auxtrace.c 32 KB

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  1. /*
  2. * auxtrace.c: AUX area trace support
  3. * Copyright (c) 2013-2015, Intel Corporation.
  4. *
  5. * This program is free software; you can redistribute it and/or modify it
  6. * under the terms and conditions of the GNU General Public License,
  7. * version 2, as published by the Free Software Foundation.
  8. *
  9. * This program is distributed in the hope it will be useful, but WITHOUT
  10. * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11. * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
  12. * more details.
  13. *
  14. */
  15. #include <sys/types.h>
  16. #include <sys/mman.h>
  17. #include <stdbool.h>
  18. #include <linux/kernel.h>
  19. #include <linux/perf_event.h>
  20. #include <linux/types.h>
  21. #include <linux/bitops.h>
  22. #include <linux/log2.h>
  23. #include <linux/string.h>
  24. #include <sys/param.h>
  25. #include <stdlib.h>
  26. #include <stdio.h>
  27. #include <string.h>
  28. #include <limits.h>
  29. #include <errno.h>
  30. #include <linux/list.h>
  31. #include "../perf.h"
  32. #include "util.h"
  33. #include "evlist.h"
  34. #include "cpumap.h"
  35. #include "thread_map.h"
  36. #include "asm/bug.h"
  37. #include "auxtrace.h"
  38. #include <linux/hash.h>
  39. #include "event.h"
  40. #include "session.h"
  41. #include "debug.h"
  42. #include "parse-options.h"
  43. #include "intel-pt.h"
  44. #include "intel-bts.h"
  45. int auxtrace_mmap__mmap(struct auxtrace_mmap *mm,
  46. struct auxtrace_mmap_params *mp,
  47. void *userpg, int fd)
  48. {
  49. struct perf_event_mmap_page *pc = userpg;
  50. WARN_ONCE(mm->base, "Uninitialized auxtrace_mmap\n");
  51. mm->userpg = userpg;
  52. mm->mask = mp->mask;
  53. mm->len = mp->len;
  54. mm->prev = 0;
  55. mm->idx = mp->idx;
  56. mm->tid = mp->tid;
  57. mm->cpu = mp->cpu;
  58. if (!mp->len) {
  59. mm->base = NULL;
  60. return 0;
  61. }
  62. #if BITS_PER_LONG != 64 && !defined(HAVE_SYNC_COMPARE_AND_SWAP_SUPPORT)
  63. pr_err("Cannot use AUX area tracing mmaps\n");
  64. return -1;
  65. #endif
  66. pc->aux_offset = mp->offset;
  67. pc->aux_size = mp->len;
  68. mm->base = mmap(NULL, mp->len, mp->prot, MAP_SHARED, fd, mp->offset);
  69. if (mm->base == MAP_FAILED) {
  70. pr_debug2("failed to mmap AUX area\n");
  71. mm->base = NULL;
  72. return -1;
  73. }
  74. return 0;
  75. }
  76. void auxtrace_mmap__munmap(struct auxtrace_mmap *mm)
  77. {
  78. if (mm->base) {
  79. munmap(mm->base, mm->len);
  80. mm->base = NULL;
  81. }
  82. }
  83. void auxtrace_mmap_params__init(struct auxtrace_mmap_params *mp,
  84. off_t auxtrace_offset,
  85. unsigned int auxtrace_pages,
  86. bool auxtrace_overwrite)
  87. {
  88. if (auxtrace_pages) {
  89. mp->offset = auxtrace_offset;
  90. mp->len = auxtrace_pages * (size_t)page_size;
  91. mp->mask = is_power_of_2(mp->len) ? mp->len - 1 : 0;
  92. mp->prot = PROT_READ | (auxtrace_overwrite ? 0 : PROT_WRITE);
  93. pr_debug2("AUX area mmap length %zu\n", mp->len);
  94. } else {
  95. mp->len = 0;
  96. }
  97. }
  98. void auxtrace_mmap_params__set_idx(struct auxtrace_mmap_params *mp,
  99. struct perf_evlist *evlist, int idx,
  100. bool per_cpu)
  101. {
  102. mp->idx = idx;
  103. if (per_cpu) {
  104. mp->cpu = evlist->cpus->map[idx];
  105. if (evlist->threads)
  106. mp->tid = thread_map__pid(evlist->threads, 0);
  107. else
  108. mp->tid = -1;
  109. } else {
  110. mp->cpu = -1;
  111. mp->tid = thread_map__pid(evlist->threads, idx);
  112. }
  113. }
  114. #define AUXTRACE_INIT_NR_QUEUES 32
  115. static struct auxtrace_queue *auxtrace_alloc_queue_array(unsigned int nr_queues)
  116. {
  117. struct auxtrace_queue *queue_array;
  118. unsigned int max_nr_queues, i;
  119. max_nr_queues = UINT_MAX / sizeof(struct auxtrace_queue);
  120. if (nr_queues > max_nr_queues)
  121. return NULL;
  122. queue_array = calloc(nr_queues, sizeof(struct auxtrace_queue));
  123. if (!queue_array)
  124. return NULL;
  125. for (i = 0; i < nr_queues; i++) {
  126. INIT_LIST_HEAD(&queue_array[i].head);
  127. queue_array[i].priv = NULL;
  128. }
  129. return queue_array;
  130. }
  131. int auxtrace_queues__init(struct auxtrace_queues *queues)
  132. {
  133. queues->nr_queues = AUXTRACE_INIT_NR_QUEUES;
  134. queues->queue_array = auxtrace_alloc_queue_array(queues->nr_queues);
  135. if (!queues->queue_array)
  136. return -ENOMEM;
  137. return 0;
  138. }
  139. static int auxtrace_queues__grow(struct auxtrace_queues *queues,
  140. unsigned int new_nr_queues)
  141. {
  142. unsigned int nr_queues = queues->nr_queues;
  143. struct auxtrace_queue *queue_array;
  144. unsigned int i;
  145. if (!nr_queues)
  146. nr_queues = AUXTRACE_INIT_NR_QUEUES;
  147. while (nr_queues && nr_queues < new_nr_queues)
  148. nr_queues <<= 1;
  149. if (nr_queues < queues->nr_queues || nr_queues < new_nr_queues)
  150. return -EINVAL;
  151. queue_array = auxtrace_alloc_queue_array(nr_queues);
  152. if (!queue_array)
  153. return -ENOMEM;
  154. for (i = 0; i < queues->nr_queues; i++) {
  155. list_splice_tail(&queues->queue_array[i].head,
  156. &queue_array[i].head);
  157. queue_array[i].tid = queues->queue_array[i].tid;
  158. queue_array[i].cpu = queues->queue_array[i].cpu;
  159. queue_array[i].set = queues->queue_array[i].set;
  160. queue_array[i].priv = queues->queue_array[i].priv;
  161. }
  162. queues->nr_queues = nr_queues;
  163. queues->queue_array = queue_array;
  164. return 0;
  165. }
  166. static void *auxtrace_copy_data(u64 size, struct perf_session *session)
  167. {
  168. int fd = perf_data_file__fd(session->file);
  169. void *p;
  170. ssize_t ret;
  171. if (size > SSIZE_MAX)
  172. return NULL;
  173. p = malloc(size);
  174. if (!p)
  175. return NULL;
  176. ret = readn(fd, p, size);
  177. if (ret != (ssize_t)size) {
  178. free(p);
  179. return NULL;
  180. }
  181. return p;
  182. }
  183. static int auxtrace_queues__add_buffer(struct auxtrace_queues *queues,
  184. unsigned int idx,
  185. struct auxtrace_buffer *buffer)
  186. {
  187. struct auxtrace_queue *queue;
  188. int err;
  189. if (idx >= queues->nr_queues) {
  190. err = auxtrace_queues__grow(queues, idx + 1);
  191. if (err)
  192. return err;
  193. }
  194. queue = &queues->queue_array[idx];
  195. if (!queue->set) {
  196. queue->set = true;
  197. queue->tid = buffer->tid;
  198. queue->cpu = buffer->cpu;
  199. } else if (buffer->cpu != queue->cpu || buffer->tid != queue->tid) {
  200. pr_err("auxtrace queue conflict: cpu %d, tid %d vs cpu %d, tid %d\n",
  201. queue->cpu, queue->tid, buffer->cpu, buffer->tid);
  202. return -EINVAL;
  203. }
  204. buffer->buffer_nr = queues->next_buffer_nr++;
  205. list_add_tail(&buffer->list, &queue->head);
  206. queues->new_data = true;
  207. queues->populated = true;
  208. return 0;
  209. }
  210. /* Limit buffers to 32MiB on 32-bit */
  211. #define BUFFER_LIMIT_FOR_32_BIT (32 * 1024 * 1024)
  212. static int auxtrace_queues__split_buffer(struct auxtrace_queues *queues,
  213. unsigned int idx,
  214. struct auxtrace_buffer *buffer)
  215. {
  216. u64 sz = buffer->size;
  217. bool consecutive = false;
  218. struct auxtrace_buffer *b;
  219. int err;
  220. while (sz > BUFFER_LIMIT_FOR_32_BIT) {
  221. b = memdup(buffer, sizeof(struct auxtrace_buffer));
  222. if (!b)
  223. return -ENOMEM;
  224. b->size = BUFFER_LIMIT_FOR_32_BIT;
  225. b->consecutive = consecutive;
  226. err = auxtrace_queues__add_buffer(queues, idx, b);
  227. if (err) {
  228. auxtrace_buffer__free(b);
  229. return err;
  230. }
  231. buffer->data_offset += BUFFER_LIMIT_FOR_32_BIT;
  232. sz -= BUFFER_LIMIT_FOR_32_BIT;
  233. consecutive = true;
  234. }
  235. buffer->size = sz;
  236. buffer->consecutive = consecutive;
  237. return 0;
  238. }
  239. static int auxtrace_queues__add_event_buffer(struct auxtrace_queues *queues,
  240. struct perf_session *session,
  241. unsigned int idx,
  242. struct auxtrace_buffer *buffer)
  243. {
  244. if (session->one_mmap) {
  245. buffer->data = buffer->data_offset - session->one_mmap_offset +
  246. session->one_mmap_addr;
  247. } else if (perf_data_file__is_pipe(session->file)) {
  248. buffer->data = auxtrace_copy_data(buffer->size, session);
  249. if (!buffer->data)
  250. return -ENOMEM;
  251. buffer->data_needs_freeing = true;
  252. } else if (BITS_PER_LONG == 32 &&
  253. buffer->size > BUFFER_LIMIT_FOR_32_BIT) {
  254. int err;
  255. err = auxtrace_queues__split_buffer(queues, idx, buffer);
  256. if (err)
  257. return err;
  258. }
  259. return auxtrace_queues__add_buffer(queues, idx, buffer);
  260. }
  261. int auxtrace_queues__add_event(struct auxtrace_queues *queues,
  262. struct perf_session *session,
  263. union perf_event *event, off_t data_offset,
  264. struct auxtrace_buffer **buffer_ptr)
  265. {
  266. struct auxtrace_buffer *buffer;
  267. unsigned int idx;
  268. int err;
  269. buffer = zalloc(sizeof(struct auxtrace_buffer));
  270. if (!buffer)
  271. return -ENOMEM;
  272. buffer->pid = -1;
  273. buffer->tid = event->auxtrace.tid;
  274. buffer->cpu = event->auxtrace.cpu;
  275. buffer->data_offset = data_offset;
  276. buffer->offset = event->auxtrace.offset;
  277. buffer->reference = event->auxtrace.reference;
  278. buffer->size = event->auxtrace.size;
  279. idx = event->auxtrace.idx;
  280. err = auxtrace_queues__add_event_buffer(queues, session, idx, buffer);
  281. if (err)
  282. goto out_err;
  283. if (buffer_ptr)
  284. *buffer_ptr = buffer;
  285. return 0;
  286. out_err:
  287. auxtrace_buffer__free(buffer);
  288. return err;
  289. }
  290. static int auxtrace_queues__add_indexed_event(struct auxtrace_queues *queues,
  291. struct perf_session *session,
  292. off_t file_offset, size_t sz)
  293. {
  294. union perf_event *event;
  295. int err;
  296. char buf[PERF_SAMPLE_MAX_SIZE];
  297. err = perf_session__peek_event(session, file_offset, buf,
  298. PERF_SAMPLE_MAX_SIZE, &event, NULL);
  299. if (err)
  300. return err;
  301. if (event->header.type == PERF_RECORD_AUXTRACE) {
  302. if (event->header.size < sizeof(struct auxtrace_event) ||
  303. event->header.size != sz) {
  304. err = -EINVAL;
  305. goto out;
  306. }
  307. file_offset += event->header.size;
  308. err = auxtrace_queues__add_event(queues, session, event,
  309. file_offset, NULL);
  310. }
  311. out:
  312. return err;
  313. }
  314. void auxtrace_queues__free(struct auxtrace_queues *queues)
  315. {
  316. unsigned int i;
  317. for (i = 0; i < queues->nr_queues; i++) {
  318. while (!list_empty(&queues->queue_array[i].head)) {
  319. struct auxtrace_buffer *buffer;
  320. buffer = list_entry(queues->queue_array[i].head.next,
  321. struct auxtrace_buffer, list);
  322. list_del(&buffer->list);
  323. auxtrace_buffer__free(buffer);
  324. }
  325. }
  326. zfree(&queues->queue_array);
  327. queues->nr_queues = 0;
  328. }
  329. static void auxtrace_heapify(struct auxtrace_heap_item *heap_array,
  330. unsigned int pos, unsigned int queue_nr,
  331. u64 ordinal)
  332. {
  333. unsigned int parent;
  334. while (pos) {
  335. parent = (pos - 1) >> 1;
  336. if (heap_array[parent].ordinal <= ordinal)
  337. break;
  338. heap_array[pos] = heap_array[parent];
  339. pos = parent;
  340. }
  341. heap_array[pos].queue_nr = queue_nr;
  342. heap_array[pos].ordinal = ordinal;
  343. }
  344. int auxtrace_heap__add(struct auxtrace_heap *heap, unsigned int queue_nr,
  345. u64 ordinal)
  346. {
  347. struct auxtrace_heap_item *heap_array;
  348. if (queue_nr >= heap->heap_sz) {
  349. unsigned int heap_sz = AUXTRACE_INIT_NR_QUEUES;
  350. while (heap_sz <= queue_nr)
  351. heap_sz <<= 1;
  352. heap_array = realloc(heap->heap_array,
  353. heap_sz * sizeof(struct auxtrace_heap_item));
  354. if (!heap_array)
  355. return -ENOMEM;
  356. heap->heap_array = heap_array;
  357. heap->heap_sz = heap_sz;
  358. }
  359. auxtrace_heapify(heap->heap_array, heap->heap_cnt++, queue_nr, ordinal);
  360. return 0;
  361. }
  362. void auxtrace_heap__free(struct auxtrace_heap *heap)
  363. {
  364. zfree(&heap->heap_array);
  365. heap->heap_cnt = 0;
  366. heap->heap_sz = 0;
  367. }
  368. void auxtrace_heap__pop(struct auxtrace_heap *heap)
  369. {
  370. unsigned int pos, last, heap_cnt = heap->heap_cnt;
  371. struct auxtrace_heap_item *heap_array;
  372. if (!heap_cnt)
  373. return;
  374. heap->heap_cnt -= 1;
  375. heap_array = heap->heap_array;
  376. pos = 0;
  377. while (1) {
  378. unsigned int left, right;
  379. left = (pos << 1) + 1;
  380. if (left >= heap_cnt)
  381. break;
  382. right = left + 1;
  383. if (right >= heap_cnt) {
  384. heap_array[pos] = heap_array[left];
  385. return;
  386. }
  387. if (heap_array[left].ordinal < heap_array[right].ordinal) {
  388. heap_array[pos] = heap_array[left];
  389. pos = left;
  390. } else {
  391. heap_array[pos] = heap_array[right];
  392. pos = right;
  393. }
  394. }
  395. last = heap_cnt - 1;
  396. auxtrace_heapify(heap_array, pos, heap_array[last].queue_nr,
  397. heap_array[last].ordinal);
  398. }
  399. size_t auxtrace_record__info_priv_size(struct auxtrace_record *itr)
  400. {
  401. if (itr)
  402. return itr->info_priv_size(itr);
  403. return 0;
  404. }
  405. static int auxtrace_not_supported(void)
  406. {
  407. pr_err("AUX area tracing is not supported on this architecture\n");
  408. return -EINVAL;
  409. }
  410. int auxtrace_record__info_fill(struct auxtrace_record *itr,
  411. struct perf_session *session,
  412. struct auxtrace_info_event *auxtrace_info,
  413. size_t priv_size)
  414. {
  415. if (itr)
  416. return itr->info_fill(itr, session, auxtrace_info, priv_size);
  417. return auxtrace_not_supported();
  418. }
  419. void auxtrace_record__free(struct auxtrace_record *itr)
  420. {
  421. if (itr)
  422. itr->free(itr);
  423. }
  424. int auxtrace_record__snapshot_start(struct auxtrace_record *itr)
  425. {
  426. if (itr && itr->snapshot_start)
  427. return itr->snapshot_start(itr);
  428. return 0;
  429. }
  430. int auxtrace_record__snapshot_finish(struct auxtrace_record *itr)
  431. {
  432. if (itr && itr->snapshot_finish)
  433. return itr->snapshot_finish(itr);
  434. return 0;
  435. }
  436. int auxtrace_record__find_snapshot(struct auxtrace_record *itr, int idx,
  437. struct auxtrace_mmap *mm,
  438. unsigned char *data, u64 *head, u64 *old)
  439. {
  440. if (itr && itr->find_snapshot)
  441. return itr->find_snapshot(itr, idx, mm, data, head, old);
  442. return 0;
  443. }
  444. int auxtrace_record__options(struct auxtrace_record *itr,
  445. struct perf_evlist *evlist,
  446. struct record_opts *opts)
  447. {
  448. if (itr)
  449. return itr->recording_options(itr, evlist, opts);
  450. return 0;
  451. }
  452. u64 auxtrace_record__reference(struct auxtrace_record *itr)
  453. {
  454. if (itr)
  455. return itr->reference(itr);
  456. return 0;
  457. }
  458. int auxtrace_parse_snapshot_options(struct auxtrace_record *itr,
  459. struct record_opts *opts, const char *str)
  460. {
  461. if (!str)
  462. return 0;
  463. if (itr)
  464. return itr->parse_snapshot_options(itr, opts, str);
  465. pr_err("No AUX area tracing to snapshot\n");
  466. return -EINVAL;
  467. }
  468. struct auxtrace_record *__weak
  469. auxtrace_record__init(struct perf_evlist *evlist __maybe_unused, int *err)
  470. {
  471. *err = 0;
  472. return NULL;
  473. }
  474. static int auxtrace_index__alloc(struct list_head *head)
  475. {
  476. struct auxtrace_index *auxtrace_index;
  477. auxtrace_index = malloc(sizeof(struct auxtrace_index));
  478. if (!auxtrace_index)
  479. return -ENOMEM;
  480. auxtrace_index->nr = 0;
  481. INIT_LIST_HEAD(&auxtrace_index->list);
  482. list_add_tail(&auxtrace_index->list, head);
  483. return 0;
  484. }
  485. void auxtrace_index__free(struct list_head *head)
  486. {
  487. struct auxtrace_index *auxtrace_index, *n;
  488. list_for_each_entry_safe(auxtrace_index, n, head, list) {
  489. list_del(&auxtrace_index->list);
  490. free(auxtrace_index);
  491. }
  492. }
  493. static struct auxtrace_index *auxtrace_index__last(struct list_head *head)
  494. {
  495. struct auxtrace_index *auxtrace_index;
  496. int err;
  497. if (list_empty(head)) {
  498. err = auxtrace_index__alloc(head);
  499. if (err)
  500. return NULL;
  501. }
  502. auxtrace_index = list_entry(head->prev, struct auxtrace_index, list);
  503. if (auxtrace_index->nr >= PERF_AUXTRACE_INDEX_ENTRY_COUNT) {
  504. err = auxtrace_index__alloc(head);
  505. if (err)
  506. return NULL;
  507. auxtrace_index = list_entry(head->prev, struct auxtrace_index,
  508. list);
  509. }
  510. return auxtrace_index;
  511. }
  512. int auxtrace_index__auxtrace_event(struct list_head *head,
  513. union perf_event *event, off_t file_offset)
  514. {
  515. struct auxtrace_index *auxtrace_index;
  516. size_t nr;
  517. auxtrace_index = auxtrace_index__last(head);
  518. if (!auxtrace_index)
  519. return -ENOMEM;
  520. nr = auxtrace_index->nr;
  521. auxtrace_index->entries[nr].file_offset = file_offset;
  522. auxtrace_index->entries[nr].sz = event->header.size;
  523. auxtrace_index->nr += 1;
  524. return 0;
  525. }
  526. static int auxtrace_index__do_write(int fd,
  527. struct auxtrace_index *auxtrace_index)
  528. {
  529. struct auxtrace_index_entry ent;
  530. size_t i;
  531. for (i = 0; i < auxtrace_index->nr; i++) {
  532. ent.file_offset = auxtrace_index->entries[i].file_offset;
  533. ent.sz = auxtrace_index->entries[i].sz;
  534. if (writen(fd, &ent, sizeof(ent)) != sizeof(ent))
  535. return -errno;
  536. }
  537. return 0;
  538. }
  539. int auxtrace_index__write(int fd, struct list_head *head)
  540. {
  541. struct auxtrace_index *auxtrace_index;
  542. u64 total = 0;
  543. int err;
  544. list_for_each_entry(auxtrace_index, head, list)
  545. total += auxtrace_index->nr;
  546. if (writen(fd, &total, sizeof(total)) != sizeof(total))
  547. return -errno;
  548. list_for_each_entry(auxtrace_index, head, list) {
  549. err = auxtrace_index__do_write(fd, auxtrace_index);
  550. if (err)
  551. return err;
  552. }
  553. return 0;
  554. }
  555. static int auxtrace_index__process_entry(int fd, struct list_head *head,
  556. bool needs_swap)
  557. {
  558. struct auxtrace_index *auxtrace_index;
  559. struct auxtrace_index_entry ent;
  560. size_t nr;
  561. if (readn(fd, &ent, sizeof(ent)) != sizeof(ent))
  562. return -1;
  563. auxtrace_index = auxtrace_index__last(head);
  564. if (!auxtrace_index)
  565. return -1;
  566. nr = auxtrace_index->nr;
  567. if (needs_swap) {
  568. auxtrace_index->entries[nr].file_offset =
  569. bswap_64(ent.file_offset);
  570. auxtrace_index->entries[nr].sz = bswap_64(ent.sz);
  571. } else {
  572. auxtrace_index->entries[nr].file_offset = ent.file_offset;
  573. auxtrace_index->entries[nr].sz = ent.sz;
  574. }
  575. auxtrace_index->nr = nr + 1;
  576. return 0;
  577. }
  578. int auxtrace_index__process(int fd, u64 size, struct perf_session *session,
  579. bool needs_swap)
  580. {
  581. struct list_head *head = &session->auxtrace_index;
  582. u64 nr;
  583. if (readn(fd, &nr, sizeof(u64)) != sizeof(u64))
  584. return -1;
  585. if (needs_swap)
  586. nr = bswap_64(nr);
  587. if (sizeof(u64) + nr * sizeof(struct auxtrace_index_entry) > size)
  588. return -1;
  589. while (nr--) {
  590. int err;
  591. err = auxtrace_index__process_entry(fd, head, needs_swap);
  592. if (err)
  593. return -1;
  594. }
  595. return 0;
  596. }
  597. static int auxtrace_queues__process_index_entry(struct auxtrace_queues *queues,
  598. struct perf_session *session,
  599. struct auxtrace_index_entry *ent)
  600. {
  601. return auxtrace_queues__add_indexed_event(queues, session,
  602. ent->file_offset, ent->sz);
  603. }
  604. int auxtrace_queues__process_index(struct auxtrace_queues *queues,
  605. struct perf_session *session)
  606. {
  607. struct auxtrace_index *auxtrace_index;
  608. struct auxtrace_index_entry *ent;
  609. size_t i;
  610. int err;
  611. list_for_each_entry(auxtrace_index, &session->auxtrace_index, list) {
  612. for (i = 0; i < auxtrace_index->nr; i++) {
  613. ent = &auxtrace_index->entries[i];
  614. err = auxtrace_queues__process_index_entry(queues,
  615. session,
  616. ent);
  617. if (err)
  618. return err;
  619. }
  620. }
  621. return 0;
  622. }
  623. struct auxtrace_buffer *auxtrace_buffer__next(struct auxtrace_queue *queue,
  624. struct auxtrace_buffer *buffer)
  625. {
  626. if (buffer) {
  627. if (list_is_last(&buffer->list, &queue->head))
  628. return NULL;
  629. return list_entry(buffer->list.next, struct auxtrace_buffer,
  630. list);
  631. } else {
  632. if (list_empty(&queue->head))
  633. return NULL;
  634. return list_entry(queue->head.next, struct auxtrace_buffer,
  635. list);
  636. }
  637. }
  638. void *auxtrace_buffer__get_data(struct auxtrace_buffer *buffer, int fd)
  639. {
  640. size_t adj = buffer->data_offset & (page_size - 1);
  641. size_t size = buffer->size + adj;
  642. off_t file_offset = buffer->data_offset - adj;
  643. void *addr;
  644. if (buffer->data)
  645. return buffer->data;
  646. addr = mmap(NULL, size, PROT_READ, MAP_SHARED, fd, file_offset);
  647. if (addr == MAP_FAILED)
  648. return NULL;
  649. buffer->mmap_addr = addr;
  650. buffer->mmap_size = size;
  651. buffer->data = addr + adj;
  652. return buffer->data;
  653. }
  654. void auxtrace_buffer__put_data(struct auxtrace_buffer *buffer)
  655. {
  656. if (!buffer->data || !buffer->mmap_addr)
  657. return;
  658. munmap(buffer->mmap_addr, buffer->mmap_size);
  659. buffer->mmap_addr = NULL;
  660. buffer->mmap_size = 0;
  661. buffer->data = NULL;
  662. buffer->use_data = NULL;
  663. }
  664. void auxtrace_buffer__drop_data(struct auxtrace_buffer *buffer)
  665. {
  666. auxtrace_buffer__put_data(buffer);
  667. if (buffer->data_needs_freeing) {
  668. buffer->data_needs_freeing = false;
  669. zfree(&buffer->data);
  670. buffer->use_data = NULL;
  671. buffer->size = 0;
  672. }
  673. }
  674. void auxtrace_buffer__free(struct auxtrace_buffer *buffer)
  675. {
  676. auxtrace_buffer__drop_data(buffer);
  677. free(buffer);
  678. }
  679. void auxtrace_synth_error(struct auxtrace_error_event *auxtrace_error, int type,
  680. int code, int cpu, pid_t pid, pid_t tid, u64 ip,
  681. const char *msg)
  682. {
  683. size_t size;
  684. memset(auxtrace_error, 0, sizeof(struct auxtrace_error_event));
  685. auxtrace_error->header.type = PERF_RECORD_AUXTRACE_ERROR;
  686. auxtrace_error->type = type;
  687. auxtrace_error->code = code;
  688. auxtrace_error->cpu = cpu;
  689. auxtrace_error->pid = pid;
  690. auxtrace_error->tid = tid;
  691. auxtrace_error->ip = ip;
  692. strlcpy(auxtrace_error->msg, msg, MAX_AUXTRACE_ERROR_MSG);
  693. size = (void *)auxtrace_error->msg - (void *)auxtrace_error +
  694. strlen(auxtrace_error->msg) + 1;
  695. auxtrace_error->header.size = PERF_ALIGN(size, sizeof(u64));
  696. }
  697. int perf_event__synthesize_auxtrace_info(struct auxtrace_record *itr,
  698. struct perf_tool *tool,
  699. struct perf_session *session,
  700. perf_event__handler_t process)
  701. {
  702. union perf_event *ev;
  703. size_t priv_size;
  704. int err;
  705. pr_debug2("Synthesizing auxtrace information\n");
  706. priv_size = auxtrace_record__info_priv_size(itr);
  707. ev = zalloc(sizeof(struct auxtrace_info_event) + priv_size);
  708. if (!ev)
  709. return -ENOMEM;
  710. ev->auxtrace_info.header.type = PERF_RECORD_AUXTRACE_INFO;
  711. ev->auxtrace_info.header.size = sizeof(struct auxtrace_info_event) +
  712. priv_size;
  713. err = auxtrace_record__info_fill(itr, session, &ev->auxtrace_info,
  714. priv_size);
  715. if (err)
  716. goto out_free;
  717. err = process(tool, ev, NULL, NULL);
  718. out_free:
  719. free(ev);
  720. return err;
  721. }
  722. static bool auxtrace__dont_decode(struct perf_session *session)
  723. {
  724. return !session->itrace_synth_opts ||
  725. session->itrace_synth_opts->dont_decode;
  726. }
  727. int perf_event__process_auxtrace_info(struct perf_tool *tool __maybe_unused,
  728. union perf_event *event,
  729. struct perf_session *session)
  730. {
  731. enum auxtrace_type type = event->auxtrace_info.type;
  732. if (dump_trace)
  733. fprintf(stdout, " type: %u\n", type);
  734. switch (type) {
  735. case PERF_AUXTRACE_INTEL_PT:
  736. return intel_pt_process_auxtrace_info(event, session);
  737. case PERF_AUXTRACE_INTEL_BTS:
  738. return intel_bts_process_auxtrace_info(event, session);
  739. case PERF_AUXTRACE_UNKNOWN:
  740. default:
  741. return -EINVAL;
  742. }
  743. }
  744. s64 perf_event__process_auxtrace(struct perf_tool *tool,
  745. union perf_event *event,
  746. struct perf_session *session)
  747. {
  748. s64 err;
  749. if (dump_trace)
  750. fprintf(stdout, " size: %#"PRIx64" offset: %#"PRIx64" ref: %#"PRIx64" idx: %u tid: %d cpu: %d\n",
  751. event->auxtrace.size, event->auxtrace.offset,
  752. event->auxtrace.reference, event->auxtrace.idx,
  753. event->auxtrace.tid, event->auxtrace.cpu);
  754. if (auxtrace__dont_decode(session))
  755. return event->auxtrace.size;
  756. if (!session->auxtrace || event->header.type != PERF_RECORD_AUXTRACE)
  757. return -EINVAL;
  758. err = session->auxtrace->process_auxtrace_event(session, event, tool);
  759. if (err < 0)
  760. return err;
  761. return event->auxtrace.size;
  762. }
  763. #define PERF_ITRACE_DEFAULT_PERIOD_TYPE PERF_ITRACE_PERIOD_NANOSECS
  764. #define PERF_ITRACE_DEFAULT_PERIOD 100000
  765. #define PERF_ITRACE_DEFAULT_CALLCHAIN_SZ 16
  766. #define PERF_ITRACE_MAX_CALLCHAIN_SZ 1024
  767. #define PERF_ITRACE_DEFAULT_LAST_BRANCH_SZ 64
  768. #define PERF_ITRACE_MAX_LAST_BRANCH_SZ 1024
  769. void itrace_synth_opts__set_default(struct itrace_synth_opts *synth_opts)
  770. {
  771. synth_opts->instructions = true;
  772. synth_opts->branches = true;
  773. synth_opts->transactions = true;
  774. synth_opts->errors = true;
  775. synth_opts->period_type = PERF_ITRACE_DEFAULT_PERIOD_TYPE;
  776. synth_opts->period = PERF_ITRACE_DEFAULT_PERIOD;
  777. synth_opts->callchain_sz = PERF_ITRACE_DEFAULT_CALLCHAIN_SZ;
  778. synth_opts->last_branch_sz = PERF_ITRACE_DEFAULT_LAST_BRANCH_SZ;
  779. }
  780. /*
  781. * Please check tools/perf/Documentation/perf-script.txt for information
  782. * about the options parsed here, which is introduced after this cset,
  783. * when support in 'perf script' for these options is introduced.
  784. */
  785. int itrace_parse_synth_opts(const struct option *opt, const char *str,
  786. int unset)
  787. {
  788. struct itrace_synth_opts *synth_opts = opt->value;
  789. const char *p;
  790. char *endptr;
  791. bool period_type_set = false;
  792. bool period_set = false;
  793. synth_opts->set = true;
  794. if (unset) {
  795. synth_opts->dont_decode = true;
  796. return 0;
  797. }
  798. if (!str) {
  799. itrace_synth_opts__set_default(synth_opts);
  800. return 0;
  801. }
  802. for (p = str; *p;) {
  803. switch (*p++) {
  804. case 'i':
  805. synth_opts->instructions = true;
  806. while (*p == ' ' || *p == ',')
  807. p += 1;
  808. if (isdigit(*p)) {
  809. synth_opts->period = strtoull(p, &endptr, 10);
  810. period_set = true;
  811. p = endptr;
  812. while (*p == ' ' || *p == ',')
  813. p += 1;
  814. switch (*p++) {
  815. case 'i':
  816. synth_opts->period_type =
  817. PERF_ITRACE_PERIOD_INSTRUCTIONS;
  818. period_type_set = true;
  819. break;
  820. case 't':
  821. synth_opts->period_type =
  822. PERF_ITRACE_PERIOD_TICKS;
  823. period_type_set = true;
  824. break;
  825. case 'm':
  826. synth_opts->period *= 1000;
  827. /* Fall through */
  828. case 'u':
  829. synth_opts->period *= 1000;
  830. /* Fall through */
  831. case 'n':
  832. if (*p++ != 's')
  833. goto out_err;
  834. synth_opts->period_type =
  835. PERF_ITRACE_PERIOD_NANOSECS;
  836. period_type_set = true;
  837. break;
  838. case '\0':
  839. goto out;
  840. default:
  841. goto out_err;
  842. }
  843. }
  844. break;
  845. case 'b':
  846. synth_opts->branches = true;
  847. break;
  848. case 'x':
  849. synth_opts->transactions = true;
  850. break;
  851. case 'e':
  852. synth_opts->errors = true;
  853. break;
  854. case 'd':
  855. synth_opts->log = true;
  856. break;
  857. case 'c':
  858. synth_opts->branches = true;
  859. synth_opts->calls = true;
  860. break;
  861. case 'r':
  862. synth_opts->branches = true;
  863. synth_opts->returns = true;
  864. break;
  865. case 'g':
  866. synth_opts->callchain = true;
  867. synth_opts->callchain_sz =
  868. PERF_ITRACE_DEFAULT_CALLCHAIN_SZ;
  869. while (*p == ' ' || *p == ',')
  870. p += 1;
  871. if (isdigit(*p)) {
  872. unsigned int val;
  873. val = strtoul(p, &endptr, 10);
  874. p = endptr;
  875. if (!val || val > PERF_ITRACE_MAX_CALLCHAIN_SZ)
  876. goto out_err;
  877. synth_opts->callchain_sz = val;
  878. }
  879. break;
  880. case 'l':
  881. synth_opts->last_branch = true;
  882. synth_opts->last_branch_sz =
  883. PERF_ITRACE_DEFAULT_LAST_BRANCH_SZ;
  884. while (*p == ' ' || *p == ',')
  885. p += 1;
  886. if (isdigit(*p)) {
  887. unsigned int val;
  888. val = strtoul(p, &endptr, 10);
  889. p = endptr;
  890. if (!val ||
  891. val > PERF_ITRACE_MAX_LAST_BRANCH_SZ)
  892. goto out_err;
  893. synth_opts->last_branch_sz = val;
  894. }
  895. break;
  896. case ' ':
  897. case ',':
  898. break;
  899. default:
  900. goto out_err;
  901. }
  902. }
  903. out:
  904. if (synth_opts->instructions) {
  905. if (!period_type_set)
  906. synth_opts->period_type =
  907. PERF_ITRACE_DEFAULT_PERIOD_TYPE;
  908. if (!period_set)
  909. synth_opts->period = PERF_ITRACE_DEFAULT_PERIOD;
  910. }
  911. return 0;
  912. out_err:
  913. pr_err("Bad Instruction Tracing options '%s'\n", str);
  914. return -EINVAL;
  915. }
  916. static const char * const auxtrace_error_type_name[] = {
  917. [PERF_AUXTRACE_ERROR_ITRACE] = "instruction trace",
  918. };
  919. static const char *auxtrace_error_name(int type)
  920. {
  921. const char *error_type_name = NULL;
  922. if (type < PERF_AUXTRACE_ERROR_MAX)
  923. error_type_name = auxtrace_error_type_name[type];
  924. if (!error_type_name)
  925. error_type_name = "unknown AUX";
  926. return error_type_name;
  927. }
  928. size_t perf_event__fprintf_auxtrace_error(union perf_event *event, FILE *fp)
  929. {
  930. struct auxtrace_error_event *e = &event->auxtrace_error;
  931. int ret;
  932. ret = fprintf(fp, " %s error type %u",
  933. auxtrace_error_name(e->type), e->type);
  934. ret += fprintf(fp, " cpu %d pid %d tid %d ip %#"PRIx64" code %u: %s\n",
  935. e->cpu, e->pid, e->tid, e->ip, e->code, e->msg);
  936. return ret;
  937. }
  938. void perf_session__auxtrace_error_inc(struct perf_session *session,
  939. union perf_event *event)
  940. {
  941. struct auxtrace_error_event *e = &event->auxtrace_error;
  942. if (e->type < PERF_AUXTRACE_ERROR_MAX)
  943. session->evlist->stats.nr_auxtrace_errors[e->type] += 1;
  944. }
  945. void events_stats__auxtrace_error_warn(const struct events_stats *stats)
  946. {
  947. int i;
  948. for (i = 0; i < PERF_AUXTRACE_ERROR_MAX; i++) {
  949. if (!stats->nr_auxtrace_errors[i])
  950. continue;
  951. ui__warning("%u %s errors\n",
  952. stats->nr_auxtrace_errors[i],
  953. auxtrace_error_name(i));
  954. }
  955. }
  956. int perf_event__process_auxtrace_error(struct perf_tool *tool __maybe_unused,
  957. union perf_event *event,
  958. struct perf_session *session)
  959. {
  960. if (auxtrace__dont_decode(session))
  961. return 0;
  962. perf_event__fprintf_auxtrace_error(event, stdout);
  963. return 0;
  964. }
  965. static int __auxtrace_mmap__read(struct auxtrace_mmap *mm,
  966. struct auxtrace_record *itr,
  967. struct perf_tool *tool, process_auxtrace_t fn,
  968. bool snapshot, size_t snapshot_size)
  969. {
  970. u64 head, old = mm->prev, offset, ref;
  971. unsigned char *data = mm->base;
  972. size_t size, head_off, old_off, len1, len2, padding;
  973. union perf_event ev;
  974. void *data1, *data2;
  975. if (snapshot) {
  976. head = auxtrace_mmap__read_snapshot_head(mm);
  977. if (auxtrace_record__find_snapshot(itr, mm->idx, mm, data,
  978. &head, &old))
  979. return -1;
  980. } else {
  981. head = auxtrace_mmap__read_head(mm);
  982. }
  983. if (old == head)
  984. return 0;
  985. pr_debug3("auxtrace idx %d old %#"PRIx64" head %#"PRIx64" diff %#"PRIx64"\n",
  986. mm->idx, old, head, head - old);
  987. if (mm->mask) {
  988. head_off = head & mm->mask;
  989. old_off = old & mm->mask;
  990. } else {
  991. head_off = head % mm->len;
  992. old_off = old % mm->len;
  993. }
  994. if (head_off > old_off)
  995. size = head_off - old_off;
  996. else
  997. size = mm->len - (old_off - head_off);
  998. if (snapshot && size > snapshot_size)
  999. size = snapshot_size;
  1000. ref = auxtrace_record__reference(itr);
  1001. if (head > old || size <= head || mm->mask) {
  1002. offset = head - size;
  1003. } else {
  1004. /*
  1005. * When the buffer size is not a power of 2, 'head' wraps at the
  1006. * highest multiple of the buffer size, so we have to subtract
  1007. * the remainder here.
  1008. */
  1009. u64 rem = (0ULL - mm->len) % mm->len;
  1010. offset = head - size - rem;
  1011. }
  1012. if (size > head_off) {
  1013. len1 = size - head_off;
  1014. data1 = &data[mm->len - len1];
  1015. len2 = head_off;
  1016. data2 = &data[0];
  1017. } else {
  1018. len1 = size;
  1019. data1 = &data[head_off - len1];
  1020. len2 = 0;
  1021. data2 = NULL;
  1022. }
  1023. if (itr->alignment) {
  1024. unsigned int unwanted = len1 % itr->alignment;
  1025. len1 -= unwanted;
  1026. size -= unwanted;
  1027. }
  1028. /* padding must be written by fn() e.g. record__process_auxtrace() */
  1029. padding = size & (PERF_AUXTRACE_RECORD_ALIGNMENT - 1);
  1030. if (padding)
  1031. padding = PERF_AUXTRACE_RECORD_ALIGNMENT - padding;
  1032. memset(&ev, 0, sizeof(ev));
  1033. ev.auxtrace.header.type = PERF_RECORD_AUXTRACE;
  1034. ev.auxtrace.header.size = sizeof(ev.auxtrace);
  1035. ev.auxtrace.size = size + padding;
  1036. ev.auxtrace.offset = offset;
  1037. ev.auxtrace.reference = ref;
  1038. ev.auxtrace.idx = mm->idx;
  1039. ev.auxtrace.tid = mm->tid;
  1040. ev.auxtrace.cpu = mm->cpu;
  1041. if (fn(tool, &ev, data1, len1, data2, len2))
  1042. return -1;
  1043. mm->prev = head;
  1044. if (!snapshot) {
  1045. auxtrace_mmap__write_tail(mm, head);
  1046. if (itr->read_finish) {
  1047. int err;
  1048. err = itr->read_finish(itr, mm->idx);
  1049. if (err < 0)
  1050. return err;
  1051. }
  1052. }
  1053. return 1;
  1054. }
  1055. int auxtrace_mmap__read(struct auxtrace_mmap *mm, struct auxtrace_record *itr,
  1056. struct perf_tool *tool, process_auxtrace_t fn)
  1057. {
  1058. return __auxtrace_mmap__read(mm, itr, tool, fn, false, 0);
  1059. }
  1060. int auxtrace_mmap__read_snapshot(struct auxtrace_mmap *mm,
  1061. struct auxtrace_record *itr,
  1062. struct perf_tool *tool, process_auxtrace_t fn,
  1063. size_t snapshot_size)
  1064. {
  1065. return __auxtrace_mmap__read(mm, itr, tool, fn, true, snapshot_size);
  1066. }
  1067. /**
  1068. * struct auxtrace_cache - hash table to implement a cache
  1069. * @hashtable: the hashtable
  1070. * @sz: hashtable size (number of hlists)
  1071. * @entry_size: size of an entry
  1072. * @limit: limit the number of entries to this maximum, when reached the cache
  1073. * is dropped and caching begins again with an empty cache
  1074. * @cnt: current number of entries
  1075. * @bits: hashtable size (@sz = 2^@bits)
  1076. */
  1077. struct auxtrace_cache {
  1078. struct hlist_head *hashtable;
  1079. size_t sz;
  1080. size_t entry_size;
  1081. size_t limit;
  1082. size_t cnt;
  1083. unsigned int bits;
  1084. };
  1085. struct auxtrace_cache *auxtrace_cache__new(unsigned int bits, size_t entry_size,
  1086. unsigned int limit_percent)
  1087. {
  1088. struct auxtrace_cache *c;
  1089. struct hlist_head *ht;
  1090. size_t sz, i;
  1091. c = zalloc(sizeof(struct auxtrace_cache));
  1092. if (!c)
  1093. return NULL;
  1094. sz = 1UL << bits;
  1095. ht = calloc(sz, sizeof(struct hlist_head));
  1096. if (!ht)
  1097. goto out_free;
  1098. for (i = 0; i < sz; i++)
  1099. INIT_HLIST_HEAD(&ht[i]);
  1100. c->hashtable = ht;
  1101. c->sz = sz;
  1102. c->entry_size = entry_size;
  1103. c->limit = (c->sz * limit_percent) / 100;
  1104. c->bits = bits;
  1105. return c;
  1106. out_free:
  1107. free(c);
  1108. return NULL;
  1109. }
  1110. static void auxtrace_cache__drop(struct auxtrace_cache *c)
  1111. {
  1112. struct auxtrace_cache_entry *entry;
  1113. struct hlist_node *tmp;
  1114. size_t i;
  1115. if (!c)
  1116. return;
  1117. for (i = 0; i < c->sz; i++) {
  1118. hlist_for_each_entry_safe(entry, tmp, &c->hashtable[i], hash) {
  1119. hlist_del(&entry->hash);
  1120. auxtrace_cache__free_entry(c, entry);
  1121. }
  1122. }
  1123. c->cnt = 0;
  1124. }
  1125. void auxtrace_cache__free(struct auxtrace_cache *c)
  1126. {
  1127. if (!c)
  1128. return;
  1129. auxtrace_cache__drop(c);
  1130. free(c->hashtable);
  1131. free(c);
  1132. }
  1133. void *auxtrace_cache__alloc_entry(struct auxtrace_cache *c)
  1134. {
  1135. return malloc(c->entry_size);
  1136. }
  1137. void auxtrace_cache__free_entry(struct auxtrace_cache *c __maybe_unused,
  1138. void *entry)
  1139. {
  1140. free(entry);
  1141. }
  1142. int auxtrace_cache__add(struct auxtrace_cache *c, u32 key,
  1143. struct auxtrace_cache_entry *entry)
  1144. {
  1145. if (c->limit && ++c->cnt > c->limit)
  1146. auxtrace_cache__drop(c);
  1147. entry->key = key;
  1148. hlist_add_head(&entry->hash, &c->hashtable[hash_32(key, c->bits)]);
  1149. return 0;
  1150. }
  1151. void *auxtrace_cache__lookup(struct auxtrace_cache *c, u32 key)
  1152. {
  1153. struct auxtrace_cache_entry *entry;
  1154. struct hlist_head *hlist;
  1155. if (!c)
  1156. return NULL;
  1157. hlist = &c->hashtable[hash_32(key, c->bits)];
  1158. hlist_for_each_entry(entry, hlist, hash) {
  1159. if (entry->key == key)
  1160. return entry;
  1161. }
  1162. return NULL;
  1163. }