Re: [PATCH V7 0/9] SCHED_DEADLINE server infrastructure

[Vineeth Remanan Pillai]

On Mon, Jul 29, 2024 at 6:32 AM Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
>
> On Fri, Jun 21, 2024 at 10:41:35AM -0400, Vineeth Remanan Pillai wrote:
>
> > Sorry that I could not get to reviewing and testing this revision. In
> > v6 we had experienced a minor bug where suspend/resume had issues with
> > dlserver. Since suspend does not do dequeue, dlserver is not stopped
> > and this causes the premature wakeups. I haven't looked at v7 in
> > detail, but I think the issue might still be present.
>
> It is not.
>
> > We have a workaround patch for this in our 5.15 kernel
>
> That is the problem... your necro kernel doesn't yet have the freezer
> rewrite I imagine:
>
>   f5d39b020809 ("freezer,sched: Rewrite core freezer logic")
>
> That would cause all frozen tasks to be dequeued, and once all tasks
> are dequeued, the deadline server stops itself too.
>
You're right, we are on 5.15 kernel and do not have this fix. Thanks
for pointing this out.

> Juri did some testing to double check and no suspend / resume issues
> were found.
>
> Anyway, I've merged the lot into tip/sched/core.
>
Thanks, I shall port it to chromeos kernel and run through the usual
round of tests and update the details soon.

Thanks,
Vineeth