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Subject: Re: [PATCH] sched: Remove WAKEUP_PREEMPT feature check in
 entity_tick
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Yong Zhang <yong.zhang0@gmail.com>
Cc: Lin Ming <ming.m.lin@intel.com>, "mingo@elte.hu" <mingo@elte.hu>,
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Date: Fri, 29 Jul 2011 10:20:50 +0200
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On Fri, 2011-07-29 at 16:18 +0800, Yong Zhang wrote:
> > Nah, if there is 1 runnable task it will always run, preemption simply
> > doesn't matter. There's nothing to preempt it with.
> 
> Hmmm, so the newly waked task could be scheduled a little later.
> That means schedule tick judge everything. 

Oh, are you referring to the case where a task gets woken on an idle
remote cpu?