builtin-top.c 17 KB

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  1. /*
  2. * builtin-top.c
  3. *
  4. * Builtin top command: Display a continuously updated profile of
  5. * any workload, CPU or specific PID.
  6. *
  7. * Copyright (C) 2008, Red Hat Inc, Ingo Molnar <mingo@redhat.com>
  8. *
  9. * Improvements and fixes by:
  10. *
  11. * Arjan van de Ven <arjan@linux.intel.com>
  12. * Yanmin Zhang <yanmin.zhang@intel.com>
  13. * Wu Fengguang <fengguang.wu@intel.com>
  14. * Mike Galbraith <efault@gmx.de>
  15. * Paul Mackerras <paulus@samba.org>
  16. *
  17. * Released under the GPL v2. (and only v2, not any later version)
  18. */
  19. #include "builtin.h"
  20. #include "perf.h"
  21. #include "util/symbol.h"
  22. #include "util/color.h"
  23. #include "util/util.h"
  24. #include "util/rbtree.h"
  25. #include "util/parse-options.h"
  26. #include "util/parse-events.h"
  27. #include <assert.h>
  28. #include <fcntl.h>
  29. #include <stdio.h>
  30. #include <errno.h>
  31. #include <time.h>
  32. #include <sched.h>
  33. #include <pthread.h>
  34. #include <sys/syscall.h>
  35. #include <sys/ioctl.h>
  36. #include <sys/poll.h>
  37. #include <sys/prctl.h>
  38. #include <sys/wait.h>
  39. #include <sys/uio.h>
  40. #include <sys/mman.h>
  41. #include <linux/unistd.h>
  42. #include <linux/types.h>
  43. static int fd[MAX_NR_CPUS][MAX_COUNTERS];
  44. static int system_wide = 0;
  45. static int default_interval = 100000;
  46. static u64 count_filter = 5;
  47. static int print_entries = 15;
  48. static int target_pid = -1;
  49. static int profile_cpu = -1;
  50. static int nr_cpus = 0;
  51. static unsigned int realtime_prio = 0;
  52. static int group = 0;
  53. static unsigned int page_size;
  54. static unsigned int mmap_pages = 16;
  55. static int freq = 0;
  56. static int verbose = 0;
  57. static char *sym_filter;
  58. static unsigned long filter_start;
  59. static unsigned long filter_end;
  60. static int delay_secs = 2;
  61. static int zero;
  62. static int dump_symtab;
  63. /*
  64. * Symbols
  65. */
  66. static u64 min_ip;
  67. static u64 max_ip = -1ll;
  68. struct sym_entry {
  69. struct rb_node rb_node;
  70. struct list_head node;
  71. unsigned long count[MAX_COUNTERS];
  72. unsigned long snap_count;
  73. double weight;
  74. int skip;
  75. };
  76. struct sym_entry *sym_filter_entry;
  77. struct dso *kernel_dso;
  78. /*
  79. * Symbols will be added here in record_ip and will get out
  80. * after decayed.
  81. */
  82. static LIST_HEAD(active_symbols);
  83. static pthread_mutex_t active_symbols_lock = PTHREAD_MUTEX_INITIALIZER;
  84. /*
  85. * Ordering weight: count-1 * count-2 * ... / count-n
  86. */
  87. static double sym_weight(const struct sym_entry *sym)
  88. {
  89. double weight = sym->snap_count;
  90. int counter;
  91. for (counter = 1; counter < nr_counters-1; counter++)
  92. weight *= sym->count[counter];
  93. weight /= (sym->count[counter] + 1);
  94. return weight;
  95. }
  96. static long samples;
  97. static long userspace_samples;
  98. static const char CONSOLE_CLEAR[] = "";
  99. static void __list_insert_active_sym(struct sym_entry *syme)
  100. {
  101. list_add(&syme->node, &active_symbols);
  102. }
  103. static void list_remove_active_sym(struct sym_entry *syme)
  104. {
  105. pthread_mutex_lock(&active_symbols_lock);
  106. list_del_init(&syme->node);
  107. pthread_mutex_unlock(&active_symbols_lock);
  108. }
  109. static void rb_insert_active_sym(struct rb_root *tree, struct sym_entry *se)
  110. {
  111. struct rb_node **p = &tree->rb_node;
  112. struct rb_node *parent = NULL;
  113. struct sym_entry *iter;
  114. while (*p != NULL) {
  115. parent = *p;
  116. iter = rb_entry(parent, struct sym_entry, rb_node);
  117. if (se->weight > iter->weight)
  118. p = &(*p)->rb_left;
  119. else
  120. p = &(*p)->rb_right;
  121. }
  122. rb_link_node(&se->rb_node, parent, p);
  123. rb_insert_color(&se->rb_node, tree);
  124. }
  125. static void print_sym_table(void)
  126. {
  127. int printed = 0, j;
  128. int counter;
  129. float samples_per_sec = samples/delay_secs;
  130. float ksamples_per_sec = (samples-userspace_samples)/delay_secs;
  131. float sum_ksamples = 0.0;
  132. struct sym_entry *syme, *n;
  133. struct rb_root tmp = RB_ROOT;
  134. struct rb_node *nd;
  135. samples = userspace_samples = 0;
  136. /* Sort the active symbols */
  137. pthread_mutex_lock(&active_symbols_lock);
  138. syme = list_entry(active_symbols.next, struct sym_entry, node);
  139. pthread_mutex_unlock(&active_symbols_lock);
  140. list_for_each_entry_safe_from(syme, n, &active_symbols, node) {
  141. syme->snap_count = syme->count[0];
  142. if (syme->snap_count != 0) {
  143. syme->weight = sym_weight(syme);
  144. rb_insert_active_sym(&tmp, syme);
  145. sum_ksamples += syme->snap_count;
  146. for (j = 0; j < nr_counters; j++)
  147. syme->count[j] = zero ? 0 : syme->count[j] * 7 / 8;
  148. } else
  149. list_remove_active_sym(syme);
  150. }
  151. puts(CONSOLE_CLEAR);
  152. printf(
  153. "------------------------------------------------------------------------------\n");
  154. printf( " PerfTop:%8.0f irqs/sec kernel:%4.1f%% [",
  155. samples_per_sec,
  156. 100.0 - (100.0*((samples_per_sec-ksamples_per_sec)/samples_per_sec)));
  157. if (nr_counters == 1) {
  158. printf("%Ld", (u64)attrs[0].sample_period);
  159. if (freq)
  160. printf("Hz ");
  161. else
  162. printf(" ");
  163. }
  164. for (counter = 0; counter < nr_counters; counter++) {
  165. if (counter)
  166. printf("/");
  167. printf("%s", event_name(counter));
  168. }
  169. printf( "], ");
  170. if (target_pid != -1)
  171. printf(" (target_pid: %d", target_pid);
  172. else
  173. printf(" (all");
  174. if (profile_cpu != -1)
  175. printf(", cpu: %d)\n", profile_cpu);
  176. else {
  177. if (target_pid != -1)
  178. printf(")\n");
  179. else
  180. printf(", %d CPUs)\n", nr_cpus);
  181. }
  182. printf("------------------------------------------------------------------------------\n\n");
  183. if (nr_counters == 1)
  184. printf(" samples pcnt");
  185. else
  186. printf(" weight samples pcnt");
  187. printf(" RIP kernel function\n"
  188. " ______ _______ _____ ________________ _______________\n\n"
  189. );
  190. for (nd = rb_first(&tmp); nd; nd = rb_next(nd)) {
  191. struct sym_entry *syme = rb_entry(nd, struct sym_entry, rb_node);
  192. struct symbol *sym = (struct symbol *)(syme + 1);
  193. char *color = PERF_COLOR_NORMAL;
  194. double pcnt;
  195. if (++printed > print_entries || syme->snap_count < count_filter)
  196. continue;
  197. pcnt = 100.0 - (100.0 * ((sum_ksamples - syme->snap_count) /
  198. sum_ksamples));
  199. /*
  200. * We color high-overhead entries in red, mid-overhead
  201. * entries in green - and keep the low overhead places
  202. * normal:
  203. */
  204. if (pcnt >= 5.0) {
  205. color = PERF_COLOR_RED;
  206. } else {
  207. if (pcnt >= 0.5)
  208. color = PERF_COLOR_GREEN;
  209. }
  210. if (nr_counters == 1)
  211. printf("%20.2f - ", syme->weight);
  212. else
  213. printf("%9.1f %10ld - ", syme->weight, syme->snap_count);
  214. color_fprintf(stdout, color, "%4.1f%%", pcnt);
  215. printf(" - %016llx : %s\n", sym->start, sym->name);
  216. }
  217. }
  218. static void *display_thread(void *arg)
  219. {
  220. struct pollfd stdin_poll = { .fd = 0, .events = POLLIN };
  221. int delay_msecs = delay_secs * 1000;
  222. printf("PerfTop refresh period: %d seconds\n", delay_secs);
  223. do {
  224. print_sym_table();
  225. } while (!poll(&stdin_poll, 1, delay_msecs) == 1);
  226. printf("key pressed - exiting.\n");
  227. exit(0);
  228. return NULL;
  229. }
  230. /* Tag samples to be skipped. */
  231. char *skip_symbols[] = {
  232. "default_idle",
  233. "cpu_idle",
  234. "enter_idle",
  235. "exit_idle",
  236. "mwait_idle",
  237. NULL
  238. };
  239. static int symbol_filter(struct dso *self, struct symbol *sym)
  240. {
  241. static int filter_match;
  242. struct sym_entry *syme;
  243. const char *name = sym->name;
  244. int i;
  245. if (!strcmp(name, "_text") ||
  246. !strcmp(name, "_etext") ||
  247. !strcmp(name, "_sinittext") ||
  248. !strncmp("init_module", name, 11) ||
  249. !strncmp("cleanup_module", name, 14) ||
  250. strstr(name, "_text_start") ||
  251. strstr(name, "_text_end"))
  252. return 1;
  253. syme = dso__sym_priv(self, sym);
  254. for (i = 0; skip_symbols[i]; i++) {
  255. if (!strcmp(skip_symbols[i], name)) {
  256. syme->skip = 1;
  257. break;
  258. }
  259. }
  260. if (filter_match == 1) {
  261. filter_end = sym->start;
  262. filter_match = -1;
  263. if (filter_end - filter_start > 10000) {
  264. fprintf(stderr,
  265. "hm, too large filter symbol <%s> - skipping.\n",
  266. sym_filter);
  267. fprintf(stderr, "symbol filter start: %016lx\n",
  268. filter_start);
  269. fprintf(stderr, " end: %016lx\n",
  270. filter_end);
  271. filter_end = filter_start = 0;
  272. sym_filter = NULL;
  273. sleep(1);
  274. }
  275. }
  276. if (filter_match == 0 && sym_filter && !strcmp(name, sym_filter)) {
  277. filter_match = 1;
  278. filter_start = sym->start;
  279. }
  280. return 0;
  281. }
  282. static int parse_symbols(void)
  283. {
  284. struct rb_node *node;
  285. struct symbol *sym;
  286. kernel_dso = dso__new("[kernel]", sizeof(struct sym_entry));
  287. if (kernel_dso == NULL)
  288. return -1;
  289. if (dso__load_kernel(kernel_dso, NULL, symbol_filter, 1) != 0)
  290. goto out_delete_dso;
  291. node = rb_first(&kernel_dso->syms);
  292. sym = rb_entry(node, struct symbol, rb_node);
  293. min_ip = sym->start;
  294. node = rb_last(&kernel_dso->syms);
  295. sym = rb_entry(node, struct symbol, rb_node);
  296. max_ip = sym->end;
  297. if (dump_symtab)
  298. dso__fprintf(kernel_dso, stderr);
  299. return 0;
  300. out_delete_dso:
  301. dso__delete(kernel_dso);
  302. kernel_dso = NULL;
  303. return -1;
  304. }
  305. #define TRACE_COUNT 3
  306. /*
  307. * Binary search in the histogram table and record the hit:
  308. */
  309. static void record_ip(u64 ip, int counter)
  310. {
  311. struct symbol *sym = dso__find_symbol(kernel_dso, ip);
  312. if (sym != NULL) {
  313. struct sym_entry *syme = dso__sym_priv(kernel_dso, sym);
  314. if (!syme->skip) {
  315. syme->count[counter]++;
  316. pthread_mutex_lock(&active_symbols_lock);
  317. if (list_empty(&syme->node) || !syme->node.next)
  318. __list_insert_active_sym(syme);
  319. pthread_mutex_unlock(&active_symbols_lock);
  320. return;
  321. }
  322. }
  323. samples--;
  324. }
  325. static void process_event(u64 ip, int counter, int user)
  326. {
  327. samples++;
  328. if (user) {
  329. userspace_samples++;
  330. return;
  331. }
  332. record_ip(ip, counter);
  333. }
  334. struct mmap_data {
  335. int counter;
  336. void *base;
  337. unsigned int mask;
  338. unsigned int prev;
  339. };
  340. static unsigned int mmap_read_head(struct mmap_data *md)
  341. {
  342. struct perf_counter_mmap_page *pc = md->base;
  343. int head;
  344. head = pc->data_head;
  345. rmb();
  346. return head;
  347. }
  348. struct timeval last_read, this_read;
  349. static void mmap_read_counter(struct mmap_data *md)
  350. {
  351. unsigned int head = mmap_read_head(md);
  352. unsigned int old = md->prev;
  353. unsigned char *data = md->base + page_size;
  354. int diff;
  355. gettimeofday(&this_read, NULL);
  356. /*
  357. * If we're further behind than half the buffer, there's a chance
  358. * the writer will bite our tail and mess up the samples under us.
  359. *
  360. * If we somehow ended up ahead of the head, we got messed up.
  361. *
  362. * In either case, truncate and restart at head.
  363. */
  364. diff = head - old;
  365. if (diff > md->mask / 2 || diff < 0) {
  366. struct timeval iv;
  367. unsigned long msecs;
  368. timersub(&this_read, &last_read, &iv);
  369. msecs = iv.tv_sec*1000 + iv.tv_usec/1000;
  370. fprintf(stderr, "WARNING: failed to keep up with mmap data."
  371. " Last read %lu msecs ago.\n", msecs);
  372. /*
  373. * head points to a known good entry, start there.
  374. */
  375. old = head;
  376. }
  377. last_read = this_read;
  378. for (; old != head;) {
  379. struct ip_event {
  380. struct perf_event_header header;
  381. u64 ip;
  382. u32 pid, target_pid;
  383. };
  384. struct mmap_event {
  385. struct perf_event_header header;
  386. u32 pid, target_pid;
  387. u64 start;
  388. u64 len;
  389. u64 pgoff;
  390. char filename[PATH_MAX];
  391. };
  392. typedef union event_union {
  393. struct perf_event_header header;
  394. struct ip_event ip;
  395. struct mmap_event mmap;
  396. } event_t;
  397. event_t *event = (event_t *)&data[old & md->mask];
  398. event_t event_copy;
  399. size_t size = event->header.size;
  400. /*
  401. * Event straddles the mmap boundary -- header should always
  402. * be inside due to u64 alignment of output.
  403. */
  404. if ((old & md->mask) + size != ((old + size) & md->mask)) {
  405. unsigned int offset = old;
  406. unsigned int len = min(sizeof(*event), size), cpy;
  407. void *dst = &event_copy;
  408. do {
  409. cpy = min(md->mask + 1 - (offset & md->mask), len);
  410. memcpy(dst, &data[offset & md->mask], cpy);
  411. offset += cpy;
  412. dst += cpy;
  413. len -= cpy;
  414. } while (len);
  415. event = &event_copy;
  416. }
  417. old += size;
  418. if (event->header.type == PERF_EVENT_SAMPLE) {
  419. int user =
  420. (event->header.misc & PERF_EVENT_MISC_CPUMODE_MASK) == PERF_EVENT_MISC_USER;
  421. process_event(event->ip.ip, md->counter, user);
  422. }
  423. }
  424. md->prev = old;
  425. }
  426. static struct pollfd event_array[MAX_NR_CPUS * MAX_COUNTERS];
  427. static struct mmap_data mmap_array[MAX_NR_CPUS][MAX_COUNTERS];
  428. static void mmap_read(void)
  429. {
  430. int i, counter;
  431. for (i = 0; i < nr_cpus; i++) {
  432. for (counter = 0; counter < nr_counters; counter++)
  433. mmap_read_counter(&mmap_array[i][counter]);
  434. }
  435. }
  436. int nr_poll;
  437. int group_fd;
  438. static void start_counter(int i, int counter)
  439. {
  440. struct perf_counter_attr *attr;
  441. unsigned int cpu;
  442. cpu = profile_cpu;
  443. if (target_pid == -1 && profile_cpu == -1)
  444. cpu = i;
  445. attr = attrs + counter;
  446. attr->sample_type = PERF_SAMPLE_IP | PERF_SAMPLE_TID;
  447. attr->freq = freq;
  448. try_again:
  449. fd[i][counter] = sys_perf_counter_open(attr, target_pid, cpu, group_fd, 0);
  450. if (fd[i][counter] < 0) {
  451. int err = errno;
  452. if (err == EPERM)
  453. die("No permission - are you root?\n");
  454. /*
  455. * If it's cycles then fall back to hrtimer
  456. * based cpu-clock-tick sw counter, which
  457. * is always available even if no PMU support:
  458. */
  459. if (attr->type == PERF_TYPE_HARDWARE
  460. && attr->config == PERF_COUNT_HW_CPU_CYCLES) {
  461. if (verbose)
  462. warning(" ... trying to fall back to cpu-clock-ticks\n");
  463. attr->type = PERF_TYPE_SOFTWARE;
  464. attr->config = PERF_COUNT_SW_CPU_CLOCK;
  465. goto try_again;
  466. }
  467. printf("\n");
  468. error("perfcounter syscall returned with %d (%s)\n",
  469. fd[i][counter], strerror(err));
  470. die("No CONFIG_PERF_COUNTERS=y kernel support configured?\n");
  471. exit(-1);
  472. }
  473. assert(fd[i][counter] >= 0);
  474. fcntl(fd[i][counter], F_SETFL, O_NONBLOCK);
  475. /*
  476. * First counter acts as the group leader:
  477. */
  478. if (group && group_fd == -1)
  479. group_fd = fd[i][counter];
  480. event_array[nr_poll].fd = fd[i][counter];
  481. event_array[nr_poll].events = POLLIN;
  482. nr_poll++;
  483. mmap_array[i][counter].counter = counter;
  484. mmap_array[i][counter].prev = 0;
  485. mmap_array[i][counter].mask = mmap_pages*page_size - 1;
  486. mmap_array[i][counter].base = mmap(NULL, (mmap_pages+1)*page_size,
  487. PROT_READ, MAP_SHARED, fd[i][counter], 0);
  488. if (mmap_array[i][counter].base == MAP_FAILED)
  489. die("failed to mmap with %d (%s)\n", errno, strerror(errno));
  490. }
  491. static int __cmd_top(void)
  492. {
  493. pthread_t thread;
  494. int i, counter;
  495. int ret;
  496. for (i = 0; i < nr_cpus; i++) {
  497. group_fd = -1;
  498. for (counter = 0; counter < nr_counters; counter++)
  499. start_counter(i, counter);
  500. }
  501. /* Wait for a minimal set of events before starting the snapshot */
  502. poll(event_array, nr_poll, 100);
  503. mmap_read();
  504. if (pthread_create(&thread, NULL, display_thread, NULL)) {
  505. printf("Could not create display thread.\n");
  506. exit(-1);
  507. }
  508. if (realtime_prio) {
  509. struct sched_param param;
  510. param.sched_priority = realtime_prio;
  511. if (sched_setscheduler(0, SCHED_FIFO, &param)) {
  512. printf("Could not set realtime priority.\n");
  513. exit(-1);
  514. }
  515. }
  516. while (1) {
  517. int hits = samples;
  518. mmap_read();
  519. if (hits == samples)
  520. ret = poll(event_array, nr_poll, 100);
  521. }
  522. return 0;
  523. }
  524. static const char * const top_usage[] = {
  525. "perf top [<options>]",
  526. NULL
  527. };
  528. static const struct option options[] = {
  529. OPT_CALLBACK('e', "event", NULL, "event",
  530. "event selector. use 'perf list' to list available events",
  531. parse_events),
  532. OPT_INTEGER('c', "count", &default_interval,
  533. "event period to sample"),
  534. OPT_INTEGER('p', "pid", &target_pid,
  535. "profile events on existing pid"),
  536. OPT_BOOLEAN('a', "all-cpus", &system_wide,
  537. "system-wide collection from all CPUs"),
  538. OPT_INTEGER('C', "CPU", &profile_cpu,
  539. "CPU to profile on"),
  540. OPT_INTEGER('m', "mmap-pages", &mmap_pages,
  541. "number of mmap data pages"),
  542. OPT_INTEGER('r', "realtime", &realtime_prio,
  543. "collect data with this RT SCHED_FIFO priority"),
  544. OPT_INTEGER('d', "delay", &delay_secs,
  545. "number of seconds to delay between refreshes"),
  546. OPT_BOOLEAN('D', "dump-symtab", &dump_symtab,
  547. "dump the symbol table used for profiling"),
  548. OPT_INTEGER('f', "count-filter", &count_filter,
  549. "only display functions with more events than this"),
  550. OPT_BOOLEAN('g', "group", &group,
  551. "put the counters into a counter group"),
  552. OPT_STRING('s', "sym-filter", &sym_filter, "pattern",
  553. "only display symbols matchig this pattern"),
  554. OPT_BOOLEAN('z', "zero", &zero,
  555. "zero history across updates"),
  556. OPT_INTEGER('F', "freq", &freq,
  557. "profile at this frequency"),
  558. OPT_INTEGER('E', "entries", &print_entries,
  559. "display this many functions"),
  560. OPT_BOOLEAN('v', "verbose", &verbose,
  561. "be more verbose (show counter open errors, etc)"),
  562. OPT_END()
  563. };
  564. int cmd_top(int argc, const char **argv, const char *prefix)
  565. {
  566. int counter;
  567. page_size = sysconf(_SC_PAGE_SIZE);
  568. argc = parse_options(argc, argv, options, top_usage, 0);
  569. if (argc)
  570. usage_with_options(top_usage, options);
  571. if (freq) {
  572. default_interval = freq;
  573. freq = 1;
  574. }
  575. /* CPU and PID are mutually exclusive */
  576. if (target_pid != -1 && profile_cpu != -1) {
  577. printf("WARNING: PID switch overriding CPU\n");
  578. sleep(1);
  579. profile_cpu = -1;
  580. }
  581. if (!nr_counters)
  582. nr_counters = 1;
  583. if (delay_secs < 1)
  584. delay_secs = 1;
  585. parse_symbols();
  586. /*
  587. * Fill in the ones not specifically initialized via -c:
  588. */
  589. for (counter = 0; counter < nr_counters; counter++) {
  590. if (attrs[counter].sample_period)
  591. continue;
  592. attrs[counter].sample_period = default_interval;
  593. }
  594. nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
  595. assert(nr_cpus <= MAX_NR_CPUS);
  596. assert(nr_cpus >= 0);
  597. if (target_pid != -1 || profile_cpu != -1)
  598. nr_cpus = 1;
  599. return __cmd_top();
  600. }