time: Refactor accumulation of nsecs to secs
authorJohn Stultz <john.stultz@linaro.org>
Fri, 13 Jul 2012 05:21:54 +0000 (01:21 -0400)
committerThomas Gleixner <tglx@linutronix.de>
Sun, 15 Jul 2012 08:39:06 +0000 (10:39 +0200)
We do the exact same logic moving nsecs to secs in the
timekeeper in multiple places, so condense this into a
single function.

Signed-off-by: John Stultz <john.stultz@linaro.org>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Link: http://lkml.kernel.org/r/1342156917-25092-6-git-send-email-john.stultz@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
kernel/time/timekeeping.c

index b98d9bd73e5e041cc04b893b56720d8b0268d57d..cb4a433bab976dbf205e3209566ddd67da914019 100644 (file)
@@ -990,6 +990,35 @@ static void timekeeping_adjust(s64 offset)
 }
 
 
+/**
+ * accumulate_nsecs_to_secs - Accumulates nsecs into secs
+ *
+ * Helper function that accumulates a the nsecs greater then a second
+ * from the xtime_nsec field to the xtime_secs field.
+ * It also calls into the NTP code to handle leapsecond processing.
+ *
+ */
+static inline void accumulate_nsecs_to_secs(struct timekeeper *tk)
+{
+       u64 nsecps = (u64)NSEC_PER_SEC << tk->shift;
+
+       while (tk->xtime_nsec >= nsecps) {
+               int leap;
+
+               tk->xtime_nsec -= nsecps;
+               tk->xtime_sec++;
+
+               /* Figure out if its a leap sec and apply if needed */
+               leap = second_overflow(tk->xtime_sec);
+               tk->xtime_sec += leap;
+               tk->wall_to_monotonic.tv_sec -= leap;
+               if (leap)
+                       clock_was_set_delayed();
+
+       }
+}
+
+
 /**
  * logarithmic_accumulation - shifted accumulation of cycles
  *
@@ -1001,7 +1030,6 @@ static void timekeeping_adjust(s64 offset)
  */
 static cycle_t logarithmic_accumulation(cycle_t offset, u32 shift)
 {
-       u64 nsecps = (u64)NSEC_PER_SEC << timekeeper.shift;
        u64 raw_nsecs;
 
        /* If the offset is smaller than a shifted interval, do nothing */
@@ -1013,16 +1041,8 @@ static cycle_t logarithmic_accumulation(cycle_t offset, u32 shift)
        timekeeper.clock->cycle_last += timekeeper.cycle_interval << shift;
 
        timekeeper.xtime_nsec += timekeeper.xtime_interval << shift;
-       while (timekeeper.xtime_nsec >= nsecps) {
-               int leap;
-               timekeeper.xtime_nsec -= nsecps;
-               timekeeper.xtime_sec++;
-               leap = second_overflow(timekeeper.xtime_sec);
-               timekeeper.xtime_sec += leap;
-               timekeeper.wall_to_monotonic.tv_sec -= leap;
-               if (leap)
-                       clock_was_set_delayed();
-       }
+
+       accumulate_nsecs_to_secs(&timekeeper);
 
        /* Accumulate raw time */
        raw_nsecs = timekeeper.raw_interval << shift;
@@ -1132,17 +1152,7 @@ static void update_wall_time(void)
         * Finally, make sure that after the rounding
         * xtime_nsec isn't larger than NSEC_PER_SEC
         */
-       if (unlikely(timekeeper.xtime_nsec >=
-                       ((u64)NSEC_PER_SEC << timekeeper.shift))) {
-               int leap;
-               timekeeper.xtime_nsec -= (u64)NSEC_PER_SEC << timekeeper.shift;
-               timekeeper.xtime_sec++;
-               leap = second_overflow(timekeeper.xtime_sec);
-               timekeeper.xtime_sec += leap;
-               timekeeper.wall_to_monotonic.tv_sec -= leap;
-               if (leap)
-                       clock_was_set_delayed();
-       }
+       accumulate_nsecs_to_secs(&timekeeper);
 
        timekeeping_update(false);