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Date:   Sun, 10 Jul 2022 22:16:01 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Dave Chinner <david@fromorbit.com>
Cc:     "Darrick J. Wong" <djwong@kernel.org>, linux-xfs@vger.kernel.org
Subject: Re: [PATCH 6/6] xfs: lockless buffer lookup
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On Thu, Jul 07, 2022 at 10:36:33PM +1000, Dave Chinner wrote:
> > 
> > Hmm, so what still uses pag_buf_lock?  Are we still using it to
> > serialize xfs_buf_rele calls?
> 
> slow path lookup/insert and xfs_buf_rele calls.

Note that we might be able to eventually remove the locking in rele
if we switch the lookup slow path to use atomic_inc_unless_zero as
well.  But it would need a very careful audit.