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Date: Thu, 25 Sep 2008 00:43:37 +0100 (BST)
From: Hugh Dickins <hugh@veritas.com>
X-X-Sender: hugh@blonde.site
To: David Howells <dhowells@redhat.com>
cc: Matt Mackall <mpm@selenic.com>, Nick Piggin <npiggin@suse.de>,
       Dave Hansen <dave@linux.vnet.ibm.com>,
       Jeremy Fitzhardinge <jeremy@goop.org>, Ingo Molnar <mingo@elte.hu>,
       Andrew Morton <akpm@linux-foundation.org>, a.p.zijlstra@chello.nl,
       linux-kernel@vger.kernel.org, Dave Hansen <haveblue@us.ibm.com>
Subject: Re: [patch] mm: tiny-shmem fix lor, mmap_sem vs i_mutex
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On Wed, 24 Sep 2008, David Howells wrote:
> Hugh Dickins <hugh@veritas.com> wrote:
> 
> > If we're hell-bent on #ifdefs throughout mm/shmem.c, I wouldn't
> > mind scattering some CONFIG_SWAPs in there too, would cut out
> > lots of overhead when swap unconfigured.  But again, how ugly?
> 
> That might be necessary: NOMMU doesn't support swap.

Matt would be dealing with that aspect in his unification: SHMEM
depends on MMU, so !MMU gives you TINY_SHMEM - I'm sure he wouldn't
have any of the SWAP stuff in the TINY_SHMEM part of his unification.
But there's still value in adding CONFIG_SWAPs too (if the #ifdefs
were tolerable, by no means clear).

Hugh