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Message-ID: <1370215895.24311.93.camel@edumazet-glaptop>
Subject: Re: [PATCH v2] rcu: fix a race in hlist_nulls_for_each_entry_rcu
 macro
From: Eric Dumazet <eric.dumazet@gmail.com>
To: Roman Gushchin <klamm@yandex-team.ru>
Cc: David Miller <davem@davemloft.net>, paulmck@linux.vnet.ibm.com,
        Jesper Dangaard Brouer <brouer@redhat.com>,
        Dipankar Sarma <dipankar@in.ibm.com>, zhmurov@yandex-team.ru,
        linux-kernel@vger.kernel.org, netdev@vger.kernel.org,
        Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>,
        James Morris <jmorris@namei.org>,
        Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>,
        Patrick McHardy <kaber@trash.net>,
        David Laight <David.Laight@ACULAB.COM>
Date: Sun, 02 Jun 2013 16:31:35 -0700
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On Thu, 2013-05-30 at 12:25 +0400, Roman Gushchin wrote:
> On 29.05.2013 23:06, Eric Dumazet wrote:
> > On Wed, 2013-05-29 at 14:09 +0400, Roman Gushchin wrote:
> >
> > True, these lookup functions are usually structured the same around the
> > hlist_nulls_for_each_entry_rcu() loop.
> >
> > A barrier() right before the loop seems to be a benefit, the size of
> > assembly code is reduced by 48 bytes.
> >
> > And its one of the documented way to handle this kind of problems
> > (Documentation/atomic_ops.txt line 114)
> >
> > I guess we should amend this documentation, eventually.
> >
> > Thanks, please add you "Signed-off-by" if you agree with the patch.
> >
> 
> Signed-off-by: Roman Gushchin <klamm@yandex-team.ru>
> 
> Many thanks to you, Paul E. McKenney and David Laight for your
> patches, help and participation in this discussion.

Thanks to you !

David, is there any problem with the patch ?

http://patchwork.ozlabs.org/patch/247360/ says "Not applicable", please
tell me what is needed to get it merged.

Thanks !