diff options
Diffstat (limited to 'kernel/trace/ftrace.c')
-rw-r--r-- | kernel/trace/ftrace.c | 808 |
1 files changed, 731 insertions, 77 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index f1ed080406c3..3718d55fb4c3 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c | |||
@@ -29,11 +29,13 @@ | |||
29 | #include <linux/list.h> | 29 | #include <linux/list.h> |
30 | #include <linux/hash.h> | 30 | #include <linux/hash.h> |
31 | 31 | ||
32 | #include <trace/sched.h> | 32 | #include <trace/events/sched.h> |
33 | 33 | ||
34 | #include <asm/ftrace.h> | 34 | #include <asm/ftrace.h> |
35 | #include <asm/setup.h> | ||
35 | 36 | ||
36 | #include "trace.h" | 37 | #include "trace_output.h" |
38 | #include "trace_stat.h" | ||
37 | 39 | ||
38 | #define FTRACE_WARN_ON(cond) \ | 40 | #define FTRACE_WARN_ON(cond) \ |
39 | do { \ | 41 | do { \ |
@@ -68,7 +70,7 @@ static DEFINE_MUTEX(ftrace_lock); | |||
68 | 70 | ||
69 | static struct ftrace_ops ftrace_list_end __read_mostly = | 71 | static struct ftrace_ops ftrace_list_end __read_mostly = |
70 | { | 72 | { |
71 | .func = ftrace_stub, | 73 | .func = ftrace_stub, |
72 | }; | 74 | }; |
73 | 75 | ||
74 | static struct ftrace_ops *ftrace_list __read_mostly = &ftrace_list_end; | 76 | static struct ftrace_ops *ftrace_list __read_mostly = &ftrace_list_end; |
@@ -240,6 +242,580 @@ static void ftrace_update_pid_func(void) | |||
240 | #endif | 242 | #endif |
241 | } | 243 | } |
242 | 244 | ||
245 | #ifdef CONFIG_FUNCTION_PROFILER | ||
246 | struct ftrace_profile { | ||
247 | struct hlist_node node; | ||
248 | unsigned long ip; | ||
249 | unsigned long counter; | ||
250 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | ||
251 | unsigned long long time; | ||
252 | #endif | ||
253 | }; | ||
254 | |||
255 | struct ftrace_profile_page { | ||
256 | struct ftrace_profile_page *next; | ||
257 | unsigned long index; | ||
258 | struct ftrace_profile records[]; | ||
259 | }; | ||
260 | |||
261 | struct ftrace_profile_stat { | ||
262 | atomic_t disabled; | ||
263 | struct hlist_head *hash; | ||
264 | struct ftrace_profile_page *pages; | ||
265 | struct ftrace_profile_page *start; | ||
266 | struct tracer_stat stat; | ||
267 | }; | ||
268 | |||
269 | #define PROFILE_RECORDS_SIZE \ | ||
270 | (PAGE_SIZE - offsetof(struct ftrace_profile_page, records)) | ||
271 | |||
272 | #define PROFILES_PER_PAGE \ | ||
273 | (PROFILE_RECORDS_SIZE / sizeof(struct ftrace_profile)) | ||
274 | |||
275 | static int ftrace_profile_bits __read_mostly; | ||
276 | static int ftrace_profile_enabled __read_mostly; | ||
277 | |||
278 | /* ftrace_profile_lock - synchronize the enable and disable of the profiler */ | ||
279 | static DEFINE_MUTEX(ftrace_profile_lock); | ||
280 | |||
281 | static DEFINE_PER_CPU(struct ftrace_profile_stat, ftrace_profile_stats); | ||
282 | |||
283 | #define FTRACE_PROFILE_HASH_SIZE 1024 /* must be power of 2 */ | ||
284 | |||
285 | static void * | ||
286 | function_stat_next(void *v, int idx) | ||
287 | { | ||
288 | struct ftrace_profile *rec = v; | ||
289 | struct ftrace_profile_page *pg; | ||
290 | |||
291 | pg = (struct ftrace_profile_page *)((unsigned long)rec & PAGE_MASK); | ||
292 | |||
293 | again: | ||
294 | rec++; | ||
295 | if ((void *)rec >= (void *)&pg->records[pg->index]) { | ||
296 | pg = pg->next; | ||
297 | if (!pg) | ||
298 | return NULL; | ||
299 | rec = &pg->records[0]; | ||
300 | if (!rec->counter) | ||
301 | goto again; | ||
302 | } | ||
303 | |||
304 | return rec; | ||
305 | } | ||
306 | |||
307 | static void *function_stat_start(struct tracer_stat *trace) | ||
308 | { | ||
309 | struct ftrace_profile_stat *stat = | ||
310 | container_of(trace, struct ftrace_profile_stat, stat); | ||
311 | |||
312 | if (!stat || !stat->start) | ||
313 | return NULL; | ||
314 | |||
315 | return function_stat_next(&stat->start->records[0], 0); | ||
316 | } | ||
317 | |||
318 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | ||
319 | /* function graph compares on total time */ | ||
320 | static int function_stat_cmp(void *p1, void *p2) | ||
321 | { | ||
322 | struct ftrace_profile *a = p1; | ||
323 | struct ftrace_profile *b = p2; | ||
324 | |||
325 | if (a->time < b->time) | ||
326 | return -1; | ||
327 | if (a->time > b->time) | ||
328 | return 1; | ||
329 | else | ||
330 | return 0; | ||
331 | } | ||
332 | #else | ||
333 | /* not function graph compares against hits */ | ||
334 | static int function_stat_cmp(void *p1, void *p2) | ||
335 | { | ||
336 | struct ftrace_profile *a = p1; | ||
337 | struct ftrace_profile *b = p2; | ||
338 | |||
339 | if (a->counter < b->counter) | ||
340 | return -1; | ||
341 | if (a->counter > b->counter) | ||
342 | return 1; | ||
343 | else | ||
344 | return 0; | ||
345 | } | ||
346 | #endif | ||
347 | |||
348 | static int function_stat_headers(struct seq_file *m) | ||
349 | { | ||
350 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | ||
351 | seq_printf(m, " Function " | ||
352 | "Hit Time Avg\n" | ||
353 | " -------- " | ||
354 | "--- ---- ---\n"); | ||
355 | #else | ||
356 | seq_printf(m, " Function Hit\n" | ||
357 | " -------- ---\n"); | ||
358 | #endif | ||
359 | return 0; | ||
360 | } | ||
361 | |||
362 | static int function_stat_show(struct seq_file *m, void *v) | ||
363 | { | ||
364 | struct ftrace_profile *rec = v; | ||
365 | char str[KSYM_SYMBOL_LEN]; | ||
366 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | ||
367 | static DEFINE_MUTEX(mutex); | ||
368 | static struct trace_seq s; | ||
369 | unsigned long long avg; | ||
370 | #endif | ||
371 | |||
372 | kallsyms_lookup(rec->ip, NULL, NULL, NULL, str); | ||
373 | seq_printf(m, " %-30.30s %10lu", str, rec->counter); | ||
374 | |||
375 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | ||
376 | seq_printf(m, " "); | ||
377 | avg = rec->time; | ||
378 | do_div(avg, rec->counter); | ||
379 | |||
380 | mutex_lock(&mutex); | ||
381 | trace_seq_init(&s); | ||
382 | trace_print_graph_duration(rec->time, &s); | ||
383 | trace_seq_puts(&s, " "); | ||
384 | trace_print_graph_duration(avg, &s); | ||
385 | trace_print_seq(m, &s); | ||
386 | mutex_unlock(&mutex); | ||
387 | #endif | ||
388 | seq_putc(m, '\n'); | ||
389 | |||
390 | return 0; | ||
391 | } | ||
392 | |||
393 | static void ftrace_profile_reset(struct ftrace_profile_stat *stat) | ||
394 | { | ||
395 | struct ftrace_profile_page *pg; | ||
396 | |||
397 | pg = stat->pages = stat->start; | ||
398 | |||
399 | while (pg) { | ||
400 | memset(pg->records, 0, PROFILE_RECORDS_SIZE); | ||
401 | pg->index = 0; | ||
402 | pg = pg->next; | ||
403 | } | ||
404 | |||
405 | memset(stat->hash, 0, | ||
406 | FTRACE_PROFILE_HASH_SIZE * sizeof(struct hlist_head)); | ||
407 | } | ||
408 | |||
409 | int ftrace_profile_pages_init(struct ftrace_profile_stat *stat) | ||
410 | { | ||
411 | struct ftrace_profile_page *pg; | ||
412 | int functions; | ||
413 | int pages; | ||
414 | int i; | ||
415 | |||
416 | /* If we already allocated, do nothing */ | ||
417 | if (stat->pages) | ||
418 | return 0; | ||
419 | |||
420 | stat->pages = (void *)get_zeroed_page(GFP_KERNEL); | ||
421 | if (!stat->pages) | ||
422 | return -ENOMEM; | ||
423 | |||
424 | #ifdef CONFIG_DYNAMIC_FTRACE | ||
425 | functions = ftrace_update_tot_cnt; | ||
426 | #else | ||
427 | /* | ||
428 | * We do not know the number of functions that exist because | ||
429 | * dynamic tracing is what counts them. With past experience | ||
430 | * we have around 20K functions. That should be more than enough. | ||
431 | * It is highly unlikely we will execute every function in | ||
432 | * the kernel. | ||
433 | */ | ||
434 | functions = 20000; | ||
435 | #endif | ||
436 | |||
437 | pg = stat->start = stat->pages; | ||
438 | |||
439 | pages = DIV_ROUND_UP(functions, PROFILES_PER_PAGE); | ||
440 | |||
441 | for (i = 0; i < pages; i++) { | ||
442 | pg->next = (void *)get_zeroed_page(GFP_KERNEL); | ||
443 | if (!pg->next) | ||
444 | goto out_free; | ||
445 | pg = pg->next; | ||
446 | } | ||
447 | |||
448 | return 0; | ||
449 | |||
450 | out_free: | ||
451 | pg = stat->start; | ||
452 | while (pg) { | ||
453 | unsigned long tmp = (unsigned long)pg; | ||
454 | |||
455 | pg = pg->next; | ||
456 | free_page(tmp); | ||
457 | } | ||
458 | |||
459 | free_page((unsigned long)stat->pages); | ||
460 | stat->pages = NULL; | ||
461 | stat->start = NULL; | ||
462 | |||
463 | return -ENOMEM; | ||
464 | } | ||
465 | |||
466 | static int ftrace_profile_init_cpu(int cpu) | ||
467 | { | ||
468 | struct ftrace_profile_stat *stat; | ||
469 | int size; | ||
470 | |||
471 | stat = &per_cpu(ftrace_profile_stats, cpu); | ||
472 | |||
473 | if (stat->hash) { | ||
474 | /* If the profile is already created, simply reset it */ | ||
475 | ftrace_profile_reset(stat); | ||
476 | return 0; | ||
477 | } | ||
478 | |||
479 | /* | ||
480 | * We are profiling all functions, but usually only a few thousand | ||
481 | * functions are hit. We'll make a hash of 1024 items. | ||
482 | */ | ||
483 | size = FTRACE_PROFILE_HASH_SIZE; | ||
484 | |||
485 | stat->hash = kzalloc(sizeof(struct hlist_head) * size, GFP_KERNEL); | ||
486 | |||
487 | if (!stat->hash) | ||
488 | return -ENOMEM; | ||
489 | |||
490 | if (!ftrace_profile_bits) { | ||
491 | size--; | ||
492 | |||
493 | for (; size; size >>= 1) | ||
494 | ftrace_profile_bits++; | ||
495 | } | ||
496 | |||
497 | /* Preallocate the function profiling pages */ | ||
498 | if (ftrace_profile_pages_init(stat) < 0) { | ||
499 | kfree(stat->hash); | ||
500 | stat->hash = NULL; | ||
501 | return -ENOMEM; | ||
502 | } | ||
503 | |||
504 | return 0; | ||
505 | } | ||
506 | |||
507 | static int ftrace_profile_init(void) | ||
508 | { | ||
509 | int cpu; | ||
510 | int ret = 0; | ||
511 | |||
512 | for_each_online_cpu(cpu) { | ||
513 | ret = ftrace_profile_init_cpu(cpu); | ||
514 | if (ret) | ||
515 | break; | ||
516 | } | ||
517 | |||
518 | return ret; | ||
519 | } | ||
520 | |||
521 | /* interrupts must be disabled */ | ||
522 | static struct ftrace_profile * | ||
523 | ftrace_find_profiled_func(struct ftrace_profile_stat *stat, unsigned long ip) | ||
524 | { | ||
525 | struct ftrace_profile *rec; | ||
526 | struct hlist_head *hhd; | ||
527 | struct hlist_node *n; | ||
528 | unsigned long key; | ||
529 | |||
530 | key = hash_long(ip, ftrace_profile_bits); | ||
531 | hhd = &stat->hash[key]; | ||
532 | |||
533 | if (hlist_empty(hhd)) | ||
534 | return NULL; | ||
535 | |||
536 | hlist_for_each_entry_rcu(rec, n, hhd, node) { | ||
537 | if (rec->ip == ip) | ||
538 | return rec; | ||
539 | } | ||
540 | |||
541 | return NULL; | ||
542 | } | ||
543 | |||
544 | static void ftrace_add_profile(struct ftrace_profile_stat *stat, | ||
545 | struct ftrace_profile *rec) | ||
546 | { | ||
547 | unsigned long key; | ||
548 | |||
549 | key = hash_long(rec->ip, ftrace_profile_bits); | ||
550 | hlist_add_head_rcu(&rec->node, &stat->hash[key]); | ||
551 | } | ||
552 | |||
553 | /* | ||
554 | * The memory is already allocated, this simply finds a new record to use. | ||
555 | */ | ||
556 | static struct ftrace_profile * | ||
557 | ftrace_profile_alloc(struct ftrace_profile_stat *stat, unsigned long ip) | ||
558 | { | ||
559 | struct ftrace_profile *rec = NULL; | ||
560 | |||
561 | /* prevent recursion (from NMIs) */ | ||
562 | if (atomic_inc_return(&stat->disabled) != 1) | ||
563 | goto out; | ||
564 | |||
565 | /* | ||
566 | * Try to find the function again since an NMI | ||
567 | * could have added it | ||
568 | */ | ||
569 | rec = ftrace_find_profiled_func(stat, ip); | ||
570 | if (rec) | ||
571 | goto out; | ||
572 | |||
573 | if (stat->pages->index == PROFILES_PER_PAGE) { | ||
574 | if (!stat->pages->next) | ||
575 | goto out; | ||
576 | stat->pages = stat->pages->next; | ||
577 | } | ||
578 | |||
579 | rec = &stat->pages->records[stat->pages->index++]; | ||
580 | rec->ip = ip; | ||
581 | ftrace_add_profile(stat, rec); | ||
582 | |||
583 | out: | ||
584 | atomic_dec(&stat->disabled); | ||
585 | |||
586 | return rec; | ||
587 | } | ||
588 | |||
589 | static void | ||
590 | function_profile_call(unsigned long ip, unsigned long parent_ip) | ||
591 | { | ||
592 | struct ftrace_profile_stat *stat; | ||
593 | struct ftrace_profile *rec; | ||
594 | unsigned long flags; | ||
595 | |||
596 | if (!ftrace_profile_enabled) | ||
597 | return; | ||
598 | |||
599 | local_irq_save(flags); | ||
600 | |||
601 | stat = &__get_cpu_var(ftrace_profile_stats); | ||
602 | if (!stat->hash || !ftrace_profile_enabled) | ||
603 | goto out; | ||
604 | |||
605 | rec = ftrace_find_profiled_func(stat, ip); | ||
606 | if (!rec) { | ||
607 | rec = ftrace_profile_alloc(stat, ip); | ||
608 | if (!rec) | ||
609 | goto out; | ||
610 | } | ||
611 | |||
612 | rec->counter++; | ||
613 | out: | ||
614 | local_irq_restore(flags); | ||
615 | } | ||
616 | |||
617 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | ||
618 | static int profile_graph_entry(struct ftrace_graph_ent *trace) | ||
619 | { | ||
620 | function_profile_call(trace->func, 0); | ||
621 | return 1; | ||
622 | } | ||
623 | |||
624 | static void profile_graph_return(struct ftrace_graph_ret *trace) | ||
625 | { | ||
626 | struct ftrace_profile_stat *stat; | ||
627 | unsigned long long calltime; | ||
628 | struct ftrace_profile *rec; | ||
629 | unsigned long flags; | ||
630 | |||
631 | local_irq_save(flags); | ||
632 | stat = &__get_cpu_var(ftrace_profile_stats); | ||
633 | if (!stat->hash || !ftrace_profile_enabled) | ||
634 | goto out; | ||
635 | |||
636 | calltime = trace->rettime - trace->calltime; | ||
637 | |||
638 | if (!(trace_flags & TRACE_ITER_GRAPH_TIME)) { | ||
639 | int index; | ||
640 | |||
641 | index = trace->depth; | ||
642 | |||
643 | /* Append this call time to the parent time to subtract */ | ||
644 | if (index) | ||
645 | current->ret_stack[index - 1].subtime += calltime; | ||
646 | |||
647 | if (current->ret_stack[index].subtime < calltime) | ||
648 | calltime -= current->ret_stack[index].subtime; | ||
649 | else | ||
650 | calltime = 0; | ||
651 | } | ||
652 | |||
653 | rec = ftrace_find_profiled_func(stat, trace->func); | ||
654 | if (rec) | ||
655 | rec->time += calltime; | ||
656 | |||
657 | out: | ||
658 | local_irq_restore(flags); | ||
659 | } | ||
660 | |||
661 | static int register_ftrace_profiler(void) | ||
662 | { | ||
663 | return register_ftrace_graph(&profile_graph_return, | ||
664 | &profile_graph_entry); | ||
665 | } | ||
666 | |||
667 | static void unregister_ftrace_profiler(void) | ||
668 | { | ||
669 | unregister_ftrace_graph(); | ||
670 | } | ||
671 | #else | ||
672 | static struct ftrace_ops ftrace_profile_ops __read_mostly = | ||
673 | { | ||
674 | .func = function_profile_call, | ||
675 | }; | ||
676 | |||
677 | static int register_ftrace_profiler(void) | ||
678 | { | ||
679 | return register_ftrace_function(&ftrace_profile_ops); | ||
680 | } | ||
681 | |||
682 | static void unregister_ftrace_profiler(void) | ||
683 | { | ||
684 | unregister_ftrace_function(&ftrace_profile_ops); | ||
685 | } | ||
686 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | ||
687 | |||
688 | static ssize_t | ||
689 | ftrace_profile_write(struct file *filp, const char __user *ubuf, | ||
690 | size_t cnt, loff_t *ppos) | ||
691 | { | ||
692 | unsigned long val; | ||
693 | char buf[64]; /* big enough to hold a number */ | ||
694 | int ret; | ||
695 | |||
696 | if (cnt >= sizeof(buf)) | ||
697 | return -EINVAL; | ||
698 | |||
699 | if (copy_from_user(&buf, ubuf, cnt)) | ||
700 | return -EFAULT; | ||
701 | |||
702 | buf[cnt] = 0; | ||
703 | |||
704 | ret = strict_strtoul(buf, 10, &val); | ||
705 | if (ret < 0) | ||
706 | return ret; | ||
707 | |||
708 | val = !!val; | ||
709 | |||
710 | mutex_lock(&ftrace_profile_lock); | ||
711 | if (ftrace_profile_enabled ^ val) { | ||
712 | if (val) { | ||
713 | ret = ftrace_profile_init(); | ||
714 | if (ret < 0) { | ||
715 | cnt = ret; | ||
716 | goto out; | ||
717 | } | ||
718 | |||
719 | ret = register_ftrace_profiler(); | ||
720 | if (ret < 0) { | ||
721 | cnt = ret; | ||
722 | goto out; | ||
723 | } | ||
724 | ftrace_profile_enabled = 1; | ||
725 | } else { | ||
726 | ftrace_profile_enabled = 0; | ||
727 | /* | ||
728 | * unregister_ftrace_profiler calls stop_machine | ||
729 | * so this acts like an synchronize_sched. | ||
730 | */ | ||
731 | unregister_ftrace_profiler(); | ||
732 | } | ||
733 | } | ||
734 | out: | ||
735 | mutex_unlock(&ftrace_profile_lock); | ||
736 | |||
737 | filp->f_pos += cnt; | ||
738 | |||
739 | return cnt; | ||
740 | } | ||
741 | |||
742 | static ssize_t | ||
743 | ftrace_profile_read(struct file *filp, char __user *ubuf, | ||
744 | size_t cnt, loff_t *ppos) | ||
745 | { | ||
746 | char buf[64]; /* big enough to hold a number */ | ||
747 | int r; | ||
748 | |||
749 | r = sprintf(buf, "%u\n", ftrace_profile_enabled); | ||
750 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | ||
751 | } | ||
752 | |||
753 | static const struct file_operations ftrace_profile_fops = { | ||
754 | .open = tracing_open_generic, | ||
755 | .read = ftrace_profile_read, | ||
756 | .write = ftrace_profile_write, | ||
757 | }; | ||
758 | |||
759 | /* used to initialize the real stat files */ | ||
760 | static struct tracer_stat function_stats __initdata = { | ||
761 | .name = "functions", | ||
762 | .stat_start = function_stat_start, | ||
763 | .stat_next = function_stat_next, | ||
764 | .stat_cmp = function_stat_cmp, | ||
765 | .stat_headers = function_stat_headers, | ||
766 | .stat_show = function_stat_show | ||
767 | }; | ||
768 | |||
769 | static void ftrace_profile_debugfs(struct dentry *d_tracer) | ||
770 | { | ||
771 | struct ftrace_profile_stat *stat; | ||
772 | struct dentry *entry; | ||
773 | char *name; | ||
774 | int ret; | ||
775 | int cpu; | ||
776 | |||
777 | for_each_possible_cpu(cpu) { | ||
778 | stat = &per_cpu(ftrace_profile_stats, cpu); | ||
779 | |||
780 | /* allocate enough for function name + cpu number */ | ||
781 | name = kmalloc(32, GFP_KERNEL); | ||
782 | if (!name) { | ||
783 | /* | ||
784 | * The files created are permanent, if something happens | ||
785 | * we still do not free memory. | ||
786 | */ | ||
787 | kfree(stat); | ||
788 | WARN(1, | ||
789 | "Could not allocate stat file for cpu %d\n", | ||
790 | cpu); | ||
791 | return; | ||
792 | } | ||
793 | stat->stat = function_stats; | ||
794 | snprintf(name, 32, "function%d", cpu); | ||
795 | stat->stat.name = name; | ||
796 | ret = register_stat_tracer(&stat->stat); | ||
797 | if (ret) { | ||
798 | WARN(1, | ||
799 | "Could not register function stat for cpu %d\n", | ||
800 | cpu); | ||
801 | kfree(name); | ||
802 | return; | ||
803 | } | ||
804 | } | ||
805 | |||
806 | entry = debugfs_create_file("function_profile_enabled", 0644, | ||
807 | d_tracer, NULL, &ftrace_profile_fops); | ||
808 | if (!entry) | ||
809 | pr_warning("Could not create debugfs " | ||
810 | "'function_profile_enabled' entry\n"); | ||
811 | } | ||
812 | |||
813 | #else /* CONFIG_FUNCTION_PROFILER */ | ||
814 | static void ftrace_profile_debugfs(struct dentry *d_tracer) | ||
815 | { | ||
816 | } | ||
817 | #endif /* CONFIG_FUNCTION_PROFILER */ | ||
818 | |||
243 | /* set when tracing only a pid */ | 819 | /* set when tracing only a pid */ |
244 | struct pid *ftrace_pid_trace; | 820 | struct pid *ftrace_pid_trace; |
245 | static struct pid * const ftrace_swapper_pid = &init_struct_pid; | 821 | static struct pid * const ftrace_swapper_pid = &init_struct_pid; |
@@ -261,7 +837,6 @@ struct ftrace_func_probe { | |||
261 | struct rcu_head rcu; | 837 | struct rcu_head rcu; |
262 | }; | 838 | }; |
263 | 839 | ||
264 | |||
265 | enum { | 840 | enum { |
266 | FTRACE_ENABLE_CALLS = (1 << 0), | 841 | FTRACE_ENABLE_CALLS = (1 << 0), |
267 | FTRACE_DISABLE_CALLS = (1 << 1), | 842 | FTRACE_DISABLE_CALLS = (1 << 1), |
@@ -346,30 +921,6 @@ static void ftrace_free_rec(struct dyn_ftrace *rec) | |||
346 | rec->flags |= FTRACE_FL_FREE; | 921 | rec->flags |= FTRACE_FL_FREE; |
347 | } | 922 | } |
348 | 923 | ||
349 | void ftrace_release(void *start, unsigned long size) | ||
350 | { | ||
351 | struct dyn_ftrace *rec; | ||
352 | struct ftrace_page *pg; | ||
353 | unsigned long s = (unsigned long)start; | ||
354 | unsigned long e = s + size; | ||
355 | |||
356 | if (ftrace_disabled || !start) | ||
357 | return; | ||
358 | |||
359 | mutex_lock(&ftrace_lock); | ||
360 | do_for_each_ftrace_rec(pg, rec) { | ||
361 | if ((rec->ip >= s) && (rec->ip < e)) { | ||
362 | /* | ||
363 | * rec->ip is changed in ftrace_free_rec() | ||
364 | * It should not between s and e if record was freed. | ||
365 | */ | ||
366 | FTRACE_WARN_ON(rec->flags & FTRACE_FL_FREE); | ||
367 | ftrace_free_rec(rec); | ||
368 | } | ||
369 | } while_for_each_ftrace_rec(); | ||
370 | mutex_unlock(&ftrace_lock); | ||
371 | } | ||
372 | |||
373 | static struct dyn_ftrace *ftrace_alloc_dyn_node(unsigned long ip) | 924 | static struct dyn_ftrace *ftrace_alloc_dyn_node(unsigned long ip) |
374 | { | 925 | { |
375 | struct dyn_ftrace *rec; | 926 | struct dyn_ftrace *rec; |
@@ -673,6 +1224,13 @@ static void ftrace_shutdown(int command) | |||
673 | return; | 1224 | return; |
674 | 1225 | ||
675 | ftrace_start_up--; | 1226 | ftrace_start_up--; |
1227 | /* | ||
1228 | * Just warn in case of unbalance, no need to kill ftrace, it's not | ||
1229 | * critical but the ftrace_call callers may be never nopped again after | ||
1230 | * further ftrace uses. | ||
1231 | */ | ||
1232 | WARN_ON_ONCE(ftrace_start_up < 0); | ||
1233 | |||
676 | if (!ftrace_start_up) | 1234 | if (!ftrace_start_up) |
677 | command |= FTRACE_DISABLE_CALLS; | 1235 | command |= FTRACE_DISABLE_CALLS; |
678 | 1236 | ||
@@ -1408,7 +1966,7 @@ function_trace_probe_call(unsigned long ip, unsigned long parent_ip) | |||
1408 | 1966 | ||
1409 | static struct ftrace_ops trace_probe_ops __read_mostly = | 1967 | static struct ftrace_ops trace_probe_ops __read_mostly = |
1410 | { | 1968 | { |
1411 | .func = function_trace_probe_call, | 1969 | .func = function_trace_probe_call, |
1412 | }; | 1970 | }; |
1413 | 1971 | ||
1414 | static int ftrace_probe_registered; | 1972 | static int ftrace_probe_registered; |
@@ -1823,6 +2381,45 @@ void ftrace_set_notrace(unsigned char *buf, int len, int reset) | |||
1823 | ftrace_set_regex(buf, len, reset, 0); | 2381 | ftrace_set_regex(buf, len, reset, 0); |
1824 | } | 2382 | } |
1825 | 2383 | ||
2384 | /* | ||
2385 | * command line interface to allow users to set filters on boot up. | ||
2386 | */ | ||
2387 | #define FTRACE_FILTER_SIZE COMMAND_LINE_SIZE | ||
2388 | static char ftrace_notrace_buf[FTRACE_FILTER_SIZE] __initdata; | ||
2389 | static char ftrace_filter_buf[FTRACE_FILTER_SIZE] __initdata; | ||
2390 | |||
2391 | static int __init set_ftrace_notrace(char *str) | ||
2392 | { | ||
2393 | strncpy(ftrace_notrace_buf, str, FTRACE_FILTER_SIZE); | ||
2394 | return 1; | ||
2395 | } | ||
2396 | __setup("ftrace_notrace=", set_ftrace_notrace); | ||
2397 | |||
2398 | static int __init set_ftrace_filter(char *str) | ||
2399 | { | ||
2400 | strncpy(ftrace_filter_buf, str, FTRACE_FILTER_SIZE); | ||
2401 | return 1; | ||
2402 | } | ||
2403 | __setup("ftrace_filter=", set_ftrace_filter); | ||
2404 | |||
2405 | static void __init set_ftrace_early_filter(char *buf, int enable) | ||
2406 | { | ||
2407 | char *func; | ||
2408 | |||
2409 | while (buf) { | ||
2410 | func = strsep(&buf, ","); | ||
2411 | ftrace_set_regex(func, strlen(func), 0, enable); | ||
2412 | } | ||
2413 | } | ||
2414 | |||
2415 | static void __init set_ftrace_early_filters(void) | ||
2416 | { | ||
2417 | if (ftrace_filter_buf[0]) | ||
2418 | set_ftrace_early_filter(ftrace_filter_buf, 1); | ||
2419 | if (ftrace_notrace_buf[0]) | ||
2420 | set_ftrace_early_filter(ftrace_notrace_buf, 0); | ||
2421 | } | ||
2422 | |||
1826 | static int | 2423 | static int |
1827 | ftrace_regex_release(struct inode *inode, struct file *file, int enable) | 2424 | ftrace_regex_release(struct inode *inode, struct file *file, int enable) |
1828 | { | 2425 | { |
@@ -2128,38 +2725,23 @@ static const struct file_operations ftrace_graph_fops = { | |||
2128 | 2725 | ||
2129 | static __init int ftrace_init_dyn_debugfs(struct dentry *d_tracer) | 2726 | static __init int ftrace_init_dyn_debugfs(struct dentry *d_tracer) |
2130 | { | 2727 | { |
2131 | struct dentry *entry; | ||
2132 | 2728 | ||
2133 | entry = debugfs_create_file("available_filter_functions", 0444, | 2729 | trace_create_file("available_filter_functions", 0444, |
2134 | d_tracer, NULL, &ftrace_avail_fops); | 2730 | d_tracer, NULL, &ftrace_avail_fops); |
2135 | if (!entry) | ||
2136 | pr_warning("Could not create debugfs " | ||
2137 | "'available_filter_functions' entry\n"); | ||
2138 | 2731 | ||
2139 | entry = debugfs_create_file("failures", 0444, | 2732 | trace_create_file("failures", 0444, |
2140 | d_tracer, NULL, &ftrace_failures_fops); | 2733 | d_tracer, NULL, &ftrace_failures_fops); |
2141 | if (!entry) | ||
2142 | pr_warning("Could not create debugfs 'failures' entry\n"); | ||
2143 | 2734 | ||
2144 | entry = debugfs_create_file("set_ftrace_filter", 0644, d_tracer, | 2735 | trace_create_file("set_ftrace_filter", 0644, d_tracer, |
2145 | NULL, &ftrace_filter_fops); | 2736 | NULL, &ftrace_filter_fops); |
2146 | if (!entry) | ||
2147 | pr_warning("Could not create debugfs " | ||
2148 | "'set_ftrace_filter' entry\n"); | ||
2149 | 2737 | ||
2150 | entry = debugfs_create_file("set_ftrace_notrace", 0644, d_tracer, | 2738 | trace_create_file("set_ftrace_notrace", 0644, d_tracer, |
2151 | NULL, &ftrace_notrace_fops); | 2739 | NULL, &ftrace_notrace_fops); |
2152 | if (!entry) | ||
2153 | pr_warning("Could not create debugfs " | ||
2154 | "'set_ftrace_notrace' entry\n"); | ||
2155 | 2740 | ||
2156 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | 2741 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
2157 | entry = debugfs_create_file("set_graph_function", 0444, d_tracer, | 2742 | trace_create_file("set_graph_function", 0444, d_tracer, |
2158 | NULL, | 2743 | NULL, |
2159 | &ftrace_graph_fops); | 2744 | &ftrace_graph_fops); |
2160 | if (!entry) | ||
2161 | pr_warning("Could not create debugfs " | ||
2162 | "'set_graph_function' entry\n"); | ||
2163 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | 2745 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
2164 | 2746 | ||
2165 | return 0; | 2747 | return 0; |
@@ -2197,14 +2779,72 @@ static int ftrace_convert_nops(struct module *mod, | |||
2197 | return 0; | 2779 | return 0; |
2198 | } | 2780 | } |
2199 | 2781 | ||
2200 | void ftrace_init_module(struct module *mod, | 2782 | #ifdef CONFIG_MODULES |
2201 | unsigned long *start, unsigned long *end) | 2783 | void ftrace_release(void *start, void *end) |
2784 | { | ||
2785 | struct dyn_ftrace *rec; | ||
2786 | struct ftrace_page *pg; | ||
2787 | unsigned long s = (unsigned long)start; | ||
2788 | unsigned long e = (unsigned long)end; | ||
2789 | |||
2790 | if (ftrace_disabled || !start || start == end) | ||
2791 | return; | ||
2792 | |||
2793 | mutex_lock(&ftrace_lock); | ||
2794 | do_for_each_ftrace_rec(pg, rec) { | ||
2795 | if ((rec->ip >= s) && (rec->ip < e)) { | ||
2796 | /* | ||
2797 | * rec->ip is changed in ftrace_free_rec() | ||
2798 | * It should not between s and e if record was freed. | ||
2799 | */ | ||
2800 | FTRACE_WARN_ON(rec->flags & FTRACE_FL_FREE); | ||
2801 | ftrace_free_rec(rec); | ||
2802 | } | ||
2803 | } while_for_each_ftrace_rec(); | ||
2804 | mutex_unlock(&ftrace_lock); | ||
2805 | } | ||
2806 | |||
2807 | static void ftrace_init_module(struct module *mod, | ||
2808 | unsigned long *start, unsigned long *end) | ||
2202 | { | 2809 | { |
2203 | if (ftrace_disabled || start == end) | 2810 | if (ftrace_disabled || start == end) |
2204 | return; | 2811 | return; |
2205 | ftrace_convert_nops(mod, start, end); | 2812 | ftrace_convert_nops(mod, start, end); |
2206 | } | 2813 | } |
2207 | 2814 | ||
2815 | static int ftrace_module_notify(struct notifier_block *self, | ||
2816 | unsigned long val, void *data) | ||
2817 | { | ||
2818 | struct module *mod = data; | ||
2819 | |||
2820 | switch (val) { | ||
2821 | case MODULE_STATE_COMING: | ||
2822 | ftrace_init_module(mod, mod->ftrace_callsites, | ||
2823 | mod->ftrace_callsites + | ||
2824 | mod->num_ftrace_callsites); | ||
2825 | break; | ||
2826 | case MODULE_STATE_GOING: | ||
2827 | ftrace_release(mod->ftrace_callsites, | ||
2828 | mod->ftrace_callsites + | ||
2829 | mod->num_ftrace_callsites); | ||
2830 | break; | ||
2831 | } | ||
2832 | |||
2833 | return 0; | ||
2834 | } | ||
2835 | #else | ||
2836 | static int ftrace_module_notify(struct notifier_block *self, | ||
2837 | unsigned long val, void *data) | ||
2838 | { | ||
2839 | return 0; | ||
2840 | } | ||
2841 | #endif /* CONFIG_MODULES */ | ||
2842 | |||
2843 | struct notifier_block ftrace_module_nb = { | ||
2844 | .notifier_call = ftrace_module_notify, | ||
2845 | .priority = 0, | ||
2846 | }; | ||
2847 | |||
2208 | extern unsigned long __start_mcount_loc[]; | 2848 | extern unsigned long __start_mcount_loc[]; |
2209 | extern unsigned long __stop_mcount_loc[]; | 2849 | extern unsigned long __stop_mcount_loc[]; |
2210 | 2850 | ||
@@ -2236,6 +2876,12 @@ void __init ftrace_init(void) | |||
2236 | __start_mcount_loc, | 2876 | __start_mcount_loc, |
2237 | __stop_mcount_loc); | 2877 | __stop_mcount_loc); |
2238 | 2878 | ||
2879 | ret = register_module_notifier(&ftrace_module_nb); | ||
2880 | if (ret) | ||
2881 | pr_warning("Failed to register trace ftrace module notifier\n"); | ||
2882 | |||
2883 | set_ftrace_early_filters(); | ||
2884 | |||
2239 | return; | 2885 | return; |
2240 | failed: | 2886 | failed: |
2241 | ftrace_disabled = 1; | 2887 | ftrace_disabled = 1; |
@@ -2417,7 +3063,6 @@ static const struct file_operations ftrace_pid_fops = { | |||
2417 | static __init int ftrace_init_debugfs(void) | 3063 | static __init int ftrace_init_debugfs(void) |
2418 | { | 3064 | { |
2419 | struct dentry *d_tracer; | 3065 | struct dentry *d_tracer; |
2420 | struct dentry *entry; | ||
2421 | 3066 | ||
2422 | d_tracer = tracing_init_dentry(); | 3067 | d_tracer = tracing_init_dentry(); |
2423 | if (!d_tracer) | 3068 | if (!d_tracer) |
@@ -2425,11 +3070,11 @@ static __init int ftrace_init_debugfs(void) | |||
2425 | 3070 | ||
2426 | ftrace_init_dyn_debugfs(d_tracer); | 3071 | ftrace_init_dyn_debugfs(d_tracer); |
2427 | 3072 | ||
2428 | entry = debugfs_create_file("set_ftrace_pid", 0644, d_tracer, | 3073 | trace_create_file("set_ftrace_pid", 0644, d_tracer, |
2429 | NULL, &ftrace_pid_fops); | 3074 | NULL, &ftrace_pid_fops); |
2430 | if (!entry) | 3075 | |
2431 | pr_warning("Could not create debugfs " | 3076 | ftrace_profile_debugfs(d_tracer); |
2432 | "'set_ftrace_pid' entry\n"); | 3077 | |
2433 | return 0; | 3078 | return 0; |
2434 | } | 3079 | } |
2435 | fs_initcall(ftrace_init_debugfs); | 3080 | fs_initcall(ftrace_init_debugfs); |
@@ -2538,7 +3183,7 @@ ftrace_enable_sysctl(struct ctl_table *table, int write, | |||
2538 | 3183 | ||
2539 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | 3184 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
2540 | 3185 | ||
2541 | static atomic_t ftrace_graph_active; | 3186 | static int ftrace_graph_active; |
2542 | static struct notifier_block ftrace_suspend_notifier; | 3187 | static struct notifier_block ftrace_suspend_notifier; |
2543 | 3188 | ||
2544 | int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace) | 3189 | int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace) |
@@ -2580,12 +3225,12 @@ static int alloc_retstack_tasklist(struct ftrace_ret_stack **ret_stack_list) | |||
2580 | } | 3225 | } |
2581 | 3226 | ||
2582 | if (t->ret_stack == NULL) { | 3227 | if (t->ret_stack == NULL) { |
2583 | t->curr_ret_stack = -1; | ||
2584 | /* Make sure IRQs see the -1 first: */ | ||
2585 | barrier(); | ||
2586 | t->ret_stack = ret_stack_list[start++]; | ||
2587 | atomic_set(&t->tracing_graph_pause, 0); | 3228 | atomic_set(&t->tracing_graph_pause, 0); |
2588 | atomic_set(&t->trace_overrun, 0); | 3229 | atomic_set(&t->trace_overrun, 0); |
3230 | t->curr_ret_stack = -1; | ||
3231 | /* Make sure the tasks see the -1 first: */ | ||
3232 | smp_wmb(); | ||
3233 | t->ret_stack = ret_stack_list[start++]; | ||
2589 | } | 3234 | } |
2590 | } while_each_thread(g, t); | 3235 | } while_each_thread(g, t); |
2591 | 3236 | ||
@@ -2643,8 +3288,10 @@ static int start_graph_tracing(void) | |||
2643 | return -ENOMEM; | 3288 | return -ENOMEM; |
2644 | 3289 | ||
2645 | /* The cpu_boot init_task->ret_stack will never be freed */ | 3290 | /* The cpu_boot init_task->ret_stack will never be freed */ |
2646 | for_each_online_cpu(cpu) | 3291 | for_each_online_cpu(cpu) { |
2647 | ftrace_graph_init_task(idle_task(cpu)); | 3292 | if (!idle_task(cpu)->ret_stack) |
3293 | ftrace_graph_init_task(idle_task(cpu)); | ||
3294 | } | ||
2648 | 3295 | ||
2649 | do { | 3296 | do { |
2650 | ret = alloc_retstack_tasklist(ret_stack_list); | 3297 | ret = alloc_retstack_tasklist(ret_stack_list); |
@@ -2690,7 +3337,7 @@ int register_ftrace_graph(trace_func_graph_ret_t retfunc, | |||
2690 | mutex_lock(&ftrace_lock); | 3337 | mutex_lock(&ftrace_lock); |
2691 | 3338 | ||
2692 | /* we currently allow only one tracer registered at a time */ | 3339 | /* we currently allow only one tracer registered at a time */ |
2693 | if (atomic_read(&ftrace_graph_active)) { | 3340 | if (ftrace_graph_active) { |
2694 | ret = -EBUSY; | 3341 | ret = -EBUSY; |
2695 | goto out; | 3342 | goto out; |
2696 | } | 3343 | } |
@@ -2698,10 +3345,10 @@ int register_ftrace_graph(trace_func_graph_ret_t retfunc, | |||
2698 | ftrace_suspend_notifier.notifier_call = ftrace_suspend_notifier_call; | 3345 | ftrace_suspend_notifier.notifier_call = ftrace_suspend_notifier_call; |
2699 | register_pm_notifier(&ftrace_suspend_notifier); | 3346 | register_pm_notifier(&ftrace_suspend_notifier); |
2700 | 3347 | ||
2701 | atomic_inc(&ftrace_graph_active); | 3348 | ftrace_graph_active++; |
2702 | ret = start_graph_tracing(); | 3349 | ret = start_graph_tracing(); |
2703 | if (ret) { | 3350 | if (ret) { |
2704 | atomic_dec(&ftrace_graph_active); | 3351 | ftrace_graph_active--; |
2705 | goto out; | 3352 | goto out; |
2706 | } | 3353 | } |
2707 | 3354 | ||
@@ -2719,10 +3366,10 @@ void unregister_ftrace_graph(void) | |||
2719 | { | 3366 | { |
2720 | mutex_lock(&ftrace_lock); | 3367 | mutex_lock(&ftrace_lock); |
2721 | 3368 | ||
2722 | if (!unlikely(atomic_read(&ftrace_graph_active))) | 3369 | if (unlikely(!ftrace_graph_active)) |
2723 | goto out; | 3370 | goto out; |
2724 | 3371 | ||
2725 | atomic_dec(&ftrace_graph_active); | 3372 | ftrace_graph_active--; |
2726 | unregister_trace_sched_switch(ftrace_graph_probe_sched_switch); | 3373 | unregister_trace_sched_switch(ftrace_graph_probe_sched_switch); |
2727 | ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub; | 3374 | ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub; |
2728 | ftrace_graph_entry = ftrace_graph_entry_stub; | 3375 | ftrace_graph_entry = ftrace_graph_entry_stub; |
@@ -2736,18 +3383,25 @@ void unregister_ftrace_graph(void) | |||
2736 | /* Allocate a return stack for newly created task */ | 3383 | /* Allocate a return stack for newly created task */ |
2737 | void ftrace_graph_init_task(struct task_struct *t) | 3384 | void ftrace_graph_init_task(struct task_struct *t) |
2738 | { | 3385 | { |
2739 | if (atomic_read(&ftrace_graph_active)) { | 3386 | /* Make sure we do not use the parent ret_stack */ |
2740 | t->ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH | 3387 | t->ret_stack = NULL; |
3388 | |||
3389 | if (ftrace_graph_active) { | ||
3390 | struct ftrace_ret_stack *ret_stack; | ||
3391 | |||
3392 | ret_stack = kmalloc(FTRACE_RETFUNC_DEPTH | ||
2741 | * sizeof(struct ftrace_ret_stack), | 3393 | * sizeof(struct ftrace_ret_stack), |
2742 | GFP_KERNEL); | 3394 | GFP_KERNEL); |
2743 | if (!t->ret_stack) | 3395 | if (!ret_stack) |
2744 | return; | 3396 | return; |
2745 | t->curr_ret_stack = -1; | 3397 | t->curr_ret_stack = -1; |
2746 | atomic_set(&t->tracing_graph_pause, 0); | 3398 | atomic_set(&t->tracing_graph_pause, 0); |
2747 | atomic_set(&t->trace_overrun, 0); | 3399 | atomic_set(&t->trace_overrun, 0); |
2748 | t->ftrace_timestamp = 0; | 3400 | t->ftrace_timestamp = 0; |
2749 | } else | 3401 | /* make curr_ret_stack visable before we add the ret_stack */ |
2750 | t->ret_stack = NULL; | 3402 | smp_wmb(); |
3403 | t->ret_stack = ret_stack; | ||
3404 | } | ||
2751 | } | 3405 | } |
2752 | 3406 | ||
2753 | void ftrace_graph_exit_task(struct task_struct *t) | 3407 | void ftrace_graph_exit_task(struct task_struct *t) |