xref: /linux/tools/perf/builtin-lock.c (revision b8fd76f41820951d8a6e2521c25f54afadf338bd)
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 #include "util/target.h"
13 #include "util/callchain.h"
14 #include "util/lock-contention.h"
15 #include "util/bpf_skel/lock_data.h"
16 
17 #include <subcmd/pager.h>
18 #include <subcmd/parse-options.h>
19 #include "util/trace-event.h"
20 #include "util/tracepoint.h"
21 
22 #include "util/debug.h"
23 #include "util/session.h"
24 #include "util/tool.h"
25 #include "util/data.h"
26 #include "util/string2.h"
27 #include "util/map.h"
28 #include "util/util.h"
29 
30 #include <sys/types.h>
31 #include <sys/prctl.h>
32 #include <semaphore.h>
33 #include <math.h>
34 #include <limits.h>
35 
36 #include <linux/list.h>
37 #include <linux/hash.h>
38 #include <linux/kernel.h>
39 #include <linux/zalloc.h>
40 #include <linux/err.h>
41 #include <linux/stringify.h>
42 
43 static struct perf_session *session;
44 static struct target target;
45 
46 /* based on kernel/lockdep.c */
47 #define LOCKHASH_BITS		12
48 #define LOCKHASH_SIZE		(1UL << LOCKHASH_BITS)
49 
50 static struct hlist_head lockhash_table[LOCKHASH_SIZE];
51 
52 #define __lockhashfn(key)	hash_long((unsigned long)key, LOCKHASH_BITS)
53 #define lockhashentry(key)	(lockhash_table + __lockhashfn((key)))
54 
55 static struct rb_root		thread_stats;
56 
57 static bool combine_locks;
58 static bool show_thread_stats;
59 static bool show_lock_addrs;
60 static bool use_bpf;
61 static unsigned long bpf_map_entries = 10240;
62 static int max_stack_depth = CONTENTION_STACK_DEPTH;
63 static int stack_skip = CONTENTION_STACK_SKIP;
64 static int print_nr_entries = INT_MAX / 2;
65 
66 static enum lock_aggr_mode aggr_mode = LOCK_AGGR_ADDR;
67 
68 static struct thread_stat *thread_stat_find(u32 tid)
69 {
70 	struct rb_node *node;
71 	struct thread_stat *st;
72 
73 	node = thread_stats.rb_node;
74 	while (node) {
75 		st = container_of(node, struct thread_stat, rb);
76 		if (st->tid == tid)
77 			return st;
78 		else if (tid < st->tid)
79 			node = node->rb_left;
80 		else
81 			node = node->rb_right;
82 	}
83 
84 	return NULL;
85 }
86 
87 static void thread_stat_insert(struct thread_stat *new)
88 {
89 	struct rb_node **rb = &thread_stats.rb_node;
90 	struct rb_node *parent = NULL;
91 	struct thread_stat *p;
92 
93 	while (*rb) {
94 		p = container_of(*rb, struct thread_stat, rb);
95 		parent = *rb;
96 
97 		if (new->tid < p->tid)
98 			rb = &(*rb)->rb_left;
99 		else if (new->tid > p->tid)
100 			rb = &(*rb)->rb_right;
101 		else
102 			BUG_ON("inserting invalid thread_stat\n");
103 	}
104 
105 	rb_link_node(&new->rb, parent, rb);
106 	rb_insert_color(&new->rb, &thread_stats);
107 }
108 
109 static struct thread_stat *thread_stat_findnew_after_first(u32 tid)
110 {
111 	struct thread_stat *st;
112 
113 	st = thread_stat_find(tid);
114 	if (st)
115 		return st;
116 
117 	st = zalloc(sizeof(struct thread_stat));
118 	if (!st) {
119 		pr_err("memory allocation failed\n");
120 		return NULL;
121 	}
122 
123 	st->tid = tid;
124 	INIT_LIST_HEAD(&st->seq_list);
125 
126 	thread_stat_insert(st);
127 
128 	return st;
129 }
130 
131 static struct thread_stat *thread_stat_findnew_first(u32 tid);
132 static struct thread_stat *(*thread_stat_findnew)(u32 tid) =
133 	thread_stat_findnew_first;
134 
135 static struct thread_stat *thread_stat_findnew_first(u32 tid)
136 {
137 	struct thread_stat *st;
138 
139 	st = zalloc(sizeof(struct thread_stat));
140 	if (!st) {
141 		pr_err("memory allocation failed\n");
142 		return NULL;
143 	}
144 	st->tid = tid;
145 	INIT_LIST_HEAD(&st->seq_list);
146 
147 	rb_link_node(&st->rb, NULL, &thread_stats.rb_node);
148 	rb_insert_color(&st->rb, &thread_stats);
149 
150 	thread_stat_findnew = thread_stat_findnew_after_first;
151 	return st;
152 }
153 
154 /* build simple key function one is bigger than two */
155 #define SINGLE_KEY(member)						\
156 	static int lock_stat_key_ ## member(struct lock_stat *one,	\
157 					 struct lock_stat *two)		\
158 	{								\
159 		return one->member > two->member;			\
160 	}
161 
162 SINGLE_KEY(nr_acquired)
163 SINGLE_KEY(nr_contended)
164 SINGLE_KEY(avg_wait_time)
165 SINGLE_KEY(wait_time_total)
166 SINGLE_KEY(wait_time_max)
167 
168 static int lock_stat_key_wait_time_min(struct lock_stat *one,
169 					struct lock_stat *two)
170 {
171 	u64 s1 = one->wait_time_min;
172 	u64 s2 = two->wait_time_min;
173 	if (s1 == ULLONG_MAX)
174 		s1 = 0;
175 	if (s2 == ULLONG_MAX)
176 		s2 = 0;
177 	return s1 > s2;
178 }
179 
180 struct lock_key {
181 	/*
182 	 * name: the value for specify by user
183 	 * this should be simpler than raw name of member
184 	 * e.g. nr_acquired -> acquired, wait_time_total -> wait_total
185 	 */
186 	const char		*name;
187 	/* header: the string printed on the header line */
188 	const char		*header;
189 	/* len: the printing width of the field */
190 	int			len;
191 	/* key: a pointer to function to compare two lock stats for sorting */
192 	int			(*key)(struct lock_stat*, struct lock_stat*);
193 	/* print: a pointer to function to print a given lock stats */
194 	void			(*print)(struct lock_key*, struct lock_stat*);
195 	/* list: list entry to link this */
196 	struct list_head	list;
197 };
198 
199 static void lock_stat_key_print_time(unsigned long long nsec, int len)
200 {
201 	static const struct {
202 		float base;
203 		const char *unit;
204 	} table[] = {
205 		{ 1e9 * 3600, "h " },
206 		{ 1e9 * 60, "m " },
207 		{ 1e9, "s " },
208 		{ 1e6, "ms" },
209 		{ 1e3, "us" },
210 		{ 0, NULL },
211 	};
212 
213 	for (int i = 0; table[i].unit; i++) {
214 		if (nsec < table[i].base)
215 			continue;
216 
217 		pr_info("%*.2f %s", len - 3, nsec / table[i].base, table[i].unit);
218 		return;
219 	}
220 
221 	pr_info("%*llu %s", len - 3, nsec, "ns");
222 }
223 
224 #define PRINT_KEY(member)						\
225 static void lock_stat_key_print_ ## member(struct lock_key *key,	\
226 					   struct lock_stat *ls)	\
227 {									\
228 	pr_info("%*llu", key->len, (unsigned long long)ls->member);	\
229 }
230 
231 #define PRINT_TIME(member)						\
232 static void lock_stat_key_print_ ## member(struct lock_key *key,	\
233 					   struct lock_stat *ls)	\
234 {									\
235 	lock_stat_key_print_time((unsigned long long)ls->member, key->len);	\
236 }
237 
238 PRINT_KEY(nr_acquired)
239 PRINT_KEY(nr_contended)
240 PRINT_TIME(avg_wait_time)
241 PRINT_TIME(wait_time_total)
242 PRINT_TIME(wait_time_max)
243 
244 static void lock_stat_key_print_wait_time_min(struct lock_key *key,
245 					      struct lock_stat *ls)
246 {
247 	u64 wait_time = ls->wait_time_min;
248 
249 	if (wait_time == ULLONG_MAX)
250 		wait_time = 0;
251 
252 	lock_stat_key_print_time(wait_time, key->len);
253 }
254 
255 
256 static const char		*sort_key = "acquired";
257 
258 static int			(*compare)(struct lock_stat *, struct lock_stat *);
259 
260 static struct rb_root		sorted; /* place to store intermediate data */
261 static struct rb_root		result;	/* place to store sorted data */
262 
263 static LIST_HEAD(lock_keys);
264 static const char		*output_fields;
265 
266 #define DEF_KEY_LOCK(name, header, fn_suffix, len)			\
267 	{ #name, header, len, lock_stat_key_ ## fn_suffix, lock_stat_key_print_ ## fn_suffix, {} }
268 static struct lock_key report_keys[] = {
269 	DEF_KEY_LOCK(acquired, "acquired", nr_acquired, 10),
270 	DEF_KEY_LOCK(contended, "contended", nr_contended, 10),
271 	DEF_KEY_LOCK(avg_wait, "avg wait", avg_wait_time, 12),
272 	DEF_KEY_LOCK(wait_total, "total wait", wait_time_total, 12),
273 	DEF_KEY_LOCK(wait_max, "max wait", wait_time_max, 12),
274 	DEF_KEY_LOCK(wait_min, "min wait", wait_time_min, 12),
275 
276 	/* extra comparisons much complicated should be here */
277 	{ }
278 };
279 
280 static struct lock_key contention_keys[] = {
281 	DEF_KEY_LOCK(contended, "contended", nr_contended, 10),
282 	DEF_KEY_LOCK(wait_total, "total wait", wait_time_total, 12),
283 	DEF_KEY_LOCK(wait_max, "max wait", wait_time_max, 12),
284 	DEF_KEY_LOCK(wait_min, "min wait", wait_time_min, 12),
285 	DEF_KEY_LOCK(avg_wait, "avg wait", avg_wait_time, 12),
286 
287 	/* extra comparisons much complicated should be here */
288 	{ }
289 };
290 
291 static int select_key(bool contention)
292 {
293 	int i;
294 	struct lock_key *keys = report_keys;
295 
296 	if (contention)
297 		keys = contention_keys;
298 
299 	for (i = 0; keys[i].name; i++) {
300 		if (!strcmp(keys[i].name, sort_key)) {
301 			compare = keys[i].key;
302 
303 			/* selected key should be in the output fields */
304 			if (list_empty(&keys[i].list))
305 				list_add_tail(&keys[i].list, &lock_keys);
306 
307 			return 0;
308 		}
309 	}
310 
311 	pr_err("Unknown compare key: %s\n", sort_key);
312 	return -1;
313 }
314 
315 static int add_output_field(bool contention, char *name)
316 {
317 	int i;
318 	struct lock_key *keys = report_keys;
319 
320 	if (contention)
321 		keys = contention_keys;
322 
323 	for (i = 0; keys[i].name; i++) {
324 		if (strcmp(keys[i].name, name))
325 			continue;
326 
327 		/* prevent double link */
328 		if (list_empty(&keys[i].list))
329 			list_add_tail(&keys[i].list, &lock_keys);
330 
331 		return 0;
332 	}
333 
334 	pr_err("Unknown output field: %s\n", name);
335 	return -1;
336 }
337 
338 static int setup_output_field(bool contention, const char *str)
339 {
340 	char *tok, *tmp, *orig;
341 	int i, ret = 0;
342 	struct lock_key *keys = report_keys;
343 
344 	if (contention)
345 		keys = contention_keys;
346 
347 	/* no output field given: use all of them */
348 	if (str == NULL) {
349 		for (i = 0; keys[i].name; i++)
350 			list_add_tail(&keys[i].list, &lock_keys);
351 		return 0;
352 	}
353 
354 	for (i = 0; keys[i].name; i++)
355 		INIT_LIST_HEAD(&keys[i].list);
356 
357 	orig = tmp = strdup(str);
358 	if (orig == NULL)
359 		return -ENOMEM;
360 
361 	while ((tok = strsep(&tmp, ",")) != NULL){
362 		ret = add_output_field(contention, tok);
363 		if (ret < 0)
364 			break;
365 	}
366 	free(orig);
367 
368 	return ret;
369 }
370 
371 static void combine_lock_stats(struct lock_stat *st)
372 {
373 	struct rb_node **rb = &sorted.rb_node;
374 	struct rb_node *parent = NULL;
375 	struct lock_stat *p;
376 	int ret;
377 
378 	while (*rb) {
379 		p = container_of(*rb, struct lock_stat, rb);
380 		parent = *rb;
381 
382 		if (st->name && p->name)
383 			ret = strcmp(st->name, p->name);
384 		else
385 			ret = !!st->name - !!p->name;
386 
387 		if (ret == 0) {
388 			p->nr_acquired += st->nr_acquired;
389 			p->nr_contended += st->nr_contended;
390 			p->wait_time_total += st->wait_time_total;
391 
392 			if (p->nr_contended)
393 				p->avg_wait_time = p->wait_time_total / p->nr_contended;
394 
395 			if (p->wait_time_min > st->wait_time_min)
396 				p->wait_time_min = st->wait_time_min;
397 			if (p->wait_time_max < st->wait_time_max)
398 				p->wait_time_max = st->wait_time_max;
399 
400 			p->broken |= st->broken;
401 			st->combined = 1;
402 			return;
403 		}
404 
405 		if (ret < 0)
406 			rb = &(*rb)->rb_left;
407 		else
408 			rb = &(*rb)->rb_right;
409 	}
410 
411 	rb_link_node(&st->rb, parent, rb);
412 	rb_insert_color(&st->rb, &sorted);
413 }
414 
415 static void insert_to_result(struct lock_stat *st,
416 			     int (*bigger)(struct lock_stat *, struct lock_stat *))
417 {
418 	struct rb_node **rb = &result.rb_node;
419 	struct rb_node *parent = NULL;
420 	struct lock_stat *p;
421 
422 	if (combine_locks && st->combined)
423 		return;
424 
425 	while (*rb) {
426 		p = container_of(*rb, struct lock_stat, rb);
427 		parent = *rb;
428 
429 		if (bigger(st, p))
430 			rb = &(*rb)->rb_left;
431 		else
432 			rb = &(*rb)->rb_right;
433 	}
434 
435 	rb_link_node(&st->rb, parent, rb);
436 	rb_insert_color(&st->rb, &result);
437 }
438 
439 /* returns left most element of result, and erase it */
440 static struct lock_stat *pop_from_result(void)
441 {
442 	struct rb_node *node = result.rb_node;
443 
444 	if (!node)
445 		return NULL;
446 
447 	while (node->rb_left)
448 		node = node->rb_left;
449 
450 	rb_erase(node, &result);
451 	return container_of(node, struct lock_stat, rb);
452 }
453 
454 static struct lock_stat *lock_stat_find(u64 addr)
455 {
456 	struct hlist_head *entry = lockhashentry(addr);
457 	struct lock_stat *ret;
458 
459 	hlist_for_each_entry(ret, entry, hash_entry) {
460 		if (ret->addr == addr)
461 			return ret;
462 	}
463 	return NULL;
464 }
465 
466 static struct lock_stat *lock_stat_findnew(u64 addr, const char *name, int flags)
467 {
468 	struct hlist_head *entry = lockhashentry(addr);
469 	struct lock_stat *ret, *new;
470 
471 	hlist_for_each_entry(ret, entry, hash_entry) {
472 		if (ret->addr == addr)
473 			return ret;
474 	}
475 
476 	new = zalloc(sizeof(struct lock_stat));
477 	if (!new)
478 		goto alloc_failed;
479 
480 	new->addr = addr;
481 	new->name = strdup(name);
482 	if (!new->name) {
483 		free(new);
484 		goto alloc_failed;
485 	}
486 
487 	new->flags = flags;
488 	new->wait_time_min = ULLONG_MAX;
489 
490 	hlist_add_head(&new->hash_entry, entry);
491 	return new;
492 
493 alloc_failed:
494 	pr_err("memory allocation failed\n");
495 	return NULL;
496 }
497 
498 struct trace_lock_handler {
499 	/* it's used on CONFIG_LOCKDEP */
500 	int (*acquire_event)(struct evsel *evsel,
501 			     struct perf_sample *sample);
502 
503 	/* it's used on CONFIG_LOCKDEP && CONFIG_LOCK_STAT */
504 	int (*acquired_event)(struct evsel *evsel,
505 			      struct perf_sample *sample);
506 
507 	/* it's used on CONFIG_LOCKDEP && CONFIG_LOCK_STAT */
508 	int (*contended_event)(struct evsel *evsel,
509 			       struct perf_sample *sample);
510 
511 	/* it's used on CONFIG_LOCKDEP */
512 	int (*release_event)(struct evsel *evsel,
513 			     struct perf_sample *sample);
514 
515 	/* it's used when CONFIG_LOCKDEP is off */
516 	int (*contention_begin_event)(struct evsel *evsel,
517 				      struct perf_sample *sample);
518 
519 	/* it's used when CONFIG_LOCKDEP is off */
520 	int (*contention_end_event)(struct evsel *evsel,
521 				    struct perf_sample *sample);
522 };
523 
524 static struct lock_seq_stat *get_seq(struct thread_stat *ts, u64 addr)
525 {
526 	struct lock_seq_stat *seq;
527 
528 	list_for_each_entry(seq, &ts->seq_list, list) {
529 		if (seq->addr == addr)
530 			return seq;
531 	}
532 
533 	seq = zalloc(sizeof(struct lock_seq_stat));
534 	if (!seq) {
535 		pr_err("memory allocation failed\n");
536 		return NULL;
537 	}
538 	seq->state = SEQ_STATE_UNINITIALIZED;
539 	seq->addr = addr;
540 
541 	list_add(&seq->list, &ts->seq_list);
542 	return seq;
543 }
544 
545 enum broken_state {
546 	BROKEN_ACQUIRE,
547 	BROKEN_ACQUIRED,
548 	BROKEN_CONTENDED,
549 	BROKEN_RELEASE,
550 	BROKEN_MAX,
551 };
552 
553 static int bad_hist[BROKEN_MAX];
554 
555 enum acquire_flags {
556 	TRY_LOCK = 1,
557 	READ_LOCK = 2,
558 };
559 
560 static int get_key_by_aggr_mode_simple(u64 *key, u64 addr, u32 tid)
561 {
562 	switch (aggr_mode) {
563 	case LOCK_AGGR_ADDR:
564 		*key = addr;
565 		break;
566 	case LOCK_AGGR_TASK:
567 		*key = tid;
568 		break;
569 	case LOCK_AGGR_CALLER:
570 	default:
571 		pr_err("Invalid aggregation mode: %d\n", aggr_mode);
572 		return -EINVAL;
573 	}
574 	return 0;
575 }
576 
577 static u64 callchain_id(struct evsel *evsel, struct perf_sample *sample);
578 
579 static int get_key_by_aggr_mode(u64 *key, u64 addr, struct evsel *evsel,
580 				 struct perf_sample *sample)
581 {
582 	if (aggr_mode == LOCK_AGGR_CALLER) {
583 		*key = callchain_id(evsel, sample);
584 		return 0;
585 	}
586 	return get_key_by_aggr_mode_simple(key, addr, sample->tid);
587 }
588 
589 static int report_lock_acquire_event(struct evsel *evsel,
590 				     struct perf_sample *sample)
591 {
592 	struct lock_stat *ls;
593 	struct thread_stat *ts;
594 	struct lock_seq_stat *seq;
595 	const char *name = evsel__strval(evsel, sample, "name");
596 	u64 addr = evsel__intval(evsel, sample, "lockdep_addr");
597 	int flag = evsel__intval(evsel, sample, "flags");
598 	u64 key;
599 	int ret;
600 
601 	ret = get_key_by_aggr_mode_simple(&key, addr, sample->tid);
602 	if (ret < 0)
603 		return ret;
604 
605 	ls = lock_stat_findnew(key, name, 0);
606 	if (!ls)
607 		return -ENOMEM;
608 
609 	ts = thread_stat_findnew(sample->tid);
610 	if (!ts)
611 		return -ENOMEM;
612 
613 	seq = get_seq(ts, addr);
614 	if (!seq)
615 		return -ENOMEM;
616 
617 	switch (seq->state) {
618 	case SEQ_STATE_UNINITIALIZED:
619 	case SEQ_STATE_RELEASED:
620 		if (!flag) {
621 			seq->state = SEQ_STATE_ACQUIRING;
622 		} else {
623 			if (flag & TRY_LOCK)
624 				ls->nr_trylock++;
625 			if (flag & READ_LOCK)
626 				ls->nr_readlock++;
627 			seq->state = SEQ_STATE_READ_ACQUIRED;
628 			seq->read_count = 1;
629 			ls->nr_acquired++;
630 		}
631 		break;
632 	case SEQ_STATE_READ_ACQUIRED:
633 		if (flag & READ_LOCK) {
634 			seq->read_count++;
635 			ls->nr_acquired++;
636 			goto end;
637 		} else {
638 			goto broken;
639 		}
640 		break;
641 	case SEQ_STATE_ACQUIRED:
642 	case SEQ_STATE_ACQUIRING:
643 	case SEQ_STATE_CONTENDED:
644 broken:
645 		/* broken lock sequence */
646 		if (!ls->broken) {
647 			ls->broken = 1;
648 			bad_hist[BROKEN_ACQUIRE]++;
649 		}
650 		list_del_init(&seq->list);
651 		free(seq);
652 		goto end;
653 	default:
654 		BUG_ON("Unknown state of lock sequence found!\n");
655 		break;
656 	}
657 
658 	ls->nr_acquire++;
659 	seq->prev_event_time = sample->time;
660 end:
661 	return 0;
662 }
663 
664 static int report_lock_acquired_event(struct evsel *evsel,
665 				      struct perf_sample *sample)
666 {
667 	struct lock_stat *ls;
668 	struct thread_stat *ts;
669 	struct lock_seq_stat *seq;
670 	u64 contended_term;
671 	const char *name = evsel__strval(evsel, sample, "name");
672 	u64 addr = evsel__intval(evsel, sample, "lockdep_addr");
673 	u64 key;
674 	int ret;
675 
676 	ret = get_key_by_aggr_mode_simple(&key, addr, sample->tid);
677 	if (ret < 0)
678 		return ret;
679 
680 	ls = lock_stat_findnew(key, name, 0);
681 	if (!ls)
682 		return -ENOMEM;
683 
684 	ts = thread_stat_findnew(sample->tid);
685 	if (!ts)
686 		return -ENOMEM;
687 
688 	seq = get_seq(ts, addr);
689 	if (!seq)
690 		return -ENOMEM;
691 
692 	switch (seq->state) {
693 	case SEQ_STATE_UNINITIALIZED:
694 		/* orphan event, do nothing */
695 		return 0;
696 	case SEQ_STATE_ACQUIRING:
697 		break;
698 	case SEQ_STATE_CONTENDED:
699 		contended_term = sample->time - seq->prev_event_time;
700 		ls->wait_time_total += contended_term;
701 		if (contended_term < ls->wait_time_min)
702 			ls->wait_time_min = contended_term;
703 		if (ls->wait_time_max < contended_term)
704 			ls->wait_time_max = contended_term;
705 		break;
706 	case SEQ_STATE_RELEASED:
707 	case SEQ_STATE_ACQUIRED:
708 	case SEQ_STATE_READ_ACQUIRED:
709 		/* broken lock sequence */
710 		if (!ls->broken) {
711 			ls->broken = 1;
712 			bad_hist[BROKEN_ACQUIRED]++;
713 		}
714 		list_del_init(&seq->list);
715 		free(seq);
716 		goto end;
717 	default:
718 		BUG_ON("Unknown state of lock sequence found!\n");
719 		break;
720 	}
721 
722 	seq->state = SEQ_STATE_ACQUIRED;
723 	ls->nr_acquired++;
724 	ls->avg_wait_time = ls->nr_contended ? ls->wait_time_total/ls->nr_contended : 0;
725 	seq->prev_event_time = sample->time;
726 end:
727 	return 0;
728 }
729 
730 static int report_lock_contended_event(struct evsel *evsel,
731 				       struct perf_sample *sample)
732 {
733 	struct lock_stat *ls;
734 	struct thread_stat *ts;
735 	struct lock_seq_stat *seq;
736 	const char *name = evsel__strval(evsel, sample, "name");
737 	u64 addr = evsel__intval(evsel, sample, "lockdep_addr");
738 	u64 key;
739 	int ret;
740 
741 	ret = get_key_by_aggr_mode_simple(&key, addr, sample->tid);
742 	if (ret < 0)
743 		return ret;
744 
745 	ls = lock_stat_findnew(key, name, 0);
746 	if (!ls)
747 		return -ENOMEM;
748 
749 	ts = thread_stat_findnew(sample->tid);
750 	if (!ts)
751 		return -ENOMEM;
752 
753 	seq = get_seq(ts, addr);
754 	if (!seq)
755 		return -ENOMEM;
756 
757 	switch (seq->state) {
758 	case SEQ_STATE_UNINITIALIZED:
759 		/* orphan event, do nothing */
760 		return 0;
761 	case SEQ_STATE_ACQUIRING:
762 		break;
763 	case SEQ_STATE_RELEASED:
764 	case SEQ_STATE_ACQUIRED:
765 	case SEQ_STATE_READ_ACQUIRED:
766 	case SEQ_STATE_CONTENDED:
767 		/* broken lock sequence */
768 		if (!ls->broken) {
769 			ls->broken = 1;
770 			bad_hist[BROKEN_CONTENDED]++;
771 		}
772 		list_del_init(&seq->list);
773 		free(seq);
774 		goto end;
775 	default:
776 		BUG_ON("Unknown state of lock sequence found!\n");
777 		break;
778 	}
779 
780 	seq->state = SEQ_STATE_CONTENDED;
781 	ls->nr_contended++;
782 	ls->avg_wait_time = ls->wait_time_total/ls->nr_contended;
783 	seq->prev_event_time = sample->time;
784 end:
785 	return 0;
786 }
787 
788 static int report_lock_release_event(struct evsel *evsel,
789 				     struct perf_sample *sample)
790 {
791 	struct lock_stat *ls;
792 	struct thread_stat *ts;
793 	struct lock_seq_stat *seq;
794 	const char *name = evsel__strval(evsel, sample, "name");
795 	u64 addr = evsel__intval(evsel, sample, "lockdep_addr");
796 	u64 key;
797 	int ret;
798 
799 	ret = get_key_by_aggr_mode_simple(&key, addr, sample->tid);
800 	if (ret < 0)
801 		return ret;
802 
803 	ls = lock_stat_findnew(key, name, 0);
804 	if (!ls)
805 		return -ENOMEM;
806 
807 	ts = thread_stat_findnew(sample->tid);
808 	if (!ts)
809 		return -ENOMEM;
810 
811 	seq = get_seq(ts, addr);
812 	if (!seq)
813 		return -ENOMEM;
814 
815 	switch (seq->state) {
816 	case SEQ_STATE_UNINITIALIZED:
817 		goto end;
818 	case SEQ_STATE_ACQUIRED:
819 		break;
820 	case SEQ_STATE_READ_ACQUIRED:
821 		seq->read_count--;
822 		BUG_ON(seq->read_count < 0);
823 		if (seq->read_count) {
824 			ls->nr_release++;
825 			goto end;
826 		}
827 		break;
828 	case SEQ_STATE_ACQUIRING:
829 	case SEQ_STATE_CONTENDED:
830 	case SEQ_STATE_RELEASED:
831 		/* broken lock sequence */
832 		if (!ls->broken) {
833 			ls->broken = 1;
834 			bad_hist[BROKEN_RELEASE]++;
835 		}
836 		goto free_seq;
837 	default:
838 		BUG_ON("Unknown state of lock sequence found!\n");
839 		break;
840 	}
841 
842 	ls->nr_release++;
843 free_seq:
844 	list_del_init(&seq->list);
845 	free(seq);
846 end:
847 	return 0;
848 }
849 
850 static int get_symbol_name_offset(struct map *map, struct symbol *sym, u64 ip,
851 				  char *buf, int size)
852 {
853 	u64 offset;
854 
855 	if (map == NULL || sym == NULL) {
856 		buf[0] = '\0';
857 		return 0;
858 	}
859 
860 	offset = map->map_ip(map, ip) - sym->start;
861 
862 	if (offset)
863 		return scnprintf(buf, size, "%s+%#lx", sym->name, offset);
864 	else
865 		return strlcpy(buf, sym->name, size);
866 }
867 static int lock_contention_caller(struct evsel *evsel, struct perf_sample *sample,
868 				  char *buf, int size)
869 {
870 	struct thread *thread;
871 	struct callchain_cursor *cursor = &callchain_cursor;
872 	struct machine *machine = &session->machines.host;
873 	struct symbol *sym;
874 	int skip = 0;
875 	int ret;
876 
877 	/* lock names will be replaced to task name later */
878 	if (show_thread_stats)
879 		return -1;
880 
881 	thread = machine__findnew_thread(machine, -1, sample->pid);
882 	if (thread == NULL)
883 		return -1;
884 
885 	/* use caller function name from the callchain */
886 	ret = thread__resolve_callchain(thread, cursor, evsel, sample,
887 					NULL, NULL, max_stack_depth);
888 	if (ret != 0) {
889 		thread__put(thread);
890 		return -1;
891 	}
892 
893 	callchain_cursor_commit(cursor);
894 	thread__put(thread);
895 
896 	while (true) {
897 		struct callchain_cursor_node *node;
898 
899 		node = callchain_cursor_current(cursor);
900 		if (node == NULL)
901 			break;
902 
903 		/* skip first few entries - for lock functions */
904 		if (++skip <= stack_skip)
905 			goto next;
906 
907 		sym = node->ms.sym;
908 		if (sym && !machine__is_lock_function(machine, node->ip)) {
909 			get_symbol_name_offset(node->ms.map, sym, node->ip,
910 					       buf, size);
911 			return 0;
912 		}
913 
914 next:
915 		callchain_cursor_advance(cursor);
916 	}
917 	return -1;
918 }
919 
920 static u64 callchain_id(struct evsel *evsel, struct perf_sample *sample)
921 {
922 	struct callchain_cursor *cursor = &callchain_cursor;
923 	struct machine *machine = &session->machines.host;
924 	struct thread *thread;
925 	u64 hash = 0;
926 	int skip = 0;
927 	int ret;
928 
929 	thread = machine__findnew_thread(machine, -1, sample->pid);
930 	if (thread == NULL)
931 		return -1;
932 
933 	/* use caller function name from the callchain */
934 	ret = thread__resolve_callchain(thread, cursor, evsel, sample,
935 					NULL, NULL, max_stack_depth);
936 	thread__put(thread);
937 
938 	if (ret != 0)
939 		return -1;
940 
941 	callchain_cursor_commit(cursor);
942 
943 	while (true) {
944 		struct callchain_cursor_node *node;
945 
946 		node = callchain_cursor_current(cursor);
947 		if (node == NULL)
948 			break;
949 
950 		/* skip first few entries - for lock functions */
951 		if (++skip <= stack_skip)
952 			goto next;
953 
954 		if (node->ms.sym && machine__is_lock_function(machine, node->ip))
955 			goto next;
956 
957 		hash ^= hash_long((unsigned long)node->ip, 64);
958 
959 next:
960 		callchain_cursor_advance(cursor);
961 	}
962 	return hash;
963 }
964 
965 static u64 *get_callstack(struct perf_sample *sample, int max_stack)
966 {
967 	u64 *callstack;
968 	u64 i;
969 	int c;
970 
971 	callstack = calloc(max_stack, sizeof(*callstack));
972 	if (callstack == NULL)
973 		return NULL;
974 
975 	for (i = 0, c = 0; i < sample->callchain->nr && c < max_stack; i++) {
976 		u64 ip = sample->callchain->ips[i];
977 
978 		if (ip >= PERF_CONTEXT_MAX)
979 			continue;
980 
981 		callstack[c++] = ip;
982 	}
983 	return callstack;
984 }
985 
986 static int report_lock_contention_begin_event(struct evsel *evsel,
987 					      struct perf_sample *sample)
988 {
989 	struct lock_stat *ls;
990 	struct thread_stat *ts;
991 	struct lock_seq_stat *seq;
992 	u64 addr = evsel__intval(evsel, sample, "lock_addr");
993 	u64 key;
994 	int ret;
995 
996 	ret = get_key_by_aggr_mode(&key, addr, evsel, sample);
997 	if (ret < 0)
998 		return ret;
999 
1000 	ls = lock_stat_find(key);
1001 	if (!ls) {
1002 		char buf[128];
1003 		const char *name = "";
1004 		unsigned int flags = evsel__intval(evsel, sample, "flags");
1005 		struct machine *machine = &session->machines.host;
1006 		struct map *kmap;
1007 		struct symbol *sym;
1008 
1009 		switch (aggr_mode) {
1010 		case LOCK_AGGR_ADDR:
1011 			/* make sure it loads the kernel map to find lock symbols */
1012 			map__load(machine__kernel_map(machine));
1013 
1014 			sym = machine__find_kernel_symbol(machine, key, &kmap);
1015 			if (sym)
1016 				name = sym->name;
1017 			break;
1018 		case LOCK_AGGR_CALLER:
1019 			name = buf;
1020 			if (lock_contention_caller(evsel, sample, buf, sizeof(buf)) < 0)
1021 				name = "Unknown";
1022 			break;
1023 		case LOCK_AGGR_TASK:
1024 		default:
1025 			break;
1026 		}
1027 
1028 		ls = lock_stat_findnew(key, name, flags);
1029 		if (!ls)
1030 			return -ENOMEM;
1031 
1032 		if (aggr_mode == LOCK_AGGR_CALLER && verbose) {
1033 			ls->callstack = get_callstack(sample, max_stack_depth);
1034 			if (ls->callstack == NULL)
1035 				return -ENOMEM;
1036 		}
1037 	}
1038 
1039 	ts = thread_stat_findnew(sample->tid);
1040 	if (!ts)
1041 		return -ENOMEM;
1042 
1043 	seq = get_seq(ts, addr);
1044 	if (!seq)
1045 		return -ENOMEM;
1046 
1047 	switch (seq->state) {
1048 	case SEQ_STATE_UNINITIALIZED:
1049 	case SEQ_STATE_ACQUIRED:
1050 		break;
1051 	case SEQ_STATE_CONTENDED:
1052 		/*
1053 		 * It can have nested contention begin with mutex spinning,
1054 		 * then we would use the original contention begin event and
1055 		 * ignore the second one.
1056 		 */
1057 		goto end;
1058 	case SEQ_STATE_ACQUIRING:
1059 	case SEQ_STATE_READ_ACQUIRED:
1060 	case SEQ_STATE_RELEASED:
1061 		/* broken lock sequence */
1062 		if (!ls->broken) {
1063 			ls->broken = 1;
1064 			bad_hist[BROKEN_CONTENDED]++;
1065 		}
1066 		list_del_init(&seq->list);
1067 		free(seq);
1068 		goto end;
1069 	default:
1070 		BUG_ON("Unknown state of lock sequence found!\n");
1071 		break;
1072 	}
1073 
1074 	if (seq->state != SEQ_STATE_CONTENDED) {
1075 		seq->state = SEQ_STATE_CONTENDED;
1076 		seq->prev_event_time = sample->time;
1077 		ls->nr_contended++;
1078 	}
1079 end:
1080 	return 0;
1081 }
1082 
1083 static int report_lock_contention_end_event(struct evsel *evsel,
1084 					    struct perf_sample *sample)
1085 {
1086 	struct lock_stat *ls;
1087 	struct thread_stat *ts;
1088 	struct lock_seq_stat *seq;
1089 	u64 contended_term;
1090 	u64 addr = evsel__intval(evsel, sample, "lock_addr");
1091 	u64 key;
1092 	int ret;
1093 
1094 	ret = get_key_by_aggr_mode(&key, addr, evsel, sample);
1095 	if (ret < 0)
1096 		return ret;
1097 
1098 	ls = lock_stat_find(key);
1099 	if (!ls)
1100 		return 0;
1101 
1102 	ts = thread_stat_find(sample->tid);
1103 	if (!ts)
1104 		return 0;
1105 
1106 	seq = get_seq(ts, addr);
1107 	if (!seq)
1108 		return -ENOMEM;
1109 
1110 	switch (seq->state) {
1111 	case SEQ_STATE_UNINITIALIZED:
1112 		goto end;
1113 	case SEQ_STATE_CONTENDED:
1114 		contended_term = sample->time - seq->prev_event_time;
1115 		ls->wait_time_total += contended_term;
1116 		if (contended_term < ls->wait_time_min)
1117 			ls->wait_time_min = contended_term;
1118 		if (ls->wait_time_max < contended_term)
1119 			ls->wait_time_max = contended_term;
1120 		break;
1121 	case SEQ_STATE_ACQUIRING:
1122 	case SEQ_STATE_ACQUIRED:
1123 	case SEQ_STATE_READ_ACQUIRED:
1124 	case SEQ_STATE_RELEASED:
1125 		/* broken lock sequence */
1126 		if (!ls->broken) {
1127 			ls->broken = 1;
1128 			bad_hist[BROKEN_ACQUIRED]++;
1129 		}
1130 		list_del_init(&seq->list);
1131 		free(seq);
1132 		goto end;
1133 	default:
1134 		BUG_ON("Unknown state of lock sequence found!\n");
1135 		break;
1136 	}
1137 
1138 	seq->state = SEQ_STATE_ACQUIRED;
1139 	ls->nr_acquired++;
1140 	ls->avg_wait_time = ls->wait_time_total/ls->nr_acquired;
1141 end:
1142 	return 0;
1143 }
1144 
1145 /* lock oriented handlers */
1146 /* TODO: handlers for CPU oriented, thread oriented */
1147 static struct trace_lock_handler report_lock_ops  = {
1148 	.acquire_event		= report_lock_acquire_event,
1149 	.acquired_event		= report_lock_acquired_event,
1150 	.contended_event	= report_lock_contended_event,
1151 	.release_event		= report_lock_release_event,
1152 	.contention_begin_event	= report_lock_contention_begin_event,
1153 	.contention_end_event	= report_lock_contention_end_event,
1154 };
1155 
1156 static struct trace_lock_handler contention_lock_ops  = {
1157 	.contention_begin_event	= report_lock_contention_begin_event,
1158 	.contention_end_event	= report_lock_contention_end_event,
1159 };
1160 
1161 
1162 static struct trace_lock_handler *trace_handler;
1163 
1164 static int evsel__process_lock_acquire(struct evsel *evsel, struct perf_sample *sample)
1165 {
1166 	if (trace_handler->acquire_event)
1167 		return trace_handler->acquire_event(evsel, sample);
1168 	return 0;
1169 }
1170 
1171 static int evsel__process_lock_acquired(struct evsel *evsel, struct perf_sample *sample)
1172 {
1173 	if (trace_handler->acquired_event)
1174 		return trace_handler->acquired_event(evsel, sample);
1175 	return 0;
1176 }
1177 
1178 static int evsel__process_lock_contended(struct evsel *evsel, struct perf_sample *sample)
1179 {
1180 	if (trace_handler->contended_event)
1181 		return trace_handler->contended_event(evsel, sample);
1182 	return 0;
1183 }
1184 
1185 static int evsel__process_lock_release(struct evsel *evsel, struct perf_sample *sample)
1186 {
1187 	if (trace_handler->release_event)
1188 		return trace_handler->release_event(evsel, sample);
1189 	return 0;
1190 }
1191 
1192 static int evsel__process_contention_begin(struct evsel *evsel, struct perf_sample *sample)
1193 {
1194 	if (trace_handler->contention_begin_event)
1195 		return trace_handler->contention_begin_event(evsel, sample);
1196 	return 0;
1197 }
1198 
1199 static int evsel__process_contention_end(struct evsel *evsel, struct perf_sample *sample)
1200 {
1201 	if (trace_handler->contention_end_event)
1202 		return trace_handler->contention_end_event(evsel, sample);
1203 	return 0;
1204 }
1205 
1206 static void print_bad_events(int bad, int total)
1207 {
1208 	/* Output for debug, this have to be removed */
1209 	int i;
1210 	int broken = 0;
1211 	const char *name[4] =
1212 		{ "acquire", "acquired", "contended", "release" };
1213 
1214 	for (i = 0; i < BROKEN_MAX; i++)
1215 		broken += bad_hist[i];
1216 
1217 	if (quiet || (broken == 0 && !verbose))
1218 		return;
1219 
1220 	pr_info("\n=== output for debug===\n\n");
1221 	pr_info("bad: %d, total: %d\n", bad, total);
1222 	pr_info("bad rate: %.2f %%\n", (double)bad / (double)total * 100);
1223 	pr_info("histogram of events caused bad sequence\n");
1224 	for (i = 0; i < BROKEN_MAX; i++)
1225 		pr_info(" %10s: %d\n", name[i], bad_hist[i]);
1226 }
1227 
1228 /* TODO: various way to print, coloring, nano or milli sec */
1229 static void print_result(void)
1230 {
1231 	struct lock_stat *st;
1232 	struct lock_key *key;
1233 	char cut_name[20];
1234 	int bad, total, printed;
1235 
1236 	if (!quiet) {
1237 		pr_info("%20s ", "Name");
1238 		list_for_each_entry(key, &lock_keys, list)
1239 			pr_info("%*s ", key->len, key->header);
1240 		pr_info("\n\n");
1241 	}
1242 
1243 	bad = total = printed = 0;
1244 	while ((st = pop_from_result())) {
1245 		total++;
1246 		if (st->broken)
1247 			bad++;
1248 		if (!st->nr_acquired)
1249 			continue;
1250 
1251 		bzero(cut_name, 20);
1252 
1253 		if (strlen(st->name) < 20) {
1254 			/* output raw name */
1255 			const char *name = st->name;
1256 
1257 			if (show_thread_stats) {
1258 				struct thread *t;
1259 
1260 				/* st->addr contains tid of thread */
1261 				t = perf_session__findnew(session, st->addr);
1262 				name = thread__comm_str(t);
1263 			}
1264 
1265 			pr_info("%20s ", name);
1266 		} else {
1267 			strncpy(cut_name, st->name, 16);
1268 			cut_name[16] = '.';
1269 			cut_name[17] = '.';
1270 			cut_name[18] = '.';
1271 			cut_name[19] = '\0';
1272 			/* cut off name for saving output style */
1273 			pr_info("%20s ", cut_name);
1274 		}
1275 
1276 		list_for_each_entry(key, &lock_keys, list) {
1277 			key->print(key, st);
1278 			pr_info(" ");
1279 		}
1280 		pr_info("\n");
1281 
1282 		if (++printed >= print_nr_entries)
1283 			break;
1284 	}
1285 
1286 	print_bad_events(bad, total);
1287 }
1288 
1289 static bool info_threads, info_map;
1290 
1291 static void dump_threads(void)
1292 {
1293 	struct thread_stat *st;
1294 	struct rb_node *node;
1295 	struct thread *t;
1296 
1297 	pr_info("%10s: comm\n", "Thread ID");
1298 
1299 	node = rb_first(&thread_stats);
1300 	while (node) {
1301 		st = container_of(node, struct thread_stat, rb);
1302 		t = perf_session__findnew(session, st->tid);
1303 		pr_info("%10d: %s\n", st->tid, thread__comm_str(t));
1304 		node = rb_next(node);
1305 		thread__put(t);
1306 	}
1307 }
1308 
1309 static int compare_maps(struct lock_stat *a, struct lock_stat *b)
1310 {
1311 	int ret;
1312 
1313 	if (a->name && b->name)
1314 		ret = strcmp(a->name, b->name);
1315 	else
1316 		ret = !!a->name - !!b->name;
1317 
1318 	if (!ret)
1319 		return a->addr < b->addr;
1320 	else
1321 		return ret < 0;
1322 }
1323 
1324 static void dump_map(void)
1325 {
1326 	unsigned int i;
1327 	struct lock_stat *st;
1328 
1329 	pr_info("Address of instance: name of class\n");
1330 	for (i = 0; i < LOCKHASH_SIZE; i++) {
1331 		hlist_for_each_entry(st, &lockhash_table[i], hash_entry) {
1332 			insert_to_result(st, compare_maps);
1333 		}
1334 	}
1335 
1336 	while ((st = pop_from_result()))
1337 		pr_info(" %#llx: %s\n", (unsigned long long)st->addr, st->name);
1338 }
1339 
1340 static int dump_info(void)
1341 {
1342 	int rc = 0;
1343 
1344 	if (info_threads)
1345 		dump_threads();
1346 	else if (info_map)
1347 		dump_map();
1348 	else {
1349 		rc = -1;
1350 		pr_err("Unknown type of information\n");
1351 	}
1352 
1353 	return rc;
1354 }
1355 
1356 static const struct evsel_str_handler lock_tracepoints[] = {
1357 	{ "lock:lock_acquire",	 evsel__process_lock_acquire,   }, /* CONFIG_LOCKDEP */
1358 	{ "lock:lock_acquired",	 evsel__process_lock_acquired,  }, /* CONFIG_LOCKDEP, CONFIG_LOCK_STAT */
1359 	{ "lock:lock_contended", evsel__process_lock_contended, }, /* CONFIG_LOCKDEP, CONFIG_LOCK_STAT */
1360 	{ "lock:lock_release",	 evsel__process_lock_release,   }, /* CONFIG_LOCKDEP */
1361 };
1362 
1363 static const struct evsel_str_handler contention_tracepoints[] = {
1364 	{ "lock:contention_begin", evsel__process_contention_begin, },
1365 	{ "lock:contention_end",   evsel__process_contention_end,   },
1366 };
1367 
1368 static int process_event_update(struct perf_tool *tool,
1369 				union perf_event *event,
1370 				struct evlist **pevlist)
1371 {
1372 	int ret;
1373 
1374 	ret = perf_event__process_event_update(tool, event, pevlist);
1375 	if (ret < 0)
1376 		return ret;
1377 
1378 	/* this can return -EEXIST since we call it for each evsel */
1379 	perf_session__set_tracepoints_handlers(session, lock_tracepoints);
1380 	perf_session__set_tracepoints_handlers(session, contention_tracepoints);
1381 	return 0;
1382 }
1383 
1384 typedef int (*tracepoint_handler)(struct evsel *evsel,
1385 				  struct perf_sample *sample);
1386 
1387 static int process_sample_event(struct perf_tool *tool __maybe_unused,
1388 				union perf_event *event,
1389 				struct perf_sample *sample,
1390 				struct evsel *evsel,
1391 				struct machine *machine)
1392 {
1393 	int err = 0;
1394 	struct thread *thread = machine__findnew_thread(machine, sample->pid,
1395 							sample->tid);
1396 
1397 	if (thread == NULL) {
1398 		pr_debug("problem processing %d event, skipping it.\n",
1399 			event->header.type);
1400 		return -1;
1401 	}
1402 
1403 	if (evsel->handler != NULL) {
1404 		tracepoint_handler f = evsel->handler;
1405 		err = f(evsel, sample);
1406 	}
1407 
1408 	thread__put(thread);
1409 
1410 	return err;
1411 }
1412 
1413 static void combine_result(void)
1414 {
1415 	unsigned int i;
1416 	struct lock_stat *st;
1417 
1418 	if (!combine_locks)
1419 		return;
1420 
1421 	for (i = 0; i < LOCKHASH_SIZE; i++) {
1422 		hlist_for_each_entry(st, &lockhash_table[i], hash_entry) {
1423 			combine_lock_stats(st);
1424 		}
1425 	}
1426 }
1427 
1428 static void sort_result(void)
1429 {
1430 	unsigned int i;
1431 	struct lock_stat *st;
1432 
1433 	for (i = 0; i < LOCKHASH_SIZE; i++) {
1434 		hlist_for_each_entry(st, &lockhash_table[i], hash_entry) {
1435 			insert_to_result(st, compare);
1436 		}
1437 	}
1438 }
1439 
1440 static const char *get_type_str(struct lock_stat *st)
1441 {
1442 	static const struct {
1443 		unsigned int flags;
1444 		const char *name;
1445 	} table[] = {
1446 		{ 0,				"semaphore" },
1447 		{ LCB_F_SPIN,			"spinlock" },
1448 		{ LCB_F_SPIN | LCB_F_READ,	"rwlock:R" },
1449 		{ LCB_F_SPIN | LCB_F_WRITE,	"rwlock:W"},
1450 		{ LCB_F_READ,			"rwsem:R" },
1451 		{ LCB_F_WRITE,			"rwsem:W" },
1452 		{ LCB_F_RT,			"rtmutex" },
1453 		{ LCB_F_RT | LCB_F_READ,	"rwlock-rt:R" },
1454 		{ LCB_F_RT | LCB_F_WRITE,	"rwlock-rt:W"},
1455 		{ LCB_F_PERCPU | LCB_F_READ,	"pcpu-sem:R" },
1456 		{ LCB_F_PERCPU | LCB_F_WRITE,	"pcpu-sem:W" },
1457 		{ LCB_F_MUTEX,			"mutex" },
1458 		{ LCB_F_MUTEX | LCB_F_SPIN,	"mutex" },
1459 	};
1460 
1461 	for (unsigned int i = 0; i < ARRAY_SIZE(table); i++) {
1462 		if (table[i].flags == st->flags)
1463 			return table[i].name;
1464 	}
1465 	return "unknown";
1466 }
1467 
1468 static void sort_contention_result(void)
1469 {
1470 	sort_result();
1471 }
1472 
1473 static void print_contention_result(struct lock_contention *con)
1474 {
1475 	struct lock_stat *st;
1476 	struct lock_key *key;
1477 	int bad, total, printed;
1478 
1479 	if (!quiet) {
1480 		list_for_each_entry(key, &lock_keys, list)
1481 			pr_info("%*s ", key->len, key->header);
1482 
1483 		switch (aggr_mode) {
1484 		case LOCK_AGGR_TASK:
1485 			pr_info("  %10s   %s\n\n", "pid", "comm");
1486 			break;
1487 		case LOCK_AGGR_CALLER:
1488 			pr_info("  %10s   %s\n\n", "type", "caller");
1489 			break;
1490 		case LOCK_AGGR_ADDR:
1491 			pr_info("  %16s   %s\n\n", "address", "symbol");
1492 			break;
1493 		default:
1494 			break;
1495 		}
1496 	}
1497 
1498 	bad = total = printed = 0;
1499 	if (use_bpf)
1500 		bad = bad_hist[BROKEN_CONTENDED];
1501 
1502 	while ((st = pop_from_result())) {
1503 		struct thread *t;
1504 		int pid;
1505 
1506 		total += use_bpf ? st->nr_contended : 1;
1507 		if (st->broken)
1508 			bad++;
1509 
1510 		list_for_each_entry(key, &lock_keys, list) {
1511 			key->print(key, st);
1512 			pr_info(" ");
1513 		}
1514 
1515 		switch (aggr_mode) {
1516 		case LOCK_AGGR_CALLER:
1517 			pr_info("  %10s   %s\n", get_type_str(st), st->name);
1518 			break;
1519 		case LOCK_AGGR_TASK:
1520 			pid = st->addr;
1521 			t = perf_session__findnew(session, pid);
1522 			pr_info("  %10d   %s\n", pid, thread__comm_str(t));
1523 			break;
1524 		case LOCK_AGGR_ADDR:
1525 			pr_info("  %016llx   %s\n", (unsigned long long)st->addr,
1526 				st->name ? : "");
1527 			break;
1528 		default:
1529 			break;
1530 		}
1531 
1532 		if (aggr_mode == LOCK_AGGR_CALLER && verbose) {
1533 			struct map *kmap;
1534 			struct symbol *sym;
1535 			char buf[128];
1536 			u64 ip;
1537 
1538 			for (int i = 0; i < max_stack_depth; i++) {
1539 				if (!st->callstack || !st->callstack[i])
1540 					break;
1541 
1542 				ip = st->callstack[i];
1543 				sym = machine__find_kernel_symbol(con->machine, ip, &kmap);
1544 				get_symbol_name_offset(kmap, sym, ip, buf, sizeof(buf));
1545 				pr_info("\t\t\t%#lx  %s\n", (unsigned long)ip, buf);
1546 			}
1547 		}
1548 
1549 		if (++printed >= print_nr_entries)
1550 			break;
1551 	}
1552 
1553 	print_bad_events(bad, total);
1554 }
1555 
1556 static bool force;
1557 
1558 static int __cmd_report(bool display_info)
1559 {
1560 	int err = -EINVAL;
1561 	struct perf_tool eops = {
1562 		.attr		 = perf_event__process_attr,
1563 		.event_update	 = process_event_update,
1564 		.sample		 = process_sample_event,
1565 		.comm		 = perf_event__process_comm,
1566 		.mmap		 = perf_event__process_mmap,
1567 		.namespaces	 = perf_event__process_namespaces,
1568 		.tracing_data	 = perf_event__process_tracing_data,
1569 		.ordered_events	 = true,
1570 	};
1571 	struct perf_data data = {
1572 		.path  = input_name,
1573 		.mode  = PERF_DATA_MODE_READ,
1574 		.force = force,
1575 	};
1576 
1577 	session = perf_session__new(&data, &eops);
1578 	if (IS_ERR(session)) {
1579 		pr_err("Initializing perf session failed\n");
1580 		return PTR_ERR(session);
1581 	}
1582 
1583 	/* for lock function check */
1584 	symbol_conf.sort_by_name = true;
1585 	symbol__init(&session->header.env);
1586 
1587 	if (!data.is_pipe) {
1588 		if (!perf_session__has_traces(session, "lock record"))
1589 			goto out_delete;
1590 
1591 		if (perf_session__set_tracepoints_handlers(session, lock_tracepoints)) {
1592 			pr_err("Initializing perf session tracepoint handlers failed\n");
1593 			goto out_delete;
1594 		}
1595 
1596 		if (perf_session__set_tracepoints_handlers(session, contention_tracepoints)) {
1597 			pr_err("Initializing perf session tracepoint handlers failed\n");
1598 			goto out_delete;
1599 		}
1600 	}
1601 
1602 	if (setup_output_field(false, output_fields))
1603 		goto out_delete;
1604 
1605 	if (select_key(false))
1606 		goto out_delete;
1607 
1608 	if (show_thread_stats)
1609 		aggr_mode = LOCK_AGGR_TASK;
1610 
1611 	err = perf_session__process_events(session);
1612 	if (err)
1613 		goto out_delete;
1614 
1615 	setup_pager();
1616 	if (display_info) /* used for info subcommand */
1617 		err = dump_info();
1618 	else {
1619 		combine_result();
1620 		sort_result();
1621 		print_result();
1622 	}
1623 
1624 out_delete:
1625 	perf_session__delete(session);
1626 	return err;
1627 }
1628 
1629 static void sighandler(int sig __maybe_unused)
1630 {
1631 }
1632 
1633 static int __cmd_contention(int argc, const char **argv)
1634 {
1635 	int err = -EINVAL;
1636 	struct perf_tool eops = {
1637 		.attr		 = perf_event__process_attr,
1638 		.event_update	 = process_event_update,
1639 		.sample		 = process_sample_event,
1640 		.comm		 = perf_event__process_comm,
1641 		.mmap		 = perf_event__process_mmap,
1642 		.tracing_data	 = perf_event__process_tracing_data,
1643 		.ordered_events	 = true,
1644 	};
1645 	struct perf_data data = {
1646 		.path  = input_name,
1647 		.mode  = PERF_DATA_MODE_READ,
1648 		.force = force,
1649 	};
1650 	struct lock_contention con = {
1651 		.target = &target,
1652 		.result = &lockhash_table[0],
1653 		.map_nr_entries = bpf_map_entries,
1654 		.max_stack = max_stack_depth,
1655 		.stack_skip = stack_skip,
1656 	};
1657 
1658 	session = perf_session__new(use_bpf ? NULL : &data, &eops);
1659 	if (IS_ERR(session)) {
1660 		pr_err("Initializing perf session failed\n");
1661 		return PTR_ERR(session);
1662 	}
1663 
1664 	con.machine = &session->machines.host;
1665 
1666 	con.aggr_mode = aggr_mode = show_thread_stats ? LOCK_AGGR_TASK :
1667 		show_lock_addrs ? LOCK_AGGR_ADDR : LOCK_AGGR_CALLER;
1668 
1669 	/* for lock function check */
1670 	symbol_conf.sort_by_name = true;
1671 	symbol__init(&session->header.env);
1672 
1673 	if (use_bpf) {
1674 		err = target__validate(&target);
1675 		if (err) {
1676 			char errbuf[512];
1677 
1678 			target__strerror(&target, err, errbuf, 512);
1679 			pr_err("%s\n", errbuf);
1680 			goto out_delete;
1681 		}
1682 
1683 		signal(SIGINT, sighandler);
1684 		signal(SIGCHLD, sighandler);
1685 		signal(SIGTERM, sighandler);
1686 
1687 		con.evlist = evlist__new();
1688 		if (con.evlist == NULL) {
1689 			err = -ENOMEM;
1690 			goto out_delete;
1691 		}
1692 
1693 		err = evlist__create_maps(con.evlist, &target);
1694 		if (err < 0)
1695 			goto out_delete;
1696 
1697 		if (argc) {
1698 			err = evlist__prepare_workload(con.evlist, &target,
1699 						       argv, false, NULL);
1700 			if (err < 0)
1701 				goto out_delete;
1702 		}
1703 
1704 		if (lock_contention_prepare(&con) < 0) {
1705 			pr_err("lock contention BPF setup failed\n");
1706 			goto out_delete;
1707 		}
1708 	} else if (!data.is_pipe) {
1709 		if (!perf_session__has_traces(session, "lock record"))
1710 			goto out_delete;
1711 
1712 		if (!evlist__find_evsel_by_str(session->evlist,
1713 					       "lock:contention_begin")) {
1714 			pr_err("lock contention evsel not found\n");
1715 			goto out_delete;
1716 		}
1717 
1718 		if (perf_session__set_tracepoints_handlers(session,
1719 						contention_tracepoints)) {
1720 			pr_err("Initializing perf session tracepoint handlers failed\n");
1721 			goto out_delete;
1722 		}
1723 	}
1724 
1725 	if (setup_output_field(true, output_fields))
1726 		goto out_delete;
1727 
1728 	if (select_key(true))
1729 		goto out_delete;
1730 
1731 	if (use_bpf) {
1732 		lock_contention_start();
1733 		if (argc)
1734 			evlist__start_workload(con.evlist);
1735 
1736 		/* wait for signal */
1737 		pause();
1738 
1739 		lock_contention_stop();
1740 		lock_contention_read(&con);
1741 
1742 		/* abuse bad hist stats for lost entries */
1743 		bad_hist[BROKEN_CONTENDED] = con.lost;
1744 	} else {
1745 		err = perf_session__process_events(session);
1746 		if (err)
1747 			goto out_delete;
1748 	}
1749 
1750 	setup_pager();
1751 
1752 	sort_contention_result();
1753 	print_contention_result(&con);
1754 
1755 out_delete:
1756 	evlist__delete(con.evlist);
1757 	lock_contention_finish();
1758 	perf_session__delete(session);
1759 	return err;
1760 }
1761 
1762 
1763 static int __cmd_record(int argc, const char **argv)
1764 {
1765 	const char *record_args[] = {
1766 		"record", "-R", "-m", "1024", "-c", "1", "--synth", "task",
1767 	};
1768 	const char *callgraph_args[] = {
1769 		"--call-graph", "fp," __stringify(CONTENTION_STACK_DEPTH),
1770 	};
1771 	unsigned int rec_argc, i, j, ret;
1772 	unsigned int nr_tracepoints;
1773 	unsigned int nr_callgraph_args = 0;
1774 	const char **rec_argv;
1775 	bool has_lock_stat = true;
1776 
1777 	for (i = 0; i < ARRAY_SIZE(lock_tracepoints); i++) {
1778 		if (!is_valid_tracepoint(lock_tracepoints[i].name)) {
1779 			pr_debug("tracepoint %s is not enabled. "
1780 				 "Are CONFIG_LOCKDEP and CONFIG_LOCK_STAT enabled?\n",
1781 				 lock_tracepoints[i].name);
1782 			has_lock_stat = false;
1783 			break;
1784 		}
1785 	}
1786 
1787 	if (has_lock_stat)
1788 		goto setup_args;
1789 
1790 	for (i = 0; i < ARRAY_SIZE(contention_tracepoints); i++) {
1791 		if (!is_valid_tracepoint(contention_tracepoints[i].name)) {
1792 			pr_err("tracepoint %s is not enabled.\n",
1793 			       contention_tracepoints[i].name);
1794 			return 1;
1795 		}
1796 	}
1797 
1798 	nr_callgraph_args = ARRAY_SIZE(callgraph_args);
1799 
1800 setup_args:
1801 	rec_argc = ARRAY_SIZE(record_args) + nr_callgraph_args + argc - 1;
1802 
1803 	if (has_lock_stat)
1804 		nr_tracepoints = ARRAY_SIZE(lock_tracepoints);
1805 	else
1806 		nr_tracepoints = ARRAY_SIZE(contention_tracepoints);
1807 
1808 	/* factor of 2 is for -e in front of each tracepoint */
1809 	rec_argc += 2 * nr_tracepoints;
1810 
1811 	rec_argv = calloc(rec_argc + 1, sizeof(char *));
1812 	if (!rec_argv)
1813 		return -ENOMEM;
1814 
1815 	for (i = 0; i < ARRAY_SIZE(record_args); i++)
1816 		rec_argv[i] = strdup(record_args[i]);
1817 
1818 	for (j = 0; j < nr_tracepoints; j++) {
1819 		const char *ev_name;
1820 
1821 		if (has_lock_stat)
1822 			ev_name = strdup(lock_tracepoints[j].name);
1823 		else
1824 			ev_name = strdup(contention_tracepoints[j].name);
1825 
1826 		if (!ev_name)
1827 			return -ENOMEM;
1828 
1829 		rec_argv[i++] = "-e";
1830 		rec_argv[i++] = ev_name;
1831 	}
1832 
1833 	for (j = 0; j < nr_callgraph_args; j++, i++)
1834 		rec_argv[i] = callgraph_args[j];
1835 
1836 	for (j = 1; j < (unsigned int)argc; j++, i++)
1837 		rec_argv[i] = argv[j];
1838 
1839 	BUG_ON(i != rec_argc);
1840 
1841 	ret = cmd_record(i, rec_argv);
1842 	free(rec_argv);
1843 	return ret;
1844 }
1845 
1846 static int parse_map_entry(const struct option *opt, const char *str,
1847 			    int unset __maybe_unused)
1848 {
1849 	unsigned long *len = (unsigned long *)opt->value;
1850 	unsigned long val;
1851 	char *endptr;
1852 
1853 	errno = 0;
1854 	val = strtoul(str, &endptr, 0);
1855 	if (*endptr != '\0' || errno != 0) {
1856 		pr_err("invalid BPF map length: %s\n", str);
1857 		return -1;
1858 	}
1859 
1860 	*len = val;
1861 	return 0;
1862 }
1863 
1864 static int parse_max_stack(const struct option *opt, const char *str,
1865 			   int unset __maybe_unused)
1866 {
1867 	unsigned long *len = (unsigned long *)opt->value;
1868 	long val;
1869 	char *endptr;
1870 
1871 	errno = 0;
1872 	val = strtol(str, &endptr, 0);
1873 	if (*endptr != '\0' || errno != 0) {
1874 		pr_err("invalid max stack depth: %s\n", str);
1875 		return -1;
1876 	}
1877 
1878 	if (val < 0 || val > sysctl__max_stack()) {
1879 		pr_err("invalid max stack depth: %ld\n", val);
1880 		return -1;
1881 	}
1882 
1883 	*len = val;
1884 	return 0;
1885 }
1886 
1887 int cmd_lock(int argc, const char **argv)
1888 {
1889 	const struct option lock_options[] = {
1890 	OPT_STRING('i', "input", &input_name, "file", "input file name"),
1891 	OPT_INCR('v', "verbose", &verbose, "be more verbose (show symbol address, etc)"),
1892 	OPT_BOOLEAN('D', "dump-raw-trace", &dump_trace, "dump raw trace in ASCII"),
1893 	OPT_BOOLEAN('f', "force", &force, "don't complain, do it"),
1894 	OPT_STRING(0, "vmlinux", &symbol_conf.vmlinux_name,
1895 		   "file", "vmlinux pathname"),
1896 	OPT_STRING(0, "kallsyms", &symbol_conf.kallsyms_name,
1897 		   "file", "kallsyms pathname"),
1898 	OPT_BOOLEAN('q', "quiet", &quiet, "Do not show any warnings or messages"),
1899 	OPT_END()
1900 	};
1901 
1902 	const struct option info_options[] = {
1903 	OPT_BOOLEAN('t', "threads", &info_threads,
1904 		    "dump thread list in perf.data"),
1905 	OPT_BOOLEAN('m', "map", &info_map,
1906 		    "map of lock instances (address:name table)"),
1907 	OPT_PARENT(lock_options)
1908 	};
1909 
1910 	const struct option report_options[] = {
1911 	OPT_STRING('k', "key", &sort_key, "acquired",
1912 		    "key for sorting (acquired / contended / avg_wait / wait_total / wait_max / wait_min)"),
1913 	OPT_STRING('F', "field", &output_fields, NULL,
1914 		    "output fields (acquired / contended / avg_wait / wait_total / wait_max / wait_min)"),
1915 	/* TODO: type */
1916 	OPT_BOOLEAN('c', "combine-locks", &combine_locks,
1917 		    "combine locks in the same class"),
1918 	OPT_BOOLEAN('t', "threads", &show_thread_stats,
1919 		    "show per-thread lock stats"),
1920 	OPT_INTEGER('E', "entries", &print_nr_entries, "display this many functions"),
1921 	OPT_PARENT(lock_options)
1922 	};
1923 
1924 	struct option contention_options[] = {
1925 	OPT_STRING('k', "key", &sort_key, "wait_total",
1926 		    "key for sorting (contended / wait_total / wait_max / wait_min / avg_wait)"),
1927 	OPT_STRING('F', "field", &output_fields, "contended,wait_total,wait_max,avg_wait",
1928 		    "output fields (contended / wait_total / wait_max / wait_min / avg_wait)"),
1929 	OPT_BOOLEAN('t', "threads", &show_thread_stats,
1930 		    "show per-thread lock stats"),
1931 	OPT_BOOLEAN('b', "use-bpf", &use_bpf, "use BPF program to collect lock contention stats"),
1932 	OPT_BOOLEAN('a', "all-cpus", &target.system_wide,
1933 		    "System-wide collection from all CPUs"),
1934 	OPT_STRING('C', "cpu", &target.cpu_list, "cpu",
1935 		    "List of cpus to monitor"),
1936 	OPT_STRING('p', "pid", &target.pid, "pid",
1937 		   "Trace on existing process id"),
1938 	OPT_STRING(0, "tid", &target.tid, "tid",
1939 		   "Trace on existing thread id (exclusive to --pid)"),
1940 	OPT_CALLBACK(0, "map-nr-entries", &bpf_map_entries, "num",
1941 		     "Max number of BPF map entries", parse_map_entry),
1942 	OPT_CALLBACK(0, "max-stack", &max_stack_depth, "num",
1943 		     "Set the maximum stack depth when collecting lopck contention, "
1944 		     "Default: " __stringify(CONTENTION_STACK_DEPTH), parse_max_stack),
1945 	OPT_INTEGER(0, "stack-skip", &stack_skip,
1946 		    "Set the number of stack depth to skip when finding a lock caller, "
1947 		    "Default: " __stringify(CONTENTION_STACK_SKIP)),
1948 	OPT_INTEGER('E', "entries", &print_nr_entries, "display this many functions"),
1949 	OPT_BOOLEAN('l', "lock-addr", &show_lock_addrs, "show lock stats by address"),
1950 	OPT_PARENT(lock_options)
1951 	};
1952 
1953 	const char * const info_usage[] = {
1954 		"perf lock info [<options>]",
1955 		NULL
1956 	};
1957 	const char *const lock_subcommands[] = { "record", "report", "script",
1958 						 "info", "contention", NULL };
1959 	const char *lock_usage[] = {
1960 		NULL,
1961 		NULL
1962 	};
1963 	const char * const report_usage[] = {
1964 		"perf lock report [<options>]",
1965 		NULL
1966 	};
1967 	const char * const contention_usage[] = {
1968 		"perf lock contention [<options>]",
1969 		NULL
1970 	};
1971 	unsigned int i;
1972 	int rc = 0;
1973 
1974 	for (i = 0; i < LOCKHASH_SIZE; i++)
1975 		INIT_HLIST_HEAD(lockhash_table + i);
1976 
1977 	argc = parse_options_subcommand(argc, argv, lock_options, lock_subcommands,
1978 					lock_usage, PARSE_OPT_STOP_AT_NON_OPTION);
1979 	if (!argc)
1980 		usage_with_options(lock_usage, lock_options);
1981 
1982 	if (strlen(argv[0]) > 2 && strstarts("record", argv[0])) {
1983 		return __cmd_record(argc, argv);
1984 	} else if (strlen(argv[0]) > 2 && strstarts("report", argv[0])) {
1985 		trace_handler = &report_lock_ops;
1986 		if (argc) {
1987 			argc = parse_options(argc, argv,
1988 					     report_options, report_usage, 0);
1989 			if (argc)
1990 				usage_with_options(report_usage, report_options);
1991 		}
1992 		rc = __cmd_report(false);
1993 	} else if (!strcmp(argv[0], "script")) {
1994 		/* Aliased to 'perf script' */
1995 		return cmd_script(argc, argv);
1996 	} else if (!strcmp(argv[0], "info")) {
1997 		if (argc) {
1998 			argc = parse_options(argc, argv,
1999 					     info_options, info_usage, 0);
2000 			if (argc)
2001 				usage_with_options(info_usage, info_options);
2002 		}
2003 		/* recycling report_lock_ops */
2004 		trace_handler = &report_lock_ops;
2005 		rc = __cmd_report(true);
2006 	} else if (strlen(argv[0]) > 2 && strstarts("contention", argv[0])) {
2007 		trace_handler = &contention_lock_ops;
2008 		sort_key = "wait_total";
2009 		output_fields = "contended,wait_total,wait_max,avg_wait";
2010 
2011 #ifndef HAVE_BPF_SKEL
2012 		set_option_nobuild(contention_options, 'b', "use-bpf",
2013 				   "no BUILD_BPF_SKEL=1", false);
2014 #endif
2015 		if (argc) {
2016 			argc = parse_options(argc, argv, contention_options,
2017 					     contention_usage, 0);
2018 		}
2019 
2020 		if (show_thread_stats && show_lock_addrs) {
2021 			pr_err("Cannot use thread and addr mode together\n");
2022 			parse_options_usage(contention_usage, contention_options,
2023 					    "threads", 0);
2024 			parse_options_usage(NULL, contention_options,
2025 					    "lock-addr", 0);
2026 			return -1;
2027 		}
2028 
2029 		rc = __cmd_contention(argc, argv);
2030 	} else {
2031 		usage_with_options(lock_usage, lock_options);
2032 	}
2033 
2034 	return rc;
2035 }
2036