xref: /linux/tools/perf/util/evlist.c (revision 058443934524590d5537a80f490267cc95a61c05)
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 "evlist.h"
17 #include "evsel.h"
18 #include "record.h"
19 #include "debug.h"
20 #include "units.h"
21 #include "bpf_counter.h"
22 #include <internal/lib.h> // page_size
23 #include "affinity.h"
24 #include "../perf.h"
25 #include "asm/bug.h"
26 #include "bpf-event.h"
27 #include "util/string2.h"
28 #include "util/perf_api_probe.h"
29 #include "util/evsel_fprintf.h"
30 #include "util/evlist-hybrid.h"
31 #include "util/pmu.h"
32 #include <signal.h>
33 #include <unistd.h>
34 #include <sched.h>
35 #include <stdlib.h>
36 
37 #include "parse-events.h"
38 #include <subcmd/parse-options.h>
39 
40 #include <fcntl.h>
41 #include <sys/ioctl.h>
42 #include <sys/mman.h>
43 #include <sys/prctl.h>
44 #include <sys/timerfd.h>
45 
46 #include <linux/bitops.h>
47 #include <linux/hash.h>
48 #include <linux/log2.h>
49 #include <linux/err.h>
50 #include <linux/string.h>
51 #include <linux/time64.h>
52 #include <linux/zalloc.h>
53 #include <perf/evlist.h>
54 #include <perf/evsel.h>
55 #include <perf/cpumap.h>
56 #include <perf/mmap.h>
57 
58 #include <internal/xyarray.h>
59 
60 #ifdef LACKS_SIGQUEUE_PROTOTYPE
61 int sigqueue(pid_t pid, int sig, const union sigval value);
62 #endif
63 
64 #define FD(e, x, y) (*(int *)xyarray__entry(e->core.fd, x, y))
65 #define SID(e, x, y) xyarray__entry(e->core.sample_id, x, y)
66 
67 void evlist__init(struct evlist *evlist, struct perf_cpu_map *cpus,
68 		  struct perf_thread_map *threads)
69 {
70 	perf_evlist__init(&evlist->core);
71 	perf_evlist__set_maps(&evlist->core, cpus, threads);
72 	evlist->workload.pid = -1;
73 	evlist->bkw_mmap_state = BKW_MMAP_NOTREADY;
74 	evlist->ctl_fd.fd = -1;
75 	evlist->ctl_fd.ack = -1;
76 	evlist->ctl_fd.pos = -1;
77 }
78 
79 struct evlist *evlist__new(void)
80 {
81 	struct evlist *evlist = zalloc(sizeof(*evlist));
82 
83 	if (evlist != NULL)
84 		evlist__init(evlist, NULL, NULL);
85 
86 	return evlist;
87 }
88 
89 struct evlist *evlist__new_default(void)
90 {
91 	struct evlist *evlist = evlist__new();
92 
93 	if (evlist && evlist__add_default(evlist)) {
94 		evlist__delete(evlist);
95 		evlist = NULL;
96 	}
97 
98 	return evlist;
99 }
100 
101 struct evlist *evlist__new_dummy(void)
102 {
103 	struct evlist *evlist = evlist__new();
104 
105 	if (evlist && evlist__add_dummy(evlist)) {
106 		evlist__delete(evlist);
107 		evlist = NULL;
108 	}
109 
110 	return evlist;
111 }
112 
113 /**
114  * evlist__set_id_pos - set the positions of event ids.
115  * @evlist: selected event list
116  *
117  * Events with compatible sample types all have the same id_pos
118  * and is_pos.  For convenience, put a copy on evlist.
119  */
120 void evlist__set_id_pos(struct evlist *evlist)
121 {
122 	struct evsel *first = evlist__first(evlist);
123 
124 	evlist->id_pos = first->id_pos;
125 	evlist->is_pos = first->is_pos;
126 }
127 
128 static void evlist__update_id_pos(struct evlist *evlist)
129 {
130 	struct evsel *evsel;
131 
132 	evlist__for_each_entry(evlist, evsel)
133 		evsel__calc_id_pos(evsel);
134 
135 	evlist__set_id_pos(evlist);
136 }
137 
138 static void evlist__purge(struct evlist *evlist)
139 {
140 	struct evsel *pos, *n;
141 
142 	evlist__for_each_entry_safe(evlist, n, pos) {
143 		list_del_init(&pos->core.node);
144 		pos->evlist = NULL;
145 		evsel__delete(pos);
146 	}
147 
148 	evlist->core.nr_entries = 0;
149 }
150 
151 void evlist__exit(struct evlist *evlist)
152 {
153 	event_enable_timer__exit(&evlist->eet);
154 	zfree(&evlist->mmap);
155 	zfree(&evlist->overwrite_mmap);
156 	perf_evlist__exit(&evlist->core);
157 }
158 
159 void evlist__delete(struct evlist *evlist)
160 {
161 	if (evlist == NULL)
162 		return;
163 
164 	evlist__munmap(evlist);
165 	evlist__close(evlist);
166 	evlist__purge(evlist);
167 	evlist__exit(evlist);
168 	free(evlist);
169 }
170 
171 void evlist__add(struct evlist *evlist, struct evsel *entry)
172 {
173 	perf_evlist__add(&evlist->core, &entry->core);
174 	entry->evlist = evlist;
175 	entry->tracking = !entry->core.idx;
176 
177 	if (evlist->core.nr_entries == 1)
178 		evlist__set_id_pos(evlist);
179 }
180 
181 void evlist__remove(struct evlist *evlist, struct evsel *evsel)
182 {
183 	evsel->evlist = NULL;
184 	perf_evlist__remove(&evlist->core, &evsel->core);
185 }
186 
187 void evlist__splice_list_tail(struct evlist *evlist, struct list_head *list)
188 {
189 	while (!list_empty(list)) {
190 		struct evsel *evsel, *temp, *leader = NULL;
191 
192 		__evlist__for_each_entry_safe(list, temp, evsel) {
193 			list_del_init(&evsel->core.node);
194 			evlist__add(evlist, evsel);
195 			leader = evsel;
196 			break;
197 		}
198 
199 		__evlist__for_each_entry_safe(list, temp, evsel) {
200 			if (evsel__has_leader(evsel, leader)) {
201 				list_del_init(&evsel->core.node);
202 				evlist__add(evlist, evsel);
203 			}
204 		}
205 	}
206 }
207 
208 int __evlist__set_tracepoints_handlers(struct evlist *evlist,
209 				       const struct evsel_str_handler *assocs, size_t nr_assocs)
210 {
211 	size_t i;
212 	int err;
213 
214 	for (i = 0; i < nr_assocs; i++) {
215 		// Adding a handler for an event not in this evlist, just ignore it.
216 		struct evsel *evsel = evlist__find_tracepoint_by_name(evlist, assocs[i].name);
217 		if (evsel == NULL)
218 			continue;
219 
220 		err = -EEXIST;
221 		if (evsel->handler != NULL)
222 			goto out;
223 		evsel->handler = assocs[i].handler;
224 	}
225 
226 	err = 0;
227 out:
228 	return err;
229 }
230 
231 void evlist__set_leader(struct evlist *evlist)
232 {
233 	perf_evlist__set_leader(&evlist->core);
234 }
235 
236 int __evlist__add_default(struct evlist *evlist, bool precise)
237 {
238 	struct evsel *evsel;
239 
240 	evsel = evsel__new_cycles(precise, PERF_TYPE_HARDWARE,
241 				  PERF_COUNT_HW_CPU_CYCLES);
242 	if (evsel == NULL)
243 		return -ENOMEM;
244 
245 	evlist__add(evlist, evsel);
246 	return 0;
247 }
248 
249 static struct evsel *evlist__dummy_event(struct evlist *evlist)
250 {
251 	struct perf_event_attr attr = {
252 		.type	= PERF_TYPE_SOFTWARE,
253 		.config = PERF_COUNT_SW_DUMMY,
254 		.size	= sizeof(attr), /* to capture ABI version */
255 	};
256 
257 	return evsel__new_idx(&attr, evlist->core.nr_entries);
258 }
259 
260 int evlist__add_dummy(struct evlist *evlist)
261 {
262 	struct evsel *evsel = evlist__dummy_event(evlist);
263 
264 	if (evsel == NULL)
265 		return -ENOMEM;
266 
267 	evlist__add(evlist, evsel);
268 	return 0;
269 }
270 
271 static void evlist__add_on_all_cpus(struct evlist *evlist, struct evsel *evsel)
272 {
273 	evsel->core.system_wide = true;
274 
275 	/*
276 	 * All CPUs.
277 	 *
278 	 * Note perf_event_open() does not accept CPUs that are not online, so
279 	 * in fact this CPU list will include only all online CPUs.
280 	 */
281 	perf_cpu_map__put(evsel->core.own_cpus);
282 	evsel->core.own_cpus = perf_cpu_map__new(NULL);
283 	perf_cpu_map__put(evsel->core.cpus);
284 	evsel->core.cpus = perf_cpu_map__get(evsel->core.own_cpus);
285 
286 	/* No threads */
287 	perf_thread_map__put(evsel->core.threads);
288 	evsel->core.threads = perf_thread_map__new_dummy();
289 
290 	evlist__add(evlist, evsel);
291 }
292 
293 struct evsel *evlist__add_aux_dummy(struct evlist *evlist, bool system_wide)
294 {
295 	struct evsel *evsel = evlist__dummy_event(evlist);
296 
297 	if (!evsel)
298 		return NULL;
299 
300 	evsel->core.attr.exclude_kernel = 1;
301 	evsel->core.attr.exclude_guest = 1;
302 	evsel->core.attr.exclude_hv = 1;
303 	evsel->core.attr.freq = 0;
304 	evsel->core.attr.sample_period = 1;
305 	evsel->no_aux_samples = true;
306 	evsel->name = strdup("dummy:u");
307 
308 	if (system_wide)
309 		evlist__add_on_all_cpus(evlist, evsel);
310 	else
311 		evlist__add(evlist, evsel);
312 
313 	return evsel;
314 }
315 
316 int evlist__add_attrs(struct evlist *evlist, struct perf_event_attr *attrs, size_t nr_attrs)
317 {
318 	struct evsel *evsel, *n;
319 	LIST_HEAD(head);
320 	size_t i;
321 
322 	for (i = 0; i < nr_attrs; i++) {
323 		evsel = evsel__new_idx(attrs + i, evlist->core.nr_entries + i);
324 		if (evsel == NULL)
325 			goto out_delete_partial_list;
326 		list_add_tail(&evsel->core.node, &head);
327 	}
328 
329 	evlist__splice_list_tail(evlist, &head);
330 
331 	return 0;
332 
333 out_delete_partial_list:
334 	__evlist__for_each_entry_safe(&head, n, evsel)
335 		evsel__delete(evsel);
336 	return -1;
337 }
338 
339 int __evlist__add_default_attrs(struct evlist *evlist, struct perf_event_attr *attrs, size_t nr_attrs)
340 {
341 	size_t i;
342 
343 	for (i = 0; i < nr_attrs; i++)
344 		event_attr_init(attrs + i);
345 
346 	return evlist__add_attrs(evlist, attrs, nr_attrs);
347 }
348 
349 __weak int arch_evlist__add_default_attrs(struct evlist *evlist,
350 					  struct perf_event_attr *attrs,
351 					  size_t nr_attrs)
352 {
353 	if (!nr_attrs)
354 		return 0;
355 
356 	return __evlist__add_default_attrs(evlist, attrs, nr_attrs);
357 }
358 
359 struct evsel *evlist__find_tracepoint_by_id(struct evlist *evlist, int id)
360 {
361 	struct evsel *evsel;
362 
363 	evlist__for_each_entry(evlist, evsel) {
364 		if (evsel->core.attr.type   == PERF_TYPE_TRACEPOINT &&
365 		    (int)evsel->core.attr.config == id)
366 			return evsel;
367 	}
368 
369 	return NULL;
370 }
371 
372 struct evsel *evlist__find_tracepoint_by_name(struct evlist *evlist, const char *name)
373 {
374 	struct evsel *evsel;
375 
376 	evlist__for_each_entry(evlist, evsel) {
377 		if ((evsel->core.attr.type == PERF_TYPE_TRACEPOINT) &&
378 		    (strcmp(evsel->name, name) == 0))
379 			return evsel;
380 	}
381 
382 	return NULL;
383 }
384 
385 int evlist__add_newtp(struct evlist *evlist, const char *sys, const char *name, void *handler)
386 {
387 	struct evsel *evsel = evsel__newtp(sys, name);
388 
389 	if (IS_ERR(evsel))
390 		return -1;
391 
392 	evsel->handler = handler;
393 	evlist__add(evlist, evsel);
394 	return 0;
395 }
396 
397 struct evlist_cpu_iterator evlist__cpu_begin(struct evlist *evlist, struct affinity *affinity)
398 {
399 	struct evlist_cpu_iterator itr = {
400 		.container = evlist,
401 		.evsel = NULL,
402 		.cpu_map_idx = 0,
403 		.evlist_cpu_map_idx = 0,
404 		.evlist_cpu_map_nr = perf_cpu_map__nr(evlist->core.all_cpus),
405 		.cpu = (struct perf_cpu){ .cpu = -1},
406 		.affinity = affinity,
407 	};
408 
409 	if (evlist__empty(evlist)) {
410 		/* Ensure the empty list doesn't iterate. */
411 		itr.evlist_cpu_map_idx = itr.evlist_cpu_map_nr;
412 	} else {
413 		itr.evsel = evlist__first(evlist);
414 		if (itr.affinity) {
415 			itr.cpu = perf_cpu_map__cpu(evlist->core.all_cpus, 0);
416 			affinity__set(itr.affinity, itr.cpu.cpu);
417 			itr.cpu_map_idx = perf_cpu_map__idx(itr.evsel->core.cpus, itr.cpu);
418 			/*
419 			 * If this CPU isn't in the evsel's cpu map then advance
420 			 * through the list.
421 			 */
422 			if (itr.cpu_map_idx == -1)
423 				evlist_cpu_iterator__next(&itr);
424 		}
425 	}
426 	return itr;
427 }
428 
429 void evlist_cpu_iterator__next(struct evlist_cpu_iterator *evlist_cpu_itr)
430 {
431 	while (evlist_cpu_itr->evsel != evlist__last(evlist_cpu_itr->container)) {
432 		evlist_cpu_itr->evsel = evsel__next(evlist_cpu_itr->evsel);
433 		evlist_cpu_itr->cpu_map_idx =
434 			perf_cpu_map__idx(evlist_cpu_itr->evsel->core.cpus,
435 					  evlist_cpu_itr->cpu);
436 		if (evlist_cpu_itr->cpu_map_idx != -1)
437 			return;
438 	}
439 	evlist_cpu_itr->evlist_cpu_map_idx++;
440 	if (evlist_cpu_itr->evlist_cpu_map_idx < evlist_cpu_itr->evlist_cpu_map_nr) {
441 		evlist_cpu_itr->evsel = evlist__first(evlist_cpu_itr->container);
442 		evlist_cpu_itr->cpu =
443 			perf_cpu_map__cpu(evlist_cpu_itr->container->core.all_cpus,
444 					  evlist_cpu_itr->evlist_cpu_map_idx);
445 		if (evlist_cpu_itr->affinity)
446 			affinity__set(evlist_cpu_itr->affinity, evlist_cpu_itr->cpu.cpu);
447 		evlist_cpu_itr->cpu_map_idx =
448 			perf_cpu_map__idx(evlist_cpu_itr->evsel->core.cpus,
449 					  evlist_cpu_itr->cpu);
450 		/*
451 		 * If this CPU isn't in the evsel's cpu map then advance through
452 		 * the list.
453 		 */
454 		if (evlist_cpu_itr->cpu_map_idx == -1)
455 			evlist_cpu_iterator__next(evlist_cpu_itr);
456 	}
457 }
458 
459 bool evlist_cpu_iterator__end(const struct evlist_cpu_iterator *evlist_cpu_itr)
460 {
461 	return evlist_cpu_itr->evlist_cpu_map_idx >= evlist_cpu_itr->evlist_cpu_map_nr;
462 }
463 
464 static int evsel__strcmp(struct evsel *pos, char *evsel_name)
465 {
466 	if (!evsel_name)
467 		return 0;
468 	if (evsel__is_dummy_event(pos))
469 		return 1;
470 	return strcmp(pos->name, evsel_name);
471 }
472 
473 static int evlist__is_enabled(struct evlist *evlist)
474 {
475 	struct evsel *pos;
476 
477 	evlist__for_each_entry(evlist, pos) {
478 		if (!evsel__is_group_leader(pos) || !pos->core.fd)
479 			continue;
480 		/* If at least one event is enabled, evlist is enabled. */
481 		if (!pos->disabled)
482 			return true;
483 	}
484 	return false;
485 }
486 
487 static void __evlist__disable(struct evlist *evlist, char *evsel_name, bool excl_dummy)
488 {
489 	struct evsel *pos;
490 	struct evlist_cpu_iterator evlist_cpu_itr;
491 	struct affinity saved_affinity, *affinity = NULL;
492 	bool has_imm = false;
493 
494 	// See explanation in evlist__close()
495 	if (!cpu_map__is_dummy(evlist->core.user_requested_cpus)) {
496 		if (affinity__setup(&saved_affinity) < 0)
497 			return;
498 		affinity = &saved_affinity;
499 	}
500 
501 	/* Disable 'immediate' events last */
502 	for (int imm = 0; imm <= 1; imm++) {
503 		evlist__for_each_cpu(evlist_cpu_itr, evlist, affinity) {
504 			pos = evlist_cpu_itr.evsel;
505 			if (evsel__strcmp(pos, evsel_name))
506 				continue;
507 			if (pos->disabled || !evsel__is_group_leader(pos) || !pos->core.fd)
508 				continue;
509 			if (excl_dummy && evsel__is_dummy_event(pos))
510 				continue;
511 			if (pos->immediate)
512 				has_imm = true;
513 			if (pos->immediate != imm)
514 				continue;
515 			evsel__disable_cpu(pos, evlist_cpu_itr.cpu_map_idx);
516 		}
517 		if (!has_imm)
518 			break;
519 	}
520 
521 	affinity__cleanup(affinity);
522 	evlist__for_each_entry(evlist, pos) {
523 		if (evsel__strcmp(pos, evsel_name))
524 			continue;
525 		if (!evsel__is_group_leader(pos) || !pos->core.fd)
526 			continue;
527 		if (excl_dummy && evsel__is_dummy_event(pos))
528 			continue;
529 		pos->disabled = true;
530 	}
531 
532 	/*
533 	 * If we disabled only single event, we need to check
534 	 * the enabled state of the evlist manually.
535 	 */
536 	if (evsel_name)
537 		evlist->enabled = evlist__is_enabled(evlist);
538 	else
539 		evlist->enabled = false;
540 }
541 
542 void evlist__disable(struct evlist *evlist)
543 {
544 	__evlist__disable(evlist, NULL, false);
545 }
546 
547 void evlist__disable_non_dummy(struct evlist *evlist)
548 {
549 	__evlist__disable(evlist, NULL, true);
550 }
551 
552 void evlist__disable_evsel(struct evlist *evlist, char *evsel_name)
553 {
554 	__evlist__disable(evlist, evsel_name, false);
555 }
556 
557 static void __evlist__enable(struct evlist *evlist, char *evsel_name, bool excl_dummy)
558 {
559 	struct evsel *pos;
560 	struct evlist_cpu_iterator evlist_cpu_itr;
561 	struct affinity saved_affinity, *affinity = NULL;
562 
563 	// See explanation in evlist__close()
564 	if (!cpu_map__is_dummy(evlist->core.user_requested_cpus)) {
565 		if (affinity__setup(&saved_affinity) < 0)
566 			return;
567 		affinity = &saved_affinity;
568 	}
569 
570 	evlist__for_each_cpu(evlist_cpu_itr, evlist, affinity) {
571 		pos = evlist_cpu_itr.evsel;
572 		if (evsel__strcmp(pos, evsel_name))
573 			continue;
574 		if (!evsel__is_group_leader(pos) || !pos->core.fd)
575 			continue;
576 		if (excl_dummy && evsel__is_dummy_event(pos))
577 			continue;
578 		evsel__enable_cpu(pos, evlist_cpu_itr.cpu_map_idx);
579 	}
580 	affinity__cleanup(affinity);
581 	evlist__for_each_entry(evlist, pos) {
582 		if (evsel__strcmp(pos, evsel_name))
583 			continue;
584 		if (!evsel__is_group_leader(pos) || !pos->core.fd)
585 			continue;
586 		if (excl_dummy && evsel__is_dummy_event(pos))
587 			continue;
588 		pos->disabled = false;
589 	}
590 
591 	/*
592 	 * Even single event sets the 'enabled' for evlist,
593 	 * so the toggle can work properly and toggle to
594 	 * 'disabled' state.
595 	 */
596 	evlist->enabled = true;
597 }
598 
599 void evlist__enable(struct evlist *evlist)
600 {
601 	__evlist__enable(evlist, NULL, false);
602 }
603 
604 void evlist__enable_non_dummy(struct evlist *evlist)
605 {
606 	__evlist__enable(evlist, NULL, true);
607 }
608 
609 void evlist__enable_evsel(struct evlist *evlist, char *evsel_name)
610 {
611 	__evlist__enable(evlist, evsel_name, false);
612 }
613 
614 void evlist__toggle_enable(struct evlist *evlist)
615 {
616 	(evlist->enabled ? evlist__disable : evlist__enable)(evlist);
617 }
618 
619 int evlist__add_pollfd(struct evlist *evlist, int fd)
620 {
621 	return perf_evlist__add_pollfd(&evlist->core, fd, NULL, POLLIN, fdarray_flag__default);
622 }
623 
624 int evlist__filter_pollfd(struct evlist *evlist, short revents_and_mask)
625 {
626 	return perf_evlist__filter_pollfd(&evlist->core, revents_and_mask);
627 }
628 
629 #ifdef HAVE_EVENTFD_SUPPORT
630 int evlist__add_wakeup_eventfd(struct evlist *evlist, int fd)
631 {
632 	return perf_evlist__add_pollfd(&evlist->core, fd, NULL, POLLIN,
633 				       fdarray_flag__nonfilterable |
634 				       fdarray_flag__non_perf_event);
635 }
636 #endif
637 
638 int evlist__poll(struct evlist *evlist, int timeout)
639 {
640 	return perf_evlist__poll(&evlist->core, timeout);
641 }
642 
643 struct perf_sample_id *evlist__id2sid(struct evlist *evlist, u64 id)
644 {
645 	struct hlist_head *head;
646 	struct perf_sample_id *sid;
647 	int hash;
648 
649 	hash = hash_64(id, PERF_EVLIST__HLIST_BITS);
650 	head = &evlist->core.heads[hash];
651 
652 	hlist_for_each_entry(sid, head, node)
653 		if (sid->id == id)
654 			return sid;
655 
656 	return NULL;
657 }
658 
659 struct evsel *evlist__id2evsel(struct evlist *evlist, u64 id)
660 {
661 	struct perf_sample_id *sid;
662 
663 	if (evlist->core.nr_entries == 1 || !id)
664 		return evlist__first(evlist);
665 
666 	sid = evlist__id2sid(evlist, id);
667 	if (sid)
668 		return container_of(sid->evsel, struct evsel, core);
669 
670 	if (!evlist__sample_id_all(evlist))
671 		return evlist__first(evlist);
672 
673 	return NULL;
674 }
675 
676 struct evsel *evlist__id2evsel_strict(struct evlist *evlist, u64 id)
677 {
678 	struct perf_sample_id *sid;
679 
680 	if (!id)
681 		return NULL;
682 
683 	sid = evlist__id2sid(evlist, id);
684 	if (sid)
685 		return container_of(sid->evsel, struct evsel, core);
686 
687 	return NULL;
688 }
689 
690 static int evlist__event2id(struct evlist *evlist, union perf_event *event, u64 *id)
691 {
692 	const __u64 *array = event->sample.array;
693 	ssize_t n;
694 
695 	n = (event->header.size - sizeof(event->header)) >> 3;
696 
697 	if (event->header.type == PERF_RECORD_SAMPLE) {
698 		if (evlist->id_pos >= n)
699 			return -1;
700 		*id = array[evlist->id_pos];
701 	} else {
702 		if (evlist->is_pos > n)
703 			return -1;
704 		n -= evlist->is_pos;
705 		*id = array[n];
706 	}
707 	return 0;
708 }
709 
710 struct evsel *evlist__event2evsel(struct evlist *evlist, union perf_event *event)
711 {
712 	struct evsel *first = evlist__first(evlist);
713 	struct hlist_head *head;
714 	struct perf_sample_id *sid;
715 	int hash;
716 	u64 id;
717 
718 	if (evlist->core.nr_entries == 1)
719 		return first;
720 
721 	if (!first->core.attr.sample_id_all &&
722 	    event->header.type != PERF_RECORD_SAMPLE)
723 		return first;
724 
725 	if (evlist__event2id(evlist, event, &id))
726 		return NULL;
727 
728 	/* Synthesized events have an id of zero */
729 	if (!id)
730 		return first;
731 
732 	hash = hash_64(id, PERF_EVLIST__HLIST_BITS);
733 	head = &evlist->core.heads[hash];
734 
735 	hlist_for_each_entry(sid, head, node) {
736 		if (sid->id == id)
737 			return container_of(sid->evsel, struct evsel, core);
738 	}
739 	return NULL;
740 }
741 
742 static int evlist__set_paused(struct evlist *evlist, bool value)
743 {
744 	int i;
745 
746 	if (!evlist->overwrite_mmap)
747 		return 0;
748 
749 	for (i = 0; i < evlist->core.nr_mmaps; i++) {
750 		int fd = evlist->overwrite_mmap[i].core.fd;
751 		int err;
752 
753 		if (fd < 0)
754 			continue;
755 		err = ioctl(fd, PERF_EVENT_IOC_PAUSE_OUTPUT, value ? 1 : 0);
756 		if (err)
757 			return err;
758 	}
759 	return 0;
760 }
761 
762 static int evlist__pause(struct evlist *evlist)
763 {
764 	return evlist__set_paused(evlist, true);
765 }
766 
767 static int evlist__resume(struct evlist *evlist)
768 {
769 	return evlist__set_paused(evlist, false);
770 }
771 
772 static void evlist__munmap_nofree(struct evlist *evlist)
773 {
774 	int i;
775 
776 	if (evlist->mmap)
777 		for (i = 0; i < evlist->core.nr_mmaps; i++)
778 			perf_mmap__munmap(&evlist->mmap[i].core);
779 
780 	if (evlist->overwrite_mmap)
781 		for (i = 0; i < evlist->core.nr_mmaps; i++)
782 			perf_mmap__munmap(&evlist->overwrite_mmap[i].core);
783 }
784 
785 void evlist__munmap(struct evlist *evlist)
786 {
787 	evlist__munmap_nofree(evlist);
788 	zfree(&evlist->mmap);
789 	zfree(&evlist->overwrite_mmap);
790 }
791 
792 static void perf_mmap__unmap_cb(struct perf_mmap *map)
793 {
794 	struct mmap *m = container_of(map, struct mmap, core);
795 
796 	mmap__munmap(m);
797 }
798 
799 static struct mmap *evlist__alloc_mmap(struct evlist *evlist,
800 				       bool overwrite)
801 {
802 	int i;
803 	struct mmap *map;
804 
805 	map = zalloc(evlist->core.nr_mmaps * sizeof(struct mmap));
806 	if (!map)
807 		return NULL;
808 
809 	for (i = 0; i < evlist->core.nr_mmaps; i++) {
810 		struct perf_mmap *prev = i ? &map[i - 1].core : NULL;
811 
812 		/*
813 		 * When the perf_mmap() call is made we grab one refcount, plus
814 		 * one extra to let perf_mmap__consume() get the last
815 		 * events after all real references (perf_mmap__get()) are
816 		 * dropped.
817 		 *
818 		 * Each PERF_EVENT_IOC_SET_OUTPUT points to this mmap and
819 		 * thus does perf_mmap__get() on it.
820 		 */
821 		perf_mmap__init(&map[i].core, prev, overwrite, perf_mmap__unmap_cb);
822 	}
823 
824 	return map;
825 }
826 
827 static void
828 perf_evlist__mmap_cb_idx(struct perf_evlist *_evlist,
829 			 struct perf_evsel *_evsel,
830 			 struct perf_mmap_param *_mp,
831 			 int idx)
832 {
833 	struct evlist *evlist = container_of(_evlist, struct evlist, core);
834 	struct mmap_params *mp = container_of(_mp, struct mmap_params, core);
835 	struct evsel *evsel = container_of(_evsel, struct evsel, core);
836 
837 	auxtrace_mmap_params__set_idx(&mp->auxtrace_mp, evlist, evsel, idx);
838 }
839 
840 static struct perf_mmap*
841 perf_evlist__mmap_cb_get(struct perf_evlist *_evlist, bool overwrite, int idx)
842 {
843 	struct evlist *evlist = container_of(_evlist, struct evlist, core);
844 	struct mmap *maps;
845 
846 	maps = overwrite ? evlist->overwrite_mmap : evlist->mmap;
847 
848 	if (!maps) {
849 		maps = evlist__alloc_mmap(evlist, overwrite);
850 		if (!maps)
851 			return NULL;
852 
853 		if (overwrite) {
854 			evlist->overwrite_mmap = maps;
855 			if (evlist->bkw_mmap_state == BKW_MMAP_NOTREADY)
856 				evlist__toggle_bkw_mmap(evlist, BKW_MMAP_RUNNING);
857 		} else {
858 			evlist->mmap = maps;
859 		}
860 	}
861 
862 	return &maps[idx].core;
863 }
864 
865 static int
866 perf_evlist__mmap_cb_mmap(struct perf_mmap *_map, struct perf_mmap_param *_mp,
867 			  int output, struct perf_cpu cpu)
868 {
869 	struct mmap *map = container_of(_map, struct mmap, core);
870 	struct mmap_params *mp = container_of(_mp, struct mmap_params, core);
871 
872 	return mmap__mmap(map, mp, output, cpu);
873 }
874 
875 unsigned long perf_event_mlock_kb_in_pages(void)
876 {
877 	unsigned long pages;
878 	int max;
879 
880 	if (sysctl__read_int("kernel/perf_event_mlock_kb", &max) < 0) {
881 		/*
882 		 * Pick a once upon a time good value, i.e. things look
883 		 * strange since we can't read a sysctl value, but lets not
884 		 * die yet...
885 		 */
886 		max = 512;
887 	} else {
888 		max -= (page_size / 1024);
889 	}
890 
891 	pages = (max * 1024) / page_size;
892 	if (!is_power_of_2(pages))
893 		pages = rounddown_pow_of_two(pages);
894 
895 	return pages;
896 }
897 
898 size_t evlist__mmap_size(unsigned long pages)
899 {
900 	if (pages == UINT_MAX)
901 		pages = perf_event_mlock_kb_in_pages();
902 	else if (!is_power_of_2(pages))
903 		return 0;
904 
905 	return (pages + 1) * page_size;
906 }
907 
908 static long parse_pages_arg(const char *str, unsigned long min,
909 			    unsigned long max)
910 {
911 	unsigned long pages, val;
912 	static struct parse_tag tags[] = {
913 		{ .tag  = 'B', .mult = 1       },
914 		{ .tag  = 'K', .mult = 1 << 10 },
915 		{ .tag  = 'M', .mult = 1 << 20 },
916 		{ .tag  = 'G', .mult = 1 << 30 },
917 		{ .tag  = 0 },
918 	};
919 
920 	if (str == NULL)
921 		return -EINVAL;
922 
923 	val = parse_tag_value(str, tags);
924 	if (val != (unsigned long) -1) {
925 		/* we got file size value */
926 		pages = PERF_ALIGN(val, page_size) / page_size;
927 	} else {
928 		/* we got pages count value */
929 		char *eptr;
930 		pages = strtoul(str, &eptr, 10);
931 		if (*eptr != '\0')
932 			return -EINVAL;
933 	}
934 
935 	if (pages == 0 && min == 0) {
936 		/* leave number of pages at 0 */
937 	} else if (!is_power_of_2(pages)) {
938 		char buf[100];
939 
940 		/* round pages up to next power of 2 */
941 		pages = roundup_pow_of_two(pages);
942 		if (!pages)
943 			return -EINVAL;
944 
945 		unit_number__scnprintf(buf, sizeof(buf), pages * page_size);
946 		pr_info("rounding mmap pages size to %s (%lu pages)\n",
947 			buf, pages);
948 	}
949 
950 	if (pages > max)
951 		return -EINVAL;
952 
953 	return pages;
954 }
955 
956 int __evlist__parse_mmap_pages(unsigned int *mmap_pages, const char *str)
957 {
958 	unsigned long max = UINT_MAX;
959 	long pages;
960 
961 	if (max > SIZE_MAX / page_size)
962 		max = SIZE_MAX / page_size;
963 
964 	pages = parse_pages_arg(str, 1, max);
965 	if (pages < 0) {
966 		pr_err("Invalid argument for --mmap_pages/-m\n");
967 		return -1;
968 	}
969 
970 	*mmap_pages = pages;
971 	return 0;
972 }
973 
974 int evlist__parse_mmap_pages(const struct option *opt, const char *str, int unset __maybe_unused)
975 {
976 	return __evlist__parse_mmap_pages(opt->value, str);
977 }
978 
979 /**
980  * evlist__mmap_ex - Create mmaps to receive events.
981  * @evlist: list of events
982  * @pages: map length in pages
983  * @overwrite: overwrite older events?
984  * @auxtrace_pages - auxtrace map length in pages
985  * @auxtrace_overwrite - overwrite older auxtrace data?
986  *
987  * If @overwrite is %false the user needs to signal event consumption using
988  * perf_mmap__write_tail().  Using evlist__mmap_read() does this
989  * automatically.
990  *
991  * Similarly, if @auxtrace_overwrite is %false the user needs to signal data
992  * consumption using auxtrace_mmap__write_tail().
993  *
994  * Return: %0 on success, negative error code otherwise.
995  */
996 int evlist__mmap_ex(struct evlist *evlist, unsigned int pages,
997 			 unsigned int auxtrace_pages,
998 			 bool auxtrace_overwrite, int nr_cblocks, int affinity, int flush,
999 			 int comp_level)
1000 {
1001 	/*
1002 	 * Delay setting mp.prot: set it before calling perf_mmap__mmap.
1003 	 * Its value is decided by evsel's write_backward.
1004 	 * So &mp should not be passed through const pointer.
1005 	 */
1006 	struct mmap_params mp = {
1007 		.nr_cblocks	= nr_cblocks,
1008 		.affinity	= affinity,
1009 		.flush		= flush,
1010 		.comp_level	= comp_level
1011 	};
1012 	struct perf_evlist_mmap_ops ops = {
1013 		.idx  = perf_evlist__mmap_cb_idx,
1014 		.get  = perf_evlist__mmap_cb_get,
1015 		.mmap = perf_evlist__mmap_cb_mmap,
1016 	};
1017 
1018 	evlist->core.mmap_len = evlist__mmap_size(pages);
1019 	pr_debug("mmap size %zuB\n", evlist->core.mmap_len);
1020 
1021 	auxtrace_mmap_params__init(&mp.auxtrace_mp, evlist->core.mmap_len,
1022 				   auxtrace_pages, auxtrace_overwrite);
1023 
1024 	return perf_evlist__mmap_ops(&evlist->core, &ops, &mp.core);
1025 }
1026 
1027 int evlist__mmap(struct evlist *evlist, unsigned int pages)
1028 {
1029 	return evlist__mmap_ex(evlist, pages, 0, false, 0, PERF_AFFINITY_SYS, 1, 0);
1030 }
1031 
1032 int 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 && !target->hybrid;
1071 
1072 	perf_evlist__set_maps(&evlist->core, cpus, threads);
1073 
1074 	/* as evlist now has references, put count here */
1075 	perf_cpu_map__put(cpus);
1076 	perf_thread_map__put(threads);
1077 
1078 	return 0;
1079 
1080 out_delete_threads:
1081 	perf_thread_map__put(threads);
1082 	return -1;
1083 }
1084 
1085 int evlist__apply_filters(struct evlist *evlist, struct evsel **err_evsel)
1086 {
1087 	struct evsel *evsel;
1088 	int err = 0;
1089 
1090 	evlist__for_each_entry(evlist, evsel) {
1091 		if (evsel->filter == NULL)
1092 			continue;
1093 
1094 		/*
1095 		 * filters only work for tracepoint event, which doesn't have cpu limit.
1096 		 * So evlist and evsel should always be same.
1097 		 */
1098 		err = perf_evsel__apply_filter(&evsel->core, evsel->filter);
1099 		if (err) {
1100 			*err_evsel = evsel;
1101 			break;
1102 		}
1103 	}
1104 
1105 	return err;
1106 }
1107 
1108 int evlist__set_tp_filter(struct evlist *evlist, const char *filter)
1109 {
1110 	struct evsel *evsel;
1111 	int err = 0;
1112 
1113 	if (filter == NULL)
1114 		return -1;
1115 
1116 	evlist__for_each_entry(evlist, evsel) {
1117 		if (evsel->core.attr.type != PERF_TYPE_TRACEPOINT)
1118 			continue;
1119 
1120 		err = evsel__set_filter(evsel, filter);
1121 		if (err)
1122 			break;
1123 	}
1124 
1125 	return err;
1126 }
1127 
1128 int evlist__append_tp_filter(struct evlist *evlist, const char *filter)
1129 {
1130 	struct evsel *evsel;
1131 	int err = 0;
1132 
1133 	if (filter == NULL)
1134 		return -1;
1135 
1136 	evlist__for_each_entry(evlist, evsel) {
1137 		if (evsel->core.attr.type != PERF_TYPE_TRACEPOINT)
1138 			continue;
1139 
1140 		err = evsel__append_tp_filter(evsel, filter);
1141 		if (err)
1142 			break;
1143 	}
1144 
1145 	return err;
1146 }
1147 
1148 char *asprintf__tp_filter_pids(size_t npids, pid_t *pids)
1149 {
1150 	char *filter;
1151 	size_t i;
1152 
1153 	for (i = 0; i < npids; ++i) {
1154 		if (i == 0) {
1155 			if (asprintf(&filter, "common_pid != %d", pids[i]) < 0)
1156 				return NULL;
1157 		} else {
1158 			char *tmp;
1159 
1160 			if (asprintf(&tmp, "%s && common_pid != %d", filter, pids[i]) < 0)
1161 				goto out_free;
1162 
1163 			free(filter);
1164 			filter = tmp;
1165 		}
1166 	}
1167 
1168 	return filter;
1169 out_free:
1170 	free(filter);
1171 	return NULL;
1172 }
1173 
1174 int evlist__set_tp_filter_pids(struct evlist *evlist, size_t npids, pid_t *pids)
1175 {
1176 	char *filter = asprintf__tp_filter_pids(npids, pids);
1177 	int ret = evlist__set_tp_filter(evlist, filter);
1178 
1179 	free(filter);
1180 	return ret;
1181 }
1182 
1183 int evlist__set_tp_filter_pid(struct evlist *evlist, pid_t pid)
1184 {
1185 	return evlist__set_tp_filter_pids(evlist, 1, &pid);
1186 }
1187 
1188 int evlist__append_tp_filter_pids(struct evlist *evlist, size_t npids, pid_t *pids)
1189 {
1190 	char *filter = asprintf__tp_filter_pids(npids, pids);
1191 	int ret = evlist__append_tp_filter(evlist, filter);
1192 
1193 	free(filter);
1194 	return ret;
1195 }
1196 
1197 int evlist__append_tp_filter_pid(struct evlist *evlist, pid_t pid)
1198 {
1199 	return evlist__append_tp_filter_pids(evlist, 1, &pid);
1200 }
1201 
1202 bool evlist__valid_sample_type(struct evlist *evlist)
1203 {
1204 	struct evsel *pos;
1205 
1206 	if (evlist->core.nr_entries == 1)
1207 		return true;
1208 
1209 	if (evlist->id_pos < 0 || evlist->is_pos < 0)
1210 		return false;
1211 
1212 	evlist__for_each_entry(evlist, pos) {
1213 		if (pos->id_pos != evlist->id_pos ||
1214 		    pos->is_pos != evlist->is_pos)
1215 			return false;
1216 	}
1217 
1218 	return true;
1219 }
1220 
1221 u64 __evlist__combined_sample_type(struct evlist *evlist)
1222 {
1223 	struct evsel *evsel;
1224 
1225 	if (evlist->combined_sample_type)
1226 		return evlist->combined_sample_type;
1227 
1228 	evlist__for_each_entry(evlist, evsel)
1229 		evlist->combined_sample_type |= evsel->core.attr.sample_type;
1230 
1231 	return evlist->combined_sample_type;
1232 }
1233 
1234 u64 evlist__combined_sample_type(struct evlist *evlist)
1235 {
1236 	evlist->combined_sample_type = 0;
1237 	return __evlist__combined_sample_type(evlist);
1238 }
1239 
1240 u64 evlist__combined_branch_type(struct evlist *evlist)
1241 {
1242 	struct evsel *evsel;
1243 	u64 branch_type = 0;
1244 
1245 	evlist__for_each_entry(evlist, evsel)
1246 		branch_type |= evsel->core.attr.branch_sample_type;
1247 	return branch_type;
1248 }
1249 
1250 bool evlist__valid_read_format(struct evlist *evlist)
1251 {
1252 	struct evsel *first = evlist__first(evlist), *pos = first;
1253 	u64 read_format = first->core.attr.read_format;
1254 	u64 sample_type = first->core.attr.sample_type;
1255 
1256 	evlist__for_each_entry(evlist, pos) {
1257 		if (read_format != pos->core.attr.read_format) {
1258 			pr_debug("Read format differs %#" PRIx64 " vs %#" PRIx64 "\n",
1259 				 read_format, (u64)pos->core.attr.read_format);
1260 		}
1261 	}
1262 
1263 	/* PERF_SAMPLE_READ implies PERF_FORMAT_ID. */
1264 	if ((sample_type & PERF_SAMPLE_READ) &&
1265 	    !(read_format & PERF_FORMAT_ID)) {
1266 		return false;
1267 	}
1268 
1269 	return true;
1270 }
1271 
1272 u16 evlist__id_hdr_size(struct evlist *evlist)
1273 {
1274 	struct evsel *first = evlist__first(evlist);
1275 
1276 	return first->core.attr.sample_id_all ? evsel__id_hdr_size(first) : 0;
1277 }
1278 
1279 bool evlist__valid_sample_id_all(struct evlist *evlist)
1280 {
1281 	struct evsel *first = evlist__first(evlist), *pos = first;
1282 
1283 	evlist__for_each_entry_continue(evlist, pos) {
1284 		if (first->core.attr.sample_id_all != pos->core.attr.sample_id_all)
1285 			return false;
1286 	}
1287 
1288 	return true;
1289 }
1290 
1291 bool evlist__sample_id_all(struct evlist *evlist)
1292 {
1293 	struct evsel *first = evlist__first(evlist);
1294 	return first->core.attr.sample_id_all;
1295 }
1296 
1297 void evlist__set_selected(struct evlist *evlist, struct evsel *evsel)
1298 {
1299 	evlist->selected = evsel;
1300 }
1301 
1302 void evlist__close(struct evlist *evlist)
1303 {
1304 	struct evsel *evsel;
1305 	struct evlist_cpu_iterator evlist_cpu_itr;
1306 	struct affinity affinity;
1307 
1308 	/*
1309 	 * With perf record core.user_requested_cpus is usually NULL.
1310 	 * Use the old method to handle this for now.
1311 	 */
1312 	if (!evlist->core.user_requested_cpus ||
1313 	    cpu_map__is_dummy(evlist->core.user_requested_cpus)) {
1314 		evlist__for_each_entry_reverse(evlist, evsel)
1315 			evsel__close(evsel);
1316 		return;
1317 	}
1318 
1319 	if (affinity__setup(&affinity) < 0)
1320 		return;
1321 
1322 	evlist__for_each_cpu(evlist_cpu_itr, evlist, &affinity) {
1323 		perf_evsel__close_cpu(&evlist_cpu_itr.evsel->core,
1324 				      evlist_cpu_itr.cpu_map_idx);
1325 	}
1326 
1327 	affinity__cleanup(&affinity);
1328 	evlist__for_each_entry_reverse(evlist, evsel) {
1329 		perf_evsel__free_fd(&evsel->core);
1330 		perf_evsel__free_id(&evsel->core);
1331 	}
1332 	perf_evlist__reset_id_hash(&evlist->core);
1333 }
1334 
1335 static int evlist__create_syswide_maps(struct evlist *evlist)
1336 {
1337 	struct perf_cpu_map *cpus;
1338 	struct perf_thread_map *threads;
1339 
1340 	/*
1341 	 * Try reading /sys/devices/system/cpu/online to get
1342 	 * an all cpus map.
1343 	 *
1344 	 * FIXME: -ENOMEM is the best we can do here, the cpu_map
1345 	 * code needs an overhaul to properly forward the
1346 	 * error, and we may not want to do that fallback to a
1347 	 * default cpu identity map :-\
1348 	 */
1349 	cpus = perf_cpu_map__new(NULL);
1350 	if (!cpus)
1351 		goto out;
1352 
1353 	threads = perf_thread_map__new_dummy();
1354 	if (!threads)
1355 		goto out_put;
1356 
1357 	perf_evlist__set_maps(&evlist->core, cpus, threads);
1358 
1359 	perf_thread_map__put(threads);
1360 out_put:
1361 	perf_cpu_map__put(cpus);
1362 out:
1363 	return -ENOMEM;
1364 }
1365 
1366 int evlist__open(struct evlist *evlist)
1367 {
1368 	struct evsel *evsel;
1369 	int err;
1370 
1371 	/*
1372 	 * Default: one fd per CPU, all threads, aka systemwide
1373 	 * as sys_perf_event_open(cpu = -1, thread = -1) is EINVAL
1374 	 */
1375 	if (evlist->core.threads == NULL && evlist->core.user_requested_cpus == NULL) {
1376 		err = evlist__create_syswide_maps(evlist);
1377 		if (err < 0)
1378 			goto out_err;
1379 	}
1380 
1381 	evlist__update_id_pos(evlist);
1382 
1383 	evlist__for_each_entry(evlist, evsel) {
1384 		err = evsel__open(evsel, evsel->core.cpus, evsel->core.threads);
1385 		if (err < 0)
1386 			goto out_err;
1387 	}
1388 
1389 	return 0;
1390 out_err:
1391 	evlist__close(evlist);
1392 	errno = -err;
1393 	return err;
1394 }
1395 
1396 int evlist__prepare_workload(struct evlist *evlist, struct target *target, const char *argv[],
1397 			     bool pipe_output, void (*exec_error)(int signo, siginfo_t *info, void *ucontext))
1398 {
1399 	int child_ready_pipe[2], go_pipe[2];
1400 	char bf;
1401 
1402 	if (pipe(child_ready_pipe) < 0) {
1403 		perror("failed to create 'ready' pipe");
1404 		return -1;
1405 	}
1406 
1407 	if (pipe(go_pipe) < 0) {
1408 		perror("failed to create 'go' pipe");
1409 		goto out_close_ready_pipe;
1410 	}
1411 
1412 	evlist->workload.pid = fork();
1413 	if (evlist->workload.pid < 0) {
1414 		perror("failed to fork");
1415 		goto out_close_pipes;
1416 	}
1417 
1418 	if (!evlist->workload.pid) {
1419 		int ret;
1420 
1421 		if (pipe_output)
1422 			dup2(2, 1);
1423 
1424 		signal(SIGTERM, SIG_DFL);
1425 
1426 		close(child_ready_pipe[0]);
1427 		close(go_pipe[1]);
1428 		fcntl(go_pipe[0], F_SETFD, FD_CLOEXEC);
1429 
1430 		/*
1431 		 * Change the name of this process not to confuse --exclude-perf users
1432 		 * that sees 'perf' in the window up to the execvp() and thinks that
1433 		 * perf samples are not being excluded.
1434 		 */
1435 		prctl(PR_SET_NAME, "perf-exec");
1436 
1437 		/*
1438 		 * Tell the parent we're ready to go
1439 		 */
1440 		close(child_ready_pipe[1]);
1441 
1442 		/*
1443 		 * Wait until the parent tells us to go.
1444 		 */
1445 		ret = read(go_pipe[0], &bf, 1);
1446 		/*
1447 		 * The parent will ask for the execvp() to be performed by
1448 		 * writing exactly one byte, in workload.cork_fd, usually via
1449 		 * evlist__start_workload().
1450 		 *
1451 		 * For cancelling the workload without actually running it,
1452 		 * the parent will just close workload.cork_fd, without writing
1453 		 * anything, i.e. read will return zero and we just exit()
1454 		 * here.
1455 		 */
1456 		if (ret != 1) {
1457 			if (ret == -1)
1458 				perror("unable to read pipe");
1459 			exit(ret);
1460 		}
1461 
1462 		execvp(argv[0], (char **)argv);
1463 
1464 		if (exec_error) {
1465 			union sigval val;
1466 
1467 			val.sival_int = errno;
1468 			if (sigqueue(getppid(), SIGUSR1, val))
1469 				perror(argv[0]);
1470 		} else
1471 			perror(argv[0]);
1472 		exit(-1);
1473 	}
1474 
1475 	if (exec_error) {
1476 		struct sigaction act = {
1477 			.sa_flags     = SA_SIGINFO,
1478 			.sa_sigaction = exec_error,
1479 		};
1480 		sigaction(SIGUSR1, &act, NULL);
1481 	}
1482 
1483 	if (target__none(target)) {
1484 		if (evlist->core.threads == NULL) {
1485 			fprintf(stderr, "FATAL: evlist->threads need to be set at this point (%s:%d).\n",
1486 				__func__, __LINE__);
1487 			goto out_close_pipes;
1488 		}
1489 		perf_thread_map__set_pid(evlist->core.threads, 0, evlist->workload.pid);
1490 	}
1491 
1492 	close(child_ready_pipe[1]);
1493 	close(go_pipe[0]);
1494 	/*
1495 	 * wait for child to settle
1496 	 */
1497 	if (read(child_ready_pipe[0], &bf, 1) == -1) {
1498 		perror("unable to read pipe");
1499 		goto out_close_pipes;
1500 	}
1501 
1502 	fcntl(go_pipe[1], F_SETFD, FD_CLOEXEC);
1503 	evlist->workload.cork_fd = go_pipe[1];
1504 	close(child_ready_pipe[0]);
1505 	return 0;
1506 
1507 out_close_pipes:
1508 	close(go_pipe[0]);
1509 	close(go_pipe[1]);
1510 out_close_ready_pipe:
1511 	close(child_ready_pipe[0]);
1512 	close(child_ready_pipe[1]);
1513 	return -1;
1514 }
1515 
1516 int evlist__start_workload(struct evlist *evlist)
1517 {
1518 	if (evlist->workload.cork_fd > 0) {
1519 		char bf = 0;
1520 		int ret;
1521 		/*
1522 		 * Remove the cork, let it rip!
1523 		 */
1524 		ret = write(evlist->workload.cork_fd, &bf, 1);
1525 		if (ret < 0)
1526 			perror("unable to write to pipe");
1527 
1528 		close(evlist->workload.cork_fd);
1529 		return ret;
1530 	}
1531 
1532 	return 0;
1533 }
1534 
1535 int evlist__parse_sample(struct evlist *evlist, union perf_event *event, struct perf_sample *sample)
1536 {
1537 	struct evsel *evsel = evlist__event2evsel(evlist, event);
1538 	int ret;
1539 
1540 	if (!evsel)
1541 		return -EFAULT;
1542 	ret = evsel__parse_sample(evsel, event, sample);
1543 	if (ret)
1544 		return ret;
1545 	if (perf_guest && sample->id) {
1546 		struct perf_sample_id *sid = evlist__id2sid(evlist, sample->id);
1547 
1548 		if (sid) {
1549 			sample->machine_pid = sid->machine_pid;
1550 			sample->vcpu = sid->vcpu.cpu;
1551 		}
1552 	}
1553 	return 0;
1554 }
1555 
1556 int evlist__parse_sample_timestamp(struct evlist *evlist, union perf_event *event, u64 *timestamp)
1557 {
1558 	struct evsel *evsel = evlist__event2evsel(evlist, event);
1559 
1560 	if (!evsel)
1561 		return -EFAULT;
1562 	return evsel__parse_sample_timestamp(evsel, event, timestamp);
1563 }
1564 
1565 int evlist__strerror_open(struct evlist *evlist, int err, char *buf, size_t size)
1566 {
1567 	int printed, value;
1568 	char sbuf[STRERR_BUFSIZE], *emsg = str_error_r(err, sbuf, sizeof(sbuf));
1569 
1570 	switch (err) {
1571 	case EACCES:
1572 	case EPERM:
1573 		printed = scnprintf(buf, size,
1574 				    "Error:\t%s.\n"
1575 				    "Hint:\tCheck /proc/sys/kernel/perf_event_paranoid setting.", emsg);
1576 
1577 		value = perf_event_paranoid();
1578 
1579 		printed += scnprintf(buf + printed, size - printed, "\nHint:\t");
1580 
1581 		if (value >= 2) {
1582 			printed += scnprintf(buf + printed, size - printed,
1583 					     "For your workloads it needs to be <= 1\nHint:\t");
1584 		}
1585 		printed += scnprintf(buf + printed, size - printed,
1586 				     "For system wide tracing it needs to be set to -1.\n");
1587 
1588 		printed += scnprintf(buf + printed, size - printed,
1589 				    "Hint:\tTry: 'sudo sh -c \"echo -1 > /proc/sys/kernel/perf_event_paranoid\"'\n"
1590 				    "Hint:\tThe current value is %d.", value);
1591 		break;
1592 	case EINVAL: {
1593 		struct evsel *first = evlist__first(evlist);
1594 		int max_freq;
1595 
1596 		if (sysctl__read_int("kernel/perf_event_max_sample_rate", &max_freq) < 0)
1597 			goto out_default;
1598 
1599 		if (first->core.attr.sample_freq < (u64)max_freq)
1600 			goto out_default;
1601 
1602 		printed = scnprintf(buf, size,
1603 				    "Error:\t%s.\n"
1604 				    "Hint:\tCheck /proc/sys/kernel/perf_event_max_sample_rate.\n"
1605 				    "Hint:\tThe current value is %d and %" PRIu64 " is being requested.",
1606 				    emsg, max_freq, first->core.attr.sample_freq);
1607 		break;
1608 	}
1609 	default:
1610 out_default:
1611 		scnprintf(buf, size, "%s", emsg);
1612 		break;
1613 	}
1614 
1615 	return 0;
1616 }
1617 
1618 int evlist__strerror_mmap(struct evlist *evlist, int err, char *buf, size_t size)
1619 {
1620 	char sbuf[STRERR_BUFSIZE], *emsg = str_error_r(err, sbuf, sizeof(sbuf));
1621 	int pages_attempted = evlist->core.mmap_len / 1024, pages_max_per_user, printed = 0;
1622 
1623 	switch (err) {
1624 	case EPERM:
1625 		sysctl__read_int("kernel/perf_event_mlock_kb", &pages_max_per_user);
1626 		printed += scnprintf(buf + printed, size - printed,
1627 				     "Error:\t%s.\n"
1628 				     "Hint:\tCheck /proc/sys/kernel/perf_event_mlock_kb (%d kB) setting.\n"
1629 				     "Hint:\tTried using %zd kB.\n",
1630 				     emsg, pages_max_per_user, pages_attempted);
1631 
1632 		if (pages_attempted >= pages_max_per_user) {
1633 			printed += scnprintf(buf + printed, size - printed,
1634 					     "Hint:\tTry 'sudo sh -c \"echo %d > /proc/sys/kernel/perf_event_mlock_kb\"', or\n",
1635 					     pages_max_per_user + pages_attempted);
1636 		}
1637 
1638 		printed += scnprintf(buf + printed, size - printed,
1639 				     "Hint:\tTry using a smaller -m/--mmap-pages value.");
1640 		break;
1641 	default:
1642 		scnprintf(buf, size, "%s", emsg);
1643 		break;
1644 	}
1645 
1646 	return 0;
1647 }
1648 
1649 void evlist__to_front(struct evlist *evlist, struct evsel *move_evsel)
1650 {
1651 	struct evsel *evsel, *n;
1652 	LIST_HEAD(move);
1653 
1654 	if (move_evsel == evlist__first(evlist))
1655 		return;
1656 
1657 	evlist__for_each_entry_safe(evlist, n, evsel) {
1658 		if (evsel__leader(evsel) == evsel__leader(move_evsel))
1659 			list_move_tail(&evsel->core.node, &move);
1660 	}
1661 
1662 	list_splice(&move, &evlist->core.entries);
1663 }
1664 
1665 struct evsel *evlist__get_tracking_event(struct evlist *evlist)
1666 {
1667 	struct evsel *evsel;
1668 
1669 	evlist__for_each_entry(evlist, evsel) {
1670 		if (evsel->tracking)
1671 			return evsel;
1672 	}
1673 
1674 	return evlist__first(evlist);
1675 }
1676 
1677 void evlist__set_tracking_event(struct evlist *evlist, struct evsel *tracking_evsel)
1678 {
1679 	struct evsel *evsel;
1680 
1681 	if (tracking_evsel->tracking)
1682 		return;
1683 
1684 	evlist__for_each_entry(evlist, evsel) {
1685 		if (evsel != tracking_evsel)
1686 			evsel->tracking = false;
1687 	}
1688 
1689 	tracking_evsel->tracking = true;
1690 }
1691 
1692 struct evsel *evlist__find_evsel_by_str(struct evlist *evlist, const char *str)
1693 {
1694 	struct evsel *evsel;
1695 
1696 	evlist__for_each_entry(evlist, evsel) {
1697 		if (!evsel->name)
1698 			continue;
1699 		if (strcmp(str, evsel->name) == 0)
1700 			return evsel;
1701 	}
1702 
1703 	return NULL;
1704 }
1705 
1706 void evlist__toggle_bkw_mmap(struct evlist *evlist, enum bkw_mmap_state state)
1707 {
1708 	enum bkw_mmap_state old_state = evlist->bkw_mmap_state;
1709 	enum action {
1710 		NONE,
1711 		PAUSE,
1712 		RESUME,
1713 	} action = NONE;
1714 
1715 	if (!evlist->overwrite_mmap)
1716 		return;
1717 
1718 	switch (old_state) {
1719 	case BKW_MMAP_NOTREADY: {
1720 		if (state != BKW_MMAP_RUNNING)
1721 			goto state_err;
1722 		break;
1723 	}
1724 	case BKW_MMAP_RUNNING: {
1725 		if (state != BKW_MMAP_DATA_PENDING)
1726 			goto state_err;
1727 		action = PAUSE;
1728 		break;
1729 	}
1730 	case BKW_MMAP_DATA_PENDING: {
1731 		if (state != BKW_MMAP_EMPTY)
1732 			goto state_err;
1733 		break;
1734 	}
1735 	case BKW_MMAP_EMPTY: {
1736 		if (state != BKW_MMAP_RUNNING)
1737 			goto state_err;
1738 		action = RESUME;
1739 		break;
1740 	}
1741 	default:
1742 		WARN_ONCE(1, "Shouldn't get there\n");
1743 	}
1744 
1745 	evlist->bkw_mmap_state = state;
1746 
1747 	switch (action) {
1748 	case PAUSE:
1749 		evlist__pause(evlist);
1750 		break;
1751 	case RESUME:
1752 		evlist__resume(evlist);
1753 		break;
1754 	case NONE:
1755 	default:
1756 		break;
1757 	}
1758 
1759 state_err:
1760 	return;
1761 }
1762 
1763 bool evlist__exclude_kernel(struct evlist *evlist)
1764 {
1765 	struct evsel *evsel;
1766 
1767 	evlist__for_each_entry(evlist, evsel) {
1768 		if (!evsel->core.attr.exclude_kernel)
1769 			return false;
1770 	}
1771 
1772 	return true;
1773 }
1774 
1775 /*
1776  * Events in data file are not collect in groups, but we still want
1777  * the group display. Set the artificial group and set the leader's
1778  * forced_leader flag to notify the display code.
1779  */
1780 void evlist__force_leader(struct evlist *evlist)
1781 {
1782 	if (!evlist->core.nr_groups) {
1783 		struct evsel *leader = evlist__first(evlist);
1784 
1785 		evlist__set_leader(evlist);
1786 		leader->forced_leader = true;
1787 	}
1788 }
1789 
1790 struct evsel *evlist__reset_weak_group(struct evlist *evsel_list, struct evsel *evsel, bool close)
1791 {
1792 	struct evsel *c2, *leader;
1793 	bool is_open = true;
1794 
1795 	leader = evsel__leader(evsel);
1796 
1797 	pr_debug("Weak group for %s/%d failed\n",
1798 			leader->name, leader->core.nr_members);
1799 
1800 	/*
1801 	 * for_each_group_member doesn't work here because it doesn't
1802 	 * include the first entry.
1803 	 */
1804 	evlist__for_each_entry(evsel_list, c2) {
1805 		if (c2 == evsel)
1806 			is_open = false;
1807 		if (evsel__has_leader(c2, leader)) {
1808 			if (is_open && close)
1809 				perf_evsel__close(&c2->core);
1810 			/*
1811 			 * We want to close all members of the group and reopen
1812 			 * them. Some events, like Intel topdown, require being
1813 			 * in a group and so keep these in the group.
1814 			 */
1815 			evsel__remove_from_group(c2, leader);
1816 
1817 			/*
1818 			 * Set this for all former members of the group
1819 			 * to indicate they get reopened.
1820 			 */
1821 			c2->reset_group = true;
1822 		}
1823 	}
1824 	/* Reset the leader count if all entries were removed. */
1825 	if (leader->core.nr_members == 1)
1826 		leader->core.nr_members = 0;
1827 	return leader;
1828 }
1829 
1830 static int evlist__parse_control_fifo(const char *str, int *ctl_fd, int *ctl_fd_ack, bool *ctl_fd_close)
1831 {
1832 	char *s, *p;
1833 	int ret = 0, fd;
1834 
1835 	if (strncmp(str, "fifo:", 5))
1836 		return -EINVAL;
1837 
1838 	str += 5;
1839 	if (!*str || *str == ',')
1840 		return -EINVAL;
1841 
1842 	s = strdup(str);
1843 	if (!s)
1844 		return -ENOMEM;
1845 
1846 	p = strchr(s, ',');
1847 	if (p)
1848 		*p = '\0';
1849 
1850 	/*
1851 	 * O_RDWR avoids POLLHUPs which is necessary to allow the other
1852 	 * end of a FIFO to be repeatedly opened and closed.
1853 	 */
1854 	fd = open(s, O_RDWR | O_NONBLOCK | O_CLOEXEC);
1855 	if (fd < 0) {
1856 		pr_err("Failed to open '%s'\n", s);
1857 		ret = -errno;
1858 		goto out_free;
1859 	}
1860 	*ctl_fd = fd;
1861 	*ctl_fd_close = true;
1862 
1863 	if (p && *++p) {
1864 		/* O_RDWR | O_NONBLOCK means the other end need not be open */
1865 		fd = open(p, O_RDWR | O_NONBLOCK | O_CLOEXEC);
1866 		if (fd < 0) {
1867 			pr_err("Failed to open '%s'\n", p);
1868 			ret = -errno;
1869 			goto out_free;
1870 		}
1871 		*ctl_fd_ack = fd;
1872 	}
1873 
1874 out_free:
1875 	free(s);
1876 	return ret;
1877 }
1878 
1879 int evlist__parse_control(const char *str, int *ctl_fd, int *ctl_fd_ack, bool *ctl_fd_close)
1880 {
1881 	char *comma = NULL, *endptr = NULL;
1882 
1883 	*ctl_fd_close = false;
1884 
1885 	if (strncmp(str, "fd:", 3))
1886 		return evlist__parse_control_fifo(str, ctl_fd, ctl_fd_ack, ctl_fd_close);
1887 
1888 	*ctl_fd = strtoul(&str[3], &endptr, 0);
1889 	if (endptr == &str[3])
1890 		return -EINVAL;
1891 
1892 	comma = strchr(str, ',');
1893 	if (comma) {
1894 		if (endptr != comma)
1895 			return -EINVAL;
1896 
1897 		*ctl_fd_ack = strtoul(comma + 1, &endptr, 0);
1898 		if (endptr == comma + 1 || *endptr != '\0')
1899 			return -EINVAL;
1900 	}
1901 
1902 	return 0;
1903 }
1904 
1905 void evlist__close_control(int ctl_fd, int ctl_fd_ack, bool *ctl_fd_close)
1906 {
1907 	if (*ctl_fd_close) {
1908 		*ctl_fd_close = false;
1909 		close(ctl_fd);
1910 		if (ctl_fd_ack >= 0)
1911 			close(ctl_fd_ack);
1912 	}
1913 }
1914 
1915 int evlist__initialize_ctlfd(struct evlist *evlist, int fd, int ack)
1916 {
1917 	if (fd == -1) {
1918 		pr_debug("Control descriptor is not initialized\n");
1919 		return 0;
1920 	}
1921 
1922 	evlist->ctl_fd.pos = perf_evlist__add_pollfd(&evlist->core, fd, NULL, POLLIN,
1923 						     fdarray_flag__nonfilterable |
1924 						     fdarray_flag__non_perf_event);
1925 	if (evlist->ctl_fd.pos < 0) {
1926 		evlist->ctl_fd.pos = -1;
1927 		pr_err("Failed to add ctl fd entry: %m\n");
1928 		return -1;
1929 	}
1930 
1931 	evlist->ctl_fd.fd = fd;
1932 	evlist->ctl_fd.ack = ack;
1933 
1934 	return 0;
1935 }
1936 
1937 bool evlist__ctlfd_initialized(struct evlist *evlist)
1938 {
1939 	return evlist->ctl_fd.pos >= 0;
1940 }
1941 
1942 int evlist__finalize_ctlfd(struct evlist *evlist)
1943 {
1944 	struct pollfd *entries = evlist->core.pollfd.entries;
1945 
1946 	if (!evlist__ctlfd_initialized(evlist))
1947 		return 0;
1948 
1949 	entries[evlist->ctl_fd.pos].fd = -1;
1950 	entries[evlist->ctl_fd.pos].events = 0;
1951 	entries[evlist->ctl_fd.pos].revents = 0;
1952 
1953 	evlist->ctl_fd.pos = -1;
1954 	evlist->ctl_fd.ack = -1;
1955 	evlist->ctl_fd.fd = -1;
1956 
1957 	return 0;
1958 }
1959 
1960 static int evlist__ctlfd_recv(struct evlist *evlist, enum evlist_ctl_cmd *cmd,
1961 			      char *cmd_data, size_t data_size)
1962 {
1963 	int err;
1964 	char c;
1965 	size_t bytes_read = 0;
1966 
1967 	*cmd = EVLIST_CTL_CMD_UNSUPPORTED;
1968 	memset(cmd_data, 0, data_size);
1969 	data_size--;
1970 
1971 	do {
1972 		err = read(evlist->ctl_fd.fd, &c, 1);
1973 		if (err > 0) {
1974 			if (c == '\n' || c == '\0')
1975 				break;
1976 			cmd_data[bytes_read++] = c;
1977 			if (bytes_read == data_size)
1978 				break;
1979 			continue;
1980 		} else if (err == -1) {
1981 			if (errno == EINTR)
1982 				continue;
1983 			if (errno == EAGAIN || errno == EWOULDBLOCK)
1984 				err = 0;
1985 			else
1986 				pr_err("Failed to read from ctlfd %d: %m\n", evlist->ctl_fd.fd);
1987 		}
1988 		break;
1989 	} while (1);
1990 
1991 	pr_debug("Message from ctl_fd: \"%s%s\"\n", cmd_data,
1992 		 bytes_read == data_size ? "" : c == '\n' ? "\\n" : "\\0");
1993 
1994 	if (bytes_read > 0) {
1995 		if (!strncmp(cmd_data, EVLIST_CTL_CMD_ENABLE_TAG,
1996 			     (sizeof(EVLIST_CTL_CMD_ENABLE_TAG)-1))) {
1997 			*cmd = EVLIST_CTL_CMD_ENABLE;
1998 		} else if (!strncmp(cmd_data, EVLIST_CTL_CMD_DISABLE_TAG,
1999 				    (sizeof(EVLIST_CTL_CMD_DISABLE_TAG)-1))) {
2000 			*cmd = EVLIST_CTL_CMD_DISABLE;
2001 		} else if (!strncmp(cmd_data, EVLIST_CTL_CMD_SNAPSHOT_TAG,
2002 				    (sizeof(EVLIST_CTL_CMD_SNAPSHOT_TAG)-1))) {
2003 			*cmd = EVLIST_CTL_CMD_SNAPSHOT;
2004 			pr_debug("is snapshot\n");
2005 		} else if (!strncmp(cmd_data, EVLIST_CTL_CMD_EVLIST_TAG,
2006 				    (sizeof(EVLIST_CTL_CMD_EVLIST_TAG)-1))) {
2007 			*cmd = EVLIST_CTL_CMD_EVLIST;
2008 		} else if (!strncmp(cmd_data, EVLIST_CTL_CMD_STOP_TAG,
2009 				    (sizeof(EVLIST_CTL_CMD_STOP_TAG)-1))) {
2010 			*cmd = EVLIST_CTL_CMD_STOP;
2011 		} else if (!strncmp(cmd_data, EVLIST_CTL_CMD_PING_TAG,
2012 				    (sizeof(EVLIST_CTL_CMD_PING_TAG)-1))) {
2013 			*cmd = EVLIST_CTL_CMD_PING;
2014 		}
2015 	}
2016 
2017 	return bytes_read ? (int)bytes_read : err;
2018 }
2019 
2020 int evlist__ctlfd_ack(struct evlist *evlist)
2021 {
2022 	int err;
2023 
2024 	if (evlist->ctl_fd.ack == -1)
2025 		return 0;
2026 
2027 	err = write(evlist->ctl_fd.ack, EVLIST_CTL_CMD_ACK_TAG,
2028 		    sizeof(EVLIST_CTL_CMD_ACK_TAG));
2029 	if (err == -1)
2030 		pr_err("failed to write to ctl_ack_fd %d: %m\n", evlist->ctl_fd.ack);
2031 
2032 	return err;
2033 }
2034 
2035 static int get_cmd_arg(char *cmd_data, size_t cmd_size, char **arg)
2036 {
2037 	char *data = cmd_data + cmd_size;
2038 
2039 	/* no argument */
2040 	if (!*data)
2041 		return 0;
2042 
2043 	/* there's argument */
2044 	if (*data == ' ') {
2045 		*arg = data + 1;
2046 		return 1;
2047 	}
2048 
2049 	/* malformed */
2050 	return -1;
2051 }
2052 
2053 static int evlist__ctlfd_enable(struct evlist *evlist, char *cmd_data, bool enable)
2054 {
2055 	struct evsel *evsel;
2056 	char *name;
2057 	int err;
2058 
2059 	err = get_cmd_arg(cmd_data,
2060 			  enable ? sizeof(EVLIST_CTL_CMD_ENABLE_TAG) - 1 :
2061 				   sizeof(EVLIST_CTL_CMD_DISABLE_TAG) - 1,
2062 			  &name);
2063 	if (err < 0) {
2064 		pr_info("failed: wrong command\n");
2065 		return -1;
2066 	}
2067 
2068 	if (err) {
2069 		evsel = evlist__find_evsel_by_str(evlist, name);
2070 		if (evsel) {
2071 			if (enable)
2072 				evlist__enable_evsel(evlist, name);
2073 			else
2074 				evlist__disable_evsel(evlist, name);
2075 			pr_info("Event %s %s\n", evsel->name,
2076 				enable ? "enabled" : "disabled");
2077 		} else {
2078 			pr_info("failed: can't find '%s' event\n", name);
2079 		}
2080 	} else {
2081 		if (enable) {
2082 			evlist__enable(evlist);
2083 			pr_info(EVLIST_ENABLED_MSG);
2084 		} else {
2085 			evlist__disable(evlist);
2086 			pr_info(EVLIST_DISABLED_MSG);
2087 		}
2088 	}
2089 
2090 	return 0;
2091 }
2092 
2093 static int evlist__ctlfd_list(struct evlist *evlist, char *cmd_data)
2094 {
2095 	struct perf_attr_details details = { .verbose = false, };
2096 	struct evsel *evsel;
2097 	char *arg;
2098 	int err;
2099 
2100 	err = get_cmd_arg(cmd_data,
2101 			  sizeof(EVLIST_CTL_CMD_EVLIST_TAG) - 1,
2102 			  &arg);
2103 	if (err < 0) {
2104 		pr_info("failed: wrong command\n");
2105 		return -1;
2106 	}
2107 
2108 	if (err) {
2109 		if (!strcmp(arg, "-v")) {
2110 			details.verbose = true;
2111 		} else if (!strcmp(arg, "-g")) {
2112 			details.event_group = true;
2113 		} else if (!strcmp(arg, "-F")) {
2114 			details.freq = true;
2115 		} else {
2116 			pr_info("failed: wrong command\n");
2117 			return -1;
2118 		}
2119 	}
2120 
2121 	evlist__for_each_entry(evlist, evsel)
2122 		evsel__fprintf(evsel, &details, stderr);
2123 
2124 	return 0;
2125 }
2126 
2127 int evlist__ctlfd_process(struct evlist *evlist, enum evlist_ctl_cmd *cmd)
2128 {
2129 	int err = 0;
2130 	char cmd_data[EVLIST_CTL_CMD_MAX_LEN];
2131 	int ctlfd_pos = evlist->ctl_fd.pos;
2132 	struct pollfd *entries = evlist->core.pollfd.entries;
2133 
2134 	if (!evlist__ctlfd_initialized(evlist) || !entries[ctlfd_pos].revents)
2135 		return 0;
2136 
2137 	if (entries[ctlfd_pos].revents & POLLIN) {
2138 		err = evlist__ctlfd_recv(evlist, cmd, cmd_data,
2139 					 EVLIST_CTL_CMD_MAX_LEN);
2140 		if (err > 0) {
2141 			switch (*cmd) {
2142 			case EVLIST_CTL_CMD_ENABLE:
2143 			case EVLIST_CTL_CMD_DISABLE:
2144 				err = evlist__ctlfd_enable(evlist, cmd_data,
2145 							   *cmd == EVLIST_CTL_CMD_ENABLE);
2146 				break;
2147 			case EVLIST_CTL_CMD_EVLIST:
2148 				err = evlist__ctlfd_list(evlist, cmd_data);
2149 				break;
2150 			case EVLIST_CTL_CMD_SNAPSHOT:
2151 			case EVLIST_CTL_CMD_STOP:
2152 			case EVLIST_CTL_CMD_PING:
2153 				break;
2154 			case EVLIST_CTL_CMD_ACK:
2155 			case EVLIST_CTL_CMD_UNSUPPORTED:
2156 			default:
2157 				pr_debug("ctlfd: unsupported %d\n", *cmd);
2158 				break;
2159 			}
2160 			if (!(*cmd == EVLIST_CTL_CMD_ACK || *cmd == EVLIST_CTL_CMD_UNSUPPORTED ||
2161 			      *cmd == EVLIST_CTL_CMD_SNAPSHOT))
2162 				evlist__ctlfd_ack(evlist);
2163 		}
2164 	}
2165 
2166 	if (entries[ctlfd_pos].revents & (POLLHUP | POLLERR))
2167 		evlist__finalize_ctlfd(evlist);
2168 	else
2169 		entries[ctlfd_pos].revents = 0;
2170 
2171 	return err;
2172 }
2173 
2174 /**
2175  * struct event_enable_time - perf record -D/--delay single time range.
2176  * @start: start of time range to enable events in milliseconds
2177  * @end: end of time range to enable events in milliseconds
2178  *
2179  * N.B. this structure is also accessed as an array of int.
2180  */
2181 struct event_enable_time {
2182 	int	start;
2183 	int	end;
2184 };
2185 
2186 static int parse_event_enable_time(const char *str, struct event_enable_time *range, bool first)
2187 {
2188 	const char *fmt = first ? "%u - %u %n" : " , %u - %u %n";
2189 	int ret, start, end, n;
2190 
2191 	ret = sscanf(str, fmt, &start, &end, &n);
2192 	if (ret != 2 || end <= start)
2193 		return -EINVAL;
2194 	if (range) {
2195 		range->start = start;
2196 		range->end = end;
2197 	}
2198 	return n;
2199 }
2200 
2201 static ssize_t parse_event_enable_times(const char *str, struct event_enable_time *range)
2202 {
2203 	int incr = !!range;
2204 	bool first = true;
2205 	ssize_t ret, cnt;
2206 
2207 	for (cnt = 0; *str; cnt++) {
2208 		ret = parse_event_enable_time(str, range, first);
2209 		if (ret < 0)
2210 			return ret;
2211 		/* Check no overlap */
2212 		if (!first && range && range->start <= range[-1].end)
2213 			return -EINVAL;
2214 		str += ret;
2215 		range += incr;
2216 		first = false;
2217 	}
2218 	return cnt;
2219 }
2220 
2221 /**
2222  * struct event_enable_timer - control structure for perf record -D/--delay.
2223  * @evlist: event list
2224  * @times: time ranges that events are enabled (N.B. this is also accessed as an
2225  *         array of int)
2226  * @times_cnt: number of time ranges
2227  * @timerfd: timer file descriptor
2228  * @pollfd_pos: position in @evlist array of file descriptors to poll (fdarray)
2229  * @times_step: current position in (int *)@times)[],
2230  *              refer event_enable_timer__process()
2231  *
2232  * Note, this structure is only used when there are time ranges, not when there
2233  * is only an initial delay.
2234  */
2235 struct event_enable_timer {
2236 	struct evlist *evlist;
2237 	struct event_enable_time *times;
2238 	size_t	times_cnt;
2239 	int	timerfd;
2240 	int	pollfd_pos;
2241 	size_t	times_step;
2242 };
2243 
2244 static int str_to_delay(const char *str)
2245 {
2246 	char *endptr;
2247 	long d;
2248 
2249 	d = strtol(str, &endptr, 10);
2250 	if (*endptr || d > INT_MAX || d < -1)
2251 		return 0;
2252 	return d;
2253 }
2254 
2255 int evlist__parse_event_enable_time(struct evlist *evlist, struct record_opts *opts,
2256 				    const char *str, int unset)
2257 {
2258 	enum fdarray_flags flags = fdarray_flag__nonfilterable | fdarray_flag__non_perf_event;
2259 	struct event_enable_timer *eet;
2260 	ssize_t times_cnt;
2261 	ssize_t ret;
2262 	int err;
2263 
2264 	if (unset)
2265 		return 0;
2266 
2267 	opts->initial_delay = str_to_delay(str);
2268 	if (opts->initial_delay)
2269 		return 0;
2270 
2271 	ret = parse_event_enable_times(str, NULL);
2272 	if (ret < 0)
2273 		return ret;
2274 
2275 	times_cnt = ret;
2276 	if (times_cnt == 0)
2277 		return -EINVAL;
2278 
2279 	eet = zalloc(sizeof(*eet));
2280 	if (!eet)
2281 		return -ENOMEM;
2282 
2283 	eet->times = calloc(times_cnt, sizeof(*eet->times));
2284 	if (!eet->times) {
2285 		err = -ENOMEM;
2286 		goto free_eet;
2287 	}
2288 
2289 	if (parse_event_enable_times(str, eet->times) != times_cnt) {
2290 		err = -EINVAL;
2291 		goto free_eet_times;
2292 	}
2293 
2294 	eet->times_cnt = times_cnt;
2295 
2296 	eet->timerfd = timerfd_create(CLOCK_MONOTONIC, TFD_CLOEXEC);
2297 	if (eet->timerfd == -1) {
2298 		err = -errno;
2299 		pr_err("timerfd_create failed: %s\n", strerror(errno));
2300 		goto free_eet_times;
2301 	}
2302 
2303 	eet->pollfd_pos = perf_evlist__add_pollfd(&evlist->core, eet->timerfd, NULL, POLLIN, flags);
2304 	if (eet->pollfd_pos < 0) {
2305 		err = eet->pollfd_pos;
2306 		goto close_timerfd;
2307 	}
2308 
2309 	eet->evlist = evlist;
2310 	evlist->eet = eet;
2311 	opts->initial_delay = eet->times[0].start;
2312 
2313 	return 0;
2314 
2315 close_timerfd:
2316 	close(eet->timerfd);
2317 free_eet_times:
2318 	free(eet->times);
2319 free_eet:
2320 	free(eet);
2321 	return err;
2322 }
2323 
2324 static int event_enable_timer__set_timer(struct event_enable_timer *eet, int ms)
2325 {
2326 	struct itimerspec its = {
2327 		.it_value.tv_sec = ms / MSEC_PER_SEC,
2328 		.it_value.tv_nsec = (ms % MSEC_PER_SEC) * NSEC_PER_MSEC,
2329 	};
2330 	int err = 0;
2331 
2332 	if (timerfd_settime(eet->timerfd, 0, &its, NULL) < 0) {
2333 		err = -errno;
2334 		pr_err("timerfd_settime failed: %s\n", strerror(errno));
2335 	}
2336 	return err;
2337 }
2338 
2339 int event_enable_timer__start(struct event_enable_timer *eet)
2340 {
2341 	int ms;
2342 
2343 	if (!eet)
2344 		return 0;
2345 
2346 	ms = eet->times[0].end - eet->times[0].start;
2347 	eet->times_step = 1;
2348 
2349 	return event_enable_timer__set_timer(eet, ms);
2350 }
2351 
2352 int event_enable_timer__process(struct event_enable_timer *eet)
2353 {
2354 	struct pollfd *entries;
2355 	short revents;
2356 
2357 	if (!eet)
2358 		return 0;
2359 
2360 	entries = eet->evlist->core.pollfd.entries;
2361 	revents = entries[eet->pollfd_pos].revents;
2362 	entries[eet->pollfd_pos].revents = 0;
2363 
2364 	if (revents & POLLIN) {
2365 		size_t step = eet->times_step;
2366 		size_t pos = step / 2;
2367 
2368 		if (step & 1) {
2369 			evlist__disable_non_dummy(eet->evlist);
2370 			pr_info(EVLIST_DISABLED_MSG);
2371 			if (pos >= eet->times_cnt - 1) {
2372 				/* Disarm timer */
2373 				event_enable_timer__set_timer(eet, 0);
2374 				return 1; /* Stop */
2375 			}
2376 		} else {
2377 			evlist__enable_non_dummy(eet->evlist);
2378 			pr_info(EVLIST_ENABLED_MSG);
2379 		}
2380 
2381 		step += 1;
2382 		pos = step / 2;
2383 
2384 		if (pos < eet->times_cnt) {
2385 			int *times = (int *)eet->times; /* Accessing 'times' as array of int */
2386 			int ms = times[step] - times[step - 1];
2387 
2388 			eet->times_step = step;
2389 			return event_enable_timer__set_timer(eet, ms);
2390 		}
2391 	}
2392 
2393 	return 0;
2394 }
2395 
2396 void event_enable_timer__exit(struct event_enable_timer **ep)
2397 {
2398 	if (!ep || !*ep)
2399 		return;
2400 	free((*ep)->times);
2401 	zfree(ep);
2402 }
2403 
2404 struct evsel *evlist__find_evsel(struct evlist *evlist, int idx)
2405 {
2406 	struct evsel *evsel;
2407 
2408 	evlist__for_each_entry(evlist, evsel) {
2409 		if (evsel->core.idx == idx)
2410 			return evsel;
2411 	}
2412 	return NULL;
2413 }
2414 
2415 int evlist__scnprintf_evsels(struct evlist *evlist, size_t size, char *bf)
2416 {
2417 	struct evsel *evsel;
2418 	int printed = 0;
2419 
2420 	evlist__for_each_entry(evlist, evsel) {
2421 		if (evsel__is_dummy_event(evsel))
2422 			continue;
2423 		if (size > (strlen(evsel__name(evsel)) + (printed ? 2 : 1))) {
2424 			printed += scnprintf(bf + printed, size - printed, "%s%s", printed ? "," : "", evsel__name(evsel));
2425 		} else {
2426 			printed += scnprintf(bf + printed, size - printed, "%s...", printed ? "," : "");
2427 			break;
2428 		}
2429 	}
2430 
2431 	return printed;
2432 }
2433 
2434 void evlist__check_mem_load_aux(struct evlist *evlist)
2435 {
2436 	struct evsel *leader, *evsel, *pos;
2437 
2438 	/*
2439 	 * For some platforms, the 'mem-loads' event is required to use
2440 	 * together with 'mem-loads-aux' within a group and 'mem-loads-aux'
2441 	 * must be the group leader. Now we disable this group before reporting
2442 	 * because 'mem-loads-aux' is just an auxiliary event. It doesn't carry
2443 	 * any valid memory load information.
2444 	 */
2445 	evlist__for_each_entry(evlist, evsel) {
2446 		leader = evsel__leader(evsel);
2447 		if (leader == evsel)
2448 			continue;
2449 
2450 		if (leader->name && strstr(leader->name, "mem-loads-aux")) {
2451 			for_each_group_evsel(pos, leader) {
2452 				evsel__set_leader(pos, pos);
2453 				pos->core.nr_members = 0;
2454 			}
2455 		}
2456 	}
2457 }
2458