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Commit | Line | Data |
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0793a61d | 1 | /* |
57c0c15b | 2 | * Performance events core code: |
0793a61d | 3 | * |
98144511 | 4 | * Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de> |
e7e7ee2e | 5 | * Copyright (C) 2008-2011 Red Hat, Inc., Ingo Molnar |
90eec103 | 6 | * Copyright (C) 2008-2011 Red Hat, Inc., Peter Zijlstra |
d36b6910 | 7 | * Copyright © 2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com> |
7b732a75 | 8 | * |
57c0c15b | 9 | * For licensing details see kernel-base/COPYING |
0793a61d TG |
10 | */ |
11 | ||
12 | #include <linux/fs.h> | |
b9cacc7b | 13 | #include <linux/mm.h> |
0793a61d TG |
14 | #include <linux/cpu.h> |
15 | #include <linux/smp.h> | |
2e80a82a | 16 | #include <linux/idr.h> |
04289bb9 | 17 | #include <linux/file.h> |
0793a61d | 18 | #include <linux/poll.h> |
5a0e3ad6 | 19 | #include <linux/slab.h> |
76e1d904 | 20 | #include <linux/hash.h> |
12351ef8 | 21 | #include <linux/tick.h> |
0793a61d | 22 | #include <linux/sysfs.h> |
22a4f650 | 23 | #include <linux/dcache.h> |
0793a61d | 24 | #include <linux/percpu.h> |
22a4f650 | 25 | #include <linux/ptrace.h> |
c277443c | 26 | #include <linux/reboot.h> |
b9cacc7b | 27 | #include <linux/vmstat.h> |
abe43400 | 28 | #include <linux/device.h> |
6e5fdeed | 29 | #include <linux/export.h> |
906010b2 | 30 | #include <linux/vmalloc.h> |
b9cacc7b PZ |
31 | #include <linux/hardirq.h> |
32 | #include <linux/rculist.h> | |
0793a61d TG |
33 | #include <linux/uaccess.h> |
34 | #include <linux/syscalls.h> | |
35 | #include <linux/anon_inodes.h> | |
aa9c4c0f | 36 | #include <linux/kernel_stat.h> |
39bed6cb | 37 | #include <linux/cgroup.h> |
cdd6c482 | 38 | #include <linux/perf_event.h> |
af658dca | 39 | #include <linux/trace_events.h> |
3c502e7a | 40 | #include <linux/hw_breakpoint.h> |
c5ebcedb | 41 | #include <linux/mm_types.h> |
c464c76e | 42 | #include <linux/module.h> |
f972eb63 | 43 | #include <linux/mman.h> |
b3f20785 | 44 | #include <linux/compat.h> |
2541517c AS |
45 | #include <linux/bpf.h> |
46 | #include <linux/filter.h> | |
375637bc AS |
47 | #include <linux/namei.h> |
48 | #include <linux/parser.h> | |
e6017571 | 49 | #include <linux/sched/clock.h> |
6e84f315 | 50 | #include <linux/sched/mm.h> |
e4222673 HB |
51 | #include <linux/proc_ns.h> |
52 | #include <linux/mount.h> | |
0793a61d | 53 | |
76369139 FW |
54 | #include "internal.h" |
55 | ||
4e193bd4 TB |
56 | #include <asm/irq_regs.h> |
57 | ||
272325c4 PZ |
58 | typedef int (*remote_function_f)(void *); |
59 | ||
fe4b04fa | 60 | struct remote_function_call { |
e7e7ee2e | 61 | struct task_struct *p; |
272325c4 | 62 | remote_function_f func; |
e7e7ee2e IM |
63 | void *info; |
64 | int ret; | |
fe4b04fa PZ |
65 | }; |
66 | ||
67 | static void remote_function(void *data) | |
68 | { | |
69 | struct remote_function_call *tfc = data; | |
70 | struct task_struct *p = tfc->p; | |
71 | ||
72 | if (p) { | |
0da4cf3e PZ |
73 | /* -EAGAIN */ |
74 | if (task_cpu(p) != smp_processor_id()) | |
75 | return; | |
76 | ||
77 | /* | |
78 | * Now that we're on right CPU with IRQs disabled, we can test | |
79 | * if we hit the right task without races. | |
80 | */ | |
81 | ||
82 | tfc->ret = -ESRCH; /* No such (running) process */ | |
83 | if (p != current) | |
fe4b04fa PZ |
84 | return; |
85 | } | |
86 | ||
87 | tfc->ret = tfc->func(tfc->info); | |
88 | } | |
89 | ||
90 | /** | |
91 | * task_function_call - call a function on the cpu on which a task runs | |
92 | * @p: the task to evaluate | |
93 | * @func: the function to be called | |
94 | * @info: the function call argument | |
95 | * | |
96 | * Calls the function @func when the task is currently running. This might | |
97 | * be on the current CPU, which just calls the function directly | |
98 | * | |
99 | * returns: @func return value, or | |
100 | * -ESRCH - when the process isn't running | |
101 | * -EAGAIN - when the process moved away | |
102 | */ | |
103 | static int | |
272325c4 | 104 | task_function_call(struct task_struct *p, remote_function_f func, void *info) |
fe4b04fa PZ |
105 | { |
106 | struct remote_function_call data = { | |
e7e7ee2e IM |
107 | .p = p, |
108 | .func = func, | |
109 | .info = info, | |
0da4cf3e | 110 | .ret = -EAGAIN, |
fe4b04fa | 111 | }; |
0da4cf3e | 112 | int ret; |
fe4b04fa | 113 | |
0da4cf3e PZ |
114 | do { |
115 | ret = smp_call_function_single(task_cpu(p), remote_function, &data, 1); | |
116 | if (!ret) | |
117 | ret = data.ret; | |
118 | } while (ret == -EAGAIN); | |
fe4b04fa | 119 | |
0da4cf3e | 120 | return ret; |
fe4b04fa PZ |
121 | } |
122 | ||
123 | /** | |
124 | * cpu_function_call - call a function on the cpu | |
125 | * @func: the function to be called | |
126 | * @info: the function call argument | |
127 | * | |
128 | * Calls the function @func on the remote cpu. | |
129 | * | |
130 | * returns: @func return value or -ENXIO when the cpu is offline | |
131 | */ | |
272325c4 | 132 | static int cpu_function_call(int cpu, remote_function_f func, void *info) |
fe4b04fa PZ |
133 | { |
134 | struct remote_function_call data = { | |
e7e7ee2e IM |
135 | .p = NULL, |
136 | .func = func, | |
137 | .info = info, | |
138 | .ret = -ENXIO, /* No such CPU */ | |
fe4b04fa PZ |
139 | }; |
140 | ||
141 | smp_call_function_single(cpu, remote_function, &data, 1); | |
142 | ||
143 | return data.ret; | |
144 | } | |
145 | ||
fae3fde6 PZ |
146 | static inline struct perf_cpu_context * |
147 | __get_cpu_context(struct perf_event_context *ctx) | |
148 | { | |
149 | return this_cpu_ptr(ctx->pmu->pmu_cpu_context); | |
150 | } | |
151 | ||
152 | static void perf_ctx_lock(struct perf_cpu_context *cpuctx, | |
153 | struct perf_event_context *ctx) | |
0017960f | 154 | { |
fae3fde6 PZ |
155 | raw_spin_lock(&cpuctx->ctx.lock); |
156 | if (ctx) | |
157 | raw_spin_lock(&ctx->lock); | |
158 | } | |
159 | ||
160 | static void perf_ctx_unlock(struct perf_cpu_context *cpuctx, | |
161 | struct perf_event_context *ctx) | |
162 | { | |
163 | if (ctx) | |
164 | raw_spin_unlock(&ctx->lock); | |
165 | raw_spin_unlock(&cpuctx->ctx.lock); | |
166 | } | |
167 | ||
63b6da39 PZ |
168 | #define TASK_TOMBSTONE ((void *)-1L) |
169 | ||
170 | static bool is_kernel_event(struct perf_event *event) | |
171 | { | |
f47c02c0 | 172 | return READ_ONCE(event->owner) == TASK_TOMBSTONE; |
63b6da39 PZ |
173 | } |
174 | ||
39a43640 PZ |
175 | /* |
176 | * On task ctx scheduling... | |
177 | * | |
178 | * When !ctx->nr_events a task context will not be scheduled. This means | |
179 | * we can disable the scheduler hooks (for performance) without leaving | |
180 | * pending task ctx state. | |
181 | * | |
182 | * This however results in two special cases: | |
183 | * | |
184 | * - removing the last event from a task ctx; this is relatively straight | |
185 | * forward and is done in __perf_remove_from_context. | |
186 | * | |
187 | * - adding the first event to a task ctx; this is tricky because we cannot | |
188 | * rely on ctx->is_active and therefore cannot use event_function_call(). | |
189 | * See perf_install_in_context(). | |
190 | * | |
39a43640 PZ |
191 | * If ctx->nr_events, then ctx->is_active and cpuctx->task_ctx are set. |
192 | */ | |
193 | ||
fae3fde6 PZ |
194 | typedef void (*event_f)(struct perf_event *, struct perf_cpu_context *, |
195 | struct perf_event_context *, void *); | |
196 | ||
197 | struct event_function_struct { | |
198 | struct perf_event *event; | |
199 | event_f func; | |
200 | void *data; | |
201 | }; | |
202 | ||
203 | static int event_function(void *info) | |
204 | { | |
205 | struct event_function_struct *efs = info; | |
206 | struct perf_event *event = efs->event; | |
0017960f | 207 | struct perf_event_context *ctx = event->ctx; |
fae3fde6 PZ |
208 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
209 | struct perf_event_context *task_ctx = cpuctx->task_ctx; | |
63b6da39 | 210 | int ret = 0; |
fae3fde6 | 211 | |
16444645 | 212 | lockdep_assert_irqs_disabled(); |
fae3fde6 | 213 | |
63b6da39 | 214 | perf_ctx_lock(cpuctx, task_ctx); |
fae3fde6 PZ |
215 | /* |
216 | * Since we do the IPI call without holding ctx->lock things can have | |
217 | * changed, double check we hit the task we set out to hit. | |
fae3fde6 PZ |
218 | */ |
219 | if (ctx->task) { | |
63b6da39 | 220 | if (ctx->task != current) { |
0da4cf3e | 221 | ret = -ESRCH; |
63b6da39 PZ |
222 | goto unlock; |
223 | } | |
fae3fde6 | 224 | |
fae3fde6 PZ |
225 | /* |
226 | * We only use event_function_call() on established contexts, | |
227 | * and event_function() is only ever called when active (or | |
228 | * rather, we'll have bailed in task_function_call() or the | |
229 | * above ctx->task != current test), therefore we must have | |
230 | * ctx->is_active here. | |
231 | */ | |
232 | WARN_ON_ONCE(!ctx->is_active); | |
233 | /* | |
234 | * And since we have ctx->is_active, cpuctx->task_ctx must | |
235 | * match. | |
236 | */ | |
63b6da39 PZ |
237 | WARN_ON_ONCE(task_ctx != ctx); |
238 | } else { | |
239 | WARN_ON_ONCE(&cpuctx->ctx != ctx); | |
fae3fde6 | 240 | } |
63b6da39 | 241 | |
fae3fde6 | 242 | efs->func(event, cpuctx, ctx, efs->data); |
63b6da39 | 243 | unlock: |
fae3fde6 PZ |
244 | perf_ctx_unlock(cpuctx, task_ctx); |
245 | ||
63b6da39 | 246 | return ret; |
fae3fde6 PZ |
247 | } |
248 | ||
fae3fde6 | 249 | static void event_function_call(struct perf_event *event, event_f func, void *data) |
0017960f PZ |
250 | { |
251 | struct perf_event_context *ctx = event->ctx; | |
63b6da39 | 252 | struct task_struct *task = READ_ONCE(ctx->task); /* verified in event_function */ |
fae3fde6 PZ |
253 | struct event_function_struct efs = { |
254 | .event = event, | |
255 | .func = func, | |
256 | .data = data, | |
257 | }; | |
0017960f | 258 | |
c97f4736 PZ |
259 | if (!event->parent) { |
260 | /* | |
261 | * If this is a !child event, we must hold ctx::mutex to | |
262 | * stabilize the the event->ctx relation. See | |
263 | * perf_event_ctx_lock(). | |
264 | */ | |
265 | lockdep_assert_held(&ctx->mutex); | |
266 | } | |
0017960f PZ |
267 | |
268 | if (!task) { | |
fae3fde6 | 269 | cpu_function_call(event->cpu, event_function, &efs); |
0017960f PZ |
270 | return; |
271 | } | |
272 | ||
63b6da39 PZ |
273 | if (task == TASK_TOMBSTONE) |
274 | return; | |
275 | ||
a096309b | 276 | again: |
fae3fde6 | 277 | if (!task_function_call(task, event_function, &efs)) |
0017960f PZ |
278 | return; |
279 | ||
280 | raw_spin_lock_irq(&ctx->lock); | |
63b6da39 PZ |
281 | /* |
282 | * Reload the task pointer, it might have been changed by | |
283 | * a concurrent perf_event_context_sched_out(). | |
284 | */ | |
285 | task = ctx->task; | |
a096309b PZ |
286 | if (task == TASK_TOMBSTONE) { |
287 | raw_spin_unlock_irq(&ctx->lock); | |
288 | return; | |
0017960f | 289 | } |
a096309b PZ |
290 | if (ctx->is_active) { |
291 | raw_spin_unlock_irq(&ctx->lock); | |
292 | goto again; | |
293 | } | |
294 | func(event, NULL, ctx, data); | |
0017960f PZ |
295 | raw_spin_unlock_irq(&ctx->lock); |
296 | } | |
297 | ||
cca20946 PZ |
298 | /* |
299 | * Similar to event_function_call() + event_function(), but hard assumes IRQs | |
300 | * are already disabled and we're on the right CPU. | |
301 | */ | |
302 | static void event_function_local(struct perf_event *event, event_f func, void *data) | |
303 | { | |
304 | struct perf_event_context *ctx = event->ctx; | |
305 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
306 | struct task_struct *task = READ_ONCE(ctx->task); | |
307 | struct perf_event_context *task_ctx = NULL; | |
308 | ||
16444645 | 309 | lockdep_assert_irqs_disabled(); |
cca20946 PZ |
310 | |
311 | if (task) { | |
312 | if (task == TASK_TOMBSTONE) | |
313 | return; | |
314 | ||
315 | task_ctx = ctx; | |
316 | } | |
317 | ||
318 | perf_ctx_lock(cpuctx, task_ctx); | |
319 | ||
320 | task = ctx->task; | |
321 | if (task == TASK_TOMBSTONE) | |
322 | goto unlock; | |
323 | ||
324 | if (task) { | |
325 | /* | |
326 | * We must be either inactive or active and the right task, | |
327 | * otherwise we're screwed, since we cannot IPI to somewhere | |
328 | * else. | |
329 | */ | |
330 | if (ctx->is_active) { | |
331 | if (WARN_ON_ONCE(task != current)) | |
332 | goto unlock; | |
333 | ||
334 | if (WARN_ON_ONCE(cpuctx->task_ctx != ctx)) | |
335 | goto unlock; | |
336 | } | |
337 | } else { | |
338 | WARN_ON_ONCE(&cpuctx->ctx != ctx); | |
339 | } | |
340 | ||
341 | func(event, cpuctx, ctx, data); | |
342 | unlock: | |
343 | perf_ctx_unlock(cpuctx, task_ctx); | |
344 | } | |
345 | ||
e5d1367f SE |
346 | #define PERF_FLAG_ALL (PERF_FLAG_FD_NO_GROUP |\ |
347 | PERF_FLAG_FD_OUTPUT |\ | |
a21b0b35 YD |
348 | PERF_FLAG_PID_CGROUP |\ |
349 | PERF_FLAG_FD_CLOEXEC) | |
e5d1367f | 350 | |
bce38cd5 SE |
351 | /* |
352 | * branch priv levels that need permission checks | |
353 | */ | |
354 | #define PERF_SAMPLE_BRANCH_PERM_PLM \ | |
355 | (PERF_SAMPLE_BRANCH_KERNEL |\ | |
356 | PERF_SAMPLE_BRANCH_HV) | |
357 | ||
0b3fcf17 SE |
358 | enum event_type_t { |
359 | EVENT_FLEXIBLE = 0x1, | |
360 | EVENT_PINNED = 0x2, | |
3cbaa590 | 361 | EVENT_TIME = 0x4, |
487f05e1 AS |
362 | /* see ctx_resched() for details */ |
363 | EVENT_CPU = 0x8, | |
0b3fcf17 SE |
364 | EVENT_ALL = EVENT_FLEXIBLE | EVENT_PINNED, |
365 | }; | |
366 | ||
e5d1367f SE |
367 | /* |
368 | * perf_sched_events : >0 events exist | |
369 | * perf_cgroup_events: >0 per-cpu cgroup events exist on this cpu | |
370 | */ | |
9107c89e PZ |
371 | |
372 | static void perf_sched_delayed(struct work_struct *work); | |
373 | DEFINE_STATIC_KEY_FALSE(perf_sched_events); | |
374 | static DECLARE_DELAYED_WORK(perf_sched_work, perf_sched_delayed); | |
375 | static DEFINE_MUTEX(perf_sched_mutex); | |
376 | static atomic_t perf_sched_count; | |
377 | ||
e5d1367f | 378 | static DEFINE_PER_CPU(atomic_t, perf_cgroup_events); |
ba532500 | 379 | static DEFINE_PER_CPU(int, perf_sched_cb_usages); |
f2fb6bef | 380 | static DEFINE_PER_CPU(struct pmu_event_list, pmu_sb_events); |
e5d1367f | 381 | |
cdd6c482 IM |
382 | static atomic_t nr_mmap_events __read_mostly; |
383 | static atomic_t nr_comm_events __read_mostly; | |
e4222673 | 384 | static atomic_t nr_namespaces_events __read_mostly; |
cdd6c482 | 385 | static atomic_t nr_task_events __read_mostly; |
948b26b6 | 386 | static atomic_t nr_freq_events __read_mostly; |
45ac1403 | 387 | static atomic_t nr_switch_events __read_mostly; |
9ee318a7 | 388 | |
108b02cf PZ |
389 | static LIST_HEAD(pmus); |
390 | static DEFINE_MUTEX(pmus_lock); | |
391 | static struct srcu_struct pmus_srcu; | |
a63fbed7 | 392 | static cpumask_var_t perf_online_mask; |
108b02cf | 393 | |
0764771d | 394 | /* |
cdd6c482 | 395 | * perf event paranoia level: |
0fbdea19 IM |
396 | * -1 - not paranoid at all |
397 | * 0 - disallow raw tracepoint access for unpriv | |
cdd6c482 | 398 | * 1 - disallow cpu events for unpriv |
0fbdea19 | 399 | * 2 - disallow kernel profiling for unpriv |
d48d0c64 | 400 | * 3 - disallow all unpriv perf event use |
0764771d | 401 | */ |
d48d0c64 BH |
402 | #ifdef CONFIG_SECURITY_PERF_EVENTS_RESTRICT |
403 | int sysctl_perf_event_paranoid __read_mostly = 3; | |
404 | #else | |
405 | int sysctl_perf_event_paranoid __read_mostly = 1; | |
406 | #endif | |
0764771d | 407 | |
20443384 FW |
408 | /* Minimum for 512 kiB + 1 user control page */ |
409 | int sysctl_perf_event_mlock __read_mostly = 512 + (PAGE_SIZE / 1024); /* 'free' kiB per user */ | |
df58ab24 PZ |
410 | |
411 | /* | |
cdd6c482 | 412 | * max perf event sample rate |
df58ab24 | 413 | */ |
14c63f17 DH |
414 | #define DEFAULT_MAX_SAMPLE_RATE 100000 |
415 | #define DEFAULT_SAMPLE_PERIOD_NS (NSEC_PER_SEC / DEFAULT_MAX_SAMPLE_RATE) | |
416 | #define DEFAULT_CPU_TIME_MAX_PERCENT 25 | |
417 | ||
418 | int sysctl_perf_event_sample_rate __read_mostly = DEFAULT_MAX_SAMPLE_RATE; | |
419 | ||
420 | static int max_samples_per_tick __read_mostly = DIV_ROUND_UP(DEFAULT_MAX_SAMPLE_RATE, HZ); | |
421 | static int perf_sample_period_ns __read_mostly = DEFAULT_SAMPLE_PERIOD_NS; | |
422 | ||
d9494cb4 PZ |
423 | static int perf_sample_allowed_ns __read_mostly = |
424 | DEFAULT_SAMPLE_PERIOD_NS * DEFAULT_CPU_TIME_MAX_PERCENT / 100; | |
14c63f17 | 425 | |
18ab2cd3 | 426 | static void update_perf_cpu_limits(void) |
14c63f17 DH |
427 | { |
428 | u64 tmp = perf_sample_period_ns; | |
429 | ||
430 | tmp *= sysctl_perf_cpu_time_max_percent; | |
91a612ee PZ |
431 | tmp = div_u64(tmp, 100); |
432 | if (!tmp) | |
433 | tmp = 1; | |
434 | ||
435 | WRITE_ONCE(perf_sample_allowed_ns, tmp); | |
14c63f17 | 436 | } |
163ec435 | 437 | |
9e630205 SE |
438 | static int perf_rotate_context(struct perf_cpu_context *cpuctx); |
439 | ||
163ec435 PZ |
440 | int perf_proc_update_handler(struct ctl_table *table, int write, |
441 | void __user *buffer, size_t *lenp, | |
442 | loff_t *ppos) | |
443 | { | |
fdca8490 SE |
444 | int ret; |
445 | int perf_cpu = sysctl_perf_cpu_time_max_percent; | |
ab7fdefb KL |
446 | /* |
447 | * If throttling is disabled don't allow the write: | |
448 | */ | |
fdca8490 | 449 | if (write && (perf_cpu == 100 || perf_cpu == 0)) |
ab7fdefb KL |
450 | return -EINVAL; |
451 | ||
fdca8490 SE |
452 | ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
453 | if (ret || !write) | |
454 | return ret; | |
455 | ||
163ec435 | 456 | max_samples_per_tick = DIV_ROUND_UP(sysctl_perf_event_sample_rate, HZ); |
14c63f17 DH |
457 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; |
458 | update_perf_cpu_limits(); | |
459 | ||
460 | return 0; | |
461 | } | |
462 | ||
463 | int sysctl_perf_cpu_time_max_percent __read_mostly = DEFAULT_CPU_TIME_MAX_PERCENT; | |
464 | ||
465 | int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write, | |
466 | void __user *buffer, size_t *lenp, | |
467 | loff_t *ppos) | |
468 | { | |
1572e45a | 469 | int ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
14c63f17 DH |
470 | |
471 | if (ret || !write) | |
472 | return ret; | |
473 | ||
b303e7c1 PZ |
474 | if (sysctl_perf_cpu_time_max_percent == 100 || |
475 | sysctl_perf_cpu_time_max_percent == 0) { | |
91a612ee PZ |
476 | printk(KERN_WARNING |
477 | "perf: Dynamic interrupt throttling disabled, can hang your system!\n"); | |
478 | WRITE_ONCE(perf_sample_allowed_ns, 0); | |
479 | } else { | |
480 | update_perf_cpu_limits(); | |
481 | } | |
163ec435 PZ |
482 | |
483 | return 0; | |
484 | } | |
1ccd1549 | 485 | |
14c63f17 DH |
486 | /* |
487 | * perf samples are done in some very critical code paths (NMIs). | |
488 | * If they take too much CPU time, the system can lock up and not | |
489 | * get any real work done. This will drop the sample rate when | |
490 | * we detect that events are taking too long. | |
491 | */ | |
492 | #define NR_ACCUMULATED_SAMPLES 128 | |
d9494cb4 | 493 | static DEFINE_PER_CPU(u64, running_sample_length); |
14c63f17 | 494 | |
91a612ee PZ |
495 | static u64 __report_avg; |
496 | static u64 __report_allowed; | |
497 | ||
6a02ad66 | 498 | static void perf_duration_warn(struct irq_work *w) |
14c63f17 | 499 | { |
0d87d7ec | 500 | printk_ratelimited(KERN_INFO |
91a612ee PZ |
501 | "perf: interrupt took too long (%lld > %lld), lowering " |
502 | "kernel.perf_event_max_sample_rate to %d\n", | |
503 | __report_avg, __report_allowed, | |
504 | sysctl_perf_event_sample_rate); | |
6a02ad66 PZ |
505 | } |
506 | ||
507 | static DEFINE_IRQ_WORK(perf_duration_work, perf_duration_warn); | |
508 | ||
509 | void perf_sample_event_took(u64 sample_len_ns) | |
510 | { | |
91a612ee PZ |
511 | u64 max_len = READ_ONCE(perf_sample_allowed_ns); |
512 | u64 running_len; | |
513 | u64 avg_len; | |
514 | u32 max; | |
14c63f17 | 515 | |
91a612ee | 516 | if (max_len == 0) |
14c63f17 DH |
517 | return; |
518 | ||
91a612ee PZ |
519 | /* Decay the counter by 1 average sample. */ |
520 | running_len = __this_cpu_read(running_sample_length); | |
521 | running_len -= running_len/NR_ACCUMULATED_SAMPLES; | |
522 | running_len += sample_len_ns; | |
523 | __this_cpu_write(running_sample_length, running_len); | |
14c63f17 DH |
524 | |
525 | /* | |
91a612ee PZ |
526 | * Note: this will be biased artifically low until we have |
527 | * seen NR_ACCUMULATED_SAMPLES. Doing it this way keeps us | |
14c63f17 DH |
528 | * from having to maintain a count. |
529 | */ | |
91a612ee PZ |
530 | avg_len = running_len/NR_ACCUMULATED_SAMPLES; |
531 | if (avg_len <= max_len) | |
14c63f17 DH |
532 | return; |
533 | ||
91a612ee PZ |
534 | __report_avg = avg_len; |
535 | __report_allowed = max_len; | |
14c63f17 | 536 | |
91a612ee PZ |
537 | /* |
538 | * Compute a throttle threshold 25% below the current duration. | |
539 | */ | |
540 | avg_len += avg_len / 4; | |
541 | max = (TICK_NSEC / 100) * sysctl_perf_cpu_time_max_percent; | |
542 | if (avg_len < max) | |
543 | max /= (u32)avg_len; | |
544 | else | |
545 | max = 1; | |
14c63f17 | 546 | |
91a612ee PZ |
547 | WRITE_ONCE(perf_sample_allowed_ns, avg_len); |
548 | WRITE_ONCE(max_samples_per_tick, max); | |
549 | ||
550 | sysctl_perf_event_sample_rate = max * HZ; | |
551 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; | |
6a02ad66 | 552 | |
cd578abb | 553 | if (!irq_work_queue(&perf_duration_work)) { |
91a612ee | 554 | early_printk("perf: interrupt took too long (%lld > %lld), lowering " |
cd578abb | 555 | "kernel.perf_event_max_sample_rate to %d\n", |
91a612ee | 556 | __report_avg, __report_allowed, |
cd578abb PZ |
557 | sysctl_perf_event_sample_rate); |
558 | } | |
14c63f17 DH |
559 | } |
560 | ||
cdd6c482 | 561 | static atomic64_t perf_event_id; |
a96bbc16 | 562 | |
0b3fcf17 SE |
563 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, |
564 | enum event_type_t event_type); | |
565 | ||
566 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
567 | enum event_type_t event_type, |
568 | struct task_struct *task); | |
569 | ||
570 | static void update_context_time(struct perf_event_context *ctx); | |
571 | static u64 perf_event_time(struct perf_event *event); | |
0b3fcf17 | 572 | |
cdd6c482 | 573 | void __weak perf_event_print_debug(void) { } |
0793a61d | 574 | |
84c79910 | 575 | extern __weak const char *perf_pmu_name(void) |
0793a61d | 576 | { |
84c79910 | 577 | return "pmu"; |
0793a61d TG |
578 | } |
579 | ||
0b3fcf17 SE |
580 | static inline u64 perf_clock(void) |
581 | { | |
582 | return local_clock(); | |
583 | } | |
584 | ||
34f43927 PZ |
585 | static inline u64 perf_event_clock(struct perf_event *event) |
586 | { | |
587 | return event->clock(); | |
588 | } | |
589 | ||
0d3d73aa PZ |
590 | /* |
591 | * State based event timekeeping... | |
592 | * | |
593 | * The basic idea is to use event->state to determine which (if any) time | |
594 | * fields to increment with the current delta. This means we only need to | |
595 | * update timestamps when we change state or when they are explicitly requested | |
596 | * (read). | |
597 | * | |
598 | * Event groups make things a little more complicated, but not terribly so. The | |
599 | * rules for a group are that if the group leader is OFF the entire group is | |
600 | * OFF, irrespecive of what the group member states are. This results in | |
601 | * __perf_effective_state(). | |
602 | * | |
603 | * A futher ramification is that when a group leader flips between OFF and | |
604 | * !OFF, we need to update all group member times. | |
605 | * | |
606 | * | |
607 | * NOTE: perf_event_time() is based on the (cgroup) context time, and thus we | |
608 | * need to make sure the relevant context time is updated before we try and | |
609 | * update our timestamps. | |
610 | */ | |
611 | ||
612 | static __always_inline enum perf_event_state | |
613 | __perf_effective_state(struct perf_event *event) | |
614 | { | |
615 | struct perf_event *leader = event->group_leader; | |
616 | ||
617 | if (leader->state <= PERF_EVENT_STATE_OFF) | |
618 | return leader->state; | |
619 | ||
620 | return event->state; | |
621 | } | |
622 | ||
623 | static __always_inline void | |
624 | __perf_update_times(struct perf_event *event, u64 now, u64 *enabled, u64 *running) | |
625 | { | |
626 | enum perf_event_state state = __perf_effective_state(event); | |
627 | u64 delta = now - event->tstamp; | |
628 | ||
629 | *enabled = event->total_time_enabled; | |
630 | if (state >= PERF_EVENT_STATE_INACTIVE) | |
631 | *enabled += delta; | |
632 | ||
633 | *running = event->total_time_running; | |
634 | if (state >= PERF_EVENT_STATE_ACTIVE) | |
635 | *running += delta; | |
636 | } | |
637 | ||
638 | static void perf_event_update_time(struct perf_event *event) | |
639 | { | |
640 | u64 now = perf_event_time(event); | |
641 | ||
642 | __perf_update_times(event, now, &event->total_time_enabled, | |
643 | &event->total_time_running); | |
644 | event->tstamp = now; | |
645 | } | |
646 | ||
647 | static void perf_event_update_sibling_time(struct perf_event *leader) | |
648 | { | |
649 | struct perf_event *sibling; | |
650 | ||
651 | list_for_each_entry(sibling, &leader->sibling_list, group_entry) | |
652 | perf_event_update_time(sibling); | |
653 | } | |
654 | ||
655 | static void | |
656 | perf_event_set_state(struct perf_event *event, enum perf_event_state state) | |
657 | { | |
658 | if (event->state == state) | |
659 | return; | |
660 | ||
661 | perf_event_update_time(event); | |
662 | /* | |
663 | * If a group leader gets enabled/disabled all its siblings | |
664 | * are affected too. | |
665 | */ | |
666 | if ((event->state < 0) ^ (state < 0)) | |
667 | perf_event_update_sibling_time(event); | |
668 | ||
669 | WRITE_ONCE(event->state, state); | |
670 | } | |
671 | ||
e5d1367f SE |
672 | #ifdef CONFIG_CGROUP_PERF |
673 | ||
e5d1367f SE |
674 | static inline bool |
675 | perf_cgroup_match(struct perf_event *event) | |
676 | { | |
677 | struct perf_event_context *ctx = event->ctx; | |
678 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
679 | ||
ef824fa1 TH |
680 | /* @event doesn't care about cgroup */ |
681 | if (!event->cgrp) | |
682 | return true; | |
683 | ||
684 | /* wants specific cgroup scope but @cpuctx isn't associated with any */ | |
685 | if (!cpuctx->cgrp) | |
686 | return false; | |
687 | ||
688 | /* | |
689 | * Cgroup scoping is recursive. An event enabled for a cgroup is | |
690 | * also enabled for all its descendant cgroups. If @cpuctx's | |
691 | * cgroup is a descendant of @event's (the test covers identity | |
692 | * case), it's a match. | |
693 | */ | |
694 | return cgroup_is_descendant(cpuctx->cgrp->css.cgroup, | |
695 | event->cgrp->css.cgroup); | |
e5d1367f SE |
696 | } |
697 | ||
e5d1367f SE |
698 | static inline void perf_detach_cgroup(struct perf_event *event) |
699 | { | |
4e2ba650 | 700 | css_put(&event->cgrp->css); |
e5d1367f SE |
701 | event->cgrp = NULL; |
702 | } | |
703 | ||
704 | static inline int is_cgroup_event(struct perf_event *event) | |
705 | { | |
706 | return event->cgrp != NULL; | |
707 | } | |
708 | ||
709 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
710 | { | |
711 | struct perf_cgroup_info *t; | |
712 | ||
713 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
714 | return t->time; | |
715 | } | |
716 | ||
717 | static inline void __update_cgrp_time(struct perf_cgroup *cgrp) | |
718 | { | |
719 | struct perf_cgroup_info *info; | |
720 | u64 now; | |
721 | ||
722 | now = perf_clock(); | |
723 | ||
724 | info = this_cpu_ptr(cgrp->info); | |
725 | ||
726 | info->time += now - info->timestamp; | |
727 | info->timestamp = now; | |
728 | } | |
729 | ||
730 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
731 | { | |
c482b758 SL |
732 | struct perf_cgroup *cgrp = cpuctx->cgrp; |
733 | struct cgroup_subsys_state *css; | |
734 | ||
735 | if (cgrp) { | |
736 | for (css = &cgrp->css; css; css = css->parent) { | |
737 | cgrp = container_of(css, struct perf_cgroup, css); | |
738 | __update_cgrp_time(cgrp); | |
739 | } | |
740 | } | |
e5d1367f SE |
741 | } |
742 | ||
743 | static inline void update_cgrp_time_from_event(struct perf_event *event) | |
744 | { | |
3f7cce3c SE |
745 | struct perf_cgroup *cgrp; |
746 | ||
e5d1367f | 747 | /* |
3f7cce3c SE |
748 | * ensure we access cgroup data only when needed and |
749 | * when we know the cgroup is pinned (css_get) | |
e5d1367f | 750 | */ |
3f7cce3c | 751 | if (!is_cgroup_event(event)) |
e5d1367f SE |
752 | return; |
753 | ||
614e4c4e | 754 | cgrp = perf_cgroup_from_task(current, event->ctx); |
3f7cce3c SE |
755 | /* |
756 | * Do not update time when cgroup is not active | |
757 | */ | |
e6a52033 | 758 | if (cgroup_is_descendant(cgrp->css.cgroup, event->cgrp->css.cgroup)) |
3f7cce3c | 759 | __update_cgrp_time(event->cgrp); |
e5d1367f SE |
760 | } |
761 | ||
762 | static inline void | |
3f7cce3c SE |
763 | perf_cgroup_set_timestamp(struct task_struct *task, |
764 | struct perf_event_context *ctx) | |
e5d1367f SE |
765 | { |
766 | struct perf_cgroup *cgrp; | |
767 | struct perf_cgroup_info *info; | |
c482b758 | 768 | struct cgroup_subsys_state *css; |
e5d1367f | 769 | |
3f7cce3c SE |
770 | /* |
771 | * ctx->lock held by caller | |
772 | * ensure we do not access cgroup data | |
773 | * unless we have the cgroup pinned (css_get) | |
774 | */ | |
775 | if (!task || !ctx->nr_cgroups) | |
e5d1367f SE |
776 | return; |
777 | ||
614e4c4e | 778 | cgrp = perf_cgroup_from_task(task, ctx); |
c482b758 SL |
779 | |
780 | for (css = &cgrp->css; css; css = css->parent) { | |
781 | cgrp = container_of(css, struct perf_cgroup, css); | |
782 | info = this_cpu_ptr(cgrp->info); | |
783 | info->timestamp = ctx->timestamp; | |
784 | } | |
e5d1367f SE |
785 | } |
786 | ||
058fe1c0 DCC |
787 | static DEFINE_PER_CPU(struct list_head, cgrp_cpuctx_list); |
788 | ||
e5d1367f SE |
789 | #define PERF_CGROUP_SWOUT 0x1 /* cgroup switch out every event */ |
790 | #define PERF_CGROUP_SWIN 0x2 /* cgroup switch in events based on task */ | |
791 | ||
792 | /* | |
793 | * reschedule events based on the cgroup constraint of task. | |
794 | * | |
795 | * mode SWOUT : schedule out everything | |
796 | * mode SWIN : schedule in based on cgroup for next | |
797 | */ | |
18ab2cd3 | 798 | static void perf_cgroup_switch(struct task_struct *task, int mode) |
e5d1367f SE |
799 | { |
800 | struct perf_cpu_context *cpuctx; | |
058fe1c0 | 801 | struct list_head *list; |
e5d1367f SE |
802 | unsigned long flags; |
803 | ||
804 | /* | |
058fe1c0 DCC |
805 | * Disable interrupts and preemption to avoid this CPU's |
806 | * cgrp_cpuctx_entry to change under us. | |
e5d1367f SE |
807 | */ |
808 | local_irq_save(flags); | |
809 | ||
058fe1c0 DCC |
810 | list = this_cpu_ptr(&cgrp_cpuctx_list); |
811 | list_for_each_entry(cpuctx, list, cgrp_cpuctx_entry) { | |
812 | WARN_ON_ONCE(cpuctx->ctx.nr_cgroups == 0); | |
e5d1367f | 813 | |
058fe1c0 DCC |
814 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
815 | perf_pmu_disable(cpuctx->ctx.pmu); | |
e5d1367f | 816 | |
058fe1c0 DCC |
817 | if (mode & PERF_CGROUP_SWOUT) { |
818 | cpu_ctx_sched_out(cpuctx, EVENT_ALL); | |
819 | /* | |
820 | * must not be done before ctxswout due | |
821 | * to event_filter_match() in event_sched_out() | |
822 | */ | |
823 | cpuctx->cgrp = NULL; | |
824 | } | |
e5d1367f | 825 | |
058fe1c0 DCC |
826 | if (mode & PERF_CGROUP_SWIN) { |
827 | WARN_ON_ONCE(cpuctx->cgrp); | |
828 | /* | |
829 | * set cgrp before ctxsw in to allow | |
830 | * event_filter_match() to not have to pass | |
831 | * task around | |
832 | * we pass the cpuctx->ctx to perf_cgroup_from_task() | |
833 | * because cgorup events are only per-cpu | |
834 | */ | |
835 | cpuctx->cgrp = perf_cgroup_from_task(task, | |
836 | &cpuctx->ctx); | |
837 | cpu_ctx_sched_in(cpuctx, EVENT_ALL, task); | |
e5d1367f | 838 | } |
058fe1c0 DCC |
839 | perf_pmu_enable(cpuctx->ctx.pmu); |
840 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
e5d1367f SE |
841 | } |
842 | ||
e5d1367f SE |
843 | local_irq_restore(flags); |
844 | } | |
845 | ||
a8d757ef SE |
846 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
847 | struct task_struct *next) | |
e5d1367f | 848 | { |
a8d757ef SE |
849 | struct perf_cgroup *cgrp1; |
850 | struct perf_cgroup *cgrp2 = NULL; | |
851 | ||
ddaaf4e2 | 852 | rcu_read_lock(); |
a8d757ef SE |
853 | /* |
854 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
855 | * we do not need to pass the ctx here because we know |
856 | * we are holding the rcu lock | |
a8d757ef | 857 | */ |
614e4c4e | 858 | cgrp1 = perf_cgroup_from_task(task, NULL); |
70a01657 | 859 | cgrp2 = perf_cgroup_from_task(next, NULL); |
a8d757ef SE |
860 | |
861 | /* | |
862 | * only schedule out current cgroup events if we know | |
863 | * that we are switching to a different cgroup. Otherwise, | |
864 | * do no touch the cgroup events. | |
865 | */ | |
866 | if (cgrp1 != cgrp2) | |
867 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT); | |
ddaaf4e2 SE |
868 | |
869 | rcu_read_unlock(); | |
e5d1367f SE |
870 | } |
871 | ||
a8d757ef SE |
872 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
873 | struct task_struct *task) | |
e5d1367f | 874 | { |
a8d757ef SE |
875 | struct perf_cgroup *cgrp1; |
876 | struct perf_cgroup *cgrp2 = NULL; | |
877 | ||
ddaaf4e2 | 878 | rcu_read_lock(); |
a8d757ef SE |
879 | /* |
880 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
881 | * we do not need to pass the ctx here because we know |
882 | * we are holding the rcu lock | |
a8d757ef | 883 | */ |
614e4c4e | 884 | cgrp1 = perf_cgroup_from_task(task, NULL); |
614e4c4e | 885 | cgrp2 = perf_cgroup_from_task(prev, NULL); |
a8d757ef SE |
886 | |
887 | /* | |
888 | * only need to schedule in cgroup events if we are changing | |
889 | * cgroup during ctxsw. Cgroup events were not scheduled | |
890 | * out of ctxsw out if that was not the case. | |
891 | */ | |
892 | if (cgrp1 != cgrp2) | |
893 | perf_cgroup_switch(task, PERF_CGROUP_SWIN); | |
ddaaf4e2 SE |
894 | |
895 | rcu_read_unlock(); | |
e5d1367f SE |
896 | } |
897 | ||
898 | static inline int perf_cgroup_connect(int fd, struct perf_event *event, | |
899 | struct perf_event_attr *attr, | |
900 | struct perf_event *group_leader) | |
901 | { | |
902 | struct perf_cgroup *cgrp; | |
903 | struct cgroup_subsys_state *css; | |
2903ff01 AV |
904 | struct fd f = fdget(fd); |
905 | int ret = 0; | |
e5d1367f | 906 | |
2903ff01 | 907 | if (!f.file) |
e5d1367f SE |
908 | return -EBADF; |
909 | ||
b583043e | 910 | css = css_tryget_online_from_dir(f.file->f_path.dentry, |
ec903c0c | 911 | &perf_event_cgrp_subsys); |
3db272c0 LZ |
912 | if (IS_ERR(css)) { |
913 | ret = PTR_ERR(css); | |
914 | goto out; | |
915 | } | |
e5d1367f SE |
916 | |
917 | cgrp = container_of(css, struct perf_cgroup, css); | |
918 | event->cgrp = cgrp; | |
919 | ||
920 | /* | |
921 | * all events in a group must monitor | |
922 | * the same cgroup because a task belongs | |
923 | * to only one perf cgroup at a time | |
924 | */ | |
925 | if (group_leader && group_leader->cgrp != cgrp) { | |
926 | perf_detach_cgroup(event); | |
927 | ret = -EINVAL; | |
e5d1367f | 928 | } |
3db272c0 | 929 | out: |
2903ff01 | 930 | fdput(f); |
e5d1367f SE |
931 | return ret; |
932 | } | |
933 | ||
934 | static inline void | |
935 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
936 | { | |
937 | struct perf_cgroup_info *t; | |
938 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
939 | event->shadow_ctx_time = now - t->timestamp; | |
940 | } | |
941 | ||
db4a8356 DCC |
942 | /* |
943 | * Update cpuctx->cgrp so that it is set when first cgroup event is added and | |
944 | * cleared when last cgroup event is removed. | |
945 | */ | |
946 | static inline void | |
947 | list_update_cgroup_event(struct perf_event *event, | |
948 | struct perf_event_context *ctx, bool add) | |
949 | { | |
950 | struct perf_cpu_context *cpuctx; | |
058fe1c0 | 951 | struct list_head *cpuctx_entry; |
db4a8356 DCC |
952 | |
953 | if (!is_cgroup_event(event)) | |
954 | return; | |
955 | ||
db4a8356 DCC |
956 | /* |
957 | * Because cgroup events are always per-cpu events, | |
958 | * this will always be called from the right CPU. | |
959 | */ | |
960 | cpuctx = __get_cpu_context(ctx); | |
fcb3f8a6 | 961 | |
962 | /* | |
963 | * Since setting cpuctx->cgrp is conditional on the current @cgrp | |
964 | * matching the event's cgroup, we must do this for every new event, | |
965 | * because if the first would mismatch, the second would not try again | |
966 | * and we would leave cpuctx->cgrp unset. | |
967 | */ | |
968 | if (add && !cpuctx->cgrp) { | |
be96b316 TH |
969 | struct perf_cgroup *cgrp = perf_cgroup_from_task(current, ctx); |
970 | ||
be96b316 TH |
971 | if (cgroup_is_descendant(cgrp->css.cgroup, event->cgrp->css.cgroup)) |
972 | cpuctx->cgrp = cgrp; | |
058fe1c0 | 973 | } |
fcb3f8a6 | 974 | |
975 | if (add && ctx->nr_cgroups++) | |
976 | return; | |
977 | else if (!add && --ctx->nr_cgroups) | |
978 | return; | |
979 | ||
980 | /* no cgroup running */ | |
981 | if (!add) | |
982 | cpuctx->cgrp = NULL; | |
983 | ||
984 | cpuctx_entry = &cpuctx->cgrp_cpuctx_entry; | |
985 | if (add) | |
986 | list_add(cpuctx_entry, this_cpu_ptr(&cgrp_cpuctx_list)); | |
987 | else | |
988 | list_del(cpuctx_entry); | |
db4a8356 DCC |
989 | } |
990 | ||
e5d1367f SE |
991 | #else /* !CONFIG_CGROUP_PERF */ |
992 | ||
993 | static inline bool | |
994 | perf_cgroup_match(struct perf_event *event) | |
995 | { | |
996 | return true; | |
997 | } | |
998 | ||
999 | static inline void perf_detach_cgroup(struct perf_event *event) | |
1000 | {} | |
1001 | ||
1002 | static inline int is_cgroup_event(struct perf_event *event) | |
1003 | { | |
1004 | return 0; | |
1005 | } | |
1006 | ||
e5d1367f SE |
1007 | static inline void update_cgrp_time_from_event(struct perf_event *event) |
1008 | { | |
1009 | } | |
1010 | ||
1011 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
1012 | { | |
1013 | } | |
1014 | ||
a8d757ef SE |
1015 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
1016 | struct task_struct *next) | |
e5d1367f SE |
1017 | { |
1018 | } | |
1019 | ||
a8d757ef SE |
1020 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
1021 | struct task_struct *task) | |
e5d1367f SE |
1022 | { |
1023 | } | |
1024 | ||
1025 | static inline int perf_cgroup_connect(pid_t pid, struct perf_event *event, | |
1026 | struct perf_event_attr *attr, | |
1027 | struct perf_event *group_leader) | |
1028 | { | |
1029 | return -EINVAL; | |
1030 | } | |
1031 | ||
1032 | static inline void | |
3f7cce3c SE |
1033 | perf_cgroup_set_timestamp(struct task_struct *task, |
1034 | struct perf_event_context *ctx) | |
e5d1367f SE |
1035 | { |
1036 | } | |
1037 | ||
1038 | void | |
1039 | perf_cgroup_switch(struct task_struct *task, struct task_struct *next) | |
1040 | { | |
1041 | } | |
1042 | ||
1043 | static inline void | |
1044 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
1045 | { | |
1046 | } | |
1047 | ||
1048 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
1049 | { | |
1050 | return 0; | |
1051 | } | |
1052 | ||
db4a8356 DCC |
1053 | static inline void |
1054 | list_update_cgroup_event(struct perf_event *event, | |
1055 | struct perf_event_context *ctx, bool add) | |
1056 | { | |
1057 | } | |
1058 | ||
e5d1367f SE |
1059 | #endif |
1060 | ||
9e630205 SE |
1061 | /* |
1062 | * set default to be dependent on timer tick just | |
1063 | * like original code | |
1064 | */ | |
1065 | #define PERF_CPU_HRTIMER (1000 / HZ) | |
1066 | /* | |
8a1115ff | 1067 | * function must be called with interrupts disabled |
9e630205 | 1068 | */ |
272325c4 | 1069 | static enum hrtimer_restart perf_mux_hrtimer_handler(struct hrtimer *hr) |
9e630205 SE |
1070 | { |
1071 | struct perf_cpu_context *cpuctx; | |
9e630205 SE |
1072 | int rotations = 0; |
1073 | ||
16444645 | 1074 | lockdep_assert_irqs_disabled(); |
9e630205 SE |
1075 | |
1076 | cpuctx = container_of(hr, struct perf_cpu_context, hrtimer); | |
9e630205 SE |
1077 | rotations = perf_rotate_context(cpuctx); |
1078 | ||
4cfafd30 PZ |
1079 | raw_spin_lock(&cpuctx->hrtimer_lock); |
1080 | if (rotations) | |
9e630205 | 1081 | hrtimer_forward_now(hr, cpuctx->hrtimer_interval); |
4cfafd30 PZ |
1082 | else |
1083 | cpuctx->hrtimer_active = 0; | |
1084 | raw_spin_unlock(&cpuctx->hrtimer_lock); | |
9e630205 | 1085 | |
4cfafd30 | 1086 | return rotations ? HRTIMER_RESTART : HRTIMER_NORESTART; |
9e630205 SE |
1087 | } |
1088 | ||
272325c4 | 1089 | static void __perf_mux_hrtimer_init(struct perf_cpu_context *cpuctx, int cpu) |
9e630205 | 1090 | { |
272325c4 | 1091 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1092 | struct pmu *pmu = cpuctx->ctx.pmu; |
272325c4 | 1093 | u64 interval; |
9e630205 SE |
1094 | |
1095 | /* no multiplexing needed for SW PMU */ | |
1096 | if (pmu->task_ctx_nr == perf_sw_context) | |
1097 | return; | |
1098 | ||
62b85639 SE |
1099 | /* |
1100 | * check default is sane, if not set then force to | |
1101 | * default interval (1/tick) | |
1102 | */ | |
272325c4 PZ |
1103 | interval = pmu->hrtimer_interval_ms; |
1104 | if (interval < 1) | |
1105 | interval = pmu->hrtimer_interval_ms = PERF_CPU_HRTIMER; | |
62b85639 | 1106 | |
272325c4 | 1107 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * interval); |
9e630205 | 1108 | |
4cfafd30 PZ |
1109 | raw_spin_lock_init(&cpuctx->hrtimer_lock); |
1110 | hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_PINNED); | |
272325c4 | 1111 | timer->function = perf_mux_hrtimer_handler; |
9e630205 SE |
1112 | } |
1113 | ||
272325c4 | 1114 | static int perf_mux_hrtimer_restart(struct perf_cpu_context *cpuctx) |
9e630205 | 1115 | { |
272325c4 | 1116 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1117 | struct pmu *pmu = cpuctx->ctx.pmu; |
4cfafd30 | 1118 | unsigned long flags; |
9e630205 SE |
1119 | |
1120 | /* not for SW PMU */ | |
1121 | if (pmu->task_ctx_nr == perf_sw_context) | |
272325c4 | 1122 | return 0; |
9e630205 | 1123 | |
4cfafd30 PZ |
1124 | raw_spin_lock_irqsave(&cpuctx->hrtimer_lock, flags); |
1125 | if (!cpuctx->hrtimer_active) { | |
1126 | cpuctx->hrtimer_active = 1; | |
1127 | hrtimer_forward_now(timer, cpuctx->hrtimer_interval); | |
1128 | hrtimer_start_expires(timer, HRTIMER_MODE_ABS_PINNED); | |
1129 | } | |
1130 | raw_spin_unlock_irqrestore(&cpuctx->hrtimer_lock, flags); | |
9e630205 | 1131 | |
272325c4 | 1132 | return 0; |
9e630205 SE |
1133 | } |
1134 | ||
33696fc0 | 1135 | void perf_pmu_disable(struct pmu *pmu) |
9e35ad38 | 1136 | { |
33696fc0 PZ |
1137 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1138 | if (!(*count)++) | |
1139 | pmu->pmu_disable(pmu); | |
9e35ad38 | 1140 | } |
9e35ad38 | 1141 | |
33696fc0 | 1142 | void perf_pmu_enable(struct pmu *pmu) |
9e35ad38 | 1143 | { |
33696fc0 PZ |
1144 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1145 | if (!--(*count)) | |
1146 | pmu->pmu_enable(pmu); | |
9e35ad38 | 1147 | } |
9e35ad38 | 1148 | |
2fde4f94 | 1149 | static DEFINE_PER_CPU(struct list_head, active_ctx_list); |
e9d2b064 PZ |
1150 | |
1151 | /* | |
2fde4f94 MR |
1152 | * perf_event_ctx_activate(), perf_event_ctx_deactivate(), and |
1153 | * perf_event_task_tick() are fully serialized because they're strictly cpu | |
1154 | * affine and perf_event_ctx{activate,deactivate} are called with IRQs | |
1155 | * disabled, while perf_event_task_tick is called from IRQ context. | |
e9d2b064 | 1156 | */ |
2fde4f94 | 1157 | static void perf_event_ctx_activate(struct perf_event_context *ctx) |
9e35ad38 | 1158 | { |
2fde4f94 | 1159 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
b5ab4cd5 | 1160 | |
16444645 | 1161 | lockdep_assert_irqs_disabled(); |
b5ab4cd5 | 1162 | |
2fde4f94 MR |
1163 | WARN_ON(!list_empty(&ctx->active_ctx_list)); |
1164 | ||
1165 | list_add(&ctx->active_ctx_list, head); | |
1166 | } | |
1167 | ||
1168 | static void perf_event_ctx_deactivate(struct perf_event_context *ctx) | |
1169 | { | |
16444645 | 1170 | lockdep_assert_irqs_disabled(); |
2fde4f94 MR |
1171 | |
1172 | WARN_ON(list_empty(&ctx->active_ctx_list)); | |
1173 | ||
1174 | list_del_init(&ctx->active_ctx_list); | |
9e35ad38 | 1175 | } |
9e35ad38 | 1176 | |
cdd6c482 | 1177 | static void get_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1178 | { |
e5289d4a | 1179 | WARN_ON(!atomic_inc_not_zero(&ctx->refcount)); |
a63eaf34 PM |
1180 | } |
1181 | ||
4af57ef2 YZ |
1182 | static void free_ctx(struct rcu_head *head) |
1183 | { | |
1184 | struct perf_event_context *ctx; | |
1185 | ||
1186 | ctx = container_of(head, struct perf_event_context, rcu_head); | |
1187 | kfree(ctx->task_ctx_data); | |
1188 | kfree(ctx); | |
1189 | } | |
1190 | ||
cdd6c482 | 1191 | static void put_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1192 | { |
564c2b21 PM |
1193 | if (atomic_dec_and_test(&ctx->refcount)) { |
1194 | if (ctx->parent_ctx) | |
1195 | put_ctx(ctx->parent_ctx); | |
63b6da39 | 1196 | if (ctx->task && ctx->task != TASK_TOMBSTONE) |
c93f7669 | 1197 | put_task_struct(ctx->task); |
4af57ef2 | 1198 | call_rcu(&ctx->rcu_head, free_ctx); |
564c2b21 | 1199 | } |
a63eaf34 PM |
1200 | } |
1201 | ||
f63a8daa PZ |
1202 | /* |
1203 | * Because of perf_event::ctx migration in sys_perf_event_open::move_group and | |
1204 | * perf_pmu_migrate_context() we need some magic. | |
1205 | * | |
1206 | * Those places that change perf_event::ctx will hold both | |
1207 | * perf_event_ctx::mutex of the 'old' and 'new' ctx value. | |
1208 | * | |
8b10c5e2 PZ |
1209 | * Lock ordering is by mutex address. There are two other sites where |
1210 | * perf_event_context::mutex nests and those are: | |
1211 | * | |
1212 | * - perf_event_exit_task_context() [ child , 0 ] | |
8ba289b8 PZ |
1213 | * perf_event_exit_event() |
1214 | * put_event() [ parent, 1 ] | |
8b10c5e2 PZ |
1215 | * |
1216 | * - perf_event_init_context() [ parent, 0 ] | |
1217 | * inherit_task_group() | |
1218 | * inherit_group() | |
1219 | * inherit_event() | |
1220 | * perf_event_alloc() | |
1221 | * perf_init_event() | |
1222 | * perf_try_init_event() [ child , 1 ] | |
1223 | * | |
1224 | * While it appears there is an obvious deadlock here -- the parent and child | |
1225 | * nesting levels are inverted between the two. This is in fact safe because | |
1226 | * life-time rules separate them. That is an exiting task cannot fork, and a | |
1227 | * spawning task cannot (yet) exit. | |
1228 | * | |
1229 | * But remember that that these are parent<->child context relations, and | |
1230 | * migration does not affect children, therefore these two orderings should not | |
1231 | * interact. | |
f63a8daa PZ |
1232 | * |
1233 | * The change in perf_event::ctx does not affect children (as claimed above) | |
1234 | * because the sys_perf_event_open() case will install a new event and break | |
1235 | * the ctx parent<->child relation, and perf_pmu_migrate_context() is only | |
1236 | * concerned with cpuctx and that doesn't have children. | |
1237 | * | |
1238 | * The places that change perf_event::ctx will issue: | |
1239 | * | |
1240 | * perf_remove_from_context(); | |
1241 | * synchronize_rcu(); | |
1242 | * perf_install_in_context(); | |
1243 | * | |
1244 | * to affect the change. The remove_from_context() + synchronize_rcu() should | |
1245 | * quiesce the event, after which we can install it in the new location. This | |
1246 | * means that only external vectors (perf_fops, prctl) can perturb the event | |
1247 | * while in transit. Therefore all such accessors should also acquire | |
1248 | * perf_event_context::mutex to serialize against this. | |
1249 | * | |
1250 | * However; because event->ctx can change while we're waiting to acquire | |
1251 | * ctx->mutex we must be careful and use the below perf_event_ctx_lock() | |
1252 | * function. | |
1253 | * | |
1254 | * Lock order: | |
79c9ce57 | 1255 | * cred_guard_mutex |
f63a8daa PZ |
1256 | * task_struct::perf_event_mutex |
1257 | * perf_event_context::mutex | |
f63a8daa | 1258 | * perf_event::child_mutex; |
07c4a776 | 1259 | * perf_event_context::lock |
f63a8daa PZ |
1260 | * perf_event::mmap_mutex |
1261 | * mmap_sem | |
d2f9c5e7 | 1262 | * perf_addr_filters_head::lock |
82d94856 PZ |
1263 | * |
1264 | * cpu_hotplug_lock | |
1265 | * pmus_lock | |
1266 | * cpuctx->mutex / perf_event_context::mutex | |
f63a8daa | 1267 | */ |
a83fe28e PZ |
1268 | static struct perf_event_context * |
1269 | perf_event_ctx_lock_nested(struct perf_event *event, int nesting) | |
f63a8daa PZ |
1270 | { |
1271 | struct perf_event_context *ctx; | |
1272 | ||
1273 | again: | |
1274 | rcu_read_lock(); | |
6aa7de05 | 1275 | ctx = READ_ONCE(event->ctx); |
f63a8daa PZ |
1276 | if (!atomic_inc_not_zero(&ctx->refcount)) { |
1277 | rcu_read_unlock(); | |
1278 | goto again; | |
1279 | } | |
1280 | rcu_read_unlock(); | |
1281 | ||
a83fe28e | 1282 | mutex_lock_nested(&ctx->mutex, nesting); |
f63a8daa PZ |
1283 | if (event->ctx != ctx) { |
1284 | mutex_unlock(&ctx->mutex); | |
1285 | put_ctx(ctx); | |
1286 | goto again; | |
1287 | } | |
1288 | ||
1289 | return ctx; | |
1290 | } | |
1291 | ||
a83fe28e PZ |
1292 | static inline struct perf_event_context * |
1293 | perf_event_ctx_lock(struct perf_event *event) | |
1294 | { | |
1295 | return perf_event_ctx_lock_nested(event, 0); | |
1296 | } | |
1297 | ||
f63a8daa PZ |
1298 | static void perf_event_ctx_unlock(struct perf_event *event, |
1299 | struct perf_event_context *ctx) | |
1300 | { | |
1301 | mutex_unlock(&ctx->mutex); | |
1302 | put_ctx(ctx); | |
1303 | } | |
1304 | ||
211de6eb PZ |
1305 | /* |
1306 | * This must be done under the ctx->lock, such as to serialize against | |
1307 | * context_equiv(), therefore we cannot call put_ctx() since that might end up | |
1308 | * calling scheduler related locks and ctx->lock nests inside those. | |
1309 | */ | |
1310 | static __must_check struct perf_event_context * | |
1311 | unclone_ctx(struct perf_event_context *ctx) | |
71a851b4 | 1312 | { |
211de6eb PZ |
1313 | struct perf_event_context *parent_ctx = ctx->parent_ctx; |
1314 | ||
1315 | lockdep_assert_held(&ctx->lock); | |
1316 | ||
1317 | if (parent_ctx) | |
71a851b4 | 1318 | ctx->parent_ctx = NULL; |
5a3126d4 | 1319 | ctx->generation++; |
211de6eb PZ |
1320 | |
1321 | return parent_ctx; | |
71a851b4 PZ |
1322 | } |
1323 | ||
1d953111 ON |
1324 | static u32 perf_event_pid_type(struct perf_event *event, struct task_struct *p, |
1325 | enum pid_type type) | |
6844c09d | 1326 | { |
1d953111 | 1327 | u32 nr; |
6844c09d ACM |
1328 | /* |
1329 | * only top level events have the pid namespace they were created in | |
1330 | */ | |
1331 | if (event->parent) | |
1332 | event = event->parent; | |
1333 | ||
1d953111 ON |
1334 | nr = __task_pid_nr_ns(p, type, event->ns); |
1335 | /* avoid -1 if it is idle thread or runs in another ns */ | |
1336 | if (!nr && !pid_alive(p)) | |
1337 | nr = -1; | |
1338 | return nr; | |
6844c09d ACM |
1339 | } |
1340 | ||
1d953111 | 1341 | static u32 perf_event_pid(struct perf_event *event, struct task_struct *p) |
6844c09d | 1342 | { |
1d953111 ON |
1343 | return perf_event_pid_type(event, p, __PIDTYPE_TGID); |
1344 | } | |
6844c09d | 1345 | |
1d953111 ON |
1346 | static u32 perf_event_tid(struct perf_event *event, struct task_struct *p) |
1347 | { | |
1348 | return perf_event_pid_type(event, p, PIDTYPE_PID); | |
6844c09d ACM |
1349 | } |
1350 | ||
7f453c24 | 1351 | /* |
cdd6c482 | 1352 | * If we inherit events we want to return the parent event id |
7f453c24 PZ |
1353 | * to userspace. |
1354 | */ | |
cdd6c482 | 1355 | static u64 primary_event_id(struct perf_event *event) |
7f453c24 | 1356 | { |
cdd6c482 | 1357 | u64 id = event->id; |
7f453c24 | 1358 | |
cdd6c482 IM |
1359 | if (event->parent) |
1360 | id = event->parent->id; | |
7f453c24 PZ |
1361 | |
1362 | return id; | |
1363 | } | |
1364 | ||
25346b93 | 1365 | /* |
cdd6c482 | 1366 | * Get the perf_event_context for a task and lock it. |
63b6da39 | 1367 | * |
25346b93 PM |
1368 | * This has to cope with with the fact that until it is locked, |
1369 | * the context could get moved to another task. | |
1370 | */ | |
cdd6c482 | 1371 | static struct perf_event_context * |
8dc85d54 | 1372 | perf_lock_task_context(struct task_struct *task, int ctxn, unsigned long *flags) |
25346b93 | 1373 | { |
cdd6c482 | 1374 | struct perf_event_context *ctx; |
25346b93 | 1375 | |
9ed6060d | 1376 | retry: |
058ebd0e PZ |
1377 | /* |
1378 | * One of the few rules of preemptible RCU is that one cannot do | |
1379 | * rcu_read_unlock() while holding a scheduler (or nested) lock when | |
2fd59077 | 1380 | * part of the read side critical section was irqs-enabled -- see |
058ebd0e PZ |
1381 | * rcu_read_unlock_special(). |
1382 | * | |
1383 | * Since ctx->lock nests under rq->lock we must ensure the entire read | |
2fd59077 | 1384 | * side critical section has interrupts disabled. |
058ebd0e | 1385 | */ |
2fd59077 | 1386 | local_irq_save(*flags); |
058ebd0e | 1387 | rcu_read_lock(); |
8dc85d54 | 1388 | ctx = rcu_dereference(task->perf_event_ctxp[ctxn]); |
25346b93 PM |
1389 | if (ctx) { |
1390 | /* | |
1391 | * If this context is a clone of another, it might | |
1392 | * get swapped for another underneath us by | |
cdd6c482 | 1393 | * perf_event_task_sched_out, though the |
25346b93 PM |
1394 | * rcu_read_lock() protects us from any context |
1395 | * getting freed. Lock the context and check if it | |
1396 | * got swapped before we could get the lock, and retry | |
1397 | * if so. If we locked the right context, then it | |
1398 | * can't get swapped on us any more. | |
1399 | */ | |
2fd59077 | 1400 | raw_spin_lock(&ctx->lock); |
8dc85d54 | 1401 | if (ctx != rcu_dereference(task->perf_event_ctxp[ctxn])) { |
2fd59077 | 1402 | raw_spin_unlock(&ctx->lock); |
058ebd0e | 1403 | rcu_read_unlock(); |
2fd59077 | 1404 | local_irq_restore(*flags); |
25346b93 PM |
1405 | goto retry; |
1406 | } | |
b49a9e7e | 1407 | |
63b6da39 PZ |
1408 | if (ctx->task == TASK_TOMBSTONE || |
1409 | !atomic_inc_not_zero(&ctx->refcount)) { | |
2fd59077 | 1410 | raw_spin_unlock(&ctx->lock); |
b49a9e7e | 1411 | ctx = NULL; |
828b6f0e PZ |
1412 | } else { |
1413 | WARN_ON_ONCE(ctx->task != task); | |
b49a9e7e | 1414 | } |
25346b93 PM |
1415 | } |
1416 | rcu_read_unlock(); | |
2fd59077 PM |
1417 | if (!ctx) |
1418 | local_irq_restore(*flags); | |
25346b93 PM |
1419 | return ctx; |
1420 | } | |
1421 | ||
1422 | /* | |
1423 | * Get the context for a task and increment its pin_count so it | |
1424 | * can't get swapped to another task. This also increments its | |
1425 | * reference count so that the context can't get freed. | |
1426 | */ | |
8dc85d54 PZ |
1427 | static struct perf_event_context * |
1428 | perf_pin_task_context(struct task_struct *task, int ctxn) | |
25346b93 | 1429 | { |
cdd6c482 | 1430 | struct perf_event_context *ctx; |
25346b93 PM |
1431 | unsigned long flags; |
1432 | ||
8dc85d54 | 1433 | ctx = perf_lock_task_context(task, ctxn, &flags); |
25346b93 PM |
1434 | if (ctx) { |
1435 | ++ctx->pin_count; | |
e625cce1 | 1436 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1437 | } |
1438 | return ctx; | |
1439 | } | |
1440 | ||
cdd6c482 | 1441 | static void perf_unpin_context(struct perf_event_context *ctx) |
25346b93 PM |
1442 | { |
1443 | unsigned long flags; | |
1444 | ||
e625cce1 | 1445 | raw_spin_lock_irqsave(&ctx->lock, flags); |
25346b93 | 1446 | --ctx->pin_count; |
e625cce1 | 1447 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1448 | } |
1449 | ||
f67218c3 PZ |
1450 | /* |
1451 | * Update the record of the current time in a context. | |
1452 | */ | |
1453 | static void update_context_time(struct perf_event_context *ctx) | |
1454 | { | |
1455 | u64 now = perf_clock(); | |
1456 | ||
1457 | ctx->time += now - ctx->timestamp; | |
1458 | ctx->timestamp = now; | |
1459 | } | |
1460 | ||
4158755d SE |
1461 | static u64 perf_event_time(struct perf_event *event) |
1462 | { | |
1463 | struct perf_event_context *ctx = event->ctx; | |
e5d1367f SE |
1464 | |
1465 | if (is_cgroup_event(event)) | |
1466 | return perf_cgroup_event_time(event); | |
1467 | ||
4158755d SE |
1468 | return ctx ? ctx->time : 0; |
1469 | } | |
1470 | ||
487f05e1 AS |
1471 | static enum event_type_t get_event_type(struct perf_event *event) |
1472 | { | |
1473 | struct perf_event_context *ctx = event->ctx; | |
1474 | enum event_type_t event_type; | |
1475 | ||
1476 | lockdep_assert_held(&ctx->lock); | |
1477 | ||
3bda69c1 AS |
1478 | /* |
1479 | * It's 'group type', really, because if our group leader is | |
1480 | * pinned, so are we. | |
1481 | */ | |
1482 | if (event->group_leader != event) | |
1483 | event = event->group_leader; | |
1484 | ||
487f05e1 AS |
1485 | event_type = event->attr.pinned ? EVENT_PINNED : EVENT_FLEXIBLE; |
1486 | if (!ctx->task) | |
1487 | event_type |= EVENT_CPU; | |
1488 | ||
1489 | return event_type; | |
1490 | } | |
1491 | ||
889ff015 FW |
1492 | static struct list_head * |
1493 | ctx_group_list(struct perf_event *event, struct perf_event_context *ctx) | |
1494 | { | |
1495 | if (event->attr.pinned) | |
1496 | return &ctx->pinned_groups; | |
1497 | else | |
1498 | return &ctx->flexible_groups; | |
1499 | } | |
1500 | ||
fccc714b | 1501 | /* |
cdd6c482 | 1502 | * Add a event from the lists for its context. |
fccc714b PZ |
1503 | * Must be called with ctx->mutex and ctx->lock held. |
1504 | */ | |
04289bb9 | 1505 | static void |
cdd6c482 | 1506 | list_add_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1507 | { |
c994d613 PZ |
1508 | lockdep_assert_held(&ctx->lock); |
1509 | ||
8a49542c PZ |
1510 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); |
1511 | event->attach_state |= PERF_ATTACH_CONTEXT; | |
04289bb9 | 1512 | |
0d3d73aa PZ |
1513 | event->tstamp = perf_event_time(event); |
1514 | ||
04289bb9 | 1515 | /* |
8a49542c PZ |
1516 | * If we're a stand alone event or group leader, we go to the context |
1517 | * list, group events are kept attached to the group so that | |
1518 | * perf_group_detach can, at all times, locate all siblings. | |
04289bb9 | 1519 | */ |
8a49542c | 1520 | if (event->group_leader == event) { |
889ff015 FW |
1521 | struct list_head *list; |
1522 | ||
4ff6a8de | 1523 | event->group_caps = event->event_caps; |
d6f962b5 | 1524 | |
889ff015 FW |
1525 | list = ctx_group_list(event, ctx); |
1526 | list_add_tail(&event->group_entry, list); | |
5c148194 | 1527 | } |
592903cd | 1528 | |
db4a8356 | 1529 | list_update_cgroup_event(event, ctx, true); |
e5d1367f | 1530 | |
cdd6c482 IM |
1531 | list_add_rcu(&event->event_entry, &ctx->event_list); |
1532 | ctx->nr_events++; | |
1533 | if (event->attr.inherit_stat) | |
bfbd3381 | 1534 | ctx->nr_stat++; |
5a3126d4 PZ |
1535 | |
1536 | ctx->generation++; | |
04289bb9 IM |
1537 | } |
1538 | ||
0231bb53 JO |
1539 | /* |
1540 | * Initialize event state based on the perf_event_attr::disabled. | |
1541 | */ | |
1542 | static inline void perf_event__state_init(struct perf_event *event) | |
1543 | { | |
1544 | event->state = event->attr.disabled ? PERF_EVENT_STATE_OFF : | |
1545 | PERF_EVENT_STATE_INACTIVE; | |
1546 | } | |
1547 | ||
a723968c | 1548 | static void __perf_event_read_size(struct perf_event *event, int nr_siblings) |
c320c7b7 ACM |
1549 | { |
1550 | int entry = sizeof(u64); /* value */ | |
1551 | int size = 0; | |
1552 | int nr = 1; | |
1553 | ||
1554 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
1555 | size += sizeof(u64); | |
1556 | ||
1557 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
1558 | size += sizeof(u64); | |
1559 | ||
1560 | if (event->attr.read_format & PERF_FORMAT_ID) | |
1561 | entry += sizeof(u64); | |
1562 | ||
1563 | if (event->attr.read_format & PERF_FORMAT_GROUP) { | |
a723968c | 1564 | nr += nr_siblings; |
c320c7b7 ACM |
1565 | size += sizeof(u64); |
1566 | } | |
1567 | ||
1568 | size += entry * nr; | |
1569 | event->read_size = size; | |
1570 | } | |
1571 | ||
a723968c | 1572 | static void __perf_event_header_size(struct perf_event *event, u64 sample_type) |
c320c7b7 ACM |
1573 | { |
1574 | struct perf_sample_data *data; | |
c320c7b7 ACM |
1575 | u16 size = 0; |
1576 | ||
c320c7b7 ACM |
1577 | if (sample_type & PERF_SAMPLE_IP) |
1578 | size += sizeof(data->ip); | |
1579 | ||
6844c09d ACM |
1580 | if (sample_type & PERF_SAMPLE_ADDR) |
1581 | size += sizeof(data->addr); | |
1582 | ||
1583 | if (sample_type & PERF_SAMPLE_PERIOD) | |
1584 | size += sizeof(data->period); | |
1585 | ||
c3feedf2 AK |
1586 | if (sample_type & PERF_SAMPLE_WEIGHT) |
1587 | size += sizeof(data->weight); | |
1588 | ||
6844c09d ACM |
1589 | if (sample_type & PERF_SAMPLE_READ) |
1590 | size += event->read_size; | |
1591 | ||
d6be9ad6 SE |
1592 | if (sample_type & PERF_SAMPLE_DATA_SRC) |
1593 | size += sizeof(data->data_src.val); | |
1594 | ||
fdfbbd07 AK |
1595 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
1596 | size += sizeof(data->txn); | |
1597 | ||
fc7ce9c7 KL |
1598 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) |
1599 | size += sizeof(data->phys_addr); | |
1600 | ||
6844c09d ACM |
1601 | event->header_size = size; |
1602 | } | |
1603 | ||
a723968c PZ |
1604 | /* |
1605 | * Called at perf_event creation and when events are attached/detached from a | |
1606 | * group. | |
1607 | */ | |
1608 | static void perf_event__header_size(struct perf_event *event) | |
1609 | { | |
1610 | __perf_event_read_size(event, | |
1611 | event->group_leader->nr_siblings); | |
1612 | __perf_event_header_size(event, event->attr.sample_type); | |
1613 | } | |
1614 | ||
6844c09d ACM |
1615 | static void perf_event__id_header_size(struct perf_event *event) |
1616 | { | |
1617 | struct perf_sample_data *data; | |
1618 | u64 sample_type = event->attr.sample_type; | |
1619 | u16 size = 0; | |
1620 | ||
c320c7b7 ACM |
1621 | if (sample_type & PERF_SAMPLE_TID) |
1622 | size += sizeof(data->tid_entry); | |
1623 | ||
1624 | if (sample_type & PERF_SAMPLE_TIME) | |
1625 | size += sizeof(data->time); | |
1626 | ||
ff3d527c AH |
1627 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
1628 | size += sizeof(data->id); | |
1629 | ||
c320c7b7 ACM |
1630 | if (sample_type & PERF_SAMPLE_ID) |
1631 | size += sizeof(data->id); | |
1632 | ||
1633 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
1634 | size += sizeof(data->stream_id); | |
1635 | ||
1636 | if (sample_type & PERF_SAMPLE_CPU) | |
1637 | size += sizeof(data->cpu_entry); | |
1638 | ||
6844c09d | 1639 | event->id_header_size = size; |
c320c7b7 ACM |
1640 | } |
1641 | ||
a723968c PZ |
1642 | static bool perf_event_validate_size(struct perf_event *event) |
1643 | { | |
1644 | /* | |
1645 | * The values computed here will be over-written when we actually | |
1646 | * attach the event. | |
1647 | */ | |
1648 | __perf_event_read_size(event, event->group_leader->nr_siblings + 1); | |
1649 | __perf_event_header_size(event, event->attr.sample_type & ~PERF_SAMPLE_READ); | |
1650 | perf_event__id_header_size(event); | |
1651 | ||
1652 | /* | |
1653 | * Sum the lot; should not exceed the 64k limit we have on records. | |
1654 | * Conservative limit to allow for callchains and other variable fields. | |
1655 | */ | |
1656 | if (event->read_size + event->header_size + | |
1657 | event->id_header_size + sizeof(struct perf_event_header) >= 16*1024) | |
1658 | return false; | |
1659 | ||
1660 | return true; | |
1661 | } | |
1662 | ||
8a49542c PZ |
1663 | static void perf_group_attach(struct perf_event *event) |
1664 | { | |
c320c7b7 | 1665 | struct perf_event *group_leader = event->group_leader, *pos; |
8a49542c | 1666 | |
a76a82a3 PZ |
1667 | lockdep_assert_held(&event->ctx->lock); |
1668 | ||
74c3337c PZ |
1669 | /* |
1670 | * We can have double attach due to group movement in perf_event_open. | |
1671 | */ | |
1672 | if (event->attach_state & PERF_ATTACH_GROUP) | |
1673 | return; | |
1674 | ||
8a49542c PZ |
1675 | event->attach_state |= PERF_ATTACH_GROUP; |
1676 | ||
1677 | if (group_leader == event) | |
1678 | return; | |
1679 | ||
652884fe PZ |
1680 | WARN_ON_ONCE(group_leader->ctx != event->ctx); |
1681 | ||
4ff6a8de | 1682 | group_leader->group_caps &= event->event_caps; |
8a49542c PZ |
1683 | |
1684 | list_add_tail(&event->group_entry, &group_leader->sibling_list); | |
1685 | group_leader->nr_siblings++; | |
c320c7b7 ACM |
1686 | |
1687 | perf_event__header_size(group_leader); | |
1688 | ||
1689 | list_for_each_entry(pos, &group_leader->sibling_list, group_entry) | |
1690 | perf_event__header_size(pos); | |
8a49542c PZ |
1691 | } |
1692 | ||
a63eaf34 | 1693 | /* |
cdd6c482 | 1694 | * Remove a event from the lists for its context. |
fccc714b | 1695 | * Must be called with ctx->mutex and ctx->lock held. |
a63eaf34 | 1696 | */ |
04289bb9 | 1697 | static void |
cdd6c482 | 1698 | list_del_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1699 | { |
652884fe PZ |
1700 | WARN_ON_ONCE(event->ctx != ctx); |
1701 | lockdep_assert_held(&ctx->lock); | |
1702 | ||
8a49542c PZ |
1703 | /* |
1704 | * We can have double detach due to exit/hot-unplug + close. | |
1705 | */ | |
1706 | if (!(event->attach_state & PERF_ATTACH_CONTEXT)) | |
a63eaf34 | 1707 | return; |
8a49542c PZ |
1708 | |
1709 | event->attach_state &= ~PERF_ATTACH_CONTEXT; | |
1710 | ||
db4a8356 | 1711 | list_update_cgroup_event(event, ctx, false); |
e5d1367f | 1712 | |
cdd6c482 IM |
1713 | ctx->nr_events--; |
1714 | if (event->attr.inherit_stat) | |
bfbd3381 | 1715 | ctx->nr_stat--; |
8bc20959 | 1716 | |
cdd6c482 | 1717 | list_del_rcu(&event->event_entry); |
04289bb9 | 1718 | |
8a49542c PZ |
1719 | if (event->group_leader == event) |
1720 | list_del_init(&event->group_entry); | |
5c148194 | 1721 | |
b2e74a26 SE |
1722 | /* |
1723 | * If event was in error state, then keep it | |
1724 | * that way, otherwise bogus counts will be | |
1725 | * returned on read(). The only way to get out | |
1726 | * of error state is by explicit re-enabling | |
1727 | * of the event | |
1728 | */ | |
1729 | if (event->state > PERF_EVENT_STATE_OFF) | |
0d3d73aa | 1730 | perf_event_set_state(event, PERF_EVENT_STATE_OFF); |
5a3126d4 PZ |
1731 | |
1732 | ctx->generation++; | |
050735b0 PZ |
1733 | } |
1734 | ||
8a49542c | 1735 | static void perf_group_detach(struct perf_event *event) |
050735b0 PZ |
1736 | { |
1737 | struct perf_event *sibling, *tmp; | |
8a49542c PZ |
1738 | struct list_head *list = NULL; |
1739 | ||
a76a82a3 PZ |
1740 | lockdep_assert_held(&event->ctx->lock); |
1741 | ||
8a49542c PZ |
1742 | /* |
1743 | * We can have double detach due to exit/hot-unplug + close. | |
1744 | */ | |
1745 | if (!(event->attach_state & PERF_ATTACH_GROUP)) | |
1746 | return; | |
1747 | ||
1748 | event->attach_state &= ~PERF_ATTACH_GROUP; | |
1749 | ||
1750 | /* | |
1751 | * If this is a sibling, remove it from its group. | |
1752 | */ | |
1753 | if (event->group_leader != event) { | |
1754 | list_del_init(&event->group_entry); | |
1755 | event->group_leader->nr_siblings--; | |
c320c7b7 | 1756 | goto out; |
8a49542c PZ |
1757 | } |
1758 | ||
1759 | if (!list_empty(&event->group_entry)) | |
1760 | list = &event->group_entry; | |
2e2af50b | 1761 | |
04289bb9 | 1762 | /* |
cdd6c482 IM |
1763 | * If this was a group event with sibling events then |
1764 | * upgrade the siblings to singleton events by adding them | |
8a49542c | 1765 | * to whatever list we are on. |
04289bb9 | 1766 | */ |
cdd6c482 | 1767 | list_for_each_entry_safe(sibling, tmp, &event->sibling_list, group_entry) { |
8a49542c PZ |
1768 | if (list) |
1769 | list_move_tail(&sibling->group_entry, list); | |
04289bb9 | 1770 | sibling->group_leader = sibling; |
d6f962b5 FW |
1771 | |
1772 | /* Inherit group flags from the previous leader */ | |
4ff6a8de | 1773 | sibling->group_caps = event->group_caps; |
652884fe PZ |
1774 | |
1775 | WARN_ON_ONCE(sibling->ctx != event->ctx); | |
04289bb9 | 1776 | } |
c320c7b7 ACM |
1777 | |
1778 | out: | |
1779 | perf_event__header_size(event->group_leader); | |
1780 | ||
1781 | list_for_each_entry(tmp, &event->group_leader->sibling_list, group_entry) | |
1782 | perf_event__header_size(tmp); | |
04289bb9 IM |
1783 | } |
1784 | ||
fadfe7be JO |
1785 | static bool is_orphaned_event(struct perf_event *event) |
1786 | { | |
a69b0ca4 | 1787 | return event->state == PERF_EVENT_STATE_DEAD; |
fadfe7be JO |
1788 | } |
1789 | ||
2c81a647 | 1790 | static inline int __pmu_filter_match(struct perf_event *event) |
66eb579e MR |
1791 | { |
1792 | struct pmu *pmu = event->pmu; | |
1793 | return pmu->filter_match ? pmu->filter_match(event) : 1; | |
1794 | } | |
1795 | ||
2c81a647 MR |
1796 | /* |
1797 | * Check whether we should attempt to schedule an event group based on | |
1798 | * PMU-specific filtering. An event group can consist of HW and SW events, | |
1799 | * potentially with a SW leader, so we must check all the filters, to | |
1800 | * determine whether a group is schedulable: | |
1801 | */ | |
1802 | static inline int pmu_filter_match(struct perf_event *event) | |
1803 | { | |
1804 | struct perf_event *child; | |
1805 | ||
1806 | if (!__pmu_filter_match(event)) | |
1807 | return 0; | |
1808 | ||
1809 | list_for_each_entry(child, &event->sibling_list, group_entry) { | |
1810 | if (!__pmu_filter_match(child)) | |
1811 | return 0; | |
1812 | } | |
1813 | ||
1814 | return 1; | |
1815 | } | |
1816 | ||
fa66f07a SE |
1817 | static inline int |
1818 | event_filter_match(struct perf_event *event) | |
1819 | { | |
0b8f1e2e PZ |
1820 | return (event->cpu == -1 || event->cpu == smp_processor_id()) && |
1821 | perf_cgroup_match(event) && pmu_filter_match(event); | |
fa66f07a SE |
1822 | } |
1823 | ||
9ffcfa6f SE |
1824 | static void |
1825 | event_sched_out(struct perf_event *event, | |
3b6f9e5c | 1826 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 1827 | struct perf_event_context *ctx) |
3b6f9e5c | 1828 | { |
0d3d73aa | 1829 | enum perf_event_state state = PERF_EVENT_STATE_INACTIVE; |
652884fe PZ |
1830 | |
1831 | WARN_ON_ONCE(event->ctx != ctx); | |
1832 | lockdep_assert_held(&ctx->lock); | |
1833 | ||
cdd6c482 | 1834 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
9ffcfa6f | 1835 | return; |
3b6f9e5c | 1836 | |
44377277 AS |
1837 | perf_pmu_disable(event->pmu); |
1838 | ||
28a967c3 PZ |
1839 | event->pmu->del(event, 0); |
1840 | event->oncpu = -1; | |
0d3d73aa | 1841 | |
ac69b885 PZ |
1842 | if (READ_ONCE(event->pending_disable) >= 0) { |
1843 | WRITE_ONCE(event->pending_disable, -1); | |
0d3d73aa | 1844 | state = PERF_EVENT_STATE_OFF; |
970892a9 | 1845 | } |
0d3d73aa | 1846 | perf_event_set_state(event, state); |
3b6f9e5c | 1847 | |
cdd6c482 | 1848 | if (!is_software_event(event)) |
3b6f9e5c | 1849 | cpuctx->active_oncpu--; |
2fde4f94 MR |
1850 | if (!--ctx->nr_active) |
1851 | perf_event_ctx_deactivate(ctx); | |
0f5a2601 PZ |
1852 | if (event->attr.freq && event->attr.sample_freq) |
1853 | ctx->nr_freq--; | |
cdd6c482 | 1854 | if (event->attr.exclusive || !cpuctx->active_oncpu) |
3b6f9e5c | 1855 | cpuctx->exclusive = 0; |
44377277 AS |
1856 | |
1857 | perf_pmu_enable(event->pmu); | |
3b6f9e5c PM |
1858 | } |
1859 | ||
d859e29f | 1860 | static void |
cdd6c482 | 1861 | group_sched_out(struct perf_event *group_event, |
d859e29f | 1862 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 1863 | struct perf_event_context *ctx) |
d859e29f | 1864 | { |
cdd6c482 | 1865 | struct perf_event *event; |
0d3d73aa PZ |
1866 | |
1867 | if (group_event->state != PERF_EVENT_STATE_ACTIVE) | |
1868 | return; | |
d859e29f | 1869 | |
3f005e7d MR |
1870 | perf_pmu_disable(ctx->pmu); |
1871 | ||
cdd6c482 | 1872 | event_sched_out(group_event, cpuctx, ctx); |
d859e29f PM |
1873 | |
1874 | /* | |
1875 | * Schedule out siblings (if any): | |
1876 | */ | |
cdd6c482 IM |
1877 | list_for_each_entry(event, &group_event->sibling_list, group_entry) |
1878 | event_sched_out(event, cpuctx, ctx); | |
d859e29f | 1879 | |
3f005e7d MR |
1880 | perf_pmu_enable(ctx->pmu); |
1881 | ||
0d3d73aa | 1882 | if (group_event->attr.exclusive) |
d859e29f PM |
1883 | cpuctx->exclusive = 0; |
1884 | } | |
1885 | ||
45a0e07a | 1886 | #define DETACH_GROUP 0x01UL |
0017960f | 1887 | |
0793a61d | 1888 | /* |
cdd6c482 | 1889 | * Cross CPU call to remove a performance event |
0793a61d | 1890 | * |
cdd6c482 | 1891 | * We disable the event on the hardware level first. After that we |
0793a61d TG |
1892 | * remove it from the context list. |
1893 | */ | |
fae3fde6 PZ |
1894 | static void |
1895 | __perf_remove_from_context(struct perf_event *event, | |
1896 | struct perf_cpu_context *cpuctx, | |
1897 | struct perf_event_context *ctx, | |
1898 | void *info) | |
0793a61d | 1899 | { |
45a0e07a | 1900 | unsigned long flags = (unsigned long)info; |
0793a61d | 1901 | |
3c5c8711 PZ |
1902 | if (ctx->is_active & EVENT_TIME) { |
1903 | update_context_time(ctx); | |
1904 | update_cgrp_time_from_cpuctx(cpuctx); | |
1905 | } | |
1906 | ||
cdd6c482 | 1907 | event_sched_out(event, cpuctx, ctx); |
45a0e07a | 1908 | if (flags & DETACH_GROUP) |
46ce0fe9 | 1909 | perf_group_detach(event); |
cdd6c482 | 1910 | list_del_event(event, ctx); |
39a43640 PZ |
1911 | |
1912 | if (!ctx->nr_events && ctx->is_active) { | |
64ce3126 | 1913 | ctx->is_active = 0; |
39a43640 PZ |
1914 | if (ctx->task) { |
1915 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
1916 | cpuctx->task_ctx = NULL; | |
1917 | } | |
64ce3126 | 1918 | } |
0793a61d TG |
1919 | } |
1920 | ||
0793a61d | 1921 | /* |
cdd6c482 | 1922 | * Remove the event from a task's (or a CPU's) list of events. |
0793a61d | 1923 | * |
cdd6c482 IM |
1924 | * If event->ctx is a cloned context, callers must make sure that |
1925 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 PM |
1926 | * remains valid. This is OK when called from perf_release since |
1927 | * that only calls us on the top-level context, which can't be a clone. | |
cdd6c482 | 1928 | * When called from perf_event_exit_task, it's OK because the |
c93f7669 | 1929 | * context has been detached from its task. |
0793a61d | 1930 | */ |
45a0e07a | 1931 | static void perf_remove_from_context(struct perf_event *event, unsigned long flags) |
0793a61d | 1932 | { |
a76a82a3 PZ |
1933 | struct perf_event_context *ctx = event->ctx; |
1934 | ||
1935 | lockdep_assert_held(&ctx->mutex); | |
0793a61d | 1936 | |
45a0e07a | 1937 | event_function_call(event, __perf_remove_from_context, (void *)flags); |
a76a82a3 PZ |
1938 | |
1939 | /* | |
1940 | * The above event_function_call() can NO-OP when it hits | |
1941 | * TASK_TOMBSTONE. In that case we must already have been detached | |
1942 | * from the context (by perf_event_exit_event()) but the grouping | |
1943 | * might still be in-tact. | |
1944 | */ | |
1945 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); | |
1946 | if ((flags & DETACH_GROUP) && | |
1947 | (event->attach_state & PERF_ATTACH_GROUP)) { | |
1948 | /* | |
1949 | * Since in that case we cannot possibly be scheduled, simply | |
1950 | * detach now. | |
1951 | */ | |
1952 | raw_spin_lock_irq(&ctx->lock); | |
1953 | perf_group_detach(event); | |
1954 | raw_spin_unlock_irq(&ctx->lock); | |
1955 | } | |
0793a61d TG |
1956 | } |
1957 | ||
d859e29f | 1958 | /* |
cdd6c482 | 1959 | * Cross CPU call to disable a performance event |
d859e29f | 1960 | */ |
fae3fde6 PZ |
1961 | static void __perf_event_disable(struct perf_event *event, |
1962 | struct perf_cpu_context *cpuctx, | |
1963 | struct perf_event_context *ctx, | |
1964 | void *info) | |
7b648018 | 1965 | { |
fae3fde6 PZ |
1966 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
1967 | return; | |
7b648018 | 1968 | |
3c5c8711 PZ |
1969 | if (ctx->is_active & EVENT_TIME) { |
1970 | update_context_time(ctx); | |
1971 | update_cgrp_time_from_event(event); | |
1972 | } | |
1973 | ||
fae3fde6 PZ |
1974 | if (event == event->group_leader) |
1975 | group_sched_out(event, cpuctx, ctx); | |
1976 | else | |
1977 | event_sched_out(event, cpuctx, ctx); | |
0d3d73aa PZ |
1978 | |
1979 | perf_event_set_state(event, PERF_EVENT_STATE_OFF); | |
7b648018 PZ |
1980 | } |
1981 | ||
d859e29f | 1982 | /* |
cdd6c482 | 1983 | * Disable a event. |
c93f7669 | 1984 | * |
cdd6c482 IM |
1985 | * If event->ctx is a cloned context, callers must make sure that |
1986 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 1987 | * remains valid. This condition is satisifed when called through |
cdd6c482 IM |
1988 | * perf_event_for_each_child or perf_event_for_each because they |
1989 | * hold the top-level event's child_mutex, so any descendant that | |
8ba289b8 PZ |
1990 | * goes to exit will block in perf_event_exit_event(). |
1991 | * | |
cdd6c482 | 1992 | * When called from perf_pending_event it's OK because event->ctx |
c93f7669 | 1993 | * is the current context on this CPU and preemption is disabled, |
cdd6c482 | 1994 | * hence we can't get into perf_event_task_sched_out for this context. |
d859e29f | 1995 | */ |
f63a8daa | 1996 | static void _perf_event_disable(struct perf_event *event) |
d859e29f | 1997 | { |
cdd6c482 | 1998 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 1999 | |
e625cce1 | 2000 | raw_spin_lock_irq(&ctx->lock); |
7b648018 | 2001 | if (event->state <= PERF_EVENT_STATE_OFF) { |
e625cce1 | 2002 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 2003 | return; |
53cfbf59 | 2004 | } |
e625cce1 | 2005 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 2006 | |
fae3fde6 PZ |
2007 | event_function_call(event, __perf_event_disable, NULL); |
2008 | } | |
2009 | ||
2010 | void perf_event_disable_local(struct perf_event *event) | |
2011 | { | |
2012 | event_function_local(event, __perf_event_disable, NULL); | |
d859e29f | 2013 | } |
f63a8daa PZ |
2014 | |
2015 | /* | |
2016 | * Strictly speaking kernel users cannot create groups and therefore this | |
2017 | * interface does not need the perf_event_ctx_lock() magic. | |
2018 | */ | |
2019 | void perf_event_disable(struct perf_event *event) | |
2020 | { | |
2021 | struct perf_event_context *ctx; | |
2022 | ||
2023 | ctx = perf_event_ctx_lock(event); | |
2024 | _perf_event_disable(event); | |
2025 | perf_event_ctx_unlock(event, ctx); | |
2026 | } | |
dcfce4a0 | 2027 | EXPORT_SYMBOL_GPL(perf_event_disable); |
d859e29f | 2028 | |
5aab90ce JO |
2029 | void perf_event_disable_inatomic(struct perf_event *event) |
2030 | { | |
ac69b885 PZ |
2031 | WRITE_ONCE(event->pending_disable, smp_processor_id()); |
2032 | /* can fail, see perf_pending_event_disable() */ | |
5aab90ce JO |
2033 | irq_work_queue(&event->pending); |
2034 | } | |
2035 | ||
e5d1367f | 2036 | static void perf_set_shadow_time(struct perf_event *event, |
0d3d73aa | 2037 | struct perf_event_context *ctx) |
e5d1367f SE |
2038 | { |
2039 | /* | |
2040 | * use the correct time source for the time snapshot | |
2041 | * | |
2042 | * We could get by without this by leveraging the | |
2043 | * fact that to get to this function, the caller | |
2044 | * has most likely already called update_context_time() | |
2045 | * and update_cgrp_time_xx() and thus both timestamp | |
2046 | * are identical (or very close). Given that tstamp is, | |
2047 | * already adjusted for cgroup, we could say that: | |
2048 | * tstamp - ctx->timestamp | |
2049 | * is equivalent to | |
2050 | * tstamp - cgrp->timestamp. | |
2051 | * | |
2052 | * Then, in perf_output_read(), the calculation would | |
2053 | * work with no changes because: | |
2054 | * - event is guaranteed scheduled in | |
2055 | * - no scheduled out in between | |
2056 | * - thus the timestamp would be the same | |
2057 | * | |
2058 | * But this is a bit hairy. | |
2059 | * | |
2060 | * So instead, we have an explicit cgroup call to remain | |
2061 | * within the time time source all along. We believe it | |
2062 | * is cleaner and simpler to understand. | |
2063 | */ | |
2064 | if (is_cgroup_event(event)) | |
0d3d73aa | 2065 | perf_cgroup_set_shadow_time(event, event->tstamp); |
e5d1367f | 2066 | else |
0d3d73aa | 2067 | event->shadow_ctx_time = event->tstamp - ctx->timestamp; |
e5d1367f SE |
2068 | } |
2069 | ||
4fe757dd PZ |
2070 | #define MAX_INTERRUPTS (~0ULL) |
2071 | ||
2072 | static void perf_log_throttle(struct perf_event *event, int enable); | |
ec0d7729 | 2073 | static void perf_log_itrace_start(struct perf_event *event); |
4fe757dd | 2074 | |
235c7fc7 | 2075 | static int |
9ffcfa6f | 2076 | event_sched_in(struct perf_event *event, |
235c7fc7 | 2077 | struct perf_cpu_context *cpuctx, |
6e37738a | 2078 | struct perf_event_context *ctx) |
235c7fc7 | 2079 | { |
44377277 | 2080 | int ret = 0; |
4158755d | 2081 | |
63342411 PZ |
2082 | lockdep_assert_held(&ctx->lock); |
2083 | ||
cdd6c482 | 2084 | if (event->state <= PERF_EVENT_STATE_OFF) |
235c7fc7 IM |
2085 | return 0; |
2086 | ||
95ff4ca2 AS |
2087 | WRITE_ONCE(event->oncpu, smp_processor_id()); |
2088 | /* | |
0c1cbc18 PZ |
2089 | * Order event::oncpu write to happen before the ACTIVE state is |
2090 | * visible. This allows perf_event_{stop,read}() to observe the correct | |
2091 | * ->oncpu if it sees ACTIVE. | |
95ff4ca2 AS |
2092 | */ |
2093 | smp_wmb(); | |
0d3d73aa | 2094 | perf_event_set_state(event, PERF_EVENT_STATE_ACTIVE); |
4fe757dd PZ |
2095 | |
2096 | /* | |
2097 | * Unthrottle events, since we scheduled we might have missed several | |
2098 | * ticks already, also for a heavily scheduling task there is little | |
2099 | * guarantee it'll get a tick in a timely manner. | |
2100 | */ | |
2101 | if (unlikely(event->hw.interrupts == MAX_INTERRUPTS)) { | |
2102 | perf_log_throttle(event, 1); | |
2103 | event->hw.interrupts = 0; | |
2104 | } | |
2105 | ||
44377277 AS |
2106 | perf_pmu_disable(event->pmu); |
2107 | ||
0d3d73aa | 2108 | perf_set_shadow_time(event, ctx); |
72f669c0 | 2109 | |
ec0d7729 AS |
2110 | perf_log_itrace_start(event); |
2111 | ||
a4eaf7f1 | 2112 | if (event->pmu->add(event, PERF_EF_START)) { |
0d3d73aa | 2113 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
cdd6c482 | 2114 | event->oncpu = -1; |
44377277 AS |
2115 | ret = -EAGAIN; |
2116 | goto out; | |
235c7fc7 IM |
2117 | } |
2118 | ||
cdd6c482 | 2119 | if (!is_software_event(event)) |
3b6f9e5c | 2120 | cpuctx->active_oncpu++; |
2fde4f94 MR |
2121 | if (!ctx->nr_active++) |
2122 | perf_event_ctx_activate(ctx); | |
0f5a2601 PZ |
2123 | if (event->attr.freq && event->attr.sample_freq) |
2124 | ctx->nr_freq++; | |
235c7fc7 | 2125 | |
cdd6c482 | 2126 | if (event->attr.exclusive) |
3b6f9e5c PM |
2127 | cpuctx->exclusive = 1; |
2128 | ||
44377277 AS |
2129 | out: |
2130 | perf_pmu_enable(event->pmu); | |
2131 | ||
2132 | return ret; | |
235c7fc7 IM |
2133 | } |
2134 | ||
6751b71e | 2135 | static int |
cdd6c482 | 2136 | group_sched_in(struct perf_event *group_event, |
6751b71e | 2137 | struct perf_cpu_context *cpuctx, |
6e37738a | 2138 | struct perf_event_context *ctx) |
6751b71e | 2139 | { |
6bde9b6c | 2140 | struct perf_event *event, *partial_group = NULL; |
4a234593 | 2141 | struct pmu *pmu = ctx->pmu; |
6751b71e | 2142 | |
cdd6c482 | 2143 | if (group_event->state == PERF_EVENT_STATE_OFF) |
6751b71e PM |
2144 | return 0; |
2145 | ||
fbbe0701 | 2146 | pmu->start_txn(pmu, PERF_PMU_TXN_ADD); |
6bde9b6c | 2147 | |
9ffcfa6f | 2148 | if (event_sched_in(group_event, cpuctx, ctx)) { |
ad5133b7 | 2149 | pmu->cancel_txn(pmu); |
272325c4 | 2150 | perf_mux_hrtimer_restart(cpuctx); |
6751b71e | 2151 | return -EAGAIN; |
90151c35 | 2152 | } |
6751b71e PM |
2153 | |
2154 | /* | |
2155 | * Schedule in siblings as one group (if any): | |
2156 | */ | |
cdd6c482 | 2157 | list_for_each_entry(event, &group_event->sibling_list, group_entry) { |
9ffcfa6f | 2158 | if (event_sched_in(event, cpuctx, ctx)) { |
cdd6c482 | 2159 | partial_group = event; |
6751b71e PM |
2160 | goto group_error; |
2161 | } | |
2162 | } | |
2163 | ||
9ffcfa6f | 2164 | if (!pmu->commit_txn(pmu)) |
6e85158c | 2165 | return 0; |
9ffcfa6f | 2166 | |
6751b71e PM |
2167 | group_error: |
2168 | /* | |
2169 | * Groups can be scheduled in as one unit only, so undo any | |
2170 | * partial group before returning: | |
0d3d73aa | 2171 | * The events up to the failed event are scheduled out normally. |
6751b71e | 2172 | */ |
cdd6c482 IM |
2173 | list_for_each_entry(event, &group_event->sibling_list, group_entry) { |
2174 | if (event == partial_group) | |
0d3d73aa | 2175 | break; |
d7842da4 | 2176 | |
0d3d73aa | 2177 | event_sched_out(event, cpuctx, ctx); |
6751b71e | 2178 | } |
9ffcfa6f | 2179 | event_sched_out(group_event, cpuctx, ctx); |
6751b71e | 2180 | |
ad5133b7 | 2181 | pmu->cancel_txn(pmu); |
90151c35 | 2182 | |
272325c4 | 2183 | perf_mux_hrtimer_restart(cpuctx); |
9e630205 | 2184 | |
6751b71e PM |
2185 | return -EAGAIN; |
2186 | } | |
2187 | ||
3b6f9e5c | 2188 | /* |
cdd6c482 | 2189 | * Work out whether we can put this event group on the CPU now. |
3b6f9e5c | 2190 | */ |
cdd6c482 | 2191 | static int group_can_go_on(struct perf_event *event, |
3b6f9e5c PM |
2192 | struct perf_cpu_context *cpuctx, |
2193 | int can_add_hw) | |
2194 | { | |
2195 | /* | |
cdd6c482 | 2196 | * Groups consisting entirely of software events can always go on. |
3b6f9e5c | 2197 | */ |
4ff6a8de | 2198 | if (event->group_caps & PERF_EV_CAP_SOFTWARE) |
3b6f9e5c PM |
2199 | return 1; |
2200 | /* | |
2201 | * If an exclusive group is already on, no other hardware | |
cdd6c482 | 2202 | * events can go on. |
3b6f9e5c PM |
2203 | */ |
2204 | if (cpuctx->exclusive) | |
2205 | return 0; | |
2206 | /* | |
2207 | * If this group is exclusive and there are already | |
cdd6c482 | 2208 | * events on the CPU, it can't go on. |
3b6f9e5c | 2209 | */ |
cdd6c482 | 2210 | if (event->attr.exclusive && cpuctx->active_oncpu) |
3b6f9e5c PM |
2211 | return 0; |
2212 | /* | |
2213 | * Otherwise, try to add it if all previous groups were able | |
2214 | * to go on. | |
2215 | */ | |
2216 | return can_add_hw; | |
2217 | } | |
2218 | ||
cdd6c482 IM |
2219 | static void add_event_to_ctx(struct perf_event *event, |
2220 | struct perf_event_context *ctx) | |
53cfbf59 | 2221 | { |
cdd6c482 | 2222 | list_add_event(event, ctx); |
8a49542c | 2223 | perf_group_attach(event); |
53cfbf59 PM |
2224 | } |
2225 | ||
bd2afa49 PZ |
2226 | static void ctx_sched_out(struct perf_event_context *ctx, |
2227 | struct perf_cpu_context *cpuctx, | |
2228 | enum event_type_t event_type); | |
2c29ef0f PZ |
2229 | static void |
2230 | ctx_sched_in(struct perf_event_context *ctx, | |
2231 | struct perf_cpu_context *cpuctx, | |
2232 | enum event_type_t event_type, | |
2233 | struct task_struct *task); | |
fe4b04fa | 2234 | |
bd2afa49 | 2235 | static void task_ctx_sched_out(struct perf_cpu_context *cpuctx, |
487f05e1 AS |
2236 | struct perf_event_context *ctx, |
2237 | enum event_type_t event_type) | |
bd2afa49 PZ |
2238 | { |
2239 | if (!cpuctx->task_ctx) | |
2240 | return; | |
2241 | ||
2242 | if (WARN_ON_ONCE(ctx != cpuctx->task_ctx)) | |
2243 | return; | |
2244 | ||
487f05e1 | 2245 | ctx_sched_out(ctx, cpuctx, event_type); |
bd2afa49 PZ |
2246 | } |
2247 | ||
dce5855b PZ |
2248 | static void perf_event_sched_in(struct perf_cpu_context *cpuctx, |
2249 | struct perf_event_context *ctx, | |
2250 | struct task_struct *task) | |
2251 | { | |
2252 | cpu_ctx_sched_in(cpuctx, EVENT_PINNED, task); | |
2253 | if (ctx) | |
2254 | ctx_sched_in(ctx, cpuctx, EVENT_PINNED, task); | |
2255 | cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE, task); | |
2256 | if (ctx) | |
2257 | ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE, task); | |
2258 | } | |
2259 | ||
487f05e1 AS |
2260 | /* |
2261 | * We want to maintain the following priority of scheduling: | |
2262 | * - CPU pinned (EVENT_CPU | EVENT_PINNED) | |
2263 | * - task pinned (EVENT_PINNED) | |
2264 | * - CPU flexible (EVENT_CPU | EVENT_FLEXIBLE) | |
2265 | * - task flexible (EVENT_FLEXIBLE). | |
2266 | * | |
2267 | * In order to avoid unscheduling and scheduling back in everything every | |
2268 | * time an event is added, only do it for the groups of equal priority and | |
2269 | * below. | |
2270 | * | |
2271 | * This can be called after a batch operation on task events, in which case | |
2272 | * event_type is a bit mask of the types of events involved. For CPU events, | |
2273 | * event_type is only either EVENT_PINNED or EVENT_FLEXIBLE. | |
2274 | */ | |
3e349507 | 2275 | static void ctx_resched(struct perf_cpu_context *cpuctx, |
487f05e1 AS |
2276 | struct perf_event_context *task_ctx, |
2277 | enum event_type_t event_type) | |
0017960f | 2278 | { |
732fd871 | 2279 | enum event_type_t ctx_event_type; |
487f05e1 AS |
2280 | bool cpu_event = !!(event_type & EVENT_CPU); |
2281 | ||
2282 | /* | |
2283 | * If pinned groups are involved, flexible groups also need to be | |
2284 | * scheduled out. | |
2285 | */ | |
2286 | if (event_type & EVENT_PINNED) | |
2287 | event_type |= EVENT_FLEXIBLE; | |
2288 | ||
732fd871 SL |
2289 | ctx_event_type = event_type & EVENT_ALL; |
2290 | ||
3e349507 PZ |
2291 | perf_pmu_disable(cpuctx->ctx.pmu); |
2292 | if (task_ctx) | |
487f05e1 AS |
2293 | task_ctx_sched_out(cpuctx, task_ctx, event_type); |
2294 | ||
2295 | /* | |
2296 | * Decide which cpu ctx groups to schedule out based on the types | |
2297 | * of events that caused rescheduling: | |
2298 | * - EVENT_CPU: schedule out corresponding groups; | |
2299 | * - EVENT_PINNED task events: schedule out EVENT_FLEXIBLE groups; | |
2300 | * - otherwise, do nothing more. | |
2301 | */ | |
2302 | if (cpu_event) | |
2303 | cpu_ctx_sched_out(cpuctx, ctx_event_type); | |
2304 | else if (ctx_event_type & EVENT_PINNED) | |
2305 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
2306 | ||
3e349507 PZ |
2307 | perf_event_sched_in(cpuctx, task_ctx, current); |
2308 | perf_pmu_enable(cpuctx->ctx.pmu); | |
0017960f PZ |
2309 | } |
2310 | ||
0793a61d | 2311 | /* |
cdd6c482 | 2312 | * Cross CPU call to install and enable a performance event |
682076ae | 2313 | * |
a096309b PZ |
2314 | * Very similar to remote_function() + event_function() but cannot assume that |
2315 | * things like ctx->is_active and cpuctx->task_ctx are set. | |
0793a61d | 2316 | */ |
fe4b04fa | 2317 | static int __perf_install_in_context(void *info) |
0793a61d | 2318 | { |
a096309b PZ |
2319 | struct perf_event *event = info; |
2320 | struct perf_event_context *ctx = event->ctx; | |
108b02cf | 2321 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
2c29ef0f | 2322 | struct perf_event_context *task_ctx = cpuctx->task_ctx; |
63cae12b | 2323 | bool reprogram = true; |
a096309b | 2324 | int ret = 0; |
0793a61d | 2325 | |
63b6da39 | 2326 | raw_spin_lock(&cpuctx->ctx.lock); |
39a43640 | 2327 | if (ctx->task) { |
b58f6b0d PZ |
2328 | raw_spin_lock(&ctx->lock); |
2329 | task_ctx = ctx; | |
a096309b | 2330 | |
63cae12b | 2331 | reprogram = (ctx->task == current); |
b58f6b0d | 2332 | |
39a43640 | 2333 | /* |
63cae12b PZ |
2334 | * If the task is running, it must be running on this CPU, |
2335 | * otherwise we cannot reprogram things. | |
2336 | * | |
2337 | * If its not running, we don't care, ctx->lock will | |
2338 | * serialize against it becoming runnable. | |
39a43640 | 2339 | */ |
63cae12b PZ |
2340 | if (task_curr(ctx->task) && !reprogram) { |
2341 | ret = -ESRCH; | |
2342 | goto unlock; | |
2343 | } | |
a096309b | 2344 | |
63cae12b | 2345 | WARN_ON_ONCE(reprogram && cpuctx->task_ctx && cpuctx->task_ctx != ctx); |
63b6da39 PZ |
2346 | } else if (task_ctx) { |
2347 | raw_spin_lock(&task_ctx->lock); | |
2c29ef0f | 2348 | } |
b58f6b0d | 2349 | |
fcb3f8a6 | 2350 | #ifdef CONFIG_CGROUP_PERF |
2351 | if (is_cgroup_event(event)) { | |
2352 | /* | |
2353 | * If the current cgroup doesn't match the event's | |
2354 | * cgroup, we should not try to schedule it. | |
2355 | */ | |
2356 | struct perf_cgroup *cgrp = perf_cgroup_from_task(current, ctx); | |
2357 | reprogram = cgroup_is_descendant(cgrp->css.cgroup, | |
2358 | event->cgrp->css.cgroup); | |
2359 | } | |
2360 | #endif | |
2361 | ||
63cae12b | 2362 | if (reprogram) { |
a096309b PZ |
2363 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
2364 | add_event_to_ctx(event, ctx); | |
487f05e1 | 2365 | ctx_resched(cpuctx, task_ctx, get_event_type(event)); |
a096309b PZ |
2366 | } else { |
2367 | add_event_to_ctx(event, ctx); | |
2368 | } | |
2369 | ||
63b6da39 | 2370 | unlock: |
2c29ef0f | 2371 | perf_ctx_unlock(cpuctx, task_ctx); |
fe4b04fa | 2372 | |
a096309b | 2373 | return ret; |
0793a61d TG |
2374 | } |
2375 | ||
2376 | /* | |
a096309b PZ |
2377 | * Attach a performance event to a context. |
2378 | * | |
2379 | * Very similar to event_function_call, see comment there. | |
0793a61d TG |
2380 | */ |
2381 | static void | |
cdd6c482 IM |
2382 | perf_install_in_context(struct perf_event_context *ctx, |
2383 | struct perf_event *event, | |
0793a61d TG |
2384 | int cpu) |
2385 | { | |
a096309b | 2386 | struct task_struct *task = READ_ONCE(ctx->task); |
39a43640 | 2387 | |
fe4b04fa PZ |
2388 | lockdep_assert_held(&ctx->mutex); |
2389 | ||
0cda4c02 YZ |
2390 | if (event->cpu != -1) |
2391 | event->cpu = cpu; | |
c3f00c70 | 2392 | |
0b8f1e2e PZ |
2393 | /* |
2394 | * Ensures that if we can observe event->ctx, both the event and ctx | |
2395 | * will be 'complete'. See perf_iterate_sb_cpu(). | |
2396 | */ | |
2397 | smp_store_release(&event->ctx, ctx); | |
2398 | ||
a096309b PZ |
2399 | if (!task) { |
2400 | cpu_function_call(cpu, __perf_install_in_context, event); | |
2401 | return; | |
2402 | } | |
2403 | ||
2404 | /* | |
2405 | * Should not happen, we validate the ctx is still alive before calling. | |
2406 | */ | |
2407 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) | |
2408 | return; | |
2409 | ||
39a43640 PZ |
2410 | /* |
2411 | * Installing events is tricky because we cannot rely on ctx->is_active | |
2412 | * to be set in case this is the nr_events 0 -> 1 transition. | |
63cae12b PZ |
2413 | * |
2414 | * Instead we use task_curr(), which tells us if the task is running. | |
2415 | * However, since we use task_curr() outside of rq::lock, we can race | |
2416 | * against the actual state. This means the result can be wrong. | |
2417 | * | |
2418 | * If we get a false positive, we retry, this is harmless. | |
2419 | * | |
2420 | * If we get a false negative, things are complicated. If we are after | |
2421 | * perf_event_context_sched_in() ctx::lock will serialize us, and the | |
2422 | * value must be correct. If we're before, it doesn't matter since | |
2423 | * perf_event_context_sched_in() will program the counter. | |
2424 | * | |
2425 | * However, this hinges on the remote context switch having observed | |
2426 | * our task->perf_event_ctxp[] store, such that it will in fact take | |
2427 | * ctx::lock in perf_event_context_sched_in(). | |
2428 | * | |
2429 | * We do this by task_function_call(), if the IPI fails to hit the task | |
2430 | * we know any future context switch of task must see the | |
2431 | * perf_event_ctpx[] store. | |
39a43640 | 2432 | */ |
63cae12b | 2433 | |
63b6da39 | 2434 | /* |
63cae12b PZ |
2435 | * This smp_mb() orders the task->perf_event_ctxp[] store with the |
2436 | * task_cpu() load, such that if the IPI then does not find the task | |
2437 | * running, a future context switch of that task must observe the | |
2438 | * store. | |
63b6da39 | 2439 | */ |
63cae12b PZ |
2440 | smp_mb(); |
2441 | again: | |
2442 | if (!task_function_call(task, __perf_install_in_context, event)) | |
a096309b PZ |
2443 | return; |
2444 | ||
2445 | raw_spin_lock_irq(&ctx->lock); | |
2446 | task = ctx->task; | |
84c4e620 | 2447 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) { |
a096309b PZ |
2448 | /* |
2449 | * Cannot happen because we already checked above (which also | |
2450 | * cannot happen), and we hold ctx->mutex, which serializes us | |
2451 | * against perf_event_exit_task_context(). | |
2452 | */ | |
63b6da39 PZ |
2453 | raw_spin_unlock_irq(&ctx->lock); |
2454 | return; | |
2455 | } | |
39a43640 | 2456 | /* |
63cae12b PZ |
2457 | * If the task is not running, ctx->lock will avoid it becoming so, |
2458 | * thus we can safely install the event. | |
39a43640 | 2459 | */ |
63cae12b PZ |
2460 | if (task_curr(task)) { |
2461 | raw_spin_unlock_irq(&ctx->lock); | |
2462 | goto again; | |
2463 | } | |
2464 | add_event_to_ctx(event, ctx); | |
2465 | raw_spin_unlock_irq(&ctx->lock); | |
0793a61d TG |
2466 | } |
2467 | ||
d859e29f | 2468 | /* |
cdd6c482 | 2469 | * Cross CPU call to enable a performance event |
d859e29f | 2470 | */ |
fae3fde6 PZ |
2471 | static void __perf_event_enable(struct perf_event *event, |
2472 | struct perf_cpu_context *cpuctx, | |
2473 | struct perf_event_context *ctx, | |
2474 | void *info) | |
04289bb9 | 2475 | { |
cdd6c482 | 2476 | struct perf_event *leader = event->group_leader; |
fae3fde6 | 2477 | struct perf_event_context *task_ctx; |
04289bb9 | 2478 | |
6e801e01 PZ |
2479 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2480 | event->state <= PERF_EVENT_STATE_ERROR) | |
fae3fde6 | 2481 | return; |
3cbed429 | 2482 | |
bd2afa49 PZ |
2483 | if (ctx->is_active) |
2484 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); | |
2485 | ||
0d3d73aa | 2486 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
04289bb9 | 2487 | |
fae3fde6 PZ |
2488 | if (!ctx->is_active) |
2489 | return; | |
2490 | ||
e5d1367f | 2491 | if (!event_filter_match(event)) { |
bd2afa49 | 2492 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); |
fae3fde6 | 2493 | return; |
e5d1367f | 2494 | } |
f4c4176f | 2495 | |
04289bb9 | 2496 | /* |
cdd6c482 | 2497 | * If the event is in a group and isn't the group leader, |
d859e29f | 2498 | * then don't put it on unless the group is on. |
04289bb9 | 2499 | */ |
bd2afa49 PZ |
2500 | if (leader != event && leader->state != PERF_EVENT_STATE_ACTIVE) { |
2501 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
fae3fde6 | 2502 | return; |
bd2afa49 | 2503 | } |
fe4b04fa | 2504 | |
fae3fde6 PZ |
2505 | task_ctx = cpuctx->task_ctx; |
2506 | if (ctx->task) | |
2507 | WARN_ON_ONCE(task_ctx != ctx); | |
d859e29f | 2508 | |
487f05e1 | 2509 | ctx_resched(cpuctx, task_ctx, get_event_type(event)); |
7b648018 PZ |
2510 | } |
2511 | ||
d859e29f | 2512 | /* |
cdd6c482 | 2513 | * Enable a event. |
c93f7669 | 2514 | * |
cdd6c482 IM |
2515 | * If event->ctx is a cloned context, callers must make sure that |
2516 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 2517 | * remains valid. This condition is satisfied when called through |
cdd6c482 IM |
2518 | * perf_event_for_each_child or perf_event_for_each as described |
2519 | * for perf_event_disable. | |
d859e29f | 2520 | */ |
f63a8daa | 2521 | static void _perf_event_enable(struct perf_event *event) |
d859e29f | 2522 | { |
cdd6c482 | 2523 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 2524 | |
7b648018 | 2525 | raw_spin_lock_irq(&ctx->lock); |
6e801e01 PZ |
2526 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2527 | event->state < PERF_EVENT_STATE_ERROR) { | |
7b648018 | 2528 | raw_spin_unlock_irq(&ctx->lock); |
d859e29f PM |
2529 | return; |
2530 | } | |
2531 | ||
d859e29f | 2532 | /* |
cdd6c482 | 2533 | * If the event is in error state, clear that first. |
7b648018 PZ |
2534 | * |
2535 | * That way, if we see the event in error state below, we know that it | |
2536 | * has gone back into error state, as distinct from the task having | |
2537 | * been scheduled away before the cross-call arrived. | |
d859e29f | 2538 | */ |
cdd6c482 IM |
2539 | if (event->state == PERF_EVENT_STATE_ERROR) |
2540 | event->state = PERF_EVENT_STATE_OFF; | |
e625cce1 | 2541 | raw_spin_unlock_irq(&ctx->lock); |
fe4b04fa | 2542 | |
fae3fde6 | 2543 | event_function_call(event, __perf_event_enable, NULL); |
d859e29f | 2544 | } |
f63a8daa PZ |
2545 | |
2546 | /* | |
2547 | * See perf_event_disable(); | |
2548 | */ | |
2549 | void perf_event_enable(struct perf_event *event) | |
2550 | { | |
2551 | struct perf_event_context *ctx; | |
2552 | ||
2553 | ctx = perf_event_ctx_lock(event); | |
2554 | _perf_event_enable(event); | |
2555 | perf_event_ctx_unlock(event, ctx); | |
2556 | } | |
dcfce4a0 | 2557 | EXPORT_SYMBOL_GPL(perf_event_enable); |
d859e29f | 2558 | |
375637bc AS |
2559 | struct stop_event_data { |
2560 | struct perf_event *event; | |
2561 | unsigned int restart; | |
2562 | }; | |
2563 | ||
95ff4ca2 AS |
2564 | static int __perf_event_stop(void *info) |
2565 | { | |
375637bc AS |
2566 | struct stop_event_data *sd = info; |
2567 | struct perf_event *event = sd->event; | |
95ff4ca2 | 2568 | |
375637bc | 2569 | /* if it's already INACTIVE, do nothing */ |
95ff4ca2 AS |
2570 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) |
2571 | return 0; | |
2572 | ||
2573 | /* matches smp_wmb() in event_sched_in() */ | |
2574 | smp_rmb(); | |
2575 | ||
2576 | /* | |
2577 | * There is a window with interrupts enabled before we get here, | |
2578 | * so we need to check again lest we try to stop another CPU's event. | |
2579 | */ | |
2580 | if (READ_ONCE(event->oncpu) != smp_processor_id()) | |
2581 | return -EAGAIN; | |
2582 | ||
2583 | event->pmu->stop(event, PERF_EF_UPDATE); | |
2584 | ||
375637bc AS |
2585 | /* |
2586 | * May race with the actual stop (through perf_pmu_output_stop()), | |
2587 | * but it is only used for events with AUX ring buffer, and such | |
2588 | * events will refuse to restart because of rb::aux_mmap_count==0, | |
2589 | * see comments in perf_aux_output_begin(). | |
2590 | * | |
2591 | * Since this is happening on a event-local CPU, no trace is lost | |
2592 | * while restarting. | |
2593 | */ | |
2594 | if (sd->restart) | |
c9bbdd48 | 2595 | event->pmu->start(event, 0); |
375637bc | 2596 | |
95ff4ca2 AS |
2597 | return 0; |
2598 | } | |
2599 | ||
767ae086 | 2600 | static int perf_event_stop(struct perf_event *event, int restart) |
375637bc AS |
2601 | { |
2602 | struct stop_event_data sd = { | |
2603 | .event = event, | |
767ae086 | 2604 | .restart = restart, |
375637bc AS |
2605 | }; |
2606 | int ret = 0; | |
2607 | ||
2608 | do { | |
2609 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) | |
2610 | return 0; | |
2611 | ||
2612 | /* matches smp_wmb() in event_sched_in() */ | |
2613 | smp_rmb(); | |
2614 | ||
2615 | /* | |
2616 | * We only want to restart ACTIVE events, so if the event goes | |
2617 | * inactive here (event->oncpu==-1), there's nothing more to do; | |
2618 | * fall through with ret==-ENXIO. | |
2619 | */ | |
2620 | ret = cpu_function_call(READ_ONCE(event->oncpu), | |
2621 | __perf_event_stop, &sd); | |
2622 | } while (ret == -EAGAIN); | |
2623 | ||
2624 | return ret; | |
2625 | } | |
2626 | ||
2627 | /* | |
2628 | * In order to contain the amount of racy and tricky in the address filter | |
2629 | * configuration management, it is a two part process: | |
2630 | * | |
2631 | * (p1) when userspace mappings change as a result of (1) or (2) or (3) below, | |
2632 | * we update the addresses of corresponding vmas in | |
2633 | * event::addr_filters_offs array and bump the event::addr_filters_gen; | |
2634 | * (p2) when an event is scheduled in (pmu::add), it calls | |
2635 | * perf_event_addr_filters_sync() which calls pmu::addr_filters_sync() | |
2636 | * if the generation has changed since the previous call. | |
2637 | * | |
2638 | * If (p1) happens while the event is active, we restart it to force (p2). | |
2639 | * | |
2640 | * (1) perf_addr_filters_apply(): adjusting filters' offsets based on | |
2641 | * pre-existing mappings, called once when new filters arrive via SET_FILTER | |
2642 | * ioctl; | |
2643 | * (2) perf_addr_filters_adjust(): adjusting filters' offsets based on newly | |
2644 | * registered mapping, called for every new mmap(), with mm::mmap_sem down | |
2645 | * for reading; | |
2646 | * (3) perf_event_addr_filters_exec(): clearing filters' offsets in the process | |
2647 | * of exec. | |
2648 | */ | |
2649 | void perf_event_addr_filters_sync(struct perf_event *event) | |
2650 | { | |
2651 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
2652 | ||
2653 | if (!has_addr_filter(event)) | |
2654 | return; | |
2655 | ||
2656 | raw_spin_lock(&ifh->lock); | |
2657 | if (event->addr_filters_gen != event->hw.addr_filters_gen) { | |
2658 | event->pmu->addr_filters_sync(event); | |
2659 | event->hw.addr_filters_gen = event->addr_filters_gen; | |
2660 | } | |
2661 | raw_spin_unlock(&ifh->lock); | |
2662 | } | |
2663 | EXPORT_SYMBOL_GPL(perf_event_addr_filters_sync); | |
2664 | ||
f63a8daa | 2665 | static int _perf_event_refresh(struct perf_event *event, int refresh) |
79f14641 | 2666 | { |
2023b359 | 2667 | /* |
cdd6c482 | 2668 | * not supported on inherited events |
2023b359 | 2669 | */ |
2e939d1d | 2670 | if (event->attr.inherit || !is_sampling_event(event)) |
2023b359 PZ |
2671 | return -EINVAL; |
2672 | ||
cdd6c482 | 2673 | atomic_add(refresh, &event->event_limit); |
f63a8daa | 2674 | _perf_event_enable(event); |
2023b359 PZ |
2675 | |
2676 | return 0; | |
79f14641 | 2677 | } |
f63a8daa PZ |
2678 | |
2679 | /* | |
2680 | * See perf_event_disable() | |
2681 | */ | |
2682 | int perf_event_refresh(struct perf_event *event, int refresh) | |
2683 | { | |
2684 | struct perf_event_context *ctx; | |
2685 | int ret; | |
2686 | ||
2687 | ctx = perf_event_ctx_lock(event); | |
2688 | ret = _perf_event_refresh(event, refresh); | |
2689 | perf_event_ctx_unlock(event, ctx); | |
2690 | ||
2691 | return ret; | |
2692 | } | |
26ca5c11 | 2693 | EXPORT_SYMBOL_GPL(perf_event_refresh); |
79f14641 | 2694 | |
5b0311e1 FW |
2695 | static void ctx_sched_out(struct perf_event_context *ctx, |
2696 | struct perf_cpu_context *cpuctx, | |
2697 | enum event_type_t event_type) | |
235c7fc7 | 2698 | { |
db24d33e | 2699 | int is_active = ctx->is_active; |
c994d613 | 2700 | struct perf_event *event; |
235c7fc7 | 2701 | |
c994d613 | 2702 | lockdep_assert_held(&ctx->lock); |
235c7fc7 | 2703 | |
39a43640 PZ |
2704 | if (likely(!ctx->nr_events)) { |
2705 | /* | |
2706 | * See __perf_remove_from_context(). | |
2707 | */ | |
2708 | WARN_ON_ONCE(ctx->is_active); | |
2709 | if (ctx->task) | |
2710 | WARN_ON_ONCE(cpuctx->task_ctx); | |
facc4307 | 2711 | return; |
39a43640 PZ |
2712 | } |
2713 | ||
db24d33e | 2714 | ctx->is_active &= ~event_type; |
3cbaa590 PZ |
2715 | if (!(ctx->is_active & EVENT_ALL)) |
2716 | ctx->is_active = 0; | |
2717 | ||
63e30d3e PZ |
2718 | if (ctx->task) { |
2719 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
2720 | if (!ctx->is_active) | |
2721 | cpuctx->task_ctx = NULL; | |
2722 | } | |
facc4307 | 2723 | |
8fdc6539 PZ |
2724 | /* |
2725 | * Always update time if it was set; not only when it changes. | |
2726 | * Otherwise we can 'forget' to update time for any but the last | |
2727 | * context we sched out. For example: | |
2728 | * | |
2729 | * ctx_sched_out(.event_type = EVENT_FLEXIBLE) | |
2730 | * ctx_sched_out(.event_type = EVENT_PINNED) | |
2731 | * | |
2732 | * would only update time for the pinned events. | |
2733 | */ | |
3cbaa590 PZ |
2734 | if (is_active & EVENT_TIME) { |
2735 | /* update (and stop) ctx time */ | |
2736 | update_context_time(ctx); | |
2737 | update_cgrp_time_from_cpuctx(cpuctx); | |
2738 | } | |
2739 | ||
8fdc6539 PZ |
2740 | is_active ^= ctx->is_active; /* changed bits */ |
2741 | ||
3cbaa590 | 2742 | if (!ctx->nr_active || !(is_active & EVENT_ALL)) |
facc4307 | 2743 | return; |
5b0311e1 | 2744 | |
075e0b00 | 2745 | perf_pmu_disable(ctx->pmu); |
3cbaa590 | 2746 | if (is_active & EVENT_PINNED) { |
889ff015 FW |
2747 | list_for_each_entry(event, &ctx->pinned_groups, group_entry) |
2748 | group_sched_out(event, cpuctx, ctx); | |
9ed6060d | 2749 | } |
889ff015 | 2750 | |
3cbaa590 | 2751 | if (is_active & EVENT_FLEXIBLE) { |
889ff015 | 2752 | list_for_each_entry(event, &ctx->flexible_groups, group_entry) |
8c9ed8e1 | 2753 | group_sched_out(event, cpuctx, ctx); |
9ed6060d | 2754 | } |
1b9a644f | 2755 | perf_pmu_enable(ctx->pmu); |
235c7fc7 IM |
2756 | } |
2757 | ||
564c2b21 | 2758 | /* |
5a3126d4 PZ |
2759 | * Test whether two contexts are equivalent, i.e. whether they have both been |
2760 | * cloned from the same version of the same context. | |
2761 | * | |
2762 | * Equivalence is measured using a generation number in the context that is | |
2763 | * incremented on each modification to it; see unclone_ctx(), list_add_event() | |
2764 | * and list_del_event(). | |
564c2b21 | 2765 | */ |
cdd6c482 IM |
2766 | static int context_equiv(struct perf_event_context *ctx1, |
2767 | struct perf_event_context *ctx2) | |
564c2b21 | 2768 | { |
211de6eb PZ |
2769 | lockdep_assert_held(&ctx1->lock); |
2770 | lockdep_assert_held(&ctx2->lock); | |
2771 | ||
5a3126d4 PZ |
2772 | /* Pinning disables the swap optimization */ |
2773 | if (ctx1->pin_count || ctx2->pin_count) | |
2774 | return 0; | |
2775 | ||
2776 | /* If ctx1 is the parent of ctx2 */ | |
2777 | if (ctx1 == ctx2->parent_ctx && ctx1->generation == ctx2->parent_gen) | |
2778 | return 1; | |
2779 | ||
2780 | /* If ctx2 is the parent of ctx1 */ | |
2781 | if (ctx1->parent_ctx == ctx2 && ctx1->parent_gen == ctx2->generation) | |
2782 | return 1; | |
2783 | ||
2784 | /* | |
2785 | * If ctx1 and ctx2 have the same parent; we flatten the parent | |
2786 | * hierarchy, see perf_event_init_context(). | |
2787 | */ | |
2788 | if (ctx1->parent_ctx && ctx1->parent_ctx == ctx2->parent_ctx && | |
2789 | ctx1->parent_gen == ctx2->parent_gen) | |
2790 | return 1; | |
2791 | ||
2792 | /* Unmatched */ | |
2793 | return 0; | |
564c2b21 PM |
2794 | } |
2795 | ||
cdd6c482 IM |
2796 | static void __perf_event_sync_stat(struct perf_event *event, |
2797 | struct perf_event *next_event) | |
bfbd3381 PZ |
2798 | { |
2799 | u64 value; | |
2800 | ||
cdd6c482 | 2801 | if (!event->attr.inherit_stat) |
bfbd3381 PZ |
2802 | return; |
2803 | ||
2804 | /* | |
cdd6c482 | 2805 | * Update the event value, we cannot use perf_event_read() |
bfbd3381 PZ |
2806 | * because we're in the middle of a context switch and have IRQs |
2807 | * disabled, which upsets smp_call_function_single(), however | |
cdd6c482 | 2808 | * we know the event must be on the current CPU, therefore we |
bfbd3381 PZ |
2809 | * don't need to use it. |
2810 | */ | |
0d3d73aa | 2811 | if (event->state == PERF_EVENT_STATE_ACTIVE) |
3dbebf15 | 2812 | event->pmu->read(event); |
bfbd3381 | 2813 | |
0d3d73aa | 2814 | perf_event_update_time(event); |
bfbd3381 PZ |
2815 | |
2816 | /* | |
cdd6c482 | 2817 | * In order to keep per-task stats reliable we need to flip the event |
bfbd3381 PZ |
2818 | * values when we flip the contexts. |
2819 | */ | |
e7850595 PZ |
2820 | value = local64_read(&next_event->count); |
2821 | value = local64_xchg(&event->count, value); | |
2822 | local64_set(&next_event->count, value); | |
bfbd3381 | 2823 | |
cdd6c482 IM |
2824 | swap(event->total_time_enabled, next_event->total_time_enabled); |
2825 | swap(event->total_time_running, next_event->total_time_running); | |
19d2e755 | 2826 | |
bfbd3381 | 2827 | /* |
19d2e755 | 2828 | * Since we swizzled the values, update the user visible data too. |
bfbd3381 | 2829 | */ |
cdd6c482 IM |
2830 | perf_event_update_userpage(event); |
2831 | perf_event_update_userpage(next_event); | |
bfbd3381 PZ |
2832 | } |
2833 | ||
cdd6c482 IM |
2834 | static void perf_event_sync_stat(struct perf_event_context *ctx, |
2835 | struct perf_event_context *next_ctx) | |
bfbd3381 | 2836 | { |
cdd6c482 | 2837 | struct perf_event *event, *next_event; |
bfbd3381 PZ |
2838 | |
2839 | if (!ctx->nr_stat) | |
2840 | return; | |
2841 | ||
02ffdbc8 PZ |
2842 | update_context_time(ctx); |
2843 | ||
cdd6c482 IM |
2844 | event = list_first_entry(&ctx->event_list, |
2845 | struct perf_event, event_entry); | |
bfbd3381 | 2846 | |
cdd6c482 IM |
2847 | next_event = list_first_entry(&next_ctx->event_list, |
2848 | struct perf_event, event_entry); | |
bfbd3381 | 2849 | |
cdd6c482 IM |
2850 | while (&event->event_entry != &ctx->event_list && |
2851 | &next_event->event_entry != &next_ctx->event_list) { | |
bfbd3381 | 2852 | |
cdd6c482 | 2853 | __perf_event_sync_stat(event, next_event); |
bfbd3381 | 2854 | |
cdd6c482 IM |
2855 | event = list_next_entry(event, event_entry); |
2856 | next_event = list_next_entry(next_event, event_entry); | |
bfbd3381 PZ |
2857 | } |
2858 | } | |
2859 | ||
fe4b04fa PZ |
2860 | static void perf_event_context_sched_out(struct task_struct *task, int ctxn, |
2861 | struct task_struct *next) | |
0793a61d | 2862 | { |
8dc85d54 | 2863 | struct perf_event_context *ctx = task->perf_event_ctxp[ctxn]; |
cdd6c482 | 2864 | struct perf_event_context *next_ctx; |
5a3126d4 | 2865 | struct perf_event_context *parent, *next_parent; |
108b02cf | 2866 | struct perf_cpu_context *cpuctx; |
c93f7669 | 2867 | int do_switch = 1; |
0793a61d | 2868 | |
108b02cf PZ |
2869 | if (likely(!ctx)) |
2870 | return; | |
10989fb2 | 2871 | |
108b02cf PZ |
2872 | cpuctx = __get_cpu_context(ctx); |
2873 | if (!cpuctx->task_ctx) | |
0793a61d TG |
2874 | return; |
2875 | ||
c93f7669 | 2876 | rcu_read_lock(); |
8dc85d54 | 2877 | next_ctx = next->perf_event_ctxp[ctxn]; |
5a3126d4 PZ |
2878 | if (!next_ctx) |
2879 | goto unlock; | |
2880 | ||
2881 | parent = rcu_dereference(ctx->parent_ctx); | |
2882 | next_parent = rcu_dereference(next_ctx->parent_ctx); | |
2883 | ||
2884 | /* If neither context have a parent context; they cannot be clones. */ | |
802c8a61 | 2885 | if (!parent && !next_parent) |
5a3126d4 PZ |
2886 | goto unlock; |
2887 | ||
2888 | if (next_parent == ctx || next_ctx == parent || next_parent == parent) { | |
c93f7669 PM |
2889 | /* |
2890 | * Looks like the two contexts are clones, so we might be | |
2891 | * able to optimize the context switch. We lock both | |
2892 | * contexts and check that they are clones under the | |
2893 | * lock (including re-checking that neither has been | |
2894 | * uncloned in the meantime). It doesn't matter which | |
2895 | * order we take the locks because no other cpu could | |
2896 | * be trying to lock both of these tasks. | |
2897 | */ | |
e625cce1 TG |
2898 | raw_spin_lock(&ctx->lock); |
2899 | raw_spin_lock_nested(&next_ctx->lock, SINGLE_DEPTH_NESTING); | |
c93f7669 | 2900 | if (context_equiv(ctx, next_ctx)) { |
63b6da39 PZ |
2901 | WRITE_ONCE(ctx->task, next); |
2902 | WRITE_ONCE(next_ctx->task, task); | |
5a158c3c YZ |
2903 | |
2904 | swap(ctx->task_ctx_data, next_ctx->task_ctx_data); | |
2905 | ||
63b6da39 PZ |
2906 | /* |
2907 | * RCU_INIT_POINTER here is safe because we've not | |
2908 | * modified the ctx and the above modification of | |
2909 | * ctx->task and ctx->task_ctx_data are immaterial | |
2910 | * since those values are always verified under | |
2911 | * ctx->lock which we're now holding. | |
2912 | */ | |
2913 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], next_ctx); | |
2914 | RCU_INIT_POINTER(next->perf_event_ctxp[ctxn], ctx); | |
2915 | ||
c93f7669 | 2916 | do_switch = 0; |
bfbd3381 | 2917 | |
cdd6c482 | 2918 | perf_event_sync_stat(ctx, next_ctx); |
c93f7669 | 2919 | } |
e625cce1 TG |
2920 | raw_spin_unlock(&next_ctx->lock); |
2921 | raw_spin_unlock(&ctx->lock); | |
564c2b21 | 2922 | } |
5a3126d4 | 2923 | unlock: |
c93f7669 | 2924 | rcu_read_unlock(); |
564c2b21 | 2925 | |
c93f7669 | 2926 | if (do_switch) { |
facc4307 | 2927 | raw_spin_lock(&ctx->lock); |
487f05e1 | 2928 | task_ctx_sched_out(cpuctx, ctx, EVENT_ALL); |
facc4307 | 2929 | raw_spin_unlock(&ctx->lock); |
c93f7669 | 2930 | } |
0793a61d TG |
2931 | } |
2932 | ||
e48c1788 PZ |
2933 | static DEFINE_PER_CPU(struct list_head, sched_cb_list); |
2934 | ||
ba532500 YZ |
2935 | void perf_sched_cb_dec(struct pmu *pmu) |
2936 | { | |
e48c1788 PZ |
2937 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
2938 | ||
ba532500 | 2939 | this_cpu_dec(perf_sched_cb_usages); |
e48c1788 PZ |
2940 | |
2941 | if (!--cpuctx->sched_cb_usage) | |
2942 | list_del(&cpuctx->sched_cb_entry); | |
ba532500 YZ |
2943 | } |
2944 | ||
e48c1788 | 2945 | |
ba532500 YZ |
2946 | void perf_sched_cb_inc(struct pmu *pmu) |
2947 | { | |
e48c1788 PZ |
2948 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
2949 | ||
2950 | if (!cpuctx->sched_cb_usage++) | |
2951 | list_add(&cpuctx->sched_cb_entry, this_cpu_ptr(&sched_cb_list)); | |
2952 | ||
ba532500 YZ |
2953 | this_cpu_inc(perf_sched_cb_usages); |
2954 | } | |
2955 | ||
2956 | /* | |
2957 | * This function provides the context switch callback to the lower code | |
2958 | * layer. It is invoked ONLY when the context switch callback is enabled. | |
09e61b4f PZ |
2959 | * |
2960 | * This callback is relevant even to per-cpu events; for example multi event | |
2961 | * PEBS requires this to provide PID/TID information. This requires we flush | |
2962 | * all queued PEBS records before we context switch to a new task. | |
ba532500 YZ |
2963 | */ |
2964 | static void perf_pmu_sched_task(struct task_struct *prev, | |
2965 | struct task_struct *next, | |
2966 | bool sched_in) | |
2967 | { | |
2968 | struct perf_cpu_context *cpuctx; | |
2969 | struct pmu *pmu; | |
ba532500 YZ |
2970 | |
2971 | if (prev == next) | |
2972 | return; | |
2973 | ||
e48c1788 | 2974 | list_for_each_entry(cpuctx, this_cpu_ptr(&sched_cb_list), sched_cb_entry) { |
1fd7e416 | 2975 | pmu = cpuctx->ctx.pmu; /* software PMUs will not have sched_task */ |
ba532500 | 2976 | |
e48c1788 PZ |
2977 | if (WARN_ON_ONCE(!pmu->sched_task)) |
2978 | continue; | |
ba532500 | 2979 | |
e48c1788 PZ |
2980 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
2981 | perf_pmu_disable(pmu); | |
ba532500 | 2982 | |
e48c1788 | 2983 | pmu->sched_task(cpuctx->task_ctx, sched_in); |
ba532500 | 2984 | |
e48c1788 PZ |
2985 | perf_pmu_enable(pmu); |
2986 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
ba532500 | 2987 | } |
ba532500 YZ |
2988 | } |
2989 | ||
45ac1403 AH |
2990 | static void perf_event_switch(struct task_struct *task, |
2991 | struct task_struct *next_prev, bool sched_in); | |
2992 | ||
8dc85d54 PZ |
2993 | #define for_each_task_context_nr(ctxn) \ |
2994 | for ((ctxn) = 0; (ctxn) < perf_nr_task_contexts; (ctxn)++) | |
2995 | ||
2996 | /* | |
2997 | * Called from scheduler to remove the events of the current task, | |
2998 | * with interrupts disabled. | |
2999 | * | |
3000 | * We stop each event and update the event value in event->count. | |
3001 | * | |
3002 | * This does not protect us against NMI, but disable() | |
3003 | * sets the disabled bit in the control field of event _before_ | |
3004 | * accessing the event control register. If a NMI hits, then it will | |
3005 | * not restart the event. | |
3006 | */ | |
ab0cce56 JO |
3007 | void __perf_event_task_sched_out(struct task_struct *task, |
3008 | struct task_struct *next) | |
8dc85d54 PZ |
3009 | { |
3010 | int ctxn; | |
3011 | ||
ba532500 YZ |
3012 | if (__this_cpu_read(perf_sched_cb_usages)) |
3013 | perf_pmu_sched_task(task, next, false); | |
3014 | ||
45ac1403 AH |
3015 | if (atomic_read(&nr_switch_events)) |
3016 | perf_event_switch(task, next, false); | |
3017 | ||
8dc85d54 PZ |
3018 | for_each_task_context_nr(ctxn) |
3019 | perf_event_context_sched_out(task, ctxn, next); | |
e5d1367f SE |
3020 | |
3021 | /* | |
3022 | * if cgroup events exist on this CPU, then we need | |
3023 | * to check if we have to switch out PMU state. | |
3024 | * cgroup event are system-wide mode only | |
3025 | */ | |
4a32fea9 | 3026 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) |
a8d757ef | 3027 | perf_cgroup_sched_out(task, next); |
8dc85d54 PZ |
3028 | } |
3029 | ||
5b0311e1 FW |
3030 | /* |
3031 | * Called with IRQs disabled | |
3032 | */ | |
3033 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, | |
3034 | enum event_type_t event_type) | |
3035 | { | |
3036 | ctx_sched_out(&cpuctx->ctx, cpuctx, event_type); | |
04289bb9 IM |
3037 | } |
3038 | ||
235c7fc7 | 3039 | static void |
5b0311e1 | 3040 | ctx_pinned_sched_in(struct perf_event_context *ctx, |
6e37738a | 3041 | struct perf_cpu_context *cpuctx) |
0793a61d | 3042 | { |
cdd6c482 | 3043 | struct perf_event *event; |
0793a61d | 3044 | |
889ff015 FW |
3045 | list_for_each_entry(event, &ctx->pinned_groups, group_entry) { |
3046 | if (event->state <= PERF_EVENT_STATE_OFF) | |
3b6f9e5c | 3047 | continue; |
5632ab12 | 3048 | if (!event_filter_match(event)) |
3b6f9e5c PM |
3049 | continue; |
3050 | ||
8c9ed8e1 | 3051 | if (group_can_go_on(event, cpuctx, 1)) |
6e37738a | 3052 | group_sched_in(event, cpuctx, ctx); |
3b6f9e5c PM |
3053 | |
3054 | /* | |
3055 | * If this pinned group hasn't been scheduled, | |
3056 | * put it in error state. | |
3057 | */ | |
0d3d73aa PZ |
3058 | if (event->state == PERF_EVENT_STATE_INACTIVE) |
3059 | perf_event_set_state(event, PERF_EVENT_STATE_ERROR); | |
3b6f9e5c | 3060 | } |
5b0311e1 FW |
3061 | } |
3062 | ||
3063 | static void | |
3064 | ctx_flexible_sched_in(struct perf_event_context *ctx, | |
6e37738a | 3065 | struct perf_cpu_context *cpuctx) |
5b0311e1 FW |
3066 | { |
3067 | struct perf_event *event; | |
3068 | int can_add_hw = 1; | |
3b6f9e5c | 3069 | |
889ff015 FW |
3070 | list_for_each_entry(event, &ctx->flexible_groups, group_entry) { |
3071 | /* Ignore events in OFF or ERROR state */ | |
3072 | if (event->state <= PERF_EVENT_STATE_OFF) | |
3b6f9e5c | 3073 | continue; |
04289bb9 IM |
3074 | /* |
3075 | * Listen to the 'cpu' scheduling filter constraint | |
cdd6c482 | 3076 | * of events: |
04289bb9 | 3077 | */ |
5632ab12 | 3078 | if (!event_filter_match(event)) |
0793a61d TG |
3079 | continue; |
3080 | ||
9ed6060d | 3081 | if (group_can_go_on(event, cpuctx, can_add_hw)) { |
6e37738a | 3082 | if (group_sched_in(event, cpuctx, ctx)) |
dd0e6ba2 | 3083 | can_add_hw = 0; |
9ed6060d | 3084 | } |
0793a61d | 3085 | } |
5b0311e1 FW |
3086 | } |
3087 | ||
3088 | static void | |
3089 | ctx_sched_in(struct perf_event_context *ctx, | |
3090 | struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
3091 | enum event_type_t event_type, |
3092 | struct task_struct *task) | |
5b0311e1 | 3093 | { |
db24d33e | 3094 | int is_active = ctx->is_active; |
c994d613 PZ |
3095 | u64 now; |
3096 | ||
3097 | lockdep_assert_held(&ctx->lock); | |
e5d1367f | 3098 | |
5b0311e1 | 3099 | if (likely(!ctx->nr_events)) |
facc4307 | 3100 | return; |
5b0311e1 | 3101 | |
3cbaa590 | 3102 | ctx->is_active |= (event_type | EVENT_TIME); |
63e30d3e PZ |
3103 | if (ctx->task) { |
3104 | if (!is_active) | |
3105 | cpuctx->task_ctx = ctx; | |
3106 | else | |
3107 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
3108 | } | |
3109 | ||
3cbaa590 PZ |
3110 | is_active ^= ctx->is_active; /* changed bits */ |
3111 | ||
3112 | if (is_active & EVENT_TIME) { | |
3113 | /* start ctx time */ | |
3114 | now = perf_clock(); | |
3115 | ctx->timestamp = now; | |
3116 | perf_cgroup_set_timestamp(task, ctx); | |
3117 | } | |
3118 | ||
5b0311e1 FW |
3119 | /* |
3120 | * First go through the list and put on any pinned groups | |
3121 | * in order to give them the best chance of going on. | |
3122 | */ | |
3cbaa590 | 3123 | if (is_active & EVENT_PINNED) |
6e37738a | 3124 | ctx_pinned_sched_in(ctx, cpuctx); |
5b0311e1 FW |
3125 | |
3126 | /* Then walk through the lower prio flexible groups */ | |
3cbaa590 | 3127 | if (is_active & EVENT_FLEXIBLE) |
6e37738a | 3128 | ctx_flexible_sched_in(ctx, cpuctx); |
235c7fc7 IM |
3129 | } |
3130 | ||
329c0e01 | 3131 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, |
e5d1367f SE |
3132 | enum event_type_t event_type, |
3133 | struct task_struct *task) | |
329c0e01 FW |
3134 | { |
3135 | struct perf_event_context *ctx = &cpuctx->ctx; | |
3136 | ||
e5d1367f | 3137 | ctx_sched_in(ctx, cpuctx, event_type, task); |
329c0e01 FW |
3138 | } |
3139 | ||
e5d1367f SE |
3140 | static void perf_event_context_sched_in(struct perf_event_context *ctx, |
3141 | struct task_struct *task) | |
235c7fc7 | 3142 | { |
108b02cf | 3143 | struct perf_cpu_context *cpuctx; |
235c7fc7 | 3144 | |
108b02cf | 3145 | cpuctx = __get_cpu_context(ctx); |
329c0e01 FW |
3146 | if (cpuctx->task_ctx == ctx) |
3147 | return; | |
3148 | ||
facc4307 | 3149 | perf_ctx_lock(cpuctx, ctx); |
fdccc3fb | 3150 | /* |
3151 | * We must check ctx->nr_events while holding ctx->lock, such | |
3152 | * that we serialize against perf_install_in_context(). | |
3153 | */ | |
3154 | if (!ctx->nr_events) | |
3155 | goto unlock; | |
3156 | ||
1b9a644f | 3157 | perf_pmu_disable(ctx->pmu); |
329c0e01 FW |
3158 | /* |
3159 | * We want to keep the following priority order: | |
3160 | * cpu pinned (that don't need to move), task pinned, | |
3161 | * cpu flexible, task flexible. | |
fe45bafb AS |
3162 | * |
3163 | * However, if task's ctx is not carrying any pinned | |
3164 | * events, no need to flip the cpuctx's events around. | |
329c0e01 | 3165 | */ |
fe45bafb AS |
3166 | if (!list_empty(&ctx->pinned_groups)) |
3167 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
63e30d3e | 3168 | perf_event_sched_in(cpuctx, ctx, task); |
facc4307 | 3169 | perf_pmu_enable(ctx->pmu); |
fdccc3fb | 3170 | |
3171 | unlock: | |
facc4307 | 3172 | perf_ctx_unlock(cpuctx, ctx); |
235c7fc7 IM |
3173 | } |
3174 | ||
8dc85d54 PZ |
3175 | /* |
3176 | * Called from scheduler to add the events of the current task | |
3177 | * with interrupts disabled. | |
3178 | * | |
3179 | * We restore the event value and then enable it. | |
3180 | * | |
3181 | * This does not protect us against NMI, but enable() | |
3182 | * sets the enabled bit in the control field of event _before_ | |
3183 | * accessing the event control register. If a NMI hits, then it will | |
3184 | * keep the event running. | |
3185 | */ | |
ab0cce56 JO |
3186 | void __perf_event_task_sched_in(struct task_struct *prev, |
3187 | struct task_struct *task) | |
8dc85d54 PZ |
3188 | { |
3189 | struct perf_event_context *ctx; | |
3190 | int ctxn; | |
3191 | ||
7e41d177 PZ |
3192 | /* |
3193 | * If cgroup events exist on this CPU, then we need to check if we have | |
3194 | * to switch in PMU state; cgroup event are system-wide mode only. | |
3195 | * | |
3196 | * Since cgroup events are CPU events, we must schedule these in before | |
3197 | * we schedule in the task events. | |
3198 | */ | |
3199 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) | |
3200 | perf_cgroup_sched_in(prev, task); | |
3201 | ||
8dc85d54 PZ |
3202 | for_each_task_context_nr(ctxn) { |
3203 | ctx = task->perf_event_ctxp[ctxn]; | |
3204 | if (likely(!ctx)) | |
3205 | continue; | |
3206 | ||
e5d1367f | 3207 | perf_event_context_sched_in(ctx, task); |
8dc85d54 | 3208 | } |
d010b332 | 3209 | |
45ac1403 AH |
3210 | if (atomic_read(&nr_switch_events)) |
3211 | perf_event_switch(task, prev, true); | |
3212 | ||
ba532500 YZ |
3213 | if (__this_cpu_read(perf_sched_cb_usages)) |
3214 | perf_pmu_sched_task(prev, task, true); | |
235c7fc7 IM |
3215 | } |
3216 | ||
abd50713 PZ |
3217 | static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count) |
3218 | { | |
3219 | u64 frequency = event->attr.sample_freq; | |
3220 | u64 sec = NSEC_PER_SEC; | |
3221 | u64 divisor, dividend; | |
3222 | ||
3223 | int count_fls, nsec_fls, frequency_fls, sec_fls; | |
3224 | ||
3225 | count_fls = fls64(count); | |
3226 | nsec_fls = fls64(nsec); | |
3227 | frequency_fls = fls64(frequency); | |
3228 | sec_fls = 30; | |
3229 | ||
3230 | /* | |
3231 | * We got @count in @nsec, with a target of sample_freq HZ | |
3232 | * the target period becomes: | |
3233 | * | |
3234 | * @count * 10^9 | |
3235 | * period = ------------------- | |
3236 | * @nsec * sample_freq | |
3237 | * | |
3238 | */ | |
3239 | ||
3240 | /* | |
3241 | * Reduce accuracy by one bit such that @a and @b converge | |
3242 | * to a similar magnitude. | |
3243 | */ | |
fe4b04fa | 3244 | #define REDUCE_FLS(a, b) \ |
abd50713 PZ |
3245 | do { \ |
3246 | if (a##_fls > b##_fls) { \ | |
3247 | a >>= 1; \ | |
3248 | a##_fls--; \ | |
3249 | } else { \ | |
3250 | b >>= 1; \ | |
3251 | b##_fls--; \ | |
3252 | } \ | |
3253 | } while (0) | |
3254 | ||
3255 | /* | |
3256 | * Reduce accuracy until either term fits in a u64, then proceed with | |
3257 | * the other, so that finally we can do a u64/u64 division. | |
3258 | */ | |
3259 | while (count_fls + sec_fls > 64 && nsec_fls + frequency_fls > 64) { | |
3260 | REDUCE_FLS(nsec, frequency); | |
3261 | REDUCE_FLS(sec, count); | |
3262 | } | |
3263 | ||
3264 | if (count_fls + sec_fls > 64) { | |
3265 | divisor = nsec * frequency; | |
3266 | ||
3267 | while (count_fls + sec_fls > 64) { | |
3268 | REDUCE_FLS(count, sec); | |
3269 | divisor >>= 1; | |
3270 | } | |
3271 | ||
3272 | dividend = count * sec; | |
3273 | } else { | |
3274 | dividend = count * sec; | |
3275 | ||
3276 | while (nsec_fls + frequency_fls > 64) { | |
3277 | REDUCE_FLS(nsec, frequency); | |
3278 | dividend >>= 1; | |
3279 | } | |
3280 | ||
3281 | divisor = nsec * frequency; | |
3282 | } | |
3283 | ||
f6ab91ad PZ |
3284 | if (!divisor) |
3285 | return dividend; | |
3286 | ||
abd50713 PZ |
3287 | return div64_u64(dividend, divisor); |
3288 | } | |
3289 | ||
e050e3f0 SE |
3290 | static DEFINE_PER_CPU(int, perf_throttled_count); |
3291 | static DEFINE_PER_CPU(u64, perf_throttled_seq); | |
3292 | ||
f39d47ff | 3293 | static void perf_adjust_period(struct perf_event *event, u64 nsec, u64 count, bool disable) |
bd2b5b12 | 3294 | { |
cdd6c482 | 3295 | struct hw_perf_event *hwc = &event->hw; |
f6ab91ad | 3296 | s64 period, sample_period; |
bd2b5b12 PZ |
3297 | s64 delta; |
3298 | ||
abd50713 | 3299 | period = perf_calculate_period(event, nsec, count); |
bd2b5b12 PZ |
3300 | |
3301 | delta = (s64)(period - hwc->sample_period); | |
3302 | delta = (delta + 7) / 8; /* low pass filter */ | |
3303 | ||
3304 | sample_period = hwc->sample_period + delta; | |
3305 | ||
3306 | if (!sample_period) | |
3307 | sample_period = 1; | |
3308 | ||
bd2b5b12 | 3309 | hwc->sample_period = sample_period; |
abd50713 | 3310 | |
e7850595 | 3311 | if (local64_read(&hwc->period_left) > 8*sample_period) { |
f39d47ff SE |
3312 | if (disable) |
3313 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3314 | ||
e7850595 | 3315 | local64_set(&hwc->period_left, 0); |
f39d47ff SE |
3316 | |
3317 | if (disable) | |
3318 | event->pmu->start(event, PERF_EF_RELOAD); | |
abd50713 | 3319 | } |
bd2b5b12 PZ |
3320 | } |
3321 | ||
e050e3f0 SE |
3322 | /* |
3323 | * combine freq adjustment with unthrottling to avoid two passes over the | |
3324 | * events. At the same time, make sure, having freq events does not change | |
3325 | * the rate of unthrottling as that would introduce bias. | |
3326 | */ | |
3327 | static void perf_adjust_freq_unthr_context(struct perf_event_context *ctx, | |
3328 | int needs_unthr) | |
60db5e09 | 3329 | { |
cdd6c482 IM |
3330 | struct perf_event *event; |
3331 | struct hw_perf_event *hwc; | |
e050e3f0 | 3332 | u64 now, period = TICK_NSEC; |
abd50713 | 3333 | s64 delta; |
60db5e09 | 3334 | |
e050e3f0 SE |
3335 | /* |
3336 | * only need to iterate over all events iff: | |
3337 | * - context have events in frequency mode (needs freq adjust) | |
3338 | * - there are events to unthrottle on this cpu | |
3339 | */ | |
3340 | if (!(ctx->nr_freq || needs_unthr)) | |
0f5a2601 PZ |
3341 | return; |
3342 | ||
e050e3f0 | 3343 | raw_spin_lock(&ctx->lock); |
f39d47ff | 3344 | perf_pmu_disable(ctx->pmu); |
e050e3f0 | 3345 | |
03541f8b | 3346 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { |
cdd6c482 | 3347 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
60db5e09 PZ |
3348 | continue; |
3349 | ||
5632ab12 | 3350 | if (!event_filter_match(event)) |
5d27c23d PZ |
3351 | continue; |
3352 | ||
44377277 AS |
3353 | perf_pmu_disable(event->pmu); |
3354 | ||
cdd6c482 | 3355 | hwc = &event->hw; |
6a24ed6c | 3356 | |
ae23bff1 | 3357 | if (hwc->interrupts == MAX_INTERRUPTS) { |
e050e3f0 | 3358 | hwc->interrupts = 0; |
cdd6c482 | 3359 | perf_log_throttle(event, 1); |
a4eaf7f1 | 3360 | event->pmu->start(event, 0); |
a78ac325 PZ |
3361 | } |
3362 | ||
cdd6c482 | 3363 | if (!event->attr.freq || !event->attr.sample_freq) |
44377277 | 3364 | goto next; |
60db5e09 | 3365 | |
e050e3f0 SE |
3366 | /* |
3367 | * stop the event and update event->count | |
3368 | */ | |
3369 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3370 | ||
e7850595 | 3371 | now = local64_read(&event->count); |
abd50713 PZ |
3372 | delta = now - hwc->freq_count_stamp; |
3373 | hwc->freq_count_stamp = now; | |
60db5e09 | 3374 | |
e050e3f0 SE |
3375 | /* |
3376 | * restart the event | |
3377 | * reload only if value has changed | |
f39d47ff SE |
3378 | * we have stopped the event so tell that |
3379 | * to perf_adjust_period() to avoid stopping it | |
3380 | * twice. | |
e050e3f0 | 3381 | */ |
abd50713 | 3382 | if (delta > 0) |
f39d47ff | 3383 | perf_adjust_period(event, period, delta, false); |
e050e3f0 SE |
3384 | |
3385 | event->pmu->start(event, delta > 0 ? PERF_EF_RELOAD : 0); | |
44377277 AS |
3386 | next: |
3387 | perf_pmu_enable(event->pmu); | |
60db5e09 | 3388 | } |
e050e3f0 | 3389 | |
f39d47ff | 3390 | perf_pmu_enable(ctx->pmu); |
e050e3f0 | 3391 | raw_spin_unlock(&ctx->lock); |
60db5e09 PZ |
3392 | } |
3393 | ||
235c7fc7 | 3394 | /* |
cdd6c482 | 3395 | * Round-robin a context's events: |
235c7fc7 | 3396 | */ |
cdd6c482 | 3397 | static void rotate_ctx(struct perf_event_context *ctx) |
0793a61d | 3398 | { |
dddd3379 TG |
3399 | /* |
3400 | * Rotate the first entry last of non-pinned groups. Rotation might be | |
3401 | * disabled by the inheritance code. | |
3402 | */ | |
3403 | if (!ctx->rotate_disable) | |
3404 | list_rotate_left(&ctx->flexible_groups); | |
235c7fc7 IM |
3405 | } |
3406 | ||
9e630205 | 3407 | static int perf_rotate_context(struct perf_cpu_context *cpuctx) |
235c7fc7 | 3408 | { |
8dc85d54 | 3409 | struct perf_event_context *ctx = NULL; |
2fde4f94 | 3410 | int rotate = 0; |
7fc23a53 | 3411 | |
b5ab4cd5 | 3412 | if (cpuctx->ctx.nr_events) { |
b5ab4cd5 PZ |
3413 | if (cpuctx->ctx.nr_events != cpuctx->ctx.nr_active) |
3414 | rotate = 1; | |
3415 | } | |
235c7fc7 | 3416 | |
8dc85d54 | 3417 | ctx = cpuctx->task_ctx; |
b5ab4cd5 | 3418 | if (ctx && ctx->nr_events) { |
b5ab4cd5 PZ |
3419 | if (ctx->nr_events != ctx->nr_active) |
3420 | rotate = 1; | |
3421 | } | |
9717e6cd | 3422 | |
e050e3f0 | 3423 | if (!rotate) |
0f5a2601 PZ |
3424 | goto done; |
3425 | ||
facc4307 | 3426 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
1b9a644f | 3427 | perf_pmu_disable(cpuctx->ctx.pmu); |
60db5e09 | 3428 | |
e050e3f0 SE |
3429 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); |
3430 | if (ctx) | |
3431 | ctx_sched_out(ctx, cpuctx, EVENT_FLEXIBLE); | |
0793a61d | 3432 | |
e050e3f0 SE |
3433 | rotate_ctx(&cpuctx->ctx); |
3434 | if (ctx) | |
3435 | rotate_ctx(ctx); | |
235c7fc7 | 3436 | |
e050e3f0 | 3437 | perf_event_sched_in(cpuctx, ctx, current); |
235c7fc7 | 3438 | |
0f5a2601 PZ |
3439 | perf_pmu_enable(cpuctx->ctx.pmu); |
3440 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
b5ab4cd5 | 3441 | done: |
9e630205 SE |
3442 | |
3443 | return rotate; | |
e9d2b064 PZ |
3444 | } |
3445 | ||
3446 | void perf_event_task_tick(void) | |
3447 | { | |
2fde4f94 MR |
3448 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
3449 | struct perf_event_context *ctx, *tmp; | |
e050e3f0 | 3450 | int throttled; |
b5ab4cd5 | 3451 | |
16444645 | 3452 | lockdep_assert_irqs_disabled(); |
e9d2b064 | 3453 | |
e050e3f0 SE |
3454 | __this_cpu_inc(perf_throttled_seq); |
3455 | throttled = __this_cpu_xchg(perf_throttled_count, 0); | |
555e0c1e | 3456 | tick_dep_clear_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
e050e3f0 | 3457 | |
2fde4f94 | 3458 | list_for_each_entry_safe(ctx, tmp, head, active_ctx_list) |
e050e3f0 | 3459 | perf_adjust_freq_unthr_context(ctx, throttled); |
0793a61d TG |
3460 | } |
3461 | ||
889ff015 FW |
3462 | static int event_enable_on_exec(struct perf_event *event, |
3463 | struct perf_event_context *ctx) | |
3464 | { | |
3465 | if (!event->attr.enable_on_exec) | |
3466 | return 0; | |
3467 | ||
3468 | event->attr.enable_on_exec = 0; | |
3469 | if (event->state >= PERF_EVENT_STATE_INACTIVE) | |
3470 | return 0; | |
3471 | ||
0d3d73aa | 3472 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
889ff015 FW |
3473 | |
3474 | return 1; | |
3475 | } | |
3476 | ||
57e7986e | 3477 | /* |
cdd6c482 | 3478 | * Enable all of a task's events that have been marked enable-on-exec. |
57e7986e PM |
3479 | * This expects task == current. |
3480 | */ | |
c1274499 | 3481 | static void perf_event_enable_on_exec(int ctxn) |
57e7986e | 3482 | { |
c1274499 | 3483 | struct perf_event_context *ctx, *clone_ctx = NULL; |
487f05e1 | 3484 | enum event_type_t event_type = 0; |
3e349507 | 3485 | struct perf_cpu_context *cpuctx; |
cdd6c482 | 3486 | struct perf_event *event; |
57e7986e PM |
3487 | unsigned long flags; |
3488 | int enabled = 0; | |
3489 | ||
3490 | local_irq_save(flags); | |
c1274499 | 3491 | ctx = current->perf_event_ctxp[ctxn]; |
cdd6c482 | 3492 | if (!ctx || !ctx->nr_events) |
57e7986e PM |
3493 | goto out; |
3494 | ||
3e349507 PZ |
3495 | cpuctx = __get_cpu_context(ctx); |
3496 | perf_ctx_lock(cpuctx, ctx); | |
7fce2509 | 3497 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
487f05e1 | 3498 | list_for_each_entry(event, &ctx->event_list, event_entry) { |
3e349507 | 3499 | enabled |= event_enable_on_exec(event, ctx); |
487f05e1 AS |
3500 | event_type |= get_event_type(event); |
3501 | } | |
57e7986e PM |
3502 | |
3503 | /* | |
3e349507 | 3504 | * Unclone and reschedule this context if we enabled any event. |
57e7986e | 3505 | */ |
3e349507 | 3506 | if (enabled) { |
211de6eb | 3507 | clone_ctx = unclone_ctx(ctx); |
487f05e1 | 3508 | ctx_resched(cpuctx, ctx, event_type); |
7bbba0eb PZ |
3509 | } else { |
3510 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
3e349507 PZ |
3511 | } |
3512 | perf_ctx_unlock(cpuctx, ctx); | |
57e7986e | 3513 | |
9ed6060d | 3514 | out: |
57e7986e | 3515 | local_irq_restore(flags); |
211de6eb PZ |
3516 | |
3517 | if (clone_ctx) | |
3518 | put_ctx(clone_ctx); | |
57e7986e PM |
3519 | } |
3520 | ||
0492d4c5 PZ |
3521 | struct perf_read_data { |
3522 | struct perf_event *event; | |
3523 | bool group; | |
7d88962e | 3524 | int ret; |
0492d4c5 PZ |
3525 | }; |
3526 | ||
451d24d1 | 3527 | static int __perf_event_read_cpu(struct perf_event *event, int event_cpu) |
d6a2f903 | 3528 | { |
d6a2f903 DCC |
3529 | u16 local_pkg, event_pkg; |
3530 | ||
3531 | if (event->group_caps & PERF_EV_CAP_READ_ACTIVE_PKG) { | |
451d24d1 PZ |
3532 | int local_cpu = smp_processor_id(); |
3533 | ||
3534 | event_pkg = topology_physical_package_id(event_cpu); | |
3535 | local_pkg = topology_physical_package_id(local_cpu); | |
d6a2f903 DCC |
3536 | |
3537 | if (event_pkg == local_pkg) | |
3538 | return local_cpu; | |
3539 | } | |
3540 | ||
3541 | return event_cpu; | |
3542 | } | |
3543 | ||
0793a61d | 3544 | /* |
cdd6c482 | 3545 | * Cross CPU call to read the hardware event |
0793a61d | 3546 | */ |
cdd6c482 | 3547 | static void __perf_event_read(void *info) |
0793a61d | 3548 | { |
0492d4c5 PZ |
3549 | struct perf_read_data *data = info; |
3550 | struct perf_event *sub, *event = data->event; | |
cdd6c482 | 3551 | struct perf_event_context *ctx = event->ctx; |
108b02cf | 3552 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
4a00c16e | 3553 | struct pmu *pmu = event->pmu; |
621a01ea | 3554 | |
e1ac3614 PM |
3555 | /* |
3556 | * If this is a task context, we need to check whether it is | |
3557 | * the current task context of this cpu. If not it has been | |
3558 | * scheduled out before the smp call arrived. In that case | |
cdd6c482 IM |
3559 | * event->count would have been updated to a recent sample |
3560 | * when the event was scheduled out. | |
e1ac3614 PM |
3561 | */ |
3562 | if (ctx->task && cpuctx->task_ctx != ctx) | |
3563 | return; | |
3564 | ||
e625cce1 | 3565 | raw_spin_lock(&ctx->lock); |
0c1cbc18 | 3566 | if (ctx->is_active & EVENT_TIME) { |
542e72fc | 3567 | update_context_time(ctx); |
e5d1367f SE |
3568 | update_cgrp_time_from_event(event); |
3569 | } | |
0492d4c5 | 3570 | |
0d3d73aa PZ |
3571 | perf_event_update_time(event); |
3572 | if (data->group) | |
3573 | perf_event_update_sibling_time(event); | |
0c1cbc18 | 3574 | |
4a00c16e SB |
3575 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
3576 | goto unlock; | |
0492d4c5 | 3577 | |
4a00c16e SB |
3578 | if (!data->group) { |
3579 | pmu->read(event); | |
3580 | data->ret = 0; | |
0492d4c5 | 3581 | goto unlock; |
4a00c16e SB |
3582 | } |
3583 | ||
3584 | pmu->start_txn(pmu, PERF_PMU_TXN_READ); | |
3585 | ||
3586 | pmu->read(event); | |
0492d4c5 PZ |
3587 | |
3588 | list_for_each_entry(sub, &event->sibling_list, group_entry) { | |
4a00c16e SB |
3589 | if (sub->state == PERF_EVENT_STATE_ACTIVE) { |
3590 | /* | |
3591 | * Use sibling's PMU rather than @event's since | |
3592 | * sibling could be on different (eg: software) PMU. | |
3593 | */ | |
0492d4c5 | 3594 | sub->pmu->read(sub); |
4a00c16e | 3595 | } |
0492d4c5 | 3596 | } |
4a00c16e SB |
3597 | |
3598 | data->ret = pmu->commit_txn(pmu); | |
0492d4c5 PZ |
3599 | |
3600 | unlock: | |
e625cce1 | 3601 | raw_spin_unlock(&ctx->lock); |
0793a61d TG |
3602 | } |
3603 | ||
b5e58793 PZ |
3604 | static inline u64 perf_event_count(struct perf_event *event) |
3605 | { | |
c39a0e2c | 3606 | return local64_read(&event->count) + atomic64_read(&event->child_count); |
b5e58793 PZ |
3607 | } |
3608 | ||
ffe8690c KX |
3609 | /* |
3610 | * NMI-safe method to read a local event, that is an event that | |
3611 | * is: | |
3612 | * - either for the current task, or for this CPU | |
3613 | * - does not have inherit set, for inherited task events | |
3614 | * will not be local and we cannot read them atomically | |
3615 | * - must not have a pmu::count method | |
3616 | */ | |
7d9285e8 YS |
3617 | int perf_event_read_local(struct perf_event *event, u64 *value, |
3618 | u64 *enabled, u64 *running) | |
ffe8690c KX |
3619 | { |
3620 | unsigned long flags; | |
f91840a3 | 3621 | int ret = 0; |
ffe8690c KX |
3622 | |
3623 | /* | |
3624 | * Disabling interrupts avoids all counter scheduling (context | |
3625 | * switches, timer based rotation and IPIs). | |
3626 | */ | |
3627 | local_irq_save(flags); | |
3628 | ||
ffe8690c KX |
3629 | /* |
3630 | * It must not be an event with inherit set, we cannot read | |
3631 | * all child counters from atomic context. | |
3632 | */ | |
f91840a3 AS |
3633 | if (event->attr.inherit) { |
3634 | ret = -EOPNOTSUPP; | |
3635 | goto out; | |
3636 | } | |
ffe8690c | 3637 | |
f91840a3 AS |
3638 | /* If this is a per-task event, it must be for current */ |
3639 | if ((event->attach_state & PERF_ATTACH_TASK) && | |
3640 | event->hw.target != current) { | |
3641 | ret = -EINVAL; | |
3642 | goto out; | |
3643 | } | |
3644 | ||
3645 | /* If this is a per-CPU event, it must be for this CPU */ | |
3646 | if (!(event->attach_state & PERF_ATTACH_TASK) && | |
3647 | event->cpu != smp_processor_id()) { | |
3648 | ret = -EINVAL; | |
3649 | goto out; | |
3650 | } | |
ffe8690c | 3651 | |
7c02c600 RC |
3652 | /* If this is a pinned event it must be running on this CPU */ |
3653 | if (event->attr.pinned && event->oncpu != smp_processor_id()) { | |
3654 | ret = -EBUSY; | |
3655 | goto out; | |
3656 | } | |
3657 | ||
ffe8690c KX |
3658 | /* |
3659 | * If the event is currently on this CPU, its either a per-task event, | |
3660 | * or local to this CPU. Furthermore it means its ACTIVE (otherwise | |
3661 | * oncpu == -1). | |
3662 | */ | |
3663 | if (event->oncpu == smp_processor_id()) | |
3664 | event->pmu->read(event); | |
3665 | ||
f91840a3 | 3666 | *value = local64_read(&event->count); |
0d3d73aa PZ |
3667 | if (enabled || running) { |
3668 | u64 now = event->shadow_ctx_time + perf_clock(); | |
3669 | u64 __enabled, __running; | |
3670 | ||
3671 | __perf_update_times(event, now, &__enabled, &__running); | |
3672 | if (enabled) | |
3673 | *enabled = __enabled; | |
3674 | if (running) | |
3675 | *running = __running; | |
3676 | } | |
f91840a3 | 3677 | out: |
ffe8690c KX |
3678 | local_irq_restore(flags); |
3679 | ||
f91840a3 | 3680 | return ret; |
ffe8690c KX |
3681 | } |
3682 | ||
7d88962e | 3683 | static int perf_event_read(struct perf_event *event, bool group) |
0793a61d | 3684 | { |
0c1cbc18 | 3685 | enum perf_event_state state = READ_ONCE(event->state); |
451d24d1 | 3686 | int event_cpu, ret = 0; |
7d88962e | 3687 | |
0793a61d | 3688 | /* |
cdd6c482 IM |
3689 | * If event is enabled and currently active on a CPU, update the |
3690 | * value in the event structure: | |
0793a61d | 3691 | */ |
0c1cbc18 PZ |
3692 | again: |
3693 | if (state == PERF_EVENT_STATE_ACTIVE) { | |
3694 | struct perf_read_data data; | |
3695 | ||
3696 | /* | |
3697 | * Orders the ->state and ->oncpu loads such that if we see | |
3698 | * ACTIVE we must also see the right ->oncpu. | |
3699 | * | |
3700 | * Matches the smp_wmb() from event_sched_in(). | |
3701 | */ | |
3702 | smp_rmb(); | |
d6a2f903 | 3703 | |
451d24d1 PZ |
3704 | event_cpu = READ_ONCE(event->oncpu); |
3705 | if ((unsigned)event_cpu >= nr_cpu_ids) | |
3706 | return 0; | |
3707 | ||
0c1cbc18 PZ |
3708 | data = (struct perf_read_data){ |
3709 | .event = event, | |
3710 | .group = group, | |
3711 | .ret = 0, | |
3712 | }; | |
3713 | ||
451d24d1 PZ |
3714 | preempt_disable(); |
3715 | event_cpu = __perf_event_read_cpu(event, event_cpu); | |
d6a2f903 | 3716 | |
58763148 PZ |
3717 | /* |
3718 | * Purposely ignore the smp_call_function_single() return | |
3719 | * value. | |
3720 | * | |
451d24d1 | 3721 | * If event_cpu isn't a valid CPU it means the event got |
58763148 PZ |
3722 | * scheduled out and that will have updated the event count. |
3723 | * | |
3724 | * Therefore, either way, we'll have an up-to-date event count | |
3725 | * after this. | |
3726 | */ | |
451d24d1 PZ |
3727 | (void)smp_call_function_single(event_cpu, __perf_event_read, &data, 1); |
3728 | preempt_enable(); | |
58763148 | 3729 | ret = data.ret; |
0c1cbc18 PZ |
3730 | |
3731 | } else if (state == PERF_EVENT_STATE_INACTIVE) { | |
2b8988c9 PZ |
3732 | struct perf_event_context *ctx = event->ctx; |
3733 | unsigned long flags; | |
3734 | ||
e625cce1 | 3735 | raw_spin_lock_irqsave(&ctx->lock, flags); |
0c1cbc18 PZ |
3736 | state = event->state; |
3737 | if (state != PERF_EVENT_STATE_INACTIVE) { | |
3738 | raw_spin_unlock_irqrestore(&ctx->lock, flags); | |
3739 | goto again; | |
3740 | } | |
3741 | ||
c530ccd9 | 3742 | /* |
0c1cbc18 PZ |
3743 | * May read while context is not active (e.g., thread is |
3744 | * blocked), in that case we cannot update context time | |
c530ccd9 | 3745 | */ |
0c1cbc18 | 3746 | if (ctx->is_active & EVENT_TIME) { |
c530ccd9 | 3747 | update_context_time(ctx); |
e5d1367f SE |
3748 | update_cgrp_time_from_event(event); |
3749 | } | |
0c1cbc18 | 3750 | |
0d3d73aa | 3751 | perf_event_update_time(event); |
0492d4c5 | 3752 | if (group) |
0d3d73aa | 3753 | perf_event_update_sibling_time(event); |
e625cce1 | 3754 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
0793a61d | 3755 | } |
7d88962e SB |
3756 | |
3757 | return ret; | |
0793a61d TG |
3758 | } |
3759 | ||
a63eaf34 | 3760 | /* |
cdd6c482 | 3761 | * Initialize the perf_event context in a task_struct: |
a63eaf34 | 3762 | */ |
eb184479 | 3763 | static void __perf_event_init_context(struct perf_event_context *ctx) |
a63eaf34 | 3764 | { |
e625cce1 | 3765 | raw_spin_lock_init(&ctx->lock); |
a63eaf34 | 3766 | mutex_init(&ctx->mutex); |
2fde4f94 | 3767 | INIT_LIST_HEAD(&ctx->active_ctx_list); |
889ff015 FW |
3768 | INIT_LIST_HEAD(&ctx->pinned_groups); |
3769 | INIT_LIST_HEAD(&ctx->flexible_groups); | |
a63eaf34 PM |
3770 | INIT_LIST_HEAD(&ctx->event_list); |
3771 | atomic_set(&ctx->refcount, 1); | |
eb184479 PZ |
3772 | } |
3773 | ||
3774 | static struct perf_event_context * | |
3775 | alloc_perf_context(struct pmu *pmu, struct task_struct *task) | |
3776 | { | |
3777 | struct perf_event_context *ctx; | |
3778 | ||
3779 | ctx = kzalloc(sizeof(struct perf_event_context), GFP_KERNEL); | |
3780 | if (!ctx) | |
3781 | return NULL; | |
3782 | ||
3783 | __perf_event_init_context(ctx); | |
3784 | if (task) { | |
3785 | ctx->task = task; | |
3786 | get_task_struct(task); | |
0793a61d | 3787 | } |
eb184479 PZ |
3788 | ctx->pmu = pmu; |
3789 | ||
3790 | return ctx; | |
a63eaf34 PM |
3791 | } |
3792 | ||
2ebd4ffb MH |
3793 | static struct task_struct * |
3794 | find_lively_task_by_vpid(pid_t vpid) | |
3795 | { | |
3796 | struct task_struct *task; | |
0793a61d TG |
3797 | |
3798 | rcu_read_lock(); | |
2ebd4ffb | 3799 | if (!vpid) |
0793a61d TG |
3800 | task = current; |
3801 | else | |
2ebd4ffb | 3802 | task = find_task_by_vpid(vpid); |
0793a61d TG |
3803 | if (task) |
3804 | get_task_struct(task); | |
3805 | rcu_read_unlock(); | |
3806 | ||
3807 | if (!task) | |
3808 | return ERR_PTR(-ESRCH); | |
3809 | ||
2ebd4ffb | 3810 | return task; |
2ebd4ffb MH |
3811 | } |
3812 | ||
fe4b04fa PZ |
3813 | /* |
3814 | * Returns a matching context with refcount and pincount. | |
3815 | */ | |
108b02cf | 3816 | static struct perf_event_context * |
4af57ef2 YZ |
3817 | find_get_context(struct pmu *pmu, struct task_struct *task, |
3818 | struct perf_event *event) | |
0793a61d | 3819 | { |
211de6eb | 3820 | struct perf_event_context *ctx, *clone_ctx = NULL; |
22a4f650 | 3821 | struct perf_cpu_context *cpuctx; |
4af57ef2 | 3822 | void *task_ctx_data = NULL; |
25346b93 | 3823 | unsigned long flags; |
8dc85d54 | 3824 | int ctxn, err; |
4af57ef2 | 3825 | int cpu = event->cpu; |
0793a61d | 3826 | |
22a4ec72 | 3827 | if (!task) { |
cdd6c482 | 3828 | /* Must be root to operate on a CPU event: */ |
0764771d | 3829 | if (perf_paranoid_cpu() && !capable(CAP_SYS_ADMIN)) |
0793a61d TG |
3830 | return ERR_PTR(-EACCES); |
3831 | ||
108b02cf | 3832 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); |
0793a61d | 3833 | ctx = &cpuctx->ctx; |
c93f7669 | 3834 | get_ctx(ctx); |
fe4b04fa | 3835 | ++ctx->pin_count; |
0793a61d | 3836 | |
0793a61d TG |
3837 | return ctx; |
3838 | } | |
3839 | ||
8dc85d54 PZ |
3840 | err = -EINVAL; |
3841 | ctxn = pmu->task_ctx_nr; | |
3842 | if (ctxn < 0) | |
3843 | goto errout; | |
3844 | ||
4af57ef2 YZ |
3845 | if (event->attach_state & PERF_ATTACH_TASK_DATA) { |
3846 | task_ctx_data = kzalloc(pmu->task_ctx_size, GFP_KERNEL); | |
3847 | if (!task_ctx_data) { | |
3848 | err = -ENOMEM; | |
3849 | goto errout; | |
3850 | } | |
3851 | } | |
3852 | ||
9ed6060d | 3853 | retry: |
8dc85d54 | 3854 | ctx = perf_lock_task_context(task, ctxn, &flags); |
c93f7669 | 3855 | if (ctx) { |
211de6eb | 3856 | clone_ctx = unclone_ctx(ctx); |
fe4b04fa | 3857 | ++ctx->pin_count; |
4af57ef2 YZ |
3858 | |
3859 | if (task_ctx_data && !ctx->task_ctx_data) { | |
3860 | ctx->task_ctx_data = task_ctx_data; | |
3861 | task_ctx_data = NULL; | |
3862 | } | |
e625cce1 | 3863 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
211de6eb PZ |
3864 | |
3865 | if (clone_ctx) | |
3866 | put_ctx(clone_ctx); | |
9137fb28 | 3867 | } else { |
eb184479 | 3868 | ctx = alloc_perf_context(pmu, task); |
c93f7669 PM |
3869 | err = -ENOMEM; |
3870 | if (!ctx) | |
3871 | goto errout; | |
eb184479 | 3872 | |
4af57ef2 YZ |
3873 | if (task_ctx_data) { |
3874 | ctx->task_ctx_data = task_ctx_data; | |
3875 | task_ctx_data = NULL; | |
3876 | } | |
3877 | ||
dbe08d82 ON |
3878 | err = 0; |
3879 | mutex_lock(&task->perf_event_mutex); | |
3880 | /* | |
3881 | * If it has already passed perf_event_exit_task(). | |
3882 | * we must see PF_EXITING, it takes this mutex too. | |
3883 | */ | |
3884 | if (task->flags & PF_EXITING) | |
3885 | err = -ESRCH; | |
3886 | else if (task->perf_event_ctxp[ctxn]) | |
3887 | err = -EAGAIN; | |
fe4b04fa | 3888 | else { |
9137fb28 | 3889 | get_ctx(ctx); |
fe4b04fa | 3890 | ++ctx->pin_count; |
dbe08d82 | 3891 | rcu_assign_pointer(task->perf_event_ctxp[ctxn], ctx); |
fe4b04fa | 3892 | } |
dbe08d82 ON |
3893 | mutex_unlock(&task->perf_event_mutex); |
3894 | ||
3895 | if (unlikely(err)) { | |
9137fb28 | 3896 | put_ctx(ctx); |
dbe08d82 ON |
3897 | |
3898 | if (err == -EAGAIN) | |
3899 | goto retry; | |
3900 | goto errout; | |
a63eaf34 PM |
3901 | } |
3902 | } | |
3903 | ||
4af57ef2 | 3904 | kfree(task_ctx_data); |
0793a61d | 3905 | return ctx; |
c93f7669 | 3906 | |
9ed6060d | 3907 | errout: |
4af57ef2 | 3908 | kfree(task_ctx_data); |
c93f7669 | 3909 | return ERR_PTR(err); |
0793a61d TG |
3910 | } |
3911 | ||
6fb2915d | 3912 | static void perf_event_free_filter(struct perf_event *event); |
2541517c | 3913 | static void perf_event_free_bpf_prog(struct perf_event *event); |
6fb2915d | 3914 | |
cdd6c482 | 3915 | static void free_event_rcu(struct rcu_head *head) |
592903cd | 3916 | { |
cdd6c482 | 3917 | struct perf_event *event; |
592903cd | 3918 | |
cdd6c482 IM |
3919 | event = container_of(head, struct perf_event, rcu_head); |
3920 | if (event->ns) | |
3921 | put_pid_ns(event->ns); | |
6fb2915d | 3922 | perf_event_free_filter(event); |
cdd6c482 | 3923 | kfree(event); |
592903cd PZ |
3924 | } |
3925 | ||
b69cf536 PZ |
3926 | static void ring_buffer_attach(struct perf_event *event, |
3927 | struct ring_buffer *rb); | |
925d519a | 3928 | |
f2fb6bef KL |
3929 | static void detach_sb_event(struct perf_event *event) |
3930 | { | |
3931 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
3932 | ||
3933 | raw_spin_lock(&pel->lock); | |
3934 | list_del_rcu(&event->sb_list); | |
3935 | raw_spin_unlock(&pel->lock); | |
3936 | } | |
3937 | ||
a4f144eb | 3938 | static bool is_sb_event(struct perf_event *event) |
f2fb6bef | 3939 | { |
a4f144eb DCC |
3940 | struct perf_event_attr *attr = &event->attr; |
3941 | ||
f2fb6bef | 3942 | if (event->parent) |
a4f144eb | 3943 | return false; |
f2fb6bef KL |
3944 | |
3945 | if (event->attach_state & PERF_ATTACH_TASK) | |
a4f144eb | 3946 | return false; |
f2fb6bef | 3947 | |
a4f144eb DCC |
3948 | if (attr->mmap || attr->mmap_data || attr->mmap2 || |
3949 | attr->comm || attr->comm_exec || | |
3950 | attr->task || | |
3951 | attr->context_switch) | |
3952 | return true; | |
3953 | return false; | |
3954 | } | |
3955 | ||
3956 | static void unaccount_pmu_sb_event(struct perf_event *event) | |
3957 | { | |
3958 | if (is_sb_event(event)) | |
3959 | detach_sb_event(event); | |
f2fb6bef KL |
3960 | } |
3961 | ||
4beb31f3 | 3962 | static void unaccount_event_cpu(struct perf_event *event, int cpu) |
f1600952 | 3963 | { |
4beb31f3 FW |
3964 | if (event->parent) |
3965 | return; | |
3966 | ||
4beb31f3 FW |
3967 | if (is_cgroup_event(event)) |
3968 | atomic_dec(&per_cpu(perf_cgroup_events, cpu)); | |
3969 | } | |
925d519a | 3970 | |
555e0c1e FW |
3971 | #ifdef CONFIG_NO_HZ_FULL |
3972 | static DEFINE_SPINLOCK(nr_freq_lock); | |
3973 | #endif | |
3974 | ||
3975 | static void unaccount_freq_event_nohz(void) | |
3976 | { | |
3977 | #ifdef CONFIG_NO_HZ_FULL | |
3978 | spin_lock(&nr_freq_lock); | |
3979 | if (atomic_dec_and_test(&nr_freq_events)) | |
3980 | tick_nohz_dep_clear(TICK_DEP_BIT_PERF_EVENTS); | |
3981 | spin_unlock(&nr_freq_lock); | |
3982 | #endif | |
3983 | } | |
3984 | ||
3985 | static void unaccount_freq_event(void) | |
3986 | { | |
3987 | if (tick_nohz_full_enabled()) | |
3988 | unaccount_freq_event_nohz(); | |
3989 | else | |
3990 | atomic_dec(&nr_freq_events); | |
3991 | } | |
3992 | ||
4beb31f3 FW |
3993 | static void unaccount_event(struct perf_event *event) |
3994 | { | |
25432ae9 PZ |
3995 | bool dec = false; |
3996 | ||
4beb31f3 FW |
3997 | if (event->parent) |
3998 | return; | |
3999 | ||
4000 | if (event->attach_state & PERF_ATTACH_TASK) | |
25432ae9 | 4001 | dec = true; |
4beb31f3 FW |
4002 | if (event->attr.mmap || event->attr.mmap_data) |
4003 | atomic_dec(&nr_mmap_events); | |
4004 | if (event->attr.comm) | |
4005 | atomic_dec(&nr_comm_events); | |
e4222673 HB |
4006 | if (event->attr.namespaces) |
4007 | atomic_dec(&nr_namespaces_events); | |
4beb31f3 FW |
4008 | if (event->attr.task) |
4009 | atomic_dec(&nr_task_events); | |
948b26b6 | 4010 | if (event->attr.freq) |
555e0c1e | 4011 | unaccount_freq_event(); |
45ac1403 | 4012 | if (event->attr.context_switch) { |
25432ae9 | 4013 | dec = true; |
45ac1403 AH |
4014 | atomic_dec(&nr_switch_events); |
4015 | } | |
4beb31f3 | 4016 | if (is_cgroup_event(event)) |
25432ae9 | 4017 | dec = true; |
4beb31f3 | 4018 | if (has_branch_stack(event)) |
25432ae9 PZ |
4019 | dec = true; |
4020 | ||
9107c89e PZ |
4021 | if (dec) { |
4022 | if (!atomic_add_unless(&perf_sched_count, -1, 1)) | |
4023 | schedule_delayed_work(&perf_sched_work, HZ); | |
4024 | } | |
4beb31f3 FW |
4025 | |
4026 | unaccount_event_cpu(event, event->cpu); | |
f2fb6bef KL |
4027 | |
4028 | unaccount_pmu_sb_event(event); | |
4beb31f3 | 4029 | } |
925d519a | 4030 | |
9107c89e PZ |
4031 | static void perf_sched_delayed(struct work_struct *work) |
4032 | { | |
4033 | mutex_lock(&perf_sched_mutex); | |
4034 | if (atomic_dec_and_test(&perf_sched_count)) | |
4035 | static_branch_disable(&perf_sched_events); | |
4036 | mutex_unlock(&perf_sched_mutex); | |
4037 | } | |
4038 | ||
bed5b25a AS |
4039 | /* |
4040 | * The following implement mutual exclusion of events on "exclusive" pmus | |
4041 | * (PERF_PMU_CAP_EXCLUSIVE). Such pmus can only have one event scheduled | |
4042 | * at a time, so we disallow creating events that might conflict, namely: | |
4043 | * | |
4044 | * 1) cpu-wide events in the presence of per-task events, | |
4045 | * 2) per-task events in the presence of cpu-wide events, | |
4046 | * 3) two matching events on the same context. | |
4047 | * | |
4048 | * The former two cases are handled in the allocation path (perf_event_alloc(), | |
a0733e69 | 4049 | * _free_event()), the latter -- before the first perf_install_in_context(). |
bed5b25a AS |
4050 | */ |
4051 | static int exclusive_event_init(struct perf_event *event) | |
4052 | { | |
4053 | struct pmu *pmu = event->pmu; | |
4054 | ||
4055 | if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE)) | |
4056 | return 0; | |
4057 | ||
4058 | /* | |
4059 | * Prevent co-existence of per-task and cpu-wide events on the | |
4060 | * same exclusive pmu. | |
4061 | * | |
4062 | * Negative pmu::exclusive_cnt means there are cpu-wide | |
4063 | * events on this "exclusive" pmu, positive means there are | |
4064 | * per-task events. | |
4065 | * | |
4066 | * Since this is called in perf_event_alloc() path, event::ctx | |
4067 | * doesn't exist yet; it is, however, safe to use PERF_ATTACH_TASK | |
4068 | * to mean "per-task event", because unlike other attach states it | |
4069 | * never gets cleared. | |
4070 | */ | |
4071 | if (event->attach_state & PERF_ATTACH_TASK) { | |
4072 | if (!atomic_inc_unless_negative(&pmu->exclusive_cnt)) | |
4073 | return -EBUSY; | |
4074 | } else { | |
4075 | if (!atomic_dec_unless_positive(&pmu->exclusive_cnt)) | |
4076 | return -EBUSY; | |
4077 | } | |
4078 | ||
4079 | return 0; | |
4080 | } | |
4081 | ||
4082 | static void exclusive_event_destroy(struct perf_event *event) | |
4083 | { | |
4084 | struct pmu *pmu = event->pmu; | |
4085 | ||
4086 | if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE)) | |
4087 | return; | |
4088 | ||
4089 | /* see comment in exclusive_event_init() */ | |
4090 | if (event->attach_state & PERF_ATTACH_TASK) | |
4091 | atomic_dec(&pmu->exclusive_cnt); | |
4092 | else | |
4093 | atomic_inc(&pmu->exclusive_cnt); | |
4094 | } | |
4095 | ||
4096 | static bool exclusive_event_match(struct perf_event *e1, struct perf_event *e2) | |
4097 | { | |
3bf6215a | 4098 | if ((e1->pmu == e2->pmu) && |
bed5b25a AS |
4099 | (e1->cpu == e2->cpu || |
4100 | e1->cpu == -1 || | |
4101 | e2->cpu == -1)) | |
4102 | return true; | |
4103 | return false; | |
4104 | } | |
4105 | ||
4106 | /* Called under the same ctx::mutex as perf_install_in_context() */ | |
4107 | static bool exclusive_event_installable(struct perf_event *event, | |
4108 | struct perf_event_context *ctx) | |
4109 | { | |
4110 | struct perf_event *iter_event; | |
4111 | struct pmu *pmu = event->pmu; | |
4112 | ||
4113 | if (!(pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE)) | |
4114 | return true; | |
4115 | ||
4116 | list_for_each_entry(iter_event, &ctx->event_list, event_entry) { | |
4117 | if (exclusive_event_match(iter_event, event)) | |
4118 | return false; | |
4119 | } | |
4120 | ||
4121 | return true; | |
4122 | } | |
4123 | ||
375637bc AS |
4124 | static void perf_addr_filters_splice(struct perf_event *event, |
4125 | struct list_head *head); | |
4126 | ||
683ede43 | 4127 | static void _free_event(struct perf_event *event) |
f1600952 | 4128 | { |
e360adbe | 4129 | irq_work_sync(&event->pending); |
925d519a | 4130 | |
4beb31f3 | 4131 | unaccount_event(event); |
9ee318a7 | 4132 | |
76369139 | 4133 | if (event->rb) { |
9bb5d40c PZ |
4134 | /* |
4135 | * Can happen when we close an event with re-directed output. | |
4136 | * | |
4137 | * Since we have a 0 refcount, perf_mmap_close() will skip | |
4138 | * over us; possibly making our ring_buffer_put() the last. | |
4139 | */ | |
4140 | mutex_lock(&event->mmap_mutex); | |
b69cf536 | 4141 | ring_buffer_attach(event, NULL); |
9bb5d40c | 4142 | mutex_unlock(&event->mmap_mutex); |
a4be7c27 PZ |
4143 | } |
4144 | ||
e5d1367f SE |
4145 | if (is_cgroup_event(event)) |
4146 | perf_detach_cgroup(event); | |
4147 | ||
a0733e69 PZ |
4148 | if (!event->parent) { |
4149 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) | |
4150 | put_callchain_buffers(); | |
4151 | } | |
4152 | ||
4153 | perf_event_free_bpf_prog(event); | |
375637bc AS |
4154 | perf_addr_filters_splice(event, NULL); |
4155 | kfree(event->addr_filters_offs); | |
a0733e69 PZ |
4156 | |
4157 | if (event->destroy) | |
4158 | event->destroy(event); | |
4159 | ||
4160 | if (event->ctx) | |
4161 | put_ctx(event->ctx); | |
4162 | ||
ae162419 PB |
4163 | if (event->hw.target) |
4164 | put_task_struct(event->hw.target); | |
4165 | ||
62a92c8f AS |
4166 | exclusive_event_destroy(event); |
4167 | module_put(event->pmu->module); | |
a0733e69 PZ |
4168 | |
4169 | call_rcu(&event->rcu_head, free_event_rcu); | |
f1600952 PZ |
4170 | } |
4171 | ||
683ede43 PZ |
4172 | /* |
4173 | * Used to free events which have a known refcount of 1, such as in error paths | |
4174 | * where the event isn't exposed yet and inherited events. | |
4175 | */ | |
4176 | static void free_event(struct perf_event *event) | |
0793a61d | 4177 | { |
683ede43 PZ |
4178 | if (WARN(atomic_long_cmpxchg(&event->refcount, 1, 0) != 1, |
4179 | "unexpected event refcount: %ld; ptr=%p\n", | |
4180 | atomic_long_read(&event->refcount), event)) { | |
4181 | /* leak to avoid use-after-free */ | |
4182 | return; | |
4183 | } | |
0793a61d | 4184 | |
683ede43 | 4185 | _free_event(event); |
0793a61d TG |
4186 | } |
4187 | ||
a66a3052 | 4188 | /* |
f8697762 | 4189 | * Remove user event from the owner task. |
a66a3052 | 4190 | */ |
f8697762 | 4191 | static void perf_remove_from_owner(struct perf_event *event) |
fb0459d7 | 4192 | { |
8882135b | 4193 | struct task_struct *owner; |
fb0459d7 | 4194 | |
8882135b | 4195 | rcu_read_lock(); |
8882135b | 4196 | /* |
f47c02c0 PZ |
4197 | * Matches the smp_store_release() in perf_event_exit_task(). If we |
4198 | * observe !owner it means the list deletion is complete and we can | |
4199 | * indeed free this event, otherwise we need to serialize on | |
8882135b PZ |
4200 | * owner->perf_event_mutex. |
4201 | */ | |
506458ef | 4202 | owner = READ_ONCE(event->owner); |
8882135b PZ |
4203 | if (owner) { |
4204 | /* | |
4205 | * Since delayed_put_task_struct() also drops the last | |
4206 | * task reference we can safely take a new reference | |
4207 | * while holding the rcu_read_lock(). | |
4208 | */ | |
4209 | get_task_struct(owner); | |
4210 | } | |
4211 | rcu_read_unlock(); | |
4212 | ||
4213 | if (owner) { | |
f63a8daa PZ |
4214 | /* |
4215 | * If we're here through perf_event_exit_task() we're already | |
4216 | * holding ctx->mutex which would be an inversion wrt. the | |
4217 | * normal lock order. | |
4218 | * | |
4219 | * However we can safely take this lock because its the child | |
4220 | * ctx->mutex. | |
4221 | */ | |
4222 | mutex_lock_nested(&owner->perf_event_mutex, SINGLE_DEPTH_NESTING); | |
4223 | ||
8882135b PZ |
4224 | /* |
4225 | * We have to re-check the event->owner field, if it is cleared | |
4226 | * we raced with perf_event_exit_task(), acquiring the mutex | |
4227 | * ensured they're done, and we can proceed with freeing the | |
4228 | * event. | |
4229 | */ | |
f47c02c0 | 4230 | if (event->owner) { |
8882135b | 4231 | list_del_init(&event->owner_entry); |
f47c02c0 PZ |
4232 | smp_store_release(&event->owner, NULL); |
4233 | } | |
8882135b PZ |
4234 | mutex_unlock(&owner->perf_event_mutex); |
4235 | put_task_struct(owner); | |
4236 | } | |
f8697762 JO |
4237 | } |
4238 | ||
f8697762 JO |
4239 | static void put_event(struct perf_event *event) |
4240 | { | |
f8697762 JO |
4241 | if (!atomic_long_dec_and_test(&event->refcount)) |
4242 | return; | |
4243 | ||
c6e5b732 PZ |
4244 | _free_event(event); |
4245 | } | |
4246 | ||
4247 | /* | |
4248 | * Kill an event dead; while event:refcount will preserve the event | |
4249 | * object, it will not preserve its functionality. Once the last 'user' | |
4250 | * gives up the object, we'll destroy the thing. | |
4251 | */ | |
4252 | int perf_event_release_kernel(struct perf_event *event) | |
4253 | { | |
a4f4bb6d | 4254 | struct perf_event_context *ctx = event->ctx; |
c6e5b732 | 4255 | struct perf_event *child, *tmp; |
82d94856 | 4256 | LIST_HEAD(free_list); |
c6e5b732 | 4257 | |
a4f4bb6d PZ |
4258 | /* |
4259 | * If we got here through err_file: fput(event_file); we will not have | |
4260 | * attached to a context yet. | |
4261 | */ | |
4262 | if (!ctx) { | |
4263 | WARN_ON_ONCE(event->attach_state & | |
4264 | (PERF_ATTACH_CONTEXT|PERF_ATTACH_GROUP)); | |
4265 | goto no_ctx; | |
4266 | } | |
4267 | ||
f8697762 JO |
4268 | if (!is_kernel_event(event)) |
4269 | perf_remove_from_owner(event); | |
8882135b | 4270 | |
5fa7c8ec | 4271 | ctx = perf_event_ctx_lock(event); |
a83fe28e | 4272 | WARN_ON_ONCE(ctx->parent_ctx); |
a69b0ca4 | 4273 | perf_remove_from_context(event, DETACH_GROUP); |
683ede43 | 4274 | |
a69b0ca4 | 4275 | raw_spin_lock_irq(&ctx->lock); |
683ede43 | 4276 | /* |
d8a8cfc7 | 4277 | * Mark this event as STATE_DEAD, there is no external reference to it |
a69b0ca4 | 4278 | * anymore. |
683ede43 | 4279 | * |
a69b0ca4 PZ |
4280 | * Anybody acquiring event->child_mutex after the below loop _must_ |
4281 | * also see this, most importantly inherit_event() which will avoid | |
4282 | * placing more children on the list. | |
683ede43 | 4283 | * |
c6e5b732 PZ |
4284 | * Thus this guarantees that we will in fact observe and kill _ALL_ |
4285 | * child events. | |
683ede43 | 4286 | */ |
a69b0ca4 PZ |
4287 | event->state = PERF_EVENT_STATE_DEAD; |
4288 | raw_spin_unlock_irq(&ctx->lock); | |
4289 | ||
4290 | perf_event_ctx_unlock(event, ctx); | |
683ede43 | 4291 | |
c6e5b732 PZ |
4292 | again: |
4293 | mutex_lock(&event->child_mutex); | |
4294 | list_for_each_entry(child, &event->child_list, child_list) { | |
a6fa941d | 4295 | |
c6e5b732 PZ |
4296 | /* |
4297 | * Cannot change, child events are not migrated, see the | |
4298 | * comment with perf_event_ctx_lock_nested(). | |
4299 | */ | |
506458ef | 4300 | ctx = READ_ONCE(child->ctx); |
c6e5b732 PZ |
4301 | /* |
4302 | * Since child_mutex nests inside ctx::mutex, we must jump | |
4303 | * through hoops. We start by grabbing a reference on the ctx. | |
4304 | * | |
4305 | * Since the event cannot get freed while we hold the | |
4306 | * child_mutex, the context must also exist and have a !0 | |
4307 | * reference count. | |
4308 | */ | |
4309 | get_ctx(ctx); | |
4310 | ||
4311 | /* | |
4312 | * Now that we have a ctx ref, we can drop child_mutex, and | |
4313 | * acquire ctx::mutex without fear of it going away. Then we | |
4314 | * can re-acquire child_mutex. | |
4315 | */ | |
4316 | mutex_unlock(&event->child_mutex); | |
4317 | mutex_lock(&ctx->mutex); | |
4318 | mutex_lock(&event->child_mutex); | |
4319 | ||
4320 | /* | |
4321 | * Now that we hold ctx::mutex and child_mutex, revalidate our | |
4322 | * state, if child is still the first entry, it didn't get freed | |
4323 | * and we can continue doing so. | |
4324 | */ | |
4325 | tmp = list_first_entry_or_null(&event->child_list, | |
4326 | struct perf_event, child_list); | |
4327 | if (tmp == child) { | |
4328 | perf_remove_from_context(child, DETACH_GROUP); | |
82d94856 | 4329 | list_move(&child->child_list, &free_list); |
c6e5b732 PZ |
4330 | /* |
4331 | * This matches the refcount bump in inherit_event(); | |
4332 | * this can't be the last reference. | |
4333 | */ | |
4334 | put_event(event); | |
4335 | } | |
4336 | ||
4337 | mutex_unlock(&event->child_mutex); | |
4338 | mutex_unlock(&ctx->mutex); | |
4339 | put_ctx(ctx); | |
4340 | goto again; | |
4341 | } | |
4342 | mutex_unlock(&event->child_mutex); | |
4343 | ||
82d94856 PZ |
4344 | list_for_each_entry_safe(child, tmp, &free_list, child_list) { |
4345 | list_del(&child->child_list); | |
4346 | free_event(child); | |
4347 | } | |
4348 | ||
a4f4bb6d PZ |
4349 | no_ctx: |
4350 | put_event(event); /* Must be the 'last' reference */ | |
683ede43 PZ |
4351 | return 0; |
4352 | } | |
4353 | EXPORT_SYMBOL_GPL(perf_event_release_kernel); | |
4354 | ||
8b10c5e2 PZ |
4355 | /* |
4356 | * Called when the last reference to the file is gone. | |
4357 | */ | |
a6fa941d AV |
4358 | static int perf_release(struct inode *inode, struct file *file) |
4359 | { | |
c6e5b732 | 4360 | perf_event_release_kernel(file->private_data); |
a6fa941d | 4361 | return 0; |
fb0459d7 | 4362 | } |
fb0459d7 | 4363 | |
ca0dd44c | 4364 | static u64 __perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) |
e53c0994 | 4365 | { |
cdd6c482 | 4366 | struct perf_event *child; |
e53c0994 PZ |
4367 | u64 total = 0; |
4368 | ||
59ed446f PZ |
4369 | *enabled = 0; |
4370 | *running = 0; | |
4371 | ||
6f10581a | 4372 | mutex_lock(&event->child_mutex); |
01add3ea | 4373 | |
7d88962e | 4374 | (void)perf_event_read(event, false); |
01add3ea SB |
4375 | total += perf_event_count(event); |
4376 | ||
59ed446f PZ |
4377 | *enabled += event->total_time_enabled + |
4378 | atomic64_read(&event->child_total_time_enabled); | |
4379 | *running += event->total_time_running + | |
4380 | atomic64_read(&event->child_total_time_running); | |
4381 | ||
4382 | list_for_each_entry(child, &event->child_list, child_list) { | |
7d88962e | 4383 | (void)perf_event_read(child, false); |
01add3ea | 4384 | total += perf_event_count(child); |
59ed446f PZ |
4385 | *enabled += child->total_time_enabled; |
4386 | *running += child->total_time_running; | |
4387 | } | |
6f10581a | 4388 | mutex_unlock(&event->child_mutex); |
e53c0994 PZ |
4389 | |
4390 | return total; | |
4391 | } | |
ca0dd44c PZ |
4392 | |
4393 | u64 perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) | |
4394 | { | |
4395 | struct perf_event_context *ctx; | |
4396 | u64 count; | |
4397 | ||
4398 | ctx = perf_event_ctx_lock(event); | |
4399 | count = __perf_event_read_value(event, enabled, running); | |
4400 | perf_event_ctx_unlock(event, ctx); | |
4401 | ||
4402 | return count; | |
4403 | } | |
fb0459d7 | 4404 | EXPORT_SYMBOL_GPL(perf_event_read_value); |
e53c0994 | 4405 | |
7d88962e | 4406 | static int __perf_read_group_add(struct perf_event *leader, |
fa8c2693 | 4407 | u64 read_format, u64 *values) |
3dab77fb | 4408 | { |
2aeb1883 | 4409 | struct perf_event_context *ctx = leader->ctx; |
fa8c2693 | 4410 | struct perf_event *sub; |
2aeb1883 | 4411 | unsigned long flags; |
fa8c2693 | 4412 | int n = 1; /* skip @nr */ |
7d88962e | 4413 | int ret; |
f63a8daa | 4414 | |
7d88962e SB |
4415 | ret = perf_event_read(leader, true); |
4416 | if (ret) | |
4417 | return ret; | |
abf4868b | 4418 | |
a9cd8194 PZ |
4419 | raw_spin_lock_irqsave(&ctx->lock, flags); |
4420 | ||
fa8c2693 PZ |
4421 | /* |
4422 | * Since we co-schedule groups, {enabled,running} times of siblings | |
4423 | * will be identical to those of the leader, so we only publish one | |
4424 | * set. | |
4425 | */ | |
4426 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { | |
4427 | values[n++] += leader->total_time_enabled + | |
4428 | atomic64_read(&leader->child_total_time_enabled); | |
4429 | } | |
3dab77fb | 4430 | |
fa8c2693 PZ |
4431 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { |
4432 | values[n++] += leader->total_time_running + | |
4433 | atomic64_read(&leader->child_total_time_running); | |
4434 | } | |
4435 | ||
4436 | /* | |
4437 | * Write {count,id} tuples for every sibling. | |
4438 | */ | |
4439 | values[n++] += perf_event_count(leader); | |
abf4868b PZ |
4440 | if (read_format & PERF_FORMAT_ID) |
4441 | values[n++] = primary_event_id(leader); | |
3dab77fb | 4442 | |
fa8c2693 PZ |
4443 | list_for_each_entry(sub, &leader->sibling_list, group_entry) { |
4444 | values[n++] += perf_event_count(sub); | |
4445 | if (read_format & PERF_FORMAT_ID) | |
4446 | values[n++] = primary_event_id(sub); | |
4447 | } | |
7d88962e | 4448 | |
2aeb1883 | 4449 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
7d88962e | 4450 | return 0; |
fa8c2693 | 4451 | } |
3dab77fb | 4452 | |
fa8c2693 PZ |
4453 | static int perf_read_group(struct perf_event *event, |
4454 | u64 read_format, char __user *buf) | |
4455 | { | |
4456 | struct perf_event *leader = event->group_leader, *child; | |
4457 | struct perf_event_context *ctx = leader->ctx; | |
7d88962e | 4458 | int ret; |
fa8c2693 | 4459 | u64 *values; |
3dab77fb | 4460 | |
fa8c2693 | 4461 | lockdep_assert_held(&ctx->mutex); |
3dab77fb | 4462 | |
fa8c2693 PZ |
4463 | values = kzalloc(event->read_size, GFP_KERNEL); |
4464 | if (!values) | |
4465 | return -ENOMEM; | |
3dab77fb | 4466 | |
fa8c2693 PZ |
4467 | values[0] = 1 + leader->nr_siblings; |
4468 | ||
4469 | /* | |
4470 | * By locking the child_mutex of the leader we effectively | |
4471 | * lock the child list of all siblings.. XXX explain how. | |
4472 | */ | |
4473 | mutex_lock(&leader->child_mutex); | |
abf4868b | 4474 | |
7d88962e SB |
4475 | ret = __perf_read_group_add(leader, read_format, values); |
4476 | if (ret) | |
4477 | goto unlock; | |
4478 | ||
4479 | list_for_each_entry(child, &leader->child_list, child_list) { | |
4480 | ret = __perf_read_group_add(child, read_format, values); | |
4481 | if (ret) | |
4482 | goto unlock; | |
4483 | } | |
abf4868b | 4484 | |
fa8c2693 | 4485 | mutex_unlock(&leader->child_mutex); |
abf4868b | 4486 | |
7d88962e | 4487 | ret = event->read_size; |
fa8c2693 PZ |
4488 | if (copy_to_user(buf, values, event->read_size)) |
4489 | ret = -EFAULT; | |
7d88962e | 4490 | goto out; |
fa8c2693 | 4491 | |
7d88962e SB |
4492 | unlock: |
4493 | mutex_unlock(&leader->child_mutex); | |
4494 | out: | |
fa8c2693 | 4495 | kfree(values); |
abf4868b | 4496 | return ret; |
3dab77fb PZ |
4497 | } |
4498 | ||
b15f495b | 4499 | static int perf_read_one(struct perf_event *event, |
3dab77fb PZ |
4500 | u64 read_format, char __user *buf) |
4501 | { | |
59ed446f | 4502 | u64 enabled, running; |
3dab77fb PZ |
4503 | u64 values[4]; |
4504 | int n = 0; | |
4505 | ||
ca0dd44c | 4506 | values[n++] = __perf_event_read_value(event, &enabled, &running); |
59ed446f PZ |
4507 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) |
4508 | values[n++] = enabled; | |
4509 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
4510 | values[n++] = running; | |
3dab77fb | 4511 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 4512 | values[n++] = primary_event_id(event); |
3dab77fb PZ |
4513 | |
4514 | if (copy_to_user(buf, values, n * sizeof(u64))) | |
4515 | return -EFAULT; | |
4516 | ||
4517 | return n * sizeof(u64); | |
4518 | } | |
4519 | ||
dc633982 JO |
4520 | static bool is_event_hup(struct perf_event *event) |
4521 | { | |
4522 | bool no_children; | |
4523 | ||
a69b0ca4 | 4524 | if (event->state > PERF_EVENT_STATE_EXIT) |
dc633982 JO |
4525 | return false; |
4526 | ||
4527 | mutex_lock(&event->child_mutex); | |
4528 | no_children = list_empty(&event->child_list); | |
4529 | mutex_unlock(&event->child_mutex); | |
4530 | return no_children; | |
4531 | } | |
4532 | ||
0793a61d | 4533 | /* |
cdd6c482 | 4534 | * Read the performance event - simple non blocking version for now |
0793a61d TG |
4535 | */ |
4536 | static ssize_t | |
b15f495b | 4537 | __perf_read(struct perf_event *event, char __user *buf, size_t count) |
0793a61d | 4538 | { |
cdd6c482 | 4539 | u64 read_format = event->attr.read_format; |
3dab77fb | 4540 | int ret; |
0793a61d | 4541 | |
3b6f9e5c | 4542 | /* |
cdd6c482 | 4543 | * Return end-of-file for a read on a event that is in |
3b6f9e5c PM |
4544 | * error state (i.e. because it was pinned but it couldn't be |
4545 | * scheduled on to the CPU at some point). | |
4546 | */ | |
cdd6c482 | 4547 | if (event->state == PERF_EVENT_STATE_ERROR) |
3b6f9e5c PM |
4548 | return 0; |
4549 | ||
c320c7b7 | 4550 | if (count < event->read_size) |
3dab77fb PZ |
4551 | return -ENOSPC; |
4552 | ||
cdd6c482 | 4553 | WARN_ON_ONCE(event->ctx->parent_ctx); |
3dab77fb | 4554 | if (read_format & PERF_FORMAT_GROUP) |
b15f495b | 4555 | ret = perf_read_group(event, read_format, buf); |
3dab77fb | 4556 | else |
b15f495b | 4557 | ret = perf_read_one(event, read_format, buf); |
0793a61d | 4558 | |
3dab77fb | 4559 | return ret; |
0793a61d TG |
4560 | } |
4561 | ||
0793a61d TG |
4562 | static ssize_t |
4563 | perf_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) | |
4564 | { | |
cdd6c482 | 4565 | struct perf_event *event = file->private_data; |
f63a8daa PZ |
4566 | struct perf_event_context *ctx; |
4567 | int ret; | |
0793a61d | 4568 | |
f63a8daa | 4569 | ctx = perf_event_ctx_lock(event); |
b15f495b | 4570 | ret = __perf_read(event, buf, count); |
f63a8daa PZ |
4571 | perf_event_ctx_unlock(event, ctx); |
4572 | ||
4573 | return ret; | |
0793a61d TG |
4574 | } |
4575 | ||
4576 | static unsigned int perf_poll(struct file *file, poll_table *wait) | |
4577 | { | |
cdd6c482 | 4578 | struct perf_event *event = file->private_data; |
76369139 | 4579 | struct ring_buffer *rb; |
61b67684 | 4580 | unsigned int events = POLLHUP; |
c7138f37 | 4581 | |
e708d7ad | 4582 | poll_wait(file, &event->waitq, wait); |
179033b3 | 4583 | |
dc633982 | 4584 | if (is_event_hup(event)) |
179033b3 | 4585 | return events; |
c7138f37 | 4586 | |
10c6db11 | 4587 | /* |
9bb5d40c PZ |
4588 | * Pin the event->rb by taking event->mmap_mutex; otherwise |
4589 | * perf_event_set_output() can swizzle our rb and make us miss wakeups. | |
10c6db11 PZ |
4590 | */ |
4591 | mutex_lock(&event->mmap_mutex); | |
9bb5d40c PZ |
4592 | rb = event->rb; |
4593 | if (rb) | |
76369139 | 4594 | events = atomic_xchg(&rb->poll, 0); |
10c6db11 | 4595 | mutex_unlock(&event->mmap_mutex); |
0793a61d TG |
4596 | return events; |
4597 | } | |
4598 | ||
f63a8daa | 4599 | static void _perf_event_reset(struct perf_event *event) |
6de6a7b9 | 4600 | { |
7d88962e | 4601 | (void)perf_event_read(event, false); |
e7850595 | 4602 | local64_set(&event->count, 0); |
cdd6c482 | 4603 | perf_event_update_userpage(event); |
3df5edad PZ |
4604 | } |
4605 | ||
c93f7669 | 4606 | /* |
cdd6c482 IM |
4607 | * Holding the top-level event's child_mutex means that any |
4608 | * descendant process that has inherited this event will block | |
8ba289b8 | 4609 | * in perf_event_exit_event() if it goes to exit, thus satisfying the |
cdd6c482 | 4610 | * task existence requirements of perf_event_enable/disable. |
c93f7669 | 4611 | */ |
cdd6c482 IM |
4612 | static void perf_event_for_each_child(struct perf_event *event, |
4613 | void (*func)(struct perf_event *)) | |
3df5edad | 4614 | { |
cdd6c482 | 4615 | struct perf_event *child; |
3df5edad | 4616 | |
cdd6c482 | 4617 | WARN_ON_ONCE(event->ctx->parent_ctx); |
f63a8daa | 4618 | |
cdd6c482 IM |
4619 | mutex_lock(&event->child_mutex); |
4620 | func(event); | |
4621 | list_for_each_entry(child, &event->child_list, child_list) | |
3df5edad | 4622 | func(child); |
cdd6c482 | 4623 | mutex_unlock(&event->child_mutex); |
3df5edad PZ |
4624 | } |
4625 | ||
cdd6c482 IM |
4626 | static void perf_event_for_each(struct perf_event *event, |
4627 | void (*func)(struct perf_event *)) | |
3df5edad | 4628 | { |
cdd6c482 IM |
4629 | struct perf_event_context *ctx = event->ctx; |
4630 | struct perf_event *sibling; | |
3df5edad | 4631 | |
f63a8daa PZ |
4632 | lockdep_assert_held(&ctx->mutex); |
4633 | ||
cdd6c482 | 4634 | event = event->group_leader; |
75f937f2 | 4635 | |
cdd6c482 | 4636 | perf_event_for_each_child(event, func); |
cdd6c482 | 4637 | list_for_each_entry(sibling, &event->sibling_list, group_entry) |
724b6daa | 4638 | perf_event_for_each_child(sibling, func); |
6de6a7b9 PZ |
4639 | } |
4640 | ||
fae3fde6 PZ |
4641 | static void __perf_event_period(struct perf_event *event, |
4642 | struct perf_cpu_context *cpuctx, | |
4643 | struct perf_event_context *ctx, | |
4644 | void *info) | |
c7999c6f | 4645 | { |
fae3fde6 | 4646 | u64 value = *((u64 *)info); |
c7999c6f | 4647 | bool active; |
08247e31 | 4648 | |
cdd6c482 | 4649 | if (event->attr.freq) { |
cdd6c482 | 4650 | event->attr.sample_freq = value; |
08247e31 | 4651 | } else { |
cdd6c482 IM |
4652 | event->attr.sample_period = value; |
4653 | event->hw.sample_period = value; | |
08247e31 | 4654 | } |
bad7192b PZ |
4655 | |
4656 | active = (event->state == PERF_EVENT_STATE_ACTIVE); | |
4657 | if (active) { | |
4658 | perf_pmu_disable(ctx->pmu); | |
1e02cd40 PZ |
4659 | /* |
4660 | * We could be throttled; unthrottle now to avoid the tick | |
4661 | * trying to unthrottle while we already re-started the event. | |
4662 | */ | |
4663 | if (event->hw.interrupts == MAX_INTERRUPTS) { | |
4664 | event->hw.interrupts = 0; | |
4665 | perf_log_throttle(event, 1); | |
4666 | } | |
bad7192b PZ |
4667 | event->pmu->stop(event, PERF_EF_UPDATE); |
4668 | } | |
4669 | ||
4670 | local64_set(&event->hw.period_left, 0); | |
4671 | ||
4672 | if (active) { | |
4673 | event->pmu->start(event, PERF_EF_RELOAD); | |
4674 | perf_pmu_enable(ctx->pmu); | |
4675 | } | |
c7999c6f PZ |
4676 | } |
4677 | ||
57f9f919 JO |
4678 | static int perf_event_check_period(struct perf_event *event, u64 value) |
4679 | { | |
4680 | return event->pmu->check_period(event, value); | |
4681 | } | |
4682 | ||
c7999c6f PZ |
4683 | static int perf_event_period(struct perf_event *event, u64 __user *arg) |
4684 | { | |
c7999c6f PZ |
4685 | u64 value; |
4686 | ||
4687 | if (!is_sampling_event(event)) | |
4688 | return -EINVAL; | |
4689 | ||
4690 | if (copy_from_user(&value, arg, sizeof(value))) | |
4691 | return -EFAULT; | |
4692 | ||
4693 | if (!value) | |
4694 | return -EINVAL; | |
4695 | ||
4696 | if (event->attr.freq && value > sysctl_perf_event_sample_rate) | |
4697 | return -EINVAL; | |
4698 | ||
57f9f919 JO |
4699 | if (perf_event_check_period(event, value)) |
4700 | return -EINVAL; | |
4701 | ||
9d7fdcb7 RB |
4702 | if (!event->attr.freq && (value & (1ULL << 63))) |
4703 | return -EINVAL; | |
4704 | ||
fae3fde6 | 4705 | event_function_call(event, __perf_event_period, &value); |
08247e31 | 4706 | |
c7999c6f | 4707 | return 0; |
08247e31 PZ |
4708 | } |
4709 | ||
ac9721f3 PZ |
4710 | static const struct file_operations perf_fops; |
4711 | ||
2903ff01 | 4712 | static inline int perf_fget_light(int fd, struct fd *p) |
ac9721f3 | 4713 | { |
2903ff01 AV |
4714 | struct fd f = fdget(fd); |
4715 | if (!f.file) | |
4716 | return -EBADF; | |
ac9721f3 | 4717 | |
2903ff01 AV |
4718 | if (f.file->f_op != &perf_fops) { |
4719 | fdput(f); | |
4720 | return -EBADF; | |
ac9721f3 | 4721 | } |
2903ff01 AV |
4722 | *p = f; |
4723 | return 0; | |
ac9721f3 PZ |
4724 | } |
4725 | ||
4726 | static int perf_event_set_output(struct perf_event *event, | |
4727 | struct perf_event *output_event); | |
6fb2915d | 4728 | static int perf_event_set_filter(struct perf_event *event, void __user *arg); |
2541517c | 4729 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd); |
a4be7c27 | 4730 | |
f63a8daa | 4731 | static long _perf_ioctl(struct perf_event *event, unsigned int cmd, unsigned long arg) |
d859e29f | 4732 | { |
cdd6c482 | 4733 | void (*func)(struct perf_event *); |
3df5edad | 4734 | u32 flags = arg; |
d859e29f PM |
4735 | |
4736 | switch (cmd) { | |
cdd6c482 | 4737 | case PERF_EVENT_IOC_ENABLE: |
f63a8daa | 4738 | func = _perf_event_enable; |
d859e29f | 4739 | break; |
cdd6c482 | 4740 | case PERF_EVENT_IOC_DISABLE: |
f63a8daa | 4741 | func = _perf_event_disable; |
79f14641 | 4742 | break; |
cdd6c482 | 4743 | case PERF_EVENT_IOC_RESET: |
f63a8daa | 4744 | func = _perf_event_reset; |
6de6a7b9 | 4745 | break; |
3df5edad | 4746 | |
cdd6c482 | 4747 | case PERF_EVENT_IOC_REFRESH: |
f63a8daa | 4748 | return _perf_event_refresh(event, arg); |
08247e31 | 4749 | |
cdd6c482 IM |
4750 | case PERF_EVENT_IOC_PERIOD: |
4751 | return perf_event_period(event, (u64 __user *)arg); | |
08247e31 | 4752 | |
cf4957f1 JO |
4753 | case PERF_EVENT_IOC_ID: |
4754 | { | |
4755 | u64 id = primary_event_id(event); | |
4756 | ||
4757 | if (copy_to_user((void __user *)arg, &id, sizeof(id))) | |
4758 | return -EFAULT; | |
4759 | return 0; | |
4760 | } | |
4761 | ||
cdd6c482 | 4762 | case PERF_EVENT_IOC_SET_OUTPUT: |
ac9721f3 | 4763 | { |
ac9721f3 | 4764 | int ret; |
ac9721f3 | 4765 | if (arg != -1) { |
2903ff01 AV |
4766 | struct perf_event *output_event; |
4767 | struct fd output; | |
4768 | ret = perf_fget_light(arg, &output); | |
4769 | if (ret) | |
4770 | return ret; | |
4771 | output_event = output.file->private_data; | |
4772 | ret = perf_event_set_output(event, output_event); | |
4773 | fdput(output); | |
4774 | } else { | |
4775 | ret = perf_event_set_output(event, NULL); | |
ac9721f3 | 4776 | } |
ac9721f3 PZ |
4777 | return ret; |
4778 | } | |
a4be7c27 | 4779 | |
6fb2915d LZ |
4780 | case PERF_EVENT_IOC_SET_FILTER: |
4781 | return perf_event_set_filter(event, (void __user *)arg); | |
4782 | ||
2541517c AS |
4783 | case PERF_EVENT_IOC_SET_BPF: |
4784 | return perf_event_set_bpf_prog(event, arg); | |
4785 | ||
86e7972f WN |
4786 | case PERF_EVENT_IOC_PAUSE_OUTPUT: { |
4787 | struct ring_buffer *rb; | |
4788 | ||
4789 | rcu_read_lock(); | |
4790 | rb = rcu_dereference(event->rb); | |
4791 | if (!rb || !rb->nr_pages) { | |
4792 | rcu_read_unlock(); | |
4793 | return -EINVAL; | |
4794 | } | |
4795 | rb_toggle_paused(rb, !!arg); | |
4796 | rcu_read_unlock(); | |
4797 | return 0; | |
4798 | } | |
d859e29f | 4799 | default: |
3df5edad | 4800 | return -ENOTTY; |
d859e29f | 4801 | } |
3df5edad PZ |
4802 | |
4803 | if (flags & PERF_IOC_FLAG_GROUP) | |
cdd6c482 | 4804 | perf_event_for_each(event, func); |
3df5edad | 4805 | else |
cdd6c482 | 4806 | perf_event_for_each_child(event, func); |
3df5edad PZ |
4807 | |
4808 | return 0; | |
d859e29f PM |
4809 | } |
4810 | ||
f63a8daa PZ |
4811 | static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
4812 | { | |
4813 | struct perf_event *event = file->private_data; | |
4814 | struct perf_event_context *ctx; | |
4815 | long ret; | |
4816 | ||
4817 | ctx = perf_event_ctx_lock(event); | |
4818 | ret = _perf_ioctl(event, cmd, arg); | |
4819 | perf_event_ctx_unlock(event, ctx); | |
4820 | ||
4821 | return ret; | |
4822 | } | |
4823 | ||
b3f20785 PM |
4824 | #ifdef CONFIG_COMPAT |
4825 | static long perf_compat_ioctl(struct file *file, unsigned int cmd, | |
4826 | unsigned long arg) | |
4827 | { | |
4828 | switch (_IOC_NR(cmd)) { | |
4829 | case _IOC_NR(PERF_EVENT_IOC_SET_FILTER): | |
4830 | case _IOC_NR(PERF_EVENT_IOC_ID): | |
4831 | /* Fix up pointer size (usually 4 -> 8 in 32-on-64-bit case */ | |
4832 | if (_IOC_SIZE(cmd) == sizeof(compat_uptr_t)) { | |
4833 | cmd &= ~IOCSIZE_MASK; | |
4834 | cmd |= sizeof(void *) << IOCSIZE_SHIFT; | |
4835 | } | |
4836 | break; | |
4837 | } | |
4838 | return perf_ioctl(file, cmd, arg); | |
4839 | } | |
4840 | #else | |
4841 | # define perf_compat_ioctl NULL | |
4842 | #endif | |
4843 | ||
cdd6c482 | 4844 | int perf_event_task_enable(void) |
771d7cde | 4845 | { |
f63a8daa | 4846 | struct perf_event_context *ctx; |
cdd6c482 | 4847 | struct perf_event *event; |
771d7cde | 4848 | |
cdd6c482 | 4849 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
4850 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
4851 | ctx = perf_event_ctx_lock(event); | |
4852 | perf_event_for_each_child(event, _perf_event_enable); | |
4853 | perf_event_ctx_unlock(event, ctx); | |
4854 | } | |
cdd6c482 | 4855 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
4856 | |
4857 | return 0; | |
4858 | } | |
4859 | ||
cdd6c482 | 4860 | int perf_event_task_disable(void) |
771d7cde | 4861 | { |
f63a8daa | 4862 | struct perf_event_context *ctx; |
cdd6c482 | 4863 | struct perf_event *event; |
771d7cde | 4864 | |
cdd6c482 | 4865 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
4866 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
4867 | ctx = perf_event_ctx_lock(event); | |
4868 | perf_event_for_each_child(event, _perf_event_disable); | |
4869 | perf_event_ctx_unlock(event, ctx); | |
4870 | } | |
cdd6c482 | 4871 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
4872 | |
4873 | return 0; | |
4874 | } | |
4875 | ||
cdd6c482 | 4876 | static int perf_event_index(struct perf_event *event) |
194002b2 | 4877 | { |
a4eaf7f1 PZ |
4878 | if (event->hw.state & PERF_HES_STOPPED) |
4879 | return 0; | |
4880 | ||
cdd6c482 | 4881 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
194002b2 PZ |
4882 | return 0; |
4883 | ||
35edc2a5 | 4884 | return event->pmu->event_idx(event); |
194002b2 PZ |
4885 | } |
4886 | ||
c4794295 | 4887 | static void calc_timer_values(struct perf_event *event, |
e3f3541c | 4888 | u64 *now, |
7f310a5d EM |
4889 | u64 *enabled, |
4890 | u64 *running) | |
c4794295 | 4891 | { |
e3f3541c | 4892 | u64 ctx_time; |
c4794295 | 4893 | |
e3f3541c PZ |
4894 | *now = perf_clock(); |
4895 | ctx_time = event->shadow_ctx_time + *now; | |
0d3d73aa | 4896 | __perf_update_times(event, ctx_time, enabled, running); |
c4794295 EM |
4897 | } |
4898 | ||
fa731587 PZ |
4899 | static void perf_event_init_userpage(struct perf_event *event) |
4900 | { | |
4901 | struct perf_event_mmap_page *userpg; | |
4902 | struct ring_buffer *rb; | |
4903 | ||
4904 | rcu_read_lock(); | |
4905 | rb = rcu_dereference(event->rb); | |
4906 | if (!rb) | |
4907 | goto unlock; | |
4908 | ||
4909 | userpg = rb->user_page; | |
4910 | ||
4911 | /* Allow new userspace to detect that bit 0 is deprecated */ | |
4912 | userpg->cap_bit0_is_deprecated = 1; | |
4913 | userpg->size = offsetof(struct perf_event_mmap_page, __reserved); | |
e8c6deac AS |
4914 | userpg->data_offset = PAGE_SIZE; |
4915 | userpg->data_size = perf_data_size(rb); | |
fa731587 PZ |
4916 | |
4917 | unlock: | |
4918 | rcu_read_unlock(); | |
4919 | } | |
4920 | ||
c1317ec2 AL |
4921 | void __weak arch_perf_update_userpage( |
4922 | struct perf_event *event, struct perf_event_mmap_page *userpg, u64 now) | |
e3f3541c PZ |
4923 | { |
4924 | } | |
4925 | ||
38ff667b PZ |
4926 | /* |
4927 | * Callers need to ensure there can be no nesting of this function, otherwise | |
4928 | * the seqlock logic goes bad. We can not serialize this because the arch | |
4929 | * code calls this from NMI context. | |
4930 | */ | |
cdd6c482 | 4931 | void perf_event_update_userpage(struct perf_event *event) |
37d81828 | 4932 | { |
cdd6c482 | 4933 | struct perf_event_mmap_page *userpg; |
76369139 | 4934 | struct ring_buffer *rb; |
e3f3541c | 4935 | u64 enabled, running, now; |
38ff667b PZ |
4936 | |
4937 | rcu_read_lock(); | |
5ec4c599 PZ |
4938 | rb = rcu_dereference(event->rb); |
4939 | if (!rb) | |
4940 | goto unlock; | |
4941 | ||
0d641208 EM |
4942 | /* |
4943 | * compute total_time_enabled, total_time_running | |
4944 | * based on snapshot values taken when the event | |
4945 | * was last scheduled in. | |
4946 | * | |
4947 | * we cannot simply called update_context_time() | |
4948 | * because of locking issue as we can be called in | |
4949 | * NMI context | |
4950 | */ | |
e3f3541c | 4951 | calc_timer_values(event, &now, &enabled, &running); |
38ff667b | 4952 | |
76369139 | 4953 | userpg = rb->user_page; |
7b732a75 PZ |
4954 | /* |
4955 | * Disable preemption so as to not let the corresponding user-space | |
4956 | * spin too long if we get preempted. | |
4957 | */ | |
4958 | preempt_disable(); | |
37d81828 | 4959 | ++userpg->lock; |
92f22a38 | 4960 | barrier(); |
cdd6c482 | 4961 | userpg->index = perf_event_index(event); |
b5e58793 | 4962 | userpg->offset = perf_event_count(event); |
365a4038 | 4963 | if (userpg->index) |
e7850595 | 4964 | userpg->offset -= local64_read(&event->hw.prev_count); |
7b732a75 | 4965 | |
0d641208 | 4966 | userpg->time_enabled = enabled + |
cdd6c482 | 4967 | atomic64_read(&event->child_total_time_enabled); |
7f8b4e4e | 4968 | |
0d641208 | 4969 | userpg->time_running = running + |
cdd6c482 | 4970 | atomic64_read(&event->child_total_time_running); |
7f8b4e4e | 4971 | |
c1317ec2 | 4972 | arch_perf_update_userpage(event, userpg, now); |
e3f3541c | 4973 | |
92f22a38 | 4974 | barrier(); |
37d81828 | 4975 | ++userpg->lock; |
7b732a75 | 4976 | preempt_enable(); |
38ff667b | 4977 | unlock: |
7b732a75 | 4978 | rcu_read_unlock(); |
37d81828 | 4979 | } |
cee4409b | 4980 | EXPORT_SYMBOL_GPL(perf_event_update_userpage); |
37d81828 | 4981 | |
11bac800 | 4982 | static int perf_mmap_fault(struct vm_fault *vmf) |
906010b2 | 4983 | { |
11bac800 | 4984 | struct perf_event *event = vmf->vma->vm_file->private_data; |
76369139 | 4985 | struct ring_buffer *rb; |
906010b2 PZ |
4986 | int ret = VM_FAULT_SIGBUS; |
4987 | ||
4988 | if (vmf->flags & FAULT_FLAG_MKWRITE) { | |
4989 | if (vmf->pgoff == 0) | |
4990 | ret = 0; | |
4991 | return ret; | |
4992 | } | |
4993 | ||
4994 | rcu_read_lock(); | |
76369139 FW |
4995 | rb = rcu_dereference(event->rb); |
4996 | if (!rb) | |
906010b2 PZ |
4997 | goto unlock; |
4998 | ||
4999 | if (vmf->pgoff && (vmf->flags & FAULT_FLAG_WRITE)) | |
5000 | goto unlock; | |
5001 | ||
76369139 | 5002 | vmf->page = perf_mmap_to_page(rb, vmf->pgoff); |
906010b2 PZ |
5003 | if (!vmf->page) |
5004 | goto unlock; | |
5005 | ||
5006 | get_page(vmf->page); | |
11bac800 | 5007 | vmf->page->mapping = vmf->vma->vm_file->f_mapping; |
906010b2 PZ |
5008 | vmf->page->index = vmf->pgoff; |
5009 | ||
5010 | ret = 0; | |
5011 | unlock: | |
5012 | rcu_read_unlock(); | |
5013 | ||
5014 | return ret; | |
5015 | } | |
5016 | ||
10c6db11 PZ |
5017 | static void ring_buffer_attach(struct perf_event *event, |
5018 | struct ring_buffer *rb) | |
5019 | { | |
b69cf536 | 5020 | struct ring_buffer *old_rb = NULL; |
10c6db11 PZ |
5021 | unsigned long flags; |
5022 | ||
b69cf536 PZ |
5023 | if (event->rb) { |
5024 | /* | |
5025 | * Should be impossible, we set this when removing | |
5026 | * event->rb_entry and wait/clear when adding event->rb_entry. | |
5027 | */ | |
5028 | WARN_ON_ONCE(event->rcu_pending); | |
10c6db11 | 5029 | |
b69cf536 | 5030 | old_rb = event->rb; |
b69cf536 PZ |
5031 | spin_lock_irqsave(&old_rb->event_lock, flags); |
5032 | list_del_rcu(&event->rb_entry); | |
5033 | spin_unlock_irqrestore(&old_rb->event_lock, flags); | |
10c6db11 | 5034 | |
2f993cf0 ON |
5035 | event->rcu_batches = get_state_synchronize_rcu(); |
5036 | event->rcu_pending = 1; | |
b69cf536 | 5037 | } |
10c6db11 | 5038 | |
b69cf536 | 5039 | if (rb) { |
2f993cf0 ON |
5040 | if (event->rcu_pending) { |
5041 | cond_synchronize_rcu(event->rcu_batches); | |
5042 | event->rcu_pending = 0; | |
5043 | } | |
5044 | ||
b69cf536 PZ |
5045 | spin_lock_irqsave(&rb->event_lock, flags); |
5046 | list_add_rcu(&event->rb_entry, &rb->event_list); | |
5047 | spin_unlock_irqrestore(&rb->event_lock, flags); | |
5048 | } | |
5049 | ||
767ae086 AS |
5050 | /* |
5051 | * Avoid racing with perf_mmap_close(AUX): stop the event | |
5052 | * before swizzling the event::rb pointer; if it's getting | |
5053 | * unmapped, its aux_mmap_count will be 0 and it won't | |
5054 | * restart. See the comment in __perf_pmu_output_stop(). | |
5055 | * | |
5056 | * Data will inevitably be lost when set_output is done in | |
5057 | * mid-air, but then again, whoever does it like this is | |
5058 | * not in for the data anyway. | |
5059 | */ | |
5060 | if (has_aux(event)) | |
5061 | perf_event_stop(event, 0); | |
5062 | ||
b69cf536 PZ |
5063 | rcu_assign_pointer(event->rb, rb); |
5064 | ||
5065 | if (old_rb) { | |
5066 | ring_buffer_put(old_rb); | |
5067 | /* | |
5068 | * Since we detached before setting the new rb, so that we | |
5069 | * could attach the new rb, we could have missed a wakeup. | |
5070 | * Provide it now. | |
5071 | */ | |
5072 | wake_up_all(&event->waitq); | |
5073 | } | |
10c6db11 PZ |
5074 | } |
5075 | ||
5076 | static void ring_buffer_wakeup(struct perf_event *event) | |
5077 | { | |
5078 | struct ring_buffer *rb; | |
5079 | ||
5080 | rcu_read_lock(); | |
5081 | rb = rcu_dereference(event->rb); | |
9bb5d40c PZ |
5082 | if (rb) { |
5083 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) | |
5084 | wake_up_all(&event->waitq); | |
5085 | } | |
10c6db11 PZ |
5086 | rcu_read_unlock(); |
5087 | } | |
5088 | ||
fdc26706 | 5089 | struct ring_buffer *ring_buffer_get(struct perf_event *event) |
7b732a75 | 5090 | { |
76369139 | 5091 | struct ring_buffer *rb; |
7b732a75 | 5092 | |
ac9721f3 | 5093 | rcu_read_lock(); |
76369139 FW |
5094 | rb = rcu_dereference(event->rb); |
5095 | if (rb) { | |
5096 | if (!atomic_inc_not_zero(&rb->refcount)) | |
5097 | rb = NULL; | |
ac9721f3 PZ |
5098 | } |
5099 | rcu_read_unlock(); | |
5100 | ||
76369139 | 5101 | return rb; |
ac9721f3 PZ |
5102 | } |
5103 | ||
fdc26706 | 5104 | void ring_buffer_put(struct ring_buffer *rb) |
ac9721f3 | 5105 | { |
76369139 | 5106 | if (!atomic_dec_and_test(&rb->refcount)) |
ac9721f3 | 5107 | return; |
7b732a75 | 5108 | |
9bb5d40c | 5109 | WARN_ON_ONCE(!list_empty(&rb->event_list)); |
10c6db11 | 5110 | |
76369139 | 5111 | call_rcu(&rb->rcu_head, rb_free_rcu); |
7b732a75 PZ |
5112 | } |
5113 | ||
5114 | static void perf_mmap_open(struct vm_area_struct *vma) | |
5115 | { | |
cdd6c482 | 5116 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 5117 | |
cdd6c482 | 5118 | atomic_inc(&event->mmap_count); |
9bb5d40c | 5119 | atomic_inc(&event->rb->mmap_count); |
1e0fb9ec | 5120 | |
45bfb2e5 PZ |
5121 | if (vma->vm_pgoff) |
5122 | atomic_inc(&event->rb->aux_mmap_count); | |
5123 | ||
1e0fb9ec | 5124 | if (event->pmu->event_mapped) |
bfe33492 | 5125 | event->pmu->event_mapped(event, vma->vm_mm); |
7b732a75 PZ |
5126 | } |
5127 | ||
95ff4ca2 AS |
5128 | static void perf_pmu_output_stop(struct perf_event *event); |
5129 | ||
9bb5d40c PZ |
5130 | /* |
5131 | * A buffer can be mmap()ed multiple times; either directly through the same | |
5132 | * event, or through other events by use of perf_event_set_output(). | |
5133 | * | |
5134 | * In order to undo the VM accounting done by perf_mmap() we need to destroy | |
5135 | * the buffer here, where we still have a VM context. This means we need | |
5136 | * to detach all events redirecting to us. | |
5137 | */ | |
7b732a75 PZ |
5138 | static void perf_mmap_close(struct vm_area_struct *vma) |
5139 | { | |
cdd6c482 | 5140 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 5141 | |
b69cf536 | 5142 | struct ring_buffer *rb = ring_buffer_get(event); |
9bb5d40c PZ |
5143 | struct user_struct *mmap_user = rb->mmap_user; |
5144 | int mmap_locked = rb->mmap_locked; | |
5145 | unsigned long size = perf_data_size(rb); | |
789f90fc | 5146 | |
1e0fb9ec | 5147 | if (event->pmu->event_unmapped) |
bfe33492 | 5148 | event->pmu->event_unmapped(event, vma->vm_mm); |
1e0fb9ec | 5149 | |
45bfb2e5 PZ |
5150 | /* |
5151 | * rb->aux_mmap_count will always drop before rb->mmap_count and | |
5152 | * event->mmap_count, so it is ok to use event->mmap_mutex to | |
5153 | * serialize with perf_mmap here. | |
5154 | */ | |
5155 | if (rb_has_aux(rb) && vma->vm_pgoff == rb->aux_pgoff && | |
5156 | atomic_dec_and_mutex_lock(&rb->aux_mmap_count, &event->mmap_mutex)) { | |
95ff4ca2 AS |
5157 | /* |
5158 | * Stop all AUX events that are writing to this buffer, | |
5159 | * so that we can free its AUX pages and corresponding PMU | |
5160 | * data. Note that after rb::aux_mmap_count dropped to zero, | |
5161 | * they won't start any more (see perf_aux_output_begin()). | |
5162 | */ | |
5163 | perf_pmu_output_stop(event); | |
5164 | ||
5165 | /* now it's safe to free the pages */ | |
45bfb2e5 PZ |
5166 | atomic_long_sub(rb->aux_nr_pages, &mmap_user->locked_vm); |
5167 | vma->vm_mm->pinned_vm -= rb->aux_mmap_locked; | |
5168 | ||
95ff4ca2 | 5169 | /* this has to be the last one */ |
45bfb2e5 | 5170 | rb_free_aux(rb); |
95ff4ca2 AS |
5171 | WARN_ON_ONCE(atomic_read(&rb->aux_refcount)); |
5172 | ||
45bfb2e5 PZ |
5173 | mutex_unlock(&event->mmap_mutex); |
5174 | } | |
5175 | ||
9bb5d40c PZ |
5176 | atomic_dec(&rb->mmap_count); |
5177 | ||
5178 | if (!atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex)) | |
b69cf536 | 5179 | goto out_put; |
9bb5d40c | 5180 | |
b69cf536 | 5181 | ring_buffer_attach(event, NULL); |
9bb5d40c PZ |
5182 | mutex_unlock(&event->mmap_mutex); |
5183 | ||
5184 | /* If there's still other mmap()s of this buffer, we're done. */ | |
b69cf536 PZ |
5185 | if (atomic_read(&rb->mmap_count)) |
5186 | goto out_put; | |
ac9721f3 | 5187 | |
9bb5d40c PZ |
5188 | /* |
5189 | * No other mmap()s, detach from all other events that might redirect | |
5190 | * into the now unreachable buffer. Somewhat complicated by the | |
5191 | * fact that rb::event_lock otherwise nests inside mmap_mutex. | |
5192 | */ | |
5193 | again: | |
5194 | rcu_read_lock(); | |
5195 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) { | |
5196 | if (!atomic_long_inc_not_zero(&event->refcount)) { | |
5197 | /* | |
5198 | * This event is en-route to free_event() which will | |
5199 | * detach it and remove it from the list. | |
5200 | */ | |
5201 | continue; | |
5202 | } | |
5203 | rcu_read_unlock(); | |
789f90fc | 5204 | |
9bb5d40c PZ |
5205 | mutex_lock(&event->mmap_mutex); |
5206 | /* | |
5207 | * Check we didn't race with perf_event_set_output() which can | |
5208 | * swizzle the rb from under us while we were waiting to | |
5209 | * acquire mmap_mutex. | |
5210 | * | |
5211 | * If we find a different rb; ignore this event, a next | |
5212 | * iteration will no longer find it on the list. We have to | |
5213 | * still restart the iteration to make sure we're not now | |
5214 | * iterating the wrong list. | |
5215 | */ | |
b69cf536 PZ |
5216 | if (event->rb == rb) |
5217 | ring_buffer_attach(event, NULL); | |
5218 | ||
cdd6c482 | 5219 | mutex_unlock(&event->mmap_mutex); |
9bb5d40c | 5220 | put_event(event); |
ac9721f3 | 5221 | |
9bb5d40c PZ |
5222 | /* |
5223 | * Restart the iteration; either we're on the wrong list or | |
5224 | * destroyed its integrity by doing a deletion. | |
5225 | */ | |
5226 | goto again; | |
7b732a75 | 5227 | } |
9bb5d40c PZ |
5228 | rcu_read_unlock(); |
5229 | ||
5230 | /* | |
5231 | * It could be there's still a few 0-ref events on the list; they'll | |
5232 | * get cleaned up by free_event() -- they'll also still have their | |
5233 | * ref on the rb and will free it whenever they are done with it. | |
5234 | * | |
5235 | * Aside from that, this buffer is 'fully' detached and unmapped, | |
5236 | * undo the VM accounting. | |
5237 | */ | |
5238 | ||
5239 | atomic_long_sub((size >> PAGE_SHIFT) + 1, &mmap_user->locked_vm); | |
5240 | vma->vm_mm->pinned_vm -= mmap_locked; | |
5241 | free_uid(mmap_user); | |
5242 | ||
b69cf536 | 5243 | out_put: |
9bb5d40c | 5244 | ring_buffer_put(rb); /* could be last */ |
37d81828 PM |
5245 | } |
5246 | ||
f0f37e2f | 5247 | static const struct vm_operations_struct perf_mmap_vmops = { |
43a21ea8 | 5248 | .open = perf_mmap_open, |
45bfb2e5 | 5249 | .close = perf_mmap_close, /* non mergable */ |
43a21ea8 PZ |
5250 | .fault = perf_mmap_fault, |
5251 | .page_mkwrite = perf_mmap_fault, | |
37d81828 PM |
5252 | }; |
5253 | ||
5254 | static int perf_mmap(struct file *file, struct vm_area_struct *vma) | |
5255 | { | |
cdd6c482 | 5256 | struct perf_event *event = file->private_data; |
22a4f650 | 5257 | unsigned long user_locked, user_lock_limit; |
789f90fc | 5258 | struct user_struct *user = current_user(); |
22a4f650 | 5259 | unsigned long locked, lock_limit; |
45bfb2e5 | 5260 | struct ring_buffer *rb = NULL; |
7b732a75 PZ |
5261 | unsigned long vma_size; |
5262 | unsigned long nr_pages; | |
45bfb2e5 | 5263 | long user_extra = 0, extra = 0; |
d57e34fd | 5264 | int ret = 0, flags = 0; |
37d81828 | 5265 | |
c7920614 PZ |
5266 | /* |
5267 | * Don't allow mmap() of inherited per-task counters. This would | |
5268 | * create a performance issue due to all children writing to the | |
76369139 | 5269 | * same rb. |
c7920614 PZ |
5270 | */ |
5271 | if (event->cpu == -1 && event->attr.inherit) | |
5272 | return -EINVAL; | |
5273 | ||
43a21ea8 | 5274 | if (!(vma->vm_flags & VM_SHARED)) |
37d81828 | 5275 | return -EINVAL; |
7b732a75 PZ |
5276 | |
5277 | vma_size = vma->vm_end - vma->vm_start; | |
45bfb2e5 PZ |
5278 | |
5279 | if (vma->vm_pgoff == 0) { | |
5280 | nr_pages = (vma_size / PAGE_SIZE) - 1; | |
5281 | } else { | |
5282 | /* | |
5283 | * AUX area mapping: if rb->aux_nr_pages != 0, it's already | |
5284 | * mapped, all subsequent mappings should have the same size | |
5285 | * and offset. Must be above the normal perf buffer. | |
5286 | */ | |
5287 | u64 aux_offset, aux_size; | |
5288 | ||
5289 | if (!event->rb) | |
5290 | return -EINVAL; | |
5291 | ||
5292 | nr_pages = vma_size / PAGE_SIZE; | |
5293 | ||
5294 | mutex_lock(&event->mmap_mutex); | |
5295 | ret = -EINVAL; | |
5296 | ||
5297 | rb = event->rb; | |
5298 | if (!rb) | |
5299 | goto aux_unlock; | |
5300 | ||
6aa7de05 MR |
5301 | aux_offset = READ_ONCE(rb->user_page->aux_offset); |
5302 | aux_size = READ_ONCE(rb->user_page->aux_size); | |
45bfb2e5 PZ |
5303 | |
5304 | if (aux_offset < perf_data_size(rb) + PAGE_SIZE) | |
5305 | goto aux_unlock; | |
5306 | ||
5307 | if (aux_offset != vma->vm_pgoff << PAGE_SHIFT) | |
5308 | goto aux_unlock; | |
5309 | ||
5310 | /* already mapped with a different offset */ | |
5311 | if (rb_has_aux(rb) && rb->aux_pgoff != vma->vm_pgoff) | |
5312 | goto aux_unlock; | |
5313 | ||
5314 | if (aux_size != vma_size || aux_size != nr_pages * PAGE_SIZE) | |
5315 | goto aux_unlock; | |
5316 | ||
5317 | /* already mapped with a different size */ | |
5318 | if (rb_has_aux(rb) && rb->aux_nr_pages != nr_pages) | |
5319 | goto aux_unlock; | |
5320 | ||
5321 | if (!is_power_of_2(nr_pages)) | |
5322 | goto aux_unlock; | |
5323 | ||
5324 | if (!atomic_inc_not_zero(&rb->mmap_count)) | |
5325 | goto aux_unlock; | |
5326 | ||
5327 | if (rb_has_aux(rb)) { | |
5328 | atomic_inc(&rb->aux_mmap_count); | |
5329 | ret = 0; | |
5330 | goto unlock; | |
5331 | } | |
5332 | ||
5333 | atomic_set(&rb->aux_mmap_count, 1); | |
5334 | user_extra = nr_pages; | |
5335 | ||
5336 | goto accounting; | |
5337 | } | |
7b732a75 | 5338 | |
7730d865 | 5339 | /* |
76369139 | 5340 | * If we have rb pages ensure they're a power-of-two number, so we |
7730d865 PZ |
5341 | * can do bitmasks instead of modulo. |
5342 | */ | |
2ed11312 | 5343 | if (nr_pages != 0 && !is_power_of_2(nr_pages)) |
37d81828 PM |
5344 | return -EINVAL; |
5345 | ||
7b732a75 | 5346 | if (vma_size != PAGE_SIZE * (1 + nr_pages)) |
37d81828 PM |
5347 | return -EINVAL; |
5348 | ||
cdd6c482 | 5349 | WARN_ON_ONCE(event->ctx->parent_ctx); |
9bb5d40c | 5350 | again: |
cdd6c482 | 5351 | mutex_lock(&event->mmap_mutex); |
76369139 | 5352 | if (event->rb) { |
9bb5d40c | 5353 | if (event->rb->nr_pages != nr_pages) { |
ebb3c4c4 | 5354 | ret = -EINVAL; |
9bb5d40c PZ |
5355 | goto unlock; |
5356 | } | |
5357 | ||
5358 | if (!atomic_inc_not_zero(&event->rb->mmap_count)) { | |
5359 | /* | |
5360 | * Raced against perf_mmap_close() through | |
5361 | * perf_event_set_output(). Try again, hope for better | |
5362 | * luck. | |
5363 | */ | |
5364 | mutex_unlock(&event->mmap_mutex); | |
5365 | goto again; | |
5366 | } | |
5367 | ||
ebb3c4c4 PZ |
5368 | goto unlock; |
5369 | } | |
5370 | ||
789f90fc | 5371 | user_extra = nr_pages + 1; |
45bfb2e5 PZ |
5372 | |
5373 | accounting: | |
cdd6c482 | 5374 | user_lock_limit = sysctl_perf_event_mlock >> (PAGE_SHIFT - 10); |
a3862d3f IM |
5375 | |
5376 | /* | |
5377 | * Increase the limit linearly with more CPUs: | |
5378 | */ | |
5379 | user_lock_limit *= num_online_cpus(); | |
5380 | ||
789f90fc | 5381 | user_locked = atomic_long_read(&user->locked_vm) + user_extra; |
c5078f78 | 5382 | |
789f90fc PZ |
5383 | if (user_locked > user_lock_limit) |
5384 | extra = user_locked - user_lock_limit; | |
7b732a75 | 5385 | |
78d7d407 | 5386 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
7b732a75 | 5387 | lock_limit >>= PAGE_SHIFT; |
bc3e53f6 | 5388 | locked = vma->vm_mm->pinned_vm + extra; |
7b732a75 | 5389 | |
459ec28a IM |
5390 | if ((locked > lock_limit) && perf_paranoid_tracepoint_raw() && |
5391 | !capable(CAP_IPC_LOCK)) { | |
ebb3c4c4 PZ |
5392 | ret = -EPERM; |
5393 | goto unlock; | |
5394 | } | |
7b732a75 | 5395 | |
45bfb2e5 | 5396 | WARN_ON(!rb && event->rb); |
906010b2 | 5397 | |
d57e34fd | 5398 | if (vma->vm_flags & VM_WRITE) |
76369139 | 5399 | flags |= RING_BUFFER_WRITABLE; |
d57e34fd | 5400 | |
76369139 | 5401 | if (!rb) { |
45bfb2e5 PZ |
5402 | rb = rb_alloc(nr_pages, |
5403 | event->attr.watermark ? event->attr.wakeup_watermark : 0, | |
5404 | event->cpu, flags); | |
26cb63ad | 5405 | |
45bfb2e5 PZ |
5406 | if (!rb) { |
5407 | ret = -ENOMEM; | |
5408 | goto unlock; | |
5409 | } | |
43a21ea8 | 5410 | |
45bfb2e5 PZ |
5411 | atomic_set(&rb->mmap_count, 1); |
5412 | rb->mmap_user = get_current_user(); | |
5413 | rb->mmap_locked = extra; | |
26cb63ad | 5414 | |
45bfb2e5 | 5415 | ring_buffer_attach(event, rb); |
ac9721f3 | 5416 | |
45bfb2e5 PZ |
5417 | perf_event_init_userpage(event); |
5418 | perf_event_update_userpage(event); | |
5419 | } else { | |
1a594131 AS |
5420 | ret = rb_alloc_aux(rb, event, vma->vm_pgoff, nr_pages, |
5421 | event->attr.aux_watermark, flags); | |
45bfb2e5 PZ |
5422 | if (!ret) |
5423 | rb->aux_mmap_locked = extra; | |
5424 | } | |
9a0f05cb | 5425 | |
ebb3c4c4 | 5426 | unlock: |
45bfb2e5 PZ |
5427 | if (!ret) { |
5428 | atomic_long_add(user_extra, &user->locked_vm); | |
5429 | vma->vm_mm->pinned_vm += extra; | |
5430 | ||
ac9721f3 | 5431 | atomic_inc(&event->mmap_count); |
45bfb2e5 PZ |
5432 | } else if (rb) { |
5433 | atomic_dec(&rb->mmap_count); | |
5434 | } | |
5435 | aux_unlock: | |
cdd6c482 | 5436 | mutex_unlock(&event->mmap_mutex); |
37d81828 | 5437 | |
9bb5d40c PZ |
5438 | /* |
5439 | * Since pinned accounting is per vm we cannot allow fork() to copy our | |
5440 | * vma. | |
5441 | */ | |
26cb63ad | 5442 | vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND | VM_DONTDUMP; |
37d81828 | 5443 | vma->vm_ops = &perf_mmap_vmops; |
7b732a75 | 5444 | |
1e0fb9ec | 5445 | if (event->pmu->event_mapped) |
bfe33492 | 5446 | event->pmu->event_mapped(event, vma->vm_mm); |
1e0fb9ec | 5447 | |
7b732a75 | 5448 | return ret; |
37d81828 PM |
5449 | } |
5450 | ||
3c446b3d PZ |
5451 | static int perf_fasync(int fd, struct file *filp, int on) |
5452 | { | |
496ad9aa | 5453 | struct inode *inode = file_inode(filp); |
cdd6c482 | 5454 | struct perf_event *event = filp->private_data; |
3c446b3d PZ |
5455 | int retval; |
5456 | ||
5955102c | 5457 | inode_lock(inode); |
cdd6c482 | 5458 | retval = fasync_helper(fd, filp, on, &event->fasync); |
5955102c | 5459 | inode_unlock(inode); |
3c446b3d PZ |
5460 | |
5461 | if (retval < 0) | |
5462 | return retval; | |
5463 | ||
5464 | return 0; | |
5465 | } | |
5466 | ||
0793a61d | 5467 | static const struct file_operations perf_fops = { |
3326c1ce | 5468 | .llseek = no_llseek, |
0793a61d TG |
5469 | .release = perf_release, |
5470 | .read = perf_read, | |
5471 | .poll = perf_poll, | |
d859e29f | 5472 | .unlocked_ioctl = perf_ioctl, |
b3f20785 | 5473 | .compat_ioctl = perf_compat_ioctl, |
37d81828 | 5474 | .mmap = perf_mmap, |
3c446b3d | 5475 | .fasync = perf_fasync, |
0793a61d TG |
5476 | }; |
5477 | ||
925d519a | 5478 | /* |
cdd6c482 | 5479 | * Perf event wakeup |
925d519a PZ |
5480 | * |
5481 | * If there's data, ensure we set the poll() state and publish everything | |
5482 | * to user-space before waking everybody up. | |
5483 | */ | |
5484 | ||
fed66e2c PZ |
5485 | static inline struct fasync_struct **perf_event_fasync(struct perf_event *event) |
5486 | { | |
5487 | /* only the parent has fasync state */ | |
5488 | if (event->parent) | |
5489 | event = event->parent; | |
5490 | return &event->fasync; | |
5491 | } | |
5492 | ||
cdd6c482 | 5493 | void perf_event_wakeup(struct perf_event *event) |
925d519a | 5494 | { |
10c6db11 | 5495 | ring_buffer_wakeup(event); |
4c9e2542 | 5496 | |
cdd6c482 | 5497 | if (event->pending_kill) { |
fed66e2c | 5498 | kill_fasync(perf_event_fasync(event), SIGIO, event->pending_kill); |
cdd6c482 | 5499 | event->pending_kill = 0; |
4c9e2542 | 5500 | } |
925d519a PZ |
5501 | } |
5502 | ||
ac69b885 PZ |
5503 | static void perf_pending_event_disable(struct perf_event *event) |
5504 | { | |
5505 | int cpu = READ_ONCE(event->pending_disable); | |
5506 | ||
5507 | if (cpu < 0) | |
5508 | return; | |
5509 | ||
5510 | if (cpu == smp_processor_id()) { | |
5511 | WRITE_ONCE(event->pending_disable, -1); | |
5512 | perf_event_disable_local(event); | |
5513 | return; | |
5514 | } | |
5515 | ||
5516 | /* | |
5517 | * CPU-A CPU-B | |
5518 | * | |
5519 | * perf_event_disable_inatomic() | |
5520 | * @pending_disable = CPU-A; | |
5521 | * irq_work_queue(); | |
5522 | * | |
5523 | * sched-out | |
5524 | * @pending_disable = -1; | |
5525 | * | |
5526 | * sched-in | |
5527 | * perf_event_disable_inatomic() | |
5528 | * @pending_disable = CPU-B; | |
5529 | * irq_work_queue(); // FAILS | |
5530 | * | |
5531 | * irq_work_run() | |
5532 | * perf_pending_event() | |
5533 | * | |
5534 | * But the event runs on CPU-B and wants disabling there. | |
5535 | */ | |
5536 | irq_work_queue_on(&event->pending, cpu); | |
5537 | } | |
5538 | ||
e360adbe | 5539 | static void perf_pending_event(struct irq_work *entry) |
79f14641 | 5540 | { |
ac69b885 | 5541 | struct perf_event *event = container_of(entry, struct perf_event, pending); |
d525211f PZ |
5542 | int rctx; |
5543 | ||
5544 | rctx = perf_swevent_get_recursion_context(); | |
5545 | /* | |
5546 | * If we 'fail' here, that's OK, it means recursion is already disabled | |
5547 | * and we won't recurse 'further'. | |
5548 | */ | |
79f14641 | 5549 | |
ac69b885 | 5550 | perf_pending_event_disable(event); |
79f14641 | 5551 | |
cdd6c482 IM |
5552 | if (event->pending_wakeup) { |
5553 | event->pending_wakeup = 0; | |
5554 | perf_event_wakeup(event); | |
79f14641 | 5555 | } |
d525211f PZ |
5556 | |
5557 | if (rctx >= 0) | |
5558 | perf_swevent_put_recursion_context(rctx); | |
79f14641 PZ |
5559 | } |
5560 | ||
39447b38 ZY |
5561 | /* |
5562 | * We assume there is only KVM supporting the callbacks. | |
5563 | * Later on, we might change it to a list if there is | |
5564 | * another virtualization implementation supporting the callbacks. | |
5565 | */ | |
5566 | struct perf_guest_info_callbacks *perf_guest_cbs; | |
5567 | ||
5568 | int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
5569 | { | |
5570 | perf_guest_cbs = cbs; | |
5571 | return 0; | |
5572 | } | |
5573 | EXPORT_SYMBOL_GPL(perf_register_guest_info_callbacks); | |
5574 | ||
5575 | int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
5576 | { | |
5577 | perf_guest_cbs = NULL; | |
5578 | return 0; | |
5579 | } | |
5580 | EXPORT_SYMBOL_GPL(perf_unregister_guest_info_callbacks); | |
5581 | ||
4018994f JO |
5582 | static void |
5583 | perf_output_sample_regs(struct perf_output_handle *handle, | |
5584 | struct pt_regs *regs, u64 mask) | |
5585 | { | |
5586 | int bit; | |
29dd3288 | 5587 | DECLARE_BITMAP(_mask, 64); |
4018994f | 5588 | |
29dd3288 MS |
5589 | bitmap_from_u64(_mask, mask); |
5590 | for_each_set_bit(bit, _mask, sizeof(mask) * BITS_PER_BYTE) { | |
4018994f JO |
5591 | u64 val; |
5592 | ||
5593 | val = perf_reg_value(regs, bit); | |
5594 | perf_output_put(handle, val); | |
5595 | } | |
5596 | } | |
5597 | ||
60e2364e | 5598 | static void perf_sample_regs_user(struct perf_regs *regs_user, |
88a7c26a AL |
5599 | struct pt_regs *regs, |
5600 | struct pt_regs *regs_user_copy) | |
4018994f | 5601 | { |
88a7c26a AL |
5602 | if (user_mode(regs)) { |
5603 | regs_user->abi = perf_reg_abi(current); | |
2565711f | 5604 | regs_user->regs = regs; |
193ee4b0 | 5605 | } else if (!(current->flags & PF_KTHREAD)) { |
88a7c26a | 5606 | perf_get_regs_user(regs_user, regs, regs_user_copy); |
2565711f PZ |
5607 | } else { |
5608 | regs_user->abi = PERF_SAMPLE_REGS_ABI_NONE; | |
5609 | regs_user->regs = NULL; | |
4018994f JO |
5610 | } |
5611 | } | |
5612 | ||
60e2364e SE |
5613 | static void perf_sample_regs_intr(struct perf_regs *regs_intr, |
5614 | struct pt_regs *regs) | |
5615 | { | |
5616 | regs_intr->regs = regs; | |
5617 | regs_intr->abi = perf_reg_abi(current); | |
5618 | } | |
5619 | ||
5620 | ||
c5ebcedb JO |
5621 | /* |
5622 | * Get remaining task size from user stack pointer. | |
5623 | * | |
5624 | * It'd be better to take stack vma map and limit this more | |
5625 | * precisly, but there's no way to get it safely under interrupt, | |
5626 | * so using TASK_SIZE as limit. | |
5627 | */ | |
5628 | static u64 perf_ustack_task_size(struct pt_regs *regs) | |
5629 | { | |
5630 | unsigned long addr = perf_user_stack_pointer(regs); | |
5631 | ||
5632 | if (!addr || addr >= TASK_SIZE) | |
5633 | return 0; | |
5634 | ||
5635 | return TASK_SIZE - addr; | |
5636 | } | |
5637 | ||
5638 | static u16 | |
5639 | perf_sample_ustack_size(u16 stack_size, u16 header_size, | |
5640 | struct pt_regs *regs) | |
5641 | { | |
5642 | u64 task_size; | |
5643 | ||
5644 | /* No regs, no stack pointer, no dump. */ | |
5645 | if (!regs) | |
5646 | return 0; | |
5647 | ||
5648 | /* | |
5649 | * Check if we fit in with the requested stack size into the: | |
5650 | * - TASK_SIZE | |
5651 | * If we don't, we limit the size to the TASK_SIZE. | |
5652 | * | |
5653 | * - remaining sample size | |
5654 | * If we don't, we customize the stack size to | |
5655 | * fit in to the remaining sample size. | |
5656 | */ | |
5657 | ||
5658 | task_size = min((u64) USHRT_MAX, perf_ustack_task_size(regs)); | |
5659 | stack_size = min(stack_size, (u16) task_size); | |
5660 | ||
5661 | /* Current header size plus static size and dynamic size. */ | |
5662 | header_size += 2 * sizeof(u64); | |
5663 | ||
5664 | /* Do we fit in with the current stack dump size? */ | |
5665 | if ((u16) (header_size + stack_size) < header_size) { | |
5666 | /* | |
5667 | * If we overflow the maximum size for the sample, | |
5668 | * we customize the stack dump size to fit in. | |
5669 | */ | |
5670 | stack_size = USHRT_MAX - header_size - sizeof(u64); | |
5671 | stack_size = round_up(stack_size, sizeof(u64)); | |
5672 | } | |
5673 | ||
5674 | return stack_size; | |
5675 | } | |
5676 | ||
5677 | static void | |
5678 | perf_output_sample_ustack(struct perf_output_handle *handle, u64 dump_size, | |
5679 | struct pt_regs *regs) | |
5680 | { | |
5681 | /* Case of a kernel thread, nothing to dump */ | |
5682 | if (!regs) { | |
5683 | u64 size = 0; | |
5684 | perf_output_put(handle, size); | |
5685 | } else { | |
5686 | unsigned long sp; | |
5687 | unsigned int rem; | |
5688 | u64 dyn_size; | |
7ae22eb7 | 5689 | mm_segment_t fs; |
c5ebcedb JO |
5690 | |
5691 | /* | |
5692 | * We dump: | |
5693 | * static size | |
5694 | * - the size requested by user or the best one we can fit | |
5695 | * in to the sample max size | |
5696 | * data | |
5697 | * - user stack dump data | |
5698 | * dynamic size | |
5699 | * - the actual dumped size | |
5700 | */ | |
5701 | ||
5702 | /* Static size. */ | |
5703 | perf_output_put(handle, dump_size); | |
5704 | ||
5705 | /* Data. */ | |
5706 | sp = perf_user_stack_pointer(regs); | |
7ae22eb7 YC |
5707 | fs = get_fs(); |
5708 | set_fs(USER_DS); | |
c5ebcedb | 5709 | rem = __output_copy_user(handle, (void *) sp, dump_size); |
7ae22eb7 | 5710 | set_fs(fs); |
c5ebcedb JO |
5711 | dyn_size = dump_size - rem; |
5712 | ||
5713 | perf_output_skip(handle, rem); | |
5714 | ||
5715 | /* Dynamic size. */ | |
5716 | perf_output_put(handle, dyn_size); | |
5717 | } | |
5718 | } | |
5719 | ||
c980d109 ACM |
5720 | static void __perf_event_header__init_id(struct perf_event_header *header, |
5721 | struct perf_sample_data *data, | |
5722 | struct perf_event *event) | |
6844c09d ACM |
5723 | { |
5724 | u64 sample_type = event->attr.sample_type; | |
5725 | ||
5726 | data->type = sample_type; | |
5727 | header->size += event->id_header_size; | |
5728 | ||
5729 | if (sample_type & PERF_SAMPLE_TID) { | |
5730 | /* namespace issues */ | |
5731 | data->tid_entry.pid = perf_event_pid(event, current); | |
5732 | data->tid_entry.tid = perf_event_tid(event, current); | |
5733 | } | |
5734 | ||
5735 | if (sample_type & PERF_SAMPLE_TIME) | |
34f43927 | 5736 | data->time = perf_event_clock(event); |
6844c09d | 5737 | |
ff3d527c | 5738 | if (sample_type & (PERF_SAMPLE_ID | PERF_SAMPLE_IDENTIFIER)) |
6844c09d ACM |
5739 | data->id = primary_event_id(event); |
5740 | ||
5741 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
5742 | data->stream_id = event->id; | |
5743 | ||
5744 | if (sample_type & PERF_SAMPLE_CPU) { | |
5745 | data->cpu_entry.cpu = raw_smp_processor_id(); | |
5746 | data->cpu_entry.reserved = 0; | |
5747 | } | |
5748 | } | |
5749 | ||
76369139 FW |
5750 | void perf_event_header__init_id(struct perf_event_header *header, |
5751 | struct perf_sample_data *data, | |
5752 | struct perf_event *event) | |
c980d109 ACM |
5753 | { |
5754 | if (event->attr.sample_id_all) | |
5755 | __perf_event_header__init_id(header, data, event); | |
5756 | } | |
5757 | ||
5758 | static void __perf_event__output_id_sample(struct perf_output_handle *handle, | |
5759 | struct perf_sample_data *data) | |
5760 | { | |
5761 | u64 sample_type = data->type; | |
5762 | ||
5763 | if (sample_type & PERF_SAMPLE_TID) | |
5764 | perf_output_put(handle, data->tid_entry); | |
5765 | ||
5766 | if (sample_type & PERF_SAMPLE_TIME) | |
5767 | perf_output_put(handle, data->time); | |
5768 | ||
5769 | if (sample_type & PERF_SAMPLE_ID) | |
5770 | perf_output_put(handle, data->id); | |
5771 | ||
5772 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
5773 | perf_output_put(handle, data->stream_id); | |
5774 | ||
5775 | if (sample_type & PERF_SAMPLE_CPU) | |
5776 | perf_output_put(handle, data->cpu_entry); | |
ff3d527c AH |
5777 | |
5778 | if (sample_type & PERF_SAMPLE_IDENTIFIER) | |
5779 | perf_output_put(handle, data->id); | |
c980d109 ACM |
5780 | } |
5781 | ||
76369139 FW |
5782 | void perf_event__output_id_sample(struct perf_event *event, |
5783 | struct perf_output_handle *handle, | |
5784 | struct perf_sample_data *sample) | |
c980d109 ACM |
5785 | { |
5786 | if (event->attr.sample_id_all) | |
5787 | __perf_event__output_id_sample(handle, sample); | |
5788 | } | |
5789 | ||
3dab77fb | 5790 | static void perf_output_read_one(struct perf_output_handle *handle, |
eed01528 SE |
5791 | struct perf_event *event, |
5792 | u64 enabled, u64 running) | |
3dab77fb | 5793 | { |
cdd6c482 | 5794 | u64 read_format = event->attr.read_format; |
3dab77fb PZ |
5795 | u64 values[4]; |
5796 | int n = 0; | |
5797 | ||
b5e58793 | 5798 | values[n++] = perf_event_count(event); |
3dab77fb | 5799 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { |
eed01528 | 5800 | values[n++] = enabled + |
cdd6c482 | 5801 | atomic64_read(&event->child_total_time_enabled); |
3dab77fb PZ |
5802 | } |
5803 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { | |
eed01528 | 5804 | values[n++] = running + |
cdd6c482 | 5805 | atomic64_read(&event->child_total_time_running); |
3dab77fb PZ |
5806 | } |
5807 | if (read_format & PERF_FORMAT_ID) | |
cdd6c482 | 5808 | values[n++] = primary_event_id(event); |
3dab77fb | 5809 | |
76369139 | 5810 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
5811 | } |
5812 | ||
3dab77fb | 5813 | static void perf_output_read_group(struct perf_output_handle *handle, |
eed01528 SE |
5814 | struct perf_event *event, |
5815 | u64 enabled, u64 running) | |
3dab77fb | 5816 | { |
cdd6c482 IM |
5817 | struct perf_event *leader = event->group_leader, *sub; |
5818 | u64 read_format = event->attr.read_format; | |
3dab77fb PZ |
5819 | u64 values[5]; |
5820 | int n = 0; | |
5821 | ||
5822 | values[n++] = 1 + leader->nr_siblings; | |
5823 | ||
5824 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
eed01528 | 5825 | values[n++] = enabled; |
3dab77fb PZ |
5826 | |
5827 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
eed01528 | 5828 | values[n++] = running; |
3dab77fb | 5829 | |
e24bcd5a PZ |
5830 | if ((leader != event) && |
5831 | (leader->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
5832 | leader->pmu->read(leader); |
5833 | ||
b5e58793 | 5834 | values[n++] = perf_event_count(leader); |
3dab77fb | 5835 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 5836 | values[n++] = primary_event_id(leader); |
3dab77fb | 5837 | |
76369139 | 5838 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb | 5839 | |
65abc865 | 5840 | list_for_each_entry(sub, &leader->sibling_list, group_entry) { |
3dab77fb PZ |
5841 | n = 0; |
5842 | ||
6f5ab001 JO |
5843 | if ((sub != event) && |
5844 | (sub->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
5845 | sub->pmu->read(sub); |
5846 | ||
b5e58793 | 5847 | values[n++] = perf_event_count(sub); |
3dab77fb | 5848 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 5849 | values[n++] = primary_event_id(sub); |
3dab77fb | 5850 | |
76369139 | 5851 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
5852 | } |
5853 | } | |
5854 | ||
eed01528 SE |
5855 | #define PERF_FORMAT_TOTAL_TIMES (PERF_FORMAT_TOTAL_TIME_ENABLED|\ |
5856 | PERF_FORMAT_TOTAL_TIME_RUNNING) | |
5857 | ||
ba5213ae PZ |
5858 | /* |
5859 | * XXX PERF_SAMPLE_READ vs inherited events seems difficult. | |
5860 | * | |
5861 | * The problem is that its both hard and excessively expensive to iterate the | |
5862 | * child list, not to mention that its impossible to IPI the children running | |
5863 | * on another CPU, from interrupt/NMI context. | |
5864 | */ | |
3dab77fb | 5865 | static void perf_output_read(struct perf_output_handle *handle, |
cdd6c482 | 5866 | struct perf_event *event) |
3dab77fb | 5867 | { |
e3f3541c | 5868 | u64 enabled = 0, running = 0, now; |
eed01528 SE |
5869 | u64 read_format = event->attr.read_format; |
5870 | ||
5871 | /* | |
5872 | * compute total_time_enabled, total_time_running | |
5873 | * based on snapshot values taken when the event | |
5874 | * was last scheduled in. | |
5875 | * | |
5876 | * we cannot simply called update_context_time() | |
5877 | * because of locking issue as we are called in | |
5878 | * NMI context | |
5879 | */ | |
c4794295 | 5880 | if (read_format & PERF_FORMAT_TOTAL_TIMES) |
e3f3541c | 5881 | calc_timer_values(event, &now, &enabled, &running); |
eed01528 | 5882 | |
cdd6c482 | 5883 | if (event->attr.read_format & PERF_FORMAT_GROUP) |
eed01528 | 5884 | perf_output_read_group(handle, event, enabled, running); |
3dab77fb | 5885 | else |
eed01528 | 5886 | perf_output_read_one(handle, event, enabled, running); |
3dab77fb PZ |
5887 | } |
5888 | ||
5622f295 MM |
5889 | void perf_output_sample(struct perf_output_handle *handle, |
5890 | struct perf_event_header *header, | |
5891 | struct perf_sample_data *data, | |
cdd6c482 | 5892 | struct perf_event *event) |
5622f295 MM |
5893 | { |
5894 | u64 sample_type = data->type; | |
5895 | ||
5896 | perf_output_put(handle, *header); | |
5897 | ||
ff3d527c AH |
5898 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
5899 | perf_output_put(handle, data->id); | |
5900 | ||
5622f295 MM |
5901 | if (sample_type & PERF_SAMPLE_IP) |
5902 | perf_output_put(handle, data->ip); | |
5903 | ||
5904 | if (sample_type & PERF_SAMPLE_TID) | |
5905 | perf_output_put(handle, data->tid_entry); | |
5906 | ||
5907 | if (sample_type & PERF_SAMPLE_TIME) | |
5908 | perf_output_put(handle, data->time); | |
5909 | ||
5910 | if (sample_type & PERF_SAMPLE_ADDR) | |
5911 | perf_output_put(handle, data->addr); | |
5912 | ||
5913 | if (sample_type & PERF_SAMPLE_ID) | |
5914 | perf_output_put(handle, data->id); | |
5915 | ||
5916 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
5917 | perf_output_put(handle, data->stream_id); | |
5918 | ||
5919 | if (sample_type & PERF_SAMPLE_CPU) | |
5920 | perf_output_put(handle, data->cpu_entry); | |
5921 | ||
5922 | if (sample_type & PERF_SAMPLE_PERIOD) | |
5923 | perf_output_put(handle, data->period); | |
5924 | ||
5925 | if (sample_type & PERF_SAMPLE_READ) | |
cdd6c482 | 5926 | perf_output_read(handle, event); |
5622f295 MM |
5927 | |
5928 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { | |
5929 | if (data->callchain) { | |
5930 | int size = 1; | |
5931 | ||
5932 | if (data->callchain) | |
5933 | size += data->callchain->nr; | |
5934 | ||
5935 | size *= sizeof(u64); | |
5936 | ||
76369139 | 5937 | __output_copy(handle, data->callchain, size); |
5622f295 MM |
5938 | } else { |
5939 | u64 nr = 0; | |
5940 | perf_output_put(handle, nr); | |
5941 | } | |
5942 | } | |
5943 | ||
5944 | if (sample_type & PERF_SAMPLE_RAW) { | |
7e3f977e DB |
5945 | struct perf_raw_record *raw = data->raw; |
5946 | ||
5947 | if (raw) { | |
5948 | struct perf_raw_frag *frag = &raw->frag; | |
5949 | ||
5950 | perf_output_put(handle, raw->size); | |
5951 | do { | |
5952 | if (frag->copy) { | |
5953 | __output_custom(handle, frag->copy, | |
5954 | frag->data, frag->size); | |
5955 | } else { | |
5956 | __output_copy(handle, frag->data, | |
5957 | frag->size); | |
5958 | } | |
5959 | if (perf_raw_frag_last(frag)) | |
5960 | break; | |
5961 | frag = frag->next; | |
5962 | } while (1); | |
5963 | if (frag->pad) | |
5964 | __output_skip(handle, NULL, frag->pad); | |
5622f295 MM |
5965 | } else { |
5966 | struct { | |
5967 | u32 size; | |
5968 | u32 data; | |
5969 | } raw = { | |
5970 | .size = sizeof(u32), | |
5971 | .data = 0, | |
5972 | }; | |
5973 | perf_output_put(handle, raw); | |
5974 | } | |
5975 | } | |
a7ac67ea | 5976 | |
bce38cd5 SE |
5977 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { |
5978 | if (data->br_stack) { | |
5979 | size_t size; | |
5980 | ||
5981 | size = data->br_stack->nr | |
5982 | * sizeof(struct perf_branch_entry); | |
5983 | ||
5984 | perf_output_put(handle, data->br_stack->nr); | |
5985 | perf_output_copy(handle, data->br_stack->entries, size); | |
5986 | } else { | |
5987 | /* | |
5988 | * we always store at least the value of nr | |
5989 | */ | |
5990 | u64 nr = 0; | |
5991 | perf_output_put(handle, nr); | |
5992 | } | |
5993 | } | |
4018994f JO |
5994 | |
5995 | if (sample_type & PERF_SAMPLE_REGS_USER) { | |
5996 | u64 abi = data->regs_user.abi; | |
5997 | ||
5998 | /* | |
5999 | * If there are no regs to dump, notice it through | |
6000 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
6001 | */ | |
6002 | perf_output_put(handle, abi); | |
6003 | ||
6004 | if (abi) { | |
6005 | u64 mask = event->attr.sample_regs_user; | |
6006 | perf_output_sample_regs(handle, | |
6007 | data->regs_user.regs, | |
6008 | mask); | |
6009 | } | |
6010 | } | |
c5ebcedb | 6011 | |
a5cdd40c | 6012 | if (sample_type & PERF_SAMPLE_STACK_USER) { |
c5ebcedb JO |
6013 | perf_output_sample_ustack(handle, |
6014 | data->stack_user_size, | |
6015 | data->regs_user.regs); | |
a5cdd40c | 6016 | } |
c3feedf2 AK |
6017 | |
6018 | if (sample_type & PERF_SAMPLE_WEIGHT) | |
6019 | perf_output_put(handle, data->weight); | |
d6be9ad6 SE |
6020 | |
6021 | if (sample_type & PERF_SAMPLE_DATA_SRC) | |
6022 | perf_output_put(handle, data->data_src.val); | |
a5cdd40c | 6023 | |
fdfbbd07 AK |
6024 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
6025 | perf_output_put(handle, data->txn); | |
6026 | ||
60e2364e SE |
6027 | if (sample_type & PERF_SAMPLE_REGS_INTR) { |
6028 | u64 abi = data->regs_intr.abi; | |
6029 | /* | |
6030 | * If there are no regs to dump, notice it through | |
6031 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
6032 | */ | |
6033 | perf_output_put(handle, abi); | |
6034 | ||
6035 | if (abi) { | |
6036 | u64 mask = event->attr.sample_regs_intr; | |
6037 | ||
6038 | perf_output_sample_regs(handle, | |
6039 | data->regs_intr.regs, | |
6040 | mask); | |
6041 | } | |
6042 | } | |
6043 | ||
fc7ce9c7 KL |
6044 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) |
6045 | perf_output_put(handle, data->phys_addr); | |
6046 | ||
a5cdd40c PZ |
6047 | if (!event->attr.watermark) { |
6048 | int wakeup_events = event->attr.wakeup_events; | |
6049 | ||
6050 | if (wakeup_events) { | |
6051 | struct ring_buffer *rb = handle->rb; | |
6052 | int events = local_inc_return(&rb->events); | |
6053 | ||
6054 | if (events >= wakeup_events) { | |
6055 | local_sub(wakeup_events, &rb->events); | |
6056 | local_inc(&rb->wakeup); | |
6057 | } | |
6058 | } | |
6059 | } | |
5622f295 MM |
6060 | } |
6061 | ||
fc7ce9c7 KL |
6062 | static u64 perf_virt_to_phys(u64 virt) |
6063 | { | |
6064 | u64 phys_addr = 0; | |
6065 | struct page *p = NULL; | |
6066 | ||
6067 | if (!virt) | |
6068 | return 0; | |
6069 | ||
6070 | if (virt >= TASK_SIZE) { | |
6071 | /* If it's vmalloc()d memory, leave phys_addr as 0 */ | |
6072 | if (virt_addr_valid((void *)(uintptr_t)virt) && | |
6073 | !(virt >= VMALLOC_START && virt < VMALLOC_END)) | |
6074 | phys_addr = (u64)virt_to_phys((void *)(uintptr_t)virt); | |
6075 | } else { | |
6076 | /* | |
6077 | * Walking the pages tables for user address. | |
6078 | * Interrupts are disabled, so it prevents any tear down | |
6079 | * of the page tables. | |
6080 | * Try IRQ-safe __get_user_pages_fast first. | |
6081 | * If failed, leave phys_addr as 0. | |
6082 | */ | |
6083 | if ((current->mm != NULL) && | |
6084 | (__get_user_pages_fast(virt, 1, 0, &p) == 1)) | |
6085 | phys_addr = page_to_phys(p) + virt % PAGE_SIZE; | |
6086 | ||
6087 | if (p) | |
6088 | put_page(p); | |
6089 | } | |
6090 | ||
6091 | return phys_addr; | |
6092 | } | |
6093 | ||
5622f295 MM |
6094 | void perf_prepare_sample(struct perf_event_header *header, |
6095 | struct perf_sample_data *data, | |
cdd6c482 | 6096 | struct perf_event *event, |
5622f295 | 6097 | struct pt_regs *regs) |
7b732a75 | 6098 | { |
cdd6c482 | 6099 | u64 sample_type = event->attr.sample_type; |
7b732a75 | 6100 | |
cdd6c482 | 6101 | header->type = PERF_RECORD_SAMPLE; |
c320c7b7 | 6102 | header->size = sizeof(*header) + event->header_size; |
5622f295 MM |
6103 | |
6104 | header->misc = 0; | |
6105 | header->misc |= perf_misc_flags(regs); | |
6fab0192 | 6106 | |
c980d109 | 6107 | __perf_event_header__init_id(header, data, event); |
6844c09d | 6108 | |
c320c7b7 | 6109 | if (sample_type & PERF_SAMPLE_IP) |
5622f295 MM |
6110 | data->ip = perf_instruction_pointer(regs); |
6111 | ||
b23f3325 | 6112 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { |
5622f295 | 6113 | int size = 1; |
394ee076 | 6114 | |
e6dab5ff | 6115 | data->callchain = perf_callchain(event, regs); |
5622f295 MM |
6116 | |
6117 | if (data->callchain) | |
6118 | size += data->callchain->nr; | |
6119 | ||
6120 | header->size += size * sizeof(u64); | |
394ee076 PZ |
6121 | } |
6122 | ||
3a43ce68 | 6123 | if (sample_type & PERF_SAMPLE_RAW) { |
7e3f977e DB |
6124 | struct perf_raw_record *raw = data->raw; |
6125 | int size; | |
6126 | ||
6127 | if (raw) { | |
6128 | struct perf_raw_frag *frag = &raw->frag; | |
6129 | u32 sum = 0; | |
6130 | ||
6131 | do { | |
6132 | sum += frag->size; | |
6133 | if (perf_raw_frag_last(frag)) | |
6134 | break; | |
6135 | frag = frag->next; | |
6136 | } while (1); | |
6137 | ||
6138 | size = round_up(sum + sizeof(u32), sizeof(u64)); | |
6139 | raw->size = size - sizeof(u32); | |
6140 | frag->pad = raw->size - sum; | |
6141 | } else { | |
6142 | size = sizeof(u64); | |
6143 | } | |
a044560c | 6144 | |
7e3f977e | 6145 | header->size += size; |
7f453c24 | 6146 | } |
bce38cd5 SE |
6147 | |
6148 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { | |
6149 | int size = sizeof(u64); /* nr */ | |
6150 | if (data->br_stack) { | |
6151 | size += data->br_stack->nr | |
6152 | * sizeof(struct perf_branch_entry); | |
6153 | } | |
6154 | header->size += size; | |
6155 | } | |
4018994f | 6156 | |
2565711f | 6157 | if (sample_type & (PERF_SAMPLE_REGS_USER | PERF_SAMPLE_STACK_USER)) |
88a7c26a AL |
6158 | perf_sample_regs_user(&data->regs_user, regs, |
6159 | &data->regs_user_copy); | |
2565711f | 6160 | |
4018994f JO |
6161 | if (sample_type & PERF_SAMPLE_REGS_USER) { |
6162 | /* regs dump ABI info */ | |
6163 | int size = sizeof(u64); | |
6164 | ||
4018994f JO |
6165 | if (data->regs_user.regs) { |
6166 | u64 mask = event->attr.sample_regs_user; | |
6167 | size += hweight64(mask) * sizeof(u64); | |
6168 | } | |
6169 | ||
6170 | header->size += size; | |
6171 | } | |
c5ebcedb JO |
6172 | |
6173 | if (sample_type & PERF_SAMPLE_STACK_USER) { | |
6174 | /* | |
6175 | * Either we need PERF_SAMPLE_STACK_USER bit to be allways | |
6176 | * processed as the last one or have additional check added | |
6177 | * in case new sample type is added, because we could eat | |
6178 | * up the rest of the sample size. | |
6179 | */ | |
c5ebcedb JO |
6180 | u16 stack_size = event->attr.sample_stack_user; |
6181 | u16 size = sizeof(u64); | |
6182 | ||
c5ebcedb | 6183 | stack_size = perf_sample_ustack_size(stack_size, header->size, |
2565711f | 6184 | data->regs_user.regs); |
c5ebcedb JO |
6185 | |
6186 | /* | |
6187 | * If there is something to dump, add space for the dump | |
6188 | * itself and for the field that tells the dynamic size, | |
6189 | * which is how many have been actually dumped. | |
6190 | */ | |
6191 | if (stack_size) | |
6192 | size += sizeof(u64) + stack_size; | |
6193 | ||
6194 | data->stack_user_size = stack_size; | |
6195 | header->size += size; | |
6196 | } | |
60e2364e SE |
6197 | |
6198 | if (sample_type & PERF_SAMPLE_REGS_INTR) { | |
6199 | /* regs dump ABI info */ | |
6200 | int size = sizeof(u64); | |
6201 | ||
6202 | perf_sample_regs_intr(&data->regs_intr, regs); | |
6203 | ||
6204 | if (data->regs_intr.regs) { | |
6205 | u64 mask = event->attr.sample_regs_intr; | |
6206 | ||
6207 | size += hweight64(mask) * sizeof(u64); | |
6208 | } | |
6209 | ||
6210 | header->size += size; | |
6211 | } | |
fc7ce9c7 KL |
6212 | |
6213 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) | |
6214 | data->phys_addr = perf_virt_to_phys(data->addr); | |
5622f295 | 6215 | } |
7f453c24 | 6216 | |
9ecda41a WN |
6217 | static void __always_inline |
6218 | __perf_event_output(struct perf_event *event, | |
6219 | struct perf_sample_data *data, | |
6220 | struct pt_regs *regs, | |
6221 | int (*output_begin)(struct perf_output_handle *, | |
6222 | struct perf_event *, | |
6223 | unsigned int)) | |
5622f295 MM |
6224 | { |
6225 | struct perf_output_handle handle; | |
6226 | struct perf_event_header header; | |
689802b2 | 6227 | |
927c7a9e FW |
6228 | /* protect the callchain buffers */ |
6229 | rcu_read_lock(); | |
6230 | ||
cdd6c482 | 6231 | perf_prepare_sample(&header, data, event, regs); |
5c148194 | 6232 | |
9ecda41a | 6233 | if (output_begin(&handle, event, header.size)) |
927c7a9e | 6234 | goto exit; |
0322cd6e | 6235 | |
cdd6c482 | 6236 | perf_output_sample(&handle, &header, data, event); |
f413cdb8 | 6237 | |
8a057d84 | 6238 | perf_output_end(&handle); |
927c7a9e FW |
6239 | |
6240 | exit: | |
6241 | rcu_read_unlock(); | |
0322cd6e PZ |
6242 | } |
6243 | ||
9ecda41a WN |
6244 | void |
6245 | perf_event_output_forward(struct perf_event *event, | |
6246 | struct perf_sample_data *data, | |
6247 | struct pt_regs *regs) | |
6248 | { | |
6249 | __perf_event_output(event, data, regs, perf_output_begin_forward); | |
6250 | } | |
6251 | ||
6252 | void | |
6253 | perf_event_output_backward(struct perf_event *event, | |
6254 | struct perf_sample_data *data, | |
6255 | struct pt_regs *regs) | |
6256 | { | |
6257 | __perf_event_output(event, data, regs, perf_output_begin_backward); | |
6258 | } | |
6259 | ||
6260 | void | |
6261 | perf_event_output(struct perf_event *event, | |
6262 | struct perf_sample_data *data, | |
6263 | struct pt_regs *regs) | |
6264 | { | |
6265 | __perf_event_output(event, data, regs, perf_output_begin); | |
6266 | } | |
6267 | ||
38b200d6 | 6268 | /* |
cdd6c482 | 6269 | * read event_id |
38b200d6 PZ |
6270 | */ |
6271 | ||
6272 | struct perf_read_event { | |
6273 | struct perf_event_header header; | |
6274 | ||
6275 | u32 pid; | |
6276 | u32 tid; | |
38b200d6 PZ |
6277 | }; |
6278 | ||
6279 | static void | |
cdd6c482 | 6280 | perf_event_read_event(struct perf_event *event, |
38b200d6 PZ |
6281 | struct task_struct *task) |
6282 | { | |
6283 | struct perf_output_handle handle; | |
c980d109 | 6284 | struct perf_sample_data sample; |
dfc65094 | 6285 | struct perf_read_event read_event = { |
38b200d6 | 6286 | .header = { |
cdd6c482 | 6287 | .type = PERF_RECORD_READ, |
38b200d6 | 6288 | .misc = 0, |
c320c7b7 | 6289 | .size = sizeof(read_event) + event->read_size, |
38b200d6 | 6290 | }, |
cdd6c482 IM |
6291 | .pid = perf_event_pid(event, task), |
6292 | .tid = perf_event_tid(event, task), | |
38b200d6 | 6293 | }; |
3dab77fb | 6294 | int ret; |
38b200d6 | 6295 | |
c980d109 | 6296 | perf_event_header__init_id(&read_event.header, &sample, event); |
a7ac67ea | 6297 | ret = perf_output_begin(&handle, event, read_event.header.size); |
38b200d6 PZ |
6298 | if (ret) |
6299 | return; | |
6300 | ||
dfc65094 | 6301 | perf_output_put(&handle, read_event); |
cdd6c482 | 6302 | perf_output_read(&handle, event); |
c980d109 | 6303 | perf_event__output_id_sample(event, &handle, &sample); |
3dab77fb | 6304 | |
38b200d6 PZ |
6305 | perf_output_end(&handle); |
6306 | } | |
6307 | ||
aab5b71e | 6308 | typedef void (perf_iterate_f)(struct perf_event *event, void *data); |
52d857a8 JO |
6309 | |
6310 | static void | |
aab5b71e PZ |
6311 | perf_iterate_ctx(struct perf_event_context *ctx, |
6312 | perf_iterate_f output, | |
b73e4fef | 6313 | void *data, bool all) |
52d857a8 JO |
6314 | { |
6315 | struct perf_event *event; | |
6316 | ||
6317 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
b73e4fef AS |
6318 | if (!all) { |
6319 | if (event->state < PERF_EVENT_STATE_INACTIVE) | |
6320 | continue; | |
6321 | if (!event_filter_match(event)) | |
6322 | continue; | |
6323 | } | |
6324 | ||
67516844 | 6325 | output(event, data); |
52d857a8 JO |
6326 | } |
6327 | } | |
6328 | ||
aab5b71e | 6329 | static void perf_iterate_sb_cpu(perf_iterate_f output, void *data) |
f2fb6bef KL |
6330 | { |
6331 | struct pmu_event_list *pel = this_cpu_ptr(&pmu_sb_events); | |
6332 | struct perf_event *event; | |
6333 | ||
6334 | list_for_each_entry_rcu(event, &pel->list, sb_list) { | |
0b8f1e2e PZ |
6335 | /* |
6336 | * Skip events that are not fully formed yet; ensure that | |
6337 | * if we observe event->ctx, both event and ctx will be | |
6338 | * complete enough. See perf_install_in_context(). | |
6339 | */ | |
6340 | if (!smp_load_acquire(&event->ctx)) | |
6341 | continue; | |
6342 | ||
f2fb6bef KL |
6343 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
6344 | continue; | |
6345 | if (!event_filter_match(event)) | |
6346 | continue; | |
6347 | output(event, data); | |
6348 | } | |
6349 | } | |
6350 | ||
aab5b71e PZ |
6351 | /* |
6352 | * Iterate all events that need to receive side-band events. | |
6353 | * | |
6354 | * For new callers; ensure that account_pmu_sb_event() includes | |
6355 | * your event, otherwise it might not get delivered. | |
6356 | */ | |
52d857a8 | 6357 | static void |
aab5b71e | 6358 | perf_iterate_sb(perf_iterate_f output, void *data, |
52d857a8 JO |
6359 | struct perf_event_context *task_ctx) |
6360 | { | |
52d857a8 | 6361 | struct perf_event_context *ctx; |
52d857a8 JO |
6362 | int ctxn; |
6363 | ||
aab5b71e PZ |
6364 | rcu_read_lock(); |
6365 | preempt_disable(); | |
6366 | ||
4e93ad60 | 6367 | /* |
aab5b71e PZ |
6368 | * If we have task_ctx != NULL we only notify the task context itself. |
6369 | * The task_ctx is set only for EXIT events before releasing task | |
4e93ad60 JO |
6370 | * context. |
6371 | */ | |
6372 | if (task_ctx) { | |
aab5b71e PZ |
6373 | perf_iterate_ctx(task_ctx, output, data, false); |
6374 | goto done; | |
4e93ad60 JO |
6375 | } |
6376 | ||
aab5b71e | 6377 | perf_iterate_sb_cpu(output, data); |
f2fb6bef KL |
6378 | |
6379 | for_each_task_context_nr(ctxn) { | |
52d857a8 JO |
6380 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); |
6381 | if (ctx) | |
aab5b71e | 6382 | perf_iterate_ctx(ctx, output, data, false); |
52d857a8 | 6383 | } |
aab5b71e | 6384 | done: |
f2fb6bef | 6385 | preempt_enable(); |
52d857a8 | 6386 | rcu_read_unlock(); |
95ff4ca2 AS |
6387 | } |
6388 | ||
375637bc AS |
6389 | /* |
6390 | * Clear all file-based filters at exec, they'll have to be | |
6391 | * re-instated when/if these objects are mmapped again. | |
6392 | */ | |
6393 | static void perf_event_addr_filters_exec(struct perf_event *event, void *data) | |
6394 | { | |
6395 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
6396 | struct perf_addr_filter *filter; | |
6397 | unsigned int restart = 0, count = 0; | |
6398 | unsigned long flags; | |
6399 | ||
6400 | if (!has_addr_filter(event)) | |
6401 | return; | |
6402 | ||
6403 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
6404 | list_for_each_entry(filter, &ifh->list, entry) { | |
6405 | if (filter->inode) { | |
6406 | event->addr_filters_offs[count] = 0; | |
6407 | restart++; | |
6408 | } | |
6409 | ||
6410 | count++; | |
6411 | } | |
6412 | ||
6413 | if (restart) | |
6414 | event->addr_filters_gen++; | |
6415 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
6416 | ||
6417 | if (restart) | |
767ae086 | 6418 | perf_event_stop(event, 1); |
375637bc AS |
6419 | } |
6420 | ||
6421 | void perf_event_exec(void) | |
6422 | { | |
6423 | struct perf_event_context *ctx; | |
6424 | int ctxn; | |
6425 | ||
6426 | rcu_read_lock(); | |
6427 | for_each_task_context_nr(ctxn) { | |
6428 | ctx = current->perf_event_ctxp[ctxn]; | |
6429 | if (!ctx) | |
6430 | continue; | |
6431 | ||
6432 | perf_event_enable_on_exec(ctxn); | |
6433 | ||
aab5b71e | 6434 | perf_iterate_ctx(ctx, perf_event_addr_filters_exec, NULL, |
375637bc AS |
6435 | true); |
6436 | } | |
6437 | rcu_read_unlock(); | |
6438 | } | |
6439 | ||
95ff4ca2 AS |
6440 | struct remote_output { |
6441 | struct ring_buffer *rb; | |
6442 | int err; | |
6443 | }; | |
6444 | ||
6445 | static void __perf_event_output_stop(struct perf_event *event, void *data) | |
6446 | { | |
6447 | struct perf_event *parent = event->parent; | |
6448 | struct remote_output *ro = data; | |
6449 | struct ring_buffer *rb = ro->rb; | |
375637bc AS |
6450 | struct stop_event_data sd = { |
6451 | .event = event, | |
6452 | }; | |
95ff4ca2 AS |
6453 | |
6454 | if (!has_aux(event)) | |
6455 | return; | |
6456 | ||
6457 | if (!parent) | |
6458 | parent = event; | |
6459 | ||
6460 | /* | |
6461 | * In case of inheritance, it will be the parent that links to the | |
767ae086 AS |
6462 | * ring-buffer, but it will be the child that's actually using it. |
6463 | * | |
6464 | * We are using event::rb to determine if the event should be stopped, | |
6465 | * however this may race with ring_buffer_attach() (through set_output), | |
6466 | * which will make us skip the event that actually needs to be stopped. | |
6467 | * So ring_buffer_attach() has to stop an aux event before re-assigning | |
6468 | * its rb pointer. | |
95ff4ca2 AS |
6469 | */ |
6470 | if (rcu_dereference(parent->rb) == rb) | |
375637bc | 6471 | ro->err = __perf_event_stop(&sd); |
95ff4ca2 AS |
6472 | } |
6473 | ||
6474 | static int __perf_pmu_output_stop(void *info) | |
6475 | { | |
6476 | struct perf_event *event = info; | |
70f08abe | 6477 | struct pmu *pmu = event->ctx->pmu; |
8b6a3fe8 | 6478 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
95ff4ca2 AS |
6479 | struct remote_output ro = { |
6480 | .rb = event->rb, | |
6481 | }; | |
6482 | ||
6483 | rcu_read_lock(); | |
aab5b71e | 6484 | perf_iterate_ctx(&cpuctx->ctx, __perf_event_output_stop, &ro, false); |
95ff4ca2 | 6485 | if (cpuctx->task_ctx) |
aab5b71e | 6486 | perf_iterate_ctx(cpuctx->task_ctx, __perf_event_output_stop, |
b73e4fef | 6487 | &ro, false); |
95ff4ca2 AS |
6488 | rcu_read_unlock(); |
6489 | ||
6490 | return ro.err; | |
6491 | } | |
6492 | ||
6493 | static void perf_pmu_output_stop(struct perf_event *event) | |
6494 | { | |
6495 | struct perf_event *iter; | |
6496 | int err, cpu; | |
6497 | ||
6498 | restart: | |
6499 | rcu_read_lock(); | |
6500 | list_for_each_entry_rcu(iter, &event->rb->event_list, rb_entry) { | |
6501 | /* | |
6502 | * For per-CPU events, we need to make sure that neither they | |
6503 | * nor their children are running; for cpu==-1 events it's | |
6504 | * sufficient to stop the event itself if it's active, since | |
6505 | * it can't have children. | |
6506 | */ | |
6507 | cpu = iter->cpu; | |
6508 | if (cpu == -1) | |
6509 | cpu = READ_ONCE(iter->oncpu); | |
6510 | ||
6511 | if (cpu == -1) | |
6512 | continue; | |
6513 | ||
6514 | err = cpu_function_call(cpu, __perf_pmu_output_stop, event); | |
6515 | if (err == -EAGAIN) { | |
6516 | rcu_read_unlock(); | |
6517 | goto restart; | |
6518 | } | |
6519 | } | |
6520 | rcu_read_unlock(); | |
52d857a8 JO |
6521 | } |
6522 | ||
60313ebe | 6523 | /* |
9f498cc5 PZ |
6524 | * task tracking -- fork/exit |
6525 | * | |
13d7a241 | 6526 | * enabled by: attr.comm | attr.mmap | attr.mmap2 | attr.mmap_data | attr.task |
60313ebe PZ |
6527 | */ |
6528 | ||
9f498cc5 | 6529 | struct perf_task_event { |
3a80b4a3 | 6530 | struct task_struct *task; |
cdd6c482 | 6531 | struct perf_event_context *task_ctx; |
60313ebe PZ |
6532 | |
6533 | struct { | |
6534 | struct perf_event_header header; | |
6535 | ||
6536 | u32 pid; | |
6537 | u32 ppid; | |
9f498cc5 PZ |
6538 | u32 tid; |
6539 | u32 ptid; | |
393b2ad8 | 6540 | u64 time; |
cdd6c482 | 6541 | } event_id; |
60313ebe PZ |
6542 | }; |
6543 | ||
67516844 JO |
6544 | static int perf_event_task_match(struct perf_event *event) |
6545 | { | |
13d7a241 SE |
6546 | return event->attr.comm || event->attr.mmap || |
6547 | event->attr.mmap2 || event->attr.mmap_data || | |
6548 | event->attr.task; | |
67516844 JO |
6549 | } |
6550 | ||
cdd6c482 | 6551 | static void perf_event_task_output(struct perf_event *event, |
52d857a8 | 6552 | void *data) |
60313ebe | 6553 | { |
52d857a8 | 6554 | struct perf_task_event *task_event = data; |
60313ebe | 6555 | struct perf_output_handle handle; |
c980d109 | 6556 | struct perf_sample_data sample; |
9f498cc5 | 6557 | struct task_struct *task = task_event->task; |
c980d109 | 6558 | int ret, size = task_event->event_id.header.size; |
8bb39f9a | 6559 | |
67516844 JO |
6560 | if (!perf_event_task_match(event)) |
6561 | return; | |
6562 | ||
c980d109 | 6563 | perf_event_header__init_id(&task_event->event_id.header, &sample, event); |
60313ebe | 6564 | |
c980d109 | 6565 | ret = perf_output_begin(&handle, event, |
a7ac67ea | 6566 | task_event->event_id.header.size); |
ef60777c | 6567 | if (ret) |
c980d109 | 6568 | goto out; |
60313ebe | 6569 | |
cdd6c482 IM |
6570 | task_event->event_id.pid = perf_event_pid(event, task); |
6571 | task_event->event_id.ppid = perf_event_pid(event, current); | |
60313ebe | 6572 | |
cdd6c482 IM |
6573 | task_event->event_id.tid = perf_event_tid(event, task); |
6574 | task_event->event_id.ptid = perf_event_tid(event, current); | |
9f498cc5 | 6575 | |
34f43927 PZ |
6576 | task_event->event_id.time = perf_event_clock(event); |
6577 | ||
cdd6c482 | 6578 | perf_output_put(&handle, task_event->event_id); |
393b2ad8 | 6579 | |
c980d109 ACM |
6580 | perf_event__output_id_sample(event, &handle, &sample); |
6581 | ||
60313ebe | 6582 | perf_output_end(&handle); |
c980d109 ACM |
6583 | out: |
6584 | task_event->event_id.header.size = size; | |
60313ebe PZ |
6585 | } |
6586 | ||
cdd6c482 IM |
6587 | static void perf_event_task(struct task_struct *task, |
6588 | struct perf_event_context *task_ctx, | |
3a80b4a3 | 6589 | int new) |
60313ebe | 6590 | { |
9f498cc5 | 6591 | struct perf_task_event task_event; |
60313ebe | 6592 | |
cdd6c482 IM |
6593 | if (!atomic_read(&nr_comm_events) && |
6594 | !atomic_read(&nr_mmap_events) && | |
6595 | !atomic_read(&nr_task_events)) | |
60313ebe PZ |
6596 | return; |
6597 | ||
9f498cc5 | 6598 | task_event = (struct perf_task_event){ |
3a80b4a3 PZ |
6599 | .task = task, |
6600 | .task_ctx = task_ctx, | |
cdd6c482 | 6601 | .event_id = { |
60313ebe | 6602 | .header = { |
cdd6c482 | 6603 | .type = new ? PERF_RECORD_FORK : PERF_RECORD_EXIT, |
573402db | 6604 | .misc = 0, |
cdd6c482 | 6605 | .size = sizeof(task_event.event_id), |
60313ebe | 6606 | }, |
573402db PZ |
6607 | /* .pid */ |
6608 | /* .ppid */ | |
9f498cc5 PZ |
6609 | /* .tid */ |
6610 | /* .ptid */ | |
34f43927 | 6611 | /* .time */ |
60313ebe PZ |
6612 | }, |
6613 | }; | |
6614 | ||
aab5b71e | 6615 | perf_iterate_sb(perf_event_task_output, |
52d857a8 JO |
6616 | &task_event, |
6617 | task_ctx); | |
9f498cc5 PZ |
6618 | } |
6619 | ||
cdd6c482 | 6620 | void perf_event_fork(struct task_struct *task) |
9f498cc5 | 6621 | { |
cdd6c482 | 6622 | perf_event_task(task, NULL, 1); |
e4222673 | 6623 | perf_event_namespaces(task); |
60313ebe PZ |
6624 | } |
6625 | ||
8d1b2d93 PZ |
6626 | /* |
6627 | * comm tracking | |
6628 | */ | |
6629 | ||
6630 | struct perf_comm_event { | |
22a4f650 IM |
6631 | struct task_struct *task; |
6632 | char *comm; | |
8d1b2d93 PZ |
6633 | int comm_size; |
6634 | ||
6635 | struct { | |
6636 | struct perf_event_header header; | |
6637 | ||
6638 | u32 pid; | |
6639 | u32 tid; | |
cdd6c482 | 6640 | } event_id; |
8d1b2d93 PZ |
6641 | }; |
6642 | ||
67516844 JO |
6643 | static int perf_event_comm_match(struct perf_event *event) |
6644 | { | |
6645 | return event->attr.comm; | |
6646 | } | |
6647 | ||
cdd6c482 | 6648 | static void perf_event_comm_output(struct perf_event *event, |
52d857a8 | 6649 | void *data) |
8d1b2d93 | 6650 | { |
52d857a8 | 6651 | struct perf_comm_event *comm_event = data; |
8d1b2d93 | 6652 | struct perf_output_handle handle; |
c980d109 | 6653 | struct perf_sample_data sample; |
cdd6c482 | 6654 | int size = comm_event->event_id.header.size; |
c980d109 ACM |
6655 | int ret; |
6656 | ||
67516844 JO |
6657 | if (!perf_event_comm_match(event)) |
6658 | return; | |
6659 | ||
c980d109 ACM |
6660 | perf_event_header__init_id(&comm_event->event_id.header, &sample, event); |
6661 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 6662 | comm_event->event_id.header.size); |
8d1b2d93 PZ |
6663 | |
6664 | if (ret) | |
c980d109 | 6665 | goto out; |
8d1b2d93 | 6666 | |
cdd6c482 IM |
6667 | comm_event->event_id.pid = perf_event_pid(event, comm_event->task); |
6668 | comm_event->event_id.tid = perf_event_tid(event, comm_event->task); | |
709e50cf | 6669 | |
cdd6c482 | 6670 | perf_output_put(&handle, comm_event->event_id); |
76369139 | 6671 | __output_copy(&handle, comm_event->comm, |
8d1b2d93 | 6672 | comm_event->comm_size); |
c980d109 ACM |
6673 | |
6674 | perf_event__output_id_sample(event, &handle, &sample); | |
6675 | ||
8d1b2d93 | 6676 | perf_output_end(&handle); |
c980d109 ACM |
6677 | out: |
6678 | comm_event->event_id.header.size = size; | |
8d1b2d93 PZ |
6679 | } |
6680 | ||
cdd6c482 | 6681 | static void perf_event_comm_event(struct perf_comm_event *comm_event) |
8d1b2d93 | 6682 | { |
413ee3b4 | 6683 | char comm[TASK_COMM_LEN]; |
8d1b2d93 | 6684 | unsigned int size; |
8d1b2d93 | 6685 | |
413ee3b4 | 6686 | memset(comm, 0, sizeof(comm)); |
96b02d78 | 6687 | strlcpy(comm, comm_event->task->comm, sizeof(comm)); |
888fcee0 | 6688 | size = ALIGN(strlen(comm)+1, sizeof(u64)); |
8d1b2d93 PZ |
6689 | |
6690 | comm_event->comm = comm; | |
6691 | comm_event->comm_size = size; | |
6692 | ||
cdd6c482 | 6693 | comm_event->event_id.header.size = sizeof(comm_event->event_id) + size; |
8dc85d54 | 6694 | |
aab5b71e | 6695 | perf_iterate_sb(perf_event_comm_output, |
52d857a8 JO |
6696 | comm_event, |
6697 | NULL); | |
8d1b2d93 PZ |
6698 | } |
6699 | ||
82b89778 | 6700 | void perf_event_comm(struct task_struct *task, bool exec) |
8d1b2d93 | 6701 | { |
9ee318a7 PZ |
6702 | struct perf_comm_event comm_event; |
6703 | ||
cdd6c482 | 6704 | if (!atomic_read(&nr_comm_events)) |
9ee318a7 | 6705 | return; |
a63eaf34 | 6706 | |
9ee318a7 | 6707 | comm_event = (struct perf_comm_event){ |
8d1b2d93 | 6708 | .task = task, |
573402db PZ |
6709 | /* .comm */ |
6710 | /* .comm_size */ | |
cdd6c482 | 6711 | .event_id = { |
573402db | 6712 | .header = { |
cdd6c482 | 6713 | .type = PERF_RECORD_COMM, |
82b89778 | 6714 | .misc = exec ? PERF_RECORD_MISC_COMM_EXEC : 0, |
573402db PZ |
6715 | /* .size */ |
6716 | }, | |
6717 | /* .pid */ | |
6718 | /* .tid */ | |
8d1b2d93 PZ |
6719 | }, |
6720 | }; | |
6721 | ||
cdd6c482 | 6722 | perf_event_comm_event(&comm_event); |
8d1b2d93 PZ |
6723 | } |
6724 | ||
e4222673 HB |
6725 | /* |
6726 | * namespaces tracking | |
6727 | */ | |
6728 | ||
6729 | struct perf_namespaces_event { | |
6730 | struct task_struct *task; | |
6731 | ||
6732 | struct { | |
6733 | struct perf_event_header header; | |
6734 | ||
6735 | u32 pid; | |
6736 | u32 tid; | |
6737 | u64 nr_namespaces; | |
6738 | struct perf_ns_link_info link_info[NR_NAMESPACES]; | |
6739 | } event_id; | |
6740 | }; | |
6741 | ||
6742 | static int perf_event_namespaces_match(struct perf_event *event) | |
6743 | { | |
6744 | return event->attr.namespaces; | |
6745 | } | |
6746 | ||
6747 | static void perf_event_namespaces_output(struct perf_event *event, | |
6748 | void *data) | |
6749 | { | |
6750 | struct perf_namespaces_event *namespaces_event = data; | |
6751 | struct perf_output_handle handle; | |
6752 | struct perf_sample_data sample; | |
34900ec5 | 6753 | u16 header_size = namespaces_event->event_id.header.size; |
e4222673 HB |
6754 | int ret; |
6755 | ||
6756 | if (!perf_event_namespaces_match(event)) | |
6757 | return; | |
6758 | ||
6759 | perf_event_header__init_id(&namespaces_event->event_id.header, | |
6760 | &sample, event); | |
6761 | ret = perf_output_begin(&handle, event, | |
6762 | namespaces_event->event_id.header.size); | |
6763 | if (ret) | |
34900ec5 | 6764 | goto out; |
e4222673 HB |
6765 | |
6766 | namespaces_event->event_id.pid = perf_event_pid(event, | |
6767 | namespaces_event->task); | |
6768 | namespaces_event->event_id.tid = perf_event_tid(event, | |
6769 | namespaces_event->task); | |
6770 | ||
6771 | perf_output_put(&handle, namespaces_event->event_id); | |
6772 | ||
6773 | perf_event__output_id_sample(event, &handle, &sample); | |
6774 | ||
6775 | perf_output_end(&handle); | |
34900ec5 JO |
6776 | out: |
6777 | namespaces_event->event_id.header.size = header_size; | |
e4222673 HB |
6778 | } |
6779 | ||
6780 | static void perf_fill_ns_link_info(struct perf_ns_link_info *ns_link_info, | |
6781 | struct task_struct *task, | |
6782 | const struct proc_ns_operations *ns_ops) | |
6783 | { | |
6784 | struct path ns_path; | |
6785 | struct inode *ns_inode; | |
6786 | void *error; | |
6787 | ||
6788 | error = ns_get_path(&ns_path, task, ns_ops); | |
6789 | if (!error) { | |
6790 | ns_inode = ns_path.dentry->d_inode; | |
6791 | ns_link_info->dev = new_encode_dev(ns_inode->i_sb->s_dev); | |
6792 | ns_link_info->ino = ns_inode->i_ino; | |
0e18dd12 | 6793 | path_put(&ns_path); |
e4222673 HB |
6794 | } |
6795 | } | |
6796 | ||
6797 | void perf_event_namespaces(struct task_struct *task) | |
6798 | { | |
6799 | struct perf_namespaces_event namespaces_event; | |
6800 | struct perf_ns_link_info *ns_link_info; | |
6801 | ||
6802 | if (!atomic_read(&nr_namespaces_events)) | |
6803 | return; | |
6804 | ||
6805 | namespaces_event = (struct perf_namespaces_event){ | |
6806 | .task = task, | |
6807 | .event_id = { | |
6808 | .header = { | |
6809 | .type = PERF_RECORD_NAMESPACES, | |
6810 | .misc = 0, | |
6811 | .size = sizeof(namespaces_event.event_id), | |
6812 | }, | |
6813 | /* .pid */ | |
6814 | /* .tid */ | |
6815 | .nr_namespaces = NR_NAMESPACES, | |
6816 | /* .link_info[NR_NAMESPACES] */ | |
6817 | }, | |
6818 | }; | |
6819 | ||
6820 | ns_link_info = namespaces_event.event_id.link_info; | |
6821 | ||
6822 | perf_fill_ns_link_info(&ns_link_info[MNT_NS_INDEX], | |
6823 | task, &mntns_operations); | |
6824 | ||
6825 | #ifdef CONFIG_USER_NS | |
6826 | perf_fill_ns_link_info(&ns_link_info[USER_NS_INDEX], | |
6827 | task, &userns_operations); | |
6828 | #endif | |
6829 | #ifdef CONFIG_NET_NS | |
6830 | perf_fill_ns_link_info(&ns_link_info[NET_NS_INDEX], | |
6831 | task, &netns_operations); | |
6832 | #endif | |
6833 | #ifdef CONFIG_UTS_NS | |
6834 | perf_fill_ns_link_info(&ns_link_info[UTS_NS_INDEX], | |
6835 | task, &utsns_operations); | |
6836 | #endif | |
6837 | #ifdef CONFIG_IPC_NS | |
6838 | perf_fill_ns_link_info(&ns_link_info[IPC_NS_INDEX], | |
6839 | task, &ipcns_operations); | |
6840 | #endif | |
6841 | #ifdef CONFIG_PID_NS | |
6842 | perf_fill_ns_link_info(&ns_link_info[PID_NS_INDEX], | |
6843 | task, &pidns_operations); | |
6844 | #endif | |
6845 | #ifdef CONFIG_CGROUPS | |
6846 | perf_fill_ns_link_info(&ns_link_info[CGROUP_NS_INDEX], | |
6847 | task, &cgroupns_operations); | |
6848 | #endif | |
6849 | ||
6850 | perf_iterate_sb(perf_event_namespaces_output, | |
6851 | &namespaces_event, | |
6852 | NULL); | |
6853 | } | |
6854 | ||
0a4a9391 PZ |
6855 | /* |
6856 | * mmap tracking | |
6857 | */ | |
6858 | ||
6859 | struct perf_mmap_event { | |
089dd79d PZ |
6860 | struct vm_area_struct *vma; |
6861 | ||
6862 | const char *file_name; | |
6863 | int file_size; | |
13d7a241 SE |
6864 | int maj, min; |
6865 | u64 ino; | |
6866 | u64 ino_generation; | |
f972eb63 | 6867 | u32 prot, flags; |
0a4a9391 PZ |
6868 | |
6869 | struct { | |
6870 | struct perf_event_header header; | |
6871 | ||
6872 | u32 pid; | |
6873 | u32 tid; | |
6874 | u64 start; | |
6875 | u64 len; | |
6876 | u64 pgoff; | |
cdd6c482 | 6877 | } event_id; |
0a4a9391 PZ |
6878 | }; |
6879 | ||
67516844 JO |
6880 | static int perf_event_mmap_match(struct perf_event *event, |
6881 | void *data) | |
6882 | { | |
6883 | struct perf_mmap_event *mmap_event = data; | |
6884 | struct vm_area_struct *vma = mmap_event->vma; | |
6885 | int executable = vma->vm_flags & VM_EXEC; | |
6886 | ||
6887 | return (!executable && event->attr.mmap_data) || | |
13d7a241 | 6888 | (executable && (event->attr.mmap || event->attr.mmap2)); |
67516844 JO |
6889 | } |
6890 | ||
cdd6c482 | 6891 | static void perf_event_mmap_output(struct perf_event *event, |
52d857a8 | 6892 | void *data) |
0a4a9391 | 6893 | { |
52d857a8 | 6894 | struct perf_mmap_event *mmap_event = data; |
0a4a9391 | 6895 | struct perf_output_handle handle; |
c980d109 | 6896 | struct perf_sample_data sample; |
cdd6c482 | 6897 | int size = mmap_event->event_id.header.size; |
87a8ec33 | 6898 | u32 type = mmap_event->event_id.header.type; |
c980d109 | 6899 | int ret; |
0a4a9391 | 6900 | |
67516844 JO |
6901 | if (!perf_event_mmap_match(event, data)) |
6902 | return; | |
6903 | ||
13d7a241 SE |
6904 | if (event->attr.mmap2) { |
6905 | mmap_event->event_id.header.type = PERF_RECORD_MMAP2; | |
6906 | mmap_event->event_id.header.size += sizeof(mmap_event->maj); | |
6907 | mmap_event->event_id.header.size += sizeof(mmap_event->min); | |
6908 | mmap_event->event_id.header.size += sizeof(mmap_event->ino); | |
d008d525 | 6909 | mmap_event->event_id.header.size += sizeof(mmap_event->ino_generation); |
f972eb63 PZ |
6910 | mmap_event->event_id.header.size += sizeof(mmap_event->prot); |
6911 | mmap_event->event_id.header.size += sizeof(mmap_event->flags); | |
13d7a241 SE |
6912 | } |
6913 | ||
c980d109 ACM |
6914 | perf_event_header__init_id(&mmap_event->event_id.header, &sample, event); |
6915 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 6916 | mmap_event->event_id.header.size); |
0a4a9391 | 6917 | if (ret) |
c980d109 | 6918 | goto out; |
0a4a9391 | 6919 | |
cdd6c482 IM |
6920 | mmap_event->event_id.pid = perf_event_pid(event, current); |
6921 | mmap_event->event_id.tid = perf_event_tid(event, current); | |
709e50cf | 6922 | |
cdd6c482 | 6923 | perf_output_put(&handle, mmap_event->event_id); |
13d7a241 SE |
6924 | |
6925 | if (event->attr.mmap2) { | |
6926 | perf_output_put(&handle, mmap_event->maj); | |
6927 | perf_output_put(&handle, mmap_event->min); | |
6928 | perf_output_put(&handle, mmap_event->ino); | |
6929 | perf_output_put(&handle, mmap_event->ino_generation); | |
f972eb63 PZ |
6930 | perf_output_put(&handle, mmap_event->prot); |
6931 | perf_output_put(&handle, mmap_event->flags); | |
13d7a241 SE |
6932 | } |
6933 | ||
76369139 | 6934 | __output_copy(&handle, mmap_event->file_name, |
0a4a9391 | 6935 | mmap_event->file_size); |
c980d109 ACM |
6936 | |
6937 | perf_event__output_id_sample(event, &handle, &sample); | |
6938 | ||
78d613eb | 6939 | perf_output_end(&handle); |
c980d109 ACM |
6940 | out: |
6941 | mmap_event->event_id.header.size = size; | |
87a8ec33 | 6942 | mmap_event->event_id.header.type = type; |
0a4a9391 PZ |
6943 | } |
6944 | ||
cdd6c482 | 6945 | static void perf_event_mmap_event(struct perf_mmap_event *mmap_event) |
0a4a9391 | 6946 | { |
089dd79d PZ |
6947 | struct vm_area_struct *vma = mmap_event->vma; |
6948 | struct file *file = vma->vm_file; | |
13d7a241 SE |
6949 | int maj = 0, min = 0; |
6950 | u64 ino = 0, gen = 0; | |
f972eb63 | 6951 | u32 prot = 0, flags = 0; |
0a4a9391 PZ |
6952 | unsigned int size; |
6953 | char tmp[16]; | |
6954 | char *buf = NULL; | |
2c42cfbf | 6955 | char *name; |
413ee3b4 | 6956 | |
0b3589be PZ |
6957 | if (vma->vm_flags & VM_READ) |
6958 | prot |= PROT_READ; | |
6959 | if (vma->vm_flags & VM_WRITE) | |
6960 | prot |= PROT_WRITE; | |
6961 | if (vma->vm_flags & VM_EXEC) | |
6962 | prot |= PROT_EXEC; | |
6963 | ||
6964 | if (vma->vm_flags & VM_MAYSHARE) | |
6965 | flags = MAP_SHARED; | |
6966 | else | |
6967 | flags = MAP_PRIVATE; | |
6968 | ||
6969 | if (vma->vm_flags & VM_DENYWRITE) | |
6970 | flags |= MAP_DENYWRITE; | |
6971 | if (vma->vm_flags & VM_MAYEXEC) | |
6972 | flags |= MAP_EXECUTABLE; | |
6973 | if (vma->vm_flags & VM_LOCKED) | |
6974 | flags |= MAP_LOCKED; | |
6975 | if (vma->vm_flags & VM_HUGETLB) | |
6976 | flags |= MAP_HUGETLB; | |
6977 | ||
0a4a9391 | 6978 | if (file) { |
13d7a241 SE |
6979 | struct inode *inode; |
6980 | dev_t dev; | |
3ea2f2b9 | 6981 | |
2c42cfbf | 6982 | buf = kmalloc(PATH_MAX, GFP_KERNEL); |
0a4a9391 | 6983 | if (!buf) { |
c7e548b4 ON |
6984 | name = "//enomem"; |
6985 | goto cpy_name; | |
0a4a9391 | 6986 | } |
413ee3b4 | 6987 | /* |
3ea2f2b9 | 6988 | * d_path() works from the end of the rb backwards, so we |
413ee3b4 AB |
6989 | * need to add enough zero bytes after the string to handle |
6990 | * the 64bit alignment we do later. | |
6991 | */ | |
9bf39ab2 | 6992 | name = file_path(file, buf, PATH_MAX - sizeof(u64)); |
0a4a9391 | 6993 | if (IS_ERR(name)) { |
c7e548b4 ON |
6994 | name = "//toolong"; |
6995 | goto cpy_name; | |
0a4a9391 | 6996 | } |
13d7a241 SE |
6997 | inode = file_inode(vma->vm_file); |
6998 | dev = inode->i_sb->s_dev; | |
6999 | ino = inode->i_ino; | |
7000 | gen = inode->i_generation; | |
7001 | maj = MAJOR(dev); | |
7002 | min = MINOR(dev); | |
f972eb63 | 7003 | |
c7e548b4 | 7004 | goto got_name; |
0a4a9391 | 7005 | } else { |
fbe26abe JO |
7006 | if (vma->vm_ops && vma->vm_ops->name) { |
7007 | name = (char *) vma->vm_ops->name(vma); | |
7008 | if (name) | |
7009 | goto cpy_name; | |
7010 | } | |
7011 | ||
2c42cfbf | 7012 | name = (char *)arch_vma_name(vma); |
c7e548b4 ON |
7013 | if (name) |
7014 | goto cpy_name; | |
089dd79d | 7015 | |
32c5fb7e | 7016 | if (vma->vm_start <= vma->vm_mm->start_brk && |
3af9e859 | 7017 | vma->vm_end >= vma->vm_mm->brk) { |
c7e548b4 ON |
7018 | name = "[heap]"; |
7019 | goto cpy_name; | |
32c5fb7e ON |
7020 | } |
7021 | if (vma->vm_start <= vma->vm_mm->start_stack && | |
3af9e859 | 7022 | vma->vm_end >= vma->vm_mm->start_stack) { |
c7e548b4 ON |
7023 | name = "[stack]"; |
7024 | goto cpy_name; | |
089dd79d PZ |
7025 | } |
7026 | ||
c7e548b4 ON |
7027 | name = "//anon"; |
7028 | goto cpy_name; | |
0a4a9391 PZ |
7029 | } |
7030 | ||
c7e548b4 ON |
7031 | cpy_name: |
7032 | strlcpy(tmp, name, sizeof(tmp)); | |
7033 | name = tmp; | |
0a4a9391 | 7034 | got_name: |
2c42cfbf PZ |
7035 | /* |
7036 | * Since our buffer works in 8 byte units we need to align our string | |
7037 | * size to a multiple of 8. However, we must guarantee the tail end is | |
7038 | * zero'd out to avoid leaking random bits to userspace. | |
7039 | */ | |
7040 | size = strlen(name)+1; | |
7041 | while (!IS_ALIGNED(size, sizeof(u64))) | |
7042 | name[size++] = '\0'; | |
0a4a9391 PZ |
7043 | |
7044 | mmap_event->file_name = name; | |
7045 | mmap_event->file_size = size; | |
13d7a241 SE |
7046 | mmap_event->maj = maj; |
7047 | mmap_event->min = min; | |
7048 | mmap_event->ino = ino; | |
7049 | mmap_event->ino_generation = gen; | |
f972eb63 PZ |
7050 | mmap_event->prot = prot; |
7051 | mmap_event->flags = flags; | |
0a4a9391 | 7052 | |
2fe85427 SE |
7053 | if (!(vma->vm_flags & VM_EXEC)) |
7054 | mmap_event->event_id.header.misc |= PERF_RECORD_MISC_MMAP_DATA; | |
7055 | ||
cdd6c482 | 7056 | mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size; |
0a4a9391 | 7057 | |
aab5b71e | 7058 | perf_iterate_sb(perf_event_mmap_output, |
52d857a8 JO |
7059 | mmap_event, |
7060 | NULL); | |
665c2142 | 7061 | |
0a4a9391 PZ |
7062 | kfree(buf); |
7063 | } | |
7064 | ||
375637bc AS |
7065 | /* |
7066 | * Check whether inode and address range match filter criteria. | |
7067 | */ | |
7068 | static bool perf_addr_filter_match(struct perf_addr_filter *filter, | |
7069 | struct file *file, unsigned long offset, | |
7070 | unsigned long size) | |
7071 | { | |
45063097 | 7072 | if (filter->inode != file_inode(file)) |
375637bc AS |
7073 | return false; |
7074 | ||
7075 | if (filter->offset > offset + size) | |
7076 | return false; | |
7077 | ||
7078 | if (filter->offset + filter->size < offset) | |
7079 | return false; | |
7080 | ||
7081 | return true; | |
7082 | } | |
7083 | ||
7084 | static void __perf_addr_filters_adjust(struct perf_event *event, void *data) | |
7085 | { | |
7086 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
7087 | struct vm_area_struct *vma = data; | |
7088 | unsigned long off = vma->vm_pgoff << PAGE_SHIFT, flags; | |
7089 | struct file *file = vma->vm_file; | |
7090 | struct perf_addr_filter *filter; | |
7091 | unsigned int restart = 0, count = 0; | |
7092 | ||
7093 | if (!has_addr_filter(event)) | |
7094 | return; | |
7095 | ||
7096 | if (!file) | |
7097 | return; | |
7098 | ||
7099 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
7100 | list_for_each_entry(filter, &ifh->list, entry) { | |
7101 | if (perf_addr_filter_match(filter, file, off, | |
7102 | vma->vm_end - vma->vm_start)) { | |
7103 | event->addr_filters_offs[count] = vma->vm_start; | |
7104 | restart++; | |
7105 | } | |
7106 | ||
7107 | count++; | |
7108 | } | |
7109 | ||
7110 | if (restart) | |
7111 | event->addr_filters_gen++; | |
7112 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
7113 | ||
7114 | if (restart) | |
767ae086 | 7115 | perf_event_stop(event, 1); |
375637bc AS |
7116 | } |
7117 | ||
7118 | /* | |
7119 | * Adjust all task's events' filters to the new vma | |
7120 | */ | |
7121 | static void perf_addr_filters_adjust(struct vm_area_struct *vma) | |
7122 | { | |
7123 | struct perf_event_context *ctx; | |
7124 | int ctxn; | |
7125 | ||
12b40a23 MP |
7126 | /* |
7127 | * Data tracing isn't supported yet and as such there is no need | |
7128 | * to keep track of anything that isn't related to executable code: | |
7129 | */ | |
7130 | if (!(vma->vm_flags & VM_EXEC)) | |
7131 | return; | |
7132 | ||
375637bc AS |
7133 | rcu_read_lock(); |
7134 | for_each_task_context_nr(ctxn) { | |
7135 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); | |
7136 | if (!ctx) | |
7137 | continue; | |
7138 | ||
aab5b71e | 7139 | perf_iterate_ctx(ctx, __perf_addr_filters_adjust, vma, true); |
375637bc AS |
7140 | } |
7141 | rcu_read_unlock(); | |
7142 | } | |
7143 | ||
3af9e859 | 7144 | void perf_event_mmap(struct vm_area_struct *vma) |
0a4a9391 | 7145 | { |
9ee318a7 PZ |
7146 | struct perf_mmap_event mmap_event; |
7147 | ||
cdd6c482 | 7148 | if (!atomic_read(&nr_mmap_events)) |
9ee318a7 PZ |
7149 | return; |
7150 | ||
7151 | mmap_event = (struct perf_mmap_event){ | |
089dd79d | 7152 | .vma = vma, |
573402db PZ |
7153 | /* .file_name */ |
7154 | /* .file_size */ | |
cdd6c482 | 7155 | .event_id = { |
573402db | 7156 | .header = { |
cdd6c482 | 7157 | .type = PERF_RECORD_MMAP, |
39447b38 | 7158 | .misc = PERF_RECORD_MISC_USER, |
573402db PZ |
7159 | /* .size */ |
7160 | }, | |
7161 | /* .pid */ | |
7162 | /* .tid */ | |
089dd79d PZ |
7163 | .start = vma->vm_start, |
7164 | .len = vma->vm_end - vma->vm_start, | |
3a0304e9 | 7165 | .pgoff = (u64)vma->vm_pgoff << PAGE_SHIFT, |
0a4a9391 | 7166 | }, |
13d7a241 SE |
7167 | /* .maj (attr_mmap2 only) */ |
7168 | /* .min (attr_mmap2 only) */ | |
7169 | /* .ino (attr_mmap2 only) */ | |
7170 | /* .ino_generation (attr_mmap2 only) */ | |
f972eb63 PZ |
7171 | /* .prot (attr_mmap2 only) */ |
7172 | /* .flags (attr_mmap2 only) */ | |
0a4a9391 PZ |
7173 | }; |
7174 | ||
375637bc | 7175 | perf_addr_filters_adjust(vma); |
cdd6c482 | 7176 | perf_event_mmap_event(&mmap_event); |
0a4a9391 PZ |
7177 | } |
7178 | ||
68db7e98 AS |
7179 | void perf_event_aux_event(struct perf_event *event, unsigned long head, |
7180 | unsigned long size, u64 flags) | |
7181 | { | |
7182 | struct perf_output_handle handle; | |
7183 | struct perf_sample_data sample; | |
7184 | struct perf_aux_event { | |
7185 | struct perf_event_header header; | |
7186 | u64 offset; | |
7187 | u64 size; | |
7188 | u64 flags; | |
7189 | } rec = { | |
7190 | .header = { | |
7191 | .type = PERF_RECORD_AUX, | |
7192 | .misc = 0, | |
7193 | .size = sizeof(rec), | |
7194 | }, | |
7195 | .offset = head, | |
7196 | .size = size, | |
7197 | .flags = flags, | |
7198 | }; | |
7199 | int ret; | |
7200 | ||
7201 | perf_event_header__init_id(&rec.header, &sample, event); | |
7202 | ret = perf_output_begin(&handle, event, rec.header.size); | |
7203 | ||
7204 | if (ret) | |
7205 | return; | |
7206 | ||
7207 | perf_output_put(&handle, rec); | |
7208 | perf_event__output_id_sample(event, &handle, &sample); | |
7209 | ||
7210 | perf_output_end(&handle); | |
7211 | } | |
7212 | ||
f38b0dbb KL |
7213 | /* |
7214 | * Lost/dropped samples logging | |
7215 | */ | |
7216 | void perf_log_lost_samples(struct perf_event *event, u64 lost) | |
7217 | { | |
7218 | struct perf_output_handle handle; | |
7219 | struct perf_sample_data sample; | |
7220 | int ret; | |
7221 | ||
7222 | struct { | |
7223 | struct perf_event_header header; | |
7224 | u64 lost; | |
7225 | } lost_samples_event = { | |
7226 | .header = { | |
7227 | .type = PERF_RECORD_LOST_SAMPLES, | |
7228 | .misc = 0, | |
7229 | .size = sizeof(lost_samples_event), | |
7230 | }, | |
7231 | .lost = lost, | |
7232 | }; | |
7233 | ||
7234 | perf_event_header__init_id(&lost_samples_event.header, &sample, event); | |
7235 | ||
7236 | ret = perf_output_begin(&handle, event, | |
7237 | lost_samples_event.header.size); | |
7238 | if (ret) | |
7239 | return; | |
7240 | ||
7241 | perf_output_put(&handle, lost_samples_event); | |
7242 | perf_event__output_id_sample(event, &handle, &sample); | |
7243 | perf_output_end(&handle); | |
7244 | } | |
7245 | ||
45ac1403 AH |
7246 | /* |
7247 | * context_switch tracking | |
7248 | */ | |
7249 | ||
7250 | struct perf_switch_event { | |
7251 | struct task_struct *task; | |
7252 | struct task_struct *next_prev; | |
7253 | ||
7254 | struct { | |
7255 | struct perf_event_header header; | |
7256 | u32 next_prev_pid; | |
7257 | u32 next_prev_tid; | |
7258 | } event_id; | |
7259 | }; | |
7260 | ||
7261 | static int perf_event_switch_match(struct perf_event *event) | |
7262 | { | |
7263 | return event->attr.context_switch; | |
7264 | } | |
7265 | ||
7266 | static void perf_event_switch_output(struct perf_event *event, void *data) | |
7267 | { | |
7268 | struct perf_switch_event *se = data; | |
7269 | struct perf_output_handle handle; | |
7270 | struct perf_sample_data sample; | |
7271 | int ret; | |
7272 | ||
7273 | if (!perf_event_switch_match(event)) | |
7274 | return; | |
7275 | ||
7276 | /* Only CPU-wide events are allowed to see next/prev pid/tid */ | |
7277 | if (event->ctx->task) { | |
7278 | se->event_id.header.type = PERF_RECORD_SWITCH; | |
7279 | se->event_id.header.size = sizeof(se->event_id.header); | |
7280 | } else { | |
7281 | se->event_id.header.type = PERF_RECORD_SWITCH_CPU_WIDE; | |
7282 | se->event_id.header.size = sizeof(se->event_id); | |
7283 | se->event_id.next_prev_pid = | |
7284 | perf_event_pid(event, se->next_prev); | |
7285 | se->event_id.next_prev_tid = | |
7286 | perf_event_tid(event, se->next_prev); | |
7287 | } | |
7288 | ||
7289 | perf_event_header__init_id(&se->event_id.header, &sample, event); | |
7290 | ||
7291 | ret = perf_output_begin(&handle, event, se->event_id.header.size); | |
7292 | if (ret) | |
7293 | return; | |
7294 | ||
7295 | if (event->ctx->task) | |
7296 | perf_output_put(&handle, se->event_id.header); | |
7297 | else | |
7298 | perf_output_put(&handle, se->event_id); | |
7299 | ||
7300 | perf_event__output_id_sample(event, &handle, &sample); | |
7301 | ||
7302 | perf_output_end(&handle); | |
7303 | } | |
7304 | ||
7305 | static void perf_event_switch(struct task_struct *task, | |
7306 | struct task_struct *next_prev, bool sched_in) | |
7307 | { | |
7308 | struct perf_switch_event switch_event; | |
7309 | ||
7310 | /* N.B. caller checks nr_switch_events != 0 */ | |
7311 | ||
7312 | switch_event = (struct perf_switch_event){ | |
7313 | .task = task, | |
7314 | .next_prev = next_prev, | |
7315 | .event_id = { | |
7316 | .header = { | |
7317 | /* .type */ | |
7318 | .misc = sched_in ? 0 : PERF_RECORD_MISC_SWITCH_OUT, | |
7319 | /* .size */ | |
7320 | }, | |
7321 | /* .next_prev_pid */ | |
7322 | /* .next_prev_tid */ | |
7323 | }, | |
7324 | }; | |
7325 | ||
aab5b71e | 7326 | perf_iterate_sb(perf_event_switch_output, |
45ac1403 AH |
7327 | &switch_event, |
7328 | NULL); | |
7329 | } | |
7330 | ||
a78ac325 PZ |
7331 | /* |
7332 | * IRQ throttle logging | |
7333 | */ | |
7334 | ||
cdd6c482 | 7335 | static void perf_log_throttle(struct perf_event *event, int enable) |
a78ac325 PZ |
7336 | { |
7337 | struct perf_output_handle handle; | |
c980d109 | 7338 | struct perf_sample_data sample; |
a78ac325 PZ |
7339 | int ret; |
7340 | ||
7341 | struct { | |
7342 | struct perf_event_header header; | |
7343 | u64 time; | |
cca3f454 | 7344 | u64 id; |
7f453c24 | 7345 | u64 stream_id; |
a78ac325 PZ |
7346 | } throttle_event = { |
7347 | .header = { | |
cdd6c482 | 7348 | .type = PERF_RECORD_THROTTLE, |
a78ac325 PZ |
7349 | .misc = 0, |
7350 | .size = sizeof(throttle_event), | |
7351 | }, | |
34f43927 | 7352 | .time = perf_event_clock(event), |
cdd6c482 IM |
7353 | .id = primary_event_id(event), |
7354 | .stream_id = event->id, | |
a78ac325 PZ |
7355 | }; |
7356 | ||
966ee4d6 | 7357 | if (enable) |
cdd6c482 | 7358 | throttle_event.header.type = PERF_RECORD_UNTHROTTLE; |
966ee4d6 | 7359 | |
c980d109 ACM |
7360 | perf_event_header__init_id(&throttle_event.header, &sample, event); |
7361 | ||
7362 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 7363 | throttle_event.header.size); |
a78ac325 PZ |
7364 | if (ret) |
7365 | return; | |
7366 | ||
7367 | perf_output_put(&handle, throttle_event); | |
c980d109 | 7368 | perf_event__output_id_sample(event, &handle, &sample); |
a78ac325 PZ |
7369 | perf_output_end(&handle); |
7370 | } | |
7371 | ||
8d4e6c4c AS |
7372 | void perf_event_itrace_started(struct perf_event *event) |
7373 | { | |
7374 | event->attach_state |= PERF_ATTACH_ITRACE; | |
7375 | } | |
7376 | ||
ec0d7729 AS |
7377 | static void perf_log_itrace_start(struct perf_event *event) |
7378 | { | |
7379 | struct perf_output_handle handle; | |
7380 | struct perf_sample_data sample; | |
7381 | struct perf_aux_event { | |
7382 | struct perf_event_header header; | |
7383 | u32 pid; | |
7384 | u32 tid; | |
7385 | } rec; | |
7386 | int ret; | |
7387 | ||
7388 | if (event->parent) | |
7389 | event = event->parent; | |
7390 | ||
7391 | if (!(event->pmu->capabilities & PERF_PMU_CAP_ITRACE) || | |
8d4e6c4c | 7392 | event->attach_state & PERF_ATTACH_ITRACE) |
ec0d7729 AS |
7393 | return; |
7394 | ||
ec0d7729 AS |
7395 | rec.header.type = PERF_RECORD_ITRACE_START; |
7396 | rec.header.misc = 0; | |
7397 | rec.header.size = sizeof(rec); | |
7398 | rec.pid = perf_event_pid(event, current); | |
7399 | rec.tid = perf_event_tid(event, current); | |
7400 | ||
7401 | perf_event_header__init_id(&rec.header, &sample, event); | |
7402 | ret = perf_output_begin(&handle, event, rec.header.size); | |
7403 | ||
7404 | if (ret) | |
7405 | return; | |
7406 | ||
7407 | perf_output_put(&handle, rec); | |
7408 | perf_event__output_id_sample(event, &handle, &sample); | |
7409 | ||
7410 | perf_output_end(&handle); | |
7411 | } | |
7412 | ||
475113d9 JO |
7413 | static int |
7414 | __perf_event_account_interrupt(struct perf_event *event, int throttle) | |
f6c7d5fe | 7415 | { |
cdd6c482 | 7416 | struct hw_perf_event *hwc = &event->hw; |
79f14641 | 7417 | int ret = 0; |
475113d9 | 7418 | u64 seq; |
96398826 | 7419 | |
e050e3f0 SE |
7420 | seq = __this_cpu_read(perf_throttled_seq); |
7421 | if (seq != hwc->interrupts_seq) { | |
7422 | hwc->interrupts_seq = seq; | |
7423 | hwc->interrupts = 1; | |
7424 | } else { | |
7425 | hwc->interrupts++; | |
7426 | if (unlikely(throttle | |
7427 | && hwc->interrupts >= max_samples_per_tick)) { | |
7428 | __this_cpu_inc(perf_throttled_count); | |
555e0c1e | 7429 | tick_dep_set_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
163ec435 PZ |
7430 | hwc->interrupts = MAX_INTERRUPTS; |
7431 | perf_log_throttle(event, 0); | |
a78ac325 PZ |
7432 | ret = 1; |
7433 | } | |
e050e3f0 | 7434 | } |
60db5e09 | 7435 | |
cdd6c482 | 7436 | if (event->attr.freq) { |
def0a9b2 | 7437 | u64 now = perf_clock(); |
abd50713 | 7438 | s64 delta = now - hwc->freq_time_stamp; |
bd2b5b12 | 7439 | |
abd50713 | 7440 | hwc->freq_time_stamp = now; |
bd2b5b12 | 7441 | |
abd50713 | 7442 | if (delta > 0 && delta < 2*TICK_NSEC) |
f39d47ff | 7443 | perf_adjust_period(event, delta, hwc->last_period, true); |
bd2b5b12 PZ |
7444 | } |
7445 | ||
475113d9 JO |
7446 | return ret; |
7447 | } | |
7448 | ||
7449 | int perf_event_account_interrupt(struct perf_event *event) | |
7450 | { | |
7451 | return __perf_event_account_interrupt(event, 1); | |
7452 | } | |
7453 | ||
7454 | /* | |
7455 | * Generic event overflow handling, sampling. | |
7456 | */ | |
7457 | ||
7458 | static int __perf_event_overflow(struct perf_event *event, | |
7459 | int throttle, struct perf_sample_data *data, | |
7460 | struct pt_regs *regs) | |
7461 | { | |
7462 | int events = atomic_read(&event->event_limit); | |
7463 | int ret = 0; | |
7464 | ||
7465 | /* | |
7466 | * Non-sampling counters might still use the PMI to fold short | |
7467 | * hardware counters, ignore those. | |
7468 | */ | |
7469 | if (unlikely(!is_sampling_event(event))) | |
7470 | return 0; | |
7471 | ||
7472 | ret = __perf_event_account_interrupt(event, throttle); | |
cc1582c2 | 7473 | |
2023b359 PZ |
7474 | /* |
7475 | * XXX event_limit might not quite work as expected on inherited | |
cdd6c482 | 7476 | * events |
2023b359 PZ |
7477 | */ |
7478 | ||
cdd6c482 IM |
7479 | event->pending_kill = POLL_IN; |
7480 | if (events && atomic_dec_and_test(&event->event_limit)) { | |
79f14641 | 7481 | ret = 1; |
cdd6c482 | 7482 | event->pending_kill = POLL_HUP; |
5aab90ce JO |
7483 | |
7484 | perf_event_disable_inatomic(event); | |
79f14641 PZ |
7485 | } |
7486 | ||
aa6a5f3c | 7487 | READ_ONCE(event->overflow_handler)(event, data, regs); |
453f19ee | 7488 | |
fed66e2c | 7489 | if (*perf_event_fasync(event) && event->pending_kill) { |
a8b0ca17 PZ |
7490 | event->pending_wakeup = 1; |
7491 | irq_work_queue(&event->pending); | |
f506b3dc PZ |
7492 | } |
7493 | ||
79f14641 | 7494 | return ret; |
f6c7d5fe PZ |
7495 | } |
7496 | ||
a8b0ca17 | 7497 | int perf_event_overflow(struct perf_event *event, |
5622f295 MM |
7498 | struct perf_sample_data *data, |
7499 | struct pt_regs *regs) | |
850bc73f | 7500 | { |
a8b0ca17 | 7501 | return __perf_event_overflow(event, 1, data, regs); |
850bc73f PZ |
7502 | } |
7503 | ||
15dbf27c | 7504 | /* |
cdd6c482 | 7505 | * Generic software event infrastructure |
15dbf27c PZ |
7506 | */ |
7507 | ||
b28ab83c PZ |
7508 | struct swevent_htable { |
7509 | struct swevent_hlist *swevent_hlist; | |
7510 | struct mutex hlist_mutex; | |
7511 | int hlist_refcount; | |
7512 | ||
7513 | /* Recursion avoidance in each contexts */ | |
7514 | int recursion[PERF_NR_CONTEXTS]; | |
7515 | }; | |
7516 | ||
7517 | static DEFINE_PER_CPU(struct swevent_htable, swevent_htable); | |
7518 | ||
7b4b6658 | 7519 | /* |
cdd6c482 IM |
7520 | * We directly increment event->count and keep a second value in |
7521 | * event->hw.period_left to count intervals. This period event | |
7b4b6658 PZ |
7522 | * is kept in the range [-sample_period, 0] so that we can use the |
7523 | * sign as trigger. | |
7524 | */ | |
7525 | ||
ab573844 | 7526 | u64 perf_swevent_set_period(struct perf_event *event) |
15dbf27c | 7527 | { |
cdd6c482 | 7528 | struct hw_perf_event *hwc = &event->hw; |
7b4b6658 PZ |
7529 | u64 period = hwc->last_period; |
7530 | u64 nr, offset; | |
7531 | s64 old, val; | |
7532 | ||
7533 | hwc->last_period = hwc->sample_period; | |
15dbf27c PZ |
7534 | |
7535 | again: | |
e7850595 | 7536 | old = val = local64_read(&hwc->period_left); |
7b4b6658 PZ |
7537 | if (val < 0) |
7538 | return 0; | |
15dbf27c | 7539 | |
7b4b6658 PZ |
7540 | nr = div64_u64(period + val, period); |
7541 | offset = nr * period; | |
7542 | val -= offset; | |
e7850595 | 7543 | if (local64_cmpxchg(&hwc->period_left, old, val) != old) |
7b4b6658 | 7544 | goto again; |
15dbf27c | 7545 | |
7b4b6658 | 7546 | return nr; |
15dbf27c PZ |
7547 | } |
7548 | ||
0cff784a | 7549 | static void perf_swevent_overflow(struct perf_event *event, u64 overflow, |
a8b0ca17 | 7550 | struct perf_sample_data *data, |
5622f295 | 7551 | struct pt_regs *regs) |
15dbf27c | 7552 | { |
cdd6c482 | 7553 | struct hw_perf_event *hwc = &event->hw; |
850bc73f | 7554 | int throttle = 0; |
15dbf27c | 7555 | |
0cff784a PZ |
7556 | if (!overflow) |
7557 | overflow = perf_swevent_set_period(event); | |
15dbf27c | 7558 | |
7b4b6658 PZ |
7559 | if (hwc->interrupts == MAX_INTERRUPTS) |
7560 | return; | |
15dbf27c | 7561 | |
7b4b6658 | 7562 | for (; overflow; overflow--) { |
a8b0ca17 | 7563 | if (__perf_event_overflow(event, throttle, |
5622f295 | 7564 | data, regs)) { |
7b4b6658 PZ |
7565 | /* |
7566 | * We inhibit the overflow from happening when | |
7567 | * hwc->interrupts == MAX_INTERRUPTS. | |
7568 | */ | |
7569 | break; | |
7570 | } | |
cf450a73 | 7571 | throttle = 1; |
7b4b6658 | 7572 | } |
15dbf27c PZ |
7573 | } |
7574 | ||
a4eaf7f1 | 7575 | static void perf_swevent_event(struct perf_event *event, u64 nr, |
a8b0ca17 | 7576 | struct perf_sample_data *data, |
5622f295 | 7577 | struct pt_regs *regs) |
7b4b6658 | 7578 | { |
cdd6c482 | 7579 | struct hw_perf_event *hwc = &event->hw; |
d6d020e9 | 7580 | |
e7850595 | 7581 | local64_add(nr, &event->count); |
d6d020e9 | 7582 | |
0cff784a PZ |
7583 | if (!regs) |
7584 | return; | |
7585 | ||
6c7e550f | 7586 | if (!is_sampling_event(event)) |
7b4b6658 | 7587 | return; |
d6d020e9 | 7588 | |
5d81e5cf AV |
7589 | if ((event->attr.sample_type & PERF_SAMPLE_PERIOD) && !event->attr.freq) { |
7590 | data->period = nr; | |
7591 | return perf_swevent_overflow(event, 1, data, regs); | |
7592 | } else | |
7593 | data->period = event->hw.last_period; | |
7594 | ||
0cff784a | 7595 | if (nr == 1 && hwc->sample_period == 1 && !event->attr.freq) |
a8b0ca17 | 7596 | return perf_swevent_overflow(event, 1, data, regs); |
0cff784a | 7597 | |
e7850595 | 7598 | if (local64_add_negative(nr, &hwc->period_left)) |
7b4b6658 | 7599 | return; |
df1a132b | 7600 | |
a8b0ca17 | 7601 | perf_swevent_overflow(event, 0, data, regs); |
d6d020e9 PZ |
7602 | } |
7603 | ||
f5ffe02e FW |
7604 | static int perf_exclude_event(struct perf_event *event, |
7605 | struct pt_regs *regs) | |
7606 | { | |
a4eaf7f1 | 7607 | if (event->hw.state & PERF_HES_STOPPED) |
91b2f482 | 7608 | return 1; |
a4eaf7f1 | 7609 | |
f5ffe02e FW |
7610 | if (regs) { |
7611 | if (event->attr.exclude_user && user_mode(regs)) | |
7612 | return 1; | |
7613 | ||
7614 | if (event->attr.exclude_kernel && !user_mode(regs)) | |
7615 | return 1; | |
7616 | } | |
7617 | ||
7618 | return 0; | |
7619 | } | |
7620 | ||
cdd6c482 | 7621 | static int perf_swevent_match(struct perf_event *event, |
1c432d89 | 7622 | enum perf_type_id type, |
6fb2915d LZ |
7623 | u32 event_id, |
7624 | struct perf_sample_data *data, | |
7625 | struct pt_regs *regs) | |
15dbf27c | 7626 | { |
cdd6c482 | 7627 | if (event->attr.type != type) |
a21ca2ca | 7628 | return 0; |
f5ffe02e | 7629 | |
cdd6c482 | 7630 | if (event->attr.config != event_id) |
15dbf27c PZ |
7631 | return 0; |
7632 | ||
f5ffe02e FW |
7633 | if (perf_exclude_event(event, regs)) |
7634 | return 0; | |
15dbf27c PZ |
7635 | |
7636 | return 1; | |
7637 | } | |
7638 | ||
76e1d904 FW |
7639 | static inline u64 swevent_hash(u64 type, u32 event_id) |
7640 | { | |
7641 | u64 val = event_id | (type << 32); | |
7642 | ||
7643 | return hash_64(val, SWEVENT_HLIST_BITS); | |
7644 | } | |
7645 | ||
49f135ed FW |
7646 | static inline struct hlist_head * |
7647 | __find_swevent_head(struct swevent_hlist *hlist, u64 type, u32 event_id) | |
76e1d904 | 7648 | { |
49f135ed FW |
7649 | u64 hash = swevent_hash(type, event_id); |
7650 | ||
7651 | return &hlist->heads[hash]; | |
7652 | } | |
76e1d904 | 7653 | |
49f135ed FW |
7654 | /* For the read side: events when they trigger */ |
7655 | static inline struct hlist_head * | |
b28ab83c | 7656 | find_swevent_head_rcu(struct swevent_htable *swhash, u64 type, u32 event_id) |
49f135ed FW |
7657 | { |
7658 | struct swevent_hlist *hlist; | |
76e1d904 | 7659 | |
b28ab83c | 7660 | hlist = rcu_dereference(swhash->swevent_hlist); |
76e1d904 FW |
7661 | if (!hlist) |
7662 | return NULL; | |
7663 | ||
49f135ed FW |
7664 | return __find_swevent_head(hlist, type, event_id); |
7665 | } | |
7666 | ||
7667 | /* For the event head insertion and removal in the hlist */ | |
7668 | static inline struct hlist_head * | |
b28ab83c | 7669 | find_swevent_head(struct swevent_htable *swhash, struct perf_event *event) |
49f135ed FW |
7670 | { |
7671 | struct swevent_hlist *hlist; | |
7672 | u32 event_id = event->attr.config; | |
7673 | u64 type = event->attr.type; | |
7674 | ||
7675 | /* | |
7676 | * Event scheduling is always serialized against hlist allocation | |
7677 | * and release. Which makes the protected version suitable here. | |
7678 | * The context lock guarantees that. | |
7679 | */ | |
b28ab83c | 7680 | hlist = rcu_dereference_protected(swhash->swevent_hlist, |
49f135ed FW |
7681 | lockdep_is_held(&event->ctx->lock)); |
7682 | if (!hlist) | |
7683 | return NULL; | |
7684 | ||
7685 | return __find_swevent_head(hlist, type, event_id); | |
76e1d904 FW |
7686 | } |
7687 | ||
7688 | static void do_perf_sw_event(enum perf_type_id type, u32 event_id, | |
a8b0ca17 | 7689 | u64 nr, |
76e1d904 FW |
7690 | struct perf_sample_data *data, |
7691 | struct pt_regs *regs) | |
15dbf27c | 7692 | { |
4a32fea9 | 7693 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 7694 | struct perf_event *event; |
76e1d904 | 7695 | struct hlist_head *head; |
15dbf27c | 7696 | |
76e1d904 | 7697 | rcu_read_lock(); |
b28ab83c | 7698 | head = find_swevent_head_rcu(swhash, type, event_id); |
76e1d904 FW |
7699 | if (!head) |
7700 | goto end; | |
7701 | ||
b67bfe0d | 7702 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
6fb2915d | 7703 | if (perf_swevent_match(event, type, event_id, data, regs)) |
a8b0ca17 | 7704 | perf_swevent_event(event, nr, data, regs); |
15dbf27c | 7705 | } |
76e1d904 FW |
7706 | end: |
7707 | rcu_read_unlock(); | |
15dbf27c PZ |
7708 | } |
7709 | ||
86038c5e PZI |
7710 | DEFINE_PER_CPU(struct pt_regs, __perf_regs[4]); |
7711 | ||
4ed7c92d | 7712 | int perf_swevent_get_recursion_context(void) |
96f6d444 | 7713 | { |
4a32fea9 | 7714 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
96f6d444 | 7715 | |
b28ab83c | 7716 | return get_recursion_context(swhash->recursion); |
96f6d444 | 7717 | } |
645e8cc0 | 7718 | EXPORT_SYMBOL_GPL(perf_swevent_get_recursion_context); |
96f6d444 | 7719 | |
98b5c2c6 | 7720 | void perf_swevent_put_recursion_context(int rctx) |
15dbf27c | 7721 | { |
4a32fea9 | 7722 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
927c7a9e | 7723 | |
b28ab83c | 7724 | put_recursion_context(swhash->recursion, rctx); |
ce71b9df | 7725 | } |
15dbf27c | 7726 | |
86038c5e | 7727 | void ___perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) |
b8e83514 | 7728 | { |
a4234bfc | 7729 | struct perf_sample_data data; |
4ed7c92d | 7730 | |
86038c5e | 7731 | if (WARN_ON_ONCE(!regs)) |
4ed7c92d | 7732 | return; |
a4234bfc | 7733 | |
fd0d000b | 7734 | perf_sample_data_init(&data, addr, 0); |
a8b0ca17 | 7735 | do_perf_sw_event(PERF_TYPE_SOFTWARE, event_id, nr, &data, regs); |
86038c5e PZI |
7736 | } |
7737 | ||
7738 | void __perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) | |
7739 | { | |
7740 | int rctx; | |
7741 | ||
7742 | preempt_disable_notrace(); | |
7743 | rctx = perf_swevent_get_recursion_context(); | |
7744 | if (unlikely(rctx < 0)) | |
7745 | goto fail; | |
7746 | ||
7747 | ___perf_sw_event(event_id, nr, regs, addr); | |
4ed7c92d PZ |
7748 | |
7749 | perf_swevent_put_recursion_context(rctx); | |
86038c5e | 7750 | fail: |
1c024eca | 7751 | preempt_enable_notrace(); |
b8e83514 PZ |
7752 | } |
7753 | ||
cdd6c482 | 7754 | static void perf_swevent_read(struct perf_event *event) |
15dbf27c | 7755 | { |
15dbf27c PZ |
7756 | } |
7757 | ||
a4eaf7f1 | 7758 | static int perf_swevent_add(struct perf_event *event, int flags) |
15dbf27c | 7759 | { |
4a32fea9 | 7760 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 7761 | struct hw_perf_event *hwc = &event->hw; |
76e1d904 FW |
7762 | struct hlist_head *head; |
7763 | ||
6c7e550f | 7764 | if (is_sampling_event(event)) { |
7b4b6658 | 7765 | hwc->last_period = hwc->sample_period; |
cdd6c482 | 7766 | perf_swevent_set_period(event); |
7b4b6658 | 7767 | } |
76e1d904 | 7768 | |
a4eaf7f1 PZ |
7769 | hwc->state = !(flags & PERF_EF_START); |
7770 | ||
b28ab83c | 7771 | head = find_swevent_head(swhash, event); |
12ca6ad2 | 7772 | if (WARN_ON_ONCE(!head)) |
76e1d904 FW |
7773 | return -EINVAL; |
7774 | ||
7775 | hlist_add_head_rcu(&event->hlist_entry, head); | |
6a694a60 | 7776 | perf_event_update_userpage(event); |
76e1d904 | 7777 | |
15dbf27c PZ |
7778 | return 0; |
7779 | } | |
7780 | ||
a4eaf7f1 | 7781 | static void perf_swevent_del(struct perf_event *event, int flags) |
15dbf27c | 7782 | { |
76e1d904 | 7783 | hlist_del_rcu(&event->hlist_entry); |
15dbf27c PZ |
7784 | } |
7785 | ||
a4eaf7f1 | 7786 | static void perf_swevent_start(struct perf_event *event, int flags) |
5c92d124 | 7787 | { |
a4eaf7f1 | 7788 | event->hw.state = 0; |
d6d020e9 | 7789 | } |
aa9c4c0f | 7790 | |
a4eaf7f1 | 7791 | static void perf_swevent_stop(struct perf_event *event, int flags) |
d6d020e9 | 7792 | { |
a4eaf7f1 | 7793 | event->hw.state = PERF_HES_STOPPED; |
bae43c99 IM |
7794 | } |
7795 | ||
49f135ed FW |
7796 | /* Deref the hlist from the update side */ |
7797 | static inline struct swevent_hlist * | |
b28ab83c | 7798 | swevent_hlist_deref(struct swevent_htable *swhash) |
49f135ed | 7799 | { |
b28ab83c PZ |
7800 | return rcu_dereference_protected(swhash->swevent_hlist, |
7801 | lockdep_is_held(&swhash->hlist_mutex)); | |
49f135ed FW |
7802 | } |
7803 | ||
b28ab83c | 7804 | static void swevent_hlist_release(struct swevent_htable *swhash) |
76e1d904 | 7805 | { |
b28ab83c | 7806 | struct swevent_hlist *hlist = swevent_hlist_deref(swhash); |
76e1d904 | 7807 | |
49f135ed | 7808 | if (!hlist) |
76e1d904 FW |
7809 | return; |
7810 | ||
70691d4a | 7811 | RCU_INIT_POINTER(swhash->swevent_hlist, NULL); |
fa4bbc4c | 7812 | kfree_rcu(hlist, rcu_head); |
76e1d904 FW |
7813 | } |
7814 | ||
3b364d7b | 7815 | static void swevent_hlist_put_cpu(int cpu) |
76e1d904 | 7816 | { |
b28ab83c | 7817 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 | 7818 | |
b28ab83c | 7819 | mutex_lock(&swhash->hlist_mutex); |
76e1d904 | 7820 | |
b28ab83c PZ |
7821 | if (!--swhash->hlist_refcount) |
7822 | swevent_hlist_release(swhash); | |
76e1d904 | 7823 | |
b28ab83c | 7824 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
7825 | } |
7826 | ||
3b364d7b | 7827 | static void swevent_hlist_put(void) |
76e1d904 FW |
7828 | { |
7829 | int cpu; | |
7830 | ||
76e1d904 | 7831 | for_each_possible_cpu(cpu) |
3b364d7b | 7832 | swevent_hlist_put_cpu(cpu); |
76e1d904 FW |
7833 | } |
7834 | ||
3b364d7b | 7835 | static int swevent_hlist_get_cpu(int cpu) |
76e1d904 | 7836 | { |
b28ab83c | 7837 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 FW |
7838 | int err = 0; |
7839 | ||
b28ab83c | 7840 | mutex_lock(&swhash->hlist_mutex); |
a63fbed7 TG |
7841 | if (!swevent_hlist_deref(swhash) && |
7842 | cpumask_test_cpu(cpu, perf_online_mask)) { | |
76e1d904 FW |
7843 | struct swevent_hlist *hlist; |
7844 | ||
7845 | hlist = kzalloc(sizeof(*hlist), GFP_KERNEL); | |
7846 | if (!hlist) { | |
7847 | err = -ENOMEM; | |
7848 | goto exit; | |
7849 | } | |
b28ab83c | 7850 | rcu_assign_pointer(swhash->swevent_hlist, hlist); |
76e1d904 | 7851 | } |
b28ab83c | 7852 | swhash->hlist_refcount++; |
9ed6060d | 7853 | exit: |
b28ab83c | 7854 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
7855 | |
7856 | return err; | |
7857 | } | |
7858 | ||
3b364d7b | 7859 | static int swevent_hlist_get(void) |
76e1d904 | 7860 | { |
3b364d7b | 7861 | int err, cpu, failed_cpu; |
76e1d904 | 7862 | |
a63fbed7 | 7863 | mutex_lock(&pmus_lock); |
76e1d904 | 7864 | for_each_possible_cpu(cpu) { |
3b364d7b | 7865 | err = swevent_hlist_get_cpu(cpu); |
76e1d904 FW |
7866 | if (err) { |
7867 | failed_cpu = cpu; | |
7868 | goto fail; | |
7869 | } | |
7870 | } | |
a63fbed7 | 7871 | mutex_unlock(&pmus_lock); |
76e1d904 | 7872 | return 0; |
9ed6060d | 7873 | fail: |
76e1d904 FW |
7874 | for_each_possible_cpu(cpu) { |
7875 | if (cpu == failed_cpu) | |
7876 | break; | |
3b364d7b | 7877 | swevent_hlist_put_cpu(cpu); |
76e1d904 | 7878 | } |
a63fbed7 | 7879 | mutex_unlock(&pmus_lock); |
76e1d904 FW |
7880 | return err; |
7881 | } | |
7882 | ||
c5905afb | 7883 | struct static_key perf_swevent_enabled[PERF_COUNT_SW_MAX]; |
95476b64 | 7884 | |
b0a873eb PZ |
7885 | static void sw_perf_event_destroy(struct perf_event *event) |
7886 | { | |
7887 | u64 event_id = event->attr.config; | |
95476b64 | 7888 | |
b0a873eb PZ |
7889 | WARN_ON(event->parent); |
7890 | ||
c5905afb | 7891 | static_key_slow_dec(&perf_swevent_enabled[event_id]); |
3b364d7b | 7892 | swevent_hlist_put(); |
b0a873eb PZ |
7893 | } |
7894 | ||
7895 | static int perf_swevent_init(struct perf_event *event) | |
7896 | { | |
8176cced | 7897 | u64 event_id = event->attr.config; |
b0a873eb PZ |
7898 | |
7899 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
7900 | return -ENOENT; | |
7901 | ||
2481c5fa SE |
7902 | /* |
7903 | * no branch sampling for software events | |
7904 | */ | |
7905 | if (has_branch_stack(event)) | |
7906 | return -EOPNOTSUPP; | |
7907 | ||
b0a873eb PZ |
7908 | switch (event_id) { |
7909 | case PERF_COUNT_SW_CPU_CLOCK: | |
7910 | case PERF_COUNT_SW_TASK_CLOCK: | |
7911 | return -ENOENT; | |
7912 | ||
7913 | default: | |
7914 | break; | |
7915 | } | |
7916 | ||
ce677831 | 7917 | if (event_id >= PERF_COUNT_SW_MAX) |
b0a873eb PZ |
7918 | return -ENOENT; |
7919 | ||
7920 | if (!event->parent) { | |
7921 | int err; | |
7922 | ||
3b364d7b | 7923 | err = swevent_hlist_get(); |
b0a873eb PZ |
7924 | if (err) |
7925 | return err; | |
7926 | ||
c5905afb | 7927 | static_key_slow_inc(&perf_swevent_enabled[event_id]); |
b0a873eb PZ |
7928 | event->destroy = sw_perf_event_destroy; |
7929 | } | |
7930 | ||
7931 | return 0; | |
7932 | } | |
7933 | ||
7934 | static struct pmu perf_swevent = { | |
89a1e187 | 7935 | .task_ctx_nr = perf_sw_context, |
95476b64 | 7936 | |
34f43927 PZ |
7937 | .capabilities = PERF_PMU_CAP_NO_NMI, |
7938 | ||
b0a873eb | 7939 | .event_init = perf_swevent_init, |
a4eaf7f1 PZ |
7940 | .add = perf_swevent_add, |
7941 | .del = perf_swevent_del, | |
7942 | .start = perf_swevent_start, | |
7943 | .stop = perf_swevent_stop, | |
1c024eca | 7944 | .read = perf_swevent_read, |
1c024eca PZ |
7945 | }; |
7946 | ||
b0a873eb PZ |
7947 | #ifdef CONFIG_EVENT_TRACING |
7948 | ||
1c024eca PZ |
7949 | static int perf_tp_filter_match(struct perf_event *event, |
7950 | struct perf_sample_data *data) | |
7951 | { | |
7e3f977e | 7952 | void *record = data->raw->frag.data; |
1c024eca | 7953 | |
b71b437e PZ |
7954 | /* only top level events have filters set */ |
7955 | if (event->parent) | |
7956 | event = event->parent; | |
7957 | ||
1c024eca PZ |
7958 | if (likely(!event->filter) || filter_match_preds(event->filter, record)) |
7959 | return 1; | |
7960 | return 0; | |
7961 | } | |
7962 | ||
7963 | static int perf_tp_event_match(struct perf_event *event, | |
7964 | struct perf_sample_data *data, | |
7965 | struct pt_regs *regs) | |
7966 | { | |
a0f7d0f7 FW |
7967 | if (event->hw.state & PERF_HES_STOPPED) |
7968 | return 0; | |
580d607c PZ |
7969 | /* |
7970 | * All tracepoints are from kernel-space. | |
7971 | */ | |
7972 | if (event->attr.exclude_kernel) | |
1c024eca PZ |
7973 | return 0; |
7974 | ||
7975 | if (!perf_tp_filter_match(event, data)) | |
7976 | return 0; | |
7977 | ||
7978 | return 1; | |
7979 | } | |
7980 | ||
85b67bcb AS |
7981 | void perf_trace_run_bpf_submit(void *raw_data, int size, int rctx, |
7982 | struct trace_event_call *call, u64 count, | |
7983 | struct pt_regs *regs, struct hlist_head *head, | |
7984 | struct task_struct *task) | |
7985 | { | |
e87c6bc3 | 7986 | if (bpf_prog_array_valid(call)) { |
85b67bcb | 7987 | *(struct pt_regs **)raw_data = regs; |
e87c6bc3 | 7988 | if (!trace_call_bpf(call, raw_data) || hlist_empty(head)) { |
85b67bcb AS |
7989 | perf_swevent_put_recursion_context(rctx); |
7990 | return; | |
7991 | } | |
7992 | } | |
7993 | perf_tp_event(call->event.type, count, raw_data, size, regs, head, | |
8fd0fbbe | 7994 | rctx, task); |
85b67bcb AS |
7995 | } |
7996 | EXPORT_SYMBOL_GPL(perf_trace_run_bpf_submit); | |
7997 | ||
1e1dcd93 | 7998 | void perf_tp_event(u16 event_type, u64 count, void *record, int entry_size, |
e6dab5ff | 7999 | struct pt_regs *regs, struct hlist_head *head, int rctx, |
8fd0fbbe | 8000 | struct task_struct *task) |
95476b64 FW |
8001 | { |
8002 | struct perf_sample_data data; | |
8fd0fbbe | 8003 | struct perf_event *event; |
1c024eca | 8004 | |
95476b64 | 8005 | struct perf_raw_record raw = { |
7e3f977e DB |
8006 | .frag = { |
8007 | .size = entry_size, | |
8008 | .data = record, | |
8009 | }, | |
95476b64 FW |
8010 | }; |
8011 | ||
1e1dcd93 | 8012 | perf_sample_data_init(&data, 0, 0); |
95476b64 FW |
8013 | data.raw = &raw; |
8014 | ||
1e1dcd93 AS |
8015 | perf_trace_buf_update(record, event_type); |
8016 | ||
8fd0fbbe | 8017 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
1c024eca | 8018 | if (perf_tp_event_match(event, &data, regs)) |
a8b0ca17 | 8019 | perf_swevent_event(event, count, &data, regs); |
4f41c013 | 8020 | } |
ecc55f84 | 8021 | |
e6dab5ff AV |
8022 | /* |
8023 | * If we got specified a target task, also iterate its context and | |
8024 | * deliver this event there too. | |
8025 | */ | |
8026 | if (task && task != current) { | |
8027 | struct perf_event_context *ctx; | |
8028 | struct trace_entry *entry = record; | |
8029 | ||
8030 | rcu_read_lock(); | |
8031 | ctx = rcu_dereference(task->perf_event_ctxp[perf_sw_context]); | |
8032 | if (!ctx) | |
8033 | goto unlock; | |
8034 | ||
8035 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
ee2d3a8c JO |
8036 | if (event->cpu != smp_processor_id()) |
8037 | continue; | |
e6dab5ff AV |
8038 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
8039 | continue; | |
8040 | if (event->attr.config != entry->type) | |
8041 | continue; | |
8042 | if (perf_tp_event_match(event, &data, regs)) | |
8043 | perf_swevent_event(event, count, &data, regs); | |
8044 | } | |
8045 | unlock: | |
8046 | rcu_read_unlock(); | |
8047 | } | |
8048 | ||
ecc55f84 | 8049 | perf_swevent_put_recursion_context(rctx); |
95476b64 FW |
8050 | } |
8051 | EXPORT_SYMBOL_GPL(perf_tp_event); | |
8052 | ||
cdd6c482 | 8053 | static void tp_perf_event_destroy(struct perf_event *event) |
e077df4f | 8054 | { |
1c024eca | 8055 | perf_trace_destroy(event); |
e077df4f PZ |
8056 | } |
8057 | ||
b0a873eb | 8058 | static int perf_tp_event_init(struct perf_event *event) |
e077df4f | 8059 | { |
76e1d904 FW |
8060 | int err; |
8061 | ||
b0a873eb PZ |
8062 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
8063 | return -ENOENT; | |
8064 | ||
2481c5fa SE |
8065 | /* |
8066 | * no branch sampling for tracepoint events | |
8067 | */ | |
8068 | if (has_branch_stack(event)) | |
8069 | return -EOPNOTSUPP; | |
8070 | ||
1c024eca PZ |
8071 | err = perf_trace_init(event); |
8072 | if (err) | |
b0a873eb | 8073 | return err; |
e077df4f | 8074 | |
cdd6c482 | 8075 | event->destroy = tp_perf_event_destroy; |
e077df4f | 8076 | |
b0a873eb PZ |
8077 | return 0; |
8078 | } | |
8079 | ||
8080 | static struct pmu perf_tracepoint = { | |
89a1e187 PZ |
8081 | .task_ctx_nr = perf_sw_context, |
8082 | ||
b0a873eb | 8083 | .event_init = perf_tp_event_init, |
a4eaf7f1 PZ |
8084 | .add = perf_trace_add, |
8085 | .del = perf_trace_del, | |
8086 | .start = perf_swevent_start, | |
8087 | .stop = perf_swevent_stop, | |
b0a873eb | 8088 | .read = perf_swevent_read, |
b0a873eb PZ |
8089 | }; |
8090 | ||
8091 | static inline void perf_tp_register(void) | |
8092 | { | |
2e80a82a | 8093 | perf_pmu_register(&perf_tracepoint, "tracepoint", PERF_TYPE_TRACEPOINT); |
e077df4f | 8094 | } |
6fb2915d | 8095 | |
6fb2915d LZ |
8096 | static void perf_event_free_filter(struct perf_event *event) |
8097 | { | |
8098 | ftrace_profile_free_filter(event); | |
8099 | } | |
8100 | ||
aa6a5f3c AS |
8101 | #ifdef CONFIG_BPF_SYSCALL |
8102 | static void bpf_overflow_handler(struct perf_event *event, | |
8103 | struct perf_sample_data *data, | |
8104 | struct pt_regs *regs) | |
8105 | { | |
8106 | struct bpf_perf_event_data_kern ctx = { | |
8107 | .data = data, | |
7d9285e8 | 8108 | .event = event, |
aa6a5f3c AS |
8109 | }; |
8110 | int ret = 0; | |
8111 | ||
c895f6f7 | 8112 | ctx.regs = perf_arch_bpf_user_pt_regs(regs); |
aa6a5f3c AS |
8113 | preempt_disable(); |
8114 | if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) | |
8115 | goto out; | |
8116 | rcu_read_lock(); | |
88575199 | 8117 | ret = BPF_PROG_RUN(event->prog, &ctx); |
aa6a5f3c AS |
8118 | rcu_read_unlock(); |
8119 | out: | |
8120 | __this_cpu_dec(bpf_prog_active); | |
8121 | preempt_enable(); | |
8122 | if (!ret) | |
8123 | return; | |
8124 | ||
8125 | event->orig_overflow_handler(event, data, regs); | |
8126 | } | |
8127 | ||
8128 | static int perf_event_set_bpf_handler(struct perf_event *event, u32 prog_fd) | |
8129 | { | |
8130 | struct bpf_prog *prog; | |
8131 | ||
8132 | if (event->overflow_handler_context) | |
8133 | /* hw breakpoint or kernel counter */ | |
8134 | return -EINVAL; | |
8135 | ||
8136 | if (event->prog) | |
8137 | return -EEXIST; | |
8138 | ||
8139 | prog = bpf_prog_get_type(prog_fd, BPF_PROG_TYPE_PERF_EVENT); | |
8140 | if (IS_ERR(prog)) | |
8141 | return PTR_ERR(prog); | |
8142 | ||
8143 | event->prog = prog; | |
8144 | event->orig_overflow_handler = READ_ONCE(event->overflow_handler); | |
8145 | WRITE_ONCE(event->overflow_handler, bpf_overflow_handler); | |
8146 | return 0; | |
8147 | } | |
8148 | ||
8149 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
8150 | { | |
8151 | struct bpf_prog *prog = event->prog; | |
8152 | ||
8153 | if (!prog) | |
8154 | return; | |
8155 | ||
8156 | WRITE_ONCE(event->overflow_handler, event->orig_overflow_handler); | |
8157 | event->prog = NULL; | |
8158 | bpf_prog_put(prog); | |
8159 | } | |
8160 | #else | |
8161 | static int perf_event_set_bpf_handler(struct perf_event *event, u32 prog_fd) | |
8162 | { | |
8163 | return -EOPNOTSUPP; | |
8164 | } | |
8165 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
8166 | { | |
8167 | } | |
8168 | #endif | |
8169 | ||
2541517c AS |
8170 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
8171 | { | |
cf5f5cea | 8172 | bool is_kprobe, is_tracepoint, is_syscall_tp; |
2541517c | 8173 | struct bpf_prog *prog; |
e87c6bc3 | 8174 | int ret; |
2541517c AS |
8175 | |
8176 | if (event->attr.type != PERF_TYPE_TRACEPOINT) | |
f91840a3 | 8177 | return perf_event_set_bpf_handler(event, prog_fd); |
2541517c | 8178 | |
98b5c2c6 AS |
8179 | is_kprobe = event->tp_event->flags & TRACE_EVENT_FL_UKPROBE; |
8180 | is_tracepoint = event->tp_event->flags & TRACE_EVENT_FL_TRACEPOINT; | |
cf5f5cea YS |
8181 | is_syscall_tp = is_syscall_trace_event(event->tp_event); |
8182 | if (!is_kprobe && !is_tracepoint && !is_syscall_tp) | |
98b5c2c6 | 8183 | /* bpf programs can only be attached to u/kprobe or tracepoint */ |
2541517c AS |
8184 | return -EINVAL; |
8185 | ||
8186 | prog = bpf_prog_get(prog_fd); | |
8187 | if (IS_ERR(prog)) | |
8188 | return PTR_ERR(prog); | |
8189 | ||
98b5c2c6 | 8190 | if ((is_kprobe && prog->type != BPF_PROG_TYPE_KPROBE) || |
cf5f5cea YS |
8191 | (is_tracepoint && prog->type != BPF_PROG_TYPE_TRACEPOINT) || |
8192 | (is_syscall_tp && prog->type != BPF_PROG_TYPE_TRACEPOINT)) { | |
2541517c AS |
8193 | /* valid fd, but invalid bpf program type */ |
8194 | bpf_prog_put(prog); | |
8195 | return -EINVAL; | |
8196 | } | |
8197 | ||
cf5f5cea | 8198 | if (is_tracepoint || is_syscall_tp) { |
32bbe007 AS |
8199 | int off = trace_event_get_offsets(event->tp_event); |
8200 | ||
8201 | if (prog->aux->max_ctx_offset > off) { | |
8202 | bpf_prog_put(prog); | |
8203 | return -EACCES; | |
8204 | } | |
8205 | } | |
2541517c | 8206 | |
e87c6bc3 YS |
8207 | ret = perf_event_attach_bpf_prog(event, prog); |
8208 | if (ret) | |
8209 | bpf_prog_put(prog); | |
8210 | return ret; | |
2541517c AS |
8211 | } |
8212 | ||
8213 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
8214 | { | |
0b4c6841 YS |
8215 | if (event->attr.type != PERF_TYPE_TRACEPOINT) { |
8216 | perf_event_free_bpf_handler(event); | |
2541517c | 8217 | return; |
2541517c | 8218 | } |
e87c6bc3 | 8219 | perf_event_detach_bpf_prog(event); |
2541517c AS |
8220 | } |
8221 | ||
e077df4f | 8222 | #else |
6fb2915d | 8223 | |
b0a873eb | 8224 | static inline void perf_tp_register(void) |
e077df4f | 8225 | { |
e077df4f | 8226 | } |
6fb2915d | 8227 | |
6fb2915d LZ |
8228 | static void perf_event_free_filter(struct perf_event *event) |
8229 | { | |
8230 | } | |
8231 | ||
2541517c AS |
8232 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
8233 | { | |
8234 | return -ENOENT; | |
8235 | } | |
8236 | ||
8237 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
8238 | { | |
8239 | } | |
07b139c8 | 8240 | #endif /* CONFIG_EVENT_TRACING */ |
e077df4f | 8241 | |
24f1e32c | 8242 | #ifdef CONFIG_HAVE_HW_BREAKPOINT |
f5ffe02e | 8243 | void perf_bp_event(struct perf_event *bp, void *data) |
24f1e32c | 8244 | { |
f5ffe02e FW |
8245 | struct perf_sample_data sample; |
8246 | struct pt_regs *regs = data; | |
8247 | ||
fd0d000b | 8248 | perf_sample_data_init(&sample, bp->attr.bp_addr, 0); |
f5ffe02e | 8249 | |
a4eaf7f1 | 8250 | if (!bp->hw.state && !perf_exclude_event(bp, regs)) |
a8b0ca17 | 8251 | perf_swevent_event(bp, 1, &sample, regs); |
24f1e32c FW |
8252 | } |
8253 | #endif | |
8254 | ||
375637bc AS |
8255 | /* |
8256 | * Allocate a new address filter | |
8257 | */ | |
8258 | static struct perf_addr_filter * | |
8259 | perf_addr_filter_new(struct perf_event *event, struct list_head *filters) | |
8260 | { | |
8261 | int node = cpu_to_node(event->cpu == -1 ? 0 : event->cpu); | |
8262 | struct perf_addr_filter *filter; | |
8263 | ||
8264 | filter = kzalloc_node(sizeof(*filter), GFP_KERNEL, node); | |
8265 | if (!filter) | |
8266 | return NULL; | |
8267 | ||
8268 | INIT_LIST_HEAD(&filter->entry); | |
8269 | list_add_tail(&filter->entry, filters); | |
8270 | ||
8271 | return filter; | |
8272 | } | |
8273 | ||
8274 | static void free_filters_list(struct list_head *filters) | |
8275 | { | |
8276 | struct perf_addr_filter *filter, *iter; | |
8277 | ||
8278 | list_for_each_entry_safe(filter, iter, filters, entry) { | |
8279 | if (filter->inode) | |
8280 | iput(filter->inode); | |
8281 | list_del(&filter->entry); | |
8282 | kfree(filter); | |
8283 | } | |
8284 | } | |
8285 | ||
8286 | /* | |
8287 | * Free existing address filters and optionally install new ones | |
8288 | */ | |
8289 | static void perf_addr_filters_splice(struct perf_event *event, | |
8290 | struct list_head *head) | |
8291 | { | |
8292 | unsigned long flags; | |
8293 | LIST_HEAD(list); | |
8294 | ||
8295 | if (!has_addr_filter(event)) | |
8296 | return; | |
8297 | ||
8298 | /* don't bother with children, they don't have their own filters */ | |
8299 | if (event->parent) | |
8300 | return; | |
8301 | ||
8302 | raw_spin_lock_irqsave(&event->addr_filters.lock, flags); | |
8303 | ||
8304 | list_splice_init(&event->addr_filters.list, &list); | |
8305 | if (head) | |
8306 | list_splice(head, &event->addr_filters.list); | |
8307 | ||
8308 | raw_spin_unlock_irqrestore(&event->addr_filters.lock, flags); | |
8309 | ||
8310 | free_filters_list(&list); | |
8311 | } | |
8312 | ||
8313 | /* | |
8314 | * Scan through mm's vmas and see if one of them matches the | |
8315 | * @filter; if so, adjust filter's address range. | |
8316 | * Called with mm::mmap_sem down for reading. | |
8317 | */ | |
8318 | static unsigned long perf_addr_filter_apply(struct perf_addr_filter *filter, | |
8319 | struct mm_struct *mm) | |
8320 | { | |
8321 | struct vm_area_struct *vma; | |
8322 | ||
8323 | for (vma = mm->mmap; vma; vma = vma->vm_next) { | |
8324 | struct file *file = vma->vm_file; | |
8325 | unsigned long off = vma->vm_pgoff << PAGE_SHIFT; | |
8326 | unsigned long vma_size = vma->vm_end - vma->vm_start; | |
8327 | ||
8328 | if (!file) | |
8329 | continue; | |
8330 | ||
8331 | if (!perf_addr_filter_match(filter, file, off, vma_size)) | |
8332 | continue; | |
8333 | ||
8334 | return vma->vm_start; | |
8335 | } | |
8336 | ||
8337 | return 0; | |
8338 | } | |
8339 | ||
8340 | /* | |
8341 | * Update event's address range filters based on the | |
8342 | * task's existing mappings, if any. | |
8343 | */ | |
8344 | static void perf_event_addr_filters_apply(struct perf_event *event) | |
8345 | { | |
8346 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
8347 | struct task_struct *task = READ_ONCE(event->ctx->task); | |
8348 | struct perf_addr_filter *filter; | |
8349 | struct mm_struct *mm = NULL; | |
8350 | unsigned int count = 0; | |
8351 | unsigned long flags; | |
8352 | ||
8353 | /* | |
8354 | * We may observe TASK_TOMBSTONE, which means that the event tear-down | |
8355 | * will stop on the parent's child_mutex that our caller is also holding | |
8356 | */ | |
8357 | if (task == TASK_TOMBSTONE) | |
8358 | return; | |
8359 | ||
6ce77bfd AS |
8360 | if (!ifh->nr_file_filters) |
8361 | return; | |
8362 | ||
375637bc AS |
8363 | mm = get_task_mm(event->ctx->task); |
8364 | if (!mm) | |
8365 | goto restart; | |
8366 | ||
8367 | down_read(&mm->mmap_sem); | |
8368 | ||
8369 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
8370 | list_for_each_entry(filter, &ifh->list, entry) { | |
8371 | event->addr_filters_offs[count] = 0; | |
8372 | ||
99f5bc9b MP |
8373 | /* |
8374 | * Adjust base offset if the filter is associated to a binary | |
8375 | * that needs to be mapped: | |
8376 | */ | |
8377 | if (filter->inode) | |
375637bc AS |
8378 | event->addr_filters_offs[count] = |
8379 | perf_addr_filter_apply(filter, mm); | |
8380 | ||
8381 | count++; | |
8382 | } | |
8383 | ||
8384 | event->addr_filters_gen++; | |
8385 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
8386 | ||
8387 | up_read(&mm->mmap_sem); | |
8388 | ||
8389 | mmput(mm); | |
8390 | ||
8391 | restart: | |
767ae086 | 8392 | perf_event_stop(event, 1); |
375637bc AS |
8393 | } |
8394 | ||
8395 | /* | |
8396 | * Address range filtering: limiting the data to certain | |
8397 | * instruction address ranges. Filters are ioctl()ed to us from | |
8398 | * userspace as ascii strings. | |
8399 | * | |
8400 | * Filter string format: | |
8401 | * | |
8402 | * ACTION RANGE_SPEC | |
8403 | * where ACTION is one of the | |
8404 | * * "filter": limit the trace to this region | |
8405 | * * "start": start tracing from this address | |
8406 | * * "stop": stop tracing at this address/region; | |
8407 | * RANGE_SPEC is | |
8408 | * * for kernel addresses: <start address>[/<size>] | |
8409 | * * for object files: <start address>[/<size>]@</path/to/object/file> | |
8410 | * | |
8411 | * if <size> is not specified, the range is treated as a single address. | |
8412 | */ | |
8413 | enum { | |
e96271f3 | 8414 | IF_ACT_NONE = -1, |
375637bc AS |
8415 | IF_ACT_FILTER, |
8416 | IF_ACT_START, | |
8417 | IF_ACT_STOP, | |
8418 | IF_SRC_FILE, | |
8419 | IF_SRC_KERNEL, | |
8420 | IF_SRC_FILEADDR, | |
8421 | IF_SRC_KERNELADDR, | |
8422 | }; | |
8423 | ||
8424 | enum { | |
8425 | IF_STATE_ACTION = 0, | |
8426 | IF_STATE_SOURCE, | |
8427 | IF_STATE_END, | |
8428 | }; | |
8429 | ||
8430 | static const match_table_t if_tokens = { | |
8431 | { IF_ACT_FILTER, "filter" }, | |
8432 | { IF_ACT_START, "start" }, | |
8433 | { IF_ACT_STOP, "stop" }, | |
8434 | { IF_SRC_FILE, "%u/%u@%s" }, | |
8435 | { IF_SRC_KERNEL, "%u/%u" }, | |
8436 | { IF_SRC_FILEADDR, "%u@%s" }, | |
8437 | { IF_SRC_KERNELADDR, "%u" }, | |
e96271f3 | 8438 | { IF_ACT_NONE, NULL }, |
375637bc AS |
8439 | }; |
8440 | ||
8441 | /* | |
8442 | * Address filter string parser | |
8443 | */ | |
8444 | static int | |
8445 | perf_event_parse_addr_filter(struct perf_event *event, char *fstr, | |
8446 | struct list_head *filters) | |
8447 | { | |
8448 | struct perf_addr_filter *filter = NULL; | |
8449 | char *start, *orig, *filename = NULL; | |
8450 | struct path path; | |
8451 | substring_t args[MAX_OPT_ARGS]; | |
8452 | int state = IF_STATE_ACTION, token; | |
8453 | unsigned int kernel = 0; | |
8454 | int ret = -EINVAL; | |
8455 | ||
8456 | orig = fstr = kstrdup(fstr, GFP_KERNEL); | |
8457 | if (!fstr) | |
8458 | return -ENOMEM; | |
8459 | ||
8460 | while ((start = strsep(&fstr, " ,\n")) != NULL) { | |
8461 | ret = -EINVAL; | |
8462 | ||
8463 | if (!*start) | |
8464 | continue; | |
8465 | ||
8466 | /* filter definition begins */ | |
8467 | if (state == IF_STATE_ACTION) { | |
8468 | filter = perf_addr_filter_new(event, filters); | |
8469 | if (!filter) | |
8470 | goto fail; | |
8471 | } | |
8472 | ||
8473 | token = match_token(start, if_tokens, args); | |
8474 | switch (token) { | |
8475 | case IF_ACT_FILTER: | |
8476 | case IF_ACT_START: | |
8477 | filter->filter = 1; | |
8478 | ||
8479 | case IF_ACT_STOP: | |
8480 | if (state != IF_STATE_ACTION) | |
8481 | goto fail; | |
8482 | ||
8483 | state = IF_STATE_SOURCE; | |
8484 | break; | |
8485 | ||
8486 | case IF_SRC_KERNELADDR: | |
8487 | case IF_SRC_KERNEL: | |
8488 | kernel = 1; | |
8489 | ||
8490 | case IF_SRC_FILEADDR: | |
8491 | case IF_SRC_FILE: | |
8492 | if (state != IF_STATE_SOURCE) | |
8493 | goto fail; | |
8494 | ||
8495 | if (token == IF_SRC_FILE || token == IF_SRC_KERNEL) | |
8496 | filter->range = 1; | |
8497 | ||
8498 | *args[0].to = 0; | |
8499 | ret = kstrtoul(args[0].from, 0, &filter->offset); | |
8500 | if (ret) | |
8501 | goto fail; | |
8502 | ||
8503 | if (filter->range) { | |
8504 | *args[1].to = 0; | |
8505 | ret = kstrtoul(args[1].from, 0, &filter->size); | |
8506 | if (ret) | |
8507 | goto fail; | |
8508 | } | |
8509 | ||
4059ffd0 MP |
8510 | if (token == IF_SRC_FILE || token == IF_SRC_FILEADDR) { |
8511 | int fpos = filter->range ? 2 : 1; | |
8512 | ||
8513 | filename = match_strdup(&args[fpos]); | |
375637bc AS |
8514 | if (!filename) { |
8515 | ret = -ENOMEM; | |
8516 | goto fail; | |
8517 | } | |
8518 | } | |
8519 | ||
8520 | state = IF_STATE_END; | |
8521 | break; | |
8522 | ||
8523 | default: | |
8524 | goto fail; | |
8525 | } | |
8526 | ||
8527 | /* | |
8528 | * Filter definition is fully parsed, validate and install it. | |
8529 | * Make sure that it doesn't contradict itself or the event's | |
8530 | * attribute. | |
8531 | */ | |
8532 | if (state == IF_STATE_END) { | |
9ccbfbb1 | 8533 | ret = -EINVAL; |
375637bc AS |
8534 | if (kernel && event->attr.exclude_kernel) |
8535 | goto fail; | |
8536 | ||
8537 | if (!kernel) { | |
8538 | if (!filename) | |
8539 | goto fail; | |
8540 | ||
6ce77bfd AS |
8541 | /* |
8542 | * For now, we only support file-based filters | |
8543 | * in per-task events; doing so for CPU-wide | |
8544 | * events requires additional context switching | |
8545 | * trickery, since same object code will be | |
8546 | * mapped at different virtual addresses in | |
8547 | * different processes. | |
8548 | */ | |
8549 | ret = -EOPNOTSUPP; | |
8550 | if (!event->ctx->task) | |
8551 | goto fail_free_name; | |
8552 | ||
375637bc AS |
8553 | /* look up the path and grab its inode */ |
8554 | ret = kern_path(filename, LOOKUP_FOLLOW, &path); | |
8555 | if (ret) | |
8556 | goto fail_free_name; | |
8557 | ||
8558 | filter->inode = igrab(d_inode(path.dentry)); | |
8559 | path_put(&path); | |
8560 | kfree(filename); | |
8561 | filename = NULL; | |
8562 | ||
8563 | ret = -EINVAL; | |
8564 | if (!filter->inode || | |
8565 | !S_ISREG(filter->inode->i_mode)) | |
8566 | /* free_filters_list() will iput() */ | |
8567 | goto fail; | |
6ce77bfd AS |
8568 | |
8569 | event->addr_filters.nr_file_filters++; | |
375637bc AS |
8570 | } |
8571 | ||
8572 | /* ready to consume more filters */ | |
8573 | state = IF_STATE_ACTION; | |
8574 | filter = NULL; | |
8575 | } | |
8576 | } | |
8577 | ||
8578 | if (state != IF_STATE_ACTION) | |
8579 | goto fail; | |
8580 | ||
8581 | kfree(orig); | |
8582 | ||
8583 | return 0; | |
8584 | ||
8585 | fail_free_name: | |
8586 | kfree(filename); | |
8587 | fail: | |
8588 | free_filters_list(filters); | |
8589 | kfree(orig); | |
8590 | ||
8591 | return ret; | |
8592 | } | |
8593 | ||
8594 | static int | |
8595 | perf_event_set_addr_filter(struct perf_event *event, char *filter_str) | |
8596 | { | |
8597 | LIST_HEAD(filters); | |
8598 | int ret; | |
8599 | ||
8600 | /* | |
8601 | * Since this is called in perf_ioctl() path, we're already holding | |
8602 | * ctx::mutex. | |
8603 | */ | |
8604 | lockdep_assert_held(&event->ctx->mutex); | |
8605 | ||
8606 | if (WARN_ON_ONCE(event->parent)) | |
8607 | return -EINVAL; | |
8608 | ||
375637bc AS |
8609 | ret = perf_event_parse_addr_filter(event, filter_str, &filters); |
8610 | if (ret) | |
6ce77bfd | 8611 | goto fail_clear_files; |
375637bc AS |
8612 | |
8613 | ret = event->pmu->addr_filters_validate(&filters); | |
6ce77bfd AS |
8614 | if (ret) |
8615 | goto fail_free_filters; | |
375637bc AS |
8616 | |
8617 | /* remove existing filters, if any */ | |
8618 | perf_addr_filters_splice(event, &filters); | |
8619 | ||
8620 | /* install new filters */ | |
8621 | perf_event_for_each_child(event, perf_event_addr_filters_apply); | |
8622 | ||
6ce77bfd AS |
8623 | return ret; |
8624 | ||
8625 | fail_free_filters: | |
8626 | free_filters_list(&filters); | |
8627 | ||
8628 | fail_clear_files: | |
8629 | event->addr_filters.nr_file_filters = 0; | |
8630 | ||
375637bc AS |
8631 | return ret; |
8632 | } | |
8633 | ||
43fa87f7 PZ |
8634 | static int |
8635 | perf_tracepoint_set_filter(struct perf_event *event, char *filter_str) | |
8636 | { | |
8637 | struct perf_event_context *ctx = event->ctx; | |
8638 | int ret; | |
8639 | ||
8640 | /* | |
8641 | * Beware, here be dragons!! | |
8642 | * | |
8643 | * the tracepoint muck will deadlock against ctx->mutex, but the tracepoint | |
8644 | * stuff does not actually need it. So temporarily drop ctx->mutex. As per | |
8645 | * perf_event_ctx_lock() we already have a reference on ctx. | |
8646 | * | |
8647 | * This can result in event getting moved to a different ctx, but that | |
8648 | * does not affect the tracepoint state. | |
8649 | */ | |
8650 | mutex_unlock(&ctx->mutex); | |
8651 | ret = ftrace_profile_set_filter(event, event->attr.config, filter_str); | |
8652 | mutex_lock(&ctx->mutex); | |
8653 | ||
8654 | return ret; | |
8655 | } | |
8656 | ||
c796bbbe AS |
8657 | static int perf_event_set_filter(struct perf_event *event, void __user *arg) |
8658 | { | |
8659 | char *filter_str; | |
8660 | int ret = -EINVAL; | |
8661 | ||
375637bc AS |
8662 | if ((event->attr.type != PERF_TYPE_TRACEPOINT || |
8663 | !IS_ENABLED(CONFIG_EVENT_TRACING)) && | |
8664 | !has_addr_filter(event)) | |
c796bbbe AS |
8665 | return -EINVAL; |
8666 | ||
8667 | filter_str = strndup_user(arg, PAGE_SIZE); | |
8668 | if (IS_ERR(filter_str)) | |
8669 | return PTR_ERR(filter_str); | |
8670 | ||
8671 | if (IS_ENABLED(CONFIG_EVENT_TRACING) && | |
8672 | event->attr.type == PERF_TYPE_TRACEPOINT) | |
43fa87f7 | 8673 | ret = perf_tracepoint_set_filter(event, filter_str); |
375637bc AS |
8674 | else if (has_addr_filter(event)) |
8675 | ret = perf_event_set_addr_filter(event, filter_str); | |
c796bbbe AS |
8676 | |
8677 | kfree(filter_str); | |
8678 | return ret; | |
8679 | } | |
8680 | ||
b0a873eb PZ |
8681 | /* |
8682 | * hrtimer based swevent callback | |
8683 | */ | |
f29ac756 | 8684 | |
b0a873eb | 8685 | static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer) |
f29ac756 | 8686 | { |
b0a873eb PZ |
8687 | enum hrtimer_restart ret = HRTIMER_RESTART; |
8688 | struct perf_sample_data data; | |
8689 | struct pt_regs *regs; | |
8690 | struct perf_event *event; | |
8691 | u64 period; | |
f29ac756 | 8692 | |
b0a873eb | 8693 | event = container_of(hrtimer, struct perf_event, hw.hrtimer); |
ba3dd36c PZ |
8694 | |
8695 | if (event->state != PERF_EVENT_STATE_ACTIVE) | |
8696 | return HRTIMER_NORESTART; | |
8697 | ||
b0a873eb | 8698 | event->pmu->read(event); |
f344011c | 8699 | |
fd0d000b | 8700 | perf_sample_data_init(&data, 0, event->hw.last_period); |
b0a873eb PZ |
8701 | regs = get_irq_regs(); |
8702 | ||
8703 | if (regs && !perf_exclude_event(event, regs)) { | |
77aeeebd | 8704 | if (!(event->attr.exclude_idle && is_idle_task(current))) |
33b07b8b | 8705 | if (__perf_event_overflow(event, 1, &data, regs)) |
b0a873eb PZ |
8706 | ret = HRTIMER_NORESTART; |
8707 | } | |
24f1e32c | 8708 | |
b0a873eb PZ |
8709 | period = max_t(u64, 10000, event->hw.sample_period); |
8710 | hrtimer_forward_now(hrtimer, ns_to_ktime(period)); | |
24f1e32c | 8711 | |
b0a873eb | 8712 | return ret; |
f29ac756 PZ |
8713 | } |
8714 | ||
b0a873eb | 8715 | static void perf_swevent_start_hrtimer(struct perf_event *event) |
5c92d124 | 8716 | { |
b0a873eb | 8717 | struct hw_perf_event *hwc = &event->hw; |
5d508e82 FBH |
8718 | s64 period; |
8719 | ||
8720 | if (!is_sampling_event(event)) | |
8721 | return; | |
f5ffe02e | 8722 | |
5d508e82 FBH |
8723 | period = local64_read(&hwc->period_left); |
8724 | if (period) { | |
8725 | if (period < 0) | |
8726 | period = 10000; | |
fa407f35 | 8727 | |
5d508e82 FBH |
8728 | local64_set(&hwc->period_left, 0); |
8729 | } else { | |
8730 | period = max_t(u64, 10000, hwc->sample_period); | |
8731 | } | |
3497d206 TG |
8732 | hrtimer_start(&hwc->hrtimer, ns_to_ktime(period), |
8733 | HRTIMER_MODE_REL_PINNED); | |
24f1e32c | 8734 | } |
b0a873eb PZ |
8735 | |
8736 | static void perf_swevent_cancel_hrtimer(struct perf_event *event) | |
24f1e32c | 8737 | { |
b0a873eb PZ |
8738 | struct hw_perf_event *hwc = &event->hw; |
8739 | ||
6c7e550f | 8740 | if (is_sampling_event(event)) { |
b0a873eb | 8741 | ktime_t remaining = hrtimer_get_remaining(&hwc->hrtimer); |
fa407f35 | 8742 | local64_set(&hwc->period_left, ktime_to_ns(remaining)); |
b0a873eb PZ |
8743 | |
8744 | hrtimer_cancel(&hwc->hrtimer); | |
8745 | } | |
24f1e32c FW |
8746 | } |
8747 | ||
ba3dd36c PZ |
8748 | static void perf_swevent_init_hrtimer(struct perf_event *event) |
8749 | { | |
8750 | struct hw_perf_event *hwc = &event->hw; | |
8751 | ||
8752 | if (!is_sampling_event(event)) | |
8753 | return; | |
8754 | ||
8755 | hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); | |
8756 | hwc->hrtimer.function = perf_swevent_hrtimer; | |
8757 | ||
8758 | /* | |
8759 | * Since hrtimers have a fixed rate, we can do a static freq->period | |
8760 | * mapping and avoid the whole period adjust feedback stuff. | |
8761 | */ | |
8762 | if (event->attr.freq) { | |
8763 | long freq = event->attr.sample_freq; | |
8764 | ||
8765 | event->attr.sample_period = NSEC_PER_SEC / freq; | |
8766 | hwc->sample_period = event->attr.sample_period; | |
8767 | local64_set(&hwc->period_left, hwc->sample_period); | |
778141e3 | 8768 | hwc->last_period = hwc->sample_period; |
ba3dd36c PZ |
8769 | event->attr.freq = 0; |
8770 | } | |
8771 | } | |
8772 | ||
b0a873eb PZ |
8773 | /* |
8774 | * Software event: cpu wall time clock | |
8775 | */ | |
8776 | ||
8777 | static void cpu_clock_event_update(struct perf_event *event) | |
24f1e32c | 8778 | { |
b0a873eb PZ |
8779 | s64 prev; |
8780 | u64 now; | |
8781 | ||
a4eaf7f1 | 8782 | now = local_clock(); |
b0a873eb PZ |
8783 | prev = local64_xchg(&event->hw.prev_count, now); |
8784 | local64_add(now - prev, &event->count); | |
24f1e32c | 8785 | } |
24f1e32c | 8786 | |
a4eaf7f1 | 8787 | static void cpu_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 8788 | { |
a4eaf7f1 | 8789 | local64_set(&event->hw.prev_count, local_clock()); |
b0a873eb | 8790 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
8791 | } |
8792 | ||
a4eaf7f1 | 8793 | static void cpu_clock_event_stop(struct perf_event *event, int flags) |
f29ac756 | 8794 | { |
b0a873eb PZ |
8795 | perf_swevent_cancel_hrtimer(event); |
8796 | cpu_clock_event_update(event); | |
8797 | } | |
f29ac756 | 8798 | |
a4eaf7f1 PZ |
8799 | static int cpu_clock_event_add(struct perf_event *event, int flags) |
8800 | { | |
8801 | if (flags & PERF_EF_START) | |
8802 | cpu_clock_event_start(event, flags); | |
6a694a60 | 8803 | perf_event_update_userpage(event); |
a4eaf7f1 PZ |
8804 | |
8805 | return 0; | |
8806 | } | |
8807 | ||
8808 | static void cpu_clock_event_del(struct perf_event *event, int flags) | |
8809 | { | |
8810 | cpu_clock_event_stop(event, flags); | |
8811 | } | |
8812 | ||
b0a873eb PZ |
8813 | static void cpu_clock_event_read(struct perf_event *event) |
8814 | { | |
8815 | cpu_clock_event_update(event); | |
8816 | } | |
f344011c | 8817 | |
b0a873eb PZ |
8818 | static int cpu_clock_event_init(struct perf_event *event) |
8819 | { | |
8820 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
8821 | return -ENOENT; | |
8822 | ||
8823 | if (event->attr.config != PERF_COUNT_SW_CPU_CLOCK) | |
8824 | return -ENOENT; | |
8825 | ||
2481c5fa SE |
8826 | /* |
8827 | * no branch sampling for software events | |
8828 | */ | |
8829 | if (has_branch_stack(event)) | |
8830 | return -EOPNOTSUPP; | |
8831 | ||
ba3dd36c PZ |
8832 | perf_swevent_init_hrtimer(event); |
8833 | ||
b0a873eb | 8834 | return 0; |
f29ac756 PZ |
8835 | } |
8836 | ||
b0a873eb | 8837 | static struct pmu perf_cpu_clock = { |
89a1e187 PZ |
8838 | .task_ctx_nr = perf_sw_context, |
8839 | ||
34f43927 PZ |
8840 | .capabilities = PERF_PMU_CAP_NO_NMI, |
8841 | ||
b0a873eb | 8842 | .event_init = cpu_clock_event_init, |
a4eaf7f1 PZ |
8843 | .add = cpu_clock_event_add, |
8844 | .del = cpu_clock_event_del, | |
8845 | .start = cpu_clock_event_start, | |
8846 | .stop = cpu_clock_event_stop, | |
b0a873eb PZ |
8847 | .read = cpu_clock_event_read, |
8848 | }; | |
8849 | ||
8850 | /* | |
8851 | * Software event: task time clock | |
8852 | */ | |
8853 | ||
8854 | static void task_clock_event_update(struct perf_event *event, u64 now) | |
5c92d124 | 8855 | { |
b0a873eb PZ |
8856 | u64 prev; |
8857 | s64 delta; | |
5c92d124 | 8858 | |
b0a873eb PZ |
8859 | prev = local64_xchg(&event->hw.prev_count, now); |
8860 | delta = now - prev; | |
8861 | local64_add(delta, &event->count); | |
8862 | } | |
5c92d124 | 8863 | |
a4eaf7f1 | 8864 | static void task_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 8865 | { |
a4eaf7f1 | 8866 | local64_set(&event->hw.prev_count, event->ctx->time); |
b0a873eb | 8867 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
8868 | } |
8869 | ||
a4eaf7f1 | 8870 | static void task_clock_event_stop(struct perf_event *event, int flags) |
b0a873eb PZ |
8871 | { |
8872 | perf_swevent_cancel_hrtimer(event); | |
8873 | task_clock_event_update(event, event->ctx->time); | |
a4eaf7f1 PZ |
8874 | } |
8875 | ||
8876 | static int task_clock_event_add(struct perf_event *event, int flags) | |
8877 | { | |
8878 | if (flags & PERF_EF_START) | |
8879 | task_clock_event_start(event, flags); | |
6a694a60 | 8880 | perf_event_update_userpage(event); |
b0a873eb | 8881 | |
a4eaf7f1 PZ |
8882 | return 0; |
8883 | } | |
8884 | ||
8885 | static void task_clock_event_del(struct perf_event *event, int flags) | |
8886 | { | |
8887 | task_clock_event_stop(event, PERF_EF_UPDATE); | |
b0a873eb PZ |
8888 | } |
8889 | ||
8890 | static void task_clock_event_read(struct perf_event *event) | |
8891 | { | |
768a06e2 PZ |
8892 | u64 now = perf_clock(); |
8893 | u64 delta = now - event->ctx->timestamp; | |
8894 | u64 time = event->ctx->time + delta; | |
b0a873eb PZ |
8895 | |
8896 | task_clock_event_update(event, time); | |
8897 | } | |
8898 | ||
8899 | static int task_clock_event_init(struct perf_event *event) | |
6fb2915d | 8900 | { |
b0a873eb PZ |
8901 | if (event->attr.type != PERF_TYPE_SOFTWARE) |
8902 | return -ENOENT; | |
8903 | ||
8904 | if (event->attr.config != PERF_COUNT_SW_TASK_CLOCK) | |
8905 | return -ENOENT; | |
8906 | ||
2481c5fa SE |
8907 | /* |
8908 | * no branch sampling for software events | |
8909 | */ | |
8910 | if (has_branch_stack(event)) | |
8911 | return -EOPNOTSUPP; | |
8912 | ||
ba3dd36c PZ |
8913 | perf_swevent_init_hrtimer(event); |
8914 | ||
b0a873eb | 8915 | return 0; |
6fb2915d LZ |
8916 | } |
8917 | ||
b0a873eb | 8918 | static struct pmu perf_task_clock = { |
89a1e187 PZ |
8919 | .task_ctx_nr = perf_sw_context, |
8920 | ||
34f43927 PZ |
8921 | .capabilities = PERF_PMU_CAP_NO_NMI, |
8922 | ||
b0a873eb | 8923 | .event_init = task_clock_event_init, |
a4eaf7f1 PZ |
8924 | .add = task_clock_event_add, |
8925 | .del = task_clock_event_del, | |
8926 | .start = task_clock_event_start, | |
8927 | .stop = task_clock_event_stop, | |
b0a873eb PZ |
8928 | .read = task_clock_event_read, |
8929 | }; | |
6fb2915d | 8930 | |
ad5133b7 | 8931 | static void perf_pmu_nop_void(struct pmu *pmu) |
e077df4f | 8932 | { |
e077df4f | 8933 | } |
6fb2915d | 8934 | |
fbbe0701 SB |
8935 | static void perf_pmu_nop_txn(struct pmu *pmu, unsigned int flags) |
8936 | { | |
8937 | } | |
8938 | ||
ad5133b7 | 8939 | static int perf_pmu_nop_int(struct pmu *pmu) |
6fb2915d | 8940 | { |
ad5133b7 | 8941 | return 0; |
6fb2915d LZ |
8942 | } |
8943 | ||
57f9f919 JO |
8944 | static int perf_event_nop_int(struct perf_event *event, u64 value) |
8945 | { | |
8946 | return 0; | |
8947 | } | |
8948 | ||
18ab2cd3 | 8949 | static DEFINE_PER_CPU(unsigned int, nop_txn_flags); |
fbbe0701 SB |
8950 | |
8951 | static void perf_pmu_start_txn(struct pmu *pmu, unsigned int flags) | |
6fb2915d | 8952 | { |
fbbe0701 SB |
8953 | __this_cpu_write(nop_txn_flags, flags); |
8954 | ||
8955 | if (flags & ~PERF_PMU_TXN_ADD) | |
8956 | return; | |
8957 | ||
ad5133b7 | 8958 | perf_pmu_disable(pmu); |
6fb2915d LZ |
8959 | } |
8960 | ||
ad5133b7 PZ |
8961 | static int perf_pmu_commit_txn(struct pmu *pmu) |
8962 | { | |
fbbe0701 SB |
8963 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
8964 | ||
8965 | __this_cpu_write(nop_txn_flags, 0); | |
8966 | ||
8967 | if (flags & ~PERF_PMU_TXN_ADD) | |
8968 | return 0; | |
8969 | ||
ad5133b7 PZ |
8970 | perf_pmu_enable(pmu); |
8971 | return 0; | |
8972 | } | |
e077df4f | 8973 | |
ad5133b7 | 8974 | static void perf_pmu_cancel_txn(struct pmu *pmu) |
24f1e32c | 8975 | { |
fbbe0701 SB |
8976 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
8977 | ||
8978 | __this_cpu_write(nop_txn_flags, 0); | |
8979 | ||
8980 | if (flags & ~PERF_PMU_TXN_ADD) | |
8981 | return; | |
8982 | ||
ad5133b7 | 8983 | perf_pmu_enable(pmu); |
24f1e32c FW |
8984 | } |
8985 | ||
35edc2a5 PZ |
8986 | static int perf_event_idx_default(struct perf_event *event) |
8987 | { | |
c719f560 | 8988 | return 0; |
35edc2a5 PZ |
8989 | } |
8990 | ||
8dc85d54 PZ |
8991 | /* |
8992 | * Ensures all contexts with the same task_ctx_nr have the same | |
8993 | * pmu_cpu_context too. | |
8994 | */ | |
9e317041 | 8995 | static struct perf_cpu_context __percpu *find_pmu_context(int ctxn) |
24f1e32c | 8996 | { |
8dc85d54 | 8997 | struct pmu *pmu; |
b326e956 | 8998 | |
8dc85d54 PZ |
8999 | if (ctxn < 0) |
9000 | return NULL; | |
24f1e32c | 9001 | |
8dc85d54 PZ |
9002 | list_for_each_entry(pmu, &pmus, entry) { |
9003 | if (pmu->task_ctx_nr == ctxn) | |
9004 | return pmu->pmu_cpu_context; | |
9005 | } | |
24f1e32c | 9006 | |
8dc85d54 | 9007 | return NULL; |
24f1e32c FW |
9008 | } |
9009 | ||
51676957 PZ |
9010 | static void free_pmu_context(struct pmu *pmu) |
9011 | { | |
df0062b2 WD |
9012 | /* |
9013 | * Static contexts such as perf_sw_context have a global lifetime | |
9014 | * and may be shared between different PMUs. Avoid freeing them | |
9015 | * when a single PMU is going away. | |
9016 | */ | |
9017 | if (pmu->task_ctx_nr > perf_invalid_context) | |
9018 | return; | |
9019 | ||
51676957 | 9020 | free_percpu(pmu->pmu_cpu_context); |
24f1e32c | 9021 | } |
6e855cd4 AS |
9022 | |
9023 | /* | |
9024 | * Let userspace know that this PMU supports address range filtering: | |
9025 | */ | |
9026 | static ssize_t nr_addr_filters_show(struct device *dev, | |
9027 | struct device_attribute *attr, | |
9028 | char *page) | |
9029 | { | |
9030 | struct pmu *pmu = dev_get_drvdata(dev); | |
9031 | ||
9032 | return snprintf(page, PAGE_SIZE - 1, "%d\n", pmu->nr_addr_filters); | |
9033 | } | |
9034 | DEVICE_ATTR_RO(nr_addr_filters); | |
9035 | ||
2e80a82a | 9036 | static struct idr pmu_idr; |
d6d020e9 | 9037 | |
abe43400 PZ |
9038 | static ssize_t |
9039 | type_show(struct device *dev, struct device_attribute *attr, char *page) | |
9040 | { | |
9041 | struct pmu *pmu = dev_get_drvdata(dev); | |
9042 | ||
9043 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->type); | |
9044 | } | |
90826ca7 | 9045 | static DEVICE_ATTR_RO(type); |
abe43400 | 9046 | |
62b85639 SE |
9047 | static ssize_t |
9048 | perf_event_mux_interval_ms_show(struct device *dev, | |
9049 | struct device_attribute *attr, | |
9050 | char *page) | |
9051 | { | |
9052 | struct pmu *pmu = dev_get_drvdata(dev); | |
9053 | ||
9054 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->hrtimer_interval_ms); | |
9055 | } | |
9056 | ||
272325c4 PZ |
9057 | static DEFINE_MUTEX(mux_interval_mutex); |
9058 | ||
62b85639 SE |
9059 | static ssize_t |
9060 | perf_event_mux_interval_ms_store(struct device *dev, | |
9061 | struct device_attribute *attr, | |
9062 | const char *buf, size_t count) | |
9063 | { | |
9064 | struct pmu *pmu = dev_get_drvdata(dev); | |
9065 | int timer, cpu, ret; | |
9066 | ||
9067 | ret = kstrtoint(buf, 0, &timer); | |
9068 | if (ret) | |
9069 | return ret; | |
9070 | ||
9071 | if (timer < 1) | |
9072 | return -EINVAL; | |
9073 | ||
9074 | /* same value, noting to do */ | |
9075 | if (timer == pmu->hrtimer_interval_ms) | |
9076 | return count; | |
9077 | ||
272325c4 | 9078 | mutex_lock(&mux_interval_mutex); |
62b85639 SE |
9079 | pmu->hrtimer_interval_ms = timer; |
9080 | ||
9081 | /* update all cpuctx for this PMU */ | |
a63fbed7 | 9082 | cpus_read_lock(); |
272325c4 | 9083 | for_each_online_cpu(cpu) { |
62b85639 SE |
9084 | struct perf_cpu_context *cpuctx; |
9085 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
9086 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * timer); | |
9087 | ||
272325c4 PZ |
9088 | cpu_function_call(cpu, |
9089 | (remote_function_f)perf_mux_hrtimer_restart, cpuctx); | |
62b85639 | 9090 | } |
a63fbed7 | 9091 | cpus_read_unlock(); |
272325c4 | 9092 | mutex_unlock(&mux_interval_mutex); |
62b85639 SE |
9093 | |
9094 | return count; | |
9095 | } | |
90826ca7 | 9096 | static DEVICE_ATTR_RW(perf_event_mux_interval_ms); |
62b85639 | 9097 | |
90826ca7 GKH |
9098 | static struct attribute *pmu_dev_attrs[] = { |
9099 | &dev_attr_type.attr, | |
9100 | &dev_attr_perf_event_mux_interval_ms.attr, | |
9101 | NULL, | |
abe43400 | 9102 | }; |
90826ca7 | 9103 | ATTRIBUTE_GROUPS(pmu_dev); |
abe43400 PZ |
9104 | |
9105 | static int pmu_bus_running; | |
9106 | static struct bus_type pmu_bus = { | |
9107 | .name = "event_source", | |
90826ca7 | 9108 | .dev_groups = pmu_dev_groups, |
abe43400 PZ |
9109 | }; |
9110 | ||
9111 | static void pmu_dev_release(struct device *dev) | |
9112 | { | |
9113 | kfree(dev); | |
9114 | } | |
9115 | ||
9116 | static int pmu_dev_alloc(struct pmu *pmu) | |
9117 | { | |
9118 | int ret = -ENOMEM; | |
9119 | ||
9120 | pmu->dev = kzalloc(sizeof(struct device), GFP_KERNEL); | |
9121 | if (!pmu->dev) | |
9122 | goto out; | |
9123 | ||
0c9d42ed | 9124 | pmu->dev->groups = pmu->attr_groups; |
abe43400 PZ |
9125 | device_initialize(pmu->dev); |
9126 | ret = dev_set_name(pmu->dev, "%s", pmu->name); | |
9127 | if (ret) | |
9128 | goto free_dev; | |
9129 | ||
9130 | dev_set_drvdata(pmu->dev, pmu); | |
9131 | pmu->dev->bus = &pmu_bus; | |
9132 | pmu->dev->release = pmu_dev_release; | |
9133 | ret = device_add(pmu->dev); | |
9134 | if (ret) | |
9135 | goto free_dev; | |
9136 | ||
6e855cd4 AS |
9137 | /* For PMUs with address filters, throw in an extra attribute: */ |
9138 | if (pmu->nr_addr_filters) | |
9139 | ret = device_create_file(pmu->dev, &dev_attr_nr_addr_filters); | |
9140 | ||
9141 | if (ret) | |
9142 | goto del_dev; | |
9143 | ||
abe43400 PZ |
9144 | out: |
9145 | return ret; | |
9146 | ||
6e855cd4 AS |
9147 | del_dev: |
9148 | device_del(pmu->dev); | |
9149 | ||
abe43400 PZ |
9150 | free_dev: |
9151 | put_device(pmu->dev); | |
9152 | goto out; | |
9153 | } | |
9154 | ||
547e9fd7 | 9155 | static struct lock_class_key cpuctx_mutex; |
facc4307 | 9156 | static struct lock_class_key cpuctx_lock; |
547e9fd7 | 9157 | |
03d8e80b | 9158 | int perf_pmu_register(struct pmu *pmu, const char *name, int type) |
24f1e32c | 9159 | { |
108b02cf | 9160 | int cpu, ret; |
24f1e32c | 9161 | |
b0a873eb | 9162 | mutex_lock(&pmus_lock); |
33696fc0 PZ |
9163 | ret = -ENOMEM; |
9164 | pmu->pmu_disable_count = alloc_percpu(int); | |
9165 | if (!pmu->pmu_disable_count) | |
9166 | goto unlock; | |
f29ac756 | 9167 | |
2e80a82a PZ |
9168 | pmu->type = -1; |
9169 | if (!name) | |
9170 | goto skip_type; | |
9171 | pmu->name = name; | |
9172 | ||
9173 | if (type < 0) { | |
0e9c3be2 TH |
9174 | type = idr_alloc(&pmu_idr, pmu, PERF_TYPE_MAX, 0, GFP_KERNEL); |
9175 | if (type < 0) { | |
9176 | ret = type; | |
2e80a82a PZ |
9177 | goto free_pdc; |
9178 | } | |
9179 | } | |
9180 | pmu->type = type; | |
9181 | ||
abe43400 PZ |
9182 | if (pmu_bus_running) { |
9183 | ret = pmu_dev_alloc(pmu); | |
9184 | if (ret) | |
9185 | goto free_idr; | |
9186 | } | |
9187 | ||
2e80a82a | 9188 | skip_type: |
26657848 PZ |
9189 | if (pmu->task_ctx_nr == perf_hw_context) { |
9190 | static int hw_context_taken = 0; | |
9191 | ||
5101ef20 MR |
9192 | /* |
9193 | * Other than systems with heterogeneous CPUs, it never makes | |
9194 | * sense for two PMUs to share perf_hw_context. PMUs which are | |
9195 | * uncore must use perf_invalid_context. | |
9196 | */ | |
9197 | if (WARN_ON_ONCE(hw_context_taken && | |
9198 | !(pmu->capabilities & PERF_PMU_CAP_HETEROGENEOUS_CPUS))) | |
26657848 PZ |
9199 | pmu->task_ctx_nr = perf_invalid_context; |
9200 | ||
9201 | hw_context_taken = 1; | |
9202 | } | |
9203 | ||
8dc85d54 PZ |
9204 | pmu->pmu_cpu_context = find_pmu_context(pmu->task_ctx_nr); |
9205 | if (pmu->pmu_cpu_context) | |
9206 | goto got_cpu_context; | |
f29ac756 | 9207 | |
c4814202 | 9208 | ret = -ENOMEM; |
108b02cf PZ |
9209 | pmu->pmu_cpu_context = alloc_percpu(struct perf_cpu_context); |
9210 | if (!pmu->pmu_cpu_context) | |
abe43400 | 9211 | goto free_dev; |
f344011c | 9212 | |
108b02cf PZ |
9213 | for_each_possible_cpu(cpu) { |
9214 | struct perf_cpu_context *cpuctx; | |
9215 | ||
9216 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
eb184479 | 9217 | __perf_event_init_context(&cpuctx->ctx); |
547e9fd7 | 9218 | lockdep_set_class(&cpuctx->ctx.mutex, &cpuctx_mutex); |
facc4307 | 9219 | lockdep_set_class(&cpuctx->ctx.lock, &cpuctx_lock); |
108b02cf | 9220 | cpuctx->ctx.pmu = pmu; |
a63fbed7 | 9221 | cpuctx->online = cpumask_test_cpu(cpu, perf_online_mask); |
9e630205 | 9222 | |
272325c4 | 9223 | __perf_mux_hrtimer_init(cpuctx, cpu); |
108b02cf | 9224 | } |
76e1d904 | 9225 | |
8dc85d54 | 9226 | got_cpu_context: |
ad5133b7 PZ |
9227 | if (!pmu->start_txn) { |
9228 | if (pmu->pmu_enable) { | |
9229 | /* | |
9230 | * If we have pmu_enable/pmu_disable calls, install | |
9231 | * transaction stubs that use that to try and batch | |
9232 | * hardware accesses. | |
9233 | */ | |
9234 | pmu->start_txn = perf_pmu_start_txn; | |
9235 | pmu->commit_txn = perf_pmu_commit_txn; | |
9236 | pmu->cancel_txn = perf_pmu_cancel_txn; | |
9237 | } else { | |
fbbe0701 | 9238 | pmu->start_txn = perf_pmu_nop_txn; |
ad5133b7 PZ |
9239 | pmu->commit_txn = perf_pmu_nop_int; |
9240 | pmu->cancel_txn = perf_pmu_nop_void; | |
f344011c | 9241 | } |
5c92d124 | 9242 | } |
15dbf27c | 9243 | |
ad5133b7 PZ |
9244 | if (!pmu->pmu_enable) { |
9245 | pmu->pmu_enable = perf_pmu_nop_void; | |
9246 | pmu->pmu_disable = perf_pmu_nop_void; | |
9247 | } | |
9248 | ||
57f9f919 JO |
9249 | if (!pmu->check_period) |
9250 | pmu->check_period = perf_event_nop_int; | |
9251 | ||
35edc2a5 PZ |
9252 | if (!pmu->event_idx) |
9253 | pmu->event_idx = perf_event_idx_default; | |
9254 | ||
b0a873eb | 9255 | list_add_rcu(&pmu->entry, &pmus); |
bed5b25a | 9256 | atomic_set(&pmu->exclusive_cnt, 0); |
33696fc0 PZ |
9257 | ret = 0; |
9258 | unlock: | |
b0a873eb PZ |
9259 | mutex_unlock(&pmus_lock); |
9260 | ||
33696fc0 | 9261 | return ret; |
108b02cf | 9262 | |
abe43400 PZ |
9263 | free_dev: |
9264 | device_del(pmu->dev); | |
9265 | put_device(pmu->dev); | |
9266 | ||
2e80a82a PZ |
9267 | free_idr: |
9268 | if (pmu->type >= PERF_TYPE_MAX) | |
9269 | idr_remove(&pmu_idr, pmu->type); | |
9270 | ||
108b02cf PZ |
9271 | free_pdc: |
9272 | free_percpu(pmu->pmu_disable_count); | |
9273 | goto unlock; | |
f29ac756 | 9274 | } |
c464c76e | 9275 | EXPORT_SYMBOL_GPL(perf_pmu_register); |
f29ac756 | 9276 | |
b0a873eb | 9277 | void perf_pmu_unregister(struct pmu *pmu) |
5c92d124 | 9278 | { |
b0a873eb PZ |
9279 | mutex_lock(&pmus_lock); |
9280 | list_del_rcu(&pmu->entry); | |
5c92d124 | 9281 | |
0475f9ea | 9282 | /* |
cde8e884 PZ |
9283 | * We dereference the pmu list under both SRCU and regular RCU, so |
9284 | * synchronize against both of those. | |
0475f9ea | 9285 | */ |
b0a873eb | 9286 | synchronize_srcu(&pmus_srcu); |
cde8e884 | 9287 | synchronize_rcu(); |
d6d020e9 | 9288 | |
33696fc0 | 9289 | free_percpu(pmu->pmu_disable_count); |
2e80a82a PZ |
9290 | if (pmu->type >= PERF_TYPE_MAX) |
9291 | idr_remove(&pmu_idr, pmu->type); | |
9db14710 | 9292 | if (pmu_bus_running) { |
0933840a JO |
9293 | if (pmu->nr_addr_filters) |
9294 | device_remove_file(pmu->dev, &dev_attr_nr_addr_filters); | |
9295 | device_del(pmu->dev); | |
9296 | put_device(pmu->dev); | |
9297 | } | |
51676957 | 9298 | free_pmu_context(pmu); |
9db14710 | 9299 | mutex_unlock(&pmus_lock); |
b0a873eb | 9300 | } |
c464c76e | 9301 | EXPORT_SYMBOL_GPL(perf_pmu_unregister); |
d6d020e9 | 9302 | |
cc34b98b MR |
9303 | static int perf_try_init_event(struct pmu *pmu, struct perf_event *event) |
9304 | { | |
ccd41c86 | 9305 | struct perf_event_context *ctx = NULL; |
cc34b98b MR |
9306 | int ret; |
9307 | ||
9308 | if (!try_module_get(pmu->module)) | |
9309 | return -ENODEV; | |
ccd41c86 | 9310 | |
0c7296ca PZ |
9311 | /* |
9312 | * A number of pmu->event_init() methods iterate the sibling_list to, | |
9313 | * for example, validate if the group fits on the PMU. Therefore, | |
9314 | * if this is a sibling event, acquire the ctx->mutex to protect | |
9315 | * the sibling_list. | |
9316 | */ | |
9317 | if (event->group_leader != event && pmu->task_ctx_nr != perf_sw_context) { | |
8b10c5e2 PZ |
9318 | /* |
9319 | * This ctx->mutex can nest when we're called through | |
9320 | * inheritance. See the perf_event_ctx_lock_nested() comment. | |
9321 | */ | |
9322 | ctx = perf_event_ctx_lock_nested(event->group_leader, | |
9323 | SINGLE_DEPTH_NESTING); | |
ccd41c86 PZ |
9324 | BUG_ON(!ctx); |
9325 | } | |
9326 | ||
cc34b98b MR |
9327 | event->pmu = pmu; |
9328 | ret = pmu->event_init(event); | |
ccd41c86 PZ |
9329 | |
9330 | if (ctx) | |
9331 | perf_event_ctx_unlock(event->group_leader, ctx); | |
9332 | ||
cc34b98b MR |
9333 | if (ret) |
9334 | module_put(pmu->module); | |
9335 | ||
9336 | return ret; | |
9337 | } | |
9338 | ||
18ab2cd3 | 9339 | static struct pmu *perf_init_event(struct perf_event *event) |
b0a873eb | 9340 | { |
85c617ab | 9341 | struct pmu *pmu; |
b0a873eb | 9342 | int idx; |
940c5b29 | 9343 | int ret; |
b0a873eb PZ |
9344 | |
9345 | idx = srcu_read_lock(&pmus_srcu); | |
2e80a82a | 9346 | |
40999312 KL |
9347 | /* Try parent's PMU first: */ |
9348 | if (event->parent && event->parent->pmu) { | |
9349 | pmu = event->parent->pmu; | |
9350 | ret = perf_try_init_event(pmu, event); | |
9351 | if (!ret) | |
9352 | goto unlock; | |
9353 | } | |
9354 | ||
2e80a82a PZ |
9355 | rcu_read_lock(); |
9356 | pmu = idr_find(&pmu_idr, event->attr.type); | |
9357 | rcu_read_unlock(); | |
940c5b29 | 9358 | if (pmu) { |
cc34b98b | 9359 | ret = perf_try_init_event(pmu, event); |
940c5b29 LM |
9360 | if (ret) |
9361 | pmu = ERR_PTR(ret); | |
2e80a82a | 9362 | goto unlock; |
940c5b29 | 9363 | } |
2e80a82a | 9364 | |
b0a873eb | 9365 | list_for_each_entry_rcu(pmu, &pmus, entry) { |
cc34b98b | 9366 | ret = perf_try_init_event(pmu, event); |
b0a873eb | 9367 | if (!ret) |
e5f4d339 | 9368 | goto unlock; |
76e1d904 | 9369 | |
b0a873eb PZ |
9370 | if (ret != -ENOENT) { |
9371 | pmu = ERR_PTR(ret); | |
e5f4d339 | 9372 | goto unlock; |
f344011c | 9373 | } |
5c92d124 | 9374 | } |
e5f4d339 PZ |
9375 | pmu = ERR_PTR(-ENOENT); |
9376 | unlock: | |
b0a873eb | 9377 | srcu_read_unlock(&pmus_srcu, idx); |
15dbf27c | 9378 | |
4aeb0b42 | 9379 | return pmu; |
5c92d124 IM |
9380 | } |
9381 | ||
f2fb6bef KL |
9382 | static void attach_sb_event(struct perf_event *event) |
9383 | { | |
9384 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
9385 | ||
9386 | raw_spin_lock(&pel->lock); | |
9387 | list_add_rcu(&event->sb_list, &pel->list); | |
9388 | raw_spin_unlock(&pel->lock); | |
9389 | } | |
9390 | ||
aab5b71e PZ |
9391 | /* |
9392 | * We keep a list of all !task (and therefore per-cpu) events | |
9393 | * that need to receive side-band records. | |
9394 | * | |
9395 | * This avoids having to scan all the various PMU per-cpu contexts | |
9396 | * looking for them. | |
9397 | */ | |
f2fb6bef KL |
9398 | static void account_pmu_sb_event(struct perf_event *event) |
9399 | { | |
a4f144eb | 9400 | if (is_sb_event(event)) |
f2fb6bef KL |
9401 | attach_sb_event(event); |
9402 | } | |
9403 | ||
4beb31f3 FW |
9404 | static void account_event_cpu(struct perf_event *event, int cpu) |
9405 | { | |
9406 | if (event->parent) | |
9407 | return; | |
9408 | ||
4beb31f3 FW |
9409 | if (is_cgroup_event(event)) |
9410 | atomic_inc(&per_cpu(perf_cgroup_events, cpu)); | |
9411 | } | |
9412 | ||
555e0c1e FW |
9413 | /* Freq events need the tick to stay alive (see perf_event_task_tick). */ |
9414 | static void account_freq_event_nohz(void) | |
9415 | { | |
9416 | #ifdef CONFIG_NO_HZ_FULL | |
9417 | /* Lock so we don't race with concurrent unaccount */ | |
9418 | spin_lock(&nr_freq_lock); | |
9419 | if (atomic_inc_return(&nr_freq_events) == 1) | |
9420 | tick_nohz_dep_set(TICK_DEP_BIT_PERF_EVENTS); | |
9421 | spin_unlock(&nr_freq_lock); | |
9422 | #endif | |
9423 | } | |
9424 | ||
9425 | static void account_freq_event(void) | |
9426 | { | |
9427 | if (tick_nohz_full_enabled()) | |
9428 | account_freq_event_nohz(); | |
9429 | else | |
9430 | atomic_inc(&nr_freq_events); | |
9431 | } | |
9432 | ||
9433 | ||
766d6c07 FW |
9434 | static void account_event(struct perf_event *event) |
9435 | { | |
25432ae9 PZ |
9436 | bool inc = false; |
9437 | ||
4beb31f3 FW |
9438 | if (event->parent) |
9439 | return; | |
9440 | ||
766d6c07 | 9441 | if (event->attach_state & PERF_ATTACH_TASK) |
25432ae9 | 9442 | inc = true; |
766d6c07 FW |
9443 | if (event->attr.mmap || event->attr.mmap_data) |
9444 | atomic_inc(&nr_mmap_events); | |
9445 | if (event->attr.comm) | |
9446 | atomic_inc(&nr_comm_events); | |
e4222673 HB |
9447 | if (event->attr.namespaces) |
9448 | atomic_inc(&nr_namespaces_events); | |
766d6c07 FW |
9449 | if (event->attr.task) |
9450 | atomic_inc(&nr_task_events); | |
555e0c1e FW |
9451 | if (event->attr.freq) |
9452 | account_freq_event(); | |
45ac1403 AH |
9453 | if (event->attr.context_switch) { |
9454 | atomic_inc(&nr_switch_events); | |
25432ae9 | 9455 | inc = true; |
45ac1403 | 9456 | } |
4beb31f3 | 9457 | if (has_branch_stack(event)) |
25432ae9 | 9458 | inc = true; |
4beb31f3 | 9459 | if (is_cgroup_event(event)) |
25432ae9 PZ |
9460 | inc = true; |
9461 | ||
9107c89e | 9462 | if (inc) { |
5bce9db1 AS |
9463 | /* |
9464 | * We need the mutex here because static_branch_enable() | |
9465 | * must complete *before* the perf_sched_count increment | |
9466 | * becomes visible. | |
9467 | */ | |
9107c89e PZ |
9468 | if (atomic_inc_not_zero(&perf_sched_count)) |
9469 | goto enabled; | |
9470 | ||
9471 | mutex_lock(&perf_sched_mutex); | |
9472 | if (!atomic_read(&perf_sched_count)) { | |
9473 | static_branch_enable(&perf_sched_events); | |
9474 | /* | |
9475 | * Guarantee that all CPUs observe they key change and | |
9476 | * call the perf scheduling hooks before proceeding to | |
9477 | * install events that need them. | |
9478 | */ | |
9479 | synchronize_sched(); | |
9480 | } | |
9481 | /* | |
9482 | * Now that we have waited for the sync_sched(), allow further | |
9483 | * increments to by-pass the mutex. | |
9484 | */ | |
9485 | atomic_inc(&perf_sched_count); | |
9486 | mutex_unlock(&perf_sched_mutex); | |
9487 | } | |
9488 | enabled: | |
4beb31f3 FW |
9489 | |
9490 | account_event_cpu(event, event->cpu); | |
f2fb6bef KL |
9491 | |
9492 | account_pmu_sb_event(event); | |
766d6c07 FW |
9493 | } |
9494 | ||
0793a61d | 9495 | /* |
cdd6c482 | 9496 | * Allocate and initialize a event structure |
0793a61d | 9497 | */ |
cdd6c482 | 9498 | static struct perf_event * |
c3f00c70 | 9499 | perf_event_alloc(struct perf_event_attr *attr, int cpu, |
d580ff86 PZ |
9500 | struct task_struct *task, |
9501 | struct perf_event *group_leader, | |
9502 | struct perf_event *parent_event, | |
4dc0da86 | 9503 | perf_overflow_handler_t overflow_handler, |
79dff51e | 9504 | void *context, int cgroup_fd) |
0793a61d | 9505 | { |
51b0fe39 | 9506 | struct pmu *pmu; |
cdd6c482 IM |
9507 | struct perf_event *event; |
9508 | struct hw_perf_event *hwc; | |
90983b16 | 9509 | long err = -EINVAL; |
0793a61d | 9510 | |
66832eb4 ON |
9511 | if ((unsigned)cpu >= nr_cpu_ids) { |
9512 | if (!task || cpu != -1) | |
9513 | return ERR_PTR(-EINVAL); | |
9514 | } | |
9515 | ||
c3f00c70 | 9516 | event = kzalloc(sizeof(*event), GFP_KERNEL); |
cdd6c482 | 9517 | if (!event) |
d5d2bc0d | 9518 | return ERR_PTR(-ENOMEM); |
0793a61d | 9519 | |
04289bb9 | 9520 | /* |
cdd6c482 | 9521 | * Single events are their own group leaders, with an |
04289bb9 IM |
9522 | * empty sibling list: |
9523 | */ | |
9524 | if (!group_leader) | |
cdd6c482 | 9525 | group_leader = event; |
04289bb9 | 9526 | |
cdd6c482 IM |
9527 | mutex_init(&event->child_mutex); |
9528 | INIT_LIST_HEAD(&event->child_list); | |
fccc714b | 9529 | |
cdd6c482 IM |
9530 | INIT_LIST_HEAD(&event->group_entry); |
9531 | INIT_LIST_HEAD(&event->event_entry); | |
9532 | INIT_LIST_HEAD(&event->sibling_list); | |
10c6db11 | 9533 | INIT_LIST_HEAD(&event->rb_entry); |
71ad88ef | 9534 | INIT_LIST_HEAD(&event->active_entry); |
375637bc | 9535 | INIT_LIST_HEAD(&event->addr_filters.list); |
f3ae75de SE |
9536 | INIT_HLIST_NODE(&event->hlist_entry); |
9537 | ||
10c6db11 | 9538 | |
cdd6c482 | 9539 | init_waitqueue_head(&event->waitq); |
ac69b885 | 9540 | event->pending_disable = -1; |
e360adbe | 9541 | init_irq_work(&event->pending, perf_pending_event); |
0793a61d | 9542 | |
cdd6c482 | 9543 | mutex_init(&event->mmap_mutex); |
375637bc | 9544 | raw_spin_lock_init(&event->addr_filters.lock); |
7b732a75 | 9545 | |
a6fa941d | 9546 | atomic_long_set(&event->refcount, 1); |
cdd6c482 IM |
9547 | event->cpu = cpu; |
9548 | event->attr = *attr; | |
9549 | event->group_leader = group_leader; | |
9550 | event->pmu = NULL; | |
cdd6c482 | 9551 | event->oncpu = -1; |
a96bbc16 | 9552 | |
cdd6c482 | 9553 | event->parent = parent_event; |
b84fbc9f | 9554 | |
17cf22c3 | 9555 | event->ns = get_pid_ns(task_active_pid_ns(current)); |
cdd6c482 | 9556 | event->id = atomic64_inc_return(&perf_event_id); |
a96bbc16 | 9557 | |
cdd6c482 | 9558 | event->state = PERF_EVENT_STATE_INACTIVE; |
329d876d | 9559 | |
d580ff86 PZ |
9560 | if (task) { |
9561 | event->attach_state = PERF_ATTACH_TASK; | |
d580ff86 | 9562 | /* |
50f16a8b PZ |
9563 | * XXX pmu::event_init needs to know what task to account to |
9564 | * and we cannot use the ctx information because we need the | |
9565 | * pmu before we get a ctx. | |
d580ff86 | 9566 | */ |
ae162419 | 9567 | get_task_struct(task); |
50f16a8b | 9568 | event->hw.target = task; |
d580ff86 PZ |
9569 | } |
9570 | ||
34f43927 PZ |
9571 | event->clock = &local_clock; |
9572 | if (parent_event) | |
9573 | event->clock = parent_event->clock; | |
9574 | ||
4dc0da86 | 9575 | if (!overflow_handler && parent_event) { |
b326e956 | 9576 | overflow_handler = parent_event->overflow_handler; |
4dc0da86 | 9577 | context = parent_event->overflow_handler_context; |
f1e4ba5b | 9578 | #if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_EVENT_TRACING) |
aa6a5f3c AS |
9579 | if (overflow_handler == bpf_overflow_handler) { |
9580 | struct bpf_prog *prog = bpf_prog_inc(parent_event->prog); | |
9581 | ||
9582 | if (IS_ERR(prog)) { | |
9583 | err = PTR_ERR(prog); | |
9584 | goto err_ns; | |
9585 | } | |
9586 | event->prog = prog; | |
9587 | event->orig_overflow_handler = | |
9588 | parent_event->orig_overflow_handler; | |
9589 | } | |
9590 | #endif | |
4dc0da86 | 9591 | } |
66832eb4 | 9592 | |
1879445d WN |
9593 | if (overflow_handler) { |
9594 | event->overflow_handler = overflow_handler; | |
9595 | event->overflow_handler_context = context; | |
9ecda41a WN |
9596 | } else if (is_write_backward(event)){ |
9597 | event->overflow_handler = perf_event_output_backward; | |
9598 | event->overflow_handler_context = NULL; | |
1879445d | 9599 | } else { |
9ecda41a | 9600 | event->overflow_handler = perf_event_output_forward; |
1879445d WN |
9601 | event->overflow_handler_context = NULL; |
9602 | } | |
97eaf530 | 9603 | |
0231bb53 | 9604 | perf_event__state_init(event); |
a86ed508 | 9605 | |
4aeb0b42 | 9606 | pmu = NULL; |
b8e83514 | 9607 | |
cdd6c482 | 9608 | hwc = &event->hw; |
bd2b5b12 | 9609 | hwc->sample_period = attr->sample_period; |
0d48696f | 9610 | if (attr->freq && attr->sample_freq) |
bd2b5b12 | 9611 | hwc->sample_period = 1; |
eced1dfc | 9612 | hwc->last_period = hwc->sample_period; |
bd2b5b12 | 9613 | |
e7850595 | 9614 | local64_set(&hwc->period_left, hwc->sample_period); |
60db5e09 | 9615 | |
2023b359 | 9616 | /* |
ba5213ae PZ |
9617 | * We currently do not support PERF_SAMPLE_READ on inherited events. |
9618 | * See perf_output_read(). | |
2023b359 | 9619 | */ |
ba5213ae | 9620 | if (attr->inherit && (attr->sample_type & PERF_SAMPLE_READ)) |
90983b16 | 9621 | goto err_ns; |
a46a2300 YZ |
9622 | |
9623 | if (!has_branch_stack(event)) | |
9624 | event->attr.branch_sample_type = 0; | |
2023b359 | 9625 | |
79dff51e MF |
9626 | if (cgroup_fd != -1) { |
9627 | err = perf_cgroup_connect(cgroup_fd, event, attr, group_leader); | |
9628 | if (err) | |
9629 | goto err_ns; | |
9630 | } | |
9631 | ||
b0a873eb | 9632 | pmu = perf_init_event(event); |
85c617ab | 9633 | if (IS_ERR(pmu)) { |
4aeb0b42 | 9634 | err = PTR_ERR(pmu); |
90983b16 | 9635 | goto err_ns; |
621a01ea | 9636 | } |
d5d2bc0d | 9637 | |
bed5b25a AS |
9638 | err = exclusive_event_init(event); |
9639 | if (err) | |
9640 | goto err_pmu; | |
9641 | ||
375637bc AS |
9642 | if (has_addr_filter(event)) { |
9643 | event->addr_filters_offs = kcalloc(pmu->nr_addr_filters, | |
9644 | sizeof(unsigned long), | |
9645 | GFP_KERNEL); | |
36cc2b92 DC |
9646 | if (!event->addr_filters_offs) { |
9647 | err = -ENOMEM; | |
375637bc | 9648 | goto err_per_task; |
36cc2b92 | 9649 | } |
375637bc | 9650 | |
d2f9c5e7 AS |
9651 | /* |
9652 | * Clone the parent's vma offsets: they are valid until exec() | |
9653 | * even if the mm is not shared with the parent. | |
9654 | */ | |
9655 | if (event->parent) { | |
9656 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
9657 | ||
9658 | raw_spin_lock_irq(&ifh->lock); | |
9659 | memcpy(event->addr_filters_offs, | |
9660 | event->parent->addr_filters_offs, | |
9661 | pmu->nr_addr_filters * sizeof(unsigned long)); | |
9662 | raw_spin_unlock_irq(&ifh->lock); | |
9663 | } | |
9664 | ||
375637bc AS |
9665 | /* force hw sync on the address filters */ |
9666 | event->addr_filters_gen = 1; | |
9667 | } | |
9668 | ||
cdd6c482 | 9669 | if (!event->parent) { |
927c7a9e | 9670 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) { |
97c79a38 | 9671 | err = get_callchain_buffers(attr->sample_max_stack); |
90983b16 | 9672 | if (err) |
375637bc | 9673 | goto err_addr_filters; |
d010b332 | 9674 | } |
f344011c | 9675 | } |
9ee318a7 | 9676 | |
927a5570 AS |
9677 | /* symmetric to unaccount_event() in _free_event() */ |
9678 | account_event(event); | |
9679 | ||
cdd6c482 | 9680 | return event; |
90983b16 | 9681 | |
375637bc AS |
9682 | err_addr_filters: |
9683 | kfree(event->addr_filters_offs); | |
9684 | ||
bed5b25a AS |
9685 | err_per_task: |
9686 | exclusive_event_destroy(event); | |
9687 | ||
90983b16 FW |
9688 | err_pmu: |
9689 | if (event->destroy) | |
9690 | event->destroy(event); | |
c464c76e | 9691 | module_put(pmu->module); |
90983b16 | 9692 | err_ns: |
79dff51e MF |
9693 | if (is_cgroup_event(event)) |
9694 | perf_detach_cgroup(event); | |
90983b16 FW |
9695 | if (event->ns) |
9696 | put_pid_ns(event->ns); | |
ae162419 PB |
9697 | if (event->hw.target) |
9698 | put_task_struct(event->hw.target); | |
90983b16 FW |
9699 | kfree(event); |
9700 | ||
9701 | return ERR_PTR(err); | |
0793a61d TG |
9702 | } |
9703 | ||
cdd6c482 IM |
9704 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
9705 | struct perf_event_attr *attr) | |
974802ea | 9706 | { |
974802ea | 9707 | u32 size; |
cdf8073d | 9708 | int ret; |
974802ea PZ |
9709 | |
9710 | if (!access_ok(VERIFY_WRITE, uattr, PERF_ATTR_SIZE_VER0)) | |
9711 | return -EFAULT; | |
9712 | ||
9713 | /* | |
9714 | * zero the full structure, so that a short copy will be nice. | |
9715 | */ | |
9716 | memset(attr, 0, sizeof(*attr)); | |
9717 | ||
9718 | ret = get_user(size, &uattr->size); | |
9719 | if (ret) | |
9720 | return ret; | |
9721 | ||
9722 | if (size > PAGE_SIZE) /* silly large */ | |
9723 | goto err_size; | |
9724 | ||
9725 | if (!size) /* abi compat */ | |
9726 | size = PERF_ATTR_SIZE_VER0; | |
9727 | ||
9728 | if (size < PERF_ATTR_SIZE_VER0) | |
9729 | goto err_size; | |
9730 | ||
9731 | /* | |
9732 | * If we're handed a bigger struct than we know of, | |
cdf8073d IS |
9733 | * ensure all the unknown bits are 0 - i.e. new |
9734 | * user-space does not rely on any kernel feature | |
9735 | * extensions we dont know about yet. | |
974802ea PZ |
9736 | */ |
9737 | if (size > sizeof(*attr)) { | |
cdf8073d IS |
9738 | unsigned char __user *addr; |
9739 | unsigned char __user *end; | |
9740 | unsigned char val; | |
974802ea | 9741 | |
cdf8073d IS |
9742 | addr = (void __user *)uattr + sizeof(*attr); |
9743 | end = (void __user *)uattr + size; | |
974802ea | 9744 | |
cdf8073d | 9745 | for (; addr < end; addr++) { |
974802ea PZ |
9746 | ret = get_user(val, addr); |
9747 | if (ret) | |
9748 | return ret; | |
9749 | if (val) | |
9750 | goto err_size; | |
9751 | } | |
b3e62e35 | 9752 | size = sizeof(*attr); |
974802ea PZ |
9753 | } |
9754 | ||
9755 | ret = copy_from_user(attr, uattr, size); | |
9756 | if (ret) | |
9757 | return -EFAULT; | |
9758 | ||
f12f42ac MX |
9759 | attr->size = size; |
9760 | ||
cd757645 | 9761 | if (attr->__reserved_1) |
974802ea PZ |
9762 | return -EINVAL; |
9763 | ||
9764 | if (attr->sample_type & ~(PERF_SAMPLE_MAX-1)) | |
9765 | return -EINVAL; | |
9766 | ||
9767 | if (attr->read_format & ~(PERF_FORMAT_MAX-1)) | |
9768 | return -EINVAL; | |
9769 | ||
bce38cd5 SE |
9770 | if (attr->sample_type & PERF_SAMPLE_BRANCH_STACK) { |
9771 | u64 mask = attr->branch_sample_type; | |
9772 | ||
9773 | /* only using defined bits */ | |
9774 | if (mask & ~(PERF_SAMPLE_BRANCH_MAX-1)) | |
9775 | return -EINVAL; | |
9776 | ||
9777 | /* at least one branch bit must be set */ | |
9778 | if (!(mask & ~PERF_SAMPLE_BRANCH_PLM_ALL)) | |
9779 | return -EINVAL; | |
9780 | ||
bce38cd5 SE |
9781 | /* propagate priv level, when not set for branch */ |
9782 | if (!(mask & PERF_SAMPLE_BRANCH_PLM_ALL)) { | |
9783 | ||
9784 | /* exclude_kernel checked on syscall entry */ | |
9785 | if (!attr->exclude_kernel) | |
9786 | mask |= PERF_SAMPLE_BRANCH_KERNEL; | |
9787 | ||
9788 | if (!attr->exclude_user) | |
9789 | mask |= PERF_SAMPLE_BRANCH_USER; | |
9790 | ||
9791 | if (!attr->exclude_hv) | |
9792 | mask |= PERF_SAMPLE_BRANCH_HV; | |
9793 | /* | |
9794 | * adjust user setting (for HW filter setup) | |
9795 | */ | |
9796 | attr->branch_sample_type = mask; | |
9797 | } | |
e712209a SE |
9798 | /* privileged levels capture (kernel, hv): check permissions */ |
9799 | if ((mask & PERF_SAMPLE_BRANCH_PERM_PLM) | |
2b923c8f SE |
9800 | && perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) |
9801 | return -EACCES; | |
bce38cd5 | 9802 | } |
4018994f | 9803 | |
c5ebcedb | 9804 | if (attr->sample_type & PERF_SAMPLE_REGS_USER) { |
4018994f | 9805 | ret = perf_reg_validate(attr->sample_regs_user); |
c5ebcedb JO |
9806 | if (ret) |
9807 | return ret; | |
9808 | } | |
9809 | ||
9810 | if (attr->sample_type & PERF_SAMPLE_STACK_USER) { | |
9811 | if (!arch_perf_have_user_stack_dump()) | |
9812 | return -ENOSYS; | |
9813 | ||
9814 | /* | |
9815 | * We have __u32 type for the size, but so far | |
9816 | * we can only use __u16 as maximum due to the | |
9817 | * __u16 sample size limit. | |
9818 | */ | |
9819 | if (attr->sample_stack_user >= USHRT_MAX) | |
0b105afa | 9820 | return -EINVAL; |
c5ebcedb | 9821 | else if (!IS_ALIGNED(attr->sample_stack_user, sizeof(u64))) |
0b105afa | 9822 | return -EINVAL; |
c5ebcedb | 9823 | } |
4018994f | 9824 | |
60e2364e SE |
9825 | if (attr->sample_type & PERF_SAMPLE_REGS_INTR) |
9826 | ret = perf_reg_validate(attr->sample_regs_intr); | |
974802ea PZ |
9827 | out: |
9828 | return ret; | |
9829 | ||
9830 | err_size: | |
9831 | put_user(sizeof(*attr), &uattr->size); | |
9832 | ret = -E2BIG; | |
9833 | goto out; | |
9834 | } | |
9835 | ||
ac9721f3 PZ |
9836 | static int |
9837 | perf_event_set_output(struct perf_event *event, struct perf_event *output_event) | |
a4be7c27 | 9838 | { |
b69cf536 | 9839 | struct ring_buffer *rb = NULL; |
a4be7c27 PZ |
9840 | int ret = -EINVAL; |
9841 | ||
ac9721f3 | 9842 | if (!output_event) |
a4be7c27 PZ |
9843 | goto set; |
9844 | ||
ac9721f3 PZ |
9845 | /* don't allow circular references */ |
9846 | if (event == output_event) | |
a4be7c27 PZ |
9847 | goto out; |
9848 | ||
0f139300 PZ |
9849 | /* |
9850 | * Don't allow cross-cpu buffers | |
9851 | */ | |
9852 | if (output_event->cpu != event->cpu) | |
9853 | goto out; | |
9854 | ||
9855 | /* | |
76369139 | 9856 | * If its not a per-cpu rb, it must be the same task. |
0f139300 PZ |
9857 | */ |
9858 | if (output_event->cpu == -1 && output_event->ctx != event->ctx) | |
9859 | goto out; | |
9860 | ||
34f43927 PZ |
9861 | /* |
9862 | * Mixing clocks in the same buffer is trouble you don't need. | |
9863 | */ | |
9864 | if (output_event->clock != event->clock) | |
9865 | goto out; | |
9866 | ||
9ecda41a WN |
9867 | /* |
9868 | * Either writing ring buffer from beginning or from end. | |
9869 | * Mixing is not allowed. | |
9870 | */ | |
9871 | if (is_write_backward(output_event) != is_write_backward(event)) | |
9872 | goto out; | |
9873 | ||
45bfb2e5 PZ |
9874 | /* |
9875 | * If both events generate aux data, they must be on the same PMU | |
9876 | */ | |
9877 | if (has_aux(event) && has_aux(output_event) && | |
9878 | event->pmu != output_event->pmu) | |
9879 | goto out; | |
9880 | ||
a4be7c27 | 9881 | set: |
cdd6c482 | 9882 | mutex_lock(&event->mmap_mutex); |
ac9721f3 PZ |
9883 | /* Can't redirect output if we've got an active mmap() */ |
9884 | if (atomic_read(&event->mmap_count)) | |
9885 | goto unlock; | |
a4be7c27 | 9886 | |
ac9721f3 | 9887 | if (output_event) { |
76369139 FW |
9888 | /* get the rb we want to redirect to */ |
9889 | rb = ring_buffer_get(output_event); | |
9890 | if (!rb) | |
ac9721f3 | 9891 | goto unlock; |
a4be7c27 PZ |
9892 | } |
9893 | ||
b69cf536 | 9894 | ring_buffer_attach(event, rb); |
9bb5d40c | 9895 | |
a4be7c27 | 9896 | ret = 0; |
ac9721f3 PZ |
9897 | unlock: |
9898 | mutex_unlock(&event->mmap_mutex); | |
9899 | ||
a4be7c27 | 9900 | out: |
a4be7c27 PZ |
9901 | return ret; |
9902 | } | |
9903 | ||
f63a8daa PZ |
9904 | static void mutex_lock_double(struct mutex *a, struct mutex *b) |
9905 | { | |
9906 | if (b < a) | |
9907 | swap(a, b); | |
9908 | ||
9909 | mutex_lock(a); | |
9910 | mutex_lock_nested(b, SINGLE_DEPTH_NESTING); | |
9911 | } | |
9912 | ||
34f43927 PZ |
9913 | static int perf_event_set_clock(struct perf_event *event, clockid_t clk_id) |
9914 | { | |
9915 | bool nmi_safe = false; | |
9916 | ||
9917 | switch (clk_id) { | |
9918 | case CLOCK_MONOTONIC: | |
9919 | event->clock = &ktime_get_mono_fast_ns; | |
9920 | nmi_safe = true; | |
9921 | break; | |
9922 | ||
9923 | case CLOCK_MONOTONIC_RAW: | |
9924 | event->clock = &ktime_get_raw_fast_ns; | |
9925 | nmi_safe = true; | |
9926 | break; | |
9927 | ||
9928 | case CLOCK_REALTIME: | |
9929 | event->clock = &ktime_get_real_ns; | |
9930 | break; | |
9931 | ||
9932 | case CLOCK_BOOTTIME: | |
9933 | event->clock = &ktime_get_boot_ns; | |
9934 | break; | |
9935 | ||
9936 | case CLOCK_TAI: | |
9937 | event->clock = &ktime_get_tai_ns; | |
9938 | break; | |
9939 | ||
9940 | default: | |
9941 | return -EINVAL; | |
9942 | } | |
9943 | ||
9944 | if (!nmi_safe && !(event->pmu->capabilities & PERF_PMU_CAP_NO_NMI)) | |
9945 | return -EINVAL; | |
9946 | ||
9947 | return 0; | |
9948 | } | |
9949 | ||
321027c1 PZ |
9950 | /* |
9951 | * Variation on perf_event_ctx_lock_nested(), except we take two context | |
9952 | * mutexes. | |
9953 | */ | |
9954 | static struct perf_event_context * | |
9955 | __perf_event_ctx_lock_double(struct perf_event *group_leader, | |
9956 | struct perf_event_context *ctx) | |
9957 | { | |
9958 | struct perf_event_context *gctx; | |
9959 | ||
9960 | again: | |
9961 | rcu_read_lock(); | |
9962 | gctx = READ_ONCE(group_leader->ctx); | |
9963 | if (!atomic_inc_not_zero(&gctx->refcount)) { | |
9964 | rcu_read_unlock(); | |
9965 | goto again; | |
9966 | } | |
9967 | rcu_read_unlock(); | |
9968 | ||
9969 | mutex_lock_double(&gctx->mutex, &ctx->mutex); | |
9970 | ||
9971 | if (group_leader->ctx != gctx) { | |
9972 | mutex_unlock(&ctx->mutex); | |
9973 | mutex_unlock(&gctx->mutex); | |
9974 | put_ctx(gctx); | |
9975 | goto again; | |
9976 | } | |
9977 | ||
9978 | return gctx; | |
9979 | } | |
9980 | ||
0793a61d | 9981 | /** |
cdd6c482 | 9982 | * sys_perf_event_open - open a performance event, associate it to a task/cpu |
9f66a381 | 9983 | * |
cdd6c482 | 9984 | * @attr_uptr: event_id type attributes for monitoring/sampling |
0793a61d | 9985 | * @pid: target pid |
9f66a381 | 9986 | * @cpu: target cpu |
cdd6c482 | 9987 | * @group_fd: group leader event fd |
0793a61d | 9988 | */ |
cdd6c482 IM |
9989 | SYSCALL_DEFINE5(perf_event_open, |
9990 | struct perf_event_attr __user *, attr_uptr, | |
2743a5b0 | 9991 | pid_t, pid, int, cpu, int, group_fd, unsigned long, flags) |
0793a61d | 9992 | { |
b04243ef PZ |
9993 | struct perf_event *group_leader = NULL, *output_event = NULL; |
9994 | struct perf_event *event, *sibling; | |
cdd6c482 | 9995 | struct perf_event_attr attr; |
f63a8daa | 9996 | struct perf_event_context *ctx, *uninitialized_var(gctx); |
cdd6c482 | 9997 | struct file *event_file = NULL; |
2903ff01 | 9998 | struct fd group = {NULL, 0}; |
38a81da2 | 9999 | struct task_struct *task = NULL; |
89a1e187 | 10000 | struct pmu *pmu; |
ea635c64 | 10001 | int event_fd; |
b04243ef | 10002 | int move_group = 0; |
dc86cabe | 10003 | int err; |
a21b0b35 | 10004 | int f_flags = O_RDWR; |
79dff51e | 10005 | int cgroup_fd = -1; |
0793a61d | 10006 | |
2743a5b0 | 10007 | /* for future expandability... */ |
e5d1367f | 10008 | if (flags & ~PERF_FLAG_ALL) |
2743a5b0 PM |
10009 | return -EINVAL; |
10010 | ||
d48d0c64 BH |
10011 | if (perf_paranoid_any() && !capable(CAP_SYS_ADMIN)) |
10012 | return -EACCES; | |
10013 | ||
dc86cabe IM |
10014 | err = perf_copy_attr(attr_uptr, &attr); |
10015 | if (err) | |
10016 | return err; | |
eab656ae | 10017 | |
0764771d PZ |
10018 | if (!attr.exclude_kernel) { |
10019 | if (perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) | |
10020 | return -EACCES; | |
10021 | } | |
10022 | ||
e4222673 HB |
10023 | if (attr.namespaces) { |
10024 | if (!capable(CAP_SYS_ADMIN)) | |
10025 | return -EACCES; | |
10026 | } | |
10027 | ||
df58ab24 | 10028 | if (attr.freq) { |
cdd6c482 | 10029 | if (attr.sample_freq > sysctl_perf_event_sample_rate) |
df58ab24 | 10030 | return -EINVAL; |
0819b2e3 PZ |
10031 | } else { |
10032 | if (attr.sample_period & (1ULL << 63)) | |
10033 | return -EINVAL; | |
df58ab24 PZ |
10034 | } |
10035 | ||
fc7ce9c7 KL |
10036 | /* Only privileged users can get physical addresses */ |
10037 | if ((attr.sample_type & PERF_SAMPLE_PHYS_ADDR) && | |
10038 | perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) | |
10039 | return -EACCES; | |
10040 | ||
97c79a38 ACM |
10041 | if (!attr.sample_max_stack) |
10042 | attr.sample_max_stack = sysctl_perf_event_max_stack; | |
10043 | ||
e5d1367f SE |
10044 | /* |
10045 | * In cgroup mode, the pid argument is used to pass the fd | |
10046 | * opened to the cgroup directory in cgroupfs. The cpu argument | |
10047 | * designates the cpu on which to monitor threads from that | |
10048 | * cgroup. | |
10049 | */ | |
10050 | if ((flags & PERF_FLAG_PID_CGROUP) && (pid == -1 || cpu == -1)) | |
10051 | return -EINVAL; | |
10052 | ||
a21b0b35 YD |
10053 | if (flags & PERF_FLAG_FD_CLOEXEC) |
10054 | f_flags |= O_CLOEXEC; | |
10055 | ||
10056 | event_fd = get_unused_fd_flags(f_flags); | |
ea635c64 AV |
10057 | if (event_fd < 0) |
10058 | return event_fd; | |
10059 | ||
ac9721f3 | 10060 | if (group_fd != -1) { |
2903ff01 AV |
10061 | err = perf_fget_light(group_fd, &group); |
10062 | if (err) | |
d14b12d7 | 10063 | goto err_fd; |
2903ff01 | 10064 | group_leader = group.file->private_data; |
ac9721f3 PZ |
10065 | if (flags & PERF_FLAG_FD_OUTPUT) |
10066 | output_event = group_leader; | |
10067 | if (flags & PERF_FLAG_FD_NO_GROUP) | |
10068 | group_leader = NULL; | |
10069 | } | |
10070 | ||
e5d1367f | 10071 | if (pid != -1 && !(flags & PERF_FLAG_PID_CGROUP)) { |
c6be5a5c PZ |
10072 | task = find_lively_task_by_vpid(pid); |
10073 | if (IS_ERR(task)) { | |
10074 | err = PTR_ERR(task); | |
10075 | goto err_group_fd; | |
10076 | } | |
10077 | } | |
10078 | ||
1f4ee503 PZ |
10079 | if (task && group_leader && |
10080 | group_leader->attr.inherit != attr.inherit) { | |
10081 | err = -EINVAL; | |
10082 | goto err_task; | |
10083 | } | |
10084 | ||
79c9ce57 PZ |
10085 | if (task) { |
10086 | err = mutex_lock_interruptible(&task->signal->cred_guard_mutex); | |
10087 | if (err) | |
e5aeee51 | 10088 | goto err_task; |
79c9ce57 PZ |
10089 | |
10090 | /* | |
10091 | * Reuse ptrace permission checks for now. | |
10092 | * | |
10093 | * We must hold cred_guard_mutex across this and any potential | |
10094 | * perf_install_in_context() call for this new event to | |
10095 | * serialize against exec() altering our credentials (and the | |
10096 | * perf_event_exit_task() that could imply). | |
10097 | */ | |
10098 | err = -EACCES; | |
10099 | if (!ptrace_may_access(task, PTRACE_MODE_READ_REALCREDS)) | |
10100 | goto err_cred; | |
10101 | } | |
10102 | ||
79dff51e MF |
10103 | if (flags & PERF_FLAG_PID_CGROUP) |
10104 | cgroup_fd = pid; | |
10105 | ||
4dc0da86 | 10106 | event = perf_event_alloc(&attr, cpu, task, group_leader, NULL, |
79dff51e | 10107 | NULL, NULL, cgroup_fd); |
d14b12d7 SE |
10108 | if (IS_ERR(event)) { |
10109 | err = PTR_ERR(event); | |
79c9ce57 | 10110 | goto err_cred; |
d14b12d7 SE |
10111 | } |
10112 | ||
53b25335 VW |
10113 | if (is_sampling_event(event)) { |
10114 | if (event->pmu->capabilities & PERF_PMU_CAP_NO_INTERRUPT) { | |
a1396555 | 10115 | err = -EOPNOTSUPP; |
53b25335 VW |
10116 | goto err_alloc; |
10117 | } | |
10118 | } | |
10119 | ||
89a1e187 PZ |
10120 | /* |
10121 | * Special case software events and allow them to be part of | |
10122 | * any hardware group. | |
10123 | */ | |
10124 | pmu = event->pmu; | |
b04243ef | 10125 | |
34f43927 PZ |
10126 | if (attr.use_clockid) { |
10127 | err = perf_event_set_clock(event, attr.clockid); | |
10128 | if (err) | |
10129 | goto err_alloc; | |
10130 | } | |
10131 | ||
4ff6a8de DCC |
10132 | if (pmu->task_ctx_nr == perf_sw_context) |
10133 | event->event_caps |= PERF_EV_CAP_SOFTWARE; | |
10134 | ||
b04243ef PZ |
10135 | if (group_leader && |
10136 | (is_software_event(event) != is_software_event(group_leader))) { | |
10137 | if (is_software_event(event)) { | |
10138 | /* | |
10139 | * If event and group_leader are not both a software | |
10140 | * event, and event is, then group leader is not. | |
10141 | * | |
10142 | * Allow the addition of software events to !software | |
10143 | * groups, this is safe because software events never | |
10144 | * fail to schedule. | |
10145 | */ | |
10146 | pmu = group_leader->pmu; | |
10147 | } else if (is_software_event(group_leader) && | |
4ff6a8de | 10148 | (group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { |
b04243ef PZ |
10149 | /* |
10150 | * In case the group is a pure software group, and we | |
10151 | * try to add a hardware event, move the whole group to | |
10152 | * the hardware context. | |
10153 | */ | |
10154 | move_group = 1; | |
10155 | } | |
10156 | } | |
89a1e187 PZ |
10157 | |
10158 | /* | |
10159 | * Get the target context (task or percpu): | |
10160 | */ | |
4af57ef2 | 10161 | ctx = find_get_context(pmu, task, event); |
89a1e187 PZ |
10162 | if (IS_ERR(ctx)) { |
10163 | err = PTR_ERR(ctx); | |
c6be5a5c | 10164 | goto err_alloc; |
89a1e187 PZ |
10165 | } |
10166 | ||
bed5b25a AS |
10167 | if ((pmu->capabilities & PERF_PMU_CAP_EXCLUSIVE) && group_leader) { |
10168 | err = -EBUSY; | |
10169 | goto err_context; | |
10170 | } | |
10171 | ||
ccff286d | 10172 | /* |
cdd6c482 | 10173 | * Look up the group leader (we will attach this event to it): |
04289bb9 | 10174 | */ |
ac9721f3 | 10175 | if (group_leader) { |
dc86cabe | 10176 | err = -EINVAL; |
04289bb9 | 10177 | |
04289bb9 | 10178 | /* |
ccff286d IM |
10179 | * Do not allow a recursive hierarchy (this new sibling |
10180 | * becoming part of another group-sibling): | |
10181 | */ | |
10182 | if (group_leader->group_leader != group_leader) | |
c3f00c70 | 10183 | goto err_context; |
34f43927 PZ |
10184 | |
10185 | /* All events in a group should have the same clock */ | |
10186 | if (group_leader->clock != event->clock) | |
10187 | goto err_context; | |
10188 | ||
ccff286d | 10189 | /* |
64aee2a9 MR |
10190 | * Make sure we're both events for the same CPU; |
10191 | * grouping events for different CPUs is broken; since | |
10192 | * you can never concurrently schedule them anyhow. | |
04289bb9 | 10193 | */ |
64aee2a9 MR |
10194 | if (group_leader->cpu != event->cpu) |
10195 | goto err_context; | |
c3c87e77 | 10196 | |
64aee2a9 MR |
10197 | /* |
10198 | * Make sure we're both on the same task, or both | |
10199 | * per-CPU events. | |
10200 | */ | |
10201 | if (group_leader->ctx->task != ctx->task) | |
10202 | goto err_context; | |
10203 | ||
10204 | /* | |
10205 | * Do not allow to attach to a group in a different task | |
10206 | * or CPU context. If we're moving SW events, we'll fix | |
10207 | * this up later, so allow that. | |
10208 | */ | |
10209 | if (!move_group && group_leader->ctx != ctx) | |
10210 | goto err_context; | |
b04243ef | 10211 | |
3b6f9e5c PM |
10212 | /* |
10213 | * Only a group leader can be exclusive or pinned | |
10214 | */ | |
0d48696f | 10215 | if (attr.exclusive || attr.pinned) |
c3f00c70 | 10216 | goto err_context; |
ac9721f3 PZ |
10217 | } |
10218 | ||
10219 | if (output_event) { | |
10220 | err = perf_event_set_output(event, output_event); | |
10221 | if (err) | |
c3f00c70 | 10222 | goto err_context; |
ac9721f3 | 10223 | } |
0793a61d | 10224 | |
a21b0b35 YD |
10225 | event_file = anon_inode_getfile("[perf_event]", &perf_fops, event, |
10226 | f_flags); | |
ea635c64 AV |
10227 | if (IS_ERR(event_file)) { |
10228 | err = PTR_ERR(event_file); | |
201c2f85 | 10229 | event_file = NULL; |
c3f00c70 | 10230 | goto err_context; |
ea635c64 | 10231 | } |
9b51f66d | 10232 | |
b04243ef | 10233 | if (move_group) { |
321027c1 PZ |
10234 | gctx = __perf_event_ctx_lock_double(group_leader, ctx); |
10235 | ||
84c4e620 PZ |
10236 | if (gctx->task == TASK_TOMBSTONE) { |
10237 | err = -ESRCH; | |
10238 | goto err_locked; | |
10239 | } | |
321027c1 PZ |
10240 | |
10241 | /* | |
10242 | * Check if we raced against another sys_perf_event_open() call | |
10243 | * moving the software group underneath us. | |
10244 | */ | |
10245 | if (!(group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { | |
10246 | /* | |
10247 | * If someone moved the group out from under us, check | |
10248 | * if this new event wound up on the same ctx, if so | |
10249 | * its the regular !move_group case, otherwise fail. | |
10250 | */ | |
10251 | if (gctx != ctx) { | |
10252 | err = -EINVAL; | |
10253 | goto err_locked; | |
10254 | } else { | |
10255 | perf_event_ctx_unlock(group_leader, gctx); | |
10256 | move_group = 0; | |
10257 | } | |
10258 | } | |
f55fc2a5 PZ |
10259 | } else { |
10260 | mutex_lock(&ctx->mutex); | |
10261 | } | |
10262 | ||
84c4e620 PZ |
10263 | if (ctx->task == TASK_TOMBSTONE) { |
10264 | err = -ESRCH; | |
10265 | goto err_locked; | |
10266 | } | |
10267 | ||
a723968c PZ |
10268 | if (!perf_event_validate_size(event)) { |
10269 | err = -E2BIG; | |
10270 | goto err_locked; | |
10271 | } | |
10272 | ||
a63fbed7 TG |
10273 | if (!task) { |
10274 | /* | |
10275 | * Check if the @cpu we're creating an event for is online. | |
10276 | * | |
10277 | * We use the perf_cpu_context::ctx::mutex to serialize against | |
10278 | * the hotplug notifiers. See perf_event_{init,exit}_cpu(). | |
10279 | */ | |
10280 | struct perf_cpu_context *cpuctx = | |
10281 | container_of(ctx, struct perf_cpu_context, ctx); | |
10282 | ||
10283 | if (!cpuctx->online) { | |
10284 | err = -ENODEV; | |
10285 | goto err_locked; | |
10286 | } | |
10287 | } | |
10288 | ||
10289 | ||
f55fc2a5 PZ |
10290 | /* |
10291 | * Must be under the same ctx::mutex as perf_install_in_context(), | |
10292 | * because we need to serialize with concurrent event creation. | |
10293 | */ | |
10294 | if (!exclusive_event_installable(event, ctx)) { | |
10295 | /* exclusive and group stuff are assumed mutually exclusive */ | |
10296 | WARN_ON_ONCE(move_group); | |
f63a8daa | 10297 | |
f55fc2a5 PZ |
10298 | err = -EBUSY; |
10299 | goto err_locked; | |
10300 | } | |
f63a8daa | 10301 | |
f55fc2a5 PZ |
10302 | WARN_ON_ONCE(ctx->parent_ctx); |
10303 | ||
79c9ce57 PZ |
10304 | /* |
10305 | * This is the point on no return; we cannot fail hereafter. This is | |
10306 | * where we start modifying current state. | |
10307 | */ | |
10308 | ||
f55fc2a5 | 10309 | if (move_group) { |
f63a8daa PZ |
10310 | /* |
10311 | * See perf_event_ctx_lock() for comments on the details | |
10312 | * of swizzling perf_event::ctx. | |
10313 | */ | |
45a0e07a | 10314 | perf_remove_from_context(group_leader, 0); |
279b5165 | 10315 | put_ctx(gctx); |
0231bb53 | 10316 | |
b04243ef PZ |
10317 | list_for_each_entry(sibling, &group_leader->sibling_list, |
10318 | group_entry) { | |
45a0e07a | 10319 | perf_remove_from_context(sibling, 0); |
b04243ef PZ |
10320 | put_ctx(gctx); |
10321 | } | |
b04243ef | 10322 | |
f63a8daa PZ |
10323 | /* |
10324 | * Wait for everybody to stop referencing the events through | |
10325 | * the old lists, before installing it on new lists. | |
10326 | */ | |
0cda4c02 | 10327 | synchronize_rcu(); |
f63a8daa | 10328 | |
8f95b435 PZI |
10329 | /* |
10330 | * Install the group siblings before the group leader. | |
10331 | * | |
10332 | * Because a group leader will try and install the entire group | |
10333 | * (through the sibling list, which is still in-tact), we can | |
10334 | * end up with siblings installed in the wrong context. | |
10335 | * | |
10336 | * By installing siblings first we NO-OP because they're not | |
10337 | * reachable through the group lists. | |
10338 | */ | |
b04243ef PZ |
10339 | list_for_each_entry(sibling, &group_leader->sibling_list, |
10340 | group_entry) { | |
8f95b435 | 10341 | perf_event__state_init(sibling); |
9fc81d87 | 10342 | perf_install_in_context(ctx, sibling, sibling->cpu); |
b04243ef PZ |
10343 | get_ctx(ctx); |
10344 | } | |
8f95b435 PZI |
10345 | |
10346 | /* | |
10347 | * Removing from the context ends up with disabled | |
10348 | * event. What we want here is event in the initial | |
10349 | * startup state, ready to be add into new context. | |
10350 | */ | |
10351 | perf_event__state_init(group_leader); | |
10352 | perf_install_in_context(ctx, group_leader, group_leader->cpu); | |
10353 | get_ctx(ctx); | |
bed5b25a AS |
10354 | } |
10355 | ||
f73e22ab PZ |
10356 | /* |
10357 | * Precalculate sample_data sizes; do while holding ctx::mutex such | |
10358 | * that we're serialized against further additions and before | |
10359 | * perf_install_in_context() which is the point the event is active and | |
10360 | * can use these values. | |
10361 | */ | |
10362 | perf_event__header_size(event); | |
10363 | perf_event__id_header_size(event); | |
10364 | ||
78cd2c74 PZ |
10365 | event->owner = current; |
10366 | ||
e2d37cd2 | 10367 | perf_install_in_context(ctx, event, event->cpu); |
fe4b04fa | 10368 | perf_unpin_context(ctx); |
f63a8daa | 10369 | |
f55fc2a5 | 10370 | if (move_group) |
321027c1 | 10371 | perf_event_ctx_unlock(group_leader, gctx); |
d859e29f | 10372 | mutex_unlock(&ctx->mutex); |
9b51f66d | 10373 | |
79c9ce57 PZ |
10374 | if (task) { |
10375 | mutex_unlock(&task->signal->cred_guard_mutex); | |
10376 | put_task_struct(task); | |
10377 | } | |
10378 | ||
cdd6c482 IM |
10379 | mutex_lock(¤t->perf_event_mutex); |
10380 | list_add_tail(&event->owner_entry, ¤t->perf_event_list); | |
10381 | mutex_unlock(¤t->perf_event_mutex); | |
082ff5a2 | 10382 | |
8a49542c PZ |
10383 | /* |
10384 | * Drop the reference on the group_event after placing the | |
10385 | * new event on the sibling_list. This ensures destruction | |
10386 | * of the group leader will find the pointer to itself in | |
10387 | * perf_group_detach(). | |
10388 | */ | |
2903ff01 | 10389 | fdput(group); |
ea635c64 AV |
10390 | fd_install(event_fd, event_file); |
10391 | return event_fd; | |
0793a61d | 10392 | |
f55fc2a5 PZ |
10393 | err_locked: |
10394 | if (move_group) | |
321027c1 | 10395 | perf_event_ctx_unlock(group_leader, gctx); |
f55fc2a5 PZ |
10396 | mutex_unlock(&ctx->mutex); |
10397 | /* err_file: */ | |
10398 | fput(event_file); | |
c3f00c70 | 10399 | err_context: |
fe4b04fa | 10400 | perf_unpin_context(ctx); |
ea635c64 | 10401 | put_ctx(ctx); |
c6be5a5c | 10402 | err_alloc: |
13005627 PZ |
10403 | /* |
10404 | * If event_file is set, the fput() above will have called ->release() | |
10405 | * and that will take care of freeing the event. | |
10406 | */ | |
10407 | if (!event_file) | |
10408 | free_event(event); | |
79c9ce57 PZ |
10409 | err_cred: |
10410 | if (task) | |
10411 | mutex_unlock(&task->signal->cred_guard_mutex); | |
1f4ee503 | 10412 | err_task: |
e7d0bc04 PZ |
10413 | if (task) |
10414 | put_task_struct(task); | |
89a1e187 | 10415 | err_group_fd: |
2903ff01 | 10416 | fdput(group); |
ea635c64 AV |
10417 | err_fd: |
10418 | put_unused_fd(event_fd); | |
dc86cabe | 10419 | return err; |
0793a61d TG |
10420 | } |
10421 | ||
fb0459d7 AV |
10422 | /** |
10423 | * perf_event_create_kernel_counter | |
10424 | * | |
10425 | * @attr: attributes of the counter to create | |
10426 | * @cpu: cpu in which the counter is bound | |
38a81da2 | 10427 | * @task: task to profile (NULL for percpu) |
fb0459d7 AV |
10428 | */ |
10429 | struct perf_event * | |
10430 | perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, | |
38a81da2 | 10431 | struct task_struct *task, |
4dc0da86 AK |
10432 | perf_overflow_handler_t overflow_handler, |
10433 | void *context) | |
fb0459d7 | 10434 | { |
fb0459d7 | 10435 | struct perf_event_context *ctx; |
c3f00c70 | 10436 | struct perf_event *event; |
fb0459d7 | 10437 | int err; |
d859e29f | 10438 | |
fb0459d7 AV |
10439 | /* |
10440 | * Get the target context (task or percpu): | |
10441 | */ | |
d859e29f | 10442 | |
4dc0da86 | 10443 | event = perf_event_alloc(attr, cpu, task, NULL, NULL, |
79dff51e | 10444 | overflow_handler, context, -1); |
c3f00c70 PZ |
10445 | if (IS_ERR(event)) { |
10446 | err = PTR_ERR(event); | |
10447 | goto err; | |
10448 | } | |
d859e29f | 10449 | |
f8697762 | 10450 | /* Mark owner so we could distinguish it from user events. */ |
63b6da39 | 10451 | event->owner = TASK_TOMBSTONE; |
f8697762 | 10452 | |
4af57ef2 | 10453 | ctx = find_get_context(event->pmu, task, event); |
c6567f64 FW |
10454 | if (IS_ERR(ctx)) { |
10455 | err = PTR_ERR(ctx); | |
c3f00c70 | 10456 | goto err_free; |
d859e29f | 10457 | } |
fb0459d7 | 10458 | |
fb0459d7 AV |
10459 | WARN_ON_ONCE(ctx->parent_ctx); |
10460 | mutex_lock(&ctx->mutex); | |
84c4e620 PZ |
10461 | if (ctx->task == TASK_TOMBSTONE) { |
10462 | err = -ESRCH; | |
10463 | goto err_unlock; | |
10464 | } | |
10465 | ||
a63fbed7 TG |
10466 | if (!task) { |
10467 | /* | |
10468 | * Check if the @cpu we're creating an event for is online. | |
10469 | * | |
10470 | * We use the perf_cpu_context::ctx::mutex to serialize against | |
10471 | * the hotplug notifiers. See perf_event_{init,exit}_cpu(). | |
10472 | */ | |
10473 | struct perf_cpu_context *cpuctx = | |
10474 | container_of(ctx, struct perf_cpu_context, ctx); | |
10475 | if (!cpuctx->online) { | |
10476 | err = -ENODEV; | |
10477 | goto err_unlock; | |
10478 | } | |
10479 | } | |
10480 | ||
bed5b25a | 10481 | if (!exclusive_event_installable(event, ctx)) { |
bed5b25a | 10482 | err = -EBUSY; |
84c4e620 | 10483 | goto err_unlock; |
bed5b25a AS |
10484 | } |
10485 | ||
d862c730 | 10486 | perf_install_in_context(ctx, event, event->cpu); |
fe4b04fa | 10487 | perf_unpin_context(ctx); |
fb0459d7 AV |
10488 | mutex_unlock(&ctx->mutex); |
10489 | ||
fb0459d7 AV |
10490 | return event; |
10491 | ||
84c4e620 PZ |
10492 | err_unlock: |
10493 | mutex_unlock(&ctx->mutex); | |
10494 | perf_unpin_context(ctx); | |
10495 | put_ctx(ctx); | |
c3f00c70 PZ |
10496 | err_free: |
10497 | free_event(event); | |
10498 | err: | |
c6567f64 | 10499 | return ERR_PTR(err); |
9b51f66d | 10500 | } |
fb0459d7 | 10501 | EXPORT_SYMBOL_GPL(perf_event_create_kernel_counter); |
9b51f66d | 10502 | |
0cda4c02 YZ |
10503 | void perf_pmu_migrate_context(struct pmu *pmu, int src_cpu, int dst_cpu) |
10504 | { | |
10505 | struct perf_event_context *src_ctx; | |
10506 | struct perf_event_context *dst_ctx; | |
10507 | struct perf_event *event, *tmp; | |
10508 | LIST_HEAD(events); | |
10509 | ||
10510 | src_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, src_cpu)->ctx; | |
10511 | dst_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, dst_cpu)->ctx; | |
10512 | ||
f63a8daa PZ |
10513 | /* |
10514 | * See perf_event_ctx_lock() for comments on the details | |
10515 | * of swizzling perf_event::ctx. | |
10516 | */ | |
10517 | mutex_lock_double(&src_ctx->mutex, &dst_ctx->mutex); | |
0cda4c02 YZ |
10518 | list_for_each_entry_safe(event, tmp, &src_ctx->event_list, |
10519 | event_entry) { | |
45a0e07a | 10520 | perf_remove_from_context(event, 0); |
9a545de0 | 10521 | unaccount_event_cpu(event, src_cpu); |
0cda4c02 | 10522 | put_ctx(src_ctx); |
9886167d | 10523 | list_add(&event->migrate_entry, &events); |
0cda4c02 | 10524 | } |
0cda4c02 | 10525 | |
8f95b435 PZI |
10526 | /* |
10527 | * Wait for the events to quiesce before re-instating them. | |
10528 | */ | |
0cda4c02 YZ |
10529 | synchronize_rcu(); |
10530 | ||
8f95b435 PZI |
10531 | /* |
10532 | * Re-instate events in 2 passes. | |
10533 | * | |
10534 | * Skip over group leaders and only install siblings on this first | |
10535 | * pass, siblings will not get enabled without a leader, however a | |
10536 | * leader will enable its siblings, even if those are still on the old | |
10537 | * context. | |
10538 | */ | |
10539 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { | |
10540 | if (event->group_leader == event) | |
10541 | continue; | |
10542 | ||
10543 | list_del(&event->migrate_entry); | |
10544 | if (event->state >= PERF_EVENT_STATE_OFF) | |
10545 | event->state = PERF_EVENT_STATE_INACTIVE; | |
10546 | account_event_cpu(event, dst_cpu); | |
10547 | perf_install_in_context(dst_ctx, event, dst_cpu); | |
10548 | get_ctx(dst_ctx); | |
10549 | } | |
10550 | ||
10551 | /* | |
10552 | * Once all the siblings are setup properly, install the group leaders | |
10553 | * to make it go. | |
10554 | */ | |
9886167d PZ |
10555 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { |
10556 | list_del(&event->migrate_entry); | |
0cda4c02 YZ |
10557 | if (event->state >= PERF_EVENT_STATE_OFF) |
10558 | event->state = PERF_EVENT_STATE_INACTIVE; | |
9a545de0 | 10559 | account_event_cpu(event, dst_cpu); |
0cda4c02 YZ |
10560 | perf_install_in_context(dst_ctx, event, dst_cpu); |
10561 | get_ctx(dst_ctx); | |
10562 | } | |
10563 | mutex_unlock(&dst_ctx->mutex); | |
f63a8daa | 10564 | mutex_unlock(&src_ctx->mutex); |
0cda4c02 YZ |
10565 | } |
10566 | EXPORT_SYMBOL_GPL(perf_pmu_migrate_context); | |
10567 | ||
cdd6c482 | 10568 | static void sync_child_event(struct perf_event *child_event, |
38b200d6 | 10569 | struct task_struct *child) |
d859e29f | 10570 | { |
cdd6c482 | 10571 | struct perf_event *parent_event = child_event->parent; |
8bc20959 | 10572 | u64 child_val; |
d859e29f | 10573 | |
cdd6c482 IM |
10574 | if (child_event->attr.inherit_stat) |
10575 | perf_event_read_event(child_event, child); | |
38b200d6 | 10576 | |
b5e58793 | 10577 | child_val = perf_event_count(child_event); |
d859e29f PM |
10578 | |
10579 | /* | |
10580 | * Add back the child's count to the parent's count: | |
10581 | */ | |
a6e6dea6 | 10582 | atomic64_add(child_val, &parent_event->child_count); |
cdd6c482 IM |
10583 | atomic64_add(child_event->total_time_enabled, |
10584 | &parent_event->child_total_time_enabled); | |
10585 | atomic64_add(child_event->total_time_running, | |
10586 | &parent_event->child_total_time_running); | |
d859e29f PM |
10587 | } |
10588 | ||
9b51f66d | 10589 | static void |
8ba289b8 PZ |
10590 | perf_event_exit_event(struct perf_event *child_event, |
10591 | struct perf_event_context *child_ctx, | |
10592 | struct task_struct *child) | |
9b51f66d | 10593 | { |
8ba289b8 PZ |
10594 | struct perf_event *parent_event = child_event->parent; |
10595 | ||
1903d50c PZ |
10596 | /* |
10597 | * Do not destroy the 'original' grouping; because of the context | |
10598 | * switch optimization the original events could've ended up in a | |
10599 | * random child task. | |
10600 | * | |
10601 | * If we were to destroy the original group, all group related | |
10602 | * operations would cease to function properly after this random | |
10603 | * child dies. | |
10604 | * | |
10605 | * Do destroy all inherited groups, we don't care about those | |
10606 | * and being thorough is better. | |
10607 | */ | |
32132a3d PZ |
10608 | raw_spin_lock_irq(&child_ctx->lock); |
10609 | WARN_ON_ONCE(child_ctx->is_active); | |
10610 | ||
8ba289b8 | 10611 | if (parent_event) |
32132a3d PZ |
10612 | perf_group_detach(child_event); |
10613 | list_del_event(child_event, child_ctx); | |
0d3d73aa | 10614 | perf_event_set_state(child_event, PERF_EVENT_STATE_EXIT); /* is_event_hup() */ |
32132a3d | 10615 | raw_spin_unlock_irq(&child_ctx->lock); |
0cc0c027 | 10616 | |
9b51f66d | 10617 | /* |
8ba289b8 | 10618 | * Parent events are governed by their filedesc, retain them. |
9b51f66d | 10619 | */ |
8ba289b8 | 10620 | if (!parent_event) { |
179033b3 | 10621 | perf_event_wakeup(child_event); |
8ba289b8 | 10622 | return; |
4bcf349a | 10623 | } |
8ba289b8 PZ |
10624 | /* |
10625 | * Child events can be cleaned up. | |
10626 | */ | |
10627 | ||
10628 | sync_child_event(child_event, child); | |
10629 | ||
10630 | /* | |
10631 | * Remove this event from the parent's list | |
10632 | */ | |
10633 | WARN_ON_ONCE(parent_event->ctx->parent_ctx); | |
10634 | mutex_lock(&parent_event->child_mutex); | |
10635 | list_del_init(&child_event->child_list); | |
10636 | mutex_unlock(&parent_event->child_mutex); | |
10637 | ||
10638 | /* | |
10639 | * Kick perf_poll() for is_event_hup(). | |
10640 | */ | |
10641 | perf_event_wakeup(parent_event); | |
10642 | free_event(child_event); | |
10643 | put_event(parent_event); | |
9b51f66d IM |
10644 | } |
10645 | ||
8dc85d54 | 10646 | static void perf_event_exit_task_context(struct task_struct *child, int ctxn) |
9b51f66d | 10647 | { |
211de6eb | 10648 | struct perf_event_context *child_ctx, *clone_ctx = NULL; |
63b6da39 | 10649 | struct perf_event *child_event, *next; |
63b6da39 PZ |
10650 | |
10651 | WARN_ON_ONCE(child != current); | |
9b51f66d | 10652 | |
6a3351b6 | 10653 | child_ctx = perf_pin_task_context(child, ctxn); |
63b6da39 | 10654 | if (!child_ctx) |
9b51f66d IM |
10655 | return; |
10656 | ||
ad3a37de | 10657 | /* |
6a3351b6 PZ |
10658 | * In order to reduce the amount of tricky in ctx tear-down, we hold |
10659 | * ctx::mutex over the entire thing. This serializes against almost | |
10660 | * everything that wants to access the ctx. | |
10661 | * | |
10662 | * The exception is sys_perf_event_open() / | |
10663 | * perf_event_create_kernel_count() which does find_get_context() | |
10664 | * without ctx::mutex (it cannot because of the move_group double mutex | |
10665 | * lock thing). See the comments in perf_install_in_context(). | |
ad3a37de | 10666 | */ |
6a3351b6 | 10667 | mutex_lock(&child_ctx->mutex); |
c93f7669 PM |
10668 | |
10669 | /* | |
6a3351b6 PZ |
10670 | * In a single ctx::lock section, de-schedule the events and detach the |
10671 | * context from the task such that we cannot ever get it scheduled back | |
10672 | * in. | |
c93f7669 | 10673 | */ |
6a3351b6 | 10674 | raw_spin_lock_irq(&child_ctx->lock); |
487f05e1 | 10675 | task_ctx_sched_out(__get_cpu_context(child_ctx), child_ctx, EVENT_ALL); |
4a1c0f26 | 10676 | |
71a851b4 | 10677 | /* |
63b6da39 PZ |
10678 | * Now that the context is inactive, destroy the task <-> ctx relation |
10679 | * and mark the context dead. | |
71a851b4 | 10680 | */ |
63b6da39 PZ |
10681 | RCU_INIT_POINTER(child->perf_event_ctxp[ctxn], NULL); |
10682 | put_ctx(child_ctx); /* cannot be last */ | |
10683 | WRITE_ONCE(child_ctx->task, TASK_TOMBSTONE); | |
10684 | put_task_struct(current); /* cannot be last */ | |
4a1c0f26 | 10685 | |
211de6eb | 10686 | clone_ctx = unclone_ctx(child_ctx); |
6a3351b6 | 10687 | raw_spin_unlock_irq(&child_ctx->lock); |
9f498cc5 | 10688 | |
211de6eb PZ |
10689 | if (clone_ctx) |
10690 | put_ctx(clone_ctx); | |
4a1c0f26 | 10691 | |
9f498cc5 | 10692 | /* |
cdd6c482 IM |
10693 | * Report the task dead after unscheduling the events so that we |
10694 | * won't get any samples after PERF_RECORD_EXIT. We can however still | |
10695 | * get a few PERF_RECORD_READ events. | |
9f498cc5 | 10696 | */ |
cdd6c482 | 10697 | perf_event_task(child, child_ctx, 0); |
a63eaf34 | 10698 | |
ebf905fc | 10699 | list_for_each_entry_safe(child_event, next, &child_ctx->event_list, event_entry) |
8ba289b8 | 10700 | perf_event_exit_event(child_event, child_ctx, child); |
8bc20959 | 10701 | |
a63eaf34 PM |
10702 | mutex_unlock(&child_ctx->mutex); |
10703 | ||
10704 | put_ctx(child_ctx); | |
9b51f66d IM |
10705 | } |
10706 | ||
8dc85d54 PZ |
10707 | /* |
10708 | * When a child task exits, feed back event values to parent events. | |
79c9ce57 PZ |
10709 | * |
10710 | * Can be called with cred_guard_mutex held when called from | |
10711 | * install_exec_creds(). | |
8dc85d54 PZ |
10712 | */ |
10713 | void perf_event_exit_task(struct task_struct *child) | |
10714 | { | |
8882135b | 10715 | struct perf_event *event, *tmp; |
8dc85d54 PZ |
10716 | int ctxn; |
10717 | ||
8882135b PZ |
10718 | mutex_lock(&child->perf_event_mutex); |
10719 | list_for_each_entry_safe(event, tmp, &child->perf_event_list, | |
10720 | owner_entry) { | |
10721 | list_del_init(&event->owner_entry); | |
10722 | ||
10723 | /* | |
10724 | * Ensure the list deletion is visible before we clear | |
10725 | * the owner, closes a race against perf_release() where | |
10726 | * we need to serialize on the owner->perf_event_mutex. | |
10727 | */ | |
f47c02c0 | 10728 | smp_store_release(&event->owner, NULL); |
8882135b PZ |
10729 | } |
10730 | mutex_unlock(&child->perf_event_mutex); | |
10731 | ||
8dc85d54 PZ |
10732 | for_each_task_context_nr(ctxn) |
10733 | perf_event_exit_task_context(child, ctxn); | |
4e93ad60 JO |
10734 | |
10735 | /* | |
10736 | * The perf_event_exit_task_context calls perf_event_task | |
10737 | * with child's task_ctx, which generates EXIT events for | |
10738 | * child contexts and sets child->perf_event_ctxp[] to NULL. | |
10739 | * At this point we need to send EXIT events to cpu contexts. | |
10740 | */ | |
10741 | perf_event_task(child, NULL, 0); | |
8dc85d54 PZ |
10742 | } |
10743 | ||
889ff015 FW |
10744 | static void perf_free_event(struct perf_event *event, |
10745 | struct perf_event_context *ctx) | |
10746 | { | |
10747 | struct perf_event *parent = event->parent; | |
10748 | ||
10749 | if (WARN_ON_ONCE(!parent)) | |
10750 | return; | |
10751 | ||
10752 | mutex_lock(&parent->child_mutex); | |
10753 | list_del_init(&event->child_list); | |
10754 | mutex_unlock(&parent->child_mutex); | |
10755 | ||
a6fa941d | 10756 | put_event(parent); |
889ff015 | 10757 | |
652884fe | 10758 | raw_spin_lock_irq(&ctx->lock); |
8a49542c | 10759 | perf_group_detach(event); |
889ff015 | 10760 | list_del_event(event, ctx); |
652884fe | 10761 | raw_spin_unlock_irq(&ctx->lock); |
889ff015 FW |
10762 | free_event(event); |
10763 | } | |
10764 | ||
bbbee908 | 10765 | /* |
652884fe | 10766 | * Free an unexposed, unused context as created by inheritance by |
8dc85d54 | 10767 | * perf_event_init_task below, used by fork() in case of fail. |
652884fe PZ |
10768 | * |
10769 | * Not all locks are strictly required, but take them anyway to be nice and | |
10770 | * help out with the lockdep assertions. | |
bbbee908 | 10771 | */ |
cdd6c482 | 10772 | void perf_event_free_task(struct task_struct *task) |
bbbee908 | 10773 | { |
8dc85d54 | 10774 | struct perf_event_context *ctx; |
cdd6c482 | 10775 | struct perf_event *event, *tmp; |
8dc85d54 | 10776 | int ctxn; |
bbbee908 | 10777 | |
8dc85d54 PZ |
10778 | for_each_task_context_nr(ctxn) { |
10779 | ctx = task->perf_event_ctxp[ctxn]; | |
10780 | if (!ctx) | |
10781 | continue; | |
bbbee908 | 10782 | |
8dc85d54 | 10783 | mutex_lock(&ctx->mutex); |
e552a838 PZ |
10784 | raw_spin_lock_irq(&ctx->lock); |
10785 | /* | |
10786 | * Destroy the task <-> ctx relation and mark the context dead. | |
10787 | * | |
10788 | * This is important because even though the task hasn't been | |
10789 | * exposed yet the context has been (through child_list). | |
10790 | */ | |
10791 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], NULL); | |
10792 | WRITE_ONCE(ctx->task, TASK_TOMBSTONE); | |
10793 | put_task_struct(task); /* cannot be last */ | |
10794 | raw_spin_unlock_irq(&ctx->lock); | |
bbbee908 | 10795 | |
15121c78 | 10796 | list_for_each_entry_safe(event, tmp, &ctx->event_list, event_entry) |
8dc85d54 | 10797 | perf_free_event(event, ctx); |
bbbee908 | 10798 | |
8dc85d54 | 10799 | mutex_unlock(&ctx->mutex); |
8dc85d54 PZ |
10800 | put_ctx(ctx); |
10801 | } | |
889ff015 FW |
10802 | } |
10803 | ||
4e231c79 PZ |
10804 | void perf_event_delayed_put(struct task_struct *task) |
10805 | { | |
10806 | int ctxn; | |
10807 | ||
10808 | for_each_task_context_nr(ctxn) | |
10809 | WARN_ON_ONCE(task->perf_event_ctxp[ctxn]); | |
10810 | } | |
10811 | ||
e03e7ee3 | 10812 | struct file *perf_event_get(unsigned int fd) |
ffe8690c | 10813 | { |
e03e7ee3 | 10814 | struct file *file; |
ffe8690c | 10815 | |
e03e7ee3 AS |
10816 | file = fget_raw(fd); |
10817 | if (!file) | |
10818 | return ERR_PTR(-EBADF); | |
ffe8690c | 10819 | |
e03e7ee3 AS |
10820 | if (file->f_op != &perf_fops) { |
10821 | fput(file); | |
10822 | return ERR_PTR(-EBADF); | |
10823 | } | |
ffe8690c | 10824 | |
e03e7ee3 | 10825 | return file; |
ffe8690c KX |
10826 | } |
10827 | ||
10828 | const struct perf_event_attr *perf_event_attrs(struct perf_event *event) | |
10829 | { | |
10830 | if (!event) | |
10831 | return ERR_PTR(-EINVAL); | |
10832 | ||
10833 | return &event->attr; | |
10834 | } | |
10835 | ||
97dee4f3 | 10836 | /* |
d8a8cfc7 PZ |
10837 | * Inherit a event from parent task to child task. |
10838 | * | |
10839 | * Returns: | |
10840 | * - valid pointer on success | |
10841 | * - NULL for orphaned events | |
10842 | * - IS_ERR() on error | |
97dee4f3 PZ |
10843 | */ |
10844 | static struct perf_event * | |
10845 | inherit_event(struct perf_event *parent_event, | |
10846 | struct task_struct *parent, | |
10847 | struct perf_event_context *parent_ctx, | |
10848 | struct task_struct *child, | |
10849 | struct perf_event *group_leader, | |
10850 | struct perf_event_context *child_ctx) | |
10851 | { | |
8ca2bd41 | 10852 | enum perf_event_state parent_state = parent_event->state; |
97dee4f3 | 10853 | struct perf_event *child_event; |
cee010ec | 10854 | unsigned long flags; |
97dee4f3 PZ |
10855 | |
10856 | /* | |
10857 | * Instead of creating recursive hierarchies of events, | |
10858 | * we link inherited events back to the original parent, | |
10859 | * which has a filp for sure, which we use as the reference | |
10860 | * count: | |
10861 | */ | |
10862 | if (parent_event->parent) | |
10863 | parent_event = parent_event->parent; | |
10864 | ||
10865 | child_event = perf_event_alloc(&parent_event->attr, | |
10866 | parent_event->cpu, | |
d580ff86 | 10867 | child, |
97dee4f3 | 10868 | group_leader, parent_event, |
79dff51e | 10869 | NULL, NULL, -1); |
97dee4f3 PZ |
10870 | if (IS_ERR(child_event)) |
10871 | return child_event; | |
a6fa941d | 10872 | |
c6e5b732 PZ |
10873 | /* |
10874 | * is_orphaned_event() and list_add_tail(&parent_event->child_list) | |
10875 | * must be under the same lock in order to serialize against | |
10876 | * perf_event_release_kernel(), such that either we must observe | |
10877 | * is_orphaned_event() or they will observe us on the child_list. | |
10878 | */ | |
10879 | mutex_lock(&parent_event->child_mutex); | |
fadfe7be JO |
10880 | if (is_orphaned_event(parent_event) || |
10881 | !atomic_long_inc_not_zero(&parent_event->refcount)) { | |
c6e5b732 | 10882 | mutex_unlock(&parent_event->child_mutex); |
a6fa941d AV |
10883 | free_event(child_event); |
10884 | return NULL; | |
10885 | } | |
10886 | ||
97dee4f3 PZ |
10887 | get_ctx(child_ctx); |
10888 | ||
10889 | /* | |
10890 | * Make the child state follow the state of the parent event, | |
10891 | * not its attr.disabled bit. We hold the parent's mutex, | |
10892 | * so we won't race with perf_event_{en, dis}able_family. | |
10893 | */ | |
1929def9 | 10894 | if (parent_state >= PERF_EVENT_STATE_INACTIVE) |
97dee4f3 PZ |
10895 | child_event->state = PERF_EVENT_STATE_INACTIVE; |
10896 | else | |
10897 | child_event->state = PERF_EVENT_STATE_OFF; | |
10898 | ||
10899 | if (parent_event->attr.freq) { | |
10900 | u64 sample_period = parent_event->hw.sample_period; | |
10901 | struct hw_perf_event *hwc = &child_event->hw; | |
10902 | ||
10903 | hwc->sample_period = sample_period; | |
10904 | hwc->last_period = sample_period; | |
10905 | ||
10906 | local64_set(&hwc->period_left, sample_period); | |
10907 | } | |
10908 | ||
10909 | child_event->ctx = child_ctx; | |
10910 | child_event->overflow_handler = parent_event->overflow_handler; | |
4dc0da86 AK |
10911 | child_event->overflow_handler_context |
10912 | = parent_event->overflow_handler_context; | |
97dee4f3 | 10913 | |
614b6780 TG |
10914 | /* |
10915 | * Precalculate sample_data sizes | |
10916 | */ | |
10917 | perf_event__header_size(child_event); | |
6844c09d | 10918 | perf_event__id_header_size(child_event); |
614b6780 | 10919 | |
97dee4f3 PZ |
10920 | /* |
10921 | * Link it up in the child's context: | |
10922 | */ | |
cee010ec | 10923 | raw_spin_lock_irqsave(&child_ctx->lock, flags); |
97dee4f3 | 10924 | add_event_to_ctx(child_event, child_ctx); |
cee010ec | 10925 | raw_spin_unlock_irqrestore(&child_ctx->lock, flags); |
97dee4f3 | 10926 | |
97dee4f3 PZ |
10927 | /* |
10928 | * Link this into the parent event's child list | |
10929 | */ | |
97dee4f3 PZ |
10930 | list_add_tail(&child_event->child_list, &parent_event->child_list); |
10931 | mutex_unlock(&parent_event->child_mutex); | |
10932 | ||
10933 | return child_event; | |
10934 | } | |
10935 | ||
d8a8cfc7 PZ |
10936 | /* |
10937 | * Inherits an event group. | |
10938 | * | |
10939 | * This will quietly suppress orphaned events; !inherit_event() is not an error. | |
10940 | * This matches with perf_event_release_kernel() removing all child events. | |
10941 | * | |
10942 | * Returns: | |
10943 | * - 0 on success | |
10944 | * - <0 on error | |
10945 | */ | |
97dee4f3 PZ |
10946 | static int inherit_group(struct perf_event *parent_event, |
10947 | struct task_struct *parent, | |
10948 | struct perf_event_context *parent_ctx, | |
10949 | struct task_struct *child, | |
10950 | struct perf_event_context *child_ctx) | |
10951 | { | |
10952 | struct perf_event *leader; | |
10953 | struct perf_event *sub; | |
10954 | struct perf_event *child_ctr; | |
10955 | ||
10956 | leader = inherit_event(parent_event, parent, parent_ctx, | |
10957 | child, NULL, child_ctx); | |
10958 | if (IS_ERR(leader)) | |
10959 | return PTR_ERR(leader); | |
d8a8cfc7 PZ |
10960 | /* |
10961 | * @leader can be NULL here because of is_orphaned_event(). In this | |
10962 | * case inherit_event() will create individual events, similar to what | |
10963 | * perf_group_detach() would do anyway. | |
10964 | */ | |
97dee4f3 PZ |
10965 | list_for_each_entry(sub, &parent_event->sibling_list, group_entry) { |
10966 | child_ctr = inherit_event(sub, parent, parent_ctx, | |
10967 | child, leader, child_ctx); | |
10968 | if (IS_ERR(child_ctr)) | |
10969 | return PTR_ERR(child_ctr); | |
10970 | } | |
10971 | return 0; | |
889ff015 FW |
10972 | } |
10973 | ||
d8a8cfc7 PZ |
10974 | /* |
10975 | * Creates the child task context and tries to inherit the event-group. | |
10976 | * | |
10977 | * Clears @inherited_all on !attr.inherited or error. Note that we'll leave | |
10978 | * inherited_all set when we 'fail' to inherit an orphaned event; this is | |
10979 | * consistent with perf_event_release_kernel() removing all child events. | |
10980 | * | |
10981 | * Returns: | |
10982 | * - 0 on success | |
10983 | * - <0 on error | |
10984 | */ | |
889ff015 FW |
10985 | static int |
10986 | inherit_task_group(struct perf_event *event, struct task_struct *parent, | |
10987 | struct perf_event_context *parent_ctx, | |
8dc85d54 | 10988 | struct task_struct *child, int ctxn, |
889ff015 FW |
10989 | int *inherited_all) |
10990 | { | |
10991 | int ret; | |
8dc85d54 | 10992 | struct perf_event_context *child_ctx; |
889ff015 FW |
10993 | |
10994 | if (!event->attr.inherit) { | |
10995 | *inherited_all = 0; | |
10996 | return 0; | |
bbbee908 PZ |
10997 | } |
10998 | ||
fe4b04fa | 10999 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 FW |
11000 | if (!child_ctx) { |
11001 | /* | |
11002 | * This is executed from the parent task context, so | |
11003 | * inherit events that have been marked for cloning. | |
11004 | * First allocate and initialize a context for the | |
11005 | * child. | |
11006 | */ | |
734df5ab | 11007 | child_ctx = alloc_perf_context(parent_ctx->pmu, child); |
889ff015 FW |
11008 | if (!child_ctx) |
11009 | return -ENOMEM; | |
bbbee908 | 11010 | |
8dc85d54 | 11011 | child->perf_event_ctxp[ctxn] = child_ctx; |
889ff015 FW |
11012 | } |
11013 | ||
11014 | ret = inherit_group(event, parent, parent_ctx, | |
11015 | child, child_ctx); | |
11016 | ||
11017 | if (ret) | |
11018 | *inherited_all = 0; | |
11019 | ||
11020 | return ret; | |
bbbee908 PZ |
11021 | } |
11022 | ||
9b51f66d | 11023 | /* |
cdd6c482 | 11024 | * Initialize the perf_event context in task_struct |
9b51f66d | 11025 | */ |
985c8dcb | 11026 | static int perf_event_init_context(struct task_struct *child, int ctxn) |
9b51f66d | 11027 | { |
889ff015 | 11028 | struct perf_event_context *child_ctx, *parent_ctx; |
cdd6c482 IM |
11029 | struct perf_event_context *cloned_ctx; |
11030 | struct perf_event *event; | |
9b51f66d | 11031 | struct task_struct *parent = current; |
564c2b21 | 11032 | int inherited_all = 1; |
dddd3379 | 11033 | unsigned long flags; |
6ab423e0 | 11034 | int ret = 0; |
9b51f66d | 11035 | |
8dc85d54 | 11036 | if (likely(!parent->perf_event_ctxp[ctxn])) |
6ab423e0 PZ |
11037 | return 0; |
11038 | ||
ad3a37de | 11039 | /* |
25346b93 PM |
11040 | * If the parent's context is a clone, pin it so it won't get |
11041 | * swapped under us. | |
ad3a37de | 11042 | */ |
8dc85d54 | 11043 | parent_ctx = perf_pin_task_context(parent, ctxn); |
ffb4ef21 PZ |
11044 | if (!parent_ctx) |
11045 | return 0; | |
25346b93 | 11046 | |
ad3a37de PM |
11047 | /* |
11048 | * No need to check if parent_ctx != NULL here; since we saw | |
11049 | * it non-NULL earlier, the only reason for it to become NULL | |
11050 | * is if we exit, and since we're currently in the middle of | |
11051 | * a fork we can't be exiting at the same time. | |
11052 | */ | |
ad3a37de | 11053 | |
9b51f66d IM |
11054 | /* |
11055 | * Lock the parent list. No need to lock the child - not PID | |
11056 | * hashed yet and not running, so nobody can access it. | |
11057 | */ | |
d859e29f | 11058 | mutex_lock(&parent_ctx->mutex); |
9b51f66d IM |
11059 | |
11060 | /* | |
11061 | * We dont have to disable NMIs - we are only looking at | |
11062 | * the list, not manipulating it: | |
11063 | */ | |
889ff015 | 11064 | list_for_each_entry(event, &parent_ctx->pinned_groups, group_entry) { |
8dc85d54 PZ |
11065 | ret = inherit_task_group(event, parent, parent_ctx, |
11066 | child, ctxn, &inherited_all); | |
889ff015 | 11067 | if (ret) |
e7cc4865 | 11068 | goto out_unlock; |
889ff015 | 11069 | } |
b93f7978 | 11070 | |
dddd3379 TG |
11071 | /* |
11072 | * We can't hold ctx->lock when iterating the ->flexible_group list due | |
11073 | * to allocations, but we need to prevent rotation because | |
11074 | * rotate_ctx() will change the list from interrupt context. | |
11075 | */ | |
11076 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); | |
11077 | parent_ctx->rotate_disable = 1; | |
11078 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); | |
11079 | ||
889ff015 | 11080 | list_for_each_entry(event, &parent_ctx->flexible_groups, group_entry) { |
8dc85d54 PZ |
11081 | ret = inherit_task_group(event, parent, parent_ctx, |
11082 | child, ctxn, &inherited_all); | |
889ff015 | 11083 | if (ret) |
e7cc4865 | 11084 | goto out_unlock; |
564c2b21 PM |
11085 | } |
11086 | ||
dddd3379 TG |
11087 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); |
11088 | parent_ctx->rotate_disable = 0; | |
dddd3379 | 11089 | |
8dc85d54 | 11090 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 | 11091 | |
05cbaa28 | 11092 | if (child_ctx && inherited_all) { |
564c2b21 PM |
11093 | /* |
11094 | * Mark the child context as a clone of the parent | |
11095 | * context, or of whatever the parent is a clone of. | |
c5ed5145 PZ |
11096 | * |
11097 | * Note that if the parent is a clone, the holding of | |
11098 | * parent_ctx->lock avoids it from being uncloned. | |
564c2b21 | 11099 | */ |
c5ed5145 | 11100 | cloned_ctx = parent_ctx->parent_ctx; |
ad3a37de PM |
11101 | if (cloned_ctx) { |
11102 | child_ctx->parent_ctx = cloned_ctx; | |
25346b93 | 11103 | child_ctx->parent_gen = parent_ctx->parent_gen; |
564c2b21 PM |
11104 | } else { |
11105 | child_ctx->parent_ctx = parent_ctx; | |
11106 | child_ctx->parent_gen = parent_ctx->generation; | |
11107 | } | |
11108 | get_ctx(child_ctx->parent_ctx); | |
9b51f66d IM |
11109 | } |
11110 | ||
c5ed5145 | 11111 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); |
e7cc4865 | 11112 | out_unlock: |
d859e29f | 11113 | mutex_unlock(&parent_ctx->mutex); |
6ab423e0 | 11114 | |
25346b93 | 11115 | perf_unpin_context(parent_ctx); |
fe4b04fa | 11116 | put_ctx(parent_ctx); |
ad3a37de | 11117 | |
6ab423e0 | 11118 | return ret; |
9b51f66d IM |
11119 | } |
11120 | ||
8dc85d54 PZ |
11121 | /* |
11122 | * Initialize the perf_event context in task_struct | |
11123 | */ | |
11124 | int perf_event_init_task(struct task_struct *child) | |
11125 | { | |
11126 | int ctxn, ret; | |
11127 | ||
8550d7cb ON |
11128 | memset(child->perf_event_ctxp, 0, sizeof(child->perf_event_ctxp)); |
11129 | mutex_init(&child->perf_event_mutex); | |
11130 | INIT_LIST_HEAD(&child->perf_event_list); | |
11131 | ||
8dc85d54 PZ |
11132 | for_each_task_context_nr(ctxn) { |
11133 | ret = perf_event_init_context(child, ctxn); | |
6c72e350 PZ |
11134 | if (ret) { |
11135 | perf_event_free_task(child); | |
8dc85d54 | 11136 | return ret; |
6c72e350 | 11137 | } |
8dc85d54 PZ |
11138 | } |
11139 | ||
11140 | return 0; | |
11141 | } | |
11142 | ||
220b140b PM |
11143 | static void __init perf_event_init_all_cpus(void) |
11144 | { | |
b28ab83c | 11145 | struct swevent_htable *swhash; |
220b140b | 11146 | int cpu; |
220b140b | 11147 | |
a63fbed7 TG |
11148 | zalloc_cpumask_var(&perf_online_mask, GFP_KERNEL); |
11149 | ||
220b140b | 11150 | for_each_possible_cpu(cpu) { |
b28ab83c PZ |
11151 | swhash = &per_cpu(swevent_htable, cpu); |
11152 | mutex_init(&swhash->hlist_mutex); | |
2fde4f94 | 11153 | INIT_LIST_HEAD(&per_cpu(active_ctx_list, cpu)); |
f2fb6bef KL |
11154 | |
11155 | INIT_LIST_HEAD(&per_cpu(pmu_sb_events.list, cpu)); | |
11156 | raw_spin_lock_init(&per_cpu(pmu_sb_events.lock, cpu)); | |
e48c1788 | 11157 | |
058fe1c0 DCC |
11158 | #ifdef CONFIG_CGROUP_PERF |
11159 | INIT_LIST_HEAD(&per_cpu(cgrp_cpuctx_list, cpu)); | |
11160 | #endif | |
e48c1788 | 11161 | INIT_LIST_HEAD(&per_cpu(sched_cb_list, cpu)); |
220b140b PM |
11162 | } |
11163 | } | |
11164 | ||
a63fbed7 | 11165 | void perf_swevent_init_cpu(unsigned int cpu) |
0793a61d | 11166 | { |
108b02cf | 11167 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
0793a61d | 11168 | |
b28ab83c | 11169 | mutex_lock(&swhash->hlist_mutex); |
059fcd8c | 11170 | if (swhash->hlist_refcount > 0 && !swevent_hlist_deref(swhash)) { |
76e1d904 FW |
11171 | struct swevent_hlist *hlist; |
11172 | ||
b28ab83c PZ |
11173 | hlist = kzalloc_node(sizeof(*hlist), GFP_KERNEL, cpu_to_node(cpu)); |
11174 | WARN_ON(!hlist); | |
11175 | rcu_assign_pointer(swhash->swevent_hlist, hlist); | |
76e1d904 | 11176 | } |
b28ab83c | 11177 | mutex_unlock(&swhash->hlist_mutex); |
0793a61d TG |
11178 | } |
11179 | ||
2965faa5 | 11180 | #if defined CONFIG_HOTPLUG_CPU || defined CONFIG_KEXEC_CORE |
108b02cf | 11181 | static void __perf_event_exit_context(void *__info) |
0793a61d | 11182 | { |
108b02cf | 11183 | struct perf_event_context *ctx = __info; |
fae3fde6 PZ |
11184 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
11185 | struct perf_event *event; | |
0793a61d | 11186 | |
fae3fde6 | 11187 | raw_spin_lock(&ctx->lock); |
0ee098c9 | 11188 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
fae3fde6 | 11189 | list_for_each_entry(event, &ctx->event_list, event_entry) |
45a0e07a | 11190 | __perf_remove_from_context(event, cpuctx, ctx, (void *)DETACH_GROUP); |
fae3fde6 | 11191 | raw_spin_unlock(&ctx->lock); |
0793a61d | 11192 | } |
108b02cf PZ |
11193 | |
11194 | static void perf_event_exit_cpu_context(int cpu) | |
11195 | { | |
a63fbed7 | 11196 | struct perf_cpu_context *cpuctx; |
108b02cf PZ |
11197 | struct perf_event_context *ctx; |
11198 | struct pmu *pmu; | |
108b02cf | 11199 | |
a63fbed7 TG |
11200 | mutex_lock(&pmus_lock); |
11201 | list_for_each_entry(pmu, &pmus, entry) { | |
11202 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
11203 | ctx = &cpuctx->ctx; | |
108b02cf PZ |
11204 | |
11205 | mutex_lock(&ctx->mutex); | |
11206 | smp_call_function_single(cpu, __perf_event_exit_context, ctx, 1); | |
a63fbed7 | 11207 | cpuctx->online = 0; |
108b02cf PZ |
11208 | mutex_unlock(&ctx->mutex); |
11209 | } | |
a63fbed7 TG |
11210 | cpumask_clear_cpu(cpu, perf_online_mask); |
11211 | mutex_unlock(&pmus_lock); | |
108b02cf | 11212 | } |
00e16c3d TG |
11213 | #else |
11214 | ||
11215 | static void perf_event_exit_cpu_context(int cpu) { } | |
11216 | ||
11217 | #endif | |
108b02cf | 11218 | |
a63fbed7 TG |
11219 | int perf_event_init_cpu(unsigned int cpu) |
11220 | { | |
11221 | struct perf_cpu_context *cpuctx; | |
11222 | struct perf_event_context *ctx; | |
11223 | struct pmu *pmu; | |
11224 | ||
11225 | perf_swevent_init_cpu(cpu); | |
11226 | ||
11227 | mutex_lock(&pmus_lock); | |
11228 | cpumask_set_cpu(cpu, perf_online_mask); | |
11229 | list_for_each_entry(pmu, &pmus, entry) { | |
11230 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
11231 | ctx = &cpuctx->ctx; | |
11232 | ||
11233 | mutex_lock(&ctx->mutex); | |
11234 | cpuctx->online = 1; | |
11235 | mutex_unlock(&ctx->mutex); | |
11236 | } | |
11237 | mutex_unlock(&pmus_lock); | |
11238 | ||
11239 | return 0; | |
11240 | } | |
11241 | ||
00e16c3d | 11242 | int perf_event_exit_cpu(unsigned int cpu) |
0793a61d | 11243 | { |
e3703f8c | 11244 | perf_event_exit_cpu_context(cpu); |
00e16c3d | 11245 | return 0; |
0793a61d | 11246 | } |
0793a61d | 11247 | |
c277443c PZ |
11248 | static int |
11249 | perf_reboot(struct notifier_block *notifier, unsigned long val, void *v) | |
11250 | { | |
11251 | int cpu; | |
11252 | ||
11253 | for_each_online_cpu(cpu) | |
11254 | perf_event_exit_cpu(cpu); | |
11255 | ||
11256 | return NOTIFY_OK; | |
11257 | } | |
11258 | ||
11259 | /* | |
11260 | * Run the perf reboot notifier at the very last possible moment so that | |
11261 | * the generic watchdog code runs as long as possible. | |
11262 | */ | |
11263 | static struct notifier_block perf_reboot_notifier = { | |
11264 | .notifier_call = perf_reboot, | |
11265 | .priority = INT_MIN, | |
11266 | }; | |
11267 | ||
cdd6c482 | 11268 | void __init perf_event_init(void) |
0793a61d | 11269 | { |
3c502e7a JW |
11270 | int ret; |
11271 | ||
2e80a82a PZ |
11272 | idr_init(&pmu_idr); |
11273 | ||
220b140b | 11274 | perf_event_init_all_cpus(); |
b0a873eb | 11275 | init_srcu_struct(&pmus_srcu); |
2e80a82a PZ |
11276 | perf_pmu_register(&perf_swevent, "software", PERF_TYPE_SOFTWARE); |
11277 | perf_pmu_register(&perf_cpu_clock, NULL, -1); | |
11278 | perf_pmu_register(&perf_task_clock, NULL, -1); | |
b0a873eb | 11279 | perf_tp_register(); |
00e16c3d | 11280 | perf_event_init_cpu(smp_processor_id()); |
c277443c | 11281 | register_reboot_notifier(&perf_reboot_notifier); |
3c502e7a JW |
11282 | |
11283 | ret = init_hw_breakpoint(); | |
11284 | WARN(ret, "hw_breakpoint initialization failed with: %d", ret); | |
b2029520 | 11285 | |
b01c3a00 JO |
11286 | /* |
11287 | * Build time assertion that we keep the data_head at the intended | |
11288 | * location. IOW, validation we got the __reserved[] size right. | |
11289 | */ | |
11290 | BUILD_BUG_ON((offsetof(struct perf_event_mmap_page, data_head)) | |
11291 | != 1024); | |
0793a61d | 11292 | } |
abe43400 | 11293 | |
fd979c01 CS |
11294 | ssize_t perf_event_sysfs_show(struct device *dev, struct device_attribute *attr, |
11295 | char *page) | |
11296 | { | |
11297 | struct perf_pmu_events_attr *pmu_attr = | |
11298 | container_of(attr, struct perf_pmu_events_attr, attr); | |
11299 | ||
11300 | if (pmu_attr->event_str) | |
11301 | return sprintf(page, "%s\n", pmu_attr->event_str); | |
11302 | ||
11303 | return 0; | |
11304 | } | |
675965b0 | 11305 | EXPORT_SYMBOL_GPL(perf_event_sysfs_show); |
fd979c01 | 11306 | |
abe43400 PZ |
11307 | static int __init perf_event_sysfs_init(void) |
11308 | { | |
11309 | struct pmu *pmu; | |
11310 | int ret; | |
11311 | ||
11312 | mutex_lock(&pmus_lock); | |
11313 | ||
11314 | ret = bus_register(&pmu_bus); | |
11315 | if (ret) | |
11316 | goto unlock; | |
11317 | ||
11318 | list_for_each_entry(pmu, &pmus, entry) { | |
11319 | if (!pmu->name || pmu->type < 0) | |
11320 | continue; | |
11321 | ||
11322 | ret = pmu_dev_alloc(pmu); | |
11323 | WARN(ret, "Failed to register pmu: %s, reason %d\n", pmu->name, ret); | |
11324 | } | |
11325 | pmu_bus_running = 1; | |
11326 | ret = 0; | |
11327 | ||
11328 | unlock: | |
11329 | mutex_unlock(&pmus_lock); | |
11330 | ||
11331 | return ret; | |
11332 | } | |
11333 | device_initcall(perf_event_sysfs_init); | |
e5d1367f SE |
11334 | |
11335 | #ifdef CONFIG_CGROUP_PERF | |
eb95419b TH |
11336 | static struct cgroup_subsys_state * |
11337 | perf_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) | |
e5d1367f SE |
11338 | { |
11339 | struct perf_cgroup *jc; | |
e5d1367f | 11340 | |
1b15d055 | 11341 | jc = kzalloc(sizeof(*jc), GFP_KERNEL); |
e5d1367f SE |
11342 | if (!jc) |
11343 | return ERR_PTR(-ENOMEM); | |
11344 | ||
e5d1367f SE |
11345 | jc->info = alloc_percpu(struct perf_cgroup_info); |
11346 | if (!jc->info) { | |
11347 | kfree(jc); | |
11348 | return ERR_PTR(-ENOMEM); | |
11349 | } | |
11350 | ||
e5d1367f SE |
11351 | return &jc->css; |
11352 | } | |
11353 | ||
eb95419b | 11354 | static void perf_cgroup_css_free(struct cgroup_subsys_state *css) |
e5d1367f | 11355 | { |
eb95419b TH |
11356 | struct perf_cgroup *jc = container_of(css, struct perf_cgroup, css); |
11357 | ||
e5d1367f SE |
11358 | free_percpu(jc->info); |
11359 | kfree(jc); | |
11360 | } | |
11361 | ||
11362 | static int __perf_cgroup_move(void *info) | |
11363 | { | |
11364 | struct task_struct *task = info; | |
ddaaf4e2 | 11365 | rcu_read_lock(); |
e5d1367f | 11366 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT | PERF_CGROUP_SWIN); |
ddaaf4e2 | 11367 | rcu_read_unlock(); |
e5d1367f SE |
11368 | return 0; |
11369 | } | |
11370 | ||
1f7dd3e5 | 11371 | static void perf_cgroup_attach(struct cgroup_taskset *tset) |
e5d1367f | 11372 | { |
bb9d97b6 | 11373 | struct task_struct *task; |
1f7dd3e5 | 11374 | struct cgroup_subsys_state *css; |
bb9d97b6 | 11375 | |
1f7dd3e5 | 11376 | cgroup_taskset_for_each(task, css, tset) |
bb9d97b6 | 11377 | task_function_call(task, __perf_cgroup_move, task); |
e5d1367f SE |
11378 | } |
11379 | ||
073219e9 | 11380 | struct cgroup_subsys perf_event_cgrp_subsys = { |
92fb9748 TH |
11381 | .css_alloc = perf_cgroup_css_alloc, |
11382 | .css_free = perf_cgroup_css_free, | |
bb9d97b6 | 11383 | .attach = perf_cgroup_attach, |
968ebff1 TH |
11384 | /* |
11385 | * Implicitly enable on dfl hierarchy so that perf events can | |
11386 | * always be filtered by cgroup2 path as long as perf_event | |
11387 | * controller is not mounted on a legacy hierarchy. | |
11388 | */ | |
11389 | .implicit_on_dfl = true, | |
8cfd8147 | 11390 | .threaded = true, |
e5d1367f SE |
11391 | }; |
11392 | #endif /* CONFIG_CGROUP_PERF */ |