From: Thomas Graf <tgraf@suug.ch>
To: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "David S. Miller" <davem@davemloft.net>,
Eric Dumazet <eric.dumazet@gmail.com>,
Josh Triplett <josh@joshtriplett.org>,
"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
netdev@vger.kernel.org
Subject: Re: rhashtable: Remove unnecessary wmb for future_tbl
Date: Wed, 9 Dec 2015 03:52:12 +0100 [thread overview]
Message-ID: <20151209025212.GB20213@pox.localdomain> (raw)
In-Reply-To: <20151208090904.GA17605@gondor.apana.org.au>
On 12/08/15 at 05:09pm, Herbert Xu wrote:
> 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>
The RELEASE which is now in place afterwards act as a wmb as well,
we are well protected ;-)
Acked-by: Thomas Graf <tgraf@suug.ch>
next prev parent reply other threads:[~2015-12-09 2:52 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-12-08 9:09 rhashtable: Remove unnecessary wmb for future_tbl Herbert Xu
2015-12-09 2:52 ` Thomas Graf [this message]
2015-12-09 3:47 ` David Miller
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