Re: [RFC v2 1/7] Track the active utilisation

From: Peter Zijlstra
Date: Tue Apr 05 2016 - 08:23:38 EST


On Fri, Apr 01, 2016 at 05:12:27PM +0200, Luca Abeni wrote:
> @@ -1210,6 +1232,8 @@ static void task_fork_dl(struct task_struct *p)
> static void task_dead_dl(struct task_struct *p)
> {
> struct dl_bw *dl_b = dl_bw_of(task_cpu(p));
> + struct dl_rq *dl_rq = dl_rq_of_se(&p->dl);
> + struct rq *rq = rq_of_dl_rq(dl_rq);
>
> /*
> * Since we are TASK_DEAD we won't slip out of the domain!
> @@ -1218,6 +1242,9 @@ static void task_dead_dl(struct task_struct *p)
> /* XXX we should retain the bw until 0-lag */
> dl_b->total_bw -= p->dl.dl_bw;
> raw_spin_unlock_irq(&dl_b->lock);
> +
> + if (task_on_rq_queued(p))
> + sub_running_bw(&p->dl, &rq->dl);
> }
>

A dead task cannot be running, not be queued, right? ISTR you remove
this hunk in a later patch as well.