[PATCH 03/13] perf, tools, stat: Handle partially bad results with merging

From: Andi Kleen
Date: Mon Mar 20 2017 - 16:17:38 EST


From: Andi Kleen <ak@xxxxxxxxxxxxxxx>

When any result that is being merged is bad, mark them all
bad to give consistent output in interval mode.

No before/after, because the issue was only found in theoretical
review and it is hard to reproduce

Signed-off-by: Andi Kleen <ak@xxxxxxxxxxxxxxx>
---
tools/perf/builtin-stat.c | 10 ++++++++++
1 file changed, 10 insertions(+)

diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index a4da10a506dd..cd7dc3b648ca 100644
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -1237,6 +1237,16 @@ static void aggr_cb(struct perf_evsel *counter, void *data, bool first)
if (first)
ad->nr++;
counts = perf_counts(counter->counts, cpu, 0);
+ /*
+ * When any result is bad, make them all to give
+ * consistent output in interval mode.
+ */
+ if (counts->ena == 0 || counts->run == 0 ||
+ counter->counts->scaled == -1) {
+ ad->ena = 0;
+ ad->run = 0;
+ break;
+ }
ad->val += counts->val;
ad->ena += counts->ena;
ad->run += counts->run;
--
2.9.3