Messages in this thread | | | Date | Tue, 15 May 2018 18:53:04 +0200 | From | Peter Zijlstra <> | Subject | Re: [PATCH 3/3] sched/fair: schedutil: explicit update only when required |
| |
On Tue, May 15, 2018 at 03:53:43PM +0100, Patrick Bellasi wrote: > On 15-May 12:19, Vincent Guittot wrote: > > On 14 May 2018 at 18:32, Patrick Bellasi <patrick.bellasi@arm.com> wrote:
> > Yes se becomes NULL only when you reach root domain
root group; domains are something else again ;-)
> Thus, the scheduler knows that we are going to sleep: does is really > makes sense to send a notification in this case?
It might; esp. on these very slow changing machines.
> What about adding a new explicit callback at the end of: > update_blocked_averages() ? > > Something like: > > ---8<--- > diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c > index cb77407ba485..6eb0f31c656d 100644 > --- a/kernel/sched/fair.c > +++ b/kernel/sched/fair.c > @@ -7740,6 +7740,9 @@ static void update_blocked_averages(int cpu) > if (done) > rq->has_blocked_load = 0; > #endif > + > + cpufreq_update_util(rq, SCHED_CPUFREQ_IDLE); > + > rq_unlock_irqrestore(rq, &rf); > } > ---8<--- > > Where we can also pass in a new SCHED_CPUFREQ_IDLE flag just to notify > schedutil that the CPU is currently IDLE? > > Could that work?
Simlarly you could add ENQUEUE/DEQUEUE flags I suppose. But let's do all that later in separate patches and evaluate the impact separately, OK?
| |