7d71a691b8641306fb012311e09de9c74b46e896
[linux-3.10.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 <lk/debugfs.h>
11 #include <poll.h>
12 #include "cpumap.h"
13 #include "thread_map.h"
14 #include "target.h"
15 #include "evlist.h"
16 #include "evsel.h"
17 #include <unistd.h>
18
19 #include "parse-events.h"
20
21 #include <sys/mman.h>
22
23 #include <linux/bitops.h>
24 #include <linux/hash.h>
25
26 #define FD(e, x, y) (*(int *)xyarray__entry(e->fd, x, y))
27 #define SID(e, x, y) xyarray__entry(e->sample_id, x, y)
28
29 void perf_evlist__init(struct perf_evlist *evlist, struct cpu_map *cpus,
30                        struct thread_map *threads)
31 {
32         int i;
33
34         for (i = 0; i < PERF_EVLIST__HLIST_SIZE; ++i)
35                 INIT_HLIST_HEAD(&evlist->heads[i]);
36         INIT_LIST_HEAD(&evlist->entries);
37         perf_evlist__set_maps(evlist, cpus, threads);
38         evlist->workload.pid = -1;
39 }
40
41 struct perf_evlist *perf_evlist__new(void)
42 {
43         struct perf_evlist *evlist = zalloc(sizeof(*evlist));
44
45         if (evlist != NULL)
46                 perf_evlist__init(evlist, NULL, NULL);
47
48         return evlist;
49 }
50
51 void perf_evlist__config(struct perf_evlist *evlist,
52                         struct perf_record_opts *opts)
53 {
54         struct perf_evsel *evsel;
55         /*
56          * Set the evsel leader links before we configure attributes,
57          * since some might depend on this info.
58          */
59         if (opts->group)
60                 perf_evlist__set_leader(evlist);
61
62         if (evlist->cpus->map[0] < 0)
63                 opts->no_inherit = true;
64
65         list_for_each_entry(evsel, &evlist->entries, node) {
66                 perf_evsel__config(evsel, opts);
67
68                 if (evlist->nr_entries > 1)
69                         perf_evsel__set_sample_id(evsel);
70         }
71 }
72
73 static void perf_evlist__purge(struct perf_evlist *evlist)
74 {
75         struct perf_evsel *pos, *n;
76
77         list_for_each_entry_safe(pos, n, &evlist->entries, node) {
78                 list_del_init(&pos->node);
79                 perf_evsel__delete(pos);
80         }
81
82         evlist->nr_entries = 0;
83 }
84
85 void perf_evlist__exit(struct perf_evlist *evlist)
86 {
87         free(evlist->mmap);
88         free(evlist->pollfd);
89         evlist->mmap = NULL;
90         evlist->pollfd = NULL;
91 }
92
93 void perf_evlist__delete(struct perf_evlist *evlist)
94 {
95         perf_evlist__purge(evlist);
96         perf_evlist__exit(evlist);
97         free(evlist);
98 }
99
100 void perf_evlist__add(struct perf_evlist *evlist, struct perf_evsel *entry)
101 {
102         list_add_tail(&entry->node, &evlist->entries);
103         ++evlist->nr_entries;
104 }
105
106 void perf_evlist__splice_list_tail(struct perf_evlist *evlist,
107                                    struct list_head *list,
108                                    int nr_entries)
109 {
110         list_splice_tail(list, &evlist->entries);
111         evlist->nr_entries += nr_entries;
112 }
113
114 void __perf_evlist__set_leader(struct list_head *list)
115 {
116         struct perf_evsel *evsel, *leader;
117
118         leader = list_entry(list->next, struct perf_evsel, node);
119         evsel = list_entry(list->prev, struct perf_evsel, node);
120
121         leader->nr_members = evsel->idx - leader->idx + 1;
122
123         list_for_each_entry(evsel, list, node) {
124                 evsel->leader = leader;
125         }
126 }
127
128 void perf_evlist__set_leader(struct perf_evlist *evlist)
129 {
130         if (evlist->nr_entries) {
131                 evlist->nr_groups = evlist->nr_entries > 1 ? 1 : 0;
132                 __perf_evlist__set_leader(&evlist->entries);
133         }
134 }
135
136 int perf_evlist__add_default(struct perf_evlist *evlist)
137 {
138         struct perf_event_attr attr = {
139                 .type = PERF_TYPE_HARDWARE,
140                 .config = PERF_COUNT_HW_CPU_CYCLES,
141         };
142         struct perf_evsel *evsel;
143
144         event_attr_init(&attr);
145
146         evsel = perf_evsel__new(&attr, 0);
147         if (evsel == NULL)
148                 goto error;
149
150         /* use strdup() because free(evsel) assumes name is allocated */
151         evsel->name = strdup("cycles");
152         if (!evsel->name)
153                 goto error_free;
154
155         perf_evlist__add(evlist, evsel);
156         return 0;
157 error_free:
158         perf_evsel__delete(evsel);
159 error:
160         return -ENOMEM;
161 }
162
163 static int perf_evlist__add_attrs(struct perf_evlist *evlist,
164                                   struct perf_event_attr *attrs, size_t nr_attrs)
165 {
166         struct perf_evsel *evsel, *n;
167         LIST_HEAD(head);
168         size_t i;
169
170         for (i = 0; i < nr_attrs; i++) {
171                 evsel = perf_evsel__new(attrs + i, evlist->nr_entries + i);
172                 if (evsel == NULL)
173                         goto out_delete_partial_list;
174                 list_add_tail(&evsel->node, &head);
175         }
176
177         perf_evlist__splice_list_tail(evlist, &head, nr_attrs);
178
179         return 0;
180
181 out_delete_partial_list:
182         list_for_each_entry_safe(evsel, n, &head, node)
183                 perf_evsel__delete(evsel);
184         return -1;
185 }
186
187 int __perf_evlist__add_default_attrs(struct perf_evlist *evlist,
188                                      struct perf_event_attr *attrs, size_t nr_attrs)
189 {
190         size_t i;
191
192         for (i = 0; i < nr_attrs; i++)
193                 event_attr_init(attrs + i);
194
195         return perf_evlist__add_attrs(evlist, attrs, nr_attrs);
196 }
197
198 struct perf_evsel *
199 perf_evlist__find_tracepoint_by_id(struct perf_evlist *evlist, int id)
200 {
201         struct perf_evsel *evsel;
202
203         list_for_each_entry(evsel, &evlist->entries, node) {
204                 if (evsel->attr.type   == PERF_TYPE_TRACEPOINT &&
205                     (int)evsel->attr.config == id)
206                         return evsel;
207         }
208
209         return NULL;
210 }
211
212 int perf_evlist__add_newtp(struct perf_evlist *evlist,
213                            const char *sys, const char *name, void *handler)
214 {
215         struct perf_evsel *evsel;
216
217         evsel = perf_evsel__newtp(sys, name, evlist->nr_entries);
218         if (evsel == NULL)
219                 return -1;
220
221         evsel->handler.func = handler;
222         perf_evlist__add(evlist, evsel);
223         return 0;
224 }
225
226 void perf_evlist__disable(struct perf_evlist *evlist)
227 {
228         int cpu, thread;
229         struct perf_evsel *pos;
230         int nr_cpus = cpu_map__nr(evlist->cpus);
231         int nr_threads = thread_map__nr(evlist->threads);
232
233         for (cpu = 0; cpu < nr_cpus; cpu++) {
234                 list_for_each_entry(pos, &evlist->entries, node) {
235                         if (!perf_evsel__is_group_leader(pos))
236                                 continue;
237                         for (thread = 0; thread < nr_threads; thread++)
238                                 ioctl(FD(pos, cpu, thread),
239                                       PERF_EVENT_IOC_DISABLE, 0);
240                 }
241         }
242 }
243
244 void perf_evlist__enable(struct perf_evlist *evlist)
245 {
246         int cpu, thread;
247         struct perf_evsel *pos;
248         int nr_cpus = cpu_map__nr(evlist->cpus);
249         int nr_threads = thread_map__nr(evlist->threads);
250
251         for (cpu = 0; cpu < nr_cpus; cpu++) {
252                 list_for_each_entry(pos, &evlist->entries, node) {
253                         if (!perf_evsel__is_group_leader(pos))
254                                 continue;
255                         for (thread = 0; thread < nr_threads; thread++)
256                                 ioctl(FD(pos, cpu, thread),
257                                       PERF_EVENT_IOC_ENABLE, 0);
258                 }
259         }
260 }
261
262 static int perf_evlist__alloc_pollfd(struct perf_evlist *evlist)
263 {
264         int nr_cpus = cpu_map__nr(evlist->cpus);
265         int nr_threads = thread_map__nr(evlist->threads);
266         int nfds = nr_cpus * nr_threads * evlist->nr_entries;
267         evlist->pollfd = malloc(sizeof(struct pollfd) * nfds);
268         return evlist->pollfd != NULL ? 0 : -ENOMEM;
269 }
270
271 void perf_evlist__add_pollfd(struct perf_evlist *evlist, int fd)
272 {
273         fcntl(fd, F_SETFL, O_NONBLOCK);
274         evlist->pollfd[evlist->nr_fds].fd = fd;
275         evlist->pollfd[evlist->nr_fds].events = POLLIN;
276         evlist->nr_fds++;
277 }
278
279 static void perf_evlist__id_hash(struct perf_evlist *evlist,
280                                  struct perf_evsel *evsel,
281                                  int cpu, int thread, u64 id)
282 {
283         int hash;
284         struct perf_sample_id *sid = SID(evsel, cpu, thread);
285
286         sid->id = id;
287         sid->evsel = evsel;
288         hash = hash_64(sid->id, PERF_EVLIST__HLIST_BITS);
289         hlist_add_head(&sid->node, &evlist->heads[hash]);
290 }
291
292 void perf_evlist__id_add(struct perf_evlist *evlist, struct perf_evsel *evsel,
293                          int cpu, int thread, u64 id)
294 {
295         perf_evlist__id_hash(evlist, evsel, cpu, thread, id);
296         evsel->id[evsel->ids++] = id;
297 }
298
299 static int perf_evlist__id_add_fd(struct perf_evlist *evlist,
300                                   struct perf_evsel *evsel,
301                                   int cpu, int thread, int fd)
302 {
303         u64 read_data[4] = { 0, };
304         int id_idx = 1; /* The first entry is the counter value */
305
306         if (!(evsel->attr.read_format & PERF_FORMAT_ID) ||
307             read(fd, &read_data, sizeof(read_data)) == -1)
308                 return -1;
309
310         if (evsel->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
311                 ++id_idx;
312         if (evsel->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
313                 ++id_idx;
314
315         perf_evlist__id_add(evlist, evsel, cpu, thread, read_data[id_idx]);
316         return 0;
317 }
318
319 struct perf_evsel *perf_evlist__id2evsel(struct perf_evlist *evlist, u64 id)
320 {
321         struct hlist_head *head;
322         struct hlist_node *pos;
323         struct perf_sample_id *sid;
324         int hash;
325
326         if (evlist->nr_entries == 1)
327                 return perf_evlist__first(evlist);
328
329         hash = hash_64(id, PERF_EVLIST__HLIST_BITS);
330         head = &evlist->heads[hash];
331
332         hlist_for_each_entry(sid, pos, head, node)
333                 if (sid->id == id)
334                         return sid->evsel;
335
336         if (!perf_evlist__sample_id_all(evlist))
337                 return perf_evlist__first(evlist);
338
339         return NULL;
340 }
341
342 union perf_event *perf_evlist__mmap_read(struct perf_evlist *evlist, int idx)
343 {
344         struct perf_mmap *md = &evlist->mmap[idx];
345         unsigned int head = perf_mmap__read_head(md);
346         unsigned int old = md->prev;
347         unsigned char *data = md->base + page_size;
348         union perf_event *event = NULL;
349
350         if (evlist->overwrite) {
351                 /*
352                  * If we're further behind than half the buffer, there's a chance
353                  * the writer will bite our tail and mess up the samples under us.
354                  *
355                  * If we somehow ended up ahead of the head, we got messed up.
356                  *
357                  * In either case, truncate and restart at head.
358                  */
359                 int diff = head - old;
360                 if (diff > md->mask / 2 || diff < 0) {
361                         fprintf(stderr, "WARNING: failed to keep up with mmap data.\n");
362
363                         /*
364                          * head points to a known good entry, start there.
365                          */
366                         old = head;
367                 }
368         }
369
370         if (old != head) {
371                 size_t size;
372
373                 event = (union perf_event *)&data[old & md->mask];
374                 size = event->header.size;
375
376                 /*
377                  * Event straddles the mmap boundary -- header should always
378                  * be inside due to u64 alignment of output.
379                  */
380                 if ((old & md->mask) + size != ((old + size) & md->mask)) {
381                         unsigned int offset = old;
382                         unsigned int len = min(sizeof(*event), size), cpy;
383                         void *dst = &md->event_copy;
384
385                         do {
386                                 cpy = min(md->mask + 1 - (offset & md->mask), len);
387                                 memcpy(dst, &data[offset & md->mask], cpy);
388                                 offset += cpy;
389                                 dst += cpy;
390                                 len -= cpy;
391                         } while (len);
392
393                         event = &md->event_copy;
394                 }
395
396                 old += size;
397         }
398
399         md->prev = old;
400
401         if (!evlist->overwrite)
402                 perf_mmap__write_tail(md, old);
403
404         return event;
405 }
406
407 void perf_evlist__munmap(struct perf_evlist *evlist)
408 {
409         int i;
410
411         for (i = 0; i < evlist->nr_mmaps; i++) {
412                 if (evlist->mmap[i].base != NULL) {
413                         munmap(evlist->mmap[i].base, evlist->mmap_len);
414                         evlist->mmap[i].base = NULL;
415                 }
416         }
417
418         free(evlist->mmap);
419         evlist->mmap = NULL;
420 }
421
422 static int perf_evlist__alloc_mmap(struct perf_evlist *evlist)
423 {
424         evlist->nr_mmaps = cpu_map__nr(evlist->cpus);
425         if (cpu_map__all(evlist->cpus))
426                 evlist->nr_mmaps = thread_map__nr(evlist->threads);
427         evlist->mmap = zalloc(evlist->nr_mmaps * sizeof(struct perf_mmap));
428         return evlist->mmap != NULL ? 0 : -ENOMEM;
429 }
430
431 static int __perf_evlist__mmap(struct perf_evlist *evlist,
432                                int idx, int prot, int mask, int fd)
433 {
434         evlist->mmap[idx].prev = 0;
435         evlist->mmap[idx].mask = mask;
436         evlist->mmap[idx].base = mmap(NULL, evlist->mmap_len, prot,
437                                       MAP_SHARED, fd, 0);
438         if (evlist->mmap[idx].base == MAP_FAILED) {
439                 evlist->mmap[idx].base = NULL;
440                 return -1;
441         }
442
443         perf_evlist__add_pollfd(evlist, fd);
444         return 0;
445 }
446
447 static int perf_evlist__mmap_per_cpu(struct perf_evlist *evlist, int prot, int mask)
448 {
449         struct perf_evsel *evsel;
450         int cpu, thread;
451         int nr_cpus = cpu_map__nr(evlist->cpus);
452         int nr_threads = thread_map__nr(evlist->threads);
453
454         for (cpu = 0; cpu < nr_cpus; cpu++) {
455                 int output = -1;
456
457                 for (thread = 0; thread < nr_threads; thread++) {
458                         list_for_each_entry(evsel, &evlist->entries, node) {
459                                 int fd = FD(evsel, cpu, thread);
460
461                                 if (output == -1) {
462                                         output = fd;
463                                         if (__perf_evlist__mmap(evlist, cpu,
464                                                                 prot, mask, output) < 0)
465                                                 goto out_unmap;
466                                 } else {
467                                         if (ioctl(fd, PERF_EVENT_IOC_SET_OUTPUT, output) != 0)
468                                                 goto out_unmap;
469                                 }
470
471                                 if ((evsel->attr.read_format & PERF_FORMAT_ID) &&
472                                     perf_evlist__id_add_fd(evlist, evsel, cpu, thread, fd) < 0)
473                                         goto out_unmap;
474                         }
475                 }
476         }
477
478         return 0;
479
480 out_unmap:
481         for (cpu = 0; cpu < nr_cpus; cpu++) {
482                 if (evlist->mmap[cpu].base != NULL) {
483                         munmap(evlist->mmap[cpu].base, evlist->mmap_len);
484                         evlist->mmap[cpu].base = NULL;
485                 }
486         }
487         return -1;
488 }
489
490 static int perf_evlist__mmap_per_thread(struct perf_evlist *evlist, int prot, int mask)
491 {
492         struct perf_evsel *evsel;
493         int thread;
494         int nr_threads = thread_map__nr(evlist->threads);
495
496         for (thread = 0; thread < nr_threads; thread++) {
497                 int output = -1;
498
499                 list_for_each_entry(evsel, &evlist->entries, node) {
500                         int fd = FD(evsel, 0, thread);
501
502                         if (output == -1) {
503                                 output = fd;
504                                 if (__perf_evlist__mmap(evlist, thread,
505                                                         prot, mask, output) < 0)
506                                         goto out_unmap;
507                         } else {
508                                 if (ioctl(fd, PERF_EVENT_IOC_SET_OUTPUT, output) != 0)
509                                         goto out_unmap;
510                         }
511
512                         if ((evsel->attr.read_format & PERF_FORMAT_ID) &&
513                             perf_evlist__id_add_fd(evlist, evsel, 0, thread, fd) < 0)
514                                 goto out_unmap;
515                 }
516         }
517
518         return 0;
519
520 out_unmap:
521         for (thread = 0; thread < nr_threads; thread++) {
522                 if (evlist->mmap[thread].base != NULL) {
523                         munmap(evlist->mmap[thread].base, evlist->mmap_len);
524                         evlist->mmap[thread].base = NULL;
525                 }
526         }
527         return -1;
528 }
529
530 /** perf_evlist__mmap - Create per cpu maps to receive events
531  *
532  * @evlist - list of events
533  * @pages - map length in pages
534  * @overwrite - overwrite older events?
535  *
536  * If overwrite is false the user needs to signal event consuption using:
537  *
538  *      struct perf_mmap *m = &evlist->mmap[cpu];
539  *      unsigned int head = perf_mmap__read_head(m);
540  *
541  *      perf_mmap__write_tail(m, head)
542  *
543  * Using perf_evlist__read_on_cpu does this automatically.
544  */
545 int perf_evlist__mmap(struct perf_evlist *evlist, unsigned int pages,
546                       bool overwrite)
547 {
548         struct perf_evsel *evsel;
549         const struct cpu_map *cpus = evlist->cpus;
550         const struct thread_map *threads = evlist->threads;
551         int prot = PROT_READ | (overwrite ? 0 : PROT_WRITE), mask;
552
553         /* 512 kiB: default amount of unprivileged mlocked memory */
554         if (pages == UINT_MAX)
555                 pages = (512 * 1024) / page_size;
556         else if (!is_power_of_2(pages))
557                 return -EINVAL;
558
559         mask = pages * page_size - 1;
560
561         if (evlist->mmap == NULL && perf_evlist__alloc_mmap(evlist) < 0)
562                 return -ENOMEM;
563
564         if (evlist->pollfd == NULL && perf_evlist__alloc_pollfd(evlist) < 0)
565                 return -ENOMEM;
566
567         evlist->overwrite = overwrite;
568         evlist->mmap_len = (pages + 1) * page_size;
569
570         list_for_each_entry(evsel, &evlist->entries, node) {
571                 if ((evsel->attr.read_format & PERF_FORMAT_ID) &&
572                     evsel->sample_id == NULL &&
573                     perf_evsel__alloc_id(evsel, cpu_map__nr(cpus), threads->nr) < 0)
574                         return -ENOMEM;
575         }
576
577         if (cpu_map__all(cpus))
578                 return perf_evlist__mmap_per_thread(evlist, prot, mask);
579
580         return perf_evlist__mmap_per_cpu(evlist, prot, mask);
581 }
582
583 int perf_evlist__create_maps(struct perf_evlist *evlist,
584                              struct perf_target *target)
585 {
586         evlist->threads = thread_map__new_str(target->pid, target->tid,
587                                               target->uid);
588
589         if (evlist->threads == NULL)
590                 return -1;
591
592         if (perf_target__has_task(target))
593                 evlist->cpus = cpu_map__dummy_new();
594         else if (!perf_target__has_cpu(target) && !target->uses_mmap)
595                 evlist->cpus = cpu_map__dummy_new();
596         else
597                 evlist->cpus = cpu_map__new(target->cpu_list);
598
599         if (evlist->cpus == NULL)
600                 goto out_delete_threads;
601
602         return 0;
603
604 out_delete_threads:
605         thread_map__delete(evlist->threads);
606         return -1;
607 }
608
609 void perf_evlist__delete_maps(struct perf_evlist *evlist)
610 {
611         cpu_map__delete(evlist->cpus);
612         thread_map__delete(evlist->threads);
613         evlist->cpus    = NULL;
614         evlist->threads = NULL;
615 }
616
617 int perf_evlist__apply_filters(struct perf_evlist *evlist)
618 {
619         struct perf_evsel *evsel;
620         int err = 0;
621         const int ncpus = cpu_map__nr(evlist->cpus),
622                   nthreads = thread_map__nr(evlist->threads);
623
624         list_for_each_entry(evsel, &evlist->entries, node) {
625                 if (evsel->filter == NULL)
626                         continue;
627
628                 err = perf_evsel__set_filter(evsel, ncpus, nthreads, evsel->filter);
629                 if (err)
630                         break;
631         }
632
633         return err;
634 }
635
636 int perf_evlist__set_filter(struct perf_evlist *evlist, const char *filter)
637 {
638         struct perf_evsel *evsel;
639         int err = 0;
640         const int ncpus = cpu_map__nr(evlist->cpus),
641                   nthreads = thread_map__nr(evlist->threads);
642
643         list_for_each_entry(evsel, &evlist->entries, node) {
644                 err = perf_evsel__set_filter(evsel, ncpus, nthreads, filter);
645                 if (err)
646                         break;
647         }
648
649         return err;
650 }
651
652 bool perf_evlist__valid_sample_type(struct perf_evlist *evlist)
653 {
654         struct perf_evsel *first = perf_evlist__first(evlist), *pos = first;
655
656         list_for_each_entry_continue(pos, &evlist->entries, node) {
657                 if (first->attr.sample_type != pos->attr.sample_type)
658                         return false;
659         }
660
661         return true;
662 }
663
664 u64 perf_evlist__sample_type(struct perf_evlist *evlist)
665 {
666         struct perf_evsel *first = perf_evlist__first(evlist);
667         return first->attr.sample_type;
668 }
669
670 u16 perf_evlist__id_hdr_size(struct perf_evlist *evlist)
671 {
672         struct perf_evsel *first = perf_evlist__first(evlist);
673         struct perf_sample *data;
674         u64 sample_type;
675         u16 size = 0;
676
677         if (!first->attr.sample_id_all)
678                 goto out;
679
680         sample_type = first->attr.sample_type;
681
682         if (sample_type & PERF_SAMPLE_TID)
683                 size += sizeof(data->tid) * 2;
684
685        if (sample_type & PERF_SAMPLE_TIME)
686                 size += sizeof(data->time);
687
688         if (sample_type & PERF_SAMPLE_ID)
689                 size += sizeof(data->id);
690
691         if (sample_type & PERF_SAMPLE_STREAM_ID)
692                 size += sizeof(data->stream_id);
693
694         if (sample_type & PERF_SAMPLE_CPU)
695                 size += sizeof(data->cpu) * 2;
696 out:
697         return size;
698 }
699
700 bool perf_evlist__valid_sample_id_all(struct perf_evlist *evlist)
701 {
702         struct perf_evsel *first = perf_evlist__first(evlist), *pos = first;
703
704         list_for_each_entry_continue(pos, &evlist->entries, node) {
705                 if (first->attr.sample_id_all != pos->attr.sample_id_all)
706                         return false;
707         }
708
709         return true;
710 }
711
712 bool perf_evlist__sample_id_all(struct perf_evlist *evlist)
713 {
714         struct perf_evsel *first = perf_evlist__first(evlist);
715         return first->attr.sample_id_all;
716 }
717
718 void perf_evlist__set_selected(struct perf_evlist *evlist,
719                                struct perf_evsel *evsel)
720 {
721         evlist->selected = evsel;
722 }
723
724 int perf_evlist__open(struct perf_evlist *evlist)
725 {
726         struct perf_evsel *evsel;
727         int err, ncpus, nthreads;
728
729         list_for_each_entry(evsel, &evlist->entries, node) {
730                 err = perf_evsel__open(evsel, evlist->cpus, evlist->threads);
731                 if (err < 0)
732                         goto out_err;
733         }
734
735         return 0;
736 out_err:
737         ncpus = cpu_map__nr(evlist->cpus);
738         nthreads = thread_map__nr(evlist->threads);
739
740         list_for_each_entry_reverse(evsel, &evlist->entries, node)
741                 perf_evsel__close(evsel, ncpus, nthreads);
742
743         errno = -err;
744         return err;
745 }
746
747 int perf_evlist__prepare_workload(struct perf_evlist *evlist,
748                                   struct perf_record_opts *opts,
749                                   const char *argv[])
750 {
751         int child_ready_pipe[2], go_pipe[2];
752         char bf;
753
754         if (pipe(child_ready_pipe) < 0) {
755                 perror("failed to create 'ready' pipe");
756                 return -1;
757         }
758
759         if (pipe(go_pipe) < 0) {
760                 perror("failed to create 'go' pipe");
761                 goto out_close_ready_pipe;
762         }
763
764         evlist->workload.pid = fork();
765         if (evlist->workload.pid < 0) {
766                 perror("failed to fork");
767                 goto out_close_pipes;
768         }
769
770         if (!evlist->workload.pid) {
771                 if (opts->pipe_output)
772                         dup2(2, 1);
773
774                 close(child_ready_pipe[0]);
775                 close(go_pipe[1]);
776                 fcntl(go_pipe[0], F_SETFD, FD_CLOEXEC);
777
778                 /*
779                  * Do a dummy execvp to get the PLT entry resolved,
780                  * so we avoid the resolver overhead on the real
781                  * execvp call.
782                  */
783                 execvp("", (char **)argv);
784
785                 /*
786                  * Tell the parent we're ready to go
787                  */
788                 close(child_ready_pipe[1]);
789
790                 /*
791                  * Wait until the parent tells us to go.
792                  */
793                 if (read(go_pipe[0], &bf, 1) == -1)
794                         perror("unable to read pipe");
795
796                 execvp(argv[0], (char **)argv);
797
798                 perror(argv[0]);
799                 kill(getppid(), SIGUSR1);
800                 exit(-1);
801         }
802
803         if (perf_target__none(&opts->target))
804                 evlist->threads->map[0] = evlist->workload.pid;
805
806         close(child_ready_pipe[1]);
807         close(go_pipe[0]);
808         /*
809          * wait for child to settle
810          */
811         if (read(child_ready_pipe[0], &bf, 1) == -1) {
812                 perror("unable to read pipe");
813                 goto out_close_pipes;
814         }
815
816         evlist->workload.cork_fd = go_pipe[1];
817         close(child_ready_pipe[0]);
818         return 0;
819
820 out_close_pipes:
821         close(go_pipe[0]);
822         close(go_pipe[1]);
823 out_close_ready_pipe:
824         close(child_ready_pipe[0]);
825         close(child_ready_pipe[1]);
826         return -1;
827 }
828
829 int perf_evlist__start_workload(struct perf_evlist *evlist)
830 {
831         if (evlist->workload.cork_fd > 0) {
832                 /*
833                  * Remove the cork, let it rip!
834                  */
835                 return close(evlist->workload.cork_fd);
836         }
837
838         return 0;
839 }
840
841 int perf_evlist__parse_sample(struct perf_evlist *evlist, union perf_event *event,
842                               struct perf_sample *sample)
843 {
844         struct perf_evsel *evsel = perf_evlist__first(evlist);
845         return perf_evsel__parse_sample(evsel, event, sample);
846 }
847
848 size_t perf_evlist__fprintf(struct perf_evlist *evlist, FILE *fp)
849 {
850         struct perf_evsel *evsel;
851         size_t printed = 0;
852
853         list_for_each_entry(evsel, &evlist->entries, node) {
854                 printed += fprintf(fp, "%s%s", evsel->idx ? ", " : "",
855                                    perf_evsel__name(evsel));
856         }
857
858         return printed + fprintf(fp, "\n");;
859 }