Commit-ID: d9f0acdeef48570c4e6159d3108f12b64571392e Gitweb: http://git.kernel.org/tip/d9f0acdeef48570c4e6159d3108f12b64571392e Author: Viresh Kumar <[email protected]> AuthorDate: Tue, 14 Apr 2015 21:08:25 +0000 Committer: Thomas Gleixner <[email protected]> CommitDate: Wed, 22 Apr 2015 17:06:48 +0200
hrtimer: Update active_bases before calling hrtimer_force_reprogram() 'active_bases' indicates which clock-base have active timer. The intention of this bit field was to avoid evaluating inactive bases. It was introduced with the introduction of the BOOTTIME and TAI clock bases, but it was never brought into full use. We want to use it now, but in __remove_hrtimer() the update happens after the calling hrtimer_force_reprogram() which has to evaluate all clock bases for the next expiring timer. So in case the last timer of a clock base got removed we still see the active bit and therefor evaluate the clock base for no value. There are further optimizations possible when active_bases is updated in the right place. Move the update before the call to hrtimer_force_reprogram() [ tglx: Massaged changelog ] Signed-off-by: Viresh Kumar <[email protected]> Reviewed-by: Preeti U Murthy <[email protected]> Acked-by: Peter Zijlstra <[email protected]> Cc: Marcelo Tosatti <[email protected]> Cc: Frederic Weisbecker <[email protected]> Cc: [email protected] Link: http://lkml.kernel.org/r/[email protected] Link: http://lkml.kernel.org/r/c7c8ebcd9ed88bb09d76059c745a1fafb48314e7.1428039899.git.viresh.ku...@linaro.org Signed-off-by: Thomas Gleixner <[email protected]> --- kernel/time/hrtimer.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c index b1a74ee..9abd50b 100644 --- a/kernel/time/hrtimer.c +++ b/kernel/time/hrtimer.c @@ -887,6 +887,9 @@ static void __remove_hrtimer(struct hrtimer *timer, next_timer = timerqueue_getnext(&base->active); timerqueue_del(&base->active, &timer->node); + if (!timerqueue_getnext(&base->active)) + base->cpu_base->active_bases &= ~(1 << base->index); + if (&timer->node == next_timer) { #ifdef CONFIG_HIGH_RES_TIMERS /* Reprogram the clock event device. if enabled */ @@ -900,8 +903,6 @@ static void __remove_hrtimer(struct hrtimer *timer, } #endif } - if (!timerqueue_getnext(&base->active)) - base->cpu_base->active_bases &= ~(1 << base->index); out: timer->state = newstate; } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
