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Message-ID: <1323806736.28489.0.camel@twins>
Subject: Re: [PATCH] include/log2.h: Fix rounddown_pow_of_two(1)
From: Peter Zijlstra <peterz@infradead.org>
To: Dmitry Torokhov <dtor@vmware.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
        linux-kernel@vger.kernel.org,
        Andrew Morton <akpm@linux-foundation.org>, pv-drivers@vmware.com,
        Andrei Warkentin <andreiw@vmware.com>, stable@kernel.org
Date: Tue, 13 Dec 2011 21:05:36 +0100
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On Tue, 2011-12-13 at 21:00 +0100, Peter Zijlstra wrote:
> On Mon, 2011-12-12 at 10:02 -0800, Dmitry Torokhov wrote:
> > 1 is a power of two, therefore rounddown_pow_of_two(1) should return 1.
> 
> x^0 = 1
> x^1 = x
> 
> Seems to me 0 was the right answer, no?

n/m head-up-arse, missed that this wasn't actually a log variant.