From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Subject: Re: [PATCH] NFS: Fix RCU warnings in
 nfs_inode_return_delegation_noreclaim() [ver #2]
Date: Mon, 29 Mar 2010 15:36:09 -0700
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Cc: Eric Dumazet <eric.dumazet@gmail.com>, Trond.Myklebust@netapp.com,
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To: David Howells <dhowells@redhat.com>
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On Mon, Mar 29, 2010 at 11:22:30PM +0100, David Howells wrote:
> Paul E. McKenney <paulmck@linux.vnet.ibm.com> wrote:
> 
> > And rcu_dereference_raw() is the same as the old rcu_dereference().
> 
> Exactly.  That's the other half of the issue - that interpolates a redundant
> memory barrier.

Only on Alpha.  Otherwise only a volatile access.

							Thanx, Paul