Re: [PATCH 1/6] sched/ext: Fix scx vs sched_delayed

[Peter Zijlstra]

On Wed, Oct 30, 2024 at 03:50:05PM +0000, Christian Loehle wrote:
> On 10/30/24 15:12, Peter Zijlstra wrote:
> > Commit 98442f0ccd82 ("sched: Fix delayed_dequeue vs
> > switched_from_fair()") forgot about scx :/
> > 
> > Fixes: 98442f0ccd82 ("sched: Fix delayed_dequeue vs switched_from_fair()")
> > Reported-by: Tejun Heo <tj@xxxxxxxxxx>
> > Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
> > Link: https://lkml.kernel.org/r/20241030104934.GK14555@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
> > ---
> >  kernel/sched/ext.c |   14 ++++++++++++--
> >  1 file changed, 12 insertions(+), 2 deletions(-)
> > 
> > --- a/kernel/sched/ext.c
> > +++ b/kernel/sched/ext.c
> > @@ -4489,11 +4489,16 @@ static void scx_ops_disable_workfn(struc
> >  	scx_task_iter_start(&sti);
> >  	while ((p = scx_task_iter_next_locked(&sti))) {
> >  		const struct sched_class *old_class = p->sched_class;
> > +		const struct sched_class *new_class =
> > +			__setscheduler_class(p->policy, p->prio);
> >  		struct sched_enq_and_set_ctx ctx;
> >  
> > +		if (old_class != new_class && p->se.sched_delayed)
> > +			dequeue_task(task_rq(p), p, DEQUEUE_SLEEP | DEQUEUE_DELAYED);
> > +
> >  		sched_deq_and_put_task(p, DEQUEUE_SAVE | DEQUEUE_MOVE, &ctx);
> >  
> > -		p->sched_class = __setscheduler_class(p->policy, p->prio);
> > +		p->sched_class = new_class;
> >  		check_class_changing(task_rq(p), p, old_class);
> >  
> >  		sched_enq_and_set_task(&ctx);
> > @@ -5199,12 +5204,17 @@ static int scx_ops_enable(struct sched_e
> >  	scx_task_iter_start(&sti);
> >  	while ((p = scx_task_iter_next_locked(&sti))) {
> >  		const struct sched_class *old_class = p->sched_class;
> > +		const struct sched_class *new_class =
> > +			__setscheduler_class(p->policy, p->prio);
> >  		struct sched_enq_and_set_ctx ctx;
> >  
> > +		if (old_class != new_class && p->se.sched_delayed)
> > +			dequeue_task(task_rq(p), p, DEQUEUE_SLEEP | DEQUEE_DELAYED);
> > +
> 
> s/DEQUEE_DELAYED/DEQUEUE_DELAYED

Bah, typing so hard..

> Anyway, no luck for me applying the series onto sched/core scx's for-next or rc5.
> Any hint or do you mind supplying a branch?

I think I did it on top of tip/master..