[PATCH 1/8] perf stat record: Keep sample_type 0 for pipe session

[Jiri Olsa <jolsa@kernel.org>]

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.

Link: http://lkml.kernel.org/n/tip-77k0kpd1c9beill47ceo8fp3@git.kernel.org
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
 tools/perf/builtin-stat.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index 9805e03ab163..7f568244662b 100644
--- 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
-- 
2.4.3