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Subject: Re: [PATCH] sched: avoid unnecessary overflow in sched_clock
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Paul Turner <pjt@google.com>
Cc: Mike Galbraith <efault@gmx.de>, john stultz <johnstul@us.ibm.com>,
        Salman Qazi <sqazi@google.com>, Ingo Molnar <mingo@elte.hu>,
        LKML <linux-kernel@vger.kernel.org>
Date: Wed, 16 Nov 2011 09:56:22 +0100
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On Tue, 2011-11-15 at 23:08 -0800, Paul Turner wrote:
> Probably a good idea -- This especially sucks rocks in the sched_clock_stable==1 
> case; resulting in it coming straight back out of sched_clock_cpu() and trashing 
> rq->clock. 

There's another problem there in that TSC will wrap too soon and things
will blow up in your face that way.