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Message-ID: <84144f020805072230g2a619d65x8e3bb1fbf9d130d8@mail.gmail.com>
Date: Thu, 8 May 2008 08:30:20 +0300
From: "Pekka Enberg" <penberg@cs.helsinki.fi>
To: "Andrea Arcangeli" <andrea@qumranet.com>
Subject: Re: [PATCH 08 of 11] anon-vma-rwsem
Cc: "Linus Torvalds" <torvalds@linux-foundation.org>,
       "Christoph Lameter" <clameter@sgi.com>,
       "Andrew Morton" <akpm@linux-foundation.org>, steiner@sgi.com,
       holt@sgi.com, npiggin@suse.de, a.p.zijlstra@chello.nl,
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On Thu, May 8, 2008 at 8:27 AM, Pekka Enberg <penberg@cs.helsinki.fi> wrote:
> You might want to read carefully what Linus wrote:
>
>  > The one that already has a 4 byte padding thing on x86-64 just after the
>  > spinlock? And that on 32-bit x86 (with less than 256 CPU's) would have two
>  > bytes of padding if we didn't just make the spinlock type unconditionally
>  > 32 bits rather than the 16 bits we actually _use_?
>
>  So you need to add the flag _after_ ->lock and _before_ ->head....

Oh should have taken my morning coffee first, before ->lock works
obviously as well.