[PATCH 1/4] watchdog: fix rounding issues in get_sample_period()

From: Mandeep Singh Baines
Date: Mon May 23 2011 - 01:11:58 EST


In get_sample_period(), softlockup_thresh is integer divided by 5 before
the multiplication by NSEC_PER_SEC. This results in softlockup_thresh
being rounded down to the nearest integer multiple of 5.

For example, a softlockup_thresh of 4 rounds down to 0.

Signed-off-by: Mandeep Singh Baines <msb@xxxxxxxxxxxx>
Cc: Marcin Slusarz <marcin.slusarz@xxxxxxxxx>
Cc: Don Zickus <dzickus@xxxxxxxxxx>
Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Cc: Frederic Weisbecker <fweisbec@xxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
kernel/watchdog.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/kernel/watchdog.c b/kernel/watchdog.c
index 14733d4..a06972d 100644
--- a/kernel/watchdog.c
+++ b/kernel/watchdog.c
@@ -110,7 +110,7 @@ static unsigned long get_sample_period(void)
* increment before the hardlockup detector generates
* a warning
*/
- return softlockup_thresh / 5 * NSEC_PER_SEC;
+ return softlockup_thresh * (NSEC_PER_SEC / 5);
}

/* Commands for resetting the watchdog */
--
1.7.3.1

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