diff options
-rw-r--r-- | tools/perf/Documentation/perf-lock.txt | 5 | ||||
-rw-r--r-- | tools/perf/builtin-lock.c | 22 | ||||
-rw-r--r-- | tools/perf/util/bpf_lock_contention.c | 71 | ||||
-rw-r--r-- | tools/perf/util/lock-contention.h | 7 |
4 files changed, 94 insertions, 11 deletions
diff --git a/tools/perf/Documentation/perf-lock.txt b/tools/perf/Documentation/perf-lock.txt index d3793054f7d3..859dc11a7372 100644 --- a/tools/perf/Documentation/perf-lock.txt +++ b/tools/perf/Documentation/perf-lock.txt @@ -179,8 +179,9 @@ CONTENTION OPTIONS -o:: --lock-owner:: - Show lock contention stat by owners. Implies --threads and - requires --use-bpf. + Show lock contention stat by owners. This option can be combined with -t, + which shows owner's per thread lock stats, or -v, which shows owner's + stacktrace. Requires --use-bpf. -Y:: --type-filter=<value>:: diff --git a/tools/perf/builtin-lock.c b/tools/perf/builtin-lock.c index 9bebc186286f..05e7bc30488a 100644 --- a/tools/perf/builtin-lock.c +++ b/tools/perf/builtin-lock.c @@ -1817,6 +1817,22 @@ static void print_contention_result(struct lock_contention *con) break; } + if (con->owner && con->save_callstack && verbose > 0) { + struct rb_root root = RB_ROOT; + + if (symbol_conf.field_sep) + fprintf(lock_output, "# owner stack trace:\n"); + else + fprintf(lock_output, "\n=== owner stack trace ===\n\n"); + while ((st = pop_owner_stack_trace(con))) + insert_to(&root, st, compare); + + while ((st = pop_from(&root))) { + print_lock_stat(con, st); + free(st); + } + } + if (print_nr_entries) { /* update the total/bad stats */ while ((st = pop_from_result())) { @@ -1962,8 +1978,10 @@ static int check_lock_contention_options(const struct option *options, } } - if (show_lock_owner) - show_thread_stats = true; + if (show_lock_owner && !show_thread_stats) { + pr_warning("Now -o try to show owner's callstack instead of pid and comm.\n"); + pr_warning("Please use -t option too to keep the old behavior.\n"); + } return 0; } diff --git a/tools/perf/util/bpf_lock_contention.c b/tools/perf/util/bpf_lock_contention.c index 76542b86e83f..5af8f6d1bc95 100644 --- a/tools/perf/util/bpf_lock_contention.c +++ b/tools/perf/util/bpf_lock_contention.c @@ -460,7 +460,6 @@ static const char *lock_contention_get_name(struct lock_contention *con, { int idx = 0; u64 addr; - const char *name = ""; static char name_buf[KSYM_NAME_LEN]; struct symbol *sym; struct map *kmap; @@ -475,13 +474,14 @@ static const char *lock_contention_get_name(struct lock_contention *con, if (pid) { struct thread *t = machine__findnew_thread(machine, /*pid=*/-1, pid); - if (t == NULL) - return name; - if (!bpf_map_lookup_elem(task_fd, &pid, &task) && - thread__set_comm(t, task.comm, /*timestamp=*/0)) - name = task.comm; + if (t != NULL && + !bpf_map_lookup_elem(task_fd, &pid, &task) && + thread__set_comm(t, task.comm, /*timestamp=*/0)) { + snprintf(name_buf, sizeof(name_buf), "%s", task.comm); + return name_buf; + } } - return name; + return ""; } if (con->aggr_mode == LOCK_AGGR_ADDR) { @@ -549,6 +549,63 @@ static const char *lock_contention_get_name(struct lock_contention *con, return name_buf; } +struct lock_stat *pop_owner_stack_trace(struct lock_contention *con) +{ + int stacks_fd, stat_fd; + u64 *stack_trace = NULL; + s32 stack_id; + struct contention_key ckey = {}; + struct contention_data cdata = {}; + size_t stack_size = con->max_stack * sizeof(*stack_trace); + struct lock_stat *st = NULL; + + stacks_fd = bpf_map__fd(skel->maps.owner_stacks); + stat_fd = bpf_map__fd(skel->maps.owner_stat); + if (!stacks_fd || !stat_fd) + goto out_err; + + stack_trace = zalloc(stack_size); + if (stack_trace == NULL) + goto out_err; + + if (bpf_map_get_next_key(stacks_fd, NULL, stack_trace)) + goto out_err; + + bpf_map_lookup_elem(stacks_fd, stack_trace, &stack_id); + ckey.stack_id = stack_id; + bpf_map_lookup_elem(stat_fd, &ckey, &cdata); + + st = zalloc(sizeof(struct lock_stat)); + if (!st) + goto out_err; + + st->name = strdup(stack_trace[0] ? lock_contention_get_name(con, NULL, stack_trace, 0) : + "unknown"); + if (!st->name) + goto out_err; + + st->flags = cdata.flags; + st->nr_contended = cdata.count; + st->wait_time_total = cdata.total_time; + st->wait_time_max = cdata.max_time; + st->wait_time_min = cdata.min_time; + st->callstack = stack_trace; + + if (cdata.count) + st->avg_wait_time = cdata.total_time / cdata.count; + + bpf_map_delete_elem(stacks_fd, stack_trace); + bpf_map_delete_elem(stat_fd, &ckey); + + return st; + +out_err: + free(stack_trace); + free(st); + + return NULL; +} + int lock_contention_read(struct lock_contention *con) { int fd, stack, err = 0; diff --git a/tools/perf/util/lock-contention.h b/tools/perf/util/lock-contention.h index a09f7fe877df..b5d916aa49df 100644 --- a/tools/perf/util/lock-contention.h +++ b/tools/perf/util/lock-contention.h @@ -168,6 +168,8 @@ int lock_contention_stop(void); int lock_contention_read(struct lock_contention *con); int lock_contention_finish(struct lock_contention *con); +struct lock_stat *pop_owner_stack_trace(struct lock_contention *con); + #else /* !HAVE_BPF_SKEL */ static inline int lock_contention_prepare(struct lock_contention *con __maybe_unused) @@ -187,6 +189,11 @@ static inline int lock_contention_read(struct lock_contention *con __maybe_unuse return 0; } +static inline struct lock_stat *pop_owner_stack_trace(struct lock_contention *con __maybe_unused) +{ + return NULL; +} + #endif /* HAVE_BPF_SKEL */ #endif /* PERF_LOCK_CONTENTION_H */ |