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Date: Fri, 2 Dec 2011 14:22:54 -0600
From: Dimitri Sivanich <sivanich@sgi.com>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] specific do_timer_cpu value for nohz off mode
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On Fri, Dec 02, 2011 at 02:14:52PM -0600, Dimitri Sivanich wrote:
> So at that time, we could be off +- almost a tick.  The question is, how
> critical is that?  When you down a cpu, the same sort of thing could 
> happen via tick_handover_do_timer(), which itself does nothing more than
> change tick_do_timer_cpu.

I should clarify that by 'same sort of thing' I mean that the target cpu
might've just gone through tick_periodic(), so we could miss a tick before
the next update.