xref: /linux/tools/perf/util/evlist.c (revision 42fc2e9ef9603a7948aaa4ffd8dfb94b30294ad8)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2011, Red Hat Inc, Arnaldo Carvalho de Melo <acme@redhat.com>
4  *
5  * Parts came from builtin-{top,stat,record}.c, see those files for further
6  * copyright notes.
7  */
8 #include <api/fs/fs.h>
9 #include <errno.h>
10 #include <inttypes.h>
11 #include <poll.h>
12 #include "cpumap.h"
13 #include "thread_map.h"
14 #include "target.h"
15 #include "evlist.h"
16 #include "evsel.h"
17 #include "debug.h"
18 #include "units.h"
19 #include "asm/bug.h"
20 #include "bpf-event.h"
21 #include <signal.h>
22 #include <unistd.h>
23 
24 #include "parse-events.h"
25 #include <subcmd/parse-options.h>
26 
27 #include <fcntl.h>
28 #include <sys/ioctl.h>
29 #include <sys/mman.h>
30 
31 #include <linux/bitops.h>
32 #include <linux/hash.h>
33 #include <linux/log2.h>
34 #include <linux/err.h>
35 #include <linux/zalloc.h>
36 #include <perf/evlist.h>
37 #include <perf/evsel.h>
38 #include <perf/cpumap.h>
39 
40 #ifdef LACKS_SIGQUEUE_PROTOTYPE
41 int sigqueue(pid_t pid, int sig, const union sigval value);
42 #endif
43 
44 #define FD(e, x, y) (*(int *)xyarray__entry(e->core.fd, x, y))
45 #define SID(e, x, y) xyarray__entry(e->sample_id, x, y)
46 
47 void evlist__init(struct evlist *evlist, struct perf_cpu_map *cpus,
48 		  struct perf_thread_map *threads)
49 {
50 	int i;
51 
52 	for (i = 0; i < PERF_EVLIST__HLIST_SIZE; ++i)
53 		INIT_HLIST_HEAD(&evlist->heads[i]);
54 	perf_evlist__init(&evlist->core);
55 	perf_evlist__set_maps(&evlist->core, cpus, threads);
56 	fdarray__init(&evlist->pollfd, 64);
57 	evlist->workload.pid = -1;
58 	evlist->bkw_mmap_state = BKW_MMAP_NOTREADY;
59 }
60 
61 struct evlist *evlist__new(void)
62 {
63 	struct evlist *evlist = zalloc(sizeof(*evlist));
64 
65 	if (evlist != NULL)
66 		evlist__init(evlist, NULL, NULL);
67 
68 	return evlist;
69 }
70 
71 struct evlist *perf_evlist__new_default(void)
72 {
73 	struct evlist *evlist = evlist__new();
74 
75 	if (evlist && perf_evlist__add_default(evlist)) {
76 		evlist__delete(evlist);
77 		evlist = NULL;
78 	}
79 
80 	return evlist;
81 }
82 
83 struct evlist *perf_evlist__new_dummy(void)
84 {
85 	struct evlist *evlist = evlist__new();
86 
87 	if (evlist && perf_evlist__add_dummy(evlist)) {
88 		evlist__delete(evlist);
89 		evlist = NULL;
90 	}
91 
92 	return evlist;
93 }
94 
95 /**
96  * perf_evlist__set_id_pos - set the positions of event ids.
97  * @evlist: selected event list
98  *
99  * Events with compatible sample types all have the same id_pos
100  * and is_pos.  For convenience, put a copy on evlist.
101  */
102 void perf_evlist__set_id_pos(struct evlist *evlist)
103 {
104 	struct evsel *first = perf_evlist__first(evlist);
105 
106 	evlist->id_pos = first->id_pos;
107 	evlist->is_pos = first->is_pos;
108 }
109 
110 static void perf_evlist__update_id_pos(struct evlist *evlist)
111 {
112 	struct evsel *evsel;
113 
114 	evlist__for_each_entry(evlist, evsel)
115 		perf_evsel__calc_id_pos(evsel);
116 
117 	perf_evlist__set_id_pos(evlist);
118 }
119 
120 static void perf_evlist__purge(struct evlist *evlist)
121 {
122 	struct evsel *pos, *n;
123 
124 	evlist__for_each_entry_safe(evlist, n, pos) {
125 		list_del_init(&pos->core.node);
126 		pos->evlist = NULL;
127 		evsel__delete(pos);
128 	}
129 
130 	evlist->core.nr_entries = 0;
131 }
132 
133 void perf_evlist__exit(struct evlist *evlist)
134 {
135 	zfree(&evlist->mmap);
136 	zfree(&evlist->overwrite_mmap);
137 	fdarray__exit(&evlist->pollfd);
138 }
139 
140 void evlist__delete(struct evlist *evlist)
141 {
142 	if (evlist == NULL)
143 		return;
144 
145 	perf_evlist__munmap(evlist);
146 	evlist__close(evlist);
147 	perf_cpu_map__put(evlist->core.cpus);
148 	perf_thread_map__put(evlist->core.threads);
149 	evlist->core.cpus = NULL;
150 	evlist->core.threads = NULL;
151 	perf_evlist__purge(evlist);
152 	perf_evlist__exit(evlist);
153 	free(evlist);
154 }
155 
156 void evlist__add(struct evlist *evlist, struct evsel *entry)
157 {
158 	entry->evlist = evlist;
159 	entry->idx = evlist->core.nr_entries;
160 	entry->tracking = !entry->idx;
161 
162 	perf_evlist__add(&evlist->core, &entry->core);
163 
164 	if (evlist->core.nr_entries == 1)
165 		perf_evlist__set_id_pos(evlist);
166 }
167 
168 void evlist__remove(struct evlist *evlist, struct evsel *evsel)
169 {
170 	evsel->evlist = NULL;
171 	perf_evlist__remove(&evlist->core, &evsel->core);
172 }
173 
174 void perf_evlist__splice_list_tail(struct evlist *evlist,
175 				   struct list_head *list)
176 {
177 	struct evsel *evsel, *temp;
178 
179 	__evlist__for_each_entry_safe(list, temp, evsel) {
180 		list_del_init(&evsel->core.node);
181 		evlist__add(evlist, evsel);
182 	}
183 }
184 
185 void __perf_evlist__set_leader(struct list_head *list)
186 {
187 	struct evsel *evsel, *leader;
188 
189 	leader = list_entry(list->next, struct evsel, core.node);
190 	evsel = list_entry(list->prev, struct evsel, core.node);
191 
192 	leader->core.nr_members = evsel->idx - leader->idx + 1;
193 
194 	__evlist__for_each_entry(list, evsel) {
195 		evsel->leader = leader;
196 	}
197 }
198 
199 void perf_evlist__set_leader(struct evlist *evlist)
200 {
201 	if (evlist->core.nr_entries) {
202 		evlist->nr_groups = evlist->core.nr_entries > 1 ? 1 : 0;
203 		__perf_evlist__set_leader(&evlist->core.entries);
204 	}
205 }
206 
207 int __perf_evlist__add_default(struct evlist *evlist, bool precise)
208 {
209 	struct evsel *evsel = perf_evsel__new_cycles(precise);
210 
211 	if (evsel == NULL)
212 		return -ENOMEM;
213 
214 	evlist__add(evlist, evsel);
215 	return 0;
216 }
217 
218 int perf_evlist__add_dummy(struct evlist *evlist)
219 {
220 	struct perf_event_attr attr = {
221 		.type	= PERF_TYPE_SOFTWARE,
222 		.config = PERF_COUNT_SW_DUMMY,
223 		.size	= sizeof(attr), /* to capture ABI version */
224 	};
225 	struct evsel *evsel = perf_evsel__new_idx(&attr, evlist->core.nr_entries);
226 
227 	if (evsel == NULL)
228 		return -ENOMEM;
229 
230 	evlist__add(evlist, evsel);
231 	return 0;
232 }
233 
234 static int evlist__add_attrs(struct evlist *evlist,
235 				  struct perf_event_attr *attrs, size_t nr_attrs)
236 {
237 	struct evsel *evsel, *n;
238 	LIST_HEAD(head);
239 	size_t i;
240 
241 	for (i = 0; i < nr_attrs; i++) {
242 		evsel = perf_evsel__new_idx(attrs + i, evlist->core.nr_entries + i);
243 		if (evsel == NULL)
244 			goto out_delete_partial_list;
245 		list_add_tail(&evsel->core.node, &head);
246 	}
247 
248 	perf_evlist__splice_list_tail(evlist, &head);
249 
250 	return 0;
251 
252 out_delete_partial_list:
253 	__evlist__for_each_entry_safe(&head, n, evsel)
254 		evsel__delete(evsel);
255 	return -1;
256 }
257 
258 int __perf_evlist__add_default_attrs(struct evlist *evlist,
259 				     struct perf_event_attr *attrs, size_t nr_attrs)
260 {
261 	size_t i;
262 
263 	for (i = 0; i < nr_attrs; i++)
264 		event_attr_init(attrs + i);
265 
266 	return evlist__add_attrs(evlist, attrs, nr_attrs);
267 }
268 
269 struct evsel *
270 perf_evlist__find_tracepoint_by_id(struct evlist *evlist, int id)
271 {
272 	struct evsel *evsel;
273 
274 	evlist__for_each_entry(evlist, evsel) {
275 		if (evsel->core.attr.type   == PERF_TYPE_TRACEPOINT &&
276 		    (int)evsel->core.attr.config == id)
277 			return evsel;
278 	}
279 
280 	return NULL;
281 }
282 
283 struct evsel *
284 perf_evlist__find_tracepoint_by_name(struct evlist *evlist,
285 				     const char *name)
286 {
287 	struct evsel *evsel;
288 
289 	evlist__for_each_entry(evlist, evsel) {
290 		if ((evsel->core.attr.type == PERF_TYPE_TRACEPOINT) &&
291 		    (strcmp(evsel->name, name) == 0))
292 			return evsel;
293 	}
294 
295 	return NULL;
296 }
297 
298 int perf_evlist__add_newtp(struct evlist *evlist,
299 			   const char *sys, const char *name, void *handler)
300 {
301 	struct evsel *evsel = perf_evsel__newtp(sys, name);
302 
303 	if (IS_ERR(evsel))
304 		return -1;
305 
306 	evsel->handler = handler;
307 	evlist__add(evlist, evsel);
308 	return 0;
309 }
310 
311 static int perf_evlist__nr_threads(struct evlist *evlist,
312 				   struct evsel *evsel)
313 {
314 	if (evsel->system_wide)
315 		return 1;
316 	else
317 		return thread_map__nr(evlist->core.threads);
318 }
319 
320 void evlist__disable(struct evlist *evlist)
321 {
322 	struct evsel *pos;
323 
324 	evlist__for_each_entry(evlist, pos) {
325 		if (pos->disabled || !perf_evsel__is_group_leader(pos) || !pos->core.fd)
326 			continue;
327 		evsel__disable(pos);
328 	}
329 
330 	evlist->enabled = false;
331 }
332 
333 void evlist__enable(struct evlist *evlist)
334 {
335 	struct evsel *pos;
336 
337 	evlist__for_each_entry(evlist, pos) {
338 		if (!perf_evsel__is_group_leader(pos) || !pos->core.fd)
339 			continue;
340 		evsel__enable(pos);
341 	}
342 
343 	evlist->enabled = true;
344 }
345 
346 void perf_evlist__toggle_enable(struct evlist *evlist)
347 {
348 	(evlist->enabled ? evlist__disable : evlist__enable)(evlist);
349 }
350 
351 static int perf_evlist__enable_event_cpu(struct evlist *evlist,
352 					 struct evsel *evsel, int cpu)
353 {
354 	int thread;
355 	int nr_threads = perf_evlist__nr_threads(evlist, evsel);
356 
357 	if (!evsel->core.fd)
358 		return -EINVAL;
359 
360 	for (thread = 0; thread < nr_threads; thread++) {
361 		int err = ioctl(FD(evsel, cpu, thread), PERF_EVENT_IOC_ENABLE, 0);
362 		if (err)
363 			return err;
364 	}
365 	return 0;
366 }
367 
368 static int perf_evlist__enable_event_thread(struct evlist *evlist,
369 					    struct evsel *evsel,
370 					    int thread)
371 {
372 	int cpu;
373 	int nr_cpus = cpu_map__nr(evlist->core.cpus);
374 
375 	if (!evsel->core.fd)
376 		return -EINVAL;
377 
378 	for (cpu = 0; cpu < nr_cpus; cpu++) {
379 		int err = ioctl(FD(evsel, cpu, thread), PERF_EVENT_IOC_ENABLE, 0);
380 		if (err)
381 			return err;
382 	}
383 	return 0;
384 }
385 
386 int perf_evlist__enable_event_idx(struct evlist *evlist,
387 				  struct evsel *evsel, int idx)
388 {
389 	bool per_cpu_mmaps = !cpu_map__empty(evlist->core.cpus);
390 
391 	if (per_cpu_mmaps)
392 		return perf_evlist__enable_event_cpu(evlist, evsel, idx);
393 	else
394 		return perf_evlist__enable_event_thread(evlist, evsel, idx);
395 }
396 
397 int perf_evlist__alloc_pollfd(struct evlist *evlist)
398 {
399 	int nr_cpus = cpu_map__nr(evlist->core.cpus);
400 	int nr_threads = thread_map__nr(evlist->core.threads);
401 	int nfds = 0;
402 	struct evsel *evsel;
403 
404 	evlist__for_each_entry(evlist, evsel) {
405 		if (evsel->system_wide)
406 			nfds += nr_cpus;
407 		else
408 			nfds += nr_cpus * nr_threads;
409 	}
410 
411 	if (fdarray__available_entries(&evlist->pollfd) < nfds &&
412 	    fdarray__grow(&evlist->pollfd, nfds) < 0)
413 		return -ENOMEM;
414 
415 	return 0;
416 }
417 
418 static int __perf_evlist__add_pollfd(struct evlist *evlist, int fd,
419 				     struct perf_mmap *map, short revent)
420 {
421 	int pos = fdarray__add(&evlist->pollfd, fd, revent | POLLERR | POLLHUP);
422 	/*
423 	 * Save the idx so that when we filter out fds POLLHUP'ed we can
424 	 * close the associated evlist->mmap[] entry.
425 	 */
426 	if (pos >= 0) {
427 		evlist->pollfd.priv[pos].ptr = map;
428 
429 		fcntl(fd, F_SETFL, O_NONBLOCK);
430 	}
431 
432 	return pos;
433 }
434 
435 int perf_evlist__add_pollfd(struct evlist *evlist, int fd)
436 {
437 	return __perf_evlist__add_pollfd(evlist, fd, NULL, POLLIN);
438 }
439 
440 static void perf_evlist__munmap_filtered(struct fdarray *fda, int fd,
441 					 void *arg __maybe_unused)
442 {
443 	struct perf_mmap *map = fda->priv[fd].ptr;
444 
445 	if (map)
446 		perf_mmap__put(map);
447 }
448 
449 int perf_evlist__filter_pollfd(struct evlist *evlist, short revents_and_mask)
450 {
451 	return fdarray__filter(&evlist->pollfd, revents_and_mask,
452 			       perf_evlist__munmap_filtered, NULL);
453 }
454 
455 int perf_evlist__poll(struct evlist *evlist, int timeout)
456 {
457 	return fdarray__poll(&evlist->pollfd, timeout);
458 }
459 
460 static void perf_evlist__id_hash(struct evlist *evlist,
461 				 struct evsel *evsel,
462 				 int cpu, int thread, u64 id)
463 {
464 	int hash;
465 	struct perf_sample_id *sid = SID(evsel, cpu, thread);
466 
467 	sid->id = id;
468 	sid->evsel = evsel;
469 	hash = hash_64(sid->id, PERF_EVLIST__HLIST_BITS);
470 	hlist_add_head(&sid->node, &evlist->heads[hash]);
471 }
472 
473 void perf_evlist__id_add(struct evlist *evlist, struct evsel *evsel,
474 			 int cpu, int thread, u64 id)
475 {
476 	perf_evlist__id_hash(evlist, evsel, cpu, thread, id);
477 	evsel->id[evsel->ids++] = id;
478 }
479 
480 int perf_evlist__id_add_fd(struct evlist *evlist,
481 			   struct evsel *evsel,
482 			   int cpu, int thread, int fd)
483 {
484 	u64 read_data[4] = { 0, };
485 	int id_idx = 1; /* The first entry is the counter value */
486 	u64 id;
487 	int ret;
488 
489 	ret = ioctl(fd, PERF_EVENT_IOC_ID, &id);
490 	if (!ret)
491 		goto add;
492 
493 	if (errno != ENOTTY)
494 		return -1;
495 
496 	/* Legacy way to get event id.. All hail to old kernels! */
497 
498 	/*
499 	 * This way does not work with group format read, so bail
500 	 * out in that case.
501 	 */
502 	if (perf_evlist__read_format(evlist) & PERF_FORMAT_GROUP)
503 		return -1;
504 
505 	if (!(evsel->core.attr.read_format & PERF_FORMAT_ID) ||
506 	    read(fd, &read_data, sizeof(read_data)) == -1)
507 		return -1;
508 
509 	if (evsel->core.attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
510 		++id_idx;
511 	if (evsel->core.attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
512 		++id_idx;
513 
514 	id = read_data[id_idx];
515 
516  add:
517 	perf_evlist__id_add(evlist, evsel, cpu, thread, id);
518 	return 0;
519 }
520 
521 static void perf_evlist__set_sid_idx(struct evlist *evlist,
522 				     struct evsel *evsel, int idx, int cpu,
523 				     int thread)
524 {
525 	struct perf_sample_id *sid = SID(evsel, cpu, thread);
526 	sid->idx = idx;
527 	if (evlist->core.cpus && cpu >= 0)
528 		sid->cpu = evlist->core.cpus->map[cpu];
529 	else
530 		sid->cpu = -1;
531 	if (!evsel->system_wide && evlist->core.threads && thread >= 0)
532 		sid->tid = thread_map__pid(evlist->core.threads, thread);
533 	else
534 		sid->tid = -1;
535 }
536 
537 struct perf_sample_id *perf_evlist__id2sid(struct evlist *evlist, u64 id)
538 {
539 	struct hlist_head *head;
540 	struct perf_sample_id *sid;
541 	int hash;
542 
543 	hash = hash_64(id, PERF_EVLIST__HLIST_BITS);
544 	head = &evlist->heads[hash];
545 
546 	hlist_for_each_entry(sid, head, node)
547 		if (sid->id == id)
548 			return sid;
549 
550 	return NULL;
551 }
552 
553 struct evsel *perf_evlist__id2evsel(struct evlist *evlist, u64 id)
554 {
555 	struct perf_sample_id *sid;
556 
557 	if (evlist->core.nr_entries == 1 || !id)
558 		return perf_evlist__first(evlist);
559 
560 	sid = perf_evlist__id2sid(evlist, id);
561 	if (sid)
562 		return sid->evsel;
563 
564 	if (!perf_evlist__sample_id_all(evlist))
565 		return perf_evlist__first(evlist);
566 
567 	return NULL;
568 }
569 
570 struct evsel *perf_evlist__id2evsel_strict(struct evlist *evlist,
571 						u64 id)
572 {
573 	struct perf_sample_id *sid;
574 
575 	if (!id)
576 		return NULL;
577 
578 	sid = perf_evlist__id2sid(evlist, id);
579 	if (sid)
580 		return sid->evsel;
581 
582 	return NULL;
583 }
584 
585 static int perf_evlist__event2id(struct evlist *evlist,
586 				 union perf_event *event, u64 *id)
587 {
588 	const u64 *array = event->sample.array;
589 	ssize_t n;
590 
591 	n = (event->header.size - sizeof(event->header)) >> 3;
592 
593 	if (event->header.type == PERF_RECORD_SAMPLE) {
594 		if (evlist->id_pos >= n)
595 			return -1;
596 		*id = array[evlist->id_pos];
597 	} else {
598 		if (evlist->is_pos > n)
599 			return -1;
600 		n -= evlist->is_pos;
601 		*id = array[n];
602 	}
603 	return 0;
604 }
605 
606 struct evsel *perf_evlist__event2evsel(struct evlist *evlist,
607 					    union perf_event *event)
608 {
609 	struct evsel *first = perf_evlist__first(evlist);
610 	struct hlist_head *head;
611 	struct perf_sample_id *sid;
612 	int hash;
613 	u64 id;
614 
615 	if (evlist->core.nr_entries == 1)
616 		return first;
617 
618 	if (!first->core.attr.sample_id_all &&
619 	    event->header.type != PERF_RECORD_SAMPLE)
620 		return first;
621 
622 	if (perf_evlist__event2id(evlist, event, &id))
623 		return NULL;
624 
625 	/* Synthesized events have an id of zero */
626 	if (!id)
627 		return first;
628 
629 	hash = hash_64(id, PERF_EVLIST__HLIST_BITS);
630 	head = &evlist->heads[hash];
631 
632 	hlist_for_each_entry(sid, head, node) {
633 		if (sid->id == id)
634 			return sid->evsel;
635 	}
636 	return NULL;
637 }
638 
639 static int perf_evlist__set_paused(struct evlist *evlist, bool value)
640 {
641 	int i;
642 
643 	if (!evlist->overwrite_mmap)
644 		return 0;
645 
646 	for (i = 0; i < evlist->nr_mmaps; i++) {
647 		int fd = evlist->overwrite_mmap[i].fd;
648 		int err;
649 
650 		if (fd < 0)
651 			continue;
652 		err = ioctl(fd, PERF_EVENT_IOC_PAUSE_OUTPUT, value ? 1 : 0);
653 		if (err)
654 			return err;
655 	}
656 	return 0;
657 }
658 
659 static int perf_evlist__pause(struct evlist *evlist)
660 {
661 	return perf_evlist__set_paused(evlist, true);
662 }
663 
664 static int perf_evlist__resume(struct evlist *evlist)
665 {
666 	return perf_evlist__set_paused(evlist, false);
667 }
668 
669 static void perf_evlist__munmap_nofree(struct evlist *evlist)
670 {
671 	int i;
672 
673 	if (evlist->mmap)
674 		for (i = 0; i < evlist->nr_mmaps; i++)
675 			perf_mmap__munmap(&evlist->mmap[i]);
676 
677 	if (evlist->overwrite_mmap)
678 		for (i = 0; i < evlist->nr_mmaps; i++)
679 			perf_mmap__munmap(&evlist->overwrite_mmap[i]);
680 }
681 
682 void perf_evlist__munmap(struct evlist *evlist)
683 {
684 	perf_evlist__munmap_nofree(evlist);
685 	zfree(&evlist->mmap);
686 	zfree(&evlist->overwrite_mmap);
687 }
688 
689 static struct perf_mmap *perf_evlist__alloc_mmap(struct evlist *evlist,
690 						 bool overwrite)
691 {
692 	int i;
693 	struct perf_mmap *map;
694 
695 	evlist->nr_mmaps = cpu_map__nr(evlist->core.cpus);
696 	if (cpu_map__empty(evlist->core.cpus))
697 		evlist->nr_mmaps = thread_map__nr(evlist->core.threads);
698 	map = zalloc(evlist->nr_mmaps * sizeof(struct perf_mmap));
699 	if (!map)
700 		return NULL;
701 
702 	for (i = 0; i < evlist->nr_mmaps; i++) {
703 		map[i].fd = -1;
704 		map[i].overwrite = overwrite;
705 		/*
706 		 * When the perf_mmap() call is made we grab one refcount, plus
707 		 * one extra to let perf_mmap__consume() get the last
708 		 * events after all real references (perf_mmap__get()) are
709 		 * dropped.
710 		 *
711 		 * Each PERF_EVENT_IOC_SET_OUTPUT points to this mmap and
712 		 * thus does perf_mmap__get() on it.
713 		 */
714 		refcount_set(&map[i].refcnt, 0);
715 	}
716 	return map;
717 }
718 
719 static bool
720 perf_evlist__should_poll(struct evlist *evlist __maybe_unused,
721 			 struct evsel *evsel)
722 {
723 	if (evsel->core.attr.write_backward)
724 		return false;
725 	return true;
726 }
727 
728 static int perf_evlist__mmap_per_evsel(struct evlist *evlist, int idx,
729 				       struct mmap_params *mp, int cpu_idx,
730 				       int thread, int *_output, int *_output_overwrite)
731 {
732 	struct evsel *evsel;
733 	int revent;
734 	int evlist_cpu = cpu_map__cpu(evlist->core.cpus, cpu_idx);
735 
736 	evlist__for_each_entry(evlist, evsel) {
737 		struct perf_mmap *maps = evlist->mmap;
738 		int *output = _output;
739 		int fd;
740 		int cpu;
741 
742 		mp->prot = PROT_READ | PROT_WRITE;
743 		if (evsel->core.attr.write_backward) {
744 			output = _output_overwrite;
745 			maps = evlist->overwrite_mmap;
746 
747 			if (!maps) {
748 				maps = perf_evlist__alloc_mmap(evlist, true);
749 				if (!maps)
750 					return -1;
751 				evlist->overwrite_mmap = maps;
752 				if (evlist->bkw_mmap_state == BKW_MMAP_NOTREADY)
753 					perf_evlist__toggle_bkw_mmap(evlist, BKW_MMAP_RUNNING);
754 			}
755 			mp->prot &= ~PROT_WRITE;
756 		}
757 
758 		if (evsel->system_wide && thread)
759 			continue;
760 
761 		cpu = cpu_map__idx(evsel->core.cpus, evlist_cpu);
762 		if (cpu == -1)
763 			continue;
764 
765 		fd = FD(evsel, cpu, thread);
766 
767 		if (*output == -1) {
768 			*output = fd;
769 
770 			if (perf_mmap__mmap(&maps[idx], mp, *output, evlist_cpu) < 0)
771 				return -1;
772 		} else {
773 			if (ioctl(fd, PERF_EVENT_IOC_SET_OUTPUT, *output) != 0)
774 				return -1;
775 
776 			perf_mmap__get(&maps[idx]);
777 		}
778 
779 		revent = perf_evlist__should_poll(evlist, evsel) ? POLLIN : 0;
780 
781 		/*
782 		 * The system_wide flag causes a selected event to be opened
783 		 * always without a pid.  Consequently it will never get a
784 		 * POLLHUP, but it is used for tracking in combination with
785 		 * other events, so it should not need to be polled anyway.
786 		 * Therefore don't add it for polling.
787 		 */
788 		if (!evsel->system_wide &&
789 		    __perf_evlist__add_pollfd(evlist, fd, &maps[idx], revent) < 0) {
790 			perf_mmap__put(&maps[idx]);
791 			return -1;
792 		}
793 
794 		if (evsel->core.attr.read_format & PERF_FORMAT_ID) {
795 			if (perf_evlist__id_add_fd(evlist, evsel, cpu, thread,
796 						   fd) < 0)
797 				return -1;
798 			perf_evlist__set_sid_idx(evlist, evsel, idx, cpu,
799 						 thread);
800 		}
801 	}
802 
803 	return 0;
804 }
805 
806 static int perf_evlist__mmap_per_cpu(struct evlist *evlist,
807 				     struct mmap_params *mp)
808 {
809 	int cpu, thread;
810 	int nr_cpus = cpu_map__nr(evlist->core.cpus);
811 	int nr_threads = thread_map__nr(evlist->core.threads);
812 
813 	pr_debug2("perf event ring buffer mmapped per cpu\n");
814 	for (cpu = 0; cpu < nr_cpus; cpu++) {
815 		int output = -1;
816 		int output_overwrite = -1;
817 
818 		auxtrace_mmap_params__set_idx(&mp->auxtrace_mp, evlist, cpu,
819 					      true);
820 
821 		for (thread = 0; thread < nr_threads; thread++) {
822 			if (perf_evlist__mmap_per_evsel(evlist, cpu, mp, cpu,
823 							thread, &output, &output_overwrite))
824 				goto out_unmap;
825 		}
826 	}
827 
828 	return 0;
829 
830 out_unmap:
831 	perf_evlist__munmap_nofree(evlist);
832 	return -1;
833 }
834 
835 static int perf_evlist__mmap_per_thread(struct evlist *evlist,
836 					struct mmap_params *mp)
837 {
838 	int thread;
839 	int nr_threads = thread_map__nr(evlist->core.threads);
840 
841 	pr_debug2("perf event ring buffer mmapped per thread\n");
842 	for (thread = 0; thread < nr_threads; thread++) {
843 		int output = -1;
844 		int output_overwrite = -1;
845 
846 		auxtrace_mmap_params__set_idx(&mp->auxtrace_mp, evlist, thread,
847 					      false);
848 
849 		if (perf_evlist__mmap_per_evsel(evlist, thread, mp, 0, thread,
850 						&output, &output_overwrite))
851 			goto out_unmap;
852 	}
853 
854 	return 0;
855 
856 out_unmap:
857 	perf_evlist__munmap_nofree(evlist);
858 	return -1;
859 }
860 
861 unsigned long perf_event_mlock_kb_in_pages(void)
862 {
863 	unsigned long pages;
864 	int max;
865 
866 	if (sysctl__read_int("kernel/perf_event_mlock_kb", &max) < 0) {
867 		/*
868 		 * Pick a once upon a time good value, i.e. things look
869 		 * strange since we can't read a sysctl value, but lets not
870 		 * die yet...
871 		 */
872 		max = 512;
873 	} else {
874 		max -= (page_size / 1024);
875 	}
876 
877 	pages = (max * 1024) / page_size;
878 	if (!is_power_of_2(pages))
879 		pages = rounddown_pow_of_two(pages);
880 
881 	return pages;
882 }
883 
884 size_t perf_evlist__mmap_size(unsigned long pages)
885 {
886 	if (pages == UINT_MAX)
887 		pages = perf_event_mlock_kb_in_pages();
888 	else if (!is_power_of_2(pages))
889 		return 0;
890 
891 	return (pages + 1) * page_size;
892 }
893 
894 static long parse_pages_arg(const char *str, unsigned long min,
895 			    unsigned long max)
896 {
897 	unsigned long pages, val;
898 	static struct parse_tag tags[] = {
899 		{ .tag  = 'B', .mult = 1       },
900 		{ .tag  = 'K', .mult = 1 << 10 },
901 		{ .tag  = 'M', .mult = 1 << 20 },
902 		{ .tag  = 'G', .mult = 1 << 30 },
903 		{ .tag  = 0 },
904 	};
905 
906 	if (str == NULL)
907 		return -EINVAL;
908 
909 	val = parse_tag_value(str, tags);
910 	if (val != (unsigned long) -1) {
911 		/* we got file size value */
912 		pages = PERF_ALIGN(val, page_size) / page_size;
913 	} else {
914 		/* we got pages count value */
915 		char *eptr;
916 		pages = strtoul(str, &eptr, 10);
917 		if (*eptr != '\0')
918 			return -EINVAL;
919 	}
920 
921 	if (pages == 0 && min == 0) {
922 		/* leave number of pages at 0 */
923 	} else if (!is_power_of_2(pages)) {
924 		char buf[100];
925 
926 		/* round pages up to next power of 2 */
927 		pages = roundup_pow_of_two(pages);
928 		if (!pages)
929 			return -EINVAL;
930 
931 		unit_number__scnprintf(buf, sizeof(buf), pages * page_size);
932 		pr_info("rounding mmap pages size to %s (%lu pages)\n",
933 			buf, pages);
934 	}
935 
936 	if (pages > max)
937 		return -EINVAL;
938 
939 	return pages;
940 }
941 
942 int __perf_evlist__parse_mmap_pages(unsigned int *mmap_pages, const char *str)
943 {
944 	unsigned long max = UINT_MAX;
945 	long pages;
946 
947 	if (max > SIZE_MAX / page_size)
948 		max = SIZE_MAX / page_size;
949 
950 	pages = parse_pages_arg(str, 1, max);
951 	if (pages < 0) {
952 		pr_err("Invalid argument for --mmap_pages/-m\n");
953 		return -1;
954 	}
955 
956 	*mmap_pages = pages;
957 	return 0;
958 }
959 
960 int perf_evlist__parse_mmap_pages(const struct option *opt, const char *str,
961 				  int unset __maybe_unused)
962 {
963 	return __perf_evlist__parse_mmap_pages(opt->value, str);
964 }
965 
966 /**
967  * perf_evlist__mmap_ex - Create mmaps to receive events.
968  * @evlist: list of events
969  * @pages: map length in pages
970  * @overwrite: overwrite older events?
971  * @auxtrace_pages - auxtrace map length in pages
972  * @auxtrace_overwrite - overwrite older auxtrace data?
973  *
974  * If @overwrite is %false the user needs to signal event consumption using
975  * perf_mmap__write_tail().  Using perf_evlist__mmap_read() does this
976  * automatically.
977  *
978  * Similarly, if @auxtrace_overwrite is %false the user needs to signal data
979  * consumption using auxtrace_mmap__write_tail().
980  *
981  * Return: %0 on success, negative error code otherwise.
982  */
983 int perf_evlist__mmap_ex(struct evlist *evlist, unsigned int pages,
984 			 unsigned int auxtrace_pages,
985 			 bool auxtrace_overwrite, int nr_cblocks, int affinity, int flush,
986 			 int comp_level)
987 {
988 	struct evsel *evsel;
989 	const struct perf_cpu_map *cpus = evlist->core.cpus;
990 	const struct perf_thread_map *threads = evlist->core.threads;
991 	/*
992 	 * Delay setting mp.prot: set it before calling perf_mmap__mmap.
993 	 * Its value is decided by evsel's write_backward.
994 	 * So &mp should not be passed through const pointer.
995 	 */
996 	struct mmap_params mp = { .nr_cblocks = nr_cblocks, .affinity = affinity, .flush = flush,
997 				  .comp_level = comp_level };
998 
999 	if (!evlist->mmap)
1000 		evlist->mmap = perf_evlist__alloc_mmap(evlist, false);
1001 	if (!evlist->mmap)
1002 		return -ENOMEM;
1003 
1004 	if (evlist->pollfd.entries == NULL && perf_evlist__alloc_pollfd(evlist) < 0)
1005 		return -ENOMEM;
1006 
1007 	evlist->mmap_len = perf_evlist__mmap_size(pages);
1008 	pr_debug("mmap size %zuB\n", evlist->mmap_len);
1009 	mp.mask = evlist->mmap_len - page_size - 1;
1010 
1011 	auxtrace_mmap_params__init(&mp.auxtrace_mp, evlist->mmap_len,
1012 				   auxtrace_pages, auxtrace_overwrite);
1013 
1014 	evlist__for_each_entry(evlist, evsel) {
1015 		if ((evsel->core.attr.read_format & PERF_FORMAT_ID) &&
1016 		    evsel->sample_id == NULL &&
1017 		    perf_evsel__alloc_id(evsel, cpu_map__nr(cpus), threads->nr) < 0)
1018 			return -ENOMEM;
1019 	}
1020 
1021 	if (cpu_map__empty(cpus))
1022 		return perf_evlist__mmap_per_thread(evlist, &mp);
1023 
1024 	return perf_evlist__mmap_per_cpu(evlist, &mp);
1025 }
1026 
1027 int perf_evlist__mmap(struct evlist *evlist, unsigned int pages)
1028 {
1029 	return perf_evlist__mmap_ex(evlist, pages, 0, false, 0, PERF_AFFINITY_SYS, 1, 0);
1030 }
1031 
1032 int perf_evlist__create_maps(struct evlist *evlist, struct target *target)
1033 {
1034 	bool all_threads = (target->per_thread && target->system_wide);
1035 	struct perf_cpu_map *cpus;
1036 	struct perf_thread_map *threads;
1037 
1038 	/*
1039 	 * If specify '-a' and '--per-thread' to perf record, perf record
1040 	 * will override '--per-thread'. target->per_thread = false and
1041 	 * target->system_wide = true.
1042 	 *
1043 	 * If specify '--per-thread' only to perf record,
1044 	 * target->per_thread = true and target->system_wide = false.
1045 	 *
1046 	 * So target->per_thread && target->system_wide is false.
1047 	 * For perf record, thread_map__new_str doesn't call
1048 	 * thread_map__new_all_cpus. That will keep perf record's
1049 	 * current behavior.
1050 	 *
1051 	 * For perf stat, it allows the case that target->per_thread and
1052 	 * target->system_wide are all true. It means to collect system-wide
1053 	 * per-thread data. thread_map__new_str will call
1054 	 * thread_map__new_all_cpus to enumerate all threads.
1055 	 */
1056 	threads = thread_map__new_str(target->pid, target->tid, target->uid,
1057 				      all_threads);
1058 
1059 	if (!threads)
1060 		return -1;
1061 
1062 	if (target__uses_dummy_map(target))
1063 		cpus = perf_cpu_map__dummy_new();
1064 	else
1065 		cpus = perf_cpu_map__new(target->cpu_list);
1066 
1067 	if (!cpus)
1068 		goto out_delete_threads;
1069 
1070 	evlist->core.has_user_cpus = !!target->cpu_list;
1071 
1072 	perf_evlist__set_maps(&evlist->core, cpus, threads);
1073 
1074 	return 0;
1075 
1076 out_delete_threads:
1077 	perf_thread_map__put(threads);
1078 	return -1;
1079 }
1080 
1081 void __perf_evlist__set_sample_bit(struct evlist *evlist,
1082 				   enum perf_event_sample_format bit)
1083 {
1084 	struct evsel *evsel;
1085 
1086 	evlist__for_each_entry(evlist, evsel)
1087 		__perf_evsel__set_sample_bit(evsel, bit);
1088 }
1089 
1090 void __perf_evlist__reset_sample_bit(struct evlist *evlist,
1091 				     enum perf_event_sample_format bit)
1092 {
1093 	struct evsel *evsel;
1094 
1095 	evlist__for_each_entry(evlist, evsel)
1096 		__perf_evsel__reset_sample_bit(evsel, bit);
1097 }
1098 
1099 int perf_evlist__apply_filters(struct evlist *evlist, struct evsel **err_evsel)
1100 {
1101 	struct evsel *evsel;
1102 	int err = 0;
1103 
1104 	evlist__for_each_entry(evlist, evsel) {
1105 		if (evsel->filter == NULL)
1106 			continue;
1107 
1108 		/*
1109 		 * filters only work for tracepoint event, which doesn't have cpu limit.
1110 		 * So evlist and evsel should always be same.
1111 		 */
1112 		err = perf_evsel__apply_filter(&evsel->core, evsel->filter);
1113 		if (err) {
1114 			*err_evsel = evsel;
1115 			break;
1116 		}
1117 	}
1118 
1119 	return err;
1120 }
1121 
1122 int perf_evlist__set_tp_filter(struct evlist *evlist, const char *filter)
1123 {
1124 	struct evsel *evsel;
1125 	int err = 0;
1126 
1127 	evlist__for_each_entry(evlist, evsel) {
1128 		if (evsel->core.attr.type != PERF_TYPE_TRACEPOINT)
1129 			continue;
1130 
1131 		err = perf_evsel__set_filter(evsel, filter);
1132 		if (err)
1133 			break;
1134 	}
1135 
1136 	return err;
1137 }
1138 
1139 int perf_evlist__set_tp_filter_pids(struct evlist *evlist, size_t npids, pid_t *pids)
1140 {
1141 	char *filter;
1142 	int ret = -1;
1143 	size_t i;
1144 
1145 	for (i = 0; i < npids; ++i) {
1146 		if (i == 0) {
1147 			if (asprintf(&filter, "common_pid != %d", pids[i]) < 0)
1148 				return -1;
1149 		} else {
1150 			char *tmp;
1151 
1152 			if (asprintf(&tmp, "%s && common_pid != %d", filter, pids[i]) < 0)
1153 				goto out_free;
1154 
1155 			free(filter);
1156 			filter = tmp;
1157 		}
1158 	}
1159 
1160 	ret = perf_evlist__set_tp_filter(evlist, filter);
1161 out_free:
1162 	free(filter);
1163 	return ret;
1164 }
1165 
1166 int perf_evlist__set_tp_filter_pid(struct evlist *evlist, pid_t pid)
1167 {
1168 	return perf_evlist__set_tp_filter_pids(evlist, 1, &pid);
1169 }
1170 
1171 bool perf_evlist__valid_sample_type(struct evlist *evlist)
1172 {
1173 	struct evsel *pos;
1174 
1175 	if (evlist->core.nr_entries == 1)
1176 		return true;
1177 
1178 	if (evlist->id_pos < 0 || evlist->is_pos < 0)
1179 		return false;
1180 
1181 	evlist__for_each_entry(evlist, pos) {
1182 		if (pos->id_pos != evlist->id_pos ||
1183 		    pos->is_pos != evlist->is_pos)
1184 			return false;
1185 	}
1186 
1187 	return true;
1188 }
1189 
1190 u64 __perf_evlist__combined_sample_type(struct evlist *evlist)
1191 {
1192 	struct evsel *evsel;
1193 
1194 	if (evlist->combined_sample_type)
1195 		return evlist->combined_sample_type;
1196 
1197 	evlist__for_each_entry(evlist, evsel)
1198 		evlist->combined_sample_type |= evsel->core.attr.sample_type;
1199 
1200 	return evlist->combined_sample_type;
1201 }
1202 
1203 u64 perf_evlist__combined_sample_type(struct evlist *evlist)
1204 {
1205 	evlist->combined_sample_type = 0;
1206 	return __perf_evlist__combined_sample_type(evlist);
1207 }
1208 
1209 u64 perf_evlist__combined_branch_type(struct evlist *evlist)
1210 {
1211 	struct evsel *evsel;
1212 	u64 branch_type = 0;
1213 
1214 	evlist__for_each_entry(evlist, evsel)
1215 		branch_type |= evsel->core.attr.branch_sample_type;
1216 	return branch_type;
1217 }
1218 
1219 bool perf_evlist__valid_read_format(struct evlist *evlist)
1220 {
1221 	struct evsel *first = perf_evlist__first(evlist), *pos = first;
1222 	u64 read_format = first->core.attr.read_format;
1223 	u64 sample_type = first->core.attr.sample_type;
1224 
1225 	evlist__for_each_entry(evlist, pos) {
1226 		if (read_format != pos->core.attr.read_format)
1227 			return false;
1228 	}
1229 
1230 	/* PERF_SAMPLE_READ imples PERF_FORMAT_ID. */
1231 	if ((sample_type & PERF_SAMPLE_READ) &&
1232 	    !(read_format & PERF_FORMAT_ID)) {
1233 		return false;
1234 	}
1235 
1236 	return true;
1237 }
1238 
1239 u64 perf_evlist__read_format(struct evlist *evlist)
1240 {
1241 	struct evsel *first = perf_evlist__first(evlist);
1242 	return first->core.attr.read_format;
1243 }
1244 
1245 u16 perf_evlist__id_hdr_size(struct evlist *evlist)
1246 {
1247 	struct evsel *first = perf_evlist__first(evlist);
1248 	struct perf_sample *data;
1249 	u64 sample_type;
1250 	u16 size = 0;
1251 
1252 	if (!first->core.attr.sample_id_all)
1253 		goto out;
1254 
1255 	sample_type = first->core.attr.sample_type;
1256 
1257 	if (sample_type & PERF_SAMPLE_TID)
1258 		size += sizeof(data->tid) * 2;
1259 
1260        if (sample_type & PERF_SAMPLE_TIME)
1261 		size += sizeof(data->time);
1262 
1263 	if (sample_type & PERF_SAMPLE_ID)
1264 		size += sizeof(data->id);
1265 
1266 	if (sample_type & PERF_SAMPLE_STREAM_ID)
1267 		size += sizeof(data->stream_id);
1268 
1269 	if (sample_type & PERF_SAMPLE_CPU)
1270 		size += sizeof(data->cpu) * 2;
1271 
1272 	if (sample_type & PERF_SAMPLE_IDENTIFIER)
1273 		size += sizeof(data->id);
1274 out:
1275 	return size;
1276 }
1277 
1278 bool perf_evlist__valid_sample_id_all(struct evlist *evlist)
1279 {
1280 	struct evsel *first = perf_evlist__first(evlist), *pos = first;
1281 
1282 	evlist__for_each_entry_continue(evlist, pos) {
1283 		if (first->core.attr.sample_id_all != pos->core.attr.sample_id_all)
1284 			return false;
1285 	}
1286 
1287 	return true;
1288 }
1289 
1290 bool perf_evlist__sample_id_all(struct evlist *evlist)
1291 {
1292 	struct evsel *first = perf_evlist__first(evlist);
1293 	return first->core.attr.sample_id_all;
1294 }
1295 
1296 void perf_evlist__set_selected(struct evlist *evlist,
1297 			       struct evsel *evsel)
1298 {
1299 	evlist->selected = evsel;
1300 }
1301 
1302 void evlist__close(struct evlist *evlist)
1303 {
1304 	struct evsel *evsel;
1305 
1306 	evlist__for_each_entry_reverse(evlist, evsel)
1307 		evsel__close(evsel);
1308 }
1309 
1310 static int perf_evlist__create_syswide_maps(struct evlist *evlist)
1311 {
1312 	struct perf_cpu_map *cpus;
1313 	struct perf_thread_map *threads;
1314 	int err = -ENOMEM;
1315 
1316 	/*
1317 	 * Try reading /sys/devices/system/cpu/online to get
1318 	 * an all cpus map.
1319 	 *
1320 	 * FIXME: -ENOMEM is the best we can do here, the cpu_map
1321 	 * code needs an overhaul to properly forward the
1322 	 * error, and we may not want to do that fallback to a
1323 	 * default cpu identity map :-\
1324 	 */
1325 	cpus = perf_cpu_map__new(NULL);
1326 	if (!cpus)
1327 		goto out;
1328 
1329 	threads = perf_thread_map__new_dummy();
1330 	if (!threads)
1331 		goto out_put;
1332 
1333 	perf_evlist__set_maps(&evlist->core, cpus, threads);
1334 out:
1335 	return err;
1336 out_put:
1337 	perf_cpu_map__put(cpus);
1338 	goto out;
1339 }
1340 
1341 int evlist__open(struct evlist *evlist)
1342 {
1343 	struct evsel *evsel;
1344 	int err;
1345 
1346 	/*
1347 	 * Default: one fd per CPU, all threads, aka systemwide
1348 	 * as sys_perf_event_open(cpu = -1, thread = -1) is EINVAL
1349 	 */
1350 	if (evlist->core.threads == NULL && evlist->core.cpus == NULL) {
1351 		err = perf_evlist__create_syswide_maps(evlist);
1352 		if (err < 0)
1353 			goto out_err;
1354 	}
1355 
1356 	perf_evlist__update_id_pos(evlist);
1357 
1358 	evlist__for_each_entry(evlist, evsel) {
1359 		err = evsel__open(evsel, evsel->core.cpus, evsel->core.threads);
1360 		if (err < 0)
1361 			goto out_err;
1362 	}
1363 
1364 	return 0;
1365 out_err:
1366 	evlist__close(evlist);
1367 	errno = -err;
1368 	return err;
1369 }
1370 
1371 int perf_evlist__prepare_workload(struct evlist *evlist, struct target *target,
1372 				  const char *argv[], bool pipe_output,
1373 				  void (*exec_error)(int signo, siginfo_t *info, void *ucontext))
1374 {
1375 	int child_ready_pipe[2], go_pipe[2];
1376 	char bf;
1377 
1378 	if (pipe(child_ready_pipe) < 0) {
1379 		perror("failed to create 'ready' pipe");
1380 		return -1;
1381 	}
1382 
1383 	if (pipe(go_pipe) < 0) {
1384 		perror("failed to create 'go' pipe");
1385 		goto out_close_ready_pipe;
1386 	}
1387 
1388 	evlist->workload.pid = fork();
1389 	if (evlist->workload.pid < 0) {
1390 		perror("failed to fork");
1391 		goto out_close_pipes;
1392 	}
1393 
1394 	if (!evlist->workload.pid) {
1395 		int ret;
1396 
1397 		if (pipe_output)
1398 			dup2(2, 1);
1399 
1400 		signal(SIGTERM, SIG_DFL);
1401 
1402 		close(child_ready_pipe[0]);
1403 		close(go_pipe[1]);
1404 		fcntl(go_pipe[0], F_SETFD, FD_CLOEXEC);
1405 
1406 		/*
1407 		 * Tell the parent we're ready to go
1408 		 */
1409 		close(child_ready_pipe[1]);
1410 
1411 		/*
1412 		 * Wait until the parent tells us to go.
1413 		 */
1414 		ret = read(go_pipe[0], &bf, 1);
1415 		/*
1416 		 * The parent will ask for the execvp() to be performed by
1417 		 * writing exactly one byte, in workload.cork_fd, usually via
1418 		 * perf_evlist__start_workload().
1419 		 *
1420 		 * For cancelling the workload without actually running it,
1421 		 * the parent will just close workload.cork_fd, without writing
1422 		 * anything, i.e. read will return zero and we just exit()
1423 		 * here.
1424 		 */
1425 		if (ret != 1) {
1426 			if (ret == -1)
1427 				perror("unable to read pipe");
1428 			exit(ret);
1429 		}
1430 
1431 		execvp(argv[0], (char **)argv);
1432 
1433 		if (exec_error) {
1434 			union sigval val;
1435 
1436 			val.sival_int = errno;
1437 			if (sigqueue(getppid(), SIGUSR1, val))
1438 				perror(argv[0]);
1439 		} else
1440 			perror(argv[0]);
1441 		exit(-1);
1442 	}
1443 
1444 	if (exec_error) {
1445 		struct sigaction act = {
1446 			.sa_flags     = SA_SIGINFO,
1447 			.sa_sigaction = exec_error,
1448 		};
1449 		sigaction(SIGUSR1, &act, NULL);
1450 	}
1451 
1452 	if (target__none(target)) {
1453 		if (evlist->core.threads == NULL) {
1454 			fprintf(stderr, "FATAL: evlist->threads need to be set at this point (%s:%d).\n",
1455 				__func__, __LINE__);
1456 			goto out_close_pipes;
1457 		}
1458 		perf_thread_map__set_pid(evlist->core.threads, 0, evlist->workload.pid);
1459 	}
1460 
1461 	close(child_ready_pipe[1]);
1462 	close(go_pipe[0]);
1463 	/*
1464 	 * wait for child to settle
1465 	 */
1466 	if (read(child_ready_pipe[0], &bf, 1) == -1) {
1467 		perror("unable to read pipe");
1468 		goto out_close_pipes;
1469 	}
1470 
1471 	fcntl(go_pipe[1], F_SETFD, FD_CLOEXEC);
1472 	evlist->workload.cork_fd = go_pipe[1];
1473 	close(child_ready_pipe[0]);
1474 	return 0;
1475 
1476 out_close_pipes:
1477 	close(go_pipe[0]);
1478 	close(go_pipe[1]);
1479 out_close_ready_pipe:
1480 	close(child_ready_pipe[0]);
1481 	close(child_ready_pipe[1]);
1482 	return -1;
1483 }
1484 
1485 int perf_evlist__start_workload(struct evlist *evlist)
1486 {
1487 	if (evlist->workload.cork_fd > 0) {
1488 		char bf = 0;
1489 		int ret;
1490 		/*
1491 		 * Remove the cork, let it rip!
1492 		 */
1493 		ret = write(evlist->workload.cork_fd, &bf, 1);
1494 		if (ret < 0)
1495 			perror("unable to write to pipe");
1496 
1497 		close(evlist->workload.cork_fd);
1498 		return ret;
1499 	}
1500 
1501 	return 0;
1502 }
1503 
1504 int perf_evlist__parse_sample(struct evlist *evlist, union perf_event *event,
1505 			      struct perf_sample *sample)
1506 {
1507 	struct evsel *evsel = perf_evlist__event2evsel(evlist, event);
1508 
1509 	if (!evsel)
1510 		return -EFAULT;
1511 	return perf_evsel__parse_sample(evsel, event, sample);
1512 }
1513 
1514 int perf_evlist__parse_sample_timestamp(struct evlist *evlist,
1515 					union perf_event *event,
1516 					u64 *timestamp)
1517 {
1518 	struct evsel *evsel = perf_evlist__event2evsel(evlist, event);
1519 
1520 	if (!evsel)
1521 		return -EFAULT;
1522 	return perf_evsel__parse_sample_timestamp(evsel, event, timestamp);
1523 }
1524 
1525 size_t perf_evlist__fprintf(struct evlist *evlist, FILE *fp)
1526 {
1527 	struct evsel *evsel;
1528 	size_t printed = 0;
1529 
1530 	evlist__for_each_entry(evlist, evsel) {
1531 		printed += fprintf(fp, "%s%s", evsel->idx ? ", " : "",
1532 				   perf_evsel__name(evsel));
1533 	}
1534 
1535 	return printed + fprintf(fp, "\n");
1536 }
1537 
1538 int perf_evlist__strerror_open(struct evlist *evlist,
1539 			       int err, char *buf, size_t size)
1540 {
1541 	int printed, value;
1542 	char sbuf[STRERR_BUFSIZE], *emsg = str_error_r(err, sbuf, sizeof(sbuf));
1543 
1544 	switch (err) {
1545 	case EACCES:
1546 	case EPERM:
1547 		printed = scnprintf(buf, size,
1548 				    "Error:\t%s.\n"
1549 				    "Hint:\tCheck /proc/sys/kernel/perf_event_paranoid setting.", emsg);
1550 
1551 		value = perf_event_paranoid();
1552 
1553 		printed += scnprintf(buf + printed, size - printed, "\nHint:\t");
1554 
1555 		if (value >= 2) {
1556 			printed += scnprintf(buf + printed, size - printed,
1557 					     "For your workloads it needs to be <= 1\nHint:\t");
1558 		}
1559 		printed += scnprintf(buf + printed, size - printed,
1560 				     "For system wide tracing it needs to be set to -1.\n");
1561 
1562 		printed += scnprintf(buf + printed, size - printed,
1563 				    "Hint:\tTry: 'sudo sh -c \"echo -1 > /proc/sys/kernel/perf_event_paranoid\"'\n"
1564 				    "Hint:\tThe current value is %d.", value);
1565 		break;
1566 	case EINVAL: {
1567 		struct evsel *first = perf_evlist__first(evlist);
1568 		int max_freq;
1569 
1570 		if (sysctl__read_int("kernel/perf_event_max_sample_rate", &max_freq) < 0)
1571 			goto out_default;
1572 
1573 		if (first->core.attr.sample_freq < (u64)max_freq)
1574 			goto out_default;
1575 
1576 		printed = scnprintf(buf, size,
1577 				    "Error:\t%s.\n"
1578 				    "Hint:\tCheck /proc/sys/kernel/perf_event_max_sample_rate.\n"
1579 				    "Hint:\tThe current value is %d and %" PRIu64 " is being requested.",
1580 				    emsg, max_freq, first->core.attr.sample_freq);
1581 		break;
1582 	}
1583 	default:
1584 out_default:
1585 		scnprintf(buf, size, "%s", emsg);
1586 		break;
1587 	}
1588 
1589 	return 0;
1590 }
1591 
1592 int perf_evlist__strerror_mmap(struct evlist *evlist, int err, char *buf, size_t size)
1593 {
1594 	char sbuf[STRERR_BUFSIZE], *emsg = str_error_r(err, sbuf, sizeof(sbuf));
1595 	int pages_attempted = evlist->mmap_len / 1024, pages_max_per_user, printed = 0;
1596 
1597 	switch (err) {
1598 	case EPERM:
1599 		sysctl__read_int("kernel/perf_event_mlock_kb", &pages_max_per_user);
1600 		printed += scnprintf(buf + printed, size - printed,
1601 				     "Error:\t%s.\n"
1602 				     "Hint:\tCheck /proc/sys/kernel/perf_event_mlock_kb (%d kB) setting.\n"
1603 				     "Hint:\tTried using %zd kB.\n",
1604 				     emsg, pages_max_per_user, pages_attempted);
1605 
1606 		if (pages_attempted >= pages_max_per_user) {
1607 			printed += scnprintf(buf + printed, size - printed,
1608 					     "Hint:\tTry 'sudo sh -c \"echo %d > /proc/sys/kernel/perf_event_mlock_kb\"', or\n",
1609 					     pages_max_per_user + pages_attempted);
1610 		}
1611 
1612 		printed += scnprintf(buf + printed, size - printed,
1613 				     "Hint:\tTry using a smaller -m/--mmap-pages value.");
1614 		break;
1615 	default:
1616 		scnprintf(buf, size, "%s", emsg);
1617 		break;
1618 	}
1619 
1620 	return 0;
1621 }
1622 
1623 void perf_evlist__to_front(struct evlist *evlist,
1624 			   struct evsel *move_evsel)
1625 {
1626 	struct evsel *evsel, *n;
1627 	LIST_HEAD(move);
1628 
1629 	if (move_evsel == perf_evlist__first(evlist))
1630 		return;
1631 
1632 	evlist__for_each_entry_safe(evlist, n, evsel) {
1633 		if (evsel->leader == move_evsel->leader)
1634 			list_move_tail(&evsel->core.node, &move);
1635 	}
1636 
1637 	list_splice(&move, &evlist->core.entries);
1638 }
1639 
1640 void perf_evlist__set_tracking_event(struct evlist *evlist,
1641 				     struct evsel *tracking_evsel)
1642 {
1643 	struct evsel *evsel;
1644 
1645 	if (tracking_evsel->tracking)
1646 		return;
1647 
1648 	evlist__for_each_entry(evlist, evsel) {
1649 		if (evsel != tracking_evsel)
1650 			evsel->tracking = false;
1651 	}
1652 
1653 	tracking_evsel->tracking = true;
1654 }
1655 
1656 struct evsel *
1657 perf_evlist__find_evsel_by_str(struct evlist *evlist,
1658 			       const char *str)
1659 {
1660 	struct evsel *evsel;
1661 
1662 	evlist__for_each_entry(evlist, evsel) {
1663 		if (!evsel->name)
1664 			continue;
1665 		if (strcmp(str, evsel->name) == 0)
1666 			return evsel;
1667 	}
1668 
1669 	return NULL;
1670 }
1671 
1672 void perf_evlist__toggle_bkw_mmap(struct evlist *evlist,
1673 				  enum bkw_mmap_state state)
1674 {
1675 	enum bkw_mmap_state old_state = evlist->bkw_mmap_state;
1676 	enum action {
1677 		NONE,
1678 		PAUSE,
1679 		RESUME,
1680 	} action = NONE;
1681 
1682 	if (!evlist->overwrite_mmap)
1683 		return;
1684 
1685 	switch (old_state) {
1686 	case BKW_MMAP_NOTREADY: {
1687 		if (state != BKW_MMAP_RUNNING)
1688 			goto state_err;
1689 		break;
1690 	}
1691 	case BKW_MMAP_RUNNING: {
1692 		if (state != BKW_MMAP_DATA_PENDING)
1693 			goto state_err;
1694 		action = PAUSE;
1695 		break;
1696 	}
1697 	case BKW_MMAP_DATA_PENDING: {
1698 		if (state != BKW_MMAP_EMPTY)
1699 			goto state_err;
1700 		break;
1701 	}
1702 	case BKW_MMAP_EMPTY: {
1703 		if (state != BKW_MMAP_RUNNING)
1704 			goto state_err;
1705 		action = RESUME;
1706 		break;
1707 	}
1708 	default:
1709 		WARN_ONCE(1, "Shouldn't get there\n");
1710 	}
1711 
1712 	evlist->bkw_mmap_state = state;
1713 
1714 	switch (action) {
1715 	case PAUSE:
1716 		perf_evlist__pause(evlist);
1717 		break;
1718 	case RESUME:
1719 		perf_evlist__resume(evlist);
1720 		break;
1721 	case NONE:
1722 	default:
1723 		break;
1724 	}
1725 
1726 state_err:
1727 	return;
1728 }
1729 
1730 bool perf_evlist__exclude_kernel(struct evlist *evlist)
1731 {
1732 	struct evsel *evsel;
1733 
1734 	evlist__for_each_entry(evlist, evsel) {
1735 		if (!evsel->core.attr.exclude_kernel)
1736 			return false;
1737 	}
1738 
1739 	return true;
1740 }
1741 
1742 /*
1743  * Events in data file are not collect in groups, but we still want
1744  * the group display. Set the artificial group and set the leader's
1745  * forced_leader flag to notify the display code.
1746  */
1747 void perf_evlist__force_leader(struct evlist *evlist)
1748 {
1749 	if (!evlist->nr_groups) {
1750 		struct evsel *leader = perf_evlist__first(evlist);
1751 
1752 		perf_evlist__set_leader(evlist);
1753 		leader->forced_leader = true;
1754 	}
1755 }
1756 
1757 struct evsel *perf_evlist__reset_weak_group(struct evlist *evsel_list,
1758 						 struct evsel *evsel)
1759 {
1760 	struct evsel *c2, *leader;
1761 	bool is_open = true;
1762 
1763 	leader = evsel->leader;
1764 	pr_debug("Weak group for %s/%d failed\n",
1765 			leader->name, leader->core.nr_members);
1766 
1767 	/*
1768 	 * for_each_group_member doesn't work here because it doesn't
1769 	 * include the first entry.
1770 	 */
1771 	evlist__for_each_entry(evsel_list, c2) {
1772 		if (c2 == evsel)
1773 			is_open = false;
1774 		if (c2->leader == leader) {
1775 			if (is_open)
1776 				evsel__close(c2);
1777 			c2->leader = c2;
1778 			c2->core.nr_members = 0;
1779 		}
1780 	}
1781 	return leader;
1782 }
1783 
1784 int perf_evlist__add_sb_event(struct evlist **evlist,
1785 			      struct perf_event_attr *attr,
1786 			      perf_evsel__sb_cb_t cb,
1787 			      void *data)
1788 {
1789 	struct evsel *evsel;
1790 	bool new_evlist = (*evlist) == NULL;
1791 
1792 	if (*evlist == NULL)
1793 		*evlist = evlist__new();
1794 	if (*evlist == NULL)
1795 		return -1;
1796 
1797 	if (!attr->sample_id_all) {
1798 		pr_warning("enabling sample_id_all for all side band events\n");
1799 		attr->sample_id_all = 1;
1800 	}
1801 
1802 	evsel = perf_evsel__new_idx(attr, (*evlist)->core.nr_entries);
1803 	if (!evsel)
1804 		goto out_err;
1805 
1806 	evsel->side_band.cb = cb;
1807 	evsel->side_band.data = data;
1808 	evlist__add(*evlist, evsel);
1809 	return 0;
1810 
1811 out_err:
1812 	if (new_evlist) {
1813 		evlist__delete(*evlist);
1814 		*evlist = NULL;
1815 	}
1816 	return -1;
1817 }
1818 
1819 static void *perf_evlist__poll_thread(void *arg)
1820 {
1821 	struct evlist *evlist = arg;
1822 	bool draining = false;
1823 	int i, done = 0;
1824 
1825 	while (!done) {
1826 		bool got_data = false;
1827 
1828 		if (evlist->thread.done)
1829 			draining = true;
1830 
1831 		if (!draining)
1832 			perf_evlist__poll(evlist, 1000);
1833 
1834 		for (i = 0; i < evlist->nr_mmaps; i++) {
1835 			struct perf_mmap *map = &evlist->mmap[i];
1836 			union perf_event *event;
1837 
1838 			if (perf_mmap__read_init(map))
1839 				continue;
1840 			while ((event = perf_mmap__read_event(map)) != NULL) {
1841 				struct evsel *evsel = perf_evlist__event2evsel(evlist, event);
1842 
1843 				if (evsel && evsel->side_band.cb)
1844 					evsel->side_band.cb(event, evsel->side_band.data);
1845 				else
1846 					pr_warning("cannot locate proper evsel for the side band event\n");
1847 
1848 				perf_mmap__consume(map);
1849 				got_data = true;
1850 			}
1851 			perf_mmap__read_done(map);
1852 		}
1853 
1854 		if (draining && !got_data)
1855 			break;
1856 	}
1857 	return NULL;
1858 }
1859 
1860 int perf_evlist__start_sb_thread(struct evlist *evlist,
1861 				 struct target *target)
1862 {
1863 	struct evsel *counter;
1864 
1865 	if (!evlist)
1866 		return 0;
1867 
1868 	if (perf_evlist__create_maps(evlist, target))
1869 		goto out_delete_evlist;
1870 
1871 	evlist__for_each_entry(evlist, counter) {
1872 		if (evsel__open(counter, evlist->core.cpus,
1873 				     evlist->core.threads) < 0)
1874 			goto out_delete_evlist;
1875 	}
1876 
1877 	if (perf_evlist__mmap(evlist, UINT_MAX))
1878 		goto out_delete_evlist;
1879 
1880 	evlist__for_each_entry(evlist, counter) {
1881 		if (evsel__enable(counter))
1882 			goto out_delete_evlist;
1883 	}
1884 
1885 	evlist->thread.done = 0;
1886 	if (pthread_create(&evlist->thread.th, NULL, perf_evlist__poll_thread, evlist))
1887 		goto out_delete_evlist;
1888 
1889 	return 0;
1890 
1891 out_delete_evlist:
1892 	evlist__delete(evlist);
1893 	evlist = NULL;
1894 	return -1;
1895 }
1896 
1897 void perf_evlist__stop_sb_thread(struct evlist *evlist)
1898 {
1899 	if (!evlist)
1900 		return;
1901 	evlist->thread.done = 1;
1902 	pthread_join(evlist->thread.th, NULL);
1903 	evlist__delete(evlist);
1904 }
1905