xref: /linux/tools/perf/util/evlist.c (revision af9e8d12b139c92e748eb2956bbef03315ea7516)
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/event.h"
28 #include "util/string2.h"
29 #include "util/perf_api_probe.h"
30 #include "util/evsel_fprintf.h"
31 #include "util/pmu.h"
32 #include "util/sample.h"
33 #include "util/bpf-filter.h"
34 #include "util/stat.h"
35 #include "util/util.h"
36 #include "util/env.h"
37 #include "util/intel-tpebs.h"
38 #include "util/metricgroup.h"
39 #include "util/strbuf.h"
40 #include <signal.h>
41 #include <unistd.h>
42 #include <sched.h>
43 #include <stdlib.h>
44 
45 #include "parse-events.h"
46 #include <subcmd/parse-options.h>
47 
48 #include <fcntl.h>
49 #include <sys/ioctl.h>
50 #include <sys/mman.h>
51 #include <sys/prctl.h>
52 #include <sys/timerfd.h>
53 #include <sys/wait.h>
54 
55 #include <linux/bitops.h>
56 #include <linux/hash.h>
57 #include <linux/log2.h>
58 #include <linux/err.h>
59 #include <linux/string.h>
60 #include <linux/time64.h>
61 #include <linux/zalloc.h>
62 #include <perf/evlist.h>
63 #include <perf/evsel.h>
64 #include <perf/cpumap.h>
65 #include <perf/mmap.h>
66 
67 #include <internal/xyarray.h>
68 
69 #ifdef LACKS_SIGQUEUE_PROTOTYPE
70 int sigqueue(pid_t pid, int sig, const union sigval value);
71 #endif
72 
73 #define FD(e, x, y) (*(int *)xyarray__entry(e->core.fd, x, y))
74 #define SID(e, x, y) xyarray__entry(e->core.sample_id, x, y)
75 
76 void evlist__init(struct evlist *evlist, struct perf_cpu_map *cpus,
77 		  struct perf_thread_map *threads)
78 {
79 	perf_evlist__init(&evlist->core);
80 	perf_evlist__set_maps(&evlist->core, cpus, threads);
81 	evlist->workload.pid = -1;
82 	evlist->bkw_mmap_state = BKW_MMAP_NOTREADY;
83 	evlist->ctl_fd.fd = -1;
84 	evlist->ctl_fd.ack = -1;
85 	evlist->ctl_fd.pos = -1;
86 	evlist->nr_br_cntr = -1;
87 	metricgroup__rblist_init(&evlist->metric_events);
88 }
89 
90 struct evlist *evlist__new(void)
91 {
92 	struct evlist *evlist = zalloc(sizeof(*evlist));
93 
94 	if (evlist != NULL)
95 		evlist__init(evlist, NULL, NULL);
96 
97 	return evlist;
98 }
99 
100 struct evlist *evlist__new_default(void)
101 {
102 	struct evlist *evlist = evlist__new();
103 	bool can_profile_kernel;
104 	struct perf_pmu *pmu = NULL;
105 
106 	if (!evlist)
107 		return NULL;
108 
109 	can_profile_kernel = perf_event_paranoid_check(1);
110 
111 	while ((pmu = perf_pmus__scan_core(pmu)) != NULL) {
112 		char buf[256];
113 		int err;
114 
115 		snprintf(buf, sizeof(buf), "%s/cycles/%s", pmu->name,
116 			 can_profile_kernel ? "P" : "Pu");
117 		err = parse_event(evlist, buf);
118 		if (err) {
119 			evlist__delete(evlist);
120 			return NULL;
121 		}
122 	}
123 
124 	if (evlist->core.nr_entries > 1) {
125 		struct evsel *evsel;
126 
127 		evlist__for_each_entry(evlist, evsel)
128 			evsel__set_sample_id(evsel, /*can_sample_identifier=*/false);
129 	}
130 
131 	return evlist;
132 }
133 
134 struct evlist *evlist__new_dummy(void)
135 {
136 	struct evlist *evlist = evlist__new();
137 
138 	if (evlist && evlist__add_dummy(evlist)) {
139 		evlist__delete(evlist);
140 		evlist = NULL;
141 	}
142 
143 	return evlist;
144 }
145 
146 /**
147  * evlist__set_id_pos - set the positions of event ids.
148  * @evlist: selected event list
149  *
150  * Events with compatible sample types all have the same id_pos
151  * and is_pos.  For convenience, put a copy on evlist.
152  */
153 void evlist__set_id_pos(struct evlist *evlist)
154 {
155 	struct evsel *first = evlist__first(evlist);
156 
157 	evlist->id_pos = first->id_pos;
158 	evlist->is_pos = first->is_pos;
159 }
160 
161 static void evlist__update_id_pos(struct evlist *evlist)
162 {
163 	struct evsel *evsel;
164 
165 	evlist__for_each_entry(evlist, evsel)
166 		evsel__calc_id_pos(evsel);
167 
168 	evlist__set_id_pos(evlist);
169 }
170 
171 static void evlist__purge(struct evlist *evlist)
172 {
173 	struct evsel *pos, *n;
174 
175 	evlist__for_each_entry_safe(evlist, n, pos) {
176 		list_del_init(&pos->core.node);
177 		pos->evlist = NULL;
178 		evsel__delete(pos);
179 	}
180 
181 	evlist->core.nr_entries = 0;
182 }
183 
184 void evlist__exit(struct evlist *evlist)
185 {
186 	metricgroup__rblist_exit(&evlist->metric_events);
187 	event_enable_timer__exit(&evlist->eet);
188 	zfree(&evlist->mmap);
189 	zfree(&evlist->overwrite_mmap);
190 	perf_evlist__exit(&evlist->core);
191 }
192 
193 void evlist__delete(struct evlist *evlist)
194 {
195 	if (evlist == NULL)
196 		return;
197 
198 	evlist__free_stats(evlist);
199 	evlist__munmap(evlist);
200 	evlist__close(evlist);
201 	evlist__purge(evlist);
202 	evlist__exit(evlist);
203 	free(evlist);
204 }
205 
206 void evlist__add(struct evlist *evlist, struct evsel *entry)
207 {
208 	perf_evlist__add(&evlist->core, &entry->core);
209 	entry->evlist = evlist;
210 	entry->tracking = !entry->core.idx;
211 
212 	if (evlist->core.nr_entries == 1)
213 		evlist__set_id_pos(evlist);
214 }
215 
216 void evlist__remove(struct evlist *evlist, struct evsel *evsel)
217 {
218 	evsel->evlist = NULL;
219 	perf_evlist__remove(&evlist->core, &evsel->core);
220 }
221 
222 void evlist__splice_list_tail(struct evlist *evlist, struct list_head *list)
223 {
224 	while (!list_empty(list)) {
225 		struct evsel *evsel, *temp, *leader = NULL;
226 
227 		__evlist__for_each_entry_safe(list, temp, evsel) {
228 			list_del_init(&evsel->core.node);
229 			evlist__add(evlist, evsel);
230 			leader = evsel;
231 			break;
232 		}
233 
234 		__evlist__for_each_entry_safe(list, temp, evsel) {
235 			if (evsel__has_leader(evsel, leader)) {
236 				list_del_init(&evsel->core.node);
237 				evlist__add(evlist, evsel);
238 			}
239 		}
240 	}
241 }
242 
243 int __evlist__set_tracepoints_handlers(struct evlist *evlist,
244 				       const struct evsel_str_handler *assocs, size_t nr_assocs)
245 {
246 	size_t i;
247 	int err;
248 
249 	for (i = 0; i < nr_assocs; i++) {
250 		// Adding a handler for an event not in this evlist, just ignore it.
251 		struct evsel *evsel = evlist__find_tracepoint_by_name(evlist, assocs[i].name);
252 		if (evsel == NULL)
253 			continue;
254 
255 		err = -EEXIST;
256 		if (evsel->handler != NULL)
257 			goto out;
258 		evsel->handler = assocs[i].handler;
259 	}
260 
261 	err = 0;
262 out:
263 	return err;
264 }
265 
266 static void evlist__set_leader(struct evlist *evlist)
267 {
268 	perf_evlist__set_leader(&evlist->core);
269 }
270 
271 static struct evsel *evlist__dummy_event(struct evlist *evlist)
272 {
273 	struct perf_event_attr attr = {
274 		.type	= PERF_TYPE_SOFTWARE,
275 		.config = PERF_COUNT_SW_DUMMY,
276 		.size	= sizeof(attr), /* to capture ABI version */
277 		/* Avoid frequency mode for dummy events to avoid associated timers. */
278 		.freq = 0,
279 		.sample_period = 1,
280 	};
281 
282 	return evsel__new_idx(&attr, evlist->core.nr_entries);
283 }
284 
285 int evlist__add_dummy(struct evlist *evlist)
286 {
287 	struct evsel *evsel = evlist__dummy_event(evlist);
288 
289 	if (evsel == NULL)
290 		return -ENOMEM;
291 
292 	evlist__add(evlist, evsel);
293 	return 0;
294 }
295 
296 struct evsel *evlist__add_aux_dummy(struct evlist *evlist, bool system_wide)
297 {
298 	struct evsel *evsel = evlist__dummy_event(evlist);
299 
300 	if (!evsel)
301 		return NULL;
302 
303 	evsel->core.attr.exclude_kernel = 1;
304 	evsel->core.attr.exclude_guest = 1;
305 	evsel->core.attr.exclude_hv = 1;
306 	evsel->core.system_wide = system_wide;
307 	evsel->no_aux_samples = true;
308 	evsel->name = strdup("dummy:u");
309 
310 	evlist__add(evlist, evsel);
311 	return evsel;
312 }
313 
314 #ifdef HAVE_LIBTRACEEVENT
315 struct evsel *evlist__add_sched_switch(struct evlist *evlist, bool system_wide)
316 {
317 	struct evsel *evsel = evsel__newtp_idx("sched", "sched_switch", 0,
318 					       /*format=*/true);
319 
320 	if (IS_ERR(evsel))
321 		return evsel;
322 
323 	evsel__set_sample_bit(evsel, CPU);
324 	evsel__set_sample_bit(evsel, TIME);
325 
326 	evsel->core.system_wide = system_wide;
327 	evsel->no_aux_samples = true;
328 
329 	evlist__add(evlist, evsel);
330 	return evsel;
331 }
332 #endif
333 
334 struct evsel *evlist__find_tracepoint_by_name(struct evlist *evlist, const char *name)
335 {
336 	struct evsel *evsel;
337 
338 	evlist__for_each_entry(evlist, evsel) {
339 		if ((evsel->core.attr.type == PERF_TYPE_TRACEPOINT) &&
340 		    (strcmp(evsel->name, name) == 0))
341 			return evsel;
342 	}
343 
344 	return NULL;
345 }
346 
347 #ifdef HAVE_LIBTRACEEVENT
348 int evlist__add_newtp(struct evlist *evlist, const char *sys, const char *name, void *handler)
349 {
350 	struct evsel *evsel = evsel__newtp(sys, name);
351 
352 	if (IS_ERR(evsel))
353 		return -1;
354 
355 	evsel->handler = handler;
356 	evlist__add(evlist, evsel);
357 	return 0;
358 }
359 #endif
360 
361 struct evlist_cpu_iterator evlist__cpu_begin(struct evlist *evlist, struct affinity *affinity)
362 {
363 	struct evlist_cpu_iterator itr = {
364 		.container = evlist,
365 		.evsel = NULL,
366 		.cpu_map_idx = 0,
367 		.evlist_cpu_map_idx = 0,
368 		.evlist_cpu_map_nr = perf_cpu_map__nr(evlist->core.all_cpus),
369 		.cpu = (struct perf_cpu){ .cpu = -1},
370 		.affinity = affinity,
371 	};
372 
373 	if (evlist__empty(evlist)) {
374 		/* Ensure the empty list doesn't iterate. */
375 		itr.evlist_cpu_map_idx = itr.evlist_cpu_map_nr;
376 	} else {
377 		itr.evsel = evlist__first(evlist);
378 		if (itr.affinity) {
379 			itr.cpu = perf_cpu_map__cpu(evlist->core.all_cpus, 0);
380 			affinity__set(itr.affinity, itr.cpu.cpu);
381 			itr.cpu_map_idx = perf_cpu_map__idx(itr.evsel->core.cpus, itr.cpu);
382 			/*
383 			 * If this CPU isn't in the evsel's cpu map then advance
384 			 * through the list.
385 			 */
386 			if (itr.cpu_map_idx == -1)
387 				evlist_cpu_iterator__next(&itr);
388 		}
389 	}
390 	return itr;
391 }
392 
393 void evlist_cpu_iterator__next(struct evlist_cpu_iterator *evlist_cpu_itr)
394 {
395 	while (evlist_cpu_itr->evsel != evlist__last(evlist_cpu_itr->container)) {
396 		evlist_cpu_itr->evsel = evsel__next(evlist_cpu_itr->evsel);
397 		evlist_cpu_itr->cpu_map_idx =
398 			perf_cpu_map__idx(evlist_cpu_itr->evsel->core.cpus,
399 					  evlist_cpu_itr->cpu);
400 		if (evlist_cpu_itr->cpu_map_idx != -1)
401 			return;
402 	}
403 	evlist_cpu_itr->evlist_cpu_map_idx++;
404 	if (evlist_cpu_itr->evlist_cpu_map_idx < evlist_cpu_itr->evlist_cpu_map_nr) {
405 		evlist_cpu_itr->evsel = evlist__first(evlist_cpu_itr->container);
406 		evlist_cpu_itr->cpu =
407 			perf_cpu_map__cpu(evlist_cpu_itr->container->core.all_cpus,
408 					  evlist_cpu_itr->evlist_cpu_map_idx);
409 		if (evlist_cpu_itr->affinity)
410 			affinity__set(evlist_cpu_itr->affinity, evlist_cpu_itr->cpu.cpu);
411 		evlist_cpu_itr->cpu_map_idx =
412 			perf_cpu_map__idx(evlist_cpu_itr->evsel->core.cpus,
413 					  evlist_cpu_itr->cpu);
414 		/*
415 		 * If this CPU isn't in the evsel's cpu map then advance through
416 		 * the list.
417 		 */
418 		if (evlist_cpu_itr->cpu_map_idx == -1)
419 			evlist_cpu_iterator__next(evlist_cpu_itr);
420 	}
421 }
422 
423 bool evlist_cpu_iterator__end(const struct evlist_cpu_iterator *evlist_cpu_itr)
424 {
425 	return evlist_cpu_itr->evlist_cpu_map_idx >= evlist_cpu_itr->evlist_cpu_map_nr;
426 }
427 
428 static int evsel__strcmp(struct evsel *pos, char *evsel_name)
429 {
430 	if (!evsel_name)
431 		return 0;
432 	if (evsel__is_dummy_event(pos))
433 		return 1;
434 	return !evsel__name_is(pos, evsel_name);
435 }
436 
437 static int evlist__is_enabled(struct evlist *evlist)
438 {
439 	struct evsel *pos;
440 
441 	evlist__for_each_entry(evlist, pos) {
442 		if (!evsel__is_group_leader(pos) || !pos->core.fd)
443 			continue;
444 		/* If at least one event is enabled, evlist is enabled. */
445 		if (!pos->disabled)
446 			return true;
447 	}
448 	return false;
449 }
450 
451 static void __evlist__disable(struct evlist *evlist, char *evsel_name, bool excl_dummy)
452 {
453 	struct evsel *pos;
454 	struct evlist_cpu_iterator evlist_cpu_itr;
455 	struct affinity saved_affinity, *affinity = NULL;
456 	bool has_imm = false;
457 
458 	// See explanation in evlist__close()
459 	if (!cpu_map__is_dummy(evlist->core.user_requested_cpus)) {
460 		if (affinity__setup(&saved_affinity) < 0)
461 			return;
462 		affinity = &saved_affinity;
463 	}
464 
465 	/* Disable 'immediate' events last */
466 	for (int imm = 0; imm <= 1; imm++) {
467 		evlist__for_each_cpu(evlist_cpu_itr, evlist, affinity) {
468 			pos = evlist_cpu_itr.evsel;
469 			if (evsel__strcmp(pos, evsel_name))
470 				continue;
471 			if (pos->disabled || !evsel__is_group_leader(pos) || !pos->core.fd)
472 				continue;
473 			if (excl_dummy && evsel__is_dummy_event(pos))
474 				continue;
475 			if (pos->immediate)
476 				has_imm = true;
477 			if (pos->immediate != imm)
478 				continue;
479 			evsel__disable_cpu(pos, evlist_cpu_itr.cpu_map_idx);
480 		}
481 		if (!has_imm)
482 			break;
483 	}
484 
485 	affinity__cleanup(affinity);
486 	evlist__for_each_entry(evlist, pos) {
487 		if (evsel__strcmp(pos, evsel_name))
488 			continue;
489 		if (!evsel__is_group_leader(pos) || !pos->core.fd)
490 			continue;
491 		if (excl_dummy && evsel__is_dummy_event(pos))
492 			continue;
493 		pos->disabled = true;
494 	}
495 
496 	/*
497 	 * If we disabled only single event, we need to check
498 	 * the enabled state of the evlist manually.
499 	 */
500 	if (evsel_name)
501 		evlist->enabled = evlist__is_enabled(evlist);
502 	else
503 		evlist->enabled = false;
504 }
505 
506 void evlist__disable(struct evlist *evlist)
507 {
508 	__evlist__disable(evlist, NULL, false);
509 }
510 
511 void evlist__disable_non_dummy(struct evlist *evlist)
512 {
513 	__evlist__disable(evlist, NULL, true);
514 }
515 
516 void evlist__disable_evsel(struct evlist *evlist, char *evsel_name)
517 {
518 	__evlist__disable(evlist, evsel_name, false);
519 }
520 
521 static void __evlist__enable(struct evlist *evlist, char *evsel_name, bool excl_dummy)
522 {
523 	struct evsel *pos;
524 	struct evlist_cpu_iterator evlist_cpu_itr;
525 	struct affinity saved_affinity, *affinity = NULL;
526 
527 	// See explanation in evlist__close()
528 	if (!cpu_map__is_dummy(evlist->core.user_requested_cpus)) {
529 		if (affinity__setup(&saved_affinity) < 0)
530 			return;
531 		affinity = &saved_affinity;
532 	}
533 
534 	evlist__for_each_cpu(evlist_cpu_itr, evlist, affinity) {
535 		pos = evlist_cpu_itr.evsel;
536 		if (evsel__strcmp(pos, evsel_name))
537 			continue;
538 		if (!evsel__is_group_leader(pos) || !pos->core.fd)
539 			continue;
540 		if (excl_dummy && evsel__is_dummy_event(pos))
541 			continue;
542 		evsel__enable_cpu(pos, evlist_cpu_itr.cpu_map_idx);
543 	}
544 	affinity__cleanup(affinity);
545 	evlist__for_each_entry(evlist, pos) {
546 		if (evsel__strcmp(pos, evsel_name))
547 			continue;
548 		if (!evsel__is_group_leader(pos) || !pos->core.fd)
549 			continue;
550 		if (excl_dummy && evsel__is_dummy_event(pos))
551 			continue;
552 		pos->disabled = false;
553 	}
554 
555 	/*
556 	 * Even single event sets the 'enabled' for evlist,
557 	 * so the toggle can work properly and toggle to
558 	 * 'disabled' state.
559 	 */
560 	evlist->enabled = true;
561 }
562 
563 void evlist__enable(struct evlist *evlist)
564 {
565 	__evlist__enable(evlist, NULL, false);
566 }
567 
568 void evlist__enable_non_dummy(struct evlist *evlist)
569 {
570 	__evlist__enable(evlist, NULL, true);
571 }
572 
573 void evlist__enable_evsel(struct evlist *evlist, char *evsel_name)
574 {
575 	__evlist__enable(evlist, evsel_name, false);
576 }
577 
578 void evlist__toggle_enable(struct evlist *evlist)
579 {
580 	(evlist->enabled ? evlist__disable : evlist__enable)(evlist);
581 }
582 
583 int evlist__add_pollfd(struct evlist *evlist, int fd)
584 {
585 	return perf_evlist__add_pollfd(&evlist->core, fd, NULL, POLLIN, fdarray_flag__default);
586 }
587 
588 int evlist__filter_pollfd(struct evlist *evlist, short revents_and_mask)
589 {
590 	return perf_evlist__filter_pollfd(&evlist->core, revents_and_mask);
591 }
592 
593 #ifdef HAVE_EVENTFD_SUPPORT
594 int evlist__add_wakeup_eventfd(struct evlist *evlist, int fd)
595 {
596 	return perf_evlist__add_pollfd(&evlist->core, fd, NULL, POLLIN,
597 				       fdarray_flag__nonfilterable |
598 				       fdarray_flag__non_perf_event);
599 }
600 #endif
601 
602 int evlist__poll(struct evlist *evlist, int timeout)
603 {
604 	return perf_evlist__poll(&evlist->core, timeout);
605 }
606 
607 struct perf_sample_id *evlist__id2sid(struct evlist *evlist, u64 id)
608 {
609 	struct hlist_head *head;
610 	struct perf_sample_id *sid;
611 	int hash;
612 
613 	hash = hash_64(id, PERF_EVLIST__HLIST_BITS);
614 	head = &evlist->core.heads[hash];
615 
616 	hlist_for_each_entry(sid, head, node)
617 		if (sid->id == id)
618 			return sid;
619 
620 	return NULL;
621 }
622 
623 struct evsel *evlist__id2evsel(struct evlist *evlist, u64 id)
624 {
625 	struct perf_sample_id *sid;
626 
627 	if (evlist->core.nr_entries == 1 || !id)
628 		return evlist__first(evlist);
629 
630 	sid = evlist__id2sid(evlist, id);
631 	if (sid)
632 		return container_of(sid->evsel, struct evsel, core);
633 
634 	if (!evlist__sample_id_all(evlist))
635 		return evlist__first(evlist);
636 
637 	return NULL;
638 }
639 
640 struct evsel *evlist__id2evsel_strict(struct evlist *evlist, u64 id)
641 {
642 	struct perf_sample_id *sid;
643 
644 	if (!id)
645 		return NULL;
646 
647 	sid = evlist__id2sid(evlist, id);
648 	if (sid)
649 		return container_of(sid->evsel, struct evsel, core);
650 
651 	return NULL;
652 }
653 
654 static int evlist__event2id(struct evlist *evlist, union perf_event *event, u64 *id)
655 {
656 	const __u64 *array = event->sample.array;
657 	ssize_t n;
658 
659 	n = (event->header.size - sizeof(event->header)) >> 3;
660 
661 	if (event->header.type == PERF_RECORD_SAMPLE) {
662 		if (evlist->id_pos >= n)
663 			return -1;
664 		*id = array[evlist->id_pos];
665 	} else {
666 		if (evlist->is_pos > n)
667 			return -1;
668 		n -= evlist->is_pos;
669 		*id = array[n];
670 	}
671 	return 0;
672 }
673 
674 struct evsel *evlist__event2evsel(struct evlist *evlist, union perf_event *event)
675 {
676 	struct evsel *first = evlist__first(evlist);
677 	struct hlist_head *head;
678 	struct perf_sample_id *sid;
679 	int hash;
680 	u64 id;
681 
682 	if (evlist->core.nr_entries == 1)
683 		return first;
684 
685 	if (!first->core.attr.sample_id_all &&
686 	    event->header.type != PERF_RECORD_SAMPLE)
687 		return first;
688 
689 	if (evlist__event2id(evlist, event, &id))
690 		return NULL;
691 
692 	/* Synthesized events have an id of zero */
693 	if (!id)
694 		return first;
695 
696 	hash = hash_64(id, PERF_EVLIST__HLIST_BITS);
697 	head = &evlist->core.heads[hash];
698 
699 	hlist_for_each_entry(sid, head, node) {
700 		if (sid->id == id)
701 			return container_of(sid->evsel, struct evsel, core);
702 	}
703 	return NULL;
704 }
705 
706 static int evlist__set_paused(struct evlist *evlist, bool value)
707 {
708 	int i;
709 
710 	if (!evlist->overwrite_mmap)
711 		return 0;
712 
713 	for (i = 0; i < evlist->core.nr_mmaps; i++) {
714 		int fd = evlist->overwrite_mmap[i].core.fd;
715 		int err;
716 
717 		if (fd < 0)
718 			continue;
719 		err = ioctl(fd, PERF_EVENT_IOC_PAUSE_OUTPUT, value ? 1 : 0);
720 		if (err)
721 			return err;
722 	}
723 	return 0;
724 }
725 
726 static int evlist__pause(struct evlist *evlist)
727 {
728 	return evlist__set_paused(evlist, true);
729 }
730 
731 static int evlist__resume(struct evlist *evlist)
732 {
733 	return evlist__set_paused(evlist, false);
734 }
735 
736 static void evlist__munmap_nofree(struct evlist *evlist)
737 {
738 	int i;
739 
740 	if (evlist->mmap)
741 		for (i = 0; i < evlist->core.nr_mmaps; i++)
742 			perf_mmap__munmap(&evlist->mmap[i].core);
743 
744 	if (evlist->overwrite_mmap)
745 		for (i = 0; i < evlist->core.nr_mmaps; i++)
746 			perf_mmap__munmap(&evlist->overwrite_mmap[i].core);
747 }
748 
749 void evlist__munmap(struct evlist *evlist)
750 {
751 	evlist__munmap_nofree(evlist);
752 	zfree(&evlist->mmap);
753 	zfree(&evlist->overwrite_mmap);
754 }
755 
756 static void perf_mmap__unmap_cb(struct perf_mmap *map)
757 {
758 	struct mmap *m = container_of(map, struct mmap, core);
759 
760 	mmap__munmap(m);
761 }
762 
763 static struct mmap *evlist__alloc_mmap(struct evlist *evlist,
764 				       bool overwrite)
765 {
766 	int i;
767 	struct mmap *map;
768 
769 	map = zalloc(evlist->core.nr_mmaps * sizeof(struct mmap));
770 	if (!map)
771 		return NULL;
772 
773 	for (i = 0; i < evlist->core.nr_mmaps; i++) {
774 		struct perf_mmap *prev = i ? &map[i - 1].core : NULL;
775 
776 		/*
777 		 * When the perf_mmap() call is made we grab one refcount, plus
778 		 * one extra to let perf_mmap__consume() get the last
779 		 * events after all real references (perf_mmap__get()) are
780 		 * dropped.
781 		 *
782 		 * Each PERF_EVENT_IOC_SET_OUTPUT points to this mmap and
783 		 * thus does perf_mmap__get() on it.
784 		 */
785 		perf_mmap__init(&map[i].core, prev, overwrite, perf_mmap__unmap_cb);
786 	}
787 
788 	return map;
789 }
790 
791 static void
792 perf_evlist__mmap_cb_idx(struct perf_evlist *_evlist,
793 			 struct perf_evsel *_evsel,
794 			 struct perf_mmap_param *_mp,
795 			 int idx)
796 {
797 	struct evlist *evlist = container_of(_evlist, struct evlist, core);
798 	struct mmap_params *mp = container_of(_mp, struct mmap_params, core);
799 	struct evsel *evsel = container_of(_evsel, struct evsel, core);
800 
801 	auxtrace_mmap_params__set_idx(&mp->auxtrace_mp, evlist, evsel, idx);
802 }
803 
804 static struct perf_mmap*
805 perf_evlist__mmap_cb_get(struct perf_evlist *_evlist, bool overwrite, int idx)
806 {
807 	struct evlist *evlist = container_of(_evlist, struct evlist, core);
808 	struct mmap *maps;
809 
810 	maps = overwrite ? evlist->overwrite_mmap : evlist->mmap;
811 
812 	if (!maps) {
813 		maps = evlist__alloc_mmap(evlist, overwrite);
814 		if (!maps)
815 			return NULL;
816 
817 		if (overwrite) {
818 			evlist->overwrite_mmap = maps;
819 			if (evlist->bkw_mmap_state == BKW_MMAP_NOTREADY)
820 				evlist__toggle_bkw_mmap(evlist, BKW_MMAP_RUNNING);
821 		} else {
822 			evlist->mmap = maps;
823 		}
824 	}
825 
826 	return &maps[idx].core;
827 }
828 
829 static int
830 perf_evlist__mmap_cb_mmap(struct perf_mmap *_map, struct perf_mmap_param *_mp,
831 			  int output, struct perf_cpu cpu)
832 {
833 	struct mmap *map = container_of(_map, struct mmap, core);
834 	struct mmap_params *mp = container_of(_mp, struct mmap_params, core);
835 
836 	return mmap__mmap(map, mp, output, cpu);
837 }
838 
839 unsigned long perf_event_mlock_kb_in_pages(void)
840 {
841 	unsigned long pages;
842 	int max;
843 
844 	if (sysctl__read_int("kernel/perf_event_mlock_kb", &max) < 0) {
845 		/*
846 		 * Pick a once upon a time good value, i.e. things look
847 		 * strange since we can't read a sysctl value, but lets not
848 		 * die yet...
849 		 */
850 		max = 512;
851 	} else {
852 		max -= (page_size / 1024);
853 	}
854 
855 	pages = (max * 1024) / page_size;
856 	if (!is_power_of_2(pages))
857 		pages = rounddown_pow_of_two(pages);
858 
859 	return pages;
860 }
861 
862 size_t evlist__mmap_size(unsigned long pages)
863 {
864 	if (pages == UINT_MAX)
865 		pages = perf_event_mlock_kb_in_pages();
866 	else if (!is_power_of_2(pages))
867 		return 0;
868 
869 	return (pages + 1) * page_size;
870 }
871 
872 static long parse_pages_arg(const char *str, unsigned long min,
873 			    unsigned long max)
874 {
875 	unsigned long pages, val;
876 	static struct parse_tag tags[] = {
877 		{ .tag  = 'B', .mult = 1       },
878 		{ .tag  = 'K', .mult = 1 << 10 },
879 		{ .tag  = 'M', .mult = 1 << 20 },
880 		{ .tag  = 'G', .mult = 1 << 30 },
881 		{ .tag  = 0 },
882 	};
883 
884 	if (str == NULL)
885 		return -EINVAL;
886 
887 	val = parse_tag_value(str, tags);
888 	if (val != (unsigned long) -1) {
889 		/* we got file size value */
890 		pages = PERF_ALIGN(val, page_size) / page_size;
891 	} else {
892 		/* we got pages count value */
893 		char *eptr;
894 		pages = strtoul(str, &eptr, 10);
895 		if (*eptr != '\0')
896 			return -EINVAL;
897 	}
898 
899 	if (pages == 0 && min == 0) {
900 		/* leave number of pages at 0 */
901 	} else if (!is_power_of_2(pages)) {
902 		char buf[100];
903 
904 		/* round pages up to next power of 2 */
905 		pages = roundup_pow_of_two(pages);
906 		if (!pages)
907 			return -EINVAL;
908 
909 		unit_number__scnprintf(buf, sizeof(buf), pages * page_size);
910 		pr_info("rounding mmap pages size to %s (%lu pages)\n",
911 			buf, pages);
912 	}
913 
914 	if (pages > max)
915 		return -EINVAL;
916 
917 	return pages;
918 }
919 
920 int __evlist__parse_mmap_pages(unsigned int *mmap_pages, const char *str)
921 {
922 	unsigned long max = UINT_MAX;
923 	long pages;
924 
925 	if (max > SIZE_MAX / page_size)
926 		max = SIZE_MAX / page_size;
927 
928 	pages = parse_pages_arg(str, 1, max);
929 	if (pages < 0) {
930 		pr_err("Invalid argument for --mmap_pages/-m\n");
931 		return -1;
932 	}
933 
934 	*mmap_pages = pages;
935 	return 0;
936 }
937 
938 int evlist__parse_mmap_pages(const struct option *opt, const char *str, int unset __maybe_unused)
939 {
940 	return __evlist__parse_mmap_pages(opt->value, str);
941 }
942 
943 /**
944  * evlist__mmap_ex - Create mmaps to receive events.
945  * @evlist: list of events
946  * @pages: map length in pages
947  * @overwrite: overwrite older events?
948  * @auxtrace_pages - auxtrace map length in pages
949  * @auxtrace_overwrite - overwrite older auxtrace data?
950  *
951  * If @overwrite is %false the user needs to signal event consumption using
952  * perf_mmap__write_tail().  Using evlist__mmap_read() does this
953  * automatically.
954  *
955  * Similarly, if @auxtrace_overwrite is %false the user needs to signal data
956  * consumption using auxtrace_mmap__write_tail().
957  *
958  * Return: %0 on success, negative error code otherwise.
959  */
960 int evlist__mmap_ex(struct evlist *evlist, unsigned int pages,
961 			 unsigned int auxtrace_pages,
962 			 bool auxtrace_overwrite, int nr_cblocks, int affinity, int flush,
963 			 int comp_level)
964 {
965 	/*
966 	 * Delay setting mp.prot: set it before calling perf_mmap__mmap.
967 	 * Its value is decided by evsel's write_backward.
968 	 * So &mp should not be passed through const pointer.
969 	 */
970 	struct mmap_params mp = {
971 		.nr_cblocks	= nr_cblocks,
972 		.affinity	= affinity,
973 		.flush		= flush,
974 		.comp_level	= comp_level
975 	};
976 	struct perf_evlist_mmap_ops ops = {
977 		.idx  = perf_evlist__mmap_cb_idx,
978 		.get  = perf_evlist__mmap_cb_get,
979 		.mmap = perf_evlist__mmap_cb_mmap,
980 	};
981 
982 	evlist->core.mmap_len = evlist__mmap_size(pages);
983 	pr_debug("mmap size %zuB\n", evlist->core.mmap_len);
984 
985 	auxtrace_mmap_params__init(&mp.auxtrace_mp, evlist->core.mmap_len,
986 				   auxtrace_pages, auxtrace_overwrite);
987 
988 	return perf_evlist__mmap_ops(&evlist->core, &ops, &mp.core);
989 }
990 
991 int evlist__mmap(struct evlist *evlist, unsigned int pages)
992 {
993 	return evlist__mmap_ex(evlist, pages, 0, false, 0, PERF_AFFINITY_SYS, 1, 0);
994 }
995 
996 int evlist__create_maps(struct evlist *evlist, struct target *target)
997 {
998 	bool all_threads = (target->per_thread && target->system_wide);
999 	struct perf_cpu_map *cpus;
1000 	struct perf_thread_map *threads;
1001 
1002 	/*
1003 	 * If specify '-a' and '--per-thread' to perf record, perf record
1004 	 * will override '--per-thread'. target->per_thread = false and
1005 	 * target->system_wide = true.
1006 	 *
1007 	 * If specify '--per-thread' only to perf record,
1008 	 * target->per_thread = true and target->system_wide = false.
1009 	 *
1010 	 * So target->per_thread && target->system_wide is false.
1011 	 * For perf record, thread_map__new_str doesn't call
1012 	 * thread_map__new_all_cpus. That will keep perf record's
1013 	 * current behavior.
1014 	 *
1015 	 * For perf stat, it allows the case that target->per_thread and
1016 	 * target->system_wide are all true. It means to collect system-wide
1017 	 * per-thread data. thread_map__new_str will call
1018 	 * thread_map__new_all_cpus to enumerate all threads.
1019 	 */
1020 	threads = thread_map__new_str(target->pid, target->tid, all_threads);
1021 
1022 	if (!threads)
1023 		return -1;
1024 
1025 	if (target__uses_dummy_map(target) && !evlist__has_bpf_output(evlist))
1026 		cpus = perf_cpu_map__new_any_cpu();
1027 	else
1028 		cpus = perf_cpu_map__new(target->cpu_list);
1029 
1030 	if (!cpus)
1031 		goto out_delete_threads;
1032 
1033 	evlist->core.has_user_cpus = !!target->cpu_list;
1034 
1035 	perf_evlist__set_maps(&evlist->core, cpus, threads);
1036 
1037 	/* as evlist now has references, put count here */
1038 	perf_cpu_map__put(cpus);
1039 	perf_thread_map__put(threads);
1040 
1041 	return 0;
1042 
1043 out_delete_threads:
1044 	perf_thread_map__put(threads);
1045 	return -1;
1046 }
1047 
1048 int evlist__apply_filters(struct evlist *evlist, struct evsel **err_evsel,
1049 			  struct target *target)
1050 {
1051 	struct evsel *evsel;
1052 	int err = 0;
1053 
1054 	evlist__for_each_entry(evlist, evsel) {
1055 		/*
1056 		 * filters only work for tracepoint event, which doesn't have cpu limit.
1057 		 * So evlist and evsel should always be same.
1058 		 */
1059 		if (evsel->filter) {
1060 			err = perf_evsel__apply_filter(&evsel->core, evsel->filter);
1061 			if (err) {
1062 				*err_evsel = evsel;
1063 				break;
1064 			}
1065 		}
1066 
1067 		/*
1068 		 * non-tracepoint events can have BPF filters.
1069 		 */
1070 		if (!list_empty(&evsel->bpf_filters)) {
1071 			err = perf_bpf_filter__prepare(evsel, target);
1072 			if (err) {
1073 				*err_evsel = evsel;
1074 				break;
1075 			}
1076 		}
1077 	}
1078 
1079 	return err;
1080 }
1081 
1082 int evlist__set_tp_filter(struct evlist *evlist, const char *filter)
1083 {
1084 	struct evsel *evsel;
1085 	int err = 0;
1086 
1087 	if (filter == NULL)
1088 		return -1;
1089 
1090 	evlist__for_each_entry(evlist, evsel) {
1091 		if (evsel->core.attr.type != PERF_TYPE_TRACEPOINT)
1092 			continue;
1093 
1094 		err = evsel__set_filter(evsel, filter);
1095 		if (err)
1096 			break;
1097 	}
1098 
1099 	return err;
1100 }
1101 
1102 int evlist__append_tp_filter(struct evlist *evlist, const char *filter)
1103 {
1104 	struct evsel *evsel;
1105 	int err = 0;
1106 
1107 	if (filter == NULL)
1108 		return -1;
1109 
1110 	evlist__for_each_entry(evlist, evsel) {
1111 		if (evsel->core.attr.type != PERF_TYPE_TRACEPOINT)
1112 			continue;
1113 
1114 		err = evsel__append_tp_filter(evsel, filter);
1115 		if (err)
1116 			break;
1117 	}
1118 
1119 	return err;
1120 }
1121 
1122 char *asprintf__tp_filter_pids(size_t npids, pid_t *pids)
1123 {
1124 	char *filter;
1125 	size_t i;
1126 
1127 	for (i = 0; i < npids; ++i) {
1128 		if (i == 0) {
1129 			if (asprintf(&filter, "common_pid != %d", pids[i]) < 0)
1130 				return NULL;
1131 		} else {
1132 			char *tmp;
1133 
1134 			if (asprintf(&tmp, "%s && common_pid != %d", filter, pids[i]) < 0)
1135 				goto out_free;
1136 
1137 			free(filter);
1138 			filter = tmp;
1139 		}
1140 	}
1141 
1142 	return filter;
1143 out_free:
1144 	free(filter);
1145 	return NULL;
1146 }
1147 
1148 int evlist__set_tp_filter_pids(struct evlist *evlist, size_t npids, pid_t *pids)
1149 {
1150 	char *filter = asprintf__tp_filter_pids(npids, pids);
1151 	int ret = evlist__set_tp_filter(evlist, filter);
1152 
1153 	free(filter);
1154 	return ret;
1155 }
1156 
1157 int evlist__append_tp_filter_pids(struct evlist *evlist, size_t npids, pid_t *pids)
1158 {
1159 	char *filter = asprintf__tp_filter_pids(npids, pids);
1160 	int ret = evlist__append_tp_filter(evlist, filter);
1161 
1162 	free(filter);
1163 	return ret;
1164 }
1165 
1166 int evlist__append_tp_filter_pid(struct evlist *evlist, pid_t pid)
1167 {
1168 	return evlist__append_tp_filter_pids(evlist, 1, &pid);
1169 }
1170 
1171 bool evlist__valid_sample_type(struct evlist *evlist)
1172 {
1173 	struct evsel *pos;
1174 
1175 	if (evlist->core.nr_entries == 1)
1176 		return true;
1177 
1178 	if (evlist->id_pos < 0 || evlist->is_pos < 0)
1179 		return false;
1180 
1181 	evlist__for_each_entry(evlist, pos) {
1182 		if (pos->id_pos != evlist->id_pos ||
1183 		    pos->is_pos != evlist->is_pos)
1184 			return false;
1185 	}
1186 
1187 	return true;
1188 }
1189 
1190 u64 __evlist__combined_sample_type(struct evlist *evlist)
1191 {
1192 	struct evsel *evsel;
1193 
1194 	if (evlist->combined_sample_type)
1195 		return evlist->combined_sample_type;
1196 
1197 	evlist__for_each_entry(evlist, evsel)
1198 		evlist->combined_sample_type |= evsel->core.attr.sample_type;
1199 
1200 	return evlist->combined_sample_type;
1201 }
1202 
1203 u64 evlist__combined_sample_type(struct evlist *evlist)
1204 {
1205 	evlist->combined_sample_type = 0;
1206 	return __evlist__combined_sample_type(evlist);
1207 }
1208 
1209 u64 evlist__combined_branch_type(struct evlist *evlist)
1210 {
1211 	struct evsel *evsel;
1212 	u64 branch_type = 0;
1213 
1214 	evlist__for_each_entry(evlist, evsel)
1215 		branch_type |= evsel->core.attr.branch_sample_type;
1216 	return branch_type;
1217 }
1218 
1219 static struct evsel *
1220 evlist__find_dup_event_from_prev(struct evlist *evlist, struct evsel *event)
1221 {
1222 	struct evsel *pos;
1223 
1224 	evlist__for_each_entry(evlist, pos) {
1225 		if (event == pos)
1226 			break;
1227 		if ((pos->core.attr.branch_sample_type & PERF_SAMPLE_BRANCH_COUNTERS) &&
1228 		    !strcmp(pos->name, event->name))
1229 			return pos;
1230 	}
1231 	return NULL;
1232 }
1233 
1234 #define MAX_NR_ABBR_NAME	(26 * 11)
1235 
1236 /*
1237  * The abbr name is from A to Z9. If the number of event
1238  * which requires the branch counter > MAX_NR_ABBR_NAME,
1239  * return NA.
1240  */
1241 static void evlist__new_abbr_name(char *name)
1242 {
1243 	static int idx;
1244 	int i = idx / 26;
1245 
1246 	if (idx >= MAX_NR_ABBR_NAME) {
1247 		name[0] = 'N';
1248 		name[1] = 'A';
1249 		name[2] = '\0';
1250 		return;
1251 	}
1252 
1253 	name[0] = 'A' + (idx % 26);
1254 
1255 	if (!i)
1256 		name[1] = '\0';
1257 	else {
1258 		name[1] = '0' + i - 1;
1259 		name[2] = '\0';
1260 	}
1261 
1262 	idx++;
1263 }
1264 
1265 void evlist__update_br_cntr(struct evlist *evlist)
1266 {
1267 	struct evsel *evsel, *dup;
1268 	int i = 0;
1269 
1270 	evlist__for_each_entry(evlist, evsel) {
1271 		if (evsel->core.attr.branch_sample_type & PERF_SAMPLE_BRANCH_COUNTERS) {
1272 			evsel->br_cntr_idx = i++;
1273 			evsel__leader(evsel)->br_cntr_nr++;
1274 
1275 			dup = evlist__find_dup_event_from_prev(evlist, evsel);
1276 			if (dup)
1277 				memcpy(evsel->abbr_name, dup->abbr_name, 3 * sizeof(char));
1278 			else
1279 				evlist__new_abbr_name(evsel->abbr_name);
1280 		}
1281 	}
1282 	evlist->nr_br_cntr = i;
1283 }
1284 
1285 bool evlist__valid_read_format(struct evlist *evlist)
1286 {
1287 	struct evsel *first = evlist__first(evlist), *pos = first;
1288 	u64 read_format = first->core.attr.read_format;
1289 	u64 sample_type = first->core.attr.sample_type;
1290 
1291 	evlist__for_each_entry(evlist, pos) {
1292 		if (read_format != pos->core.attr.read_format) {
1293 			pr_debug("Read format differs %#" PRIx64 " vs %#" PRIx64 "\n",
1294 				 read_format, (u64)pos->core.attr.read_format);
1295 		}
1296 	}
1297 
1298 	/* PERF_SAMPLE_READ implies PERF_FORMAT_ID. */
1299 	if ((sample_type & PERF_SAMPLE_READ) &&
1300 	    !(read_format & PERF_FORMAT_ID)) {
1301 		return false;
1302 	}
1303 
1304 	return true;
1305 }
1306 
1307 u16 evlist__id_hdr_size(struct evlist *evlist)
1308 {
1309 	struct evsel *first = evlist__first(evlist);
1310 
1311 	return first->core.attr.sample_id_all ? evsel__id_hdr_size(first) : 0;
1312 }
1313 
1314 bool evlist__valid_sample_id_all(struct evlist *evlist)
1315 {
1316 	struct evsel *first = evlist__first(evlist), *pos = first;
1317 
1318 	evlist__for_each_entry_continue(evlist, pos) {
1319 		if (first->core.attr.sample_id_all != pos->core.attr.sample_id_all)
1320 			return false;
1321 	}
1322 
1323 	return true;
1324 }
1325 
1326 bool evlist__sample_id_all(struct evlist *evlist)
1327 {
1328 	struct evsel *first = evlist__first(evlist);
1329 	return first->core.attr.sample_id_all;
1330 }
1331 
1332 void evlist__set_selected(struct evlist *evlist, struct evsel *evsel)
1333 {
1334 	evlist->selected = evsel;
1335 }
1336 
1337 void evlist__close(struct evlist *evlist)
1338 {
1339 	struct evsel *evsel;
1340 	struct evlist_cpu_iterator evlist_cpu_itr;
1341 	struct affinity affinity;
1342 
1343 	/*
1344 	 * With perf record core.user_requested_cpus is usually NULL.
1345 	 * Use the old method to handle this for now.
1346 	 */
1347 	if (!evlist->core.user_requested_cpus ||
1348 	    cpu_map__is_dummy(evlist->core.user_requested_cpus)) {
1349 		evlist__for_each_entry_reverse(evlist, evsel)
1350 			evsel__close(evsel);
1351 		return;
1352 	}
1353 
1354 	if (affinity__setup(&affinity) < 0)
1355 		return;
1356 
1357 	evlist__for_each_cpu(evlist_cpu_itr, evlist, &affinity) {
1358 		perf_evsel__close_cpu(&evlist_cpu_itr.evsel->core,
1359 				      evlist_cpu_itr.cpu_map_idx);
1360 	}
1361 
1362 	affinity__cleanup(&affinity);
1363 	evlist__for_each_entry_reverse(evlist, evsel) {
1364 		perf_evsel__free_fd(&evsel->core);
1365 		perf_evsel__free_id(&evsel->core);
1366 	}
1367 	perf_evlist__reset_id_hash(&evlist->core);
1368 }
1369 
1370 static int evlist__create_syswide_maps(struct evlist *evlist)
1371 {
1372 	struct perf_cpu_map *cpus;
1373 	struct perf_thread_map *threads;
1374 
1375 	/*
1376 	 * Try reading /sys/devices/system/cpu/online to get
1377 	 * an all cpus map.
1378 	 *
1379 	 * FIXME: -ENOMEM is the best we can do here, the cpu_map
1380 	 * code needs an overhaul to properly forward the
1381 	 * error, and we may not want to do that fallback to a
1382 	 * default cpu identity map :-\
1383 	 */
1384 	cpus = perf_cpu_map__new_online_cpus();
1385 	if (!cpus)
1386 		return -ENOMEM;
1387 
1388 	threads = perf_thread_map__new_dummy();
1389 	if (!threads) {
1390 		perf_cpu_map__put(cpus);
1391 		return -ENOMEM;
1392 	}
1393 
1394 	perf_evlist__set_maps(&evlist->core, cpus, threads);
1395 	perf_thread_map__put(threads);
1396 	perf_cpu_map__put(cpus);
1397 	return 0;
1398 }
1399 
1400 int evlist__open(struct evlist *evlist)
1401 {
1402 	struct evsel *evsel;
1403 	int err;
1404 
1405 	/*
1406 	 * Default: one fd per CPU, all threads, aka systemwide
1407 	 * as sys_perf_event_open(cpu = -1, thread = -1) is EINVAL
1408 	 */
1409 	if (evlist->core.threads == NULL && evlist->core.user_requested_cpus == NULL) {
1410 		err = evlist__create_syswide_maps(evlist);
1411 		if (err < 0)
1412 			goto out_err;
1413 	}
1414 
1415 	evlist__update_id_pos(evlist);
1416 
1417 	evlist__for_each_entry(evlist, evsel) {
1418 		err = evsel__open(evsel, evsel->core.cpus, evsel->core.threads);
1419 		if (err < 0)
1420 			goto out_err;
1421 	}
1422 
1423 	return 0;
1424 out_err:
1425 	evlist__close(evlist);
1426 	errno = -err;
1427 	return err;
1428 }
1429 
1430 int evlist__prepare_workload(struct evlist *evlist, struct target *target, const char *argv[],
1431 			     bool pipe_output, void (*exec_error)(int signo, siginfo_t *info, void *ucontext))
1432 {
1433 	int child_ready_pipe[2], go_pipe[2];
1434 	char bf;
1435 
1436 	evlist->workload.cork_fd = -1;
1437 
1438 	if (pipe(child_ready_pipe) < 0) {
1439 		perror("failed to create 'ready' pipe");
1440 		return -1;
1441 	}
1442 
1443 	if (pipe(go_pipe) < 0) {
1444 		perror("failed to create 'go' pipe");
1445 		goto out_close_ready_pipe;
1446 	}
1447 
1448 	evlist->workload.pid = fork();
1449 	if (evlist->workload.pid < 0) {
1450 		perror("failed to fork");
1451 		goto out_close_pipes;
1452 	}
1453 
1454 	if (!evlist->workload.pid) {
1455 		int ret;
1456 
1457 		if (pipe_output)
1458 			dup2(2, 1);
1459 
1460 		signal(SIGTERM, SIG_DFL);
1461 
1462 		close(child_ready_pipe[0]);
1463 		close(go_pipe[1]);
1464 		fcntl(go_pipe[0], F_SETFD, FD_CLOEXEC);
1465 
1466 		/*
1467 		 * Change the name of this process not to confuse --exclude-perf users
1468 		 * that sees 'perf' in the window up to the execvp() and thinks that
1469 		 * perf samples are not being excluded.
1470 		 */
1471 		prctl(PR_SET_NAME, "perf-exec");
1472 
1473 		/*
1474 		 * Tell the parent we're ready to go
1475 		 */
1476 		close(child_ready_pipe[1]);
1477 
1478 		/*
1479 		 * Wait until the parent tells us to go.
1480 		 */
1481 		ret = read(go_pipe[0], &bf, 1);
1482 		/*
1483 		 * The parent will ask for the execvp() to be performed by
1484 		 * writing exactly one byte, in workload.cork_fd, usually via
1485 		 * evlist__start_workload().
1486 		 *
1487 		 * For cancelling the workload without actually running it,
1488 		 * the parent will just close workload.cork_fd, without writing
1489 		 * anything, i.e. read will return zero and we just exit()
1490 		 * here (See evlist__cancel_workload()).
1491 		 */
1492 		if (ret != 1) {
1493 			if (ret == -1)
1494 				perror("unable to read pipe");
1495 			exit(ret);
1496 		}
1497 
1498 		execvp(argv[0], (char **)argv);
1499 
1500 		if (exec_error) {
1501 			union sigval val;
1502 
1503 			val.sival_int = errno;
1504 			if (sigqueue(getppid(), SIGUSR1, val))
1505 				perror(argv[0]);
1506 		} else
1507 			perror(argv[0]);
1508 		exit(-1);
1509 	}
1510 
1511 	if (exec_error) {
1512 		struct sigaction act = {
1513 			.sa_flags     = SA_SIGINFO,
1514 			.sa_sigaction = exec_error,
1515 		};
1516 		sigaction(SIGUSR1, &act, NULL);
1517 	}
1518 
1519 	if (target__none(target)) {
1520 		if (evlist->core.threads == NULL) {
1521 			fprintf(stderr, "FATAL: evlist->threads need to be set at this point (%s:%d).\n",
1522 				__func__, __LINE__);
1523 			goto out_close_pipes;
1524 		}
1525 		perf_thread_map__set_pid(evlist->core.threads, 0, evlist->workload.pid);
1526 	}
1527 
1528 	close(child_ready_pipe[1]);
1529 	close(go_pipe[0]);
1530 	/*
1531 	 * wait for child to settle
1532 	 */
1533 	if (read(child_ready_pipe[0], &bf, 1) == -1) {
1534 		perror("unable to read pipe");
1535 		goto out_close_pipes;
1536 	}
1537 
1538 	fcntl(go_pipe[1], F_SETFD, FD_CLOEXEC);
1539 	evlist->workload.cork_fd = go_pipe[1];
1540 	close(child_ready_pipe[0]);
1541 	return 0;
1542 
1543 out_close_pipes:
1544 	close(go_pipe[0]);
1545 	close(go_pipe[1]);
1546 out_close_ready_pipe:
1547 	close(child_ready_pipe[0]);
1548 	close(child_ready_pipe[1]);
1549 	return -1;
1550 }
1551 
1552 int evlist__start_workload(struct evlist *evlist)
1553 {
1554 	if (evlist->workload.cork_fd >= 0) {
1555 		char bf = 0;
1556 		int ret;
1557 		/*
1558 		 * Remove the cork, let it rip!
1559 		 */
1560 		ret = write(evlist->workload.cork_fd, &bf, 1);
1561 		if (ret < 0)
1562 			perror("unable to write to pipe");
1563 
1564 		close(evlist->workload.cork_fd);
1565 		evlist->workload.cork_fd = -1;
1566 		return ret;
1567 	}
1568 
1569 	return 0;
1570 }
1571 
1572 void evlist__cancel_workload(struct evlist *evlist)
1573 {
1574 	int status;
1575 
1576 	if (evlist->workload.cork_fd >= 0) {
1577 		close(evlist->workload.cork_fd);
1578 		evlist->workload.cork_fd = -1;
1579 		waitpid(evlist->workload.pid, &status, WNOHANG);
1580 	}
1581 }
1582 
1583 int evlist__parse_sample(struct evlist *evlist, union perf_event *event, struct perf_sample *sample)
1584 {
1585 	struct evsel *evsel = evlist__event2evsel(evlist, event);
1586 	int ret;
1587 
1588 	if (!evsel)
1589 		return -EFAULT;
1590 	ret = evsel__parse_sample(evsel, event, sample);
1591 	if (ret)
1592 		return ret;
1593 	if (perf_guest && sample->id) {
1594 		struct perf_sample_id *sid = evlist__id2sid(evlist, sample->id);
1595 
1596 		if (sid) {
1597 			sample->machine_pid = sid->machine_pid;
1598 			sample->vcpu = sid->vcpu.cpu;
1599 		}
1600 	}
1601 	return 0;
1602 }
1603 
1604 int evlist__parse_sample_timestamp(struct evlist *evlist, union perf_event *event, u64 *timestamp)
1605 {
1606 	struct evsel *evsel = evlist__event2evsel(evlist, event);
1607 
1608 	if (!evsel)
1609 		return -EFAULT;
1610 	return evsel__parse_sample_timestamp(evsel, event, timestamp);
1611 }
1612 
1613 int evlist__strerror_open(struct evlist *evlist, int err, char *buf, size_t size)
1614 {
1615 	int printed, value;
1616 	char sbuf[STRERR_BUFSIZE], *emsg = str_error_r(err, sbuf, sizeof(sbuf));
1617 
1618 	switch (err) {
1619 	case EACCES:
1620 	case EPERM:
1621 		printed = scnprintf(buf, size,
1622 				    "Error:\t%s.\n"
1623 				    "Hint:\tCheck /proc/sys/kernel/perf_event_paranoid setting.", emsg);
1624 
1625 		value = perf_event_paranoid();
1626 
1627 		printed += scnprintf(buf + printed, size - printed, "\nHint:\t");
1628 
1629 		if (value >= 2) {
1630 			printed += scnprintf(buf + printed, size - printed,
1631 					     "For your workloads it needs to be <= 1\nHint:\t");
1632 		}
1633 		printed += scnprintf(buf + printed, size - printed,
1634 				     "For system wide tracing it needs to be set to -1.\n");
1635 
1636 		printed += scnprintf(buf + printed, size - printed,
1637 				    "Hint:\tTry: 'sudo sh -c \"echo -1 > /proc/sys/kernel/perf_event_paranoid\"'\n"
1638 				    "Hint:\tThe current value is %d.", value);
1639 		break;
1640 	case EINVAL: {
1641 		struct evsel *first = evlist__first(evlist);
1642 		int max_freq;
1643 
1644 		if (sysctl__read_int("kernel/perf_event_max_sample_rate", &max_freq) < 0)
1645 			goto out_default;
1646 
1647 		if (first->core.attr.sample_freq < (u64)max_freq)
1648 			goto out_default;
1649 
1650 		printed = scnprintf(buf, size,
1651 				    "Error:\t%s.\n"
1652 				    "Hint:\tCheck /proc/sys/kernel/perf_event_max_sample_rate.\n"
1653 				    "Hint:\tThe current value is %d and %" PRIu64 " is being requested.",
1654 				    emsg, max_freq, first->core.attr.sample_freq);
1655 		break;
1656 	}
1657 	default:
1658 out_default:
1659 		scnprintf(buf, size, "%s", emsg);
1660 		break;
1661 	}
1662 
1663 	return 0;
1664 }
1665 
1666 int evlist__strerror_mmap(struct evlist *evlist, int err, char *buf, size_t size)
1667 {
1668 	char sbuf[STRERR_BUFSIZE], *emsg = str_error_r(err, sbuf, sizeof(sbuf));
1669 	int pages_attempted = evlist->core.mmap_len / 1024, pages_max_per_user, printed = 0;
1670 
1671 	switch (err) {
1672 	case EPERM:
1673 		sysctl__read_int("kernel/perf_event_mlock_kb", &pages_max_per_user);
1674 		printed += scnprintf(buf + printed, size - printed,
1675 				     "Error:\t%s.\n"
1676 				     "Hint:\tCheck /proc/sys/kernel/perf_event_mlock_kb (%d kB) setting.\n"
1677 				     "Hint:\tTried using %zd kB.\n",
1678 				     emsg, pages_max_per_user, pages_attempted);
1679 
1680 		if (pages_attempted >= pages_max_per_user) {
1681 			printed += scnprintf(buf + printed, size - printed,
1682 					     "Hint:\tTry 'sudo sh -c \"echo %d > /proc/sys/kernel/perf_event_mlock_kb\"', or\n",
1683 					     pages_max_per_user + pages_attempted);
1684 		}
1685 
1686 		printed += scnprintf(buf + printed, size - printed,
1687 				     "Hint:\tTry using a smaller -m/--mmap-pages value.");
1688 		break;
1689 	default:
1690 		scnprintf(buf, size, "%s", emsg);
1691 		break;
1692 	}
1693 
1694 	return 0;
1695 }
1696 
1697 void evlist__to_front(struct evlist *evlist, struct evsel *move_evsel)
1698 {
1699 	struct evsel *evsel, *n;
1700 	LIST_HEAD(move);
1701 
1702 	if (move_evsel == evlist__first(evlist))
1703 		return;
1704 
1705 	evlist__for_each_entry_safe(evlist, n, evsel) {
1706 		if (evsel__leader(evsel) == evsel__leader(move_evsel))
1707 			list_move_tail(&evsel->core.node, &move);
1708 	}
1709 
1710 	list_splice(&move, &evlist->core.entries);
1711 }
1712 
1713 struct evsel *evlist__get_tracking_event(struct evlist *evlist)
1714 {
1715 	struct evsel *evsel;
1716 
1717 	evlist__for_each_entry(evlist, evsel) {
1718 		if (evsel->tracking)
1719 			return evsel;
1720 	}
1721 
1722 	return evlist__first(evlist);
1723 }
1724 
1725 void evlist__set_tracking_event(struct evlist *evlist, struct evsel *tracking_evsel)
1726 {
1727 	struct evsel *evsel;
1728 
1729 	if (tracking_evsel->tracking)
1730 		return;
1731 
1732 	evlist__for_each_entry(evlist, evsel) {
1733 		if (evsel != tracking_evsel)
1734 			evsel->tracking = false;
1735 	}
1736 
1737 	tracking_evsel->tracking = true;
1738 }
1739 
1740 struct evsel *evlist__findnew_tracking_event(struct evlist *evlist, bool system_wide)
1741 {
1742 	struct evsel *evsel;
1743 
1744 	evsel = evlist__get_tracking_event(evlist);
1745 	if (!evsel__is_dummy_event(evsel)) {
1746 		evsel = evlist__add_aux_dummy(evlist, system_wide);
1747 		if (!evsel)
1748 			return NULL;
1749 
1750 		evlist__set_tracking_event(evlist, evsel);
1751 	} else if (system_wide) {
1752 		perf_evlist__go_system_wide(&evlist->core, &evsel->core);
1753 	}
1754 
1755 	return evsel;
1756 }
1757 
1758 struct evsel *evlist__find_evsel_by_str(struct evlist *evlist, const char *str)
1759 {
1760 	struct evsel *evsel;
1761 
1762 	evlist__for_each_entry(evlist, evsel) {
1763 		if (!evsel->name)
1764 			continue;
1765 		if (evsel__name_is(evsel, str))
1766 			return evsel;
1767 	}
1768 
1769 	return NULL;
1770 }
1771 
1772 void evlist__toggle_bkw_mmap(struct evlist *evlist, enum bkw_mmap_state state)
1773 {
1774 	enum bkw_mmap_state old_state = evlist->bkw_mmap_state;
1775 	enum action {
1776 		NONE,
1777 		PAUSE,
1778 		RESUME,
1779 	} action = NONE;
1780 
1781 	if (!evlist->overwrite_mmap)
1782 		return;
1783 
1784 	switch (old_state) {
1785 	case BKW_MMAP_NOTREADY: {
1786 		if (state != BKW_MMAP_RUNNING)
1787 			goto state_err;
1788 		break;
1789 	}
1790 	case BKW_MMAP_RUNNING: {
1791 		if (state != BKW_MMAP_DATA_PENDING)
1792 			goto state_err;
1793 		action = PAUSE;
1794 		break;
1795 	}
1796 	case BKW_MMAP_DATA_PENDING: {
1797 		if (state != BKW_MMAP_EMPTY)
1798 			goto state_err;
1799 		break;
1800 	}
1801 	case BKW_MMAP_EMPTY: {
1802 		if (state != BKW_MMAP_RUNNING)
1803 			goto state_err;
1804 		action = RESUME;
1805 		break;
1806 	}
1807 	default:
1808 		WARN_ONCE(1, "Shouldn't get there\n");
1809 	}
1810 
1811 	evlist->bkw_mmap_state = state;
1812 
1813 	switch (action) {
1814 	case PAUSE:
1815 		evlist__pause(evlist);
1816 		break;
1817 	case RESUME:
1818 		evlist__resume(evlist);
1819 		break;
1820 	case NONE:
1821 	default:
1822 		break;
1823 	}
1824 
1825 state_err:
1826 	return;
1827 }
1828 
1829 bool evlist__exclude_kernel(struct evlist *evlist)
1830 {
1831 	struct evsel *evsel;
1832 
1833 	evlist__for_each_entry(evlist, evsel) {
1834 		if (!evsel->core.attr.exclude_kernel)
1835 			return false;
1836 	}
1837 
1838 	return true;
1839 }
1840 
1841 /*
1842  * Events in data file are not collect in groups, but we still want
1843  * the group display. Set the artificial group and set the leader's
1844  * forced_leader flag to notify the display code.
1845  */
1846 void evlist__force_leader(struct evlist *evlist)
1847 {
1848 	if (evlist__nr_groups(evlist) == 0) {
1849 		struct evsel *leader = evlist__first(evlist);
1850 
1851 		evlist__set_leader(evlist);
1852 		leader->forced_leader = true;
1853 	}
1854 }
1855 
1856 struct evsel *evlist__reset_weak_group(struct evlist *evsel_list, struct evsel *evsel, bool close)
1857 {
1858 	struct evsel *c2, *leader;
1859 	bool is_open = true;
1860 
1861 	leader = evsel__leader(evsel);
1862 
1863 	pr_debug("Weak group for %s/%d failed\n",
1864 			leader->name, leader->core.nr_members);
1865 
1866 	/*
1867 	 * for_each_group_member doesn't work here because it doesn't
1868 	 * include the first entry.
1869 	 */
1870 	evlist__for_each_entry(evsel_list, c2) {
1871 		if (c2 == evsel)
1872 			is_open = false;
1873 		if (evsel__has_leader(c2, leader)) {
1874 			if (is_open && close)
1875 				perf_evsel__close(&c2->core);
1876 			/*
1877 			 * We want to close all members of the group and reopen
1878 			 * them. Some events, like Intel topdown, require being
1879 			 * in a group and so keep these in the group.
1880 			 */
1881 			evsel__remove_from_group(c2, leader);
1882 
1883 			/*
1884 			 * Set this for all former members of the group
1885 			 * to indicate they get reopened.
1886 			 */
1887 			c2->reset_group = true;
1888 		}
1889 	}
1890 	/* Reset the leader count if all entries were removed. */
1891 	if (leader->core.nr_members == 1)
1892 		leader->core.nr_members = 0;
1893 	return leader;
1894 }
1895 
1896 static int evlist__parse_control_fifo(const char *str, int *ctl_fd, int *ctl_fd_ack, bool *ctl_fd_close)
1897 {
1898 	char *s, *p;
1899 	int ret = 0, fd;
1900 
1901 	if (strncmp(str, "fifo:", 5))
1902 		return -EINVAL;
1903 
1904 	str += 5;
1905 	if (!*str || *str == ',')
1906 		return -EINVAL;
1907 
1908 	s = strdup(str);
1909 	if (!s)
1910 		return -ENOMEM;
1911 
1912 	p = strchr(s, ',');
1913 	if (p)
1914 		*p = '\0';
1915 
1916 	/*
1917 	 * O_RDWR avoids POLLHUPs which is necessary to allow the other
1918 	 * end of a FIFO to be repeatedly opened and closed.
1919 	 */
1920 	fd = open(s, O_RDWR | O_NONBLOCK | O_CLOEXEC);
1921 	if (fd < 0) {
1922 		pr_err("Failed to open '%s'\n", s);
1923 		ret = -errno;
1924 		goto out_free;
1925 	}
1926 	*ctl_fd = fd;
1927 	*ctl_fd_close = true;
1928 
1929 	if (p && *++p) {
1930 		/* O_RDWR | O_NONBLOCK means the other end need not be open */
1931 		fd = open(p, O_RDWR | O_NONBLOCK | O_CLOEXEC);
1932 		if (fd < 0) {
1933 			pr_err("Failed to open '%s'\n", p);
1934 			ret = -errno;
1935 			goto out_free;
1936 		}
1937 		*ctl_fd_ack = fd;
1938 	}
1939 
1940 out_free:
1941 	free(s);
1942 	return ret;
1943 }
1944 
1945 int evlist__parse_control(const char *str, int *ctl_fd, int *ctl_fd_ack, bool *ctl_fd_close)
1946 {
1947 	char *comma = NULL, *endptr = NULL;
1948 
1949 	*ctl_fd_close = false;
1950 
1951 	if (strncmp(str, "fd:", 3))
1952 		return evlist__parse_control_fifo(str, ctl_fd, ctl_fd_ack, ctl_fd_close);
1953 
1954 	*ctl_fd = strtoul(&str[3], &endptr, 0);
1955 	if (endptr == &str[3])
1956 		return -EINVAL;
1957 
1958 	comma = strchr(str, ',');
1959 	if (comma) {
1960 		if (endptr != comma)
1961 			return -EINVAL;
1962 
1963 		*ctl_fd_ack = strtoul(comma + 1, &endptr, 0);
1964 		if (endptr == comma + 1 || *endptr != '\0')
1965 			return -EINVAL;
1966 	}
1967 
1968 	return 0;
1969 }
1970 
1971 void evlist__close_control(int ctl_fd, int ctl_fd_ack, bool *ctl_fd_close)
1972 {
1973 	if (*ctl_fd_close) {
1974 		*ctl_fd_close = false;
1975 		close(ctl_fd);
1976 		if (ctl_fd_ack >= 0)
1977 			close(ctl_fd_ack);
1978 	}
1979 }
1980 
1981 int evlist__initialize_ctlfd(struct evlist *evlist, int fd, int ack)
1982 {
1983 	if (fd == -1) {
1984 		pr_debug("Control descriptor is not initialized\n");
1985 		return 0;
1986 	}
1987 
1988 	evlist->ctl_fd.pos = perf_evlist__add_pollfd(&evlist->core, fd, NULL, POLLIN,
1989 						     fdarray_flag__nonfilterable |
1990 						     fdarray_flag__non_perf_event);
1991 	if (evlist->ctl_fd.pos < 0) {
1992 		evlist->ctl_fd.pos = -1;
1993 		pr_err("Failed to add ctl fd entry: %m\n");
1994 		return -1;
1995 	}
1996 
1997 	evlist->ctl_fd.fd = fd;
1998 	evlist->ctl_fd.ack = ack;
1999 
2000 	return 0;
2001 }
2002 
2003 bool evlist__ctlfd_initialized(struct evlist *evlist)
2004 {
2005 	return evlist->ctl_fd.pos >= 0;
2006 }
2007 
2008 int evlist__finalize_ctlfd(struct evlist *evlist)
2009 {
2010 	struct pollfd *entries = evlist->core.pollfd.entries;
2011 
2012 	if (!evlist__ctlfd_initialized(evlist))
2013 		return 0;
2014 
2015 	entries[evlist->ctl_fd.pos].fd = -1;
2016 	entries[evlist->ctl_fd.pos].events = 0;
2017 	entries[evlist->ctl_fd.pos].revents = 0;
2018 
2019 	evlist->ctl_fd.pos = -1;
2020 	evlist->ctl_fd.ack = -1;
2021 	evlist->ctl_fd.fd = -1;
2022 
2023 	return 0;
2024 }
2025 
2026 static int evlist__ctlfd_recv(struct evlist *evlist, enum evlist_ctl_cmd *cmd,
2027 			      char *cmd_data, size_t data_size)
2028 {
2029 	int err;
2030 	char c;
2031 	size_t bytes_read = 0;
2032 
2033 	*cmd = EVLIST_CTL_CMD_UNSUPPORTED;
2034 	memset(cmd_data, 0, data_size);
2035 	data_size--;
2036 
2037 	do {
2038 		err = read(evlist->ctl_fd.fd, &c, 1);
2039 		if (err > 0) {
2040 			if (c == '\n' || c == '\0')
2041 				break;
2042 			cmd_data[bytes_read++] = c;
2043 			if (bytes_read == data_size)
2044 				break;
2045 			continue;
2046 		} else if (err == -1) {
2047 			if (errno == EINTR)
2048 				continue;
2049 			if (errno == EAGAIN || errno == EWOULDBLOCK)
2050 				err = 0;
2051 			else
2052 				pr_err("Failed to read from ctlfd %d: %m\n", evlist->ctl_fd.fd);
2053 		}
2054 		break;
2055 	} while (1);
2056 
2057 	pr_debug("Message from ctl_fd: \"%s%s\"\n", cmd_data,
2058 		 bytes_read == data_size ? "" : c == '\n' ? "\\n" : "\\0");
2059 
2060 	if (bytes_read > 0) {
2061 		if (!strncmp(cmd_data, EVLIST_CTL_CMD_ENABLE_TAG,
2062 			     (sizeof(EVLIST_CTL_CMD_ENABLE_TAG)-1))) {
2063 			*cmd = EVLIST_CTL_CMD_ENABLE;
2064 		} else if (!strncmp(cmd_data, EVLIST_CTL_CMD_DISABLE_TAG,
2065 				    (sizeof(EVLIST_CTL_CMD_DISABLE_TAG)-1))) {
2066 			*cmd = EVLIST_CTL_CMD_DISABLE;
2067 		} else if (!strncmp(cmd_data, EVLIST_CTL_CMD_SNAPSHOT_TAG,
2068 				    (sizeof(EVLIST_CTL_CMD_SNAPSHOT_TAG)-1))) {
2069 			*cmd = EVLIST_CTL_CMD_SNAPSHOT;
2070 			pr_debug("is snapshot\n");
2071 		} else if (!strncmp(cmd_data, EVLIST_CTL_CMD_EVLIST_TAG,
2072 				    (sizeof(EVLIST_CTL_CMD_EVLIST_TAG)-1))) {
2073 			*cmd = EVLIST_CTL_CMD_EVLIST;
2074 		} else if (!strncmp(cmd_data, EVLIST_CTL_CMD_STOP_TAG,
2075 				    (sizeof(EVLIST_CTL_CMD_STOP_TAG)-1))) {
2076 			*cmd = EVLIST_CTL_CMD_STOP;
2077 		} else if (!strncmp(cmd_data, EVLIST_CTL_CMD_PING_TAG,
2078 				    (sizeof(EVLIST_CTL_CMD_PING_TAG)-1))) {
2079 			*cmd = EVLIST_CTL_CMD_PING;
2080 		}
2081 	}
2082 
2083 	return bytes_read ? (int)bytes_read : err;
2084 }
2085 
2086 int evlist__ctlfd_ack(struct evlist *evlist)
2087 {
2088 	int err;
2089 
2090 	if (evlist->ctl_fd.ack == -1)
2091 		return 0;
2092 
2093 	err = write(evlist->ctl_fd.ack, EVLIST_CTL_CMD_ACK_TAG,
2094 		    sizeof(EVLIST_CTL_CMD_ACK_TAG));
2095 	if (err == -1)
2096 		pr_err("failed to write to ctl_ack_fd %d: %m\n", evlist->ctl_fd.ack);
2097 
2098 	return err;
2099 }
2100 
2101 static int get_cmd_arg(char *cmd_data, size_t cmd_size, char **arg)
2102 {
2103 	char *data = cmd_data + cmd_size;
2104 
2105 	/* no argument */
2106 	if (!*data)
2107 		return 0;
2108 
2109 	/* there's argument */
2110 	if (*data == ' ') {
2111 		*arg = data + 1;
2112 		return 1;
2113 	}
2114 
2115 	/* malformed */
2116 	return -1;
2117 }
2118 
2119 static int evlist__ctlfd_enable(struct evlist *evlist, char *cmd_data, bool enable)
2120 {
2121 	struct evsel *evsel;
2122 	char *name;
2123 	int err;
2124 
2125 	err = get_cmd_arg(cmd_data,
2126 			  enable ? sizeof(EVLIST_CTL_CMD_ENABLE_TAG) - 1 :
2127 				   sizeof(EVLIST_CTL_CMD_DISABLE_TAG) - 1,
2128 			  &name);
2129 	if (err < 0) {
2130 		pr_info("failed: wrong command\n");
2131 		return -1;
2132 	}
2133 
2134 	if (err) {
2135 		evsel = evlist__find_evsel_by_str(evlist, name);
2136 		if (evsel) {
2137 			if (enable)
2138 				evlist__enable_evsel(evlist, name);
2139 			else
2140 				evlist__disable_evsel(evlist, name);
2141 			pr_info("Event %s %s\n", evsel->name,
2142 				enable ? "enabled" : "disabled");
2143 		} else {
2144 			pr_info("failed: can't find '%s' event\n", name);
2145 		}
2146 	} else {
2147 		if (enable) {
2148 			evlist__enable(evlist);
2149 			pr_info(EVLIST_ENABLED_MSG);
2150 		} else {
2151 			evlist__disable(evlist);
2152 			pr_info(EVLIST_DISABLED_MSG);
2153 		}
2154 	}
2155 
2156 	return 0;
2157 }
2158 
2159 static int evlist__ctlfd_list(struct evlist *evlist, char *cmd_data)
2160 {
2161 	struct perf_attr_details details = { .verbose = false, };
2162 	struct evsel *evsel;
2163 	char *arg;
2164 	int err;
2165 
2166 	err = get_cmd_arg(cmd_data,
2167 			  sizeof(EVLIST_CTL_CMD_EVLIST_TAG) - 1,
2168 			  &arg);
2169 	if (err < 0) {
2170 		pr_info("failed: wrong command\n");
2171 		return -1;
2172 	}
2173 
2174 	if (err) {
2175 		if (!strcmp(arg, "-v")) {
2176 			details.verbose = true;
2177 		} else if (!strcmp(arg, "-g")) {
2178 			details.event_group = true;
2179 		} else if (!strcmp(arg, "-F")) {
2180 			details.freq = true;
2181 		} else {
2182 			pr_info("failed: wrong command\n");
2183 			return -1;
2184 		}
2185 	}
2186 
2187 	evlist__for_each_entry(evlist, evsel)
2188 		evsel__fprintf(evsel, &details, stderr);
2189 
2190 	return 0;
2191 }
2192 
2193 int evlist__ctlfd_process(struct evlist *evlist, enum evlist_ctl_cmd *cmd)
2194 {
2195 	int err = 0;
2196 	char cmd_data[EVLIST_CTL_CMD_MAX_LEN];
2197 	int ctlfd_pos = evlist->ctl_fd.pos;
2198 	struct pollfd *entries = evlist->core.pollfd.entries;
2199 
2200 	if (!evlist__ctlfd_initialized(evlist) || !entries[ctlfd_pos].revents)
2201 		return 0;
2202 
2203 	if (entries[ctlfd_pos].revents & POLLIN) {
2204 		err = evlist__ctlfd_recv(evlist, cmd, cmd_data,
2205 					 EVLIST_CTL_CMD_MAX_LEN);
2206 		if (err > 0) {
2207 			switch (*cmd) {
2208 			case EVLIST_CTL_CMD_ENABLE:
2209 			case EVLIST_CTL_CMD_DISABLE:
2210 				err = evlist__ctlfd_enable(evlist, cmd_data,
2211 							   *cmd == EVLIST_CTL_CMD_ENABLE);
2212 				break;
2213 			case EVLIST_CTL_CMD_EVLIST:
2214 				err = evlist__ctlfd_list(evlist, cmd_data);
2215 				break;
2216 			case EVLIST_CTL_CMD_SNAPSHOT:
2217 			case EVLIST_CTL_CMD_STOP:
2218 			case EVLIST_CTL_CMD_PING:
2219 				break;
2220 			case EVLIST_CTL_CMD_ACK:
2221 			case EVLIST_CTL_CMD_UNSUPPORTED:
2222 			default:
2223 				pr_debug("ctlfd: unsupported %d\n", *cmd);
2224 				break;
2225 			}
2226 			if (!(*cmd == EVLIST_CTL_CMD_ACK || *cmd == EVLIST_CTL_CMD_UNSUPPORTED ||
2227 			      *cmd == EVLIST_CTL_CMD_SNAPSHOT))
2228 				evlist__ctlfd_ack(evlist);
2229 		}
2230 	}
2231 
2232 	if (entries[ctlfd_pos].revents & (POLLHUP | POLLERR))
2233 		evlist__finalize_ctlfd(evlist);
2234 	else
2235 		entries[ctlfd_pos].revents = 0;
2236 
2237 	return err;
2238 }
2239 
2240 /**
2241  * struct event_enable_time - perf record -D/--delay single time range.
2242  * @start: start of time range to enable events in milliseconds
2243  * @end: end of time range to enable events in milliseconds
2244  *
2245  * N.B. this structure is also accessed as an array of int.
2246  */
2247 struct event_enable_time {
2248 	int	start;
2249 	int	end;
2250 };
2251 
2252 static int parse_event_enable_time(const char *str, struct event_enable_time *range, bool first)
2253 {
2254 	const char *fmt = first ? "%u - %u %n" : " , %u - %u %n";
2255 	int ret, start, end, n;
2256 
2257 	ret = sscanf(str, fmt, &start, &end, &n);
2258 	if (ret != 2 || end <= start)
2259 		return -EINVAL;
2260 	if (range) {
2261 		range->start = start;
2262 		range->end = end;
2263 	}
2264 	return n;
2265 }
2266 
2267 static ssize_t parse_event_enable_times(const char *str, struct event_enable_time *range)
2268 {
2269 	int incr = !!range;
2270 	bool first = true;
2271 	ssize_t ret, cnt;
2272 
2273 	for (cnt = 0; *str; cnt++) {
2274 		ret = parse_event_enable_time(str, range, first);
2275 		if (ret < 0)
2276 			return ret;
2277 		/* Check no overlap */
2278 		if (!first && range && range->start <= range[-1].end)
2279 			return -EINVAL;
2280 		str += ret;
2281 		range += incr;
2282 		first = false;
2283 	}
2284 	return cnt;
2285 }
2286 
2287 /**
2288  * struct event_enable_timer - control structure for perf record -D/--delay.
2289  * @evlist: event list
2290  * @times: time ranges that events are enabled (N.B. this is also accessed as an
2291  *         array of int)
2292  * @times_cnt: number of time ranges
2293  * @timerfd: timer file descriptor
2294  * @pollfd_pos: position in @evlist array of file descriptors to poll (fdarray)
2295  * @times_step: current position in (int *)@times)[],
2296  *              refer event_enable_timer__process()
2297  *
2298  * Note, this structure is only used when there are time ranges, not when there
2299  * is only an initial delay.
2300  */
2301 struct event_enable_timer {
2302 	struct evlist *evlist;
2303 	struct event_enable_time *times;
2304 	size_t	times_cnt;
2305 	int	timerfd;
2306 	int	pollfd_pos;
2307 	size_t	times_step;
2308 };
2309 
2310 static int str_to_delay(const char *str)
2311 {
2312 	char *endptr;
2313 	long d;
2314 
2315 	d = strtol(str, &endptr, 10);
2316 	if (*endptr || d > INT_MAX || d < -1)
2317 		return 0;
2318 	return d;
2319 }
2320 
2321 int evlist__parse_event_enable_time(struct evlist *evlist, struct record_opts *opts,
2322 				    const char *str, int unset)
2323 {
2324 	enum fdarray_flags flags = fdarray_flag__nonfilterable | fdarray_flag__non_perf_event;
2325 	struct event_enable_timer *eet;
2326 	ssize_t times_cnt;
2327 	ssize_t ret;
2328 	int err;
2329 
2330 	if (unset)
2331 		return 0;
2332 
2333 	opts->target.initial_delay = str_to_delay(str);
2334 	if (opts->target.initial_delay)
2335 		return 0;
2336 
2337 	ret = parse_event_enable_times(str, NULL);
2338 	if (ret < 0)
2339 		return ret;
2340 
2341 	times_cnt = ret;
2342 	if (times_cnt == 0)
2343 		return -EINVAL;
2344 
2345 	eet = zalloc(sizeof(*eet));
2346 	if (!eet)
2347 		return -ENOMEM;
2348 
2349 	eet->times = calloc(times_cnt, sizeof(*eet->times));
2350 	if (!eet->times) {
2351 		err = -ENOMEM;
2352 		goto free_eet;
2353 	}
2354 
2355 	if (parse_event_enable_times(str, eet->times) != times_cnt) {
2356 		err = -EINVAL;
2357 		goto free_eet_times;
2358 	}
2359 
2360 	eet->times_cnt = times_cnt;
2361 
2362 	eet->timerfd = timerfd_create(CLOCK_MONOTONIC, TFD_CLOEXEC);
2363 	if (eet->timerfd == -1) {
2364 		err = -errno;
2365 		pr_err("timerfd_create failed: %s\n", strerror(errno));
2366 		goto free_eet_times;
2367 	}
2368 
2369 	eet->pollfd_pos = perf_evlist__add_pollfd(&evlist->core, eet->timerfd, NULL, POLLIN, flags);
2370 	if (eet->pollfd_pos < 0) {
2371 		err = eet->pollfd_pos;
2372 		goto close_timerfd;
2373 	}
2374 
2375 	eet->evlist = evlist;
2376 	evlist->eet = eet;
2377 	opts->target.initial_delay = eet->times[0].start;
2378 
2379 	return 0;
2380 
2381 close_timerfd:
2382 	close(eet->timerfd);
2383 free_eet_times:
2384 	zfree(&eet->times);
2385 free_eet:
2386 	free(eet);
2387 	return err;
2388 }
2389 
2390 static int event_enable_timer__set_timer(struct event_enable_timer *eet, int ms)
2391 {
2392 	struct itimerspec its = {
2393 		.it_value.tv_sec = ms / MSEC_PER_SEC,
2394 		.it_value.tv_nsec = (ms % MSEC_PER_SEC) * NSEC_PER_MSEC,
2395 	};
2396 	int err = 0;
2397 
2398 	if (timerfd_settime(eet->timerfd, 0, &its, NULL) < 0) {
2399 		err = -errno;
2400 		pr_err("timerfd_settime failed: %s\n", strerror(errno));
2401 	}
2402 	return err;
2403 }
2404 
2405 int event_enable_timer__start(struct event_enable_timer *eet)
2406 {
2407 	int ms;
2408 
2409 	if (!eet)
2410 		return 0;
2411 
2412 	ms = eet->times[0].end - eet->times[0].start;
2413 	eet->times_step = 1;
2414 
2415 	return event_enable_timer__set_timer(eet, ms);
2416 }
2417 
2418 int event_enable_timer__process(struct event_enable_timer *eet)
2419 {
2420 	struct pollfd *entries;
2421 	short revents;
2422 
2423 	if (!eet)
2424 		return 0;
2425 
2426 	entries = eet->evlist->core.pollfd.entries;
2427 	revents = entries[eet->pollfd_pos].revents;
2428 	entries[eet->pollfd_pos].revents = 0;
2429 
2430 	if (revents & POLLIN) {
2431 		size_t step = eet->times_step;
2432 		size_t pos = step / 2;
2433 
2434 		if (step & 1) {
2435 			evlist__disable_non_dummy(eet->evlist);
2436 			pr_info(EVLIST_DISABLED_MSG);
2437 			if (pos >= eet->times_cnt - 1) {
2438 				/* Disarm timer */
2439 				event_enable_timer__set_timer(eet, 0);
2440 				return 1; /* Stop */
2441 			}
2442 		} else {
2443 			evlist__enable_non_dummy(eet->evlist);
2444 			pr_info(EVLIST_ENABLED_MSG);
2445 		}
2446 
2447 		step += 1;
2448 		pos = step / 2;
2449 
2450 		if (pos < eet->times_cnt) {
2451 			int *times = (int *)eet->times; /* Accessing 'times' as array of int */
2452 			int ms = times[step] - times[step - 1];
2453 
2454 			eet->times_step = step;
2455 			return event_enable_timer__set_timer(eet, ms);
2456 		}
2457 	}
2458 
2459 	return 0;
2460 }
2461 
2462 void event_enable_timer__exit(struct event_enable_timer **ep)
2463 {
2464 	if (!ep || !*ep)
2465 		return;
2466 	zfree(&(*ep)->times);
2467 	zfree(ep);
2468 }
2469 
2470 struct evsel *evlist__find_evsel(struct evlist *evlist, int idx)
2471 {
2472 	struct evsel *evsel;
2473 
2474 	evlist__for_each_entry(evlist, evsel) {
2475 		if (evsel->core.idx == idx)
2476 			return evsel;
2477 	}
2478 	return NULL;
2479 }
2480 
2481 void evlist__format_evsels(struct evlist *evlist, struct strbuf *sb, size_t max_length)
2482 {
2483 	struct evsel *evsel, *leader = NULL;
2484 	bool first = true;
2485 
2486 	evlist__for_each_entry(evlist, evsel) {
2487 		struct evsel *new_leader = evsel__leader(evsel);
2488 
2489 		if (evsel__is_dummy_event(evsel))
2490 			continue;
2491 
2492 		if (leader != new_leader && leader && leader->core.nr_members > 1)
2493 			strbuf_addch(sb, '}');
2494 
2495 		if (!first)
2496 			strbuf_addch(sb, ',');
2497 
2498 		if (sb->len > max_length) {
2499 			strbuf_addstr(sb, "...");
2500 			return;
2501 		}
2502 		if (leader != new_leader && new_leader->core.nr_members > 1)
2503 			strbuf_addch(sb, '{');
2504 
2505 		strbuf_addstr(sb, evsel__name(evsel));
2506 		first = false;
2507 		leader = new_leader;
2508 	}
2509 	if (leader && leader->core.nr_members > 1)
2510 		strbuf_addch(sb, '}');
2511 }
2512 
2513 void evlist__check_mem_load_aux(struct evlist *evlist)
2514 {
2515 	struct evsel *leader, *evsel, *pos;
2516 
2517 	/*
2518 	 * For some platforms, the 'mem-loads' event is required to use
2519 	 * together with 'mem-loads-aux' within a group and 'mem-loads-aux'
2520 	 * must be the group leader. Now we disable this group before reporting
2521 	 * because 'mem-loads-aux' is just an auxiliary event. It doesn't carry
2522 	 * any valid memory load information.
2523 	 */
2524 	evlist__for_each_entry(evlist, evsel) {
2525 		leader = evsel__leader(evsel);
2526 		if (leader == evsel)
2527 			continue;
2528 
2529 		if (leader->name && strstr(leader->name, "mem-loads-aux")) {
2530 			for_each_group_evsel(pos, leader) {
2531 				evsel__set_leader(pos, pos);
2532 				pos->core.nr_members = 0;
2533 			}
2534 		}
2535 	}
2536 }
2537 
2538 /**
2539  * evlist__warn_user_requested_cpus() - Check each evsel against requested CPUs
2540  *     and warn if the user CPU list is inapplicable for the event's PMU's
2541  *     CPUs. Not core PMUs list a CPU in sysfs, but this may be overwritten by a
2542  *     user requested CPU and so any online CPU is applicable. Core PMUs handle
2543  *     events on the CPUs in their list and otherwise the event isn't supported.
2544  * @evlist: The list of events being checked.
2545  * @cpu_list: The user provided list of CPUs.
2546  */
2547 void evlist__warn_user_requested_cpus(struct evlist *evlist, const char *cpu_list)
2548 {
2549 	struct perf_cpu_map *user_requested_cpus;
2550 	struct evsel *pos;
2551 
2552 	if (!cpu_list)
2553 		return;
2554 
2555 	user_requested_cpus = perf_cpu_map__new(cpu_list);
2556 	if (!user_requested_cpus)
2557 		return;
2558 
2559 	evlist__for_each_entry(evlist, pos) {
2560 		evsel__warn_user_requested_cpus(pos, user_requested_cpus);
2561 	}
2562 	perf_cpu_map__put(user_requested_cpus);
2563 }
2564 
2565 /* Should uniquify be disabled for the evlist? */
2566 static bool evlist__disable_uniquify(const struct evlist *evlist)
2567 {
2568 	struct evsel *counter;
2569 	struct perf_pmu *last_pmu = NULL;
2570 	bool first = true;
2571 
2572 	evlist__for_each_entry(evlist, counter) {
2573 		/* If PMUs vary then uniquify can be useful. */
2574 		if (!first && counter->pmu != last_pmu)
2575 			return false;
2576 		first = false;
2577 		if (counter->pmu) {
2578 			/* Allow uniquify for uncore PMUs. */
2579 			if (!counter->pmu->is_core)
2580 				return false;
2581 			/* Keep hybrid event names uniquified for clarity. */
2582 			if (perf_pmus__num_core_pmus() > 1)
2583 				return false;
2584 		}
2585 		last_pmu = counter->pmu;
2586 	}
2587 	return true;
2588 }
2589 
2590 static bool evlist__set_needs_uniquify(struct evlist *evlist, const struct perf_stat_config *config)
2591 {
2592 	struct evsel *counter;
2593 	bool needs_uniquify = false;
2594 
2595 	if (evlist__disable_uniquify(evlist)) {
2596 		evlist__for_each_entry(evlist, counter)
2597 			counter->uniquified_name = true;
2598 		return false;
2599 	}
2600 
2601 	evlist__for_each_entry(evlist, counter) {
2602 		if (evsel__set_needs_uniquify(counter, config))
2603 			needs_uniquify = true;
2604 	}
2605 	return needs_uniquify;
2606 }
2607 
2608 void evlist__uniquify_evsel_names(struct evlist *evlist, const struct perf_stat_config *config)
2609 {
2610 	if (evlist__set_needs_uniquify(evlist, config)) {
2611 		struct evsel *pos;
2612 
2613 		evlist__for_each_entry(evlist, pos)
2614 			evsel__uniquify_counter(pos);
2615 	}
2616 }
2617 
2618 bool evlist__has_bpf_output(struct evlist *evlist)
2619 {
2620 	struct evsel *evsel;
2621 
2622 	evlist__for_each_entry(evlist, evsel) {
2623 		if (evsel__is_bpf_output(evsel))
2624 			return true;
2625 	}
2626 
2627 	return false;
2628 }
2629 
2630 bool evlist__needs_bpf_sb_event(struct evlist *evlist)
2631 {
2632 	struct evsel *evsel;
2633 
2634 	evlist__for_each_entry(evlist, evsel) {
2635 		if (evsel__is_dummy_event(evsel))
2636 			continue;
2637 		if (!evsel->core.attr.exclude_kernel)
2638 			return true;
2639 	}
2640 
2641 	return false;
2642 }
2643