xref: /openbmc/linux/tools/perf/builtin-lock.c (revision f9900dd0)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <errno.h>
3 #include <inttypes.h>
4 #include "builtin.h"
5 #include "perf.h"
6 
7 #include "util/evlist.h" // for struct evsel_str_handler
8 #include "util/evsel.h"
9 #include "util/symbol.h"
10 #include "util/thread.h"
11 #include "util/header.h"
12 
13 #include <subcmd/pager.h>
14 #include <subcmd/parse-options.h>
15 #include "util/trace-event.h"
16 
17 #include "util/debug.h"
18 #include "util/session.h"
19 #include "util/tool.h"
20 #include "util/data.h"
21 
22 #include <sys/types.h>
23 #include <sys/prctl.h>
24 #include <semaphore.h>
25 #include <pthread.h>
26 #include <math.h>
27 #include <limits.h>
28 
29 #include <linux/list.h>
30 #include <linux/hash.h>
31 #include <linux/kernel.h>
32 #include <linux/zalloc.h>
33 #include <linux/err.h>
34 
35 static struct perf_session *session;
36 
37 /* based on kernel/lockdep.c */
38 #define LOCKHASH_BITS		12
39 #define LOCKHASH_SIZE		(1UL << LOCKHASH_BITS)
40 
41 static struct hlist_head lockhash_table[LOCKHASH_SIZE];
42 
43 #define __lockhashfn(key)	hash_long((unsigned long)key, LOCKHASH_BITS)
44 #define lockhashentry(key)	(lockhash_table + __lockhashfn((key)))
45 
46 struct lock_stat {
47 	struct hlist_node	hash_entry;
48 	struct rb_node		rb;		/* used for sorting */
49 
50 	u64			addr;		/* address of lockdep_map, used as ID */
51 	char			*name;		/* for strcpy(), we cannot use const */
52 
53 	unsigned int		nr_acquire;
54 	unsigned int		nr_acquired;
55 	unsigned int		nr_contended;
56 	unsigned int		nr_release;
57 
58 	unsigned int		nr_readlock;
59 	unsigned int		nr_trylock;
60 
61 	/* these times are in nano sec. */
62 	u64                     avg_wait_time;
63 	u64			wait_time_total;
64 	u64			wait_time_min;
65 	u64			wait_time_max;
66 
67 	int			discard; /* flag of blacklist */
68 	int			combined;
69 };
70 
71 /*
72  * States of lock_seq_stat
73  *
74  * UNINITIALIZED is required for detecting first event of acquire.
75  * As the nature of lock events, there is no guarantee
76  * that the first event for the locks are acquire,
77  * it can be acquired, contended or release.
78  */
79 #define SEQ_STATE_UNINITIALIZED      0	       /* initial state */
80 #define SEQ_STATE_RELEASED	1
81 #define SEQ_STATE_ACQUIRING	2
82 #define SEQ_STATE_ACQUIRED	3
83 #define SEQ_STATE_READ_ACQUIRED	4
84 #define SEQ_STATE_CONTENDED	5
85 
86 /*
87  * MAX_LOCK_DEPTH
88  * Imported from include/linux/sched.h.
89  * Should this be synchronized?
90  */
91 #define MAX_LOCK_DEPTH 48
92 
93 /*
94  * struct lock_seq_stat:
95  * Place to put on state of one lock sequence
96  * 1) acquire -> acquired -> release
97  * 2) acquire -> contended -> acquired -> release
98  * 3) acquire (with read or try) -> release
99  * 4) Are there other patterns?
100  */
101 struct lock_seq_stat {
102 	struct list_head        list;
103 	int			state;
104 	u64			prev_event_time;
105 	u64                     addr;
106 
107 	int                     read_count;
108 };
109 
110 struct thread_stat {
111 	struct rb_node		rb;
112 
113 	u32                     tid;
114 	struct list_head        seq_list;
115 };
116 
117 static struct rb_root		thread_stats;
118 
119 static bool combine_locks;
120 
121 static struct thread_stat *thread_stat_find(u32 tid)
122 {
123 	struct rb_node *node;
124 	struct thread_stat *st;
125 
126 	node = thread_stats.rb_node;
127 	while (node) {
128 		st = container_of(node, struct thread_stat, rb);
129 		if (st->tid == tid)
130 			return st;
131 		else if (tid < st->tid)
132 			node = node->rb_left;
133 		else
134 			node = node->rb_right;
135 	}
136 
137 	return NULL;
138 }
139 
140 static void thread_stat_insert(struct thread_stat *new)
141 {
142 	struct rb_node **rb = &thread_stats.rb_node;
143 	struct rb_node *parent = NULL;
144 	struct thread_stat *p;
145 
146 	while (*rb) {
147 		p = container_of(*rb, struct thread_stat, rb);
148 		parent = *rb;
149 
150 		if (new->tid < p->tid)
151 			rb = &(*rb)->rb_left;
152 		else if (new->tid > p->tid)
153 			rb = &(*rb)->rb_right;
154 		else
155 			BUG_ON("inserting invalid thread_stat\n");
156 	}
157 
158 	rb_link_node(&new->rb, parent, rb);
159 	rb_insert_color(&new->rb, &thread_stats);
160 }
161 
162 static struct thread_stat *thread_stat_findnew_after_first(u32 tid)
163 {
164 	struct thread_stat *st;
165 
166 	st = thread_stat_find(tid);
167 	if (st)
168 		return st;
169 
170 	st = zalloc(sizeof(struct thread_stat));
171 	if (!st) {
172 		pr_err("memory allocation failed\n");
173 		return NULL;
174 	}
175 
176 	st->tid = tid;
177 	INIT_LIST_HEAD(&st->seq_list);
178 
179 	thread_stat_insert(st);
180 
181 	return st;
182 }
183 
184 static struct thread_stat *thread_stat_findnew_first(u32 tid);
185 static struct thread_stat *(*thread_stat_findnew)(u32 tid) =
186 	thread_stat_findnew_first;
187 
188 static struct thread_stat *thread_stat_findnew_first(u32 tid)
189 {
190 	struct thread_stat *st;
191 
192 	st = zalloc(sizeof(struct thread_stat));
193 	if (!st) {
194 		pr_err("memory allocation failed\n");
195 		return NULL;
196 	}
197 	st->tid = tid;
198 	INIT_LIST_HEAD(&st->seq_list);
199 
200 	rb_link_node(&st->rb, NULL, &thread_stats.rb_node);
201 	rb_insert_color(&st->rb, &thread_stats);
202 
203 	thread_stat_findnew = thread_stat_findnew_after_first;
204 	return st;
205 }
206 
207 /* build simple key function one is bigger than two */
208 #define SINGLE_KEY(member)						\
209 	static int lock_stat_key_ ## member(struct lock_stat *one,	\
210 					 struct lock_stat *two)		\
211 	{								\
212 		return one->member > two->member;			\
213 	}
214 
215 SINGLE_KEY(nr_acquired)
216 SINGLE_KEY(nr_contended)
217 SINGLE_KEY(avg_wait_time)
218 SINGLE_KEY(wait_time_total)
219 SINGLE_KEY(wait_time_max)
220 
221 static int lock_stat_key_wait_time_min(struct lock_stat *one,
222 					struct lock_stat *two)
223 {
224 	u64 s1 = one->wait_time_min;
225 	u64 s2 = two->wait_time_min;
226 	if (s1 == ULLONG_MAX)
227 		s1 = 0;
228 	if (s2 == ULLONG_MAX)
229 		s2 = 0;
230 	return s1 > s2;
231 }
232 
233 struct lock_key {
234 	/*
235 	 * name: the value for specify by user
236 	 * this should be simpler than raw name of member
237 	 * e.g. nr_acquired -> acquired, wait_time_total -> wait_total
238 	 */
239 	const char		*name;
240 	int			(*key)(struct lock_stat*, struct lock_stat*);
241 };
242 
243 static const char		*sort_key = "acquired";
244 
245 static int			(*compare)(struct lock_stat *, struct lock_stat *);
246 
247 static struct rb_root		sorted; /* place to store intermediate data */
248 static struct rb_root		result;	/* place to store sorted data */
249 
250 #define DEF_KEY_LOCK(name, fn_suffix)	\
251 	{ #name, lock_stat_key_ ## fn_suffix }
252 struct lock_key keys[] = {
253 	DEF_KEY_LOCK(acquired, nr_acquired),
254 	DEF_KEY_LOCK(contended, nr_contended),
255 	DEF_KEY_LOCK(avg_wait, avg_wait_time),
256 	DEF_KEY_LOCK(wait_total, wait_time_total),
257 	DEF_KEY_LOCK(wait_min, wait_time_min),
258 	DEF_KEY_LOCK(wait_max, wait_time_max),
259 
260 	/* extra comparisons much complicated should be here */
261 
262 	{ NULL, NULL }
263 };
264 
265 static int select_key(void)
266 {
267 	int i;
268 
269 	for (i = 0; keys[i].name; i++) {
270 		if (!strcmp(keys[i].name, sort_key)) {
271 			compare = keys[i].key;
272 			return 0;
273 		}
274 	}
275 
276 	pr_err("Unknown compare key: %s\n", sort_key);
277 
278 	return -1;
279 }
280 
281 static void combine_lock_stats(struct lock_stat *st)
282 {
283 	struct rb_node **rb = &sorted.rb_node;
284 	struct rb_node *parent = NULL;
285 	struct lock_stat *p;
286 	int ret;
287 
288 	while (*rb) {
289 		p = container_of(*rb, struct lock_stat, rb);
290 		parent = *rb;
291 
292 		if (st->name && p->name)
293 			ret = strcmp(st->name, p->name);
294 		else
295 			ret = !!st->name - !!p->name;
296 
297 		if (ret == 0) {
298 			if (st->discard)
299 				goto out;
300 
301 			p->nr_acquired += st->nr_acquired;
302 			p->nr_contended += st->nr_contended;
303 			p->wait_time_total += st->wait_time_total;
304 
305 			if (p->nr_contended)
306 				p->avg_wait_time = p->wait_time_total / p->nr_contended;
307 
308 			if (p->wait_time_min > st->wait_time_min)
309 				p->wait_time_min = st->wait_time_min;
310 			if (p->wait_time_max < st->wait_time_max)
311 				p->wait_time_max = st->wait_time_max;
312 
313 			/* now it got a new !discard record */
314 			p->discard = 0;
315 
316 out:
317 			st->combined = 1;
318 			return;
319 		}
320 
321 		if (ret < 0)
322 			rb = &(*rb)->rb_left;
323 		else
324 			rb = &(*rb)->rb_right;
325 	}
326 
327 	rb_link_node(&st->rb, parent, rb);
328 	rb_insert_color(&st->rb, &sorted);
329 
330 	if (st->discard) {
331 		st->nr_acquired = 0;
332 		st->nr_contended = 0;
333 		st->wait_time_total = 0;
334 		st->avg_wait_time = 0;
335 		st->wait_time_min = ULLONG_MAX;
336 		st->wait_time_max = 0;
337 	}
338 }
339 
340 static void insert_to_result(struct lock_stat *st,
341 			     int (*bigger)(struct lock_stat *, struct lock_stat *))
342 {
343 	struct rb_node **rb = &result.rb_node;
344 	struct rb_node *parent = NULL;
345 	struct lock_stat *p;
346 
347 	if (combine_locks && st->combined)
348 		return;
349 
350 	while (*rb) {
351 		p = container_of(*rb, struct lock_stat, rb);
352 		parent = *rb;
353 
354 		if (bigger(st, p))
355 			rb = &(*rb)->rb_left;
356 		else
357 			rb = &(*rb)->rb_right;
358 	}
359 
360 	rb_link_node(&st->rb, parent, rb);
361 	rb_insert_color(&st->rb, &result);
362 }
363 
364 /* returns left most element of result, and erase it */
365 static struct lock_stat *pop_from_result(void)
366 {
367 	struct rb_node *node = result.rb_node;
368 
369 	if (!node)
370 		return NULL;
371 
372 	while (node->rb_left)
373 		node = node->rb_left;
374 
375 	rb_erase(node, &result);
376 	return container_of(node, struct lock_stat, rb);
377 }
378 
379 static struct lock_stat *lock_stat_findnew(u64 addr, const char *name)
380 {
381 	struct hlist_head *entry = lockhashentry(addr);
382 	struct lock_stat *ret, *new;
383 
384 	hlist_for_each_entry(ret, entry, hash_entry) {
385 		if (ret->addr == addr)
386 			return ret;
387 	}
388 
389 	new = zalloc(sizeof(struct lock_stat));
390 	if (!new)
391 		goto alloc_failed;
392 
393 	new->addr = addr;
394 	new->name = zalloc(sizeof(char) * strlen(name) + 1);
395 	if (!new->name) {
396 		free(new);
397 		goto alloc_failed;
398 	}
399 
400 	strcpy(new->name, name);
401 	new->wait_time_min = ULLONG_MAX;
402 
403 	hlist_add_head(&new->hash_entry, entry);
404 	return new;
405 
406 alloc_failed:
407 	pr_err("memory allocation failed\n");
408 	return NULL;
409 }
410 
411 struct trace_lock_handler {
412 	int (*acquire_event)(struct evsel *evsel,
413 			     struct perf_sample *sample);
414 
415 	int (*acquired_event)(struct evsel *evsel,
416 			      struct perf_sample *sample);
417 
418 	int (*contended_event)(struct evsel *evsel,
419 			       struct perf_sample *sample);
420 
421 	int (*release_event)(struct evsel *evsel,
422 			     struct perf_sample *sample);
423 };
424 
425 static struct lock_seq_stat *get_seq(struct thread_stat *ts, u64 addr)
426 {
427 	struct lock_seq_stat *seq;
428 
429 	list_for_each_entry(seq, &ts->seq_list, list) {
430 		if (seq->addr == addr)
431 			return seq;
432 	}
433 
434 	seq = zalloc(sizeof(struct lock_seq_stat));
435 	if (!seq) {
436 		pr_err("memory allocation failed\n");
437 		return NULL;
438 	}
439 	seq->state = SEQ_STATE_UNINITIALIZED;
440 	seq->addr = addr;
441 
442 	list_add(&seq->list, &ts->seq_list);
443 	return seq;
444 }
445 
446 enum broken_state {
447 	BROKEN_ACQUIRE,
448 	BROKEN_ACQUIRED,
449 	BROKEN_CONTENDED,
450 	BROKEN_RELEASE,
451 	BROKEN_MAX,
452 };
453 
454 static int bad_hist[BROKEN_MAX];
455 
456 enum acquire_flags {
457 	TRY_LOCK = 1,
458 	READ_LOCK = 2,
459 };
460 
461 static int report_lock_acquire_event(struct evsel *evsel,
462 				     struct perf_sample *sample)
463 {
464 	struct lock_stat *ls;
465 	struct thread_stat *ts;
466 	struct lock_seq_stat *seq;
467 	const char *name = evsel__strval(evsel, sample, "name");
468 	u64 addr = evsel__intval(evsel, sample, "lockdep_addr");
469 	int flag = evsel__intval(evsel, sample, "flags");
470 
471 	ls = lock_stat_findnew(addr, name);
472 	if (!ls)
473 		return -ENOMEM;
474 	if (ls->discard)
475 		return 0;
476 
477 	ts = thread_stat_findnew(sample->tid);
478 	if (!ts)
479 		return -ENOMEM;
480 
481 	seq = get_seq(ts, addr);
482 	if (!seq)
483 		return -ENOMEM;
484 
485 	switch (seq->state) {
486 	case SEQ_STATE_UNINITIALIZED:
487 	case SEQ_STATE_RELEASED:
488 		if (!flag) {
489 			seq->state = SEQ_STATE_ACQUIRING;
490 		} else {
491 			if (flag & TRY_LOCK)
492 				ls->nr_trylock++;
493 			if (flag & READ_LOCK)
494 				ls->nr_readlock++;
495 			seq->state = SEQ_STATE_READ_ACQUIRED;
496 			seq->read_count = 1;
497 			ls->nr_acquired++;
498 		}
499 		break;
500 	case SEQ_STATE_READ_ACQUIRED:
501 		if (flag & READ_LOCK) {
502 			seq->read_count++;
503 			ls->nr_acquired++;
504 			goto end;
505 		} else {
506 			goto broken;
507 		}
508 		break;
509 	case SEQ_STATE_ACQUIRED:
510 	case SEQ_STATE_ACQUIRING:
511 	case SEQ_STATE_CONTENDED:
512 broken:
513 		/* broken lock sequence, discard it */
514 		ls->discard = 1;
515 		bad_hist[BROKEN_ACQUIRE]++;
516 		list_del_init(&seq->list);
517 		free(seq);
518 		goto end;
519 	default:
520 		BUG_ON("Unknown state of lock sequence found!\n");
521 		break;
522 	}
523 
524 	ls->nr_acquire++;
525 	seq->prev_event_time = sample->time;
526 end:
527 	return 0;
528 }
529 
530 static int report_lock_acquired_event(struct evsel *evsel,
531 				      struct perf_sample *sample)
532 {
533 	struct lock_stat *ls;
534 	struct thread_stat *ts;
535 	struct lock_seq_stat *seq;
536 	u64 contended_term;
537 	const char *name = evsel__strval(evsel, sample, "name");
538 	u64 addr = evsel__intval(evsel, sample, "lockdep_addr");
539 
540 	ls = lock_stat_findnew(addr, name);
541 	if (!ls)
542 		return -ENOMEM;
543 	if (ls->discard)
544 		return 0;
545 
546 	ts = thread_stat_findnew(sample->tid);
547 	if (!ts)
548 		return -ENOMEM;
549 
550 	seq = get_seq(ts, addr);
551 	if (!seq)
552 		return -ENOMEM;
553 
554 	switch (seq->state) {
555 	case SEQ_STATE_UNINITIALIZED:
556 		/* orphan event, do nothing */
557 		return 0;
558 	case SEQ_STATE_ACQUIRING:
559 		break;
560 	case SEQ_STATE_CONTENDED:
561 		contended_term = sample->time - seq->prev_event_time;
562 		ls->wait_time_total += contended_term;
563 		if (contended_term < ls->wait_time_min)
564 			ls->wait_time_min = contended_term;
565 		if (ls->wait_time_max < contended_term)
566 			ls->wait_time_max = contended_term;
567 		break;
568 	case SEQ_STATE_RELEASED:
569 	case SEQ_STATE_ACQUIRED:
570 	case SEQ_STATE_READ_ACQUIRED:
571 		/* broken lock sequence, discard it */
572 		ls->discard = 1;
573 		bad_hist[BROKEN_ACQUIRED]++;
574 		list_del_init(&seq->list);
575 		free(seq);
576 		goto end;
577 	default:
578 		BUG_ON("Unknown state of lock sequence found!\n");
579 		break;
580 	}
581 
582 	seq->state = SEQ_STATE_ACQUIRED;
583 	ls->nr_acquired++;
584 	ls->avg_wait_time = ls->nr_contended ? ls->wait_time_total/ls->nr_contended : 0;
585 	seq->prev_event_time = sample->time;
586 end:
587 	return 0;
588 }
589 
590 static int report_lock_contended_event(struct evsel *evsel,
591 				       struct perf_sample *sample)
592 {
593 	struct lock_stat *ls;
594 	struct thread_stat *ts;
595 	struct lock_seq_stat *seq;
596 	const char *name = evsel__strval(evsel, sample, "name");
597 	u64 addr = evsel__intval(evsel, sample, "lockdep_addr");
598 
599 	ls = lock_stat_findnew(addr, name);
600 	if (!ls)
601 		return -ENOMEM;
602 	if (ls->discard)
603 		return 0;
604 
605 	ts = thread_stat_findnew(sample->tid);
606 	if (!ts)
607 		return -ENOMEM;
608 
609 	seq = get_seq(ts, addr);
610 	if (!seq)
611 		return -ENOMEM;
612 
613 	switch (seq->state) {
614 	case SEQ_STATE_UNINITIALIZED:
615 		/* orphan event, do nothing */
616 		return 0;
617 	case SEQ_STATE_ACQUIRING:
618 		break;
619 	case SEQ_STATE_RELEASED:
620 	case SEQ_STATE_ACQUIRED:
621 	case SEQ_STATE_READ_ACQUIRED:
622 	case SEQ_STATE_CONTENDED:
623 		/* broken lock sequence, discard it */
624 		ls->discard = 1;
625 		bad_hist[BROKEN_CONTENDED]++;
626 		list_del_init(&seq->list);
627 		free(seq);
628 		goto end;
629 	default:
630 		BUG_ON("Unknown state of lock sequence found!\n");
631 		break;
632 	}
633 
634 	seq->state = SEQ_STATE_CONTENDED;
635 	ls->nr_contended++;
636 	ls->avg_wait_time = ls->wait_time_total/ls->nr_contended;
637 	seq->prev_event_time = sample->time;
638 end:
639 	return 0;
640 }
641 
642 static int report_lock_release_event(struct evsel *evsel,
643 				     struct perf_sample *sample)
644 {
645 	struct lock_stat *ls;
646 	struct thread_stat *ts;
647 	struct lock_seq_stat *seq;
648 	const char *name = evsel__strval(evsel, sample, "name");
649 	u64 addr = evsel__intval(evsel, sample, "lockdep_addr");
650 
651 	ls = lock_stat_findnew(addr, name);
652 	if (!ls)
653 		return -ENOMEM;
654 	if (ls->discard)
655 		return 0;
656 
657 	ts = thread_stat_findnew(sample->tid);
658 	if (!ts)
659 		return -ENOMEM;
660 
661 	seq = get_seq(ts, addr);
662 	if (!seq)
663 		return -ENOMEM;
664 
665 	switch (seq->state) {
666 	case SEQ_STATE_UNINITIALIZED:
667 		goto end;
668 	case SEQ_STATE_ACQUIRED:
669 		break;
670 	case SEQ_STATE_READ_ACQUIRED:
671 		seq->read_count--;
672 		BUG_ON(seq->read_count < 0);
673 		if (seq->read_count) {
674 			ls->nr_release++;
675 			goto end;
676 		}
677 		break;
678 	case SEQ_STATE_ACQUIRING:
679 	case SEQ_STATE_CONTENDED:
680 	case SEQ_STATE_RELEASED:
681 		/* broken lock sequence, discard it */
682 		ls->discard = 1;
683 		bad_hist[BROKEN_RELEASE]++;
684 		goto free_seq;
685 	default:
686 		BUG_ON("Unknown state of lock sequence found!\n");
687 		break;
688 	}
689 
690 	ls->nr_release++;
691 free_seq:
692 	list_del_init(&seq->list);
693 	free(seq);
694 end:
695 	return 0;
696 }
697 
698 /* lock oriented handlers */
699 /* TODO: handlers for CPU oriented, thread oriented */
700 static struct trace_lock_handler report_lock_ops  = {
701 	.acquire_event		= report_lock_acquire_event,
702 	.acquired_event		= report_lock_acquired_event,
703 	.contended_event	= report_lock_contended_event,
704 	.release_event		= report_lock_release_event,
705 };
706 
707 static struct trace_lock_handler *trace_handler;
708 
709 static int evsel__process_lock_acquire(struct evsel *evsel, struct perf_sample *sample)
710 {
711 	if (trace_handler->acquire_event)
712 		return trace_handler->acquire_event(evsel, sample);
713 	return 0;
714 }
715 
716 static int evsel__process_lock_acquired(struct evsel *evsel, struct perf_sample *sample)
717 {
718 	if (trace_handler->acquired_event)
719 		return trace_handler->acquired_event(evsel, sample);
720 	return 0;
721 }
722 
723 static int evsel__process_lock_contended(struct evsel *evsel, struct perf_sample *sample)
724 {
725 	if (trace_handler->contended_event)
726 		return trace_handler->contended_event(evsel, sample);
727 	return 0;
728 }
729 
730 static int evsel__process_lock_release(struct evsel *evsel, struct perf_sample *sample)
731 {
732 	if (trace_handler->release_event)
733 		return trace_handler->release_event(evsel, sample);
734 	return 0;
735 }
736 
737 static void print_bad_events(int bad, int total)
738 {
739 	/* Output for debug, this have to be removed */
740 	int i;
741 	const char *name[4] =
742 		{ "acquire", "acquired", "contended", "release" };
743 
744 	pr_info("\n=== output for debug===\n\n");
745 	pr_info("bad: %d, total: %d\n", bad, total);
746 	pr_info("bad rate: %.2f %%\n", (double)bad / (double)total * 100);
747 	pr_info("histogram of events caused bad sequence\n");
748 	for (i = 0; i < BROKEN_MAX; i++)
749 		pr_info(" %10s: %d\n", name[i], bad_hist[i]);
750 }
751 
752 /* TODO: various way to print, coloring, nano or milli sec */
753 static void print_result(void)
754 {
755 	struct lock_stat *st;
756 	char cut_name[20];
757 	int bad, total;
758 
759 	pr_info("%20s ", "Name");
760 	pr_info("%10s ", "acquired");
761 	pr_info("%10s ", "contended");
762 
763 	pr_info("%15s ", "avg wait (ns)");
764 	pr_info("%15s ", "total wait (ns)");
765 	pr_info("%15s ", "max wait (ns)");
766 	pr_info("%15s ", "min wait (ns)");
767 
768 	pr_info("\n\n");
769 
770 	bad = total = 0;
771 	while ((st = pop_from_result())) {
772 		total++;
773 		if (st->discard) {
774 			bad++;
775 			continue;
776 		}
777 		bzero(cut_name, 20);
778 
779 		if (strlen(st->name) < 20) {
780 			/* output raw name */
781 			pr_info("%20s ", st->name);
782 		} else {
783 			strncpy(cut_name, st->name, 16);
784 			cut_name[16] = '.';
785 			cut_name[17] = '.';
786 			cut_name[18] = '.';
787 			cut_name[19] = '\0';
788 			/* cut off name for saving output style */
789 			pr_info("%20s ", cut_name);
790 		}
791 
792 		pr_info("%10u ", st->nr_acquired);
793 		pr_info("%10u ", st->nr_contended);
794 
795 		pr_info("%15" PRIu64 " ", st->avg_wait_time);
796 		pr_info("%15" PRIu64 " ", st->wait_time_total);
797 		pr_info("%15" PRIu64 " ", st->wait_time_max);
798 		pr_info("%15" PRIu64 " ", st->wait_time_min == ULLONG_MAX ?
799 		       0 : st->wait_time_min);
800 		pr_info("\n");
801 	}
802 
803 	print_bad_events(bad, total);
804 }
805 
806 static bool info_threads, info_map;
807 
808 static void dump_threads(void)
809 {
810 	struct thread_stat *st;
811 	struct rb_node *node;
812 	struct thread *t;
813 
814 	pr_info("%10s: comm\n", "Thread ID");
815 
816 	node = rb_first(&thread_stats);
817 	while (node) {
818 		st = container_of(node, struct thread_stat, rb);
819 		t = perf_session__findnew(session, st->tid);
820 		pr_info("%10d: %s\n", st->tid, thread__comm_str(t));
821 		node = rb_next(node);
822 		thread__put(t);
823 	}
824 }
825 
826 static int compare_maps(struct lock_stat *a, struct lock_stat *b)
827 {
828 	int ret;
829 
830 	if (a->name && b->name)
831 		ret = strcmp(a->name, b->name);
832 	else
833 		ret = !!a->name - !!b->name;
834 
835 	if (!ret)
836 		return a->addr < b->addr;
837 	else
838 		return ret < 0;
839 }
840 
841 static void dump_map(void)
842 {
843 	unsigned int i;
844 	struct lock_stat *st;
845 
846 	pr_info("Address of instance: name of class\n");
847 	for (i = 0; i < LOCKHASH_SIZE; i++) {
848 		hlist_for_each_entry(st, &lockhash_table[i], hash_entry) {
849 			insert_to_result(st, compare_maps);
850 		}
851 	}
852 
853 	while ((st = pop_from_result()))
854 		pr_info(" %#llx: %s\n", (unsigned long long)st->addr, st->name);
855 }
856 
857 static int dump_info(void)
858 {
859 	int rc = 0;
860 
861 	if (info_threads)
862 		dump_threads();
863 	else if (info_map)
864 		dump_map();
865 	else {
866 		rc = -1;
867 		pr_err("Unknown type of information\n");
868 	}
869 
870 	return rc;
871 }
872 
873 typedef int (*tracepoint_handler)(struct evsel *evsel,
874 				  struct perf_sample *sample);
875 
876 static int process_sample_event(struct perf_tool *tool __maybe_unused,
877 				union perf_event *event,
878 				struct perf_sample *sample,
879 				struct evsel *evsel,
880 				struct machine *machine)
881 {
882 	int err = 0;
883 	struct thread *thread = machine__findnew_thread(machine, sample->pid,
884 							sample->tid);
885 
886 	if (thread == NULL) {
887 		pr_debug("problem processing %d event, skipping it.\n",
888 			event->header.type);
889 		return -1;
890 	}
891 
892 	if (evsel->handler != NULL) {
893 		tracepoint_handler f = evsel->handler;
894 		err = f(evsel, sample);
895 	}
896 
897 	thread__put(thread);
898 
899 	return err;
900 }
901 
902 static void combine_result(void)
903 {
904 	unsigned int i;
905 	struct lock_stat *st;
906 
907 	if (!combine_locks)
908 		return;
909 
910 	for (i = 0; i < LOCKHASH_SIZE; i++) {
911 		hlist_for_each_entry(st, &lockhash_table[i], hash_entry) {
912 			combine_lock_stats(st);
913 		}
914 	}
915 }
916 
917 static void sort_result(void)
918 {
919 	unsigned int i;
920 	struct lock_stat *st;
921 
922 	for (i = 0; i < LOCKHASH_SIZE; i++) {
923 		hlist_for_each_entry(st, &lockhash_table[i], hash_entry) {
924 			insert_to_result(st, compare);
925 		}
926 	}
927 }
928 
929 static const struct evsel_str_handler lock_tracepoints[] = {
930 	{ "lock:lock_acquire",	 evsel__process_lock_acquire,   }, /* CONFIG_LOCKDEP */
931 	{ "lock:lock_acquired",	 evsel__process_lock_acquired,  }, /* CONFIG_LOCKDEP, CONFIG_LOCK_STAT */
932 	{ "lock:lock_contended", evsel__process_lock_contended, }, /* CONFIG_LOCKDEP, CONFIG_LOCK_STAT */
933 	{ "lock:lock_release",	 evsel__process_lock_release,   }, /* CONFIG_LOCKDEP */
934 };
935 
936 static bool force;
937 
938 static int __cmd_report(bool display_info)
939 {
940 	int err = -EINVAL;
941 	struct perf_tool eops = {
942 		.sample		 = process_sample_event,
943 		.comm		 = perf_event__process_comm,
944 		.namespaces	 = perf_event__process_namespaces,
945 		.ordered_events	 = true,
946 	};
947 	struct perf_data data = {
948 		.path  = input_name,
949 		.mode  = PERF_DATA_MODE_READ,
950 		.force = force,
951 	};
952 
953 	session = perf_session__new(&data, &eops);
954 	if (IS_ERR(session)) {
955 		pr_err("Initializing perf session failed\n");
956 		return PTR_ERR(session);
957 	}
958 
959 	symbol__init(&session->header.env);
960 
961 	if (!perf_session__has_traces(session, "lock record"))
962 		goto out_delete;
963 
964 	if (perf_session__set_tracepoints_handlers(session, lock_tracepoints)) {
965 		pr_err("Initializing perf session tracepoint handlers failed\n");
966 		goto out_delete;
967 	}
968 
969 	if (select_key())
970 		goto out_delete;
971 
972 	err = perf_session__process_events(session);
973 	if (err)
974 		goto out_delete;
975 
976 	setup_pager();
977 	if (display_info) /* used for info subcommand */
978 		err = dump_info();
979 	else {
980 		combine_result();
981 		sort_result();
982 		print_result();
983 	}
984 
985 out_delete:
986 	perf_session__delete(session);
987 	return err;
988 }
989 
990 static int __cmd_record(int argc, const char **argv)
991 {
992 	const char *record_args[] = {
993 		"record", "-R", "-m", "1024", "-c", "1",
994 	};
995 	unsigned int rec_argc, i, j, ret;
996 	const char **rec_argv;
997 
998 	for (i = 0; i < ARRAY_SIZE(lock_tracepoints); i++) {
999 		if (!is_valid_tracepoint(lock_tracepoints[i].name)) {
1000 				pr_err("tracepoint %s is not enabled. "
1001 				       "Are CONFIG_LOCKDEP and CONFIG_LOCK_STAT enabled?\n",
1002 				       lock_tracepoints[i].name);
1003 				return 1;
1004 		}
1005 	}
1006 
1007 	rec_argc = ARRAY_SIZE(record_args) + argc - 1;
1008 	/* factor of 2 is for -e in front of each tracepoint */
1009 	rec_argc += 2 * ARRAY_SIZE(lock_tracepoints);
1010 
1011 	rec_argv = calloc(rec_argc + 1, sizeof(char *));
1012 	if (!rec_argv)
1013 		return -ENOMEM;
1014 
1015 	for (i = 0; i < ARRAY_SIZE(record_args); i++)
1016 		rec_argv[i] = strdup(record_args[i]);
1017 
1018 	for (j = 0; j < ARRAY_SIZE(lock_tracepoints); j++) {
1019 		rec_argv[i++] = "-e";
1020 		rec_argv[i++] = strdup(lock_tracepoints[j].name);
1021 	}
1022 
1023 	for (j = 1; j < (unsigned int)argc; j++, i++)
1024 		rec_argv[i] = argv[j];
1025 
1026 	BUG_ON(i != rec_argc);
1027 
1028 	ret = cmd_record(i, rec_argv);
1029 	free(rec_argv);
1030 	return ret;
1031 }
1032 
1033 int cmd_lock(int argc, const char **argv)
1034 {
1035 	const struct option lock_options[] = {
1036 	OPT_STRING('i', "input", &input_name, "file", "input file name"),
1037 	OPT_INCR('v', "verbose", &verbose, "be more verbose (show symbol address, etc)"),
1038 	OPT_BOOLEAN('D', "dump-raw-trace", &dump_trace, "dump raw trace in ASCII"),
1039 	OPT_BOOLEAN('f', "force", &force, "don't complain, do it"),
1040 	OPT_END()
1041 	};
1042 
1043 	const struct option info_options[] = {
1044 	OPT_BOOLEAN('t', "threads", &info_threads,
1045 		    "dump thread list in perf.data"),
1046 	OPT_BOOLEAN('m', "map", &info_map,
1047 		    "map of lock instances (address:name table)"),
1048 	OPT_PARENT(lock_options)
1049 	};
1050 
1051 	const struct option report_options[] = {
1052 	OPT_STRING('k', "key", &sort_key, "acquired",
1053 		    "key for sorting (acquired / contended / avg_wait / wait_total / wait_max / wait_min)"),
1054 	/* TODO: type */
1055 	OPT_BOOLEAN('c', "combine-locks", &combine_locks,
1056 		    "combine locks in the same class"),
1057 	OPT_PARENT(lock_options)
1058 	};
1059 
1060 	const char * const info_usage[] = {
1061 		"perf lock info [<options>]",
1062 		NULL
1063 	};
1064 	const char *const lock_subcommands[] = { "record", "report", "script",
1065 						 "info", NULL };
1066 	const char *lock_usage[] = {
1067 		NULL,
1068 		NULL
1069 	};
1070 	const char * const report_usage[] = {
1071 		"perf lock report [<options>]",
1072 		NULL
1073 	};
1074 	unsigned int i;
1075 	int rc = 0;
1076 
1077 	for (i = 0; i < LOCKHASH_SIZE; i++)
1078 		INIT_HLIST_HEAD(lockhash_table + i);
1079 
1080 	argc = parse_options_subcommand(argc, argv, lock_options, lock_subcommands,
1081 					lock_usage, PARSE_OPT_STOP_AT_NON_OPTION);
1082 	if (!argc)
1083 		usage_with_options(lock_usage, lock_options);
1084 
1085 	if (!strncmp(argv[0], "rec", 3)) {
1086 		return __cmd_record(argc, argv);
1087 	} else if (!strncmp(argv[0], "report", 6)) {
1088 		trace_handler = &report_lock_ops;
1089 		if (argc) {
1090 			argc = parse_options(argc, argv,
1091 					     report_options, report_usage, 0);
1092 			if (argc)
1093 				usage_with_options(report_usage, report_options);
1094 		}
1095 		rc = __cmd_report(false);
1096 	} else if (!strcmp(argv[0], "script")) {
1097 		/* Aliased to 'perf script' */
1098 		return cmd_script(argc, argv);
1099 	} else if (!strcmp(argv[0], "info")) {
1100 		if (argc) {
1101 			argc = parse_options(argc, argv,
1102 					     info_options, info_usage, 0);
1103 			if (argc)
1104 				usage_with_options(info_usage, info_options);
1105 		}
1106 		/* recycling report_lock_ops */
1107 		trace_handler = &report_lock_ops;
1108 		rc = __cmd_report(true);
1109 	} else {
1110 		usage_with_options(lock_usage, lock_options);
1111 	}
1112 
1113 	return rc;
1114 }
1115