Re: [GIT PULL] sched_ext: Initial pull request for v6.11

From: Tejun Heo
Date: Tue Aug 06 2024 - 15:56:55 EST


Hello, Peter.

On Wed, Jul 24, 2024 at 10:52:21AM +0200, Peter Zijlstra wrote:
...
> So pick_task() came from the SCHED_CORE crud, which does a remote pick
> and as such isn't able to do a put -- remote is still running its
> current etc.
>
> So pick_task() *SHOULD* already be considering its current and pick
> that if it is a better candidate than whatever is on the queue.
>
> If we have a pick_task() that doesn't do that, it's a pre-existing bug
> and needs fixing anyhow.

I haven't applied the patch to make balance_fair() test
sched_fair_runnable() instead of rq->nr_running yet but after that I think
all review points that you raised should be addressed except for the above
pick_task() conversion. If you want to go ahead with this change, please do
so. I'll pull in tip/sched/core and update accordingly. AFAICS, it doesn't
make any significant difference to SCX one way or the other and I think
updating shouldn't be too painful.

Thanks.

--
tejun