Re: [PATCH v8 1/2] sched/deadline: Add support for SD_PREFER_SIBLING on find_later_rq()

From: Byungchul Park
Date: Tue Aug 22 2017 - 01:55:47 EST


On Mon, Aug 21, 2017 at 03:07:57PM +0100, Juri Lelli wrote:
> > Consider a 4 core, SMT2 system:
> >
> > LLC [0 - 7]
> >
> > SMT [0,1] [2,3] [4,5] [6,7]
> >
> > If we do a wake-up on CPU0, we'll find CPU1, mark that as fallback,
> > continue up the domain tree, exclude 0,1 from 0-7 and find CPU2.
> >
> > A next wakeup on CPU0 does the same and will find CPU3, fully loading
> > that core, instead of considering CPU4 first.
> >
>
> Ah, right, I see. Thanks for explaining.
>
> Byungchul, maybe you could add this explanation as a comment?

Yes. Good idea. I will add it.

Thank you,
Byungchul