From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: rhashtable: Remove unnecessary wmb for future_tbl
Date: Tue, 08 Dec 2015 22:47:08 -0500 (EST)
Message-ID: <20151208.224708.473911814887888793.davem@davemloft.net>
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From: Herbert Xu <herbert@gondor.apana.org.au>
Date: Tue, 8 Dec 2015 17:09:04 +0800

> The patch 9497df88ab5567daa001829051c5f87161a81ff0 ("rhashtable:
> Fix reader/rehash race") added a pair of barriers.  In fact the
> wmb is superfluous because every subsequent write to the old or
> new hash table uses rcu_assign_pointer, which itself carriers a
> full barrier prior to the assignment.
> 
> Therefore we may remove the explicit wmb.
> 
> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

Applied to net-next.