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

[Andi Kleen]

From: Andi Kleen <a...@linux.intel.com>

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 <a...@linux.intel.com>
---
 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