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. int hardirq, softirq;
  431. int ret;
  432. hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
  433. softirq = entry->flags & TRACE_FLAG_SOFTIRQ;
  434. if (!trace_seq_printf(s, "%c%c%c",
  435. (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' :
  436. (entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ?
  437. 'X' : '.',
  438. (entry->flags & TRACE_FLAG_NEED_RESCHED) ?
  439. 'N' : '.',
  440. (hardirq && softirq) ? 'H' :
  441. hardirq ? 'h' : softirq ? 's' : '.'))
  442. return 0;
  443. if (entry->preempt_count)
  444. ret = trace_seq_printf(s, "%x", entry->preempt_count);
  445. else
  446. ret = trace_seq_putc(s, '.');
  447. return ret;
  448. }
  449. static int
  450. lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
  451. {
  452. char comm[TASK_COMM_LEN];
  453. trace_find_cmdline(entry->pid, comm);
  454. if (!trace_seq_printf(s, "%8.8s-%-5d %3d",
  455. comm, entry->pid, cpu))
  456. return 0;
  457. return trace_print_lat_fmt(s, entry);
  458. }
  459. static unsigned long preempt_mark_thresh = 100;
  460. static int
  461. lat_print_timestamp(struct trace_seq *s, u64 abs_usecs,
  462. unsigned long rel_usecs)
  463. {
  464. return trace_seq_printf(s, " %4lldus%c: ", abs_usecs,
  465. rel_usecs > preempt_mark_thresh ? '!' :
  466. rel_usecs > 1 ? '+' : ' ');
  467. }
  468. int trace_print_context(struct trace_iterator *iter)
  469. {
  470. struct trace_seq *s = &iter->seq;
  471. struct trace_entry *entry = iter->ent;
  472. unsigned long long t = ns2usecs(iter->ts);
  473. unsigned long usec_rem = do_div(t, USEC_PER_SEC);
  474. unsigned long secs = (unsigned long)t;
  475. char comm[TASK_COMM_LEN];
  476. trace_find_cmdline(entry->pid, comm);
  477. return trace_seq_printf(s, "%16s-%-5d [%03d] %5lu.%06lu: ",
  478. comm, entry->pid, iter->cpu, secs, usec_rem);
  479. }
  480. int trace_print_lat_context(struct trace_iterator *iter)
  481. {
  482. u64 next_ts;
  483. int ret;
  484. struct trace_seq *s = &iter->seq;
  485. struct trace_entry *entry = iter->ent,
  486. *next_entry = trace_find_next_entry(iter, NULL,
  487. &next_ts);
  488. unsigned long verbose = (trace_flags & TRACE_ITER_VERBOSE);
  489. unsigned long abs_usecs = ns2usecs(iter->ts - iter->tr->time_start);
  490. unsigned long rel_usecs;
  491. if (!next_entry)
  492. next_ts = iter->ts;
  493. rel_usecs = ns2usecs(next_ts - iter->ts);
  494. if (verbose) {
  495. char comm[TASK_COMM_LEN];
  496. trace_find_cmdline(entry->pid, comm);
  497. ret = trace_seq_printf(s, "%16s %5d %3d %d %08x %08lx [%08llx]"
  498. " %ld.%03ldms (+%ld.%03ldms): ", comm,
  499. entry->pid, iter->cpu, entry->flags,
  500. entry->preempt_count, iter->idx,
  501. ns2usecs(iter->ts),
  502. abs_usecs / USEC_PER_MSEC,
  503. abs_usecs % USEC_PER_MSEC,
  504. rel_usecs / USEC_PER_MSEC,
  505. rel_usecs % USEC_PER_MSEC);
  506. } else {
  507. ret = lat_print_generic(s, entry, iter->cpu);
  508. if (ret)
  509. ret = lat_print_timestamp(s, abs_usecs, rel_usecs);
  510. }
  511. return ret;
  512. }
  513. static const char state_to_char[] = TASK_STATE_TO_CHAR_STR;
  514. static int task_state_char(unsigned long state)
  515. {
  516. int bit = state ? __ffs(state) + 1 : 0;
  517. return bit < sizeof(state_to_char) - 1 ? state_to_char[bit] : '?';
  518. }
  519. /**
  520. * ftrace_find_event - find a registered event
  521. * @type: the type of event to look for
  522. *
  523. * Returns an event of type @type otherwise NULL
  524. * Called with trace_event_read_lock() held.
  525. */
  526. struct trace_event *ftrace_find_event(int type)
  527. {
  528. struct trace_event *event;
  529. struct hlist_node *n;
  530. unsigned key;
  531. key = type & (EVENT_HASHSIZE - 1);
  532. hlist_for_each_entry(event, n, &event_hash[key], node) {
  533. if (event->type == type)
  534. return event;
  535. }
  536. return NULL;
  537. }
  538. static LIST_HEAD(ftrace_event_list);
  539. static int trace_search_list(struct list_head **list)
  540. {
  541. struct trace_event *e;
  542. int last = __TRACE_LAST_TYPE;
  543. if (list_empty(&ftrace_event_list)) {
  544. *list = &ftrace_event_list;
  545. return last + 1;
  546. }
  547. /*
  548. * We used up all possible max events,
  549. * lets see if somebody freed one.
  550. */
  551. list_for_each_entry(e, &ftrace_event_list, list) {
  552. if (e->type != last + 1)
  553. break;
  554. last++;
  555. }
  556. /* Did we used up all 65 thousand events??? */
  557. if ((last + 1) > FTRACE_MAX_EVENT)
  558. return 0;
  559. *list = &e->list;
  560. return last + 1;
  561. }
  562. void trace_event_read_lock(void)
  563. {
  564. down_read(&trace_event_mutex);
  565. }
  566. void trace_event_read_unlock(void)
  567. {
  568. up_read(&trace_event_mutex);
  569. }
  570. /**
  571. * register_ftrace_event - register output for an event type
  572. * @event: the event type to register
  573. *
  574. * Event types are stored in a hash and this hash is used to
  575. * find a way to print an event. If the @event->type is set
  576. * then it will use that type, otherwise it will assign a
  577. * type to use.
  578. *
  579. * If you assign your own type, please make sure it is added
  580. * to the trace_type enum in trace.h, to avoid collisions
  581. * with the dynamic types.
  582. *
  583. * Returns the event type number or zero on error.
  584. */
  585. int register_ftrace_event(struct trace_event *event)
  586. {
  587. unsigned key;
  588. int ret = 0;
  589. down_write(&trace_event_mutex);
  590. if (WARN_ON(!event))
  591. goto out;
  592. if (WARN_ON(!event->funcs))
  593. goto out;
  594. INIT_LIST_HEAD(&event->list);
  595. if (!event->type) {
  596. struct list_head *list = NULL;
  597. if (next_event_type > FTRACE_MAX_EVENT) {
  598. event->type = trace_search_list(&list);
  599. if (!event->type)
  600. goto out;
  601. } else {
  602. event->type = next_event_type++;
  603. list = &ftrace_event_list;
  604. }
  605. if (WARN_ON(ftrace_find_event(event->type)))
  606. goto out;
  607. list_add_tail(&event->list, list);
  608. } else if (event->type > __TRACE_LAST_TYPE) {
  609. printk(KERN_WARNING "Need to add type to trace.h\n");
  610. WARN_ON(1);
  611. goto out;
  612. } else {
  613. /* Is this event already used */
  614. if (ftrace_find_event(event->type))
  615. goto out;
  616. }
  617. if (event->funcs->trace == NULL)
  618. event->funcs->trace = trace_nop_print;
  619. if (event->funcs->raw == NULL)
  620. event->funcs->raw = trace_nop_print;
  621. if (event->funcs->hex == NULL)
  622. event->funcs->hex = trace_nop_print;
  623. if (event->funcs->binary == NULL)
  624. event->funcs->binary = trace_nop_print;
  625. key = event->type & (EVENT_HASHSIZE - 1);
  626. hlist_add_head(&event->node, &event_hash[key]);
  627. ret = event->type;
  628. out:
  629. up_write(&trace_event_mutex);
  630. return ret;
  631. }
  632. EXPORT_SYMBOL_GPL(register_ftrace_event);
  633. /*
  634. * Used by module code with the trace_event_mutex held for write.
  635. */
  636. int __unregister_ftrace_event(struct trace_event *event)
  637. {
  638. hlist_del(&event->node);
  639. list_del(&event->list);
  640. return 0;
  641. }
  642. /**
  643. * unregister_ftrace_event - remove a no longer used event
  644. * @event: the event to remove
  645. */
  646. int unregister_ftrace_event(struct trace_event *event)
  647. {
  648. down_write(&trace_event_mutex);
  649. __unregister_ftrace_event(event);
  650. up_write(&trace_event_mutex);
  651. return 0;
  652. }
  653. EXPORT_SYMBOL_GPL(unregister_ftrace_event);
  654. /*
  655. * Standard events
  656. */
  657. enum print_line_t trace_nop_print(struct trace_iterator *iter, int flags,
  658. struct trace_event *event)
  659. {
  660. return TRACE_TYPE_HANDLED;
  661. }
  662. /* TRACE_FN */
  663. static enum print_line_t trace_fn_trace(struct trace_iterator *iter, int flags,
  664. struct trace_event *event)
  665. {
  666. struct ftrace_entry *field;
  667. struct trace_seq *s = &iter->seq;
  668. trace_assign_type(field, iter->ent);
  669. if (!seq_print_ip_sym(s, field->ip, flags))
  670. goto partial;
  671. if ((flags & TRACE_ITER_PRINT_PARENT) && field->parent_ip) {
  672. if (!trace_seq_printf(s, " <-"))
  673. goto partial;
  674. if (!seq_print_ip_sym(s,
  675. field->parent_ip,
  676. flags))
  677. goto partial;
  678. }
  679. if (!trace_seq_printf(s, "\n"))
  680. goto partial;
  681. return TRACE_TYPE_HANDLED;
  682. partial:
  683. return TRACE_TYPE_PARTIAL_LINE;
  684. }
  685. static enum print_line_t trace_fn_raw(struct trace_iterator *iter, int flags,
  686. struct trace_event *event)
  687. {
  688. struct ftrace_entry *field;
  689. trace_assign_type(field, iter->ent);
  690. if (!trace_seq_printf(&iter->seq, "%lx %lx\n",
  691. field->ip,
  692. field->parent_ip))
  693. return TRACE_TYPE_PARTIAL_LINE;
  694. return TRACE_TYPE_HANDLED;
  695. }
  696. static enum print_line_t trace_fn_hex(struct trace_iterator *iter, int flags,
  697. struct trace_event *event)
  698. {
  699. struct ftrace_entry *field;
  700. struct trace_seq *s = &iter->seq;
  701. trace_assign_type(field, iter->ent);
  702. SEQ_PUT_HEX_FIELD_RET(s, field->ip);
  703. SEQ_PUT_HEX_FIELD_RET(s, field->parent_ip);
  704. return TRACE_TYPE_HANDLED;
  705. }
  706. static enum print_line_t trace_fn_bin(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. SEQ_PUT_FIELD_RET(s, field->ip);
  713. SEQ_PUT_FIELD_RET(s, field->parent_ip);
  714. return TRACE_TYPE_HANDLED;
  715. }
  716. static struct trace_event_functions trace_fn_funcs = {
  717. .trace = trace_fn_trace,
  718. .raw = trace_fn_raw,
  719. .hex = trace_fn_hex,
  720. .binary = trace_fn_bin,
  721. };
  722. static struct trace_event trace_fn_event = {
  723. .type = TRACE_FN,
  724. .funcs = &trace_fn_funcs,
  725. };
  726. /* TRACE_CTX an TRACE_WAKE */
  727. static enum print_line_t trace_ctxwake_print(struct trace_iterator *iter,
  728. char *delim)
  729. {
  730. struct ctx_switch_entry *field;
  731. char comm[TASK_COMM_LEN];
  732. int S, T;
  733. trace_assign_type(field, iter->ent);
  734. T = task_state_char(field->next_state);
  735. S = task_state_char(field->prev_state);
  736. trace_find_cmdline(field->next_pid, comm);
  737. if (!trace_seq_printf(&iter->seq,
  738. " %5d:%3d:%c %s [%03d] %5d:%3d:%c %s\n",
  739. field->prev_pid,
  740. field->prev_prio,
  741. S, delim,
  742. field->next_cpu,
  743. field->next_pid,
  744. field->next_prio,
  745. T, comm))
  746. return TRACE_TYPE_PARTIAL_LINE;
  747. return TRACE_TYPE_HANDLED;
  748. }
  749. static enum print_line_t trace_ctx_print(struct trace_iterator *iter, int flags,
  750. struct trace_event *event)
  751. {
  752. return trace_ctxwake_print(iter, "==>");
  753. }
  754. static enum print_line_t trace_wake_print(struct trace_iterator *iter,
  755. int flags, struct trace_event *event)
  756. {
  757. return trace_ctxwake_print(iter, " +");
  758. }
  759. static int trace_ctxwake_raw(struct trace_iterator *iter, char S)
  760. {
  761. struct ctx_switch_entry *field;
  762. int T;
  763. trace_assign_type(field, iter->ent);
  764. if (!S)
  765. S = task_state_char(field->prev_state);
  766. T = task_state_char(field->next_state);
  767. if (!trace_seq_printf(&iter->seq, "%d %d %c %d %d %d %c\n",
  768. field->prev_pid,
  769. field->prev_prio,
  770. S,
  771. field->next_cpu,
  772. field->next_pid,
  773. field->next_prio,
  774. T))
  775. return TRACE_TYPE_PARTIAL_LINE;
  776. return TRACE_TYPE_HANDLED;
  777. }
  778. static enum print_line_t trace_ctx_raw(struct trace_iterator *iter, int flags,
  779. struct trace_event *event)
  780. {
  781. return trace_ctxwake_raw(iter, 0);
  782. }
  783. static enum print_line_t trace_wake_raw(struct trace_iterator *iter, int flags,
  784. struct trace_event *event)
  785. {
  786. return trace_ctxwake_raw(iter, '+');
  787. }
  788. static int trace_ctxwake_hex(struct trace_iterator *iter, char S)
  789. {
  790. struct ctx_switch_entry *field;
  791. struct trace_seq *s = &iter->seq;
  792. int T;
  793. trace_assign_type(field, iter->ent);
  794. if (!S)
  795. S = task_state_char(field->prev_state);
  796. T = task_state_char(field->next_state);
  797. SEQ_PUT_HEX_FIELD_RET(s, field->prev_pid);
  798. SEQ_PUT_HEX_FIELD_RET(s, field->prev_prio);
  799. SEQ_PUT_HEX_FIELD_RET(s, S);
  800. SEQ_PUT_HEX_FIELD_RET(s, field->next_cpu);
  801. SEQ_PUT_HEX_FIELD_RET(s, field->next_pid);
  802. SEQ_PUT_HEX_FIELD_RET(s, field->next_prio);
  803. SEQ_PUT_HEX_FIELD_RET(s, T);
  804. return TRACE_TYPE_HANDLED;
  805. }
  806. static enum print_line_t trace_ctx_hex(struct trace_iterator *iter, int flags,
  807. struct trace_event *event)
  808. {
  809. return trace_ctxwake_hex(iter, 0);
  810. }
  811. static enum print_line_t trace_wake_hex(struct trace_iterator *iter, int flags,
  812. struct trace_event *event)
  813. {
  814. return trace_ctxwake_hex(iter, '+');
  815. }
  816. static enum print_line_t trace_ctxwake_bin(struct trace_iterator *iter,
  817. int flags, struct trace_event *event)
  818. {
  819. struct ctx_switch_entry *field;
  820. struct trace_seq *s = &iter->seq;
  821. trace_assign_type(field, iter->ent);
  822. SEQ_PUT_FIELD_RET(s, field->prev_pid);
  823. SEQ_PUT_FIELD_RET(s, field->prev_prio);
  824. SEQ_PUT_FIELD_RET(s, field->prev_state);
  825. SEQ_PUT_FIELD_RET(s, field->next_pid);
  826. SEQ_PUT_FIELD_RET(s, field->next_prio);
  827. SEQ_PUT_FIELD_RET(s, field->next_state);
  828. return TRACE_TYPE_HANDLED;
  829. }
  830. static struct trace_event_functions trace_ctx_funcs = {
  831. .trace = trace_ctx_print,
  832. .raw = trace_ctx_raw,
  833. .hex = trace_ctx_hex,
  834. .binary = trace_ctxwake_bin,
  835. };
  836. static struct trace_event trace_ctx_event = {
  837. .type = TRACE_CTX,
  838. .funcs = &trace_ctx_funcs,
  839. };
  840. static struct trace_event_functions trace_wake_funcs = {
  841. .trace = trace_wake_print,
  842. .raw = trace_wake_raw,
  843. .hex = trace_wake_hex,
  844. .binary = trace_ctxwake_bin,
  845. };
  846. static struct trace_event trace_wake_event = {
  847. .type = TRACE_WAKE,
  848. .funcs = &trace_wake_funcs,
  849. };
  850. /* TRACE_STACK */
  851. static enum print_line_t trace_stack_print(struct trace_iterator *iter,
  852. int flags, struct trace_event *event)
  853. {
  854. struct stack_entry *field;
  855. struct trace_seq *s = &iter->seq;
  856. int i;
  857. trace_assign_type(field, iter->ent);
  858. if (!trace_seq_puts(s, "<stack trace>\n"))
  859. goto partial;
  860. for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
  861. if (!field->caller[i] || (field->caller[i] == ULONG_MAX))
  862. break;
  863. if (!trace_seq_puts(s, " => "))
  864. goto partial;
  865. if (!seq_print_ip_sym(s, field->caller[i], flags))
  866. goto partial;
  867. if (!trace_seq_puts(s, "\n"))
  868. goto partial;
  869. }
  870. return TRACE_TYPE_HANDLED;
  871. partial:
  872. return TRACE_TYPE_PARTIAL_LINE;
  873. }
  874. static struct trace_event_functions trace_stack_funcs = {
  875. .trace = trace_stack_print,
  876. };
  877. static struct trace_event trace_stack_event = {
  878. .type = TRACE_STACK,
  879. .funcs = &trace_stack_funcs,
  880. };
  881. /* TRACE_USER_STACK */
  882. static enum print_line_t trace_user_stack_print(struct trace_iterator *iter,
  883. int flags, struct trace_event *event)
  884. {
  885. struct userstack_entry *field;
  886. struct trace_seq *s = &iter->seq;
  887. trace_assign_type(field, iter->ent);
  888. if (!trace_seq_puts(s, "<user stack trace>\n"))
  889. goto partial;
  890. if (!seq_print_userip_objs(field, s, flags))
  891. goto partial;
  892. return TRACE_TYPE_HANDLED;
  893. partial:
  894. return TRACE_TYPE_PARTIAL_LINE;
  895. }
  896. static struct trace_event_functions trace_user_stack_funcs = {
  897. .trace = trace_user_stack_print,
  898. };
  899. static struct trace_event trace_user_stack_event = {
  900. .type = TRACE_USER_STACK,
  901. .funcs = &trace_user_stack_funcs,
  902. };
  903. /* TRACE_BPRINT */
  904. static enum print_line_t
  905. trace_bprint_print(struct trace_iterator *iter, int flags,
  906. struct trace_event *event)
  907. {
  908. struct trace_entry *entry = iter->ent;
  909. struct trace_seq *s = &iter->seq;
  910. struct bprint_entry *field;
  911. trace_assign_type(field, entry);
  912. if (!seq_print_ip_sym(s, field->ip, flags))
  913. goto partial;
  914. if (!trace_seq_puts(s, ": "))
  915. goto partial;
  916. if (!trace_seq_bprintf(s, field->fmt, field->buf))
  917. goto partial;
  918. return TRACE_TYPE_HANDLED;
  919. partial:
  920. return TRACE_TYPE_PARTIAL_LINE;
  921. }
  922. static enum print_line_t
  923. trace_bprint_raw(struct trace_iterator *iter, int flags,
  924. struct trace_event *event)
  925. {
  926. struct bprint_entry *field;
  927. struct trace_seq *s = &iter->seq;
  928. trace_assign_type(field, iter->ent);
  929. if (!trace_seq_printf(s, ": %lx : ", field->ip))
  930. goto partial;
  931. if (!trace_seq_bprintf(s, field->fmt, field->buf))
  932. goto partial;
  933. return TRACE_TYPE_HANDLED;
  934. partial:
  935. return TRACE_TYPE_PARTIAL_LINE;
  936. }
  937. static struct trace_event_functions trace_bprint_funcs = {
  938. .trace = trace_bprint_print,
  939. .raw = trace_bprint_raw,
  940. };
  941. static struct trace_event trace_bprint_event = {
  942. .type = TRACE_BPRINT,
  943. .funcs = &trace_bprint_funcs,
  944. };
  945. /* TRACE_PRINT */
  946. static enum print_line_t trace_print_print(struct trace_iterator *iter,
  947. int flags, struct trace_event *event)
  948. {
  949. struct print_entry *field;
  950. struct trace_seq *s = &iter->seq;
  951. trace_assign_type(field, iter->ent);
  952. if (!seq_print_ip_sym(s, field->ip, flags))
  953. goto partial;
  954. if (!trace_seq_printf(s, ": %s", field->buf))
  955. goto partial;
  956. return TRACE_TYPE_HANDLED;
  957. partial:
  958. return TRACE_TYPE_PARTIAL_LINE;
  959. }
  960. static enum print_line_t trace_print_raw(struct trace_iterator *iter, int flags,
  961. struct trace_event *event)
  962. {
  963. struct print_entry *field;
  964. trace_assign_type(field, iter->ent);
  965. if (!trace_seq_printf(&iter->seq, "# %lx %s", field->ip, field->buf))
  966. goto partial;
  967. return TRACE_TYPE_HANDLED;
  968. partial:
  969. return TRACE_TYPE_PARTIAL_LINE;
  970. }
  971. static struct trace_event_functions trace_print_funcs = {
  972. .trace = trace_print_print,
  973. .raw = trace_print_raw,
  974. };
  975. static struct trace_event trace_print_event = {
  976. .type = TRACE_PRINT,
  977. .funcs = &trace_print_funcs,
  978. };
  979. static struct trace_event *events[] __initdata = {
  980. &trace_fn_event,
  981. &trace_ctx_event,
  982. &trace_wake_event,
  983. &trace_stack_event,
  984. &trace_user_stack_event,
  985. &trace_bprint_event,
  986. &trace_print_event,
  987. NULL
  988. };
  989. __init static int init_events(void)
  990. {
  991. struct trace_event *event;
  992. int i, ret;
  993. for (i = 0; events[i]; i++) {
  994. event = events[i];
  995. ret = register_ftrace_event(event);
  996. if (!ret) {
  997. printk(KERN_WARNING "event %d failed to register\n",
  998. event->type);
  999. WARN_ON_ONCE(1);
  1000. }
  1001. }
  1002. return 0;
  1003. }
  1004. device_initcall(init_events);