trace_output.c 27 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, 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;
  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 (p->len && delim)
  247. trace_seq_puts(p, delim);
  248. trace_seq_puts(p, str);
  249. }
  250. /* check for left over flags */
  251. if (flags) {
  252. if (p->len && delim)
  253. trace_seq_puts(p, delim);
  254. trace_seq_printf(p, "0x%lx", flags);
  255. }
  256. trace_seq_putc(p, 0);
  257. return ret;
  258. }
  259. EXPORT_SYMBOL(ftrace_print_flags_seq);
  260. const char *
  261. ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val,
  262. const struct trace_print_flags *symbol_array)
  263. {
  264. int i;
  265. const char *ret = p->buffer + p->len;
  266. for (i = 0; symbol_array[i].name; i++) {
  267. if (val != symbol_array[i].mask)
  268. continue;
  269. trace_seq_puts(p, symbol_array[i].name);
  270. break;
  271. }
  272. if (!p->len)
  273. trace_seq_printf(p, "0x%lx", val);
  274. trace_seq_putc(p, 0);
  275. return ret;
  276. }
  277. EXPORT_SYMBOL(ftrace_print_symbols_seq);
  278. const char *
  279. ftrace_print_hex_seq(struct trace_seq *p, const unsigned char *buf, int buf_len)
  280. {
  281. int i;
  282. const char *ret = p->buffer + p->len;
  283. for (i = 0; i < buf_len; i++)
  284. trace_seq_printf(p, "%s%2.2x", i == 0 ? "" : " ", buf[i]);
  285. trace_seq_putc(p, 0);
  286. return ret;
  287. }
  288. EXPORT_SYMBOL(ftrace_print_hex_seq);
  289. #ifdef CONFIG_KRETPROBES
  290. static inline const char *kretprobed(const char *name)
  291. {
  292. static const char tramp_name[] = "kretprobe_trampoline";
  293. int size = sizeof(tramp_name);
  294. if (strncmp(tramp_name, name, size) == 0)
  295. return "[unknown/kretprobe'd]";
  296. return name;
  297. }
  298. #else
  299. static inline const char *kretprobed(const char *name)
  300. {
  301. return name;
  302. }
  303. #endif /* CONFIG_KRETPROBES */
  304. static int
  305. seq_print_sym_short(struct trace_seq *s, const char *fmt, unsigned long address)
  306. {
  307. #ifdef CONFIG_KALLSYMS
  308. char str[KSYM_SYMBOL_LEN];
  309. const char *name;
  310. kallsyms_lookup(address, NULL, NULL, NULL, str);
  311. name = kretprobed(str);
  312. return trace_seq_printf(s, fmt, name);
  313. #endif
  314. return 1;
  315. }
  316. static int
  317. seq_print_sym_offset(struct trace_seq *s, const char *fmt,
  318. unsigned long address)
  319. {
  320. #ifdef CONFIG_KALLSYMS
  321. char str[KSYM_SYMBOL_LEN];
  322. const char *name;
  323. sprint_symbol(str, address);
  324. name = kretprobed(str);
  325. return trace_seq_printf(s, fmt, name);
  326. #endif
  327. return 1;
  328. }
  329. #ifndef CONFIG_64BIT
  330. # define IP_FMT "%08lx"
  331. #else
  332. # define IP_FMT "%016lx"
  333. #endif
  334. int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm,
  335. unsigned long ip, unsigned long sym_flags)
  336. {
  337. struct file *file = NULL;
  338. unsigned long vmstart = 0;
  339. int ret = 1;
  340. if (s->full)
  341. return 0;
  342. if (mm) {
  343. const struct vm_area_struct *vma;
  344. down_read(&mm->mmap_sem);
  345. vma = find_vma(mm, ip);
  346. if (vma) {
  347. file = vma->vm_file;
  348. vmstart = vma->vm_start;
  349. }
  350. if (file) {
  351. ret = trace_seq_path(s, &file->f_path);
  352. if (ret)
  353. ret = trace_seq_printf(s, "[+0x%lx]",
  354. ip - vmstart);
  355. }
  356. up_read(&mm->mmap_sem);
  357. }
  358. if (ret && ((sym_flags & TRACE_ITER_SYM_ADDR) || !file))
  359. ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
  360. return ret;
  361. }
  362. int
  363. seq_print_userip_objs(const struct userstack_entry *entry, struct trace_seq *s,
  364. unsigned long sym_flags)
  365. {
  366. struct mm_struct *mm = NULL;
  367. int ret = 1;
  368. unsigned int i;
  369. if (trace_flags & TRACE_ITER_SYM_USEROBJ) {
  370. struct task_struct *task;
  371. /*
  372. * we do the lookup on the thread group leader,
  373. * since individual threads might have already quit!
  374. */
  375. rcu_read_lock();
  376. task = find_task_by_vpid(entry->tgid);
  377. if (task)
  378. mm = get_task_mm(task);
  379. rcu_read_unlock();
  380. }
  381. for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
  382. unsigned long ip = entry->caller[i];
  383. if (ip == ULONG_MAX || !ret)
  384. break;
  385. if (ret)
  386. ret = trace_seq_puts(s, " => ");
  387. if (!ip) {
  388. if (ret)
  389. ret = trace_seq_puts(s, "??");
  390. if (ret)
  391. ret = trace_seq_puts(s, "\n");
  392. continue;
  393. }
  394. if (!ret)
  395. break;
  396. if (ret)
  397. ret = seq_print_user_ip(s, mm, ip, sym_flags);
  398. ret = trace_seq_puts(s, "\n");
  399. }
  400. if (mm)
  401. mmput(mm);
  402. return ret;
  403. }
  404. int
  405. seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
  406. {
  407. int ret;
  408. if (!ip)
  409. return trace_seq_printf(s, "0");
  410. if (sym_flags & TRACE_ITER_SYM_OFFSET)
  411. ret = seq_print_sym_offset(s, "%s", ip);
  412. else
  413. ret = seq_print_sym_short(s, "%s", ip);
  414. if (!ret)
  415. return 0;
  416. if (sym_flags & TRACE_ITER_SYM_ADDR)
  417. ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
  418. return ret;
  419. }
  420. /**
  421. * trace_print_lat_fmt - print the irq, preempt and lockdep fields
  422. * @s: trace seq struct to write to
  423. * @entry: The trace entry field from the ring buffer
  424. *
  425. * Prints the generic fields of irqs off, in hard or softirq, preempt
  426. * count.
  427. */
  428. int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
  429. {
  430. char hardsoft_irq;
  431. char need_resched;
  432. char irqs_off;
  433. int hardirq;
  434. int softirq;
  435. int ret;
  436. hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
  437. softirq = entry->flags & TRACE_FLAG_SOFTIRQ;
  438. irqs_off =
  439. (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' :
  440. (entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ? 'X' :
  441. '.';
  442. need_resched =
  443. (entry->flags & TRACE_FLAG_NEED_RESCHED) ? 'N' : '.';
  444. hardsoft_irq =
  445. (hardirq && softirq) ? 'H' :
  446. hardirq ? 'h' :
  447. softirq ? 's' :
  448. '.';
  449. if (!trace_seq_printf(s, "%c%c%c",
  450. irqs_off, need_resched, hardsoft_irq))
  451. return 0;
  452. if (entry->preempt_count)
  453. ret = trace_seq_printf(s, "%x", entry->preempt_count);
  454. else
  455. ret = trace_seq_putc(s, '.');
  456. return ret;
  457. }
  458. static int
  459. lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
  460. {
  461. char comm[TASK_COMM_LEN];
  462. trace_find_cmdline(entry->pid, comm);
  463. if (!trace_seq_printf(s, "%8.8s-%-5d %3d",
  464. comm, entry->pid, cpu))
  465. return 0;
  466. return trace_print_lat_fmt(s, entry);
  467. }
  468. static unsigned long preempt_mark_thresh = 100;
  469. static int
  470. lat_print_timestamp(struct trace_seq *s, u64 abs_usecs,
  471. unsigned long rel_usecs)
  472. {
  473. return trace_seq_printf(s, " %4lldus%c: ", abs_usecs,
  474. rel_usecs > preempt_mark_thresh ? '!' :
  475. rel_usecs > 1 ? '+' : ' ');
  476. }
  477. int trace_print_context(struct trace_iterator *iter)
  478. {
  479. struct trace_seq *s = &iter->seq;
  480. struct trace_entry *entry = iter->ent;
  481. unsigned long long t = ns2usecs(iter->ts);
  482. unsigned long usec_rem = do_div(t, USEC_PER_SEC);
  483. unsigned long secs = (unsigned long)t;
  484. char comm[TASK_COMM_LEN];
  485. trace_find_cmdline(entry->pid, comm);
  486. return trace_seq_printf(s, "%16s-%-5d [%03d] %5lu.%06lu: ",
  487. comm, entry->pid, iter->cpu, secs, usec_rem);
  488. }
  489. int trace_print_lat_context(struct trace_iterator *iter)
  490. {
  491. u64 next_ts;
  492. int ret;
  493. struct trace_seq *s = &iter->seq;
  494. struct trace_entry *entry = iter->ent,
  495. *next_entry = trace_find_next_entry(iter, NULL,
  496. &next_ts);
  497. unsigned long verbose = (trace_flags & TRACE_ITER_VERBOSE);
  498. unsigned long abs_usecs = ns2usecs(iter->ts - iter->tr->time_start);
  499. unsigned long rel_usecs;
  500. if (!next_entry)
  501. next_ts = iter->ts;
  502. rel_usecs = ns2usecs(next_ts - iter->ts);
  503. if (verbose) {
  504. char comm[TASK_COMM_LEN];
  505. trace_find_cmdline(entry->pid, comm);
  506. ret = trace_seq_printf(s, "%16s %5d %3d %d %08x %08lx [%08llx]"
  507. " %ld.%03ldms (+%ld.%03ldms): ", comm,
  508. entry->pid, iter->cpu, entry->flags,
  509. entry->preempt_count, iter->idx,
  510. ns2usecs(iter->ts),
  511. abs_usecs / USEC_PER_MSEC,
  512. abs_usecs % USEC_PER_MSEC,
  513. rel_usecs / USEC_PER_MSEC,
  514. rel_usecs % USEC_PER_MSEC);
  515. } else {
  516. ret = lat_print_generic(s, entry, iter->cpu);
  517. if (ret)
  518. ret = lat_print_timestamp(s, abs_usecs, rel_usecs);
  519. }
  520. return ret;
  521. }
  522. static const char state_to_char[] = TASK_STATE_TO_CHAR_STR;
  523. static int task_state_char(unsigned long state)
  524. {
  525. int bit = state ? __ffs(state) + 1 : 0;
  526. return bit < sizeof(state_to_char) - 1 ? state_to_char[bit] : '?';
  527. }
  528. /**
  529. * ftrace_find_event - find a registered event
  530. * @type: the type of event to look for
  531. *
  532. * Returns an event of type @type otherwise NULL
  533. * Called with trace_event_read_lock() held.
  534. */
  535. struct trace_event *ftrace_find_event(int type)
  536. {
  537. struct trace_event *event;
  538. struct hlist_node *n;
  539. unsigned key;
  540. key = type & (EVENT_HASHSIZE - 1);
  541. hlist_for_each_entry(event, n, &event_hash[key], node) {
  542. if (event->type == type)
  543. return event;
  544. }
  545. return NULL;
  546. }
  547. static LIST_HEAD(ftrace_event_list);
  548. static int trace_search_list(struct list_head **list)
  549. {
  550. struct trace_event *e;
  551. int last = __TRACE_LAST_TYPE;
  552. if (list_empty(&ftrace_event_list)) {
  553. *list = &ftrace_event_list;
  554. return last + 1;
  555. }
  556. /*
  557. * We used up all possible max events,
  558. * lets see if somebody freed one.
  559. */
  560. list_for_each_entry(e, &ftrace_event_list, list) {
  561. if (e->type != last + 1)
  562. break;
  563. last++;
  564. }
  565. /* Did we used up all 65 thousand events??? */
  566. if ((last + 1) > FTRACE_MAX_EVENT)
  567. return 0;
  568. *list = &e->list;
  569. return last + 1;
  570. }
  571. void trace_event_read_lock(void)
  572. {
  573. down_read(&trace_event_mutex);
  574. }
  575. void trace_event_read_unlock(void)
  576. {
  577. up_read(&trace_event_mutex);
  578. }
  579. /**
  580. * register_ftrace_event - register output for an event type
  581. * @event: the event type to register
  582. *
  583. * Event types are stored in a hash and this hash is used to
  584. * find a way to print an event. If the @event->type is set
  585. * then it will use that type, otherwise it will assign a
  586. * type to use.
  587. *
  588. * If you assign your own type, please make sure it is added
  589. * to the trace_type enum in trace.h, to avoid collisions
  590. * with the dynamic types.
  591. *
  592. * Returns the event type number or zero on error.
  593. */
  594. int register_ftrace_event(struct trace_event *event)
  595. {
  596. unsigned key;
  597. int ret = 0;
  598. down_write(&trace_event_mutex);
  599. if (WARN_ON(!event))
  600. goto out;
  601. if (WARN_ON(!event->funcs))
  602. goto out;
  603. INIT_LIST_HEAD(&event->list);
  604. if (!event->type) {
  605. struct list_head *list = NULL;
  606. if (next_event_type > FTRACE_MAX_EVENT) {
  607. event->type = trace_search_list(&list);
  608. if (!event->type)
  609. goto out;
  610. } else {
  611. event->type = next_event_type++;
  612. list = &ftrace_event_list;
  613. }
  614. if (WARN_ON(ftrace_find_event(event->type)))
  615. goto out;
  616. list_add_tail(&event->list, list);
  617. } else if (event->type > __TRACE_LAST_TYPE) {
  618. printk(KERN_WARNING "Need to add type to trace.h\n");
  619. WARN_ON(1);
  620. goto out;
  621. } else {
  622. /* Is this event already used */
  623. if (ftrace_find_event(event->type))
  624. goto out;
  625. }
  626. if (event->funcs->trace == NULL)
  627. event->funcs->trace = trace_nop_print;
  628. if (event->funcs->raw == NULL)
  629. event->funcs->raw = trace_nop_print;
  630. if (event->funcs->hex == NULL)
  631. event->funcs->hex = trace_nop_print;
  632. if (event->funcs->binary == NULL)
  633. event->funcs->binary = trace_nop_print;
  634. key = event->type & (EVENT_HASHSIZE - 1);
  635. hlist_add_head(&event->node, &event_hash[key]);
  636. ret = event->type;
  637. out:
  638. up_write(&trace_event_mutex);
  639. return ret;
  640. }
  641. EXPORT_SYMBOL_GPL(register_ftrace_event);
  642. /*
  643. * Used by module code with the trace_event_mutex held for write.
  644. */
  645. int __unregister_ftrace_event(struct trace_event *event)
  646. {
  647. hlist_del(&event->node);
  648. list_del(&event->list);
  649. return 0;
  650. }
  651. /**
  652. * unregister_ftrace_event - remove a no longer used event
  653. * @event: the event to remove
  654. */
  655. int unregister_ftrace_event(struct trace_event *event)
  656. {
  657. down_write(&trace_event_mutex);
  658. __unregister_ftrace_event(event);
  659. up_write(&trace_event_mutex);
  660. return 0;
  661. }
  662. EXPORT_SYMBOL_GPL(unregister_ftrace_event);
  663. /*
  664. * Standard events
  665. */
  666. enum print_line_t trace_nop_print(struct trace_iterator *iter, int flags,
  667. struct trace_event *event)
  668. {
  669. return TRACE_TYPE_HANDLED;
  670. }
  671. /* TRACE_FN */
  672. static enum print_line_t trace_fn_trace(struct trace_iterator *iter, int flags,
  673. struct trace_event *event)
  674. {
  675. struct ftrace_entry *field;
  676. struct trace_seq *s = &iter->seq;
  677. trace_assign_type(field, iter->ent);
  678. if (!seq_print_ip_sym(s, field->ip, flags))
  679. goto partial;
  680. if ((flags & TRACE_ITER_PRINT_PARENT) && field->parent_ip) {
  681. if (!trace_seq_printf(s, " <-"))
  682. goto partial;
  683. if (!seq_print_ip_sym(s,
  684. field->parent_ip,
  685. flags))
  686. goto partial;
  687. }
  688. if (!trace_seq_printf(s, "\n"))
  689. goto partial;
  690. return TRACE_TYPE_HANDLED;
  691. partial:
  692. return TRACE_TYPE_PARTIAL_LINE;
  693. }
  694. static enum print_line_t trace_fn_raw(struct trace_iterator *iter, int flags,
  695. struct trace_event *event)
  696. {
  697. struct ftrace_entry *field;
  698. trace_assign_type(field, iter->ent);
  699. if (!trace_seq_printf(&iter->seq, "%lx %lx\n",
  700. field->ip,
  701. field->parent_ip))
  702. return TRACE_TYPE_PARTIAL_LINE;
  703. return TRACE_TYPE_HANDLED;
  704. }
  705. static enum print_line_t trace_fn_hex(struct trace_iterator *iter, int flags,
  706. struct trace_event *event)
  707. {
  708. struct ftrace_entry *field;
  709. struct trace_seq *s = &iter->seq;
  710. trace_assign_type(field, iter->ent);
  711. SEQ_PUT_HEX_FIELD_RET(s, field->ip);
  712. SEQ_PUT_HEX_FIELD_RET(s, field->parent_ip);
  713. return TRACE_TYPE_HANDLED;
  714. }
  715. static enum print_line_t trace_fn_bin(struct trace_iterator *iter, int flags,
  716. struct trace_event *event)
  717. {
  718. struct ftrace_entry *field;
  719. struct trace_seq *s = &iter->seq;
  720. trace_assign_type(field, iter->ent);
  721. SEQ_PUT_FIELD_RET(s, field->ip);
  722. SEQ_PUT_FIELD_RET(s, field->parent_ip);
  723. return TRACE_TYPE_HANDLED;
  724. }
  725. static struct trace_event_functions trace_fn_funcs = {
  726. .trace = trace_fn_trace,
  727. .raw = trace_fn_raw,
  728. .hex = trace_fn_hex,
  729. .binary = trace_fn_bin,
  730. };
  731. static struct trace_event trace_fn_event = {
  732. .type = TRACE_FN,
  733. .funcs = &trace_fn_funcs,
  734. };
  735. /* TRACE_CTX an TRACE_WAKE */
  736. static enum print_line_t trace_ctxwake_print(struct trace_iterator *iter,
  737. char *delim)
  738. {
  739. struct ctx_switch_entry *field;
  740. char comm[TASK_COMM_LEN];
  741. int S, T;
  742. trace_assign_type(field, iter->ent);
  743. T = task_state_char(field->next_state);
  744. S = task_state_char(field->prev_state);
  745. trace_find_cmdline(field->next_pid, comm);
  746. if (!trace_seq_printf(&iter->seq,
  747. " %5d:%3d:%c %s [%03d] %5d:%3d:%c %s\n",
  748. field->prev_pid,
  749. field->prev_prio,
  750. S, delim,
  751. field->next_cpu,
  752. field->next_pid,
  753. field->next_prio,
  754. T, comm))
  755. return TRACE_TYPE_PARTIAL_LINE;
  756. return TRACE_TYPE_HANDLED;
  757. }
  758. static enum print_line_t trace_ctx_print(struct trace_iterator *iter, int flags,
  759. struct trace_event *event)
  760. {
  761. return trace_ctxwake_print(iter, "==>");
  762. }
  763. static enum print_line_t trace_wake_print(struct trace_iterator *iter,
  764. int flags, struct trace_event *event)
  765. {
  766. return trace_ctxwake_print(iter, " +");
  767. }
  768. static int trace_ctxwake_raw(struct trace_iterator *iter, char S)
  769. {
  770. struct ctx_switch_entry *field;
  771. int T;
  772. trace_assign_type(field, iter->ent);
  773. if (!S)
  774. S = task_state_char(field->prev_state);
  775. T = task_state_char(field->next_state);
  776. if (!trace_seq_printf(&iter->seq, "%d %d %c %d %d %d %c\n",
  777. field->prev_pid,
  778. field->prev_prio,
  779. S,
  780. field->next_cpu,
  781. field->next_pid,
  782. field->next_prio,
  783. T))
  784. return TRACE_TYPE_PARTIAL_LINE;
  785. return TRACE_TYPE_HANDLED;
  786. }
  787. static enum print_line_t trace_ctx_raw(struct trace_iterator *iter, int flags,
  788. struct trace_event *event)
  789. {
  790. return trace_ctxwake_raw(iter, 0);
  791. }
  792. static enum print_line_t trace_wake_raw(struct trace_iterator *iter, int flags,
  793. struct trace_event *event)
  794. {
  795. return trace_ctxwake_raw(iter, '+');
  796. }
  797. static int trace_ctxwake_hex(struct trace_iterator *iter, char S)
  798. {
  799. struct ctx_switch_entry *field;
  800. struct trace_seq *s = &iter->seq;
  801. int T;
  802. trace_assign_type(field, iter->ent);
  803. if (!S)
  804. S = task_state_char(field->prev_state);
  805. T = task_state_char(field->next_state);
  806. SEQ_PUT_HEX_FIELD_RET(s, field->prev_pid);
  807. SEQ_PUT_HEX_FIELD_RET(s, field->prev_prio);
  808. SEQ_PUT_HEX_FIELD_RET(s, S);
  809. SEQ_PUT_HEX_FIELD_RET(s, field->next_cpu);
  810. SEQ_PUT_HEX_FIELD_RET(s, field->next_pid);
  811. SEQ_PUT_HEX_FIELD_RET(s, field->next_prio);
  812. SEQ_PUT_HEX_FIELD_RET(s, T);
  813. return TRACE_TYPE_HANDLED;
  814. }
  815. static enum print_line_t trace_ctx_hex(struct trace_iterator *iter, int flags,
  816. struct trace_event *event)
  817. {
  818. return trace_ctxwake_hex(iter, 0);
  819. }
  820. static enum print_line_t trace_wake_hex(struct trace_iterator *iter, int flags,
  821. struct trace_event *event)
  822. {
  823. return trace_ctxwake_hex(iter, '+');
  824. }
  825. static enum print_line_t trace_ctxwake_bin(struct trace_iterator *iter,
  826. int flags, struct trace_event *event)
  827. {
  828. struct ctx_switch_entry *field;
  829. struct trace_seq *s = &iter->seq;
  830. trace_assign_type(field, iter->ent);
  831. SEQ_PUT_FIELD_RET(s, field->prev_pid);
  832. SEQ_PUT_FIELD_RET(s, field->prev_prio);
  833. SEQ_PUT_FIELD_RET(s, field->prev_state);
  834. SEQ_PUT_FIELD_RET(s, field->next_pid);
  835. SEQ_PUT_FIELD_RET(s, field->next_prio);
  836. SEQ_PUT_FIELD_RET(s, field->next_state);
  837. return TRACE_TYPE_HANDLED;
  838. }
  839. static struct trace_event_functions trace_ctx_funcs = {
  840. .trace = trace_ctx_print,
  841. .raw = trace_ctx_raw,
  842. .hex = trace_ctx_hex,
  843. .binary = trace_ctxwake_bin,
  844. };
  845. static struct trace_event trace_ctx_event = {
  846. .type = TRACE_CTX,
  847. .funcs = &trace_ctx_funcs,
  848. };
  849. static struct trace_event_functions trace_wake_funcs = {
  850. .trace = trace_wake_print,
  851. .raw = trace_wake_raw,
  852. .hex = trace_wake_hex,
  853. .binary = trace_ctxwake_bin,
  854. };
  855. static struct trace_event trace_wake_event = {
  856. .type = TRACE_WAKE,
  857. .funcs = &trace_wake_funcs,
  858. };
  859. /* TRACE_STACK */
  860. static enum print_line_t trace_stack_print(struct trace_iterator *iter,
  861. int flags, struct trace_event *event)
  862. {
  863. struct stack_entry *field;
  864. struct trace_seq *s = &iter->seq;
  865. int i;
  866. trace_assign_type(field, iter->ent);
  867. if (!trace_seq_puts(s, "<stack trace>\n"))
  868. goto partial;
  869. for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
  870. if (!field->caller[i] || (field->caller[i] == ULONG_MAX))
  871. break;
  872. if (!trace_seq_puts(s, " => "))
  873. goto partial;
  874. if (!seq_print_ip_sym(s, field->caller[i], flags))
  875. goto partial;
  876. if (!trace_seq_puts(s, "\n"))
  877. goto partial;
  878. }
  879. return TRACE_TYPE_HANDLED;
  880. partial:
  881. return TRACE_TYPE_PARTIAL_LINE;
  882. }
  883. static struct trace_event_functions trace_stack_funcs = {
  884. .trace = trace_stack_print,
  885. };
  886. static struct trace_event trace_stack_event = {
  887. .type = TRACE_STACK,
  888. .funcs = &trace_stack_funcs,
  889. };
  890. /* TRACE_USER_STACK */
  891. static enum print_line_t trace_user_stack_print(struct trace_iterator *iter,
  892. int flags, struct trace_event *event)
  893. {
  894. struct userstack_entry *field;
  895. struct trace_seq *s = &iter->seq;
  896. trace_assign_type(field, iter->ent);
  897. if (!trace_seq_puts(s, "<user stack trace>\n"))
  898. goto partial;
  899. if (!seq_print_userip_objs(field, s, flags))
  900. goto partial;
  901. return TRACE_TYPE_HANDLED;
  902. partial:
  903. return TRACE_TYPE_PARTIAL_LINE;
  904. }
  905. static struct trace_event_functions trace_user_stack_funcs = {
  906. .trace = trace_user_stack_print,
  907. };
  908. static struct trace_event trace_user_stack_event = {
  909. .type = TRACE_USER_STACK,
  910. .funcs = &trace_user_stack_funcs,
  911. };
  912. /* TRACE_BPRINT */
  913. static enum print_line_t
  914. trace_bprint_print(struct trace_iterator *iter, int flags,
  915. struct trace_event *event)
  916. {
  917. struct trace_entry *entry = iter->ent;
  918. struct trace_seq *s = &iter->seq;
  919. struct bprint_entry *field;
  920. trace_assign_type(field, entry);
  921. if (!seq_print_ip_sym(s, field->ip, flags))
  922. goto partial;
  923. if (!trace_seq_puts(s, ": "))
  924. goto partial;
  925. if (!trace_seq_bprintf(s, field->fmt, field->buf))
  926. goto partial;
  927. return TRACE_TYPE_HANDLED;
  928. partial:
  929. return TRACE_TYPE_PARTIAL_LINE;
  930. }
  931. static enum print_line_t
  932. trace_bprint_raw(struct trace_iterator *iter, int flags,
  933. struct trace_event *event)
  934. {
  935. struct bprint_entry *field;
  936. struct trace_seq *s = &iter->seq;
  937. trace_assign_type(field, iter->ent);
  938. if (!trace_seq_printf(s, ": %lx : ", field->ip))
  939. goto partial;
  940. if (!trace_seq_bprintf(s, field->fmt, field->buf))
  941. goto partial;
  942. return TRACE_TYPE_HANDLED;
  943. partial:
  944. return TRACE_TYPE_PARTIAL_LINE;
  945. }
  946. static struct trace_event_functions trace_bprint_funcs = {
  947. .trace = trace_bprint_print,
  948. .raw = trace_bprint_raw,
  949. };
  950. static struct trace_event trace_bprint_event = {
  951. .type = TRACE_BPRINT,
  952. .funcs = &trace_bprint_funcs,
  953. };
  954. /* TRACE_PRINT */
  955. static enum print_line_t trace_print_print(struct trace_iterator *iter,
  956. int flags, struct trace_event *event)
  957. {
  958. struct print_entry *field;
  959. struct trace_seq *s = &iter->seq;
  960. trace_assign_type(field, iter->ent);
  961. if (!seq_print_ip_sym(s, field->ip, flags))
  962. goto partial;
  963. if (!trace_seq_printf(s, ": %s", 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 trace_print_raw(struct trace_iterator *iter, int flags,
  970. struct trace_event *event)
  971. {
  972. struct print_entry *field;
  973. trace_assign_type(field, iter->ent);
  974. if (!trace_seq_printf(&iter->seq, "# %lx %s", field->ip, 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_print_funcs = {
  981. .trace = trace_print_print,
  982. .raw = trace_print_raw,
  983. };
  984. static struct trace_event trace_print_event = {
  985. .type = TRACE_PRINT,
  986. .funcs = &trace_print_funcs,
  987. };
  988. static struct trace_event *events[] __initdata = {
  989. &trace_fn_event,
  990. &trace_ctx_event,
  991. &trace_wake_event,
  992. &trace_stack_event,
  993. &trace_user_stack_event,
  994. &trace_bprint_event,
  995. &trace_print_event,
  996. NULL
  997. };
  998. __init static int init_events(void)
  999. {
  1000. struct trace_event *event;
  1001. int i, ret;
  1002. for (i = 0; events[i]; i++) {
  1003. event = events[i];
  1004. ret = register_ftrace_event(event);
  1005. if (!ret) {
  1006. printk(KERN_WARNING "event %d failed to register\n",
  1007. event->type);
  1008. WARN_ON_ONCE(1);
  1009. }
  1010. }
  1011. return 0;
  1012. }
  1013. device_initcall(init_events);