From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eyal Birger Subject: [PATCH net-next 2/3] net: use skb->priority for overloading skb->dropcount and skb->reserved_tailroom instead of skb->mark Date: Mon, 9 Feb 2015 20:15:22 +0200 Message-ID: <1423505723-2281-3-git-send-email-eyal.birger@gmail.com> References: <1423505723-2281-1-git-send-email-eyal.birger@gmail.com> Cc: edumazet@google.com, netdev@vger.kernel.org, Eyal Birger To: davem@davemloft.net Return-path: Received: from mail-wi0-f176.google.com ([209.85.212.176]:41935 "EHLO mail-wi0-f176.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933674AbbBISPo (ORCPT ); Mon, 9 Feb 2015 13:15:44 -0500 Received: by mail-wi0-f176.google.com with SMTP id hm9so8455663wib.3 for ; Mon, 09 Feb 2015 10:15:43 -0800 (PST) In-Reply-To: <1423505723-2281-1-git-send-email-eyal.birger@gmail.com> Sender: netdev-owner@vger.kernel.org List-ID: Commit 977750076d98 ("af_packet: add interframe drop cmsg (v6)") unionized skb->mark and skb->dropcount in order to allow recording of the socket drop count while maintaining struct sk_buff size. In order to allow for the skb->mark to be fetched by user-space code it needs to be detached from this union; skb->priority is used instead. Signed-off-by: Eyal Birger ---- The purpose of overloading skb->priority is solely for retaining struct sk_buff size; skb->priority is not used after the skb queued to the socket and has the same guarentee of not being shared as skb->mark. --- include/linux/skbuff.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 1bb36ed..23f1a94 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -621,7 +621,7 @@ struct sk_buff { __u16 csum_offset; }; }; - __u32 priority; + __u32 mark; int skb_iif; __u32 hash; __be16 vlan_proto; @@ -636,7 +636,7 @@ struct sk_buff { __u32 secmark; #endif union { - __u32 mark; + __u32 priority; __u32 dropcount; __u32 reserved_tailroom; }; -- 2.1.4