perf lock: Carefully combine lock stats for discarded entries
Stats from discarded entries should be omitted. But a lock class may
have both good and bad entries. If the first entry was bad, we can
zero-fill the stats and only add good stats if any. The entry can
remove the discard state if it finds a good entry later.
Acked-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
diff --git a/tools/perf/builtin-lock.c b/tools/perf/builtin-lock.c
index bbfeba7..57b9ebd 100644
--- a/tools/perf/builtin-lock.c
+++ b/tools/perf/builtin-lock.c
@@ -295,6 +295,9 @@ static void combine_lock_stats(struct lock_stat *st)
ret = !!st->name - !!p->name;
if (ret == 0) {
+ if (st->discard)
+ goto out;
+
p->nr_acquired += st->nr_acquired;
p->nr_contended += st->nr_contended;
p->wait_time_total += st->wait_time_total;
@@ -307,6 +310,10 @@ static void combine_lock_stats(struct lock_stat *st)
if (p->wait_time_max < st->wait_time_max)
p->wait_time_max = st->wait_time_max;
+ /* now it got a new !discard record */
+ p->discard = 0;
+
+out:
st->combined = 1;
return;
}
@@ -319,6 +326,15 @@ static void combine_lock_stats(struct lock_stat *st)
rb_link_node(&st->rb, parent, rb);
rb_insert_color(&st->rb, &sorted);
+
+ if (st->discard) {
+ st->nr_acquired = 0;
+ st->nr_contended = 0;
+ st->wait_time_total = 0;
+ st->avg_wait_time = 0;
+ st->wait_time_min = ULLONG_MAX;
+ st->wait_time_max = 0;
+ }
}
static void insert_to_result(struct lock_stat *st,
