Re: [PATCH 2/3] sched/fair: don't set LBF_ALL_PINNED unnecessarily

[Vincent Guittot]

On Wed, 6 Jan 2021 at 16:32, Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
>
> On Wed, Jan 06, 2021 at 04:20:55PM +0100, Vincent Guittot wrote:
>
> > This case here is :
> > we have 2 tasks TA and TB on the rq.
> > The waiting one TB can't migrate for a reason other than the pinned case.
> > We decide to start the active migration on the running  TA task but TA
> > is pinned.
> > In this case we are not in the all pinned case.
>
> But then can_migrate_task(TB) should clear ALL_PINNED, no?

Yes but current code sets ALL_PINNED when the active migration failed
because the running task is pinned whatever there is not pinned
waiting tasks that has not been selected