Hi, On 04/08/15 08:41, Peter Zijlstra wrote: > On Mon, Aug 03, 2015 at 07:30:32PM +0200, Frederic Weisbecker wrote: >>> But you've forgotten about SCHED_DEADLINE, we count those in: >>> rq->dl.dl_nr_running. >> >> Indeed. Hmm, there is no preemption between SCHED_DEALINE tasks, right? >> So I can treat it like SCHED_FIFO. > > Sadly no. Even though EDF has static job priority (once a job is > activated its priority doesn't change anymore) DEADLINE also has a CBS > component and that needs the tick regardless, even with a single task. > > So any deadline task running means we cannot stop the tick.
Well, couldn't we stop it when we use hrtick? As start_hrtick_dl() sets the hrtick to fire at tasks runtime depletion instant. Thanks, - Juri > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majord...@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
