From: Yang Honggang (Joseph) <eagle.rtlinux@gmail.com>
Date: Fri, 2 Dec 2011 03:22:41 +0000 (-0500)
Subject: clocksource: Fix bug with max_deferment margin calculation
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=b1f919664d04a8d0ba29cb76673c7ca3325a2006;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git

clocksource: Fix bug with max_deferment margin calculation

In order to leave a margin of 12.5% we should >> 3 not >> 5.

CC: stable@kernel.org
Signed-off-by: Yang Honggang (Joseph) <eagle.rtlinux@gmail.com>
[jstultz: Modified commit subject]
Signed-off-by: John Stultz <john.stultz@linaro.org>
---

diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c
index cfc65e1eb9fb..da2f760e780c 100644
--- a/kernel/time/clocksource.c
+++ b/kernel/time/clocksource.c
@@ -548,7 +548,7 @@ 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
@@ -669,7 +669,7 @@ 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)