From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH] net: skb_tx_hash() fix relative to skb_orphan_try()
Date: Wed, 14 Jul 2010 15:33:51 -0700 (PDT)
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Tue, 13 Jul 2010 17:24:20 +0200

> commit fc6055a5ba31e2 (net: Introduce skb_orphan_try()) added early
> orphaning of skbs.
> 
> This unfortunately added a performance regression in skb_tx_hash() in
> case of stacked devices (bonding, vlans, ...)
> 
> Since skb->sk is now NULL, we cannot access sk->sk_hash anymore to
> spread tx packets to multiple NIC queues on multiqueue devices.
> 
> skb_tx_hash() in this case only uses skb->protocol, same value for all
> flows.
> 
> skb_orphan_try() can copy sk->sk_hash into skb->rxhash and skb_tx_hash()
> can use this saved sk_hash value to compute its internal hash value.
> 
> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>

Applied, thanks Eric.