perf stat record: Keep sample_type 0 for pipe session

For pipe sessions we need to keep sample_type zero, because script's
perf_evsel__check_attr is triggered by sample_type != 0, and the check
would fail on stat session.

I was tempted to keep it zero unconditionally, but the pipe session is
sufficient. In perf.data session we are guarded by HEADER_STAT feature.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1452028152-26762-2-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index 9805e03..7f56824 100644 (file)
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -184,11 +184,18 @@ static int create_perf_stat_counter(struct perf_evsel *evsel)
         * like tracepoints. Clear it up for counting.
         */
        attr->sample_period = 0;
+
        /*
         * But set sample_type to PERF_SAMPLE_IDENTIFIER, which should be harmless
         * while avoiding that older tools show confusing messages.
+        *
+        * However for pipe sessions we need to keep it zero,
+        * because script's perf_evsel__check_attr is triggered
+        * by attr->sample_type != 0, and we can't run it on
+        * stat sessions.
         */
-       attr->sample_type   = PERF_SAMPLE_IDENTIFIER;
+       if (!(STAT_RECORD && perf_stat.file.is_pipe))
+               attr->sample_type = PERF_SAMPLE_IDENTIFIER;
 
        /*
         * Disabling all counters initially, they will be enabled