Commit-ID: 41e0d37f7ac81297c07ba311e4ad39465b8c8295 Gitweb: http://git.kernel.org/tip/41e0d37f7ac81297c07ba311e4ad39465b8c8295 Author: Steve Muckle <steve.muc...@linaro.org> AuthorDate: Mon, 21 Mar 2016 17:21:08 -0700 Committer: Ingo Molnar <mi...@kernel.org> CommitDate: Sat, 23 Apr 2016 14:20:36 +0200
sched/fair: Do not call cpufreq hook unless util changed There's no reason to call the cpufreq hook if the root cfs_rq utilization has not been modified. Signed-off-by: Steve Muckle <smuc...@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org> Cc: Dietmar Eggemann <dietmar.eggem...@arm.com> Cc: Juri Lelli <juri.le...@arm.com> Cc: Michael Turquette <mturque...@baylibre.com> Cc: Mike Galbraith <efa...@gmx.de> Cc: Morten Rasmussen <morten.rasmus...@arm.com> Cc: Patrick Bellasi <patrick.bell...@arm.com> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Rafael J. Wysocki <raf...@kernel.org> Cc: Thomas Gleixner <t...@linutronix.de> Cc: Vincent Guittot <vincent.guit...@linaro.org> Link: http://lkml.kernel.org/r/1458606068-7476-2-git-send-email-smuc...@linaro.org Signed-off-by: Ingo Molnar <mi...@kernel.org> --- kernel/sched/fair.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 6df80d4..8155281 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -2879,20 +2879,21 @@ static inline int update_cfs_rq_load_avg(u64 now, struct cfs_rq *cfs_rq) { struct sched_avg *sa = &cfs_rq->avg; struct rq *rq = rq_of(cfs_rq); - int decayed, removed = 0; + int decayed, removed_load = 0, removed_util = 0; int cpu = cpu_of(rq); if (atomic_long_read(&cfs_rq->removed_load_avg)) { s64 r = atomic_long_xchg(&cfs_rq->removed_load_avg, 0); sa->load_avg = max_t(long, sa->load_avg - r, 0); sa->load_sum = max_t(s64, sa->load_sum - r * LOAD_AVG_MAX, 0); - removed = 1; + removed_load = 1; } if (atomic_long_read(&cfs_rq->removed_util_avg)) { long r = atomic_long_xchg(&cfs_rq->removed_util_avg, 0); sa->util_avg = max_t(long, sa->util_avg - r, 0); sa->util_sum = max_t(s32, sa->util_sum - r * LOAD_AVG_MAX, 0); + removed_util = 1; } decayed = __update_load_avg(now, cpu, sa, @@ -2903,7 +2904,8 @@ static inline int update_cfs_rq_load_avg(u64 now, struct cfs_rq *cfs_rq) cfs_rq->load_last_update_time_copy = sa->last_update_time; #endif - if (cpu == smp_processor_id() && &rq->cfs == cfs_rq) { + if (cpu == smp_processor_id() && &rq->cfs == cfs_rq && + (decayed || removed_util)) { unsigned long max = rq->cpu_capacity_orig; /* @@ -2926,7 +2928,7 @@ static inline int update_cfs_rq_load_avg(u64 now, struct cfs_rq *cfs_rq) min(sa->util_avg, max), max); } - return decayed || removed; + return decayed || removed_load; } /* Update task and its cfs_rq load average */
