Re: [PATCH 2/2] sched: Don't report SCHED_FLAG_SUGOV in sched_getattr()

From: Quentin Perret
Date: Thu Jul 29 2021 - 13:28:20 EST


On Thursday 29 Jul 2021 at 19:21:03 (+0200), Dietmar Eggemann wrote:
> On 28/07/2021 14:36, Juri Lelli wrote:
> > On 28/07/21 10:39, Quentin Perret wrote:
> >> On Wednesday 28 Jul 2021 at 11:12:03 (+0200), Juri Lelli wrote:
>
> [...]
>
> >>> Maybe we can do this in the previous patch so that it's kept confined to
> >>> deadline bits?
> >>
> >> That works too, it just felt like this could happen again if we start
> >> using non-standard flags outside of deadline for any reason at some
> >> point in the future. But no strong opinion really.
> >
> > Yeah, I also see this point. :)
> >
> > So no prob with me to keep it in core.c as you do here.
> >
> > Best,
> > Juri
> >
>
> I would vote for not exporting SCHED_FLAG_SUGOV from __getparam_dl() in
> patch 1/2 to underpin the idea that this flag is a hack.
>
> @ -2759,7 +2759,7 @@ void __getparam_dl(struct task_struct *p, struct
> sched_attr *attr)
> attr->sched_deadline = dl_se->dl_deadline;
> attr->sched_period = dl_se->dl_period;
> attr->sched_flags &= ~SCHED_DL_FLAGS;
> - attr->sched_flags |= dl_se->flags;
> + attr->sched_flags |= dl_se->flags & ~SCHED_FLAG_SUGOV;

Alright, that's 2 votes against 1, you win!
I'll post a v2 shortly.

Cheers,
Quentin