trace_output.c 25 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490491492493494495496497498499500501502503504505506507508509510511512513514515516517518519520521522523524525526527528529530531532533534535536537538539540541542543544545546547548549550551552553554555556557558559560561562563564565566567568569570571572573574575576577578579580581582583584585586587588589590591592593594595596597598599600601602603604605606607608609610611612613614615616617618619620621622623624625626627628629630631632633634635636637638639640641642643644645646647648649650651652653654655656657658659660661662663664665666667668669670671672673674675676677678679680681682683684685686687688689690691692693694695696697698699700701702703704705706707708709710711712713714715716717718719720721722723724725726727728729730731732733734735736737738739740741742743744745746747748749750751752753754755756757758759760761762763764765766767768769770771772773774775776777778779780781782783784785786787788789790791792793794795796797798799800801802803804805806807808809810811812813814815816817818819820821822823824825826827828829830831832833834835836837838839840841842843844845846847848849850851852853854855856857858859860861862863864865866867868869870871872873874875876877878879880881882883884885886887888889890891892893894895896897898899900901902903904905906907908909910911912913914915916917918919920921922923924925926927928929930931932933934935936937938939940941942943944945946947948949950951952953954955956957958959960961962963964965966967968969970971972973974975976977978979980981982983984985986987988989990991992993994995996997998999100010011002100310041005100610071008100910101011101210131014101510161017101810191020102110221023102410251026102710281029103010311032103310341035103610371038103910401041104210431044104510461047104810491050105110521053105410551056105710581059106010611062106310641065106610671068106910701071107210731074107510761077107810791080108110821083108410851086108710881089109010911092109310941095109610971098109911001101110211031104110511061107110811091110111111121113111411151116111711181119112011211122112311241125112611271128112911301131113211331134113511361137113811391140114111421143114411451146114711481149115011511152115311541155115611571158115911601161116211631164116511661167116811691170117111721173117411751176117711781179118011811182118311841185118611871188118911901191119211931194119511961197119811991200120112021203
  1. /*
  2. * trace_output.c
  3. *
  4. * Copyright (C) 2008 Red Hat Inc, Steven Rostedt <srostedt@redhat.com>
  5. *
  6. */
  7. #include <linux/module.h>
  8. #include <linux/mutex.h>
  9. #include <linux/ftrace.h>
  10. #include "trace_output.h"
  11. /* must be a power of 2 */
  12. #define EVENT_HASHSIZE 128
  13. DECLARE_RWSEM(trace_event_mutex);
  14. DEFINE_PER_CPU(struct trace_seq, ftrace_event_seq);
  15. EXPORT_PER_CPU_SYMBOL(ftrace_event_seq);
  16. static struct hlist_head event_hash[EVENT_HASHSIZE] __read_mostly;
  17. static int next_event_type = __TRACE_LAST_TYPE + 1;
  18. void trace_print_seq(struct seq_file *m, struct trace_seq *s)
  19. {
  20. int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len;
  21. s->buffer[len] = 0;
  22. seq_puts(m, s->buffer);
  23. trace_seq_init(s);
  24. }
  25. enum print_line_t trace_print_bprintk_msg_only(struct trace_iterator *iter)
  26. {
  27. struct trace_seq *s = &iter->seq;
  28. struct trace_entry *entry = iter->ent;
  29. struct bprint_entry *field;
  30. int ret;
  31. trace_assign_type(field, entry);
  32. ret = trace_seq_bprintf(s, field->fmt, field->buf);
  33. if (!ret)
  34. return TRACE_TYPE_PARTIAL_LINE;
  35. return TRACE_TYPE_HANDLED;
  36. }
  37. enum print_line_t trace_print_printk_msg_only(struct trace_iterator *iter)
  38. {
  39. struct trace_seq *s = &iter->seq;
  40. struct trace_entry *entry = iter->ent;
  41. struct print_entry *field;
  42. int ret;
  43. trace_assign_type(field, entry);
  44. ret = trace_seq_printf(s, "%s", field->buf);
  45. if (!ret)
  46. return TRACE_TYPE_PARTIAL_LINE;
  47. return TRACE_TYPE_HANDLED;
  48. }
  49. /**
  50. * trace_seq_printf - sequence printing of trace information
  51. * @s: trace sequence descriptor
  52. * @fmt: printf format string
  53. *
  54. * The tracer may use either sequence operations or its own
  55. * copy to user routines. To simplify formating of a trace
  56. * trace_seq_printf is used to store strings into a special
  57. * buffer (@s). Then the output may be either used by
  58. * the sequencer or pulled into another buffer.
  59. */
  60. int
  61. trace_seq_printf(struct trace_seq *s, const char *fmt, ...)
  62. {
  63. int len = (PAGE_SIZE - 1) - s->len;
  64. va_list ap;
  65. int ret;
  66. if (!len)
  67. return 0;
  68. va_start(ap, fmt);
  69. ret = vsnprintf(s->buffer + s->len, len, fmt, ap);
  70. va_end(ap);
  71. /* If we can't write it all, don't bother writing anything */
  72. if (ret >= len)
  73. return 0;
  74. s->len += ret;
  75. return len;
  76. }
  77. EXPORT_SYMBOL_GPL(trace_seq_printf);
  78. /**
  79. * trace_seq_vprintf - sequence printing of trace information
  80. * @s: trace sequence descriptor
  81. * @fmt: printf format string
  82. *
  83. * The tracer may use either sequence operations or its own
  84. * copy to user routines. To simplify formating of a trace
  85. * trace_seq_printf is used to store strings into a special
  86. * buffer (@s). Then the output may be either used by
  87. * the sequencer or pulled into another buffer.
  88. */
  89. int
  90. trace_seq_vprintf(struct trace_seq *s, const char *fmt, va_list args)
  91. {
  92. int len = (PAGE_SIZE - 1) - s->len;
  93. int ret;
  94. if (!len)
  95. return 0;
  96. ret = vsnprintf(s->buffer + s->len, len, fmt, args);
  97. /* If we can't write it all, don't bother writing anything */
  98. if (ret >= len)
  99. return 0;
  100. s->len += ret;
  101. return len;
  102. }
  103. EXPORT_SYMBOL_GPL(trace_seq_vprintf);
  104. int trace_seq_bprintf(struct trace_seq *s, const char *fmt, const u32 *binary)
  105. {
  106. int len = (PAGE_SIZE - 1) - s->len;
  107. int ret;
  108. if (!len)
  109. return 0;
  110. ret = bstr_printf(s->buffer + s->len, len, fmt, binary);
  111. /* If we can't write it all, don't bother writing anything */
  112. if (ret >= len)
  113. return 0;
  114. s->len += ret;
  115. return len;
  116. }
  117. /**
  118. * trace_seq_puts - trace sequence printing of simple string
  119. * @s: trace sequence descriptor
  120. * @str: simple string to record
  121. *
  122. * The tracer may use either the sequence operations or its own
  123. * copy to user routines. This function records a simple string
  124. * into a special buffer (@s) for later retrieval by a sequencer
  125. * or other mechanism.
  126. */
  127. int trace_seq_puts(struct trace_seq *s, const char *str)
  128. {
  129. int len = strlen(str);
  130. if (len > ((PAGE_SIZE - 1) - s->len))
  131. return 0;
  132. memcpy(s->buffer + s->len, str, len);
  133. s->len += len;
  134. return len;
  135. }
  136. int trace_seq_putc(struct trace_seq *s, unsigned char c)
  137. {
  138. if (s->len >= (PAGE_SIZE - 1))
  139. return 0;
  140. s->buffer[s->len++] = c;
  141. return 1;
  142. }
  143. int trace_seq_putmem(struct trace_seq *s, const void *mem, size_t len)
  144. {
  145. if (len > ((PAGE_SIZE - 1) - s->len))
  146. return 0;
  147. memcpy(s->buffer + s->len, mem, len);
  148. s->len += len;
  149. return len;
  150. }
  151. int trace_seq_putmem_hex(struct trace_seq *s, const void *mem, size_t len)
  152. {
  153. unsigned char hex[HEX_CHARS];
  154. const unsigned char *data = mem;
  155. int i, j;
  156. #ifdef __BIG_ENDIAN
  157. for (i = 0, j = 0; i < len; i++) {
  158. #else
  159. for (i = len-1, j = 0; i >= 0; i--) {
  160. #endif
  161. hex[j++] = hex_asc_hi(data[i]);
  162. hex[j++] = hex_asc_lo(data[i]);
  163. }
  164. hex[j++] = ' ';
  165. return trace_seq_putmem(s, hex, j);
  166. }
  167. void *trace_seq_reserve(struct trace_seq *s, size_t len)
  168. {
  169. void *ret;
  170. if (len > ((PAGE_SIZE - 1) - s->len))
  171. return NULL;
  172. ret = s->buffer + s->len;
  173. s->len += len;
  174. return ret;
  175. }
  176. int trace_seq_path(struct trace_seq *s, struct path *path)
  177. {
  178. unsigned char *p;
  179. if (s->len >= (PAGE_SIZE - 1))
  180. return 0;
  181. p = d_path(path, s->buffer + s->len, PAGE_SIZE - s->len);
  182. if (!IS_ERR(p)) {
  183. p = mangle_path(s->buffer + s->len, p, "\n");
  184. if (p) {
  185. s->len = p - s->buffer;
  186. return 1;
  187. }
  188. } else {
  189. s->buffer[s->len++] = '?';
  190. return 1;
  191. }
  192. return 0;
  193. }
  194. const char *
  195. ftrace_print_flags_seq(struct trace_seq *p, const char *delim,
  196. unsigned long flags,
  197. const struct trace_print_flags *flag_array)
  198. {
  199. unsigned long mask;
  200. const char *str;
  201. const char *ret = p->buffer + p->len;
  202. int i;
  203. for (i = 0; flag_array[i].name && flags; i++) {
  204. mask = flag_array[i].mask;
  205. if ((flags & mask) != mask)
  206. continue;
  207. str = flag_array[i].name;
  208. flags &= ~mask;
  209. if (p->len && delim)
  210. trace_seq_puts(p, delim);
  211. trace_seq_puts(p, str);
  212. }
  213. /* check for left over flags */
  214. if (flags) {
  215. if (p->len && delim)
  216. trace_seq_puts(p, delim);
  217. trace_seq_printf(p, "0x%lx", flags);
  218. }
  219. trace_seq_putc(p, 0);
  220. return ret;
  221. }
  222. EXPORT_SYMBOL(ftrace_print_flags_seq);
  223. const char *
  224. ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val,
  225. const struct trace_print_flags *symbol_array)
  226. {
  227. int i;
  228. const char *ret = p->buffer + p->len;
  229. for (i = 0; symbol_array[i].name; i++) {
  230. if (val != symbol_array[i].mask)
  231. continue;
  232. trace_seq_puts(p, symbol_array[i].name);
  233. break;
  234. }
  235. if (!p->len)
  236. trace_seq_printf(p, "0x%lx", val);
  237. trace_seq_putc(p, 0);
  238. return ret;
  239. }
  240. EXPORT_SYMBOL(ftrace_print_symbols_seq);
  241. #ifdef CONFIG_KRETPROBES
  242. static inline const char *kretprobed(const char *name)
  243. {
  244. static const char tramp_name[] = "kretprobe_trampoline";
  245. int size = sizeof(tramp_name);
  246. if (strncmp(tramp_name, name, size) == 0)
  247. return "[unknown/kretprobe'd]";
  248. return name;
  249. }
  250. #else
  251. static inline const char *kretprobed(const char *name)
  252. {
  253. return name;
  254. }
  255. #endif /* CONFIG_KRETPROBES */
  256. static int
  257. seq_print_sym_short(struct trace_seq *s, const char *fmt, unsigned long address)
  258. {
  259. #ifdef CONFIG_KALLSYMS
  260. char str[KSYM_SYMBOL_LEN];
  261. const char *name;
  262. kallsyms_lookup(address, NULL, NULL, NULL, str);
  263. name = kretprobed(str);
  264. return trace_seq_printf(s, fmt, name);
  265. #endif
  266. return 1;
  267. }
  268. static int
  269. seq_print_sym_offset(struct trace_seq *s, const char *fmt,
  270. unsigned long address)
  271. {
  272. #ifdef CONFIG_KALLSYMS
  273. char str[KSYM_SYMBOL_LEN];
  274. const char *name;
  275. sprint_symbol(str, address);
  276. name = kretprobed(str);
  277. return trace_seq_printf(s, fmt, name);
  278. #endif
  279. return 1;
  280. }
  281. #ifndef CONFIG_64BIT
  282. # define IP_FMT "%08lx"
  283. #else
  284. # define IP_FMT "%016lx"
  285. #endif
  286. int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm,
  287. unsigned long ip, unsigned long sym_flags)
  288. {
  289. struct file *file = NULL;
  290. unsigned long vmstart = 0;
  291. int ret = 1;
  292. if (mm) {
  293. const struct vm_area_struct *vma;
  294. down_read(&mm->mmap_sem);
  295. vma = find_vma(mm, ip);
  296. if (vma) {
  297. file = vma->vm_file;
  298. vmstart = vma->vm_start;
  299. }
  300. if (file) {
  301. ret = trace_seq_path(s, &file->f_path);
  302. if (ret)
  303. ret = trace_seq_printf(s, "[+0x%lx]",
  304. ip - vmstart);
  305. }
  306. up_read(&mm->mmap_sem);
  307. }
  308. if (ret && ((sym_flags & TRACE_ITER_SYM_ADDR) || !file))
  309. ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
  310. return ret;
  311. }
  312. int
  313. seq_print_userip_objs(const struct userstack_entry *entry, struct trace_seq *s,
  314. unsigned long sym_flags)
  315. {
  316. struct mm_struct *mm = NULL;
  317. int ret = 1;
  318. unsigned int i;
  319. if (trace_flags & TRACE_ITER_SYM_USEROBJ) {
  320. struct task_struct *task;
  321. /*
  322. * we do the lookup on the thread group leader,
  323. * since individual threads might have already quit!
  324. */
  325. rcu_read_lock();
  326. task = find_task_by_vpid(entry->ent.tgid);
  327. if (task)
  328. mm = get_task_mm(task);
  329. rcu_read_unlock();
  330. }
  331. for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
  332. unsigned long ip = entry->caller[i];
  333. if (ip == ULONG_MAX || !ret)
  334. break;
  335. if (ret)
  336. ret = trace_seq_puts(s, " => ");
  337. if (!ip) {
  338. if (ret)
  339. ret = trace_seq_puts(s, "??");
  340. if (ret)
  341. ret = trace_seq_puts(s, "\n");
  342. continue;
  343. }
  344. if (!ret)
  345. break;
  346. if (ret)
  347. ret = seq_print_user_ip(s, mm, ip, sym_flags);
  348. ret = trace_seq_puts(s, "\n");
  349. }
  350. if (mm)
  351. mmput(mm);
  352. return ret;
  353. }
  354. int
  355. seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
  356. {
  357. int ret;
  358. if (!ip)
  359. return trace_seq_printf(s, "0");
  360. if (sym_flags & TRACE_ITER_SYM_OFFSET)
  361. ret = seq_print_sym_offset(s, "%s", ip);
  362. else
  363. ret = seq_print_sym_short(s, "%s", ip);
  364. if (!ret)
  365. return 0;
  366. if (sym_flags & TRACE_ITER_SYM_ADDR)
  367. ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
  368. return ret;
  369. }
  370. static int
  371. lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
  372. {
  373. int hardirq, softirq;
  374. char comm[TASK_COMM_LEN];
  375. trace_find_cmdline(entry->pid, comm);
  376. hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
  377. softirq = entry->flags & TRACE_FLAG_SOFTIRQ;
  378. if (!trace_seq_printf(s, "%8.8s-%-5d %3d%c%c%c",
  379. comm, entry->pid, cpu,
  380. (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' :
  381. (entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ?
  382. 'X' : '.',
  383. (entry->flags & TRACE_FLAG_NEED_RESCHED) ?
  384. 'N' : '.',
  385. (hardirq && softirq) ? 'H' :
  386. hardirq ? 'h' : softirq ? 's' : '.'))
  387. return 0;
  388. if (entry->preempt_count)
  389. return trace_seq_printf(s, "%x", entry->preempt_count);
  390. return trace_seq_puts(s, ".");
  391. }
  392. static unsigned long preempt_mark_thresh = 100;
  393. static int
  394. lat_print_timestamp(struct trace_seq *s, u64 abs_usecs,
  395. unsigned long rel_usecs)
  396. {
  397. return trace_seq_printf(s, " %4lldus%c: ", abs_usecs,
  398. rel_usecs > preempt_mark_thresh ? '!' :
  399. rel_usecs > 1 ? '+' : ' ');
  400. }
  401. int trace_print_context(struct trace_iterator *iter)
  402. {
  403. struct trace_seq *s = &iter->seq;
  404. struct trace_entry *entry = iter->ent;
  405. unsigned long long t = ns2usecs(iter->ts);
  406. unsigned long usec_rem = do_div(t, USEC_PER_SEC);
  407. unsigned long secs = (unsigned long)t;
  408. char comm[TASK_COMM_LEN];
  409. trace_find_cmdline(entry->pid, comm);
  410. return trace_seq_printf(s, "%16s-%-5d [%03d] %5lu.%06lu: ",
  411. comm, entry->pid, iter->cpu, secs, usec_rem);
  412. }
  413. int trace_print_lat_context(struct trace_iterator *iter)
  414. {
  415. u64 next_ts;
  416. int ret;
  417. struct trace_seq *s = &iter->seq;
  418. struct trace_entry *entry = iter->ent,
  419. *next_entry = trace_find_next_entry(iter, NULL,
  420. &next_ts);
  421. unsigned long verbose = (trace_flags & TRACE_ITER_VERBOSE);
  422. unsigned long abs_usecs = ns2usecs(iter->ts - iter->tr->time_start);
  423. unsigned long rel_usecs;
  424. if (!next_entry)
  425. next_ts = iter->ts;
  426. rel_usecs = ns2usecs(next_ts - iter->ts);
  427. if (verbose) {
  428. char comm[TASK_COMM_LEN];
  429. trace_find_cmdline(entry->pid, comm);
  430. ret = trace_seq_printf(s, "%16s %5d %3d %d %08x %08lx [%08llx]"
  431. " %ld.%03ldms (+%ld.%03ldms): ", comm,
  432. entry->pid, iter->cpu, entry->flags,
  433. entry->preempt_count, iter->idx,
  434. ns2usecs(iter->ts),
  435. abs_usecs / USEC_PER_MSEC,
  436. abs_usecs % USEC_PER_MSEC,
  437. rel_usecs / USEC_PER_MSEC,
  438. rel_usecs % USEC_PER_MSEC);
  439. } else {
  440. ret = lat_print_generic(s, entry, iter->cpu);
  441. if (ret)
  442. ret = lat_print_timestamp(s, abs_usecs, rel_usecs);
  443. }
  444. return ret;
  445. }
  446. static const char state_to_char[] = TASK_STATE_TO_CHAR_STR;
  447. static int task_state_char(unsigned long state)
  448. {
  449. int bit = state ? __ffs(state) + 1 : 0;
  450. return bit < sizeof(state_to_char) - 1 ? state_to_char[bit] : '?';
  451. }
  452. /**
  453. * ftrace_find_event - find a registered event
  454. * @type: the type of event to look for
  455. *
  456. * Returns an event of type @type otherwise NULL
  457. * Called with trace_event_read_lock() held.
  458. */
  459. struct trace_event *ftrace_find_event(int type)
  460. {
  461. struct trace_event *event;
  462. struct hlist_node *n;
  463. unsigned key;
  464. key = type & (EVENT_HASHSIZE - 1);
  465. hlist_for_each_entry(event, n, &event_hash[key], node) {
  466. if (event->type == type)
  467. return event;
  468. }
  469. return NULL;
  470. }
  471. static LIST_HEAD(ftrace_event_list);
  472. static int trace_search_list(struct list_head **list)
  473. {
  474. struct trace_event *e;
  475. int last = __TRACE_LAST_TYPE;
  476. if (list_empty(&ftrace_event_list)) {
  477. *list = &ftrace_event_list;
  478. return last + 1;
  479. }
  480. /*
  481. * We used up all possible max events,
  482. * lets see if somebody freed one.
  483. */
  484. list_for_each_entry(e, &ftrace_event_list, list) {
  485. if (e->type != last + 1)
  486. break;
  487. last++;
  488. }
  489. /* Did we used up all 65 thousand events??? */
  490. if ((last + 1) > FTRACE_MAX_EVENT)
  491. return 0;
  492. *list = &e->list;
  493. return last + 1;
  494. }
  495. void trace_event_read_lock(void)
  496. {
  497. down_read(&trace_event_mutex);
  498. }
  499. void trace_event_read_unlock(void)
  500. {
  501. up_read(&trace_event_mutex);
  502. }
  503. /**
  504. * register_ftrace_event - register output for an event type
  505. * @event: the event type to register
  506. *
  507. * Event types are stored in a hash and this hash is used to
  508. * find a way to print an event. If the @event->type is set
  509. * then it will use that type, otherwise it will assign a
  510. * type to use.
  511. *
  512. * If you assign your own type, please make sure it is added
  513. * to the trace_type enum in trace.h, to avoid collisions
  514. * with the dynamic types.
  515. *
  516. * Returns the event type number or zero on error.
  517. */
  518. int register_ftrace_event(struct trace_event *event)
  519. {
  520. unsigned key;
  521. int ret = 0;
  522. down_write(&trace_event_mutex);
  523. if (WARN_ON(!event))
  524. goto out;
  525. INIT_LIST_HEAD(&event->list);
  526. if (!event->type) {
  527. struct list_head *list = NULL;
  528. if (next_event_type > FTRACE_MAX_EVENT) {
  529. event->type = trace_search_list(&list);
  530. if (!event->type)
  531. goto out;
  532. } else {
  533. event->type = next_event_type++;
  534. list = &ftrace_event_list;
  535. }
  536. if (WARN_ON(ftrace_find_event(event->type)))
  537. goto out;
  538. list_add_tail(&event->list, list);
  539. } else if (event->type > __TRACE_LAST_TYPE) {
  540. printk(KERN_WARNING "Need to add type to trace.h\n");
  541. WARN_ON(1);
  542. goto out;
  543. } else {
  544. /* Is this event already used */
  545. if (ftrace_find_event(event->type))
  546. goto out;
  547. }
  548. if (event->trace == NULL)
  549. event->trace = trace_nop_print;
  550. if (event->raw == NULL)
  551. event->raw = trace_nop_print;
  552. if (event->hex == NULL)
  553. event->hex = trace_nop_print;
  554. if (event->binary == NULL)
  555. event->binary = trace_nop_print;
  556. key = event->type & (EVENT_HASHSIZE - 1);
  557. hlist_add_head(&event->node, &event_hash[key]);
  558. ret = event->type;
  559. out:
  560. up_write(&trace_event_mutex);
  561. return ret;
  562. }
  563. EXPORT_SYMBOL_GPL(register_ftrace_event);
  564. /*
  565. * Used by module code with the trace_event_mutex held for write.
  566. */
  567. int __unregister_ftrace_event(struct trace_event *event)
  568. {
  569. hlist_del(&event->node);
  570. list_del(&event->list);
  571. return 0;
  572. }
  573. /**
  574. * unregister_ftrace_event - remove a no longer used event
  575. * @event: the event to remove
  576. */
  577. int unregister_ftrace_event(struct trace_event *event)
  578. {
  579. down_write(&trace_event_mutex);
  580. __unregister_ftrace_event(event);
  581. up_write(&trace_event_mutex);
  582. return 0;
  583. }
  584. EXPORT_SYMBOL_GPL(unregister_ftrace_event);
  585. /*
  586. * Standard events
  587. */
  588. enum print_line_t trace_nop_print(struct trace_iterator *iter, int flags)
  589. {
  590. return TRACE_TYPE_HANDLED;
  591. }
  592. /* TRACE_FN */
  593. static enum print_line_t trace_fn_trace(struct trace_iterator *iter, int flags)
  594. {
  595. struct ftrace_entry *field;
  596. struct trace_seq *s = &iter->seq;
  597. trace_assign_type(field, iter->ent);
  598. if (!seq_print_ip_sym(s, field->ip, flags))
  599. goto partial;
  600. if ((flags & TRACE_ITER_PRINT_PARENT) && field->parent_ip) {
  601. if (!trace_seq_printf(s, " <-"))
  602. goto partial;
  603. if (!seq_print_ip_sym(s,
  604. field->parent_ip,
  605. flags))
  606. goto partial;
  607. }
  608. if (!trace_seq_printf(s, "\n"))
  609. goto partial;
  610. return TRACE_TYPE_HANDLED;
  611. partial:
  612. return TRACE_TYPE_PARTIAL_LINE;
  613. }
  614. static enum print_line_t trace_fn_raw(struct trace_iterator *iter, int flags)
  615. {
  616. struct ftrace_entry *field;
  617. trace_assign_type(field, iter->ent);
  618. if (!trace_seq_printf(&iter->seq, "%lx %lx\n",
  619. field->ip,
  620. field->parent_ip))
  621. return TRACE_TYPE_PARTIAL_LINE;
  622. return TRACE_TYPE_HANDLED;
  623. }
  624. static enum print_line_t trace_fn_hex(struct trace_iterator *iter, int flags)
  625. {
  626. struct ftrace_entry *field;
  627. struct trace_seq *s = &iter->seq;
  628. trace_assign_type(field, iter->ent);
  629. SEQ_PUT_HEX_FIELD_RET(s, field->ip);
  630. SEQ_PUT_HEX_FIELD_RET(s, field->parent_ip);
  631. return TRACE_TYPE_HANDLED;
  632. }
  633. static enum print_line_t trace_fn_bin(struct trace_iterator *iter, int flags)
  634. {
  635. struct ftrace_entry *field;
  636. struct trace_seq *s = &iter->seq;
  637. trace_assign_type(field, iter->ent);
  638. SEQ_PUT_FIELD_RET(s, field->ip);
  639. SEQ_PUT_FIELD_RET(s, field->parent_ip);
  640. return TRACE_TYPE_HANDLED;
  641. }
  642. static struct trace_event trace_fn_event = {
  643. .type = TRACE_FN,
  644. .trace = trace_fn_trace,
  645. .raw = trace_fn_raw,
  646. .hex = trace_fn_hex,
  647. .binary = trace_fn_bin,
  648. };
  649. /* TRACE_CTX an TRACE_WAKE */
  650. static enum print_line_t trace_ctxwake_print(struct trace_iterator *iter,
  651. char *delim)
  652. {
  653. struct ctx_switch_entry *field;
  654. char comm[TASK_COMM_LEN];
  655. int S, T;
  656. trace_assign_type(field, iter->ent);
  657. T = task_state_char(field->next_state);
  658. S = task_state_char(field->prev_state);
  659. trace_find_cmdline(field->next_pid, comm);
  660. if (!trace_seq_printf(&iter->seq,
  661. " %5d:%3d:%c %s [%03d] %5d:%3d:%c %s\n",
  662. field->prev_pid,
  663. field->prev_prio,
  664. S, delim,
  665. field->next_cpu,
  666. field->next_pid,
  667. field->next_prio,
  668. T, comm))
  669. return TRACE_TYPE_PARTIAL_LINE;
  670. return TRACE_TYPE_HANDLED;
  671. }
  672. static enum print_line_t trace_ctx_print(struct trace_iterator *iter, int flags)
  673. {
  674. return trace_ctxwake_print(iter, "==>");
  675. }
  676. static enum print_line_t trace_wake_print(struct trace_iterator *iter,
  677. int flags)
  678. {
  679. return trace_ctxwake_print(iter, " +");
  680. }
  681. static int trace_ctxwake_raw(struct trace_iterator *iter, char S)
  682. {
  683. struct ctx_switch_entry *field;
  684. int T;
  685. trace_assign_type(field, iter->ent);
  686. if (!S)
  687. task_state_char(field->prev_state);
  688. T = task_state_char(field->next_state);
  689. if (!trace_seq_printf(&iter->seq, "%d %d %c %d %d %d %c\n",
  690. field->prev_pid,
  691. field->prev_prio,
  692. S,
  693. field->next_cpu,
  694. field->next_pid,
  695. field->next_prio,
  696. T))
  697. return TRACE_TYPE_PARTIAL_LINE;
  698. return TRACE_TYPE_HANDLED;
  699. }
  700. static enum print_line_t trace_ctx_raw(struct trace_iterator *iter, int flags)
  701. {
  702. return trace_ctxwake_raw(iter, 0);
  703. }
  704. static enum print_line_t trace_wake_raw(struct trace_iterator *iter, int flags)
  705. {
  706. return trace_ctxwake_raw(iter, '+');
  707. }
  708. static int trace_ctxwake_hex(struct trace_iterator *iter, char S)
  709. {
  710. struct ctx_switch_entry *field;
  711. struct trace_seq *s = &iter->seq;
  712. int T;
  713. trace_assign_type(field, iter->ent);
  714. if (!S)
  715. task_state_char(field->prev_state);
  716. T = task_state_char(field->next_state);
  717. SEQ_PUT_HEX_FIELD_RET(s, field->prev_pid);
  718. SEQ_PUT_HEX_FIELD_RET(s, field->prev_prio);
  719. SEQ_PUT_HEX_FIELD_RET(s, S);
  720. SEQ_PUT_HEX_FIELD_RET(s, field->next_cpu);
  721. SEQ_PUT_HEX_FIELD_RET(s, field->next_pid);
  722. SEQ_PUT_HEX_FIELD_RET(s, field->next_prio);
  723. SEQ_PUT_HEX_FIELD_RET(s, T);
  724. return TRACE_TYPE_HANDLED;
  725. }
  726. static enum print_line_t trace_ctx_hex(struct trace_iterator *iter, int flags)
  727. {
  728. return trace_ctxwake_hex(iter, 0);
  729. }
  730. static enum print_line_t trace_wake_hex(struct trace_iterator *iter, int flags)
  731. {
  732. return trace_ctxwake_hex(iter, '+');
  733. }
  734. static enum print_line_t trace_ctxwake_bin(struct trace_iterator *iter,
  735. int flags)
  736. {
  737. struct ctx_switch_entry *field;
  738. struct trace_seq *s = &iter->seq;
  739. trace_assign_type(field, iter->ent);
  740. SEQ_PUT_FIELD_RET(s, field->prev_pid);
  741. SEQ_PUT_FIELD_RET(s, field->prev_prio);
  742. SEQ_PUT_FIELD_RET(s, field->prev_state);
  743. SEQ_PUT_FIELD_RET(s, field->next_pid);
  744. SEQ_PUT_FIELD_RET(s, field->next_prio);
  745. SEQ_PUT_FIELD_RET(s, field->next_state);
  746. return TRACE_TYPE_HANDLED;
  747. }
  748. static struct trace_event trace_ctx_event = {
  749. .type = TRACE_CTX,
  750. .trace = trace_ctx_print,
  751. .raw = trace_ctx_raw,
  752. .hex = trace_ctx_hex,
  753. .binary = trace_ctxwake_bin,
  754. };
  755. static struct trace_event trace_wake_event = {
  756. .type = TRACE_WAKE,
  757. .trace = trace_wake_print,
  758. .raw = trace_wake_raw,
  759. .hex = trace_wake_hex,
  760. .binary = trace_ctxwake_bin,
  761. };
  762. /* TRACE_SPECIAL */
  763. static enum print_line_t trace_special_print(struct trace_iterator *iter,
  764. int flags)
  765. {
  766. struct special_entry *field;
  767. trace_assign_type(field, iter->ent);
  768. if (!trace_seq_printf(&iter->seq, "# %ld %ld %ld\n",
  769. field->arg1,
  770. field->arg2,
  771. field->arg3))
  772. return TRACE_TYPE_PARTIAL_LINE;
  773. return TRACE_TYPE_HANDLED;
  774. }
  775. static enum print_line_t trace_special_hex(struct trace_iterator *iter,
  776. int flags)
  777. {
  778. struct special_entry *field;
  779. struct trace_seq *s = &iter->seq;
  780. trace_assign_type(field, iter->ent);
  781. SEQ_PUT_HEX_FIELD_RET(s, field->arg1);
  782. SEQ_PUT_HEX_FIELD_RET(s, field->arg2);
  783. SEQ_PUT_HEX_FIELD_RET(s, field->arg3);
  784. return TRACE_TYPE_HANDLED;
  785. }
  786. static enum print_line_t trace_special_bin(struct trace_iterator *iter,
  787. int flags)
  788. {
  789. struct special_entry *field;
  790. struct trace_seq *s = &iter->seq;
  791. trace_assign_type(field, iter->ent);
  792. SEQ_PUT_FIELD_RET(s, field->arg1);
  793. SEQ_PUT_FIELD_RET(s, field->arg2);
  794. SEQ_PUT_FIELD_RET(s, field->arg3);
  795. return TRACE_TYPE_HANDLED;
  796. }
  797. static struct trace_event trace_special_event = {
  798. .type = TRACE_SPECIAL,
  799. .trace = trace_special_print,
  800. .raw = trace_special_print,
  801. .hex = trace_special_hex,
  802. .binary = trace_special_bin,
  803. };
  804. /* TRACE_STACK */
  805. static enum print_line_t trace_stack_print(struct trace_iterator *iter,
  806. int flags)
  807. {
  808. struct stack_entry *field;
  809. struct trace_seq *s = &iter->seq;
  810. int i;
  811. trace_assign_type(field, iter->ent);
  812. if (!trace_seq_puts(s, "<stack trace>\n"))
  813. goto partial;
  814. for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
  815. if (!field->caller[i] || (field->caller[i] == ULONG_MAX))
  816. break;
  817. if (!trace_seq_puts(s, " => "))
  818. goto partial;
  819. if (!seq_print_ip_sym(s, field->caller[i], flags))
  820. goto partial;
  821. if (!trace_seq_puts(s, "\n"))
  822. goto partial;
  823. }
  824. return TRACE_TYPE_HANDLED;
  825. partial:
  826. return TRACE_TYPE_PARTIAL_LINE;
  827. }
  828. static struct trace_event trace_stack_event = {
  829. .type = TRACE_STACK,
  830. .trace = trace_stack_print,
  831. .raw = trace_special_print,
  832. .hex = trace_special_hex,
  833. .binary = trace_special_bin,
  834. };
  835. /* TRACE_USER_STACK */
  836. static enum print_line_t trace_user_stack_print(struct trace_iterator *iter,
  837. int flags)
  838. {
  839. struct userstack_entry *field;
  840. struct trace_seq *s = &iter->seq;
  841. trace_assign_type(field, iter->ent);
  842. if (!trace_seq_puts(s, "<user stack trace>\n"))
  843. goto partial;
  844. if (!seq_print_userip_objs(field, s, flags))
  845. goto partial;
  846. return TRACE_TYPE_HANDLED;
  847. partial:
  848. return TRACE_TYPE_PARTIAL_LINE;
  849. }
  850. static struct trace_event trace_user_stack_event = {
  851. .type = TRACE_USER_STACK,
  852. .trace = trace_user_stack_print,
  853. .raw = trace_special_print,
  854. .hex = trace_special_hex,
  855. .binary = trace_special_bin,
  856. };
  857. /* TRACE_BPRINT */
  858. static enum print_line_t
  859. trace_bprint_print(struct trace_iterator *iter, int flags)
  860. {
  861. struct trace_entry *entry = iter->ent;
  862. struct trace_seq *s = &iter->seq;
  863. struct bprint_entry *field;
  864. trace_assign_type(field, entry);
  865. if (!seq_print_ip_sym(s, field->ip, flags))
  866. goto partial;
  867. if (!trace_seq_puts(s, ": "))
  868. goto partial;
  869. if (!trace_seq_bprintf(s, field->fmt, field->buf))
  870. goto partial;
  871. return TRACE_TYPE_HANDLED;
  872. partial:
  873. return TRACE_TYPE_PARTIAL_LINE;
  874. }
  875. static enum print_line_t
  876. trace_bprint_raw(struct trace_iterator *iter, int flags)
  877. {
  878. struct bprint_entry *field;
  879. struct trace_seq *s = &iter->seq;
  880. trace_assign_type(field, iter->ent);
  881. if (!trace_seq_printf(s, ": %lx : ", field->ip))
  882. goto partial;
  883. if (!trace_seq_bprintf(s, field->fmt, field->buf))
  884. goto partial;
  885. return TRACE_TYPE_HANDLED;
  886. partial:
  887. return TRACE_TYPE_PARTIAL_LINE;
  888. }
  889. static struct trace_event trace_bprint_event = {
  890. .type = TRACE_BPRINT,
  891. .trace = trace_bprint_print,
  892. .raw = trace_bprint_raw,
  893. };
  894. /* TRACE_PRINT */
  895. static enum print_line_t trace_print_print(struct trace_iterator *iter,
  896. int flags)
  897. {
  898. struct print_entry *field;
  899. struct trace_seq *s = &iter->seq;
  900. trace_assign_type(field, iter->ent);
  901. if (!seq_print_ip_sym(s, field->ip, flags))
  902. goto partial;
  903. if (!trace_seq_printf(s, ": %s", field->buf))
  904. goto partial;
  905. return TRACE_TYPE_HANDLED;
  906. partial:
  907. return TRACE_TYPE_PARTIAL_LINE;
  908. }
  909. static enum print_line_t trace_print_raw(struct trace_iterator *iter, int flags)
  910. {
  911. struct print_entry *field;
  912. trace_assign_type(field, iter->ent);
  913. if (!trace_seq_printf(&iter->seq, "# %lx %s", field->ip, field->buf))
  914. goto partial;
  915. return TRACE_TYPE_HANDLED;
  916. partial:
  917. return TRACE_TYPE_PARTIAL_LINE;
  918. }
  919. static struct trace_event trace_print_event = {
  920. .type = TRACE_PRINT,
  921. .trace = trace_print_print,
  922. .raw = trace_print_raw,
  923. };
  924. static struct trace_event *events[] __initdata = {
  925. &trace_fn_event,
  926. &trace_ctx_event,
  927. &trace_wake_event,
  928. &trace_special_event,
  929. &trace_stack_event,
  930. &trace_user_stack_event,
  931. &trace_bprint_event,
  932. &trace_print_event,
  933. NULL
  934. };
  935. __init static int init_events(void)
  936. {
  937. struct trace_event *event;
  938. int i, ret;
  939. for (i = 0; events[i]; i++) {
  940. event = events[i];
  941. ret = register_ftrace_event(event);
  942. if (!ret) {
  943. printk(KERN_WARNING "event %d failed to register\n",
  944. event->type);
  945. WARN_ON_ONCE(1);
  946. }
  947. }
  948. return 0;
  949. }
  950. device_initcall(init_events);