From: David Howells <dhowells@redhat.com>
To: paulmck@linux.vnet.ibm.com
Cc: dhowells@redhat.com, Eric Dumazet <eric.dumazet@gmail.com>,
Trond.Myklebust@netapp.com, linux-nfs@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH] NFS: Fix RCU warnings in nfs_inode_return_delegation_noreclaim() [ver #2]
Date: Wed, 31 Mar 2010 18:37:34 +0100 [thread overview]
Message-ID: <15371.1270057054@redhat.com> (raw)
In-Reply-To: <20100331151604.GC2461@linux.vnet.ibm.com>
Paul E. McKenney <paulmck@linux.vnet.ibm.com> wrote:
> Protected by something that the caller did, be it holding the the correct
> lock, operating on it during initialization before other CPUs have access
> to it, operating on it during cleanup after other CPUs' access has been
> revoked, or whatever.
But the point I made very early this morning still stands: What if someone
simply wants to test the pointer, not actually to dereference it?
NFS was using rcu_dereference() for this in a couple of places - which is
overkill. I suggested stripping this off and you countered with the
suggestion that it should be using rcu_dereference_check().
Why do I need anything at all?
David
next prev parent reply other threads:[~2010-03-31 17:37 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-03-18 13:33 [PATCH] NFS: Fix RCU warnings in nfs_inode_return_delegation_noreclaim() [ver #2] David Howells
2010-03-19 2:25 ` Paul E. McKenney
2010-03-29 19:02 ` David Howells
2010-03-29 19:21 ` Paul E. McKenney
2010-03-29 20:15 ` David Howells
2010-03-29 20:26 ` Eric Dumazet
2010-03-29 21:05 ` Paul E. McKenney
2010-03-29 22:22 ` David Howells
2010-03-29 22:36 ` Paul E. McKenney
2010-03-29 22:59 ` David Howells
2010-03-29 23:26 ` Paul E. McKenney
2010-03-30 15:40 ` Paul E. McKenney
2010-03-30 16:39 ` David Howells
2010-03-30 16:49 ` Paul E. McKenney
2010-03-30 17:04 ` Eric Dumazet
2010-03-30 17:25 ` Paul E. McKenney
2010-03-30 23:51 ` David Howells
2010-03-31 0:08 ` Paul E. McKenney
2010-03-31 14:04 ` David Howells
2010-03-31 15:16 ` Paul E. McKenney
2010-03-31 17:37 ` David Howells [this message]
2010-03-31 18:30 ` Paul E. McKenney
2010-03-31 18:32 ` Eric Dumazet
2010-03-31 22:53 ` David Howells
2010-04-01 1:29 ` Paul E. McKenney
2010-04-01 11:45 ` David Howells
2010-04-01 14:39 ` Paul E. McKenney
2010-04-01 14:46 ` David Howells
2010-04-05 17:57 ` Paul E. McKenney
2010-04-06 9:30 ` David Howells
2010-04-06 16:14 ` David Howells
2010-04-06 17:29 ` Paul E. McKenney
2010-04-06 19:34 ` David Howells
2010-04-07 0:02 ` Paul E. McKenney
2010-04-07 13:22 ` David Howells
2010-04-07 15:57 ` Paul E. McKenney
2010-04-07 16:35 ` RCU condition checks David Howells
2010-04-07 17:10 ` Paul E. McKenney
2010-04-11 22:57 ` Trond Myklebust
2010-04-12 16:47 ` Paul E. McKenney
2010-03-30 16:37 ` [PATCH] NFS: Fix RCU warnings in nfs_inode_return_delegation_noreclaim() [ver #2] David Howells
2010-03-30 17:01 ` Paul E. McKenney
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