Re: [patch 08/18] sched: add support for throttling group entities

Lin Ming
2011-08-08T15:46:17Z

On Fri, Jul 22, 2011 at 12:43 AM, Paul Turner <pjt@google.com> wrote:

> +static __used void throttle_cfs_rq(struct cfs_rq *cfs_rq)
> +{
> +       struct rq *rq = rq_of(cfs_rq);
> +       struct cfs_bandwidth *cfs_b = tg_cfs_bandwidth(cfs_rq->tg);
> +       struct sched_entity *se;
> +       long task_delta, dequeue = 1;
> +
> +       se = cfs_rq->tg->se[cpu_of(rq_of(cfs_rq))];
> +
> +       /* account load preceding throttle */
> +       update_cfs_load(cfs_rq, 0);
> +
> +       task_delta = cfs_rq->h_nr_running;
> +       for_each_sched_entity(se) {
> +               struct cfs_rq *qcfs_rq = cfs_rq_of(se);
> +               /* throttled entity or throttle-on-deactivate */
> +               if (!se->on_rq)
> +                       break;

Does it mean it's possible that child se is unthrottled but parent se
is throttled?

I thought if parent group was throttled then its children should be
throttled too.
I may misunderstood the code, please correct me then.

Thanks,
Lin Ming