[PATCH 2/8] Cpuidle: Rearrange code and comments in get_typical_interval()

From: tuukka . tikkanen
Date: Wed Aug 14 2013 - 12:18:54 EST


From: Tuukka Tikkanen <tuukka.tikkanen@xxxxxxxxxx>

This patch rearranges a if-return-elsif-goto-fi-return sequence into
if-return-fi-if-return-fi-goto sequence. The functionality remains the
same. Also, a lengthy comment that did not describe the functionality
in the order it occurs is split into half and top half is moved closer
to actual implementation it describes.

Signed-off-by: Tuukka Tikkanen <tuukka.tikkanen@xxxxxxxxxx>
---
drivers/cpuidle/governors/menu.c | 28 +++++++++++++++-------------
1 file changed, 15 insertions(+), 13 deletions(-)

diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c
index c8ab1c5..b13d57c 100644
--- a/drivers/cpuidle/governors/menu.c
+++ b/drivers/cpuidle/governors/menu.c
@@ -228,14 +228,6 @@ again:
do_div(stddev, divisor);
stddev = int_sqrt(stddev);
/*
- * If we have outliers to the upside in our distribution, discard
- * those by setting the threshold to exclude these outliers, then
- * calculate the average and standard deviation again. Once we get
- * down to the bottom 3/4 of our samples, stop excluding samples.
- *
- * This can deal with workloads that have long pauses interspersed
- * with sporadic activity with a bunch of short pauses.
- *
* The typical interval is obtained when standard deviation is small
* or standard deviation is small compared to the average interval.
*
@@ -246,12 +238,22 @@ again:
if (data->expected_us > avg)
data->predicted_us = avg;
return;
-
- } else if ((divisor * 4) > INTERVALS * 3) {
- /* Exclude the max interval */
- thresh = max - 1;
- goto again;
}
+
+ /*
+ * If we have outliers to the upside in our distribution, discard
+ * those by setting the threshold to exclude these outliers, then
+ * calculate the average and standard deviation again. Once we get
+ * down to the bottom 3/4 of our samples, stop excluding samples.
+ *
+ * This can deal with workloads that have long pauses interspersed
+ * with sporadic activity with a bunch of short pauses.
+ */
+ if ((divisor * 4) <= INTERVALS * 3)
+ return;
+
+ thresh = max - 1;
+ goto again;
}

/**
--
1.7.9.5

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/