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| author | John Stultz <john.stultz@linaro.org> | 2013-12-10 17:13:35 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-02-13 13:50:26 -0800 |
| commit | aaa5ad29bc420c04cb0df5e4d6876aa32096b7d0 (patch) | |
| tree | ff7f61c7c8e58cd29d88208f40ae2d879e9edfa6 | |
| parent | e14bada985c4af6d192413ad72dc35758cffe286 (diff) | |
| download | lwn-aaa5ad29bc420c04cb0df5e4d6876aa32096b7d0.tar.gz lwn-aaa5ad29bc420c04cb0df5e4d6876aa32096b7d0.zip | |
timekeeping: Fix CLOCK_TAI timer/nanosleep delays
commit 04005f6011e3b504cd4d791d9769f7cb9a3b2eae upstream.
A think-o in the calculation of the monotonic -> tai time offset
results in CLOCK_TAI timers and nanosleeps to expire late (the
latency is ~2x the tai offset).
Fix this by adding the tai offset from the realtime offset instead
of subtracting.
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | kernel/time/timekeeping.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index f223826e60f7..cd0c38427d51 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -77,7 +77,7 @@ static void tk_set_wall_to_mono(struct timekeeper *tk, struct timespec wtm) tk->wall_to_monotonic = wtm; set_normalized_timespec(&tmp, -wtm.tv_sec, -wtm.tv_nsec); tk->offs_real = timespec_to_ktime(tmp); - tk->offs_tai = ktime_sub(tk->offs_real, ktime_set(tk->tai_offset, 0)); + tk->offs_tai = ktime_add(tk->offs_real, ktime_set(tk->tai_offset, 0)); } static void tk_set_sleep_time(struct timekeeper *tk, struct timespec t) @@ -595,7 +595,7 @@ s32 timekeeping_get_tai_offset(void) static void __timekeeping_set_tai_offset(struct timekeeper *tk, s32 tai_offset) { tk->tai_offset = tai_offset; - tk->offs_tai = ktime_sub(tk->offs_real, ktime_set(tai_offset, 0)); + tk->offs_tai = ktime_add(tk->offs_real, ktime_set(tai_offset, 0)); } /** |