From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Michael S. Tsirkin" <mst@redhat.com>
Subject: Re: [PATCH net-next] net: netdev_alloc_skb() use build_skb()
Date: Mon, 4 Jun 2012 15:37:39 +0300
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Cc: Willy Tarreau <w@1wt.eu>, David Miller <davem@davemloft.net>,
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To: Eric Dumazet <eric.dumazet@gmail.com>
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On Thu, May 17, 2012 at 07:34:16PM +0200, Eric Dumazet wrote:
> From: Eric Dumazet <edumazet@google.com>
> 
> Please note I havent tested yet this patch, lacking hardware for this.
> 
> (tg3/bnx2/bnx2x use build_skb, r8169 does a copy of incoming frames,
> ixgbe uses fragments...)

virtio-net uses netdev_alloc_skb but maybe it should call
build_skb instead?

Also, it's not uncommon for drivers to copy short packets out to be able
to reuse pages.  virtio does this but I am guessing the logic is not
really virtio specific.

We could do
	if (len < GOOD_COPY_LEN)
		netdev_alloc_skb
		memmov
	else
		build_skb

but maybe it makes sense to put this logic in build_skb?


-- 
MST