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Date: Mon, 12 Jul 2010 12:04:50 -0400
From: Christoph Hellwig <hch@infradead.org>
Subject: Re: [PATCH] xfs: remove incorrect log write optimization
Message-ID: <20100712160450.GA2666@infradead.org>
References: <20100628143434.GA5473@infradead.org>
	<1278905400.7456.14.camel@doink>
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To: Alex Elder <aelder@sgi.com>
Cc: Christoph Hellwig <hch@infradead.org>, xfs@oss.sgi.com

On Sun, Jul 11, 2010 at 10:30:00PM -0500, Alex Elder wrote:
> On Mon, 2010-06-28 at 10:34 -0400, Christoph Hellwig wrote:
> > We do need a barrier for the first buffer of a split log write.  Otherwise
> > we might incorrectly stamp the tail LSN into transactions in the first
> > block, or not flush data I/O before updating the inode size.
> 
> I'm not sure whether "first block" means the one at the beginning
> of the log, or the one at the beginning of a split log write.

It means beginning of the split write.  I can fix up the commit message
if you want.

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