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

Mike Galbraith
2024-05-07T05:35:40Z

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.

-Mike