From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [RFC] skb: avoid unnecessary reallocations in __skb_cow
Date: Tue, 29 May 2012 15:26:07 +0200
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To: Felix Fietkau <nbd@openwrt.org>
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On Tue, 2012-05-29 at 15:10 +0200, Felix Fietkau wrote:

> I don't have any real use case in mind, but it's not really adding an
> extra NET_SKB_PAD, it simply fills up the headroom to NET_SKB_PAD,

This is not what is doing your patch.

If cloned is true, and current skb headroom less than 64, you add an
extra 64 bytes of headroom.

Just keep it simple, this is inline code and should be kept as small as
possible.