Re: [RFC][PATCH 10/10] sched/eevdf: Use sched_attr::sched_runtime to set request/slice suggestion

From: Peter Zijlstra
Date: Wed May 15 2024 - 06:13:35 EST


On Tue, May 07, 2024 at 07:34:54AM +0200, Mike Galbraith wrote:
> On Fri, 2024-04-05 at 12:28 +0200, Peter Zijlstra wrote:
> >
> > --- a/kernel/sched/core.c
> > +++ b/kernel/sched/core.c
> > @@ -7812,7 +7823,9 @@ static int __sched_setscheduler(struct t
> >          * but store a possible modification of reset_on_fork.
> >          */
> >         if (unlikely(policy == p->policy)) {
> > -               if (fair_policy(policy) && attr->sched_nice != task_nice(p))
> > +               if (fair_policy(policy) &&
> > +                   (attr->sched_nice != task_nice(p) ||
> > +                    (attr->sched_runtime && attr->sched_runtime != p->se.slice)))
> >                         goto change;
>
> Can we make that only look at attr->sched_runtime != p->se.slice?
> Doing so lets you clear a custom slice by.. clearing it.. rather than
> making tools rummage about for the proper value to overwrite.

Duh yes. Seems I already did the right thing in __setscheduler_params()
for that.

Done.