From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jarek Poplawski <jarkao2@gmail.com>
Subject: Re: [PATCH net-next-2.6] net: pskb_expand_head() optimization
Date: Sun, 12 Sep 2010 22:57:22 +0200
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On Sun, Sep 12, 2010 at 09:13:53AM -0700, David Miller wrote:
> 
> BTW, Jarek, as to your idea to store a tail pointer in the shinfo, how
> will you sync that tail pointer in all of the shinfo instances
> referencing the frag list?
> 
> It simply can't work, we have to copy.

The question is if we need to sync at all? This is shared data at the
moment, so I can't imagine how the list (especialy doubly linked)
could be changed without locking? And even if it's possible, I doubt
copying e.g. like in your current patch can help when an skb is added
at the tail later.

Jarek P.