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* [PATCH] perf stat: Fix duration_time value for higher intervals
@ 2020-05-18 13:14 Jiri Olsa
  2020-05-18 15:23 ` Arnaldo Carvalho de Melo
  0 siblings, 1 reply; 3+ messages in thread
From: Jiri Olsa @ 2020-05-18 13:14 UTC (permalink / raw)
  To: Arnaldo Carvalho de Melo
  Cc: Joakim Zhang, lkml, Ingo Molnar, Namhyung Kim, Alexander Shishkin,
	Peter Zijlstra, Michael Petlan

Joakim reported wrong duration_time value for interval bigger
than 4000 [1].

The problem is in the interval value we pass to update_stats
function, which is typed as 'unsigned int' and overflows when
we get over 2^32 (happens between intervals 4000 and 5000).

Retyping the passed value to unsigned long long.

[1] https://www.spinics.net/lists/linux-perf-users/msg11777.html

Reported-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
 tools/perf/builtin-stat.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index e0c1ad23c768..4deb2d46a343 100644
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -367,7 +367,7 @@ static void process_interval(void)
 	}
 
 	init_stats(&walltime_nsecs_stats);
-	update_stats(&walltime_nsecs_stats, stat_config.interval * 1000000);
+	update_stats(&walltime_nsecs_stats, stat_config.interval * 1000000ULL);
 	print_counters(&rs, 0, NULL);
 }
 
-- 
2.25.4


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2020-05-18 13:14 [PATCH] perf stat: Fix duration_time value for higher intervals Jiri Olsa
2020-05-18 15:23 ` Arnaldo Carvalho de Melo
2020-05-18 15:48   ` Jiri Olsa

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