diff options
author | Thomas Gleixner <tglx@linutronix.de> | 2016-07-04 09:50:37 (GMT) |
---|---|---|
committer | Ingo Molnar <mingo@kernel.org> | 2016-07-07 08:35:11 (GMT) |
commit | 4e85876a9d2a977b4a07389da8c07edf76d10825 (patch) | |
tree | 4e0d4f1ba711f1c737309211a4c097c4ac994b94 | |
parent | a683f390b93f4d1292f849fc48d28e322046120f (diff) | |
download | linux-4e85876a9d2a977b4a07389da8c07edf76d10825.tar.xz |
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>
-rw-r--r-- | kernel/time/timer.c | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/kernel/time/timer.c b/kernel/time/timer.c index 9339d71..8d830f1 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); } |