tree 15c27522669b08a6d26efbcd447abf3d78ad13fb
parent 3a047bf87b1b6f69c62ab9fb28072c639cb7e2fa
author Eric Dumazet <eric.dumazet@gmail.com> 1278998660 +0000
committer David S. Miller <davem@davemloft.net> 1279146807 -0700

net: skb_tx_hash() fix relative to skb_orphan_try()

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>
Signed-off-by: David S. Miller <davem@davemloft.net>