->pmu = pmu; |
8948 | ret = pmu->event_init(event); | |
ccd41c86 PZ |
8949 | |
8950 | if (ctx) | |
8951 | perf_event_ctx_unlock(event->group_leader, ctx); | |
8952 | ||
cc34b98b MR |
8953 | if (ret) |
8954 | module_put(pmu->module); | |
8955 | ||
8956 | return ret; | |
8957 | } | |
8958 | ||
18ab2cd3 | 8959 | static struct pmu *perf_init_event(struct perf_event *event) |
b0a873eb PZ |
8960 | { |
8961 | struct pmu *pmu = NULL; | |
8962 | int idx; | |
940c5b29 | 8963 | int ret; |
b0a873eb PZ |
8964 | |
8965 | idx = srcu_read_lock(&pmus_srcu); | |
2e80a82a PZ |
8966 | |
8967 | rcu_read_lock(); | |
8968 | pmu = idr_find(&pmu_idr, event->attr.type); | |
8969 | rcu_read_unlock(); | |
940c5b29 | 8970 | if (pmu) { |
cc34b98b | 8971 | ret = perf_try_init_event(pmu, event); |
940c5b29 LM |
8972 | if (ret) |
8973 | pmu = ERR_PTR(ret); | |
2e80a82a | 8974 | goto unlock; |
940c5b29 | 8975 | } |
2e80a82a | 8976 | |
b0a873eb | 8977 | list_for_each_entry_rcu(pmu, &pmus, entry) { |
cc34b98b | 8978 | ret = perf_try_init_event(pmu, event); |
b0a873eb | 8979 | if (!ret) |
e5f4d339 | 8980 | goto unlock; |
76e1d904 | 8981 | |
b0a873eb PZ |
8982 | if (ret != -ENOENT) { |
8983 | pmu = ERR_PTR(ret); | |
e5f4d339 | 8984 | goto unlock; |
f344011c | 8985 | } |
5c92d124 | 8986 | } |
e5f4d339 PZ |
8987 | pmu = ERR_PTR(-ENOENT); |
8988 | unlock: | |
b0a873eb | 8989 | srcu_read_unlock(&pmus_srcu, idx); |
15dbf27c | 8990 | |
4aeb0b42 | 8991 | return pmu; |
5c92d124 IM |
8992 | } |
8993 | ||
f2fb6bef KL |
8994 | static void attach_sb_event(struct perf_event *event) |
8995 | { | |
8996 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
8997 | ||
8998 | raw_spin_lock(&pel->lock); | |
8999 | list_add_rcu(&event->sb_list, &pel->list); | |
9000 | raw_spin_unlock(&pel->lock); | |
9001 | } | |
9002 | ||
aab5b71e PZ |
9003 | /* |
9004 | * We keep a list of all !task (and therefore per-cpu) events | |
9005 | * that need to receive side-band records. | |
9006 | * | |
9007 | * This avoids having to scan all the various PMU per-cpu contexts | |
9008 | * looking for them. | |
9009 | */ | |
f2fb6bef KL |
9010 | static void account_pmu_sb_event(struct perf_event *event) |
9011 | { | |
a4f144eb | 9012 | if (is_sb_event(event)) |
f2fb6bef KL |
9013 | attach_sb_event(event); |
9014 | } | |
9015 | ||
4beb31f3 FW |
9016 | static void account_event_cpu(struct perf_event *event, int cpu) |
9017 | { | |
9018 | if (event->parent) | |
9019 | return; | |
9020 | ||
4beb31f3 FW |
9021 | if (is_cgroup_event(event)) |
9022 | atomic_inc(&per_cpu(perf_cgroup_events, cpu)); | |
9023 | } | |
9024 | ||
555e0c1e FW |
9025 | /* Freq events need the tick to stay alive (see perf_event_task_tick). */ |
9026 | static void account_freq_event_nohz(void) | |
9027 | { | |
9028 | #ifdef CONFIG_NO_HZ_FULL | |
9029 | /* Lock so we don't race with concurrent unaccount */ | |
9030 | spin_lock(&nr_freq_lock); | |
9031 | if (atomic_inc_return(&nr_freq_events) == 1) | |
9032 | tick_nohz_dep_set(TICK_DEP_BIT_PERF_EVENTS); | |
9033 | spin_unlock(&nr_freq_lock); | |
9034 | #endif | |
9035 | } | |
9036 | ||
9037 | static void account_freq_event(void) | |
9038 | { | |
9039 | if (tick_nohz_full_enabled()) | |
9040 | account_freq_event_nohz(); | |
9041 | else | |
9042 | atomic_inc(&nr_freq_events); | |
9043 | } | |
9044 | ||
9045 | ||
766d6c07 FW |
9046 | static void account_event(struct perf_event *event) |
9047 | { | |
25432ae9 PZ |
9048 | bool inc = false; |
9049 | ||
4beb31f3 FW |
9050 | if (event->parent) |
9051 | return; | |
9052 | ||
766d6c07 | 9053 | if (event->attach_state & PERF_ATTACH_TASK) |
25432ae9 | 9054 | inc = true; |
766d6c07 FW |
9055 | if (event->attr.mmap || event->attr.mmap_data) |
9056 | atomic_inc(&nr_mmap_events); | |
9057 | if (event->attr.comm) | |
9058 | atomic_inc(&nr_comm_events); | |
9059 | if (event->attr.task) | |
9060 | atomic_inc(&nr_task_events); | |
555e0c1e FW |
9061 | if (event->attr.freq) |
9062 | account_freq_event(); | |
45ac1403 AH |
9063 | if (event->attr.context_switch) { |
9064 | atomic_inc(&nr_switch_events); | |
25432ae9 | 9065 | inc = true; |
45ac1403 | 9066 | } |
4beb31f3 | 9067 | if (has_branch_stack(event)) |
25432ae9 | 9068 | inc = true; |
4beb31f3 | 9069 | if (is_cgroup_event(event)) |
25432ae9 PZ |
9070 | inc = true; |
9071 | ||
9107c89e PZ |
9072 | if (inc) { |
9073 | if (atomic_inc_not_zero(&perf_sched_count)) | |
9074 | goto enabled; | |
9075 | ||
9076 | mutex_lock(&perf_sched_mutex); | |
9077 | if (!atomic_read(&perf_sched_count)) { | |
9078 | static_branch_enable(&perf_sched_events); | |
9079 | /* | |
9080 | * Guarantee that all CPUs observe they key change and | |
9081 | * call the perf scheduling hooks before proceeding to | |
9082 | * install events that need them. | |
9083 | */ | |
9084 | synchronize_sched(); | |
9085 | } | |
9086 | /* | |
9087 | * Now that we have waited for the sync_sched(), allow further | |
9088 | * increments to by-pass the mutex. | |
9089 | */ | |
9090 | atomic_inc(&perf_sched_count); | |
9091 | mutex_unlock(&perf_sched_mutex); | |
9092 | } | |
9093 | enabled: | |
4beb31f3 FW |
9094 | |
9095 | account_event_cpu(event, event->cpu); | |
f2fb6bef KL |
9096 | |
9097 | account_pmu_sb_event(event); | |
766d6c07 FW |
9098 | } |
9099 | ||
0793a61d | 9100 | /* |
cdd6c482 | 9101 | * Allocate and initialize a event structure |
0793a61d | 9102 | */ |
cdd6c482 | 9103 | static struct perf_event * |
c3f00c70 | 9104 | perf_event_alloc(struct perf_event_attr *attr, int cpu, |
d580ff86 PZ |
9105 | struct task_struct *task, |
9106 | struct perf_event *group_leader, | |
9107 | struct perf_event *parent_event, | |
4dc0da86 | 9108 | perf_overflow_handler_t overflow_handler, |
79dff51e | 9109 | void *context, int cgroup_fd) |
0793a61d | 9110 | { |
51b0fe39 | 9111 | struct pmu *pmu; |
cdd6c482 IM |
9112 | struct perf_event *event; |
9113 | struct hw_perf_event *hwc; | |
90983b16 | 9114 | long err = -EINVAL; |
0793a61d | 9115 | |
66832eb4 ON |
9116 | if ((unsigned)cpu >= nr_cpu_ids) { |
9117 | if (!task || cpu != -1) | |
9118 | return ERR_PTR(-EINVAL); | |
9119 | } | |
9120 | ||
c3f00c70 | 9121 | event = kzalloc(sizeof(*event), GFP_KERNEL); |
cdd6c482 | 9122 | if (!event) |
d5d2bc0d | 9123 | return ERR_PTR(-ENOMEM); |
0793a61d | 9124 | |
04289bb9 | 9125 | /* |
cdd6c482 | 9126 | * Single events are their own group leaders, with an |
04289bb9 IM |
9127 | * empty sibling list: |
9128 | */ | |
9129 | if (!group_leader) | |
cdd6c482 | 9130 | group_leader = event; |
04289bb9 | 9131 | |
cdd6c482 IM |
9132 | mutex_init(&event->child_mutex); |
9133 | INIT_LIST_HEAD(&event->child_list); | |
fccc714b | 9134 | |
cdd6c482 IM |
9135 | INIT_LIST_HEAD(&event->group_entry); |
9136 | INIT_LIST_HEAD(&event->event_entry); | |
9137 | INIT_LIST_HEAD(&event->sibling_list); | |
10c6db11 | 9138 | INIT_LIST_HEAD(&event->rb_entry); |
71ad88ef | 9139 | INIT_LIST_HEAD(&event->active_entry); |
375637bc | 9140 | INIT_LIST_HEAD(&event->addr_filters.list); |
f3ae75de SE |
9141 | INIT_HLIST_NODE(&event->hlist_entry); |
9142 | ||
10c6db11 | 9143 | |
cdd6c482 | 9144 | init_waitqueue_head(&event->waitq); |
e360adbe | 9145 | init_irq_work(&event->pending, perf_pending_event); |
0793a61d | 9146 | |
cdd6c482 | 9147 | mutex_init(&event->mmap_mutex); |
375637bc | 9148 | raw_spin_lock_init(&event->addr_filters.lock); |
7b732a75 | 9149 | |
a6fa941d | 9150 | atomic_long_set(&event->refcount, 1); |
cdd6c482 IM |
9151 | event->cpu = cpu; |
9152 | event->attr = *attr; | |
9153 | event->group_leader = group_leader; | |
9154 | event->pmu = NULL; | |
cdd6c482 | 9155 | event->oncpu = -1; |
a96bbc16 | 9156 | |
cdd6c482 | 9157 | event->parent = parent_event; |
b84fbc9f | 9158 | |
17cf22c3 | 9159 | event->ns = get_pid_ns(task_active_pid_ns(current)); |
cdd6c482 | 9160 | event->id = atomic64_inc_return(&perf_event_id); |
a96bbc16 | 9161 | |
cdd6c482 | 9162 | event->state = PERF_EVENT_STATE_INACTIVE; |
329d876d | 9163 | |
d580ff86 PZ |
9164 | if (task) { |
9165 | event->attach_state = PERF_ATTACH_TASK; | |
d580ff86 | 9166 | /* |
50f16a8b PZ |
9167 | * XXX pmu::event_init needs to know what task to account to |
9168 | * and we cannot use the ctx information because we need the | |
9169 | * pmu before we get a ctx. | |
d580ff86 | 9170 | */ |
50f16a8b | 9171 | event->hw.target = task; |
d580ff86 PZ |
9172 | } |
9173 | ||
34f43927 PZ |
9174 | event->clock = &local_clock; |
9175 | if (parent_event) | |
9176 | event->clock = parent_event->clock; | |
9177 | ||
4dc0da86 | 9178 | if (!overflow_handler && parent_event) { |
b326e956 | 9179 | overflow_handler = parent_event->overflow_handler; |
4dc0da86 | 9180 | context = parent_event->overflow_handler_context; |
f1e4ba5b | 9181 | #if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_EVENT_TRACING) |
aa6a5f3c AS |
9182 | if (overflow_handler == bpf_overflow_handler) { |
9183 | struct bpf_prog *prog = bpf_prog_inc(parent_event->prog); | |
9184 | ||
9185 | if (IS_ERR(prog)) { | |
9186 | err = PTR_ERR(prog); | |
9187 | goto err_ns; | |
9188 | } | |
9189 | event->prog = prog; | |
9190 | event->orig_overflow_handler = | |
9191 | parent_event->orig_overflow_handler; | |
9192 | } | |
9193 | #endif | |
4dc0da86 | 9194 | } |
66832eb4 | 9195 | |
1879445d WN |
9196 | if (overflow_handler) { |
9197 | event->overflow_handler = overflow_handler; | |
9198 | event->overflow_handler_context = context; | |
9ecda41a WN |
9199 | } else if (is_write_backward(event)){ |
9200 | event->overflow_handler = perf_event_output_backward; | |
9201 | event->overflow_handler_context = NULL; | |
1879445d | 9202 | } else { |
9ecda41a | 9203 | event->overflow_handler = perf_event_output_forward; |
1879445d WN |
9204 | event->overflow_handler_context = NULL; |
9205 | } | |
97eaf530 | 9206 | |
0231bb53 | 9207 | perf_event__state_init(event); |
a86ed508 | 9208 | |
4aeb0b42 | 9209 | pmu = NULL; |
b8e83514 | 9210 | |
cdd6c482 | 9211 | hwc = &event->hw; |
bd2b5b12 | 9212 | hwc->sample_period = attr->sample_period; |
0d48696f | 9213 | if (attr->freq && attr->sample_freq) |
bd2b5b12 | 9214 | hwc->sample_period = 1; |
eced1dfc | 9215 | hwc->last_period = hwc->sample_period; |
bd2b5b12 | 9216 | |
e7850595 | 9217 | local64_set(&hwc->period_left, hwc->sample_period); |
60db5e09 | 9218 | |
2023b359 | 9219 | /* |
cdd6c482 | 9220 | * we currently do not support PERF_FORMAT_GROUP on inherited events |
2023b359 | 9221 | */ |
3dab77fb | 9222 | if (attr->inherit && (attr->read_format & PERF_FORMAT_GROUP)) |
90983b16 | 9223 | goto err_ns; |
a46a2300 YZ |
9224 | |
9225 | if (!has_branch_stack(event)) | |
9226 | event->attr.branch_sample_type = 0; | |
2023b359 | 9227 | |
79dff51e MF |
9228 | if (cgroup_fd != -1) { |
9229 | err = perf_cgroup_connect(cgroup_fd, event, attr, group_leader); | |
9230 | if (err) | |
9231 | goto err_ns; | |
9232 | } | |
9233 | ||
b0a873eb | 9234 | pmu = perf_init_event(event); |
4aeb0b42 | 9235 | if (!pmu) |
90983b16 FW |
9236 | goto err_ns; |
9237 | else if (IS_ERR(pmu)) { | |
4aeb0b42 | 9238 | err = PTR_ERR(pmu); |
90983b16 | 9239 | goto err_ns; |
621a01ea | 9240 | } |
d5d2bc0d | 9241 | |
bed5b25a AS |
9242 | err = exclusive_event_init(event); |
9243 | if (err) | |
9244 | goto err_pmu; | |
9245 | ||
375637bc AS |
9246 | if (has_addr_filter(event)) { |
9247 | event->addr_filters_offs = kcalloc(pmu->nr_addr_filters, | |
9248 | sizeof(unsigned long), | |
9249 | GFP_KERNEL); | |
9250 | if (!event->addr_filters_offs) | |
9251 | goto err_per_task; | |
9252 | ||
9253 | /* force hw sync on the address filters */ | |
9254 | event->addr_filters_gen = 1; | |
9255 | } | |
9256 | ||
cdd6c482 | 9257 | if (!event->parent) { |
927c7a9e | 9258 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) { |
97c79a38 | 9259 | err = get_callchain_buffers(attr->sample_max_stack); |
90983b16 | 9260 | if (err) |
375637bc | 9261 | goto err_addr_filters; |
d010b332 | 9262 | } |
f344011c | 9263 | } |
9ee318a7 | 9264 | |
927a5570 AS |
9265 | /* symmetric to unaccount_event() in _free_event() */ |
9266 | account_event(event); | |
9267 | ||
cdd6c482 | 9268 | return event; |
90983b16 | 9269 | |
375637bc AS |
9270 | err_addr_filters: |
9271 | kfree(event->addr_filters_offs); | |
9272 | ||
bed5b25a AS |
9273 | err_per_task: |
9274 | exclusive_event_destroy(event); | |
9275 | ||
90983b16 FW |
9276 | err_pmu: |
9277 | if (event->destroy) | |
9278 | event->destroy(event); | |
c464c76e | 9279 | module_put(pmu->module); |
90983b16 | 9280 | err_ns: |
79dff51e MF |
9281 | if (is_cgroup_event(event)) |
9282 | perf_detach_cgroup(event); | |
90983b16 FW |
9283 | if (event->ns) |
9284 | put_pid_ns(event->ns); | |
9285 | kfree(event); | |
9286 | ||
9287 | return ERR_PTR(err); | |
0793a61d TG |
9288 | } |
9289 | ||
cdd6c482 IM |
9290 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
9291 | struct perf_event_attr *attr) | |
974802ea | 9292 | { |
974802ea | 9293 | u32 size; |
cdf8073d | 9294 | int ret; |
974802ea PZ |
9295 | |
9296 | if (!access_ok(VERIFY_WRITE, uattr, PERF_ATTR_SIZE_VER0)) | |
9297 | return -EFAULT; | |
9298 | ||
9299 | /* | |
9300 | * zero the full structure, so that a short copy will be nice. | |
9301 | */ | |
9302 | memset(attr, 0, sizeof(*attr)); | |
9303 | ||
9304 | ret = get_user(size, &uattr->size); | |
9305 | if (ret) | |
9306 | return ret; | |
9307 | ||
9308 | if (size > PAGE_SIZE) /* silly large */ | |
9309 | goto err_size; | |
9310 | ||
9311 | if (!size) /* abi compat */ | |
9312 | size = PERF_ATTR_SIZE_VER0; | |
9313 | ||
9314 | if (size < PERF_ATTR_SIZE_VER0) | |
9315 | goto err_size; | |
9316 | ||
9317 | /* | |
9318 | * If we're handed a bigger struct than we know of, | |
cdf8073d IS |
9319 | * ensure all the unknown bits are 0 - i.e. new |
9320 | * user-space does not rely on any kernel feature | |
9321 | * extensions we dont know about yet. | |
974802ea PZ |
9322 | */ |
9323 | if (size > sizeof(*attr)) { | |
cdf8073d IS |
9324 | unsigned char __user *addr; |
9325 | unsigned char __user *end; | |
9326 | unsigned char val; | |
974802ea | 9327 | |
cdf8073d IS |
9328 | addr = (void __user *)uattr + sizeof(*attr); |
9329 | end = (void __user *)uattr + size; | |
974802ea | 9330 | |
cdf8073d | 9331 | for (; addr < end; addr++) { |
974802ea PZ |
9332 | ret = get_user(val, addr); |
9333 | if (ret) | |
9334 | return ret; | |
9335 | if (val) | |
9336 | goto err_size; | |
9337 | } | |
b3e62e35 | 9338 | size = sizeof(*attr); |
974802ea PZ |
9339 | } |
9340 | ||
9341 | ret = copy_from_user(attr, uattr, size); | |
9342 | if (ret) | |
9343 | return -EFAULT; | |
9344 | ||
cd757645 | 9345 | if (attr->__reserved_1) |
974802ea PZ |
9346 | return -EINVAL; |
9347 | ||
9348 | if (attr->sample_type & ~(PERF_SAMPLE_MAX-1)) | |
9349 | return -EINVAL; | |
9350 | ||
9351 | if (attr->read_format & ~(PERF_FORMAT_MAX-1)) | |
9352 | return -EINVAL; | |
9353 | ||
bce38cd5 SE |
9354 | if (attr->sample_type & PERF_SAMPLE_BRANCH_STACK) { |
9355 | u64 mask = attr->branch_sample_type; | |
9356 | ||
9357 | /* only using defined bits */ | |
9358 | if (mask & ~(PERF_SAMPLE_BRANCH_MAX-1)) | |
9359 | return -EINVAL; | |
9360 | ||
9361 | /* at least one branch bit must be set */ | |
9362 | if (!(mask & ~PERF_SAMPLE_BRANCH_PLM_ALL)) | |
9363 | return -EINVAL; | |
9364 | ||
bce38cd5 SE |
9365 | /* propagate priv level, when not set for branch */ |
9366 | if (!(mask & PERF_SAMPLE_BRANCH_PLM_ALL)) { | |
9367 | ||
9368 | /* exclude_kernel checked on syscall entry */ | |
9369 | if (!attr->exclude_kernel) | |
9370 | mask |= PERF_SAMPLE_BRANCH_KERNEL; | |
9371 | ||
9372 | if (!attr->exclude_user) | |
9373 | mask |= PERF_SAMPLE_BRANCH_USER; | |
9374 | ||
9375 | if (!attr->exclude_hv) | |
9376 | mask |= PERF_SAMPLE_BRANCH_HV; | |
9377 | /* | |
9378 | * adjust user setting (for HW filter setup) | |
9379 | */ | |
9380 | attr->branch_sample_type = mask; | |
9381 | } | |
e712209a SE |
9382 | /* privileged levels capture (kernel, hv): check permissions */ |
9383 | if ((mask & PERF_SAMPLE_BRANCH_PERM_PLM) | |
2b923c8f SE |
9384 | && perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) |
9385 | return -EACCES; | |
bce38cd5 | 9386 | } |
4018994f | 9387 | |
c5ebcedb | 9388 | if (attr->sample_type & PERF_SAMPLE_REGS_USER) { |
4018994f | 9389 | ret = perf_reg_validate(attr->sample_regs_user); |
c5ebcedb JO |
9390 | if (ret) |
9391 | return ret; | |
9392 | } | |
9393 | ||
9394 | if (attr->sample_type & PERF_SAMPLE_STACK_USER) { | |
9395 | if (!arch_perf_have_user_stack_dump()) | |
9396 | return -ENOSYS; | |
9397 | ||
9398 | /* | |
9399 | * We have __u32 type for the size, but so far | |
9400 | * we can only use __u16 as maximum due to the | |
9401 | * __u16 sample size limit. | |
9402 | */ | |
9403 | if (attr->sample_stack_user >= USHRT_MAX) | |
9404 | ret = -EINVAL; | |
9405 | else if (!IS_ALIGNED(attr->sample_stack_user, sizeof(u64))) | |
9406 | ret = -EINVAL; | |
9407 | } | |
4018994f | 9408 | |
60e2364e SE |
9409 | if (attr->sample_type & PERF_SAMPLE_REGS_INTR) |
9410 | ret = perf_reg_validate(attr->sample_regs_intr); | |
974802ea PZ |
9411 | out: |
9412 | return ret; | |
9413 | ||
9414 | err_size: | |
9415 | put_user(sizeof(*attr), &uattr->size); | |
9416 | ret = -E2BIG; | |
9417 | goto out; | |
9418 | } | |
9419 | ||
ac9721f3 PZ |
9420 | static int |
9421 | perf_event_set_output(struct perf_event *event, struct perf_event *output_event) | |
a4be7c27 | 9422 | { |
b69cf536 | 9423 | struct ring_buffer *rb = NULL; |
a4be7c27 PZ |
9424 | int ret = -EINVAL; |
9425 | ||
ac9721f3 | 9426 | if (!output_event) |
a4be7c27 PZ |
9427 | goto set; |
9428 | ||
ac9721f3 PZ |
9429 | /* don't allow circular references */ |
9430 | if (event == output_event) | |
a4be7c27 PZ |
9431 | goto out; |
9432 | ||
0f139300 PZ |
9433 | /* |
9434 | * Don't allow cross-cpu buffers | |
9435 | */ | |
9436 | if (output_event->cpu != event->cpu) | |
9437 | goto out; | |
9438 | ||
9439 | /* | |
76369139 | 9440 | * If its not a per-cpu rb, it must be the same task. |
0f139300 PZ |
9441 | */ |
9442 | if (output_event->cpu == -1 && output_event->ctx != event->ctx) | |
9443 | goto out; | |
9444 | ||
34f43927 PZ |
9445 | /* |
9446 | * Mixing clocks in the same buffer is trouble you don't need. | |
9447 | */ | |
9448 | if (output_event->clock != event->clock) | |
9449 | goto out; | |
9450 | ||
9ecda41a WN |
9451 | /* |
9452 | * Either writing ring buffer from beginning or from end. | |
9453 | * Mixing is not allowed. | |
9454 | */ | |
9455 | if (is_write_backward(output_event) != is_write_backward(event)) | |
9456 | goto out; | |
9457 | ||
45bfb2e5 PZ |
9458 | /* |
9459 | * If both events generate aux data, they must be on the same PMU | |
9460 | */ | |
9461 | if (has_aux(event) && has_aux(output_event) && | |
9462 | event->pmu != output_event->pmu) | |
9463 | goto out; | |
9464 | ||
a4be7c27 | 9465 | set: |
cdd6c482 | 9466 | mutex_lock(&event->mmap_mutex); |
ac9721f3 PZ |
9467 | /* Can't redirect output if we've got an active mmap() */ |
9468 | if (atomic_read(&event->mmap_count)) | |
9469 | goto unlock; | |
a4be7c27 | 9470 | |
ac9721f3 | 9471 | if (output_event) { |
76369139 FW |
9472 | /* get the rb we want to redirect to */ |
9473 | rb = ring_buffer_get(output_event); | |
9474 | if (!rb) | |
ac9721f3 | 9475 | goto unlock; |
a4be7c27 PZ |
9476 | } |
9477 | ||
b69cf536 | 9478 | ring_buffer_attach(event, rb); |
9bb5d40c | 9479 | |
a4be7c27 | 9480 | ret = 0; |
ac9721f3 PZ |
9481 | unlock: |
9482 | mutex_unlock(&event->mmap_mutex); | |
9483 | ||
a4be7c27 | 9484 | out: |
a4be7c27 PZ |
9485 | return ret; |
9486 | } | |
9487 | ||
f63a8daa PZ |
9488 | static void mutex_lock_double(struct mutex *a, struct mutex *b) |
9489 | { | |
9490 | if (b < a) | |
9491 | swap(a, b); | |
9492 | ||
9493 | mutex_lock(a); | |
9494 | mutex_lock_nested(b, SINGLE_DEPTH_NESTING); | |
9495 | } | |
9496 | ||
34f43927 PZ |
9497 | static int perf_event_set_clock(struct perf_event *event, clockid_t clk_id) |
9498 | { | |
9499 | bool nmi_safe = false; | |
9500 | ||
9501 | switch (clk_id) { | |
9502 | case CLOCK_MONOTONIC: | |
9503 | event->clock = &ktime_get_mono_fast_ns; | |
9504 | nmi_safe = true; | |
9505 | break; | |
9506 | ||
9507 | case CLOCK_MONOTONIC_RAW: | |
9508 | event->clock = &ktime_get_raw_fast_ns; | |
9509 | nmi_safe = true; | |
9510 | break; | |
9511 | ||
9512 | case CLOCK_REALTIME: | |
9513 | event->clock = &ktime_get_real_ns; | |
9514 | break; | |
9515 | ||
9516 | case CLOCK_BOOTTIME: | |
9517 | event->clock = &ktime_get_boot_ns; | |
9518 | break; | |
9519 | ||
9520 | case CLOCK_TAI: | |
9521 | event->clock = &ktime_get_tai_ns; | |
9522 | break; | |
9523 | ||
9524 | default: | |
9525 | return -EINVAL; | |
9526 | } | |
9527 | ||
9528 | if (!nmi_safe && !(event->pmu->capabilities & PERF_PMU_CAP_NO_NMI)) | |
9529 | return -EINVAL; | |
9530 | ||
9531 | return 0; | |
9532 | } | |
9533 | ||
321027c1 PZ |
9534 | /* |
9535 | * Variation on perf_event_ctx_lock_nested(), except we take two context | |
9536 | * mutexes. | |
9537 | */ | |
9538 | static struct perf_event_context * | |
9539 | __perf_event_ctx_lock_double(struct perf_event *group_leader, | |
9540 | struct perf_event_context *ctx) | |
9541 | { | |
9542 | struct perf_event_context *gctx; | |
9543 | ||
9544 | again: | |
9545 | rcu_read_lock(); | |
9546 | gctx = READ_ONCE(group_leader->ctx); | |
9547 | if (!atomic_inc_not_zero(&gctx->refcount)) { | |
9548 | rcu_read_unlock(); | |
9549 | goto again; | |
9550 | } | |
9551 | rcu_read_unlock(); | |
9552 | ||
9553 | mutex_lock_double(&gctx->mutex, &ctx->mutex); | |
9554 | ||
9555 | if (group_leader->ctx != gctx) { | |
9556 | mutex_unlock(&ctx->mutex); | |
9557 | mutex_unlock(&gctx->mutex); | |
9558 | put_ctx(gctx); | |
9559 | goto again; | |
9560 | } | |
9561 | ||
9562 | return gctx; | |
9563 | } | |
9564 | ||
0793a61d | 9565 | /** |
cdd6c482 | 9566 | * sys_perf_event_open - open a performance event, associate it to a task/cpu |
9f66a381 | 9567 | * |
cdd6c482 | 9568 | * @attr_uptr: event_id type attributes for monitoring/sampling |
0793a61d | 9569 | * @pid: target pid |
9f66a381 | 9570 | * @cpu: target cpu |
cdd6c482 | 9571 | * @group_fd: group leader event fd |
0793a61d | 9572 | */ |
cdd6c482 IM |
9573 | SYSCALL_DEFINE5(perf_event_open, |
9574 | struct perf_event_attr __user *, attr_uptr, | |
2743a5b0 | 9575 | pid_t, pid, int, cpu, int, group_fd, unsigned long, flags) |
0793a61d | 9576 | { |
b04243ef PZ |
9577 | struct perf_event *group_leader = NULL, *output_event = NULL; |
9578 | struct perf_event *event, *sibling; | |
cdd6c482 | 9579 | struct perf_event_attr attr; |
f63a8daa | 9580 | struct perf_event_context *ctx, *uninitialized_var(gctx); |
cdd6c482 | 9581 | struct file *event_file = NULL; |
2903ff01 | 9582 | struct fd group = {NULL, 0}; |
38a81da2 | 9583 | struct task_struct *task = NULL; |
89a1e187 | 9584 | struct pmu *pmu; |
ea635c64 | 9585 | int event_fd; |
b04243ef | 9586 | int move_group = 0; |
dc86cabe | 9587 | int err; |
a21b0b35 | 9588 | int f_flags = O_RDWR; |
79dff51e | 9589 | int cgroup_fd = -1; |
0793a61d | 9590 | |
2743a5b0 | 9591 | /* for future expandability... */ |
e5d1367f | 9592 | if (flags & ~PERF_FLAG_ALL) |
2743a5b0 PM |
9593 | return -EINVAL; |
9594 | ||
dc86cabe IM |
9595 | err = perf_copy_attr(attr_uptr, &attr); |
9596 | if (err) | |
9597 | return err; | |
eab656ae | 9598 | |
0764771d PZ |
9599 | if (!attr.exclude_kernel) { |
9600 | if (perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) | |
9601 | return -EACCES; | |
9602 | } | |
9603 | ||
df58ab24 | 9604 | if (attr.freq) { |
cdd6c482 | 9605 | if (attr.sample_freq > sysctl_perf_event_sample_rate) |
df58ab24 | 9606 | return -EINVAL; |
0819b2e3 PZ |
9607 | } else { |
9608 | if (attr.sample_period & (1ULL << 63)) | |
9609 | return -EINVAL; | |
df58ab24 PZ |
9610 | } |
9611 | ||
97c79a38 ACM |
9612 | if (!attr.sample_max_stack) |
9613 | attr.sample_max_stack = sysctl_perf_event_max_stack; | |
9614 | ||
e5d1367f SE |
9615 | /* |
9616 | * In cgroup mode, the pid argument is used to pass the fd | |
9617 | * opened to the cgroup directory in cgroupfs. The cpu argument | |
9618 | * designates the cpu on which to monitor threads from that | |
9619 | * cgroup. | |
9620 | */ | |
9621 | if ((flags & PERF_FLAG_PID_CGROUP) && (pid == -1 || cpu == -1)) | |
9622 | return -EINVAL; | |
9623 | ||
a21b0b35 YD |
9624 | if (flags & PERF_FLAG_FD_CLOEXEC) |
9625 | f_flags |= O_CLOEXEC; | |
9626 | ||
9627 | event_fd = get_unused_fd_flags(f_flags); | |
ea635c64 AV |
9628 | if (event_fd < 0) |
9629 | return event_fd; | |
9630 | ||
ac9721f3 | 9631 | if (group_fd != -1) { |
2903ff01 AV |
9632 | err = perf_fget_light(group_fd, &group); |
9633 | if (err) | |
d14b12d7 | 9634 | goto err_fd; |
2903ff01 | 9635 | group_leader = group.file->private_data; |
ac9721f3 PZ |
9636 | if (flags & PERF_FLAG_FD_OUTPUT) |
9637 | output_event = group_leader; | |
9638 | if (flags & PERF_FLAG_FD_NO_GROUP) | |
9639 | group_leader = NULL; | |
9640 | } | |
9641 | ||
e5d1367f | 9642 | if (pid != -1 && !(flags & PERF_FLAG_PID_CGROUP)) { |
c6be5a5c PZ |
9643 | task = find_lively_task_by_vpid(pid); |
9644 | if (IS_ERR(task)) { | |
9645 | err = PTR_ERR(task); | |
9646 | goto err_group_fd; | |
9647 | } | |
9648 | } | |
9649 | ||
1f4ee503 PZ |
9650 | if (task && group_leader && |
9651 | group_leader->attr.inherit != attr.inherit) { | |
9652 | err = -EINVAL; | |
9653 | goto err_task; | |
9654 | } | |
9655 | ||
fbfc623f YZ |
9656 | get_online_cpus(); |
9657 | ||
79c9ce57 PZ |
9658 | if (task) { |
9659 | err = mutex_lock_interruptible(&task->signal->cred_guard_mutex); | |
9660 | if (err) | |
9661 | goto err_cpus; | |
9662 | ||
9663 | /* | |
9664 | * Reuse ptrace permission checks for now. | |
9665 | * | |
9666 | * We must hold cred_guard_mutex across this and any potential | |
9667 | * perf_install_in_context() call for this new event to | |
9668 | * serialize against exec() altering our credentials (and the | |
9669 | * perf_event_exit_task() that could imply). | |
9670 | */ | |
9671 | err = -EACCES; | |
9672 | if (!ptrace_may_access(task, PTRACE_MODE_READ_REALCREDS)) | |
9673 | goto err_cred; | |
9674 | } | |
9675 | ||
79dff51e MF |
9676 | if (flags & PERF_FLAG_PID_CGROUP) |
9677 | cgroup_fd = pid; | |
9678 | ||
4dc0da86 | 9679 | event = perf_event_alloc(&attr, cpu, task, group_leader, NULL, |
79dff51e | 9680 | NULL, NULL, cgroup_fd); |
d14b12d7 SE |
9681 | if (IS_ERR(event)) { |
9682 | err = PTR_ERR(event); | |
79c9ce57 | 9683 | goto err_cred; |
d14b12d7 SE |
9684 | } |
9685 | ||
53b25335 VW |
9686 | if (is_sampling_event(event)) { |
9687 | if (event->pmu->capabilities & PERF_PMU_CAP_NO_INTERRUPT) { | |
a1396555 | 9688 | err = -EOPNOTSUPP; |
53b25335 VW |
9689 | goto err_alloc; |
9690 | } | |
9691 | } | |
9692 | ||
89a1e187 PZ |
9693 | /* |
9694 | * Special case software events and allow them to be part of | |
9695 | * any hardware group. | |
9696 | */ | |
9697 | pmu = event->pmu; | |
b04243ef | 9698 | |
34f43927 PZ |
9699 | if (attr.use_clockid) { |
9700 | err = perf_event_set_clock(event, attr.clockid); | |
9701 | if (err) | |
9702 | goto err_alloc; | |
9703 | } | |
9704 | ||
4ff6a8de DCC |
9705 | if (pmu->task_ctx_nr == perf_sw_context) |
9706 | event->event_caps |= PERF_EV_CAP_SOFTWARE; | |
9707 | ||
b04243ef PZ |
9708 | if (group_leader && |
9709 | (is_software_event(event) != is_software_event(group_leader))) { | |
9710 | if (is_software_event(event)) { | |
9711 | /* | |
9712 | * If event and group_leader are not both a software | |
9713 | * event, and event is, then group leader is not. | |
9714 | * | |
9715 | * Allow the addition of software events to !software | |
9716 | * groups, this is safe because software events never | |
9717 | * fail to schedule. | |
9718 | */ | |
9719 | pmu = group_leader->pmu; | |
9720 | } else if (is_software_event(group_leader) && | |
4ff6a8de | 9721 | (group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { |
b04243ef PZ |
9722 | /* |
9723 | * In case the group is a pure software group, and we | |
9724 | * try to add a hardware event, move the whole group to | |
9725 | * the hardware context. | |
9726 | */ | |
9727 | move_group = 1; | |
9728 | } | |
9729 | } | |
89a1e187 PZ |
9730 | |
9731 | /* | |
9732 | * Get the target context (task or percpu): | |
9733 | */ | |
4af57ef2 | 9734 | ctx = find_get_context(pmu, task, event); |
89a1e187 PZ |
9735 | if (IS_ERR(ctx)) { |
9736 | err = PTR_ERR(ctx); | |
c6be5a5c | 9737 | goto err_alloc; |
89a1e187 PZ |
9738 | } |
9739 | ||
bed5b25a AS |
9740 | if ((pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE) && group_leader) { |
9741 | err = -EBUSY; | |
9742 | goto err_context; | |
9743 | } | |
9744 | ||
ccff286d | 9745 | /* |
cdd6c482 | 9746 | * Look up the group leader (we will attach this event to it): |
04289bb9 | 9747 | */ |
ac9721f3 | 9748 | if (group_leader) { |
dc86cabe | 9749 | err = -EINVAL; |
04289bb9 | 9750 | |
04289bb9 | 9751 | /* |
ccff286d IM |
9752 | * Do not allow a recursive hierarchy (this new sibling |
9753 | * becoming part of another group-sibling): | |
9754 | */ | |
9755 | if (group_leader->group_leader != group_leader) | |
c3f00c70 | 9756 | goto err_context; |
34f43927 PZ |
9757 | |
9758 | /* All events in a group should have the same clock */ | |
9759 | if (group_leader->clock != event->clock) | |
9760 | goto err_context; | |
9761 | ||
ccff286d IM |
9762 | /* |
9763 | * Do not allow to attach to a group in a different | |
9764 | * task or CPU context: | |
04289bb9 | 9765 | */ |
b04243ef | 9766 | if (move_group) { |
c3c87e77 PZ |
9767 | /* |
9768 | * Make sure we're both on the same task, or both | |
9769 | * per-cpu events. | |
9770 | */ | |
9771 | if (group_leader->ctx->task != ctx->task) | |
9772 | goto err_context; | |
9773 | ||
9774 | /* | |
9775 | * Make sure we're both events for the same CPU; | |
9776 | * grouping events for different CPUs is broken; since | |
9777 | * you can never concurrently schedule them anyhow. | |
9778 | */ | |
9779 | if (group_leader->cpu != event->cpu) | |
b04243ef PZ |
9780 | goto err_context; |
9781 | } else { | |
9782 | if (group_leader->ctx != ctx) | |
9783 | goto err_context; | |
9784 | } | |
9785 | ||
3b6f9e5c PM |
9786 | /* |
9787 | * Only a group leader can be exclusive or pinned | |
9788 | */ | |
0d48696f | 9789 | if (attr.exclusive || attr.pinned) |
c3f00c70 | 9790 | goto err_context; |
ac9721f3 PZ |
9791 | } |
9792 | ||
9793 | if (output_event) { | |
9794 | err = perf_event_set_output(event, output_event); | |
9795 | if (err) | |
c3f00c70 | 9796 | goto err_context; |
ac9721f3 | 9797 | } |
0793a61d | 9798 | |
a21b0b35 YD |
9799 | event_file = anon_inode_getfile("[perf_event]", &perf_fops, event, |
9800 | f_flags); | |
ea635c64 AV |
9801 | if (IS_ERR(event_file)) { |
9802 | err = PTR_ERR(event_file); | |
201c2f85 | 9803 | event_file = NULL; |
c3f00c70 | 9804 | goto err_context; |
ea635c64 | 9805 | } |
9b51f66d | 9806 | |
b04243ef | 9807 | if (move_group) { |
321027c1 PZ |
9808 | gctx = __perf_event_ctx_lock_double(group_leader, ctx); |
9809 | ||
84c4e620 PZ |
9810 | if (gctx->task == TASK_TOMBSTONE) { |
9811 | err = -ESRCH; | |
9812 | goto err_locked; | |
9813 | } | |
321027c1 PZ |
9814 | |
9815 | /* | |
9816 | * Check if we raced against another sys_perf_event_open() call | |
9817 | * moving the software group underneath us. | |
9818 | */ | |
9819 | if (!(group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { | |
9820 | /* | |
9821 | * If someone moved the group out from under us, check | |
9822 | * if this new event wound up on the same ctx, if so | |
9823 | * its the regular !move_group case, otherwise fail. | |
9824 | */ | |
9825 | if (gctx != ctx) { | |
9826 | err = -EINVAL; | |
9827 | goto err_locked; | |
9828 | } else { | |
9829 | perf_event_ctx_unlock(group_leader, gctx); | |
9830 | move_group = 0; | |
9831 | } | |
9832 | } | |
f55fc2a5 PZ |
9833 | } else { |
9834 | mutex_lock(&ctx->mutex); | |
9835 | } | |
9836 | ||
84c4e620 PZ |
9837 | if (ctx->task == TASK_TOMBSTONE) { |
9838 | err = -ESRCH; | |
9839 | goto err_locked; | |
9840 | } | |
9841 | ||
a723968c PZ |
9842 | if (!perf_event_validate_size(event)) { |
9843 | err = -E2BIG; | |
9844 | goto err_locked; | |
9845 | } | |
9846 | ||
f55fc2a5 PZ |
9847 | /* |
9848 | * Must be under the same ctx::mutex as perf_install_in_context(), | |
9849 | * because we need to serialize with concurrent event creation. | |
9850 | */ | |
9851 | if (!exclusive_event_installable(event, ctx)) { | |
9852 | /* exclusive and group stuff are assumed mutually exclusive */ | |
9853 | WARN_ON_ONCE(move_group); | |
f63a8daa | 9854 | |
f55fc2a5 PZ |
9855 | err = -EBUSY; |
9856 | goto err_locked; | |
9857 | } | |
f63a8daa | 9858 | |
f55fc2a5 PZ |
9859 | WARN_ON_ONCE(ctx->parent_ctx); |
9860 | ||
79c9ce57 PZ |
9861 | /* |
9862 | * This is the point on no return; we cannot fail hereafter. This is | |
9863 | * where we start modifying current state. | |
9864 | */ | |
9865 | ||
f55fc2a5 | 9866 | if (move_group) { |
f63a8daa PZ |
9867 | /* |
9868 | * See perf_event_ctx_lock() for comments on the details | |
9869 | * of swizzling perf_event::ctx. | |
9870 | */ | |
45a0e07a | 9871 | perf_remove_from_context(group_leader, 0); |
0231bb53 | 9872 | |
b04243ef PZ |
9873 | list_for_each_entry(sibling, &group_leader->sibling_list, |
9874 | group_entry) { | |
45a0e07a | 9875 | perf_remove_from_context(sibling, 0); |
b04243ef PZ |
9876 | put_ctx(gctx); |
9877 | } | |
b04243ef | 9878 | |
f63a8daa PZ |
9879 | /* |
9880 | * Wait for everybody to stop referencing the events through | |
9881 | * the old lists, before installing it on new lists. | |
9882 | */ | |
0cda4c02 | 9883 | synchronize_rcu(); |
f63a8daa | 9884 | |
8f95b435 PZI |
9885 | /* |
9886 | * Install the group siblings before the group leader. | |
9887 | * | |
9888 | * Because a group leader will try and install the entire group | |
9889 | * (through the sibling list, which is still in-tact), we can | |
9890 | * end up with siblings installed in the wrong context. | |
9891 | * | |
9892 | * By installing siblings first we NO-OP because they're not | |
9893 | * reachable through the group lists. | |
9894 | */ | |
b04243ef PZ |
9895 | list_for_each_entry(sibling, &group_leader->sibling_list, |
9896 | group_entry) { | |
8f95b435 | 9897 | perf_event__state_init(sibling); |
9fc81d87 | 9898 | perf_install_in_context(ctx, sibling, sibling->cpu); |
b04243ef PZ |
9899 | get_ctx(ctx); |
9900 | } | |
8f95b435 PZI |
9901 | |
9902 | /* | |
9903 | * Removing from the context ends up with disabled | |
9904 | * event. What we want here is event in the initial | |
9905 | * startup state, ready to be add into new context. | |
9906 | */ | |
9907 | perf_event__state_init(group_leader); | |
9908 | perf_install_in_context(ctx, group_leader, group_leader->cpu); | |
9909 | get_ctx(ctx); | |
b04243ef | 9910 | |
f55fc2a5 PZ |
9911 | /* |
9912 | * Now that all events are installed in @ctx, nothing | |
9913 | * references @gctx anymore, so drop the last reference we have | |
9914 | * on it. | |
9915 | */ | |
9916 | put_ctx(gctx); | |
bed5b25a AS |
9917 | } |
9918 | ||
f73e22ab PZ |
9919 | /* |
9920 | * Precalculate sample_data sizes; do while holding ctx::mutex such | |
9921 | * that we're serialized against further additions and before | |
9922 | * perf_install_in_context() which is the point the event is active and | |
9923 | * can use these values. | |
9924 | */ | |
9925 | perf_event__header_size(event); | |
9926 | perf_event__id_header_size(event); | |
9927 | ||
78cd2c74 PZ |
9928 | event->owner = current; |
9929 | ||
e2d37cd2 | 9930 | perf_install_in_context(ctx, event, event->cpu); |
fe4b04fa | 9931 | perf_unpin_context(ctx); |
f63a8daa | 9932 | |
f55fc2a5 | 9933 | if (move_group) |
321027c1 | 9934 | perf_event_ctx_unlock(group_leader, gctx); |
d859e29f | 9935 | mutex_unlock(&ctx->mutex); |
9b51f66d | 9936 | |
79c9ce57 PZ |
9937 | if (task) { |
9938 | mutex_unlock(&task->signal->cred_guard_mutex); | |
9939 | put_task_struct(task); | |
9940 | } | |
9941 | ||
fbfc623f YZ |
9942 | put_online_cpus(); |
9943 | ||
cdd6c482 IM |
9944 | mutex_lock(¤t->perf_event_mutex); |
9945 | list_add_tail(&event->owner_entry, ¤t->perf_event_list); | |
9946 | mutex_unlock(¤t->perf_event_mutex); | |
082ff5a2 | 9947 | |
8a49542c PZ |
9948 | /* |
9949 | * Drop the reference on the group_event after placing the | |
9950 | * new event on the sibling_list. This ensures destruction | |
9951 | * of the group leader will find the pointer to itself in | |
9952 | * perf_group_detach(). | |
9953 | */ | |
2903ff01 | 9954 | fdput(group); |
ea635c64 AV |
9955 | fd_install(event_fd, event_file); |
9956 | return event_fd; | |
0793a61d | 9957 | |
f55fc2a5 PZ |
9958 | err_locked: |
9959 | if (move_group) | |
321027c1 | 9960 | perf_event_ctx_unlock(group_leader, gctx); |
f55fc2a5 PZ |
9961 | mutex_unlock(&ctx->mutex); |
9962 | /* err_file: */ | |
9963 | fput(event_file); | |
c3f00c70 | 9964 | err_context: |
fe4b04fa | 9965 | perf_unpin_context(ctx); |
ea635c64 | 9966 | put_ctx(ctx); |
c6be5a5c | 9967 | err_alloc: |
13005627 PZ |
9968 | /* |
9969 | * If event_file is set, the fput() above will have called ->release() | |
9970 | * and that will take care of freeing the event. | |
9971 | */ | |
9972 | if (!event_file) | |
9973 | free_event(event); | |
79c9ce57 PZ |
9974 | err_cred: |
9975 | if (task) | |
9976 | mutex_unlock(&task->signal->cred_guard_mutex); | |
1f4ee503 | 9977 | err_cpus: |
fbfc623f | 9978 | put_online_cpus(); |
1f4ee503 | 9979 | err_task: |
e7d0bc04 PZ |
9980 | if (task) |
9981 | put_task_struct(task); | |
89a1e187 | 9982 | err_group_fd: |
2903ff01 | 9983 | fdput(group); |
ea635c64 AV |
9984 | err_fd: |
9985 | put_unused_fd(event_fd); | |
dc86cabe | 9986 | return err; |
0793a61d TG |
9987 | } |
9988 | ||
fb0459d7 AV |
9989 | /** |
9990 | * perf_event_create_kernel_counter | |
9991 | * | |
9992 | * @attr: attributes of the counter to create | |
9993 | * @cpu: cpu in which the counter is bound | |
38a81da2 | 9994 | * @task: task to profile (NULL for percpu) |
fb0459d7 AV |
9995 | */ |
9996 | struct perf_event * | |
9997 | perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, | |
38a81da2 | 9998 | struct task_struct *task, |
4dc0da86 AK |
9999 | perf_overflow_handler_t overflow_handler, |
10000 | void *context) | |
fb0459d7 | 10001 | { |
fb0459d7 | 10002 | struct perf_event_context *ctx; |
c3f00c70 | 10003 | struct perf_event *event; |
fb0459d7 | 10004 | int err; |
d859e29f | 10005 | |
fb0459d7 AV |
10006 | /* |
10007 | * Get the target context (task or percpu): | |
10008 | */ | |
d859e29f | 10009 | |
4dc0da86 | 10010 | event = perf_event_alloc(attr, cpu, task, NULL, NULL, |
79dff51e | 10011 | overflow_handler, context, -1); |
c3f00c70 PZ |
10012 | if (IS_ERR(event)) { |
10013 | err = PTR_ERR(event); | |
10014 | goto err; | |
10015 | } | |
d859e29f | 10016 | |
f8697762 | 10017 | /* Mark owner so we could distinguish it from user events. */ |
63b6da39 | 10018 | event->owner = TASK_TOMBSTONE; |
f8697762 | 10019 | |
4af57ef2 | 10020 | ctx = find_get_context(event->pmu, task, event); |
c6567f64 FW |
10021 | if (IS_ERR(ctx)) { |
10022 | err = PTR_ERR(ctx); | |
c3f00c70 | 10023 | goto err_free; |
d859e29f | 10024 | } |
fb0459d7 | 10025 | |
fb0459d7 AV |
10026 | WARN_ON_ONCE(ctx->parent_ctx); |
10027 | mutex_lock(&ctx->mutex); | |
84c4e620 PZ |
10028 | if (ctx->task == TASK_TOMBSTONE) { |
10029 | err = -ESRCH; | |
10030 | goto err_unlock; | |
10031 | } | |
10032 | ||
bed5b25a | 10033 | if (!exclusive_event_installable(event, ctx)) { |
bed5b25a | 10034 | err = -EBUSY; |
84c4e620 | 10035 | goto err_unlock; |
bed5b25a AS |
10036 | } |
10037 | ||
fb0459d7 | 10038 | perf_install_in_context(ctx, event, cpu); |
fe4b04fa | 10039 | perf_unpin_context(ctx); |
fb0459d7 AV |
10040 | mutex_unlock(&ctx->mutex); |
10041 | ||
fb0459d7 AV |
10042 | return event; |
10043 | ||
84c4e620 PZ |
10044 | err_unlock: |
10045 | mutex_unlock(&ctx->mutex); | |
10046 | perf_unpin_context(ctx); | |
10047 | put_ctx(ctx); | |
c3f00c70 PZ |
10048 | err_free: |
10049 | free_event(event); | |
10050 | err: | |
c6567f64 | 10051 | return ERR_PTR(err); |
9b51f66d | 10052 | } |
fb0459d7 | 10053 | EXPORT_SYMBOL_GPL(perf_event_create_kernel_counter); |
9b51f66d | 10054 | |
0cda4c02 YZ |
10055 | void perf_pmu_migrate_context(struct pmu *pmu, int src_cpu, int dst_cpu) |
10056 | { | |
10057 | struct perf_event_context *src_ctx; | |
10058 | struct perf_event_context *dst_ctx; | |
10059 | struct perf_event *event, *tmp; | |
10060 | LIST_HEAD(events); | |
10061 | ||
10062 | src_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, src_cpu)->ctx; | |
10063 | dst_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, dst_cpu)->ctx; | |
10064 | ||
f63a8daa PZ |
10065 | /* |
10066 | * See perf_event_ctx_lock() for comments on the details | |
10067 | * of swizzling perf_event::ctx. | |
10068 | */ | |
10069 | mutex_lock_double(&src_ctx->mutex, &dst_ctx->mutex); | |
0cda4c02 YZ |
10070 | list_for_each_entry_safe(event, tmp, &src_ctx->event_list, |
10071 | event_entry) { | |
45a0e07a | 10072 | perf_remove_from_context(event, 0); |
9a545de0 | 10073 | unaccount_event_cpu(event, src_cpu); |
0cda4c02 | 10074 | put_ctx(src_ctx); |
9886167d | 10075 | list_add(&event->migrate_entry, &events); |
0cda4c02 | 10076 | } |
0cda4c02 | 10077 | |
8f95b435 PZI |
10078 | /* |
10079 | * Wait for the events to quiesce before re-instating them. | |
10080 | */ | |
0cda4c02 YZ |
10081 | synchronize_rcu(); |
10082 | ||
8f95b435 PZI |
10083 | /* |
10084 | * Re-instate events in 2 passes. | |
10085 | * | |
10086 | * Skip over group leaders and only install siblings on this first | |
10087 | * pass, siblings will not get enabled without a leader, however a | |
10088 | * leader will enable its siblings, even if those are still on the old | |
10089 | * context. | |
10090 | */ | |
10091 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { | |
10092 | if (event->group_leader == event) | |
10093 | continue; | |
10094 | ||
10095 | list_del(&event->migrate_entry); | |
10096 | if (event->state >= PERF_EVENT_STATE_OFF) | |
10097 | event->state = PERF_EVENT_STATE_INACTIVE; | |
10098 | account_event_cpu(event, dst_cpu); | |
10099 | perf_install_in_context(dst_ctx, event, dst_cpu); | |
10100 | get_ctx(dst_ctx); | |
10101 | } | |
10102 | ||
10103 | /* | |
10104 | * Once all the siblings are setup properly, install the group leaders | |
10105 | * to make it go. | |
10106 | */ | |
9886167d PZ |
10107 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { |
10108 | list_del(&event->migrate_entry); | |
0cda4c02 YZ |
10109 | if (event->state >= PERF_EVENT_STATE_OFF) |
10110 | event->state = PERF_EVENT_STATE_INACTIVE; | |
9a545de0 | 10111 | account_event_cpu(event, dst_cpu); |
0cda4c02 YZ |
10112 | perf_install_in_context(dst_ctx, event, dst_cpu); |
10113 | get_ctx(dst_ctx); | |
10114 | } | |
10115 | mutex_unlock(&dst_ctx->mutex); | |
f63a8daa | 10116 | mutex_unlock(&src_ctx->mutex); |
0cda4c02 YZ |
10117 | } |
10118 | EXPORT_SYMBOL_GPL(perf_pmu_migrate_context); | |
10119 | ||
cdd6c482 | 10120 | static void sync_child_event(struct perf_event *child_event, |
38b200d6 | 10121 | struct task_struct *child) |
d859e29f | 10122 | { |
cdd6c482 | 10123 | struct perf_event *parent_event = child_event->parent; |
8bc20959 | 10124 | u64 child_val; |
d859e29f | 10125 | |
cdd6c482 IM |
10126 | if (child_event->attr.inherit_stat) |
10127 | perf_event_read_event(child_event, child); | |
38b200d6 | 10128 | |
b5e58793 | 10129 | child_val = perf_event_count(child_event); |
d859e29f PM |
10130 | |
10131 | /* | |
10132 | * Add back the child's count to the parent's count: | |
10133 | */ | |
a6e6dea6 | 10134 | atomic64_add(child_val, &parent_event->child_count); |
cdd6c482 IM |
10135 | atomic64_add(child_event->total_time_enabled, |
10136 | &parent_event->child_total_time_enabled); | |
10137 | atomic64_add(child_event->total_time_running, | |
10138 | &parent_event->child_total_time_running); | |
d859e29f PM |
10139 | } |
10140 | ||
9b51f66d | 10141 | static void |
8ba289b8 PZ |
10142 | perf_event_exit_event(struct perf_event *child_event, |
10143 | struct perf_event_context *child_ctx, | |
10144 | struct task_struct *child) | |
9b51f66d | 10145 | { |
8ba289b8 PZ |
10146 | struct perf_event *parent_event = child_event->parent; |
10147 | ||
1903d50c PZ |
10148 | /* |
10149 | * Do not destroy the 'original' grouping; because of the context | |
10150 | * switch optimization the original events could've ended up in a | |
10151 | * random child task. | |
10152 | * | |
10153 | * If we were to destroy the original group, all group related | |
10154 | * operations would cease to function properly after this random | |
10155 | * child dies. | |
10156 | * | |
10157 | * Do destroy all inherited groups, we don't care about those | |
10158 | * and being thorough is better. | |
10159 | */ | |
32132a3d PZ |
10160 | raw_spin_lock_irq(&child_ctx->lock); |
10161 | WARN_ON_ONCE(child_ctx->is_active); | |
10162 | ||
8ba289b8 | 10163 | if (parent_event) |
32132a3d PZ |
10164 | perf_group_detach(child_event); |
10165 | list_del_event(child_event, child_ctx); | |
a69b0ca4 | 10166 | child_event->state = PERF_EVENT_STATE_EXIT; /* is_event_hup() */ |
32132a3d | 10167 | raw_spin_unlock_irq(&child_ctx->lock); |
0cc0c027 | 10168 | |
9b51f66d | 10169 | /* |
8ba289b8 | 10170 | * Parent events are governed by their filedesc, retain them. |
9b51f66d | 10171 | */ |
8ba289b8 | 10172 | if (!parent_event) { |
179033b3 | 10173 | perf_event_wakeup(child_event); |
8ba289b8 | 10174 | return; |
4bcf349a | 10175 | } |
8ba289b8 PZ |
10176 | /* |
10177 | * Child events can be cleaned up. | |
10178 | */ | |
10179 | ||
10180 | sync_child_event(child_event, child); | |
10181 | ||
10182 | /* | |
10183 | * Remove this event from the parent's list | |
10184 | */ | |
10185 | WARN_ON_ONCE(parent_event->ctx->parent_ctx); | |
10186 | mutex_lock(&parent_event->child_mutex); | |
10187 | list_del_init(&child_event->child_list); | |
10188 | mutex_unlock(&parent_event->child_mutex); | |
10189 | ||
10190 | /* | |
10191 | * Kick perf_poll() for is_event_hup(). | |
10192 | */ | |
10193 | perf_event_wakeup(parent_event); | |
10194 | free_event(child_event); | |
10195 | put_event(parent_event); | |
9b51f66d IM |
10196 | } |
10197 | ||
8dc85d54 | 10198 | static void perf_event_exit_task_context(struct task_struct *child, int ctxn) |
9b51f66d | 10199 | { |
211de6eb | 10200 | struct perf_event_context *child_ctx, *clone_ctx = NULL; |
63b6da39 | 10201 | struct perf_event *child_event, *next; |
63b6da39 PZ |
10202 | |
10203 | WARN_ON_ONCE(child != current); | |
9b51f66d | 10204 | |
6a3351b6 | 10205 | child_ctx = perf_pin_task_context(child, ctxn); |
63b6da39 | 10206 | if (!child_ctx) |
9b51f66d IM |
10207 | return; |
10208 | ||
ad3a37de | 10209 | /* |
6a3351b6 PZ |
10210 | * In order to reduce the amount of tricky in ctx tear-down, we hold |
10211 | * ctx::mutex over the entire thing. This serializes against almost | |
10212 | * everything that wants to access the ctx. | |
10213 | * | |
10214 | * The exception is sys_perf_event_open() / | |
10215 | * perf_event_create_kernel_count() which does find_get_context() | |
10216 | * without ctx::mutex (it cannot because of the move_group double mutex | |
10217 | * lock thing). See the comments in perf_install_in_context(). | |
ad3a37de | 10218 | */ |
6a3351b6 | 10219 | mutex_lock(&child_ctx->mutex); |
c93f7669 PM |
10220 | |
10221 | /* | |
6a3351b6 PZ |
10222 | * In a single ctx::lock section, de-schedule the events and detach the |
10223 | * context from the task such that we cannot ever get it scheduled back | |
10224 | * in. | |
c93f7669 | 10225 | */ |
6a3351b6 | 10226 | raw_spin_lock_irq(&child_ctx->lock); |
63b6da39 | 10227 | task_ctx_sched_out(__get_cpu_context(child_ctx), child_ctx); |
4a1c0f26 | 10228 | |
71a851b4 | 10229 | /* |
63b6da39 PZ |
10230 | * Now that the context is inactive, destroy the task <-> ctx relation |
10231 | * and mark the context dead. | |
71a851b4 | 10232 | */ |
63b6da39 PZ |
10233 | RCU_INIT_POINTER(child->perf_event_ctxp[ctxn], NULL); |
10234 | put_ctx(child_ctx); /* cannot be last */ | |
10235 | WRITE_ONCE(child_ctx->task, TASK_TOMBSTONE); | |
10236 | put_task_struct(current); /* cannot be last */ | |
4a1c0f26 | 10237 | |
211de6eb | 10238 | clone_ctx = unclone_ctx(child_ctx); |
6a3351b6 | 10239 | raw_spin_unlock_irq(&child_ctx->lock); |
9f498cc5 | 10240 | |
211de6eb PZ |
10241 | if (clone_ctx) |
10242 | put_ctx(clone_ctx); | |
4a1c0f26 | 10243 | |
9f498cc5 | 10244 | /* |
cdd6c482 IM |
10245 | * Report the task dead after unscheduling the events so that we |
10246 | * won't get any samples after PERF_RECORD_EXIT. We can however still | |
10247 | * get a few PERF_RECORD_READ events. | |
9f498cc5 | 10248 | */ |
cdd6c482 | 10249 | perf_event_task(child, child_ctx, 0); |
a63eaf34 | 10250 | |
ebf905fc | 10251 | list_for_each_entry_safe(child_event, next, &child_ctx->event_list, event_entry) |
8ba289b8 | 10252 | perf_event_exit_event(child_event, child_ctx, child); |
8bc20959 | 10253 | |
a63eaf34 PM |
10254 | mutex_unlock(&child_ctx->mutex); |
10255 | ||
10256 | put_ctx(child_ctx); | |
9b51f66d IM |
10257 | } |
10258 | ||
8dc85d54 PZ |
10259 | /* |
10260 | * When a child task exits, feed back event values to parent events. | |
79c9ce57 PZ |
10261 | * |
10262 | * Can be called with cred_guard_mutex held when called from | |
10263 | * install_exec_creds(). | |
8dc85d54 PZ |
10264 | */ |
10265 | void perf_event_exit_task(struct task_struct *child) | |
10266 | { | |
8882135b | 10267 | struct perf_event *event, *tmp; |
8dc85d54 PZ |
10268 | int ctxn; |
10269 | ||
8882135b PZ |
10270 | mutex_lock(&child->perf_event_mutex); |
10271 | list_for_each_entry_safe(event, tmp, &child->perf_event_list, | |
10272 | owner_entry) { | |
10273 | list_del_init(&event->owner_entry); | |
10274 | ||
10275 | /* | |
10276 | * Ensure the list deletion is visible before we clear | |
10277 | * the owner, closes a race against perf_release() where | |
10278 | * we need to serialize on the owner->perf_event_mutex. | |
10279 | */ | |
f47c02c0 | 10280 | smp_store_release(&event->owner, NULL); |
8882135b PZ |
10281 | } |
10282 | mutex_unlock(&child->perf_event_mutex); | |
10283 | ||
8dc85d54 PZ |
10284 | for_each_task_context_nr(ctxn) |
10285 | perf_event_exit_task_context(child, ctxn); | |
4e93ad60 JO |
10286 | |
10287 | /* | |
10288 | * The perf_event_exit_task_context calls perf_event_task | |
10289 | * with child's task_ctx, which generates EXIT events for | |
10290 | * child contexts and sets child->perf_event_ctxp[] to NULL. | |
10291 | * At this point we need to send EXIT events to cpu contexts. | |
10292 | */ | |
10293 | perf_event_task(child, NULL, 0); | |
8dc85d54 PZ |
10294 | } |
10295 | ||
889ff015 FW |
10296 | static void perf_free_event(struct perf_event *event, |
10297 | struct perf_event_context *ctx) | |
10298 | { | |
10299 | struct perf_event *parent = event->parent; | |
10300 | ||
10301 | if (WARN_ON_ONCE(!parent)) | |
10302 | return; | |
10303 | ||
10304 | mutex_lock(&parent->child_mutex); | |
10305 | list_del_init(&event->child_list); | |
10306 | mutex_unlock(&parent->child_mutex); | |
10307 | ||
a6fa941d | 10308 | put_event(parent); |
889ff015 | 10309 | |
652884fe | 10310 | raw_spin_lock_irq(&ctx->lock); |
8a49542c | 10311 | perf_group_detach(event); |
889ff015 | 10312 | list_del_event(event, ctx); |
652884fe | 10313 | raw_spin_unlock_irq(&ctx->lock); |
889ff015 FW |
10314 | free_event(event); |
10315 | } | |
10316 | ||
bbbee908 | 10317 | /* |
652884fe | 10318 | * Free an unexposed, unused context as created by inheritance by |
8dc85d54 | 10319 | * perf_event_init_task below, used by fork() in case of fail. |
652884fe PZ |
10320 | * |
10321 | * Not all locks are strictly required, but take them anyway to be nice and | |
10322 | * help out with the lockdep assertions. | |
bbbee908 | 10323 | */ |
cdd6c482 | 10324 | void perf_event_free_task(struct task_struct *task) |
bbbee908 | 10325 | { |
8dc85d54 | 10326 | struct perf_event_context *ctx; |
cdd6c482 | 10327 | struct perf_event *event, *tmp; |
8dc85d54 | 10328 | int ctxn; |
bbbee908 | 10329 | |
8dc85d54 PZ |
10330 | for_each_task_context_nr(ctxn) { |
10331 | ctx = task->perf_event_ctxp[ctxn]; | |
10332 | if (!ctx) | |
10333 | continue; | |
bbbee908 | 10334 | |
8dc85d54 | 10335 | mutex_lock(&ctx->mutex); |
bbbee908 | 10336 | again: |
8dc85d54 PZ |
10337 | list_for_each_entry_safe(event, tmp, &ctx->pinned_groups, |
10338 | group_entry) | |
10339 | perf_free_event(event, ctx); | |
bbbee908 | 10340 | |
8dc85d54 PZ |
10341 | list_for_each_entry_safe(event, tmp, &ctx->flexible_groups, |
10342 | group_entry) | |
10343 | perf_free_event(event, ctx); | |
bbbee908 | 10344 | |
8dc85d54 PZ |
10345 | if (!list_empty(&ctx->pinned_groups) || |
10346 | !list_empty(&ctx->flexible_groups)) | |
10347 | goto again; | |
bbbee908 | 10348 | |
8dc85d54 | 10349 | mutex_unlock(&ctx->mutex); |
bbbee908 | 10350 | |
8dc85d54 PZ |
10351 | put_ctx(ctx); |
10352 | } | |
889ff015 FW |
10353 | } |
10354 | ||
4e231c79 PZ |
10355 | void perf_event_delayed_put(struct task_struct *task) |
10356 | { | |
10357 | int ctxn; | |
10358 | ||
10359 | for_each_task_context_nr(ctxn) | |
10360 | WARN_ON_ONCE(task->perf_event_ctxp[ctxn]); | |
10361 | } | |
10362 | ||
e03e7ee3 | 10363 | struct file *perf_event_get(unsigned int fd) |
ffe8690c | 10364 | { |
e03e7ee3 | 10365 | struct file *file; |
ffe8690c | 10366 | |
e03e7ee3 AS |
10367 | file = fget_raw(fd); |
10368 | if (!file) | |
10369 | return ERR_PTR(-EBADF); | |
ffe8690c | 10370 | |
e03e7ee3 AS |
10371 | if (file->f_op != &perf_fops) { |
10372 | fput(file); | |
10373 | return ERR_PTR(-EBADF); | |
10374 | } | |
ffe8690c | 10375 | |
e03e7ee3 | 10376 | return file; |
ffe8690c KX |
10377 | } |
10378 | ||
10379 | const struct perf_event_attr *perf_event_attrs(struct perf_event *event) | |
10380 | { | |
10381 | if (!event) | |
10382 | return ERR_PTR(-EINVAL); | |
10383 | ||
10384 | return &event->attr; | |
10385 | } | |
10386 | ||
97dee4f3 PZ |
10387 | /* |
10388 | * inherit a event from parent task to child task: | |
10389 | */ | |
10390 | static struct perf_event * | |
10391 | inherit_event(struct perf_event *parent_event, | |
10392 | struct task_struct *parent, | |
10393 | struct perf_event_context *parent_ctx, | |
10394 | struct task_struct *child, | |
10395 | struct perf_event *group_leader, | |
10396 | struct perf_event_context *child_ctx) | |
10397 | { | |
1929def9 | 10398 | enum perf_event_active_state parent_state = parent_event->state; |
97dee4f3 | 10399 | struct perf_event *child_event; |
cee010ec | 10400 | unsigned long flags; |
97dee4f3 PZ |
10401 | |
10402 | /* | |
10403 | * Instead of creating recursive hierarchies of events, | |
10404 | * we link inherited events back to the original parent, | |
10405 | * which has a filp for sure, which we use as the reference | |
10406 | * count: | |
10407 | */ | |
10408 | if (parent_event->parent) | |
10409 | parent_event = parent_event->parent; | |
10410 | ||
10411 | child_event = perf_event_alloc(&parent_event->attr, | |
10412 | parent_event->cpu, | |
d580ff86 | 10413 | child, |
97dee4f3 | 10414 | group_leader, parent_event, |
79dff51e | 10415 | NULL, NULL, -1); |
97dee4f3 PZ |
10416 | if (IS_ERR(child_event)) |
10417 | return child_event; | |
a6fa941d | 10418 | |
c6e5b732 PZ |
10419 | /* |
10420 | * is_orphaned_event() and list_add_tail(&parent_event->child_list) | |
10421 | * must be under the same lock in order to serialize against | |
10422 | * perf_event_release_kernel(), such that either we must observe | |
10423 | * is_orphaned_event() or they will observe us on the child_list. | |
10424 | */ | |
10425 | mutex_lock(&parent_event->child_mutex); | |
fadfe7be JO |
10426 | if (is_orphaned_event(parent_event) || |
10427 | !atomic_long_inc_not_zero(&parent_event->refcount)) { | |
c6e5b732 | 10428 | mutex_unlock(&parent_event->child_mutex); |
a6fa941d AV |
10429 | free_event(child_event); |
10430 | return NULL; | |
10431 | } | |
10432 | ||
97dee4f3 PZ |
10433 | get_ctx(child_ctx); |
10434 | ||
10435 | /* | |
10436 | * Make the child state follow the state of the parent event, | |
10437 | * not its attr.disabled bit. We hold the parent's mutex, | |
10438 | * so we won't race with perf_event_{en, dis}able_family. | |
10439 | */ | |
1929def9 | 10440 | if (parent_state >= PERF_EVENT_STATE_INACTIVE) |
97dee4f3 PZ |
10441 | child_event->state = PERF_EVENT_STATE_INACTIVE; |
10442 | else | |
10443 | child_event->state = PERF_EVENT_STATE_OFF; | |
10444 | ||
10445 | if (parent_event->attr.freq) { | |
10446 | u64 sample_period = parent_event->hw.sample_period; | |
10447 | struct hw_perf_event *hwc = &child_event->hw; | |
10448 | ||
10449 | hwc->sample_period = sample_period; | |
10450 | hwc->last_period = sample_period; | |
10451 | ||
10452 | local64_set(&hwc->period_left, sample_period); | |
10453 | } | |
10454 | ||
10455 | child_event->ctx = child_ctx; | |
10456 | child_event->overflow_handler = parent_event->overflow_handler; | |
4dc0da86 AK |
10457 | child_event->overflow_handler_context |
10458 | = parent_event->overflow_handler_context; | |
97dee4f3 | 10459 | |
614b6780 TG |
10460 | /* |
10461 | * Precalculate sample_data sizes | |
10462 | */ | |
10463 | perf_event__header_size(child_event); | |
6844c09d | 10464 | perf_event__id_header_size(child_event); |
614b6780 | 10465 | |
97dee4f3 PZ |
10466 | /* |
10467 | * Link it up in the child's context: | |
10468 | */ | |
cee010ec | 10469 | raw_spin_lock_irqsave(&child_ctx->lock, flags); |
97dee4f3 | 10470 | add_event_to_ctx(child_event, child_ctx); |
cee010ec | 10471 | raw_spin_unlock_irqrestore(&child_ctx->lock, flags); |
97dee4f3 | 10472 | |
97dee4f3 PZ |
10473 | /* |
10474 | * Link this into the parent event's child list | |
10475 | */ | |
97dee4f3 PZ |
10476 | list_add_tail(&child_event->child_list, &parent_event->child_list); |
10477 | mutex_unlock(&parent_event->child_mutex); | |
10478 | ||
10479 | return child_event; | |
10480 | } | |
10481 | ||
10482 | static int inherit_group(struct perf_event *parent_event, | |
10483 | struct task_struct *parent, | |
10484 | struct perf_event_context *parent_ctx, | |
10485 | struct task_struct *child, | |
10486 | struct perf_event_context *child_ctx) | |
10487 | { | |
10488 | struct perf_event *leader; | |
10489 | struct perf_event *sub; | |
10490 | struct perf_event *child_ctr; | |
10491 | ||
10492 | leader = inherit_event(parent_event, parent, parent_ctx, | |
10493 | child, NULL, child_ctx); | |
10494 | if (IS_ERR(leader)) | |
10495 | return PTR_ERR(leader); | |
10496 | list_for_each_entry(sub, &parent_event->sibling_list, group_entry) { | |
10497 | child_ctr = inherit_event(sub, parent, parent_ctx, | |
10498 | child, leader, child_ctx); | |
10499 | if (IS_ERR(child_ctr)) | |
10500 | return PTR_ERR(child_ctr); | |
10501 | } | |
10502 | return 0; | |
889ff015 FW |
10503 | } |
10504 | ||
10505 | static int | |
10506 | inherit_task_group(struct perf_event *event, struct task_struct *parent, | |
10507 | struct perf_event_context *parent_ctx, | |
8dc85d54 | 10508 | struct task_struct *child, int ctxn, |
889ff015 FW |
10509 | int *inherited_all) |
10510 | { | |
10511 | int ret; | |
8dc85d54 | 10512 | struct perf_event_context *child_ctx; |
889ff015 FW |
10513 | |
10514 | if (!event->attr.inherit) { | |
10515 | *inherited_all = 0; | |
10516 | return 0; | |
bbbee908 PZ |
10517 | } |
10518 | ||
fe4b04fa | 10519 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 FW |
10520 | if (!child_ctx) { |
10521 | /* | |
10522 | * This is executed from the parent task context, so | |
10523 | * inherit events that have been marked for cloning. | |
10524 | * First allocate and initialize a context for the | |
10525 | * child. | |
10526 | */ | |
bbbee908 | 10527 | |
734df5ab | 10528 | child_ctx = alloc_perf_context(parent_ctx->pmu, child); |
889ff015 FW |
10529 | if (!child_ctx) |
10530 | return -ENOMEM; | |
bbbee908 | 10531 | |
8dc85d54 | 10532 | child->perf_event_ctxp[ctxn] = child_ctx; |
889ff015 FW |
10533 | } |
10534 | ||
10535 | ret = inherit_group(event, parent, parent_ctx, | |
10536 | child, child_ctx); | |
10537 | ||
10538 | if (ret) | |
10539 | *inherited_all = 0; | |
10540 | ||
10541 | return ret; | |
bbbee908 PZ |
10542 | } |
10543 | ||
9b51f66d | 10544 | /* |
cdd6c482 | 10545 | * Initialize the perf_event context in task_struct |
9b51f66d | 10546 | */ |
985c8dcb | 10547 | static int perf_event_init_context(struct task_struct *child, int ctxn) |
9b51f66d | 10548 | { |
889ff015 | 10549 | struct perf_event_context *child_ctx, *parent_ctx; |
cdd6c482 IM |
10550 | struct perf_event_context *cloned_ctx; |
10551 | struct perf_event *event; | |
9b51f66d | 10552 | struct task_struct *parent = current; |
564c2b21 | 10553 | int inherited_all = 1; |
dddd3379 | 10554 | unsigned long flags; |
6ab423e0 | 10555 | int ret = 0; |
9b51f66d | 10556 | |
8dc85d54 | 10557 | if (likely(!parent->perf_event_ctxp[ctxn])) |
6ab423e0 PZ |
10558 | return 0; |
10559 | ||
ad3a37de | 10560 | /* |
25346b93 PM |
10561 | * If the parent's context is a clone, pin it so it won't get |
10562 | * swapped under us. | |
ad3a37de | 10563 | */ |
8dc85d54 | 10564 | parent_ctx = perf_pin_task_context(parent, ctxn); |
ffb4ef21 PZ |
10565 | if (!parent_ctx) |
10566 | return 0; | |
25346b93 | 10567 | |
ad3a37de PM |
10568 | /* |
10569 | * No need to check if parent_ctx != NULL here; since we saw | |
10570 | * it non-NULL earlier, the only reason for it to become NULL | |
10571 | * is if we exit, and since we're currently in the middle of | |
10572 | * a fork we can't be exiting at the same time. | |
10573 | */ | |
ad3a37de | 10574 | |
9b51f66d IM |
10575 | /* |
10576 | * Lock the parent list. No need to lock the child - not PID | |
10577 | * hashed yet and not running, so nobody can access it. | |
10578 | */ | |
d859e29f | 10579 | mutex_lock(&parent_ctx->mutex); |
9b51f66d IM |
10580 | |
10581 | /* | |
10582 | * We dont have to disable NMIs - we are only looking at | |
10583 | * the list, not manipulating it: | |
10584 | */ | |
889ff015 | 10585 | list_for_each_entry(event, &parent_ctx->pinned_groups, group_entry) { |
8dc85d54 PZ |
10586 | ret = inherit_task_group(event, parent, parent_ctx, |
10587 | child, ctxn, &inherited_all); | |
889ff015 FW |
10588 | if (ret) |
10589 | break; | |
10590 | } | |
b93f7978 | 10591 | |
dddd3379 TG |
10592 | /* |
10593 | * We can't hold ctx->lock when iterating the ->flexible_group list due | |
10594 | * to allocations, but we need to prevent rotation because | |
10595 | * rotate_ctx() will change the list from interrupt context. | |
10596 | */ | |
10597 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); | |
10598 | parent_ctx->rotate_disable = 1; | |
10599 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); | |
10600 | ||
889ff015 | 10601 | list_for_each_entry(event, &parent_ctx->flexible_groups, group_entry) { |
8dc85d54 PZ |
10602 | ret = inherit_task_group(event, parent, parent_ctx, |
10603 | child, ctxn, &inherited_all); | |
889ff015 | 10604 | if (ret) |
9b51f66d | 10605 | break; |
564c2b21 PM |
10606 | } |
10607 | ||
dddd3379 TG |
10608 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); |
10609 | parent_ctx->rotate_disable = 0; | |
dddd3379 | 10610 | |
8dc85d54 | 10611 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 | 10612 | |
05cbaa28 | 10613 | if (child_ctx && inherited_all) { |
564c2b21 PM |
10614 | /* |
10615 | * Mark the child context as a clone of the parent | |
10616 | * context, or of whatever the parent is a clone of. | |
c5ed5145 PZ |
10617 | * |
10618 | * Note that if the parent is a clone, the holding of | |
10619 | * parent_ctx->lock avoids it from being uncloned. | |
564c2b21 | 10620 | */ |
c5ed5145 | 10621 | cloned_ctx = parent_ctx->parent_ctx; |
ad3a37de PM |
10622 | if (cloned_ctx) { |
10623 | child_ctx->parent_ctx = cloned_ctx; | |
25346b93 | 10624 | child_ctx->parent_gen = parent_ctx->parent_gen; |
564c2b21 PM |
10625 | } else { |
10626 | child_ctx->parent_ctx = parent_ctx; | |
10627 | child_ctx->parent_gen = parent_ctx->generation; | |
10628 | } | |
10629 | get_ctx(child_ctx->parent_ctx); | |
9b51f66d IM |
10630 | } |
10631 | ||
c5ed5145 | 10632 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); |
d859e29f | 10633 | mutex_unlock(&parent_ctx->mutex); |
6ab423e0 | 10634 | |
25346b93 | 10635 | perf_unpin_context(parent_ctx); |
fe4b04fa | 10636 | put_ctx(parent_ctx); |
ad3a37de | 10637 | |
6ab423e0 | 10638 | return ret; |
9b51f66d IM |
10639 | } |
10640 | ||
8dc85d54 PZ |
10641 | /* |
10642 | * Initialize the perf_event context in task_struct | |
10643 | */ | |
10644 | int perf_event_init_task(struct task_struct *child) | |
10645 | { | |
10646 | int ctxn, ret; | |
10647 | ||
8550d7cb ON |
10648 | memset(child->perf_event_ctxp, 0, sizeof(child->perf_event_ctxp)); |
10649 | mutex_init(&child->perf_event_mutex); | |
10650 | INIT_LIST_HEAD(&child->perf_event_list); | |
10651 | ||
8dc85d54 PZ |
10652 | for_each_task_context_nr(ctxn) { |
10653 | ret = perf_event_init_context(child, ctxn); | |
6c72e350 PZ |
10654 | if (ret) { |
10655 | perf_event_free_task(child); | |
8dc85d54 | 10656 | return ret; |
6c72e350 | 10657 | } |
8dc85d54 PZ |
10658 | } |
10659 | ||
10660 | return 0; | |
10661 | } | |
10662 | ||
220b140b PM |
10663 | static void __init perf_event_init_all_cpus(void) |
10664 | { | |
b28ab83c | 10665 | struct swevent_htable *swhash; |
220b140b | 10666 | int cpu; |
220b140b PM |
10667 | |
10668 | for_each_possible_cpu(cpu) { | |
b28ab83c PZ |
10669 | swhash = &per_cpu(swevent_htable, cpu); |
10670 | mutex_init(&swhash->hlist_mutex); | |
2fde4f94 | 10671 | INIT_LIST_HEAD(&per_cpu(active_ctx_list, cpu)); |
f2fb6bef KL |
10672 | |
10673 | INIT_LIST_HEAD(&per_cpu(pmu_sb_events.list, cpu)); | |
10674 | raw_spin_lock_init(&per_cpu(pmu_sb_events.lock, cpu)); | |
e48c1788 | 10675 | |
058fe1c0 DCC |
10676 | #ifdef CONFIG_CGROUP_PERF |
10677 | INIT_LIST_HEAD(&per_cpu(cgrp_cpuctx_list, cpu)); | |
10678 | #endif | |
e48c1788 | 10679 | INIT_LIST_HEAD(&per_cpu(sched_cb_list, cpu)); |
220b140b PM |
10680 | } |
10681 | } | |
10682 | ||
00e16c3d | 10683 | int perf_event_init_cpu(unsigned int cpu) |
0793a61d | 10684 | { |
108b02cf | 10685 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
0793a61d | 10686 | |
b28ab83c | 10687 | mutex_lock(&swhash->hlist_mutex); |
059fcd8c | 10688 | if (swhash->hlist_refcount > 0 && !swevent_hlist_deref(swhash)) { |
76e1d904 FW |
10689 | struct swevent_hlist *hlist; |
10690 | ||
b28ab83c PZ |
10691 | hlist = kzalloc_node(sizeof(*hlist), GFP_KERNEL, cpu_to_node(cpu)); |
10692 | WARN_ON(!hlist); | |
10693 | rcu_assign_pointer(swhash->swevent_hlist, hlist); | |
76e1d904 | 10694 | } |
b28ab83c | 10695 | mutex_unlock(&swhash->hlist_mutex); |
00e16c3d | 10696 | return 0; |
0793a61d TG |
10697 | } |
10698 | ||
2965faa5 | 10699 | #if defined CONFIG_HOTPLUG_CPU || defined CONFIG_KEXEC_CORE |
108b02cf | 10700 | static void __perf_event_exit_context(void *__info) |
0793a61d | 10701 | { |
108b02cf | 10702 | struct perf_event_context *ctx = __info; |
fae3fde6 PZ |
10703 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
10704 | struct perf_event *event; | |
0793a61d | 10705 | |
fae3fde6 PZ |
10706 | raw_spin_lock(&ctx->lock); |
10707 | list_for_each_entry(event, &ctx->event_list, event_entry) | |
45a0e07a | 10708 | __perf_remove_from_context(event, cpuctx, ctx, (void *)DETACH_GROUP); |
fae3fde6 | 10709 | raw_spin_unlock(&ctx->lock); |
0793a61d | 10710 | } |
108b02cf PZ |
10711 | |
10712 | static void perf_event_exit_cpu_context(int cpu) | |
10713 | { | |
10714 | struct perf_event_context *ctx; | |
10715 | struct pmu *pmu; | |
10716 | int idx; | |
10717 | ||
10718 | idx = srcu_read_lock(&pmus_srcu); | |
10719 | list_for_each_entry_rcu(pmu, &pmus, entry) { | |
917bdd1c | 10720 | ctx = &per_cpu_ptr(pmu->pmu_cpu_context, cpu)->ctx; |
108b02cf PZ |
10721 | |
10722 | mutex_lock(&ctx->mutex); | |
10723 | smp_call_function_single(cpu, __perf_event_exit_context, ctx, 1); | |
10724 | mutex_unlock(&ctx->mutex); | |
10725 | } | |
10726 | srcu_read_unlock(&pmus_srcu, idx); | |
108b02cf | 10727 | } |
00e16c3d TG |
10728 | #else |
10729 | ||
10730 | static void perf_event_exit_cpu_context(int cpu) { } | |
10731 | ||
10732 | #endif | |
108b02cf | 10733 | |
00e16c3d | 10734 | int perf_event_exit_cpu(unsigned int cpu) |
0793a61d | 10735 | { |
e3703f8c | 10736 | perf_event_exit_cpu_context(cpu); |
00e16c3d | 10737 | return 0; |
0793a61d | 10738 | } |
0793a61d | 10739 | |
c277443c PZ |
10740 | static int |
10741 | perf_reboot(struct notifier_block *notifier, unsigned long val, void *v) | |
10742 | { | |
10743 | int cpu; | |
10744 | ||
10745 | for_each_online_cpu(cpu) | |
10746 | perf_event_exit_cpu(cpu); | |
10747 | ||
10748 | return NOTIFY_OK; | |
10749 | } | |
10750 | ||
10751 | /* | |
10752 | * Run the perf reboot notifier at the very last possible moment so that | |
10753 | * the generic watchdog code runs as long as possible. | |
10754 | */ | |
10755 | static struct notifier_block perf_reboot_notifier = { | |
10756 | .notifier_call = perf_reboot, | |
10757 | .priority = INT_MIN, | |
10758 | }; | |
10759 | ||
cdd6c482 | 10760 | void __init perf_event_init(void) |
0793a61d | 10761 | { |
3c502e7a JW |
10762 | int ret; |
10763 | ||
2e80a82a PZ |
10764 | idr_init(&pmu_idr); |
10765 | ||
220b140b | 10766 | perf_event_init_all_cpus(); |
b0a873eb | 10767 | init_srcu_struct(&pmus_srcu); |
2e80a82a PZ |
10768 | perf_pmu_register(&perf_swevent, "software", PERF_TYPE_SOFTWARE); |
10769 | perf_pmu_register(&perf_cpu_clock, NULL, -1); | |
10770 | perf_pmu_register(&perf_task_clock, NULL, -1); | |
b0a873eb | 10771 | perf_tp_register(); |
00e16c3d | 10772 | perf_event_init_cpu(smp_processor_id()); |
c277443c | 10773 | register_reboot_notifier(&perf_reboot_notifier); |
3c502e7a JW |
10774 | |
10775 | ret = init_hw_breakpoint(); | |
10776 | WARN(ret, "hw_breakpoint initialization failed with: %d", ret); | |
b2029520 | 10777 | |
b01c3a00 JO |
10778 | /* |
10779 | * Build time assertion that we keep the data_head at the intended | |
10780 | * location. IOW, validation we got the __reserved[] size right. | |
10781 | */ | |
10782 | BUILD_BUG_ON((offsetof(struct perf_event_mmap_page, data_head)) | |
10783 | != 1024); | |
0793a61d | 10784 | } |
abe43400 | 10785 | |
fd979c01 CS |
10786 | ssize_t perf_event_sysfs_show(struct device *dev, struct device_attribute *attr, |
10787 | char *page) | |
10788 | { | |
10789 | struct perf_pmu_events_attr *pmu_attr = | |
10790 | container_of(attr, struct perf_pmu_events_attr, attr); | |
10791 | ||
10792 | if (pmu_attr->event_str) | |
10793 | return sprintf(page, "%s\n", pmu_attr->event_str); | |
10794 | ||
10795 | return 0; | |
10796 | } | |
675965b0 | 10797 | EXPORT_SYMBOL_GPL(perf_event_sysfs_show); |
fd979c01 | 10798 | |
abe43400 PZ |
10799 | static int __init perf_event_sysfs_init(void) |
10800 | { | |
10801 | struct pmu *pmu; | |
10802 | int ret; | |
10803 | ||
10804 | mutex_lock(&pmus_lock); | |
10805 | ||
10806 | ret = bus_register(&pmu_bus); | |
10807 | if (ret) | |
10808 | goto unlock; | |
10809 | ||
10810 | list_for_each_entry(pmu, &pmus, entry) { | |
10811 | if (!pmu->name || pmu->type < 0) | |
10812 | continue; | |
10813 | ||
10814 | ret = pmu_dev_alloc(pmu); | |
10815 | WARN(ret, "Failed to register pmu: %s, reason %d\n", pmu->name, ret); | |
10816 | } | |
10817 | pmu_bus_running = 1; | |
10818 | ret = 0; | |
10819 | ||
10820 | unlock: | |
10821 | mutex_unlock(&pmus_lock); | |
10822 | ||
10823 | return ret; | |
10824 | } | |
10825 | device_initcall(perf_event_sysfs_init); | |
e5d1367f SE |
10826 | |
10827 | #ifdef CONFIG_CGROUP_PERF | |
eb95419b TH |
10828 | static struct cgroup_subsys_state * |
10829 | perf_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) | |
e5d1367f SE |
10830 | { |
10831 | struct perf_cgroup *jc; | |
e5d1367f | 10832 | |
1b15d055 | 10833 | jc = kzalloc(sizeof(*jc), GFP_KERNEL); |
e5d1367f SE |
10834 | if (!jc) |
10835 | return ERR_PTR(-ENOMEM); | |
10836 | ||
e5d1367f SE |
10837 | jc->info = alloc_percpu(struct perf_cgroup_info); |
10838 | if (!jc->info) { | |
10839 | kfree(jc); | |
10840 | return ERR_PTR(-ENOMEM); | |
10841 | } | |
10842 | ||
e5d1367f SE |
10843 | return &jc->css; |
10844 | } | |
10845 | ||
eb95419b | 10846 | static void perf_cgroup_css_free(struct cgroup_subsys_state *css) |
e5d1367f | 10847 | { |
eb95419b TH |
10848 | struct perf_cgroup *jc = container_of(css, struct perf_cgroup, css); |
10849 | ||
e5d1367f SE |
10850 | free_percpu(jc->info); |
10851 | kfree(jc); | |
10852 | } | |
10853 | ||
10854 | static int __perf_cgroup_move(void *info) | |
10855 | { | |
10856 | struct task_struct *task = info; | |
ddaaf4e2 | 10857 | rcu_read_lock(); |
e5d1367f | 10858 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT | PERF_CGROUP_SWIN); |
ddaaf4e2 | 10859 | rcu_read_unlock(); |
e5d1367f SE |
10860 | return 0; |
10861 | } | |
10862 | ||
1f7dd3e5 | 10863 | static void perf_cgroup_attach(struct cgroup_taskset *tset) |
e5d1367f | 10864 | { |
bb9d97b6 | 10865 | struct task_struct *task; |
1f7dd3e5 | 10866 | struct cgroup_subsys_state *css; |
bb9d97b6 | 10867 | |
1f7dd3e5 | 10868 | cgroup_taskset_for_each(task, css, tset) |
bb9d97b6 | 10869 | task_function_call(task, __perf_cgroup_move, task); |
e5d1367f SE |
10870 | } |
10871 | ||
073219e9 | 10872 | struct cgroup_subsys perf_event_cgrp_subsys = { |
92fb9748 TH |
10873 | .css_alloc = perf_cgroup_css_alloc, |
10874 | .css_free = perf_cgroup_css_free, | |
bb9d97b6 | 10875 | .attach = perf_cgroup_attach, |
e5d1367f SE |
10876 | }; |
10877 | #endif /* CONFIG_CGROUP_PERF */ |