[PATCH 7/8] timekeeping: Simplify tai updating from do_adjtimex

From: John Stultz
Date: Mon Mar 25 2013 - 16:09:01 EST


Since we are taking the timekeeping locks, just go ahead
and update any tai change directly, rather then dropping
the lock and calling a function that will just take it again.

Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Richard Cochran <richardcochran@xxxxxxxxx>
Cc: Prarit Bhargava <prarit@xxxxxxxxxx>
Signed-off-by: John Stultz <john.stultz@xxxxxxxxxx>
---
kernel/time/timekeeping.c | 9 ++++-----
1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index d10bd73..f93f60c 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -1618,9 +1618,10 @@ EXPORT_SYMBOL_GPL(ktime_get_monotonic_offset);
*/
int do_adjtimex(struct timex *txc)
{
+ struct timekeeper *tk = &timekeeper;
unsigned long flags;
struct timespec ts;
- s32 tai, orig_tai;
+ s32 tai;
int ret;

/* Validate the data before disabling interrupts */
@@ -1640,19 +1641,17 @@ int do_adjtimex(struct timex *txc)
}

getnstimeofday(&ts);
- orig_tai = tai = timekeeping_get_tai_offset();

raw_spin_lock_irqsave(&timekeeper_lock, flags);
write_seqcount_begin(&timekeeper_seq);

+ tai = tk->tai_offset;
ret = __do_adjtimex(txc, &ts, &tai);

+ __timekeeping_set_tai_offset(tk, tai);
write_seqcount_end(&timekeeper_seq);
raw_spin_unlock_irqrestore(&timekeeper_lock, flags);

- if (tai != orig_tai)
- timekeeping_set_tai_offset(tai);
-
return ret;
}

--
1.7.10.4

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