From b4a7eff93c39f985b33ac114f83ac5b325f42151 Mon Sep 17 00:00:00 2001 From: Namhyung Kim Date: Mon, 19 Dec 2022 12:17:28 -0800 Subject: [PATCH] perf lock contention: Add -Y/--type-filter option The -Y/--type-filter option is to filter the result for specific lock types only. It can accept comma-separated values. Note that it would accept type names like one in the output. spinlock, mutex, rwsem:R and so on. For RW-variant lock types, it converts the name to the both variants. In other words, "rwsem" is same as "rwsem:R,rwsem:W". Also note that "mutex" has two different encoding - one for sleeping wait, another for optimistic spinning. Add "mutex-spin" entry for the lock_type_table so that we can add it for "mutex" under the table. $ sudo ./perf lock record -a -- ./perf bench sched messaging $ sudo ./perf lock con -E 5 -Y spinlock contended total wait max wait avg wait type caller 802 1.26 ms 11.73 us 1.58 us spinlock __wake_up_common_lock+0x62 13 787.16 us 105.44 us 60.55 us spinlock remove_wait_queue+0x14 12 612.96 us 78.70 us 51.08 us spinlock prepare_to_wait+0x27 114 340.68 us 12.61 us 2.99 us spinlock try_to_wake_up+0x1f5 83 226.38 us 9.15 us 2.73 us spinlock folio_lruvec_lock_irqsave+0x5e Committer notes: Make get_type_flag() return UINT_MAX for error instad of -1UL, as that function returns 'unsigned int' and we store the value on a 'unsigned int' 'flags' variable which makes clang unhappy: 35 98.23 fedora:37 : FAIL clang version 15.0.6 (Fedora 15.0.6-1.fc37) builtin-lock.c:2012:14: error: result of comparison of constant 18446744073709551615 with expression of type 'unsigned int' is always true [-Werror,-Wtautological-constant-out-of-range-compare] if (flags != -1UL) { ~~~~~ ^ ~~~~ builtin-lock.c:2021:14: error: result of comparison of constant 18446744073709551615 with expression of type 'unsigned int' is always true [-Werror,-Wtautological-constant-out-of-range-compare] if (flags != -1UL) { ~~~~~ ^ ~~~~ builtin-lock.c:2037:14: error: result of comparison of constant 18446744073709551615 with expression of type 'unsigned int' is always true [-Werror,-Wtautological-constant-out-of-range-compare] if (flags != -1UL) { ~~~~~ ^ ~~~~ 3 errors generated. Signed-off-by: Namhyung Kim Cc: Adrian Hunter Cc: Blake Jones Cc: Ian Rogers Cc: Ingo Molnar Cc: Jiri Olsa Cc: Peter Zijlstra Cc: Song Liu Cc: bpf@vger.kernel.org Link: https://lore.kernel.org/r/20221219201732.460111-3-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/Documentation/perf-lock.txt | 23 +++++-- tools/perf/builtin-lock.c | 116 ++++++++++++++++++++++++++++++++- tools/perf/util/lock-contention.h | 5 ++ 3 files changed, 136 insertions(+), 8 deletions(-) diff --git a/tools/perf/Documentation/perf-lock.txt b/tools/perf/Documentation/perf-lock.txt index 38e79d45..dea04ad 100644 --- a/tools/perf/Documentation/perf-lock.txt +++ b/tools/perf/Documentation/perf-lock.txt @@ -143,25 +143,25 @@ CONTENTION OPTIONS System-wide collection from all CPUs. -C:: ---cpu:: +--cpu=:: Collect samples only on the list of CPUs provided. Multiple CPUs can be provided as a comma-separated list with no space: 0,1. Ranges of CPUs are specified with -: 0-2. Default is to monitor all CPUs. -p:: ---pid=:: +--pid=:: Record events on existing process ID (comma separated list). ---tid=:: +--tid=:: Record events on existing thread ID (comma separated list). ---map-nr-entries:: +--map-nr-entries=:: Maximum number of BPF map entries (default: 10240). ---max-stack:: +--max-stack=:: Maximum stack depth when collecting lock contention (default: 8). ---stack-skip +--stack-skip=:: Number of stack depth to skip when finding a lock caller (default: 3). -E:: @@ -172,6 +172,17 @@ CONTENTION OPTIONS --lock-addr:: Show lock contention stat by address +-Y:: +--type-filter=:: + Show lock contention only for given lock types (comma separated list). + Available values are: + semaphore, spinlock, rwlock, rwlock:R, rwlock:W, rwsem, rwsem:R, rwsem:W, + rtmutex, rwlock-rt, rwlock-rt:R, rwlock-rt:W, pcpu-sem, pcpu-sem:R, pcpu-sem:W, + mutex + + Note that RW-variant of locks have :R and :W suffix. Names without the + suffix are shortcuts for the both variants. Ex) rwsem = rwsem:R + rwsem:W. + SEE ALSO -------- diff --git a/tools/perf/builtin-lock.c b/tools/perf/builtin-lock.c index 311f83b..c73d020 100644 --- a/tools/perf/builtin-lock.c +++ b/tools/perf/builtin-lock.c @@ -63,6 +63,8 @@ static int max_stack_depth = CONTENTION_STACK_DEPTH; static int stack_skip = CONTENTION_STACK_SKIP; static int print_nr_entries = INT_MAX / 2; +static struct lock_filter filters; + static enum lock_aggr_mode aggr_mode = LOCK_AGGR_ADDR; static struct thread_stat *thread_stat_find(u32 tid) @@ -990,8 +992,9 @@ static int report_lock_contention_begin_event(struct evsel *evsel, struct thread_stat *ts; struct lock_seq_stat *seq; u64 addr = evsel__intval(evsel, sample, "lock_addr"); + unsigned int flags = evsel__intval(evsel, sample, "flags"); u64 key; - int ret; + int i, ret; ret = get_key_by_aggr_mode(&key, addr, evsel, sample); if (ret < 0) @@ -1001,7 +1004,6 @@ static int report_lock_contention_begin_event(struct evsel *evsel, if (!ls) { char buf[128]; const char *name = ""; - unsigned int flags = evsel__intval(evsel, sample, "flags"); struct machine *machine = &session->machines.host; struct map *kmap; struct symbol *sym; @@ -1036,6 +1038,20 @@ static int report_lock_contention_begin_event(struct evsel *evsel, } } + if (filters.nr_types) { + bool found = false; + + for (i = 0; i < filters.nr_types; i++) { + if (flags == filters.types[i]) { + found = true; + break; + } + } + + if (!found) + return 0; + } + ts = thread_stat_findnew(sample->tid); if (!ts) return -ENOMEM; @@ -1454,6 +1470,8 @@ static const struct { { LCB_F_PERCPU | LCB_F_WRITE, "pcpu-sem:W" }, { LCB_F_MUTEX, "mutex" }, { LCB_F_MUTEX | LCB_F_SPIN, "mutex" }, + /* alias for get_type_flag() */ + { LCB_F_MUTEX | LCB_F_SPIN, "mutex-spin" }, }; static const char *get_type_str(unsigned int flags) @@ -1465,6 +1483,21 @@ static const char *get_type_str(unsigned int flags) return "unknown"; } +static unsigned int get_type_flag(const char *str) +{ + for (unsigned int i = 0; i < ARRAY_SIZE(lock_type_table); i++) { + if (!strcmp(lock_type_table[i].name, str)) + return lock_type_table[i].flags; + } + return UINT_MAX; +} + +static void lock_filter_finish(void) +{ + zfree(&filters.types); + filters.nr_types = 0; +} + static void sort_contention_result(void) { sort_result(); @@ -1507,6 +1540,9 @@ static void print_contention_result(struct lock_contention *con) if (st->broken) bad++; + if (!st->wait_time_total) + continue; + list_for_each_entry(key, &lock_keys, list) { key->print(key, st); pr_info(" "); @@ -1753,6 +1789,7 @@ static int __cmd_contention(int argc, const char **argv) print_contention_result(&con); out_delete: + lock_filter_finish(); evlist__delete(con.evlist); lock_contention_finish(); perf_session__delete(session); @@ -1884,6 +1921,79 @@ static int parse_max_stack(const struct option *opt, const char *str, return 0; } +static bool add_lock_type(unsigned int flags) +{ + unsigned int *tmp; + + tmp = realloc(filters.types, (filters.nr_types + 1) * sizeof(*filters.types)); + if (tmp == NULL) + return false; + + tmp[filters.nr_types++] = flags; + filters.types = tmp; + return true; +} + +static int parse_lock_type(const struct option *opt __maybe_unused, const char *str, + int unset __maybe_unused) +{ + char *s, *tmp, *tok; + int ret = 0; + + s = strdup(str); + if (s == NULL) + return -1; + + for (tok = strtok_r(s, ", ", &tmp); tok; tok = strtok_r(NULL, ", ", &tmp)) { + unsigned int flags = get_type_flag(tok); + + if (flags == -1U) { + char buf[32]; + + if (strchr(tok, ':')) + continue; + + /* try :R and :W suffixes for rwlock, rwsem, ... */ + scnprintf(buf, sizeof(buf), "%s:R", tok); + flags = get_type_flag(buf); + if (flags != UINT_MAX) { + if (!add_lock_type(flags)) { + ret = -1; + break; + } + } + + scnprintf(buf, sizeof(buf), "%s:W", tok); + flags = get_type_flag(buf); + if (flags != UINT_MAX) { + if (!add_lock_type(flags)) { + ret = -1; + break; + } + } + continue; + } + + if (!add_lock_type(flags)) { + ret = -1; + break; + } + + if (!strcmp(tok, "mutex")) { + flags = get_type_flag("mutex-spin"); + if (flags != UINT_MAX) { + if (!add_lock_type(flags)) { + ret = -1; + break; + } + } + } + } + + free(s); + return ret; +} + int cmd_lock(int argc, const char **argv) { const struct option lock_options[] = { @@ -1947,6 +2057,8 @@ int cmd_lock(int argc, const char **argv) "Default: " __stringify(CONTENTION_STACK_SKIP)), OPT_INTEGER('E', "entries", &print_nr_entries, "display this many functions"), OPT_BOOLEAN('l', "lock-addr", &show_lock_addrs, "show lock stats by address"), + OPT_CALLBACK('Y', "type-filter", NULL, "FLAGS", + "Filter specific type of locks", parse_lock_type), OPT_PARENT(lock_options) }; diff --git a/tools/perf/util/lock-contention.h b/tools/perf/util/lock-contention.h index 47fd47f..d5b75b2 100644 --- a/tools/perf/util/lock-contention.h +++ b/tools/perf/util/lock-contention.h @@ -5,6 +5,11 @@ #include #include +struct lock_filter { + int nr_types; + unsigned int *types; +}; + struct lock_stat { struct hlist_node hash_entry; struct rb_node rb; /* used for sorting */ -- 2.7.4