From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH net-next-2.6] net: pskb_expand_head() optimization
Date: Mon, 20 Sep 2010 11:02:00 +0200
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Cc: David Miller <davem@davemloft.net>, netdev@vger.kernel.org
To: Jarek Poplawski <jarkao2@gmail.com>
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Le lundi 20 septembre 2010 =C3=A0 07:21 +0000, Jarek Poplawski a =C3=A9=
crit :

> Probably we could start from enhacing moving drivers to paged skbs
> where possible. And maybe simplifying the skb model by not allowing
> frags and frag lists together?
>=20

Sure. I believe current model, pre-allocating skb in huge tx rings is a
waste of mem bandwidth anyway. (I am refering to the struct sk_buff
itself, not the payload part)

Of course some drivers are doing it right, using netdev_alloc_skb()
right before feeding this skb to network stack, not an old one.

> Btw, I wonder what is the exact reason we can't use only
> NET_SKBUFF_DATA_USES_OFFSET?

I see no real reason.

On 32bit arches, it might be faster to manipulate pointers, and not
'base+offset' values.