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Date: Sat, 11 Jan 2003 08:10:25 +0000
From: Christoph Hellwig <hch@infradead.org>
To: Andrew Morton <akpm@digeo.com>
Cc: Joe Korty <joe.korty@ccur.com>, sct@redhat.com, adilger@clusterfs.com,
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Subject: Re: 2.4.21-pre2 stalls out when running unixbench
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On Sat, Jan 04, 2003 at 03:11:45AM -0800, Andrew Morton wrote:
> Sure, we don't need atomic semantics for the BH_Attached bit because
> it is always read and modified under a global spinlock.  But *other*
> users of buffer_head.b_state do not run under that lock so the nonatomic
> RMW will stomp on their changes.   2.4.20 does not have this bug.

Thanks, I still had to learn something about *_bit() semantics.

And sorry for introducing that bug..

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