[PATCH 03/12] time: Complete NTP adjustment threshold judging conditions

From: John Stultz
Date: Fri Nov 21 2014 - 14:48:12 EST

From: "pang.xunlei" <pang.xunlei@xxxxxxxxxx>

The clocksource mult-adjustment threshold is [mult-maxadj, mult+maxadj],
timekeeping_adjust() only deals with the upper threshold, but misses the
lower threshold.

This patch adds the lower threshold judging condition.

Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxx>
Cc: Arnd Bergmann <arnd.bergmann@xxxxxxxxxx>
Cc: pang.xunlei <pang.xunlei@xxxxxxxxxx>
Cc: Miroslav Lichvar <mlichvar@xxxxxxxxxx>
Cc: Richard Cochran <richardcochran@xxxxxxxxx>
Cc: Prarit Bhargava <prarit@xxxxxxxxxx>
Cc: Alessandro Zummo <a.zummo@xxxxxxxxxxxx>
Signed-off-by: pang.xunlei <pang.xunlei@xxxxxxxxxx>
[jstultz: Minor fix for > 80 char line]
Signed-off-by: John Stultz <john.stultz@xxxxxxxxxx>
kernel/time/timekeeping.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index cad61b3..41fcbe1 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -1403,7 +1403,8 @@ static void timekeeping_adjust(struct timekeeper *tk, s64 offset)

if (unlikely(tk->tkr.clock->maxadj &&
- (tk->tkr.mult > tk->tkr.clock->mult + tk->tkr.clock->maxadj))) {
+ (abs(tk->tkr.mult - tk->tkr.clock->mult)
+ > tk->tkr.clock->maxadj))) {
"Adjusting %s more than 11%% (%ld vs %ld)\n",
tk->tkr.clock->name, (long)tk->tkr.mult,

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/