[PATCH] cpuidle: fix bug in the pattern detector as reported by Frank Rowand

[Arjan van de Ven]

Frank Rowand found a bug in the new pattern detector code where
the average value was looked at before the sum of values got divided
by the number of samples.

Signed-off-by: Arjan van de Ven <arjan@xxxxxxxxxxxxxxx>
CC: akpm@xxxxxxxxxxxxxxxxxxxx
CC: frank.rowand@xxxxxxxxxxx
---
 drivers/cpuidle/governors/menu.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c
index f3d4783..52ff8aa 100644
--- a/drivers/cpuidle/governors/menu.c
+++ b/drivers/cpuidle/governors/menu.c
@@ -205,12 +205,12 @@ static void detect_repeating_patterns(struct menu_device *data)
 	/* first calculate average and standard deviation of the past */
 	for (i = 0; i < INTERVALS; i++)
 		avg += data->intervals[i];
+	avg = avg / INTERVALS;
 
 	/* if the avg is beyond the known next tick, it's worthless */
 	if (avg > data->expected_us)
 		return;
 
-	avg = avg / INTERVALS;
 	for (i = 0; i < INTERVALS; i++)
 		stddev += (data->intervals[i] - avg) *
 			  (data->intervals[i] - avg);
-- 
1.6.2.5

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