From 1811e82767dcc6ebfdb2a57877f1756f067990b8 Mon Sep 17 00:00:00 2001 From: Namhyung Kim Date: Mon, 13 Mar 2023 13:48:23 -0700 Subject: [PATCH] perf lock contention: Track and show siglock with address Likewise, we can display siglock by following the pointer like current->sighand->siglock. $ sudo ./perf lock con -abl -- sleep 1 contended total wait max wait avg wait address symbol 16 2.18 ms 305.35 us 136.34 us ffffffff92e06080 tasklist_lock 28 521.78 us 31.16 us 18.63 us ffff8cc703783ec4 7 119.03 us 23.55 us 17.00 us ffff8ccb92479440 15 88.29 us 10.06 us 5.89 us ffff8cd560b5f380 siglock 7 37.67 us 9.16 us 5.38 us ffff8d053daf0c80 5 8.81 us 4.92 us 1.76 us ffff8d053d6b0c80 Signed-off-by: Namhyung Kim Cc: Boqun Feng Cc: Hao Luo Cc: Ingo Molnar Cc: Jiri Olsa Cc: Juri Lelli Cc: Peter Zijlstra Cc: Song Liu Cc: Stephane Eranian Cc: Waiman Long Cc: Will Deacon Cc: bpf@vger.kernel.org Link: https://lore.kernel.org/r/20230313204825.2665483-2-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-lock.c | 3 +-- tools/perf/util/bpf_lock_contention.c | 8 ++++++-- tools/perf/util/bpf_skel/lock_contention.bpf.c | 5 +++++ tools/perf/util/bpf_skel/lock_data.h | 3 ++- 4 files changed, 14 insertions(+), 5 deletions(-) diff --git a/tools/perf/builtin-lock.c b/tools/perf/builtin-lock.c index 1b0dc94..28fa0d0 100644 --- a/tools/perf/builtin-lock.c +++ b/tools/perf/builtin-lock.c @@ -1662,8 +1662,7 @@ static void print_contention_result(struct lock_contention *con) pid, pid == -1 ? "Unknown" : thread__comm_str(t)); break; case LOCK_AGGR_ADDR: - pr_info(" %016llx %s\n", (unsigned long long)st->addr, - (st->flags & LCD_F_MMAP_LOCK) ? "mmap_lock" : st->name); + pr_info(" %016llx %s\n", (unsigned long long)st->addr, st->name); break; default: break; diff --git a/tools/perf/util/bpf_lock_contention.c b/tools/perf/util/bpf_lock_contention.c index fadcacb..51631af 100644 --- a/tools/perf/util/bpf_lock_contention.c +++ b/tools/perf/util/bpf_lock_contention.c @@ -169,7 +169,7 @@ int lock_contention_stop(void) static const char *lock_contention_get_name(struct lock_contention *con, struct contention_key *key, - u64 *stack_trace) + u64 *stack_trace, u32 flags) { int idx = 0; u64 addr; @@ -198,6 +198,10 @@ static const char *lock_contention_get_name(struct lock_contention *con, } if (con->aggr_mode == LOCK_AGGR_ADDR) { + if (flags & LCD_F_MMAP_LOCK) + return "mmap_lock"; + if (flags & LCD_F_SIGHAND_LOCK) + return "siglock"; sym = machine__find_kernel_symbol(machine, key->lock_addr, &kmap); if (sym) name = sym->name; @@ -301,7 +305,7 @@ int lock_contention_read(struct lock_contention *con) goto next; } - name = lock_contention_get_name(con, &key, stack_trace); + name = lock_contention_get_name(con, &key, stack_trace, data.flags); st = lock_stat_findnew(ls_key, name, data.flags); if (st == NULL) break; diff --git a/tools/perf/util/bpf_skel/lock_contention.bpf.c b/tools/perf/util/bpf_skel/lock_contention.bpf.c index 40ee3df..f76cde0 100644 --- a/tools/perf/util/bpf_skel/lock_contention.bpf.c +++ b/tools/perf/util/bpf_skel/lock_contention.bpf.c @@ -242,6 +242,11 @@ static inline __u32 check_lock_type(__u64 lock, __u32 flags) return LCD_F_MMAP_LOCK; } break; + case LCB_F_SPIN: /* spinlock */ + curr = bpf_get_current_task_btf(); + if (&curr->sighand->siglock == (void *)lock) + return LCD_F_SIGHAND_LOCK; + break; default: break; } diff --git a/tools/perf/util/bpf_skel/lock_data.h b/tools/perf/util/bpf_skel/lock_data.h index 789f208..5ed1a09 100644 --- a/tools/perf/util/bpf_skel/lock_data.h +++ b/tools/perf/util/bpf_skel/lock_data.h @@ -19,7 +19,8 @@ struct contention_task_data { * Upper bits of the flags in the contention_data are used to identify * some well-known locks which do not have symbols (non-global locks). */ -#define LCD_F_MMAP_LOCK (1U << 31) +#define LCD_F_MMAP_LOCK (1U << 31) +#define LCD_F_SIGHAND_LOCK (1U << 30) struct contention_data { u64 total_time; -- 2.7.4