Re: [PATCH next] netfilter: nfqueue: batch verdict support

[Patrick McHardy <kaber@trash.net>]

On 03.07.2011 12:24, Eric Dumazet wrote:
> The real question hidden here is : "Should packet ids be monotonic" in
> current implementation and all future ones ?
> 
> Before we accept this patch, we should make sure packets id are
> monotonic, and I am afraid its not the case right now.
> 
> I suggest following patch then.
> 
> [PATCH] netfilter: nfqueue: assert monotonic packet ids
> 
> Packet identifier is currently setup in nfqnl_build_packet_message(),
> using one atomic_inc_return().
> 
> Problem is that since several cpus might concurrently call
> nfqnl_enqueue_packet() for the same queue, we can deliver packets to
> consumer in non monotonic way (packet N+1 being delivered after packet
> N)
> 
> This patch moves the packet id setup from nfqnl_build_packet_message()
> to nfqnl_enqueue_packet() to guarantee correct delivery order.
> 
> This also removes one atomic operation.
> 
> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
> CC: Florian Westphal <fw@strlen.de>
> CC: Pablo Neira Ayuso <pablo@netfilter.org>
> CC: Eric Leblond <eric@regit.org>

Applied, thanks Eric.