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Date: Mon, 10 May 2010 19:43:29 -0400
From: Andrew Morton <akpm@linux-foundation.org>
To: Arjan van de Ven <arjan@infradead.org>
Cc: linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/2] cpuidle: Add a repeating pattern detector to the
 menu governor
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On Mon, 10 May 2010 18:27:46 -0700 Arjan van de Ven <arjan@infradead.org> wrote:

> On Mon, 10 May 2010 14:38:50 -0700
> Andrew Morton <akpm@linux-foundation.org> wrote:
> 
> > > +	if (avg && stddev < STDDEV_THRESH)
> > > +		data->predicted_us = avg;
> > > +}
> > 
> > You got lucky there, because INTERVALS is a power of two.  If someone
> > changes INTERVALS to 7, this code will ask for __udivdi3 and won't
> > link on i364.
> 
> yeah you'd think it almost isn't an accident ;-)

If it was deliberate the code would read

	avg >>= INTERVALS_SHIFT;

:-p