xref: /linux/tools/perf/util/evlist.c (revision 54fcc7f6ec3944ae7c1b0246a999744e33839cdb)
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 "util/mmap.h"
14 #include "thread_map.h"
15 #include "target.h"
16 #include "dwarf-regs.h"
17 #include "evlist.h"
18 #include "evsel.h"
19 #include "record.h"
20 #include "debug.h"
21 #include "units.h"
22 #include "bpf_counter.h"
23 #include <internal/lib.h> // page_size
24 #include "affinity.h"
25 #include "../perf.h"
26 #include "asm/bug.h"
27 #include "bpf-event.h"
28 #include "util/event.h"
29 #include "util/string2.h"
30 #include "util/perf_api_probe.h"
31 #include "util/evsel_fprintf.h"
32 #include "util/pmu.h"
33 #include "util/sample.h"
34 #include "util/bpf-filter.h"
35 #include "util/stat.h"
36 #include "util/util.h"
37 #include "util/env.h"
38 #include "util/intel-tpebs.h"
39 #include "util/metricgroup.h"
40 #include "util/strbuf.h"
41 #include <signal.h>
42 #include <unistd.h>
43 #include <sched.h>
44 #include <stdlib.h>
45 
46 #include "parse-events.h"
47 #include <subcmd/parse-options.h>
48 
49 #include <fcntl.h>
50 #include <sys/ioctl.h>
51 #include <sys/mman.h>
52 #include <sys/prctl.h>
53 #include <sys/timerfd.h>
54 #include <sys/wait.h>
55 
56 #include <linux/bitops.h>
57 #include <linux/hash.h>
58 #include <linux/log2.h>
59 #include <linux/err.h>
60 #include <linux/string.h>
61 #include <linux/time64.h>
62 #include <linux/zalloc.h>
63 #include <perf/evlist.h>
64 #include <perf/evsel.h>
65 #include <perf/cpumap.h>
66 #include <perf/mmap.h>
67 
68 #include <internal/xyarray.h>
69 
70 #ifdef LACKS_SIGQUEUE_PROTOTYPE
71 int sigqueue(pid_t pid, int sig, const union sigval value);
72 #endif
73 
74 #define FD(e, x, y) (*(int *)xyarray__entry(e->core.fd, x, y))
75 #define SID(e, x, y) xyarray__entry(e->core.sample_id, x, y)
76 
77 void evlist__init(struct evlist *evlist, struct perf_cpu_map *cpus,
78 		  struct perf_thread_map *threads)
79 {
80 	perf_evlist__init(&evlist->core);
81 	perf_evlist__set_maps(&evlist->core, cpus, threads);
82 	evlist->workload.pid = -1;
83 	evlist->bkw_mmap_state = BKW_MMAP_NOTREADY;
84 	evlist->ctl_fd.fd = -1;
85 	evlist->ctl_fd.ack = -1;
86 	evlist->ctl_fd.pos = -1;
87 	evlist->nr_br_cntr = -1;
88 	metricgroup__rblist_init(&evlist->metric_events);
89 	INIT_LIST_HEAD(&evlist->deferred_samples);
90 }
91 
92 struct evlist *evlist__new(void)
93 {
94 	struct evlist *evlist = zalloc(sizeof(*evlist));
95 
96 	if (evlist != NULL)
97 		evlist__init(evlist, NULL, NULL);
98 
99 	return evlist;
100 }
101 
102 struct evlist *evlist__new_default(const struct target *target, bool sample_callchains)
103 {
104 	struct evlist *evlist = evlist__new();
105 	bool can_profile_kernel;
106 	struct perf_pmu *pmu = NULL;
107 	struct evsel *evsel;
108 	char buf[256];
109 	int err;
110 
111 	if (!evlist)
112 		return NULL;
113 
114 	can_profile_kernel = perf_event_paranoid_check(1);
115 
116 	if (EM_HOST == EM_S390 && sample_callchains) {
117 		snprintf(buf, sizeof(buf), "software/%s/%s",
118 			 target__has_cpu(target) ? "cpu-clock" : "task-clock",
119 			 can_profile_kernel ? "P" : "Pu");
120 		err = parse_event(evlist, buf);
121 		if (err)
122 			goto out_err;
123 	} else {
124 		while ((pmu = perf_pmus__scan_core(pmu)) != NULL) {
125 			snprintf(buf, sizeof(buf), "%s/cycles/%s", pmu->name,
126 				can_profile_kernel ? "P" : "Pu");
127 			err = parse_event(evlist, buf);
128 			if (err)
129 				goto out_err;
130 		}
131 	}
132 
133 	/* If there is only 1 event a sample identifier isn't necessary. */
134 	if (evlist->core.nr_entries > 1) {
135 		evlist__for_each_entry(evlist, evsel)
136 			evsel__set_sample_id(evsel, /*can_sample_identifier=*/false);
137 	}
138 
139 	return evlist;
140 out_err:
141 	evlist__delete(evlist);
142 	return NULL;
143 }
144 
145 struct evlist *evlist__new_dummy(void)
146 {
147 	struct evlist *evlist = evlist__new();
148 
149 	if (evlist && evlist__add_dummy(evlist)) {
150 		evlist__delete(evlist);
151 		evlist = NULL;
152 	}
153 
154 	return evlist;
155 }
156 
157 /**
158  * evlist__set_id_pos - set the positions of event ids.
159  * @evlist: selected event list
160  *
161  * Events with compatible sample types all have the same id_pos
162  * and is_pos.  For convenience, put a copy on evlist.
163  */
164 void evlist__set_id_pos(struct evlist *evlist)
165 {
166 	struct evsel *first = evlist__first(evlist);
167 
168 	evlist->id_pos = first->id_pos;
169 	evlist->is_pos = first->is_pos;
170 }
171 
172 static void evlist__update_id_pos(struct evlist *evlist)
173 {
174 	struct evsel *evsel;
175 
176 	evlist__for_each_entry(evlist, evsel)
177 		evsel__calc_id_pos(evsel);
178 
179 	evlist__set_id_pos(evlist);
180 }
181 
182 static void evlist__purge(struct evlist *evlist)
183 {
184 	struct evsel *pos, *n;
185 
186 	evlist__for_each_entry_safe(evlist, n, pos) {
187 		list_del_init(&pos->core.node);
188 		pos->evlist = NULL;
189 		evsel__delete(pos);
190 	}
191 
192 	evlist->core.nr_entries = 0;
193 }
194 
195 void evlist__exit(struct evlist *evlist)
196 {
197 	metricgroup__rblist_exit(&evlist->metric_events);
198 	event_enable_timer__exit(&evlist->eet);
199 	zfree(&evlist->mmap);
200 	zfree(&evlist->overwrite_mmap);
201 	perf_evlist__exit(&evlist->core);
202 }
203 
204 void evlist__delete(struct evlist *evlist)
205 {
206 	if (evlist == NULL)
207 		return;
208 
209 	evlist__free_stats(evlist);
210 	evlist__munmap(evlist);
211 	evlist__close(evlist);
212 	evlist__purge(evlist);
213 	evlist__exit(evlist);
214 	free(evlist);
215 }
216 
217 void evlist__add(struct evlist *evlist, struct evsel *entry)
218 {
219 	perf_evlist__add(&evlist->core, &entry->core);
220 	entry->evlist = evlist;
221 	entry->tracking = !entry->core.idx;
222 
223 	if (evlist->core.nr_entries == 1)
224 		evlist__set_id_pos(evlist);
225 }
226 
227 void evlist__remove(struct evlist *evlist, struct evsel *evsel)
228 {
229 	evsel->evlist = NULL;
230 	perf_evlist__remove(&evlist->core, &evsel->core);
231 }
232 
233 void evlist__splice_list_tail(struct evlist *evlist, struct list_head *list)
234 {
235 	while (!list_empty(list)) {
236 		struct evsel *evsel, *temp, *leader = NULL;
237 
238 		__evlist__for_each_entry_safe(list, temp, evsel) {
239 			list_del_init(&evsel->core.node);
240 			evlist__add(evlist, evsel);
241 			leader = evsel;
242 			break;
243 		}
244 
245 		__evlist__for_each_entry_safe(list, temp, evsel) {
246 			if (evsel__has_leader(evsel, leader)) {
247 				list_del_init(&evsel->core.node);
248 				evlist__add(evlist, evsel);
249 			}
250 		}
251 	}
252 }
253 
254 int __evlist__set_tracepoints_handlers(struct evlist *evlist,
255 				       const struct evsel_str_handler *assocs, size_t nr_assocs)
256 {
257 	size_t i;
258 	int err;
259 
260 	for (i = 0; i < nr_assocs; i++) {
261 		// Adding a handler for an event not in this evlist, just ignore it.
262 		struct evsel *evsel = evlist__find_tracepoint_by_name(evlist, assocs[i].name);
263 		if (evsel == NULL)
264 			continue;
265 
266 		err = -EEXIST;
267 		if (evsel->handler != NULL)
268 			goto out;
269 		evsel->handler = assocs[i].handler;
270 	}
271 
272 	err = 0;
273 out:
274 	return err;
275 }
276 
277 static void evlist__set_leader(struct evlist *evlist)
278 {
279 	perf_evlist__set_leader(&evlist->core);
280 }
281 
282 static struct evsel *evlist__dummy_event(struct evlist *evlist)
283 {
284 	struct perf_event_attr attr = {
285 		.type	= PERF_TYPE_SOFTWARE,
286 		.config = PERF_COUNT_SW_DUMMY,
287 		.size	= sizeof(attr), /* to capture ABI version */
288 		/* Avoid frequency mode for dummy events to avoid associated timers. */
289 		.freq = 0,
290 		.sample_period = 1,
291 	};
292 
293 	return evsel__new_idx(&attr, evlist->core.nr_entries);
294 }
295 
296 int evlist__add_dummy(struct evlist *evlist)
297 {
298 	struct evsel *evsel = evlist__dummy_event(evlist);
299 
300 	if (evsel == NULL)
301 		return -ENOMEM;
302 
303 	evlist__add(evlist, evsel);
304 	return 0;
305 }
306 
307 struct evsel *evlist__add_aux_dummy(struct evlist *evlist, bool system_wide)
308 {
309 	struct evsel *evsel = evlist__dummy_event(evlist);
310 
311 	if (!evsel)
312 		return NULL;
313 
314 	evsel->core.attr.exclude_kernel = 1;
315 	evsel->core.attr.exclude_guest = 1;
316 	evsel->core.attr.exclude_hv = 1;
317 	evsel->core.system_wide = system_wide;
318 	evsel->no_aux_samples = true;
319 	evsel->name = strdup("dummy:u");
320 
321 	evlist__add(evlist, evsel);
322 	return evsel;
323 }
324 
325 #ifdef HAVE_LIBTRACEEVENT
326 struct evsel *evlist__add_sched_switch(struct evlist *evlist, bool system_wide)
327 {
328 	struct evsel *evsel = evsel__newtp_idx("sched", "sched_switch", 0,
329 					       /*format=*/true);
330 
331 	if (IS_ERR(evsel))
332 		return evsel;
333 
334 	evsel__set_sample_bit(evsel, CPU);
335 	evsel__set_sample_bit(evsel, TIME);
336 
337 	evsel->core.system_wide = system_wide;
338 	evsel->no_aux_samples = true;
339 
340 	evlist__add(evlist, evsel);
341 	return evsel;
342 }
343 #endif
344 
345 struct evsel *evlist__find_tracepoint_by_name(struct evlist *evlist, const char *name)
346 {
347 	struct evsel *evsel;
348 
349 	evlist__for_each_entry(evlist, evsel) {
350 		if ((evsel->core.attr.type == PERF_TYPE_TRACEPOINT) &&
351 		    (strcmp(evsel->name, name) == 0))
352 			return evsel;
353 	}
354 
355 	return NULL;
356 }
357 
358 #ifdef HAVE_LIBTRACEEVENT
359 int evlist__add_newtp(struct evlist *evlist, const char *sys, const char *name, void *handler)
360 {
361 	struct evsel *evsel = evsel__newtp(sys, name);
362 
363 	if (IS_ERR(evsel))
364 		return -1;
365 
366 	evsel->handler = handler;
367 	evlist__add(evlist, evsel);
368 	return 0;
369 }
370 #endif
371 
372 /*
373  * Should sched_setaffinity be used with evlist__for_each_cpu? Determine if
374  * migrating the thread will avoid possibly numerous IPIs.
375  */
376 static bool evlist__use_affinity(struct evlist *evlist)
377 {
378 	struct evsel *pos;
379 	struct perf_cpu_map *used_cpus = NULL;
380 	bool ret = false;
381 
382 	if (evlist->no_affinity || !evlist->core.user_requested_cpus ||
383 	    cpu_map__is_dummy(evlist->core.user_requested_cpus))
384 		return false;
385 
386 	evlist__for_each_entry(evlist, pos) {
387 		struct perf_cpu_map *intersect;
388 
389 		if (!perf_pmu__benefits_from_affinity(pos->pmu))
390 			continue;
391 
392 		if (evsel__is_dummy_event(pos)) {
393 			/*
394 			 * The dummy event is opened on all CPUs so assume >1
395 			 * event with shared CPUs.
396 			 */
397 			ret = true;
398 			break;
399 		}
400 		if (evsel__is_retire_lat(pos)) {
401 			/*
402 			 * Retirement latency events are similar to tool ones in
403 			 * their implementation, and so don't require affinity.
404 			 */
405 			continue;
406 		}
407 		if (perf_cpu_map__is_empty(used_cpus)) {
408 			/* First benefitting event, we want >1 on a common CPU. */
409 			used_cpus = perf_cpu_map__get(pos->core.cpus);
410 			continue;
411 		}
412 		if ((pos->core.attr.read_format & PERF_FORMAT_GROUP) &&
413 		    evsel__leader(pos) != pos) {
414 			/* Skip members of the same sample group. */
415 			continue;
416 		}
417 		intersect = perf_cpu_map__intersect(used_cpus, pos->core.cpus);
418 		if (!perf_cpu_map__is_empty(intersect)) {
419 			/* >1 event with shared CPUs. */
420 			perf_cpu_map__put(intersect);
421 			ret = true;
422 			break;
423 		}
424 		perf_cpu_map__put(intersect);
425 		perf_cpu_map__merge(&used_cpus, pos->core.cpus);
426 	}
427 	perf_cpu_map__put(used_cpus);
428 	return ret;
429 }
430 
431 void evlist_cpu_iterator__init(struct evlist_cpu_iterator *itr, struct evlist *evlist)
432 {
433 	*itr = (struct evlist_cpu_iterator){
434 		.container = evlist,
435 		.evsel = NULL,
436 		.cpu_map_idx = 0,
437 		.evlist_cpu_map_idx = 0,
438 		.evlist_cpu_map_nr = perf_cpu_map__nr(evlist->core.all_cpus),
439 		.cpu = (struct perf_cpu){ .cpu = -1},
440 		.affinity = NULL,
441 	};
442 
443 	if (evlist__empty(evlist)) {
444 		/* Ensure the empty list doesn't iterate. */
445 		itr->evlist_cpu_map_idx = itr->evlist_cpu_map_nr;
446 		return;
447 	}
448 
449 	if (evlist__use_affinity(evlist)) {
450 		if (affinity__setup(&itr->saved_affinity) == 0)
451 			itr->affinity = &itr->saved_affinity;
452 	}
453 	itr->evsel = evlist__first(evlist);
454 	itr->cpu = perf_cpu_map__cpu(evlist->core.all_cpus, 0);
455 	if (itr->affinity)
456 		affinity__set(itr->affinity, itr->cpu.cpu);
457 	itr->cpu_map_idx = perf_cpu_map__idx(itr->evsel->core.cpus, itr->cpu);
458 	/*
459 	 * If this CPU isn't in the evsel's cpu map then advance
460 	 * through the list.
461 	 */
462 	if (itr->cpu_map_idx == -1)
463 		evlist_cpu_iterator__next(itr);
464 }
465 
466 void evlist_cpu_iterator__exit(struct evlist_cpu_iterator *itr)
467 {
468 	if (!itr->affinity)
469 		return;
470 
471 	affinity__cleanup(itr->affinity);
472 	itr->affinity = NULL;
473 }
474 
475 void evlist_cpu_iterator__next(struct evlist_cpu_iterator *evlist_cpu_itr)
476 {
477 	while (evlist_cpu_itr->evsel != evlist__last(evlist_cpu_itr->container)) {
478 		evlist_cpu_itr->evsel = evsel__next(evlist_cpu_itr->evsel);
479 		evlist_cpu_itr->cpu_map_idx =
480 			perf_cpu_map__idx(evlist_cpu_itr->evsel->core.cpus,
481 					  evlist_cpu_itr->cpu);
482 		if (evlist_cpu_itr->cpu_map_idx != -1)
483 			return;
484 	}
485 	evlist_cpu_itr->evlist_cpu_map_idx++;
486 	if (evlist_cpu_itr->evlist_cpu_map_idx < evlist_cpu_itr->evlist_cpu_map_nr) {
487 		evlist_cpu_itr->evsel = evlist__first(evlist_cpu_itr->container);
488 		evlist_cpu_itr->cpu =
489 			perf_cpu_map__cpu(evlist_cpu_itr->container->core.all_cpus,
490 					  evlist_cpu_itr->evlist_cpu_map_idx);
491 		if (evlist_cpu_itr->affinity)
492 			affinity__set(evlist_cpu_itr->affinity, evlist_cpu_itr->cpu.cpu);
493 		evlist_cpu_itr->cpu_map_idx =
494 			perf_cpu_map__idx(evlist_cpu_itr->evsel->core.cpus,
495 					  evlist_cpu_itr->cpu);
496 		/*
497 		 * If this CPU isn't in the evsel's cpu map then advance through
498 		 * the list.
499 		 */
500 		if (evlist_cpu_itr->cpu_map_idx == -1)
501 			evlist_cpu_iterator__next(evlist_cpu_itr);
502 	} else {
503 		evlist_cpu_iterator__exit(evlist_cpu_itr);
504 	}
505 }
506 
507 static int evsel__strcmp(struct evsel *pos, char *evsel_name)
508 {
509 	if (!evsel_name)
510 		return 0;
511 	if (evsel__is_dummy_event(pos))
512 		return 1;
513 	return !evsel__name_is(pos, evsel_name);
514 }
515 
516 static int evlist__is_enabled(struct evlist *evlist)
517 {
518 	struct evsel *pos;
519 
520 	evlist__for_each_entry(evlist, pos) {
521 		if (!evsel__is_group_leader(pos) || !pos->core.fd)
522 			continue;
523 		/* If at least one event is enabled, evlist is enabled. */
524 		if (!pos->disabled)
525 			return true;
526 	}
527 	return false;
528 }
529 
530 static void __evlist__disable(struct evlist *evlist, char *evsel_name, bool excl_dummy)
531 {
532 	struct evsel *pos;
533 	struct evlist_cpu_iterator evlist_cpu_itr;
534 	bool has_imm = false;
535 
536 	/* Disable 'immediate' events last */
537 	for (int imm = 0; imm <= 1; imm++) {
538 		evlist__for_each_cpu(evlist_cpu_itr, evlist) {
539 			pos = evlist_cpu_itr.evsel;
540 			if (evsel__strcmp(pos, evsel_name))
541 				continue;
542 			if (pos->disabled || !evsel__is_group_leader(pos) || !pos->core.fd)
543 				continue;
544 			if (excl_dummy && evsel__is_dummy_event(pos))
545 				continue;
546 			if (pos->immediate)
547 				has_imm = true;
548 			if (pos->immediate != imm)
549 				continue;
550 			evsel__disable_cpu(pos, evlist_cpu_itr.cpu_map_idx);
551 		}
552 		if (!has_imm)
553 			break;
554 	}
555 
556 	evlist__for_each_entry(evlist, pos) {
557 		if (evsel__strcmp(pos, evsel_name))
558 			continue;
559 		if (!evsel__is_group_leader(pos) || !pos->core.fd)
560 			continue;
561 		if (excl_dummy && evsel__is_dummy_event(pos))
562 			continue;
563 		pos->disabled = true;
564 	}
565 
566 	/*
567 	 * If we disabled only single event, we need to check
568 	 * the enabled state of the evlist manually.
569 	 */
570 	if (evsel_name)
571 		evlist->enabled = evlist__is_enabled(evlist);
572 	else
573 		evlist->enabled = false;
574 }
575 
576 void evlist__disable(struct evlist *evlist)
577 {
578 	__evlist__disable(evlist, NULL, false);
579 }
580 
581 void evlist__disable_non_dummy(struct evlist *evlist)
582 {
583 	__evlist__disable(evlist, NULL, true);
584 }
585 
586 void evlist__disable_evsel(struct evlist *evlist, char *evsel_name)
587 {
588 	__evlist__disable(evlist, evsel_name, false);
589 }
590 
591 static void __evlist__enable(struct evlist *evlist, char *evsel_name, bool excl_dummy)
592 {
593 	struct evsel *pos;
594 	struct evlist_cpu_iterator evlist_cpu_itr;
595 
596 	evlist__for_each_cpu(evlist_cpu_itr, evlist) {
597 		pos = evlist_cpu_itr.evsel;
598 		if (evsel__strcmp(pos, evsel_name))
599 			continue;
600 		if (!evsel__is_group_leader(pos) || !pos->core.fd)
601 			continue;
602 		if (excl_dummy && evsel__is_dummy_event(pos))
603 			continue;
604 		evsel__enable_cpu(pos, evlist_cpu_itr.cpu_map_idx);
605 	}
606 	evlist__for_each_entry(evlist, pos) {
607 		if (evsel__strcmp(pos, evsel_name))
608 			continue;
609 		if (!evsel__is_group_leader(pos) || !pos->core.fd)
610 			continue;
611 		if (excl_dummy && evsel__is_dummy_event(pos))
612 			continue;
613 		pos->disabled = false;
614 	}
615 
616 	/*
617 	 * Even single event sets the 'enabled' for evlist,
618 	 * so the toggle can work properly and toggle to
619 	 * 'disabled' state.
620 	 */
621 	evlist->enabled = true;
622 }
623 
624 void evlist__enable(struct evlist *evlist)
625 {
626 	__evlist__enable(evlist, NULL, false);
627 }
628 
629 void evlist__enable_non_dummy(struct evlist *evlist)
630 {
631 	__evlist__enable(evlist, NULL, true);
632 }
633 
634 void evlist__enable_evsel(struct evlist *evlist, char *evsel_name)
635 {
636 	__evlist__enable(evlist, evsel_name, false);
637 }
638 
639 void evlist__toggle_enable(struct evlist *evlist)
640 {
641 	(evlist->enabled ? evlist__disable : evlist__enable)(evlist);
642 }
643 
644 int evlist__add_pollfd(struct evlist *evlist, int fd)
645 {
646 	return perf_evlist__add_pollfd(&evlist->core, fd, NULL, POLLIN, fdarray_flag__default);
647 }
648 
649 int evlist__filter_pollfd(struct evlist *evlist, short revents_and_mask)
650 {
651 	return perf_evlist__filter_pollfd(&evlist->core, revents_and_mask);
652 }
653 
654 #ifdef HAVE_EVENTFD_SUPPORT
655 int evlist__add_wakeup_eventfd(struct evlist *evlist, int fd)
656 {
657 	return perf_evlist__add_pollfd(&evlist->core, fd, NULL, POLLIN,
658 				       fdarray_flag__nonfilterable |
659 				       fdarray_flag__non_perf_event);
660 }
661 #endif
662 
663 int evlist__poll(struct evlist *evlist, int timeout)
664 {
665 	return perf_evlist__poll(&evlist->core, timeout);
666 }
667 
668 struct perf_sample_id *evlist__id2sid(struct evlist *evlist, u64 id)
669 {
670 	struct hlist_head *head;
671 	struct perf_sample_id *sid;
672 	int hash;
673 
674 	hash = hash_64(id, PERF_EVLIST__HLIST_BITS);
675 	head = &evlist->core.heads[hash];
676 
677 	hlist_for_each_entry(sid, head, node)
678 		if (sid->id == id)
679 			return sid;
680 
681 	return NULL;
682 }
683 
684 struct evsel *evlist__id2evsel(struct evlist *evlist, u64 id)
685 {
686 	struct perf_sample_id *sid;
687 
688 	if (evlist->core.nr_entries == 1 || !id)
689 		return evlist__first(evlist);
690 
691 	sid = evlist__id2sid(evlist, id);
692 	if (sid)
693 		return container_of(sid->evsel, struct evsel, core);
694 
695 	if (!evlist__sample_id_all(evlist))
696 		return evlist__first(evlist);
697 
698 	return NULL;
699 }
700 
701 struct evsel *evlist__id2evsel_strict(struct evlist *evlist, u64 id)
702 {
703 	struct perf_sample_id *sid;
704 
705 	if (!id)
706 		return NULL;
707 
708 	sid = evlist__id2sid(evlist, id);
709 	if (sid)
710 		return container_of(sid->evsel, struct evsel, core);
711 
712 	return NULL;
713 }
714 
715 static int evlist__event2id(struct evlist *evlist, union perf_event *event, u64 *id)
716 {
717 	const __u64 *array = event->sample.array;
718 	ssize_t n;
719 
720 	n = (event->header.size - sizeof(event->header)) >> 3;
721 
722 	if (event->header.type == PERF_RECORD_SAMPLE) {
723 		if (evlist->id_pos >= n)
724 			return -1;
725 		*id = array[evlist->id_pos];
726 	} else {
727 		if (evlist->is_pos > n)
728 			return -1;
729 		n -= evlist->is_pos;
730 		*id = array[n];
731 	}
732 	return 0;
733 }
734 
735 struct evsel *evlist__event2evsel(struct evlist *evlist, union perf_event *event)
736 {
737 	struct evsel *first = evlist__first(evlist);
738 	struct hlist_head *head;
739 	struct perf_sample_id *sid;
740 	int hash;
741 	u64 id;
742 
743 	if (evlist->core.nr_entries == 1)
744 		return first;
745 
746 	if (!first->core.attr.sample_id_all &&
747 	    event->header.type != PERF_RECORD_SAMPLE)
748 		return first;
749 
750 	if (evlist__event2id(evlist, event, &id))
751 		return NULL;
752 
753 	/* Synthesized events have an id of zero */
754 	if (!id)
755 		return first;
756 
757 	hash = hash_64(id, PERF_EVLIST__HLIST_BITS);
758 	head = &evlist->core.heads[hash];
759 
760 	hlist_for_each_entry(sid, head, node) {
761 		if (sid->id == id)
762 			return container_of(sid->evsel, struct evsel, core);
763 	}
764 	return NULL;
765 }
766 
767 static int evlist__set_paused(struct evlist *evlist, bool value)
768 {
769 	int i;
770 
771 	if (!evlist->overwrite_mmap)
772 		return 0;
773 
774 	for (i = 0; i < evlist->core.nr_mmaps; i++) {
775 		int fd = evlist->overwrite_mmap[i].core.fd;
776 		int err;
777 
778 		if (fd < 0)
779 			continue;
780 		err = ioctl(fd, PERF_EVENT_IOC_PAUSE_OUTPUT, value ? 1 : 0);
781 		if (err)
782 			return err;
783 	}
784 	return 0;
785 }
786 
787 static int evlist__pause(struct evlist *evlist)
788 {
789 	return evlist__set_paused(evlist, true);
790 }
791 
792 static int evlist__resume(struct evlist *evlist)
793 {
794 	return evlist__set_paused(evlist, false);
795 }
796 
797 static void evlist__munmap_nofree(struct evlist *evlist)
798 {
799 	int i;
800 
801 	if (evlist->mmap)
802 		for (i = 0; i < evlist->core.nr_mmaps; i++)
803 			perf_mmap__munmap(&evlist->mmap[i].core);
804 
805 	if (evlist->overwrite_mmap)
806 		for (i = 0; i < evlist->core.nr_mmaps; i++)
807 			perf_mmap__munmap(&evlist->overwrite_mmap[i].core);
808 }
809 
810 void evlist__munmap(struct evlist *evlist)
811 {
812 	evlist__munmap_nofree(evlist);
813 	zfree(&evlist->mmap);
814 	zfree(&evlist->overwrite_mmap);
815 }
816 
817 static void perf_mmap__unmap_cb(struct perf_mmap *map)
818 {
819 	struct mmap *m = container_of(map, struct mmap, core);
820 
821 	mmap__munmap(m);
822 }
823 
824 static struct mmap *evlist__alloc_mmap(struct evlist *evlist,
825 				       bool overwrite)
826 {
827 	int i;
828 	struct mmap *map;
829 
830 	map = zalloc(evlist->core.nr_mmaps * sizeof(struct mmap));
831 	if (!map)
832 		return NULL;
833 
834 	for (i = 0; i < evlist->core.nr_mmaps; i++) {
835 		struct perf_mmap *prev = i ? &map[i - 1].core : NULL;
836 
837 		/*
838 		 * When the perf_mmap() call is made we grab one refcount, plus
839 		 * one extra to let perf_mmap__consume() get the last
840 		 * events after all real references (perf_mmap__get()) are
841 		 * dropped.
842 		 *
843 		 * Each PERF_EVENT_IOC_SET_OUTPUT points to this mmap and
844 		 * thus does perf_mmap__get() on it.
845 		 */
846 		perf_mmap__init(&map[i].core, prev, overwrite, perf_mmap__unmap_cb);
847 	}
848 
849 	return map;
850 }
851 
852 static void
853 perf_evlist__mmap_cb_idx(struct perf_evlist *_evlist,
854 			 struct perf_evsel *_evsel,
855 			 struct perf_mmap_param *_mp,
856 			 int idx)
857 {
858 	struct evlist *evlist = container_of(_evlist, struct evlist, core);
859 	struct mmap_params *mp = container_of(_mp, struct mmap_params, core);
860 	struct evsel *evsel = container_of(_evsel, struct evsel, core);
861 
862 	auxtrace_mmap_params__set_idx(&mp->auxtrace_mp, evlist, evsel, idx);
863 }
864 
865 static struct perf_mmap*
866 perf_evlist__mmap_cb_get(struct perf_evlist *_evlist, bool overwrite, int idx)
867 {
868 	struct evlist *evlist = container_of(_evlist, struct evlist, core);
869 	struct mmap *maps;
870 
871 	maps = overwrite ? evlist->overwrite_mmap : evlist->mmap;
872 
873 	if (!maps) {
874 		maps = evlist__alloc_mmap(evlist, overwrite);
875 		if (!maps)
876 			return NULL;
877 
878 		if (overwrite) {
879 			evlist->overwrite_mmap = maps;
880 			if (evlist->bkw_mmap_state == BKW_MMAP_NOTREADY)
881 				evlist__toggle_bkw_mmap(evlist, BKW_MMAP_RUNNING);
882 		} else {
883 			evlist->mmap = maps;
884 		}
885 	}
886 
887 	return &maps[idx].core;
888 }
889 
890 static int
891 perf_evlist__mmap_cb_mmap(struct perf_mmap *_map, struct perf_mmap_param *_mp,
892 			  int output, struct perf_cpu cpu)
893 {
894 	struct mmap *map = container_of(_map, struct mmap, core);
895 	struct mmap_params *mp = container_of(_mp, struct mmap_params, core);
896 
897 	return mmap__mmap(map, mp, output, cpu);
898 }
899 
900 unsigned long perf_event_mlock_kb_in_pages(void)
901 {
902 	unsigned long pages;
903 	int max;
904 
905 	if (sysctl__read_int("kernel/perf_event_mlock_kb", &max) < 0) {
906 		/*
907 		 * Pick a once upon a time good value, i.e. things look
908 		 * strange since we can't read a sysctl value, but lets not
909 		 * die yet...
910 		 */
911 		max = 512;
912 	} else {
913 		max -= (page_size / 1024);
914 	}
915 
916 	pages = (max * 1024) / page_size;
917 	if (!is_power_of_2(pages))
918 		pages = rounddown_pow_of_two(pages);
919 
920 	return pages;
921 }
922 
923 size_t evlist__mmap_size(unsigned long pages)
924 {
925 	if (pages == UINT_MAX)
926 		pages = perf_event_mlock_kb_in_pages();
927 	else if (!is_power_of_2(pages))
928 		return 0;
929 
930 	return (pages + 1) * page_size;
931 }
932 
933 static long parse_pages_arg(const char *str, unsigned long min,
934 			    unsigned long max)
935 {
936 	unsigned long pages, val;
937 	static struct parse_tag tags[] = {
938 		{ .tag  = 'B', .mult = 1       },
939 		{ .tag  = 'K', .mult = 1 << 10 },
940 		{ .tag  = 'M', .mult = 1 << 20 },
941 		{ .tag  = 'G', .mult = 1 << 30 },
942 		{ .tag  = 0 },
943 	};
944 
945 	if (str == NULL)
946 		return -EINVAL;
947 
948 	val = parse_tag_value(str, tags);
949 	if (val != (unsigned long) -1) {
950 		/* we got file size value */
951 		pages = PERF_ALIGN(val, page_size) / page_size;
952 	} else {
953 		/* we got pages count value */
954 		char *eptr;
955 		pages = strtoul(str, &eptr, 10);
956 		if (*eptr != '\0')
957 			return -EINVAL;
958 	}
959 
960 	if (pages == 0 && min == 0) {
961 		/* leave number of pages at 0 */
962 	} else if (!is_power_of_2(pages)) {
963 		char buf[100];
964 
965 		/* round pages up to next power of 2 */
966 		pages = roundup_pow_of_two(pages);
967 		if (!pages)
968 			return -EINVAL;
969 
970 		unit_number__scnprintf(buf, sizeof(buf), pages * page_size);
971 		pr_info("rounding mmap pages size to %s (%lu pages)\n",
972 			buf, pages);
973 	}
974 
975 	if (pages > max)
976 		return -EINVAL;
977 
978 	return pages;
979 }
980 
981 int __evlist__parse_mmap_pages(unsigned int *mmap_pages, const char *str)
982 {
983 	unsigned long max = UINT_MAX;
984 	long pages;
985 
986 	if (max > SIZE_MAX / page_size)
987 		max = SIZE_MAX / page_size;
988 
989 	pages = parse_pages_arg(str, 1, max);
990 	if (pages < 0) {
991 		pr_err("Invalid argument for --mmap_pages/-m\n");
992 		return -1;
993 	}
994 
995 	*mmap_pages = pages;
996 	return 0;
997 }
998 
999 int evlist__parse_mmap_pages(const struct option *opt, const char *str, int unset __maybe_unused)
1000 {
1001 	return __evlist__parse_mmap_pages(opt->value, str);
1002 }
1003 
1004 /**
1005  * evlist__mmap_ex - Create mmaps to receive events.
1006  * @evlist: list of events
1007  * @pages: map length in pages
1008  * @overwrite: overwrite older events?
1009  * @auxtrace_pages - auxtrace map length in pages
1010  * @auxtrace_overwrite - overwrite older auxtrace data?
1011  *
1012  * If @overwrite is %false the user needs to signal event consumption using
1013  * perf_mmap__write_tail().  Using evlist__mmap_read() does this
1014  * automatically.
1015  *
1016  * Similarly, if @auxtrace_overwrite is %false the user needs to signal data
1017  * consumption using auxtrace_mmap__write_tail().
1018  *
1019  * Return: %0 on success, negative error code otherwise.
1020  */
1021 int evlist__mmap_ex(struct evlist *evlist, unsigned int pages,
1022 			 unsigned int auxtrace_pages,
1023 			 bool auxtrace_overwrite, int nr_cblocks, int affinity, int flush,
1024 			 int comp_level)
1025 {
1026 	/*
1027 	 * Delay setting mp.prot: set it before calling perf_mmap__mmap.
1028 	 * Its value is decided by evsel's write_backward.
1029 	 * So &mp should not be passed through const pointer.
1030 	 */
1031 	struct mmap_params mp = {
1032 		.nr_cblocks	= nr_cblocks,
1033 		.affinity	= affinity,
1034 		.flush		= flush,
1035 		.comp_level	= comp_level
1036 	};
1037 	struct perf_evlist_mmap_ops ops = {
1038 		.idx  = perf_evlist__mmap_cb_idx,
1039 		.get  = perf_evlist__mmap_cb_get,
1040 		.mmap = perf_evlist__mmap_cb_mmap,
1041 	};
1042 
1043 	evlist->core.mmap_len = evlist__mmap_size(pages);
1044 	pr_debug("mmap size %zuB\n", evlist->core.mmap_len);
1045 
1046 	auxtrace_mmap_params__init(&mp.auxtrace_mp, evlist->core.mmap_len,
1047 				   auxtrace_pages, auxtrace_overwrite);
1048 
1049 	return perf_evlist__mmap_ops(&evlist->core, &ops, &mp.core);
1050 }
1051 
1052 int evlist__mmap(struct evlist *evlist, unsigned int pages)
1053 {
1054 	return evlist__mmap_ex(evlist, pages, 0, false, 0, PERF_AFFINITY_SYS, 1, 0);
1055 }
1056 
1057 int evlist__create_maps(struct evlist *evlist, struct target *target)
1058 {
1059 	bool all_threads = (target->per_thread && target->system_wide);
1060 	struct perf_cpu_map *cpus;
1061 	struct perf_thread_map *threads;
1062 
1063 	/*
1064 	 * If specify '-a' and '--per-thread' to perf record, perf record
1065 	 * will override '--per-thread'. target->per_thread = false and
1066 	 * target->system_wide = true.
1067 	 *
1068 	 * If specify '--per-thread' only to perf record,
1069 	 * target->per_thread = true and target->system_wide = false.
1070 	 *
1071 	 * So target->per_thread && target->system_wide is false.
1072 	 * For perf record, thread_map__new_str doesn't call
1073 	 * thread_map__new_all_cpus. That will keep perf record's
1074 	 * current behavior.
1075 	 *
1076 	 * For perf stat, it allows the case that target->per_thread and
1077 	 * target->system_wide are all true. It means to collect system-wide
1078 	 * per-thread data. thread_map__new_str will call
1079 	 * thread_map__new_all_cpus to enumerate all threads.
1080 	 */
1081 	threads = thread_map__new_str(target->pid, target->tid, all_threads);
1082 
1083 	if (!threads)
1084 		return -1;
1085 
1086 	if (target__uses_dummy_map(target) && !evlist__has_bpf_output(evlist))
1087 		cpus = perf_cpu_map__new_any_cpu();
1088 	else
1089 		cpus = perf_cpu_map__new(target->cpu_list);
1090 
1091 	if (!cpus)
1092 		goto out_delete_threads;
1093 
1094 	evlist->core.has_user_cpus = !!target->cpu_list;
1095 
1096 	perf_evlist__set_maps(&evlist->core, cpus, threads);
1097 
1098 	/* as evlist now has references, put count here */
1099 	perf_cpu_map__put(cpus);
1100 	perf_thread_map__put(threads);
1101 
1102 	return 0;
1103 
1104 out_delete_threads:
1105 	perf_thread_map__put(threads);
1106 	return -1;
1107 }
1108 
1109 int evlist__apply_filters(struct evlist *evlist, struct evsel **err_evsel,
1110 			  struct target *target)
1111 {
1112 	struct evsel *evsel;
1113 	int err = 0;
1114 
1115 	evlist__for_each_entry(evlist, evsel) {
1116 		/*
1117 		 * filters only work for tracepoint event, which doesn't have cpu limit.
1118 		 * So evlist and evsel should always be same.
1119 		 */
1120 		if (evsel->filter) {
1121 			err = perf_evsel__apply_filter(&evsel->core, evsel->filter);
1122 			if (err) {
1123 				*err_evsel = evsel;
1124 				break;
1125 			}
1126 		}
1127 
1128 		/*
1129 		 * non-tracepoint events can have BPF filters.
1130 		 */
1131 		if (!list_empty(&evsel->bpf_filters)) {
1132 			err = perf_bpf_filter__prepare(evsel, target);
1133 			if (err) {
1134 				*err_evsel = evsel;
1135 				break;
1136 			}
1137 		}
1138 	}
1139 
1140 	return err;
1141 }
1142 
1143 int evlist__set_tp_filter(struct evlist *evlist, const char *filter)
1144 {
1145 	struct evsel *evsel;
1146 	int err = 0;
1147 
1148 	if (filter == NULL)
1149 		return -1;
1150 
1151 	evlist__for_each_entry(evlist, evsel) {
1152 		if (evsel->core.attr.type != PERF_TYPE_TRACEPOINT)
1153 			continue;
1154 
1155 		err = evsel__set_filter(evsel, filter);
1156 		if (err)
1157 			break;
1158 	}
1159 
1160 	return err;
1161 }
1162 
1163 int evlist__append_tp_filter(struct evlist *evlist, const char *filter)
1164 {
1165 	struct evsel *evsel;
1166 	int err = 0;
1167 
1168 	if (filter == NULL)
1169 		return -1;
1170 
1171 	evlist__for_each_entry(evlist, evsel) {
1172 		if (evsel->core.attr.type != PERF_TYPE_TRACEPOINT)
1173 			continue;
1174 
1175 		err = evsel__append_tp_filter(evsel, filter);
1176 		if (err)
1177 			break;
1178 	}
1179 
1180 	return err;
1181 }
1182 
1183 char *asprintf__tp_filter_pids(size_t npids, pid_t *pids)
1184 {
1185 	char *filter;
1186 	size_t i;
1187 
1188 	for (i = 0; i < npids; ++i) {
1189 		if (i == 0) {
1190 			if (asprintf(&filter, "common_pid != %d", pids[i]) < 0)
1191 				return NULL;
1192 		} else {
1193 			char *tmp;
1194 
1195 			if (asprintf(&tmp, "%s && common_pid != %d", filter, pids[i]) < 0)
1196 				goto out_free;
1197 
1198 			free(filter);
1199 			filter = tmp;
1200 		}
1201 	}
1202 
1203 	return filter;
1204 out_free:
1205 	free(filter);
1206 	return NULL;
1207 }
1208 
1209 int evlist__set_tp_filter_pids(struct evlist *evlist, size_t npids, pid_t *pids)
1210 {
1211 	char *filter = asprintf__tp_filter_pids(npids, pids);
1212 	int ret = evlist__set_tp_filter(evlist, filter);
1213 
1214 	free(filter);
1215 	return ret;
1216 }
1217 
1218 int evlist__append_tp_filter_pids(struct evlist *evlist, size_t npids, pid_t *pids)
1219 {
1220 	char *filter = asprintf__tp_filter_pids(npids, pids);
1221 	int ret = evlist__append_tp_filter(evlist, filter);
1222 
1223 	free(filter);
1224 	return ret;
1225 }
1226 
1227 int evlist__append_tp_filter_pid(struct evlist *evlist, pid_t pid)
1228 {
1229 	return evlist__append_tp_filter_pids(evlist, 1, &pid);
1230 }
1231 
1232 bool evlist__valid_sample_type(struct evlist *evlist)
1233 {
1234 	struct evsel *pos;
1235 
1236 	if (evlist->core.nr_entries == 1)
1237 		return true;
1238 
1239 	if (evlist->id_pos < 0 || evlist->is_pos < 0)
1240 		return false;
1241 
1242 	evlist__for_each_entry(evlist, pos) {
1243 		if (pos->id_pos != evlist->id_pos ||
1244 		    pos->is_pos != evlist->is_pos)
1245 			return false;
1246 	}
1247 
1248 	return true;
1249 }
1250 
1251 u64 __evlist__combined_sample_type(struct evlist *evlist)
1252 {
1253 	struct evsel *evsel;
1254 
1255 	if (evlist->combined_sample_type)
1256 		return evlist->combined_sample_type;
1257 
1258 	evlist__for_each_entry(evlist, evsel)
1259 		evlist->combined_sample_type |= evsel->core.attr.sample_type;
1260 
1261 	return evlist->combined_sample_type;
1262 }
1263 
1264 u64 evlist__combined_sample_type(struct evlist *evlist)
1265 {
1266 	evlist->combined_sample_type = 0;
1267 	return __evlist__combined_sample_type(evlist);
1268 }
1269 
1270 u64 evlist__combined_branch_type(struct evlist *evlist)
1271 {
1272 	struct evsel *evsel;
1273 	u64 branch_type = 0;
1274 
1275 	evlist__for_each_entry(evlist, evsel)
1276 		branch_type |= evsel->core.attr.branch_sample_type;
1277 	return branch_type;
1278 }
1279 
1280 static struct evsel *
1281 evlist__find_dup_event_from_prev(struct evlist *evlist, struct evsel *event)
1282 {
1283 	struct evsel *pos;
1284 
1285 	evlist__for_each_entry(evlist, pos) {
1286 		if (event == pos)
1287 			break;
1288 		if ((pos->core.attr.branch_sample_type & PERF_SAMPLE_BRANCH_COUNTERS) &&
1289 		    !strcmp(pos->name, event->name))
1290 			return pos;
1291 	}
1292 	return NULL;
1293 }
1294 
1295 #define MAX_NR_ABBR_NAME	(26 * 11)
1296 
1297 /*
1298  * The abbr name is from A to Z9. If the number of event
1299  * which requires the branch counter > MAX_NR_ABBR_NAME,
1300  * return NA.
1301  */
1302 static void evlist__new_abbr_name(char *name)
1303 {
1304 	static int idx;
1305 	int i = idx / 26;
1306 
1307 	if (idx >= MAX_NR_ABBR_NAME) {
1308 		name[0] = 'N';
1309 		name[1] = 'A';
1310 		name[2] = '\0';
1311 		return;
1312 	}
1313 
1314 	name[0] = 'A' + (idx % 26);
1315 
1316 	if (!i)
1317 		name[1] = '\0';
1318 	else {
1319 		name[1] = '0' + i - 1;
1320 		name[2] = '\0';
1321 	}
1322 
1323 	idx++;
1324 }
1325 
1326 void evlist__update_br_cntr(struct evlist *evlist)
1327 {
1328 	struct evsel *evsel, *dup;
1329 	int i = 0;
1330 
1331 	evlist__for_each_entry(evlist, evsel) {
1332 		if (evsel->core.attr.branch_sample_type & PERF_SAMPLE_BRANCH_COUNTERS) {
1333 			evsel->br_cntr_idx = i++;
1334 			evsel__leader(evsel)->br_cntr_nr++;
1335 
1336 			dup = evlist__find_dup_event_from_prev(evlist, evsel);
1337 			if (dup)
1338 				memcpy(evsel->abbr_name, dup->abbr_name, 3 * sizeof(char));
1339 			else
1340 				evlist__new_abbr_name(evsel->abbr_name);
1341 		}
1342 	}
1343 	evlist->nr_br_cntr = i;
1344 }
1345 
1346 bool evlist__valid_read_format(struct evlist *evlist)
1347 {
1348 	struct evsel *first = evlist__first(evlist), *pos = first;
1349 	u64 read_format = first->core.attr.read_format;
1350 	u64 sample_type = first->core.attr.sample_type;
1351 
1352 	evlist__for_each_entry(evlist, pos) {
1353 		if (read_format != pos->core.attr.read_format) {
1354 			pr_debug("Read format differs %#" PRIx64 " vs %#" PRIx64 "\n",
1355 				 read_format, (u64)pos->core.attr.read_format);
1356 		}
1357 	}
1358 
1359 	/* PERF_SAMPLE_READ implies PERF_FORMAT_ID. */
1360 	if ((sample_type & PERF_SAMPLE_READ) &&
1361 	    !(read_format & PERF_FORMAT_ID)) {
1362 		return false;
1363 	}
1364 
1365 	return true;
1366 }
1367 
1368 u16 evlist__id_hdr_size(struct evlist *evlist)
1369 {
1370 	struct evsel *first = evlist__first(evlist);
1371 
1372 	return first->core.attr.sample_id_all ? evsel__id_hdr_size(first) : 0;
1373 }
1374 
1375 bool evlist__valid_sample_id_all(struct evlist *evlist)
1376 {
1377 	struct evsel *first = evlist__first(evlist), *pos = first;
1378 
1379 	evlist__for_each_entry_continue(evlist, pos) {
1380 		if (first->core.attr.sample_id_all != pos->core.attr.sample_id_all)
1381 			return false;
1382 	}
1383 
1384 	return true;
1385 }
1386 
1387 bool evlist__sample_id_all(struct evlist *evlist)
1388 {
1389 	struct evsel *first = evlist__first(evlist);
1390 	return first->core.attr.sample_id_all;
1391 }
1392 
1393 void evlist__set_selected(struct evlist *evlist, struct evsel *evsel)
1394 {
1395 	evlist->selected = evsel;
1396 }
1397 
1398 void evlist__close(struct evlist *evlist)
1399 {
1400 	struct evsel *evsel;
1401 	struct evlist_cpu_iterator evlist_cpu_itr;
1402 
1403 	evlist__for_each_cpu(evlist_cpu_itr, evlist) {
1404 		if (evlist_cpu_itr.cpu_map_idx == 0 && evsel__is_retire_lat(evlist_cpu_itr.evsel))
1405 			evsel__tpebs_close(evlist_cpu_itr.evsel);
1406 		perf_evsel__close_cpu(&evlist_cpu_itr.evsel->core,
1407 				      evlist_cpu_itr.cpu_map_idx);
1408 	}
1409 
1410 	evlist__for_each_entry_reverse(evlist, evsel) {
1411 		perf_evsel__free_fd(&evsel->core);
1412 		perf_evsel__free_id(&evsel->core);
1413 	}
1414 	perf_evlist__reset_id_hash(&evlist->core);
1415 }
1416 
1417 static int evlist__create_syswide_maps(struct evlist *evlist)
1418 {
1419 	struct perf_cpu_map *cpus;
1420 	struct perf_thread_map *threads;
1421 
1422 	/*
1423 	 * Try reading /sys/devices/system/cpu/online to get
1424 	 * an all cpus map.
1425 	 *
1426 	 * FIXME: -ENOMEM is the best we can do here, the cpu_map
1427 	 * code needs an overhaul to properly forward the
1428 	 * error, and we may not want to do that fallback to a
1429 	 * default cpu identity map :-\
1430 	 */
1431 	cpus = perf_cpu_map__new_online_cpus();
1432 	if (!cpus)
1433 		return -ENOMEM;
1434 
1435 	threads = perf_thread_map__new_dummy();
1436 	if (!threads) {
1437 		perf_cpu_map__put(cpus);
1438 		return -ENOMEM;
1439 	}
1440 
1441 	perf_evlist__set_maps(&evlist->core, cpus, threads);
1442 	perf_thread_map__put(threads);
1443 	perf_cpu_map__put(cpus);
1444 	return 0;
1445 }
1446 
1447 int evlist__open(struct evlist *evlist)
1448 {
1449 	struct evsel *evsel;
1450 	int err;
1451 
1452 	/*
1453 	 * Default: one fd per CPU, all threads, aka systemwide
1454 	 * as sys_perf_event_open(cpu = -1, thread = -1) is EINVAL
1455 	 */
1456 	if (evlist->core.threads == NULL && evlist->core.user_requested_cpus == NULL) {
1457 		err = evlist__create_syswide_maps(evlist);
1458 		if (err < 0)
1459 			goto out_err;
1460 	}
1461 
1462 	evlist__update_id_pos(evlist);
1463 
1464 	evlist__for_each_entry(evlist, evsel) {
1465 		err = evsel__open(evsel, evsel->core.cpus, evsel->core.threads);
1466 		if (err < 0)
1467 			goto out_err;
1468 	}
1469 
1470 	return 0;
1471 out_err:
1472 	evlist__close(evlist);
1473 	errno = -err;
1474 	return err;
1475 }
1476 
1477 int evlist__prepare_workload(struct evlist *evlist, struct target *target, const char *argv[],
1478 			     bool pipe_output, void (*exec_error)(int signo, siginfo_t *info, void *ucontext))
1479 {
1480 	int child_ready_pipe[2], go_pipe[2];
1481 	char bf;
1482 
1483 	evlist->workload.cork_fd = -1;
1484 
1485 	if (pipe(child_ready_pipe) < 0) {
1486 		perror("failed to create 'ready' pipe");
1487 		return -1;
1488 	}
1489 
1490 	if (pipe(go_pipe) < 0) {
1491 		perror("failed to create 'go' pipe");
1492 		goto out_close_ready_pipe;
1493 	}
1494 
1495 	evlist->workload.pid = fork();
1496 	if (evlist->workload.pid < 0) {
1497 		perror("failed to fork");
1498 		goto out_close_pipes;
1499 	}
1500 
1501 	if (!evlist->workload.pid) {
1502 		int ret;
1503 
1504 		if (pipe_output)
1505 			dup2(2, 1);
1506 
1507 		signal(SIGTERM, SIG_DFL);
1508 
1509 		close(child_ready_pipe[0]);
1510 		close(go_pipe[1]);
1511 		fcntl(go_pipe[0], F_SETFD, FD_CLOEXEC);
1512 
1513 		/*
1514 		 * Change the name of this process not to confuse --exclude-perf users
1515 		 * that sees 'perf' in the window up to the execvp() and thinks that
1516 		 * perf samples are not being excluded.
1517 		 */
1518 		prctl(PR_SET_NAME, "perf-exec");
1519 
1520 		/*
1521 		 * Tell the parent we're ready to go
1522 		 */
1523 		close(child_ready_pipe[1]);
1524 
1525 		/*
1526 		 * Wait until the parent tells us to go.
1527 		 */
1528 		ret = read(go_pipe[0], &bf, 1);
1529 		/*
1530 		 * The parent will ask for the execvp() to be performed by
1531 		 * writing exactly one byte, in workload.cork_fd, usually via
1532 		 * evlist__start_workload().
1533 		 *
1534 		 * For cancelling the workload without actually running it,
1535 		 * the parent will just close workload.cork_fd, without writing
1536 		 * anything, i.e. read will return zero and we just exit()
1537 		 * here (See evlist__cancel_workload()).
1538 		 */
1539 		if (ret != 1) {
1540 			if (ret == -1)
1541 				perror("unable to read pipe");
1542 			exit(ret);
1543 		}
1544 
1545 		execvp(argv[0], (char **)argv);
1546 
1547 		if (exec_error) {
1548 			union sigval val;
1549 
1550 			val.sival_int = errno;
1551 			if (sigqueue(getppid(), SIGUSR1, val))
1552 				perror(argv[0]);
1553 		} else
1554 			perror(argv[0]);
1555 		exit(-1);
1556 	}
1557 
1558 	if (exec_error) {
1559 		struct sigaction act = {
1560 			.sa_flags     = SA_SIGINFO,
1561 			.sa_sigaction = exec_error,
1562 		};
1563 		sigaction(SIGUSR1, &act, NULL);
1564 	}
1565 
1566 	if (target__none(target)) {
1567 		if (evlist->core.threads == NULL) {
1568 			fprintf(stderr, "FATAL: evlist->threads need to be set at this point (%s:%d).\n",
1569 				__func__, __LINE__);
1570 			goto out_close_pipes;
1571 		}
1572 		perf_thread_map__set_pid(evlist->core.threads, 0, evlist->workload.pid);
1573 	}
1574 
1575 	close(child_ready_pipe[1]);
1576 	close(go_pipe[0]);
1577 	/*
1578 	 * wait for child to settle
1579 	 */
1580 	if (read(child_ready_pipe[0], &bf, 1) == -1) {
1581 		perror("unable to read pipe");
1582 		goto out_close_pipes;
1583 	}
1584 
1585 	fcntl(go_pipe[1], F_SETFD, FD_CLOEXEC);
1586 	evlist->workload.cork_fd = go_pipe[1];
1587 	close(child_ready_pipe[0]);
1588 	return 0;
1589 
1590 out_close_pipes:
1591 	close(go_pipe[0]);
1592 	close(go_pipe[1]);
1593 out_close_ready_pipe:
1594 	close(child_ready_pipe[0]);
1595 	close(child_ready_pipe[1]);
1596 	return -1;
1597 }
1598 
1599 int evlist__start_workload(struct evlist *evlist)
1600 {
1601 	if (evlist->workload.cork_fd >= 0) {
1602 		char bf = 0;
1603 		int ret;
1604 		/*
1605 		 * Remove the cork, let it rip!
1606 		 */
1607 		ret = write(evlist->workload.cork_fd, &bf, 1);
1608 		if (ret < 0)
1609 			perror("unable to write to pipe");
1610 
1611 		close(evlist->workload.cork_fd);
1612 		evlist->workload.cork_fd = -1;
1613 		return ret;
1614 	}
1615 
1616 	return 0;
1617 }
1618 
1619 void evlist__cancel_workload(struct evlist *evlist)
1620 {
1621 	int status;
1622 
1623 	if (evlist->workload.cork_fd >= 0) {
1624 		close(evlist->workload.cork_fd);
1625 		evlist->workload.cork_fd = -1;
1626 		waitpid(evlist->workload.pid, &status, WNOHANG);
1627 	}
1628 }
1629 
1630 int evlist__parse_sample(struct evlist *evlist, union perf_event *event, struct perf_sample *sample)
1631 {
1632 	struct evsel *evsel = evlist__event2evsel(evlist, event);
1633 	int ret;
1634 
1635 	if (!evsel)
1636 		return -EFAULT;
1637 	ret = evsel__parse_sample(evsel, event, sample);
1638 	if (ret)
1639 		return ret;
1640 	if (perf_guest && sample->id) {
1641 		struct perf_sample_id *sid = evlist__id2sid(evlist, sample->id);
1642 
1643 		if (sid) {
1644 			sample->machine_pid = sid->machine_pid;
1645 			sample->vcpu = sid->vcpu.cpu;
1646 		}
1647 	}
1648 	return 0;
1649 }
1650 
1651 int evlist__parse_sample_timestamp(struct evlist *evlist, union perf_event *event, u64 *timestamp)
1652 {
1653 	struct evsel *evsel = evlist__event2evsel(evlist, event);
1654 
1655 	if (!evsel)
1656 		return -EFAULT;
1657 	return evsel__parse_sample_timestamp(evsel, event, timestamp);
1658 }
1659 
1660 int evlist__strerror_open(struct evlist *evlist, int err, char *buf, size_t size)
1661 {
1662 	int printed, value;
1663 
1664 	switch (err) {
1665 	case EACCES:
1666 	case EPERM:
1667 		errno = err;
1668 		printed = scnprintf(buf, size,
1669 				    "Error:\t%m.\n"
1670 				    "Hint:\tCheck /proc/sys/kernel/perf_event_paranoid setting.");
1671 
1672 		value = perf_event_paranoid();
1673 
1674 		printed += scnprintf(buf + printed, size - printed, "\nHint:\t");
1675 
1676 		if (value >= 2) {
1677 			printed += scnprintf(buf + printed, size - printed,
1678 					     "For your workloads it needs to be <= 1\nHint:\t");
1679 		}
1680 		printed += scnprintf(buf + printed, size - printed,
1681 				     "For system wide tracing it needs to be set to -1.\n");
1682 
1683 		printed += scnprintf(buf + printed, size - printed,
1684 				    "Hint:\tTry: 'sudo sh -c \"echo -1 > /proc/sys/kernel/perf_event_paranoid\"'\n"
1685 				    "Hint:\tThe current value is %d.", value);
1686 		break;
1687 	case EINVAL: {
1688 		struct evsel *first = evlist__first(evlist);
1689 		int max_freq;
1690 
1691 		if (sysctl__read_int("kernel/perf_event_max_sample_rate", &max_freq) < 0)
1692 			goto out_default;
1693 
1694 		if (first->core.attr.sample_freq < (u64)max_freq)
1695 			goto out_default;
1696 
1697 		errno = err;
1698 		printed = scnprintf(buf, size,
1699 				    "Error:\t%m.\n"
1700 				    "Hint:\tCheck /proc/sys/kernel/perf_event_max_sample_rate.\n"
1701 				    "Hint:\tThe current value is %d and %" PRIu64 " is being requested.",
1702 				    max_freq, first->core.attr.sample_freq);
1703 		break;
1704 	}
1705 	default:
1706 out_default:
1707 		errno = err;
1708 		scnprintf(buf, size, "%m");
1709 		break;
1710 	}
1711 
1712 	return 0;
1713 }
1714 
1715 int evlist__strerror_mmap(struct evlist *evlist, int err, char *buf, size_t size)
1716 {
1717 	int pages_attempted = evlist->core.mmap_len / 1024, pages_max_per_user, printed = 0;
1718 
1719 	switch (err) {
1720 	case EPERM:
1721 		sysctl__read_int("kernel/perf_event_mlock_kb", &pages_max_per_user);
1722 		errno = err;
1723 		printed += scnprintf(buf + printed, size - printed,
1724 				     "Error:\t%m.\n"
1725 				     "Hint:\tCheck /proc/sys/kernel/perf_event_mlock_kb (%d kB) setting.\n"
1726 				     "Hint:\tTried using %zd kB.\n",
1727 				     pages_max_per_user, pages_attempted);
1728 
1729 		if (pages_attempted >= pages_max_per_user) {
1730 			printed += scnprintf(buf + printed, size - printed,
1731 					     "Hint:\tTry 'sudo sh -c \"echo %d > /proc/sys/kernel/perf_event_mlock_kb\"', or\n",
1732 					     pages_max_per_user + pages_attempted);
1733 		}
1734 
1735 		printed += scnprintf(buf + printed, size - printed,
1736 				     "Hint:\tTry using a smaller -m/--mmap-pages value.");
1737 		break;
1738 	default:
1739 		errno = err;
1740 		scnprintf(buf, size, "%m");
1741 		break;
1742 	}
1743 
1744 	return 0;
1745 }
1746 
1747 void evlist__to_front(struct evlist *evlist, struct evsel *move_evsel)
1748 {
1749 	struct evsel *evsel, *n;
1750 	LIST_HEAD(move);
1751 
1752 	if (move_evsel == evlist__first(evlist))
1753 		return;
1754 
1755 	evlist__for_each_entry_safe(evlist, n, evsel) {
1756 		if (evsel__leader(evsel) == evsel__leader(move_evsel))
1757 			list_move_tail(&evsel->core.node, &move);
1758 	}
1759 
1760 	list_splice(&move, &evlist->core.entries);
1761 }
1762 
1763 struct evsel *evlist__get_tracking_event(struct evlist *evlist)
1764 {
1765 	struct evsel *evsel;
1766 
1767 	evlist__for_each_entry(evlist, evsel) {
1768 		if (evsel->tracking)
1769 			return evsel;
1770 	}
1771 
1772 	return evlist__first(evlist);
1773 }
1774 
1775 void evlist__set_tracking_event(struct evlist *evlist, struct evsel *tracking_evsel)
1776 {
1777 	struct evsel *evsel;
1778 
1779 	if (tracking_evsel->tracking)
1780 		return;
1781 
1782 	evlist__for_each_entry(evlist, evsel) {
1783 		if (evsel != tracking_evsel)
1784 			evsel->tracking = false;
1785 	}
1786 
1787 	tracking_evsel->tracking = true;
1788 }
1789 
1790 struct evsel *evlist__findnew_tracking_event(struct evlist *evlist, bool system_wide)
1791 {
1792 	struct evsel *evsel;
1793 
1794 	evsel = evlist__get_tracking_event(evlist);
1795 	if (!evsel__is_dummy_event(evsel)) {
1796 		evsel = evlist__add_aux_dummy(evlist, system_wide);
1797 		if (!evsel)
1798 			return NULL;
1799 
1800 		evlist__set_tracking_event(evlist, evsel);
1801 	} else if (system_wide) {
1802 		perf_evlist__go_system_wide(&evlist->core, &evsel->core);
1803 	}
1804 
1805 	return evsel;
1806 }
1807 
1808 struct evsel *evlist__find_evsel_by_str(struct evlist *evlist, const char *str)
1809 {
1810 	struct evsel *evsel;
1811 
1812 	evlist__for_each_entry(evlist, evsel) {
1813 		if (!evsel->name)
1814 			continue;
1815 		if (evsel__name_is(evsel, str))
1816 			return evsel;
1817 	}
1818 
1819 	return NULL;
1820 }
1821 
1822 void evlist__toggle_bkw_mmap(struct evlist *evlist, enum bkw_mmap_state state)
1823 {
1824 	enum bkw_mmap_state old_state = evlist->bkw_mmap_state;
1825 	enum action {
1826 		NONE,
1827 		PAUSE,
1828 		RESUME,
1829 	} action = NONE;
1830 
1831 	if (!evlist->overwrite_mmap)
1832 		return;
1833 
1834 	switch (old_state) {
1835 	case BKW_MMAP_NOTREADY: {
1836 		if (state != BKW_MMAP_RUNNING)
1837 			goto state_err;
1838 		break;
1839 	}
1840 	case BKW_MMAP_RUNNING: {
1841 		if (state != BKW_MMAP_DATA_PENDING)
1842 			goto state_err;
1843 		action = PAUSE;
1844 		break;
1845 	}
1846 	case BKW_MMAP_DATA_PENDING: {
1847 		if (state != BKW_MMAP_EMPTY)
1848 			goto state_err;
1849 		break;
1850 	}
1851 	case BKW_MMAP_EMPTY: {
1852 		if (state != BKW_MMAP_RUNNING)
1853 			goto state_err;
1854 		action = RESUME;
1855 		break;
1856 	}
1857 	default:
1858 		WARN_ONCE(1, "Shouldn't get there\n");
1859 	}
1860 
1861 	evlist->bkw_mmap_state = state;
1862 
1863 	switch (action) {
1864 	case PAUSE:
1865 		evlist__pause(evlist);
1866 		break;
1867 	case RESUME:
1868 		evlist__resume(evlist);
1869 		break;
1870 	case NONE:
1871 	default:
1872 		break;
1873 	}
1874 
1875 state_err:
1876 	return;
1877 }
1878 
1879 bool evlist__exclude_kernel(struct evlist *evlist)
1880 {
1881 	struct evsel *evsel;
1882 
1883 	evlist__for_each_entry(evlist, evsel) {
1884 		if (!evsel->core.attr.exclude_kernel)
1885 			return false;
1886 	}
1887 
1888 	return true;
1889 }
1890 
1891 /*
1892  * Events in data file are not collect in groups, but we still want
1893  * the group display. Set the artificial group and set the leader's
1894  * forced_leader flag to notify the display code.
1895  */
1896 void evlist__force_leader(struct evlist *evlist)
1897 {
1898 	if (evlist__nr_groups(evlist) == 0) {
1899 		struct evsel *leader = evlist__first(evlist);
1900 
1901 		evlist__set_leader(evlist);
1902 		leader->forced_leader = true;
1903 	}
1904 }
1905 
1906 struct evsel *evlist__reset_weak_group(struct evlist *evsel_list, struct evsel *evsel, bool close)
1907 {
1908 	struct evsel *c2, *leader;
1909 	bool is_open = true;
1910 
1911 	leader = evsel__leader(evsel);
1912 
1913 	pr_debug("Weak group for %s/%d failed\n",
1914 			leader->name, leader->core.nr_members);
1915 
1916 	/*
1917 	 * for_each_group_member doesn't work here because it doesn't
1918 	 * include the first entry.
1919 	 */
1920 	evlist__for_each_entry(evsel_list, c2) {
1921 		if (c2 == evsel)
1922 			is_open = false;
1923 		if (evsel__has_leader(c2, leader)) {
1924 			if (is_open && close)
1925 				perf_evsel__close(&c2->core);
1926 			/*
1927 			 * We want to close all members of the group and reopen
1928 			 * them. Some events, like Intel topdown, require being
1929 			 * in a group and so keep these in the group.
1930 			 */
1931 			evsel__remove_from_group(c2, leader);
1932 
1933 			/*
1934 			 * Set this for all former members of the group
1935 			 * to indicate they get reopened.
1936 			 */
1937 			c2->reset_group = true;
1938 		}
1939 	}
1940 	/* Reset the leader count if all entries were removed. */
1941 	if (leader->core.nr_members == 1)
1942 		leader->core.nr_members = 0;
1943 	return leader;
1944 }
1945 
1946 static int evlist__parse_control_fifo(const char *str, int *ctl_fd, int *ctl_fd_ack, bool *ctl_fd_close)
1947 {
1948 	char *s, *p;
1949 	int ret = 0, fd;
1950 
1951 	if (strncmp(str, "fifo:", 5))
1952 		return -EINVAL;
1953 
1954 	str += 5;
1955 	if (!*str || *str == ',')
1956 		return -EINVAL;
1957 
1958 	s = strdup(str);
1959 	if (!s)
1960 		return -ENOMEM;
1961 
1962 	p = strchr(s, ',');
1963 	if (p)
1964 		*p = '\0';
1965 
1966 	/*
1967 	 * O_RDWR avoids POLLHUPs which is necessary to allow the other
1968 	 * end of a FIFO to be repeatedly opened and closed.
1969 	 */
1970 	fd = open(s, O_RDWR | O_NONBLOCK | O_CLOEXEC);
1971 	if (fd < 0) {
1972 		ret = -errno;
1973 		pr_err("Failed to open '%s': %m\n", s);
1974 		goto out_free;
1975 	}
1976 	*ctl_fd = fd;
1977 	*ctl_fd_close = true;
1978 
1979 	if (p && *++p) {
1980 		/* O_RDWR | O_NONBLOCK means the other end need not be open */
1981 		fd = open(p, O_RDWR | O_NONBLOCK | O_CLOEXEC);
1982 		if (fd < 0) {
1983 			pr_err("Failed to open '%s': %m\n", p);
1984 			ret = -errno;
1985 			goto out_free;
1986 		}
1987 		*ctl_fd_ack = fd;
1988 	}
1989 
1990 out_free:
1991 	free(s);
1992 	return ret;
1993 }
1994 
1995 int evlist__parse_control(const char *str, int *ctl_fd, int *ctl_fd_ack, bool *ctl_fd_close)
1996 {
1997 	const char *comma = NULL;
1998 	char *endptr = NULL;
1999 
2000 	*ctl_fd_close = false;
2001 
2002 	if (strncmp(str, "fd:", 3))
2003 		return evlist__parse_control_fifo(str, ctl_fd, ctl_fd_ack, ctl_fd_close);
2004 
2005 	*ctl_fd = strtoul(&str[3], &endptr, 0);
2006 	if (endptr == &str[3])
2007 		return -EINVAL;
2008 
2009 	comma = strchr(str, ',');
2010 	if (comma) {
2011 		if (endptr != comma)
2012 			return -EINVAL;
2013 
2014 		*ctl_fd_ack = strtoul(comma + 1, &endptr, 0);
2015 		if (endptr == comma + 1 || *endptr != '\0')
2016 			return -EINVAL;
2017 	}
2018 
2019 	return 0;
2020 }
2021 
2022 void evlist__close_control(int ctl_fd, int ctl_fd_ack, bool *ctl_fd_close)
2023 {
2024 	if (*ctl_fd_close) {
2025 		*ctl_fd_close = false;
2026 		close(ctl_fd);
2027 		if (ctl_fd_ack >= 0)
2028 			close(ctl_fd_ack);
2029 	}
2030 }
2031 
2032 int evlist__initialize_ctlfd(struct evlist *evlist, int fd, int ack)
2033 {
2034 	if (fd == -1) {
2035 		pr_debug("Control descriptor is not initialized\n");
2036 		return 0;
2037 	}
2038 
2039 	evlist->ctl_fd.pos = perf_evlist__add_pollfd(&evlist->core, fd, NULL, POLLIN,
2040 						     fdarray_flag__nonfilterable |
2041 						     fdarray_flag__non_perf_event);
2042 	if (evlist->ctl_fd.pos < 0) {
2043 		evlist->ctl_fd.pos = -1;
2044 		pr_err("Failed to add ctl fd entry: %m\n");
2045 		return -1;
2046 	}
2047 
2048 	evlist->ctl_fd.fd = fd;
2049 	evlist->ctl_fd.ack = ack;
2050 
2051 	return 0;
2052 }
2053 
2054 bool evlist__ctlfd_initialized(struct evlist *evlist)
2055 {
2056 	return evlist->ctl_fd.pos >= 0;
2057 }
2058 
2059 int evlist__finalize_ctlfd(struct evlist *evlist)
2060 {
2061 	struct pollfd *entries = evlist->core.pollfd.entries;
2062 
2063 	if (!evlist__ctlfd_initialized(evlist))
2064 		return 0;
2065 
2066 	entries[evlist->ctl_fd.pos].fd = -1;
2067 	entries[evlist->ctl_fd.pos].events = 0;
2068 	entries[evlist->ctl_fd.pos].revents = 0;
2069 
2070 	evlist->ctl_fd.pos = -1;
2071 	evlist->ctl_fd.ack = -1;
2072 	evlist->ctl_fd.fd = -1;
2073 
2074 	return 0;
2075 }
2076 
2077 static int evlist__ctlfd_recv(struct evlist *evlist, enum evlist_ctl_cmd *cmd,
2078 			      char *cmd_data, size_t data_size)
2079 {
2080 	int err;
2081 	char c;
2082 	size_t bytes_read = 0;
2083 
2084 	*cmd = EVLIST_CTL_CMD_UNSUPPORTED;
2085 	memset(cmd_data, 0, data_size);
2086 	data_size--;
2087 
2088 	do {
2089 		err = read(evlist->ctl_fd.fd, &c, 1);
2090 		if (err > 0) {
2091 			if (c == '\n' || c == '\0')
2092 				break;
2093 			cmd_data[bytes_read++] = c;
2094 			if (bytes_read == data_size)
2095 				break;
2096 			continue;
2097 		} else if (err == -1) {
2098 			if (errno == EINTR)
2099 				continue;
2100 			if (errno == EAGAIN || errno == EWOULDBLOCK)
2101 				err = 0;
2102 			else
2103 				pr_err("Failed to read from ctlfd %d: %m\n", evlist->ctl_fd.fd);
2104 		}
2105 		break;
2106 	} while (1);
2107 
2108 	pr_debug("Message from ctl_fd: \"%s%s\"\n", cmd_data,
2109 		 bytes_read == data_size ? "" : c == '\n' ? "\\n" : "\\0");
2110 
2111 	if (bytes_read > 0) {
2112 		if (!strncmp(cmd_data, EVLIST_CTL_CMD_ENABLE_TAG,
2113 			     (sizeof(EVLIST_CTL_CMD_ENABLE_TAG)-1))) {
2114 			*cmd = EVLIST_CTL_CMD_ENABLE;
2115 		} else if (!strncmp(cmd_data, EVLIST_CTL_CMD_DISABLE_TAG,
2116 				    (sizeof(EVLIST_CTL_CMD_DISABLE_TAG)-1))) {
2117 			*cmd = EVLIST_CTL_CMD_DISABLE;
2118 		} else if (!strncmp(cmd_data, EVLIST_CTL_CMD_SNAPSHOT_TAG,
2119 				    (sizeof(EVLIST_CTL_CMD_SNAPSHOT_TAG)-1))) {
2120 			*cmd = EVLIST_CTL_CMD_SNAPSHOT;
2121 			pr_debug("is snapshot\n");
2122 		} else if (!strncmp(cmd_data, EVLIST_CTL_CMD_EVLIST_TAG,
2123 				    (sizeof(EVLIST_CTL_CMD_EVLIST_TAG)-1))) {
2124 			*cmd = EVLIST_CTL_CMD_EVLIST;
2125 		} else if (!strncmp(cmd_data, EVLIST_CTL_CMD_STOP_TAG,
2126 				    (sizeof(EVLIST_CTL_CMD_STOP_TAG)-1))) {
2127 			*cmd = EVLIST_CTL_CMD_STOP;
2128 		} else if (!strncmp(cmd_data, EVLIST_CTL_CMD_PING_TAG,
2129 				    (sizeof(EVLIST_CTL_CMD_PING_TAG)-1))) {
2130 			*cmd = EVLIST_CTL_CMD_PING;
2131 		}
2132 	}
2133 
2134 	return bytes_read ? (int)bytes_read : err;
2135 }
2136 
2137 int evlist__ctlfd_ack(struct evlist *evlist)
2138 {
2139 	int err;
2140 
2141 	if (evlist->ctl_fd.ack == -1)
2142 		return 0;
2143 
2144 	err = write(evlist->ctl_fd.ack, EVLIST_CTL_CMD_ACK_TAG,
2145 		    sizeof(EVLIST_CTL_CMD_ACK_TAG));
2146 	if (err == -1)
2147 		pr_err("failed to write to ctl_ack_fd %d: %m\n", evlist->ctl_fd.ack);
2148 
2149 	return err;
2150 }
2151 
2152 static int get_cmd_arg(char *cmd_data, size_t cmd_size, char **arg)
2153 {
2154 	char *data = cmd_data + cmd_size;
2155 
2156 	/* no argument */
2157 	if (!*data)
2158 		return 0;
2159 
2160 	/* there's argument */
2161 	if (*data == ' ') {
2162 		*arg = data + 1;
2163 		return 1;
2164 	}
2165 
2166 	/* malformed */
2167 	return -1;
2168 }
2169 
2170 static int evlist__ctlfd_enable(struct evlist *evlist, char *cmd_data, bool enable)
2171 {
2172 	struct evsel *evsel;
2173 	char *name;
2174 	int err;
2175 
2176 	err = get_cmd_arg(cmd_data,
2177 			  enable ? sizeof(EVLIST_CTL_CMD_ENABLE_TAG) - 1 :
2178 				   sizeof(EVLIST_CTL_CMD_DISABLE_TAG) - 1,
2179 			  &name);
2180 	if (err < 0) {
2181 		pr_info("failed: wrong command\n");
2182 		return -1;
2183 	}
2184 
2185 	if (err) {
2186 		evsel = evlist__find_evsel_by_str(evlist, name);
2187 		if (evsel) {
2188 			if (enable)
2189 				evlist__enable_evsel(evlist, name);
2190 			else
2191 				evlist__disable_evsel(evlist, name);
2192 			pr_info("Event %s %s\n", evsel->name,
2193 				enable ? "enabled" : "disabled");
2194 		} else {
2195 			pr_info("failed: can't find '%s' event\n", name);
2196 		}
2197 	} else {
2198 		if (enable) {
2199 			evlist__enable(evlist);
2200 			pr_info(EVLIST_ENABLED_MSG);
2201 		} else {
2202 			evlist__disable(evlist);
2203 			pr_info(EVLIST_DISABLED_MSG);
2204 		}
2205 	}
2206 
2207 	return 0;
2208 }
2209 
2210 static int evlist__ctlfd_list(struct evlist *evlist, char *cmd_data)
2211 {
2212 	struct perf_attr_details details = { .verbose = false, };
2213 	struct evsel *evsel;
2214 	char *arg;
2215 	int err;
2216 
2217 	err = get_cmd_arg(cmd_data,
2218 			  sizeof(EVLIST_CTL_CMD_EVLIST_TAG) - 1,
2219 			  &arg);
2220 	if (err < 0) {
2221 		pr_info("failed: wrong command\n");
2222 		return -1;
2223 	}
2224 
2225 	if (err) {
2226 		if (!strcmp(arg, "-v")) {
2227 			details.verbose = true;
2228 		} else if (!strcmp(arg, "-g")) {
2229 			details.event_group = true;
2230 		} else if (!strcmp(arg, "-F")) {
2231 			details.freq = true;
2232 		} else {
2233 			pr_info("failed: wrong command\n");
2234 			return -1;
2235 		}
2236 	}
2237 
2238 	evlist__for_each_entry(evlist, evsel)
2239 		evsel__fprintf(evsel, &details, stderr);
2240 
2241 	return 0;
2242 }
2243 
2244 int evlist__ctlfd_process(struct evlist *evlist, enum evlist_ctl_cmd *cmd)
2245 {
2246 	int err = 0;
2247 	char cmd_data[EVLIST_CTL_CMD_MAX_LEN];
2248 	int ctlfd_pos = evlist->ctl_fd.pos;
2249 	struct pollfd *entries = evlist->core.pollfd.entries;
2250 
2251 	if (!evlist__ctlfd_initialized(evlist) || !entries[ctlfd_pos].revents)
2252 		return 0;
2253 
2254 	if (entries[ctlfd_pos].revents & POLLIN) {
2255 		err = evlist__ctlfd_recv(evlist, cmd, cmd_data,
2256 					 EVLIST_CTL_CMD_MAX_LEN);
2257 		if (err > 0) {
2258 			switch (*cmd) {
2259 			case EVLIST_CTL_CMD_ENABLE:
2260 			case EVLIST_CTL_CMD_DISABLE:
2261 				err = evlist__ctlfd_enable(evlist, cmd_data,
2262 							   *cmd == EVLIST_CTL_CMD_ENABLE);
2263 				break;
2264 			case EVLIST_CTL_CMD_EVLIST:
2265 				err = evlist__ctlfd_list(evlist, cmd_data);
2266 				break;
2267 			case EVLIST_CTL_CMD_SNAPSHOT:
2268 			case EVLIST_CTL_CMD_STOP:
2269 			case EVLIST_CTL_CMD_PING:
2270 				break;
2271 			case EVLIST_CTL_CMD_ACK:
2272 			case EVLIST_CTL_CMD_UNSUPPORTED:
2273 			default:
2274 				pr_debug("ctlfd: unsupported %d\n", *cmd);
2275 				break;
2276 			}
2277 			if (!(*cmd == EVLIST_CTL_CMD_ACK || *cmd == EVLIST_CTL_CMD_UNSUPPORTED ||
2278 			      *cmd == EVLIST_CTL_CMD_SNAPSHOT))
2279 				evlist__ctlfd_ack(evlist);
2280 		}
2281 	}
2282 
2283 	if (entries[ctlfd_pos].revents & (POLLHUP | POLLERR))
2284 		evlist__finalize_ctlfd(evlist);
2285 	else
2286 		entries[ctlfd_pos].revents = 0;
2287 
2288 	return err;
2289 }
2290 
2291 /**
2292  * struct event_enable_time - perf record -D/--delay single time range.
2293  * @start: start of time range to enable events in milliseconds
2294  * @end: end of time range to enable events in milliseconds
2295  *
2296  * N.B. this structure is also accessed as an array of int.
2297  */
2298 struct event_enable_time {
2299 	int	start;
2300 	int	end;
2301 };
2302 
2303 static int parse_event_enable_time(const char *str, struct event_enable_time *range, bool first)
2304 {
2305 	const char *fmt = first ? "%u - %u %n" : " , %u - %u %n";
2306 	int ret, start, end, n;
2307 
2308 	ret = sscanf(str, fmt, &start, &end, &n);
2309 	if (ret != 2 || end <= start)
2310 		return -EINVAL;
2311 	if (range) {
2312 		range->start = start;
2313 		range->end = end;
2314 	}
2315 	return n;
2316 }
2317 
2318 static ssize_t parse_event_enable_times(const char *str, struct event_enable_time *range)
2319 {
2320 	int incr = !!range;
2321 	bool first = true;
2322 	ssize_t ret, cnt;
2323 
2324 	for (cnt = 0; *str; cnt++) {
2325 		ret = parse_event_enable_time(str, range, first);
2326 		if (ret < 0)
2327 			return ret;
2328 		/* Check no overlap */
2329 		if (!first && range && range->start <= range[-1].end)
2330 			return -EINVAL;
2331 		str += ret;
2332 		range += incr;
2333 		first = false;
2334 	}
2335 	return cnt;
2336 }
2337 
2338 /**
2339  * struct event_enable_timer - control structure for perf record -D/--delay.
2340  * @evlist: event list
2341  * @times: time ranges that events are enabled (N.B. this is also accessed as an
2342  *         array of int)
2343  * @times_cnt: number of time ranges
2344  * @timerfd: timer file descriptor
2345  * @pollfd_pos: position in @evlist array of file descriptors to poll (fdarray)
2346  * @times_step: current position in (int *)@times)[],
2347  *              refer event_enable_timer__process()
2348  *
2349  * Note, this structure is only used when there are time ranges, not when there
2350  * is only an initial delay.
2351  */
2352 struct event_enable_timer {
2353 	struct evlist *evlist;
2354 	struct event_enable_time *times;
2355 	size_t	times_cnt;
2356 	int	timerfd;
2357 	int	pollfd_pos;
2358 	size_t	times_step;
2359 };
2360 
2361 static int str_to_delay(const char *str)
2362 {
2363 	char *endptr;
2364 	long d;
2365 
2366 	d = strtol(str, &endptr, 10);
2367 	if (*endptr || d > INT_MAX || d < -1)
2368 		return 0;
2369 	return d;
2370 }
2371 
2372 int evlist__parse_event_enable_time(struct evlist *evlist, struct record_opts *opts,
2373 				    const char *str, int unset)
2374 {
2375 	enum fdarray_flags flags = fdarray_flag__nonfilterable | fdarray_flag__non_perf_event;
2376 	struct event_enable_timer *eet;
2377 	ssize_t times_cnt;
2378 	ssize_t ret;
2379 	int err;
2380 
2381 	if (unset)
2382 		return 0;
2383 
2384 	opts->target.initial_delay = str_to_delay(str);
2385 	if (opts->target.initial_delay)
2386 		return 0;
2387 
2388 	ret = parse_event_enable_times(str, NULL);
2389 	if (ret < 0)
2390 		return ret;
2391 
2392 	times_cnt = ret;
2393 	if (times_cnt == 0)
2394 		return -EINVAL;
2395 
2396 	eet = zalloc(sizeof(*eet));
2397 	if (!eet)
2398 		return -ENOMEM;
2399 
2400 	eet->times = calloc(times_cnt, sizeof(*eet->times));
2401 	if (!eet->times) {
2402 		err = -ENOMEM;
2403 		goto free_eet;
2404 	}
2405 
2406 	if (parse_event_enable_times(str, eet->times) != times_cnt) {
2407 		err = -EINVAL;
2408 		goto free_eet_times;
2409 	}
2410 
2411 	eet->times_cnt = times_cnt;
2412 
2413 	eet->timerfd = timerfd_create(CLOCK_MONOTONIC, TFD_CLOEXEC);
2414 	if (eet->timerfd == -1) {
2415 		err = -errno;
2416 		pr_err("timerfd_create failed: %m\n");
2417 		goto free_eet_times;
2418 	}
2419 
2420 	eet->pollfd_pos = perf_evlist__add_pollfd(&evlist->core, eet->timerfd, NULL, POLLIN, flags);
2421 	if (eet->pollfd_pos < 0) {
2422 		err = eet->pollfd_pos;
2423 		goto close_timerfd;
2424 	}
2425 
2426 	eet->evlist = evlist;
2427 	evlist->eet = eet;
2428 	opts->target.initial_delay = eet->times[0].start;
2429 
2430 	return 0;
2431 
2432 close_timerfd:
2433 	close(eet->timerfd);
2434 free_eet_times:
2435 	zfree(&eet->times);
2436 free_eet:
2437 	free(eet);
2438 	return err;
2439 }
2440 
2441 static int event_enable_timer__set_timer(struct event_enable_timer *eet, int ms)
2442 {
2443 	struct itimerspec its = {
2444 		.it_value.tv_sec = ms / MSEC_PER_SEC,
2445 		.it_value.tv_nsec = (ms % MSEC_PER_SEC) * NSEC_PER_MSEC,
2446 	};
2447 	int err = 0;
2448 
2449 	if (timerfd_settime(eet->timerfd, 0, &its, NULL) < 0) {
2450 		err = -errno;
2451 		pr_err("timerfd_settime failed: %m\n");
2452 	}
2453 	return err;
2454 }
2455 
2456 int event_enable_timer__start(struct event_enable_timer *eet)
2457 {
2458 	int ms;
2459 
2460 	if (!eet)
2461 		return 0;
2462 
2463 	ms = eet->times[0].end - eet->times[0].start;
2464 	eet->times_step = 1;
2465 
2466 	return event_enable_timer__set_timer(eet, ms);
2467 }
2468 
2469 int event_enable_timer__process(struct event_enable_timer *eet)
2470 {
2471 	struct pollfd *entries;
2472 	short revents;
2473 
2474 	if (!eet)
2475 		return 0;
2476 
2477 	entries = eet->evlist->core.pollfd.entries;
2478 	revents = entries[eet->pollfd_pos].revents;
2479 	entries[eet->pollfd_pos].revents = 0;
2480 
2481 	if (revents & POLLIN) {
2482 		size_t step = eet->times_step;
2483 		size_t pos = step / 2;
2484 
2485 		if (step & 1) {
2486 			evlist__disable_non_dummy(eet->evlist);
2487 			pr_info(EVLIST_DISABLED_MSG);
2488 			if (pos >= eet->times_cnt - 1) {
2489 				/* Disarm timer */
2490 				event_enable_timer__set_timer(eet, 0);
2491 				return 1; /* Stop */
2492 			}
2493 		} else {
2494 			evlist__enable_non_dummy(eet->evlist);
2495 			pr_info(EVLIST_ENABLED_MSG);
2496 		}
2497 
2498 		step += 1;
2499 		pos = step / 2;
2500 
2501 		if (pos < eet->times_cnt) {
2502 			int *times = (int *)eet->times; /* Accessing 'times' as array of int */
2503 			int ms = times[step] - times[step - 1];
2504 
2505 			eet->times_step = step;
2506 			return event_enable_timer__set_timer(eet, ms);
2507 		}
2508 	}
2509 
2510 	return 0;
2511 }
2512 
2513 void event_enable_timer__exit(struct event_enable_timer **ep)
2514 {
2515 	if (!ep || !*ep)
2516 		return;
2517 	zfree(&(*ep)->times);
2518 	zfree(ep);
2519 }
2520 
2521 struct evsel *evlist__find_evsel(struct evlist *evlist, int idx)
2522 {
2523 	struct evsel *evsel;
2524 
2525 	evlist__for_each_entry(evlist, evsel) {
2526 		if (evsel->core.idx == idx)
2527 			return evsel;
2528 	}
2529 	return NULL;
2530 }
2531 
2532 void evlist__format_evsels(struct evlist *evlist, struct strbuf *sb, size_t max_length)
2533 {
2534 	struct evsel *evsel, *leader = NULL;
2535 	bool first = true;
2536 
2537 	evlist__for_each_entry(evlist, evsel) {
2538 		struct evsel *new_leader = evsel__leader(evsel);
2539 
2540 		if (evsel__is_dummy_event(evsel))
2541 			continue;
2542 
2543 		if (leader != new_leader && leader && leader->core.nr_members > 1)
2544 			strbuf_addch(sb, '}');
2545 
2546 		if (!first)
2547 			strbuf_addch(sb, ',');
2548 
2549 		if (sb->len > max_length) {
2550 			strbuf_addstr(sb, "...");
2551 			return;
2552 		}
2553 		if (leader != new_leader && new_leader->core.nr_members > 1)
2554 			strbuf_addch(sb, '{');
2555 
2556 		strbuf_addstr(sb, evsel__name(evsel));
2557 		first = false;
2558 		leader = new_leader;
2559 	}
2560 	if (leader && leader->core.nr_members > 1)
2561 		strbuf_addch(sb, '}');
2562 }
2563 
2564 void evlist__check_mem_load_aux(struct evlist *evlist)
2565 {
2566 	struct evsel *leader, *evsel, *pos;
2567 
2568 	/*
2569 	 * For some platforms, the 'mem-loads' event is required to use
2570 	 * together with 'mem-loads-aux' within a group and 'mem-loads-aux'
2571 	 * must be the group leader. Now we disable this group before reporting
2572 	 * because 'mem-loads-aux' is just an auxiliary event. It doesn't carry
2573 	 * any valid memory load information.
2574 	 */
2575 	evlist__for_each_entry(evlist, evsel) {
2576 		leader = evsel__leader(evsel);
2577 		if (leader == evsel)
2578 			continue;
2579 
2580 		if (leader->name && strstr(leader->name, "mem-loads-aux")) {
2581 			for_each_group_evsel(pos, leader) {
2582 				evsel__set_leader(pos, pos);
2583 				pos->core.nr_members = 0;
2584 			}
2585 		}
2586 	}
2587 }
2588 
2589 /**
2590  * evlist__warn_user_requested_cpus() - Check each evsel against requested CPUs
2591  *     and warn if the user CPU list is inapplicable for the event's PMU's
2592  *     CPUs. Not core PMUs list a CPU in sysfs, but this may be overwritten by a
2593  *     user requested CPU and so any online CPU is applicable. Core PMUs handle
2594  *     events on the CPUs in their list and otherwise the event isn't supported.
2595  * @evlist: The list of events being checked.
2596  * @cpu_list: The user provided list of CPUs.
2597  */
2598 void evlist__warn_user_requested_cpus(struct evlist *evlist, const char *cpu_list)
2599 {
2600 	struct perf_cpu_map *user_requested_cpus;
2601 	struct evsel *pos;
2602 
2603 	if (!cpu_list)
2604 		return;
2605 
2606 	user_requested_cpus = perf_cpu_map__new(cpu_list);
2607 	if (!user_requested_cpus)
2608 		return;
2609 
2610 	evlist__for_each_entry(evlist, pos) {
2611 		evsel__warn_user_requested_cpus(pos, user_requested_cpus);
2612 	}
2613 	perf_cpu_map__put(user_requested_cpus);
2614 }
2615 
2616 /* Should uniquify be disabled for the evlist? */
2617 static bool evlist__disable_uniquify(const struct evlist *evlist)
2618 {
2619 	struct evsel *counter;
2620 	struct perf_pmu *last_pmu = NULL;
2621 	bool first = true;
2622 
2623 	evlist__for_each_entry(evlist, counter) {
2624 		/* If PMUs vary then uniquify can be useful. */
2625 		if (!first && counter->pmu != last_pmu)
2626 			return false;
2627 		first = false;
2628 		if (counter->pmu) {
2629 			/* Allow uniquify for uncore PMUs. */
2630 			if (!counter->pmu->is_core)
2631 				return false;
2632 			/* Keep hybrid event names uniquified for clarity. */
2633 			if (perf_pmus__num_core_pmus() > 1)
2634 				return false;
2635 		}
2636 		last_pmu = counter->pmu;
2637 	}
2638 	return true;
2639 }
2640 
2641 static bool evlist__set_needs_uniquify(struct evlist *evlist, const struct perf_stat_config *config)
2642 {
2643 	struct evsel *counter;
2644 	bool needs_uniquify = false;
2645 
2646 	if (evlist__disable_uniquify(evlist)) {
2647 		evlist__for_each_entry(evlist, counter)
2648 			counter->uniquified_name = true;
2649 		return false;
2650 	}
2651 
2652 	evlist__for_each_entry(evlist, counter) {
2653 		if (evsel__set_needs_uniquify(counter, config))
2654 			needs_uniquify = true;
2655 	}
2656 	return needs_uniquify;
2657 }
2658 
2659 void evlist__uniquify_evsel_names(struct evlist *evlist, const struct perf_stat_config *config)
2660 {
2661 	if (evlist__set_needs_uniquify(evlist, config)) {
2662 		struct evsel *pos;
2663 
2664 		evlist__for_each_entry(evlist, pos)
2665 			evsel__uniquify_counter(pos);
2666 	}
2667 }
2668 
2669 bool evlist__has_bpf_output(struct evlist *evlist)
2670 {
2671 	struct evsel *evsel;
2672 
2673 	evlist__for_each_entry(evlist, evsel) {
2674 		if (evsel__is_bpf_output(evsel))
2675 			return true;
2676 	}
2677 
2678 	return false;
2679 }
2680 
2681 bool evlist__needs_bpf_sb_event(struct evlist *evlist)
2682 {
2683 	struct evsel *evsel;
2684 
2685 	evlist__for_each_entry(evlist, evsel) {
2686 		if (evsel__is_dummy_event(evsel))
2687 			continue;
2688 		if (!evsel->core.attr.exclude_kernel)
2689 			return true;
2690 	}
2691 
2692 	return false;
2693 }
2694