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Commit | Line | Data |
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8e86e015 | 1 | // SPDX-License-Identifier: GPL-2.0 |
0793a61d | 2 | /* |
57c0c15b | 3 | * Performance events core code: |
0793a61d | 4 | * |
98144511 | 5 | * Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de> |
e7e7ee2e | 6 | * Copyright (C) 2008-2011 Red Hat, Inc., Ingo Molnar |
90eec103 | 7 | * Copyright (C) 2008-2011 Red Hat, Inc., Peter Zijlstra |
d36b6910 | 8 | * Copyright © 2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com> |
0793a61d TG |
9 | */ |
10 | ||
11 | #include <linux/fs.h> | |
b9cacc7b | 12 | #include <linux/mm.h> |
0793a61d TG |
13 | #include <linux/cpu.h> |
14 | #include <linux/smp.h> | |
2e80a82a | 15 | #include <linux/idr.h> |
04289bb9 | 16 | #include <linux/file.h> |
0793a61d | 17 | #include <linux/poll.h> |
5a0e3ad6 | 18 | #include <linux/slab.h> |
76e1d904 | 19 | #include <linux/hash.h> |
12351ef8 | 20 | #include <linux/tick.h> |
0793a61d | 21 | #include <linux/sysfs.h> |
22a4f650 | 22 | #include <linux/dcache.h> |
0793a61d | 23 | #include <linux/percpu.h> |
22a4f650 | 24 | #include <linux/ptrace.h> |
c277443c | 25 | #include <linux/reboot.h> |
b9cacc7b | 26 | #include <linux/vmstat.h> |
abe43400 | 27 | #include <linux/device.h> |
6e5fdeed | 28 | #include <linux/export.h> |
906010b2 | 29 | #include <linux/vmalloc.h> |
b9cacc7b PZ |
30 | #include <linux/hardirq.h> |
31 | #include <linux/rculist.h> | |
0793a61d TG |
32 | #include <linux/uaccess.h> |
33 | #include <linux/syscalls.h> | |
34 | #include <linux/anon_inodes.h> | |
aa9c4c0f | 35 | #include <linux/kernel_stat.h> |
39bed6cb | 36 | #include <linux/cgroup.h> |
cdd6c482 | 37 | #include <linux/perf_event.h> |
af658dca | 38 | #include <linux/trace_events.h> |
3c502e7a | 39 | #include <linux/hw_breakpoint.h> |
c5ebcedb | 40 | #include <linux/mm_types.h> |
c464c76e | 41 | #include <linux/module.h> |
f972eb63 | 42 | #include <linux/mman.h> |
b3f20785 | 43 | #include <linux/compat.h> |
2541517c AS |
44 | #include <linux/bpf.h> |
45 | #include <linux/filter.h> | |
375637bc AS |
46 | #include <linux/namei.h> |
47 | #include <linux/parser.h> | |
e6017571 | 48 | #include <linux/sched/clock.h> |
6e84f315 | 49 | #include <linux/sched/mm.h> |
e4222673 HB |
50 | #include <linux/proc_ns.h> |
51 | #include <linux/mount.h> | |
6eef8a71 | 52 | #include <linux/min_heap.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; |
76193a94 | 388 | static atomic_t nr_ksymbol_events __read_mostly; |
6ee52e2a | 389 | static atomic_t nr_bpf_events __read_mostly; |
9ee318a7 | 390 | |
108b02cf PZ |
391 | static LIST_HEAD(pmus); |
392 | static DEFINE_MUTEX(pmus_lock); | |
393 | static struct srcu_struct pmus_srcu; | |
a63fbed7 | 394 | static cpumask_var_t perf_online_mask; |
108b02cf | 395 | |
0764771d | 396 | /* |
cdd6c482 | 397 | * perf event paranoia level: |
0fbdea19 IM |
398 | * -1 - not paranoid at all |
399 | * 0 - disallow raw tracepoint access for unpriv | |
cdd6c482 | 400 | * 1 - disallow cpu events for unpriv |
0fbdea19 | 401 | * 2 - disallow kernel profiling for unpriv |
0764771d | 402 | */ |
0161028b | 403 | int sysctl_perf_event_paranoid __read_mostly = 2; |
0764771d | 404 | |
20443384 FW |
405 | /* Minimum for 512 kiB + 1 user control page */ |
406 | int sysctl_perf_event_mlock __read_mostly = 512 + (PAGE_SIZE / 1024); /* 'free' kiB per user */ | |
df58ab24 PZ |
407 | |
408 | /* | |
cdd6c482 | 409 | * max perf event sample rate |
df58ab24 | 410 | */ |
14c63f17 DH |
411 | #define DEFAULT_MAX_SAMPLE_RATE 100000 |
412 | #define DEFAULT_SAMPLE_PERIOD_NS (NSEC_PER_SEC / DEFAULT_MAX_SAMPLE_RATE) | |
413 | #define DEFAULT_CPU_TIME_MAX_PERCENT 25 | |
414 | ||
415 | int sysctl_perf_event_sample_rate __read_mostly = DEFAULT_MAX_SAMPLE_RATE; | |
416 | ||
417 | static int max_samples_per_tick __read_mostly = DIV_ROUND_UP(DEFAULT_MAX_SAMPLE_RATE, HZ); | |
418 | static int perf_sample_period_ns __read_mostly = DEFAULT_SAMPLE_PERIOD_NS; | |
419 | ||
d9494cb4 PZ |
420 | static int perf_sample_allowed_ns __read_mostly = |
421 | DEFAULT_SAMPLE_PERIOD_NS * DEFAULT_CPU_TIME_MAX_PERCENT / 100; | |
14c63f17 | 422 | |
18ab2cd3 | 423 | static void update_perf_cpu_limits(void) |
14c63f17 DH |
424 | { |
425 | u64 tmp = perf_sample_period_ns; | |
426 | ||
427 | tmp *= sysctl_perf_cpu_time_max_percent; | |
91a612ee PZ |
428 | tmp = div_u64(tmp, 100); |
429 | if (!tmp) | |
430 | tmp = 1; | |
431 | ||
432 | WRITE_ONCE(perf_sample_allowed_ns, tmp); | |
14c63f17 | 433 | } |
163ec435 | 434 | |
8d5bce0c | 435 | static bool perf_rotate_context(struct perf_cpu_context *cpuctx); |
9e630205 | 436 | |
163ec435 PZ |
437 | int perf_proc_update_handler(struct ctl_table *table, int write, |
438 | void __user *buffer, size_t *lenp, | |
439 | loff_t *ppos) | |
440 | { | |
1a51c5da SE |
441 | int ret; |
442 | int perf_cpu = sysctl_perf_cpu_time_max_percent; | |
ab7fdefb KL |
443 | /* |
444 | * If throttling is disabled don't allow the write: | |
445 | */ | |
1a51c5da | 446 | if (write && (perf_cpu == 100 || perf_cpu == 0)) |
ab7fdefb KL |
447 | return -EINVAL; |
448 | ||
1a51c5da SE |
449 | ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
450 | if (ret || !write) | |
451 | return ret; | |
452 | ||
163ec435 | 453 | max_samples_per_tick = DIV_ROUND_UP(sysctl_perf_event_sample_rate, HZ); |
14c63f17 DH |
454 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; |
455 | update_perf_cpu_limits(); | |
456 | ||
457 | return 0; | |
458 | } | |
459 | ||
460 | int sysctl_perf_cpu_time_max_percent __read_mostly = DEFAULT_CPU_TIME_MAX_PERCENT; | |
461 | ||
462 | int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write, | |
463 | void __user *buffer, size_t *lenp, | |
464 | loff_t *ppos) | |
465 | { | |
1572e45a | 466 | int ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
14c63f17 DH |
467 | |
468 | if (ret || !write) | |
469 | return ret; | |
470 | ||
b303e7c1 PZ |
471 | if (sysctl_perf_cpu_time_max_percent == 100 || |
472 | sysctl_perf_cpu_time_max_percent == 0) { | |
91a612ee PZ |
473 | printk(KERN_WARNING |
474 | "perf: Dynamic interrupt throttling disabled, can hang your system!\n"); | |
475 | WRITE_ONCE(perf_sample_allowed_ns, 0); | |
476 | } else { | |
477 | update_perf_cpu_limits(); | |
478 | } | |
163ec435 PZ |
479 | |
480 | return 0; | |
481 | } | |
1ccd1549 | 482 | |
14c63f17 DH |
483 | /* |
484 | * perf samples are done in some very critical code paths (NMIs). | |
485 | * If they take too much CPU time, the system can lock up and not | |
486 | * get any real work done. This will drop the sample rate when | |
487 | * we detect that events are taking too long. | |
488 | */ | |
489 | #define NR_ACCUMULATED_SAMPLES 128 | |
d9494cb4 | 490 | static DEFINE_PER_CPU(u64, running_sample_length); |
14c63f17 | 491 | |
91a612ee PZ |
492 | static u64 __report_avg; |
493 | static u64 __report_allowed; | |
494 | ||
6a02ad66 | 495 | static void perf_duration_warn(struct irq_work *w) |
14c63f17 | 496 | { |
0d87d7ec | 497 | printk_ratelimited(KERN_INFO |
91a612ee PZ |
498 | "perf: interrupt took too long (%lld > %lld), lowering " |
499 | "kernel.perf_event_max_sample_rate to %d\n", | |
500 | __report_avg, __report_allowed, | |
501 | sysctl_perf_event_sample_rate); | |
6a02ad66 PZ |
502 | } |
503 | ||
504 | static DEFINE_IRQ_WORK(perf_duration_work, perf_duration_warn); | |
505 | ||
506 | void perf_sample_event_took(u64 sample_len_ns) | |
507 | { | |
91a612ee PZ |
508 | u64 max_len = READ_ONCE(perf_sample_allowed_ns); |
509 | u64 running_len; | |
510 | u64 avg_len; | |
511 | u32 max; | |
14c63f17 | 512 | |
91a612ee | 513 | if (max_len == 0) |
14c63f17 DH |
514 | return; |
515 | ||
91a612ee PZ |
516 | /* Decay the counter by 1 average sample. */ |
517 | running_len = __this_cpu_read(running_sample_length); | |
518 | running_len -= running_len/NR_ACCUMULATED_SAMPLES; | |
519 | running_len += sample_len_ns; | |
520 | __this_cpu_write(running_sample_length, running_len); | |
14c63f17 DH |
521 | |
522 | /* | |
91a612ee PZ |
523 | * Note: this will be biased artifically low until we have |
524 | * seen NR_ACCUMULATED_SAMPLES. Doing it this way keeps us | |
14c63f17 DH |
525 | * from having to maintain a count. |
526 | */ | |
91a612ee PZ |
527 | avg_len = running_len/NR_ACCUMULATED_SAMPLES; |
528 | if (avg_len <= max_len) | |
14c63f17 DH |
529 | return; |
530 | ||
91a612ee PZ |
531 | __report_avg = avg_len; |
532 | __report_allowed = max_len; | |
14c63f17 | 533 | |
91a612ee PZ |
534 | /* |
535 | * Compute a throttle threshold 25% below the current duration. | |
536 | */ | |
537 | avg_len += avg_len / 4; | |
538 | max = (TICK_NSEC / 100) * sysctl_perf_cpu_time_max_percent; | |
539 | if (avg_len < max) | |
540 | max /= (u32)avg_len; | |
541 | else | |
542 | max = 1; | |
14c63f17 | 543 | |
91a612ee PZ |
544 | WRITE_ONCE(perf_sample_allowed_ns, avg_len); |
545 | WRITE_ONCE(max_samples_per_tick, max); | |
546 | ||
547 | sysctl_perf_event_sample_rate = max * HZ; | |
548 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; | |
6a02ad66 | 549 | |
cd578abb | 550 | if (!irq_work_queue(&perf_duration_work)) { |
91a612ee | 551 | early_printk("perf: interrupt took too long (%lld > %lld), lowering " |
cd578abb | 552 | "kernel.perf_event_max_sample_rate to %d\n", |
91a612ee | 553 | __report_avg, __report_allowed, |
cd578abb PZ |
554 | sysctl_perf_event_sample_rate); |
555 | } | |
14c63f17 DH |
556 | } |
557 | ||
cdd6c482 | 558 | static atomic64_t perf_event_id; |
a96bbc16 | 559 | |
0b3fcf17 SE |
560 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, |
561 | enum event_type_t event_type); | |
562 | ||
563 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
564 | enum event_type_t event_type, |
565 | struct task_struct *task); | |
566 | ||
567 | static void update_context_time(struct perf_event_context *ctx); | |
568 | static u64 perf_event_time(struct perf_event *event); | |
0b3fcf17 | 569 | |
cdd6c482 | 570 | void __weak perf_event_print_debug(void) { } |
0793a61d | 571 | |
84c79910 | 572 | extern __weak const char *perf_pmu_name(void) |
0793a61d | 573 | { |
84c79910 | 574 | return "pmu"; |
0793a61d TG |
575 | } |
576 | ||
0b3fcf17 SE |
577 | static inline u64 perf_clock(void) |
578 | { | |
579 | return local_clock(); | |
580 | } | |
581 | ||
34f43927 PZ |
582 | static inline u64 perf_event_clock(struct perf_event *event) |
583 | { | |
584 | return event->clock(); | |
585 | } | |
586 | ||
0d3d73aa PZ |
587 | /* |
588 | * State based event timekeeping... | |
589 | * | |
590 | * The basic idea is to use event->state to determine which (if any) time | |
591 | * fields to increment with the current delta. This means we only need to | |
592 | * update timestamps when we change state or when they are explicitly requested | |
593 | * (read). | |
594 | * | |
595 | * Event groups make things a little more complicated, but not terribly so. The | |
596 | * rules for a group are that if the group leader is OFF the entire group is | |
597 | * OFF, irrespecive of what the group member states are. This results in | |
598 | * __perf_effective_state(). | |
599 | * | |
600 | * A futher ramification is that when a group leader flips between OFF and | |
601 | * !OFF, we need to update all group member times. | |
602 | * | |
603 | * | |
604 | * NOTE: perf_event_time() is based on the (cgroup) context time, and thus we | |
605 | * need to make sure the relevant context time is updated before we try and | |
606 | * update our timestamps. | |
607 | */ | |
608 | ||
609 | static __always_inline enum perf_event_state | |
610 | __perf_effective_state(struct perf_event *event) | |
611 | { | |
612 | struct perf_event *leader = event->group_leader; | |
613 | ||
614 | if (leader->state <= PERF_EVENT_STATE_OFF) | |
615 | return leader->state; | |
616 | ||
617 | return event->state; | |
618 | } | |
619 | ||
620 | static __always_inline void | |
621 | __perf_update_times(struct perf_event *event, u64 now, u64 *enabled, u64 *running) | |
622 | { | |
623 | enum perf_event_state state = __perf_effective_state(event); | |
624 | u64 delta = now - event->tstamp; | |
625 | ||
626 | *enabled = event->total_time_enabled; | |
627 | if (state >= PERF_EVENT_STATE_INACTIVE) | |
628 | *enabled += delta; | |
629 | ||
630 | *running = event->total_time_running; | |
631 | if (state >= PERF_EVENT_STATE_ACTIVE) | |
632 | *running += delta; | |
633 | } | |
634 | ||
635 | static void perf_event_update_time(struct perf_event *event) | |
636 | { | |
637 | u64 now = perf_event_time(event); | |
638 | ||
639 | __perf_update_times(event, now, &event->total_time_enabled, | |
640 | &event->total_time_running); | |
641 | event->tstamp = now; | |
642 | } | |
643 | ||
644 | static void perf_event_update_sibling_time(struct perf_event *leader) | |
645 | { | |
646 | struct perf_event *sibling; | |
647 | ||
edb39592 | 648 | for_each_sibling_event(sibling, leader) |
0d3d73aa PZ |
649 | perf_event_update_time(sibling); |
650 | } | |
651 | ||
652 | static void | |
653 | perf_event_set_state(struct perf_event *event, enum perf_event_state state) | |
654 | { | |
655 | if (event->state == state) | |
656 | return; | |
657 | ||
658 | perf_event_update_time(event); | |
659 | /* | |
660 | * If a group leader gets enabled/disabled all its siblings | |
661 | * are affected too. | |
662 | */ | |
663 | if ((event->state < 0) ^ (state < 0)) | |
664 | perf_event_update_sibling_time(event); | |
665 | ||
666 | WRITE_ONCE(event->state, state); | |
667 | } | |
668 | ||
e5d1367f SE |
669 | #ifdef CONFIG_CGROUP_PERF |
670 | ||
e5d1367f SE |
671 | static inline bool |
672 | perf_cgroup_match(struct perf_event *event) | |
673 | { | |
674 | struct perf_event_context *ctx = event->ctx; | |
675 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
676 | ||
ef824fa1 TH |
677 | /* @event doesn't care about cgroup */ |
678 | if (!event->cgrp) | |
679 | return true; | |
680 | ||
681 | /* wants specific cgroup scope but @cpuctx isn't associated with any */ | |
682 | if (!cpuctx->cgrp) | |
683 | return false; | |
684 | ||
685 | /* | |
686 | * Cgroup scoping is recursive. An event enabled for a cgroup is | |
687 | * also enabled for all its descendant cgroups. If @cpuctx's | |
688 | * cgroup is a descendant of @event's (the test covers identity | |
689 | * case), it's a match. | |
690 | */ | |
691 | return cgroup_is_descendant(cpuctx->cgrp->css.cgroup, | |
692 | event->cgrp->css.cgroup); | |
e5d1367f SE |
693 | } |
694 | ||
e5d1367f SE |
695 | static inline void perf_detach_cgroup(struct perf_event *event) |
696 | { | |
4e2ba650 | 697 | css_put(&event->cgrp->css); |
e5d1367f SE |
698 | event->cgrp = NULL; |
699 | } | |
700 | ||
701 | static inline int is_cgroup_event(struct perf_event *event) | |
702 | { | |
703 | return event->cgrp != NULL; | |
704 | } | |
705 | ||
706 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
707 | { | |
708 | struct perf_cgroup_info *t; | |
709 | ||
710 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
711 | return t->time; | |
712 | } | |
713 | ||
714 | static inline void __update_cgrp_time(struct perf_cgroup *cgrp) | |
715 | { | |
716 | struct perf_cgroup_info *info; | |
717 | u64 now; | |
718 | ||
719 | now = perf_clock(); | |
720 | ||
721 | info = this_cpu_ptr(cgrp->info); | |
722 | ||
723 | info->time += now - info->timestamp; | |
724 | info->timestamp = now; | |
725 | } | |
726 | ||
727 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
728 | { | |
c917e0f2 SL |
729 | struct perf_cgroup *cgrp = cpuctx->cgrp; |
730 | struct cgroup_subsys_state *css; | |
731 | ||
732 | if (cgrp) { | |
733 | for (css = &cgrp->css; css; css = css->parent) { | |
734 | cgrp = container_of(css, struct perf_cgroup, css); | |
735 | __update_cgrp_time(cgrp); | |
736 | } | |
737 | } | |
e5d1367f SE |
738 | } |
739 | ||
740 | static inline void update_cgrp_time_from_event(struct perf_event *event) | |
741 | { | |
3f7cce3c SE |
742 | struct perf_cgroup *cgrp; |
743 | ||
e5d1367f | 744 | /* |
3f7cce3c SE |
745 | * ensure we access cgroup data only when needed and |
746 | * when we know the cgroup is pinned (css_get) | |
e5d1367f | 747 | */ |
3f7cce3c | 748 | if (!is_cgroup_event(event)) |
e5d1367f SE |
749 | return; |
750 | ||
614e4c4e | 751 | cgrp = perf_cgroup_from_task(current, event->ctx); |
3f7cce3c SE |
752 | /* |
753 | * Do not update time when cgroup is not active | |
754 | */ | |
28fa741c | 755 | if (cgroup_is_descendant(cgrp->css.cgroup, event->cgrp->css.cgroup)) |
3f7cce3c | 756 | __update_cgrp_time(event->cgrp); |
e5d1367f SE |
757 | } |
758 | ||
759 | static inline void | |
3f7cce3c SE |
760 | perf_cgroup_set_timestamp(struct task_struct *task, |
761 | struct perf_event_context *ctx) | |
e5d1367f SE |
762 | { |
763 | struct perf_cgroup *cgrp; | |
764 | struct perf_cgroup_info *info; | |
c917e0f2 | 765 | struct cgroup_subsys_state *css; |
e5d1367f | 766 | |
3f7cce3c SE |
767 | /* |
768 | * ctx->lock held by caller | |
769 | * ensure we do not access cgroup data | |
770 | * unless we have the cgroup pinned (css_get) | |
771 | */ | |
772 | if (!task || !ctx->nr_cgroups) | |
e5d1367f SE |
773 | return; |
774 | ||
614e4c4e | 775 | cgrp = perf_cgroup_from_task(task, ctx); |
c917e0f2 SL |
776 | |
777 | for (css = &cgrp->css; css; css = css->parent) { | |
778 | cgrp = container_of(css, struct perf_cgroup, css); | |
779 | info = this_cpu_ptr(cgrp->info); | |
780 | info->timestamp = ctx->timestamp; | |
781 | } | |
e5d1367f SE |
782 | } |
783 | ||
058fe1c0 DCC |
784 | static DEFINE_PER_CPU(struct list_head, cgrp_cpuctx_list); |
785 | ||
e5d1367f SE |
786 | #define PERF_CGROUP_SWOUT 0x1 /* cgroup switch out every event */ |
787 | #define PERF_CGROUP_SWIN 0x2 /* cgroup switch in events based on task */ | |
788 | ||
789 | /* | |
790 | * reschedule events based on the cgroup constraint of task. | |
791 | * | |
792 | * mode SWOUT : schedule out everything | |
793 | * mode SWIN : schedule in based on cgroup for next | |
794 | */ | |
18ab2cd3 | 795 | static void perf_cgroup_switch(struct task_struct *task, int mode) |
e5d1367f SE |
796 | { |
797 | struct perf_cpu_context *cpuctx; | |
058fe1c0 | 798 | struct list_head *list; |
e5d1367f SE |
799 | unsigned long flags; |
800 | ||
801 | /* | |
058fe1c0 DCC |
802 | * Disable interrupts and preemption to avoid this CPU's |
803 | * cgrp_cpuctx_entry to change under us. | |
e5d1367f SE |
804 | */ |
805 | local_irq_save(flags); | |
806 | ||
058fe1c0 DCC |
807 | list = this_cpu_ptr(&cgrp_cpuctx_list); |
808 | list_for_each_entry(cpuctx, list, cgrp_cpuctx_entry) { | |
809 | WARN_ON_ONCE(cpuctx->ctx.nr_cgroups == 0); | |
e5d1367f | 810 | |
058fe1c0 DCC |
811 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
812 | perf_pmu_disable(cpuctx->ctx.pmu); | |
e5d1367f | 813 | |
058fe1c0 DCC |
814 | if (mode & PERF_CGROUP_SWOUT) { |
815 | cpu_ctx_sched_out(cpuctx, EVENT_ALL); | |
816 | /* | |
817 | * must not be done before ctxswout due | |
818 | * to event_filter_match() in event_sched_out() | |
819 | */ | |
820 | cpuctx->cgrp = NULL; | |
821 | } | |
e5d1367f | 822 | |
058fe1c0 DCC |
823 | if (mode & PERF_CGROUP_SWIN) { |
824 | WARN_ON_ONCE(cpuctx->cgrp); | |
825 | /* | |
826 | * set cgrp before ctxsw in to allow | |
827 | * event_filter_match() to not have to pass | |
828 | * task around | |
829 | * we pass the cpuctx->ctx to perf_cgroup_from_task() | |
830 | * because cgorup events are only per-cpu | |
831 | */ | |
832 | cpuctx->cgrp = perf_cgroup_from_task(task, | |
833 | &cpuctx->ctx); | |
834 | cpu_ctx_sched_in(cpuctx, EVENT_ALL, task); | |
e5d1367f | 835 | } |
058fe1c0 DCC |
836 | perf_pmu_enable(cpuctx->ctx.pmu); |
837 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
e5d1367f SE |
838 | } |
839 | ||
e5d1367f SE |
840 | local_irq_restore(flags); |
841 | } | |
842 | ||
a8d757ef SE |
843 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
844 | struct task_struct *next) | |
e5d1367f | 845 | { |
a8d757ef SE |
846 | struct perf_cgroup *cgrp1; |
847 | struct perf_cgroup *cgrp2 = NULL; | |
848 | ||
ddaaf4e2 | 849 | rcu_read_lock(); |
a8d757ef SE |
850 | /* |
851 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
852 | * we do not need to pass the ctx here because we know |
853 | * we are holding the rcu lock | |
a8d757ef | 854 | */ |
614e4c4e | 855 | cgrp1 = perf_cgroup_from_task(task, NULL); |
70a01657 | 856 | cgrp2 = perf_cgroup_from_task(next, NULL); |
a8d757ef SE |
857 | |
858 | /* | |
859 | * only schedule out current cgroup events if we know | |
860 | * that we are switching to a different cgroup. Otherwise, | |
861 | * do no touch the cgroup events. | |
862 | */ | |
863 | if (cgrp1 != cgrp2) | |
864 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT); | |
ddaaf4e2 SE |
865 | |
866 | rcu_read_unlock(); | |
e5d1367f SE |
867 | } |
868 | ||
a8d757ef SE |
869 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
870 | struct task_struct *task) | |
e5d1367f | 871 | { |
a8d757ef SE |
872 | struct perf_cgroup *cgrp1; |
873 | struct perf_cgroup *cgrp2 = NULL; | |
874 | ||
ddaaf4e2 | 875 | rcu_read_lock(); |
a8d757ef SE |
876 | /* |
877 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
878 | * we do not need to pass the ctx here because we know |
879 | * we are holding the rcu lock | |
a8d757ef | 880 | */ |
614e4c4e | 881 | cgrp1 = perf_cgroup_from_task(task, NULL); |
614e4c4e | 882 | cgrp2 = perf_cgroup_from_task(prev, NULL); |
a8d757ef SE |
883 | |
884 | /* | |
885 | * only need to schedule in cgroup events if we are changing | |
886 | * cgroup during ctxsw. Cgroup events were not scheduled | |
887 | * out of ctxsw out if that was not the case. | |
888 | */ | |
889 | if (cgrp1 != cgrp2) | |
890 | perf_cgroup_switch(task, PERF_CGROUP_SWIN); | |
ddaaf4e2 SE |
891 | |
892 | rcu_read_unlock(); | |
e5d1367f SE |
893 | } |
894 | ||
c2283c93 IR |
895 | static int perf_cgroup_ensure_storage(struct perf_event *event, |
896 | struct cgroup_subsys_state *css) | |
897 | { | |
898 | struct perf_cpu_context *cpuctx; | |
899 | struct perf_event **storage; | |
900 | int cpu, heap_size, ret = 0; | |
901 | ||
902 | /* | |
903 | * Allow storage to have sufficent space for an iterator for each | |
904 | * possibly nested cgroup plus an iterator for events with no cgroup. | |
905 | */ | |
906 | for (heap_size = 1; css; css = css->parent) | |
907 | heap_size++; | |
908 | ||
909 | for_each_possible_cpu(cpu) { | |
910 | cpuctx = per_cpu_ptr(event->pmu->pmu_cpu_context, cpu); | |
911 | if (heap_size <= cpuctx->heap_size) | |
912 | continue; | |
913 | ||
914 | storage = kmalloc_node(heap_size * sizeof(struct perf_event *), | |
915 | GFP_KERNEL, cpu_to_node(cpu)); | |
916 | if (!storage) { | |
917 | ret = -ENOMEM; | |
918 | break; | |
919 | } | |
920 | ||
921 | raw_spin_lock_irq(&cpuctx->ctx.lock); | |
922 | if (cpuctx->heap_size < heap_size) { | |
923 | swap(cpuctx->heap, storage); | |
924 | if (storage == cpuctx->heap_default) | |
925 | storage = NULL; | |
926 | cpuctx->heap_size = heap_size; | |
927 | } | |
928 | raw_spin_unlock_irq(&cpuctx->ctx.lock); | |
929 | ||
930 | kfree(storage); | |
931 | } | |
932 | ||
933 | return ret; | |
934 | } | |
935 | ||
e5d1367f SE |
936 | static inline int perf_cgroup_connect(int fd, struct perf_event *event, |
937 | struct perf_event_attr *attr, | |
938 | struct perf_event *group_leader) | |
939 | { | |
940 | struct perf_cgroup *cgrp; | |
941 | struct cgroup_subsys_state *css; | |
2903ff01 AV |
942 | struct fd f = fdget(fd); |
943 | int ret = 0; | |
e5d1367f | 944 | |
2903ff01 | 945 | if (!f.file) |
e5d1367f SE |
946 | return -EBADF; |
947 | ||
b583043e | 948 | css = css_tryget_online_from_dir(f.file->f_path.dentry, |
ec903c0c | 949 | &perf_event_cgrp_subsys); |
3db272c0 LZ |
950 | if (IS_ERR(css)) { |
951 | ret = PTR_ERR(css); | |
952 | goto out; | |
953 | } | |
e5d1367f | 954 | |
c2283c93 IR |
955 | ret = perf_cgroup_ensure_storage(event, css); |
956 | if (ret) | |
957 | goto out; | |
958 | ||
e5d1367f SE |
959 | cgrp = container_of(css, struct perf_cgroup, css); |
960 | event->cgrp = cgrp; | |
961 | ||
962 | /* | |
963 | * all events in a group must monitor | |
964 | * the same cgroup because a task belongs | |
965 | * to only one perf cgroup at a time | |
966 | */ | |
967 | if (group_leader && group_leader->cgrp != cgrp) { | |
968 | perf_detach_cgroup(event); | |
969 | ret = -EINVAL; | |
e5d1367f | 970 | } |
3db272c0 | 971 | out: |
2903ff01 | 972 | fdput(f); |
e5d1367f SE |
973 | return ret; |
974 | } | |
975 | ||
976 | static inline void | |
977 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
978 | { | |
979 | struct perf_cgroup_info *t; | |
980 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
981 | event->shadow_ctx_time = now - t->timestamp; | |
982 | } | |
983 | ||
db4a8356 DCC |
984 | /* |
985 | * Update cpuctx->cgrp so that it is set when first cgroup event is added and | |
986 | * cleared when last cgroup event is removed. | |
987 | */ | |
988 | static inline void | |
989 | list_update_cgroup_event(struct perf_event *event, | |
990 | struct perf_event_context *ctx, bool add) | |
991 | { | |
992 | struct perf_cpu_context *cpuctx; | |
058fe1c0 | 993 | struct list_head *cpuctx_entry; |
db4a8356 DCC |
994 | |
995 | if (!is_cgroup_event(event)) | |
996 | return; | |
997 | ||
db4a8356 DCC |
998 | /* |
999 | * Because cgroup events are always per-cpu events, | |
07c59729 | 1000 | * @ctx == &cpuctx->ctx. |
db4a8356 | 1001 | */ |
07c59729 | 1002 | cpuctx = container_of(ctx, struct perf_cpu_context, ctx); |
33801b94 | 1003 | |
1004 | /* | |
1005 | * Since setting cpuctx->cgrp is conditional on the current @cgrp | |
1006 | * matching the event's cgroup, we must do this for every new event, | |
1007 | * because if the first would mismatch, the second would not try again | |
1008 | * and we would leave cpuctx->cgrp unset. | |
1009 | */ | |
1010 | if (add && !cpuctx->cgrp) { | |
be96b316 TH |
1011 | struct perf_cgroup *cgrp = perf_cgroup_from_task(current, ctx); |
1012 | ||
be96b316 TH |
1013 | if (cgroup_is_descendant(cgrp->css.cgroup, event->cgrp->css.cgroup)) |
1014 | cpuctx->cgrp = cgrp; | |
058fe1c0 | 1015 | } |
33801b94 | 1016 | |
1017 | if (add && ctx->nr_cgroups++) | |
1018 | return; | |
1019 | else if (!add && --ctx->nr_cgroups) | |
1020 | return; | |
1021 | ||
1022 | /* no cgroup running */ | |
1023 | if (!add) | |
1024 | cpuctx->cgrp = NULL; | |
1025 | ||
1026 | cpuctx_entry = &cpuctx->cgrp_cpuctx_entry; | |
1027 | if (add) | |
07c59729 SL |
1028 | list_add(cpuctx_entry, |
1029 | per_cpu_ptr(&cgrp_cpuctx_list, event->cpu)); | |
33801b94 | 1030 | else |
1031 | list_del(cpuctx_entry); | |
db4a8356 DCC |
1032 | } |
1033 | ||
e5d1367f SE |
1034 | #else /* !CONFIG_CGROUP_PERF */ |
1035 | ||
1036 | static inline bool | |
1037 | perf_cgroup_match(struct perf_event *event) | |
1038 | { | |
1039 | return true; | |
1040 | } | |
1041 | ||
1042 | static inline void perf_detach_cgroup(struct perf_event *event) | |
1043 | {} | |
1044 | ||
1045 | static inline int is_cgroup_event(struct perf_event *event) | |
1046 | { | |
1047 | return 0; | |
1048 | } | |
1049 | ||
e5d1367f SE |
1050 | static inline void update_cgrp_time_from_event(struct perf_event *event) |
1051 | { | |
1052 | } | |
1053 | ||
1054 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
1055 | { | |
1056 | } | |
1057 | ||
a8d757ef SE |
1058 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
1059 | struct task_struct *next) | |
e5d1367f SE |
1060 | { |
1061 | } | |
1062 | ||
a8d757ef SE |
1063 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
1064 | struct task_struct *task) | |
e5d1367f SE |
1065 | { |
1066 | } | |
1067 | ||
1068 | static inline int perf_cgroup_connect(pid_t pid, struct perf_event *event, | |
1069 | struct perf_event_attr *attr, | |
1070 | struct perf_event *group_leader) | |
1071 | { | |
1072 | return -EINVAL; | |
1073 | } | |
1074 | ||
1075 | static inline void | |
3f7cce3c SE |
1076 | perf_cgroup_set_timestamp(struct task_struct *task, |
1077 | struct perf_event_context *ctx) | |
e5d1367f SE |
1078 | { |
1079 | } | |
1080 | ||
d00dbd29 | 1081 | static inline void |
e5d1367f SE |
1082 | perf_cgroup_switch(struct task_struct *task, struct task_struct *next) |
1083 | { | |
1084 | } | |
1085 | ||
1086 | static inline void | |
1087 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
1088 | { | |
1089 | } | |
1090 | ||
1091 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
1092 | { | |
1093 | return 0; | |
1094 | } | |
1095 | ||
db4a8356 DCC |
1096 | static inline void |
1097 | list_update_cgroup_event(struct perf_event *event, | |
1098 | struct perf_event_context *ctx, bool add) | |
1099 | { | |
1100 | } | |
1101 | ||
e5d1367f SE |
1102 | #endif |
1103 | ||
9e630205 SE |
1104 | /* |
1105 | * set default to be dependent on timer tick just | |
1106 | * like original code | |
1107 | */ | |
1108 | #define PERF_CPU_HRTIMER (1000 / HZ) | |
1109 | /* | |
8a1115ff | 1110 | * function must be called with interrupts disabled |
9e630205 | 1111 | */ |
272325c4 | 1112 | static enum hrtimer_restart perf_mux_hrtimer_handler(struct hrtimer *hr) |
9e630205 SE |
1113 | { |
1114 | struct perf_cpu_context *cpuctx; | |
8d5bce0c | 1115 | bool rotations; |
9e630205 | 1116 | |
16444645 | 1117 | lockdep_assert_irqs_disabled(); |
9e630205 SE |
1118 | |
1119 | cpuctx = container_of(hr, struct perf_cpu_context, hrtimer); | |
9e630205 SE |
1120 | rotations = perf_rotate_context(cpuctx); |
1121 | ||
4cfafd30 PZ |
1122 | raw_spin_lock(&cpuctx->hrtimer_lock); |
1123 | if (rotations) | |
9e630205 | 1124 | hrtimer_forward_now(hr, cpuctx->hrtimer_interval); |
4cfafd30 PZ |
1125 | else |
1126 | cpuctx->hrtimer_active = 0; | |
1127 | raw_spin_unlock(&cpuctx->hrtimer_lock); | |
9e630205 | 1128 | |
4cfafd30 | 1129 | return rotations ? HRTIMER_RESTART : HRTIMER_NORESTART; |
9e630205 SE |
1130 | } |
1131 | ||
272325c4 | 1132 | static void __perf_mux_hrtimer_init(struct perf_cpu_context *cpuctx, int cpu) |
9e630205 | 1133 | { |
272325c4 | 1134 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1135 | struct pmu *pmu = cpuctx->ctx.pmu; |
272325c4 | 1136 | u64 interval; |
9e630205 SE |
1137 | |
1138 | /* no multiplexing needed for SW PMU */ | |
1139 | if (pmu->task_ctx_nr == perf_sw_context) | |
1140 | return; | |
1141 | ||
62b85639 SE |
1142 | /* |
1143 | * check default is sane, if not set then force to | |
1144 | * default interval (1/tick) | |
1145 | */ | |
272325c4 PZ |
1146 | interval = pmu->hrtimer_interval_ms; |
1147 | if (interval < 1) | |
1148 | interval = pmu->hrtimer_interval_ms = PERF_CPU_HRTIMER; | |
62b85639 | 1149 | |
272325c4 | 1150 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * interval); |
9e630205 | 1151 | |
4cfafd30 | 1152 | raw_spin_lock_init(&cpuctx->hrtimer_lock); |
30f9028b | 1153 | hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_PINNED_HARD); |
272325c4 | 1154 | timer->function = perf_mux_hrtimer_handler; |
9e630205 SE |
1155 | } |
1156 | ||
272325c4 | 1157 | static int perf_mux_hrtimer_restart(struct perf_cpu_context *cpuctx) |
9e630205 | 1158 | { |
272325c4 | 1159 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1160 | struct pmu *pmu = cpuctx->ctx.pmu; |
4cfafd30 | 1161 | unsigned long flags; |
9e630205 SE |
1162 | |
1163 | /* not for SW PMU */ | |
1164 | if (pmu->task_ctx_nr == perf_sw_context) | |
272325c4 | 1165 | return 0; |
9e630205 | 1166 | |
4cfafd30 PZ |
1167 | raw_spin_lock_irqsave(&cpuctx->hrtimer_lock, flags); |
1168 | if (!cpuctx->hrtimer_active) { | |
1169 | cpuctx->hrtimer_active = 1; | |
1170 | hrtimer_forward_now(timer, cpuctx->hrtimer_interval); | |
30f9028b | 1171 | hrtimer_start_expires(timer, HRTIMER_MODE_ABS_PINNED_HARD); |
4cfafd30 PZ |
1172 | } |
1173 | raw_spin_unlock_irqrestore(&cpuctx->hrtimer_lock, flags); | |
9e630205 | 1174 | |
272325c4 | 1175 | return 0; |
9e630205 SE |
1176 | } |
1177 | ||
33696fc0 | 1178 | void perf_pmu_disable(struct pmu *pmu) |
9e35ad38 | 1179 | { |
33696fc0 PZ |
1180 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1181 | if (!(*count)++) | |
1182 | pmu->pmu_disable(pmu); | |
9e35ad38 | 1183 | } |
9e35ad38 | 1184 | |
33696fc0 | 1185 | void perf_pmu_enable(struct pmu *pmu) |
9e35ad38 | 1186 | { |
33696fc0 PZ |
1187 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1188 | if (!--(*count)) | |
1189 | pmu->pmu_enable(pmu); | |
9e35ad38 | 1190 | } |
9e35ad38 | 1191 | |
2fde4f94 | 1192 | static DEFINE_PER_CPU(struct list_head, active_ctx_list); |
e9d2b064 PZ |
1193 | |
1194 | /* | |
2fde4f94 MR |
1195 | * perf_event_ctx_activate(), perf_event_ctx_deactivate(), and |
1196 | * perf_event_task_tick() are fully serialized because they're strictly cpu | |
1197 | * affine and perf_event_ctx{activate,deactivate} are called with IRQs | |
1198 | * disabled, while perf_event_task_tick is called from IRQ context. | |
e9d2b064 | 1199 | */ |
2fde4f94 | 1200 | static void perf_event_ctx_activate(struct perf_event_context *ctx) |
9e35ad38 | 1201 | { |
2fde4f94 | 1202 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
b5ab4cd5 | 1203 | |
16444645 | 1204 | lockdep_assert_irqs_disabled(); |
b5ab4cd5 | 1205 | |
2fde4f94 MR |
1206 | WARN_ON(!list_empty(&ctx->active_ctx_list)); |
1207 | ||
1208 | list_add(&ctx->active_ctx_list, head); | |
1209 | } | |
1210 | ||
1211 | static void perf_event_ctx_deactivate(struct perf_event_context *ctx) | |
1212 | { | |
16444645 | 1213 | lockdep_assert_irqs_disabled(); |
2fde4f94 MR |
1214 | |
1215 | WARN_ON(list_empty(&ctx->active_ctx_list)); | |
1216 | ||
1217 | list_del_init(&ctx->active_ctx_list); | |
9e35ad38 | 1218 | } |
9e35ad38 | 1219 | |
cdd6c482 | 1220 | static void get_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1221 | { |
8c94abbb | 1222 | refcount_inc(&ctx->refcount); |
a63eaf34 PM |
1223 | } |
1224 | ||
4af57ef2 YZ |
1225 | static void free_ctx(struct rcu_head *head) |
1226 | { | |
1227 | struct perf_event_context *ctx; | |
1228 | ||
1229 | ctx = container_of(head, struct perf_event_context, rcu_head); | |
1230 | kfree(ctx->task_ctx_data); | |
1231 | kfree(ctx); | |
1232 | } | |
1233 | ||
cdd6c482 | 1234 | static void put_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1235 | { |
8c94abbb | 1236 | if (refcount_dec_and_test(&ctx->refcount)) { |
564c2b21 PM |
1237 | if (ctx->parent_ctx) |
1238 | put_ctx(ctx->parent_ctx); | |
63b6da39 | 1239 | if (ctx->task && ctx->task != TASK_TOMBSTONE) |
c93f7669 | 1240 | put_task_struct(ctx->task); |
4af57ef2 | 1241 | call_rcu(&ctx->rcu_head, free_ctx); |
564c2b21 | 1242 | } |
a63eaf34 PM |
1243 | } |
1244 | ||
f63a8daa PZ |
1245 | /* |
1246 | * Because of perf_event::ctx migration in sys_perf_event_open::move_group and | |
1247 | * perf_pmu_migrate_context() we need some magic. | |
1248 | * | |
1249 | * Those places that change perf_event::ctx will hold both | |
1250 | * perf_event_ctx::mutex of the 'old' and 'new' ctx value. | |
1251 | * | |
8b10c5e2 PZ |
1252 | * Lock ordering is by mutex address. There are two other sites where |
1253 | * perf_event_context::mutex nests and those are: | |
1254 | * | |
1255 | * - perf_event_exit_task_context() [ child , 0 ] | |
8ba289b8 PZ |
1256 | * perf_event_exit_event() |
1257 | * put_event() [ parent, 1 ] | |
8b10c5e2 PZ |
1258 | * |
1259 | * - perf_event_init_context() [ parent, 0 ] | |
1260 | * inherit_task_group() | |
1261 | * inherit_group() | |
1262 | * inherit_event() | |
1263 | * perf_event_alloc() | |
1264 | * perf_init_event() | |
1265 | * perf_try_init_event() [ child , 1 ] | |
1266 | * | |
1267 | * While it appears there is an obvious deadlock here -- the parent and child | |
1268 | * nesting levels are inverted between the two. This is in fact safe because | |
1269 | * life-time rules separate them. That is an exiting task cannot fork, and a | |
1270 | * spawning task cannot (yet) exit. | |
1271 | * | |
1272 | * But remember that that these are parent<->child context relations, and | |
1273 | * migration does not affect children, therefore these two orderings should not | |
1274 | * interact. | |
f63a8daa PZ |
1275 | * |
1276 | * The change in perf_event::ctx does not affect children (as claimed above) | |
1277 | * because the sys_perf_event_open() case will install a new event and break | |
1278 | * the ctx parent<->child relation, and perf_pmu_migrate_context() is only | |
1279 | * concerned with cpuctx and that doesn't have children. | |
1280 | * | |
1281 | * The places that change perf_event::ctx will issue: | |
1282 | * | |
1283 | * perf_remove_from_context(); | |
1284 | * synchronize_rcu(); | |
1285 | * perf_install_in_context(); | |
1286 | * | |
1287 | * to affect the change. The remove_from_context() + synchronize_rcu() should | |
1288 | * quiesce the event, after which we can install it in the new location. This | |
1289 | * means that only external vectors (perf_fops, prctl) can perturb the event | |
1290 | * while in transit. Therefore all such accessors should also acquire | |
1291 | * perf_event_context::mutex to serialize against this. | |
1292 | * | |
1293 | * However; because event->ctx can change while we're waiting to acquire | |
1294 | * ctx->mutex we must be careful and use the below perf_event_ctx_lock() | |
1295 | * function. | |
1296 | * | |
1297 | * Lock order: | |
79c9ce57 | 1298 | * cred_guard_mutex |
f63a8daa PZ |
1299 | * task_struct::perf_event_mutex |
1300 | * perf_event_context::mutex | |
f63a8daa | 1301 | * perf_event::child_mutex; |
07c4a776 | 1302 | * perf_event_context::lock |
f63a8daa PZ |
1303 | * perf_event::mmap_mutex |
1304 | * mmap_sem | |
18736eef | 1305 | * perf_addr_filters_head::lock |
82d94856 PZ |
1306 | * |
1307 | * cpu_hotplug_lock | |
1308 | * pmus_lock | |
1309 | * cpuctx->mutex / perf_event_context::mutex | |
f63a8daa | 1310 | */ |
a83fe28e PZ |
1311 | static struct perf_event_context * |
1312 | perf_event_ctx_lock_nested(struct perf_event *event, int nesting) | |
f63a8daa PZ |
1313 | { |
1314 | struct perf_event_context *ctx; | |
1315 | ||
1316 | again: | |
1317 | rcu_read_lock(); | |
6aa7de05 | 1318 | ctx = READ_ONCE(event->ctx); |
8c94abbb | 1319 | if (!refcount_inc_not_zero(&ctx->refcount)) { |
f63a8daa PZ |
1320 | rcu_read_unlock(); |
1321 | goto again; | |
1322 | } | |
1323 | rcu_read_unlock(); | |
1324 | ||
a83fe28e | 1325 | mutex_lock_nested(&ctx->mutex, nesting); |
f63a8daa PZ |
1326 | if (event->ctx != ctx) { |
1327 | mutex_unlock(&ctx->mutex); | |
1328 | put_ctx(ctx); | |
1329 | goto again; | |
1330 | } | |
1331 | ||
1332 | return ctx; | |
1333 | } | |
1334 | ||
a83fe28e PZ |
1335 | static inline struct perf_event_context * |
1336 | perf_event_ctx_lock(struct perf_event *event) | |
1337 | { | |
1338 | return perf_event_ctx_lock_nested(event, 0); | |
1339 | } | |
1340 | ||
f63a8daa PZ |
1341 | static void perf_event_ctx_unlock(struct perf_event *event, |
1342 | struct perf_event_context *ctx) | |
1343 | { | |
1344 | mutex_unlock(&ctx->mutex); | |
1345 | put_ctx(ctx); | |
1346 | } | |
1347 | ||
211de6eb PZ |
1348 | /* |
1349 | * This must be done under the ctx->lock, such as to serialize against | |
1350 | * context_equiv(), therefore we cannot call put_ctx() since that might end up | |
1351 | * calling scheduler related locks and ctx->lock nests inside those. | |
1352 | */ | |
1353 | static __must_check struct perf_event_context * | |
1354 | unclone_ctx(struct perf_event_context *ctx) | |
71a851b4 | 1355 | { |
211de6eb PZ |
1356 | struct perf_event_context *parent_ctx = ctx->parent_ctx; |
1357 | ||
1358 | lockdep_assert_held(&ctx->lock); | |
1359 | ||
1360 | if (parent_ctx) | |
71a851b4 | 1361 | ctx->parent_ctx = NULL; |
5a3126d4 | 1362 | ctx->generation++; |
211de6eb PZ |
1363 | |
1364 | return parent_ctx; | |
71a851b4 PZ |
1365 | } |
1366 | ||
1d953111 ON |
1367 | static u32 perf_event_pid_type(struct perf_event *event, struct task_struct *p, |
1368 | enum pid_type type) | |
6844c09d | 1369 | { |
1d953111 | 1370 | u32 nr; |
6844c09d ACM |
1371 | /* |
1372 | * only top level events have the pid namespace they were created in | |
1373 | */ | |
1374 | if (event->parent) | |
1375 | event = event->parent; | |
1376 | ||
1d953111 ON |
1377 | nr = __task_pid_nr_ns(p, type, event->ns); |
1378 | /* avoid -1 if it is idle thread or runs in another ns */ | |
1379 | if (!nr && !pid_alive(p)) | |
1380 | nr = -1; | |
1381 | return nr; | |
6844c09d ACM |
1382 | } |
1383 | ||
1d953111 | 1384 | static u32 perf_event_pid(struct perf_event *event, struct task_struct *p) |
6844c09d | 1385 | { |
6883f81a | 1386 | return perf_event_pid_type(event, p, PIDTYPE_TGID); |
1d953111 | 1387 | } |
6844c09d | 1388 | |
1d953111 ON |
1389 | static u32 perf_event_tid(struct perf_event *event, struct task_struct *p) |
1390 | { | |
1391 | return perf_event_pid_type(event, p, PIDTYPE_PID); | |
6844c09d ACM |
1392 | } |
1393 | ||
7f453c24 | 1394 | /* |
cdd6c482 | 1395 | * If we inherit events we want to return the parent event id |
7f453c24 PZ |
1396 | * to userspace. |
1397 | */ | |
cdd6c482 | 1398 | static u64 primary_event_id(struct perf_event *event) |
7f453c24 | 1399 | { |
cdd6c482 | 1400 | u64 id = event->id; |
7f453c24 | 1401 | |
cdd6c482 IM |
1402 | if (event->parent) |
1403 | id = event->parent->id; | |
7f453c24 PZ |
1404 | |
1405 | return id; | |
1406 | } | |
1407 | ||
25346b93 | 1408 | /* |
cdd6c482 | 1409 | * Get the perf_event_context for a task and lock it. |
63b6da39 | 1410 | * |
25346b93 PM |
1411 | * This has to cope with with the fact that until it is locked, |
1412 | * the context could get moved to another task. | |
1413 | */ | |
cdd6c482 | 1414 | static struct perf_event_context * |
8dc85d54 | 1415 | perf_lock_task_context(struct task_struct *task, int ctxn, unsigned long *flags) |
25346b93 | 1416 | { |
cdd6c482 | 1417 | struct perf_event_context *ctx; |
25346b93 | 1418 | |
9ed6060d | 1419 | retry: |
058ebd0e PZ |
1420 | /* |
1421 | * One of the few rules of preemptible RCU is that one cannot do | |
1422 | * rcu_read_unlock() while holding a scheduler (or nested) lock when | |
2fd59077 | 1423 | * part of the read side critical section was irqs-enabled -- see |
058ebd0e PZ |
1424 | * rcu_read_unlock_special(). |
1425 | * | |
1426 | * Since ctx->lock nests under rq->lock we must ensure the entire read | |
2fd59077 | 1427 | * side critical section has interrupts disabled. |
058ebd0e | 1428 | */ |
2fd59077 | 1429 | local_irq_save(*flags); |
058ebd0e | 1430 | rcu_read_lock(); |
8dc85d54 | 1431 | ctx = rcu_dereference(task->perf_event_ctxp[ctxn]); |
25346b93 PM |
1432 | if (ctx) { |
1433 | /* | |
1434 | * If this context is a clone of another, it might | |
1435 | * get swapped for another underneath us by | |
cdd6c482 | 1436 | * perf_event_task_sched_out, though the |
25346b93 PM |
1437 | * rcu_read_lock() protects us from any context |
1438 | * getting freed. Lock the context and check if it | |
1439 | * got swapped before we could get the lock, and retry | |
1440 | * if so. If we locked the right context, then it | |
1441 | * can't get swapped on us any more. | |
1442 | */ | |
2fd59077 | 1443 | raw_spin_lock(&ctx->lock); |
8dc85d54 | 1444 | if (ctx != rcu_dereference(task->perf_event_ctxp[ctxn])) { |
2fd59077 | 1445 | raw_spin_unlock(&ctx->lock); |
058ebd0e | 1446 | rcu_read_unlock(); |
2fd59077 | 1447 | local_irq_restore(*flags); |
25346b93 PM |
1448 | goto retry; |
1449 | } | |
b49a9e7e | 1450 | |
63b6da39 | 1451 | if (ctx->task == TASK_TOMBSTONE || |
8c94abbb | 1452 | !refcount_inc_not_zero(&ctx->refcount)) { |
2fd59077 | 1453 | raw_spin_unlock(&ctx->lock); |
b49a9e7e | 1454 | ctx = NULL; |
828b6f0e PZ |
1455 | } else { |
1456 | WARN_ON_ONCE(ctx->task != task); | |
b49a9e7e | 1457 | } |
25346b93 PM |
1458 | } |
1459 | rcu_read_unlock(); | |
2fd59077 PM |
1460 | if (!ctx) |
1461 | local_irq_restore(*flags); | |
25346b93 PM |
1462 | return ctx; |
1463 | } | |
1464 | ||
1465 | /* | |
1466 | * Get the context for a task and increment its pin_count so it | |
1467 | * can't get swapped to another task. This also increments its | |
1468 | * reference count so that the context can't get freed. | |
1469 | */ | |
8dc85d54 PZ |
1470 | static struct perf_event_context * |
1471 | perf_pin_task_context(struct task_struct *task, int ctxn) | |
25346b93 | 1472 | { |
cdd6c482 | 1473 | struct perf_event_context *ctx; |
25346b93 PM |
1474 | unsigned long flags; |
1475 | ||
8dc85d54 | 1476 | ctx = perf_lock_task_context(task, ctxn, &flags); |
25346b93 PM |
1477 | if (ctx) { |
1478 | ++ctx->pin_count; | |
e625cce1 | 1479 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1480 | } |
1481 | return ctx; | |
1482 | } | |
1483 | ||
cdd6c482 | 1484 | static void perf_unpin_context(struct perf_event_context *ctx) |
25346b93 PM |
1485 | { |
1486 | unsigned long flags; | |
1487 | ||
e625cce1 | 1488 | raw_spin_lock_irqsave(&ctx->lock, flags); |
25346b93 | 1489 | --ctx->pin_count; |
e625cce1 | 1490 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1491 | } |
1492 | ||
f67218c3 PZ |
1493 | /* |
1494 | * Update the record of the current time in a context. | |
1495 | */ | |
1496 | static void update_context_time(struct perf_event_context *ctx) | |
1497 | { | |
1498 | u64 now = perf_clock(); | |
1499 | ||
1500 | ctx->time += now - ctx->timestamp; | |
1501 | ctx->timestamp = now; | |
1502 | } | |
1503 | ||
4158755d SE |
1504 | static u64 perf_event_time(struct perf_event *event) |
1505 | { | |
1506 | struct perf_event_context *ctx = event->ctx; | |
e5d1367f SE |
1507 | |
1508 | if (is_cgroup_event(event)) | |
1509 | return perf_cgroup_event_time(event); | |
1510 | ||
4158755d SE |
1511 | return ctx ? ctx->time : 0; |
1512 | } | |
1513 | ||
487f05e1 AS |
1514 | static enum event_type_t get_event_type(struct perf_event *event) |
1515 | { | |
1516 | struct perf_event_context *ctx = event->ctx; | |
1517 | enum event_type_t event_type; | |
1518 | ||
1519 | lockdep_assert_held(&ctx->lock); | |
1520 | ||
3bda69c1 AS |
1521 | /* |
1522 | * It's 'group type', really, because if our group leader is | |
1523 | * pinned, so are we. | |
1524 | */ | |
1525 | if (event->group_leader != event) | |
1526 | event = event->group_leader; | |
1527 | ||
487f05e1 AS |
1528 | event_type = event->attr.pinned ? EVENT_PINNED : EVENT_FLEXIBLE; |
1529 | if (!ctx->task) | |
1530 | event_type |= EVENT_CPU; | |
1531 | ||
1532 | return event_type; | |
1533 | } | |
1534 | ||
8e1a2031 | 1535 | /* |
161c85fa | 1536 | * Helper function to initialize event group nodes. |
8e1a2031 | 1537 | */ |
161c85fa | 1538 | static void init_event_group(struct perf_event *event) |
8e1a2031 AB |
1539 | { |
1540 | RB_CLEAR_NODE(&event->group_node); | |
1541 | event->group_index = 0; | |
1542 | } | |
1543 | ||
1544 | /* | |
1545 | * Extract pinned or flexible groups from the context | |
161c85fa | 1546 | * based on event attrs bits. |
8e1a2031 AB |
1547 | */ |
1548 | static struct perf_event_groups * | |
1549 | get_event_groups(struct perf_event *event, struct perf_event_context *ctx) | |
889ff015 FW |
1550 | { |
1551 | if (event->attr.pinned) | |
1552 | return &ctx->pinned_groups; | |
1553 | else | |
1554 | return &ctx->flexible_groups; | |
1555 | } | |
1556 | ||
8e1a2031 | 1557 | /* |
161c85fa | 1558 | * Helper function to initializes perf_event_group trees. |
8e1a2031 | 1559 | */ |
161c85fa | 1560 | static void perf_event_groups_init(struct perf_event_groups *groups) |
8e1a2031 AB |
1561 | { |
1562 | groups->tree = RB_ROOT; | |
1563 | groups->index = 0; | |
1564 | } | |
1565 | ||
1566 | /* | |
1567 | * Compare function for event groups; | |
161c85fa PZ |
1568 | * |
1569 | * Implements complex key that first sorts by CPU and then by virtual index | |
1570 | * which provides ordering when rotating groups for the same CPU. | |
8e1a2031 | 1571 | */ |
161c85fa PZ |
1572 | static bool |
1573 | perf_event_groups_less(struct perf_event *left, struct perf_event *right) | |
8e1a2031 | 1574 | { |
161c85fa PZ |
1575 | if (left->cpu < right->cpu) |
1576 | return true; | |
1577 | if (left->cpu > right->cpu) | |
1578 | return false; | |
1579 | ||
95ed6c70 IR |
1580 | #ifdef CONFIG_CGROUP_PERF |
1581 | if (left->cgrp != right->cgrp) { | |
1582 | if (!left->cgrp || !left->cgrp->css.cgroup) { | |
1583 | /* | |
1584 | * Left has no cgroup but right does, no cgroups come | |
1585 | * first. | |
1586 | */ | |
1587 | return true; | |
1588 | } | |
1589 | if (!right->cgrp || right->cgrp->css.cgroup) { | |
1590 | /* | |
1591 | * Right has no cgroup but left does, no cgroups come | |
1592 | * first. | |
1593 | */ | |
1594 | return false; | |
1595 | } | |
1596 | /* Two dissimilar cgroups, order by id. */ | |
1597 | if (left->cgrp->css.cgroup->kn->id < right->cgrp->css.cgroup->kn->id) | |
1598 | return true; | |
1599 | ||
1600 | return false; | |
1601 | } | |
1602 | #endif | |
1603 | ||
161c85fa PZ |
1604 | if (left->group_index < right->group_index) |
1605 | return true; | |
1606 | if (left->group_index > right->group_index) | |
1607 | return false; | |
1608 | ||
1609 | return false; | |
8e1a2031 AB |
1610 | } |
1611 | ||
1612 | /* | |
161c85fa PZ |
1613 | * Insert @event into @groups' tree; using {@event->cpu, ++@groups->index} for |
1614 | * key (see perf_event_groups_less). This places it last inside the CPU | |
1615 | * subtree. | |
8e1a2031 AB |
1616 | */ |
1617 | static void | |
1618 | perf_event_groups_insert(struct perf_event_groups *groups, | |
161c85fa | 1619 | struct perf_event *event) |
8e1a2031 AB |
1620 | { |
1621 | struct perf_event *node_event; | |
1622 | struct rb_node *parent; | |
1623 | struct rb_node **node; | |
1624 | ||
1625 | event->group_index = ++groups->index; | |
1626 | ||
1627 | node = &groups->tree.rb_node; | |
1628 | parent = *node; | |
1629 | ||
1630 | while (*node) { | |
1631 | parent = *node; | |
161c85fa | 1632 | node_event = container_of(*node, struct perf_event, group_node); |
8e1a2031 AB |
1633 | |
1634 | if (perf_event_groups_less(event, node_event)) | |
1635 | node = &parent->rb_left; | |
1636 | else | |
1637 | node = &parent->rb_right; | |
1638 | } | |
1639 | ||
1640 | rb_link_node(&event->group_node, parent, node); | |
1641 | rb_insert_color(&event->group_node, &groups->tree); | |
1642 | } | |
1643 | ||
1644 | /* | |
161c85fa | 1645 | * Helper function to insert event into the pinned or flexible groups. |
8e1a2031 AB |
1646 | */ |
1647 | static void | |
1648 | add_event_to_groups(struct perf_event *event, struct perf_event_context *ctx) | |
1649 | { | |
1650 | struct perf_event_groups *groups; | |
1651 | ||
1652 | groups = get_event_groups(event, ctx); | |
1653 | perf_event_groups_insert(groups, event); | |
1654 | } | |
1655 | ||
1656 | /* | |
161c85fa | 1657 | * Delete a group from a tree. |
8e1a2031 AB |
1658 | */ |
1659 | static void | |
1660 | perf_event_groups_delete(struct perf_event_groups *groups, | |
161c85fa | 1661 | struct perf_event *event) |
8e1a2031 | 1662 | { |
161c85fa PZ |
1663 | WARN_ON_ONCE(RB_EMPTY_NODE(&event->group_node) || |
1664 | RB_EMPTY_ROOT(&groups->tree)); | |
8e1a2031 | 1665 | |
161c85fa | 1666 | rb_erase(&event->group_node, &groups->tree); |
8e1a2031 AB |
1667 | init_event_group(event); |
1668 | } | |
1669 | ||
1670 | /* | |
161c85fa | 1671 | * Helper function to delete event from its groups. |
8e1a2031 AB |
1672 | */ |
1673 | static void | |
1674 | del_event_from_groups(struct perf_event *event, struct perf_event_context *ctx) | |
1675 | { | |
1676 | struct perf_event_groups *groups; | |
1677 | ||
1678 | groups = get_event_groups(event, ctx); | |
1679 | perf_event_groups_delete(groups, event); | |
1680 | } | |
1681 | ||
1682 | /* | |
95ed6c70 | 1683 | * Get the leftmost event in the cpu/cgroup subtree. |
8e1a2031 AB |
1684 | */ |
1685 | static struct perf_event * | |
95ed6c70 IR |
1686 | perf_event_groups_first(struct perf_event_groups *groups, int cpu, |
1687 | struct cgroup *cgrp) | |
8e1a2031 AB |
1688 | { |
1689 | struct perf_event *node_event = NULL, *match = NULL; | |
1690 | struct rb_node *node = groups->tree.rb_node; | |
95ed6c70 IR |
1691 | #ifdef CONFIG_CGROUP_PERF |
1692 | u64 node_cgrp_id, cgrp_id = 0; | |
1693 | ||
1694 | if (cgrp) | |
1695 | cgrp_id = cgrp->kn->id; | |
1696 | #endif | |
8e1a2031 AB |
1697 | |
1698 | while (node) { | |
161c85fa | 1699 | node_event = container_of(node, struct perf_event, group_node); |
8e1a2031 AB |
1700 | |
1701 | if (cpu < node_event->cpu) { | |
1702 | node = node->rb_left; | |
95ed6c70 IR |
1703 | continue; |
1704 | } | |
1705 | if (cpu > node_event->cpu) { | |
8e1a2031 | 1706 | node = node->rb_right; |
95ed6c70 IR |
1707 | continue; |
1708 | } | |
1709 | #ifdef CONFIG_CGROUP_PERF | |
1710 | node_cgrp_id = 0; | |
1711 | if (node_event->cgrp && node_event->cgrp->css.cgroup) | |
1712 | node_cgrp_id = node_event->cgrp->css.cgroup->kn->id; | |
1713 | ||
1714 | if (cgrp_id < node_cgrp_id) { | |
8e1a2031 | 1715 | node = node->rb_left; |
95ed6c70 IR |
1716 | continue; |
1717 | } | |
1718 | if (cgrp_id > node_cgrp_id) { | |
1719 | node = node->rb_right; | |
1720 | continue; | |
8e1a2031 | 1721 | } |
95ed6c70 IR |
1722 | #endif |
1723 | match = node_event; | |
1724 | node = node->rb_left; | |
8e1a2031 AB |
1725 | } |
1726 | ||
1727 | return match; | |
1728 | } | |
1729 | ||
1cac7b1a PZ |
1730 | /* |
1731 | * Like rb_entry_next_safe() for the @cpu subtree. | |
1732 | */ | |
1733 | static struct perf_event * | |
1734 | perf_event_groups_next(struct perf_event *event) | |
1735 | { | |
1736 | struct perf_event *next; | |
95ed6c70 IR |
1737 | #ifdef CONFIG_CGROUP_PERF |
1738 | u64 curr_cgrp_id = 0; | |
1739 | u64 next_cgrp_id = 0; | |
1740 | #endif | |
1cac7b1a PZ |
1741 | |
1742 | next = rb_entry_safe(rb_next(&event->group_node), typeof(*event), group_node); | |
95ed6c70 IR |
1743 | if (next == NULL || next->cpu != event->cpu) |
1744 | return NULL; | |
1745 | ||
1746 | #ifdef CONFIG_CGROUP_PERF | |
1747 | if (event->cgrp && event->cgrp->css.cgroup) | |
1748 | curr_cgrp_id = event->cgrp->css.cgroup->kn->id; | |
1cac7b1a | 1749 | |
95ed6c70 IR |
1750 | if (next->cgrp && next->cgrp->css.cgroup) |
1751 | next_cgrp_id = next->cgrp->css.cgroup->kn->id; | |
1752 | ||
1753 | if (curr_cgrp_id != next_cgrp_id) | |
1754 | return NULL; | |
1755 | #endif | |
1756 | return next; | |
1cac7b1a PZ |
1757 | } |
1758 | ||
8e1a2031 | 1759 | /* |
161c85fa | 1760 | * Iterate through the whole groups tree. |
8e1a2031 | 1761 | */ |
6e6804d2 PZ |
1762 | #define perf_event_groups_for_each(event, groups) \ |
1763 | for (event = rb_entry_safe(rb_first(&((groups)->tree)), \ | |
1764 | typeof(*event), group_node); event; \ | |
1765 | event = rb_entry_safe(rb_next(&event->group_node), \ | |
1766 | typeof(*event), group_node)) | |
8e1a2031 | 1767 | |
fccc714b | 1768 | /* |
788faab7 | 1769 | * Add an event from the lists for its context. |
fccc714b PZ |
1770 | * Must be called with ctx->mutex and ctx->lock held. |
1771 | */ | |
04289bb9 | 1772 | static void |
cdd6c482 | 1773 | list_add_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1774 | { |
c994d613 PZ |
1775 | lockdep_assert_held(&ctx->lock); |
1776 | ||
8a49542c PZ |
1777 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); |
1778 | event->attach_state |= PERF_ATTACH_CONTEXT; | |
04289bb9 | 1779 | |
0d3d73aa PZ |
1780 | event->tstamp = perf_event_time(event); |
1781 | ||
04289bb9 | 1782 | /* |
8a49542c PZ |
1783 | * If we're a stand alone event or group leader, we go to the context |
1784 | * list, group events are kept attached to the group so that | |
1785 | * perf_group_detach can, at all times, locate all siblings. | |
04289bb9 | 1786 | */ |
8a49542c | 1787 | if (event->group_leader == event) { |
4ff6a8de | 1788 | event->group_caps = event->event_caps; |
8e1a2031 | 1789 | add_event_to_groups(event, ctx); |
5c148194 | 1790 | } |
592903cd | 1791 | |
db4a8356 | 1792 | list_update_cgroup_event(event, ctx, true); |
e5d1367f | 1793 | |
cdd6c482 IM |
1794 | list_add_rcu(&event->event_entry, &ctx->event_list); |
1795 | ctx->nr_events++; | |
1796 | if (event->attr.inherit_stat) | |
bfbd3381 | 1797 | ctx->nr_stat++; |
5a3126d4 PZ |
1798 | |
1799 | ctx->generation++; | |
04289bb9 IM |
1800 | } |
1801 | ||
0231bb53 JO |
1802 | /* |
1803 | * Initialize event state based on the perf_event_attr::disabled. | |
1804 | */ | |
1805 | static inline void perf_event__state_init(struct perf_event *event) | |
1806 | { | |
1807 | event->state = event->attr.disabled ? PERF_EVENT_STATE_OFF : | |
1808 | PERF_EVENT_STATE_INACTIVE; | |
1809 | } | |
1810 | ||
a723968c | 1811 | static void __perf_event_read_size(struct perf_event *event, int nr_siblings) |
c320c7b7 ACM |
1812 | { |
1813 | int entry = sizeof(u64); /* value */ | |
1814 | int size = 0; | |
1815 | int nr = 1; | |
1816 | ||
1817 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
1818 | size += sizeof(u64); | |
1819 | ||
1820 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
1821 | size += sizeof(u64); | |
1822 | ||
1823 | if (event->attr.read_format & PERF_FORMAT_ID) | |
1824 | entry += sizeof(u64); | |
1825 | ||
1826 | if (event->attr.read_format & PERF_FORMAT_GROUP) { | |
a723968c | 1827 | nr += nr_siblings; |
c320c7b7 ACM |
1828 | size += sizeof(u64); |
1829 | } | |
1830 | ||
1831 | size += entry * nr; | |
1832 | event->read_size = size; | |
1833 | } | |
1834 | ||
a723968c | 1835 | static void __perf_event_header_size(struct perf_event *event, u64 sample_type) |
c320c7b7 ACM |
1836 | { |
1837 | struct perf_sample_data *data; | |
c320c7b7 ACM |
1838 | u16 size = 0; |
1839 | ||
c320c7b7 ACM |
1840 | if (sample_type & PERF_SAMPLE_IP) |
1841 | size += sizeof(data->ip); | |
1842 | ||
6844c09d ACM |
1843 | if (sample_type & PERF_SAMPLE_ADDR) |
1844 | size += sizeof(data->addr); | |
1845 | ||
1846 | if (sample_type & PERF_SAMPLE_PERIOD) | |
1847 | size += sizeof(data->period); | |
1848 | ||
c3feedf2 AK |
1849 | if (sample_type & PERF_SAMPLE_WEIGHT) |
1850 | size += sizeof(data->weight); | |
1851 | ||
6844c09d ACM |
1852 | if (sample_type & PERF_SAMPLE_READ) |
1853 | size += event->read_size; | |
1854 | ||
d6be9ad6 SE |
1855 | if (sample_type & PERF_SAMPLE_DATA_SRC) |
1856 | size += sizeof(data->data_src.val); | |
1857 | ||
fdfbbd07 AK |
1858 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
1859 | size += sizeof(data->txn); | |
1860 | ||
fc7ce9c7 KL |
1861 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) |
1862 | size += sizeof(data->phys_addr); | |
1863 | ||
6844c09d ACM |
1864 | event->header_size = size; |
1865 | } | |
1866 | ||
a723968c PZ |
1867 | /* |
1868 | * Called at perf_event creation and when events are attached/detached from a | |
1869 | * group. | |
1870 | */ | |
1871 | static void perf_event__header_size(struct perf_event *event) | |
1872 | { | |
1873 | __perf_event_read_size(event, | |
1874 | event->group_leader->nr_siblings); | |
1875 | __perf_event_header_size(event, event->attr.sample_type); | |
1876 | } | |
1877 | ||
6844c09d ACM |
1878 | static void perf_event__id_header_size(struct perf_event *event) |
1879 | { | |
1880 | struct perf_sample_data *data; | |
1881 | u64 sample_type = event->attr.sample_type; | |
1882 | u16 size = 0; | |
1883 | ||
c320c7b7 ACM |
1884 | if (sample_type & PERF_SAMPLE_TID) |
1885 | size += sizeof(data->tid_entry); | |
1886 | ||
1887 | if (sample_type & PERF_SAMPLE_TIME) | |
1888 | size += sizeof(data->time); | |
1889 | ||
ff3d527c AH |
1890 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
1891 | size += sizeof(data->id); | |
1892 | ||
c320c7b7 ACM |
1893 | if (sample_type & PERF_SAMPLE_ID) |
1894 | size += sizeof(data->id); | |
1895 | ||
1896 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
1897 | size += sizeof(data->stream_id); | |
1898 | ||
1899 | if (sample_type & PERF_SAMPLE_CPU) | |
1900 | size += sizeof(data->cpu_entry); | |
1901 | ||
6844c09d | 1902 | event->id_header_size = size; |
c320c7b7 ACM |
1903 | } |
1904 | ||
a723968c PZ |
1905 | static bool perf_event_validate_size(struct perf_event *event) |
1906 | { | |
1907 | /* | |
1908 | * The values computed here will be over-written when we actually | |
1909 | * attach the event. | |
1910 | */ | |
1911 | __perf_event_read_size(event, event->group_leader->nr_siblings + 1); | |
1912 | __perf_event_header_size(event, event->attr.sample_type & ~PERF_SAMPLE_READ); | |
1913 | perf_event__id_header_size(event); | |
1914 | ||
1915 | /* | |
1916 | * Sum the lot; should not exceed the 64k limit we have on records. | |
1917 | * Conservative limit to allow for callchains and other variable fields. | |
1918 | */ | |
1919 | if (event->read_size + event->header_size + | |
1920 | event->id_header_size + sizeof(struct perf_event_header) >= 16*1024) | |
1921 | return false; | |
1922 | ||
1923 | return true; | |
1924 | } | |
1925 | ||
8a49542c PZ |
1926 | static void perf_group_attach(struct perf_event *event) |
1927 | { | |
c320c7b7 | 1928 | struct perf_event *group_leader = event->group_leader, *pos; |
8a49542c | 1929 | |
a76a82a3 PZ |
1930 | lockdep_assert_held(&event->ctx->lock); |
1931 | ||
74c3337c PZ |
1932 | /* |
1933 | * We can have double attach due to group movement in perf_event_open. | |
1934 | */ | |
1935 | if (event->attach_state & PERF_ATTACH_GROUP) | |
1936 | return; | |
1937 | ||
8a49542c PZ |
1938 | event->attach_state |= PERF_ATTACH_GROUP; |
1939 | ||
1940 | if (group_leader == event) | |
1941 | return; | |
1942 | ||
652884fe PZ |
1943 | WARN_ON_ONCE(group_leader->ctx != event->ctx); |
1944 | ||
4ff6a8de | 1945 | group_leader->group_caps &= event->event_caps; |
8a49542c | 1946 | |
8343aae6 | 1947 | list_add_tail(&event->sibling_list, &group_leader->sibling_list); |
8a49542c | 1948 | group_leader->nr_siblings++; |
c320c7b7 ACM |
1949 | |
1950 | perf_event__header_size(group_leader); | |
1951 | ||
edb39592 | 1952 | for_each_sibling_event(pos, group_leader) |
c320c7b7 | 1953 | perf_event__header_size(pos); |
8a49542c PZ |
1954 | } |
1955 | ||
a63eaf34 | 1956 | /* |
788faab7 | 1957 | * Remove an event from the lists for its context. |
fccc714b | 1958 | * Must be called with ctx->mutex and ctx->lock held. |
a63eaf34 | 1959 | */ |
04289bb9 | 1960 | static void |
cdd6c482 | 1961 | list_del_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1962 | { |
652884fe PZ |
1963 | WARN_ON_ONCE(event->ctx != ctx); |
1964 | lockdep_assert_held(&ctx->lock); | |
1965 | ||
8a49542c PZ |
1966 | /* |
1967 | * We can have double detach due to exit/hot-unplug + close. | |
1968 | */ | |
1969 | if (!(event->attach_state & PERF_ATTACH_CONTEXT)) | |
a63eaf34 | 1970 | return; |
8a49542c PZ |
1971 | |
1972 | event->attach_state &= ~PERF_ATTACH_CONTEXT; | |
1973 | ||
db4a8356 | 1974 | list_update_cgroup_event(event, ctx, false); |
e5d1367f | 1975 | |
cdd6c482 IM |
1976 | ctx->nr_events--; |
1977 | if (event->attr.inherit_stat) | |
bfbd3381 | 1978 | ctx->nr_stat--; |
8bc20959 | 1979 | |
cdd6c482 | 1980 | list_del_rcu(&event->event_entry); |
04289bb9 | 1981 | |
8a49542c | 1982 | if (event->group_leader == event) |
8e1a2031 | 1983 | del_event_from_groups(event, ctx); |
5c148194 | 1984 | |
b2e74a26 SE |
1985 | /* |
1986 | * If event was in error state, then keep it | |
1987 | * that way, otherwise bogus counts will be | |
1988 | * returned on read(). The only way to get out | |
1989 | * of error state is by explicit re-enabling | |
1990 | * of the event | |
1991 | */ | |
1992 | if (event->state > PERF_EVENT_STATE_OFF) | |
0d3d73aa | 1993 | perf_event_set_state(event, PERF_EVENT_STATE_OFF); |
5a3126d4 PZ |
1994 | |
1995 | ctx->generation++; | |
050735b0 PZ |
1996 | } |
1997 | ||
ab43762e AS |
1998 | static int |
1999 | perf_aux_output_match(struct perf_event *event, struct perf_event *aux_event) | |
2000 | { | |
2001 | if (!has_aux(aux_event)) | |
2002 | return 0; | |
2003 | ||
2004 | if (!event->pmu->aux_output_match) | |
2005 | return 0; | |
2006 | ||
2007 | return event->pmu->aux_output_match(aux_event); | |
2008 | } | |
2009 | ||
2010 | static void put_event(struct perf_event *event); | |
2011 | static void event_sched_out(struct perf_event *event, | |
2012 | struct perf_cpu_context *cpuctx, | |
2013 | struct perf_event_context *ctx); | |
2014 | ||
2015 | static void perf_put_aux_event(struct perf_event *event) | |
2016 | { | |
2017 | struct perf_event_context *ctx = event->ctx; | |
2018 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
2019 | struct perf_event *iter; | |
2020 | ||
2021 | /* | |
2022 | * If event uses aux_event tear down the link | |
2023 | */ | |
2024 | if (event->aux_event) { | |
2025 | iter = event->aux_event; | |
2026 | event->aux_event = NULL; | |
2027 | put_event(iter); | |
2028 | return; | |
2029 | } | |
2030 | ||
2031 | /* | |
2032 | * If the event is an aux_event, tear down all links to | |
2033 | * it from other events. | |
2034 | */ | |
2035 | for_each_sibling_event(iter, event->group_leader) { | |
2036 | if (iter->aux_event != event) | |
2037 | continue; | |
2038 | ||
2039 | iter->aux_event = NULL; | |
2040 | put_event(event); | |
2041 | ||
2042 | /* | |
2043 | * If it's ACTIVE, schedule it out and put it into ERROR | |
2044 | * state so that we don't try to schedule it again. Note | |
2045 | * that perf_event_enable() will clear the ERROR status. | |
2046 | */ | |
2047 | event_sched_out(iter, cpuctx, ctx); | |
2048 | perf_event_set_state(event, PERF_EVENT_STATE_ERROR); | |
2049 | } | |
2050 | } | |
2051 | ||
a4faf00d AS |
2052 | static bool perf_need_aux_event(struct perf_event *event) |
2053 | { | |
2054 | return !!event->attr.aux_output || !!event->attr.aux_sample_size; | |
2055 | } | |
2056 | ||
ab43762e AS |
2057 | static int perf_get_aux_event(struct perf_event *event, |
2058 | struct perf_event *group_leader) | |
2059 | { | |
2060 | /* | |
2061 | * Our group leader must be an aux event if we want to be | |
2062 | * an aux_output. This way, the aux event will precede its | |
2063 | * aux_output events in the group, and therefore will always | |
2064 | * schedule first. | |
2065 | */ | |
2066 | if (!group_leader) | |
2067 | return 0; | |
2068 | ||
a4faf00d AS |
2069 | /* |
2070 | * aux_output and aux_sample_size are mutually exclusive. | |
2071 | */ | |
2072 | if (event->attr.aux_output && event->attr.aux_sample_size) | |
2073 | return 0; | |
2074 | ||
2075 | if (event->attr.aux_output && | |
2076 | !perf_aux_output_match(event, group_leader)) | |
2077 | return 0; | |
2078 | ||
2079 | if (event->attr.aux_sample_size && !group_leader->pmu->snapshot_aux) | |
ab43762e AS |
2080 | return 0; |
2081 | ||
2082 | if (!atomic_long_inc_not_zero(&group_leader->refcount)) | |
2083 | return 0; | |
2084 | ||
2085 | /* | |
2086 | * Link aux_outputs to their aux event; this is undone in | |
2087 | * perf_group_detach() by perf_put_aux_event(). When the | |
2088 | * group in torn down, the aux_output events loose their | |
2089 | * link to the aux_event and can't schedule any more. | |
2090 | */ | |
2091 | event->aux_event = group_leader; | |
2092 | ||
2093 | return 1; | |
2094 | } | |
2095 | ||
ab6f824c PZ |
2096 | static inline struct list_head *get_event_list(struct perf_event *event) |
2097 | { | |
2098 | struct perf_event_context *ctx = event->ctx; | |
2099 | return event->attr.pinned ? &ctx->pinned_active : &ctx->flexible_active; | |
2100 | } | |
2101 | ||
8a49542c | 2102 | static void perf_group_detach(struct perf_event *event) |
050735b0 PZ |
2103 | { |
2104 | struct perf_event *sibling, *tmp; | |
6668128a | 2105 | struct perf_event_context *ctx = event->ctx; |
8a49542c | 2106 | |
6668128a | 2107 | lockdep_assert_held(&ctx->lock); |
a76a82a3 | 2108 | |
8a49542c PZ |
2109 | /* |
2110 | * We can have double detach due to exit/hot-unplug + close. | |
2111 | */ | |
2112 | if (!(event->attach_state & PERF_ATTACH_GROUP)) | |
2113 | return; | |
2114 | ||
2115 | event->attach_state &= ~PERF_ATTACH_GROUP; | |
2116 | ||
ab43762e AS |
2117 | perf_put_aux_event(event); |
2118 | ||
8a49542c PZ |
2119 | /* |
2120 | * If this is a sibling, remove it from its group. | |
2121 | */ | |
2122 | if (event->group_leader != event) { | |
8343aae6 | 2123 | list_del_init(&event->sibling_list); |
8a49542c | 2124 | event->group_leader->nr_siblings--; |
c320c7b7 | 2125 | goto out; |
8a49542c PZ |
2126 | } |
2127 | ||
04289bb9 | 2128 | /* |
cdd6c482 IM |
2129 | * If this was a group event with sibling events then |
2130 | * upgrade the siblings to singleton events by adding them | |
8a49542c | 2131 | * to whatever list we are on. |
04289bb9 | 2132 | */ |
8343aae6 | 2133 | list_for_each_entry_safe(sibling, tmp, &event->sibling_list, sibling_list) { |
8e1a2031 | 2134 | |
04289bb9 | 2135 | sibling->group_leader = sibling; |
24868367 | 2136 | list_del_init(&sibling->sibling_list); |
d6f962b5 FW |
2137 | |
2138 | /* Inherit group flags from the previous leader */ | |
4ff6a8de | 2139 | sibling->group_caps = event->group_caps; |
652884fe | 2140 | |
8e1a2031 | 2141 | if (!RB_EMPTY_NODE(&event->group_node)) { |
8e1a2031 | 2142 | add_event_to_groups(sibling, event->ctx); |
6668128a | 2143 | |
ab6f824c PZ |
2144 | if (sibling->state == PERF_EVENT_STATE_ACTIVE) |
2145 | list_add_tail(&sibling->active_list, get_event_list(sibling)); | |
8e1a2031 AB |
2146 | } |
2147 | ||
652884fe | 2148 | WARN_ON_ONCE(sibling->ctx != event->ctx); |
04289bb9 | 2149 | } |
c320c7b7 ACM |
2150 | |
2151 | out: | |
2152 | perf_event__header_size(event->group_leader); | |
2153 | ||
edb39592 | 2154 | for_each_sibling_event(tmp, event->group_leader) |
c320c7b7 | 2155 | perf_event__header_size(tmp); |
04289bb9 IM |
2156 | } |
2157 | ||
fadfe7be JO |
2158 | static bool is_orphaned_event(struct perf_event *event) |
2159 | { | |
a69b0ca4 | 2160 | return event->state == PERF_EVENT_STATE_DEAD; |
fadfe7be JO |
2161 | } |
2162 | ||
2c81a647 | 2163 | static inline int __pmu_filter_match(struct perf_event *event) |
66eb579e MR |
2164 | { |
2165 | struct pmu *pmu = event->pmu; | |
2166 | return pmu->filter_match ? pmu->filter_match(event) : 1; | |
2167 | } | |
2168 | ||
2c81a647 MR |
2169 | /* |
2170 | * Check whether we should attempt to schedule an event group based on | |
2171 | * PMU-specific filtering. An event group can consist of HW and SW events, | |
2172 | * potentially with a SW leader, so we must check all the filters, to | |
2173 | * determine whether a group is schedulable: | |
2174 | */ | |
2175 | static inline int pmu_filter_match(struct perf_event *event) | |
2176 | { | |
edb39592 | 2177 | struct perf_event *sibling; |
2c81a647 MR |
2178 | |
2179 | if (!__pmu_filter_match(event)) | |
2180 | return 0; | |
2181 | ||
edb39592 PZ |
2182 | for_each_sibling_event(sibling, event) { |
2183 | if (!__pmu_filter_match(sibling)) | |
2c81a647 MR |
2184 | return 0; |
2185 | } | |
2186 | ||
2187 | return 1; | |
2188 | } | |
2189 | ||
fa66f07a SE |
2190 | static inline int |
2191 | event_filter_match(struct perf_event *event) | |
2192 | { | |
0b8f1e2e PZ |
2193 | return (event->cpu == -1 || event->cpu == smp_processor_id()) && |
2194 | perf_cgroup_match(event) && pmu_filter_match(event); | |
fa66f07a SE |
2195 | } |
2196 | ||
9ffcfa6f SE |
2197 | static void |
2198 | event_sched_out(struct perf_event *event, | |
3b6f9e5c | 2199 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 2200 | struct perf_event_context *ctx) |
3b6f9e5c | 2201 | { |
0d3d73aa | 2202 | enum perf_event_state state = PERF_EVENT_STATE_INACTIVE; |
652884fe PZ |
2203 | |
2204 | WARN_ON_ONCE(event->ctx != ctx); | |
2205 | lockdep_assert_held(&ctx->lock); | |
2206 | ||
cdd6c482 | 2207 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
9ffcfa6f | 2208 | return; |
3b6f9e5c | 2209 | |
6668128a PZ |
2210 | /* |
2211 | * Asymmetry; we only schedule events _IN_ through ctx_sched_in(), but | |
2212 | * we can schedule events _OUT_ individually through things like | |
2213 | * __perf_remove_from_context(). | |
2214 | */ | |
2215 | list_del_init(&event->active_list); | |
2216 | ||
44377277 AS |
2217 | perf_pmu_disable(event->pmu); |
2218 | ||
28a967c3 PZ |
2219 | event->pmu->del(event, 0); |
2220 | event->oncpu = -1; | |
0d3d73aa | 2221 | |
1d54ad94 PZ |
2222 | if (READ_ONCE(event->pending_disable) >= 0) { |
2223 | WRITE_ONCE(event->pending_disable, -1); | |
0d3d73aa | 2224 | state = PERF_EVENT_STATE_OFF; |
970892a9 | 2225 | } |
0d3d73aa | 2226 | perf_event_set_state(event, state); |
3b6f9e5c | 2227 | |
cdd6c482 | 2228 | if (!is_software_event(event)) |
3b6f9e5c | 2229 | cpuctx->active_oncpu--; |
2fde4f94 MR |
2230 | if (!--ctx->nr_active) |
2231 | perf_event_ctx_deactivate(ctx); | |
0f5a2601 PZ |
2232 | if (event->attr.freq && event->attr.sample_freq) |
2233 | ctx->nr_freq--; | |
cdd6c482 | 2234 | if (event->attr.exclusive || !cpuctx->active_oncpu) |
3b6f9e5c | 2235 | cpuctx->exclusive = 0; |
44377277 AS |
2236 | |
2237 | perf_pmu_enable(event->pmu); | |
3b6f9e5c PM |
2238 | } |
2239 | ||
d859e29f | 2240 | static void |
cdd6c482 | 2241 | group_sched_out(struct perf_event *group_event, |
d859e29f | 2242 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 2243 | struct perf_event_context *ctx) |
d859e29f | 2244 | { |
cdd6c482 | 2245 | struct perf_event *event; |
0d3d73aa PZ |
2246 | |
2247 | if (group_event->state != PERF_EVENT_STATE_ACTIVE) | |
2248 | return; | |
d859e29f | 2249 | |
3f005e7d MR |
2250 | perf_pmu_disable(ctx->pmu); |
2251 | ||
cdd6c482 | 2252 | event_sched_out(group_event, cpuctx, ctx); |
d859e29f PM |
2253 | |
2254 | /* | |
2255 | * Schedule out siblings (if any): | |
2256 | */ | |
edb39592 | 2257 | for_each_sibling_event(event, group_event) |
cdd6c482 | 2258 | event_sched_out(event, cpuctx, ctx); |
d859e29f | 2259 | |
3f005e7d MR |
2260 | perf_pmu_enable(ctx->pmu); |
2261 | ||
0d3d73aa | 2262 | if (group_event->attr.exclusive) |
d859e29f PM |
2263 | cpuctx->exclusive = 0; |
2264 | } | |
2265 | ||
45a0e07a | 2266 | #define DETACH_GROUP 0x01UL |
0017960f | 2267 | |
0793a61d | 2268 | /* |
cdd6c482 | 2269 | * Cross CPU call to remove a performance event |
0793a61d | 2270 | * |
cdd6c482 | 2271 | * We disable the event on the hardware level first. After that we |
0793a61d TG |
2272 | * remove it from the context list. |
2273 | */ | |
fae3fde6 PZ |
2274 | static void |
2275 | __perf_remove_from_context(struct perf_event *event, | |
2276 | struct perf_cpu_context *cpuctx, | |
2277 | struct perf_event_context *ctx, | |
2278 | void *info) | |
0793a61d | 2279 | { |
45a0e07a | 2280 | unsigned long flags = (unsigned long)info; |
0793a61d | 2281 | |
3c5c8711 PZ |
2282 | if (ctx->is_active & EVENT_TIME) { |
2283 | update_context_time(ctx); | |
2284 | update_cgrp_time_from_cpuctx(cpuctx); | |
2285 | } | |
2286 | ||
cdd6c482 | 2287 | event_sched_out(event, cpuctx, ctx); |
45a0e07a | 2288 | if (flags & DETACH_GROUP) |
46ce0fe9 | 2289 | perf_group_detach(event); |
cdd6c482 | 2290 | list_del_event(event, ctx); |
39a43640 PZ |
2291 | |
2292 | if (!ctx->nr_events && ctx->is_active) { | |
64ce3126 | 2293 | ctx->is_active = 0; |
90c91dfb | 2294 | ctx->rotate_necessary = 0; |
39a43640 PZ |
2295 | if (ctx->task) { |
2296 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
2297 | cpuctx->task_ctx = NULL; | |
2298 | } | |
64ce3126 | 2299 | } |
0793a61d TG |
2300 | } |
2301 | ||
0793a61d | 2302 | /* |
cdd6c482 | 2303 | * Remove the event from a task's (or a CPU's) list of events. |
0793a61d | 2304 | * |
cdd6c482 IM |
2305 | * If event->ctx is a cloned context, callers must make sure that |
2306 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 PM |
2307 | * remains valid. This is OK when called from perf_release since |
2308 | * that only calls us on the top-level context, which can't be a clone. | |
cdd6c482 | 2309 | * When called from perf_event_exit_task, it's OK because the |
c93f7669 | 2310 | * context has been detached from its task. |
0793a61d | 2311 | */ |
45a0e07a | 2312 | static void perf_remove_from_context(struct perf_event *event, unsigned long flags) |
0793a61d | 2313 | { |
a76a82a3 PZ |
2314 | struct perf_event_context *ctx = event->ctx; |
2315 | ||
2316 | lockdep_assert_held(&ctx->mutex); | |
0793a61d | 2317 | |
45a0e07a | 2318 | event_function_call(event, __perf_remove_from_context, (void *)flags); |
a76a82a3 PZ |
2319 | |
2320 | /* | |
2321 | * The above event_function_call() can NO-OP when it hits | |
2322 | * TASK_TOMBSTONE. In that case we must already have been detached | |
2323 | * from the context (by perf_event_exit_event()) but the grouping | |
2324 | * might still be in-tact. | |
2325 | */ | |
2326 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); | |
2327 | if ((flags & DETACH_GROUP) && | |
2328 | (event->attach_state & PERF_ATTACH_GROUP)) { | |
2329 | /* | |
2330 | * Since in that case we cannot possibly be scheduled, simply | |
2331 | * detach now. | |
2332 | */ | |
2333 | raw_spin_lock_irq(&ctx->lock); | |
2334 | perf_group_detach(event); | |
2335 | raw_spin_unlock_irq(&ctx->lock); | |
2336 | } | |
0793a61d TG |
2337 | } |
2338 | ||
d859e29f | 2339 | /* |
cdd6c482 | 2340 | * Cross CPU call to disable a performance event |
d859e29f | 2341 | */ |
fae3fde6 PZ |
2342 | static void __perf_event_disable(struct perf_event *event, |
2343 | struct perf_cpu_context *cpuctx, | |
2344 | struct perf_event_context *ctx, | |
2345 | void *info) | |
7b648018 | 2346 | { |
fae3fde6 PZ |
2347 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
2348 | return; | |
7b648018 | 2349 | |
3c5c8711 PZ |
2350 | if (ctx->is_active & EVENT_TIME) { |
2351 | update_context_time(ctx); | |
2352 | update_cgrp_time_from_event(event); | |
2353 | } | |
2354 | ||
fae3fde6 PZ |
2355 | if (event == event->group_leader) |
2356 | group_sched_out(event, cpuctx, ctx); | |
2357 | else | |
2358 | event_sched_out(event, cpuctx, ctx); | |
0d3d73aa PZ |
2359 | |
2360 | perf_event_set_state(event, PERF_EVENT_STATE_OFF); | |
7b648018 PZ |
2361 | } |
2362 | ||
d859e29f | 2363 | /* |
788faab7 | 2364 | * Disable an event. |
c93f7669 | 2365 | * |
cdd6c482 IM |
2366 | * If event->ctx is a cloned context, callers must make sure that |
2367 | * every task struct that event->ctx->task could possibly point to | |
9f014e3a | 2368 | * remains valid. This condition is satisfied when called through |
cdd6c482 IM |
2369 | * perf_event_for_each_child or perf_event_for_each because they |
2370 | * hold the top-level event's child_mutex, so any descendant that | |
8ba289b8 PZ |
2371 | * goes to exit will block in perf_event_exit_event(). |
2372 | * | |
cdd6c482 | 2373 | * When called from perf_pending_event it's OK because event->ctx |
c93f7669 | 2374 | * is the current context on this CPU and preemption is disabled, |
cdd6c482 | 2375 | * hence we can't get into perf_event_task_sched_out for this context. |
d859e29f | 2376 | */ |
f63a8daa | 2377 | static void _perf_event_disable(struct perf_event *event) |
d859e29f | 2378 | { |
cdd6c482 | 2379 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 2380 | |
e625cce1 | 2381 | raw_spin_lock_irq(&ctx->lock); |
7b648018 | 2382 | if (event->state <= PERF_EVENT_STATE_OFF) { |
e625cce1 | 2383 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 2384 | return; |
53cfbf59 | 2385 | } |
e625cce1 | 2386 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 2387 | |
fae3fde6 PZ |
2388 | event_function_call(event, __perf_event_disable, NULL); |
2389 | } | |
2390 | ||
2391 | void perf_event_disable_local(struct perf_event *event) | |
2392 | { | |
2393 | event_function_local(event, __perf_event_disable, NULL); | |
d859e29f | 2394 | } |
f63a8daa PZ |
2395 | |
2396 | /* | |
2397 | * Strictly speaking kernel users cannot create groups and therefore this | |
2398 | * interface does not need the perf_event_ctx_lock() magic. | |
2399 | */ | |
2400 | void perf_event_disable(struct perf_event *event) | |
2401 | { | |
2402 | struct perf_event_context *ctx; | |
2403 | ||
2404 | ctx = perf_event_ctx_lock(event); | |
2405 | _perf_event_disable(event); | |
2406 | perf_event_ctx_unlock(event, ctx); | |
2407 | } | |
dcfce4a0 | 2408 | EXPORT_SYMBOL_GPL(perf_event_disable); |
d859e29f | 2409 | |
5aab90ce JO |
2410 | void perf_event_disable_inatomic(struct perf_event *event) |
2411 | { | |
1d54ad94 PZ |
2412 | WRITE_ONCE(event->pending_disable, smp_processor_id()); |
2413 | /* can fail, see perf_pending_event_disable() */ | |
5aab90ce JO |
2414 | irq_work_queue(&event->pending); |
2415 | } | |
2416 | ||
e5d1367f | 2417 | static void perf_set_shadow_time(struct perf_event *event, |
0d3d73aa | 2418 | struct perf_event_context *ctx) |
e5d1367f SE |
2419 | { |
2420 | /* | |
2421 | * use the correct time source for the time snapshot | |
2422 | * | |
2423 | * We could get by without this by leveraging the | |
2424 | * fact that to get to this function, the caller | |
2425 | * has most likely already called update_context_time() | |
2426 | * and update_cgrp_time_xx() and thus both timestamp | |
2427 | * are identical (or very close). Given that tstamp is, | |
2428 | * already adjusted for cgroup, we could say that: | |
2429 | * tstamp - ctx->timestamp | |
2430 | * is equivalent to | |
2431 | * tstamp - cgrp->timestamp. | |
2432 | * | |
2433 | * Then, in perf_output_read(), the calculation would | |
2434 | * work with no changes because: | |
2435 | * - event is guaranteed scheduled in | |
2436 | * - no scheduled out in between | |
2437 | * - thus the timestamp would be the same | |
2438 | * | |
2439 | * But this is a bit hairy. | |
2440 | * | |
2441 | * So instead, we have an explicit cgroup call to remain | |
2442 | * within the time time source all along. We believe it | |
2443 | * is cleaner and simpler to understand. | |
2444 | */ | |
2445 | if (is_cgroup_event(event)) | |
0d3d73aa | 2446 | perf_cgroup_set_shadow_time(event, event->tstamp); |
e5d1367f | 2447 | else |
0d3d73aa | 2448 | event->shadow_ctx_time = event->tstamp - ctx->timestamp; |
e5d1367f SE |
2449 | } |
2450 | ||
4fe757dd PZ |
2451 | #define MAX_INTERRUPTS (~0ULL) |
2452 | ||
2453 | static void perf_log_throttle(struct perf_event *event, int enable); | |
ec0d7729 | 2454 | static void perf_log_itrace_start(struct perf_event *event); |
4fe757dd | 2455 | |
235c7fc7 | 2456 | static int |
9ffcfa6f | 2457 | event_sched_in(struct perf_event *event, |
235c7fc7 | 2458 | struct perf_cpu_context *cpuctx, |
6e37738a | 2459 | struct perf_event_context *ctx) |
235c7fc7 | 2460 | { |
44377277 | 2461 | int ret = 0; |
4158755d | 2462 | |
ab6f824c PZ |
2463 | WARN_ON_ONCE(event->ctx != ctx); |
2464 | ||
63342411 PZ |
2465 | lockdep_assert_held(&ctx->lock); |
2466 | ||
cdd6c482 | 2467 | if (event->state <= PERF_EVENT_STATE_OFF) |
235c7fc7 IM |
2468 | return 0; |
2469 | ||
95ff4ca2 AS |
2470 | WRITE_ONCE(event->oncpu, smp_processor_id()); |
2471 | /* | |
0c1cbc18 PZ |
2472 | * Order event::oncpu write to happen before the ACTIVE state is |
2473 | * visible. This allows perf_event_{stop,read}() to observe the correct | |
2474 | * ->oncpu if it sees ACTIVE. | |
95ff4ca2 AS |
2475 | */ |
2476 | smp_wmb(); | |
0d3d73aa | 2477 | perf_event_set_state(event, PERF_EVENT_STATE_ACTIVE); |
4fe757dd PZ |
2478 | |
2479 | /* | |
2480 | * Unthrottle events, since we scheduled we might have missed several | |
2481 | * ticks already, also for a heavily scheduling task there is little | |
2482 | * guarantee it'll get a tick in a timely manner. | |
2483 | */ | |
2484 | if (unlikely(event->hw.interrupts == MAX_INTERRUPTS)) { | |
2485 | perf_log_throttle(event, 1); | |
2486 | event->hw.interrupts = 0; | |
2487 | } | |
2488 | ||
44377277 AS |
2489 | perf_pmu_disable(event->pmu); |
2490 | ||
0d3d73aa | 2491 | perf_set_shadow_time(event, ctx); |
72f669c0 | 2492 | |
ec0d7729 AS |
2493 | perf_log_itrace_start(event); |
2494 | ||
a4eaf7f1 | 2495 | if (event->pmu->add(event, PERF_EF_START)) { |
0d3d73aa | 2496 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
cdd6c482 | 2497 | event->oncpu = -1; |
44377277 AS |
2498 | ret = -EAGAIN; |
2499 | goto out; | |
235c7fc7 IM |
2500 | } |
2501 | ||
cdd6c482 | 2502 | if (!is_software_event(event)) |
3b6f9e5c | 2503 | cpuctx->active_oncpu++; |
2fde4f94 MR |
2504 | if (!ctx->nr_active++) |
2505 | perf_event_ctx_activate(ctx); | |
0f5a2601 PZ |
2506 | if (event->attr.freq && event->attr.sample_freq) |
2507 | ctx->nr_freq++; | |
235c7fc7 | 2508 | |
cdd6c482 | 2509 | if (event->attr.exclusive) |
3b6f9e5c PM |
2510 | cpuctx->exclusive = 1; |
2511 | ||
44377277 AS |
2512 | out: |
2513 | perf_pmu_enable(event->pmu); | |
2514 | ||
2515 | return ret; | |
235c7fc7 IM |
2516 | } |
2517 | ||
6751b71e | 2518 | static int |
cdd6c482 | 2519 | group_sched_in(struct perf_event *group_event, |
6751b71e | 2520 | struct perf_cpu_context *cpuctx, |
6e37738a | 2521 | struct perf_event_context *ctx) |
6751b71e | 2522 | { |
6bde9b6c | 2523 | struct perf_event *event, *partial_group = NULL; |
4a234593 | 2524 | struct pmu *pmu = ctx->pmu; |
6751b71e | 2525 | |
cdd6c482 | 2526 | if (group_event->state == PERF_EVENT_STATE_OFF) |
6751b71e PM |
2527 | return 0; |
2528 | ||
fbbe0701 | 2529 | pmu->start_txn(pmu, PERF_PMU_TXN_ADD); |
6bde9b6c | 2530 | |
9ffcfa6f | 2531 | if (event_sched_in(group_event, cpuctx, ctx)) { |
ad5133b7 | 2532 | pmu->cancel_txn(pmu); |
272325c4 | 2533 | perf_mux_hrtimer_restart(cpuctx); |
6751b71e | 2534 | return -EAGAIN; |
90151c35 | 2535 | } |
6751b71e PM |
2536 | |
2537 | /* | |
2538 | * Schedule in siblings as one group (if any): | |
2539 | */ | |
edb39592 | 2540 | for_each_sibling_event(event, group_event) { |
9ffcfa6f | 2541 | if (event_sched_in(event, cpuctx, ctx)) { |
cdd6c482 | 2542 | partial_group = event; |
6751b71e PM |
2543 | goto group_error; |
2544 | } | |
2545 | } | |
2546 | ||
9ffcfa6f | 2547 | if (!pmu->commit_txn(pmu)) |
6e85158c | 2548 | return 0; |
9ffcfa6f | 2549 | |
6751b71e PM |
2550 | group_error: |
2551 | /* | |
2552 | * Groups can be scheduled in as one unit only, so undo any | |
2553 | * partial group before returning: | |
0d3d73aa | 2554 | * The events up to the failed event are scheduled out normally. |
6751b71e | 2555 | */ |
edb39592 | 2556 | for_each_sibling_event(event, group_event) { |
cdd6c482 | 2557 | if (event == partial_group) |
0d3d73aa | 2558 | break; |
d7842da4 | 2559 | |
0d3d73aa | 2560 | event_sched_out(event, cpuctx, ctx); |
6751b71e | 2561 | } |
9ffcfa6f | 2562 | event_sched_out(group_event, cpuctx, ctx); |
6751b71e | 2563 | |
ad5133b7 | 2564 | pmu->cancel_txn(pmu); |
90151c35 | 2565 | |
272325c4 | 2566 | perf_mux_hrtimer_restart(cpuctx); |
9e630205 | 2567 | |
6751b71e PM |
2568 | return -EAGAIN; |
2569 | } | |
2570 | ||
3b6f9e5c | 2571 | /* |
cdd6c482 | 2572 | * Work out whether we can put this event group on the CPU now. |
3b6f9e5c | 2573 | */ |
cdd6c482 | 2574 | static int group_can_go_on(struct perf_event *event, |
3b6f9e5c PM |
2575 | struct perf_cpu_context *cpuctx, |
2576 | int can_add_hw) | |
2577 | { | |
2578 | /* | |
cdd6c482 | 2579 | * Groups consisting entirely of software events can always go on. |
3b6f9e5c | 2580 | */ |
4ff6a8de | 2581 | if (event->group_caps & PERF_EV_CAP_SOFTWARE) |
3b6f9e5c PM |
2582 | return 1; |
2583 | /* | |
2584 | * If an exclusive group is already on, no other hardware | |
cdd6c482 | 2585 | * events can go on. |
3b6f9e5c PM |
2586 | */ |
2587 | if (cpuctx->exclusive) | |
2588 | return 0; | |
2589 | /* | |
2590 | * If this group is exclusive and there are already | |
cdd6c482 | 2591 | * events on the CPU, it can't go on. |
3b6f9e5c | 2592 | */ |
cdd6c482 | 2593 | if (event->attr.exclusive && cpuctx->active_oncpu) |
3b6f9e5c PM |
2594 | return 0; |
2595 | /* | |
2596 | * Otherwise, try to add it if all previous groups were able | |
2597 | * to go on. | |
2598 | */ | |
2599 | return can_add_hw; | |
2600 | } | |
2601 | ||
cdd6c482 IM |
2602 | static void add_event_to_ctx(struct perf_event *event, |
2603 | struct perf_event_context *ctx) | |
53cfbf59 | 2604 | { |
cdd6c482 | 2605 | list_add_event(event, ctx); |
8a49542c | 2606 | perf_group_attach(event); |
53cfbf59 PM |
2607 | } |
2608 | ||
bd2afa49 PZ |
2609 | static void ctx_sched_out(struct perf_event_context *ctx, |
2610 | struct perf_cpu_context *cpuctx, | |
2611 | enum event_type_t event_type); | |
2c29ef0f PZ |
2612 | static void |
2613 | ctx_sched_in(struct perf_event_context *ctx, | |
2614 | struct perf_cpu_context *cpuctx, | |
2615 | enum event_type_t event_type, | |
2616 | struct task_struct *task); | |
fe4b04fa | 2617 | |
bd2afa49 | 2618 | static void task_ctx_sched_out(struct perf_cpu_context *cpuctx, |
487f05e1 AS |
2619 | struct perf_event_context *ctx, |
2620 | enum event_type_t event_type) | |
bd2afa49 PZ |
2621 | { |
2622 | if (!cpuctx->task_ctx) | |
2623 | return; | |
2624 | ||
2625 | if (WARN_ON_ONCE(ctx != cpuctx->task_ctx)) | |
2626 | return; | |
2627 | ||
487f05e1 | 2628 | ctx_sched_out(ctx, cpuctx, event_type); |
bd2afa49 PZ |
2629 | } |
2630 | ||
dce5855b PZ |
2631 | static void perf_event_sched_in(struct perf_cpu_context *cpuctx, |
2632 | struct perf_event_context *ctx, | |
2633 | struct task_struct *task) | |
2634 | { | |
2635 | cpu_ctx_sched_in(cpuctx, EVENT_PINNED, task); | |
2636 | if (ctx) | |
2637 | ctx_sched_in(ctx, cpuctx, EVENT_PINNED, task); | |
2638 | cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE, task); | |
2639 | if (ctx) | |
2640 | ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE, task); | |
2641 | } | |
2642 | ||
487f05e1 AS |
2643 | /* |
2644 | * We want to maintain the following priority of scheduling: | |
2645 | * - CPU pinned (EVENT_CPU | EVENT_PINNED) | |
2646 | * - task pinned (EVENT_PINNED) | |
2647 | * - CPU flexible (EVENT_CPU | EVENT_FLEXIBLE) | |
2648 | * - task flexible (EVENT_FLEXIBLE). | |
2649 | * | |
2650 | * In order to avoid unscheduling and scheduling back in everything every | |
2651 | * time an event is added, only do it for the groups of equal priority and | |
2652 | * below. | |
2653 | * | |
2654 | * This can be called after a batch operation on task events, in which case | |
2655 | * event_type is a bit mask of the types of events involved. For CPU events, | |
2656 | * event_type is only either EVENT_PINNED or EVENT_FLEXIBLE. | |
2657 | */ | |
3e349507 | 2658 | static void ctx_resched(struct perf_cpu_context *cpuctx, |
487f05e1 AS |
2659 | struct perf_event_context *task_ctx, |
2660 | enum event_type_t event_type) | |
0017960f | 2661 | { |
bd903afe | 2662 | enum event_type_t ctx_event_type; |
487f05e1 AS |
2663 | bool cpu_event = !!(event_type & EVENT_CPU); |
2664 | ||
2665 | /* | |
2666 | * If pinned groups are involved, flexible groups also need to be | |
2667 | * scheduled out. | |
2668 | */ | |
2669 | if (event_type & EVENT_PINNED) | |
2670 | event_type |= EVENT_FLEXIBLE; | |
2671 | ||
bd903afe SL |
2672 | ctx_event_type = event_type & EVENT_ALL; |
2673 | ||
3e349507 PZ |
2674 | perf_pmu_disable(cpuctx->ctx.pmu); |
2675 | if (task_ctx) | |
487f05e1 AS |
2676 | task_ctx_sched_out(cpuctx, task_ctx, event_type); |
2677 | ||
2678 | /* | |
2679 | * Decide which cpu ctx groups to schedule out based on the types | |
2680 | * of events that caused rescheduling: | |
2681 | * - EVENT_CPU: schedule out corresponding groups; | |
2682 | * - EVENT_PINNED task events: schedule out EVENT_FLEXIBLE groups; | |
2683 | * - otherwise, do nothing more. | |
2684 | */ | |
2685 | if (cpu_event) | |
2686 | cpu_ctx_sched_out(cpuctx, ctx_event_type); | |
2687 | else if (ctx_event_type & EVENT_PINNED) | |
2688 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
2689 | ||
3e349507 PZ |
2690 | perf_event_sched_in(cpuctx, task_ctx, current); |
2691 | perf_pmu_enable(cpuctx->ctx.pmu); | |
0017960f PZ |
2692 | } |
2693 | ||
c68d224e SE |
2694 | void perf_pmu_resched(struct pmu *pmu) |
2695 | { | |
2696 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); | |
2697 | struct perf_event_context *task_ctx = cpuctx->task_ctx; | |
2698 | ||
2699 | perf_ctx_lock(cpuctx, task_ctx); | |
2700 | ctx_resched(cpuctx, task_ctx, EVENT_ALL|EVENT_CPU); | |
2701 | perf_ctx_unlock(cpuctx, task_ctx); | |
2702 | } | |
2703 | ||
0793a61d | 2704 | /* |
cdd6c482 | 2705 | * Cross CPU call to install and enable a performance event |
682076ae | 2706 | * |
a096309b PZ |
2707 | * Very similar to remote_function() + event_function() but cannot assume that |
2708 | * things like ctx->is_active and cpuctx->task_ctx are set. | |
0793a61d | 2709 | */ |
fe4b04fa | 2710 | static int __perf_install_in_context(void *info) |
0793a61d | 2711 | { |
a096309b PZ |
2712 | struct perf_event *event = info; |
2713 | struct perf_event_context *ctx = event->ctx; | |
108b02cf | 2714 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
2c29ef0f | 2715 | struct perf_event_context *task_ctx = cpuctx->task_ctx; |
63cae12b | 2716 | bool reprogram = true; |
a096309b | 2717 | int ret = 0; |
0793a61d | 2718 | |
63b6da39 | 2719 | raw_spin_lock(&cpuctx->ctx.lock); |
39a43640 | 2720 | if (ctx->task) { |
b58f6b0d PZ |
2721 | raw_spin_lock(&ctx->lock); |
2722 | task_ctx = ctx; | |
a096309b | 2723 | |
63cae12b | 2724 | reprogram = (ctx->task == current); |
b58f6b0d | 2725 | |
39a43640 | 2726 | /* |
63cae12b PZ |
2727 | * If the task is running, it must be running on this CPU, |
2728 | * otherwise we cannot reprogram things. | |
2729 | * | |
2730 | * If its not running, we don't care, ctx->lock will | |
2731 | * serialize against it becoming runnable. | |
39a43640 | 2732 | */ |
63cae12b PZ |
2733 | if (task_curr(ctx->task) && !reprogram) { |
2734 | ret = -ESRCH; | |
2735 | goto unlock; | |
2736 | } | |
a096309b | 2737 | |
63cae12b | 2738 | WARN_ON_ONCE(reprogram && cpuctx->task_ctx && cpuctx->task_ctx != ctx); |
63b6da39 PZ |
2739 | } else if (task_ctx) { |
2740 | raw_spin_lock(&task_ctx->lock); | |
2c29ef0f | 2741 | } |
b58f6b0d | 2742 | |
33801b94 | 2743 | #ifdef CONFIG_CGROUP_PERF |
2744 | if (is_cgroup_event(event)) { | |
2745 | /* | |
2746 | * If the current cgroup doesn't match the event's | |
2747 | * cgroup, we should not try to schedule it. | |
2748 | */ | |
2749 | struct perf_cgroup *cgrp = perf_cgroup_from_task(current, ctx); | |
2750 | reprogram = cgroup_is_descendant(cgrp->css.cgroup, | |
2751 | event->cgrp->css.cgroup); | |
2752 | } | |
2753 | #endif | |
2754 | ||
63cae12b | 2755 | if (reprogram) { |
a096309b PZ |
2756 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
2757 | add_event_to_ctx(event, ctx); | |
487f05e1 | 2758 | ctx_resched(cpuctx, task_ctx, get_event_type(event)); |
a096309b PZ |
2759 | } else { |
2760 | add_event_to_ctx(event, ctx); | |
2761 | } | |
2762 | ||
63b6da39 | 2763 | unlock: |
2c29ef0f | 2764 | perf_ctx_unlock(cpuctx, task_ctx); |
fe4b04fa | 2765 | |
a096309b | 2766 | return ret; |
0793a61d TG |
2767 | } |
2768 | ||
8a58ddae AS |
2769 | static bool exclusive_event_installable(struct perf_event *event, |
2770 | struct perf_event_context *ctx); | |
2771 | ||
0793a61d | 2772 | /* |
a096309b PZ |
2773 | * Attach a performance event to a context. |
2774 | * | |
2775 | * Very similar to event_function_call, see comment there. | |
0793a61d TG |
2776 | */ |
2777 | static void | |
cdd6c482 IM |
2778 | perf_install_in_context(struct perf_event_context *ctx, |
2779 | struct perf_event *event, | |
0793a61d TG |
2780 | int cpu) |
2781 | { | |
a096309b | 2782 | struct task_struct *task = READ_ONCE(ctx->task); |
39a43640 | 2783 | |
fe4b04fa PZ |
2784 | lockdep_assert_held(&ctx->mutex); |
2785 | ||
8a58ddae AS |
2786 | WARN_ON_ONCE(!exclusive_event_installable(event, ctx)); |
2787 | ||
0cda4c02 YZ |
2788 | if (event->cpu != -1) |
2789 | event->cpu = cpu; | |
c3f00c70 | 2790 | |
0b8f1e2e PZ |
2791 | /* |
2792 | * Ensures that if we can observe event->ctx, both the event and ctx | |
2793 | * will be 'complete'. See perf_iterate_sb_cpu(). | |
2794 | */ | |
2795 | smp_store_release(&event->ctx, ctx); | |
2796 | ||
db0503e4 PZ |
2797 | /* |
2798 | * perf_event_attr::disabled events will not run and can be initialized | |
2799 | * without IPI. Except when this is the first event for the context, in | |
2800 | * that case we need the magic of the IPI to set ctx->is_active. | |
2801 | * | |
2802 | * The IOC_ENABLE that is sure to follow the creation of a disabled | |
2803 | * event will issue the IPI and reprogram the hardware. | |
2804 | */ | |
2805 | if (__perf_effective_state(event) == PERF_EVENT_STATE_OFF && ctx->nr_events) { | |
2806 | raw_spin_lock_irq(&ctx->lock); | |
2807 | if (ctx->task == TASK_TOMBSTONE) { | |
2808 | raw_spin_unlock_irq(&ctx->lock); | |
2809 | return; | |
2810 | } | |
2811 | add_event_to_ctx(event, ctx); | |
2812 | raw_spin_unlock_irq(&ctx->lock); | |
2813 | return; | |
2814 | } | |
2815 | ||
a096309b PZ |
2816 | if (!task) { |
2817 | cpu_function_call(cpu, __perf_install_in_context, event); | |
2818 | return; | |
2819 | } | |
2820 | ||
2821 | /* | |
2822 | * Should not happen, we validate the ctx is still alive before calling. | |
2823 | */ | |
2824 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) | |
2825 | return; | |
2826 | ||
39a43640 PZ |
2827 | /* |
2828 | * Installing events is tricky because we cannot rely on ctx->is_active | |
2829 | * to be set in case this is the nr_events 0 -> 1 transition. | |
63cae12b PZ |
2830 | * |
2831 | * Instead we use task_curr(), which tells us if the task is running. | |
2832 | * However, since we use task_curr() outside of rq::lock, we can race | |
2833 | * against the actual state. This means the result can be wrong. | |
2834 | * | |
2835 | * If we get a false positive, we retry, this is harmless. | |
2836 | * | |
2837 | * If we get a false negative, things are complicated. If we are after | |
2838 | * perf_event_context_sched_in() ctx::lock will serialize us, and the | |
2839 | * value must be correct. If we're before, it doesn't matter since | |
2840 | * perf_event_context_sched_in() will program the counter. | |
2841 | * | |
2842 | * However, this hinges on the remote context switch having observed | |
2843 | * our task->perf_event_ctxp[] store, such that it will in fact take | |
2844 | * ctx::lock in perf_event_context_sched_in(). | |
2845 | * | |
2846 | * We do this by task_function_call(), if the IPI fails to hit the task | |
2847 | * we know any future context switch of task must see the | |
2848 | * perf_event_ctpx[] store. | |
39a43640 | 2849 | */ |
63cae12b | 2850 | |
63b6da39 | 2851 | /* |
63cae12b PZ |
2852 | * This smp_mb() orders the task->perf_event_ctxp[] store with the |
2853 | * task_cpu() load, such that if the IPI then does not find the task | |
2854 | * running, a future context switch of that task must observe the | |
2855 | * store. | |
63b6da39 | 2856 | */ |
63cae12b PZ |
2857 | smp_mb(); |
2858 | again: | |
2859 | if (!task_function_call(task, __perf_install_in_context, event)) | |
a096309b PZ |
2860 | return; |
2861 | ||
2862 | raw_spin_lock_irq(&ctx->lock); | |
2863 | task = ctx->task; | |
84c4e620 | 2864 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) { |
a096309b PZ |
2865 | /* |
2866 | * Cannot happen because we already checked above (which also | |
2867 | * cannot happen), and we hold ctx->mutex, which serializes us | |
2868 | * against perf_event_exit_task_context(). | |
2869 | */ | |
63b6da39 PZ |
2870 | raw_spin_unlock_irq(&ctx->lock); |
2871 | return; | |
2872 | } | |
39a43640 | 2873 | /* |
63cae12b PZ |
2874 | * If the task is not running, ctx->lock will avoid it becoming so, |
2875 | * thus we can safely install the event. | |
39a43640 | 2876 | */ |
63cae12b PZ |
2877 | if (task_curr(task)) { |
2878 | raw_spin_unlock_irq(&ctx->lock); | |
2879 | goto again; | |
2880 | } | |
2881 | add_event_to_ctx(event, ctx); | |
2882 | raw_spin_unlock_irq(&ctx->lock); | |
0793a61d TG |
2883 | } |
2884 | ||
d859e29f | 2885 | /* |
cdd6c482 | 2886 | * Cross CPU call to enable a performance event |
d859e29f | 2887 | */ |
fae3fde6 PZ |
2888 | static void __perf_event_enable(struct perf_event *event, |
2889 | struct perf_cpu_context *cpuctx, | |
2890 | struct perf_event_context *ctx, | |
2891 | void *info) | |
04289bb9 | 2892 | { |
cdd6c482 | 2893 | struct perf_event *leader = event->group_leader; |
fae3fde6 | 2894 | struct perf_event_context *task_ctx; |
04289bb9 | 2895 | |
6e801e01 PZ |
2896 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2897 | event->state <= PERF_EVENT_STATE_ERROR) | |
fae3fde6 | 2898 | return; |
3cbed429 | 2899 | |
bd2afa49 PZ |
2900 | if (ctx->is_active) |
2901 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); | |
2902 | ||
0d3d73aa | 2903 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
04289bb9 | 2904 | |
fae3fde6 PZ |
2905 | if (!ctx->is_active) |
2906 | return; | |
2907 | ||
e5d1367f | 2908 | if (!event_filter_match(event)) { |
bd2afa49 | 2909 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); |
fae3fde6 | 2910 | return; |
e5d1367f | 2911 | } |
f4c4176f | 2912 | |
04289bb9 | 2913 | /* |
cdd6c482 | 2914 | * If the event is in a group and isn't the group leader, |
d859e29f | 2915 | * then don't put it on unless the group is on. |
04289bb9 | 2916 | */ |
bd2afa49 PZ |
2917 | if (leader != event && leader->state != PERF_EVENT_STATE_ACTIVE) { |
2918 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
fae3fde6 | 2919 | return; |
bd2afa49 | 2920 | } |
fe4b04fa | 2921 | |
fae3fde6 PZ |
2922 | task_ctx = cpuctx->task_ctx; |
2923 | if (ctx->task) | |
2924 | WARN_ON_ONCE(task_ctx != ctx); | |
d859e29f | 2925 | |
487f05e1 | 2926 | ctx_resched(cpuctx, task_ctx, get_event_type(event)); |
7b648018 PZ |
2927 | } |
2928 | ||
d859e29f | 2929 | /* |
788faab7 | 2930 | * Enable an event. |
c93f7669 | 2931 | * |
cdd6c482 IM |
2932 | * If event->ctx is a cloned context, callers must make sure that |
2933 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 2934 | * remains valid. This condition is satisfied when called through |
cdd6c482 IM |
2935 | * perf_event_for_each_child or perf_event_for_each as described |
2936 | * for perf_event_disable. | |
d859e29f | 2937 | */ |
f63a8daa | 2938 | static void _perf_event_enable(struct perf_event *event) |
d859e29f | 2939 | { |
cdd6c482 | 2940 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 2941 | |
7b648018 | 2942 | raw_spin_lock_irq(&ctx->lock); |
6e801e01 PZ |
2943 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2944 | event->state < PERF_EVENT_STATE_ERROR) { | |
7b648018 | 2945 | raw_spin_unlock_irq(&ctx->lock); |
d859e29f PM |
2946 | return; |
2947 | } | |
2948 | ||
d859e29f | 2949 | /* |
cdd6c482 | 2950 | * If the event is in error state, clear that first. |
7b648018 PZ |
2951 | * |
2952 | * That way, if we see the event in error state below, we know that it | |
2953 | * has gone back into error state, as distinct from the task having | |
2954 | * been scheduled away before the cross-call arrived. | |
d859e29f | 2955 | */ |
cdd6c482 IM |
2956 | if (event->state == PERF_EVENT_STATE_ERROR) |
2957 | event->state = PERF_EVENT_STATE_OFF; | |
e625cce1 | 2958 | raw_spin_unlock_irq(&ctx->lock); |
fe4b04fa | 2959 | |
fae3fde6 | 2960 | event_function_call(event, __perf_event_enable, NULL); |
d859e29f | 2961 | } |
f63a8daa PZ |
2962 | |
2963 | /* | |
2964 | * See perf_event_disable(); | |
2965 | */ | |
2966 | void perf_event_enable(struct perf_event *event) | |
2967 | { | |
2968 | struct perf_event_context *ctx; | |
2969 | ||
2970 | ctx = perf_event_ctx_lock(event); | |
2971 | _perf_event_enable(event); | |
2972 | perf_event_ctx_unlock(event, ctx); | |
2973 | } | |
dcfce4a0 | 2974 | EXPORT_SYMBOL_GPL(perf_event_enable); |
d859e29f | 2975 | |
375637bc AS |
2976 | struct stop_event_data { |
2977 | struct perf_event *event; | |
2978 | unsigned int restart; | |
2979 | }; | |
2980 | ||
95ff4ca2 AS |
2981 | static int __perf_event_stop(void *info) |
2982 | { | |
375637bc AS |
2983 | struct stop_event_data *sd = info; |
2984 | struct perf_event *event = sd->event; | |
95ff4ca2 | 2985 | |
375637bc | 2986 | /* if it's already INACTIVE, do nothing */ |
95ff4ca2 AS |
2987 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) |
2988 | return 0; | |
2989 | ||
2990 | /* matches smp_wmb() in event_sched_in() */ | |
2991 | smp_rmb(); | |
2992 | ||
2993 | /* | |
2994 | * There is a window with interrupts enabled before we get here, | |
2995 | * so we need to check again lest we try to stop another CPU's event. | |
2996 | */ | |
2997 | if (READ_ONCE(event->oncpu) != smp_processor_id()) | |
2998 | return -EAGAIN; | |
2999 | ||
3000 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3001 | ||
375637bc AS |
3002 | /* |
3003 | * May race with the actual stop (through perf_pmu_output_stop()), | |
3004 | * but it is only used for events with AUX ring buffer, and such | |
3005 | * events will refuse to restart because of rb::aux_mmap_count==0, | |
3006 | * see comments in perf_aux_output_begin(). | |
3007 | * | |
788faab7 | 3008 | * Since this is happening on an event-local CPU, no trace is lost |
375637bc AS |
3009 | * while restarting. |
3010 | */ | |
3011 | if (sd->restart) | |
c9bbdd48 | 3012 | event->pmu->start(event, 0); |
375637bc | 3013 | |
95ff4ca2 AS |
3014 | return 0; |
3015 | } | |
3016 | ||
767ae086 | 3017 | static int perf_event_stop(struct perf_event *event, int restart) |
375637bc AS |
3018 | { |
3019 | struct stop_event_data sd = { | |
3020 | .event = event, | |
767ae086 | 3021 | .restart = restart, |
375637bc AS |
3022 | }; |
3023 | int ret = 0; | |
3024 | ||
3025 | do { | |
3026 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) | |
3027 | return 0; | |
3028 | ||
3029 | /* matches smp_wmb() in event_sched_in() */ | |
3030 | smp_rmb(); | |
3031 | ||
3032 | /* | |
3033 | * We only want to restart ACTIVE events, so if the event goes | |
3034 | * inactive here (event->oncpu==-1), there's nothing more to do; | |
3035 | * fall through with ret==-ENXIO. | |
3036 | */ | |
3037 | ret = cpu_function_call(READ_ONCE(event->oncpu), | |
3038 | __perf_event_stop, &sd); | |
3039 | } while (ret == -EAGAIN); | |
3040 | ||
3041 | return ret; | |
3042 | } | |
3043 | ||
3044 | /* | |
3045 | * In order to contain the amount of racy and tricky in the address filter | |
3046 | * configuration management, it is a two part process: | |
3047 | * | |
3048 | * (p1) when userspace mappings change as a result of (1) or (2) or (3) below, | |
3049 | * we update the addresses of corresponding vmas in | |
c60f83b8 | 3050 | * event::addr_filter_ranges array and bump the event::addr_filters_gen; |
375637bc AS |
3051 | * (p2) when an event is scheduled in (pmu::add), it calls |
3052 | * perf_event_addr_filters_sync() which calls pmu::addr_filters_sync() | |
3053 | * if the generation has changed since the previous call. | |
3054 | * | |
3055 | * If (p1) happens while the event is active, we restart it to force (p2). | |
3056 | * | |
3057 | * (1) perf_addr_filters_apply(): adjusting filters' offsets based on | |
3058 | * pre-existing mappings, called once when new filters arrive via SET_FILTER | |
3059 | * ioctl; | |
3060 | * (2) perf_addr_filters_adjust(): adjusting filters' offsets based on newly | |
3061 | * registered mapping, called for every new mmap(), with mm::mmap_sem down | |
3062 | * for reading; | |
3063 | * (3) perf_event_addr_filters_exec(): clearing filters' offsets in the process | |
3064 | * of exec. | |
3065 | */ | |
3066 | void perf_event_addr_filters_sync(struct perf_event *event) | |
3067 | { | |
3068 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
3069 | ||
3070 | if (!has_addr_filter(event)) | |
3071 | return; | |
3072 | ||
3073 | raw_spin_lock(&ifh->lock); | |
3074 | if (event->addr_filters_gen != event->hw.addr_filters_gen) { | |
3075 | event->pmu->addr_filters_sync(event); | |
3076 | event->hw.addr_filters_gen = event->addr_filters_gen; | |
3077 | } | |
3078 | raw_spin_unlock(&ifh->lock); | |
3079 | } | |
3080 | EXPORT_SYMBOL_GPL(perf_event_addr_filters_sync); | |
3081 | ||
f63a8daa | 3082 | static int _perf_event_refresh(struct perf_event *event, int refresh) |
79f14641 | 3083 | { |
2023b359 | 3084 | /* |
cdd6c482 | 3085 | * not supported on inherited events |
2023b359 | 3086 | */ |
2e939d1d | 3087 | if (event->attr.inherit || !is_sampling_event(event)) |
2023b359 PZ |
3088 | return -EINVAL; |
3089 | ||
cdd6c482 | 3090 | atomic_add(refresh, &event->event_limit); |
f63a8daa | 3091 | _perf_event_enable(event); |
2023b359 PZ |
3092 | |
3093 | return 0; | |
79f14641 | 3094 | } |
f63a8daa PZ |
3095 | |
3096 | /* | |
3097 | * See perf_event_disable() | |
3098 | */ | |
3099 | int perf_event_refresh(struct perf_event *event, int refresh) | |
3100 | { | |
3101 | struct perf_event_context *ctx; | |
3102 | int ret; | |
3103 | ||
3104 | ctx = perf_event_ctx_lock(event); | |
3105 | ret = _perf_event_refresh(event, refresh); | |
3106 | perf_event_ctx_unlock(event, ctx); | |
3107 | ||
3108 | return ret; | |
3109 | } | |
26ca5c11 | 3110 | EXPORT_SYMBOL_GPL(perf_event_refresh); |
79f14641 | 3111 | |
32ff77e8 MC |
3112 | static int perf_event_modify_breakpoint(struct perf_event *bp, |
3113 | struct perf_event_attr *attr) | |
3114 | { | |
3115 | int err; | |
3116 | ||
3117 | _perf_event_disable(bp); | |
3118 | ||
3119 | err = modify_user_hw_breakpoint_check(bp, attr, true); | |
32ff77e8 | 3120 | |
bf06278c | 3121 | if (!bp->attr.disabled) |
32ff77e8 | 3122 | _perf_event_enable(bp); |
bf06278c JO |
3123 | |
3124 | return err; | |
32ff77e8 MC |
3125 | } |
3126 | ||
3127 | static int perf_event_modify_attr(struct perf_event *event, | |
3128 | struct perf_event_attr *attr) | |
3129 | { | |
3130 | if (event->attr.type != attr->type) | |
3131 | return -EINVAL; | |
3132 | ||
3133 | switch (event->attr.type) { | |
3134 | case PERF_TYPE_BREAKPOINT: | |
3135 | return perf_event_modify_breakpoint(event, attr); | |
3136 | default: | |
3137 | /* Place holder for future additions. */ | |
3138 | return -EOPNOTSUPP; | |
3139 | } | |
3140 | } | |
3141 | ||
5b0311e1 FW |
3142 | static void ctx_sched_out(struct perf_event_context *ctx, |
3143 | struct perf_cpu_context *cpuctx, | |
3144 | enum event_type_t event_type) | |
235c7fc7 | 3145 | { |
6668128a | 3146 | struct perf_event *event, *tmp; |
db24d33e | 3147 | int is_active = ctx->is_active; |
235c7fc7 | 3148 | |
c994d613 | 3149 | lockdep_assert_held(&ctx->lock); |
235c7fc7 | 3150 | |
39a43640 PZ |
3151 | if (likely(!ctx->nr_events)) { |
3152 | /* | |
3153 | * See __perf_remove_from_context(). | |
3154 | */ | |
3155 | WARN_ON_ONCE(ctx->is_active); | |
3156 | if (ctx->task) | |
3157 | WARN_ON_ONCE(cpuctx->task_ctx); | |
facc4307 | 3158 | return; |
39a43640 PZ |
3159 | } |
3160 | ||
db24d33e | 3161 | ctx->is_active &= ~event_type; |
3cbaa590 PZ |
3162 | if (!(ctx->is_active & EVENT_ALL)) |
3163 | ctx->is_active = 0; | |
3164 | ||
63e30d3e PZ |
3165 | if (ctx->task) { |
3166 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
3167 | if (!ctx->is_active) | |
3168 | cpuctx->task_ctx = NULL; | |
3169 | } | |
facc4307 | 3170 | |
8fdc6539 PZ |
3171 | /* |
3172 | * Always update time if it was set; not only when it changes. | |
3173 | * Otherwise we can 'forget' to update time for any but the last | |
3174 | * context we sched out. For example: | |
3175 | * | |
3176 | * ctx_sched_out(.event_type = EVENT_FLEXIBLE) | |
3177 | * ctx_sched_out(.event_type = EVENT_PINNED) | |
3178 | * | |
3179 | * would only update time for the pinned events. | |
3180 | */ | |
3cbaa590 PZ |
3181 | if (is_active & EVENT_TIME) { |
3182 | /* update (and stop) ctx time */ | |
3183 | update_context_time(ctx); | |
3184 | update_cgrp_time_from_cpuctx(cpuctx); | |
3185 | } | |
3186 | ||
8fdc6539 PZ |
3187 | is_active ^= ctx->is_active; /* changed bits */ |
3188 | ||
3cbaa590 | 3189 | if (!ctx->nr_active || !(is_active & EVENT_ALL)) |
facc4307 | 3190 | return; |
5b0311e1 | 3191 | |
075e0b00 | 3192 | perf_pmu_disable(ctx->pmu); |
3cbaa590 | 3193 | if (is_active & EVENT_PINNED) { |
6668128a | 3194 | list_for_each_entry_safe(event, tmp, &ctx->pinned_active, active_list) |
889ff015 | 3195 | group_sched_out(event, cpuctx, ctx); |
9ed6060d | 3196 | } |
889ff015 | 3197 | |
3cbaa590 | 3198 | if (is_active & EVENT_FLEXIBLE) { |
6668128a | 3199 | list_for_each_entry_safe(event, tmp, &ctx->flexible_active, active_list) |
8c9ed8e1 | 3200 | group_sched_out(event, cpuctx, ctx); |
90c91dfb PZ |
3201 | |
3202 | /* | |
3203 | * Since we cleared EVENT_FLEXIBLE, also clear | |
3204 | * rotate_necessary, is will be reset by | |
3205 | * ctx_flexible_sched_in() when needed. | |
3206 | */ | |
3207 | ctx->rotate_necessary = 0; | |
9ed6060d | 3208 | } |
1b9a644f | 3209 | perf_pmu_enable(ctx->pmu); |
235c7fc7 IM |
3210 | } |
3211 | ||
564c2b21 | 3212 | /* |
5a3126d4 PZ |
3213 | * Test whether two contexts are equivalent, i.e. whether they have both been |
3214 | * cloned from the same version of the same context. | |
3215 | * | |
3216 | * Equivalence is measured using a generation number in the context that is | |
3217 | * incremented on each modification to it; see unclone_ctx(), list_add_event() | |
3218 | * and list_del_event(). | |
564c2b21 | 3219 | */ |
cdd6c482 IM |
3220 | static int context_equiv(struct perf_event_context *ctx1, |
3221 | struct perf_event_context *ctx2) | |
564c2b21 | 3222 | { |
211de6eb PZ |
3223 | lockdep_assert_held(&ctx1->lock); |
3224 | lockdep_assert_held(&ctx2->lock); | |
3225 | ||
5a3126d4 PZ |
3226 | /* Pinning disables the swap optimization */ |
3227 | if (ctx1->pin_count || ctx2->pin_count) | |
3228 | return 0; | |
3229 | ||
3230 | /* If ctx1 is the parent of ctx2 */ | |
3231 | if (ctx1 == ctx2->parent_ctx && ctx1->generation == ctx2->parent_gen) | |
3232 | return 1; | |
3233 | ||
3234 | /* If ctx2 is the parent of ctx1 */ | |
3235 | if (ctx1->parent_ctx == ctx2 && ctx1->parent_gen == ctx2->generation) | |
3236 | return 1; | |
3237 | ||
3238 | /* | |
3239 | * If ctx1 and ctx2 have the same parent; we flatten the parent | |
3240 | * hierarchy, see perf_event_init_context(). | |
3241 | */ | |
3242 | if (ctx1->parent_ctx && ctx1->parent_ctx == ctx2->parent_ctx && | |
3243 | ctx1->parent_gen == ctx2->parent_gen) | |
3244 | return 1; | |
3245 | ||
3246 | /* Unmatched */ | |
3247 | return 0; | |
564c2b21 PM |
3248 | } |
3249 | ||
cdd6c482 IM |
3250 | static void __perf_event_sync_stat(struct perf_event *event, |
3251 | struct perf_event *next_event) | |
bfbd3381 PZ |
3252 | { |
3253 | u64 value; | |
3254 | ||
cdd6c482 | 3255 | if (!event->attr.inherit_stat) |
bfbd3381 PZ |
3256 | return; |
3257 | ||
3258 | /* | |
cdd6c482 | 3259 | * Update the event value, we cannot use perf_event_read() |
bfbd3381 PZ |
3260 | * because we're in the middle of a context switch and have IRQs |
3261 | * disabled, which upsets smp_call_function_single(), however | |
cdd6c482 | 3262 | * we know the event must be on the current CPU, therefore we |
bfbd3381 PZ |
3263 | * don't need to use it. |
3264 | */ | |
0d3d73aa | 3265 | if (event->state == PERF_EVENT_STATE_ACTIVE) |
3dbebf15 | 3266 | event->pmu->read(event); |
bfbd3381 | 3267 | |
0d3d73aa | 3268 | perf_event_update_time(event); |
bfbd3381 PZ |
3269 | |
3270 | /* | |
cdd6c482 | 3271 | * In order to keep per-task stats reliable we need to flip the event |
bfbd3381 PZ |
3272 | * values when we flip the contexts. |
3273 | */ | |
e7850595 PZ |
3274 | value = local64_read(&next_event->count); |
3275 | value = local64_xchg(&event->count, value); | |
3276 | local64_set(&next_event->count, value); | |
bfbd3381 | 3277 | |
cdd6c482 IM |
3278 | swap(event->total_time_enabled, next_event->total_time_enabled); |
3279 | swap(event->total_time_running, next_event->total_time_running); | |
19d2e755 | 3280 | |
bfbd3381 | 3281 | /* |
19d2e755 | 3282 | * Since we swizzled the values, update the user visible data too. |
bfbd3381 | 3283 | */ |
cdd6c482 IM |
3284 | perf_event_update_userpage(event); |
3285 | perf_event_update_userpage(next_event); | |
bfbd3381 PZ |
3286 | } |
3287 | ||
cdd6c482 IM |
3288 | static void perf_event_sync_stat(struct perf_event_context *ctx, |
3289 | struct perf_event_context *next_ctx) | |
bfbd3381 | 3290 | { |
cdd6c482 | 3291 | struct perf_event *event, *next_event; |
bfbd3381 PZ |
3292 | |
3293 | if (!ctx->nr_stat) | |
3294 | return; | |
3295 | ||
02ffdbc8 PZ |
3296 | update_context_time(ctx); |
3297 | ||
cdd6c482 IM |
3298 | event = list_first_entry(&ctx->event_list, |
3299 | struct perf_event, event_entry); | |
bfbd3381 | 3300 | |
cdd6c482 IM |
3301 | next_event = list_first_entry(&next_ctx->event_list, |
3302 | struct perf_event, event_entry); | |
bfbd3381 | 3303 | |
cdd6c482 IM |
3304 | while (&event->event_entry != &ctx->event_list && |
3305 | &next_event->event_entry != &next_ctx->event_list) { | |
bfbd3381 | 3306 | |
cdd6c482 | 3307 | __perf_event_sync_stat(event, next_event); |
bfbd3381 | 3308 | |
cdd6c482 IM |
3309 | event = list_next_entry(event, event_entry); |
3310 | next_event = list_next_entry(next_event, event_entry); | |
bfbd3381 PZ |
3311 | } |
3312 | } | |
3313 | ||
fe4b04fa PZ |
3314 | static void perf_event_context_sched_out(struct task_struct *task, int ctxn, |
3315 | struct task_struct *next) | |
0793a61d | 3316 | { |
8dc85d54 | 3317 | struct perf_event_context *ctx = task->perf_event_ctxp[ctxn]; |
cdd6c482 | 3318 | struct perf_event_context *next_ctx; |
5a3126d4 | 3319 | struct perf_event_context *parent, *next_parent; |
108b02cf | 3320 | struct perf_cpu_context *cpuctx; |
c93f7669 | 3321 | int do_switch = 1; |
0793a61d | 3322 | |
108b02cf PZ |
3323 | if (likely(!ctx)) |
3324 | return; | |
10989fb2 | 3325 | |
108b02cf PZ |
3326 | cpuctx = __get_cpu_context(ctx); |
3327 | if (!cpuctx->task_ctx) | |
0793a61d TG |
3328 | return; |
3329 | ||
c93f7669 | 3330 | rcu_read_lock(); |
8dc85d54 | 3331 | next_ctx = next->perf_event_ctxp[ctxn]; |
5a3126d4 PZ |
3332 | if (!next_ctx) |
3333 | goto unlock; | |
3334 | ||
3335 | parent = rcu_dereference(ctx->parent_ctx); | |
3336 | next_parent = rcu_dereference(next_ctx->parent_ctx); | |
3337 | ||
3338 | /* If neither context have a parent context; they cannot be clones. */ | |
802c8a61 | 3339 | if (!parent && !next_parent) |
5a3126d4 PZ |
3340 | goto unlock; |
3341 | ||
3342 | if (next_parent == ctx || next_ctx == parent || next_parent == parent) { | |
c93f7669 PM |
3343 | /* |
3344 | * Looks like the two contexts are clones, so we might be | |
3345 | * able to optimize the context switch. We lock both | |
3346 | * contexts and check that they are clones under the | |
3347 | * lock (including re-checking that neither has been | |
3348 | * uncloned in the meantime). It doesn't matter which | |
3349 | * order we take the locks because no other cpu could | |
3350 | * be trying to lock both of these tasks. | |
3351 | */ | |
e625cce1 TG |
3352 | raw_spin_lock(&ctx->lock); |
3353 | raw_spin_lock_nested(&next_ctx->lock, SINGLE_DEPTH_NESTING); | |
c93f7669 | 3354 | if (context_equiv(ctx, next_ctx)) { |
c2b98a86 AB |
3355 | struct pmu *pmu = ctx->pmu; |
3356 | ||
63b6da39 PZ |
3357 | WRITE_ONCE(ctx->task, next); |
3358 | WRITE_ONCE(next_ctx->task, task); | |
5a158c3c | 3359 | |
c2b98a86 AB |
3360 | /* |
3361 | * PMU specific parts of task perf context can require | |
3362 | * additional synchronization. As an example of such | |
3363 | * synchronization see implementation details of Intel | |
3364 | * LBR call stack data profiling; | |
3365 | */ | |
3366 | if (pmu->swap_task_ctx) | |
3367 | pmu->swap_task_ctx(ctx, next_ctx); | |
3368 | else | |
3369 | swap(ctx->task_ctx_data, next_ctx->task_ctx_data); | |
5a158c3c | 3370 | |
63b6da39 PZ |
3371 | /* |
3372 | * RCU_INIT_POINTER here is safe because we've not | |
3373 | * modified the ctx and the above modification of | |
3374 | * ctx->task and ctx->task_ctx_data are immaterial | |
3375 | * since those values are always verified under | |
3376 | * ctx->lock which we're now holding. | |
3377 | */ | |
3378 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], next_ctx); | |
3379 | RCU_INIT_POINTER(next->perf_event_ctxp[ctxn], ctx); | |
3380 | ||
c93f7669 | 3381 | do_switch = 0; |
bfbd3381 | 3382 | |
cdd6c482 | 3383 | perf_event_sync_stat(ctx, next_ctx); |
c93f7669 | 3384 | } |
e625cce1 TG |
3385 | raw_spin_unlock(&next_ctx->lock); |
3386 | raw_spin_unlock(&ctx->lock); | |
564c2b21 | 3387 | } |
5a3126d4 | 3388 | unlock: |
c93f7669 | 3389 | rcu_read_unlock(); |
564c2b21 | 3390 | |
c93f7669 | 3391 | if (do_switch) { |
facc4307 | 3392 | raw_spin_lock(&ctx->lock); |
487f05e1 | 3393 | task_ctx_sched_out(cpuctx, ctx, EVENT_ALL); |
facc4307 | 3394 | raw_spin_unlock(&ctx->lock); |
c93f7669 | 3395 | } |
0793a61d TG |
3396 | } |
3397 | ||
e48c1788 PZ |
3398 | static DEFINE_PER_CPU(struct list_head, sched_cb_list); |
3399 | ||
ba532500 YZ |
3400 | void perf_sched_cb_dec(struct pmu *pmu) |
3401 | { | |
e48c1788 PZ |
3402 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
3403 | ||
ba532500 | 3404 | this_cpu_dec(perf_sched_cb_usages); |
e48c1788 PZ |
3405 | |
3406 | if (!--cpuctx->sched_cb_usage) | |
3407 | list_del(&cpuctx->sched_cb_entry); | |
ba532500 YZ |
3408 | } |
3409 | ||
e48c1788 | 3410 | |
ba532500 YZ |
3411 | void perf_sched_cb_inc(struct pmu *pmu) |
3412 | { | |
e48c1788 PZ |
3413 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
3414 | ||
3415 | if (!cpuctx->sched_cb_usage++) | |
3416 | list_add(&cpuctx->sched_cb_entry, this_cpu_ptr(&sched_cb_list)); | |
3417 | ||
ba532500 YZ |
3418 | this_cpu_inc(perf_sched_cb_usages); |
3419 | } | |
3420 | ||
3421 | /* | |
3422 | * This function provides the context switch callback to the lower code | |
3423 | * layer. It is invoked ONLY when the context switch callback is enabled. | |
09e61b4f PZ |
3424 | * |
3425 | * This callback is relevant even to per-cpu events; for example multi event | |
3426 | * PEBS requires this to provide PID/TID information. This requires we flush | |
3427 | * all queued PEBS records before we context switch to a new task. | |
ba532500 YZ |
3428 | */ |
3429 | static void perf_pmu_sched_task(struct task_struct *prev, | |
3430 | struct task_struct *next, | |
3431 | bool sched_in) | |
3432 | { | |
3433 | struct perf_cpu_context *cpuctx; | |
3434 | struct pmu *pmu; | |
ba532500 YZ |
3435 | |
3436 | if (prev == next) | |
3437 | return; | |
3438 | ||
e48c1788 | 3439 | list_for_each_entry(cpuctx, this_cpu_ptr(&sched_cb_list), sched_cb_entry) { |
1fd7e416 | 3440 | pmu = cpuctx->ctx.pmu; /* software PMUs will not have sched_task */ |
ba532500 | 3441 | |
e48c1788 PZ |
3442 | if (WARN_ON_ONCE(!pmu->sched_task)) |
3443 | continue; | |
ba532500 | 3444 | |
e48c1788 PZ |
3445 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
3446 | perf_pmu_disable(pmu); | |
ba532500 | 3447 | |
e48c1788 | 3448 | pmu->sched_task(cpuctx->task_ctx, sched_in); |
ba532500 | 3449 | |
e48c1788 PZ |
3450 | perf_pmu_enable(pmu); |
3451 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
ba532500 | 3452 | } |
ba532500 YZ |
3453 | } |
3454 | ||
45ac1403 AH |
3455 | static void perf_event_switch(struct task_struct *task, |
3456 | struct task_struct *next_prev, bool sched_in); | |
3457 | ||
8dc85d54 PZ |
3458 | #define for_each_task_context_nr(ctxn) \ |
3459 | for ((ctxn) = 0; (ctxn) < perf_nr_task_contexts; (ctxn)++) | |
3460 | ||
3461 | /* | |
3462 | * Called from scheduler to remove the events of the current task, | |
3463 | * with interrupts disabled. | |
3464 | * | |
3465 | * We stop each event and update the event value in event->count. | |
3466 | * | |
3467 | * This does not protect us against NMI, but disable() | |
3468 | * sets the disabled bit in the control field of event _before_ | |
3469 | * accessing the event control register. If a NMI hits, then it will | |
3470 | * not restart the event. | |
3471 | */ | |
ab0cce56 JO |
3472 | void __perf_event_task_sched_out(struct task_struct *task, |
3473 | struct task_struct *next) | |
8dc85d54 PZ |
3474 | { |
3475 | int ctxn; | |
3476 | ||
ba532500 YZ |
3477 | if (__this_cpu_read(perf_sched_cb_usages)) |
3478 | perf_pmu_sched_task(task, next, false); | |
3479 | ||
45ac1403 AH |
3480 | if (atomic_read(&nr_switch_events)) |
3481 | perf_event_switch(task, next, false); | |
3482 | ||
8dc85d54 PZ |
3483 | for_each_task_context_nr(ctxn) |
3484 | perf_event_context_sched_out(task, ctxn, next); | |
e5d1367f SE |
3485 | |
3486 | /* | |
3487 | * if cgroup events exist on this CPU, then we need | |
3488 | * to check if we have to switch out PMU state. | |
3489 | * cgroup event are system-wide mode only | |
3490 | */ | |
4a32fea9 | 3491 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) |
a8d757ef | 3492 | perf_cgroup_sched_out(task, next); |
8dc85d54 PZ |
3493 | } |
3494 | ||
5b0311e1 FW |
3495 | /* |
3496 | * Called with IRQs disabled | |
3497 | */ | |
3498 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, | |
3499 | enum event_type_t event_type) | |
3500 | { | |
3501 | ctx_sched_out(&cpuctx->ctx, cpuctx, event_type); | |
04289bb9 IM |
3502 | } |
3503 | ||
6eef8a71 | 3504 | static bool perf_less_group_idx(const void *l, const void *r) |
0793a61d | 3505 | { |
6eef8a71 IR |
3506 | const struct perf_event *le = l, *re = r; |
3507 | ||
3508 | return le->group_index < re->group_index; | |
3509 | } | |
3510 | ||
3511 | static void swap_ptr(void *l, void *r) | |
3512 | { | |
3513 | void **lp = l, **rp = r; | |
3514 | ||
3515 | swap(*lp, *rp); | |
3516 | } | |
3517 | ||
3518 | static const struct min_heap_callbacks perf_min_heap = { | |
3519 | .elem_size = sizeof(struct perf_event *), | |
3520 | .less = perf_less_group_idx, | |
3521 | .swp = swap_ptr, | |
3522 | }; | |
3523 | ||
3524 | static void __heap_add(struct min_heap *heap, struct perf_event *event) | |
3525 | { | |
3526 | struct perf_event **itrs = heap->data; | |
3527 | ||
3528 | if (event) { | |
3529 | itrs[heap->nr] = event; | |
3530 | heap->nr++; | |
3531 | } | |
3532 | } | |
3533 | ||
836196be IR |
3534 | static noinline int visit_groups_merge(struct perf_cpu_context *cpuctx, |
3535 | struct perf_event_groups *groups, int cpu, | |
6eef8a71 IR |
3536 | int (*func)(struct perf_event *, void *), |
3537 | void *data) | |
3538 | { | |
95ed6c70 IR |
3539 | #ifdef CONFIG_CGROUP_PERF |
3540 | struct cgroup_subsys_state *css = NULL; | |
3541 | #endif | |
6eef8a71 IR |
3542 | /* Space for per CPU and/or any CPU event iterators. */ |
3543 | struct perf_event *itrs[2]; | |
836196be IR |
3544 | struct min_heap event_heap; |
3545 | struct perf_event **evt; | |
1cac7b1a | 3546 | int ret; |
8e1a2031 | 3547 | |
836196be IR |
3548 | if (cpuctx) { |
3549 | event_heap = (struct min_heap){ | |
3550 | .data = cpuctx->heap, | |
3551 | .nr = 0, | |
3552 | .size = cpuctx->heap_size, | |
3553 | }; | |
c2283c93 IR |
3554 | |
3555 | lockdep_assert_held(&cpuctx->ctx.lock); | |
95ed6c70 IR |
3556 | |
3557 | #ifdef CONFIG_CGROUP_PERF | |
3558 | if (cpuctx->cgrp) | |
3559 | css = &cpuctx->cgrp->css; | |
3560 | #endif | |
836196be IR |
3561 | } else { |
3562 | event_heap = (struct min_heap){ | |
3563 | .data = itrs, | |
3564 | .nr = 0, | |
3565 | .size = ARRAY_SIZE(itrs), | |
3566 | }; | |
3567 | /* Events not within a CPU context may be on any CPU. */ | |
95ed6c70 | 3568 | __heap_add(&event_heap, perf_event_groups_first(groups, -1, NULL)); |
836196be IR |
3569 | } |
3570 | evt = event_heap.data; | |
3571 | ||
95ed6c70 IR |
3572 | __heap_add(&event_heap, perf_event_groups_first(groups, cpu, NULL)); |
3573 | ||
3574 | #ifdef CONFIG_CGROUP_PERF | |
3575 | for (; css; css = css->parent) | |
3576 | __heap_add(&event_heap, perf_event_groups_first(groups, cpu, css->cgroup)); | |
3577 | #endif | |
1cac7b1a | 3578 | |
6eef8a71 | 3579 | min_heapify_all(&event_heap, &perf_min_heap); |
1cac7b1a | 3580 | |
6eef8a71 | 3581 | while (event_heap.nr) { |
1cac7b1a PZ |
3582 | ret = func(*evt, data); |
3583 | if (ret) | |
3584 | return ret; | |
3585 | ||
3586 | *evt = perf_event_groups_next(*evt); | |
6eef8a71 IR |
3587 | if (*evt) |
3588 | min_heapify(&event_heap, 0, &perf_min_heap); | |
3589 | else | |
3590 | min_heap_pop(&event_heap, &perf_min_heap); | |
8e1a2031 | 3591 | } |
0793a61d | 3592 | |
1cac7b1a PZ |
3593 | return 0; |
3594 | } | |
3595 | ||
ab6f824c | 3596 | static int merge_sched_in(struct perf_event *event, void *data) |
1cac7b1a | 3597 | { |
2c2366c7 PZ |
3598 | struct perf_event_context *ctx = event->ctx; |
3599 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
3600 | int *can_add_hw = data; | |
ab6f824c | 3601 | |
1cac7b1a PZ |
3602 | if (event->state <= PERF_EVENT_STATE_OFF) |
3603 | return 0; | |
3604 | ||
3605 | if (!event_filter_match(event)) | |
3606 | return 0; | |
3607 | ||
2c2366c7 PZ |
3608 | if (group_can_go_on(event, cpuctx, *can_add_hw)) { |
3609 | if (!group_sched_in(event, cpuctx, ctx)) | |
ab6f824c | 3610 | list_add_tail(&event->active_list, get_event_list(event)); |
6668128a | 3611 | } |
1cac7b1a | 3612 | |
ab6f824c PZ |
3613 | if (event->state == PERF_EVENT_STATE_INACTIVE) { |
3614 | if (event->attr.pinned) | |
3615 | perf_event_set_state(event, PERF_EVENT_STATE_ERROR); | |
1cac7b1a | 3616 | |
2c2366c7 PZ |
3617 | *can_add_hw = 0; |
3618 | ctx->rotate_necessary = 1; | |
3b6f9e5c | 3619 | } |
1cac7b1a PZ |
3620 | |
3621 | return 0; | |
5b0311e1 FW |
3622 | } |
3623 | ||
3624 | static void | |
1cac7b1a PZ |
3625 | ctx_pinned_sched_in(struct perf_event_context *ctx, |
3626 | struct perf_cpu_context *cpuctx) | |
5b0311e1 | 3627 | { |
2c2366c7 | 3628 | int can_add_hw = 1; |
3b6f9e5c | 3629 | |
836196be IR |
3630 | if (ctx != &cpuctx->ctx) |
3631 | cpuctx = NULL; | |
3632 | ||
3633 | visit_groups_merge(cpuctx, &ctx->pinned_groups, | |
1cac7b1a | 3634 | smp_processor_id(), |
2c2366c7 | 3635 | merge_sched_in, &can_add_hw); |
1cac7b1a | 3636 | } |
8e1a2031 | 3637 | |
1cac7b1a PZ |
3638 | static void |
3639 | ctx_flexible_sched_in(struct perf_event_context *ctx, | |
3640 | struct perf_cpu_context *cpuctx) | |
3641 | { | |
2c2366c7 | 3642 | int can_add_hw = 1; |
0793a61d | 3643 | |
836196be IR |
3644 | if (ctx != &cpuctx->ctx) |
3645 | cpuctx = NULL; | |
3646 | ||
3647 | visit_groups_merge(cpuctx, &ctx->flexible_groups, | |
1cac7b1a | 3648 | smp_processor_id(), |
2c2366c7 | 3649 | merge_sched_in, &can_add_hw); |
5b0311e1 FW |
3650 | } |
3651 | ||
3652 | static void | |
3653 | ctx_sched_in(struct perf_event_context *ctx, | |
3654 | struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
3655 | enum event_type_t event_type, |
3656 | struct task_struct *task) | |
5b0311e1 | 3657 | { |
db24d33e | 3658 | int is_active = ctx->is_active; |
c994d613 PZ |
3659 | u64 now; |
3660 | ||
3661 | lockdep_assert_held(&ctx->lock); | |
e5d1367f | 3662 | |
5b0311e1 | 3663 | if (likely(!ctx->nr_events)) |
facc4307 | 3664 | return; |
5b0311e1 | 3665 | |
3cbaa590 | 3666 | ctx->is_active |= (event_type | EVENT_TIME); |
63e30d3e PZ |
3667 | if (ctx->task) { |
3668 | if (!is_active) | |
3669 | cpuctx->task_ctx = ctx; | |
3670 | else | |
3671 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
3672 | } | |
3673 | ||
3cbaa590 PZ |
3674 | is_active ^= ctx->is_active; /* changed bits */ |
3675 | ||
3676 | if (is_active & EVENT_TIME) { | |
3677 | /* start ctx time */ | |
3678 | now = perf_clock(); | |
3679 | ctx->timestamp = now; | |
3680 | perf_cgroup_set_timestamp(task, ctx); | |
3681 | } | |
3682 | ||
5b0311e1 FW |
3683 | /* |
3684 | * First go through the list and put on any pinned groups | |
3685 | * in order to give them the best chance of going on. | |
3686 | */ | |
3cbaa590 | 3687 | if (is_active & EVENT_PINNED) |
6e37738a | 3688 | ctx_pinned_sched_in(ctx, cpuctx); |
5b0311e1 FW |
3689 | |
3690 | /* Then walk through the lower prio flexible groups */ | |
3cbaa590 | 3691 | if (is_active & EVENT_FLEXIBLE) |
6e37738a | 3692 | ctx_flexible_sched_in(ctx, cpuctx); |
235c7fc7 IM |
3693 | } |
3694 | ||
329c0e01 | 3695 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, |
e5d1367f SE |
3696 | enum event_type_t event_type, |
3697 | struct task_struct *task) | |
329c0e01 FW |
3698 | { |
3699 | struct perf_event_context *ctx = &cpuctx->ctx; | |
3700 | ||
e5d1367f | 3701 | ctx_sched_in(ctx, cpuctx, event_type, task); |
329c0e01 FW |
3702 | } |
3703 | ||
e5d1367f SE |
3704 | static void perf_event_context_sched_in(struct perf_event_context *ctx, |
3705 | struct task_struct *task) | |
235c7fc7 | 3706 | { |
108b02cf | 3707 | struct perf_cpu_context *cpuctx; |
235c7fc7 | 3708 | |
108b02cf | 3709 | cpuctx = __get_cpu_context(ctx); |
329c0e01 FW |
3710 | if (cpuctx->task_ctx == ctx) |
3711 | return; | |
3712 | ||
facc4307 | 3713 | perf_ctx_lock(cpuctx, ctx); |
fdccc3fb | 3714 | /* |
3715 | * We must check ctx->nr_events while holding ctx->lock, such | |
3716 | * that we serialize against perf_install_in_context(). | |
3717 | */ | |
3718 | if (!ctx->nr_events) | |
3719 | goto unlock; | |
3720 | ||
1b9a644f | 3721 | perf_pmu_disable(ctx->pmu); |
329c0e01 FW |
3722 | /* |
3723 | * We want to keep the following priority order: | |
3724 | * cpu pinned (that don't need to move), task pinned, | |
3725 | * cpu flexible, task flexible. | |
fe45bafb AS |
3726 | * |
3727 | * However, if task's ctx is not carrying any pinned | |
3728 | * events, no need to flip the cpuctx's events around. | |
329c0e01 | 3729 | */ |
8e1a2031 | 3730 | if (!RB_EMPTY_ROOT(&ctx->pinned_groups.tree)) |
fe45bafb | 3731 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); |
63e30d3e | 3732 | perf_event_sched_in(cpuctx, ctx, task); |
facc4307 | 3733 | perf_pmu_enable(ctx->pmu); |
fdccc3fb | 3734 | |
3735 | unlock: | |
facc4307 | 3736 | perf_ctx_unlock(cpuctx, ctx); |
235c7fc7 IM |
3737 | } |
3738 | ||
8dc85d54 PZ |
3739 | /* |
3740 | * Called from scheduler to add the events of the current task | |
3741 | * with interrupts disabled. | |
3742 | * | |
3743 | * We restore the event value and then enable it. | |
3744 | * | |
3745 | * This does not protect us against NMI, but enable() | |
3746 | * sets the enabled bit in the control field of event _before_ | |
3747 | * accessing the event control register. If a NMI hits, then it will | |
3748 | * keep the event running. | |
3749 | */ | |
ab0cce56 JO |
3750 | void __perf_event_task_sched_in(struct task_struct *prev, |
3751 | struct task_struct *task) | |
8dc85d54 PZ |
3752 | { |
3753 | struct perf_event_context *ctx; | |
3754 | int ctxn; | |
3755 | ||
7e41d177 PZ |
3756 | /* |
3757 | * If cgroup events exist on this CPU, then we need to check if we have | |
3758 | * to switch in PMU state; cgroup event are system-wide mode only. | |
3759 | * | |
3760 | * Since cgroup events are CPU events, we must schedule these in before | |
3761 | * we schedule in the task events. | |
3762 | */ | |
3763 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) | |
3764 | perf_cgroup_sched_in(prev, task); | |
3765 | ||
8dc85d54 PZ |
3766 | for_each_task_context_nr(ctxn) { |
3767 | ctx = task->perf_event_ctxp[ctxn]; | |
3768 | if (likely(!ctx)) | |
3769 | continue; | |
3770 | ||
e5d1367f | 3771 | perf_event_context_sched_in(ctx, task); |
8dc85d54 | 3772 | } |
d010b332 | 3773 | |
45ac1403 AH |
3774 | if (atomic_read(&nr_switch_events)) |
3775 | perf_event_switch(task, prev, true); | |
3776 | ||
ba532500 YZ |
3777 | if (__this_cpu_read(perf_sched_cb_usages)) |
3778 | perf_pmu_sched_task(prev, task, true); | |
235c7fc7 IM |
3779 | } |
3780 | ||
abd50713 PZ |
3781 | static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count) |
3782 | { | |
3783 | u64 frequency = event->attr.sample_freq; | |
3784 | u64 sec = NSEC_PER_SEC; | |
3785 | u64 divisor, dividend; | |
3786 | ||
3787 | int count_fls, nsec_fls, frequency_fls, sec_fls; | |
3788 | ||
3789 | count_fls = fls64(count); | |
3790 | nsec_fls = fls64(nsec); | |
3791 | frequency_fls = fls64(frequency); | |
3792 | sec_fls = 30; | |
3793 | ||
3794 | /* | |
3795 | * We got @count in @nsec, with a target of sample_freq HZ | |
3796 | * the target period becomes: | |
3797 | * | |
3798 | * @count * 10^9 | |
3799 | * period = ------------------- | |
3800 | * @nsec * sample_freq | |
3801 | * | |
3802 | */ | |
3803 | ||
3804 | /* | |
3805 | * Reduce accuracy by one bit such that @a and @b converge | |
3806 | * to a similar magnitude. | |
3807 | */ | |
fe4b04fa | 3808 | #define REDUCE_FLS(a, b) \ |
abd50713 PZ |
3809 | do { \ |
3810 | if (a##_fls > b##_fls) { \ | |
3811 | a >>= 1; \ | |
3812 | a##_fls--; \ | |
3813 | } else { \ | |
3814 | b >>= 1; \ | |
3815 | b##_fls--; \ | |
3816 | } \ | |
3817 | } while (0) | |
3818 | ||
3819 | /* | |
3820 | * Reduce accuracy until either term fits in a u64, then proceed with | |
3821 | * the other, so that finally we can do a u64/u64 division. | |
3822 | */ | |
3823 | while (count_fls + sec_fls > 64 && nsec_fls + frequency_fls > 64) { | |
3824 | REDUCE_FLS(nsec, frequency); | |
3825 | REDUCE_FLS(sec, count); | |
3826 | } | |
3827 | ||
3828 | if (count_fls + sec_fls > 64) { | |
3829 | divisor = nsec * frequency; | |
3830 | ||
3831 | while (count_fls + sec_fls > 64) { | |
3832 | REDUCE_FLS(count, sec); | |
3833 | divisor >>= 1; | |
3834 | } | |
3835 | ||
3836 | dividend = count * sec; | |
3837 | } else { | |
3838 | dividend = count * sec; | |
3839 | ||
3840 | while (nsec_fls + frequency_fls > 64) { | |
3841 | REDUCE_FLS(nsec, frequency); | |
3842 | dividend >>= 1; | |
3843 | } | |
3844 | ||
3845 | divisor = nsec * frequency; | |
3846 | } | |
3847 | ||
f6ab91ad PZ |
3848 | if (!divisor) |
3849 | return dividend; | |
3850 | ||
abd50713 PZ |
3851 | return div64_u64(dividend, divisor); |
3852 | } | |
3853 | ||
e050e3f0 SE |
3854 | static DEFINE_PER_CPU(int, perf_throttled_count); |
3855 | static DEFINE_PER_CPU(u64, perf_throttled_seq); | |
3856 | ||
f39d47ff | 3857 | static void perf_adjust_period(struct perf_event *event, u64 nsec, u64 count, bool disable) |
bd2b5b12 | 3858 | { |
cdd6c482 | 3859 | struct hw_perf_event *hwc = &event->hw; |
f6ab91ad | 3860 | s64 period, sample_period; |
bd2b5b12 PZ |
3861 | s64 delta; |
3862 | ||
abd50713 | 3863 | period = perf_calculate_period(event, nsec, count); |
bd2b5b12 PZ |
3864 | |
3865 | delta = (s64)(period - hwc->sample_period); | |
3866 | delta = (delta + 7) / 8; /* low pass filter */ | |
3867 | ||
3868 | sample_period = hwc->sample_period + delta; | |
3869 | ||
3870 | if (!sample_period) | |
3871 | sample_period = 1; | |
3872 | ||
bd2b5b12 | 3873 | hwc->sample_period = sample_period; |
abd50713 | 3874 | |
e7850595 | 3875 | if (local64_read(&hwc->period_left) > 8*sample_period) { |
f39d47ff SE |
3876 | if (disable) |
3877 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3878 | ||
e7850595 | 3879 | local64_set(&hwc->period_left, 0); |
f39d47ff SE |
3880 | |
3881 | if (disable) | |
3882 | event->pmu->start(event, PERF_EF_RELOAD); | |
abd50713 | 3883 | } |
bd2b5b12 PZ |
3884 | } |
3885 | ||
e050e3f0 SE |
3886 | /* |
3887 | * combine freq adjustment with unthrottling to avoid two passes over the | |
3888 | * events. At the same time, make sure, having freq events does not change | |
3889 | * the rate of unthrottling as that would introduce bias. | |
3890 | */ | |
3891 | static void perf_adjust_freq_unthr_context(struct perf_event_context *ctx, | |
3892 | int needs_unthr) | |
60db5e09 | 3893 | { |
cdd6c482 IM |
3894 | struct perf_event *event; |
3895 | struct hw_perf_event *hwc; | |
e050e3f0 | 3896 | u64 now, period = TICK_NSEC; |
abd50713 | 3897 | s64 delta; |
60db5e09 | 3898 | |
e050e3f0 SE |
3899 | /* |
3900 | * only need to iterate over all events iff: | |
3901 | * - context have events in frequency mode (needs freq adjust) | |
3902 | * - there are events to unthrottle on this cpu | |
3903 | */ | |
3904 | if (!(ctx->nr_freq || needs_unthr)) | |
0f5a2601 PZ |
3905 | return; |
3906 | ||
e050e3f0 | 3907 | raw_spin_lock(&ctx->lock); |
f39d47ff | 3908 | perf_pmu_disable(ctx->pmu); |
e050e3f0 | 3909 | |
03541f8b | 3910 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { |
cdd6c482 | 3911 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
60db5e09 PZ |
3912 | continue; |
3913 | ||
5632ab12 | 3914 | if (!event_filter_match(event)) |
5d27c23d PZ |
3915 | continue; |
3916 | ||
44377277 AS |
3917 | perf_pmu_disable(event->pmu); |
3918 | ||
cdd6c482 | 3919 | hwc = &event->hw; |
6a24ed6c | 3920 | |
ae23bff1 | 3921 | if (hwc->interrupts == MAX_INTERRUPTS) { |
e050e3f0 | 3922 | hwc->interrupts = 0; |
cdd6c482 | 3923 | perf_log_throttle(event, 1); |
a4eaf7f1 | 3924 | event->pmu->start(event, 0); |
a78ac325 PZ |
3925 | } |
3926 | ||
cdd6c482 | 3927 | if (!event->attr.freq || !event->attr.sample_freq) |
44377277 | 3928 | goto next; |
60db5e09 | 3929 | |
e050e3f0 SE |
3930 | /* |
3931 | * stop the event and update event->count | |
3932 | */ | |
3933 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3934 | ||
e7850595 | 3935 | now = local64_read(&event->count); |
abd50713 PZ |
3936 | delta = now - hwc->freq_count_stamp; |
3937 | hwc->freq_count_stamp = now; | |
60db5e09 | 3938 | |
e050e3f0 SE |
3939 | /* |
3940 | * restart the event | |
3941 | * reload only if value has changed | |
f39d47ff SE |
3942 | * we have stopped the event so tell that |
3943 | * to perf_adjust_period() to avoid stopping it | |
3944 | * twice. | |
e050e3f0 | 3945 | */ |
abd50713 | 3946 | if (delta > 0) |
f39d47ff | 3947 | perf_adjust_period(event, period, delta, false); |
e050e3f0 SE |
3948 | |
3949 | event->pmu->start(event, delta > 0 ? PERF_EF_RELOAD : 0); | |
44377277 AS |
3950 | next: |
3951 | perf_pmu_enable(event->pmu); | |
60db5e09 | 3952 | } |
e050e3f0 | 3953 | |
f39d47ff | 3954 | perf_pmu_enable(ctx->pmu); |
e050e3f0 | 3955 | raw_spin_unlock(&ctx->lock); |
60db5e09 PZ |
3956 | } |
3957 | ||
235c7fc7 | 3958 | /* |
8703a7cf | 3959 | * Move @event to the tail of the @ctx's elegible events. |
235c7fc7 | 3960 | */ |
8703a7cf | 3961 | static void rotate_ctx(struct perf_event_context *ctx, struct perf_event *event) |
0793a61d | 3962 | { |
dddd3379 TG |
3963 | /* |
3964 | * Rotate the first entry last of non-pinned groups. Rotation might be | |
3965 | * disabled by the inheritance code. | |
3966 | */ | |
8703a7cf PZ |
3967 | if (ctx->rotate_disable) |
3968 | return; | |
8e1a2031 | 3969 | |
8703a7cf PZ |
3970 | perf_event_groups_delete(&ctx->flexible_groups, event); |
3971 | perf_event_groups_insert(&ctx->flexible_groups, event); | |
235c7fc7 IM |
3972 | } |
3973 | ||
7fa343b7 | 3974 | /* pick an event from the flexible_groups to rotate */ |
8d5bce0c | 3975 | static inline struct perf_event * |
7fa343b7 | 3976 | ctx_event_to_rotate(struct perf_event_context *ctx) |
235c7fc7 | 3977 | { |
7fa343b7 SL |
3978 | struct perf_event *event; |
3979 | ||
3980 | /* pick the first active flexible event */ | |
3981 | event = list_first_entry_or_null(&ctx->flexible_active, | |
3982 | struct perf_event, active_list); | |
3983 | ||
3984 | /* if no active flexible event, pick the first event */ | |
3985 | if (!event) { | |
3986 | event = rb_entry_safe(rb_first(&ctx->flexible_groups.tree), | |
3987 | typeof(*event), group_node); | |
3988 | } | |
3989 | ||
90c91dfb PZ |
3990 | /* |
3991 | * Unconditionally clear rotate_necessary; if ctx_flexible_sched_in() | |
3992 | * finds there are unschedulable events, it will set it again. | |
3993 | */ | |
3994 | ctx->rotate_necessary = 0; | |
3995 | ||
7fa343b7 | 3996 | return event; |
8d5bce0c PZ |
3997 | } |
3998 | ||
3999 | static bool perf_rotate_context(struct perf_cpu_context *cpuctx) | |
4000 | { | |
4001 | struct perf_event *cpu_event = NULL, *task_event = NULL; | |
fd7d5517 IR |
4002 | struct perf_event_context *task_ctx = NULL; |
4003 | int cpu_rotate, task_rotate; | |
8d5bce0c PZ |
4004 | |
4005 | /* | |
4006 | * Since we run this from IRQ context, nobody can install new | |
4007 | * events, thus the event count values are stable. | |
4008 | */ | |
7fc23a53 | 4009 | |
fd7d5517 IR |
4010 | cpu_rotate = cpuctx->ctx.rotate_necessary; |
4011 | task_ctx = cpuctx->task_ctx; | |
4012 | task_rotate = task_ctx ? task_ctx->rotate_necessary : 0; | |
9717e6cd | 4013 | |
8d5bce0c PZ |
4014 | if (!(cpu_rotate || task_rotate)) |
4015 | return false; | |
0f5a2601 | 4016 | |
facc4307 | 4017 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
1b9a644f | 4018 | perf_pmu_disable(cpuctx->ctx.pmu); |
60db5e09 | 4019 | |
8d5bce0c | 4020 | if (task_rotate) |
7fa343b7 | 4021 | task_event = ctx_event_to_rotate(task_ctx); |
8d5bce0c | 4022 | if (cpu_rotate) |
7fa343b7 | 4023 | cpu_event = ctx_event_to_rotate(&cpuctx->ctx); |
8703a7cf | 4024 | |
8d5bce0c PZ |
4025 | /* |
4026 | * As per the order given at ctx_resched() first 'pop' task flexible | |
4027 | * and then, if needed CPU flexible. | |
4028 | */ | |
fd7d5517 IR |
4029 | if (task_event || (task_ctx && cpu_event)) |
4030 | ctx_sched_out(task_ctx, cpuctx, EVENT_FLEXIBLE); | |
8d5bce0c PZ |
4031 | if (cpu_event) |
4032 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
0793a61d | 4033 | |
8d5bce0c | 4034 | if (task_event) |
fd7d5517 | 4035 | rotate_ctx(task_ctx, task_event); |
8d5bce0c PZ |
4036 | if (cpu_event) |
4037 | rotate_ctx(&cpuctx->ctx, cpu_event); | |
235c7fc7 | 4038 | |
fd7d5517 | 4039 | perf_event_sched_in(cpuctx, task_ctx, current); |
235c7fc7 | 4040 | |
0f5a2601 PZ |
4041 | perf_pmu_enable(cpuctx->ctx.pmu); |
4042 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
9e630205 | 4043 | |
8d5bce0c | 4044 | return true; |
e9d2b064 PZ |
4045 | } |
4046 | ||
4047 | void perf_event_task_tick(void) | |
4048 | { | |
2fde4f94 MR |
4049 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
4050 | struct perf_event_context *ctx, *tmp; | |
e050e3f0 | 4051 | int throttled; |
b5ab4cd5 | 4052 | |
16444645 | 4053 | lockdep_assert_irqs_disabled(); |
e9d2b064 | 4054 | |
e050e3f0 SE |
4055 | __this_cpu_inc(perf_throttled_seq); |
4056 | throttled = __this_cpu_xchg(perf_throttled_count, 0); | |
555e0c1e | 4057 | tick_dep_clear_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
e050e3f0 | 4058 | |
2fde4f94 | 4059 | list_for_each_entry_safe(ctx, tmp, head, active_ctx_list) |
e050e3f0 | 4060 | perf_adjust_freq_unthr_context(ctx, throttled); |
0793a61d TG |
4061 | } |
4062 | ||
889ff015 FW |
4063 | static int event_enable_on_exec(struct perf_event *event, |
4064 | struct perf_event_context *ctx) | |
4065 | { | |
4066 | if (!event->attr.enable_on_exec) | |
4067 | return 0; | |
4068 | ||
4069 | event->attr.enable_on_exec = 0; | |
4070 | if (event->state >= PERF_EVENT_STATE_INACTIVE) | |
4071 | return 0; | |
4072 | ||
0d3d73aa | 4073 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
889ff015 FW |
4074 | |
4075 | return 1; | |
4076 | } | |
4077 | ||
57e7986e | 4078 | /* |
cdd6c482 | 4079 | * Enable all of a task's events that have been marked enable-on-exec. |
57e7986e PM |
4080 | * This expects task == current. |
4081 | */ | |
c1274499 | 4082 | static void perf_event_enable_on_exec(int ctxn) |
57e7986e | 4083 | { |
c1274499 | 4084 | struct perf_event_context *ctx, *clone_ctx = NULL; |
487f05e1 | 4085 | enum event_type_t event_type = 0; |
3e349507 | 4086 | struct perf_cpu_context *cpuctx; |
cdd6c482 | 4087 | struct perf_event *event; |
57e7986e PM |
4088 | unsigned long flags; |
4089 | int enabled = 0; | |
4090 | ||
4091 | local_irq_save(flags); | |
c1274499 | 4092 | ctx = current->perf_event_ctxp[ctxn]; |
cdd6c482 | 4093 | if (!ctx || !ctx->nr_events) |
57e7986e PM |
4094 | goto out; |
4095 | ||
3e349507 PZ |
4096 | cpuctx = __get_cpu_context(ctx); |
4097 | perf_ctx_lock(cpuctx, ctx); | |
7fce2509 | 4098 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
487f05e1 | 4099 | list_for_each_entry(event, &ctx->event_list, event_entry) { |
3e349507 | 4100 | enabled |= event_enable_on_exec(event, ctx); |
487f05e1 AS |
4101 | event_type |= get_event_type(event); |
4102 | } | |
57e7986e PM |
4103 | |
4104 | /* | |
3e349507 | 4105 | * Unclone and reschedule this context if we enabled any event. |
57e7986e | 4106 | */ |
3e349507 | 4107 | if (enabled) { |
211de6eb | 4108 | clone_ctx = unclone_ctx(ctx); |
487f05e1 | 4109 | ctx_resched(cpuctx, ctx, event_type); |
7bbba0eb PZ |
4110 | } else { |
4111 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
3e349507 PZ |
4112 | } |
4113 | perf_ctx_unlock(cpuctx, ctx); | |
57e7986e | 4114 | |
9ed6060d | 4115 | out: |
57e7986e | 4116 | local_irq_restore(flags); |
211de6eb PZ |
4117 | |
4118 | if (clone_ctx) | |
4119 | put_ctx(clone_ctx); | |
57e7986e PM |
4120 | } |
4121 | ||
0492d4c5 PZ |
4122 | struct perf_read_data { |
4123 | struct perf_event *event; | |
4124 | bool group; | |
7d88962e | 4125 | int ret; |
0492d4c5 PZ |
4126 | }; |
4127 | ||
451d24d1 | 4128 | static int __perf_event_read_cpu(struct perf_event *event, int event_cpu) |
d6a2f903 | 4129 | { |
d6a2f903 DCC |
4130 | u16 local_pkg, event_pkg; |
4131 | ||
4132 | if (event->group_caps & PERF_EV_CAP_READ_ACTIVE_PKG) { | |
451d24d1 PZ |
4133 | int local_cpu = smp_processor_id(); |
4134 | ||
4135 | event_pkg = topology_physical_package_id(event_cpu); | |
4136 | local_pkg = topology_physical_package_id(local_cpu); | |
d6a2f903 DCC |
4137 | |
4138 | if (event_pkg == local_pkg) | |
4139 | return local_cpu; | |
4140 | } | |
4141 | ||
4142 | return event_cpu; | |
4143 | } | |
4144 | ||
0793a61d | 4145 | /* |
cdd6c482 | 4146 | * Cross CPU call to read the hardware event |
0793a61d | 4147 | */ |
cdd6c482 | 4148 | static void __perf_event_read(void *info) |
0793a61d | 4149 | { |
0492d4c5 PZ |
4150 | struct perf_read_data *data = info; |
4151 | struct perf_event *sub, *event = data->event; | |
cdd6c482 | 4152 | struct perf_event_context *ctx = event->ctx; |
108b02cf | 4153 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
4a00c16e | 4154 | struct pmu *pmu = event->pmu; |
621a01ea | 4155 | |
e1ac3614 PM |
4156 | /* |
4157 | * If this is a task context, we need to check whether it is | |
4158 | * the current task context of this cpu. If not it has been | |
4159 | * scheduled out before the smp call arrived. In that case | |
cdd6c482 IM |
4160 | * event->count would have been updated to a recent sample |
4161 | * when the event was scheduled out. | |
e1ac3614 PM |
4162 | */ |
4163 | if (ctx->task && cpuctx->task_ctx != ctx) | |
4164 | return; | |
4165 | ||
e625cce1 | 4166 | raw_spin_lock(&ctx->lock); |
0c1cbc18 | 4167 | if (ctx->is_active & EVENT_TIME) { |
542e72fc | 4168 | update_context_time(ctx); |
e5d1367f SE |
4169 | update_cgrp_time_from_event(event); |
4170 | } | |
0492d4c5 | 4171 | |
0d3d73aa PZ |
4172 | perf_event_update_time(event); |
4173 | if (data->group) | |
4174 | perf_event_update_sibling_time(event); | |
0c1cbc18 | 4175 | |
4a00c16e SB |
4176 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
4177 | goto unlock; | |
0492d4c5 | 4178 | |
4a00c16e SB |
4179 | if (!data->group) { |
4180 | pmu->read(event); | |
4181 | data->ret = 0; | |
0492d4c5 | 4182 | goto unlock; |
4a00c16e SB |
4183 | } |
4184 | ||
4185 | pmu->start_txn(pmu, PERF_PMU_TXN_READ); | |
4186 | ||
4187 | pmu->read(event); | |
0492d4c5 | 4188 | |
edb39592 | 4189 | for_each_sibling_event(sub, event) { |
4a00c16e SB |
4190 | if (sub->state == PERF_EVENT_STATE_ACTIVE) { |
4191 | /* | |
4192 | * Use sibling's PMU rather than @event's since | |
4193 | * sibling could be on different (eg: software) PMU. | |
4194 | */ | |
0492d4c5 | 4195 | sub->pmu->read(sub); |
4a00c16e | 4196 | } |
0492d4c5 | 4197 | } |
4a00c16e SB |
4198 | |
4199 | data->ret = pmu->commit_txn(pmu); | |
0492d4c5 PZ |
4200 | |
4201 | unlock: | |
e625cce1 | 4202 | raw_spin_unlock(&ctx->lock); |
0793a61d TG |
4203 | } |
4204 | ||
b5e58793 PZ |
4205 | static inline u64 perf_event_count(struct perf_event *event) |
4206 | { | |
c39a0e2c | 4207 | return local64_read(&event->count) + atomic64_read(&event->child_count); |
b5e58793 PZ |
4208 | } |
4209 | ||
ffe8690c KX |
4210 | /* |
4211 | * NMI-safe method to read a local event, that is an event that | |
4212 | * is: | |
4213 | * - either for the current task, or for this CPU | |
4214 | * - does not have inherit set, for inherited task events | |
4215 | * will not be local and we cannot read them atomically | |
4216 | * - must not have a pmu::count method | |
4217 | */ | |
7d9285e8 YS |
4218 | int perf_event_read_local(struct perf_event *event, u64 *value, |
4219 | u64 *enabled, u64 *running) | |
ffe8690c KX |
4220 | { |
4221 | unsigned long flags; | |
f91840a3 | 4222 | int ret = 0; |
ffe8690c KX |
4223 | |
4224 | /* | |
4225 | * Disabling interrupts avoids all counter scheduling (context | |
4226 | * switches, timer based rotation and IPIs). | |
4227 | */ | |
4228 | local_irq_save(flags); | |
4229 | ||
ffe8690c KX |
4230 | /* |
4231 | * It must not be an event with inherit set, we cannot read | |
4232 | * all child counters from atomic context. | |
4233 | */ | |
f91840a3 AS |
4234 | if (event->attr.inherit) { |
4235 | ret = -EOPNOTSUPP; | |
4236 | goto out; | |
4237 | } | |
ffe8690c | 4238 | |
f91840a3 AS |
4239 | /* If this is a per-task event, it must be for current */ |
4240 | if ((event->attach_state & PERF_ATTACH_TASK) && | |
4241 | event->hw.target != current) { | |
4242 | ret = -EINVAL; | |
4243 | goto out; | |
4244 | } | |
4245 | ||
4246 | /* If this is a per-CPU event, it must be for this CPU */ | |
4247 | if (!(event->attach_state & PERF_ATTACH_TASK) && | |
4248 | event->cpu != smp_processor_id()) { | |
4249 | ret = -EINVAL; | |
4250 | goto out; | |
4251 | } | |
ffe8690c | 4252 | |
befb1b3c RC |
4253 | /* If this is a pinned event it must be running on this CPU */ |
4254 | if (event->attr.pinned && event->oncpu != smp_processor_id()) { | |
4255 | ret = -EBUSY; | |
4256 | goto out; | |
4257 | } | |
4258 | ||
ffe8690c KX |
4259 | /* |
4260 | * If the event is currently on this CPU, its either a per-task event, | |
4261 | * or local to this CPU. Furthermore it means its ACTIVE (otherwise | |
4262 | * oncpu == -1). | |
4263 | */ | |
4264 | if (event->oncpu == smp_processor_id()) | |
4265 | event->pmu->read(event); | |
4266 | ||
f91840a3 | 4267 | *value = local64_read(&event->count); |
0d3d73aa PZ |
4268 | if (enabled || running) { |
4269 | u64 now = event->shadow_ctx_time + perf_clock(); | |
4270 | u64 __enabled, __running; | |
4271 | ||
4272 | __perf_update_times(event, now, &__enabled, &__running); | |
4273 | if (enabled) | |
4274 | *enabled = __enabled; | |
4275 | if (running) | |
4276 | *running = __running; | |
4277 | } | |
f91840a3 | 4278 | out: |
ffe8690c KX |
4279 | local_irq_restore(flags); |
4280 | ||
f91840a3 | 4281 | return ret; |
ffe8690c KX |
4282 | } |
4283 | ||
7d88962e | 4284 | static int perf_event_read(struct perf_event *event, bool group) |
0793a61d | 4285 | { |
0c1cbc18 | 4286 | enum perf_event_state state = READ_ONCE(event->state); |
451d24d1 | 4287 | int event_cpu, ret = 0; |
7d88962e | 4288 | |
0793a61d | 4289 | /* |
cdd6c482 IM |
4290 | * If event is enabled and currently active on a CPU, update the |
4291 | * value in the event structure: | |
0793a61d | 4292 | */ |
0c1cbc18 PZ |
4293 | again: |
4294 | if (state == PERF_EVENT_STATE_ACTIVE) { | |
4295 | struct perf_read_data data; | |
4296 | ||
4297 | /* | |
4298 | * Orders the ->state and ->oncpu loads such that if we see | |
4299 | * ACTIVE we must also see the right ->oncpu. | |
4300 | * | |
4301 | * Matches the smp_wmb() from event_sched_in(). | |
4302 | */ | |
4303 | smp_rmb(); | |
d6a2f903 | 4304 | |
451d24d1 PZ |
4305 | event_cpu = READ_ONCE(event->oncpu); |
4306 | if ((unsigned)event_cpu >= nr_cpu_ids) | |
4307 | return 0; | |
4308 | ||
0c1cbc18 PZ |
4309 | data = (struct perf_read_data){ |
4310 | .event = event, | |
4311 | .group = group, | |
4312 | .ret = 0, | |
4313 | }; | |
4314 | ||
451d24d1 PZ |
4315 | preempt_disable(); |
4316 | event_cpu = __perf_event_read_cpu(event, event_cpu); | |
d6a2f903 | 4317 | |
58763148 PZ |
4318 | /* |
4319 | * Purposely ignore the smp_call_function_single() return | |
4320 | * value. | |
4321 | * | |
451d24d1 | 4322 | * If event_cpu isn't a valid CPU it means the event got |
58763148 PZ |
4323 | * scheduled out and that will have updated the event count. |
4324 | * | |
4325 | * Therefore, either way, we'll have an up-to-date event count | |
4326 | * after this. | |
4327 | */ | |
451d24d1 PZ |
4328 | (void)smp_call_function_single(event_cpu, __perf_event_read, &data, 1); |
4329 | preempt_enable(); | |
58763148 | 4330 | ret = data.ret; |
0c1cbc18 PZ |
4331 | |
4332 | } else if (state == PERF_EVENT_STATE_INACTIVE) { | |
2b8988c9 PZ |
4333 | struct perf_event_context *ctx = event->ctx; |
4334 | unsigned long flags; | |
4335 | ||
e625cce1 | 4336 | raw_spin_lock_irqsave(&ctx->lock, flags); |
0c1cbc18 PZ |
4337 | state = event->state; |
4338 | if (state != PERF_EVENT_STATE_INACTIVE) { | |
4339 | raw_spin_unlock_irqrestore(&ctx->lock, flags); | |
4340 | goto again; | |
4341 | } | |
4342 | ||
c530ccd9 | 4343 | /* |
0c1cbc18 PZ |
4344 | * May read while context is not active (e.g., thread is |
4345 | * blocked), in that case we cannot update context time | |
c530ccd9 | 4346 | */ |
0c1cbc18 | 4347 | if (ctx->is_active & EVENT_TIME) { |
c530ccd9 | 4348 | update_context_time(ctx); |
e5d1367f SE |
4349 | update_cgrp_time_from_event(event); |
4350 | } | |
0c1cbc18 | 4351 | |
0d3d73aa | 4352 | perf_event_update_time(event); |
0492d4c5 | 4353 | if (group) |
0d3d73aa | 4354 | perf_event_update_sibling_time(event); |
e625cce1 | 4355 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
0793a61d | 4356 | } |
7d88962e SB |
4357 | |
4358 | return ret; | |
0793a61d TG |
4359 | } |
4360 | ||
a63eaf34 | 4361 | /* |
cdd6c482 | 4362 | * Initialize the perf_event context in a task_struct: |
a63eaf34 | 4363 | */ |
eb184479 | 4364 | static void __perf_event_init_context(struct perf_event_context *ctx) |
a63eaf34 | 4365 | { |
e625cce1 | 4366 | raw_spin_lock_init(&ctx->lock); |
a63eaf34 | 4367 | mutex_init(&ctx->mutex); |
2fde4f94 | 4368 | INIT_LIST_HEAD(&ctx->active_ctx_list); |
8e1a2031 AB |
4369 | perf_event_groups_init(&ctx->pinned_groups); |
4370 | perf_event_groups_init(&ctx->flexible_groups); | |
a63eaf34 | 4371 | INIT_LIST_HEAD(&ctx->event_list); |
6668128a PZ |
4372 | INIT_LIST_HEAD(&ctx->pinned_active); |
4373 | INIT_LIST_HEAD(&ctx->flexible_active); | |
8c94abbb | 4374 | refcount_set(&ctx->refcount, 1); |
eb184479 PZ |
4375 | } |
4376 | ||
4377 | static struct perf_event_context * | |
4378 | alloc_perf_context(struct pmu *pmu, struct task_struct *task) | |
4379 | { | |
4380 | struct perf_event_context *ctx; | |
4381 | ||
4382 | ctx = kzalloc(sizeof(struct perf_event_context), GFP_KERNEL); | |
4383 | if (!ctx) | |
4384 | return NULL; | |
4385 | ||
4386 | __perf_event_init_context(ctx); | |
7b3c92b8 MWO |
4387 | if (task) |
4388 | ctx->task = get_task_struct(task); | |
eb184479 PZ |
4389 | ctx->pmu = pmu; |
4390 | ||
4391 | return ctx; | |
a63eaf34 PM |
4392 | } |
4393 | ||
2ebd4ffb MH |
4394 | static struct task_struct * |
4395 | find_lively_task_by_vpid(pid_t vpid) | |
4396 | { | |
4397 | struct task_struct *task; | |
0793a61d TG |
4398 | |
4399 | rcu_read_lock(); | |
2ebd4ffb | 4400 | if (!vpid) |
0793a61d TG |
4401 | task = current; |
4402 | else | |
2ebd4ffb | 4403 | task = find_task_by_vpid(vpid); |
0793a61d TG |
4404 | if (task) |
4405 | get_task_struct(task); | |
4406 | rcu_read_unlock(); | |
4407 | ||
4408 | if (!task) | |
4409 | return ERR_PTR(-ESRCH); | |
4410 | ||
2ebd4ffb | 4411 | return task; |
2ebd4ffb MH |
4412 | } |
4413 | ||
fe4b04fa PZ |
4414 | /* |
4415 | * Returns a matching context with refcount and pincount. | |
4416 | */ | |
108b02cf | 4417 | static struct perf_event_context * |
4af57ef2 YZ |
4418 | find_get_context(struct pmu *pmu, struct task_struct *task, |
4419 | struct perf_event *event) | |
0793a61d | 4420 | { |
211de6eb | 4421 | struct perf_event_context *ctx, *clone_ctx = NULL; |
22a4f650 | 4422 | struct perf_cpu_context *cpuctx; |
4af57ef2 | 4423 | void *task_ctx_data = NULL; |
25346b93 | 4424 | unsigned long flags; |
8dc85d54 | 4425 | int ctxn, err; |
4af57ef2 | 4426 | int cpu = event->cpu; |
0793a61d | 4427 | |
22a4ec72 | 4428 | if (!task) { |
cdd6c482 | 4429 | /* Must be root to operate on a CPU event: */ |
da97e184 JFG |
4430 | err = perf_allow_cpu(&event->attr); |
4431 | if (err) | |
4432 | return ERR_PTR(err); | |
0793a61d | 4433 | |
108b02cf | 4434 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); |
0793a61d | 4435 | ctx = &cpuctx->ctx; |
c93f7669 | 4436 | get_ctx(ctx); |
fe4b04fa | 4437 | ++ctx->pin_count; |
0793a61d | 4438 | |
0793a61d TG |
4439 | return ctx; |
4440 | } | |
4441 | ||
8dc85d54 PZ |
4442 | err = -EINVAL; |
4443 | ctxn = pmu->task_ctx_nr; | |
4444 | if (ctxn < 0) | |
4445 | goto errout; | |
4446 | ||
4af57ef2 YZ |
4447 | if (event->attach_state & PERF_ATTACH_TASK_DATA) { |
4448 | task_ctx_data = kzalloc(pmu->task_ctx_size, GFP_KERNEL); | |
4449 | if (!task_ctx_data) { | |
4450 | err = -ENOMEM; | |
4451 | goto errout; | |
4452 | } | |
4453 | } | |
4454 | ||
9ed6060d | 4455 | retry: |
8dc85d54 | 4456 | ctx = perf_lock_task_context(task, ctxn, &flags); |
c93f7669 | 4457 | if (ctx) { |
211de6eb | 4458 | clone_ctx = unclone_ctx(ctx); |
fe4b04fa | 4459 | ++ctx->pin_count; |
4af57ef2 YZ |
4460 | |
4461 | if (task_ctx_data && !ctx->task_ctx_data) { | |
4462 | ctx->task_ctx_data = task_ctx_data; | |
4463 | task_ctx_data = NULL; | |
4464 | } | |
e625cce1 | 4465 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
211de6eb PZ |
4466 | |
4467 | if (clone_ctx) | |
4468 | put_ctx(clone_ctx); | |
9137fb28 | 4469 | } else { |
eb184479 | 4470 | ctx = alloc_perf_context(pmu, task); |
c93f7669 PM |
4471 | err = -ENOMEM; |
4472 | if (!ctx) | |
4473 | goto errout; | |
eb184479 | 4474 | |
4af57ef2 YZ |
4475 | if (task_ctx_data) { |
4476 | ctx->task_ctx_data = task_ctx_data; | |
4477 | task_ctx_data = NULL; | |
4478 | } | |
4479 | ||
dbe08d82 ON |
4480 | err = 0; |
4481 | mutex_lock(&task->perf_event_mutex); | |
4482 | /* | |
4483 | * If it has already passed perf_event_exit_task(). | |
4484 | * we must see PF_EXITING, it takes this mutex too. | |
4485 | */ | |
4486 | if (task->flags & PF_EXITING) | |
4487 | err = -ESRCH; | |
4488 | else if (task->perf_event_ctxp[ctxn]) | |
4489 | err = -EAGAIN; | |
fe4b04fa | 4490 | else { |
9137fb28 | 4491 | get_ctx(ctx); |
fe4b04fa | 4492 | ++ctx->pin_count; |
dbe08d82 | 4493 | rcu_assign_pointer(task->perf_event_ctxp[ctxn], ctx); |
fe4b04fa | 4494 | } |
dbe08d82 ON |
4495 | mutex_unlock(&task->perf_event_mutex); |
4496 | ||
4497 | if (unlikely(err)) { | |
9137fb28 | 4498 | put_ctx(ctx); |
dbe08d82 ON |
4499 | |
4500 | if (err == -EAGAIN) | |
4501 | goto retry; | |
4502 | goto errout; | |
a63eaf34 PM |
4503 | } |
4504 | } | |
4505 | ||
4af57ef2 | 4506 | kfree(task_ctx_data); |
0793a61d | 4507 | return ctx; |
c93f7669 | 4508 | |
9ed6060d | 4509 | errout: |
4af57ef2 | 4510 | kfree(task_ctx_data); |
c93f7669 | 4511 | return ERR_PTR(err); |
0793a61d TG |
4512 | } |
4513 | ||
6fb2915d | 4514 | static void perf_event_free_filter(struct perf_event *event); |
2541517c | 4515 | static void perf_event_free_bpf_prog(struct perf_event *event); |
6fb2915d | 4516 | |
cdd6c482 | 4517 | static void free_event_rcu(struct rcu_head *head) |
592903cd | 4518 | { |
cdd6c482 | 4519 | struct perf_event *event; |
592903cd | 4520 | |
cdd6c482 IM |
4521 | event = container_of(head, struct perf_event, rcu_head); |
4522 | if (event->ns) | |
4523 | put_pid_ns(event->ns); | |
6fb2915d | 4524 | perf_event_free_filter(event); |
cdd6c482 | 4525 | kfree(event); |
592903cd PZ |
4526 | } |
4527 | ||
b69cf536 | 4528 | static void ring_buffer_attach(struct perf_event *event, |
56de4e8f | 4529 | struct perf_buffer *rb); |
925d519a | 4530 | |
f2fb6bef KL |
4531 | static void detach_sb_event(struct perf_event *event) |
4532 | { | |
4533 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
4534 | ||
4535 | raw_spin_lock(&pel->lock); | |
4536 | list_del_rcu(&event->sb_list); | |
4537 | raw_spin_unlock(&pel->lock); | |
4538 | } | |
4539 | ||
a4f144eb | 4540 | static bool is_sb_event(struct perf_event *event) |
f2fb6bef | 4541 | { |
a4f144eb DCC |
4542 | struct perf_event_attr *attr = &event->attr; |
4543 | ||
f2fb6bef | 4544 | if (event->parent) |
a4f144eb | 4545 | return false; |
f2fb6bef KL |
4546 | |
4547 | if (event->attach_state & PERF_ATTACH_TASK) | |
a4f144eb | 4548 | return false; |
f2fb6bef | 4549 | |
a4f144eb DCC |
4550 | if (attr->mmap || attr->mmap_data || attr->mmap2 || |
4551 | attr->comm || attr->comm_exec || | |
76193a94 | 4552 | attr->task || attr->ksymbol || |
21038f2b SL |
4553 | attr->context_switch || |
4554 | attr->bpf_event) | |
a4f144eb DCC |
4555 | return true; |
4556 | return false; | |
4557 | } | |
4558 | ||
4559 | static void unaccount_pmu_sb_event(struct perf_event *event) | |
4560 | { | |
4561 | if (is_sb_event(event)) | |
4562 | detach_sb_event(event); | |
f2fb6bef KL |
4563 | } |
4564 | ||
4beb31f3 | 4565 | static void unaccount_event_cpu(struct perf_event *event, int cpu) |
f1600952 | 4566 | { |
4beb31f3 FW |
4567 | if (event->parent) |
4568 | return; | |
4569 | ||
4beb31f3 FW |
4570 | if (is_cgroup_event(event)) |
4571 | atomic_dec(&per_cpu(perf_cgroup_events, cpu)); | |
4572 | } | |
925d519a | 4573 | |
555e0c1e FW |
4574 | #ifdef CONFIG_NO_HZ_FULL |
4575 | static DEFINE_SPINLOCK(nr_freq_lock); | |
4576 | #endif | |
4577 | ||
4578 | static void unaccount_freq_event_nohz(void) | |
4579 | { | |
4580 | #ifdef CONFIG_NO_HZ_FULL | |
4581 | spin_lock(&nr_freq_lock); | |
4582 | if (atomic_dec_and_test(&nr_freq_events)) | |
4583 | tick_nohz_dep_clear(TICK_DEP_BIT_PERF_EVENTS); | |
4584 | spin_unlock(&nr_freq_lock); | |
4585 | #endif | |
4586 | } | |
4587 | ||
4588 | static void unaccount_freq_event(void) | |
4589 | { | |
4590 | if (tick_nohz_full_enabled()) | |
4591 | unaccount_freq_event_nohz(); | |
4592 | else | |
4593 | atomic_dec(&nr_freq_events); | |
4594 | } | |
4595 | ||
4beb31f3 FW |
4596 | static void unaccount_event(struct perf_event *event) |
4597 | { | |
25432ae9 PZ |
4598 | bool dec = false; |
4599 | ||
4beb31f3 FW |
4600 | if (event->parent) |
4601 | return; | |
4602 | ||
4603 | if (event->attach_state & PERF_ATTACH_TASK) | |
25432ae9 | 4604 | dec = true; |
4beb31f3 FW |
4605 | if (event->attr.mmap || event->attr.mmap_data) |
4606 | atomic_dec(&nr_mmap_events); | |
4607 | if (event->attr.comm) | |
4608 | atomic_dec(&nr_comm_events); | |
e4222673 HB |
4609 | if (event->attr.namespaces) |
4610 | atomic_dec(&nr_namespaces_events); | |
4beb31f3 FW |
4611 | if (event->attr.task) |
4612 | atomic_dec(&nr_task_events); | |
948b26b6 | 4613 | if (event->attr.freq) |
555e0c1e | 4614 | unaccount_freq_event(); |
45ac1403 | 4615 | if (event->attr.context_switch) { |
25432ae9 | 4616 | dec = true; |
45ac1403 AH |
4617 | atomic_dec(&nr_switch_events); |
4618 | } | |
4beb31f3 | 4619 | if (is_cgroup_event(event)) |
25432ae9 | 4620 | dec = true; |
4beb31f3 | 4621 | if (has_branch_stack(event)) |
25432ae9 | 4622 | dec = true; |
76193a94 SL |
4623 | if (event->attr.ksymbol) |
4624 | atomic_dec(&nr_ksymbol_events); | |
6ee52e2a SL |
4625 | if (event->attr.bpf_event) |
4626 | atomic_dec(&nr_bpf_events); | |
25432ae9 | 4627 | |
9107c89e PZ |
4628 | if (dec) { |
4629 | if (!atomic_add_unless(&perf_sched_count, -1, 1)) | |
4630 | schedule_delayed_work(&perf_sched_work, HZ); | |
4631 | } | |
4beb31f3 FW |
4632 | |
4633 | unaccount_event_cpu(event, event->cpu); | |
f2fb6bef KL |
4634 | |
4635 | unaccount_pmu_sb_event(event); | |
4beb31f3 | 4636 | } |
925d519a | 4637 | |
9107c89e PZ |
4638 | static void perf_sched_delayed(struct work_struct *work) |
4639 | { | |
4640 | mutex_lock(&perf_sched_mutex); | |
4641 | if (atomic_dec_and_test(&perf_sched_count)) | |
4642 | static_branch_disable(&perf_sched_events); | |
4643 | mutex_unlock(&perf_sched_mutex); | |
4644 | } | |
4645 | ||
bed5b25a AS |
4646 | /* |
4647 | * The following implement mutual exclusion of events on "exclusive" pmus | |
4648 | * (PERF_PMU_CAP_EXCLUSIVE). Such pmus can only have one event scheduled | |
4649 | * at a time, so we disallow creating events that might conflict, namely: | |
4650 | * | |
4651 | * 1) cpu-wide events in the presence of per-task events, | |
4652 | * 2) per-task events in the presence of cpu-wide events, | |
4653 | * 3) two matching events on the same context. | |
4654 | * | |
4655 | * The former two cases are handled in the allocation path (perf_event_alloc(), | |
a0733e69 | 4656 | * _free_event()), the latter -- before the first perf_install_in_context(). |
bed5b25a AS |
4657 | */ |
4658 | static int exclusive_event_init(struct perf_event *event) | |
4659 | { | |
4660 | struct pmu *pmu = event->pmu; | |
4661 | ||
8a58ddae | 4662 | if (!is_exclusive_pmu(pmu)) |
bed5b25a AS |
4663 | return 0; |
4664 | ||
4665 | /* | |
4666 | * Prevent co-existence of per-task and cpu-wide events on the | |
4667 | * same exclusive pmu. | |
4668 | * | |
4669 | * Negative pmu::exclusive_cnt means there are cpu-wide | |
4670 | * events on this "exclusive" pmu, positive means there are | |
4671 | * per-task events. | |
4672 | * | |
4673 | * Since this is called in perf_event_alloc() path, event::ctx | |
4674 | * doesn't exist yet; it is, however, safe to use PERF_ATTACH_TASK | |
4675 | * to mean "per-task event", because unlike other attach states it | |
4676 | * never gets cleared. | |
4677 | */ | |
4678 | if (event->attach_state & PERF_ATTACH_TASK) { | |
4679 | if (!atomic_inc_unless_negative(&pmu->exclusive_cnt)) | |
4680 | return -EBUSY; | |
4681 | } else { | |
4682 | if (!atomic_dec_unless_positive(&pmu->exclusive_cnt)) | |
4683 | return -EBUSY; | |
4684 | } | |
4685 | ||
4686 | return 0; | |
4687 | } | |
4688 | ||
4689 | static void exclusive_event_destroy(struct perf_event *event) | |
4690 | { | |
4691 | struct pmu *pmu = event->pmu; | |
4692 | ||
8a58ddae | 4693 | if (!is_exclusive_pmu(pmu)) |
bed5b25a AS |
4694 | return; |
4695 | ||
4696 | /* see comment in exclusive_event_init() */ | |
4697 | if (event->attach_state & PERF_ATTACH_TASK) | |
4698 | atomic_dec(&pmu->exclusive_cnt); | |
4699 | else | |
4700 | atomic_inc(&pmu->exclusive_cnt); | |
4701 | } | |
4702 | ||
4703 | static bool exclusive_event_match(struct perf_event *e1, struct perf_event *e2) | |
4704 | { | |
3bf6215a | 4705 | if ((e1->pmu == e2->pmu) && |
bed5b25a AS |
4706 | (e1->cpu == e2->cpu || |
4707 | e1->cpu == -1 || | |
4708 | e2->cpu == -1)) | |
4709 | return true; | |
4710 | return false; | |
4711 | } | |
4712 | ||
bed5b25a AS |
4713 | static bool exclusive_event_installable(struct perf_event *event, |
4714 | struct perf_event_context *ctx) | |
4715 | { | |
4716 | struct perf_event *iter_event; | |
4717 | struct pmu *pmu = event->pmu; | |
4718 | ||
8a58ddae AS |
4719 | lockdep_assert_held(&ctx->mutex); |
4720 | ||
4721 | if (!is_exclusive_pmu(pmu)) | |
bed5b25a AS |
4722 | return true; |
4723 | ||
4724 | list_for_each_entry(iter_event, &ctx->event_list, event_entry) { | |
4725 | if (exclusive_event_match(iter_event, event)) | |
4726 | return false; | |
4727 | } | |
4728 | ||
4729 | return true; | |
4730 | } | |
4731 | ||
375637bc AS |
4732 | static void perf_addr_filters_splice(struct perf_event *event, |
4733 | struct list_head *head); | |
4734 | ||
683ede43 | 4735 | static void _free_event(struct perf_event *event) |
f1600952 | 4736 | { |
e360adbe | 4737 | irq_work_sync(&event->pending); |
925d519a | 4738 | |
4beb31f3 | 4739 | unaccount_event(event); |
9ee318a7 | 4740 | |
da97e184 JFG |
4741 | security_perf_event_free(event); |
4742 | ||
76369139 | 4743 | if (event->rb) { |
9bb5d40c PZ |
4744 | /* |
4745 | * Can happen when we close an event with re-directed output. | |
4746 | * | |
4747 | * Since we have a 0 refcount, perf_mmap_close() will skip | |
4748 | * over us; possibly making our ring_buffer_put() the last. | |
4749 | */ | |
4750 | mutex_lock(&event->mmap_mutex); | |
b69cf536 | 4751 | ring_buffer_attach(event, NULL); |
9bb5d40c | 4752 | mutex_unlock(&event->mmap_mutex); |
a4be7c27 PZ |
4753 | } |
4754 | ||
e5d1367f SE |
4755 | if (is_cgroup_event(event)) |
4756 | perf_detach_cgroup(event); | |
4757 | ||
a0733e69 PZ |
4758 | if (!event->parent) { |
4759 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) | |
4760 | put_callchain_buffers(); | |
4761 | } | |
4762 | ||
4763 | perf_event_free_bpf_prog(event); | |
375637bc | 4764 | perf_addr_filters_splice(event, NULL); |
c60f83b8 | 4765 | kfree(event->addr_filter_ranges); |
a0733e69 PZ |
4766 | |
4767 | if (event->destroy) | |
4768 | event->destroy(event); | |
4769 | ||
1cf8dfe8 PZ |
4770 | /* |
4771 | * Must be after ->destroy(), due to uprobe_perf_close() using | |
4772 | * hw.target. | |
4773 | */ | |
621b6d2e PB |
4774 | if (event->hw.target) |
4775 | put_task_struct(event->hw.target); | |
4776 | ||
1cf8dfe8 PZ |
4777 | /* |
4778 | * perf_event_free_task() relies on put_ctx() being 'last', in particular | |
4779 | * all task references must be cleaned up. | |
4780 | */ | |
4781 | if (event->ctx) | |
4782 | put_ctx(event->ctx); | |
4783 | ||
62a92c8f AS |
4784 | exclusive_event_destroy(event); |
4785 | module_put(event->pmu->module); | |
a0733e69 PZ |
4786 | |
4787 | call_rcu(&event->rcu_head, free_event_rcu); | |
f1600952 PZ |
4788 | } |
4789 | ||
683ede43 PZ |
4790 | /* |
4791 | * Used to free events which have a known refcount of 1, such as in error paths | |
4792 | * where the event isn't exposed yet and inherited events. | |
4793 | */ | |
4794 | static void free_event(struct perf_event *event) | |
0793a61d | 4795 | { |
683ede43 PZ |
4796 | if (WARN(atomic_long_cmpxchg(&event->refcount, 1, 0) != 1, |
4797 | "unexpected event refcount: %ld; ptr=%p\n", | |
4798 | atomic_long_read(&event->refcount), event)) { | |
4799 | /* leak to avoid use-after-free */ | |
4800 | return; | |
4801 | } | |
0793a61d | 4802 | |
683ede43 | 4803 | _free_event(event); |
0793a61d TG |
4804 | } |
4805 | ||
a66a3052 | 4806 | /* |
f8697762 | 4807 | * Remove user event from the owner task. |
a66a3052 | 4808 | */ |
f8697762 | 4809 | static void perf_remove_from_owner(struct perf_event *event) |
fb0459d7 | 4810 | { |
8882135b | 4811 | struct task_struct *owner; |
fb0459d7 | 4812 | |
8882135b | 4813 | rcu_read_lock(); |
8882135b | 4814 | /* |
f47c02c0 PZ |
4815 | * Matches the smp_store_release() in perf_event_exit_task(). If we |
4816 | * observe !owner it means the list deletion is complete and we can | |
4817 | * indeed free this event, otherwise we need to serialize on | |
8882135b PZ |
4818 | * owner->perf_event_mutex. |
4819 | */ | |
506458ef | 4820 | owner = READ_ONCE(event->owner); |
8882135b PZ |
4821 | if (owner) { |
4822 | /* | |
4823 | * Since delayed_put_task_struct() also drops the last | |
4824 | * task reference we can safely take a new reference | |
4825 | * while holding the rcu_read_lock(). | |
4826 | */ | |
4827 | get_task_struct(owner); | |
4828 | } | |
4829 | rcu_read_unlock(); | |
4830 | ||
4831 | if (owner) { | |
f63a8daa PZ |
4832 | /* |
4833 | * If we're here through perf_event_exit_task() we're already | |
4834 | * holding ctx->mutex which would be an inversion wrt. the | |
4835 | * normal lock order. | |
4836 | * | |
4837 | * However we can safely take this lock because its the child | |
4838 | * ctx->mutex. | |
4839 | */ | |
4840 | mutex_lock_nested(&owner->perf_event_mutex, SINGLE_DEPTH_NESTING); | |
4841 | ||
8882135b PZ |
4842 | /* |
4843 | * We have to re-check the event->owner field, if it is cleared | |
4844 | * we raced with perf_event_exit_task(), acquiring the mutex | |
4845 | * ensured they're done, and we can proceed with freeing the | |
4846 | * event. | |
4847 | */ | |
f47c02c0 | 4848 | if (event->owner) { |
8882135b | 4849 | list_del_init(&event->owner_entry); |
f47c02c0 PZ |
4850 | smp_store_release(&event->owner, NULL); |
4851 | } | |
8882135b PZ |
4852 | mutex_unlock(&owner->perf_event_mutex); |
4853 | put_task_struct(owner); | |
4854 | } | |
f8697762 JO |
4855 | } |
4856 | ||
f8697762 JO |
4857 | static void put_event(struct perf_event *event) |
4858 | { | |
f8697762 JO |
4859 | if (!atomic_long_dec_and_test(&event->refcount)) |
4860 | return; | |
4861 | ||
c6e5b732 PZ |
4862 | _free_event(event); |
4863 | } | |
4864 | ||
4865 | /* | |
4866 | * Kill an event dead; while event:refcount will preserve the event | |
4867 | * object, it will not preserve its functionality. Once the last 'user' | |
4868 | * gives up the object, we'll destroy the thing. | |
4869 | */ | |
4870 | int perf_event_release_kernel(struct perf_event *event) | |
4871 | { | |
a4f4bb6d | 4872 | struct perf_event_context *ctx = event->ctx; |
c6e5b732 | 4873 | struct perf_event *child, *tmp; |
82d94856 | 4874 | LIST_HEAD(free_list); |
c6e5b732 | 4875 | |
a4f4bb6d PZ |
4876 | /* |
4877 | * If we got here through err_file: fput(event_file); we will not have | |
4878 | * attached to a context yet. | |
4879 | */ | |
4880 | if (!ctx) { | |
4881 | WARN_ON_ONCE(event->attach_state & | |
4882 | (PERF_ATTACH_CONTEXT|PERF_ATTACH_GROUP)); | |
4883 | goto no_ctx; | |
4884 | } | |
4885 | ||
f8697762 JO |
4886 | if (!is_kernel_event(event)) |
4887 | perf_remove_from_owner(event); | |
8882135b | 4888 | |
5fa7c8ec | 4889 | ctx = perf_event_ctx_lock(event); |
a83fe28e | 4890 | WARN_ON_ONCE(ctx->parent_ctx); |
a69b0ca4 | 4891 | perf_remove_from_context(event, DETACH_GROUP); |
683ede43 | 4892 | |
a69b0ca4 | 4893 | raw_spin_lock_irq(&ctx->lock); |
683ede43 | 4894 | /* |
d8a8cfc7 | 4895 | * Mark this event as STATE_DEAD, there is no external reference to it |
a69b0ca4 | 4896 | * anymore. |
683ede43 | 4897 | * |
a69b0ca4 PZ |
4898 | * Anybody acquiring event->child_mutex after the below loop _must_ |
4899 | * also see this, most importantly inherit_event() which will avoid | |
4900 | * placing more children on the list. | |
683ede43 | 4901 | * |
c6e5b732 PZ |
4902 | * Thus this guarantees that we will in fact observe and kill _ALL_ |
4903 | * child events. | |
683ede43 | 4904 | */ |
a69b0ca4 PZ |
4905 | event->state = PERF_EVENT_STATE_DEAD; |
4906 | raw_spin_unlock_irq(&ctx->lock); | |
4907 | ||
4908 | perf_event_ctx_unlock(event, ctx); | |
683ede43 | 4909 | |
c6e5b732 PZ |
4910 | again: |
4911 | mutex_lock(&event->child_mutex); | |
4912 | list_for_each_entry(child, &event->child_list, child_list) { | |
a6fa941d | 4913 | |
c6e5b732 PZ |
4914 | /* |
4915 | * Cannot change, child events are not migrated, see the | |
4916 | * comment with perf_event_ctx_lock_nested(). | |
4917 | */ | |
506458ef | 4918 | ctx = READ_ONCE(child->ctx); |
c6e5b732 PZ |
4919 | /* |
4920 | * Since child_mutex nests inside ctx::mutex, we must jump | |
4921 | * through hoops. We start by grabbing a reference on the ctx. | |
4922 | * | |
4923 | * Since the event cannot get freed while we hold the | |
4924 | * child_mutex, the context must also exist and have a !0 | |
4925 | * reference count. | |
4926 | */ | |
4927 | get_ctx(ctx); | |
4928 | ||
4929 | /* | |
4930 | * Now that we have a ctx ref, we can drop child_mutex, and | |
4931 | * acquire ctx::mutex without fear of it going away. Then we | |
4932 | * can re-acquire child_mutex. | |
4933 | */ | |
4934 | mutex_unlock(&event->child_mutex); | |
4935 | mutex_lock(&ctx->mutex); | |
4936 | mutex_lock(&event->child_mutex); | |
4937 | ||
4938 | /* | |
4939 | * Now that we hold ctx::mutex and child_mutex, revalidate our | |
4940 | * state, if child is still the first entry, it didn't get freed | |
4941 | * and we can continue doing so. | |
4942 | */ | |
4943 | tmp = list_first_entry_or_null(&event->child_list, | |
4944 | struct perf_event, child_list); | |
4945 | if (tmp == child) { | |
4946 | perf_remove_from_context(child, DETACH_GROUP); | |
82d94856 | 4947 | list_move(&child->child_list, &free_list); |
c6e5b732 PZ |
4948 | /* |
4949 | * This matches the refcount bump in inherit_event(); | |
4950 | * this can't be the last reference. | |
4951 | */ | |
4952 | put_event(event); | |
4953 | } | |
4954 | ||
4955 | mutex_unlock(&event->child_mutex); | |
4956 | mutex_unlock(&ctx->mutex); | |
4957 | put_ctx(ctx); | |
4958 | goto again; | |
4959 | } | |
4960 | mutex_unlock(&event->child_mutex); | |
4961 | ||
82d94856 | 4962 | list_for_each_entry_safe(child, tmp, &free_list, child_list) { |
1cf8dfe8 PZ |
4963 | void *var = &child->ctx->refcount; |
4964 | ||
82d94856 PZ |
4965 | list_del(&child->child_list); |
4966 | free_event(child); | |
1cf8dfe8 PZ |
4967 | |
4968 | /* | |
4969 | * Wake any perf_event_free_task() waiting for this event to be | |
4970 | * freed. | |
4971 | */ | |
4972 | smp_mb(); /* pairs with wait_var_event() */ | |
4973 | wake_up_var(var); | |
82d94856 PZ |
4974 | } |
4975 | ||
a4f4bb6d PZ |
4976 | no_ctx: |
4977 | put_event(event); /* Must be the 'last' reference */ | |
683ede43 PZ |
4978 | return 0; |
4979 | } | |
4980 | EXPORT_SYMBOL_GPL(perf_event_release_kernel); | |
4981 | ||
8b10c5e2 PZ |
4982 | /* |
4983 | * Called when the last reference to the file is gone. | |
4984 | */ | |
a6fa941d AV |
4985 | static int perf_release(struct inode *inode, struct file *file) |
4986 | { | |
c6e5b732 | 4987 | perf_event_release_kernel(file->private_data); |
a6fa941d | 4988 | return 0; |
fb0459d7 | 4989 | } |
fb0459d7 | 4990 | |
ca0dd44c | 4991 | static u64 __perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) |
e53c0994 | 4992 | { |
cdd6c482 | 4993 | struct perf_event *child; |
e53c0994 PZ |
4994 | u64 total = 0; |
4995 | ||
59ed446f PZ |
4996 | *enabled = 0; |
4997 | *running = 0; | |
4998 | ||
6f10581a | 4999 | mutex_lock(&event->child_mutex); |
01add3ea | 5000 | |
7d88962e | 5001 | (void)perf_event_read(event, false); |
01add3ea SB |
5002 | total += perf_event_count(event); |
5003 | ||
59ed446f PZ |
5004 | *enabled += event->total_time_enabled + |
5005 | atomic64_read(&event->child_total_time_enabled); | |
5006 | *running += event->total_time_running + | |
5007 | atomic64_read(&event->child_total_time_running); | |
5008 | ||
5009 | list_for_each_entry(child, &event->child_list, child_list) { | |
7d88962e | 5010 | (void)perf_event_read(child, false); |
01add3ea | 5011 | total += perf_event_count(child); |
59ed446f PZ |
5012 | *enabled += child->total_time_enabled; |
5013 | *running += child->total_time_running; | |
5014 | } | |
6f10581a | 5015 | mutex_unlock(&event->child_mutex); |
e53c0994 PZ |
5016 | |
5017 | return total; | |
5018 | } | |
ca0dd44c PZ |
5019 | |
5020 | u64 perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) | |
5021 | { | |
5022 | struct perf_event_context *ctx; | |
5023 | u64 count; | |
5024 | ||
5025 | ctx = perf_event_ctx_lock(event); | |
5026 | count = __perf_event_read_value(event, enabled, running); | |
5027 | perf_event_ctx_unlock(event, ctx); | |
5028 | ||
5029 | return count; | |
5030 | } | |
fb0459d7 | 5031 | EXPORT_SYMBOL_GPL(perf_event_read_value); |
e53c0994 | 5032 | |
7d88962e | 5033 | static int __perf_read_group_add(struct perf_event *leader, |
fa8c2693 | 5034 | u64 read_format, u64 *values) |
3dab77fb | 5035 | { |
2aeb1883 | 5036 | struct perf_event_context *ctx = leader->ctx; |
fa8c2693 | 5037 | struct perf_event *sub; |
2aeb1883 | 5038 | unsigned long flags; |
fa8c2693 | 5039 | int n = 1; /* skip @nr */ |
7d88962e | 5040 | int ret; |
f63a8daa | 5041 | |
7d88962e SB |
5042 | ret = perf_event_read(leader, true); |
5043 | if (ret) | |
5044 | return ret; | |
abf4868b | 5045 | |
a9cd8194 PZ |
5046 | raw_spin_lock_irqsave(&ctx->lock, flags); |
5047 | ||
fa8c2693 PZ |
5048 | /* |
5049 | * Since we co-schedule groups, {enabled,running} times of siblings | |
5050 | * will be identical to those of the leader, so we only publish one | |
5051 | * set. | |
5052 | */ | |
5053 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { | |
5054 | values[n++] += leader->total_time_enabled + | |
5055 | atomic64_read(&leader->child_total_time_enabled); | |
5056 | } | |
3dab77fb | 5057 | |
fa8c2693 PZ |
5058 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { |
5059 | values[n++] += leader->total_time_running + | |
5060 | atomic64_read(&leader->child_total_time_running); | |
5061 | } | |
5062 | ||
5063 | /* | |
5064 | * Write {count,id} tuples for every sibling. | |
5065 | */ | |
5066 | values[n++] += perf_event_count(leader); | |
abf4868b PZ |
5067 | if (read_format & PERF_FORMAT_ID) |
5068 | values[n++] = primary_event_id(leader); | |
3dab77fb | 5069 | |
edb39592 | 5070 | for_each_sibling_event(sub, leader) { |
fa8c2693 PZ |
5071 | values[n++] += perf_event_count(sub); |
5072 | if (read_format & PERF_FORMAT_ID) | |
5073 | values[n++] = primary_event_id(sub); | |
5074 | } | |
7d88962e | 5075 | |
2aeb1883 | 5076 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
7d88962e | 5077 | return 0; |
fa8c2693 | 5078 | } |
3dab77fb | 5079 | |
fa8c2693 PZ |
5080 | static int perf_read_group(struct perf_event *event, |
5081 | u64 read_format, char __user *buf) | |
5082 | { | |
5083 | struct perf_event *leader = event->group_leader, *child; | |
5084 | struct perf_event_context *ctx = leader->ctx; | |
7d88962e | 5085 | int ret; |
fa8c2693 | 5086 | u64 *values; |
3dab77fb | 5087 | |
fa8c2693 | 5088 | lockdep_assert_held(&ctx->mutex); |
3dab77fb | 5089 | |
fa8c2693 PZ |
5090 | values = kzalloc(event->read_size, GFP_KERNEL); |
5091 | if (!values) | |
5092 | return -ENOMEM; | |
3dab77fb | 5093 | |
fa8c2693 PZ |
5094 | values[0] = 1 + leader->nr_siblings; |
5095 | ||
5096 | /* | |
5097 | * By locking the child_mutex of the leader we effectively | |
5098 | * lock the child list of all siblings.. XXX explain how. | |
5099 | */ | |
5100 | mutex_lock(&leader->child_mutex); | |
abf4868b | 5101 | |
7d88962e SB |
5102 | ret = __perf_read_group_add(leader, read_format, values); |
5103 | if (ret) | |
5104 | goto unlock; | |
5105 | ||
5106 | list_for_each_entry(child, &leader->child_list, child_list) { | |
5107 | ret = __perf_read_group_add(child, read_format, values); | |
5108 | if (ret) | |
5109 | goto unlock; | |
5110 | } | |
abf4868b | 5111 | |
fa8c2693 | 5112 | mutex_unlock(&leader->child_mutex); |
abf4868b | 5113 | |
7d88962e | 5114 | ret = event->read_size; |
fa8c2693 PZ |
5115 | if (copy_to_user(buf, values, event->read_size)) |
5116 | ret = -EFAULT; | |
7d88962e | 5117 | goto out; |
fa8c2693 | 5118 | |
7d88962e SB |
5119 | unlock: |
5120 | mutex_unlock(&leader->child_mutex); | |
5121 | out: | |
fa8c2693 | 5122 | kfree(values); |
abf4868b | 5123 | return ret; |
3dab77fb PZ |
5124 | } |
5125 | ||
b15f495b | 5126 | static int perf_read_one(struct perf_event *event, |
3dab77fb PZ |
5127 | u64 read_format, char __user *buf) |
5128 | { | |
59ed446f | 5129 | u64 enabled, running; |
3dab77fb PZ |
5130 | u64 values[4]; |
5131 | int n = 0; | |
5132 | ||
ca0dd44c | 5133 | values[n++] = __perf_event_read_value(event, &enabled, &running); |
59ed446f PZ |
5134 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) |
5135 | values[n++] = enabled; | |
5136 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
5137 | values[n++] = running; | |
3dab77fb | 5138 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 5139 | values[n++] = primary_event_id(event); |
3dab77fb PZ |
5140 | |
5141 | if (copy_to_user(buf, values, n * sizeof(u64))) | |
5142 | return -EFAULT; | |
5143 | ||
5144 | return n * sizeof(u64); | |
5145 | } | |
5146 | ||
dc633982 JO |
5147 | static bool is_event_hup(struct perf_event *event) |
5148 | { | |
5149 | bool no_children; | |
5150 | ||
a69b0ca4 | 5151 | if (event->state > PERF_EVENT_STATE_EXIT) |
dc633982 JO |
5152 | return false; |
5153 | ||
5154 | mutex_lock(&event->child_mutex); | |
5155 | no_children = list_empty(&event->child_list); | |
5156 | mutex_unlock(&event->child_mutex); | |
5157 | return no_children; | |
5158 | } | |
5159 | ||
0793a61d | 5160 | /* |
cdd6c482 | 5161 | * Read the performance event - simple non blocking version for now |
0793a61d TG |
5162 | */ |
5163 | static ssize_t | |
b15f495b | 5164 | __perf_read(struct perf_event *event, char __user *buf, size_t count) |
0793a61d | 5165 | { |
cdd6c482 | 5166 | u64 read_format = event->attr.read_format; |
3dab77fb | 5167 | int ret; |
0793a61d | 5168 | |
3b6f9e5c | 5169 | /* |
788faab7 | 5170 | * Return end-of-file for a read on an event that is in |
3b6f9e5c PM |
5171 | * error state (i.e. because it was pinned but it couldn't be |
5172 | * scheduled on to the CPU at some point). | |
5173 | */ | |
cdd6c482 | 5174 | if (event->state == PERF_EVENT_STATE_ERROR) |
3b6f9e5c PM |
5175 | return 0; |
5176 | ||
c320c7b7 | 5177 | if (count < event->read_size) |
3dab77fb PZ |
5178 | return -ENOSPC; |
5179 | ||
cdd6c482 | 5180 | WARN_ON_ONCE(event->ctx->parent_ctx); |
3dab77fb | 5181 | if (read_format & PERF_FORMAT_GROUP) |
b15f495b | 5182 | ret = perf_read_group(event, read_format, buf); |
3dab77fb | 5183 | else |
b15f495b | 5184 | ret = perf_read_one(event, read_format, buf); |
0793a61d | 5185 | |
3dab77fb | 5186 | return ret; |
0793a61d TG |
5187 | } |
5188 | ||
0793a61d TG |
5189 | static ssize_t |
5190 | perf_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) | |
5191 | { | |
cdd6c482 | 5192 | struct perf_event *event = file->private_data; |
f63a8daa PZ |
5193 | struct perf_event_context *ctx; |
5194 | int ret; | |
0793a61d | 5195 | |
da97e184 JFG |
5196 | ret = security_perf_event_read(event); |
5197 | if (ret) | |
5198 | return ret; | |
5199 | ||
f63a8daa | 5200 | ctx = perf_event_ctx_lock(event); |
b15f495b | 5201 | ret = __perf_read(event, buf, count); |
f63a8daa PZ |
5202 | perf_event_ctx_unlock(event, ctx); |
5203 | ||
5204 | return ret; | |
0793a61d TG |
5205 | } |
5206 | ||
9dd95748 | 5207 | static __poll_t perf_poll(struct file *file, poll_table *wait) |
0793a61d | 5208 | { |
cdd6c482 | 5209 | struct perf_event *event = file->private_data; |
56de4e8f | 5210 | struct perf_buffer *rb; |
a9a08845 | 5211 | __poll_t events = EPOLLHUP; |
c7138f37 | 5212 | |
e708d7ad | 5213 | poll_wait(file, &event->waitq, wait); |
179033b3 | 5214 | |
dc633982 | 5215 | if (is_event_hup(event)) |
179033b3 | 5216 | return events; |
c7138f37 | 5217 | |
10c6db11 | 5218 | /* |
9bb5d40c PZ |
5219 | * Pin the event->rb by taking event->mmap_mutex; otherwise |
5220 | * perf_event_set_output() can swizzle our rb and make us miss wakeups. | |
10c6db11 PZ |
5221 | */ |
5222 | mutex_lock(&event->mmap_mutex); | |
9bb5d40c PZ |
5223 | rb = event->rb; |
5224 | if (rb) | |
76369139 | 5225 | events = atomic_xchg(&rb->poll, 0); |
10c6db11 | 5226 | mutex_unlock(&event->mmap_mutex); |
0793a61d TG |
5227 | return events; |
5228 | } | |
5229 | ||
f63a8daa | 5230 | static void _perf_event_reset(struct perf_event *event) |
6de6a7b9 | 5231 | { |
7d88962e | 5232 | (void)perf_event_read(event, false); |
e7850595 | 5233 | local64_set(&event->count, 0); |
cdd6c482 | 5234 | perf_event_update_userpage(event); |
3df5edad PZ |
5235 | } |
5236 | ||
52ba4b0b LX |
5237 | /* Assume it's not an event with inherit set. */ |
5238 | u64 perf_event_pause(struct perf_event *event, bool reset) | |
5239 | { | |
5240 | struct perf_event_context *ctx; | |
5241 | u64 count; | |
5242 | ||
5243 | ctx = perf_event_ctx_lock(event); | |
5244 | WARN_ON_ONCE(event->attr.inherit); | |
5245 | _perf_event_disable(event); | |
5246 | count = local64_read(&event->count); | |
5247 | if (reset) | |
5248 | local64_set(&event->count, 0); | |
5249 | perf_event_ctx_unlock(event, ctx); | |
5250 | ||
5251 | return count; | |
5252 | } | |
5253 | EXPORT_SYMBOL_GPL(perf_event_pause); | |
5254 | ||
c93f7669 | 5255 | /* |
cdd6c482 IM |
5256 | * Holding the top-level event's child_mutex means that any |
5257 | * descendant process that has inherited this event will block | |
8ba289b8 | 5258 | * in perf_event_exit_event() if it goes to exit, thus satisfying the |
cdd6c482 | 5259 | * task existence requirements of perf_event_enable/disable. |
c93f7669 | 5260 | */ |
cdd6c482 IM |
5261 | static void perf_event_for_each_child(struct perf_event *event, |
5262 | void (*func)(struct perf_event *)) | |
3df5edad | 5263 | { |
cdd6c482 | 5264 | struct perf_event *child; |
3df5edad | 5265 | |
cdd6c482 | 5266 | WARN_ON_ONCE(event->ctx->parent_ctx); |
f63a8daa | 5267 | |
cdd6c482 IM |
5268 | mutex_lock(&event->child_mutex); |
5269 | func(event); | |
5270 | list_for_each_entry(child, &event->child_list, child_list) | |
3df5edad | 5271 | func(child); |
cdd6c482 | 5272 | mutex_unlock(&event->child_mutex); |
3df5edad PZ |
5273 | } |
5274 | ||
cdd6c482 IM |
5275 | static void perf_event_for_each(struct perf_event *event, |
5276 | void (*func)(struct perf_event *)) | |
3df5edad | 5277 | { |
cdd6c482 IM |
5278 | struct perf_event_context *ctx = event->ctx; |
5279 | struct perf_event *sibling; | |
3df5edad | 5280 | |
f63a8daa PZ |
5281 | lockdep_assert_held(&ctx->mutex); |
5282 | ||
cdd6c482 | 5283 | event = event->group_leader; |
75f937f2 | 5284 | |
cdd6c482 | 5285 | perf_event_for_each_child(event, func); |
edb39592 | 5286 | for_each_sibling_event(sibling, event) |
724b6daa | 5287 | perf_event_for_each_child(sibling, func); |
6de6a7b9 PZ |
5288 | } |
5289 | ||
fae3fde6 PZ |
5290 | static void __perf_event_period(struct perf_event *event, |
5291 | struct perf_cpu_context *cpuctx, | |
5292 | struct perf_event_context *ctx, | |
5293 | void *info) | |
c7999c6f | 5294 | { |
fae3fde6 | 5295 | u64 value = *((u64 *)info); |
c7999c6f | 5296 | bool active; |
08247e31 | 5297 | |
cdd6c482 | 5298 | if (event->attr.freq) { |
cdd6c482 | 5299 | event->attr.sample_freq = value; |
08247e31 | 5300 | } else { |
cdd6c482 IM |
5301 | event->attr.sample_period = value; |
5302 | event->hw.sample_period = value; | |
08247e31 | 5303 | } |
bad7192b PZ |
5304 | |
5305 | active = (event->state == PERF_EVENT_STATE_ACTIVE); | |
5306 | if (active) { | |
5307 | perf_pmu_disable(ctx->pmu); | |
1e02cd40 PZ |
5308 | /* |
5309 | * We could be throttled; unthrottle now to avoid the tick | |
5310 | * trying to unthrottle while we already re-started the event. | |
5311 | */ | |
5312 | if (event->hw.interrupts == MAX_INTERRUPTS) { | |
5313 | event->hw.interrupts = 0; | |
5314 | perf_log_throttle(event, 1); | |
5315 | } | |
bad7192b PZ |
5316 | event->pmu->stop(event, PERF_EF_UPDATE); |
5317 | } | |
5318 | ||
5319 | local64_set(&event->hw.period_left, 0); | |
5320 | ||
5321 | if (active) { | |
5322 | event->pmu->start(event, PERF_EF_RELOAD); | |
5323 | perf_pmu_enable(ctx->pmu); | |
5324 | } | |
c7999c6f PZ |
5325 | } |
5326 | ||
81ec3f3c JO |
5327 | static int perf_event_check_period(struct perf_event *event, u64 value) |
5328 | { | |
5329 | return event->pmu->check_period(event, value); | |
5330 | } | |
5331 | ||
3ca270fc | 5332 | static int _perf_event_period(struct perf_event *event, u64 value) |
c7999c6f | 5333 | { |
c7999c6f PZ |
5334 | if (!is_sampling_event(event)) |
5335 | return -EINVAL; | |
5336 | ||
c7999c6f PZ |
5337 | if (!value) |
5338 | return -EINVAL; | |
5339 | ||
5340 | if (event->attr.freq && value > sysctl_perf_event_sample_rate) | |
5341 | return -EINVAL; | |
5342 | ||
81ec3f3c JO |
5343 | if (perf_event_check_period(event, value)) |
5344 | return -EINVAL; | |
5345 | ||
913a90bc RB |
5346 | if (!event->attr.freq && (value & (1ULL << 63))) |
5347 | return -EINVAL; | |
5348 | ||
fae3fde6 | 5349 | event_function_call(event, __perf_event_period, &value); |
08247e31 | 5350 | |
c7999c6f | 5351 | return 0; |
08247e31 PZ |
5352 | } |
5353 | ||
3ca270fc LX |
5354 | int perf_event_period(struct perf_event *event, u64 value) |
5355 | { | |
5356 | struct perf_event_context *ctx; | |
5357 | int ret; | |
5358 | ||
5359 | ctx = perf_event_ctx_lock(event); | |
5360 | ret = _perf_event_period(event, value); | |
5361 | perf_event_ctx_unlock(event, ctx); | |
5362 | ||
5363 | return ret; | |
5364 | } | |
5365 | EXPORT_SYMBOL_GPL(perf_event_period); | |
5366 | ||
ac9721f3 PZ |
5367 | static const struct file_operations perf_fops; |
5368 | ||
2903ff01 | 5369 | static inline int perf_fget_light(int fd, struct fd *p) |
ac9721f3 | 5370 | { |
2903ff01 AV |
5371 | struct fd f = fdget(fd); |
5372 | if (!f.file) | |
5373 | return -EBADF; | |
ac9721f3 | 5374 | |
2903ff01 AV |
5375 | if (f.file->f_op != &perf_fops) { |
5376 | fdput(f); | |
5377 | return -EBADF; | |
ac9721f3 | 5378 | } |
2903ff01 AV |
5379 | *p = f; |
5380 | return 0; | |
ac9721f3 PZ |
5381 | } |
5382 | ||
5383 | static int perf_event_set_output(struct perf_event *event, | |
5384 | struct perf_event *output_event); | |
6fb2915d | 5385 | static int perf_event_set_filter(struct perf_event *event, void __user *arg); |
2541517c | 5386 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd); |
32ff77e8 MC |
5387 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
5388 | struct perf_event_attr *attr); | |
a4be7c27 | 5389 | |
f63a8daa | 5390 | static long _perf_ioctl(struct perf_event *event, unsigned int cmd, unsigned long arg) |
d859e29f | 5391 | { |
cdd6c482 | 5392 | void (*func)(struct perf_event *); |
3df5edad | 5393 | u32 flags = arg; |
d859e29f PM |
5394 | |
5395 | switch (cmd) { | |
cdd6c482 | 5396 | case PERF_EVENT_IOC_ENABLE: |
f63a8daa | 5397 | func = _perf_event_enable; |
d859e29f | 5398 | break; |
cdd6c482 | 5399 | case PERF_EVENT_IOC_DISABLE: |
f63a8daa | 5400 | func = _perf_event_disable; |
79f14641 | 5401 | break; |
cdd6c482 | 5402 | case PERF_EVENT_IOC_RESET: |
f63a8daa | 5403 | func = _perf_event_reset; |
6de6a7b9 | 5404 | break; |
3df5edad | 5405 | |
cdd6c482 | 5406 | case PERF_EVENT_IOC_REFRESH: |
f63a8daa | 5407 | return _perf_event_refresh(event, arg); |
08247e31 | 5408 | |
cdd6c482 | 5409 | case PERF_EVENT_IOC_PERIOD: |
3ca270fc LX |
5410 | { |
5411 | u64 value; | |
08247e31 | 5412 | |
3ca270fc LX |
5413 | if (copy_from_user(&value, (u64 __user *)arg, sizeof(value))) |
5414 | return -EFAULT; | |
08247e31 | 5415 | |
3ca270fc LX |
5416 | return _perf_event_period(event, value); |
5417 | } | |
cf4957f1 JO |
5418 | case PERF_EVENT_IOC_ID: |
5419 | { | |
5420 | u64 id = primary_event_id(event); | |
5421 | ||
5422 | if (copy_to_user((void __user *)arg, &id, sizeof(id))) | |
5423 | return -EFAULT; | |
5424 | return 0; | |
5425 | } | |
5426 | ||
cdd6c482 | 5427 | case PERF_EVENT_IOC_SET_OUTPUT: |
ac9721f3 | 5428 | { |
ac9721f3 | 5429 | int ret; |
ac9721f3 | 5430 | if (arg != -1) { |
2903ff01 AV |
5431 | struct perf_event *output_event; |
5432 | struct fd output; | |
5433 | ret = perf_fget_light(arg, &output); | |
5434 | if (ret) | |
5435 | return ret; | |
5436 | output_event = output.file->private_data; | |
5437 | ret = perf_event_set_output(event, output_event); | |
5438 | fdput(output); | |
5439 | } else { | |
5440 | ret = perf_event_set_output(event, NULL); | |
ac9721f3 | 5441 | } |
ac9721f3 PZ |
5442 | return ret; |
5443 | } | |
a4be7c27 | 5444 | |
6fb2915d LZ |
5445 | case PERF_EVENT_IOC_SET_FILTER: |
5446 | return perf_event_set_filter(event, (void __user *)arg); | |
5447 | ||
2541517c AS |
5448 | case PERF_EVENT_IOC_SET_BPF: |
5449 | return perf_event_set_bpf_prog(event, arg); | |
5450 | ||
86e7972f | 5451 | case PERF_EVENT_IOC_PAUSE_OUTPUT: { |
56de4e8f | 5452 | struct perf_buffer *rb; |
86e7972f WN |
5453 | |
5454 | rcu_read_lock(); | |
5455 | rb = rcu_dereference(event->rb); | |
5456 | if (!rb || !rb->nr_pages) { | |
5457 | rcu_read_unlock(); | |
5458 | return -EINVAL; | |
5459 | } | |
5460 | rb_toggle_paused(rb, !!arg); | |
5461 | rcu_read_unlock(); | |
5462 | return 0; | |
5463 | } | |
f371b304 YS |
5464 | |
5465 | case PERF_EVENT_IOC_QUERY_BPF: | |
f4e2298e | 5466 | return perf_event_query_prog_array(event, (void __user *)arg); |
32ff77e8 MC |
5467 | |
5468 | case PERF_EVENT_IOC_MODIFY_ATTRIBUTES: { | |
5469 | struct perf_event_attr new_attr; | |
5470 | int err = perf_copy_attr((struct perf_event_attr __user *)arg, | |
5471 | &new_attr); | |
5472 | ||
5473 | if (err) | |
5474 | return err; | |
5475 | ||
5476 | return perf_event_modify_attr(event, &new_attr); | |
5477 | } | |
d859e29f | 5478 | default: |
3df5edad | 5479 | return -ENOTTY; |
d859e29f | 5480 | } |
3df5edad PZ |
5481 | |
5482 | if (flags & PERF_IOC_FLAG_GROUP) | |
cdd6c482 | 5483 | perf_event_for_each(event, func); |
3df5edad | 5484 | else |
cdd6c482 | 5485 | perf_event_for_each_child(event, func); |
3df5edad PZ |
5486 | |
5487 | return 0; | |
d859e29f PM |
5488 | } |
5489 | ||
f63a8daa PZ |
5490 | static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
5491 | { | |
5492 | struct perf_event *event = file->private_data; | |
5493 | struct perf_event_context *ctx; | |
5494 | long ret; | |
5495 | ||
da97e184 JFG |
5496 | /* Treat ioctl like writes as it is likely a mutating operation. */ |
5497 | ret = security_perf_event_write(event); | |
5498 | if (ret) | |
5499 | return ret; | |
5500 | ||
f63a8daa PZ |
5501 | ctx = perf_event_ctx_lock(event); |
5502 | ret = _perf_ioctl(event, cmd, arg); | |
5503 | perf_event_ctx_unlock(event, ctx); | |
5504 | ||
5505 | return ret; | |
5506 | } | |
5507 | ||
b3f20785 PM |
5508 | #ifdef CONFIG_COMPAT |
5509 | static long perf_compat_ioctl(struct file *file, unsigned int cmd, | |
5510 | unsigned long arg) | |
5511 | { | |
5512 | switch (_IOC_NR(cmd)) { | |
5513 | case _IOC_NR(PERF_EVENT_IOC_SET_FILTER): | |
5514 | case _IOC_NR(PERF_EVENT_IOC_ID): | |
82489c5f ES |
5515 | case _IOC_NR(PERF_EVENT_IOC_QUERY_BPF): |
5516 | case _IOC_NR(PERF_EVENT_IOC_MODIFY_ATTRIBUTES): | |
b3f20785 PM |
5517 | /* Fix up pointer size (usually 4 -> 8 in 32-on-64-bit case */ |
5518 | if (_IOC_SIZE(cmd) == sizeof(compat_uptr_t)) { | |
5519 | cmd &= ~IOCSIZE_MASK; | |
5520 | cmd |= sizeof(void *) << IOCSIZE_SHIFT; | |
5521 | } | |
5522 | break; | |
5523 | } | |
5524 | return perf_ioctl(file, cmd, arg); | |
5525 | } | |
5526 | #else | |
5527 | # define perf_compat_ioctl NULL | |
5528 | #endif | |
5529 | ||
cdd6c482 | 5530 | int perf_event_task_enable(void) |
771d7cde | 5531 | { |
f63a8daa | 5532 | struct perf_event_context *ctx; |
cdd6c482 | 5533 | struct perf_event *event; |
771d7cde | 5534 | |
cdd6c482 | 5535 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
5536 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
5537 | ctx = perf_event_ctx_lock(event); | |
5538 | perf_event_for_each_child(event, _perf_event_enable); | |
5539 | perf_event_ctx_unlock(event, ctx); | |
5540 | } | |
cdd6c482 | 5541 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
5542 | |
5543 | return 0; | |
5544 | } | |
5545 | ||
cdd6c482 | 5546 | int perf_event_task_disable(void) |
771d7cde | 5547 | { |
f63a8daa | 5548 | struct perf_event_context *ctx; |
cdd6c482 | 5549 | struct perf_event *event; |
771d7cde | 5550 | |
cdd6c482 | 5551 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
5552 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
5553 | ctx = perf_event_ctx_lock(event); | |
5554 | perf_event_for_each_child(event, _perf_event_disable); | |
5555 | perf_event_ctx_unlock(event, ctx); | |
5556 | } | |
cdd6c482 | 5557 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
5558 | |
5559 | return 0; | |
5560 | } | |
5561 | ||
cdd6c482 | 5562 | static int perf_event_index(struct perf_event *event) |
194002b2 | 5563 | { |
a4eaf7f1 PZ |
5564 | if (event->hw.state & PERF_HES_STOPPED) |
5565 | return 0; | |
5566 | ||
cdd6c482 | 5567 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
194002b2 PZ |
5568 | return 0; |
5569 | ||
35edc2a5 | 5570 | return event->pmu->event_idx(event); |
194002b2 PZ |
5571 | } |
5572 | ||
c4794295 | 5573 | static void calc_timer_values(struct perf_event *event, |
e3f3541c | 5574 | u64 *now, |
7f310a5d EM |
5575 | u64 *enabled, |
5576 | u64 *running) | |
c4794295 | 5577 | { |
e3f3541c | 5578 | u64 ctx_time; |
c4794295 | 5579 | |
e3f3541c PZ |
5580 | *now = perf_clock(); |
5581 | ctx_time = event->shadow_ctx_time + *now; | |
0d3d73aa | 5582 | __perf_update_times(event, ctx_time, enabled, running); |
c4794295 EM |
5583 | } |
5584 | ||
fa731587 PZ |
5585 | static void perf_event_init_userpage(struct perf_event *event) |
5586 | { | |
5587 | struct perf_event_mmap_page *userpg; | |
56de4e8f | 5588 | struct perf_buffer *rb; |
fa731587 PZ |
5589 | |
5590 | rcu_read_lock(); | |
5591 | rb = rcu_dereference(event->rb); | |
5592 | if (!rb) | |
5593 | goto unlock; | |
5594 | ||
5595 | userpg = rb->user_page; | |
5596 | ||
5597 | /* Allow new userspace to detect that bit 0 is deprecated */ | |
5598 | userpg->cap_bit0_is_deprecated = 1; | |
5599 | userpg->size = offsetof(struct perf_event_mmap_page, __reserved); | |
e8c6deac AS |
5600 | userpg->data_offset = PAGE_SIZE; |
5601 | userpg->data_size = perf_data_size(rb); | |
fa731587 PZ |
5602 | |
5603 | unlock: | |
5604 | rcu_read_unlock(); | |
5605 | } | |
5606 | ||
c1317ec2 AL |
5607 | void __weak arch_perf_update_userpage( |
5608 | struct perf_event *event, struct perf_event_mmap_page *userpg, u64 now) | |
e3f3541c PZ |
5609 | { |
5610 | } | |
5611 | ||
38ff667b PZ |
5612 | /* |
5613 | * Callers need to ensure there can be no nesting of this function, otherwise | |
5614 | * the seqlock logic goes bad. We can not serialize this because the arch | |
5615 | * code calls this from NMI context. | |
5616 | */ | |
cdd6c482 | 5617 | void perf_event_update_userpage(struct perf_event *event) |
37d81828 | 5618 | { |
cdd6c482 | 5619 | struct perf_event_mmap_page *userpg; |
56de4e8f | 5620 | struct perf_buffer *rb; |
e3f3541c | 5621 | u64 enabled, running, now; |
38ff667b PZ |
5622 | |
5623 | rcu_read_lock(); | |
5ec4c599 PZ |
5624 | rb = rcu_dereference(event->rb); |
5625 | if (!rb) | |
5626 | goto unlock; | |
5627 | ||
0d641208 EM |
5628 | /* |
5629 | * compute total_time_enabled, total_time_running | |
5630 | * based on snapshot values taken when the event | |
5631 | * was last scheduled in. | |
5632 | * | |
5633 | * we cannot simply called update_context_time() | |
5634 | * because of locking issue as we can be called in | |
5635 | * NMI context | |
5636 | */ | |
e3f3541c | 5637 | calc_timer_values(event, &now, &enabled, &running); |
38ff667b | 5638 | |
76369139 | 5639 | userpg = rb->user_page; |
7b732a75 | 5640 | /* |
9d2dcc8f MF |
5641 | * Disable preemption to guarantee consistent time stamps are stored to |
5642 | * the user page. | |
7b732a75 PZ |
5643 | */ |
5644 | preempt_disable(); | |
37d81828 | 5645 | ++userpg->lock; |
92f22a38 | 5646 | barrier(); |
cdd6c482 | 5647 | userpg->index = perf_event_index(event); |
b5e58793 | 5648 | userpg->offset = perf_event_count(event); |
365a4038 | 5649 | if (userpg->index) |
e7850595 | 5650 | userpg->offset -= local64_read(&event->hw.prev_count); |
7b732a75 | 5651 | |
0d641208 | 5652 | userpg->time_enabled = enabled + |
cdd6c482 | 5653 | atomic64_read(&event->child_total_time_enabled); |
7f8b4e4e | 5654 | |
0d641208 | 5655 | userpg->time_running = running + |
cdd6c482 | 5656 | atomic64_read(&event->child_total_time_running); |
7f8b4e4e | 5657 | |
c1317ec2 | 5658 | arch_perf_update_userpage(event, userpg, now); |
e3f3541c | 5659 | |
92f22a38 | 5660 | barrier(); |
37d81828 | 5661 | ++userpg->lock; |
7b732a75 | 5662 | preempt_enable(); |
38ff667b | 5663 | unlock: |
7b732a75 | 5664 | rcu_read_unlock(); |
37d81828 | 5665 | } |
82975c46 | 5666 | EXPORT_SYMBOL_GPL(perf_event_update_userpage); |
37d81828 | 5667 | |
9e3ed2d7 | 5668 | static vm_fault_t perf_mmap_fault(struct vm_fault *vmf) |
906010b2 | 5669 | { |
11bac800 | 5670 | struct perf_event *event = vmf->vma->vm_file->private_data; |
56de4e8f | 5671 | struct perf_buffer *rb; |
9e3ed2d7 | 5672 | vm_fault_t ret = VM_FAULT_SIGBUS; |
906010b2 PZ |
5673 | |
5674 | if (vmf->flags & FAULT_FLAG_MKWRITE) { | |
5675 | if (vmf->pgoff == 0) | |
5676 | ret = 0; | |
5677 | return ret; | |
5678 | } | |
5679 | ||
5680 | rcu_read_lock(); | |
76369139 FW |
5681 | rb = rcu_dereference(event->rb); |
5682 | if (!rb) | |
906010b2 PZ |
5683 | goto unlock; |
5684 | ||
5685 | if (vmf->pgoff && (vmf->flags & FAULT_FLAG_WRITE)) | |
5686 | goto unlock; | |
5687 | ||
76369139 | 5688 | vmf->page = perf_mmap_to_page(rb, vmf->pgoff); |
906010b2 PZ |
5689 | if (!vmf->page) |
5690 | goto unlock; | |
5691 | ||
5692 | get_page(vmf->page); | |
11bac800 | 5693 | vmf->page->mapping = vmf->vma->vm_file->f_mapping; |
906010b2 PZ |
5694 | vmf->page->index = vmf->pgoff; |
5695 | ||
5696 | ret = 0; | |
5697 | unlock: | |
5698 | rcu_read_unlock(); | |
5699 | ||
5700 | return ret; | |
5701 | } | |
5702 | ||
10c6db11 | 5703 | static void ring_buffer_attach(struct perf_event *event, |
56de4e8f | 5704 | struct perf_buffer *rb) |
10c6db11 | 5705 | { |
56de4e8f | 5706 | struct perf_buffer *old_rb = NULL; |
10c6db11 PZ |
5707 | unsigned long flags; |
5708 | ||
b69cf536 PZ |
5709 | if (event->rb) { |
5710 | /* | |
5711 | * Should be impossible, we set this when removing | |
5712 | * event->rb_entry and wait/clear when adding event->rb_entry. | |
5713 | */ | |
5714 | WARN_ON_ONCE(event->rcu_pending); | |
10c6db11 | 5715 | |
b69cf536 | 5716 | old_rb = event->rb; |
b69cf536 PZ |
5717 | spin_lock_irqsave(&old_rb->event_lock, flags); |
5718 | list_del_rcu(&event->rb_entry); | |
5719 | spin_unlock_irqrestore(&old_rb->event_lock, flags); | |
10c6db11 | 5720 | |
2f993cf0 ON |
5721 | event->rcu_batches = get_state_synchronize_rcu(); |
5722 | event->rcu_pending = 1; | |
b69cf536 | 5723 | } |
10c6db11 | 5724 | |
b69cf536 | 5725 | if (rb) { |
2f993cf0 ON |
5726 | if (event->rcu_pending) { |
5727 | cond_synchronize_rcu(event->rcu_batches); | |
5728 | event->rcu_pending = 0; | |
5729 | } | |
5730 | ||
b69cf536 PZ |
5731 | spin_lock_irqsave(&rb->event_lock, flags); |
5732 | list_add_rcu(&event->rb_entry, &rb->event_list); | |
5733 | spin_unlock_irqrestore(&rb->event_lock, flags); | |
5734 | } | |
5735 | ||
767ae086 AS |
5736 | /* |
5737 | * Avoid racing with perf_mmap_close(AUX): stop the event | |
5738 | * before swizzling the event::rb pointer; if it's getting | |
5739 | * unmapped, its aux_mmap_count will be 0 and it won't | |
5740 | * restart. See the comment in __perf_pmu_output_stop(). | |
5741 | * | |
5742 | * Data will inevitably be lost when set_output is done in | |
5743 | * mid-air, but then again, whoever does it like this is | |
5744 | * not in for the data anyway. | |
5745 | */ | |
5746 | if (has_aux(event)) | |
5747 | perf_event_stop(event, 0); | |
5748 | ||
b69cf536 PZ |
5749 | rcu_assign_pointer(event->rb, rb); |
5750 | ||
5751 | if (old_rb) { | |
5752 | ring_buffer_put(old_rb); | |
5753 | /* | |
5754 | * Since we detached before setting the new rb, so that we | |
5755 | * could attach the new rb, we could have missed a wakeup. | |
5756 | * Provide it now. | |
5757 | */ | |
5758 | wake_up_all(&event->waitq); | |
5759 | } | |
10c6db11 PZ |
5760 | } |
5761 | ||
5762 | static void ring_buffer_wakeup(struct perf_event *event) | |
5763 | { | |
56de4e8f | 5764 | struct perf_buffer *rb; |
10c6db11 PZ |
5765 | |
5766 | rcu_read_lock(); | |
5767 | rb = rcu_dereference(event->rb); | |
9bb5d40c PZ |
5768 | if (rb) { |
5769 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) | |
5770 | wake_up_all(&event->waitq); | |
5771 | } | |
10c6db11 PZ |
5772 | rcu_read_unlock(); |
5773 | } | |
5774 | ||
56de4e8f | 5775 | struct perf_buffer *ring_buffer_get(struct perf_event *event) |
7b732a75 | 5776 | { |
56de4e8f | 5777 | struct perf_buffer *rb; |
7b732a75 | 5778 | |
ac9721f3 | 5779 | rcu_read_lock(); |
76369139 FW |
5780 | rb = rcu_dereference(event->rb); |
5781 | if (rb) { | |
fecb8ed2 | 5782 | if (!refcount_inc_not_zero(&rb->refcount)) |
76369139 | 5783 | rb = NULL; |
ac9721f3 PZ |
5784 | } |
5785 | rcu_read_unlock(); | |
5786 | ||
76369139 | 5787 | return rb; |
ac9721f3 PZ |
5788 | } |
5789 | ||
56de4e8f | 5790 | void ring_buffer_put(struct perf_buffer *rb) |
ac9721f3 | 5791 | { |
fecb8ed2 | 5792 | if (!refcount_dec_and_test(&rb->refcount)) |
ac9721f3 | 5793 | return; |
7b732a75 | 5794 | |
9bb5d40c | 5795 | WARN_ON_ONCE(!list_empty(&rb->event_list)); |
10c6db11 | 5796 | |
76369139 | 5797 | call_rcu(&rb->rcu_head, rb_free_rcu); |
7b732a75 PZ |
5798 | } |
5799 | ||
5800 | static void perf_mmap_open(struct vm_area_struct *vma) | |
5801 | { | |
cdd6c482 | 5802 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 5803 | |
cdd6c482 | 5804 | atomic_inc(&event->mmap_count); |
9bb5d40c | 5805 | atomic_inc(&event->rb->mmap_count); |
1e0fb9ec | 5806 | |
45bfb2e5 PZ |
5807 | if (vma->vm_pgoff) |
5808 | atomic_inc(&event->rb->aux_mmap_count); | |
5809 | ||
1e0fb9ec | 5810 | if (event->pmu->event_mapped) |
bfe33492 | 5811 | event->pmu->event_mapped(event, vma->vm_mm); |
7b732a75 PZ |
5812 | } |
5813 | ||
95ff4ca2 AS |
5814 | static void perf_pmu_output_stop(struct perf_event *event); |
5815 | ||
9bb5d40c PZ |
5816 | /* |
5817 | * A buffer can be mmap()ed multiple times; either directly through the same | |
5818 | * event, or through other events by use of perf_event_set_output(). | |
5819 | * | |
5820 | * In order to undo the VM accounting done by perf_mmap() we need to destroy | |
5821 | * the buffer here, where we still have a VM context. This means we need | |
5822 | * to detach all events redirecting to us. | |
5823 | */ | |
7b732a75 PZ |
5824 | static void perf_mmap_close(struct vm_area_struct *vma) |
5825 | { | |
cdd6c482 | 5826 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 5827 | |
56de4e8f | 5828 | struct perf_buffer *rb = ring_buffer_get(event); |
9bb5d40c PZ |
5829 | struct user_struct *mmap_user = rb->mmap_user; |
5830 | int mmap_locked = rb->mmap_locked; | |
5831 | unsigned long size = perf_data_size(rb); | |
789f90fc | 5832 | |
1e0fb9ec | 5833 | if (event->pmu->event_unmapped) |
bfe33492 | 5834 | event->pmu->event_unmapped(event, vma->vm_mm); |
1e0fb9ec | 5835 | |
45bfb2e5 PZ |
5836 | /* |
5837 | * rb->aux_mmap_count will always drop before rb->mmap_count and | |
5838 | * event->mmap_count, so it is ok to use event->mmap_mutex to | |
5839 | * serialize with perf_mmap here. | |
5840 | */ | |
5841 | if (rb_has_aux(rb) && vma->vm_pgoff == rb->aux_pgoff && | |
5842 | atomic_dec_and_mutex_lock(&rb->aux_mmap_count, &event->mmap_mutex)) { | |
95ff4ca2 AS |
5843 | /* |
5844 | * Stop all AUX events that are writing to this buffer, | |
5845 | * so that we can free its AUX pages and corresponding PMU | |
5846 | * data. Note that after rb::aux_mmap_count dropped to zero, | |
5847 | * they won't start any more (see perf_aux_output_begin()). | |
5848 | */ | |
5849 | perf_pmu_output_stop(event); | |
5850 | ||
5851 | /* now it's safe to free the pages */ | |
36b3db03 AS |
5852 | atomic_long_sub(rb->aux_nr_pages - rb->aux_mmap_locked, &mmap_user->locked_vm); |
5853 | atomic64_sub(rb->aux_mmap_locked, &vma->vm_mm->pinned_vm); | |
45bfb2e5 | 5854 | |
95ff4ca2 | 5855 | /* this has to be the last one */ |
45bfb2e5 | 5856 | rb_free_aux(rb); |
ca3bb3d0 | 5857 | WARN_ON_ONCE(refcount_read(&rb->aux_refcount)); |
95ff4ca2 | 5858 | |
45bfb2e5 PZ |
5859 | mutex_unlock(&event->mmap_mutex); |
5860 | } | |
5861 | ||
9bb5d40c PZ |
5862 | atomic_dec(&rb->mmap_count); |
5863 | ||
5864 | if (!atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex)) | |
b69cf536 | 5865 | goto out_put; |
9bb5d40c | 5866 | |
b69cf536 | 5867 | ring_buffer_attach(event, NULL); |
9bb5d40c PZ |
5868 | mutex_unlock(&event->mmap_mutex); |
5869 | ||
5870 | /* If there's still other mmap()s of this buffer, we're done. */ | |
b69cf536 PZ |
5871 | if (atomic_read(&rb->mmap_count)) |
5872 | goto out_put; | |
ac9721f3 | 5873 | |
9bb5d40c PZ |
5874 | /* |
5875 | * No other mmap()s, detach from all other events that might redirect | |
5876 | * into the now unreachable buffer. Somewhat complicated by the | |
5877 | * fact that rb::event_lock otherwise nests inside mmap_mutex. | |
5878 | */ | |
5879 | again: | |
5880 | rcu_read_lock(); | |
5881 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) { | |
5882 | if (!atomic_long_inc_not_zero(&event->refcount)) { | |
5883 | /* | |
5884 | * This event is en-route to free_event() which will | |
5885 | * detach it and remove it from the list. | |
5886 | */ | |
5887 | continue; | |
5888 | } | |
5889 | rcu_read_unlock(); | |
789f90fc | 5890 | |
9bb5d40c PZ |
5891 | mutex_lock(&event->mmap_mutex); |
5892 | /* | |
5893 | * Check we didn't race with perf_event_set_output() which can | |
5894 | * swizzle the rb from under us while we were waiting to | |
5895 | * acquire mmap_mutex. | |
5896 | * | |
5897 | * If we find a different rb; ignore this event, a next | |
5898 | * iteration will no longer find it on the list. We have to | |
5899 | * still restart the iteration to make sure we're not now | |
5900 | * iterating the wrong list. | |
5901 | */ | |
b69cf536 PZ |
5902 | if (event->rb == rb) |
5903 | ring_buffer_attach(event, NULL); | |
5904 | ||
cdd6c482 | 5905 | mutex_unlock(&event->mmap_mutex); |
9bb5d40c | 5906 | put_event(event); |
ac9721f3 | 5907 | |
9bb5d40c PZ |
5908 | /* |
5909 | * Restart the iteration; either we're on the wrong list or | |
5910 | * destroyed its integrity by doing a deletion. | |
5911 | */ | |
5912 | goto again; | |
7b732a75 | 5913 | } |
9bb5d40c PZ |
5914 | rcu_read_unlock(); |
5915 | ||
5916 | /* | |
5917 | * It could be there's still a few 0-ref events on the list; they'll | |
5918 | * get cleaned up by free_event() -- they'll also still have their | |
5919 | * ref on the rb and will free it whenever they are done with it. | |
5920 | * | |
5921 | * Aside from that, this buffer is 'fully' detached and unmapped, | |
5922 | * undo the VM accounting. | |
5923 | */ | |
5924 | ||
d44248a4 SL |
5925 | atomic_long_sub((size >> PAGE_SHIFT) + 1 - mmap_locked, |
5926 | &mmap_user->locked_vm); | |
70f8a3ca | 5927 | atomic64_sub(mmap_locked, &vma->vm_mm->pinned_vm); |
9bb5d40c PZ |
5928 | free_uid(mmap_user); |
5929 | ||
b69cf536 | 5930 | out_put: |
9bb5d40c | 5931 | ring_buffer_put(rb); /* could be last */ |
37d81828 PM |
5932 | } |
5933 | ||
f0f37e2f | 5934 | static const struct vm_operations_struct perf_mmap_vmops = { |
43a21ea8 | 5935 | .open = perf_mmap_open, |
fca0c116 | 5936 | .close = perf_mmap_close, /* non mergeable */ |
43a21ea8 PZ |
5937 | .fault = perf_mmap_fault, |
5938 | .page_mkwrite = perf_mmap_fault, | |
37d81828 PM |
5939 | }; |
5940 | ||
5941 | static int perf_mmap(struct file *file, struct vm_area_struct *vma) | |
5942 | { | |
cdd6c482 | 5943 | struct perf_event *event = file->private_data; |
22a4f650 | 5944 | unsigned long user_locked, user_lock_limit; |
789f90fc | 5945 | struct user_struct *user = current_user(); |
56de4e8f | 5946 | struct perf_buffer *rb = NULL; |
22a4f650 | 5947 | unsigned long locked, lock_limit; |
7b732a75 PZ |
5948 | unsigned long vma_size; |
5949 | unsigned long nr_pages; | |
45bfb2e5 | 5950 | long user_extra = 0, extra = 0; |
d57e34fd | 5951 | int ret = 0, flags = 0; |
37d81828 | 5952 | |
c7920614 PZ |
5953 | /* |
5954 | * Don't allow mmap() of inherited per-task counters. This would | |
5955 | * create a performance issue due to all children writing to the | |
76369139 | 5956 | * same rb. |
c7920614 PZ |
5957 | */ |
5958 | if (event->cpu == -1 && event->attr.inherit) | |
5959 | return -EINVAL; | |
5960 | ||
43a21ea8 | 5961 | if (!(vma->vm_flags & VM_SHARED)) |
37d81828 | 5962 | return -EINVAL; |
7b732a75 | 5963 | |
da97e184 JFG |
5964 | ret = security_perf_event_read(event); |
5965 | if (ret) | |
5966 | return ret; | |
5967 | ||
7b732a75 | 5968 | vma_size = vma->vm_end - vma->vm_start; |
45bfb2e5 PZ |
5969 | |
5970 | if (vma->vm_pgoff == 0) { | |
5971 | nr_pages = (vma_size / PAGE_SIZE) - 1; | |
5972 | } else { | |
5973 | /* | |
5974 | * AUX area mapping: if rb->aux_nr_pages != 0, it's already | |
5975 | * mapped, all subsequent mappings should have the same size | |
5976 | * and offset. Must be above the normal perf buffer. | |
5977 | */ | |
5978 | u64 aux_offset, aux_size; | |
5979 | ||
5980 | if (!event->rb) | |
5981 | return -EINVAL; | |
5982 | ||
5983 | nr_pages = vma_size / PAGE_SIZE; | |
5984 | ||
5985 | mutex_lock(&event->mmap_mutex); | |
5986 | ret = -EINVAL; | |
5987 | ||
5988 | rb = event->rb; | |
5989 | if (!rb) | |
5990 | goto aux_unlock; | |
5991 | ||
6aa7de05 MR |
5992 | aux_offset = READ_ONCE(rb->user_page->aux_offset); |
5993 | aux_size = READ_ONCE(rb->user_page->aux_size); | |
45bfb2e5 PZ |
5994 | |
5995 | if (aux_offset < perf_data_size(rb) + PAGE_SIZE) | |
5996 | goto aux_unlock; | |
5997 | ||
5998 | if (aux_offset != vma->vm_pgoff << PAGE_SHIFT) | |
5999 | goto aux_unlock; | |
6000 | ||
6001 | /* already mapped with a different offset */ | |
6002 | if (rb_has_aux(rb) && rb->aux_pgoff != vma->vm_pgoff) | |
6003 | goto aux_unlock; | |
6004 | ||
6005 | if (aux_size != vma_size || aux_size != nr_pages * PAGE_SIZE) | |
6006 | goto aux_unlock; | |
6007 | ||
6008 | /* already mapped with a different size */ | |
6009 | if (rb_has_aux(rb) && rb->aux_nr_pages != nr_pages) | |
6010 | goto aux_unlock; | |
6011 | ||
6012 | if (!is_power_of_2(nr_pages)) | |
6013 | goto aux_unlock; | |
6014 | ||
6015 | if (!atomic_inc_not_zero(&rb->mmap_count)) | |
6016 | goto aux_unlock; | |
6017 | ||
6018 | if (rb_has_aux(rb)) { | |
6019 | atomic_inc(&rb->aux_mmap_count); | |
6020 | ret = 0; | |
6021 | goto unlock; | |
6022 | } | |
6023 | ||
6024 | atomic_set(&rb->aux_mmap_count, 1); | |
6025 | user_extra = nr_pages; | |
6026 | ||
6027 | goto accounting; | |
6028 | } | |
7b732a75 | 6029 | |
7730d865 | 6030 | /* |
76369139 | 6031 | * If we have rb pages ensure they're a power-of-two number, so we |
7730d865 PZ |
6032 | * can do bitmasks instead of modulo. |
6033 | */ | |
2ed11312 | 6034 | if (nr_pages != 0 && !is_power_of_2(nr_pages)) |
37d81828 PM |
6035 | return -EINVAL; |
6036 | ||
7b732a75 | 6037 | if (vma_size != PAGE_SIZE * (1 + nr_pages)) |
37d81828 PM |
6038 | return -EINVAL; |
6039 | ||
cdd6c482 | 6040 | WARN_ON_ONCE(event->ctx->parent_ctx); |
9bb5d40c | 6041 | again: |
cdd6c482 | 6042 | mutex_lock(&event->mmap_mutex); |
76369139 | 6043 | if (event->rb) { |
9bb5d40c | 6044 | if (event->rb->nr_pages != nr_pages) { |
ebb3c4c4 | 6045 | ret = -EINVAL; |
9bb5d40c PZ |
6046 | goto unlock; |
6047 | } | |
6048 | ||
6049 | if (!atomic_inc_not_zero(&event->rb->mmap_count)) { | |
6050 | /* | |
6051 | * Raced against perf_mmap_close() through | |
6052 | * perf_event_set_output(). Try again, hope for better | |
6053 | * luck. | |
6054 | */ | |
6055 | mutex_unlock(&event->mmap_mutex); | |
6056 | goto again; | |
6057 | } | |
6058 | ||
ebb3c4c4 PZ |
6059 | goto unlock; |
6060 | } | |
6061 | ||
789f90fc | 6062 | user_extra = nr_pages + 1; |
45bfb2e5 PZ |
6063 | |
6064 | accounting: | |
cdd6c482 | 6065 | user_lock_limit = sysctl_perf_event_mlock >> (PAGE_SHIFT - 10); |
a3862d3f IM |
6066 | |
6067 | /* | |
6068 | * Increase the limit linearly with more CPUs: | |
6069 | */ | |
6070 | user_lock_limit *= num_online_cpus(); | |
6071 | ||
00346155 SL |
6072 | user_locked = atomic_long_read(&user->locked_vm); |
6073 | ||
6074 | /* | |
6075 | * sysctl_perf_event_mlock may have changed, so that | |
6076 | * user->locked_vm > user_lock_limit | |
6077 | */ | |
6078 | if (user_locked > user_lock_limit) | |
6079 | user_locked = user_lock_limit; | |
6080 | user_locked += user_extra; | |
c5078f78 | 6081 | |
c4b75479 | 6082 | if (user_locked > user_lock_limit) { |
d44248a4 SL |
6083 | /* |
6084 | * charge locked_vm until it hits user_lock_limit; | |
6085 | * charge the rest from pinned_vm | |
6086 | */ | |
789f90fc | 6087 | extra = user_locked - user_lock_limit; |
d44248a4 SL |
6088 | user_extra -= extra; |
6089 | } | |
7b732a75 | 6090 | |
78d7d407 | 6091 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
7b732a75 | 6092 | lock_limit >>= PAGE_SHIFT; |
70f8a3ca | 6093 | locked = atomic64_read(&vma->vm_mm->pinned_vm) + extra; |
7b732a75 | 6094 | |
da97e184 | 6095 | if ((locked > lock_limit) && perf_is_paranoid() && |
459ec28a | 6096 | !capable(CAP_IPC_LOCK)) { |
ebb3c4c4 PZ |
6097 | ret = -EPERM; |
6098 | goto unlock; | |
6099 | } | |
7b732a75 | 6100 | |
45bfb2e5 | 6101 | WARN_ON(!rb && event->rb); |
906010b2 | 6102 | |
d57e34fd | 6103 | if (vma->vm_flags & VM_WRITE) |
76369139 | 6104 | flags |= RING_BUFFER_WRITABLE; |
d57e34fd | 6105 | |
76369139 | 6106 | if (!rb) { |
45bfb2e5 PZ |
6107 | rb = rb_alloc(nr_pages, |
6108 | event->attr.watermark ? event->attr.wakeup_watermark : 0, | |
6109 | event->cpu, flags); | |
26cb63ad | 6110 | |
45bfb2e5 PZ |
6111 | if (!rb) { |
6112 | ret = -ENOMEM; | |
6113 | goto unlock; | |
6114 | } | |
43a21ea8 | 6115 | |
45bfb2e5 PZ |
6116 | atomic_set(&rb->mmap_count, 1); |
6117 | rb->mmap_user = get_current_user(); | |
6118 | rb->mmap_locked = extra; | |
26cb63ad | 6119 | |
45bfb2e5 | 6120 | ring_buffer_attach(event, rb); |
ac9721f3 | 6121 | |
45bfb2e5 PZ |
6122 | perf_event_init_userpage(event); |
6123 | perf_event_update_userpage(event); | |
6124 | } else { | |
1a594131 AS |
6125 | ret = rb_alloc_aux(rb, event, vma->vm_pgoff, nr_pages, |
6126 | event->attr.aux_watermark, flags); | |
45bfb2e5 PZ |
6127 | if (!ret) |
6128 | rb->aux_mmap_locked = extra; | |
6129 | } | |
9a0f05cb | 6130 | |
ebb3c4c4 | 6131 | unlock: |
45bfb2e5 PZ |
6132 | if (!ret) { |
6133 | atomic_long_add(user_extra, &user->locked_vm); | |
70f8a3ca | 6134 | atomic64_add(extra, &vma->vm_mm->pinned_vm); |
45bfb2e5 | 6135 | |
ac9721f3 | 6136 | atomic_inc(&event->mmap_count); |
45bfb2e5 PZ |
6137 | } else if (rb) { |
6138 | atomic_dec(&rb->mmap_count); | |
6139 | } | |
6140 | aux_unlock: | |
cdd6c482 | 6141 | mutex_unlock(&event->mmap_mutex); |
37d81828 | 6142 | |
9bb5d40c PZ |
6143 | /* |
6144 | * Since pinned accounting is per vm we cannot allow fork() to copy our | |
6145 | * vma. | |
6146 | */ | |
26cb63ad | 6147 | vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND | VM_DONTDUMP; |
37d81828 | 6148 | vma->vm_ops = &perf_mmap_vmops; |
7b732a75 | 6149 | |
1e0fb9ec | 6150 | if (event->pmu->event_mapped) |
bfe33492 | 6151 | event->pmu->event_mapped(event, vma->vm_mm); |
1e0fb9ec | 6152 | |
7b732a75 | 6153 | return ret; |
37d81828 PM |
6154 | } |
6155 | ||
3c446b3d PZ |
6156 | static int perf_fasync(int fd, struct file *filp, int on) |
6157 | { | |
496ad9aa | 6158 | struct inode *inode = file_inode(filp); |
cdd6c482 | 6159 | struct perf_event *event = filp->private_data; |
3c446b3d PZ |
6160 | int retval; |
6161 | ||
5955102c | 6162 | inode_lock(inode); |
cdd6c482 | 6163 | retval = fasync_helper(fd, filp, on, &event->fasync); |
5955102c | 6164 | inode_unlock(inode); |
3c446b3d PZ |
6165 | |
6166 | if (retval < 0) | |
6167 | return retval; | |
6168 | ||
6169 | return 0; | |
6170 | } | |
6171 | ||
0793a61d | 6172 | static const struct file_operations perf_fops = { |
3326c1ce | 6173 | .llseek = no_llseek, |
0793a61d TG |
6174 | .release = perf_release, |
6175 | .read = perf_read, | |
6176 | .poll = perf_poll, | |
d859e29f | 6177 | .unlocked_ioctl = perf_ioctl, |
b3f20785 | 6178 | .compat_ioctl = perf_compat_ioctl, |
37d81828 | 6179 | .mmap = perf_mmap, |
3c446b3d | 6180 | .fasync = perf_fasync, |
0793a61d TG |
6181 | }; |
6182 | ||
925d519a | 6183 | /* |
cdd6c482 | 6184 | * Perf event wakeup |
925d519a PZ |
6185 | * |
6186 | * If there's data, ensure we set the poll() state and publish everything | |
6187 | * to user-space before waking everybody up. | |
6188 | */ | |
6189 | ||
fed66e2c PZ |
6190 | static inline struct fasync_struct **perf_event_fasync(struct perf_event *event) |
6191 | { | |
6192 | /* only the parent has fasync state */ | |
6193 | if (event->parent) | |
6194 | event = event->parent; | |
6195 | return &event->fasync; | |
6196 | } | |
6197 | ||
cdd6c482 | 6198 | void perf_event_wakeup(struct perf_event *event) |
925d519a | 6199 | { |
10c6db11 | 6200 | ring_buffer_wakeup(event); |
4c9e2542 | 6201 | |
cdd6c482 | 6202 | if (event->pending_kill) { |
fed66e2c | 6203 | kill_fasync(perf_event_fasync(event), SIGIO, event->pending_kill); |
cdd6c482 | 6204 | event->pending_kill = 0; |
4c9e2542 | 6205 | } |
925d519a PZ |
6206 | } |
6207 | ||
1d54ad94 PZ |
6208 | static void perf_pending_event_disable(struct perf_event *event) |
6209 | { | |
6210 | int cpu = READ_ONCE(event->pending_disable); | |
6211 | ||
6212 | if (cpu < 0) | |
6213 | return; | |
6214 | ||
6215 | if (cpu == smp_processor_id()) { | |
6216 | WRITE_ONCE(event->pending_disable, -1); | |
6217 | perf_event_disable_local(event); | |
6218 | return; | |
6219 | } | |
6220 | ||
6221 | /* | |
6222 | * CPU-A CPU-B | |
6223 | * | |
6224 | * perf_event_disable_inatomic() | |
6225 | * @pending_disable = CPU-A; | |
6226 | * irq_work_queue(); | |
6227 | * | |
6228 | * sched-out | |
6229 | * @pending_disable = -1; | |
6230 | * | |
6231 | * sched-in | |
6232 | * perf_event_disable_inatomic() | |
6233 | * @pending_disable = CPU-B; | |
6234 | * irq_work_queue(); // FAILS | |
6235 | * | |
6236 | * irq_work_run() | |
6237 | * perf_pending_event() | |
6238 | * | |
6239 | * But the event runs on CPU-B and wants disabling there. | |
6240 | */ | |
6241 | irq_work_queue_on(&event->pending, cpu); | |
6242 | } | |
6243 | ||
e360adbe | 6244 | static void perf_pending_event(struct irq_work *entry) |
79f14641 | 6245 | { |
1d54ad94 | 6246 | struct perf_event *event = container_of(entry, struct perf_event, pending); |
d525211f PZ |
6247 | int rctx; |
6248 | ||
6249 | rctx = perf_swevent_get_recursion_context(); | |
6250 | /* | |
6251 | * If we 'fail' here, that's OK, it means recursion is already disabled | |
6252 | * and we won't recurse 'further'. | |
6253 | */ | |
79f14641 | 6254 | |
1d54ad94 | 6255 | perf_pending_event_disable(event); |
79f14641 | 6256 | |
cdd6c482 IM |
6257 | if (event->pending_wakeup) { |
6258 | event->pending_wakeup = 0; | |
6259 | perf_event_wakeup(event); | |
79f14641 | 6260 | } |
d525211f PZ |
6261 | |
6262 | if (rctx >= 0) | |
6263 | perf_swevent_put_recursion_context(rctx); | |
79f14641 PZ |
6264 | } |
6265 | ||
39447b38 ZY |
6266 | /* |
6267 | * We assume there is only KVM supporting the callbacks. | |
6268 | * Later on, we might change it to a list if there is | |
6269 | * another virtualization implementation supporting the callbacks. | |
6270 | */ | |
6271 | struct perf_guest_info_callbacks *perf_guest_cbs; | |
6272 | ||
6273 | int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
6274 | { | |
6275 | perf_guest_cbs = cbs; | |
6276 | return 0; | |
6277 | } | |
6278 | EXPORT_SYMBOL_GPL(perf_register_guest_info_callbacks); | |
6279 | ||
6280 | int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
6281 | { | |
6282 | perf_guest_cbs = NULL; | |
6283 | return 0; | |
6284 | } | |
6285 | EXPORT_SYMBOL_GPL(perf_unregister_guest_info_callbacks); | |
6286 | ||
4018994f JO |
6287 | static void |
6288 | perf_output_sample_regs(struct perf_output_handle *handle, | |
6289 | struct pt_regs *regs, u64 mask) | |
6290 | { | |
6291 | int bit; | |
29dd3288 | 6292 | DECLARE_BITMAP(_mask, 64); |
4018994f | 6293 | |
29dd3288 MS |
6294 | bitmap_from_u64(_mask, mask); |
6295 | for_each_set_bit(bit, _mask, sizeof(mask) * BITS_PER_BYTE) { | |
4018994f JO |
6296 | u64 val; |
6297 | ||
6298 | val = perf_reg_value(regs, bit); | |
6299 | perf_output_put(handle, val); | |
6300 | } | |
6301 | } | |
6302 | ||
60e2364e | 6303 | static void perf_sample_regs_user(struct perf_regs *regs_user, |
88a7c26a AL |
6304 | struct pt_regs *regs, |
6305 | struct pt_regs *regs_user_copy) | |
4018994f | 6306 | { |
88a7c26a AL |
6307 | if (user_mode(regs)) { |
6308 | regs_user->abi = perf_reg_abi(current); | |
2565711f | 6309 | regs_user->regs = regs; |
085ebfe9 | 6310 | } else if (!(current->flags & PF_KTHREAD)) { |
88a7c26a | 6311 | perf_get_regs_user(regs_user, regs, regs_user_copy); |
2565711f PZ |
6312 | } else { |
6313 | regs_user->abi = PERF_SAMPLE_REGS_ABI_NONE; | |
6314 | regs_user->regs = NULL; | |
4018994f JO |
6315 | } |
6316 | } | |
6317 | ||
60e2364e SE |
6318 | static void perf_sample_regs_intr(struct perf_regs *regs_intr, |
6319 | struct pt_regs *regs) | |
6320 | { | |
6321 | regs_intr->regs = regs; | |
6322 | regs_intr->abi = perf_reg_abi(current); | |
6323 | } | |
6324 | ||
6325 | ||
c5ebcedb JO |
6326 | /* |
6327 | * Get remaining task size from user stack pointer. | |
6328 | * | |
6329 | * It'd be better to take stack vma map and limit this more | |
9f014e3a | 6330 | * precisely, but there's no way to get it safely under interrupt, |
c5ebcedb JO |
6331 | * so using TASK_SIZE as limit. |
6332 | */ | |
6333 | static u64 perf_ustack_task_size(struct pt_regs *regs) | |
6334 | { | |
6335 | unsigned long addr = perf_user_stack_pointer(regs); | |
6336 | ||
6337 | if (!addr || addr >= TASK_SIZE) | |
6338 | return 0; | |
6339 | ||
6340 | return TASK_SIZE - addr; | |
6341 | } | |
6342 | ||
6343 | static u16 | |
6344 | perf_sample_ustack_size(u16 stack_size, u16 header_size, | |
6345 | struct pt_regs *regs) | |
6346 | { | |
6347 | u64 task_size; | |
6348 | ||
6349 | /* No regs, no stack pointer, no dump. */ | |
6350 | if (!regs) | |
6351 | return 0; | |
6352 | ||
6353 | /* | |
6354 | * Check if we fit in with the requested stack size into the: | |
6355 | * - TASK_SIZE | |
6356 | * If we don't, we limit the size to the TASK_SIZE. | |
6357 | * | |
6358 | * - remaining sample size | |
6359 | * If we don't, we customize the stack size to | |
6360 | * fit in to the remaining sample size. | |
6361 | */ | |
6362 | ||
6363 | task_size = min((u64) USHRT_MAX, perf_ustack_task_size(regs)); | |
6364 | stack_size = min(stack_size, (u16) task_size); | |
6365 | ||
6366 | /* Current header size plus static size and dynamic size. */ | |
6367 | header_size += 2 * sizeof(u64); | |
6368 | ||
6369 | /* Do we fit in with the current stack dump size? */ | |
6370 | if ((u16) (header_size + stack_size) < header_size) { | |
6371 | /* | |
6372 | * If we overflow the maximum size for the sample, | |
6373 | * we customize the stack dump size to fit in. | |
6374 | */ | |
6375 | stack_size = USHRT_MAX - header_size - sizeof(u64); | |
6376 | stack_size = round_up(stack_size, sizeof(u64)); | |
6377 | } | |
6378 | ||
6379 | return stack_size; | |
6380 | } | |
6381 | ||
6382 | static void | |
6383 | perf_output_sample_ustack(struct perf_output_handle *handle, u64 dump_size, | |
6384 | struct pt_regs *regs) | |
6385 | { | |
6386 | /* Case of a kernel thread, nothing to dump */ | |
6387 | if (!regs) { | |
6388 | u64 size = 0; | |
6389 | perf_output_put(handle, size); | |
6390 | } else { | |
6391 | unsigned long sp; | |
6392 | unsigned int rem; | |
6393 | u64 dyn_size; | |
02e18447 | 6394 | mm_segment_t fs; |
c5ebcedb JO |
6395 | |
6396 | /* | |
6397 | * We dump: | |
6398 | * static size | |
6399 | * - the size requested by user or the best one we can fit | |
6400 | * in to the sample max size | |
6401 | * data | |
6402 | * - user stack dump data | |
6403 | * dynamic size | |
6404 | * - the actual dumped size | |
6405 | */ | |
6406 | ||
6407 | /* Static size. */ | |
6408 | perf_output_put(handle, dump_size); | |
6409 | ||
6410 | /* Data. */ | |
6411 | sp = perf_user_stack_pointer(regs); | |
02e18447 YC |
6412 | fs = get_fs(); |
6413 | set_fs(USER_DS); | |
c5ebcedb | 6414 | rem = __output_copy_user(handle, (void *) sp, dump_size); |
02e18447 | 6415 | set_fs(fs); |
c5ebcedb JO |
6416 | dyn_size = dump_size - rem; |
6417 | ||
6418 | perf_output_skip(handle, rem); | |
6419 | ||
6420 | /* Dynamic size. */ | |
6421 | perf_output_put(handle, dyn_size); | |
6422 | } | |
6423 | } | |
6424 | ||
a4faf00d AS |
6425 | static unsigned long perf_prepare_sample_aux(struct perf_event *event, |
6426 | struct perf_sample_data *data, | |
6427 | size_t size) | |
6428 | { | |
6429 | struct perf_event *sampler = event->aux_event; | |
56de4e8f | 6430 | struct perf_buffer *rb; |
a4faf00d AS |
6431 | |
6432 | data->aux_size = 0; | |
6433 | ||
6434 | if (!sampler) | |
6435 | goto out; | |
6436 | ||
6437 | if (WARN_ON_ONCE(READ_ONCE(sampler->state) != PERF_EVENT_STATE_ACTIVE)) | |
6438 | goto out; | |
6439 | ||
6440 | if (WARN_ON_ONCE(READ_ONCE(sampler->oncpu) != smp_processor_id())) | |
6441 | goto out; | |
6442 | ||
6443 | rb = ring_buffer_get(sampler->parent ? sampler->parent : sampler); | |
6444 | if (!rb) | |
6445 | goto out; | |
6446 | ||
6447 | /* | |
6448 | * If this is an NMI hit inside sampling code, don't take | |
6449 | * the sample. See also perf_aux_sample_output(). | |
6450 | */ | |
6451 | if (READ_ONCE(rb->aux_in_sampling)) { | |
6452 | data->aux_size = 0; | |
6453 | } else { | |
6454 | size = min_t(size_t, size, perf_aux_size(rb)); | |
6455 | data->aux_size = ALIGN(size, sizeof(u64)); | |
6456 | } | |
6457 | ring_buffer_put(rb); | |
6458 | ||
6459 | out: | |
6460 | return data->aux_size; | |
6461 | } | |
6462 | ||
56de4e8f | 6463 | long perf_pmu_snapshot_aux(struct perf_buffer *rb, |
a4faf00d AS |
6464 | struct perf_event *event, |
6465 | struct perf_output_handle *handle, | |
6466 | unsigned long size) | |
6467 | { | |
6468 | unsigned long flags; | |
6469 | long ret; | |
6470 | ||
6471 | /* | |
6472 | * Normal ->start()/->stop() callbacks run in IRQ mode in scheduler | |
6473 | * paths. If we start calling them in NMI context, they may race with | |
6474 | * the IRQ ones, that is, for example, re-starting an event that's just | |
6475 | * been stopped, which is why we're using a separate callback that | |
6476 | * doesn't change the event state. | |
6477 | * | |
6478 | * IRQs need to be disabled to prevent IPIs from racing with us. | |
6479 | */ | |
6480 | local_irq_save(flags); | |
6481 | /* | |
6482 | * Guard against NMI hits inside the critical section; | |
6483 | * see also perf_prepare_sample_aux(). | |
6484 | */ | |
6485 | WRITE_ONCE(rb->aux_in_sampling, 1); | |
6486 | barrier(); | |
6487 | ||
6488 | ret = event->pmu->snapshot_aux(event, handle, size); | |
6489 | ||
6490 | barrier(); | |
6491 | WRITE_ONCE(rb->aux_in_sampling, 0); | |
6492 | local_irq_restore(flags); | |
6493 | ||
6494 | return ret; | |
6495 | } | |
6496 | ||
6497 | static void perf_aux_sample_output(struct perf_event *event, | |
6498 | struct perf_output_handle *handle, | |
6499 | struct perf_sample_data *data) | |
6500 | { | |
6501 | struct perf_event *sampler = event->aux_event; | |
56de4e8f | 6502 | struct perf_buffer *rb; |
a4faf00d | 6503 | unsigned long pad; |
a4faf00d AS |
6504 | long size; |
6505 | ||
6506 | if (WARN_ON_ONCE(!sampler || !data->aux_size)) | |
6507 | return; | |
6508 | ||
6509 | rb = ring_buffer_get(sampler->parent ? sampler->parent : sampler); | |
6510 | if (!rb) | |
6511 | return; | |
6512 | ||
6513 | size = perf_pmu_snapshot_aux(rb, sampler, handle, data->aux_size); | |
6514 | ||
6515 | /* | |
6516 | * An error here means that perf_output_copy() failed (returned a | |
6517 | * non-zero surplus that it didn't copy), which in its current | |
6518 | * enlightened implementation is not possible. If that changes, we'd | |
6519 | * like to know. | |
6520 | */ | |
6521 | if (WARN_ON_ONCE(size < 0)) | |
6522 | goto out_put; | |
6523 | ||
6524 | /* | |
6525 | * The pad comes from ALIGN()ing data->aux_size up to u64 in | |
6526 | * perf_prepare_sample_aux(), so should not be more than that. | |
6527 | */ | |
6528 | pad = data->aux_size - size; | |
6529 | if (WARN_ON_ONCE(pad >= sizeof(u64))) | |
6530 | pad = 8; | |
6531 | ||
6532 | if (pad) { | |
6533 | u64 zero = 0; | |
6534 | perf_output_copy(handle, &zero, pad); | |
6535 | } | |
6536 | ||
6537 | out_put: | |
6538 | ring_buffer_put(rb); | |
6539 | } | |
6540 | ||
c980d109 ACM |
6541 | static void __perf_event_header__init_id(struct perf_event_header *header, |
6542 | struct perf_sample_data *data, | |
6543 | struct perf_event *event) | |
6844c09d ACM |
6544 | { |
6545 | u64 sample_type = event->attr.sample_type; | |
6546 | ||
6547 | data->type = sample_type; | |
6548 | header->size += event->id_header_size; | |
6549 | ||
6550 | if (sample_type & PERF_SAMPLE_TID) { | |
6551 | /* namespace issues */ | |
6552 | data->tid_entry.pid = perf_event_pid(event, current); | |
6553 | data->tid_entry.tid = perf_event_tid(event, current); | |
6554 | } | |
6555 | ||
6556 | if (sample_type & PERF_SAMPLE_TIME) | |
34f43927 | 6557 | data->time = perf_event_clock(event); |
6844c09d | 6558 | |
ff3d527c | 6559 | if (sample_type & (PERF_SAMPLE_ID | PERF_SAMPLE_IDENTIFIER)) |
6844c09d ACM |
6560 | data->id = primary_event_id(event); |
6561 | ||
6562 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6563 | data->stream_id = event->id; | |
6564 | ||
6565 | if (sample_type & PERF_SAMPLE_CPU) { | |
6566 | data->cpu_entry.cpu = raw_smp_processor_id(); | |
6567 | data->cpu_entry.reserved = 0; | |
6568 | } | |
6569 | } | |
6570 | ||
76369139 FW |
6571 | void perf_event_header__init_id(struct perf_event_header *header, |
6572 | struct perf_sample_data *data, | |
6573 | struct perf_event *event) | |
c980d109 ACM |
6574 | { |
6575 | if (event->attr.sample_id_all) | |
6576 | __perf_event_header__init_id(header, data, event); | |
6577 | } | |
6578 | ||
6579 | static void __perf_event__output_id_sample(struct perf_output_handle *handle, | |
6580 | struct perf_sample_data *data) | |
6581 | { | |
6582 | u64 sample_type = data->type; | |
6583 | ||
6584 | if (sample_type & PERF_SAMPLE_TID) | |
6585 | perf_output_put(handle, data->tid_entry); | |
6586 | ||
6587 | if (sample_type & PERF_SAMPLE_TIME) | |
6588 | perf_output_put(handle, data->time); | |
6589 | ||
6590 | if (sample_type & PERF_SAMPLE_ID) | |
6591 | perf_output_put(handle, data->id); | |
6592 | ||
6593 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6594 | perf_output_put(handle, data->stream_id); | |
6595 | ||
6596 | if (sample_type & PERF_SAMPLE_CPU) | |
6597 | perf_output_put(handle, data->cpu_entry); | |
ff3d527c AH |
6598 | |
6599 | if (sample_type & PERF_SAMPLE_IDENTIFIER) | |
6600 | perf_output_put(handle, data->id); | |
c980d109 ACM |
6601 | } |
6602 | ||
76369139 FW |
6603 | void perf_event__output_id_sample(struct perf_event *event, |
6604 | struct perf_output_handle *handle, | |
6605 | struct perf_sample_data *sample) | |
c980d109 ACM |
6606 | { |
6607 | if (event->attr.sample_id_all) | |
6608 | __perf_event__output_id_sample(handle, sample); | |
6609 | } | |
6610 | ||
3dab77fb | 6611 | static void perf_output_read_one(struct perf_output_handle *handle, |
eed01528 SE |
6612 | struct perf_event *event, |
6613 | u64 enabled, u64 running) | |
3dab77fb | 6614 | { |
cdd6c482 | 6615 | u64 read_format = event->attr.read_format; |
3dab77fb PZ |
6616 | u64 values[4]; |
6617 | int n = 0; | |
6618 | ||
b5e58793 | 6619 | values[n++] = perf_event_count(event); |
3dab77fb | 6620 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { |
eed01528 | 6621 | values[n++] = enabled + |
cdd6c482 | 6622 | atomic64_read(&event->child_total_time_enabled); |
3dab77fb PZ |
6623 | } |
6624 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { | |
eed01528 | 6625 | values[n++] = running + |
cdd6c482 | 6626 | atomic64_read(&event->child_total_time_running); |
3dab77fb PZ |
6627 | } |
6628 | if (read_format & PERF_FORMAT_ID) | |
cdd6c482 | 6629 | values[n++] = primary_event_id(event); |
3dab77fb | 6630 | |
76369139 | 6631 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
6632 | } |
6633 | ||
3dab77fb | 6634 | static void perf_output_read_group(struct perf_output_handle *handle, |
eed01528 SE |
6635 | struct perf_event *event, |
6636 | u64 enabled, u64 running) | |
3dab77fb | 6637 | { |
cdd6c482 IM |
6638 | struct perf_event *leader = event->group_leader, *sub; |
6639 | u64 read_format = event->attr.read_format; | |
3dab77fb PZ |
6640 | u64 values[5]; |
6641 | int n = 0; | |
6642 | ||
6643 | values[n++] = 1 + leader->nr_siblings; | |
6644 | ||
6645 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
eed01528 | 6646 | values[n++] = enabled; |
3dab77fb PZ |
6647 | |
6648 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
eed01528 | 6649 | values[n++] = running; |
3dab77fb | 6650 | |
9e5b127d PZ |
6651 | if ((leader != event) && |
6652 | (leader->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
6653 | leader->pmu->read(leader); |
6654 | ||
b5e58793 | 6655 | values[n++] = perf_event_count(leader); |
3dab77fb | 6656 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 6657 | values[n++] = primary_event_id(leader); |
3dab77fb | 6658 | |
76369139 | 6659 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb | 6660 | |
edb39592 | 6661 | for_each_sibling_event(sub, leader) { |
3dab77fb PZ |
6662 | n = 0; |
6663 | ||
6f5ab001 JO |
6664 | if ((sub != event) && |
6665 | (sub->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
6666 | sub->pmu->read(sub); |
6667 | ||
b5e58793 | 6668 | values[n++] = perf_event_count(sub); |
3dab77fb | 6669 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 6670 | values[n++] = primary_event_id(sub); |
3dab77fb | 6671 | |
76369139 | 6672 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
6673 | } |
6674 | } | |
6675 | ||
eed01528 SE |
6676 | #define PERF_FORMAT_TOTAL_TIMES (PERF_FORMAT_TOTAL_TIME_ENABLED|\ |
6677 | PERF_FORMAT_TOTAL_TIME_RUNNING) | |
6678 | ||
ba5213ae PZ |
6679 | /* |
6680 | * XXX PERF_SAMPLE_READ vs inherited events seems difficult. | |
6681 | * | |
6682 | * The problem is that its both hard and excessively expensive to iterate the | |
6683 | * child list, not to mention that its impossible to IPI the children running | |
6684 | * on another CPU, from interrupt/NMI context. | |
6685 | */ | |
3dab77fb | 6686 | static void perf_output_read(struct perf_output_handle *handle, |
cdd6c482 | 6687 | struct perf_event *event) |
3dab77fb | 6688 | { |
e3f3541c | 6689 | u64 enabled = 0, running = 0, now; |
eed01528 SE |
6690 | u64 read_format = event->attr.read_format; |
6691 | ||
6692 | /* | |
6693 | * compute total_time_enabled, total_time_running | |
6694 | * based on snapshot values taken when the event | |
6695 | * was last scheduled in. | |
6696 | * | |
6697 | * we cannot simply called update_context_time() | |
6698 | * because of locking issue as we are called in | |
6699 | * NMI context | |
6700 | */ | |
c4794295 | 6701 | if (read_format & PERF_FORMAT_TOTAL_TIMES) |
e3f3541c | 6702 | calc_timer_values(event, &now, &enabled, &running); |
eed01528 | 6703 | |
cdd6c482 | 6704 | if (event->attr.read_format & PERF_FORMAT_GROUP) |
eed01528 | 6705 | perf_output_read_group(handle, event, enabled, running); |
3dab77fb | 6706 | else |
eed01528 | 6707 | perf_output_read_one(handle, event, enabled, running); |
3dab77fb PZ |
6708 | } |
6709 | ||
bbfd5e4f KL |
6710 | static inline bool perf_sample_save_hw_index(struct perf_event *event) |
6711 | { | |
6712 | return event->attr.branch_sample_type & PERF_SAMPLE_BRANCH_HW_INDEX; | |
6713 | } | |
6714 | ||
5622f295 MM |
6715 | void perf_output_sample(struct perf_output_handle *handle, |
6716 | struct perf_event_header *header, | |
6717 | struct perf_sample_data *data, | |
cdd6c482 | 6718 | struct perf_event *event) |
5622f295 MM |
6719 | { |
6720 | u64 sample_type = data->type; | |
6721 | ||
6722 | perf_output_put(handle, *header); | |
6723 | ||
ff3d527c AH |
6724 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
6725 | perf_output_put(handle, data->id); | |
6726 | ||
5622f295 MM |
6727 | if (sample_type & PERF_SAMPLE_IP) |
6728 | perf_output_put(handle, data->ip); | |
6729 | ||
6730 | if (sample_type & PERF_SAMPLE_TID) | |
6731 | perf_output_put(handle, data->tid_entry); | |
6732 | ||
6733 | if (sample_type & PERF_SAMPLE_TIME) | |
6734 | perf_output_put(handle, data->time); | |
6735 | ||
6736 | if (sample_type & PERF_SAMPLE_ADDR) | |
6737 | perf_output_put(handle, data->addr); | |
6738 | ||
6739 | if (sample_type & PERF_SAMPLE_ID) | |
6740 | perf_output_put(handle, data->id); | |
6741 | ||
6742 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6743 | perf_output_put(handle, data->stream_id); | |
6744 | ||
6745 | if (sample_type & PERF_SAMPLE_CPU) | |
6746 | perf_output_put(handle, data->cpu_entry); | |
6747 | ||
6748 | if (sample_type & PERF_SAMPLE_PERIOD) | |
6749 | perf_output_put(handle, data->period); | |
6750 | ||
6751 | if (sample_type & PERF_SAMPLE_READ) | |
cdd6c482 | 6752 | perf_output_read(handle, event); |
5622f295 MM |
6753 | |
6754 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { | |
99e818cc | 6755 | int size = 1; |
5622f295 | 6756 | |
99e818cc JO |
6757 | size += data->callchain->nr; |
6758 | size *= sizeof(u64); | |
6759 | __output_copy(handle, data->callchain, size); | |
5622f295 MM |
6760 | } |
6761 | ||
6762 | if (sample_type & PERF_SAMPLE_RAW) { | |
7e3f977e DB |
6763 | struct perf_raw_record *raw = data->raw; |
6764 | ||
6765 | if (raw) { | |
6766 | struct perf_raw_frag *frag = &raw->frag; | |
6767 | ||
6768 | perf_output_put(handle, raw->size); | |
6769 | do { | |
6770 | if (frag->copy) { | |
6771 | __output_custom(handle, frag->copy, | |
6772 | frag->data, frag->size); | |
6773 | } else { | |
6774 | __output_copy(handle, frag->data, | |
6775 | frag->size); | |
6776 | } | |
6777 | if (perf_raw_frag_last(frag)) | |
6778 | break; | |
6779 | frag = frag->next; | |
6780 | } while (1); | |
6781 | if (frag->pad) | |
6782 | __output_skip(handle, NULL, frag->pad); | |
5622f295 MM |
6783 | } else { |
6784 | struct { | |
6785 | u32 size; | |
6786 | u32 data; | |
6787 | } raw = { | |
6788 | .size = sizeof(u32), | |
6789 | .data = 0, | |
6790 | }; | |
6791 | perf_output_put(handle, raw); | |
6792 | } | |
6793 | } | |
a7ac67ea | 6794 | |
bce38cd5 SE |
6795 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { |
6796 | if (data->br_stack) { | |
6797 | size_t size; | |
6798 | ||
6799 | size = data->br_stack->nr | |
6800 | * sizeof(struct perf_branch_entry); | |
6801 | ||
6802 | perf_output_put(handle, data->br_stack->nr); | |
bbfd5e4f KL |
6803 | if (perf_sample_save_hw_index(event)) |
6804 | perf_output_put(handle, data->br_stack->hw_idx); | |
bce38cd5 SE |
6805 | perf_output_copy(handle, data->br_stack->entries, size); |
6806 | } else { | |
6807 | /* | |
6808 | * we always store at least the value of nr | |
6809 | */ | |
6810 | u64 nr = 0; | |
6811 | perf_output_put(handle, nr); | |
6812 | } | |
6813 | } | |
4018994f JO |
6814 | |
6815 | if (sample_type & PERF_SAMPLE_REGS_USER) { | |
6816 | u64 abi = data->regs_user.abi; | |
6817 | ||
6818 | /* | |
6819 | * If there are no regs to dump, notice it through | |
6820 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
6821 | */ | |
6822 | perf_output_put(handle, abi); | |
6823 | ||
6824 | if (abi) { | |
6825 | u64 mask = event->attr.sample_regs_user; | |
6826 | perf_output_sample_regs(handle, | |
6827 | data->regs_user.regs, | |
6828 | mask); | |
6829 | } | |
6830 | } | |
c5ebcedb | 6831 | |
a5cdd40c | 6832 | if (sample_type & PERF_SAMPLE_STACK_USER) { |
c5ebcedb JO |
6833 | perf_output_sample_ustack(handle, |
6834 | data->stack_user_size, | |
6835 | data->regs_user.regs); | |
a5cdd40c | 6836 | } |
c3feedf2 AK |
6837 | |
6838 | if (sample_type & PERF_SAMPLE_WEIGHT) | |
6839 | perf_output_put(handle, data->weight); | |
d6be9ad6 SE |
6840 | |
6841 | if (sample_type & PERF_SAMPLE_DATA_SRC) | |
6842 | perf_output_put(handle, data->data_src.val); | |
a5cdd40c | 6843 | |
fdfbbd07 AK |
6844 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
6845 | perf_output_put(handle, data->txn); | |
6846 | ||
60e2364e SE |
6847 | if (sample_type & PERF_SAMPLE_REGS_INTR) { |
6848 | u64 abi = data->regs_intr.abi; | |
6849 | /* | |
6850 | * If there are no regs to dump, notice it through | |
6851 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
6852 | */ | |
6853 | perf_output_put(handle, abi); | |
6854 | ||
6855 | if (abi) { | |
6856 | u64 mask = event->attr.sample_regs_intr; | |
6857 | ||
6858 | perf_output_sample_regs(handle, | |
6859 | data->regs_intr.regs, | |
6860 | mask); | |
6861 | } | |
6862 | } | |
6863 | ||
fc7ce9c7 KL |
6864 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) |
6865 | perf_output_put(handle, data->phys_addr); | |
6866 | ||
a4faf00d AS |
6867 | if (sample_type & PERF_SAMPLE_AUX) { |
6868 | perf_output_put(handle, data->aux_size); | |
6869 | ||
6870 | if (data->aux_size) | |
6871 | perf_aux_sample_output(event, handle, data); | |
6872 | } | |
6873 | ||
a5cdd40c PZ |
6874 | if (!event->attr.watermark) { |
6875 | int wakeup_events = event->attr.wakeup_events; | |
6876 | ||
6877 | if (wakeup_events) { | |
56de4e8f | 6878 | struct perf_buffer *rb = handle->rb; |
a5cdd40c PZ |
6879 | int events = local_inc_return(&rb->events); |
6880 | ||
6881 | if (events >= wakeup_events) { | |
6882 | local_sub(wakeup_events, &rb->events); | |
6883 | local_inc(&rb->wakeup); | |
6884 | } | |
6885 | } | |
6886 | } | |
5622f295 MM |
6887 | } |
6888 | ||
fc7ce9c7 KL |
6889 | static u64 perf_virt_to_phys(u64 virt) |
6890 | { | |
6891 | u64 phys_addr = 0; | |
6892 | struct page *p = NULL; | |
6893 | ||
6894 | if (!virt) | |
6895 | return 0; | |
6896 | ||
6897 | if (virt >= TASK_SIZE) { | |
6898 | /* If it's vmalloc()d memory, leave phys_addr as 0 */ | |
6899 | if (virt_addr_valid((void *)(uintptr_t)virt) && | |
6900 | !(virt >= VMALLOC_START && virt < VMALLOC_END)) | |
6901 | phys_addr = (u64)virt_to_phys((void *)(uintptr_t)virt); | |
6902 | } else { | |
6903 | /* | |
6904 | * Walking the pages tables for user address. | |
6905 | * Interrupts are disabled, so it prevents any tear down | |
6906 | * of the page tables. | |
6907 | * Try IRQ-safe __get_user_pages_fast first. | |
6908 | * If failed, leave phys_addr as 0. | |
6909 | */ | |
6910 | if ((current->mm != NULL) && | |
6911 | (__get_user_pages_fast(virt, 1, 0, &p) == 1)) | |
6912 | phys_addr = page_to_phys(p) + virt % PAGE_SIZE; | |
6913 | ||
6914 | if (p) | |
6915 | put_page(p); | |
6916 | } | |
6917 | ||
6918 | return phys_addr; | |
6919 | } | |
6920 | ||
99e818cc JO |
6921 | static struct perf_callchain_entry __empty_callchain = { .nr = 0, }; |
6922 | ||
6cbc304f | 6923 | struct perf_callchain_entry * |
8cf7e0e2 JO |
6924 | perf_callchain(struct perf_event *event, struct pt_regs *regs) |
6925 | { | |
6926 | bool kernel = !event->attr.exclude_callchain_kernel; | |
6927 | bool user = !event->attr.exclude_callchain_user; | |
6928 | /* Disallow cross-task user callchains. */ | |
6929 | bool crosstask = event->ctx->task && event->ctx->task != current; | |
6930 | const u32 max_stack = event->attr.sample_max_stack; | |
99e818cc | 6931 | struct perf_callchain_entry *callchain; |
8cf7e0e2 JO |
6932 | |
6933 | if (!kernel && !user) | |
99e818cc | 6934 | return &__empty_callchain; |
8cf7e0e2 | 6935 | |
99e818cc JO |
6936 | callchain = get_perf_callchain(regs, 0, kernel, user, |
6937 | max_stack, crosstask, true); | |
6938 | return callchain ?: &__empty_callchain; | |
8cf7e0e2 JO |
6939 | } |
6940 | ||
5622f295 MM |
6941 | void perf_prepare_sample(struct perf_event_header *header, |
6942 | struct perf_sample_data *data, | |
cdd6c482 | 6943 | struct perf_event *event, |
5622f295 | 6944 | struct pt_regs *regs) |
7b732a75 | 6945 | { |
cdd6c482 | 6946 | u64 sample_type = event->attr.sample_type; |
7b732a75 | 6947 | |
cdd6c482 | 6948 | header->type = PERF_RECORD_SAMPLE; |
c320c7b7 | 6949 | header->size = sizeof(*header) + event->header_size; |
5622f295 MM |
6950 | |
6951 | header->misc = 0; | |
6952 | header->misc |= perf_misc_flags(regs); | |
6fab0192 | 6953 | |
c980d109 | 6954 | __perf_event_header__init_id(header, data, event); |
6844c09d | 6955 | |
c320c7b7 | 6956 | if (sample_type & PERF_SAMPLE_IP) |
5622f295 MM |
6957 | data->ip = perf_instruction_pointer(regs); |
6958 | ||
b23f3325 | 6959 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { |
5622f295 | 6960 | int size = 1; |
394ee076 | 6961 | |
6cbc304f PZ |
6962 | if (!(sample_type & __PERF_SAMPLE_CALLCHAIN_EARLY)) |
6963 | data->callchain = perf_callchain(event, regs); | |
6964 | ||
99e818cc | 6965 | size += data->callchain->nr; |
5622f295 MM |
6966 | |
6967 | header->size += size * sizeof(u64); | |
394ee076 PZ |
6968 | } |
6969 | ||
3a43ce68 | 6970 | if (sample_type & PERF_SAMPLE_RAW) { |
7e3f977e DB |
6971 | struct perf_raw_record *raw = data->raw; |
6972 | int size; | |
6973 | ||
6974 | if (raw) { | |
6975 | struct perf_raw_frag *frag = &raw->frag; | |
6976 | u32 sum = 0; | |
6977 | ||
6978 | do { | |
6979 | sum += frag->size; | |
6980 | if (perf_raw_frag_last(frag)) | |
6981 | break; | |
6982 | frag = frag->next; | |
6983 | } while (1); | |
6984 | ||
6985 | size = round_up(sum + sizeof(u32), sizeof(u64)); | |
6986 | raw->size = size - sizeof(u32); | |
6987 | frag->pad = raw->size - sum; | |
6988 | } else { | |
6989 | size = sizeof(u64); | |
6990 | } | |
a044560c | 6991 | |
7e3f977e | 6992 | header->size += size; |
7f453c24 | 6993 | } |
bce38cd5 SE |
6994 | |
6995 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { | |
6996 | int size = sizeof(u64); /* nr */ | |
6997 | if (data->br_stack) { | |
bbfd5e4f KL |
6998 | if (perf_sample_save_hw_index(event)) |
6999 | size += sizeof(u64); | |
7000 | ||
bce38cd5 SE |
7001 | size += data->br_stack->nr |
7002 | * sizeof(struct perf_branch_entry); | |
7003 | } | |
7004 | header->size += size; | |
7005 | } | |
4018994f | 7006 | |
2565711f | 7007 | if (sample_type & (PERF_SAMPLE_REGS_USER | PERF_SAMPLE_STACK_USER)) |
88a7c26a AL |
7008 | perf_sample_regs_user(&data->regs_user, regs, |
7009 | &data->regs_user_copy); | |
2565711f | 7010 | |
4018994f JO |
7011 | if (sample_type & PERF_SAMPLE_REGS_USER) { |
7012 | /* regs dump ABI info */ | |
7013 | int size = sizeof(u64); | |
7014 | ||
4018994f JO |
7015 | if (data->regs_user.regs) { |
7016 | u64 mask = event->attr.sample_regs_user; | |
7017 | size += hweight64(mask) * sizeof(u64); | |
7018 | } | |
7019 | ||
7020 | header->size += size; | |
7021 | } | |
c5ebcedb JO |
7022 | |
7023 | if (sample_type & PERF_SAMPLE_STACK_USER) { | |
7024 | /* | |
9f014e3a | 7025 | * Either we need PERF_SAMPLE_STACK_USER bit to be always |
c5ebcedb JO |
7026 | * processed as the last one or have additional check added |
7027 | * in case new sample type is added, because we could eat | |
7028 | * up the rest of the sample size. | |
7029 | */ | |
c5ebcedb JO |
7030 | u16 stack_size = event->attr.sample_stack_user; |
7031 | u16 size = sizeof(u64); | |
7032 | ||
c5ebcedb | 7033 | stack_size = perf_sample_ustack_size(stack_size, header->size, |
2565711f | 7034 | data->regs_user.regs); |
c5ebcedb JO |
7035 | |
7036 | /* | |
7037 | * If there is something to dump, add space for the dump | |
7038 | * itself and for the field that tells the dynamic size, | |
7039 | * which is how many have been actually dumped. | |
7040 | */ | |
7041 | if (stack_size) | |
7042 | size += sizeof(u64) + stack_size; | |
7043 | ||
7044 | data->stack_user_size = stack_size; | |
7045 | header->size += size; | |
7046 | } | |
60e2364e SE |
7047 | |
7048 | if (sample_type & PERF_SAMPLE_REGS_INTR) { | |
7049 | /* regs dump ABI info */ | |
7050 | int size = sizeof(u64); | |
7051 | ||
7052 | perf_sample_regs_intr(&data->regs_intr, regs); | |
7053 | ||
7054 | if (data->regs_intr.regs) { | |
7055 | u64 mask = event->attr.sample_regs_intr; | |
7056 | ||
7057 | size += hweight64(mask) * sizeof(u64); | |
7058 | } | |
7059 | ||
7060 | header->size += size; | |
7061 | } | |
fc7ce9c7 KL |
7062 | |
7063 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) | |
7064 | data->phys_addr = perf_virt_to_phys(data->addr); | |
a4faf00d AS |
7065 | |
7066 | if (sample_type & PERF_SAMPLE_AUX) { | |
7067 | u64 size; | |
7068 | ||
7069 | header->size += sizeof(u64); /* size */ | |
7070 | ||
7071 | /* | |
7072 | * Given the 16bit nature of header::size, an AUX sample can | |
7073 | * easily overflow it, what with all the preceding sample bits. | |
7074 | * Make sure this doesn't happen by using up to U16_MAX bytes | |
7075 | * per sample in total (rounded down to 8 byte boundary). | |
7076 | */ | |
7077 | size = min_t(size_t, U16_MAX - header->size, | |
7078 | event->attr.aux_sample_size); | |
7079 | size = rounddown(size, 8); | |
7080 | size = perf_prepare_sample_aux(event, data, size); | |
7081 | ||
7082 | WARN_ON_ONCE(size + header->size > U16_MAX); | |
7083 | header->size += size; | |
7084 | } | |
7085 | /* | |
7086 | * If you're adding more sample types here, you likely need to do | |
7087 | * something about the overflowing header::size, like repurpose the | |
7088 | * lowest 3 bits of size, which should be always zero at the moment. | |
7089 | * This raises a more important question, do we really need 512k sized | |
7090 | * samples and why, so good argumentation is in order for whatever you | |
7091 | * do here next. | |
7092 | */ | |
7093 | WARN_ON_ONCE(header->size & 7); | |
5622f295 | 7094 | } |
7f453c24 | 7095 | |
56201969 | 7096 | static __always_inline int |
9ecda41a WN |
7097 | __perf_event_output(struct perf_event *event, |
7098 | struct perf_sample_data *data, | |
7099 | struct pt_regs *regs, | |
7100 | int (*output_begin)(struct perf_output_handle *, | |
7101 | struct perf_event *, | |
7102 | unsigned int)) | |
5622f295 MM |
7103 | { |
7104 | struct perf_output_handle handle; | |
7105 | struct perf_event_header header; | |
56201969 | 7106 | int err; |
689802b2 | 7107 | |
927c7a9e FW |
7108 | /* protect the callchain buffers */ |
7109 | rcu_read_lock(); | |
7110 | ||
cdd6c482 | 7111 | perf_prepare_sample(&header, data, event, regs); |
5c148194 | 7112 | |
56201969 ACM |
7113 | err = output_begin(&handle, event, header.size); |
7114 | if (err) | |
927c7a9e | 7115 | goto exit; |
0322cd6e | 7116 | |
cdd6c482 | 7117 | perf_output_sample(&handle, &header, data, event); |
f413cdb8 | 7118 | |
8a057d84 | 7119 | perf_output_end(&handle); |
927c7a9e FW |
7120 | |
7121 | exit: | |
7122 | rcu_read_unlock(); | |
56201969 | 7123 | return err; |
0322cd6e PZ |
7124 | } |
7125 | ||
9ecda41a WN |
7126 | void |
7127 | perf_event_output_forward(struct perf_event *event, | |
7128 | struct perf_sample_data *data, | |
7129 | struct pt_regs *regs) | |
7130 | { | |
7131 | __perf_event_output(event, data, regs, perf_output_begin_forward); | |
7132 | } | |
7133 | ||
7134 | void | |
7135 | perf_event_output_backward(struct perf_event *event, | |
7136 | struct perf_sample_data *data, | |
7137 | struct pt_regs *regs) | |
7138 | { | |
7139 | __perf_event_output(event, data, regs, perf_output_begin_backward); | |
7140 | } | |
7141 | ||
56201969 | 7142 | int |
9ecda41a WN |
7143 | perf_event_output(struct perf_event *event, |
7144 | struct perf_sample_data *data, | |
7145 | struct pt_regs *regs) | |
7146 | { | |
56201969 | 7147 | return __perf_event_output(event, data, regs, perf_output_begin); |
9ecda41a WN |
7148 | } |
7149 | ||
38b200d6 | 7150 | /* |
cdd6c482 | 7151 | * read event_id |
38b200d6 PZ |
7152 | */ |
7153 | ||
7154 | struct perf_read_event { | |
7155 | struct perf_event_header header; | |
7156 | ||
7157 | u32 pid; | |
7158 | u32 tid; | |
38b200d6 PZ |
7159 | }; |
7160 | ||
7161 | static void | |
cdd6c482 | 7162 | perf_event_read_event(struct perf_event *event, |
38b200d6 PZ |
7163 | struct task_struct *task) |
7164 | { | |
7165 | struct perf_output_handle handle; | |
c980d109 | 7166 | struct perf_sample_data sample; |
dfc65094 | 7167 | struct perf_read_event read_event = { |
38b200d6 | 7168 | .header = { |
cdd6c482 | 7169 | .type = PERF_RECORD_READ, |
38b200d6 | 7170 | .misc = 0, |
c320c7b7 | 7171 | .size = sizeof(read_event) + event->read_size, |
38b200d6 | 7172 | }, |
cdd6c482 IM |
7173 | .pid = perf_event_pid(event, task), |
7174 | .tid = perf_event_tid(event, task), | |
38b200d6 | 7175 | }; |
3dab77fb | 7176 | int ret; |
38b200d6 | 7177 | |
c980d109 | 7178 | perf_event_header__init_id(&read_event.header, &sample, event); |
a7ac67ea | 7179 | ret = perf_output_begin(&handle, event, read_event.header.size); |
38b200d6 PZ |
7180 | if (ret) |
7181 | return; | |
7182 | ||
dfc65094 | 7183 | perf_output_put(&handle, read_event); |
cdd6c482 | 7184 | perf_output_read(&handle, event); |
c980d109 | 7185 | perf_event__output_id_sample(event, &handle, &sample); |
3dab77fb | 7186 | |
38b200d6 PZ |
7187 | perf_output_end(&handle); |
7188 | } | |
7189 | ||
aab5b71e | 7190 | typedef void (perf_iterate_f)(struct perf_event *event, void *data); |
52d857a8 JO |
7191 | |
7192 | static void | |
aab5b71e PZ |
7193 | perf_iterate_ctx(struct perf_event_context *ctx, |
7194 | perf_iterate_f output, | |
b73e4fef | 7195 | void *data, bool all) |
52d857a8 JO |
7196 | { |
7197 | struct perf_event *event; | |
7198 | ||
7199 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
b73e4fef AS |
7200 | if (!all) { |
7201 | if (event->state < PERF_EVENT_STATE_INACTIVE) | |
7202 | continue; | |
7203 | if (!event_filter_match(event)) | |
7204 | continue; | |
7205 | } | |
7206 | ||
67516844 | 7207 | output(event, data); |
52d857a8 JO |
7208 | } |
7209 | } | |
7210 | ||
aab5b71e | 7211 | static void perf_iterate_sb_cpu(perf_iterate_f output, void *data) |
f2fb6bef KL |
7212 | { |
7213 | struct pmu_event_list *pel = this_cpu_ptr(&pmu_sb_events); | |
7214 | struct perf_event *event; | |
7215 | ||
7216 | list_for_each_entry_rcu(event, &pel->list, sb_list) { | |
0b8f1e2e PZ |
7217 | /* |
7218 | * Skip events that are not fully formed yet; ensure that | |
7219 | * if we observe event->ctx, both event and ctx will be | |
7220 | * complete enough. See perf_install_in_context(). | |
7221 | */ | |
7222 | if (!smp_load_acquire(&event->ctx)) | |
7223 | continue; | |
7224 | ||
f2fb6bef KL |
7225 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
7226 | continue; | |
7227 | if (!event_filter_match(event)) | |
7228 | continue; | |
7229 | output(event, data); | |
7230 | } | |
7231 | } | |
7232 | ||
aab5b71e PZ |
7233 | /* |
7234 | * Iterate all events that need to receive side-band events. | |
7235 | * | |
7236 | * For new callers; ensure that account_pmu_sb_event() includes | |
7237 | * your event, otherwise it might not get delivered. | |
7238 | */ | |
52d857a8 | 7239 | static void |
aab5b71e | 7240 | perf_iterate_sb(perf_iterate_f output, void *data, |
52d857a8 JO |
7241 | struct perf_event_context *task_ctx) |
7242 | { | |
52d857a8 | 7243 | struct perf_event_context *ctx; |
52d857a8 JO |
7244 | int ctxn; |
7245 | ||
aab5b71e PZ |
7246 | rcu_read_lock(); |
7247 | preempt_disable(); | |
7248 | ||
4e93ad60 | 7249 | /* |
aab5b71e PZ |
7250 | * If we have task_ctx != NULL we only notify the task context itself. |
7251 | * The task_ctx is set only for EXIT events before releasing task | |
4e93ad60 JO |
7252 | * context. |
7253 | */ | |
7254 | if (task_ctx) { | |
aab5b71e PZ |
7255 | perf_iterate_ctx(task_ctx, output, data, false); |
7256 | goto done; | |
4e93ad60 JO |
7257 | } |
7258 | ||
aab5b71e | 7259 | perf_iterate_sb_cpu(output, data); |
f2fb6bef KL |
7260 | |
7261 | for_each_task_context_nr(ctxn) { | |
52d857a8 JO |
7262 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); |
7263 | if (ctx) | |
aab5b71e | 7264 | perf_iterate_ctx(ctx, output, data, false); |
52d857a8 | 7265 | } |
aab5b71e | 7266 | done: |
f2fb6bef | 7267 | preempt_enable(); |
52d857a8 | 7268 | rcu_read_unlock(); |
95ff4ca2 AS |
7269 | } |
7270 | ||
375637bc AS |
7271 | /* |
7272 | * Clear all file-based filters at exec, they'll have to be | |
7273 | * re-instated when/if these objects are mmapped again. | |
7274 | */ | |
7275 | static void perf_event_addr_filters_exec(struct perf_event *event, void *data) | |
7276 | { | |
7277 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
7278 | struct perf_addr_filter *filter; | |
7279 | unsigned int restart = 0, count = 0; | |
7280 | unsigned long flags; | |
7281 | ||
7282 | if (!has_addr_filter(event)) | |
7283 | return; | |
7284 | ||
7285 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
7286 | list_for_each_entry(filter, &ifh->list, entry) { | |
9511bce9 | 7287 | if (filter->path.dentry) { |
c60f83b8 AS |
7288 | event->addr_filter_ranges[count].start = 0; |
7289 | event->addr_filter_ranges[count].size = 0; | |
375637bc AS |
7290 | restart++; |
7291 | } | |
7292 | ||
7293 | count++; | |
7294 | } | |
7295 | ||
7296 | if (restart) | |
7297 | event->addr_filters_gen++; | |
7298 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
7299 | ||
7300 | if (restart) | |
767ae086 | 7301 | perf_event_stop(event, 1); |
375637bc AS |
7302 | } |
7303 | ||
7304 | void perf_event_exec(void) | |
7305 | { | |
7306 | struct perf_event_context *ctx; | |
7307 | int ctxn; | |
7308 | ||
7309 | rcu_read_lock(); | |
7310 | for_each_task_context_nr(ctxn) { | |
7311 | ctx = current->perf_event_ctxp[ctxn]; | |
7312 | if (!ctx) | |
7313 | continue; | |
7314 | ||
7315 | perf_event_enable_on_exec(ctxn); | |
7316 | ||
aab5b71e | 7317 | perf_iterate_ctx(ctx, perf_event_addr_filters_exec, NULL, |
375637bc AS |
7318 | true); |
7319 | } | |
7320 | rcu_read_unlock(); | |
7321 | } | |
7322 | ||
95ff4ca2 | 7323 | struct remote_output { |
56de4e8f | 7324 | struct perf_buffer *rb; |
95ff4ca2 AS |
7325 | int err; |
7326 | }; | |
7327 | ||
7328 | static void __perf_event_output_stop(struct perf_event *event, void *data) | |
7329 | { | |
7330 | struct perf_event *parent = event->parent; | |
7331 | struct remote_output *ro = data; | |
56de4e8f | 7332 | struct perf_buffer *rb = ro->rb; |
375637bc AS |
7333 | struct stop_event_data sd = { |
7334 | .event = event, | |
7335 | }; | |
95ff4ca2 AS |
7336 | |
7337 | if (!has_aux(event)) | |
7338 | return; | |
7339 | ||
7340 | if (!parent) | |
7341 | parent = event; | |
7342 | ||
7343 | /* | |
7344 | * In case of inheritance, it will be the parent that links to the | |
767ae086 AS |
7345 | * ring-buffer, but it will be the child that's actually using it. |
7346 | * | |
7347 | * We are using event::rb to determine if the event should be stopped, | |
7348 | * however this may race with ring_buffer_attach() (through set_output), | |
7349 | * which will make us skip the event that actually needs to be stopped. | |
7350 | * So ring_buffer_attach() has to stop an aux event before re-assigning | |
7351 | * its rb pointer. | |
95ff4ca2 AS |
7352 | */ |
7353 | if (rcu_dereference(parent->rb) == rb) | |
375637bc | 7354 | ro->err = __perf_event_stop(&sd); |
95ff4ca2 AS |
7355 | } |
7356 | ||
7357 | static int __perf_pmu_output_stop(void *info) | |
7358 | { | |
7359 | struct perf_event *event = info; | |
f3a519e4 | 7360 | struct pmu *pmu = event->ctx->pmu; |
8b6a3fe8 | 7361 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
95ff4ca2 AS |
7362 | struct remote_output ro = { |
7363 | .rb = event->rb, | |
7364 | }; | |
7365 | ||
7366 | rcu_read_lock(); | |
aab5b71e | 7367 | perf_iterate_ctx(&cpuctx->ctx, __perf_event_output_stop, &ro, false); |
95ff4ca2 | 7368 | if (cpuctx->task_ctx) |
aab5b71e | 7369 | perf_iterate_ctx(cpuctx->task_ctx, __perf_event_output_stop, |
b73e4fef | 7370 | &ro, false); |
95ff4ca2 AS |
7371 | rcu_read_unlock(); |
7372 | ||
7373 | return ro.err; | |
7374 | } | |
7375 | ||
7376 | static void perf_pmu_output_stop(struct perf_event *event) | |
7377 | { | |
7378 | struct perf_event *iter; | |
7379 | int err, cpu; | |
7380 | ||
7381 | restart: | |
7382 | rcu_read_lock(); | |
7383 | list_for_each_entry_rcu(iter, &event->rb->event_list, rb_entry) { | |
7384 | /* | |
7385 | * For per-CPU events, we need to make sure that neither they | |
7386 | * nor their children are running; for cpu==-1 events it's | |
7387 | * sufficient to stop the event itself if it's active, since | |
7388 | * it can't have children. | |
7389 | */ | |
7390 | cpu = iter->cpu; | |
7391 | if (cpu == -1) | |
7392 | cpu = READ_ONCE(iter->oncpu); | |
7393 | ||
7394 | if (cpu == -1) | |
7395 | continue; | |
7396 | ||
7397 | err = cpu_function_call(cpu, __perf_pmu_output_stop, event); | |
7398 | if (err == -EAGAIN) { | |
7399 | rcu_read_unlock(); | |
7400 | goto restart; | |
7401 | } | |
7402 | } | |
7403 | rcu_read_unlock(); | |
52d857a8 JO |
7404 | } |
7405 | ||
60313ebe | 7406 | /* |
9f498cc5 PZ |
7407 | * task tracking -- fork/exit |
7408 | * | |
13d7a241 | 7409 | * enabled by: attr.comm | attr.mmap | attr.mmap2 | attr.mmap_data | attr.task |
60313ebe PZ |
7410 | */ |
7411 | ||
9f498cc5 | 7412 | struct perf_task_event { |
3a80b4a3 | 7413 | struct task_struct *task; |
cdd6c482 | 7414 | struct perf_event_context *task_ctx; |
60313ebe PZ |
7415 | |
7416 | struct { | |
7417 | struct perf_event_header header; | |
7418 | ||
7419 | u32 pid; | |
7420 | u32 ppid; | |
9f498cc5 PZ |
7421 | u32 tid; |
7422 | u32 ptid; | |
393b2ad8 | 7423 | u64 time; |
cdd6c482 | 7424 | } event_id; |
60313ebe PZ |
7425 | }; |
7426 | ||
67516844 JO |
7427 | static int perf_event_task_match(struct perf_event *event) |
7428 | { | |
13d7a241 SE |
7429 | return event->attr.comm || event->attr.mmap || |
7430 | event->attr.mmap2 || event->attr.mmap_data || | |
7431 | event->attr.task; | |
67516844 JO |
7432 | } |
7433 | ||
cdd6c482 | 7434 | static void perf_event_task_output(struct perf_event *event, |
52d857a8 | 7435 | void *data) |
60313ebe | 7436 | { |
52d857a8 | 7437 | struct perf_task_event *task_event = data; |
60313ebe | 7438 | struct perf_output_handle handle; |
c980d109 | 7439 | struct perf_sample_data sample; |
9f498cc5 | 7440 | struct task_struct *task = task_event->task; |
c980d109 | 7441 | int ret, size = task_event->event_id.header.size; |
8bb39f9a | 7442 | |
67516844 JO |
7443 | if (!perf_event_task_match(event)) |
7444 | return; | |
7445 | ||
c980d109 | 7446 | perf_event_header__init_id(&task_event->event_id.header, &sample, event); |
60313ebe | 7447 | |
c980d109 | 7448 | ret = perf_output_begin(&handle, event, |
a7ac67ea | 7449 | task_event->event_id.header.size); |
ef60777c | 7450 | if (ret) |
c980d109 | 7451 | goto out; |
60313ebe | 7452 | |
cdd6c482 IM |
7453 | task_event->event_id.pid = perf_event_pid(event, task); |
7454 | task_event->event_id.ppid = perf_event_pid(event, current); | |
60313ebe | 7455 | |
cdd6c482 IM |
7456 | task_event->event_id.tid = perf_event_tid(event, task); |
7457 | task_event->event_id.ptid = perf_event_tid(event, current); | |
9f498cc5 | 7458 | |
34f43927 PZ |
7459 | task_event->event_id.time = perf_event_clock(event); |
7460 | ||
cdd6c482 | 7461 | perf_output_put(&handle, task_event->event_id); |
393b2ad8 | 7462 | |
c980d109 ACM |
7463 | perf_event__output_id_sample(event, &handle, &sample); |
7464 | ||
60313ebe | 7465 | perf_output_end(&handle); |
c980d109 ACM |
7466 | out: |
7467 | task_event->event_id.header.size = size; | |
60313ebe PZ |
7468 | } |
7469 | ||
cdd6c482 IM |
7470 | static void perf_event_task(struct task_struct *task, |
7471 | struct perf_event_context *task_ctx, | |
3a80b4a3 | 7472 | int new) |
60313ebe | 7473 | { |
9f498cc5 | 7474 | struct perf_task_event task_event; |
60313ebe | 7475 | |
cdd6c482 IM |
7476 | if (!atomic_read(&nr_comm_events) && |
7477 | !atomic_read(&nr_mmap_events) && | |
7478 | !atomic_read(&nr_task_events)) | |
60313ebe PZ |
7479 | return; |
7480 | ||
9f498cc5 | 7481 | task_event = (struct perf_task_event){ |
3a80b4a3 PZ |
7482 | .task = task, |
7483 | .task_ctx = task_ctx, | |
cdd6c482 | 7484 | .event_id = { |
60313ebe | 7485 | .header = { |
cdd6c482 | 7486 | .type = new ? PERF_RECORD_FORK : PERF_RECORD_EXIT, |
573402db | 7487 | .misc = 0, |
cdd6c482 | 7488 | .size = sizeof(task_event.event_id), |
60313ebe | 7489 | }, |
573402db PZ |
7490 | /* .pid */ |
7491 | /* .ppid */ | |
9f498cc5 PZ |
7492 | /* .tid */ |
7493 | /* .ptid */ | |
34f43927 | 7494 | /* .time */ |
60313ebe PZ |
7495 | }, |
7496 | }; | |
7497 | ||
aab5b71e | 7498 | perf_iterate_sb(perf_event_task_output, |
52d857a8 JO |
7499 | &task_event, |
7500 | task_ctx); | |
9f498cc5 PZ |
7501 | } |
7502 | ||
cdd6c482 | 7503 | void perf_event_fork(struct task_struct *task) |
9f498cc5 | 7504 | { |
cdd6c482 | 7505 | perf_event_task(task, NULL, 1); |
e4222673 | 7506 | perf_event_namespaces(task); |
60313ebe PZ |
7507 | } |
7508 | ||
8d1b2d93 PZ |
7509 | /* |
7510 | * comm tracking | |
7511 | */ | |
7512 | ||
7513 | struct perf_comm_event { | |
22a4f650 IM |
7514 | struct task_struct *task; |
7515 | char *comm; | |
8d1b2d93 PZ |
7516 | int comm_size; |
7517 | ||
7518 | struct { | |
7519 | struct perf_event_header header; | |
7520 | ||
7521 | u32 pid; | |
7522 | u32 tid; | |
cdd6c482 | 7523 | } event_id; |
8d1b2d93 PZ |
7524 | }; |
7525 | ||
67516844 JO |
7526 | static int perf_event_comm_match(struct perf_event *event) |
7527 | { | |
7528 | return event->attr.comm; | |
7529 | } | |
7530 | ||
cdd6c482 | 7531 | static void perf_event_comm_output(struct perf_event *event, |
52d857a8 | 7532 | void *data) |
8d1b2d93 | 7533 | { |
52d857a8 | 7534 | struct perf_comm_event *comm_event = data; |
8d1b2d93 | 7535 | struct perf_output_handle handle; |
c980d109 | 7536 | struct perf_sample_data sample; |
cdd6c482 | 7537 | int size = comm_event->event_id.header.size; |
c980d109 ACM |
7538 | int ret; |
7539 | ||
67516844 JO |
7540 | if (!perf_event_comm_match(event)) |
7541 | return; | |
7542 | ||
c980d109 ACM |
7543 | perf_event_header__init_id(&comm_event->event_id.header, &sample, event); |
7544 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 7545 | comm_event->event_id.header.size); |
8d1b2d93 PZ |
7546 | |
7547 | if (ret) | |
c980d109 | 7548 | goto out; |
8d1b2d93 | 7549 | |
cdd6c482 IM |
7550 | comm_event->event_id.pid = perf_event_pid(event, comm_event->task); |
7551 | comm_event->event_id.tid = perf_event_tid(event, comm_event->task); | |
709e50cf | 7552 | |
cdd6c482 | 7553 | perf_output_put(&handle, comm_event->event_id); |
76369139 | 7554 | __output_copy(&handle, comm_event->comm, |
8d1b2d93 | 7555 | comm_event->comm_size); |
c980d109 ACM |
7556 | |
7557 | perf_event__output_id_sample(event, &handle, &sample); | |
7558 | ||
8d1b2d93 | 7559 | perf_output_end(&handle); |
c980d109 ACM |
7560 | out: |
7561 | comm_event->event_id.header.size = size; | |
8d1b2d93 PZ |
7562 | } |
7563 | ||
cdd6c482 | 7564 | static void perf_event_comm_event(struct perf_comm_event *comm_event) |
8d1b2d93 | 7565 | { |
413ee3b4 | 7566 | char comm[TASK_COMM_LEN]; |
8d1b2d93 | 7567 | unsigned int size; |
8d1b2d93 | 7568 | |
413ee3b4 | 7569 | memset(comm, 0, sizeof(comm)); |
96b02d78 | 7570 | strlcpy(comm, comm_event->task->comm, sizeof(comm)); |
888fcee0 | 7571 | size = ALIGN(strlen(comm)+1, sizeof(u64)); |
8d1b2d93 PZ |
7572 | |
7573 | comm_event->comm = comm; | |
7574 | comm_event->comm_size = size; | |
7575 | ||
cdd6c482 | 7576 | comm_event->event_id.header.size = sizeof(comm_event->event_id) + size; |
8dc85d54 | 7577 | |
aab5b71e | 7578 | perf_iterate_sb(perf_event_comm_output, |
52d857a8 JO |
7579 | comm_event, |
7580 | NULL); | |
8d1b2d93 PZ |
7581 | } |
7582 | ||
82b89778 | 7583 | void perf_event_comm(struct task_struct *task, bool exec) |
8d1b2d93 | 7584 | { |
9ee318a7 PZ |
7585 | struct perf_comm_event comm_event; |
7586 | ||
cdd6c482 | 7587 | if (!atomic_read(&nr_comm_events)) |
9ee318a7 | 7588 | return; |
a63eaf34 | 7589 | |
9ee318a7 | 7590 | comm_event = (struct perf_comm_event){ |
8d1b2d93 | 7591 | .task = task, |
573402db PZ |
7592 | /* .comm */ |
7593 | /* .comm_size */ | |
cdd6c482 | 7594 | .event_id = { |
573402db | 7595 | .header = { |
cdd6c482 | 7596 | .type = PERF_RECORD_COMM, |
82b89778 | 7597 | .misc = exec ? PERF_RECORD_MISC_COMM_EXEC : 0, |
573402db PZ |
7598 | /* .size */ |
7599 | }, | |
7600 | /* .pid */ | |
7601 | /* .tid */ | |
8d1b2d93 PZ |
7602 | }, |
7603 | }; | |
7604 | ||
cdd6c482 | 7605 | perf_event_comm_event(&comm_event); |
8d1b2d93 PZ |
7606 | } |
7607 | ||
e4222673 HB |
7608 | /* |
7609 | * namespaces tracking | |
7610 | */ | |
7611 | ||
7612 | struct perf_namespaces_event { | |
7613 | struct task_struct *task; | |
7614 | ||
7615 | struct { | |
7616 | struct perf_event_header header; | |
7617 | ||
7618 | u32 pid; | |
7619 | u32 tid; | |
7620 | u64 nr_namespaces; | |
7621 | struct perf_ns_link_info link_info[NR_NAMESPACES]; | |
7622 | } event_id; | |
7623 | }; | |
7624 | ||
7625 | static int perf_event_namespaces_match(struct perf_event *event) | |
7626 | { | |
7627 | return event->attr.namespaces; | |
7628 | } | |
7629 | ||
7630 | static void perf_event_namespaces_output(struct perf_event *event, | |
7631 | void *data) | |
7632 | { | |
7633 | struct perf_namespaces_event *namespaces_event = data; | |
7634 | struct perf_output_handle handle; | |
7635 | struct perf_sample_data sample; | |
34900ec5 | 7636 | u16 header_size = namespaces_event->event_id.header.size; |
e4222673 HB |
7637 | int ret; |
7638 | ||
7639 | if (!perf_event_namespaces_match(event)) | |
7640 | return; | |
7641 | ||
7642 | perf_event_header__init_id(&namespaces_event->event_id.header, | |
7643 | &sample, event); | |
7644 | ret = perf_output_begin(&handle, event, | |
7645 | namespaces_event->event_id.header.size); | |
7646 | if (ret) | |
34900ec5 | 7647 | goto out; |
e4222673 HB |
7648 | |
7649 | namespaces_event->event_id.pid = perf_event_pid(event, | |
7650 | namespaces_event->task); | |
7651 | namespaces_event->event_id.tid = perf_event_tid(event, | |
7652 | namespaces_event->task); | |
7653 | ||
7654 | perf_output_put(&handle, namespaces_event->event_id); | |
7655 | ||
7656 | perf_event__output_id_sample(event, &handle, &sample); | |
7657 | ||
7658 | perf_output_end(&handle); | |
34900ec5 JO |
7659 | out: |
7660 | namespaces_event->event_id.header.size = header_size; | |
e4222673 HB |
7661 | } |
7662 | ||
7663 | static void perf_fill_ns_link_info(struct perf_ns_link_info *ns_link_info, | |
7664 | struct task_struct *task, | |
7665 | const struct proc_ns_operations *ns_ops) | |
7666 | { | |
7667 | struct path ns_path; | |
7668 | struct inode *ns_inode; | |
ce623f89 | 7669 | int error; |
e4222673 HB |
7670 | |
7671 | error = ns_get_path(&ns_path, task, ns_ops); | |
7672 | if (!error) { | |
7673 | ns_inode = ns_path.dentry->d_inode; | |
7674 | ns_link_info->dev = new_encode_dev(ns_inode->i_sb->s_dev); | |
7675 | ns_link_info->ino = ns_inode->i_ino; | |
0e18dd12 | 7676 | path_put(&ns_path); |
e4222673 HB |
7677 | } |
7678 | } | |
7679 | ||
7680 | void perf_event_namespaces(struct task_struct *task) | |
7681 | { | |
7682 | struct perf_namespaces_event namespaces_event; | |
7683 | struct perf_ns_link_info *ns_link_info; | |
7684 | ||
7685 | if (!atomic_read(&nr_namespaces_events)) | |
7686 | return; | |
7687 | ||
7688 | namespaces_event = (struct perf_namespaces_event){ | |
7689 | .task = task, | |
7690 | .event_id = { | |
7691 | .header = { | |
7692 | .type = PERF_RECORD_NAMESPACES, | |
7693 | .misc = 0, | |
7694 | .size = sizeof(namespaces_event.event_id), | |
7695 | }, | |
7696 | /* .pid */ | |
7697 | /* .tid */ | |
7698 | .nr_namespaces = NR_NAMESPACES, | |
7699 | /* .link_info[NR_NAMESPACES] */ | |
7700 | }, | |
7701 | }; | |
7702 | ||
7703 | ns_link_info = namespaces_event.event_id.link_info; | |
7704 | ||
7705 | perf_fill_ns_link_info(&ns_link_info[MNT_NS_INDEX], | |
7706 | task, &mntns_operations); | |
7707 | ||
7708 | #ifdef CONFIG_USER_NS | |
7709 | perf_fill_ns_link_info(&ns_link_info[USER_NS_INDEX], | |
7710 | task, &userns_operations); | |
7711 | #endif | |
7712 | #ifdef CONFIG_NET_NS | |
7713 | perf_fill_ns_link_info(&ns_link_info[NET_NS_INDEX], | |
7714 | task, &netns_operations); | |
7715 | #endif | |
7716 | #ifdef CONFIG_UTS_NS | |
7717 | perf_fill_ns_link_info(&ns_link_info[UTS_NS_INDEX], | |
7718 | task, &utsns_operations); | |
7719 | #endif | |
7720 | #ifdef CONFIG_IPC_NS | |
7721 | perf_fill_ns_link_info(&ns_link_info[IPC_NS_INDEX], | |
7722 | task, &ipcns_operations); | |
7723 | #endif | |
7724 | #ifdef CONFIG_PID_NS | |
7725 | perf_fill_ns_link_info(&ns_link_info[PID_NS_INDEX], | |
7726 | task, &pidns_operations); | |
7727 | #endif | |
7728 | #ifdef CONFIG_CGROUPS | |
7729 | perf_fill_ns_link_info(&ns_link_info[CGROUP_NS_INDEX], | |
7730 | task, &cgroupns_operations); | |
7731 | #endif | |
7732 | ||
7733 | perf_iterate_sb(perf_event_namespaces_output, | |
7734 | &namespaces_event, | |
7735 | NULL); | |
7736 | } | |
7737 | ||
0a4a9391 PZ |
7738 | /* |
7739 | * mmap tracking | |
7740 | */ | |
7741 | ||
7742 | struct perf_mmap_event { | |
089dd79d PZ |
7743 | struct vm_area_struct *vma; |
7744 | ||
7745 | const char *file_name; | |
7746 | int file_size; | |
13d7a241 SE |
7747 | int maj, min; |
7748 | u64 ino; | |
7749 | u64 ino_generation; | |
f972eb63 | 7750 | u32 prot, flags; |
0a4a9391 PZ |
7751 | |
7752 | struct { | |
7753 | struct perf_event_header header; | |
7754 | ||
7755 | u32 pid; | |
7756 | u32 tid; | |
7757 | u64 start; | |
7758 | u64 len; | |
7759 | u64 pgoff; | |
cdd6c482 | 7760 | } event_id; |
0a4a9391 PZ |
7761 | }; |
7762 | ||
67516844 JO |
7763 | static int perf_event_mmap_match(struct perf_event *event, |
7764 | void *data) | |
7765 | { | |
7766 | struct perf_mmap_event *mmap_event = data; | |
7767 | struct vm_area_struct *vma = mmap_event->vma; | |
7768 | int executable = vma->vm_flags & VM_EXEC; | |
7769 | ||
7770 | return (!executable && event->attr.mmap_data) || | |
13d7a241 | 7771 | (executable && (event->attr.mmap || event->attr.mmap2)); |
67516844 JO |
7772 | } |
7773 | ||
cdd6c482 | 7774 | static void perf_event_mmap_output(struct perf_event *event, |
52d857a8 | 7775 | void *data) |
0a4a9391 | 7776 | { |
52d857a8 | 7777 | struct perf_mmap_event *mmap_event = data; |
0a4a9391 | 7778 | struct perf_output_handle handle; |
c980d109 | 7779 | struct perf_sample_data sample; |
cdd6c482 | 7780 | int size = mmap_event->event_id.header.size; |
d9c1bb2f | 7781 | u32 type = mmap_event->event_id.header.type; |
c980d109 | 7782 | int ret; |
0a4a9391 | 7783 | |
67516844 JO |
7784 | if (!perf_event_mmap_match(event, data)) |
7785 | return; | |
7786 | ||
13d7a241 SE |
7787 | if (event->attr.mmap2) { |
7788 | mmap_event->event_id.header.type = PERF_RECORD_MMAP2; | |
7789 | mmap_event->event_id.header.size += sizeof(mmap_event->maj); | |
7790 | mmap_event->event_id.header.size += sizeof(mmap_event->min); | |
7791 | mmap_event->event_id.header.size += sizeof(mmap_event->ino); | |
d008d525 | 7792 | mmap_event->event_id.header.size += sizeof(mmap_event->ino_generation); |
f972eb63 PZ |
7793 | mmap_event->event_id.header.size += sizeof(mmap_event->prot); |
7794 | mmap_event->event_id.header.size += sizeof(mmap_event->flags); | |
13d7a241 SE |
7795 | } |
7796 | ||
c980d109 ACM |
7797 | perf_event_header__init_id(&mmap_event->event_id.header, &sample, event); |
7798 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 7799 | mmap_event->event_id.header.size); |
0a4a9391 | 7800 | if (ret) |
c980d109 | 7801 | goto out; |
0a4a9391 | 7802 | |
cdd6c482 IM |
7803 | mmap_event->event_id.pid = perf_event_pid(event, current); |
7804 | mmap_event->event_id.tid = perf_event_tid(event, current); | |
709e50cf | 7805 | |
cdd6c482 | 7806 | perf_output_put(&handle, mmap_event->event_id); |
13d7a241 SE |
7807 | |
7808 | if (event->attr.mmap2) { | |
7809 | perf_output_put(&handle, mmap_event->maj); | |
7810 | perf_output_put(&handle, mmap_event->min); | |
7811 | perf_output_put(&handle, mmap_event->ino); | |
7812 | perf_output_put(&handle, mmap_event->ino_generation); | |
f972eb63 PZ |
7813 | perf_output_put(&handle, mmap_event->prot); |
7814 | perf_output_put(&handle, mmap_event->flags); | |
13d7a241 SE |
7815 | } |
7816 | ||
76369139 | 7817 | __output_copy(&handle, mmap_event->file_name, |
0a4a9391 | 7818 | mmap_event->file_size); |
c980d109 ACM |
7819 | |
7820 | perf_event__output_id_sample(event, &handle, &sample); | |
7821 | ||
78d613eb | 7822 | perf_output_end(&handle); |
c980d109 ACM |
7823 | out: |
7824 | mmap_event->event_id.header.size = size; | |
d9c1bb2f | 7825 | mmap_event->event_id.header.type = type; |
0a4a9391 PZ |
7826 | } |
7827 | ||
cdd6c482 | 7828 | static void perf_event_mmap_event(struct perf_mmap_event *mmap_event) |
0a4a9391 | 7829 | { |
089dd79d PZ |
7830 | struct vm_area_struct *vma = mmap_event->vma; |
7831 | struct file *file = vma->vm_file; | |
13d7a241 SE |
7832 | int maj = 0, min = 0; |
7833 | u64 ino = 0, gen = 0; | |
f972eb63 | 7834 | u32 prot = 0, flags = 0; |
0a4a9391 PZ |
7835 | unsigned int size; |
7836 | char tmp[16]; | |
7837 | char *buf = NULL; | |
2c42cfbf | 7838 | char *name; |
413ee3b4 | 7839 | |
0b3589be PZ |
7840 | if (vma->vm_flags & VM_READ) |
7841 | prot |= PROT_READ; | |
7842 | if (vma->vm_flags & VM_WRITE) | |
7843 | prot |= PROT_WRITE; | |
7844 | if (vma->vm_flags & VM_EXEC) | |
7845 | prot |= PROT_EXEC; | |
7846 | ||
7847 | if (vma->vm_flags & VM_MAYSHARE) | |
7848 | flags = MAP_SHARED; | |
7849 | else | |
7850 | flags = MAP_PRIVATE; | |
7851 | ||
7852 | if (vma->vm_flags & VM_DENYWRITE) | |
7853 | flags |= MAP_DENYWRITE; | |
7854 | if (vma->vm_flags & VM_MAYEXEC) | |
7855 | flags |= MAP_EXECUTABLE; | |
7856 | if (vma->vm_flags & VM_LOCKED) | |
7857 | flags |= MAP_LOCKED; | |
7858 | if (vma->vm_flags & VM_HUGETLB) | |
7859 | flags |= MAP_HUGETLB; | |
7860 | ||
0a4a9391 | 7861 | if (file) { |
13d7a241 SE |
7862 | struct inode *inode; |
7863 | dev_t dev; | |
3ea2f2b9 | 7864 | |
2c42cfbf | 7865 | buf = kmalloc(PATH_MAX, GFP_KERNEL); |
0a4a9391 | 7866 | if (!buf) { |
c7e548b4 ON |
7867 | name = "//enomem"; |
7868 | goto cpy_name; | |
0a4a9391 | 7869 | } |
413ee3b4 | 7870 | /* |
3ea2f2b9 | 7871 | * d_path() works from the end of the rb backwards, so we |
413ee3b4 AB |
7872 | * need to add enough zero bytes after the string to handle |
7873 | * the 64bit alignment we do later. | |
7874 | */ | |
9bf39ab2 | 7875 | name = file_path(file, buf, PATH_MAX - sizeof(u64)); |
0a4a9391 | 7876 | if (IS_ERR(name)) { |
c7e548b4 ON |
7877 | name = "//toolong"; |
7878 | goto cpy_name; | |
0a4a9391 | 7879 | } |
13d7a241 SE |
7880 | inode = file_inode(vma->vm_file); |
7881 | dev = inode->i_sb->s_dev; | |
7882 | ino = inode->i_ino; | |
7883 | gen = inode->i_generation; | |
7884 | maj = MAJOR(dev); | |
7885 | min = MINOR(dev); | |
f972eb63 | 7886 | |
c7e548b4 | 7887 | goto got_name; |
0a4a9391 | 7888 | } else { |
fbe26abe JO |
7889 | if (vma->vm_ops && vma->vm_ops->name) { |
7890 | name = (char *) vma->vm_ops->name(vma); | |
7891 | if (name) | |
7892 | goto cpy_name; | |
7893 | } | |
7894 | ||
2c42cfbf | 7895 | name = (char *)arch_vma_name(vma); |
c7e548b4 ON |
7896 | if (name) |
7897 | goto cpy_name; | |
089dd79d | 7898 | |
32c5fb7e | 7899 | if (vma->vm_start <= vma->vm_mm->start_brk && |
3af9e859 | 7900 | vma->vm_end >= vma->vm_mm->brk) { |
c7e548b4 ON |
7901 | name = "[heap]"; |
7902 | goto cpy_name; | |
32c5fb7e ON |
7903 | } |
7904 | if (vma->vm_start <= vma->vm_mm->start_stack && | |
3af9e859 | 7905 | vma->vm_end >= vma->vm_mm->start_stack) { |
c7e548b4 ON |
7906 | name = "[stack]"; |
7907 | goto cpy_name; | |
089dd79d PZ |
7908 | } |
7909 | ||
c7e548b4 ON |
7910 | name = "//anon"; |
7911 | goto cpy_name; | |
0a4a9391 PZ |
7912 | } |
7913 | ||
c7e548b4 ON |
7914 | cpy_name: |
7915 | strlcpy(tmp, name, sizeof(tmp)); | |
7916 | name = tmp; | |
0a4a9391 | 7917 | got_name: |
2c42cfbf PZ |
7918 | /* |
7919 | * Since our buffer works in 8 byte units we need to align our string | |
7920 | * size to a multiple of 8. However, we must guarantee the tail end is | |
7921 | * zero'd out to avoid leaking random bits to userspace. | |
7922 | */ | |
7923 | size = strlen(name)+1; | |
7924 | while (!IS_ALIGNED(size, sizeof(u64))) | |
7925 | name[size++] = '\0'; | |
0a4a9391 PZ |
7926 | |
7927 | mmap_event->file_name = name; | |
7928 | mmap_event->file_size = size; | |
13d7a241 SE |
7929 | mmap_event->maj = maj; |
7930 | mmap_event->min = min; | |
7931 | mmap_event->ino = ino; | |
7932 | mmap_event->ino_generation = gen; | |
f972eb63 PZ |
7933 | mmap_event->prot = prot; |
7934 | mmap_event->flags = flags; | |
0a4a9391 | 7935 | |
2fe85427 SE |
7936 | if (!(vma->vm_flags & VM_EXEC)) |
7937 | mmap_event->event_id.header.misc |= PERF_RECORD_MISC_MMAP_DATA; | |
7938 | ||
cdd6c482 | 7939 | mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size; |
0a4a9391 | 7940 | |
aab5b71e | 7941 | perf_iterate_sb(perf_event_mmap_output, |
52d857a8 JO |
7942 | mmap_event, |
7943 | NULL); | |
665c2142 | 7944 | |
0a4a9391 PZ |
7945 | kfree(buf); |
7946 | } | |
7947 | ||
375637bc AS |
7948 | /* |
7949 | * Check whether inode and address range match filter criteria. | |
7950 | */ | |
7951 | static bool perf_addr_filter_match(struct perf_addr_filter *filter, | |
7952 | struct file *file, unsigned long offset, | |
7953 | unsigned long size) | |
7954 | { | |
7f635ff1 MP |
7955 | /* d_inode(NULL) won't be equal to any mapped user-space file */ |
7956 | if (!filter->path.dentry) | |
7957 | return false; | |
7958 | ||
9511bce9 | 7959 | if (d_inode(filter->path.dentry) != file_inode(file)) |
375637bc AS |
7960 | return false; |
7961 | ||
7962 | if (filter->offset > offset + size) | |
7963 | return false; | |
7964 | ||
7965 | if (filter->offset + filter->size < offset) | |
7966 | return false; | |
7967 | ||
7968 | return true; | |
7969 | } | |
7970 | ||
c60f83b8 AS |
7971 | static bool perf_addr_filter_vma_adjust(struct perf_addr_filter *filter, |
7972 | struct vm_area_struct *vma, | |
7973 | struct perf_addr_filter_range *fr) | |
7974 | { | |
7975 | unsigned long vma_size = vma->vm_end - vma->vm_start; | |
7976 | unsigned long off = vma->vm_pgoff << PAGE_SHIFT; | |
7977 | struct file *file = vma->vm_file; | |
7978 | ||
7979 | if (!perf_addr_filter_match(filter, file, off, vma_size)) | |
7980 | return false; | |
7981 | ||
7982 | if (filter->offset < off) { | |
7983 | fr->start = vma->vm_start; | |
7984 | fr->size = min(vma_size, filter->size - (off - filter->offset)); | |
7985 | } else { | |
7986 | fr->start = vma->vm_start + filter->offset - off; | |
7987 | fr->size = min(vma->vm_end - fr->start, filter->size); | |
7988 | } | |
7989 | ||
7990 | return true; | |
7991 | } | |
7992 | ||
375637bc AS |
7993 | static void __perf_addr_filters_adjust(struct perf_event *event, void *data) |
7994 | { | |
7995 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
7996 | struct vm_area_struct *vma = data; | |
375637bc AS |
7997 | struct perf_addr_filter *filter; |
7998 | unsigned int restart = 0, count = 0; | |
c60f83b8 | 7999 | unsigned long flags; |
375637bc AS |
8000 | |
8001 | if (!has_addr_filter(event)) | |
8002 | return; | |
8003 | ||
c60f83b8 | 8004 | if (!vma->vm_file) |
375637bc AS |
8005 | return; |
8006 | ||
8007 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
8008 | list_for_each_entry(filter, &ifh->list, entry) { | |
c60f83b8 AS |
8009 | if (perf_addr_filter_vma_adjust(filter, vma, |
8010 | &event->addr_filter_ranges[count])) | |
375637bc | 8011 | restart++; |
375637bc AS |
8012 | |
8013 | count++; | |
8014 | } | |
8015 | ||
8016 | if (restart) | |
8017 | event->addr_filters_gen++; | |
8018 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
8019 | ||
8020 | if (restart) | |
767ae086 | 8021 | perf_event_stop(event, 1); |
375637bc AS |
8022 | } |
8023 | ||
8024 | /* | |
8025 | * Adjust all task's events' filters to the new vma | |
8026 | */ | |
8027 | static void perf_addr_filters_adjust(struct vm_area_struct *vma) | |
8028 | { | |
8029 | struct perf_event_context *ctx; | |
8030 | int ctxn; | |
8031 | ||
12b40a23 MP |
8032 | /* |
8033 | * Data tracing isn't supported yet and as such there is no need | |
8034 | * to keep track of anything that isn't related to executable code: | |
8035 | */ | |
8036 | if (!(vma->vm_flags & VM_EXEC)) | |
8037 | return; | |
8038 | ||
375637bc AS |
8039 | rcu_read_lock(); |
8040 | for_each_task_context_nr(ctxn) { | |
8041 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); | |
8042 | if (!ctx) | |
8043 | continue; | |
8044 | ||
aab5b71e | 8045 | perf_iterate_ctx(ctx, __perf_addr_filters_adjust, vma, true); |
375637bc AS |
8046 | } |
8047 | rcu_read_unlock(); | |
8048 | } | |
8049 | ||
3af9e859 | 8050 | void perf_event_mmap(struct vm_area_struct *vma) |
0a4a9391 | 8051 | { |
9ee318a7 PZ |
8052 | struct perf_mmap_event mmap_event; |
8053 | ||
cdd6c482 | 8054 | if (!atomic_read(&nr_mmap_events)) |
9ee318a7 PZ |
8055 | return; |
8056 | ||
8057 | mmap_event = (struct perf_mmap_event){ | |
089dd79d | 8058 | .vma = vma, |
573402db PZ |
8059 | /* .file_name */ |
8060 | /* .file_size */ | |
cdd6c482 | 8061 | .event_id = { |
573402db | 8062 | .header = { |
cdd6c482 | 8063 | .type = PERF_RECORD_MMAP, |
39447b38 | 8064 | .misc = PERF_RECORD_MISC_USER, |
573402db PZ |
8065 | /* .size */ |
8066 | }, | |
8067 | /* .pid */ | |
8068 | /* .tid */ | |
089dd79d PZ |
8069 | .start = vma->vm_start, |
8070 | .len = vma->vm_end - vma->vm_start, | |
3a0304e9 | 8071 | .pgoff = (u64)vma->vm_pgoff << PAGE_SHIFT, |
0a4a9391 | 8072 | }, |
13d7a241 SE |
8073 | /* .maj (attr_mmap2 only) */ |
8074 | /* .min (attr_mmap2 only) */ | |
8075 | /* .ino (attr_mmap2 only) */ | |
8076 | /* .ino_generation (attr_mmap2 only) */ | |
f972eb63 PZ |
8077 | /* .prot (attr_mmap2 only) */ |
8078 | /* .flags (attr_mmap2 only) */ | |
0a4a9391 PZ |
8079 | }; |
8080 | ||
375637bc | 8081 | perf_addr_filters_adjust(vma); |
cdd6c482 | 8082 | perf_event_mmap_event(&mmap_event); |
0a4a9391 PZ |
8083 | } |
8084 | ||
68db7e98 AS |
8085 | void perf_event_aux_event(struct perf_event *event, unsigned long head, |
8086 | unsigned long size, u64 flags) | |
8087 | { | |
8088 | struct perf_output_handle handle; | |
8089 | struct perf_sample_data sample; | |
8090 | struct perf_aux_event { | |
8091 | struct perf_event_header header; | |
8092 | u64 offset; | |
8093 | u64 size; | |
8094 | u64 flags; | |
8095 | } rec = { | |
8096 | .header = { | |
8097 | .type = PERF_RECORD_AUX, | |
8098 | .misc = 0, | |
8099 | .size = sizeof(rec), | |
8100 | }, | |
8101 | .offset = head, | |
8102 | .size = size, | |
8103 | .flags = flags, | |
8104 | }; | |
8105 | int ret; | |
8106 | ||
8107 | perf_event_header__init_id(&rec.header, &sample, event); | |
8108 | ret = perf_output_begin(&handle, event, rec.header.size); | |
8109 | ||
8110 | if (ret) | |
8111 | return; | |
8112 | ||
8113 | perf_output_put(&handle, rec); | |
8114 | perf_event__output_id_sample(event, &handle, &sample); | |
8115 | ||
8116 | perf_output_end(&handle); | |
8117 | } | |
8118 | ||
f38b0dbb KL |
8119 | /* |
8120 | * Lost/dropped samples logging | |
8121 | */ | |
8122 | void perf_log_lost_samples(struct perf_event *event, u64 lost) | |
8123 | { | |
8124 | struct perf_output_handle handle; | |
8125 | struct perf_sample_data sample; | |
8126 | int ret; | |
8127 | ||
8128 | struct { | |
8129 | struct perf_event_header header; | |
8130 | u64 lost; | |
8131 | } lost_samples_event = { | |
8132 | .header = { | |
8133 | .type = PERF_RECORD_LOST_SAMPLES, | |
8134 | .misc = 0, | |
8135 | .size = sizeof(lost_samples_event), | |
8136 | }, | |
8137 | .lost = lost, | |
8138 | }; | |
8139 | ||
8140 | perf_event_header__init_id(&lost_samples_event.header, &sample, event); | |
8141 | ||
8142 | ret = perf_output_begin(&handle, event, | |
8143 | lost_samples_event.header.size); | |
8144 | if (ret) | |
8145 | return; | |
8146 | ||
8147 | perf_output_put(&handle, lost_samples_event); | |
8148 | perf_event__output_id_sample(event, &handle, &sample); | |
8149 | perf_output_end(&handle); | |
8150 | } | |
8151 | ||
45ac1403 AH |
8152 | /* |
8153 | * context_switch tracking | |
8154 | */ | |
8155 | ||
8156 | struct perf_switch_event { | |
8157 | struct task_struct *task; | |
8158 | struct task_struct *next_prev; | |
8159 | ||
8160 | struct { | |
8161 | struct perf_event_header header; | |
8162 | u32 next_prev_pid; | |
8163 | u32 next_prev_tid; | |
8164 | } event_id; | |
8165 | }; | |
8166 | ||
8167 | static int perf_event_switch_match(struct perf_event *event) | |
8168 | { | |
8169 | return event->attr.context_switch; | |
8170 | } | |
8171 | ||
8172 | static void perf_event_switch_output(struct perf_event *event, void *data) | |
8173 | { | |
8174 | struct perf_switch_event *se = data; | |
8175 | struct perf_output_handle handle; | |
8176 | struct perf_sample_data sample; | |
8177 | int ret; | |
8178 | ||
8179 | if (!perf_event_switch_match(event)) | |
8180 | return; | |
8181 | ||
8182 | /* Only CPU-wide events are allowed to see next/prev pid/tid */ | |
8183 | if (event->ctx->task) { | |
8184 | se->event_id.header.type = PERF_RECORD_SWITCH; | |
8185 | se->event_id.header.size = sizeof(se->event_id.header); | |
8186 | } else { | |
8187 | se->event_id.header.type = PERF_RECORD_SWITCH_CPU_WIDE; | |
8188 | se->event_id.header.size = sizeof(se->event_id); | |
8189 | se->event_id.next_prev_pid = | |
8190 | perf_event_pid(event, se->next_prev); | |
8191 | se->event_id.next_prev_tid = | |
8192 | perf_event_tid(event, se->next_prev); | |
8193 | } | |
8194 | ||
8195 | perf_event_header__init_id(&se->event_id.header, &sample, event); | |
8196 | ||
8197 | ret = perf_output_begin(&handle, event, se->event_id.header.size); | |
8198 | if (ret) | |
8199 | return; | |
8200 | ||
8201 | if (event->ctx->task) | |
8202 | perf_output_put(&handle, se->event_id.header); | |
8203 | else | |
8204 | perf_output_put(&handle, se->event_id); | |
8205 | ||
8206 | perf_event__output_id_sample(event, &handle, &sample); | |
8207 | ||
8208 | perf_output_end(&handle); | |
8209 | } | |
8210 | ||
8211 | static void perf_event_switch(struct task_struct *task, | |
8212 | struct task_struct *next_prev, bool sched_in) | |
8213 | { | |
8214 | struct perf_switch_event switch_event; | |
8215 | ||
8216 | /* N.B. caller checks nr_switch_events != 0 */ | |
8217 | ||
8218 | switch_event = (struct perf_switch_event){ | |
8219 | .task = task, | |
8220 | .next_prev = next_prev, | |
8221 | .event_id = { | |
8222 | .header = { | |
8223 | /* .type */ | |
8224 | .misc = sched_in ? 0 : PERF_RECORD_MISC_SWITCH_OUT, | |
8225 | /* .size */ | |
8226 | }, | |
8227 | /* .next_prev_pid */ | |
8228 | /* .next_prev_tid */ | |
8229 | }, | |
8230 | }; | |
8231 | ||
101592b4 AB |
8232 | if (!sched_in && task->state == TASK_RUNNING) |
8233 | switch_event.event_id.header.misc |= | |
8234 | PERF_RECORD_MISC_SWITCH_OUT_PREEMPT; | |
8235 | ||
aab5b71e | 8236 | perf_iterate_sb(perf_event_switch_output, |
45ac1403 AH |
8237 | &switch_event, |
8238 | NULL); | |
8239 | } | |
8240 | ||
a78ac325 PZ |
8241 | /* |
8242 | * IRQ throttle logging | |
8243 | */ | |
8244 | ||
cdd6c482 | 8245 | static void perf_log_throttle(struct perf_event *event, int enable) |
a78ac325 PZ |
8246 | { |
8247 | struct perf_output_handle handle; | |
c980d109 | 8248 | struct perf_sample_data sample; |
a78ac325 PZ |
8249 | int ret; |
8250 | ||
8251 | struct { | |
8252 | struct perf_event_header header; | |
8253 | u64 time; | |
cca3f454 | 8254 | u64 id; |
7f453c24 | 8255 | u64 stream_id; |
a78ac325 PZ |
8256 | } throttle_event = { |
8257 | .header = { | |
cdd6c482 | 8258 | .type = PERF_RECORD_THROTTLE, |
a78ac325 PZ |
8259 | .misc = 0, |
8260 | .size = sizeof(throttle_event), | |
8261 | }, | |
34f43927 | 8262 | .time = perf_event_clock(event), |
cdd6c482 IM |
8263 | .id = primary_event_id(event), |
8264 | .stream_id = event->id, | |
a78ac325 PZ |
8265 | }; |
8266 | ||
966ee4d6 | 8267 | if (enable) |
cdd6c482 | 8268 | throttle_event.header.type = PERF_RECORD_UNTHROTTLE; |
966ee4d6 | 8269 | |
c980d109 ACM |
8270 | perf_event_header__init_id(&throttle_event.header, &sample, event); |
8271 | ||
8272 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 8273 | throttle_event.header.size); |
a78ac325 PZ |
8274 | if (ret) |
8275 | return; | |
8276 | ||
8277 | perf_output_put(&handle, throttle_event); | |
c980d109 | 8278 | perf_event__output_id_sample(event, &handle, &sample); |
a78ac325 PZ |
8279 | perf_output_end(&handle); |
8280 | } | |
8281 | ||
76193a94 SL |
8282 | /* |
8283 | * ksymbol register/unregister tracking | |
8284 | */ | |
8285 | ||
8286 | struct perf_ksymbol_event { | |
8287 | const char *name; | |
8288 | int name_len; | |
8289 | struct { | |
8290 | struct perf_event_header header; | |
8291 | u64 addr; | |
8292 | u32 len; | |
8293 | u16 ksym_type; | |
8294 | u16 flags; | |
8295 | } event_id; | |
8296 | }; | |
8297 | ||
8298 | static int perf_event_ksymbol_match(struct perf_event *event) | |
8299 | { | |
8300 | return event->attr.ksymbol; | |
8301 | } | |
8302 | ||
8303 | static void perf_event_ksymbol_output(struct perf_event *event, void *data) | |
8304 | { | |
8305 | struct perf_ksymbol_event *ksymbol_event = data; | |
8306 | struct perf_output_handle handle; | |
8307 | struct perf_sample_data sample; | |
8308 | int ret; | |
8309 | ||
8310 | if (!perf_event_ksymbol_match(event)) | |
8311 | return; | |
8312 | ||
8313 | perf_event_header__init_id(&ksymbol_event->event_id.header, | |
8314 | &sample, event); | |
8315 | ret = perf_output_begin(&handle, event, | |
8316 | ksymbol_event->event_id.header.size); | |
8317 | if (ret) | |
8318 | return; | |
8319 | ||
8320 | perf_output_put(&handle, ksymbol_event->event_id); | |
8321 | __output_copy(&handle, ksymbol_event->name, ksymbol_event->name_len); | |
8322 | perf_event__output_id_sample(event, &handle, &sample); | |
8323 | ||
8324 | perf_output_end(&handle); | |
8325 | } | |
8326 | ||
8327 | void perf_event_ksymbol(u16 ksym_type, u64 addr, u32 len, bool unregister, | |
8328 | const char *sym) | |
8329 | { | |
8330 | struct perf_ksymbol_event ksymbol_event; | |
8331 | char name[KSYM_NAME_LEN]; | |
8332 | u16 flags = 0; | |
8333 | int name_len; | |
8334 | ||
8335 | if (!atomic_read(&nr_ksymbol_events)) | |
8336 | return; | |
8337 | ||
8338 | if (ksym_type >= PERF_RECORD_KSYMBOL_TYPE_MAX || | |
8339 | ksym_type == PERF_RECORD_KSYMBOL_TYPE_UNKNOWN) | |
8340 | goto err; | |
8341 | ||
8342 | strlcpy(name, sym, KSYM_NAME_LEN); | |
8343 | name_len = strlen(name) + 1; | |
8344 | while (!IS_ALIGNED(name_len, sizeof(u64))) | |
8345 | name[name_len++] = '\0'; | |
8346 | BUILD_BUG_ON(KSYM_NAME_LEN % sizeof(u64)); | |
8347 | ||
8348 | if (unregister) | |
8349 | flags |= PERF_RECORD_KSYMBOL_FLAGS_UNREGISTER; | |
8350 | ||
8351 | ksymbol_event = (struct perf_ksymbol_event){ | |
8352 | .name = name, | |
8353 | .name_len = name_len, | |
8354 | .event_id = { | |
8355 | .header = { | |
8356 | .type = PERF_RECORD_KSYMBOL, | |
8357 | .size = sizeof(ksymbol_event.event_id) + | |
8358 | name_len, | |
8359 | }, | |
8360 | .addr = addr, | |
8361 | .len = len, | |
8362 | .ksym_type = ksym_type, | |
8363 | .flags = flags, | |
8364 | }, | |
8365 | }; | |
8366 | ||
8367 | perf_iterate_sb(perf_event_ksymbol_output, &ksymbol_event, NULL); | |
8368 | return; | |
8369 | err: | |
8370 | WARN_ONCE(1, "%s: Invalid KSYMBOL type 0x%x\n", __func__, ksym_type); | |
8371 | } | |
8372 | ||
6ee52e2a SL |
8373 | /* |
8374 | * bpf program load/unload tracking | |
8375 | */ | |
8376 | ||
8377 | struct perf_bpf_event { | |
8378 | struct bpf_prog *prog; | |
8379 | struct { | |
8380 | struct perf_event_header header; | |
8381 | u16 type; | |
8382 | u16 flags; | |
8383 | u32 id; | |
8384 | u8 tag[BPF_TAG_SIZE]; | |
8385 | } event_id; | |
8386 | }; | |
8387 | ||
8388 | static int perf_event_bpf_match(struct perf_event *event) | |
8389 | { | |
8390 | return event->attr.bpf_event; | |
8391 | } | |
8392 | ||
8393 | static void perf_event_bpf_output(struct perf_event *event, void *data) | |
8394 | { | |
8395 | struct perf_bpf_event *bpf_event = data; | |
8396 | struct perf_output_handle handle; | |
8397 | struct perf_sample_data sample; | |
8398 | int ret; | |
8399 | ||
8400 | if (!perf_event_bpf_match(event)) | |
8401 | return; | |
8402 | ||
8403 | perf_event_header__init_id(&bpf_event->event_id.header, | |
8404 | &sample, event); | |
8405 | ret = perf_output_begin(&handle, event, | |
8406 | bpf_event->event_id.header.size); | |
8407 | if (ret) | |
8408 | return; | |
8409 | ||
8410 | perf_output_put(&handle, bpf_event->event_id); | |
8411 | perf_event__output_id_sample(event, &handle, &sample); | |
8412 | ||
8413 | perf_output_end(&handle); | |
8414 | } | |
8415 | ||
8416 | static void perf_event_bpf_emit_ksymbols(struct bpf_prog *prog, | |
8417 | enum perf_bpf_event_type type) | |
8418 | { | |
8419 | bool unregister = type == PERF_BPF_EVENT_PROG_UNLOAD; | |
8420 | char sym[KSYM_NAME_LEN]; | |
8421 | int i; | |
8422 | ||
8423 | if (prog->aux->func_cnt == 0) { | |
8424 | bpf_get_prog_name(prog, sym); | |
8425 | perf_event_ksymbol(PERF_RECORD_KSYMBOL_TYPE_BPF, | |
8426 | (u64)(unsigned long)prog->bpf_func, | |
8427 | prog->jited_len, unregister, sym); | |
8428 | } else { | |
8429 | for (i = 0; i < prog->aux->func_cnt; i++) { | |
8430 | struct bpf_prog *subprog = prog->aux->func[i]; | |
8431 | ||
8432 | bpf_get_prog_name(subprog, sym); | |
8433 | perf_event_ksymbol( | |
8434 | PERF_RECORD_KSYMBOL_TYPE_BPF, | |
8435 | (u64)(unsigned long)subprog->bpf_func, | |
8436 | subprog->jited_len, unregister, sym); | |
8437 | } | |
8438 | } | |
8439 | } | |
8440 | ||
8441 | void perf_event_bpf_event(struct bpf_prog *prog, | |
8442 | enum perf_bpf_event_type type, | |
8443 | u16 flags) | |
8444 | { | |
8445 | struct perf_bpf_event bpf_event; | |
8446 | ||
8447 | if (type <= PERF_BPF_EVENT_UNKNOWN || | |
8448 | type >= PERF_BPF_EVENT_MAX) | |
8449 | return; | |
8450 | ||
8451 | switch (type) { | |
8452 | case PERF_BPF_EVENT_PROG_LOAD: | |
8453 | case PERF_BPF_EVENT_PROG_UNLOAD: | |
8454 | if (atomic_read(&nr_ksymbol_events)) | |
8455 | perf_event_bpf_emit_ksymbols(prog, type); | |
8456 | break; | |
8457 | default: | |
8458 | break; | |
8459 | } | |
8460 | ||
8461 | if (!atomic_read(&nr_bpf_events)) | |
8462 | return; | |
8463 | ||
8464 | bpf_event = (struct perf_bpf_event){ | |
8465 | .prog = prog, | |
8466 | .event_id = { | |
8467 | .header = { | |
8468 | .type = PERF_RECORD_BPF_EVENT, | |
8469 | .size = sizeof(bpf_event.event_id), | |
8470 | }, | |
8471 | .type = type, | |
8472 | .flags = flags, | |
8473 | .id = prog->aux->id, | |
8474 | }, | |
8475 | }; | |
8476 | ||
8477 | BUILD_BUG_ON(BPF_TAG_SIZE % sizeof(u64)); | |
8478 | ||
8479 | memcpy(bpf_event.event_id.tag, prog->tag, BPF_TAG_SIZE); | |
8480 | perf_iterate_sb(perf_event_bpf_output, &bpf_event, NULL); | |
8481 | } | |
8482 | ||
8d4e6c4c AS |
8483 | void perf_event_itrace_started(struct perf_event *event) |
8484 | { | |
8485 | event->attach_state |= PERF_ATTACH_ITRACE; | |
8486 | } | |
8487 | ||
ec0d7729 AS |
8488 | static void perf_log_itrace_start(struct perf_event *event) |
8489 | { | |
8490 | struct perf_output_handle handle; | |
8491 | struct perf_sample_data sample; | |
8492 | struct perf_aux_event { | |
8493 | struct perf_event_header header; | |
8494 | u32 pid; | |
8495 | u32 tid; | |
8496 | } rec; | |
8497 | int ret; | |
8498 | ||
8499 | if (event->parent) | |
8500 | event = event->parent; | |
8501 | ||
8502 | if (!(event->pmu->capabilities & PERF_PMU_CAP_ITRACE) || | |
8d4e6c4c | 8503 | event->attach_state & PERF_ATTACH_ITRACE) |
ec0d7729 AS |
8504 | return; |
8505 | ||
ec0d7729 AS |
8506 | rec.header.type = PERF_RECORD_ITRACE_START; |
8507 | rec.header.misc = 0; | |
8508 | rec.header.size = sizeof(rec); | |
8509 | rec.pid = perf_event_pid(event, current); | |
8510 | rec.tid = perf_event_tid(event, current); | |
8511 | ||
8512 | perf_event_header__init_id(&rec.header, &sample, event); | |
8513 | ret = perf_output_begin(&handle, event, rec.header.size); | |
8514 | ||
8515 | if (ret) | |
8516 | return; | |
8517 | ||
8518 | perf_output_put(&handle, rec); | |
8519 | perf_event__output_id_sample(event, &handle, &sample); | |
8520 | ||
8521 | perf_output_end(&handle); | |
8522 | } | |
8523 | ||
475113d9 JO |
8524 | static int |
8525 | __perf_event_account_interrupt(struct perf_event *event, int throttle) | |
f6c7d5fe | 8526 | { |
cdd6c482 | 8527 | struct hw_perf_event *hwc = &event->hw; |
79f14641 | 8528 | int ret = 0; |
475113d9 | 8529 | u64 seq; |
96398826 | 8530 | |
e050e3f0 SE |
8531 | seq = __this_cpu_read(perf_throttled_seq); |
8532 | if (seq != hwc->interrupts_seq) { | |
8533 | hwc->interrupts_seq = seq; | |
8534 | hwc->interrupts = 1; | |
8535 | } else { | |
8536 | hwc->interrupts++; | |
8537 | if (unlikely(throttle | |
8538 | && hwc->interrupts >= max_samples_per_tick)) { | |
8539 | __this_cpu_inc(perf_throttled_count); | |
555e0c1e | 8540 | tick_dep_set_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
163ec435 PZ |
8541 | hwc->interrupts = MAX_INTERRUPTS; |
8542 | perf_log_throttle(event, 0); | |
a78ac325 PZ |
8543 | ret = 1; |
8544 | } | |
e050e3f0 | 8545 | } |
60db5e09 | 8546 | |
cdd6c482 | 8547 | if (event->attr.freq) { |
def0a9b2 | 8548 | u64 now = perf_clock(); |
abd50713 | 8549 | s64 delta = now - hwc->freq_time_stamp; |
bd2b5b12 | 8550 | |
abd50713 | 8551 | hwc->freq_time_stamp = now; |
bd2b5b12 | 8552 | |
abd50713 | 8553 | if (delta > 0 && delta < 2*TICK_NSEC) |
f39d47ff | 8554 | perf_adjust_period(event, delta, hwc->last_period, true); |
bd2b5b12 PZ |
8555 | } |
8556 | ||
475113d9 JO |
8557 | return ret; |
8558 | } | |
8559 | ||
8560 | int perf_event_account_interrupt(struct perf_event *event) | |
8561 | { | |
8562 | return __perf_event_account_interrupt(event, 1); | |
8563 | } | |
8564 | ||
8565 | /* | |
8566 | * Generic event overflow handling, sampling. | |
8567 | */ | |
8568 | ||
8569 | static int __perf_event_overflow(struct perf_event *event, | |
8570 | int throttle, struct perf_sample_data *data, | |
8571 | struct pt_regs *regs) | |
8572 | { | |
8573 | int events = atomic_read(&event->event_limit); | |
8574 | int ret = 0; | |
8575 | ||
8576 | /* | |
8577 | * Non-sampling counters might still use the PMI to fold short | |
8578 | * hardware counters, ignore those. | |
8579 | */ | |
8580 | if (unlikely(!is_sampling_event(event))) | |
8581 | return 0; | |
8582 | ||
8583 | ret = __perf_event_account_interrupt(event, throttle); | |
cc1582c2 | 8584 | |
2023b359 PZ |
8585 | /* |
8586 | * XXX event_limit might not quite work as expected on inherited | |
cdd6c482 | 8587 | * events |
2023b359 PZ |
8588 | */ |
8589 | ||
cdd6c482 IM |
8590 | event->pending_kill = POLL_IN; |
8591 | if (events && atomic_dec_and_test(&event->event_limit)) { | |
79f14641 | 8592 | ret = 1; |
cdd6c482 | 8593 | event->pending_kill = POLL_HUP; |
5aab90ce JO |
8594 | |
8595 | perf_event_disable_inatomic(event); | |
79f14641 PZ |
8596 | } |
8597 | ||
aa6a5f3c | 8598 | READ_ONCE(event->overflow_handler)(event, data, regs); |
453f19ee | 8599 | |
fed66e2c | 8600 | if (*perf_event_fasync(event) && event->pending_kill) { |
a8b0ca17 PZ |
8601 | event->pending_wakeup = 1; |
8602 | irq_work_queue(&event->pending); | |
f506b3dc PZ |
8603 | } |
8604 | ||
79f14641 | 8605 | return ret; |
f6c7d5fe PZ |
8606 | } |
8607 | ||
a8b0ca17 | 8608 | int perf_event_overflow(struct perf_event *event, |
5622f295 MM |
8609 | struct perf_sample_data *data, |
8610 | struct pt_regs *regs) | |
850bc73f | 8611 | { |
a8b0ca17 | 8612 | return __perf_event_overflow(event, 1, data, regs); |
850bc73f PZ |
8613 | } |
8614 | ||
15dbf27c | 8615 | /* |
cdd6c482 | 8616 | * Generic software event infrastructure |
15dbf27c PZ |
8617 | */ |
8618 | ||
b28ab83c PZ |
8619 | struct swevent_htable { |
8620 | struct swevent_hlist *swevent_hlist; | |
8621 | struct mutex hlist_mutex; | |
8622 | int hlist_refcount; | |
8623 | ||
8624 | /* Recursion avoidance in each contexts */ | |
8625 | int recursion[PERF_NR_CONTEXTS]; | |
8626 | }; | |
8627 | ||
8628 | static DEFINE_PER_CPU(struct swevent_htable, swevent_htable); | |
8629 | ||
7b4b6658 | 8630 | /* |
cdd6c482 IM |
8631 | * We directly increment event->count and keep a second value in |
8632 | * event->hw.period_left to count intervals. This period event | |
7b4b6658 PZ |
8633 | * is kept in the range [-sample_period, 0] so that we can use the |
8634 | * sign as trigger. | |
8635 | */ | |
8636 | ||
ab573844 | 8637 | u64 perf_swevent_set_period(struct perf_event *event) |
15dbf27c | 8638 | { |
cdd6c482 | 8639 | struct hw_perf_event *hwc = &event->hw; |
7b4b6658 PZ |
8640 | u64 period = hwc->last_period; |
8641 | u64 nr, offset; | |
8642 | s64 old, val; | |
8643 | ||
8644 | hwc->last_period = hwc->sample_period; | |
15dbf27c PZ |
8645 | |
8646 | again: | |
e7850595 | 8647 | old = val = local64_read(&hwc->period_left); |
7b4b6658 PZ |
8648 | if (val < 0) |
8649 | return 0; | |
15dbf27c | 8650 | |
7b4b6658 PZ |
8651 | nr = div64_u64(period + val, period); |
8652 | offset = nr * period; | |
8653 | val -= offset; | |
e7850595 | 8654 | if (local64_cmpxchg(&hwc->period_left, old, val) != old) |
7b4b6658 | 8655 | goto again; |
15dbf27c | 8656 | |
7b4b6658 | 8657 | return nr; |
15dbf27c PZ |
8658 | } |
8659 | ||
0cff784a | 8660 | static void perf_swevent_overflow(struct perf_event *event, u64 overflow, |
a8b0ca17 | 8661 | struct perf_sample_data *data, |
5622f295 | 8662 | struct pt_regs *regs) |
15dbf27c | 8663 | { |
cdd6c482 | 8664 | struct hw_perf_event *hwc = &event->hw; |
850bc73f | 8665 | int throttle = 0; |
15dbf27c | 8666 | |
0cff784a PZ |
8667 | if (!overflow) |
8668 | overflow = perf_swevent_set_period(event); | |
15dbf27c | 8669 | |
7b4b6658 PZ |
8670 | if (hwc->interrupts == MAX_INTERRUPTS) |
8671 | return; | |
15dbf27c | 8672 | |
7b4b6658 | 8673 | for (; overflow; overflow--) { |
a8b0ca17 | 8674 | if (__perf_event_overflow(event, throttle, |
5622f295 | 8675 | data, regs)) { |
7b4b6658 PZ |
8676 | /* |
8677 | * We inhibit the overflow from happening when | |
8678 | * hwc->interrupts == MAX_INTERRUPTS. | |
8679 | */ | |
8680 | break; | |
8681 | } | |
cf450a73 | 8682 | throttle = 1; |
7b4b6658 | 8683 | } |
15dbf27c PZ |
8684 | } |
8685 | ||
a4eaf7f1 | 8686 | static void perf_swevent_event(struct perf_event *event, u64 nr, |
a8b0ca17 | 8687 | struct perf_sample_data *data, |
5622f295 | 8688 | struct pt_regs *regs) |
7b4b6658 | 8689 | { |
cdd6c482 | 8690 | struct hw_perf_event *hwc = &event->hw; |
d6d020e9 | 8691 | |
e7850595 | 8692 | local64_add(nr, &event->count); |
d6d020e9 | 8693 | |
0cff784a PZ |
8694 | if (!regs) |
8695 | return; | |
8696 | ||
6c7e550f | 8697 | if (!is_sampling_event(event)) |
7b4b6658 | 8698 | return; |
d6d020e9 | 8699 | |
5d81e5cf AV |
8700 | if ((event->attr.sample_type & PERF_SAMPLE_PERIOD) && !event->attr.freq) { |
8701 | data->period = nr; | |
8702 | return perf_swevent_overflow(event, 1, data, regs); | |
8703 | } else | |
8704 | data->period = event->hw.last_period; | |
8705 | ||
0cff784a | 8706 | if (nr == 1 && hwc->sample_period == 1 && !event->attr.freq) |
a8b0ca17 | 8707 | return perf_swevent_overflow(event, 1, data, regs); |
0cff784a | 8708 | |
e7850595 | 8709 | if (local64_add_negative(nr, &hwc->period_left)) |
7b4b6658 | 8710 | return; |
df1a132b | 8711 | |
a8b0ca17 | 8712 | perf_swevent_overflow(event, 0, data, regs); |
d6d020e9 PZ |
8713 | } |
8714 | ||
f5ffe02e FW |
8715 | static int perf_exclude_event(struct perf_event *event, |
8716 | struct pt_regs *regs) | |
8717 | { | |
a4eaf7f1 | 8718 | if (event->hw.state & PERF_HES_STOPPED) |
91b2f482 | 8719 | return 1; |
a4eaf7f1 | 8720 | |
f5ffe02e FW |
8721 | if (regs) { |
8722 | if (event->attr.exclude_user && user_mode(regs)) | |
8723 | return 1; | |
8724 | ||
8725 | if (event->attr.exclude_kernel && !user_mode(regs)) | |
8726 | return 1; | |
8727 | } | |
8728 | ||
8729 | return 0; | |
8730 | } | |
8731 | ||
cdd6c482 | 8732 | static int perf_swevent_match(struct perf_event *event, |
1c432d89 | 8733 | enum perf_type_id type, |
6fb2915d LZ |
8734 | u32 event_id, |
8735 | struct perf_sample_data *data, | |
8736 | struct pt_regs *regs) | |
15dbf27c | 8737 | { |
cdd6c482 | 8738 | if (event->attr.type != type) |
a21ca2ca | 8739 | return 0; |
f5ffe02e | 8740 | |
cdd6c482 | 8741 | if (event->attr.config != event_id) |
15dbf27c PZ |
8742 | return 0; |
8743 | ||
f5ffe02e FW |
8744 | if (perf_exclude_event(event, regs)) |
8745 | return 0; | |
15dbf27c PZ |
8746 | |
8747 | return 1; | |
8748 | } | |
8749 | ||
76e1d904 FW |
8750 | static inline u64 swevent_hash(u64 type, u32 event_id) |
8751 | { | |
8752 | u64 val = event_id | (type << 32); | |
8753 | ||
8754 | return hash_64(val, SWEVENT_HLIST_BITS); | |
8755 | } | |
8756 | ||
49f135ed FW |
8757 | static inline struct hlist_head * |
8758 | __find_swevent_head(struct swevent_hlist *hlist, u64 type, u32 event_id) | |
76e1d904 | 8759 | { |
49f135ed FW |
8760 | u64 hash = swevent_hash(type, event_id); |
8761 | ||
8762 | return &hlist->heads[hash]; | |
8763 | } | |
76e1d904 | 8764 | |
49f135ed FW |
8765 | /* For the read side: events when they trigger */ |
8766 | static inline struct hlist_head * | |
b28ab83c | 8767 | find_swevent_head_rcu(struct swevent_htable *swhash, u64 type, u32 event_id) |
49f135ed FW |
8768 | { |
8769 | struct swevent_hlist *hlist; | |
76e1d904 | 8770 | |
b28ab83c | 8771 | hlist = rcu_dereference(swhash->swevent_hlist); |
76e1d904 FW |
8772 | if (!hlist) |
8773 | return NULL; | |
8774 | ||
49f135ed FW |
8775 | return __find_swevent_head(hlist, type, event_id); |
8776 | } | |
8777 | ||
8778 | /* For the event head insertion and removal in the hlist */ | |
8779 | static inline struct hlist_head * | |
b28ab83c | 8780 | find_swevent_head(struct swevent_htable *swhash, struct perf_event *event) |
49f135ed FW |
8781 | { |
8782 | struct swevent_hlist *hlist; | |
8783 | u32 event_id = event->attr.config; | |
8784 | u64 type = event->attr.type; | |
8785 | ||
8786 | /* | |
8787 | * Event scheduling is always serialized against hlist allocation | |
8788 | * and release. Which makes the protected version suitable here. | |
8789 | * The context lock guarantees that. | |
8790 | */ | |
b28ab83c | 8791 | hlist = rcu_dereference_protected(swhash->swevent_hlist, |
49f135ed FW |
8792 | lockdep_is_held(&event->ctx->lock)); |
8793 | if (!hlist) | |
8794 | return NULL; | |
8795 | ||
8796 | return __find_swevent_head(hlist, type, event_id); | |
76e1d904 FW |
8797 | } |
8798 | ||
8799 | static void do_perf_sw_event(enum perf_type_id type, u32 event_id, | |
a8b0ca17 | 8800 | u64 nr, |
76e1d904 FW |
8801 | struct perf_sample_data *data, |
8802 | struct pt_regs *regs) | |
15dbf27c | 8803 | { |
4a32fea9 | 8804 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 8805 | struct perf_event *event; |
76e1d904 | 8806 | struct hlist_head *head; |
15dbf27c | 8807 | |
76e1d904 | 8808 | rcu_read_lock(); |
b28ab83c | 8809 | head = find_swevent_head_rcu(swhash, type, event_id); |
76e1d904 FW |
8810 | if (!head) |
8811 | goto end; | |
8812 | ||
b67bfe0d | 8813 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
6fb2915d | 8814 | if (perf_swevent_match(event, type, event_id, data, regs)) |
a8b0ca17 | 8815 | perf_swevent_event(event, nr, data, regs); |
15dbf27c | 8816 | } |
76e1d904 FW |
8817 | end: |
8818 | rcu_read_unlock(); | |
15dbf27c PZ |
8819 | } |
8820 | ||
86038c5e PZI |
8821 | DEFINE_PER_CPU(struct pt_regs, __perf_regs[4]); |
8822 | ||
4ed7c92d | 8823 | int perf_swevent_get_recursion_context(void) |
96f6d444 | 8824 | { |
4a32fea9 | 8825 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
96f6d444 | 8826 | |
b28ab83c | 8827 | return get_recursion_context(swhash->recursion); |
96f6d444 | 8828 | } |
645e8cc0 | 8829 | EXPORT_SYMBOL_GPL(perf_swevent_get_recursion_context); |
96f6d444 | 8830 | |
98b5c2c6 | 8831 | void perf_swevent_put_recursion_context(int rctx) |
15dbf27c | 8832 | { |
4a32fea9 | 8833 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
927c7a9e | 8834 | |
b28ab83c | 8835 | put_recursion_context(swhash->recursion, rctx); |
ce71b9df | 8836 | } |
15dbf27c | 8837 | |
86038c5e | 8838 | void ___perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) |
b8e83514 | 8839 | { |
a4234bfc | 8840 | struct perf_sample_data data; |
4ed7c92d | 8841 | |
86038c5e | 8842 | if (WARN_ON_ONCE(!regs)) |
4ed7c92d | 8843 | return; |
a4234bfc | 8844 | |
fd0d000b | 8845 | perf_sample_data_init(&data, addr, 0); |
a8b0ca17 | 8846 | do_perf_sw_event(PERF_TYPE_SOFTWARE, event_id, nr, &data, regs); |
86038c5e PZI |
8847 | } |
8848 | ||
8849 | void __perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) | |
8850 | { | |
8851 | int rctx; | |
8852 | ||
8853 | preempt_disable_notrace(); | |
8854 | rctx = perf_swevent_get_recursion_context(); | |
8855 | if (unlikely(rctx < 0)) | |
8856 | goto fail; | |
8857 | ||
8858 | ___perf_sw_event(event_id, nr, regs, addr); | |
4ed7c92d PZ |
8859 | |
8860 | perf_swevent_put_recursion_context(rctx); | |
86038c5e | 8861 | fail: |
1c024eca | 8862 | preempt_enable_notrace(); |
b8e83514 PZ |
8863 | } |
8864 | ||
cdd6c482 | 8865 | static void perf_swevent_read(struct perf_event *event) |
15dbf27c | 8866 | { |
15dbf27c PZ |
8867 | } |
8868 | ||
a4eaf7f1 | 8869 | static int perf_swevent_add(struct perf_event *event, int flags) |
15dbf27c | 8870 | { |
4a32fea9 | 8871 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 8872 | struct hw_perf_event *hwc = &event->hw; |
76e1d904 FW |
8873 | struct hlist_head *head; |
8874 | ||
6c7e550f | 8875 | if (is_sampling_event(event)) { |
7b4b6658 | 8876 | hwc->last_period = hwc->sample_period; |
cdd6c482 | 8877 | perf_swevent_set_period(event); |
7b4b6658 | 8878 | } |
76e1d904 | 8879 | |
a4eaf7f1 PZ |
8880 | hwc->state = !(flags & PERF_EF_START); |
8881 | ||
b28ab83c | 8882 | head = find_swevent_head(swhash, event); |
12ca6ad2 | 8883 | if (WARN_ON_ONCE(!head)) |
76e1d904 FW |
8884 | return -EINVAL; |
8885 | ||
8886 | hlist_add_head_rcu(&event->hlist_entry, head); | |
6a694a60 | 8887 | perf_event_update_userpage(event); |
76e1d904 | 8888 | |
15dbf27c PZ |
8889 | return 0; |
8890 | } | |
8891 | ||
a4eaf7f1 | 8892 | static void perf_swevent_del(struct perf_event *event, int flags) |
15dbf27c | 8893 | { |
76e1d904 | 8894 | hlist_del_rcu(&event->hlist_entry); |
15dbf27c PZ |
8895 | } |
8896 | ||
a4eaf7f1 | 8897 | static void perf_swevent_start(struct perf_event *event, int flags) |
5c92d124 | 8898 | { |
a4eaf7f1 | 8899 | event->hw.state = 0; |
d6d020e9 | 8900 | } |
aa9c4c0f | 8901 | |
a4eaf7f1 | 8902 | static void perf_swevent_stop(struct perf_event *event, int flags) |
d6d020e9 | 8903 | { |
a4eaf7f1 | 8904 | event->hw.state = PERF_HES_STOPPED; |
bae43c99 IM |
8905 | } |
8906 | ||
49f135ed FW |
8907 | /* Deref the hlist from the update side */ |
8908 | static inline struct swevent_hlist * | |
b28ab83c | 8909 | swevent_hlist_deref(struct swevent_htable *swhash) |
49f135ed | 8910 | { |
b28ab83c PZ |
8911 | return rcu_dereference_protected(swhash->swevent_hlist, |
8912 | lockdep_is_held(&swhash->hlist_mutex)); | |
49f135ed FW |
8913 | } |
8914 | ||
b28ab83c | 8915 | static void swevent_hlist_release(struct swevent_htable *swhash) |
76e1d904 | 8916 | { |
b28ab83c | 8917 | struct swevent_hlist *hlist = swevent_hlist_deref(swhash); |
76e1d904 | 8918 | |
49f135ed | 8919 | if (!hlist) |
76e1d904 FW |
8920 | return; |
8921 | ||
70691d4a | 8922 | RCU_INIT_POINTER(swhash->swevent_hlist, NULL); |
fa4bbc4c | 8923 | kfree_rcu(hlist, rcu_head); |
76e1d904 FW |
8924 | } |
8925 | ||
3b364d7b | 8926 | static void swevent_hlist_put_cpu(int cpu) |
76e1d904 | 8927 | { |
b28ab83c | 8928 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 | 8929 | |
b28ab83c | 8930 | mutex_lock(&swhash->hlist_mutex); |
76e1d904 | 8931 | |
b28ab83c PZ |
8932 | if (!--swhash->hlist_refcount) |
8933 | swevent_hlist_release(swhash); | |
76e1d904 | 8934 | |
b28ab83c | 8935 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
8936 | } |
8937 | ||
3b364d7b | 8938 | static void swevent_hlist_put(void) |
76e1d904 FW |
8939 | { |
8940 | int cpu; | |
8941 | ||
76e1d904 | 8942 | for_each_possible_cpu(cpu) |
3b364d7b | 8943 | swevent_hlist_put_cpu(cpu); |
76e1d904 FW |
8944 | } |
8945 | ||
3b364d7b | 8946 | static int swevent_hlist_get_cpu(int cpu) |
76e1d904 | 8947 | { |
b28ab83c | 8948 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 FW |
8949 | int err = 0; |
8950 | ||
b28ab83c | 8951 | mutex_lock(&swhash->hlist_mutex); |
a63fbed7 TG |
8952 | if (!swevent_hlist_deref(swhash) && |
8953 | cpumask_test_cpu(cpu, perf_online_mask)) { | |
76e1d904 FW |
8954 | struct swevent_hlist *hlist; |
8955 | ||
8956 | hlist = kzalloc(sizeof(*hlist), GFP_KERNEL); | |
8957 | if (!hlist) { | |
8958 | err = -ENOMEM; | |
8959 | goto exit; | |
8960 | } | |
b28ab83c | 8961 | rcu_assign_pointer(swhash->swevent_hlist, hlist); |
76e1d904 | 8962 | } |
b28ab83c | 8963 | swhash->hlist_refcount++; |
9ed6060d | 8964 | exit: |
b28ab83c | 8965 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
8966 | |
8967 | return err; | |
8968 | } | |
8969 | ||
3b364d7b | 8970 | static int swevent_hlist_get(void) |
76e1d904 | 8971 | { |
3b364d7b | 8972 | int err, cpu, failed_cpu; |
76e1d904 | 8973 | |
a63fbed7 | 8974 | mutex_lock(&pmus_lock); |
76e1d904 | 8975 | for_each_possible_cpu(cpu) { |
3b364d7b | 8976 | err = swevent_hlist_get_cpu(cpu); |
76e1d904 FW |
8977 | if (err) { |
8978 | failed_cpu = cpu; | |
8979 | goto fail; | |
8980 | } | |
8981 | } | |
a63fbed7 | 8982 | mutex_unlock(&pmus_lock); |
76e1d904 | 8983 | return 0; |
9ed6060d | 8984 | fail: |
76e1d904 FW |
8985 | for_each_possible_cpu(cpu) { |
8986 | if (cpu == failed_cpu) | |
8987 | break; | |
3b364d7b | 8988 | swevent_hlist_put_cpu(cpu); |
76e1d904 | 8989 | } |
a63fbed7 | 8990 | mutex_unlock(&pmus_lock); |
76e1d904 FW |
8991 | return err; |
8992 | } | |
8993 | ||
c5905afb | 8994 | struct static_key perf_swevent_enabled[PERF_COUNT_SW_MAX]; |
95476b64 | 8995 | |
b0a873eb PZ |
8996 | static void sw_perf_event_destroy(struct perf_event *event) |
8997 | { | |
8998 | u64 event_id = event->attr.config; | |
95476b64 | 8999 | |
b0a873eb PZ |
9000 | WARN_ON(event->parent); |
9001 | ||
c5905afb | 9002 | static_key_slow_dec(&perf_swevent_enabled[event_id]); |
3b364d7b | 9003 | swevent_hlist_put(); |
b0a873eb PZ |
9004 | } |
9005 | ||
9006 | static int perf_swevent_init(struct perf_event *event) | |
9007 | { | |
8176cced | 9008 | u64 event_id = event->attr.config; |
b0a873eb PZ |
9009 | |
9010 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
9011 | return -ENOENT; | |
9012 | ||
2481c5fa SE |
9013 | /* |
9014 | * no branch sampling for software events | |
9015 | */ | |
9016 | if (has_branch_stack(event)) | |
9017 | return -EOPNOTSUPP; | |
9018 | ||
b0a873eb PZ |
9019 | switch (event_id) { |
9020 | case PERF_COUNT_SW_CPU_CLOCK: | |
9021 | case PERF_COUNT_SW_TASK_CLOCK: | |
9022 | return -ENOENT; | |
9023 | ||
9024 | default: | |
9025 | break; | |
9026 | } | |
9027 | ||
ce677831 | 9028 | if (event_id >= PERF_COUNT_SW_MAX) |
b0a873eb PZ |
9029 | return -ENOENT; |
9030 | ||
9031 | if (!event->parent) { | |
9032 | int err; | |
9033 | ||
3b364d7b | 9034 | err = swevent_hlist_get(); |
b0a873eb PZ |
9035 | if (err) |
9036 | return err; | |
9037 | ||
c5905afb | 9038 | static_key_slow_inc(&perf_swevent_enabled[event_id]); |
b0a873eb PZ |
9039 | event->destroy = sw_perf_event_destroy; |
9040 | } | |
9041 | ||
9042 | return 0; | |
9043 | } | |
9044 | ||
9045 | static struct pmu perf_swevent = { | |
89a1e187 | 9046 | .task_ctx_nr = perf_sw_context, |
95476b64 | 9047 | |
34f43927 PZ |
9048 | .capabilities = PERF_PMU_CAP_NO_NMI, |
9049 | ||
b0a873eb | 9050 | .event_init = perf_swevent_init, |
a4eaf7f1 PZ |
9051 | .add = perf_swevent_add, |
9052 | .del = perf_swevent_del, | |
9053 | .start = perf_swevent_start, | |
9054 | .stop = perf_swevent_stop, | |
1c024eca | 9055 | .read = perf_swevent_read, |
1c024eca PZ |
9056 | }; |
9057 | ||
b0a873eb PZ |
9058 | #ifdef CONFIG_EVENT_TRACING |
9059 | ||
1c024eca PZ |
9060 | static int perf_tp_filter_match(struct perf_event *event, |
9061 | struct perf_sample_data *data) | |
9062 | { | |
7e3f977e | 9063 | void *record = data->raw->frag.data; |
1c024eca | 9064 | |
b71b437e PZ |
9065 | /* only top level events have filters set */ |
9066 | if (event->parent) | |
9067 | event = event->parent; | |
9068 | ||
1c024eca PZ |
9069 | if (likely(!event->filter) || filter_match_preds(event->filter, record)) |
9070 | return 1; | |
9071 | return 0; | |
9072 | } | |
9073 | ||
9074 | static int perf_tp_event_match(struct perf_event *event, | |
9075 | struct perf_sample_data *data, | |
9076 | struct pt_regs *regs) | |
9077 | { | |
a0f7d0f7 FW |
9078 | if (event->hw.state & PERF_HES_STOPPED) |
9079 | return 0; | |
580d607c | 9080 | /* |
9fd2e48b | 9081 | * If exclude_kernel, only trace user-space tracepoints (uprobes) |
580d607c | 9082 | */ |
9fd2e48b | 9083 | if (event->attr.exclude_kernel && !user_mode(regs)) |
1c024eca PZ |
9084 | return 0; |
9085 | ||
9086 | if (!perf_tp_filter_match(event, data)) | |
9087 | return 0; | |
9088 | ||
9089 | return 1; | |
9090 | } | |
9091 | ||
85b67bcb AS |
9092 | void perf_trace_run_bpf_submit(void *raw_data, int size, int rctx, |
9093 | struct trace_event_call *call, u64 count, | |
9094 | struct pt_regs *regs, struct hlist_head *head, | |
9095 | struct task_struct *task) | |
9096 | { | |
e87c6bc3 | 9097 | if (bpf_prog_array_valid(call)) { |
85b67bcb | 9098 | *(struct pt_regs **)raw_data = regs; |
e87c6bc3 | 9099 | if (!trace_call_bpf(call, raw_data) || hlist_empty(head)) { |
85b67bcb AS |
9100 | perf_swevent_put_recursion_context(rctx); |
9101 | return; | |
9102 | } | |
9103 | } | |
9104 | perf_tp_event(call->event.type, count, raw_data, size, regs, head, | |
8fd0fbbe | 9105 | rctx, task); |
85b67bcb AS |
9106 | } |
9107 | EXPORT_SYMBOL_GPL(perf_trace_run_bpf_submit); | |
9108 | ||
1e1dcd93 | 9109 | void perf_tp_event(u16 event_type, u64 count, void *record, int entry_size, |
e6dab5ff | 9110 | struct pt_regs *regs, struct hlist_head *head, int rctx, |
8fd0fbbe | 9111 | struct task_struct *task) |
95476b64 FW |
9112 | { |
9113 | struct perf_sample_data data; | |
8fd0fbbe | 9114 | struct perf_event *event; |
1c024eca | 9115 | |
95476b64 | 9116 | struct perf_raw_record raw = { |
7e3f977e DB |
9117 | .frag = { |
9118 | .size = entry_size, | |
9119 | .data = record, | |
9120 | }, | |
95476b64 FW |
9121 | }; |
9122 | ||
1e1dcd93 | 9123 | perf_sample_data_init(&data, 0, 0); |
95476b64 FW |
9124 | data.raw = &raw; |
9125 | ||
1e1dcd93 AS |
9126 | perf_trace_buf_update(record, event_type); |
9127 | ||
8fd0fbbe | 9128 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
1c024eca | 9129 | if (perf_tp_event_match(event, &data, regs)) |
a8b0ca17 | 9130 | perf_swevent_event(event, count, &data, regs); |
4f41c013 | 9131 | } |
ecc55f84 | 9132 | |
e6dab5ff AV |
9133 | /* |
9134 | * If we got specified a target task, also iterate its context and | |
9135 | * deliver this event there too. | |
9136 | */ | |
9137 | if (task && task != current) { | |
9138 | struct perf_event_context *ctx; | |
9139 | struct trace_entry *entry = record; | |
9140 | ||
9141 | rcu_read_lock(); | |
9142 | ctx = rcu_dereference(task->perf_event_ctxp[perf_sw_context]); | |
9143 | if (!ctx) | |
9144 | goto unlock; | |
9145 | ||
9146 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
cd6fb677 JO |
9147 | if (event->cpu != smp_processor_id()) |
9148 | continue; | |
e6dab5ff AV |
9149 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
9150 | continue; | |
9151 | if (event->attr.config != entry->type) | |
9152 | continue; | |
9153 | if (perf_tp_event_match(event, &data, regs)) | |
9154 | perf_swevent_event(event, count, &data, regs); | |
9155 | } | |
9156 | unlock: | |
9157 | rcu_read_unlock(); | |
9158 | } | |
9159 | ||
ecc55f84 | 9160 | perf_swevent_put_recursion_context(rctx); |
95476b64 FW |
9161 | } |
9162 | EXPORT_SYMBOL_GPL(perf_tp_event); | |
9163 | ||
cdd6c482 | 9164 | static void tp_perf_event_destroy(struct perf_event *event) |
e077df4f | 9165 | { |
1c024eca | 9166 | perf_trace_destroy(event); |
e077df4f PZ |
9167 | } |
9168 | ||
b0a873eb | 9169 | static int perf_tp_event_init(struct perf_event *event) |
e077df4f | 9170 | { |
76e1d904 FW |
9171 | int err; |
9172 | ||
b0a873eb PZ |
9173 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
9174 | return -ENOENT; | |
9175 | ||
2481c5fa SE |
9176 | /* |
9177 | * no branch sampling for tracepoint events | |
9178 | */ | |
9179 | if (has_branch_stack(event)) | |
9180 | return -EOPNOTSUPP; | |
9181 | ||
1c024eca PZ |
9182 | err = perf_trace_init(event); |
9183 | if (err) | |
b0a873eb | 9184 | return err; |
e077df4f | 9185 | |
cdd6c482 | 9186 | event->destroy = tp_perf_event_destroy; |
e077df4f | 9187 | |
b0a873eb PZ |
9188 | return 0; |
9189 | } | |
9190 | ||
9191 | static struct pmu perf_tracepoint = { | |
89a1e187 PZ |
9192 | .task_ctx_nr = perf_sw_context, |
9193 | ||
b0a873eb | 9194 | .event_init = perf_tp_event_init, |
a4eaf7f1 PZ |
9195 | .add = perf_trace_add, |
9196 | .del = perf_trace_del, | |
9197 | .start = perf_swevent_start, | |
9198 | .stop = perf_swevent_stop, | |
b0a873eb | 9199 | .read = perf_swevent_read, |
b0a873eb PZ |
9200 | }; |
9201 | ||
33ea4b24 | 9202 | #if defined(CONFIG_KPROBE_EVENTS) || defined(CONFIG_UPROBE_EVENTS) |
e12f03d7 SL |
9203 | /* |
9204 | * Flags in config, used by dynamic PMU kprobe and uprobe | |
9205 | * The flags should match following PMU_FORMAT_ATTR(). | |
9206 | * | |
9207 | * PERF_PROBE_CONFIG_IS_RETPROBE if set, create kretprobe/uretprobe | |
9208 | * if not set, create kprobe/uprobe | |
a6ca88b2 SL |
9209 | * |
9210 | * The following values specify a reference counter (or semaphore in the | |
9211 | * terminology of tools like dtrace, systemtap, etc.) Userspace Statically | |
9212 | * Defined Tracepoints (USDT). Currently, we use 40 bit for the offset. | |
9213 | * | |
9214 | * PERF_UPROBE_REF_CTR_OFFSET_BITS # of bits in config as th offset | |
9215 | * PERF_UPROBE_REF_CTR_OFFSET_SHIFT # of bits to shift left | |
e12f03d7 SL |
9216 | */ |
9217 | enum perf_probe_config { | |
9218 | PERF_PROBE_CONFIG_IS_RETPROBE = 1U << 0, /* [k,u]retprobe */ | |
a6ca88b2 SL |
9219 | PERF_UPROBE_REF_CTR_OFFSET_BITS = 32, |
9220 | PERF_UPROBE_REF_CTR_OFFSET_SHIFT = 64 - PERF_UPROBE_REF_CTR_OFFSET_BITS, | |
e12f03d7 SL |
9221 | }; |
9222 | ||
9223 | PMU_FORMAT_ATTR(retprobe, "config:0"); | |
a6ca88b2 | 9224 | #endif |
e12f03d7 | 9225 | |
a6ca88b2 SL |
9226 | #ifdef CONFIG_KPROBE_EVENTS |
9227 | static struct attribute *kprobe_attrs[] = { | |
e12f03d7 SL |
9228 | &format_attr_retprobe.attr, |
9229 | NULL, | |
9230 | }; | |
9231 | ||
a6ca88b2 | 9232 | static struct attribute_group kprobe_format_group = { |
e12f03d7 | 9233 | .name = "format", |
a6ca88b2 | 9234 | .attrs = kprobe_attrs, |
e12f03d7 SL |
9235 | }; |
9236 | ||
a6ca88b2 SL |
9237 | static const struct attribute_group *kprobe_attr_groups[] = { |
9238 | &kprobe_format_group, | |
e12f03d7 SL |
9239 | NULL, |
9240 | }; | |
9241 | ||
9242 | static int perf_kprobe_event_init(struct perf_event *event); | |
9243 | static struct pmu perf_kprobe = { | |
9244 | .task_ctx_nr = perf_sw_context, | |
9245 | .event_init = perf_kprobe_event_init, | |
9246 | .add = perf_trace_add, | |
9247 | .del = perf_trace_del, | |
9248 | .start = perf_swevent_start, | |
9249 | .stop = perf_swevent_stop, | |
9250 | .read = perf_swevent_read, | |
a6ca88b2 | 9251 | .attr_groups = kprobe_attr_groups, |
e12f03d7 SL |
9252 | }; |
9253 | ||
9254 | static int perf_kprobe_event_init(struct perf_event *event) | |
9255 | { | |
9256 | int err; | |
9257 | bool is_retprobe; | |
9258 | ||
9259 | if (event->attr.type != perf_kprobe.type) | |
9260 | return -ENOENT; | |
32e6e967 SL |
9261 | |
9262 | if (!capable(CAP_SYS_ADMIN)) | |
9263 | return -EACCES; | |
9264 | ||
e12f03d7 SL |
9265 | /* |
9266 | * no branch sampling for probe events | |
9267 | */ | |
9268 | if (has_branch_stack(event)) | |
9269 | return -EOPNOTSUPP; | |
9270 | ||
9271 | is_retprobe = event->attr.config & PERF_PROBE_CONFIG_IS_RETPROBE; | |
9272 | err = perf_kprobe_init(event, is_retprobe); | |
9273 | if (err) | |
9274 | return err; | |
9275 | ||
9276 | event->destroy = perf_kprobe_destroy; | |
9277 | ||
9278 | return 0; | |
9279 | } | |
9280 | #endif /* CONFIG_KPROBE_EVENTS */ | |
9281 | ||
33ea4b24 | 9282 | #ifdef CONFIG_UPROBE_EVENTS |
a6ca88b2 SL |
9283 | PMU_FORMAT_ATTR(ref_ctr_offset, "config:32-63"); |
9284 | ||
9285 | static struct attribute *uprobe_attrs[] = { | |
9286 | &format_attr_retprobe.attr, | |
9287 | &format_attr_ref_ctr_offset.attr, | |
9288 | NULL, | |
9289 | }; | |
9290 | ||
9291 | static struct attribute_group uprobe_format_group = { | |
9292 | .name = "format", | |
9293 | .attrs = uprobe_attrs, | |
9294 | }; | |
9295 | ||
9296 | static const struct attribute_group *uprobe_attr_groups[] = { | |
9297 | &uprobe_format_group, | |
9298 | NULL, | |
9299 | }; | |
9300 | ||
33ea4b24 SL |
9301 | static int perf_uprobe_event_init(struct perf_event *event); |
9302 | static struct pmu perf_uprobe = { | |
9303 | .task_ctx_nr = perf_sw_context, | |
9304 | .event_init = perf_uprobe_event_init, | |
9305 | .add = perf_trace_add, | |
9306 | .del = perf_trace_del, | |
9307 | .start = perf_swevent_start, | |
9308 | .stop = perf_swevent_stop, | |
9309 | .read = perf_swevent_read, | |
a6ca88b2 | 9310 | .attr_groups = uprobe_attr_groups, |
33ea4b24 SL |
9311 | }; |
9312 | ||
9313 | static int perf_uprobe_event_init(struct perf_event *event) | |
9314 | { | |
9315 | int err; | |
a6ca88b2 | 9316 | unsigned long ref_ctr_offset; |
33ea4b24 SL |
9317 | bool is_retprobe; |
9318 | ||
9319 | if (event->attr.type != perf_uprobe.type) | |
9320 | return -ENOENT; | |
32e6e967 SL |
9321 | |
9322 | if (!capable(CAP_SYS_ADMIN)) | |
9323 | return -EACCES; | |
9324 | ||
33ea4b24 SL |
9325 | /* |
9326 | * no branch sampling for probe events | |
9327 | */ | |
9328 | if (has_branch_stack(event)) | |
9329 | return -EOPNOTSUPP; | |
9330 | ||
9331 | is_retprobe = event->attr.config & PERF_PROBE_CONFIG_IS_RETPROBE; | |
a6ca88b2 SL |
9332 | ref_ctr_offset = event->attr.config >> PERF_UPROBE_REF_CTR_OFFSET_SHIFT; |
9333 | err = perf_uprobe_init(event, ref_ctr_offset, is_retprobe); | |
33ea4b24 SL |
9334 | if (err) |
9335 | return err; | |
9336 | ||
9337 | event->destroy = perf_uprobe_destroy; | |
9338 | ||
9339 | return 0; | |
9340 | } | |
9341 | #endif /* CONFIG_UPROBE_EVENTS */ | |
9342 | ||
b0a873eb PZ |
9343 | static inline void perf_tp_register(void) |
9344 | { | |
2e80a82a | 9345 | perf_pmu_register(&perf_tracepoint, "tracepoint", PERF_TYPE_TRACEPOINT); |
e12f03d7 SL |
9346 | #ifdef CONFIG_KPROBE_EVENTS |
9347 | perf_pmu_register(&perf_kprobe, "kprobe", -1); | |
9348 | #endif | |
33ea4b24 SL |
9349 | #ifdef CONFIG_UPROBE_EVENTS |
9350 | perf_pmu_register(&perf_uprobe, "uprobe", -1); | |
9351 | #endif | |
e077df4f | 9352 | } |
6fb2915d | 9353 | |
6fb2915d LZ |
9354 | static void perf_event_free_filter(struct perf_event *event) |
9355 | { | |
9356 | ftrace_profile_free_filter(event); | |
9357 | } | |
9358 | ||
aa6a5f3c AS |
9359 | #ifdef CONFIG_BPF_SYSCALL |
9360 | static void bpf_overflow_handler(struct perf_event *event, | |
9361 | struct perf_sample_data *data, | |
9362 | struct pt_regs *regs) | |
9363 | { | |
9364 | struct bpf_perf_event_data_kern ctx = { | |
9365 | .data = data, | |
7d9285e8 | 9366 | .event = event, |
aa6a5f3c AS |
9367 | }; |
9368 | int ret = 0; | |
9369 | ||
c895f6f7 | 9370 | ctx.regs = perf_arch_bpf_user_pt_regs(regs); |
aa6a5f3c AS |
9371 | preempt_disable(); |
9372 | if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) | |
9373 | goto out; | |
9374 | rcu_read_lock(); | |
88575199 | 9375 | ret = BPF_PROG_RUN(event->prog, &ctx); |
aa6a5f3c AS |
9376 | rcu_read_unlock(); |
9377 | out: | |
9378 | __this_cpu_dec(bpf_prog_active); | |
9379 | preempt_enable(); | |
9380 | if (!ret) | |
9381 | return; | |
9382 | ||
9383 | event->orig_overflow_handler(event, data, regs); | |
9384 | } | |
9385 | ||
9386 | static int perf_event_set_bpf_handler(struct perf_event *event, u32 prog_fd) | |
9387 | { | |
9388 | struct bpf_prog *prog; | |
9389 | ||
9390 | if (event->overflow_handler_context) | |
9391 | /* hw breakpoint or kernel counter */ | |
9392 | return -EINVAL; | |
9393 | ||
9394 | if (event->prog) | |
9395 | return -EEXIST; | |
9396 | ||
9397 | prog = bpf_prog_get_type(prog_fd, BPF_PROG_TYPE_PERF_EVENT); | |
9398 | if (IS_ERR(prog)) | |
9399 | return PTR_ERR(prog); | |
9400 | ||
9401 | event->prog = prog; | |
9402 | event->orig_overflow_handler = READ_ONCE(event->overflow_handler); | |
9403 | WRITE_ONCE(event->overflow_handler, bpf_overflow_handler); | |
9404 | return 0; | |
9405 | } | |
9406 | ||
9407 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
9408 | { | |
9409 | struct bpf_prog *prog = event->prog; | |
9410 | ||
9411 | if (!prog) | |
9412 | return; | |
9413 | ||
9414 | WRITE_ONCE(event->overflow_handler, event->orig_overflow_handler); | |
9415 | event->prog = NULL; | |
9416 | bpf_prog_put(prog); | |
9417 | } | |
9418 | #else | |
9419 | static int perf_event_set_bpf_handler(struct perf_event *event, u32 prog_fd) | |
9420 | { | |
9421 | return -EOPNOTSUPP; | |
9422 | } | |
9423 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
9424 | { | |
9425 | } | |
9426 | #endif | |
9427 | ||
e12f03d7 SL |
9428 | /* |
9429 | * returns true if the event is a tracepoint, or a kprobe/upprobe created | |
9430 | * with perf_event_open() | |
9431 | */ | |
9432 | static inline bool perf_event_is_tracing(struct perf_event *event) | |
9433 | { | |
9434 | if (event->pmu == &perf_tracepoint) | |
9435 | return true; | |
9436 | #ifdef CONFIG_KPROBE_EVENTS | |
9437 | if (event->pmu == &perf_kprobe) | |
9438 | return true; | |
33ea4b24 SL |
9439 | #endif |
9440 | #ifdef CONFIG_UPROBE_EVENTS | |
9441 | if (event->pmu == &perf_uprobe) | |
9442 | return true; | |
e12f03d7 SL |
9443 | #endif |
9444 | return false; | |
9445 | } | |
9446 | ||
2541517c AS |
9447 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
9448 | { | |
cf5f5cea | 9449 | bool is_kprobe, is_tracepoint, is_syscall_tp; |
2541517c | 9450 | struct bpf_prog *prog; |
e87c6bc3 | 9451 | int ret; |
2541517c | 9452 | |
e12f03d7 | 9453 | if (!perf_event_is_tracing(event)) |
f91840a3 | 9454 | return perf_event_set_bpf_handler(event, prog_fd); |
2541517c | 9455 | |
98b5c2c6 AS |
9456 | is_kprobe = event->tp_event->flags & TRACE_EVENT_FL_UKPROBE; |
9457 | is_tracepoint = event->tp_event->flags & TRACE_EVENT_FL_TRACEPOINT; | |
cf5f5cea YS |
9458 | is_syscall_tp = is_syscall_trace_event(event->tp_event); |
9459 | if (!is_kprobe && !is_tracepoint && !is_syscall_tp) | |
98b5c2c6 | 9460 | /* bpf programs can only be attached to u/kprobe or tracepoint */ |
2541517c AS |
9461 | return -EINVAL; |
9462 | ||
9463 | prog = bpf_prog_get(prog_fd); | |
9464 | if (IS_ERR(prog)) | |
9465 | return PTR_ERR(prog); | |
9466 | ||
98b5c2c6 | 9467 | if ((is_kprobe && prog->type != BPF_PROG_TYPE_KPROBE) || |
cf5f5cea YS |
9468 | (is_tracepoint && prog->type != BPF_PROG_TYPE_TRACEPOINT) || |
9469 | (is_syscall_tp && prog->type != BPF_PROG_TYPE_TRACEPOINT)) { | |
2541517c AS |
9470 | /* valid fd, but invalid bpf program type */ |
9471 | bpf_prog_put(prog); | |
9472 | return -EINVAL; | |
9473 | } | |
9474 | ||
9802d865 JB |
9475 | /* Kprobe override only works for kprobes, not uprobes. */ |
9476 | if (prog->kprobe_override && | |
9477 | !(event->tp_event->flags & TRACE_EVENT_FL_KPROBE)) { | |
9478 | bpf_prog_put(prog); | |
9479 | return -EINVAL; | |
9480 | } | |
9481 | ||
cf5f5cea | 9482 | if (is_tracepoint || is_syscall_tp) { |
32bbe007 AS |
9483 | int off = trace_event_get_offsets(event->tp_event); |
9484 | ||
9485 | if (prog->aux->max_ctx_offset > off) { | |
9486 | bpf_prog_put(prog); | |
9487 | return -EACCES; | |
9488 | } | |
9489 | } | |
2541517c | 9490 | |
e87c6bc3 YS |
9491 | ret = perf_event_attach_bpf_prog(event, prog); |
9492 | if (ret) | |
9493 | bpf_prog_put(prog); | |
9494 | return ret; | |
2541517c AS |
9495 | } |
9496 | ||
9497 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
9498 | { | |
e12f03d7 | 9499 | if (!perf_event_is_tracing(event)) { |
0b4c6841 | 9500 | perf_event_free_bpf_handler(event); |
2541517c | 9501 | return; |
2541517c | 9502 | } |
e87c6bc3 | 9503 | perf_event_detach_bpf_prog(event); |
2541517c AS |
9504 | } |
9505 | ||
e077df4f | 9506 | #else |
6fb2915d | 9507 | |
b0a873eb | 9508 | static inline void perf_tp_register(void) |
e077df4f | 9509 | { |
e077df4f | 9510 | } |
6fb2915d | 9511 | |
6fb2915d LZ |
9512 | static void perf_event_free_filter(struct perf_event *event) |
9513 | { | |
9514 | } | |
9515 | ||
2541517c AS |
9516 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
9517 | { | |
9518 | return -ENOENT; | |
9519 | } | |
9520 | ||
9521 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
9522 | { | |
9523 | } | |
07b139c8 | 9524 | #endif /* CONFIG_EVENT_TRACING */ |
e077df4f | 9525 | |
24f1e32c | 9526 | #ifdef CONFIG_HAVE_HW_BREAKPOINT |
f5ffe02e | 9527 | void perf_bp_event(struct perf_event *bp, void *data) |
24f1e32c | 9528 | { |
f5ffe02e FW |
9529 | struct perf_sample_data sample; |
9530 | struct pt_regs *regs = data; | |
9531 | ||
fd0d000b | 9532 | perf_sample_data_init(&sample, bp->attr.bp_addr, 0); |
f5ffe02e | 9533 | |
a4eaf7f1 | 9534 | if (!bp->hw.state && !perf_exclude_event(bp, regs)) |
a8b0ca17 | 9535 | perf_swevent_event(bp, 1, &sample, regs); |
24f1e32c FW |
9536 | } |
9537 | #endif | |
9538 | ||
375637bc AS |
9539 | /* |
9540 | * Allocate a new address filter | |
9541 | */ | |
9542 | static struct perf_addr_filter * | |
9543 | perf_addr_filter_new(struct perf_event *event, struct list_head *filters) | |
9544 | { | |
9545 | int node = cpu_to_node(event->cpu == -1 ? 0 : event->cpu); | |
9546 | struct perf_addr_filter *filter; | |
9547 | ||
9548 | filter = kzalloc_node(sizeof(*filter), GFP_KERNEL, node); | |
9549 | if (!filter) | |
9550 | return NULL; | |
9551 | ||
9552 | INIT_LIST_HEAD(&filter->entry); | |
9553 | list_add_tail(&filter->entry, filters); | |
9554 | ||
9555 | return filter; | |
9556 | } | |
9557 | ||
9558 | static void free_filters_list(struct list_head *filters) | |
9559 | { | |
9560 | struct perf_addr_filter *filter, *iter; | |
9561 | ||
9562 | list_for_each_entry_safe(filter, iter, filters, entry) { | |
9511bce9 | 9563 | path_put(&filter->path); |
375637bc AS |
9564 | list_del(&filter->entry); |
9565 | kfree(filter); | |
9566 | } | |
9567 | } | |
9568 | ||
9569 | /* | |
9570 | * Free existing address filters and optionally install new ones | |
9571 | */ | |
9572 | static void perf_addr_filters_splice(struct perf_event *event, | |
9573 | struct list_head *head) | |
9574 | { | |
9575 | unsigned long flags; | |
9576 | LIST_HEAD(list); | |
9577 | ||
9578 | if (!has_addr_filter(event)) | |
9579 | return; | |
9580 | ||
9581 | /* don't bother with children, they don't have their own filters */ | |
9582 | if (event->parent) | |
9583 | return; | |
9584 | ||
9585 | raw_spin_lock_irqsave(&event->addr_filters.lock, flags); | |
9586 | ||
9587 | list_splice_init(&event->addr_filters.list, &list); | |
9588 | if (head) | |
9589 | list_splice(head, &event->addr_filters.list); | |
9590 | ||
9591 | raw_spin_unlock_irqrestore(&event->addr_filters.lock, flags); | |
9592 | ||
9593 | free_filters_list(&list); | |
9594 | } | |
9595 | ||
9596 | /* | |
9597 | * Scan through mm's vmas and see if one of them matches the | |
9598 | * @filter; if so, adjust filter's address range. | |
9599 | * Called with mm::mmap_sem down for reading. | |
9600 | */ | |
c60f83b8 AS |
9601 | static void perf_addr_filter_apply(struct perf_addr_filter *filter, |
9602 | struct mm_struct *mm, | |
9603 | struct perf_addr_filter_range *fr) | |
375637bc AS |
9604 | { |
9605 | struct vm_area_struct *vma; | |
9606 | ||
9607 | for (vma = mm->mmap; vma; vma = vma->vm_next) { | |
c60f83b8 | 9608 | if (!vma->vm_file) |
375637bc AS |
9609 | continue; |
9610 | ||
c60f83b8 AS |
9611 | if (perf_addr_filter_vma_adjust(filter, vma, fr)) |
9612 | return; | |
375637bc | 9613 | } |
375637bc AS |
9614 | } |
9615 | ||
9616 | /* | |
9617 | * Update event's address range filters based on the | |
9618 | * task's existing mappings, if any. | |
9619 | */ | |
9620 | static void perf_event_addr_filters_apply(struct perf_event *event) | |
9621 | { | |
9622 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
9623 | struct task_struct *task = READ_ONCE(event->ctx->task); | |
9624 | struct perf_addr_filter *filter; | |
9625 | struct mm_struct *mm = NULL; | |
9626 | unsigned int count = 0; | |
9627 | unsigned long flags; | |
9628 | ||
9629 | /* | |
9630 | * We may observe TASK_TOMBSTONE, which means that the event tear-down | |
9631 | * will stop on the parent's child_mutex that our caller is also holding | |
9632 | */ | |
9633 | if (task == TASK_TOMBSTONE) | |
9634 | return; | |
9635 | ||
52a44f83 AS |
9636 | if (ifh->nr_file_filters) { |
9637 | mm = get_task_mm(event->ctx->task); | |
9638 | if (!mm) | |
9639 | goto restart; | |
375637bc | 9640 | |
52a44f83 AS |
9641 | down_read(&mm->mmap_sem); |
9642 | } | |
375637bc AS |
9643 | |
9644 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
9645 | list_for_each_entry(filter, &ifh->list, entry) { | |
52a44f83 AS |
9646 | if (filter->path.dentry) { |
9647 | /* | |
9648 | * Adjust base offset if the filter is associated to a | |
9649 | * binary that needs to be mapped: | |
9650 | */ | |
9651 | event->addr_filter_ranges[count].start = 0; | |
9652 | event->addr_filter_ranges[count].size = 0; | |
375637bc | 9653 | |
c60f83b8 | 9654 | perf_addr_filter_apply(filter, mm, &event->addr_filter_ranges[count]); |
52a44f83 AS |
9655 | } else { |
9656 | event->addr_filter_ranges[count].start = filter->offset; | |
9657 | event->addr_filter_ranges[count].size = filter->size; | |
9658 | } | |
375637bc AS |
9659 | |
9660 | count++; | |
9661 | } | |
9662 | ||
9663 | event->addr_filters_gen++; | |
9664 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
9665 | ||
52a44f83 AS |
9666 | if (ifh->nr_file_filters) { |
9667 | up_read(&mm->mmap_sem); | |
375637bc | 9668 | |
52a44f83 AS |
9669 | mmput(mm); |
9670 | } | |
375637bc AS |
9671 | |
9672 | restart: | |
767ae086 | 9673 | perf_event_stop(event, 1); |
375637bc AS |
9674 | } |
9675 | ||
9676 | /* | |
9677 | * Address range filtering: limiting the data to certain | |
9678 | * instruction address ranges. Filters are ioctl()ed to us from | |
9679 | * userspace as ascii strings. | |
9680 | * | |
9681 | * Filter string format: | |
9682 | * | |
9683 | * ACTION RANGE_SPEC | |
9684 | * where ACTION is one of the | |
9685 | * * "filter": limit the trace to this region | |
9686 | * * "start": start tracing from this address | |
9687 | * * "stop": stop tracing at this address/region; | |
9688 | * RANGE_SPEC is | |
9689 | * * for kernel addresses: <start address>[/<size>] | |
9690 | * * for object files: <start address>[/<size>]@</path/to/object/file> | |
9691 | * | |
6ed70cf3 AS |
9692 | * if <size> is not specified or is zero, the range is treated as a single |
9693 | * address; not valid for ACTION=="filter". | |
375637bc AS |
9694 | */ |
9695 | enum { | |
e96271f3 | 9696 | IF_ACT_NONE = -1, |
375637bc AS |
9697 | IF_ACT_FILTER, |
9698 | IF_ACT_START, | |
9699 | IF_ACT_STOP, | |
9700 | IF_SRC_FILE, | |
9701 | IF_SRC_KERNEL, | |
9702 | IF_SRC_FILEADDR, | |
9703 | IF_SRC_KERNELADDR, | |
9704 | }; | |
9705 | ||
9706 | enum { | |
9707 | IF_STATE_ACTION = 0, | |
9708 | IF_STATE_SOURCE, | |
9709 | IF_STATE_END, | |
9710 | }; | |
9711 | ||
9712 | static const match_table_t if_tokens = { | |
9713 | { IF_ACT_FILTER, "filter" }, | |
9714 | { IF_ACT_START, "start" }, | |
9715 | { IF_ACT_STOP, "stop" }, | |
9716 | { IF_SRC_FILE, "%u/%u@%s" }, | |
9717 | { IF_SRC_KERNEL, "%u/%u" }, | |
9718 | { IF_SRC_FILEADDR, "%u@%s" }, | |
9719 | { IF_SRC_KERNELADDR, "%u" }, | |
e96271f3 | 9720 | { IF_ACT_NONE, NULL }, |
375637bc AS |
9721 | }; |
9722 | ||
9723 | /* | |
9724 | * Address filter string parser | |
9725 | */ | |
9726 | static int | |
9727 | perf_event_parse_addr_filter(struct perf_event *event, char *fstr, | |
9728 | struct list_head *filters) | |
9729 | { | |
9730 | struct perf_addr_filter *filter = NULL; | |
9731 | char *start, *orig, *filename = NULL; | |
375637bc AS |
9732 | substring_t args[MAX_OPT_ARGS]; |
9733 | int state = IF_STATE_ACTION, token; | |
9734 | unsigned int kernel = 0; | |
9735 | int ret = -EINVAL; | |
9736 | ||
9737 | orig = fstr = kstrdup(fstr, GFP_KERNEL); | |
9738 | if (!fstr) | |
9739 | return -ENOMEM; | |
9740 | ||
9741 | while ((start = strsep(&fstr, " ,\n")) != NULL) { | |
6ed70cf3 AS |
9742 | static const enum perf_addr_filter_action_t actions[] = { |
9743 | [IF_ACT_FILTER] = PERF_ADDR_FILTER_ACTION_FILTER, | |
9744 | [IF_ACT_START] = PERF_ADDR_FILTER_ACTION_START, | |
9745 | [IF_ACT_STOP] = PERF_ADDR_FILTER_ACTION_STOP, | |
9746 | }; | |
375637bc AS |
9747 | ret = -EINVAL; |
9748 | ||
9749 | if (!*start) | |
9750 | continue; | |
9751 | ||
9752 | /* filter definition begins */ | |
9753 | if (state == IF_STATE_ACTION) { | |
9754 | filter = perf_addr_filter_new(event, filters); | |
9755 | if (!filter) | |
9756 | goto fail; | |
9757 | } | |
9758 | ||
9759 | token = match_token(start, if_tokens, args); | |
9760 | switch (token) { | |
9761 | case IF_ACT_FILTER: | |
9762 | case IF_ACT_START: | |
375637bc AS |
9763 | case IF_ACT_STOP: |
9764 | if (state != IF_STATE_ACTION) | |
9765 | goto fail; | |
9766 | ||
6ed70cf3 | 9767 | filter->action = actions[token]; |
375637bc AS |
9768 | state = IF_STATE_SOURCE; |
9769 | break; | |
9770 | ||
9771 | case IF_SRC_KERNELADDR: | |
9772 | case IF_SRC_KERNEL: | |
9773 | kernel = 1; | |
10c3405f | 9774 | /* fall through */ |
375637bc AS |
9775 | |
9776 | case IF_SRC_FILEADDR: | |
9777 | case IF_SRC_FILE: | |
9778 | if (state != IF_STATE_SOURCE) | |
9779 | goto fail; | |
9780 | ||
375637bc AS |
9781 | *args[0].to = 0; |
9782 | ret = kstrtoul(args[0].from, 0, &filter->offset); | |
9783 | if (ret) | |
9784 | goto fail; | |
9785 | ||
6ed70cf3 | 9786 | if (token == IF_SRC_KERNEL || token == IF_SRC_FILE) { |
375637bc AS |
9787 | *args[1].to = 0; |
9788 | ret = kstrtoul(args[1].from, 0, &filter->size); | |
9789 | if (ret) | |
9790 | goto fail; | |
9791 | } | |
9792 | ||
4059ffd0 | 9793 | if (token == IF_SRC_FILE || token == IF_SRC_FILEADDR) { |
6ed70cf3 | 9794 | int fpos = token == IF_SRC_FILE ? 2 : 1; |
4059ffd0 MP |
9795 | |
9796 | filename = match_strdup(&args[fpos]); | |
375637bc AS |
9797 | if (!filename) { |
9798 | ret = -ENOMEM; | |
9799 | goto fail; | |
9800 | } | |
9801 | } | |
9802 | ||
9803 | state = IF_STATE_END; | |
9804 | break; | |
9805 | ||
9806 | default: | |
9807 | goto fail; | |
9808 | } | |
9809 | ||
9810 | /* | |
9811 | * Filter definition is fully parsed, validate and install it. | |
9812 | * Make sure that it doesn't contradict itself or the event's | |
9813 | * attribute. | |
9814 | */ | |
9815 | if (state == IF_STATE_END) { | |
9ccbfbb1 | 9816 | ret = -EINVAL; |
375637bc AS |
9817 | if (kernel && event->attr.exclude_kernel) |
9818 | goto fail; | |
9819 | ||
6ed70cf3 AS |
9820 | /* |
9821 | * ACTION "filter" must have a non-zero length region | |
9822 | * specified. | |
9823 | */ | |
9824 | if (filter->action == PERF_ADDR_FILTER_ACTION_FILTER && | |
9825 | !filter->size) | |
9826 | goto fail; | |
9827 | ||
375637bc AS |
9828 | if (!kernel) { |
9829 | if (!filename) | |
9830 | goto fail; | |
9831 | ||
6ce77bfd AS |
9832 | /* |
9833 | * For now, we only support file-based filters | |
9834 | * in per-task events; doing so for CPU-wide | |
9835 | * events requires additional context switching | |
9836 | * trickery, since same object code will be | |
9837 | * mapped at different virtual addresses in | |
9838 | * different processes. | |
9839 | */ | |
9840 | ret = -EOPNOTSUPP; | |
9841 | if (!event->ctx->task) | |
9842 | goto fail_free_name; | |
9843 | ||
375637bc | 9844 | /* look up the path and grab its inode */ |
9511bce9 SL |
9845 | ret = kern_path(filename, LOOKUP_FOLLOW, |
9846 | &filter->path); | |
375637bc AS |
9847 | if (ret) |
9848 | goto fail_free_name; | |
9849 | ||
375637bc AS |
9850 | kfree(filename); |
9851 | filename = NULL; | |
9852 | ||
9853 | ret = -EINVAL; | |
9511bce9 SL |
9854 | if (!filter->path.dentry || |
9855 | !S_ISREG(d_inode(filter->path.dentry) | |
9856 | ->i_mode)) | |
375637bc | 9857 | goto fail; |
6ce77bfd AS |
9858 | |
9859 | event->addr_filters.nr_file_filters++; | |
375637bc AS |
9860 | } |
9861 | ||
9862 | /* ready to consume more filters */ | |
9863 | state = IF_STATE_ACTION; | |
9864 | filter = NULL; | |
9865 | } | |
9866 | } | |
9867 | ||
9868 | if (state != IF_STATE_ACTION) | |
9869 | goto fail; | |
9870 | ||
9871 | kfree(orig); | |
9872 | ||
9873 | return 0; | |
9874 | ||
9875 | fail_free_name: | |
9876 | kfree(filename); | |
9877 | fail: | |
9878 | free_filters_list(filters); | |
9879 | kfree(orig); | |
9880 | ||
9881 | return ret; | |
9882 | } | |
9883 | ||
9884 | static int | |
9885 | perf_event_set_addr_filter(struct perf_event *event, char *filter_str) | |
9886 | { | |
9887 | LIST_HEAD(filters); | |
9888 | int ret; | |
9889 | ||
9890 | /* | |
9891 | * Since this is called in perf_ioctl() path, we're already holding | |
9892 | * ctx::mutex. | |
9893 | */ | |
9894 | lockdep_assert_held(&event->ctx->mutex); | |
9895 | ||
9896 | if (WARN_ON_ONCE(event->parent)) | |
9897 | return -EINVAL; | |
9898 | ||
375637bc AS |
9899 | ret = perf_event_parse_addr_filter(event, filter_str, &filters); |
9900 | if (ret) | |
6ce77bfd | 9901 | goto fail_clear_files; |
375637bc AS |
9902 | |
9903 | ret = event->pmu->addr_filters_validate(&filters); | |
6ce77bfd AS |
9904 | if (ret) |
9905 | goto fail_free_filters; | |
375637bc AS |
9906 | |
9907 | /* remove existing filters, if any */ | |
9908 | perf_addr_filters_splice(event, &filters); | |
9909 | ||
9910 | /* install new filters */ | |
9911 | perf_event_for_each_child(event, perf_event_addr_filters_apply); | |
9912 | ||
6ce77bfd AS |
9913 | return ret; |
9914 | ||
9915 | fail_free_filters: | |
9916 | free_filters_list(&filters); | |
9917 | ||
9918 | fail_clear_files: | |
9919 | event->addr_filters.nr_file_filters = 0; | |
9920 | ||
375637bc AS |
9921 | return ret; |
9922 | } | |
9923 | ||
c796bbbe AS |
9924 | static int perf_event_set_filter(struct perf_event *event, void __user *arg) |
9925 | { | |
c796bbbe | 9926 | int ret = -EINVAL; |
e12f03d7 | 9927 | char *filter_str; |
c796bbbe AS |
9928 | |
9929 | filter_str = strndup_user(arg, PAGE_SIZE); | |
9930 | if (IS_ERR(filter_str)) | |
9931 | return PTR_ERR(filter_str); | |
9932 | ||
e12f03d7 SL |
9933 | #ifdef CONFIG_EVENT_TRACING |
9934 | if (perf_event_is_tracing(event)) { | |
9935 | struct perf_event_context *ctx = event->ctx; | |
9936 | ||
9937 | /* | |
9938 | * Beware, here be dragons!! | |
9939 | * | |
9940 | * the tracepoint muck will deadlock against ctx->mutex, but | |
9941 | * the tracepoint stuff does not actually need it. So | |
9942 | * temporarily drop ctx->mutex. As per perf_event_ctx_lock() we | |
9943 | * already have a reference on ctx. | |
9944 | * | |
9945 | * This can result in event getting moved to a different ctx, | |
9946 | * but that does not affect the tracepoint state. | |
9947 | */ | |
9948 | mutex_unlock(&ctx->mutex); | |
9949 | ret = ftrace_profile_set_filter(event, event->attr.config, filter_str); | |
9950 | mutex_lock(&ctx->mutex); | |
9951 | } else | |
9952 | #endif | |
9953 | if (has_addr_filter(event)) | |
375637bc | 9954 | ret = perf_event_set_addr_filter(event, filter_str); |
c796bbbe AS |
9955 | |
9956 | kfree(filter_str); | |
9957 | return ret; | |
9958 | } | |
9959 | ||
b0a873eb PZ |
9960 | /* |
9961 | * hrtimer based swevent callback | |
9962 | */ | |
f29ac756 | 9963 | |
b0a873eb | 9964 | static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer) |
f29ac756 | 9965 | { |
b0a873eb PZ |
9966 | enum hrtimer_restart ret = HRTIMER_RESTART; |
9967 | struct perf_sample_data data; | |
9968 | struct pt_regs *regs; | |
9969 | struct perf_event *event; | |
9970 | u64 period; | |
f29ac756 | 9971 | |
b0a873eb | 9972 | event = container_of(hrtimer, struct perf_event, hw.hrtimer); |
ba3dd36c PZ |
9973 | |
9974 | if (event->state != PERF_EVENT_STATE_ACTIVE) | |
9975 | return HRTIMER_NORESTART; | |
9976 | ||
b0a873eb | 9977 | event->pmu->read(event); |
f344011c | 9978 | |
fd0d000b | 9979 | perf_sample_data_init(&data, 0, event->hw.last_period); |
b0a873eb PZ |
9980 | regs = get_irq_regs(); |
9981 | ||
9982 | if (regs && !perf_exclude_event(event, regs)) { | |
77aeeebd | 9983 | if (!(event->attr.exclude_idle && is_idle_task(current))) |
33b07b8b | 9984 | if (__perf_event_overflow(event, 1, &data, regs)) |
b0a873eb PZ |
9985 | ret = HRTIMER_NORESTART; |
9986 | } | |
24f1e32c | 9987 | |
b0a873eb PZ |
9988 | period = max_t(u64, 10000, event->hw.sample_period); |
9989 | hrtimer_forward_now(hrtimer, ns_to_ktime(period)); | |
24f1e32c | 9990 | |
b0a873eb | 9991 | return ret; |
f29ac756 PZ |
9992 | } |
9993 | ||
b0a873eb | 9994 | static void perf_swevent_start_hrtimer(struct perf_event *event) |
5c92d124 | 9995 | { |
b0a873eb | 9996 | struct hw_perf_event *hwc = &event->hw; |
5d508e82 FBH |
9997 | s64 period; |
9998 | ||
9999 | if (!is_sampling_event(event)) | |
10000 | return; | |
f5ffe02e | 10001 | |
5d508e82 FBH |
10002 | period = local64_read(&hwc->period_left); |
10003 | if (period) { | |
10004 | if (period < 0) | |
10005 | period = 10000; | |
fa407f35 | 10006 | |
5d508e82 FBH |
10007 | local64_set(&hwc->period_left, 0); |
10008 | } else { | |
10009 | period = max_t(u64, 10000, hwc->sample_period); | |
10010 | } | |
3497d206 | 10011 | hrtimer_start(&hwc->hrtimer, ns_to_ktime(period), |
30f9028b | 10012 | HRTIMER_MODE_REL_PINNED_HARD); |
24f1e32c | 10013 | } |
b0a873eb PZ |
10014 | |
10015 | static void perf_swevent_cancel_hrtimer(struct perf_event *event) | |
24f1e32c | 10016 | { |
b0a873eb PZ |
10017 | struct hw_perf_event *hwc = &event->hw; |
10018 | ||
6c7e550f | 10019 | if (is_sampling_event(event)) { |
b0a873eb | 10020 | ktime_t remaining = hrtimer_get_remaining(&hwc->hrtimer); |
fa407f35 | 10021 | local64_set(&hwc->period_left, ktime_to_ns(remaining)); |
b0a873eb PZ |
10022 | |
10023 | hrtimer_cancel(&hwc->hrtimer); | |
10024 | } | |
24f1e32c FW |
10025 | } |
10026 | ||
ba3dd36c PZ |
10027 | static void perf_swevent_init_hrtimer(struct perf_event *event) |
10028 | { | |
10029 | struct hw_perf_event *hwc = &event->hw; | |
10030 | ||
10031 | if (!is_sampling_event(event)) | |
10032 | return; | |
10033 | ||
30f9028b | 10034 | hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_HARD); |
ba3dd36c PZ |
10035 | hwc->hrtimer.function = perf_swevent_hrtimer; |
10036 | ||
10037 | /* | |
10038 | * Since hrtimers have a fixed rate, we can do a static freq->period | |
10039 | * mapping and avoid the whole period adjust feedback stuff. | |
10040 | */ | |
10041 | if (event->attr.freq) { | |
10042 | long freq = event->attr.sample_freq; | |
10043 | ||
10044 | event->attr.sample_period = NSEC_PER_SEC / freq; | |
10045 | hwc->sample_period = event->attr.sample_period; | |
10046 | local64_set(&hwc->period_left, hwc->sample_period); | |
778141e3 | 10047 | hwc->last_period = hwc->sample_period; |
ba3dd36c PZ |
10048 | event->attr.freq = 0; |
10049 | } | |
10050 | } | |
10051 | ||
b0a873eb PZ |
10052 | /* |
10053 | * Software event: cpu wall time clock | |
10054 | */ | |
10055 | ||
10056 | static void cpu_clock_event_update(struct perf_event *event) | |
24f1e32c | 10057 | { |
b0a873eb PZ |
10058 | s64 prev; |
10059 | u64 now; | |
10060 | ||
a4eaf7f1 | 10061 | now = local_clock(); |
b0a873eb PZ |
10062 | prev = local64_xchg(&event->hw.prev_count, now); |
10063 | local64_add(now - prev, &event->count); | |
24f1e32c | 10064 | } |
24f1e32c | 10065 | |
a4eaf7f1 | 10066 | static void cpu_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 10067 | { |
a4eaf7f1 | 10068 | local64_set(&event->hw.prev_count, local_clock()); |
b0a873eb | 10069 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
10070 | } |
10071 | ||
a4eaf7f1 | 10072 | static void cpu_clock_event_stop(struct perf_event *event, int flags) |
f29ac756 | 10073 | { |
b0a873eb PZ |
10074 | perf_swevent_cancel_hrtimer(event); |
10075 | cpu_clock_event_update(event); | |
10076 | } | |
f29ac756 | 10077 | |
a4eaf7f1 PZ |
10078 | static int cpu_clock_event_add(struct perf_event *event, int flags) |
10079 | { | |
10080 | if (flags & PERF_EF_START) | |
10081 | cpu_clock_event_start(event, flags); | |
6a694a60 | 10082 | perf_event_update_userpage(event); |
a4eaf7f1 PZ |
10083 | |
10084 | return 0; | |
10085 | } | |
10086 | ||
10087 | static void cpu_clock_event_del(struct perf_event *event, int flags) | |
10088 | { | |
10089 | cpu_clock_event_stop(event, flags); | |
10090 | } | |
10091 | ||
b0a873eb PZ |
10092 | static void cpu_clock_event_read(struct perf_event *event) |
10093 | { | |
10094 | cpu_clock_event_update(event); | |
10095 | } | |
f344011c | 10096 | |
b0a873eb PZ |
10097 | static int cpu_clock_event_init(struct perf_event *event) |
10098 | { | |
10099 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
10100 | return -ENOENT; | |
10101 | ||
10102 | if (event->attr.config != PERF_COUNT_SW_CPU_CLOCK) | |
10103 | return -ENOENT; | |
10104 | ||
2481c5fa SE |
10105 | /* |
10106 | * no branch sampling for software events | |
10107 | */ | |
10108 | if (has_branch_stack(event)) | |
10109 | return -EOPNOTSUPP; | |
10110 | ||
ba3dd36c PZ |
10111 | perf_swevent_init_hrtimer(event); |
10112 | ||
b0a873eb | 10113 | return 0; |
f29ac756 PZ |
10114 | } |
10115 | ||
b0a873eb | 10116 | static struct pmu perf_cpu_clock = { |
89a1e187 PZ |
10117 | .task_ctx_nr = perf_sw_context, |
10118 | ||
34f43927 PZ |
10119 | .capabilities = PERF_PMU_CAP_NO_NMI, |
10120 | ||
b0a873eb | 10121 | .event_init = cpu_clock_event_init, |
a4eaf7f1 PZ |
10122 | .add = cpu_clock_event_add, |
10123 | .del = cpu_clock_event_del, | |
10124 | .start = cpu_clock_event_start, | |
10125 | .stop = cpu_clock_event_stop, | |
b0a873eb PZ |
10126 | .read = cpu_clock_event_read, |
10127 | }; | |
10128 | ||
10129 | /* | |
10130 | * Software event: task time clock | |
10131 | */ | |
10132 | ||
10133 | static void task_clock_event_update(struct perf_event *event, u64 now) | |
5c92d124 | 10134 | { |
b0a873eb PZ |
10135 | u64 prev; |
10136 | s64 delta; | |
5c92d124 | 10137 | |
b0a873eb PZ |
10138 | prev = local64_xchg(&event->hw.prev_count, now); |
10139 | delta = now - prev; | |
10140 | local64_add(delta, &event->count); | |
10141 | } | |
5c92d124 | 10142 | |
a4eaf7f1 | 10143 | static void task_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 10144 | { |
a4eaf7f1 | 10145 | local64_set(&event->hw.prev_count, event->ctx->time); |
b0a873eb | 10146 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
10147 | } |
10148 | ||
a4eaf7f1 | 10149 | static void task_clock_event_stop(struct perf_event *event, int flags) |
b0a873eb PZ |
10150 | { |
10151 | perf_swevent_cancel_hrtimer(event); | |
10152 | task_clock_event_update(event, event->ctx->time); | |
a4eaf7f1 PZ |
10153 | } |
10154 | ||
10155 | static int task_clock_event_add(struct perf_event *event, int flags) | |
10156 | { | |
10157 | if (flags & PERF_EF_START) | |
10158 | task_clock_event_start(event, flags); | |
6a694a60 | 10159 | perf_event_update_userpage(event); |
b0a873eb | 10160 | |
a4eaf7f1 PZ |
10161 | return 0; |
10162 | } | |
10163 | ||
10164 | static void task_clock_event_del(struct perf_event *event, int flags) | |
10165 | { | |
10166 | task_clock_event_stop(event, PERF_EF_UPDATE); | |
b0a873eb PZ |
10167 | } |
10168 | ||
10169 | static void task_clock_event_read(struct perf_event *event) | |
10170 | { | |
768a06e2 PZ |
10171 | u64 now = perf_clock(); |
10172 | u64 delta = now - event->ctx->timestamp; | |
10173 | u64 time = event->ctx->time + delta; | |
b0a873eb PZ |
10174 | |
10175 | task_clock_event_update(event, time); | |
10176 | } | |
10177 | ||
10178 | static int task_clock_event_init(struct perf_event *event) | |
6fb2915d | 10179 | { |
b0a873eb PZ |
10180 | if (event->attr.type != PERF_TYPE_SOFTWARE) |
10181 | return -ENOENT; | |
10182 | ||
10183 | if (event->attr.config != PERF_COUNT_SW_TASK_CLOCK) | |
10184 | return -ENOENT; | |
10185 | ||
2481c5fa SE |
10186 | /* |
10187 | * no branch sampling for software events | |
10188 | */ | |
10189 | if (has_branch_stack(event)) | |
10190 | return -EOPNOTSUPP; | |
10191 | ||
ba3dd36c PZ |
10192 | perf_swevent_init_hrtimer(event); |
10193 | ||
b0a873eb | 10194 | return 0; |
6fb2915d LZ |
10195 | } |
10196 | ||
b0a873eb | 10197 | static struct pmu perf_task_clock = { |
89a1e187 PZ |
10198 | .task_ctx_nr = perf_sw_context, |
10199 | ||
34f43927 PZ |
10200 | .capabilities = PERF_PMU_CAP_NO_NMI, |
10201 | ||
b0a873eb | 10202 | .event_init = task_clock_event_init, |
a4eaf7f1 PZ |
10203 | .add = task_clock_event_add, |
10204 | .del = task_clock_event_del, | |
10205 | .start = task_clock_event_start, | |
10206 | .stop = task_clock_event_stop, | |
b0a873eb PZ |
10207 | .read = task_clock_event_read, |
10208 | }; | |
6fb2915d | 10209 | |
ad5133b7 | 10210 | static void perf_pmu_nop_void(struct pmu *pmu) |
e077df4f | 10211 | { |
e077df4f | 10212 | } |
6fb2915d | 10213 | |
fbbe0701 SB |
10214 | static void perf_pmu_nop_txn(struct pmu *pmu, unsigned int flags) |
10215 | { | |
10216 | } | |
10217 | ||
ad5133b7 | 10218 | static int perf_pmu_nop_int(struct pmu *pmu) |
6fb2915d | 10219 | { |
ad5133b7 | 10220 | return 0; |
6fb2915d LZ |
10221 | } |
10222 | ||
81ec3f3c JO |
10223 | static int perf_event_nop_int(struct perf_event *event, u64 value) |
10224 | { | |
10225 | return 0; | |
10226 | } | |
10227 | ||
18ab2cd3 | 10228 | static DEFINE_PER_CPU(unsigned int, nop_txn_flags); |
fbbe0701 SB |
10229 | |
10230 | static void perf_pmu_start_txn(struct pmu *pmu, unsigned int flags) | |
6fb2915d | 10231 | { |
fbbe0701 SB |
10232 | __this_cpu_write(nop_txn_flags, flags); |
10233 | ||
10234 | if (flags & ~PERF_PMU_TXN_ADD) | |
10235 | return; | |
10236 | ||
ad5133b7 | 10237 | perf_pmu_disable(pmu); |
6fb2915d LZ |
10238 | } |
10239 | ||
ad5133b7 PZ |
10240 | static int perf_pmu_commit_txn(struct pmu *pmu) |
10241 | { | |
fbbe0701 SB |
10242 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
10243 | ||
10244 | __this_cpu_write(nop_txn_flags, 0); | |
10245 | ||
10246 | if (flags & ~PERF_PMU_TXN_ADD) | |
10247 | return 0; | |
10248 | ||
ad5133b7 PZ |
10249 | perf_pmu_enable(pmu); |
10250 | return 0; | |
10251 | } | |
e077df4f | 10252 | |
ad5133b7 | 10253 | static void perf_pmu_cancel_txn(struct pmu *pmu) |
24f1e32c | 10254 | { |
fbbe0701 SB |
10255 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
10256 | ||
10257 | __this_cpu_write(nop_txn_flags, 0); | |
10258 | ||
10259 | if (flags & ~PERF_PMU_TXN_ADD) | |
10260 | return; | |
10261 | ||
ad5133b7 | 10262 | perf_pmu_enable(pmu); |
24f1e32c FW |
10263 | } |
10264 | ||
35edc2a5 PZ |
10265 | static int perf_event_idx_default(struct perf_event *event) |
10266 | { | |
c719f560 | 10267 | return 0; |
35edc2a5 PZ |
10268 | } |
10269 | ||
8dc85d54 PZ |
10270 | /* |
10271 | * Ensures all contexts with the same task_ctx_nr have the same | |
10272 | * pmu_cpu_context too. | |
10273 | */ | |
9e317041 | 10274 | static struct perf_cpu_context __percpu *find_pmu_context(int ctxn) |
24f1e32c | 10275 | { |
8dc85d54 | 10276 | struct pmu *pmu; |
b326e956 | 10277 | |
8dc85d54 PZ |
10278 | if (ctxn < 0) |
10279 | return NULL; | |
24f1e32c | 10280 | |
8dc85d54 PZ |
10281 | list_for_each_entry(pmu, &pmus, entry) { |
10282 | if (pmu->task_ctx_nr == ctxn) | |
10283 | return pmu->pmu_cpu_context; | |
10284 | } | |
24f1e32c | 10285 | |
8dc85d54 | 10286 | return NULL; |
24f1e32c FW |
10287 | } |
10288 | ||
51676957 PZ |
10289 | static void free_pmu_context(struct pmu *pmu) |
10290 | { | |
df0062b2 WD |
10291 | /* |
10292 | * Static contexts such as perf_sw_context have a global lifetime | |
10293 | * and may be shared between different PMUs. Avoid freeing them | |
10294 | * when a single PMU is going away. | |
10295 | */ | |
10296 | if (pmu->task_ctx_nr > perf_invalid_context) | |
10297 | return; | |
10298 | ||
51676957 | 10299 | free_percpu(pmu->pmu_cpu_context); |
24f1e32c | 10300 | } |
6e855cd4 AS |
10301 | |
10302 | /* | |
10303 | * Let userspace know that this PMU supports address range filtering: | |
10304 | */ | |
10305 | static ssize_t nr_addr_filters_show(struct device *dev, | |
10306 | struct device_attribute *attr, | |
10307 | char *page) | |
10308 | { | |
10309 | struct pmu *pmu = dev_get_drvdata(dev); | |
10310 | ||
10311 | return snprintf(page, PAGE_SIZE - 1, "%d\n", pmu->nr_addr_filters); | |
10312 | } | |
10313 | DEVICE_ATTR_RO(nr_addr_filters); | |
10314 | ||
2e80a82a | 10315 | static struct idr pmu_idr; |
d6d020e9 | 10316 | |
abe43400 PZ |
10317 | static ssize_t |
10318 | type_show(struct device *dev, struct device_attribute *attr, char *page) | |
10319 | { | |
10320 | struct pmu *pmu = dev_get_drvdata(dev); | |
10321 | ||
10322 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->type); | |
10323 | } | |
90826ca7 | 10324 | static DEVICE_ATTR_RO(type); |
abe43400 | 10325 | |
62b85639 SE |
10326 | static ssize_t |
10327 | perf_event_mux_interval_ms_show(struct device *dev, | |
10328 | struct device_attribute *attr, | |
10329 | char *page) | |
10330 | { | |
10331 | struct pmu *pmu = dev_get_drvdata(dev); | |
10332 | ||
10333 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->hrtimer_interval_ms); | |
10334 | } | |
10335 | ||
272325c4 PZ |
10336 | static DEFINE_MUTEX(mux_interval_mutex); |
10337 | ||
62b85639 SE |
10338 | static ssize_t |
10339 | perf_event_mux_interval_ms_store(struct device *dev, | |
10340 | struct device_attribute *attr, | |
10341 | const char *buf, size_t count) | |
10342 | { | |
10343 | struct pmu *pmu = dev_get_drvdata(dev); | |
10344 | int timer, cpu, ret; | |
10345 | ||
10346 | ret = kstrtoint(buf, 0, &timer); | |
10347 | if (ret) | |
10348 | return ret; | |
10349 | ||
10350 | if (timer < 1) | |
10351 | return -EINVAL; | |
10352 | ||
10353 | /* same value, noting to do */ | |
10354 | if (timer == pmu->hrtimer_interval_ms) | |
10355 | return count; | |
10356 | ||
272325c4 | 10357 | mutex_lock(&mux_interval_mutex); |
62b85639 SE |
10358 | pmu->hrtimer_interval_ms = timer; |
10359 | ||
10360 | /* update all cpuctx for this PMU */ | |
a63fbed7 | 10361 | cpus_read_lock(); |
272325c4 | 10362 | for_each_online_cpu(cpu) { |
62b85639 SE |
10363 | struct perf_cpu_context *cpuctx; |
10364 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
10365 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * timer); | |
10366 | ||
272325c4 PZ |
10367 | cpu_function_call(cpu, |
10368 | (remote_function_f)perf_mux_hrtimer_restart, cpuctx); | |
62b85639 | 10369 | } |
a63fbed7 | 10370 | cpus_read_unlock(); |
272325c4 | 10371 | mutex_unlock(&mux_interval_mutex); |
62b85639 SE |
10372 | |
10373 | return count; | |
10374 | } | |
90826ca7 | 10375 | static DEVICE_ATTR_RW(perf_event_mux_interval_ms); |
62b85639 | 10376 | |
90826ca7 GKH |
10377 | static struct attribute *pmu_dev_attrs[] = { |
10378 | &dev_attr_type.attr, | |
10379 | &dev_attr_perf_event_mux_interval_ms.attr, | |
10380 | NULL, | |
abe43400 | 10381 | }; |
90826ca7 | 10382 | ATTRIBUTE_GROUPS(pmu_dev); |
abe43400 PZ |
10383 | |
10384 | static int pmu_bus_running; | |
10385 | static struct bus_type pmu_bus = { | |
10386 | .name = "event_source", | |
90826ca7 | 10387 | .dev_groups = pmu_dev_groups, |
abe43400 PZ |
10388 | }; |
10389 | ||
10390 | static void pmu_dev_release(struct device *dev) | |
10391 | { | |
10392 | kfree(dev); | |
10393 | } | |
10394 | ||
10395 | static int pmu_dev_alloc(struct pmu *pmu) | |
10396 | { | |
10397 | int ret = -ENOMEM; | |
10398 | ||
10399 | pmu->dev = kzalloc(sizeof(struct device), GFP_KERNEL); | |
10400 | if (!pmu->dev) | |
10401 | goto out; | |
10402 | ||
0c9d42ed | 10403 | pmu->dev->groups = pmu->attr_groups; |
abe43400 PZ |
10404 | device_initialize(pmu->dev); |
10405 | ret = dev_set_name(pmu->dev, "%s", pmu->name); | |
10406 | if (ret) | |
10407 | goto free_dev; | |
10408 | ||
10409 | dev_set_drvdata(pmu->dev, pmu); | |
10410 | pmu->dev->bus = &pmu_bus; | |
10411 | pmu->dev->release = pmu_dev_release; | |
10412 | ret = device_add(pmu->dev); | |
10413 | if (ret) | |
10414 | goto free_dev; | |
10415 | ||
6e855cd4 AS |
10416 | /* For PMUs with address filters, throw in an extra attribute: */ |
10417 | if (pmu->nr_addr_filters) | |
10418 | ret = device_create_file(pmu->dev, &dev_attr_nr_addr_filters); | |
10419 | ||
10420 | if (ret) | |
10421 | goto del_dev; | |
10422 | ||
f3a3a825 JO |
10423 | if (pmu->attr_update) |
10424 | ret = sysfs_update_groups(&pmu->dev->kobj, pmu->attr_update); | |
10425 | ||
10426 | if (ret) | |
10427 | goto del_dev; | |
10428 | ||
abe43400 PZ |
10429 | out: |
10430 | return ret; | |
10431 | ||
6e855cd4 AS |
10432 | del_dev: |
10433 | device_del(pmu->dev); | |
10434 | ||
abe43400 PZ |
10435 | free_dev: |
10436 | put_device(pmu->dev); | |
10437 | goto out; | |
10438 | } | |
10439 | ||
547e9fd7 | 10440 | static struct lock_class_key cpuctx_mutex; |
facc4307 | 10441 | static struct lock_class_key cpuctx_lock; |
547e9fd7 | 10442 | |
03d8e80b | 10443 | int perf_pmu_register(struct pmu *pmu, const char *name, int type) |
24f1e32c | 10444 | { |
66d258c5 | 10445 | int cpu, ret, max = PERF_TYPE_MAX; |
24f1e32c | 10446 | |
b0a873eb | 10447 | mutex_lock(&pmus_lock); |
33696fc0 PZ |
10448 | ret = -ENOMEM; |
10449 | pmu->pmu_disable_count = alloc_percpu(int); | |
10450 | if (!pmu->pmu_disable_count) | |
10451 | goto unlock; | |
f29ac756 | 10452 | |
2e80a82a PZ |
10453 | pmu->type = -1; |
10454 | if (!name) | |
10455 | goto skip_type; | |
10456 | pmu->name = name; | |
10457 | ||
66d258c5 PZ |
10458 | if (type != PERF_TYPE_SOFTWARE) { |
10459 | if (type >= 0) | |
10460 | max = type; | |
10461 | ||
10462 | ret = idr_alloc(&pmu_idr, pmu, max, 0, GFP_KERNEL); | |
10463 | if (ret < 0) | |
2e80a82a | 10464 | goto free_pdc; |
66d258c5 PZ |
10465 | |
10466 | WARN_ON(type >= 0 && ret != type); | |
10467 | ||
10468 | type = ret; | |
2e80a82a PZ |
10469 | } |
10470 | pmu->type = type; | |
10471 | ||
abe43400 PZ |
10472 | if (pmu_bus_running) { |
10473 | ret = pmu_dev_alloc(pmu); | |
10474 | if (ret) | |
10475 | goto free_idr; | |
10476 | } | |
10477 | ||
2e80a82a | 10478 | skip_type: |
26657848 PZ |
10479 | if (pmu->task_ctx_nr == perf_hw_context) { |
10480 | static int hw_context_taken = 0; | |
10481 | ||
5101ef20 MR |
10482 | /* |
10483 | * Other than systems with heterogeneous CPUs, it never makes | |
10484 | * sense for two PMUs to share perf_hw_context. PMUs which are | |
10485 | * uncore must use perf_invalid_context. | |
10486 | */ | |
10487 | if (WARN_ON_ONCE(hw_context_taken && | |
10488 | !(pmu->capabilities & PERF_PMU_CAP_HETEROGENEOUS_CPUS))) | |
26657848 PZ |
10489 | pmu->task_ctx_nr = perf_invalid_context; |
10490 | ||
10491 | hw_context_taken = 1; | |
10492 | } | |
10493 | ||
8dc85d54 PZ |
10494 | pmu->pmu_cpu_context = find_pmu_context(pmu->task_ctx_nr); |
10495 | if (pmu->pmu_cpu_context) | |
10496 | goto got_cpu_context; | |
f29ac756 | 10497 | |
c4814202 | 10498 | ret = -ENOMEM; |
108b02cf PZ |
10499 | pmu->pmu_cpu_context = alloc_percpu(struct perf_cpu_context); |
10500 | if (!pmu->pmu_cpu_context) | |
abe43400 | 10501 | goto free_dev; |
f344011c | 10502 | |
108b02cf PZ |
10503 | for_each_possible_cpu(cpu) { |
10504 | struct perf_cpu_context *cpuctx; | |
10505 | ||
10506 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
eb184479 | 10507 | __perf_event_init_context(&cpuctx->ctx); |
547e9fd7 | 10508 | lockdep_set_class(&cpuctx->ctx.mutex, &cpuctx_mutex); |
facc4307 | 10509 | lockdep_set_class(&cpuctx->ctx.lock, &cpuctx_lock); |
108b02cf | 10510 | cpuctx->ctx.pmu = pmu; |
a63fbed7 | 10511 | cpuctx->online = cpumask_test_cpu(cpu, perf_online_mask); |
9e630205 | 10512 | |
272325c4 | 10513 | __perf_mux_hrtimer_init(cpuctx, cpu); |
836196be IR |
10514 | |
10515 | cpuctx->heap_size = ARRAY_SIZE(cpuctx->heap_default); | |
10516 | cpuctx->heap = cpuctx->heap_default; | |
108b02cf | 10517 | } |
76e1d904 | 10518 | |
8dc85d54 | 10519 | got_cpu_context: |
ad5133b7 PZ |
10520 | if (!pmu->start_txn) { |
10521 | if (pmu->pmu_enable) { | |
10522 | /* | |
10523 | * If we have pmu_enable/pmu_disable calls, install | |
10524 | * transaction stubs that use that to try and batch | |
10525 | * hardware accesses. | |
10526 | */ | |
10527 | pmu->start_txn = perf_pmu_start_txn; | |
10528 | pmu->commit_txn = perf_pmu_commit_txn; | |
10529 | pmu->cancel_txn = perf_pmu_cancel_txn; | |
10530 | } else { | |
fbbe0701 | 10531 | pmu->start_txn = perf_pmu_nop_txn; |
ad5133b7 PZ |
10532 | pmu->commit_txn = perf_pmu_nop_int; |
10533 | pmu->cancel_txn = perf_pmu_nop_void; | |
f344011c | 10534 | } |
5c92d124 | 10535 | } |
15dbf27c | 10536 | |
ad5133b7 PZ |
10537 | if (!pmu->pmu_enable) { |
10538 | pmu->pmu_enable = perf_pmu_nop_void; | |
10539 | pmu->pmu_disable = perf_pmu_nop_void; | |
10540 | } | |
10541 | ||
81ec3f3c JO |
10542 | if (!pmu->check_period) |
10543 | pmu->check_period = perf_event_nop_int; | |
10544 | ||
35edc2a5 PZ |
10545 | if (!pmu->event_idx) |
10546 | pmu->event_idx = perf_event_idx_default; | |
10547 | ||
d44f821b LK |
10548 | /* |
10549 | * Ensure the TYPE_SOFTWARE PMUs are at the head of the list, | |
10550 | * since these cannot be in the IDR. This way the linear search | |
10551 | * is fast, provided a valid software event is provided. | |
10552 | */ | |
10553 | if (type == PERF_TYPE_SOFTWARE || !name) | |
10554 | list_add_rcu(&pmu->entry, &pmus); | |
10555 | else | |
10556 | list_add_tail_rcu(&pmu->entry, &pmus); | |
10557 | ||
bed5b25a | 10558 | atomic_set(&pmu->exclusive_cnt, 0); |
33696fc0 PZ |
10559 | ret = 0; |
10560 | unlock: | |
b0a873eb PZ |
10561 | mutex_unlock(&pmus_lock); |
10562 | ||
33696fc0 | 10563 | return ret; |
108b02cf | 10564 | |
abe43400 PZ |
10565 | free_dev: |
10566 | device_del(pmu->dev); | |
10567 | put_device(pmu->dev); | |
10568 | ||
2e80a82a | 10569 | free_idr: |
66d258c5 | 10570 | if (pmu->type != PERF_TYPE_SOFTWARE) |
2e80a82a PZ |
10571 | idr_remove(&pmu_idr, pmu->type); |
10572 | ||
108b02cf PZ |
10573 | free_pdc: |
10574 | free_percpu(pmu->pmu_disable_count); | |
10575 | goto unlock; | |
f29ac756 | 10576 | } |
c464c76e | 10577 | EXPORT_SYMBOL_GPL(perf_pmu_register); |
f29ac756 | 10578 | |
b0a873eb | 10579 | void perf_pmu_unregister(struct pmu *pmu) |
5c92d124 | 10580 | { |
b0a873eb PZ |
10581 | mutex_lock(&pmus_lock); |
10582 | list_del_rcu(&pmu->entry); | |
5c92d124 | 10583 | |
0475f9ea | 10584 | /* |
cde8e884 PZ |
10585 | * We dereference the pmu list under both SRCU and regular RCU, so |
10586 | * synchronize against both of those. | |
0475f9ea | 10587 | */ |
b0a873eb | 10588 | synchronize_srcu(&pmus_srcu); |
cde8e884 | 10589 | synchronize_rcu(); |
d6d020e9 | 10590 | |
33696fc0 | 10591 | free_percpu(pmu->pmu_disable_count); |
66d258c5 | 10592 | if (pmu->type != PERF_TYPE_SOFTWARE) |
2e80a82a | 10593 | idr_remove(&pmu_idr, pmu->type); |
a9f97721 | 10594 | if (pmu_bus_running) { |
0933840a JO |
10595 | if (pmu->nr_addr_filters) |
10596 | device_remove_file(pmu->dev, &dev_attr_nr_addr_filters); | |
10597 | device_del(pmu->dev); | |
10598 | put_device(pmu->dev); | |
10599 | } | |
51676957 | 10600 | free_pmu_context(pmu); |
a9f97721 | 10601 | mutex_unlock(&pmus_lock); |
b0a873eb | 10602 | } |
c464c76e | 10603 | EXPORT_SYMBOL_GPL(perf_pmu_unregister); |
d6d020e9 | 10604 | |
e321d02d KL |
10605 | static inline bool has_extended_regs(struct perf_event *event) |
10606 | { | |
10607 | return (event->attr.sample_regs_user & PERF_REG_EXTENDED_MASK) || | |
10608 | (event->attr.sample_regs_intr & PERF_REG_EXTENDED_MASK); | |
10609 | } | |
10610 | ||
cc34b98b MR |
10611 | static int perf_try_init_event(struct pmu *pmu, struct perf_event *event) |
10612 | { | |
ccd41c86 | 10613 | struct perf_event_context *ctx = NULL; |
cc34b98b MR |
10614 | int ret; |
10615 | ||
10616 | if (!try_module_get(pmu->module)) | |
10617 | return -ENODEV; | |
ccd41c86 | 10618 | |
0c7296ca PZ |
10619 | /* |
10620 | * A number of pmu->event_init() methods iterate the sibling_list to, | |
10621 | * for example, validate if the group fits on the PMU. Therefore, | |
10622 | * if this is a sibling event, acquire the ctx->mutex to protect | |
10623 | * the sibling_list. | |
10624 | */ | |
10625 | if (event->group_leader != event && pmu->task_ctx_nr != perf_sw_context) { | |
8b10c5e2 PZ |
10626 | /* |
10627 | * This ctx->mutex can nest when we're called through | |
10628 | * inheritance. See the perf_event_ctx_lock_nested() comment. | |
10629 | */ | |
10630 | ctx = perf_event_ctx_lock_nested(event->group_leader, | |
10631 | SINGLE_DEPTH_NESTING); | |
ccd41c86 PZ |
10632 | BUG_ON(!ctx); |
10633 | } | |
10634 | ||
cc34b98b MR |
10635 | event->pmu = pmu; |
10636 | ret = pmu->event_init(event); | |
ccd41c86 PZ |
10637 | |
10638 | if (ctx) | |
10639 | perf_event_ctx_unlock(event->group_leader, ctx); | |
10640 | ||
cc6795ae | 10641 | if (!ret) { |
e321d02d KL |
10642 | if (!(pmu->capabilities & PERF_PMU_CAP_EXTENDED_REGS) && |
10643 | has_extended_regs(event)) | |
10644 | ret = -EOPNOTSUPP; | |
10645 | ||
cc6795ae | 10646 | if (pmu->capabilities & PERF_PMU_CAP_NO_EXCLUDE && |
e321d02d | 10647 | event_has_any_exclude_flag(event)) |
cc6795ae | 10648 | ret = -EINVAL; |
e321d02d KL |
10649 | |
10650 | if (ret && event->destroy) | |
10651 | event->destroy(event); | |
cc6795ae AM |
10652 | } |
10653 | ||
cc34b98b MR |
10654 | if (ret) |
10655 | module_put(pmu->module); | |
10656 | ||
10657 | return ret; | |
10658 | } | |
10659 | ||
18ab2cd3 | 10660 | static struct pmu *perf_init_event(struct perf_event *event) |
b0a873eb | 10661 | { |
66d258c5 | 10662 | int idx, type, ret; |
85c617ab | 10663 | struct pmu *pmu; |
b0a873eb PZ |
10664 | |
10665 | idx = srcu_read_lock(&pmus_srcu); | |
2e80a82a | 10666 | |
40999312 KL |
10667 | /* Try parent's PMU first: */ |
10668 | if (event->parent && event->parent->pmu) { | |
10669 | pmu = event->parent->pmu; | |
10670 | ret = perf_try_init_event(pmu, event); | |
10671 | if (!ret) | |
10672 | goto unlock; | |
10673 | } | |
10674 | ||
66d258c5 PZ |
10675 | /* |
10676 | * PERF_TYPE_HARDWARE and PERF_TYPE_HW_CACHE | |
10677 | * are often aliases for PERF_TYPE_RAW. | |
10678 | */ | |
10679 | type = event->attr.type; | |
10680 | if (type == PERF_TYPE_HARDWARE || type == PERF_TYPE_HW_CACHE) | |
10681 | type = PERF_TYPE_RAW; | |
10682 | ||
10683 | again: | |
2e80a82a | 10684 | rcu_read_lock(); |
66d258c5 | 10685 | pmu = idr_find(&pmu_idr, type); |
2e80a82a | 10686 | rcu_read_unlock(); |
940c5b29 | 10687 | if (pmu) { |
cc34b98b | 10688 | ret = perf_try_init_event(pmu, event); |
66d258c5 PZ |
10689 | if (ret == -ENOENT && event->attr.type != type) { |
10690 | type = event->attr.type; | |
10691 | goto again; | |
10692 | } | |
10693 | ||
940c5b29 LM |
10694 | if (ret) |
10695 | pmu = ERR_PTR(ret); | |
66d258c5 | 10696 | |
2e80a82a | 10697 | goto unlock; |
940c5b29 | 10698 | } |
2e80a82a | 10699 | |
9f0bff11 | 10700 | list_for_each_entry_rcu(pmu, &pmus, entry, lockdep_is_held(&pmus_srcu)) { |
cc34b98b | 10701 | ret = perf_try_init_event(pmu, event); |
b0a873eb | 10702 | if (!ret) |
e5f4d339 | 10703 | goto unlock; |
76e1d904 | 10704 | |
b0a873eb PZ |
10705 | if (ret != -ENOENT) { |
10706 | pmu = ERR_PTR(ret); | |
e5f4d339 | 10707 | goto unlock; |
f344011c | 10708 | } |
5c92d124 | 10709 | } |
e5f4d339 PZ |
10710 | pmu = ERR_PTR(-ENOENT); |
10711 | unlock: | |
b0a873eb | 10712 | srcu_read_unlock(&pmus_srcu, idx); |
15dbf27c | 10713 | |
4aeb0b42 | 10714 | return pmu; |
5c92d124 IM |
10715 | } |
10716 | ||
f2fb6bef KL |
10717 | static void attach_sb_event(struct perf_event *event) |
10718 | { | |
10719 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
10720 | ||
10721 | raw_spin_lock(&pel->lock); | |
10722 | list_add_rcu(&event->sb_list, &pel->list); | |
10723 | raw_spin_unlock(&pel->lock); | |
10724 | } | |
10725 | ||
aab5b71e PZ |
10726 | /* |
10727 | * We keep a list of all !task (and therefore per-cpu) events | |
10728 | * that need to receive side-band records. | |
10729 | * | |
10730 | * This avoids having to scan all the various PMU per-cpu contexts | |
10731 | * looking for them. | |
10732 | */ | |
f2fb6bef KL |
10733 | static void account_pmu_sb_event(struct perf_event *event) |
10734 | { | |
a4f144eb | 10735 | if (is_sb_event(event)) |
f2fb6bef KL |
10736 | attach_sb_event(event); |
10737 | } | |
10738 | ||
4beb31f3 FW |
10739 | static void account_event_cpu(struct perf_event *event, int cpu) |
10740 | { | |
10741 | if (event->parent) | |
10742 | return; | |
10743 | ||
4beb31f3 FW |
10744 | if (is_cgroup_event(event)) |
10745 | atomic_inc(&per_cpu(perf_cgroup_events, cpu)); | |
10746 | } | |
10747 | ||
555e0c1e FW |
10748 | /* Freq events need the tick to stay alive (see perf_event_task_tick). */ |
10749 | static void account_freq_event_nohz(void) | |
10750 | { | |
10751 | #ifdef CONFIG_NO_HZ_FULL | |
10752 | /* Lock so we don't race with concurrent unaccount */ | |
10753 | spin_lock(&nr_freq_lock); | |
10754 | if (atomic_inc_return(&nr_freq_events) == 1) | |
10755 | tick_nohz_dep_set(TICK_DEP_BIT_PERF_EVENTS); | |
10756 | spin_unlock(&nr_freq_lock); | |
10757 | #endif | |
10758 | } | |
10759 | ||
10760 | static void account_freq_event(void) | |
10761 | { | |
10762 | if (tick_nohz_full_enabled()) | |
10763 | account_freq_event_nohz(); | |
10764 | else | |
10765 | atomic_inc(&nr_freq_events); | |
10766 | } | |
10767 | ||
10768 | ||
766d6c07 FW |
10769 | static void account_event(struct perf_event *event) |
10770 | { | |
25432ae9 PZ |
10771 | bool inc = false; |
10772 | ||
4beb31f3 FW |
10773 | if (event->parent) |
10774 | return; | |
10775 | ||
766d6c07 | 10776 | if (event->attach_state & PERF_ATTACH_TASK) |
25432ae9 | 10777 | inc = true; |
766d6c07 FW |
10778 | if (event->attr.mmap || event->attr.mmap_data) |
10779 | atomic_inc(&nr_mmap_events); | |
10780 | if (event->attr.comm) | |
10781 | atomic_inc(&nr_comm_events); | |
e4222673 HB |
10782 | if (event->attr.namespaces) |
10783 | atomic_inc(&nr_namespaces_events); | |
766d6c07 FW |
10784 | if (event->attr.task) |
10785 | atomic_inc(&nr_task_events); | |
555e0c1e FW |
10786 | if (event->attr.freq) |
10787 | account_freq_event(); | |
45ac1403 AH |
10788 | if (event->attr.context_switch) { |
10789 | atomic_inc(&nr_switch_events); | |
25432ae9 | 10790 | inc = true; |
45ac1403 | 10791 | } |
4beb31f3 | 10792 | if (has_branch_stack(event)) |
25432ae9 | 10793 | inc = true; |
4beb31f3 | 10794 | if (is_cgroup_event(event)) |
25432ae9 | 10795 | inc = true; |
76193a94 SL |
10796 | if (event->attr.ksymbol) |
10797 | atomic_inc(&nr_ksymbol_events); | |
6ee52e2a SL |
10798 | if (event->attr.bpf_event) |
10799 | atomic_inc(&nr_bpf_events); | |
25432ae9 | 10800 | |
9107c89e | 10801 | if (inc) { |
5bce9db1 AS |
10802 | /* |
10803 | * We need the mutex here because static_branch_enable() | |
10804 | * must complete *before* the perf_sched_count increment | |
10805 | * becomes visible. | |
10806 | */ | |
9107c89e PZ |
10807 | if (atomic_inc_not_zero(&perf_sched_count)) |
10808 | goto enabled; | |
10809 | ||
10810 | mutex_lock(&perf_sched_mutex); | |
10811 | if (!atomic_read(&perf_sched_count)) { | |
10812 | static_branch_enable(&perf_sched_events); | |
10813 | /* | |
10814 | * Guarantee that all CPUs observe they key change and | |
10815 | * call the perf scheduling hooks before proceeding to | |
10816 | * install events that need them. | |
10817 | */ | |
0809d954 | 10818 | synchronize_rcu(); |
9107c89e PZ |
10819 | } |
10820 | /* | |
10821 | * Now that we have waited for the sync_sched(), allow further | |
10822 | * increments to by-pass the mutex. | |
10823 | */ | |
10824 | atomic_inc(&perf_sched_count); | |
10825 | mutex_unlock(&perf_sched_mutex); | |
10826 | } | |
10827 | enabled: | |
4beb31f3 FW |
10828 | |
10829 | account_event_cpu(event, event->cpu); | |
f2fb6bef KL |
10830 | |
10831 | account_pmu_sb_event(event); | |
766d6c07 FW |
10832 | } |
10833 | ||
0793a61d | 10834 | /* |
788faab7 | 10835 | * Allocate and initialize an event structure |
0793a61d | 10836 | */ |
cdd6c482 | 10837 | static struct perf_event * |
c3f00c70 | 10838 | perf_event_alloc(struct perf_event_attr *attr, int cpu, |
d580ff86 PZ |
10839 | struct task_struct *task, |
10840 | struct perf_event *group_leader, | |
10841 | struct perf_event *parent_event, | |
4dc0da86 | 10842 | perf_overflow_handler_t overflow_handler, |
79dff51e | 10843 | void *context, int cgroup_fd) |
0793a61d | 10844 | { |
51b0fe39 | 10845 | struct pmu *pmu; |
cdd6c482 IM |
10846 | struct perf_event *event; |
10847 | struct hw_perf_event *hwc; | |
90983b16 | 10848 | long err = -EINVAL; |
0793a61d | 10849 | |
66832eb4 ON |
10850 | if ((unsigned)cpu >= nr_cpu_ids) { |
10851 | if (!task || cpu != -1) | |
10852 | return ERR_PTR(-EINVAL); | |
10853 | } | |
10854 | ||
c3f00c70 | 10855 | event = kzalloc(sizeof(*event), GFP_KERNEL); |
cdd6c482 | 10856 | if (!event) |
d5d2bc0d | 10857 | return ERR_PTR(-ENOMEM); |
0793a61d | 10858 | |
04289bb9 | 10859 | /* |
cdd6c482 | 10860 | * Single events are their own group leaders, with an |
04289bb9 IM |
10861 | * empty sibling list: |
10862 | */ | |
10863 | if (!group_leader) | |
cdd6c482 | 10864 | group_leader = event; |
04289bb9 | 10865 | |
cdd6c482 IM |
10866 | mutex_init(&event->child_mutex); |
10867 | INIT_LIST_HEAD(&event->child_list); | |
fccc714b | 10868 | |
cdd6c482 IM |
10869 | INIT_LIST_HEAD(&event->event_entry); |
10870 | INIT_LIST_HEAD(&event->sibling_list); | |
6668128a | 10871 | INIT_LIST_HEAD(&event->active_list); |
8e1a2031 | 10872 | init_event_group(event); |
10c6db11 | 10873 | INIT_LIST_HEAD(&event->rb_entry); |
71ad88ef | 10874 | INIT_LIST_HEAD(&event->active_entry); |
375637bc | 10875 | INIT_LIST_HEAD(&event->addr_filters.list); |
f3ae75de SE |
10876 | INIT_HLIST_NODE(&event->hlist_entry); |
10877 | ||
10c6db11 | 10878 | |
cdd6c482 | 10879 | init_waitqueue_head(&event->waitq); |
1d54ad94 | 10880 | event->pending_disable = -1; |
e360adbe | 10881 | init_irq_work(&event->pending, perf_pending_event); |
0793a61d | 10882 | |
cdd6c482 | 10883 | mutex_init(&event->mmap_mutex); |
375637bc | 10884 | raw_spin_lock_init(&event->addr_filters.lock); |
7b732a75 | 10885 | |
a6fa941d | 10886 | atomic_long_set(&event->refcount, 1); |
cdd6c482 IM |
10887 | event->cpu = cpu; |
10888 | event->attr = *attr; | |
10889 | event->group_leader = group_leader; | |
10890 | event->pmu = NULL; | |
cdd6c482 | 10891 | event->oncpu = -1; |
a96bbc16 | 10892 | |
cdd6c482 | 10893 | event->parent = parent_event; |
b84fbc9f | 10894 | |
17cf22c3 | 10895 | event->ns = get_pid_ns(task_active_pid_ns(current)); |
cdd6c482 | 10896 | event->id = atomic64_inc_return(&perf_event_id); |
a96bbc16 | 10897 | |
cdd6c482 | 10898 | event->state = PERF_EVENT_STATE_INACTIVE; |
329d876d | 10899 | |
d580ff86 PZ |
10900 | if (task) { |
10901 | event->attach_state = PERF_ATTACH_TASK; | |
d580ff86 | 10902 | /* |
50f16a8b PZ |
10903 | * XXX pmu::event_init needs to know what task to account to |
10904 | * and we cannot use the ctx information because we need the | |
10905 | * pmu before we get a ctx. | |
d580ff86 | 10906 | */ |
7b3c92b8 | 10907 | event->hw.target = get_task_struct(task); |
d580ff86 PZ |
10908 | } |
10909 | ||
34f43927 PZ |
10910 | event->clock = &local_clock; |
10911 | if (parent_event) | |
10912 | event->clock = parent_event->clock; | |
10913 | ||
4dc0da86 | 10914 | if (!overflow_handler && parent_event) { |
b326e956 | 10915 | overflow_handler = parent_event->overflow_handler; |
4dc0da86 | 10916 | context = parent_event->overflow_handler_context; |
f1e4ba5b | 10917 | #if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_EVENT_TRACING) |
aa6a5f3c | 10918 | if (overflow_handler == bpf_overflow_handler) { |
85192dbf | 10919 | struct bpf_prog *prog = parent_event->prog; |
aa6a5f3c | 10920 | |
85192dbf | 10921 | bpf_prog_inc(prog); |
aa6a5f3c AS |
10922 | event->prog = prog; |
10923 | event->orig_overflow_handler = | |
10924 | parent_event->orig_overflow_handler; | |
10925 | } | |
10926 | #endif | |
4dc0da86 | 10927 | } |
66832eb4 | 10928 | |
1879445d WN |
10929 | if (overflow_handler) { |
10930 | event->overflow_handler = overflow_handler; | |
10931 | event->overflow_handler_context = context; | |
9ecda41a WN |
10932 | } else if (is_write_backward(event)){ |
10933 | event->overflow_handler = perf_event_output_backward; | |
10934 | event->overflow_handler_context = NULL; | |
1879445d | 10935 | } else { |
9ecda41a | 10936 | event->overflow_handler = perf_event_output_forward; |
1879445d WN |
10937 | event->overflow_handler_context = NULL; |
10938 | } | |
97eaf530 | 10939 | |
0231bb53 | 10940 | perf_event__state_init(event); |
a86ed508 | 10941 | |
4aeb0b42 | 10942 | pmu = NULL; |
b8e83514 | 10943 | |
cdd6c482 | 10944 | hwc = &event->hw; |
bd2b5b12 | 10945 | hwc->sample_period = attr->sample_period; |
0d48696f | 10946 | if (attr->freq && attr->sample_freq) |
bd2b5b12 | 10947 | hwc->sample_period = 1; |
eced1dfc | 10948 | hwc->last_period = hwc->sample_period; |
bd2b5b12 | 10949 | |
e7850595 | 10950 | local64_set(&hwc->period_left, hwc->sample_period); |
60db5e09 | 10951 | |
2023b359 | 10952 | /* |
ba5213ae PZ |
10953 | * We currently do not support PERF_SAMPLE_READ on inherited events. |
10954 | * See perf_output_read(). | |
2023b359 | 10955 | */ |
ba5213ae | 10956 | if (attr->inherit && (attr->sample_type & PERF_SAMPLE_READ)) |
90983b16 | 10957 | goto err_ns; |
a46a2300 YZ |
10958 | |
10959 | if (!has_branch_stack(event)) | |
10960 | event->attr.branch_sample_type = 0; | |
2023b359 | 10961 | |
b0a873eb | 10962 | pmu = perf_init_event(event); |
85c617ab | 10963 | if (IS_ERR(pmu)) { |
4aeb0b42 | 10964 | err = PTR_ERR(pmu); |
90983b16 | 10965 | goto err_ns; |
621a01ea | 10966 | } |
d5d2bc0d | 10967 | |
09f4e8f0 PZ |
10968 | /* |
10969 | * Disallow uncore-cgroup events, they don't make sense as the cgroup will | |
10970 | * be different on other CPUs in the uncore mask. | |
10971 | */ | |
10972 | if (pmu->task_ctx_nr == perf_invalid_context && cgroup_fd != -1) { | |
10973 | err = -EINVAL; | |
10974 | goto err_pmu; | |
10975 | } | |
10976 | ||
ab43762e AS |
10977 | if (event->attr.aux_output && |
10978 | !(pmu->capabilities & PERF_PMU_CAP_AUX_OUTPUT)) { | |
10979 | err = -EOPNOTSUPP; | |
10980 | goto err_pmu; | |
10981 | } | |
10982 | ||
98add2af PZ |
10983 | if (cgroup_fd != -1) { |
10984 | err = perf_cgroup_connect(cgroup_fd, event, attr, group_leader); | |
10985 | if (err) | |
10986 | goto err_pmu; | |
10987 | } | |
10988 | ||
bed5b25a AS |
10989 | err = exclusive_event_init(event); |
10990 | if (err) | |
10991 | goto err_pmu; | |
10992 | ||
375637bc | 10993 | if (has_addr_filter(event)) { |
c60f83b8 AS |
10994 | event->addr_filter_ranges = kcalloc(pmu->nr_addr_filters, |
10995 | sizeof(struct perf_addr_filter_range), | |
10996 | GFP_KERNEL); | |
10997 | if (!event->addr_filter_ranges) { | |
36cc2b92 | 10998 | err = -ENOMEM; |
375637bc | 10999 | goto err_per_task; |
36cc2b92 | 11000 | } |
375637bc | 11001 | |
18736eef AS |
11002 | /* |
11003 | * Clone the parent's vma offsets: they are valid until exec() | |
11004 | * even if the mm is not shared with the parent. | |
11005 | */ | |
11006 | if (event->parent) { | |
11007 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
11008 | ||
11009 | raw_spin_lock_irq(&ifh->lock); | |
c60f83b8 AS |
11010 | memcpy(event->addr_filter_ranges, |
11011 | event->parent->addr_filter_ranges, | |
11012 | pmu->nr_addr_filters * sizeof(struct perf_addr_filter_range)); | |
18736eef AS |
11013 | raw_spin_unlock_irq(&ifh->lock); |
11014 | } | |
11015 | ||
375637bc AS |
11016 | /* force hw sync on the address filters */ |
11017 | event->addr_filters_gen = 1; | |
11018 | } | |
11019 | ||
cdd6c482 | 11020 | if (!event->parent) { |
927c7a9e | 11021 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) { |
97c79a38 | 11022 | err = get_callchain_buffers(attr->sample_max_stack); |
90983b16 | 11023 | if (err) |
375637bc | 11024 | goto err_addr_filters; |
d010b332 | 11025 | } |
f344011c | 11026 | } |
9ee318a7 | 11027 | |
da97e184 JFG |
11028 | err = security_perf_event_alloc(event); |
11029 | if (err) | |
11030 | goto err_callchain_buffer; | |
11031 | ||
927a5570 AS |
11032 | /* symmetric to unaccount_event() in _free_event() */ |
11033 | account_event(event); | |
11034 | ||
cdd6c482 | 11035 | return event; |
90983b16 | 11036 | |
da97e184 JFG |
11037 | err_callchain_buffer: |
11038 | if (!event->parent) { | |
11039 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) | |
11040 | put_callchain_buffers(); | |
11041 | } | |
375637bc | 11042 | err_addr_filters: |
c60f83b8 | 11043 | kfree(event->addr_filter_ranges); |
375637bc | 11044 | |
bed5b25a AS |
11045 | err_per_task: |
11046 | exclusive_event_destroy(event); | |
11047 | ||
90983b16 | 11048 | err_pmu: |
98add2af PZ |
11049 | if (is_cgroup_event(event)) |
11050 | perf_detach_cgroup(event); | |
90983b16 FW |
11051 | if (event->destroy) |
11052 | event->destroy(event); | |
c464c76e | 11053 | module_put(pmu->module); |
90983b16 FW |
11054 | err_ns: |
11055 | if (event->ns) | |
11056 | put_pid_ns(event->ns); | |
621b6d2e PB |
11057 | if (event->hw.target) |
11058 | put_task_struct(event->hw.target); | |
90983b16 FW |
11059 | kfree(event); |
11060 | ||
11061 | return ERR_PTR(err); | |
0793a61d TG |
11062 | } |
11063 | ||
cdd6c482 IM |
11064 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
11065 | struct perf_event_attr *attr) | |
974802ea | 11066 | { |
974802ea | 11067 | u32 size; |
cdf8073d | 11068 | int ret; |
974802ea | 11069 | |
c2ba8f41 | 11070 | /* Zero the full structure, so that a short copy will be nice. */ |
974802ea PZ |
11071 | memset(attr, 0, sizeof(*attr)); |
11072 | ||
11073 | ret = get_user(size, &uattr->size); | |
11074 | if (ret) | |
11075 | return ret; | |
11076 | ||
c2ba8f41 AS |
11077 | /* ABI compatibility quirk: */ |
11078 | if (!size) | |
974802ea | 11079 | size = PERF_ATTR_SIZE_VER0; |
c2ba8f41 | 11080 | if (size < PERF_ATTR_SIZE_VER0 || size > PAGE_SIZE) |
974802ea PZ |
11081 | goto err_size; |
11082 | ||
c2ba8f41 AS |
11083 | ret = copy_struct_from_user(attr, sizeof(*attr), uattr, size); |
11084 | if (ret) { | |
11085 | if (ret == -E2BIG) | |
11086 | goto err_size; | |
11087 | return ret; | |
974802ea PZ |
11088 | } |
11089 | ||
f12f42ac MX |
11090 | attr->size = size; |
11091 | ||
a4faf00d | 11092 | if (attr->__reserved_1 || attr->__reserved_2 || attr->__reserved_3) |
974802ea PZ |
11093 | return -EINVAL; |
11094 | ||
11095 | if (attr->sample_type & ~(PERF_SAMPLE_MAX-1)) | |
11096 | return -EINVAL; | |
11097 | ||
11098 | if (attr->read_format & ~(PERF_FORMAT_MAX-1)) | |
11099 | return -EINVAL; | |
11100 | ||
bce38cd5 SE |
11101 | if (attr->sample_type & PERF_SAMPLE_BRANCH_STACK) { |
11102 | u64 mask = attr->branch_sample_type; | |
11103 | ||
11104 | /* only using defined bits */ | |
11105 | if (mask & ~(PERF_SAMPLE_BRANCH_MAX-1)) | |
11106 | return -EINVAL; | |
11107 | ||
11108 | /* at least one branch bit must be set */ | |
11109 | if (!(mask & ~PERF_SAMPLE_BRANCH_PLM_ALL)) | |
11110 | return -EINVAL; | |
11111 | ||
bce38cd5 SE |
11112 | /* propagate priv level, when not set for branch */ |
11113 | if (!(mask & PERF_SAMPLE_BRANCH_PLM_ALL)) { | |
11114 | ||
11115 | /* exclude_kernel checked on syscall entry */ | |
11116 | if (!attr->exclude_kernel) | |
11117 | mask |= PERF_SAMPLE_BRANCH_KERNEL; | |
11118 | ||
11119 | if (!attr->exclude_user) | |
11120 | mask |= PERF_SAMPLE_BRANCH_USER; | |
11121 | ||
11122 | if (!attr->exclude_hv) | |
11123 | mask |= PERF_SAMPLE_BRANCH_HV; | |
11124 | /* | |
11125 | * adjust user setting (for HW filter setup) | |
11126 | */ | |
11127 | attr->branch_sample_type = mask; | |
11128 | } | |
e712209a | 11129 | /* privileged levels capture (kernel, hv): check permissions */ |
da97e184 JFG |
11130 | if (mask & PERF_SAMPLE_BRANCH_PERM_PLM) { |
11131 | ret = perf_allow_kernel(attr); | |
11132 | if (ret) | |
11133 | return ret; | |
11134 | } | |
bce38cd5 | 11135 | } |
4018994f | 11136 | |
c5ebcedb | 11137 | if (attr->sample_type & PERF_SAMPLE_REGS_USER) { |
4018994f | 11138 | ret = perf_reg_validate(attr->sample_regs_user); |
c5ebcedb JO |
11139 | if (ret) |
11140 | return ret; | |
11141 | } | |
11142 | ||
11143 | if (attr->sample_type & PERF_SAMPLE_STACK_USER) { | |
11144 | if (!arch_perf_have_user_stack_dump()) | |
11145 | return -ENOSYS; | |
11146 | ||
11147 | /* | |
11148 | * We have __u32 type for the size, but so far | |
11149 | * we can only use __u16 as maximum due to the | |
11150 | * __u16 sample size limit. | |
11151 | */ | |
11152 | if (attr->sample_stack_user >= USHRT_MAX) | |
78b562fb | 11153 | return -EINVAL; |
c5ebcedb | 11154 | else if (!IS_ALIGNED(attr->sample_stack_user, sizeof(u64))) |
78b562fb | 11155 | return -EINVAL; |
c5ebcedb | 11156 | } |
4018994f | 11157 | |
5f970521 JO |
11158 | if (!attr->sample_max_stack) |
11159 | attr->sample_max_stack = sysctl_perf_event_max_stack; | |
11160 | ||
60e2364e SE |
11161 | if (attr->sample_type & PERF_SAMPLE_REGS_INTR) |
11162 | ret = perf_reg_validate(attr->sample_regs_intr); | |
974802ea PZ |
11163 | out: |
11164 | return ret; | |
11165 | ||
11166 | err_size: | |
11167 | put_user(sizeof(*attr), &uattr->size); | |
11168 | ret = -E2BIG; | |
11169 | goto out; | |
11170 | } | |
11171 | ||
ac9721f3 PZ |
11172 | static int |
11173 | perf_event_set_output(struct perf_event *event, struct perf_event *output_event) | |
a4be7c27 | 11174 | { |
56de4e8f | 11175 | struct perf_buffer *rb = NULL; |
a4be7c27 PZ |
11176 | int ret = -EINVAL; |
11177 | ||
ac9721f3 | 11178 | if (!output_event) |
a4be7c27 PZ |
11179 | goto set; |
11180 | ||
ac9721f3 PZ |
11181 | /* don't allow circular references */ |
11182 | if (event == output_event) | |
a4be7c27 PZ |
11183 | goto out; |
11184 | ||
0f139300 PZ |
11185 | /* |
11186 | * Don't allow cross-cpu buffers | |
11187 | */ | |
11188 | if (output_event->cpu != event->cpu) | |
11189 | goto out; | |
11190 | ||
11191 | /* | |
76369139 | 11192 | * If its not a per-cpu rb, it must be the same task. |
0f139300 PZ |
11193 | */ |
11194 | if (output_event->cpu == -1 && output_event->ctx != event->ctx) | |
11195 | goto out; | |
11196 | ||
34f43927 PZ |
11197 | /* |
11198 | * Mixing clocks in the same buffer is trouble you don't need. | |
11199 | */ | |
11200 | if (output_event->clock != event->clock) | |
11201 | goto out; | |
11202 | ||
9ecda41a WN |
11203 | /* |
11204 | * Either writing ring buffer from beginning or from end. | |
11205 | * Mixing is not allowed. | |
11206 | */ | |
11207 | if (is_write_backward(output_event) != is_write_backward(event)) | |
11208 | goto out; | |
11209 | ||
45bfb2e5 PZ |
11210 | /* |
11211 | * If both events generate aux data, they must be on the same PMU | |
11212 | */ | |
11213 | if (has_aux(event) && has_aux(output_event) && | |
11214 | event->pmu != output_event->pmu) | |
11215 | goto out; | |
11216 | ||
a4be7c27 | 11217 | set: |
cdd6c482 | 11218 | mutex_lock(&event->mmap_mutex); |
ac9721f3 PZ |
11219 | /* Can't redirect output if we've got an active mmap() */ |
11220 | if (atomic_read(&event->mmap_count)) | |
11221 | goto unlock; | |
a4be7c27 | 11222 | |
ac9721f3 | 11223 | if (output_event) { |
76369139 FW |
11224 | /* get the rb we want to redirect to */ |
11225 | rb = ring_buffer_get(output_event); | |
11226 | if (!rb) | |
ac9721f3 | 11227 | goto unlock; |
a4be7c27 PZ |
11228 | } |
11229 | ||
b69cf536 | 11230 | ring_buffer_attach(event, rb); |
9bb5d40c | 11231 | |
a4be7c27 | 11232 | ret = 0; |
ac9721f3 PZ |
11233 | unlock: |
11234 | mutex_unlock(&event->mmap_mutex); | |
11235 | ||
a4be7c27 | 11236 | out: |
a4be7c27 PZ |
11237 | return ret; |
11238 | } | |
11239 | ||
f63a8daa PZ |
11240 | static void mutex_lock_double(struct mutex *a, struct mutex *b) |
11241 | { | |
11242 | if (b < a) | |
11243 | swap(a, b); | |
11244 | ||
11245 | mutex_lock(a); | |
11246 | mutex_lock_nested(b, SINGLE_DEPTH_NESTING); | |
11247 | } | |
11248 | ||
34f43927 PZ |
11249 | static int perf_event_set_clock(struct perf_event *event, clockid_t clk_id) |
11250 | { | |
11251 | bool nmi_safe = false; | |
11252 | ||
11253 | switch (clk_id) { | |
11254 | case CLOCK_MONOTONIC: | |
11255 | event->clock = &ktime_get_mono_fast_ns; | |
11256 | nmi_safe = true; | |
11257 | break; | |
11258 | ||
11259 | case CLOCK_MONOTONIC_RAW: | |
11260 | event->clock = &ktime_get_raw_fast_ns; | |
11261 | nmi_safe = true; | |
11262 | break; | |
11263 | ||
11264 | case CLOCK_REALTIME: | |
11265 | event->clock = &ktime_get_real_ns; | |
11266 | break; | |
11267 | ||
11268 | case CLOCK_BOOTTIME: | |
9285ec4c | 11269 | event->clock = &ktime_get_boottime_ns; |
34f43927 PZ |
11270 | break; |
11271 | ||
11272 | case CLOCK_TAI: | |
9285ec4c | 11273 | event->clock = &ktime_get_clocktai_ns; |
34f43927 PZ |
11274 | break; |
11275 | ||
11276 | default: | |
11277 | return -EINVAL; | |
11278 | } | |
11279 | ||
11280 | if (!nmi_safe && !(event->pmu->capabilities & PERF_PMU_CAP_NO_NMI)) | |
11281 | return -EINVAL; | |
11282 | ||
11283 | return 0; | |
11284 | } | |
11285 | ||
321027c1 PZ |
11286 | /* |
11287 | * Variation on perf_event_ctx_lock_nested(), except we take two context | |
11288 | * mutexes. | |
11289 | */ | |
11290 | static struct perf_event_context * | |
11291 | __perf_event_ctx_lock_double(struct perf_event *group_leader, | |
11292 | struct perf_event_context *ctx) | |
11293 | { | |
11294 | struct perf_event_context *gctx; | |
11295 | ||
11296 | again: | |
11297 | rcu_read_lock(); | |
11298 | gctx = READ_ONCE(group_leader->ctx); | |
8c94abbb | 11299 | if (!refcount_inc_not_zero(&gctx->refcount)) { |
321027c1 PZ |
11300 | rcu_read_unlock(); |
11301 | goto again; | |
11302 | } | |
11303 | rcu_read_unlock(); | |
11304 | ||
11305 | mutex_lock_double(&gctx->mutex, &ctx->mutex); | |
11306 | ||
11307 | if (group_leader->ctx != gctx) { | |
11308 | mutex_unlock(&ctx->mutex); | |
11309 | mutex_unlock(&gctx->mutex); | |
11310 | put_ctx(gctx); | |
11311 | goto again; | |
11312 | } | |
11313 | ||
11314 | return gctx; | |
11315 | } | |
11316 | ||
0793a61d | 11317 | /** |
cdd6c482 | 11318 | * sys_perf_event_open - open a performance event, associate it to a task/cpu |
9f66a381 | 11319 | * |
cdd6c482 | 11320 | * @attr_uptr: event_id type attributes for monitoring/sampling |
0793a61d | 11321 | * @pid: target pid |
9f66a381 | 11322 | * @cpu: target cpu |
cdd6c482 | 11323 | * @group_fd: group leader event fd |
0793a61d | 11324 | */ |
cdd6c482 IM |
11325 | SYSCALL_DEFINE5(perf_event_open, |
11326 | struct perf_event_attr __user *, attr_uptr, | |
2743a5b0 | 11327 | pid_t, pid, int, cpu, int, group_fd, unsigned long, flags) |
0793a61d | 11328 | { |
b04243ef PZ |
11329 | struct perf_event *group_leader = NULL, *output_event = NULL; |
11330 | struct perf_event *event, *sibling; | |
cdd6c482 | 11331 | struct perf_event_attr attr; |
f63a8daa | 11332 | struct perf_event_context *ctx, *uninitialized_var(gctx); |
cdd6c482 | 11333 | struct file *event_file = NULL; |
2903ff01 | 11334 | struct fd group = {NULL, 0}; |
38a81da2 | 11335 | struct task_struct *task = NULL; |
89a1e187 | 11336 | struct pmu *pmu; |
ea635c64 | 11337 | int event_fd; |
b04243ef | 11338 | int move_group = 0; |
dc86cabe | 11339 | int err; |
a21b0b35 | 11340 | int f_flags = O_RDWR; |
79dff51e | 11341 | int cgroup_fd = -1; |
0793a61d | 11342 | |
2743a5b0 | 11343 | /* for future expandability... */ |
e5d1367f | 11344 | if (flags & ~PERF_FLAG_ALL) |
2743a5b0 PM |
11345 | return -EINVAL; |
11346 | ||
da97e184 JFG |
11347 | /* Do we allow access to perf_event_open(2) ? */ |
11348 | err = security_perf_event_open(&attr, PERF_SECURITY_OPEN); | |
11349 | if (err) | |
11350 | return err; | |
11351 | ||
dc86cabe IM |
11352 | err = perf_copy_attr(attr_uptr, &attr); |
11353 | if (err) | |
11354 | return err; | |
eab656ae | 11355 | |
0764771d | 11356 | if (!attr.exclude_kernel) { |
da97e184 JFG |
11357 | err = perf_allow_kernel(&attr); |
11358 | if (err) | |
11359 | return err; | |
0764771d PZ |
11360 | } |
11361 | ||
e4222673 HB |
11362 | if (attr.namespaces) { |
11363 | if (!capable(CAP_SYS_ADMIN)) | |
11364 | return -EACCES; | |
11365 | } | |
11366 | ||
df58ab24 | 11367 | if (attr.freq) { |
cdd6c482 | 11368 | if (attr.sample_freq > sysctl_perf_event_sample_rate) |
df58ab24 | 11369 | return -EINVAL; |
0819b2e3 PZ |
11370 | } else { |
11371 | if (attr.sample_period & (1ULL << 63)) | |
11372 | return -EINVAL; | |
df58ab24 PZ |
11373 | } |
11374 | ||
fc7ce9c7 | 11375 | /* Only privileged users can get physical addresses */ |
da97e184 JFG |
11376 | if ((attr.sample_type & PERF_SAMPLE_PHYS_ADDR)) { |
11377 | err = perf_allow_kernel(&attr); | |
11378 | if (err) | |
11379 | return err; | |
11380 | } | |
fc7ce9c7 | 11381 | |
b0c8fdc7 DH |
11382 | err = security_locked_down(LOCKDOWN_PERF); |
11383 | if (err && (attr.sample_type & PERF_SAMPLE_REGS_INTR)) | |
11384 | /* REGS_INTR can leak data, lockdown must prevent this */ | |
11385 | return err; | |
11386 | ||
11387 | err = 0; | |
11388 | ||
e5d1367f SE |
11389 | /* |
11390 | * In cgroup mode, the pid argument is used to pass the fd | |
11391 | * opened to the cgroup directory in cgroupfs. The cpu argument | |
11392 | * designates the cpu on which to monitor threads from that | |
11393 | * cgroup. | |
11394 | */ | |
11395 | if ((flags & PERF_FLAG_PID_CGROUP) && (pid == -1 || cpu == -1)) | |
11396 | return -EINVAL; | |
11397 | ||
a21b0b35 YD |
11398 | if (flags & PERF_FLAG_FD_CLOEXEC) |
11399 | f_flags |= O_CLOEXEC; | |
11400 | ||
11401 | event_fd = get_unused_fd_flags(f_flags); | |
ea635c64 AV |
11402 | if (event_fd < 0) |
11403 | return event_fd; | |
11404 | ||
ac9721f3 | 11405 | if (group_fd != -1) { |
2903ff01 AV |
11406 | err = perf_fget_light(group_fd, &group); |
11407 | if (err) | |
d14b12d7 | 11408 | goto err_fd; |
2903ff01 | 11409 | group_leader = group.file->private_data; |
ac9721f3 PZ |
11410 | if (flags & PERF_FLAG_FD_OUTPUT) |
11411 | output_event = group_leader; | |
11412 | if (flags & PERF_FLAG_FD_NO_GROUP) | |
11413 | group_leader = NULL; | |
11414 | } | |
11415 | ||
e5d1367f | 11416 | if (pid != -1 && !(flags & PERF_FLAG_PID_CGROUP)) { |
c6be5a5c PZ |
11417 | task = find_lively_task_by_vpid(pid); |
11418 | if (IS_ERR(task)) { | |
11419 | err = PTR_ERR(task); | |
11420 | goto err_group_fd; | |
11421 | } | |
11422 | } | |
11423 | ||
1f4ee503 PZ |
11424 | if (task && group_leader && |
11425 | group_leader->attr.inherit != attr.inherit) { | |
11426 | err = -EINVAL; | |
11427 | goto err_task; | |
11428 | } | |
11429 | ||
79c9ce57 PZ |
11430 | if (task) { |
11431 | err = mutex_lock_interruptible(&task->signal->cred_guard_mutex); | |
11432 | if (err) | |
e5aeee51 | 11433 | goto err_task; |
79c9ce57 PZ |
11434 | |
11435 | /* | |
11436 | * Reuse ptrace permission checks for now. | |
11437 | * | |
11438 | * We must hold cred_guard_mutex across this and any potential | |
11439 | * perf_install_in_context() call for this new event to | |
11440 | * serialize against exec() altering our credentials (and the | |
11441 | * perf_event_exit_task() that could imply). | |
11442 | */ | |
11443 | err = -EACCES; | |
11444 | if (!ptrace_may_access(task, PTRACE_MODE_READ_REALCREDS)) | |
11445 | goto err_cred; | |
11446 | } | |
11447 | ||
79dff51e MF |
11448 | if (flags & PERF_FLAG_PID_CGROUP) |
11449 | cgroup_fd = pid; | |
11450 | ||
4dc0da86 | 11451 | event = perf_event_alloc(&attr, cpu, task, group_leader, NULL, |
79dff51e | 11452 | NULL, NULL, cgroup_fd); |
d14b12d7 SE |
11453 | if (IS_ERR(event)) { |
11454 | err = PTR_ERR(event); | |
79c9ce57 | 11455 | goto err_cred; |
d14b12d7 SE |
11456 | } |
11457 | ||
53b25335 VW |
11458 | if (is_sampling_event(event)) { |
11459 | if (event->pmu->capabilities & PERF_PMU_CAP_NO_INTERRUPT) { | |
a1396555 | 11460 | err = -EOPNOTSUPP; |
53b25335 VW |
11461 | goto err_alloc; |
11462 | } | |
11463 | } | |
11464 | ||
89a1e187 PZ |
11465 | /* |
11466 | * Special case software events and allow them to be part of | |
11467 | * any hardware group. | |
11468 | */ | |
11469 | pmu = event->pmu; | |
b04243ef | 11470 | |
34f43927 PZ |
11471 | if (attr.use_clockid) { |
11472 | err = perf_event_set_clock(event, attr.clockid); | |
11473 | if (err) | |
11474 | goto err_alloc; | |
11475 | } | |
11476 | ||
4ff6a8de DCC |
11477 | if (pmu->task_ctx_nr == perf_sw_context) |
11478 | event->event_caps |= PERF_EV_CAP_SOFTWARE; | |
11479 | ||
a1150c20 SL |
11480 | if (group_leader) { |
11481 | if (is_software_event(event) && | |
11482 | !in_software_context(group_leader)) { | |
b04243ef | 11483 | /* |
a1150c20 SL |
11484 | * If the event is a sw event, but the group_leader |
11485 | * is on hw context. | |
b04243ef | 11486 | * |
a1150c20 SL |
11487 | * Allow the addition of software events to hw |
11488 | * groups, this is safe because software events | |
11489 | * never fail to schedule. | |
b04243ef | 11490 | */ |
a1150c20 SL |
11491 | pmu = group_leader->ctx->pmu; |
11492 | } else if (!is_software_event(event) && | |
11493 | is_software_event(group_leader) && | |
4ff6a8de | 11494 | (group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { |
b04243ef PZ |
11495 | /* |
11496 | * In case the group is a pure software group, and we | |
11497 | * try to add a hardware event, move the whole group to | |
11498 | * the hardware context. | |
11499 | */ | |
11500 | move_group = 1; | |
11501 | } | |
11502 | } | |
89a1e187 PZ |
11503 | |
11504 | /* | |
11505 | * Get the target context (task or percpu): | |
11506 | */ | |
4af57ef2 | 11507 | ctx = find_get_context(pmu, task, event); |
89a1e187 PZ |
11508 | if (IS_ERR(ctx)) { |
11509 | err = PTR_ERR(ctx); | |
c6be5a5c | 11510 | goto err_alloc; |
89a1e187 PZ |
11511 | } |
11512 | ||
ccff286d | 11513 | /* |
cdd6c482 | 11514 | * Look up the group leader (we will attach this event to it): |
04289bb9 | 11515 | */ |
ac9721f3 | 11516 | if (group_leader) { |
dc86cabe | 11517 | err = -EINVAL; |
04289bb9 | 11518 | |
04289bb9 | 11519 | /* |
ccff286d IM |
11520 | * Do not allow a recursive hierarchy (this new sibling |
11521 | * becoming part of another group-sibling): | |
11522 | */ | |
11523 | if (group_leader->group_leader != group_leader) | |
c3f00c70 | 11524 | goto err_context; |
34f43927 PZ |
11525 | |
11526 | /* All events in a group should have the same clock */ | |
11527 | if (group_leader->clock != event->clock) | |
11528 | goto err_context; | |
11529 | ||
ccff286d | 11530 | /* |
64aee2a9 MR |
11531 | * Make sure we're both events for the same CPU; |
11532 | * grouping events for different CPUs is broken; since | |
11533 | * you can never concurrently schedule them anyhow. | |
04289bb9 | 11534 | */ |
64aee2a9 MR |
11535 | if (group_leader->cpu != event->cpu) |
11536 | goto err_context; | |
c3c87e77 | 11537 | |
64aee2a9 MR |
11538 | /* |
11539 | * Make sure we're both on the same task, or both | |
11540 | * per-CPU events. | |
11541 | */ | |
11542 | if (group_leader->ctx->task != ctx->task) | |
11543 | goto err_context; | |
11544 | ||
11545 | /* | |
11546 | * Do not allow to attach to a group in a different task | |
11547 | * or CPU context. If we're moving SW events, we'll fix | |
11548 | * this up later, so allow that. | |
11549 | */ | |
11550 | if (!move_group && group_leader->ctx != ctx) | |
11551 | goto err_context; | |
b04243ef | 11552 | |
3b6f9e5c PM |
11553 | /* |
11554 | * Only a group leader can be exclusive or pinned | |
11555 | */ | |
0d48696f | 11556 | if (attr.exclusive || attr.pinned) |
c3f00c70 | 11557 | goto err_context; |
ac9721f3 PZ |
11558 | } |
11559 | ||
11560 | if (output_event) { | |
11561 | err = perf_event_set_output(event, output_event); | |
11562 | if (err) | |
c3f00c70 | 11563 | goto err_context; |
ac9721f3 | 11564 | } |
0793a61d | 11565 | |
a21b0b35 YD |
11566 | event_file = anon_inode_getfile("[perf_event]", &perf_fops, event, |
11567 | f_flags); | |
ea635c64 AV |
11568 | if (IS_ERR(event_file)) { |
11569 | err = PTR_ERR(event_file); | |
201c2f85 | 11570 | event_file = NULL; |
c3f00c70 | 11571 | goto err_context; |
ea635c64 | 11572 | } |
9b51f66d | 11573 | |
b04243ef | 11574 | if (move_group) { |
321027c1 PZ |
11575 | gctx = __perf_event_ctx_lock_double(group_leader, ctx); |
11576 | ||
84c4e620 PZ |
11577 | if (gctx->task == TASK_TOMBSTONE) { |
11578 | err = -ESRCH; | |
11579 | goto err_locked; | |
11580 | } | |
321027c1 PZ |
11581 | |
11582 | /* | |
11583 | * Check if we raced against another sys_perf_event_open() call | |
11584 | * moving the software group underneath us. | |
11585 | */ | |
11586 | if (!(group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { | |
11587 | /* | |
11588 | * If someone moved the group out from under us, check | |
11589 | * if this new event wound up on the same ctx, if so | |
11590 | * its the regular !move_group case, otherwise fail. | |
11591 | */ | |
11592 | if (gctx != ctx) { | |
11593 | err = -EINVAL; | |
11594 | goto err_locked; | |
11595 | } else { | |
11596 | perf_event_ctx_unlock(group_leader, gctx); | |
11597 | move_group = 0; | |
11598 | } | |
11599 | } | |
8a58ddae AS |
11600 | |
11601 | /* | |
11602 | * Failure to create exclusive events returns -EBUSY. | |
11603 | */ | |
11604 | err = -EBUSY; | |
11605 | if (!exclusive_event_installable(group_leader, ctx)) | |
11606 | goto err_locked; | |
11607 | ||
11608 | for_each_sibling_event(sibling, group_leader) { | |
11609 | if (!exclusive_event_installable(sibling, ctx)) | |
11610 | goto err_locked; | |
11611 | } | |
f55fc2a5 PZ |
11612 | } else { |
11613 | mutex_lock(&ctx->mutex); | |
11614 | } | |
11615 | ||
84c4e620 PZ |
11616 | if (ctx->task == TASK_TOMBSTONE) { |
11617 | err = -ESRCH; | |
11618 | goto err_locked; | |
11619 | } | |
11620 | ||
a723968c PZ |
11621 | if (!perf_event_validate_size(event)) { |
11622 | err = -E2BIG; | |
11623 | goto err_locked; | |
11624 | } | |
11625 | ||
a63fbed7 TG |
11626 | if (!task) { |
11627 | /* | |
11628 | * Check if the @cpu we're creating an event for is online. | |
11629 | * | |
11630 | * We use the perf_cpu_context::ctx::mutex to serialize against | |
11631 | * the hotplug notifiers. See perf_event_{init,exit}_cpu(). | |
11632 | */ | |
11633 | struct perf_cpu_context *cpuctx = | |
11634 | container_of(ctx, struct perf_cpu_context, ctx); | |
11635 | ||
11636 | if (!cpuctx->online) { | |
11637 | err = -ENODEV; | |
11638 | goto err_locked; | |
11639 | } | |
11640 | } | |
11641 | ||
da9ec3d3 MR |
11642 | if (perf_need_aux_event(event) && !perf_get_aux_event(event, group_leader)) { |
11643 | err = -EINVAL; | |
ab43762e | 11644 | goto err_locked; |
da9ec3d3 | 11645 | } |
a63fbed7 | 11646 | |
f55fc2a5 PZ |
11647 | /* |
11648 | * Must be under the same ctx::mutex as perf_install_in_context(), | |
11649 | * because we need to serialize with concurrent event creation. | |
11650 | */ | |
11651 | if (!exclusive_event_installable(event, ctx)) { | |
f55fc2a5 PZ |
11652 | err = -EBUSY; |
11653 | goto err_locked; | |
11654 | } | |
f63a8daa | 11655 | |
f55fc2a5 PZ |
11656 | WARN_ON_ONCE(ctx->parent_ctx); |
11657 | ||
79c9ce57 PZ |
11658 | /* |
11659 | * This is the point on no return; we cannot fail hereafter. This is | |
11660 | * where we start modifying current state. | |
11661 | */ | |
11662 | ||
f55fc2a5 | 11663 | if (move_group) { |
f63a8daa PZ |
11664 | /* |
11665 | * See perf_event_ctx_lock() for comments on the details | |
11666 | * of swizzling perf_event::ctx. | |
11667 | */ | |
45a0e07a | 11668 | perf_remove_from_context(group_leader, 0); |
279b5165 | 11669 | put_ctx(gctx); |
0231bb53 | 11670 | |
edb39592 | 11671 | for_each_sibling_event(sibling, group_leader) { |
45a0e07a | 11672 | perf_remove_from_context(sibling, 0); |
b04243ef PZ |
11673 | put_ctx(gctx); |
11674 | } | |
b04243ef | 11675 | |
f63a8daa PZ |
11676 | /* |
11677 | * Wait for everybody to stop referencing the events through | |
11678 | * the old lists, before installing it on new lists. | |
11679 | */ | |
0cda4c02 | 11680 | synchronize_rcu(); |
f63a8daa | 11681 | |
8f95b435 PZI |
11682 | /* |
11683 | * Install the group siblings before the group leader. | |
11684 | * | |
11685 | * Because a group leader will try and install the entire group | |
11686 | * (through the sibling list, which is still in-tact), we can | |
11687 | * end up with siblings installed in the wrong context. | |
11688 | * | |
11689 | * By installing siblings first we NO-OP because they're not | |
11690 | * reachable through the group lists. | |
11691 | */ | |
edb39592 | 11692 | for_each_sibling_event(sibling, group_leader) { |
8f95b435 | 11693 | perf_event__state_init(sibling); |
9fc81d87 | 11694 | perf_install_in_context(ctx, sibling, sibling->cpu); |
b04243ef PZ |
11695 | get_ctx(ctx); |
11696 | } | |
8f95b435 PZI |
11697 | |
11698 | /* | |
11699 | * Removing from the context ends up with disabled | |
11700 | * event. What we want here is event in the initial | |
11701 | * startup state, ready to be add into new context. | |
11702 | */ | |
11703 | perf_event__state_init(group_leader); | |
11704 | perf_install_in_context(ctx, group_leader, group_leader->cpu); | |
11705 | get_ctx(ctx); | |
bed5b25a AS |
11706 | } |
11707 | ||
f73e22ab PZ |
11708 | /* |
11709 | * Precalculate sample_data sizes; do while holding ctx::mutex such | |
11710 | * that we're serialized against further additions and before | |
11711 | * perf_install_in_context() which is the point the event is active and | |
11712 | * can use these values. | |
11713 | */ | |
11714 | perf_event__header_size(event); | |
11715 | perf_event__id_header_size(event); | |
11716 | ||
78cd2c74 PZ |
11717 | event->owner = current; |
11718 | ||
e2d37cd2 | 11719 | perf_install_in_context(ctx, event, event->cpu); |
fe4b04fa | 11720 | perf_unpin_context(ctx); |
f63a8daa | 11721 | |
f55fc2a5 | 11722 | if (move_group) |
321027c1 | 11723 | perf_event_ctx_unlock(group_leader, gctx); |
d859e29f | 11724 | mutex_unlock(&ctx->mutex); |
9b51f66d | 11725 | |
79c9ce57 PZ |
11726 | if (task) { |
11727 | mutex_unlock(&task->signal->cred_guard_mutex); | |
11728 | put_task_struct(task); | |
11729 | } | |
11730 | ||
cdd6c482 IM |
11731 | mutex_lock(¤t->perf_event_mutex); |
11732 | list_add_tail(&event->owner_entry, ¤t->perf_event_list); | |
11733 | mutex_unlock(¤t->perf_event_mutex); | |
082ff5a2 | 11734 | |
8a49542c PZ |
11735 | /* |
11736 | * Drop the reference on the group_event after placing the | |
11737 | * new event on the sibling_list. This ensures destruction | |
11738 | * of the group leader will find the pointer to itself in | |
11739 | * perf_group_detach(). | |
11740 | */ | |
2903ff01 | 11741 | fdput(group); |
ea635c64 AV |
11742 | fd_install(event_fd, event_file); |
11743 | return event_fd; | |
0793a61d | 11744 | |
f55fc2a5 PZ |
11745 | err_locked: |
11746 | if (move_group) | |
321027c1 | 11747 | perf_event_ctx_unlock(group_leader, gctx); |
f55fc2a5 PZ |
11748 | mutex_unlock(&ctx->mutex); |
11749 | /* err_file: */ | |
11750 | fput(event_file); | |
c3f00c70 | 11751 | err_context: |
fe4b04fa | 11752 | perf_unpin_context(ctx); |
ea635c64 | 11753 | put_ctx(ctx); |
c6be5a5c | 11754 | err_alloc: |
13005627 PZ |
11755 | /* |
11756 | * If event_file is set, the fput() above will have called ->release() | |
11757 | * and that will take care of freeing the event. | |
11758 | */ | |
11759 | if (!event_file) | |
11760 | free_event(event); | |
79c9ce57 PZ |
11761 | err_cred: |
11762 | if (task) | |
11763 | mutex_unlock(&task->signal->cred_guard_mutex); | |
1f4ee503 | 11764 | err_task: |
e7d0bc04 PZ |
11765 | if (task) |
11766 | put_task_struct(task); | |
89a1e187 | 11767 | err_group_fd: |
2903ff01 | 11768 | fdput(group); |
ea635c64 AV |
11769 | err_fd: |
11770 | put_unused_fd(event_fd); | |
dc86cabe | 11771 | return err; |
0793a61d TG |
11772 | } |
11773 | ||
fb0459d7 AV |
11774 | /** |
11775 | * perf_event_create_kernel_counter | |
11776 | * | |
11777 | * @attr: attributes of the counter to create | |
11778 | * @cpu: cpu in which the counter is bound | |
38a81da2 | 11779 | * @task: task to profile (NULL for percpu) |
fb0459d7 AV |
11780 | */ |
11781 | struct perf_event * | |
11782 | perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, | |
38a81da2 | 11783 | struct task_struct *task, |
4dc0da86 AK |
11784 | perf_overflow_handler_t overflow_handler, |
11785 | void *context) | |
fb0459d7 | 11786 | { |
fb0459d7 | 11787 | struct perf_event_context *ctx; |
c3f00c70 | 11788 | struct perf_event *event; |
fb0459d7 | 11789 | int err; |
d859e29f | 11790 | |
dce5affb AS |
11791 | /* |
11792 | * Grouping is not supported for kernel events, neither is 'AUX', | |
11793 | * make sure the caller's intentions are adjusted. | |
11794 | */ | |
11795 | if (attr->aux_output) | |
11796 | return ERR_PTR(-EINVAL); | |
11797 | ||
4dc0da86 | 11798 | event = perf_event_alloc(attr, cpu, task, NULL, NULL, |
79dff51e | 11799 | overflow_handler, context, -1); |
c3f00c70 PZ |
11800 | if (IS_ERR(event)) { |
11801 | err = PTR_ERR(event); | |
11802 | goto err; | |
11803 | } | |
d859e29f | 11804 | |
f8697762 | 11805 | /* Mark owner so we could distinguish it from user events. */ |
63b6da39 | 11806 | event->owner = TASK_TOMBSTONE; |
f8697762 | 11807 | |
f25d8ba9 AS |
11808 | /* |
11809 | * Get the target context (task or percpu): | |
11810 | */ | |
4af57ef2 | 11811 | ctx = find_get_context(event->pmu, task, event); |
c6567f64 FW |
11812 | if (IS_ERR(ctx)) { |
11813 | err = PTR_ERR(ctx); | |
c3f00c70 | 11814 | goto err_free; |
d859e29f | 11815 | } |
fb0459d7 | 11816 | |
fb0459d7 AV |
11817 | WARN_ON_ONCE(ctx->parent_ctx); |
11818 | mutex_lock(&ctx->mutex); | |
84c4e620 PZ |
11819 | if (ctx->task == TASK_TOMBSTONE) { |
11820 | err = -ESRCH; | |
11821 | goto err_unlock; | |
11822 | } | |
11823 | ||
a63fbed7 TG |
11824 | if (!task) { |
11825 | /* | |
11826 | * Check if the @cpu we're creating an event for is online. | |
11827 | * | |
11828 | * We use the perf_cpu_context::ctx::mutex to serialize against | |
11829 | * the hotplug notifiers. See perf_event_{init,exit}_cpu(). | |
11830 | */ | |
11831 | struct perf_cpu_context *cpuctx = | |
11832 | container_of(ctx, struct perf_cpu_context, ctx); | |
11833 | if (!cpuctx->online) { | |
11834 | err = -ENODEV; | |
11835 | goto err_unlock; | |
11836 | } | |
11837 | } | |
11838 | ||
bed5b25a | 11839 | if (!exclusive_event_installable(event, ctx)) { |
bed5b25a | 11840 | err = -EBUSY; |
84c4e620 | 11841 | goto err_unlock; |
bed5b25a AS |
11842 | } |
11843 | ||
4ce54af8 | 11844 | perf_install_in_context(ctx, event, event->cpu); |
fe4b04fa | 11845 | perf_unpin_context(ctx); |
fb0459d7 AV |
11846 | mutex_unlock(&ctx->mutex); |
11847 | ||
fb0459d7 AV |
11848 | return event; |
11849 | ||
84c4e620 PZ |
11850 | err_unlock: |
11851 | mutex_unlock(&ctx->mutex); | |
11852 | perf_unpin_context(ctx); | |
11853 | put_ctx(ctx); | |
c3f00c70 PZ |
11854 | err_free: |
11855 | free_event(event); | |
11856 | err: | |
c6567f64 | 11857 | return ERR_PTR(err); |
9b51f66d | 11858 | } |
fb0459d7 | 11859 | EXPORT_SYMBOL_GPL(perf_event_create_kernel_counter); |
9b51f66d | 11860 | |
0cda4c02 YZ |
11861 | void perf_pmu_migrate_context(struct pmu *pmu, int src_cpu, int dst_cpu) |
11862 | { | |
11863 | struct perf_event_context *src_ctx; | |
11864 | struct perf_event_context *dst_ctx; | |
11865 | struct perf_event *event, *tmp; | |
11866 | LIST_HEAD(events); | |
11867 | ||
11868 | src_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, src_cpu)->ctx; | |
11869 | dst_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, dst_cpu)->ctx; | |
11870 | ||
f63a8daa PZ |
11871 | /* |
11872 | * See perf_event_ctx_lock() for comments on the details | |
11873 | * of swizzling perf_event::ctx. | |
11874 | */ | |
11875 | mutex_lock_double(&src_ctx->mutex, &dst_ctx->mutex); | |
0cda4c02 YZ |
11876 | list_for_each_entry_safe(event, tmp, &src_ctx->event_list, |
11877 | event_entry) { | |
45a0e07a | 11878 | perf_remove_from_context(event, 0); |
9a545de0 | 11879 | unaccount_event_cpu(event, src_cpu); |
0cda4c02 | 11880 | put_ctx(src_ctx); |
9886167d | 11881 | list_add(&event->migrate_entry, &events); |
0cda4c02 | 11882 | } |
0cda4c02 | 11883 | |
8f95b435 PZI |
11884 | /* |
11885 | * Wait for the events to quiesce before re-instating them. | |
11886 | */ | |
0cda4c02 YZ |
11887 | synchronize_rcu(); |
11888 | ||
8f95b435 PZI |
11889 | /* |
11890 | * Re-instate events in 2 passes. | |
11891 | * | |
11892 | * Skip over group leaders and only install siblings on this first | |
11893 | * pass, siblings will not get enabled without a leader, however a | |
11894 | * leader will enable its siblings, even if those are still on the old | |
11895 | * context. | |
11896 | */ | |
11897 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { | |
11898 | if (event->group_leader == event) | |
11899 | continue; | |
11900 | ||
11901 | list_del(&event->migrate_entry); | |
11902 | if (event->state >= PERF_EVENT_STATE_OFF) | |
11903 | event->state = PERF_EVENT_STATE_INACTIVE; | |
11904 | account_event_cpu(event, dst_cpu); | |
11905 | perf_install_in_context(dst_ctx, event, dst_cpu); | |
11906 | get_ctx(dst_ctx); | |
11907 | } | |
11908 | ||
11909 | /* | |
11910 | * Once all the siblings are setup properly, install the group leaders | |
11911 | * to make it go. | |
11912 | */ | |
9886167d PZ |
11913 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { |
11914 | list_del(&event->migrate_entry); | |
0cda4c02 YZ |
11915 | if (event->state >= PERF_EVENT_STATE_OFF) |
11916 | event->state = PERF_EVENT_STATE_INACTIVE; | |
9a545de0 | 11917 | account_event_cpu(event, dst_cpu); |
0cda4c02 YZ |
11918 | perf_install_in_context(dst_ctx, event, dst_cpu); |
11919 | get_ctx(dst_ctx); | |
11920 | } | |
11921 | mutex_unlock(&dst_ctx->mutex); | |
f63a8daa | 11922 | mutex_unlock(&src_ctx->mutex); |
0cda4c02 YZ |
11923 | } |
11924 | EXPORT_SYMBOL_GPL(perf_pmu_migrate_context); | |
11925 | ||
cdd6c482 | 11926 | static void sync_child_event(struct perf_event *child_event, |
38b200d6 | 11927 | struct task_struct *child) |
d859e29f | 11928 | { |
cdd6c482 | 11929 | struct perf_event *parent_event = child_event->parent; |
8bc20959 | 11930 | u64 child_val; |
d859e29f | 11931 | |
cdd6c482 IM |
11932 | if (child_event->attr.inherit_stat) |
11933 | perf_event_read_event(child_event, child); | |
38b200d6 | 11934 | |
b5e58793 | 11935 | child_val = perf_event_count(child_event); |
d859e29f PM |
11936 | |
11937 | /* | |
11938 | * Add back the child's count to the parent's count: | |
11939 | */ | |
a6e6dea6 | 11940 | atomic64_add(child_val, &parent_event->child_count); |
cdd6c482 IM |
11941 | atomic64_add(child_event->total_time_enabled, |
11942 | &parent_event->child_total_time_enabled); | |
11943 | atomic64_add(child_event->total_time_running, | |
11944 | &parent_event->child_total_time_running); | |
d859e29f PM |
11945 | } |
11946 | ||
9b51f66d | 11947 | static void |
8ba289b8 PZ |
11948 | perf_event_exit_event(struct perf_event *child_event, |
11949 | struct perf_event_context *child_ctx, | |
11950 | struct task_struct *child) | |
9b51f66d | 11951 | { |
8ba289b8 PZ |
11952 | struct perf_event *parent_event = child_event->parent; |
11953 | ||
1903d50c PZ |
11954 | /* |
11955 | * Do not destroy the 'original' grouping; because of the context | |
11956 | * switch optimization the original events could've ended up in a | |
11957 | * random child task. | |
11958 | * | |
11959 | * If we were to destroy the original group, all group related | |
11960 | * operations would cease to function properly after this random | |
11961 | * child dies. | |
11962 | * | |
11963 | * Do destroy all inherited groups, we don't care about those | |
11964 | * and being thorough is better. | |
11965 | */ | |
32132a3d PZ |
11966 | raw_spin_lock_irq(&child_ctx->lock); |
11967 | WARN_ON_ONCE(child_ctx->is_active); | |
11968 | ||
8ba289b8 | 11969 | if (parent_event) |
32132a3d PZ |
11970 | perf_group_detach(child_event); |
11971 | list_del_event(child_event, child_ctx); | |
0d3d73aa | 11972 | perf_event_set_state(child_event, PERF_EVENT_STATE_EXIT); /* is_event_hup() */ |
32132a3d | 11973 | raw_spin_unlock_irq(&child_ctx->lock); |
0cc0c027 | 11974 | |
9b51f66d | 11975 | /* |
8ba289b8 | 11976 | * Parent events are governed by their filedesc, retain them. |
9b51f66d | 11977 | */ |
8ba289b8 | 11978 | if (!parent_event) { |
179033b3 | 11979 | perf_event_wakeup(child_event); |
8ba289b8 | 11980 | return; |
4bcf349a | 11981 | } |
8ba289b8 PZ |
11982 | /* |
11983 | * Child events can be cleaned up. | |
11984 | */ | |
11985 | ||
11986 | sync_child_event(child_event, child); | |
11987 | ||
11988 | /* | |
11989 | * Remove this event from the parent's list | |
11990 | */ | |
11991 | WARN_ON_ONCE(parent_event->ctx->parent_ctx); | |
11992 | mutex_lock(&parent_event->child_mutex); | |
11993 | list_del_init(&child_event->child_list); | |
11994 | mutex_unlock(&parent_event->child_mutex); | |
11995 | ||
11996 | /* | |
11997 | * Kick perf_poll() for is_event_hup(). | |
11998 | */ | |
11999 | perf_event_wakeup(parent_event); | |
12000 | free_event(child_event); | |
12001 | put_event(parent_event); | |
9b51f66d IM |
12002 | } |
12003 | ||
8dc85d54 | 12004 | static void perf_event_exit_task_context(struct task_struct *child, int ctxn) |
9b51f66d | 12005 | { |
211de6eb | 12006 | struct perf_event_context *child_ctx, *clone_ctx = NULL; |
63b6da39 | 12007 | struct perf_event *child_event, *next; |
63b6da39 PZ |
12008 | |
12009 | WARN_ON_ONCE(child != current); | |
9b51f66d | 12010 | |
6a3351b6 | 12011 | child_ctx = perf_pin_task_context(child, ctxn); |
63b6da39 | 12012 | if (!child_ctx) |
9b51f66d IM |
12013 | return; |
12014 | ||
ad3a37de | 12015 | /* |
6a3351b6 PZ |
12016 | * In order to reduce the amount of tricky in ctx tear-down, we hold |
12017 | * ctx::mutex over the entire thing. This serializes against almost | |
12018 | * everything that wants to access the ctx. | |
12019 | * | |
12020 | * The exception is sys_perf_event_open() / | |
12021 | * perf_event_create_kernel_count() which does find_get_context() | |
12022 | * without ctx::mutex (it cannot because of the move_group double mutex | |
12023 | * lock thing). See the comments in perf_install_in_context(). | |
ad3a37de | 12024 | */ |
6a3351b6 | 12025 | mutex_lock(&child_ctx->mutex); |
c93f7669 PM |
12026 | |
12027 | /* | |
6a3351b6 PZ |
12028 | * In a single ctx::lock section, de-schedule the events and detach the |
12029 | * context from the task such that we cannot ever get it scheduled back | |
12030 | * in. | |
c93f7669 | 12031 | */ |
6a3351b6 | 12032 | raw_spin_lock_irq(&child_ctx->lock); |
487f05e1 | 12033 | task_ctx_sched_out(__get_cpu_context(child_ctx), child_ctx, EVENT_ALL); |
4a1c0f26 | 12034 | |
71a851b4 | 12035 | /* |
63b6da39 PZ |
12036 | * Now that the context is inactive, destroy the task <-> ctx relation |
12037 | * and mark the context dead. | |
71a851b4 | 12038 | */ |
63b6da39 PZ |
12039 | RCU_INIT_POINTER(child->perf_event_ctxp[ctxn], NULL); |
12040 | put_ctx(child_ctx); /* cannot be last */ | |
12041 | WRITE_ONCE(child_ctx->task, TASK_TOMBSTONE); | |
12042 | put_task_struct(current); /* cannot be last */ | |
4a1c0f26 | 12043 | |
211de6eb | 12044 | clone_ctx = unclone_ctx(child_ctx); |
6a3351b6 | 12045 | raw_spin_unlock_irq(&child_ctx->lock); |
9f498cc5 | 12046 | |
211de6eb PZ |
12047 | if (clone_ctx) |
12048 | put_ctx(clone_ctx); | |
4a1c0f26 | 12049 | |
9f498cc5 | 12050 | /* |
cdd6c482 IM |
12051 | * Report the task dead after unscheduling the events so that we |
12052 | * won't get any samples after PERF_RECORD_EXIT. We can however still | |
12053 | * get a few PERF_RECORD_READ events. | |
9f498cc5 | 12054 | */ |
cdd6c482 | 12055 | perf_event_task(child, child_ctx, 0); |
a63eaf34 | 12056 | |
ebf905fc | 12057 | list_for_each_entry_safe(child_event, next, &child_ctx->event_list, event_entry) |
8ba289b8 | 12058 | perf_event_exit_event(child_event, child_ctx, child); |
8bc20959 | 12059 | |
a63eaf34 PM |
12060 | mutex_unlock(&child_ctx->mutex); |
12061 | ||
12062 | put_ctx(child_ctx); | |
9b51f66d IM |
12063 | } |
12064 | ||
8dc85d54 PZ |
12065 | /* |
12066 | * When a child task exits, feed back event values to parent events. | |
79c9ce57 PZ |
12067 | * |
12068 | * Can be called with cred_guard_mutex held when called from | |
12069 | * install_exec_creds(). | |
8dc85d54 PZ |
12070 | */ |
12071 | void perf_event_exit_task(struct task_struct *child) | |
12072 | { | |
8882135b | 12073 | struct perf_event *event, *tmp; |
8dc85d54 PZ |
12074 | int ctxn; |
12075 | ||
8882135b PZ |
12076 | mutex_lock(&child->perf_event_mutex); |
12077 | list_for_each_entry_safe(event, tmp, &child->perf_event_list, | |
12078 | owner_entry) { | |
12079 | list_del_init(&event->owner_entry); | |
12080 | ||
12081 | /* | |
12082 | * Ensure the list deletion is visible before we clear | |
12083 | * the owner, closes a race against perf_release() where | |
12084 | * we need to serialize on the owner->perf_event_mutex. | |
12085 | */ | |
f47c02c0 | 12086 | smp_store_release(&event->owner, NULL); |
8882135b PZ |
12087 | } |
12088 | mutex_unlock(&child->perf_event_mutex); | |
12089 | ||
8dc85d54 PZ |
12090 | for_each_task_context_nr(ctxn) |
12091 | perf_event_exit_task_context(child, ctxn); | |
4e93ad60 JO |
12092 | |
12093 | /* | |
12094 | * The perf_event_exit_task_context calls perf_event_task | |
12095 | * with child's task_ctx, which generates EXIT events for | |
12096 | * child contexts and sets child->perf_event_ctxp[] to NULL. | |
12097 | * At this point we need to send EXIT events to cpu contexts. | |
12098 | */ | |
12099 | perf_event_task(child, NULL, 0); | |
8dc85d54 PZ |
12100 | } |
12101 | ||
889ff015 FW |
12102 | static void perf_free_event(struct perf_event *event, |
12103 | struct perf_event_context *ctx) | |
12104 | { | |
12105 | struct perf_event *parent = event->parent; | |
12106 | ||
12107 | if (WARN_ON_ONCE(!parent)) | |
12108 | return; | |
12109 | ||
12110 | mutex_lock(&parent->child_mutex); | |
12111 | list_del_init(&event->child_list); | |
12112 | mutex_unlock(&parent->child_mutex); | |
12113 | ||
a6fa941d | 12114 | put_event(parent); |
889ff015 | 12115 | |
652884fe | 12116 | raw_spin_lock_irq(&ctx->lock); |
8a49542c | 12117 | perf_group_detach(event); |
889ff015 | 12118 | list_del_event(event, ctx); |
652884fe | 12119 | raw_spin_unlock_irq(&ctx->lock); |
889ff015 FW |
12120 | free_event(event); |
12121 | } | |
12122 | ||
bbbee908 | 12123 | /* |
1cf8dfe8 PZ |
12124 | * Free a context as created by inheritance by perf_event_init_task() below, |
12125 | * used by fork() in case of fail. | |
652884fe | 12126 | * |
1cf8dfe8 PZ |
12127 | * Even though the task has never lived, the context and events have been |
12128 | * exposed through the child_list, so we must take care tearing it all down. | |
bbbee908 | 12129 | */ |
cdd6c482 | 12130 | void perf_event_free_task(struct task_struct *task) |
bbbee908 | 12131 | { |
8dc85d54 | 12132 | struct perf_event_context *ctx; |
cdd6c482 | 12133 | struct perf_event *event, *tmp; |
8dc85d54 | 12134 | int ctxn; |
bbbee908 | 12135 | |
8dc85d54 PZ |
12136 | for_each_task_context_nr(ctxn) { |
12137 | ctx = task->perf_event_ctxp[ctxn]; | |
12138 | if (!ctx) | |
12139 | continue; | |
bbbee908 | 12140 | |
8dc85d54 | 12141 | mutex_lock(&ctx->mutex); |
e552a838 PZ |
12142 | raw_spin_lock_irq(&ctx->lock); |
12143 | /* | |
12144 | * Destroy the task <-> ctx relation and mark the context dead. | |
12145 | * | |
12146 | * This is important because even though the task hasn't been | |
12147 | * exposed yet the context has been (through child_list). | |
12148 | */ | |
12149 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], NULL); | |
12150 | WRITE_ONCE(ctx->task, TASK_TOMBSTONE); | |
12151 | put_task_struct(task); /* cannot be last */ | |
12152 | raw_spin_unlock_irq(&ctx->lock); | |
bbbee908 | 12153 | |
15121c78 | 12154 | list_for_each_entry_safe(event, tmp, &ctx->event_list, event_entry) |
8dc85d54 | 12155 | perf_free_event(event, ctx); |
bbbee908 | 12156 | |
8dc85d54 | 12157 | mutex_unlock(&ctx->mutex); |
1cf8dfe8 PZ |
12158 | |
12159 | /* | |
12160 | * perf_event_release_kernel() could've stolen some of our | |
12161 | * child events and still have them on its free_list. In that | |
12162 | * case we must wait for these events to have been freed (in | |
12163 | * particular all their references to this task must've been | |
12164 | * dropped). | |
12165 | * | |
12166 | * Without this copy_process() will unconditionally free this | |
12167 | * task (irrespective of its reference count) and | |
12168 | * _free_event()'s put_task_struct(event->hw.target) will be a | |
12169 | * use-after-free. | |
12170 | * | |
12171 | * Wait for all events to drop their context reference. | |
12172 | */ | |
12173 | wait_var_event(&ctx->refcount, refcount_read(&ctx->refcount) == 1); | |
12174 | put_ctx(ctx); /* must be last */ | |
8dc85d54 | 12175 | } |
889ff015 FW |
12176 | } |
12177 | ||
4e231c79 PZ |
12178 | void perf_event_delayed_put(struct task_struct *task) |
12179 | { | |
12180 | int ctxn; | |
12181 | ||
12182 | for_each_task_context_nr(ctxn) | |
12183 | WARN_ON_ONCE(task->perf_event_ctxp[ctxn]); | |
12184 | } | |
12185 | ||
e03e7ee3 | 12186 | struct file *perf_event_get(unsigned int fd) |
ffe8690c | 12187 | { |
02e5ad97 | 12188 | struct file *file = fget(fd); |
e03e7ee3 AS |
12189 | if (!file) |
12190 | return ERR_PTR(-EBADF); | |
ffe8690c | 12191 | |
e03e7ee3 AS |
12192 | if (file->f_op != &perf_fops) { |
12193 | fput(file); | |
12194 | return ERR_PTR(-EBADF); | |
12195 | } | |
ffe8690c | 12196 | |
e03e7ee3 | 12197 | return file; |
ffe8690c KX |
12198 | } |
12199 | ||
f8d959a5 YS |
12200 | const struct perf_event *perf_get_event(struct file *file) |
12201 | { | |
12202 | if (file->f_op != &perf_fops) | |
12203 | return ERR_PTR(-EINVAL); | |
12204 | ||
12205 | return file->private_data; | |
12206 | } | |
12207 | ||
ffe8690c KX |
12208 | const struct perf_event_attr *perf_event_attrs(struct perf_event *event) |
12209 | { | |
12210 | if (!event) | |
12211 | return ERR_PTR(-EINVAL); | |
12212 | ||
12213 | return &event->attr; | |
12214 | } | |
12215 | ||
97dee4f3 | 12216 | /* |
788faab7 | 12217 | * Inherit an event from parent task to child task. |
d8a8cfc7 PZ |
12218 | * |
12219 | * Returns: | |
12220 | * - valid pointer on success | |
12221 | * - NULL for orphaned events | |
12222 | * - IS_ERR() on error | |
97dee4f3 PZ |
12223 | */ |
12224 | static struct perf_event * | |
12225 | inherit_event(struct perf_event *parent_event, | |
12226 | struct task_struct *parent, | |
12227 | struct perf_event_context *parent_ctx, | |
12228 | struct task_struct *child, | |
12229 | struct perf_event *group_leader, | |
12230 | struct perf_event_context *child_ctx) | |
12231 | { | |
8ca2bd41 | 12232 | enum perf_event_state parent_state = parent_event->state; |
97dee4f3 | 12233 | struct perf_event *child_event; |
cee010ec | 12234 | unsigned long flags; |
97dee4f3 PZ |
12235 | |
12236 | /* | |
12237 | * Instead of creating recursive hierarchies of events, | |
12238 | * we link inherited events back to the original parent, | |
12239 | * which has a filp for sure, which we use as the reference | |
12240 | * count: | |
12241 | */ | |
12242 | if (parent_event->parent) | |
12243 | parent_event = parent_event->parent; | |
12244 | ||
12245 | child_event = perf_event_alloc(&parent_event->attr, | |
12246 | parent_event->cpu, | |
d580ff86 | 12247 | child, |
97dee4f3 | 12248 | group_leader, parent_event, |
79dff51e | 12249 | NULL, NULL, -1); |
97dee4f3 PZ |
12250 | if (IS_ERR(child_event)) |
12251 | return child_event; | |
a6fa941d | 12252 | |
313ccb96 JO |
12253 | |
12254 | if ((child_event->attach_state & PERF_ATTACH_TASK_DATA) && | |
12255 | !child_ctx->task_ctx_data) { | |
12256 | struct pmu *pmu = child_event->pmu; | |
12257 | ||
12258 | child_ctx->task_ctx_data = kzalloc(pmu->task_ctx_size, | |
12259 | GFP_KERNEL); | |
12260 | if (!child_ctx->task_ctx_data) { | |
12261 | free_event(child_event); | |
697d8778 | 12262 | return ERR_PTR(-ENOMEM); |
313ccb96 JO |
12263 | } |
12264 | } | |
12265 | ||
c6e5b732 PZ |
12266 | /* |
12267 | * is_orphaned_event() and list_add_tail(&parent_event->child_list) | |
12268 | * must be under the same lock in order to serialize against | |
12269 | * perf_event_release_kernel(), such that either we must observe | |
12270 | * is_orphaned_event() or they will observe us on the child_list. | |
12271 | */ | |
12272 | mutex_lock(&parent_event->child_mutex); | |
fadfe7be JO |
12273 | if (is_orphaned_event(parent_event) || |
12274 | !atomic_long_inc_not_zero(&parent_event->refcount)) { | |
c6e5b732 | 12275 | mutex_unlock(&parent_event->child_mutex); |
313ccb96 | 12276 | /* task_ctx_data is freed with child_ctx */ |
a6fa941d AV |
12277 | free_event(child_event); |
12278 | return NULL; | |
12279 | } | |
12280 | ||
97dee4f3 PZ |
12281 | get_ctx(child_ctx); |
12282 | ||
12283 | /* | |
12284 | * Make the child state follow the state of the parent event, | |
12285 | * not its attr.disabled bit. We hold the parent's mutex, | |
12286 | * so we won't race with perf_event_{en, dis}able_family. | |
12287 | */ | |
1929def9 | 12288 | if (parent_state >= PERF_EVENT_STATE_INACTIVE) |
97dee4f3 PZ |
12289 | child_event->state = PERF_EVENT_STATE_INACTIVE; |
12290 | else | |
12291 | child_event->state = PERF_EVENT_STATE_OFF; | |
12292 | ||
12293 | if (parent_event->attr.freq) { | |
12294 | u64 sample_period = parent_event->hw.sample_period; | |
12295 | struct hw_perf_event *hwc = &child_event->hw; | |
12296 | ||
12297 | hwc->sample_period = sample_period; | |
12298 | hwc->last_period = sample_period; | |
12299 | ||
12300 | local64_set(&hwc->period_left, sample_period); | |
12301 | } | |
12302 | ||
12303 | child_event->ctx = child_ctx; | |
12304 | child_event->overflow_handler = parent_event->overflow_handler; | |
4dc0da86 AK |
12305 | child_event->overflow_handler_context |
12306 | = parent_event->overflow_handler_context; | |
97dee4f3 | 12307 | |
614b6780 TG |
12308 | /* |
12309 | * Precalculate sample_data sizes | |
12310 | */ | |
12311 | perf_event__header_size(child_event); | |
6844c09d | 12312 | perf_event__id_header_size(child_event); |
614b6780 | 12313 | |
97dee4f3 PZ |
12314 | /* |
12315 | * Link it up in the child's context: | |
12316 | */ | |
cee010ec | 12317 | raw_spin_lock_irqsave(&child_ctx->lock, flags); |
97dee4f3 | 12318 | add_event_to_ctx(child_event, child_ctx); |
cee010ec | 12319 | raw_spin_unlock_irqrestore(&child_ctx->lock, flags); |
97dee4f3 | 12320 | |
97dee4f3 PZ |
12321 | /* |
12322 | * Link this into the parent event's child list | |
12323 | */ | |
97dee4f3 PZ |
12324 | list_add_tail(&child_event->child_list, &parent_event->child_list); |
12325 | mutex_unlock(&parent_event->child_mutex); | |
12326 | ||
12327 | return child_event; | |
12328 | } | |
12329 | ||
d8a8cfc7 PZ |
12330 | /* |
12331 | * Inherits an event group. | |
12332 | * | |
12333 | * This will quietly suppress orphaned events; !inherit_event() is not an error. | |
12334 | * This matches with perf_event_release_kernel() removing all child events. | |
12335 | * | |
12336 | * Returns: | |
12337 | * - 0 on success | |
12338 | * - <0 on error | |
12339 | */ | |
97dee4f3 PZ |
12340 | static int inherit_group(struct perf_event *parent_event, |
12341 | struct task_struct *parent, | |
12342 | struct perf_event_context *parent_ctx, | |
12343 | struct task_struct *child, | |
12344 | struct perf_event_context *child_ctx) | |
12345 | { | |
12346 | struct perf_event *leader; | |
12347 | struct perf_event *sub; | |
12348 | struct perf_event *child_ctr; | |
12349 | ||
12350 | leader = inherit_event(parent_event, parent, parent_ctx, | |
12351 | child, NULL, child_ctx); | |
12352 | if (IS_ERR(leader)) | |
12353 | return PTR_ERR(leader); | |
d8a8cfc7 PZ |
12354 | /* |
12355 | * @leader can be NULL here because of is_orphaned_event(). In this | |
12356 | * case inherit_event() will create individual events, similar to what | |
12357 | * perf_group_detach() would do anyway. | |
12358 | */ | |
edb39592 | 12359 | for_each_sibling_event(sub, parent_event) { |
97dee4f3 PZ |
12360 | child_ctr = inherit_event(sub, parent, parent_ctx, |
12361 | child, leader, child_ctx); | |
12362 | if (IS_ERR(child_ctr)) | |
12363 | return PTR_ERR(child_ctr); | |
f733c6b5 | 12364 | |
00496fe5 | 12365 | if (sub->aux_event == parent_event && child_ctr && |
f733c6b5 AS |
12366 | !perf_get_aux_event(child_ctr, leader)) |
12367 | return -EINVAL; | |
97dee4f3 PZ |
12368 | } |
12369 | return 0; | |
889ff015 FW |
12370 | } |
12371 | ||
d8a8cfc7 PZ |
12372 | /* |
12373 | * Creates the child task context and tries to inherit the event-group. | |
12374 | * | |
12375 | * Clears @inherited_all on !attr.inherited or error. Note that we'll leave | |
12376 | * inherited_all set when we 'fail' to inherit an orphaned event; this is | |
12377 | * consistent with perf_event_release_kernel() removing all child events. | |
12378 | * | |
12379 | * Returns: | |
12380 | * - 0 on success | |
12381 | * - <0 on error | |
12382 | */ | |
889ff015 FW |
12383 | static int |
12384 | inherit_task_group(struct perf_event *event, struct task_struct *parent, | |
12385 | struct perf_event_context *parent_ctx, | |
8dc85d54 | 12386 | struct task_struct *child, int ctxn, |
889ff015 FW |
12387 | int *inherited_all) |
12388 | { | |
12389 | int ret; | |
8dc85d54 | 12390 | struct perf_event_context *child_ctx; |
889ff015 FW |
12391 | |
12392 | if (!event->attr.inherit) { | |
12393 | *inherited_all = 0; | |
12394 | return 0; | |
bbbee908 PZ |
12395 | } |
12396 | ||
fe4b04fa | 12397 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 FW |
12398 | if (!child_ctx) { |
12399 | /* | |
12400 | * This is executed from the parent task context, so | |
12401 | * inherit events that have been marked for cloning. | |
12402 | * First allocate and initialize a context for the | |
12403 | * child. | |
12404 | */ | |
734df5ab | 12405 | child_ctx = alloc_perf_context(parent_ctx->pmu, child); |
889ff015 FW |
12406 | if (!child_ctx) |
12407 | return -ENOMEM; | |
bbbee908 | 12408 | |
8dc85d54 | 12409 | child->perf_event_ctxp[ctxn] = child_ctx; |
889ff015 FW |
12410 | } |
12411 | ||
12412 | ret = inherit_group(event, parent, parent_ctx, | |
12413 | child, child_ctx); | |
12414 | ||
12415 | if (ret) | |
12416 | *inherited_all = 0; | |
12417 | ||
12418 | return ret; | |
bbbee908 PZ |
12419 | } |
12420 | ||
9b51f66d | 12421 | /* |
cdd6c482 | 12422 | * Initialize the perf_event context in task_struct |
9b51f66d | 12423 | */ |
985c8dcb | 12424 | static int perf_event_init_context(struct task_struct *child, int ctxn) |
9b51f66d | 12425 | { |
889ff015 | 12426 | struct perf_event_context *child_ctx, *parent_ctx; |
cdd6c482 IM |
12427 | struct perf_event_context *cloned_ctx; |
12428 | struct perf_event *event; | |
9b51f66d | 12429 | struct task_struct *parent = current; |
564c2b21 | 12430 | int inherited_all = 1; |
dddd3379 | 12431 | unsigned long flags; |
6ab423e0 | 12432 | int ret = 0; |
9b51f66d | 12433 | |
8dc85d54 | 12434 | if (likely(!parent->perf_event_ctxp[ctxn])) |
6ab423e0 PZ |
12435 | return 0; |
12436 | ||
ad3a37de | 12437 | /* |
25346b93 PM |
12438 | * If the parent's context is a clone, pin it so it won't get |
12439 | * swapped under us. | |
ad3a37de | 12440 | */ |
8dc85d54 | 12441 | parent_ctx = perf_pin_task_context(parent, ctxn); |
ffb4ef21 PZ |
12442 | if (!parent_ctx) |
12443 | return 0; | |
25346b93 | 12444 | |
ad3a37de PM |
12445 | /* |
12446 | * No need to check if parent_ctx != NULL here; since we saw | |
12447 | * it non-NULL earlier, the only reason for it to become NULL | |
12448 | * is if we exit, and since we're currently in the middle of | |
12449 | * a fork we can't be exiting at the same time. | |
12450 | */ | |
ad3a37de | 12451 | |
9b51f66d IM |
12452 | /* |
12453 | * Lock the parent list. No need to lock the child - not PID | |
12454 | * hashed yet and not running, so nobody can access it. | |
12455 | */ | |
d859e29f | 12456 | mutex_lock(&parent_ctx->mutex); |
9b51f66d IM |
12457 | |
12458 | /* | |
12459 | * We dont have to disable NMIs - we are only looking at | |
12460 | * the list, not manipulating it: | |
12461 | */ | |
6e6804d2 | 12462 | perf_event_groups_for_each(event, &parent_ctx->pinned_groups) { |
8dc85d54 PZ |
12463 | ret = inherit_task_group(event, parent, parent_ctx, |
12464 | child, ctxn, &inherited_all); | |
889ff015 | 12465 | if (ret) |
e7cc4865 | 12466 | goto out_unlock; |
889ff015 | 12467 | } |
b93f7978 | 12468 | |
dddd3379 TG |
12469 | /* |
12470 | * We can't hold ctx->lock when iterating the ->flexible_group list due | |
12471 | * to allocations, but we need to prevent rotation because | |
12472 | * rotate_ctx() will change the list from interrupt context. | |
12473 | */ | |
12474 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); | |
12475 | parent_ctx->rotate_disable = 1; | |
12476 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); | |
12477 | ||
6e6804d2 | 12478 | perf_event_groups_for_each(event, &parent_ctx->flexible_groups) { |
8dc85d54 PZ |
12479 | ret = inherit_task_group(event, parent, parent_ctx, |
12480 | child, ctxn, &inherited_all); | |
889ff015 | 12481 | if (ret) |
e7cc4865 | 12482 | goto out_unlock; |
564c2b21 PM |
12483 | } |
12484 | ||
dddd3379 TG |
12485 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); |
12486 | parent_ctx->rotate_disable = 0; | |
dddd3379 | 12487 | |
8dc85d54 | 12488 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 | 12489 | |
05cbaa28 | 12490 | if (child_ctx && inherited_all) { |
564c2b21 PM |
12491 | /* |
12492 | * Mark the child context as a clone of the parent | |
12493 | * context, or of whatever the parent is a clone of. | |
c5ed5145 PZ |
12494 | * |
12495 | * Note that if the parent is a clone, the holding of | |
12496 | * parent_ctx->lock avoids it from being uncloned. | |
564c2b21 | 12497 | */ |
c5ed5145 | 12498 | cloned_ctx = parent_ctx->parent_ctx; |
ad3a37de PM |
12499 | if (cloned_ctx) { |
12500 | child_ctx->parent_ctx = cloned_ctx; | |
25346b93 | 12501 | child_ctx->parent_gen = parent_ctx->parent_gen; |
564c2b21 PM |
12502 | } else { |
12503 | child_ctx->parent_ctx = parent_ctx; | |
12504 | child_ctx->parent_gen = parent_ctx->generation; | |
12505 | } | |
12506 | get_ctx(child_ctx->parent_ctx); | |
9b51f66d IM |
12507 | } |
12508 | ||
c5ed5145 | 12509 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); |
e7cc4865 | 12510 | out_unlock: |
d859e29f | 12511 | mutex_unlock(&parent_ctx->mutex); |
6ab423e0 | 12512 | |
25346b93 | 12513 | perf_unpin_context(parent_ctx); |
fe4b04fa | 12514 | put_ctx(parent_ctx); |
ad3a37de | 12515 | |
6ab423e0 | 12516 | return ret; |
9b51f66d IM |
12517 | } |
12518 | ||
8dc85d54 PZ |
12519 | /* |
12520 | * Initialize the perf_event context in task_struct | |
12521 | */ | |
12522 | int perf_event_init_task(struct task_struct *child) | |
12523 | { | |
12524 | int ctxn, ret; | |
12525 | ||
8550d7cb ON |
12526 | memset(child->perf_event_ctxp, 0, sizeof(child->perf_event_ctxp)); |
12527 | mutex_init(&child->perf_event_mutex); | |
12528 | INIT_LIST_HEAD(&child->perf_event_list); | |
12529 | ||
8dc85d54 PZ |
12530 | for_each_task_context_nr(ctxn) { |
12531 | ret = perf_event_init_context(child, ctxn); | |
6c72e350 PZ |
12532 | if (ret) { |
12533 | perf_event_free_task(child); | |
8dc85d54 | 12534 | return ret; |
6c72e350 | 12535 | } |
8dc85d54 PZ |
12536 | } |
12537 | ||
12538 | return 0; | |
12539 | } | |
12540 | ||
220b140b PM |
12541 | static void __init perf_event_init_all_cpus(void) |
12542 | { | |
b28ab83c | 12543 | struct swevent_htable *swhash; |
220b140b | 12544 | int cpu; |
220b140b | 12545 | |
a63fbed7 TG |
12546 | zalloc_cpumask_var(&perf_online_mask, GFP_KERNEL); |
12547 | ||
220b140b | 12548 | for_each_possible_cpu(cpu) { |
b28ab83c PZ |
12549 | swhash = &per_cpu(swevent_htable, cpu); |
12550 | mutex_init(&swhash->hlist_mutex); | |
2fde4f94 | 12551 | INIT_LIST_HEAD(&per_cpu(active_ctx_list, cpu)); |
f2fb6bef KL |
12552 | |
12553 | INIT_LIST_HEAD(&per_cpu(pmu_sb_events.list, cpu)); | |
12554 | raw_spin_lock_init(&per_cpu(pmu_sb_events.lock, cpu)); | |
e48c1788 | 12555 | |
058fe1c0 DCC |
12556 | #ifdef CONFIG_CGROUP_PERF |
12557 | INIT_LIST_HEAD(&per_cpu(cgrp_cpuctx_list, cpu)); | |
12558 | #endif | |
e48c1788 | 12559 | INIT_LIST_HEAD(&per_cpu(sched_cb_list, cpu)); |
220b140b PM |
12560 | } |
12561 | } | |
12562 | ||
d18bf422 | 12563 | static void perf_swevent_init_cpu(unsigned int cpu) |
0793a61d | 12564 | { |
108b02cf | 12565 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
0793a61d | 12566 | |
b28ab83c | 12567 | mutex_lock(&swhash->hlist_mutex); |
059fcd8c | 12568 | if (swhash->hlist_refcount > 0 && !swevent_hlist_deref(swhash)) { |
76e1d904 FW |
12569 | struct swevent_hlist *hlist; |
12570 | ||
b28ab83c PZ |
12571 | hlist = kzalloc_node(sizeof(*hlist), GFP_KERNEL, cpu_to_node(cpu)); |
12572 | WARN_ON(!hlist); | |
12573 | rcu_assign_pointer(swhash->swevent_hlist, hlist); | |
76e1d904 | 12574 | } |
b28ab83c | 12575 | mutex_unlock(&swhash->hlist_mutex); |
0793a61d TG |
12576 | } |
12577 | ||
2965faa5 | 12578 | #if defined CONFIG_HOTPLUG_CPU || defined CONFIG_KEXEC_CORE |
108b02cf | 12579 | static void __perf_event_exit_context(void *__info) |
0793a61d | 12580 | { |
108b02cf | 12581 | struct perf_event_context *ctx = __info; |
fae3fde6 PZ |
12582 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
12583 | struct perf_event *event; | |
0793a61d | 12584 | |
fae3fde6 | 12585 | raw_spin_lock(&ctx->lock); |
0ee098c9 | 12586 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
fae3fde6 | 12587 | list_for_each_entry(event, &ctx->event_list, event_entry) |
45a0e07a | 12588 | __perf_remove_from_context(event, cpuctx, ctx, (void *)DETACH_GROUP); |
fae3fde6 | 12589 | raw_spin_unlock(&ctx->lock); |
0793a61d | 12590 | } |
108b02cf PZ |
12591 | |
12592 | static void perf_event_exit_cpu_context(int cpu) | |
12593 | { | |
a63fbed7 | 12594 | struct perf_cpu_context *cpuctx; |
108b02cf PZ |
12595 | struct perf_event_context *ctx; |
12596 | struct pmu *pmu; | |
108b02cf | 12597 | |
a63fbed7 TG |
12598 | mutex_lock(&pmus_lock); |
12599 | list_for_each_entry(pmu, &pmus, entry) { | |
12600 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
12601 | ctx = &cpuctx->ctx; | |
108b02cf PZ |
12602 | |
12603 | mutex_lock(&ctx->mutex); | |
12604 | smp_call_function_single(cpu, __perf_event_exit_context, ctx, 1); | |
a63fbed7 | 12605 | cpuctx->online = 0; |
108b02cf PZ |
12606 | mutex_unlock(&ctx->mutex); |
12607 | } | |
a63fbed7 TG |
12608 | cpumask_clear_cpu(cpu, perf_online_mask); |
12609 | mutex_unlock(&pmus_lock); | |
108b02cf | 12610 | } |
00e16c3d TG |
12611 | #else |
12612 | ||
12613 | static void perf_event_exit_cpu_context(int cpu) { } | |
12614 | ||
12615 | #endif | |
108b02cf | 12616 | |
a63fbed7 TG |
12617 | int perf_event_init_cpu(unsigned int cpu) |
12618 | { | |
12619 | struct perf_cpu_context *cpuctx; | |
12620 | struct perf_event_context *ctx; | |
12621 | struct pmu *pmu; | |
12622 | ||
12623 | perf_swevent_init_cpu(cpu); | |
12624 | ||
12625 | mutex_lock(&pmus_lock); | |
12626 | cpumask_set_cpu(cpu, perf_online_mask); | |
12627 | list_for_each_entry(pmu, &pmus, entry) { | |
12628 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
12629 | ctx = &cpuctx->ctx; | |
12630 | ||
12631 | mutex_lock(&ctx->mutex); | |
12632 | cpuctx->online = 1; | |
12633 | mutex_unlock(&ctx->mutex); | |
12634 | } | |
12635 | mutex_unlock(&pmus_lock); | |
12636 | ||
12637 | return 0; | |
12638 | } | |
12639 | ||
00e16c3d | 12640 | int perf_event_exit_cpu(unsigned int cpu) |
0793a61d | 12641 | { |
e3703f8c | 12642 | perf_event_exit_cpu_context(cpu); |
00e16c3d | 12643 | return 0; |
0793a61d | 12644 | } |
0793a61d | 12645 | |
c277443c PZ |
12646 | static int |
12647 | perf_reboot(struct notifier_block *notifier, unsigned long val, void *v) | |
12648 | { | |
12649 | int cpu; | |
12650 | ||
12651 | for_each_online_cpu(cpu) | |
12652 | perf_event_exit_cpu(cpu); | |
12653 | ||
12654 | return NOTIFY_OK; | |
12655 | } | |
12656 | ||
12657 | /* | |
12658 | * Run the perf reboot notifier at the very last possible moment so that | |
12659 | * the generic watchdog code runs as long as possible. | |
12660 | */ | |
12661 | static struct notifier_block perf_reboot_notifier = { | |
12662 | .notifier_call = perf_reboot, | |
12663 | .priority = INT_MIN, | |
12664 | }; | |
12665 | ||
cdd6c482 | 12666 | void __init perf_event_init(void) |
0793a61d | 12667 | { |
3c502e7a JW |
12668 | int ret; |
12669 | ||
2e80a82a PZ |
12670 | idr_init(&pmu_idr); |
12671 | ||
220b140b | 12672 | perf_event_init_all_cpus(); |
b0a873eb | 12673 | init_srcu_struct(&pmus_srcu); |
2e80a82a PZ |
12674 | perf_pmu_register(&perf_swevent, "software", PERF_TYPE_SOFTWARE); |
12675 | perf_pmu_register(&perf_cpu_clock, NULL, -1); | |
12676 | perf_pmu_register(&perf_task_clock, NULL, -1); | |
b0a873eb | 12677 | perf_tp_register(); |
00e16c3d | 12678 | perf_event_init_cpu(smp_processor_id()); |
c277443c | 12679 | register_reboot_notifier(&perf_reboot_notifier); |
3c502e7a JW |
12680 | |
12681 | ret = init_hw_breakpoint(); | |
12682 | WARN(ret, "hw_breakpoint initialization failed with: %d", ret); | |
b2029520 | 12683 | |
b01c3a00 JO |
12684 | /* |
12685 | * Build time assertion that we keep the data_head at the intended | |
12686 | * location. IOW, validation we got the __reserved[] size right. | |
12687 | */ | |
12688 | BUILD_BUG_ON((offsetof(struct perf_event_mmap_page, data_head)) | |
12689 | != 1024); | |
0793a61d | 12690 | } |
abe43400 | 12691 | |
fd979c01 CS |
12692 | ssize_t perf_event_sysfs_show(struct device *dev, struct device_attribute *attr, |
12693 | char *page) | |
12694 | { | |
12695 | struct perf_pmu_events_attr *pmu_attr = | |
12696 | container_of(attr, struct perf_pmu_events_attr, attr); | |
12697 | ||
12698 | if (pmu_attr->event_str) | |
12699 | return sprintf(page, "%s\n", pmu_attr->event_str); | |
12700 | ||
12701 | return 0; | |
12702 | } | |
675965b0 | 12703 | EXPORT_SYMBOL_GPL(perf_event_sysfs_show); |
fd979c01 | 12704 | |
abe43400 PZ |
12705 | static int __init perf_event_sysfs_init(void) |
12706 | { | |
12707 | struct pmu *pmu; | |
12708 | int ret; | |
12709 | ||
12710 | mutex_lock(&pmus_lock); | |
12711 | ||
12712 | ret = bus_register(&pmu_bus); | |
12713 | if (ret) | |
12714 | goto unlock; | |
12715 | ||
12716 | list_for_each_entry(pmu, &pmus, entry) { | |
12717 | if (!pmu->name || pmu->type < 0) | |
12718 | continue; | |
12719 | ||
12720 | ret = pmu_dev_alloc(pmu); | |
12721 | WARN(ret, "Failed to register pmu: %s, reason %d\n", pmu->name, ret); | |
12722 | } | |
12723 | pmu_bus_running = 1; | |
12724 | ret = 0; | |
12725 | ||
12726 | unlock: | |
12727 | mutex_unlock(&pmus_lock); | |
12728 | ||
12729 | return ret; | |
12730 | } | |
12731 | device_initcall(perf_event_sysfs_init); | |
e5d1367f SE |
12732 | |
12733 | #ifdef CONFIG_CGROUP_PERF | |
eb95419b TH |
12734 | static struct cgroup_subsys_state * |
12735 | perf_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) | |
e5d1367f SE |
12736 | { |
12737 | struct perf_cgroup *jc; | |
e5d1367f | 12738 | |
1b15d055 | 12739 | jc = kzalloc(sizeof(*jc), GFP_KERNEL); |
e5d1367f SE |
12740 | if (!jc) |
12741 | return ERR_PTR(-ENOMEM); | |
12742 | ||
e5d1367f SE |
12743 | jc->info = alloc_percpu(struct perf_cgroup_info); |
12744 | if (!jc->info) { | |
12745 | kfree(jc); | |
12746 | return ERR_PTR(-ENOMEM); | |
12747 | } | |
12748 | ||
e5d1367f SE |
12749 | return &jc->css; |
12750 | } | |
12751 | ||
eb95419b | 12752 | static void perf_cgroup_css_free(struct cgroup_subsys_state *css) |
e5d1367f | 12753 | { |
eb95419b TH |
12754 | struct perf_cgroup *jc = container_of(css, struct perf_cgroup, css); |
12755 | ||
e5d1367f SE |
12756 | free_percpu(jc->info); |
12757 | kfree(jc); | |
12758 | } | |
12759 | ||
12760 | static int __perf_cgroup_move(void *info) | |
12761 | { | |
12762 | struct task_struct *task = info; | |
ddaaf4e2 | 12763 | rcu_read_lock(); |
e5d1367f | 12764 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT | PERF_CGROUP_SWIN); |
ddaaf4e2 | 12765 | rcu_read_unlock(); |
e5d1367f SE |
12766 | return 0; |
12767 | } | |
12768 | ||
1f7dd3e5 | 12769 | static void perf_cgroup_attach(struct cgroup_taskset *tset) |
e5d1367f | 12770 | { |
bb9d97b6 | 12771 | struct task_struct *task; |
1f7dd3e5 | 12772 | struct cgroup_subsys_state *css; |
bb9d97b6 | 12773 | |
1f7dd3e5 | 12774 | cgroup_taskset_for_each(task, css, tset) |
bb9d97b6 | 12775 | task_function_call(task, __perf_cgroup_move, task); |
e5d1367f SE |
12776 | } |
12777 | ||
073219e9 | 12778 | struct cgroup_subsys perf_event_cgrp_subsys = { |
92fb9748 TH |
12779 | .css_alloc = perf_cgroup_css_alloc, |
12780 | .css_free = perf_cgroup_css_free, | |
bb9d97b6 | 12781 | .attach = perf_cgroup_attach, |
968ebff1 TH |
12782 | /* |
12783 | * Implicitly enable on dfl hierarchy so that perf events can | |
12784 | * always be filtered by cgroup2 path as long as perf_event | |
12785 | * controller is not mounted on a legacy hierarchy. | |
12786 | */ | |
12787 | .implicit_on_dfl = true, | |
8cfd8147 | 12788 | .threaded = true, |
e5d1367f SE |
12789 | }; |
12790 | #endif /* CONFIG_CGROUP_PERF */ |