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Date: Sat, 2 Nov 2002 01:44:47 -0200 (BRST)
From: Rik van Riel <riel@conectiva.com.br>
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To: Andrew Morton <akpm@digeo.com>
cc: William Lee Irwin III <wli@holomorphy.com>, <linux-kernel@vger.kernel.org>,
       <mingo@elte.hu>, <pbadari@us.ibm.com>
Subject: Re: idle time & iowait accounting
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On Fri, 1 Nov 2002, Andrew Morton wrote:

> > +       preempt_disable();
> > +       rq = this_rq();
> > +       atomic_inc(&rq->nr_iowait);
> > +       schedule();
> > +       atomic_dec(&rq->nr_iowait);
> > +       preempt_enable();

> "scheduling while atomic".

Point.

> You'll need to reacquire the runqueue pointer on waking up.

No. It makes sense to decrement the same counter that was
incremented before.

regards,

Rik
-- 
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