perf session: Don't report zero period samples for slave events

There's no reason to deliver a sample with zero period.  It means there
was no value for slave event since its last group leader sample.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190220122800.864-2-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index 18fb9c8..c764bbc 100644 (file)
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -1202,6 +1202,13 @@ static int deliver_sample_value(struct perf_evlist *evlist,
                return 0;
        }
 
+       /*
+        * There's no reason to deliver sample
+        * for zero period, bail out.
+        */
+       if (!sample->period)
+               return 0;
+
        return tool->sample(tool, event, sample, sid->evsel, machine);
 }