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Date: Tue, 15 Apr 2014 12:52:26 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Lists linaro-kernel <linaro-kernel@lists.linaro.org>
Subject: Re: [Query]: tick-sched: why don't we stop tick when we are running
 idle task?
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On Tue, Apr 15, 2014 at 11:30:04AM +0200, Frederic Weisbecker wrote:
> There is probably a few things that assume local calls but last time
> I checked I had the impression that it was fairly possible to call sched_class::task_tick()
> remotely. rq is locked, no reference to "current", use rq accessors...
> 
> OTOH scheduler_tick() itself definetly requires local calls.

possible isn't the problem, its completely insane to do that.