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. struct trace_seq *s = &iter->seq;
  526. struct trace_entry *entry = iter->ent,
  527. *next_entry = trace_find_next_entry(iter, NULL,
  528. &next_ts);
  529. unsigned long verbose = (trace_flags & TRACE_ITER_VERBOSE);
  530. unsigned long abs_usecs = ns2usecs(iter->ts - iter->tr->time_start);
  531. unsigned long rel_usecs;
  532. if (!next_entry)
  533. next_ts = iter->ts;
  534. rel_usecs = ns2usecs(next_ts - iter->ts);
  535. if (verbose) {
  536. char comm[TASK_COMM_LEN];
  537. trace_find_cmdline(entry->pid, comm);
  538. ret = trace_seq_printf(s, "%16s %5d %3d %d %08x %08lx [%08llx]"
  539. " %ld.%03ldms (+%ld.%03ldms): ", comm,
  540. entry->pid, iter->cpu, entry->flags,
  541. entry->preempt_count, iter->idx,
  542. ns2usecs(iter->ts),
  543. abs_usecs / USEC_PER_MSEC,
  544. abs_usecs % USEC_PER_MSEC,
  545. rel_usecs / USEC_PER_MSEC,
  546. rel_usecs % USEC_PER_MSEC);
  547. } else {
  548. ret = lat_print_generic(s, entry, iter->cpu);
  549. if (ret)
  550. ret = lat_print_timestamp(s, abs_usecs, rel_usecs);
  551. }
  552. return ret;
  553. }
  554. static const char state_to_char[] = TASK_STATE_TO_CHAR_STR;
  555. static int task_state_char(unsigned long state)
  556. {
  557. int bit = state ? __ffs(state) + 1 : 0;
  558. return bit < sizeof(state_to_char) - 1 ? state_to_char[bit] : '?';
  559. }
  560. /**
  561. * ftrace_find_event - find a registered event
  562. * @type: the type of event to look for
  563. *
  564. * Returns an event of type @type otherwise NULL
  565. * Called with trace_event_read_lock() held.
  566. */
  567. struct trace_event *ftrace_find_event(int type)
  568. {
  569. struct trace_event *event;
  570. struct hlist_node *n;
  571. unsigned key;
  572. key = type & (EVENT_HASHSIZE - 1);
  573. hlist_for_each_entry(event, n, &event_hash[key], node) {
  574. if (event->type == type)
  575. return event;
  576. }
  577. return NULL;
  578. }
  579. static LIST_HEAD(ftrace_event_list);
  580. static int trace_search_list(struct list_head **list)
  581. {
  582. struct trace_event *e;
  583. int last = __TRACE_LAST_TYPE;
  584. if (list_empty(&ftrace_event_list)) {
  585. *list = &ftrace_event_list;
  586. return last + 1;
  587. }
  588. /*
  589. * We used up all possible max events,
  590. * lets see if somebody freed one.
  591. */
  592. list_for_each_entry(e, &ftrace_event_list, list) {
  593. if (e->type != last + 1)
  594. break;
  595. last++;
  596. }
  597. /* Did we used up all 65 thousand events??? */
  598. if ((last + 1) > FTRACE_MAX_EVENT)
  599. return 0;
  600. *list = &e->list;
  601. return last + 1;
  602. }
  603. void trace_event_read_lock(void)
  604. {
  605. down_read(&trace_event_mutex);
  606. }
  607. void trace_event_read_unlock(void)
  608. {
  609. up_read(&trace_event_mutex);
  610. }
  611. /**
  612. * register_ftrace_event - register output for an event type
  613. * @event: the event type to register
  614. *
  615. * Event types are stored in a hash and this hash is used to
  616. * find a way to print an event. If the @event->type is set
  617. * then it will use that type, otherwise it will assign a
  618. * type to use.
  619. *
  620. * If you assign your own type, please make sure it is added
  621. * to the trace_type enum in trace.h, to avoid collisions
  622. * with the dynamic types.
  623. *
  624. * Returns the event type number or zero on error.
  625. */
  626. int register_ftrace_event(struct trace_event *event)
  627. {
  628. unsigned key;
  629. int ret = 0;
  630. down_write(&trace_event_mutex);
  631. if (WARN_ON(!event))
  632. goto out;
  633. if (WARN_ON(!event->funcs))
  634. goto out;
  635. INIT_LIST_HEAD(&event->list);
  636. if (!event->type) {
  637. struct list_head *list = NULL;
  638. if (next_event_type > FTRACE_MAX_EVENT) {
  639. event->type = trace_search_list(&list);
  640. if (!event->type)
  641. goto out;
  642. } else {
  643. event->type = next_event_type++;
  644. list = &ftrace_event_list;
  645. }
  646. if (WARN_ON(ftrace_find_event(event->type)))
  647. goto out;
  648. list_add_tail(&event->list, list);
  649. } else if (event->type > __TRACE_LAST_TYPE) {
  650. printk(KERN_WARNING "Need to add type to trace.h\n");
  651. WARN_ON(1);
  652. goto out;
  653. } else {
  654. /* Is this event already used */
  655. if (ftrace_find_event(event->type))
  656. goto out;
  657. }
  658. if (event->funcs->trace == NULL)
  659. event->funcs->trace = trace_nop_print;
  660. if (event->funcs->raw == NULL)
  661. event->funcs->raw = trace_nop_print;
  662. if (event->funcs->hex == NULL)
  663. event->funcs->hex = trace_nop_print;
  664. if (event->funcs->binary == NULL)
  665. event->funcs->binary = trace_nop_print;
  666. key = event->type & (EVENT_HASHSIZE - 1);
  667. hlist_add_head(&event->node, &event_hash[key]);
  668. ret = event->type;
  669. out:
  670. up_write(&trace_event_mutex);
  671. return ret;
  672. }
  673. EXPORT_SYMBOL_GPL(register_ftrace_event);
  674. /*
  675. * Used by module code with the trace_event_mutex held for write.
  676. */
  677. int __unregister_ftrace_event(struct trace_event *event)
  678. {
  679. hlist_del(&event->node);
  680. list_del(&event->list);
  681. return 0;
  682. }
  683. /**
  684. * unregister_ftrace_event - remove a no longer used event
  685. * @event: the event to remove
  686. */
  687. int unregister_ftrace_event(struct trace_event *event)
  688. {
  689. down_write(&trace_event_mutex);
  690. __unregister_ftrace_event(event);
  691. up_write(&trace_event_mutex);
  692. return 0;
  693. }
  694. EXPORT_SYMBOL_GPL(unregister_ftrace_event);
  695. /*
  696. * Standard events
  697. */
  698. enum print_line_t trace_nop_print(struct trace_iterator *iter, int flags,
  699. struct trace_event *event)
  700. {
  701. if (!trace_seq_printf(&iter->seq, "type: %d\n", iter->ent->type))
  702. return TRACE_TYPE_PARTIAL_LINE;
  703. return TRACE_TYPE_HANDLED;
  704. }
  705. /* TRACE_FN */
  706. static enum print_line_t trace_fn_trace(struct trace_iterator *iter, int flags,
  707. struct trace_event *event)
  708. {
  709. struct ftrace_entry *field;
  710. struct trace_seq *s = &iter->seq;
  711. trace_assign_type(field, iter->ent);
  712. if (!seq_print_ip_sym(s, field->ip, flags))
  713. goto partial;
  714. if ((flags & TRACE_ITER_PRINT_PARENT) && field->parent_ip) {
  715. if (!trace_seq_printf(s, " <-"))
  716. goto partial;
  717. if (!seq_print_ip_sym(s,
  718. field->parent_ip,
  719. flags))
  720. goto partial;
  721. }
  722. if (!trace_seq_printf(s, "\n"))
  723. goto partial;
  724. return TRACE_TYPE_HANDLED;
  725. partial:
  726. return TRACE_TYPE_PARTIAL_LINE;
  727. }
  728. static enum print_line_t trace_fn_raw(struct trace_iterator *iter, int flags,
  729. struct trace_event *event)
  730. {
  731. struct ftrace_entry *field;
  732. trace_assign_type(field, iter->ent);
  733. if (!trace_seq_printf(&iter->seq, "%lx %lx\n",
  734. field->ip,
  735. field->parent_ip))
  736. return TRACE_TYPE_PARTIAL_LINE;
  737. return TRACE_TYPE_HANDLED;
  738. }
  739. static enum print_line_t trace_fn_hex(struct trace_iterator *iter, int flags,
  740. struct trace_event *event)
  741. {
  742. struct ftrace_entry *field;
  743. struct trace_seq *s = &iter->seq;
  744. trace_assign_type(field, iter->ent);
  745. SEQ_PUT_HEX_FIELD_RET(s, field->ip);
  746. SEQ_PUT_HEX_FIELD_RET(s, field->parent_ip);
  747. return TRACE_TYPE_HANDLED;
  748. }
  749. static enum print_line_t trace_fn_bin(struct trace_iterator *iter, int flags,
  750. struct trace_event *event)
  751. {
  752. struct ftrace_entry *field;
  753. struct trace_seq *s = &iter->seq;
  754. trace_assign_type(field, iter->ent);
  755. SEQ_PUT_FIELD_RET(s, field->ip);
  756. SEQ_PUT_FIELD_RET(s, field->parent_ip);
  757. return TRACE_TYPE_HANDLED;
  758. }
  759. static struct trace_event_functions trace_fn_funcs = {
  760. .trace = trace_fn_trace,
  761. .raw = trace_fn_raw,
  762. .hex = trace_fn_hex,
  763. .binary = trace_fn_bin,
  764. };
  765. static struct trace_event trace_fn_event = {
  766. .type = TRACE_FN,
  767. .funcs = &trace_fn_funcs,
  768. };
  769. /* TRACE_CTX an TRACE_WAKE */
  770. static enum print_line_t trace_ctxwake_print(struct trace_iterator *iter,
  771. char *delim)
  772. {
  773. struct ctx_switch_entry *field;
  774. char comm[TASK_COMM_LEN];
  775. int S, T;
  776. trace_assign_type(field, iter->ent);
  777. T = task_state_char(field->next_state);
  778. S = task_state_char(field->prev_state);
  779. trace_find_cmdline(field->next_pid, comm);
  780. if (!trace_seq_printf(&iter->seq,
  781. " %5d:%3d:%c %s [%03d] %5d:%3d:%c %s\n",
  782. field->prev_pid,
  783. field->prev_prio,
  784. S, delim,
  785. field->next_cpu,
  786. field->next_pid,
  787. field->next_prio,
  788. T, comm))
  789. return TRACE_TYPE_PARTIAL_LINE;
  790. return TRACE_TYPE_HANDLED;
  791. }
  792. static enum print_line_t trace_ctx_print(struct trace_iterator *iter, int flags,
  793. struct trace_event *event)
  794. {
  795. return trace_ctxwake_print(iter, "==>");
  796. }
  797. static enum print_line_t trace_wake_print(struct trace_iterator *iter,
  798. int flags, struct trace_event *event)
  799. {
  800. return trace_ctxwake_print(iter, " +");
  801. }
  802. static int trace_ctxwake_raw(struct trace_iterator *iter, char S)
  803. {
  804. struct ctx_switch_entry *field;
  805. int T;
  806. trace_assign_type(field, iter->ent);
  807. if (!S)
  808. S = task_state_char(field->prev_state);
  809. T = task_state_char(field->next_state);
  810. if (!trace_seq_printf(&iter->seq, "%d %d %c %d %d %d %c\n",
  811. field->prev_pid,
  812. field->prev_prio,
  813. S,
  814. field->next_cpu,
  815. field->next_pid,
  816. field->next_prio,
  817. T))
  818. return TRACE_TYPE_PARTIAL_LINE;
  819. return TRACE_TYPE_HANDLED;
  820. }
  821. static enum print_line_t trace_ctx_raw(struct trace_iterator *iter, int flags,
  822. struct trace_event *event)
  823. {
  824. return trace_ctxwake_raw(iter, 0);
  825. }
  826. static enum print_line_t trace_wake_raw(struct trace_iterator *iter, int flags,
  827. struct trace_event *event)
  828. {
  829. return trace_ctxwake_raw(iter, '+');
  830. }
  831. static int trace_ctxwake_hex(struct trace_iterator *iter, char S)
  832. {
  833. struct ctx_switch_entry *field;
  834. struct trace_seq *s = &iter->seq;
  835. int T;
  836. trace_assign_type(field, iter->ent);
  837. if (!S)
  838. S = task_state_char(field->prev_state);
  839. T = task_state_char(field->next_state);
  840. SEQ_PUT_HEX_FIELD_RET(s, field->prev_pid);
  841. SEQ_PUT_HEX_FIELD_RET(s, field->prev_prio);
  842. SEQ_PUT_HEX_FIELD_RET(s, S);
  843. SEQ_PUT_HEX_FIELD_RET(s, field->next_cpu);
  844. SEQ_PUT_HEX_FIELD_RET(s, field->next_pid);
  845. SEQ_PUT_HEX_FIELD_RET(s, field->next_prio);
  846. SEQ_PUT_HEX_FIELD_RET(s, T);
  847. return TRACE_TYPE_HANDLED;
  848. }
  849. static enum print_line_t trace_ctx_hex(struct trace_iterator *iter, int flags,
  850. struct trace_event *event)
  851. {
  852. return trace_ctxwake_hex(iter, 0);
  853. }
  854. static enum print_line_t trace_wake_hex(struct trace_iterator *iter, int flags,
  855. struct trace_event *event)
  856. {
  857. return trace_ctxwake_hex(iter, '+');
  858. }
  859. static enum print_line_t trace_ctxwake_bin(struct trace_iterator *iter,
  860. int flags, struct trace_event *event)
  861. {
  862. struct ctx_switch_entry *field;
  863. struct trace_seq *s = &iter->seq;
  864. trace_assign_type(field, iter->ent);
  865. SEQ_PUT_FIELD_RET(s, field->prev_pid);
  866. SEQ_PUT_FIELD_RET(s, field->prev_prio);
  867. SEQ_PUT_FIELD_RET(s, field->prev_state);
  868. SEQ_PUT_FIELD_RET(s, field->next_pid);
  869. SEQ_PUT_FIELD_RET(s, field->next_prio);
  870. SEQ_PUT_FIELD_RET(s, field->next_state);
  871. return TRACE_TYPE_HANDLED;
  872. }
  873. static struct trace_event_functions trace_ctx_funcs = {
  874. .trace = trace_ctx_print,
  875. .raw = trace_ctx_raw,
  876. .hex = trace_ctx_hex,
  877. .binary = trace_ctxwake_bin,
  878. };
  879. static struct trace_event trace_ctx_event = {
  880. .type = TRACE_CTX,
  881. .funcs = &trace_ctx_funcs,
  882. };
  883. static struct trace_event_functions trace_wake_funcs = {
  884. .trace = trace_wake_print,
  885. .raw = trace_wake_raw,
  886. .hex = trace_wake_hex,
  887. .binary = trace_ctxwake_bin,
  888. };
  889. static struct trace_event trace_wake_event = {
  890. .type = TRACE_WAKE,
  891. .funcs = &trace_wake_funcs,
  892. };
  893. /* TRACE_STACK */
  894. static enum print_line_t trace_stack_print(struct trace_iterator *iter,
  895. int flags, struct trace_event *event)
  896. {
  897. struct stack_entry *field;
  898. struct trace_seq *s = &iter->seq;
  899. unsigned long *p;
  900. unsigned long *end;
  901. trace_assign_type(field, iter->ent);
  902. end = (unsigned long *)((long)iter->ent + iter->ent_size);
  903. if (!trace_seq_puts(s, "<stack trace>\n"))
  904. goto partial;
  905. for (p = field->caller; p && *p != ULONG_MAX && p < end; p++) {
  906. if (!trace_seq_puts(s, " => "))
  907. goto partial;
  908. if (!seq_print_ip_sym(s, *p, flags))
  909. goto partial;
  910. if (!trace_seq_puts(s, "\n"))
  911. goto partial;
  912. }
  913. return TRACE_TYPE_HANDLED;
  914. partial:
  915. return TRACE_TYPE_PARTIAL_LINE;
  916. }
  917. static struct trace_event_functions trace_stack_funcs = {
  918. .trace = trace_stack_print,
  919. };
  920. static struct trace_event trace_stack_event = {
  921. .type = TRACE_STACK,
  922. .funcs = &trace_stack_funcs,
  923. };
  924. /* TRACE_USER_STACK */
  925. static enum print_line_t trace_user_stack_print(struct trace_iterator *iter,
  926. int flags, struct trace_event *event)
  927. {
  928. struct userstack_entry *field;
  929. struct trace_seq *s = &iter->seq;
  930. trace_assign_type(field, iter->ent);
  931. if (!trace_seq_puts(s, "<user stack trace>\n"))
  932. goto partial;
  933. if (!seq_print_userip_objs(field, s, flags))
  934. goto partial;
  935. return TRACE_TYPE_HANDLED;
  936. partial:
  937. return TRACE_TYPE_PARTIAL_LINE;
  938. }
  939. static struct trace_event_functions trace_user_stack_funcs = {
  940. .trace = trace_user_stack_print,
  941. };
  942. static struct trace_event trace_user_stack_event = {
  943. .type = TRACE_USER_STACK,
  944. .funcs = &trace_user_stack_funcs,
  945. };
  946. /* TRACE_BPRINT */
  947. static enum print_line_t
  948. trace_bprint_print(struct trace_iterator *iter, int flags,
  949. struct trace_event *event)
  950. {
  951. struct trace_entry *entry = iter->ent;
  952. struct trace_seq *s = &iter->seq;
  953. struct bprint_entry *field;
  954. trace_assign_type(field, entry);
  955. if (!seq_print_ip_sym(s, field->ip, flags))
  956. goto partial;
  957. if (!trace_seq_puts(s, ": "))
  958. goto partial;
  959. if (!trace_seq_bprintf(s, field->fmt, field->buf))
  960. goto partial;
  961. return TRACE_TYPE_HANDLED;
  962. partial:
  963. return TRACE_TYPE_PARTIAL_LINE;
  964. }
  965. static enum print_line_t
  966. trace_bprint_raw(struct trace_iterator *iter, int flags,
  967. struct trace_event *event)
  968. {
  969. struct bprint_entry *field;
  970. struct trace_seq *s = &iter->seq;
  971. trace_assign_type(field, iter->ent);
  972. if (!trace_seq_printf(s, ": %lx : ", field->ip))
  973. goto partial;
  974. if (!trace_seq_bprintf(s, field->fmt, field->buf))
  975. goto partial;
  976. return TRACE_TYPE_HANDLED;
  977. partial:
  978. return TRACE_TYPE_PARTIAL_LINE;
  979. }
  980. static struct trace_event_functions trace_bprint_funcs = {
  981. .trace = trace_bprint_print,
  982. .raw = trace_bprint_raw,
  983. };
  984. static struct trace_event trace_bprint_event = {
  985. .type = TRACE_BPRINT,
  986. .funcs = &trace_bprint_funcs,
  987. };
  988. /* TRACE_PRINT */
  989. static enum print_line_t trace_print_print(struct trace_iterator *iter,
  990. int flags, struct trace_event *event)
  991. {
  992. struct print_entry *field;
  993. struct trace_seq *s = &iter->seq;
  994. trace_assign_type(field, iter->ent);
  995. if (!seq_print_ip_sym(s, field->ip, flags))
  996. goto partial;
  997. if (!trace_seq_printf(s, ": %s", field->buf))
  998. goto partial;
  999. return TRACE_TYPE_HANDLED;
  1000. partial:
  1001. return TRACE_TYPE_PARTIAL_LINE;
  1002. }
  1003. static enum print_line_t trace_print_raw(struct trace_iterator *iter, int flags,
  1004. struct trace_event *event)
  1005. {
  1006. struct print_entry *field;
  1007. trace_assign_type(field, iter->ent);
  1008. if (!trace_seq_printf(&iter->seq, "# %lx %s", field->ip, field->buf))
  1009. goto partial;
  1010. return TRACE_TYPE_HANDLED;
  1011. partial:
  1012. return TRACE_TYPE_PARTIAL_LINE;
  1013. }
  1014. static struct trace_event_functions trace_print_funcs = {
  1015. .trace = trace_print_print,
  1016. .raw = trace_print_raw,
  1017. };
  1018. static struct trace_event trace_print_event = {
  1019. .type = TRACE_PRINT,
  1020. .funcs = &trace_print_funcs,
  1021. };
  1022. static struct trace_event *events[] __initdata = {
  1023. &trace_fn_event,
  1024. &trace_ctx_event,
  1025. &trace_wake_event,
  1026. &trace_stack_event,
  1027. &trace_user_stack_event,
  1028. &trace_bprint_event,
  1029. &trace_print_event,
  1030. NULL
  1031. };
  1032. __init static int init_events(void)
  1033. {
  1034. struct trace_event *event;
  1035. int i, ret;
  1036. for (i = 0; events[i]; i++) {
  1037. event = events[i];
  1038. ret = register_ftrace_event(event);
  1039. if (!ret) {
  1040. printk(KERN_WARNING "event %d failed to register\n",
  1041. event->type);
  1042. WARN_ON_ONCE(1);
  1043. }
  1044. }
  1045. return 0;
  1046. }
  1047. device_initcall(init_events);