timekeeping: Fix CLOCK_MONOTONIC inconsistency during leapsecond

commit fad0c66c4bb836d57a5f125ecd38bed653ca863a upstream.
which resolves a bug the previous commit.

Commit 6b43ae8a61 (ntp: Fix leap-second hrtimer livelock) broke the
leapsecond update of CLOCK_MONOTONIC. The missing leapsecond update to
wall_to_monotonic causes discontinuities in CLOCK_MONOTONIC.

Adjust wall_to_monotonic when NTP inserted a leapsecond.

Reported-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Tested-by: Richard Cochran <richardcochran@gmail.com>
Link: http://lkml.kernel.org/r/1338400497-12420-1-git-send-email-john.stultz@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Linux Kernel <linux-kernel@vger.kernel.org>
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index df1e9397b55a8a2f62ed8ff0f899b7d553cadce2..f8d4877687ff1ca25624d2da82a93f665e27dfae 100644 (file)
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -759,6 +759,7 @@ static cycle_t logarithmic_accumulation(cycle_t offset, int shift)
                xtime.tv_sec++;
                leap = second_overflow(xtime.tv_sec);
                xtime.tv_sec += leap;
+               wall_to_monotonic.tv_sec -= leap;
        }
 
        /* Accumulate into raw time */