diff options
| author | Yang Honggang (Joseph) <eagle.rtlinux@gmail.com> | 2011-12-01 22:22:41 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-12-09 08:52:52 -0800 |
| commit | 4078977c46f627f553ed2d8ea047b9bf25dee48d (patch) | |
| tree | fd257cf2fde90205159813141edc07102e387901 /kernel | |
| parent | 0bbf5c70251286fbc3b7aac5e7961b4568115bfd (diff) | |
clocksource: Fix bug with max_deferment margin calculation
commit b1f919664d04a8d0ba29cb76673c7ca3325a2006 upstream.
In order to leave a margin of 12.5% we should >> 3 not >> 5.
Signed-off-by: Yang Honggang (Joseph) <eagle.rtlinux@gmail.com>
[jstultz: Modified commit subject]
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/time/clocksource.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index e0980f0d9a0a..8b270063b515 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -531,7 +531,7 @@ static u64 clocksource_max_deferment(struct clocksource *cs) * note a margin of 12.5% is used because this can be computed with * a shift, versus say 10% which would require division. */ - return max_nsecs - (max_nsecs >> 5); + return max_nsecs - (max_nsecs >> 3); } #ifndef CONFIG_ARCH_USES_GETTIMEOFFSET @@ -653,7 +653,7 @@ void __clocksource_updatefreq_scale(struct clocksource *cs, u32 scale, u32 freq) * ~ 0.06ppm granularity for NTP. We apply the same 12.5% * margin as we do in clocksource_max_deferment() */ - sec = (cs->mask - (cs->mask >> 5)); + sec = (cs->mask - (cs->mask >> 3)); do_div(sec, freq); do_div(sec, scale); if (!sec) |