perf thread_map: Enumerate all threads from /proc
[linux-2.6-microblaze.git] / tools / perf / util / evlist.c
1 /*
2  * Copyright (C) 2011, Red Hat Inc, Arnaldo Carvalho de Melo <acme@redhat.com>
3  *
4  * Parts came from builtin-{top,stat,record}.c, see those files for further
5  * copyright notes.
6  *
7  * Released under the GPL v2. (and only v2, not any later version)
8  */
9 #include "util.h"
10 #include <api/fs/fs.h>
11 #include <errno.h>
12 #include <inttypes.h>
13 #include <poll.h>
14 #include "cpumap.h"
15 #include "thread_map.h"
16 #include "target.h"
17 #include "evlist.h"
18 #include "evsel.h"
19 #include "debug.h"
20 #include "units.h"
21 #include "asm/bug.h"
22 #include <signal.h>
23 #include <unistd.h>
24
25 #include "parse-events.h"
26 #include <subcmd/parse-options.h>
27
28 #include <sys/ioctl.h>
29 #include <sys/mman.h>
30
31 #include <linux/bitops.h>
32 #include <linux/hash.h>
33 #include <linux/log2.h>
34 #include <linux/err.h>
35
36 #define FD(e, x, y) (*(int *)xyarray__entry(e->fd, x, y))
37 #define SID(e, x, y) xyarray__entry(e->sample_id, x, y)
38
39 void perf_evlist__init(struct perf_evlist *evlist, struct cpu_map *cpus,
40                        struct thread_map *threads)
41 {
42         int i;
43
44         for (i = 0; i < PERF_EVLIST__HLIST_SIZE; ++i)
45                 INIT_HLIST_HEAD(&evlist->heads[i]);
46         INIT_LIST_HEAD(&evlist->entries);
47         perf_evlist__set_maps(evlist, cpus, threads);
48         fdarray__init(&evlist->pollfd, 64);
49         evlist->workload.pid = -1;
50         evlist->bkw_mmap_state = BKW_MMAP_NOTREADY;
51 }
52
53 struct perf_evlist *perf_evlist__new(void)
54 {
55         struct perf_evlist *evlist = zalloc(sizeof(*evlist));
56
57         if (evlist != NULL)
58                 perf_evlist__init(evlist, NULL, NULL);
59
60         return evlist;
61 }
62
63 struct perf_evlist *perf_evlist__new_default(void)
64 {
65         struct perf_evlist *evlist = perf_evlist__new();
66
67         if (evlist && perf_evlist__add_default(evlist)) {
68                 perf_evlist__delete(evlist);
69                 evlist = NULL;
70         }
71
72         return evlist;
73 }
74
75 struct perf_evlist *perf_evlist__new_dummy(void)
76 {
77         struct perf_evlist *evlist = perf_evlist__new();
78
79         if (evlist && perf_evlist__add_dummy(evlist)) {
80                 perf_evlist__delete(evlist);
81                 evlist = NULL;
82         }
83
84         return evlist;
85 }
86
87 /**
88  * perf_evlist__set_id_pos - set the positions of event ids.
89  * @evlist: selected event list
90  *
91  * Events with compatible sample types all have the same id_pos
92  * and is_pos.  For convenience, put a copy on evlist.
93  */
94 void perf_evlist__set_id_pos(struct perf_evlist *evlist)
95 {
96         struct perf_evsel *first = perf_evlist__first(evlist);
97
98         evlist->id_pos = first->id_pos;
99         evlist->is_pos = first->is_pos;
100 }
101
102 static void perf_evlist__update_id_pos(struct perf_evlist *evlist)
103 {
104         struct perf_evsel *evsel;
105
106         evlist__for_each_entry(evlist, evsel)
107                 perf_evsel__calc_id_pos(evsel);
108
109         perf_evlist__set_id_pos(evlist);
110 }
111
112 static void perf_evlist__purge(struct perf_evlist *evlist)
113 {
114         struct perf_evsel *pos, *n;
115
116         evlist__for_each_entry_safe(evlist, n, pos) {
117                 list_del_init(&pos->node);
118                 pos->evlist = NULL;
119                 perf_evsel__delete(pos);
120         }
121
122         evlist->nr_entries = 0;
123 }
124
125 void perf_evlist__exit(struct perf_evlist *evlist)
126 {
127         zfree(&evlist->mmap);
128         zfree(&evlist->overwrite_mmap);
129         fdarray__exit(&evlist->pollfd);
130 }
131
132 void perf_evlist__delete(struct perf_evlist *evlist)
133 {
134         if (evlist == NULL)
135                 return;
136
137         perf_evlist__munmap(evlist);
138         perf_evlist__close(evlist);
139         cpu_map__put(evlist->cpus);
140         thread_map__put(evlist->threads);
141         evlist->cpus = NULL;
142         evlist->threads = NULL;
143         perf_evlist__purge(evlist);
144         perf_evlist__exit(evlist);
145         free(evlist);
146 }
147
148 static void __perf_evlist__propagate_maps(struct perf_evlist *evlist,
149                                           struct perf_evsel *evsel)
150 {
151         /*
152          * We already have cpus for evsel (via PMU sysfs) so
153          * keep it, if there's no target cpu list defined.
154          */
155         if (!evsel->own_cpus || evlist->has_user_cpus) {
156                 cpu_map__put(evsel->cpus);
157                 evsel->cpus = cpu_map__get(evlist->cpus);
158         } else if (evsel->cpus != evsel->own_cpus) {
159                 cpu_map__put(evsel->cpus);
160                 evsel->cpus = cpu_map__get(evsel->own_cpus);
161         }
162
163         thread_map__put(evsel->threads);
164         evsel->threads = thread_map__get(evlist->threads);
165 }
166
167 static void perf_evlist__propagate_maps(struct perf_evlist *evlist)
168 {
169         struct perf_evsel *evsel;
170
171         evlist__for_each_entry(evlist, evsel)
172                 __perf_evlist__propagate_maps(evlist, evsel);
173 }
174
175 void perf_evlist__add(struct perf_evlist *evlist, struct perf_evsel *entry)
176 {
177         entry->evlist = evlist;
178         list_add_tail(&entry->node, &evlist->entries);
179         entry->idx = evlist->nr_entries;
180         entry->tracking = !entry->idx;
181
182         if (!evlist->nr_entries++)
183                 perf_evlist__set_id_pos(evlist);
184
185         __perf_evlist__propagate_maps(evlist, entry);
186 }
187
188 void perf_evlist__remove(struct perf_evlist *evlist, struct perf_evsel *evsel)
189 {
190         evsel->evlist = NULL;
191         list_del_init(&evsel->node);
192         evlist->nr_entries -= 1;
193 }
194
195 void perf_evlist__splice_list_tail(struct perf_evlist *evlist,
196                                    struct list_head *list)
197 {
198         struct perf_evsel *evsel, *temp;
199
200         __evlist__for_each_entry_safe(list, temp, evsel) {
201                 list_del_init(&evsel->node);
202                 perf_evlist__add(evlist, evsel);
203         }
204 }
205
206 void __perf_evlist__set_leader(struct list_head *list)
207 {
208         struct perf_evsel *evsel, *leader;
209
210         leader = list_entry(list->next, struct perf_evsel, node);
211         evsel = list_entry(list->prev, struct perf_evsel, node);
212
213         leader->nr_members = evsel->idx - leader->idx + 1;
214
215         __evlist__for_each_entry(list, evsel) {
216                 evsel->leader = leader;
217         }
218 }
219
220 void perf_evlist__set_leader(struct perf_evlist *evlist)
221 {
222         if (evlist->nr_entries) {
223                 evlist->nr_groups = evlist->nr_entries > 1 ? 1 : 0;
224                 __perf_evlist__set_leader(&evlist->entries);
225         }
226 }
227
228 void perf_event_attr__set_max_precise_ip(struct perf_event_attr *attr)
229 {
230         attr->precise_ip = 3;
231
232         while (attr->precise_ip != 0) {
233                 int fd = sys_perf_event_open(attr, 0, -1, -1, 0);
234                 if (fd != -1) {
235                         close(fd);
236                         break;
237                 }
238                 --attr->precise_ip;
239         }
240 }
241
242 int __perf_evlist__add_default(struct perf_evlist *evlist, bool precise)
243 {
244         struct perf_evsel *evsel = perf_evsel__new_cycles(precise);
245
246         if (evsel == NULL)
247                 return -ENOMEM;
248
249         perf_evlist__add(evlist, evsel);
250         return 0;
251 }
252
253 int perf_evlist__add_dummy(struct perf_evlist *evlist)
254 {
255         struct perf_event_attr attr = {
256                 .type   = PERF_TYPE_SOFTWARE,
257                 .config = PERF_COUNT_SW_DUMMY,
258                 .size   = sizeof(attr), /* to capture ABI version */
259         };
260         struct perf_evsel *evsel = perf_evsel__new_idx(&attr, evlist->nr_entries);
261
262         if (evsel == NULL)
263                 return -ENOMEM;
264
265         perf_evlist__add(evlist, evsel);
266         return 0;
267 }
268
269 static int perf_evlist__add_attrs(struct perf_evlist *evlist,
270                                   struct perf_event_attr *attrs, size_t nr_attrs)
271 {
272         struct perf_evsel *evsel, *n;
273         LIST_HEAD(head);
274         size_t i;
275
276         for (i = 0; i < nr_attrs; i++) {
277                 evsel = perf_evsel__new_idx(attrs + i, evlist->nr_entries + i);
278                 if (evsel == NULL)
279                         goto out_delete_partial_list;
280                 list_add_tail(&evsel->node, &head);
281         }
282
283         perf_evlist__splice_list_tail(evlist, &head);
284
285         return 0;
286
287 out_delete_partial_list:
288         __evlist__for_each_entry_safe(&head, n, evsel)
289                 perf_evsel__delete(evsel);
290         return -1;
291 }
292
293 int __perf_evlist__add_default_attrs(struct perf_evlist *evlist,
294                                      struct perf_event_attr *attrs, size_t nr_attrs)
295 {
296         size_t i;
297
298         for (i = 0; i < nr_attrs; i++)
299                 event_attr_init(attrs + i);
300
301         return perf_evlist__add_attrs(evlist, attrs, nr_attrs);
302 }
303
304 struct perf_evsel *
305 perf_evlist__find_tracepoint_by_id(struct perf_evlist *evlist, int id)
306 {
307         struct perf_evsel *evsel;
308
309         evlist__for_each_entry(evlist, evsel) {
310                 if (evsel->attr.type   == PERF_TYPE_TRACEPOINT &&
311                     (int)evsel->attr.config == id)
312                         return evsel;
313         }
314
315         return NULL;
316 }
317
318 struct perf_evsel *
319 perf_evlist__find_tracepoint_by_name(struct perf_evlist *evlist,
320                                      const char *name)
321 {
322         struct perf_evsel *evsel;
323
324         evlist__for_each_entry(evlist, evsel) {
325                 if ((evsel->attr.type == PERF_TYPE_TRACEPOINT) &&
326                     (strcmp(evsel->name, name) == 0))
327                         return evsel;
328         }
329
330         return NULL;
331 }
332
333 int perf_evlist__add_newtp(struct perf_evlist *evlist,
334                            const char *sys, const char *name, void *handler)
335 {
336         struct perf_evsel *evsel = perf_evsel__newtp(sys, name);
337
338         if (IS_ERR(evsel))
339                 return -1;
340
341         evsel->handler = handler;
342         perf_evlist__add(evlist, evsel);
343         return 0;
344 }
345
346 static int perf_evlist__nr_threads(struct perf_evlist *evlist,
347                                    struct perf_evsel *evsel)
348 {
349         if (evsel->system_wide)
350                 return 1;
351         else
352                 return thread_map__nr(evlist->threads);
353 }
354
355 void perf_evlist__disable(struct perf_evlist *evlist)
356 {
357         struct perf_evsel *pos;
358
359         evlist__for_each_entry(evlist, pos) {
360                 if (!perf_evsel__is_group_leader(pos) || !pos->fd)
361                         continue;
362                 perf_evsel__disable(pos);
363         }
364
365         evlist->enabled = false;
366 }
367
368 void perf_evlist__enable(struct perf_evlist *evlist)
369 {
370         struct perf_evsel *pos;
371
372         evlist__for_each_entry(evlist, pos) {
373                 if (!perf_evsel__is_group_leader(pos) || !pos->fd)
374                         continue;
375                 perf_evsel__enable(pos);
376         }
377
378         evlist->enabled = true;
379 }
380
381 void perf_evlist__toggle_enable(struct perf_evlist *evlist)
382 {
383         (evlist->enabled ? perf_evlist__disable : perf_evlist__enable)(evlist);
384 }
385
386 static int perf_evlist__enable_event_cpu(struct perf_evlist *evlist,
387                                          struct perf_evsel *evsel, int cpu)
388 {
389         int thread;
390         int nr_threads = perf_evlist__nr_threads(evlist, evsel);
391
392         if (!evsel->fd)
393                 return -EINVAL;
394
395         for (thread = 0; thread < nr_threads; thread++) {
396                 int err = ioctl(FD(evsel, cpu, thread), PERF_EVENT_IOC_ENABLE, 0);
397                 if (err)
398                         return err;
399         }
400         return 0;
401 }
402
403 static int perf_evlist__enable_event_thread(struct perf_evlist *evlist,
404                                             struct perf_evsel *evsel,
405                                             int thread)
406 {
407         int cpu;
408         int nr_cpus = cpu_map__nr(evlist->cpus);
409
410         if (!evsel->fd)
411                 return -EINVAL;
412
413         for (cpu = 0; cpu < nr_cpus; cpu++) {
414                 int err = ioctl(FD(evsel, cpu, thread), PERF_EVENT_IOC_ENABLE, 0);
415                 if (err)
416                         return err;
417         }
418         return 0;
419 }
420
421 int perf_evlist__enable_event_idx(struct perf_evlist *evlist,
422                                   struct perf_evsel *evsel, int idx)
423 {
424         bool per_cpu_mmaps = !cpu_map__empty(evlist->cpus);
425
426         if (per_cpu_mmaps)
427                 return perf_evlist__enable_event_cpu(evlist, evsel, idx);
428         else
429                 return perf_evlist__enable_event_thread(evlist, evsel, idx);
430 }
431
432 int perf_evlist__alloc_pollfd(struct perf_evlist *evlist)
433 {
434         int nr_cpus = cpu_map__nr(evlist->cpus);
435         int nr_threads = thread_map__nr(evlist->threads);
436         int nfds = 0;
437         struct perf_evsel *evsel;
438
439         evlist__for_each_entry(evlist, evsel) {
440                 if (evsel->system_wide)
441                         nfds += nr_cpus;
442                 else
443                         nfds += nr_cpus * nr_threads;
444         }
445
446         if (fdarray__available_entries(&evlist->pollfd) < nfds &&
447             fdarray__grow(&evlist->pollfd, nfds) < 0)
448                 return -ENOMEM;
449
450         return 0;
451 }
452
453 static int __perf_evlist__add_pollfd(struct perf_evlist *evlist, int fd,
454                                      struct perf_mmap *map, short revent)
455 {
456         int pos = fdarray__add(&evlist->pollfd, fd, revent | POLLERR | POLLHUP);
457         /*
458          * Save the idx so that when we filter out fds POLLHUP'ed we can
459          * close the associated evlist->mmap[] entry.
460          */
461         if (pos >= 0) {
462                 evlist->pollfd.priv[pos].ptr = map;
463
464                 fcntl(fd, F_SETFL, O_NONBLOCK);
465         }
466
467         return pos;
468 }
469
470 int perf_evlist__add_pollfd(struct perf_evlist *evlist, int fd)
471 {
472         return __perf_evlist__add_pollfd(evlist, fd, NULL, POLLIN);
473 }
474
475 static void perf_evlist__munmap_filtered(struct fdarray *fda, int fd,
476                                          void *arg __maybe_unused)
477 {
478         struct perf_mmap *map = fda->priv[fd].ptr;
479
480         if (map)
481                 perf_mmap__put(map);
482 }
483
484 int perf_evlist__filter_pollfd(struct perf_evlist *evlist, short revents_and_mask)
485 {
486         return fdarray__filter(&evlist->pollfd, revents_and_mask,
487                                perf_evlist__munmap_filtered, NULL);
488 }
489
490 int perf_evlist__poll(struct perf_evlist *evlist, int timeout)
491 {
492         return fdarray__poll(&evlist->pollfd, timeout);
493 }
494
495 static void perf_evlist__id_hash(struct perf_evlist *evlist,
496                                  struct perf_evsel *evsel,
497                                  int cpu, int thread, u64 id)
498 {
499         int hash;
500         struct perf_sample_id *sid = SID(evsel, cpu, thread);
501
502         sid->id = id;
503         sid->evsel = evsel;
504         hash = hash_64(sid->id, PERF_EVLIST__HLIST_BITS);
505         hlist_add_head(&sid->node, &evlist->heads[hash]);
506 }
507
508 void perf_evlist__id_add(struct perf_evlist *evlist, struct perf_evsel *evsel,
509                          int cpu, int thread, u64 id)
510 {
511         perf_evlist__id_hash(evlist, evsel, cpu, thread, id);
512         evsel->id[evsel->ids++] = id;
513 }
514
515 int perf_evlist__id_add_fd(struct perf_evlist *evlist,
516                            struct perf_evsel *evsel,
517                            int cpu, int thread, int fd)
518 {
519         u64 read_data[4] = { 0, };
520         int id_idx = 1; /* The first entry is the counter value */
521         u64 id;
522         int ret;
523
524         ret = ioctl(fd, PERF_EVENT_IOC_ID, &id);
525         if (!ret)
526                 goto add;
527
528         if (errno != ENOTTY)
529                 return -1;
530
531         /* Legacy way to get event id.. All hail to old kernels! */
532
533         /*
534          * This way does not work with group format read, so bail
535          * out in that case.
536          */
537         if (perf_evlist__read_format(evlist) & PERF_FORMAT_GROUP)
538                 return -1;
539
540         if (!(evsel->attr.read_format & PERF_FORMAT_ID) ||
541             read(fd, &read_data, sizeof(read_data)) == -1)
542                 return -1;
543
544         if (evsel->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
545                 ++id_idx;
546         if (evsel->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
547                 ++id_idx;
548
549         id = read_data[id_idx];
550
551  add:
552         perf_evlist__id_add(evlist, evsel, cpu, thread, id);
553         return 0;
554 }
555
556 static void perf_evlist__set_sid_idx(struct perf_evlist *evlist,
557                                      struct perf_evsel *evsel, int idx, int cpu,
558                                      int thread)
559 {
560         struct perf_sample_id *sid = SID(evsel, cpu, thread);
561         sid->idx = idx;
562         if (evlist->cpus && cpu >= 0)
563                 sid->cpu = evlist->cpus->map[cpu];
564         else
565                 sid->cpu = -1;
566         if (!evsel->system_wide && evlist->threads && thread >= 0)
567                 sid->tid = thread_map__pid(evlist->threads, thread);
568         else
569                 sid->tid = -1;
570 }
571
572 struct perf_sample_id *perf_evlist__id2sid(struct perf_evlist *evlist, u64 id)
573 {
574         struct hlist_head *head;
575         struct perf_sample_id *sid;
576         int hash;
577
578         hash = hash_64(id, PERF_EVLIST__HLIST_BITS);
579         head = &evlist->heads[hash];
580
581         hlist_for_each_entry(sid, head, node)
582                 if (sid->id == id)
583                         return sid;
584
585         return NULL;
586 }
587
588 struct perf_evsel *perf_evlist__id2evsel(struct perf_evlist *evlist, u64 id)
589 {
590         struct perf_sample_id *sid;
591
592         if (evlist->nr_entries == 1 || !id)
593                 return perf_evlist__first(evlist);
594
595         sid = perf_evlist__id2sid(evlist, id);
596         if (sid)
597                 return sid->evsel;
598
599         if (!perf_evlist__sample_id_all(evlist))
600                 return perf_evlist__first(evlist);
601
602         return NULL;
603 }
604
605 struct perf_evsel *perf_evlist__id2evsel_strict(struct perf_evlist *evlist,
606                                                 u64 id)
607 {
608         struct perf_sample_id *sid;
609
610         if (!id)
611                 return NULL;
612
613         sid = perf_evlist__id2sid(evlist, id);
614         if (sid)
615                 return sid->evsel;
616
617         return NULL;
618 }
619
620 static int perf_evlist__event2id(struct perf_evlist *evlist,
621                                  union perf_event *event, u64 *id)
622 {
623         const u64 *array = event->sample.array;
624         ssize_t n;
625
626         n = (event->header.size - sizeof(event->header)) >> 3;
627
628         if (event->header.type == PERF_RECORD_SAMPLE) {
629                 if (evlist->id_pos >= n)
630                         return -1;
631                 *id = array[evlist->id_pos];
632         } else {
633                 if (evlist->is_pos > n)
634                         return -1;
635                 n -= evlist->is_pos;
636                 *id = array[n];
637         }
638         return 0;
639 }
640
641 struct perf_evsel *perf_evlist__event2evsel(struct perf_evlist *evlist,
642                                             union perf_event *event)
643 {
644         struct perf_evsel *first = perf_evlist__first(evlist);
645         struct hlist_head *head;
646         struct perf_sample_id *sid;
647         int hash;
648         u64 id;
649
650         if (evlist->nr_entries == 1)
651                 return first;
652
653         if (!first->attr.sample_id_all &&
654             event->header.type != PERF_RECORD_SAMPLE)
655                 return first;
656
657         if (perf_evlist__event2id(evlist, event, &id))
658                 return NULL;
659
660         /* Synthesized events have an id of zero */
661         if (!id)
662                 return first;
663
664         hash = hash_64(id, PERF_EVLIST__HLIST_BITS);
665         head = &evlist->heads[hash];
666
667         hlist_for_each_entry(sid, head, node) {
668                 if (sid->id == id)
669                         return sid->evsel;
670         }
671         return NULL;
672 }
673
674 static int perf_evlist__set_paused(struct perf_evlist *evlist, bool value)
675 {
676         int i;
677
678         if (!evlist->overwrite_mmap)
679                 return 0;
680
681         for (i = 0; i < evlist->nr_mmaps; i++) {
682                 int fd = evlist->overwrite_mmap[i].fd;
683                 int err;
684
685                 if (fd < 0)
686                         continue;
687                 err = ioctl(fd, PERF_EVENT_IOC_PAUSE_OUTPUT, value ? 1 : 0);
688                 if (err)
689                         return err;
690         }
691         return 0;
692 }
693
694 static int perf_evlist__pause(struct perf_evlist *evlist)
695 {
696         return perf_evlist__set_paused(evlist, true);
697 }
698
699 static int perf_evlist__resume(struct perf_evlist *evlist)
700 {
701         return perf_evlist__set_paused(evlist, false);
702 }
703
704 union perf_event *perf_evlist__mmap_read_forward(struct perf_evlist *evlist, int idx)
705 {
706         struct perf_mmap *md = &evlist->mmap[idx];
707
708         /*
709          * Check messup is required for forward overwritable ring buffer:
710          * memory pointed by md->prev can be overwritten in this case.
711          * No need for read-write ring buffer: kernel stop outputting when
712          * it hit md->prev (perf_mmap__consume()).
713          */
714         return perf_mmap__read_forward(md);
715 }
716
717 union perf_event *perf_evlist__mmap_read_backward(struct perf_evlist *evlist, int idx)
718 {
719         struct perf_mmap *md = &evlist->mmap[idx];
720
721         /*
722          * No need to check messup for backward ring buffer:
723          * We can always read arbitrary long data from a backward
724          * ring buffer unless we forget to pause it before reading.
725          */
726         return perf_mmap__read_backward(md);
727 }
728
729 union perf_event *perf_evlist__mmap_read(struct perf_evlist *evlist, int idx)
730 {
731         return perf_evlist__mmap_read_forward(evlist, idx);
732 }
733
734 void perf_evlist__mmap_read_catchup(struct perf_evlist *evlist, int idx)
735 {
736         perf_mmap__read_catchup(&evlist->mmap[idx]);
737 }
738
739 void perf_evlist__mmap_consume(struct perf_evlist *evlist, int idx)
740 {
741         perf_mmap__consume(&evlist->mmap[idx], false);
742 }
743
744 static void perf_evlist__munmap_nofree(struct perf_evlist *evlist)
745 {
746         int i;
747
748         if (evlist->mmap)
749                 for (i = 0; i < evlist->nr_mmaps; i++)
750                         perf_mmap__munmap(&evlist->mmap[i]);
751
752         if (evlist->overwrite_mmap)
753                 for (i = 0; i < evlist->nr_mmaps; i++)
754                         perf_mmap__munmap(&evlist->overwrite_mmap[i]);
755 }
756
757 void perf_evlist__munmap(struct perf_evlist *evlist)
758 {
759         perf_evlist__munmap_nofree(evlist);
760         zfree(&evlist->mmap);
761         zfree(&evlist->overwrite_mmap);
762 }
763
764 static struct perf_mmap *perf_evlist__alloc_mmap(struct perf_evlist *evlist)
765 {
766         int i;
767         struct perf_mmap *map;
768
769         evlist->nr_mmaps = cpu_map__nr(evlist->cpus);
770         if (cpu_map__empty(evlist->cpus))
771                 evlist->nr_mmaps = thread_map__nr(evlist->threads);
772         map = zalloc(evlist->nr_mmaps * sizeof(struct perf_mmap));
773         if (!map)
774                 return NULL;
775
776         for (i = 0; i < evlist->nr_mmaps; i++) {
777                 map[i].fd = -1;
778                 /*
779                  * When the perf_mmap() call is made we grab one refcount, plus
780                  * one extra to let perf_evlist__mmap_consume() get the last
781                  * events after all real references (perf_mmap__get()) are
782                  * dropped.
783                  *
784                  * Each PERF_EVENT_IOC_SET_OUTPUT points to this mmap and
785                  * thus does perf_mmap__get() on it.
786                  */
787                 refcount_set(&map[i].refcnt, 0);
788         }
789         return map;
790 }
791
792 static bool
793 perf_evlist__should_poll(struct perf_evlist *evlist __maybe_unused,
794                          struct perf_evsel *evsel)
795 {
796         if (evsel->attr.write_backward)
797                 return false;
798         return true;
799 }
800
801 static int perf_evlist__mmap_per_evsel(struct perf_evlist *evlist, int idx,
802                                        struct mmap_params *mp, int cpu_idx,
803                                        int thread, int *_output, int *_output_overwrite)
804 {
805         struct perf_evsel *evsel;
806         int revent;
807         int evlist_cpu = cpu_map__cpu(evlist->cpus, cpu_idx);
808
809         evlist__for_each_entry(evlist, evsel) {
810                 struct perf_mmap *maps = evlist->mmap;
811                 int *output = _output;
812                 int fd;
813                 int cpu;
814
815                 mp->prot = PROT_READ | PROT_WRITE;
816                 if (evsel->attr.write_backward) {
817                         output = _output_overwrite;
818                         maps = evlist->overwrite_mmap;
819
820                         if (!maps) {
821                                 maps = perf_evlist__alloc_mmap(evlist);
822                                 if (!maps)
823                                         return -1;
824                                 evlist->overwrite_mmap = maps;
825                                 if (evlist->bkw_mmap_state == BKW_MMAP_NOTREADY)
826                                         perf_evlist__toggle_bkw_mmap(evlist, BKW_MMAP_RUNNING);
827                         }
828                         mp->prot &= ~PROT_WRITE;
829                 }
830
831                 if (evsel->system_wide && thread)
832                         continue;
833
834                 cpu = cpu_map__idx(evsel->cpus, evlist_cpu);
835                 if (cpu == -1)
836                         continue;
837
838                 fd = FD(evsel, cpu, thread);
839
840                 if (*output == -1) {
841                         *output = fd;
842
843                         if (perf_mmap__mmap(&maps[idx], mp, *output)  < 0)
844                                 return -1;
845                 } else {
846                         if (ioctl(fd, PERF_EVENT_IOC_SET_OUTPUT, *output) != 0)
847                                 return -1;
848
849                         perf_mmap__get(&maps[idx]);
850                 }
851
852                 revent = perf_evlist__should_poll(evlist, evsel) ? POLLIN : 0;
853
854                 /*
855                  * The system_wide flag causes a selected event to be opened
856                  * always without a pid.  Consequently it will never get a
857                  * POLLHUP, but it is used for tracking in combination with
858                  * other events, so it should not need to be polled anyway.
859                  * Therefore don't add it for polling.
860                  */
861                 if (!evsel->system_wide &&
862                     __perf_evlist__add_pollfd(evlist, fd, &maps[idx], revent) < 0) {
863                         perf_mmap__put(&maps[idx]);
864                         return -1;
865                 }
866
867                 if (evsel->attr.read_format & PERF_FORMAT_ID) {
868                         if (perf_evlist__id_add_fd(evlist, evsel, cpu, thread,
869                                                    fd) < 0)
870                                 return -1;
871                         perf_evlist__set_sid_idx(evlist, evsel, idx, cpu,
872                                                  thread);
873                 }
874         }
875
876         return 0;
877 }
878
879 static int perf_evlist__mmap_per_cpu(struct perf_evlist *evlist,
880                                      struct mmap_params *mp)
881 {
882         int cpu, thread;
883         int nr_cpus = cpu_map__nr(evlist->cpus);
884         int nr_threads = thread_map__nr(evlist->threads);
885
886         pr_debug2("perf event ring buffer mmapped per cpu\n");
887         for (cpu = 0; cpu < nr_cpus; cpu++) {
888                 int output = -1;
889                 int output_overwrite = -1;
890
891                 auxtrace_mmap_params__set_idx(&mp->auxtrace_mp, evlist, cpu,
892                                               true);
893
894                 for (thread = 0; thread < nr_threads; thread++) {
895                         if (perf_evlist__mmap_per_evsel(evlist, cpu, mp, cpu,
896                                                         thread, &output, &output_overwrite))
897                                 goto out_unmap;
898                 }
899         }
900
901         return 0;
902
903 out_unmap:
904         perf_evlist__munmap_nofree(evlist);
905         return -1;
906 }
907
908 static int perf_evlist__mmap_per_thread(struct perf_evlist *evlist,
909                                         struct mmap_params *mp)
910 {
911         int thread;
912         int nr_threads = thread_map__nr(evlist->threads);
913
914         pr_debug2("perf event ring buffer mmapped per thread\n");
915         for (thread = 0; thread < nr_threads; thread++) {
916                 int output = -1;
917                 int output_overwrite = -1;
918
919                 auxtrace_mmap_params__set_idx(&mp->auxtrace_mp, evlist, thread,
920                                               false);
921
922                 if (perf_evlist__mmap_per_evsel(evlist, thread, mp, 0, thread,
923                                                 &output, &output_overwrite))
924                         goto out_unmap;
925         }
926
927         return 0;
928
929 out_unmap:
930         perf_evlist__munmap_nofree(evlist);
931         return -1;
932 }
933
934 unsigned long perf_event_mlock_kb_in_pages(void)
935 {
936         unsigned long pages;
937         int max;
938
939         if (sysctl__read_int("kernel/perf_event_mlock_kb", &max) < 0) {
940                 /*
941                  * Pick a once upon a time good value, i.e. things look
942                  * strange since we can't read a sysctl value, but lets not
943                  * die yet...
944                  */
945                 max = 512;
946         } else {
947                 max -= (page_size / 1024);
948         }
949
950         pages = (max * 1024) / page_size;
951         if (!is_power_of_2(pages))
952                 pages = rounddown_pow_of_two(pages);
953
954         return pages;
955 }
956
957 size_t perf_evlist__mmap_size(unsigned long pages)
958 {
959         if (pages == UINT_MAX)
960                 pages = perf_event_mlock_kb_in_pages();
961         else if (!is_power_of_2(pages))
962                 return 0;
963
964         return (pages + 1) * page_size;
965 }
966
967 static long parse_pages_arg(const char *str, unsigned long min,
968                             unsigned long max)
969 {
970         unsigned long pages, val;
971         static struct parse_tag tags[] = {
972                 { .tag  = 'B', .mult = 1       },
973                 { .tag  = 'K', .mult = 1 << 10 },
974                 { .tag  = 'M', .mult = 1 << 20 },
975                 { .tag  = 'G', .mult = 1 << 30 },
976                 { .tag  = 0 },
977         };
978
979         if (str == NULL)
980                 return -EINVAL;
981
982         val = parse_tag_value(str, tags);
983         if (val != (unsigned long) -1) {
984                 /* we got file size value */
985                 pages = PERF_ALIGN(val, page_size) / page_size;
986         } else {
987                 /* we got pages count value */
988                 char *eptr;
989                 pages = strtoul(str, &eptr, 10);
990                 if (*eptr != '\0')
991                         return -EINVAL;
992         }
993
994         if (pages == 0 && min == 0) {
995                 /* leave number of pages at 0 */
996         } else if (!is_power_of_2(pages)) {
997                 char buf[100];
998
999                 /* round pages up to next power of 2 */
1000                 pages = roundup_pow_of_two(pages);
1001                 if (!pages)
1002                         return -EINVAL;
1003
1004                 unit_number__scnprintf(buf, sizeof(buf), pages * page_size);
1005                 pr_info("rounding mmap pages size to %s (%lu pages)\n",
1006                         buf, pages);
1007         }
1008
1009         if (pages > max)
1010                 return -EINVAL;
1011
1012         return pages;
1013 }
1014
1015 int __perf_evlist__parse_mmap_pages(unsigned int *mmap_pages, const char *str)
1016 {
1017         unsigned long max = UINT_MAX;
1018         long pages;
1019
1020         if (max > SIZE_MAX / page_size)
1021                 max = SIZE_MAX / page_size;
1022
1023         pages = parse_pages_arg(str, 1, max);
1024         if (pages < 0) {
1025                 pr_err("Invalid argument for --mmap_pages/-m\n");
1026                 return -1;
1027         }
1028
1029         *mmap_pages = pages;
1030         return 0;
1031 }
1032
1033 int perf_evlist__parse_mmap_pages(const struct option *opt, const char *str,
1034                                   int unset __maybe_unused)
1035 {
1036         return __perf_evlist__parse_mmap_pages(opt->value, str);
1037 }
1038
1039 /**
1040  * perf_evlist__mmap_ex - Create mmaps to receive events.
1041  * @evlist: list of events
1042  * @pages: map length in pages
1043  * @overwrite: overwrite older events?
1044  * @auxtrace_pages - auxtrace map length in pages
1045  * @auxtrace_overwrite - overwrite older auxtrace data?
1046  *
1047  * If @overwrite is %false the user needs to signal event consumption using
1048  * perf_mmap__write_tail().  Using perf_evlist__mmap_read() does this
1049  * automatically.
1050  *
1051  * Similarly, if @auxtrace_overwrite is %false the user needs to signal data
1052  * consumption using auxtrace_mmap__write_tail().
1053  *
1054  * Return: %0 on success, negative error code otherwise.
1055  */
1056 int perf_evlist__mmap_ex(struct perf_evlist *evlist, unsigned int pages,
1057                          unsigned int auxtrace_pages,
1058                          bool auxtrace_overwrite)
1059 {
1060         struct perf_evsel *evsel;
1061         const struct cpu_map *cpus = evlist->cpus;
1062         const struct thread_map *threads = evlist->threads;
1063         /*
1064          * Delay setting mp.prot: set it before calling perf_mmap__mmap.
1065          * Its value is decided by evsel's write_backward.
1066          * So &mp should not be passed through const pointer.
1067          */
1068         struct mmap_params mp;
1069
1070         if (!evlist->mmap)
1071                 evlist->mmap = perf_evlist__alloc_mmap(evlist);
1072         if (!evlist->mmap)
1073                 return -ENOMEM;
1074
1075         if (evlist->pollfd.entries == NULL && perf_evlist__alloc_pollfd(evlist) < 0)
1076                 return -ENOMEM;
1077
1078         evlist->mmap_len = perf_evlist__mmap_size(pages);
1079         pr_debug("mmap size %zuB\n", evlist->mmap_len);
1080         mp.mask = evlist->mmap_len - page_size - 1;
1081
1082         auxtrace_mmap_params__init(&mp.auxtrace_mp, evlist->mmap_len,
1083                                    auxtrace_pages, auxtrace_overwrite);
1084
1085         evlist__for_each_entry(evlist, evsel) {
1086                 if ((evsel->attr.read_format & PERF_FORMAT_ID) &&
1087                     evsel->sample_id == NULL &&
1088                     perf_evsel__alloc_id(evsel, cpu_map__nr(cpus), threads->nr) < 0)
1089                         return -ENOMEM;
1090         }
1091
1092         if (cpu_map__empty(cpus))
1093                 return perf_evlist__mmap_per_thread(evlist, &mp);
1094
1095         return perf_evlist__mmap_per_cpu(evlist, &mp);
1096 }
1097
1098 int perf_evlist__mmap(struct perf_evlist *evlist, unsigned int pages)
1099 {
1100         return perf_evlist__mmap_ex(evlist, pages, 0, false);
1101 }
1102
1103 int perf_evlist__create_maps(struct perf_evlist *evlist, struct target *target)
1104 {
1105         struct cpu_map *cpus;
1106         struct thread_map *threads;
1107
1108         threads = thread_map__new_str(target->pid, target->tid, target->uid,
1109                                       target->per_thread);
1110
1111         if (!threads)
1112                 return -1;
1113
1114         if (target__uses_dummy_map(target))
1115                 cpus = cpu_map__dummy_new();
1116         else
1117                 cpus = cpu_map__new(target->cpu_list);
1118
1119         if (!cpus)
1120                 goto out_delete_threads;
1121
1122         evlist->has_user_cpus = !!target->cpu_list;
1123
1124         perf_evlist__set_maps(evlist, cpus, threads);
1125
1126         return 0;
1127
1128 out_delete_threads:
1129         thread_map__put(threads);
1130         return -1;
1131 }
1132
1133 void perf_evlist__set_maps(struct perf_evlist *evlist, struct cpu_map *cpus,
1134                            struct thread_map *threads)
1135 {
1136         /*
1137          * Allow for the possibility that one or another of the maps isn't being
1138          * changed i.e. don't put it.  Note we are assuming the maps that are
1139          * being applied are brand new and evlist is taking ownership of the
1140          * original reference count of 1.  If that is not the case it is up to
1141          * the caller to increase the reference count.
1142          */
1143         if (cpus != evlist->cpus) {
1144                 cpu_map__put(evlist->cpus);
1145                 evlist->cpus = cpu_map__get(cpus);
1146         }
1147
1148         if (threads != evlist->threads) {
1149                 thread_map__put(evlist->threads);
1150                 evlist->threads = thread_map__get(threads);
1151         }
1152
1153         perf_evlist__propagate_maps(evlist);
1154 }
1155
1156 void __perf_evlist__set_sample_bit(struct perf_evlist *evlist,
1157                                    enum perf_event_sample_format bit)
1158 {
1159         struct perf_evsel *evsel;
1160
1161         evlist__for_each_entry(evlist, evsel)
1162                 __perf_evsel__set_sample_bit(evsel, bit);
1163 }
1164
1165 void __perf_evlist__reset_sample_bit(struct perf_evlist *evlist,
1166                                      enum perf_event_sample_format bit)
1167 {
1168         struct perf_evsel *evsel;
1169
1170         evlist__for_each_entry(evlist, evsel)
1171                 __perf_evsel__reset_sample_bit(evsel, bit);
1172 }
1173
1174 int perf_evlist__apply_filters(struct perf_evlist *evlist, struct perf_evsel **err_evsel)
1175 {
1176         struct perf_evsel *evsel;
1177         int err = 0;
1178
1179         evlist__for_each_entry(evlist, evsel) {
1180                 if (evsel->filter == NULL)
1181                         continue;
1182
1183                 /*
1184                  * filters only work for tracepoint event, which doesn't have cpu limit.
1185                  * So evlist and evsel should always be same.
1186                  */
1187                 err = perf_evsel__apply_filter(evsel, evsel->filter);
1188                 if (err) {
1189                         *err_evsel = evsel;
1190                         break;
1191                 }
1192         }
1193
1194         return err;
1195 }
1196
1197 int perf_evlist__set_filter(struct perf_evlist *evlist, const char *filter)
1198 {
1199         struct perf_evsel *evsel;
1200         int err = 0;
1201
1202         evlist__for_each_entry(evlist, evsel) {
1203                 if (evsel->attr.type != PERF_TYPE_TRACEPOINT)
1204                         continue;
1205
1206                 err = perf_evsel__set_filter(evsel, filter);
1207                 if (err)
1208                         break;
1209         }
1210
1211         return err;
1212 }
1213
1214 int perf_evlist__set_filter_pids(struct perf_evlist *evlist, size_t npids, pid_t *pids)
1215 {
1216         char *filter;
1217         int ret = -1;
1218         size_t i;
1219
1220         for (i = 0; i < npids; ++i) {
1221                 if (i == 0) {
1222                         if (asprintf(&filter, "common_pid != %d", pids[i]) < 0)
1223                                 return -1;
1224                 } else {
1225                         char *tmp;
1226
1227                         if (asprintf(&tmp, "%s && common_pid != %d", filter, pids[i]) < 0)
1228                                 goto out_free;
1229
1230                         free(filter);
1231                         filter = tmp;
1232                 }
1233         }
1234
1235         ret = perf_evlist__set_filter(evlist, filter);
1236 out_free:
1237         free(filter);
1238         return ret;
1239 }
1240
1241 int perf_evlist__set_filter_pid(struct perf_evlist *evlist, pid_t pid)
1242 {
1243         return perf_evlist__set_filter_pids(evlist, 1, &pid);
1244 }
1245
1246 bool perf_evlist__valid_sample_type(struct perf_evlist *evlist)
1247 {
1248         struct perf_evsel *pos;
1249
1250         if (evlist->nr_entries == 1)
1251                 return true;
1252
1253         if (evlist->id_pos < 0 || evlist->is_pos < 0)
1254                 return false;
1255
1256         evlist__for_each_entry(evlist, pos) {
1257                 if (pos->id_pos != evlist->id_pos ||
1258                     pos->is_pos != evlist->is_pos)
1259                         return false;
1260         }
1261
1262         return true;
1263 }
1264
1265 u64 __perf_evlist__combined_sample_type(struct perf_evlist *evlist)
1266 {
1267         struct perf_evsel *evsel;
1268
1269         if (evlist->combined_sample_type)
1270                 return evlist->combined_sample_type;
1271
1272         evlist__for_each_entry(evlist, evsel)
1273                 evlist->combined_sample_type |= evsel->attr.sample_type;
1274
1275         return evlist->combined_sample_type;
1276 }
1277
1278 u64 perf_evlist__combined_sample_type(struct perf_evlist *evlist)
1279 {
1280         evlist->combined_sample_type = 0;
1281         return __perf_evlist__combined_sample_type(evlist);
1282 }
1283
1284 u64 perf_evlist__combined_branch_type(struct perf_evlist *evlist)
1285 {
1286         struct perf_evsel *evsel;
1287         u64 branch_type = 0;
1288
1289         evlist__for_each_entry(evlist, evsel)
1290                 branch_type |= evsel->attr.branch_sample_type;
1291         return branch_type;
1292 }
1293
1294 bool perf_evlist__valid_read_format(struct perf_evlist *evlist)
1295 {
1296         struct perf_evsel *first = perf_evlist__first(evlist), *pos = first;
1297         u64 read_format = first->attr.read_format;
1298         u64 sample_type = first->attr.sample_type;
1299
1300         evlist__for_each_entry(evlist, pos) {
1301                 if (read_format != pos->attr.read_format)
1302                         return false;
1303         }
1304
1305         /* PERF_SAMPLE_READ imples PERF_FORMAT_ID. */
1306         if ((sample_type & PERF_SAMPLE_READ) &&
1307             !(read_format & PERF_FORMAT_ID)) {
1308                 return false;
1309         }
1310
1311         return true;
1312 }
1313
1314 u64 perf_evlist__read_format(struct perf_evlist *evlist)
1315 {
1316         struct perf_evsel *first = perf_evlist__first(evlist);
1317         return first->attr.read_format;
1318 }
1319
1320 u16 perf_evlist__id_hdr_size(struct perf_evlist *evlist)
1321 {
1322         struct perf_evsel *first = perf_evlist__first(evlist);
1323         struct perf_sample *data;
1324         u64 sample_type;
1325         u16 size = 0;
1326
1327         if (!first->attr.sample_id_all)
1328                 goto out;
1329
1330         sample_type = first->attr.sample_type;
1331
1332         if (sample_type & PERF_SAMPLE_TID)
1333                 size += sizeof(data->tid) * 2;
1334
1335        if (sample_type & PERF_SAMPLE_TIME)
1336                 size += sizeof(data->time);
1337
1338         if (sample_type & PERF_SAMPLE_ID)
1339                 size += sizeof(data->id);
1340
1341         if (sample_type & PERF_SAMPLE_STREAM_ID)
1342                 size += sizeof(data->stream_id);
1343
1344         if (sample_type & PERF_SAMPLE_CPU)
1345                 size += sizeof(data->cpu) * 2;
1346
1347         if (sample_type & PERF_SAMPLE_IDENTIFIER)
1348                 size += sizeof(data->id);
1349 out:
1350         return size;
1351 }
1352
1353 bool perf_evlist__valid_sample_id_all(struct perf_evlist *evlist)
1354 {
1355         struct perf_evsel *first = perf_evlist__first(evlist), *pos = first;
1356
1357         evlist__for_each_entry_continue(evlist, pos) {
1358                 if (first->attr.sample_id_all != pos->attr.sample_id_all)
1359                         return false;
1360         }
1361
1362         return true;
1363 }
1364
1365 bool perf_evlist__sample_id_all(struct perf_evlist *evlist)
1366 {
1367         struct perf_evsel *first = perf_evlist__first(evlist);
1368         return first->attr.sample_id_all;
1369 }
1370
1371 void perf_evlist__set_selected(struct perf_evlist *evlist,
1372                                struct perf_evsel *evsel)
1373 {
1374         evlist->selected = evsel;
1375 }
1376
1377 void perf_evlist__close(struct perf_evlist *evlist)
1378 {
1379         struct perf_evsel *evsel;
1380
1381         evlist__for_each_entry_reverse(evlist, evsel)
1382                 perf_evsel__close(evsel);
1383 }
1384
1385 static int perf_evlist__create_syswide_maps(struct perf_evlist *evlist)
1386 {
1387         struct cpu_map    *cpus;
1388         struct thread_map *threads;
1389         int err = -ENOMEM;
1390
1391         /*
1392          * Try reading /sys/devices/system/cpu/online to get
1393          * an all cpus map.
1394          *
1395          * FIXME: -ENOMEM is the best we can do here, the cpu_map
1396          * code needs an overhaul to properly forward the
1397          * error, and we may not want to do that fallback to a
1398          * default cpu identity map :-\
1399          */
1400         cpus = cpu_map__new(NULL);
1401         if (!cpus)
1402                 goto out;
1403
1404         threads = thread_map__new_dummy();
1405         if (!threads)
1406                 goto out_put;
1407
1408         perf_evlist__set_maps(evlist, cpus, threads);
1409 out:
1410         return err;
1411 out_put:
1412         cpu_map__put(cpus);
1413         goto out;
1414 }
1415
1416 int perf_evlist__open(struct perf_evlist *evlist)
1417 {
1418         struct perf_evsel *evsel;
1419         int err;
1420
1421         /*
1422          * Default: one fd per CPU, all threads, aka systemwide
1423          * as sys_perf_event_open(cpu = -1, thread = -1) is EINVAL
1424          */
1425         if (evlist->threads == NULL && evlist->cpus == NULL) {
1426                 err = perf_evlist__create_syswide_maps(evlist);
1427                 if (err < 0)
1428                         goto out_err;
1429         }
1430
1431         perf_evlist__update_id_pos(evlist);
1432
1433         evlist__for_each_entry(evlist, evsel) {
1434                 err = perf_evsel__open(evsel, evsel->cpus, evsel->threads);
1435                 if (err < 0)
1436                         goto out_err;
1437         }
1438
1439         return 0;
1440 out_err:
1441         perf_evlist__close(evlist);
1442         errno = -err;
1443         return err;
1444 }
1445
1446 int perf_evlist__prepare_workload(struct perf_evlist *evlist, struct target *target,
1447                                   const char *argv[], bool pipe_output,
1448                                   void (*exec_error)(int signo, siginfo_t *info, void *ucontext))
1449 {
1450         int child_ready_pipe[2], go_pipe[2];
1451         char bf;
1452
1453         if (pipe(child_ready_pipe) < 0) {
1454                 perror("failed to create 'ready' pipe");
1455                 return -1;
1456         }
1457
1458         if (pipe(go_pipe) < 0) {
1459                 perror("failed to create 'go' pipe");
1460                 goto out_close_ready_pipe;
1461         }
1462
1463         evlist->workload.pid = fork();
1464         if (evlist->workload.pid < 0) {
1465                 perror("failed to fork");
1466                 goto out_close_pipes;
1467         }
1468
1469         if (!evlist->workload.pid) {
1470                 int ret;
1471
1472                 if (pipe_output)
1473                         dup2(2, 1);
1474
1475                 signal(SIGTERM, SIG_DFL);
1476
1477                 close(child_ready_pipe[0]);
1478                 close(go_pipe[1]);
1479                 fcntl(go_pipe[0], F_SETFD, FD_CLOEXEC);
1480
1481                 /*
1482                  * Tell the parent we're ready to go
1483                  */
1484                 close(child_ready_pipe[1]);
1485
1486                 /*
1487                  * Wait until the parent tells us to go.
1488                  */
1489                 ret = read(go_pipe[0], &bf, 1);
1490                 /*
1491                  * The parent will ask for the execvp() to be performed by
1492                  * writing exactly one byte, in workload.cork_fd, usually via
1493                  * perf_evlist__start_workload().
1494                  *
1495                  * For cancelling the workload without actually running it,
1496                  * the parent will just close workload.cork_fd, without writing
1497                  * anything, i.e. read will return zero and we just exit()
1498                  * here.
1499                  */
1500                 if (ret != 1) {
1501                         if (ret == -1)
1502                                 perror("unable to read pipe");
1503                         exit(ret);
1504                 }
1505
1506                 execvp(argv[0], (char **)argv);
1507
1508                 if (exec_error) {
1509                         union sigval val;
1510
1511                         val.sival_int = errno;
1512                         if (sigqueue(getppid(), SIGUSR1, val))
1513                                 perror(argv[0]);
1514                 } else
1515                         perror(argv[0]);
1516                 exit(-1);
1517         }
1518
1519         if (exec_error) {
1520                 struct sigaction act = {
1521                         .sa_flags     = SA_SIGINFO,
1522                         .sa_sigaction = exec_error,
1523                 };
1524                 sigaction(SIGUSR1, &act, NULL);
1525         }
1526
1527         if (target__none(target)) {
1528                 if (evlist->threads == NULL) {
1529                         fprintf(stderr, "FATAL: evlist->threads need to be set at this point (%s:%d).\n",
1530                                 __func__, __LINE__);
1531                         goto out_close_pipes;
1532                 }
1533                 thread_map__set_pid(evlist->threads, 0, evlist->workload.pid);
1534         }
1535
1536         close(child_ready_pipe[1]);
1537         close(go_pipe[0]);
1538         /*
1539          * wait for child to settle
1540          */
1541         if (read(child_ready_pipe[0], &bf, 1) == -1) {
1542                 perror("unable to read pipe");
1543                 goto out_close_pipes;
1544         }
1545
1546         fcntl(go_pipe[1], F_SETFD, FD_CLOEXEC);
1547         evlist->workload.cork_fd = go_pipe[1];
1548         close(child_ready_pipe[0]);
1549         return 0;
1550
1551 out_close_pipes:
1552         close(go_pipe[0]);
1553         close(go_pipe[1]);
1554 out_close_ready_pipe:
1555         close(child_ready_pipe[0]);
1556         close(child_ready_pipe[1]);
1557         return -1;
1558 }
1559
1560 int perf_evlist__start_workload(struct perf_evlist *evlist)
1561 {
1562         if (evlist->workload.cork_fd > 0) {
1563                 char bf = 0;
1564                 int ret;
1565                 /*
1566                  * Remove the cork, let it rip!
1567                  */
1568                 ret = write(evlist->workload.cork_fd, &bf, 1);
1569                 if (ret < 0)
1570                         perror("unable to write to pipe");
1571
1572                 close(evlist->workload.cork_fd);
1573                 return ret;
1574         }
1575
1576         return 0;
1577 }
1578
1579 int perf_evlist__parse_sample(struct perf_evlist *evlist, union perf_event *event,
1580                               struct perf_sample *sample)
1581 {
1582         struct perf_evsel *evsel = perf_evlist__event2evsel(evlist, event);
1583
1584         if (!evsel)
1585                 return -EFAULT;
1586         return perf_evsel__parse_sample(evsel, event, sample);
1587 }
1588
1589 int perf_evlist__parse_sample_timestamp(struct perf_evlist *evlist,
1590                                         union perf_event *event,
1591                                         u64 *timestamp)
1592 {
1593         struct perf_evsel *evsel = perf_evlist__event2evsel(evlist, event);
1594
1595         if (!evsel)
1596                 return -EFAULT;
1597         return perf_evsel__parse_sample_timestamp(evsel, event, timestamp);
1598 }
1599
1600 size_t perf_evlist__fprintf(struct perf_evlist *evlist, FILE *fp)
1601 {
1602         struct perf_evsel *evsel;
1603         size_t printed = 0;
1604
1605         evlist__for_each_entry(evlist, evsel) {
1606                 printed += fprintf(fp, "%s%s", evsel->idx ? ", " : "",
1607                                    perf_evsel__name(evsel));
1608         }
1609
1610         return printed + fprintf(fp, "\n");
1611 }
1612
1613 int perf_evlist__strerror_open(struct perf_evlist *evlist,
1614                                int err, char *buf, size_t size)
1615 {
1616         int printed, value;
1617         char sbuf[STRERR_BUFSIZE], *emsg = str_error_r(err, sbuf, sizeof(sbuf));
1618
1619         switch (err) {
1620         case EACCES:
1621         case EPERM:
1622                 printed = scnprintf(buf, size,
1623                                     "Error:\t%s.\n"
1624                                     "Hint:\tCheck /proc/sys/kernel/perf_event_paranoid setting.", emsg);
1625
1626                 value = perf_event_paranoid();
1627
1628                 printed += scnprintf(buf + printed, size - printed, "\nHint:\t");
1629
1630                 if (value >= 2) {
1631                         printed += scnprintf(buf + printed, size - printed,
1632                                              "For your workloads it needs to be <= 1\nHint:\t");
1633                 }
1634                 printed += scnprintf(buf + printed, size - printed,
1635                                      "For system wide tracing it needs to be set to -1.\n");
1636
1637                 printed += scnprintf(buf + printed, size - printed,
1638                                     "Hint:\tTry: 'sudo sh -c \"echo -1 > /proc/sys/kernel/perf_event_paranoid\"'\n"
1639                                     "Hint:\tThe current value is %d.", value);
1640                 break;
1641         case EINVAL: {
1642                 struct perf_evsel *first = perf_evlist__first(evlist);
1643                 int max_freq;
1644
1645                 if (sysctl__read_int("kernel/perf_event_max_sample_rate", &max_freq) < 0)
1646                         goto out_default;
1647
1648                 if (first->attr.sample_freq < (u64)max_freq)
1649                         goto out_default;
1650
1651                 printed = scnprintf(buf, size,
1652                                     "Error:\t%s.\n"
1653                                     "Hint:\tCheck /proc/sys/kernel/perf_event_max_sample_rate.\n"
1654                                     "Hint:\tThe current value is %d and %" PRIu64 " is being requested.",
1655                                     emsg, max_freq, first->attr.sample_freq);
1656                 break;
1657         }
1658         default:
1659 out_default:
1660                 scnprintf(buf, size, "%s", emsg);
1661                 break;
1662         }
1663
1664         return 0;
1665 }
1666
1667 int perf_evlist__strerror_mmap(struct perf_evlist *evlist, int err, char *buf, size_t size)
1668 {
1669         char sbuf[STRERR_BUFSIZE], *emsg = str_error_r(err, sbuf, sizeof(sbuf));
1670         int pages_attempted = evlist->mmap_len / 1024, pages_max_per_user, printed = 0;
1671
1672         switch (err) {
1673         case EPERM:
1674                 sysctl__read_int("kernel/perf_event_mlock_kb", &pages_max_per_user);
1675                 printed += scnprintf(buf + printed, size - printed,
1676                                      "Error:\t%s.\n"
1677                                      "Hint:\tCheck /proc/sys/kernel/perf_event_mlock_kb (%d kB) setting.\n"
1678                                      "Hint:\tTried using %zd kB.\n",
1679                                      emsg, pages_max_per_user, pages_attempted);
1680
1681                 if (pages_attempted >= pages_max_per_user) {
1682                         printed += scnprintf(buf + printed, size - printed,
1683                                              "Hint:\tTry 'sudo sh -c \"echo %d > /proc/sys/kernel/perf_event_mlock_kb\"', or\n",
1684                                              pages_max_per_user + pages_attempted);
1685                 }
1686
1687                 printed += scnprintf(buf + printed, size - printed,
1688                                      "Hint:\tTry using a smaller -m/--mmap-pages value.");
1689                 break;
1690         default:
1691                 scnprintf(buf, size, "%s", emsg);
1692                 break;
1693         }
1694
1695         return 0;
1696 }
1697
1698 void perf_evlist__to_front(struct perf_evlist *evlist,
1699                            struct perf_evsel *move_evsel)
1700 {
1701         struct perf_evsel *evsel, *n;
1702         LIST_HEAD(move);
1703
1704         if (move_evsel == perf_evlist__first(evlist))
1705                 return;
1706
1707         evlist__for_each_entry_safe(evlist, n, evsel) {
1708                 if (evsel->leader == move_evsel->leader)
1709                         list_move_tail(&evsel->node, &move);
1710         }
1711
1712         list_splice(&move, &evlist->entries);
1713 }
1714
1715 void perf_evlist__set_tracking_event(struct perf_evlist *evlist,
1716                                      struct perf_evsel *tracking_evsel)
1717 {
1718         struct perf_evsel *evsel;
1719
1720         if (tracking_evsel->tracking)
1721                 return;
1722
1723         evlist__for_each_entry(evlist, evsel) {
1724                 if (evsel != tracking_evsel)
1725                         evsel->tracking = false;
1726         }
1727
1728         tracking_evsel->tracking = true;
1729 }
1730
1731 struct perf_evsel *
1732 perf_evlist__find_evsel_by_str(struct perf_evlist *evlist,
1733                                const char *str)
1734 {
1735         struct perf_evsel *evsel;
1736
1737         evlist__for_each_entry(evlist, evsel) {
1738                 if (!evsel->name)
1739                         continue;
1740                 if (strcmp(str, evsel->name) == 0)
1741                         return evsel;
1742         }
1743
1744         return NULL;
1745 }
1746
1747 void perf_evlist__toggle_bkw_mmap(struct perf_evlist *evlist,
1748                                   enum bkw_mmap_state state)
1749 {
1750         enum bkw_mmap_state old_state = evlist->bkw_mmap_state;
1751         enum action {
1752                 NONE,
1753                 PAUSE,
1754                 RESUME,
1755         } action = NONE;
1756
1757         if (!evlist->overwrite_mmap)
1758                 return;
1759
1760         switch (old_state) {
1761         case BKW_MMAP_NOTREADY: {
1762                 if (state != BKW_MMAP_RUNNING)
1763                         goto state_err;;
1764                 break;
1765         }
1766         case BKW_MMAP_RUNNING: {
1767                 if (state != BKW_MMAP_DATA_PENDING)
1768                         goto state_err;
1769                 action = PAUSE;
1770                 break;
1771         }
1772         case BKW_MMAP_DATA_PENDING: {
1773                 if (state != BKW_MMAP_EMPTY)
1774                         goto state_err;
1775                 break;
1776         }
1777         case BKW_MMAP_EMPTY: {
1778                 if (state != BKW_MMAP_RUNNING)
1779                         goto state_err;
1780                 action = RESUME;
1781                 break;
1782         }
1783         default:
1784                 WARN_ONCE(1, "Shouldn't get there\n");
1785         }
1786
1787         evlist->bkw_mmap_state = state;
1788
1789         switch (action) {
1790         case PAUSE:
1791                 perf_evlist__pause(evlist);
1792                 break;
1793         case RESUME:
1794                 perf_evlist__resume(evlist);
1795                 break;
1796         case NONE:
1797         default:
1798                 break;
1799         }
1800
1801 state_err:
1802         return;
1803 }
1804
1805 bool perf_evlist__exclude_kernel(struct perf_evlist *evlist)
1806 {
1807         struct perf_evsel *evsel;
1808
1809         evlist__for_each_entry(evlist, evsel) {
1810                 if (!evsel->attr.exclude_kernel)
1811                         return false;
1812         }
1813
1814         return true;
1815 }