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Date: Sun, 6 May 2001 22:19:38 -0700
From: Aaron Lehmann <aaronl@vitelus.com>
To: "David S. Miller" <davem@redhat.com>
Cc: Jonathan Morton <chromi@cyberspace.org>,
        BERECZ Szabolcs <szabi@inf.elte.hu>, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org
Subject: Re: page_launder() bug
Message-ID: <20010506221938.A29493@vitelus.com>
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In-Reply-To: <15094.10942.592911.70443@pizda.ninka.net>; from davem@redhat.com on Sun, May 06, 2001 at 09:55:26PM -0700
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On Sun, May 06, 2001 at 09:55:26PM -0700, David S. Miller wrote:
> 
> Jonathan Morton writes:
>  > >-			 page_count(page) == (1 + !!page->buffers));
>  > Two inversions in a row?
> It is the most straightforward way to make a '1' or '0'
> integer from the NULL state of a pointer.

page_count(page) == (1 + (page->buffers != 0));