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Message-ID: <1335293623.28150.216.camel@twins>
Subject: Re: [PATCH 06/16] sched: SCHED_DEADLINE push and pull logic
From: Peter Zijlstra <peterz@infradead.org>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: Juri Lelli <juri.lelli@gmail.com>, tglx@linutronix.de, mingo@redhat.com,
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Date: Tue, 24 Apr 2012 20:53:43 +0200
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On Tue, 2012-04-24 at 14:50 -0400, Steven Rostedt wrote:
> > Something like so: https://lkml.org/lkml/2012/2/16/487 ?
> 
> But it still does the same thing:
> 
> +static struct task_struct *
> +pick_next_task_rt(struct rq *rq, struct task_struct *prev)
>  {
> -       struct task_struct *p = _pick_next_task_rt(rq);
> +       struct task_struct *p;
> +       struct rt_rq *rt_rq = &rq->rt;
> +
> +       if (!rt_rq->rt_nr_running)
> +               return NULL;
> +
> +       if (rt_rq_throttled(rt_rq))
> +               return NULL;
> +
> +       if (prev)
> +               prev->sched_class->put_prev_task(rq, prev);
> +
> +       p = _pick_next_task_rt(rq);
> 
> Now if we can do the _pick_next_task_rt() before put_prev_task(), and
> only do the put_prev_task() if p != prev, then that would be something.

Well that's up to the implementation of pick_next_task_rt() that
conversion is just a minimal make it work thing.

But the generic changes that patch carries should allow you to do what
you want, right?