[tip:perf/urgent] perf stat: Do not clean event's private stats

[tip-bot for Jiri Olsa]

Commit-ID:  3f416f22d1e21709a631189ba169f76fd267b374
Gitweb:     http://git.kernel.org/tip/3f416f22d1e21709a631189ba169f76fd267b374
Author:     Jiri Olsa <jolsa@xxxxxxxxxx>
AuthorDate: Wed, 20 Jan 2016 12:56:34 +0100
Committer:  Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitDate: Tue, 26 Jan 2016 11:15:11 -0300

perf stat: Do not clean event's private stats

Mel reported stddev reporting was broken due to following commit:

	106a94a0f8c2 ("perf stat: Introduce read_counters function")

This commit merged interval and overall counters reading into single
read_counters function.

The old interval code cleaned the stddev data for some reason (it's
never displayed in interval mode) and the mentioned commit kept on
cleaning the stddev data in merged function, which resulted in the
stddev not being displayed.

Removing the wrong stddev data cleanup init_stats call.

Reported-and-Tested-by: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: David Ahern <dsahern@xxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx # v4.2+
Fixes: 106a94a0f8c2 ("perf stat: Introduce read_counters function")
Link: http://lkml.kernel.org/r/1453290995-18485-4-git-send-email-jolsa@xxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
 tools/perf/util/stat.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/tools/perf/util/stat.c b/tools/perf/util/stat.c
index 2f901d1..2b58edc 100644
--- a/tools/perf/util/stat.c
+++ b/tools/perf/util/stat.c
@@ -310,7 +310,6 @@ int perf_stat_process_counter(struct perf_stat_config *config,
 	int i, ret;
 
 	aggr->val = aggr->ena = aggr->run = 0;
-	init_stats(ps->res_stats);
 
 	if (counter->per_pkg)
 		zero_per_pkg(counter);