trace_output.c 28 KB

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  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. static struct hlist_head event_hash[EVENT_HASHSIZE] __read_mostly;
  15. static int next_event_type = __TRACE_LAST_TYPE + 1;
  16. int trace_print_seq(struct seq_file *m, struct trace_seq *s)
  17. {
  18. int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len;
  19. int ret;
  20. ret = seq_write(m, s->buffer, len);
  21. /*
  22. * Only reset this buffer if we successfully wrote to the
  23. * seq_file buffer.
  24. */
  25. if (!ret)
  26. trace_seq_init(s);
  27. return ret;
  28. }
  29. enum print_line_t trace_print_bprintk_msg_only(struct trace_iterator *iter)
  30. {
  31. struct trace_seq *s = &iter->seq;
  32. struct trace_entry *entry = iter->ent;
  33. struct bprint_entry *field;
  34. int ret;
  35. trace_assign_type(field, entry);
  36. ret = trace_seq_bprintf(s, field->fmt, field->buf);
  37. if (!ret)
  38. return TRACE_TYPE_PARTIAL_LINE;
  39. return TRACE_TYPE_HANDLED;
  40. }
  41. enum print_line_t trace_print_printk_msg_only(struct trace_iterator *iter)
  42. {
  43. struct trace_seq *s = &iter->seq;
  44. struct trace_entry *entry = iter->ent;
  45. struct print_entry *field;
  46. int ret;
  47. trace_assign_type(field, entry);
  48. ret = trace_seq_printf(s, "%s", field->buf);
  49. if (!ret)
  50. return TRACE_TYPE_PARTIAL_LINE;
  51. return TRACE_TYPE_HANDLED;
  52. }
  53. /**
  54. * trace_seq_printf - sequence printing of trace information
  55. * @s: trace sequence descriptor
  56. * @fmt: printf format string
  57. *
  58. * It returns 0 if the trace oversizes the buffer's free
  59. * space, 1 otherwise.
  60. *
  61. * The tracer may use either sequence operations or its own
  62. * copy to user routines. To simplify formating of a trace
  63. * trace_seq_printf is used to store strings into a special
  64. * buffer (@s). Then the output may be either used by
  65. * the sequencer or pulled into another buffer.
  66. */
  67. int
  68. trace_seq_printf(struct trace_seq *s, const char *fmt, ...)
  69. {
  70. int len = (PAGE_SIZE - 1) - s->len;
  71. va_list ap;
  72. int ret;
  73. if (s->full || !len)
  74. return 0;
  75. va_start(ap, fmt);
  76. ret = vsnprintf(s->buffer + s->len, len, fmt, ap);
  77. va_end(ap);
  78. /* If we can't write it all, don't bother writing anything */
  79. if (ret >= len) {
  80. s->full = 1;
  81. return 0;
  82. }
  83. s->len += ret;
  84. return 1;
  85. }
  86. EXPORT_SYMBOL_GPL(trace_seq_printf);
  87. /**
  88. * trace_seq_vprintf - sequence printing of trace information
  89. * @s: trace sequence descriptor
  90. * @fmt: printf format string
  91. *
  92. * The tracer may use either sequence operations or its own
  93. * copy to user routines. To simplify formating of a trace
  94. * trace_seq_printf is used to store strings into a special
  95. * buffer (@s). Then the output may be either used by
  96. * the sequencer or pulled into another buffer.
  97. */
  98. int
  99. trace_seq_vprintf(struct trace_seq *s, const char *fmt, va_list args)
  100. {
  101. int len = (PAGE_SIZE - 1) - s->len;
  102. int ret;
  103. if (s->full || !len)
  104. return 0;
  105. ret = vsnprintf(s->buffer + s->len, len, fmt, args);
  106. /* If we can't write it all, don't bother writing anything */
  107. if (ret >= len) {
  108. s->full = 1;
  109. return 0;
  110. }
  111. s->len += ret;
  112. return len;
  113. }
  114. EXPORT_SYMBOL_GPL(trace_seq_vprintf);
  115. int trace_seq_bprintf(struct trace_seq *s, const char *fmt, const u32 *binary)
  116. {
  117. int len = (PAGE_SIZE - 1) - s->len;
  118. int ret;
  119. if (s->full || !len)
  120. return 0;
  121. ret = bstr_printf(s->buffer + s->len, len, fmt, binary);
  122. /* If we can't write it all, don't bother writing anything */
  123. if (ret >= len) {
  124. s->full = 1;
  125. return 0;
  126. }
  127. s->len += ret;
  128. return len;
  129. }
  130. /**
  131. * trace_seq_puts - trace sequence printing of simple string
  132. * @s: trace sequence descriptor
  133. * @str: simple string to record
  134. *
  135. * The tracer may use either the sequence operations or its own
  136. * copy to user routines. This function records a simple string
  137. * into a special buffer (@s) for later retrieval by a sequencer
  138. * or other mechanism.
  139. */
  140. int trace_seq_puts(struct trace_seq *s, const char *str)
  141. {
  142. int len = strlen(str);
  143. if (s->full)
  144. return 0;
  145. if (len > ((PAGE_SIZE - 1) - s->len)) {
  146. s->full = 1;
  147. return 0;
  148. }
  149. memcpy(s->buffer + s->len, str, len);
  150. s->len += len;
  151. return len;
  152. }
  153. int trace_seq_putc(struct trace_seq *s, unsigned char c)
  154. {
  155. if (s->full)
  156. return 0;
  157. if (s->len >= (PAGE_SIZE - 1)) {
  158. s->full = 1;
  159. return 0;
  160. }
  161. s->buffer[s->len++] = c;
  162. return 1;
  163. }
  164. EXPORT_SYMBOL(trace_seq_putc);
  165. int trace_seq_putmem(struct trace_seq *s, const void *mem, size_t len)
  166. {
  167. if (s->full)
  168. return 0;
  169. if (len > ((PAGE_SIZE - 1) - s->len)) {
  170. s->full = 1;
  171. return 0;
  172. }
  173. memcpy(s->buffer + s->len, mem, len);
  174. s->len += len;
  175. return len;
  176. }
  177. int trace_seq_putmem_hex(struct trace_seq *s, const void *mem, size_t len)
  178. {
  179. unsigned char hex[HEX_CHARS];
  180. const unsigned char *data = mem;
  181. int i, j;
  182. if (s->full)
  183. return 0;
  184. #ifdef __BIG_ENDIAN
  185. for (i = 0, j = 0; i < len; i++) {
  186. #else
  187. for (i = len-1, j = 0; i >= 0; i--) {
  188. #endif
  189. hex[j++] = hex_asc_hi(data[i]);
  190. hex[j++] = hex_asc_lo(data[i]);
  191. }
  192. hex[j++] = ' ';
  193. return trace_seq_putmem(s, hex, j);
  194. }
  195. void *trace_seq_reserve(struct trace_seq *s, size_t len)
  196. {
  197. void *ret;
  198. if (s->full)
  199. return NULL;
  200. if (len > ((PAGE_SIZE - 1) - s->len)) {
  201. s->full = 1;
  202. return NULL;
  203. }
  204. ret = s->buffer + s->len;
  205. s->len += len;
  206. return ret;
  207. }
  208. int trace_seq_path(struct trace_seq *s, const struct path *path)
  209. {
  210. unsigned char *p;
  211. if (s->full)
  212. return 0;
  213. if (s->len >= (PAGE_SIZE - 1)) {
  214. s->full = 1;
  215. return 0;
  216. }
  217. p = d_path(path, s->buffer + s->len, PAGE_SIZE - s->len);
  218. if (!IS_ERR(p)) {
  219. p = mangle_path(s->buffer + s->len, p, "\n");
  220. if (p) {
  221. s->len = p - s->buffer;
  222. return 1;
  223. }
  224. } else {
  225. s->buffer[s->len++] = '?';
  226. return 1;
  227. }
  228. s->full = 1;
  229. return 0;
  230. }
  231. const char *
  232. ftrace_print_flags_seq(struct trace_seq *p, const char *delim,
  233. unsigned long flags,
  234. const struct trace_print_flags *flag_array)
  235. {
  236. unsigned long mask;
  237. const char *str;
  238. const char *ret = p->buffer + p->len;
  239. int i, first = 1;
  240. for (i = 0; flag_array[i].name && flags; i++) {
  241. mask = flag_array[i].mask;
  242. if ((flags & mask) != mask)
  243. continue;
  244. str = flag_array[i].name;
  245. flags &= ~mask;
  246. if (!first && delim)
  247. trace_seq_puts(p, delim);
  248. else
  249. first = 0;
  250. trace_seq_puts(p, str);
  251. }
  252. /* check for left over flags */
  253. if (flags) {
  254. if (!first && delim)
  255. trace_seq_puts(p, delim);
  256. trace_seq_printf(p, "0x%lx", flags);
  257. }
  258. trace_seq_putc(p, 0);
  259. return ret;
  260. }
  261. EXPORT_SYMBOL(ftrace_print_flags_seq);
  262. const char *
  263. ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val,
  264. const struct trace_print_flags *symbol_array)
  265. {
  266. int i;
  267. const char *ret = p->buffer + p->len;
  268. for (i = 0; symbol_array[i].name; i++) {
  269. if (val != symbol_array[i].mask)
  270. continue;
  271. trace_seq_puts(p, symbol_array[i].name);
  272. break;
  273. }
  274. if (ret == (const char *)(p->buffer + p->len))
  275. trace_seq_printf(p, "0x%lx", val);
  276. trace_seq_putc(p, 0);
  277. return ret;
  278. }
  279. EXPORT_SYMBOL(ftrace_print_symbols_seq);
  280. #if BITS_PER_LONG == 32
  281. const char *
  282. ftrace_print_symbols_seq_u64(struct trace_seq *p, unsigned long long val,
  283. const struct trace_print_flags_u64 *symbol_array)
  284. {
  285. int i;
  286. const char *ret = p->buffer + p->len;
  287. for (i = 0; symbol_array[i].name; i++) {
  288. if (val != symbol_array[i].mask)
  289. continue;
  290. trace_seq_puts(p, symbol_array[i].name);
  291. break;
  292. }
  293. if (ret == (const char *)(p->buffer + p->len))
  294. trace_seq_printf(p, "0x%llx", val);
  295. trace_seq_putc(p, 0);
  296. return ret;
  297. }
  298. EXPORT_SYMBOL(ftrace_print_symbols_seq_u64);
  299. #endif
  300. const char *
  301. ftrace_print_hex_seq(struct trace_seq *p, const unsigned char *buf, int buf_len)
  302. {
  303. int i;
  304. const char *ret = p->buffer + p->len;
  305. for (i = 0; i < buf_len; i++)
  306. trace_seq_printf(p, "%s%2.2x", i == 0 ? "" : " ", buf[i]);
  307. trace_seq_putc(p, 0);
  308. return ret;
  309. }
  310. EXPORT_SYMBOL(ftrace_print_hex_seq);
  311. #ifdef CONFIG_KRETPROBES
  312. static inline const char *kretprobed(const char *name)
  313. {
  314. static const char tramp_name[] = "kretprobe_trampoline";
  315. int size = sizeof(tramp_name);
  316. if (strncmp(tramp_name, name, size) == 0)
  317. return "[unknown/kretprobe'd]";
  318. return name;
  319. }
  320. #else
  321. static inline const char *kretprobed(const char *name)
  322. {
  323. return name;
  324. }
  325. #endif /* CONFIG_KRETPROBES */
  326. static int
  327. seq_print_sym_short(struct trace_seq *s, const char *fmt, unsigned long address)
  328. {
  329. #ifdef CONFIG_KALLSYMS
  330. char str[KSYM_SYMBOL_LEN];
  331. const char *name;
  332. kallsyms_lookup(address, NULL, NULL, NULL, str);
  333. name = kretprobed(str);
  334. return trace_seq_printf(s, fmt, name);
  335. #endif
  336. return 1;
  337. }
  338. static int
  339. seq_print_sym_offset(struct trace_seq *s, const char *fmt,
  340. unsigned long address)
  341. {
  342. #ifdef CONFIG_KALLSYMS
  343. char str[KSYM_SYMBOL_LEN];
  344. const char *name;
  345. sprint_symbol(str, address);
  346. name = kretprobed(str);
  347. return trace_seq_printf(s, fmt, name);
  348. #endif
  349. return 1;
  350. }
  351. #ifndef CONFIG_64BIT
  352. # define IP_FMT "%08lx"
  353. #else
  354. # define IP_FMT "%016lx"
  355. #endif
  356. int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm,
  357. unsigned long ip, unsigned long sym_flags)
  358. {
  359. struct file *file = NULL;
  360. unsigned long vmstart = 0;
  361. int ret = 1;
  362. if (s->full)
  363. return 0;
  364. if (mm) {
  365. const struct vm_area_struct *vma;
  366. down_read(&mm->mmap_sem);
  367. vma = find_vma(mm, ip);
  368. if (vma) {
  369. file = vma->vm_file;
  370. vmstart = vma->vm_start;
  371. }
  372. if (file) {
  373. ret = trace_seq_path(s, &file->f_path);
  374. if (ret)
  375. ret = trace_seq_printf(s, "[+0x%lx]",
  376. ip - vmstart);
  377. }
  378. up_read(&mm->mmap_sem);
  379. }
  380. if (ret && ((sym_flags & TRACE_ITER_SYM_ADDR) || !file))
  381. ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
  382. return ret;
  383. }
  384. int
  385. seq_print_userip_objs(const struct userstack_entry *entry, struct trace_seq *s,
  386. unsigned long sym_flags)
  387. {
  388. struct mm_struct *mm = NULL;
  389. int ret = 1;
  390. unsigned int i;
  391. if (trace_flags & TRACE_ITER_SYM_USEROBJ) {
  392. struct task_struct *task;
  393. /*
  394. * we do the lookup on the thread group leader,
  395. * since individual threads might have already quit!
  396. */
  397. rcu_read_lock();
  398. task = find_task_by_vpid(entry->tgid);
  399. if (task)
  400. mm = get_task_mm(task);
  401. rcu_read_unlock();
  402. }
  403. for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
  404. unsigned long ip = entry->caller[i];
  405. if (ip == ULONG_MAX || !ret)
  406. break;
  407. if (ret)
  408. ret = trace_seq_puts(s, " => ");
  409. if (!ip) {
  410. if (ret)
  411. ret = trace_seq_puts(s, "??");
  412. if (ret)
  413. ret = trace_seq_puts(s, "\n");
  414. continue;
  415. }
  416. if (!ret)
  417. break;
  418. if (ret)
  419. ret = seq_print_user_ip(s, mm, ip, sym_flags);
  420. ret = trace_seq_puts(s, "\n");
  421. }
  422. if (mm)
  423. mmput(mm);
  424. return ret;
  425. }
  426. int
  427. seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
  428. {
  429. int ret;
  430. if (!ip)
  431. return trace_seq_printf(s, "0");
  432. if (sym_flags & TRACE_ITER_SYM_OFFSET)
  433. ret = seq_print_sym_offset(s, "%s", ip);
  434. else
  435. ret = seq_print_sym_short(s, "%s", ip);
  436. if (!ret)
  437. return 0;
  438. if (sym_flags & TRACE_ITER_SYM_ADDR)
  439. ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
  440. return ret;
  441. }
  442. /**
  443. * trace_print_lat_fmt - print the irq, preempt and lockdep fields
  444. * @s: trace seq struct to write to
  445. * @entry: The trace entry field from the ring buffer
  446. *
  447. * Prints the generic fields of irqs off, in hard or softirq, preempt
  448. * count.
  449. */
  450. int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
  451. {
  452. char hardsoft_irq;
  453. char need_resched;
  454. char irqs_off;
  455. int hardirq;
  456. int softirq;
  457. int ret;
  458. hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
  459. softirq = entry->flags & TRACE_FLAG_SOFTIRQ;
  460. irqs_off =
  461. (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' :
  462. (entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ? 'X' :
  463. '.';
  464. need_resched =
  465. (entry->flags & TRACE_FLAG_NEED_RESCHED) ? 'N' : '.';
  466. hardsoft_irq =
  467. (hardirq && softirq) ? 'H' :
  468. hardirq ? 'h' :
  469. softirq ? 's' :
  470. '.';
  471. if (!trace_seq_printf(s, "%c%c%c",
  472. irqs_off, need_resched, hardsoft_irq))
  473. return 0;
  474. if (entry->preempt_count)
  475. ret = trace_seq_printf(s, "%x", entry->preempt_count);
  476. else
  477. ret = trace_seq_putc(s, '.');
  478. return ret;
  479. }
  480. static int
  481. lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
  482. {
  483. char comm[TASK_COMM_LEN];
  484. trace_find_cmdline(entry->pid, comm);
  485. if (!trace_seq_printf(s, "%8.8s-%-5d %3d",
  486. comm, entry->pid, cpu))
  487. return 0;
  488. return trace_print_lat_fmt(s, entry);
  489. }
  490. static unsigned long preempt_mark_thresh = 100;
  491. static int
  492. lat_print_timestamp(struct trace_seq *s, u64 abs_usecs,
  493. unsigned long rel_usecs)
  494. {
  495. return trace_seq_printf(s, " %4lldus%c: ", abs_usecs,
  496. rel_usecs > preempt_mark_thresh ? '!' :
  497. rel_usecs > 1 ? '+' : ' ');
  498. }
  499. int trace_print_context(struct trace_iterator *iter)
  500. {
  501. struct trace_seq *s = &iter->seq;
  502. struct trace_entry *entry = iter->ent;
  503. unsigned long long t = ns2usecs(iter->ts);
  504. unsigned long usec_rem = do_div(t, USEC_PER_SEC);
  505. unsigned long secs = (unsigned long)t;
  506. char comm[TASK_COMM_LEN];
  507. int ret;
  508. trace_find_cmdline(entry->pid, comm);
  509. ret = trace_seq_printf(s, "%16s-%-5d [%03d] ",
  510. comm, entry->pid, iter->cpu);
  511. if (!ret)
  512. return 0;
  513. if (trace_flags & TRACE_ITER_IRQ_INFO) {
  514. ret = trace_print_lat_fmt(s, entry);
  515. if (!ret)
  516. return 0;
  517. }
  518. return trace_seq_printf(s, " %5lu.%06lu: ",
  519. secs, usec_rem);
  520. }
  521. int trace_print_lat_context(struct trace_iterator *iter)
  522. {
  523. u64 next_ts;
  524. int ret;
  525. /* trace_find_next_entry will reset ent_size */
  526. int ent_size = iter->ent_size;
  527. struct trace_seq *s = &iter->seq;
  528. struct trace_entry *entry = iter->ent,
  529. *next_entry = trace_find_next_entry(iter, NULL,
  530. &next_ts);
  531. unsigned long verbose = (trace_flags & TRACE_ITER_VERBOSE);
  532. unsigned long abs_usecs = ns2usecs(iter->ts - iter->tr->time_start);
  533. unsigned long rel_usecs;
  534. /* Restore the original ent_size */
  535. iter->ent_size = ent_size;
  536. if (!next_entry)
  537. next_ts = iter->ts;
  538. rel_usecs = ns2usecs(next_ts - iter->ts);
  539. if (verbose) {
  540. char comm[TASK_COMM_LEN];
  541. trace_find_cmdline(entry->pid, comm);
  542. ret = trace_seq_printf(s, "%16s %5d %3d %d %08x %08lx [%08llx]"
  543. " %ld.%03ldms (+%ld.%03ldms): ", comm,
  544. entry->pid, iter->cpu, entry->flags,
  545. entry->preempt_count, iter->idx,
  546. ns2usecs(iter->ts),
  547. abs_usecs / USEC_PER_MSEC,
  548. abs_usecs % USEC_PER_MSEC,
  549. rel_usecs / USEC_PER_MSEC,
  550. rel_usecs % USEC_PER_MSEC);
  551. } else {
  552. ret = lat_print_generic(s, entry, iter->cpu);
  553. if (ret)
  554. ret = lat_print_timestamp(s, abs_usecs, rel_usecs);
  555. }
  556. return ret;
  557. }
  558. static const char state_to_char[] = TASK_STATE_TO_CHAR_STR;
  559. static int task_state_char(unsigned long state)
  560. {
  561. int bit = state ? __ffs(state) + 1 : 0;
  562. return bit < sizeof(state_to_char) - 1 ? state_to_char[bit] : '?';
  563. }
  564. /**
  565. * ftrace_find_event - find a registered event
  566. * @type: the type of event to look for
  567. *
  568. * Returns an event of type @type otherwise NULL
  569. * Called with trace_event_read_lock() held.
  570. */
  571. struct trace_event *ftrace_find_event(int type)
  572. {
  573. struct trace_event *event;
  574. struct hlist_node *n;
  575. unsigned key;
  576. key = type & (EVENT_HASHSIZE - 1);
  577. hlist_for_each_entry(event, n, &event_hash[key], node) {
  578. if (event->type == type)
  579. return event;
  580. }
  581. return NULL;
  582. }
  583. static LIST_HEAD(ftrace_event_list);
  584. static int trace_search_list(struct list_head **list)
  585. {
  586. struct trace_event *e;
  587. int last = __TRACE_LAST_TYPE;
  588. if (list_empty(&ftrace_event_list)) {
  589. *list = &ftrace_event_list;
  590. return last + 1;
  591. }
  592. /*
  593. * We used up all possible max events,
  594. * lets see if somebody freed one.
  595. */
  596. list_for_each_entry(e, &ftrace_event_list, list) {
  597. if (e->type != last + 1)
  598. break;
  599. last++;
  600. }
  601. /* Did we used up all 65 thousand events??? */
  602. if ((last + 1) > FTRACE_MAX_EVENT)
  603. return 0;
  604. *list = &e->list;
  605. return last + 1;
  606. }
  607. void trace_event_read_lock(void)
  608. {
  609. down_read(&trace_event_mutex);
  610. }
  611. void trace_event_read_unlock(void)
  612. {
  613. up_read(&trace_event_mutex);
  614. }
  615. /**
  616. * register_ftrace_event - register output for an event type
  617. * @event: the event type to register
  618. *
  619. * Event types are stored in a hash and this hash is used to
  620. * find a way to print an event. If the @event->type is set
  621. * then it will use that type, otherwise it will assign a
  622. * type to use.
  623. *
  624. * If you assign your own type, please make sure it is added
  625. * to the trace_type enum in trace.h, to avoid collisions
  626. * with the dynamic types.
  627. *
  628. * Returns the event type number or zero on error.
  629. */
  630. int register_ftrace_event(struct trace_event *event)
  631. {
  632. unsigned key;
  633. int ret = 0;
  634. down_write(&trace_event_mutex);
  635. if (WARN_ON(!event))
  636. goto out;
  637. if (WARN_ON(!event->funcs))
  638. goto out;
  639. INIT_LIST_HEAD(&event->list);
  640. if (!event->type) {
  641. struct list_head *list = NULL;
  642. if (next_event_type > FTRACE_MAX_EVENT) {
  643. event->type = trace_search_list(&list);
  644. if (!event->type)
  645. goto out;
  646. } else {
  647. event->type = next_event_type++;
  648. list = &ftrace_event_list;
  649. }
  650. if (WARN_ON(ftrace_find_event(event->type)))
  651. goto out;
  652. list_add_tail(&event->list, list);
  653. } else if (event->type > __TRACE_LAST_TYPE) {
  654. printk(KERN_WARNING "Need to add type to trace.h\n");
  655. WARN_ON(1);
  656. goto out;
  657. } else {
  658. /* Is this event already used */
  659. if (ftrace_find_event(event->type))
  660. goto out;
  661. }
  662. if (event->funcs->trace == NULL)
  663. event->funcs->trace = trace_nop_print;
  664. if (event->funcs->raw == NULL)
  665. event->funcs->raw = trace_nop_print;
  666. if (event->funcs->hex == NULL)
  667. event->funcs->hex = trace_nop_print;
  668. if (event->funcs->binary == NULL)
  669. event->funcs->binary = trace_nop_print;
  670. key = event->type & (EVENT_HASHSIZE - 1);
  671. hlist_add_head(&event->node, &event_hash[key]);
  672. ret = event->type;
  673. out:
  674. up_write(&trace_event_mutex);
  675. return ret;
  676. }
  677. EXPORT_SYMBOL_GPL(register_ftrace_event);
  678. /*
  679. * Used by module code with the trace_event_mutex held for write.
  680. */
  681. int __unregister_ftrace_event(struct trace_event *event)
  682. {
  683. hlist_del(&event->node);
  684. list_del(&event->list);
  685. return 0;
  686. }
  687. /**
  688. * unregister_ftrace_event - remove a no longer used event
  689. * @event: the event to remove
  690. */
  691. int unregister_ftrace_event(struct trace_event *event)
  692. {
  693. down_write(&trace_event_mutex);
  694. __unregister_ftrace_event(event);
  695. up_write(&trace_event_mutex);
  696. return 0;
  697. }
  698. EXPORT_SYMBOL_GPL(unregister_ftrace_event);
  699. /*
  700. * Standard events
  701. */
  702. enum print_line_t trace_nop_print(struct trace_iterator *iter, int flags,
  703. struct trace_event *event)
  704. {
  705. if (!trace_seq_printf(&iter->seq, "type: %d\n", iter->ent->type))
  706. return TRACE_TYPE_PARTIAL_LINE;
  707. return TRACE_TYPE_HANDLED;
  708. }
  709. /* TRACE_FN */
  710. static enum print_line_t trace_fn_trace(struct trace_iterator *iter, int flags,
  711. struct trace_event *event)
  712. {
  713. struct ftrace_entry *field;
  714. struct trace_seq *s = &iter->seq;
  715. trace_assign_type(field, iter->ent);
  716. if (!seq_print_ip_sym(s, field->ip, flags))
  717. goto partial;
  718. if ((flags & TRACE_ITER_PRINT_PARENT) && field->parent_ip) {
  719. if (!trace_seq_printf(s, " <-"))
  720. goto partial;
  721. if (!seq_print_ip_sym(s,
  722. field->parent_ip,
  723. flags))
  724. goto partial;
  725. }
  726. if (!trace_seq_printf(s, "\n"))
  727. goto partial;
  728. return TRACE_TYPE_HANDLED;
  729. partial:
  730. return TRACE_TYPE_PARTIAL_LINE;
  731. }
  732. static enum print_line_t trace_fn_raw(struct trace_iterator *iter, int flags,
  733. struct trace_event *event)
  734. {
  735. struct ftrace_entry *field;
  736. trace_assign_type(field, iter->ent);
  737. if (!trace_seq_printf(&iter->seq, "%lx %lx\n",
  738. field->ip,
  739. field->parent_ip))
  740. return TRACE_TYPE_PARTIAL_LINE;
  741. return TRACE_TYPE_HANDLED;
  742. }
  743. static enum print_line_t trace_fn_hex(struct trace_iterator *iter, int flags,
  744. struct trace_event *event)
  745. {
  746. struct ftrace_entry *field;
  747. struct trace_seq *s = &iter->seq;
  748. trace_assign_type(field, iter->ent);
  749. SEQ_PUT_HEX_FIELD_RET(s, field->ip);
  750. SEQ_PUT_HEX_FIELD_RET(s, field->parent_ip);
  751. return TRACE_TYPE_HANDLED;
  752. }
  753. static enum print_line_t trace_fn_bin(struct trace_iterator *iter, int flags,
  754. struct trace_event *event)
  755. {
  756. struct ftrace_entry *field;
  757. struct trace_seq *s = &iter->seq;
  758. trace_assign_type(field, iter->ent);
  759. SEQ_PUT_FIELD_RET(s, field->ip);
  760. SEQ_PUT_FIELD_RET(s, field->parent_ip);
  761. return TRACE_TYPE_HANDLED;
  762. }
  763. static struct trace_event_functions trace_fn_funcs = {
  764. .trace = trace_fn_trace,
  765. .raw = trace_fn_raw,
  766. .hex = trace_fn_hex,
  767. .binary = trace_fn_bin,
  768. };
  769. static struct trace_event trace_fn_event = {
  770. .type = TRACE_FN,
  771. .funcs = &trace_fn_funcs,
  772. };
  773. /* TRACE_CTX an TRACE_WAKE */
  774. static enum print_line_t trace_ctxwake_print(struct trace_iterator *iter,
  775. char *delim)
  776. {
  777. struct ctx_switch_entry *field;
  778. char comm[TASK_COMM_LEN];
  779. int S, T;
  780. trace_assign_type(field, iter->ent);
  781. T = task_state_char(field->next_state);
  782. S = task_state_char(field->prev_state);
  783. trace_find_cmdline(field->next_pid, comm);
  784. if (!trace_seq_printf(&iter->seq,
  785. " %5d:%3d:%c %s [%03d] %5d:%3d:%c %s\n",
  786. field->prev_pid,
  787. field->prev_prio,
  788. S, delim,
  789. field->next_cpu,
  790. field->next_pid,
  791. field->next_prio,
  792. T, comm))
  793. return TRACE_TYPE_PARTIAL_LINE;
  794. return TRACE_TYPE_HANDLED;
  795. }
  796. static enum print_line_t trace_ctx_print(struct trace_iterator *iter, int flags,
  797. struct trace_event *event)
  798. {
  799. return trace_ctxwake_print(iter, "==>");
  800. }
  801. static enum print_line_t trace_wake_print(struct trace_iterator *iter,
  802. int flags, struct trace_event *event)
  803. {
  804. return trace_ctxwake_print(iter, " +");
  805. }
  806. static int trace_ctxwake_raw(struct trace_iterator *iter, char S)
  807. {
  808. struct ctx_switch_entry *field;
  809. int T;
  810. trace_assign_type(field, iter->ent);
  811. if (!S)
  812. S = task_state_char(field->prev_state);
  813. T = task_state_char(field->next_state);
  814. if (!trace_seq_printf(&iter->seq, "%d %d %c %d %d %d %c\n",
  815. field->prev_pid,
  816. field->prev_prio,
  817. S,
  818. field->next_cpu,
  819. field->next_pid,
  820. field->next_prio,
  821. T))
  822. return TRACE_TYPE_PARTIAL_LINE;
  823. return TRACE_TYPE_HANDLED;
  824. }
  825. static enum print_line_t trace_ctx_raw(struct trace_iterator *iter, int flags,
  826. struct trace_event *event)
  827. {
  828. return trace_ctxwake_raw(iter, 0);
  829. }
  830. static enum print_line_t trace_wake_raw(struct trace_iterator *iter, int flags,
  831. struct trace_event *event)
  832. {
  833. return trace_ctxwake_raw(iter, '+');
  834. }
  835. static int trace_ctxwake_hex(struct trace_iterator *iter, char S)
  836. {
  837. struct ctx_switch_entry *field;
  838. struct trace_seq *s = &iter->seq;
  839. int T;
  840. trace_assign_type(field, iter->ent);
  841. if (!S)
  842. S = task_state_char(field->prev_state);
  843. T = task_state_char(field->next_state);
  844. SEQ_PUT_HEX_FIELD_RET(s, field->prev_pid);
  845. SEQ_PUT_HEX_FIELD_RET(s, field->prev_prio);
  846. SEQ_PUT_HEX_FIELD_RET(s, S);
  847. SEQ_PUT_HEX_FIELD_RET(s, field->next_cpu);
  848. SEQ_PUT_HEX_FIELD_RET(s, field->next_pid);
  849. SEQ_PUT_HEX_FIELD_RET(s, field->next_prio);
  850. SEQ_PUT_HEX_FIELD_RET(s, T);
  851. return TRACE_TYPE_HANDLED;
  852. }
  853. static enum print_line_t trace_ctx_hex(struct trace_iterator *iter, int flags,
  854. struct trace_event *event)
  855. {
  856. return trace_ctxwake_hex(iter, 0);
  857. }
  858. static enum print_line_t trace_wake_hex(struct trace_iterator *iter, int flags,
  859. struct trace_event *event)
  860. {
  861. return trace_ctxwake_hex(iter, '+');
  862. }
  863. static enum print_line_t trace_ctxwake_bin(struct trace_iterator *iter,
  864. int flags, struct trace_event *event)
  865. {
  866. struct ctx_switch_entry *field;
  867. struct trace_seq *s = &iter->seq;
  868. trace_assign_type(field, iter->ent);
  869. SEQ_PUT_FIELD_RET(s, field->prev_pid);
  870. SEQ_PUT_FIELD_RET(s, field->prev_prio);
  871. SEQ_PUT_FIELD_RET(s, field->prev_state);
  872. SEQ_PUT_FIELD_RET(s, field->next_pid);
  873. SEQ_PUT_FIELD_RET(s, field->next_prio);
  874. SEQ_PUT_FIELD_RET(s, field->next_state);
  875. return TRACE_TYPE_HANDLED;
  876. }
  877. static struct trace_event_functions trace_ctx_funcs = {
  878. .trace = trace_ctx_print,
  879. .raw = trace_ctx_raw,
  880. .hex = trace_ctx_hex,
  881. .binary = trace_ctxwake_bin,
  882. };
  883. static struct trace_event trace_ctx_event = {
  884. .type = TRACE_CTX,
  885. .funcs = &trace_ctx_funcs,
  886. };
  887. static struct trace_event_functions trace_wake_funcs = {
  888. .trace = trace_wake_print,
  889. .raw = trace_wake_raw,
  890. .hex = trace_wake_hex,
  891. .binary = trace_ctxwake_bin,
  892. };
  893. static struct trace_event trace_wake_event = {
  894. .type = TRACE_WAKE,
  895. .funcs = &trace_wake_funcs,
  896. };
  897. /* TRACE_STACK */
  898. static enum print_line_t trace_stack_print(struct trace_iterator *iter,
  899. int flags, struct trace_event *event)
  900. {
  901. struct stack_entry *field;
  902. struct trace_seq *s = &iter->seq;
  903. unsigned long *p;
  904. unsigned long *end;
  905. trace_assign_type(field, iter->ent);
  906. end = (unsigned long *)((long)iter->ent + iter->ent_size);
  907. if (!trace_seq_puts(s, "<stack trace>\n"))
  908. goto partial;
  909. for (p = field->caller; p && *p != ULONG_MAX && p < end; p++) {
  910. if (!trace_seq_puts(s, " => "))
  911. goto partial;
  912. if (!seq_print_ip_sym(s, *p, flags))
  913. goto partial;
  914. if (!trace_seq_puts(s, "\n"))
  915. goto partial;
  916. }
  917. return TRACE_TYPE_HANDLED;
  918. partial:
  919. return TRACE_TYPE_PARTIAL_LINE;
  920. }
  921. static struct trace_event_functions trace_stack_funcs = {
  922. .trace = trace_stack_print,
  923. };
  924. static struct trace_event trace_stack_event = {
  925. .type = TRACE_STACK,
  926. .funcs = &trace_stack_funcs,
  927. };
  928. /* TRACE_USER_STACK */
  929. static enum print_line_t trace_user_stack_print(struct trace_iterator *iter,
  930. int flags, struct trace_event *event)
  931. {
  932. struct userstack_entry *field;
  933. struct trace_seq *s = &iter->seq;
  934. trace_assign_type(field, iter->ent);
  935. if (!trace_seq_puts(s, "<user stack trace>\n"))
  936. goto partial;
  937. if (!seq_print_userip_objs(field, s, flags))
  938. goto partial;
  939. return TRACE_TYPE_HANDLED;
  940. partial:
  941. return TRACE_TYPE_PARTIAL_LINE;
  942. }
  943. static struct trace_event_functions trace_user_stack_funcs = {
  944. .trace = trace_user_stack_print,
  945. };
  946. static struct trace_event trace_user_stack_event = {
  947. .type = TRACE_USER_STACK,
  948. .funcs = &trace_user_stack_funcs,
  949. };
  950. /* TRACE_BPRINT */
  951. static enum print_line_t
  952. trace_bprint_print(struct trace_iterator *iter, int flags,
  953. struct trace_event *event)
  954. {
  955. struct trace_entry *entry = iter->ent;
  956. struct trace_seq *s = &iter->seq;
  957. struct bprint_entry *field;
  958. trace_assign_type(field, entry);
  959. if (!seq_print_ip_sym(s, field->ip, flags))
  960. goto partial;
  961. if (!trace_seq_puts(s, ": "))
  962. goto partial;
  963. if (!trace_seq_bprintf(s, field->fmt, field->buf))
  964. goto partial;
  965. return TRACE_TYPE_HANDLED;
  966. partial:
  967. return TRACE_TYPE_PARTIAL_LINE;
  968. }
  969. static enum print_line_t
  970. trace_bprint_raw(struct trace_iterator *iter, int flags,
  971. struct trace_event *event)
  972. {
  973. struct bprint_entry *field;
  974. struct trace_seq *s = &iter->seq;
  975. trace_assign_type(field, iter->ent);
  976. if (!trace_seq_printf(s, ": %lx : ", field->ip))
  977. goto partial;
  978. if (!trace_seq_bprintf(s, field->fmt, field->buf))
  979. goto partial;
  980. return TRACE_TYPE_HANDLED;
  981. partial:
  982. return TRACE_TYPE_PARTIAL_LINE;
  983. }
  984. static struct trace_event_functions trace_bprint_funcs = {
  985. .trace = trace_bprint_print,
  986. .raw = trace_bprint_raw,
  987. };
  988. static struct trace_event trace_bprint_event = {
  989. .type = TRACE_BPRINT,
  990. .funcs = &trace_bprint_funcs,
  991. };
  992. /* TRACE_PRINT */
  993. static enum print_line_t trace_print_print(struct trace_iterator *iter,
  994. int flags, struct trace_event *event)
  995. {
  996. struct print_entry *field;
  997. struct trace_seq *s = &iter->seq;
  998. trace_assign_type(field, iter->ent);
  999. if (!seq_print_ip_sym(s, field->ip, flags))
  1000. goto partial;
  1001. if (!trace_seq_printf(s, ": %s", field->buf))
  1002. goto partial;
  1003. return TRACE_TYPE_HANDLED;
  1004. partial:
  1005. return TRACE_TYPE_PARTIAL_LINE;
  1006. }
  1007. static enum print_line_t trace_print_raw(struct trace_iterator *iter, int flags,
  1008. struct trace_event *event)
  1009. {
  1010. struct print_entry *field;
  1011. trace_assign_type(field, iter->ent);
  1012. if (!trace_seq_printf(&iter->seq, "# %lx %s", field->ip, field->buf))
  1013. goto partial;
  1014. return TRACE_TYPE_HANDLED;
  1015. partial:
  1016. return TRACE_TYPE_PARTIAL_LINE;
  1017. }
  1018. static struct trace_event_functions trace_print_funcs = {
  1019. .trace = trace_print_print,
  1020. .raw = trace_print_raw,
  1021. };
  1022. static struct trace_event trace_print_event = {
  1023. .type = TRACE_PRINT,
  1024. .funcs = &trace_print_funcs,
  1025. };
  1026. static struct trace_event *events[] __initdata = {
  1027. &trace_fn_event,
  1028. &trace_ctx_event,
  1029. &trace_wake_event,
  1030. &trace_stack_event,
  1031. &trace_user_stack_event,
  1032. &trace_bprint_event,
  1033. &trace_print_event,
  1034. NULL
  1035. };
  1036. __init static int init_events(void)
  1037. {
  1038. struct trace_event *event;
  1039. int i, ret;
  1040. for (i = 0; events[i]; i++) {
  1041. event = events[i];
  1042. ret = register_ftrace_event(event);
  1043. if (!ret) {
  1044. printk(KERN_WARNING "event %d failed to register\n",
  1045. event->type);
  1046. WARN_ON_ONCE(1);
  1047. }
  1048. }
  1049. return 0;
  1050. }
  1051. early_initcall(init_events);