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Subject: Re: [patch] preempt-timing-on-2.6.8-rc2-O2
From: Lee Revell <rlrevell@joe-job.com>
To: William Lee Irwin III <wli@holomorphy.com>
Cc: Ingo Molnar <mingo@elte.hu>, linux-kernel <linux-kernel@vger.kernel.org>
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On Sat, 2004-08-07 at 22:33, William Lee Irwin III wrote:
> On Sat, Aug 07, 2004 at 10:31:06PM -0400, Lee Revell wrote:
> >  [<c010019f>] 0xc010019f
> > This has to be a false positive, because if there were really ~1ms
> > non-preemptible critical sections all over the place I would be getting
> > xruns.
> 
> This seems to be 996us spent in do_IRQ() when it interrupts idle tasks.
> 

I am not sure I understand how preemption can be disabled for 996us and
not cause an xrun.

Lee