From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH v2] netdev:bfin_mac: reclaim and free tx skb as soon as
 possible after transfer
Date: Mon, 07 Jun 2010 11:58:00 +0200
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Cc: David Miller <davem@davemloft.net>,
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To: Sonic Zhang <sonic.adi@gmail.com>
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Le vendredi 04 juin 2010 =C3=A0 12:44 +0800, Sonic Zhang a =C3=A9crit :

>=20
> Yes, you are right. dev_kfree_skb_irq() queues used skb to the
> complete queue. But, it is actually freed in the other soft irq
> NET_TX_SOFTIRQ.

I guess you didnt understood my mail, so I'll re-explain :

dev_kfree_skb_irq() queues skb only if packet is not already orphaned.

As most packets are now orphaned (in recent kernels where your patch
applies), dev_kfree_skb_irq() can free packet immediately, with no
NET_TX_SOFTIRQ overhead.