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Date: Sun, 5 Jul 2009 22:31:13 -0400
From: Theodore Tso <tytso@mit.edu>
To: Jesper Dangaard Brouer <hawk@comx.dk>
Cc: "David S. Miller" <davem@davemloft.net>,
       "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>, netdev@vger.kernel.org,
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Subject: Re: [PATCH 01/10] ext4: Use rcu_barrier() on module unload.
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On Tue, Jun 23, 2009 at 05:03:59PM +0200, Jesper Dangaard Brouer wrote:
> The ext4 module uses rcu_call() thus it should use rcu_barrier()on
> module unload.
> 
> The kmem cache ext4_pspace_cachep is sometimes free'ed using
> call_rcu() callbacks.  Thus, we must wait for completion of call_rcu()
> before doing kmem_cache_destroy().
> 
> I have difficult determining if no new call_rcu() callbacks can be envoked.
> Would the maintainer please verify this?

Yes, that's correct.  Thanks; I've included this in the ext4 patch
queue.

						- Ted
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