On Thu, Feb 23, 2017 at 10:07 PM, Peter Zijlstra <pet...@infradead.org> wrote: > On Thu, Feb 23, 2017 at 04:25:33PM +0100, Peter Zijlstra wrote: >> >> Ah, I read your question wrong. Yes I think you're right, we now loose >> the pull when the last RT task goes away. >> >> Hmm.. how to fix that nicely.. > > Something like so perhaps? This would make a pull happen when the last > RT task on this CPU goes away. > > Steve? > > --- > diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c > index 9f3e40226dec..283d591078b0 100644 > --- a/kernel/sched/rt.c > +++ b/kernel/sched/rt.c > @@ -1336,6 +1336,9 @@ static void dequeue_task_rt(struct rq *rq, struct > task_struct *p, int flags) > dequeue_rt_entity(rt_se, flags); > > dequeue_pushable_task(rq, p); > + > + if (!rq->rt.rt_nr_running) > + queue_pull_task(rq); > } > > /*
The next balance_callback() is not called until the context switch is completed. So we potentially pick a lower class task before the pull happens. Would it be wrong to call pull_rt_task() directly instead of queuing the callback. -- Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center, Inc. Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project
