From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH 3/4 v2 net-next] net: make GRO aware of skb->head_frag
Date: Wed, 02 May 2012 18:27:51 +0200
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Cc: Alexander Duyck <alexander.duyck@gmail.com>,
	David Miller <davem@davemloft.net>,
	netdev <netdev@vger.kernel.org>,
	Neal Cardwell <ncardwell@google.com>,
	Tom Herbert <therbert@google.com>,
	Jeff Kirsher <jeffrey.t.kirsher@intel.com>,
	Michael Chan <mchan@broadcom.com>,
	Matt Carlson <mcarlson@broadcom.com>,
	Herbert Xu <herbert@gondor.apana.org.au>,
	Ben Hutchings <bhutchings@solarflare.com>,
	Ilpo =?ISO-8859-1?Q?J=E4rvinen?= <ilpo.jarvinen@helsinki.fi>,
	Maciej =?UTF-8?Q?=C5=BBenczykowski?= <maze@google.com>
To: Alexander Duyck <alexander.h.duyck@intel.com>
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On Wed, 2012-05-02 at 18:19 +0200, Eric Dumazet wrote:
> On Wed, 2012-05-02 at 09:16 -0700, Alexander Duyck wrote:
> 
> > I was working with the out-of-tree ixgbe because I have the option there
> > of stripping out FCoE and RSC via a couple of build flags.  The problem
> > is I don't know if the head frag stuff will work out very well with
> > ixgbe because RSC and FCoE require that we have to use 1K aligned
> > receive buffers.  It would require us to make us have to bump up our
> > allocation size by NET_SKB_PAD plus skb_shared_info which would likely
> > force us up to order 1 pages on most platforms.
> 
> What is RSC exactly, and why RSC is used in the build_skb() context ?
> 
> 

It looks like e1000e would be a good candidate for build_skb()
(without packet split)