[PATCH] time: Fix CLOCK_MONOTONIC inconsistency during leapsecond

From: John Stultz
Date: Wed May 30 2012 - 13:56:35 EST


Make sure we update wall_to_monotonic when adding a leapsecond.
This could otherwise cause discontinuities in CLOCK_MONOTONIC.

This fixes a regression caused by
6b43ae8a619d17c4935c3320d2ef9e92bdeed05d

CC: stable@xxxxxxxxxx
CC: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Reported-by: Richard Cochran <richardcochran@xxxxxxxxx>
Tested-by: Richard Cochran <richardcochran@xxxxxxxxx>
Signed-off-by: John Stultz <john.stultz@xxxxxxxxxx>
---
kernel/time/timekeeping.c | 2 ++
1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index 6e46cac..6f46a00 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -962,6 +962,7 @@ static cycle_t logarithmic_accumulation(cycle_t offset, int shift)
timekeeper.xtime.tv_sec++;
leap = second_overflow(timekeeper.xtime.tv_sec);
timekeeper.xtime.tv_sec += leap;
+ timekeeper.wall_to_monotonic.tv_sec -= leap;
}

/* Accumulate raw time */
@@ -1077,6 +1078,7 @@ static void update_wall_time(void)
timekeeper.xtime.tv_sec++;
leap = second_overflow(timekeeper.xtime.tv_sec);
timekeeper.xtime.tv_sec += leap;
+ timekeeper.wall_to_monotonic.tv_sec -= leap;
}

timekeeping_update(false);
--
1.7.3.2.146.gca209

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