From mboxrd@z Thu Jan  1 00:00:00 1970
From: Simon Horman <horms@verge.net.au>
Subject: Re: [patch] ipvs: Use atomic operations atomicly
Date: Tue, 1 Sep 2009 00:49:09 +1000
Message-ID: <20090831144909.GB2271@verge.net.au>
References: <20090828023722.GA12136@verge.net.au>
 <4A9BC082.3090804@trash.net>
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Cc: lvs-devel@vger.kernel.org, netdev@vger.kernel.org,
	netfilter-devel@vger.kernel.org,
	=?utf-8?B?7ZmN7Iug?= shin hong <hongshin@gmail.com>,
	David Miller <davem@davemloft.net>
To: Patrick McHardy <kaber@trash.net>
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On Mon, Aug 31, 2009 at 02:22:26PM +0200, Patrick McHardy wrote:
> Simon Horman wrote:
> > A pointed out by Shin Hong, IPVS doesn't always use atomic operatio=
ns
> > in an atomic manner. While this seems unlikely to be manifest in
> > strange behaviour, it seems appropriate to clean this up.
> >=20
> > Cc: =ED=99=8D=EC=8B=A0 shin hong <hongshin@gmail.com>
> > Signed-off-by: Simon Horman <horms@verge.net.au>
>=20
> Applied, thanks.
>=20
> >  	if (af =3D=3D AF_INET &&
> >  	    (ip_vs_sync_state & IP_VS_STATE_MASTER) &&
> >  	    (((cp->protocol !=3D IPPROTO_TCP ||
> >  	       cp->state =3D=3D IP_VS_TCP_S_ESTABLISHED) &&
> > -	      (atomic_read(&cp->in_pkts) % sysctl_ip_vs_sync_threshold[1]
> > +	      (pkts % sysctl_ip_vs_sync_threshold[1]
>=20
> It seems that proc_do_sync_threshold() should check whether this valu=
e
> is zero. The current checks also look racy since incorrect values are
> first updated, then overwritten again.

Thanks, I'll look into that.