1 // SPDX-License-Identifier: GPL-2.0
2 #include <perf/evlist.h>
3 #include <perf/evsel.h>
4 #include <linux/bitops.h>
5 #include <linux/list.h>
6 #include <linux/hash.h>
7 #include <sys/ioctl.h>
8 #include <internal/evlist.h>
9 #include <internal/evsel.h>
10 #include <internal/xyarray.h>
11 #include <internal/mmap.h>
12 #include <internal/cpumap.h>
13 #include <internal/threadmap.h>
14 #include <internal/lib.h>
15 #include <linux/zalloc.h>
16 #include <stdlib.h>
17 #include <errno.h>
18 #include <unistd.h>
19 #include <fcntl.h>
20 #include <signal.h>
21 #include <poll.h>
22 #include <sys/mman.h>
23 #include <perf/cpumap.h>
24 #include <perf/threadmap.h>
25 #include <api/fd/array.h>
26
perf_evlist__init(struct perf_evlist * evlist)27 void perf_evlist__init(struct perf_evlist *evlist)
28 {
29 int i;
30
31 for (i = 0; i < PERF_EVLIST__HLIST_SIZE; ++i)
32 INIT_HLIST_HEAD(&evlist->heads[i]);
33 INIT_LIST_HEAD(&evlist->entries);
34 evlist->nr_entries = 0;
35 fdarray__init(&evlist->pollfd, 64);
36 }
37
__perf_evlist__propagate_maps(struct perf_evlist * evlist,struct perf_evsel * evsel)38 static void __perf_evlist__propagate_maps(struct perf_evlist *evlist,
39 struct perf_evsel *evsel)
40 {
41 /*
42 * We already have cpus for evsel (via PMU sysfs) so
43 * keep it, if there's no target cpu list defined.
44 */
45 if (!evsel->own_cpus || evlist->has_user_cpus) {
46 perf_cpu_map__put(evsel->cpus);
47 evsel->cpus = perf_cpu_map__get(evlist->cpus);
48 } else if (!evsel->system_wide && perf_cpu_map__empty(evlist->cpus)) {
49 perf_cpu_map__put(evsel->cpus);
50 evsel->cpus = perf_cpu_map__get(evlist->cpus);
51 } else if (evsel->cpus != evsel->own_cpus) {
52 perf_cpu_map__put(evsel->cpus);
53 evsel->cpus = perf_cpu_map__get(evsel->own_cpus);
54 }
55
56 perf_thread_map__put(evsel->threads);
57 evsel->threads = perf_thread_map__get(evlist->threads);
58 evlist->all_cpus = perf_cpu_map__merge(evlist->all_cpus, evsel->cpus);
59 }
60
perf_evlist__propagate_maps(struct perf_evlist * evlist)61 static void perf_evlist__propagate_maps(struct perf_evlist *evlist)
62 {
63 struct perf_evsel *evsel;
64
65 perf_evlist__for_each_evsel(evlist, evsel)
66 __perf_evlist__propagate_maps(evlist, evsel);
67 }
68
perf_evlist__add(struct perf_evlist * evlist,struct perf_evsel * evsel)69 void perf_evlist__add(struct perf_evlist *evlist,
70 struct perf_evsel *evsel)
71 {
72 list_add_tail(&evsel->node, &evlist->entries);
73 evlist->nr_entries += 1;
74 __perf_evlist__propagate_maps(evlist, evsel);
75 }
76
perf_evlist__remove(struct perf_evlist * evlist,struct perf_evsel * evsel)77 void perf_evlist__remove(struct perf_evlist *evlist,
78 struct perf_evsel *evsel)
79 {
80 list_del_init(&evsel->node);
81 evlist->nr_entries -= 1;
82 }
83
perf_evlist__new(void)84 struct perf_evlist *perf_evlist__new(void)
85 {
86 struct perf_evlist *evlist = zalloc(sizeof(*evlist));
87
88 if (evlist != NULL)
89 perf_evlist__init(evlist);
90
91 return evlist;
92 }
93
94 struct perf_evsel *
perf_evlist__next(struct perf_evlist * evlist,struct perf_evsel * prev)95 perf_evlist__next(struct perf_evlist *evlist, struct perf_evsel *prev)
96 {
97 struct perf_evsel *next;
98
99 if (!prev) {
100 next = list_first_entry(&evlist->entries,
101 struct perf_evsel,
102 node);
103 } else {
104 next = list_next_entry(prev, node);
105 }
106
107 /* Empty list is noticed here so don't need checking on entry. */
108 if (&next->node == &evlist->entries)
109 return NULL;
110
111 return next;
112 }
113
perf_evlist__purge(struct perf_evlist * evlist)114 static void perf_evlist__purge(struct perf_evlist *evlist)
115 {
116 struct perf_evsel *pos, *n;
117
118 perf_evlist__for_each_entry_safe(evlist, n, pos) {
119 list_del_init(&pos->node);
120 perf_evsel__delete(pos);
121 }
122
123 evlist->nr_entries = 0;
124 }
125
perf_evlist__exit(struct perf_evlist * evlist)126 void perf_evlist__exit(struct perf_evlist *evlist)
127 {
128 perf_cpu_map__put(evlist->cpus);
129 perf_cpu_map__put(evlist->all_cpus);
130 perf_thread_map__put(evlist->threads);
131 evlist->cpus = NULL;
132 evlist->all_cpus = NULL;
133 evlist->threads = NULL;
134 fdarray__exit(&evlist->pollfd);
135 }
136
perf_evlist__delete(struct perf_evlist * evlist)137 void perf_evlist__delete(struct perf_evlist *evlist)
138 {
139 if (evlist == NULL)
140 return;
141
142 perf_evlist__munmap(evlist);
143 perf_evlist__close(evlist);
144 perf_evlist__purge(evlist);
145 perf_evlist__exit(evlist);
146 free(evlist);
147 }
148
perf_evlist__set_maps(struct perf_evlist * evlist,struct perf_cpu_map * cpus,struct perf_thread_map * threads)149 void perf_evlist__set_maps(struct perf_evlist *evlist,
150 struct perf_cpu_map *cpus,
151 struct perf_thread_map *threads)
152 {
153 /*
154 * Allow for the possibility that one or another of the maps isn't being
155 * changed i.e. don't put it. Note we are assuming the maps that are
156 * being applied are brand new and evlist is taking ownership of the
157 * original reference count of 1. If that is not the case it is up to
158 * the caller to increase the reference count.
159 */
160 if (cpus != evlist->cpus) {
161 perf_cpu_map__put(evlist->cpus);
162 evlist->cpus = perf_cpu_map__get(cpus);
163 }
164
165 if (threads != evlist->threads) {
166 perf_thread_map__put(evlist->threads);
167 evlist->threads = perf_thread_map__get(threads);
168 }
169
170 if (!evlist->all_cpus && cpus)
171 evlist->all_cpus = perf_cpu_map__get(cpus);
172
173 perf_evlist__propagate_maps(evlist);
174 }
175
perf_evlist__open(struct perf_evlist * evlist)176 int perf_evlist__open(struct perf_evlist *evlist)
177 {
178 struct perf_evsel *evsel;
179 int err;
180
181 perf_evlist__for_each_entry(evlist, evsel) {
182 err = perf_evsel__open(evsel, evsel->cpus, evsel->threads);
183 if (err < 0)
184 goto out_err;
185 }
186
187 return 0;
188
189 out_err:
190 perf_evlist__close(evlist);
191 return err;
192 }
193
perf_evlist__close(struct perf_evlist * evlist)194 void perf_evlist__close(struct perf_evlist *evlist)
195 {
196 struct perf_evsel *evsel;
197
198 perf_evlist__for_each_entry_reverse(evlist, evsel)
199 perf_evsel__close(evsel);
200 }
201
perf_evlist__enable(struct perf_evlist * evlist)202 void perf_evlist__enable(struct perf_evlist *evlist)
203 {
204 struct perf_evsel *evsel;
205
206 perf_evlist__for_each_entry(evlist, evsel)
207 perf_evsel__enable(evsel);
208 }
209
perf_evlist__disable(struct perf_evlist * evlist)210 void perf_evlist__disable(struct perf_evlist *evlist)
211 {
212 struct perf_evsel *evsel;
213
214 perf_evlist__for_each_entry(evlist, evsel)
215 perf_evsel__disable(evsel);
216 }
217
perf_evlist__read_format(struct perf_evlist * evlist)218 u64 perf_evlist__read_format(struct perf_evlist *evlist)
219 {
220 struct perf_evsel *first = perf_evlist__first(evlist);
221
222 return first->attr.read_format;
223 }
224
225 #define SID(e, x, y) xyarray__entry(e->sample_id, x, y)
226
perf_evlist__id_hash(struct perf_evlist * evlist,struct perf_evsel * evsel,int cpu,int thread,u64 id)227 static void perf_evlist__id_hash(struct perf_evlist *evlist,
228 struct perf_evsel *evsel,
229 int cpu, int thread, u64 id)
230 {
231 int hash;
232 struct perf_sample_id *sid = SID(evsel, cpu, thread);
233
234 sid->id = id;
235 sid->evsel = evsel;
236 hash = hash_64(sid->id, PERF_EVLIST__HLIST_BITS);
237 hlist_add_head(&sid->node, &evlist->heads[hash]);
238 }
239
perf_evlist__id_add(struct perf_evlist * evlist,struct perf_evsel * evsel,int cpu,int thread,u64 id)240 void perf_evlist__id_add(struct perf_evlist *evlist,
241 struct perf_evsel *evsel,
242 int cpu, int thread, u64 id)
243 {
244 perf_evlist__id_hash(evlist, evsel, cpu, thread, id);
245 evsel->id[evsel->ids++] = id;
246 }
247
perf_evlist__id_add_fd(struct perf_evlist * evlist,struct perf_evsel * evsel,int cpu,int thread,int fd)248 int perf_evlist__id_add_fd(struct perf_evlist *evlist,
249 struct perf_evsel *evsel,
250 int cpu, int thread, int fd)
251 {
252 u64 read_data[4] = { 0, };
253 int id_idx = 1; /* The first entry is the counter value */
254 u64 id;
255 int ret;
256
257 ret = ioctl(fd, PERF_EVENT_IOC_ID, &id);
258 if (!ret)
259 goto add;
260
261 if (errno != ENOTTY)
262 return -1;
263
264 /* Legacy way to get event id.. All hail to old kernels! */
265
266 /*
267 * This way does not work with group format read, so bail
268 * out in that case.
269 */
270 if (perf_evlist__read_format(evlist) & PERF_FORMAT_GROUP)
271 return -1;
272
273 if (!(evsel->attr.read_format & PERF_FORMAT_ID) ||
274 read(fd, &read_data, sizeof(read_data)) == -1)
275 return -1;
276
277 if (evsel->attr.read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
278 ++id_idx;
279 if (evsel->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
280 ++id_idx;
281
282 id = read_data[id_idx];
283
284 add:
285 perf_evlist__id_add(evlist, evsel, cpu, thread, id);
286 return 0;
287 }
288
perf_evlist__alloc_pollfd(struct perf_evlist * evlist)289 int perf_evlist__alloc_pollfd(struct perf_evlist *evlist)
290 {
291 int nr_cpus = perf_cpu_map__nr(evlist->cpus);
292 int nr_threads = perf_thread_map__nr(evlist->threads);
293 int nfds = 0;
294 struct perf_evsel *evsel;
295
296 perf_evlist__for_each_entry(evlist, evsel) {
297 if (evsel->system_wide)
298 nfds += nr_cpus;
299 else
300 nfds += nr_cpus * nr_threads;
301 }
302
303 if (fdarray__available_entries(&evlist->pollfd) < nfds &&
304 fdarray__grow(&evlist->pollfd, nfds) < 0)
305 return -ENOMEM;
306
307 return 0;
308 }
309
perf_evlist__add_pollfd(struct perf_evlist * evlist,int fd,void * ptr,short revent,enum fdarray_flags flags)310 int perf_evlist__add_pollfd(struct perf_evlist *evlist, int fd,
311 void *ptr, short revent, enum fdarray_flags flags)
312 {
313 int pos = fdarray__add(&evlist->pollfd, fd, revent | POLLERR | POLLHUP, flags);
314
315 if (pos >= 0) {
316 evlist->pollfd.priv[pos].ptr = ptr;
317 fcntl(fd, F_SETFL, O_NONBLOCK);
318 }
319
320 return pos;
321 }
322
perf_evlist__munmap_filtered(struct fdarray * fda,int fd,void * arg __maybe_unused)323 static void perf_evlist__munmap_filtered(struct fdarray *fda, int fd,
324 void *arg __maybe_unused)
325 {
326 struct perf_mmap *map = fda->priv[fd].ptr;
327
328 if (map)
329 perf_mmap__put(map);
330 }
331
perf_evlist__filter_pollfd(struct perf_evlist * evlist,short revents_and_mask)332 int perf_evlist__filter_pollfd(struct perf_evlist *evlist, short revents_and_mask)
333 {
334 return fdarray__filter(&evlist->pollfd, revents_and_mask,
335 perf_evlist__munmap_filtered, NULL);
336 }
337
perf_evlist__poll(struct perf_evlist * evlist,int timeout)338 int perf_evlist__poll(struct perf_evlist *evlist, int timeout)
339 {
340 return fdarray__poll(&evlist->pollfd, timeout);
341 }
342
perf_evlist__alloc_mmap(struct perf_evlist * evlist,bool overwrite)343 static struct perf_mmap* perf_evlist__alloc_mmap(struct perf_evlist *evlist, bool overwrite)
344 {
345 int i;
346 struct perf_mmap *map;
347
348 map = zalloc(evlist->nr_mmaps * sizeof(struct perf_mmap));
349 if (!map)
350 return NULL;
351
352 for (i = 0; i < evlist->nr_mmaps; i++) {
353 struct perf_mmap *prev = i ? &map[i - 1] : NULL;
354
355 /*
356 * When the perf_mmap() call is made we grab one refcount, plus
357 * one extra to let perf_mmap__consume() get the last
358 * events after all real references (perf_mmap__get()) are
359 * dropped.
360 *
361 * Each PERF_EVENT_IOC_SET_OUTPUT points to this mmap and
362 * thus does perf_mmap__get() on it.
363 */
364 perf_mmap__init(&map[i], prev, overwrite, NULL);
365 }
366
367 return map;
368 }
369
perf_evsel__set_sid_idx(struct perf_evsel * evsel,int idx,int cpu,int thread)370 static void perf_evsel__set_sid_idx(struct perf_evsel *evsel, int idx, int cpu, int thread)
371 {
372 struct perf_sample_id *sid = SID(evsel, cpu, thread);
373
374 sid->idx = idx;
375 sid->cpu = perf_cpu_map__cpu(evsel->cpus, cpu);
376 sid->tid = perf_thread_map__pid(evsel->threads, thread);
377 }
378
379 static struct perf_mmap*
perf_evlist__mmap_cb_get(struct perf_evlist * evlist,bool overwrite,int idx)380 perf_evlist__mmap_cb_get(struct perf_evlist *evlist, bool overwrite, int idx)
381 {
382 struct perf_mmap *maps;
383
384 maps = overwrite ? evlist->mmap_ovw : evlist->mmap;
385
386 if (!maps) {
387 maps = perf_evlist__alloc_mmap(evlist, overwrite);
388 if (!maps)
389 return NULL;
390
391 if (overwrite)
392 evlist->mmap_ovw = maps;
393 else
394 evlist->mmap = maps;
395 }
396
397 return &maps[idx];
398 }
399
400 #define FD(e, x, y) (*(int *) xyarray__entry(e->fd, x, y))
401
402 static int
perf_evlist__mmap_cb_mmap(struct perf_mmap * map,struct perf_mmap_param * mp,int output,int cpu)403 perf_evlist__mmap_cb_mmap(struct perf_mmap *map, struct perf_mmap_param *mp,
404 int output, int cpu)
405 {
406 return perf_mmap__mmap(map, mp, output, cpu);
407 }
408
perf_evlist__set_mmap_first(struct perf_evlist * evlist,struct perf_mmap * map,bool overwrite)409 static void perf_evlist__set_mmap_first(struct perf_evlist *evlist, struct perf_mmap *map,
410 bool overwrite)
411 {
412 if (overwrite)
413 evlist->mmap_ovw_first = map;
414 else
415 evlist->mmap_first = map;
416 }
417
418 static int
mmap_per_evsel(struct perf_evlist * evlist,struct perf_evlist_mmap_ops * ops,int idx,struct perf_mmap_param * mp,int cpu_idx,int thread,int * _output,int * _output_overwrite)419 mmap_per_evsel(struct perf_evlist *evlist, struct perf_evlist_mmap_ops *ops,
420 int idx, struct perf_mmap_param *mp, int cpu_idx,
421 int thread, int *_output, int *_output_overwrite)
422 {
423 int evlist_cpu = perf_cpu_map__cpu(evlist->cpus, cpu_idx);
424 struct perf_evsel *evsel;
425 int revent;
426
427 perf_evlist__for_each_entry(evlist, evsel) {
428 bool overwrite = evsel->attr.write_backward;
429 struct perf_mmap *map;
430 int *output, fd, cpu;
431
432 if (evsel->system_wide && thread)
433 continue;
434
435 cpu = perf_cpu_map__idx(evsel->cpus, evlist_cpu);
436 if (cpu == -1)
437 continue;
438
439 map = ops->get(evlist, overwrite, idx);
440 if (map == NULL)
441 return -ENOMEM;
442
443 if (overwrite) {
444 mp->prot = PROT_READ;
445 output = _output_overwrite;
446 } else {
447 mp->prot = PROT_READ | PROT_WRITE;
448 output = _output;
449 }
450
451 fd = FD(evsel, cpu, thread);
452
453 if (*output == -1) {
454 *output = fd;
455
456 /*
457 * The last one will be done at perf_mmap__consume(), so that we
458 * make sure we don't prevent tools from consuming every last event in
459 * the ring buffer.
460 *
461 * I.e. we can get the POLLHUP meaning that the fd doesn't exist
462 * anymore, but the last events for it are still in the ring buffer,
463 * waiting to be consumed.
464 *
465 * Tools can chose to ignore this at their own discretion, but the
466 * evlist layer can't just drop it when filtering events in
467 * perf_evlist__filter_pollfd().
468 */
469 refcount_set(&map->refcnt, 2);
470
471 if (ops->mmap(map, mp, *output, evlist_cpu) < 0)
472 return -1;
473
474 if (!idx)
475 perf_evlist__set_mmap_first(evlist, map, overwrite);
476 } else {
477 if (ioctl(fd, PERF_EVENT_IOC_SET_OUTPUT, *output) != 0)
478 return -1;
479
480 perf_mmap__get(map);
481 }
482
483 revent = !overwrite ? POLLIN : 0;
484
485 if (!evsel->system_wide &&
486 perf_evlist__add_pollfd(evlist, fd, map, revent, fdarray_flag__default) < 0) {
487 perf_mmap__put(map);
488 return -1;
489 }
490
491 if (evsel->attr.read_format & PERF_FORMAT_ID) {
492 if (perf_evlist__id_add_fd(evlist, evsel, cpu, thread,
493 fd) < 0)
494 return -1;
495 perf_evsel__set_sid_idx(evsel, idx, cpu, thread);
496 }
497 }
498
499 return 0;
500 }
501
502 static int
mmap_per_thread(struct perf_evlist * evlist,struct perf_evlist_mmap_ops * ops,struct perf_mmap_param * mp)503 mmap_per_thread(struct perf_evlist *evlist, struct perf_evlist_mmap_ops *ops,
504 struct perf_mmap_param *mp)
505 {
506 int thread;
507 int nr_threads = perf_thread_map__nr(evlist->threads);
508
509 for (thread = 0; thread < nr_threads; thread++) {
510 int output = -1;
511 int output_overwrite = -1;
512
513 if (ops->idx)
514 ops->idx(evlist, mp, thread, false);
515
516 if (mmap_per_evsel(evlist, ops, thread, mp, 0, thread,
517 &output, &output_overwrite))
518 goto out_unmap;
519 }
520
521 return 0;
522
523 out_unmap:
524 perf_evlist__munmap(evlist);
525 return -1;
526 }
527
528 static int
mmap_per_cpu(struct perf_evlist * evlist,struct perf_evlist_mmap_ops * ops,struct perf_mmap_param * mp)529 mmap_per_cpu(struct perf_evlist *evlist, struct perf_evlist_mmap_ops *ops,
530 struct perf_mmap_param *mp)
531 {
532 int nr_threads = perf_thread_map__nr(evlist->threads);
533 int nr_cpus = perf_cpu_map__nr(evlist->cpus);
534 int cpu, thread;
535
536 for (cpu = 0; cpu < nr_cpus; cpu++) {
537 int output = -1;
538 int output_overwrite = -1;
539
540 if (ops->idx)
541 ops->idx(evlist, mp, cpu, true);
542
543 for (thread = 0; thread < nr_threads; thread++) {
544 if (mmap_per_evsel(evlist, ops, cpu, mp, cpu,
545 thread, &output, &output_overwrite))
546 goto out_unmap;
547 }
548 }
549
550 return 0;
551
552 out_unmap:
553 perf_evlist__munmap(evlist);
554 return -1;
555 }
556
perf_evlist__nr_mmaps(struct perf_evlist * evlist)557 static int perf_evlist__nr_mmaps(struct perf_evlist *evlist)
558 {
559 int nr_mmaps;
560
561 nr_mmaps = perf_cpu_map__nr(evlist->cpus);
562 if (perf_cpu_map__empty(evlist->cpus))
563 nr_mmaps = perf_thread_map__nr(evlist->threads);
564
565 return nr_mmaps;
566 }
567
perf_evlist__mmap_ops(struct perf_evlist * evlist,struct perf_evlist_mmap_ops * ops,struct perf_mmap_param * mp)568 int perf_evlist__mmap_ops(struct perf_evlist *evlist,
569 struct perf_evlist_mmap_ops *ops,
570 struct perf_mmap_param *mp)
571 {
572 struct perf_evsel *evsel;
573 const struct perf_cpu_map *cpus = evlist->cpus;
574
575 if (!ops || !ops->get || !ops->mmap)
576 return -EINVAL;
577
578 mp->mask = evlist->mmap_len - page_size - 1;
579
580 evlist->nr_mmaps = perf_evlist__nr_mmaps(evlist);
581
582 perf_evlist__for_each_entry(evlist, evsel) {
583 if ((evsel->attr.read_format & PERF_FORMAT_ID) &&
584 evsel->sample_id == NULL &&
585 perf_evsel__alloc_id(evsel, evsel->fd->max_x, evsel->fd->max_y) < 0)
586 return -ENOMEM;
587 }
588
589 if (evlist->pollfd.entries == NULL && perf_evlist__alloc_pollfd(evlist) < 0)
590 return -ENOMEM;
591
592 if (perf_cpu_map__empty(cpus))
593 return mmap_per_thread(evlist, ops, mp);
594
595 return mmap_per_cpu(evlist, ops, mp);
596 }
597
perf_evlist__mmap(struct perf_evlist * evlist,int pages)598 int perf_evlist__mmap(struct perf_evlist *evlist, int pages)
599 {
600 struct perf_mmap_param mp;
601 struct perf_evlist_mmap_ops ops = {
602 .get = perf_evlist__mmap_cb_get,
603 .mmap = perf_evlist__mmap_cb_mmap,
604 };
605
606 evlist->mmap_len = (pages + 1) * page_size;
607
608 return perf_evlist__mmap_ops(evlist, &ops, &mp);
609 }
610
perf_evlist__munmap(struct perf_evlist * evlist)611 void perf_evlist__munmap(struct perf_evlist *evlist)
612 {
613 int i;
614
615 if (evlist->mmap) {
616 for (i = 0; i < evlist->nr_mmaps; i++)
617 perf_mmap__munmap(&evlist->mmap[i]);
618 }
619
620 if (evlist->mmap_ovw) {
621 for (i = 0; i < evlist->nr_mmaps; i++)
622 perf_mmap__munmap(&evlist->mmap_ovw[i]);
623 }
624
625 zfree(&evlist->mmap);
626 zfree(&evlist->mmap_ovw);
627 }
628
629 struct perf_mmap*
perf_evlist__next_mmap(struct perf_evlist * evlist,struct perf_mmap * map,bool overwrite)630 perf_evlist__next_mmap(struct perf_evlist *evlist, struct perf_mmap *map,
631 bool overwrite)
632 {
633 if (map)
634 return map->next;
635
636 return overwrite ? evlist->mmap_ovw_first : evlist->mmap_first;
637 }
638