On Sat, 2014-09-27 at 16:25 -0700, Eric Dumazet wrote:

From: Eric Dumazet <edumazet@google.com>

Lets use a proper structure to clearly document and implement
skb fast clones.

Then, we might experiment more easily alternative layouts.

This patch adds a new skb_fclone_busy() helper, used by tcp and xfrm.

Signed-off-by: Eric Dumazet <edumazet@google.com>
---
 include/linux/skbuff.h |   25 ++++++++++++++++++++++
 net/core/skbuff.c      |   44 +++++++++++++++++++--------------------
 net/ipv4/tcp_output.c  |    5 ----
 net/xfrm/xfrm_policy.c |    4 ---
 4 files changed, 49 insertions(+), 29 deletions(-)

I'll rebase this patch and send a v2.