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Date: Tue, 17 Feb 2004 17:47:55 -0800
From: Andrew Morton <akpm@osdl.org>
To: Daniel McNeil <daniel@osdl.org>
Cc: linux-aio@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2.6.3-rc2-mm1] address_space_serialize_writeback patch
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Daniel McNeil <daniel@osdl.org> wrote:
>
> Here is the patch that does what you suggested.  It adds a rwsema to
> the address_space and do_writepages() uses it serialize writebacks.

Did you verify that we actually _need_ the semaphore?  I seem to recall that
it was a "try this, otherwise add the semaphore" thing.  Where "this" was "always
remark the page dirty".

Probably we do need the semaphore, but I'd just like to check that you checked ;)