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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> | |
0793a61d | 52 | |
76369139 FW |
53 | #include "internal.h" |
54 | ||
4e193bd4 TB |
55 | #include <asm/irq_regs.h> |
56 | ||
272325c4 PZ |
57 | typedef int (*remote_function_f)(void *); |
58 | ||
fe4b04fa | 59 | struct remote_function_call { |
e7e7ee2e | 60 | struct task_struct *p; |
272325c4 | 61 | remote_function_f func; |
e7e7ee2e IM |
62 | void *info; |
63 | int ret; | |
fe4b04fa PZ |
64 | }; |
65 | ||
66 | static void remote_function(void *data) | |
67 | { | |
68 | struct remote_function_call *tfc = data; | |
69 | struct task_struct *p = tfc->p; | |
70 | ||
71 | if (p) { | |
0da4cf3e PZ |
72 | /* -EAGAIN */ |
73 | if (task_cpu(p) != smp_processor_id()) | |
74 | return; | |
75 | ||
76 | /* | |
77 | * Now that we're on right CPU with IRQs disabled, we can test | |
78 | * if we hit the right task without races. | |
79 | */ | |
80 | ||
81 | tfc->ret = -ESRCH; /* No such (running) process */ | |
82 | if (p != current) | |
fe4b04fa PZ |
83 | return; |
84 | } | |
85 | ||
86 | tfc->ret = tfc->func(tfc->info); | |
87 | } | |
88 | ||
89 | /** | |
90 | * task_function_call - call a function on the cpu on which a task runs | |
91 | * @p: the task to evaluate | |
92 | * @func: the function to be called | |
93 | * @info: the function call argument | |
94 | * | |
95 | * Calls the function @func when the task is currently running. This might | |
96 | * be on the current CPU, which just calls the function directly | |
97 | * | |
98 | * returns: @func return value, or | |
99 | * -ESRCH - when the process isn't running | |
100 | * -EAGAIN - when the process moved away | |
101 | */ | |
102 | static int | |
272325c4 | 103 | task_function_call(struct task_struct *p, remote_function_f func, void *info) |
fe4b04fa PZ |
104 | { |
105 | struct remote_function_call data = { | |
e7e7ee2e IM |
106 | .p = p, |
107 | .func = func, | |
108 | .info = info, | |
0da4cf3e | 109 | .ret = -EAGAIN, |
fe4b04fa | 110 | }; |
0da4cf3e | 111 | int ret; |
fe4b04fa | 112 | |
0da4cf3e PZ |
113 | do { |
114 | ret = smp_call_function_single(task_cpu(p), remote_function, &data, 1); | |
115 | if (!ret) | |
116 | ret = data.ret; | |
117 | } while (ret == -EAGAIN); | |
fe4b04fa | 118 | |
0da4cf3e | 119 | return ret; |
fe4b04fa PZ |
120 | } |
121 | ||
122 | /** | |
123 | * cpu_function_call - call a function on the cpu | |
124 | * @func: the function to be called | |
125 | * @info: the function call argument | |
126 | * | |
127 | * Calls the function @func on the remote cpu. | |
128 | * | |
129 | * returns: @func return value or -ENXIO when the cpu is offline | |
130 | */ | |
272325c4 | 131 | static int cpu_function_call(int cpu, remote_function_f func, void *info) |
fe4b04fa PZ |
132 | { |
133 | struct remote_function_call data = { | |
e7e7ee2e IM |
134 | .p = NULL, |
135 | .func = func, | |
136 | .info = info, | |
137 | .ret = -ENXIO, /* No such CPU */ | |
fe4b04fa PZ |
138 | }; |
139 | ||
140 | smp_call_function_single(cpu, remote_function, &data, 1); | |
141 | ||
142 | return data.ret; | |
143 | } | |
144 | ||
fae3fde6 PZ |
145 | static inline struct perf_cpu_context * |
146 | __get_cpu_context(struct perf_event_context *ctx) | |
147 | { | |
148 | return this_cpu_ptr(ctx->pmu->pmu_cpu_context); | |
149 | } | |
150 | ||
151 | static void perf_ctx_lock(struct perf_cpu_context *cpuctx, | |
152 | struct perf_event_context *ctx) | |
0017960f | 153 | { |
fae3fde6 PZ |
154 | raw_spin_lock(&cpuctx->ctx.lock); |
155 | if (ctx) | |
156 | raw_spin_lock(&ctx->lock); | |
157 | } | |
158 | ||
159 | static void perf_ctx_unlock(struct perf_cpu_context *cpuctx, | |
160 | struct perf_event_context *ctx) | |
161 | { | |
162 | if (ctx) | |
163 | raw_spin_unlock(&ctx->lock); | |
164 | raw_spin_unlock(&cpuctx->ctx.lock); | |
165 | } | |
166 | ||
63b6da39 PZ |
167 | #define TASK_TOMBSTONE ((void *)-1L) |
168 | ||
169 | static bool is_kernel_event(struct perf_event *event) | |
170 | { | |
f47c02c0 | 171 | return READ_ONCE(event->owner) == TASK_TOMBSTONE; |
63b6da39 PZ |
172 | } |
173 | ||
39a43640 PZ |
174 | /* |
175 | * On task ctx scheduling... | |
176 | * | |
177 | * When !ctx->nr_events a task context will not be scheduled. This means | |
178 | * we can disable the scheduler hooks (for performance) without leaving | |
179 | * pending task ctx state. | |
180 | * | |
181 | * This however results in two special cases: | |
182 | * | |
183 | * - removing the last event from a task ctx; this is relatively straight | |
184 | * forward and is done in __perf_remove_from_context. | |
185 | * | |
186 | * - adding the first event to a task ctx; this is tricky because we cannot | |
187 | * rely on ctx->is_active and therefore cannot use event_function_call(). | |
188 | * See perf_install_in_context(). | |
189 | * | |
39a43640 PZ |
190 | * If ctx->nr_events, then ctx->is_active and cpuctx->task_ctx are set. |
191 | */ | |
192 | ||
fae3fde6 PZ |
193 | typedef void (*event_f)(struct perf_event *, struct perf_cpu_context *, |
194 | struct perf_event_context *, void *); | |
195 | ||
196 | struct event_function_struct { | |
197 | struct perf_event *event; | |
198 | event_f func; | |
199 | void *data; | |
200 | }; | |
201 | ||
202 | static int event_function(void *info) | |
203 | { | |
204 | struct event_function_struct *efs = info; | |
205 | struct perf_event *event = efs->event; | |
0017960f | 206 | struct perf_event_context *ctx = event->ctx; |
fae3fde6 PZ |
207 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
208 | struct perf_event_context *task_ctx = cpuctx->task_ctx; | |
63b6da39 | 209 | int ret = 0; |
fae3fde6 | 210 | |
16444645 | 211 | lockdep_assert_irqs_disabled(); |
fae3fde6 | 212 | |
63b6da39 | 213 | perf_ctx_lock(cpuctx, task_ctx); |
fae3fde6 PZ |
214 | /* |
215 | * Since we do the IPI call without holding ctx->lock things can have | |
216 | * changed, double check we hit the task we set out to hit. | |
fae3fde6 PZ |
217 | */ |
218 | if (ctx->task) { | |
63b6da39 | 219 | if (ctx->task != current) { |
0da4cf3e | 220 | ret = -ESRCH; |
63b6da39 PZ |
221 | goto unlock; |
222 | } | |
fae3fde6 | 223 | |
fae3fde6 PZ |
224 | /* |
225 | * We only use event_function_call() on established contexts, | |
226 | * and event_function() is only ever called when active (or | |
227 | * rather, we'll have bailed in task_function_call() or the | |
228 | * above ctx->task != current test), therefore we must have | |
229 | * ctx->is_active here. | |
230 | */ | |
231 | WARN_ON_ONCE(!ctx->is_active); | |
232 | /* | |
233 | * And since we have ctx->is_active, cpuctx->task_ctx must | |
234 | * match. | |
235 | */ | |
63b6da39 PZ |
236 | WARN_ON_ONCE(task_ctx != ctx); |
237 | } else { | |
238 | WARN_ON_ONCE(&cpuctx->ctx != ctx); | |
fae3fde6 | 239 | } |
63b6da39 | 240 | |
fae3fde6 | 241 | efs->func(event, cpuctx, ctx, efs->data); |
63b6da39 | 242 | unlock: |
fae3fde6 PZ |
243 | perf_ctx_unlock(cpuctx, task_ctx); |
244 | ||
63b6da39 | 245 | return ret; |
fae3fde6 PZ |
246 | } |
247 | ||
fae3fde6 | 248 | static void event_function_call(struct perf_event *event, event_f func, void *data) |
0017960f PZ |
249 | { |
250 | struct perf_event_context *ctx = event->ctx; | |
63b6da39 | 251 | struct task_struct *task = READ_ONCE(ctx->task); /* verified in event_function */ |
fae3fde6 PZ |
252 | struct event_function_struct efs = { |
253 | .event = event, | |
254 | .func = func, | |
255 | .data = data, | |
256 | }; | |
0017960f | 257 | |
c97f4736 PZ |
258 | if (!event->parent) { |
259 | /* | |
260 | * If this is a !child event, we must hold ctx::mutex to | |
261 | * stabilize the the event->ctx relation. See | |
262 | * perf_event_ctx_lock(). | |
263 | */ | |
264 | lockdep_assert_held(&ctx->mutex); | |
265 | } | |
0017960f PZ |
266 | |
267 | if (!task) { | |
fae3fde6 | 268 | cpu_function_call(event->cpu, event_function, &efs); |
0017960f PZ |
269 | return; |
270 | } | |
271 | ||
63b6da39 PZ |
272 | if (task == TASK_TOMBSTONE) |
273 | return; | |
274 | ||
a096309b | 275 | again: |
fae3fde6 | 276 | if (!task_function_call(task, event_function, &efs)) |
0017960f PZ |
277 | return; |
278 | ||
279 | raw_spin_lock_irq(&ctx->lock); | |
63b6da39 PZ |
280 | /* |
281 | * Reload the task pointer, it might have been changed by | |
282 | * a concurrent perf_event_context_sched_out(). | |
283 | */ | |
284 | task = ctx->task; | |
a096309b PZ |
285 | if (task == TASK_TOMBSTONE) { |
286 | raw_spin_unlock_irq(&ctx->lock); | |
287 | return; | |
0017960f | 288 | } |
a096309b PZ |
289 | if (ctx->is_active) { |
290 | raw_spin_unlock_irq(&ctx->lock); | |
291 | goto again; | |
292 | } | |
293 | func(event, NULL, ctx, data); | |
0017960f PZ |
294 | raw_spin_unlock_irq(&ctx->lock); |
295 | } | |
296 | ||
cca20946 PZ |
297 | /* |
298 | * Similar to event_function_call() + event_function(), but hard assumes IRQs | |
299 | * are already disabled and we're on the right CPU. | |
300 | */ | |
301 | static void event_function_local(struct perf_event *event, event_f func, void *data) | |
302 | { | |
303 | struct perf_event_context *ctx = event->ctx; | |
304 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
305 | struct task_struct *task = READ_ONCE(ctx->task); | |
306 | struct perf_event_context *task_ctx = NULL; | |
307 | ||
16444645 | 308 | lockdep_assert_irqs_disabled(); |
cca20946 PZ |
309 | |
310 | if (task) { | |
311 | if (task == TASK_TOMBSTONE) | |
312 | return; | |
313 | ||
314 | task_ctx = ctx; | |
315 | } | |
316 | ||
317 | perf_ctx_lock(cpuctx, task_ctx); | |
318 | ||
319 | task = ctx->task; | |
320 | if (task == TASK_TOMBSTONE) | |
321 | goto unlock; | |
322 | ||
323 | if (task) { | |
324 | /* | |
325 | * We must be either inactive or active and the right task, | |
326 | * otherwise we're screwed, since we cannot IPI to somewhere | |
327 | * else. | |
328 | */ | |
329 | if (ctx->is_active) { | |
330 | if (WARN_ON_ONCE(task != current)) | |
331 | goto unlock; | |
332 | ||
333 | if (WARN_ON_ONCE(cpuctx->task_ctx != ctx)) | |
334 | goto unlock; | |
335 | } | |
336 | } else { | |
337 | WARN_ON_ONCE(&cpuctx->ctx != ctx); | |
338 | } | |
339 | ||
340 | func(event, cpuctx, ctx, data); | |
341 | unlock: | |
342 | perf_ctx_unlock(cpuctx, task_ctx); | |
343 | } | |
344 | ||
e5d1367f SE |
345 | #define PERF_FLAG_ALL (PERF_FLAG_FD_NO_GROUP |\ |
346 | PERF_FLAG_FD_OUTPUT |\ | |
a21b0b35 YD |
347 | PERF_FLAG_PID_CGROUP |\ |
348 | PERF_FLAG_FD_CLOEXEC) | |
e5d1367f | 349 | |
bce38cd5 SE |
350 | /* |
351 | * branch priv levels that need permission checks | |
352 | */ | |
353 | #define PERF_SAMPLE_BRANCH_PERM_PLM \ | |
354 | (PERF_SAMPLE_BRANCH_KERNEL |\ | |
355 | PERF_SAMPLE_BRANCH_HV) | |
356 | ||
0b3fcf17 SE |
357 | enum event_type_t { |
358 | EVENT_FLEXIBLE = 0x1, | |
359 | EVENT_PINNED = 0x2, | |
3cbaa590 | 360 | EVENT_TIME = 0x4, |
487f05e1 AS |
361 | /* see ctx_resched() for details */ |
362 | EVENT_CPU = 0x8, | |
0b3fcf17 SE |
363 | EVENT_ALL = EVENT_FLEXIBLE | EVENT_PINNED, |
364 | }; | |
365 | ||
e5d1367f SE |
366 | /* |
367 | * perf_sched_events : >0 events exist | |
368 | * perf_cgroup_events: >0 per-cpu cgroup events exist on this cpu | |
369 | */ | |
9107c89e PZ |
370 | |
371 | static void perf_sched_delayed(struct work_struct *work); | |
372 | DEFINE_STATIC_KEY_FALSE(perf_sched_events); | |
373 | static DECLARE_DELAYED_WORK(perf_sched_work, perf_sched_delayed); | |
374 | static DEFINE_MUTEX(perf_sched_mutex); | |
375 | static atomic_t perf_sched_count; | |
376 | ||
e5d1367f | 377 | static DEFINE_PER_CPU(atomic_t, perf_cgroup_events); |
ba532500 | 378 | static DEFINE_PER_CPU(int, perf_sched_cb_usages); |
f2fb6bef | 379 | static DEFINE_PER_CPU(struct pmu_event_list, pmu_sb_events); |
e5d1367f | 380 | |
cdd6c482 IM |
381 | static atomic_t nr_mmap_events __read_mostly; |
382 | static atomic_t nr_comm_events __read_mostly; | |
e4222673 | 383 | static atomic_t nr_namespaces_events __read_mostly; |
cdd6c482 | 384 | static atomic_t nr_task_events __read_mostly; |
948b26b6 | 385 | static atomic_t nr_freq_events __read_mostly; |
45ac1403 | 386 | static atomic_t nr_switch_events __read_mostly; |
76193a94 | 387 | static atomic_t nr_ksymbol_events __read_mostly; |
6ee52e2a | 388 | static atomic_t nr_bpf_events __read_mostly; |
9ee318a7 | 389 | |
108b02cf PZ |
390 | static LIST_HEAD(pmus); |
391 | static DEFINE_MUTEX(pmus_lock); | |
392 | static struct srcu_struct pmus_srcu; | |
a63fbed7 | 393 | static cpumask_var_t perf_online_mask; |
108b02cf | 394 | |
0764771d | 395 | /* |
cdd6c482 | 396 | * perf event paranoia level: |
0fbdea19 IM |
397 | * -1 - not paranoid at all |
398 | * 0 - disallow raw tracepoint access for unpriv | |
cdd6c482 | 399 | * 1 - disallow cpu events for unpriv |
0fbdea19 | 400 | * 2 - disallow kernel profiling for unpriv |
0764771d | 401 | */ |
0161028b | 402 | int sysctl_perf_event_paranoid __read_mostly = 2; |
0764771d | 403 | |
20443384 FW |
404 | /* Minimum for 512 kiB + 1 user control page */ |
405 | int sysctl_perf_event_mlock __read_mostly = 512 + (PAGE_SIZE / 1024); /* 'free' kiB per user */ | |
df58ab24 PZ |
406 | |
407 | /* | |
cdd6c482 | 408 | * max perf event sample rate |
df58ab24 | 409 | */ |
14c63f17 DH |
410 | #define DEFAULT_MAX_SAMPLE_RATE 100000 |
411 | #define DEFAULT_SAMPLE_PERIOD_NS (NSEC_PER_SEC / DEFAULT_MAX_SAMPLE_RATE) | |
412 | #define DEFAULT_CPU_TIME_MAX_PERCENT 25 | |
413 | ||
414 | int sysctl_perf_event_sample_rate __read_mostly = DEFAULT_MAX_SAMPLE_RATE; | |
415 | ||
416 | static int max_samples_per_tick __read_mostly = DIV_ROUND_UP(DEFAULT_MAX_SAMPLE_RATE, HZ); | |
417 | static int perf_sample_period_ns __read_mostly = DEFAULT_SAMPLE_PERIOD_NS; | |
418 | ||
d9494cb4 PZ |
419 | static int perf_sample_allowed_ns __read_mostly = |
420 | DEFAULT_SAMPLE_PERIOD_NS * DEFAULT_CPU_TIME_MAX_PERCENT / 100; | |
14c63f17 | 421 | |
18ab2cd3 | 422 | static void update_perf_cpu_limits(void) |
14c63f17 DH |
423 | { |
424 | u64 tmp = perf_sample_period_ns; | |
425 | ||
426 | tmp *= sysctl_perf_cpu_time_max_percent; | |
91a612ee PZ |
427 | tmp = div_u64(tmp, 100); |
428 | if (!tmp) | |
429 | tmp = 1; | |
430 | ||
431 | WRITE_ONCE(perf_sample_allowed_ns, tmp); | |
14c63f17 | 432 | } |
163ec435 | 433 | |
8d5bce0c | 434 | static bool perf_rotate_context(struct perf_cpu_context *cpuctx); |
9e630205 | 435 | |
163ec435 PZ |
436 | int perf_proc_update_handler(struct ctl_table *table, int write, |
437 | void __user *buffer, size_t *lenp, | |
438 | loff_t *ppos) | |
439 | { | |
1a51c5da SE |
440 | int ret; |
441 | int perf_cpu = sysctl_perf_cpu_time_max_percent; | |
ab7fdefb KL |
442 | /* |
443 | * If throttling is disabled don't allow the write: | |
444 | */ | |
1a51c5da | 445 | if (write && (perf_cpu == 100 || perf_cpu == 0)) |
ab7fdefb KL |
446 | return -EINVAL; |
447 | ||
1a51c5da SE |
448 | ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
449 | if (ret || !write) | |
450 | return ret; | |
451 | ||
163ec435 | 452 | max_samples_per_tick = DIV_ROUND_UP(sysctl_perf_event_sample_rate, HZ); |
14c63f17 DH |
453 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; |
454 | update_perf_cpu_limits(); | |
455 | ||
456 | return 0; | |
457 | } | |
458 | ||
459 | int sysctl_perf_cpu_time_max_percent __read_mostly = DEFAULT_CPU_TIME_MAX_PERCENT; | |
460 | ||
461 | int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write, | |
462 | void __user *buffer, size_t *lenp, | |
463 | loff_t *ppos) | |
464 | { | |
1572e45a | 465 | int ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); |
14c63f17 DH |
466 | |
467 | if (ret || !write) | |
468 | return ret; | |
469 | ||
b303e7c1 PZ |
470 | if (sysctl_perf_cpu_time_max_percent == 100 || |
471 | sysctl_perf_cpu_time_max_percent == 0) { | |
91a612ee PZ |
472 | printk(KERN_WARNING |
473 | "perf: Dynamic interrupt throttling disabled, can hang your system!\n"); | |
474 | WRITE_ONCE(perf_sample_allowed_ns, 0); | |
475 | } else { | |
476 | update_perf_cpu_limits(); | |
477 | } | |
163ec435 PZ |
478 | |
479 | return 0; | |
480 | } | |
1ccd1549 | 481 | |
14c63f17 DH |
482 | /* |
483 | * perf samples are done in some very critical code paths (NMIs). | |
484 | * If they take too much CPU time, the system can lock up and not | |
485 | * get any real work done. This will drop the sample rate when | |
486 | * we detect that events are taking too long. | |
487 | */ | |
488 | #define NR_ACCUMULATED_SAMPLES 128 | |
d9494cb4 | 489 | static DEFINE_PER_CPU(u64, running_sample_length); |
14c63f17 | 490 | |
91a612ee PZ |
491 | static u64 __report_avg; |
492 | static u64 __report_allowed; | |
493 | ||
6a02ad66 | 494 | static void perf_duration_warn(struct irq_work *w) |
14c63f17 | 495 | { |
0d87d7ec | 496 | printk_ratelimited(KERN_INFO |
91a612ee PZ |
497 | "perf: interrupt took too long (%lld > %lld), lowering " |
498 | "kernel.perf_event_max_sample_rate to %d\n", | |
499 | __report_avg, __report_allowed, | |
500 | sysctl_perf_event_sample_rate); | |
6a02ad66 PZ |
501 | } |
502 | ||
503 | static DEFINE_IRQ_WORK(perf_duration_work, perf_duration_warn); | |
504 | ||
505 | void perf_sample_event_took(u64 sample_len_ns) | |
506 | { | |
91a612ee PZ |
507 | u64 max_len = READ_ONCE(perf_sample_allowed_ns); |
508 | u64 running_len; | |
509 | u64 avg_len; | |
510 | u32 max; | |
14c63f17 | 511 | |
91a612ee | 512 | if (max_len == 0) |
14c63f17 DH |
513 | return; |
514 | ||
91a612ee PZ |
515 | /* Decay the counter by 1 average sample. */ |
516 | running_len = __this_cpu_read(running_sample_length); | |
517 | running_len -= running_len/NR_ACCUMULATED_SAMPLES; | |
518 | running_len += sample_len_ns; | |
519 | __this_cpu_write(running_sample_length, running_len); | |
14c63f17 DH |
520 | |
521 | /* | |
91a612ee PZ |
522 | * Note: this will be biased artifically low until we have |
523 | * seen NR_ACCUMULATED_SAMPLES. Doing it this way keeps us | |
14c63f17 DH |
524 | * from having to maintain a count. |
525 | */ | |
91a612ee PZ |
526 | avg_len = running_len/NR_ACCUMULATED_SAMPLES; |
527 | if (avg_len <= max_len) | |
14c63f17 DH |
528 | return; |
529 | ||
91a612ee PZ |
530 | __report_avg = avg_len; |
531 | __report_allowed = max_len; | |
14c63f17 | 532 | |
91a612ee PZ |
533 | /* |
534 | * Compute a throttle threshold 25% below the current duration. | |
535 | */ | |
536 | avg_len += avg_len / 4; | |
537 | max = (TICK_NSEC / 100) * sysctl_perf_cpu_time_max_percent; | |
538 | if (avg_len < max) | |
539 | max /= (u32)avg_len; | |
540 | else | |
541 | max = 1; | |
14c63f17 | 542 | |
91a612ee PZ |
543 | WRITE_ONCE(perf_sample_allowed_ns, avg_len); |
544 | WRITE_ONCE(max_samples_per_tick, max); | |
545 | ||
546 | sysctl_perf_event_sample_rate = max * HZ; | |
547 | perf_sample_period_ns = NSEC_PER_SEC / sysctl_perf_event_sample_rate; | |
6a02ad66 | 548 | |
cd578abb | 549 | if (!irq_work_queue(&perf_duration_work)) { |
91a612ee | 550 | early_printk("perf: interrupt took too long (%lld > %lld), lowering " |
cd578abb | 551 | "kernel.perf_event_max_sample_rate to %d\n", |
91a612ee | 552 | __report_avg, __report_allowed, |
cd578abb PZ |
553 | sysctl_perf_event_sample_rate); |
554 | } | |
14c63f17 DH |
555 | } |
556 | ||
cdd6c482 | 557 | static atomic64_t perf_event_id; |
a96bbc16 | 558 | |
0b3fcf17 SE |
559 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, |
560 | enum event_type_t event_type); | |
561 | ||
562 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
563 | enum event_type_t event_type, |
564 | struct task_struct *task); | |
565 | ||
566 | static void update_context_time(struct perf_event_context *ctx); | |
567 | static u64 perf_event_time(struct perf_event *event); | |
0b3fcf17 | 568 | |
cdd6c482 | 569 | void __weak perf_event_print_debug(void) { } |
0793a61d | 570 | |
84c79910 | 571 | extern __weak const char *perf_pmu_name(void) |
0793a61d | 572 | { |
84c79910 | 573 | return "pmu"; |
0793a61d TG |
574 | } |
575 | ||
0b3fcf17 SE |
576 | static inline u64 perf_clock(void) |
577 | { | |
578 | return local_clock(); | |
579 | } | |
580 | ||
34f43927 PZ |
581 | static inline u64 perf_event_clock(struct perf_event *event) |
582 | { | |
583 | return event->clock(); | |
584 | } | |
585 | ||
0d3d73aa PZ |
586 | /* |
587 | * State based event timekeeping... | |
588 | * | |
589 | * The basic idea is to use event->state to determine which (if any) time | |
590 | * fields to increment with the current delta. This means we only need to | |
591 | * update timestamps when we change state or when they are explicitly requested | |
592 | * (read). | |
593 | * | |
594 | * Event groups make things a little more complicated, but not terribly so. The | |
595 | * rules for a group are that if the group leader is OFF the entire group is | |
596 | * OFF, irrespecive of what the group member states are. This results in | |
597 | * __perf_effective_state(). | |
598 | * | |
599 | * A futher ramification is that when a group leader flips between OFF and | |
600 | * !OFF, we need to update all group member times. | |
601 | * | |
602 | * | |
603 | * NOTE: perf_event_time() is based on the (cgroup) context time, and thus we | |
604 | * need to make sure the relevant context time is updated before we try and | |
605 | * update our timestamps. | |
606 | */ | |
607 | ||
608 | static __always_inline enum perf_event_state | |
609 | __perf_effective_state(struct perf_event *event) | |
610 | { | |
611 | struct perf_event *leader = event->group_leader; | |
612 | ||
613 | if (leader->state <= PERF_EVENT_STATE_OFF) | |
614 | return leader->state; | |
615 | ||
616 | return event->state; | |
617 | } | |
618 | ||
619 | static __always_inline void | |
620 | __perf_update_times(struct perf_event *event, u64 now, u64 *enabled, u64 *running) | |
621 | { | |
622 | enum perf_event_state state = __perf_effective_state(event); | |
623 | u64 delta = now - event->tstamp; | |
624 | ||
625 | *enabled = event->total_time_enabled; | |
626 | if (state >= PERF_EVENT_STATE_INACTIVE) | |
627 | *enabled += delta; | |
628 | ||
629 | *running = event->total_time_running; | |
630 | if (state >= PERF_EVENT_STATE_ACTIVE) | |
631 | *running += delta; | |
632 | } | |
633 | ||
634 | static void perf_event_update_time(struct perf_event *event) | |
635 | { | |
636 | u64 now = perf_event_time(event); | |
637 | ||
638 | __perf_update_times(event, now, &event->total_time_enabled, | |
639 | &event->total_time_running); | |
640 | event->tstamp = now; | |
641 | } | |
642 | ||
643 | static void perf_event_update_sibling_time(struct perf_event *leader) | |
644 | { | |
645 | struct perf_event *sibling; | |
646 | ||
edb39592 | 647 | for_each_sibling_event(sibling, leader) |
0d3d73aa PZ |
648 | perf_event_update_time(sibling); |
649 | } | |
650 | ||
651 | static void | |
652 | perf_event_set_state(struct perf_event *event, enum perf_event_state state) | |
653 | { | |
654 | if (event->state == state) | |
655 | return; | |
656 | ||
657 | perf_event_update_time(event); | |
658 | /* | |
659 | * If a group leader gets enabled/disabled all its siblings | |
660 | * are affected too. | |
661 | */ | |
662 | if ((event->state < 0) ^ (state < 0)) | |
663 | perf_event_update_sibling_time(event); | |
664 | ||
665 | WRITE_ONCE(event->state, state); | |
666 | } | |
667 | ||
e5d1367f SE |
668 | #ifdef CONFIG_CGROUP_PERF |
669 | ||
e5d1367f SE |
670 | static inline bool |
671 | perf_cgroup_match(struct perf_event *event) | |
672 | { | |
673 | struct perf_event_context *ctx = event->ctx; | |
674 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); | |
675 | ||
ef824fa1 TH |
676 | /* @event doesn't care about cgroup */ |
677 | if (!event->cgrp) | |
678 | return true; | |
679 | ||
680 | /* wants specific cgroup scope but @cpuctx isn't associated with any */ | |
681 | if (!cpuctx->cgrp) | |
682 | return false; | |
683 | ||
684 | /* | |
685 | * Cgroup scoping is recursive. An event enabled for a cgroup is | |
686 | * also enabled for all its descendant cgroups. If @cpuctx's | |
687 | * cgroup is a descendant of @event's (the test covers identity | |
688 | * case), it's a match. | |
689 | */ | |
690 | return cgroup_is_descendant(cpuctx->cgrp->css.cgroup, | |
691 | event->cgrp->css.cgroup); | |
e5d1367f SE |
692 | } |
693 | ||
e5d1367f SE |
694 | static inline void perf_detach_cgroup(struct perf_event *event) |
695 | { | |
4e2ba650 | 696 | css_put(&event->cgrp->css); |
e5d1367f SE |
697 | event->cgrp = NULL; |
698 | } | |
699 | ||
700 | static inline int is_cgroup_event(struct perf_event *event) | |
701 | { | |
702 | return event->cgrp != NULL; | |
703 | } | |
704 | ||
705 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
706 | { | |
707 | struct perf_cgroup_info *t; | |
708 | ||
709 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
710 | return t->time; | |
711 | } | |
712 | ||
713 | static inline void __update_cgrp_time(struct perf_cgroup *cgrp) | |
714 | { | |
715 | struct perf_cgroup_info *info; | |
716 | u64 now; | |
717 | ||
718 | now = perf_clock(); | |
719 | ||
720 | info = this_cpu_ptr(cgrp->info); | |
721 | ||
722 | info->time += now - info->timestamp; | |
723 | info->timestamp = now; | |
724 | } | |
725 | ||
726 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
727 | { | |
c917e0f2 SL |
728 | struct perf_cgroup *cgrp = cpuctx->cgrp; |
729 | struct cgroup_subsys_state *css; | |
730 | ||
731 | if (cgrp) { | |
732 | for (css = &cgrp->css; css; css = css->parent) { | |
733 | cgrp = container_of(css, struct perf_cgroup, css); | |
734 | __update_cgrp_time(cgrp); | |
735 | } | |
736 | } | |
e5d1367f SE |
737 | } |
738 | ||
739 | static inline void update_cgrp_time_from_event(struct perf_event *event) | |
740 | { | |
3f7cce3c SE |
741 | struct perf_cgroup *cgrp; |
742 | ||
e5d1367f | 743 | /* |
3f7cce3c SE |
744 | * ensure we access cgroup data only when needed and |
745 | * when we know the cgroup is pinned (css_get) | |
e5d1367f | 746 | */ |
3f7cce3c | 747 | if (!is_cgroup_event(event)) |
e5d1367f SE |
748 | return; |
749 | ||
614e4c4e | 750 | cgrp = perf_cgroup_from_task(current, event->ctx); |
3f7cce3c SE |
751 | /* |
752 | * Do not update time when cgroup is not active | |
753 | */ | |
28fa741c | 754 | if (cgroup_is_descendant(cgrp->css.cgroup, event->cgrp->css.cgroup)) |
3f7cce3c | 755 | __update_cgrp_time(event->cgrp); |
e5d1367f SE |
756 | } |
757 | ||
758 | static inline void | |
3f7cce3c SE |
759 | perf_cgroup_set_timestamp(struct task_struct *task, |
760 | struct perf_event_context *ctx) | |
e5d1367f SE |
761 | { |
762 | struct perf_cgroup *cgrp; | |
763 | struct perf_cgroup_info *info; | |
c917e0f2 | 764 | struct cgroup_subsys_state *css; |
e5d1367f | 765 | |
3f7cce3c SE |
766 | /* |
767 | * ctx->lock held by caller | |
768 | * ensure we do not access cgroup data | |
769 | * unless we have the cgroup pinned (css_get) | |
770 | */ | |
771 | if (!task || !ctx->nr_cgroups) | |
e5d1367f SE |
772 | return; |
773 | ||
614e4c4e | 774 | cgrp = perf_cgroup_from_task(task, ctx); |
c917e0f2 SL |
775 | |
776 | for (css = &cgrp->css; css; css = css->parent) { | |
777 | cgrp = container_of(css, struct perf_cgroup, css); | |
778 | info = this_cpu_ptr(cgrp->info); | |
779 | info->timestamp = ctx->timestamp; | |
780 | } | |
e5d1367f SE |
781 | } |
782 | ||
058fe1c0 DCC |
783 | static DEFINE_PER_CPU(struct list_head, cgrp_cpuctx_list); |
784 | ||
e5d1367f SE |
785 | #define PERF_CGROUP_SWOUT 0x1 /* cgroup switch out every event */ |
786 | #define PERF_CGROUP_SWIN 0x2 /* cgroup switch in events based on task */ | |
787 | ||
788 | /* | |
789 | * reschedule events based on the cgroup constraint of task. | |
790 | * | |
791 | * mode SWOUT : schedule out everything | |
792 | * mode SWIN : schedule in based on cgroup for next | |
793 | */ | |
18ab2cd3 | 794 | static void perf_cgroup_switch(struct task_struct *task, int mode) |
e5d1367f SE |
795 | { |
796 | struct perf_cpu_context *cpuctx; | |
058fe1c0 | 797 | struct list_head *list; |
e5d1367f SE |
798 | unsigned long flags; |
799 | ||
800 | /* | |
058fe1c0 DCC |
801 | * Disable interrupts and preemption to avoid this CPU's |
802 | * cgrp_cpuctx_entry to change under us. | |
e5d1367f SE |
803 | */ |
804 | local_irq_save(flags); | |
805 | ||
058fe1c0 DCC |
806 | list = this_cpu_ptr(&cgrp_cpuctx_list); |
807 | list_for_each_entry(cpuctx, list, cgrp_cpuctx_entry) { | |
808 | WARN_ON_ONCE(cpuctx->ctx.nr_cgroups == 0); | |
e5d1367f | 809 | |
058fe1c0 DCC |
810 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
811 | perf_pmu_disable(cpuctx->ctx.pmu); | |
e5d1367f | 812 | |
058fe1c0 DCC |
813 | if (mode & PERF_CGROUP_SWOUT) { |
814 | cpu_ctx_sched_out(cpuctx, EVENT_ALL); | |
815 | /* | |
816 | * must not be done before ctxswout due | |
817 | * to event_filter_match() in event_sched_out() | |
818 | */ | |
819 | cpuctx->cgrp = NULL; | |
820 | } | |
e5d1367f | 821 | |
058fe1c0 DCC |
822 | if (mode & PERF_CGROUP_SWIN) { |
823 | WARN_ON_ONCE(cpuctx->cgrp); | |
824 | /* | |
825 | * set cgrp before ctxsw in to allow | |
826 | * event_filter_match() to not have to pass | |
827 | * task around | |
828 | * we pass the cpuctx->ctx to perf_cgroup_from_task() | |
829 | * because cgorup events are only per-cpu | |
830 | */ | |
831 | cpuctx->cgrp = perf_cgroup_from_task(task, | |
832 | &cpuctx->ctx); | |
833 | cpu_ctx_sched_in(cpuctx, EVENT_ALL, task); | |
e5d1367f | 834 | } |
058fe1c0 DCC |
835 | perf_pmu_enable(cpuctx->ctx.pmu); |
836 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
e5d1367f SE |
837 | } |
838 | ||
e5d1367f SE |
839 | local_irq_restore(flags); |
840 | } | |
841 | ||
a8d757ef SE |
842 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
843 | struct task_struct *next) | |
e5d1367f | 844 | { |
a8d757ef SE |
845 | struct perf_cgroup *cgrp1; |
846 | struct perf_cgroup *cgrp2 = NULL; | |
847 | ||
ddaaf4e2 | 848 | rcu_read_lock(); |
a8d757ef SE |
849 | /* |
850 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
851 | * we do not need to pass the ctx here because we know |
852 | * we are holding the rcu lock | |
a8d757ef | 853 | */ |
614e4c4e | 854 | cgrp1 = perf_cgroup_from_task(task, NULL); |
70a01657 | 855 | cgrp2 = perf_cgroup_from_task(next, NULL); |
a8d757ef SE |
856 | |
857 | /* | |
858 | * only schedule out current cgroup events if we know | |
859 | * that we are switching to a different cgroup. Otherwise, | |
860 | * do no touch the cgroup events. | |
861 | */ | |
862 | if (cgrp1 != cgrp2) | |
863 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT); | |
ddaaf4e2 SE |
864 | |
865 | rcu_read_unlock(); | |
e5d1367f SE |
866 | } |
867 | ||
a8d757ef SE |
868 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
869 | struct task_struct *task) | |
e5d1367f | 870 | { |
a8d757ef SE |
871 | struct perf_cgroup *cgrp1; |
872 | struct perf_cgroup *cgrp2 = NULL; | |
873 | ||
ddaaf4e2 | 874 | rcu_read_lock(); |
a8d757ef SE |
875 | /* |
876 | * we come here when we know perf_cgroup_events > 0 | |
614e4c4e SE |
877 | * we do not need to pass the ctx here because we know |
878 | * we are holding the rcu lock | |
a8d757ef | 879 | */ |
614e4c4e | 880 | cgrp1 = perf_cgroup_from_task(task, NULL); |
614e4c4e | 881 | cgrp2 = perf_cgroup_from_task(prev, NULL); |
a8d757ef SE |
882 | |
883 | /* | |
884 | * only need to schedule in cgroup events if we are changing | |
885 | * cgroup during ctxsw. Cgroup events were not scheduled | |
886 | * out of ctxsw out if that was not the case. | |
887 | */ | |
888 | if (cgrp1 != cgrp2) | |
889 | perf_cgroup_switch(task, PERF_CGROUP_SWIN); | |
ddaaf4e2 SE |
890 | |
891 | rcu_read_unlock(); | |
e5d1367f SE |
892 | } |
893 | ||
894 | static inline int perf_cgroup_connect(int fd, struct perf_event *event, | |
895 | struct perf_event_attr *attr, | |
896 | struct perf_event *group_leader) | |
897 | { | |
898 | struct perf_cgroup *cgrp; | |
899 | struct cgroup_subsys_state *css; | |
2903ff01 AV |
900 | struct fd f = fdget(fd); |
901 | int ret = 0; | |
e5d1367f | 902 | |
2903ff01 | 903 | if (!f.file) |
e5d1367f SE |
904 | return -EBADF; |
905 | ||
b583043e | 906 | css = css_tryget_online_from_dir(f.file->f_path.dentry, |
ec903c0c | 907 | &perf_event_cgrp_subsys); |
3db272c0 LZ |
908 | if (IS_ERR(css)) { |
909 | ret = PTR_ERR(css); | |
910 | goto out; | |
911 | } | |
e5d1367f SE |
912 | |
913 | cgrp = container_of(css, struct perf_cgroup, css); | |
914 | event->cgrp = cgrp; | |
915 | ||
916 | /* | |
917 | * all events in a group must monitor | |
918 | * the same cgroup because a task belongs | |
919 | * to only one perf cgroup at a time | |
920 | */ | |
921 | if (group_leader && group_leader->cgrp != cgrp) { | |
922 | perf_detach_cgroup(event); | |
923 | ret = -EINVAL; | |
e5d1367f | 924 | } |
3db272c0 | 925 | out: |
2903ff01 | 926 | fdput(f); |
e5d1367f SE |
927 | return ret; |
928 | } | |
929 | ||
930 | static inline void | |
931 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
932 | { | |
933 | struct perf_cgroup_info *t; | |
934 | t = per_cpu_ptr(event->cgrp->info, event->cpu); | |
935 | event->shadow_ctx_time = now - t->timestamp; | |
936 | } | |
937 | ||
db4a8356 DCC |
938 | /* |
939 | * Update cpuctx->cgrp so that it is set when first cgroup event is added and | |
940 | * cleared when last cgroup event is removed. | |
941 | */ | |
942 | static inline void | |
943 | list_update_cgroup_event(struct perf_event *event, | |
944 | struct perf_event_context *ctx, bool add) | |
945 | { | |
946 | struct perf_cpu_context *cpuctx; | |
058fe1c0 | 947 | struct list_head *cpuctx_entry; |
db4a8356 DCC |
948 | |
949 | if (!is_cgroup_event(event)) | |
950 | return; | |
951 | ||
db4a8356 DCC |
952 | /* |
953 | * Because cgroup events are always per-cpu events, | |
954 | * this will always be called from the right CPU. | |
955 | */ | |
956 | cpuctx = __get_cpu_context(ctx); | |
33801b94 | 957 | |
958 | /* | |
959 | * Since setting cpuctx->cgrp is conditional on the current @cgrp | |
960 | * matching the event's cgroup, we must do this for every new event, | |
961 | * because if the first would mismatch, the second would not try again | |
962 | * and we would leave cpuctx->cgrp unset. | |
963 | */ | |
964 | if (add && !cpuctx->cgrp) { | |
be96b316 TH |
965 | struct perf_cgroup *cgrp = perf_cgroup_from_task(current, ctx); |
966 | ||
be96b316 TH |
967 | if (cgroup_is_descendant(cgrp->css.cgroup, event->cgrp->css.cgroup)) |
968 | cpuctx->cgrp = cgrp; | |
058fe1c0 | 969 | } |
33801b94 | 970 | |
971 | if (add && ctx->nr_cgroups++) | |
972 | return; | |
973 | else if (!add && --ctx->nr_cgroups) | |
974 | return; | |
975 | ||
976 | /* no cgroup running */ | |
977 | if (!add) | |
978 | cpuctx->cgrp = NULL; | |
979 | ||
980 | cpuctx_entry = &cpuctx->cgrp_cpuctx_entry; | |
981 | if (add) | |
982 | list_add(cpuctx_entry, this_cpu_ptr(&cgrp_cpuctx_list)); | |
983 | else | |
984 | list_del(cpuctx_entry); | |
db4a8356 DCC |
985 | } |
986 | ||
e5d1367f SE |
987 | #else /* !CONFIG_CGROUP_PERF */ |
988 | ||
989 | static inline bool | |
990 | perf_cgroup_match(struct perf_event *event) | |
991 | { | |
992 | return true; | |
993 | } | |
994 | ||
995 | static inline void perf_detach_cgroup(struct perf_event *event) | |
996 | {} | |
997 | ||
998 | static inline int is_cgroup_event(struct perf_event *event) | |
999 | { | |
1000 | return 0; | |
1001 | } | |
1002 | ||
e5d1367f SE |
1003 | static inline void update_cgrp_time_from_event(struct perf_event *event) |
1004 | { | |
1005 | } | |
1006 | ||
1007 | static inline void update_cgrp_time_from_cpuctx(struct perf_cpu_context *cpuctx) | |
1008 | { | |
1009 | } | |
1010 | ||
a8d757ef SE |
1011 | static inline void perf_cgroup_sched_out(struct task_struct *task, |
1012 | struct task_struct *next) | |
e5d1367f SE |
1013 | { |
1014 | } | |
1015 | ||
a8d757ef SE |
1016 | static inline void perf_cgroup_sched_in(struct task_struct *prev, |
1017 | struct task_struct *task) | |
e5d1367f SE |
1018 | { |
1019 | } | |
1020 | ||
1021 | static inline int perf_cgroup_connect(pid_t pid, struct perf_event *event, | |
1022 | struct perf_event_attr *attr, | |
1023 | struct perf_event *group_leader) | |
1024 | { | |
1025 | return -EINVAL; | |
1026 | } | |
1027 | ||
1028 | static inline void | |
3f7cce3c SE |
1029 | perf_cgroup_set_timestamp(struct task_struct *task, |
1030 | struct perf_event_context *ctx) | |
e5d1367f SE |
1031 | { |
1032 | } | |
1033 | ||
1034 | void | |
1035 | perf_cgroup_switch(struct task_struct *task, struct task_struct *next) | |
1036 | { | |
1037 | } | |
1038 | ||
1039 | static inline void | |
1040 | perf_cgroup_set_shadow_time(struct perf_event *event, u64 now) | |
1041 | { | |
1042 | } | |
1043 | ||
1044 | static inline u64 perf_cgroup_event_time(struct perf_event *event) | |
1045 | { | |
1046 | return 0; | |
1047 | } | |
1048 | ||
db4a8356 DCC |
1049 | static inline void |
1050 | list_update_cgroup_event(struct perf_event *event, | |
1051 | struct perf_event_context *ctx, bool add) | |
1052 | { | |
1053 | } | |
1054 | ||
e5d1367f SE |
1055 | #endif |
1056 | ||
9e630205 SE |
1057 | /* |
1058 | * set default to be dependent on timer tick just | |
1059 | * like original code | |
1060 | */ | |
1061 | #define PERF_CPU_HRTIMER (1000 / HZ) | |
1062 | /* | |
8a1115ff | 1063 | * function must be called with interrupts disabled |
9e630205 | 1064 | */ |
272325c4 | 1065 | static enum hrtimer_restart perf_mux_hrtimer_handler(struct hrtimer *hr) |
9e630205 SE |
1066 | { |
1067 | struct perf_cpu_context *cpuctx; | |
8d5bce0c | 1068 | bool rotations; |
9e630205 | 1069 | |
16444645 | 1070 | lockdep_assert_irqs_disabled(); |
9e630205 SE |
1071 | |
1072 | cpuctx = container_of(hr, struct perf_cpu_context, hrtimer); | |
9e630205 SE |
1073 | rotations = perf_rotate_context(cpuctx); |
1074 | ||
4cfafd30 PZ |
1075 | raw_spin_lock(&cpuctx->hrtimer_lock); |
1076 | if (rotations) | |
9e630205 | 1077 | hrtimer_forward_now(hr, cpuctx->hrtimer_interval); |
4cfafd30 PZ |
1078 | else |
1079 | cpuctx->hrtimer_active = 0; | |
1080 | raw_spin_unlock(&cpuctx->hrtimer_lock); | |
9e630205 | 1081 | |
4cfafd30 | 1082 | return rotations ? HRTIMER_RESTART : HRTIMER_NORESTART; |
9e630205 SE |
1083 | } |
1084 | ||
272325c4 | 1085 | static void __perf_mux_hrtimer_init(struct perf_cpu_context *cpuctx, int cpu) |
9e630205 | 1086 | { |
272325c4 | 1087 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1088 | struct pmu *pmu = cpuctx->ctx.pmu; |
272325c4 | 1089 | u64 interval; |
9e630205 SE |
1090 | |
1091 | /* no multiplexing needed for SW PMU */ | |
1092 | if (pmu->task_ctx_nr == perf_sw_context) | |
1093 | return; | |
1094 | ||
62b85639 SE |
1095 | /* |
1096 | * check default is sane, if not set then force to | |
1097 | * default interval (1/tick) | |
1098 | */ | |
272325c4 PZ |
1099 | interval = pmu->hrtimer_interval_ms; |
1100 | if (interval < 1) | |
1101 | interval = pmu->hrtimer_interval_ms = PERF_CPU_HRTIMER; | |
62b85639 | 1102 | |
272325c4 | 1103 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * interval); |
9e630205 | 1104 | |
4cfafd30 PZ |
1105 | raw_spin_lock_init(&cpuctx->hrtimer_lock); |
1106 | hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_PINNED); | |
272325c4 | 1107 | timer->function = perf_mux_hrtimer_handler; |
9e630205 SE |
1108 | } |
1109 | ||
272325c4 | 1110 | static int perf_mux_hrtimer_restart(struct perf_cpu_context *cpuctx) |
9e630205 | 1111 | { |
272325c4 | 1112 | struct hrtimer *timer = &cpuctx->hrtimer; |
9e630205 | 1113 | struct pmu *pmu = cpuctx->ctx.pmu; |
4cfafd30 | 1114 | unsigned long flags; |
9e630205 SE |
1115 | |
1116 | /* not for SW PMU */ | |
1117 | if (pmu->task_ctx_nr == perf_sw_context) | |
272325c4 | 1118 | return 0; |
9e630205 | 1119 | |
4cfafd30 PZ |
1120 | raw_spin_lock_irqsave(&cpuctx->hrtimer_lock, flags); |
1121 | if (!cpuctx->hrtimer_active) { | |
1122 | cpuctx->hrtimer_active = 1; | |
1123 | hrtimer_forward_now(timer, cpuctx->hrtimer_interval); | |
1124 | hrtimer_start_expires(timer, HRTIMER_MODE_ABS_PINNED); | |
1125 | } | |
1126 | raw_spin_unlock_irqrestore(&cpuctx->hrtimer_lock, flags); | |
9e630205 | 1127 | |
272325c4 | 1128 | return 0; |
9e630205 SE |
1129 | } |
1130 | ||
33696fc0 | 1131 | void perf_pmu_disable(struct pmu *pmu) |
9e35ad38 | 1132 | { |
33696fc0 PZ |
1133 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1134 | if (!(*count)++) | |
1135 | pmu->pmu_disable(pmu); | |
9e35ad38 | 1136 | } |
9e35ad38 | 1137 | |
33696fc0 | 1138 | void perf_pmu_enable(struct pmu *pmu) |
9e35ad38 | 1139 | { |
33696fc0 PZ |
1140 | int *count = this_cpu_ptr(pmu->pmu_disable_count); |
1141 | if (!--(*count)) | |
1142 | pmu->pmu_enable(pmu); | |
9e35ad38 | 1143 | } |
9e35ad38 | 1144 | |
2fde4f94 | 1145 | static DEFINE_PER_CPU(struct list_head, active_ctx_list); |
e9d2b064 PZ |
1146 | |
1147 | /* | |
2fde4f94 MR |
1148 | * perf_event_ctx_activate(), perf_event_ctx_deactivate(), and |
1149 | * perf_event_task_tick() are fully serialized because they're strictly cpu | |
1150 | * affine and perf_event_ctx{activate,deactivate} are called with IRQs | |
1151 | * disabled, while perf_event_task_tick is called from IRQ context. | |
e9d2b064 | 1152 | */ |
2fde4f94 | 1153 | static void perf_event_ctx_activate(struct perf_event_context *ctx) |
9e35ad38 | 1154 | { |
2fde4f94 | 1155 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
b5ab4cd5 | 1156 | |
16444645 | 1157 | lockdep_assert_irqs_disabled(); |
b5ab4cd5 | 1158 | |
2fde4f94 MR |
1159 | WARN_ON(!list_empty(&ctx->active_ctx_list)); |
1160 | ||
1161 | list_add(&ctx->active_ctx_list, head); | |
1162 | } | |
1163 | ||
1164 | static void perf_event_ctx_deactivate(struct perf_event_context *ctx) | |
1165 | { | |
16444645 | 1166 | lockdep_assert_irqs_disabled(); |
2fde4f94 MR |
1167 | |
1168 | WARN_ON(list_empty(&ctx->active_ctx_list)); | |
1169 | ||
1170 | list_del_init(&ctx->active_ctx_list); | |
9e35ad38 | 1171 | } |
9e35ad38 | 1172 | |
cdd6c482 | 1173 | static void get_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1174 | { |
8c94abbb | 1175 | refcount_inc(&ctx->refcount); |
a63eaf34 PM |
1176 | } |
1177 | ||
4af57ef2 YZ |
1178 | static void free_ctx(struct rcu_head *head) |
1179 | { | |
1180 | struct perf_event_context *ctx; | |
1181 | ||
1182 | ctx = container_of(head, struct perf_event_context, rcu_head); | |
1183 | kfree(ctx->task_ctx_data); | |
1184 | kfree(ctx); | |
1185 | } | |
1186 | ||
cdd6c482 | 1187 | static void put_ctx(struct perf_event_context *ctx) |
a63eaf34 | 1188 | { |
8c94abbb | 1189 | if (refcount_dec_and_test(&ctx->refcount)) { |
564c2b21 PM |
1190 | if (ctx->parent_ctx) |
1191 | put_ctx(ctx->parent_ctx); | |
63b6da39 | 1192 | if (ctx->task && ctx->task != TASK_TOMBSTONE) |
c93f7669 | 1193 | put_task_struct(ctx->task); |
4af57ef2 | 1194 | call_rcu(&ctx->rcu_head, free_ctx); |
564c2b21 | 1195 | } |
a63eaf34 PM |
1196 | } |
1197 | ||
f63a8daa PZ |
1198 | /* |
1199 | * Because of perf_event::ctx migration in sys_perf_event_open::move_group and | |
1200 | * perf_pmu_migrate_context() we need some magic. | |
1201 | * | |
1202 | * Those places that change perf_event::ctx will hold both | |
1203 | * perf_event_ctx::mutex of the 'old' and 'new' ctx value. | |
1204 | * | |
8b10c5e2 PZ |
1205 | * Lock ordering is by mutex address. There are two other sites where |
1206 | * perf_event_context::mutex nests and those are: | |
1207 | * | |
1208 | * - perf_event_exit_task_context() [ child , 0 ] | |
8ba289b8 PZ |
1209 | * perf_event_exit_event() |
1210 | * put_event() [ parent, 1 ] | |
8b10c5e2 PZ |
1211 | * |
1212 | * - perf_event_init_context() [ parent, 0 ] | |
1213 | * inherit_task_group() | |
1214 | * inherit_group() | |
1215 | * inherit_event() | |
1216 | * perf_event_alloc() | |
1217 | * perf_init_event() | |
1218 | * perf_try_init_event() [ child , 1 ] | |
1219 | * | |
1220 | * While it appears there is an obvious deadlock here -- the parent and child | |
1221 | * nesting levels are inverted between the two. This is in fact safe because | |
1222 | * life-time rules separate them. That is an exiting task cannot fork, and a | |
1223 | * spawning task cannot (yet) exit. | |
1224 | * | |
1225 | * But remember that that these are parent<->child context relations, and | |
1226 | * migration does not affect children, therefore these two orderings should not | |
1227 | * interact. | |
f63a8daa PZ |
1228 | * |
1229 | * The change in perf_event::ctx does not affect children (as claimed above) | |
1230 | * because the sys_perf_event_open() case will install a new event and break | |
1231 | * the ctx parent<->child relation, and perf_pmu_migrate_context() is only | |
1232 | * concerned with cpuctx and that doesn't have children. | |
1233 | * | |
1234 | * The places that change perf_event::ctx will issue: | |
1235 | * | |
1236 | * perf_remove_from_context(); | |
1237 | * synchronize_rcu(); | |
1238 | * perf_install_in_context(); | |
1239 | * | |
1240 | * to affect the change. The remove_from_context() + synchronize_rcu() should | |
1241 | * quiesce the event, after which we can install it in the new location. This | |
1242 | * means that only external vectors (perf_fops, prctl) can perturb the event | |
1243 | * while in transit. Therefore all such accessors should also acquire | |
1244 | * perf_event_context::mutex to serialize against this. | |
1245 | * | |
1246 | * However; because event->ctx can change while we're waiting to acquire | |
1247 | * ctx->mutex we must be careful and use the below perf_event_ctx_lock() | |
1248 | * function. | |
1249 | * | |
1250 | * Lock order: | |
79c9ce57 | 1251 | * cred_guard_mutex |
f63a8daa PZ |
1252 | * task_struct::perf_event_mutex |
1253 | * perf_event_context::mutex | |
f63a8daa | 1254 | * perf_event::child_mutex; |
07c4a776 | 1255 | * perf_event_context::lock |
f63a8daa PZ |
1256 | * perf_event::mmap_mutex |
1257 | * mmap_sem | |
18736eef | 1258 | * perf_addr_filters_head::lock |
82d94856 PZ |
1259 | * |
1260 | * cpu_hotplug_lock | |
1261 | * pmus_lock | |
1262 | * cpuctx->mutex / perf_event_context::mutex | |
f63a8daa | 1263 | */ |
a83fe28e PZ |
1264 | static struct perf_event_context * |
1265 | perf_event_ctx_lock_nested(struct perf_event *event, int nesting) | |
f63a8daa PZ |
1266 | { |
1267 | struct perf_event_context *ctx; | |
1268 | ||
1269 | again: | |
1270 | rcu_read_lock(); | |
6aa7de05 | 1271 | ctx = READ_ONCE(event->ctx); |
8c94abbb | 1272 | if (!refcount_inc_not_zero(&ctx->refcount)) { |
f63a8daa PZ |
1273 | rcu_read_unlock(); |
1274 | goto again; | |
1275 | } | |
1276 | rcu_read_unlock(); | |
1277 | ||
a83fe28e | 1278 | mutex_lock_nested(&ctx->mutex, nesting); |
f63a8daa PZ |
1279 | if (event->ctx != ctx) { |
1280 | mutex_unlock(&ctx->mutex); | |
1281 | put_ctx(ctx); | |
1282 | goto again; | |
1283 | } | |
1284 | ||
1285 | return ctx; | |
1286 | } | |
1287 | ||
a83fe28e PZ |
1288 | static inline struct perf_event_context * |
1289 | perf_event_ctx_lock(struct perf_event *event) | |
1290 | { | |
1291 | return perf_event_ctx_lock_nested(event, 0); | |
1292 | } | |
1293 | ||
f63a8daa PZ |
1294 | static void perf_event_ctx_unlock(struct perf_event *event, |
1295 | struct perf_event_context *ctx) | |
1296 | { | |
1297 | mutex_unlock(&ctx->mutex); | |
1298 | put_ctx(ctx); | |
1299 | } | |
1300 | ||
211de6eb PZ |
1301 | /* |
1302 | * This must be done under the ctx->lock, such as to serialize against | |
1303 | * context_equiv(), therefore we cannot call put_ctx() since that might end up | |
1304 | * calling scheduler related locks and ctx->lock nests inside those. | |
1305 | */ | |
1306 | static __must_check struct perf_event_context * | |
1307 | unclone_ctx(struct perf_event_context *ctx) | |
71a851b4 | 1308 | { |
211de6eb PZ |
1309 | struct perf_event_context *parent_ctx = ctx->parent_ctx; |
1310 | ||
1311 | lockdep_assert_held(&ctx->lock); | |
1312 | ||
1313 | if (parent_ctx) | |
71a851b4 | 1314 | ctx->parent_ctx = NULL; |
5a3126d4 | 1315 | ctx->generation++; |
211de6eb PZ |
1316 | |
1317 | return parent_ctx; | |
71a851b4 PZ |
1318 | } |
1319 | ||
1d953111 ON |
1320 | static u32 perf_event_pid_type(struct perf_event *event, struct task_struct *p, |
1321 | enum pid_type type) | |
6844c09d | 1322 | { |
1d953111 | 1323 | u32 nr; |
6844c09d ACM |
1324 | /* |
1325 | * only top level events have the pid namespace they were created in | |
1326 | */ | |
1327 | if (event->parent) | |
1328 | event = event->parent; | |
1329 | ||
1d953111 ON |
1330 | nr = __task_pid_nr_ns(p, type, event->ns); |
1331 | /* avoid -1 if it is idle thread or runs in another ns */ | |
1332 | if (!nr && !pid_alive(p)) | |
1333 | nr = -1; | |
1334 | return nr; | |
6844c09d ACM |
1335 | } |
1336 | ||
1d953111 | 1337 | static u32 perf_event_pid(struct perf_event *event, struct task_struct *p) |
6844c09d | 1338 | { |
6883f81a | 1339 | return perf_event_pid_type(event, p, PIDTYPE_TGID); |
1d953111 | 1340 | } |
6844c09d | 1341 | |
1d953111 ON |
1342 | static u32 perf_event_tid(struct perf_event *event, struct task_struct *p) |
1343 | { | |
1344 | return perf_event_pid_type(event, p, PIDTYPE_PID); | |
6844c09d ACM |
1345 | } |
1346 | ||
7f453c24 | 1347 | /* |
cdd6c482 | 1348 | * If we inherit events we want to return the parent event id |
7f453c24 PZ |
1349 | * to userspace. |
1350 | */ | |
cdd6c482 | 1351 | static u64 primary_event_id(struct perf_event *event) |
7f453c24 | 1352 | { |
cdd6c482 | 1353 | u64 id = event->id; |
7f453c24 | 1354 | |
cdd6c482 IM |
1355 | if (event->parent) |
1356 | id = event->parent->id; | |
7f453c24 PZ |
1357 | |
1358 | return id; | |
1359 | } | |
1360 | ||
25346b93 | 1361 | /* |
cdd6c482 | 1362 | * Get the perf_event_context for a task and lock it. |
63b6da39 | 1363 | * |
25346b93 PM |
1364 | * This has to cope with with the fact that until it is locked, |
1365 | * the context could get moved to another task. | |
1366 | */ | |
cdd6c482 | 1367 | static struct perf_event_context * |
8dc85d54 | 1368 | perf_lock_task_context(struct task_struct *task, int ctxn, unsigned long *flags) |
25346b93 | 1369 | { |
cdd6c482 | 1370 | struct perf_event_context *ctx; |
25346b93 | 1371 | |
9ed6060d | 1372 | retry: |
058ebd0e PZ |
1373 | /* |
1374 | * One of the few rules of preemptible RCU is that one cannot do | |
1375 | * rcu_read_unlock() while holding a scheduler (or nested) lock when | |
2fd59077 | 1376 | * part of the read side critical section was irqs-enabled -- see |
058ebd0e PZ |
1377 | * rcu_read_unlock_special(). |
1378 | * | |
1379 | * Since ctx->lock nests under rq->lock we must ensure the entire read | |
2fd59077 | 1380 | * side critical section has interrupts disabled. |
058ebd0e | 1381 | */ |
2fd59077 | 1382 | local_irq_save(*flags); |
058ebd0e | 1383 | rcu_read_lock(); |
8dc85d54 | 1384 | ctx = rcu_dereference(task->perf_event_ctxp[ctxn]); |
25346b93 PM |
1385 | if (ctx) { |
1386 | /* | |
1387 | * If this context is a clone of another, it might | |
1388 | * get swapped for another underneath us by | |
cdd6c482 | 1389 | * perf_event_task_sched_out, though the |
25346b93 PM |
1390 | * rcu_read_lock() protects us from any context |
1391 | * getting freed. Lock the context and check if it | |
1392 | * got swapped before we could get the lock, and retry | |
1393 | * if so. If we locked the right context, then it | |
1394 | * can't get swapped on us any more. | |
1395 | */ | |
2fd59077 | 1396 | raw_spin_lock(&ctx->lock); |
8dc85d54 | 1397 | if (ctx != rcu_dereference(task->perf_event_ctxp[ctxn])) { |
2fd59077 | 1398 | raw_spin_unlock(&ctx->lock); |
058ebd0e | 1399 | rcu_read_unlock(); |
2fd59077 | 1400 | local_irq_restore(*flags); |
25346b93 PM |
1401 | goto retry; |
1402 | } | |
b49a9e7e | 1403 | |
63b6da39 | 1404 | if (ctx->task == TASK_TOMBSTONE || |
8c94abbb | 1405 | !refcount_inc_not_zero(&ctx->refcount)) { |
2fd59077 | 1406 | raw_spin_unlock(&ctx->lock); |
b49a9e7e | 1407 | ctx = NULL; |
828b6f0e PZ |
1408 | } else { |
1409 | WARN_ON_ONCE(ctx->task != task); | |
b49a9e7e | 1410 | } |
25346b93 PM |
1411 | } |
1412 | rcu_read_unlock(); | |
2fd59077 PM |
1413 | if (!ctx) |
1414 | local_irq_restore(*flags); | |
25346b93 PM |
1415 | return ctx; |
1416 | } | |
1417 | ||
1418 | /* | |
1419 | * Get the context for a task and increment its pin_count so it | |
1420 | * can't get swapped to another task. This also increments its | |
1421 | * reference count so that the context can't get freed. | |
1422 | */ | |
8dc85d54 PZ |
1423 | static struct perf_event_context * |
1424 | perf_pin_task_context(struct task_struct *task, int ctxn) | |
25346b93 | 1425 | { |
cdd6c482 | 1426 | struct perf_event_context *ctx; |
25346b93 PM |
1427 | unsigned long flags; |
1428 | ||
8dc85d54 | 1429 | ctx = perf_lock_task_context(task, ctxn, &flags); |
25346b93 PM |
1430 | if (ctx) { |
1431 | ++ctx->pin_count; | |
e625cce1 | 1432 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1433 | } |
1434 | return ctx; | |
1435 | } | |
1436 | ||
cdd6c482 | 1437 | static void perf_unpin_context(struct perf_event_context *ctx) |
25346b93 PM |
1438 | { |
1439 | unsigned long flags; | |
1440 | ||
e625cce1 | 1441 | raw_spin_lock_irqsave(&ctx->lock, flags); |
25346b93 | 1442 | --ctx->pin_count; |
e625cce1 | 1443 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
25346b93 PM |
1444 | } |
1445 | ||
f67218c3 PZ |
1446 | /* |
1447 | * Update the record of the current time in a context. | |
1448 | */ | |
1449 | static void update_context_time(struct perf_event_context *ctx) | |
1450 | { | |
1451 | u64 now = perf_clock(); | |
1452 | ||
1453 | ctx->time += now - ctx->timestamp; | |
1454 | ctx->timestamp = now; | |
1455 | } | |
1456 | ||
4158755d SE |
1457 | static u64 perf_event_time(struct perf_event *event) |
1458 | { | |
1459 | struct perf_event_context *ctx = event->ctx; | |
e5d1367f SE |
1460 | |
1461 | if (is_cgroup_event(event)) | |
1462 | return perf_cgroup_event_time(event); | |
1463 | ||
4158755d SE |
1464 | return ctx ? ctx->time : 0; |
1465 | } | |
1466 | ||
487f05e1 AS |
1467 | static enum event_type_t get_event_type(struct perf_event *event) |
1468 | { | |
1469 | struct perf_event_context *ctx = event->ctx; | |
1470 | enum event_type_t event_type; | |
1471 | ||
1472 | lockdep_assert_held(&ctx->lock); | |
1473 | ||
3bda69c1 AS |
1474 | /* |
1475 | * It's 'group type', really, because if our group leader is | |
1476 | * pinned, so are we. | |
1477 | */ | |
1478 | if (event->group_leader != event) | |
1479 | event = event->group_leader; | |
1480 | ||
487f05e1 AS |
1481 | event_type = event->attr.pinned ? EVENT_PINNED : EVENT_FLEXIBLE; |
1482 | if (!ctx->task) | |
1483 | event_type |= EVENT_CPU; | |
1484 | ||
1485 | return event_type; | |
1486 | } | |
1487 | ||
8e1a2031 | 1488 | /* |
161c85fa | 1489 | * Helper function to initialize event group nodes. |
8e1a2031 | 1490 | */ |
161c85fa | 1491 | static void init_event_group(struct perf_event *event) |
8e1a2031 AB |
1492 | { |
1493 | RB_CLEAR_NODE(&event->group_node); | |
1494 | event->group_index = 0; | |
1495 | } | |
1496 | ||
1497 | /* | |
1498 | * Extract pinned or flexible groups from the context | |
161c85fa | 1499 | * based on event attrs bits. |
8e1a2031 AB |
1500 | */ |
1501 | static struct perf_event_groups * | |
1502 | get_event_groups(struct perf_event *event, struct perf_event_context *ctx) | |
889ff015 FW |
1503 | { |
1504 | if (event->attr.pinned) | |
1505 | return &ctx->pinned_groups; | |
1506 | else | |
1507 | return &ctx->flexible_groups; | |
1508 | } | |
1509 | ||
8e1a2031 | 1510 | /* |
161c85fa | 1511 | * Helper function to initializes perf_event_group trees. |
8e1a2031 | 1512 | */ |
161c85fa | 1513 | static void perf_event_groups_init(struct perf_event_groups *groups) |
8e1a2031 AB |
1514 | { |
1515 | groups->tree = RB_ROOT; | |
1516 | groups->index = 0; | |
1517 | } | |
1518 | ||
1519 | /* | |
1520 | * Compare function for event groups; | |
161c85fa PZ |
1521 | * |
1522 | * Implements complex key that first sorts by CPU and then by virtual index | |
1523 | * which provides ordering when rotating groups for the same CPU. | |
8e1a2031 | 1524 | */ |
161c85fa PZ |
1525 | static bool |
1526 | perf_event_groups_less(struct perf_event *left, struct perf_event *right) | |
8e1a2031 | 1527 | { |
161c85fa PZ |
1528 | if (left->cpu < right->cpu) |
1529 | return true; | |
1530 | if (left->cpu > right->cpu) | |
1531 | return false; | |
1532 | ||
1533 | if (left->group_index < right->group_index) | |
1534 | return true; | |
1535 | if (left->group_index > right->group_index) | |
1536 | return false; | |
1537 | ||
1538 | return false; | |
8e1a2031 AB |
1539 | } |
1540 | ||
1541 | /* | |
161c85fa PZ |
1542 | * Insert @event into @groups' tree; using {@event->cpu, ++@groups->index} for |
1543 | * key (see perf_event_groups_less). This places it last inside the CPU | |
1544 | * subtree. | |
8e1a2031 AB |
1545 | */ |
1546 | static void | |
1547 | perf_event_groups_insert(struct perf_event_groups *groups, | |
161c85fa | 1548 | struct perf_event *event) |
8e1a2031 AB |
1549 | { |
1550 | struct perf_event *node_event; | |
1551 | struct rb_node *parent; | |
1552 | struct rb_node **node; | |
1553 | ||
1554 | event->group_index = ++groups->index; | |
1555 | ||
1556 | node = &groups->tree.rb_node; | |
1557 | parent = *node; | |
1558 | ||
1559 | while (*node) { | |
1560 | parent = *node; | |
161c85fa | 1561 | node_event = container_of(*node, struct perf_event, group_node); |
8e1a2031 AB |
1562 | |
1563 | if (perf_event_groups_less(event, node_event)) | |
1564 | node = &parent->rb_left; | |
1565 | else | |
1566 | node = &parent->rb_right; | |
1567 | } | |
1568 | ||
1569 | rb_link_node(&event->group_node, parent, node); | |
1570 | rb_insert_color(&event->group_node, &groups->tree); | |
1571 | } | |
1572 | ||
1573 | /* | |
161c85fa | 1574 | * Helper function to insert event into the pinned or flexible groups. |
8e1a2031 AB |
1575 | */ |
1576 | static void | |
1577 | add_event_to_groups(struct perf_event *event, struct perf_event_context *ctx) | |
1578 | { | |
1579 | struct perf_event_groups *groups; | |
1580 | ||
1581 | groups = get_event_groups(event, ctx); | |
1582 | perf_event_groups_insert(groups, event); | |
1583 | } | |
1584 | ||
1585 | /* | |
161c85fa | 1586 | * Delete a group from a tree. |
8e1a2031 AB |
1587 | */ |
1588 | static void | |
1589 | perf_event_groups_delete(struct perf_event_groups *groups, | |
161c85fa | 1590 | struct perf_event *event) |
8e1a2031 | 1591 | { |
161c85fa PZ |
1592 | WARN_ON_ONCE(RB_EMPTY_NODE(&event->group_node) || |
1593 | RB_EMPTY_ROOT(&groups->tree)); | |
8e1a2031 | 1594 | |
161c85fa | 1595 | rb_erase(&event->group_node, &groups->tree); |
8e1a2031 AB |
1596 | init_event_group(event); |
1597 | } | |
1598 | ||
1599 | /* | |
161c85fa | 1600 | * Helper function to delete event from its groups. |
8e1a2031 AB |
1601 | */ |
1602 | static void | |
1603 | del_event_from_groups(struct perf_event *event, struct perf_event_context *ctx) | |
1604 | { | |
1605 | struct perf_event_groups *groups; | |
1606 | ||
1607 | groups = get_event_groups(event, ctx); | |
1608 | perf_event_groups_delete(groups, event); | |
1609 | } | |
1610 | ||
1611 | /* | |
161c85fa | 1612 | * Get the leftmost event in the @cpu subtree. |
8e1a2031 AB |
1613 | */ |
1614 | static struct perf_event * | |
1615 | perf_event_groups_first(struct perf_event_groups *groups, int cpu) | |
1616 | { | |
1617 | struct perf_event *node_event = NULL, *match = NULL; | |
1618 | struct rb_node *node = groups->tree.rb_node; | |
1619 | ||
1620 | while (node) { | |
161c85fa | 1621 | node_event = container_of(node, struct perf_event, group_node); |
8e1a2031 AB |
1622 | |
1623 | if (cpu < node_event->cpu) { | |
1624 | node = node->rb_left; | |
1625 | } else if (cpu > node_event->cpu) { | |
1626 | node = node->rb_right; | |
1627 | } else { | |
1628 | match = node_event; | |
1629 | node = node->rb_left; | |
1630 | } | |
1631 | } | |
1632 | ||
1633 | return match; | |
1634 | } | |
1635 | ||
1cac7b1a PZ |
1636 | /* |
1637 | * Like rb_entry_next_safe() for the @cpu subtree. | |
1638 | */ | |
1639 | static struct perf_event * | |
1640 | perf_event_groups_next(struct perf_event *event) | |
1641 | { | |
1642 | struct perf_event *next; | |
1643 | ||
1644 | next = rb_entry_safe(rb_next(&event->group_node), typeof(*event), group_node); | |
1645 | if (next && next->cpu == event->cpu) | |
1646 | return next; | |
1647 | ||
1648 | return NULL; | |
1649 | } | |
1650 | ||
8e1a2031 | 1651 | /* |
161c85fa | 1652 | * Iterate through the whole groups tree. |
8e1a2031 | 1653 | */ |
6e6804d2 PZ |
1654 | #define perf_event_groups_for_each(event, groups) \ |
1655 | for (event = rb_entry_safe(rb_first(&((groups)->tree)), \ | |
1656 | typeof(*event), group_node); event; \ | |
1657 | event = rb_entry_safe(rb_next(&event->group_node), \ | |
1658 | typeof(*event), group_node)) | |
8e1a2031 | 1659 | |
fccc714b | 1660 | /* |
788faab7 | 1661 | * Add an event from the lists for its context. |
fccc714b PZ |
1662 | * Must be called with ctx->mutex and ctx->lock held. |
1663 | */ | |
04289bb9 | 1664 | static void |
cdd6c482 | 1665 | list_add_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1666 | { |
c994d613 PZ |
1667 | lockdep_assert_held(&ctx->lock); |
1668 | ||
8a49542c PZ |
1669 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); |
1670 | event->attach_state |= PERF_ATTACH_CONTEXT; | |
04289bb9 | 1671 | |
0d3d73aa PZ |
1672 | event->tstamp = perf_event_time(event); |
1673 | ||
04289bb9 | 1674 | /* |
8a49542c PZ |
1675 | * If we're a stand alone event or group leader, we go to the context |
1676 | * list, group events are kept attached to the group so that | |
1677 | * perf_group_detach can, at all times, locate all siblings. | |
04289bb9 | 1678 | */ |
8a49542c | 1679 | if (event->group_leader == event) { |
4ff6a8de | 1680 | event->group_caps = event->event_caps; |
8e1a2031 | 1681 | add_event_to_groups(event, ctx); |
5c148194 | 1682 | } |
592903cd | 1683 | |
db4a8356 | 1684 | list_update_cgroup_event(event, ctx, true); |
e5d1367f | 1685 | |
cdd6c482 IM |
1686 | list_add_rcu(&event->event_entry, &ctx->event_list); |
1687 | ctx->nr_events++; | |
1688 | if (event->attr.inherit_stat) | |
bfbd3381 | 1689 | ctx->nr_stat++; |
5a3126d4 PZ |
1690 | |
1691 | ctx->generation++; | |
04289bb9 IM |
1692 | } |
1693 | ||
0231bb53 JO |
1694 | /* |
1695 | * Initialize event state based on the perf_event_attr::disabled. | |
1696 | */ | |
1697 | static inline void perf_event__state_init(struct perf_event *event) | |
1698 | { | |
1699 | event->state = event->attr.disabled ? PERF_EVENT_STATE_OFF : | |
1700 | PERF_EVENT_STATE_INACTIVE; | |
1701 | } | |
1702 | ||
a723968c | 1703 | static void __perf_event_read_size(struct perf_event *event, int nr_siblings) |
c320c7b7 ACM |
1704 | { |
1705 | int entry = sizeof(u64); /* value */ | |
1706 | int size = 0; | |
1707 | int nr = 1; | |
1708 | ||
1709 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
1710 | size += sizeof(u64); | |
1711 | ||
1712 | if (event->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
1713 | size += sizeof(u64); | |
1714 | ||
1715 | if (event->attr.read_format & PERF_FORMAT_ID) | |
1716 | entry += sizeof(u64); | |
1717 | ||
1718 | if (event->attr.read_format & PERF_FORMAT_GROUP) { | |
a723968c | 1719 | nr += nr_siblings; |
c320c7b7 ACM |
1720 | size += sizeof(u64); |
1721 | } | |
1722 | ||
1723 | size += entry * nr; | |
1724 | event->read_size = size; | |
1725 | } | |
1726 | ||
a723968c | 1727 | static void __perf_event_header_size(struct perf_event *event, u64 sample_type) |
c320c7b7 ACM |
1728 | { |
1729 | struct perf_sample_data *data; | |
c320c7b7 ACM |
1730 | u16 size = 0; |
1731 | ||
c320c7b7 ACM |
1732 | if (sample_type & PERF_SAMPLE_IP) |
1733 | size += sizeof(data->ip); | |
1734 | ||
6844c09d ACM |
1735 | if (sample_type & PERF_SAMPLE_ADDR) |
1736 | size += sizeof(data->addr); | |
1737 | ||
1738 | if (sample_type & PERF_SAMPLE_PERIOD) | |
1739 | size += sizeof(data->period); | |
1740 | ||
c3feedf2 AK |
1741 | if (sample_type & PERF_SAMPLE_WEIGHT) |
1742 | size += sizeof(data->weight); | |
1743 | ||
6844c09d ACM |
1744 | if (sample_type & PERF_SAMPLE_READ) |
1745 | size += event->read_size; | |
1746 | ||
d6be9ad6 SE |
1747 | if (sample_type & PERF_SAMPLE_DATA_SRC) |
1748 | size += sizeof(data->data_src.val); | |
1749 | ||
fdfbbd07 AK |
1750 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
1751 | size += sizeof(data->txn); | |
1752 | ||
fc7ce9c7 KL |
1753 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) |
1754 | size += sizeof(data->phys_addr); | |
1755 | ||
6844c09d ACM |
1756 | event->header_size = size; |
1757 | } | |
1758 | ||
a723968c PZ |
1759 | /* |
1760 | * Called at perf_event creation and when events are attached/detached from a | |
1761 | * group. | |
1762 | */ | |
1763 | static void perf_event__header_size(struct perf_event *event) | |
1764 | { | |
1765 | __perf_event_read_size(event, | |
1766 | event->group_leader->nr_siblings); | |
1767 | __perf_event_header_size(event, event->attr.sample_type); | |
1768 | } | |
1769 | ||
6844c09d ACM |
1770 | static void perf_event__id_header_size(struct perf_event *event) |
1771 | { | |
1772 | struct perf_sample_data *data; | |
1773 | u64 sample_type = event->attr.sample_type; | |
1774 | u16 size = 0; | |
1775 | ||
c320c7b7 ACM |
1776 | if (sample_type & PERF_SAMPLE_TID) |
1777 | size += sizeof(data->tid_entry); | |
1778 | ||
1779 | if (sample_type & PERF_SAMPLE_TIME) | |
1780 | size += sizeof(data->time); | |
1781 | ||
ff3d527c AH |
1782 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
1783 | size += sizeof(data->id); | |
1784 | ||
c320c7b7 ACM |
1785 | if (sample_type & PERF_SAMPLE_ID) |
1786 | size += sizeof(data->id); | |
1787 | ||
1788 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
1789 | size += sizeof(data->stream_id); | |
1790 | ||
1791 | if (sample_type & PERF_SAMPLE_CPU) | |
1792 | size += sizeof(data->cpu_entry); | |
1793 | ||
6844c09d | 1794 | event->id_header_size = size; |
c320c7b7 ACM |
1795 | } |
1796 | ||
a723968c PZ |
1797 | static bool perf_event_validate_size(struct perf_event *event) |
1798 | { | |
1799 | /* | |
1800 | * The values computed here will be over-written when we actually | |
1801 | * attach the event. | |
1802 | */ | |
1803 | __perf_event_read_size(event, event->group_leader->nr_siblings + 1); | |
1804 | __perf_event_header_size(event, event->attr.sample_type & ~PERF_SAMPLE_READ); | |
1805 | perf_event__id_header_size(event); | |
1806 | ||
1807 | /* | |
1808 | * Sum the lot; should not exceed the 64k limit we have on records. | |
1809 | * Conservative limit to allow for callchains and other variable fields. | |
1810 | */ | |
1811 | if (event->read_size + event->header_size + | |
1812 | event->id_header_size + sizeof(struct perf_event_header) >= 16*1024) | |
1813 | return false; | |
1814 | ||
1815 | return true; | |
1816 | } | |
1817 | ||
8a49542c PZ |
1818 | static void perf_group_attach(struct perf_event *event) |
1819 | { | |
c320c7b7 | 1820 | struct perf_event *group_leader = event->group_leader, *pos; |
8a49542c | 1821 | |
a76a82a3 PZ |
1822 | lockdep_assert_held(&event->ctx->lock); |
1823 | ||
74c3337c PZ |
1824 | /* |
1825 | * We can have double attach due to group movement in perf_event_open. | |
1826 | */ | |
1827 | if (event->attach_state & PERF_ATTACH_GROUP) | |
1828 | return; | |
1829 | ||
8a49542c PZ |
1830 | event->attach_state |= PERF_ATTACH_GROUP; |
1831 | ||
1832 | if (group_leader == event) | |
1833 | return; | |
1834 | ||
652884fe PZ |
1835 | WARN_ON_ONCE(group_leader->ctx != event->ctx); |
1836 | ||
4ff6a8de | 1837 | group_leader->group_caps &= event->event_caps; |
8a49542c | 1838 | |
8343aae6 | 1839 | list_add_tail(&event->sibling_list, &group_leader->sibling_list); |
8a49542c | 1840 | group_leader->nr_siblings++; |
c320c7b7 ACM |
1841 | |
1842 | perf_event__header_size(group_leader); | |
1843 | ||
edb39592 | 1844 | for_each_sibling_event(pos, group_leader) |
c320c7b7 | 1845 | perf_event__header_size(pos); |
8a49542c PZ |
1846 | } |
1847 | ||
a63eaf34 | 1848 | /* |
788faab7 | 1849 | * Remove an event from the lists for its context. |
fccc714b | 1850 | * Must be called with ctx->mutex and ctx->lock held. |
a63eaf34 | 1851 | */ |
04289bb9 | 1852 | static void |
cdd6c482 | 1853 | list_del_event(struct perf_event *event, struct perf_event_context *ctx) |
04289bb9 | 1854 | { |
652884fe PZ |
1855 | WARN_ON_ONCE(event->ctx != ctx); |
1856 | lockdep_assert_held(&ctx->lock); | |
1857 | ||
8a49542c PZ |
1858 | /* |
1859 | * We can have double detach due to exit/hot-unplug + close. | |
1860 | */ | |
1861 | if (!(event->attach_state & PERF_ATTACH_CONTEXT)) | |
a63eaf34 | 1862 | return; |
8a49542c PZ |
1863 | |
1864 | event->attach_state &= ~PERF_ATTACH_CONTEXT; | |
1865 | ||
db4a8356 | 1866 | list_update_cgroup_event(event, ctx, false); |
e5d1367f | 1867 | |
cdd6c482 IM |
1868 | ctx->nr_events--; |
1869 | if (event->attr.inherit_stat) | |
bfbd3381 | 1870 | ctx->nr_stat--; |
8bc20959 | 1871 | |
cdd6c482 | 1872 | list_del_rcu(&event->event_entry); |
04289bb9 | 1873 | |
8a49542c | 1874 | if (event->group_leader == event) |
8e1a2031 | 1875 | del_event_from_groups(event, ctx); |
5c148194 | 1876 | |
b2e74a26 SE |
1877 | /* |
1878 | * If event was in error state, then keep it | |
1879 | * that way, otherwise bogus counts will be | |
1880 | * returned on read(). The only way to get out | |
1881 | * of error state is by explicit re-enabling | |
1882 | * of the event | |
1883 | */ | |
1884 | if (event->state > PERF_EVENT_STATE_OFF) | |
0d3d73aa | 1885 | perf_event_set_state(event, PERF_EVENT_STATE_OFF); |
5a3126d4 PZ |
1886 | |
1887 | ctx->generation++; | |
050735b0 PZ |
1888 | } |
1889 | ||
8a49542c | 1890 | static void perf_group_detach(struct perf_event *event) |
050735b0 PZ |
1891 | { |
1892 | struct perf_event *sibling, *tmp; | |
6668128a | 1893 | struct perf_event_context *ctx = event->ctx; |
8a49542c | 1894 | |
6668128a | 1895 | lockdep_assert_held(&ctx->lock); |
a76a82a3 | 1896 | |
8a49542c PZ |
1897 | /* |
1898 | * We can have double detach due to exit/hot-unplug + close. | |
1899 | */ | |
1900 | if (!(event->attach_state & PERF_ATTACH_GROUP)) | |
1901 | return; | |
1902 | ||
1903 | event->attach_state &= ~PERF_ATTACH_GROUP; | |
1904 | ||
1905 | /* | |
1906 | * If this is a sibling, remove it from its group. | |
1907 | */ | |
1908 | if (event->group_leader != event) { | |
8343aae6 | 1909 | list_del_init(&event->sibling_list); |
8a49542c | 1910 | event->group_leader->nr_siblings--; |
c320c7b7 | 1911 | goto out; |
8a49542c PZ |
1912 | } |
1913 | ||
04289bb9 | 1914 | /* |
cdd6c482 IM |
1915 | * If this was a group event with sibling events then |
1916 | * upgrade the siblings to singleton events by adding them | |
8a49542c | 1917 | * to whatever list we are on. |
04289bb9 | 1918 | */ |
8343aae6 | 1919 | list_for_each_entry_safe(sibling, tmp, &event->sibling_list, sibling_list) { |
8e1a2031 | 1920 | |
04289bb9 | 1921 | sibling->group_leader = sibling; |
24868367 | 1922 | list_del_init(&sibling->sibling_list); |
d6f962b5 FW |
1923 | |
1924 | /* Inherit group flags from the previous leader */ | |
4ff6a8de | 1925 | sibling->group_caps = event->group_caps; |
652884fe | 1926 | |
8e1a2031 | 1927 | if (!RB_EMPTY_NODE(&event->group_node)) { |
8e1a2031 | 1928 | add_event_to_groups(sibling, event->ctx); |
6668128a PZ |
1929 | |
1930 | if (sibling->state == PERF_EVENT_STATE_ACTIVE) { | |
1931 | struct list_head *list = sibling->attr.pinned ? | |
1932 | &ctx->pinned_active : &ctx->flexible_active; | |
1933 | ||
1934 | list_add_tail(&sibling->active_list, list); | |
1935 | } | |
8e1a2031 AB |
1936 | } |
1937 | ||
652884fe | 1938 | WARN_ON_ONCE(sibling->ctx != event->ctx); |
04289bb9 | 1939 | } |
c320c7b7 ACM |
1940 | |
1941 | out: | |
1942 | perf_event__header_size(event->group_leader); | |
1943 | ||
edb39592 | 1944 | for_each_sibling_event(tmp, event->group_leader) |
c320c7b7 | 1945 | perf_event__header_size(tmp); |
04289bb9 IM |
1946 | } |
1947 | ||
fadfe7be JO |
1948 | static bool is_orphaned_event(struct perf_event *event) |
1949 | { | |
a69b0ca4 | 1950 | return event->state == PERF_EVENT_STATE_DEAD; |
fadfe7be JO |
1951 | } |
1952 | ||
2c81a647 | 1953 | static inline int __pmu_filter_match(struct perf_event *event) |
66eb579e MR |
1954 | { |
1955 | struct pmu *pmu = event->pmu; | |
1956 | return pmu->filter_match ? pmu->filter_match(event) : 1; | |
1957 | } | |
1958 | ||
2c81a647 MR |
1959 | /* |
1960 | * Check whether we should attempt to schedule an event group based on | |
1961 | * PMU-specific filtering. An event group can consist of HW and SW events, | |
1962 | * potentially with a SW leader, so we must check all the filters, to | |
1963 | * determine whether a group is schedulable: | |
1964 | */ | |
1965 | static inline int pmu_filter_match(struct perf_event *event) | |
1966 | { | |
edb39592 | 1967 | struct perf_event *sibling; |
2c81a647 MR |
1968 | |
1969 | if (!__pmu_filter_match(event)) | |
1970 | return 0; | |
1971 | ||
edb39592 PZ |
1972 | for_each_sibling_event(sibling, event) { |
1973 | if (!__pmu_filter_match(sibling)) | |
2c81a647 MR |
1974 | return 0; |
1975 | } | |
1976 | ||
1977 | return 1; | |
1978 | } | |
1979 | ||
fa66f07a SE |
1980 | static inline int |
1981 | event_filter_match(struct perf_event *event) | |
1982 | { | |
0b8f1e2e PZ |
1983 | return (event->cpu == -1 || event->cpu == smp_processor_id()) && |
1984 | perf_cgroup_match(event) && pmu_filter_match(event); | |
fa66f07a SE |
1985 | } |
1986 | ||
9ffcfa6f SE |
1987 | static void |
1988 | event_sched_out(struct perf_event *event, | |
3b6f9e5c | 1989 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 1990 | struct perf_event_context *ctx) |
3b6f9e5c | 1991 | { |
0d3d73aa | 1992 | enum perf_event_state state = PERF_EVENT_STATE_INACTIVE; |
652884fe PZ |
1993 | |
1994 | WARN_ON_ONCE(event->ctx != ctx); | |
1995 | lockdep_assert_held(&ctx->lock); | |
1996 | ||
cdd6c482 | 1997 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
9ffcfa6f | 1998 | return; |
3b6f9e5c | 1999 | |
6668128a PZ |
2000 | /* |
2001 | * Asymmetry; we only schedule events _IN_ through ctx_sched_in(), but | |
2002 | * we can schedule events _OUT_ individually through things like | |
2003 | * __perf_remove_from_context(). | |
2004 | */ | |
2005 | list_del_init(&event->active_list); | |
2006 | ||
44377277 AS |
2007 | perf_pmu_disable(event->pmu); |
2008 | ||
28a967c3 PZ |
2009 | event->pmu->del(event, 0); |
2010 | event->oncpu = -1; | |
0d3d73aa | 2011 | |
1d54ad94 PZ |
2012 | if (READ_ONCE(event->pending_disable) >= 0) { |
2013 | WRITE_ONCE(event->pending_disable, -1); | |
0d3d73aa | 2014 | state = PERF_EVENT_STATE_OFF; |
970892a9 | 2015 | } |
0d3d73aa | 2016 | perf_event_set_state(event, state); |
3b6f9e5c | 2017 | |
cdd6c482 | 2018 | if (!is_software_event(event)) |
3b6f9e5c | 2019 | cpuctx->active_oncpu--; |
2fde4f94 MR |
2020 | if (!--ctx->nr_active) |
2021 | perf_event_ctx_deactivate(ctx); | |
0f5a2601 PZ |
2022 | if (event->attr.freq && event->attr.sample_freq) |
2023 | ctx->nr_freq--; | |
cdd6c482 | 2024 | if (event->attr.exclusive || !cpuctx->active_oncpu) |
3b6f9e5c | 2025 | cpuctx->exclusive = 0; |
44377277 AS |
2026 | |
2027 | perf_pmu_enable(event->pmu); | |
3b6f9e5c PM |
2028 | } |
2029 | ||
d859e29f | 2030 | static void |
cdd6c482 | 2031 | group_sched_out(struct perf_event *group_event, |
d859e29f | 2032 | struct perf_cpu_context *cpuctx, |
cdd6c482 | 2033 | struct perf_event_context *ctx) |
d859e29f | 2034 | { |
cdd6c482 | 2035 | struct perf_event *event; |
0d3d73aa PZ |
2036 | |
2037 | if (group_event->state != PERF_EVENT_STATE_ACTIVE) | |
2038 | return; | |
d859e29f | 2039 | |
3f005e7d MR |
2040 | perf_pmu_disable(ctx->pmu); |
2041 | ||
cdd6c482 | 2042 | event_sched_out(group_event, cpuctx, ctx); |
d859e29f PM |
2043 | |
2044 | /* | |
2045 | * Schedule out siblings (if any): | |
2046 | */ | |
edb39592 | 2047 | for_each_sibling_event(event, group_event) |
cdd6c482 | 2048 | event_sched_out(event, cpuctx, ctx); |
d859e29f | 2049 | |
3f005e7d MR |
2050 | perf_pmu_enable(ctx->pmu); |
2051 | ||
0d3d73aa | 2052 | if (group_event->attr.exclusive) |
d859e29f PM |
2053 | cpuctx->exclusive = 0; |
2054 | } | |
2055 | ||
45a0e07a | 2056 | #define DETACH_GROUP 0x01UL |
0017960f | 2057 | |
0793a61d | 2058 | /* |
cdd6c482 | 2059 | * Cross CPU call to remove a performance event |
0793a61d | 2060 | * |
cdd6c482 | 2061 | * We disable the event on the hardware level first. After that we |
0793a61d TG |
2062 | * remove it from the context list. |
2063 | */ | |
fae3fde6 PZ |
2064 | static void |
2065 | __perf_remove_from_context(struct perf_event *event, | |
2066 | struct perf_cpu_context *cpuctx, | |
2067 | struct perf_event_context *ctx, | |
2068 | void *info) | |
0793a61d | 2069 | { |
45a0e07a | 2070 | unsigned long flags = (unsigned long)info; |
0793a61d | 2071 | |
3c5c8711 PZ |
2072 | if (ctx->is_active & EVENT_TIME) { |
2073 | update_context_time(ctx); | |
2074 | update_cgrp_time_from_cpuctx(cpuctx); | |
2075 | } | |
2076 | ||
cdd6c482 | 2077 | event_sched_out(event, cpuctx, ctx); |
45a0e07a | 2078 | if (flags & DETACH_GROUP) |
46ce0fe9 | 2079 | perf_group_detach(event); |
cdd6c482 | 2080 | list_del_event(event, ctx); |
39a43640 PZ |
2081 | |
2082 | if (!ctx->nr_events && ctx->is_active) { | |
64ce3126 | 2083 | ctx->is_active = 0; |
39a43640 PZ |
2084 | if (ctx->task) { |
2085 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
2086 | cpuctx->task_ctx = NULL; | |
2087 | } | |
64ce3126 | 2088 | } |
0793a61d TG |
2089 | } |
2090 | ||
0793a61d | 2091 | /* |
cdd6c482 | 2092 | * Remove the event from a task's (or a CPU's) list of events. |
0793a61d | 2093 | * |
cdd6c482 IM |
2094 | * If event->ctx is a cloned context, callers must make sure that |
2095 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 PM |
2096 | * remains valid. This is OK when called from perf_release since |
2097 | * that only calls us on the top-level context, which can't be a clone. | |
cdd6c482 | 2098 | * When called from perf_event_exit_task, it's OK because the |
c93f7669 | 2099 | * context has been detached from its task. |
0793a61d | 2100 | */ |
45a0e07a | 2101 | static void perf_remove_from_context(struct perf_event *event, unsigned long flags) |
0793a61d | 2102 | { |
a76a82a3 PZ |
2103 | struct perf_event_context *ctx = event->ctx; |
2104 | ||
2105 | lockdep_assert_held(&ctx->mutex); | |
0793a61d | 2106 | |
45a0e07a | 2107 | event_function_call(event, __perf_remove_from_context, (void *)flags); |
a76a82a3 PZ |
2108 | |
2109 | /* | |
2110 | * The above event_function_call() can NO-OP when it hits | |
2111 | * TASK_TOMBSTONE. In that case we must already have been detached | |
2112 | * from the context (by perf_event_exit_event()) but the grouping | |
2113 | * might still be in-tact. | |
2114 | */ | |
2115 | WARN_ON_ONCE(event->attach_state & PERF_ATTACH_CONTEXT); | |
2116 | if ((flags & DETACH_GROUP) && | |
2117 | (event->attach_state & PERF_ATTACH_GROUP)) { | |
2118 | /* | |
2119 | * Since in that case we cannot possibly be scheduled, simply | |
2120 | * detach now. | |
2121 | */ | |
2122 | raw_spin_lock_irq(&ctx->lock); | |
2123 | perf_group_detach(event); | |
2124 | raw_spin_unlock_irq(&ctx->lock); | |
2125 | } | |
0793a61d TG |
2126 | } |
2127 | ||
d859e29f | 2128 | /* |
cdd6c482 | 2129 | * Cross CPU call to disable a performance event |
d859e29f | 2130 | */ |
fae3fde6 PZ |
2131 | static void __perf_event_disable(struct perf_event *event, |
2132 | struct perf_cpu_context *cpuctx, | |
2133 | struct perf_event_context *ctx, | |
2134 | void *info) | |
7b648018 | 2135 | { |
fae3fde6 PZ |
2136 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
2137 | return; | |
7b648018 | 2138 | |
3c5c8711 PZ |
2139 | if (ctx->is_active & EVENT_TIME) { |
2140 | update_context_time(ctx); | |
2141 | update_cgrp_time_from_event(event); | |
2142 | } | |
2143 | ||
fae3fde6 PZ |
2144 | if (event == event->group_leader) |
2145 | group_sched_out(event, cpuctx, ctx); | |
2146 | else | |
2147 | event_sched_out(event, cpuctx, ctx); | |
0d3d73aa PZ |
2148 | |
2149 | perf_event_set_state(event, PERF_EVENT_STATE_OFF); | |
7b648018 PZ |
2150 | } |
2151 | ||
d859e29f | 2152 | /* |
788faab7 | 2153 | * Disable an event. |
c93f7669 | 2154 | * |
cdd6c482 IM |
2155 | * If event->ctx is a cloned context, callers must make sure that |
2156 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 2157 | * remains valid. This condition is satisifed when called through |
cdd6c482 IM |
2158 | * perf_event_for_each_child or perf_event_for_each because they |
2159 | * hold the top-level event's child_mutex, so any descendant that | |
8ba289b8 PZ |
2160 | * goes to exit will block in perf_event_exit_event(). |
2161 | * | |
cdd6c482 | 2162 | * When called from perf_pending_event it's OK because event->ctx |
c93f7669 | 2163 | * is the current context on this CPU and preemption is disabled, |
cdd6c482 | 2164 | * hence we can't get into perf_event_task_sched_out for this context. |
d859e29f | 2165 | */ |
f63a8daa | 2166 | static void _perf_event_disable(struct perf_event *event) |
d859e29f | 2167 | { |
cdd6c482 | 2168 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 2169 | |
e625cce1 | 2170 | raw_spin_lock_irq(&ctx->lock); |
7b648018 | 2171 | if (event->state <= PERF_EVENT_STATE_OFF) { |
e625cce1 | 2172 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 2173 | return; |
53cfbf59 | 2174 | } |
e625cce1 | 2175 | raw_spin_unlock_irq(&ctx->lock); |
7b648018 | 2176 | |
fae3fde6 PZ |
2177 | event_function_call(event, __perf_event_disable, NULL); |
2178 | } | |
2179 | ||
2180 | void perf_event_disable_local(struct perf_event *event) | |
2181 | { | |
2182 | event_function_local(event, __perf_event_disable, NULL); | |
d859e29f | 2183 | } |
f63a8daa PZ |
2184 | |
2185 | /* | |
2186 | * Strictly speaking kernel users cannot create groups and therefore this | |
2187 | * interface does not need the perf_event_ctx_lock() magic. | |
2188 | */ | |
2189 | void perf_event_disable(struct perf_event *event) | |
2190 | { | |
2191 | struct perf_event_context *ctx; | |
2192 | ||
2193 | ctx = perf_event_ctx_lock(event); | |
2194 | _perf_event_disable(event); | |
2195 | perf_event_ctx_unlock(event, ctx); | |
2196 | } | |
dcfce4a0 | 2197 | EXPORT_SYMBOL_GPL(perf_event_disable); |
d859e29f | 2198 | |
5aab90ce JO |
2199 | void perf_event_disable_inatomic(struct perf_event *event) |
2200 | { | |
1d54ad94 PZ |
2201 | WRITE_ONCE(event->pending_disable, smp_processor_id()); |
2202 | /* can fail, see perf_pending_event_disable() */ | |
5aab90ce JO |
2203 | irq_work_queue(&event->pending); |
2204 | } | |
2205 | ||
e5d1367f | 2206 | static void perf_set_shadow_time(struct perf_event *event, |
0d3d73aa | 2207 | struct perf_event_context *ctx) |
e5d1367f SE |
2208 | { |
2209 | /* | |
2210 | * use the correct time source for the time snapshot | |
2211 | * | |
2212 | * We could get by without this by leveraging the | |
2213 | * fact that to get to this function, the caller | |
2214 | * has most likely already called update_context_time() | |
2215 | * and update_cgrp_time_xx() and thus both timestamp | |
2216 | * are identical (or very close). Given that tstamp is, | |
2217 | * already adjusted for cgroup, we could say that: | |
2218 | * tstamp - ctx->timestamp | |
2219 | * is equivalent to | |
2220 | * tstamp - cgrp->timestamp. | |
2221 | * | |
2222 | * Then, in perf_output_read(), the calculation would | |
2223 | * work with no changes because: | |
2224 | * - event is guaranteed scheduled in | |
2225 | * - no scheduled out in between | |
2226 | * - thus the timestamp would be the same | |
2227 | * | |
2228 | * But this is a bit hairy. | |
2229 | * | |
2230 | * So instead, we have an explicit cgroup call to remain | |
2231 | * within the time time source all along. We believe it | |
2232 | * is cleaner and simpler to understand. | |
2233 | */ | |
2234 | if (is_cgroup_event(event)) | |
0d3d73aa | 2235 | perf_cgroup_set_shadow_time(event, event->tstamp); |
e5d1367f | 2236 | else |
0d3d73aa | 2237 | event->shadow_ctx_time = event->tstamp - ctx->timestamp; |
e5d1367f SE |
2238 | } |
2239 | ||
4fe757dd PZ |
2240 | #define MAX_INTERRUPTS (~0ULL) |
2241 | ||
2242 | static void perf_log_throttle(struct perf_event *event, int enable); | |
ec0d7729 | 2243 | static void perf_log_itrace_start(struct perf_event *event); |
4fe757dd | 2244 | |
235c7fc7 | 2245 | static int |
9ffcfa6f | 2246 | event_sched_in(struct perf_event *event, |
235c7fc7 | 2247 | struct perf_cpu_context *cpuctx, |
6e37738a | 2248 | struct perf_event_context *ctx) |
235c7fc7 | 2249 | { |
44377277 | 2250 | int ret = 0; |
4158755d | 2251 | |
63342411 PZ |
2252 | lockdep_assert_held(&ctx->lock); |
2253 | ||
cdd6c482 | 2254 | if (event->state <= PERF_EVENT_STATE_OFF) |
235c7fc7 IM |
2255 | return 0; |
2256 | ||
95ff4ca2 AS |
2257 | WRITE_ONCE(event->oncpu, smp_processor_id()); |
2258 | /* | |
0c1cbc18 PZ |
2259 | * Order event::oncpu write to happen before the ACTIVE state is |
2260 | * visible. This allows perf_event_{stop,read}() to observe the correct | |
2261 | * ->oncpu if it sees ACTIVE. | |
95ff4ca2 AS |
2262 | */ |
2263 | smp_wmb(); | |
0d3d73aa | 2264 | perf_event_set_state(event, PERF_EVENT_STATE_ACTIVE); |
4fe757dd PZ |
2265 | |
2266 | /* | |
2267 | * Unthrottle events, since we scheduled we might have missed several | |
2268 | * ticks already, also for a heavily scheduling task there is little | |
2269 | * guarantee it'll get a tick in a timely manner. | |
2270 | */ | |
2271 | if (unlikely(event->hw.interrupts == MAX_INTERRUPTS)) { | |
2272 | perf_log_throttle(event, 1); | |
2273 | event->hw.interrupts = 0; | |
2274 | } | |
2275 | ||
44377277 AS |
2276 | perf_pmu_disable(event->pmu); |
2277 | ||
0d3d73aa | 2278 | perf_set_shadow_time(event, ctx); |
72f669c0 | 2279 | |
ec0d7729 AS |
2280 | perf_log_itrace_start(event); |
2281 | ||
a4eaf7f1 | 2282 | if (event->pmu->add(event, PERF_EF_START)) { |
0d3d73aa | 2283 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
cdd6c482 | 2284 | event->oncpu = -1; |
44377277 AS |
2285 | ret = -EAGAIN; |
2286 | goto out; | |
235c7fc7 IM |
2287 | } |
2288 | ||
cdd6c482 | 2289 | if (!is_software_event(event)) |
3b6f9e5c | 2290 | cpuctx->active_oncpu++; |
2fde4f94 MR |
2291 | if (!ctx->nr_active++) |
2292 | perf_event_ctx_activate(ctx); | |
0f5a2601 PZ |
2293 | if (event->attr.freq && event->attr.sample_freq) |
2294 | ctx->nr_freq++; | |
235c7fc7 | 2295 | |
cdd6c482 | 2296 | if (event->attr.exclusive) |
3b6f9e5c PM |
2297 | cpuctx->exclusive = 1; |
2298 | ||
44377277 AS |
2299 | out: |
2300 | perf_pmu_enable(event->pmu); | |
2301 | ||
2302 | return ret; | |
235c7fc7 IM |
2303 | } |
2304 | ||
6751b71e | 2305 | static int |
cdd6c482 | 2306 | group_sched_in(struct perf_event *group_event, |
6751b71e | 2307 | struct perf_cpu_context *cpuctx, |
6e37738a | 2308 | struct perf_event_context *ctx) |
6751b71e | 2309 | { |
6bde9b6c | 2310 | struct perf_event *event, *partial_group = NULL; |
4a234593 | 2311 | struct pmu *pmu = ctx->pmu; |
6751b71e | 2312 | |
cdd6c482 | 2313 | if (group_event->state == PERF_EVENT_STATE_OFF) |
6751b71e PM |
2314 | return 0; |
2315 | ||
fbbe0701 | 2316 | pmu->start_txn(pmu, PERF_PMU_TXN_ADD); |
6bde9b6c | 2317 | |
9ffcfa6f | 2318 | if (event_sched_in(group_event, cpuctx, ctx)) { |
ad5133b7 | 2319 | pmu->cancel_txn(pmu); |
272325c4 | 2320 | perf_mux_hrtimer_restart(cpuctx); |
6751b71e | 2321 | return -EAGAIN; |
90151c35 | 2322 | } |
6751b71e PM |
2323 | |
2324 | /* | |
2325 | * Schedule in siblings as one group (if any): | |
2326 | */ | |
edb39592 | 2327 | for_each_sibling_event(event, group_event) { |
9ffcfa6f | 2328 | if (event_sched_in(event, cpuctx, ctx)) { |
cdd6c482 | 2329 | partial_group = event; |
6751b71e PM |
2330 | goto group_error; |
2331 | } | |
2332 | } | |
2333 | ||
9ffcfa6f | 2334 | if (!pmu->commit_txn(pmu)) |
6e85158c | 2335 | return 0; |
9ffcfa6f | 2336 | |
6751b71e PM |
2337 | group_error: |
2338 | /* | |
2339 | * Groups can be scheduled in as one unit only, so undo any | |
2340 | * partial group before returning: | |
0d3d73aa | 2341 | * The events up to the failed event are scheduled out normally. |
6751b71e | 2342 | */ |
edb39592 | 2343 | for_each_sibling_event(event, group_event) { |
cdd6c482 | 2344 | if (event == partial_group) |
0d3d73aa | 2345 | break; |
d7842da4 | 2346 | |
0d3d73aa | 2347 | event_sched_out(event, cpuctx, ctx); |
6751b71e | 2348 | } |
9ffcfa6f | 2349 | event_sched_out(group_event, cpuctx, ctx); |
6751b71e | 2350 | |
ad5133b7 | 2351 | pmu->cancel_txn(pmu); |
90151c35 | 2352 | |
272325c4 | 2353 | perf_mux_hrtimer_restart(cpuctx); |
9e630205 | 2354 | |
6751b71e PM |
2355 | return -EAGAIN; |
2356 | } | |
2357 | ||
3b6f9e5c | 2358 | /* |
cdd6c482 | 2359 | * Work out whether we can put this event group on the CPU now. |
3b6f9e5c | 2360 | */ |
cdd6c482 | 2361 | static int group_can_go_on(struct perf_event *event, |
3b6f9e5c PM |
2362 | struct perf_cpu_context *cpuctx, |
2363 | int can_add_hw) | |
2364 | { | |
2365 | /* | |
cdd6c482 | 2366 | * Groups consisting entirely of software events can always go on. |
3b6f9e5c | 2367 | */ |
4ff6a8de | 2368 | if (event->group_caps & PERF_EV_CAP_SOFTWARE) |
3b6f9e5c PM |
2369 | return 1; |
2370 | /* | |
2371 | * If an exclusive group is already on, no other hardware | |
cdd6c482 | 2372 | * events can go on. |
3b6f9e5c PM |
2373 | */ |
2374 | if (cpuctx->exclusive) | |
2375 | return 0; | |
2376 | /* | |
2377 | * If this group is exclusive and there are already | |
cdd6c482 | 2378 | * events on the CPU, it can't go on. |
3b6f9e5c | 2379 | */ |
cdd6c482 | 2380 | if (event->attr.exclusive && cpuctx->active_oncpu) |
3b6f9e5c PM |
2381 | return 0; |
2382 | /* | |
2383 | * Otherwise, try to add it if all previous groups were able | |
2384 | * to go on. | |
2385 | */ | |
2386 | return can_add_hw; | |
2387 | } | |
2388 | ||
cdd6c482 IM |
2389 | static void add_event_to_ctx(struct perf_event *event, |
2390 | struct perf_event_context *ctx) | |
53cfbf59 | 2391 | { |
cdd6c482 | 2392 | list_add_event(event, ctx); |
8a49542c | 2393 | perf_group_attach(event); |
53cfbf59 PM |
2394 | } |
2395 | ||
bd2afa49 PZ |
2396 | static void ctx_sched_out(struct perf_event_context *ctx, |
2397 | struct perf_cpu_context *cpuctx, | |
2398 | enum event_type_t event_type); | |
2c29ef0f PZ |
2399 | static void |
2400 | ctx_sched_in(struct perf_event_context *ctx, | |
2401 | struct perf_cpu_context *cpuctx, | |
2402 | enum event_type_t event_type, | |
2403 | struct task_struct *task); | |
fe4b04fa | 2404 | |
bd2afa49 | 2405 | static void task_ctx_sched_out(struct perf_cpu_context *cpuctx, |
487f05e1 AS |
2406 | struct perf_event_context *ctx, |
2407 | enum event_type_t event_type) | |
bd2afa49 PZ |
2408 | { |
2409 | if (!cpuctx->task_ctx) | |
2410 | return; | |
2411 | ||
2412 | if (WARN_ON_ONCE(ctx != cpuctx->task_ctx)) | |
2413 | return; | |
2414 | ||
487f05e1 | 2415 | ctx_sched_out(ctx, cpuctx, event_type); |
bd2afa49 PZ |
2416 | } |
2417 | ||
dce5855b PZ |
2418 | static void perf_event_sched_in(struct perf_cpu_context *cpuctx, |
2419 | struct perf_event_context *ctx, | |
2420 | struct task_struct *task) | |
2421 | { | |
2422 | cpu_ctx_sched_in(cpuctx, EVENT_PINNED, task); | |
2423 | if (ctx) | |
2424 | ctx_sched_in(ctx, cpuctx, EVENT_PINNED, task); | |
2425 | cpu_ctx_sched_in(cpuctx, EVENT_FLEXIBLE, task); | |
2426 | if (ctx) | |
2427 | ctx_sched_in(ctx, cpuctx, EVENT_FLEXIBLE, task); | |
2428 | } | |
2429 | ||
487f05e1 AS |
2430 | /* |
2431 | * We want to maintain the following priority of scheduling: | |
2432 | * - CPU pinned (EVENT_CPU | EVENT_PINNED) | |
2433 | * - task pinned (EVENT_PINNED) | |
2434 | * - CPU flexible (EVENT_CPU | EVENT_FLEXIBLE) | |
2435 | * - task flexible (EVENT_FLEXIBLE). | |
2436 | * | |
2437 | * In order to avoid unscheduling and scheduling back in everything every | |
2438 | * time an event is added, only do it for the groups of equal priority and | |
2439 | * below. | |
2440 | * | |
2441 | * This can be called after a batch operation on task events, in which case | |
2442 | * event_type is a bit mask of the types of events involved. For CPU events, | |
2443 | * event_type is only either EVENT_PINNED or EVENT_FLEXIBLE. | |
2444 | */ | |
3e349507 | 2445 | static void ctx_resched(struct perf_cpu_context *cpuctx, |
487f05e1 AS |
2446 | struct perf_event_context *task_ctx, |
2447 | enum event_type_t event_type) | |
0017960f | 2448 | { |
bd903afe | 2449 | enum event_type_t ctx_event_type; |
487f05e1 AS |
2450 | bool cpu_event = !!(event_type & EVENT_CPU); |
2451 | ||
2452 | /* | |
2453 | * If pinned groups are involved, flexible groups also need to be | |
2454 | * scheduled out. | |
2455 | */ | |
2456 | if (event_type & EVENT_PINNED) | |
2457 | event_type |= EVENT_FLEXIBLE; | |
2458 | ||
bd903afe SL |
2459 | ctx_event_type = event_type & EVENT_ALL; |
2460 | ||
3e349507 PZ |
2461 | perf_pmu_disable(cpuctx->ctx.pmu); |
2462 | if (task_ctx) | |
487f05e1 AS |
2463 | task_ctx_sched_out(cpuctx, task_ctx, event_type); |
2464 | ||
2465 | /* | |
2466 | * Decide which cpu ctx groups to schedule out based on the types | |
2467 | * of events that caused rescheduling: | |
2468 | * - EVENT_CPU: schedule out corresponding groups; | |
2469 | * - EVENT_PINNED task events: schedule out EVENT_FLEXIBLE groups; | |
2470 | * - otherwise, do nothing more. | |
2471 | */ | |
2472 | if (cpu_event) | |
2473 | cpu_ctx_sched_out(cpuctx, ctx_event_type); | |
2474 | else if (ctx_event_type & EVENT_PINNED) | |
2475 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
2476 | ||
3e349507 PZ |
2477 | perf_event_sched_in(cpuctx, task_ctx, current); |
2478 | perf_pmu_enable(cpuctx->ctx.pmu); | |
0017960f PZ |
2479 | } |
2480 | ||
c68d224e SE |
2481 | void perf_pmu_resched(struct pmu *pmu) |
2482 | { | |
2483 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); | |
2484 | struct perf_event_context *task_ctx = cpuctx->task_ctx; | |
2485 | ||
2486 | perf_ctx_lock(cpuctx, task_ctx); | |
2487 | ctx_resched(cpuctx, task_ctx, EVENT_ALL|EVENT_CPU); | |
2488 | perf_ctx_unlock(cpuctx, task_ctx); | |
2489 | } | |
2490 | ||
0793a61d | 2491 | /* |
cdd6c482 | 2492 | * Cross CPU call to install and enable a performance event |
682076ae | 2493 | * |
a096309b PZ |
2494 | * Very similar to remote_function() + event_function() but cannot assume that |
2495 | * things like ctx->is_active and cpuctx->task_ctx are set. | |
0793a61d | 2496 | */ |
fe4b04fa | 2497 | static int __perf_install_in_context(void *info) |
0793a61d | 2498 | { |
a096309b PZ |
2499 | struct perf_event *event = info; |
2500 | struct perf_event_context *ctx = event->ctx; | |
108b02cf | 2501 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
2c29ef0f | 2502 | struct perf_event_context *task_ctx = cpuctx->task_ctx; |
63cae12b | 2503 | bool reprogram = true; |
a096309b | 2504 | int ret = 0; |
0793a61d | 2505 | |
63b6da39 | 2506 | raw_spin_lock(&cpuctx->ctx.lock); |
39a43640 | 2507 | if (ctx->task) { |
b58f6b0d PZ |
2508 | raw_spin_lock(&ctx->lock); |
2509 | task_ctx = ctx; | |
a096309b | 2510 | |
63cae12b | 2511 | reprogram = (ctx->task == current); |
b58f6b0d | 2512 | |
39a43640 | 2513 | /* |
63cae12b PZ |
2514 | * If the task is running, it must be running on this CPU, |
2515 | * otherwise we cannot reprogram things. | |
2516 | * | |
2517 | * If its not running, we don't care, ctx->lock will | |
2518 | * serialize against it becoming runnable. | |
39a43640 | 2519 | */ |
63cae12b PZ |
2520 | if (task_curr(ctx->task) && !reprogram) { |
2521 | ret = -ESRCH; | |
2522 | goto unlock; | |
2523 | } | |
a096309b | 2524 | |
63cae12b | 2525 | WARN_ON_ONCE(reprogram && cpuctx->task_ctx && cpuctx->task_ctx != ctx); |
63b6da39 PZ |
2526 | } else if (task_ctx) { |
2527 | raw_spin_lock(&task_ctx->lock); | |
2c29ef0f | 2528 | } |
b58f6b0d | 2529 | |
33801b94 | 2530 | #ifdef CONFIG_CGROUP_PERF |
2531 | if (is_cgroup_event(event)) { | |
2532 | /* | |
2533 | * If the current cgroup doesn't match the event's | |
2534 | * cgroup, we should not try to schedule it. | |
2535 | */ | |
2536 | struct perf_cgroup *cgrp = perf_cgroup_from_task(current, ctx); | |
2537 | reprogram = cgroup_is_descendant(cgrp->css.cgroup, | |
2538 | event->cgrp->css.cgroup); | |
2539 | } | |
2540 | #endif | |
2541 | ||
63cae12b | 2542 | if (reprogram) { |
a096309b PZ |
2543 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
2544 | add_event_to_ctx(event, ctx); | |
487f05e1 | 2545 | ctx_resched(cpuctx, task_ctx, get_event_type(event)); |
a096309b PZ |
2546 | } else { |
2547 | add_event_to_ctx(event, ctx); | |
2548 | } | |
2549 | ||
63b6da39 | 2550 | unlock: |
2c29ef0f | 2551 | perf_ctx_unlock(cpuctx, task_ctx); |
fe4b04fa | 2552 | |
a096309b | 2553 | return ret; |
0793a61d TG |
2554 | } |
2555 | ||
8a58ddae AS |
2556 | static bool exclusive_event_installable(struct perf_event *event, |
2557 | struct perf_event_context *ctx); | |
2558 | ||
0793a61d | 2559 | /* |
a096309b PZ |
2560 | * Attach a performance event to a context. |
2561 | * | |
2562 | * Very similar to event_function_call, see comment there. | |
0793a61d TG |
2563 | */ |
2564 | static void | |
cdd6c482 IM |
2565 | perf_install_in_context(struct perf_event_context *ctx, |
2566 | struct perf_event *event, | |
0793a61d TG |
2567 | int cpu) |
2568 | { | |
a096309b | 2569 | struct task_struct *task = READ_ONCE(ctx->task); |
39a43640 | 2570 | |
fe4b04fa PZ |
2571 | lockdep_assert_held(&ctx->mutex); |
2572 | ||
8a58ddae AS |
2573 | WARN_ON_ONCE(!exclusive_event_installable(event, ctx)); |
2574 | ||
0cda4c02 YZ |
2575 | if (event->cpu != -1) |
2576 | event->cpu = cpu; | |
c3f00c70 | 2577 | |
0b8f1e2e PZ |
2578 | /* |
2579 | * Ensures that if we can observe event->ctx, both the event and ctx | |
2580 | * will be 'complete'. See perf_iterate_sb_cpu(). | |
2581 | */ | |
2582 | smp_store_release(&event->ctx, ctx); | |
2583 | ||
a096309b PZ |
2584 | if (!task) { |
2585 | cpu_function_call(cpu, __perf_install_in_context, event); | |
2586 | return; | |
2587 | } | |
2588 | ||
2589 | /* | |
2590 | * Should not happen, we validate the ctx is still alive before calling. | |
2591 | */ | |
2592 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) | |
2593 | return; | |
2594 | ||
39a43640 PZ |
2595 | /* |
2596 | * Installing events is tricky because we cannot rely on ctx->is_active | |
2597 | * to be set in case this is the nr_events 0 -> 1 transition. | |
63cae12b PZ |
2598 | * |
2599 | * Instead we use task_curr(), which tells us if the task is running. | |
2600 | * However, since we use task_curr() outside of rq::lock, we can race | |
2601 | * against the actual state. This means the result can be wrong. | |
2602 | * | |
2603 | * If we get a false positive, we retry, this is harmless. | |
2604 | * | |
2605 | * If we get a false negative, things are complicated. If we are after | |
2606 | * perf_event_context_sched_in() ctx::lock will serialize us, and the | |
2607 | * value must be correct. If we're before, it doesn't matter since | |
2608 | * perf_event_context_sched_in() will program the counter. | |
2609 | * | |
2610 | * However, this hinges on the remote context switch having observed | |
2611 | * our task->perf_event_ctxp[] store, such that it will in fact take | |
2612 | * ctx::lock in perf_event_context_sched_in(). | |
2613 | * | |
2614 | * We do this by task_function_call(), if the IPI fails to hit the task | |
2615 | * we know any future context switch of task must see the | |
2616 | * perf_event_ctpx[] store. | |
39a43640 | 2617 | */ |
63cae12b | 2618 | |
63b6da39 | 2619 | /* |
63cae12b PZ |
2620 | * This smp_mb() orders the task->perf_event_ctxp[] store with the |
2621 | * task_cpu() load, such that if the IPI then does not find the task | |
2622 | * running, a future context switch of that task must observe the | |
2623 | * store. | |
63b6da39 | 2624 | */ |
63cae12b PZ |
2625 | smp_mb(); |
2626 | again: | |
2627 | if (!task_function_call(task, __perf_install_in_context, event)) | |
a096309b PZ |
2628 | return; |
2629 | ||
2630 | raw_spin_lock_irq(&ctx->lock); | |
2631 | task = ctx->task; | |
84c4e620 | 2632 | if (WARN_ON_ONCE(task == TASK_TOMBSTONE)) { |
a096309b PZ |
2633 | /* |
2634 | * Cannot happen because we already checked above (which also | |
2635 | * cannot happen), and we hold ctx->mutex, which serializes us | |
2636 | * against perf_event_exit_task_context(). | |
2637 | */ | |
63b6da39 PZ |
2638 | raw_spin_unlock_irq(&ctx->lock); |
2639 | return; | |
2640 | } | |
39a43640 | 2641 | /* |
63cae12b PZ |
2642 | * If the task is not running, ctx->lock will avoid it becoming so, |
2643 | * thus we can safely install the event. | |
39a43640 | 2644 | */ |
63cae12b PZ |
2645 | if (task_curr(task)) { |
2646 | raw_spin_unlock_irq(&ctx->lock); | |
2647 | goto again; | |
2648 | } | |
2649 | add_event_to_ctx(event, ctx); | |
2650 | raw_spin_unlock_irq(&ctx->lock); | |
0793a61d TG |
2651 | } |
2652 | ||
d859e29f | 2653 | /* |
cdd6c482 | 2654 | * Cross CPU call to enable a performance event |
d859e29f | 2655 | */ |
fae3fde6 PZ |
2656 | static void __perf_event_enable(struct perf_event *event, |
2657 | struct perf_cpu_context *cpuctx, | |
2658 | struct perf_event_context *ctx, | |
2659 | void *info) | |
04289bb9 | 2660 | { |
cdd6c482 | 2661 | struct perf_event *leader = event->group_leader; |
fae3fde6 | 2662 | struct perf_event_context *task_ctx; |
04289bb9 | 2663 | |
6e801e01 PZ |
2664 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2665 | event->state <= PERF_EVENT_STATE_ERROR) | |
fae3fde6 | 2666 | return; |
3cbed429 | 2667 | |
bd2afa49 PZ |
2668 | if (ctx->is_active) |
2669 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); | |
2670 | ||
0d3d73aa | 2671 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
04289bb9 | 2672 | |
fae3fde6 PZ |
2673 | if (!ctx->is_active) |
2674 | return; | |
2675 | ||
e5d1367f | 2676 | if (!event_filter_match(event)) { |
bd2afa49 | 2677 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); |
fae3fde6 | 2678 | return; |
e5d1367f | 2679 | } |
f4c4176f | 2680 | |
04289bb9 | 2681 | /* |
cdd6c482 | 2682 | * If the event is in a group and isn't the group leader, |
d859e29f | 2683 | * then don't put it on unless the group is on. |
04289bb9 | 2684 | */ |
bd2afa49 PZ |
2685 | if (leader != event && leader->state != PERF_EVENT_STATE_ACTIVE) { |
2686 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
fae3fde6 | 2687 | return; |
bd2afa49 | 2688 | } |
fe4b04fa | 2689 | |
fae3fde6 PZ |
2690 | task_ctx = cpuctx->task_ctx; |
2691 | if (ctx->task) | |
2692 | WARN_ON_ONCE(task_ctx != ctx); | |
d859e29f | 2693 | |
487f05e1 | 2694 | ctx_resched(cpuctx, task_ctx, get_event_type(event)); |
7b648018 PZ |
2695 | } |
2696 | ||
d859e29f | 2697 | /* |
788faab7 | 2698 | * Enable an event. |
c93f7669 | 2699 | * |
cdd6c482 IM |
2700 | * If event->ctx is a cloned context, callers must make sure that |
2701 | * every task struct that event->ctx->task could possibly point to | |
c93f7669 | 2702 | * remains valid. This condition is satisfied when called through |
cdd6c482 IM |
2703 | * perf_event_for_each_child or perf_event_for_each as described |
2704 | * for perf_event_disable. | |
d859e29f | 2705 | */ |
f63a8daa | 2706 | static void _perf_event_enable(struct perf_event *event) |
d859e29f | 2707 | { |
cdd6c482 | 2708 | struct perf_event_context *ctx = event->ctx; |
d859e29f | 2709 | |
7b648018 | 2710 | raw_spin_lock_irq(&ctx->lock); |
6e801e01 PZ |
2711 | if (event->state >= PERF_EVENT_STATE_INACTIVE || |
2712 | event->state < PERF_EVENT_STATE_ERROR) { | |
7b648018 | 2713 | raw_spin_unlock_irq(&ctx->lock); |
d859e29f PM |
2714 | return; |
2715 | } | |
2716 | ||
d859e29f | 2717 | /* |
cdd6c482 | 2718 | * If the event is in error state, clear that first. |
7b648018 PZ |
2719 | * |
2720 | * That way, if we see the event in error state below, we know that it | |
2721 | * has gone back into error state, as distinct from the task having | |
2722 | * been scheduled away before the cross-call arrived. | |
d859e29f | 2723 | */ |
cdd6c482 IM |
2724 | if (event->state == PERF_EVENT_STATE_ERROR) |
2725 | event->state = PERF_EVENT_STATE_OFF; | |
e625cce1 | 2726 | raw_spin_unlock_irq(&ctx->lock); |
fe4b04fa | 2727 | |
fae3fde6 | 2728 | event_function_call(event, __perf_event_enable, NULL); |
d859e29f | 2729 | } |
f63a8daa PZ |
2730 | |
2731 | /* | |
2732 | * See perf_event_disable(); | |
2733 | */ | |
2734 | void perf_event_enable(struct perf_event *event) | |
2735 | { | |
2736 | struct perf_event_context *ctx; | |
2737 | ||
2738 | ctx = perf_event_ctx_lock(event); | |
2739 | _perf_event_enable(event); | |
2740 | perf_event_ctx_unlock(event, ctx); | |
2741 | } | |
dcfce4a0 | 2742 | EXPORT_SYMBOL_GPL(perf_event_enable); |
d859e29f | 2743 | |
375637bc AS |
2744 | struct stop_event_data { |
2745 | struct perf_event *event; | |
2746 | unsigned int restart; | |
2747 | }; | |
2748 | ||
95ff4ca2 AS |
2749 | static int __perf_event_stop(void *info) |
2750 | { | |
375637bc AS |
2751 | struct stop_event_data *sd = info; |
2752 | struct perf_event *event = sd->event; | |
95ff4ca2 | 2753 | |
375637bc | 2754 | /* if it's already INACTIVE, do nothing */ |
95ff4ca2 AS |
2755 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) |
2756 | return 0; | |
2757 | ||
2758 | /* matches smp_wmb() in event_sched_in() */ | |
2759 | smp_rmb(); | |
2760 | ||
2761 | /* | |
2762 | * There is a window with interrupts enabled before we get here, | |
2763 | * so we need to check again lest we try to stop another CPU's event. | |
2764 | */ | |
2765 | if (READ_ONCE(event->oncpu) != smp_processor_id()) | |
2766 | return -EAGAIN; | |
2767 | ||
2768 | event->pmu->stop(event, PERF_EF_UPDATE); | |
2769 | ||
375637bc AS |
2770 | /* |
2771 | * May race with the actual stop (through perf_pmu_output_stop()), | |
2772 | * but it is only used for events with AUX ring buffer, and such | |
2773 | * events will refuse to restart because of rb::aux_mmap_count==0, | |
2774 | * see comments in perf_aux_output_begin(). | |
2775 | * | |
788faab7 | 2776 | * Since this is happening on an event-local CPU, no trace is lost |
375637bc AS |
2777 | * while restarting. |
2778 | */ | |
2779 | if (sd->restart) | |
c9bbdd48 | 2780 | event->pmu->start(event, 0); |
375637bc | 2781 | |
95ff4ca2 AS |
2782 | return 0; |
2783 | } | |
2784 | ||
767ae086 | 2785 | static int perf_event_stop(struct perf_event *event, int restart) |
375637bc AS |
2786 | { |
2787 | struct stop_event_data sd = { | |
2788 | .event = event, | |
767ae086 | 2789 | .restart = restart, |
375637bc AS |
2790 | }; |
2791 | int ret = 0; | |
2792 | ||
2793 | do { | |
2794 | if (READ_ONCE(event->state) != PERF_EVENT_STATE_ACTIVE) | |
2795 | return 0; | |
2796 | ||
2797 | /* matches smp_wmb() in event_sched_in() */ | |
2798 | smp_rmb(); | |
2799 | ||
2800 | /* | |
2801 | * We only want to restart ACTIVE events, so if the event goes | |
2802 | * inactive here (event->oncpu==-1), there's nothing more to do; | |
2803 | * fall through with ret==-ENXIO. | |
2804 | */ | |
2805 | ret = cpu_function_call(READ_ONCE(event->oncpu), | |
2806 | __perf_event_stop, &sd); | |
2807 | } while (ret == -EAGAIN); | |
2808 | ||
2809 | return ret; | |
2810 | } | |
2811 | ||
2812 | /* | |
2813 | * In order to contain the amount of racy and tricky in the address filter | |
2814 | * configuration management, it is a two part process: | |
2815 | * | |
2816 | * (p1) when userspace mappings change as a result of (1) or (2) or (3) below, | |
2817 | * we update the addresses of corresponding vmas in | |
c60f83b8 | 2818 | * event::addr_filter_ranges array and bump the event::addr_filters_gen; |
375637bc AS |
2819 | * (p2) when an event is scheduled in (pmu::add), it calls |
2820 | * perf_event_addr_filters_sync() which calls pmu::addr_filters_sync() | |
2821 | * if the generation has changed since the previous call. | |
2822 | * | |
2823 | * If (p1) happens while the event is active, we restart it to force (p2). | |
2824 | * | |
2825 | * (1) perf_addr_filters_apply(): adjusting filters' offsets based on | |
2826 | * pre-existing mappings, called once when new filters arrive via SET_FILTER | |
2827 | * ioctl; | |
2828 | * (2) perf_addr_filters_adjust(): adjusting filters' offsets based on newly | |
2829 | * registered mapping, called for every new mmap(), with mm::mmap_sem down | |
2830 | * for reading; | |
2831 | * (3) perf_event_addr_filters_exec(): clearing filters' offsets in the process | |
2832 | * of exec. | |
2833 | */ | |
2834 | void perf_event_addr_filters_sync(struct perf_event *event) | |
2835 | { | |
2836 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
2837 | ||
2838 | if (!has_addr_filter(event)) | |
2839 | return; | |
2840 | ||
2841 | raw_spin_lock(&ifh->lock); | |
2842 | if (event->addr_filters_gen != event->hw.addr_filters_gen) { | |
2843 | event->pmu->addr_filters_sync(event); | |
2844 | event->hw.addr_filters_gen = event->addr_filters_gen; | |
2845 | } | |
2846 | raw_spin_unlock(&ifh->lock); | |
2847 | } | |
2848 | EXPORT_SYMBOL_GPL(perf_event_addr_filters_sync); | |
2849 | ||
f63a8daa | 2850 | static int _perf_event_refresh(struct perf_event *event, int refresh) |
79f14641 | 2851 | { |
2023b359 | 2852 | /* |
cdd6c482 | 2853 | * not supported on inherited events |
2023b359 | 2854 | */ |
2e939d1d | 2855 | if (event->attr.inherit || !is_sampling_event(event)) |
2023b359 PZ |
2856 | return -EINVAL; |
2857 | ||
cdd6c482 | 2858 | atomic_add(refresh, &event->event_limit); |
f63a8daa | 2859 | _perf_event_enable(event); |
2023b359 PZ |
2860 | |
2861 | return 0; | |
79f14641 | 2862 | } |
f63a8daa PZ |
2863 | |
2864 | /* | |
2865 | * See perf_event_disable() | |
2866 | */ | |
2867 | int perf_event_refresh(struct perf_event *event, int refresh) | |
2868 | { | |
2869 | struct perf_event_context *ctx; | |
2870 | int ret; | |
2871 | ||
2872 | ctx = perf_event_ctx_lock(event); | |
2873 | ret = _perf_event_refresh(event, refresh); | |
2874 | perf_event_ctx_unlock(event, ctx); | |
2875 | ||
2876 | return ret; | |
2877 | } | |
26ca5c11 | 2878 | EXPORT_SYMBOL_GPL(perf_event_refresh); |
79f14641 | 2879 | |
32ff77e8 MC |
2880 | static int perf_event_modify_breakpoint(struct perf_event *bp, |
2881 | struct perf_event_attr *attr) | |
2882 | { | |
2883 | int err; | |
2884 | ||
2885 | _perf_event_disable(bp); | |
2886 | ||
2887 | err = modify_user_hw_breakpoint_check(bp, attr, true); | |
32ff77e8 | 2888 | |
bf06278c | 2889 | if (!bp->attr.disabled) |
32ff77e8 | 2890 | _perf_event_enable(bp); |
bf06278c JO |
2891 | |
2892 | return err; | |
32ff77e8 MC |
2893 | } |
2894 | ||
2895 | static int perf_event_modify_attr(struct perf_event *event, | |
2896 | struct perf_event_attr *attr) | |
2897 | { | |
2898 | if (event->attr.type != attr->type) | |
2899 | return -EINVAL; | |
2900 | ||
2901 | switch (event->attr.type) { | |
2902 | case PERF_TYPE_BREAKPOINT: | |
2903 | return perf_event_modify_breakpoint(event, attr); | |
2904 | default: | |
2905 | /* Place holder for future additions. */ | |
2906 | return -EOPNOTSUPP; | |
2907 | } | |
2908 | } | |
2909 | ||
5b0311e1 FW |
2910 | static void ctx_sched_out(struct perf_event_context *ctx, |
2911 | struct perf_cpu_context *cpuctx, | |
2912 | enum event_type_t event_type) | |
235c7fc7 | 2913 | { |
6668128a | 2914 | struct perf_event *event, *tmp; |
db24d33e | 2915 | int is_active = ctx->is_active; |
235c7fc7 | 2916 | |
c994d613 | 2917 | lockdep_assert_held(&ctx->lock); |
235c7fc7 | 2918 | |
39a43640 PZ |
2919 | if (likely(!ctx->nr_events)) { |
2920 | /* | |
2921 | * See __perf_remove_from_context(). | |
2922 | */ | |
2923 | WARN_ON_ONCE(ctx->is_active); | |
2924 | if (ctx->task) | |
2925 | WARN_ON_ONCE(cpuctx->task_ctx); | |
facc4307 | 2926 | return; |
39a43640 PZ |
2927 | } |
2928 | ||
db24d33e | 2929 | ctx->is_active &= ~event_type; |
3cbaa590 PZ |
2930 | if (!(ctx->is_active & EVENT_ALL)) |
2931 | ctx->is_active = 0; | |
2932 | ||
63e30d3e PZ |
2933 | if (ctx->task) { |
2934 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
2935 | if (!ctx->is_active) | |
2936 | cpuctx->task_ctx = NULL; | |
2937 | } | |
facc4307 | 2938 | |
8fdc6539 PZ |
2939 | /* |
2940 | * Always update time if it was set; not only when it changes. | |
2941 | * Otherwise we can 'forget' to update time for any but the last | |
2942 | * context we sched out. For example: | |
2943 | * | |
2944 | * ctx_sched_out(.event_type = EVENT_FLEXIBLE) | |
2945 | * ctx_sched_out(.event_type = EVENT_PINNED) | |
2946 | * | |
2947 | * would only update time for the pinned events. | |
2948 | */ | |
3cbaa590 PZ |
2949 | if (is_active & EVENT_TIME) { |
2950 | /* update (and stop) ctx time */ | |
2951 | update_context_time(ctx); | |
2952 | update_cgrp_time_from_cpuctx(cpuctx); | |
2953 | } | |
2954 | ||
8fdc6539 PZ |
2955 | is_active ^= ctx->is_active; /* changed bits */ |
2956 | ||
3cbaa590 | 2957 | if (!ctx->nr_active || !(is_active & EVENT_ALL)) |
facc4307 | 2958 | return; |
5b0311e1 | 2959 | |
fd7d5517 IR |
2960 | /* |
2961 | * If we had been multiplexing, no rotations are necessary, now no events | |
2962 | * are active. | |
2963 | */ | |
2964 | ctx->rotate_necessary = 0; | |
2965 | ||
075e0b00 | 2966 | perf_pmu_disable(ctx->pmu); |
3cbaa590 | 2967 | if (is_active & EVENT_PINNED) { |
6668128a | 2968 | list_for_each_entry_safe(event, tmp, &ctx->pinned_active, active_list) |
889ff015 | 2969 | group_sched_out(event, cpuctx, ctx); |
9ed6060d | 2970 | } |
889ff015 | 2971 | |
3cbaa590 | 2972 | if (is_active & EVENT_FLEXIBLE) { |
6668128a | 2973 | list_for_each_entry_safe(event, tmp, &ctx->flexible_active, active_list) |
8c9ed8e1 | 2974 | group_sched_out(event, cpuctx, ctx); |
9ed6060d | 2975 | } |
1b9a644f | 2976 | perf_pmu_enable(ctx->pmu); |
235c7fc7 IM |
2977 | } |
2978 | ||
564c2b21 | 2979 | /* |
5a3126d4 PZ |
2980 | * Test whether two contexts are equivalent, i.e. whether they have both been |
2981 | * cloned from the same version of the same context. | |
2982 | * | |
2983 | * Equivalence is measured using a generation number in the context that is | |
2984 | * incremented on each modification to it; see unclone_ctx(), list_add_event() | |
2985 | * and list_del_event(). | |
564c2b21 | 2986 | */ |
cdd6c482 IM |
2987 | static int context_equiv(struct perf_event_context *ctx1, |
2988 | struct perf_event_context *ctx2) | |
564c2b21 | 2989 | { |
211de6eb PZ |
2990 | lockdep_assert_held(&ctx1->lock); |
2991 | lockdep_assert_held(&ctx2->lock); | |
2992 | ||
5a3126d4 PZ |
2993 | /* Pinning disables the swap optimization */ |
2994 | if (ctx1->pin_count || ctx2->pin_count) | |
2995 | return 0; | |
2996 | ||
2997 | /* If ctx1 is the parent of ctx2 */ | |
2998 | if (ctx1 == ctx2->parent_ctx && ctx1->generation == ctx2->parent_gen) | |
2999 | return 1; | |
3000 | ||
3001 | /* If ctx2 is the parent of ctx1 */ | |
3002 | if (ctx1->parent_ctx == ctx2 && ctx1->parent_gen == ctx2->generation) | |
3003 | return 1; | |
3004 | ||
3005 | /* | |
3006 | * If ctx1 and ctx2 have the same parent; we flatten the parent | |
3007 | * hierarchy, see perf_event_init_context(). | |
3008 | */ | |
3009 | if (ctx1->parent_ctx && ctx1->parent_ctx == ctx2->parent_ctx && | |
3010 | ctx1->parent_gen == ctx2->parent_gen) | |
3011 | return 1; | |
3012 | ||
3013 | /* Unmatched */ | |
3014 | return 0; | |
564c2b21 PM |
3015 | } |
3016 | ||
cdd6c482 IM |
3017 | static void __perf_event_sync_stat(struct perf_event *event, |
3018 | struct perf_event *next_event) | |
bfbd3381 PZ |
3019 | { |
3020 | u64 value; | |
3021 | ||
cdd6c482 | 3022 | if (!event->attr.inherit_stat) |
bfbd3381 PZ |
3023 | return; |
3024 | ||
3025 | /* | |
cdd6c482 | 3026 | * Update the event value, we cannot use perf_event_read() |
bfbd3381 PZ |
3027 | * because we're in the middle of a context switch and have IRQs |
3028 | * disabled, which upsets smp_call_function_single(), however | |
cdd6c482 | 3029 | * we know the event must be on the current CPU, therefore we |
bfbd3381 PZ |
3030 | * don't need to use it. |
3031 | */ | |
0d3d73aa | 3032 | if (event->state == PERF_EVENT_STATE_ACTIVE) |
3dbebf15 | 3033 | event->pmu->read(event); |
bfbd3381 | 3034 | |
0d3d73aa | 3035 | perf_event_update_time(event); |
bfbd3381 PZ |
3036 | |
3037 | /* | |
cdd6c482 | 3038 | * In order to keep per-task stats reliable we need to flip the event |
bfbd3381 PZ |
3039 | * values when we flip the contexts. |
3040 | */ | |
e7850595 PZ |
3041 | value = local64_read(&next_event->count); |
3042 | value = local64_xchg(&event->count, value); | |
3043 | local64_set(&next_event->count, value); | |
bfbd3381 | 3044 | |
cdd6c482 IM |
3045 | swap(event->total_time_enabled, next_event->total_time_enabled); |
3046 | swap(event->total_time_running, next_event->total_time_running); | |
19d2e755 | 3047 | |
bfbd3381 | 3048 | /* |
19d2e755 | 3049 | * Since we swizzled the values, update the user visible data too. |
bfbd3381 | 3050 | */ |
cdd6c482 IM |
3051 | perf_event_update_userpage(event); |
3052 | perf_event_update_userpage(next_event); | |
bfbd3381 PZ |
3053 | } |
3054 | ||
cdd6c482 IM |
3055 | static void perf_event_sync_stat(struct perf_event_context *ctx, |
3056 | struct perf_event_context *next_ctx) | |
bfbd3381 | 3057 | { |
cdd6c482 | 3058 | struct perf_event *event, *next_event; |
bfbd3381 PZ |
3059 | |
3060 | if (!ctx->nr_stat) | |
3061 | return; | |
3062 | ||
02ffdbc8 PZ |
3063 | update_context_time(ctx); |
3064 | ||
cdd6c482 IM |
3065 | event = list_first_entry(&ctx->event_list, |
3066 | struct perf_event, event_entry); | |
bfbd3381 | 3067 | |
cdd6c482 IM |
3068 | next_event = list_first_entry(&next_ctx->event_list, |
3069 | struct perf_event, event_entry); | |
bfbd3381 | 3070 | |
cdd6c482 IM |
3071 | while (&event->event_entry != &ctx->event_list && |
3072 | &next_event->event_entry != &next_ctx->event_list) { | |
bfbd3381 | 3073 | |
cdd6c482 | 3074 | __perf_event_sync_stat(event, next_event); |
bfbd3381 | 3075 | |
cdd6c482 IM |
3076 | event = list_next_entry(event, event_entry); |
3077 | next_event = list_next_entry(next_event, event_entry); | |
bfbd3381 PZ |
3078 | } |
3079 | } | |
3080 | ||
fe4b04fa PZ |
3081 | static void perf_event_context_sched_out(struct task_struct *task, int ctxn, |
3082 | struct task_struct *next) | |
0793a61d | 3083 | { |
8dc85d54 | 3084 | struct perf_event_context *ctx = task->perf_event_ctxp[ctxn]; |
cdd6c482 | 3085 | struct perf_event_context *next_ctx; |
5a3126d4 | 3086 | struct perf_event_context *parent, *next_parent; |
108b02cf | 3087 | struct perf_cpu_context *cpuctx; |
c93f7669 | 3088 | int do_switch = 1; |
0793a61d | 3089 | |
108b02cf PZ |
3090 | if (likely(!ctx)) |
3091 | return; | |
10989fb2 | 3092 | |
108b02cf PZ |
3093 | cpuctx = __get_cpu_context(ctx); |
3094 | if (!cpuctx->task_ctx) | |
0793a61d TG |
3095 | return; |
3096 | ||
c93f7669 | 3097 | rcu_read_lock(); |
8dc85d54 | 3098 | next_ctx = next->perf_event_ctxp[ctxn]; |
5a3126d4 PZ |
3099 | if (!next_ctx) |
3100 | goto unlock; | |
3101 | ||
3102 | parent = rcu_dereference(ctx->parent_ctx); | |
3103 | next_parent = rcu_dereference(next_ctx->parent_ctx); | |
3104 | ||
3105 | /* If neither context have a parent context; they cannot be clones. */ | |
802c8a61 | 3106 | if (!parent && !next_parent) |
5a3126d4 PZ |
3107 | goto unlock; |
3108 | ||
3109 | if (next_parent == ctx || next_ctx == parent || next_parent == parent) { | |
c93f7669 PM |
3110 | /* |
3111 | * Looks like the two contexts are clones, so we might be | |
3112 | * able to optimize the context switch. We lock both | |
3113 | * contexts and check that they are clones under the | |
3114 | * lock (including re-checking that neither has been | |
3115 | * uncloned in the meantime). It doesn't matter which | |
3116 | * order we take the locks because no other cpu could | |
3117 | * be trying to lock both of these tasks. | |
3118 | */ | |
e625cce1 TG |
3119 | raw_spin_lock(&ctx->lock); |
3120 | raw_spin_lock_nested(&next_ctx->lock, SINGLE_DEPTH_NESTING); | |
c93f7669 | 3121 | if (context_equiv(ctx, next_ctx)) { |
63b6da39 PZ |
3122 | WRITE_ONCE(ctx->task, next); |
3123 | WRITE_ONCE(next_ctx->task, task); | |
5a158c3c YZ |
3124 | |
3125 | swap(ctx->task_ctx_data, next_ctx->task_ctx_data); | |
3126 | ||
63b6da39 PZ |
3127 | /* |
3128 | * RCU_INIT_POINTER here is safe because we've not | |
3129 | * modified the ctx and the above modification of | |
3130 | * ctx->task and ctx->task_ctx_data are immaterial | |
3131 | * since those values are always verified under | |
3132 | * ctx->lock which we're now holding. | |
3133 | */ | |
3134 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], next_ctx); | |
3135 | RCU_INIT_POINTER(next->perf_event_ctxp[ctxn], ctx); | |
3136 | ||
c93f7669 | 3137 | do_switch = 0; |
bfbd3381 | 3138 | |
cdd6c482 | 3139 | perf_event_sync_stat(ctx, next_ctx); |
c93f7669 | 3140 | } |
e625cce1 TG |
3141 | raw_spin_unlock(&next_ctx->lock); |
3142 | raw_spin_unlock(&ctx->lock); | |
564c2b21 | 3143 | } |
5a3126d4 | 3144 | unlock: |
c93f7669 | 3145 | rcu_read_unlock(); |
564c2b21 | 3146 | |
c93f7669 | 3147 | if (do_switch) { |
facc4307 | 3148 | raw_spin_lock(&ctx->lock); |
487f05e1 | 3149 | task_ctx_sched_out(cpuctx, ctx, EVENT_ALL); |
facc4307 | 3150 | raw_spin_unlock(&ctx->lock); |
c93f7669 | 3151 | } |
0793a61d TG |
3152 | } |
3153 | ||
e48c1788 PZ |
3154 | static DEFINE_PER_CPU(struct list_head, sched_cb_list); |
3155 | ||
ba532500 YZ |
3156 | void perf_sched_cb_dec(struct pmu *pmu) |
3157 | { | |
e48c1788 PZ |
3158 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
3159 | ||
ba532500 | 3160 | this_cpu_dec(perf_sched_cb_usages); |
e48c1788 PZ |
3161 | |
3162 | if (!--cpuctx->sched_cb_usage) | |
3163 | list_del(&cpuctx->sched_cb_entry); | |
ba532500 YZ |
3164 | } |
3165 | ||
e48c1788 | 3166 | |
ba532500 YZ |
3167 | void perf_sched_cb_inc(struct pmu *pmu) |
3168 | { | |
e48c1788 PZ |
3169 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
3170 | ||
3171 | if (!cpuctx->sched_cb_usage++) | |
3172 | list_add(&cpuctx->sched_cb_entry, this_cpu_ptr(&sched_cb_list)); | |
3173 | ||
ba532500 YZ |
3174 | this_cpu_inc(perf_sched_cb_usages); |
3175 | } | |
3176 | ||
3177 | /* | |
3178 | * This function provides the context switch callback to the lower code | |
3179 | * layer. It is invoked ONLY when the context switch callback is enabled. | |
09e61b4f PZ |
3180 | * |
3181 | * This callback is relevant even to per-cpu events; for example multi event | |
3182 | * PEBS requires this to provide PID/TID information. This requires we flush | |
3183 | * all queued PEBS records before we context switch to a new task. | |
ba532500 YZ |
3184 | */ |
3185 | static void perf_pmu_sched_task(struct task_struct *prev, | |
3186 | struct task_struct *next, | |
3187 | bool sched_in) | |
3188 | { | |
3189 | struct perf_cpu_context *cpuctx; | |
3190 | struct pmu *pmu; | |
ba532500 YZ |
3191 | |
3192 | if (prev == next) | |
3193 | return; | |
3194 | ||
e48c1788 | 3195 | list_for_each_entry(cpuctx, this_cpu_ptr(&sched_cb_list), sched_cb_entry) { |
1fd7e416 | 3196 | pmu = cpuctx->ctx.pmu; /* software PMUs will not have sched_task */ |
ba532500 | 3197 | |
e48c1788 PZ |
3198 | if (WARN_ON_ONCE(!pmu->sched_task)) |
3199 | continue; | |
ba532500 | 3200 | |
e48c1788 PZ |
3201 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
3202 | perf_pmu_disable(pmu); | |
ba532500 | 3203 | |
e48c1788 | 3204 | pmu->sched_task(cpuctx->task_ctx, sched_in); |
ba532500 | 3205 | |
e48c1788 PZ |
3206 | perf_pmu_enable(pmu); |
3207 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
ba532500 | 3208 | } |
ba532500 YZ |
3209 | } |
3210 | ||
45ac1403 AH |
3211 | static void perf_event_switch(struct task_struct *task, |
3212 | struct task_struct *next_prev, bool sched_in); | |
3213 | ||
8dc85d54 PZ |
3214 | #define for_each_task_context_nr(ctxn) \ |
3215 | for ((ctxn) = 0; (ctxn) < perf_nr_task_contexts; (ctxn)++) | |
3216 | ||
3217 | /* | |
3218 | * Called from scheduler to remove the events of the current task, | |
3219 | * with interrupts disabled. | |
3220 | * | |
3221 | * We stop each event and update the event value in event->count. | |
3222 | * | |
3223 | * This does not protect us against NMI, but disable() | |
3224 | * sets the disabled bit in the control field of event _before_ | |
3225 | * accessing the event control register. If a NMI hits, then it will | |
3226 | * not restart the event. | |
3227 | */ | |
ab0cce56 JO |
3228 | void __perf_event_task_sched_out(struct task_struct *task, |
3229 | struct task_struct *next) | |
8dc85d54 PZ |
3230 | { |
3231 | int ctxn; | |
3232 | ||
ba532500 YZ |
3233 | if (__this_cpu_read(perf_sched_cb_usages)) |
3234 | perf_pmu_sched_task(task, next, false); | |
3235 | ||
45ac1403 AH |
3236 | if (atomic_read(&nr_switch_events)) |
3237 | perf_event_switch(task, next, false); | |
3238 | ||
8dc85d54 PZ |
3239 | for_each_task_context_nr(ctxn) |
3240 | perf_event_context_sched_out(task, ctxn, next); | |
e5d1367f SE |
3241 | |
3242 | /* | |
3243 | * if cgroup events exist on this CPU, then we need | |
3244 | * to check if we have to switch out PMU state. | |
3245 | * cgroup event are system-wide mode only | |
3246 | */ | |
4a32fea9 | 3247 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) |
a8d757ef | 3248 | perf_cgroup_sched_out(task, next); |
8dc85d54 PZ |
3249 | } |
3250 | ||
5b0311e1 FW |
3251 | /* |
3252 | * Called with IRQs disabled | |
3253 | */ | |
3254 | static void cpu_ctx_sched_out(struct perf_cpu_context *cpuctx, | |
3255 | enum event_type_t event_type) | |
3256 | { | |
3257 | ctx_sched_out(&cpuctx->ctx, cpuctx, event_type); | |
04289bb9 IM |
3258 | } |
3259 | ||
1cac7b1a PZ |
3260 | static int visit_groups_merge(struct perf_event_groups *groups, int cpu, |
3261 | int (*func)(struct perf_event *, void *), void *data) | |
0793a61d | 3262 | { |
1cac7b1a PZ |
3263 | struct perf_event **evt, *evt1, *evt2; |
3264 | int ret; | |
8e1a2031 | 3265 | |
1cac7b1a PZ |
3266 | evt1 = perf_event_groups_first(groups, -1); |
3267 | evt2 = perf_event_groups_first(groups, cpu); | |
3268 | ||
3269 | while (evt1 || evt2) { | |
3270 | if (evt1 && evt2) { | |
3271 | if (evt1->group_index < evt2->group_index) | |
3272 | evt = &evt1; | |
3273 | else | |
3274 | evt = &evt2; | |
3275 | } else if (evt1) { | |
3276 | evt = &evt1; | |
3277 | } else { | |
3278 | evt = &evt2; | |
8e1a2031 | 3279 | } |
1cac7b1a PZ |
3280 | |
3281 | ret = func(*evt, data); | |
3282 | if (ret) | |
3283 | return ret; | |
3284 | ||
3285 | *evt = perf_event_groups_next(*evt); | |
8e1a2031 | 3286 | } |
0793a61d | 3287 | |
1cac7b1a PZ |
3288 | return 0; |
3289 | } | |
3290 | ||
3291 | struct sched_in_data { | |
3292 | struct perf_event_context *ctx; | |
3293 | struct perf_cpu_context *cpuctx; | |
3294 | int can_add_hw; | |
3295 | }; | |
3296 | ||
3297 | static int pinned_sched_in(struct perf_event *event, void *data) | |
3298 | { | |
3299 | struct sched_in_data *sid = data; | |
3300 | ||
3301 | if (event->state <= PERF_EVENT_STATE_OFF) | |
3302 | return 0; | |
3303 | ||
3304 | if (!event_filter_match(event)) | |
3305 | return 0; | |
3306 | ||
6668128a PZ |
3307 | if (group_can_go_on(event, sid->cpuctx, sid->can_add_hw)) { |
3308 | if (!group_sched_in(event, sid->cpuctx, sid->ctx)) | |
3309 | list_add_tail(&event->active_list, &sid->ctx->pinned_active); | |
3310 | } | |
1cac7b1a PZ |
3311 | |
3312 | /* | |
3313 | * If this pinned group hasn't been scheduled, | |
3314 | * put it in error state. | |
3315 | */ | |
3316 | if (event->state == PERF_EVENT_STATE_INACTIVE) | |
3317 | perf_event_set_state(event, PERF_EVENT_STATE_ERROR); | |
3318 | ||
3319 | return 0; | |
3320 | } | |
3321 | ||
3322 | static int flexible_sched_in(struct perf_event *event, void *data) | |
3323 | { | |
3324 | struct sched_in_data *sid = data; | |
3325 | ||
3326 | if (event->state <= PERF_EVENT_STATE_OFF) | |
3327 | return 0; | |
3328 | ||
3329 | if (!event_filter_match(event)) | |
3330 | return 0; | |
3331 | ||
3332 | if (group_can_go_on(event, sid->cpuctx, sid->can_add_hw)) { | |
fd7d5517 IR |
3333 | int ret = group_sched_in(event, sid->cpuctx, sid->ctx); |
3334 | if (ret) { | |
1cac7b1a | 3335 | sid->can_add_hw = 0; |
fd7d5517 IR |
3336 | sid->ctx->rotate_necessary = 1; |
3337 | return 0; | |
3338 | } | |
3339 | list_add_tail(&event->active_list, &sid->ctx->flexible_active); | |
3b6f9e5c | 3340 | } |
1cac7b1a PZ |
3341 | |
3342 | return 0; | |
5b0311e1 FW |
3343 | } |
3344 | ||
3345 | static void | |
1cac7b1a PZ |
3346 | ctx_pinned_sched_in(struct perf_event_context *ctx, |
3347 | struct perf_cpu_context *cpuctx) | |
5b0311e1 | 3348 | { |
1cac7b1a PZ |
3349 | struct sched_in_data sid = { |
3350 | .ctx = ctx, | |
3351 | .cpuctx = cpuctx, | |
3352 | .can_add_hw = 1, | |
3353 | }; | |
3b6f9e5c | 3354 | |
1cac7b1a PZ |
3355 | visit_groups_merge(&ctx->pinned_groups, |
3356 | smp_processor_id(), | |
3357 | pinned_sched_in, &sid); | |
3358 | } | |
8e1a2031 | 3359 | |
1cac7b1a PZ |
3360 | static void |
3361 | ctx_flexible_sched_in(struct perf_event_context *ctx, | |
3362 | struct perf_cpu_context *cpuctx) | |
3363 | { | |
3364 | struct sched_in_data sid = { | |
3365 | .ctx = ctx, | |
3366 | .cpuctx = cpuctx, | |
3367 | .can_add_hw = 1, | |
3368 | }; | |
0793a61d | 3369 | |
1cac7b1a PZ |
3370 | visit_groups_merge(&ctx->flexible_groups, |
3371 | smp_processor_id(), | |
3372 | flexible_sched_in, &sid); | |
5b0311e1 FW |
3373 | } |
3374 | ||
3375 | static void | |
3376 | ctx_sched_in(struct perf_event_context *ctx, | |
3377 | struct perf_cpu_context *cpuctx, | |
e5d1367f SE |
3378 | enum event_type_t event_type, |
3379 | struct task_struct *task) | |
5b0311e1 | 3380 | { |
db24d33e | 3381 | int is_active = ctx->is_active; |
c994d613 PZ |
3382 | u64 now; |
3383 | ||
3384 | lockdep_assert_held(&ctx->lock); | |
e5d1367f | 3385 | |
5b0311e1 | 3386 | if (likely(!ctx->nr_events)) |
facc4307 | 3387 | return; |
5b0311e1 | 3388 | |
3cbaa590 | 3389 | ctx->is_active |= (event_type | EVENT_TIME); |
63e30d3e PZ |
3390 | if (ctx->task) { |
3391 | if (!is_active) | |
3392 | cpuctx->task_ctx = ctx; | |
3393 | else | |
3394 | WARN_ON_ONCE(cpuctx->task_ctx != ctx); | |
3395 | } | |
3396 | ||
3cbaa590 PZ |
3397 | is_active ^= ctx->is_active; /* changed bits */ |
3398 | ||
3399 | if (is_active & EVENT_TIME) { | |
3400 | /* start ctx time */ | |
3401 | now = perf_clock(); | |
3402 | ctx->timestamp = now; | |
3403 | perf_cgroup_set_timestamp(task, ctx); | |
3404 | } | |
3405 | ||
5b0311e1 FW |
3406 | /* |
3407 | * First go through the list and put on any pinned groups | |
3408 | * in order to give them the best chance of going on. | |
3409 | */ | |
3cbaa590 | 3410 | if (is_active & EVENT_PINNED) |
6e37738a | 3411 | ctx_pinned_sched_in(ctx, cpuctx); |
5b0311e1 FW |
3412 | |
3413 | /* Then walk through the lower prio flexible groups */ | |
3cbaa590 | 3414 | if (is_active & EVENT_FLEXIBLE) |
6e37738a | 3415 | ctx_flexible_sched_in(ctx, cpuctx); |
235c7fc7 IM |
3416 | } |
3417 | ||
329c0e01 | 3418 | static void cpu_ctx_sched_in(struct perf_cpu_context *cpuctx, |
e5d1367f SE |
3419 | enum event_type_t event_type, |
3420 | struct task_struct *task) | |
329c0e01 FW |
3421 | { |
3422 | struct perf_event_context *ctx = &cpuctx->ctx; | |
3423 | ||
e5d1367f | 3424 | ctx_sched_in(ctx, cpuctx, event_type, task); |
329c0e01 FW |
3425 | } |
3426 | ||
e5d1367f SE |
3427 | static void perf_event_context_sched_in(struct perf_event_context *ctx, |
3428 | struct task_struct *task) | |
235c7fc7 | 3429 | { |
108b02cf | 3430 | struct perf_cpu_context *cpuctx; |
235c7fc7 | 3431 | |
108b02cf | 3432 | cpuctx = __get_cpu_context(ctx); |
329c0e01 FW |
3433 | if (cpuctx->task_ctx == ctx) |
3434 | return; | |
3435 | ||
facc4307 | 3436 | perf_ctx_lock(cpuctx, ctx); |
fdccc3fb | 3437 | /* |
3438 | * We must check ctx->nr_events while holding ctx->lock, such | |
3439 | * that we serialize against perf_install_in_context(). | |
3440 | */ | |
3441 | if (!ctx->nr_events) | |
3442 | goto unlock; | |
3443 | ||
1b9a644f | 3444 | perf_pmu_disable(ctx->pmu); |
329c0e01 FW |
3445 | /* |
3446 | * We want to keep the following priority order: | |
3447 | * cpu pinned (that don't need to move), task pinned, | |
3448 | * cpu flexible, task flexible. | |
fe45bafb AS |
3449 | * |
3450 | * However, if task's ctx is not carrying any pinned | |
3451 | * events, no need to flip the cpuctx's events around. | |
329c0e01 | 3452 | */ |
8e1a2031 | 3453 | if (!RB_EMPTY_ROOT(&ctx->pinned_groups.tree)) |
fe45bafb | 3454 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); |
63e30d3e | 3455 | perf_event_sched_in(cpuctx, ctx, task); |
facc4307 | 3456 | perf_pmu_enable(ctx->pmu); |
fdccc3fb | 3457 | |
3458 | unlock: | |
facc4307 | 3459 | perf_ctx_unlock(cpuctx, ctx); |
235c7fc7 IM |
3460 | } |
3461 | ||
8dc85d54 PZ |
3462 | /* |
3463 | * Called from scheduler to add the events of the current task | |
3464 | * with interrupts disabled. | |
3465 | * | |
3466 | * We restore the event value and then enable it. | |
3467 | * | |
3468 | * This does not protect us against NMI, but enable() | |
3469 | * sets the enabled bit in the control field of event _before_ | |
3470 | * accessing the event control register. If a NMI hits, then it will | |
3471 | * keep the event running. | |
3472 | */ | |
ab0cce56 JO |
3473 | void __perf_event_task_sched_in(struct task_struct *prev, |
3474 | struct task_struct *task) | |
8dc85d54 PZ |
3475 | { |
3476 | struct perf_event_context *ctx; | |
3477 | int ctxn; | |
3478 | ||
7e41d177 PZ |
3479 | /* |
3480 | * If cgroup events exist on this CPU, then we need to check if we have | |
3481 | * to switch in PMU state; cgroup event are system-wide mode only. | |
3482 | * | |
3483 | * Since cgroup events are CPU events, we must schedule these in before | |
3484 | * we schedule in the task events. | |
3485 | */ | |
3486 | if (atomic_read(this_cpu_ptr(&perf_cgroup_events))) | |
3487 | perf_cgroup_sched_in(prev, task); | |
3488 | ||
8dc85d54 PZ |
3489 | for_each_task_context_nr(ctxn) { |
3490 | ctx = task->perf_event_ctxp[ctxn]; | |
3491 | if (likely(!ctx)) | |
3492 | continue; | |
3493 | ||
e5d1367f | 3494 | perf_event_context_sched_in(ctx, task); |
8dc85d54 | 3495 | } |
d010b332 | 3496 | |
45ac1403 AH |
3497 | if (atomic_read(&nr_switch_events)) |
3498 | perf_event_switch(task, prev, true); | |
3499 | ||
ba532500 YZ |
3500 | if (__this_cpu_read(perf_sched_cb_usages)) |
3501 | perf_pmu_sched_task(prev, task, true); | |
235c7fc7 IM |
3502 | } |
3503 | ||
abd50713 PZ |
3504 | static u64 perf_calculate_period(struct perf_event *event, u64 nsec, u64 count) |
3505 | { | |
3506 | u64 frequency = event->attr.sample_freq; | |
3507 | u64 sec = NSEC_PER_SEC; | |
3508 | u64 divisor, dividend; | |
3509 | ||
3510 | int count_fls, nsec_fls, frequency_fls, sec_fls; | |
3511 | ||
3512 | count_fls = fls64(count); | |
3513 | nsec_fls = fls64(nsec); | |
3514 | frequency_fls = fls64(frequency); | |
3515 | sec_fls = 30; | |
3516 | ||
3517 | /* | |
3518 | * We got @count in @nsec, with a target of sample_freq HZ | |
3519 | * the target period becomes: | |
3520 | * | |
3521 | * @count * 10^9 | |
3522 | * period = ------------------- | |
3523 | * @nsec * sample_freq | |
3524 | * | |
3525 | */ | |
3526 | ||
3527 | /* | |
3528 | * Reduce accuracy by one bit such that @a and @b converge | |
3529 | * to a similar magnitude. | |
3530 | */ | |
fe4b04fa | 3531 | #define REDUCE_FLS(a, b) \ |
abd50713 PZ |
3532 | do { \ |
3533 | if (a##_fls > b##_fls) { \ | |
3534 | a >>= 1; \ | |
3535 | a##_fls--; \ | |
3536 | } else { \ | |
3537 | b >>= 1; \ | |
3538 | b##_fls--; \ | |
3539 | } \ | |
3540 | } while (0) | |
3541 | ||
3542 | /* | |
3543 | * Reduce accuracy until either term fits in a u64, then proceed with | |
3544 | * the other, so that finally we can do a u64/u64 division. | |
3545 | */ | |
3546 | while (count_fls + sec_fls > 64 && nsec_fls + frequency_fls > 64) { | |
3547 | REDUCE_FLS(nsec, frequency); | |
3548 | REDUCE_FLS(sec, count); | |
3549 | } | |
3550 | ||
3551 | if (count_fls + sec_fls > 64) { | |
3552 | divisor = nsec * frequency; | |
3553 | ||
3554 | while (count_fls + sec_fls > 64) { | |
3555 | REDUCE_FLS(count, sec); | |
3556 | divisor >>= 1; | |
3557 | } | |
3558 | ||
3559 | dividend = count * sec; | |
3560 | } else { | |
3561 | dividend = count * sec; | |
3562 | ||
3563 | while (nsec_fls + frequency_fls > 64) { | |
3564 | REDUCE_FLS(nsec, frequency); | |
3565 | dividend >>= 1; | |
3566 | } | |
3567 | ||
3568 | divisor = nsec * frequency; | |
3569 | } | |
3570 | ||
f6ab91ad PZ |
3571 | if (!divisor) |
3572 | return dividend; | |
3573 | ||
abd50713 PZ |
3574 | return div64_u64(dividend, divisor); |
3575 | } | |
3576 | ||
e050e3f0 SE |
3577 | static DEFINE_PER_CPU(int, perf_throttled_count); |
3578 | static DEFINE_PER_CPU(u64, perf_throttled_seq); | |
3579 | ||
f39d47ff | 3580 | static void perf_adjust_period(struct perf_event *event, u64 nsec, u64 count, bool disable) |
bd2b5b12 | 3581 | { |
cdd6c482 | 3582 | struct hw_perf_event *hwc = &event->hw; |
f6ab91ad | 3583 | s64 period, sample_period; |
bd2b5b12 PZ |
3584 | s64 delta; |
3585 | ||
abd50713 | 3586 | period = perf_calculate_period(event, nsec, count); |
bd2b5b12 PZ |
3587 | |
3588 | delta = (s64)(period - hwc->sample_period); | |
3589 | delta = (delta + 7) / 8; /* low pass filter */ | |
3590 | ||
3591 | sample_period = hwc->sample_period + delta; | |
3592 | ||
3593 | if (!sample_period) | |
3594 | sample_period = 1; | |
3595 | ||
bd2b5b12 | 3596 | hwc->sample_period = sample_period; |
abd50713 | 3597 | |
e7850595 | 3598 | if (local64_read(&hwc->period_left) > 8*sample_period) { |
f39d47ff SE |
3599 | if (disable) |
3600 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3601 | ||
e7850595 | 3602 | local64_set(&hwc->period_left, 0); |
f39d47ff SE |
3603 | |
3604 | if (disable) | |
3605 | event->pmu->start(event, PERF_EF_RELOAD); | |
abd50713 | 3606 | } |
bd2b5b12 PZ |
3607 | } |
3608 | ||
e050e3f0 SE |
3609 | /* |
3610 | * combine freq adjustment with unthrottling to avoid two passes over the | |
3611 | * events. At the same time, make sure, having freq events does not change | |
3612 | * the rate of unthrottling as that would introduce bias. | |
3613 | */ | |
3614 | static void perf_adjust_freq_unthr_context(struct perf_event_context *ctx, | |
3615 | int needs_unthr) | |
60db5e09 | 3616 | { |
cdd6c482 IM |
3617 | struct perf_event *event; |
3618 | struct hw_perf_event *hwc; | |
e050e3f0 | 3619 | u64 now, period = TICK_NSEC; |
abd50713 | 3620 | s64 delta; |
60db5e09 | 3621 | |
e050e3f0 SE |
3622 | /* |
3623 | * only need to iterate over all events iff: | |
3624 | * - context have events in frequency mode (needs freq adjust) | |
3625 | * - there are events to unthrottle on this cpu | |
3626 | */ | |
3627 | if (!(ctx->nr_freq || needs_unthr)) | |
0f5a2601 PZ |
3628 | return; |
3629 | ||
e050e3f0 | 3630 | raw_spin_lock(&ctx->lock); |
f39d47ff | 3631 | perf_pmu_disable(ctx->pmu); |
e050e3f0 | 3632 | |
03541f8b | 3633 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { |
cdd6c482 | 3634 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
60db5e09 PZ |
3635 | continue; |
3636 | ||
5632ab12 | 3637 | if (!event_filter_match(event)) |
5d27c23d PZ |
3638 | continue; |
3639 | ||
44377277 AS |
3640 | perf_pmu_disable(event->pmu); |
3641 | ||
cdd6c482 | 3642 | hwc = &event->hw; |
6a24ed6c | 3643 | |
ae23bff1 | 3644 | if (hwc->interrupts == MAX_INTERRUPTS) { |
e050e3f0 | 3645 | hwc->interrupts = 0; |
cdd6c482 | 3646 | perf_log_throttle(event, 1); |
a4eaf7f1 | 3647 | event->pmu->start(event, 0); |
a78ac325 PZ |
3648 | } |
3649 | ||
cdd6c482 | 3650 | if (!event->attr.freq || !event->attr.sample_freq) |
44377277 | 3651 | goto next; |
60db5e09 | 3652 | |
e050e3f0 SE |
3653 | /* |
3654 | * stop the event and update event->count | |
3655 | */ | |
3656 | event->pmu->stop(event, PERF_EF_UPDATE); | |
3657 | ||
e7850595 | 3658 | now = local64_read(&event->count); |
abd50713 PZ |
3659 | delta = now - hwc->freq_count_stamp; |
3660 | hwc->freq_count_stamp = now; | |
60db5e09 | 3661 | |
e050e3f0 SE |
3662 | /* |
3663 | * restart the event | |
3664 | * reload only if value has changed | |
f39d47ff SE |
3665 | * we have stopped the event so tell that |
3666 | * to perf_adjust_period() to avoid stopping it | |
3667 | * twice. | |
e050e3f0 | 3668 | */ |
abd50713 | 3669 | if (delta > 0) |
f39d47ff | 3670 | perf_adjust_period(event, period, delta, false); |
e050e3f0 SE |
3671 | |
3672 | event->pmu->start(event, delta > 0 ? PERF_EF_RELOAD : 0); | |
44377277 AS |
3673 | next: |
3674 | perf_pmu_enable(event->pmu); | |
60db5e09 | 3675 | } |
e050e3f0 | 3676 | |
f39d47ff | 3677 | perf_pmu_enable(ctx->pmu); |
e050e3f0 | 3678 | raw_spin_unlock(&ctx->lock); |
60db5e09 PZ |
3679 | } |
3680 | ||
235c7fc7 | 3681 | /* |
8703a7cf | 3682 | * Move @event to the tail of the @ctx's elegible events. |
235c7fc7 | 3683 | */ |
8703a7cf | 3684 | static void rotate_ctx(struct perf_event_context *ctx, struct perf_event *event) |
0793a61d | 3685 | { |
dddd3379 TG |
3686 | /* |
3687 | * Rotate the first entry last of non-pinned groups. Rotation might be | |
3688 | * disabled by the inheritance code. | |
3689 | */ | |
8703a7cf PZ |
3690 | if (ctx->rotate_disable) |
3691 | return; | |
8e1a2031 | 3692 | |
8703a7cf PZ |
3693 | perf_event_groups_delete(&ctx->flexible_groups, event); |
3694 | perf_event_groups_insert(&ctx->flexible_groups, event); | |
235c7fc7 IM |
3695 | } |
3696 | ||
8d5bce0c PZ |
3697 | static inline struct perf_event * |
3698 | ctx_first_active(struct perf_event_context *ctx) | |
235c7fc7 | 3699 | { |
8d5bce0c PZ |
3700 | return list_first_entry_or_null(&ctx->flexible_active, |
3701 | struct perf_event, active_list); | |
3702 | } | |
3703 | ||
3704 | static bool perf_rotate_context(struct perf_cpu_context *cpuctx) | |
3705 | { | |
3706 | struct perf_event *cpu_event = NULL, *task_event = NULL; | |
fd7d5517 IR |
3707 | struct perf_event_context *task_ctx = NULL; |
3708 | int cpu_rotate, task_rotate; | |
8d5bce0c PZ |
3709 | |
3710 | /* | |
3711 | * Since we run this from IRQ context, nobody can install new | |
3712 | * events, thus the event count values are stable. | |
3713 | */ | |
7fc23a53 | 3714 | |
fd7d5517 IR |
3715 | cpu_rotate = cpuctx->ctx.rotate_necessary; |
3716 | task_ctx = cpuctx->task_ctx; | |
3717 | task_rotate = task_ctx ? task_ctx->rotate_necessary : 0; | |
9717e6cd | 3718 | |
8d5bce0c PZ |
3719 | if (!(cpu_rotate || task_rotate)) |
3720 | return false; | |
0f5a2601 | 3721 | |
facc4307 | 3722 | perf_ctx_lock(cpuctx, cpuctx->task_ctx); |
1b9a644f | 3723 | perf_pmu_disable(cpuctx->ctx.pmu); |
60db5e09 | 3724 | |
8d5bce0c | 3725 | if (task_rotate) |
fd7d5517 | 3726 | task_event = ctx_first_active(task_ctx); |
8d5bce0c PZ |
3727 | if (cpu_rotate) |
3728 | cpu_event = ctx_first_active(&cpuctx->ctx); | |
8703a7cf | 3729 | |
8d5bce0c PZ |
3730 | /* |
3731 | * As per the order given at ctx_resched() first 'pop' task flexible | |
3732 | * and then, if needed CPU flexible. | |
3733 | */ | |
fd7d5517 IR |
3734 | if (task_event || (task_ctx && cpu_event)) |
3735 | ctx_sched_out(task_ctx, cpuctx, EVENT_FLEXIBLE); | |
8d5bce0c PZ |
3736 | if (cpu_event) |
3737 | cpu_ctx_sched_out(cpuctx, EVENT_FLEXIBLE); | |
0793a61d | 3738 | |
8d5bce0c | 3739 | if (task_event) |
fd7d5517 | 3740 | rotate_ctx(task_ctx, task_event); |
8d5bce0c PZ |
3741 | if (cpu_event) |
3742 | rotate_ctx(&cpuctx->ctx, cpu_event); | |
235c7fc7 | 3743 | |
fd7d5517 | 3744 | perf_event_sched_in(cpuctx, task_ctx, current); |
235c7fc7 | 3745 | |
0f5a2601 PZ |
3746 | perf_pmu_enable(cpuctx->ctx.pmu); |
3747 | perf_ctx_unlock(cpuctx, cpuctx->task_ctx); | |
9e630205 | 3748 | |
8d5bce0c | 3749 | return true; |
e9d2b064 PZ |
3750 | } |
3751 | ||
3752 | void perf_event_task_tick(void) | |
3753 | { | |
2fde4f94 MR |
3754 | struct list_head *head = this_cpu_ptr(&active_ctx_list); |
3755 | struct perf_event_context *ctx, *tmp; | |
e050e3f0 | 3756 | int throttled; |
b5ab4cd5 | 3757 | |
16444645 | 3758 | lockdep_assert_irqs_disabled(); |
e9d2b064 | 3759 | |
e050e3f0 SE |
3760 | __this_cpu_inc(perf_throttled_seq); |
3761 | throttled = __this_cpu_xchg(perf_throttled_count, 0); | |
555e0c1e | 3762 | tick_dep_clear_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
e050e3f0 | 3763 | |
2fde4f94 | 3764 | list_for_each_entry_safe(ctx, tmp, head, active_ctx_list) |
e050e3f0 | 3765 | perf_adjust_freq_unthr_context(ctx, throttled); |
0793a61d TG |
3766 | } |
3767 | ||
889ff015 FW |
3768 | static int event_enable_on_exec(struct perf_event *event, |
3769 | struct perf_event_context *ctx) | |
3770 | { | |
3771 | if (!event->attr.enable_on_exec) | |
3772 | return 0; | |
3773 | ||
3774 | event->attr.enable_on_exec = 0; | |
3775 | if (event->state >= PERF_EVENT_STATE_INACTIVE) | |
3776 | return 0; | |
3777 | ||
0d3d73aa | 3778 | perf_event_set_state(event, PERF_EVENT_STATE_INACTIVE); |
889ff015 FW |
3779 | |
3780 | return 1; | |
3781 | } | |
3782 | ||
57e7986e | 3783 | /* |
cdd6c482 | 3784 | * Enable all of a task's events that have been marked enable-on-exec. |
57e7986e PM |
3785 | * This expects task == current. |
3786 | */ | |
c1274499 | 3787 | static void perf_event_enable_on_exec(int ctxn) |
57e7986e | 3788 | { |
c1274499 | 3789 | struct perf_event_context *ctx, *clone_ctx = NULL; |
487f05e1 | 3790 | enum event_type_t event_type = 0; |
3e349507 | 3791 | struct perf_cpu_context *cpuctx; |
cdd6c482 | 3792 | struct perf_event *event; |
57e7986e PM |
3793 | unsigned long flags; |
3794 | int enabled = 0; | |
3795 | ||
3796 | local_irq_save(flags); | |
c1274499 | 3797 | ctx = current->perf_event_ctxp[ctxn]; |
cdd6c482 | 3798 | if (!ctx || !ctx->nr_events) |
57e7986e PM |
3799 | goto out; |
3800 | ||
3e349507 PZ |
3801 | cpuctx = __get_cpu_context(ctx); |
3802 | perf_ctx_lock(cpuctx, ctx); | |
7fce2509 | 3803 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
487f05e1 | 3804 | list_for_each_entry(event, &ctx->event_list, event_entry) { |
3e349507 | 3805 | enabled |= event_enable_on_exec(event, ctx); |
487f05e1 AS |
3806 | event_type |= get_event_type(event); |
3807 | } | |
57e7986e PM |
3808 | |
3809 | /* | |
3e349507 | 3810 | * Unclone and reschedule this context if we enabled any event. |
57e7986e | 3811 | */ |
3e349507 | 3812 | if (enabled) { |
211de6eb | 3813 | clone_ctx = unclone_ctx(ctx); |
487f05e1 | 3814 | ctx_resched(cpuctx, ctx, event_type); |
7bbba0eb PZ |
3815 | } else { |
3816 | ctx_sched_in(ctx, cpuctx, EVENT_TIME, current); | |
3e349507 PZ |
3817 | } |
3818 | perf_ctx_unlock(cpuctx, ctx); | |
57e7986e | 3819 | |
9ed6060d | 3820 | out: |
57e7986e | 3821 | local_irq_restore(flags); |
211de6eb PZ |
3822 | |
3823 | if (clone_ctx) | |
3824 | put_ctx(clone_ctx); | |
57e7986e PM |
3825 | } |
3826 | ||
0492d4c5 PZ |
3827 | struct perf_read_data { |
3828 | struct perf_event *event; | |
3829 | bool group; | |
7d88962e | 3830 | int ret; |
0492d4c5 PZ |
3831 | }; |
3832 | ||
451d24d1 | 3833 | static int __perf_event_read_cpu(struct perf_event *event, int event_cpu) |
d6a2f903 | 3834 | { |
d6a2f903 DCC |
3835 | u16 local_pkg, event_pkg; |
3836 | ||
3837 | if (event->group_caps & PERF_EV_CAP_READ_ACTIVE_PKG) { | |
451d24d1 PZ |
3838 | int local_cpu = smp_processor_id(); |
3839 | ||
3840 | event_pkg = topology_physical_package_id(event_cpu); | |
3841 | local_pkg = topology_physical_package_id(local_cpu); | |
d6a2f903 DCC |
3842 | |
3843 | if (event_pkg == local_pkg) | |
3844 | return local_cpu; | |
3845 | } | |
3846 | ||
3847 | return event_cpu; | |
3848 | } | |
3849 | ||
0793a61d | 3850 | /* |
cdd6c482 | 3851 | * Cross CPU call to read the hardware event |
0793a61d | 3852 | */ |
cdd6c482 | 3853 | static void __perf_event_read(void *info) |
0793a61d | 3854 | { |
0492d4c5 PZ |
3855 | struct perf_read_data *data = info; |
3856 | struct perf_event *sub, *event = data->event; | |
cdd6c482 | 3857 | struct perf_event_context *ctx = event->ctx; |
108b02cf | 3858 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
4a00c16e | 3859 | struct pmu *pmu = event->pmu; |
621a01ea | 3860 | |
e1ac3614 PM |
3861 | /* |
3862 | * If this is a task context, we need to check whether it is | |
3863 | * the current task context of this cpu. If not it has been | |
3864 | * scheduled out before the smp call arrived. In that case | |
cdd6c482 IM |
3865 | * event->count would have been updated to a recent sample |
3866 | * when the event was scheduled out. | |
e1ac3614 PM |
3867 | */ |
3868 | if (ctx->task && cpuctx->task_ctx != ctx) | |
3869 | return; | |
3870 | ||
e625cce1 | 3871 | raw_spin_lock(&ctx->lock); |
0c1cbc18 | 3872 | if (ctx->is_active & EVENT_TIME) { |
542e72fc | 3873 | update_context_time(ctx); |
e5d1367f SE |
3874 | update_cgrp_time_from_event(event); |
3875 | } | |
0492d4c5 | 3876 | |
0d3d73aa PZ |
3877 | perf_event_update_time(event); |
3878 | if (data->group) | |
3879 | perf_event_update_sibling_time(event); | |
0c1cbc18 | 3880 | |
4a00c16e SB |
3881 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
3882 | goto unlock; | |
0492d4c5 | 3883 | |
4a00c16e SB |
3884 | if (!data->group) { |
3885 | pmu->read(event); | |
3886 | data->ret = 0; | |
0492d4c5 | 3887 | goto unlock; |
4a00c16e SB |
3888 | } |
3889 | ||
3890 | pmu->start_txn(pmu, PERF_PMU_TXN_READ); | |
3891 | ||
3892 | pmu->read(event); | |
0492d4c5 | 3893 | |
edb39592 | 3894 | for_each_sibling_event(sub, event) { |
4a00c16e SB |
3895 | if (sub->state == PERF_EVENT_STATE_ACTIVE) { |
3896 | /* | |
3897 | * Use sibling's PMU rather than @event's since | |
3898 | * sibling could be on different (eg: software) PMU. | |
3899 | */ | |
0492d4c5 | 3900 | sub->pmu->read(sub); |
4a00c16e | 3901 | } |
0492d4c5 | 3902 | } |
4a00c16e SB |
3903 | |
3904 | data->ret = pmu->commit_txn(pmu); | |
0492d4c5 PZ |
3905 | |
3906 | unlock: | |
e625cce1 | 3907 | raw_spin_unlock(&ctx->lock); |
0793a61d TG |
3908 | } |
3909 | ||
b5e58793 PZ |
3910 | static inline u64 perf_event_count(struct perf_event *event) |
3911 | { | |
c39a0e2c | 3912 | return local64_read(&event->count) + atomic64_read(&event->child_count); |
b5e58793 PZ |
3913 | } |
3914 | ||
ffe8690c KX |
3915 | /* |
3916 | * NMI-safe method to read a local event, that is an event that | |
3917 | * is: | |
3918 | * - either for the current task, or for this CPU | |
3919 | * - does not have inherit set, for inherited task events | |
3920 | * will not be local and we cannot read them atomically | |
3921 | * - must not have a pmu::count method | |
3922 | */ | |
7d9285e8 YS |
3923 | int perf_event_read_local(struct perf_event *event, u64 *value, |
3924 | u64 *enabled, u64 *running) | |
ffe8690c KX |
3925 | { |
3926 | unsigned long flags; | |
f91840a3 | 3927 | int ret = 0; |
ffe8690c KX |
3928 | |
3929 | /* | |
3930 | * Disabling interrupts avoids all counter scheduling (context | |
3931 | * switches, timer based rotation and IPIs). | |
3932 | */ | |
3933 | local_irq_save(flags); | |
3934 | ||
ffe8690c KX |
3935 | /* |
3936 | * It must not be an event with inherit set, we cannot read | |
3937 | * all child counters from atomic context. | |
3938 | */ | |
f91840a3 AS |
3939 | if (event->attr.inherit) { |
3940 | ret = -EOPNOTSUPP; | |
3941 | goto out; | |
3942 | } | |
ffe8690c | 3943 | |
f91840a3 AS |
3944 | /* If this is a per-task event, it must be for current */ |
3945 | if ((event->attach_state & PERF_ATTACH_TASK) && | |
3946 | event->hw.target != current) { | |
3947 | ret = -EINVAL; | |
3948 | goto out; | |
3949 | } | |
3950 | ||
3951 | /* If this is a per-CPU event, it must be for this CPU */ | |
3952 | if (!(event->attach_state & PERF_ATTACH_TASK) && | |
3953 | event->cpu != smp_processor_id()) { | |
3954 | ret = -EINVAL; | |
3955 | goto out; | |
3956 | } | |
ffe8690c | 3957 | |
befb1b3c RC |
3958 | /* If this is a pinned event it must be running on this CPU */ |
3959 | if (event->attr.pinned && event->oncpu != smp_processor_id()) { | |
3960 | ret = -EBUSY; | |
3961 | goto out; | |
3962 | } | |
3963 | ||
ffe8690c KX |
3964 | /* |
3965 | * If the event is currently on this CPU, its either a per-task event, | |
3966 | * or local to this CPU. Furthermore it means its ACTIVE (otherwise | |
3967 | * oncpu == -1). | |
3968 | */ | |
3969 | if (event->oncpu == smp_processor_id()) | |
3970 | event->pmu->read(event); | |
3971 | ||
f91840a3 | 3972 | *value = local64_read(&event->count); |
0d3d73aa PZ |
3973 | if (enabled || running) { |
3974 | u64 now = event->shadow_ctx_time + perf_clock(); | |
3975 | u64 __enabled, __running; | |
3976 | ||
3977 | __perf_update_times(event, now, &__enabled, &__running); | |
3978 | if (enabled) | |
3979 | *enabled = __enabled; | |
3980 | if (running) | |
3981 | *running = __running; | |
3982 | } | |
f91840a3 | 3983 | out: |
ffe8690c KX |
3984 | local_irq_restore(flags); |
3985 | ||
f91840a3 | 3986 | return ret; |
ffe8690c KX |
3987 | } |
3988 | ||
7d88962e | 3989 | static int perf_event_read(struct perf_event *event, bool group) |
0793a61d | 3990 | { |
0c1cbc18 | 3991 | enum perf_event_state state = READ_ONCE(event->state); |
451d24d1 | 3992 | int event_cpu, ret = 0; |
7d88962e | 3993 | |
0793a61d | 3994 | /* |
cdd6c482 IM |
3995 | * If event is enabled and currently active on a CPU, update the |
3996 | * value in the event structure: | |
0793a61d | 3997 | */ |
0c1cbc18 PZ |
3998 | again: |
3999 | if (state == PERF_EVENT_STATE_ACTIVE) { | |
4000 | struct perf_read_data data; | |
4001 | ||
4002 | /* | |
4003 | * Orders the ->state and ->oncpu loads such that if we see | |
4004 | * ACTIVE we must also see the right ->oncpu. | |
4005 | * | |
4006 | * Matches the smp_wmb() from event_sched_in(). | |
4007 | */ | |
4008 | smp_rmb(); | |
d6a2f903 | 4009 | |
451d24d1 PZ |
4010 | event_cpu = READ_ONCE(event->oncpu); |
4011 | if ((unsigned)event_cpu >= nr_cpu_ids) | |
4012 | return 0; | |
4013 | ||
0c1cbc18 PZ |
4014 | data = (struct perf_read_data){ |
4015 | .event = event, | |
4016 | .group = group, | |
4017 | .ret = 0, | |
4018 | }; | |
4019 | ||
451d24d1 PZ |
4020 | preempt_disable(); |
4021 | event_cpu = __perf_event_read_cpu(event, event_cpu); | |
d6a2f903 | 4022 | |
58763148 PZ |
4023 | /* |
4024 | * Purposely ignore the smp_call_function_single() return | |
4025 | * value. | |
4026 | * | |
451d24d1 | 4027 | * If event_cpu isn't a valid CPU it means the event got |
58763148 PZ |
4028 | * scheduled out and that will have updated the event count. |
4029 | * | |
4030 | * Therefore, either way, we'll have an up-to-date event count | |
4031 | * after this. | |
4032 | */ | |
451d24d1 PZ |
4033 | (void)smp_call_function_single(event_cpu, __perf_event_read, &data, 1); |
4034 | preempt_enable(); | |
58763148 | 4035 | ret = data.ret; |
0c1cbc18 PZ |
4036 | |
4037 | } else if (state == PERF_EVENT_STATE_INACTIVE) { | |
2b8988c9 PZ |
4038 | struct perf_event_context *ctx = event->ctx; |
4039 | unsigned long flags; | |
4040 | ||
e625cce1 | 4041 | raw_spin_lock_irqsave(&ctx->lock, flags); |
0c1cbc18 PZ |
4042 | state = event->state; |
4043 | if (state != PERF_EVENT_STATE_INACTIVE) { | |
4044 | raw_spin_unlock_irqrestore(&ctx->lock, flags); | |
4045 | goto again; | |
4046 | } | |
4047 | ||
c530ccd9 | 4048 | /* |
0c1cbc18 PZ |
4049 | * May read while context is not active (e.g., thread is |
4050 | * blocked), in that case we cannot update context time | |
c530ccd9 | 4051 | */ |
0c1cbc18 | 4052 | if (ctx->is_active & EVENT_TIME) { |
c530ccd9 | 4053 | update_context_time(ctx); |
e5d1367f SE |
4054 | update_cgrp_time_from_event(event); |
4055 | } | |
0c1cbc18 | 4056 | |
0d3d73aa | 4057 | perf_event_update_time(event); |
0492d4c5 | 4058 | if (group) |
0d3d73aa | 4059 | perf_event_update_sibling_time(event); |
e625cce1 | 4060 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
0793a61d | 4061 | } |
7d88962e SB |
4062 | |
4063 | return ret; | |
0793a61d TG |
4064 | } |
4065 | ||
a63eaf34 | 4066 | /* |
cdd6c482 | 4067 | * Initialize the perf_event context in a task_struct: |
a63eaf34 | 4068 | */ |
eb184479 | 4069 | static void __perf_event_init_context(struct perf_event_context *ctx) |
a63eaf34 | 4070 | { |
e625cce1 | 4071 | raw_spin_lock_init(&ctx->lock); |
a63eaf34 | 4072 | mutex_init(&ctx->mutex); |
2fde4f94 | 4073 | INIT_LIST_HEAD(&ctx->active_ctx_list); |
8e1a2031 AB |
4074 | perf_event_groups_init(&ctx->pinned_groups); |
4075 | perf_event_groups_init(&ctx->flexible_groups); | |
a63eaf34 | 4076 | INIT_LIST_HEAD(&ctx->event_list); |
6668128a PZ |
4077 | INIT_LIST_HEAD(&ctx->pinned_active); |
4078 | INIT_LIST_HEAD(&ctx->flexible_active); | |
8c94abbb | 4079 | refcount_set(&ctx->refcount, 1); |
eb184479 PZ |
4080 | } |
4081 | ||
4082 | static struct perf_event_context * | |
4083 | alloc_perf_context(struct pmu *pmu, struct task_struct *task) | |
4084 | { | |
4085 | struct perf_event_context *ctx; | |
4086 | ||
4087 | ctx = kzalloc(sizeof(struct perf_event_context), GFP_KERNEL); | |
4088 | if (!ctx) | |
4089 | return NULL; | |
4090 | ||
4091 | __perf_event_init_context(ctx); | |
4092 | if (task) { | |
4093 | ctx->task = task; | |
4094 | get_task_struct(task); | |
0793a61d | 4095 | } |
eb184479 PZ |
4096 | ctx->pmu = pmu; |
4097 | ||
4098 | return ctx; | |
a63eaf34 PM |
4099 | } |
4100 | ||
2ebd4ffb MH |
4101 | static struct task_struct * |
4102 | find_lively_task_by_vpid(pid_t vpid) | |
4103 | { | |
4104 | struct task_struct *task; | |
0793a61d TG |
4105 | |
4106 | rcu_read_lock(); | |
2ebd4ffb | 4107 | if (!vpid) |
0793a61d TG |
4108 | task = current; |
4109 | else | |
2ebd4ffb | 4110 | task = find_task_by_vpid(vpid); |
0793a61d TG |
4111 | if (task) |
4112 | get_task_struct(task); | |
4113 | rcu_read_unlock(); | |
4114 | ||
4115 | if (!task) | |
4116 | return ERR_PTR(-ESRCH); | |
4117 | ||
2ebd4ffb | 4118 | return task; |
2ebd4ffb MH |
4119 | } |
4120 | ||
fe4b04fa PZ |
4121 | /* |
4122 | * Returns a matching context with refcount and pincount. | |
4123 | */ | |
108b02cf | 4124 | static struct perf_event_context * |
4af57ef2 YZ |
4125 | find_get_context(struct pmu *pmu, struct task_struct *task, |
4126 | struct perf_event *event) | |
0793a61d | 4127 | { |
211de6eb | 4128 | struct perf_event_context *ctx, *clone_ctx = NULL; |
22a4f650 | 4129 | struct perf_cpu_context *cpuctx; |
4af57ef2 | 4130 | void *task_ctx_data = NULL; |
25346b93 | 4131 | unsigned long flags; |
8dc85d54 | 4132 | int ctxn, err; |
4af57ef2 | 4133 | int cpu = event->cpu; |
0793a61d | 4134 | |
22a4ec72 | 4135 | if (!task) { |
cdd6c482 | 4136 | /* Must be root to operate on a CPU event: */ |
0764771d | 4137 | if (perf_paranoid_cpu() && !capable(CAP_SYS_ADMIN)) |
0793a61d TG |
4138 | return ERR_PTR(-EACCES); |
4139 | ||
108b02cf | 4140 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); |
0793a61d | 4141 | ctx = &cpuctx->ctx; |
c93f7669 | 4142 | get_ctx(ctx); |
fe4b04fa | 4143 | ++ctx->pin_count; |
0793a61d | 4144 | |
0793a61d TG |
4145 | return ctx; |
4146 | } | |
4147 | ||
8dc85d54 PZ |
4148 | err = -EINVAL; |
4149 | ctxn = pmu->task_ctx_nr; | |
4150 | if (ctxn < 0) | |
4151 | goto errout; | |
4152 | ||
4af57ef2 YZ |
4153 | if (event->attach_state & PERF_ATTACH_TASK_DATA) { |
4154 | task_ctx_data = kzalloc(pmu->task_ctx_size, GFP_KERNEL); | |
4155 | if (!task_ctx_data) { | |
4156 | err = -ENOMEM; | |
4157 | goto errout; | |
4158 | } | |
4159 | } | |
4160 | ||
9ed6060d | 4161 | retry: |
8dc85d54 | 4162 | ctx = perf_lock_task_context(task, ctxn, &flags); |
c93f7669 | 4163 | if (ctx) { |
211de6eb | 4164 | clone_ctx = unclone_ctx(ctx); |
fe4b04fa | 4165 | ++ctx->pin_count; |
4af57ef2 YZ |
4166 | |
4167 | if (task_ctx_data && !ctx->task_ctx_data) { | |
4168 | ctx->task_ctx_data = task_ctx_data; | |
4169 | task_ctx_data = NULL; | |
4170 | } | |
e625cce1 | 4171 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
211de6eb PZ |
4172 | |
4173 | if (clone_ctx) | |
4174 | put_ctx(clone_ctx); | |
9137fb28 | 4175 | } else { |
eb184479 | 4176 | ctx = alloc_perf_context(pmu, task); |
c93f7669 PM |
4177 | err = -ENOMEM; |
4178 | if (!ctx) | |
4179 | goto errout; | |
eb184479 | 4180 | |
4af57ef2 YZ |
4181 | if (task_ctx_data) { |
4182 | ctx->task_ctx_data = task_ctx_data; | |
4183 | task_ctx_data = NULL; | |
4184 | } | |
4185 | ||
dbe08d82 ON |
4186 | err = 0; |
4187 | mutex_lock(&task->perf_event_mutex); | |
4188 | /* | |
4189 | * If it has already passed perf_event_exit_task(). | |
4190 | * we must see PF_EXITING, it takes this mutex too. | |
4191 | */ | |
4192 | if (task->flags & PF_EXITING) | |
4193 | err = -ESRCH; | |
4194 | else if (task->perf_event_ctxp[ctxn]) | |
4195 | err = -EAGAIN; | |
fe4b04fa | 4196 | else { |
9137fb28 | 4197 | get_ctx(ctx); |
fe4b04fa | 4198 | ++ctx->pin_count; |
dbe08d82 | 4199 | rcu_assign_pointer(task->perf_event_ctxp[ctxn], ctx); |
fe4b04fa | 4200 | } |
dbe08d82 ON |
4201 | mutex_unlock(&task->perf_event_mutex); |
4202 | ||
4203 | if (unlikely(err)) { | |
9137fb28 | 4204 | put_ctx(ctx); |
dbe08d82 ON |
4205 | |
4206 | if (err == -EAGAIN) | |
4207 | goto retry; | |
4208 | goto errout; | |
a63eaf34 PM |
4209 | } |
4210 | } | |
4211 | ||
4af57ef2 | 4212 | kfree(task_ctx_data); |
0793a61d | 4213 | return ctx; |
c93f7669 | 4214 | |
9ed6060d | 4215 | errout: |
4af57ef2 | 4216 | kfree(task_ctx_data); |
c93f7669 | 4217 | return ERR_PTR(err); |
0793a61d TG |
4218 | } |
4219 | ||
6fb2915d | 4220 | static void perf_event_free_filter(struct perf_event *event); |
2541517c | 4221 | static void perf_event_free_bpf_prog(struct perf_event *event); |
6fb2915d | 4222 | |
cdd6c482 | 4223 | static void free_event_rcu(struct rcu_head *head) |
592903cd | 4224 | { |
cdd6c482 | 4225 | struct perf_event *event; |
592903cd | 4226 | |
cdd6c482 IM |
4227 | event = container_of(head, struct perf_event, rcu_head); |
4228 | if (event->ns) | |
4229 | put_pid_ns(event->ns); | |
6fb2915d | 4230 | perf_event_free_filter(event); |
cdd6c482 | 4231 | kfree(event); |
592903cd PZ |
4232 | } |
4233 | ||
b69cf536 PZ |
4234 | static void ring_buffer_attach(struct perf_event *event, |
4235 | struct ring_buffer *rb); | |
925d519a | 4236 | |
f2fb6bef KL |
4237 | static void detach_sb_event(struct perf_event *event) |
4238 | { | |
4239 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
4240 | ||
4241 | raw_spin_lock(&pel->lock); | |
4242 | list_del_rcu(&event->sb_list); | |
4243 | raw_spin_unlock(&pel->lock); | |
4244 | } | |
4245 | ||
a4f144eb | 4246 | static bool is_sb_event(struct perf_event *event) |
f2fb6bef | 4247 | { |
a4f144eb DCC |
4248 | struct perf_event_attr *attr = &event->attr; |
4249 | ||
f2fb6bef | 4250 | if (event->parent) |
a4f144eb | 4251 | return false; |
f2fb6bef KL |
4252 | |
4253 | if (event->attach_state & PERF_ATTACH_TASK) | |
a4f144eb | 4254 | return false; |
f2fb6bef | 4255 | |
a4f144eb DCC |
4256 | if (attr->mmap || attr->mmap_data || attr->mmap2 || |
4257 | attr->comm || attr->comm_exec || | |
76193a94 | 4258 | attr->task || attr->ksymbol || |
21038f2b SL |
4259 | attr->context_switch || |
4260 | attr->bpf_event) | |
a4f144eb DCC |
4261 | return true; |
4262 | return false; | |
4263 | } | |
4264 | ||
4265 | static void unaccount_pmu_sb_event(struct perf_event *event) | |
4266 | { | |
4267 | if (is_sb_event(event)) | |
4268 | detach_sb_event(event); | |
f2fb6bef KL |
4269 | } |
4270 | ||
4beb31f3 | 4271 | static void unaccount_event_cpu(struct perf_event *event, int cpu) |
f1600952 | 4272 | { |
4beb31f3 FW |
4273 | if (event->parent) |
4274 | return; | |
4275 | ||
4beb31f3 FW |
4276 | if (is_cgroup_event(event)) |
4277 | atomic_dec(&per_cpu(perf_cgroup_events, cpu)); | |
4278 | } | |
925d519a | 4279 | |
555e0c1e FW |
4280 | #ifdef CONFIG_NO_HZ_FULL |
4281 | static DEFINE_SPINLOCK(nr_freq_lock); | |
4282 | #endif | |
4283 | ||
4284 | static void unaccount_freq_event_nohz(void) | |
4285 | { | |
4286 | #ifdef CONFIG_NO_HZ_FULL | |
4287 | spin_lock(&nr_freq_lock); | |
4288 | if (atomic_dec_and_test(&nr_freq_events)) | |
4289 | tick_nohz_dep_clear(TICK_DEP_BIT_PERF_EVENTS); | |
4290 | spin_unlock(&nr_freq_lock); | |
4291 | #endif | |
4292 | } | |
4293 | ||
4294 | static void unaccount_freq_event(void) | |
4295 | { | |
4296 | if (tick_nohz_full_enabled()) | |
4297 | unaccount_freq_event_nohz(); | |
4298 | else | |
4299 | atomic_dec(&nr_freq_events); | |
4300 | } | |
4301 | ||
4beb31f3 FW |
4302 | static void unaccount_event(struct perf_event *event) |
4303 | { | |
25432ae9 PZ |
4304 | bool dec = false; |
4305 | ||
4beb31f3 FW |
4306 | if (event->parent) |
4307 | return; | |
4308 | ||
4309 | if (event->attach_state & PERF_ATTACH_TASK) | |
25432ae9 | 4310 | dec = true; |
4beb31f3 FW |
4311 | if (event->attr.mmap || event->attr.mmap_data) |
4312 | atomic_dec(&nr_mmap_events); | |
4313 | if (event->attr.comm) | |
4314 | atomic_dec(&nr_comm_events); | |
e4222673 HB |
4315 | if (event->attr.namespaces) |
4316 | atomic_dec(&nr_namespaces_events); | |
4beb31f3 FW |
4317 | if (event->attr.task) |
4318 | atomic_dec(&nr_task_events); | |
948b26b6 | 4319 | if (event->attr.freq) |
555e0c1e | 4320 | unaccount_freq_event(); |
45ac1403 | 4321 | if (event->attr.context_switch) { |
25432ae9 | 4322 | dec = true; |
45ac1403 AH |
4323 | atomic_dec(&nr_switch_events); |
4324 | } | |
4beb31f3 | 4325 | if (is_cgroup_event(event)) |
25432ae9 | 4326 | dec = true; |
4beb31f3 | 4327 | if (has_branch_stack(event)) |
25432ae9 | 4328 | dec = true; |
76193a94 SL |
4329 | if (event->attr.ksymbol) |
4330 | atomic_dec(&nr_ksymbol_events); | |
6ee52e2a SL |
4331 | if (event->attr.bpf_event) |
4332 | atomic_dec(&nr_bpf_events); | |
25432ae9 | 4333 | |
9107c89e PZ |
4334 | if (dec) { |
4335 | if (!atomic_add_unless(&perf_sched_count, -1, 1)) | |
4336 | schedule_delayed_work(&perf_sched_work, HZ); | |
4337 | } | |
4beb31f3 FW |
4338 | |
4339 | unaccount_event_cpu(event, event->cpu); | |
f2fb6bef KL |
4340 | |
4341 | unaccount_pmu_sb_event(event); | |
4beb31f3 | 4342 | } |
925d519a | 4343 | |
9107c89e PZ |
4344 | static void perf_sched_delayed(struct work_struct *work) |
4345 | { | |
4346 | mutex_lock(&perf_sched_mutex); | |
4347 | if (atomic_dec_and_test(&perf_sched_count)) | |
4348 | static_branch_disable(&perf_sched_events); | |
4349 | mutex_unlock(&perf_sched_mutex); | |
4350 | } | |
4351 | ||
bed5b25a AS |
4352 | /* |
4353 | * The following implement mutual exclusion of events on "exclusive" pmus | |
4354 | * (PERF_PMU_CAP_EXCLUSIVE). Such pmus can only have one event scheduled | |
4355 | * at a time, so we disallow creating events that might conflict, namely: | |
4356 | * | |
4357 | * 1) cpu-wide events in the presence of per-task events, | |
4358 | * 2) per-task events in the presence of cpu-wide events, | |
4359 | * 3) two matching events on the same context. | |
4360 | * | |
4361 | * The former two cases are handled in the allocation path (perf_event_alloc(), | |
a0733e69 | 4362 | * _free_event()), the latter -- before the first perf_install_in_context(). |
bed5b25a AS |
4363 | */ |
4364 | static int exclusive_event_init(struct perf_event *event) | |
4365 | { | |
4366 | struct pmu *pmu = event->pmu; | |
4367 | ||
8a58ddae | 4368 | if (!is_exclusive_pmu(pmu)) |
bed5b25a AS |
4369 | return 0; |
4370 | ||
4371 | /* | |
4372 | * Prevent co-existence of per-task and cpu-wide events on the | |
4373 | * same exclusive pmu. | |
4374 | * | |
4375 | * Negative pmu::exclusive_cnt means there are cpu-wide | |
4376 | * events on this "exclusive" pmu, positive means there are | |
4377 | * per-task events. | |
4378 | * | |
4379 | * Since this is called in perf_event_alloc() path, event::ctx | |
4380 | * doesn't exist yet; it is, however, safe to use PERF_ATTACH_TASK | |
4381 | * to mean "per-task event", because unlike other attach states it | |
4382 | * never gets cleared. | |
4383 | */ | |
4384 | if (event->attach_state & PERF_ATTACH_TASK) { | |
4385 | if (!atomic_inc_unless_negative(&pmu->exclusive_cnt)) | |
4386 | return -EBUSY; | |
4387 | } else { | |
4388 | if (!atomic_dec_unless_positive(&pmu->exclusive_cnt)) | |
4389 | return -EBUSY; | |
4390 | } | |
4391 | ||
4392 | return 0; | |
4393 | } | |
4394 | ||
4395 | static void exclusive_event_destroy(struct perf_event *event) | |
4396 | { | |
4397 | struct pmu *pmu = event->pmu; | |
4398 | ||
8a58ddae | 4399 | if (!is_exclusive_pmu(pmu)) |
bed5b25a AS |
4400 | return; |
4401 | ||
4402 | /* see comment in exclusive_event_init() */ | |
4403 | if (event->attach_state & PERF_ATTACH_TASK) | |
4404 | atomic_dec(&pmu->exclusive_cnt); | |
4405 | else | |
4406 | atomic_inc(&pmu->exclusive_cnt); | |
4407 | } | |
4408 | ||
4409 | static bool exclusive_event_match(struct perf_event *e1, struct perf_event *e2) | |
4410 | { | |
3bf6215a | 4411 | if ((e1->pmu == e2->pmu) && |
bed5b25a AS |
4412 | (e1->cpu == e2->cpu || |
4413 | e1->cpu == -1 || | |
4414 | e2->cpu == -1)) | |
4415 | return true; | |
4416 | return false; | |
4417 | } | |
4418 | ||
bed5b25a AS |
4419 | static bool exclusive_event_installable(struct perf_event *event, |
4420 | struct perf_event_context *ctx) | |
4421 | { | |
4422 | struct perf_event *iter_event; | |
4423 | struct pmu *pmu = event->pmu; | |
4424 | ||
8a58ddae AS |
4425 | lockdep_assert_held(&ctx->mutex); |
4426 | ||
4427 | if (!is_exclusive_pmu(pmu)) | |
bed5b25a AS |
4428 | return true; |
4429 | ||
4430 | list_for_each_entry(iter_event, &ctx->event_list, event_entry) { | |
4431 | if (exclusive_event_match(iter_event, event)) | |
4432 | return false; | |
4433 | } | |
4434 | ||
4435 | return true; | |
4436 | } | |
4437 | ||
375637bc AS |
4438 | static void perf_addr_filters_splice(struct perf_event *event, |
4439 | struct list_head *head); | |
4440 | ||
683ede43 | 4441 | static void _free_event(struct perf_event *event) |
f1600952 | 4442 | { |
e360adbe | 4443 | irq_work_sync(&event->pending); |
925d519a | 4444 | |
4beb31f3 | 4445 | unaccount_event(event); |
9ee318a7 | 4446 | |
76369139 | 4447 | if (event->rb) { |
9bb5d40c PZ |
4448 | /* |
4449 | * Can happen when we close an event with re-directed output. | |
4450 | * | |
4451 | * Since we have a 0 refcount, perf_mmap_close() will skip | |
4452 | * over us; possibly making our ring_buffer_put() the last. | |
4453 | */ | |
4454 | mutex_lock(&event->mmap_mutex); | |
b69cf536 | 4455 | ring_buffer_attach(event, NULL); |
9bb5d40c | 4456 | mutex_unlock(&event->mmap_mutex); |
a4be7c27 PZ |
4457 | } |
4458 | ||
e5d1367f SE |
4459 | if (is_cgroup_event(event)) |
4460 | perf_detach_cgroup(event); | |
4461 | ||
a0733e69 PZ |
4462 | if (!event->parent) { |
4463 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) | |
4464 | put_callchain_buffers(); | |
4465 | } | |
4466 | ||
4467 | perf_event_free_bpf_prog(event); | |
375637bc | 4468 | perf_addr_filters_splice(event, NULL); |
c60f83b8 | 4469 | kfree(event->addr_filter_ranges); |
a0733e69 PZ |
4470 | |
4471 | if (event->destroy) | |
4472 | event->destroy(event); | |
4473 | ||
1cf8dfe8 PZ |
4474 | /* |
4475 | * Must be after ->destroy(), due to uprobe_perf_close() using | |
4476 | * hw.target. | |
4477 | */ | |
621b6d2e PB |
4478 | if (event->hw.target) |
4479 | put_task_struct(event->hw.target); | |
4480 | ||
1cf8dfe8 PZ |
4481 | /* |
4482 | * perf_event_free_task() relies on put_ctx() being 'last', in particular | |
4483 | * all task references must be cleaned up. | |
4484 | */ | |
4485 | if (event->ctx) | |
4486 | put_ctx(event->ctx); | |
4487 | ||
62a92c8f AS |
4488 | exclusive_event_destroy(event); |
4489 | module_put(event->pmu->module); | |
a0733e69 PZ |
4490 | |
4491 | call_rcu(&event->rcu_head, free_event_rcu); | |
f1600952 PZ |
4492 | } |
4493 | ||
683ede43 PZ |
4494 | /* |
4495 | * Used to free events which have a known refcount of 1, such as in error paths | |
4496 | * where the event isn't exposed yet and inherited events. | |
4497 | */ | |
4498 | static void free_event(struct perf_event *event) | |
0793a61d | 4499 | { |
683ede43 PZ |
4500 | if (WARN(atomic_long_cmpxchg(&event->refcount, 1, 0) != 1, |
4501 | "unexpected event refcount: %ld; ptr=%p\n", | |
4502 | atomic_long_read(&event->refcount), event)) { | |
4503 | /* leak to avoid use-after-free */ | |
4504 | return; | |
4505 | } | |
0793a61d | 4506 | |
683ede43 | 4507 | _free_event(event); |
0793a61d TG |
4508 | } |
4509 | ||
a66a3052 | 4510 | /* |
f8697762 | 4511 | * Remove user event from the owner task. |
a66a3052 | 4512 | */ |
f8697762 | 4513 | static void perf_remove_from_owner(struct perf_event *event) |
fb0459d7 | 4514 | { |
8882135b | 4515 | struct task_struct *owner; |
fb0459d7 | 4516 | |
8882135b | 4517 | rcu_read_lock(); |
8882135b | 4518 | /* |
f47c02c0 PZ |
4519 | * Matches the smp_store_release() in perf_event_exit_task(). If we |
4520 | * observe !owner it means the list deletion is complete and we can | |
4521 | * indeed free this event, otherwise we need to serialize on | |
8882135b PZ |
4522 | * owner->perf_event_mutex. |
4523 | */ | |
506458ef | 4524 | owner = READ_ONCE(event->owner); |
8882135b PZ |
4525 | if (owner) { |
4526 | /* | |
4527 | * Since delayed_put_task_struct() also drops the last | |
4528 | * task reference we can safely take a new reference | |
4529 | * while holding the rcu_read_lock(). | |
4530 | */ | |
4531 | get_task_struct(owner); | |
4532 | } | |
4533 | rcu_read_unlock(); | |
4534 | ||
4535 | if (owner) { | |
f63a8daa PZ |
4536 | /* |
4537 | * If we're here through perf_event_exit_task() we're already | |
4538 | * holding ctx->mutex which would be an inversion wrt. the | |
4539 | * normal lock order. | |
4540 | * | |
4541 | * However we can safely take this lock because its the child | |
4542 | * ctx->mutex. | |
4543 | */ | |
4544 | mutex_lock_nested(&owner->perf_event_mutex, SINGLE_DEPTH_NESTING); | |
4545 | ||
8882135b PZ |
4546 | /* |
4547 | * We have to re-check the event->owner field, if it is cleared | |
4548 | * we raced with perf_event_exit_task(), acquiring the mutex | |
4549 | * ensured they're done, and we can proceed with freeing the | |
4550 | * event. | |
4551 | */ | |
f47c02c0 | 4552 | if (event->owner) { |
8882135b | 4553 | list_del_init(&event->owner_entry); |
f47c02c0 PZ |
4554 | smp_store_release(&event->owner, NULL); |
4555 | } | |
8882135b PZ |
4556 | mutex_unlock(&owner->perf_event_mutex); |
4557 | put_task_struct(owner); | |
4558 | } | |
f8697762 JO |
4559 | } |
4560 | ||
f8697762 JO |
4561 | static void put_event(struct perf_event *event) |
4562 | { | |
f8697762 JO |
4563 | if (!atomic_long_dec_and_test(&event->refcount)) |
4564 | return; | |
4565 | ||
c6e5b732 PZ |
4566 | _free_event(event); |
4567 | } | |
4568 | ||
4569 | /* | |
4570 | * Kill an event dead; while event:refcount will preserve the event | |
4571 | * object, it will not preserve its functionality. Once the last 'user' | |
4572 | * gives up the object, we'll destroy the thing. | |
4573 | */ | |
4574 | int perf_event_release_kernel(struct perf_event *event) | |
4575 | { | |
a4f4bb6d | 4576 | struct perf_event_context *ctx = event->ctx; |
c6e5b732 | 4577 | struct perf_event *child, *tmp; |
82d94856 | 4578 | LIST_HEAD(free_list); |
c6e5b732 | 4579 | |
a4f4bb6d PZ |
4580 | /* |
4581 | * If we got here through err_file: fput(event_file); we will not have | |
4582 | * attached to a context yet. | |
4583 | */ | |
4584 | if (!ctx) { | |
4585 | WARN_ON_ONCE(event->attach_state & | |
4586 | (PERF_ATTACH_CONTEXT|PERF_ATTACH_GROUP)); | |
4587 | goto no_ctx; | |
4588 | } | |
4589 | ||
f8697762 JO |
4590 | if (!is_kernel_event(event)) |
4591 | perf_remove_from_owner(event); | |
8882135b | 4592 | |
5fa7c8ec | 4593 | ctx = perf_event_ctx_lock(event); |
a83fe28e | 4594 | WARN_ON_ONCE(ctx->parent_ctx); |
a69b0ca4 | 4595 | perf_remove_from_context(event, DETACH_GROUP); |
683ede43 | 4596 | |
a69b0ca4 | 4597 | raw_spin_lock_irq(&ctx->lock); |
683ede43 | 4598 | /* |
d8a8cfc7 | 4599 | * Mark this event as STATE_DEAD, there is no external reference to it |
a69b0ca4 | 4600 | * anymore. |
683ede43 | 4601 | * |
a69b0ca4 PZ |
4602 | * Anybody acquiring event->child_mutex after the below loop _must_ |
4603 | * also see this, most importantly inherit_event() which will avoid | |
4604 | * placing more children on the list. | |
683ede43 | 4605 | * |
c6e5b732 PZ |
4606 | * Thus this guarantees that we will in fact observe and kill _ALL_ |
4607 | * child events. | |
683ede43 | 4608 | */ |
a69b0ca4 PZ |
4609 | event->state = PERF_EVENT_STATE_DEAD; |
4610 | raw_spin_unlock_irq(&ctx->lock); | |
4611 | ||
4612 | perf_event_ctx_unlock(event, ctx); | |
683ede43 | 4613 | |
c6e5b732 PZ |
4614 | again: |
4615 | mutex_lock(&event->child_mutex); | |
4616 | list_for_each_entry(child, &event->child_list, child_list) { | |
a6fa941d | 4617 | |
c6e5b732 PZ |
4618 | /* |
4619 | * Cannot change, child events are not migrated, see the | |
4620 | * comment with perf_event_ctx_lock_nested(). | |
4621 | */ | |
506458ef | 4622 | ctx = READ_ONCE(child->ctx); |
c6e5b732 PZ |
4623 | /* |
4624 | * Since child_mutex nests inside ctx::mutex, we must jump | |
4625 | * through hoops. We start by grabbing a reference on the ctx. | |
4626 | * | |
4627 | * Since the event cannot get freed while we hold the | |
4628 | * child_mutex, the context must also exist and have a !0 | |
4629 | * reference count. | |
4630 | */ | |
4631 | get_ctx(ctx); | |
4632 | ||
4633 | /* | |
4634 | * Now that we have a ctx ref, we can drop child_mutex, and | |
4635 | * acquire ctx::mutex without fear of it going away. Then we | |
4636 | * can re-acquire child_mutex. | |
4637 | */ | |
4638 | mutex_unlock(&event->child_mutex); | |
4639 | mutex_lock(&ctx->mutex); | |
4640 | mutex_lock(&event->child_mutex); | |
4641 | ||
4642 | /* | |
4643 | * Now that we hold ctx::mutex and child_mutex, revalidate our | |
4644 | * state, if child is still the first entry, it didn't get freed | |
4645 | * and we can continue doing so. | |
4646 | */ | |
4647 | tmp = list_first_entry_or_null(&event->child_list, | |
4648 | struct perf_event, child_list); | |
4649 | if (tmp == child) { | |
4650 | perf_remove_from_context(child, DETACH_GROUP); | |
82d94856 | 4651 | list_move(&child->child_list, &free_list); |
c6e5b732 PZ |
4652 | /* |
4653 | * This matches the refcount bump in inherit_event(); | |
4654 | * this can't be the last reference. | |
4655 | */ | |
4656 | put_event(event); | |
4657 | } | |
4658 | ||
4659 | mutex_unlock(&event->child_mutex); | |
4660 | mutex_unlock(&ctx->mutex); | |
4661 | put_ctx(ctx); | |
4662 | goto again; | |
4663 | } | |
4664 | mutex_unlock(&event->child_mutex); | |
4665 | ||
82d94856 | 4666 | list_for_each_entry_safe(child, tmp, &free_list, child_list) { |
1cf8dfe8 PZ |
4667 | void *var = &child->ctx->refcount; |
4668 | ||
82d94856 PZ |
4669 | list_del(&child->child_list); |
4670 | free_event(child); | |
1cf8dfe8 PZ |
4671 | |
4672 | /* | |
4673 | * Wake any perf_event_free_task() waiting for this event to be | |
4674 | * freed. | |
4675 | */ | |
4676 | smp_mb(); /* pairs with wait_var_event() */ | |
4677 | wake_up_var(var); | |
82d94856 PZ |
4678 | } |
4679 | ||
a4f4bb6d PZ |
4680 | no_ctx: |
4681 | put_event(event); /* Must be the 'last' reference */ | |
683ede43 PZ |
4682 | return 0; |
4683 | } | |
4684 | EXPORT_SYMBOL_GPL(perf_event_release_kernel); | |
4685 | ||
8b10c5e2 PZ |
4686 | /* |
4687 | * Called when the last reference to the file is gone. | |
4688 | */ | |
a6fa941d AV |
4689 | static int perf_release(struct inode *inode, struct file *file) |
4690 | { | |
c6e5b732 | 4691 | perf_event_release_kernel(file->private_data); |
a6fa941d | 4692 | return 0; |
fb0459d7 | 4693 | } |
fb0459d7 | 4694 | |
ca0dd44c | 4695 | static u64 __perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) |
e53c0994 | 4696 | { |
cdd6c482 | 4697 | struct perf_event *child; |
e53c0994 PZ |
4698 | u64 total = 0; |
4699 | ||
59ed446f PZ |
4700 | *enabled = 0; |
4701 | *running = 0; | |
4702 | ||
6f10581a | 4703 | mutex_lock(&event->child_mutex); |
01add3ea | 4704 | |
7d88962e | 4705 | (void)perf_event_read(event, false); |
01add3ea SB |
4706 | total += perf_event_count(event); |
4707 | ||
59ed446f PZ |
4708 | *enabled += event->total_time_enabled + |
4709 | atomic64_read(&event->child_total_time_enabled); | |
4710 | *running += event->total_time_running + | |
4711 | atomic64_read(&event->child_total_time_running); | |
4712 | ||
4713 | list_for_each_entry(child, &event->child_list, child_list) { | |
7d88962e | 4714 | (void)perf_event_read(child, false); |
01add3ea | 4715 | total += perf_event_count(child); |
59ed446f PZ |
4716 | *enabled += child->total_time_enabled; |
4717 | *running += child->total_time_running; | |
4718 | } | |
6f10581a | 4719 | mutex_unlock(&event->child_mutex); |
e53c0994 PZ |
4720 | |
4721 | return total; | |
4722 | } | |
ca0dd44c PZ |
4723 | |
4724 | u64 perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) | |
4725 | { | |
4726 | struct perf_event_context *ctx; | |
4727 | u64 count; | |
4728 | ||
4729 | ctx = perf_event_ctx_lock(event); | |
4730 | count = __perf_event_read_value(event, enabled, running); | |
4731 | perf_event_ctx_unlock(event, ctx); | |
4732 | ||
4733 | return count; | |
4734 | } | |
fb0459d7 | 4735 | EXPORT_SYMBOL_GPL(perf_event_read_value); |
e53c0994 | 4736 | |
7d88962e | 4737 | static int __perf_read_group_add(struct perf_event *leader, |
fa8c2693 | 4738 | u64 read_format, u64 *values) |
3dab77fb | 4739 | { |
2aeb1883 | 4740 | struct perf_event_context *ctx = leader->ctx; |
fa8c2693 | 4741 | struct perf_event *sub; |
2aeb1883 | 4742 | unsigned long flags; |
fa8c2693 | 4743 | int n = 1; /* skip @nr */ |
7d88962e | 4744 | int ret; |
f63a8daa | 4745 | |
7d88962e SB |
4746 | ret = perf_event_read(leader, true); |
4747 | if (ret) | |
4748 | return ret; | |
abf4868b | 4749 | |
a9cd8194 PZ |
4750 | raw_spin_lock_irqsave(&ctx->lock, flags); |
4751 | ||
fa8c2693 PZ |
4752 | /* |
4753 | * Since we co-schedule groups, {enabled,running} times of siblings | |
4754 | * will be identical to those of the leader, so we only publish one | |
4755 | * set. | |
4756 | */ | |
4757 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { | |
4758 | values[n++] += leader->total_time_enabled + | |
4759 | atomic64_read(&leader->child_total_time_enabled); | |
4760 | } | |
3dab77fb | 4761 | |
fa8c2693 PZ |
4762 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { |
4763 | values[n++] += leader->total_time_running + | |
4764 | atomic64_read(&leader->child_total_time_running); | |
4765 | } | |
4766 | ||
4767 | /* | |
4768 | * Write {count,id} tuples for every sibling. | |
4769 | */ | |
4770 | values[n++] += perf_event_count(leader); | |
abf4868b PZ |
4771 | if (read_format & PERF_FORMAT_ID) |
4772 | values[n++] = primary_event_id(leader); | |
3dab77fb | 4773 | |
edb39592 | 4774 | for_each_sibling_event(sub, leader) { |
fa8c2693 PZ |
4775 | values[n++] += perf_event_count(sub); |
4776 | if (read_format & PERF_FORMAT_ID) | |
4777 | values[n++] = primary_event_id(sub); | |
4778 | } | |
7d88962e | 4779 | |
2aeb1883 | 4780 | raw_spin_unlock_irqrestore(&ctx->lock, flags); |
7d88962e | 4781 | return 0; |
fa8c2693 | 4782 | } |
3dab77fb | 4783 | |
fa8c2693 PZ |
4784 | static int perf_read_group(struct perf_event *event, |
4785 | u64 read_format, char __user *buf) | |
4786 | { | |
4787 | struct perf_event *leader = event->group_leader, *child; | |
4788 | struct perf_event_context *ctx = leader->ctx; | |
7d88962e | 4789 | int ret; |
fa8c2693 | 4790 | u64 *values; |
3dab77fb | 4791 | |
fa8c2693 | 4792 | lockdep_assert_held(&ctx->mutex); |
3dab77fb | 4793 | |
fa8c2693 PZ |
4794 | values = kzalloc(event->read_size, GFP_KERNEL); |
4795 | if (!values) | |
4796 | return -ENOMEM; | |
3dab77fb | 4797 | |
fa8c2693 PZ |
4798 | values[0] = 1 + leader->nr_siblings; |
4799 | ||
4800 | /* | |
4801 | * By locking the child_mutex of the leader we effectively | |
4802 | * lock the child list of all siblings.. XXX explain how. | |
4803 | */ | |
4804 | mutex_lock(&leader->child_mutex); | |
abf4868b | 4805 | |
7d88962e SB |
4806 | ret = __perf_read_group_add(leader, read_format, values); |
4807 | if (ret) | |
4808 | goto unlock; | |
4809 | ||
4810 | list_for_each_entry(child, &leader->child_list, child_list) { | |
4811 | ret = __perf_read_group_add(child, read_format, values); | |
4812 | if (ret) | |
4813 | goto unlock; | |
4814 | } | |
abf4868b | 4815 | |
fa8c2693 | 4816 | mutex_unlock(&leader->child_mutex); |
abf4868b | 4817 | |
7d88962e | 4818 | ret = event->read_size; |
fa8c2693 PZ |
4819 | if (copy_to_user(buf, values, event->read_size)) |
4820 | ret = -EFAULT; | |
7d88962e | 4821 | goto out; |
fa8c2693 | 4822 | |
7d88962e SB |
4823 | unlock: |
4824 | mutex_unlock(&leader->child_mutex); | |
4825 | out: | |
fa8c2693 | 4826 | kfree(values); |
abf4868b | 4827 | return ret; |
3dab77fb PZ |
4828 | } |
4829 | ||
b15f495b | 4830 | static int perf_read_one(struct perf_event *event, |
3dab77fb PZ |
4831 | u64 read_format, char __user *buf) |
4832 | { | |
59ed446f | 4833 | u64 enabled, running; |
3dab77fb PZ |
4834 | u64 values[4]; |
4835 | int n = 0; | |
4836 | ||
ca0dd44c | 4837 | values[n++] = __perf_event_read_value(event, &enabled, &running); |
59ed446f PZ |
4838 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) |
4839 | values[n++] = enabled; | |
4840 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
4841 | values[n++] = running; | |
3dab77fb | 4842 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 4843 | values[n++] = primary_event_id(event); |
3dab77fb PZ |
4844 | |
4845 | if (copy_to_user(buf, values, n * sizeof(u64))) | |
4846 | return -EFAULT; | |
4847 | ||
4848 | return n * sizeof(u64); | |
4849 | } | |
4850 | ||
dc633982 JO |
4851 | static bool is_event_hup(struct perf_event *event) |
4852 | { | |
4853 | bool no_children; | |
4854 | ||
a69b0ca4 | 4855 | if (event->state > PERF_EVENT_STATE_EXIT) |
dc633982 JO |
4856 | return false; |
4857 | ||
4858 | mutex_lock(&event->child_mutex); | |
4859 | no_children = list_empty(&event->child_list); | |
4860 | mutex_unlock(&event->child_mutex); | |
4861 | return no_children; | |
4862 | } | |
4863 | ||
0793a61d | 4864 | /* |
cdd6c482 | 4865 | * Read the performance event - simple non blocking version for now |
0793a61d TG |
4866 | */ |
4867 | static ssize_t | |
b15f495b | 4868 | __perf_read(struct perf_event *event, char __user *buf, size_t count) |
0793a61d | 4869 | { |
cdd6c482 | 4870 | u64 read_format = event->attr.read_format; |
3dab77fb | 4871 | int ret; |
0793a61d | 4872 | |
3b6f9e5c | 4873 | /* |
788faab7 | 4874 | * Return end-of-file for a read on an event that is in |
3b6f9e5c PM |
4875 | * error state (i.e. because it was pinned but it couldn't be |
4876 | * scheduled on to the CPU at some point). | |
4877 | */ | |
cdd6c482 | 4878 | if (event->state == PERF_EVENT_STATE_ERROR) |
3b6f9e5c PM |
4879 | return 0; |
4880 | ||
c320c7b7 | 4881 | if (count < event->read_size) |
3dab77fb PZ |
4882 | return -ENOSPC; |
4883 | ||
cdd6c482 | 4884 | WARN_ON_ONCE(event->ctx->parent_ctx); |
3dab77fb | 4885 | if (read_format & PERF_FORMAT_GROUP) |
b15f495b | 4886 | ret = perf_read_group(event, read_format, buf); |
3dab77fb | 4887 | else |
b15f495b | 4888 | ret = perf_read_one(event, read_format, buf); |
0793a61d | 4889 | |
3dab77fb | 4890 | return ret; |
0793a61d TG |
4891 | } |
4892 | ||
0793a61d TG |
4893 | static ssize_t |
4894 | perf_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) | |
4895 | { | |
cdd6c482 | 4896 | struct perf_event *event = file->private_data; |
f63a8daa PZ |
4897 | struct perf_event_context *ctx; |
4898 | int ret; | |
0793a61d | 4899 | |
f63a8daa | 4900 | ctx = perf_event_ctx_lock(event); |
b15f495b | 4901 | ret = __perf_read(event, buf, count); |
f63a8daa PZ |
4902 | perf_event_ctx_unlock(event, ctx); |
4903 | ||
4904 | return ret; | |
0793a61d TG |
4905 | } |
4906 | ||
9dd95748 | 4907 | static __poll_t perf_poll(struct file *file, poll_table *wait) |
0793a61d | 4908 | { |
cdd6c482 | 4909 | struct perf_event *event = file->private_data; |
76369139 | 4910 | struct ring_buffer *rb; |
a9a08845 | 4911 | __poll_t events = EPOLLHUP; |
c7138f37 | 4912 | |
e708d7ad | 4913 | poll_wait(file, &event->waitq, wait); |
179033b3 | 4914 | |
dc633982 | 4915 | if (is_event_hup(event)) |
179033b3 | 4916 | return events; |
c7138f37 | 4917 | |
10c6db11 | 4918 | /* |
9bb5d40c PZ |
4919 | * Pin the event->rb by taking event->mmap_mutex; otherwise |
4920 | * perf_event_set_output() can swizzle our rb and make us miss wakeups. | |
10c6db11 PZ |
4921 | */ |
4922 | mutex_lock(&event->mmap_mutex); | |
9bb5d40c PZ |
4923 | rb = event->rb; |
4924 | if (rb) | |
76369139 | 4925 | events = atomic_xchg(&rb->poll, 0); |
10c6db11 | 4926 | mutex_unlock(&event->mmap_mutex); |
0793a61d TG |
4927 | return events; |
4928 | } | |
4929 | ||
f63a8daa | 4930 | static void _perf_event_reset(struct perf_event *event) |
6de6a7b9 | 4931 | { |
7d88962e | 4932 | (void)perf_event_read(event, false); |
e7850595 | 4933 | local64_set(&event->count, 0); |
cdd6c482 | 4934 | perf_event_update_userpage(event); |
3df5edad PZ |
4935 | } |
4936 | ||
c93f7669 | 4937 | /* |
cdd6c482 IM |
4938 | * Holding the top-level event's child_mutex means that any |
4939 | * descendant process that has inherited this event will block | |
8ba289b8 | 4940 | * in perf_event_exit_event() if it goes to exit, thus satisfying the |
cdd6c482 | 4941 | * task existence requirements of perf_event_enable/disable. |
c93f7669 | 4942 | */ |
cdd6c482 IM |
4943 | static void perf_event_for_each_child(struct perf_event *event, |
4944 | void (*func)(struct perf_event *)) | |
3df5edad | 4945 | { |
cdd6c482 | 4946 | struct perf_event *child; |
3df5edad | 4947 | |
cdd6c482 | 4948 | WARN_ON_ONCE(event->ctx->parent_ctx); |
f63a8daa | 4949 | |
cdd6c482 IM |
4950 | mutex_lock(&event->child_mutex); |
4951 | func(event); | |
4952 | list_for_each_entry(child, &event->child_list, child_list) | |
3df5edad | 4953 | func(child); |
cdd6c482 | 4954 | mutex_unlock(&event->child_mutex); |
3df5edad PZ |
4955 | } |
4956 | ||
cdd6c482 IM |
4957 | static void perf_event_for_each(struct perf_event *event, |
4958 | void (*func)(struct perf_event *)) | |
3df5edad | 4959 | { |
cdd6c482 IM |
4960 | struct perf_event_context *ctx = event->ctx; |
4961 | struct perf_event *sibling; | |
3df5edad | 4962 | |
f63a8daa PZ |
4963 | lockdep_assert_held(&ctx->mutex); |
4964 | ||
cdd6c482 | 4965 | event = event->group_leader; |
75f937f2 | 4966 | |
cdd6c482 | 4967 | perf_event_for_each_child(event, func); |
edb39592 | 4968 | for_each_sibling_event(sibling, event) |
724b6daa | 4969 | perf_event_for_each_child(sibling, func); |
6de6a7b9 PZ |
4970 | } |
4971 | ||
fae3fde6 PZ |
4972 | static void __perf_event_period(struct perf_event *event, |
4973 | struct perf_cpu_context *cpuctx, | |
4974 | struct perf_event_context *ctx, | |
4975 | void *info) | |
c7999c6f | 4976 | { |
fae3fde6 | 4977 | u64 value = *((u64 *)info); |
c7999c6f | 4978 | bool active; |
08247e31 | 4979 | |
cdd6c482 | 4980 | if (event->attr.freq) { |
cdd6c482 | 4981 | event->attr.sample_freq = value; |
08247e31 | 4982 | } else { |
cdd6c482 IM |
4983 | event->attr.sample_period = value; |
4984 | event->hw.sample_period = value; | |
08247e31 | 4985 | } |
bad7192b PZ |
4986 | |
4987 | active = (event->state == PERF_EVENT_STATE_ACTIVE); | |
4988 | if (active) { | |
4989 | perf_pmu_disable(ctx->pmu); | |
1e02cd40 PZ |
4990 | /* |
4991 | * We could be throttled; unthrottle now to avoid the tick | |
4992 | * trying to unthrottle while we already re-started the event. | |
4993 | */ | |
4994 | if (event->hw.interrupts == MAX_INTERRUPTS) { | |
4995 | event->hw.interrupts = 0; | |
4996 | perf_log_throttle(event, 1); | |
4997 | } | |
bad7192b PZ |
4998 | event->pmu->stop(event, PERF_EF_UPDATE); |
4999 | } | |
5000 | ||
5001 | local64_set(&event->hw.period_left, 0); | |
5002 | ||
5003 | if (active) { | |
5004 | event->pmu->start(event, PERF_EF_RELOAD); | |
5005 | perf_pmu_enable(ctx->pmu); | |
5006 | } | |
c7999c6f PZ |
5007 | } |
5008 | ||
81ec3f3c JO |
5009 | static int perf_event_check_period(struct perf_event *event, u64 value) |
5010 | { | |
5011 | return event->pmu->check_period(event, value); | |
5012 | } | |
5013 | ||
c7999c6f PZ |
5014 | static int perf_event_period(struct perf_event *event, u64 __user *arg) |
5015 | { | |
c7999c6f PZ |
5016 | u64 value; |
5017 | ||
5018 | if (!is_sampling_event(event)) | |
5019 | return -EINVAL; | |
5020 | ||
5021 | if (copy_from_user(&value, arg, sizeof(value))) | |
5022 | return -EFAULT; | |
5023 | ||
5024 | if (!value) | |
5025 | return -EINVAL; | |
5026 | ||
5027 | if (event->attr.freq && value > sysctl_perf_event_sample_rate) | |
5028 | return -EINVAL; | |
5029 | ||
81ec3f3c JO |
5030 | if (perf_event_check_period(event, value)) |
5031 | return -EINVAL; | |
5032 | ||
913a90bc RB |
5033 | if (!event->attr.freq && (value & (1ULL << 63))) |
5034 | return -EINVAL; | |
5035 | ||
fae3fde6 | 5036 | event_function_call(event, __perf_event_period, &value); |
08247e31 | 5037 | |
c7999c6f | 5038 | return 0; |
08247e31 PZ |
5039 | } |
5040 | ||
ac9721f3 PZ |
5041 | static const struct file_operations perf_fops; |
5042 | ||
2903ff01 | 5043 | static inline int perf_fget_light(int fd, struct fd *p) |
ac9721f3 | 5044 | { |
2903ff01 AV |
5045 | struct fd f = fdget(fd); |
5046 | if (!f.file) | |
5047 | return -EBADF; | |
ac9721f3 | 5048 | |
2903ff01 AV |
5049 | if (f.file->f_op != &perf_fops) { |
5050 | fdput(f); | |
5051 | return -EBADF; | |
ac9721f3 | 5052 | } |
2903ff01 AV |
5053 | *p = f; |
5054 | return 0; | |
ac9721f3 PZ |
5055 | } |
5056 | ||
5057 | static int perf_event_set_output(struct perf_event *event, | |
5058 | struct perf_event *output_event); | |
6fb2915d | 5059 | static int perf_event_set_filter(struct perf_event *event, void __user *arg); |
2541517c | 5060 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd); |
32ff77e8 MC |
5061 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
5062 | struct perf_event_attr *attr); | |
a4be7c27 | 5063 | |
f63a8daa | 5064 | static long _perf_ioctl(struct perf_event *event, unsigned int cmd, unsigned long arg) |
d859e29f | 5065 | { |
cdd6c482 | 5066 | void (*func)(struct perf_event *); |
3df5edad | 5067 | u32 flags = arg; |
d859e29f PM |
5068 | |
5069 | switch (cmd) { | |
cdd6c482 | 5070 | case PERF_EVENT_IOC_ENABLE: |
f63a8daa | 5071 | func = _perf_event_enable; |
d859e29f | 5072 | break; |
cdd6c482 | 5073 | case PERF_EVENT_IOC_DISABLE: |
f63a8daa | 5074 | func = _perf_event_disable; |
79f14641 | 5075 | break; |
cdd6c482 | 5076 | case PERF_EVENT_IOC_RESET: |
f63a8daa | 5077 | func = _perf_event_reset; |
6de6a7b9 | 5078 | break; |
3df5edad | 5079 | |
cdd6c482 | 5080 | case PERF_EVENT_IOC_REFRESH: |
f63a8daa | 5081 | return _perf_event_refresh(event, arg); |
08247e31 | 5082 | |
cdd6c482 IM |
5083 | case PERF_EVENT_IOC_PERIOD: |
5084 | return perf_event_period(event, (u64 __user *)arg); | |
08247e31 | 5085 | |
cf4957f1 JO |
5086 | case PERF_EVENT_IOC_ID: |
5087 | { | |
5088 | u64 id = primary_event_id(event); | |
5089 | ||
5090 | if (copy_to_user((void __user *)arg, &id, sizeof(id))) | |
5091 | return -EFAULT; | |
5092 | return 0; | |
5093 | } | |
5094 | ||
cdd6c482 | 5095 | case PERF_EVENT_IOC_SET_OUTPUT: |
ac9721f3 | 5096 | { |
ac9721f3 | 5097 | int ret; |
ac9721f3 | 5098 | if (arg != -1) { |
2903ff01 AV |
5099 | struct perf_event *output_event; |
5100 | struct fd output; | |
5101 | ret = perf_fget_light(arg, &output); | |
5102 | if (ret) | |
5103 | return ret; | |
5104 | output_event = output.file->private_data; | |
5105 | ret = perf_event_set_output(event, output_event); | |
5106 | fdput(output); | |
5107 | } else { | |
5108 | ret = perf_event_set_output(event, NULL); | |
ac9721f3 | 5109 | } |
ac9721f3 PZ |
5110 | return ret; |
5111 | } | |
a4be7c27 | 5112 | |
6fb2915d LZ |
5113 | case PERF_EVENT_IOC_SET_FILTER: |
5114 | return perf_event_set_filter(event, (void __user *)arg); | |
5115 | ||
2541517c AS |
5116 | case PERF_EVENT_IOC_SET_BPF: |
5117 | return perf_event_set_bpf_prog(event, arg); | |
5118 | ||
86e7972f WN |
5119 | case PERF_EVENT_IOC_PAUSE_OUTPUT: { |
5120 | struct ring_buffer *rb; | |
5121 | ||
5122 | rcu_read_lock(); | |
5123 | rb = rcu_dereference(event->rb); | |
5124 | if (!rb || !rb->nr_pages) { | |
5125 | rcu_read_unlock(); | |
5126 | return -EINVAL; | |
5127 | } | |
5128 | rb_toggle_paused(rb, !!arg); | |
5129 | rcu_read_unlock(); | |
5130 | return 0; | |
5131 | } | |
f371b304 YS |
5132 | |
5133 | case PERF_EVENT_IOC_QUERY_BPF: | |
f4e2298e | 5134 | return perf_event_query_prog_array(event, (void __user *)arg); |
32ff77e8 MC |
5135 | |
5136 | case PERF_EVENT_IOC_MODIFY_ATTRIBUTES: { | |
5137 | struct perf_event_attr new_attr; | |
5138 | int err = perf_copy_attr((struct perf_event_attr __user *)arg, | |
5139 | &new_attr); | |
5140 | ||
5141 | if (err) | |
5142 | return err; | |
5143 | ||
5144 | return perf_event_modify_attr(event, &new_attr); | |
5145 | } | |
d859e29f | 5146 | default: |
3df5edad | 5147 | return -ENOTTY; |
d859e29f | 5148 | } |
3df5edad PZ |
5149 | |
5150 | if (flags & PERF_IOC_FLAG_GROUP) | |
cdd6c482 | 5151 | perf_event_for_each(event, func); |
3df5edad | 5152 | else |
cdd6c482 | 5153 | perf_event_for_each_child(event, func); |
3df5edad PZ |
5154 | |
5155 | return 0; | |
d859e29f PM |
5156 | } |
5157 | ||
f63a8daa PZ |
5158 | static long perf_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
5159 | { | |
5160 | struct perf_event *event = file->private_data; | |
5161 | struct perf_event_context *ctx; | |
5162 | long ret; | |
5163 | ||
5164 | ctx = perf_event_ctx_lock(event); | |
5165 | ret = _perf_ioctl(event, cmd, arg); | |
5166 | perf_event_ctx_unlock(event, ctx); | |
5167 | ||
5168 | return ret; | |
5169 | } | |
5170 | ||
b3f20785 PM |
5171 | #ifdef CONFIG_COMPAT |
5172 | static long perf_compat_ioctl(struct file *file, unsigned int cmd, | |
5173 | unsigned long arg) | |
5174 | { | |
5175 | switch (_IOC_NR(cmd)) { | |
5176 | case _IOC_NR(PERF_EVENT_IOC_SET_FILTER): | |
5177 | case _IOC_NR(PERF_EVENT_IOC_ID): | |
82489c5f ES |
5178 | case _IOC_NR(PERF_EVENT_IOC_QUERY_BPF): |
5179 | case _IOC_NR(PERF_EVENT_IOC_MODIFY_ATTRIBUTES): | |
b3f20785 PM |
5180 | /* Fix up pointer size (usually 4 -> 8 in 32-on-64-bit case */ |
5181 | if (_IOC_SIZE(cmd) == sizeof(compat_uptr_t)) { | |
5182 | cmd &= ~IOCSIZE_MASK; | |
5183 | cmd |= sizeof(void *) << IOCSIZE_SHIFT; | |
5184 | } | |
5185 | break; | |
5186 | } | |
5187 | return perf_ioctl(file, cmd, arg); | |
5188 | } | |
5189 | #else | |
5190 | # define perf_compat_ioctl NULL | |
5191 | #endif | |
5192 | ||
cdd6c482 | 5193 | int perf_event_task_enable(void) |
771d7cde | 5194 | { |
f63a8daa | 5195 | struct perf_event_context *ctx; |
cdd6c482 | 5196 | struct perf_event *event; |
771d7cde | 5197 | |
cdd6c482 | 5198 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
5199 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
5200 | ctx = perf_event_ctx_lock(event); | |
5201 | perf_event_for_each_child(event, _perf_event_enable); | |
5202 | perf_event_ctx_unlock(event, ctx); | |
5203 | } | |
cdd6c482 | 5204 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
5205 | |
5206 | return 0; | |
5207 | } | |
5208 | ||
cdd6c482 | 5209 | int perf_event_task_disable(void) |
771d7cde | 5210 | { |
f63a8daa | 5211 | struct perf_event_context *ctx; |
cdd6c482 | 5212 | struct perf_event *event; |
771d7cde | 5213 | |
cdd6c482 | 5214 | mutex_lock(¤t->perf_event_mutex); |
f63a8daa PZ |
5215 | list_for_each_entry(event, ¤t->perf_event_list, owner_entry) { |
5216 | ctx = perf_event_ctx_lock(event); | |
5217 | perf_event_for_each_child(event, _perf_event_disable); | |
5218 | perf_event_ctx_unlock(event, ctx); | |
5219 | } | |
cdd6c482 | 5220 | mutex_unlock(¤t->perf_event_mutex); |
771d7cde PZ |
5221 | |
5222 | return 0; | |
5223 | } | |
5224 | ||
cdd6c482 | 5225 | static int perf_event_index(struct perf_event *event) |
194002b2 | 5226 | { |
a4eaf7f1 PZ |
5227 | if (event->hw.state & PERF_HES_STOPPED) |
5228 | return 0; | |
5229 | ||
cdd6c482 | 5230 | if (event->state != PERF_EVENT_STATE_ACTIVE) |
194002b2 PZ |
5231 | return 0; |
5232 | ||
35edc2a5 | 5233 | return event->pmu->event_idx(event); |
194002b2 PZ |
5234 | } |
5235 | ||
c4794295 | 5236 | static void calc_timer_values(struct perf_event *event, |
e3f3541c | 5237 | u64 *now, |
7f310a5d EM |
5238 | u64 *enabled, |
5239 | u64 *running) | |
c4794295 | 5240 | { |
e3f3541c | 5241 | u64 ctx_time; |
c4794295 | 5242 | |
e3f3541c PZ |
5243 | *now = perf_clock(); |
5244 | ctx_time = event->shadow_ctx_time + *now; | |
0d3d73aa | 5245 | __perf_update_times(event, ctx_time, enabled, running); |
c4794295 EM |
5246 | } |
5247 | ||
fa731587 PZ |
5248 | static void perf_event_init_userpage(struct perf_event *event) |
5249 | { | |
5250 | struct perf_event_mmap_page *userpg; | |
5251 | struct ring_buffer *rb; | |
5252 | ||
5253 | rcu_read_lock(); | |
5254 | rb = rcu_dereference(event->rb); | |
5255 | if (!rb) | |
5256 | goto unlock; | |
5257 | ||
5258 | userpg = rb->user_page; | |
5259 | ||
5260 | /* Allow new userspace to detect that bit 0 is deprecated */ | |
5261 | userpg->cap_bit0_is_deprecated = 1; | |
5262 | userpg->size = offsetof(struct perf_event_mmap_page, __reserved); | |
e8c6deac AS |
5263 | userpg->data_offset = PAGE_SIZE; |
5264 | userpg->data_size = perf_data_size(rb); | |
fa731587 PZ |
5265 | |
5266 | unlock: | |
5267 | rcu_read_unlock(); | |
5268 | } | |
5269 | ||
c1317ec2 AL |
5270 | void __weak arch_perf_update_userpage( |
5271 | struct perf_event *event, struct perf_event_mmap_page *userpg, u64 now) | |
e3f3541c PZ |
5272 | { |
5273 | } | |
5274 | ||
38ff667b PZ |
5275 | /* |
5276 | * Callers need to ensure there can be no nesting of this function, otherwise | |
5277 | * the seqlock logic goes bad. We can not serialize this because the arch | |
5278 | * code calls this from NMI context. | |
5279 | */ | |
cdd6c482 | 5280 | void perf_event_update_userpage(struct perf_event *event) |
37d81828 | 5281 | { |
cdd6c482 | 5282 | struct perf_event_mmap_page *userpg; |
76369139 | 5283 | struct ring_buffer *rb; |
e3f3541c | 5284 | u64 enabled, running, now; |
38ff667b PZ |
5285 | |
5286 | rcu_read_lock(); | |
5ec4c599 PZ |
5287 | rb = rcu_dereference(event->rb); |
5288 | if (!rb) | |
5289 | goto unlock; | |
5290 | ||
0d641208 EM |
5291 | /* |
5292 | * compute total_time_enabled, total_time_running | |
5293 | * based on snapshot values taken when the event | |
5294 | * was last scheduled in. | |
5295 | * | |
5296 | * we cannot simply called update_context_time() | |
5297 | * because of locking issue as we can be called in | |
5298 | * NMI context | |
5299 | */ | |
e3f3541c | 5300 | calc_timer_values(event, &now, &enabled, &running); |
38ff667b | 5301 | |
76369139 | 5302 | userpg = rb->user_page; |
7b732a75 | 5303 | /* |
9d2dcc8f MF |
5304 | * Disable preemption to guarantee consistent time stamps are stored to |
5305 | * the user page. | |
7b732a75 PZ |
5306 | */ |
5307 | preempt_disable(); | |
37d81828 | 5308 | ++userpg->lock; |
92f22a38 | 5309 | barrier(); |
cdd6c482 | 5310 | userpg->index = perf_event_index(event); |
b5e58793 | 5311 | userpg->offset = perf_event_count(event); |
365a4038 | 5312 | if (userpg->index) |
e7850595 | 5313 | userpg->offset -= local64_read(&event->hw.prev_count); |
7b732a75 | 5314 | |
0d641208 | 5315 | userpg->time_enabled = enabled + |
cdd6c482 | 5316 | atomic64_read(&event->child_total_time_enabled); |
7f8b4e4e | 5317 | |
0d641208 | 5318 | userpg->time_running = running + |
cdd6c482 | 5319 | atomic64_read(&event->child_total_time_running); |
7f8b4e4e | 5320 | |
c1317ec2 | 5321 | arch_perf_update_userpage(event, userpg, now); |
e3f3541c | 5322 | |
92f22a38 | 5323 | barrier(); |
37d81828 | 5324 | ++userpg->lock; |
7b732a75 | 5325 | preempt_enable(); |
38ff667b | 5326 | unlock: |
7b732a75 | 5327 | rcu_read_unlock(); |
37d81828 | 5328 | } |
82975c46 | 5329 | EXPORT_SYMBOL_GPL(perf_event_update_userpage); |
37d81828 | 5330 | |
9e3ed2d7 | 5331 | static vm_fault_t perf_mmap_fault(struct vm_fault *vmf) |
906010b2 | 5332 | { |
11bac800 | 5333 | struct perf_event *event = vmf->vma->vm_file->private_data; |
76369139 | 5334 | struct ring_buffer *rb; |
9e3ed2d7 | 5335 | vm_fault_t ret = VM_FAULT_SIGBUS; |
906010b2 PZ |
5336 | |
5337 | if (vmf->flags & FAULT_FLAG_MKWRITE) { | |
5338 | if (vmf->pgoff == 0) | |
5339 | ret = 0; | |
5340 | return ret; | |
5341 | } | |
5342 | ||
5343 | rcu_read_lock(); | |
76369139 FW |
5344 | rb = rcu_dereference(event->rb); |
5345 | if (!rb) | |
906010b2 PZ |
5346 | goto unlock; |
5347 | ||
5348 | if (vmf->pgoff && (vmf->flags & FAULT_FLAG_WRITE)) | |
5349 | goto unlock; | |
5350 | ||
76369139 | 5351 | vmf->page = perf_mmap_to_page(rb, vmf->pgoff); |
906010b2 PZ |
5352 | if (!vmf->page) |
5353 | goto unlock; | |
5354 | ||
5355 | get_page(vmf->page); | |
11bac800 | 5356 | vmf->page->mapping = vmf->vma->vm_file->f_mapping; |
906010b2 PZ |
5357 | vmf->page->index = vmf->pgoff; |
5358 | ||
5359 | ret = 0; | |
5360 | unlock: | |
5361 | rcu_read_unlock(); | |
5362 | ||
5363 | return ret; | |
5364 | } | |
5365 | ||
10c6db11 PZ |
5366 | static void ring_buffer_attach(struct perf_event *event, |
5367 | struct ring_buffer *rb) | |
5368 | { | |
b69cf536 | 5369 | struct ring_buffer *old_rb = NULL; |
10c6db11 PZ |
5370 | unsigned long flags; |
5371 | ||
b69cf536 PZ |
5372 | if (event->rb) { |
5373 | /* | |
5374 | * Should be impossible, we set this when removing | |
5375 | * event->rb_entry and wait/clear when adding event->rb_entry. | |
5376 | */ | |
5377 | WARN_ON_ONCE(event->rcu_pending); | |
10c6db11 | 5378 | |
b69cf536 | 5379 | old_rb = event->rb; |
b69cf536 PZ |
5380 | spin_lock_irqsave(&old_rb->event_lock, flags); |
5381 | list_del_rcu(&event->rb_entry); | |
5382 | spin_unlock_irqrestore(&old_rb->event_lock, flags); | |
10c6db11 | 5383 | |
2f993cf0 ON |
5384 | event->rcu_batches = get_state_synchronize_rcu(); |
5385 | event->rcu_pending = 1; | |
b69cf536 | 5386 | } |
10c6db11 | 5387 | |
b69cf536 | 5388 | if (rb) { |
2f993cf0 ON |
5389 | if (event->rcu_pending) { |
5390 | cond_synchronize_rcu(event->rcu_batches); | |
5391 | event->rcu_pending = 0; | |
5392 | } | |
5393 | ||
b69cf536 PZ |
5394 | spin_lock_irqsave(&rb->event_lock, flags); |
5395 | list_add_rcu(&event->rb_entry, &rb->event_list); | |
5396 | spin_unlock_irqrestore(&rb->event_lock, flags); | |
5397 | } | |
5398 | ||
767ae086 AS |
5399 | /* |
5400 | * Avoid racing with perf_mmap_close(AUX): stop the event | |
5401 | * before swizzling the event::rb pointer; if it's getting | |
5402 | * unmapped, its aux_mmap_count will be 0 and it won't | |
5403 | * restart. See the comment in __perf_pmu_output_stop(). | |
5404 | * | |
5405 | * Data will inevitably be lost when set_output is done in | |
5406 | * mid-air, but then again, whoever does it like this is | |
5407 | * not in for the data anyway. | |
5408 | */ | |
5409 | if (has_aux(event)) | |
5410 | perf_event_stop(event, 0); | |
5411 | ||
b69cf536 PZ |
5412 | rcu_assign_pointer(event->rb, rb); |
5413 | ||
5414 | if (old_rb) { | |
5415 | ring_buffer_put(old_rb); | |
5416 | /* | |
5417 | * Since we detached before setting the new rb, so that we | |
5418 | * could attach the new rb, we could have missed a wakeup. | |
5419 | * Provide it now. | |
5420 | */ | |
5421 | wake_up_all(&event->waitq); | |
5422 | } | |
10c6db11 PZ |
5423 | } |
5424 | ||
5425 | static void ring_buffer_wakeup(struct perf_event *event) | |
5426 | { | |
5427 | struct ring_buffer *rb; | |
5428 | ||
5429 | rcu_read_lock(); | |
5430 | rb = rcu_dereference(event->rb); | |
9bb5d40c PZ |
5431 | if (rb) { |
5432 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) | |
5433 | wake_up_all(&event->waitq); | |
5434 | } | |
10c6db11 PZ |
5435 | rcu_read_unlock(); |
5436 | } | |
5437 | ||
fdc26706 | 5438 | struct ring_buffer *ring_buffer_get(struct perf_event *event) |
7b732a75 | 5439 | { |
76369139 | 5440 | struct ring_buffer *rb; |
7b732a75 | 5441 | |
ac9721f3 | 5442 | rcu_read_lock(); |
76369139 FW |
5443 | rb = rcu_dereference(event->rb); |
5444 | if (rb) { | |
fecb8ed2 | 5445 | if (!refcount_inc_not_zero(&rb->refcount)) |
76369139 | 5446 | rb = NULL; |
ac9721f3 PZ |
5447 | } |
5448 | rcu_read_unlock(); | |
5449 | ||
76369139 | 5450 | return rb; |
ac9721f3 PZ |
5451 | } |
5452 | ||
fdc26706 | 5453 | void ring_buffer_put(struct ring_buffer *rb) |
ac9721f3 | 5454 | { |
fecb8ed2 | 5455 | if (!refcount_dec_and_test(&rb->refcount)) |
ac9721f3 | 5456 | return; |
7b732a75 | 5457 | |
9bb5d40c | 5458 | WARN_ON_ONCE(!list_empty(&rb->event_list)); |
10c6db11 | 5459 | |
76369139 | 5460 | call_rcu(&rb->rcu_head, rb_free_rcu); |
7b732a75 PZ |
5461 | } |
5462 | ||
5463 | static void perf_mmap_open(struct vm_area_struct *vma) | |
5464 | { | |
cdd6c482 | 5465 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 5466 | |
cdd6c482 | 5467 | atomic_inc(&event->mmap_count); |
9bb5d40c | 5468 | atomic_inc(&event->rb->mmap_count); |
1e0fb9ec | 5469 | |
45bfb2e5 PZ |
5470 | if (vma->vm_pgoff) |
5471 | atomic_inc(&event->rb->aux_mmap_count); | |
5472 | ||
1e0fb9ec | 5473 | if (event->pmu->event_mapped) |
bfe33492 | 5474 | event->pmu->event_mapped(event, vma->vm_mm); |
7b732a75 PZ |
5475 | } |
5476 | ||
95ff4ca2 AS |
5477 | static void perf_pmu_output_stop(struct perf_event *event); |
5478 | ||
9bb5d40c PZ |
5479 | /* |
5480 | * A buffer can be mmap()ed multiple times; either directly through the same | |
5481 | * event, or through other events by use of perf_event_set_output(). | |
5482 | * | |
5483 | * In order to undo the VM accounting done by perf_mmap() we need to destroy | |
5484 | * the buffer here, where we still have a VM context. This means we need | |
5485 | * to detach all events redirecting to us. | |
5486 | */ | |
7b732a75 PZ |
5487 | static void perf_mmap_close(struct vm_area_struct *vma) |
5488 | { | |
cdd6c482 | 5489 | struct perf_event *event = vma->vm_file->private_data; |
7b732a75 | 5490 | |
b69cf536 | 5491 | struct ring_buffer *rb = ring_buffer_get(event); |
9bb5d40c PZ |
5492 | struct user_struct *mmap_user = rb->mmap_user; |
5493 | int mmap_locked = rb->mmap_locked; | |
5494 | unsigned long size = perf_data_size(rb); | |
789f90fc | 5495 | |
1e0fb9ec | 5496 | if (event->pmu->event_unmapped) |
bfe33492 | 5497 | event->pmu->event_unmapped(event, vma->vm_mm); |
1e0fb9ec | 5498 | |
45bfb2e5 PZ |
5499 | /* |
5500 | * rb->aux_mmap_count will always drop before rb->mmap_count and | |
5501 | * event->mmap_count, so it is ok to use event->mmap_mutex to | |
5502 | * serialize with perf_mmap here. | |
5503 | */ | |
5504 | if (rb_has_aux(rb) && vma->vm_pgoff == rb->aux_pgoff && | |
5505 | atomic_dec_and_mutex_lock(&rb->aux_mmap_count, &event->mmap_mutex)) { | |
95ff4ca2 AS |
5506 | /* |
5507 | * Stop all AUX events that are writing to this buffer, | |
5508 | * so that we can free its AUX pages and corresponding PMU | |
5509 | * data. Note that after rb::aux_mmap_count dropped to zero, | |
5510 | * they won't start any more (see perf_aux_output_begin()). | |
5511 | */ | |
5512 | perf_pmu_output_stop(event); | |
5513 | ||
5514 | /* now it's safe to free the pages */ | |
45bfb2e5 | 5515 | atomic_long_sub(rb->aux_nr_pages, &mmap_user->locked_vm); |
70f8a3ca | 5516 | atomic64_sub(rb->aux_mmap_locked, &vma->vm_mm->pinned_vm); |
45bfb2e5 | 5517 | |
95ff4ca2 | 5518 | /* this has to be the last one */ |
45bfb2e5 | 5519 | rb_free_aux(rb); |
ca3bb3d0 | 5520 | WARN_ON_ONCE(refcount_read(&rb->aux_refcount)); |
95ff4ca2 | 5521 | |
45bfb2e5 PZ |
5522 | mutex_unlock(&event->mmap_mutex); |
5523 | } | |
5524 | ||
9bb5d40c PZ |
5525 | atomic_dec(&rb->mmap_count); |
5526 | ||
5527 | if (!atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex)) | |
b69cf536 | 5528 | goto out_put; |
9bb5d40c | 5529 | |
b69cf536 | 5530 | ring_buffer_attach(event, NULL); |
9bb5d40c PZ |
5531 | mutex_unlock(&event->mmap_mutex); |
5532 | ||
5533 | /* If there's still other mmap()s of this buffer, we're done. */ | |
b69cf536 PZ |
5534 | if (atomic_read(&rb->mmap_count)) |
5535 | goto out_put; | |
ac9721f3 | 5536 | |
9bb5d40c PZ |
5537 | /* |
5538 | * No other mmap()s, detach from all other events that might redirect | |
5539 | * into the now unreachable buffer. Somewhat complicated by the | |
5540 | * fact that rb::event_lock otherwise nests inside mmap_mutex. | |
5541 | */ | |
5542 | again: | |
5543 | rcu_read_lock(); | |
5544 | list_for_each_entry_rcu(event, &rb->event_list, rb_entry) { | |
5545 | if (!atomic_long_inc_not_zero(&event->refcount)) { | |
5546 | /* | |
5547 | * This event is en-route to free_event() which will | |
5548 | * detach it and remove it from the list. | |
5549 | */ | |
5550 | continue; | |
5551 | } | |
5552 | rcu_read_unlock(); | |
789f90fc | 5553 | |
9bb5d40c PZ |
5554 | mutex_lock(&event->mmap_mutex); |
5555 | /* | |
5556 | * Check we didn't race with perf_event_set_output() which can | |
5557 | * swizzle the rb from under us while we were waiting to | |
5558 | * acquire mmap_mutex. | |
5559 | * | |
5560 | * If we find a different rb; ignore this event, a next | |
5561 | * iteration will no longer find it on the list. We have to | |
5562 | * still restart the iteration to make sure we're not now | |
5563 | * iterating the wrong list. | |
5564 | */ | |
b69cf536 PZ |
5565 | if (event->rb == rb) |
5566 | ring_buffer_attach(event, NULL); | |
5567 | ||
cdd6c482 | 5568 | mutex_unlock(&event->mmap_mutex); |
9bb5d40c | 5569 | put_event(event); |
ac9721f3 | 5570 | |
9bb5d40c PZ |
5571 | /* |
5572 | * Restart the iteration; either we're on the wrong list or | |
5573 | * destroyed its integrity by doing a deletion. | |
5574 | */ | |
5575 | goto again; | |
7b732a75 | 5576 | } |
9bb5d40c PZ |
5577 | rcu_read_unlock(); |
5578 | ||
5579 | /* | |
5580 | * It could be there's still a few 0-ref events on the list; they'll | |
5581 | * get cleaned up by free_event() -- they'll also still have their | |
5582 | * ref on the rb and will free it whenever they are done with it. | |
5583 | * | |
5584 | * Aside from that, this buffer is 'fully' detached and unmapped, | |
5585 | * undo the VM accounting. | |
5586 | */ | |
5587 | ||
5588 | atomic_long_sub((size >> PAGE_SHIFT) + 1, &mmap_user->locked_vm); | |
70f8a3ca | 5589 | atomic64_sub(mmap_locked, &vma->vm_mm->pinned_vm); |
9bb5d40c PZ |
5590 | free_uid(mmap_user); |
5591 | ||
b69cf536 | 5592 | out_put: |
9bb5d40c | 5593 | ring_buffer_put(rb); /* could be last */ |
37d81828 PM |
5594 | } |
5595 | ||
f0f37e2f | 5596 | static const struct vm_operations_struct perf_mmap_vmops = { |
43a21ea8 | 5597 | .open = perf_mmap_open, |
fca0c116 | 5598 | .close = perf_mmap_close, /* non mergeable */ |
43a21ea8 PZ |
5599 | .fault = perf_mmap_fault, |
5600 | .page_mkwrite = perf_mmap_fault, | |
37d81828 PM |
5601 | }; |
5602 | ||
5603 | static int perf_mmap(struct file *file, struct vm_area_struct *vma) | |
5604 | { | |
cdd6c482 | 5605 | struct perf_event *event = file->private_data; |
22a4f650 | 5606 | unsigned long user_locked, user_lock_limit; |
789f90fc | 5607 | struct user_struct *user = current_user(); |
22a4f650 | 5608 | unsigned long locked, lock_limit; |
45bfb2e5 | 5609 | struct ring_buffer *rb = NULL; |
7b732a75 PZ |
5610 | unsigned long vma_size; |
5611 | unsigned long nr_pages; | |
45bfb2e5 | 5612 | long user_extra = 0, extra = 0; |
d57e34fd | 5613 | int ret = 0, flags = 0; |
37d81828 | 5614 | |
c7920614 PZ |
5615 | /* |
5616 | * Don't allow mmap() of inherited per-task counters. This would | |
5617 | * create a performance issue due to all children writing to the | |
76369139 | 5618 | * same rb. |
c7920614 PZ |
5619 | */ |
5620 | if (event->cpu == -1 && event->attr.inherit) | |
5621 | return -EINVAL; | |
5622 | ||
43a21ea8 | 5623 | if (!(vma->vm_flags & VM_SHARED)) |
37d81828 | 5624 | return -EINVAL; |
7b732a75 PZ |
5625 | |
5626 | vma_size = vma->vm_end - vma->vm_start; | |
45bfb2e5 PZ |
5627 | |
5628 | if (vma->vm_pgoff == 0) { | |
5629 | nr_pages = (vma_size / PAGE_SIZE) - 1; | |
5630 | } else { | |
5631 | /* | |
5632 | * AUX area mapping: if rb->aux_nr_pages != 0, it's already | |
5633 | * mapped, all subsequent mappings should have the same size | |
5634 | * and offset. Must be above the normal perf buffer. | |
5635 | */ | |
5636 | u64 aux_offset, aux_size; | |
5637 | ||
5638 | if (!event->rb) | |
5639 | return -EINVAL; | |
5640 | ||
5641 | nr_pages = vma_size / PAGE_SIZE; | |
5642 | ||
5643 | mutex_lock(&event->mmap_mutex); | |
5644 | ret = -EINVAL; | |
5645 | ||
5646 | rb = event->rb; | |
5647 | if (!rb) | |
5648 | goto aux_unlock; | |
5649 | ||
6aa7de05 MR |
5650 | aux_offset = READ_ONCE(rb->user_page->aux_offset); |
5651 | aux_size = READ_ONCE(rb->user_page->aux_size); | |
45bfb2e5 PZ |
5652 | |
5653 | if (aux_offset < perf_data_size(rb) + PAGE_SIZE) | |
5654 | goto aux_unlock; | |
5655 | ||
5656 | if (aux_offset != vma->vm_pgoff << PAGE_SHIFT) | |
5657 | goto aux_unlock; | |
5658 | ||
5659 | /* already mapped with a different offset */ | |
5660 | if (rb_has_aux(rb) && rb->aux_pgoff != vma->vm_pgoff) | |
5661 | goto aux_unlock; | |
5662 | ||
5663 | if (aux_size != vma_size || aux_size != nr_pages * PAGE_SIZE) | |
5664 | goto aux_unlock; | |
5665 | ||
5666 | /* already mapped with a different size */ | |
5667 | if (rb_has_aux(rb) && rb->aux_nr_pages != nr_pages) | |
5668 | goto aux_unlock; | |
5669 | ||
5670 | if (!is_power_of_2(nr_pages)) | |
5671 | goto aux_unlock; | |
5672 | ||
5673 | if (!atomic_inc_not_zero(&rb->mmap_count)) | |
5674 | goto aux_unlock; | |
5675 | ||
5676 | if (rb_has_aux(rb)) { | |
5677 | atomic_inc(&rb->aux_mmap_count); | |
5678 | ret = 0; | |
5679 | goto unlock; | |
5680 | } | |
5681 | ||
5682 | atomic_set(&rb->aux_mmap_count, 1); | |
5683 | user_extra = nr_pages; | |
5684 | ||
5685 | goto accounting; | |
5686 | } | |
7b732a75 | 5687 | |
7730d865 | 5688 | /* |
76369139 | 5689 | * If we have rb pages ensure they're a power-of-two number, so we |
7730d865 PZ |
5690 | * can do bitmasks instead of modulo. |
5691 | */ | |
2ed11312 | 5692 | if (nr_pages != 0 && !is_power_of_2(nr_pages)) |
37d81828 PM |
5693 | return -EINVAL; |
5694 | ||
7b732a75 | 5695 | if (vma_size != PAGE_SIZE * (1 + nr_pages)) |
37d81828 PM |
5696 | return -EINVAL; |
5697 | ||
cdd6c482 | 5698 | WARN_ON_ONCE(event->ctx->parent_ctx); |
9bb5d40c | 5699 | again: |
cdd6c482 | 5700 | mutex_lock(&event->mmap_mutex); |
76369139 | 5701 | if (event->rb) { |
9bb5d40c | 5702 | if (event->rb->nr_pages != nr_pages) { |
ebb3c4c4 | 5703 | ret = -EINVAL; |
9bb5d40c PZ |
5704 | goto unlock; |
5705 | } | |
5706 | ||
5707 | if (!atomic_inc_not_zero(&event->rb->mmap_count)) { | |
5708 | /* | |
5709 | * Raced against perf_mmap_close() through | |
5710 | * perf_event_set_output(). Try again, hope for better | |
5711 | * luck. | |
5712 | */ | |
5713 | mutex_unlock(&event->mmap_mutex); | |
5714 | goto again; | |
5715 | } | |
5716 | ||
ebb3c4c4 PZ |
5717 | goto unlock; |
5718 | } | |
5719 | ||
789f90fc | 5720 | user_extra = nr_pages + 1; |
45bfb2e5 PZ |
5721 | |
5722 | accounting: | |
cdd6c482 | 5723 | user_lock_limit = sysctl_perf_event_mlock >> (PAGE_SHIFT - 10); |
a3862d3f IM |
5724 | |
5725 | /* | |
5726 | * Increase the limit linearly with more CPUs: | |
5727 | */ | |
5728 | user_lock_limit *= num_online_cpus(); | |
5729 | ||
789f90fc | 5730 | user_locked = atomic_long_read(&user->locked_vm) + user_extra; |
c5078f78 | 5731 | |
789f90fc PZ |
5732 | if (user_locked > user_lock_limit) |
5733 | extra = user_locked - user_lock_limit; | |
7b732a75 | 5734 | |
78d7d407 | 5735 | lock_limit = rlimit(RLIMIT_MEMLOCK); |
7b732a75 | 5736 | lock_limit >>= PAGE_SHIFT; |
70f8a3ca | 5737 | locked = atomic64_read(&vma->vm_mm->pinned_vm) + extra; |
7b732a75 | 5738 | |
459ec28a IM |
5739 | if ((locked > lock_limit) && perf_paranoid_tracepoint_raw() && |
5740 | !capable(CAP_IPC_LOCK)) { | |
ebb3c4c4 PZ |
5741 | ret = -EPERM; |
5742 | goto unlock; | |
5743 | } | |
7b732a75 | 5744 | |
45bfb2e5 | 5745 | WARN_ON(!rb && event->rb); |
906010b2 | 5746 | |
d57e34fd | 5747 | if (vma->vm_flags & VM_WRITE) |
76369139 | 5748 | flags |= RING_BUFFER_WRITABLE; |
d57e34fd | 5749 | |
76369139 | 5750 | if (!rb) { |
45bfb2e5 PZ |
5751 | rb = rb_alloc(nr_pages, |
5752 | event->attr.watermark ? event->attr.wakeup_watermark : 0, | |
5753 | event->cpu, flags); | |
26cb63ad | 5754 | |
45bfb2e5 PZ |
5755 | if (!rb) { |
5756 | ret = -ENOMEM; | |
5757 | goto unlock; | |
5758 | } | |
43a21ea8 | 5759 | |
45bfb2e5 PZ |
5760 | atomic_set(&rb->mmap_count, 1); |
5761 | rb->mmap_user = get_current_user(); | |
5762 | rb->mmap_locked = extra; | |
26cb63ad | 5763 | |
45bfb2e5 | 5764 | ring_buffer_attach(event, rb); |
ac9721f3 | 5765 | |
45bfb2e5 PZ |
5766 | perf_event_init_userpage(event); |
5767 | perf_event_update_userpage(event); | |
5768 | } else { | |
1a594131 AS |
5769 | ret = rb_alloc_aux(rb, event, vma->vm_pgoff, nr_pages, |
5770 | event->attr.aux_watermark, flags); | |
45bfb2e5 PZ |
5771 | if (!ret) |
5772 | rb->aux_mmap_locked = extra; | |
5773 | } | |
9a0f05cb | 5774 | |
ebb3c4c4 | 5775 | unlock: |
45bfb2e5 PZ |
5776 | if (!ret) { |
5777 | atomic_long_add(user_extra, &user->locked_vm); | |
70f8a3ca | 5778 | atomic64_add(extra, &vma->vm_mm->pinned_vm); |
45bfb2e5 | 5779 | |
ac9721f3 | 5780 | atomic_inc(&event->mmap_count); |
45bfb2e5 PZ |
5781 | } else if (rb) { |
5782 | atomic_dec(&rb->mmap_count); | |
5783 | } | |
5784 | aux_unlock: | |
cdd6c482 | 5785 | mutex_unlock(&event->mmap_mutex); |
37d81828 | 5786 | |
9bb5d40c PZ |
5787 | /* |
5788 | * Since pinned accounting is per vm we cannot allow fork() to copy our | |
5789 | * vma. | |
5790 | */ | |
26cb63ad | 5791 | vma->vm_flags |= VM_DONTCOPY | VM_DONTEXPAND | VM_DONTDUMP; |
37d81828 | 5792 | vma->vm_ops = &perf_mmap_vmops; |
7b732a75 | 5793 | |
1e0fb9ec | 5794 | if (event->pmu->event_mapped) |
bfe33492 | 5795 | event->pmu->event_mapped(event, vma->vm_mm); |
1e0fb9ec | 5796 | |
7b732a75 | 5797 | return ret; |
37d81828 PM |
5798 | } |
5799 | ||
3c446b3d PZ |
5800 | static int perf_fasync(int fd, struct file *filp, int on) |
5801 | { | |
496ad9aa | 5802 | struct inode *inode = file_inode(filp); |
cdd6c482 | 5803 | struct perf_event *event = filp->private_data; |
3c446b3d PZ |
5804 | int retval; |
5805 | ||
5955102c | 5806 | inode_lock(inode); |
cdd6c482 | 5807 | retval = fasync_helper(fd, filp, on, &event->fasync); |
5955102c | 5808 | inode_unlock(inode); |
3c446b3d PZ |
5809 | |
5810 | if (retval < 0) | |
5811 | return retval; | |
5812 | ||
5813 | return 0; | |
5814 | } | |
5815 | ||
0793a61d | 5816 | static const struct file_operations perf_fops = { |
3326c1ce | 5817 | .llseek = no_llseek, |
0793a61d TG |
5818 | .release = perf_release, |
5819 | .read = perf_read, | |
5820 | .poll = perf_poll, | |
d859e29f | 5821 | .unlocked_ioctl = perf_ioctl, |
b3f20785 | 5822 | .compat_ioctl = perf_compat_ioctl, |
37d81828 | 5823 | .mmap = perf_mmap, |
3c446b3d | 5824 | .fasync = perf_fasync, |
0793a61d TG |
5825 | }; |
5826 | ||
925d519a | 5827 | /* |
cdd6c482 | 5828 | * Perf event wakeup |
925d519a PZ |
5829 | * |
5830 | * If there's data, ensure we set the poll() state and publish everything | |
5831 | * to user-space before waking everybody up. | |
5832 | */ | |
5833 | ||
fed66e2c PZ |
5834 | static inline struct fasync_struct **perf_event_fasync(struct perf_event *event) |
5835 | { | |
5836 | /* only the parent has fasync state */ | |
5837 | if (event->parent) | |
5838 | event = event->parent; | |
5839 | return &event->fasync; | |
5840 | } | |
5841 | ||
cdd6c482 | 5842 | void perf_event_wakeup(struct perf_event *event) |
925d519a | 5843 | { |
10c6db11 | 5844 | ring_buffer_wakeup(event); |
4c9e2542 | 5845 | |
cdd6c482 | 5846 | if (event->pending_kill) { |
fed66e2c | 5847 | kill_fasync(perf_event_fasync(event), SIGIO, event->pending_kill); |
cdd6c482 | 5848 | event->pending_kill = 0; |
4c9e2542 | 5849 | } |
925d519a PZ |
5850 | } |
5851 | ||
1d54ad94 PZ |
5852 | static void perf_pending_event_disable(struct perf_event *event) |
5853 | { | |
5854 | int cpu = READ_ONCE(event->pending_disable); | |
5855 | ||
5856 | if (cpu < 0) | |
5857 | return; | |
5858 | ||
5859 | if (cpu == smp_processor_id()) { | |
5860 | WRITE_ONCE(event->pending_disable, -1); | |
5861 | perf_event_disable_local(event); | |
5862 | return; | |
5863 | } | |
5864 | ||
5865 | /* | |
5866 | * CPU-A CPU-B | |
5867 | * | |
5868 | * perf_event_disable_inatomic() | |
5869 | * @pending_disable = CPU-A; | |
5870 | * irq_work_queue(); | |
5871 | * | |
5872 | * sched-out | |
5873 | * @pending_disable = -1; | |
5874 | * | |
5875 | * sched-in | |
5876 | * perf_event_disable_inatomic() | |
5877 | * @pending_disable = CPU-B; | |
5878 | * irq_work_queue(); // FAILS | |
5879 | * | |
5880 | * irq_work_run() | |
5881 | * perf_pending_event() | |
5882 | * | |
5883 | * But the event runs on CPU-B and wants disabling there. | |
5884 | */ | |
5885 | irq_work_queue_on(&event->pending, cpu); | |
5886 | } | |
5887 | ||
e360adbe | 5888 | static void perf_pending_event(struct irq_work *entry) |
79f14641 | 5889 | { |
1d54ad94 | 5890 | struct perf_event *event = container_of(entry, struct perf_event, pending); |
d525211f PZ |
5891 | int rctx; |
5892 | ||
5893 | rctx = perf_swevent_get_recursion_context(); | |
5894 | /* | |
5895 | * If we 'fail' here, that's OK, it means recursion is already disabled | |
5896 | * and we won't recurse 'further'. | |
5897 | */ | |
79f14641 | 5898 | |
1d54ad94 | 5899 | perf_pending_event_disable(event); |
79f14641 | 5900 | |
cdd6c482 IM |
5901 | if (event->pending_wakeup) { |
5902 | event->pending_wakeup = 0; | |
5903 | perf_event_wakeup(event); | |
79f14641 | 5904 | } |
d525211f PZ |
5905 | |
5906 | if (rctx >= 0) | |
5907 | perf_swevent_put_recursion_context(rctx); | |
79f14641 PZ |
5908 | } |
5909 | ||
39447b38 ZY |
5910 | /* |
5911 | * We assume there is only KVM supporting the callbacks. | |
5912 | * Later on, we might change it to a list if there is | |
5913 | * another virtualization implementation supporting the callbacks. | |
5914 | */ | |
5915 | struct perf_guest_info_callbacks *perf_guest_cbs; | |
5916 | ||
5917 | int perf_register_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
5918 | { | |
5919 | perf_guest_cbs = cbs; | |
5920 | return 0; | |
5921 | } | |
5922 | EXPORT_SYMBOL_GPL(perf_register_guest_info_callbacks); | |
5923 | ||
5924 | int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *cbs) | |
5925 | { | |
5926 | perf_guest_cbs = NULL; | |
5927 | return 0; | |
5928 | } | |
5929 | EXPORT_SYMBOL_GPL(perf_unregister_guest_info_callbacks); | |
5930 | ||
4018994f JO |
5931 | static void |
5932 | perf_output_sample_regs(struct perf_output_handle *handle, | |
5933 | struct pt_regs *regs, u64 mask) | |
5934 | { | |
5935 | int bit; | |
29dd3288 | 5936 | DECLARE_BITMAP(_mask, 64); |
4018994f | 5937 | |
29dd3288 MS |
5938 | bitmap_from_u64(_mask, mask); |
5939 | for_each_set_bit(bit, _mask, sizeof(mask) * BITS_PER_BYTE) { | |
4018994f JO |
5940 | u64 val; |
5941 | ||
5942 | val = perf_reg_value(regs, bit); | |
5943 | perf_output_put(handle, val); | |
5944 | } | |
5945 | } | |
5946 | ||
60e2364e | 5947 | static void perf_sample_regs_user(struct perf_regs *regs_user, |
88a7c26a AL |
5948 | struct pt_regs *regs, |
5949 | struct pt_regs *regs_user_copy) | |
4018994f | 5950 | { |
88a7c26a AL |
5951 | if (user_mode(regs)) { |
5952 | regs_user->abi = perf_reg_abi(current); | |
2565711f | 5953 | regs_user->regs = regs; |
085ebfe9 | 5954 | } else if (!(current->flags & PF_KTHREAD)) { |
88a7c26a | 5955 | perf_get_regs_user(regs_user, regs, regs_user_copy); |
2565711f PZ |
5956 | } else { |
5957 | regs_user->abi = PERF_SAMPLE_REGS_ABI_NONE; | |
5958 | regs_user->regs = NULL; | |
4018994f JO |
5959 | } |
5960 | } | |
5961 | ||
60e2364e SE |
5962 | static void perf_sample_regs_intr(struct perf_regs *regs_intr, |
5963 | struct pt_regs *regs) | |
5964 | { | |
5965 | regs_intr->regs = regs; | |
5966 | regs_intr->abi = perf_reg_abi(current); | |
5967 | } | |
5968 | ||
5969 | ||
c5ebcedb JO |
5970 | /* |
5971 | * Get remaining task size from user stack pointer. | |
5972 | * | |
5973 | * It'd be better to take stack vma map and limit this more | |
5974 | * precisly, but there's no way to get it safely under interrupt, | |
5975 | * so using TASK_SIZE as limit. | |
5976 | */ | |
5977 | static u64 perf_ustack_task_size(struct pt_regs *regs) | |
5978 | { | |
5979 | unsigned long addr = perf_user_stack_pointer(regs); | |
5980 | ||
5981 | if (!addr || addr >= TASK_SIZE) | |
5982 | return 0; | |
5983 | ||
5984 | return TASK_SIZE - addr; | |
5985 | } | |
5986 | ||
5987 | static u16 | |
5988 | perf_sample_ustack_size(u16 stack_size, u16 header_size, | |
5989 | struct pt_regs *regs) | |
5990 | { | |
5991 | u64 task_size; | |
5992 | ||
5993 | /* No regs, no stack pointer, no dump. */ | |
5994 | if (!regs) | |
5995 | return 0; | |
5996 | ||
5997 | /* | |
5998 | * Check if we fit in with the requested stack size into the: | |
5999 | * - TASK_SIZE | |
6000 | * If we don't, we limit the size to the TASK_SIZE. | |
6001 | * | |
6002 | * - remaining sample size | |
6003 | * If we don't, we customize the stack size to | |
6004 | * fit in to the remaining sample size. | |
6005 | */ | |
6006 | ||
6007 | task_size = min((u64) USHRT_MAX, perf_ustack_task_size(regs)); | |
6008 | stack_size = min(stack_size, (u16) task_size); | |
6009 | ||
6010 | /* Current header size plus static size and dynamic size. */ | |
6011 | header_size += 2 * sizeof(u64); | |
6012 | ||
6013 | /* Do we fit in with the current stack dump size? */ | |
6014 | if ((u16) (header_size + stack_size) < header_size) { | |
6015 | /* | |
6016 | * If we overflow the maximum size for the sample, | |
6017 | * we customize the stack dump size to fit in. | |
6018 | */ | |
6019 | stack_size = USHRT_MAX - header_size - sizeof(u64); | |
6020 | stack_size = round_up(stack_size, sizeof(u64)); | |
6021 | } | |
6022 | ||
6023 | return stack_size; | |
6024 | } | |
6025 | ||
6026 | static void | |
6027 | perf_output_sample_ustack(struct perf_output_handle *handle, u64 dump_size, | |
6028 | struct pt_regs *regs) | |
6029 | { | |
6030 | /* Case of a kernel thread, nothing to dump */ | |
6031 | if (!regs) { | |
6032 | u64 size = 0; | |
6033 | perf_output_put(handle, size); | |
6034 | } else { | |
6035 | unsigned long sp; | |
6036 | unsigned int rem; | |
6037 | u64 dyn_size; | |
02e18447 | 6038 | mm_segment_t fs; |
c5ebcedb JO |
6039 | |
6040 | /* | |
6041 | * We dump: | |
6042 | * static size | |
6043 | * - the size requested by user or the best one we can fit | |
6044 | * in to the sample max size | |
6045 | * data | |
6046 | * - user stack dump data | |
6047 | * dynamic size | |
6048 | * - the actual dumped size | |
6049 | */ | |
6050 | ||
6051 | /* Static size. */ | |
6052 | perf_output_put(handle, dump_size); | |
6053 | ||
6054 | /* Data. */ | |
6055 | sp = perf_user_stack_pointer(regs); | |
02e18447 YC |
6056 | fs = get_fs(); |
6057 | set_fs(USER_DS); | |
c5ebcedb | 6058 | rem = __output_copy_user(handle, (void *) sp, dump_size); |
02e18447 | 6059 | set_fs(fs); |
c5ebcedb JO |
6060 | dyn_size = dump_size - rem; |
6061 | ||
6062 | perf_output_skip(handle, rem); | |
6063 | ||
6064 | /* Dynamic size. */ | |
6065 | perf_output_put(handle, dyn_size); | |
6066 | } | |
6067 | } | |
6068 | ||
c980d109 ACM |
6069 | static void __perf_event_header__init_id(struct perf_event_header *header, |
6070 | struct perf_sample_data *data, | |
6071 | struct perf_event *event) | |
6844c09d ACM |
6072 | { |
6073 | u64 sample_type = event->attr.sample_type; | |
6074 | ||
6075 | data->type = sample_type; | |
6076 | header->size += event->id_header_size; | |
6077 | ||
6078 | if (sample_type & PERF_SAMPLE_TID) { | |
6079 | /* namespace issues */ | |
6080 | data->tid_entry.pid = perf_event_pid(event, current); | |
6081 | data->tid_entry.tid = perf_event_tid(event, current); | |
6082 | } | |
6083 | ||
6084 | if (sample_type & PERF_SAMPLE_TIME) | |
34f43927 | 6085 | data->time = perf_event_clock(event); |
6844c09d | 6086 | |
ff3d527c | 6087 | if (sample_type & (PERF_SAMPLE_ID | PERF_SAMPLE_IDENTIFIER)) |
6844c09d ACM |
6088 | data->id = primary_event_id(event); |
6089 | ||
6090 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6091 | data->stream_id = event->id; | |
6092 | ||
6093 | if (sample_type & PERF_SAMPLE_CPU) { | |
6094 | data->cpu_entry.cpu = raw_smp_processor_id(); | |
6095 | data->cpu_entry.reserved = 0; | |
6096 | } | |
6097 | } | |
6098 | ||
76369139 FW |
6099 | void perf_event_header__init_id(struct perf_event_header *header, |
6100 | struct perf_sample_data *data, | |
6101 | struct perf_event *event) | |
c980d109 ACM |
6102 | { |
6103 | if (event->attr.sample_id_all) | |
6104 | __perf_event_header__init_id(header, data, event); | |
6105 | } | |
6106 | ||
6107 | static void __perf_event__output_id_sample(struct perf_output_handle *handle, | |
6108 | struct perf_sample_data *data) | |
6109 | { | |
6110 | u64 sample_type = data->type; | |
6111 | ||
6112 | if (sample_type & PERF_SAMPLE_TID) | |
6113 | perf_output_put(handle, data->tid_entry); | |
6114 | ||
6115 | if (sample_type & PERF_SAMPLE_TIME) | |
6116 | perf_output_put(handle, data->time); | |
6117 | ||
6118 | if (sample_type & PERF_SAMPLE_ID) | |
6119 | perf_output_put(handle, data->id); | |
6120 | ||
6121 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6122 | perf_output_put(handle, data->stream_id); | |
6123 | ||
6124 | if (sample_type & PERF_SAMPLE_CPU) | |
6125 | perf_output_put(handle, data->cpu_entry); | |
ff3d527c AH |
6126 | |
6127 | if (sample_type & PERF_SAMPLE_IDENTIFIER) | |
6128 | perf_output_put(handle, data->id); | |
c980d109 ACM |
6129 | } |
6130 | ||
76369139 FW |
6131 | void perf_event__output_id_sample(struct perf_event *event, |
6132 | struct perf_output_handle *handle, | |
6133 | struct perf_sample_data *sample) | |
c980d109 ACM |
6134 | { |
6135 | if (event->attr.sample_id_all) | |
6136 | __perf_event__output_id_sample(handle, sample); | |
6137 | } | |
6138 | ||
3dab77fb | 6139 | static void perf_output_read_one(struct perf_output_handle *handle, |
eed01528 SE |
6140 | struct perf_event *event, |
6141 | u64 enabled, u64 running) | |
3dab77fb | 6142 | { |
cdd6c482 | 6143 | u64 read_format = event->attr.read_format; |
3dab77fb PZ |
6144 | u64 values[4]; |
6145 | int n = 0; | |
6146 | ||
b5e58793 | 6147 | values[n++] = perf_event_count(event); |
3dab77fb | 6148 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { |
eed01528 | 6149 | values[n++] = enabled + |
cdd6c482 | 6150 | atomic64_read(&event->child_total_time_enabled); |
3dab77fb PZ |
6151 | } |
6152 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { | |
eed01528 | 6153 | values[n++] = running + |
cdd6c482 | 6154 | atomic64_read(&event->child_total_time_running); |
3dab77fb PZ |
6155 | } |
6156 | if (read_format & PERF_FORMAT_ID) | |
cdd6c482 | 6157 | values[n++] = primary_event_id(event); |
3dab77fb | 6158 | |
76369139 | 6159 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
6160 | } |
6161 | ||
3dab77fb | 6162 | static void perf_output_read_group(struct perf_output_handle *handle, |
eed01528 SE |
6163 | struct perf_event *event, |
6164 | u64 enabled, u64 running) | |
3dab77fb | 6165 | { |
cdd6c482 IM |
6166 | struct perf_event *leader = event->group_leader, *sub; |
6167 | u64 read_format = event->attr.read_format; | |
3dab77fb PZ |
6168 | u64 values[5]; |
6169 | int n = 0; | |
6170 | ||
6171 | values[n++] = 1 + leader->nr_siblings; | |
6172 | ||
6173 | if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) | |
eed01528 | 6174 | values[n++] = enabled; |
3dab77fb PZ |
6175 | |
6176 | if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) | |
eed01528 | 6177 | values[n++] = running; |
3dab77fb | 6178 | |
9e5b127d PZ |
6179 | if ((leader != event) && |
6180 | (leader->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
6181 | leader->pmu->read(leader); |
6182 | ||
b5e58793 | 6183 | values[n++] = perf_event_count(leader); |
3dab77fb | 6184 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 6185 | values[n++] = primary_event_id(leader); |
3dab77fb | 6186 | |
76369139 | 6187 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb | 6188 | |
edb39592 | 6189 | for_each_sibling_event(sub, leader) { |
3dab77fb PZ |
6190 | n = 0; |
6191 | ||
6f5ab001 JO |
6192 | if ((sub != event) && |
6193 | (sub->state == PERF_EVENT_STATE_ACTIVE)) | |
3dab77fb PZ |
6194 | sub->pmu->read(sub); |
6195 | ||
b5e58793 | 6196 | values[n++] = perf_event_count(sub); |
3dab77fb | 6197 | if (read_format & PERF_FORMAT_ID) |
cdd6c482 | 6198 | values[n++] = primary_event_id(sub); |
3dab77fb | 6199 | |
76369139 | 6200 | __output_copy(handle, values, n * sizeof(u64)); |
3dab77fb PZ |
6201 | } |
6202 | } | |
6203 | ||
eed01528 SE |
6204 | #define PERF_FORMAT_TOTAL_TIMES (PERF_FORMAT_TOTAL_TIME_ENABLED|\ |
6205 | PERF_FORMAT_TOTAL_TIME_RUNNING) | |
6206 | ||
ba5213ae PZ |
6207 | /* |
6208 | * XXX PERF_SAMPLE_READ vs inherited events seems difficult. | |
6209 | * | |
6210 | * The problem is that its both hard and excessively expensive to iterate the | |
6211 | * child list, not to mention that its impossible to IPI the children running | |
6212 | * on another CPU, from interrupt/NMI context. | |
6213 | */ | |
3dab77fb | 6214 | static void perf_output_read(struct perf_output_handle *handle, |
cdd6c482 | 6215 | struct perf_event *event) |
3dab77fb | 6216 | { |
e3f3541c | 6217 | u64 enabled = 0, running = 0, now; |
eed01528 SE |
6218 | u64 read_format = event->attr.read_format; |
6219 | ||
6220 | /* | |
6221 | * compute total_time_enabled, total_time_running | |
6222 | * based on snapshot values taken when the event | |
6223 | * was last scheduled in. | |
6224 | * | |
6225 | * we cannot simply called update_context_time() | |
6226 | * because of locking issue as we are called in | |
6227 | * NMI context | |
6228 | */ | |
c4794295 | 6229 | if (read_format & PERF_FORMAT_TOTAL_TIMES) |
e3f3541c | 6230 | calc_timer_values(event, &now, &enabled, &running); |
eed01528 | 6231 | |
cdd6c482 | 6232 | if (event->attr.read_format & PERF_FORMAT_GROUP) |
eed01528 | 6233 | perf_output_read_group(handle, event, enabled, running); |
3dab77fb | 6234 | else |
eed01528 | 6235 | perf_output_read_one(handle, event, enabled, running); |
3dab77fb PZ |
6236 | } |
6237 | ||
5622f295 MM |
6238 | void perf_output_sample(struct perf_output_handle *handle, |
6239 | struct perf_event_header *header, | |
6240 | struct perf_sample_data *data, | |
cdd6c482 | 6241 | struct perf_event *event) |
5622f295 MM |
6242 | { |
6243 | u64 sample_type = data->type; | |
6244 | ||
6245 | perf_output_put(handle, *header); | |
6246 | ||
ff3d527c AH |
6247 | if (sample_type & PERF_SAMPLE_IDENTIFIER) |
6248 | perf_output_put(handle, data->id); | |
6249 | ||
5622f295 MM |
6250 | if (sample_type & PERF_SAMPLE_IP) |
6251 | perf_output_put(handle, data->ip); | |
6252 | ||
6253 | if (sample_type & PERF_SAMPLE_TID) | |
6254 | perf_output_put(handle, data->tid_entry); | |
6255 | ||
6256 | if (sample_type & PERF_SAMPLE_TIME) | |
6257 | perf_output_put(handle, data->time); | |
6258 | ||
6259 | if (sample_type & PERF_SAMPLE_ADDR) | |
6260 | perf_output_put(handle, data->addr); | |
6261 | ||
6262 | if (sample_type & PERF_SAMPLE_ID) | |
6263 | perf_output_put(handle, data->id); | |
6264 | ||
6265 | if (sample_type & PERF_SAMPLE_STREAM_ID) | |
6266 | perf_output_put(handle, data->stream_id); | |
6267 | ||
6268 | if (sample_type & PERF_SAMPLE_CPU) | |
6269 | perf_output_put(handle, data->cpu_entry); | |
6270 | ||
6271 | if (sample_type & PERF_SAMPLE_PERIOD) | |
6272 | perf_output_put(handle, data->period); | |
6273 | ||
6274 | if (sample_type & PERF_SAMPLE_READ) | |
cdd6c482 | 6275 | perf_output_read(handle, event); |
5622f295 MM |
6276 | |
6277 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { | |
99e818cc | 6278 | int size = 1; |
5622f295 | 6279 | |
99e818cc JO |
6280 | size += data->callchain->nr; |
6281 | size *= sizeof(u64); | |
6282 | __output_copy(handle, data->callchain, size); | |
5622f295 MM |
6283 | } |
6284 | ||
6285 | if (sample_type & PERF_SAMPLE_RAW) { | |
7e3f977e DB |
6286 | struct perf_raw_record *raw = data->raw; |
6287 | ||
6288 | if (raw) { | |
6289 | struct perf_raw_frag *frag = &raw->frag; | |
6290 | ||
6291 | perf_output_put(handle, raw->size); | |
6292 | do { | |
6293 | if (frag->copy) { | |
6294 | __output_custom(handle, frag->copy, | |
6295 | frag->data, frag->size); | |
6296 | } else { | |
6297 | __output_copy(handle, frag->data, | |
6298 | frag->size); | |
6299 | } | |
6300 | if (perf_raw_frag_last(frag)) | |
6301 | break; | |
6302 | frag = frag->next; | |
6303 | } while (1); | |
6304 | if (frag->pad) | |
6305 | __output_skip(handle, NULL, frag->pad); | |
5622f295 MM |
6306 | } else { |
6307 | struct { | |
6308 | u32 size; | |
6309 | u32 data; | |
6310 | } raw = { | |
6311 | .size = sizeof(u32), | |
6312 | .data = 0, | |
6313 | }; | |
6314 | perf_output_put(handle, raw); | |
6315 | } | |
6316 | } | |
a7ac67ea | 6317 | |
bce38cd5 SE |
6318 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { |
6319 | if (data->br_stack) { | |
6320 | size_t size; | |
6321 | ||
6322 | size = data->br_stack->nr | |
6323 | * sizeof(struct perf_branch_entry); | |
6324 | ||
6325 | perf_output_put(handle, data->br_stack->nr); | |
6326 | perf_output_copy(handle, data->br_stack->entries, size); | |
6327 | } else { | |
6328 | /* | |
6329 | * we always store at least the value of nr | |
6330 | */ | |
6331 | u64 nr = 0; | |
6332 | perf_output_put(handle, nr); | |
6333 | } | |
6334 | } | |
4018994f JO |
6335 | |
6336 | if (sample_type & PERF_SAMPLE_REGS_USER) { | |
6337 | u64 abi = data->regs_user.abi; | |
6338 | ||
6339 | /* | |
6340 | * If there are no regs to dump, notice it through | |
6341 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
6342 | */ | |
6343 | perf_output_put(handle, abi); | |
6344 | ||
6345 | if (abi) { | |
6346 | u64 mask = event->attr.sample_regs_user; | |
6347 | perf_output_sample_regs(handle, | |
6348 | data->regs_user.regs, | |
6349 | mask); | |
6350 | } | |
6351 | } | |
c5ebcedb | 6352 | |
a5cdd40c | 6353 | if (sample_type & PERF_SAMPLE_STACK_USER) { |
c5ebcedb JO |
6354 | perf_output_sample_ustack(handle, |
6355 | data->stack_user_size, | |
6356 | data->regs_user.regs); | |
a5cdd40c | 6357 | } |
c3feedf2 AK |
6358 | |
6359 | if (sample_type & PERF_SAMPLE_WEIGHT) | |
6360 | perf_output_put(handle, data->weight); | |
d6be9ad6 SE |
6361 | |
6362 | if (sample_type & PERF_SAMPLE_DATA_SRC) | |
6363 | perf_output_put(handle, data->data_src.val); | |
a5cdd40c | 6364 | |
fdfbbd07 AK |
6365 | if (sample_type & PERF_SAMPLE_TRANSACTION) |
6366 | perf_output_put(handle, data->txn); | |
6367 | ||
60e2364e SE |
6368 | if (sample_type & PERF_SAMPLE_REGS_INTR) { |
6369 | u64 abi = data->regs_intr.abi; | |
6370 | /* | |
6371 | * If there are no regs to dump, notice it through | |
6372 | * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE). | |
6373 | */ | |
6374 | perf_output_put(handle, abi); | |
6375 | ||
6376 | if (abi) { | |
6377 | u64 mask = event->attr.sample_regs_intr; | |
6378 | ||
6379 | perf_output_sample_regs(handle, | |
6380 | data->regs_intr.regs, | |
6381 | mask); | |
6382 | } | |
6383 | } | |
6384 | ||
fc7ce9c7 KL |
6385 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) |
6386 | perf_output_put(handle, data->phys_addr); | |
6387 | ||
a5cdd40c PZ |
6388 | if (!event->attr.watermark) { |
6389 | int wakeup_events = event->attr.wakeup_events; | |
6390 | ||
6391 | if (wakeup_events) { | |
6392 | struct ring_buffer *rb = handle->rb; | |
6393 | int events = local_inc_return(&rb->events); | |
6394 | ||
6395 | if (events >= wakeup_events) { | |
6396 | local_sub(wakeup_events, &rb->events); | |
6397 | local_inc(&rb->wakeup); | |
6398 | } | |
6399 | } | |
6400 | } | |
5622f295 MM |
6401 | } |
6402 | ||
fc7ce9c7 KL |
6403 | static u64 perf_virt_to_phys(u64 virt) |
6404 | { | |
6405 | u64 phys_addr = 0; | |
6406 | struct page *p = NULL; | |
6407 | ||
6408 | if (!virt) | |
6409 | return 0; | |
6410 | ||
6411 | if (virt >= TASK_SIZE) { | |
6412 | /* If it's vmalloc()d memory, leave phys_addr as 0 */ | |
6413 | if (virt_addr_valid((void *)(uintptr_t)virt) && | |
6414 | !(virt >= VMALLOC_START && virt < VMALLOC_END)) | |
6415 | phys_addr = (u64)virt_to_phys((void *)(uintptr_t)virt); | |
6416 | } else { | |
6417 | /* | |
6418 | * Walking the pages tables for user address. | |
6419 | * Interrupts are disabled, so it prevents any tear down | |
6420 | * of the page tables. | |
6421 | * Try IRQ-safe __get_user_pages_fast first. | |
6422 | * If failed, leave phys_addr as 0. | |
6423 | */ | |
6424 | if ((current->mm != NULL) && | |
6425 | (__get_user_pages_fast(virt, 1, 0, &p) == 1)) | |
6426 | phys_addr = page_to_phys(p) + virt % PAGE_SIZE; | |
6427 | ||
6428 | if (p) | |
6429 | put_page(p); | |
6430 | } | |
6431 | ||
6432 | return phys_addr; | |
6433 | } | |
6434 | ||
99e818cc JO |
6435 | static struct perf_callchain_entry __empty_callchain = { .nr = 0, }; |
6436 | ||
6cbc304f | 6437 | struct perf_callchain_entry * |
8cf7e0e2 JO |
6438 | perf_callchain(struct perf_event *event, struct pt_regs *regs) |
6439 | { | |
6440 | bool kernel = !event->attr.exclude_callchain_kernel; | |
6441 | bool user = !event->attr.exclude_callchain_user; | |
6442 | /* Disallow cross-task user callchains. */ | |
6443 | bool crosstask = event->ctx->task && event->ctx->task != current; | |
6444 | const u32 max_stack = event->attr.sample_max_stack; | |
99e818cc | 6445 | struct perf_callchain_entry *callchain; |
8cf7e0e2 JO |
6446 | |
6447 | if (!kernel && !user) | |
99e818cc | 6448 | return &__empty_callchain; |
8cf7e0e2 | 6449 | |
99e818cc JO |
6450 | callchain = get_perf_callchain(regs, 0, kernel, user, |
6451 | max_stack, crosstask, true); | |
6452 | return callchain ?: &__empty_callchain; | |
8cf7e0e2 JO |
6453 | } |
6454 | ||
5622f295 MM |
6455 | void perf_prepare_sample(struct perf_event_header *header, |
6456 | struct perf_sample_data *data, | |
cdd6c482 | 6457 | struct perf_event *event, |
5622f295 | 6458 | struct pt_regs *regs) |
7b732a75 | 6459 | { |
cdd6c482 | 6460 | u64 sample_type = event->attr.sample_type; |
7b732a75 | 6461 | |
cdd6c482 | 6462 | header->type = PERF_RECORD_SAMPLE; |
c320c7b7 | 6463 | header->size = sizeof(*header) + event->header_size; |
5622f295 MM |
6464 | |
6465 | header->misc = 0; | |
6466 | header->misc |= perf_misc_flags(regs); | |
6fab0192 | 6467 | |
c980d109 | 6468 | __perf_event_header__init_id(header, data, event); |
6844c09d | 6469 | |
c320c7b7 | 6470 | if (sample_type & PERF_SAMPLE_IP) |
5622f295 MM |
6471 | data->ip = perf_instruction_pointer(regs); |
6472 | ||
b23f3325 | 6473 | if (sample_type & PERF_SAMPLE_CALLCHAIN) { |
5622f295 | 6474 | int size = 1; |
394ee076 | 6475 | |
6cbc304f PZ |
6476 | if (!(sample_type & __PERF_SAMPLE_CALLCHAIN_EARLY)) |
6477 | data->callchain = perf_callchain(event, regs); | |
6478 | ||
99e818cc | 6479 | size += data->callchain->nr; |
5622f295 MM |
6480 | |
6481 | header->size += size * sizeof(u64); | |
394ee076 PZ |
6482 | } |
6483 | ||
3a43ce68 | 6484 | if (sample_type & PERF_SAMPLE_RAW) { |
7e3f977e DB |
6485 | struct perf_raw_record *raw = data->raw; |
6486 | int size; | |
6487 | ||
6488 | if (raw) { | |
6489 | struct perf_raw_frag *frag = &raw->frag; | |
6490 | u32 sum = 0; | |
6491 | ||
6492 | do { | |
6493 | sum += frag->size; | |
6494 | if (perf_raw_frag_last(frag)) | |
6495 | break; | |
6496 | frag = frag->next; | |
6497 | } while (1); | |
6498 | ||
6499 | size = round_up(sum + sizeof(u32), sizeof(u64)); | |
6500 | raw->size = size - sizeof(u32); | |
6501 | frag->pad = raw->size - sum; | |
6502 | } else { | |
6503 | size = sizeof(u64); | |
6504 | } | |
a044560c | 6505 | |
7e3f977e | 6506 | header->size += size; |
7f453c24 | 6507 | } |
bce38cd5 SE |
6508 | |
6509 | if (sample_type & PERF_SAMPLE_BRANCH_STACK) { | |
6510 | int size = sizeof(u64); /* nr */ | |
6511 | if (data->br_stack) { | |
6512 | size += data->br_stack->nr | |
6513 | * sizeof(struct perf_branch_entry); | |
6514 | } | |
6515 | header->size += size; | |
6516 | } | |
4018994f | 6517 | |
2565711f | 6518 | if (sample_type & (PERF_SAMPLE_REGS_USER | PERF_SAMPLE_STACK_USER)) |
88a7c26a AL |
6519 | perf_sample_regs_user(&data->regs_user, regs, |
6520 | &data->regs_user_copy); | |
2565711f | 6521 | |
4018994f JO |
6522 | if (sample_type & PERF_SAMPLE_REGS_USER) { |
6523 | /* regs dump ABI info */ | |
6524 | int size = sizeof(u64); | |
6525 | ||
4018994f JO |
6526 | if (data->regs_user.regs) { |
6527 | u64 mask = event->attr.sample_regs_user; | |
6528 | size += hweight64(mask) * sizeof(u64); | |
6529 | } | |
6530 | ||
6531 | header->size += size; | |
6532 | } | |
c5ebcedb JO |
6533 | |
6534 | if (sample_type & PERF_SAMPLE_STACK_USER) { | |
6535 | /* | |
6536 | * Either we need PERF_SAMPLE_STACK_USER bit to be allways | |
6537 | * processed as the last one or have additional check added | |
6538 | * in case new sample type is added, because we could eat | |
6539 | * up the rest of the sample size. | |
6540 | */ | |
c5ebcedb JO |
6541 | u16 stack_size = event->attr.sample_stack_user; |
6542 | u16 size = sizeof(u64); | |
6543 | ||
c5ebcedb | 6544 | stack_size = perf_sample_ustack_size(stack_size, header->size, |
2565711f | 6545 | data->regs_user.regs); |
c5ebcedb JO |
6546 | |
6547 | /* | |
6548 | * If there is something to dump, add space for the dump | |
6549 | * itself and for the field that tells the dynamic size, | |
6550 | * which is how many have been actually dumped. | |
6551 | */ | |
6552 | if (stack_size) | |
6553 | size += sizeof(u64) + stack_size; | |
6554 | ||
6555 | data->stack_user_size = stack_size; | |
6556 | header->size += size; | |
6557 | } | |
60e2364e SE |
6558 | |
6559 | if (sample_type & PERF_SAMPLE_REGS_INTR) { | |
6560 | /* regs dump ABI info */ | |
6561 | int size = sizeof(u64); | |
6562 | ||
6563 | perf_sample_regs_intr(&data->regs_intr, regs); | |
6564 | ||
6565 | if (data->regs_intr.regs) { | |
6566 | u64 mask = event->attr.sample_regs_intr; | |
6567 | ||
6568 | size += hweight64(mask) * sizeof(u64); | |
6569 | } | |
6570 | ||
6571 | header->size += size; | |
6572 | } | |
fc7ce9c7 KL |
6573 | |
6574 | if (sample_type & PERF_SAMPLE_PHYS_ADDR) | |
6575 | data->phys_addr = perf_virt_to_phys(data->addr); | |
5622f295 | 6576 | } |
7f453c24 | 6577 | |
56201969 | 6578 | static __always_inline int |
9ecda41a WN |
6579 | __perf_event_output(struct perf_event *event, |
6580 | struct perf_sample_data *data, | |
6581 | struct pt_regs *regs, | |
6582 | int (*output_begin)(struct perf_output_handle *, | |
6583 | struct perf_event *, | |
6584 | unsigned int)) | |
5622f295 MM |
6585 | { |
6586 | struct perf_output_handle handle; | |
6587 | struct perf_event_header header; | |
56201969 | 6588 | int err; |
689802b2 | 6589 | |
927c7a9e FW |
6590 | /* protect the callchain buffers */ |
6591 | rcu_read_lock(); | |
6592 | ||
cdd6c482 | 6593 | perf_prepare_sample(&header, data, event, regs); |
5c148194 | 6594 | |
56201969 ACM |
6595 | err = output_begin(&handle, event, header.size); |
6596 | if (err) | |
927c7a9e | 6597 | goto exit; |
0322cd6e | 6598 | |
cdd6c482 | 6599 | perf_output_sample(&handle, &header, data, event); |
f413cdb8 | 6600 | |
8a057d84 | 6601 | perf_output_end(&handle); |
927c7a9e FW |
6602 | |
6603 | exit: | |
6604 | rcu_read_unlock(); | |
56201969 | 6605 | return err; |
0322cd6e PZ |
6606 | } |
6607 | ||
9ecda41a WN |
6608 | void |
6609 | perf_event_output_forward(struct perf_event *event, | |
6610 | struct perf_sample_data *data, | |
6611 | struct pt_regs *regs) | |
6612 | { | |
6613 | __perf_event_output(event, data, regs, perf_output_begin_forward); | |
6614 | } | |
6615 | ||
6616 | void | |
6617 | perf_event_output_backward(struct perf_event *event, | |
6618 | struct perf_sample_data *data, | |
6619 | struct pt_regs *regs) | |
6620 | { | |
6621 | __perf_event_output(event, data, regs, perf_output_begin_backward); | |
6622 | } | |
6623 | ||
56201969 | 6624 | int |
9ecda41a WN |
6625 | perf_event_output(struct perf_event *event, |
6626 | struct perf_sample_data *data, | |
6627 | struct pt_regs *regs) | |
6628 | { | |
56201969 | 6629 | return __perf_event_output(event, data, regs, perf_output_begin); |
9ecda41a WN |
6630 | } |
6631 | ||
38b200d6 | 6632 | /* |
cdd6c482 | 6633 | * read event_id |
38b200d6 PZ |
6634 | */ |
6635 | ||
6636 | struct perf_read_event { | |
6637 | struct perf_event_header header; | |
6638 | ||
6639 | u32 pid; | |
6640 | u32 tid; | |
38b200d6 PZ |
6641 | }; |
6642 | ||
6643 | static void | |
cdd6c482 | 6644 | perf_event_read_event(struct perf_event *event, |
38b200d6 PZ |
6645 | struct task_struct *task) |
6646 | { | |
6647 | struct perf_output_handle handle; | |
c980d109 | 6648 | struct perf_sample_data sample; |
dfc65094 | 6649 | struct perf_read_event read_event = { |
38b200d6 | 6650 | .header = { |
cdd6c482 | 6651 | .type = PERF_RECORD_READ, |
38b200d6 | 6652 | .misc = 0, |
c320c7b7 | 6653 | .size = sizeof(read_event) + event->read_size, |
38b200d6 | 6654 | }, |
cdd6c482 IM |
6655 | .pid = perf_event_pid(event, task), |
6656 | .tid = perf_event_tid(event, task), | |
38b200d6 | 6657 | }; |
3dab77fb | 6658 | int ret; |
38b200d6 | 6659 | |
c980d109 | 6660 | perf_event_header__init_id(&read_event.header, &sample, event); |
a7ac67ea | 6661 | ret = perf_output_begin(&handle, event, read_event.header.size); |
38b200d6 PZ |
6662 | if (ret) |
6663 | return; | |
6664 | ||
dfc65094 | 6665 | perf_output_put(&handle, read_event); |
cdd6c482 | 6666 | perf_output_read(&handle, event); |
c980d109 | 6667 | perf_event__output_id_sample(event, &handle, &sample); |
3dab77fb | 6668 | |
38b200d6 PZ |
6669 | perf_output_end(&handle); |
6670 | } | |
6671 | ||
aab5b71e | 6672 | typedef void (perf_iterate_f)(struct perf_event *event, void *data); |
52d857a8 JO |
6673 | |
6674 | static void | |
aab5b71e PZ |
6675 | perf_iterate_ctx(struct perf_event_context *ctx, |
6676 | perf_iterate_f output, | |
b73e4fef | 6677 | void *data, bool all) |
52d857a8 JO |
6678 | { |
6679 | struct perf_event *event; | |
6680 | ||
6681 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
b73e4fef AS |
6682 | if (!all) { |
6683 | if (event->state < PERF_EVENT_STATE_INACTIVE) | |
6684 | continue; | |
6685 | if (!event_filter_match(event)) | |
6686 | continue; | |
6687 | } | |
6688 | ||
67516844 | 6689 | output(event, data); |
52d857a8 JO |
6690 | } |
6691 | } | |
6692 | ||
aab5b71e | 6693 | static void perf_iterate_sb_cpu(perf_iterate_f output, void *data) |
f2fb6bef KL |
6694 | { |
6695 | struct pmu_event_list *pel = this_cpu_ptr(&pmu_sb_events); | |
6696 | struct perf_event *event; | |
6697 | ||
6698 | list_for_each_entry_rcu(event, &pel->list, sb_list) { | |
0b8f1e2e PZ |
6699 | /* |
6700 | * Skip events that are not fully formed yet; ensure that | |
6701 | * if we observe event->ctx, both event and ctx will be | |
6702 | * complete enough. See perf_install_in_context(). | |
6703 | */ | |
6704 | if (!smp_load_acquire(&event->ctx)) | |
6705 | continue; | |
6706 | ||
f2fb6bef KL |
6707 | if (event->state < PERF_EVENT_STATE_INACTIVE) |
6708 | continue; | |
6709 | if (!event_filter_match(event)) | |
6710 | continue; | |
6711 | output(event, data); | |
6712 | } | |
6713 | } | |
6714 | ||
aab5b71e PZ |
6715 | /* |
6716 | * Iterate all events that need to receive side-band events. | |
6717 | * | |
6718 | * For new callers; ensure that account_pmu_sb_event() includes | |
6719 | * your event, otherwise it might not get delivered. | |
6720 | */ | |
52d857a8 | 6721 | static void |
aab5b71e | 6722 | perf_iterate_sb(perf_iterate_f output, void *data, |
52d857a8 JO |
6723 | struct perf_event_context *task_ctx) |
6724 | { | |
52d857a8 | 6725 | struct perf_event_context *ctx; |
52d857a8 JO |
6726 | int ctxn; |
6727 | ||
aab5b71e PZ |
6728 | rcu_read_lock(); |
6729 | preempt_disable(); | |
6730 | ||
4e93ad60 | 6731 | /* |
aab5b71e PZ |
6732 | * If we have task_ctx != NULL we only notify the task context itself. |
6733 | * The task_ctx is set only for EXIT events before releasing task | |
4e93ad60 JO |
6734 | * context. |
6735 | */ | |
6736 | if (task_ctx) { | |
aab5b71e PZ |
6737 | perf_iterate_ctx(task_ctx, output, data, false); |
6738 | goto done; | |
4e93ad60 JO |
6739 | } |
6740 | ||
aab5b71e | 6741 | perf_iterate_sb_cpu(output, data); |
f2fb6bef KL |
6742 | |
6743 | for_each_task_context_nr(ctxn) { | |
52d857a8 JO |
6744 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); |
6745 | if (ctx) | |
aab5b71e | 6746 | perf_iterate_ctx(ctx, output, data, false); |
52d857a8 | 6747 | } |
aab5b71e | 6748 | done: |
f2fb6bef | 6749 | preempt_enable(); |
52d857a8 | 6750 | rcu_read_unlock(); |
95ff4ca2 AS |
6751 | } |
6752 | ||
375637bc AS |
6753 | /* |
6754 | * Clear all file-based filters at exec, they'll have to be | |
6755 | * re-instated when/if these objects are mmapped again. | |
6756 | */ | |
6757 | static void perf_event_addr_filters_exec(struct perf_event *event, void *data) | |
6758 | { | |
6759 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
6760 | struct perf_addr_filter *filter; | |
6761 | unsigned int restart = 0, count = 0; | |
6762 | unsigned long flags; | |
6763 | ||
6764 | if (!has_addr_filter(event)) | |
6765 | return; | |
6766 | ||
6767 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
6768 | list_for_each_entry(filter, &ifh->list, entry) { | |
9511bce9 | 6769 | if (filter->path.dentry) { |
c60f83b8 AS |
6770 | event->addr_filter_ranges[count].start = 0; |
6771 | event->addr_filter_ranges[count].size = 0; | |
375637bc AS |
6772 | restart++; |
6773 | } | |
6774 | ||
6775 | count++; | |
6776 | } | |
6777 | ||
6778 | if (restart) | |
6779 | event->addr_filters_gen++; | |
6780 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
6781 | ||
6782 | if (restart) | |
767ae086 | 6783 | perf_event_stop(event, 1); |
375637bc AS |
6784 | } |
6785 | ||
6786 | void perf_event_exec(void) | |
6787 | { | |
6788 | struct perf_event_context *ctx; | |
6789 | int ctxn; | |
6790 | ||
6791 | rcu_read_lock(); | |
6792 | for_each_task_context_nr(ctxn) { | |
6793 | ctx = current->perf_event_ctxp[ctxn]; | |
6794 | if (!ctx) | |
6795 | continue; | |
6796 | ||
6797 | perf_event_enable_on_exec(ctxn); | |
6798 | ||
aab5b71e | 6799 | perf_iterate_ctx(ctx, perf_event_addr_filters_exec, NULL, |
375637bc AS |
6800 | true); |
6801 | } | |
6802 | rcu_read_unlock(); | |
6803 | } | |
6804 | ||
95ff4ca2 AS |
6805 | struct remote_output { |
6806 | struct ring_buffer *rb; | |
6807 | int err; | |
6808 | }; | |
6809 | ||
6810 | static void __perf_event_output_stop(struct perf_event *event, void *data) | |
6811 | { | |
6812 | struct perf_event *parent = event->parent; | |
6813 | struct remote_output *ro = data; | |
6814 | struct ring_buffer *rb = ro->rb; | |
375637bc AS |
6815 | struct stop_event_data sd = { |
6816 | .event = event, | |
6817 | }; | |
95ff4ca2 AS |
6818 | |
6819 | if (!has_aux(event)) | |
6820 | return; | |
6821 | ||
6822 | if (!parent) | |
6823 | parent = event; | |
6824 | ||
6825 | /* | |
6826 | * In case of inheritance, it will be the parent that links to the | |
767ae086 AS |
6827 | * ring-buffer, but it will be the child that's actually using it. |
6828 | * | |
6829 | * We are using event::rb to determine if the event should be stopped, | |
6830 | * however this may race with ring_buffer_attach() (through set_output), | |
6831 | * which will make us skip the event that actually needs to be stopped. | |
6832 | * So ring_buffer_attach() has to stop an aux event before re-assigning | |
6833 | * its rb pointer. | |
95ff4ca2 AS |
6834 | */ |
6835 | if (rcu_dereference(parent->rb) == rb) | |
375637bc | 6836 | ro->err = __perf_event_stop(&sd); |
95ff4ca2 AS |
6837 | } |
6838 | ||
6839 | static int __perf_pmu_output_stop(void *info) | |
6840 | { | |
6841 | struct perf_event *event = info; | |
6842 | struct pmu *pmu = event->pmu; | |
8b6a3fe8 | 6843 | struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context); |
95ff4ca2 AS |
6844 | struct remote_output ro = { |
6845 | .rb = event->rb, | |
6846 | }; | |
6847 | ||
6848 | rcu_read_lock(); | |
aab5b71e | 6849 | perf_iterate_ctx(&cpuctx->ctx, __perf_event_output_stop, &ro, false); |
95ff4ca2 | 6850 | if (cpuctx->task_ctx) |
aab5b71e | 6851 | perf_iterate_ctx(cpuctx->task_ctx, __perf_event_output_stop, |
b73e4fef | 6852 | &ro, false); |
95ff4ca2 AS |
6853 | rcu_read_unlock(); |
6854 | ||
6855 | return ro.err; | |
6856 | } | |
6857 | ||
6858 | static void perf_pmu_output_stop(struct perf_event *event) | |
6859 | { | |
6860 | struct perf_event *iter; | |
6861 | int err, cpu; | |
6862 | ||
6863 | restart: | |
6864 | rcu_read_lock(); | |
6865 | list_for_each_entry_rcu(iter, &event->rb->event_list, rb_entry) { | |
6866 | /* | |
6867 | * For per-CPU events, we need to make sure that neither they | |
6868 | * nor their children are running; for cpu==-1 events it's | |
6869 | * sufficient to stop the event itself if it's active, since | |
6870 | * it can't have children. | |
6871 | */ | |
6872 | cpu = iter->cpu; | |
6873 | if (cpu == -1) | |
6874 | cpu = READ_ONCE(iter->oncpu); | |
6875 | ||
6876 | if (cpu == -1) | |
6877 | continue; | |
6878 | ||
6879 | err = cpu_function_call(cpu, __perf_pmu_output_stop, event); | |
6880 | if (err == -EAGAIN) { | |
6881 | rcu_read_unlock(); | |
6882 | goto restart; | |
6883 | } | |
6884 | } | |
6885 | rcu_read_unlock(); | |
52d857a8 JO |
6886 | } |
6887 | ||
60313ebe | 6888 | /* |
9f498cc5 PZ |
6889 | * task tracking -- fork/exit |
6890 | * | |
13d7a241 | 6891 | * enabled by: attr.comm | attr.mmap | attr.mmap2 | attr.mmap_data | attr.task |
60313ebe PZ |
6892 | */ |
6893 | ||
9f498cc5 | 6894 | struct perf_task_event { |
3a80b4a3 | 6895 | struct task_struct *task; |
cdd6c482 | 6896 | struct perf_event_context *task_ctx; |
60313ebe PZ |
6897 | |
6898 | struct { | |
6899 | struct perf_event_header header; | |
6900 | ||
6901 | u32 pid; | |
6902 | u32 ppid; | |
9f498cc5 PZ |
6903 | u32 tid; |
6904 | u32 ptid; | |
393b2ad8 | 6905 | u64 time; |
cdd6c482 | 6906 | } event_id; |
60313ebe PZ |
6907 | }; |
6908 | ||
67516844 JO |
6909 | static int perf_event_task_match(struct perf_event *event) |
6910 | { | |
13d7a241 SE |
6911 | return event->attr.comm || event->attr.mmap || |
6912 | event->attr.mmap2 || event->attr.mmap_data || | |
6913 | event->attr.task; | |
67516844 JO |
6914 | } |
6915 | ||
cdd6c482 | 6916 | static void perf_event_task_output(struct perf_event *event, |
52d857a8 | 6917 | void *data) |
60313ebe | 6918 | { |
52d857a8 | 6919 | struct perf_task_event *task_event = data; |
60313ebe | 6920 | struct perf_output_handle handle; |
c980d109 | 6921 | struct perf_sample_data sample; |
9f498cc5 | 6922 | struct task_struct *task = task_event->task; |
c980d109 | 6923 | int ret, size = task_event->event_id.header.size; |
8bb39f9a | 6924 | |
67516844 JO |
6925 | if (!perf_event_task_match(event)) |
6926 | return; | |
6927 | ||
c980d109 | 6928 | perf_event_header__init_id(&task_event->event_id.header, &sample, event); |
60313ebe | 6929 | |
c980d109 | 6930 | ret = perf_output_begin(&handle, event, |
a7ac67ea | 6931 | task_event->event_id.header.size); |
ef60777c | 6932 | if (ret) |
c980d109 | 6933 | goto out; |
60313ebe | 6934 | |
cdd6c482 IM |
6935 | task_event->event_id.pid = perf_event_pid(event, task); |
6936 | task_event->event_id.ppid = perf_event_pid(event, current); | |
60313ebe | 6937 | |
cdd6c482 IM |
6938 | task_event->event_id.tid = perf_event_tid(event, task); |
6939 | task_event->event_id.ptid = perf_event_tid(event, current); | |
9f498cc5 | 6940 | |
34f43927 PZ |
6941 | task_event->event_id.time = perf_event_clock(event); |
6942 | ||
cdd6c482 | 6943 | perf_output_put(&handle, task_event->event_id); |
393b2ad8 | 6944 | |
c980d109 ACM |
6945 | perf_event__output_id_sample(event, &handle, &sample); |
6946 | ||
60313ebe | 6947 | perf_output_end(&handle); |
c980d109 ACM |
6948 | out: |
6949 | task_event->event_id.header.size = size; | |
60313ebe PZ |
6950 | } |
6951 | ||
cdd6c482 IM |
6952 | static void perf_event_task(struct task_struct *task, |
6953 | struct perf_event_context *task_ctx, | |
3a80b4a3 | 6954 | int new) |
60313ebe | 6955 | { |
9f498cc5 | 6956 | struct perf_task_event task_event; |
60313ebe | 6957 | |
cdd6c482 IM |
6958 | if (!atomic_read(&nr_comm_events) && |
6959 | !atomic_read(&nr_mmap_events) && | |
6960 | !atomic_read(&nr_task_events)) | |
60313ebe PZ |
6961 | return; |
6962 | ||
9f498cc5 | 6963 | task_event = (struct perf_task_event){ |
3a80b4a3 PZ |
6964 | .task = task, |
6965 | .task_ctx = task_ctx, | |
cdd6c482 | 6966 | .event_id = { |
60313ebe | 6967 | .header = { |
cdd6c482 | 6968 | .type = new ? PERF_RECORD_FORK : PERF_RECORD_EXIT, |
573402db | 6969 | .misc = 0, |
cdd6c482 | 6970 | .size = sizeof(task_event.event_id), |
60313ebe | 6971 | }, |
573402db PZ |
6972 | /* .pid */ |
6973 | /* .ppid */ | |
9f498cc5 PZ |
6974 | /* .tid */ |
6975 | /* .ptid */ | |
34f43927 | 6976 | /* .time */ |
60313ebe PZ |
6977 | }, |
6978 | }; | |
6979 | ||
aab5b71e | 6980 | perf_iterate_sb(perf_event_task_output, |
52d857a8 JO |
6981 | &task_event, |
6982 | task_ctx); | |
9f498cc5 PZ |
6983 | } |
6984 | ||
cdd6c482 | 6985 | void perf_event_fork(struct task_struct *task) |
9f498cc5 | 6986 | { |
cdd6c482 | 6987 | perf_event_task(task, NULL, 1); |
e4222673 | 6988 | perf_event_namespaces(task); |
60313ebe PZ |
6989 | } |
6990 | ||
8d1b2d93 PZ |
6991 | /* |
6992 | * comm tracking | |
6993 | */ | |
6994 | ||
6995 | struct perf_comm_event { | |
22a4f650 IM |
6996 | struct task_struct *task; |
6997 | char *comm; | |
8d1b2d93 PZ |
6998 | int comm_size; |
6999 | ||
7000 | struct { | |
7001 | struct perf_event_header header; | |
7002 | ||
7003 | u32 pid; | |
7004 | u32 tid; | |
cdd6c482 | 7005 | } event_id; |
8d1b2d93 PZ |
7006 | }; |
7007 | ||
67516844 JO |
7008 | static int perf_event_comm_match(struct perf_event *event) |
7009 | { | |
7010 | return event->attr.comm; | |
7011 | } | |
7012 | ||
cdd6c482 | 7013 | static void perf_event_comm_output(struct perf_event *event, |
52d857a8 | 7014 | void *data) |
8d1b2d93 | 7015 | { |
52d857a8 | 7016 | struct perf_comm_event *comm_event = data; |
8d1b2d93 | 7017 | struct perf_output_handle handle; |
c980d109 | 7018 | struct perf_sample_data sample; |
cdd6c482 | 7019 | int size = comm_event->event_id.header.size; |
c980d109 ACM |
7020 | int ret; |
7021 | ||
67516844 JO |
7022 | if (!perf_event_comm_match(event)) |
7023 | return; | |
7024 | ||
c980d109 ACM |
7025 | perf_event_header__init_id(&comm_event->event_id.header, &sample, event); |
7026 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 7027 | comm_event->event_id.header.size); |
8d1b2d93 PZ |
7028 | |
7029 | if (ret) | |
c980d109 | 7030 | goto out; |
8d1b2d93 | 7031 | |
cdd6c482 IM |
7032 | comm_event->event_id.pid = perf_event_pid(event, comm_event->task); |
7033 | comm_event->event_id.tid = perf_event_tid(event, comm_event->task); | |
709e50cf | 7034 | |
cdd6c482 | 7035 | perf_output_put(&handle, comm_event->event_id); |
76369139 | 7036 | __output_copy(&handle, comm_event->comm, |
8d1b2d93 | 7037 | comm_event->comm_size); |
c980d109 ACM |
7038 | |
7039 | perf_event__output_id_sample(event, &handle, &sample); | |
7040 | ||
8d1b2d93 | 7041 | perf_output_end(&handle); |
c980d109 ACM |
7042 | out: |
7043 | comm_event->event_id.header.size = size; | |
8d1b2d93 PZ |
7044 | } |
7045 | ||
cdd6c482 | 7046 | static void perf_event_comm_event(struct perf_comm_event *comm_event) |
8d1b2d93 | 7047 | { |
413ee3b4 | 7048 | char comm[TASK_COMM_LEN]; |
8d1b2d93 | 7049 | unsigned int size; |
8d1b2d93 | 7050 | |
413ee3b4 | 7051 | memset(comm, 0, sizeof(comm)); |
96b02d78 | 7052 | strlcpy(comm, comm_event->task->comm, sizeof(comm)); |
888fcee0 | 7053 | size = ALIGN(strlen(comm)+1, sizeof(u64)); |
8d1b2d93 PZ |
7054 | |
7055 | comm_event->comm = comm; | |
7056 | comm_event->comm_size = size; | |
7057 | ||
cdd6c482 | 7058 | comm_event->event_id.header.size = sizeof(comm_event->event_id) + size; |
8dc85d54 | 7059 | |
aab5b71e | 7060 | perf_iterate_sb(perf_event_comm_output, |
52d857a8 JO |
7061 | comm_event, |
7062 | NULL); | |
8d1b2d93 PZ |
7063 | } |
7064 | ||
82b89778 | 7065 | void perf_event_comm(struct task_struct *task, bool exec) |
8d1b2d93 | 7066 | { |
9ee318a7 PZ |
7067 | struct perf_comm_event comm_event; |
7068 | ||
cdd6c482 | 7069 | if (!atomic_read(&nr_comm_events)) |
9ee318a7 | 7070 | return; |
a63eaf34 | 7071 | |
9ee318a7 | 7072 | comm_event = (struct perf_comm_event){ |
8d1b2d93 | 7073 | .task = task, |
573402db PZ |
7074 | /* .comm */ |
7075 | /* .comm_size */ | |
cdd6c482 | 7076 | .event_id = { |
573402db | 7077 | .header = { |
cdd6c482 | 7078 | .type = PERF_RECORD_COMM, |
82b89778 | 7079 | .misc = exec ? PERF_RECORD_MISC_COMM_EXEC : 0, |
573402db PZ |
7080 | /* .size */ |
7081 | }, | |
7082 | /* .pid */ | |
7083 | /* .tid */ | |
8d1b2d93 PZ |
7084 | }, |
7085 | }; | |
7086 | ||
cdd6c482 | 7087 | perf_event_comm_event(&comm_event); |
8d1b2d93 PZ |
7088 | } |
7089 | ||
e4222673 HB |
7090 | /* |
7091 | * namespaces tracking | |
7092 | */ | |
7093 | ||
7094 | struct perf_namespaces_event { | |
7095 | struct task_struct *task; | |
7096 | ||
7097 | struct { | |
7098 | struct perf_event_header header; | |
7099 | ||
7100 | u32 pid; | |
7101 | u32 tid; | |
7102 | u64 nr_namespaces; | |
7103 | struct perf_ns_link_info link_info[NR_NAMESPACES]; | |
7104 | } event_id; | |
7105 | }; | |
7106 | ||
7107 | static int perf_event_namespaces_match(struct perf_event *event) | |
7108 | { | |
7109 | return event->attr.namespaces; | |
7110 | } | |
7111 | ||
7112 | static void perf_event_namespaces_output(struct perf_event *event, | |
7113 | void *data) | |
7114 | { | |
7115 | struct perf_namespaces_event *namespaces_event = data; | |
7116 | struct perf_output_handle handle; | |
7117 | struct perf_sample_data sample; | |
34900ec5 | 7118 | u16 header_size = namespaces_event->event_id.header.size; |
e4222673 HB |
7119 | int ret; |
7120 | ||
7121 | if (!perf_event_namespaces_match(event)) | |
7122 | return; | |
7123 | ||
7124 | perf_event_header__init_id(&namespaces_event->event_id.header, | |
7125 | &sample, event); | |
7126 | ret = perf_output_begin(&handle, event, | |
7127 | namespaces_event->event_id.header.size); | |
7128 | if (ret) | |
34900ec5 | 7129 | goto out; |
e4222673 HB |
7130 | |
7131 | namespaces_event->event_id.pid = perf_event_pid(event, | |
7132 | namespaces_event->task); | |
7133 | namespaces_event->event_id.tid = perf_event_tid(event, | |
7134 | namespaces_event->task); | |
7135 | ||
7136 | perf_output_put(&handle, namespaces_event->event_id); | |
7137 | ||
7138 | perf_event__output_id_sample(event, &handle, &sample); | |
7139 | ||
7140 | perf_output_end(&handle); | |
34900ec5 JO |
7141 | out: |
7142 | namespaces_event->event_id.header.size = header_size; | |
e4222673 HB |
7143 | } |
7144 | ||
7145 | static void perf_fill_ns_link_info(struct perf_ns_link_info *ns_link_info, | |
7146 | struct task_struct *task, | |
7147 | const struct proc_ns_operations *ns_ops) | |
7148 | { | |
7149 | struct path ns_path; | |
7150 | struct inode *ns_inode; | |
7151 | void *error; | |
7152 | ||
7153 | error = ns_get_path(&ns_path, task, ns_ops); | |
7154 | if (!error) { | |
7155 | ns_inode = ns_path.dentry->d_inode; | |
7156 | ns_link_info->dev = new_encode_dev(ns_inode->i_sb->s_dev); | |
7157 | ns_link_info->ino = ns_inode->i_ino; | |
0e18dd12 | 7158 | path_put(&ns_path); |
e4222673 HB |
7159 | } |
7160 | } | |
7161 | ||
7162 | void perf_event_namespaces(struct task_struct *task) | |
7163 | { | |
7164 | struct perf_namespaces_event namespaces_event; | |
7165 | struct perf_ns_link_info *ns_link_info; | |
7166 | ||
7167 | if (!atomic_read(&nr_namespaces_events)) | |
7168 | return; | |
7169 | ||
7170 | namespaces_event = (struct perf_namespaces_event){ | |
7171 | .task = task, | |
7172 | .event_id = { | |
7173 | .header = { | |
7174 | .type = PERF_RECORD_NAMESPACES, | |
7175 | .misc = 0, | |
7176 | .size = sizeof(namespaces_event.event_id), | |
7177 | }, | |
7178 | /* .pid */ | |
7179 | /* .tid */ | |
7180 | .nr_namespaces = NR_NAMESPACES, | |
7181 | /* .link_info[NR_NAMESPACES] */ | |
7182 | }, | |
7183 | }; | |
7184 | ||
7185 | ns_link_info = namespaces_event.event_id.link_info; | |
7186 | ||
7187 | perf_fill_ns_link_info(&ns_link_info[MNT_NS_INDEX], | |
7188 | task, &mntns_operations); | |
7189 | ||
7190 | #ifdef CONFIG_USER_NS | |
7191 | perf_fill_ns_link_info(&ns_link_info[USER_NS_INDEX], | |
7192 | task, &userns_operations); | |
7193 | #endif | |
7194 | #ifdef CONFIG_NET_NS | |
7195 | perf_fill_ns_link_info(&ns_link_info[NET_NS_INDEX], | |
7196 | task, &netns_operations); | |
7197 | #endif | |
7198 | #ifdef CONFIG_UTS_NS | |
7199 | perf_fill_ns_link_info(&ns_link_info[UTS_NS_INDEX], | |
7200 | task, &utsns_operations); | |
7201 | #endif | |
7202 | #ifdef CONFIG_IPC_NS | |
7203 | perf_fill_ns_link_info(&ns_link_info[IPC_NS_INDEX], | |
7204 | task, &ipcns_operations); | |
7205 | #endif | |
7206 | #ifdef CONFIG_PID_NS | |
7207 | perf_fill_ns_link_info(&ns_link_info[PID_NS_INDEX], | |
7208 | task, &pidns_operations); | |
7209 | #endif | |
7210 | #ifdef CONFIG_CGROUPS | |
7211 | perf_fill_ns_link_info(&ns_link_info[CGROUP_NS_INDEX], | |
7212 | task, &cgroupns_operations); | |
7213 | #endif | |
7214 | ||
7215 | perf_iterate_sb(perf_event_namespaces_output, | |
7216 | &namespaces_event, | |
7217 | NULL); | |
7218 | } | |
7219 | ||
0a4a9391 PZ |
7220 | /* |
7221 | * mmap tracking | |
7222 | */ | |
7223 | ||
7224 | struct perf_mmap_event { | |
089dd79d PZ |
7225 | struct vm_area_struct *vma; |
7226 | ||
7227 | const char *file_name; | |
7228 | int file_size; | |
13d7a241 SE |
7229 | int maj, min; |
7230 | u64 ino; | |
7231 | u64 ino_generation; | |
f972eb63 | 7232 | u32 prot, flags; |
0a4a9391 PZ |
7233 | |
7234 | struct { | |
7235 | struct perf_event_header header; | |
7236 | ||
7237 | u32 pid; | |
7238 | u32 tid; | |
7239 | u64 start; | |
7240 | u64 len; | |
7241 | u64 pgoff; | |
cdd6c482 | 7242 | } event_id; |
0a4a9391 PZ |
7243 | }; |
7244 | ||
67516844 JO |
7245 | static int perf_event_mmap_match(struct perf_event *event, |
7246 | void *data) | |
7247 | { | |
7248 | struct perf_mmap_event *mmap_event = data; | |
7249 | struct vm_area_struct *vma = mmap_event->vma; | |
7250 | int executable = vma->vm_flags & VM_EXEC; | |
7251 | ||
7252 | return (!executable && event->attr.mmap_data) || | |
13d7a241 | 7253 | (executable && (event->attr.mmap || event->attr.mmap2)); |
67516844 JO |
7254 | } |
7255 | ||
cdd6c482 | 7256 | static void perf_event_mmap_output(struct perf_event *event, |
52d857a8 | 7257 | void *data) |
0a4a9391 | 7258 | { |
52d857a8 | 7259 | struct perf_mmap_event *mmap_event = data; |
0a4a9391 | 7260 | struct perf_output_handle handle; |
c980d109 | 7261 | struct perf_sample_data sample; |
cdd6c482 | 7262 | int size = mmap_event->event_id.header.size; |
d9c1bb2f | 7263 | u32 type = mmap_event->event_id.header.type; |
c980d109 | 7264 | int ret; |
0a4a9391 | 7265 | |
67516844 JO |
7266 | if (!perf_event_mmap_match(event, data)) |
7267 | return; | |
7268 | ||
13d7a241 SE |
7269 | if (event->attr.mmap2) { |
7270 | mmap_event->event_id.header.type = PERF_RECORD_MMAP2; | |
7271 | mmap_event->event_id.header.size += sizeof(mmap_event->maj); | |
7272 | mmap_event->event_id.header.size += sizeof(mmap_event->min); | |
7273 | mmap_event->event_id.header.size += sizeof(mmap_event->ino); | |
d008d525 | 7274 | mmap_event->event_id.header.size += sizeof(mmap_event->ino_generation); |
f972eb63 PZ |
7275 | mmap_event->event_id.header.size += sizeof(mmap_event->prot); |
7276 | mmap_event->event_id.header.size += sizeof(mmap_event->flags); | |
13d7a241 SE |
7277 | } |
7278 | ||
c980d109 ACM |
7279 | perf_event_header__init_id(&mmap_event->event_id.header, &sample, event); |
7280 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 7281 | mmap_event->event_id.header.size); |
0a4a9391 | 7282 | if (ret) |
c980d109 | 7283 | goto out; |
0a4a9391 | 7284 | |
cdd6c482 IM |
7285 | mmap_event->event_id.pid = perf_event_pid(event, current); |
7286 | mmap_event->event_id.tid = perf_event_tid(event, current); | |
709e50cf | 7287 | |
cdd6c482 | 7288 | perf_output_put(&handle, mmap_event->event_id); |
13d7a241 SE |
7289 | |
7290 | if (event->attr.mmap2) { | |
7291 | perf_output_put(&handle, mmap_event->maj); | |
7292 | perf_output_put(&handle, mmap_event->min); | |
7293 | perf_output_put(&handle, mmap_event->ino); | |
7294 | perf_output_put(&handle, mmap_event->ino_generation); | |
f972eb63 PZ |
7295 | perf_output_put(&handle, mmap_event->prot); |
7296 | perf_output_put(&handle, mmap_event->flags); | |
13d7a241 SE |
7297 | } |
7298 | ||
76369139 | 7299 | __output_copy(&handle, mmap_event->file_name, |
0a4a9391 | 7300 | mmap_event->file_size); |
c980d109 ACM |
7301 | |
7302 | perf_event__output_id_sample(event, &handle, &sample); | |
7303 | ||
78d613eb | 7304 | perf_output_end(&handle); |
c980d109 ACM |
7305 | out: |
7306 | mmap_event->event_id.header.size = size; | |
d9c1bb2f | 7307 | mmap_event->event_id.header.type = type; |
0a4a9391 PZ |
7308 | } |
7309 | ||
cdd6c482 | 7310 | static void perf_event_mmap_event(struct perf_mmap_event *mmap_event) |
0a4a9391 | 7311 | { |
089dd79d PZ |
7312 | struct vm_area_struct *vma = mmap_event->vma; |
7313 | struct file *file = vma->vm_file; | |
13d7a241 SE |
7314 | int maj = 0, min = 0; |
7315 | u64 ino = 0, gen = 0; | |
f972eb63 | 7316 | u32 prot = 0, flags = 0; |
0a4a9391 PZ |
7317 | unsigned int size; |
7318 | char tmp[16]; | |
7319 | char *buf = NULL; | |
2c42cfbf | 7320 | char *name; |
413ee3b4 | 7321 | |
0b3589be PZ |
7322 | if (vma->vm_flags & VM_READ) |
7323 | prot |= PROT_READ; | |
7324 | if (vma->vm_flags & VM_WRITE) | |
7325 | prot |= PROT_WRITE; | |
7326 | if (vma->vm_flags & VM_EXEC) | |
7327 | prot |= PROT_EXEC; | |
7328 | ||
7329 | if (vma->vm_flags & VM_MAYSHARE) | |
7330 | flags = MAP_SHARED; | |
7331 | else | |
7332 | flags = MAP_PRIVATE; | |
7333 | ||
7334 | if (vma->vm_flags & VM_DENYWRITE) | |
7335 | flags |= MAP_DENYWRITE; | |
7336 | if (vma->vm_flags & VM_MAYEXEC) | |
7337 | flags |= MAP_EXECUTABLE; | |
7338 | if (vma->vm_flags & VM_LOCKED) | |
7339 | flags |= MAP_LOCKED; | |
7340 | if (vma->vm_flags & VM_HUGETLB) | |
7341 | flags |= MAP_HUGETLB; | |
7342 | ||
0a4a9391 | 7343 | if (file) { |
13d7a241 SE |
7344 | struct inode *inode; |
7345 | dev_t dev; | |
3ea2f2b9 | 7346 | |
2c42cfbf | 7347 | buf = kmalloc(PATH_MAX, GFP_KERNEL); |
0a4a9391 | 7348 | if (!buf) { |
c7e548b4 ON |
7349 | name = "//enomem"; |
7350 | goto cpy_name; | |
0a4a9391 | 7351 | } |
413ee3b4 | 7352 | /* |
3ea2f2b9 | 7353 | * d_path() works from the end of the rb backwards, so we |
413ee3b4 AB |
7354 | * need to add enough zero bytes after the string to handle |
7355 | * the 64bit alignment we do later. | |
7356 | */ | |
9bf39ab2 | 7357 | name = file_path(file, buf, PATH_MAX - sizeof(u64)); |
0a4a9391 | 7358 | if (IS_ERR(name)) { |
c7e548b4 ON |
7359 | name = "//toolong"; |
7360 | goto cpy_name; | |
0a4a9391 | 7361 | } |
13d7a241 SE |
7362 | inode = file_inode(vma->vm_file); |
7363 | dev = inode->i_sb->s_dev; | |
7364 | ino = inode->i_ino; | |
7365 | gen = inode->i_generation; | |
7366 | maj = MAJOR(dev); | |
7367 | min = MINOR(dev); | |
f972eb63 | 7368 | |
c7e548b4 | 7369 | goto got_name; |
0a4a9391 | 7370 | } else { |
fbe26abe JO |
7371 | if (vma->vm_ops && vma->vm_ops->name) { |
7372 | name = (char *) vma->vm_ops->name(vma); | |
7373 | if (name) | |
7374 | goto cpy_name; | |
7375 | } | |
7376 | ||
2c42cfbf | 7377 | name = (char *)arch_vma_name(vma); |
c7e548b4 ON |
7378 | if (name) |
7379 | goto cpy_name; | |
089dd79d | 7380 | |
32c5fb7e | 7381 | if (vma->vm_start <= vma->vm_mm->start_brk && |
3af9e859 | 7382 | vma->vm_end >= vma->vm_mm->brk) { |
c7e548b4 ON |
7383 | name = "[heap]"; |
7384 | goto cpy_name; | |
32c5fb7e ON |
7385 | } |
7386 | if (vma->vm_start <= vma->vm_mm->start_stack && | |
3af9e859 | 7387 | vma->vm_end >= vma->vm_mm->start_stack) { |
c7e548b4 ON |
7388 | name = "[stack]"; |
7389 | goto cpy_name; | |
089dd79d PZ |
7390 | } |
7391 | ||
c7e548b4 ON |
7392 | name = "//anon"; |
7393 | goto cpy_name; | |
0a4a9391 PZ |
7394 | } |
7395 | ||
c7e548b4 ON |
7396 | cpy_name: |
7397 | strlcpy(tmp, name, sizeof(tmp)); | |
7398 | name = tmp; | |
0a4a9391 | 7399 | got_name: |
2c42cfbf PZ |
7400 | /* |
7401 | * Since our buffer works in 8 byte units we need to align our string | |
7402 | * size to a multiple of 8. However, we must guarantee the tail end is | |
7403 | * zero'd out to avoid leaking random bits to userspace. | |
7404 | */ | |
7405 | size = strlen(name)+1; | |
7406 | while (!IS_ALIGNED(size, sizeof(u64))) | |
7407 | name[size++] = '\0'; | |
0a4a9391 PZ |
7408 | |
7409 | mmap_event->file_name = name; | |
7410 | mmap_event->file_size = size; | |
13d7a241 SE |
7411 | mmap_event->maj = maj; |
7412 | mmap_event->min = min; | |
7413 | mmap_event->ino = ino; | |
7414 | mmap_event->ino_generation = gen; | |
f972eb63 PZ |
7415 | mmap_event->prot = prot; |
7416 | mmap_event->flags = flags; | |
0a4a9391 | 7417 | |
2fe85427 SE |
7418 | if (!(vma->vm_flags & VM_EXEC)) |
7419 | mmap_event->event_id.header.misc |= PERF_RECORD_MISC_MMAP_DATA; | |
7420 | ||
cdd6c482 | 7421 | mmap_event->event_id.header.size = sizeof(mmap_event->event_id) + size; |
0a4a9391 | 7422 | |
aab5b71e | 7423 | perf_iterate_sb(perf_event_mmap_output, |
52d857a8 JO |
7424 | mmap_event, |
7425 | NULL); | |
665c2142 | 7426 | |
0a4a9391 PZ |
7427 | kfree(buf); |
7428 | } | |
7429 | ||
375637bc AS |
7430 | /* |
7431 | * Check whether inode and address range match filter criteria. | |
7432 | */ | |
7433 | static bool perf_addr_filter_match(struct perf_addr_filter *filter, | |
7434 | struct file *file, unsigned long offset, | |
7435 | unsigned long size) | |
7436 | { | |
7f635ff1 MP |
7437 | /* d_inode(NULL) won't be equal to any mapped user-space file */ |
7438 | if (!filter->path.dentry) | |
7439 | return false; | |
7440 | ||
9511bce9 | 7441 | if (d_inode(filter->path.dentry) != file_inode(file)) |
375637bc AS |
7442 | return false; |
7443 | ||
7444 | if (filter->offset > offset + size) | |
7445 | return false; | |
7446 | ||
7447 | if (filter->offset + filter->size < offset) | |
7448 | return false; | |
7449 | ||
7450 | return true; | |
7451 | } | |
7452 | ||
c60f83b8 AS |
7453 | static bool perf_addr_filter_vma_adjust(struct perf_addr_filter *filter, |
7454 | struct vm_area_struct *vma, | |
7455 | struct perf_addr_filter_range *fr) | |
7456 | { | |
7457 | unsigned long vma_size = vma->vm_end - vma->vm_start; | |
7458 | unsigned long off = vma->vm_pgoff << PAGE_SHIFT; | |
7459 | struct file *file = vma->vm_file; | |
7460 | ||
7461 | if (!perf_addr_filter_match(filter, file, off, vma_size)) | |
7462 | return false; | |
7463 | ||
7464 | if (filter->offset < off) { | |
7465 | fr->start = vma->vm_start; | |
7466 | fr->size = min(vma_size, filter->size - (off - filter->offset)); | |
7467 | } else { | |
7468 | fr->start = vma->vm_start + filter->offset - off; | |
7469 | fr->size = min(vma->vm_end - fr->start, filter->size); | |
7470 | } | |
7471 | ||
7472 | return true; | |
7473 | } | |
7474 | ||
375637bc AS |
7475 | static void __perf_addr_filters_adjust(struct perf_event *event, void *data) |
7476 | { | |
7477 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
7478 | struct vm_area_struct *vma = data; | |
375637bc AS |
7479 | struct perf_addr_filter *filter; |
7480 | unsigned int restart = 0, count = 0; | |
c60f83b8 | 7481 | unsigned long flags; |
375637bc AS |
7482 | |
7483 | if (!has_addr_filter(event)) | |
7484 | return; | |
7485 | ||
c60f83b8 | 7486 | if (!vma->vm_file) |
375637bc AS |
7487 | return; |
7488 | ||
7489 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
7490 | list_for_each_entry(filter, &ifh->list, entry) { | |
c60f83b8 AS |
7491 | if (perf_addr_filter_vma_adjust(filter, vma, |
7492 | &event->addr_filter_ranges[count])) | |
375637bc | 7493 | restart++; |
375637bc AS |
7494 | |
7495 | count++; | |
7496 | } | |
7497 | ||
7498 | if (restart) | |
7499 | event->addr_filters_gen++; | |
7500 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
7501 | ||
7502 | if (restart) | |
767ae086 | 7503 | perf_event_stop(event, 1); |
375637bc AS |
7504 | } |
7505 | ||
7506 | /* | |
7507 | * Adjust all task's events' filters to the new vma | |
7508 | */ | |
7509 | static void perf_addr_filters_adjust(struct vm_area_struct *vma) | |
7510 | { | |
7511 | struct perf_event_context *ctx; | |
7512 | int ctxn; | |
7513 | ||
12b40a23 MP |
7514 | /* |
7515 | * Data tracing isn't supported yet and as such there is no need | |
7516 | * to keep track of anything that isn't related to executable code: | |
7517 | */ | |
7518 | if (!(vma->vm_flags & VM_EXEC)) | |
7519 | return; | |
7520 | ||
375637bc AS |
7521 | rcu_read_lock(); |
7522 | for_each_task_context_nr(ctxn) { | |
7523 | ctx = rcu_dereference(current->perf_event_ctxp[ctxn]); | |
7524 | if (!ctx) | |
7525 | continue; | |
7526 | ||
aab5b71e | 7527 | perf_iterate_ctx(ctx, __perf_addr_filters_adjust, vma, true); |
375637bc AS |
7528 | } |
7529 | rcu_read_unlock(); | |
7530 | } | |
7531 | ||
3af9e859 | 7532 | void perf_event_mmap(struct vm_area_struct *vma) |
0a4a9391 | 7533 | { |
9ee318a7 PZ |
7534 | struct perf_mmap_event mmap_event; |
7535 | ||
cdd6c482 | 7536 | if (!atomic_read(&nr_mmap_events)) |
9ee318a7 PZ |
7537 | return; |
7538 | ||
7539 | mmap_event = (struct perf_mmap_event){ | |
089dd79d | 7540 | .vma = vma, |
573402db PZ |
7541 | /* .file_name */ |
7542 | /* .file_size */ | |
cdd6c482 | 7543 | .event_id = { |
573402db | 7544 | .header = { |
cdd6c482 | 7545 | .type = PERF_RECORD_MMAP, |
39447b38 | 7546 | .misc = PERF_RECORD_MISC_USER, |
573402db PZ |
7547 | /* .size */ |
7548 | }, | |
7549 | /* .pid */ | |
7550 | /* .tid */ | |
089dd79d PZ |
7551 | .start = vma->vm_start, |
7552 | .len = vma->vm_end - vma->vm_start, | |
3a0304e9 | 7553 | .pgoff = (u64)vma->vm_pgoff << PAGE_SHIFT, |
0a4a9391 | 7554 | }, |
13d7a241 SE |
7555 | /* .maj (attr_mmap2 only) */ |
7556 | /* .min (attr_mmap2 only) */ | |
7557 | /* .ino (attr_mmap2 only) */ | |
7558 | /* .ino_generation (attr_mmap2 only) */ | |
f972eb63 PZ |
7559 | /* .prot (attr_mmap2 only) */ |
7560 | /* .flags (attr_mmap2 only) */ | |
0a4a9391 PZ |
7561 | }; |
7562 | ||
375637bc | 7563 | perf_addr_filters_adjust(vma); |
cdd6c482 | 7564 | perf_event_mmap_event(&mmap_event); |
0a4a9391 PZ |
7565 | } |
7566 | ||
68db7e98 AS |
7567 | void perf_event_aux_event(struct perf_event *event, unsigned long head, |
7568 | unsigned long size, u64 flags) | |
7569 | { | |
7570 | struct perf_output_handle handle; | |
7571 | struct perf_sample_data sample; | |
7572 | struct perf_aux_event { | |
7573 | struct perf_event_header header; | |
7574 | u64 offset; | |
7575 | u64 size; | |
7576 | u64 flags; | |
7577 | } rec = { | |
7578 | .header = { | |
7579 | .type = PERF_RECORD_AUX, | |
7580 | .misc = 0, | |
7581 | .size = sizeof(rec), | |
7582 | }, | |
7583 | .offset = head, | |
7584 | .size = size, | |
7585 | .flags = flags, | |
7586 | }; | |
7587 | int ret; | |
7588 | ||
7589 | perf_event_header__init_id(&rec.header, &sample, event); | |
7590 | ret = perf_output_begin(&handle, event, rec.header.size); | |
7591 | ||
7592 | if (ret) | |
7593 | return; | |
7594 | ||
7595 | perf_output_put(&handle, rec); | |
7596 | perf_event__output_id_sample(event, &handle, &sample); | |
7597 | ||
7598 | perf_output_end(&handle); | |
7599 | } | |
7600 | ||
f38b0dbb KL |
7601 | /* |
7602 | * Lost/dropped samples logging | |
7603 | */ | |
7604 | void perf_log_lost_samples(struct perf_event *event, u64 lost) | |
7605 | { | |
7606 | struct perf_output_handle handle; | |
7607 | struct perf_sample_data sample; | |
7608 | int ret; | |
7609 | ||
7610 | struct { | |
7611 | struct perf_event_header header; | |
7612 | u64 lost; | |
7613 | } lost_samples_event = { | |
7614 | .header = { | |
7615 | .type = PERF_RECORD_LOST_SAMPLES, | |
7616 | .misc = 0, | |
7617 | .size = sizeof(lost_samples_event), | |
7618 | }, | |
7619 | .lost = lost, | |
7620 | }; | |
7621 | ||
7622 | perf_event_header__init_id(&lost_samples_event.header, &sample, event); | |
7623 | ||
7624 | ret = perf_output_begin(&handle, event, | |
7625 | lost_samples_event.header.size); | |
7626 | if (ret) | |
7627 | return; | |
7628 | ||
7629 | perf_output_put(&handle, lost_samples_event); | |
7630 | perf_event__output_id_sample(event, &handle, &sample); | |
7631 | perf_output_end(&handle); | |
7632 | } | |
7633 | ||
45ac1403 AH |
7634 | /* |
7635 | * context_switch tracking | |
7636 | */ | |
7637 | ||
7638 | struct perf_switch_event { | |
7639 | struct task_struct *task; | |
7640 | struct task_struct *next_prev; | |
7641 | ||
7642 | struct { | |
7643 | struct perf_event_header header; | |
7644 | u32 next_prev_pid; | |
7645 | u32 next_prev_tid; | |
7646 | } event_id; | |
7647 | }; | |
7648 | ||
7649 | static int perf_event_switch_match(struct perf_event *event) | |
7650 | { | |
7651 | return event->attr.context_switch; | |
7652 | } | |
7653 | ||
7654 | static void perf_event_switch_output(struct perf_event *event, void *data) | |
7655 | { | |
7656 | struct perf_switch_event *se = data; | |
7657 | struct perf_output_handle handle; | |
7658 | struct perf_sample_data sample; | |
7659 | int ret; | |
7660 | ||
7661 | if (!perf_event_switch_match(event)) | |
7662 | return; | |
7663 | ||
7664 | /* Only CPU-wide events are allowed to see next/prev pid/tid */ | |
7665 | if (event->ctx->task) { | |
7666 | se->event_id.header.type = PERF_RECORD_SWITCH; | |
7667 | se->event_id.header.size = sizeof(se->event_id.header); | |
7668 | } else { | |
7669 | se->event_id.header.type = PERF_RECORD_SWITCH_CPU_WIDE; | |
7670 | se->event_id.header.size = sizeof(se->event_id); | |
7671 | se->event_id.next_prev_pid = | |
7672 | perf_event_pid(event, se->next_prev); | |
7673 | se->event_id.next_prev_tid = | |
7674 | perf_event_tid(event, se->next_prev); | |
7675 | } | |
7676 | ||
7677 | perf_event_header__init_id(&se->event_id.header, &sample, event); | |
7678 | ||
7679 | ret = perf_output_begin(&handle, event, se->event_id.header.size); | |
7680 | if (ret) | |
7681 | return; | |
7682 | ||
7683 | if (event->ctx->task) | |
7684 | perf_output_put(&handle, se->event_id.header); | |
7685 | else | |
7686 | perf_output_put(&handle, se->event_id); | |
7687 | ||
7688 | perf_event__output_id_sample(event, &handle, &sample); | |
7689 | ||
7690 | perf_output_end(&handle); | |
7691 | } | |
7692 | ||
7693 | static void perf_event_switch(struct task_struct *task, | |
7694 | struct task_struct *next_prev, bool sched_in) | |
7695 | { | |
7696 | struct perf_switch_event switch_event; | |
7697 | ||
7698 | /* N.B. caller checks nr_switch_events != 0 */ | |
7699 | ||
7700 | switch_event = (struct perf_switch_event){ | |
7701 | .task = task, | |
7702 | .next_prev = next_prev, | |
7703 | .event_id = { | |
7704 | .header = { | |
7705 | /* .type */ | |
7706 | .misc = sched_in ? 0 : PERF_RECORD_MISC_SWITCH_OUT, | |
7707 | /* .size */ | |
7708 | }, | |
7709 | /* .next_prev_pid */ | |
7710 | /* .next_prev_tid */ | |
7711 | }, | |
7712 | }; | |
7713 | ||
101592b4 AB |
7714 | if (!sched_in && task->state == TASK_RUNNING) |
7715 | switch_event.event_id.header.misc |= | |
7716 | PERF_RECORD_MISC_SWITCH_OUT_PREEMPT; | |
7717 | ||
aab5b71e | 7718 | perf_iterate_sb(perf_event_switch_output, |
45ac1403 AH |
7719 | &switch_event, |
7720 | NULL); | |
7721 | } | |
7722 | ||
a78ac325 PZ |
7723 | /* |
7724 | * IRQ throttle logging | |
7725 | */ | |
7726 | ||
cdd6c482 | 7727 | static void perf_log_throttle(struct perf_event *event, int enable) |
a78ac325 PZ |
7728 | { |
7729 | struct perf_output_handle handle; | |
c980d109 | 7730 | struct perf_sample_data sample; |
a78ac325 PZ |
7731 | int ret; |
7732 | ||
7733 | struct { | |
7734 | struct perf_event_header header; | |
7735 | u64 time; | |
cca3f454 | 7736 | u64 id; |
7f453c24 | 7737 | u64 stream_id; |
a78ac325 PZ |
7738 | } throttle_event = { |
7739 | .header = { | |
cdd6c482 | 7740 | .type = PERF_RECORD_THROTTLE, |
a78ac325 PZ |
7741 | .misc = 0, |
7742 | .size = sizeof(throttle_event), | |
7743 | }, | |
34f43927 | 7744 | .time = perf_event_clock(event), |
cdd6c482 IM |
7745 | .id = primary_event_id(event), |
7746 | .stream_id = event->id, | |
a78ac325 PZ |
7747 | }; |
7748 | ||
966ee4d6 | 7749 | if (enable) |
cdd6c482 | 7750 | throttle_event.header.type = PERF_RECORD_UNTHROTTLE; |
966ee4d6 | 7751 | |
c980d109 ACM |
7752 | perf_event_header__init_id(&throttle_event.header, &sample, event); |
7753 | ||
7754 | ret = perf_output_begin(&handle, event, | |
a7ac67ea | 7755 | throttle_event.header.size); |
a78ac325 PZ |
7756 | if (ret) |
7757 | return; | |
7758 | ||
7759 | perf_output_put(&handle, throttle_event); | |
c980d109 | 7760 | perf_event__output_id_sample(event, &handle, &sample); |
a78ac325 PZ |
7761 | perf_output_end(&handle); |
7762 | } | |
7763 | ||
76193a94 SL |
7764 | /* |
7765 | * ksymbol register/unregister tracking | |
7766 | */ | |
7767 | ||
7768 | struct perf_ksymbol_event { | |
7769 | const char *name; | |
7770 | int name_len; | |
7771 | struct { | |
7772 | struct perf_event_header header; | |
7773 | u64 addr; | |
7774 | u32 len; | |
7775 | u16 ksym_type; | |
7776 | u16 flags; | |
7777 | } event_id; | |
7778 | }; | |
7779 | ||
7780 | static int perf_event_ksymbol_match(struct perf_event *event) | |
7781 | { | |
7782 | return event->attr.ksymbol; | |
7783 | } | |
7784 | ||
7785 | static void perf_event_ksymbol_output(struct perf_event *event, void *data) | |
7786 | { | |
7787 | struct perf_ksymbol_event *ksymbol_event = data; | |
7788 | struct perf_output_handle handle; | |
7789 | struct perf_sample_data sample; | |
7790 | int ret; | |
7791 | ||
7792 | if (!perf_event_ksymbol_match(event)) | |
7793 | return; | |
7794 | ||
7795 | perf_event_header__init_id(&ksymbol_event->event_id.header, | |
7796 | &sample, event); | |
7797 | ret = perf_output_begin(&handle, event, | |
7798 | ksymbol_event->event_id.header.size); | |
7799 | if (ret) | |
7800 | return; | |
7801 | ||
7802 | perf_output_put(&handle, ksymbol_event->event_id); | |
7803 | __output_copy(&handle, ksymbol_event->name, ksymbol_event->name_len); | |
7804 | perf_event__output_id_sample(event, &handle, &sample); | |
7805 | ||
7806 | perf_output_end(&handle); | |
7807 | } | |
7808 | ||
7809 | void perf_event_ksymbol(u16 ksym_type, u64 addr, u32 len, bool unregister, | |
7810 | const char *sym) | |
7811 | { | |
7812 | struct perf_ksymbol_event ksymbol_event; | |
7813 | char name[KSYM_NAME_LEN]; | |
7814 | u16 flags = 0; | |
7815 | int name_len; | |
7816 | ||
7817 | if (!atomic_read(&nr_ksymbol_events)) | |
7818 | return; | |
7819 | ||
7820 | if (ksym_type >= PERF_RECORD_KSYMBOL_TYPE_MAX || | |
7821 | ksym_type == PERF_RECORD_KSYMBOL_TYPE_UNKNOWN) | |
7822 | goto err; | |
7823 | ||
7824 | strlcpy(name, sym, KSYM_NAME_LEN); | |
7825 | name_len = strlen(name) + 1; | |
7826 | while (!IS_ALIGNED(name_len, sizeof(u64))) | |
7827 | name[name_len++] = '\0'; | |
7828 | BUILD_BUG_ON(KSYM_NAME_LEN % sizeof(u64)); | |
7829 | ||
7830 | if (unregister) | |
7831 | flags |= PERF_RECORD_KSYMBOL_FLAGS_UNREGISTER; | |
7832 | ||
7833 | ksymbol_event = (struct perf_ksymbol_event){ | |
7834 | .name = name, | |
7835 | .name_len = name_len, | |
7836 | .event_id = { | |
7837 | .header = { | |
7838 | .type = PERF_RECORD_KSYMBOL, | |
7839 | .size = sizeof(ksymbol_event.event_id) + | |
7840 | name_len, | |
7841 | }, | |
7842 | .addr = addr, | |
7843 | .len = len, | |
7844 | .ksym_type = ksym_type, | |
7845 | .flags = flags, | |
7846 | }, | |
7847 | }; | |
7848 | ||
7849 | perf_iterate_sb(perf_event_ksymbol_output, &ksymbol_event, NULL); | |
7850 | return; | |
7851 | err: | |
7852 | WARN_ONCE(1, "%s: Invalid KSYMBOL type 0x%x\n", __func__, ksym_type); | |
7853 | } | |
7854 | ||
6ee52e2a SL |
7855 | /* |
7856 | * bpf program load/unload tracking | |
7857 | */ | |
7858 | ||
7859 | struct perf_bpf_event { | |
7860 | struct bpf_prog *prog; | |
7861 | struct { | |
7862 | struct perf_event_header header; | |
7863 | u16 type; | |
7864 | u16 flags; | |
7865 | u32 id; | |
7866 | u8 tag[BPF_TAG_SIZE]; | |
7867 | } event_id; | |
7868 | }; | |
7869 | ||
7870 | static int perf_event_bpf_match(struct perf_event *event) | |
7871 | { | |
7872 | return event->attr.bpf_event; | |
7873 | } | |
7874 | ||
7875 | static void perf_event_bpf_output(struct perf_event *event, void *data) | |
7876 | { | |
7877 | struct perf_bpf_event *bpf_event = data; | |
7878 | struct perf_output_handle handle; | |
7879 | struct perf_sample_data sample; | |
7880 | int ret; | |
7881 | ||
7882 | if (!perf_event_bpf_match(event)) | |
7883 | return; | |
7884 | ||
7885 | perf_event_header__init_id(&bpf_event->event_id.header, | |
7886 | &sample, event); | |
7887 | ret = perf_output_begin(&handle, event, | |
7888 | bpf_event->event_id.header.size); | |
7889 | if (ret) | |
7890 | return; | |
7891 | ||
7892 | perf_output_put(&handle, bpf_event->event_id); | |
7893 | perf_event__output_id_sample(event, &handle, &sample); | |
7894 | ||
7895 | perf_output_end(&handle); | |
7896 | } | |
7897 | ||
7898 | static void perf_event_bpf_emit_ksymbols(struct bpf_prog *prog, | |
7899 | enum perf_bpf_event_type type) | |
7900 | { | |
7901 | bool unregister = type == PERF_BPF_EVENT_PROG_UNLOAD; | |
7902 | char sym[KSYM_NAME_LEN]; | |
7903 | int i; | |
7904 | ||
7905 | if (prog->aux->func_cnt == 0) { | |
7906 | bpf_get_prog_name(prog, sym); | |
7907 | perf_event_ksymbol(PERF_RECORD_KSYMBOL_TYPE_BPF, | |
7908 | (u64)(unsigned long)prog->bpf_func, | |
7909 | prog->jited_len, unregister, sym); | |
7910 | } else { | |
7911 | for (i = 0; i < prog->aux->func_cnt; i++) { | |
7912 | struct bpf_prog *subprog = prog->aux->func[i]; | |
7913 | ||
7914 | bpf_get_prog_name(subprog, sym); | |
7915 | perf_event_ksymbol( | |
7916 | PERF_RECORD_KSYMBOL_TYPE_BPF, | |
7917 | (u64)(unsigned long)subprog->bpf_func, | |
7918 | subprog->jited_len, unregister, sym); | |
7919 | } | |
7920 | } | |
7921 | } | |
7922 | ||
7923 | void perf_event_bpf_event(struct bpf_prog *prog, | |
7924 | enum perf_bpf_event_type type, | |
7925 | u16 flags) | |
7926 | { | |
7927 | struct perf_bpf_event bpf_event; | |
7928 | ||
7929 | if (type <= PERF_BPF_EVENT_UNKNOWN || | |
7930 | type >= PERF_BPF_EVENT_MAX) | |
7931 | return; | |
7932 | ||
7933 | switch (type) { | |
7934 | case PERF_BPF_EVENT_PROG_LOAD: | |
7935 | case PERF_BPF_EVENT_PROG_UNLOAD: | |
7936 | if (atomic_read(&nr_ksymbol_events)) | |
7937 | perf_event_bpf_emit_ksymbols(prog, type); | |
7938 | break; | |
7939 | default: | |
7940 | break; | |
7941 | } | |
7942 | ||
7943 | if (!atomic_read(&nr_bpf_events)) | |
7944 | return; | |
7945 | ||
7946 | bpf_event = (struct perf_bpf_event){ | |
7947 | .prog = prog, | |
7948 | .event_id = { | |
7949 | .header = { | |
7950 | .type = PERF_RECORD_BPF_EVENT, | |
7951 | .size = sizeof(bpf_event.event_id), | |
7952 | }, | |
7953 | .type = type, | |
7954 | .flags = flags, | |
7955 | .id = prog->aux->id, | |
7956 | }, | |
7957 | }; | |
7958 | ||
7959 | BUILD_BUG_ON(BPF_TAG_SIZE % sizeof(u64)); | |
7960 | ||
7961 | memcpy(bpf_event.event_id.tag, prog->tag, BPF_TAG_SIZE); | |
7962 | perf_iterate_sb(perf_event_bpf_output, &bpf_event, NULL); | |
7963 | } | |
7964 | ||
8d4e6c4c AS |
7965 | void perf_event_itrace_started(struct perf_event *event) |
7966 | { | |
7967 | event->attach_state |= PERF_ATTACH_ITRACE; | |
7968 | } | |
7969 | ||
ec0d7729 AS |
7970 | static void perf_log_itrace_start(struct perf_event *event) |
7971 | { | |
7972 | struct perf_output_handle handle; | |
7973 | struct perf_sample_data sample; | |
7974 | struct perf_aux_event { | |
7975 | struct perf_event_header header; | |
7976 | u32 pid; | |
7977 | u32 tid; | |
7978 | } rec; | |
7979 | int ret; | |
7980 | ||
7981 | if (event->parent) | |
7982 | event = event->parent; | |
7983 | ||
7984 | if (!(event->pmu->capabilities & PERF_PMU_CAP_ITRACE) || | |
8d4e6c4c | 7985 | event->attach_state & PERF_ATTACH_ITRACE) |
ec0d7729 AS |
7986 | return; |
7987 | ||
ec0d7729 AS |
7988 | rec.header.type = PERF_RECORD_ITRACE_START; |
7989 | rec.header.misc = 0; | |
7990 | rec.header.size = sizeof(rec); | |
7991 | rec.pid = perf_event_pid(event, current); | |
7992 | rec.tid = perf_event_tid(event, current); | |
7993 | ||
7994 | perf_event_header__init_id(&rec.header, &sample, event); | |
7995 | ret = perf_output_begin(&handle, event, rec.header.size); | |
7996 | ||
7997 | if (ret) | |
7998 | return; | |
7999 | ||
8000 | perf_output_put(&handle, rec); | |
8001 | perf_event__output_id_sample(event, &handle, &sample); | |
8002 | ||
8003 | perf_output_end(&handle); | |
8004 | } | |
8005 | ||
475113d9 JO |
8006 | static int |
8007 | __perf_event_account_interrupt(struct perf_event *event, int throttle) | |
f6c7d5fe | 8008 | { |
cdd6c482 | 8009 | struct hw_perf_event *hwc = &event->hw; |
79f14641 | 8010 | int ret = 0; |
475113d9 | 8011 | u64 seq; |
96398826 | 8012 | |
e050e3f0 SE |
8013 | seq = __this_cpu_read(perf_throttled_seq); |
8014 | if (seq != hwc->interrupts_seq) { | |
8015 | hwc->interrupts_seq = seq; | |
8016 | hwc->interrupts = 1; | |
8017 | } else { | |
8018 | hwc->interrupts++; | |
8019 | if (unlikely(throttle | |
8020 | && hwc->interrupts >= max_samples_per_tick)) { | |
8021 | __this_cpu_inc(perf_throttled_count); | |
555e0c1e | 8022 | tick_dep_set_cpu(smp_processor_id(), TICK_DEP_BIT_PERF_EVENTS); |
163ec435 PZ |
8023 | hwc->interrupts = MAX_INTERRUPTS; |
8024 | perf_log_throttle(event, 0); | |
a78ac325 PZ |
8025 | ret = 1; |
8026 | } | |
e050e3f0 | 8027 | } |
60db5e09 | 8028 | |
cdd6c482 | 8029 | if (event->attr.freq) { |
def0a9b2 | 8030 | u64 now = perf_clock(); |
abd50713 | 8031 | s64 delta = now - hwc->freq_time_stamp; |
bd2b5b12 | 8032 | |
abd50713 | 8033 | hwc->freq_time_stamp = now; |
bd2b5b12 | 8034 | |
abd50713 | 8035 | if (delta > 0 && delta < 2*TICK_NSEC) |
f39d47ff | 8036 | perf_adjust_period(event, delta, hwc->last_period, true); |
bd2b5b12 PZ |
8037 | } |
8038 | ||
475113d9 JO |
8039 | return ret; |
8040 | } | |
8041 | ||
8042 | int perf_event_account_interrupt(struct perf_event *event) | |
8043 | { | |
8044 | return __perf_event_account_interrupt(event, 1); | |
8045 | } | |
8046 | ||
8047 | /* | |
8048 | * Generic event overflow handling, sampling. | |
8049 | */ | |
8050 | ||
8051 | static int __perf_event_overflow(struct perf_event *event, | |
8052 | int throttle, struct perf_sample_data *data, | |
8053 | struct pt_regs *regs) | |
8054 | { | |
8055 | int events = atomic_read(&event->event_limit); | |
8056 | int ret = 0; | |
8057 | ||
8058 | /* | |
8059 | * Non-sampling counters might still use the PMI to fold short | |
8060 | * hardware counters, ignore those. | |
8061 | */ | |
8062 | if (unlikely(!is_sampling_event(event))) | |
8063 | return 0; | |
8064 | ||
8065 | ret = __perf_event_account_interrupt(event, throttle); | |
cc1582c2 | 8066 | |
2023b359 PZ |
8067 | /* |
8068 | * XXX event_limit might not quite work as expected on inherited | |
cdd6c482 | 8069 | * events |
2023b359 PZ |
8070 | */ |
8071 | ||
cdd6c482 IM |
8072 | event->pending_kill = POLL_IN; |
8073 | if (events && atomic_dec_and_test(&event->event_limit)) { | |
79f14641 | 8074 | ret = 1; |
cdd6c482 | 8075 | event->pending_kill = POLL_HUP; |
5aab90ce JO |
8076 | |
8077 | perf_event_disable_inatomic(event); | |
79f14641 PZ |
8078 | } |
8079 | ||
aa6a5f3c | 8080 | READ_ONCE(event->overflow_handler)(event, data, regs); |
453f19ee | 8081 | |
fed66e2c | 8082 | if (*perf_event_fasync(event) && event->pending_kill) { |
a8b0ca17 PZ |
8083 | event->pending_wakeup = 1; |
8084 | irq_work_queue(&event->pending); | |
f506b3dc PZ |
8085 | } |
8086 | ||
79f14641 | 8087 | return ret; |
f6c7d5fe PZ |
8088 | } |
8089 | ||
a8b0ca17 | 8090 | int perf_event_overflow(struct perf_event *event, |
5622f295 MM |
8091 | struct perf_sample_data *data, |
8092 | struct pt_regs *regs) | |
850bc73f | 8093 | { |
a8b0ca17 | 8094 | return __perf_event_overflow(event, 1, data, regs); |
850bc73f PZ |
8095 | } |
8096 | ||
15dbf27c | 8097 | /* |
cdd6c482 | 8098 | * Generic software event infrastructure |
15dbf27c PZ |
8099 | */ |
8100 | ||
b28ab83c PZ |
8101 | struct swevent_htable { |
8102 | struct swevent_hlist *swevent_hlist; | |
8103 | struct mutex hlist_mutex; | |
8104 | int hlist_refcount; | |
8105 | ||
8106 | /* Recursion avoidance in each contexts */ | |
8107 | int recursion[PERF_NR_CONTEXTS]; | |
8108 | }; | |
8109 | ||
8110 | static DEFINE_PER_CPU(struct swevent_htable, swevent_htable); | |
8111 | ||
7b4b6658 | 8112 | /* |
cdd6c482 IM |
8113 | * We directly increment event->count and keep a second value in |
8114 | * event->hw.period_left to count intervals. This period event | |
7b4b6658 PZ |
8115 | * is kept in the range [-sample_period, 0] so that we can use the |
8116 | * sign as trigger. | |
8117 | */ | |
8118 | ||
ab573844 | 8119 | u64 perf_swevent_set_period(struct perf_event *event) |
15dbf27c | 8120 | { |
cdd6c482 | 8121 | struct hw_perf_event *hwc = &event->hw; |
7b4b6658 PZ |
8122 | u64 period = hwc->last_period; |
8123 | u64 nr, offset; | |
8124 | s64 old, val; | |
8125 | ||
8126 | hwc->last_period = hwc->sample_period; | |
15dbf27c PZ |
8127 | |
8128 | again: | |
e7850595 | 8129 | old = val = local64_read(&hwc->period_left); |
7b4b6658 PZ |
8130 | if (val < 0) |
8131 | return 0; | |
15dbf27c | 8132 | |
7b4b6658 PZ |
8133 | nr = div64_u64(period + val, period); |
8134 | offset = nr * period; | |
8135 | val -= offset; | |
e7850595 | 8136 | if (local64_cmpxchg(&hwc->period_left, old, val) != old) |
7b4b6658 | 8137 | goto again; |
15dbf27c | 8138 | |
7b4b6658 | 8139 | return nr; |
15dbf27c PZ |
8140 | } |
8141 | ||
0cff784a | 8142 | static void perf_swevent_overflow(struct perf_event *event, u64 overflow, |
a8b0ca17 | 8143 | struct perf_sample_data *data, |
5622f295 | 8144 | struct pt_regs *regs) |
15dbf27c | 8145 | { |
cdd6c482 | 8146 | struct hw_perf_event *hwc = &event->hw; |
850bc73f | 8147 | int throttle = 0; |
15dbf27c | 8148 | |
0cff784a PZ |
8149 | if (!overflow) |
8150 | overflow = perf_swevent_set_period(event); | |
15dbf27c | 8151 | |
7b4b6658 PZ |
8152 | if (hwc->interrupts == MAX_INTERRUPTS) |
8153 | return; | |
15dbf27c | 8154 | |
7b4b6658 | 8155 | for (; overflow; overflow--) { |
a8b0ca17 | 8156 | if (__perf_event_overflow(event, throttle, |
5622f295 | 8157 | data, regs)) { |
7b4b6658 PZ |
8158 | /* |
8159 | * We inhibit the overflow from happening when | |
8160 | * hwc->interrupts == MAX_INTERRUPTS. | |
8161 | */ | |
8162 | break; | |
8163 | } | |
cf450a73 | 8164 | throttle = 1; |
7b4b6658 | 8165 | } |
15dbf27c PZ |
8166 | } |
8167 | ||
a4eaf7f1 | 8168 | static void perf_swevent_event(struct perf_event *event, u64 nr, |
a8b0ca17 | 8169 | struct perf_sample_data *data, |
5622f295 | 8170 | struct pt_regs *regs) |
7b4b6658 | 8171 | { |
cdd6c482 | 8172 | struct hw_perf_event *hwc = &event->hw; |
d6d020e9 | 8173 | |
e7850595 | 8174 | local64_add(nr, &event->count); |
d6d020e9 | 8175 | |
0cff784a PZ |
8176 | if (!regs) |
8177 | return; | |
8178 | ||
6c7e550f | 8179 | if (!is_sampling_event(event)) |
7b4b6658 | 8180 | return; |
d6d020e9 | 8181 | |
5d81e5cf AV |
8182 | if ((event->attr.sample_type & PERF_SAMPLE_PERIOD) && !event->attr.freq) { |
8183 | data->period = nr; | |
8184 | return perf_swevent_overflow(event, 1, data, regs); | |
8185 | } else | |
8186 | data->period = event->hw.last_period; | |
8187 | ||
0cff784a | 8188 | if (nr == 1 && hwc->sample_period == 1 && !event->attr.freq) |
a8b0ca17 | 8189 | return perf_swevent_overflow(event, 1, data, regs); |
0cff784a | 8190 | |
e7850595 | 8191 | if (local64_add_negative(nr, &hwc->period_left)) |
7b4b6658 | 8192 | return; |
df1a132b | 8193 | |
a8b0ca17 | 8194 | perf_swevent_overflow(event, 0, data, regs); |
d6d020e9 PZ |
8195 | } |
8196 | ||
f5ffe02e FW |
8197 | static int perf_exclude_event(struct perf_event *event, |
8198 | struct pt_regs *regs) | |
8199 | { | |
a4eaf7f1 | 8200 | if (event->hw.state & PERF_HES_STOPPED) |
91b2f482 | 8201 | return 1; |
a4eaf7f1 | 8202 | |
f5ffe02e FW |
8203 | if (regs) { |
8204 | if (event->attr.exclude_user && user_mode(regs)) | |
8205 | return 1; | |
8206 | ||
8207 | if (event->attr.exclude_kernel && !user_mode(regs)) | |
8208 | return 1; | |
8209 | } | |
8210 | ||
8211 | return 0; | |
8212 | } | |
8213 | ||
cdd6c482 | 8214 | static int perf_swevent_match(struct perf_event *event, |
1c432d89 | 8215 | enum perf_type_id type, |
6fb2915d LZ |
8216 | u32 event_id, |
8217 | struct perf_sample_data *data, | |
8218 | struct pt_regs *regs) | |
15dbf27c | 8219 | { |
cdd6c482 | 8220 | if (event->attr.type != type) |
a21ca2ca | 8221 | return 0; |
f5ffe02e | 8222 | |
cdd6c482 | 8223 | if (event->attr.config != event_id) |
15dbf27c PZ |
8224 | return 0; |
8225 | ||
f5ffe02e FW |
8226 | if (perf_exclude_event(event, regs)) |
8227 | return 0; | |
15dbf27c PZ |
8228 | |
8229 | return 1; | |
8230 | } | |
8231 | ||
76e1d904 FW |
8232 | static inline u64 swevent_hash(u64 type, u32 event_id) |
8233 | { | |
8234 | u64 val = event_id | (type << 32); | |
8235 | ||
8236 | return hash_64(val, SWEVENT_HLIST_BITS); | |
8237 | } | |
8238 | ||
49f135ed FW |
8239 | static inline struct hlist_head * |
8240 | __find_swevent_head(struct swevent_hlist *hlist, u64 type, u32 event_id) | |
76e1d904 | 8241 | { |
49f135ed FW |
8242 | u64 hash = swevent_hash(type, event_id); |
8243 | ||
8244 | return &hlist->heads[hash]; | |
8245 | } | |
76e1d904 | 8246 | |
49f135ed FW |
8247 | /* For the read side: events when they trigger */ |
8248 | static inline struct hlist_head * | |
b28ab83c | 8249 | find_swevent_head_rcu(struct swevent_htable *swhash, u64 type, u32 event_id) |
49f135ed FW |
8250 | { |
8251 | struct swevent_hlist *hlist; | |
76e1d904 | 8252 | |
b28ab83c | 8253 | hlist = rcu_dereference(swhash->swevent_hlist); |
76e1d904 FW |
8254 | if (!hlist) |
8255 | return NULL; | |
8256 | ||
49f135ed FW |
8257 | return __find_swevent_head(hlist, type, event_id); |
8258 | } | |
8259 | ||
8260 | /* For the event head insertion and removal in the hlist */ | |
8261 | static inline struct hlist_head * | |
b28ab83c | 8262 | find_swevent_head(struct swevent_htable *swhash, struct perf_event *event) |
49f135ed FW |
8263 | { |
8264 | struct swevent_hlist *hlist; | |
8265 | u32 event_id = event->attr.config; | |
8266 | u64 type = event->attr.type; | |
8267 | ||
8268 | /* | |
8269 | * Event scheduling is always serialized against hlist allocation | |
8270 | * and release. Which makes the protected version suitable here. | |
8271 | * The context lock guarantees that. | |
8272 | */ | |
b28ab83c | 8273 | hlist = rcu_dereference_protected(swhash->swevent_hlist, |
49f135ed FW |
8274 | lockdep_is_held(&event->ctx->lock)); |
8275 | if (!hlist) | |
8276 | return NULL; | |
8277 | ||
8278 | return __find_swevent_head(hlist, type, event_id); | |
76e1d904 FW |
8279 | } |
8280 | ||
8281 | static void do_perf_sw_event(enum perf_type_id type, u32 event_id, | |
a8b0ca17 | 8282 | u64 nr, |
76e1d904 FW |
8283 | struct perf_sample_data *data, |
8284 | struct pt_regs *regs) | |
15dbf27c | 8285 | { |
4a32fea9 | 8286 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 8287 | struct perf_event *event; |
76e1d904 | 8288 | struct hlist_head *head; |
15dbf27c | 8289 | |
76e1d904 | 8290 | rcu_read_lock(); |
b28ab83c | 8291 | head = find_swevent_head_rcu(swhash, type, event_id); |
76e1d904 FW |
8292 | if (!head) |
8293 | goto end; | |
8294 | ||
b67bfe0d | 8295 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
6fb2915d | 8296 | if (perf_swevent_match(event, type, event_id, data, regs)) |
a8b0ca17 | 8297 | perf_swevent_event(event, nr, data, regs); |
15dbf27c | 8298 | } |
76e1d904 FW |
8299 | end: |
8300 | rcu_read_unlock(); | |
15dbf27c PZ |
8301 | } |
8302 | ||
86038c5e PZI |
8303 | DEFINE_PER_CPU(struct pt_regs, __perf_regs[4]); |
8304 | ||
4ed7c92d | 8305 | int perf_swevent_get_recursion_context(void) |
96f6d444 | 8306 | { |
4a32fea9 | 8307 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
96f6d444 | 8308 | |
b28ab83c | 8309 | return get_recursion_context(swhash->recursion); |
96f6d444 | 8310 | } |
645e8cc0 | 8311 | EXPORT_SYMBOL_GPL(perf_swevent_get_recursion_context); |
96f6d444 | 8312 | |
98b5c2c6 | 8313 | void perf_swevent_put_recursion_context(int rctx) |
15dbf27c | 8314 | { |
4a32fea9 | 8315 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
927c7a9e | 8316 | |
b28ab83c | 8317 | put_recursion_context(swhash->recursion, rctx); |
ce71b9df | 8318 | } |
15dbf27c | 8319 | |
86038c5e | 8320 | void ___perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) |
b8e83514 | 8321 | { |
a4234bfc | 8322 | struct perf_sample_data data; |
4ed7c92d | 8323 | |
86038c5e | 8324 | if (WARN_ON_ONCE(!regs)) |
4ed7c92d | 8325 | return; |
a4234bfc | 8326 | |
fd0d000b | 8327 | perf_sample_data_init(&data, addr, 0); |
a8b0ca17 | 8328 | do_perf_sw_event(PERF_TYPE_SOFTWARE, event_id, nr, &data, regs); |
86038c5e PZI |
8329 | } |
8330 | ||
8331 | void __perf_sw_event(u32 event_id, u64 nr, struct pt_regs *regs, u64 addr) | |
8332 | { | |
8333 | int rctx; | |
8334 | ||
8335 | preempt_disable_notrace(); | |
8336 | rctx = perf_swevent_get_recursion_context(); | |
8337 | if (unlikely(rctx < 0)) | |
8338 | goto fail; | |
8339 | ||
8340 | ___perf_sw_event(event_id, nr, regs, addr); | |
4ed7c92d PZ |
8341 | |
8342 | perf_swevent_put_recursion_context(rctx); | |
86038c5e | 8343 | fail: |
1c024eca | 8344 | preempt_enable_notrace(); |
b8e83514 PZ |
8345 | } |
8346 | ||
cdd6c482 | 8347 | static void perf_swevent_read(struct perf_event *event) |
15dbf27c | 8348 | { |
15dbf27c PZ |
8349 | } |
8350 | ||
a4eaf7f1 | 8351 | static int perf_swevent_add(struct perf_event *event, int flags) |
15dbf27c | 8352 | { |
4a32fea9 | 8353 | struct swevent_htable *swhash = this_cpu_ptr(&swevent_htable); |
cdd6c482 | 8354 | struct hw_perf_event *hwc = &event->hw; |
76e1d904 FW |
8355 | struct hlist_head *head; |
8356 | ||
6c7e550f | 8357 | if (is_sampling_event(event)) { |
7b4b6658 | 8358 | hwc->last_period = hwc->sample_period; |
cdd6c482 | 8359 | perf_swevent_set_period(event); |
7b4b6658 | 8360 | } |
76e1d904 | 8361 | |
a4eaf7f1 PZ |
8362 | hwc->state = !(flags & PERF_EF_START); |
8363 | ||
b28ab83c | 8364 | head = find_swevent_head(swhash, event); |
12ca6ad2 | 8365 | if (WARN_ON_ONCE(!head)) |
76e1d904 FW |
8366 | return -EINVAL; |
8367 | ||
8368 | hlist_add_head_rcu(&event->hlist_entry, head); | |
6a694a60 | 8369 | perf_event_update_userpage(event); |
76e1d904 | 8370 | |
15dbf27c PZ |
8371 | return 0; |
8372 | } | |
8373 | ||
a4eaf7f1 | 8374 | static void perf_swevent_del(struct perf_event *event, int flags) |
15dbf27c | 8375 | { |
76e1d904 | 8376 | hlist_del_rcu(&event->hlist_entry); |
15dbf27c PZ |
8377 | } |
8378 | ||
a4eaf7f1 | 8379 | static void perf_swevent_start(struct perf_event *event, int flags) |
5c92d124 | 8380 | { |
a4eaf7f1 | 8381 | event->hw.state = 0; |
d6d020e9 | 8382 | } |
aa9c4c0f | 8383 | |
a4eaf7f1 | 8384 | static void perf_swevent_stop(struct perf_event *event, int flags) |
d6d020e9 | 8385 | { |
a4eaf7f1 | 8386 | event->hw.state = PERF_HES_STOPPED; |
bae43c99 IM |
8387 | } |
8388 | ||
49f135ed FW |
8389 | /* Deref the hlist from the update side */ |
8390 | static inline struct swevent_hlist * | |
b28ab83c | 8391 | swevent_hlist_deref(struct swevent_htable *swhash) |
49f135ed | 8392 | { |
b28ab83c PZ |
8393 | return rcu_dereference_protected(swhash->swevent_hlist, |
8394 | lockdep_is_held(&swhash->hlist_mutex)); | |
49f135ed FW |
8395 | } |
8396 | ||
b28ab83c | 8397 | static void swevent_hlist_release(struct swevent_htable *swhash) |
76e1d904 | 8398 | { |
b28ab83c | 8399 | struct swevent_hlist *hlist = swevent_hlist_deref(swhash); |
76e1d904 | 8400 | |
49f135ed | 8401 | if (!hlist) |
76e1d904 FW |
8402 | return; |
8403 | ||
70691d4a | 8404 | RCU_INIT_POINTER(swhash->swevent_hlist, NULL); |
fa4bbc4c | 8405 | kfree_rcu(hlist, rcu_head); |
76e1d904 FW |
8406 | } |
8407 | ||
3b364d7b | 8408 | static void swevent_hlist_put_cpu(int cpu) |
76e1d904 | 8409 | { |
b28ab83c | 8410 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 | 8411 | |
b28ab83c | 8412 | mutex_lock(&swhash->hlist_mutex); |
76e1d904 | 8413 | |
b28ab83c PZ |
8414 | if (!--swhash->hlist_refcount) |
8415 | swevent_hlist_release(swhash); | |
76e1d904 | 8416 | |
b28ab83c | 8417 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
8418 | } |
8419 | ||
3b364d7b | 8420 | static void swevent_hlist_put(void) |
76e1d904 FW |
8421 | { |
8422 | int cpu; | |
8423 | ||
76e1d904 | 8424 | for_each_possible_cpu(cpu) |
3b364d7b | 8425 | swevent_hlist_put_cpu(cpu); |
76e1d904 FW |
8426 | } |
8427 | ||
3b364d7b | 8428 | static int swevent_hlist_get_cpu(int cpu) |
76e1d904 | 8429 | { |
b28ab83c | 8430 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
76e1d904 FW |
8431 | int err = 0; |
8432 | ||
b28ab83c | 8433 | mutex_lock(&swhash->hlist_mutex); |
a63fbed7 TG |
8434 | if (!swevent_hlist_deref(swhash) && |
8435 | cpumask_test_cpu(cpu, perf_online_mask)) { | |
76e1d904 FW |
8436 | struct swevent_hlist *hlist; |
8437 | ||
8438 | hlist = kzalloc(sizeof(*hlist), GFP_KERNEL); | |
8439 | if (!hlist) { | |
8440 | err = -ENOMEM; | |
8441 | goto exit; | |
8442 | } | |
b28ab83c | 8443 | rcu_assign_pointer(swhash->swevent_hlist, hlist); |
76e1d904 | 8444 | } |
b28ab83c | 8445 | swhash->hlist_refcount++; |
9ed6060d | 8446 | exit: |
b28ab83c | 8447 | mutex_unlock(&swhash->hlist_mutex); |
76e1d904 FW |
8448 | |
8449 | return err; | |
8450 | } | |
8451 | ||
3b364d7b | 8452 | static int swevent_hlist_get(void) |
76e1d904 | 8453 | { |
3b364d7b | 8454 | int err, cpu, failed_cpu; |
76e1d904 | 8455 | |
a63fbed7 | 8456 | mutex_lock(&pmus_lock); |
76e1d904 | 8457 | for_each_possible_cpu(cpu) { |
3b364d7b | 8458 | err = swevent_hlist_get_cpu(cpu); |
76e1d904 FW |
8459 | if (err) { |
8460 | failed_cpu = cpu; | |
8461 | goto fail; | |
8462 | } | |
8463 | } | |
a63fbed7 | 8464 | mutex_unlock(&pmus_lock); |
76e1d904 | 8465 | return 0; |
9ed6060d | 8466 | fail: |
76e1d904 FW |
8467 | for_each_possible_cpu(cpu) { |
8468 | if (cpu == failed_cpu) | |
8469 | break; | |
3b364d7b | 8470 | swevent_hlist_put_cpu(cpu); |
76e1d904 | 8471 | } |
a63fbed7 | 8472 | mutex_unlock(&pmus_lock); |
76e1d904 FW |
8473 | return err; |
8474 | } | |
8475 | ||
c5905afb | 8476 | struct static_key perf_swevent_enabled[PERF_COUNT_SW_MAX]; |
95476b64 | 8477 | |
b0a873eb PZ |
8478 | static void sw_perf_event_destroy(struct perf_event *event) |
8479 | { | |
8480 | u64 event_id = event->attr.config; | |
95476b64 | 8481 | |
b0a873eb PZ |
8482 | WARN_ON(event->parent); |
8483 | ||
c5905afb | 8484 | static_key_slow_dec(&perf_swevent_enabled[event_id]); |
3b364d7b | 8485 | swevent_hlist_put(); |
b0a873eb PZ |
8486 | } |
8487 | ||
8488 | static int perf_swevent_init(struct perf_event *event) | |
8489 | { | |
8176cced | 8490 | u64 event_id = event->attr.config; |
b0a873eb PZ |
8491 | |
8492 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
8493 | return -ENOENT; | |
8494 | ||
2481c5fa SE |
8495 | /* |
8496 | * no branch sampling for software events | |
8497 | */ | |
8498 | if (has_branch_stack(event)) | |
8499 | return -EOPNOTSUPP; | |
8500 | ||
b0a873eb PZ |
8501 | switch (event_id) { |
8502 | case PERF_COUNT_SW_CPU_CLOCK: | |
8503 | case PERF_COUNT_SW_TASK_CLOCK: | |
8504 | return -ENOENT; | |
8505 | ||
8506 | default: | |
8507 | break; | |
8508 | } | |
8509 | ||
ce677831 | 8510 | if (event_id >= PERF_COUNT_SW_MAX) |
b0a873eb PZ |
8511 | return -ENOENT; |
8512 | ||
8513 | if (!event->parent) { | |
8514 | int err; | |
8515 | ||
3b364d7b | 8516 | err = swevent_hlist_get(); |
b0a873eb PZ |
8517 | if (err) |
8518 | return err; | |
8519 | ||
c5905afb | 8520 | static_key_slow_inc(&perf_swevent_enabled[event_id]); |
b0a873eb PZ |
8521 | event->destroy = sw_perf_event_destroy; |
8522 | } | |
8523 | ||
8524 | return 0; | |
8525 | } | |
8526 | ||
8527 | static struct pmu perf_swevent = { | |
89a1e187 | 8528 | .task_ctx_nr = perf_sw_context, |
95476b64 | 8529 | |
34f43927 PZ |
8530 | .capabilities = PERF_PMU_CAP_NO_NMI, |
8531 | ||
b0a873eb | 8532 | .event_init = perf_swevent_init, |
a4eaf7f1 PZ |
8533 | .add = perf_swevent_add, |
8534 | .del = perf_swevent_del, | |
8535 | .start = perf_swevent_start, | |
8536 | .stop = perf_swevent_stop, | |
1c024eca | 8537 | .read = perf_swevent_read, |
1c024eca PZ |
8538 | }; |
8539 | ||
b0a873eb PZ |
8540 | #ifdef CONFIG_EVENT_TRACING |
8541 | ||
1c024eca PZ |
8542 | static int perf_tp_filter_match(struct perf_event *event, |
8543 | struct perf_sample_data *data) | |
8544 | { | |
7e3f977e | 8545 | void *record = data->raw->frag.data; |
1c024eca | 8546 | |
b71b437e PZ |
8547 | /* only top level events have filters set */ |
8548 | if (event->parent) | |
8549 | event = event->parent; | |
8550 | ||
1c024eca PZ |
8551 | if (likely(!event->filter) || filter_match_preds(event->filter, record)) |
8552 | return 1; | |
8553 | return 0; | |
8554 | } | |
8555 | ||
8556 | static int perf_tp_event_match(struct perf_event *event, | |
8557 | struct perf_sample_data *data, | |
8558 | struct pt_regs *regs) | |
8559 | { | |
a0f7d0f7 FW |
8560 | if (event->hw.state & PERF_HES_STOPPED) |
8561 | return 0; | |
580d607c | 8562 | /* |
9fd2e48b | 8563 | * If exclude_kernel, only trace user-space tracepoints (uprobes) |
580d607c | 8564 | */ |
9fd2e48b | 8565 | if (event->attr.exclude_kernel && !user_mode(regs)) |
1c024eca PZ |
8566 | return 0; |
8567 | ||
8568 | if (!perf_tp_filter_match(event, data)) | |
8569 | return 0; | |
8570 | ||
8571 | return 1; | |
8572 | } | |
8573 | ||
85b67bcb AS |
8574 | void perf_trace_run_bpf_submit(void *raw_data, int size, int rctx, |
8575 | struct trace_event_call *call, u64 count, | |
8576 | struct pt_regs *regs, struct hlist_head *head, | |
8577 | struct task_struct *task) | |
8578 | { | |
e87c6bc3 | 8579 | if (bpf_prog_array_valid(call)) { |
85b67bcb | 8580 | *(struct pt_regs **)raw_data = regs; |
e87c6bc3 | 8581 | if (!trace_call_bpf(call, raw_data) || hlist_empty(head)) { |
85b67bcb AS |
8582 | perf_swevent_put_recursion_context(rctx); |
8583 | return; | |
8584 | } | |
8585 | } | |
8586 | perf_tp_event(call->event.type, count, raw_data, size, regs, head, | |
8fd0fbbe | 8587 | rctx, task); |
85b67bcb AS |
8588 | } |
8589 | EXPORT_SYMBOL_GPL(perf_trace_run_bpf_submit); | |
8590 | ||
1e1dcd93 | 8591 | void perf_tp_event(u16 event_type, u64 count, void *record, int entry_size, |
e6dab5ff | 8592 | struct pt_regs *regs, struct hlist_head *head, int rctx, |
8fd0fbbe | 8593 | struct task_struct *task) |
95476b64 FW |
8594 | { |
8595 | struct perf_sample_data data; | |
8fd0fbbe | 8596 | struct perf_event *event; |
1c024eca | 8597 | |
95476b64 | 8598 | struct perf_raw_record raw = { |
7e3f977e DB |
8599 | .frag = { |
8600 | .size = entry_size, | |
8601 | .data = record, | |
8602 | }, | |
95476b64 FW |
8603 | }; |
8604 | ||
1e1dcd93 | 8605 | perf_sample_data_init(&data, 0, 0); |
95476b64 FW |
8606 | data.raw = &raw; |
8607 | ||
1e1dcd93 AS |
8608 | perf_trace_buf_update(record, event_type); |
8609 | ||
8fd0fbbe | 8610 | hlist_for_each_entry_rcu(event, head, hlist_entry) { |
1c024eca | 8611 | if (perf_tp_event_match(event, &data, regs)) |
a8b0ca17 | 8612 | perf_swevent_event(event, count, &data, regs); |
4f41c013 | 8613 | } |
ecc55f84 | 8614 | |
e6dab5ff AV |
8615 | /* |
8616 | * If we got specified a target task, also iterate its context and | |
8617 | * deliver this event there too. | |
8618 | */ | |
8619 | if (task && task != current) { | |
8620 | struct perf_event_context *ctx; | |
8621 | struct trace_entry *entry = record; | |
8622 | ||
8623 | rcu_read_lock(); | |
8624 | ctx = rcu_dereference(task->perf_event_ctxp[perf_sw_context]); | |
8625 | if (!ctx) | |
8626 | goto unlock; | |
8627 | ||
8628 | list_for_each_entry_rcu(event, &ctx->event_list, event_entry) { | |
cd6fb677 JO |
8629 | if (event->cpu != smp_processor_id()) |
8630 | continue; | |
e6dab5ff AV |
8631 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
8632 | continue; | |
8633 | if (event->attr.config != entry->type) | |
8634 | continue; | |
8635 | if (perf_tp_event_match(event, &data, regs)) | |
8636 | perf_swevent_event(event, count, &data, regs); | |
8637 | } | |
8638 | unlock: | |
8639 | rcu_read_unlock(); | |
8640 | } | |
8641 | ||
ecc55f84 | 8642 | perf_swevent_put_recursion_context(rctx); |
95476b64 FW |
8643 | } |
8644 | EXPORT_SYMBOL_GPL(perf_tp_event); | |
8645 | ||
cdd6c482 | 8646 | static void tp_perf_event_destroy(struct perf_event *event) |
e077df4f | 8647 | { |
1c024eca | 8648 | perf_trace_destroy(event); |
e077df4f PZ |
8649 | } |
8650 | ||
b0a873eb | 8651 | static int perf_tp_event_init(struct perf_event *event) |
e077df4f | 8652 | { |
76e1d904 FW |
8653 | int err; |
8654 | ||
b0a873eb PZ |
8655 | if (event->attr.type != PERF_TYPE_TRACEPOINT) |
8656 | return -ENOENT; | |
8657 | ||
2481c5fa SE |
8658 | /* |
8659 | * no branch sampling for tracepoint events | |
8660 | */ | |
8661 | if (has_branch_stack(event)) | |
8662 | return -EOPNOTSUPP; | |
8663 | ||
1c024eca PZ |
8664 | err = perf_trace_init(event); |
8665 | if (err) | |
b0a873eb | 8666 | return err; |
e077df4f | 8667 | |
cdd6c482 | 8668 | event->destroy = tp_perf_event_destroy; |
e077df4f | 8669 | |
b0a873eb PZ |
8670 | return 0; |
8671 | } | |
8672 | ||
8673 | static struct pmu perf_tracepoint = { | |
89a1e187 PZ |
8674 | .task_ctx_nr = perf_sw_context, |
8675 | ||
b0a873eb | 8676 | .event_init = perf_tp_event_init, |
a4eaf7f1 PZ |
8677 | .add = perf_trace_add, |
8678 | .del = perf_trace_del, | |
8679 | .start = perf_swevent_start, | |
8680 | .stop = perf_swevent_stop, | |
b0a873eb | 8681 | .read = perf_swevent_read, |
b0a873eb PZ |
8682 | }; |
8683 | ||
33ea4b24 | 8684 | #if defined(CONFIG_KPROBE_EVENTS) || defined(CONFIG_UPROBE_EVENTS) |
e12f03d7 SL |
8685 | /* |
8686 | * Flags in config, used by dynamic PMU kprobe and uprobe | |
8687 | * The flags should match following PMU_FORMAT_ATTR(). | |
8688 | * | |
8689 | * PERF_PROBE_CONFIG_IS_RETPROBE if set, create kretprobe/uretprobe | |
8690 | * if not set, create kprobe/uprobe | |
a6ca88b2 SL |
8691 | * |
8692 | * The following values specify a reference counter (or semaphore in the | |
8693 | * terminology of tools like dtrace, systemtap, etc.) Userspace Statically | |
8694 | * Defined Tracepoints (USDT). Currently, we use 40 bit for the offset. | |
8695 | * | |
8696 | * PERF_UPROBE_REF_CTR_OFFSET_BITS # of bits in config as th offset | |
8697 | * PERF_UPROBE_REF_CTR_OFFSET_SHIFT # of bits to shift left | |
e12f03d7 SL |
8698 | */ |
8699 | enum perf_probe_config { | |
8700 | PERF_PROBE_CONFIG_IS_RETPROBE = 1U << 0, /* [k,u]retprobe */ | |
a6ca88b2 SL |
8701 | PERF_UPROBE_REF_CTR_OFFSET_BITS = 32, |
8702 | PERF_UPROBE_REF_CTR_OFFSET_SHIFT = 64 - PERF_UPROBE_REF_CTR_OFFSET_BITS, | |
e12f03d7 SL |
8703 | }; |
8704 | ||
8705 | PMU_FORMAT_ATTR(retprobe, "config:0"); | |
a6ca88b2 | 8706 | #endif |
e12f03d7 | 8707 | |
a6ca88b2 SL |
8708 | #ifdef CONFIG_KPROBE_EVENTS |
8709 | static struct attribute *kprobe_attrs[] = { | |
e12f03d7 SL |
8710 | &format_attr_retprobe.attr, |
8711 | NULL, | |
8712 | }; | |
8713 | ||
a6ca88b2 | 8714 | static struct attribute_group kprobe_format_group = { |
e12f03d7 | 8715 | .name = "format", |
a6ca88b2 | 8716 | .attrs = kprobe_attrs, |
e12f03d7 SL |
8717 | }; |
8718 | ||
a6ca88b2 SL |
8719 | static const struct attribute_group *kprobe_attr_groups[] = { |
8720 | &kprobe_format_group, | |
e12f03d7 SL |
8721 | NULL, |
8722 | }; | |
8723 | ||
8724 | static int perf_kprobe_event_init(struct perf_event *event); | |
8725 | static struct pmu perf_kprobe = { | |
8726 | .task_ctx_nr = perf_sw_context, | |
8727 | .event_init = perf_kprobe_event_init, | |
8728 | .add = perf_trace_add, | |
8729 | .del = perf_trace_del, | |
8730 | .start = perf_swevent_start, | |
8731 | .stop = perf_swevent_stop, | |
8732 | .read = perf_swevent_read, | |
a6ca88b2 | 8733 | .attr_groups = kprobe_attr_groups, |
e12f03d7 SL |
8734 | }; |
8735 | ||
8736 | static int perf_kprobe_event_init(struct perf_event *event) | |
8737 | { | |
8738 | int err; | |
8739 | bool is_retprobe; | |
8740 | ||
8741 | if (event->attr.type != perf_kprobe.type) | |
8742 | return -ENOENT; | |
32e6e967 SL |
8743 | |
8744 | if (!capable(CAP_SYS_ADMIN)) | |
8745 | return -EACCES; | |
8746 | ||
e12f03d7 SL |
8747 | /* |
8748 | * no branch sampling for probe events | |
8749 | */ | |
8750 | if (has_branch_stack(event)) | |
8751 | return -EOPNOTSUPP; | |
8752 | ||
8753 | is_retprobe = event->attr.config & PERF_PROBE_CONFIG_IS_RETPROBE; | |
8754 | err = perf_kprobe_init(event, is_retprobe); | |
8755 | if (err) | |
8756 | return err; | |
8757 | ||
8758 | event->destroy = perf_kprobe_destroy; | |
8759 | ||
8760 | return 0; | |
8761 | } | |
8762 | #endif /* CONFIG_KPROBE_EVENTS */ | |
8763 | ||
33ea4b24 | 8764 | #ifdef CONFIG_UPROBE_EVENTS |
a6ca88b2 SL |
8765 | PMU_FORMAT_ATTR(ref_ctr_offset, "config:32-63"); |
8766 | ||
8767 | static struct attribute *uprobe_attrs[] = { | |
8768 | &format_attr_retprobe.attr, | |
8769 | &format_attr_ref_ctr_offset.attr, | |
8770 | NULL, | |
8771 | }; | |
8772 | ||
8773 | static struct attribute_group uprobe_format_group = { | |
8774 | .name = "format", | |
8775 | .attrs = uprobe_attrs, | |
8776 | }; | |
8777 | ||
8778 | static const struct attribute_group *uprobe_attr_groups[] = { | |
8779 | &uprobe_format_group, | |
8780 | NULL, | |
8781 | }; | |
8782 | ||
33ea4b24 SL |
8783 | static int perf_uprobe_event_init(struct perf_event *event); |
8784 | static struct pmu perf_uprobe = { | |
8785 | .task_ctx_nr = perf_sw_context, | |
8786 | .event_init = perf_uprobe_event_init, | |
8787 | .add = perf_trace_add, | |
8788 | .del = perf_trace_del, | |
8789 | .start = perf_swevent_start, | |
8790 | .stop = perf_swevent_stop, | |
8791 | .read = perf_swevent_read, | |
a6ca88b2 | 8792 | .attr_groups = uprobe_attr_groups, |
33ea4b24 SL |
8793 | }; |
8794 | ||
8795 | static int perf_uprobe_event_init(struct perf_event *event) | |
8796 | { | |
8797 | int err; | |
a6ca88b2 | 8798 | unsigned long ref_ctr_offset; |
33ea4b24 SL |
8799 | bool is_retprobe; |
8800 | ||
8801 | if (event->attr.type != perf_uprobe.type) | |
8802 | return -ENOENT; | |
32e6e967 SL |
8803 | |
8804 | if (!capable(CAP_SYS_ADMIN)) | |
8805 | return -EACCES; | |
8806 | ||
33ea4b24 SL |
8807 | /* |
8808 | * no branch sampling for probe events | |
8809 | */ | |
8810 | if (has_branch_stack(event)) | |
8811 | return -EOPNOTSUPP; | |
8812 | ||
8813 | is_retprobe = event->attr.config & PERF_PROBE_CONFIG_IS_RETPROBE; | |
a6ca88b2 SL |
8814 | ref_ctr_offset = event->attr.config >> PERF_UPROBE_REF_CTR_OFFSET_SHIFT; |
8815 | err = perf_uprobe_init(event, ref_ctr_offset, is_retprobe); | |
33ea4b24 SL |
8816 | if (err) |
8817 | return err; | |
8818 | ||
8819 | event->destroy = perf_uprobe_destroy; | |
8820 | ||
8821 | return 0; | |
8822 | } | |
8823 | #endif /* CONFIG_UPROBE_EVENTS */ | |
8824 | ||
b0a873eb PZ |
8825 | static inline void perf_tp_register(void) |
8826 | { | |
2e80a82a | 8827 | perf_pmu_register(&perf_tracepoint, "tracepoint", PERF_TYPE_TRACEPOINT); |
e12f03d7 SL |
8828 | #ifdef CONFIG_KPROBE_EVENTS |
8829 | perf_pmu_register(&perf_kprobe, "kprobe", -1); | |
8830 | #endif | |
33ea4b24 SL |
8831 | #ifdef CONFIG_UPROBE_EVENTS |
8832 | perf_pmu_register(&perf_uprobe, "uprobe", -1); | |
8833 | #endif | |
e077df4f | 8834 | } |
6fb2915d | 8835 | |
6fb2915d LZ |
8836 | static void perf_event_free_filter(struct perf_event *event) |
8837 | { | |
8838 | ftrace_profile_free_filter(event); | |
8839 | } | |
8840 | ||
aa6a5f3c AS |
8841 | #ifdef CONFIG_BPF_SYSCALL |
8842 | static void bpf_overflow_handler(struct perf_event *event, | |
8843 | struct perf_sample_data *data, | |
8844 | struct pt_regs *regs) | |
8845 | { | |
8846 | struct bpf_perf_event_data_kern ctx = { | |
8847 | .data = data, | |
7d9285e8 | 8848 | .event = event, |
aa6a5f3c AS |
8849 | }; |
8850 | int ret = 0; | |
8851 | ||
c895f6f7 | 8852 | ctx.regs = perf_arch_bpf_user_pt_regs(regs); |
aa6a5f3c AS |
8853 | preempt_disable(); |
8854 | if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) | |
8855 | goto out; | |
8856 | rcu_read_lock(); | |
88575199 | 8857 | ret = BPF_PROG_RUN(event->prog, &ctx); |
aa6a5f3c AS |
8858 | rcu_read_unlock(); |
8859 | out: | |
8860 | __this_cpu_dec(bpf_prog_active); | |
8861 | preempt_enable(); | |
8862 | if (!ret) | |
8863 | return; | |
8864 | ||
8865 | event->orig_overflow_handler(event, data, regs); | |
8866 | } | |
8867 | ||
8868 | static int perf_event_set_bpf_handler(struct perf_event *event, u32 prog_fd) | |
8869 | { | |
8870 | struct bpf_prog *prog; | |
8871 | ||
8872 | if (event->overflow_handler_context) | |
8873 | /* hw breakpoint or kernel counter */ | |
8874 | return -EINVAL; | |
8875 | ||
8876 | if (event->prog) | |
8877 | return -EEXIST; | |
8878 | ||
8879 | prog = bpf_prog_get_type(prog_fd, BPF_PROG_TYPE_PERF_EVENT); | |
8880 | if (IS_ERR(prog)) | |
8881 | return PTR_ERR(prog); | |
8882 | ||
8883 | event->prog = prog; | |
8884 | event->orig_overflow_handler = READ_ONCE(event->overflow_handler); | |
8885 | WRITE_ONCE(event->overflow_handler, bpf_overflow_handler); | |
8886 | return 0; | |
8887 | } | |
8888 | ||
8889 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
8890 | { | |
8891 | struct bpf_prog *prog = event->prog; | |
8892 | ||
8893 | if (!prog) | |
8894 | return; | |
8895 | ||
8896 | WRITE_ONCE(event->overflow_handler, event->orig_overflow_handler); | |
8897 | event->prog = NULL; | |
8898 | bpf_prog_put(prog); | |
8899 | } | |
8900 | #else | |
8901 | static int perf_event_set_bpf_handler(struct perf_event *event, u32 prog_fd) | |
8902 | { | |
8903 | return -EOPNOTSUPP; | |
8904 | } | |
8905 | static void perf_event_free_bpf_handler(struct perf_event *event) | |
8906 | { | |
8907 | } | |
8908 | #endif | |
8909 | ||
e12f03d7 SL |
8910 | /* |
8911 | * returns true if the event is a tracepoint, or a kprobe/upprobe created | |
8912 | * with perf_event_open() | |
8913 | */ | |
8914 | static inline bool perf_event_is_tracing(struct perf_event *event) | |
8915 | { | |
8916 | if (event->pmu == &perf_tracepoint) | |
8917 | return true; | |
8918 | #ifdef CONFIG_KPROBE_EVENTS | |
8919 | if (event->pmu == &perf_kprobe) | |
8920 | return true; | |
33ea4b24 SL |
8921 | #endif |
8922 | #ifdef CONFIG_UPROBE_EVENTS | |
8923 | if (event->pmu == &perf_uprobe) | |
8924 | return true; | |
e12f03d7 SL |
8925 | #endif |
8926 | return false; | |
8927 | } | |
8928 | ||
2541517c AS |
8929 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
8930 | { | |
cf5f5cea | 8931 | bool is_kprobe, is_tracepoint, is_syscall_tp; |
2541517c | 8932 | struct bpf_prog *prog; |
e87c6bc3 | 8933 | int ret; |
2541517c | 8934 | |
e12f03d7 | 8935 | if (!perf_event_is_tracing(event)) |
f91840a3 | 8936 | return perf_event_set_bpf_handler(event, prog_fd); |
2541517c | 8937 | |
98b5c2c6 AS |
8938 | is_kprobe = event->tp_event->flags & TRACE_EVENT_FL_UKPROBE; |
8939 | is_tracepoint = event->tp_event->flags & TRACE_EVENT_FL_TRACEPOINT; | |
cf5f5cea YS |
8940 | is_syscall_tp = is_syscall_trace_event(event->tp_event); |
8941 | if (!is_kprobe && !is_tracepoint && !is_syscall_tp) | |
98b5c2c6 | 8942 | /* bpf programs can only be attached to u/kprobe or tracepoint */ |
2541517c AS |
8943 | return -EINVAL; |
8944 | ||
8945 | prog = bpf_prog_get(prog_fd); | |
8946 | if (IS_ERR(prog)) | |
8947 | return PTR_ERR(prog); | |
8948 | ||
98b5c2c6 | 8949 | if ((is_kprobe && prog->type != BPF_PROG_TYPE_KPROBE) || |
cf5f5cea YS |
8950 | (is_tracepoint && prog->type != BPF_PROG_TYPE_TRACEPOINT) || |
8951 | (is_syscall_tp && prog->type != BPF_PROG_TYPE_TRACEPOINT)) { | |
2541517c AS |
8952 | /* valid fd, but invalid bpf program type */ |
8953 | bpf_prog_put(prog); | |
8954 | return -EINVAL; | |
8955 | } | |
8956 | ||
9802d865 JB |
8957 | /* Kprobe override only works for kprobes, not uprobes. */ |
8958 | if (prog->kprobe_override && | |
8959 | !(event->tp_event->flags & TRACE_EVENT_FL_KPROBE)) { | |
8960 | bpf_prog_put(prog); | |
8961 | return -EINVAL; | |
8962 | } | |
8963 | ||
cf5f5cea | 8964 | if (is_tracepoint || is_syscall_tp) { |
32bbe007 AS |
8965 | int off = trace_event_get_offsets(event->tp_event); |
8966 | ||
8967 | if (prog->aux->max_ctx_offset > off) { | |
8968 | bpf_prog_put(prog); | |
8969 | return -EACCES; | |
8970 | } | |
8971 | } | |
2541517c | 8972 | |
e87c6bc3 YS |
8973 | ret = perf_event_attach_bpf_prog(event, prog); |
8974 | if (ret) | |
8975 | bpf_prog_put(prog); | |
8976 | return ret; | |
2541517c AS |
8977 | } |
8978 | ||
8979 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
8980 | { | |
e12f03d7 | 8981 | if (!perf_event_is_tracing(event)) { |
0b4c6841 | 8982 | perf_event_free_bpf_handler(event); |
2541517c | 8983 | return; |
2541517c | 8984 | } |
e87c6bc3 | 8985 | perf_event_detach_bpf_prog(event); |
2541517c AS |
8986 | } |
8987 | ||
e077df4f | 8988 | #else |
6fb2915d | 8989 | |
b0a873eb | 8990 | static inline void perf_tp_register(void) |
e077df4f | 8991 | { |
e077df4f | 8992 | } |
6fb2915d | 8993 | |
6fb2915d LZ |
8994 | static void perf_event_free_filter(struct perf_event *event) |
8995 | { | |
8996 | } | |
8997 | ||
2541517c AS |
8998 | static int perf_event_set_bpf_prog(struct perf_event *event, u32 prog_fd) |
8999 | { | |
9000 | return -ENOENT; | |
9001 | } | |
9002 | ||
9003 | static void perf_event_free_bpf_prog(struct perf_event *event) | |
9004 | { | |
9005 | } | |
07b139c8 | 9006 | #endif /* CONFIG_EVENT_TRACING */ |
e077df4f | 9007 | |
24f1e32c | 9008 | #ifdef CONFIG_HAVE_HW_BREAKPOINT |
f5ffe02e | 9009 | void perf_bp_event(struct perf_event *bp, void *data) |
24f1e32c | 9010 | { |
f5ffe02e FW |
9011 | struct perf_sample_data sample; |
9012 | struct pt_regs *regs = data; | |
9013 | ||
fd0d000b | 9014 | perf_sample_data_init(&sample, bp->attr.bp_addr, 0); |
f5ffe02e | 9015 | |
a4eaf7f1 | 9016 | if (!bp->hw.state && !perf_exclude_event(bp, regs)) |
a8b0ca17 | 9017 | perf_swevent_event(bp, 1, &sample, regs); |
24f1e32c FW |
9018 | } |
9019 | #endif | |
9020 | ||
375637bc AS |
9021 | /* |
9022 | * Allocate a new address filter | |
9023 | */ | |
9024 | static struct perf_addr_filter * | |
9025 | perf_addr_filter_new(struct perf_event *event, struct list_head *filters) | |
9026 | { | |
9027 | int node = cpu_to_node(event->cpu == -1 ? 0 : event->cpu); | |
9028 | struct perf_addr_filter *filter; | |
9029 | ||
9030 | filter = kzalloc_node(sizeof(*filter), GFP_KERNEL, node); | |
9031 | if (!filter) | |
9032 | return NULL; | |
9033 | ||
9034 | INIT_LIST_HEAD(&filter->entry); | |
9035 | list_add_tail(&filter->entry, filters); | |
9036 | ||
9037 | return filter; | |
9038 | } | |
9039 | ||
9040 | static void free_filters_list(struct list_head *filters) | |
9041 | { | |
9042 | struct perf_addr_filter *filter, *iter; | |
9043 | ||
9044 | list_for_each_entry_safe(filter, iter, filters, entry) { | |
9511bce9 | 9045 | path_put(&filter->path); |
375637bc AS |
9046 | list_del(&filter->entry); |
9047 | kfree(filter); | |
9048 | } | |
9049 | } | |
9050 | ||
9051 | /* | |
9052 | * Free existing address filters and optionally install new ones | |
9053 | */ | |
9054 | static void perf_addr_filters_splice(struct perf_event *event, | |
9055 | struct list_head *head) | |
9056 | { | |
9057 | unsigned long flags; | |
9058 | LIST_HEAD(list); | |
9059 | ||
9060 | if (!has_addr_filter(event)) | |
9061 | return; | |
9062 | ||
9063 | /* don't bother with children, they don't have their own filters */ | |
9064 | if (event->parent) | |
9065 | return; | |
9066 | ||
9067 | raw_spin_lock_irqsave(&event->addr_filters.lock, flags); | |
9068 | ||
9069 | list_splice_init(&event->addr_filters.list, &list); | |
9070 | if (head) | |
9071 | list_splice(head, &event->addr_filters.list); | |
9072 | ||
9073 | raw_spin_unlock_irqrestore(&event->addr_filters.lock, flags); | |
9074 | ||
9075 | free_filters_list(&list); | |
9076 | } | |
9077 | ||
9078 | /* | |
9079 | * Scan through mm's vmas and see if one of them matches the | |
9080 | * @filter; if so, adjust filter's address range. | |
9081 | * Called with mm::mmap_sem down for reading. | |
9082 | */ | |
c60f83b8 AS |
9083 | static void perf_addr_filter_apply(struct perf_addr_filter *filter, |
9084 | struct mm_struct *mm, | |
9085 | struct perf_addr_filter_range *fr) | |
375637bc AS |
9086 | { |
9087 | struct vm_area_struct *vma; | |
9088 | ||
9089 | for (vma = mm->mmap; vma; vma = vma->vm_next) { | |
c60f83b8 | 9090 | if (!vma->vm_file) |
375637bc AS |
9091 | continue; |
9092 | ||
c60f83b8 AS |
9093 | if (perf_addr_filter_vma_adjust(filter, vma, fr)) |
9094 | return; | |
375637bc | 9095 | } |
375637bc AS |
9096 | } |
9097 | ||
9098 | /* | |
9099 | * Update event's address range filters based on the | |
9100 | * task's existing mappings, if any. | |
9101 | */ | |
9102 | static void perf_event_addr_filters_apply(struct perf_event *event) | |
9103 | { | |
9104 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
9105 | struct task_struct *task = READ_ONCE(event->ctx->task); | |
9106 | struct perf_addr_filter *filter; | |
9107 | struct mm_struct *mm = NULL; | |
9108 | unsigned int count = 0; | |
9109 | unsigned long flags; | |
9110 | ||
9111 | /* | |
9112 | * We may observe TASK_TOMBSTONE, which means that the event tear-down | |
9113 | * will stop on the parent's child_mutex that our caller is also holding | |
9114 | */ | |
9115 | if (task == TASK_TOMBSTONE) | |
9116 | return; | |
9117 | ||
52a44f83 AS |
9118 | if (ifh->nr_file_filters) { |
9119 | mm = get_task_mm(event->ctx->task); | |
9120 | if (!mm) | |
9121 | goto restart; | |
375637bc | 9122 | |
52a44f83 AS |
9123 | down_read(&mm->mmap_sem); |
9124 | } | |
375637bc AS |
9125 | |
9126 | raw_spin_lock_irqsave(&ifh->lock, flags); | |
9127 | list_for_each_entry(filter, &ifh->list, entry) { | |
52a44f83 AS |
9128 | if (filter->path.dentry) { |
9129 | /* | |
9130 | * Adjust base offset if the filter is associated to a | |
9131 | * binary that needs to be mapped: | |
9132 | */ | |
9133 | event->addr_filter_ranges[count].start = 0; | |
9134 | event->addr_filter_ranges[count].size = 0; | |
375637bc | 9135 | |
c60f83b8 | 9136 | perf_addr_filter_apply(filter, mm, &event->addr_filter_ranges[count]); |
52a44f83 AS |
9137 | } else { |
9138 | event->addr_filter_ranges[count].start = filter->offset; | |
9139 | event->addr_filter_ranges[count].size = filter->size; | |
9140 | } | |
375637bc AS |
9141 | |
9142 | count++; | |
9143 | } | |
9144 | ||
9145 | event->addr_filters_gen++; | |
9146 | raw_spin_unlock_irqrestore(&ifh->lock, flags); | |
9147 | ||
52a44f83 AS |
9148 | if (ifh->nr_file_filters) { |
9149 | up_read(&mm->mmap_sem); | |
375637bc | 9150 | |
52a44f83 AS |
9151 | mmput(mm); |
9152 | } | |
375637bc AS |
9153 | |
9154 | restart: | |
767ae086 | 9155 | perf_event_stop(event, 1); |
375637bc AS |
9156 | } |
9157 | ||
9158 | /* | |
9159 | * Address range filtering: limiting the data to certain | |
9160 | * instruction address ranges. Filters are ioctl()ed to us from | |
9161 | * userspace as ascii strings. | |
9162 | * | |
9163 | * Filter string format: | |
9164 | * | |
9165 | * ACTION RANGE_SPEC | |
9166 | * where ACTION is one of the | |
9167 | * * "filter": limit the trace to this region | |
9168 | * * "start": start tracing from this address | |
9169 | * * "stop": stop tracing at this address/region; | |
9170 | * RANGE_SPEC is | |
9171 | * * for kernel addresses: <start address>[/<size>] | |
9172 | * * for object files: <start address>[/<size>]@</path/to/object/file> | |
9173 | * | |
6ed70cf3 AS |
9174 | * if <size> is not specified or is zero, the range is treated as a single |
9175 | * address; not valid for ACTION=="filter". | |
375637bc AS |
9176 | */ |
9177 | enum { | |
e96271f3 | 9178 | IF_ACT_NONE = -1, |
375637bc AS |
9179 | IF_ACT_FILTER, |
9180 | IF_ACT_START, | |
9181 | IF_ACT_STOP, | |
9182 | IF_SRC_FILE, | |
9183 | IF_SRC_KERNEL, | |
9184 | IF_SRC_FILEADDR, | |
9185 | IF_SRC_KERNELADDR, | |
9186 | }; | |
9187 | ||
9188 | enum { | |
9189 | IF_STATE_ACTION = 0, | |
9190 | IF_STATE_SOURCE, | |
9191 | IF_STATE_END, | |
9192 | }; | |
9193 | ||
9194 | static const match_table_t if_tokens = { | |
9195 | { IF_ACT_FILTER, "filter" }, | |
9196 | { IF_ACT_START, "start" }, | |
9197 | { IF_ACT_STOP, "stop" }, | |
9198 | { IF_SRC_FILE, "%u/%u@%s" }, | |
9199 | { IF_SRC_KERNEL, "%u/%u" }, | |
9200 | { IF_SRC_FILEADDR, "%u@%s" }, | |
9201 | { IF_SRC_KERNELADDR, "%u" }, | |
e96271f3 | 9202 | { IF_ACT_NONE, NULL }, |
375637bc AS |
9203 | }; |
9204 | ||
9205 | /* | |
9206 | * Address filter string parser | |
9207 | */ | |
9208 | static int | |
9209 | perf_event_parse_addr_filter(struct perf_event *event, char *fstr, | |
9210 | struct list_head *filters) | |
9211 | { | |
9212 | struct perf_addr_filter *filter = NULL; | |
9213 | char *start, *orig, *filename = NULL; | |
375637bc AS |
9214 | substring_t args[MAX_OPT_ARGS]; |
9215 | int state = IF_STATE_ACTION, token; | |
9216 | unsigned int kernel = 0; | |
9217 | int ret = -EINVAL; | |
9218 | ||
9219 | orig = fstr = kstrdup(fstr, GFP_KERNEL); | |
9220 | if (!fstr) | |
9221 | return -ENOMEM; | |
9222 | ||
9223 | while ((start = strsep(&fstr, " ,\n")) != NULL) { | |
6ed70cf3 AS |
9224 | static const enum perf_addr_filter_action_t actions[] = { |
9225 | [IF_ACT_FILTER] = PERF_ADDR_FILTER_ACTION_FILTER, | |
9226 | [IF_ACT_START] = PERF_ADDR_FILTER_ACTION_START, | |
9227 | [IF_ACT_STOP] = PERF_ADDR_FILTER_ACTION_STOP, | |
9228 | }; | |
375637bc AS |
9229 | ret = -EINVAL; |
9230 | ||
9231 | if (!*start) | |
9232 | continue; | |
9233 | ||
9234 | /* filter definition begins */ | |
9235 | if (state == IF_STATE_ACTION) { | |
9236 | filter = perf_addr_filter_new(event, filters); | |
9237 | if (!filter) | |
9238 | goto fail; | |
9239 | } | |
9240 | ||
9241 | token = match_token(start, if_tokens, args); | |
9242 | switch (token) { | |
9243 | case IF_ACT_FILTER: | |
9244 | case IF_ACT_START: | |
375637bc AS |
9245 | case IF_ACT_STOP: |
9246 | if (state != IF_STATE_ACTION) | |
9247 | goto fail; | |
9248 | ||
6ed70cf3 | 9249 | filter->action = actions[token]; |
375637bc AS |
9250 | state = IF_STATE_SOURCE; |
9251 | break; | |
9252 | ||
9253 | case IF_SRC_KERNELADDR: | |
9254 | case IF_SRC_KERNEL: | |
9255 | kernel = 1; | |
10c3405f | 9256 | /* fall through */ |
375637bc AS |
9257 | |
9258 | case IF_SRC_FILEADDR: | |
9259 | case IF_SRC_FILE: | |
9260 | if (state != IF_STATE_SOURCE) | |
9261 | goto fail; | |
9262 | ||
375637bc AS |
9263 | *args[0].to = 0; |
9264 | ret = kstrtoul(args[0].from, 0, &filter->offset); | |
9265 | if (ret) | |
9266 | goto fail; | |
9267 | ||
6ed70cf3 | 9268 | if (token == IF_SRC_KERNEL || token == IF_SRC_FILE) { |
375637bc AS |
9269 | *args[1].to = 0; |
9270 | ret = kstrtoul(args[1].from, 0, &filter->size); | |
9271 | if (ret) | |
9272 | goto fail; | |
9273 | } | |
9274 | ||
4059ffd0 | 9275 | if (token == IF_SRC_FILE || token == IF_SRC_FILEADDR) { |
6ed70cf3 | 9276 | int fpos = token == IF_SRC_FILE ? 2 : 1; |
4059ffd0 MP |
9277 | |
9278 | filename = match_strdup(&args[fpos]); | |
375637bc AS |
9279 | if (!filename) { |
9280 | ret = -ENOMEM; | |
9281 | goto fail; | |
9282 | } | |
9283 | } | |
9284 | ||
9285 | state = IF_STATE_END; | |
9286 | break; | |
9287 | ||
9288 | default: | |
9289 | goto fail; | |
9290 | } | |
9291 | ||
9292 | /* | |
9293 | * Filter definition is fully parsed, validate and install it. | |
9294 | * Make sure that it doesn't contradict itself or the event's | |
9295 | * attribute. | |
9296 | */ | |
9297 | if (state == IF_STATE_END) { | |
9ccbfbb1 | 9298 | ret = -EINVAL; |
375637bc AS |
9299 | if (kernel && event->attr.exclude_kernel) |
9300 | goto fail; | |
9301 | ||
6ed70cf3 AS |
9302 | /* |
9303 | * ACTION "filter" must have a non-zero length region | |
9304 | * specified. | |
9305 | */ | |
9306 | if (filter->action == PERF_ADDR_FILTER_ACTION_FILTER && | |
9307 | !filter->size) | |
9308 | goto fail; | |
9309 | ||
375637bc AS |
9310 | if (!kernel) { |
9311 | if (!filename) | |
9312 | goto fail; | |
9313 | ||
6ce77bfd AS |
9314 | /* |
9315 | * For now, we only support file-based filters | |
9316 | * in per-task events; doing so for CPU-wide | |
9317 | * events requires additional context switching | |
9318 | * trickery, since same object code will be | |
9319 | * mapped at different virtual addresses in | |
9320 | * different processes. | |
9321 | */ | |
9322 | ret = -EOPNOTSUPP; | |
9323 | if (!event->ctx->task) | |
9324 | goto fail_free_name; | |
9325 | ||
375637bc | 9326 | /* look up the path and grab its inode */ |
9511bce9 SL |
9327 | ret = kern_path(filename, LOOKUP_FOLLOW, |
9328 | &filter->path); | |
375637bc AS |
9329 | if (ret) |
9330 | goto fail_free_name; | |
9331 | ||
375637bc AS |
9332 | kfree(filename); |
9333 | filename = NULL; | |
9334 | ||
9335 | ret = -EINVAL; | |
9511bce9 SL |
9336 | if (!filter->path.dentry || |
9337 | !S_ISREG(d_inode(filter->path.dentry) | |
9338 | ->i_mode)) | |
375637bc | 9339 | goto fail; |
6ce77bfd AS |
9340 | |
9341 | event->addr_filters.nr_file_filters++; | |
375637bc AS |
9342 | } |
9343 | ||
9344 | /* ready to consume more filters */ | |
9345 | state = IF_STATE_ACTION; | |
9346 | filter = NULL; | |
9347 | } | |
9348 | } | |
9349 | ||
9350 | if (state != IF_STATE_ACTION) | |
9351 | goto fail; | |
9352 | ||
9353 | kfree(orig); | |
9354 | ||
9355 | return 0; | |
9356 | ||
9357 | fail_free_name: | |
9358 | kfree(filename); | |
9359 | fail: | |
9360 | free_filters_list(filters); | |
9361 | kfree(orig); | |
9362 | ||
9363 | return ret; | |
9364 | } | |
9365 | ||
9366 | static int | |
9367 | perf_event_set_addr_filter(struct perf_event *event, char *filter_str) | |
9368 | { | |
9369 | LIST_HEAD(filters); | |
9370 | int ret; | |
9371 | ||
9372 | /* | |
9373 | * Since this is called in perf_ioctl() path, we're already holding | |
9374 | * ctx::mutex. | |
9375 | */ | |
9376 | lockdep_assert_held(&event->ctx->mutex); | |
9377 | ||
9378 | if (WARN_ON_ONCE(event->parent)) | |
9379 | return -EINVAL; | |
9380 | ||
375637bc AS |
9381 | ret = perf_event_parse_addr_filter(event, filter_str, &filters); |
9382 | if (ret) | |
6ce77bfd | 9383 | goto fail_clear_files; |
375637bc AS |
9384 | |
9385 | ret = event->pmu->addr_filters_validate(&filters); | |
6ce77bfd AS |
9386 | if (ret) |
9387 | goto fail_free_filters; | |
375637bc AS |
9388 | |
9389 | /* remove existing filters, if any */ | |
9390 | perf_addr_filters_splice(event, &filters); | |
9391 | ||
9392 | /* install new filters */ | |
9393 | perf_event_for_each_child(event, perf_event_addr_filters_apply); | |
9394 | ||
6ce77bfd AS |
9395 | return ret; |
9396 | ||
9397 | fail_free_filters: | |
9398 | free_filters_list(&filters); | |
9399 | ||
9400 | fail_clear_files: | |
9401 | event->addr_filters.nr_file_filters = 0; | |
9402 | ||
375637bc AS |
9403 | return ret; |
9404 | } | |
9405 | ||
c796bbbe AS |
9406 | static int perf_event_set_filter(struct perf_event *event, void __user *arg) |
9407 | { | |
c796bbbe | 9408 | int ret = -EINVAL; |
e12f03d7 | 9409 | char *filter_str; |
c796bbbe AS |
9410 | |
9411 | filter_str = strndup_user(arg, PAGE_SIZE); | |
9412 | if (IS_ERR(filter_str)) | |
9413 | return PTR_ERR(filter_str); | |
9414 | ||
e12f03d7 SL |
9415 | #ifdef CONFIG_EVENT_TRACING |
9416 | if (perf_event_is_tracing(event)) { | |
9417 | struct perf_event_context *ctx = event->ctx; | |
9418 | ||
9419 | /* | |
9420 | * Beware, here be dragons!! | |
9421 | * | |
9422 | * the tracepoint muck will deadlock against ctx->mutex, but | |
9423 | * the tracepoint stuff does not actually need it. So | |
9424 | * temporarily drop ctx->mutex. As per perf_event_ctx_lock() we | |
9425 | * already have a reference on ctx. | |
9426 | * | |
9427 | * This can result in event getting moved to a different ctx, | |
9428 | * but that does not affect the tracepoint state. | |
9429 | */ | |
9430 | mutex_unlock(&ctx->mutex); | |
9431 | ret = ftrace_profile_set_filter(event, event->attr.config, filter_str); | |
9432 | mutex_lock(&ctx->mutex); | |
9433 | } else | |
9434 | #endif | |
9435 | if (has_addr_filter(event)) | |
375637bc | 9436 | ret = perf_event_set_addr_filter(event, filter_str); |
c796bbbe AS |
9437 | |
9438 | kfree(filter_str); | |
9439 | return ret; | |
9440 | } | |
9441 | ||
b0a873eb PZ |
9442 | /* |
9443 | * hrtimer based swevent callback | |
9444 | */ | |
f29ac756 | 9445 | |
b0a873eb | 9446 | static enum hrtimer_restart perf_swevent_hrtimer(struct hrtimer *hrtimer) |
f29ac756 | 9447 | { |
b0a873eb PZ |
9448 | enum hrtimer_restart ret = HRTIMER_RESTART; |
9449 | struct perf_sample_data data; | |
9450 | struct pt_regs *regs; | |
9451 | struct perf_event *event; | |
9452 | u64 period; | |
f29ac756 | 9453 | |
b0a873eb | 9454 | event = container_of(hrtimer, struct perf_event, hw.hrtimer); |
ba3dd36c PZ |
9455 | |
9456 | if (event->state != PERF_EVENT_STATE_ACTIVE) | |
9457 | return HRTIMER_NORESTART; | |
9458 | ||
b0a873eb | 9459 | event->pmu->read(event); |
f344011c | 9460 | |
fd0d000b | 9461 | perf_sample_data_init(&data, 0, event->hw.last_period); |
b0a873eb PZ |
9462 | regs = get_irq_regs(); |
9463 | ||
9464 | if (regs && !perf_exclude_event(event, regs)) { | |
77aeeebd | 9465 | if (!(event->attr.exclude_idle && is_idle_task(current))) |
33b07b8b | 9466 | if (__perf_event_overflow(event, 1, &data, regs)) |
b0a873eb PZ |
9467 | ret = HRTIMER_NORESTART; |
9468 | } | |
24f1e32c | 9469 | |
b0a873eb PZ |
9470 | period = max_t(u64, 10000, event->hw.sample_period); |
9471 | hrtimer_forward_now(hrtimer, ns_to_ktime(period)); | |
24f1e32c | 9472 | |
b0a873eb | 9473 | return ret; |
f29ac756 PZ |
9474 | } |
9475 | ||
b0a873eb | 9476 | static void perf_swevent_start_hrtimer(struct perf_event *event) |
5c92d124 | 9477 | { |
b0a873eb | 9478 | struct hw_perf_event *hwc = &event->hw; |
5d508e82 FBH |
9479 | s64 period; |
9480 | ||
9481 | if (!is_sampling_event(event)) | |
9482 | return; | |
f5ffe02e | 9483 | |
5d508e82 FBH |
9484 | period = local64_read(&hwc->period_left); |
9485 | if (period) { | |
9486 | if (period < 0) | |
9487 | period = 10000; | |
fa407f35 | 9488 | |
5d508e82 FBH |
9489 | local64_set(&hwc->period_left, 0); |
9490 | } else { | |
9491 | period = max_t(u64, 10000, hwc->sample_period); | |
9492 | } | |
3497d206 TG |
9493 | hrtimer_start(&hwc->hrtimer, ns_to_ktime(period), |
9494 | HRTIMER_MODE_REL_PINNED); | |
24f1e32c | 9495 | } |
b0a873eb PZ |
9496 | |
9497 | static void perf_swevent_cancel_hrtimer(struct perf_event *event) | |
24f1e32c | 9498 | { |
b0a873eb PZ |
9499 | struct hw_perf_event *hwc = &event->hw; |
9500 | ||
6c7e550f | 9501 | if (is_sampling_event(event)) { |
b0a873eb | 9502 | ktime_t remaining = hrtimer_get_remaining(&hwc->hrtimer); |
fa407f35 | 9503 | local64_set(&hwc->period_left, ktime_to_ns(remaining)); |
b0a873eb PZ |
9504 | |
9505 | hrtimer_cancel(&hwc->hrtimer); | |
9506 | } | |
24f1e32c FW |
9507 | } |
9508 | ||
ba3dd36c PZ |
9509 | static void perf_swevent_init_hrtimer(struct perf_event *event) |
9510 | { | |
9511 | struct hw_perf_event *hwc = &event->hw; | |
9512 | ||
9513 | if (!is_sampling_event(event)) | |
9514 | return; | |
9515 | ||
9516 | hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); | |
9517 | hwc->hrtimer.function = perf_swevent_hrtimer; | |
9518 | ||
9519 | /* | |
9520 | * Since hrtimers have a fixed rate, we can do a static freq->period | |
9521 | * mapping and avoid the whole period adjust feedback stuff. | |
9522 | */ | |
9523 | if (event->attr.freq) { | |
9524 | long freq = event->attr.sample_freq; | |
9525 | ||
9526 | event->attr.sample_period = NSEC_PER_SEC / freq; | |
9527 | hwc->sample_period = event->attr.sample_period; | |
9528 | local64_set(&hwc->period_left, hwc->sample_period); | |
778141e3 | 9529 | hwc->last_period = hwc->sample_period; |
ba3dd36c PZ |
9530 | event->attr.freq = 0; |
9531 | } | |
9532 | } | |
9533 | ||
b0a873eb PZ |
9534 | /* |
9535 | * Software event: cpu wall time clock | |
9536 | */ | |
9537 | ||
9538 | static void cpu_clock_event_update(struct perf_event *event) | |
24f1e32c | 9539 | { |
b0a873eb PZ |
9540 | s64 prev; |
9541 | u64 now; | |
9542 | ||
a4eaf7f1 | 9543 | now = local_clock(); |
b0a873eb PZ |
9544 | prev = local64_xchg(&event->hw.prev_count, now); |
9545 | local64_add(now - prev, &event->count); | |
24f1e32c | 9546 | } |
24f1e32c | 9547 | |
a4eaf7f1 | 9548 | static void cpu_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 9549 | { |
a4eaf7f1 | 9550 | local64_set(&event->hw.prev_count, local_clock()); |
b0a873eb | 9551 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
9552 | } |
9553 | ||
a4eaf7f1 | 9554 | static void cpu_clock_event_stop(struct perf_event *event, int flags) |
f29ac756 | 9555 | { |
b0a873eb PZ |
9556 | perf_swevent_cancel_hrtimer(event); |
9557 | cpu_clock_event_update(event); | |
9558 | } | |
f29ac756 | 9559 | |
a4eaf7f1 PZ |
9560 | static int cpu_clock_event_add(struct perf_event *event, int flags) |
9561 | { | |
9562 | if (flags & PERF_EF_START) | |
9563 | cpu_clock_event_start(event, flags); | |
6a694a60 | 9564 | perf_event_update_userpage(event); |
a4eaf7f1 PZ |
9565 | |
9566 | return 0; | |
9567 | } | |
9568 | ||
9569 | static void cpu_clock_event_del(struct perf_event *event, int flags) | |
9570 | { | |
9571 | cpu_clock_event_stop(event, flags); | |
9572 | } | |
9573 | ||
b0a873eb PZ |
9574 | static void cpu_clock_event_read(struct perf_event *event) |
9575 | { | |
9576 | cpu_clock_event_update(event); | |
9577 | } | |
f344011c | 9578 | |
b0a873eb PZ |
9579 | static int cpu_clock_event_init(struct perf_event *event) |
9580 | { | |
9581 | if (event->attr.type != PERF_TYPE_SOFTWARE) | |
9582 | return -ENOENT; | |
9583 | ||
9584 | if (event->attr.config != PERF_COUNT_SW_CPU_CLOCK) | |
9585 | return -ENOENT; | |
9586 | ||
2481c5fa SE |
9587 | /* |
9588 | * no branch sampling for software events | |
9589 | */ | |
9590 | if (has_branch_stack(event)) | |
9591 | return -EOPNOTSUPP; | |
9592 | ||
ba3dd36c PZ |
9593 | perf_swevent_init_hrtimer(event); |
9594 | ||
b0a873eb | 9595 | return 0; |
f29ac756 PZ |
9596 | } |
9597 | ||
b0a873eb | 9598 | static struct pmu perf_cpu_clock = { |
89a1e187 PZ |
9599 | .task_ctx_nr = perf_sw_context, |
9600 | ||
34f43927 PZ |
9601 | .capabilities = PERF_PMU_CAP_NO_NMI, |
9602 | ||
b0a873eb | 9603 | .event_init = cpu_clock_event_init, |
a4eaf7f1 PZ |
9604 | .add = cpu_clock_event_add, |
9605 | .del = cpu_clock_event_del, | |
9606 | .start = cpu_clock_event_start, | |
9607 | .stop = cpu_clock_event_stop, | |
b0a873eb PZ |
9608 | .read = cpu_clock_event_read, |
9609 | }; | |
9610 | ||
9611 | /* | |
9612 | * Software event: task time clock | |
9613 | */ | |
9614 | ||
9615 | static void task_clock_event_update(struct perf_event *event, u64 now) | |
5c92d124 | 9616 | { |
b0a873eb PZ |
9617 | u64 prev; |
9618 | s64 delta; | |
5c92d124 | 9619 | |
b0a873eb PZ |
9620 | prev = local64_xchg(&event->hw.prev_count, now); |
9621 | delta = now - prev; | |
9622 | local64_add(delta, &event->count); | |
9623 | } | |
5c92d124 | 9624 | |
a4eaf7f1 | 9625 | static void task_clock_event_start(struct perf_event *event, int flags) |
b0a873eb | 9626 | { |
a4eaf7f1 | 9627 | local64_set(&event->hw.prev_count, event->ctx->time); |
b0a873eb | 9628 | perf_swevent_start_hrtimer(event); |
b0a873eb PZ |
9629 | } |
9630 | ||
a4eaf7f1 | 9631 | static void task_clock_event_stop(struct perf_event *event, int flags) |
b0a873eb PZ |
9632 | { |
9633 | perf_swevent_cancel_hrtimer(event); | |
9634 | task_clock_event_update(event, event->ctx->time); | |
a4eaf7f1 PZ |
9635 | } |
9636 | ||
9637 | static int task_clock_event_add(struct perf_event *event, int flags) | |
9638 | { | |
9639 | if (flags & PERF_EF_START) | |
9640 | task_clock_event_start(event, flags); | |
6a694a60 | 9641 | perf_event_update_userpage(event); |
b0a873eb | 9642 | |
a4eaf7f1 PZ |
9643 | return 0; |
9644 | } | |
9645 | ||
9646 | static void task_clock_event_del(struct perf_event *event, int flags) | |
9647 | { | |
9648 | task_clock_event_stop(event, PERF_EF_UPDATE); | |
b0a873eb PZ |
9649 | } |
9650 | ||
9651 | static void task_clock_event_read(struct perf_event *event) | |
9652 | { | |
768a06e2 PZ |
9653 | u64 now = perf_clock(); |
9654 | u64 delta = now - event->ctx->timestamp; | |
9655 | u64 time = event->ctx->time + delta; | |
b0a873eb PZ |
9656 | |
9657 | task_clock_event_update(event, time); | |
9658 | } | |
9659 | ||
9660 | static int task_clock_event_init(struct perf_event *event) | |
6fb2915d | 9661 | { |
b0a873eb PZ |
9662 | if (event->attr.type != PERF_TYPE_SOFTWARE) |
9663 | return -ENOENT; | |
9664 | ||
9665 | if (event->attr.config != PERF_COUNT_SW_TASK_CLOCK) | |
9666 | return -ENOENT; | |
9667 | ||
2481c5fa SE |
9668 | /* |
9669 | * no branch sampling for software events | |
9670 | */ | |
9671 | if (has_branch_stack(event)) | |
9672 | return -EOPNOTSUPP; | |
9673 | ||
ba3dd36c PZ |
9674 | perf_swevent_init_hrtimer(event); |
9675 | ||
b0a873eb | 9676 | return 0; |
6fb2915d LZ |
9677 | } |
9678 | ||
b0a873eb | 9679 | static struct pmu perf_task_clock = { |
89a1e187 PZ |
9680 | .task_ctx_nr = perf_sw_context, |
9681 | ||
34f43927 PZ |
9682 | .capabilities = PERF_PMU_CAP_NO_NMI, |
9683 | ||
b0a873eb | 9684 | .event_init = task_clock_event_init, |
a4eaf7f1 PZ |
9685 | .add = task_clock_event_add, |
9686 | .del = task_clock_event_del, | |
9687 | .start = task_clock_event_start, | |
9688 | .stop = task_clock_event_stop, | |
b0a873eb PZ |
9689 | .read = task_clock_event_read, |
9690 | }; | |
6fb2915d | 9691 | |
ad5133b7 | 9692 | static void perf_pmu_nop_void(struct pmu *pmu) |
e077df4f | 9693 | { |
e077df4f | 9694 | } |
6fb2915d | 9695 | |
fbbe0701 SB |
9696 | static void perf_pmu_nop_txn(struct pmu *pmu, unsigned int flags) |
9697 | { | |
9698 | } | |
9699 | ||
ad5133b7 | 9700 | static int perf_pmu_nop_int(struct pmu *pmu) |
6fb2915d | 9701 | { |
ad5133b7 | 9702 | return 0; |
6fb2915d LZ |
9703 | } |
9704 | ||
81ec3f3c JO |
9705 | static int perf_event_nop_int(struct perf_event *event, u64 value) |
9706 | { | |
9707 | return 0; | |
9708 | } | |
9709 | ||
18ab2cd3 | 9710 | static DEFINE_PER_CPU(unsigned int, nop_txn_flags); |
fbbe0701 SB |
9711 | |
9712 | static void perf_pmu_start_txn(struct pmu *pmu, unsigned int flags) | |
6fb2915d | 9713 | { |
fbbe0701 SB |
9714 | __this_cpu_write(nop_txn_flags, flags); |
9715 | ||
9716 | if (flags & ~PERF_PMU_TXN_ADD) | |
9717 | return; | |
9718 | ||
ad5133b7 | 9719 | perf_pmu_disable(pmu); |
6fb2915d LZ |
9720 | } |
9721 | ||
ad5133b7 PZ |
9722 | static int perf_pmu_commit_txn(struct pmu *pmu) |
9723 | { | |
fbbe0701 SB |
9724 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
9725 | ||
9726 | __this_cpu_write(nop_txn_flags, 0); | |
9727 | ||
9728 | if (flags & ~PERF_PMU_TXN_ADD) | |
9729 | return 0; | |
9730 | ||
ad5133b7 PZ |
9731 | perf_pmu_enable(pmu); |
9732 | return 0; | |
9733 | } | |
e077df4f | 9734 | |
ad5133b7 | 9735 | static void perf_pmu_cancel_txn(struct pmu *pmu) |
24f1e32c | 9736 | { |
fbbe0701 SB |
9737 | unsigned int flags = __this_cpu_read(nop_txn_flags); |
9738 | ||
9739 | __this_cpu_write(nop_txn_flags, 0); | |
9740 | ||
9741 | if (flags & ~PERF_PMU_TXN_ADD) | |
9742 | return; | |
9743 | ||
ad5133b7 | 9744 | perf_pmu_enable(pmu); |
24f1e32c FW |
9745 | } |
9746 | ||
35edc2a5 PZ |
9747 | static int perf_event_idx_default(struct perf_event *event) |
9748 | { | |
c719f560 | 9749 | return 0; |
35edc2a5 PZ |
9750 | } |
9751 | ||
8dc85d54 PZ |
9752 | /* |
9753 | * Ensures all contexts with the same task_ctx_nr have the same | |
9754 | * pmu_cpu_context too. | |
9755 | */ | |
9e317041 | 9756 | static struct perf_cpu_context __percpu *find_pmu_context(int ctxn) |
24f1e32c | 9757 | { |
8dc85d54 | 9758 | struct pmu *pmu; |
b326e956 | 9759 | |
8dc85d54 PZ |
9760 | if (ctxn < 0) |
9761 | return NULL; | |
24f1e32c | 9762 | |
8dc85d54 PZ |
9763 | list_for_each_entry(pmu, &pmus, entry) { |
9764 | if (pmu->task_ctx_nr == ctxn) | |
9765 | return pmu->pmu_cpu_context; | |
9766 | } | |
24f1e32c | 9767 | |
8dc85d54 | 9768 | return NULL; |
24f1e32c FW |
9769 | } |
9770 | ||
51676957 PZ |
9771 | static void free_pmu_context(struct pmu *pmu) |
9772 | { | |
df0062b2 WD |
9773 | /* |
9774 | * Static contexts such as perf_sw_context have a global lifetime | |
9775 | * and may be shared between different PMUs. Avoid freeing them | |
9776 | * when a single PMU is going away. | |
9777 | */ | |
9778 | if (pmu->task_ctx_nr > perf_invalid_context) | |
9779 | return; | |
9780 | ||
51676957 | 9781 | free_percpu(pmu->pmu_cpu_context); |
24f1e32c | 9782 | } |
6e855cd4 AS |
9783 | |
9784 | /* | |
9785 | * Let userspace know that this PMU supports address range filtering: | |
9786 | */ | |
9787 | static ssize_t nr_addr_filters_show(struct device *dev, | |
9788 | struct device_attribute *attr, | |
9789 | char *page) | |
9790 | { | |
9791 | struct pmu *pmu = dev_get_drvdata(dev); | |
9792 | ||
9793 | return snprintf(page, PAGE_SIZE - 1, "%d\n", pmu->nr_addr_filters); | |
9794 | } | |
9795 | DEVICE_ATTR_RO(nr_addr_filters); | |
9796 | ||
2e80a82a | 9797 | static struct idr pmu_idr; |
d6d020e9 | 9798 | |
abe43400 PZ |
9799 | static ssize_t |
9800 | type_show(struct device *dev, struct device_attribute *attr, char *page) | |
9801 | { | |
9802 | struct pmu *pmu = dev_get_drvdata(dev); | |
9803 | ||
9804 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->type); | |
9805 | } | |
90826ca7 | 9806 | static DEVICE_ATTR_RO(type); |
abe43400 | 9807 | |
62b85639 SE |
9808 | static ssize_t |
9809 | perf_event_mux_interval_ms_show(struct device *dev, | |
9810 | struct device_attribute *attr, | |
9811 | char *page) | |
9812 | { | |
9813 | struct pmu *pmu = dev_get_drvdata(dev); | |
9814 | ||
9815 | return snprintf(page, PAGE_SIZE-1, "%d\n", pmu->hrtimer_interval_ms); | |
9816 | } | |
9817 | ||
272325c4 PZ |
9818 | static DEFINE_MUTEX(mux_interval_mutex); |
9819 | ||
62b85639 SE |
9820 | static ssize_t |
9821 | perf_event_mux_interval_ms_store(struct device *dev, | |
9822 | struct device_attribute *attr, | |
9823 | const char *buf, size_t count) | |
9824 | { | |
9825 | struct pmu *pmu = dev_get_drvdata(dev); | |
9826 | int timer, cpu, ret; | |
9827 | ||
9828 | ret = kstrtoint(buf, 0, &timer); | |
9829 | if (ret) | |
9830 | return ret; | |
9831 | ||
9832 | if (timer < 1) | |
9833 | return -EINVAL; | |
9834 | ||
9835 | /* same value, noting to do */ | |
9836 | if (timer == pmu->hrtimer_interval_ms) | |
9837 | return count; | |
9838 | ||
272325c4 | 9839 | mutex_lock(&mux_interval_mutex); |
62b85639 SE |
9840 | pmu->hrtimer_interval_ms = timer; |
9841 | ||
9842 | /* update all cpuctx for this PMU */ | |
a63fbed7 | 9843 | cpus_read_lock(); |
272325c4 | 9844 | for_each_online_cpu(cpu) { |
62b85639 SE |
9845 | struct perf_cpu_context *cpuctx; |
9846 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
9847 | cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * timer); | |
9848 | ||
272325c4 PZ |
9849 | cpu_function_call(cpu, |
9850 | (remote_function_f)perf_mux_hrtimer_restart, cpuctx); | |
62b85639 | 9851 | } |
a63fbed7 | 9852 | cpus_read_unlock(); |
272325c4 | 9853 | mutex_unlock(&mux_interval_mutex); |
62b85639 SE |
9854 | |
9855 | return count; | |
9856 | } | |
90826ca7 | 9857 | static DEVICE_ATTR_RW(perf_event_mux_interval_ms); |
62b85639 | 9858 | |
90826ca7 GKH |
9859 | static struct attribute *pmu_dev_attrs[] = { |
9860 | &dev_attr_type.attr, | |
9861 | &dev_attr_perf_event_mux_interval_ms.attr, | |
9862 | NULL, | |
abe43400 | 9863 | }; |
90826ca7 | 9864 | ATTRIBUTE_GROUPS(pmu_dev); |
abe43400 PZ |
9865 | |
9866 | static int pmu_bus_running; | |
9867 | static struct bus_type pmu_bus = { | |
9868 | .name = "event_source", | |
90826ca7 | 9869 | .dev_groups = pmu_dev_groups, |
abe43400 PZ |
9870 | }; |
9871 | ||
9872 | static void pmu_dev_release(struct device *dev) | |
9873 | { | |
9874 | kfree(dev); | |
9875 | } | |
9876 | ||
9877 | static int pmu_dev_alloc(struct pmu *pmu) | |
9878 | { | |
9879 | int ret = -ENOMEM; | |
9880 | ||
9881 | pmu->dev = kzalloc(sizeof(struct device), GFP_KERNEL); | |
9882 | if (!pmu->dev) | |
9883 | goto out; | |
9884 | ||
0c9d42ed | 9885 | pmu->dev->groups = pmu->attr_groups; |
abe43400 PZ |
9886 | device_initialize(pmu->dev); |
9887 | ret = dev_set_name(pmu->dev, "%s", pmu->name); | |
9888 | if (ret) | |
9889 | goto free_dev; | |
9890 | ||
9891 | dev_set_drvdata(pmu->dev, pmu); | |
9892 | pmu->dev->bus = &pmu_bus; | |
9893 | pmu->dev->release = pmu_dev_release; | |
9894 | ret = device_add(pmu->dev); | |
9895 | if (ret) | |
9896 | goto free_dev; | |
9897 | ||
6e855cd4 AS |
9898 | /* For PMUs with address filters, throw in an extra attribute: */ |
9899 | if (pmu->nr_addr_filters) | |
9900 | ret = device_create_file(pmu->dev, &dev_attr_nr_addr_filters); | |
9901 | ||
9902 | if (ret) | |
9903 | goto del_dev; | |
9904 | ||
f3a3a825 JO |
9905 | if (pmu->attr_update) |
9906 | ret = sysfs_update_groups(&pmu->dev->kobj, pmu->attr_update); | |
9907 | ||
9908 | if (ret) | |
9909 | goto del_dev; | |
9910 | ||
abe43400 PZ |
9911 | out: |
9912 | return ret; | |
9913 | ||
6e855cd4 AS |
9914 | del_dev: |
9915 | device_del(pmu->dev); | |
9916 | ||
abe43400 PZ |
9917 | free_dev: |
9918 | put_device(pmu->dev); | |
9919 | goto out; | |
9920 | } | |
9921 | ||
547e9fd7 | 9922 | static struct lock_class_key cpuctx_mutex; |
facc4307 | 9923 | static struct lock_class_key cpuctx_lock; |
547e9fd7 | 9924 | |
03d8e80b | 9925 | int perf_pmu_register(struct pmu *pmu, const char *name, int type) |
24f1e32c | 9926 | { |
108b02cf | 9927 | int cpu, ret; |
24f1e32c | 9928 | |
b0a873eb | 9929 | mutex_lock(&pmus_lock); |
33696fc0 PZ |
9930 | ret = -ENOMEM; |
9931 | pmu->pmu_disable_count = alloc_percpu(int); | |
9932 | if (!pmu->pmu_disable_count) | |
9933 | goto unlock; | |
f29ac756 | 9934 | |
2e80a82a PZ |
9935 | pmu->type = -1; |
9936 | if (!name) | |
9937 | goto skip_type; | |
9938 | pmu->name = name; | |
9939 | ||
9940 | if (type < 0) { | |
0e9c3be2 TH |
9941 | type = idr_alloc(&pmu_idr, pmu, PERF_TYPE_MAX, 0, GFP_KERNEL); |
9942 | if (type < 0) { | |
9943 | ret = type; | |
2e80a82a PZ |
9944 | goto free_pdc; |
9945 | } | |
9946 | } | |
9947 | pmu->type = type; | |
9948 | ||
abe43400 PZ |
9949 | if (pmu_bus_running) { |
9950 | ret = pmu_dev_alloc(pmu); | |
9951 | if (ret) | |
9952 | goto free_idr; | |
9953 | } | |
9954 | ||
2e80a82a | 9955 | skip_type: |
26657848 PZ |
9956 | if (pmu->task_ctx_nr == perf_hw_context) { |
9957 | static int hw_context_taken = 0; | |
9958 | ||
5101ef20 MR |
9959 | /* |
9960 | * Other than systems with heterogeneous CPUs, it never makes | |
9961 | * sense for two PMUs to share perf_hw_context. PMUs which are | |
9962 | * uncore must use perf_invalid_context. | |
9963 | */ | |
9964 | if (WARN_ON_ONCE(hw_context_taken && | |
9965 | !(pmu->capabilities & PERF_PMU_CAP_HETEROGENEOUS_CPUS))) | |
26657848 PZ |
9966 | pmu->task_ctx_nr = perf_invalid_context; |
9967 | ||
9968 | hw_context_taken = 1; | |
9969 | } | |
9970 | ||
8dc85d54 PZ |
9971 | pmu->pmu_cpu_context = find_pmu_context(pmu->task_ctx_nr); |
9972 | if (pmu->pmu_cpu_context) | |
9973 | goto got_cpu_context; | |
f29ac756 | 9974 | |
c4814202 | 9975 | ret = -ENOMEM; |
108b02cf PZ |
9976 | pmu->pmu_cpu_context = alloc_percpu(struct perf_cpu_context); |
9977 | if (!pmu->pmu_cpu_context) | |
abe43400 | 9978 | goto free_dev; |
f344011c | 9979 | |
108b02cf PZ |
9980 | for_each_possible_cpu(cpu) { |
9981 | struct perf_cpu_context *cpuctx; | |
9982 | ||
9983 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
eb184479 | 9984 | __perf_event_init_context(&cpuctx->ctx); |
547e9fd7 | 9985 | lockdep_set_class(&cpuctx->ctx.mutex, &cpuctx_mutex); |
facc4307 | 9986 | lockdep_set_class(&cpuctx->ctx.lock, &cpuctx_lock); |
108b02cf | 9987 | cpuctx->ctx.pmu = pmu; |
a63fbed7 | 9988 | cpuctx->online = cpumask_test_cpu(cpu, perf_online_mask); |
9e630205 | 9989 | |
272325c4 | 9990 | __perf_mux_hrtimer_init(cpuctx, cpu); |
108b02cf | 9991 | } |
76e1d904 | 9992 | |
8dc85d54 | 9993 | got_cpu_context: |
ad5133b7 PZ |
9994 | if (!pmu->start_txn) { |
9995 | if (pmu->pmu_enable) { | |
9996 | /* | |
9997 | * If we have pmu_enable/pmu_disable calls, install | |
9998 | * transaction stubs that use that to try and batch | |
9999 | * hardware accesses. | |
10000 | */ | |
10001 | pmu->start_txn = perf_pmu_start_txn; | |
10002 | pmu->commit_txn = perf_pmu_commit_txn; | |
10003 | pmu->cancel_txn = perf_pmu_cancel_txn; | |
10004 | } else { | |
fbbe0701 | 10005 | pmu->start_txn = perf_pmu_nop_txn; |
ad5133b7 PZ |
10006 | pmu->commit_txn = perf_pmu_nop_int; |
10007 | pmu->cancel_txn = perf_pmu_nop_void; | |
f344011c | 10008 | } |
5c92d124 | 10009 | } |
15dbf27c | 10010 | |
ad5133b7 PZ |
10011 | if (!pmu->pmu_enable) { |
10012 | pmu->pmu_enable = perf_pmu_nop_void; | |
10013 | pmu->pmu_disable = perf_pmu_nop_void; | |
10014 | } | |
10015 | ||
81ec3f3c JO |
10016 | if (!pmu->check_period) |
10017 | pmu->check_period = perf_event_nop_int; | |
10018 | ||
35edc2a5 PZ |
10019 | if (!pmu->event_idx) |
10020 | pmu->event_idx = perf_event_idx_default; | |
10021 | ||
b0a873eb | 10022 | list_add_rcu(&pmu->entry, &pmus); |
bed5b25a | 10023 | atomic_set(&pmu->exclusive_cnt, 0); |
33696fc0 PZ |
10024 | ret = 0; |
10025 | unlock: | |
b0a873eb PZ |
10026 | mutex_unlock(&pmus_lock); |
10027 | ||
33696fc0 | 10028 | return ret; |
108b02cf | 10029 | |
abe43400 PZ |
10030 | free_dev: |
10031 | device_del(pmu->dev); | |
10032 | put_device(pmu->dev); | |
10033 | ||
2e80a82a PZ |
10034 | free_idr: |
10035 | if (pmu->type >= PERF_TYPE_MAX) | |
10036 | idr_remove(&pmu_idr, pmu->type); | |
10037 | ||
108b02cf PZ |
10038 | free_pdc: |
10039 | free_percpu(pmu->pmu_disable_count); | |
10040 | goto unlock; | |
f29ac756 | 10041 | } |
c464c76e | 10042 | EXPORT_SYMBOL_GPL(perf_pmu_register); |
f29ac756 | 10043 | |
b0a873eb | 10044 | void perf_pmu_unregister(struct pmu *pmu) |
5c92d124 | 10045 | { |
b0a873eb PZ |
10046 | mutex_lock(&pmus_lock); |
10047 | list_del_rcu(&pmu->entry); | |
5c92d124 | 10048 | |
0475f9ea | 10049 | /* |
cde8e884 PZ |
10050 | * We dereference the pmu list under both SRCU and regular RCU, so |
10051 | * synchronize against both of those. | |
0475f9ea | 10052 | */ |
b0a873eb | 10053 | synchronize_srcu(&pmus_srcu); |
cde8e884 | 10054 | synchronize_rcu(); |
d6d020e9 | 10055 | |
33696fc0 | 10056 | free_percpu(pmu->pmu_disable_count); |
2e80a82a PZ |
10057 | if (pmu->type >= PERF_TYPE_MAX) |
10058 | idr_remove(&pmu_idr, pmu->type); | |
a9f97721 | 10059 | if (pmu_bus_running) { |
0933840a JO |
10060 | if (pmu->nr_addr_filters) |
10061 | device_remove_file(pmu->dev, &dev_attr_nr_addr_filters); | |
10062 | device_del(pmu->dev); | |
10063 | put_device(pmu->dev); | |
10064 | } | |
51676957 | 10065 | free_pmu_context(pmu); |
a9f97721 | 10066 | mutex_unlock(&pmus_lock); |
b0a873eb | 10067 | } |
c464c76e | 10068 | EXPORT_SYMBOL_GPL(perf_pmu_unregister); |
d6d020e9 | 10069 | |
e321d02d KL |
10070 | static inline bool has_extended_regs(struct perf_event *event) |
10071 | { | |
10072 | return (event->attr.sample_regs_user & PERF_REG_EXTENDED_MASK) || | |
10073 | (event->attr.sample_regs_intr & PERF_REG_EXTENDED_MASK); | |
10074 | } | |
10075 | ||
cc34b98b MR |
10076 | static int perf_try_init_event(struct pmu *pmu, struct perf_event *event) |
10077 | { | |
ccd41c86 | 10078 | struct perf_event_context *ctx = NULL; |
cc34b98b MR |
10079 | int ret; |
10080 | ||
10081 | if (!try_module_get(pmu->module)) | |
10082 | return -ENODEV; | |
ccd41c86 | 10083 | |
0c7296ca PZ |
10084 | /* |
10085 | * A number of pmu->event_init() methods iterate the sibling_list to, | |
10086 | * for example, validate if the group fits on the PMU. Therefore, | |
10087 | * if this is a sibling event, acquire the ctx->mutex to protect | |
10088 | * the sibling_list. | |
10089 | */ | |
10090 | if (event->group_leader != event && pmu->task_ctx_nr != perf_sw_context) { | |
8b10c5e2 PZ |
10091 | /* |
10092 | * This ctx->mutex can nest when we're called through | |
10093 | * inheritance. See the perf_event_ctx_lock_nested() comment. | |
10094 | */ | |
10095 | ctx = perf_event_ctx_lock_nested(event->group_leader, | |
10096 | SINGLE_DEPTH_NESTING); | |
ccd41c86 PZ |
10097 | BUG_ON(!ctx); |
10098 | } | |
10099 | ||
cc34b98b MR |
10100 | event->pmu = pmu; |
10101 | ret = pmu->event_init(event); | |
ccd41c86 PZ |
10102 | |
10103 | if (ctx) | |
10104 | perf_event_ctx_unlock(event->group_leader, ctx); | |
10105 | ||
cc6795ae | 10106 | if (!ret) { |
e321d02d KL |
10107 | if (!(pmu->capabilities & PERF_PMU_CAP_EXTENDED_REGS) && |
10108 | has_extended_regs(event)) | |
10109 | ret = -EOPNOTSUPP; | |
10110 | ||
cc6795ae | 10111 | if (pmu->capabilities & PERF_PMU_CAP_NO_EXCLUDE && |
e321d02d | 10112 | event_has_any_exclude_flag(event)) |
cc6795ae | 10113 | ret = -EINVAL; |
e321d02d KL |
10114 | |
10115 | if (ret && event->destroy) | |
10116 | event->destroy(event); | |
cc6795ae AM |
10117 | } |
10118 | ||
cc34b98b MR |
10119 | if (ret) |
10120 | module_put(pmu->module); | |
10121 | ||
10122 | return ret; | |
10123 | } | |
10124 | ||
18ab2cd3 | 10125 | static struct pmu *perf_init_event(struct perf_event *event) |
b0a873eb | 10126 | { |
85c617ab | 10127 | struct pmu *pmu; |
b0a873eb | 10128 | int idx; |
940c5b29 | 10129 | int ret; |
b0a873eb PZ |
10130 | |
10131 | idx = srcu_read_lock(&pmus_srcu); | |
2e80a82a | 10132 | |
40999312 KL |
10133 | /* Try parent's PMU first: */ |
10134 | if (event->parent && event->parent->pmu) { | |
10135 | pmu = event->parent->pmu; | |
10136 | ret = perf_try_init_event(pmu, event); | |
10137 | if (!ret) | |
10138 | goto unlock; | |
10139 | } | |
10140 | ||
2e80a82a PZ |
10141 | rcu_read_lock(); |
10142 | pmu = idr_find(&pmu_idr, event->attr.type); | |
10143 | rcu_read_unlock(); | |
940c5b29 | 10144 | if (pmu) { |
cc34b98b | 10145 | ret = perf_try_init_event(pmu, event); |
940c5b29 LM |
10146 | if (ret) |
10147 | pmu = ERR_PTR(ret); | |
2e80a82a | 10148 | goto unlock; |
940c5b29 | 10149 | } |
2e80a82a | 10150 | |
b0a873eb | 10151 | list_for_each_entry_rcu(pmu, &pmus, entry) { |
cc34b98b | 10152 | ret = perf_try_init_event(pmu, event); |
b0a873eb | 10153 | if (!ret) |
e5f4d339 | 10154 | goto unlock; |
76e1d904 | 10155 | |
b0a873eb PZ |
10156 | if (ret != -ENOENT) { |
10157 | pmu = ERR_PTR(ret); | |
e5f4d339 | 10158 | goto unlock; |
f344011c | 10159 | } |
5c92d124 | 10160 | } |
e5f4d339 PZ |
10161 | pmu = ERR_PTR(-ENOENT); |
10162 | unlock: | |
b0a873eb | 10163 | srcu_read_unlock(&pmus_srcu, idx); |
15dbf27c | 10164 | |
4aeb0b42 | 10165 | return pmu; |
5c92d124 IM |
10166 | } |
10167 | ||
f2fb6bef KL |
10168 | static void attach_sb_event(struct perf_event *event) |
10169 | { | |
10170 | struct pmu_event_list *pel = per_cpu_ptr(&pmu_sb_events, event->cpu); | |
10171 | ||
10172 | raw_spin_lock(&pel->lock); | |
10173 | list_add_rcu(&event->sb_list, &pel->list); | |
10174 | raw_spin_unlock(&pel->lock); | |
10175 | } | |
10176 | ||
aab5b71e PZ |
10177 | /* |
10178 | * We keep a list of all !task (and therefore per-cpu) events | |
10179 | * that need to receive side-band records. | |
10180 | * | |
10181 | * This avoids having to scan all the various PMU per-cpu contexts | |
10182 | * looking for them. | |
10183 | */ | |
f2fb6bef KL |
10184 | static void account_pmu_sb_event(struct perf_event *event) |
10185 | { | |
a4f144eb | 10186 | if (is_sb_event(event)) |
f2fb6bef KL |
10187 | attach_sb_event(event); |
10188 | } | |
10189 | ||
4beb31f3 FW |
10190 | static void account_event_cpu(struct perf_event *event, int cpu) |
10191 | { | |
10192 | if (event->parent) | |
10193 | return; | |
10194 | ||
4beb31f3 FW |
10195 | if (is_cgroup_event(event)) |
10196 | atomic_inc(&per_cpu(perf_cgroup_events, cpu)); | |
10197 | } | |
10198 | ||
555e0c1e FW |
10199 | /* Freq events need the tick to stay alive (see perf_event_task_tick). */ |
10200 | static void account_freq_event_nohz(void) | |
10201 | { | |
10202 | #ifdef CONFIG_NO_HZ_FULL | |
10203 | /* Lock so we don't race with concurrent unaccount */ | |
10204 | spin_lock(&nr_freq_lock); | |
10205 | if (atomic_inc_return(&nr_freq_events) == 1) | |
10206 | tick_nohz_dep_set(TICK_DEP_BIT_PERF_EVENTS); | |
10207 | spin_unlock(&nr_freq_lock); | |
10208 | #endif | |
10209 | } | |
10210 | ||
10211 | static void account_freq_event(void) | |
10212 | { | |
10213 | if (tick_nohz_full_enabled()) | |
10214 | account_freq_event_nohz(); | |
10215 | else | |
10216 | atomic_inc(&nr_freq_events); | |
10217 | } | |
10218 | ||
10219 | ||
766d6c07 FW |
10220 | static void account_event(struct perf_event *event) |
10221 | { | |
25432ae9 PZ |
10222 | bool inc = false; |
10223 | ||
4beb31f3 FW |
10224 | if (event->parent) |
10225 | return; | |
10226 | ||
766d6c07 | 10227 | if (event->attach_state & PERF_ATTACH_TASK) |
25432ae9 | 10228 | inc = true; |
766d6c07 FW |
10229 | if (event->attr.mmap || event->attr.mmap_data) |
10230 | atomic_inc(&nr_mmap_events); | |
10231 | if (event->attr.comm) | |
10232 | atomic_inc(&nr_comm_events); | |
e4222673 HB |
10233 | if (event->attr.namespaces) |
10234 | atomic_inc(&nr_namespaces_events); | |
766d6c07 FW |
10235 | if (event->attr.task) |
10236 | atomic_inc(&nr_task_events); | |
555e0c1e FW |
10237 | if (event->attr.freq) |
10238 | account_freq_event(); | |
45ac1403 AH |
10239 | if (event->attr.context_switch) { |
10240 | atomic_inc(&nr_switch_events); | |
25432ae9 | 10241 | inc = true; |
45ac1403 | 10242 | } |
4beb31f3 | 10243 | if (has_branch_stack(event)) |
25432ae9 | 10244 | inc = true; |
4beb31f3 | 10245 | if (is_cgroup_event(event)) |
25432ae9 | 10246 | inc = true; |
76193a94 SL |
10247 | if (event->attr.ksymbol) |
10248 | atomic_inc(&nr_ksymbol_events); | |
6ee52e2a SL |
10249 | if (event->attr.bpf_event) |
10250 | atomic_inc(&nr_bpf_events); | |
25432ae9 | 10251 | |
9107c89e | 10252 | if (inc) { |
5bce9db1 AS |
10253 | /* |
10254 | * We need the mutex here because static_branch_enable() | |
10255 | * must complete *before* the perf_sched_count increment | |
10256 | * becomes visible. | |
10257 | */ | |
9107c89e PZ |
10258 | if (atomic_inc_not_zero(&perf_sched_count)) |
10259 | goto enabled; | |
10260 | ||
10261 | mutex_lock(&perf_sched_mutex); | |
10262 | if (!atomic_read(&perf_sched_count)) { | |
10263 | static_branch_enable(&perf_sched_events); | |
10264 | /* | |
10265 | * Guarantee that all CPUs observe they key change and | |
10266 | * call the perf scheduling hooks before proceeding to | |
10267 | * install events that need them. | |
10268 | */ | |
0809d954 | 10269 | synchronize_rcu(); |
9107c89e PZ |
10270 | } |
10271 | /* | |
10272 | * Now that we have waited for the sync_sched(), allow further | |
10273 | * increments to by-pass the mutex. | |
10274 | */ | |
10275 | atomic_inc(&perf_sched_count); | |
10276 | mutex_unlock(&perf_sched_mutex); | |
10277 | } | |
10278 | enabled: | |
4beb31f3 FW |
10279 | |
10280 | account_event_cpu(event, event->cpu); | |
f2fb6bef KL |
10281 | |
10282 | account_pmu_sb_event(event); | |
766d6c07 FW |
10283 | } |
10284 | ||
0793a61d | 10285 | /* |
788faab7 | 10286 | * Allocate and initialize an event structure |
0793a61d | 10287 | */ |
cdd6c482 | 10288 | static struct perf_event * |
c3f00c70 | 10289 | perf_event_alloc(struct perf_event_attr *attr, int cpu, |
d580ff86 PZ |
10290 | struct task_struct *task, |
10291 | struct perf_event *group_leader, | |
10292 | struct perf_event *parent_event, | |
4dc0da86 | 10293 | perf_overflow_handler_t overflow_handler, |
79dff51e | 10294 | void *context, int cgroup_fd) |
0793a61d | 10295 | { |
51b0fe39 | 10296 | struct pmu *pmu; |
cdd6c482 IM |
10297 | struct perf_event *event; |
10298 | struct hw_perf_event *hwc; | |
90983b16 | 10299 | long err = -EINVAL; |
0793a61d | 10300 | |
66832eb4 ON |
10301 | if ((unsigned)cpu >= nr_cpu_ids) { |
10302 | if (!task || cpu != -1) | |
10303 | return ERR_PTR(-EINVAL); | |
10304 | } | |
10305 | ||
c3f00c70 | 10306 | event = kzalloc(sizeof(*event), GFP_KERNEL); |
cdd6c482 | 10307 | if (!event) |
d5d2bc0d | 10308 | return ERR_PTR(-ENOMEM); |
0793a61d | 10309 | |
04289bb9 | 10310 | /* |
cdd6c482 | 10311 | * Single events are their own group leaders, with an |
04289bb9 IM |
10312 | * empty sibling list: |
10313 | */ | |
10314 | if (!group_leader) | |
cdd6c482 | 10315 | group_leader = event; |
04289bb9 | 10316 | |
cdd6c482 IM |
10317 | mutex_init(&event->child_mutex); |
10318 | INIT_LIST_HEAD(&event->child_list); | |
fccc714b | 10319 | |
cdd6c482 IM |
10320 | INIT_LIST_HEAD(&event->event_entry); |
10321 | INIT_LIST_HEAD(&event->sibling_list); | |
6668128a | 10322 | INIT_LIST_HEAD(&event->active_list); |
8e1a2031 | 10323 | init_event_group(event); |
10c6db11 | 10324 | INIT_LIST_HEAD(&event->rb_entry); |
71ad88ef | 10325 | INIT_LIST_HEAD(&event->active_entry); |
375637bc | 10326 | INIT_LIST_HEAD(&event->addr_filters.list); |
f3ae75de SE |
10327 | INIT_HLIST_NODE(&event->hlist_entry); |
10328 | ||
10c6db11 | 10329 | |
cdd6c482 | 10330 | init_waitqueue_head(&event->waitq); |
1d54ad94 | 10331 | event->pending_disable = -1; |
e360adbe | 10332 | init_irq_work(&event->pending, perf_pending_event); |
0793a61d | 10333 | |
cdd6c482 | 10334 | mutex_init(&event->mmap_mutex); |
375637bc | 10335 | raw_spin_lock_init(&event->addr_filters.lock); |
7b732a75 | 10336 | |
a6fa941d | 10337 | atomic_long_set(&event->refcount, 1); |
cdd6c482 IM |
10338 | event->cpu = cpu; |
10339 | event->attr = *attr; | |
10340 | event->group_leader = group_leader; | |
10341 | event->pmu = NULL; | |
cdd6c482 | 10342 | event->oncpu = -1; |
a96bbc16 | 10343 | |
cdd6c482 | 10344 | event->parent = parent_event; |
b84fbc9f | 10345 | |
17cf22c3 | 10346 | event->ns = get_pid_ns(task_active_pid_ns(current)); |
cdd6c482 | 10347 | event->id = atomic64_inc_return(&perf_event_id); |
a96bbc16 | 10348 | |
cdd6c482 | 10349 | event->state = PERF_EVENT_STATE_INACTIVE; |
329d876d | 10350 | |
d580ff86 PZ |
10351 | if (task) { |
10352 | event->attach_state = PERF_ATTACH_TASK; | |
d580ff86 | 10353 | /* |
50f16a8b PZ |
10354 | * XXX pmu::event_init needs to know what task to account to |
10355 | * and we cannot use the ctx information because we need the | |
10356 | * pmu before we get a ctx. | |
d580ff86 | 10357 | */ |
621b6d2e | 10358 | get_task_struct(task); |
50f16a8b | 10359 | event->hw.target = task; |
d580ff86 PZ |
10360 | } |
10361 | ||
34f43927 PZ |
10362 | event->clock = &local_clock; |
10363 | if (parent_event) | |
10364 | event->clock = parent_event->clock; | |
10365 | ||
4dc0da86 | 10366 | if (!overflow_handler && parent_event) { |
b326e956 | 10367 | overflow_handler = parent_event->overflow_handler; |
4dc0da86 | 10368 | context = parent_event->overflow_handler_context; |
f1e4ba5b | 10369 | #if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_EVENT_TRACING) |
aa6a5f3c AS |
10370 | if (overflow_handler == bpf_overflow_handler) { |
10371 | struct bpf_prog *prog = bpf_prog_inc(parent_event->prog); | |
10372 | ||
10373 | if (IS_ERR(prog)) { | |
10374 | err = PTR_ERR(prog); | |
10375 | goto err_ns; | |
10376 | } | |
10377 | event->prog = prog; | |
10378 | event->orig_overflow_handler = | |
10379 | parent_event->orig_overflow_handler; | |
10380 | } | |
10381 | #endif | |
4dc0da86 | 10382 | } |
66832eb4 | 10383 | |
1879445d WN |
10384 | if (overflow_handler) { |
10385 | event->overflow_handler = overflow_handler; | |
10386 | event->overflow_handler_context = context; | |
9ecda41a WN |
10387 | } else if (is_write_backward(event)){ |
10388 | event->overflow_handler = perf_event_output_backward; | |
10389 | event->overflow_handler_context = NULL; | |
1879445d | 10390 | } else { |
9ecda41a | 10391 | event->overflow_handler = perf_event_output_forward; |
1879445d WN |
10392 | event->overflow_handler_context = NULL; |
10393 | } | |
97eaf530 | 10394 | |
0231bb53 | 10395 | perf_event__state_init(event); |
a86ed508 | 10396 | |
4aeb0b42 | 10397 | pmu = NULL; |
b8e83514 | 10398 | |
cdd6c482 | 10399 | hwc = &event->hw; |
bd2b5b12 | 10400 | hwc->sample_period = attr->sample_period; |
0d48696f | 10401 | if (attr->freq && attr->sample_freq) |
bd2b5b12 | 10402 | hwc->sample_period = 1; |
eced1dfc | 10403 | hwc->last_period = hwc->sample_period; |
bd2b5b12 | 10404 | |
e7850595 | 10405 | local64_set(&hwc->period_left, hwc->sample_period); |
60db5e09 | 10406 | |
2023b359 | 10407 | /* |
ba5213ae PZ |
10408 | * We currently do not support PERF_SAMPLE_READ on inherited events. |
10409 | * See perf_output_read(). | |
2023b359 | 10410 | */ |
ba5213ae | 10411 | if (attr->inherit && (attr->sample_type & PERF_SAMPLE_READ)) |
90983b16 | 10412 | goto err_ns; |
a46a2300 YZ |
10413 | |
10414 | if (!has_branch_stack(event)) | |
10415 | event->attr.branch_sample_type = 0; | |
2023b359 | 10416 | |
79dff51e MF |
10417 | if (cgroup_fd != -1) { |
10418 | err = perf_cgroup_connect(cgroup_fd, event, attr, group_leader); | |
10419 | if (err) | |
10420 | goto err_ns; | |
10421 | } | |
10422 | ||
b0a873eb | 10423 | pmu = perf_init_event(event); |
85c617ab | 10424 | if (IS_ERR(pmu)) { |
4aeb0b42 | 10425 | err = PTR_ERR(pmu); |
90983b16 | 10426 | goto err_ns; |
621a01ea | 10427 | } |
d5d2bc0d | 10428 | |
bed5b25a AS |
10429 | err = exclusive_event_init(event); |
10430 | if (err) | |
10431 | goto err_pmu; | |
10432 | ||
375637bc | 10433 | if (has_addr_filter(event)) { |
c60f83b8 AS |
10434 | event->addr_filter_ranges = kcalloc(pmu->nr_addr_filters, |
10435 | sizeof(struct perf_addr_filter_range), | |
10436 | GFP_KERNEL); | |
10437 | if (!event->addr_filter_ranges) { | |
36cc2b92 | 10438 | err = -ENOMEM; |
375637bc | 10439 | goto err_per_task; |
36cc2b92 | 10440 | } |
375637bc | 10441 | |
18736eef AS |
10442 | /* |
10443 | * Clone the parent's vma offsets: they are valid until exec() | |
10444 | * even if the mm is not shared with the parent. | |
10445 | */ | |
10446 | if (event->parent) { | |
10447 | struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); | |
10448 | ||
10449 | raw_spin_lock_irq(&ifh->lock); | |
c60f83b8 AS |
10450 | memcpy(event->addr_filter_ranges, |
10451 | event->parent->addr_filter_ranges, | |
10452 | pmu->nr_addr_filters * sizeof(struct perf_addr_filter_range)); | |
18736eef AS |
10453 | raw_spin_unlock_irq(&ifh->lock); |
10454 | } | |
10455 | ||
375637bc AS |
10456 | /* force hw sync on the address filters */ |
10457 | event->addr_filters_gen = 1; | |
10458 | } | |
10459 | ||
cdd6c482 | 10460 | if (!event->parent) { |
927c7a9e | 10461 | if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN) { |
97c79a38 | 10462 | err = get_callchain_buffers(attr->sample_max_stack); |
90983b16 | 10463 | if (err) |
375637bc | 10464 | goto err_addr_filters; |
d010b332 | 10465 | } |
f344011c | 10466 | } |
9ee318a7 | 10467 | |
927a5570 AS |
10468 | /* symmetric to unaccount_event() in _free_event() */ |
10469 | account_event(event); | |
10470 | ||
cdd6c482 | 10471 | return event; |
90983b16 | 10472 | |
375637bc | 10473 | err_addr_filters: |
c60f83b8 | 10474 | kfree(event->addr_filter_ranges); |
375637bc | 10475 | |
bed5b25a AS |
10476 | err_per_task: |
10477 | exclusive_event_destroy(event); | |
10478 | ||
90983b16 FW |
10479 | err_pmu: |
10480 | if (event->destroy) | |
10481 | event->destroy(event); | |
c464c76e | 10482 | module_put(pmu->module); |
90983b16 | 10483 | err_ns: |
79dff51e MF |
10484 | if (is_cgroup_event(event)) |
10485 | perf_detach_cgroup(event); | |
90983b16 FW |
10486 | if (event->ns) |
10487 | put_pid_ns(event->ns); | |
621b6d2e PB |
10488 | if (event->hw.target) |
10489 | put_task_struct(event->hw.target); | |
90983b16 FW |
10490 | kfree(event); |
10491 | ||
10492 | return ERR_PTR(err); | |
0793a61d TG |
10493 | } |
10494 | ||
cdd6c482 IM |
10495 | static int perf_copy_attr(struct perf_event_attr __user *uattr, |
10496 | struct perf_event_attr *attr) | |
974802ea | 10497 | { |
974802ea | 10498 | u32 size; |
cdf8073d | 10499 | int ret; |
974802ea | 10500 | |
96d4f267 | 10501 | if (!access_ok(uattr, PERF_ATTR_SIZE_VER0)) |
974802ea PZ |
10502 | return -EFAULT; |
10503 | ||
10504 | /* | |
10505 | * zero the full structure, so that a short copy will be nice. | |
10506 | */ | |
10507 | memset(attr, 0, sizeof(*attr)); | |
10508 | ||
10509 | ret = get_user(size, &uattr->size); | |
10510 | if (ret) | |
10511 | return ret; | |
10512 | ||
10513 | if (size > PAGE_SIZE) /* silly large */ | |
10514 | goto err_size; | |
10515 | ||
10516 | if (!size) /* abi compat */ | |
10517 | size = PERF_ATTR_SIZE_VER0; | |
10518 | ||
10519 | if (size < PERF_ATTR_SIZE_VER0) | |
10520 | goto err_size; | |
10521 | ||
10522 | /* | |
10523 | * If we're handed a bigger struct than we know of, | |
cdf8073d IS |
10524 | * ensure all the unknown bits are 0 - i.e. new |
10525 | * user-space does not rely on any kernel feature | |
10526 | * extensions we dont know about yet. | |
974802ea PZ |
10527 | */ |
10528 | if (size > sizeof(*attr)) { | |
cdf8073d IS |
10529 | unsigned char __user *addr; |
10530 | unsigned char __user *end; | |
10531 | unsigned char val; | |
974802ea | 10532 | |
cdf8073d IS |
10533 | addr = (void __user *)uattr + sizeof(*attr); |
10534 | end = (void __user *)uattr + size; | |
974802ea | 10535 | |
cdf8073d | 10536 | for (; addr < end; addr++) { |
974802ea PZ |
10537 | ret = get_user(val, addr); |
10538 | if (ret) | |
10539 | return ret; | |
10540 | if (val) | |
10541 | goto err_size; | |
10542 | } | |
b3e62e35 | 10543 | size = sizeof(*attr); |
974802ea PZ |
10544 | } |
10545 | ||
10546 | ret = copy_from_user(attr, uattr, size); | |
10547 | if (ret) | |
10548 | return -EFAULT; | |
10549 | ||
f12f42ac MX |
10550 | attr->size = size; |
10551 | ||
cd757645 | 10552 | if (attr->__reserved_1) |
974802ea PZ |
10553 | return -EINVAL; |
10554 | ||
10555 | if (attr->sample_type & ~(PERF_SAMPLE_MAX-1)) | |
10556 | return -EINVAL; | |
10557 | ||
10558 | if (attr->read_format & ~(PERF_FORMAT_MAX-1)) | |
10559 | return -EINVAL; | |
10560 | ||
bce38cd5 SE |
10561 | if (attr->sample_type & PERF_SAMPLE_BRANCH_STACK) { |
10562 | u64 mask = attr->branch_sample_type; | |
10563 | ||
10564 | /* only using defined bits */ | |
10565 | if (mask & ~(PERF_SAMPLE_BRANCH_MAX-1)) | |
10566 | return -EINVAL; | |
10567 | ||
10568 | /* at least one branch bit must be set */ | |
10569 | if (!(mask & ~PERF_SAMPLE_BRANCH_PLM_ALL)) | |
10570 | return -EINVAL; | |
10571 | ||
bce38cd5 SE |
10572 | /* propagate priv level, when not set for branch */ |
10573 | if (!(mask & PERF_SAMPLE_BRANCH_PLM_ALL)) { | |
10574 | ||
10575 | /* exclude_kernel checked on syscall entry */ | |
10576 | if (!attr->exclude_kernel) | |
10577 | mask |= PERF_SAMPLE_BRANCH_KERNEL; | |
10578 | ||
10579 | if (!attr->exclude_user) | |
10580 | mask |= PERF_SAMPLE_BRANCH_USER; | |
10581 | ||
10582 | if (!attr->exclude_hv) | |
10583 | mask |= PERF_SAMPLE_BRANCH_HV; | |
10584 | /* | |
10585 | * adjust user setting (for HW filter setup) | |
10586 | */ | |
10587 | attr->branch_sample_type = mask; | |
10588 | } | |
e712209a SE |
10589 | /* privileged levels capture (kernel, hv): check permissions */ |
10590 | if ((mask & PERF_SAMPLE_BRANCH_PERM_PLM) | |
2b923c8f SE |
10591 | && perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) |
10592 | return -EACCES; | |
bce38cd5 | 10593 | } |
4018994f | 10594 | |
c5ebcedb | 10595 | if (attr->sample_type & PERF_SAMPLE_REGS_USER) { |
4018994f | 10596 | ret = perf_reg_validate(attr->sample_regs_user); |
c5ebcedb JO |
10597 | if (ret) |
10598 | return ret; | |
10599 | } | |
10600 | ||
10601 | if (attr->sample_type & PERF_SAMPLE_STACK_USER) { | |
10602 | if (!arch_perf_have_user_stack_dump()) | |
10603 | return -ENOSYS; | |
10604 | ||
10605 | /* | |
10606 | * We have __u32 type for the size, but so far | |
10607 | * we can only use __u16 as maximum due to the | |
10608 | * __u16 sample size limit. | |
10609 | */ | |
10610 | if (attr->sample_stack_user >= USHRT_MAX) | |
78b562fb | 10611 | return -EINVAL; |
c5ebcedb | 10612 | else if (!IS_ALIGNED(attr->sample_stack_user, sizeof(u64))) |
78b562fb | 10613 | return -EINVAL; |
c5ebcedb | 10614 | } |
4018994f | 10615 | |
5f970521 JO |
10616 | if (!attr->sample_max_stack) |
10617 | attr->sample_max_stack = sysctl_perf_event_max_stack; | |
10618 | ||
60e2364e SE |
10619 | if (attr->sample_type & PERF_SAMPLE_REGS_INTR) |
10620 | ret = perf_reg_validate(attr->sample_regs_intr); | |
974802ea PZ |
10621 | out: |
10622 | return ret; | |
10623 | ||
10624 | err_size: | |
10625 | put_user(sizeof(*attr), &uattr->size); | |
10626 | ret = -E2BIG; | |
10627 | goto out; | |
10628 | } | |
10629 | ||
ac9721f3 PZ |
10630 | static int |
10631 | perf_event_set_output(struct perf_event *event, struct perf_event *output_event) | |
a4be7c27 | 10632 | { |
b69cf536 | 10633 | struct ring_buffer *rb = NULL; |
a4be7c27 PZ |
10634 | int ret = -EINVAL; |
10635 | ||
ac9721f3 | 10636 | if (!output_event) |
a4be7c27 PZ |
10637 | goto set; |
10638 | ||
ac9721f3 PZ |
10639 | /* don't allow circular references */ |
10640 | if (event == output_event) | |
a4be7c27 PZ |
10641 | goto out; |
10642 | ||
0f139300 PZ |
10643 | /* |
10644 | * Don't allow cross-cpu buffers | |
10645 | */ | |
10646 | if (output_event->cpu != event->cpu) | |
10647 | goto out; | |
10648 | ||
10649 | /* | |
76369139 | 10650 | * If its not a per-cpu rb, it must be the same task. |
0f139300 PZ |
10651 | */ |
10652 | if (output_event->cpu == -1 && output_event->ctx != event->ctx) | |
10653 | goto out; | |
10654 | ||
34f43927 PZ |
10655 | /* |
10656 | * Mixing clocks in the same buffer is trouble you don't need. | |
10657 | */ | |
10658 | if (output_event->clock != event->clock) | |
10659 | goto out; | |
10660 | ||
9ecda41a WN |
10661 | /* |
10662 | * Either writing ring buffer from beginning or from end. | |
10663 | * Mixing is not allowed. | |
10664 | */ | |
10665 | if (is_write_backward(output_event) != is_write_backward(event)) | |
10666 | goto out; | |
10667 | ||
45bfb2e5 PZ |
10668 | /* |
10669 | * If both events generate aux data, they must be on the same PMU | |
10670 | */ | |
10671 | if (has_aux(event) && has_aux(output_event) && | |
10672 | event->pmu != output_event->pmu) | |
10673 | goto out; | |
10674 | ||
a4be7c27 | 10675 | set: |
cdd6c482 | 10676 | mutex_lock(&event->mmap_mutex); |
ac9721f3 PZ |
10677 | /* Can't redirect output if we've got an active mmap() */ |
10678 | if (atomic_read(&event->mmap_count)) | |
10679 | goto unlock; | |
a4be7c27 | 10680 | |
ac9721f3 | 10681 | if (output_event) { |
76369139 FW |
10682 | /* get the rb we want to redirect to */ |
10683 | rb = ring_buffer_get(output_event); | |
10684 | if (!rb) | |
ac9721f3 | 10685 | goto unlock; |
a4be7c27 PZ |
10686 | } |
10687 | ||
b69cf536 | 10688 | ring_buffer_attach(event, rb); |
9bb5d40c | 10689 | |
a4be7c27 | 10690 | ret = 0; |
ac9721f3 PZ |
10691 | unlock: |
10692 | mutex_unlock(&event->mmap_mutex); | |
10693 | ||
a4be7c27 | 10694 | out: |
a4be7c27 PZ |
10695 | return ret; |
10696 | } | |
10697 | ||
f63a8daa PZ |
10698 | static void mutex_lock_double(struct mutex *a, struct mutex *b) |
10699 | { | |
10700 | if (b < a) | |
10701 | swap(a, b); | |
10702 | ||
10703 | mutex_lock(a); | |
10704 | mutex_lock_nested(b, SINGLE_DEPTH_NESTING); | |
10705 | } | |
10706 | ||
34f43927 PZ |
10707 | static int perf_event_set_clock(struct perf_event *event, clockid_t clk_id) |
10708 | { | |
10709 | bool nmi_safe = false; | |
10710 | ||
10711 | switch (clk_id) { | |
10712 | case CLOCK_MONOTONIC: | |
10713 | event->clock = &ktime_get_mono_fast_ns; | |
10714 | nmi_safe = true; | |
10715 | break; | |
10716 | ||
10717 | case CLOCK_MONOTONIC_RAW: | |
10718 | event->clock = &ktime_get_raw_fast_ns; | |
10719 | nmi_safe = true; | |
10720 | break; | |
10721 | ||
10722 | case CLOCK_REALTIME: | |
10723 | event->clock = &ktime_get_real_ns; | |
10724 | break; | |
10725 | ||
10726 | case CLOCK_BOOTTIME: | |
9285ec4c | 10727 | event->clock = &ktime_get_boottime_ns; |
34f43927 PZ |
10728 | break; |
10729 | ||
10730 | case CLOCK_TAI: | |
9285ec4c | 10731 | event->clock = &ktime_get_clocktai_ns; |
34f43927 PZ |
10732 | break; |
10733 | ||
10734 | default: | |
10735 | return -EINVAL; | |
10736 | } | |
10737 | ||
10738 | if (!nmi_safe && !(event->pmu->capabilities & PERF_PMU_CAP_NO_NMI)) | |
10739 | return -EINVAL; | |
10740 | ||
10741 | return 0; | |
10742 | } | |
10743 | ||
321027c1 PZ |
10744 | /* |
10745 | * Variation on perf_event_ctx_lock_nested(), except we take two context | |
10746 | * mutexes. | |
10747 | */ | |
10748 | static struct perf_event_context * | |
10749 | __perf_event_ctx_lock_double(struct perf_event *group_leader, | |
10750 | struct perf_event_context *ctx) | |
10751 | { | |
10752 | struct perf_event_context *gctx; | |
10753 | ||
10754 | again: | |
10755 | rcu_read_lock(); | |
10756 | gctx = READ_ONCE(group_leader->ctx); | |
8c94abbb | 10757 | if (!refcount_inc_not_zero(&gctx->refcount)) { |
321027c1 PZ |
10758 | rcu_read_unlock(); |
10759 | goto again; | |
10760 | } | |
10761 | rcu_read_unlock(); | |
10762 | ||
10763 | mutex_lock_double(&gctx->mutex, &ctx->mutex); | |
10764 | ||
10765 | if (group_leader->ctx != gctx) { | |
10766 | mutex_unlock(&ctx->mutex); | |
10767 | mutex_unlock(&gctx->mutex); | |
10768 | put_ctx(gctx); | |
10769 | goto again; | |
10770 | } | |
10771 | ||
10772 | return gctx; | |
10773 | } | |
10774 | ||
0793a61d | 10775 | /** |
cdd6c482 | 10776 | * sys_perf_event_open - open a performance event, associate it to a task/cpu |
9f66a381 | 10777 | * |
cdd6c482 | 10778 | * @attr_uptr: event_id type attributes for monitoring/sampling |
0793a61d | 10779 | * @pid: target pid |
9f66a381 | 10780 | * @cpu: target cpu |
cdd6c482 | 10781 | * @group_fd: group leader event fd |
0793a61d | 10782 | */ |
cdd6c482 IM |
10783 | SYSCALL_DEFINE5(perf_event_open, |
10784 | struct perf_event_attr __user *, attr_uptr, | |
2743a5b0 | 10785 | pid_t, pid, int, cpu, int, group_fd, unsigned long, flags) |
0793a61d | 10786 | { |
b04243ef PZ |
10787 | struct perf_event *group_leader = NULL, *output_event = NULL; |
10788 | struct perf_event *event, *sibling; | |
cdd6c482 | 10789 | struct perf_event_attr attr; |
f63a8daa | 10790 | struct perf_event_context *ctx, *uninitialized_var(gctx); |
cdd6c482 | 10791 | struct file *event_file = NULL; |
2903ff01 | 10792 | struct fd group = {NULL, 0}; |
38a81da2 | 10793 | struct task_struct *task = NULL; |
89a1e187 | 10794 | struct pmu *pmu; |
ea635c64 | 10795 | int event_fd; |
b04243ef | 10796 | int move_group = 0; |
dc86cabe | 10797 | int err; |
a21b0b35 | 10798 | int f_flags = O_RDWR; |
79dff51e | 10799 | int cgroup_fd = -1; |
0793a61d | 10800 | |
2743a5b0 | 10801 | /* for future expandability... */ |
e5d1367f | 10802 | if (flags & ~PERF_FLAG_ALL) |
2743a5b0 PM |
10803 | return -EINVAL; |
10804 | ||
dc86cabe IM |
10805 | err = perf_copy_attr(attr_uptr, &attr); |
10806 | if (err) | |
10807 | return err; | |
eab656ae | 10808 | |
0764771d PZ |
10809 | if (!attr.exclude_kernel) { |
10810 | if (perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) | |
10811 | return -EACCES; | |
10812 | } | |
10813 | ||
e4222673 HB |
10814 | if (attr.namespaces) { |
10815 | if (!capable(CAP_SYS_ADMIN)) | |
10816 | return -EACCES; | |
10817 | } | |
10818 | ||
df58ab24 | 10819 | if (attr.freq) { |
cdd6c482 | 10820 | if (attr.sample_freq > sysctl_perf_event_sample_rate) |
df58ab24 | 10821 | return -EINVAL; |
0819b2e3 PZ |
10822 | } else { |
10823 | if (attr.sample_period & (1ULL << 63)) | |
10824 | return -EINVAL; | |
df58ab24 PZ |
10825 | } |
10826 | ||
fc7ce9c7 KL |
10827 | /* Only privileged users can get physical addresses */ |
10828 | if ((attr.sample_type & PERF_SAMPLE_PHYS_ADDR) && | |
10829 | perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN)) | |
10830 | return -EACCES; | |
10831 | ||
e5d1367f SE |
10832 | /* |
10833 | * In cgroup mode, the pid argument is used to pass the fd | |
10834 | * opened to the cgroup directory in cgroupfs. The cpu argument | |
10835 | * designates the cpu on which to monitor threads from that | |
10836 | * cgroup. | |
10837 | */ | |
10838 | if ((flags & PERF_FLAG_PID_CGROUP) && (pid == -1 || cpu == -1)) | |
10839 | return -EINVAL; | |
10840 | ||
a21b0b35 YD |
10841 | if (flags & PERF_FLAG_FD_CLOEXEC) |
10842 | f_flags |= O_CLOEXEC; | |
10843 | ||
10844 | event_fd = get_unused_fd_flags(f_flags); | |
ea635c64 AV |
10845 | if (event_fd < 0) |
10846 | return event_fd; | |
10847 | ||
ac9721f3 | 10848 | if (group_fd != -1) { |
2903ff01 AV |
10849 | err = perf_fget_light(group_fd, &group); |
10850 | if (err) | |
d14b12d7 | 10851 | goto err_fd; |
2903ff01 | 10852 | group_leader = group.file->private_data; |
ac9721f3 PZ |
10853 | if (flags & PERF_FLAG_FD_OUTPUT) |
10854 | output_event = group_leader; | |
10855 | if (flags & PERF_FLAG_FD_NO_GROUP) | |
10856 | group_leader = NULL; | |
10857 | } | |
10858 | ||
e5d1367f | 10859 | if (pid != -1 && !(flags & PERF_FLAG_PID_CGROUP)) { |
c6be5a5c PZ |
10860 | task = find_lively_task_by_vpid(pid); |
10861 | if (IS_ERR(task)) { | |
10862 | err = PTR_ERR(task); | |
10863 | goto err_group_fd; | |
10864 | } | |
10865 | } | |
10866 | ||
1f4ee503 PZ |
10867 | if (task && group_leader && |
10868 | group_leader->attr.inherit != attr.inherit) { | |
10869 | err = -EINVAL; | |
10870 | goto err_task; | |
10871 | } | |
10872 | ||
79c9ce57 PZ |
10873 | if (task) { |
10874 | err = mutex_lock_interruptible(&task->signal->cred_guard_mutex); | |
10875 | if (err) | |
e5aeee51 | 10876 | goto err_task; |
79c9ce57 PZ |
10877 | |
10878 | /* | |
10879 | * Reuse ptrace permission checks for now. | |
10880 | * | |
10881 | * We must hold cred_guard_mutex across this and any potential | |
10882 | * perf_install_in_context() call for this new event to | |
10883 | * serialize against exec() altering our credentials (and the | |
10884 | * perf_event_exit_task() that could imply). | |
10885 | */ | |
10886 | err = -EACCES; | |
10887 | if (!ptrace_may_access(task, PTRACE_MODE_READ_REALCREDS)) | |
10888 | goto err_cred; | |
10889 | } | |
10890 | ||
79dff51e MF |
10891 | if (flags & PERF_FLAG_PID_CGROUP) |
10892 | cgroup_fd = pid; | |
10893 | ||
4dc0da86 | 10894 | event = perf_event_alloc(&attr, cpu, task, group_leader, NULL, |
79dff51e | 10895 | NULL, NULL, cgroup_fd); |
d14b12d7 SE |
10896 | if (IS_ERR(event)) { |
10897 | err = PTR_ERR(event); | |
79c9ce57 | 10898 | goto err_cred; |
d14b12d7 SE |
10899 | } |
10900 | ||
53b25335 VW |
10901 | if (is_sampling_event(event)) { |
10902 | if (event->pmu->capabilities & PERF_PMU_CAP_NO_INTERRUPT) { | |
a1396555 | 10903 | err = -EOPNOTSUPP; |
53b25335 VW |
10904 | goto err_alloc; |
10905 | } | |
10906 | } | |
10907 | ||
89a1e187 PZ |
10908 | /* |
10909 | * Special case software events and allow them to be part of | |
10910 | * any hardware group. | |
10911 | */ | |
10912 | pmu = event->pmu; | |
b04243ef | 10913 | |
34f43927 PZ |
10914 | if (attr.use_clockid) { |
10915 | err = perf_event_set_clock(event, attr.clockid); | |
10916 | if (err) | |
10917 | goto err_alloc; | |
10918 | } | |
10919 | ||
4ff6a8de DCC |
10920 | if (pmu->task_ctx_nr == perf_sw_context) |
10921 | event->event_caps |= PERF_EV_CAP_SOFTWARE; | |
10922 | ||
a1150c20 SL |
10923 | if (group_leader) { |
10924 | if (is_software_event(event) && | |
10925 | !in_software_context(group_leader)) { | |
b04243ef | 10926 | /* |
a1150c20 SL |
10927 | * If the event is a sw event, but the group_leader |
10928 | * is on hw context. | |
b04243ef | 10929 | * |
a1150c20 SL |
10930 | * Allow the addition of software events to hw |
10931 | * groups, this is safe because software events | |
10932 | * never fail to schedule. | |
b04243ef | 10933 | */ |
a1150c20 SL |
10934 | pmu = group_leader->ctx->pmu; |
10935 | } else if (!is_software_event(event) && | |
10936 | is_software_event(group_leader) && | |
4ff6a8de | 10937 | (group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { |
b04243ef PZ |
10938 | /* |
10939 | * In case the group is a pure software group, and we | |
10940 | * try to add a hardware event, move the whole group to | |
10941 | * the hardware context. | |
10942 | */ | |
10943 | move_group = 1; | |
10944 | } | |
10945 | } | |
89a1e187 PZ |
10946 | |
10947 | /* | |
10948 | * Get the target context (task or percpu): | |
10949 | */ | |
4af57ef2 | 10950 | ctx = find_get_context(pmu, task, event); |
89a1e187 PZ |
10951 | if (IS_ERR(ctx)) { |
10952 | err = PTR_ERR(ctx); | |
c6be5a5c | 10953 | goto err_alloc; |
89a1e187 PZ |
10954 | } |
10955 | ||
ccff286d | 10956 | /* |
cdd6c482 | 10957 | * Look up the group leader (we will attach this event to it): |
04289bb9 | 10958 | */ |
ac9721f3 | 10959 | if (group_leader) { |
dc86cabe | 10960 | err = -EINVAL; |
04289bb9 | 10961 | |
04289bb9 | 10962 | /* |
ccff286d IM |
10963 | * Do not allow a recursive hierarchy (this new sibling |
10964 | * becoming part of another group-sibling): | |
10965 | */ | |
10966 | if (group_leader->group_leader != group_leader) | |
c3f00c70 | 10967 | goto err_context; |
34f43927 PZ |
10968 | |
10969 | /* All events in a group should have the same clock */ | |
10970 | if (group_leader->clock != event->clock) | |
10971 | goto err_context; | |
10972 | ||
ccff286d | 10973 | /* |
64aee2a9 MR |
10974 | * Make sure we're both events for the same CPU; |
10975 | * grouping events for different CPUs is broken; since | |
10976 | * you can never concurrently schedule them anyhow. | |
04289bb9 | 10977 | */ |
64aee2a9 MR |
10978 | if (group_leader->cpu != event->cpu) |
10979 | goto err_context; | |
c3c87e77 | 10980 | |
64aee2a9 MR |
10981 | /* |
10982 | * Make sure we're both on the same task, or both | |
10983 | * per-CPU events. | |
10984 | */ | |
10985 | if (group_leader->ctx->task != ctx->task) | |
10986 | goto err_context; | |
10987 | ||
10988 | /* | |
10989 | * Do not allow to attach to a group in a different task | |
10990 | * or CPU context. If we're moving SW events, we'll fix | |
10991 | * this up later, so allow that. | |
10992 | */ | |
10993 | if (!move_group && group_leader->ctx != ctx) | |
10994 | goto err_context; | |
b04243ef | 10995 | |
3b6f9e5c PM |
10996 | /* |
10997 | * Only a group leader can be exclusive or pinned | |
10998 | */ | |
0d48696f | 10999 | if (attr.exclusive || attr.pinned) |
c3f00c70 | 11000 | goto err_context; |
ac9721f3 PZ |
11001 | } |
11002 | ||
11003 | if (output_event) { | |
11004 | err = perf_event_set_output(event, output_event); | |
11005 | if (err) | |
c3f00c70 | 11006 | goto err_context; |
ac9721f3 | 11007 | } |
0793a61d | 11008 | |
a21b0b35 YD |
11009 | event_file = anon_inode_getfile("[perf_event]", &perf_fops, event, |
11010 | f_flags); | |
ea635c64 AV |
11011 | if (IS_ERR(event_file)) { |
11012 | err = PTR_ERR(event_file); | |
201c2f85 | 11013 | event_file = NULL; |
c3f00c70 | 11014 | goto err_context; |
ea635c64 | 11015 | } |
9b51f66d | 11016 | |
b04243ef | 11017 | if (move_group) { |
321027c1 PZ |
11018 | gctx = __perf_event_ctx_lock_double(group_leader, ctx); |
11019 | ||
84c4e620 PZ |
11020 | if (gctx->task == TASK_TOMBSTONE) { |
11021 | err = -ESRCH; | |
11022 | goto err_locked; | |
11023 | } | |
321027c1 PZ |
11024 | |
11025 | /* | |
11026 | * Check if we raced against another sys_perf_event_open() call | |
11027 | * moving the software group underneath us. | |
11028 | */ | |
11029 | if (!(group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { | |
11030 | /* | |
11031 | * If someone moved the group out from under us, check | |
11032 | * if this new event wound up on the same ctx, if so | |
11033 | * its the regular !move_group case, otherwise fail. | |
11034 | */ | |
11035 | if (gctx != ctx) { | |
11036 | err = -EINVAL; | |
11037 | goto err_locked; | |
11038 | } else { | |
11039 | perf_event_ctx_unlock(group_leader, gctx); | |
11040 | move_group = 0; | |
11041 | } | |
11042 | } | |
8a58ddae AS |
11043 | |
11044 | /* | |
11045 | * Failure to create exclusive events returns -EBUSY. | |
11046 | */ | |
11047 | err = -EBUSY; | |
11048 | if (!exclusive_event_installable(group_leader, ctx)) | |
11049 | goto err_locked; | |
11050 | ||
11051 | for_each_sibling_event(sibling, group_leader) { | |
11052 | if (!exclusive_event_installable(sibling, ctx)) | |
11053 | goto err_locked; | |
11054 | } | |
f55fc2a5 PZ |
11055 | } else { |
11056 | mutex_lock(&ctx->mutex); | |
11057 | } | |
11058 | ||
84c4e620 PZ |
11059 | if (ctx->task == TASK_TOMBSTONE) { |
11060 | err = -ESRCH; | |
11061 | goto err_locked; | |
11062 | } | |
11063 | ||
a723968c PZ |
11064 | if (!perf_event_validate_size(event)) { |
11065 | err = -E2BIG; | |
11066 | goto err_locked; | |
11067 | } | |
11068 | ||
a63fbed7 TG |
11069 | if (!task) { |
11070 | /* | |
11071 | * Check if the @cpu we're creating an event for is online. | |
11072 | * | |
11073 | * We use the perf_cpu_context::ctx::mutex to serialize against | |
11074 | * the hotplug notifiers. See perf_event_{init,exit}_cpu(). | |
11075 | */ | |
11076 | struct perf_cpu_context *cpuctx = | |
11077 | container_of(ctx, struct perf_cpu_context, ctx); | |
11078 | ||
11079 | if (!cpuctx->online) { | |
11080 | err = -ENODEV; | |
11081 | goto err_locked; | |
11082 | } | |
11083 | } | |
11084 | ||
11085 | ||
f55fc2a5 PZ |
11086 | /* |
11087 | * Must be under the same ctx::mutex as perf_install_in_context(), | |
11088 | * because we need to serialize with concurrent event creation. | |
11089 | */ | |
11090 | if (!exclusive_event_installable(event, ctx)) { | |
f55fc2a5 PZ |
11091 | err = -EBUSY; |
11092 | goto err_locked; | |
11093 | } | |
f63a8daa | 11094 | |
f55fc2a5 PZ |
11095 | WARN_ON_ONCE(ctx->parent_ctx); |
11096 | ||
79c9ce57 PZ |
11097 | /* |
11098 | * This is the point on no return; we cannot fail hereafter. This is | |
11099 | * where we start modifying current state. | |
11100 | */ | |
11101 | ||
f55fc2a5 | 11102 | if (move_group) { |
f63a8daa PZ |
11103 | /* |
11104 | * See perf_event_ctx_lock() for comments on the details | |
11105 | * of swizzling perf_event::ctx. | |
11106 | */ | |
45a0e07a | 11107 | perf_remove_from_context(group_leader, 0); |
279b5165 | 11108 | put_ctx(gctx); |
0231bb53 | 11109 | |
edb39592 | 11110 | for_each_sibling_event(sibling, group_leader) { |
45a0e07a | 11111 | perf_remove_from_context(sibling, 0); |
b04243ef PZ |
11112 | put_ctx(gctx); |
11113 | } | |
b04243ef | 11114 | |
f63a8daa PZ |
11115 | /* |
11116 | * Wait for everybody to stop referencing the events through | |
11117 | * the old lists, before installing it on new lists. | |
11118 | */ | |
0cda4c02 | 11119 | synchronize_rcu(); |
f63a8daa | 11120 | |
8f95b435 PZI |
11121 | /* |
11122 | * Install the group siblings before the group leader. | |
11123 | * | |
11124 | * Because a group leader will try and install the entire group | |
11125 | * (through the sibling list, which is still in-tact), we can | |
11126 | * end up with siblings installed in the wrong context. | |
11127 | * | |
11128 | * By installing siblings first we NO-OP because they're not | |
11129 | * reachable through the group lists. | |
11130 | */ | |
edb39592 | 11131 | for_each_sibling_event(sibling, group_leader) { |
8f95b435 | 11132 | perf_event__state_init(sibling); |
9fc81d87 | 11133 | perf_install_in_context(ctx, sibling, sibling->cpu); |
b04243ef PZ |
11134 | get_ctx(ctx); |
11135 | } | |
8f95b435 PZI |
11136 | |
11137 | /* | |
11138 | * Removing from the context ends up with disabled | |
11139 | * event. What we want here is event in the initial | |
11140 | * startup state, ready to be add into new context. | |
11141 | */ | |
11142 | perf_event__state_init(group_leader); | |
11143 | perf_install_in_context(ctx, group_leader, group_leader->cpu); | |
11144 | get_ctx(ctx); | |
bed5b25a AS |
11145 | } |
11146 | ||
f73e22ab PZ |
11147 | /* |
11148 | * Precalculate sample_data sizes; do while holding ctx::mutex such | |
11149 | * that we're serialized against further additions and before | |
11150 | * perf_install_in_context() which is the point the event is active and | |
11151 | * can use these values. | |
11152 | */ | |
11153 | perf_event__header_size(event); | |
11154 | perf_event__id_header_size(event); | |
11155 | ||
78cd2c74 PZ |
11156 | event->owner = current; |
11157 | ||
e2d37cd2 | 11158 | perf_install_in_context(ctx, event, event->cpu); |
fe4b04fa | 11159 | perf_unpin_context(ctx); |
f63a8daa | 11160 | |
f55fc2a5 | 11161 | if (move_group) |
321027c1 | 11162 | perf_event_ctx_unlock(group_leader, gctx); |
d859e29f | 11163 | mutex_unlock(&ctx->mutex); |
9b51f66d | 11164 | |
79c9ce57 PZ |
11165 | if (task) { |
11166 | mutex_unlock(&task->signal->cred_guard_mutex); | |
11167 | put_task_struct(task); | |
11168 | } | |
11169 | ||
cdd6c482 IM |
11170 | mutex_lock(¤t->perf_event_mutex); |
11171 | list_add_tail(&event->owner_entry, ¤t->perf_event_list); | |
11172 | mutex_unlock(¤t->perf_event_mutex); | |
082ff5a2 | 11173 | |
8a49542c PZ |
11174 | /* |
11175 | * Drop the reference on the group_event after placing the | |
11176 | * new event on the sibling_list. This ensures destruction | |
11177 | * of the group leader will find the pointer to itself in | |
11178 | * perf_group_detach(). | |
11179 | */ | |
2903ff01 | 11180 | fdput(group); |
ea635c64 AV |
11181 | fd_install(event_fd, event_file); |
11182 | return event_fd; | |
0793a61d | 11183 | |
f55fc2a5 PZ |
11184 | err_locked: |
11185 | if (move_group) | |
321027c1 | 11186 | perf_event_ctx_unlock(group_leader, gctx); |
f55fc2a5 PZ |
11187 | mutex_unlock(&ctx->mutex); |
11188 | /* err_file: */ | |
11189 | fput(event_file); | |
c3f00c70 | 11190 | err_context: |
fe4b04fa | 11191 | perf_unpin_context(ctx); |
ea635c64 | 11192 | put_ctx(ctx); |
c6be5a5c | 11193 | err_alloc: |
13005627 PZ |
11194 | /* |
11195 | * If event_file is set, the fput() above will have called ->release() | |
11196 | * and that will take care of freeing the event. | |
11197 | */ | |
11198 | if (!event_file) | |
11199 | free_event(event); | |
79c9ce57 PZ |
11200 | err_cred: |
11201 | if (task) | |
11202 | mutex_unlock(&task->signal->cred_guard_mutex); | |
1f4ee503 | 11203 | err_task: |
e7d0bc04 PZ |
11204 | if (task) |
11205 | put_task_struct(task); | |
89a1e187 | 11206 | err_group_fd: |
2903ff01 | 11207 | fdput(group); |
ea635c64 AV |
11208 | err_fd: |
11209 | put_unused_fd(event_fd); | |
dc86cabe | 11210 | return err; |
0793a61d TG |
11211 | } |
11212 | ||
fb0459d7 AV |
11213 | /** |
11214 | * perf_event_create_kernel_counter | |
11215 | * | |
11216 | * @attr: attributes of the counter to create | |
11217 | * @cpu: cpu in which the counter is bound | |
38a81da2 | 11218 | * @task: task to profile (NULL for percpu) |
fb0459d7 AV |
11219 | */ |
11220 | struct perf_event * | |
11221 | perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu, | |
38a81da2 | 11222 | struct task_struct *task, |
4dc0da86 AK |
11223 | perf_overflow_handler_t overflow_handler, |
11224 | void *context) | |
fb0459d7 | 11225 | { |
fb0459d7 | 11226 | struct perf_event_context *ctx; |
c3f00c70 | 11227 | struct perf_event *event; |
fb0459d7 | 11228 | int err; |
d859e29f | 11229 | |
fb0459d7 AV |
11230 | /* |
11231 | * Get the target context (task or percpu): | |
11232 | */ | |
d859e29f | 11233 | |
4dc0da86 | 11234 | event = perf_event_alloc(attr, cpu, task, NULL, NULL, |
79dff51e | 11235 | overflow_handler, context, -1); |
c3f00c70 PZ |
11236 | if (IS_ERR(event)) { |
11237 | err = PTR_ERR(event); | |
11238 | goto err; | |
11239 | } | |
d859e29f | 11240 | |
f8697762 | 11241 | /* Mark owner so we could distinguish it from user events. */ |
63b6da39 | 11242 | event->owner = TASK_TOMBSTONE; |
f8697762 | 11243 | |
4af57ef2 | 11244 | ctx = find_get_context(event->pmu, task, event); |
c6567f64 FW |
11245 | if (IS_ERR(ctx)) { |
11246 | err = PTR_ERR(ctx); | |
c3f00c70 | 11247 | goto err_free; |
d859e29f | 11248 | } |
fb0459d7 | 11249 | |
fb0459d7 AV |
11250 | WARN_ON_ONCE(ctx->parent_ctx); |
11251 | mutex_lock(&ctx->mutex); | |
84c4e620 PZ |
11252 | if (ctx->task == TASK_TOMBSTONE) { |
11253 | err = -ESRCH; | |
11254 | goto err_unlock; | |
11255 | } | |
11256 | ||
a63fbed7 TG |
11257 | if (!task) { |
11258 | /* | |
11259 | * Check if the @cpu we're creating an event for is online. | |
11260 | * | |
11261 | * We use the perf_cpu_context::ctx::mutex to serialize against | |
11262 | * the hotplug notifiers. See perf_event_{init,exit}_cpu(). | |
11263 | */ | |
11264 | struct perf_cpu_context *cpuctx = | |
11265 | container_of(ctx, struct perf_cpu_context, ctx); | |
11266 | if (!cpuctx->online) { | |
11267 | err = -ENODEV; | |
11268 | goto err_unlock; | |
11269 | } | |
11270 | } | |
11271 | ||
bed5b25a | 11272 | if (!exclusive_event_installable(event, ctx)) { |
bed5b25a | 11273 | err = -EBUSY; |
84c4e620 | 11274 | goto err_unlock; |
bed5b25a AS |
11275 | } |
11276 | ||
fb0459d7 | 11277 | perf_install_in_context(ctx, event, cpu); |
fe4b04fa | 11278 | perf_unpin_context(ctx); |
fb0459d7 AV |
11279 | mutex_unlock(&ctx->mutex); |
11280 | ||
fb0459d7 AV |
11281 | return event; |
11282 | ||
84c4e620 PZ |
11283 | err_unlock: |
11284 | mutex_unlock(&ctx->mutex); | |
11285 | perf_unpin_context(ctx); | |
11286 | put_ctx(ctx); | |
c3f00c70 PZ |
11287 | err_free: |
11288 | free_event(event); | |
11289 | err: | |
c6567f64 | 11290 | return ERR_PTR(err); |
9b51f66d | 11291 | } |
fb0459d7 | 11292 | EXPORT_SYMBOL_GPL(perf_event_create_kernel_counter); |
9b51f66d | 11293 | |
0cda4c02 YZ |
11294 | void perf_pmu_migrate_context(struct pmu *pmu, int src_cpu, int dst_cpu) |
11295 | { | |
11296 | struct perf_event_context *src_ctx; | |
11297 | struct perf_event_context *dst_ctx; | |
11298 | struct perf_event *event, *tmp; | |
11299 | LIST_HEAD(events); | |
11300 | ||
11301 | src_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, src_cpu)->ctx; | |
11302 | dst_ctx = &per_cpu_ptr(pmu->pmu_cpu_context, dst_cpu)->ctx; | |
11303 | ||
f63a8daa PZ |
11304 | /* |
11305 | * See perf_event_ctx_lock() for comments on the details | |
11306 | * of swizzling perf_event::ctx. | |
11307 | */ | |
11308 | mutex_lock_double(&src_ctx->mutex, &dst_ctx->mutex); | |
0cda4c02 YZ |
11309 | list_for_each_entry_safe(event, tmp, &src_ctx->event_list, |
11310 | event_entry) { | |
45a0e07a | 11311 | perf_remove_from_context(event, 0); |
9a545de0 | 11312 | unaccount_event_cpu(event, src_cpu); |
0cda4c02 | 11313 | put_ctx(src_ctx); |
9886167d | 11314 | list_add(&event->migrate_entry, &events); |
0cda4c02 | 11315 | } |
0cda4c02 | 11316 | |
8f95b435 PZI |
11317 | /* |
11318 | * Wait for the events to quiesce before re-instating them. | |
11319 | */ | |
0cda4c02 YZ |
11320 | synchronize_rcu(); |
11321 | ||
8f95b435 PZI |
11322 | /* |
11323 | * Re-instate events in 2 passes. | |
11324 | * | |
11325 | * Skip over group leaders and only install siblings on this first | |
11326 | * pass, siblings will not get enabled without a leader, however a | |
11327 | * leader will enable its siblings, even if those are still on the old | |
11328 | * context. | |
11329 | */ | |
11330 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { | |
11331 | if (event->group_leader == event) | |
11332 | continue; | |
11333 | ||
11334 | list_del(&event->migrate_entry); | |
11335 | if (event->state >= PERF_EVENT_STATE_OFF) | |
11336 | event->state = PERF_EVENT_STATE_INACTIVE; | |
11337 | account_event_cpu(event, dst_cpu); | |
11338 | perf_install_in_context(dst_ctx, event, dst_cpu); | |
11339 | get_ctx(dst_ctx); | |
11340 | } | |
11341 | ||
11342 | /* | |
11343 | * Once all the siblings are setup properly, install the group leaders | |
11344 | * to make it go. | |
11345 | */ | |
9886167d PZ |
11346 | list_for_each_entry_safe(event, tmp, &events, migrate_entry) { |
11347 | list_del(&event->migrate_entry); | |
0cda4c02 YZ |
11348 | if (event->state >= PERF_EVENT_STATE_OFF) |
11349 | event->state = PERF_EVENT_STATE_INACTIVE; | |
9a545de0 | 11350 | account_event_cpu(event, dst_cpu); |
0cda4c02 YZ |
11351 | perf_install_in_context(dst_ctx, event, dst_cpu); |
11352 | get_ctx(dst_ctx); | |
11353 | } | |
11354 | mutex_unlock(&dst_ctx->mutex); | |
f63a8daa | 11355 | mutex_unlock(&src_ctx->mutex); |
0cda4c02 YZ |
11356 | } |
11357 | EXPORT_SYMBOL_GPL(perf_pmu_migrate_context); | |
11358 | ||
cdd6c482 | 11359 | static void sync_child_event(struct perf_event *child_event, |
38b200d6 | 11360 | struct task_struct *child) |
d859e29f | 11361 | { |
cdd6c482 | 11362 | struct perf_event *parent_event = child_event->parent; |
8bc20959 | 11363 | u64 child_val; |
d859e29f | 11364 | |
cdd6c482 IM |
11365 | if (child_event->attr.inherit_stat) |
11366 | perf_event_read_event(child_event, child); | |
38b200d6 | 11367 | |
b5e58793 | 11368 | child_val = perf_event_count(child_event); |
d859e29f PM |
11369 | |
11370 | /* | |
11371 | * Add back the child's count to the parent's count: | |
11372 | */ | |
a6e6dea6 | 11373 | atomic64_add(child_val, &parent_event->child_count); |
cdd6c482 IM |
11374 | atomic64_add(child_event->total_time_enabled, |
11375 | &parent_event->child_total_time_enabled); | |
11376 | atomic64_add(child_event->total_time_running, | |
11377 | &parent_event->child_total_time_running); | |
d859e29f PM |
11378 | } |
11379 | ||
9b51f66d | 11380 | static void |
8ba289b8 PZ |
11381 | perf_event_exit_event(struct perf_event *child_event, |
11382 | struct perf_event_context *child_ctx, | |
11383 | struct task_struct *child) | |
9b51f66d | 11384 | { |
8ba289b8 PZ |
11385 | struct perf_event *parent_event = child_event->parent; |
11386 | ||
1903d50c PZ |
11387 | /* |
11388 | * Do not destroy the 'original' grouping; because of the context | |
11389 | * switch optimization the original events could've ended up in a | |
11390 | * random child task. | |
11391 | * | |
11392 | * If we were to destroy the original group, all group related | |
11393 | * operations would cease to function properly after this random | |
11394 | * child dies. | |
11395 | * | |
11396 | * Do destroy all inherited groups, we don't care about those | |
11397 | * and being thorough is better. | |
11398 | */ | |
32132a3d PZ |
11399 | raw_spin_lock_irq(&child_ctx->lock); |
11400 | WARN_ON_ONCE(child_ctx->is_active); | |
11401 | ||
8ba289b8 | 11402 | if (parent_event) |
32132a3d PZ |
11403 | perf_group_detach(child_event); |
11404 | list_del_event(child_event, child_ctx); | |
0d3d73aa | 11405 | perf_event_set_state(child_event, PERF_EVENT_STATE_EXIT); /* is_event_hup() */ |
32132a3d | 11406 | raw_spin_unlock_irq(&child_ctx->lock); |
0cc0c027 | 11407 | |
9b51f66d | 11408 | /* |
8ba289b8 | 11409 | * Parent events are governed by their filedesc, retain them. |
9b51f66d | 11410 | */ |
8ba289b8 | 11411 | if (!parent_event) { |
179033b3 | 11412 | perf_event_wakeup(child_event); |
8ba289b8 | 11413 | return; |
4bcf349a | 11414 | } |
8ba289b8 PZ |
11415 | /* |
11416 | * Child events can be cleaned up. | |
11417 | */ | |
11418 | ||
11419 | sync_child_event(child_event, child); | |
11420 | ||
11421 | /* | |
11422 | * Remove this event from the parent's list | |
11423 | */ | |
11424 | WARN_ON_ONCE(parent_event->ctx->parent_ctx); | |
11425 | mutex_lock(&parent_event->child_mutex); | |
11426 | list_del_init(&child_event->child_list); | |
11427 | mutex_unlock(&parent_event->child_mutex); | |
11428 | ||
11429 | /* | |
11430 | * Kick perf_poll() for is_event_hup(). | |
11431 | */ | |
11432 | perf_event_wakeup(parent_event); | |
11433 | free_event(child_event); | |
11434 | put_event(parent_event); | |
9b51f66d IM |
11435 | } |
11436 | ||
8dc85d54 | 11437 | static void perf_event_exit_task_context(struct task_struct *child, int ctxn) |
9b51f66d | 11438 | { |
211de6eb | 11439 | struct perf_event_context *child_ctx, *clone_ctx = NULL; |
63b6da39 | 11440 | struct perf_event *child_event, *next; |
63b6da39 PZ |
11441 | |
11442 | WARN_ON_ONCE(child != current); | |
9b51f66d | 11443 | |
6a3351b6 | 11444 | child_ctx = perf_pin_task_context(child, ctxn); |
63b6da39 | 11445 | if (!child_ctx) |
9b51f66d IM |
11446 | return; |
11447 | ||
ad3a37de | 11448 | /* |
6a3351b6 PZ |
11449 | * In order to reduce the amount of tricky in ctx tear-down, we hold |
11450 | * ctx::mutex over the entire thing. This serializes against almost | |
11451 | * everything that wants to access the ctx. | |
11452 | * | |
11453 | * The exception is sys_perf_event_open() / | |
11454 | * perf_event_create_kernel_count() which does find_get_context() | |
11455 | * without ctx::mutex (it cannot because of the move_group double mutex | |
11456 | * lock thing). See the comments in perf_install_in_context(). | |
ad3a37de | 11457 | */ |
6a3351b6 | 11458 | mutex_lock(&child_ctx->mutex); |
c93f7669 PM |
11459 | |
11460 | /* | |
6a3351b6 PZ |
11461 | * In a single ctx::lock section, de-schedule the events and detach the |
11462 | * context from the task such that we cannot ever get it scheduled back | |
11463 | * in. | |
c93f7669 | 11464 | */ |
6a3351b6 | 11465 | raw_spin_lock_irq(&child_ctx->lock); |
487f05e1 | 11466 | task_ctx_sched_out(__get_cpu_context(child_ctx), child_ctx, EVENT_ALL); |
4a1c0f26 | 11467 | |
71a851b4 | 11468 | /* |
63b6da39 PZ |
11469 | * Now that the context is inactive, destroy the task <-> ctx relation |
11470 | * and mark the context dead. | |
71a851b4 | 11471 | */ |
63b6da39 PZ |
11472 | RCU_INIT_POINTER(child->perf_event_ctxp[ctxn], NULL); |
11473 | put_ctx(child_ctx); /* cannot be last */ | |
11474 | WRITE_ONCE(child_ctx->task, TASK_TOMBSTONE); | |
11475 | put_task_struct(current); /* cannot be last */ | |
4a1c0f26 | 11476 | |
211de6eb | 11477 | clone_ctx = unclone_ctx(child_ctx); |
6a3351b6 | 11478 | raw_spin_unlock_irq(&child_ctx->lock); |
9f498cc5 | 11479 | |
211de6eb PZ |
11480 | if (clone_ctx) |
11481 | put_ctx(clone_ctx); | |
4a1c0f26 | 11482 | |
9f498cc5 | 11483 | /* |
cdd6c482 IM |
11484 | * Report the task dead after unscheduling the events so that we |
11485 | * won't get any samples after PERF_RECORD_EXIT. We can however still | |
11486 | * get a few PERF_RECORD_READ events. | |
9f498cc5 | 11487 | */ |
cdd6c482 | 11488 | perf_event_task(child, child_ctx, 0); |
a63eaf34 | 11489 | |
ebf905fc | 11490 | list_for_each_entry_safe(child_event, next, &child_ctx->event_list, event_entry) |
8ba289b8 | 11491 | perf_event_exit_event(child_event, child_ctx, child); |
8bc20959 | 11492 | |
a63eaf34 PM |
11493 | mutex_unlock(&child_ctx->mutex); |
11494 | ||
11495 | put_ctx(child_ctx); | |
9b51f66d IM |
11496 | } |
11497 | ||
8dc85d54 PZ |
11498 | /* |
11499 | * When a child task exits, feed back event values to parent events. | |
79c9ce57 PZ |
11500 | * |
11501 | * Can be called with cred_guard_mutex held when called from | |
11502 | * install_exec_creds(). | |
8dc85d54 PZ |
11503 | */ |
11504 | void perf_event_exit_task(struct task_struct *child) | |
11505 | { | |
8882135b | 11506 | struct perf_event *event, *tmp; |
8dc85d54 PZ |
11507 | int ctxn; |
11508 | ||
8882135b PZ |
11509 | mutex_lock(&child->perf_event_mutex); |
11510 | list_for_each_entry_safe(event, tmp, &child->perf_event_list, | |
11511 | owner_entry) { | |
11512 | list_del_init(&event->owner_entry); | |
11513 | ||
11514 | /* | |
11515 | * Ensure the list deletion is visible before we clear | |
11516 | * the owner, closes a race against perf_release() where | |
11517 | * we need to serialize on the owner->perf_event_mutex. | |
11518 | */ | |
f47c02c0 | 11519 | smp_store_release(&event->owner, NULL); |
8882135b PZ |
11520 | } |
11521 | mutex_unlock(&child->perf_event_mutex); | |
11522 | ||
8dc85d54 PZ |
11523 | for_each_task_context_nr(ctxn) |
11524 | perf_event_exit_task_context(child, ctxn); | |
4e93ad60 JO |
11525 | |
11526 | /* | |
11527 | * The perf_event_exit_task_context calls perf_event_task | |
11528 | * with child's task_ctx, which generates EXIT events for | |
11529 | * child contexts and sets child->perf_event_ctxp[] to NULL. | |
11530 | * At this point we need to send EXIT events to cpu contexts. | |
11531 | */ | |
11532 | perf_event_task(child, NULL, 0); | |
8dc85d54 PZ |
11533 | } |
11534 | ||
889ff015 FW |
11535 | static void perf_free_event(struct perf_event *event, |
11536 | struct perf_event_context *ctx) | |
11537 | { | |
11538 | struct perf_event *parent = event->parent; | |
11539 | ||
11540 | if (WARN_ON_ONCE(!parent)) | |
11541 | return; | |
11542 | ||
11543 | mutex_lock(&parent->child_mutex); | |
11544 | list_del_init(&event->child_list); | |
11545 | mutex_unlock(&parent->child_mutex); | |
11546 | ||
a6fa941d | 11547 | put_event(parent); |
889ff015 | 11548 | |
652884fe | 11549 | raw_spin_lock_irq(&ctx->lock); |
8a49542c | 11550 | perf_group_detach(event); |
889ff015 | 11551 | list_del_event(event, ctx); |
652884fe | 11552 | raw_spin_unlock_irq(&ctx->lock); |
889ff015 FW |
11553 | free_event(event); |
11554 | } | |
11555 | ||
bbbee908 | 11556 | /* |
1cf8dfe8 PZ |
11557 | * Free a context as created by inheritance by perf_event_init_task() below, |
11558 | * used by fork() in case of fail. | |
652884fe | 11559 | * |
1cf8dfe8 PZ |
11560 | * Even though the task has never lived, the context and events have been |
11561 | * exposed through the child_list, so we must take care tearing it all down. | |
bbbee908 | 11562 | */ |
cdd6c482 | 11563 | void perf_event_free_task(struct task_struct *task) |
bbbee908 | 11564 | { |
8dc85d54 | 11565 | struct perf_event_context *ctx; |
cdd6c482 | 11566 | struct perf_event *event, *tmp; |
8dc85d54 | 11567 | int ctxn; |
bbbee908 | 11568 | |
8dc85d54 PZ |
11569 | for_each_task_context_nr(ctxn) { |
11570 | ctx = task->perf_event_ctxp[ctxn]; | |
11571 | if (!ctx) | |
11572 | continue; | |
bbbee908 | 11573 | |
8dc85d54 | 11574 | mutex_lock(&ctx->mutex); |
e552a838 PZ |
11575 | raw_spin_lock_irq(&ctx->lock); |
11576 | /* | |
11577 | * Destroy the task <-> ctx relation and mark the context dead. | |
11578 | * | |
11579 | * This is important because even though the task hasn't been | |
11580 | * exposed yet the context has been (through child_list). | |
11581 | */ | |
11582 | RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], NULL); | |
11583 | WRITE_ONCE(ctx->task, TASK_TOMBSTONE); | |
11584 | put_task_struct(task); /* cannot be last */ | |
11585 | raw_spin_unlock_irq(&ctx->lock); | |
bbbee908 | 11586 | |
15121c78 | 11587 | list_for_each_entry_safe(event, tmp, &ctx->event_list, event_entry) |
8dc85d54 | 11588 | perf_free_event(event, ctx); |
bbbee908 | 11589 | |
8dc85d54 | 11590 | mutex_unlock(&ctx->mutex); |
1cf8dfe8 PZ |
11591 | |
11592 | /* | |
11593 | * perf_event_release_kernel() could've stolen some of our | |
11594 | * child events and still have them on its free_list. In that | |
11595 | * case we must wait for these events to have been freed (in | |
11596 | * particular all their references to this task must've been | |
11597 | * dropped). | |
11598 | * | |
11599 | * Without this copy_process() will unconditionally free this | |
11600 | * task (irrespective of its reference count) and | |
11601 | * _free_event()'s put_task_struct(event->hw.target) will be a | |
11602 | * use-after-free. | |
11603 | * | |
11604 | * Wait for all events to drop their context reference. | |
11605 | */ | |
11606 | wait_var_event(&ctx->refcount, refcount_read(&ctx->refcount) == 1); | |
11607 | put_ctx(ctx); /* must be last */ | |
8dc85d54 | 11608 | } |
889ff015 FW |
11609 | } |
11610 | ||
4e231c79 PZ |
11611 | void perf_event_delayed_put(struct task_struct *task) |
11612 | { | |
11613 | int ctxn; | |
11614 | ||
11615 | for_each_task_context_nr(ctxn) | |
11616 | WARN_ON_ONCE(task->perf_event_ctxp[ctxn]); | |
11617 | } | |
11618 | ||
e03e7ee3 | 11619 | struct file *perf_event_get(unsigned int fd) |
ffe8690c | 11620 | { |
02e5ad97 | 11621 | struct file *file = fget(fd); |
e03e7ee3 AS |
11622 | if (!file) |
11623 | return ERR_PTR(-EBADF); | |
ffe8690c | 11624 | |
e03e7ee3 AS |
11625 | if (file->f_op != &perf_fops) { |
11626 | fput(file); | |
11627 | return ERR_PTR(-EBADF); | |
11628 | } | |
ffe8690c | 11629 | |
e03e7ee3 | 11630 | return file; |
ffe8690c KX |
11631 | } |
11632 | ||
f8d959a5 YS |
11633 | const struct perf_event *perf_get_event(struct file *file) |
11634 | { | |
11635 | if (file->f_op != &perf_fops) | |
11636 | return ERR_PTR(-EINVAL); | |
11637 | ||
11638 | return file->private_data; | |
11639 | } | |
11640 | ||
ffe8690c KX |
11641 | const struct perf_event_attr *perf_event_attrs(struct perf_event *event) |
11642 | { | |
11643 | if (!event) | |
11644 | return ERR_PTR(-EINVAL); | |
11645 | ||
11646 | return &event->attr; | |
11647 | } | |
11648 | ||
97dee4f3 | 11649 | /* |
788faab7 | 11650 | * Inherit an event from parent task to child task. |
d8a8cfc7 PZ |
11651 | * |
11652 | * Returns: | |
11653 | * - valid pointer on success | |
11654 | * - NULL for orphaned events | |
11655 | * - IS_ERR() on error | |
97dee4f3 PZ |
11656 | */ |
11657 | static struct perf_event * | |
11658 | inherit_event(struct perf_event *parent_event, | |
11659 | struct task_struct *parent, | |
11660 | struct perf_event_context *parent_ctx, | |
11661 | struct task_struct *child, | |
11662 | struct perf_event *group_leader, | |
11663 | struct perf_event_context *child_ctx) | |
11664 | { | |
8ca2bd41 | 11665 | enum perf_event_state parent_state = parent_event->state; |
97dee4f3 | 11666 | struct perf_event *child_event; |
cee010ec | 11667 | unsigned long flags; |
97dee4f3 PZ |
11668 | |
11669 | /* | |
11670 | * Instead of creating recursive hierarchies of events, | |
11671 | * we link inherited events back to the original parent, | |
11672 | * which has a filp for sure, which we use as the reference | |
11673 | * count: | |
11674 | */ | |
11675 | if (parent_event->parent) | |
11676 | parent_event = parent_event->parent; | |
11677 | ||
11678 | child_event = perf_event_alloc(&parent_event->attr, | |
11679 | parent_event->cpu, | |
d580ff86 | 11680 | child, |
97dee4f3 | 11681 | group_leader, parent_event, |
79dff51e | 11682 | NULL, NULL, -1); |
97dee4f3 PZ |
11683 | if (IS_ERR(child_event)) |
11684 | return child_event; | |
a6fa941d | 11685 | |
313ccb96 JO |
11686 | |
11687 | if ((child_event->attach_state & PERF_ATTACH_TASK_DATA) && | |
11688 | !child_ctx->task_ctx_data) { | |
11689 | struct pmu *pmu = child_event->pmu; | |
11690 | ||
11691 | child_ctx->task_ctx_data = kzalloc(pmu->task_ctx_size, | |
11692 | GFP_KERNEL); | |
11693 | if (!child_ctx->task_ctx_data) { | |
11694 | free_event(child_event); | |
11695 | return NULL; | |
11696 | } | |
11697 | } | |
11698 | ||
c6e5b732 PZ |
11699 | /* |
11700 | * is_orphaned_event() and list_add_tail(&parent_event->child_list) | |
11701 | * must be under the same lock in order to serialize against | |
11702 | * perf_event_release_kernel(), such that either we must observe | |
11703 | * is_orphaned_event() or they will observe us on the child_list. | |
11704 | */ | |
11705 | mutex_lock(&parent_event->child_mutex); | |
fadfe7be JO |
11706 | if (is_orphaned_event(parent_event) || |
11707 | !atomic_long_inc_not_zero(&parent_event->refcount)) { | |
c6e5b732 | 11708 | mutex_unlock(&parent_event->child_mutex); |
313ccb96 | 11709 | /* task_ctx_data is freed with child_ctx */ |
a6fa941d AV |
11710 | free_event(child_event); |
11711 | return NULL; | |
11712 | } | |
11713 | ||
97dee4f3 PZ |
11714 | get_ctx(child_ctx); |
11715 | ||
11716 | /* | |
11717 | * Make the child state follow the state of the parent event, | |
11718 | * not its attr.disabled bit. We hold the parent's mutex, | |
11719 | * so we won't race with perf_event_{en, dis}able_family. | |
11720 | */ | |
1929def9 | 11721 | if (parent_state >= PERF_EVENT_STATE_INACTIVE) |
97dee4f3 PZ |
11722 | child_event->state = PERF_EVENT_STATE_INACTIVE; |
11723 | else | |
11724 | child_event->state = PERF_EVENT_STATE_OFF; | |
11725 | ||
11726 | if (parent_event->attr.freq) { | |
11727 | u64 sample_period = parent_event->hw.sample_period; | |
11728 | struct hw_perf_event *hwc = &child_event->hw; | |
11729 | ||
11730 | hwc->sample_period = sample_period; | |
11731 | hwc->last_period = sample_period; | |
11732 | ||
11733 | local64_set(&hwc->period_left, sample_period); | |
11734 | } | |
11735 | ||
11736 | child_event->ctx = child_ctx; | |
11737 | child_event->overflow_handler = parent_event->overflow_handler; | |
4dc0da86 AK |
11738 | child_event->overflow_handler_context |
11739 | = parent_event->overflow_handler_context; | |
97dee4f3 | 11740 | |
614b6780 TG |
11741 | /* |
11742 | * Precalculate sample_data sizes | |
11743 | */ | |
11744 | perf_event__header_size(child_event); | |
6844c09d | 11745 | perf_event__id_header_size(child_event); |
614b6780 | 11746 | |
97dee4f3 PZ |
11747 | /* |
11748 | * Link it up in the child's context: | |
11749 | */ | |
cee010ec | 11750 | raw_spin_lock_irqsave(&child_ctx->lock, flags); |
97dee4f3 | 11751 | add_event_to_ctx(child_event, child_ctx); |
cee010ec | 11752 | raw_spin_unlock_irqrestore(&child_ctx->lock, flags); |
97dee4f3 | 11753 | |
97dee4f3 PZ |
11754 | /* |
11755 | * Link this into the parent event's child list | |
11756 | */ | |
97dee4f3 PZ |
11757 | list_add_tail(&child_event->child_list, &parent_event->child_list); |
11758 | mutex_unlock(&parent_event->child_mutex); | |
11759 | ||
11760 | return child_event; | |
11761 | } | |
11762 | ||
d8a8cfc7 PZ |
11763 | /* |
11764 | * Inherits an event group. | |
11765 | * | |
11766 | * This will quietly suppress orphaned events; !inherit_event() is not an error. | |
11767 | * This matches with perf_event_release_kernel() removing all child events. | |
11768 | * | |
11769 | * Returns: | |
11770 | * - 0 on success | |
11771 | * - <0 on error | |
11772 | */ | |
97dee4f3 PZ |
11773 | static int inherit_group(struct perf_event *parent_event, |
11774 | struct task_struct *parent, | |
11775 | struct perf_event_context *parent_ctx, | |
11776 | struct task_struct *child, | |
11777 | struct perf_event_context *child_ctx) | |
11778 | { | |
11779 | struct perf_event *leader; | |
11780 | struct perf_event *sub; | |
11781 | struct perf_event *child_ctr; | |
11782 | ||
11783 | leader = inherit_event(parent_event, parent, parent_ctx, | |
11784 | child, NULL, child_ctx); | |
11785 | if (IS_ERR(leader)) | |
11786 | return PTR_ERR(leader); | |
d8a8cfc7 PZ |
11787 | /* |
11788 | * @leader can be NULL here because of is_orphaned_event(). In this | |
11789 | * case inherit_event() will create individual events, similar to what | |
11790 | * perf_group_detach() would do anyway. | |
11791 | */ | |
edb39592 | 11792 | for_each_sibling_event(sub, parent_event) { |
97dee4f3 PZ |
11793 | child_ctr = inherit_event(sub, parent, parent_ctx, |
11794 | child, leader, child_ctx); | |
11795 | if (IS_ERR(child_ctr)) | |
11796 | return PTR_ERR(child_ctr); | |
11797 | } | |
11798 | return 0; | |
889ff015 FW |
11799 | } |
11800 | ||
d8a8cfc7 PZ |
11801 | /* |
11802 | * Creates the child task context and tries to inherit the event-group. | |
11803 | * | |
11804 | * Clears @inherited_all on !attr.inherited or error. Note that we'll leave | |
11805 | * inherited_all set when we 'fail' to inherit an orphaned event; this is | |
11806 | * consistent with perf_event_release_kernel() removing all child events. | |
11807 | * | |
11808 | * Returns: | |
11809 | * - 0 on success | |
11810 | * - <0 on error | |
11811 | */ | |
889ff015 FW |
11812 | static int |
11813 | inherit_task_group(struct perf_event *event, struct task_struct *parent, | |
11814 | struct perf_event_context *parent_ctx, | |
8dc85d54 | 11815 | struct task_struct *child, int ctxn, |
889ff015 FW |
11816 | int *inherited_all) |
11817 | { | |
11818 | int ret; | |
8dc85d54 | 11819 | struct perf_event_context *child_ctx; |
889ff015 FW |
11820 | |
11821 | if (!event->attr.inherit) { | |
11822 | *inherited_all = 0; | |
11823 | return 0; | |
bbbee908 PZ |
11824 | } |
11825 | ||
fe4b04fa | 11826 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 FW |
11827 | if (!child_ctx) { |
11828 | /* | |
11829 | * This is executed from the parent task context, so | |
11830 | * inherit events that have been marked for cloning. | |
11831 | * First allocate and initialize a context for the | |
11832 | * child. | |
11833 | */ | |
734df5ab | 11834 | child_ctx = alloc_perf_context(parent_ctx->pmu, child); |
889ff015 FW |
11835 | if (!child_ctx) |
11836 | return -ENOMEM; | |
bbbee908 | 11837 | |
8dc85d54 | 11838 | child->perf_event_ctxp[ctxn] = child_ctx; |
889ff015 FW |
11839 | } |
11840 | ||
11841 | ret = inherit_group(event, parent, parent_ctx, | |
11842 | child, child_ctx); | |
11843 | ||
11844 | if (ret) | |
11845 | *inherited_all = 0; | |
11846 | ||
11847 | return ret; | |
bbbee908 PZ |
11848 | } |
11849 | ||
9b51f66d | 11850 | /* |
cdd6c482 | 11851 | * Initialize the perf_event context in task_struct |
9b51f66d | 11852 | */ |
985c8dcb | 11853 | static int perf_event_init_context(struct task_struct *child, int ctxn) |
9b51f66d | 11854 | { |
889ff015 | 11855 | struct perf_event_context *child_ctx, *parent_ctx; |
cdd6c482 IM |
11856 | struct perf_event_context *cloned_ctx; |
11857 | struct perf_event *event; | |
9b51f66d | 11858 | struct task_struct *parent = current; |
564c2b21 | 11859 | int inherited_all = 1; |
dddd3379 | 11860 | unsigned long flags; |
6ab423e0 | 11861 | int ret = 0; |
9b51f66d | 11862 | |
8dc85d54 | 11863 | if (likely(!parent->perf_event_ctxp[ctxn])) |
6ab423e0 PZ |
11864 | return 0; |
11865 | ||
ad3a37de | 11866 | /* |
25346b93 PM |
11867 | * If the parent's context is a clone, pin it so it won't get |
11868 | * swapped under us. | |
ad3a37de | 11869 | */ |
8dc85d54 | 11870 | parent_ctx = perf_pin_task_context(parent, ctxn); |
ffb4ef21 PZ |
11871 | if (!parent_ctx) |
11872 | return 0; | |
25346b93 | 11873 | |
ad3a37de PM |
11874 | /* |
11875 | * No need to check if parent_ctx != NULL here; since we saw | |
11876 | * it non-NULL earlier, the only reason for it to become NULL | |
11877 | * is if we exit, and since we're currently in the middle of | |
11878 | * a fork we can't be exiting at the same time. | |
11879 | */ | |
ad3a37de | 11880 | |
9b51f66d IM |
11881 | /* |
11882 | * Lock the parent list. No need to lock the child - not PID | |
11883 | * hashed yet and not running, so nobody can access it. | |
11884 | */ | |
d859e29f | 11885 | mutex_lock(&parent_ctx->mutex); |
9b51f66d IM |
11886 | |
11887 | /* | |
11888 | * We dont have to disable NMIs - we are only looking at | |
11889 | * the list, not manipulating it: | |
11890 | */ | |
6e6804d2 | 11891 | perf_event_groups_for_each(event, &parent_ctx->pinned_groups) { |
8dc85d54 PZ |
11892 | ret = inherit_task_group(event, parent, parent_ctx, |
11893 | child, ctxn, &inherited_all); | |
889ff015 | 11894 | if (ret) |
e7cc4865 | 11895 | goto out_unlock; |
889ff015 | 11896 | } |
b93f7978 | 11897 | |
dddd3379 TG |
11898 | /* |
11899 | * We can't hold ctx->lock when iterating the ->flexible_group list due | |
11900 | * to allocations, but we need to prevent rotation because | |
11901 | * rotate_ctx() will change the list from interrupt context. | |
11902 | */ | |
11903 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); | |
11904 | parent_ctx->rotate_disable = 1; | |
11905 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); | |
11906 | ||
6e6804d2 | 11907 | perf_event_groups_for_each(event, &parent_ctx->flexible_groups) { |
8dc85d54 PZ |
11908 | ret = inherit_task_group(event, parent, parent_ctx, |
11909 | child, ctxn, &inherited_all); | |
889ff015 | 11910 | if (ret) |
e7cc4865 | 11911 | goto out_unlock; |
564c2b21 PM |
11912 | } |
11913 | ||
dddd3379 TG |
11914 | raw_spin_lock_irqsave(&parent_ctx->lock, flags); |
11915 | parent_ctx->rotate_disable = 0; | |
dddd3379 | 11916 | |
8dc85d54 | 11917 | child_ctx = child->perf_event_ctxp[ctxn]; |
889ff015 | 11918 | |
05cbaa28 | 11919 | if (child_ctx && inherited_all) { |
564c2b21 PM |
11920 | /* |
11921 | * Mark the child context as a clone of the parent | |
11922 | * context, or of whatever the parent is a clone of. | |
c5ed5145 PZ |
11923 | * |
11924 | * Note that if the parent is a clone, the holding of | |
11925 | * parent_ctx->lock avoids it from being uncloned. | |
564c2b21 | 11926 | */ |
c5ed5145 | 11927 | cloned_ctx = parent_ctx->parent_ctx; |
ad3a37de PM |
11928 | if (cloned_ctx) { |
11929 | child_ctx->parent_ctx = cloned_ctx; | |
25346b93 | 11930 | child_ctx->parent_gen = parent_ctx->parent_gen; |
564c2b21 PM |
11931 | } else { |
11932 | child_ctx->parent_ctx = parent_ctx; | |
11933 | child_ctx->parent_gen = parent_ctx->generation; | |
11934 | } | |
11935 | get_ctx(child_ctx->parent_ctx); | |
9b51f66d IM |
11936 | } |
11937 | ||
c5ed5145 | 11938 | raw_spin_unlock_irqrestore(&parent_ctx->lock, flags); |
e7cc4865 | 11939 | out_unlock: |
d859e29f | 11940 | mutex_unlock(&parent_ctx->mutex); |
6ab423e0 | 11941 | |
25346b93 | 11942 | perf_unpin_context(parent_ctx); |
fe4b04fa | 11943 | put_ctx(parent_ctx); |
ad3a37de | 11944 | |
6ab423e0 | 11945 | return ret; |
9b51f66d IM |
11946 | } |
11947 | ||
8dc85d54 PZ |
11948 | /* |
11949 | * Initialize the perf_event context in task_struct | |
11950 | */ | |
11951 | int perf_event_init_task(struct task_struct *child) | |
11952 | { | |
11953 | int ctxn, ret; | |
11954 | ||
8550d7cb ON |
11955 | memset(child->perf_event_ctxp, 0, sizeof(child->perf_event_ctxp)); |
11956 | mutex_init(&child->perf_event_mutex); | |
11957 | INIT_LIST_HEAD(&child->perf_event_list); | |
11958 | ||
8dc85d54 PZ |
11959 | for_each_task_context_nr(ctxn) { |
11960 | ret = perf_event_init_context(child, ctxn); | |
6c72e350 PZ |
11961 | if (ret) { |
11962 | perf_event_free_task(child); | |
8dc85d54 | 11963 | return ret; |
6c72e350 | 11964 | } |
8dc85d54 PZ |
11965 | } |
11966 | ||
11967 | return 0; | |
11968 | } | |
11969 | ||
220b140b PM |
11970 | static void __init perf_event_init_all_cpus(void) |
11971 | { | |
b28ab83c | 11972 | struct swevent_htable *swhash; |
220b140b | 11973 | int cpu; |
220b140b | 11974 | |
a63fbed7 TG |
11975 | zalloc_cpumask_var(&perf_online_mask, GFP_KERNEL); |
11976 | ||
220b140b | 11977 | for_each_possible_cpu(cpu) { |
b28ab83c PZ |
11978 | swhash = &per_cpu(swevent_htable, cpu); |
11979 | mutex_init(&swhash->hlist_mutex); | |
2fde4f94 | 11980 | INIT_LIST_HEAD(&per_cpu(active_ctx_list, cpu)); |
f2fb6bef KL |
11981 | |
11982 | INIT_LIST_HEAD(&per_cpu(pmu_sb_events.list, cpu)); | |
11983 | raw_spin_lock_init(&per_cpu(pmu_sb_events.lock, cpu)); | |
e48c1788 | 11984 | |
058fe1c0 DCC |
11985 | #ifdef CONFIG_CGROUP_PERF |
11986 | INIT_LIST_HEAD(&per_cpu(cgrp_cpuctx_list, cpu)); | |
11987 | #endif | |
e48c1788 | 11988 | INIT_LIST_HEAD(&per_cpu(sched_cb_list, cpu)); |
220b140b PM |
11989 | } |
11990 | } | |
11991 | ||
d18bf422 | 11992 | static void perf_swevent_init_cpu(unsigned int cpu) |
0793a61d | 11993 | { |
108b02cf | 11994 | struct swevent_htable *swhash = &per_cpu(swevent_htable, cpu); |
0793a61d | 11995 | |
b28ab83c | 11996 | mutex_lock(&swhash->hlist_mutex); |
059fcd8c | 11997 | if (swhash->hlist_refcount > 0 && !swevent_hlist_deref(swhash)) { |
76e1d904 FW |
11998 | struct swevent_hlist *hlist; |
11999 | ||
b28ab83c PZ |
12000 | hlist = kzalloc_node(sizeof(*hlist), GFP_KERNEL, cpu_to_node(cpu)); |
12001 | WARN_ON(!hlist); | |
12002 | rcu_assign_pointer(swhash->swevent_hlist, hlist); | |
76e1d904 | 12003 | } |
b28ab83c | 12004 | mutex_unlock(&swhash->hlist_mutex); |
0793a61d TG |
12005 | } |
12006 | ||
2965faa5 | 12007 | #if defined CONFIG_HOTPLUG_CPU || defined CONFIG_KEXEC_CORE |
108b02cf | 12008 | static void __perf_event_exit_context(void *__info) |
0793a61d | 12009 | { |
108b02cf | 12010 | struct perf_event_context *ctx = __info; |
fae3fde6 PZ |
12011 | struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); |
12012 | struct perf_event *event; | |
0793a61d | 12013 | |
fae3fde6 | 12014 | raw_spin_lock(&ctx->lock); |
0ee098c9 | 12015 | ctx_sched_out(ctx, cpuctx, EVENT_TIME); |
fae3fde6 | 12016 | list_for_each_entry(event, &ctx->event_list, event_entry) |
45a0e07a | 12017 | __perf_remove_from_context(event, cpuctx, ctx, (void *)DETACH_GROUP); |
fae3fde6 | 12018 | raw_spin_unlock(&ctx->lock); |
0793a61d | 12019 | } |
108b02cf PZ |
12020 | |
12021 | static void perf_event_exit_cpu_context(int cpu) | |
12022 | { | |
a63fbed7 | 12023 | struct perf_cpu_context *cpuctx; |
108b02cf PZ |
12024 | struct perf_event_context *ctx; |
12025 | struct pmu *pmu; | |
108b02cf | 12026 | |
a63fbed7 TG |
12027 | mutex_lock(&pmus_lock); |
12028 | list_for_each_entry(pmu, &pmus, entry) { | |
12029 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
12030 | ctx = &cpuctx->ctx; | |
108b02cf PZ |
12031 | |
12032 | mutex_lock(&ctx->mutex); | |
12033 | smp_call_function_single(cpu, __perf_event_exit_context, ctx, 1); | |
a63fbed7 | 12034 | cpuctx->online = 0; |
108b02cf PZ |
12035 | mutex_unlock(&ctx->mutex); |
12036 | } | |
a63fbed7 TG |
12037 | cpumask_clear_cpu(cpu, perf_online_mask); |
12038 | mutex_unlock(&pmus_lock); | |
108b02cf | 12039 | } |
00e16c3d TG |
12040 | #else |
12041 | ||
12042 | static void perf_event_exit_cpu_context(int cpu) { } | |
12043 | ||
12044 | #endif | |
108b02cf | 12045 | |
a63fbed7 TG |
12046 | int perf_event_init_cpu(unsigned int cpu) |
12047 | { | |
12048 | struct perf_cpu_context *cpuctx; | |
12049 | struct perf_event_context *ctx; | |
12050 | struct pmu *pmu; | |
12051 | ||
12052 | perf_swevent_init_cpu(cpu); | |
12053 | ||
12054 | mutex_lock(&pmus_lock); | |
12055 | cpumask_set_cpu(cpu, perf_online_mask); | |
12056 | list_for_each_entry(pmu, &pmus, entry) { | |
12057 | cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); | |
12058 | ctx = &cpuctx->ctx; | |
12059 | ||
12060 | mutex_lock(&ctx->mutex); | |
12061 | cpuctx->online = 1; | |
12062 | mutex_unlock(&ctx->mutex); | |
12063 | } | |
12064 | mutex_unlock(&pmus_lock); | |
12065 | ||
12066 | return 0; | |
12067 | } | |
12068 | ||
00e16c3d | 12069 | int perf_event_exit_cpu(unsigned int cpu) |
0793a61d | 12070 | { |
e3703f8c | 12071 | perf_event_exit_cpu_context(cpu); |
00e16c3d | 12072 | return 0; |
0793a61d | 12073 | } |
0793a61d | 12074 | |
c277443c PZ |
12075 | static int |
12076 | perf_reboot(struct notifier_block *notifier, unsigned long val, void *v) | |
12077 | { | |
12078 | int cpu; | |
12079 | ||
12080 | for_each_online_cpu(cpu) | |
12081 | perf_event_exit_cpu(cpu); | |
12082 | ||
12083 | return NOTIFY_OK; | |
12084 | } | |
12085 | ||
12086 | /* | |
12087 | * Run the perf reboot notifier at the very last possible moment so that | |
12088 | * the generic watchdog code runs as long as possible. | |
12089 | */ | |
12090 | static struct notifier_block perf_reboot_notifier = { | |
12091 | .notifier_call = perf_reboot, | |
12092 | .priority = INT_MIN, | |
12093 | }; | |
12094 | ||
cdd6c482 | 12095 | void __init perf_event_init(void) |
0793a61d | 12096 | { |
3c502e7a JW |
12097 | int ret; |
12098 | ||
2e80a82a PZ |
12099 | idr_init(&pmu_idr); |
12100 | ||
220b140b | 12101 | perf_event_init_all_cpus(); |
b0a873eb | 12102 | init_srcu_struct(&pmus_srcu); |
2e80a82a PZ |
12103 | perf_pmu_register(&perf_swevent, "software", PERF_TYPE_SOFTWARE); |
12104 | perf_pmu_register(&perf_cpu_clock, NULL, -1); | |
12105 | perf_pmu_register(&perf_task_clock, NULL, -1); | |
b0a873eb | 12106 | perf_tp_register(); |
00e16c3d | 12107 | perf_event_init_cpu(smp_processor_id()); |
c277443c | 12108 | register_reboot_notifier(&perf_reboot_notifier); |
3c502e7a JW |
12109 | |
12110 | ret = init_hw_breakpoint(); | |
12111 | WARN(ret, "hw_breakpoint initialization failed with: %d", ret); | |
b2029520 | 12112 | |
b01c3a00 JO |
12113 | /* |
12114 | * Build time assertion that we keep the data_head at the intended | |
12115 | * location. IOW, validation we got the __reserved[] size right. | |
12116 | */ | |
12117 | BUILD_BUG_ON((offsetof(struct perf_event_mmap_page, data_head)) | |
12118 | != 1024); | |
0793a61d | 12119 | } |
abe43400 | 12120 | |
fd979c01 CS |
12121 | ssize_t perf_event_sysfs_show(struct device *dev, struct device_attribute *attr, |
12122 | char *page) | |
12123 | { | |
12124 | struct perf_pmu_events_attr *pmu_attr = | |
12125 | container_of(attr, struct perf_pmu_events_attr, attr); | |
12126 | ||
12127 | if (pmu_attr->event_str) | |
12128 | return sprintf(page, "%s\n", pmu_attr->event_str); | |
12129 | ||
12130 | return 0; | |
12131 | } | |
675965b0 | 12132 | EXPORT_SYMBOL_GPL(perf_event_sysfs_show); |
fd979c01 | 12133 | |
abe43400 PZ |
12134 | static int __init perf_event_sysfs_init(void) |
12135 | { | |
12136 | struct pmu *pmu; | |
12137 | int ret; | |
12138 | ||
12139 | mutex_lock(&pmus_lock); | |
12140 | ||
12141 | ret = bus_register(&pmu_bus); | |
12142 | if (ret) | |
12143 | goto unlock; | |
12144 | ||
12145 | list_for_each_entry(pmu, &pmus, entry) { | |
12146 | if (!pmu->name || pmu->type < 0) | |
12147 | continue; | |
12148 | ||
12149 | ret = pmu_dev_alloc(pmu); | |
12150 | WARN(ret, "Failed to register pmu: %s, reason %d\n", pmu->name, ret); | |
12151 | } | |
12152 | pmu_bus_running = 1; | |
12153 | ret = 0; | |
12154 | ||
12155 | unlock: | |
12156 | mutex_unlock(&pmus_lock); | |
12157 | ||
12158 | return ret; | |
12159 | } | |
12160 | device_initcall(perf_event_sysfs_init); | |
e5d1367f SE |
12161 | |
12162 | #ifdef CONFIG_CGROUP_PERF | |
eb95419b TH |
12163 | static struct cgroup_subsys_state * |
12164 | perf_cgroup_css_alloc(struct cgroup_subsys_state *parent_css) | |
e5d1367f SE |
12165 | { |
12166 | struct perf_cgroup *jc; | |
e5d1367f | 12167 | |
1b15d055 | 12168 | jc = kzalloc(sizeof(*jc), GFP_KERNEL); |
e5d1367f SE |
12169 | if (!jc) |
12170 | return ERR_PTR(-ENOMEM); | |
12171 | ||
e5d1367f SE |
12172 | jc->info = alloc_percpu(struct perf_cgroup_info); |
12173 | if (!jc->info) { | |
12174 | kfree(jc); | |
12175 | return ERR_PTR(-ENOMEM); | |
12176 | } | |
12177 | ||
e5d1367f SE |
12178 | return &jc->css; |
12179 | } | |
12180 | ||
eb95419b | 12181 | static void perf_cgroup_css_free(struct cgroup_subsys_state *css) |
e5d1367f | 12182 | { |
eb95419b TH |
12183 | struct perf_cgroup *jc = container_of(css, struct perf_cgroup, css); |
12184 | ||
e5d1367f SE |
12185 | free_percpu(jc->info); |
12186 | kfree(jc); | |
12187 | } | |
12188 | ||
12189 | static int __perf_cgroup_move(void *info) | |
12190 | { | |
12191 | struct task_struct *task = info; | |
ddaaf4e2 | 12192 | rcu_read_lock(); |
e5d1367f | 12193 | perf_cgroup_switch(task, PERF_CGROUP_SWOUT | PERF_CGROUP_SWIN); |
ddaaf4e2 | 12194 | rcu_read_unlock(); |
e5d1367f SE |
12195 | return 0; |
12196 | } | |
12197 | ||
1f7dd3e5 | 12198 | static void perf_cgroup_attach(struct cgroup_taskset *tset) |
e5d1367f | 12199 | { |
bb9d97b6 | 12200 | struct task_struct *task; |
1f7dd3e5 | 12201 | struct cgroup_subsys_state *css; |
bb9d97b6 | 12202 | |
1f7dd3e5 | 12203 | cgroup_taskset_for_each(task, css, tset) |
bb9d97b6 | 12204 | task_function_call(task, __perf_cgroup_move, task); |
e5d1367f SE |
12205 | } |
12206 | ||
073219e9 | 12207 | struct cgroup_subsys perf_event_cgrp_subsys = { |
92fb9748 TH |
12208 | .css_alloc = perf_cgroup_css_alloc, |
12209 | .css_free = perf_cgroup_css_free, | |
bb9d97b6 | 12210 | .attach = perf_cgroup_attach, |
968ebff1 TH |
12211 | /* |
12212 | * Implicitly enable on dfl hierarchy so that perf events can | |
12213 | * always be filtered by cgroup2 path as long as perf_event | |
12214 | * controller is not mounted on a legacy hierarchy. | |
12215 | */ | |
12216 | .implicit_on_dfl = true, | |
8cfd8147 | 12217 | .threaded = true, |
e5d1367f SE |
12218 | }; |
12219 | #endif /* CONFIG_CGROUP_PERF */ |