Re: [RFC][PATCH 0/3] sched: User Managed Concurrency Groups

[Peter Oskolkov]

On Tue, Dec 14, 2021 at 12:55 PM Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
>
> Hi,
>
> This is actually tested code; but still missing the SMP wake-to-idle machinery.
> I still need to think about that.

Thanks, Peter!

At a first glance, your main patch does not look much smaller than
mine, and I thought the whole point of re-doing it was to throw away
extra features and make things smaller/simpler...

Anyway, I'll test your patchset over the next week or so and let you
know if anything really needed is missing (other than waking an idle
server if there is one on a worker wakeup; this piece is definitely
needed).

>
> I'll post my test-hack as a reply, but basically it does co-operative and
> preemptive UP-like user scheduling.
>
> Patches go on top of tip/master as they rely on the .fixup removal
> recently merged in tip/x86/core.
>
> Also, I still need to audit a bunch of mm code, because I'm not sure things are
> actually as well behaved as this code supposes they are.
>