Commit | Line | Data |
---|---|---|
0793a61d | 1 | /* |
57c0c15b | 2 | * Performance events core code: |
0793a61d | 3 | * |
98144511 | 4 | * Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de> |
e7e7ee2e | 5 | * Copyright (C) 2008-2011 Red Hat, Inc., Ingo Molnar |
90eec103 | 6 | * Copyright (C) 2008-2011 Red Hat, Inc., Peter Zijlstra |
d36b6910 | 7 | * Copyright © 2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com> |
7b732a75 | 8 | * |
57c0c15b | 9 | * For licensing details see kernel-base/COPYING |
0793a61d TG |
10 | */ |
11 | ||
12 | #include <linux/fs.h> | |
b9cacc7b | 13 | #include <linux/mm.h> |
0793a61d TG |
14 | #include <linux/cpu.h> |
15 | #include <linux/smp.h> | |
2e80a82a | 16 | #include <linux/idr.h> |
04289bb9 | 17 | #include <linux/file.h> |
0793a61d | 18 | #include <linux/poll.h> |
5a0e3ad6 | 19 | #include <linux/slab.h> |
76e1d904 | 20 | #include <linux/hash.h> |
12351ef8 | 21 | #include <linux/tick.h> |
0793a61d | 22 | #include <linux/sysfs.h> |
22a4f650 | 23 | #include <linux/dcache.h> |
0793a61d | 24 | #include <linux/percpu.h> |
22a4f650 | 25 | #include <linux/ptrace.h> |
c277443c | 26 | #include <linux/reboot.h> |
b9cacc7b | 27 | #include <linux/vmstat.h> |
abe43400 | 28 | #include <linux/device.h> |
6e5fdeed | 29 | #include <linux/export.h> |
906010b2 | 30 | #include <linux/vmalloc.h> |
b9cacc7b PZ |
31 | #include <linux/hardirq.h> |
32 | #include <linux/rculist.h> | |
0793a61d TG |
33 | #include <linux/uaccess.h> |
34 | #include <linux/syscalls.h> | |
35 | #include <linux/anon_inodes.h> | |
aa9c4c0f | 36 | #include <linux/kernel_stat.h> |
39bed6cb | 37 | #include <linux/cgroup.h> |
cdd6c482 | 38 | #include <linux/perf_event.h> |
af658dca | 39 | #include <linux/trace_events.h> |
3c502e7a | 40 | #include <linux/hw_breakpoint.h> |
c5ebcedb | 41 | #include <linux/mm_types.h> |
c464c76e | 42 | #include <linux/module.h> |
f972eb63 | 43 | #include <linux/mman.h> |
b3f20785 | 44 | #include <linux/compat.h> |
2541517c AS |
45 | #include <linux/bpf.h> |
46 | #include <linux/filter.h> | |
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 | ||
245 | static void event_function_local(struct perf_event *event, event_f func, void *data) | |
246 | { | |
247 | struct event_function_struct efs = { | |
248 | .event = event, | |
249 | .func = func, | |
250 | .data = data, | |
251 | }; | |
252 | ||
253 | int ret = event_function(&efs); | |
254 | WARN_ON_ONCE(ret); | |
255 | } | |
256 | ||
257 | static void event_function_call(struct perf_event *event, event_f func, void *data) | |
0017960f PZ |
258 | { |
259 | struct perf_event_context *ctx = event->ctx; | |
63b6da39 | 260 | struct task_struct *task = READ_ONCE(ctx->task); /* verified in event_function */ |
fae3fde6 PZ |
261 | struct event_function_struct efs = { |
262 | .event = event, | |
263 | .func = func, | |
264 | .data = data, | |
265 | }; | |
0017960f | 266 | |
c97f4736 PZ |
267 | if (!event->parent) { |
268 | /* | |
269 | * If this is a !child event, we must hold ctx::mutex to | |
270 | * stabilize the the event->ctx relation. See | |
271 | * perf_event_ctx_lock(). | |
272 | */ | |
273 | lockdep_assert_held(&ctx->mutex); | |
274 | } | |
0017960f PZ |
275 | |
276 | if (!task) { | |
fae3fde6 | 277 | cpu_function_call(event->cpu, event_function, &efs); |
0017960f PZ |
278 | return; |
279 | } | |
280 | ||
63b6da39 PZ |
281 | if (task == TASK_TOMBSTONE) |
282 | return; | |
283 | ||
a096309b | 284 | again: |
fae3fde6 | 285 | if (!task_function_call(task, event_function, &efs)) |
0017960f PZ |
286 | return; |
287 | ||
288 | raw_spin_lock_irq(&ctx->lock); | |
63b6da39 PZ |
289 | /* |
290 | * Reload the task pointer, it might have been changed by | |
291 | * a concurrent perf_event_context_sched_out(). | |
292 | */ | |
293 | task = ctx->task; | |
a096309b PZ |
294 | if (task == TASK_TOMBSTONE) { |
295 | raw_spin_unlock_irq(&ctx->lock); | |
296 | return; | |
0017960f | 297 | } |
a096309b PZ |
298 | if (ctx->is_active) { |
299 | raw_spin_unlock_irq(&ctx->lock); | |
300 | goto again; | |
301 | } | |
302 | func(event, NULL, ctx, data); | |
0017960f PZ |
303 | raw_spin_unlock_irq(&ctx->lock); |
304 | } | |
305 | ||
e5d1367f SE |
306 | #define PERF_FLAG_ALL (PERF_FLAG_FD_NO_GROUP |\ |
307 | PERF_FLAG_FD_OUTPUT |\ | |
a21b0b35 YD |
308 | PERF_FLAG_PID_CGROUP |\ |
309 | PERF_FLAG_FD_CLOEXEC) | |
e5d1367f | 310 | |
bce38cd5 SE |
311 | /* |
312 | * branch priv levels that need permission checks | |
313 | */ | |
314 | #define PERF_SAMPLE_BRANCH_PERM_PLM \ | |
315 | (PERF_SAMPLE_BRANCH_KERNEL |\ | |
316 | PERF_SAMPLE_BRANCH_HV) | |
317 | ||
0b3fcf17 SE |
318 | enum event_type_t { |
319 | EVENT_FLEXIBLE = 0x1, | |
320 | EVENT_PINNED = 0x2, | |
3cbaa590 | 321 | EVENT_TIME = 0x4, |
0b3fcf17 SE |
322 | EVENT_ALL = EVENT_FLEXIBLE | EVENT_PINNED, |
323 | }; | |
324 | ||
e5d1367f SE |
325 | /* |
326 | * perf_sched_events : >0 events exist | |
327 | * perf_cgroup_events: >0 per-cpu cgroup events exist on this cpu | |
328 | */ | |
9107c89e PZ |
329 | |
330 | static void perf_sched_delayed(struct work_struct *work); | |
331 | DEFINE_STATIC_KEY_FALSE(perf_sched_events); | |
332 | static DECLARE_DELAYED_WORK(perf_sched_work, perf_sched_delayed); | |
333 | static DEFINE_MUTEX(perf_sched_mutex); | |
334 | static atomic_t perf_sched_count; | |
335 | ||
e5d1367f | 336 | static DEFINE_PER_CPU(atomic_t, perf_cgroup_events); |
ba532500 | 337 | static DEFINE_PER_CPU(int, perf_sched_cb_usages); |
f2fb6bef | 338 | static DEFINE_PER_CPU(struct pmu_event_list, pmu_sb_events); |
e5d1367f | 339 | |
cdd6c482 IM |
340 | static atomic_t nr_mmap_events __read_mostly; |
341 | static atomic_t nr_comm_events __read_mostly; | |
342 | static atomic_t nr_task_events __read_mostly; | |
948b26b6 | 343 | static atomic_t nr_freq_events __read_mostly; |
45ac1403 | 344 | static atomic_t nr_switch_events __read_mostly; |
9ee318a7 | 345 | |
108b02cf PZ |
346 | static LIST_HEAD(pmus); |
347 | static DEFINE_MUTEX(pmus_lock); | |
348 | static struct srcu_struct pmus_srcu; | |
349 | ||
0764771d | 350 | /* |
cdd6c482 | 351 | * perf event paranoia level: |
0fbdea19 IM |
352 | * -1 - not paranoid at all |
353 | * 0 - disallow raw tracepoint access for unpriv | |
cdd6c482 | 354 | * 1 - disallow cpu events for unpriv |
0fbdea19 | 355 | * 2 - disallow kernel profiling for unpriv |
0764771d | 356 | */ |
0161028b | 357 | int sysctl_perf_event_paranoid __read_mostly = 2; |
0764771d | 358 | |
20443384 FW |
359 | /* Minimum for 512 kiB + 1 user control page */ |
360 | int sysctl_perf_event_mlock __read_mostly = 512 + (PAGE_SIZE / 1024); /* 'free' kiB per user */ | |
df58ab24 PZ |
361 | |
362 | /* | |
cdd6c482 | 363 | * max perf event sample rate |
df58ab24 | 364 | */ |
14c63f17 DH |
365 | #define DEFAULT_MAX_SAMPLE_RATE 100000 |
366 | #define DEFAULT_SAMPLE_PERIOD_NS (NSEC_PER_SEC / DEFAULT_MAX_SAMPLE_RATE) | |
367 | #define DEFAULT_CPU_TIME_MAX_PERCENT 25 | |
368 | ||
369 | int sysctl_perf_event_sample_rate __read_mostly = DEFAULT_MAX_SAMPLE_RATE; | |
370 | ||
371 | static int max_samples_per_tick __read_mostly = DIV_ROUND_UP(DEFAULT_MAX_SAMPLE_RATE, HZ); | |
372 | static int perf_sample_period_ns __read_mostly = DEFAULT_SAMPLE_PERIOD_NS; | |
373 | ||
d9494cb4 PZ |
374 | static int perf_sample_allowed_ns __read_mostly = |
375 | DEFAULT_SAMPLE_PERIOD_NS * DEFAULT_CPU_TIME_MAX_PERCENT / 100; | |
14c63f17 | 376 | |
18ab2cd3 | 377 | static void update_perf_cpu_limits(void) |
14c63f17 DH |
378 | { |
379 | u64 tmp = perf_sample_period_ns; | |
380 | ||
381 | tmp *= sysctl_perf_cpu_time_max_percent; | |
91a612ee PZ |
382 | tmp = div_u64(tmp, 100); |
383 | if (!tmp) | |
384 | tmp = 1; | |
385 | ||
386 | WRITE_ONCE(perf_sample_allowed_ns, tmp); | |
14c63f17 | 387 | } |
163ec435 | 388 | |
9e630205 SE |
389 | static int perf_rotate_context(struct perf_cpu_context *cpuctx); |
390 | ||
163ec435 PZ |
391 | int perf_proc_update_handler(struct ctl_table *table, int write, |
392 | void __user *buffer, size_t *lenp, | |
393 | loff_t *ppos) | |
394 | { | |
723478c8 | 395 | int ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
163ec435 PZ |
396 | |
397 | if (ret || !write) | |
398 | return ret; | |
399 | ||
ab7fdefb KL |
400 | /* |
401 | * If throttling is disabled don't allow the write: | |
402 | */ | |
403 | if (sysctl_perf_cpu_time_max_percent == 100 || | |
404 | sysctl_perf_cpu_time_max_percent == 0) | |
405 | return -EINVAL; | |
406 | ||
163ec435 | 407 | max_samples_per_tick = DIV_ROUND_UP(sysctl_perf_event_sample_rate, HZ); |
14c63f17 DH |
408 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; |
409 | update_perf_cpu_limits(); | |
410 | ||
411 | return 0; | |
412 | } | |
413 | ||
414 | int sysctl_perf_cpu_time_max_percent __read_mostly = DEFAULT_CPU_TIME_MAX_PERCENT; | |
415 | ||
416 | int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write, | |
417 | void __user *buffer, size_t *lenp, | |
418 | loff_t *ppos) | |
419 | { | |
420 | int ret = proc_dointvec(table, write, buffer, lenp, ppos); | |
421 | ||
422 | if (ret || !write) | |
423 | return ret; | |
424 | ||
b303e7c1 PZ |
425 | if (sysctl_perf_cpu_time_max_percent == 100 || |
426 | sysctl_perf_cpu_time_max_percent == 0) { | |
91a612ee PZ |
427 | printk(KERN_WARNING |
428 | "perf: Dynamic interrupt throttling disabled, can hang your system!\n"); | |
429 | WRITE_ONCE(perf_sample_allowed_ns, 0); | |
430 | } else { | |
431 | update_perf_cpu_limits(); | |
432 | } | |
163ec435 PZ |
433 | |
434 | return 0; | |
435 | } | |
1ccd1549 | 436 | |
14c63f17 DH |
437 | /* |
438 | * perf samples are done in some very critical code paths (NMIs). | |
439 | * If they take too much CPU time, the system can lock up and not | |
440 | * get any real work done. This will drop the sample rate when | |
441 | * we detect that events are taking too long. | |
442 | */ | |
443 | #define NR_ACCUMULATED_SAMPLES 128 | |
d9494cb4 | 444 | static DEFINE_PER_CPU(u64, running_sample_length); |
14c63f17 | 445 | |
91a612ee PZ |
446 | static u64 __report_avg; |
447 | static u64 __report_allowed; | |
448 | ||
6a02ad66 | 449 | static void perf_duration_warn(struct irq_work *w) |
14c63f17 | 450 | { |
0d87d7ec | 451 | printk_ratelimited(KERN_INFO |
91a612ee PZ |
452 | "perf: interrupt took too long (%lld > %lld), lowering " |
453 | "kernel.perf_event_max_sample_rate to %d\n", | |
454 | __report_avg, __report_allowed, | |
455 | sysctl_perf_event_sample_rate); | |
6a02ad66 PZ |
456 | } |
457 | ||
458 | static DEFINE_IRQ_WORK(perf_duration_work, perf_duration_warn); | |
459 | ||
460 | void perf_sample_event_took(u64 sample_len_ns) | |
461 | { | |
91a612ee PZ |
462 | u64 max_len = READ_ONCE(perf_sample_allowed_ns); |
463 | u64 running_len; | |
464 | u64 avg_len; | |
465 | u32 max; | |
14c63f17 | 466 | |
91a612ee | 467 | if (max_len == 0) |
14c63f17 DH |
468 | return; |
469 | ||
91a612ee PZ |
470 | /* Decay the counter by 1 average sample. */ |
471 | running_len = __this_cpu_read(running_sample_length); | |
472 | running_len -= running_len/NR_ACCUMULATED_SAMPLES; | |
473 | running_len += sample_len_ns; | |
474 | __this_cpu_write(running_sample_length, running_len); | |
14c63f17 DH |
475 | |
476 | /* | |
91a612ee PZ |
477 | * Note: this will be biased artifically low until we have |
478 | * seen NR_ACCUMULATED_SAMPLES. Doing it this way keeps us | |
14c63f17 DH |
479 | * from having to maintain a count. |
480 | */ | |
91a612ee PZ |
481 | avg_len = running_len/NR_ACCUMULATED_SAMPLES; |
482 | if (avg_len <= max_len) | |
14c63f17 DH |
483 | return; |
484 | ||
91a612ee PZ |
485 | __report_avg = avg_len; |
486 | __report_allowed = max_len; | |
14c63f17 | 487 | |
91a612ee PZ |
488 | /* |
489 | * Compute a throttle threshold 25% below the current duration. | |
490 | */ | |
491 | avg_len += avg_len / 4; | |
492 | max = (TICK_NSEC / 100) * sysctl_perf_cpu_time_max_percent; | |
493 | if (avg_len < max) | |
494 | max /= (u32)avg_len; | |
495 | else | |
496 | max = 1; | |
14c63f17 | 497 | |
91a612ee PZ |
498 | WRITE_ONCE(perf_sample_allowed_ns, avg_len); |
499 | WRITE_ONCE(max_samples_per_tick, max); | |
500 | ||
501 | sysctl_perf_event_sample_rate = max * HZ; | |
502 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; | |
6a02ad66 | 503 | |
cd578abb | 504 | if (!irq_work_queue(&perf_duration_work)) { |
91a612ee | 505 | early_printk("perf: interrupt took too long (%lld > %lld), lowering " |
cd578abb | 506 | "kernel.perf_event_max_sample_rate to %d\n", |
91a612ee | 507 | __report_avg, __report_allowed, |
cd578abb PZ |
508 | sysctl_perf_event_sample_rate); |
509 | } | |
14c63f17 DH |
510 | } |
511 | ||
cdd6c482 | 512 | static atomic64_t perf_event_id; |
a96bbc16 | 513 | |
0b3fcf17 SE |
514 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, |
515 | enum event_type_t event_type); | |
516 | ||
517 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
518 | enum event_type_t event_type, |
519 | struct task_struct *task); | |
520 | ||
521 | static void update_context_time(struct perf_event_context *ctx); | |
522 | static u64 perf_event_time(struct perf_event *event); | |
0b3fcf17 | 523 | |
cdd6c482 | 524 | void __weak perf_event_print_debug(void) { } |
0793a61d | 525 | |
84c79910 | 526 | extern __weak const char *perf_pmu_name(void) |
0793a61d | 527 | { |
84c79910 | 528 | return "pmu"; |
0793a61d TG |
529 | } |
530 | ||
0b3fcf17 SE |
531 | static inline u64 perf_clock(void) |
532 | { | |
533 | return local_clock(); | |
534 | } | |
535 | ||
34f43927 PZ |
536 | static inline u64 perf_event_clock(struct perf_event *event) |
537 | { | |
538 | return event->clock(); | |
539 | } | |
540 | ||
e5d1367f SE |
541 | #ifdef CONFIG_CGROUP_PERF |
542 | ||
e5d1367f SE |
543 | static inline bool |
544 | perf_cgroup_match(struct perf_event *event) | |
545 | { | |
546 | struct perf_event_context *ctx = event->ctx; | |
547 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
548 | ||
ef824fa1 TH |
549 | /* @event doesn't care about cgroup */ |
550 | if (!event->cgrp) | |
551 | return true; | |
552 | ||
553 | /* wants specific cgroup scope but @cpuctx isn't associated with any */ | |
554 | if (!cpuctx->cgrp) | |
555 | return false; | |
556 | ||
557 | /* | |
558 | * Cgroup scoping is recursive. An event enabled for a cgroup is | |
559 | * also enabled for all its descendant cgroups. If @cpuctx's | |
560 | * cgroup is a descendant of @event's (the test covers identity | |
561 | * case), it's a match. | |
562 | */ | |
563 | return cgroup_is_descendant(cpuctx->cgrp->css.cgroup, | |
564 | event->cgrp->css.cgroup); | |
e5d1367f SE |
565 | } |
566 | ||
e5d1367f SE |
567 | static inline void perf_detach_cgroup(struct perf_event *event) |
568 | { | |
4e2ba650 | 569 | css_put(&event->cgrp->css); |
e5d1367f SE |
570 | event->cgrp = NULL; |
571 | } | |
572 | ||
573 | static inline int is_cgroup_event(struct perf_event *event) | |
574 | { | |
575 | return event->cgrp != NULL; | |
576 | } | |
577 | ||
578 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
579 | { | |
580 | struct perf_cgroup_info *t; | |
581 | ||
582 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
583 | return t->time; | |
584 | } | |
585 | ||
586 | static inline void __update_cgrp_time(struct perf_cgroup *cgrp) | |
587 | { | |
588 | struct perf_cgroup_info *info; | |
589 | u64 now; | |
590 | ||
591 | now = perf_clock(); | |
592 | ||
593 | info = this_cpu_ptr(cgrp->info); | |
594 | ||
595 | info->time += now - info->timestamp; | |
596 | info->timestamp = now; | |
597 | } | |
598 | ||
599 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
600 | { | |
601 | struct perf_cgroup *cgrp_out = cpuctx->cgrp; | |
602 | if (cgrp_out) | |
603 | __update_cgrp_time(cgrp_out); | |
604 | } | |
605 | ||
606 | static inline void update_cgrp_time_from_event(struct perf_event *event) | |
607 | { | |
3f7cce3c SE |
608 | struct perf_cgroup *cgrp; |
609 | ||
e5d1367f | 610 | /* |
3f7cce3c SE |
611 | * ensure we access cgroup data only when needed and |
612 | * when we know the cgroup is pinned (css_get) | |
e5d1367f | 613 | */ |
3f7cce3c | 614 | if (!is_cgroup_event(event)) |
e5d1367f SE |
615 | return; |
616 | ||
614e4c4e | 617 | cgrp = perf_cgroup_from_task(current, event->ctx); |
3f7cce3c SE |
618 | /* |
619 | * Do not update time when cgroup is not active | |
620 | */ | |
621 | if (cgrp == event->cgrp) | |
622 | __update_cgrp_time(event->cgrp); | |
e5d1367f SE |
623 | } |
624 | ||
625 | static inline void | |
3f7cce3c SE |
626 | perf_cgroup_set_timestamp(struct task_struct *task, |
627 | struct perf_event_context *ctx) | |
e5d1367f SE |
628 | { |
629 | struct perf_cgroup *cgrp; | |
630 | struct perf_cgroup_info *info; | |
631 | ||
3f7cce3c SE |
632 | /* |
633 | * ctx->lock held by caller | |
634 | * ensure we do not access cgroup data | |
635 | * unless we have the cgroup pinned (css_get) | |
636 | */ | |
637 | if (!task || !ctx->nr_cgroups) | |
e5d1367f SE |
638 | return; |
639 | ||
614e4c4e | 640 | cgrp = perf_cgroup_from_task(task, ctx); |
e5d1367f | 641 | info = this_cpu_ptr(cgrp->info); |
3f7cce3c | 642 | info->timestamp = ctx->timestamp; |
e5d1367f SE |
643 | } |
644 | ||
645 | #define PERF_CGROUP_SWOUT 0x1 /* cgroup switch out every event */ | |
646 | #define PERF_CGROUP_SWIN 0x2 /* cgroup switch in events based on task */ | |
647 | ||
648 | /* | |
649 | * reschedule events based on the cgroup constraint of task. | |
650 | * | |
651 | * mode SWOUT : schedule out everything | |
652 | * mode SWIN : schedule in based on cgroup for next | |
653 | */ | |
18ab2cd3 | 654 | static void perf_cgroup_switch(struct task_struct *task, int mode) |
e5d1367f SE |
655 | { |
656 | struct perf_cpu_context *cpuctx; | |
657 | struct pmu *pmu; | |
658 | unsigned long flags; | |
659 | ||
660 | /* | |
661 | * disable interrupts to avoid geting nr_cgroup | |
662 | * changes via __perf_event_disable(). Also | |
663 | * avoids preemption. | |
664 | */ | |
665 | local_irq_save(flags); | |
666 | ||
667 | /* | |
668 | * we reschedule only in the presence of cgroup | |
669 | * constrained events. | |
670 | */ | |
e5d1367f SE |
671 | |
672 | list_for_each_entry_rcu(pmu, &pmus, entry) { | |
e5d1367f | 673 | cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
95cf59ea PZ |
674 | if (cpuctx->unique_pmu != pmu) |
675 | continue; /* ensure we process each cpuctx once */ | |
e5d1367f | 676 | |
e5d1367f SE |
677 | /* |
678 | * perf_cgroup_events says at least one | |
679 | * context on this CPU has cgroup events. | |
680 | * | |
681 | * ctx->nr_cgroups reports the number of cgroup | |
682 | * events for a context. | |
683 | */ | |
684 | if (cpuctx->ctx.nr_cgroups > 0) { | |
facc4307 PZ |
685 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
686 | perf_pmu_disable(cpuctx->ctx.pmu); | |
e5d1367f SE |
687 | |
688 | if (mode & PERF_CGROUP_SWOUT) { | |
689 | cpu_ctx_sched_out(cpuctx, EVENT_ALL); | |
690 | /* | |
691 | * must not be done before ctxswout due | |
692 | * to event_filter_match() in event_sched_out() | |
693 | */ | |
694 | cpuctx->cgrp = NULL; | |
695 | } | |
696 | ||
697 | if (mode & PERF_CGROUP_SWIN) { | |
e566b76e | 698 | WARN_ON_ONCE(cpuctx->cgrp); |
95cf59ea PZ |
699 | /* |
700 | * set cgrp before ctxsw in to allow | |
701 | * event_filter_match() to not have to pass | |
702 | * task around | |
614e4c4e SE |
703 | * we pass the cpuctx->ctx to perf_cgroup_from_task() |
704 | * because cgorup events are only per-cpu | |
e5d1367f | 705 | */ |
614e4c4e | 706 | cpuctx->cgrp = perf_cgroup_from_task(task, &cpuctx->ctx); |
e5d1367f SE |
707 | cpu_ctx_sched_in(cpuctx, EVENT_ALL, task); |
708 | } | |
facc4307 PZ |
709 | perf_pmu_enable(cpuctx->ctx.pmu); |
710 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
e5d1367f | 711 | } |
e5d1367f SE |
712 | } |
713 | ||
e5d1367f SE |
714 | local_irq_restore(flags); |
715 | } | |
716 | ||
a8d757ef SE |
717 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
718 | struct task_struct *next) | |
e5d1367f | 719 | { |
a8d757ef SE |
720 | struct perf_cgroup *cgrp1; |
721 | struct perf_cgroup *cgrp2 = NULL; | |
722 | ||
ddaaf4e2 | 723 | rcu_read_lock(); |
a8d757ef SE |
724 | /* |
725 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
726 | * we do not need to pass the ctx here because we know |
727 | * we are holding the rcu lock | |
a8d757ef | 728 | */ |
614e4c4e | 729 | cgrp1 = perf_cgroup_from_task(task, NULL); |
70a01657 | 730 | cgrp2 = perf_cgroup_from_task(next, NULL); |
a8d757ef SE |
731 | |
732 | /* | |
733 | * only schedule out current cgroup events if we know | |
734 | * that we are switching to a different cgroup. Otherwise, | |
735 | * do no touch the cgroup events. | |
736 | */ | |
737 | if (cgrp1 != cgrp2) | |
738 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT); | |
ddaaf4e2 SE |
739 | |
740 | rcu_read_unlock(); | |
e5d1367f SE |
741 | } |
742 | ||
a8d757ef SE |
743 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
744 | struct task_struct *task) | |
e5d1367f | 745 | { |
a8d757ef SE |
746 | struct perf_cgroup *cgrp1; |
747 | struct perf_cgroup *cgrp2 = NULL; | |
748 | ||
ddaaf4e2 | 749 | rcu_read_lock(); |
a8d757ef SE |
750 | /* |
751 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
752 | * we do not need to pass the ctx here because we know |
753 | * we are holding the rcu lock | |
a8d757ef | 754 | */ |
614e4c4e | 755 | cgrp1 = perf_cgroup_from_task(task, NULL); |
614e4c4e | 756 | cgrp2 = perf_cgroup_from_task(prev, NULL); |
a8d757ef SE |
757 | |
758 | /* | |
759 | * only need to schedule in cgroup events if we are changing | |
760 | * cgroup during ctxsw. Cgroup events were not scheduled | |
761 | * out of ctxsw out if that was not the case. | |
762 | */ | |
763 | if (cgrp1 != cgrp2) | |
764 | perf_cgroup_switch(task, PERF_CGROUP_SWIN); | |
ddaaf4e2 SE |
765 | |
766 | rcu_read_unlock(); | |
e5d1367f SE |
767 | } |
768 | ||
769 | static inline int perf_cgroup_connect(int fd, struct perf_event *event, | |
770 | struct perf_event_attr *attr, | |
771 | struct perf_event *group_leader) | |
772 | { | |
773 | struct perf_cgroup *cgrp; | |
774 | struct cgroup_subsys_state *css; | |
2903ff01 AV |
775 | struct fd f = fdget(fd); |
776 | int ret = 0; | |
e5d1367f | 777 | |
2903ff01 | 778 | if (!f.file) |
e5d1367f SE |
779 | return -EBADF; |
780 | ||
b583043e | 781 | css = css_tryget_online_from_dir(f.file->f_path.dentry, |
ec903c0c | 782 | &perf_event_cgrp_subsys); |
3db272c0 LZ |
783 | if (IS_ERR(css)) { |
784 | ret = PTR_ERR(css); | |
785 | goto out; | |
786 | } | |
e5d1367f SE |
787 | |
788 | cgrp = container_of(css, struct perf_cgroup, css); | |
789 | event->cgrp = cgrp; | |
790 | ||
791 | /* | |
792 | * all events in a group must monitor | |
793 | * the same cgroup because a task belongs | |
794 | * to only one perf cgroup at a time | |
795 | */ | |
796 | if (group_leader && group_leader->cgrp != cgrp) { | |
797 | perf_detach_cgroup(event); | |
798 | ret = -EINVAL; | |
e5d1367f | 799 | } |
3db272c0 | 800 | out: |
2903ff01 | 801 | fdput(f); |
e5d1367f SE |
802 | return ret; |
803 | } | |
804 | ||
805 | static inline void | |
806 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
807 | { | |
808 | struct perf_cgroup_info *t; | |
809 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
810 | event->shadow_ctx_time = now - t->timestamp; | |
811 | } | |
812 | ||
813 | static inline void | |
814 | perf_cgroup_defer_enabled(struct perf_event *event) | |
815 | { | |
816 | /* | |
817 | * when the current task's perf cgroup does not match | |
818 | * the event's, we need to remember to call the | |
819 | * perf_mark_enable() function the first time a task with | |
820 | * a matching perf cgroup is scheduled in. | |
821 | */ | |
822 | if (is_cgroup_event(event) && !perf_cgroup_match(event)) | |
823 | event->cgrp_defer_enabled = 1; | |
824 | } | |
825 | ||
826 | static inline void | |
827 | perf_cgroup_mark_enabled(struct perf_event *event, | |
828 | struct perf_event_context *ctx) | |
829 | { | |
830 | struct perf_event *sub; | |
831 | u64 tstamp = perf_event_time(event); | |
832 | ||
833 | if (!event->cgrp_defer_enabled) | |
834 | return; | |
835 | ||
836 | event->cgrp_defer_enabled = 0; | |
837 | ||
838 | event->tstamp_enabled = tstamp - event->total_time_enabled; | |
839 | list_for_each_entry(sub, &event->sibling_list, group_entry) { | |
840 | if (sub->state >= PERF_EVENT_STATE_INACTIVE) { | |
841 | sub->tstamp_enabled = tstamp - sub->total_time_enabled; | |
842 | sub->cgrp_defer_enabled = 0; | |
843 | } | |
844 | } | |
845 | } | |
846 | #else /* !CONFIG_CGROUP_PERF */ | |
847 | ||
848 | static inline bool | |
849 | perf_cgroup_match(struct perf_event *event) | |
850 | { | |
851 | return true; | |
852 | } | |
853 | ||
854 | static inline void perf_detach_cgroup(struct perf_event *event) | |
855 | {} | |
856 | ||
857 | static inline int is_cgroup_event(struct perf_event *event) | |
858 | { | |
859 | return 0; | |
860 | } | |
861 | ||
862 | static inline u64 perf_cgroup_event_cgrp_time(struct perf_event *event) | |
863 | { | |
864 | return 0; | |
865 | } | |
866 | ||
867 | static inline void update_cgrp_time_from_event(struct perf_event *event) | |
868 | { | |
869 | } | |
870 | ||
871 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
872 | { | |
873 | } | |
874 | ||
a8d757ef SE |
875 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
876 | struct task_struct *next) | |
e5d1367f SE |
877 | { |
878 | } | |
879 | ||
a8d757ef SE |
880 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
881 | struct task_struct *task) | |
e5d1367f SE |
882 | { |
883 | } | |
884 | ||
885 | static inline int perf_cgroup_connect(pid_t pid, struct perf_event *event, | |
886 | struct perf_event_attr *attr, | |
887 | struct perf_event *group_leader) | |
888 | { | |
889 | return -EINVAL; | |
890 | } | |
891 | ||
892 | static inline void | |
3f7cce3c SE |
893 | perf_cgroup_set_timestamp(struct task_struct *task, |
894 | struct perf_event_context *ctx) | |
e5d1367f SE |
895 | { |
896 | } | |
897 | ||
898 | void | |
899 | perf_cgroup_switch(struct task_struct *task, struct task_struct *next) | |
900 | { | |
901 | } | |
902 | ||
903 | static inline void | |
904 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
905 | { | |
906 | } | |
907 | ||
908 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
909 | { | |
910 | return 0; | |
911 | } | |
912 | ||
913 | static inline void | |
914 | perf_cgroup_defer_enabled(struct perf_event *event) | |
915 | { | |
916 | } | |
917 | ||
918 | static inline void | |
919 | perf_cgroup_mark_enabled(struct perf_event *event, | |
920 | struct perf_event_context *ctx) | |
921 | { | |
922 | } | |
923 | #endif | |
924 | ||
9e630205 SE |
925 | /* |
926 | * set default to be dependent on timer tick just | |
927 | * like original code | |
928 | */ | |
929 | #define PERF_CPU_HRTIMER (1000 / HZ) | |
930 | /* | |
931 | * function must be called with interrupts disbled | |
932 | */ | |
272325c4 | 933 | static enum hrtimer_restart perf_mux_hrtimer_handler(struct hrtimer *hr) |
9e630205 SE |
934 | { |
935 | struct perf_cpu_context *cpuctx; | |
9e630205 SE |
936 | int rotations = 0; |
937 | ||
938 | WARN_ON(!irqs_disabled()); | |
939 | ||
940 | cpuctx = container_of(hr, struct perf_cpu_context, hrtimer); | |
9e630205 SE |
941 | rotations = perf_rotate_context(cpuctx); |
942 | ||
4cfafd30 PZ |
943 | raw_spin_lock(&cpuctx->hrtimer_lock); |
944 | if (rotations) | |
9e630205 | 945 | hrtimer_forward_now(hr, cpuctx->hrtimer_interval); |
4cfafd30 PZ |
946 | else |
947 | cpuctx->hrtimer_active = 0; | |
948 | raw_spin_unlock(&cpuctx->hrtimer_lock); | |
9e630205 | 949 | |
4cfafd30 | 950 | return rotations ? HRTIMER_RESTART : HRTIMER_NORESTART; |
9e630205 SE |
951 | } |
952 | ||
272325c4 | 953 | static void __perf_mux_hrtimer_init(struct perf_cpu_context *cpuctx, int cpu) |
9e630205 | 954 | { |
272325c4 | 955 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 956 | struct pmu *pmu = cpuctx->ctx.pmu; |
272325c4 | 957 | u64 interval; |
9e630205 SE |
958 | |
959 | /* no multiplexing needed for SW PMU */ | |
960 | if (pmu->task_ctx_nr == perf_sw_context) | |
961 | return; | |
962 | ||
62b85639 SE |
963 | /* |
964 | * check default is sane, if not set then force to | |
965 | * default interval (1/tick) | |
966 | */ | |
272325c4 PZ |
967 | interval = pmu->hrtimer_interval_ms; |
968 | if (interval < 1) | |
969 | interval = pmu->hrtimer_interval_ms = PERF_CPU_HRTIMER; | |
62b85639 | 970 | |
272325c4 | 971 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * interval); |
9e630205 | 972 | |
4cfafd30 PZ |
973 | raw_spin_lock_init(&cpuctx->hrtimer_lock); |
974 | hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_PINNED); | |
272325c4 | 975 | timer->function = perf_mux_hrtimer_handler; |
9e630205 SE |
976 | } |
977 | ||
272325c4 | 978 | static int perf_mux_hrtimer_restart(struct perf_cpu_context *cpuctx) |
9e630205 | 979 | { |
272325c4 | 980 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 981 | struct pmu *pmu = cpuctx->ctx.pmu; |
4cfafd30 | 982 | unsigned long flags; |
9e630205 SE |
983 | |
984 | /* not for SW PMU */ | |
985 | if (pmu->task_ctx_nr == perf_sw_context) | |
272325c4 | 986 | return 0; |
9e630205 | 987 | |
4cfafd30 PZ |
988 | raw_spin_lock_irqsave(&cpuctx->hrtimer_lock, flags); |
989 | if (!cpuctx->hrtimer_active) { | |
990 | cpuctx->hrtimer_active = 1; | |
991 | hrtimer_forward_now(timer, cpuctx->hrtimer_interval); | |
992 | hrtimer_start_expires(timer, HRTIMER_MODE_ABS_PINNED); | |
993 | } | |
994 | raw_spin_unlock_irqrestore(&cpuctx->hrtimer_lock, flags); | |
9e630205 | 995 | |
272325c4 | 996 | return 0; |
9e630205 SE |
997 | } |
998 | ||
33696fc0 | 999 | void perf_pmu_disable(struct pmu *pmu) |
9e35ad38 | 1000 | { |
33696fc0 PZ |
1001 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1002 | if (!(*count)++) | |
1003 | pmu->pmu_disable(pmu); | |
9e35ad38 | 1004 | } |
9e35ad38 | 1005 | |
33696fc0 | 1006 | void perf_pmu_enable(struct pmu *pmu) |
9e35ad38 | 1007 | { |
33696fc0 PZ |
1008 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1009 | if (!--(*count)) | |
1010 | pmu->pmu_enable(pmu); | |
9e35ad38 | 1011 | } |
9e35ad38 | 1012 | |
2fde4f94 | 1013 | static DEFINE_PER_CPU(struct list_head, active_ctx_list); |
e9d2b064 PZ |
1014 | |
1015 | /* | |
2fde4f94 MR |
1016 | * perf_event_ctx_activate(), perf_event_ctx_deactivate(), and |
1017 | * perf_event_task_tick() are fully serialized because they're strictly cpu | |
1018 | * affine and perf_event_ctx{activate,deactivate} are called with IRQs | |
1019 | * disabled, while perf_event_task_tick is called from IRQ context. | |
e9d2b064 | 1020 | */ |
2fde4f94 | 1021 | static void perf_event_ctx_activate(struct perf_event_context *ctx) |
9e35ad38 | 1022 | { |
2fde4f94 | 1023 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
b5ab4cd5 | 1024 | |
e9d2b064 | 1025 | WARN_ON(!irqs_disabled()); |
b5ab4cd5 | 1026 | |
2fde4f94 MR |
1027 | WARN_ON(!list_empty(&ctx->active_ctx_list)); |
1028 | ||
1029 | list_add(&ctx->active_ctx_list, head); | |
1030 | } | |
1031 | ||
1032 | static void perf_event_ctx_deactivate(struct perf_event_context *ctx) | |
1033 | { | |
1034 | WARN_ON(!irqs_disabled()); | |
1035 | ||
1036 | WARN_ON(list_empty(&ctx->active_ctx_list)); | |
1037 | ||
1038 | list_del_init(&ctx->active_ctx_list); | |
9e35ad38 | 1039 | } |
9e35ad38 | 1040 | |
cdd6c482 | 1041 | static void get_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1042 | { |
e5289d4a | 1043 | WARN_ON(!atomic_inc_not_zero(&ctx->refcount)); |
a63eaf34 PM |
1044 | } |
1045 | ||
4af57ef2 YZ |
1046 | static void free_ctx(struct rcu_head *head) |
1047 | { | |
1048 | struct perf_event_context *ctx; | |
1049 | ||
1050 | ctx = container_of(head, struct perf_event_context, rcu_head); | |
1051 | kfree(ctx->task_ctx_data); | |
1052 | kfree(ctx); | |
1053 | } | |
1054 | ||
cdd6c482 | 1055 | static void put_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1056 | { |
564c2b21 PM |
1057 | if (atomic_dec_and_test(&ctx->refcount)) { |
1058 | if (ctx->parent_ctx) | |
1059 | put_ctx(ctx->parent_ctx); | |
63b6da39 | 1060 | if (ctx->task && ctx->task != TASK_TOMBSTONE) |
c93f7669 | 1061 | put_task_struct(ctx->task); |
4af57ef2 | 1062 | call_rcu(&ctx->rcu_head, free_ctx); |
564c2b21 | 1063 | } |
a63eaf34 PM |
1064 | } |
1065 | ||
f63a8daa PZ |
1066 | /* |
1067 | * Because of perf_event::ctx migration in sys_perf_event_open::move_group and | |
1068 | * perf_pmu_migrate_context() we need some magic. | |
1069 | * | |
1070 | * Those places that change perf_event::ctx will hold both | |
1071 | * perf_event_ctx::mutex of the 'old' and 'new' ctx value. | |
1072 | * | |
8b10c5e2 PZ |
1073 | * Lock ordering is by mutex address. There are two other sites where |
1074 | * perf_event_context::mutex nests and those are: | |
1075 | * | |
1076 | * - perf_event_exit_task_context() [ child , 0 ] | |
8ba289b8 PZ |
1077 | * perf_event_exit_event() |
1078 | * put_event() [ parent, 1 ] | |
8b10c5e2 PZ |
1079 | * |
1080 | * - perf_event_init_context() [ parent, 0 ] | |
1081 | * inherit_task_group() | |
1082 | * inherit_group() | |
1083 | * inherit_event() | |
1084 | * perf_event_alloc() | |
1085 | * perf_init_event() | |
1086 | * perf_try_init_event() [ child , 1 ] | |
1087 | * | |
1088 | * While it appears there is an obvious deadlock here -- the parent and child | |
1089 | * nesting levels are inverted between the two. This is in fact safe because | |
1090 | * life-time rules separate them. That is an exiting task cannot fork, and a | |
1091 | * spawning task cannot (yet) exit. | |
1092 | * | |
1093 | * But remember that that these are parent<->child context relations, and | |
1094 | * migration does not affect children, therefore these two orderings should not | |
1095 | * interact. | |
f63a8daa PZ |
1096 | * |
1097 | * The change in perf_event::ctx does not affect children (as claimed above) | |
1098 | * because the sys_perf_event_open() case will install a new event and break | |
1099 | * the ctx parent<->child relation, and perf_pmu_migrate_context() is only | |
1100 | * concerned with cpuctx and that doesn't have children. | |
1101 | * | |
1102 | * The places that change perf_event::ctx will issue: | |
1103 | * | |
1104 | * perf_remove_from_context(); | |
1105 | * synchronize_rcu(); | |
1106 | * perf_install_in_context(); | |
1107 | * | |
1108 | * to affect the change. The remove_from_context() + synchronize_rcu() should | |
1109 | * quiesce the event, after which we can install it in the new location. This | |
1110 | * means that only external vectors (perf_fops, prctl) can perturb the event | |
1111 | * while in transit. Therefore all such accessors should also acquire | |
1112 | * perf_event_context::mutex to serialize against this. | |
1113 | * | |
1114 | * However; because event->ctx can change while we're waiting to acquire | |
1115 | * ctx->mutex we must be careful and use the below perf_event_ctx_lock() | |
1116 | * function. | |
1117 | * | |
1118 | * Lock order: | |
79c9ce57 | 1119 | * cred_guard_mutex |
f63a8daa PZ |
1120 | * task_struct::perf_event_mutex |
1121 | * perf_event_context::mutex | |
f63a8daa | 1122 | * perf_event::child_mutex; |
07c4a776 | 1123 | * perf_event_context::lock |
f63a8daa PZ |
1124 | * perf_event::mmap_mutex |
1125 | * mmap_sem | |
1126 | */ | |
a83fe28e PZ |
1127 | static struct perf_event_context * |
1128 | perf_event_ctx_lock_nested(struct perf_event *event, int nesting) | |
f63a8daa PZ |
1129 | { |
1130 | struct perf_event_context *ctx; | |
1131 | ||
1132 | again: | |
1133 | rcu_read_lock(); | |
1134 | ctx = ACCESS_ONCE(event->ctx); | |
1135 | if (!atomic_inc_not_zero(&ctx->refcount)) { | |
1136 | rcu_read_unlock(); | |
1137 | goto again; | |
1138 | } | |
1139 | rcu_read_unlock(); | |
1140 | ||
a83fe28e | 1141 | mutex_lock_nested(&ctx->mutex, nesting); |
f63a8daa PZ |
1142 | if (event->ctx != ctx) { |
1143 | mutex_unlock(&ctx->mutex); | |
1144 | put_ctx(ctx); | |
1145 | goto again; | |
1146 | } | |
1147 | ||
1148 | return ctx; | |
1149 | } | |
1150 | ||
a83fe28e PZ |
1151 | static inline struct perf_event_context * |
1152 | perf_event_ctx_lock(struct perf_event *event) | |
1153 | { | |
1154 | return perf_event_ctx_lock_nested(event, 0); | |
1155 | } | |
1156 | ||
f63a8daa PZ |
1157 | static void perf_event_ctx_unlock(struct perf_event *event, |
1158 | struct perf_event_context *ctx) | |
1159 | { | |
1160 | mutex_unlock(&ctx->mutex); | |
1161 | put_ctx(ctx); | |
1162 | } | |
1163 | ||
211de6eb PZ |
1164 | /* |
1165 | * This must be done under the ctx->lock, such as to serialize against | |
1166 | * context_equiv(), therefore we cannot call put_ctx() since that might end up | |
1167 | * calling scheduler related locks and ctx->lock nests inside those. | |
1168 | */ | |
1169 | static __must_check struct perf_event_context * | |
1170 | unclone_ctx(struct perf_event_context *ctx) | |
71a851b4 | 1171 | { |
211de6eb PZ |
1172 | struct perf_event_context *parent_ctx = ctx->parent_ctx; |
1173 | ||
1174 | lockdep_assert_held(&ctx->lock); | |
1175 | ||
1176 | if (parent_ctx) | |
71a851b4 | 1177 | ctx->parent_ctx = NULL; |
5a3126d4 | 1178 | ctx->generation++; |
211de6eb PZ |
1179 | |
1180 | return parent_ctx; | |
71a851b4 PZ |
1181 | } |
1182 | ||
6844c09d ACM |
1183 | static u32 perf_event_pid(struct perf_event *event, struct task_struct *p) |
1184 | { | |
1185 | /* | |
1186 | * only top level events have the pid namespace they were created in | |
1187 | */ | |
1188 | if (event->parent) | |
1189 | event = event->parent; | |
1190 | ||
1191 | return task_tgid_nr_ns(p, event->ns); | |
1192 | } | |
1193 | ||
1194 | static u32 perf_event_tid(struct perf_event *event, struct task_struct *p) | |
1195 | { | |
1196 | /* | |
1197 | * only top level events have the pid namespace they were created in | |
1198 | */ | |
1199 | if (event->parent) | |
1200 | event = event->parent; | |
1201 | ||
1202 | return task_pid_nr_ns(p, event->ns); | |
1203 | } | |
1204 | ||
7f453c24 | 1205 | /* |
cdd6c482 | 1206 | * If we inherit events we want to return the parent event id |
7f453c24 PZ |
1207 | * to userspace. |
1208 | */ | |
cdd6c482 | 1209 | static u64 primary_event_id(struct perf_event *event) |
7f453c24 | 1210 | { |
cdd6c482 | 1211 | u64 id = event->id; |
7f453c24 | 1212 | |
cdd6c482 IM |
1213 | if (event->parent) |
1214 | id = event->parent->id; | |
7f453c24 PZ |
1215 | |
1216 | return id; | |
1217 | } | |
1218 | ||
25346b93 | 1219 | /* |
cdd6c482 | 1220 | * Get the perf_event_context for a task and lock it. |
63b6da39 | 1221 | * |
25346b93 PM |
1222 | * This has to cope with with the fact that until it is locked, |
1223 | * the context could get moved to another task. | |
1224 | */ | |
cdd6c482 | 1225 | static struct perf_event_context * |
8dc85d54 | 1226 | perf_lock_task_context(struct task_struct *task, int ctxn, unsigned long *flags) |
25346b93 | 1227 | { |
cdd6c482 | 1228 | struct perf_event_context *ctx; |
25346b93 | 1229 | |
9ed6060d | 1230 | retry: |
058ebd0e PZ |
1231 | /* |
1232 | * One of the few rules of preemptible RCU is that one cannot do | |
1233 | * rcu_read_unlock() while holding a scheduler (or nested) lock when | |
2fd59077 | 1234 | * part of the read side critical section was irqs-enabled -- see |
058ebd0e PZ |
1235 | * rcu_read_unlock_special(). |
1236 | * | |
1237 | * Since ctx->lock nests under rq->lock we must ensure the entire read | |
2fd59077 | 1238 | * side critical section has interrupts disabled. |
058ebd0e | 1239 | */ |
2fd59077 | 1240 | local_irq_save(*flags); |
058ebd0e | 1241 | rcu_read_lock(); |
8dc85d54 | 1242 | ctx = rcu_dereference(task->perf_event_ctxp[ctxn]); |
25346b93 PM |
1243 | if (ctx) { |
1244 | /* | |
1245 | * If this context is a clone of another, it might | |
1246 | * get swapped for another underneath us by | |
cdd6c482 | 1247 | * perf_event_task_sched_out, though the |
25346b93 PM |
1248 | * rcu_read_lock() protects us from any context |
1249 | * getting freed. Lock the context and check if it | |
1250 | * got swapped before we could get the lock, and retry | |
1251 | * if so. If we locked the right context, then it | |
1252 | * can't get swapped on us any more. | |
1253 | */ | |
2fd59077 | 1254 | raw_spin_lock(&ctx->lock); |
8dc85d54 | 1255 | if (ctx != rcu_dereference(task->perf_event_ctxp[ctxn])) { |
2fd59077 | 1256 | raw_spin_unlock(&ctx->lock); |
058ebd0e | 1257 | rcu_read_unlock(); |
2fd59077 | 1258 | local_irq_restore(*flags); |
25346b93 PM |
1259 | goto retry; |
1260 | } | |
b49a9e7e | 1261 | |
63b6da39 PZ |
1262 | if (ctx->task == TASK_TOMBSTONE || |
1263 | !atomic_inc_not_zero(&ctx->refcount)) { | |
2fd59077 | 1264 | raw_spin_unlock(&ctx->lock); |
b49a9e7e | 1265 | ctx = NULL; |
828b6f0e PZ |
1266 | } else { |
1267 | WARN_ON_ONCE(ctx->task != task); | |
b49a9e7e | 1268 | } |
25346b93 PM |
1269 | } |
1270 | rcu_read_unlock(); | |
2fd59077 PM |
1271 | if (!ctx) |
1272 | local_irq_restore(*flags); | |
25346b93 PM |
1273 | return ctx; |
1274 | } | |
1275 | ||
1276 | /* | |
1277 | * Get the context for a task and increment its pin_count so it | |
1278 | * can't get swapped to another task. This also increments its | |
1279 | * reference count so that the context can't get freed. | |
1280 | */ | |
8dc85d54 PZ |
1281 | static struct perf_event_context * |
1282 | perf_pin_task_context(struct task_struct *task, int ctxn) | |
25346b93 | 1283 | { |
cdd6c482 | 1284 | struct perf_event_context *ctx; |
25346b93 PM |
1285 | unsigned long flags; |
1286 | ||
8dc85d54 | 1287 | ctx = perf_lock_task_context(task, ctxn, &flags); |
25346b93 PM |
1288 | if (ctx) { |
1289 | ++ctx->pin_count; | |
e625cce1 | 1290 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1291 | } |
1292 | return ctx; | |
1293 | } | |
1294 | ||
cdd6c482 | 1295 | static void perf_unpin_context(struct perf_event_context *ctx) |
25346b93 PM |
1296 | { |
1297 | unsigned long flags; | |
1298 | ||
e625cce1 | 1299 | raw_spin_lock_irqsave(&ctx->lock, flags); |
25346b93 | 1300 | --ctx->pin_count; |
e625cce1 | 1301 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1302 | } |
1303 | ||
f67218c3 PZ |
1304 | /* |
1305 | * Update the record of the current time in a context. | |
1306 | */ | |
1307 | static void update_context_time(struct perf_event_context *ctx) | |
1308 | { | |
1309 | u64 now = perf_clock(); | |
1310 | ||
1311 | ctx->time += now - ctx->timestamp; | |
1312 | ctx->timestamp = now; | |
1313 | } | |
1314 | ||
4158755d SE |
1315 | static u64 perf_event_time(struct perf_event *event) |
1316 | { | |
1317 | struct perf_event_context *ctx = event->ctx; | |
e5d1367f SE |
1318 | |
1319 | if (is_cgroup_event(event)) | |
1320 | return perf_cgroup_event_time(event); | |
1321 | ||
4158755d SE |
1322 | return ctx ? ctx->time : 0; |
1323 | } | |
1324 | ||
f67218c3 PZ |
1325 | /* |
1326 | * Update the total_time_enabled and total_time_running fields for a event. | |
1327 | */ | |
1328 | static void update_event_times(struct perf_event *event) | |
1329 | { | |
1330 | struct perf_event_context *ctx = event->ctx; | |
1331 | u64 run_end; | |
1332 | ||
3cbaa590 PZ |
1333 | lockdep_assert_held(&ctx->lock); |
1334 | ||
f67218c3 PZ |
1335 | if (event->state < PERF_EVENT_STATE_INACTIVE || |
1336 | event->group_leader->state < PERF_EVENT_STATE_INACTIVE) | |
1337 | return; | |
3cbaa590 | 1338 | |
e5d1367f SE |
1339 | /* |
1340 | * in cgroup mode, time_enabled represents | |
1341 | * the time the event was enabled AND active | |
1342 | * tasks were in the monitored cgroup. This is | |
1343 | * independent of the activity of the context as | |
1344 | * there may be a mix of cgroup and non-cgroup events. | |
1345 | * | |
1346 | * That is why we treat cgroup events differently | |
1347 | * here. | |
1348 | */ | |
1349 | if (is_cgroup_event(event)) | |
46cd6a7f | 1350 | run_end = perf_cgroup_event_time(event); |
e5d1367f SE |
1351 | else if (ctx->is_active) |
1352 | run_end = ctx->time; | |
acd1d7c1 PZ |
1353 | else |
1354 | run_end = event->tstamp_stopped; | |
1355 | ||
1356 | event->total_time_enabled = run_end - event->tstamp_enabled; | |
f67218c3 PZ |
1357 | |
1358 | if (event->state == PERF_EVENT_STATE_INACTIVE) | |
1359 | run_end = event->tstamp_stopped; | |
1360 | else | |
4158755d | 1361 | run_end = perf_event_time(event); |
f67218c3 PZ |
1362 | |
1363 | event->total_time_running = run_end - event->tstamp_running; | |
e5d1367f | 1364 | |
f67218c3 PZ |
1365 | } |
1366 | ||
96c21a46 PZ |
1367 | /* |
1368 | * Update total_time_enabled and total_time_running for all events in a group. | |
1369 | */ | |
1370 | static void update_group_times(struct perf_event *leader) | |
1371 | { | |
1372 | struct perf_event *event; | |
1373 | ||
1374 | update_event_times(leader); | |
1375 | list_for_each_entry(event, &leader->sibling_list, group_entry) | |
1376 | update_event_times(event); | |
1377 | } | |
1378 | ||
889ff015 FW |
1379 | static struct list_head * |
1380 | ctx_group_list(struct perf_event *event, struct perf_event_context *ctx) | |
1381 | { | |
1382 | if (event->attr.pinned) | |
1383 | return &ctx->pinned_groups; | |
1384 | else | |
1385 | return &ctx->flexible_groups; | |
1386 | } | |
1387 | ||
fccc714b | 1388 | /* |
cdd6c482 | 1389 | * Add a event from the lists for its context. |
fccc714b PZ |
1390 | * Must be called with ctx->mutex and ctx->lock held. |
1391 | */ | |
04289bb9 | 1392 | static void |
cdd6c482 | 1393 | list_add_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1394 | { |
c994d613 PZ |
1395 | lockdep_assert_held(&ctx->lock); |
1396 | ||
8a49542c PZ |
1397 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); |
1398 | event->attach_state |= PERF_ATTACH_CONTEXT; | |
04289bb9 IM |
1399 | |
1400 | /* | |
8a49542c PZ |
1401 | * If we're a stand alone event or group leader, we go to the context |
1402 | * list, group events are kept attached to the group so that | |
1403 | * perf_group_detach can, at all times, locate all siblings. | |
04289bb9 | 1404 | */ |
8a49542c | 1405 | if (event->group_leader == event) { |
889ff015 FW |
1406 | struct list_head *list; |
1407 | ||
d6f962b5 FW |
1408 | if (is_software_event(event)) |
1409 | event->group_flags |= PERF_GROUP_SOFTWARE; | |
1410 | ||
889ff015 FW |
1411 | list = ctx_group_list(event, ctx); |
1412 | list_add_tail(&event->group_entry, list); | |
5c148194 | 1413 | } |
592903cd | 1414 | |
08309379 | 1415 | if (is_cgroup_event(event)) |
e5d1367f | 1416 | ctx->nr_cgroups++; |
e5d1367f | 1417 | |
cdd6c482 IM |
1418 | list_add_rcu(&event->event_entry, &ctx->event_list); |
1419 | ctx->nr_events++; | |
1420 | if (event->attr.inherit_stat) | |
bfbd3381 | 1421 | ctx->nr_stat++; |
5a3126d4 PZ |
1422 | |
1423 | ctx->generation++; | |
04289bb9 IM |
1424 | } |
1425 | ||
0231bb53 JO |
1426 | /* |
1427 | * Initialize event state based on the perf_event_attr::disabled. | |
1428 | */ | |
1429 | static inline void perf_event__state_init(struct perf_event *event) | |
1430 | { | |
1431 | event->state = event->attr.disabled ? PERF_EVENT_STATE_OFF : | |
1432 | PERF_EVENT_STATE_INACTIVE; | |
1433 | } | |
1434 | ||
a723968c | 1435 | static void __perf_event_read_size(struct perf_event *event, int nr_siblings) |
c320c7b7 ACM |
1436 | { |
1437 | int entry = sizeof(u64); /* value */ | |
1438 | int size = 0; | |
1439 | int nr = 1; | |
1440 | ||
1441 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
1442 | size += sizeof(u64); | |
1443 | ||
1444 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
1445 | size += sizeof(u64); | |
1446 | ||
1447 | if (event->attr.read_format & PERF_FORMAT_ID) | |
1448 | entry += sizeof(u64); | |
1449 | ||
1450 | if (event->attr.read_format & PERF_FORMAT_GROUP) { | |
a723968c | 1451 | nr += nr_siblings; |
c320c7b7 ACM |
1452 | size += sizeof(u64); |
1453 | } | |
1454 | ||
1455 | size += entry * nr; | |
1456 | event->read_size = size; | |
1457 | } | |
1458 | ||
a723968c | 1459 | static void __perf_event_header_size(struct perf_event *event, u64 sample_type) |
c320c7b7 ACM |
1460 | { |
1461 | struct perf_sample_data *data; | |
c320c7b7 ACM |
1462 | u16 size = 0; |
1463 | ||
c320c7b7 ACM |
1464 | if (sample_type & PERF_SAMPLE_IP) |
1465 | size += sizeof(data->ip); | |
1466 | ||
6844c09d ACM |
1467 | if (sample_type & PERF_SAMPLE_ADDR) |
1468 | size += sizeof(data->addr); | |
1469 | ||
1470 | if (sample_type & PERF_SAMPLE_PERIOD) | |
1471 | size += sizeof(data->period); | |
1472 | ||
c3feedf2 AK |
1473 | if (sample_type & PERF_SAMPLE_WEIGHT) |
1474 | size += sizeof(data->weight); | |
1475 | ||
6844c09d ACM |
1476 | if (sample_type & PERF_SAMPLE_READ) |
1477 | size += event->read_size; | |
1478 | ||
d6be9ad6 SE |
1479 | if (sample_type & PERF_SAMPLE_DATA_SRC) |
1480 | size += sizeof(data->data_src.val); | |
1481 | ||
fdfbbd07 AK |
1482 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
1483 | size += sizeof(data->txn); | |
1484 | ||
6844c09d ACM |
1485 | event->header_size = size; |
1486 | } | |
1487 | ||
a723968c PZ |
1488 | /* |
1489 | * Called at perf_event creation and when events are attached/detached from a | |
1490 | * group. | |
1491 | */ | |
1492 | static void perf_event__header_size(struct perf_event *event) | |
1493 | { | |
1494 | __perf_event_read_size(event, | |
1495 | event->group_leader->nr_siblings); | |
1496 | __perf_event_header_size(event, event->attr.sample_type); | |
1497 | } | |
1498 | ||
6844c09d ACM |
1499 | static void perf_event__id_header_size(struct perf_event *event) |
1500 | { | |
1501 | struct perf_sample_data *data; | |
1502 | u64 sample_type = event->attr.sample_type; | |
1503 | u16 size = 0; | |
1504 | ||
c320c7b7 ACM |
1505 | if (sample_type & PERF_SAMPLE_TID) |
1506 | size += sizeof(data->tid_entry); | |
1507 | ||
1508 | if (sample_type & PERF_SAMPLE_TIME) | |
1509 | size += sizeof(data->time); | |
1510 | ||
ff3d527c AH |
1511 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
1512 | size += sizeof(data->id); | |
1513 | ||
c320c7b7 ACM |
1514 | if (sample_type & PERF_SAMPLE_ID) |
1515 | size += sizeof(data->id); | |
1516 | ||
1517 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
1518 | size += sizeof(data->stream_id); | |
1519 | ||
1520 | if (sample_type & PERF_SAMPLE_CPU) | |
1521 | size += sizeof(data->cpu_entry); | |
1522 | ||
6844c09d | 1523 | event->id_header_size = size; |
c320c7b7 ACM |
1524 | } |
1525 | ||
a723968c PZ |
1526 | static bool perf_event_validate_size(struct perf_event *event) |
1527 | { | |
1528 | /* | |
1529 | * The values computed here will be over-written when we actually | |
1530 | * attach the event. | |
1531 | */ | |
1532 | __perf_event_read_size(event, event->group_leader->nr_siblings + 1); | |
1533 | __perf_event_header_size(event, event->attr.sample_type & ~PERF_SAMPLE_READ); | |
1534 | perf_event__id_header_size(event); | |
1535 | ||
1536 | /* | |
1537 | * Sum the lot; should not exceed the 64k limit we have on records. | |
1538 | * Conservative limit to allow for callchains and other variable fields. | |
1539 | */ | |
1540 | if (event->read_size + event->header_size + | |
1541 | event->id_header_size + sizeof(struct perf_event_header) >= 16*1024) | |
1542 | return false; | |
1543 | ||
1544 | return true; | |
1545 | } | |
1546 | ||
8a49542c PZ |
1547 | static void perf_group_attach(struct perf_event *event) |
1548 | { | |
c320c7b7 | 1549 | struct perf_event *group_leader = event->group_leader, *pos; |
8a49542c | 1550 | |
74c3337c PZ |
1551 | /* |
1552 | * We can have double attach due to group movement in perf_event_open. | |
1553 | */ | |
1554 | if (event->attach_state & PERF_ATTACH_GROUP) | |
1555 | return; | |
1556 | ||
8a49542c PZ |
1557 | event->attach_state |= PERF_ATTACH_GROUP; |
1558 | ||
1559 | if (group_leader == event) | |
1560 | return; | |
1561 | ||
652884fe PZ |
1562 | WARN_ON_ONCE(group_leader->ctx != event->ctx); |
1563 | ||
8a49542c PZ |
1564 | if (group_leader->group_flags & PERF_GROUP_SOFTWARE && |
1565 | !is_software_event(event)) | |
1566 | group_leader->group_flags &= ~PERF_GROUP_SOFTWARE; | |
1567 | ||
1568 | list_add_tail(&event->group_entry, &group_leader->sibling_list); | |
1569 | group_leader->nr_siblings++; | |
c320c7b7 ACM |
1570 | |
1571 | perf_event__header_size(group_leader); | |
1572 | ||
1573 | list_for_each_entry(pos, &group_leader->sibling_list, group_entry) | |
1574 | perf_event__header_size(pos); | |
8a49542c PZ |
1575 | } |
1576 | ||
a63eaf34 | 1577 | /* |
cdd6c482 | 1578 | * Remove a event from the lists for its context. |
fccc714b | 1579 | * Must be called with ctx->mutex and ctx->lock held. |
a63eaf34 | 1580 | */ |
04289bb9 | 1581 | static void |
cdd6c482 | 1582 | list_del_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1583 | { |
68cacd29 | 1584 | struct perf_cpu_context *cpuctx; |
652884fe PZ |
1585 | |
1586 | WARN_ON_ONCE(event->ctx != ctx); | |
1587 | lockdep_assert_held(&ctx->lock); | |
1588 | ||
8a49542c PZ |
1589 | /* |
1590 | * We can have double detach due to exit/hot-unplug + close. | |
1591 | */ | |
1592 | if (!(event->attach_state & PERF_ATTACH_CONTEXT)) | |
a63eaf34 | 1593 | return; |
8a49542c PZ |
1594 | |
1595 | event->attach_state &= ~PERF_ATTACH_CONTEXT; | |
1596 | ||
68cacd29 | 1597 | if (is_cgroup_event(event)) { |
e5d1367f | 1598 | ctx->nr_cgroups--; |
70a01657 PZ |
1599 | /* |
1600 | * Because cgroup events are always per-cpu events, this will | |
1601 | * always be called from the right CPU. | |
1602 | */ | |
68cacd29 SE |
1603 | cpuctx = __get_cpu_context(ctx); |
1604 | /* | |
70a01657 PZ |
1605 | * If there are no more cgroup events then clear cgrp to avoid |
1606 | * stale pointer in update_cgrp_time_from_cpuctx(). | |
68cacd29 SE |
1607 | */ |
1608 | if (!ctx->nr_cgroups) | |
1609 | cpuctx->cgrp = NULL; | |
1610 | } | |
e5d1367f | 1611 | |
cdd6c482 IM |
1612 | ctx->nr_events--; |
1613 | if (event->attr.inherit_stat) | |
bfbd3381 | 1614 | ctx->nr_stat--; |
8bc20959 | 1615 | |
cdd6c482 | 1616 | list_del_rcu(&event->event_entry); |
04289bb9 | 1617 | |
8a49542c PZ |
1618 | if (event->group_leader == event) |
1619 | list_del_init(&event->group_entry); | |
5c148194 | 1620 | |
96c21a46 | 1621 | update_group_times(event); |
b2e74a26 SE |
1622 | |
1623 | /* | |
1624 | * If event was in error state, then keep it | |
1625 | * that way, otherwise bogus counts will be | |
1626 | * returned on read(). The only way to get out | |
1627 | * of error state is by explicit re-enabling | |
1628 | * of the event | |
1629 | */ | |
1630 | if (event->state > PERF_EVENT_STATE_OFF) | |
1631 | event->state = PERF_EVENT_STATE_OFF; | |
5a3126d4 PZ |
1632 | |
1633 | ctx->generation++; | |
050735b0 PZ |
1634 | } |
1635 | ||
8a49542c | 1636 | static void perf_group_detach(struct perf_event *event) |
050735b0 PZ |
1637 | { |
1638 | struct perf_event *sibling, *tmp; | |
8a49542c PZ |
1639 | struct list_head *list = NULL; |
1640 | ||
1641 | /* | |
1642 | * We can have double detach due to exit/hot-unplug + close. | |
1643 | */ | |
1644 | if (!(event->attach_state & PERF_ATTACH_GROUP)) | |
1645 | return; | |
1646 | ||
1647 | event->attach_state &= ~PERF_ATTACH_GROUP; | |
1648 | ||
1649 | /* | |
1650 | * If this is a sibling, remove it from its group. | |
1651 | */ | |
1652 | if (event->group_leader != event) { | |
1653 | list_del_init(&event->group_entry); | |
1654 | event->group_leader->nr_siblings--; | |
c320c7b7 | 1655 | goto out; |
8a49542c PZ |
1656 | } |
1657 | ||
1658 | if (!list_empty(&event->group_entry)) | |
1659 | list = &event->group_entry; | |
2e2af50b | 1660 | |
04289bb9 | 1661 | /* |
cdd6c482 IM |
1662 | * If this was a group event with sibling events then |
1663 | * upgrade the siblings to singleton events by adding them | |
8a49542c | 1664 | * to whatever list we are on. |
04289bb9 | 1665 | */ |
cdd6c482 | 1666 | list_for_each_entry_safe(sibling, tmp, &event->sibling_list, group_entry) { |
8a49542c PZ |
1667 | if (list) |
1668 | list_move_tail(&sibling->group_entry, list); | |
04289bb9 | 1669 | sibling->group_leader = sibling; |
d6f962b5 FW |
1670 | |
1671 | /* Inherit group flags from the previous leader */ | |
1672 | sibling->group_flags = event->group_flags; | |
652884fe PZ |
1673 | |
1674 | WARN_ON_ONCE(sibling->ctx != event->ctx); | |
04289bb9 | 1675 | } |
c320c7b7 ACM |
1676 | |
1677 | out: | |
1678 | perf_event__header_size(event->group_leader); | |
1679 | ||
1680 | list_for_each_entry(tmp, &event->group_leader->sibling_list, group_entry) | |
1681 | perf_event__header_size(tmp); | |
04289bb9 IM |
1682 | } |
1683 | ||
fadfe7be JO |
1684 | static bool is_orphaned_event(struct perf_event *event) |
1685 | { | |
a69b0ca4 | 1686 | return event->state == PERF_EVENT_STATE_DEAD; |
fadfe7be JO |
1687 | } |
1688 | ||
2c81a647 | 1689 | static inline int __pmu_filter_match(struct perf_event *event) |
66eb579e MR |
1690 | { |
1691 | struct pmu *pmu = event->pmu; | |
1692 | return pmu->filter_match ? pmu->filter_match(event) : 1; | |
1693 | } | |
1694 | ||
2c81a647 MR |
1695 | /* |
1696 | * Check whether we should attempt to schedule an event group based on | |
1697 | * PMU-specific filtering. An event group can consist of HW and SW events, | |
1698 | * potentially with a SW leader, so we must check all the filters, to | |
1699 | * determine whether a group is schedulable: | |
1700 | */ | |
1701 | static inline int pmu_filter_match(struct perf_event *event) | |
1702 | { | |
1703 | struct perf_event *child; | |
1704 | ||
1705 | if (!__pmu_filter_match(event)) | |
1706 | return 0; | |
1707 | ||
1708 | list_for_each_entry(child, &event->sibling_list, group_entry) { | |
1709 | if (!__pmu_filter_match(child)) | |
1710 | return 0; | |
1711 | } | |
1712 | ||
1713 | return 1; | |
1714 | } | |
1715 | ||
fa66f07a SE |
1716 | static inline int |
1717 | event_filter_match(struct perf_event *event) | |
1718 | { | |
0b8f1e2e PZ |
1719 | return (event->cpu == -1 || event->cpu == smp_processor_id()) && |
1720 | perf_cgroup_match(event) && pmu_filter_match(event); | |
fa66f07a SE |
1721 | } |
1722 | ||
9ffcfa6f SE |
1723 | static void |
1724 | event_sched_out(struct perf_event *event, | |
3b6f9e5c | 1725 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 1726 | struct perf_event_context *ctx) |
3b6f9e5c | 1727 | { |
4158755d | 1728 | u64 tstamp = perf_event_time(event); |
fa66f07a | 1729 | u64 delta; |
652884fe PZ |
1730 | |
1731 | WARN_ON_ONCE(event->ctx != ctx); | |
1732 | lockdep_assert_held(&ctx->lock); | |
1733 | ||
fa66f07a SE |
1734 | /* |
1735 | * An event which could not be activated because of | |
1736 | * filter mismatch still needs to have its timings | |
1737 | * maintained, otherwise bogus information is return | |
1738 | * via read() for time_enabled, time_running: | |
1739 | */ | |
0b8f1e2e PZ |
1740 | if (event->state == PERF_EVENT_STATE_INACTIVE && |
1741 | !event_filter_match(event)) { | |
e5d1367f | 1742 | delta = tstamp - event->tstamp_stopped; |
fa66f07a | 1743 | event->tstamp_running += delta; |
4158755d | 1744 | event->tstamp_stopped = tstamp; |
fa66f07a SE |
1745 | } |
1746 | ||
cdd6c482 | 1747 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
9ffcfa6f | 1748 | return; |
3b6f9e5c | 1749 | |
44377277 AS |
1750 | perf_pmu_disable(event->pmu); |
1751 | ||
28a967c3 PZ |
1752 | event->tstamp_stopped = tstamp; |
1753 | event->pmu->del(event, 0); | |
1754 | event->oncpu = -1; | |
cdd6c482 IM |
1755 | event->state = PERF_EVENT_STATE_INACTIVE; |
1756 | if (event->pending_disable) { | |
1757 | event->pending_disable = 0; | |
1758 | event->state = PERF_EVENT_STATE_OFF; | |
970892a9 | 1759 | } |
3b6f9e5c | 1760 | |
cdd6c482 | 1761 | if (!is_software_event(event)) |
3b6f9e5c | 1762 | cpuctx->active_oncpu--; |
2fde4f94 MR |
1763 | if (!--ctx->nr_active) |
1764 | perf_event_ctx_deactivate(ctx); | |
0f5a2601 PZ |
1765 | if (event->attr.freq && event->attr.sample_freq) |
1766 | ctx->nr_freq--; | |
cdd6c482 | 1767 | if (event->attr.exclusive || !cpuctx->active_oncpu) |
3b6f9e5c | 1768 | cpuctx->exclusive = 0; |
44377277 AS |
1769 | |
1770 | perf_pmu_enable(event->pmu); | |
3b6f9e5c PM |
1771 | } |
1772 | ||
d859e29f | 1773 | static void |
cdd6c482 | 1774 | group_sched_out(struct perf_event *group_event, |
d859e29f | 1775 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 1776 | struct perf_event_context *ctx) |
d859e29f | 1777 | { |
cdd6c482 | 1778 | struct perf_event *event; |
fa66f07a | 1779 | int state = group_event->state; |
d859e29f | 1780 | |
cdd6c482 | 1781 | event_sched_out(group_event, cpuctx, ctx); |
d859e29f PM |
1782 | |
1783 | /* | |
1784 | * Schedule out siblings (if any): | |
1785 | */ | |
cdd6c482 IM |
1786 | list_for_each_entry(event, &group_event->sibling_list, group_entry) |
1787 | event_sched_out(event, cpuctx, ctx); | |
d859e29f | 1788 | |
fa66f07a | 1789 | if (state == PERF_EVENT_STATE_ACTIVE && group_event->attr.exclusive) |
d859e29f PM |
1790 | cpuctx->exclusive = 0; |
1791 | } | |
1792 | ||
45a0e07a | 1793 | #define DETACH_GROUP 0x01UL |
0017960f | 1794 | |
0793a61d | 1795 | /* |
cdd6c482 | 1796 | * Cross CPU call to remove a performance event |
0793a61d | 1797 | * |
cdd6c482 | 1798 | * We disable the event on the hardware level first. After that we |
0793a61d TG |
1799 | * remove it from the context list. |
1800 | */ | |
fae3fde6 PZ |
1801 | static void |
1802 | __perf_remove_from_context(struct perf_event *event, | |
1803 | struct perf_cpu_context *cpuctx, | |
1804 | struct perf_event_context *ctx, | |
1805 | void *info) | |
0793a61d | 1806 | { |
45a0e07a | 1807 | unsigned long flags = (unsigned long)info; |
0793a61d | 1808 | |
cdd6c482 | 1809 | event_sched_out(event, cpuctx, ctx); |
45a0e07a | 1810 | if (flags & DETACH_GROUP) |
46ce0fe9 | 1811 | perf_group_detach(event); |
cdd6c482 | 1812 | list_del_event(event, ctx); |
39a43640 PZ |
1813 | |
1814 | if (!ctx->nr_events && ctx->is_active) { | |
64ce3126 | 1815 | ctx->is_active = 0; |
39a43640 PZ |
1816 | if (ctx->task) { |
1817 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
1818 | cpuctx->task_ctx = NULL; | |
1819 | } | |
64ce3126 | 1820 | } |
0793a61d TG |
1821 | } |
1822 | ||
0793a61d | 1823 | /* |
cdd6c482 | 1824 | * Remove the event from a task's (or a CPU's) list of events. |
0793a61d | 1825 | * |
cdd6c482 IM |
1826 | * If event->ctx is a cloned context, callers must make sure that |
1827 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 PM |
1828 | * remains valid. This is OK when called from perf_release since |
1829 | * that only calls us on the top-level context, which can't be a clone. | |
cdd6c482 | 1830 | * When called from perf_event_exit_task, it's OK because the |
c93f7669 | 1831 | * context has been detached from its task. |
0793a61d | 1832 | */ |
45a0e07a | 1833 | static void perf_remove_from_context(struct perf_event *event, unsigned long flags) |
0793a61d | 1834 | { |
fae3fde6 | 1835 | lockdep_assert_held(&event->ctx->mutex); |
0793a61d | 1836 | |
45a0e07a | 1837 | event_function_call(event, __perf_remove_from_context, (void *)flags); |
0793a61d TG |
1838 | } |
1839 | ||
d859e29f | 1840 | /* |
cdd6c482 | 1841 | * Cross CPU call to disable a performance event |
d859e29f | 1842 | */ |
fae3fde6 PZ |
1843 | static void __perf_event_disable(struct perf_event *event, |
1844 | struct perf_cpu_context *cpuctx, | |
1845 | struct perf_event_context *ctx, | |
1846 | void *info) | |
7b648018 | 1847 | { |
fae3fde6 PZ |
1848 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
1849 | return; | |
7b648018 | 1850 | |
fae3fde6 PZ |
1851 | update_context_time(ctx); |
1852 | update_cgrp_time_from_event(event); | |
1853 | update_group_times(event); | |
1854 | if (event == event->group_leader) | |
1855 | group_sched_out(event, cpuctx, ctx); | |
1856 | else | |
1857 | event_sched_out(event, cpuctx, ctx); | |
1858 | event->state = PERF_EVENT_STATE_OFF; | |
7b648018 PZ |
1859 | } |
1860 | ||
d859e29f | 1861 | /* |
cdd6c482 | 1862 | * Disable a event. |
c93f7669 | 1863 | * |
cdd6c482 IM |
1864 | * If event->ctx is a cloned context, callers must make sure that |
1865 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 1866 | * remains valid. This condition is satisifed when called through |
cdd6c482 IM |
1867 | * perf_event_for_each_child or perf_event_for_each because they |
1868 | * hold the top-level event's child_mutex, so any descendant that | |
8ba289b8 PZ |
1869 | * goes to exit will block in perf_event_exit_event(). |
1870 | * | |
cdd6c482 | 1871 | * When called from perf_pending_event it's OK because event->ctx |
c93f7669 | 1872 | * is the current context on this CPU and preemption is disabled, |
cdd6c482 | 1873 | * hence we can't get into perf_event_task_sched_out for this context. |
d859e29f | 1874 | */ |
f63a8daa | 1875 | static void _perf_event_disable(struct perf_event *event) |
d859e29f | 1876 | { |
cdd6c482 | 1877 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 1878 | |
e625cce1 | 1879 | raw_spin_lock_irq(&ctx->lock); |
7b648018 | 1880 | if (event->state <= PERF_EVENT_STATE_OFF) { |
e625cce1 | 1881 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 1882 | return; |
53cfbf59 | 1883 | } |
e625cce1 | 1884 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 1885 | |
fae3fde6 PZ |
1886 | event_function_call(event, __perf_event_disable, NULL); |
1887 | } | |
1888 | ||
1889 | void perf_event_disable_local(struct perf_event *event) | |
1890 | { | |
1891 | event_function_local(event, __perf_event_disable, NULL); | |
d859e29f | 1892 | } |
f63a8daa PZ |
1893 | |
1894 | /* | |
1895 | * Strictly speaking kernel users cannot create groups and therefore this | |
1896 | * interface does not need the perf_event_ctx_lock() magic. | |
1897 | */ | |
1898 | void perf_event_disable(struct perf_event *event) | |
1899 | { | |
1900 | struct perf_event_context *ctx; | |
1901 | ||
1902 | ctx = perf_event_ctx_lock(event); | |
1903 | _perf_event_disable(event); | |
1904 | perf_event_ctx_unlock(event, ctx); | |
1905 | } | |
dcfce4a0 | 1906 | EXPORT_SYMBOL_GPL(perf_event_disable); |
d859e29f | 1907 | |
e5d1367f SE |
1908 | static void perf_set_shadow_time(struct perf_event *event, |
1909 | struct perf_event_context *ctx, | |
1910 | u64 tstamp) | |
1911 | { | |
1912 | /* | |
1913 | * use the correct time source for the time snapshot | |
1914 | * | |
1915 | * We could get by without this by leveraging the | |
1916 | * fact that to get to this function, the caller | |
1917 | * has most likely already called update_context_time() | |
1918 | * and update_cgrp_time_xx() and thus both timestamp | |
1919 | * are identical (or very close). Given that tstamp is, | |
1920 | * already adjusted for cgroup, we could say that: | |
1921 | * tstamp - ctx->timestamp | |
1922 | * is equivalent to | |
1923 | * tstamp - cgrp->timestamp. | |
1924 | * | |
1925 | * Then, in perf_output_read(), the calculation would | |
1926 | * work with no changes because: | |
1927 | * - event is guaranteed scheduled in | |
1928 | * - no scheduled out in between | |
1929 | * - thus the timestamp would be the same | |
1930 | * | |
1931 | * But this is a bit hairy. | |
1932 | * | |
1933 | * So instead, we have an explicit cgroup call to remain | |
1934 | * within the time time source all along. We believe it | |
1935 | * is cleaner and simpler to understand. | |
1936 | */ | |
1937 | if (is_cgroup_event(event)) | |
1938 | perf_cgroup_set_shadow_time(event, tstamp); | |
1939 | else | |
1940 | event->shadow_ctx_time = tstamp - ctx->timestamp; | |
1941 | } | |
1942 | ||
4fe757dd PZ |
1943 | #define MAX_INTERRUPTS (~0ULL) |
1944 | ||
1945 | static void perf_log_throttle(struct perf_event *event, int enable); | |
ec0d7729 | 1946 | static void perf_log_itrace_start(struct perf_event *event); |
4fe757dd | 1947 | |
235c7fc7 | 1948 | static int |
9ffcfa6f | 1949 | event_sched_in(struct perf_event *event, |
235c7fc7 | 1950 | struct perf_cpu_context *cpuctx, |
6e37738a | 1951 | struct perf_event_context *ctx) |
235c7fc7 | 1952 | { |
4158755d | 1953 | u64 tstamp = perf_event_time(event); |
44377277 | 1954 | int ret = 0; |
4158755d | 1955 | |
63342411 PZ |
1956 | lockdep_assert_held(&ctx->lock); |
1957 | ||
cdd6c482 | 1958 | if (event->state <= PERF_EVENT_STATE_OFF) |
235c7fc7 IM |
1959 | return 0; |
1960 | ||
95ff4ca2 AS |
1961 | WRITE_ONCE(event->oncpu, smp_processor_id()); |
1962 | /* | |
1963 | * Order event::oncpu write to happen before the ACTIVE state | |
1964 | * is visible. | |
1965 | */ | |
1966 | smp_wmb(); | |
1967 | WRITE_ONCE(event->state, PERF_EVENT_STATE_ACTIVE); | |
4fe757dd PZ |
1968 | |
1969 | /* | |
1970 | * Unthrottle events, since we scheduled we might have missed several | |
1971 | * ticks already, also for a heavily scheduling task there is little | |
1972 | * guarantee it'll get a tick in a timely manner. | |
1973 | */ | |
1974 | if (unlikely(event->hw.interrupts == MAX_INTERRUPTS)) { | |
1975 | perf_log_throttle(event, 1); | |
1976 | event->hw.interrupts = 0; | |
1977 | } | |
1978 | ||
235c7fc7 IM |
1979 | /* |
1980 | * The new state must be visible before we turn it on in the hardware: | |
1981 | */ | |
1982 | smp_wmb(); | |
1983 | ||
44377277 AS |
1984 | perf_pmu_disable(event->pmu); |
1985 | ||
72f669c0 SL |
1986 | perf_set_shadow_time(event, ctx, tstamp); |
1987 | ||
ec0d7729 AS |
1988 | perf_log_itrace_start(event); |
1989 | ||
a4eaf7f1 | 1990 | if (event->pmu->add(event, PERF_EF_START)) { |
cdd6c482 IM |
1991 | event->state = PERF_EVENT_STATE_INACTIVE; |
1992 | event->oncpu = -1; | |
44377277 AS |
1993 | ret = -EAGAIN; |
1994 | goto out; | |
235c7fc7 IM |
1995 | } |
1996 | ||
00a2916f PZ |
1997 | event->tstamp_running += tstamp - event->tstamp_stopped; |
1998 | ||
cdd6c482 | 1999 | if (!is_software_event(event)) |
3b6f9e5c | 2000 | cpuctx->active_oncpu++; |
2fde4f94 MR |
2001 | if (!ctx->nr_active++) |
2002 | perf_event_ctx_activate(ctx); | |
0f5a2601 PZ |
2003 | if (event->attr.freq && event->attr.sample_freq) |
2004 | ctx->nr_freq++; | |
235c7fc7 | 2005 | |
cdd6c482 | 2006 | if (event->attr.exclusive) |
3b6f9e5c PM |
2007 | cpuctx->exclusive = 1; |
2008 | ||
44377277 AS |
2009 | out: |
2010 | perf_pmu_enable(event->pmu); | |
2011 | ||
2012 | return ret; | |
235c7fc7 IM |
2013 | } |
2014 | ||
6751b71e | 2015 | static int |
cdd6c482 | 2016 | group_sched_in(struct perf_event *group_event, |
6751b71e | 2017 | struct perf_cpu_context *cpuctx, |
6e37738a | 2018 | struct perf_event_context *ctx) |
6751b71e | 2019 | { |
6bde9b6c | 2020 | struct perf_event *event, *partial_group = NULL; |
4a234593 | 2021 | struct pmu *pmu = ctx->pmu; |
d7842da4 SE |
2022 | u64 now = ctx->time; |
2023 | bool simulate = false; | |
6751b71e | 2024 | |
cdd6c482 | 2025 | if (group_event->state == PERF_EVENT_STATE_OFF) |
6751b71e PM |
2026 | return 0; |
2027 | ||
fbbe0701 | 2028 | pmu->start_txn(pmu, PERF_PMU_TXN_ADD); |
6bde9b6c | 2029 | |
9ffcfa6f | 2030 | if (event_sched_in(group_event, cpuctx, ctx)) { |
ad5133b7 | 2031 | pmu->cancel_txn(pmu); |
272325c4 | 2032 | perf_mux_hrtimer_restart(cpuctx); |
6751b71e | 2033 | return -EAGAIN; |
90151c35 | 2034 | } |
6751b71e PM |
2035 | |
2036 | /* | |
2037 | * Schedule in siblings as one group (if any): | |
2038 | */ | |
cdd6c482 | 2039 | list_for_each_entry(event, &group_event->sibling_list, group_entry) { |
9ffcfa6f | 2040 | if (event_sched_in(event, cpuctx, ctx)) { |
cdd6c482 | 2041 | partial_group = event; |
6751b71e PM |
2042 | goto group_error; |
2043 | } | |
2044 | } | |
2045 | ||
9ffcfa6f | 2046 | if (!pmu->commit_txn(pmu)) |
6e85158c | 2047 | return 0; |
9ffcfa6f | 2048 | |
6751b71e PM |
2049 | group_error: |
2050 | /* | |
2051 | * Groups can be scheduled in as one unit only, so undo any | |
2052 | * partial group before returning: | |
d7842da4 SE |
2053 | * The events up to the failed event are scheduled out normally, |
2054 | * tstamp_stopped will be updated. | |
2055 | * | |
2056 | * The failed events and the remaining siblings need to have | |
2057 | * their timings updated as if they had gone thru event_sched_in() | |
2058 | * and event_sched_out(). This is required to get consistent timings | |
2059 | * across the group. This also takes care of the case where the group | |
2060 | * could never be scheduled by ensuring tstamp_stopped is set to mark | |
2061 | * the time the event was actually stopped, such that time delta | |
2062 | * calculation in update_event_times() is correct. | |
6751b71e | 2063 | */ |
cdd6c482 IM |
2064 | list_for_each_entry(event, &group_event->sibling_list, group_entry) { |
2065 | if (event == partial_group) | |
d7842da4 SE |
2066 | simulate = true; |
2067 | ||
2068 | if (simulate) { | |
2069 | event->tstamp_running += now - event->tstamp_stopped; | |
2070 | event->tstamp_stopped = now; | |
2071 | } else { | |
2072 | event_sched_out(event, cpuctx, ctx); | |
2073 | } | |
6751b71e | 2074 | } |
9ffcfa6f | 2075 | event_sched_out(group_event, cpuctx, ctx); |
6751b71e | 2076 | |
ad5133b7 | 2077 | pmu->cancel_txn(pmu); |
90151c35 | 2078 | |
272325c4 | 2079 | perf_mux_hrtimer_restart(cpuctx); |
9e630205 | 2080 | |
6751b71e PM |
2081 | return -EAGAIN; |
2082 | } | |
2083 | ||
3b6f9e5c | 2084 | /* |
cdd6c482 | 2085 | * Work out whether we can put this event group on the CPU now. |
3b6f9e5c | 2086 | */ |
cdd6c482 | 2087 | static int group_can_go_on(struct perf_event *event, |
3b6f9e5c PM |
2088 | struct perf_cpu_context *cpuctx, |
2089 | int can_add_hw) | |
2090 | { | |
2091 | /* | |
cdd6c482 | 2092 | * Groups consisting entirely of software events can always go on. |
3b6f9e5c | 2093 | */ |
d6f962b5 | 2094 | if (event->group_flags & PERF_GROUP_SOFTWARE) |
3b6f9e5c PM |
2095 | return 1; |
2096 | /* | |
2097 | * If an exclusive group is already on, no other hardware | |
cdd6c482 | 2098 | * events can go on. |
3b6f9e5c PM |
2099 | */ |
2100 | if (cpuctx->exclusive) | |
2101 | return 0; | |
2102 | /* | |
2103 | * If this group is exclusive and there are already | |
cdd6c482 | 2104 | * events on the CPU, it can't go on. |
3b6f9e5c | 2105 | */ |
cdd6c482 | 2106 | if (event->attr.exclusive && cpuctx->active_oncpu) |
3b6f9e5c PM |
2107 | return 0; |
2108 | /* | |
2109 | * Otherwise, try to add it if all previous groups were able | |
2110 | * to go on. | |
2111 | */ | |
2112 | return can_add_hw; | |
2113 | } | |
2114 | ||
cdd6c482 IM |
2115 | static void add_event_to_ctx(struct perf_event *event, |
2116 | struct perf_event_context *ctx) | |
53cfbf59 | 2117 | { |
4158755d SE |
2118 | u64 tstamp = perf_event_time(event); |
2119 | ||
cdd6c482 | 2120 | list_add_event(event, ctx); |
8a49542c | 2121 | perf_group_attach(event); |
4158755d SE |
2122 | event->tstamp_enabled = tstamp; |
2123 | event->tstamp_running = tstamp; | |
2124 | event->tstamp_stopped = tstamp; | |
53cfbf59 PM |
2125 | } |
2126 | ||
bd2afa49 PZ |
2127 | static void ctx_sched_out(struct perf_event_context *ctx, |
2128 | struct perf_cpu_context *cpuctx, | |
2129 | enum event_type_t event_type); | |
2c29ef0f PZ |
2130 | static void |
2131 | ctx_sched_in(struct perf_event_context *ctx, | |
2132 | struct perf_cpu_context *cpuctx, | |
2133 | enum event_type_t event_type, | |
2134 | struct task_struct *task); | |
fe4b04fa | 2135 | |
bd2afa49 PZ |
2136 | static void task_ctx_sched_out(struct perf_cpu_context *cpuctx, |
2137 | struct perf_event_context *ctx) | |
2138 | { | |
2139 | if (!cpuctx->task_ctx) | |
2140 | return; | |
2141 | ||
2142 | if (WARN_ON_ONCE(ctx != cpuctx->task_ctx)) | |
2143 | return; | |
2144 | ||
2145 | ctx_sched_out(ctx, cpuctx, EVENT_ALL); | |
2146 | } | |
2147 | ||
dce5855b PZ |
2148 | static void perf_event_sched_in(struct perf_cpu_context *cpuctx, |
2149 | struct perf_event_context *ctx, | |
2150 | struct task_struct *task) | |
2151 | { | |
2152 | cpu_ctx_sched_in(cpuctx, EVENT_PINNED, task); | |
2153 | if (ctx) | |
2154 | ctx_sched_in(ctx, cpuctx, EVENT_PINNED, task); | |
2155 | cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE, task); | |
2156 | if (ctx) | |
2157 | ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE, task); | |
2158 | } | |
2159 | ||
3e349507 PZ |
2160 | static void ctx_resched(struct perf_cpu_context *cpuctx, |
2161 | struct perf_event_context *task_ctx) | |
0017960f | 2162 | { |
3e349507 PZ |
2163 | perf_pmu_disable(cpuctx->ctx.pmu); |
2164 | if (task_ctx) | |
2165 | task_ctx_sched_out(cpuctx, task_ctx); | |
2166 | cpu_ctx_sched_out(cpuctx, EVENT_ALL); | |
2167 | perf_event_sched_in(cpuctx, task_ctx, current); | |
2168 | perf_pmu_enable(cpuctx->ctx.pmu); | |
0017960f PZ |
2169 | } |
2170 | ||
0793a61d | 2171 | /* |
cdd6c482 | 2172 | * Cross CPU call to install and enable a performance event |
682076ae | 2173 | * |
a096309b PZ |
2174 | * Very similar to remote_function() + event_function() but cannot assume that |
2175 | * things like ctx->is_active and cpuctx->task_ctx are set. | |
0793a61d | 2176 | */ |
fe4b04fa | 2177 | static int __perf_install_in_context(void *info) |
0793a61d | 2178 | { |
a096309b PZ |
2179 | struct perf_event *event = info; |
2180 | struct perf_event_context *ctx = event->ctx; | |
108b02cf | 2181 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
2c29ef0f | 2182 | struct perf_event_context *task_ctx = cpuctx->task_ctx; |
a096309b PZ |
2183 | bool activate = true; |
2184 | int ret = 0; | |
0793a61d | 2185 | |
63b6da39 | 2186 | raw_spin_lock(&cpuctx->ctx.lock); |
39a43640 | 2187 | if (ctx->task) { |
b58f6b0d PZ |
2188 | raw_spin_lock(&ctx->lock); |
2189 | task_ctx = ctx; | |
a096309b PZ |
2190 | |
2191 | /* If we're on the wrong CPU, try again */ | |
2192 | if (task_cpu(ctx->task) != smp_processor_id()) { | |
2193 | ret = -ESRCH; | |
63b6da39 | 2194 | goto unlock; |
a096309b | 2195 | } |
b58f6b0d | 2196 | |
39a43640 | 2197 | /* |
a096309b PZ |
2198 | * If we're on the right CPU, see if the task we target is |
2199 | * current, if not we don't have to activate the ctx, a future | |
2200 | * context switch will do that for us. | |
39a43640 | 2201 | */ |
a096309b PZ |
2202 | if (ctx->task != current) |
2203 | activate = false; | |
2204 | else | |
2205 | WARN_ON_ONCE(cpuctx->task_ctx && cpuctx->task_ctx != ctx); | |
2206 | ||
63b6da39 PZ |
2207 | } else if (task_ctx) { |
2208 | raw_spin_lock(&task_ctx->lock); | |
2c29ef0f | 2209 | } |
b58f6b0d | 2210 | |
a096309b PZ |
2211 | if (activate) { |
2212 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); | |
2213 | add_event_to_ctx(event, ctx); | |
2214 | ctx_resched(cpuctx, task_ctx); | |
2215 | } else { | |
2216 | add_event_to_ctx(event, ctx); | |
2217 | } | |
2218 | ||
63b6da39 | 2219 | unlock: |
2c29ef0f | 2220 | perf_ctx_unlock(cpuctx, task_ctx); |
fe4b04fa | 2221 | |
a096309b | 2222 | return ret; |
0793a61d TG |
2223 | } |
2224 | ||
2225 | /* | |
a096309b PZ |
2226 | * Attach a performance event to a context. |
2227 | * | |
2228 | * Very similar to event_function_call, see comment there. | |
0793a61d TG |
2229 | */ |
2230 | static void | |
cdd6c482 IM |
2231 | perf_install_in_context(struct perf_event_context *ctx, |
2232 | struct perf_event *event, | |
0793a61d TG |
2233 | int cpu) |
2234 | { | |
a096309b | 2235 | struct task_struct *task = READ_ONCE(ctx->task); |
39a43640 | 2236 | |
fe4b04fa PZ |
2237 | lockdep_assert_held(&ctx->mutex); |
2238 | ||
0cda4c02 YZ |
2239 | if (event->cpu != -1) |
2240 | event->cpu = cpu; | |
c3f00c70 | 2241 | |
0b8f1e2e PZ |
2242 | /* |
2243 | * Ensures that if we can observe event->ctx, both the event and ctx | |
2244 | * will be 'complete'. See perf_iterate_sb_cpu(). | |
2245 | */ | |
2246 | smp_store_release(&event->ctx, ctx); | |
2247 | ||
a096309b PZ |
2248 | if (!task) { |
2249 | cpu_function_call(cpu, __perf_install_in_context, event); | |
2250 | return; | |
2251 | } | |
2252 | ||
2253 | /* | |
2254 | * Should not happen, we validate the ctx is still alive before calling. | |
2255 | */ | |
2256 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) | |
2257 | return; | |
2258 | ||
39a43640 PZ |
2259 | /* |
2260 | * Installing events is tricky because we cannot rely on ctx->is_active | |
2261 | * to be set in case this is the nr_events 0 -> 1 transition. | |
39a43640 | 2262 | */ |
a096309b | 2263 | again: |
63b6da39 | 2264 | /* |
a096309b PZ |
2265 | * Cannot use task_function_call() because we need to run on the task's |
2266 | * CPU regardless of whether its current or not. | |
63b6da39 | 2267 | */ |
a096309b PZ |
2268 | if (!cpu_function_call(task_cpu(task), __perf_install_in_context, event)) |
2269 | return; | |
2270 | ||
2271 | raw_spin_lock_irq(&ctx->lock); | |
2272 | task = ctx->task; | |
84c4e620 | 2273 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) { |
a096309b PZ |
2274 | /* |
2275 | * Cannot happen because we already checked above (which also | |
2276 | * cannot happen), and we hold ctx->mutex, which serializes us | |
2277 | * against perf_event_exit_task_context(). | |
2278 | */ | |
63b6da39 PZ |
2279 | raw_spin_unlock_irq(&ctx->lock); |
2280 | return; | |
2281 | } | |
39a43640 | 2282 | raw_spin_unlock_irq(&ctx->lock); |
39a43640 | 2283 | /* |
a096309b PZ |
2284 | * Since !ctx->is_active doesn't mean anything, we must IPI |
2285 | * unconditionally. | |
39a43640 | 2286 | */ |
a096309b | 2287 | goto again; |
0793a61d TG |
2288 | } |
2289 | ||
fa289bec | 2290 | /* |
cdd6c482 | 2291 | * Put a event into inactive state and update time fields. |
fa289bec PM |
2292 | * Enabling the leader of a group effectively enables all |
2293 | * the group members that aren't explicitly disabled, so we | |
2294 | * have to update their ->tstamp_enabled also. | |
2295 | * Note: this works for group members as well as group leaders | |
2296 | * since the non-leader members' sibling_lists will be empty. | |
2297 | */ | |
1d9b482e | 2298 | static void __perf_event_mark_enabled(struct perf_event *event) |
fa289bec | 2299 | { |
cdd6c482 | 2300 | struct perf_event *sub; |
4158755d | 2301 | u64 tstamp = perf_event_time(event); |
fa289bec | 2302 | |
cdd6c482 | 2303 | event->state = PERF_EVENT_STATE_INACTIVE; |
4158755d | 2304 | event->tstamp_enabled = tstamp - event->total_time_enabled; |
9ed6060d | 2305 | list_for_each_entry(sub, &event->sibling_list, group_entry) { |
4158755d SE |
2306 | if (sub->state >= PERF_EVENT_STATE_INACTIVE) |
2307 | sub->tstamp_enabled = tstamp - sub->total_time_enabled; | |
9ed6060d | 2308 | } |
fa289bec PM |
2309 | } |
2310 | ||
d859e29f | 2311 | /* |
cdd6c482 | 2312 | * Cross CPU call to enable a performance event |
d859e29f | 2313 | */ |
fae3fde6 PZ |
2314 | static void __perf_event_enable(struct perf_event *event, |
2315 | struct perf_cpu_context *cpuctx, | |
2316 | struct perf_event_context *ctx, | |
2317 | void *info) | |
04289bb9 | 2318 | { |
cdd6c482 | 2319 | struct perf_event *leader = event->group_leader; |
fae3fde6 | 2320 | struct perf_event_context *task_ctx; |
04289bb9 | 2321 | |
6e801e01 PZ |
2322 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2323 | event->state <= PERF_EVENT_STATE_ERROR) | |
fae3fde6 | 2324 | return; |
3cbed429 | 2325 | |
bd2afa49 PZ |
2326 | if (ctx->is_active) |
2327 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); | |
2328 | ||
1d9b482e | 2329 | __perf_event_mark_enabled(event); |
04289bb9 | 2330 | |
fae3fde6 PZ |
2331 | if (!ctx->is_active) |
2332 | return; | |
2333 | ||
e5d1367f | 2334 | if (!event_filter_match(event)) { |
bd2afa49 | 2335 | if (is_cgroup_event(event)) |
e5d1367f | 2336 | perf_cgroup_defer_enabled(event); |
bd2afa49 | 2337 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); |
fae3fde6 | 2338 | return; |
e5d1367f | 2339 | } |
f4c4176f | 2340 | |
04289bb9 | 2341 | /* |
cdd6c482 | 2342 | * If the event is in a group and isn't the group leader, |
d859e29f | 2343 | * then don't put it on unless the group is on. |
04289bb9 | 2344 | */ |
bd2afa49 PZ |
2345 | if (leader != event && leader->state != PERF_EVENT_STATE_ACTIVE) { |
2346 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
fae3fde6 | 2347 | return; |
bd2afa49 | 2348 | } |
fe4b04fa | 2349 | |
fae3fde6 PZ |
2350 | task_ctx = cpuctx->task_ctx; |
2351 | if (ctx->task) | |
2352 | WARN_ON_ONCE(task_ctx != ctx); | |
d859e29f | 2353 | |
fae3fde6 | 2354 | ctx_resched(cpuctx, task_ctx); |
7b648018 PZ |
2355 | } |
2356 | ||
d859e29f | 2357 | /* |
cdd6c482 | 2358 | * Enable a event. |
c93f7669 | 2359 | * |
cdd6c482 IM |
2360 | * If event->ctx is a cloned context, callers must make sure that |
2361 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 2362 | * remains valid. This condition is satisfied when called through |
cdd6c482 IM |
2363 | * perf_event_for_each_child or perf_event_for_each as described |
2364 | * for perf_event_disable. | |
d859e29f | 2365 | */ |
f63a8daa | 2366 | static void _perf_event_enable(struct perf_event *event) |
d859e29f | 2367 | { |
cdd6c482 | 2368 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 2369 | |
7b648018 | 2370 | raw_spin_lock_irq(&ctx->lock); |
6e801e01 PZ |
2371 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2372 | event->state < PERF_EVENT_STATE_ERROR) { | |
7b648018 | 2373 | raw_spin_unlock_irq(&ctx->lock); |
d859e29f PM |
2374 | return; |
2375 | } | |
2376 | ||
d859e29f | 2377 | /* |
cdd6c482 | 2378 | * If the event is in error state, clear that first. |
7b648018 PZ |
2379 | * |
2380 | * That way, if we see the event in error state below, we know that it | |
2381 | * has gone back into error state, as distinct from the task having | |
2382 | * been scheduled away before the cross-call arrived. | |
d859e29f | 2383 | */ |
cdd6c482 IM |
2384 | if (event->state == PERF_EVENT_STATE_ERROR) |
2385 | event->state = PERF_EVENT_STATE_OFF; | |
e625cce1 | 2386 | raw_spin_unlock_irq(&ctx->lock); |
fe4b04fa | 2387 | |
fae3fde6 | 2388 | event_function_call(event, __perf_event_enable, NULL); |
d859e29f | 2389 | } |
f63a8daa PZ |
2390 | |
2391 | /* | |
2392 | * See perf_event_disable(); | |
2393 | */ | |
2394 | void perf_event_enable(struct perf_event *event) | |
2395 | { | |
2396 | struct perf_event_context *ctx; | |
2397 | ||
2398 | ctx = perf_event_ctx_lock(event); | |
2399 | _perf_event_enable(event); | |
2400 | perf_event_ctx_unlock(event, ctx); | |
2401 | } | |
dcfce4a0 | 2402 | EXPORT_SYMBOL_GPL(perf_event_enable); |
d859e29f | 2403 | |
375637bc AS |
2404 | struct stop_event_data { |
2405 | struct perf_event *event; | |
2406 | unsigned int restart; | |
2407 | }; | |
2408 | ||
95ff4ca2 AS |
2409 | static int __perf_event_stop(void *info) |
2410 | { | |
375637bc AS |
2411 | struct stop_event_data *sd = info; |
2412 | struct perf_event *event = sd->event; | |
95ff4ca2 | 2413 | |
375637bc | 2414 | /* if it's already INACTIVE, do nothing */ |
95ff4ca2 AS |
2415 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) |
2416 | return 0; | |
2417 | ||
2418 | /* matches smp_wmb() in event_sched_in() */ | |
2419 | smp_rmb(); | |
2420 | ||
2421 | /* | |
2422 | * There is a window with interrupts enabled before we get here, | |
2423 | * so we need to check again lest we try to stop another CPU's event. | |
2424 | */ | |
2425 | if (READ_ONCE(event->oncpu) != smp_processor_id()) | |
2426 | return -EAGAIN; | |
2427 | ||
2428 | event->pmu->stop(event, PERF_EF_UPDATE); | |
2429 | ||
375637bc AS |
2430 | /* |
2431 | * May race with the actual stop (through perf_pmu_output_stop()), | |
2432 | * but it is only used for events with AUX ring buffer, and such | |
2433 | * events will refuse to restart because of rb::aux_mmap_count==0, | |
2434 | * see comments in perf_aux_output_begin(). | |
2435 | * | |
2436 | * Since this is happening on a event-local CPU, no trace is lost | |
2437 | * while restarting. | |
2438 | */ | |
2439 | if (sd->restart) | |
2440 | event->pmu->start(event, PERF_EF_START); | |
2441 | ||
95ff4ca2 AS |
2442 | return 0; |
2443 | } | |
2444 | ||
375637bc AS |
2445 | static int perf_event_restart(struct perf_event *event) |
2446 | { | |
2447 | struct stop_event_data sd = { | |
2448 | .event = event, | |
2449 | .restart = 1, | |
2450 | }; | |
2451 | int ret = 0; | |
2452 | ||
2453 | do { | |
2454 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) | |
2455 | return 0; | |
2456 | ||
2457 | /* matches smp_wmb() in event_sched_in() */ | |
2458 | smp_rmb(); | |
2459 | ||
2460 | /* | |
2461 | * We only want to restart ACTIVE events, so if the event goes | |
2462 | * inactive here (event->oncpu==-1), there's nothing more to do; | |
2463 | * fall through with ret==-ENXIO. | |
2464 | */ | |
2465 | ret = cpu_function_call(READ_ONCE(event->oncpu), | |
2466 | __perf_event_stop, &sd); | |
2467 | } while (ret == -EAGAIN); | |
2468 | ||
2469 | return ret; | |
2470 | } | |
2471 | ||
2472 | /* | |
2473 | * In order to contain the amount of racy and tricky in the address filter | |
2474 | * configuration management, it is a two part process: | |
2475 | * | |
2476 | * (p1) when userspace mappings change as a result of (1) or (2) or (3) below, | |
2477 | * we update the addresses of corresponding vmas in | |
2478 | * event::addr_filters_offs array and bump the event::addr_filters_gen; | |
2479 | * (p2) when an event is scheduled in (pmu::add), it calls | |
2480 | * perf_event_addr_filters_sync() which calls pmu::addr_filters_sync() | |
2481 | * if the generation has changed since the previous call. | |
2482 | * | |
2483 | * If (p1) happens while the event is active, we restart it to force (p2). | |
2484 | * | |
2485 | * (1) perf_addr_filters_apply(): adjusting filters' offsets based on | |
2486 | * pre-existing mappings, called once when new filters arrive via SET_FILTER | |
2487 | * ioctl; | |
2488 | * (2) perf_addr_filters_adjust(): adjusting filters' offsets based on newly | |
2489 | * registered mapping, called for every new mmap(), with mm::mmap_sem down | |
2490 | * for reading; | |
2491 | * (3) perf_event_addr_filters_exec(): clearing filters' offsets in the process | |
2492 | * of exec. | |
2493 | */ | |
2494 | void perf_event_addr_filters_sync(struct perf_event *event) | |
2495 | { | |
2496 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
2497 | ||
2498 | if (!has_addr_filter(event)) | |
2499 | return; | |
2500 | ||
2501 | raw_spin_lock(&ifh->lock); | |
2502 | if (event->addr_filters_gen != event->hw.addr_filters_gen) { | |
2503 | event->pmu->addr_filters_sync(event); | |
2504 | event->hw.addr_filters_gen = event->addr_filters_gen; | |
2505 | } | |
2506 | raw_spin_unlock(&ifh->lock); | |
2507 | } | |
2508 | EXPORT_SYMBOL_GPL(perf_event_addr_filters_sync); | |
2509 | ||
f63a8daa | 2510 | static int _perf_event_refresh(struct perf_event *event, int refresh) |
79f14641 | 2511 | { |
2023b359 | 2512 | /* |
cdd6c482 | 2513 | * not supported on inherited events |
2023b359 | 2514 | */ |
2e939d1d | 2515 | if (event->attr.inherit || !is_sampling_event(event)) |
2023b359 PZ |
2516 | return -EINVAL; |
2517 | ||
cdd6c482 | 2518 | atomic_add(refresh, &event->event_limit); |
f63a8daa | 2519 | _perf_event_enable(event); |
2023b359 PZ |
2520 | |
2521 | return 0; | |
79f14641 | 2522 | } |
f63a8daa PZ |
2523 | |
2524 | /* | |
2525 | * See perf_event_disable() | |
2526 | */ | |
2527 | int perf_event_refresh(struct perf_event *event, int refresh) | |
2528 | { | |
2529 | struct perf_event_context *ctx; | |
2530 | int ret; | |
2531 | ||
2532 | ctx = perf_event_ctx_lock(event); | |
2533 | ret = _perf_event_refresh(event, refresh); | |
2534 | perf_event_ctx_unlock(event, ctx); | |
2535 | ||
2536 | return ret; | |
2537 | } | |
26ca5c11 | 2538 | EXPORT_SYMBOL_GPL(perf_event_refresh); |
79f14641 | 2539 | |
5b0311e1 FW |
2540 | static void ctx_sched_out(struct perf_event_context *ctx, |
2541 | struct perf_cpu_context *cpuctx, | |
2542 | enum event_type_t event_type) | |
235c7fc7 | 2543 | { |
db24d33e | 2544 | int is_active = ctx->is_active; |
c994d613 | 2545 | struct perf_event *event; |
235c7fc7 | 2546 | |
c994d613 | 2547 | lockdep_assert_held(&ctx->lock); |
235c7fc7 | 2548 | |
39a43640 PZ |
2549 | if (likely(!ctx->nr_events)) { |
2550 | /* | |
2551 | * See __perf_remove_from_context(). | |
2552 | */ | |
2553 | WARN_ON_ONCE(ctx->is_active); | |
2554 | if (ctx->task) | |
2555 | WARN_ON_ONCE(cpuctx->task_ctx); | |
facc4307 | 2556 | return; |
39a43640 PZ |
2557 | } |
2558 | ||
db24d33e | 2559 | ctx->is_active &= ~event_type; |
3cbaa590 PZ |
2560 | if (!(ctx->is_active & EVENT_ALL)) |
2561 | ctx->is_active = 0; | |
2562 | ||
63e30d3e PZ |
2563 | if (ctx->task) { |
2564 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
2565 | if (!ctx->is_active) | |
2566 | cpuctx->task_ctx = NULL; | |
2567 | } | |
facc4307 | 2568 | |
8fdc6539 PZ |
2569 | /* |
2570 | * Always update time if it was set; not only when it changes. | |
2571 | * Otherwise we can 'forget' to update time for any but the last | |
2572 | * context we sched out. For example: | |
2573 | * | |
2574 | * ctx_sched_out(.event_type = EVENT_FLEXIBLE) | |
2575 | * ctx_sched_out(.event_type = EVENT_PINNED) | |
2576 | * | |
2577 | * would only update time for the pinned events. | |
2578 | */ | |
3cbaa590 PZ |
2579 | if (is_active & EVENT_TIME) { |
2580 | /* update (and stop) ctx time */ | |
2581 | update_context_time(ctx); | |
2582 | update_cgrp_time_from_cpuctx(cpuctx); | |
2583 | } | |
2584 | ||
8fdc6539 PZ |
2585 | is_active ^= ctx->is_active; /* changed bits */ |
2586 | ||
3cbaa590 | 2587 | if (!ctx->nr_active || !(is_active & EVENT_ALL)) |
facc4307 | 2588 | return; |
5b0311e1 | 2589 | |
075e0b00 | 2590 | perf_pmu_disable(ctx->pmu); |
3cbaa590 | 2591 | if (is_active & EVENT_PINNED) { |
889ff015 FW |
2592 | list_for_each_entry(event, &ctx->pinned_groups, group_entry) |
2593 | group_sched_out(event, cpuctx, ctx); | |
9ed6060d | 2594 | } |
889ff015 | 2595 | |
3cbaa590 | 2596 | if (is_active & EVENT_FLEXIBLE) { |
889ff015 | 2597 | list_for_each_entry(event, &ctx->flexible_groups, group_entry) |
8c9ed8e1 | 2598 | group_sched_out(event, cpuctx, ctx); |
9ed6060d | 2599 | } |
1b9a644f | 2600 | perf_pmu_enable(ctx->pmu); |
235c7fc7 IM |
2601 | } |
2602 | ||
564c2b21 | 2603 | /* |
5a3126d4 PZ |
2604 | * Test whether two contexts are equivalent, i.e. whether they have both been |
2605 | * cloned from the same version of the same context. | |
2606 | * | |
2607 | * Equivalence is measured using a generation number in the context that is | |
2608 | * incremented on each modification to it; see unclone_ctx(), list_add_event() | |
2609 | * and list_del_event(). | |
564c2b21 | 2610 | */ |
cdd6c482 IM |
2611 | static int context_equiv(struct perf_event_context *ctx1, |
2612 | struct perf_event_context *ctx2) | |
564c2b21 | 2613 | { |
211de6eb PZ |
2614 | lockdep_assert_held(&ctx1->lock); |
2615 | lockdep_assert_held(&ctx2->lock); | |
2616 | ||
5a3126d4 PZ |
2617 | /* Pinning disables the swap optimization */ |
2618 | if (ctx1->pin_count || ctx2->pin_count) | |
2619 | return 0; | |
2620 | ||
2621 | /* If ctx1 is the parent of ctx2 */ | |
2622 | if (ctx1 == ctx2->parent_ctx && ctx1->generation == ctx2->parent_gen) | |
2623 | return 1; | |
2624 | ||
2625 | /* If ctx2 is the parent of ctx1 */ | |
2626 | if (ctx1->parent_ctx == ctx2 && ctx1->parent_gen == ctx2->generation) | |
2627 | return 1; | |
2628 | ||
2629 | /* | |
2630 | * If ctx1 and ctx2 have the same parent; we flatten the parent | |
2631 | * hierarchy, see perf_event_init_context(). | |
2632 | */ | |
2633 | if (ctx1->parent_ctx && ctx1->parent_ctx == ctx2->parent_ctx && | |
2634 | ctx1->parent_gen == ctx2->parent_gen) | |
2635 | return 1; | |
2636 | ||
2637 | /* Unmatched */ | |
2638 | return 0; | |
564c2b21 PM |
2639 | } |
2640 | ||
cdd6c482 IM |
2641 | static void __perf_event_sync_stat(struct perf_event *event, |
2642 | struct perf_event *next_event) | |
bfbd3381 PZ |
2643 | { |
2644 | u64 value; | |
2645 | ||
cdd6c482 | 2646 | if (!event->attr.inherit_stat) |
bfbd3381 PZ |
2647 | return; |
2648 | ||
2649 | /* | |
cdd6c482 | 2650 | * Update the event value, we cannot use perf_event_read() |
bfbd3381 PZ |
2651 | * because we're in the middle of a context switch and have IRQs |
2652 | * disabled, which upsets smp_call_function_single(), however | |
cdd6c482 | 2653 | * we know the event must be on the current CPU, therefore we |
bfbd3381 PZ |
2654 | * don't need to use it. |
2655 | */ | |
cdd6c482 IM |
2656 | switch (event->state) { |
2657 | case PERF_EVENT_STATE_ACTIVE: | |
3dbebf15 PZ |
2658 | event->pmu->read(event); |
2659 | /* fall-through */ | |
bfbd3381 | 2660 | |
cdd6c482 IM |
2661 | case PERF_EVENT_STATE_INACTIVE: |
2662 | update_event_times(event); | |
bfbd3381 PZ |
2663 | break; |
2664 | ||
2665 | default: | |
2666 | break; | |
2667 | } | |
2668 | ||
2669 | /* | |
cdd6c482 | 2670 | * In order to keep per-task stats reliable we need to flip the event |
bfbd3381 PZ |
2671 | * values when we flip the contexts. |
2672 | */ | |
e7850595 PZ |
2673 | value = local64_read(&next_event->count); |
2674 | value = local64_xchg(&event->count, value); | |
2675 | local64_set(&next_event->count, value); | |
bfbd3381 | 2676 | |
cdd6c482 IM |
2677 | swap(event->total_time_enabled, next_event->total_time_enabled); |
2678 | swap(event->total_time_running, next_event->total_time_running); | |
19d2e755 | 2679 | |
bfbd3381 | 2680 | /* |
19d2e755 | 2681 | * Since we swizzled the values, update the user visible data too. |
bfbd3381 | 2682 | */ |
cdd6c482 IM |
2683 | perf_event_update_userpage(event); |
2684 | perf_event_update_userpage(next_event); | |
bfbd3381 PZ |
2685 | } |
2686 | ||
cdd6c482 IM |
2687 | static void perf_event_sync_stat(struct perf_event_context *ctx, |
2688 | struct perf_event_context *next_ctx) | |
bfbd3381 | 2689 | { |
cdd6c482 | 2690 | struct perf_event *event, *next_event; |
bfbd3381 PZ |
2691 | |
2692 | if (!ctx->nr_stat) | |
2693 | return; | |
2694 | ||
02ffdbc8 PZ |
2695 | update_context_time(ctx); |
2696 | ||
cdd6c482 IM |
2697 | event = list_first_entry(&ctx->event_list, |
2698 | struct perf_event, event_entry); | |
bfbd3381 | 2699 | |
cdd6c482 IM |
2700 | next_event = list_first_entry(&next_ctx->event_list, |
2701 | struct perf_event, event_entry); | |
bfbd3381 | 2702 | |
cdd6c482 IM |
2703 | while (&event->event_entry != &ctx->event_list && |
2704 | &next_event->event_entry != &next_ctx->event_list) { | |
bfbd3381 | 2705 | |
cdd6c482 | 2706 | __perf_event_sync_stat(event, next_event); |
bfbd3381 | 2707 | |
cdd6c482 IM |
2708 | event = list_next_entry(event, event_entry); |
2709 | next_event = list_next_entry(next_event, event_entry); | |
bfbd3381 PZ |
2710 | } |
2711 | } | |
2712 | ||
fe4b04fa PZ |
2713 | static void perf_event_context_sched_out(struct task_struct *task, int ctxn, |
2714 | struct task_struct *next) | |
0793a61d | 2715 | { |
8dc85d54 | 2716 | struct perf_event_context *ctx = task->perf_event_ctxp[ctxn]; |
cdd6c482 | 2717 | struct perf_event_context *next_ctx; |
5a3126d4 | 2718 | struct perf_event_context *parent, *next_parent; |
108b02cf | 2719 | struct perf_cpu_context *cpuctx; |
c93f7669 | 2720 | int do_switch = 1; |
0793a61d | 2721 | |
108b02cf PZ |
2722 | if (likely(!ctx)) |
2723 | return; | |
10989fb2 | 2724 | |
108b02cf PZ |
2725 | cpuctx = __get_cpu_context(ctx); |
2726 | if (!cpuctx->task_ctx) | |
0793a61d TG |
2727 | return; |
2728 | ||
c93f7669 | 2729 | rcu_read_lock(); |
8dc85d54 | 2730 | next_ctx = next->perf_event_ctxp[ctxn]; |
5a3126d4 PZ |
2731 | if (!next_ctx) |
2732 | goto unlock; | |
2733 | ||
2734 | parent = rcu_dereference(ctx->parent_ctx); | |
2735 | next_parent = rcu_dereference(next_ctx->parent_ctx); | |
2736 | ||
2737 | /* If neither context have a parent context; they cannot be clones. */ | |
802c8a61 | 2738 | if (!parent && !next_parent) |
5a3126d4 PZ |
2739 | goto unlock; |
2740 | ||
2741 | if (next_parent == ctx || next_ctx == parent || next_parent == parent) { | |
c93f7669 PM |
2742 | /* |
2743 | * Looks like the two contexts are clones, so we might be | |
2744 | * able to optimize the context switch. We lock both | |
2745 | * contexts and check that they are clones under the | |
2746 | * lock (including re-checking that neither has been | |
2747 | * uncloned in the meantime). It doesn't matter which | |
2748 | * order we take the locks because no other cpu could | |
2749 | * be trying to lock both of these tasks. | |
2750 | */ | |
e625cce1 TG |
2751 | raw_spin_lock(&ctx->lock); |
2752 | raw_spin_lock_nested(&next_ctx->lock, SINGLE_DEPTH_NESTING); | |
c93f7669 | 2753 | if (context_equiv(ctx, next_ctx)) { |
63b6da39 PZ |
2754 | WRITE_ONCE(ctx->task, next); |
2755 | WRITE_ONCE(next_ctx->task, task); | |
5a158c3c YZ |
2756 | |
2757 | swap(ctx->task_ctx_data, next_ctx->task_ctx_data); | |
2758 | ||
63b6da39 PZ |
2759 | /* |
2760 | * RCU_INIT_POINTER here is safe because we've not | |
2761 | * modified the ctx and the above modification of | |
2762 | * ctx->task and ctx->task_ctx_data are immaterial | |
2763 | * since those values are always verified under | |
2764 | * ctx->lock which we're now holding. | |
2765 | */ | |
2766 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], next_ctx); | |
2767 | RCU_INIT_POINTER(next->perf_event_ctxp[ctxn], ctx); | |
2768 | ||
c93f7669 | 2769 | do_switch = 0; |
bfbd3381 | 2770 | |
cdd6c482 | 2771 | perf_event_sync_stat(ctx, next_ctx); |
c93f7669 | 2772 | } |
e625cce1 TG |
2773 | raw_spin_unlock(&next_ctx->lock); |
2774 | raw_spin_unlock(&ctx->lock); | |
564c2b21 | 2775 | } |
5a3126d4 | 2776 | unlock: |
c93f7669 | 2777 | rcu_read_unlock(); |
564c2b21 | 2778 | |
c93f7669 | 2779 | if (do_switch) { |
facc4307 | 2780 | raw_spin_lock(&ctx->lock); |
8833d0e2 | 2781 | task_ctx_sched_out(cpuctx, ctx); |
facc4307 | 2782 | raw_spin_unlock(&ctx->lock); |
c93f7669 | 2783 | } |
0793a61d TG |
2784 | } |
2785 | ||
ba532500 YZ |
2786 | void perf_sched_cb_dec(struct pmu *pmu) |
2787 | { | |
2788 | this_cpu_dec(perf_sched_cb_usages); | |
2789 | } | |
2790 | ||
2791 | void perf_sched_cb_inc(struct pmu *pmu) | |
2792 | { | |
2793 | this_cpu_inc(perf_sched_cb_usages); | |
2794 | } | |
2795 | ||
2796 | /* | |
2797 | * This function provides the context switch callback to the lower code | |
2798 | * layer. It is invoked ONLY when the context switch callback is enabled. | |
2799 | */ | |
2800 | static void perf_pmu_sched_task(struct task_struct *prev, | |
2801 | struct task_struct *next, | |
2802 | bool sched_in) | |
2803 | { | |
2804 | struct perf_cpu_context *cpuctx; | |
2805 | struct pmu *pmu; | |
2806 | unsigned long flags; | |
2807 | ||
2808 | if (prev == next) | |
2809 | return; | |
2810 | ||
2811 | local_irq_save(flags); | |
2812 | ||
2813 | rcu_read_lock(); | |
2814 | ||
2815 | list_for_each_entry_rcu(pmu, &pmus, entry) { | |
2816 | if (pmu->sched_task) { | |
2817 | cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); | |
2818 | ||
2819 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); | |
2820 | ||
2821 | perf_pmu_disable(pmu); | |
2822 | ||
2823 | pmu->sched_task(cpuctx->task_ctx, sched_in); | |
2824 | ||
2825 | perf_pmu_enable(pmu); | |
2826 | ||
2827 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
2828 | } | |
2829 | } | |
2830 | ||
2831 | rcu_read_unlock(); | |
2832 | ||
2833 | local_irq_restore(flags); | |
2834 | } | |
2835 | ||
45ac1403 AH |
2836 | static void perf_event_switch(struct task_struct *task, |
2837 | struct task_struct *next_prev, bool sched_in); | |
2838 | ||
8dc85d54 PZ |
2839 | #define for_each_task_context_nr(ctxn) \ |
2840 | for ((ctxn) = 0; (ctxn) < perf_nr_task_contexts; (ctxn)++) | |
2841 | ||
2842 | /* | |
2843 | * Called from scheduler to remove the events of the current task, | |
2844 | * with interrupts disabled. | |
2845 | * | |
2846 | * We stop each event and update the event value in event->count. | |
2847 | * | |
2848 | * This does not protect us against NMI, but disable() | |
2849 | * sets the disabled bit in the control field of event _before_ | |
2850 | * accessing the event control register. If a NMI hits, then it will | |
2851 | * not restart the event. | |
2852 | */ | |
ab0cce56 JO |
2853 | void __perf_event_task_sched_out(struct task_struct *task, |
2854 | struct task_struct *next) | |
8dc85d54 PZ |
2855 | { |
2856 | int ctxn; | |
2857 | ||
ba532500 YZ |
2858 | if (__this_cpu_read(perf_sched_cb_usages)) |
2859 | perf_pmu_sched_task(task, next, false); | |
2860 | ||
45ac1403 AH |
2861 | if (atomic_read(&nr_switch_events)) |
2862 | perf_event_switch(task, next, false); | |
2863 | ||
8dc85d54 PZ |
2864 | for_each_task_context_nr(ctxn) |
2865 | perf_event_context_sched_out(task, ctxn, next); | |
e5d1367f SE |
2866 | |
2867 | /* | |
2868 | * if cgroup events exist on this CPU, then we need | |
2869 | * to check if we have to switch out PMU state. | |
2870 | * cgroup event are system-wide mode only | |
2871 | */ | |
4a32fea9 | 2872 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) |
a8d757ef | 2873 | perf_cgroup_sched_out(task, next); |
8dc85d54 PZ |
2874 | } |
2875 | ||
5b0311e1 FW |
2876 | /* |
2877 | * Called with IRQs disabled | |
2878 | */ | |
2879 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, | |
2880 | enum event_type_t event_type) | |
2881 | { | |
2882 | ctx_sched_out(&cpuctx->ctx, cpuctx, event_type); | |
04289bb9 IM |
2883 | } |
2884 | ||
235c7fc7 | 2885 | static void |
5b0311e1 | 2886 | ctx_pinned_sched_in(struct perf_event_context *ctx, |
6e37738a | 2887 | struct perf_cpu_context *cpuctx) |
0793a61d | 2888 | { |
cdd6c482 | 2889 | struct perf_event *event; |
0793a61d | 2890 | |
889ff015 FW |
2891 | list_for_each_entry(event, &ctx->pinned_groups, group_entry) { |
2892 | if (event->state <= PERF_EVENT_STATE_OFF) | |
3b6f9e5c | 2893 | continue; |
5632ab12 | 2894 | if (!event_filter_match(event)) |
3b6f9e5c PM |
2895 | continue; |
2896 | ||
e5d1367f SE |
2897 | /* may need to reset tstamp_enabled */ |
2898 | if (is_cgroup_event(event)) | |
2899 | perf_cgroup_mark_enabled(event, ctx); | |
2900 | ||
8c9ed8e1 | 2901 | if (group_can_go_on(event, cpuctx, 1)) |
6e37738a | 2902 | group_sched_in(event, cpuctx, ctx); |
3b6f9e5c PM |
2903 | |
2904 | /* | |
2905 | * If this pinned group hasn't been scheduled, | |
2906 | * put it in error state. | |
2907 | */ | |
cdd6c482 IM |
2908 | if (event->state == PERF_EVENT_STATE_INACTIVE) { |
2909 | update_group_times(event); | |
2910 | event->state = PERF_EVENT_STATE_ERROR; | |
53cfbf59 | 2911 | } |
3b6f9e5c | 2912 | } |
5b0311e1 FW |
2913 | } |
2914 | ||
2915 | static void | |
2916 | ctx_flexible_sched_in(struct perf_event_context *ctx, | |
6e37738a | 2917 | struct perf_cpu_context *cpuctx) |
5b0311e1 FW |
2918 | { |
2919 | struct perf_event *event; | |
2920 | int can_add_hw = 1; | |
3b6f9e5c | 2921 | |
889ff015 FW |
2922 | list_for_each_entry(event, &ctx->flexible_groups, group_entry) { |
2923 | /* Ignore events in OFF or ERROR state */ | |
2924 | if (event->state <= PERF_EVENT_STATE_OFF) | |
3b6f9e5c | 2925 | continue; |
04289bb9 IM |
2926 | /* |
2927 | * Listen to the 'cpu' scheduling filter constraint | |
cdd6c482 | 2928 | * of events: |
04289bb9 | 2929 | */ |
5632ab12 | 2930 | if (!event_filter_match(event)) |
0793a61d TG |
2931 | continue; |
2932 | ||
e5d1367f SE |
2933 | /* may need to reset tstamp_enabled */ |
2934 | if (is_cgroup_event(event)) | |
2935 | perf_cgroup_mark_enabled(event, ctx); | |
2936 | ||
9ed6060d | 2937 | if (group_can_go_on(event, cpuctx, can_add_hw)) { |
6e37738a | 2938 | if (group_sched_in(event, cpuctx, ctx)) |
dd0e6ba2 | 2939 | can_add_hw = 0; |
9ed6060d | 2940 | } |
0793a61d | 2941 | } |
5b0311e1 FW |
2942 | } |
2943 | ||
2944 | static void | |
2945 | ctx_sched_in(struct perf_event_context *ctx, | |
2946 | struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
2947 | enum event_type_t event_type, |
2948 | struct task_struct *task) | |
5b0311e1 | 2949 | { |
db24d33e | 2950 | int is_active = ctx->is_active; |
c994d613 PZ |
2951 | u64 now; |
2952 | ||
2953 | lockdep_assert_held(&ctx->lock); | |
e5d1367f | 2954 | |
5b0311e1 | 2955 | if (likely(!ctx->nr_events)) |
facc4307 | 2956 | return; |
5b0311e1 | 2957 | |
3cbaa590 | 2958 | ctx->is_active |= (event_type | EVENT_TIME); |
63e30d3e PZ |
2959 | if (ctx->task) { |
2960 | if (!is_active) | |
2961 | cpuctx->task_ctx = ctx; | |
2962 | else | |
2963 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
2964 | } | |
2965 | ||
3cbaa590 PZ |
2966 | is_active ^= ctx->is_active; /* changed bits */ |
2967 | ||
2968 | if (is_active & EVENT_TIME) { | |
2969 | /* start ctx time */ | |
2970 | now = perf_clock(); | |
2971 | ctx->timestamp = now; | |
2972 | perf_cgroup_set_timestamp(task, ctx); | |
2973 | } | |
2974 | ||
5b0311e1 FW |
2975 | /* |
2976 | * First go through the list and put on any pinned groups | |
2977 | * in order to give them the best chance of going on. | |
2978 | */ | |
3cbaa590 | 2979 | if (is_active & EVENT_PINNED) |
6e37738a | 2980 | ctx_pinned_sched_in(ctx, cpuctx); |
5b0311e1 FW |
2981 | |
2982 | /* Then walk through the lower prio flexible groups */ | |
3cbaa590 | 2983 | if (is_active & EVENT_FLEXIBLE) |
6e37738a | 2984 | ctx_flexible_sched_in(ctx, cpuctx); |
235c7fc7 IM |
2985 | } |
2986 | ||
329c0e01 | 2987 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, |
e5d1367f SE |
2988 | enum event_type_t event_type, |
2989 | struct task_struct *task) | |
329c0e01 FW |
2990 | { |
2991 | struct perf_event_context *ctx = &cpuctx->ctx; | |
2992 | ||
e5d1367f | 2993 | ctx_sched_in(ctx, cpuctx, event_type, task); |
329c0e01 FW |
2994 | } |
2995 | ||
e5d1367f SE |
2996 | static void perf_event_context_sched_in(struct perf_event_context *ctx, |
2997 | struct task_struct *task) | |
235c7fc7 | 2998 | { |
108b02cf | 2999 | struct perf_cpu_context *cpuctx; |
235c7fc7 | 3000 | |
108b02cf | 3001 | cpuctx = __get_cpu_context(ctx); |
329c0e01 FW |
3002 | if (cpuctx->task_ctx == ctx) |
3003 | return; | |
3004 | ||
facc4307 | 3005 | perf_ctx_lock(cpuctx, ctx); |
1b9a644f | 3006 | perf_pmu_disable(ctx->pmu); |
329c0e01 FW |
3007 | /* |
3008 | * We want to keep the following priority order: | |
3009 | * cpu pinned (that don't need to move), task pinned, | |
3010 | * cpu flexible, task flexible. | |
3011 | */ | |
3012 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
63e30d3e | 3013 | perf_event_sched_in(cpuctx, ctx, task); |
facc4307 PZ |
3014 | perf_pmu_enable(ctx->pmu); |
3015 | perf_ctx_unlock(cpuctx, ctx); | |
235c7fc7 IM |
3016 | } |
3017 | ||
8dc85d54 PZ |
3018 | /* |
3019 | * Called from scheduler to add the events of the current task | |
3020 | * with interrupts disabled. | |
3021 | * | |
3022 | * We restore the event value and then enable it. | |
3023 | * | |
3024 | * This does not protect us against NMI, but enable() | |
3025 | * sets the enabled bit in the control field of event _before_ | |
3026 | * accessing the event control register. If a NMI hits, then it will | |
3027 | * keep the event running. | |
3028 | */ | |
ab0cce56 JO |
3029 | void __perf_event_task_sched_in(struct task_struct *prev, |
3030 | struct task_struct *task) | |
8dc85d54 PZ |
3031 | { |
3032 | struct perf_event_context *ctx; | |
3033 | int ctxn; | |
3034 | ||
7e41d177 PZ |
3035 | /* |
3036 | * If cgroup events exist on this CPU, then we need to check if we have | |
3037 | * to switch in PMU state; cgroup event are system-wide mode only. | |
3038 | * | |
3039 | * Since cgroup events are CPU events, we must schedule these in before | |
3040 | * we schedule in the task events. | |
3041 | */ | |
3042 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) | |
3043 | perf_cgroup_sched_in(prev, task); | |
3044 | ||
8dc85d54 PZ |
3045 | for_each_task_context_nr(ctxn) { |
3046 | ctx = task->perf_event_ctxp[ctxn]; | |
3047 | if (likely(!ctx)) | |
3048 | continue; | |
3049 | ||
e5d1367f | 3050 | perf_event_context_sched_in(ctx, task); |
8dc85d54 | 3051 | } |
d010b332 | 3052 | |
45ac1403 AH |
3053 | if (atomic_read(&nr_switch_events)) |
3054 | perf_event_switch(task, prev, true); | |
3055 | ||
ba532500 YZ |
3056 | if (__this_cpu_read(perf_sched_cb_usages)) |
3057 | perf_pmu_sched_task(prev, task, true); | |
235c7fc7 IM |
3058 | } |
3059 | ||
abd50713 PZ |
3060 | static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count) |
3061 | { | |
3062 | u64 frequency = event->attr.sample_freq; | |
3063 | u64 sec = NSEC_PER_SEC; | |
3064 | u64 divisor, dividend; | |
3065 | ||
3066 | int count_fls, nsec_fls, frequency_fls, sec_fls; | |
3067 | ||
3068 | count_fls = fls64(count); | |
3069 | nsec_fls = fls64(nsec); | |
3070 | frequency_fls = fls64(frequency); | |
3071 | sec_fls = 30; | |
3072 | ||
3073 | /* | |
3074 | * We got @count in @nsec, with a target of sample_freq HZ | |
3075 | * the target period becomes: | |
3076 | * | |
3077 | * @count * 10^9 | |
3078 | * period = ------------------- | |
3079 | * @nsec * sample_freq | |
3080 | * | |
3081 | */ | |
3082 | ||
3083 | /* | |
3084 | * Reduce accuracy by one bit such that @a and @b converge | |
3085 | * to a similar magnitude. | |
3086 | */ | |
fe4b04fa | 3087 | #define REDUCE_FLS(a, b) \ |
abd50713 PZ |
3088 | do { \ |
3089 | if (a##_fls > b##_fls) { \ | |
3090 | a >>= 1; \ | |
3091 | a##_fls--; \ | |
3092 | } else { \ | |
3093 | b >>= 1; \ | |
3094 | b##_fls--; \ | |
3095 | } \ | |
3096 | } while (0) | |
3097 | ||
3098 | /* | |
3099 | * Reduce accuracy until either term fits in a u64, then proceed with | |
3100 | * the other, so that finally we can do a u64/u64 division. | |
3101 | */ | |
3102 | while (count_fls + sec_fls > 64 && nsec_fls + frequency_fls > 64) { | |
3103 | REDUCE_FLS(nsec, frequency); | |
3104 | REDUCE_FLS(sec, count); | |
3105 | } | |
3106 | ||
3107 | if (count_fls + sec_fls > 64) { | |
3108 | divisor = nsec * frequency; | |
3109 | ||
3110 | while (count_fls + sec_fls > 64) { | |
3111 | REDUCE_FLS(count, sec); | |
3112 | divisor >>= 1; | |
3113 | } | |
3114 | ||
3115 | dividend = count * sec; | |
3116 | } else { | |
3117 | dividend = count * sec; | |
3118 | ||
3119 | while (nsec_fls + frequency_fls > 64) { | |
3120 | REDUCE_FLS(nsec, frequency); | |
3121 | dividend >>= 1; | |
3122 | } | |
3123 | ||
3124 | divisor = nsec * frequency; | |
3125 | } | |
3126 | ||
f6ab91ad PZ |
3127 | if (!divisor) |
3128 | return dividend; | |
3129 | ||
abd50713 PZ |
3130 | return div64_u64(dividend, divisor); |
3131 | } | |
3132 | ||
e050e3f0 SE |
3133 | static DEFINE_PER_CPU(int, perf_throttled_count); |
3134 | static DEFINE_PER_CPU(u64, perf_throttled_seq); | |
3135 | ||
f39d47ff | 3136 | static void perf_adjust_period(struct perf_event *event, u64 nsec, u64 count, bool disable) |
bd2b5b12 | 3137 | { |
cdd6c482 | 3138 | struct hw_perf_event *hwc = &event->hw; |
f6ab91ad | 3139 | s64 period, sample_period; |
bd2b5b12 PZ |
3140 | s64 delta; |
3141 | ||
abd50713 | 3142 | period = perf_calculate_period(event, nsec, count); |
bd2b5b12 PZ |
3143 | |
3144 | delta = (s64)(period - hwc->sample_period); | |
3145 | delta = (delta + 7) / 8; /* low pass filter */ | |
3146 | ||
3147 | sample_period = hwc->sample_period + delta; | |
3148 | ||
3149 | if (!sample_period) | |
3150 | sample_period = 1; | |
3151 | ||
bd2b5b12 | 3152 | hwc->sample_period = sample_period; |
abd50713 | 3153 | |
e7850595 | 3154 | if (local64_read(&hwc->period_left) > 8*sample_period) { |
f39d47ff SE |
3155 | if (disable) |
3156 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3157 | ||
e7850595 | 3158 | local64_set(&hwc->period_left, 0); |
f39d47ff SE |
3159 | |
3160 | if (disable) | |
3161 | event->pmu->start(event, PERF_EF_RELOAD); | |
abd50713 | 3162 | } |
bd2b5b12 PZ |
3163 | } |
3164 | ||
e050e3f0 SE |
3165 | /* |
3166 | * combine freq adjustment with unthrottling to avoid two passes over the | |
3167 | * events. At the same time, make sure, having freq events does not change | |
3168 | * the rate of unthrottling as that would introduce bias. | |
3169 | */ | |
3170 | static void perf_adjust_freq_unthr_context(struct perf_event_context *ctx, | |
3171 | int needs_unthr) | |
60db5e09 | 3172 | { |
cdd6c482 IM |
3173 | struct perf_event *event; |
3174 | struct hw_perf_event *hwc; | |
e050e3f0 | 3175 | u64 now, period = TICK_NSEC; |
abd50713 | 3176 | s64 delta; |
60db5e09 | 3177 | |
e050e3f0 SE |
3178 | /* |
3179 | * only need to iterate over all events iff: | |
3180 | * - context have events in frequency mode (needs freq adjust) | |
3181 | * - there are events to unthrottle on this cpu | |
3182 | */ | |
3183 | if (!(ctx->nr_freq || needs_unthr)) | |
0f5a2601 PZ |
3184 | return; |
3185 | ||
e050e3f0 | 3186 | raw_spin_lock(&ctx->lock); |
f39d47ff | 3187 | perf_pmu_disable(ctx->pmu); |
e050e3f0 | 3188 | |
03541f8b | 3189 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { |
cdd6c482 | 3190 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
60db5e09 PZ |
3191 | continue; |
3192 | ||
5632ab12 | 3193 | if (!event_filter_match(event)) |
5d27c23d PZ |
3194 | continue; |
3195 | ||
44377277 AS |
3196 | perf_pmu_disable(event->pmu); |
3197 | ||
cdd6c482 | 3198 | hwc = &event->hw; |
6a24ed6c | 3199 | |
ae23bff1 | 3200 | if (hwc->interrupts == MAX_INTERRUPTS) { |
e050e3f0 | 3201 | hwc->interrupts = 0; |
cdd6c482 | 3202 | perf_log_throttle(event, 1); |
a4eaf7f1 | 3203 | event->pmu->start(event, 0); |
a78ac325 PZ |
3204 | } |
3205 | ||
cdd6c482 | 3206 | if (!event->attr.freq || !event->attr.sample_freq) |
44377277 | 3207 | goto next; |
60db5e09 | 3208 | |
e050e3f0 SE |
3209 | /* |
3210 | * stop the event and update event->count | |
3211 | */ | |
3212 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3213 | ||
e7850595 | 3214 | now = local64_read(&event->count); |
abd50713 PZ |
3215 | delta = now - hwc->freq_count_stamp; |
3216 | hwc->freq_count_stamp = now; | |
60db5e09 | 3217 | |
e050e3f0 SE |
3218 | /* |
3219 | * restart the event | |
3220 | * reload only if value has changed | |
f39d47ff SE |
3221 | * we have stopped the event so tell that |
3222 | * to perf_adjust_period() to avoid stopping it | |
3223 | * twice. | |
e050e3f0 | 3224 | */ |
abd50713 | 3225 | if (delta > 0) |
f39d47ff | 3226 | perf_adjust_period(event, period, delta, false); |
e050e3f0 SE |
3227 | |
3228 | event->pmu->start(event, delta > 0 ? PERF_EF_RELOAD : 0); | |
44377277 AS |
3229 | next: |
3230 | perf_pmu_enable(event->pmu); | |
60db5e09 | 3231 | } |
e050e3f0 | 3232 | |
f39d47ff | 3233 | perf_pmu_enable(ctx->pmu); |
e050e3f0 | 3234 | raw_spin_unlock(&ctx->lock); |
60db5e09 PZ |
3235 | } |
3236 | ||
235c7fc7 | 3237 | /* |
cdd6c482 | 3238 | * Round-robin a context's events: |
235c7fc7 | 3239 | */ |
cdd6c482 | 3240 | static void rotate_ctx(struct perf_event_context *ctx) |
0793a61d | 3241 | { |
dddd3379 TG |
3242 | /* |
3243 | * Rotate the first entry last of non-pinned groups. Rotation might be | |
3244 | * disabled by the inheritance code. | |
3245 | */ | |
3246 | if (!ctx->rotate_disable) | |
3247 | list_rotate_left(&ctx->flexible_groups); | |
235c7fc7 IM |
3248 | } |
3249 | ||
9e630205 | 3250 | static int perf_rotate_context(struct perf_cpu_context *cpuctx) |
235c7fc7 | 3251 | { |
8dc85d54 | 3252 | struct perf_event_context *ctx = NULL; |
2fde4f94 | 3253 | int rotate = 0; |
7fc23a53 | 3254 | |
b5ab4cd5 | 3255 | if (cpuctx->ctx.nr_events) { |
b5ab4cd5 PZ |
3256 | if (cpuctx->ctx.nr_events != cpuctx->ctx.nr_active) |
3257 | rotate = 1; | |
3258 | } | |
235c7fc7 | 3259 | |
8dc85d54 | 3260 | ctx = cpuctx->task_ctx; |
b5ab4cd5 | 3261 | if (ctx && ctx->nr_events) { |
b5ab4cd5 PZ |
3262 | if (ctx->nr_events != ctx->nr_active) |
3263 | rotate = 1; | |
3264 | } | |
9717e6cd | 3265 | |
e050e3f0 | 3266 | if (!rotate) |
0f5a2601 PZ |
3267 | goto done; |
3268 | ||
facc4307 | 3269 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
1b9a644f | 3270 | perf_pmu_disable(cpuctx->ctx.pmu); |
60db5e09 | 3271 | |
e050e3f0 SE |
3272 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); |
3273 | if (ctx) | |
3274 | ctx_sched_out(ctx, cpuctx, EVENT_FLEXIBLE); | |
0793a61d | 3275 | |
e050e3f0 SE |
3276 | rotate_ctx(&cpuctx->ctx); |
3277 | if (ctx) | |
3278 | rotate_ctx(ctx); | |
235c7fc7 | 3279 | |
e050e3f0 | 3280 | perf_event_sched_in(cpuctx, ctx, current); |
235c7fc7 | 3281 | |
0f5a2601 PZ |
3282 | perf_pmu_enable(cpuctx->ctx.pmu); |
3283 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
b5ab4cd5 | 3284 | done: |
9e630205 SE |
3285 | |
3286 | return rotate; | |
e9d2b064 PZ |
3287 | } |
3288 | ||
3289 | void perf_event_task_tick(void) | |
3290 | { | |
2fde4f94 MR |
3291 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
3292 | struct perf_event_context *ctx, *tmp; | |
e050e3f0 | 3293 | int throttled; |
b5ab4cd5 | 3294 | |
e9d2b064 PZ |
3295 | WARN_ON(!irqs_disabled()); |
3296 | ||
e050e3f0 SE |
3297 | __this_cpu_inc(perf_throttled_seq); |
3298 | throttled = __this_cpu_xchg(perf_throttled_count, 0); | |
555e0c1e | 3299 | tick_dep_clear_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
e050e3f0 | 3300 | |
2fde4f94 | 3301 | list_for_each_entry_safe(ctx, tmp, head, active_ctx_list) |
e050e3f0 | 3302 | perf_adjust_freq_unthr_context(ctx, throttled); |
0793a61d TG |
3303 | } |
3304 | ||
889ff015 FW |
3305 | static int event_enable_on_exec(struct perf_event *event, |
3306 | struct perf_event_context *ctx) | |
3307 | { | |
3308 | if (!event->attr.enable_on_exec) | |
3309 | return 0; | |
3310 | ||
3311 | event->attr.enable_on_exec = 0; | |
3312 | if (event->state >= PERF_EVENT_STATE_INACTIVE) | |
3313 | return 0; | |
3314 | ||
1d9b482e | 3315 | __perf_event_mark_enabled(event); |
889ff015 FW |
3316 | |
3317 | return 1; | |
3318 | } | |
3319 | ||
57e7986e | 3320 | /* |
cdd6c482 | 3321 | * Enable all of a task's events that have been marked enable-on-exec. |
57e7986e PM |
3322 | * This expects task == current. |
3323 | */ | |
c1274499 | 3324 | static void perf_event_enable_on_exec(int ctxn) |
57e7986e | 3325 | { |
c1274499 | 3326 | struct perf_event_context *ctx, *clone_ctx = NULL; |
3e349507 | 3327 | struct perf_cpu_context *cpuctx; |
cdd6c482 | 3328 | struct perf_event *event; |
57e7986e PM |
3329 | unsigned long flags; |
3330 | int enabled = 0; | |
3331 | ||
3332 | local_irq_save(flags); | |
c1274499 | 3333 | ctx = current->perf_event_ctxp[ctxn]; |
cdd6c482 | 3334 | if (!ctx || !ctx->nr_events) |
57e7986e PM |
3335 | goto out; |
3336 | ||
3e349507 PZ |
3337 | cpuctx = __get_cpu_context(ctx); |
3338 | perf_ctx_lock(cpuctx, ctx); | |
7fce2509 | 3339 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
3e349507 PZ |
3340 | list_for_each_entry(event, &ctx->event_list, event_entry) |
3341 | enabled |= event_enable_on_exec(event, ctx); | |
57e7986e PM |
3342 | |
3343 | /* | |
3e349507 | 3344 | * Unclone and reschedule this context if we enabled any event. |
57e7986e | 3345 | */ |
3e349507 | 3346 | if (enabled) { |
211de6eb | 3347 | clone_ctx = unclone_ctx(ctx); |
3e349507 PZ |
3348 | ctx_resched(cpuctx, ctx); |
3349 | } | |
3350 | perf_ctx_unlock(cpuctx, ctx); | |
57e7986e | 3351 | |
9ed6060d | 3352 | out: |
57e7986e | 3353 | local_irq_restore(flags); |
211de6eb PZ |
3354 | |
3355 | if (clone_ctx) | |
3356 | put_ctx(clone_ctx); | |
57e7986e PM |
3357 | } |
3358 | ||
0492d4c5 PZ |
3359 | struct perf_read_data { |
3360 | struct perf_event *event; | |
3361 | bool group; | |
7d88962e | 3362 | int ret; |
0492d4c5 PZ |
3363 | }; |
3364 | ||
0793a61d | 3365 | /* |
cdd6c482 | 3366 | * Cross CPU call to read the hardware event |
0793a61d | 3367 | */ |
cdd6c482 | 3368 | static void __perf_event_read(void *info) |
0793a61d | 3369 | { |
0492d4c5 PZ |
3370 | struct perf_read_data *data = info; |
3371 | struct perf_event *sub, *event = data->event; | |
cdd6c482 | 3372 | struct perf_event_context *ctx = event->ctx; |
108b02cf | 3373 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
4a00c16e | 3374 | struct pmu *pmu = event->pmu; |
621a01ea | 3375 | |
e1ac3614 PM |
3376 | /* |
3377 | * If this is a task context, we need to check whether it is | |
3378 | * the current task context of this cpu. If not it has been | |
3379 | * scheduled out before the smp call arrived. In that case | |
cdd6c482 IM |
3380 | * event->count would have been updated to a recent sample |
3381 | * when the event was scheduled out. | |
e1ac3614 PM |
3382 | */ |
3383 | if (ctx->task && cpuctx->task_ctx != ctx) | |
3384 | return; | |
3385 | ||
e625cce1 | 3386 | raw_spin_lock(&ctx->lock); |
e5d1367f | 3387 | if (ctx->is_active) { |
542e72fc | 3388 | update_context_time(ctx); |
e5d1367f SE |
3389 | update_cgrp_time_from_event(event); |
3390 | } | |
0492d4c5 | 3391 | |
cdd6c482 | 3392 | update_event_times(event); |
4a00c16e SB |
3393 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
3394 | goto unlock; | |
0492d4c5 | 3395 | |
4a00c16e SB |
3396 | if (!data->group) { |
3397 | pmu->read(event); | |
3398 | data->ret = 0; | |
0492d4c5 | 3399 | goto unlock; |
4a00c16e SB |
3400 | } |
3401 | ||
3402 | pmu->start_txn(pmu, PERF_PMU_TXN_READ); | |
3403 | ||
3404 | pmu->read(event); | |
0492d4c5 PZ |
3405 | |
3406 | list_for_each_entry(sub, &event->sibling_list, group_entry) { | |
3407 | update_event_times(sub); | |
4a00c16e SB |
3408 | if (sub->state == PERF_EVENT_STATE_ACTIVE) { |
3409 | /* | |
3410 | * Use sibling's PMU rather than @event's since | |
3411 | * sibling could be on different (eg: software) PMU. | |
3412 | */ | |
0492d4c5 | 3413 | sub->pmu->read(sub); |
4a00c16e | 3414 | } |
0492d4c5 | 3415 | } |
4a00c16e SB |
3416 | |
3417 | data->ret = pmu->commit_txn(pmu); | |
0492d4c5 PZ |
3418 | |
3419 | unlock: | |
e625cce1 | 3420 | raw_spin_unlock(&ctx->lock); |
0793a61d TG |
3421 | } |
3422 | ||
b5e58793 PZ |
3423 | static inline u64 perf_event_count(struct perf_event *event) |
3424 | { | |
eacd3ecc MF |
3425 | if (event->pmu->count) |
3426 | return event->pmu->count(event); | |
3427 | ||
3428 | return __perf_event_count(event); | |
b5e58793 PZ |
3429 | } |
3430 | ||
ffe8690c KX |
3431 | /* |
3432 | * NMI-safe method to read a local event, that is an event that | |
3433 | * is: | |
3434 | * - either for the current task, or for this CPU | |
3435 | * - does not have inherit set, for inherited task events | |
3436 | * will not be local and we cannot read them atomically | |
3437 | * - must not have a pmu::count method | |
3438 | */ | |
3439 | u64 perf_event_read_local(struct perf_event *event) | |
3440 | { | |
3441 | unsigned long flags; | |
3442 | u64 val; | |
3443 | ||
3444 | /* | |
3445 | * Disabling interrupts avoids all counter scheduling (context | |
3446 | * switches, timer based rotation and IPIs). | |
3447 | */ | |
3448 | local_irq_save(flags); | |
3449 | ||
3450 | /* If this is a per-task event, it must be for current */ | |
3451 | WARN_ON_ONCE((event->attach_state & PERF_ATTACH_TASK) && | |
3452 | event->hw.target != current); | |
3453 | ||
3454 | /* If this is a per-CPU event, it must be for this CPU */ | |
3455 | WARN_ON_ONCE(!(event->attach_state & PERF_ATTACH_TASK) && | |
3456 | event->cpu != smp_processor_id()); | |
3457 | ||
3458 | /* | |
3459 | * It must not be an event with inherit set, we cannot read | |
3460 | * all child counters from atomic context. | |
3461 | */ | |
3462 | WARN_ON_ONCE(event->attr.inherit); | |
3463 | ||
3464 | /* | |
3465 | * It must not have a pmu::count method, those are not | |
3466 | * NMI safe. | |
3467 | */ | |
3468 | WARN_ON_ONCE(event->pmu->count); | |
3469 | ||
3470 | /* | |
3471 | * If the event is currently on this CPU, its either a per-task event, | |
3472 | * or local to this CPU. Furthermore it means its ACTIVE (otherwise | |
3473 | * oncpu == -1). | |
3474 | */ | |
3475 | if (event->oncpu == smp_processor_id()) | |
3476 | event->pmu->read(event); | |
3477 | ||
3478 | val = local64_read(&event->count); | |
3479 | local_irq_restore(flags); | |
3480 | ||
3481 | return val; | |
3482 | } | |
3483 | ||
7d88962e | 3484 | static int perf_event_read(struct perf_event *event, bool group) |
0793a61d | 3485 | { |
7d88962e SB |
3486 | int ret = 0; |
3487 | ||
0793a61d | 3488 | /* |
cdd6c482 IM |
3489 | * If event is enabled and currently active on a CPU, update the |
3490 | * value in the event structure: | |
0793a61d | 3491 | */ |
cdd6c482 | 3492 | if (event->state == PERF_EVENT_STATE_ACTIVE) { |
0492d4c5 PZ |
3493 | struct perf_read_data data = { |
3494 | .event = event, | |
3495 | .group = group, | |
7d88962e | 3496 | .ret = 0, |
0492d4c5 | 3497 | }; |
cdd6c482 | 3498 | smp_call_function_single(event->oncpu, |
0492d4c5 | 3499 | __perf_event_read, &data, 1); |
7d88962e | 3500 | ret = data.ret; |
cdd6c482 | 3501 | } else if (event->state == PERF_EVENT_STATE_INACTIVE) { |
2b8988c9 PZ |
3502 | struct perf_event_context *ctx = event->ctx; |
3503 | unsigned long flags; | |
3504 | ||
e625cce1 | 3505 | raw_spin_lock_irqsave(&ctx->lock, flags); |
c530ccd9 SE |
3506 | /* |
3507 | * may read while context is not active | |
3508 | * (e.g., thread is blocked), in that case | |
3509 | * we cannot update context time | |
3510 | */ | |
e5d1367f | 3511 | if (ctx->is_active) { |
c530ccd9 | 3512 | update_context_time(ctx); |
e5d1367f SE |
3513 | update_cgrp_time_from_event(event); |
3514 | } | |
0492d4c5 PZ |
3515 | if (group) |
3516 | update_group_times(event); | |
3517 | else | |
3518 | update_event_times(event); | |
e625cce1 | 3519 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
0793a61d | 3520 | } |
7d88962e SB |
3521 | |
3522 | return ret; | |
0793a61d TG |
3523 | } |
3524 | ||
a63eaf34 | 3525 | /* |
cdd6c482 | 3526 | * Initialize the perf_event context in a task_struct: |
a63eaf34 | 3527 | */ |
eb184479 | 3528 | static void __perf_event_init_context(struct perf_event_context *ctx) |
a63eaf34 | 3529 | { |
e625cce1 | 3530 | raw_spin_lock_init(&ctx->lock); |
a63eaf34 | 3531 | mutex_init(&ctx->mutex); |
2fde4f94 | 3532 | INIT_LIST_HEAD(&ctx->active_ctx_list); |
889ff015 FW |
3533 | INIT_LIST_HEAD(&ctx->pinned_groups); |
3534 | INIT_LIST_HEAD(&ctx->flexible_groups); | |
a63eaf34 PM |
3535 | INIT_LIST_HEAD(&ctx->event_list); |
3536 | atomic_set(&ctx->refcount, 1); | |
eb184479 PZ |
3537 | } |
3538 | ||
3539 | static struct perf_event_context * | |
3540 | alloc_perf_context(struct pmu *pmu, struct task_struct *task) | |
3541 | { | |
3542 | struct perf_event_context *ctx; | |
3543 | ||
3544 | ctx = kzalloc(sizeof(struct perf_event_context), GFP_KERNEL); | |
3545 | if (!ctx) | |
3546 | return NULL; | |
3547 | ||
3548 | __perf_event_init_context(ctx); | |
3549 | if (task) { | |
3550 | ctx->task = task; | |
3551 | get_task_struct(task); | |
0793a61d | 3552 | } |
eb184479 PZ |
3553 | ctx->pmu = pmu; |
3554 | ||
3555 | return ctx; | |
a63eaf34 PM |
3556 | } |
3557 | ||
2ebd4ffb MH |
3558 | static struct task_struct * |
3559 | find_lively_task_by_vpid(pid_t vpid) | |
3560 | { | |
3561 | struct task_struct *task; | |
0793a61d TG |
3562 | |
3563 | rcu_read_lock(); | |
2ebd4ffb | 3564 | if (!vpid) |
0793a61d TG |
3565 | task = current; |
3566 | else | |
2ebd4ffb | 3567 | task = find_task_by_vpid(vpid); |
0793a61d TG |
3568 | if (task) |
3569 | get_task_struct(task); | |
3570 | rcu_read_unlock(); | |
3571 | ||
3572 | if (!task) | |
3573 | return ERR_PTR(-ESRCH); | |
3574 | ||
2ebd4ffb | 3575 | return task; |
2ebd4ffb MH |
3576 | } |
3577 | ||
fe4b04fa PZ |
3578 | /* |
3579 | * Returns a matching context with refcount and pincount. | |
3580 | */ | |
108b02cf | 3581 | static struct perf_event_context * |
4af57ef2 YZ |
3582 | find_get_context(struct pmu *pmu, struct task_struct *task, |
3583 | struct perf_event *event) | |
0793a61d | 3584 | { |
211de6eb | 3585 | struct perf_event_context *ctx, *clone_ctx = NULL; |
22a4f650 | 3586 | struct perf_cpu_context *cpuctx; |
4af57ef2 | 3587 | void *task_ctx_data = NULL; |
25346b93 | 3588 | unsigned long flags; |
8dc85d54 | 3589 | int ctxn, err; |
4af57ef2 | 3590 | int cpu = event->cpu; |
0793a61d | 3591 | |
22a4ec72 | 3592 | if (!task) { |
cdd6c482 | 3593 | /* Must be root to operate on a CPU event: */ |
0764771d | 3594 | if (perf_paranoid_cpu() && !capable(CAP_SYS_ADMIN)) |
0793a61d TG |
3595 | return ERR_PTR(-EACCES); |
3596 | ||
0793a61d | 3597 | /* |
cdd6c482 | 3598 | * We could be clever and allow to attach a event to an |
0793a61d TG |
3599 | * offline CPU and activate it when the CPU comes up, but |
3600 | * that's for later. | |
3601 | */ | |
f6325e30 | 3602 | if (!cpu_online(cpu)) |
0793a61d TG |
3603 | return ERR_PTR(-ENODEV); |
3604 | ||
108b02cf | 3605 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); |
0793a61d | 3606 | ctx = &cpuctx->ctx; |
c93f7669 | 3607 | get_ctx(ctx); |
fe4b04fa | 3608 | ++ctx->pin_count; |
0793a61d | 3609 | |
0793a61d TG |
3610 | return ctx; |
3611 | } | |
3612 | ||
8dc85d54 PZ |
3613 | err = -EINVAL; |
3614 | ctxn = pmu->task_ctx_nr; | |
3615 | if (ctxn < 0) | |
3616 | goto errout; | |
3617 | ||
4af57ef2 YZ |
3618 | if (event->attach_state & PERF_ATTACH_TASK_DATA) { |
3619 | task_ctx_data = kzalloc(pmu->task_ctx_size, GFP_KERNEL); | |
3620 | if (!task_ctx_data) { | |
3621 | err = -ENOMEM; | |
3622 | goto errout; | |
3623 | } | |
3624 | } | |
3625 | ||
9ed6060d | 3626 | retry: |
8dc85d54 | 3627 | ctx = perf_lock_task_context(task, ctxn, &flags); |
c93f7669 | 3628 | if (ctx) { |
211de6eb | 3629 | clone_ctx = unclone_ctx(ctx); |
fe4b04fa | 3630 | ++ctx->pin_count; |
4af57ef2 YZ |
3631 | |
3632 | if (task_ctx_data && !ctx->task_ctx_data) { | |
3633 | ctx->task_ctx_data = task_ctx_data; | |
3634 | task_ctx_data = NULL; | |
3635 | } | |
e625cce1 | 3636 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
211de6eb PZ |
3637 | |
3638 | if (clone_ctx) | |
3639 | put_ctx(clone_ctx); | |
9137fb28 | 3640 | } else { |
eb184479 | 3641 | ctx = alloc_perf_context(pmu, task); |
c93f7669 PM |
3642 | err = -ENOMEM; |
3643 | if (!ctx) | |
3644 | goto errout; | |
eb184479 | 3645 | |
4af57ef2 YZ |
3646 | if (task_ctx_data) { |
3647 | ctx->task_ctx_data = task_ctx_data; | |
3648 | task_ctx_data = NULL; | |
3649 | } | |
3650 | ||
dbe08d82 ON |
3651 | err = 0; |
3652 | mutex_lock(&task->perf_event_mutex); | |
3653 | /* | |
3654 | * If it has already passed perf_event_exit_task(). | |
3655 | * we must see PF_EXITING, it takes this mutex too. | |
3656 | */ | |
3657 | if (task->flags & PF_EXITING) | |
3658 | err = -ESRCH; | |
3659 | else if (task->perf_event_ctxp[ctxn]) | |
3660 | err = -EAGAIN; | |
fe4b04fa | 3661 | else { |
9137fb28 | 3662 | get_ctx(ctx); |
fe4b04fa | 3663 | ++ctx->pin_count; |
dbe08d82 | 3664 | rcu_assign_pointer(task->perf_event_ctxp[ctxn], ctx); |
fe4b04fa | 3665 | } |
dbe08d82 ON |
3666 | mutex_unlock(&task->perf_event_mutex); |
3667 | ||
3668 | if (unlikely(err)) { | |
9137fb28 | 3669 | put_ctx(ctx); |
dbe08d82 ON |
3670 | |
3671 | if (err == -EAGAIN) | |
3672 | goto retry; | |
3673 | goto errout; | |
a63eaf34 PM |
3674 | } |
3675 | } | |
3676 | ||
4af57ef2 | 3677 | kfree(task_ctx_data); |
0793a61d | 3678 | return ctx; |
c93f7669 | 3679 | |
9ed6060d | 3680 | errout: |
4af57ef2 | 3681 | kfree(task_ctx_data); |
c93f7669 | 3682 | return ERR_PTR(err); |
0793a61d TG |
3683 | } |
3684 | ||
6fb2915d | 3685 | static void perf_event_free_filter(struct perf_event *event); |
2541517c | 3686 | static void perf_event_free_bpf_prog(struct perf_event *event); |
6fb2915d | 3687 | |
cdd6c482 | 3688 | static void free_event_rcu(struct rcu_head *head) |
592903cd | 3689 | { |
cdd6c482 | 3690 | struct perf_event *event; |
592903cd | 3691 | |
cdd6c482 IM |
3692 | event = container_of(head, struct perf_event, rcu_head); |
3693 | if (event->ns) | |
3694 | put_pid_ns(event->ns); | |
6fb2915d | 3695 | perf_event_free_filter(event); |
cdd6c482 | 3696 | kfree(event); |
592903cd PZ |
3697 | } |
3698 | ||
b69cf536 PZ |
3699 | static void ring_buffer_attach(struct perf_event *event, |
3700 | struct ring_buffer *rb); | |
925d519a | 3701 | |
f2fb6bef KL |
3702 | static void detach_sb_event(struct perf_event *event) |
3703 | { | |
3704 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
3705 | ||
3706 | raw_spin_lock(&pel->lock); | |
3707 | list_del_rcu(&event->sb_list); | |
3708 | raw_spin_unlock(&pel->lock); | |
3709 | } | |
3710 | ||
a4f144eb | 3711 | static bool is_sb_event(struct perf_event *event) |
f2fb6bef | 3712 | { |
a4f144eb DCC |
3713 | struct perf_event_attr *attr = &event->attr; |
3714 | ||
f2fb6bef | 3715 | if (event->parent) |
a4f144eb | 3716 | return false; |
f2fb6bef KL |
3717 | |
3718 | if (event->attach_state & PERF_ATTACH_TASK) | |
a4f144eb | 3719 | return false; |
f2fb6bef | 3720 | |
a4f144eb DCC |
3721 | if (attr->mmap || attr->mmap_data || attr->mmap2 || |
3722 | attr->comm || attr->comm_exec || | |
3723 | attr->task || | |
3724 | attr->context_switch) | |
3725 | return true; | |
3726 | return false; | |
3727 | } | |
3728 | ||
3729 | static void unaccount_pmu_sb_event(struct perf_event *event) | |
3730 | { | |
3731 | if (is_sb_event(event)) | |
3732 | detach_sb_event(event); | |
f2fb6bef KL |
3733 | } |
3734 | ||
4beb31f3 | 3735 | static void unaccount_event_cpu(struct perf_event *event, int cpu) |
f1600952 | 3736 | { |
4beb31f3 FW |
3737 | if (event->parent) |
3738 | return; | |
3739 | ||
4beb31f3 FW |
3740 | if (is_cgroup_event(event)) |
3741 | atomic_dec(&per_cpu(perf_cgroup_events, cpu)); | |
3742 | } | |
925d519a | 3743 | |
555e0c1e FW |
3744 | #ifdef CONFIG_NO_HZ_FULL |
3745 | static DEFINE_SPINLOCK(nr_freq_lock); | |
3746 | #endif | |
3747 | ||
3748 | static void unaccount_freq_event_nohz(void) | |
3749 | { | |
3750 | #ifdef CONFIG_NO_HZ_FULL | |
3751 | spin_lock(&nr_freq_lock); | |
3752 | if (atomic_dec_and_test(&nr_freq_events)) | |
3753 | tick_nohz_dep_clear(TICK_DEP_BIT_PERF_EVENTS); | |
3754 | spin_unlock(&nr_freq_lock); | |
3755 | #endif | |
3756 | } | |
3757 | ||
3758 | static void unaccount_freq_event(void) | |
3759 | { | |
3760 | if (tick_nohz_full_enabled()) | |
3761 | unaccount_freq_event_nohz(); | |
3762 | else | |
3763 | atomic_dec(&nr_freq_events); | |
3764 | } | |
3765 | ||
4beb31f3 FW |
3766 | static void unaccount_event(struct perf_event *event) |
3767 | { | |
25432ae9 PZ |
3768 | bool dec = false; |
3769 | ||
4beb31f3 FW |
3770 | if (event->parent) |
3771 | return; | |
3772 | ||
3773 | if (event->attach_state & PERF_ATTACH_TASK) | |
25432ae9 | 3774 | dec = true; |
4beb31f3 FW |
3775 | if (event->attr.mmap || event->attr.mmap_data) |
3776 | atomic_dec(&nr_mmap_events); | |
3777 | if (event->attr.comm) | |
3778 | atomic_dec(&nr_comm_events); | |
3779 | if (event->attr.task) | |
3780 | atomic_dec(&nr_task_events); | |
948b26b6 | 3781 | if (event->attr.freq) |
555e0c1e | 3782 | unaccount_freq_event(); |
45ac1403 | 3783 | if (event->attr.context_switch) { |
25432ae9 | 3784 | dec = true; |
45ac1403 AH |
3785 | atomic_dec(&nr_switch_events); |
3786 | } | |
4beb31f3 | 3787 | if (is_cgroup_event(event)) |
25432ae9 | 3788 | dec = true; |
4beb31f3 | 3789 | if (has_branch_stack(event)) |
25432ae9 PZ |
3790 | dec = true; |
3791 | ||
9107c89e PZ |
3792 | if (dec) { |
3793 | if (!atomic_add_unless(&perf_sched_count, -1, 1)) | |
3794 | schedule_delayed_work(&perf_sched_work, HZ); | |
3795 | } | |
4beb31f3 FW |
3796 | |
3797 | unaccount_event_cpu(event, event->cpu); | |
f2fb6bef KL |
3798 | |
3799 | unaccount_pmu_sb_event(event); | |
4beb31f3 | 3800 | } |
925d519a | 3801 | |
9107c89e PZ |
3802 | static void perf_sched_delayed(struct work_struct *work) |
3803 | { | |
3804 | mutex_lock(&perf_sched_mutex); | |
3805 | if (atomic_dec_and_test(&perf_sched_count)) | |
3806 | static_branch_disable(&perf_sched_events); | |
3807 | mutex_unlock(&perf_sched_mutex); | |
3808 | } | |
3809 | ||
bed5b25a AS |
3810 | /* |
3811 | * The following implement mutual exclusion of events on "exclusive" pmus | |
3812 | * (PERF_PMU_CAP_EXCLUSIVE). Such pmus can only have one event scheduled | |
3813 | * at a time, so we disallow creating events that might conflict, namely: | |
3814 | * | |
3815 | * 1) cpu-wide events in the presence of per-task events, | |
3816 | * 2) per-task events in the presence of cpu-wide events, | |
3817 | * 3) two matching events on the same context. | |
3818 | * | |
3819 | * The former two cases are handled in the allocation path (perf_event_alloc(), | |
a0733e69 | 3820 | * _free_event()), the latter -- before the first perf_install_in_context(). |
bed5b25a AS |
3821 | */ |
3822 | static int exclusive_event_init(struct perf_event *event) | |
3823 | { | |
3824 | struct pmu *pmu = event->pmu; | |
3825 | ||
3826 | if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE)) | |
3827 | return 0; | |
3828 | ||
3829 | /* | |
3830 | * Prevent co-existence of per-task and cpu-wide events on the | |
3831 | * same exclusive pmu. | |
3832 | * | |
3833 | * Negative pmu::exclusive_cnt means there are cpu-wide | |
3834 | * events on this "exclusive" pmu, positive means there are | |
3835 | * per-task events. | |
3836 | * | |
3837 | * Since this is called in perf_event_alloc() path, event::ctx | |
3838 | * doesn't exist yet; it is, however, safe to use PERF_ATTACH_TASK | |
3839 | * to mean "per-task event", because unlike other attach states it | |
3840 | * never gets cleared. | |
3841 | */ | |
3842 | if (event->attach_state & PERF_ATTACH_TASK) { | |
3843 | if (!atomic_inc_unless_negative(&pmu->exclusive_cnt)) | |
3844 | return -EBUSY; | |
3845 | } else { | |
3846 | if (!atomic_dec_unless_positive(&pmu->exclusive_cnt)) | |
3847 | return -EBUSY; | |
3848 | } | |
3849 | ||
3850 | return 0; | |
3851 | } | |
3852 | ||
3853 | static void exclusive_event_destroy(struct perf_event *event) | |
3854 | { | |
3855 | struct pmu *pmu = event->pmu; | |
3856 | ||
3857 | if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE)) | |
3858 | return; | |
3859 | ||
3860 | /* see comment in exclusive_event_init() */ | |
3861 | if (event->attach_state & PERF_ATTACH_TASK) | |
3862 | atomic_dec(&pmu->exclusive_cnt); | |
3863 | else | |
3864 | atomic_inc(&pmu->exclusive_cnt); | |
3865 | } | |
3866 | ||
3867 | static bool exclusive_event_match(struct perf_event *e1, struct perf_event *e2) | |
3868 | { | |
3869 | if ((e1->pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE) && | |
3870 | (e1->cpu == e2->cpu || | |
3871 | e1->cpu == -1 || | |
3872 | e2->cpu == -1)) | |
3873 | return true; | |
3874 | return false; | |
3875 | } | |
3876 | ||
3877 | /* Called under the same ctx::mutex as perf_install_in_context() */ | |
3878 | static bool exclusive_event_installable(struct perf_event *event, | |
3879 | struct perf_event_context *ctx) | |
3880 | { | |
3881 | struct perf_event *iter_event; | |
3882 | struct pmu *pmu = event->pmu; | |
3883 | ||
3884 | if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE)) | |
3885 | return true; | |
3886 | ||
3887 | list_for_each_entry(iter_event, &ctx->event_list, event_entry) { | |
3888 | if (exclusive_event_match(iter_event, event)) | |
3889 | return false; | |
3890 | } | |
3891 | ||
3892 | return true; | |
3893 | } | |
3894 | ||
375637bc AS |
3895 | static void perf_addr_filters_splice(struct perf_event *event, |
3896 | struct list_head *head); | |
3897 | ||
683ede43 | 3898 | static void _free_event(struct perf_event *event) |
f1600952 | 3899 | { |
e360adbe | 3900 | irq_work_sync(&event->pending); |
925d519a | 3901 | |
4beb31f3 | 3902 | unaccount_event(event); |
9ee318a7 | 3903 | |
76369139 | 3904 | if (event->rb) { |
9bb5d40c PZ |
3905 | /* |
3906 | * Can happen when we close an event with re-directed output. | |
3907 | * | |
3908 | * Since we have a 0 refcount, perf_mmap_close() will skip | |
3909 | * over us; possibly making our ring_buffer_put() the last. | |
3910 | */ | |
3911 | mutex_lock(&event->mmap_mutex); | |
b69cf536 | 3912 | ring_buffer_attach(event, NULL); |
9bb5d40c | 3913 | mutex_unlock(&event->mmap_mutex); |
a4be7c27 PZ |
3914 | } |
3915 | ||
e5d1367f SE |
3916 | if (is_cgroup_event(event)) |
3917 | perf_detach_cgroup(event); | |
3918 | ||
a0733e69 PZ |
3919 | if (!event->parent) { |
3920 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) | |
3921 | put_callchain_buffers(); | |
3922 | } | |
3923 | ||
3924 | perf_event_free_bpf_prog(event); | |
375637bc AS |
3925 | perf_addr_filters_splice(event, NULL); |
3926 | kfree(event->addr_filters_offs); | |
a0733e69 PZ |
3927 | |
3928 | if (event->destroy) | |
3929 | event->destroy(event); | |
3930 | ||
3931 | if (event->ctx) | |
3932 | put_ctx(event->ctx); | |
3933 | ||
62a92c8f AS |
3934 | exclusive_event_destroy(event); |
3935 | module_put(event->pmu->module); | |
a0733e69 PZ |
3936 | |
3937 | call_rcu(&event->rcu_head, free_event_rcu); | |
f1600952 PZ |
3938 | } |
3939 | ||
683ede43 PZ |
3940 | /* |
3941 | * Used to free events which have a known refcount of 1, such as in error paths | |
3942 | * where the event isn't exposed yet and inherited events. | |
3943 | */ | |
3944 | static void free_event(struct perf_event *event) | |
0793a61d | 3945 | { |
683ede43 PZ |
3946 | if (WARN(atomic_long_cmpxchg(&event->refcount, 1, 0) != 1, |
3947 | "unexpected event refcount: %ld; ptr=%p\n", | |
3948 | atomic_long_read(&event->refcount), event)) { | |
3949 | /* leak to avoid use-after-free */ | |
3950 | return; | |
3951 | } | |
0793a61d | 3952 | |
683ede43 | 3953 | _free_event(event); |
0793a61d TG |
3954 | } |
3955 | ||
a66a3052 | 3956 | /* |
f8697762 | 3957 | * Remove user event from the owner task. |
a66a3052 | 3958 | */ |
f8697762 | 3959 | static void perf_remove_from_owner(struct perf_event *event) |
fb0459d7 | 3960 | { |
8882135b | 3961 | struct task_struct *owner; |
fb0459d7 | 3962 | |
8882135b | 3963 | rcu_read_lock(); |
8882135b | 3964 | /* |
f47c02c0 PZ |
3965 | * Matches the smp_store_release() in perf_event_exit_task(). If we |
3966 | * observe !owner it means the list deletion is complete and we can | |
3967 | * indeed free this event, otherwise we need to serialize on | |
8882135b PZ |
3968 | * owner->perf_event_mutex. |
3969 | */ | |
f47c02c0 | 3970 | owner = lockless_dereference(event->owner); |
8882135b PZ |
3971 | if (owner) { |
3972 | /* | |
3973 | * Since delayed_put_task_struct() also drops the last | |
3974 | * task reference we can safely take a new reference | |
3975 | * while holding the rcu_read_lock(). | |
3976 | */ | |
3977 | get_task_struct(owner); | |
3978 | } | |
3979 | rcu_read_unlock(); | |
3980 | ||
3981 | if (owner) { | |
f63a8daa PZ |
3982 | /* |
3983 | * If we're here through perf_event_exit_task() we're already | |
3984 | * holding ctx->mutex which would be an inversion wrt. the | |
3985 | * normal lock order. | |
3986 | * | |
3987 | * However we can safely take this lock because its the child | |
3988 | * ctx->mutex. | |
3989 | */ | |
3990 | mutex_lock_nested(&owner->perf_event_mutex, SINGLE_DEPTH_NESTING); | |
3991 | ||
8882135b PZ |
3992 | /* |
3993 | * We have to re-check the event->owner field, if it is cleared | |
3994 | * we raced with perf_event_exit_task(), acquiring the mutex | |
3995 | * ensured they're done, and we can proceed with freeing the | |
3996 | * event. | |
3997 | */ | |
f47c02c0 | 3998 | if (event->owner) { |
8882135b | 3999 | list_del_init(&event->owner_entry); |
f47c02c0 PZ |
4000 | smp_store_release(&event->owner, NULL); |
4001 | } | |
8882135b PZ |
4002 | mutex_unlock(&owner->perf_event_mutex); |
4003 | put_task_struct(owner); | |
4004 | } | |
f8697762 JO |
4005 | } |
4006 | ||
f8697762 JO |
4007 | static void put_event(struct perf_event *event) |
4008 | { | |
f8697762 JO |
4009 | if (!atomic_long_dec_and_test(&event->refcount)) |
4010 | return; | |
4011 | ||
c6e5b732 PZ |
4012 | _free_event(event); |
4013 | } | |
4014 | ||
4015 | /* | |
4016 | * Kill an event dead; while event:refcount will preserve the event | |
4017 | * object, it will not preserve its functionality. Once the last 'user' | |
4018 | * gives up the object, we'll destroy the thing. | |
4019 | */ | |
4020 | int perf_event_release_kernel(struct perf_event *event) | |
4021 | { | |
a4f4bb6d | 4022 | struct perf_event_context *ctx = event->ctx; |
c6e5b732 PZ |
4023 | struct perf_event *child, *tmp; |
4024 | ||
a4f4bb6d PZ |
4025 | /* |
4026 | * If we got here through err_file: fput(event_file); we will not have | |
4027 | * attached to a context yet. | |
4028 | */ | |
4029 | if (!ctx) { | |
4030 | WARN_ON_ONCE(event->attach_state & | |
4031 | (PERF_ATTACH_CONTEXT|PERF_ATTACH_GROUP)); | |
4032 | goto no_ctx; | |
4033 | } | |
4034 | ||
f8697762 JO |
4035 | if (!is_kernel_event(event)) |
4036 | perf_remove_from_owner(event); | |
8882135b | 4037 | |
5fa7c8ec | 4038 | ctx = perf_event_ctx_lock(event); |
a83fe28e | 4039 | WARN_ON_ONCE(ctx->parent_ctx); |
a69b0ca4 | 4040 | perf_remove_from_context(event, DETACH_GROUP); |
683ede43 | 4041 | |
a69b0ca4 | 4042 | raw_spin_lock_irq(&ctx->lock); |
683ede43 | 4043 | /* |
a69b0ca4 PZ |
4044 | * Mark this even as STATE_DEAD, there is no external reference to it |
4045 | * anymore. | |
683ede43 | 4046 | * |
a69b0ca4 PZ |
4047 | * Anybody acquiring event->child_mutex after the below loop _must_ |
4048 | * also see this, most importantly inherit_event() which will avoid | |
4049 | * placing more children on the list. | |
683ede43 | 4050 | * |
c6e5b732 PZ |
4051 | * Thus this guarantees that we will in fact observe and kill _ALL_ |
4052 | * child events. | |
683ede43 | 4053 | */ |
a69b0ca4 PZ |
4054 | event->state = PERF_EVENT_STATE_DEAD; |
4055 | raw_spin_unlock_irq(&ctx->lock); | |
4056 | ||
4057 | perf_event_ctx_unlock(event, ctx); | |
683ede43 | 4058 | |
c6e5b732 PZ |
4059 | again: |
4060 | mutex_lock(&event->child_mutex); | |
4061 | list_for_each_entry(child, &event->child_list, child_list) { | |
a6fa941d | 4062 | |
c6e5b732 PZ |
4063 | /* |
4064 | * Cannot change, child events are not migrated, see the | |
4065 | * comment with perf_event_ctx_lock_nested(). | |
4066 | */ | |
4067 | ctx = lockless_dereference(child->ctx); | |
4068 | /* | |
4069 | * Since child_mutex nests inside ctx::mutex, we must jump | |
4070 | * through hoops. We start by grabbing a reference on the ctx. | |
4071 | * | |
4072 | * Since the event cannot get freed while we hold the | |
4073 | * child_mutex, the context must also exist and have a !0 | |
4074 | * reference count. | |
4075 | */ | |
4076 | get_ctx(ctx); | |
4077 | ||
4078 | /* | |
4079 | * Now that we have a ctx ref, we can drop child_mutex, and | |
4080 | * acquire ctx::mutex without fear of it going away. Then we | |
4081 | * can re-acquire child_mutex. | |
4082 | */ | |
4083 | mutex_unlock(&event->child_mutex); | |
4084 | mutex_lock(&ctx->mutex); | |
4085 | mutex_lock(&event->child_mutex); | |
4086 | ||
4087 | /* | |
4088 | * Now that we hold ctx::mutex and child_mutex, revalidate our | |
4089 | * state, if child is still the first entry, it didn't get freed | |
4090 | * and we can continue doing so. | |
4091 | */ | |
4092 | tmp = list_first_entry_or_null(&event->child_list, | |
4093 | struct perf_event, child_list); | |
4094 | if (tmp == child) { | |
4095 | perf_remove_from_context(child, DETACH_GROUP); | |
4096 | list_del(&child->child_list); | |
4097 | free_event(child); | |
4098 | /* | |
4099 | * This matches the refcount bump in inherit_event(); | |
4100 | * this can't be the last reference. | |
4101 | */ | |
4102 | put_event(event); | |
4103 | } | |
4104 | ||
4105 | mutex_unlock(&event->child_mutex); | |
4106 | mutex_unlock(&ctx->mutex); | |
4107 | put_ctx(ctx); | |
4108 | goto again; | |
4109 | } | |
4110 | mutex_unlock(&event->child_mutex); | |
4111 | ||
a4f4bb6d PZ |
4112 | no_ctx: |
4113 | put_event(event); /* Must be the 'last' reference */ | |
683ede43 PZ |
4114 | return 0; |
4115 | } | |
4116 | EXPORT_SYMBOL_GPL(perf_event_release_kernel); | |
4117 | ||
8b10c5e2 PZ |
4118 | /* |
4119 | * Called when the last reference to the file is gone. | |
4120 | */ | |
a6fa941d AV |
4121 | static int perf_release(struct inode *inode, struct file *file) |
4122 | { | |
c6e5b732 | 4123 | perf_event_release_kernel(file->private_data); |
a6fa941d | 4124 | return 0; |
fb0459d7 | 4125 | } |
fb0459d7 | 4126 | |
59ed446f | 4127 | u64 perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) |
e53c0994 | 4128 | { |
cdd6c482 | 4129 | struct perf_event *child; |
e53c0994 PZ |
4130 | u64 total = 0; |
4131 | ||
59ed446f PZ |
4132 | *enabled = 0; |
4133 | *running = 0; | |
4134 | ||
6f10581a | 4135 | mutex_lock(&event->child_mutex); |
01add3ea | 4136 | |
7d88962e | 4137 | (void)perf_event_read(event, false); |
01add3ea SB |
4138 | total += perf_event_count(event); |
4139 | ||
59ed446f PZ |
4140 | *enabled += event->total_time_enabled + |
4141 | atomic64_read(&event->child_total_time_enabled); | |
4142 | *running += event->total_time_running + | |
4143 | atomic64_read(&event->child_total_time_running); | |
4144 | ||
4145 | list_for_each_entry(child, &event->child_list, child_list) { | |
7d88962e | 4146 | (void)perf_event_read(child, false); |
01add3ea | 4147 | total += perf_event_count(child); |
59ed446f PZ |
4148 | *enabled += child->total_time_enabled; |
4149 | *running += child->total_time_running; | |
4150 | } | |
6f10581a | 4151 | mutex_unlock(&event->child_mutex); |
e53c0994 PZ |
4152 | |
4153 | return total; | |
4154 | } | |
fb0459d7 | 4155 | EXPORT_SYMBOL_GPL(perf_event_read_value); |
e53c0994 | 4156 | |
7d88962e | 4157 | static int __perf_read_group_add(struct perf_event *leader, |
fa8c2693 | 4158 | u64 read_format, u64 *values) |
3dab77fb | 4159 | { |
fa8c2693 PZ |
4160 | struct perf_event *sub; |
4161 | int n = 1; /* skip @nr */ | |
7d88962e | 4162 | int ret; |
f63a8daa | 4163 | |
7d88962e SB |
4164 | ret = perf_event_read(leader, true); |
4165 | if (ret) | |
4166 | return ret; | |
abf4868b | 4167 | |
fa8c2693 PZ |
4168 | /* |
4169 | * Since we co-schedule groups, {enabled,running} times of siblings | |
4170 | * will be identical to those of the leader, so we only publish one | |
4171 | * set. | |
4172 | */ | |
4173 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { | |
4174 | values[n++] += leader->total_time_enabled + | |
4175 | atomic64_read(&leader->child_total_time_enabled); | |
4176 | } | |
3dab77fb | 4177 | |
fa8c2693 PZ |
4178 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { |
4179 | values[n++] += leader->total_time_running + | |
4180 | atomic64_read(&leader->child_total_time_running); | |
4181 | } | |
4182 | ||
4183 | /* | |
4184 | * Write {count,id} tuples for every sibling. | |
4185 | */ | |
4186 | values[n++] += perf_event_count(leader); | |
abf4868b PZ |
4187 | if (read_format & PERF_FORMAT_ID) |
4188 | values[n++] = primary_event_id(leader); | |
3dab77fb | 4189 | |
fa8c2693 PZ |
4190 | list_for_each_entry(sub, &leader->sibling_list, group_entry) { |
4191 | values[n++] += perf_event_count(sub); | |
4192 | if (read_format & PERF_FORMAT_ID) | |
4193 | values[n++] = primary_event_id(sub); | |
4194 | } | |
7d88962e SB |
4195 | |
4196 | return 0; | |
fa8c2693 | 4197 | } |
3dab77fb | 4198 | |
fa8c2693 PZ |
4199 | static int perf_read_group(struct perf_event *event, |
4200 | u64 read_format, char __user *buf) | |
4201 | { | |
4202 | struct perf_event *leader = event->group_leader, *child; | |
4203 | struct perf_event_context *ctx = leader->ctx; | |
7d88962e | 4204 | int ret; |
fa8c2693 | 4205 | u64 *values; |
3dab77fb | 4206 | |
fa8c2693 | 4207 | lockdep_assert_held(&ctx->mutex); |
3dab77fb | 4208 | |
fa8c2693 PZ |
4209 | values = kzalloc(event->read_size, GFP_KERNEL); |
4210 | if (!values) | |
4211 | return -ENOMEM; | |
3dab77fb | 4212 | |
fa8c2693 PZ |
4213 | values[0] = 1 + leader->nr_siblings; |
4214 | ||
4215 | /* | |
4216 | * By locking the child_mutex of the leader we effectively | |
4217 | * lock the child list of all siblings.. XXX explain how. | |
4218 | */ | |
4219 | mutex_lock(&leader->child_mutex); | |
abf4868b | 4220 | |
7d88962e SB |
4221 | ret = __perf_read_group_add(leader, read_format, values); |
4222 | if (ret) | |
4223 | goto unlock; | |
4224 | ||
4225 | list_for_each_entry(child, &leader->child_list, child_list) { | |
4226 | ret = __perf_read_group_add(child, read_format, values); | |
4227 | if (ret) | |
4228 | goto unlock; | |
4229 | } | |
abf4868b | 4230 | |
fa8c2693 | 4231 | mutex_unlock(&leader->child_mutex); |
abf4868b | 4232 | |
7d88962e | 4233 | ret = event->read_size; |
fa8c2693 PZ |
4234 | if (copy_to_user(buf, values, event->read_size)) |
4235 | ret = -EFAULT; | |
7d88962e | 4236 | goto out; |
fa8c2693 | 4237 | |
7d88962e SB |
4238 | unlock: |
4239 | mutex_unlock(&leader->child_mutex); | |
4240 | out: | |
fa8c2693 | 4241 | kfree(values); |
abf4868b | 4242 | return ret; |
3dab77fb PZ |
4243 | } |
4244 | ||
b15f495b | 4245 | static int perf_read_one(struct perf_event *event, |
3dab77fb PZ |
4246 | u64 read_format, char __user *buf) |
4247 | { | |
59ed446f | 4248 | u64 enabled, running; |
3dab77fb PZ |
4249 | u64 values[4]; |
4250 | int n = 0; | |
4251 | ||
59ed446f PZ |
4252 | values[n++] = perf_event_read_value(event, &enabled, &running); |
4253 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
4254 | values[n++] = enabled; | |
4255 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
4256 | values[n++] = running; | |
3dab77fb | 4257 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 4258 | values[n++] = primary_event_id(event); |
3dab77fb PZ |
4259 | |
4260 | if (copy_to_user(buf, values, n * sizeof(u64))) | |
4261 | return -EFAULT; | |
4262 | ||
4263 | return n * sizeof(u64); | |
4264 | } | |
4265 | ||
dc633982 JO |
4266 | static bool is_event_hup(struct perf_event *event) |
4267 | { | |
4268 | bool no_children; | |
4269 | ||
a69b0ca4 | 4270 | if (event->state > PERF_EVENT_STATE_EXIT) |
dc633982 JO |
4271 | return false; |
4272 | ||
4273 | mutex_lock(&event->child_mutex); | |
4274 | no_children = list_empty(&event->child_list); | |
4275 | mutex_unlock(&event->child_mutex); | |
4276 | return no_children; | |
4277 | } | |
4278 | ||
0793a61d | 4279 | /* |
cdd6c482 | 4280 | * Read the performance event - simple non blocking version for now |
0793a61d TG |
4281 | */ |
4282 | static ssize_t | |
b15f495b | 4283 | __perf_read(struct perf_event *event, char __user *buf, size_t count) |
0793a61d | 4284 | { |
cdd6c482 | 4285 | u64 read_format = event->attr.read_format; |
3dab77fb | 4286 | int ret; |
0793a61d | 4287 | |
3b6f9e5c | 4288 | /* |
cdd6c482 | 4289 | * Return end-of-file for a read on a event that is in |
3b6f9e5c PM |
4290 | * error state (i.e. because it was pinned but it couldn't be |
4291 | * scheduled on to the CPU at some point). | |
4292 | */ | |
cdd6c482 | 4293 | if (event->state == PERF_EVENT_STATE_ERROR) |
3b6f9e5c PM |
4294 | return 0; |
4295 | ||
c320c7b7 | 4296 | if (count < event->read_size) |
3dab77fb PZ |
4297 | return -ENOSPC; |
4298 | ||
cdd6c482 | 4299 | WARN_ON_ONCE(event->ctx->parent_ctx); |
3dab77fb | 4300 | if (read_format & PERF_FORMAT_GROUP) |
b15f495b | 4301 | ret = perf_read_group(event, read_format, buf); |
3dab77fb | 4302 | else |
b15f495b | 4303 | ret = perf_read_one(event, read_format, buf); |
0793a61d | 4304 | |
3dab77fb | 4305 | return ret; |
0793a61d TG |
4306 | } |
4307 | ||
0793a61d TG |
4308 | static ssize_t |
4309 | perf_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) | |
4310 | { | |
cdd6c482 | 4311 | struct perf_event *event = file->private_data; |
f63a8daa PZ |
4312 | struct perf_event_context *ctx; |
4313 | int ret; | |
0793a61d | 4314 | |
f63a8daa | 4315 | ctx = perf_event_ctx_lock(event); |
b15f495b | 4316 | ret = __perf_read(event, buf, count); |
f63a8daa PZ |
4317 | perf_event_ctx_unlock(event, ctx); |
4318 | ||
4319 | return ret; | |
0793a61d TG |
4320 | } |
4321 | ||
4322 | static unsigned int perf_poll(struct file *file, poll_table *wait) | |
4323 | { | |
cdd6c482 | 4324 | struct perf_event *event = file->private_data; |
76369139 | 4325 | struct ring_buffer *rb; |
61b67684 | 4326 | unsigned int events = POLLHUP; |
c7138f37 | 4327 | |
e708d7ad | 4328 | poll_wait(file, &event->waitq, wait); |
179033b3 | 4329 | |
dc633982 | 4330 | if (is_event_hup(event)) |
179033b3 | 4331 | return events; |
c7138f37 | 4332 | |
10c6db11 | 4333 | /* |
9bb5d40c PZ |
4334 | * Pin the event->rb by taking event->mmap_mutex; otherwise |
4335 | * perf_event_set_output() can swizzle our rb and make us miss wakeups. | |
10c6db11 PZ |
4336 | */ |
4337 | mutex_lock(&event->mmap_mutex); | |
9bb5d40c PZ |
4338 | rb = event->rb; |
4339 | if (rb) | |
76369139 | 4340 | events = atomic_xchg(&rb->poll, 0); |
10c6db11 | 4341 | mutex_unlock(&event->mmap_mutex); |
0793a61d TG |
4342 | return events; |
4343 | } | |
4344 | ||
f63a8daa | 4345 | static void _perf_event_reset(struct perf_event *event) |
6de6a7b9 | 4346 | { |
7d88962e | 4347 | (void)perf_event_read(event, false); |
e7850595 | 4348 | local64_set(&event->count, 0); |
cdd6c482 | 4349 | perf_event_update_userpage(event); |
3df5edad PZ |
4350 | } |
4351 | ||
c93f7669 | 4352 | /* |
cdd6c482 IM |
4353 | * Holding the top-level event's child_mutex means that any |
4354 | * descendant process that has inherited this event will block | |
8ba289b8 | 4355 | * in perf_event_exit_event() if it goes to exit, thus satisfying the |
cdd6c482 | 4356 | * task existence requirements of perf_event_enable/disable. |
c93f7669 | 4357 | */ |
cdd6c482 IM |
4358 | static void perf_event_for_each_child(struct perf_event *event, |
4359 | void (*func)(struct perf_event *)) | |
3df5edad | 4360 | { |
cdd6c482 | 4361 | struct perf_event *child; |
3df5edad | 4362 | |
cdd6c482 | 4363 | WARN_ON_ONCE(event->ctx->parent_ctx); |
f63a8daa | 4364 | |
cdd6c482 IM |
4365 | mutex_lock(&event->child_mutex); |
4366 | func(event); | |
4367 | list_for_each_entry(child, &event->child_list, child_list) | |
3df5edad | 4368 | func(child); |
cdd6c482 | 4369 | mutex_unlock(&event->child_mutex); |
3df5edad PZ |
4370 | } |
4371 | ||
cdd6c482 IM |
4372 | static void perf_event_for_each(struct perf_event *event, |
4373 | void (*func)(struct perf_event *)) | |
3df5edad | 4374 | { |
cdd6c482 IM |
4375 | struct perf_event_context *ctx = event->ctx; |
4376 | struct perf_event *sibling; | |
3df5edad | 4377 | |
f63a8daa PZ |
4378 | lockdep_assert_held(&ctx->mutex); |
4379 | ||
cdd6c482 | 4380 | event = event->group_leader; |
75f937f2 | 4381 | |
cdd6c482 | 4382 | perf_event_for_each_child(event, func); |
cdd6c482 | 4383 | list_for_each_entry(sibling, &event->sibling_list, group_entry) |
724b6daa | 4384 | perf_event_for_each_child(sibling, func); |
6de6a7b9 PZ |
4385 | } |
4386 | ||
fae3fde6 PZ |
4387 | static void __perf_event_period(struct perf_event *event, |
4388 | struct perf_cpu_context *cpuctx, | |
4389 | struct perf_event_context *ctx, | |
4390 | void *info) | |
c7999c6f | 4391 | { |
fae3fde6 | 4392 | u64 value = *((u64 *)info); |
c7999c6f | 4393 | bool active; |
08247e31 | 4394 | |
cdd6c482 | 4395 | if (event->attr.freq) { |
cdd6c482 | 4396 | event->attr.sample_freq = value; |
08247e31 | 4397 | } else { |
cdd6c482 IM |
4398 | event->attr.sample_period = value; |
4399 | event->hw.sample_period = value; | |
08247e31 | 4400 | } |
bad7192b PZ |
4401 | |
4402 | active = (event->state == PERF_EVENT_STATE_ACTIVE); | |
4403 | if (active) { | |
4404 | perf_pmu_disable(ctx->pmu); | |
1e02cd40 PZ |
4405 | /* |
4406 | * We could be throttled; unthrottle now to avoid the tick | |
4407 | * trying to unthrottle while we already re-started the event. | |
4408 | */ | |
4409 | if (event->hw.interrupts == MAX_INTERRUPTS) { | |
4410 | event->hw.interrupts = 0; | |
4411 | perf_log_throttle(event, 1); | |
4412 | } | |
bad7192b PZ |
4413 | event->pmu->stop(event, PERF_EF_UPDATE); |
4414 | } | |
4415 | ||
4416 | local64_set(&event->hw.period_left, 0); | |
4417 | ||
4418 | if (active) { | |
4419 | event->pmu->start(event, PERF_EF_RELOAD); | |
4420 | perf_pmu_enable(ctx->pmu); | |
4421 | } | |
c7999c6f PZ |
4422 | } |
4423 | ||
4424 | static int perf_event_period(struct perf_event *event, u64 __user *arg) | |
4425 | { | |
c7999c6f PZ |
4426 | u64 value; |
4427 | ||
4428 | if (!is_sampling_event(event)) | |
4429 | return -EINVAL; | |
4430 | ||
4431 | if (copy_from_user(&value, arg, sizeof(value))) | |
4432 | return -EFAULT; | |
4433 | ||
4434 | if (!value) | |
4435 | return -EINVAL; | |
4436 | ||
4437 | if (event->attr.freq && value > sysctl_perf_event_sample_rate) | |
4438 | return -EINVAL; | |
4439 | ||
fae3fde6 | 4440 | event_function_call(event, __perf_event_period, &value); |
08247e31 | 4441 | |
c7999c6f | 4442 | return 0; |
08247e31 PZ |
4443 | } |
4444 | ||
ac9721f3 PZ |
4445 | static const struct file_operations perf_fops; |
4446 | ||
2903ff01 | 4447 | static inline int perf_fget_light(int fd, struct fd *p) |
ac9721f3 | 4448 | { |
2903ff01 AV |
4449 | struct fd f = fdget(fd); |
4450 | if (!f.file) | |
4451 | return -EBADF; | |
ac9721f3 | 4452 | |
2903ff01 AV |
4453 | if (f.file->f_op != &perf_fops) { |
4454 | fdput(f); | |
4455 | return -EBADF; | |
ac9721f3 | 4456 | } |
2903ff01 AV |
4457 | *p = f; |
4458 | return 0; | |
ac9721f3 PZ |
4459 | } |
4460 | ||
4461 | static int perf_event_set_output(struct perf_event *event, | |
4462 | struct perf_event *output_event); | |
6fb2915d | 4463 | static int perf_event_set_filter(struct perf_event *event, void __user *arg); |
2541517c | 4464 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd); |
a4be7c27 | 4465 | |
f63a8daa | 4466 | static long _perf_ioctl(struct perf_event *event, unsigned int cmd, unsigned long arg) |
d859e29f | 4467 | { |
cdd6c482 | 4468 | void (*func)(struct perf_event *); |
3df5edad | 4469 | u32 flags = arg; |
d859e29f PM |
4470 | |
4471 | switch (cmd) { | |
cdd6c482 | 4472 | case PERF_EVENT_IOC_ENABLE: |
f63a8daa | 4473 | func = _perf_event_enable; |
d859e29f | 4474 | break; |
cdd6c482 | 4475 | case PERF_EVENT_IOC_DISABLE: |
f63a8daa | 4476 | func = _perf_event_disable; |
79f14641 | 4477 | break; |
cdd6c482 | 4478 | case PERF_EVENT_IOC_RESET: |
f63a8daa | 4479 | func = _perf_event_reset; |
6de6a7b9 | 4480 | break; |
3df5edad | 4481 | |
cdd6c482 | 4482 | case PERF_EVENT_IOC_REFRESH: |
f63a8daa | 4483 | return _perf_event_refresh(event, arg); |
08247e31 | 4484 | |
cdd6c482 IM |
4485 | case PERF_EVENT_IOC_PERIOD: |
4486 | return perf_event_period(event, (u64 __user *)arg); | |
08247e31 | 4487 | |
cf4957f1 JO |
4488 | case PERF_EVENT_IOC_ID: |
4489 | { | |
4490 | u64 id = primary_event_id(event); | |
4491 | ||
4492 | if (copy_to_user((void __user *)arg, &id, sizeof(id))) | |
4493 | return -EFAULT; | |
4494 | return 0; | |
4495 | } | |
4496 | ||
cdd6c482 | 4497 | case PERF_EVENT_IOC_SET_OUTPUT: |
ac9721f3 | 4498 | { |
ac9721f3 | 4499 | int ret; |
ac9721f3 | 4500 | if (arg != -1) { |
2903ff01 AV |
4501 | struct perf_event *output_event; |
4502 | struct fd output; | |
4503 | ret = perf_fget_light(arg, &output); | |
4504 | if (ret) | |
4505 | return ret; | |
4506 | output_event = output.file->private_data; | |
4507 | ret = perf_event_set_output(event, output_event); | |
4508 | fdput(output); | |
4509 | } else { | |
4510 | ret = perf_event_set_output(event, NULL); | |
ac9721f3 | 4511 | } |
ac9721f3 PZ |
4512 | return ret; |
4513 | } | |
a4be7c27 | 4514 | |
6fb2915d LZ |
4515 | case PERF_EVENT_IOC_SET_FILTER: |
4516 | return perf_event_set_filter(event, (void __user *)arg); | |
4517 | ||
2541517c AS |
4518 | case PERF_EVENT_IOC_SET_BPF: |
4519 | return perf_event_set_bpf_prog(event, arg); | |
4520 | ||
86e7972f WN |
4521 | case PERF_EVENT_IOC_PAUSE_OUTPUT: { |
4522 | struct ring_buffer *rb; | |
4523 | ||
4524 | rcu_read_lock(); | |
4525 | rb = rcu_dereference(event->rb); | |
4526 | if (!rb || !rb->nr_pages) { | |
4527 | rcu_read_unlock(); | |
4528 | return -EINVAL; | |
4529 | } | |
4530 | rb_toggle_paused(rb, !!arg); | |
4531 | rcu_read_unlock(); | |
4532 | return 0; | |
4533 | } | |
d859e29f | 4534 | default: |
3df5edad | 4535 | return -ENOTTY; |
d859e29f | 4536 | } |
3df5edad PZ |
4537 | |
4538 | if (flags & PERF_IOC_FLAG_GROUP) | |
cdd6c482 | 4539 | perf_event_for_each(event, func); |
3df5edad | 4540 | else |
cdd6c482 | 4541 | perf_event_for_each_child(event, func); |
3df5edad PZ |
4542 | |
4543 | return 0; | |
d859e29f PM |
4544 | } |
4545 | ||
f63a8daa PZ |
4546 | static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
4547 | { | |
4548 | struct perf_event *event = file->private_data; | |
4549 | struct perf_event_context *ctx; | |
4550 | long ret; | |
4551 | ||
4552 | ctx = perf_event_ctx_lock(event); | |
4553 | ret = _perf_ioctl(event, cmd, arg); | |
4554 | perf_event_ctx_unlock(event, ctx); | |
4555 | ||
4556 | return ret; | |
4557 | } | |
4558 | ||
b3f20785 PM |
4559 | #ifdef CONFIG_COMPAT |
4560 | static long perf_compat_ioctl(struct file *file, unsigned int cmd, | |
4561 | unsigned long arg) | |
4562 | { | |
4563 | switch (_IOC_NR(cmd)) { | |
4564 | case _IOC_NR(PERF_EVENT_IOC_SET_FILTER): | |
4565 | case _IOC_NR(PERF_EVENT_IOC_ID): | |
4566 | /* Fix up pointer size (usually 4 -> 8 in 32-on-64-bit case */ | |
4567 | if (_IOC_SIZE(cmd) == sizeof(compat_uptr_t)) { | |
4568 | cmd &= ~IOCSIZE_MASK; | |
4569 | cmd |= sizeof(void *) << IOCSIZE_SHIFT; | |
4570 | } | |
4571 | break; | |
4572 | } | |
4573 | return perf_ioctl(file, cmd, arg); | |
4574 | } | |
4575 | #else | |
4576 | # define perf_compat_ioctl NULL | |
4577 | #endif | |
4578 | ||
cdd6c482 | 4579 | int perf_event_task_enable(void) |
771d7cde | 4580 | { |
f63a8daa | 4581 | struct perf_event_context *ctx; |
cdd6c482 | 4582 | struct perf_event *event; |
771d7cde | 4583 | |
cdd6c482 | 4584 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
4585 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
4586 | ctx = perf_event_ctx_lock(event); | |
4587 | perf_event_for_each_child(event, _perf_event_enable); | |
4588 | perf_event_ctx_unlock(event, ctx); | |
4589 | } | |
cdd6c482 | 4590 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
4591 | |
4592 | return 0; | |
4593 | } | |
4594 | ||
cdd6c482 | 4595 | int perf_event_task_disable(void) |
771d7cde | 4596 | { |
f63a8daa | 4597 | struct perf_event_context *ctx; |
cdd6c482 | 4598 | struct perf_event *event; |
771d7cde | 4599 | |
cdd6c482 | 4600 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
4601 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
4602 | ctx = perf_event_ctx_lock(event); | |
4603 | perf_event_for_each_child(event, _perf_event_disable); | |
4604 | perf_event_ctx_unlock(event, ctx); | |
4605 | } | |
cdd6c482 | 4606 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
4607 | |
4608 | return 0; | |
4609 | } | |
4610 | ||
cdd6c482 | 4611 | static int perf_event_index(struct perf_event *event) |
194002b2 | 4612 | { |
a4eaf7f1 PZ |
4613 | if (event->hw.state & PERF_HES_STOPPED) |
4614 | return 0; | |
4615 | ||
cdd6c482 | 4616 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
194002b2 PZ |
4617 | return 0; |
4618 | ||
35edc2a5 | 4619 | return event->pmu->event_idx(event); |
194002b2 PZ |
4620 | } |
4621 | ||
c4794295 | 4622 | static void calc_timer_values(struct perf_event *event, |
e3f3541c | 4623 | u64 *now, |
7f310a5d EM |
4624 | u64 *enabled, |
4625 | u64 *running) | |
c4794295 | 4626 | { |
e3f3541c | 4627 | u64 ctx_time; |
c4794295 | 4628 | |
e3f3541c PZ |
4629 | *now = perf_clock(); |
4630 | ctx_time = event->shadow_ctx_time + *now; | |
c4794295 EM |
4631 | *enabled = ctx_time - event->tstamp_enabled; |
4632 | *running = ctx_time - event->tstamp_running; | |
4633 | } | |
4634 | ||
fa731587 PZ |
4635 | static void perf_event_init_userpage(struct perf_event *event) |
4636 | { | |
4637 | struct perf_event_mmap_page *userpg; | |
4638 | struct ring_buffer *rb; | |
4639 | ||
4640 | rcu_read_lock(); | |
4641 | rb = rcu_dereference(event->rb); | |
4642 | if (!rb) | |
4643 | goto unlock; | |
4644 | ||
4645 | userpg = rb->user_page; | |
4646 | ||
4647 | /* Allow new userspace to detect that bit 0 is deprecated */ | |
4648 | userpg->cap_bit0_is_deprecated = 1; | |
4649 | userpg->size = offsetof(struct perf_event_mmap_page, __reserved); | |
e8c6deac AS |
4650 | userpg->data_offset = PAGE_SIZE; |
4651 | userpg->data_size = perf_data_size(rb); | |
fa731587 PZ |
4652 | |
4653 | unlock: | |
4654 | rcu_read_unlock(); | |
4655 | } | |
4656 | ||
c1317ec2 AL |
4657 | void __weak arch_perf_update_userpage( |
4658 | struct perf_event *event, struct perf_event_mmap_page *userpg, u64 now) | |
e3f3541c PZ |
4659 | { |
4660 | } | |
4661 | ||
38ff667b PZ |
4662 | /* |
4663 | * Callers need to ensure there can be no nesting of this function, otherwise | |
4664 | * the seqlock logic goes bad. We can not serialize this because the arch | |
4665 | * code calls this from NMI context. | |
4666 | */ | |
cdd6c482 | 4667 | void perf_event_update_userpage(struct perf_event *event) |
37d81828 | 4668 | { |
cdd6c482 | 4669 | struct perf_event_mmap_page *userpg; |
76369139 | 4670 | struct ring_buffer *rb; |
e3f3541c | 4671 | u64 enabled, running, now; |
38ff667b PZ |
4672 | |
4673 | rcu_read_lock(); | |
5ec4c599 PZ |
4674 | rb = rcu_dereference(event->rb); |
4675 | if (!rb) | |
4676 | goto unlock; | |
4677 | ||
0d641208 EM |
4678 | /* |
4679 | * compute total_time_enabled, total_time_running | |
4680 | * based on snapshot values taken when the event | |
4681 | * was last scheduled in. | |
4682 | * | |
4683 | * we cannot simply called update_context_time() | |
4684 | * because of locking issue as we can be called in | |
4685 | * NMI context | |
4686 | */ | |
e3f3541c | 4687 | calc_timer_values(event, &now, &enabled, &running); |
38ff667b | 4688 | |
76369139 | 4689 | userpg = rb->user_page; |
7b732a75 PZ |
4690 | /* |
4691 | * Disable preemption so as to not let the corresponding user-space | |
4692 | * spin too long if we get preempted. | |
4693 | */ | |
4694 | preempt_disable(); | |
37d81828 | 4695 | ++userpg->lock; |
92f22a38 | 4696 | barrier(); |
cdd6c482 | 4697 | userpg->index = perf_event_index(event); |
b5e58793 | 4698 | userpg->offset = perf_event_count(event); |
365a4038 | 4699 | if (userpg->index) |
e7850595 | 4700 | userpg->offset -= local64_read(&event->hw.prev_count); |
7b732a75 | 4701 | |
0d641208 | 4702 | userpg->time_enabled = enabled + |
cdd6c482 | 4703 | atomic64_read(&event->child_total_time_enabled); |
7f8b4e4e | 4704 | |
0d641208 | 4705 | userpg->time_running = running + |
cdd6c482 | 4706 | atomic64_read(&event->child_total_time_running); |
7f8b4e4e | 4707 | |
c1317ec2 | 4708 | arch_perf_update_userpage(event, userpg, now); |
e3f3541c | 4709 | |
92f22a38 | 4710 | barrier(); |
37d81828 | 4711 | ++userpg->lock; |
7b732a75 | 4712 | preempt_enable(); |
38ff667b | 4713 | unlock: |
7b732a75 | 4714 | rcu_read_unlock(); |
37d81828 PM |
4715 | } |
4716 | ||
906010b2 PZ |
4717 | static int perf_mmap_fault(struct vm_area_struct *vma, struct vm_fault *vmf) |
4718 | { | |
4719 | struct perf_event *event = vma->vm_file->private_data; | |
76369139 | 4720 | struct ring_buffer *rb; |
906010b2 PZ |
4721 | int ret = VM_FAULT_SIGBUS; |
4722 | ||
4723 | if (vmf->flags & FAULT_FLAG_MKWRITE) { | |
4724 | if (vmf->pgoff == 0) | |
4725 | ret = 0; | |
4726 | return ret; | |
4727 | } | |
4728 | ||
4729 | rcu_read_lock(); | |
76369139 FW |
4730 | rb = rcu_dereference(event->rb); |
4731 | if (!rb) | |
906010b2 PZ |
4732 | goto unlock; |
4733 | ||
4734 | if (vmf->pgoff && (vmf->flags & FAULT_FLAG_WRITE)) | |
4735 | goto unlock; | |
4736 | ||
76369139 | 4737 | vmf->page = perf_mmap_to_page(rb, vmf->pgoff); |
906010b2 PZ |
4738 | if (!vmf->page) |
4739 | goto unlock; | |
4740 | ||
4741 | get_page(vmf->page); | |
4742 | vmf->page->mapping = vma->vm_file->f_mapping; | |
4743 | vmf->page->index = vmf->pgoff; | |
4744 | ||
4745 | ret = 0; | |
4746 | unlock: | |
4747 | rcu_read_unlock(); | |
4748 | ||
4749 | return ret; | |
4750 | } | |
4751 | ||
10c6db11 PZ |
4752 | static void ring_buffer_attach(struct perf_event *event, |
4753 | struct ring_buffer *rb) | |
4754 | { | |
b69cf536 | 4755 | struct ring_buffer *old_rb = NULL; |
10c6db11 PZ |
4756 | unsigned long flags; |
4757 | ||
b69cf536 PZ |
4758 | if (event->rb) { |
4759 | /* | |
4760 | * Should be impossible, we set this when removing | |
4761 | * event->rb_entry and wait/clear when adding event->rb_entry. | |
4762 | */ | |
4763 | WARN_ON_ONCE(event->rcu_pending); | |
10c6db11 | 4764 | |
b69cf536 | 4765 | old_rb = event->rb; |
b69cf536 PZ |
4766 | spin_lock_irqsave(&old_rb->event_lock, flags); |
4767 | list_del_rcu(&event->rb_entry); | |
4768 | spin_unlock_irqrestore(&old_rb->event_lock, flags); | |
10c6db11 | 4769 | |
2f993cf0 ON |
4770 | event->rcu_batches = get_state_synchronize_rcu(); |
4771 | event->rcu_pending = 1; | |
b69cf536 | 4772 | } |
10c6db11 | 4773 | |
b69cf536 | 4774 | if (rb) { |
2f993cf0 ON |
4775 | if (event->rcu_pending) { |
4776 | cond_synchronize_rcu(event->rcu_batches); | |
4777 | event->rcu_pending = 0; | |
4778 | } | |
4779 | ||
b69cf536 PZ |
4780 | spin_lock_irqsave(&rb->event_lock, flags); |
4781 | list_add_rcu(&event->rb_entry, &rb->event_list); | |
4782 | spin_unlock_irqrestore(&rb->event_lock, flags); | |
4783 | } | |
4784 | ||
4785 | rcu_assign_pointer(event->rb, rb); | |
4786 | ||
4787 | if (old_rb) { | |
4788 | ring_buffer_put(old_rb); | |
4789 | /* | |
4790 | * Since we detached before setting the new rb, so that we | |
4791 | * could attach the new rb, we could have missed a wakeup. | |
4792 | * Provide it now. | |
4793 | */ | |
4794 | wake_up_all(&event->waitq); | |
4795 | } | |
10c6db11 PZ |
4796 | } |
4797 | ||
4798 | static void ring_buffer_wakeup(struct perf_event *event) | |
4799 | { | |
4800 | struct ring_buffer *rb; | |
4801 | ||
4802 | rcu_read_lock(); | |
4803 | rb = rcu_dereference(event->rb); | |
9bb5d40c PZ |
4804 | if (rb) { |
4805 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) | |
4806 | wake_up_all(&event->waitq); | |
4807 | } | |
10c6db11 PZ |
4808 | rcu_read_unlock(); |
4809 | } | |
4810 | ||
fdc26706 | 4811 | struct ring_buffer *ring_buffer_get(struct perf_event *event) |
7b732a75 | 4812 | { |
76369139 | 4813 | struct ring_buffer *rb; |
7b732a75 | 4814 | |
ac9721f3 | 4815 | rcu_read_lock(); |
76369139 FW |
4816 | rb = rcu_dereference(event->rb); |
4817 | if (rb) { | |
4818 | if (!atomic_inc_not_zero(&rb->refcount)) | |
4819 | rb = NULL; | |
ac9721f3 PZ |
4820 | } |
4821 | rcu_read_unlock(); | |
4822 | ||
76369139 | 4823 | return rb; |
ac9721f3 PZ |
4824 | } |
4825 | ||
fdc26706 | 4826 | void ring_buffer_put(struct ring_buffer *rb) |
ac9721f3 | 4827 | { |
76369139 | 4828 | if (!atomic_dec_and_test(&rb->refcount)) |
ac9721f3 | 4829 | return; |
7b732a75 | 4830 | |
9bb5d40c | 4831 | WARN_ON_ONCE(!list_empty(&rb->event_list)); |
10c6db11 | 4832 | |
76369139 | 4833 | call_rcu(&rb->rcu_head, rb_free_rcu); |
7b732a75 PZ |
4834 | } |
4835 | ||
4836 | static void perf_mmap_open(struct vm_area_struct *vma) | |
4837 | { | |
cdd6c482 | 4838 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 4839 | |
cdd6c482 | 4840 | atomic_inc(&event->mmap_count); |
9bb5d40c | 4841 | atomic_inc(&event->rb->mmap_count); |
1e0fb9ec | 4842 | |
45bfb2e5 PZ |
4843 | if (vma->vm_pgoff) |
4844 | atomic_inc(&event->rb->aux_mmap_count); | |
4845 | ||
1e0fb9ec AL |
4846 | if (event->pmu->event_mapped) |
4847 | event->pmu->event_mapped(event); | |
7b732a75 PZ |
4848 | } |
4849 | ||
95ff4ca2 AS |
4850 | static void perf_pmu_output_stop(struct perf_event *event); |
4851 | ||
9bb5d40c PZ |
4852 | /* |
4853 | * A buffer can be mmap()ed multiple times; either directly through the same | |
4854 | * event, or through other events by use of perf_event_set_output(). | |
4855 | * | |
4856 | * In order to undo the VM accounting done by perf_mmap() we need to destroy | |
4857 | * the buffer here, where we still have a VM context. This means we need | |
4858 | * to detach all events redirecting to us. | |
4859 | */ | |
7b732a75 PZ |
4860 | static void perf_mmap_close(struct vm_area_struct *vma) |
4861 | { | |
cdd6c482 | 4862 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 4863 | |
b69cf536 | 4864 | struct ring_buffer *rb = ring_buffer_get(event); |
9bb5d40c PZ |
4865 | struct user_struct *mmap_user = rb->mmap_user; |
4866 | int mmap_locked = rb->mmap_locked; | |
4867 | unsigned long size = perf_data_size(rb); | |
789f90fc | 4868 | |
1e0fb9ec AL |
4869 | if (event->pmu->event_unmapped) |
4870 | event->pmu->event_unmapped(event); | |
4871 | ||
45bfb2e5 PZ |
4872 | /* |
4873 | * rb->aux_mmap_count will always drop before rb->mmap_count and | |
4874 | * event->mmap_count, so it is ok to use event->mmap_mutex to | |
4875 | * serialize with perf_mmap here. | |
4876 | */ | |
4877 | if (rb_has_aux(rb) && vma->vm_pgoff == rb->aux_pgoff && | |
4878 | atomic_dec_and_mutex_lock(&rb->aux_mmap_count, &event->mmap_mutex)) { | |
95ff4ca2 AS |
4879 | /* |
4880 | * Stop all AUX events that are writing to this buffer, | |
4881 | * so that we can free its AUX pages and corresponding PMU | |
4882 | * data. Note that after rb::aux_mmap_count dropped to zero, | |
4883 | * they won't start any more (see perf_aux_output_begin()). | |
4884 | */ | |
4885 | perf_pmu_output_stop(event); | |
4886 | ||
4887 | /* now it's safe to free the pages */ | |
45bfb2e5 PZ |
4888 | atomic_long_sub(rb->aux_nr_pages, &mmap_user->locked_vm); |
4889 | vma->vm_mm->pinned_vm -= rb->aux_mmap_locked; | |
4890 | ||
95ff4ca2 | 4891 | /* this has to be the last one */ |
45bfb2e5 | 4892 | rb_free_aux(rb); |
95ff4ca2 AS |
4893 | WARN_ON_ONCE(atomic_read(&rb->aux_refcount)); |
4894 | ||
45bfb2e5 PZ |
4895 | mutex_unlock(&event->mmap_mutex); |
4896 | } | |
4897 | ||
9bb5d40c PZ |
4898 | atomic_dec(&rb->mmap_count); |
4899 | ||
4900 | if (!atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex)) | |
b69cf536 | 4901 | goto out_put; |
9bb5d40c | 4902 | |
b69cf536 | 4903 | ring_buffer_attach(event, NULL); |
9bb5d40c PZ |
4904 | mutex_unlock(&event->mmap_mutex); |
4905 | ||
4906 | /* If there's still other mmap()s of this buffer, we're done. */ | |
b69cf536 PZ |
4907 | if (atomic_read(&rb->mmap_count)) |
4908 | goto out_put; | |
ac9721f3 | 4909 | |
9bb5d40c PZ |
4910 | /* |
4911 | * No other mmap()s, detach from all other events that might redirect | |
4912 | * into the now unreachable buffer. Somewhat complicated by the | |
4913 | * fact that rb::event_lock otherwise nests inside mmap_mutex. | |
4914 | */ | |
4915 | again: | |
4916 | rcu_read_lock(); | |
4917 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) { | |
4918 | if (!atomic_long_inc_not_zero(&event->refcount)) { | |
4919 | /* | |
4920 | * This event is en-route to free_event() which will | |
4921 | * detach it and remove it from the list. | |
4922 | */ | |
4923 | continue; | |
4924 | } | |
4925 | rcu_read_unlock(); | |
789f90fc | 4926 | |
9bb5d40c PZ |
4927 | mutex_lock(&event->mmap_mutex); |
4928 | /* | |
4929 | * Check we didn't race with perf_event_set_output() which can | |
4930 | * swizzle the rb from under us while we were waiting to | |
4931 | * acquire mmap_mutex. | |
4932 | * | |
4933 | * If we find a different rb; ignore this event, a next | |
4934 | * iteration will no longer find it on the list. We have to | |
4935 | * still restart the iteration to make sure we're not now | |
4936 | * iterating the wrong list. | |
4937 | */ | |
b69cf536 PZ |
4938 | if (event->rb == rb) |
4939 | ring_buffer_attach(event, NULL); | |
4940 | ||
cdd6c482 | 4941 | mutex_unlock(&event->mmap_mutex); |
9bb5d40c | 4942 | put_event(event); |
ac9721f3 | 4943 | |
9bb5d40c PZ |
4944 | /* |
4945 | * Restart the iteration; either we're on the wrong list or | |
4946 | * destroyed its integrity by doing a deletion. | |
4947 | */ | |
4948 | goto again; | |
7b732a75 | 4949 | } |
9bb5d40c PZ |
4950 | rcu_read_unlock(); |
4951 | ||
4952 | /* | |
4953 | * It could be there's still a few 0-ref events on the list; they'll | |
4954 | * get cleaned up by free_event() -- they'll also still have their | |
4955 | * ref on the rb and will free it whenever they are done with it. | |
4956 | * | |
4957 | * Aside from that, this buffer is 'fully' detached and unmapped, | |
4958 | * undo the VM accounting. | |
4959 | */ | |
4960 | ||
4961 | atomic_long_sub((size >> PAGE_SHIFT) + 1, &mmap_user->locked_vm); | |
4962 | vma->vm_mm->pinned_vm -= mmap_locked; | |
4963 | free_uid(mmap_user); | |
4964 | ||
b69cf536 | 4965 | out_put: |
9bb5d40c | 4966 | ring_buffer_put(rb); /* could be last */ |
37d81828 PM |
4967 | } |
4968 | ||
f0f37e2f | 4969 | static const struct vm_operations_struct perf_mmap_vmops = { |
43a21ea8 | 4970 | .open = perf_mmap_open, |
45bfb2e5 | 4971 | .close = perf_mmap_close, /* non mergable */ |
43a21ea8 PZ |
4972 | .fault = perf_mmap_fault, |
4973 | .page_mkwrite = perf_mmap_fault, | |
37d81828 PM |
4974 | }; |
4975 | ||
4976 | static int perf_mmap(struct file *file, struct vm_area_struct *vma) | |
4977 | { | |
cdd6c482 | 4978 | struct perf_event *event = file->private_data; |
22a4f650 | 4979 | unsigned long user_locked, user_lock_limit; |
789f90fc | 4980 | struct user_struct *user = current_user(); |
22a4f650 | 4981 | unsigned long locked, lock_limit; |
45bfb2e5 | 4982 | struct ring_buffer *rb = NULL; |
7b732a75 PZ |
4983 | unsigned long vma_size; |
4984 | unsigned long nr_pages; | |
45bfb2e5 | 4985 | long user_extra = 0, extra = 0; |
d57e34fd | 4986 | int ret = 0, flags = 0; |
37d81828 | 4987 | |
c7920614 PZ |
4988 | /* |
4989 | * Don't allow mmap() of inherited per-task counters. This would | |
4990 | * create a performance issue due to all children writing to the | |
76369139 | 4991 | * same rb. |
c7920614 PZ |
4992 | */ |
4993 | if (event->cpu == -1 && event->attr.inherit) | |
4994 | return -EINVAL; | |
4995 | ||
43a21ea8 | 4996 | if (!(vma->vm_flags & VM_SHARED)) |
37d81828 | 4997 | return -EINVAL; |
7b732a75 PZ |
4998 | |
4999 | vma_size = vma->vm_end - vma->vm_start; | |
45bfb2e5 PZ |
5000 | |
5001 | if (vma->vm_pgoff == 0) { | |
5002 | nr_pages = (vma_size / PAGE_SIZE) - 1; | |
5003 | } else { | |
5004 | /* | |
5005 | * AUX area mapping: if rb->aux_nr_pages != 0, it's already | |
5006 | * mapped, all subsequent mappings should have the same size | |
5007 | * and offset. Must be above the normal perf buffer. | |
5008 | */ | |
5009 | u64 aux_offset, aux_size; | |
5010 | ||
5011 | if (!event->rb) | |
5012 | return -EINVAL; | |
5013 | ||
5014 | nr_pages = vma_size / PAGE_SIZE; | |
5015 | ||
5016 | mutex_lock(&event->mmap_mutex); | |
5017 | ret = -EINVAL; | |
5018 | ||
5019 | rb = event->rb; | |
5020 | if (!rb) | |
5021 | goto aux_unlock; | |
5022 | ||
5023 | aux_offset = ACCESS_ONCE(rb->user_page->aux_offset); | |
5024 | aux_size = ACCESS_ONCE(rb->user_page->aux_size); | |
5025 | ||
5026 | if (aux_offset < perf_data_size(rb) + PAGE_SIZE) | |
5027 | goto aux_unlock; | |
5028 | ||
5029 | if (aux_offset != vma->vm_pgoff << PAGE_SHIFT) | |
5030 | goto aux_unlock; | |
5031 | ||
5032 | /* already mapped with a different offset */ | |
5033 | if (rb_has_aux(rb) && rb->aux_pgoff != vma->vm_pgoff) | |
5034 | goto aux_unlock; | |
5035 | ||
5036 | if (aux_size != vma_size || aux_size != nr_pages * PAGE_SIZE) | |
5037 | goto aux_unlock; | |
5038 | ||
5039 | /* already mapped with a different size */ | |
5040 | if (rb_has_aux(rb) && rb->aux_nr_pages != nr_pages) | |
5041 | goto aux_unlock; | |
5042 | ||
5043 | if (!is_power_of_2(nr_pages)) | |
5044 | goto aux_unlock; | |
5045 | ||
5046 | if (!atomic_inc_not_zero(&rb->mmap_count)) | |
5047 | goto aux_unlock; | |
5048 | ||
5049 | if (rb_has_aux(rb)) { | |
5050 | atomic_inc(&rb->aux_mmap_count); | |
5051 | ret = 0; | |
5052 | goto unlock; | |
5053 | } | |
5054 | ||
5055 | atomic_set(&rb->aux_mmap_count, 1); | |
5056 | user_extra = nr_pages; | |
5057 | ||
5058 | goto accounting; | |
5059 | } | |
7b732a75 | 5060 | |
7730d865 | 5061 | /* |
76369139 | 5062 | * If we have rb pages ensure they're a power-of-two number, so we |
7730d865 PZ |
5063 | * can do bitmasks instead of modulo. |
5064 | */ | |
2ed11312 | 5065 | if (nr_pages != 0 && !is_power_of_2(nr_pages)) |
37d81828 PM |
5066 | return -EINVAL; |
5067 | ||
7b732a75 | 5068 | if (vma_size != PAGE_SIZE * (1 + nr_pages)) |
37d81828 PM |
5069 | return -EINVAL; |
5070 | ||
cdd6c482 | 5071 | WARN_ON_ONCE(event->ctx->parent_ctx); |
9bb5d40c | 5072 | again: |
cdd6c482 | 5073 | mutex_lock(&event->mmap_mutex); |
76369139 | 5074 | if (event->rb) { |
9bb5d40c | 5075 | if (event->rb->nr_pages != nr_pages) { |
ebb3c4c4 | 5076 | ret = -EINVAL; |
9bb5d40c PZ |
5077 | goto unlock; |
5078 | } | |
5079 | ||
5080 | if (!atomic_inc_not_zero(&event->rb->mmap_count)) { | |
5081 | /* | |
5082 | * Raced against perf_mmap_close() through | |
5083 | * perf_event_set_output(). Try again, hope for better | |
5084 | * luck. | |
5085 | */ | |
5086 | mutex_unlock(&event->mmap_mutex); | |
5087 | goto again; | |
5088 | } | |
5089 | ||
ebb3c4c4 PZ |
5090 | goto unlock; |
5091 | } | |
5092 | ||
789f90fc | 5093 | user_extra = nr_pages + 1; |
45bfb2e5 PZ |
5094 | |
5095 | accounting: | |
cdd6c482 | 5096 | user_lock_limit = sysctl_perf_event_mlock >> (PAGE_SHIFT - 10); |
a3862d3f IM |
5097 | |
5098 | /* | |
5099 | * Increase the limit linearly with more CPUs: | |
5100 | */ | |
5101 | user_lock_limit *= num_online_cpus(); | |
5102 | ||
789f90fc | 5103 | user_locked = atomic_long_read(&user->locked_vm) + user_extra; |
c5078f78 | 5104 | |
789f90fc PZ |
5105 | if (user_locked > user_lock_limit) |
5106 | extra = user_locked - user_lock_limit; | |
7b732a75 | 5107 | |
78d7d407 | 5108 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
7b732a75 | 5109 | lock_limit >>= PAGE_SHIFT; |
bc3e53f6 | 5110 | locked = vma->vm_mm->pinned_vm + extra; |
7b732a75 | 5111 | |
459ec28a IM |
5112 | if ((locked > lock_limit) && perf_paranoid_tracepoint_raw() && |
5113 | !capable(CAP_IPC_LOCK)) { | |
ebb3c4c4 PZ |
5114 | ret = -EPERM; |
5115 | goto unlock; | |
5116 | } | |
7b732a75 | 5117 | |
45bfb2e5 | 5118 | WARN_ON(!rb && event->rb); |
906010b2 | 5119 | |
d57e34fd | 5120 | if (vma->vm_flags & VM_WRITE) |
76369139 | 5121 | flags |= RING_BUFFER_WRITABLE; |
d57e34fd | 5122 | |
76369139 | 5123 | if (!rb) { |
45bfb2e5 PZ |
5124 | rb = rb_alloc(nr_pages, |
5125 | event->attr.watermark ? event->attr.wakeup_watermark : 0, | |
5126 | event->cpu, flags); | |
26cb63ad | 5127 | |
45bfb2e5 PZ |
5128 | if (!rb) { |
5129 | ret = -ENOMEM; | |
5130 | goto unlock; | |
5131 | } | |
43a21ea8 | 5132 | |
45bfb2e5 PZ |
5133 | atomic_set(&rb->mmap_count, 1); |
5134 | rb->mmap_user = get_current_user(); | |
5135 | rb->mmap_locked = extra; | |
26cb63ad | 5136 | |
45bfb2e5 | 5137 | ring_buffer_attach(event, rb); |
ac9721f3 | 5138 | |
45bfb2e5 PZ |
5139 | perf_event_init_userpage(event); |
5140 | perf_event_update_userpage(event); | |
5141 | } else { | |
1a594131 AS |
5142 | ret = rb_alloc_aux(rb, event, vma->vm_pgoff, nr_pages, |
5143 | event->attr.aux_watermark, flags); | |
45bfb2e5 PZ |
5144 | if (!ret) |
5145 | rb->aux_mmap_locked = extra; | |
5146 | } | |
9a0f05cb | 5147 | |
ebb3c4c4 | 5148 | unlock: |
45bfb2e5 PZ |
5149 | if (!ret) { |
5150 | atomic_long_add(user_extra, &user->locked_vm); | |
5151 | vma->vm_mm->pinned_vm += extra; | |
5152 | ||
ac9721f3 | 5153 | atomic_inc(&event->mmap_count); |
45bfb2e5 PZ |
5154 | } else if (rb) { |
5155 | atomic_dec(&rb->mmap_count); | |
5156 | } | |
5157 | aux_unlock: | |
cdd6c482 | 5158 | mutex_unlock(&event->mmap_mutex); |
37d81828 | 5159 | |
9bb5d40c PZ |
5160 | /* |
5161 | * Since pinned accounting is per vm we cannot allow fork() to copy our | |
5162 | * vma. | |
5163 | */ | |
26cb63ad | 5164 | vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND | VM_DONTDUMP; |
37d81828 | 5165 | vma->vm_ops = &perf_mmap_vmops; |
7b732a75 | 5166 | |
1e0fb9ec AL |
5167 | if (event->pmu->event_mapped) |
5168 | event->pmu->event_mapped(event); | |
5169 | ||
7b732a75 | 5170 | return ret; |
37d81828 PM |
5171 | } |
5172 | ||
3c446b3d PZ |
5173 | static int perf_fasync(int fd, struct file *filp, int on) |
5174 | { | |
496ad9aa | 5175 | struct inode *inode = file_inode(filp); |
cdd6c482 | 5176 | struct perf_event *event = filp->private_data; |
3c446b3d PZ |
5177 | int retval; |
5178 | ||
5955102c | 5179 | inode_lock(inode); |
cdd6c482 | 5180 | retval = fasync_helper(fd, filp, on, &event->fasync); |
5955102c | 5181 | inode_unlock(inode); |
3c446b3d PZ |
5182 | |
5183 | if (retval < 0) | |
5184 | return retval; | |
5185 | ||
5186 | return 0; | |
5187 | } | |
5188 | ||
0793a61d | 5189 | static const struct file_operations perf_fops = { |
3326c1ce | 5190 | .llseek = no_llseek, |
0793a61d TG |
5191 | .release = perf_release, |
5192 | .read = perf_read, | |
5193 | .poll = perf_poll, | |
d859e29f | 5194 | .unlocked_ioctl = perf_ioctl, |
b3f20785 | 5195 | .compat_ioctl = perf_compat_ioctl, |
37d81828 | 5196 | .mmap = perf_mmap, |
3c446b3d | 5197 | .fasync = perf_fasync, |
0793a61d TG |
5198 | }; |
5199 | ||
925d519a | 5200 | /* |
cdd6c482 | 5201 | * Perf event wakeup |
925d519a PZ |
5202 | * |
5203 | * If there's data, ensure we set the poll() state and publish everything | |
5204 | * to user-space before waking everybody up. | |
5205 | */ | |
5206 | ||
fed66e2c PZ |
5207 | static inline struct fasync_struct **perf_event_fasync(struct perf_event *event) |
5208 | { | |
5209 | /* only the parent has fasync state */ | |
5210 | if (event->parent) | |
5211 | event = event->parent; | |
5212 | return &event->fasync; | |
5213 | } | |
5214 | ||
cdd6c482 | 5215 | void perf_event_wakeup(struct perf_event *event) |
925d519a | 5216 | { |
10c6db11 | 5217 | ring_buffer_wakeup(event); |
4c9e2542 | 5218 | |
cdd6c482 | 5219 | if (event->pending_kill) { |
fed66e2c | 5220 | kill_fasync(perf_event_fasync(event), SIGIO, event->pending_kill); |
cdd6c482 | 5221 | event->pending_kill = 0; |
4c9e2542 | 5222 | } |
925d519a PZ |
5223 | } |
5224 | ||
e360adbe | 5225 | static void perf_pending_event(struct irq_work *entry) |
79f14641 | 5226 | { |
cdd6c482 IM |
5227 | struct perf_event *event = container_of(entry, |
5228 | struct perf_event, pending); | |
d525211f PZ |
5229 | int rctx; |
5230 | ||
5231 | rctx = perf_swevent_get_recursion_context(); | |
5232 | /* | |
5233 | * If we 'fail' here, that's OK, it means recursion is already disabled | |
5234 | * and we won't recurse 'further'. | |
5235 | */ | |
79f14641 | 5236 | |
cdd6c482 IM |
5237 | if (event->pending_disable) { |
5238 | event->pending_disable = 0; | |
fae3fde6 | 5239 | perf_event_disable_local(event); |
79f14641 PZ |
5240 | } |
5241 | ||
cdd6c482 IM |
5242 | if (event->pending_wakeup) { |
5243 | event->pending_wakeup = 0; | |
5244 | perf_event_wakeup(event); | |
79f14641 | 5245 | } |
d525211f PZ |
5246 | |
5247 | if (rctx >= 0) | |
5248 | perf_swevent_put_recursion_context(rctx); | |
79f14641 PZ |
5249 | } |
5250 | ||
39447b38 ZY |
5251 | /* |
5252 | * We assume there is only KVM supporting the callbacks. | |
5253 | * Later on, we might change it to a list if there is | |
5254 | * another virtualization implementation supporting the callbacks. | |
5255 | */ | |
5256 | struct perf_guest_info_callbacks *perf_guest_cbs; | |
5257 | ||
5258 | int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
5259 | { | |
5260 | perf_guest_cbs = cbs; | |
5261 | return 0; | |
5262 | } | |
5263 | EXPORT_SYMBOL_GPL(perf_register_guest_info_callbacks); | |
5264 | ||
5265 | int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
5266 | { | |
5267 | perf_guest_cbs = NULL; | |
5268 | return 0; | |
5269 | } | |
5270 | EXPORT_SYMBOL_GPL(perf_unregister_guest_info_callbacks); | |
5271 | ||
4018994f JO |
5272 | static void |
5273 | perf_output_sample_regs(struct perf_output_handle *handle, | |
5274 | struct pt_regs *regs, u64 mask) | |
5275 | { | |
5276 | int bit; | |
5277 | ||
5278 | for_each_set_bit(bit, (const unsigned long *) &mask, | |
5279 | sizeof(mask) * BITS_PER_BYTE) { | |
5280 | u64 val; | |
5281 | ||
5282 | val = perf_reg_value(regs, bit); | |
5283 | perf_output_put(handle, val); | |
5284 | } | |
5285 | } | |
5286 | ||
60e2364e | 5287 | static void perf_sample_regs_user(struct perf_regs *regs_user, |
88a7c26a AL |
5288 | struct pt_regs *regs, |
5289 | struct pt_regs *regs_user_copy) | |
4018994f | 5290 | { |
88a7c26a AL |
5291 | if (user_mode(regs)) { |
5292 | regs_user->abi = perf_reg_abi(current); | |
2565711f | 5293 | regs_user->regs = regs; |
88a7c26a AL |
5294 | } else if (current->mm) { |
5295 | perf_get_regs_user(regs_user, regs, regs_user_copy); | |
2565711f PZ |
5296 | } else { |
5297 | regs_user->abi = PERF_SAMPLE_REGS_ABI_NONE; | |
5298 | regs_user->regs = NULL; | |
4018994f JO |
5299 | } |
5300 | } | |
5301 | ||
60e2364e SE |
5302 | static void perf_sample_regs_intr(struct perf_regs *regs_intr, |
5303 | struct pt_regs *regs) | |
5304 | { | |
5305 | regs_intr->regs = regs; | |
5306 | regs_intr->abi = perf_reg_abi(current); | |
5307 | } | |
5308 | ||
5309 | ||
c5ebcedb JO |
5310 | /* |
5311 | * Get remaining task size from user stack pointer. | |
5312 | * | |
5313 | * It'd be better to take stack vma map and limit this more | |
5314 | * precisly, but there's no way to get it safely under interrupt, | |
5315 | * so using TASK_SIZE as limit. | |
5316 | */ | |
5317 | static u64 perf_ustack_task_size(struct pt_regs *regs) | |
5318 | { | |
5319 | unsigned long addr = perf_user_stack_pointer(regs); | |
5320 | ||
5321 | if (!addr || addr >= TASK_SIZE) | |
5322 | return 0; | |
5323 | ||
5324 | return TASK_SIZE - addr; | |
5325 | } | |
5326 | ||
5327 | static u16 | |
5328 | perf_sample_ustack_size(u16 stack_size, u16 header_size, | |
5329 | struct pt_regs *regs) | |
5330 | { | |
5331 | u64 task_size; | |
5332 | ||
5333 | /* No regs, no stack pointer, no dump. */ | |
5334 | if (!regs) | |
5335 | return 0; | |
5336 | ||
5337 | /* | |
5338 | * Check if we fit in with the requested stack size into the: | |
5339 | * - TASK_SIZE | |
5340 | * If we don't, we limit the size to the TASK_SIZE. | |
5341 | * | |
5342 | * - remaining sample size | |
5343 | * If we don't, we customize the stack size to | |
5344 | * fit in to the remaining sample size. | |
5345 | */ | |
5346 | ||
5347 | task_size = min((u64) USHRT_MAX, perf_ustack_task_size(regs)); | |
5348 | stack_size = min(stack_size, (u16) task_size); | |
5349 | ||
5350 | /* Current header size plus static size and dynamic size. */ | |
5351 | header_size += 2 * sizeof(u64); | |
5352 | ||
5353 | /* Do we fit in with the current stack dump size? */ | |
5354 | if ((u16) (header_size + stack_size) < header_size) { | |
5355 | /* | |
5356 | * If we overflow the maximum size for the sample, | |
5357 | * we customize the stack dump size to fit in. | |
5358 | */ | |
5359 | stack_size = USHRT_MAX - header_size - sizeof(u64); | |
5360 | stack_size = round_up(stack_size, sizeof(u64)); | |
5361 | } | |
5362 | ||
5363 | return stack_size; | |
5364 | } | |
5365 | ||
5366 | static void | |
5367 | perf_output_sample_ustack(struct perf_output_handle *handle, u64 dump_size, | |
5368 | struct pt_regs *regs) | |
5369 | { | |
5370 | /* Case of a kernel thread, nothing to dump */ | |
5371 | if (!regs) { | |
5372 | u64 size = 0; | |
5373 | perf_output_put(handle, size); | |
5374 | } else { | |
5375 | unsigned long sp; | |
5376 | unsigned int rem; | |
5377 | u64 dyn_size; | |
5378 | ||
5379 | /* | |
5380 | * We dump: | |
5381 | * static size | |
5382 | * - the size requested by user or the best one we can fit | |
5383 | * in to the sample max size | |
5384 | * data | |
5385 | * - user stack dump data | |
5386 | * dynamic size | |
5387 | * - the actual dumped size | |
5388 | */ | |
5389 | ||
5390 | /* Static size. */ | |
5391 | perf_output_put(handle, dump_size); | |
5392 | ||
5393 | /* Data. */ | |
5394 | sp = perf_user_stack_pointer(regs); | |
5395 | rem = __output_copy_user(handle, (void *) sp, dump_size); | |
5396 | dyn_size = dump_size - rem; | |
5397 | ||
5398 | perf_output_skip(handle, rem); | |
5399 | ||
5400 | /* Dynamic size. */ | |
5401 | perf_output_put(handle, dyn_size); | |
5402 | } | |
5403 | } | |
5404 | ||
c980d109 ACM |
5405 | static void __perf_event_header__init_id(struct perf_event_header *header, |
5406 | struct perf_sample_data *data, | |
5407 | struct perf_event *event) | |
6844c09d ACM |
5408 | { |
5409 | u64 sample_type = event->attr.sample_type; | |
5410 | ||
5411 | data->type = sample_type; | |
5412 | header->size += event->id_header_size; | |
5413 | ||
5414 | if (sample_type & PERF_SAMPLE_TID) { | |
5415 | /* namespace issues */ | |
5416 | data->tid_entry.pid = perf_event_pid(event, current); | |
5417 | data->tid_entry.tid = perf_event_tid(event, current); | |
5418 | } | |
5419 | ||
5420 | if (sample_type & PERF_SAMPLE_TIME) | |
34f43927 | 5421 | data->time = perf_event_clock(event); |
6844c09d | 5422 | |
ff3d527c | 5423 | if (sample_type & (PERF_SAMPLE_ID | PERF_SAMPLE_IDENTIFIER)) |
6844c09d ACM |
5424 | data->id = primary_event_id(event); |
5425 | ||
5426 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
5427 | data->stream_id = event->id; | |
5428 | ||
5429 | if (sample_type & PERF_SAMPLE_CPU) { | |
5430 | data->cpu_entry.cpu = raw_smp_processor_id(); | |
5431 | data->cpu_entry.reserved = 0; | |
5432 | } | |
5433 | } | |
5434 | ||
76369139 FW |
5435 | void perf_event_header__init_id(struct perf_event_header *header, |
5436 | struct perf_sample_data *data, | |
5437 | struct perf_event *event) | |
c980d109 ACM |
5438 | { |
5439 | if (event->attr.sample_id_all) | |
5440 | __perf_event_header__init_id(header, data, event); | |
5441 | } | |
5442 | ||
5443 | static void __perf_event__output_id_sample(struct perf_output_handle *handle, | |
5444 | struct perf_sample_data *data) | |
5445 | { | |
5446 | u64 sample_type = data->type; | |
5447 | ||
5448 | if (sample_type & PERF_SAMPLE_TID) | |
5449 | perf_output_put(handle, data->tid_entry); | |
5450 | ||
5451 | if (sample_type & PERF_SAMPLE_TIME) | |
5452 | perf_output_put(handle, data->time); | |
5453 | ||
5454 | if (sample_type & PERF_SAMPLE_ID) | |
5455 | perf_output_put(handle, data->id); | |
5456 | ||
5457 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
5458 | perf_output_put(handle, data->stream_id); | |
5459 | ||
5460 | if (sample_type & PERF_SAMPLE_CPU) | |
5461 | perf_output_put(handle, data->cpu_entry); | |
ff3d527c AH |
5462 | |
5463 | if (sample_type & PERF_SAMPLE_IDENTIFIER) | |
5464 | perf_output_put(handle, data->id); | |
c980d109 ACM |
5465 | } |
5466 | ||
76369139 FW |
5467 | void perf_event__output_id_sample(struct perf_event *event, |
5468 | struct perf_output_handle *handle, | |
5469 | struct perf_sample_data *sample) | |
c980d109 ACM |
5470 | { |
5471 | if (event->attr.sample_id_all) | |
5472 | __perf_event__output_id_sample(handle, sample); | |
5473 | } | |
5474 | ||
3dab77fb | 5475 | static void perf_output_read_one(struct perf_output_handle *handle, |
eed01528 SE |
5476 | struct perf_event *event, |
5477 | u64 enabled, u64 running) | |
3dab77fb | 5478 | { |
cdd6c482 | 5479 | u64 read_format = event->attr.read_format; |
3dab77fb PZ |
5480 | u64 values[4]; |
5481 | int n = 0; | |
5482 | ||
b5e58793 | 5483 | values[n++] = perf_event_count(event); |
3dab77fb | 5484 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { |
eed01528 | 5485 | values[n++] = enabled + |
cdd6c482 | 5486 | atomic64_read(&event->child_total_time_enabled); |
3dab77fb PZ |
5487 | } |
5488 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { | |
eed01528 | 5489 | values[n++] = running + |
cdd6c482 | 5490 | atomic64_read(&event->child_total_time_running); |
3dab77fb PZ |
5491 | } |
5492 | if (read_format & PERF_FORMAT_ID) | |
cdd6c482 | 5493 | values[n++] = primary_event_id(event); |
3dab77fb | 5494 | |
76369139 | 5495 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
5496 | } |
5497 | ||
5498 | /* | |
cdd6c482 | 5499 | * XXX PERF_FORMAT_GROUP vs inherited events seems difficult. |
3dab77fb PZ |
5500 | */ |
5501 | static void perf_output_read_group(struct perf_output_handle *handle, | |
eed01528 SE |
5502 | struct perf_event *event, |
5503 | u64 enabled, u64 running) | |
3dab77fb | 5504 | { |
cdd6c482 IM |
5505 | struct perf_event *leader = event->group_leader, *sub; |
5506 | u64 read_format = event->attr.read_format; | |
3dab77fb PZ |
5507 | u64 values[5]; |
5508 | int n = 0; | |
5509 | ||
5510 | values[n++] = 1 + leader->nr_siblings; | |
5511 | ||
5512 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
eed01528 | 5513 | values[n++] = enabled; |
3dab77fb PZ |
5514 | |
5515 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
eed01528 | 5516 | values[n++] = running; |
3dab77fb | 5517 | |
cdd6c482 | 5518 | if (leader != event) |
3dab77fb PZ |
5519 | leader->pmu->read(leader); |
5520 | ||
b5e58793 | 5521 | values[n++] = perf_event_count(leader); |
3dab77fb | 5522 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 5523 | values[n++] = primary_event_id(leader); |
3dab77fb | 5524 | |
76369139 | 5525 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb | 5526 | |
65abc865 | 5527 | list_for_each_entry(sub, &leader->sibling_list, group_entry) { |
3dab77fb PZ |
5528 | n = 0; |
5529 | ||
6f5ab001 JO |
5530 | if ((sub != event) && |
5531 | (sub->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
5532 | sub->pmu->read(sub); |
5533 | ||
b5e58793 | 5534 | values[n++] = perf_event_count(sub); |
3dab77fb | 5535 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 5536 | values[n++] = primary_event_id(sub); |
3dab77fb | 5537 | |
76369139 | 5538 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
5539 | } |
5540 | } | |
5541 | ||
eed01528 SE |
5542 | #define PERF_FORMAT_TOTAL_TIMES (PERF_FORMAT_TOTAL_TIME_ENABLED|\ |
5543 | PERF_FORMAT_TOTAL_TIME_RUNNING) | |
5544 | ||
3dab77fb | 5545 | static void perf_output_read(struct perf_output_handle *handle, |
cdd6c482 | 5546 | struct perf_event *event) |
3dab77fb | 5547 | { |
e3f3541c | 5548 | u64 enabled = 0, running = 0, now; |
eed01528 SE |
5549 | u64 read_format = event->attr.read_format; |
5550 | ||
5551 | /* | |
5552 | * compute total_time_enabled, total_time_running | |
5553 | * based on snapshot values taken when the event | |
5554 | * was last scheduled in. | |
5555 | * | |
5556 | * we cannot simply called update_context_time() | |
5557 | * because of locking issue as we are called in | |
5558 | * NMI context | |
5559 | */ | |
c4794295 | 5560 | if (read_format & PERF_FORMAT_TOTAL_TIMES) |
e3f3541c | 5561 | calc_timer_values(event, &now, &enabled, &running); |
eed01528 | 5562 | |
cdd6c482 | 5563 | if (event->attr.read_format & PERF_FORMAT_GROUP) |
eed01528 | 5564 | perf_output_read_group(handle, event, enabled, running); |
3dab77fb | 5565 | else |
eed01528 | 5566 | perf_output_read_one(handle, event, enabled, running); |
3dab77fb PZ |
5567 | } |
5568 | ||
5622f295 MM |
5569 | void perf_output_sample(struct perf_output_handle *handle, |
5570 | struct perf_event_header *header, | |
5571 | struct perf_sample_data *data, | |
cdd6c482 | 5572 | struct perf_event *event) |
5622f295 MM |
5573 | { |
5574 | u64 sample_type = data->type; | |
5575 | ||
5576 | perf_output_put(handle, *header); | |
5577 | ||
ff3d527c AH |
5578 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
5579 | perf_output_put(handle, data->id); | |
5580 | ||
5622f295 MM |
5581 | if (sample_type & PERF_SAMPLE_IP) |
5582 | perf_output_put(handle, data->ip); | |
5583 | ||
5584 | if (sample_type & PERF_SAMPLE_TID) | |
5585 | perf_output_put(handle, data->tid_entry); | |
5586 | ||
5587 | if (sample_type & PERF_SAMPLE_TIME) | |
5588 | perf_output_put(handle, data->time); | |
5589 | ||
5590 | if (sample_type & PERF_SAMPLE_ADDR) | |
5591 | perf_output_put(handle, data->addr); | |
5592 | ||
5593 | if (sample_type & PERF_SAMPLE_ID) | |
5594 | perf_output_put(handle, data->id); | |
5595 | ||
5596 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
5597 | perf_output_put(handle, data->stream_id); | |
5598 | ||
5599 | if (sample_type & PERF_SAMPLE_CPU) | |
5600 | perf_output_put(handle, data->cpu_entry); | |
5601 | ||
5602 | if (sample_type & PERF_SAMPLE_PERIOD) | |
5603 | perf_output_put(handle, data->period); | |
5604 | ||
5605 | if (sample_type & PERF_SAMPLE_READ) | |
cdd6c482 | 5606 | perf_output_read(handle, event); |
5622f295 MM |
5607 | |
5608 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { | |
5609 | if (data->callchain) { | |
5610 | int size = 1; | |
5611 | ||
5612 | if (data->callchain) | |
5613 | size += data->callchain->nr; | |
5614 | ||
5615 | size *= sizeof(u64); | |
5616 | ||
76369139 | 5617 | __output_copy(handle, data->callchain, size); |
5622f295 MM |
5618 | } else { |
5619 | u64 nr = 0; | |
5620 | perf_output_put(handle, nr); | |
5621 | } | |
5622 | } | |
5623 | ||
5624 | if (sample_type & PERF_SAMPLE_RAW) { | |
7e3f977e DB |
5625 | struct perf_raw_record *raw = data->raw; |
5626 | ||
5627 | if (raw) { | |
5628 | struct perf_raw_frag *frag = &raw->frag; | |
5629 | ||
5630 | perf_output_put(handle, raw->size); | |
5631 | do { | |
5632 | if (frag->copy) { | |
5633 | __output_custom(handle, frag->copy, | |
5634 | frag->data, frag->size); | |
5635 | } else { | |
5636 | __output_copy(handle, frag->data, | |
5637 | frag->size); | |
5638 | } | |
5639 | if (perf_raw_frag_last(frag)) | |
5640 | break; | |
5641 | frag = frag->next; | |
5642 | } while (1); | |
5643 | if (frag->pad) | |
5644 | __output_skip(handle, NULL, frag->pad); | |
5622f295 MM |
5645 | } else { |
5646 | struct { | |
5647 | u32 size; | |
5648 | u32 data; | |
5649 | } raw = { | |
5650 | .size = sizeof(u32), | |
5651 | .data = 0, | |
5652 | }; | |
5653 | perf_output_put(handle, raw); | |
5654 | } | |
5655 | } | |
a7ac67ea | 5656 | |
bce38cd5 SE |
5657 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { |
5658 | if (data->br_stack) { | |
5659 | size_t size; | |
5660 | ||
5661 | size = data->br_stack->nr | |
5662 | * sizeof(struct perf_branch_entry); | |
5663 | ||
5664 | perf_output_put(handle, data->br_stack->nr); | |
5665 | perf_output_copy(handle, data->br_stack->entries, size); | |
5666 | } else { | |
5667 | /* | |
5668 | * we always store at least the value of nr | |
5669 | */ | |
5670 | u64 nr = 0; | |
5671 | perf_output_put(handle, nr); | |
5672 | } | |
5673 | } | |
4018994f JO |
5674 | |
5675 | if (sample_type & PERF_SAMPLE_REGS_USER) { | |
5676 | u64 abi = data->regs_user.abi; | |
5677 | ||
5678 | /* | |
5679 | * If there are no regs to dump, notice it through | |
5680 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
5681 | */ | |
5682 | perf_output_put(handle, abi); | |
5683 | ||
5684 | if (abi) { | |
5685 | u64 mask = event->attr.sample_regs_user; | |
5686 | perf_output_sample_regs(handle, | |
5687 | data->regs_user.regs, | |
5688 | mask); | |
5689 | } | |
5690 | } | |
c5ebcedb | 5691 | |
a5cdd40c | 5692 | if (sample_type & PERF_SAMPLE_STACK_USER) { |
c5ebcedb JO |
5693 | perf_output_sample_ustack(handle, |
5694 | data->stack_user_size, | |
5695 | data->regs_user.regs); | |
a5cdd40c | 5696 | } |
c3feedf2 AK |
5697 | |
5698 | if (sample_type & PERF_SAMPLE_WEIGHT) | |
5699 | perf_output_put(handle, data->weight); | |
d6be9ad6 SE |
5700 | |
5701 | if (sample_type & PERF_SAMPLE_DATA_SRC) | |
5702 | perf_output_put(handle, data->data_src.val); | |
a5cdd40c | 5703 | |
fdfbbd07 AK |
5704 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
5705 | perf_output_put(handle, data->txn); | |
5706 | ||
60e2364e SE |
5707 | if (sample_type & PERF_SAMPLE_REGS_INTR) { |
5708 | u64 abi = data->regs_intr.abi; | |
5709 | /* | |
5710 | * If there are no regs to dump, notice it through | |
5711 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
5712 | */ | |
5713 | perf_output_put(handle, abi); | |
5714 | ||
5715 | if (abi) { | |
5716 | u64 mask = event->attr.sample_regs_intr; | |
5717 | ||
5718 | perf_output_sample_regs(handle, | |
5719 | data->regs_intr.regs, | |
5720 | mask); | |
5721 | } | |
5722 | } | |
5723 | ||
a5cdd40c PZ |
5724 | if (!event->attr.watermark) { |
5725 | int wakeup_events = event->attr.wakeup_events; | |
5726 | ||
5727 | if (wakeup_events) { | |
5728 | struct ring_buffer *rb = handle->rb; | |
5729 | int events = local_inc_return(&rb->events); | |
5730 | ||
5731 | if (events >= wakeup_events) { | |
5732 | local_sub(wakeup_events, &rb->events); | |
5733 | local_inc(&rb->wakeup); | |
5734 | } | |
5735 | } | |
5736 | } | |
5622f295 MM |
5737 | } |
5738 | ||
5739 | void perf_prepare_sample(struct perf_event_header *header, | |
5740 | struct perf_sample_data *data, | |
cdd6c482 | 5741 | struct perf_event *event, |
5622f295 | 5742 | struct pt_regs *regs) |
7b732a75 | 5743 | { |
cdd6c482 | 5744 | u64 sample_type = event->attr.sample_type; |
7b732a75 | 5745 | |
cdd6c482 | 5746 | header->type = PERF_RECORD_SAMPLE; |
c320c7b7 | 5747 | header->size = sizeof(*header) + event->header_size; |
5622f295 MM |
5748 | |
5749 | header->misc = 0; | |
5750 | header->misc |= perf_misc_flags(regs); | |
6fab0192 | 5751 | |
c980d109 | 5752 | __perf_event_header__init_id(header, data, event); |
6844c09d | 5753 | |
c320c7b7 | 5754 | if (sample_type & PERF_SAMPLE_IP) |
5622f295 MM |
5755 | data->ip = perf_instruction_pointer(regs); |
5756 | ||
b23f3325 | 5757 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { |
5622f295 | 5758 | int size = 1; |
394ee076 | 5759 | |
e6dab5ff | 5760 | data->callchain = perf_callchain(event, regs); |
5622f295 MM |
5761 | |
5762 | if (data->callchain) | |
5763 | size += data->callchain->nr; | |
5764 | ||
5765 | header->size += size * sizeof(u64); | |
394ee076 PZ |
5766 | } |
5767 | ||
3a43ce68 | 5768 | if (sample_type & PERF_SAMPLE_RAW) { |
7e3f977e DB |
5769 | struct perf_raw_record *raw = data->raw; |
5770 | int size; | |
5771 | ||
5772 | if (raw) { | |
5773 | struct perf_raw_frag *frag = &raw->frag; | |
5774 | u32 sum = 0; | |
5775 | ||
5776 | do { | |
5777 | sum += frag->size; | |
5778 | if (perf_raw_frag_last(frag)) | |
5779 | break; | |
5780 | frag = frag->next; | |
5781 | } while (1); | |
5782 | ||
5783 | size = round_up(sum + sizeof(u32), sizeof(u64)); | |
5784 | raw->size = size - sizeof(u32); | |
5785 | frag->pad = raw->size - sum; | |
5786 | } else { | |
5787 | size = sizeof(u64); | |
5788 | } | |
a044560c | 5789 | |
7e3f977e | 5790 | header->size += size; |
7f453c24 | 5791 | } |
bce38cd5 SE |
5792 | |
5793 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { | |
5794 | int size = sizeof(u64); /* nr */ | |
5795 | if (data->br_stack) { | |
5796 | size += data->br_stack->nr | |
5797 | * sizeof(struct perf_branch_entry); | |
5798 | } | |
5799 | header->size += size; | |
5800 | } | |
4018994f | 5801 | |
2565711f | 5802 | if (sample_type & (PERF_SAMPLE_REGS_USER | PERF_SAMPLE_STACK_USER)) |
88a7c26a AL |
5803 | perf_sample_regs_user(&data->regs_user, regs, |
5804 | &data->regs_user_copy); | |
2565711f | 5805 | |
4018994f JO |
5806 | if (sample_type & PERF_SAMPLE_REGS_USER) { |
5807 | /* regs dump ABI info */ | |
5808 | int size = sizeof(u64); | |
5809 | ||
4018994f JO |
5810 | if (data->regs_user.regs) { |
5811 | u64 mask = event->attr.sample_regs_user; | |
5812 | size += hweight64(mask) * sizeof(u64); | |
5813 | } | |
5814 | ||
5815 | header->size += size; | |
5816 | } | |
c5ebcedb JO |
5817 | |
5818 | if (sample_type & PERF_SAMPLE_STACK_USER) { | |
5819 | /* | |
5820 | * Either we need PERF_SAMPLE_STACK_USER bit to be allways | |
5821 | * processed as the last one or have additional check added | |
5822 | * in case new sample type is added, because we could eat | |
5823 | * up the rest of the sample size. | |
5824 | */ | |
c5ebcedb JO |
5825 | u16 stack_size = event->attr.sample_stack_user; |
5826 | u16 size = sizeof(u64); | |
5827 | ||
c5ebcedb | 5828 | stack_size = perf_sample_ustack_size(stack_size, header->size, |
2565711f | 5829 | data->regs_user.regs); |
c5ebcedb JO |
5830 | |
5831 | /* | |
5832 | * If there is something to dump, add space for the dump | |
5833 | * itself and for the field that tells the dynamic size, | |
5834 | * which is how many have been actually dumped. | |
5835 | */ | |
5836 | if (stack_size) | |
5837 | size += sizeof(u64) + stack_size; | |
5838 | ||
5839 | data->stack_user_size = stack_size; | |
5840 | header->size += size; | |
5841 | } | |
60e2364e SE |
5842 | |
5843 | if (sample_type & PERF_SAMPLE_REGS_INTR) { | |
5844 | /* regs dump ABI info */ | |
5845 | int size = sizeof(u64); | |
5846 | ||
5847 | perf_sample_regs_intr(&data->regs_intr, regs); | |
5848 | ||
5849 | if (data->regs_intr.regs) { | |
5850 | u64 mask = event->attr.sample_regs_intr; | |
5851 | ||
5852 | size += hweight64(mask) * sizeof(u64); | |
5853 | } | |
5854 | ||
5855 | header->size += size; | |
5856 | } | |
5622f295 | 5857 | } |
7f453c24 | 5858 | |
9ecda41a WN |
5859 | static void __always_inline |
5860 | __perf_event_output(struct perf_event *event, | |
5861 | struct perf_sample_data *data, | |
5862 | struct pt_regs *regs, | |
5863 | int (*output_begin)(struct perf_output_handle *, | |
5864 | struct perf_event *, | |
5865 | unsigned int)) | |
5622f295 MM |
5866 | { |
5867 | struct perf_output_handle handle; | |
5868 | struct perf_event_header header; | |
689802b2 | 5869 | |
927c7a9e FW |
5870 | /* protect the callchain buffers */ |
5871 | rcu_read_lock(); | |
5872 | ||
cdd6c482 | 5873 | perf_prepare_sample(&header, data, event, regs); |
5c148194 | 5874 | |
9ecda41a | 5875 | if (output_begin(&handle, event, header.size)) |
927c7a9e | 5876 | goto exit; |
0322cd6e | 5877 | |
cdd6c482 | 5878 | perf_output_sample(&handle, &header, data, event); |
f413cdb8 | 5879 | |
8a057d84 | 5880 | perf_output_end(&handle); |
927c7a9e FW |
5881 | |
5882 | exit: | |
5883 | rcu_read_unlock(); | |
0322cd6e PZ |
5884 | } |
5885 | ||
9ecda41a WN |
5886 | void |
5887 | perf_event_output_forward(struct perf_event *event, | |
5888 | struct perf_sample_data *data, | |
5889 | struct pt_regs *regs) | |
5890 | { | |
5891 | __perf_event_output(event, data, regs, perf_output_begin_forward); | |
5892 | } | |
5893 | ||
5894 | void | |
5895 | perf_event_output_backward(struct perf_event *event, | |
5896 | struct perf_sample_data *data, | |
5897 | struct pt_regs *regs) | |
5898 | { | |
5899 | __perf_event_output(event, data, regs, perf_output_begin_backward); | |
5900 | } | |
5901 | ||
5902 | void | |
5903 | perf_event_output(struct perf_event *event, | |
5904 | struct perf_sample_data *data, | |
5905 | struct pt_regs *regs) | |
5906 | { | |
5907 | __perf_event_output(event, data, regs, perf_output_begin); | |
5908 | } | |
5909 | ||
38b200d6 | 5910 | /* |
cdd6c482 | 5911 | * read event_id |
38b200d6 PZ |
5912 | */ |
5913 | ||
5914 | struct perf_read_event { | |
5915 | struct perf_event_header header; | |
5916 | ||
5917 | u32 pid; | |
5918 | u32 tid; | |
38b200d6 PZ |
5919 | }; |
5920 | ||
5921 | static void | |
cdd6c482 | 5922 | perf_event_read_event(struct perf_event *event, |
38b200d6 PZ |
5923 | struct task_struct *task) |
5924 | { | |
5925 | struct perf_output_handle handle; | |
c980d109 | 5926 | struct perf_sample_data sample; |
dfc65094 | 5927 | struct perf_read_event read_event = { |
38b200d6 | 5928 | .header = { |
cdd6c482 | 5929 | .type = PERF_RECORD_READ, |
38b200d6 | 5930 | .misc = 0, |
c320c7b7 | 5931 | .size = sizeof(read_event) + event->read_size, |
38b200d6 | 5932 | }, |
cdd6c482 IM |
5933 | .pid = perf_event_pid(event, task), |
5934 | .tid = perf_event_tid(event, task), | |
38b200d6 | 5935 | }; |
3dab77fb | 5936 | int ret; |
38b200d6 | 5937 | |
c980d109 | 5938 | perf_event_header__init_id(&read_event.header, &sample, event); |
a7ac67ea | 5939 | ret = perf_output_begin(&handle, event, read_event.header.size); |
38b200d6 PZ |
5940 | if (ret) |
5941 | return; | |
5942 | ||
dfc65094 | 5943 | perf_output_put(&handle, read_event); |
cdd6c482 | 5944 | perf_output_read(&handle, event); |
c980d109 | 5945 | perf_event__output_id_sample(event, &handle, &sample); |
3dab77fb | 5946 | |
38b200d6 PZ |
5947 | perf_output_end(&handle); |
5948 | } | |
5949 | ||
aab5b71e | 5950 | typedef void (perf_iterate_f)(struct perf_event *event, void *data); |
52d857a8 JO |
5951 | |
5952 | static void | |
aab5b71e PZ |
5953 | perf_iterate_ctx(struct perf_event_context *ctx, |
5954 | perf_iterate_f output, | |
b73e4fef | 5955 | void *data, bool all) |
52d857a8 JO |
5956 | { |
5957 | struct perf_event *event; | |
5958 | ||
5959 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
b73e4fef AS |
5960 | if (!all) { |
5961 | if (event->state < PERF_EVENT_STATE_INACTIVE) | |
5962 | continue; | |
5963 | if (!event_filter_match(event)) | |
5964 | continue; | |
5965 | } | |
5966 | ||
67516844 | 5967 | output(event, data); |
52d857a8 JO |
5968 | } |
5969 | } | |
5970 | ||
aab5b71e | 5971 | static void perf_iterate_sb_cpu(perf_iterate_f output, void *data) |
f2fb6bef KL |
5972 | { |
5973 | struct pmu_event_list *pel = this_cpu_ptr(&pmu_sb_events); | |
5974 | struct perf_event *event; | |
5975 | ||
5976 | list_for_each_entry_rcu(event, &pel->list, sb_list) { | |
0b8f1e2e PZ |
5977 | /* |
5978 | * Skip events that are not fully formed yet; ensure that | |
5979 | * if we observe event->ctx, both event and ctx will be | |
5980 | * complete enough. See perf_install_in_context(). | |
5981 | */ | |
5982 | if (!smp_load_acquire(&event->ctx)) | |
5983 | continue; | |
5984 | ||
f2fb6bef KL |
5985 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
5986 | continue; | |
5987 | if (!event_filter_match(event)) | |
5988 | continue; | |
5989 | output(event, data); | |
5990 | } | |
5991 | } | |
5992 | ||
aab5b71e PZ |
5993 | /* |
5994 | * Iterate all events that need to receive side-band events. | |
5995 | * | |
5996 | * For new callers; ensure that account_pmu_sb_event() includes | |
5997 | * your event, otherwise it might not get delivered. | |
5998 | */ | |
52d857a8 | 5999 | static void |
aab5b71e | 6000 | perf_iterate_sb(perf_iterate_f output, void *data, |
52d857a8 JO |
6001 | struct perf_event_context *task_ctx) |
6002 | { | |
52d857a8 | 6003 | struct perf_event_context *ctx; |
52d857a8 JO |
6004 | int ctxn; |
6005 | ||
aab5b71e PZ |
6006 | rcu_read_lock(); |
6007 | preempt_disable(); | |
6008 | ||
4e93ad60 | 6009 | /* |
aab5b71e PZ |
6010 | * If we have task_ctx != NULL we only notify the task context itself. |
6011 | * The task_ctx is set only for EXIT events before releasing task | |
4e93ad60 JO |
6012 | * context. |
6013 | */ | |
6014 | if (task_ctx) { | |
aab5b71e PZ |
6015 | perf_iterate_ctx(task_ctx, output, data, false); |
6016 | goto done; | |
4e93ad60 JO |
6017 | } |
6018 | ||
aab5b71e | 6019 | perf_iterate_sb_cpu(output, data); |
f2fb6bef KL |
6020 | |
6021 | for_each_task_context_nr(ctxn) { | |
52d857a8 JO |
6022 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); |
6023 | if (ctx) | |
aab5b71e | 6024 | perf_iterate_ctx(ctx, output, data, false); |
52d857a8 | 6025 | } |
aab5b71e | 6026 | done: |
f2fb6bef | 6027 | preempt_enable(); |
52d857a8 | 6028 | rcu_read_unlock(); |
95ff4ca2 AS |
6029 | } |
6030 | ||
375637bc AS |
6031 | /* |
6032 | * Clear all file-based filters at exec, they'll have to be | |
6033 | * re-instated when/if these objects are mmapped again. | |
6034 | */ | |
6035 | static void perf_event_addr_filters_exec(struct perf_event *event, void *data) | |
6036 | { | |
6037 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
6038 | struct perf_addr_filter *filter; | |
6039 | unsigned int restart = 0, count = 0; | |
6040 | unsigned long flags; | |
6041 | ||
6042 | if (!has_addr_filter(event)) | |
6043 | return; | |
6044 | ||
6045 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
6046 | list_for_each_entry(filter, &ifh->list, entry) { | |
6047 | if (filter->inode) { | |
6048 | event->addr_filters_offs[count] = 0; | |
6049 | restart++; | |
6050 | } | |
6051 | ||
6052 | count++; | |
6053 | } | |
6054 | ||
6055 | if (restart) | |
6056 | event->addr_filters_gen++; | |
6057 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
6058 | ||
6059 | if (restart) | |
6060 | perf_event_restart(event); | |
6061 | } | |
6062 | ||
6063 | void perf_event_exec(void) | |
6064 | { | |
6065 | struct perf_event_context *ctx; | |
6066 | int ctxn; | |
6067 | ||
6068 | rcu_read_lock(); | |
6069 | for_each_task_context_nr(ctxn) { | |
6070 | ctx = current->perf_event_ctxp[ctxn]; | |
6071 | if (!ctx) | |
6072 | continue; | |
6073 | ||
6074 | perf_event_enable_on_exec(ctxn); | |
6075 | ||
aab5b71e | 6076 | perf_iterate_ctx(ctx, perf_event_addr_filters_exec, NULL, |
375637bc AS |
6077 | true); |
6078 | } | |
6079 | rcu_read_unlock(); | |
6080 | } | |
6081 | ||
95ff4ca2 AS |
6082 | struct remote_output { |
6083 | struct ring_buffer *rb; | |
6084 | int err; | |
6085 | }; | |
6086 | ||
6087 | static void __perf_event_output_stop(struct perf_event *event, void *data) | |
6088 | { | |
6089 | struct perf_event *parent = event->parent; | |
6090 | struct remote_output *ro = data; | |
6091 | struct ring_buffer *rb = ro->rb; | |
375637bc AS |
6092 | struct stop_event_data sd = { |
6093 | .event = event, | |
6094 | }; | |
95ff4ca2 AS |
6095 | |
6096 | if (!has_aux(event)) | |
6097 | return; | |
6098 | ||
6099 | if (!parent) | |
6100 | parent = event; | |
6101 | ||
6102 | /* | |
6103 | * In case of inheritance, it will be the parent that links to the | |
6104 | * ring-buffer, but it will be the child that's actually using it: | |
6105 | */ | |
6106 | if (rcu_dereference(parent->rb) == rb) | |
375637bc | 6107 | ro->err = __perf_event_stop(&sd); |
95ff4ca2 AS |
6108 | } |
6109 | ||
6110 | static int __perf_pmu_output_stop(void *info) | |
6111 | { | |
6112 | struct perf_event *event = info; | |
6113 | struct pmu *pmu = event->pmu; | |
6114 | struct perf_cpu_context *cpuctx = get_cpu_ptr(pmu->pmu_cpu_context); | |
6115 | struct remote_output ro = { | |
6116 | .rb = event->rb, | |
6117 | }; | |
6118 | ||
6119 | rcu_read_lock(); | |
aab5b71e | 6120 | perf_iterate_ctx(&cpuctx->ctx, __perf_event_output_stop, &ro, false); |
95ff4ca2 | 6121 | if (cpuctx->task_ctx) |
aab5b71e | 6122 | perf_iterate_ctx(cpuctx->task_ctx, __perf_event_output_stop, |
b73e4fef | 6123 | &ro, false); |
95ff4ca2 AS |
6124 | rcu_read_unlock(); |
6125 | ||
6126 | return ro.err; | |
6127 | } | |
6128 | ||
6129 | static void perf_pmu_output_stop(struct perf_event *event) | |
6130 | { | |
6131 | struct perf_event *iter; | |
6132 | int err, cpu; | |
6133 | ||
6134 | restart: | |
6135 | rcu_read_lock(); | |
6136 | list_for_each_entry_rcu(iter, &event->rb->event_list, rb_entry) { | |
6137 | /* | |
6138 | * For per-CPU events, we need to make sure that neither they | |
6139 | * nor their children are running; for cpu==-1 events it's | |
6140 | * sufficient to stop the event itself if it's active, since | |
6141 | * it can't have children. | |
6142 | */ | |
6143 | cpu = iter->cpu; | |
6144 | if (cpu == -1) | |
6145 | cpu = READ_ONCE(iter->oncpu); | |
6146 | ||
6147 | if (cpu == -1) | |
6148 | continue; | |
6149 | ||
6150 | err = cpu_function_call(cpu, __perf_pmu_output_stop, event); | |
6151 | if (err == -EAGAIN) { | |
6152 | rcu_read_unlock(); | |
6153 | goto restart; | |
6154 | } | |
6155 | } | |
6156 | rcu_read_unlock(); | |
52d857a8 JO |
6157 | } |
6158 | ||
60313ebe | 6159 | /* |
9f498cc5 PZ |
6160 | * task tracking -- fork/exit |
6161 | * | |
13d7a241 | 6162 | * enabled by: attr.comm | attr.mmap | attr.mmap2 | attr.mmap_data | attr.task |
60313ebe PZ |
6163 | */ |
6164 | ||
9f498cc5 | 6165 | struct perf_task_event { |
3a80b4a3 | 6166 | struct task_struct *task; |
cdd6c482 | 6167 | struct perf_event_context *task_ctx; |
60313ebe PZ |
6168 | |
6169 | struct { | |
6170 | struct perf_event_header header; | |
6171 | ||
6172 | u32 pid; | |
6173 | u32 ppid; | |
9f498cc5 PZ |
6174 | u32 tid; |
6175 | u32 ptid; | |
393b2ad8 | 6176 | u64 time; |
cdd6c482 | 6177 | } event_id; |
60313ebe PZ |
6178 | }; |
6179 | ||
67516844 JO |
6180 | static int perf_event_task_match(struct perf_event *event) |
6181 | { | |
13d7a241 SE |
6182 | return event->attr.comm || event->attr.mmap || |
6183 | event->attr.mmap2 || event->attr.mmap_data || | |
6184 | event->attr.task; | |
67516844 JO |
6185 | } |
6186 | ||
cdd6c482 | 6187 | static void perf_event_task_output(struct perf_event *event, |
52d857a8 | 6188 | void *data) |
60313ebe | 6189 | { |
52d857a8 | 6190 | struct perf_task_event *task_event = data; |
60313ebe | 6191 | struct perf_output_handle handle; |
c980d109 | 6192 | struct perf_sample_data sample; |
9f498cc5 | 6193 | struct task_struct *task = task_event->task; |
c980d109 | 6194 | int ret, size = task_event->event_id.header.size; |
8bb39f9a | 6195 | |
67516844 JO |
6196 | if (!perf_event_task_match(event)) |
6197 | return; | |
6198 | ||
c980d109 | 6199 | perf_event_header__init_id(&task_event->event_id.header, &sample, event); |
60313ebe | 6200 | |
c980d109 | 6201 | ret = perf_output_begin(&handle, event, |
a7ac67ea | 6202 | task_event->event_id.header.size); |
ef60777c | 6203 | if (ret) |
c980d109 | 6204 | goto out; |
60313ebe | 6205 | |
cdd6c482 IM |
6206 | task_event->event_id.pid = perf_event_pid(event, task); |
6207 | task_event->event_id.ppid = perf_event_pid(event, current); | |
60313ebe | 6208 | |
cdd6c482 IM |
6209 | task_event->event_id.tid = perf_event_tid(event, task); |
6210 | task_event->event_id.ptid = perf_event_tid(event, current); | |
9f498cc5 | 6211 | |
34f43927 PZ |
6212 | task_event->event_id.time = perf_event_clock(event); |
6213 | ||
cdd6c482 | 6214 | perf_output_put(&handle, task_event->event_id); |
393b2ad8 | 6215 | |
c980d109 ACM |
6216 | perf_event__output_id_sample(event, &handle, &sample); |
6217 | ||
60313ebe | 6218 | perf_output_end(&handle); |
c980d109 ACM |
6219 | out: |
6220 | task_event->event_id.header.size = size; | |
60313ebe PZ |
6221 | } |
6222 | ||
cdd6c482 IM |
6223 | static void perf_event_task(struct task_struct *task, |
6224 | struct perf_event_context *task_ctx, | |
3a80b4a3 | 6225 | int new) |
60313ebe | 6226 | { |
9f498cc5 | 6227 | struct perf_task_event task_event; |
60313ebe | 6228 | |
cdd6c482 IM |
6229 | if (!atomic_read(&nr_comm_events) && |
6230 | !atomic_read(&nr_mmap_events) && | |
6231 | !atomic_read(&nr_task_events)) | |
60313ebe PZ |
6232 | return; |
6233 | ||
9f498cc5 | 6234 | task_event = (struct perf_task_event){ |
3a80b4a3 PZ |
6235 | .task = task, |
6236 | .task_ctx = task_ctx, | |
cdd6c482 | 6237 | .event_id = { |
60313ebe | 6238 | .header = { |
cdd6c482 | 6239 | .type = new ? PERF_RECORD_FORK : PERF_RECORD_EXIT, |
573402db | 6240 | .misc = 0, |
cdd6c482 | 6241 | .size = sizeof(task_event.event_id), |
60313ebe | 6242 | }, |
573402db PZ |
6243 | /* .pid */ |
6244 | /* .ppid */ | |
9f498cc5 PZ |
6245 | /* .tid */ |
6246 | /* .ptid */ | |
34f43927 | 6247 | /* .time */ |
60313ebe PZ |
6248 | }, |
6249 | }; | |
6250 | ||
aab5b71e | 6251 | perf_iterate_sb(perf_event_task_output, |
52d857a8 JO |
6252 | &task_event, |
6253 | task_ctx); | |
9f498cc5 PZ |
6254 | } |
6255 | ||
cdd6c482 | 6256 | void perf_event_fork(struct task_struct *task) |
9f498cc5 | 6257 | { |
cdd6c482 | 6258 | perf_event_task(task, NULL, 1); |
60313ebe PZ |
6259 | } |
6260 | ||
8d1b2d93 PZ |
6261 | /* |
6262 | * comm tracking | |
6263 | */ | |
6264 | ||
6265 | struct perf_comm_event { | |
22a4f650 IM |
6266 | struct task_struct *task; |
6267 | char *comm; | |
8d1b2d93 PZ |
6268 | int comm_size; |
6269 | ||
6270 | struct { | |
6271 | struct perf_event_header header; | |
6272 | ||
6273 | u32 pid; | |
6274 | u32 tid; | |
cdd6c482 | 6275 | } event_id; |
8d1b2d93 PZ |
6276 | }; |
6277 | ||
67516844 JO |
6278 | static int perf_event_comm_match(struct perf_event *event) |
6279 | { | |
6280 | return event->attr.comm; | |
6281 | } | |
6282 | ||
cdd6c482 | 6283 | static void perf_event_comm_output(struct perf_event *event, |
52d857a8 | 6284 | void *data) |
8d1b2d93 | 6285 | { |
52d857a8 | 6286 | struct perf_comm_event *comm_event = data; |
8d1b2d93 | 6287 | struct perf_output_handle handle; |
c980d109 | 6288 | struct perf_sample_data sample; |
cdd6c482 | 6289 | int size = comm_event->event_id.header.size; |
c980d109 ACM |
6290 | int ret; |
6291 | ||
67516844 JO |
6292 | if (!perf_event_comm_match(event)) |
6293 | return; | |
6294 | ||
c980d109 ACM |
6295 | perf_event_header__init_id(&comm_event->event_id.header, &sample, event); |
6296 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 6297 | comm_event->event_id.header.size); |
8d1b2d93 PZ |
6298 | |
6299 | if (ret) | |
c980d109 | 6300 | goto out; |
8d1b2d93 | 6301 | |
cdd6c482 IM |
6302 | comm_event->event_id.pid = perf_event_pid(event, comm_event->task); |
6303 | comm_event->event_id.tid = perf_event_tid(event, comm_event->task); | |
709e50cf | 6304 | |
cdd6c482 | 6305 | perf_output_put(&handle, comm_event->event_id); |
76369139 | 6306 | __output_copy(&handle, comm_event->comm, |
8d1b2d93 | 6307 | comm_event->comm_size); |
c980d109 ACM |
6308 | |
6309 | perf_event__output_id_sample(event, &handle, &sample); | |
6310 | ||
8d1b2d93 | 6311 | perf_output_end(&handle); |
c980d109 ACM |
6312 | out: |
6313 | comm_event->event_id.header.size = size; | |
8d1b2d93 PZ |
6314 | } |
6315 | ||
cdd6c482 | 6316 | static void perf_event_comm_event(struct perf_comm_event *comm_event) |
8d1b2d93 | 6317 | { |
413ee3b4 | 6318 | char comm[TASK_COMM_LEN]; |
8d1b2d93 | 6319 | unsigned int size; |
8d1b2d93 | 6320 | |
413ee3b4 | 6321 | memset(comm, 0, sizeof(comm)); |
96b02d78 | 6322 | strlcpy(comm, comm_event->task->comm, sizeof(comm)); |
888fcee0 | 6323 | size = ALIGN(strlen(comm)+1, sizeof(u64)); |
8d1b2d93 PZ |
6324 | |
6325 | comm_event->comm = comm; | |
6326 | comm_event->comm_size = size; | |
6327 | ||
cdd6c482 | 6328 | comm_event->event_id.header.size = sizeof(comm_event->event_id) + size; |
8dc85d54 | 6329 | |
aab5b71e | 6330 | perf_iterate_sb(perf_event_comm_output, |
52d857a8 JO |
6331 | comm_event, |
6332 | NULL); | |
8d1b2d93 PZ |
6333 | } |
6334 | ||
82b89778 | 6335 | void perf_event_comm(struct task_struct *task, bool exec) |
8d1b2d93 | 6336 | { |
9ee318a7 PZ |
6337 | struct perf_comm_event comm_event; |
6338 | ||
cdd6c482 | 6339 | if (!atomic_read(&nr_comm_events)) |
9ee318a7 | 6340 | return; |
a63eaf34 | 6341 | |
9ee318a7 | 6342 | comm_event = (struct perf_comm_event){ |
8d1b2d93 | 6343 | .task = task, |
573402db PZ |
6344 | /* .comm */ |
6345 | /* .comm_size */ | |
cdd6c482 | 6346 | .event_id = { |
573402db | 6347 | .header = { |
cdd6c482 | 6348 | .type = PERF_RECORD_COMM, |
82b89778 | 6349 | .misc = exec ? PERF_RECORD_MISC_COMM_EXEC : 0, |
573402db PZ |
6350 | /* .size */ |
6351 | }, | |
6352 | /* .pid */ | |
6353 | /* .tid */ | |
8d1b2d93 PZ |
6354 | }, |
6355 | }; | |
6356 | ||
cdd6c482 | 6357 | perf_event_comm_event(&comm_event); |
8d1b2d93 PZ |
6358 | } |
6359 | ||
0a4a9391 PZ |
6360 | /* |
6361 | * mmap tracking | |
6362 | */ | |
6363 | ||
6364 | struct perf_mmap_event { | |
089dd79d PZ |
6365 | struct vm_area_struct *vma; |
6366 | ||
6367 | const char *file_name; | |
6368 | int file_size; | |
13d7a241 SE |
6369 | int maj, min; |
6370 | u64 ino; | |
6371 | u64 ino_generation; | |
f972eb63 | 6372 | u32 prot, flags; |
0a4a9391 PZ |
6373 | |
6374 | struct { | |
6375 | struct perf_event_header header; | |
6376 | ||
6377 | u32 pid; | |
6378 | u32 tid; | |
6379 | u64 start; | |
6380 | u64 len; | |
6381 | u64 pgoff; | |
cdd6c482 | 6382 | } event_id; |
0a4a9391 PZ |
6383 | }; |
6384 | ||
67516844 JO |
6385 | static int perf_event_mmap_match(struct perf_event *event, |
6386 | void *data) | |
6387 | { | |
6388 | struct perf_mmap_event *mmap_event = data; | |
6389 | struct vm_area_struct *vma = mmap_event->vma; | |
6390 | int executable = vma->vm_flags & VM_EXEC; | |
6391 | ||
6392 | return (!executable && event->attr.mmap_data) || | |
13d7a241 | 6393 | (executable && (event->attr.mmap || event->attr.mmap2)); |
67516844 JO |
6394 | } |
6395 | ||
cdd6c482 | 6396 | static void perf_event_mmap_output(struct perf_event *event, |
52d857a8 | 6397 | void *data) |
0a4a9391 | 6398 | { |
52d857a8 | 6399 | struct perf_mmap_event *mmap_event = data; |
0a4a9391 | 6400 | struct perf_output_handle handle; |
c980d109 | 6401 | struct perf_sample_data sample; |
cdd6c482 | 6402 | int size = mmap_event->event_id.header.size; |
c980d109 | 6403 | int ret; |
0a4a9391 | 6404 | |
67516844 JO |
6405 | if (!perf_event_mmap_match(event, data)) |
6406 | return; | |
6407 | ||
13d7a241 SE |
6408 | if (event->attr.mmap2) { |
6409 | mmap_event->event_id.header.type = PERF_RECORD_MMAP2; | |
6410 | mmap_event->event_id.header.size += sizeof(mmap_event->maj); | |
6411 | mmap_event->event_id.header.size += sizeof(mmap_event->min); | |
6412 | mmap_event->event_id.header.size += sizeof(mmap_event->ino); | |
d008d525 | 6413 | mmap_event->event_id.header.size += sizeof(mmap_event->ino_generation); |
f972eb63 PZ |
6414 | mmap_event->event_id.header.size += sizeof(mmap_event->prot); |
6415 | mmap_event->event_id.header.size += sizeof(mmap_event->flags); | |
13d7a241 SE |
6416 | } |
6417 | ||
c980d109 ACM |
6418 | perf_event_header__init_id(&mmap_event->event_id.header, &sample, event); |
6419 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 6420 | mmap_event->event_id.header.size); |
0a4a9391 | 6421 | if (ret) |
c980d109 | 6422 | goto out; |
0a4a9391 | 6423 | |
cdd6c482 IM |
6424 | mmap_event->event_id.pid = perf_event_pid(event, current); |
6425 | mmap_event->event_id.tid = perf_event_tid(event, current); | |
709e50cf | 6426 | |
cdd6c482 | 6427 | perf_output_put(&handle, mmap_event->event_id); |
13d7a241 SE |
6428 | |
6429 | if (event->attr.mmap2) { | |
6430 | perf_output_put(&handle, mmap_event->maj); | |
6431 | perf_output_put(&handle, mmap_event->min); | |
6432 | perf_output_put(&handle, mmap_event->ino); | |
6433 | perf_output_put(&handle, mmap_event->ino_generation); | |
f972eb63 PZ |
6434 | perf_output_put(&handle, mmap_event->prot); |
6435 | perf_output_put(&handle, mmap_event->flags); | |
13d7a241 SE |
6436 | } |
6437 | ||
76369139 | 6438 | __output_copy(&handle, mmap_event->file_name, |
0a4a9391 | 6439 | mmap_event->file_size); |
c980d109 ACM |
6440 | |
6441 | perf_event__output_id_sample(event, &handle, &sample); | |
6442 | ||
78d613eb | 6443 | perf_output_end(&handle); |
c980d109 ACM |
6444 | out: |
6445 | mmap_event->event_id.header.size = size; | |
0a4a9391 PZ |
6446 | } |
6447 | ||
cdd6c482 | 6448 | static void perf_event_mmap_event(struct perf_mmap_event *mmap_event) |
0a4a9391 | 6449 | { |
089dd79d PZ |
6450 | struct vm_area_struct *vma = mmap_event->vma; |
6451 | struct file *file = vma->vm_file; | |
13d7a241 SE |
6452 | int maj = 0, min = 0; |
6453 | u64 ino = 0, gen = 0; | |
f972eb63 | 6454 | u32 prot = 0, flags = 0; |
0a4a9391 PZ |
6455 | unsigned int size; |
6456 | char tmp[16]; | |
6457 | char *buf = NULL; | |
2c42cfbf | 6458 | char *name; |
413ee3b4 | 6459 | |
0a4a9391 | 6460 | if (file) { |
13d7a241 SE |
6461 | struct inode *inode; |
6462 | dev_t dev; | |
3ea2f2b9 | 6463 | |
2c42cfbf | 6464 | buf = kmalloc(PATH_MAX, GFP_KERNEL); |
0a4a9391 | 6465 | if (!buf) { |
c7e548b4 ON |
6466 | name = "//enomem"; |
6467 | goto cpy_name; | |
0a4a9391 | 6468 | } |
413ee3b4 | 6469 | /* |
3ea2f2b9 | 6470 | * d_path() works from the end of the rb backwards, so we |
413ee3b4 AB |
6471 | * need to add enough zero bytes after the string to handle |
6472 | * the 64bit alignment we do later. | |
6473 | */ | |
9bf39ab2 | 6474 | name = file_path(file, buf, PATH_MAX - sizeof(u64)); |
0a4a9391 | 6475 | if (IS_ERR(name)) { |
c7e548b4 ON |
6476 | name = "//toolong"; |
6477 | goto cpy_name; | |
0a4a9391 | 6478 | } |
13d7a241 SE |
6479 | inode = file_inode(vma->vm_file); |
6480 | dev = inode->i_sb->s_dev; | |
6481 | ino = inode->i_ino; | |
6482 | gen = inode->i_generation; | |
6483 | maj = MAJOR(dev); | |
6484 | min = MINOR(dev); | |
f972eb63 PZ |
6485 | |
6486 | if (vma->vm_flags & VM_READ) | |
6487 | prot |= PROT_READ; | |
6488 | if (vma->vm_flags & VM_WRITE) | |
6489 | prot |= PROT_WRITE; | |
6490 | if (vma->vm_flags & VM_EXEC) | |
6491 | prot |= PROT_EXEC; | |
6492 | ||
6493 | if (vma->vm_flags & VM_MAYSHARE) | |
6494 | flags = MAP_SHARED; | |
6495 | else | |
6496 | flags = MAP_PRIVATE; | |
6497 | ||
6498 | if (vma->vm_flags & VM_DENYWRITE) | |
6499 | flags |= MAP_DENYWRITE; | |
6500 | if (vma->vm_flags & VM_MAYEXEC) | |
6501 | flags |= MAP_EXECUTABLE; | |
6502 | if (vma->vm_flags & VM_LOCKED) | |
6503 | flags |= MAP_LOCKED; | |
6504 | if (vma->vm_flags & VM_HUGETLB) | |
6505 | flags |= MAP_HUGETLB; | |
6506 | ||
c7e548b4 | 6507 | goto got_name; |
0a4a9391 | 6508 | } else { |
fbe26abe JO |
6509 | if (vma->vm_ops && vma->vm_ops->name) { |
6510 | name = (char *) vma->vm_ops->name(vma); | |
6511 | if (name) | |
6512 | goto cpy_name; | |
6513 | } | |
6514 | ||
2c42cfbf | 6515 | name = (char *)arch_vma_name(vma); |
c7e548b4 ON |
6516 | if (name) |
6517 | goto cpy_name; | |
089dd79d | 6518 | |
32c5fb7e | 6519 | if (vma->vm_start <= vma->vm_mm->start_brk && |
3af9e859 | 6520 | vma->vm_end >= vma->vm_mm->brk) { |
c7e548b4 ON |
6521 | name = "[heap]"; |
6522 | goto cpy_name; | |
32c5fb7e ON |
6523 | } |
6524 | if (vma->vm_start <= vma->vm_mm->start_stack && | |
3af9e859 | 6525 | vma->vm_end >= vma->vm_mm->start_stack) { |
c7e548b4 ON |
6526 | name = "[stack]"; |
6527 | goto cpy_name; | |
089dd79d PZ |
6528 | } |
6529 | ||
c7e548b4 ON |
6530 | name = "//anon"; |
6531 | goto cpy_name; | |
0a4a9391 PZ |
6532 | } |
6533 | ||
c7e548b4 ON |
6534 | cpy_name: |
6535 | strlcpy(tmp, name, sizeof(tmp)); | |
6536 | name = tmp; | |
0a4a9391 | 6537 | got_name: |
2c42cfbf PZ |
6538 | /* |
6539 | * Since our buffer works in 8 byte units we need to align our string | |
6540 | * size to a multiple of 8. However, we must guarantee the tail end is | |
6541 | * zero'd out to avoid leaking random bits to userspace. | |
6542 | */ | |
6543 | size = strlen(name)+1; | |
6544 | while (!IS_ALIGNED(size, sizeof(u64))) | |
6545 | name[size++] = '\0'; | |
0a4a9391 PZ |
6546 | |
6547 | mmap_event->file_name = name; | |
6548 | mmap_event->file_size = size; | |
13d7a241 SE |
6549 | mmap_event->maj = maj; |
6550 | mmap_event->min = min; | |
6551 | mmap_event->ino = ino; | |
6552 | mmap_event->ino_generation = gen; | |
f972eb63 PZ |
6553 | mmap_event->prot = prot; |
6554 | mmap_event->flags = flags; | |
0a4a9391 | 6555 | |
2fe85427 SE |
6556 | if (!(vma->vm_flags & VM_EXEC)) |
6557 | mmap_event->event_id.header.misc |= PERF_RECORD_MISC_MMAP_DATA; | |
6558 | ||
cdd6c482 | 6559 | mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size; |
0a4a9391 | 6560 | |
aab5b71e | 6561 | perf_iterate_sb(perf_event_mmap_output, |
52d857a8 JO |
6562 | mmap_event, |
6563 | NULL); | |
665c2142 | 6564 | |
0a4a9391 PZ |
6565 | kfree(buf); |
6566 | } | |
6567 | ||
375637bc AS |
6568 | /* |
6569 | * Whether this @filter depends on a dynamic object which is not loaded | |
6570 | * yet or its load addresses are not known. | |
6571 | */ | |
6572 | static bool perf_addr_filter_needs_mmap(struct perf_addr_filter *filter) | |
6573 | { | |
6574 | return filter->filter && filter->inode; | |
6575 | } | |
6576 | ||
6577 | /* | |
6578 | * Check whether inode and address range match filter criteria. | |
6579 | */ | |
6580 | static bool perf_addr_filter_match(struct perf_addr_filter *filter, | |
6581 | struct file *file, unsigned long offset, | |
6582 | unsigned long size) | |
6583 | { | |
6584 | if (filter->inode != file->f_inode) | |
6585 | return false; | |
6586 | ||
6587 | if (filter->offset > offset + size) | |
6588 | return false; | |
6589 | ||
6590 | if (filter->offset + filter->size < offset) | |
6591 | return false; | |
6592 | ||
6593 | return true; | |
6594 | } | |
6595 | ||
6596 | static void __perf_addr_filters_adjust(struct perf_event *event, void *data) | |
6597 | { | |
6598 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
6599 | struct vm_area_struct *vma = data; | |
6600 | unsigned long off = vma->vm_pgoff << PAGE_SHIFT, flags; | |
6601 | struct file *file = vma->vm_file; | |
6602 | struct perf_addr_filter *filter; | |
6603 | unsigned int restart = 0, count = 0; | |
6604 | ||
6605 | if (!has_addr_filter(event)) | |
6606 | return; | |
6607 | ||
6608 | if (!file) | |
6609 | return; | |
6610 | ||
6611 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
6612 | list_for_each_entry(filter, &ifh->list, entry) { | |
6613 | if (perf_addr_filter_match(filter, file, off, | |
6614 | vma->vm_end - vma->vm_start)) { | |
6615 | event->addr_filters_offs[count] = vma->vm_start; | |
6616 | restart++; | |
6617 | } | |
6618 | ||
6619 | count++; | |
6620 | } | |
6621 | ||
6622 | if (restart) | |
6623 | event->addr_filters_gen++; | |
6624 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
6625 | ||
6626 | if (restart) | |
6627 | perf_event_restart(event); | |
6628 | } | |
6629 | ||
6630 | /* | |
6631 | * Adjust all task's events' filters to the new vma | |
6632 | */ | |
6633 | static void perf_addr_filters_adjust(struct vm_area_struct *vma) | |
6634 | { | |
6635 | struct perf_event_context *ctx; | |
6636 | int ctxn; | |
6637 | ||
6638 | rcu_read_lock(); | |
6639 | for_each_task_context_nr(ctxn) { | |
6640 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); | |
6641 | if (!ctx) | |
6642 | continue; | |
6643 | ||
aab5b71e | 6644 | perf_iterate_ctx(ctx, __perf_addr_filters_adjust, vma, true); |
375637bc AS |
6645 | } |
6646 | rcu_read_unlock(); | |
6647 | } | |
6648 | ||
3af9e859 | 6649 | void perf_event_mmap(struct vm_area_struct *vma) |
0a4a9391 | 6650 | { |
9ee318a7 PZ |
6651 | struct perf_mmap_event mmap_event; |
6652 | ||
cdd6c482 | 6653 | if (!atomic_read(&nr_mmap_events)) |
9ee318a7 PZ |
6654 | return; |
6655 | ||
6656 | mmap_event = (struct perf_mmap_event){ | |
089dd79d | 6657 | .vma = vma, |
573402db PZ |
6658 | /* .file_name */ |
6659 | /* .file_size */ | |
cdd6c482 | 6660 | .event_id = { |
573402db | 6661 | .header = { |
cdd6c482 | 6662 | .type = PERF_RECORD_MMAP, |
39447b38 | 6663 | .misc = PERF_RECORD_MISC_USER, |
573402db PZ |
6664 | /* .size */ |
6665 | }, | |
6666 | /* .pid */ | |
6667 | /* .tid */ | |
089dd79d PZ |
6668 | .start = vma->vm_start, |
6669 | .len = vma->vm_end - vma->vm_start, | |
3a0304e9 | 6670 | .pgoff = (u64)vma->vm_pgoff << PAGE_SHIFT, |
0a4a9391 | 6671 | }, |
13d7a241 SE |
6672 | /* .maj (attr_mmap2 only) */ |
6673 | /* .min (attr_mmap2 only) */ | |
6674 | /* .ino (attr_mmap2 only) */ | |
6675 | /* .ino_generation (attr_mmap2 only) */ | |
f972eb63 PZ |
6676 | /* .prot (attr_mmap2 only) */ |
6677 | /* .flags (attr_mmap2 only) */ | |
0a4a9391 PZ |
6678 | }; |
6679 | ||
375637bc | 6680 | perf_addr_filters_adjust(vma); |
cdd6c482 | 6681 | perf_event_mmap_event(&mmap_event); |
0a4a9391 PZ |
6682 | } |
6683 | ||
68db7e98 AS |
6684 | void perf_event_aux_event(struct perf_event *event, unsigned long head, |
6685 | unsigned long size, u64 flags) | |
6686 | { | |
6687 | struct perf_output_handle handle; | |
6688 | struct perf_sample_data sample; | |
6689 | struct perf_aux_event { | |
6690 | struct perf_event_header header; | |
6691 | u64 offset; | |
6692 | u64 size; | |
6693 | u64 flags; | |
6694 | } rec = { | |
6695 | .header = { | |
6696 | .type = PERF_RECORD_AUX, | |
6697 | .misc = 0, | |
6698 | .size = sizeof(rec), | |
6699 | }, | |
6700 | .offset = head, | |
6701 | .size = size, | |
6702 | .flags = flags, | |
6703 | }; | |
6704 | int ret; | |
6705 | ||
6706 | perf_event_header__init_id(&rec.header, &sample, event); | |
6707 | ret = perf_output_begin(&handle, event, rec.header.size); | |
6708 | ||
6709 | if (ret) | |
6710 | return; | |
6711 | ||
6712 | perf_output_put(&handle, rec); | |
6713 | perf_event__output_id_sample(event, &handle, &sample); | |
6714 | ||
6715 | perf_output_end(&handle); | |
6716 | } | |
6717 | ||
f38b0dbb KL |
6718 | /* |
6719 | * Lost/dropped samples logging | |
6720 | */ | |
6721 | void perf_log_lost_samples(struct perf_event *event, u64 lost) | |
6722 | { | |
6723 | struct perf_output_handle handle; | |
6724 | struct perf_sample_data sample; | |
6725 | int ret; | |
6726 | ||
6727 | struct { | |
6728 | struct perf_event_header header; | |
6729 | u64 lost; | |
6730 | } lost_samples_event = { | |
6731 | .header = { | |
6732 | .type = PERF_RECORD_LOST_SAMPLES, | |
6733 | .misc = 0, | |
6734 | .size = sizeof(lost_samples_event), | |
6735 | }, | |
6736 | .lost = lost, | |
6737 | }; | |
6738 | ||
6739 | perf_event_header__init_id(&lost_samples_event.header, &sample, event); | |
6740 | ||
6741 | ret = perf_output_begin(&handle, event, | |
6742 | lost_samples_event.header.size); | |
6743 | if (ret) | |
6744 | return; | |
6745 | ||
6746 | perf_output_put(&handle, lost_samples_event); | |
6747 | perf_event__output_id_sample(event, &handle, &sample); | |
6748 | perf_output_end(&handle); | |
6749 | } | |
6750 | ||
45ac1403 AH |
6751 | /* |
6752 | * context_switch tracking | |
6753 | */ | |
6754 | ||
6755 | struct perf_switch_event { | |
6756 | struct task_struct *task; | |
6757 | struct task_struct *next_prev; | |
6758 | ||
6759 | struct { | |
6760 | struct perf_event_header header; | |
6761 | u32 next_prev_pid; | |
6762 | u32 next_prev_tid; | |
6763 | } event_id; | |
6764 | }; | |
6765 | ||
6766 | static int perf_event_switch_match(struct perf_event *event) | |
6767 | { | |
6768 | return event->attr.context_switch; | |
6769 | } | |
6770 | ||
6771 | static void perf_event_switch_output(struct perf_event *event, void *data) | |
6772 | { | |
6773 | struct perf_switch_event *se = data; | |
6774 | struct perf_output_handle handle; | |
6775 | struct perf_sample_data sample; | |
6776 | int ret; | |
6777 | ||
6778 | if (!perf_event_switch_match(event)) | |
6779 | return; | |
6780 | ||
6781 | /* Only CPU-wide events are allowed to see next/prev pid/tid */ | |
6782 | if (event->ctx->task) { | |
6783 | se->event_id.header.type = PERF_RECORD_SWITCH; | |
6784 | se->event_id.header.size = sizeof(se->event_id.header); | |
6785 | } else { | |
6786 | se->event_id.header.type = PERF_RECORD_SWITCH_CPU_WIDE; | |
6787 | se->event_id.header.size = sizeof(se->event_id); | |
6788 | se->event_id.next_prev_pid = | |
6789 | perf_event_pid(event, se->next_prev); | |
6790 | se->event_id.next_prev_tid = | |
6791 | perf_event_tid(event, se->next_prev); | |
6792 | } | |
6793 | ||
6794 | perf_event_header__init_id(&se->event_id.header, &sample, event); | |
6795 | ||
6796 | ret = perf_output_begin(&handle, event, se->event_id.header.size); | |
6797 | if (ret) | |
6798 | return; | |
6799 | ||
6800 | if (event->ctx->task) | |
6801 | perf_output_put(&handle, se->event_id.header); | |
6802 | else | |
6803 | perf_output_put(&handle, se->event_id); | |
6804 | ||
6805 | perf_event__output_id_sample(event, &handle, &sample); | |
6806 | ||
6807 | perf_output_end(&handle); | |
6808 | } | |
6809 | ||
6810 | static void perf_event_switch(struct task_struct *task, | |
6811 | struct task_struct *next_prev, bool sched_in) | |
6812 | { | |
6813 | struct perf_switch_event switch_event; | |
6814 | ||
6815 | /* N.B. caller checks nr_switch_events != 0 */ | |
6816 | ||
6817 | switch_event = (struct perf_switch_event){ | |
6818 | .task = task, | |
6819 | .next_prev = next_prev, | |
6820 | .event_id = { | |
6821 | .header = { | |
6822 | /* .type */ | |
6823 | .misc = sched_in ? 0 : PERF_RECORD_MISC_SWITCH_OUT, | |
6824 | /* .size */ | |
6825 | }, | |
6826 | /* .next_prev_pid */ | |
6827 | /* .next_prev_tid */ | |
6828 | }, | |
6829 | }; | |
6830 | ||
aab5b71e | 6831 | perf_iterate_sb(perf_event_switch_output, |
45ac1403 AH |
6832 | &switch_event, |
6833 | NULL); | |
6834 | } | |
6835 | ||
a78ac325 PZ |
6836 | /* |
6837 | * IRQ throttle logging | |
6838 | */ | |
6839 | ||
cdd6c482 | 6840 | static void perf_log_throttle(struct perf_event *event, int enable) |
a78ac325 PZ |
6841 | { |
6842 | struct perf_output_handle handle; | |
c980d109 | 6843 | struct perf_sample_data sample; |
a78ac325 PZ |
6844 | int ret; |
6845 | ||
6846 | struct { | |
6847 | struct perf_event_header header; | |
6848 | u64 time; | |
cca3f454 | 6849 | u64 id; |
7f453c24 | 6850 | u64 stream_id; |
a78ac325 PZ |
6851 | } throttle_event = { |
6852 | .header = { | |
cdd6c482 | 6853 | .type = PERF_RECORD_THROTTLE, |
a78ac325 PZ |
6854 | .misc = 0, |
6855 | .size = sizeof(throttle_event), | |
6856 | }, | |
34f43927 | 6857 | .time = perf_event_clock(event), |
cdd6c482 IM |
6858 | .id = primary_event_id(event), |
6859 | .stream_id = event->id, | |
a78ac325 PZ |
6860 | }; |
6861 | ||
966ee4d6 | 6862 | if (enable) |
cdd6c482 | 6863 | throttle_event.header.type = PERF_RECORD_UNTHROTTLE; |
966ee4d6 | 6864 | |
c980d109 ACM |
6865 | perf_event_header__init_id(&throttle_event.header, &sample, event); |
6866 | ||
6867 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 6868 | throttle_event.header.size); |
a78ac325 PZ |
6869 | if (ret) |
6870 | return; | |
6871 | ||
6872 | perf_output_put(&handle, throttle_event); | |
c980d109 | 6873 | perf_event__output_id_sample(event, &handle, &sample); |
a78ac325 PZ |
6874 | perf_output_end(&handle); |
6875 | } | |
6876 | ||
ec0d7729 AS |
6877 | static void perf_log_itrace_start(struct perf_event *event) |
6878 | { | |
6879 | struct perf_output_handle handle; | |
6880 | struct perf_sample_data sample; | |
6881 | struct perf_aux_event { | |
6882 | struct perf_event_header header; | |
6883 | u32 pid; | |
6884 | u32 tid; | |
6885 | } rec; | |
6886 | int ret; | |
6887 | ||
6888 | if (event->parent) | |
6889 | event = event->parent; | |
6890 | ||
6891 | if (!(event->pmu->capabilities & PERF_PMU_CAP_ITRACE) || | |
6892 | event->hw.itrace_started) | |
6893 | return; | |
6894 | ||
ec0d7729 AS |
6895 | rec.header.type = PERF_RECORD_ITRACE_START; |
6896 | rec.header.misc = 0; | |
6897 | rec.header.size = sizeof(rec); | |
6898 | rec.pid = perf_event_pid(event, current); | |
6899 | rec.tid = perf_event_tid(event, current); | |
6900 | ||
6901 | perf_event_header__init_id(&rec.header, &sample, event); | |
6902 | ret = perf_output_begin(&handle, event, rec.header.size); | |
6903 | ||
6904 | if (ret) | |
6905 | return; | |
6906 | ||
6907 | perf_output_put(&handle, rec); | |
6908 | perf_event__output_id_sample(event, &handle, &sample); | |
6909 | ||
6910 | perf_output_end(&handle); | |
6911 | } | |
6912 | ||
f6c7d5fe | 6913 | /* |
cdd6c482 | 6914 | * Generic event overflow handling, sampling. |
f6c7d5fe PZ |
6915 | */ |
6916 | ||
a8b0ca17 | 6917 | static int __perf_event_overflow(struct perf_event *event, |
5622f295 MM |
6918 | int throttle, struct perf_sample_data *data, |
6919 | struct pt_regs *regs) | |
f6c7d5fe | 6920 | { |
cdd6c482 IM |
6921 | int events = atomic_read(&event->event_limit); |
6922 | struct hw_perf_event *hwc = &event->hw; | |
e050e3f0 | 6923 | u64 seq; |
79f14641 PZ |
6924 | int ret = 0; |
6925 | ||
96398826 PZ |
6926 | /* |
6927 | * Non-sampling counters might still use the PMI to fold short | |
6928 | * hardware counters, ignore those. | |
6929 | */ | |
6930 | if (unlikely(!is_sampling_event(event))) | |
6931 | return 0; | |
6932 | ||
e050e3f0 SE |
6933 | seq = __this_cpu_read(perf_throttled_seq); |
6934 | if (seq != hwc->interrupts_seq) { | |
6935 | hwc->interrupts_seq = seq; | |
6936 | hwc->interrupts = 1; | |
6937 | } else { | |
6938 | hwc->interrupts++; | |
6939 | if (unlikely(throttle | |
6940 | && hwc->interrupts >= max_samples_per_tick)) { | |
6941 | __this_cpu_inc(perf_throttled_count); | |
555e0c1e | 6942 | tick_dep_set_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
163ec435 PZ |
6943 | hwc->interrupts = MAX_INTERRUPTS; |
6944 | perf_log_throttle(event, 0); | |
a78ac325 PZ |
6945 | ret = 1; |
6946 | } | |
e050e3f0 | 6947 | } |
60db5e09 | 6948 | |
cdd6c482 | 6949 | if (event->attr.freq) { |
def0a9b2 | 6950 | u64 now = perf_clock(); |
abd50713 | 6951 | s64 delta = now - hwc->freq_time_stamp; |
bd2b5b12 | 6952 | |
abd50713 | 6953 | hwc->freq_time_stamp = now; |
bd2b5b12 | 6954 | |
abd50713 | 6955 | if (delta > 0 && delta < 2*TICK_NSEC) |
f39d47ff | 6956 | perf_adjust_period(event, delta, hwc->last_period, true); |
bd2b5b12 PZ |
6957 | } |
6958 | ||
2023b359 PZ |
6959 | /* |
6960 | * XXX event_limit might not quite work as expected on inherited | |
cdd6c482 | 6961 | * events |
2023b359 PZ |
6962 | */ |
6963 | ||
cdd6c482 IM |
6964 | event->pending_kill = POLL_IN; |
6965 | if (events && atomic_dec_and_test(&event->event_limit)) { | |
79f14641 | 6966 | ret = 1; |
cdd6c482 | 6967 | event->pending_kill = POLL_HUP; |
a8b0ca17 PZ |
6968 | event->pending_disable = 1; |
6969 | irq_work_queue(&event->pending); | |
79f14641 PZ |
6970 | } |
6971 | ||
1879445d | 6972 | event->overflow_handler(event, data, regs); |
453f19ee | 6973 | |
fed66e2c | 6974 | if (*perf_event_fasync(event) && event->pending_kill) { |
a8b0ca17 PZ |
6975 | event->pending_wakeup = 1; |
6976 | irq_work_queue(&event->pending); | |
f506b3dc PZ |
6977 | } |
6978 | ||
79f14641 | 6979 | return ret; |
f6c7d5fe PZ |
6980 | } |
6981 | ||
a8b0ca17 | 6982 | int perf_event_overflow(struct perf_event *event, |
5622f295 MM |
6983 | struct perf_sample_data *data, |
6984 | struct pt_regs *regs) | |
850bc73f | 6985 | { |
a8b0ca17 | 6986 | return __perf_event_overflow(event, 1, data, regs); |
850bc73f PZ |
6987 | } |
6988 | ||
15dbf27c | 6989 | /* |
cdd6c482 | 6990 | * Generic software event infrastructure |
15dbf27c PZ |
6991 | */ |
6992 | ||
b28ab83c PZ |
6993 | struct swevent_htable { |
6994 | struct swevent_hlist *swevent_hlist; | |
6995 | struct mutex hlist_mutex; | |
6996 | int hlist_refcount; | |
6997 | ||
6998 | /* Recursion avoidance in each contexts */ | |
6999 | int recursion[PERF_NR_CONTEXTS]; | |
7000 | }; | |
7001 | ||
7002 | static DEFINE_PER_CPU(struct swevent_htable, swevent_htable); | |
7003 | ||
7b4b6658 | 7004 | /* |
cdd6c482 IM |
7005 | * We directly increment event->count and keep a second value in |
7006 | * event->hw.period_left to count intervals. This period event | |
7b4b6658 PZ |
7007 | * is kept in the range [-sample_period, 0] so that we can use the |
7008 | * sign as trigger. | |
7009 | */ | |
7010 | ||
ab573844 | 7011 | u64 perf_swevent_set_period(struct perf_event *event) |
15dbf27c | 7012 | { |
cdd6c482 | 7013 | struct hw_perf_event *hwc = &event->hw; |
7b4b6658 PZ |
7014 | u64 period = hwc->last_period; |
7015 | u64 nr, offset; | |
7016 | s64 old, val; | |
7017 | ||
7018 | hwc->last_period = hwc->sample_period; | |
15dbf27c PZ |
7019 | |
7020 | again: | |
e7850595 | 7021 | old = val = local64_read(&hwc->period_left); |
7b4b6658 PZ |
7022 | if (val < 0) |
7023 | return 0; | |
15dbf27c | 7024 | |
7b4b6658 PZ |
7025 | nr = div64_u64(period + val, period); |
7026 | offset = nr * period; | |
7027 | val -= offset; | |
e7850595 | 7028 | if (local64_cmpxchg(&hwc->period_left, old, val) != old) |
7b4b6658 | 7029 | goto again; |
15dbf27c | 7030 | |
7b4b6658 | 7031 | return nr; |
15dbf27c PZ |
7032 | } |
7033 | ||
0cff784a | 7034 | static void perf_swevent_overflow(struct perf_event *event, u64 overflow, |
a8b0ca17 | 7035 | struct perf_sample_data *data, |
5622f295 | 7036 | struct pt_regs *regs) |
15dbf27c | 7037 | { |
cdd6c482 | 7038 | struct hw_perf_event *hwc = &event->hw; |
850bc73f | 7039 | int throttle = 0; |
15dbf27c | 7040 | |
0cff784a PZ |
7041 | if (!overflow) |
7042 | overflow = perf_swevent_set_period(event); | |
15dbf27c | 7043 | |
7b4b6658 PZ |
7044 | if (hwc->interrupts == MAX_INTERRUPTS) |
7045 | return; | |
15dbf27c | 7046 | |
7b4b6658 | 7047 | for (; overflow; overflow--) { |
a8b0ca17 | 7048 | if (__perf_event_overflow(event, throttle, |
5622f295 | 7049 | data, regs)) { |
7b4b6658 PZ |
7050 | /* |
7051 | * We inhibit the overflow from happening when | |
7052 | * hwc->interrupts == MAX_INTERRUPTS. | |
7053 | */ | |
7054 | break; | |
7055 | } | |
cf450a73 | 7056 | throttle = 1; |
7b4b6658 | 7057 | } |
15dbf27c PZ |
7058 | } |
7059 | ||
a4eaf7f1 | 7060 | static void perf_swevent_event(struct perf_event *event, u64 nr, |
a8b0ca17 | 7061 | struct perf_sample_data *data, |
5622f295 | 7062 | struct pt_regs *regs) |
7b4b6658 | 7063 | { |
cdd6c482 | 7064 | struct hw_perf_event *hwc = &event->hw; |
d6d020e9 | 7065 | |
e7850595 | 7066 | local64_add(nr, &event->count); |
d6d020e9 | 7067 | |
0cff784a PZ |
7068 | if (!regs) |
7069 | return; | |
7070 | ||
6c7e550f | 7071 | if (!is_sampling_event(event)) |
7b4b6658 | 7072 | return; |
d6d020e9 | 7073 | |
5d81e5cf AV |
7074 | if ((event->attr.sample_type & PERF_SAMPLE_PERIOD) && !event->attr.freq) { |
7075 | data->period = nr; | |
7076 | return perf_swevent_overflow(event, 1, data, regs); | |
7077 | } else | |
7078 | data->period = event->hw.last_period; | |
7079 | ||
0cff784a | 7080 | if (nr == 1 && hwc->sample_period == 1 && !event->attr.freq) |
a8b0ca17 | 7081 | return perf_swevent_overflow(event, 1, data, regs); |
0cff784a | 7082 | |
e7850595 | 7083 | if (local64_add_negative(nr, &hwc->period_left)) |
7b4b6658 | 7084 | return; |
df1a132b | 7085 | |
a8b0ca17 | 7086 | perf_swevent_overflow(event, 0, data, regs); |
d6d020e9 PZ |
7087 | } |
7088 | ||
f5ffe02e FW |
7089 | static int perf_exclude_event(struct perf_event *event, |
7090 | struct pt_regs *regs) | |
7091 | { | |
a4eaf7f1 | 7092 | if (event->hw.state & PERF_HES_STOPPED) |
91b2f482 | 7093 | return 1; |
a4eaf7f1 | 7094 | |
f5ffe02e FW |
7095 | if (regs) { |
7096 | if (event->attr.exclude_user && user_mode(regs)) | |
7097 | return 1; | |
7098 | ||
7099 | if (event->attr.exclude_kernel && !user_mode(regs)) | |
7100 | return 1; | |
7101 | } | |
7102 | ||
7103 | return 0; | |
7104 | } | |
7105 | ||
cdd6c482 | 7106 | static int perf_swevent_match(struct perf_event *event, |
1c432d89 | 7107 | enum perf_type_id type, |
6fb2915d LZ |
7108 | u32 event_id, |
7109 | struct perf_sample_data *data, | |
7110 | struct pt_regs *regs) | |
15dbf27c | 7111 | { |
cdd6c482 | 7112 | if (event->attr.type != type) |
a21ca2ca | 7113 | return 0; |
f5ffe02e | 7114 | |
cdd6c482 | 7115 | if (event->attr.config != event_id) |
15dbf27c PZ |
7116 | return 0; |
7117 | ||
f5ffe02e FW |
7118 | if (perf_exclude_event(event, regs)) |
7119 | return 0; | |
15dbf27c PZ |
7120 | |
7121 | return 1; | |
7122 | } | |
7123 | ||
76e1d904 FW |
7124 | static inline u64 swevent_hash(u64 type, u32 event_id) |
7125 | { | |
7126 | u64 val = event_id | (type << 32); | |
7127 | ||
7128 | return hash_64(val, SWEVENT_HLIST_BITS); | |
7129 | } | |
7130 | ||
49f135ed FW |
7131 | static inline struct hlist_head * |
7132 | __find_swevent_head(struct swevent_hlist *hlist, u64 type, u32 event_id) | |
76e1d904 | 7133 | { |
49f135ed FW |
7134 | u64 hash = swevent_hash(type, event_id); |
7135 | ||
7136 | return &hlist->heads[hash]; | |
7137 | } | |
76e1d904 | 7138 | |
49f135ed FW |
7139 | /* For the read side: events when they trigger */ |
7140 | static inline struct hlist_head * | |
b28ab83c | 7141 | find_swevent_head_rcu(struct swevent_htable *swhash, u64 type, u32 event_id) |
49f135ed FW |
7142 | { |
7143 | struct swevent_hlist *hlist; | |
76e1d904 | 7144 | |
b28ab83c | 7145 | hlist = rcu_dereference(swhash->swevent_hlist); |
76e1d904 FW |
7146 | if (!hlist) |
7147 | return NULL; | |
7148 | ||
49f135ed FW |
7149 | return __find_swevent_head(hlist, type, event_id); |
7150 | } | |
7151 | ||
7152 | /* For the event head insertion and removal in the hlist */ | |
7153 | static inline struct hlist_head * | |
b28ab83c | 7154 | find_swevent_head(struct swevent_htable *swhash, struct perf_event *event) |
49f135ed FW |
7155 | { |
7156 | struct swevent_hlist *hlist; | |
7157 | u32 event_id = event->attr.config; | |
7158 | u64 type = event->attr.type; | |
7159 | ||
7160 | /* | |
7161 | * Event scheduling is always serialized against hlist allocation | |
7162 | * and release. Which makes the protected version suitable here. | |
7163 | * The context lock guarantees that. | |
7164 | */ | |
b28ab83c | 7165 | hlist = rcu_dereference_protected(swhash->swevent_hlist, |
49f135ed FW |
7166 | lockdep_is_held(&event->ctx->lock)); |
7167 | if (!hlist) | |
7168 | return NULL; | |
7169 | ||
7170 | return __find_swevent_head(hlist, type, event_id); | |
76e1d904 FW |
7171 | } |
7172 | ||
7173 | static void do_perf_sw_event(enum perf_type_id type, u32 event_id, | |
a8b0ca17 | 7174 | u64 nr, |
76e1d904 FW |
7175 | struct perf_sample_data *data, |
7176 | struct pt_regs *regs) | |
15dbf27c | 7177 | { |
4a32fea9 | 7178 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 7179 | struct perf_event *event; |
76e1d904 | 7180 | struct hlist_head *head; |
15dbf27c | 7181 | |
76e1d904 | 7182 | rcu_read_lock(); |
b28ab83c | 7183 | head = find_swevent_head_rcu(swhash, type, event_id); |
76e1d904 FW |
7184 | if (!head) |
7185 | goto end; | |
7186 | ||
b67bfe0d | 7187 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
6fb2915d | 7188 | if (perf_swevent_match(event, type, event_id, data, regs)) |
a8b0ca17 | 7189 | perf_swevent_event(event, nr, data, regs); |
15dbf27c | 7190 | } |
76e1d904 FW |
7191 | end: |
7192 | rcu_read_unlock(); | |
15dbf27c PZ |
7193 | } |
7194 | ||
86038c5e PZI |
7195 | DEFINE_PER_CPU(struct pt_regs, __perf_regs[4]); |
7196 | ||
4ed7c92d | 7197 | int perf_swevent_get_recursion_context(void) |
96f6d444 | 7198 | { |
4a32fea9 | 7199 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
96f6d444 | 7200 | |
b28ab83c | 7201 | return get_recursion_context(swhash->recursion); |
96f6d444 | 7202 | } |
645e8cc0 | 7203 | EXPORT_SYMBOL_GPL(perf_swevent_get_recursion_context); |
96f6d444 | 7204 | |
98b5c2c6 | 7205 | void perf_swevent_put_recursion_context(int rctx) |
15dbf27c | 7206 | { |
4a32fea9 | 7207 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
927c7a9e | 7208 | |
b28ab83c | 7209 | put_recursion_context(swhash->recursion, rctx); |
ce71b9df | 7210 | } |
15dbf27c | 7211 | |
86038c5e | 7212 | void ___perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) |
b8e83514 | 7213 | { |
a4234bfc | 7214 | struct perf_sample_data data; |
4ed7c92d | 7215 | |
86038c5e | 7216 | if (WARN_ON_ONCE(!regs)) |
4ed7c92d | 7217 | return; |
a4234bfc | 7218 | |
fd0d000b | 7219 | perf_sample_data_init(&data, addr, 0); |
a8b0ca17 | 7220 | do_perf_sw_event(PERF_TYPE_SOFTWARE, event_id, nr, &data, regs); |
86038c5e PZI |
7221 | } |
7222 | ||
7223 | void __perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) | |
7224 | { | |
7225 | int rctx; | |
7226 | ||
7227 | preempt_disable_notrace(); | |
7228 | rctx = perf_swevent_get_recursion_context(); | |
7229 | if (unlikely(rctx < 0)) | |
7230 | goto fail; | |
7231 | ||
7232 | ___perf_sw_event(event_id, nr, regs, addr); | |
4ed7c92d PZ |
7233 | |
7234 | perf_swevent_put_recursion_context(rctx); | |
86038c5e | 7235 | fail: |
1c024eca | 7236 | preempt_enable_notrace(); |
b8e83514 PZ |
7237 | } |
7238 | ||
cdd6c482 | 7239 | static void perf_swevent_read(struct perf_event *event) |
15dbf27c | 7240 | { |
15dbf27c PZ |
7241 | } |
7242 | ||
a4eaf7f1 | 7243 | static int perf_swevent_add(struct perf_event *event, int flags) |
15dbf27c | 7244 | { |
4a32fea9 | 7245 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 7246 | struct hw_perf_event *hwc = &event->hw; |
76e1d904 FW |
7247 | struct hlist_head *head; |
7248 | ||
6c7e550f | 7249 | if (is_sampling_event(event)) { |
7b4b6658 | 7250 | hwc->last_period = hwc->sample_period; |
cdd6c482 | 7251 | perf_swevent_set_period(event); |
7b4b6658 | 7252 | } |
76e1d904 | 7253 | |
a4eaf7f1 PZ |
7254 | hwc->state = !(flags & PERF_EF_START); |
7255 | ||
b28ab83c | 7256 | head = find_swevent_head(swhash, event); |
12ca6ad2 | 7257 | if (WARN_ON_ONCE(!head)) |
76e1d904 FW |
7258 | return -EINVAL; |
7259 | ||
7260 | hlist_add_head_rcu(&event->hlist_entry, head); | |
6a694a60 | 7261 | perf_event_update_userpage(event); |
76e1d904 | 7262 | |
15dbf27c PZ |
7263 | return 0; |
7264 | } | |
7265 | ||
a4eaf7f1 | 7266 | static void perf_swevent_del(struct perf_event *event, int flags) |
15dbf27c | 7267 | { |
76e1d904 | 7268 | hlist_del_rcu(&event->hlist_entry); |
15dbf27c PZ |
7269 | } |
7270 | ||
a4eaf7f1 | 7271 | static void perf_swevent_start(struct perf_event *event, int flags) |
5c92d124 | 7272 | { |
a4eaf7f1 | 7273 | event->hw.state = 0; |
d6d020e9 | 7274 | } |
aa9c4c0f | 7275 | |
a4eaf7f1 | 7276 | static void perf_swevent_stop(struct perf_event *event, int flags) |
d6d020e9 | 7277 | { |
a4eaf7f1 | 7278 | event->hw.state = PERF_HES_STOPPED; |
bae43c99 IM |
7279 | } |
7280 | ||
49f135ed FW |
7281 | /* Deref the hlist from the update side */ |
7282 | static inline struct swevent_hlist * | |
b28ab83c | 7283 | swevent_hlist_deref(struct swevent_htable *swhash) |
49f135ed | 7284 | { |
b28ab83c PZ |
7285 | return rcu_dereference_protected(swhash->swevent_hlist, |
7286 | lockdep_is_held(&swhash->hlist_mutex)); | |
49f135ed FW |
7287 | } |
7288 | ||
b28ab83c | 7289 | static void swevent_hlist_release(struct swevent_htable *swhash) |
76e1d904 | 7290 | { |
b28ab83c | 7291 | struct swevent_hlist *hlist = swevent_hlist_deref(swhash); |
76e1d904 | 7292 | |
49f135ed | 7293 | if (!hlist) |
76e1d904 FW |
7294 | return; |
7295 | ||
70691d4a | 7296 | RCU_INIT_POINTER(swhash->swevent_hlist, NULL); |
fa4bbc4c | 7297 | kfree_rcu(hlist, rcu_head); |
76e1d904 FW |
7298 | } |
7299 | ||
3b364d7b | 7300 | static void swevent_hlist_put_cpu(int cpu) |
76e1d904 | 7301 | { |
b28ab83c | 7302 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 | 7303 | |
b28ab83c | 7304 | mutex_lock(&swhash->hlist_mutex); |
76e1d904 | 7305 | |
b28ab83c PZ |
7306 | if (!--swhash->hlist_refcount) |
7307 | swevent_hlist_release(swhash); | |
76e1d904 | 7308 | |
b28ab83c | 7309 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
7310 | } |
7311 | ||
3b364d7b | 7312 | static void swevent_hlist_put(void) |
76e1d904 FW |
7313 | { |
7314 | int cpu; | |
7315 | ||
76e1d904 | 7316 | for_each_possible_cpu(cpu) |
3b364d7b | 7317 | swevent_hlist_put_cpu(cpu); |
76e1d904 FW |
7318 | } |
7319 | ||
3b364d7b | 7320 | static int swevent_hlist_get_cpu(int cpu) |
76e1d904 | 7321 | { |
b28ab83c | 7322 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 FW |
7323 | int err = 0; |
7324 | ||
b28ab83c | 7325 | mutex_lock(&swhash->hlist_mutex); |
b28ab83c | 7326 | if (!swevent_hlist_deref(swhash) && cpu_online(cpu)) { |
76e1d904 FW |
7327 | struct swevent_hlist *hlist; |
7328 | ||
7329 | hlist = kzalloc(sizeof(*hlist), GFP_KERNEL); | |
7330 | if (!hlist) { | |
7331 | err = -ENOMEM; | |
7332 | goto exit; | |
7333 | } | |
b28ab83c | 7334 | rcu_assign_pointer(swhash->swevent_hlist, hlist); |
76e1d904 | 7335 | } |
b28ab83c | 7336 | swhash->hlist_refcount++; |
9ed6060d | 7337 | exit: |
b28ab83c | 7338 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
7339 | |
7340 | return err; | |
7341 | } | |
7342 | ||
3b364d7b | 7343 | static int swevent_hlist_get(void) |
76e1d904 | 7344 | { |
3b364d7b | 7345 | int err, cpu, failed_cpu; |
76e1d904 | 7346 | |
76e1d904 FW |
7347 | get_online_cpus(); |
7348 | for_each_possible_cpu(cpu) { | |
3b364d7b | 7349 | err = swevent_hlist_get_cpu(cpu); |
76e1d904 FW |
7350 | if (err) { |
7351 | failed_cpu = cpu; | |
7352 | goto fail; | |
7353 | } | |
7354 | } | |
7355 | put_online_cpus(); | |
7356 | ||
7357 | return 0; | |
9ed6060d | 7358 | fail: |
76e1d904 FW |
7359 | for_each_possible_cpu(cpu) { |
7360 | if (cpu == failed_cpu) | |
7361 | break; | |
3b364d7b | 7362 | swevent_hlist_put_cpu(cpu); |
76e1d904 FW |
7363 | } |
7364 | ||
7365 | put_online_cpus(); | |
7366 | return err; | |
7367 | } | |
7368 | ||
c5905afb | 7369 | struct static_key perf_swevent_enabled[PERF_COUNT_SW_MAX]; |
95476b64 | 7370 | |
b0a873eb PZ |
7371 | static void sw_perf_event_destroy(struct perf_event *event) |
7372 | { | |
7373 | u64 event_id = event->attr.config; | |
95476b64 | 7374 | |
b0a873eb PZ |
7375 | WARN_ON(event->parent); |
7376 | ||
c5905afb | 7377 | static_key_slow_dec(&perf_swevent_enabled[event_id]); |
3b364d7b | 7378 | swevent_hlist_put(); |
b0a873eb PZ |
7379 | } |
7380 | ||
7381 | static int perf_swevent_init(struct perf_event *event) | |
7382 | { | |
8176cced | 7383 | u64 event_id = event->attr.config; |
b0a873eb PZ |
7384 | |
7385 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
7386 | return -ENOENT; | |
7387 | ||
2481c5fa SE |
7388 | /* |
7389 | * no branch sampling for software events | |
7390 | */ | |
7391 | if (has_branch_stack(event)) | |
7392 | return -EOPNOTSUPP; | |
7393 | ||
b0a873eb PZ |
7394 | switch (event_id) { |
7395 | case PERF_COUNT_SW_CPU_CLOCK: | |
7396 | case PERF_COUNT_SW_TASK_CLOCK: | |
7397 | return -ENOENT; | |
7398 | ||
7399 | default: | |
7400 | break; | |
7401 | } | |
7402 | ||
ce677831 | 7403 | if (event_id >= PERF_COUNT_SW_MAX) |
b0a873eb PZ |
7404 | return -ENOENT; |
7405 | ||
7406 | if (!event->parent) { | |
7407 | int err; | |
7408 | ||
3b364d7b | 7409 | err = swevent_hlist_get(); |
b0a873eb PZ |
7410 | if (err) |
7411 | return err; | |
7412 | ||
c5905afb | 7413 | static_key_slow_inc(&perf_swevent_enabled[event_id]); |
b0a873eb PZ |
7414 | event->destroy = sw_perf_event_destroy; |
7415 | } | |
7416 | ||
7417 | return 0; | |
7418 | } | |
7419 | ||
7420 | static struct pmu perf_swevent = { | |
89a1e187 | 7421 | .task_ctx_nr = perf_sw_context, |
95476b64 | 7422 | |
34f43927 PZ |
7423 | .capabilities = PERF_PMU_CAP_NO_NMI, |
7424 | ||
b0a873eb | 7425 | .event_init = perf_swevent_init, |
a4eaf7f1 PZ |
7426 | .add = perf_swevent_add, |
7427 | .del = perf_swevent_del, | |
7428 | .start = perf_swevent_start, | |
7429 | .stop = perf_swevent_stop, | |
1c024eca | 7430 | .read = perf_swevent_read, |
1c024eca PZ |
7431 | }; |
7432 | ||
b0a873eb PZ |
7433 | #ifdef CONFIG_EVENT_TRACING |
7434 | ||
1c024eca PZ |
7435 | static int perf_tp_filter_match(struct perf_event *event, |
7436 | struct perf_sample_data *data) | |
7437 | { | |
7e3f977e | 7438 | void *record = data->raw->frag.data; |
1c024eca | 7439 | |
b71b437e PZ |
7440 | /* only top level events have filters set */ |
7441 | if (event->parent) | |
7442 | event = event->parent; | |
7443 | ||
1c024eca PZ |
7444 | if (likely(!event->filter) || filter_match_preds(event->filter, record)) |
7445 | return 1; | |
7446 | return 0; | |
7447 | } | |
7448 | ||
7449 | static int perf_tp_event_match(struct perf_event *event, | |
7450 | struct perf_sample_data *data, | |
7451 | struct pt_regs *regs) | |
7452 | { | |
a0f7d0f7 FW |
7453 | if (event->hw.state & PERF_HES_STOPPED) |
7454 | return 0; | |
580d607c PZ |
7455 | /* |
7456 | * All tracepoints are from kernel-space. | |
7457 | */ | |
7458 | if (event->attr.exclude_kernel) | |
1c024eca PZ |
7459 | return 0; |
7460 | ||
7461 | if (!perf_tp_filter_match(event, data)) | |
7462 | return 0; | |
7463 | ||
7464 | return 1; | |
7465 | } | |
7466 | ||
85b67bcb AS |
7467 | void perf_trace_run_bpf_submit(void *raw_data, int size, int rctx, |
7468 | struct trace_event_call *call, u64 count, | |
7469 | struct pt_regs *regs, struct hlist_head *head, | |
7470 | struct task_struct *task) | |
7471 | { | |
7472 | struct bpf_prog *prog = call->prog; | |
7473 | ||
7474 | if (prog) { | |
7475 | *(struct pt_regs **)raw_data = regs; | |
7476 | if (!trace_call_bpf(prog, raw_data) || hlist_empty(head)) { | |
7477 | perf_swevent_put_recursion_context(rctx); | |
7478 | return; | |
7479 | } | |
7480 | } | |
7481 | perf_tp_event(call->event.type, count, raw_data, size, regs, head, | |
7482 | rctx, task); | |
7483 | } | |
7484 | EXPORT_SYMBOL_GPL(perf_trace_run_bpf_submit); | |
7485 | ||
1e1dcd93 | 7486 | void perf_tp_event(u16 event_type, u64 count, void *record, int entry_size, |
e6dab5ff AV |
7487 | struct pt_regs *regs, struct hlist_head *head, int rctx, |
7488 | struct task_struct *task) | |
95476b64 FW |
7489 | { |
7490 | struct perf_sample_data data; | |
1c024eca | 7491 | struct perf_event *event; |
1c024eca | 7492 | |
95476b64 | 7493 | struct perf_raw_record raw = { |
7e3f977e DB |
7494 | .frag = { |
7495 | .size = entry_size, | |
7496 | .data = record, | |
7497 | }, | |
95476b64 FW |
7498 | }; |
7499 | ||
1e1dcd93 | 7500 | perf_sample_data_init(&data, 0, 0); |
95476b64 FW |
7501 | data.raw = &raw; |
7502 | ||
1e1dcd93 AS |
7503 | perf_trace_buf_update(record, event_type); |
7504 | ||
b67bfe0d | 7505 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
1c024eca | 7506 | if (perf_tp_event_match(event, &data, regs)) |
a8b0ca17 | 7507 | perf_swevent_event(event, count, &data, regs); |
4f41c013 | 7508 | } |
ecc55f84 | 7509 | |
e6dab5ff AV |
7510 | /* |
7511 | * If we got specified a target task, also iterate its context and | |
7512 | * deliver this event there too. | |
7513 | */ | |
7514 | if (task && task != current) { | |
7515 | struct perf_event_context *ctx; | |
7516 | struct trace_entry *entry = record; | |
7517 | ||
7518 | rcu_read_lock(); | |
7519 | ctx = rcu_dereference(task->perf_event_ctxp[perf_sw_context]); | |
7520 | if (!ctx) | |
7521 | goto unlock; | |
7522 | ||
7523 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
7524 | if (event->attr.type != PERF_TYPE_TRACEPOINT) | |
7525 | continue; | |
7526 | if (event->attr.config != entry->type) | |
7527 | continue; | |
7528 | if (perf_tp_event_match(event, &data, regs)) | |
7529 | perf_swevent_event(event, count, &data, regs); | |
7530 | } | |
7531 | unlock: | |
7532 | rcu_read_unlock(); | |
7533 | } | |
7534 | ||
ecc55f84 | 7535 | perf_swevent_put_recursion_context(rctx); |
95476b64 FW |
7536 | } |
7537 | EXPORT_SYMBOL_GPL(perf_tp_event); | |
7538 | ||
cdd6c482 | 7539 | static void tp_perf_event_destroy(struct perf_event *event) |
e077df4f | 7540 | { |
1c024eca | 7541 | perf_trace_destroy(event); |
e077df4f PZ |
7542 | } |
7543 | ||
b0a873eb | 7544 | static int perf_tp_event_init(struct perf_event *event) |
e077df4f | 7545 | { |
76e1d904 FW |
7546 | int err; |
7547 | ||
b0a873eb PZ |
7548 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
7549 | return -ENOENT; | |
7550 | ||
2481c5fa SE |
7551 | /* |
7552 | * no branch sampling for tracepoint events | |
7553 | */ | |
7554 | if (has_branch_stack(event)) | |
7555 | return -EOPNOTSUPP; | |
7556 | ||
1c024eca PZ |
7557 | err = perf_trace_init(event); |
7558 | if (err) | |
b0a873eb | 7559 | return err; |
e077df4f | 7560 | |
cdd6c482 | 7561 | event->destroy = tp_perf_event_destroy; |
e077df4f | 7562 | |
b0a873eb PZ |
7563 | return 0; |
7564 | } | |
7565 | ||
7566 | static struct pmu perf_tracepoint = { | |
89a1e187 PZ |
7567 | .task_ctx_nr = perf_sw_context, |
7568 | ||
b0a873eb | 7569 | .event_init = perf_tp_event_init, |
a4eaf7f1 PZ |
7570 | .add = perf_trace_add, |
7571 | .del = perf_trace_del, | |
7572 | .start = perf_swevent_start, | |
7573 | .stop = perf_swevent_stop, | |
b0a873eb | 7574 | .read = perf_swevent_read, |
b0a873eb PZ |
7575 | }; |
7576 | ||
7577 | static inline void perf_tp_register(void) | |
7578 | { | |
2e80a82a | 7579 | perf_pmu_register(&perf_tracepoint, "tracepoint", PERF_TYPE_TRACEPOINT); |
e077df4f | 7580 | } |
6fb2915d | 7581 | |
6fb2915d LZ |
7582 | static void perf_event_free_filter(struct perf_event *event) |
7583 | { | |
7584 | ftrace_profile_free_filter(event); | |
7585 | } | |
7586 | ||
2541517c AS |
7587 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
7588 | { | |
98b5c2c6 | 7589 | bool is_kprobe, is_tracepoint; |
2541517c AS |
7590 | struct bpf_prog *prog; |
7591 | ||
7592 | if (event->attr.type != PERF_TYPE_TRACEPOINT) | |
7593 | return -EINVAL; | |
7594 | ||
7595 | if (event->tp_event->prog) | |
7596 | return -EEXIST; | |
7597 | ||
98b5c2c6 AS |
7598 | is_kprobe = event->tp_event->flags & TRACE_EVENT_FL_UKPROBE; |
7599 | is_tracepoint = event->tp_event->flags & TRACE_EVENT_FL_TRACEPOINT; | |
7600 | if (!is_kprobe && !is_tracepoint) | |
7601 | /* bpf programs can only be attached to u/kprobe or tracepoint */ | |
2541517c AS |
7602 | return -EINVAL; |
7603 | ||
7604 | prog = bpf_prog_get(prog_fd); | |
7605 | if (IS_ERR(prog)) | |
7606 | return PTR_ERR(prog); | |
7607 | ||
98b5c2c6 AS |
7608 | if ((is_kprobe && prog->type != BPF_PROG_TYPE_KPROBE) || |
7609 | (is_tracepoint && prog->type != BPF_PROG_TYPE_TRACEPOINT)) { | |
2541517c AS |
7610 | /* valid fd, but invalid bpf program type */ |
7611 | bpf_prog_put(prog); | |
7612 | return -EINVAL; | |
7613 | } | |
7614 | ||
32bbe007 AS |
7615 | if (is_tracepoint) { |
7616 | int off = trace_event_get_offsets(event->tp_event); | |
7617 | ||
7618 | if (prog->aux->max_ctx_offset > off) { | |
7619 | bpf_prog_put(prog); | |
7620 | return -EACCES; | |
7621 | } | |
7622 | } | |
2541517c AS |
7623 | event->tp_event->prog = prog; |
7624 | ||
7625 | return 0; | |
7626 | } | |
7627 | ||
7628 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
7629 | { | |
7630 | struct bpf_prog *prog; | |
7631 | ||
7632 | if (!event->tp_event) | |
7633 | return; | |
7634 | ||
7635 | prog = event->tp_event->prog; | |
7636 | if (prog) { | |
7637 | event->tp_event->prog = NULL; | |
1aacde3d | 7638 | bpf_prog_put(prog); |
2541517c AS |
7639 | } |
7640 | } | |
7641 | ||
e077df4f | 7642 | #else |
6fb2915d | 7643 | |
b0a873eb | 7644 | static inline void perf_tp_register(void) |
e077df4f | 7645 | { |
e077df4f | 7646 | } |
6fb2915d | 7647 | |
6fb2915d LZ |
7648 | static void perf_event_free_filter(struct perf_event *event) |
7649 | { | |
7650 | } | |
7651 | ||
2541517c AS |
7652 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
7653 | { | |
7654 | return -ENOENT; | |
7655 | } | |
7656 | ||
7657 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
7658 | { | |
7659 | } | |
07b139c8 | 7660 | #endif /* CONFIG_EVENT_TRACING */ |
e077df4f | 7661 | |
24f1e32c | 7662 | #ifdef CONFIG_HAVE_HW_BREAKPOINT |
f5ffe02e | 7663 | void perf_bp_event(struct perf_event *bp, void *data) |
24f1e32c | 7664 | { |
f5ffe02e FW |
7665 | struct perf_sample_data sample; |
7666 | struct pt_regs *regs = data; | |
7667 | ||
fd0d000b | 7668 | perf_sample_data_init(&sample, bp->attr.bp_addr, 0); |
f5ffe02e | 7669 | |
a4eaf7f1 | 7670 | if (!bp->hw.state && !perf_exclude_event(bp, regs)) |
a8b0ca17 | 7671 | perf_swevent_event(bp, 1, &sample, regs); |
24f1e32c FW |
7672 | } |
7673 | #endif | |
7674 | ||
375637bc AS |
7675 | /* |
7676 | * Allocate a new address filter | |
7677 | */ | |
7678 | static struct perf_addr_filter * | |
7679 | perf_addr_filter_new(struct perf_event *event, struct list_head *filters) | |
7680 | { | |
7681 | int node = cpu_to_node(event->cpu == -1 ? 0 : event->cpu); | |
7682 | struct perf_addr_filter *filter; | |
7683 | ||
7684 | filter = kzalloc_node(sizeof(*filter), GFP_KERNEL, node); | |
7685 | if (!filter) | |
7686 | return NULL; | |
7687 | ||
7688 | INIT_LIST_HEAD(&filter->entry); | |
7689 | list_add_tail(&filter->entry, filters); | |
7690 | ||
7691 | return filter; | |
7692 | } | |
7693 | ||
7694 | static void free_filters_list(struct list_head *filters) | |
7695 | { | |
7696 | struct perf_addr_filter *filter, *iter; | |
7697 | ||
7698 | list_for_each_entry_safe(filter, iter, filters, entry) { | |
7699 | if (filter->inode) | |
7700 | iput(filter->inode); | |
7701 | list_del(&filter->entry); | |
7702 | kfree(filter); | |
7703 | } | |
7704 | } | |
7705 | ||
7706 | /* | |
7707 | * Free existing address filters and optionally install new ones | |
7708 | */ | |
7709 | static void perf_addr_filters_splice(struct perf_event *event, | |
7710 | struct list_head *head) | |
7711 | { | |
7712 | unsigned long flags; | |
7713 | LIST_HEAD(list); | |
7714 | ||
7715 | if (!has_addr_filter(event)) | |
7716 | return; | |
7717 | ||
7718 | /* don't bother with children, they don't have their own filters */ | |
7719 | if (event->parent) | |
7720 | return; | |
7721 | ||
7722 | raw_spin_lock_irqsave(&event->addr_filters.lock, flags); | |
7723 | ||
7724 | list_splice_init(&event->addr_filters.list, &list); | |
7725 | if (head) | |
7726 | list_splice(head, &event->addr_filters.list); | |
7727 | ||
7728 | raw_spin_unlock_irqrestore(&event->addr_filters.lock, flags); | |
7729 | ||
7730 | free_filters_list(&list); | |
7731 | } | |
7732 | ||
7733 | /* | |
7734 | * Scan through mm's vmas and see if one of them matches the | |
7735 | * @filter; if so, adjust filter's address range. | |
7736 | * Called with mm::mmap_sem down for reading. | |
7737 | */ | |
7738 | static unsigned long perf_addr_filter_apply(struct perf_addr_filter *filter, | |
7739 | struct mm_struct *mm) | |
7740 | { | |
7741 | struct vm_area_struct *vma; | |
7742 | ||
7743 | for (vma = mm->mmap; vma; vma = vma->vm_next) { | |
7744 | struct file *file = vma->vm_file; | |
7745 | unsigned long off = vma->vm_pgoff << PAGE_SHIFT; | |
7746 | unsigned long vma_size = vma->vm_end - vma->vm_start; | |
7747 | ||
7748 | if (!file) | |
7749 | continue; | |
7750 | ||
7751 | if (!perf_addr_filter_match(filter, file, off, vma_size)) | |
7752 | continue; | |
7753 | ||
7754 | return vma->vm_start; | |
7755 | } | |
7756 | ||
7757 | return 0; | |
7758 | } | |
7759 | ||
7760 | /* | |
7761 | * Update event's address range filters based on the | |
7762 | * task's existing mappings, if any. | |
7763 | */ | |
7764 | static void perf_event_addr_filters_apply(struct perf_event *event) | |
7765 | { | |
7766 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
7767 | struct task_struct *task = READ_ONCE(event->ctx->task); | |
7768 | struct perf_addr_filter *filter; | |
7769 | struct mm_struct *mm = NULL; | |
7770 | unsigned int count = 0; | |
7771 | unsigned long flags; | |
7772 | ||
7773 | /* | |
7774 | * We may observe TASK_TOMBSTONE, which means that the event tear-down | |
7775 | * will stop on the parent's child_mutex that our caller is also holding | |
7776 | */ | |
7777 | if (task == TASK_TOMBSTONE) | |
7778 | return; | |
7779 | ||
7780 | mm = get_task_mm(event->ctx->task); | |
7781 | if (!mm) | |
7782 | goto restart; | |
7783 | ||
7784 | down_read(&mm->mmap_sem); | |
7785 | ||
7786 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
7787 | list_for_each_entry(filter, &ifh->list, entry) { | |
7788 | event->addr_filters_offs[count] = 0; | |
7789 | ||
7790 | if (perf_addr_filter_needs_mmap(filter)) | |
7791 | event->addr_filters_offs[count] = | |
7792 | perf_addr_filter_apply(filter, mm); | |
7793 | ||
7794 | count++; | |
7795 | } | |
7796 | ||
7797 | event->addr_filters_gen++; | |
7798 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
7799 | ||
7800 | up_read(&mm->mmap_sem); | |
7801 | ||
7802 | mmput(mm); | |
7803 | ||
7804 | restart: | |
7805 | perf_event_restart(event); | |
7806 | } | |
7807 | ||
7808 | /* | |
7809 | * Address range filtering: limiting the data to certain | |
7810 | * instruction address ranges. Filters are ioctl()ed to us from | |
7811 | * userspace as ascii strings. | |
7812 | * | |
7813 | * Filter string format: | |
7814 | * | |
7815 | * ACTION RANGE_SPEC | |
7816 | * where ACTION is one of the | |
7817 | * * "filter": limit the trace to this region | |
7818 | * * "start": start tracing from this address | |
7819 | * * "stop": stop tracing at this address/region; | |
7820 | * RANGE_SPEC is | |
7821 | * * for kernel addresses: <start address>[/<size>] | |
7822 | * * for object files: <start address>[/<size>]@</path/to/object/file> | |
7823 | * | |
7824 | * if <size> is not specified, the range is treated as a single address. | |
7825 | */ | |
7826 | enum { | |
7827 | IF_ACT_FILTER, | |
7828 | IF_ACT_START, | |
7829 | IF_ACT_STOP, | |
7830 | IF_SRC_FILE, | |
7831 | IF_SRC_KERNEL, | |
7832 | IF_SRC_FILEADDR, | |
7833 | IF_SRC_KERNELADDR, | |
7834 | }; | |
7835 | ||
7836 | enum { | |
7837 | IF_STATE_ACTION = 0, | |
7838 | IF_STATE_SOURCE, | |
7839 | IF_STATE_END, | |
7840 | }; | |
7841 | ||
7842 | static const match_table_t if_tokens = { | |
7843 | { IF_ACT_FILTER, "filter" }, | |
7844 | { IF_ACT_START, "start" }, | |
7845 | { IF_ACT_STOP, "stop" }, | |
7846 | { IF_SRC_FILE, "%u/%u@%s" }, | |
7847 | { IF_SRC_KERNEL, "%u/%u" }, | |
7848 | { IF_SRC_FILEADDR, "%u@%s" }, | |
7849 | { IF_SRC_KERNELADDR, "%u" }, | |
7850 | }; | |
7851 | ||
7852 | /* | |
7853 | * Address filter string parser | |
7854 | */ | |
7855 | static int | |
7856 | perf_event_parse_addr_filter(struct perf_event *event, char *fstr, | |
7857 | struct list_head *filters) | |
7858 | { | |
7859 | struct perf_addr_filter *filter = NULL; | |
7860 | char *start, *orig, *filename = NULL; | |
7861 | struct path path; | |
7862 | substring_t args[MAX_OPT_ARGS]; | |
7863 | int state = IF_STATE_ACTION, token; | |
7864 | unsigned int kernel = 0; | |
7865 | int ret = -EINVAL; | |
7866 | ||
7867 | orig = fstr = kstrdup(fstr, GFP_KERNEL); | |
7868 | if (!fstr) | |
7869 | return -ENOMEM; | |
7870 | ||
7871 | while ((start = strsep(&fstr, " ,\n")) != NULL) { | |
7872 | ret = -EINVAL; | |
7873 | ||
7874 | if (!*start) | |
7875 | continue; | |
7876 | ||
7877 | /* filter definition begins */ | |
7878 | if (state == IF_STATE_ACTION) { | |
7879 | filter = perf_addr_filter_new(event, filters); | |
7880 | if (!filter) | |
7881 | goto fail; | |
7882 | } | |
7883 | ||
7884 | token = match_token(start, if_tokens, args); | |
7885 | switch (token) { | |
7886 | case IF_ACT_FILTER: | |
7887 | case IF_ACT_START: | |
7888 | filter->filter = 1; | |
7889 | ||
7890 | case IF_ACT_STOP: | |
7891 | if (state != IF_STATE_ACTION) | |
7892 | goto fail; | |
7893 | ||
7894 | state = IF_STATE_SOURCE; | |
7895 | break; | |
7896 | ||
7897 | case IF_SRC_KERNELADDR: | |
7898 | case IF_SRC_KERNEL: | |
7899 | kernel = 1; | |
7900 | ||
7901 | case IF_SRC_FILEADDR: | |
7902 | case IF_SRC_FILE: | |
7903 | if (state != IF_STATE_SOURCE) | |
7904 | goto fail; | |
7905 | ||
7906 | if (token == IF_SRC_FILE || token == IF_SRC_KERNEL) | |
7907 | filter->range = 1; | |
7908 | ||
7909 | *args[0].to = 0; | |
7910 | ret = kstrtoul(args[0].from, 0, &filter->offset); | |
7911 | if (ret) | |
7912 | goto fail; | |
7913 | ||
7914 | if (filter->range) { | |
7915 | *args[1].to = 0; | |
7916 | ret = kstrtoul(args[1].from, 0, &filter->size); | |
7917 | if (ret) | |
7918 | goto fail; | |
7919 | } | |
7920 | ||
7921 | if (token == IF_SRC_FILE) { | |
7922 | filename = match_strdup(&args[2]); | |
7923 | if (!filename) { | |
7924 | ret = -ENOMEM; | |
7925 | goto fail; | |
7926 | } | |
7927 | } | |
7928 | ||
7929 | state = IF_STATE_END; | |
7930 | break; | |
7931 | ||
7932 | default: | |
7933 | goto fail; | |
7934 | } | |
7935 | ||
7936 | /* | |
7937 | * Filter definition is fully parsed, validate and install it. | |
7938 | * Make sure that it doesn't contradict itself or the event's | |
7939 | * attribute. | |
7940 | */ | |
7941 | if (state == IF_STATE_END) { | |
7942 | if (kernel && event->attr.exclude_kernel) | |
7943 | goto fail; | |
7944 | ||
7945 | if (!kernel) { | |
7946 | if (!filename) | |
7947 | goto fail; | |
7948 | ||
7949 | /* look up the path and grab its inode */ | |
7950 | ret = kern_path(filename, LOOKUP_FOLLOW, &path); | |
7951 | if (ret) | |
7952 | goto fail_free_name; | |
7953 | ||
7954 | filter->inode = igrab(d_inode(path.dentry)); | |
7955 | path_put(&path); | |
7956 | kfree(filename); | |
7957 | filename = NULL; | |
7958 | ||
7959 | ret = -EINVAL; | |
7960 | if (!filter->inode || | |
7961 | !S_ISREG(filter->inode->i_mode)) | |
7962 | /* free_filters_list() will iput() */ | |
7963 | goto fail; | |
7964 | } | |
7965 | ||
7966 | /* ready to consume more filters */ | |
7967 | state = IF_STATE_ACTION; | |
7968 | filter = NULL; | |
7969 | } | |
7970 | } | |
7971 | ||
7972 | if (state != IF_STATE_ACTION) | |
7973 | goto fail; | |
7974 | ||
7975 | kfree(orig); | |
7976 | ||
7977 | return 0; | |
7978 | ||
7979 | fail_free_name: | |
7980 | kfree(filename); | |
7981 | fail: | |
7982 | free_filters_list(filters); | |
7983 | kfree(orig); | |
7984 | ||
7985 | return ret; | |
7986 | } | |
7987 | ||
7988 | static int | |
7989 | perf_event_set_addr_filter(struct perf_event *event, char *filter_str) | |
7990 | { | |
7991 | LIST_HEAD(filters); | |
7992 | int ret; | |
7993 | ||
7994 | /* | |
7995 | * Since this is called in perf_ioctl() path, we're already holding | |
7996 | * ctx::mutex. | |
7997 | */ | |
7998 | lockdep_assert_held(&event->ctx->mutex); | |
7999 | ||
8000 | if (WARN_ON_ONCE(event->parent)) | |
8001 | return -EINVAL; | |
8002 | ||
8003 | /* | |
8004 | * For now, we only support filtering in per-task events; doing so | |
8005 | * for CPU-wide events requires additional context switching trickery, | |
8006 | * since same object code will be mapped at different virtual | |
8007 | * addresses in different processes. | |
8008 | */ | |
8009 | if (!event->ctx->task) | |
8010 | return -EOPNOTSUPP; | |
8011 | ||
8012 | ret = perf_event_parse_addr_filter(event, filter_str, &filters); | |
8013 | if (ret) | |
8014 | return ret; | |
8015 | ||
8016 | ret = event->pmu->addr_filters_validate(&filters); | |
8017 | if (ret) { | |
8018 | free_filters_list(&filters); | |
8019 | return ret; | |
8020 | } | |
8021 | ||
8022 | /* remove existing filters, if any */ | |
8023 | perf_addr_filters_splice(event, &filters); | |
8024 | ||
8025 | /* install new filters */ | |
8026 | perf_event_for_each_child(event, perf_event_addr_filters_apply); | |
8027 | ||
8028 | return ret; | |
8029 | } | |
8030 | ||
c796bbbe AS |
8031 | static int perf_event_set_filter(struct perf_event *event, void __user *arg) |
8032 | { | |
8033 | char *filter_str; | |
8034 | int ret = -EINVAL; | |
8035 | ||
375637bc AS |
8036 | if ((event->attr.type != PERF_TYPE_TRACEPOINT || |
8037 | !IS_ENABLED(CONFIG_EVENT_TRACING)) && | |
8038 | !has_addr_filter(event)) | |
c796bbbe AS |
8039 | return -EINVAL; |
8040 | ||
8041 | filter_str = strndup_user(arg, PAGE_SIZE); | |
8042 | if (IS_ERR(filter_str)) | |
8043 | return PTR_ERR(filter_str); | |
8044 | ||
8045 | if (IS_ENABLED(CONFIG_EVENT_TRACING) && | |
8046 | event->attr.type == PERF_TYPE_TRACEPOINT) | |
8047 | ret = ftrace_profile_set_filter(event, event->attr.config, | |
8048 | filter_str); | |
375637bc AS |
8049 | else if (has_addr_filter(event)) |
8050 | ret = perf_event_set_addr_filter(event, filter_str); | |
c796bbbe AS |
8051 | |
8052 | kfree(filter_str); | |
8053 | return ret; | |
8054 | } | |
8055 | ||
b0a873eb PZ |
8056 | /* |
8057 | * hrtimer based swevent callback | |
8058 | */ | |
f29ac756 | 8059 | |
b0a873eb | 8060 | static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer) |
f29ac756 | 8061 | { |
b0a873eb PZ |
8062 | enum hrtimer_restart ret = HRTIMER_RESTART; |
8063 | struct perf_sample_data data; | |
8064 | struct pt_regs *regs; | |
8065 | struct perf_event *event; | |
8066 | u64 period; | |
f29ac756 | 8067 | |
b0a873eb | 8068 | event = container_of(hrtimer, struct perf_event, hw.hrtimer); |
ba3dd36c PZ |
8069 | |
8070 | if (event->state != PERF_EVENT_STATE_ACTIVE) | |
8071 | return HRTIMER_NORESTART; | |
8072 | ||
b0a873eb | 8073 | event->pmu->read(event); |
f344011c | 8074 | |
fd0d000b | 8075 | perf_sample_data_init(&data, 0, event->hw.last_period); |
b0a873eb PZ |
8076 | regs = get_irq_regs(); |
8077 | ||
8078 | if (regs && !perf_exclude_event(event, regs)) { | |
77aeeebd | 8079 | if (!(event->attr.exclude_idle && is_idle_task(current))) |
33b07b8b | 8080 | if (__perf_event_overflow(event, 1, &data, regs)) |
b0a873eb PZ |
8081 | ret = HRTIMER_NORESTART; |
8082 | } | |
24f1e32c | 8083 | |
b0a873eb PZ |
8084 | period = max_t(u64, 10000, event->hw.sample_period); |
8085 | hrtimer_forward_now(hrtimer, ns_to_ktime(period)); | |
24f1e32c | 8086 | |
b0a873eb | 8087 | return ret; |
f29ac756 PZ |
8088 | } |
8089 | ||
b0a873eb | 8090 | static void perf_swevent_start_hrtimer(struct perf_event *event) |
5c92d124 | 8091 | { |
b0a873eb | 8092 | struct hw_perf_event *hwc = &event->hw; |
5d508e82 FBH |
8093 | s64 period; |
8094 | ||
8095 | if (!is_sampling_event(event)) | |
8096 | return; | |
f5ffe02e | 8097 | |
5d508e82 FBH |
8098 | period = local64_read(&hwc->period_left); |
8099 | if (period) { | |
8100 | if (period < 0) | |
8101 | period = 10000; | |
fa407f35 | 8102 | |
5d508e82 FBH |
8103 | local64_set(&hwc->period_left, 0); |
8104 | } else { | |
8105 | period = max_t(u64, 10000, hwc->sample_period); | |
8106 | } | |
3497d206 TG |
8107 | hrtimer_start(&hwc->hrtimer, ns_to_ktime(period), |
8108 | HRTIMER_MODE_REL_PINNED); | |
24f1e32c | 8109 | } |
b0a873eb PZ |
8110 | |
8111 | static void perf_swevent_cancel_hrtimer(struct perf_event *event) | |
24f1e32c | 8112 | { |
b0a873eb PZ |
8113 | struct hw_perf_event *hwc = &event->hw; |
8114 | ||
6c7e550f | 8115 | if (is_sampling_event(event)) { |
b0a873eb | 8116 | ktime_t remaining = hrtimer_get_remaining(&hwc->hrtimer); |
fa407f35 | 8117 | local64_set(&hwc->period_left, ktime_to_ns(remaining)); |
b0a873eb PZ |
8118 | |
8119 | hrtimer_cancel(&hwc->hrtimer); | |
8120 | } | |
24f1e32c FW |
8121 | } |
8122 | ||
ba3dd36c PZ |
8123 | static void perf_swevent_init_hrtimer(struct perf_event *event) |
8124 | { | |
8125 | struct hw_perf_event *hwc = &event->hw; | |
8126 | ||
8127 | if (!is_sampling_event(event)) | |
8128 | return; | |
8129 | ||
8130 | hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); | |
8131 | hwc->hrtimer.function = perf_swevent_hrtimer; | |
8132 | ||
8133 | /* | |
8134 | * Since hrtimers have a fixed rate, we can do a static freq->period | |
8135 | * mapping and avoid the whole period adjust feedback stuff. | |
8136 | */ | |
8137 | if (event->attr.freq) { | |
8138 | long freq = event->attr.sample_freq; | |
8139 | ||
8140 | event->attr.sample_period = NSEC_PER_SEC / freq; | |
8141 | hwc->sample_period = event->attr.sample_period; | |
8142 | local64_set(&hwc->period_left, hwc->sample_period); | |
778141e3 | 8143 | hwc->last_period = hwc->sample_period; |
ba3dd36c PZ |
8144 | event->attr.freq = 0; |
8145 | } | |
8146 | } | |
8147 | ||
b0a873eb PZ |
8148 | /* |
8149 | * Software event: cpu wall time clock | |
8150 | */ | |
8151 | ||
8152 | static void cpu_clock_event_update(struct perf_event *event) | |
24f1e32c | 8153 | { |
b0a873eb PZ |
8154 | s64 prev; |
8155 | u64 now; | |
8156 | ||
a4eaf7f1 | 8157 | now = local_clock(); |
b0a873eb PZ |
8158 | prev = local64_xchg(&event->hw.prev_count, now); |
8159 | local64_add(now - prev, &event->count); | |
24f1e32c | 8160 | } |
24f1e32c | 8161 | |
a4eaf7f1 | 8162 | static void cpu_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 8163 | { |
a4eaf7f1 | 8164 | local64_set(&event->hw.prev_count, local_clock()); |
b0a873eb | 8165 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
8166 | } |
8167 | ||
a4eaf7f1 | 8168 | static void cpu_clock_event_stop(struct perf_event *event, int flags) |
f29ac756 | 8169 | { |
b0a873eb PZ |
8170 | perf_swevent_cancel_hrtimer(event); |
8171 | cpu_clock_event_update(event); | |
8172 | } | |
f29ac756 | 8173 | |
a4eaf7f1 PZ |
8174 | static int cpu_clock_event_add(struct perf_event *event, int flags) |
8175 | { | |
8176 | if (flags & PERF_EF_START) | |
8177 | cpu_clock_event_start(event, flags); | |
6a694a60 | 8178 | perf_event_update_userpage(event); |
a4eaf7f1 PZ |
8179 | |
8180 | return 0; | |
8181 | } | |
8182 | ||
8183 | static void cpu_clock_event_del(struct perf_event *event, int flags) | |
8184 | { | |
8185 | cpu_clock_event_stop(event, flags); | |
8186 | } | |
8187 | ||
b0a873eb PZ |
8188 | static void cpu_clock_event_read(struct perf_event *event) |
8189 | { | |
8190 | cpu_clock_event_update(event); | |
8191 | } | |
f344011c | 8192 | |
b0a873eb PZ |
8193 | static int cpu_clock_event_init(struct perf_event *event) |
8194 | { | |
8195 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
8196 | return -ENOENT; | |
8197 | ||
8198 | if (event->attr.config != PERF_COUNT_SW_CPU_CLOCK) | |
8199 | return -ENOENT; | |
8200 | ||
2481c5fa SE |
8201 | /* |
8202 | * no branch sampling for software events | |
8203 | */ | |
8204 | if (has_branch_stack(event)) | |
8205 | return -EOPNOTSUPP; | |
8206 | ||
ba3dd36c PZ |
8207 | perf_swevent_init_hrtimer(event); |
8208 | ||
b0a873eb | 8209 | return 0; |
f29ac756 PZ |
8210 | } |
8211 | ||
b0a873eb | 8212 | static struct pmu perf_cpu_clock = { |
89a1e187 PZ |
8213 | .task_ctx_nr = perf_sw_context, |
8214 | ||
34f43927 PZ |
8215 | .capabilities = PERF_PMU_CAP_NO_NMI, |
8216 | ||
b0a873eb | 8217 | .event_init = cpu_clock_event_init, |
a4eaf7f1 PZ |
8218 | .add = cpu_clock_event_add, |
8219 | .del = cpu_clock_event_del, | |
8220 | .start = cpu_clock_event_start, | |
8221 | .stop = cpu_clock_event_stop, | |
b0a873eb PZ |
8222 | .read = cpu_clock_event_read, |
8223 | }; | |
8224 | ||
8225 | /* | |
8226 | * Software event: task time clock | |
8227 | */ | |
8228 | ||
8229 | static void task_clock_event_update(struct perf_event *event, u64 now) | |
5c92d124 | 8230 | { |
b0a873eb PZ |
8231 | u64 prev; |
8232 | s64 delta; | |
5c92d124 | 8233 | |
b0a873eb PZ |
8234 | prev = local64_xchg(&event->hw.prev_count, now); |
8235 | delta = now - prev; | |
8236 | local64_add(delta, &event->count); | |
8237 | } | |
5c92d124 | 8238 | |
a4eaf7f1 | 8239 | static void task_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 8240 | { |
a4eaf7f1 | 8241 | local64_set(&event->hw.prev_count, event->ctx->time); |
b0a873eb | 8242 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
8243 | } |
8244 | ||
a4eaf7f1 | 8245 | static void task_clock_event_stop(struct perf_event *event, int flags) |
b0a873eb PZ |
8246 | { |
8247 | perf_swevent_cancel_hrtimer(event); | |
8248 | task_clock_event_update(event, event->ctx->time); | |
a4eaf7f1 PZ |
8249 | } |
8250 | ||
8251 | static int task_clock_event_add(struct perf_event *event, int flags) | |
8252 | { | |
8253 | if (flags & PERF_EF_START) | |
8254 | task_clock_event_start(event, flags); | |
6a694a60 | 8255 | perf_event_update_userpage(event); |
b0a873eb | 8256 | |
a4eaf7f1 PZ |
8257 | return 0; |
8258 | } | |
8259 | ||
8260 | static void task_clock_event_del(struct perf_event *event, int flags) | |
8261 | { | |
8262 | task_clock_event_stop(event, PERF_EF_UPDATE); | |
b0a873eb PZ |
8263 | } |
8264 | ||
8265 | static void task_clock_event_read(struct perf_event *event) | |
8266 | { | |
768a06e2 PZ |
8267 | u64 now = perf_clock(); |
8268 | u64 delta = now - event->ctx->timestamp; | |
8269 | u64 time = event->ctx->time + delta; | |
b0a873eb PZ |
8270 | |
8271 | task_clock_event_update(event, time); | |
8272 | } | |
8273 | ||
8274 | static int task_clock_event_init(struct perf_event *event) | |
6fb2915d | 8275 | { |
b0a873eb PZ |
8276 | if (event->attr.type != PERF_TYPE_SOFTWARE) |
8277 | return -ENOENT; | |
8278 | ||
8279 | if (event->attr.config != PERF_COUNT_SW_TASK_CLOCK) | |
8280 | return -ENOENT; | |
8281 | ||
2481c5fa SE |
8282 | /* |
8283 | * no branch sampling for software events | |
8284 | */ | |
8285 | if (has_branch_stack(event)) | |
8286 | return -EOPNOTSUPP; | |
8287 | ||
ba3dd36c PZ |
8288 | perf_swevent_init_hrtimer(event); |
8289 | ||
b0a873eb | 8290 | return 0; |
6fb2915d LZ |
8291 | } |
8292 | ||
b0a873eb | 8293 | static struct pmu perf_task_clock = { |
89a1e187 PZ |
8294 | .task_ctx_nr = perf_sw_context, |
8295 | ||
34f43927 PZ |
8296 | .capabilities = PERF_PMU_CAP_NO_NMI, |
8297 | ||
b0a873eb | 8298 | .event_init = task_clock_event_init, |
a4eaf7f1 PZ |
8299 | .add = task_clock_event_add, |
8300 | .del = task_clock_event_del, | |
8301 | .start = task_clock_event_start, | |
8302 | .stop = task_clock_event_stop, | |
b0a873eb PZ |
8303 | .read = task_clock_event_read, |
8304 | }; | |
6fb2915d | 8305 | |
ad5133b7 | 8306 | static void perf_pmu_nop_void(struct pmu *pmu) |
e077df4f | 8307 | { |
e077df4f | 8308 | } |
6fb2915d | 8309 | |
fbbe0701 SB |
8310 | static void perf_pmu_nop_txn(struct pmu *pmu, unsigned int flags) |
8311 | { | |
8312 | } | |
8313 | ||
ad5133b7 | 8314 | static int perf_pmu_nop_int(struct pmu *pmu) |
6fb2915d | 8315 | { |
ad5133b7 | 8316 | return 0; |
6fb2915d LZ |
8317 | } |
8318 | ||
18ab2cd3 | 8319 | static DEFINE_PER_CPU(unsigned int, nop_txn_flags); |
fbbe0701 SB |
8320 | |
8321 | static void perf_pmu_start_txn(struct pmu *pmu, unsigned int flags) | |
6fb2915d | 8322 | { |
fbbe0701 SB |
8323 | __this_cpu_write(nop_txn_flags, flags); |
8324 | ||
8325 | if (flags & ~PERF_PMU_TXN_ADD) | |
8326 | return; | |
8327 | ||
ad5133b7 | 8328 | perf_pmu_disable(pmu); |
6fb2915d LZ |
8329 | } |
8330 | ||
ad5133b7 PZ |
8331 | static int perf_pmu_commit_txn(struct pmu *pmu) |
8332 | { | |
fbbe0701 SB |
8333 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
8334 | ||
8335 | __this_cpu_write(nop_txn_flags, 0); | |
8336 | ||
8337 | if (flags & ~PERF_PMU_TXN_ADD) | |
8338 | return 0; | |
8339 | ||
ad5133b7 PZ |
8340 | perf_pmu_enable(pmu); |
8341 | return 0; | |
8342 | } | |
e077df4f | 8343 | |
ad5133b7 | 8344 | static void perf_pmu_cancel_txn(struct pmu *pmu) |
24f1e32c | 8345 | { |
fbbe0701 SB |
8346 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
8347 | ||
8348 | __this_cpu_write(nop_txn_flags, 0); | |
8349 | ||
8350 | if (flags & ~PERF_PMU_TXN_ADD) | |
8351 | return; | |
8352 | ||
ad5133b7 | 8353 | perf_pmu_enable(pmu); |
24f1e32c FW |
8354 | } |
8355 | ||
35edc2a5 PZ |
8356 | static int perf_event_idx_default(struct perf_event *event) |
8357 | { | |
c719f560 | 8358 | return 0; |
35edc2a5 PZ |
8359 | } |
8360 | ||
8dc85d54 PZ |
8361 | /* |
8362 | * Ensures all contexts with the same task_ctx_nr have the same | |
8363 | * pmu_cpu_context too. | |
8364 | */ | |
9e317041 | 8365 | static struct perf_cpu_context __percpu *find_pmu_context(int ctxn) |
24f1e32c | 8366 | { |
8dc85d54 | 8367 | struct pmu *pmu; |
b326e956 | 8368 | |
8dc85d54 PZ |
8369 | if (ctxn < 0) |
8370 | return NULL; | |
24f1e32c | 8371 | |
8dc85d54 PZ |
8372 | list_for_each_entry(pmu, &pmus, entry) { |
8373 | if (pmu->task_ctx_nr == ctxn) | |
8374 | return pmu->pmu_cpu_context; | |
8375 | } | |
24f1e32c | 8376 | |
8dc85d54 | 8377 | return NULL; |
24f1e32c FW |
8378 | } |
8379 | ||
51676957 | 8380 | static void update_pmu_context(struct pmu *pmu, struct pmu *old_pmu) |
24f1e32c | 8381 | { |
51676957 PZ |
8382 | int cpu; |
8383 | ||
8384 | for_each_possible_cpu(cpu) { | |
8385 | struct perf_cpu_context *cpuctx; | |
8386 | ||
8387 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
8388 | ||
3f1f3320 PZ |
8389 | if (cpuctx->unique_pmu == old_pmu) |
8390 | cpuctx->unique_pmu = pmu; | |
51676957 PZ |
8391 | } |
8392 | } | |
8393 | ||
8394 | static void free_pmu_context(struct pmu *pmu) | |
8395 | { | |
8396 | struct pmu *i; | |
f5ffe02e | 8397 | |
8dc85d54 | 8398 | mutex_lock(&pmus_lock); |
0475f9ea | 8399 | /* |
8dc85d54 | 8400 | * Like a real lame refcount. |
0475f9ea | 8401 | */ |
51676957 PZ |
8402 | list_for_each_entry(i, &pmus, entry) { |
8403 | if (i->pmu_cpu_context == pmu->pmu_cpu_context) { | |
8404 | update_pmu_context(i, pmu); | |
8dc85d54 | 8405 | goto out; |
51676957 | 8406 | } |
8dc85d54 | 8407 | } |
d6d020e9 | 8408 | |
51676957 | 8409 | free_percpu(pmu->pmu_cpu_context); |
8dc85d54 PZ |
8410 | out: |
8411 | mutex_unlock(&pmus_lock); | |
24f1e32c | 8412 | } |
6e855cd4 AS |
8413 | |
8414 | /* | |
8415 | * Let userspace know that this PMU supports address range filtering: | |
8416 | */ | |
8417 | static ssize_t nr_addr_filters_show(struct device *dev, | |
8418 | struct device_attribute *attr, | |
8419 | char *page) | |
8420 | { | |
8421 | struct pmu *pmu = dev_get_drvdata(dev); | |
8422 | ||
8423 | return snprintf(page, PAGE_SIZE - 1, "%d\n", pmu->nr_addr_filters); | |
8424 | } | |
8425 | DEVICE_ATTR_RO(nr_addr_filters); | |
8426 | ||
2e80a82a | 8427 | static struct idr pmu_idr; |
d6d020e9 | 8428 | |
abe43400 PZ |
8429 | static ssize_t |
8430 | type_show(struct device *dev, struct device_attribute *attr, char *page) | |
8431 | { | |
8432 | struct pmu *pmu = dev_get_drvdata(dev); | |
8433 | ||
8434 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->type); | |
8435 | } | |
90826ca7 | 8436 | static DEVICE_ATTR_RO(type); |
abe43400 | 8437 | |
62b85639 SE |
8438 | static ssize_t |
8439 | perf_event_mux_interval_ms_show(struct device *dev, | |
8440 | struct device_attribute *attr, | |
8441 | char *page) | |
8442 | { | |
8443 | struct pmu *pmu = dev_get_drvdata(dev); | |
8444 | ||
8445 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->hrtimer_interval_ms); | |
8446 | } | |
8447 | ||
272325c4 PZ |
8448 | static DEFINE_MUTEX(mux_interval_mutex); |
8449 | ||
62b85639 SE |
8450 | static ssize_t |
8451 | perf_event_mux_interval_ms_store(struct device *dev, | |
8452 | struct device_attribute *attr, | |
8453 | const char *buf, size_t count) | |
8454 | { | |
8455 | struct pmu *pmu = dev_get_drvdata(dev); | |
8456 | int timer, cpu, ret; | |
8457 | ||
8458 | ret = kstrtoint(buf, 0, &timer); | |
8459 | if (ret) | |
8460 | return ret; | |
8461 | ||
8462 | if (timer < 1) | |
8463 | return -EINVAL; | |
8464 | ||
8465 | /* same value, noting to do */ | |
8466 | if (timer == pmu->hrtimer_interval_ms) | |
8467 | return count; | |
8468 | ||
272325c4 | 8469 | mutex_lock(&mux_interval_mutex); |
62b85639 SE |
8470 | pmu->hrtimer_interval_ms = timer; |
8471 | ||
8472 | /* update all cpuctx for this PMU */ | |
272325c4 PZ |
8473 | get_online_cpus(); |
8474 | for_each_online_cpu(cpu) { | |
62b85639 SE |
8475 | struct perf_cpu_context *cpuctx; |
8476 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
8477 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * timer); | |
8478 | ||
272325c4 PZ |
8479 | cpu_function_call(cpu, |
8480 | (remote_function_f)perf_mux_hrtimer_restart, cpuctx); | |
62b85639 | 8481 | } |
272325c4 PZ |
8482 | put_online_cpus(); |
8483 | mutex_unlock(&mux_interval_mutex); | |
62b85639 SE |
8484 | |
8485 | return count; | |
8486 | } | |
90826ca7 | 8487 | static DEVICE_ATTR_RW(perf_event_mux_interval_ms); |
62b85639 | 8488 | |
90826ca7 GKH |
8489 | static struct attribute *pmu_dev_attrs[] = { |
8490 | &dev_attr_type.attr, | |
8491 | &dev_attr_perf_event_mux_interval_ms.attr, | |
8492 | NULL, | |
abe43400 | 8493 | }; |
90826ca7 | 8494 | ATTRIBUTE_GROUPS(pmu_dev); |
abe43400 PZ |
8495 | |
8496 | static int pmu_bus_running; | |
8497 | static struct bus_type pmu_bus = { | |
8498 | .name = "event_source", | |
90826ca7 | 8499 | .dev_groups = pmu_dev_groups, |
abe43400 PZ |
8500 | }; |
8501 | ||
8502 | static void pmu_dev_release(struct device *dev) | |
8503 | { | |
8504 | kfree(dev); | |
8505 | } | |
8506 | ||
8507 | static int pmu_dev_alloc(struct pmu *pmu) | |
8508 | { | |
8509 | int ret = -ENOMEM; | |
8510 | ||
8511 | pmu->dev = kzalloc(sizeof(struct device), GFP_KERNEL); | |
8512 | if (!pmu->dev) | |
8513 | goto out; | |
8514 | ||
0c9d42ed | 8515 | pmu->dev->groups = pmu->attr_groups; |
abe43400 PZ |
8516 | device_initialize(pmu->dev); |
8517 | ret = dev_set_name(pmu->dev, "%s", pmu->name); | |
8518 | if (ret) | |
8519 | goto free_dev; | |
8520 | ||
8521 | dev_set_drvdata(pmu->dev, pmu); | |
8522 | pmu->dev->bus = &pmu_bus; | |
8523 | pmu->dev->release = pmu_dev_release; | |
8524 | ret = device_add(pmu->dev); | |
8525 | if (ret) | |
8526 | goto free_dev; | |
8527 | ||
6e855cd4 AS |
8528 | /* For PMUs with address filters, throw in an extra attribute: */ |
8529 | if (pmu->nr_addr_filters) | |
8530 | ret = device_create_file(pmu->dev, &dev_attr_nr_addr_filters); | |
8531 | ||
8532 | if (ret) | |
8533 | goto del_dev; | |
8534 | ||
abe43400 PZ |
8535 | out: |
8536 | return ret; | |
8537 | ||
6e855cd4 AS |
8538 | del_dev: |
8539 | device_del(pmu->dev); | |
8540 | ||
abe43400 PZ |
8541 | free_dev: |
8542 | put_device(pmu->dev); | |
8543 | goto out; | |
8544 | } | |
8545 | ||
547e9fd7 | 8546 | static struct lock_class_key cpuctx_mutex; |
facc4307 | 8547 | static struct lock_class_key cpuctx_lock; |
547e9fd7 | 8548 | |
03d8e80b | 8549 | int perf_pmu_register(struct pmu *pmu, const char *name, int type) |
24f1e32c | 8550 | { |
108b02cf | 8551 | int cpu, ret; |
24f1e32c | 8552 | |
b0a873eb | 8553 | mutex_lock(&pmus_lock); |
33696fc0 PZ |
8554 | ret = -ENOMEM; |
8555 | pmu->pmu_disable_count = alloc_percpu(int); | |
8556 | if (!pmu->pmu_disable_count) | |
8557 | goto unlock; | |
f29ac756 | 8558 | |
2e80a82a PZ |
8559 | pmu->type = -1; |
8560 | if (!name) | |
8561 | goto skip_type; | |
8562 | pmu->name = name; | |
8563 | ||
8564 | if (type < 0) { | |
0e9c3be2 TH |
8565 | type = idr_alloc(&pmu_idr, pmu, PERF_TYPE_MAX, 0, GFP_KERNEL); |
8566 | if (type < 0) { | |
8567 | ret = type; | |
2e80a82a PZ |
8568 | goto free_pdc; |
8569 | } | |
8570 | } | |
8571 | pmu->type = type; | |
8572 | ||
abe43400 PZ |
8573 | if (pmu_bus_running) { |
8574 | ret = pmu_dev_alloc(pmu); | |
8575 | if (ret) | |
8576 | goto free_idr; | |
8577 | } | |
8578 | ||
2e80a82a | 8579 | skip_type: |
26657848 PZ |
8580 | if (pmu->task_ctx_nr == perf_hw_context) { |
8581 | static int hw_context_taken = 0; | |
8582 | ||
5101ef20 MR |
8583 | /* |
8584 | * Other than systems with heterogeneous CPUs, it never makes | |
8585 | * sense for two PMUs to share perf_hw_context. PMUs which are | |
8586 | * uncore must use perf_invalid_context. | |
8587 | */ | |
8588 | if (WARN_ON_ONCE(hw_context_taken && | |
8589 | !(pmu->capabilities & PERF_PMU_CAP_HETEROGENEOUS_CPUS))) | |
26657848 PZ |
8590 | pmu->task_ctx_nr = perf_invalid_context; |
8591 | ||
8592 | hw_context_taken = 1; | |
8593 | } | |
8594 | ||
8dc85d54 PZ |
8595 | pmu->pmu_cpu_context = find_pmu_context(pmu->task_ctx_nr); |
8596 | if (pmu->pmu_cpu_context) | |
8597 | goto got_cpu_context; | |
f29ac756 | 8598 | |
c4814202 | 8599 | ret = -ENOMEM; |
108b02cf PZ |
8600 | pmu->pmu_cpu_context = alloc_percpu(struct perf_cpu_context); |
8601 | if (!pmu->pmu_cpu_context) | |
abe43400 | 8602 | goto free_dev; |
f344011c | 8603 | |
108b02cf PZ |
8604 | for_each_possible_cpu(cpu) { |
8605 | struct perf_cpu_context *cpuctx; | |
8606 | ||
8607 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
eb184479 | 8608 | __perf_event_init_context(&cpuctx->ctx); |
547e9fd7 | 8609 | lockdep_set_class(&cpuctx->ctx.mutex, &cpuctx_mutex); |
facc4307 | 8610 | lockdep_set_class(&cpuctx->ctx.lock, &cpuctx_lock); |
108b02cf | 8611 | cpuctx->ctx.pmu = pmu; |
9e630205 | 8612 | |
272325c4 | 8613 | __perf_mux_hrtimer_init(cpuctx, cpu); |
9e630205 | 8614 | |
3f1f3320 | 8615 | cpuctx->unique_pmu = pmu; |
108b02cf | 8616 | } |
76e1d904 | 8617 | |
8dc85d54 | 8618 | got_cpu_context: |
ad5133b7 PZ |
8619 | if (!pmu->start_txn) { |
8620 | if (pmu->pmu_enable) { | |
8621 | /* | |
8622 | * If we have pmu_enable/pmu_disable calls, install | |
8623 | * transaction stubs that use that to try and batch | |
8624 | * hardware accesses. | |
8625 | */ | |
8626 | pmu->start_txn = perf_pmu_start_txn; | |
8627 | pmu->commit_txn = perf_pmu_commit_txn; | |
8628 | pmu->cancel_txn = perf_pmu_cancel_txn; | |
8629 | } else { | |
fbbe0701 | 8630 | pmu->start_txn = perf_pmu_nop_txn; |
ad5133b7 PZ |
8631 | pmu->commit_txn = perf_pmu_nop_int; |
8632 | pmu->cancel_txn = perf_pmu_nop_void; | |
f344011c | 8633 | } |
5c92d124 | 8634 | } |
15dbf27c | 8635 | |
ad5133b7 PZ |
8636 | if (!pmu->pmu_enable) { |
8637 | pmu->pmu_enable = perf_pmu_nop_void; | |
8638 | pmu->pmu_disable = perf_pmu_nop_void; | |
8639 | } | |
8640 | ||
35edc2a5 PZ |
8641 | if (!pmu->event_idx) |
8642 | pmu->event_idx = perf_event_idx_default; | |
8643 | ||
b0a873eb | 8644 | list_add_rcu(&pmu->entry, &pmus); |
bed5b25a | 8645 | atomic_set(&pmu->exclusive_cnt, 0); |
33696fc0 PZ |
8646 | ret = 0; |
8647 | unlock: | |
b0a873eb PZ |
8648 | mutex_unlock(&pmus_lock); |
8649 | ||
33696fc0 | 8650 | return ret; |
108b02cf | 8651 | |
abe43400 PZ |
8652 | free_dev: |
8653 | device_del(pmu->dev); | |
8654 | put_device(pmu->dev); | |
8655 | ||
2e80a82a PZ |
8656 | free_idr: |
8657 | if (pmu->type >= PERF_TYPE_MAX) | |
8658 | idr_remove(&pmu_idr, pmu->type); | |
8659 | ||
108b02cf PZ |
8660 | free_pdc: |
8661 | free_percpu(pmu->pmu_disable_count); | |
8662 | goto unlock; | |
f29ac756 | 8663 | } |
c464c76e | 8664 | EXPORT_SYMBOL_GPL(perf_pmu_register); |
f29ac756 | 8665 | |
b0a873eb | 8666 | void perf_pmu_unregister(struct pmu *pmu) |
5c92d124 | 8667 | { |
b0a873eb PZ |
8668 | mutex_lock(&pmus_lock); |
8669 | list_del_rcu(&pmu->entry); | |
8670 | mutex_unlock(&pmus_lock); | |
5c92d124 | 8671 | |
0475f9ea | 8672 | /* |
cde8e884 PZ |
8673 | * We dereference the pmu list under both SRCU and regular RCU, so |
8674 | * synchronize against both of those. | |
0475f9ea | 8675 | */ |
b0a873eb | 8676 | synchronize_srcu(&pmus_srcu); |
cde8e884 | 8677 | synchronize_rcu(); |
d6d020e9 | 8678 | |
33696fc0 | 8679 | free_percpu(pmu->pmu_disable_count); |
2e80a82a PZ |
8680 | if (pmu->type >= PERF_TYPE_MAX) |
8681 | idr_remove(&pmu_idr, pmu->type); | |
6e855cd4 AS |
8682 | if (pmu->nr_addr_filters) |
8683 | device_remove_file(pmu->dev, &dev_attr_nr_addr_filters); | |
abe43400 PZ |
8684 | device_del(pmu->dev); |
8685 | put_device(pmu->dev); | |
51676957 | 8686 | free_pmu_context(pmu); |
b0a873eb | 8687 | } |
c464c76e | 8688 | EXPORT_SYMBOL_GPL(perf_pmu_unregister); |
d6d020e9 | 8689 | |
cc34b98b MR |
8690 | static int perf_try_init_event(struct pmu *pmu, struct perf_event *event) |
8691 | { | |
ccd41c86 | 8692 | struct perf_event_context *ctx = NULL; |
cc34b98b MR |
8693 | int ret; |
8694 | ||
8695 | if (!try_module_get(pmu->module)) | |
8696 | return -ENODEV; | |
ccd41c86 PZ |
8697 | |
8698 | if (event->group_leader != event) { | |
8b10c5e2 PZ |
8699 | /* |
8700 | * This ctx->mutex can nest when we're called through | |
8701 | * inheritance. See the perf_event_ctx_lock_nested() comment. | |
8702 | */ | |
8703 | ctx = perf_event_ctx_lock_nested(event->group_leader, | |
8704 | SINGLE_DEPTH_NESTING); | |
ccd41c86 PZ |
8705 | BUG_ON(!ctx); |
8706 | } | |
8707 | ||
cc34b98b MR |
8708 | event->pmu = pmu; |
8709 | ret = pmu->event_init(event); | |
ccd41c86 PZ |
8710 | |
8711 | if (ctx) | |
8712 | perf_event_ctx_unlock(event->group_leader, ctx); | |
8713 | ||
cc34b98b MR |
8714 | if (ret) |
8715 | module_put(pmu->module); | |
8716 | ||
8717 | return ret; | |
8718 | } | |
8719 | ||
18ab2cd3 | 8720 | static struct pmu *perf_init_event(struct perf_event *event) |
b0a873eb PZ |
8721 | { |
8722 | struct pmu *pmu = NULL; | |
8723 | int idx; | |
940c5b29 | 8724 | int ret; |
b0a873eb PZ |
8725 | |
8726 | idx = srcu_read_lock(&pmus_srcu); | |
2e80a82a PZ |
8727 | |
8728 | rcu_read_lock(); | |
8729 | pmu = idr_find(&pmu_idr, event->attr.type); | |
8730 | rcu_read_unlock(); | |
940c5b29 | 8731 | if (pmu) { |
cc34b98b | 8732 | ret = perf_try_init_event(pmu, event); |
940c5b29 LM |
8733 | if (ret) |
8734 | pmu = ERR_PTR(ret); | |
2e80a82a | 8735 | goto unlock; |
940c5b29 | 8736 | } |
2e80a82a | 8737 | |
b0a873eb | 8738 | list_for_each_entry_rcu(pmu, &pmus, entry) { |
cc34b98b | 8739 | ret = perf_try_init_event(pmu, event); |
b0a873eb | 8740 | if (!ret) |
e5f4d339 | 8741 | goto unlock; |
76e1d904 | 8742 | |
b0a873eb PZ |
8743 | if (ret != -ENOENT) { |
8744 | pmu = ERR_PTR(ret); | |
e5f4d339 | 8745 | goto unlock; |
f344011c | 8746 | } |
5c92d124 | 8747 | } |
e5f4d339 PZ |
8748 | pmu = ERR_PTR(-ENOENT); |
8749 | unlock: | |
b0a873eb | 8750 | srcu_read_unlock(&pmus_srcu, idx); |
15dbf27c | 8751 | |
4aeb0b42 | 8752 | return pmu; |
5c92d124 IM |
8753 | } |
8754 | ||
f2fb6bef KL |
8755 | static void attach_sb_event(struct perf_event *event) |
8756 | { | |
8757 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
8758 | ||
8759 | raw_spin_lock(&pel->lock); | |
8760 | list_add_rcu(&event->sb_list, &pel->list); | |
8761 | raw_spin_unlock(&pel->lock); | |
8762 | } | |
8763 | ||
aab5b71e PZ |
8764 | /* |
8765 | * We keep a list of all !task (and therefore per-cpu) events | |
8766 | * that need to receive side-band records. | |
8767 | * | |
8768 | * This avoids having to scan all the various PMU per-cpu contexts | |
8769 | * looking for them. | |
8770 | */ | |
f2fb6bef KL |
8771 | static void account_pmu_sb_event(struct perf_event *event) |
8772 | { | |
a4f144eb | 8773 | if (is_sb_event(event)) |
f2fb6bef KL |
8774 | attach_sb_event(event); |
8775 | } | |
8776 | ||
4beb31f3 FW |
8777 | static void account_event_cpu(struct perf_event *event, int cpu) |
8778 | { | |
8779 | if (event->parent) | |
8780 | return; | |
8781 | ||
4beb31f3 FW |
8782 | if (is_cgroup_event(event)) |
8783 | atomic_inc(&per_cpu(perf_cgroup_events, cpu)); | |
8784 | } | |
8785 | ||
555e0c1e FW |
8786 | /* Freq events need the tick to stay alive (see perf_event_task_tick). */ |
8787 | static void account_freq_event_nohz(void) | |
8788 | { | |
8789 | #ifdef CONFIG_NO_HZ_FULL | |
8790 | /* Lock so we don't race with concurrent unaccount */ | |
8791 | spin_lock(&nr_freq_lock); | |
8792 | if (atomic_inc_return(&nr_freq_events) == 1) | |
8793 | tick_nohz_dep_set(TICK_DEP_BIT_PERF_EVENTS); | |
8794 | spin_unlock(&nr_freq_lock); | |
8795 | #endif | |
8796 | } | |
8797 | ||
8798 | static void account_freq_event(void) | |
8799 | { | |
8800 | if (tick_nohz_full_enabled()) | |
8801 | account_freq_event_nohz(); | |
8802 | else | |
8803 | atomic_inc(&nr_freq_events); | |
8804 | } | |
8805 | ||
8806 | ||
766d6c07 FW |
8807 | static void account_event(struct perf_event *event) |
8808 | { | |
25432ae9 PZ |
8809 | bool inc = false; |
8810 | ||
4beb31f3 FW |
8811 | if (event->parent) |
8812 | return; | |
8813 | ||
766d6c07 | 8814 | if (event->attach_state & PERF_ATTACH_TASK) |
25432ae9 | 8815 | inc = true; |
766d6c07 FW |
8816 | if (event->attr.mmap || event->attr.mmap_data) |
8817 | atomic_inc(&nr_mmap_events); | |
8818 | if (event->attr.comm) | |
8819 | atomic_inc(&nr_comm_events); | |
8820 | if (event->attr.task) | |
8821 | atomic_inc(&nr_task_events); | |
555e0c1e FW |
8822 | if (event->attr.freq) |
8823 | account_freq_event(); | |
45ac1403 AH |
8824 | if (event->attr.context_switch) { |
8825 | atomic_inc(&nr_switch_events); | |
25432ae9 | 8826 | inc = true; |
45ac1403 | 8827 | } |
4beb31f3 | 8828 | if (has_branch_stack(event)) |
25432ae9 | 8829 | inc = true; |
4beb31f3 | 8830 | if (is_cgroup_event(event)) |
25432ae9 PZ |
8831 | inc = true; |
8832 | ||
9107c89e PZ |
8833 | if (inc) { |
8834 | if (atomic_inc_not_zero(&perf_sched_count)) | |
8835 | goto enabled; | |
8836 | ||
8837 | mutex_lock(&perf_sched_mutex); | |
8838 | if (!atomic_read(&perf_sched_count)) { | |
8839 | static_branch_enable(&perf_sched_events); | |
8840 | /* | |
8841 | * Guarantee that all CPUs observe they key change and | |
8842 | * call the perf scheduling hooks before proceeding to | |
8843 | * install events that need them. | |
8844 | */ | |
8845 | synchronize_sched(); | |
8846 | } | |
8847 | /* | |
8848 | * Now that we have waited for the sync_sched(), allow further | |
8849 | * increments to by-pass the mutex. | |
8850 | */ | |
8851 | atomic_inc(&perf_sched_count); | |
8852 | mutex_unlock(&perf_sched_mutex); | |
8853 | } | |
8854 | enabled: | |
4beb31f3 FW |
8855 | |
8856 | account_event_cpu(event, event->cpu); | |
f2fb6bef KL |
8857 | |
8858 | account_pmu_sb_event(event); | |
766d6c07 FW |
8859 | } |
8860 | ||
0793a61d | 8861 | /* |
cdd6c482 | 8862 | * Allocate and initialize a event structure |
0793a61d | 8863 | */ |
cdd6c482 | 8864 | static struct perf_event * |
c3f00c70 | 8865 | perf_event_alloc(struct perf_event_attr *attr, int cpu, |
d580ff86 PZ |
8866 | struct task_struct *task, |
8867 | struct perf_event *group_leader, | |
8868 | struct perf_event *parent_event, | |
4dc0da86 | 8869 | perf_overflow_handler_t overflow_handler, |
79dff51e | 8870 | void *context, int cgroup_fd) |
0793a61d | 8871 | { |
51b0fe39 | 8872 | struct pmu *pmu; |
cdd6c482 IM |
8873 | struct perf_event *event; |
8874 | struct hw_perf_event *hwc; | |
90983b16 | 8875 | long err = -EINVAL; |
0793a61d | 8876 | |
66832eb4 ON |
8877 | if ((unsigned)cpu >= nr_cpu_ids) { |
8878 | if (!task || cpu != -1) | |
8879 | return ERR_PTR(-EINVAL); | |
8880 | } | |
8881 | ||
c3f00c70 | 8882 | event = kzalloc(sizeof(*event), GFP_KERNEL); |
cdd6c482 | 8883 | if (!event) |
d5d2bc0d | 8884 | return ERR_PTR(-ENOMEM); |
0793a61d | 8885 | |
04289bb9 | 8886 | /* |
cdd6c482 | 8887 | * Single events are their own group leaders, with an |
04289bb9 IM |
8888 | * empty sibling list: |
8889 | */ | |
8890 | if (!group_leader) | |
cdd6c482 | 8891 | group_leader = event; |
04289bb9 | 8892 | |
cdd6c482 IM |
8893 | mutex_init(&event->child_mutex); |
8894 | INIT_LIST_HEAD(&event->child_list); | |
fccc714b | 8895 | |
cdd6c482 IM |
8896 | INIT_LIST_HEAD(&event->group_entry); |
8897 | INIT_LIST_HEAD(&event->event_entry); | |
8898 | INIT_LIST_HEAD(&event->sibling_list); | |
10c6db11 | 8899 | INIT_LIST_HEAD(&event->rb_entry); |
71ad88ef | 8900 | INIT_LIST_HEAD(&event->active_entry); |
375637bc | 8901 | INIT_LIST_HEAD(&event->addr_filters.list); |
f3ae75de SE |
8902 | INIT_HLIST_NODE(&event->hlist_entry); |
8903 | ||
10c6db11 | 8904 | |
cdd6c482 | 8905 | init_waitqueue_head(&event->waitq); |
e360adbe | 8906 | init_irq_work(&event->pending, perf_pending_event); |
0793a61d | 8907 | |
cdd6c482 | 8908 | mutex_init(&event->mmap_mutex); |
375637bc | 8909 | raw_spin_lock_init(&event->addr_filters.lock); |
7b732a75 | 8910 | |
a6fa941d | 8911 | atomic_long_set(&event->refcount, 1); |
cdd6c482 IM |
8912 | event->cpu = cpu; |
8913 | event->attr = *attr; | |
8914 | event->group_leader = group_leader; | |
8915 | event->pmu = NULL; | |
cdd6c482 | 8916 | event->oncpu = -1; |
a96bbc16 | 8917 | |
cdd6c482 | 8918 | event->parent = parent_event; |
b84fbc9f | 8919 | |
17cf22c3 | 8920 | event->ns = get_pid_ns(task_active_pid_ns(current)); |
cdd6c482 | 8921 | event->id = atomic64_inc_return(&perf_event_id); |
a96bbc16 | 8922 | |
cdd6c482 | 8923 | event->state = PERF_EVENT_STATE_INACTIVE; |
329d876d | 8924 | |
d580ff86 PZ |
8925 | if (task) { |
8926 | event->attach_state = PERF_ATTACH_TASK; | |
d580ff86 | 8927 | /* |
50f16a8b PZ |
8928 | * XXX pmu::event_init needs to know what task to account to |
8929 | * and we cannot use the ctx information because we need the | |
8930 | * pmu before we get a ctx. | |
d580ff86 | 8931 | */ |
50f16a8b | 8932 | event->hw.target = task; |
d580ff86 PZ |
8933 | } |
8934 | ||
34f43927 PZ |
8935 | event->clock = &local_clock; |
8936 | if (parent_event) | |
8937 | event->clock = parent_event->clock; | |
8938 | ||
4dc0da86 | 8939 | if (!overflow_handler && parent_event) { |
b326e956 | 8940 | overflow_handler = parent_event->overflow_handler; |
4dc0da86 AK |
8941 | context = parent_event->overflow_handler_context; |
8942 | } | |
66832eb4 | 8943 | |
1879445d WN |
8944 | if (overflow_handler) { |
8945 | event->overflow_handler = overflow_handler; | |
8946 | event->overflow_handler_context = context; | |
9ecda41a WN |
8947 | } else if (is_write_backward(event)){ |
8948 | event->overflow_handler = perf_event_output_backward; | |
8949 | event->overflow_handler_context = NULL; | |
1879445d | 8950 | } else { |
9ecda41a | 8951 | event->overflow_handler = perf_event_output_forward; |
1879445d WN |
8952 | event->overflow_handler_context = NULL; |
8953 | } | |
97eaf530 | 8954 | |
0231bb53 | 8955 | perf_event__state_init(event); |
a86ed508 | 8956 | |
4aeb0b42 | 8957 | pmu = NULL; |
b8e83514 | 8958 | |
cdd6c482 | 8959 | hwc = &event->hw; |
bd2b5b12 | 8960 | hwc->sample_period = attr->sample_period; |
0d48696f | 8961 | if (attr->freq && attr->sample_freq) |
bd2b5b12 | 8962 | hwc->sample_period = 1; |
eced1dfc | 8963 | hwc->last_period = hwc->sample_period; |
bd2b5b12 | 8964 | |
e7850595 | 8965 | local64_set(&hwc->period_left, hwc->sample_period); |
60db5e09 | 8966 | |
2023b359 | 8967 | /* |
cdd6c482 | 8968 | * we currently do not support PERF_FORMAT_GROUP on inherited events |
2023b359 | 8969 | */ |
3dab77fb | 8970 | if (attr->inherit && (attr->read_format & PERF_FORMAT_GROUP)) |
90983b16 | 8971 | goto err_ns; |
a46a2300 YZ |
8972 | |
8973 | if (!has_branch_stack(event)) | |
8974 | event->attr.branch_sample_type = 0; | |
2023b359 | 8975 | |
79dff51e MF |
8976 | if (cgroup_fd != -1) { |
8977 | err = perf_cgroup_connect(cgroup_fd, event, attr, group_leader); | |
8978 | if (err) | |
8979 | goto err_ns; | |
8980 | } | |
8981 | ||
b0a873eb | 8982 | pmu = perf_init_event(event); |
4aeb0b42 | 8983 | if (!pmu) |
90983b16 FW |
8984 | goto err_ns; |
8985 | else if (IS_ERR(pmu)) { | |
4aeb0b42 | 8986 | err = PTR_ERR(pmu); |
90983b16 | 8987 | goto err_ns; |
621a01ea | 8988 | } |
d5d2bc0d | 8989 | |
bed5b25a AS |
8990 | err = exclusive_event_init(event); |
8991 | if (err) | |
8992 | goto err_pmu; | |
8993 | ||
375637bc AS |
8994 | if (has_addr_filter(event)) { |
8995 | event->addr_filters_offs = kcalloc(pmu->nr_addr_filters, | |
8996 | sizeof(unsigned long), | |
8997 | GFP_KERNEL); | |
8998 | if (!event->addr_filters_offs) | |
8999 | goto err_per_task; | |
9000 | ||
9001 | /* force hw sync on the address filters */ | |
9002 | event->addr_filters_gen = 1; | |
9003 | } | |
9004 | ||
cdd6c482 | 9005 | if (!event->parent) { |
927c7a9e | 9006 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) { |
97c79a38 | 9007 | err = get_callchain_buffers(attr->sample_max_stack); |
90983b16 | 9008 | if (err) |
375637bc | 9009 | goto err_addr_filters; |
d010b332 | 9010 | } |
f344011c | 9011 | } |
9ee318a7 | 9012 | |
927a5570 AS |
9013 | /* symmetric to unaccount_event() in _free_event() */ |
9014 | account_event(event); | |
9015 | ||
cdd6c482 | 9016 | return event; |
90983b16 | 9017 | |
375637bc AS |
9018 | err_addr_filters: |
9019 | kfree(event->addr_filters_offs); | |
9020 | ||
bed5b25a AS |
9021 | err_per_task: |
9022 | exclusive_event_destroy(event); | |
9023 | ||
90983b16 FW |
9024 | err_pmu: |
9025 | if (event->destroy) | |
9026 | event->destroy(event); | |
c464c76e | 9027 | module_put(pmu->module); |
90983b16 | 9028 | err_ns: |
79dff51e MF |
9029 | if (is_cgroup_event(event)) |
9030 | perf_detach_cgroup(event); | |
90983b16 FW |
9031 | if (event->ns) |
9032 | put_pid_ns(event->ns); | |
9033 | kfree(event); | |
9034 | ||
9035 | return ERR_PTR(err); | |
0793a61d TG |
9036 | } |
9037 | ||
cdd6c482 IM |
9038 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
9039 | struct perf_event_attr *attr) | |
974802ea | 9040 | { |
974802ea | 9041 | u32 size; |
cdf8073d | 9042 | int ret; |
974802ea PZ |
9043 | |
9044 | if (!access_ok(VERIFY_WRITE, uattr, PERF_ATTR_SIZE_VER0)) | |
9045 | return -EFAULT; | |
9046 | ||
9047 | /* | |
9048 | * zero the full structure, so that a short copy will be nice. | |
9049 | */ | |
9050 | memset(attr, 0, sizeof(*attr)); | |
9051 | ||
9052 | ret = get_user(size, &uattr->size); | |
9053 | if (ret) | |
9054 | return ret; | |
9055 | ||
9056 | if (size > PAGE_SIZE) /* silly large */ | |
9057 | goto err_size; | |
9058 | ||
9059 | if (!size) /* abi compat */ | |
9060 | size = PERF_ATTR_SIZE_VER0; | |
9061 | ||
9062 | if (size < PERF_ATTR_SIZE_VER0) | |
9063 | goto err_size; | |
9064 | ||
9065 | /* | |
9066 | * If we're handed a bigger struct than we know of, | |
cdf8073d IS |
9067 | * ensure all the unknown bits are 0 - i.e. new |
9068 | * user-space does not rely on any kernel feature | |
9069 | * extensions we dont know about yet. | |
974802ea PZ |
9070 | */ |
9071 | if (size > sizeof(*attr)) { | |
cdf8073d IS |
9072 | unsigned char __user *addr; |
9073 | unsigned char __user *end; | |
9074 | unsigned char val; | |
974802ea | 9075 | |
cdf8073d IS |
9076 | addr = (void __user *)uattr + sizeof(*attr); |
9077 | end = (void __user *)uattr + size; | |
974802ea | 9078 | |
cdf8073d | 9079 | for (; addr < end; addr++) { |
974802ea PZ |
9080 | ret = get_user(val, addr); |
9081 | if (ret) | |
9082 | return ret; | |
9083 | if (val) | |
9084 | goto err_size; | |
9085 | } | |
b3e62e35 | 9086 | size = sizeof(*attr); |
974802ea PZ |
9087 | } |
9088 | ||
9089 | ret = copy_from_user(attr, uattr, size); | |
9090 | if (ret) | |
9091 | return -EFAULT; | |
9092 | ||
cd757645 | 9093 | if (attr->__reserved_1) |
974802ea PZ |
9094 | return -EINVAL; |
9095 | ||
9096 | if (attr->sample_type & ~(PERF_SAMPLE_MAX-1)) | |
9097 | return -EINVAL; | |
9098 | ||
9099 | if (attr->read_format & ~(PERF_FORMAT_MAX-1)) | |
9100 | return -EINVAL; | |
9101 | ||
bce38cd5 SE |
9102 | if (attr->sample_type & PERF_SAMPLE_BRANCH_STACK) { |
9103 | u64 mask = attr->branch_sample_type; | |
9104 | ||
9105 | /* only using defined bits */ | |
9106 | if (mask & ~(PERF_SAMPLE_BRANCH_MAX-1)) | |
9107 | return -EINVAL; | |
9108 | ||
9109 | /* at least one branch bit must be set */ | |
9110 | if (!(mask & ~PERF_SAMPLE_BRANCH_PLM_ALL)) | |
9111 | return -EINVAL; | |
9112 | ||
bce38cd5 SE |
9113 | /* propagate priv level, when not set for branch */ |
9114 | if (!(mask & PERF_SAMPLE_BRANCH_PLM_ALL)) { | |
9115 | ||
9116 | /* exclude_kernel checked on syscall entry */ | |
9117 | if (!attr->exclude_kernel) | |
9118 | mask |= PERF_SAMPLE_BRANCH_KERNEL; | |
9119 | ||
9120 | if (!attr->exclude_user) | |
9121 | mask |= PERF_SAMPLE_BRANCH_USER; | |
9122 | ||
9123 | if (!attr->exclude_hv) | |
9124 | mask |= PERF_SAMPLE_BRANCH_HV; | |
9125 | /* | |
9126 | * adjust user setting (for HW filter setup) | |
9127 | */ | |
9128 | attr->branch_sample_type = mask; | |
9129 | } | |
e712209a SE |
9130 | /* privileged levels capture (kernel, hv): check permissions */ |
9131 | if ((mask & PERF_SAMPLE_BRANCH_PERM_PLM) | |
2b923c8f SE |
9132 | && perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) |
9133 | return -EACCES; | |
bce38cd5 | 9134 | } |
4018994f | 9135 | |
c5ebcedb | 9136 | if (attr->sample_type & PERF_SAMPLE_REGS_USER) { |
4018994f | 9137 | ret = perf_reg_validate(attr->sample_regs_user); |
c5ebcedb JO |
9138 | if (ret) |
9139 | return ret; | |
9140 | } | |
9141 | ||
9142 | if (attr->sample_type & PERF_SAMPLE_STACK_USER) { | |
9143 | if (!arch_perf_have_user_stack_dump()) | |
9144 | return -ENOSYS; | |
9145 | ||
9146 | /* | |
9147 | * We have __u32 type for the size, but so far | |
9148 | * we can only use __u16 as maximum due to the | |
9149 | * __u16 sample size limit. | |
9150 | */ | |
9151 | if (attr->sample_stack_user >= USHRT_MAX) | |
9152 | ret = -EINVAL; | |
9153 | else if (!IS_ALIGNED(attr->sample_stack_user, sizeof(u64))) | |
9154 | ret = -EINVAL; | |
9155 | } | |
4018994f | 9156 | |
60e2364e SE |
9157 | if (attr->sample_type & PERF_SAMPLE_REGS_INTR) |
9158 | ret = perf_reg_validate(attr->sample_regs_intr); | |
974802ea PZ |
9159 | out: |
9160 | return ret; | |
9161 | ||
9162 | err_size: | |
9163 | put_user(sizeof(*attr), &uattr->size); | |
9164 | ret = -E2BIG; | |
9165 | goto out; | |
9166 | } | |
9167 | ||
ac9721f3 PZ |
9168 | static int |
9169 | perf_event_set_output(struct perf_event *event, struct perf_event *output_event) | |
a4be7c27 | 9170 | { |
b69cf536 | 9171 | struct ring_buffer *rb = NULL; |
a4be7c27 PZ |
9172 | int ret = -EINVAL; |
9173 | ||
ac9721f3 | 9174 | if (!output_event) |
a4be7c27 PZ |
9175 | goto set; |
9176 | ||
ac9721f3 PZ |
9177 | /* don't allow circular references */ |
9178 | if (event == output_event) | |
a4be7c27 PZ |
9179 | goto out; |
9180 | ||
0f139300 PZ |
9181 | /* |
9182 | * Don't allow cross-cpu buffers | |
9183 | */ | |
9184 | if (output_event->cpu != event->cpu) | |
9185 | goto out; | |
9186 | ||
9187 | /* | |
76369139 | 9188 | * If its not a per-cpu rb, it must be the same task. |
0f139300 PZ |
9189 | */ |
9190 | if (output_event->cpu == -1 && output_event->ctx != event->ctx) | |
9191 | goto out; | |
9192 | ||
34f43927 PZ |
9193 | /* |
9194 | * Mixing clocks in the same buffer is trouble you don't need. | |
9195 | */ | |
9196 | if (output_event->clock != event->clock) | |
9197 | goto out; | |
9198 | ||
9ecda41a WN |
9199 | /* |
9200 | * Either writing ring buffer from beginning or from end. | |
9201 | * Mixing is not allowed. | |
9202 | */ | |
9203 | if (is_write_backward(output_event) != is_write_backward(event)) | |
9204 | goto out; | |
9205 | ||
45bfb2e5 PZ |
9206 | /* |
9207 | * If both events generate aux data, they must be on the same PMU | |
9208 | */ | |
9209 | if (has_aux(event) && has_aux(output_event) && | |
9210 | event->pmu != output_event->pmu) | |
9211 | goto out; | |
9212 | ||
a4be7c27 | 9213 | set: |
cdd6c482 | 9214 | mutex_lock(&event->mmap_mutex); |
ac9721f3 PZ |
9215 | /* Can't redirect output if we've got an active mmap() */ |
9216 | if (atomic_read(&event->mmap_count)) | |
9217 | goto unlock; | |
a4be7c27 | 9218 | |
ac9721f3 | 9219 | if (output_event) { |
76369139 FW |
9220 | /* get the rb we want to redirect to */ |
9221 | rb = ring_buffer_get(output_event); | |
9222 | if (!rb) | |
ac9721f3 | 9223 | goto unlock; |
a4be7c27 PZ |
9224 | } |
9225 | ||
b69cf536 | 9226 | ring_buffer_attach(event, rb); |
9bb5d40c | 9227 | |
a4be7c27 | 9228 | ret = 0; |
ac9721f3 PZ |
9229 | unlock: |
9230 | mutex_unlock(&event->mmap_mutex); | |
9231 | ||
a4be7c27 | 9232 | out: |
a4be7c27 PZ |
9233 | return ret; |
9234 | } | |
9235 | ||
f63a8daa PZ |
9236 | static void mutex_lock_double(struct mutex *a, struct mutex *b) |
9237 | { | |
9238 | if (b < a) | |
9239 | swap(a, b); | |
9240 | ||
9241 | mutex_lock(a); | |
9242 | mutex_lock_nested(b, SINGLE_DEPTH_NESTING); | |
9243 | } | |
9244 | ||
34f43927 PZ |
9245 | static int perf_event_set_clock(struct perf_event *event, clockid_t clk_id) |
9246 | { | |
9247 | bool nmi_safe = false; | |
9248 | ||
9249 | switch (clk_id) { | |
9250 | case CLOCK_MONOTONIC: | |
9251 | event->clock = &ktime_get_mono_fast_ns; | |
9252 | nmi_safe = true; | |
9253 | break; | |
9254 | ||
9255 | case CLOCK_MONOTONIC_RAW: | |
9256 | event->clock = &ktime_get_raw_fast_ns; | |
9257 | nmi_safe = true; | |
9258 | break; | |
9259 | ||
9260 | case CLOCK_REALTIME: | |
9261 | event->clock = &ktime_get_real_ns; | |
9262 | break; | |
9263 | ||
9264 | case CLOCK_BOOTTIME: | |
9265 | event->clock = &ktime_get_boot_ns; | |
9266 | break; | |
9267 | ||
9268 | case CLOCK_TAI: | |
9269 | event->clock = &ktime_get_tai_ns; | |
9270 | break; | |
9271 | ||
9272 | default: | |
9273 | return -EINVAL; | |
9274 | } | |
9275 | ||
9276 | if (!nmi_safe && !(event->pmu->capabilities & PERF_PMU_CAP_NO_NMI)) | |
9277 | return -EINVAL; | |
9278 | ||
9279 | return 0; | |
9280 | } | |
9281 | ||
0793a61d | 9282 | /** |
cdd6c482 | 9283 | * sys_perf_event_open - open a performance event, associate it to a task/cpu |
9f66a381 | 9284 | * |
cdd6c482 | 9285 | * @attr_uptr: event_id type attributes for monitoring/sampling |
0793a61d | 9286 | * @pid: target pid |
9f66a381 | 9287 | * @cpu: target cpu |
cdd6c482 | 9288 | * @group_fd: group leader event fd |
0793a61d | 9289 | */ |
cdd6c482 IM |
9290 | SYSCALL_DEFINE5(perf_event_open, |
9291 | struct perf_event_attr __user *, attr_uptr, | |
2743a5b0 | 9292 | pid_t, pid, int, cpu, int, group_fd, unsigned long, flags) |
0793a61d | 9293 | { |
b04243ef PZ |
9294 | struct perf_event *group_leader = NULL, *output_event = NULL; |
9295 | struct perf_event *event, *sibling; | |
cdd6c482 | 9296 | struct perf_event_attr attr; |
f63a8daa | 9297 | struct perf_event_context *ctx, *uninitialized_var(gctx); |
cdd6c482 | 9298 | struct file *event_file = NULL; |
2903ff01 | 9299 | struct fd group = {NULL, 0}; |
38a81da2 | 9300 | struct task_struct *task = NULL; |
89a1e187 | 9301 | struct pmu *pmu; |
ea635c64 | 9302 | int event_fd; |
b04243ef | 9303 | int move_group = 0; |
dc86cabe | 9304 | int err; |
a21b0b35 | 9305 | int f_flags = O_RDWR; |
79dff51e | 9306 | int cgroup_fd = -1; |
0793a61d | 9307 | |
2743a5b0 | 9308 | /* for future expandability... */ |
e5d1367f | 9309 | if (flags & ~PERF_FLAG_ALL) |
2743a5b0 PM |
9310 | return -EINVAL; |
9311 | ||
dc86cabe IM |
9312 | err = perf_copy_attr(attr_uptr, &attr); |
9313 | if (err) | |
9314 | return err; | |
eab656ae | 9315 | |
0764771d PZ |
9316 | if (!attr.exclude_kernel) { |
9317 | if (perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) | |
9318 | return -EACCES; | |
9319 | } | |
9320 | ||
df58ab24 | 9321 | if (attr.freq) { |
cdd6c482 | 9322 | if (attr.sample_freq > sysctl_perf_event_sample_rate) |
df58ab24 | 9323 | return -EINVAL; |
0819b2e3 PZ |
9324 | } else { |
9325 | if (attr.sample_period & (1ULL << 63)) | |
9326 | return -EINVAL; | |
df58ab24 PZ |
9327 | } |
9328 | ||
97c79a38 ACM |
9329 | if (!attr.sample_max_stack) |
9330 | attr.sample_max_stack = sysctl_perf_event_max_stack; | |
9331 | ||
e5d1367f SE |
9332 | /* |
9333 | * In cgroup mode, the pid argument is used to pass the fd | |
9334 | * opened to the cgroup directory in cgroupfs. The cpu argument | |
9335 | * designates the cpu on which to monitor threads from that | |
9336 | * cgroup. | |
9337 | */ | |
9338 | if ((flags & PERF_FLAG_PID_CGROUP) && (pid == -1 || cpu == -1)) | |
9339 | return -EINVAL; | |
9340 | ||
a21b0b35 YD |
9341 | if (flags & PERF_FLAG_FD_CLOEXEC) |
9342 | f_flags |= O_CLOEXEC; | |
9343 | ||
9344 | event_fd = get_unused_fd_flags(f_flags); | |
ea635c64 AV |
9345 | if (event_fd < 0) |
9346 | return event_fd; | |
9347 | ||
ac9721f3 | 9348 | if (group_fd != -1) { |
2903ff01 AV |
9349 | err = perf_fget_light(group_fd, &group); |
9350 | if (err) | |
d14b12d7 | 9351 | goto err_fd; |
2903ff01 | 9352 | group_leader = group.file->private_data; |
ac9721f3 PZ |
9353 | if (flags & PERF_FLAG_FD_OUTPUT) |
9354 | output_event = group_leader; | |
9355 | if (flags & PERF_FLAG_FD_NO_GROUP) | |
9356 | group_leader = NULL; | |
9357 | } | |
9358 | ||
e5d1367f | 9359 | if (pid != -1 && !(flags & PERF_FLAG_PID_CGROUP)) { |
c6be5a5c PZ |
9360 | task = find_lively_task_by_vpid(pid); |
9361 | if (IS_ERR(task)) { | |
9362 | err = PTR_ERR(task); | |
9363 | goto err_group_fd; | |
9364 | } | |
9365 | } | |
9366 | ||
1f4ee503 PZ |
9367 | if (task && group_leader && |
9368 | group_leader->attr.inherit != attr.inherit) { | |
9369 | err = -EINVAL; | |
9370 | goto err_task; | |
9371 | } | |
9372 | ||
fbfc623f YZ |
9373 | get_online_cpus(); |
9374 | ||
79c9ce57 PZ |
9375 | if (task) { |
9376 | err = mutex_lock_interruptible(&task->signal->cred_guard_mutex); | |
9377 | if (err) | |
9378 | goto err_cpus; | |
9379 | ||
9380 | /* | |
9381 | * Reuse ptrace permission checks for now. | |
9382 | * | |
9383 | * We must hold cred_guard_mutex across this and any potential | |
9384 | * perf_install_in_context() call for this new event to | |
9385 | * serialize against exec() altering our credentials (and the | |
9386 | * perf_event_exit_task() that could imply). | |
9387 | */ | |
9388 | err = -EACCES; | |
9389 | if (!ptrace_may_access(task, PTRACE_MODE_READ_REALCREDS)) | |
9390 | goto err_cred; | |
9391 | } | |
9392 | ||
79dff51e MF |
9393 | if (flags & PERF_FLAG_PID_CGROUP) |
9394 | cgroup_fd = pid; | |
9395 | ||
4dc0da86 | 9396 | event = perf_event_alloc(&attr, cpu, task, group_leader, NULL, |
79dff51e | 9397 | NULL, NULL, cgroup_fd); |
d14b12d7 SE |
9398 | if (IS_ERR(event)) { |
9399 | err = PTR_ERR(event); | |
79c9ce57 | 9400 | goto err_cred; |
d14b12d7 SE |
9401 | } |
9402 | ||
53b25335 VW |
9403 | if (is_sampling_event(event)) { |
9404 | if (event->pmu->capabilities & PERF_PMU_CAP_NO_INTERRUPT) { | |
a1396555 | 9405 | err = -EOPNOTSUPP; |
53b25335 VW |
9406 | goto err_alloc; |
9407 | } | |
9408 | } | |
9409 | ||
89a1e187 PZ |
9410 | /* |
9411 | * Special case software events and allow them to be part of | |
9412 | * any hardware group. | |
9413 | */ | |
9414 | pmu = event->pmu; | |
b04243ef | 9415 | |
34f43927 PZ |
9416 | if (attr.use_clockid) { |
9417 | err = perf_event_set_clock(event, attr.clockid); | |
9418 | if (err) | |
9419 | goto err_alloc; | |
9420 | } | |
9421 | ||
b04243ef PZ |
9422 | if (group_leader && |
9423 | (is_software_event(event) != is_software_event(group_leader))) { | |
9424 | if (is_software_event(event)) { | |
9425 | /* | |
9426 | * If event and group_leader are not both a software | |
9427 | * event, and event is, then group leader is not. | |
9428 | * | |
9429 | * Allow the addition of software events to !software | |
9430 | * groups, this is safe because software events never | |
9431 | * fail to schedule. | |
9432 | */ | |
9433 | pmu = group_leader->pmu; | |
9434 | } else if (is_software_event(group_leader) && | |
9435 | (group_leader->group_flags & PERF_GROUP_SOFTWARE)) { | |
9436 | /* | |
9437 | * In case the group is a pure software group, and we | |
9438 | * try to add a hardware event, move the whole group to | |
9439 | * the hardware context. | |
9440 | */ | |
9441 | move_group = 1; | |
9442 | } | |
9443 | } | |
89a1e187 PZ |
9444 | |
9445 | /* | |
9446 | * Get the target context (task or percpu): | |
9447 | */ | |
4af57ef2 | 9448 | ctx = find_get_context(pmu, task, event); |
89a1e187 PZ |
9449 | if (IS_ERR(ctx)) { |
9450 | err = PTR_ERR(ctx); | |
c6be5a5c | 9451 | goto err_alloc; |
89a1e187 PZ |
9452 | } |
9453 | ||
bed5b25a AS |
9454 | if ((pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE) && group_leader) { |
9455 | err = -EBUSY; | |
9456 | goto err_context; | |
9457 | } | |
9458 | ||
ccff286d | 9459 | /* |
cdd6c482 | 9460 | * Look up the group leader (we will attach this event to it): |
04289bb9 | 9461 | */ |
ac9721f3 | 9462 | if (group_leader) { |
dc86cabe | 9463 | err = -EINVAL; |
04289bb9 | 9464 | |
04289bb9 | 9465 | /* |
ccff286d IM |
9466 | * Do not allow a recursive hierarchy (this new sibling |
9467 | * becoming part of another group-sibling): | |
9468 | */ | |
9469 | if (group_leader->group_leader != group_leader) | |
c3f00c70 | 9470 | goto err_context; |
34f43927 PZ |
9471 | |
9472 | /* All events in a group should have the same clock */ | |
9473 | if (group_leader->clock != event->clock) | |
9474 | goto err_context; | |
9475 | ||
ccff286d IM |
9476 | /* |
9477 | * Do not allow to attach to a group in a different | |
9478 | * task or CPU context: | |
04289bb9 | 9479 | */ |
b04243ef | 9480 | if (move_group) { |
c3c87e77 PZ |
9481 | /* |
9482 | * Make sure we're both on the same task, or both | |
9483 | * per-cpu events. | |
9484 | */ | |
9485 | if (group_leader->ctx->task != ctx->task) | |
9486 | goto err_context; | |
9487 | ||
9488 | /* | |
9489 | * Make sure we're both events for the same CPU; | |
9490 | * grouping events for different CPUs is broken; since | |
9491 | * you can never concurrently schedule them anyhow. | |
9492 | */ | |
9493 | if (group_leader->cpu != event->cpu) | |
b04243ef PZ |
9494 | goto err_context; |
9495 | } else { | |
9496 | if (group_leader->ctx != ctx) | |
9497 | goto err_context; | |
9498 | } | |
9499 | ||
3b6f9e5c PM |
9500 | /* |
9501 | * Only a group leader can be exclusive or pinned | |
9502 | */ | |
0d48696f | 9503 | if (attr.exclusive || attr.pinned) |
c3f00c70 | 9504 | goto err_context; |
ac9721f3 PZ |
9505 | } |
9506 | ||
9507 | if (output_event) { | |
9508 | err = perf_event_set_output(event, output_event); | |
9509 | if (err) | |
c3f00c70 | 9510 | goto err_context; |
ac9721f3 | 9511 | } |
0793a61d | 9512 | |
a21b0b35 YD |
9513 | event_file = anon_inode_getfile("[perf_event]", &perf_fops, event, |
9514 | f_flags); | |
ea635c64 AV |
9515 | if (IS_ERR(event_file)) { |
9516 | err = PTR_ERR(event_file); | |
201c2f85 | 9517 | event_file = NULL; |
c3f00c70 | 9518 | goto err_context; |
ea635c64 | 9519 | } |
9b51f66d | 9520 | |
b04243ef | 9521 | if (move_group) { |
f63a8daa | 9522 | gctx = group_leader->ctx; |
f55fc2a5 | 9523 | mutex_lock_double(&gctx->mutex, &ctx->mutex); |
84c4e620 PZ |
9524 | if (gctx->task == TASK_TOMBSTONE) { |
9525 | err = -ESRCH; | |
9526 | goto err_locked; | |
9527 | } | |
f55fc2a5 PZ |
9528 | } else { |
9529 | mutex_lock(&ctx->mutex); | |
9530 | } | |
9531 | ||
84c4e620 PZ |
9532 | if (ctx->task == TASK_TOMBSTONE) { |
9533 | err = -ESRCH; | |
9534 | goto err_locked; | |
9535 | } | |
9536 | ||
a723968c PZ |
9537 | if (!perf_event_validate_size(event)) { |
9538 | err = -E2BIG; | |
9539 | goto err_locked; | |
9540 | } | |
9541 | ||
f55fc2a5 PZ |
9542 | /* |
9543 | * Must be under the same ctx::mutex as perf_install_in_context(), | |
9544 | * because we need to serialize with concurrent event creation. | |
9545 | */ | |
9546 | if (!exclusive_event_installable(event, ctx)) { | |
9547 | /* exclusive and group stuff are assumed mutually exclusive */ | |
9548 | WARN_ON_ONCE(move_group); | |
f63a8daa | 9549 | |
f55fc2a5 PZ |
9550 | err = -EBUSY; |
9551 | goto err_locked; | |
9552 | } | |
f63a8daa | 9553 | |
f55fc2a5 PZ |
9554 | WARN_ON_ONCE(ctx->parent_ctx); |
9555 | ||
79c9ce57 PZ |
9556 | /* |
9557 | * This is the point on no return; we cannot fail hereafter. This is | |
9558 | * where we start modifying current state. | |
9559 | */ | |
9560 | ||
f55fc2a5 | 9561 | if (move_group) { |
f63a8daa PZ |
9562 | /* |
9563 | * See perf_event_ctx_lock() for comments on the details | |
9564 | * of swizzling perf_event::ctx. | |
9565 | */ | |
45a0e07a | 9566 | perf_remove_from_context(group_leader, 0); |
0231bb53 | 9567 | |
b04243ef PZ |
9568 | list_for_each_entry(sibling, &group_leader->sibling_list, |
9569 | group_entry) { | |
45a0e07a | 9570 | perf_remove_from_context(sibling, 0); |
b04243ef PZ |
9571 | put_ctx(gctx); |
9572 | } | |
b04243ef | 9573 | |
f63a8daa PZ |
9574 | /* |
9575 | * Wait for everybody to stop referencing the events through | |
9576 | * the old lists, before installing it on new lists. | |
9577 | */ | |
0cda4c02 | 9578 | synchronize_rcu(); |
f63a8daa | 9579 | |
8f95b435 PZI |
9580 | /* |
9581 | * Install the group siblings before the group leader. | |
9582 | * | |
9583 | * Because a group leader will try and install the entire group | |
9584 | * (through the sibling list, which is still in-tact), we can | |
9585 | * end up with siblings installed in the wrong context. | |
9586 | * | |
9587 | * By installing siblings first we NO-OP because they're not | |
9588 | * reachable through the group lists. | |
9589 | */ | |
b04243ef PZ |
9590 | list_for_each_entry(sibling, &group_leader->sibling_list, |
9591 | group_entry) { | |
8f95b435 | 9592 | perf_event__state_init(sibling); |
9fc81d87 | 9593 | perf_install_in_context(ctx, sibling, sibling->cpu); |
b04243ef PZ |
9594 | get_ctx(ctx); |
9595 | } | |
8f95b435 PZI |
9596 | |
9597 | /* | |
9598 | * Removing from the context ends up with disabled | |
9599 | * event. What we want here is event in the initial | |
9600 | * startup state, ready to be add into new context. | |
9601 | */ | |
9602 | perf_event__state_init(group_leader); | |
9603 | perf_install_in_context(ctx, group_leader, group_leader->cpu); | |
9604 | get_ctx(ctx); | |
b04243ef | 9605 | |
f55fc2a5 PZ |
9606 | /* |
9607 | * Now that all events are installed in @ctx, nothing | |
9608 | * references @gctx anymore, so drop the last reference we have | |
9609 | * on it. | |
9610 | */ | |
9611 | put_ctx(gctx); | |
bed5b25a AS |
9612 | } |
9613 | ||
f73e22ab PZ |
9614 | /* |
9615 | * Precalculate sample_data sizes; do while holding ctx::mutex such | |
9616 | * that we're serialized against further additions and before | |
9617 | * perf_install_in_context() which is the point the event is active and | |
9618 | * can use these values. | |
9619 | */ | |
9620 | perf_event__header_size(event); | |
9621 | perf_event__id_header_size(event); | |
9622 | ||
78cd2c74 PZ |
9623 | event->owner = current; |
9624 | ||
e2d37cd2 | 9625 | perf_install_in_context(ctx, event, event->cpu); |
fe4b04fa | 9626 | perf_unpin_context(ctx); |
f63a8daa | 9627 | |
f55fc2a5 | 9628 | if (move_group) |
f63a8daa | 9629 | mutex_unlock(&gctx->mutex); |
d859e29f | 9630 | mutex_unlock(&ctx->mutex); |
9b51f66d | 9631 | |
79c9ce57 PZ |
9632 | if (task) { |
9633 | mutex_unlock(&task->signal->cred_guard_mutex); | |
9634 | put_task_struct(task); | |
9635 | } | |
9636 | ||
fbfc623f YZ |
9637 | put_online_cpus(); |
9638 | ||
cdd6c482 IM |
9639 | mutex_lock(¤t->perf_event_mutex); |
9640 | list_add_tail(&event->owner_entry, ¤t->perf_event_list); | |
9641 | mutex_unlock(¤t->perf_event_mutex); | |
082ff5a2 | 9642 | |
8a49542c PZ |
9643 | /* |
9644 | * Drop the reference on the group_event after placing the | |
9645 | * new event on the sibling_list. This ensures destruction | |
9646 | * of the group leader will find the pointer to itself in | |
9647 | * perf_group_detach(). | |
9648 | */ | |
2903ff01 | 9649 | fdput(group); |
ea635c64 AV |
9650 | fd_install(event_fd, event_file); |
9651 | return event_fd; | |
0793a61d | 9652 | |
f55fc2a5 PZ |
9653 | err_locked: |
9654 | if (move_group) | |
9655 | mutex_unlock(&gctx->mutex); | |
9656 | mutex_unlock(&ctx->mutex); | |
9657 | /* err_file: */ | |
9658 | fput(event_file); | |
c3f00c70 | 9659 | err_context: |
fe4b04fa | 9660 | perf_unpin_context(ctx); |
ea635c64 | 9661 | put_ctx(ctx); |
c6be5a5c | 9662 | err_alloc: |
13005627 PZ |
9663 | /* |
9664 | * If event_file is set, the fput() above will have called ->release() | |
9665 | * and that will take care of freeing the event. | |
9666 | */ | |
9667 | if (!event_file) | |
9668 | free_event(event); | |
79c9ce57 PZ |
9669 | err_cred: |
9670 | if (task) | |
9671 | mutex_unlock(&task->signal->cred_guard_mutex); | |
1f4ee503 | 9672 | err_cpus: |
fbfc623f | 9673 | put_online_cpus(); |
1f4ee503 | 9674 | err_task: |
e7d0bc04 PZ |
9675 | if (task) |
9676 | put_task_struct(task); | |
89a1e187 | 9677 | err_group_fd: |
2903ff01 | 9678 | fdput(group); |
ea635c64 AV |
9679 | err_fd: |
9680 | put_unused_fd(event_fd); | |
dc86cabe | 9681 | return err; |
0793a61d TG |
9682 | } |
9683 | ||
fb0459d7 AV |
9684 | /** |
9685 | * perf_event_create_kernel_counter | |
9686 | * | |
9687 | * @attr: attributes of the counter to create | |
9688 | * @cpu: cpu in which the counter is bound | |
38a81da2 | 9689 | * @task: task to profile (NULL for percpu) |
fb0459d7 AV |
9690 | */ |
9691 | struct perf_event * | |
9692 | perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, | |
38a81da2 | 9693 | struct task_struct *task, |
4dc0da86 AK |
9694 | perf_overflow_handler_t overflow_handler, |
9695 | void *context) | |
fb0459d7 | 9696 | { |
fb0459d7 | 9697 | struct perf_event_context *ctx; |
c3f00c70 | 9698 | struct perf_event *event; |
fb0459d7 | 9699 | int err; |
d859e29f | 9700 | |
fb0459d7 AV |
9701 | /* |
9702 | * Get the target context (task or percpu): | |
9703 | */ | |
d859e29f | 9704 | |
4dc0da86 | 9705 | event = perf_event_alloc(attr, cpu, task, NULL, NULL, |
79dff51e | 9706 | overflow_handler, context, -1); |
c3f00c70 PZ |
9707 | if (IS_ERR(event)) { |
9708 | err = PTR_ERR(event); | |
9709 | goto err; | |
9710 | } | |
d859e29f | 9711 | |
f8697762 | 9712 | /* Mark owner so we could distinguish it from user events. */ |
63b6da39 | 9713 | event->owner = TASK_TOMBSTONE; |
f8697762 | 9714 | |
4af57ef2 | 9715 | ctx = find_get_context(event->pmu, task, event); |
c6567f64 FW |
9716 | if (IS_ERR(ctx)) { |
9717 | err = PTR_ERR(ctx); | |
c3f00c70 | 9718 | goto err_free; |
d859e29f | 9719 | } |
fb0459d7 | 9720 | |
fb0459d7 AV |
9721 | WARN_ON_ONCE(ctx->parent_ctx); |
9722 | mutex_lock(&ctx->mutex); | |
84c4e620 PZ |
9723 | if (ctx->task == TASK_TOMBSTONE) { |
9724 | err = -ESRCH; | |
9725 | goto err_unlock; | |
9726 | } | |
9727 | ||
bed5b25a | 9728 | if (!exclusive_event_installable(event, ctx)) { |
bed5b25a | 9729 | err = -EBUSY; |
84c4e620 | 9730 | goto err_unlock; |
bed5b25a AS |
9731 | } |
9732 | ||
fb0459d7 | 9733 | perf_install_in_context(ctx, event, cpu); |
fe4b04fa | 9734 | perf_unpin_context(ctx); |
fb0459d7 AV |
9735 | mutex_unlock(&ctx->mutex); |
9736 | ||
fb0459d7 AV |
9737 | return event; |
9738 | ||
84c4e620 PZ |
9739 | err_unlock: |
9740 | mutex_unlock(&ctx->mutex); | |
9741 | perf_unpin_context(ctx); | |
9742 | put_ctx(ctx); | |
c3f00c70 PZ |
9743 | err_free: |
9744 | free_event(event); | |
9745 | err: | |
c6567f64 | 9746 | return ERR_PTR(err); |
9b51f66d | 9747 | } |
fb0459d7 | 9748 | EXPORT_SYMBOL_GPL(perf_event_create_kernel_counter); |
9b51f66d | 9749 | |
0cda4c02 YZ |
9750 | void perf_pmu_migrate_context(struct pmu *pmu, int src_cpu, int dst_cpu) |
9751 | { | |
9752 | struct perf_event_context *src_ctx; | |
9753 | struct perf_event_context *dst_ctx; | |
9754 | struct perf_event *event, *tmp; | |
9755 | LIST_HEAD(events); | |
9756 | ||
9757 | src_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, src_cpu)->ctx; | |
9758 | dst_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, dst_cpu)->ctx; | |
9759 | ||
f63a8daa PZ |
9760 | /* |
9761 | * See perf_event_ctx_lock() for comments on the details | |
9762 | * of swizzling perf_event::ctx. | |
9763 | */ | |
9764 | mutex_lock_double(&src_ctx->mutex, &dst_ctx->mutex); | |
0cda4c02 YZ |
9765 | list_for_each_entry_safe(event, tmp, &src_ctx->event_list, |
9766 | event_entry) { | |
45a0e07a | 9767 | perf_remove_from_context(event, 0); |
9a545de0 | 9768 | unaccount_event_cpu(event, src_cpu); |
0cda4c02 | 9769 | put_ctx(src_ctx); |
9886167d | 9770 | list_add(&event->migrate_entry, &events); |
0cda4c02 | 9771 | } |
0cda4c02 | 9772 | |
8f95b435 PZI |
9773 | /* |
9774 | * Wait for the events to quiesce before re-instating them. | |
9775 | */ | |
0cda4c02 YZ |
9776 | synchronize_rcu(); |
9777 | ||
8f95b435 PZI |
9778 | /* |
9779 | * Re-instate events in 2 passes. | |
9780 | * | |
9781 | * Skip over group leaders and only install siblings on this first | |
9782 | * pass, siblings will not get enabled without a leader, however a | |
9783 | * leader will enable its siblings, even if those are still on the old | |
9784 | * context. | |
9785 | */ | |
9786 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { | |
9787 | if (event->group_leader == event) | |
9788 | continue; | |
9789 | ||
9790 | list_del(&event->migrate_entry); | |
9791 | if (event->state >= PERF_EVENT_STATE_OFF) | |
9792 | event->state = PERF_EVENT_STATE_INACTIVE; | |
9793 | account_event_cpu(event, dst_cpu); | |
9794 | perf_install_in_context(dst_ctx, event, dst_cpu); | |
9795 | get_ctx(dst_ctx); | |
9796 | } | |
9797 | ||
9798 | /* | |
9799 | * Once all the siblings are setup properly, install the group leaders | |
9800 | * to make it go. | |
9801 | */ | |
9886167d PZ |
9802 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { |
9803 | list_del(&event->migrate_entry); | |
0cda4c02 YZ |
9804 | if (event->state >= PERF_EVENT_STATE_OFF) |
9805 | event->state = PERF_EVENT_STATE_INACTIVE; | |
9a545de0 | 9806 | account_event_cpu(event, dst_cpu); |
0cda4c02 YZ |
9807 | perf_install_in_context(dst_ctx, event, dst_cpu); |
9808 | get_ctx(dst_ctx); | |
9809 | } | |
9810 | mutex_unlock(&dst_ctx->mutex); | |
f63a8daa | 9811 | mutex_unlock(&src_ctx->mutex); |
0cda4c02 YZ |
9812 | } |
9813 | EXPORT_SYMBOL_GPL(perf_pmu_migrate_context); | |
9814 | ||
cdd6c482 | 9815 | static void sync_child_event(struct perf_event *child_event, |
38b200d6 | 9816 | struct task_struct *child) |
d859e29f | 9817 | { |
cdd6c482 | 9818 | struct perf_event *parent_event = child_event->parent; |
8bc20959 | 9819 | u64 child_val; |
d859e29f | 9820 | |
cdd6c482 IM |
9821 | if (child_event->attr.inherit_stat) |
9822 | perf_event_read_event(child_event, child); | |
38b200d6 | 9823 | |
b5e58793 | 9824 | child_val = perf_event_count(child_event); |
d859e29f PM |
9825 | |
9826 | /* | |
9827 | * Add back the child's count to the parent's count: | |
9828 | */ | |
a6e6dea6 | 9829 | atomic64_add(child_val, &parent_event->child_count); |
cdd6c482 IM |
9830 | atomic64_add(child_event->total_time_enabled, |
9831 | &parent_event->child_total_time_enabled); | |
9832 | atomic64_add(child_event->total_time_running, | |
9833 | &parent_event->child_total_time_running); | |
d859e29f PM |
9834 | } |
9835 | ||
9b51f66d | 9836 | static void |
8ba289b8 PZ |
9837 | perf_event_exit_event(struct perf_event *child_event, |
9838 | struct perf_event_context *child_ctx, | |
9839 | struct task_struct *child) | |
9b51f66d | 9840 | { |
8ba289b8 PZ |
9841 | struct perf_event *parent_event = child_event->parent; |
9842 | ||
1903d50c PZ |
9843 | /* |
9844 | * Do not destroy the 'original' grouping; because of the context | |
9845 | * switch optimization the original events could've ended up in a | |
9846 | * random child task. | |
9847 | * | |
9848 | * If we were to destroy the original group, all group related | |
9849 | * operations would cease to function properly after this random | |
9850 | * child dies. | |
9851 | * | |
9852 | * Do destroy all inherited groups, we don't care about those | |
9853 | * and being thorough is better. | |
9854 | */ | |
32132a3d PZ |
9855 | raw_spin_lock_irq(&child_ctx->lock); |
9856 | WARN_ON_ONCE(child_ctx->is_active); | |
9857 | ||
8ba289b8 | 9858 | if (parent_event) |
32132a3d PZ |
9859 | perf_group_detach(child_event); |
9860 | list_del_event(child_event, child_ctx); | |
a69b0ca4 | 9861 | child_event->state = PERF_EVENT_STATE_EXIT; /* is_event_hup() */ |
32132a3d | 9862 | raw_spin_unlock_irq(&child_ctx->lock); |
0cc0c027 | 9863 | |
9b51f66d | 9864 | /* |
8ba289b8 | 9865 | * Parent events are governed by their filedesc, retain them. |
9b51f66d | 9866 | */ |
8ba289b8 | 9867 | if (!parent_event) { |
179033b3 | 9868 | perf_event_wakeup(child_event); |
8ba289b8 | 9869 | return; |
4bcf349a | 9870 | } |
8ba289b8 PZ |
9871 | /* |
9872 | * Child events can be cleaned up. | |
9873 | */ | |
9874 | ||
9875 | sync_child_event(child_event, child); | |
9876 | ||
9877 | /* | |
9878 | * Remove this event from the parent's list | |
9879 | */ | |
9880 | WARN_ON_ONCE(parent_event->ctx->parent_ctx); | |
9881 | mutex_lock(&parent_event->child_mutex); | |
9882 | list_del_init(&child_event->child_list); | |
9883 | mutex_unlock(&parent_event->child_mutex); | |
9884 | ||
9885 | /* | |
9886 | * Kick perf_poll() for is_event_hup(). | |
9887 | */ | |
9888 | perf_event_wakeup(parent_event); | |
9889 | free_event(child_event); | |
9890 | put_event(parent_event); | |
9b51f66d IM |
9891 | } |
9892 | ||
8dc85d54 | 9893 | static void perf_event_exit_task_context(struct task_struct *child, int ctxn) |
9b51f66d | 9894 | { |
211de6eb | 9895 | struct perf_event_context *child_ctx, *clone_ctx = NULL; |
63b6da39 | 9896 | struct perf_event *child_event, *next; |
63b6da39 PZ |
9897 | |
9898 | WARN_ON_ONCE(child != current); | |
9b51f66d | 9899 | |
6a3351b6 | 9900 | child_ctx = perf_pin_task_context(child, ctxn); |
63b6da39 | 9901 | if (!child_ctx) |
9b51f66d IM |
9902 | return; |
9903 | ||
ad3a37de | 9904 | /* |
6a3351b6 PZ |
9905 | * In order to reduce the amount of tricky in ctx tear-down, we hold |
9906 | * ctx::mutex over the entire thing. This serializes against almost | |
9907 | * everything that wants to access the ctx. | |
9908 | * | |
9909 | * The exception is sys_perf_event_open() / | |
9910 | * perf_event_create_kernel_count() which does find_get_context() | |
9911 | * without ctx::mutex (it cannot because of the move_group double mutex | |
9912 | * lock thing). See the comments in perf_install_in_context(). | |
ad3a37de | 9913 | */ |
6a3351b6 | 9914 | mutex_lock(&child_ctx->mutex); |
c93f7669 PM |
9915 | |
9916 | /* | |
6a3351b6 PZ |
9917 | * In a single ctx::lock section, de-schedule the events and detach the |
9918 | * context from the task such that we cannot ever get it scheduled back | |
9919 | * in. | |
c93f7669 | 9920 | */ |
6a3351b6 | 9921 | raw_spin_lock_irq(&child_ctx->lock); |
63b6da39 | 9922 | task_ctx_sched_out(__get_cpu_context(child_ctx), child_ctx); |
4a1c0f26 | 9923 | |
71a851b4 | 9924 | /* |
63b6da39 PZ |
9925 | * Now that the context is inactive, destroy the task <-> ctx relation |
9926 | * and mark the context dead. | |
71a851b4 | 9927 | */ |
63b6da39 PZ |
9928 | RCU_INIT_POINTER(child->perf_event_ctxp[ctxn], NULL); |
9929 | put_ctx(child_ctx); /* cannot be last */ | |
9930 | WRITE_ONCE(child_ctx->task, TASK_TOMBSTONE); | |
9931 | put_task_struct(current); /* cannot be last */ | |
4a1c0f26 | 9932 | |
211de6eb | 9933 | clone_ctx = unclone_ctx(child_ctx); |
6a3351b6 | 9934 | raw_spin_unlock_irq(&child_ctx->lock); |
9f498cc5 | 9935 | |
211de6eb PZ |
9936 | if (clone_ctx) |
9937 | put_ctx(clone_ctx); | |
4a1c0f26 | 9938 | |
9f498cc5 | 9939 | /* |
cdd6c482 IM |
9940 | * Report the task dead after unscheduling the events so that we |
9941 | * won't get any samples after PERF_RECORD_EXIT. We can however still | |
9942 | * get a few PERF_RECORD_READ events. | |
9f498cc5 | 9943 | */ |
cdd6c482 | 9944 | perf_event_task(child, child_ctx, 0); |
a63eaf34 | 9945 | |
ebf905fc | 9946 | list_for_each_entry_safe(child_event, next, &child_ctx->event_list, event_entry) |
8ba289b8 | 9947 | perf_event_exit_event(child_event, child_ctx, child); |
8bc20959 | 9948 | |
a63eaf34 PM |
9949 | mutex_unlock(&child_ctx->mutex); |
9950 | ||
9951 | put_ctx(child_ctx); | |
9b51f66d IM |
9952 | } |
9953 | ||
8dc85d54 PZ |
9954 | /* |
9955 | * When a child task exits, feed back event values to parent events. | |
79c9ce57 PZ |
9956 | * |
9957 | * Can be called with cred_guard_mutex held when called from | |
9958 | * install_exec_creds(). | |
8dc85d54 PZ |
9959 | */ |
9960 | void perf_event_exit_task(struct task_struct *child) | |
9961 | { | |
8882135b | 9962 | struct perf_event *event, *tmp; |
8dc85d54 PZ |
9963 | int ctxn; |
9964 | ||
8882135b PZ |
9965 | mutex_lock(&child->perf_event_mutex); |
9966 | list_for_each_entry_safe(event, tmp, &child->perf_event_list, | |
9967 | owner_entry) { | |
9968 | list_del_init(&event->owner_entry); | |
9969 | ||
9970 | /* | |
9971 | * Ensure the list deletion is visible before we clear | |
9972 | * the owner, closes a race against perf_release() where | |
9973 | * we need to serialize on the owner->perf_event_mutex. | |
9974 | */ | |
f47c02c0 | 9975 | smp_store_release(&event->owner, NULL); |
8882135b PZ |
9976 | } |
9977 | mutex_unlock(&child->perf_event_mutex); | |
9978 | ||
8dc85d54 PZ |
9979 | for_each_task_context_nr(ctxn) |
9980 | perf_event_exit_task_context(child, ctxn); | |
4e93ad60 JO |
9981 | |
9982 | /* | |
9983 | * The perf_event_exit_task_context calls perf_event_task | |
9984 | * with child's task_ctx, which generates EXIT events for | |
9985 | * child contexts and sets child->perf_event_ctxp[] to NULL. | |
9986 | * At this point we need to send EXIT events to cpu contexts. | |
9987 | */ | |
9988 | perf_event_task(child, NULL, 0); | |
8dc85d54 PZ |
9989 | } |
9990 | ||
889ff015 FW |
9991 | static void perf_free_event(struct perf_event *event, |
9992 | struct perf_event_context *ctx) | |
9993 | { | |
9994 | struct perf_event *parent = event->parent; | |
9995 | ||
9996 | if (WARN_ON_ONCE(!parent)) | |
9997 | return; | |
9998 | ||
9999 | mutex_lock(&parent->child_mutex); | |
10000 | list_del_init(&event->child_list); | |
10001 | mutex_unlock(&parent->child_mutex); | |
10002 | ||
a6fa941d | 10003 | put_event(parent); |
889ff015 | 10004 | |
652884fe | 10005 | raw_spin_lock_irq(&ctx->lock); |
8a49542c | 10006 | perf_group_detach(event); |
889ff015 | 10007 | list_del_event(event, ctx); |
652884fe | 10008 | raw_spin_unlock_irq(&ctx->lock); |
889ff015 FW |
10009 | free_event(event); |
10010 | } | |
10011 | ||
bbbee908 | 10012 | /* |
652884fe | 10013 | * Free an unexposed, unused context as created by inheritance by |
8dc85d54 | 10014 | * perf_event_init_task below, used by fork() in case of fail. |
652884fe PZ |
10015 | * |
10016 | * Not all locks are strictly required, but take them anyway to be nice and | |
10017 | * help out with the lockdep assertions. | |
bbbee908 | 10018 | */ |
cdd6c482 | 10019 | void perf_event_free_task(struct task_struct *task) |
bbbee908 | 10020 | { |
8dc85d54 | 10021 | struct perf_event_context *ctx; |
cdd6c482 | 10022 | struct perf_event *event, *tmp; |
8dc85d54 | 10023 | int ctxn; |
bbbee908 | 10024 | |
8dc85d54 PZ |
10025 | for_each_task_context_nr(ctxn) { |
10026 | ctx = task->perf_event_ctxp[ctxn]; | |
10027 | if (!ctx) | |
10028 | continue; | |
bbbee908 | 10029 | |
8dc85d54 | 10030 | mutex_lock(&ctx->mutex); |
bbbee908 | 10031 | again: |
8dc85d54 PZ |
10032 | list_for_each_entry_safe(event, tmp, &ctx->pinned_groups, |
10033 | group_entry) | |
10034 | perf_free_event(event, ctx); | |
bbbee908 | 10035 | |
8dc85d54 PZ |
10036 | list_for_each_entry_safe(event, tmp, &ctx->flexible_groups, |
10037 | group_entry) | |
10038 | perf_free_event(event, ctx); | |
bbbee908 | 10039 | |
8dc85d54 PZ |
10040 | if (!list_empty(&ctx->pinned_groups) || |
10041 | !list_empty(&ctx->flexible_groups)) | |
10042 | goto again; | |
bbbee908 | 10043 | |
8dc85d54 | 10044 | mutex_unlock(&ctx->mutex); |
bbbee908 | 10045 | |
8dc85d54 PZ |
10046 | put_ctx(ctx); |
10047 | } | |
889ff015 FW |
10048 | } |
10049 | ||
4e231c79 PZ |
10050 | void perf_event_delayed_put(struct task_struct *task) |
10051 | { | |
10052 | int ctxn; | |
10053 | ||
10054 | for_each_task_context_nr(ctxn) | |
10055 | WARN_ON_ONCE(task->perf_event_ctxp[ctxn]); | |
10056 | } | |
10057 | ||
e03e7ee3 | 10058 | struct file *perf_event_get(unsigned int fd) |
ffe8690c | 10059 | { |
e03e7ee3 | 10060 | struct file *file; |
ffe8690c | 10061 | |
e03e7ee3 AS |
10062 | file = fget_raw(fd); |
10063 | if (!file) | |
10064 | return ERR_PTR(-EBADF); | |
ffe8690c | 10065 | |
e03e7ee3 AS |
10066 | if (file->f_op != &perf_fops) { |
10067 | fput(file); | |
10068 | return ERR_PTR(-EBADF); | |
10069 | } | |
ffe8690c | 10070 | |
e03e7ee3 | 10071 | return file; |
ffe8690c KX |
10072 | } |
10073 | ||
10074 | const struct perf_event_attr *perf_event_attrs(struct perf_event *event) | |
10075 | { | |
10076 | if (!event) | |
10077 | return ERR_PTR(-EINVAL); | |
10078 | ||
10079 | return &event->attr; | |
10080 | } | |
10081 | ||
97dee4f3 PZ |
10082 | /* |
10083 | * inherit a event from parent task to child task: | |
10084 | */ | |
10085 | static struct perf_event * | |
10086 | inherit_event(struct perf_event *parent_event, | |
10087 | struct task_struct *parent, | |
10088 | struct perf_event_context *parent_ctx, | |
10089 | struct task_struct *child, | |
10090 | struct perf_event *group_leader, | |
10091 | struct perf_event_context *child_ctx) | |
10092 | { | |
1929def9 | 10093 | enum perf_event_active_state parent_state = parent_event->state; |
97dee4f3 | 10094 | struct perf_event *child_event; |
cee010ec | 10095 | unsigned long flags; |
97dee4f3 PZ |
10096 | |
10097 | /* | |
10098 | * Instead of creating recursive hierarchies of events, | |
10099 | * we link inherited events back to the original parent, | |
10100 | * which has a filp for sure, which we use as the reference | |
10101 | * count: | |
10102 | */ | |
10103 | if (parent_event->parent) | |
10104 | parent_event = parent_event->parent; | |
10105 | ||
10106 | child_event = perf_event_alloc(&parent_event->attr, | |
10107 | parent_event->cpu, | |
d580ff86 | 10108 | child, |
97dee4f3 | 10109 | group_leader, parent_event, |
79dff51e | 10110 | NULL, NULL, -1); |
97dee4f3 PZ |
10111 | if (IS_ERR(child_event)) |
10112 | return child_event; | |
a6fa941d | 10113 | |
c6e5b732 PZ |
10114 | /* |
10115 | * is_orphaned_event() and list_add_tail(&parent_event->child_list) | |
10116 | * must be under the same lock in order to serialize against | |
10117 | * perf_event_release_kernel(), such that either we must observe | |
10118 | * is_orphaned_event() or they will observe us on the child_list. | |
10119 | */ | |
10120 | mutex_lock(&parent_event->child_mutex); | |
fadfe7be JO |
10121 | if (is_orphaned_event(parent_event) || |
10122 | !atomic_long_inc_not_zero(&parent_event->refcount)) { | |
c6e5b732 | 10123 | mutex_unlock(&parent_event->child_mutex); |
a6fa941d AV |
10124 | free_event(child_event); |
10125 | return NULL; | |
10126 | } | |
10127 | ||
97dee4f3 PZ |
10128 | get_ctx(child_ctx); |
10129 | ||
10130 | /* | |
10131 | * Make the child state follow the state of the parent event, | |
10132 | * not its attr.disabled bit. We hold the parent's mutex, | |
10133 | * so we won't race with perf_event_{en, dis}able_family. | |
10134 | */ | |
1929def9 | 10135 | if (parent_state >= PERF_EVENT_STATE_INACTIVE) |
97dee4f3 PZ |
10136 | child_event->state = PERF_EVENT_STATE_INACTIVE; |
10137 | else | |
10138 | child_event->state = PERF_EVENT_STATE_OFF; | |
10139 | ||
10140 | if (parent_event->attr.freq) { | |
10141 | u64 sample_period = parent_event->hw.sample_period; | |
10142 | struct hw_perf_event *hwc = &child_event->hw; | |
10143 | ||
10144 | hwc->sample_period = sample_period; | |
10145 | hwc->last_period = sample_period; | |
10146 | ||
10147 | local64_set(&hwc->period_left, sample_period); | |
10148 | } | |
10149 | ||
10150 | child_event->ctx = child_ctx; | |
10151 | child_event->overflow_handler = parent_event->overflow_handler; | |
4dc0da86 AK |
10152 | child_event->overflow_handler_context |
10153 | = parent_event->overflow_handler_context; | |
97dee4f3 | 10154 | |
614b6780 TG |
10155 | /* |
10156 | * Precalculate sample_data sizes | |
10157 | */ | |
10158 | perf_event__header_size(child_event); | |
6844c09d | 10159 | perf_event__id_header_size(child_event); |
614b6780 | 10160 | |
97dee4f3 PZ |
10161 | /* |
10162 | * Link it up in the child's context: | |
10163 | */ | |
cee010ec | 10164 | raw_spin_lock_irqsave(&child_ctx->lock, flags); |
97dee4f3 | 10165 | add_event_to_ctx(child_event, child_ctx); |
cee010ec | 10166 | raw_spin_unlock_irqrestore(&child_ctx->lock, flags); |
97dee4f3 | 10167 | |
97dee4f3 PZ |
10168 | /* |
10169 | * Link this into the parent event's child list | |
10170 | */ | |
97dee4f3 PZ |
10171 | list_add_tail(&child_event->child_list, &parent_event->child_list); |
10172 | mutex_unlock(&parent_event->child_mutex); | |
10173 | ||
10174 | return child_event; | |
10175 | } | |
10176 | ||
10177 | static int inherit_group(struct perf_event *parent_event, | |
10178 | struct task_struct *parent, | |
10179 | struct perf_event_context *parent_ctx, | |
10180 | struct task_struct *child, | |
10181 | struct perf_event_context *child_ctx) | |
10182 | { | |
10183 | struct perf_event *leader; | |
10184 | struct perf_event *sub; | |
10185 | struct perf_event *child_ctr; | |
10186 | ||
10187 | leader = inherit_event(parent_event, parent, parent_ctx, | |
10188 | child, NULL, child_ctx); | |
10189 | if (IS_ERR(leader)) | |
10190 | return PTR_ERR(leader); | |
10191 | list_for_each_entry(sub, &parent_event->sibling_list, group_entry) { | |
10192 | child_ctr = inherit_event(sub, parent, parent_ctx, | |
10193 | child, leader, child_ctx); | |
10194 | if (IS_ERR(child_ctr)) | |
10195 | return PTR_ERR(child_ctr); | |
10196 | } | |
10197 | return 0; | |
889ff015 FW |
10198 | } |
10199 | ||
10200 | static int | |
10201 | inherit_task_group(struct perf_event *event, struct task_struct *parent, | |
10202 | struct perf_event_context *parent_ctx, | |
8dc85d54 | 10203 | struct task_struct *child, int ctxn, |
889ff015 FW |
10204 | int *inherited_all) |
10205 | { | |
10206 | int ret; | |
8dc85d54 | 10207 | struct perf_event_context *child_ctx; |
889ff015 FW |
10208 | |
10209 | if (!event->attr.inherit) { | |
10210 | *inherited_all = 0; | |
10211 | return 0; | |
bbbee908 PZ |
10212 | } |
10213 | ||
fe4b04fa | 10214 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 FW |
10215 | if (!child_ctx) { |
10216 | /* | |
10217 | * This is executed from the parent task context, so | |
10218 | * inherit events that have been marked for cloning. | |
10219 | * First allocate and initialize a context for the | |
10220 | * child. | |
10221 | */ | |
bbbee908 | 10222 | |
734df5ab | 10223 | child_ctx = alloc_perf_context(parent_ctx->pmu, child); |
889ff015 FW |
10224 | if (!child_ctx) |
10225 | return -ENOMEM; | |
bbbee908 | 10226 | |
8dc85d54 | 10227 | child->perf_event_ctxp[ctxn] = child_ctx; |
889ff015 FW |
10228 | } |
10229 | ||
10230 | ret = inherit_group(event, parent, parent_ctx, | |
10231 | child, child_ctx); | |
10232 | ||
10233 | if (ret) | |
10234 | *inherited_all = 0; | |
10235 | ||
10236 | return ret; | |
bbbee908 PZ |
10237 | } |
10238 | ||
9b51f66d | 10239 | /* |
cdd6c482 | 10240 | * Initialize the perf_event context in task_struct |
9b51f66d | 10241 | */ |
985c8dcb | 10242 | static int perf_event_init_context(struct task_struct *child, int ctxn) |
9b51f66d | 10243 | { |
889ff015 | 10244 | struct perf_event_context *child_ctx, *parent_ctx; |
cdd6c482 IM |
10245 | struct perf_event_context *cloned_ctx; |
10246 | struct perf_event *event; | |
9b51f66d | 10247 | struct task_struct *parent = current; |
564c2b21 | 10248 | int inherited_all = 1; |
dddd3379 | 10249 | unsigned long flags; |
6ab423e0 | 10250 | int ret = 0; |
9b51f66d | 10251 | |
8dc85d54 | 10252 | if (likely(!parent->perf_event_ctxp[ctxn])) |
6ab423e0 PZ |
10253 | return 0; |
10254 | ||
ad3a37de | 10255 | /* |
25346b93 PM |
10256 | * If the parent's context is a clone, pin it so it won't get |
10257 | * swapped under us. | |
ad3a37de | 10258 | */ |
8dc85d54 | 10259 | parent_ctx = perf_pin_task_context(parent, ctxn); |
ffb4ef21 PZ |
10260 | if (!parent_ctx) |
10261 | return 0; | |
25346b93 | 10262 | |
ad3a37de PM |
10263 | /* |
10264 | * No need to check if parent_ctx != NULL here; since we saw | |
10265 | * it non-NULL earlier, the only reason for it to become NULL | |
10266 | * is if we exit, and since we're currently in the middle of | |
10267 | * a fork we can't be exiting at the same time. | |
10268 | */ | |
ad3a37de | 10269 | |
9b51f66d IM |
10270 | /* |
10271 | * Lock the parent list. No need to lock the child - not PID | |
10272 | * hashed yet and not running, so nobody can access it. | |
10273 | */ | |
d859e29f | 10274 | mutex_lock(&parent_ctx->mutex); |
9b51f66d IM |
10275 | |
10276 | /* | |
10277 | * We dont have to disable NMIs - we are only looking at | |
10278 | * the list, not manipulating it: | |
10279 | */ | |
889ff015 | 10280 | list_for_each_entry(event, &parent_ctx->pinned_groups, group_entry) { |
8dc85d54 PZ |
10281 | ret = inherit_task_group(event, parent, parent_ctx, |
10282 | child, ctxn, &inherited_all); | |
889ff015 FW |
10283 | if (ret) |
10284 | break; | |
10285 | } | |
b93f7978 | 10286 | |
dddd3379 TG |
10287 | /* |
10288 | * We can't hold ctx->lock when iterating the ->flexible_group list due | |
10289 | * to allocations, but we need to prevent rotation because | |
10290 | * rotate_ctx() will change the list from interrupt context. | |
10291 | */ | |
10292 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); | |
10293 | parent_ctx->rotate_disable = 1; | |
10294 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); | |
10295 | ||
889ff015 | 10296 | list_for_each_entry(event, &parent_ctx->flexible_groups, group_entry) { |
8dc85d54 PZ |
10297 | ret = inherit_task_group(event, parent, parent_ctx, |
10298 | child, ctxn, &inherited_all); | |
889ff015 | 10299 | if (ret) |
9b51f66d | 10300 | break; |
564c2b21 PM |
10301 | } |
10302 | ||
dddd3379 TG |
10303 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); |
10304 | parent_ctx->rotate_disable = 0; | |
dddd3379 | 10305 | |
8dc85d54 | 10306 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 | 10307 | |
05cbaa28 | 10308 | if (child_ctx && inherited_all) { |
564c2b21 PM |
10309 | /* |
10310 | * Mark the child context as a clone of the parent | |
10311 | * context, or of whatever the parent is a clone of. | |
c5ed5145 PZ |
10312 | * |
10313 | * Note that if the parent is a clone, the holding of | |
10314 | * parent_ctx->lock avoids it from being uncloned. | |
564c2b21 | 10315 | */ |
c5ed5145 | 10316 | cloned_ctx = parent_ctx->parent_ctx; |
ad3a37de PM |
10317 | if (cloned_ctx) { |
10318 | child_ctx->parent_ctx = cloned_ctx; | |
25346b93 | 10319 | child_ctx->parent_gen = parent_ctx->parent_gen; |
564c2b21 PM |
10320 | } else { |
10321 | child_ctx->parent_ctx = parent_ctx; | |
10322 | child_ctx->parent_gen = parent_ctx->generation; | |
10323 | } | |
10324 | get_ctx(child_ctx->parent_ctx); | |
9b51f66d IM |
10325 | } |
10326 | ||
c5ed5145 | 10327 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); |
d859e29f | 10328 | mutex_unlock(&parent_ctx->mutex); |
6ab423e0 | 10329 | |
25346b93 | 10330 | perf_unpin_context(parent_ctx); |
fe4b04fa | 10331 | put_ctx(parent_ctx); |
ad3a37de | 10332 | |
6ab423e0 | 10333 | return ret; |
9b51f66d IM |
10334 | } |
10335 | ||
8dc85d54 PZ |
10336 | /* |
10337 | * Initialize the perf_event context in task_struct | |
10338 | */ | |
10339 | int perf_event_init_task(struct task_struct *child) | |
10340 | { | |
10341 | int ctxn, ret; | |
10342 | ||
8550d7cb ON |
10343 | memset(child->perf_event_ctxp, 0, sizeof(child->perf_event_ctxp)); |
10344 | mutex_init(&child->perf_event_mutex); | |
10345 | INIT_LIST_HEAD(&child->perf_event_list); | |
10346 | ||
8dc85d54 PZ |
10347 | for_each_task_context_nr(ctxn) { |
10348 | ret = perf_event_init_context(child, ctxn); | |
6c72e350 PZ |
10349 | if (ret) { |
10350 | perf_event_free_task(child); | |
8dc85d54 | 10351 | return ret; |
6c72e350 | 10352 | } |
8dc85d54 PZ |
10353 | } |
10354 | ||
10355 | return 0; | |
10356 | } | |
10357 | ||
220b140b PM |
10358 | static void __init perf_event_init_all_cpus(void) |
10359 | { | |
b28ab83c | 10360 | struct swevent_htable *swhash; |
220b140b | 10361 | int cpu; |
220b140b PM |
10362 | |
10363 | for_each_possible_cpu(cpu) { | |
b28ab83c PZ |
10364 | swhash = &per_cpu(swevent_htable, cpu); |
10365 | mutex_init(&swhash->hlist_mutex); | |
2fde4f94 | 10366 | INIT_LIST_HEAD(&per_cpu(active_ctx_list, cpu)); |
f2fb6bef KL |
10367 | |
10368 | INIT_LIST_HEAD(&per_cpu(pmu_sb_events.list, cpu)); | |
10369 | raw_spin_lock_init(&per_cpu(pmu_sb_events.lock, cpu)); | |
220b140b PM |
10370 | } |
10371 | } | |
10372 | ||
00e16c3d | 10373 | int perf_event_init_cpu(unsigned int cpu) |
0793a61d | 10374 | { |
108b02cf | 10375 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
0793a61d | 10376 | |
b28ab83c | 10377 | mutex_lock(&swhash->hlist_mutex); |
059fcd8c | 10378 | if (swhash->hlist_refcount > 0 && !swevent_hlist_deref(swhash)) { |
76e1d904 FW |
10379 | struct swevent_hlist *hlist; |
10380 | ||
b28ab83c PZ |
10381 | hlist = kzalloc_node(sizeof(*hlist), GFP_KERNEL, cpu_to_node(cpu)); |
10382 | WARN_ON(!hlist); | |
10383 | rcu_assign_pointer(swhash->swevent_hlist, hlist); | |
76e1d904 | 10384 | } |
b28ab83c | 10385 | mutex_unlock(&swhash->hlist_mutex); |
00e16c3d | 10386 | return 0; |
0793a61d TG |
10387 | } |
10388 | ||
2965faa5 | 10389 | #if defined CONFIG_HOTPLUG_CPU || defined CONFIG_KEXEC_CORE |
108b02cf | 10390 | static void __perf_event_exit_context(void *__info) |
0793a61d | 10391 | { |
108b02cf | 10392 | struct perf_event_context *ctx = __info; |
fae3fde6 PZ |
10393 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
10394 | struct perf_event *event; | |
0793a61d | 10395 | |
fae3fde6 PZ |
10396 | raw_spin_lock(&ctx->lock); |
10397 | list_for_each_entry(event, &ctx->event_list, event_entry) | |
45a0e07a | 10398 | __perf_remove_from_context(event, cpuctx, ctx, (void *)DETACH_GROUP); |
fae3fde6 | 10399 | raw_spin_unlock(&ctx->lock); |
0793a61d | 10400 | } |
108b02cf PZ |
10401 | |
10402 | static void perf_event_exit_cpu_context(int cpu) | |
10403 | { | |
10404 | struct perf_event_context *ctx; | |
10405 | struct pmu *pmu; | |
10406 | int idx; | |
10407 | ||
10408 | idx = srcu_read_lock(&pmus_srcu); | |
10409 | list_for_each_entry_rcu(pmu, &pmus, entry) { | |
917bdd1c | 10410 | ctx = &per_cpu_ptr(pmu->pmu_cpu_context, cpu)->ctx; |
108b02cf PZ |
10411 | |
10412 | mutex_lock(&ctx->mutex); | |
10413 | smp_call_function_single(cpu, __perf_event_exit_context, ctx, 1); | |
10414 | mutex_unlock(&ctx->mutex); | |
10415 | } | |
10416 | srcu_read_unlock(&pmus_srcu, idx); | |
108b02cf | 10417 | } |
00e16c3d TG |
10418 | #else |
10419 | ||
10420 | static void perf_event_exit_cpu_context(int cpu) { } | |
10421 | ||
10422 | #endif | |
108b02cf | 10423 | |
00e16c3d | 10424 | int perf_event_exit_cpu(unsigned int cpu) |
0793a61d | 10425 | { |
e3703f8c | 10426 | perf_event_exit_cpu_context(cpu); |
00e16c3d | 10427 | return 0; |
0793a61d | 10428 | } |
0793a61d | 10429 | |
c277443c PZ |
10430 | static int |
10431 | perf_reboot(struct notifier_block *notifier, unsigned long val, void *v) | |
10432 | { | |
10433 | int cpu; | |
10434 | ||
10435 | for_each_online_cpu(cpu) | |
10436 | perf_event_exit_cpu(cpu); | |
10437 | ||
10438 | return NOTIFY_OK; | |
10439 | } | |
10440 | ||
10441 | /* | |
10442 | * Run the perf reboot notifier at the very last possible moment so that | |
10443 | * the generic watchdog code runs as long as possible. | |
10444 | */ | |
10445 | static struct notifier_block perf_reboot_notifier = { | |
10446 | .notifier_call = perf_reboot, | |
10447 | .priority = INT_MIN, | |
10448 | }; | |
10449 | ||
cdd6c482 | 10450 | void __init perf_event_init(void) |
0793a61d | 10451 | { |
3c502e7a JW |
10452 | int ret; |
10453 | ||
2e80a82a PZ |
10454 | idr_init(&pmu_idr); |
10455 | ||
220b140b | 10456 | perf_event_init_all_cpus(); |
b0a873eb | 10457 | init_srcu_struct(&pmus_srcu); |
2e80a82a PZ |
10458 | perf_pmu_register(&perf_swevent, "software", PERF_TYPE_SOFTWARE); |
10459 | perf_pmu_register(&perf_cpu_clock, NULL, -1); | |
10460 | perf_pmu_register(&perf_task_clock, NULL, -1); | |
b0a873eb | 10461 | perf_tp_register(); |
00e16c3d | 10462 | perf_event_init_cpu(smp_processor_id()); |
c277443c | 10463 | register_reboot_notifier(&perf_reboot_notifier); |
3c502e7a JW |
10464 | |
10465 | ret = init_hw_breakpoint(); | |
10466 | WARN(ret, "hw_breakpoint initialization failed with: %d", ret); | |
b2029520 | 10467 | |
b01c3a00 JO |
10468 | /* |
10469 | * Build time assertion that we keep the data_head at the intended | |
10470 | * location. IOW, validation we got the __reserved[] size right. | |
10471 | */ | |
10472 | BUILD_BUG_ON((offsetof(struct perf_event_mmap_page, data_head)) | |
10473 | != 1024); | |
0793a61d | 10474 | } |
abe43400 | 10475 | |
fd979c01 CS |
10476 | ssize_t perf_event_sysfs_show(struct device *dev, struct device_attribute *attr, |
10477 | char *page) | |
10478 | { | |
10479 | struct perf_pmu_events_attr *pmu_attr = | |
10480 | container_of(attr, struct perf_pmu_events_attr, attr); | |
10481 | ||
10482 | if (pmu_attr->event_str) | |
10483 | return sprintf(page, "%s\n", pmu_attr->event_str); | |
10484 | ||
10485 | return 0; | |
10486 | } | |
675965b0 | 10487 | EXPORT_SYMBOL_GPL(perf_event_sysfs_show); |
fd979c01 | 10488 | |
abe43400 PZ |
10489 | static int __init perf_event_sysfs_init(void) |
10490 | { | |
10491 | struct pmu *pmu; | |
10492 | int ret; | |
10493 | ||
10494 | mutex_lock(&pmus_lock); | |
10495 | ||
10496 | ret = bus_register(&pmu_bus); | |
10497 | if (ret) | |
10498 | goto unlock; | |
10499 | ||
10500 | list_for_each_entry(pmu, &pmus, entry) { | |
10501 | if (!pmu->name || pmu->type < 0) | |
10502 | continue; | |
10503 | ||
10504 | ret = pmu_dev_alloc(pmu); | |
10505 | WARN(ret, "Failed to register pmu: %s, reason %d\n", pmu->name, ret); | |
10506 | } | |
10507 | pmu_bus_running = 1; | |
10508 | ret = 0; | |
10509 | ||
10510 | unlock: | |
10511 | mutex_unlock(&pmus_lock); | |
10512 | ||
10513 | return ret; | |
10514 | } | |
10515 | device_initcall(perf_event_sysfs_init); | |
e5d1367f SE |
10516 | |
10517 | #ifdef CONFIG_CGROUP_PERF | |
eb95419b TH |
10518 | static struct cgroup_subsys_state * |
10519 | perf_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) | |
e5d1367f SE |
10520 | { |
10521 | struct perf_cgroup *jc; | |
e5d1367f | 10522 | |
1b15d055 | 10523 | jc = kzalloc(sizeof(*jc), GFP_KERNEL); |
e5d1367f SE |
10524 | if (!jc) |
10525 | return ERR_PTR(-ENOMEM); | |
10526 | ||
e5d1367f SE |
10527 | jc->info = alloc_percpu(struct perf_cgroup_info); |
10528 | if (!jc->info) { | |
10529 | kfree(jc); | |
10530 | return ERR_PTR(-ENOMEM); | |
10531 | } | |
10532 | ||
e5d1367f SE |
10533 | return &jc->css; |
10534 | } | |
10535 | ||
eb95419b | 10536 | static void perf_cgroup_css_free(struct cgroup_subsys_state *css) |
e5d1367f | 10537 | { |
eb95419b TH |
10538 | struct perf_cgroup *jc = container_of(css, struct perf_cgroup, css); |
10539 | ||
e5d1367f SE |
10540 | free_percpu(jc->info); |
10541 | kfree(jc); | |
10542 | } | |
10543 | ||
10544 | static int __perf_cgroup_move(void *info) | |
10545 | { | |
10546 | struct task_struct *task = info; | |
ddaaf4e2 | 10547 | rcu_read_lock(); |
e5d1367f | 10548 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT | PERF_CGROUP_SWIN); |
ddaaf4e2 | 10549 | rcu_read_unlock(); |
e5d1367f SE |
10550 | return 0; |
10551 | } | |
10552 | ||
1f7dd3e5 | 10553 | static void perf_cgroup_attach(struct cgroup_taskset *tset) |
e5d1367f | 10554 | { |
bb9d97b6 | 10555 | struct task_struct *task; |
1f7dd3e5 | 10556 | struct cgroup_subsys_state *css; |
bb9d97b6 | 10557 | |
1f7dd3e5 | 10558 | cgroup_taskset_for_each(task, css, tset) |
bb9d97b6 | 10559 | task_function_call(task, __perf_cgroup_move, task); |
e5d1367f SE |
10560 | } |
10561 | ||
073219e9 | 10562 | struct cgroup_subsys perf_event_cgrp_subsys = { |
92fb9748 TH |
10563 | .css_alloc = perf_cgroup_css_alloc, |
10564 | .css_free = perf_cgroup_css_free, | |
bb9d97b6 | 10565 | .attach = perf_cgroup_attach, |
e5d1367f SE |
10566 | }; |
10567 | #endif /* CONFIG_CGROUP_PERF */ |