summaryrefslogtreecommitdiffstats
path: root/kernel/time
diff options
context:
space:
mode:
authorThomas Gleixner <tglx@linutronix.de>2016-07-04 09:50:37 +0000
committerIngo Molnar <mingo@kernel.org>2016-07-07 10:35:11 +0200
commit4e85876a9d2a977b4a07389da8c07edf76d10825 (patch)
tree4e0d4f1ba711f1c737309211a4c097c4ac994b94 /kernel/time
parenta683f390b93f4d1292f849fc48d28e322046120f (diff)
downloadlinux-4e85876a9d2a977b4a07389da8c07edf76d10825.tar.bz2
timers: Only wake softirq if necessary
With the wheel forwading in place and with the HZ=1000 4ms folding we can avoid running the softirq at all. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Chris Mason <clm@fb.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: George Spelvin <linux@sciencehorizons.net> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Len Brown <lenb@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: rt@linutronix.de Link: http://lkml.kernel.org/r/20160704094342.607650550@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel/time')
-rw-r--r--kernel/time/timer.c11
1 files changed, 11 insertions, 0 deletions
diff --git a/kernel/time/timer.c b/kernel/time/timer.c
index 9339d71ee998..8d830f1f6a6a 100644
--- a/kernel/time/timer.c
+++ b/kernel/time/timer.c
@@ -1608,7 +1608,18 @@ static void run_timer_softirq(struct softirq_action *h)
*/
void run_local_timers(void)
{
+ struct timer_base *base = this_cpu_ptr(&timer_bases[BASE_STD]);
+
hrtimer_run_queues();
+ /* Raise the softirq only if required. */
+ if (time_before(jiffies, base->clk)) {
+ if (!IS_ENABLED(CONFIG_NO_HZ_COMMON) || !base->nohz_active)
+ return;
+ /* CPU is awake, so check the deferrable base. */
+ base++;
+ if (time_before(jiffies, base->clk))
+ return;
+ }
raise_softirq(TIMER_SOFTIRQ);
}