From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH] net: fec: remove memory copy for rx path
Date: Fri, 26 Sep 2014 17:07:20 -0400 (EDT)
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From: Fugang Duan <b38611@freescale.com>
Date: Wed, 24 Sep 2014 14:05:30 +0800

> Re-allocate skb instead of memory copy skb data in rx path to improve
> enet rx performance.
> 
> Signed-off-by: Fugang Duan <B38611@freescale.com>
> Signed-off-by: Frank Li <Frank.Li@freescale.com>

For small packet sizes, copying is almost certainly faster and it avoids
mismatched skb->truesize vs. skb->len which hurts TCP performance.

We call this rx_copybreak, and there are many drivers you can look at
to see how this works.

Thanks.