On Fri, Jan 17, 2014 at 04:06:45PM +0100, Daniel Lezcano wrote:
> >I suppose we could write something like:
> >
> >struct task_struct *pick_next_task(struct rq *rq, struct task_struct *prev)
> >{
> >     const struct sched_class *class;
> >     struct task_struct *p;
> >
> >again:
> >     if (likely(rq->nr_running)) {
> >
> >             if (likely(rq->nr_running == rq->cfs.h_nr_running))
> >                     return fair_sched_class.pick_next_task(rq, prev);
> >
> >             for_each_class(class) {
> >                     p = class->pick_next_task(rq, prev);
> >                     if (p)
> >                             return p;
> >             }
> >     }
> >
> >     if (idle_balance(rq))
> >             goto again;
> >
> >     rq->idle_stamp = rq_clock(rq);
> >
> >     return idle_sched_class.pick_next_task(rq, prev);
> >}
> >
> >Which keeps idle_balance() before put_prev_task(), and by using
> >idle_sched_clas.pick_next_task() doesn't rape the idle class interface
> >like you did :-)
> 
> But put_prev_task is called before pick_next_task, so idle_balance() is
> called after now, no  ?

No, put_prev_task() is called by the pick_next_task() that returns a
task. So in the idle case above, the idle_sched_class.pick_next_task()
will do the required put_prev_task().
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to