Commit-ID: 92a801e5d5b7a893881c1676b15dd246727ccd16 Gitweb: https://git.kernel.org/tip/92a801e5d5b7a893881c1676b15dd246727ccd16 Author: Patrick Bellasi <patrick.bell...@arm.com> AuthorDate: Mon, 5 Nov 2018 14:53:59 +0000 Committer: Ingo Molnar <mi...@kernel.org> CommitDate: Mon, 12 Nov 2018 06:17:52 +0100
sched/fair: Mask UTIL_AVG_UNCHANGED usages The _task_util_est() is mainly used to add/remove the task contribution to/from the rq's estimated utilization at task enqueue/dequeue time. In both cases we ensure the UTIL_AVG_UNCHANGED flag is set to keep consistency between enqueue and dequeue time while still being transparent to update_load_avg calls which will eventually reset the flag. Let's move the flag forcing within _task_util_est() itself so that we can simplify calling code by hiding that estimated utilization implementation detail into one of its internal functions. This will affect also the "public" API task_util_est() but we know that the flag will (eventually) impact just on the LSB of the estimated utilization, thus it's certainly acceptable. Signed-off-by: Patrick Bellasi <patrick.bell...@arm.com> Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org> Cc: Dietmar Eggemann <dietmar.eggem...@arm.com> Cc: Juri Lelli <juri.le...@redhat.com> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Morten Rasmussen <morten.rasmus...@arm.com> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Quentin Perret <quentin.per...@arm.com> Cc: Steve Muckle <smuc...@google.com> Cc: Suren Baghdasaryan <sur...@google.com> Cc: Thomas Gleixner <t...@linutronix.de> Cc: Todd Kjos <tk...@google.com> Cc: Vincent Guittot <vincent.guit...@linaro.org> Link: http://lkml.kernel.org/r/20181105145400.935-3-patrick.bell...@arm.com Signed-off-by: Ingo Molnar <mi...@kernel.org> --- kernel/sched/fair.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index a1ccf1ddd37a..28ee60cabba1 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -3604,7 +3604,7 @@ static inline unsigned long _task_util_est(struct task_struct *p) { struct util_est ue = READ_ONCE(p->se.avg.util_est); - return max(ue.ewma, ue.enqueued); + return (max(ue.ewma, ue.enqueued) | UTIL_AVG_UNCHANGED); } static inline unsigned long task_util_est(struct task_struct *p) @@ -3622,7 +3622,7 @@ static inline void util_est_enqueue(struct cfs_rq *cfs_rq, /* Update root cfs_rq's estimated utilization */ enqueued = cfs_rq->avg.util_est.enqueued; - enqueued += (_task_util_est(p) | UTIL_AVG_UNCHANGED); + enqueued += _task_util_est(p); WRITE_ONCE(cfs_rq->avg.util_est.enqueued, enqueued); } @@ -3650,8 +3650,7 @@ util_est_dequeue(struct cfs_rq *cfs_rq, struct task_struct *p, bool task_sleep) /* Update root cfs_rq's estimated utilization */ ue.enqueued = cfs_rq->avg.util_est.enqueued; - ue.enqueued -= min_t(unsigned int, ue.enqueued, - (_task_util_est(p) | UTIL_AVG_UNCHANGED)); + ue.enqueued -= min_t(unsigned int, ue.enqueued, _task_util_est(p)); WRITE_ONCE(cfs_rq->avg.util_est.enqueued, ue.enqueued); /* @@ -6292,7 +6291,7 @@ static unsigned long cpu_util_without(int cpu, struct task_struct *p) */ if (unlikely(task_on_rq_queued(p) || current == p)) { estimated -= min_t(unsigned int, estimated, - (_task_util_est(p) | UTIL_AVG_UNCHANGED)); + _task_util_est(p)); } util = max(util, estimated); }
