1 // SPDX-License-Identifier: GPL-2.0
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"
13 #include <subcmd/pager.h>
14 #include <subcmd/parse-options.h>
15 #include "util/trace-event.h"
17 #include "util/debug.h"
18 #include "util/session.h"
19 #include "util/tool.h"
20 #include "util/data.h"
22 #include <sys/types.h>
23 #include <sys/prctl.h>
24 #include <semaphore.h>
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>
35 static struct perf_session *session;
37 /* based on kernel/lockdep.c */
38 #define LOCKHASH_BITS 12
39 #define LOCKHASH_SIZE (1UL << LOCKHASH_BITS)
41 static struct list_head lockhash_table[LOCKHASH_SIZE];
43 #define __lockhashfn(key) hash_long((unsigned long)key, LOCKHASH_BITS)
44 #define lockhashentry(key) (lockhash_table + __lockhashfn((key)))
47 struct list_head hash_entry;
48 struct rb_node rb; /* used for sorting */
51 * FIXME: evsel__intval() returns u64,
52 * so address of lockdep_map should be treated as 64bit.
53 * Is there more better solution?
55 void *addr; /* address of lockdep_map, used as ID */
56 char *name; /* for strcpy(), we cannot use const */
58 unsigned int nr_acquire;
59 unsigned int nr_acquired;
60 unsigned int nr_contended;
61 unsigned int nr_release;
63 unsigned int nr_readlock;
64 unsigned int nr_trylock;
66 /* these times are in nano sec. */
72 int discard; /* flag of blacklist */
76 * States of lock_seq_stat
78 * UNINITIALIZED is required for detecting first event of acquire.
79 * As the nature of lock events, there is no guarantee
80 * that the first event for the locks are acquire,
81 * it can be acquired, contended or release.
83 #define SEQ_STATE_UNINITIALIZED 0 /* initial state */
84 #define SEQ_STATE_RELEASED 1
85 #define SEQ_STATE_ACQUIRING 2
86 #define SEQ_STATE_ACQUIRED 3
87 #define SEQ_STATE_READ_ACQUIRED 4
88 #define SEQ_STATE_CONTENDED 5
92 * Imported from include/linux/sched.h.
93 * Should this be synchronized?
95 #define MAX_LOCK_DEPTH 48
98 * struct lock_seq_stat:
99 * Place to put on state of one lock sequence
100 * 1) acquire -> acquired -> release
101 * 2) acquire -> contended -> acquired -> release
102 * 3) acquire (with read or try) -> release
103 * 4) Are there other patterns?
105 struct lock_seq_stat {
106 struct list_head list;
118 struct list_head seq_list;
121 static struct rb_root thread_stats;
123 static struct thread_stat *thread_stat_find(u32 tid)
125 struct rb_node *node;
126 struct thread_stat *st;
128 node = thread_stats.rb_node;
130 st = container_of(node, struct thread_stat, rb);
133 else if (tid < st->tid)
134 node = node->rb_left;
136 node = node->rb_right;
142 static void thread_stat_insert(struct thread_stat *new)
144 struct rb_node **rb = &thread_stats.rb_node;
145 struct rb_node *parent = NULL;
146 struct thread_stat *p;
149 p = container_of(*rb, struct thread_stat, rb);
152 if (new->tid < p->tid)
153 rb = &(*rb)->rb_left;
154 else if (new->tid > p->tid)
155 rb = &(*rb)->rb_right;
157 BUG_ON("inserting invalid thread_stat\n");
160 rb_link_node(&new->rb, parent, rb);
161 rb_insert_color(&new->rb, &thread_stats);
164 static struct thread_stat *thread_stat_findnew_after_first(u32 tid)
166 struct thread_stat *st;
168 st = thread_stat_find(tid);
172 st = zalloc(sizeof(struct thread_stat));
174 pr_err("memory allocation failed\n");
179 INIT_LIST_HEAD(&st->seq_list);
181 thread_stat_insert(st);
186 static struct thread_stat *thread_stat_findnew_first(u32 tid);
187 static struct thread_stat *(*thread_stat_findnew)(u32 tid) =
188 thread_stat_findnew_first;
190 static struct thread_stat *thread_stat_findnew_first(u32 tid)
192 struct thread_stat *st;
194 st = zalloc(sizeof(struct thread_stat));
196 pr_err("memory allocation failed\n");
200 INIT_LIST_HEAD(&st->seq_list);
202 rb_link_node(&st->rb, NULL, &thread_stats.rb_node);
203 rb_insert_color(&st->rb, &thread_stats);
205 thread_stat_findnew = thread_stat_findnew_after_first;
209 /* build simple key function one is bigger than two */
210 #define SINGLE_KEY(member) \
211 static int lock_stat_key_ ## member(struct lock_stat *one, \
212 struct lock_stat *two) \
214 return one->member > two->member; \
217 SINGLE_KEY(nr_acquired)
218 SINGLE_KEY(nr_contended)
219 SINGLE_KEY(avg_wait_time)
220 SINGLE_KEY(wait_time_total)
221 SINGLE_KEY(wait_time_max)
223 static int lock_stat_key_wait_time_min(struct lock_stat *one,
224 struct lock_stat *two)
226 u64 s1 = one->wait_time_min;
227 u64 s2 = two->wait_time_min;
228 if (s1 == ULLONG_MAX)
230 if (s2 == ULLONG_MAX)
237 * name: the value for specify by user
238 * this should be simpler than raw name of member
239 * e.g. nr_acquired -> acquired, wait_time_total -> wait_total
242 int (*key)(struct lock_stat*, struct lock_stat*);
245 static const char *sort_key = "acquired";
247 static int (*compare)(struct lock_stat *, struct lock_stat *);
249 static struct rb_root result; /* place to store sorted data */
251 #define DEF_KEY_LOCK(name, fn_suffix) \
252 { #name, lock_stat_key_ ## fn_suffix }
253 struct lock_key keys[] = {
254 DEF_KEY_LOCK(acquired, nr_acquired),
255 DEF_KEY_LOCK(contended, nr_contended),
256 DEF_KEY_LOCK(avg_wait, avg_wait_time),
257 DEF_KEY_LOCK(wait_total, wait_time_total),
258 DEF_KEY_LOCK(wait_min, wait_time_min),
259 DEF_KEY_LOCK(wait_max, wait_time_max),
261 /* extra comparisons much complicated should be here */
266 static int select_key(void)
270 for (i = 0; keys[i].name; i++) {
271 if (!strcmp(keys[i].name, sort_key)) {
272 compare = keys[i].key;
277 pr_err("Unknown compare key: %s\n", sort_key);
282 static void insert_to_result(struct lock_stat *st,
283 int (*bigger)(struct lock_stat *, struct lock_stat *))
285 struct rb_node **rb = &result.rb_node;
286 struct rb_node *parent = NULL;
290 p = container_of(*rb, struct lock_stat, rb);
294 rb = &(*rb)->rb_left;
296 rb = &(*rb)->rb_right;
299 rb_link_node(&st->rb, parent, rb);
300 rb_insert_color(&st->rb, &result);
303 /* returns left most element of result, and erase it */
304 static struct lock_stat *pop_from_result(void)
306 struct rb_node *node = result.rb_node;
311 while (node->rb_left)
312 node = node->rb_left;
314 rb_erase(node, &result);
315 return container_of(node, struct lock_stat, rb);
318 static struct lock_stat *lock_stat_findnew(void *addr, const char *name)
320 struct list_head *entry = lockhashentry(addr);
321 struct lock_stat *ret, *new;
323 list_for_each_entry(ret, entry, hash_entry) {
324 if (ret->addr == addr)
328 new = zalloc(sizeof(struct lock_stat));
333 new->name = zalloc(sizeof(char) * strlen(name) + 1);
339 strcpy(new->name, name);
340 new->wait_time_min = ULLONG_MAX;
342 list_add(&new->hash_entry, entry);
346 pr_err("memory allocation failed\n");
350 struct trace_lock_handler {
351 int (*acquire_event)(struct evsel *evsel,
352 struct perf_sample *sample);
354 int (*acquired_event)(struct evsel *evsel,
355 struct perf_sample *sample);
357 int (*contended_event)(struct evsel *evsel,
358 struct perf_sample *sample);
360 int (*release_event)(struct evsel *evsel,
361 struct perf_sample *sample);
364 static struct lock_seq_stat *get_seq(struct thread_stat *ts, void *addr)
366 struct lock_seq_stat *seq;
368 list_for_each_entry(seq, &ts->seq_list, list) {
369 if (seq->addr == addr)
373 seq = zalloc(sizeof(struct lock_seq_stat));
375 pr_err("memory allocation failed\n");
378 seq->state = SEQ_STATE_UNINITIALIZED;
381 list_add(&seq->list, &ts->seq_list);
393 static int bad_hist[BROKEN_MAX];
400 static int report_lock_acquire_event(struct evsel *evsel,
401 struct perf_sample *sample)
404 struct lock_stat *ls;
405 struct thread_stat *ts;
406 struct lock_seq_stat *seq;
407 const char *name = evsel__strval(evsel, sample, "name");
408 u64 tmp = evsel__intval(evsel, sample, "lockdep_addr");
409 int flag = evsel__intval(evsel, sample, "flags");
411 memcpy(&addr, &tmp, sizeof(void *));
413 ls = lock_stat_findnew(addr, name);
419 ts = thread_stat_findnew(sample->tid);
423 seq = get_seq(ts, addr);
427 switch (seq->state) {
428 case SEQ_STATE_UNINITIALIZED:
429 case SEQ_STATE_RELEASED:
431 seq->state = SEQ_STATE_ACQUIRING;
435 if (flag & READ_LOCK)
437 seq->state = SEQ_STATE_READ_ACQUIRED;
442 case SEQ_STATE_READ_ACQUIRED:
443 if (flag & READ_LOCK) {
451 case SEQ_STATE_ACQUIRED:
452 case SEQ_STATE_ACQUIRING:
453 case SEQ_STATE_CONTENDED:
455 /* broken lock sequence, discard it */
457 bad_hist[BROKEN_ACQUIRE]++;
458 list_del_init(&seq->list);
462 BUG_ON("Unknown state of lock sequence found!\n");
467 seq->prev_event_time = sample->time;
472 static int report_lock_acquired_event(struct evsel *evsel,
473 struct perf_sample *sample)
476 struct lock_stat *ls;
477 struct thread_stat *ts;
478 struct lock_seq_stat *seq;
480 const char *name = evsel__strval(evsel, sample, "name");
481 u64 tmp = evsel__intval(evsel, sample, "lockdep_addr");
483 memcpy(&addr, &tmp, sizeof(void *));
485 ls = lock_stat_findnew(addr, name);
491 ts = thread_stat_findnew(sample->tid);
495 seq = get_seq(ts, addr);
499 switch (seq->state) {
500 case SEQ_STATE_UNINITIALIZED:
501 /* orphan event, do nothing */
503 case SEQ_STATE_ACQUIRING:
505 case SEQ_STATE_CONTENDED:
506 contended_term = sample->time - seq->prev_event_time;
507 ls->wait_time_total += contended_term;
508 if (contended_term < ls->wait_time_min)
509 ls->wait_time_min = contended_term;
510 if (ls->wait_time_max < contended_term)
511 ls->wait_time_max = contended_term;
513 case SEQ_STATE_RELEASED:
514 case SEQ_STATE_ACQUIRED:
515 case SEQ_STATE_READ_ACQUIRED:
516 /* broken lock sequence, discard it */
518 bad_hist[BROKEN_ACQUIRED]++;
519 list_del_init(&seq->list);
523 BUG_ON("Unknown state of lock sequence found!\n");
527 seq->state = SEQ_STATE_ACQUIRED;
529 ls->avg_wait_time = ls->nr_contended ? ls->wait_time_total/ls->nr_contended : 0;
530 seq->prev_event_time = sample->time;
535 static int report_lock_contended_event(struct evsel *evsel,
536 struct perf_sample *sample)
539 struct lock_stat *ls;
540 struct thread_stat *ts;
541 struct lock_seq_stat *seq;
542 const char *name = evsel__strval(evsel, sample, "name");
543 u64 tmp = evsel__intval(evsel, sample, "lockdep_addr");
545 memcpy(&addr, &tmp, sizeof(void *));
547 ls = lock_stat_findnew(addr, name);
553 ts = thread_stat_findnew(sample->tid);
557 seq = get_seq(ts, addr);
561 switch (seq->state) {
562 case SEQ_STATE_UNINITIALIZED:
563 /* orphan event, do nothing */
565 case SEQ_STATE_ACQUIRING:
567 case SEQ_STATE_RELEASED:
568 case SEQ_STATE_ACQUIRED:
569 case SEQ_STATE_READ_ACQUIRED:
570 case SEQ_STATE_CONTENDED:
571 /* broken lock sequence, discard it */
573 bad_hist[BROKEN_CONTENDED]++;
574 list_del_init(&seq->list);
578 BUG_ON("Unknown state of lock sequence found!\n");
582 seq->state = SEQ_STATE_CONTENDED;
584 ls->avg_wait_time = ls->wait_time_total/ls->nr_contended;
585 seq->prev_event_time = sample->time;
590 static int report_lock_release_event(struct evsel *evsel,
591 struct perf_sample *sample)
594 struct lock_stat *ls;
595 struct thread_stat *ts;
596 struct lock_seq_stat *seq;
597 const char *name = evsel__strval(evsel, sample, "name");
598 u64 tmp = evsel__intval(evsel, sample, "lockdep_addr");
600 memcpy(&addr, &tmp, sizeof(void *));
602 ls = lock_stat_findnew(addr, name);
608 ts = thread_stat_findnew(sample->tid);
612 seq = get_seq(ts, addr);
616 switch (seq->state) {
617 case SEQ_STATE_UNINITIALIZED:
619 case SEQ_STATE_ACQUIRED:
621 case SEQ_STATE_READ_ACQUIRED:
623 BUG_ON(seq->read_count < 0);
624 if (seq->read_count) {
629 case SEQ_STATE_ACQUIRING:
630 case SEQ_STATE_CONTENDED:
631 case SEQ_STATE_RELEASED:
632 /* broken lock sequence, discard it */
634 bad_hist[BROKEN_RELEASE]++;
637 BUG_ON("Unknown state of lock sequence found!\n");
643 list_del_init(&seq->list);
649 /* lock oriented handlers */
650 /* TODO: handlers for CPU oriented, thread oriented */
651 static struct trace_lock_handler report_lock_ops = {
652 .acquire_event = report_lock_acquire_event,
653 .acquired_event = report_lock_acquired_event,
654 .contended_event = report_lock_contended_event,
655 .release_event = report_lock_release_event,
658 static struct trace_lock_handler *trace_handler;
660 static int evsel__process_lock_acquire(struct evsel *evsel, struct perf_sample *sample)
662 if (trace_handler->acquire_event)
663 return trace_handler->acquire_event(evsel, sample);
667 static int evsel__process_lock_acquired(struct evsel *evsel, struct perf_sample *sample)
669 if (trace_handler->acquired_event)
670 return trace_handler->acquired_event(evsel, sample);
674 static int evsel__process_lock_contended(struct evsel *evsel, struct perf_sample *sample)
676 if (trace_handler->contended_event)
677 return trace_handler->contended_event(evsel, sample);
681 static int evsel__process_lock_release(struct evsel *evsel, struct perf_sample *sample)
683 if (trace_handler->release_event)
684 return trace_handler->release_event(evsel, sample);
688 static void print_bad_events(int bad, int total)
690 /* Output for debug, this have to be removed */
692 const char *name[4] =
693 { "acquire", "acquired", "contended", "release" };
695 pr_info("\n=== output for debug===\n\n");
696 pr_info("bad: %d, total: %d\n", bad, total);
697 pr_info("bad rate: %.2f %%\n", (double)bad / (double)total * 100);
698 pr_info("histogram of events caused bad sequence\n");
699 for (i = 0; i < BROKEN_MAX; i++)
700 pr_info(" %10s: %d\n", name[i], bad_hist[i]);
703 /* TODO: various way to print, coloring, nano or milli sec */
704 static void print_result(void)
706 struct lock_stat *st;
710 pr_info("%20s ", "Name");
711 pr_info("%10s ", "acquired");
712 pr_info("%10s ", "contended");
714 pr_info("%15s ", "avg wait (ns)");
715 pr_info("%15s ", "total wait (ns)");
716 pr_info("%15s ", "max wait (ns)");
717 pr_info("%15s ", "min wait (ns)");
722 while ((st = pop_from_result())) {
730 if (strlen(st->name) < 16) {
731 /* output raw name */
732 pr_info("%20s ", st->name);
734 strncpy(cut_name, st->name, 16);
739 /* cut off name for saving output style */
740 pr_info("%20s ", cut_name);
743 pr_info("%10u ", st->nr_acquired);
744 pr_info("%10u ", st->nr_contended);
746 pr_info("%15" PRIu64 " ", st->avg_wait_time);
747 pr_info("%15" PRIu64 " ", st->wait_time_total);
748 pr_info("%15" PRIu64 " ", st->wait_time_max);
749 pr_info("%15" PRIu64 " ", st->wait_time_min == ULLONG_MAX ?
750 0 : st->wait_time_min);
754 print_bad_events(bad, total);
757 static bool info_threads, info_map;
759 static void dump_threads(void)
761 struct thread_stat *st;
762 struct rb_node *node;
765 pr_info("%10s: comm\n", "Thread ID");
767 node = rb_first(&thread_stats);
769 st = container_of(node, struct thread_stat, rb);
770 t = perf_session__findnew(session, st->tid);
771 pr_info("%10d: %s\n", st->tid, thread__comm_str(t));
772 node = rb_next(node);
777 static void dump_map(void)
780 struct lock_stat *st;
782 pr_info("Address of instance: name of class\n");
783 for (i = 0; i < LOCKHASH_SIZE; i++) {
784 list_for_each_entry(st, &lockhash_table[i], hash_entry) {
785 pr_info(" %p: %s\n", st->addr, st->name);
790 static int dump_info(void)
800 pr_err("Unknown type of information\n");
806 typedef int (*tracepoint_handler)(struct evsel *evsel,
807 struct perf_sample *sample);
809 static int process_sample_event(struct perf_tool *tool __maybe_unused,
810 union perf_event *event,
811 struct perf_sample *sample,
813 struct machine *machine)
816 struct thread *thread = machine__findnew_thread(machine, sample->pid,
819 if (thread == NULL) {
820 pr_debug("problem processing %d event, skipping it.\n",
825 if (evsel->handler != NULL) {
826 tracepoint_handler f = evsel->handler;
827 err = f(evsel, sample);
835 static void sort_result(void)
838 struct lock_stat *st;
840 for (i = 0; i < LOCKHASH_SIZE; i++) {
841 list_for_each_entry(st, &lockhash_table[i], hash_entry) {
842 insert_to_result(st, compare);
847 static const struct evsel_str_handler lock_tracepoints[] = {
848 { "lock:lock_acquire", evsel__process_lock_acquire, }, /* CONFIG_LOCKDEP */
849 { "lock:lock_acquired", evsel__process_lock_acquired, }, /* CONFIG_LOCKDEP, CONFIG_LOCK_STAT */
850 { "lock:lock_contended", evsel__process_lock_contended, }, /* CONFIG_LOCKDEP, CONFIG_LOCK_STAT */
851 { "lock:lock_release", evsel__process_lock_release, }, /* CONFIG_LOCKDEP */
856 static int __cmd_report(bool display_info)
859 struct perf_tool eops = {
860 .sample = process_sample_event,
861 .comm = perf_event__process_comm,
862 .namespaces = perf_event__process_namespaces,
863 .ordered_events = true,
865 struct perf_data data = {
867 .mode = PERF_DATA_MODE_READ,
871 session = perf_session__new(&data, false, &eops);
872 if (IS_ERR(session)) {
873 pr_err("Initializing perf session failed\n");
874 return PTR_ERR(session);
877 symbol__init(&session->header.env);
879 if (!perf_session__has_traces(session, "lock record"))
882 if (perf_session__set_tracepoints_handlers(session, lock_tracepoints)) {
883 pr_err("Initializing perf session tracepoint handlers failed\n");
890 err = perf_session__process_events(session);
895 if (display_info) /* used for info subcommand */
903 perf_session__delete(session);
907 static int __cmd_record(int argc, const char **argv)
909 const char *record_args[] = {
910 "record", "-R", "-m", "1024", "-c", "1",
912 unsigned int rec_argc, i, j, ret;
913 const char **rec_argv;
915 for (i = 0; i < ARRAY_SIZE(lock_tracepoints); i++) {
916 if (!is_valid_tracepoint(lock_tracepoints[i].name)) {
917 pr_err("tracepoint %s is not enabled. "
918 "Are CONFIG_LOCKDEP and CONFIG_LOCK_STAT enabled?\n",
919 lock_tracepoints[i].name);
924 rec_argc = ARRAY_SIZE(record_args) + argc - 1;
925 /* factor of 2 is for -e in front of each tracepoint */
926 rec_argc += 2 * ARRAY_SIZE(lock_tracepoints);
928 rec_argv = calloc(rec_argc + 1, sizeof(char *));
932 for (i = 0; i < ARRAY_SIZE(record_args); i++)
933 rec_argv[i] = strdup(record_args[i]);
935 for (j = 0; j < ARRAY_SIZE(lock_tracepoints); j++) {
936 rec_argv[i++] = "-e";
937 rec_argv[i++] = strdup(lock_tracepoints[j].name);
940 for (j = 1; j < (unsigned int)argc; j++, i++)
941 rec_argv[i] = argv[j];
943 BUG_ON(i != rec_argc);
945 ret = cmd_record(i, rec_argv);
950 int cmd_lock(int argc, const char **argv)
952 const struct option lock_options[] = {
953 OPT_STRING('i', "input", &input_name, "file", "input file name"),
954 OPT_INCR('v', "verbose", &verbose, "be more verbose (show symbol address, etc)"),
955 OPT_BOOLEAN('D', "dump-raw-trace", &dump_trace, "dump raw trace in ASCII"),
956 OPT_BOOLEAN('f', "force", &force, "don't complain, do it"),
960 const struct option info_options[] = {
961 OPT_BOOLEAN('t', "threads", &info_threads,
962 "dump thread list in perf.data"),
963 OPT_BOOLEAN('m', "map", &info_map,
964 "map of lock instances (address:name table)"),
965 OPT_PARENT(lock_options)
968 const struct option report_options[] = {
969 OPT_STRING('k', "key", &sort_key, "acquired",
970 "key for sorting (acquired / contended / avg_wait / wait_total / wait_max / wait_min)"),
972 OPT_PARENT(lock_options)
975 const char * const info_usage[] = {
976 "perf lock info [<options>]",
979 const char *const lock_subcommands[] = { "record", "report", "script",
981 const char *lock_usage[] = {
985 const char * const report_usage[] = {
986 "perf lock report [<options>]",
992 for (i = 0; i < LOCKHASH_SIZE; i++)
993 INIT_LIST_HEAD(lockhash_table + i);
995 argc = parse_options_subcommand(argc, argv, lock_options, lock_subcommands,
996 lock_usage, PARSE_OPT_STOP_AT_NON_OPTION);
998 usage_with_options(lock_usage, lock_options);
1000 if (!strncmp(argv[0], "rec", 3)) {
1001 return __cmd_record(argc, argv);
1002 } else if (!strncmp(argv[0], "report", 6)) {
1003 trace_handler = &report_lock_ops;
1005 argc = parse_options(argc, argv,
1006 report_options, report_usage, 0);
1008 usage_with_options(report_usage, report_options);
1010 rc = __cmd_report(false);
1011 } else if (!strcmp(argv[0], "script")) {
1012 /* Aliased to 'perf script' */
1013 return cmd_script(argc, argv);
1014 } else if (!strcmp(argv[0], "info")) {
1016 argc = parse_options(argc, argv,
1017 info_options, info_usage, 0);
1019 usage_with_options(info_usage, info_options);
1021 /* recycling report_lock_ops */
1022 trace_handler = &report_lock_ops;
1023 rc = __cmd_report(true);
1025 usage_with_options(lock_usage, lock_options);