Re: [PATCH v2 5/7] sched: Implement shared runqueue in CFS

[Aaron Lu]

On Mon, Jul 10, 2023 at 03:03:40PM -0500, David Vernet wrote:
>  static void shared_runq_dequeue_task(struct task_struct *p)
> -{}
> +{
> +	unsigned long flags;
> +	struct shared_runq *shared_runq;
> +
> +	if (!list_empty(&p->shared_runq_node)) {
> +		shared_runq = rq_shared_runq(task_rq(p));
> +		spin_lock_irqsave(&shared_runq->lock, flags);

After taking the lock, p may have been poped by another newidle cpu.
Running list_del_init() doesn't seem hurt, but is this intended?

> +		list_del_init(&p->shared_runq_node);
> +		spin_unlock_irqrestore(&shared_runq->lock, flags);
> +	}
> +}