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 <namhyung@kernel.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Hao Luo <haoluo@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <song@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will@kernel.org>
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20230313204825.2665483-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/builtin-lock.c b/tools/perf/builtin-lock.c
index 1b0dc94..28fa0d0 100644 (file)
--- 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 (file)
--- 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 (file)
--- 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 (file)
--- 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;