From 6869c4d8e066e21623c812c448a05f1ed931c9c6 Mon Sep 17 00:00:00 2001 From: Harald Welte Date: Tue, 9 Aug 2005 19:24:19 -0700 Subject: [NETFILTER]: reduce netfilter sk_buff enlargement As discussed at netconf'05, we're trying to save every bit in sk_buff. The patch below makes sk_buff 8 bytes smaller. I did some basic testing on my notebook and it seems to work. The only real in-tree user of nfcache was IPVS, who only needs a single bit. Unfortunately I couldn't find some other free bit in sk_buff to stuff that bit into, so I introduced a separate field for them. Maybe the IPVS guys can resolve that to further save space. Initially I wanted to shrink pkt_type to three bits (PACKET_HOST and alike are only 6 values defined), but unfortunately the bluetooth code overloads pkt_type :( The conntrack-event-api (out-of-tree) uses nfcache, but Rusty just came up with a way how to do it without any skb fields, so it's safe to remove it. - remove all never-implemented 'nfcache' code - don't have ipvs code abuse 'nfcache' field. currently get's their own compile-conditional skb->ipvs_property field. IPVS maintainers can decide to move this bit elswhere, but nfcache needs to die. - remove skb->nfcache field to save 4 bytes - move skb->nfctinfo into three unused bits to save further 4 bytes Signed-off-by: Harald Welte Signed-off-by: David S. Miller --- include/linux/netfilter_ipv6.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include/linux/netfilter_ipv6.h') diff --git a/include/linux/netfilter_ipv6.h b/include/linux/netfilter_ipv6.h index bee7a5ec7c66..20c069a5e4ac 100644 --- a/include/linux/netfilter_ipv6.h +++ b/include/linux/netfilter_ipv6.h @@ -10,6 +10,8 @@ #include +/* only for userspace compatibility */ +#ifndef __KERNEL__ /* IP Cache bits. */ /* Src IP address. */ #define NFC_IP6_SRC 0x0001 @@ -38,6 +40,7 @@ #define NFC_IP6_DST_PT 0x0400 /* Something else about the proto */ #define NFC_IP6_PROTO_UNKNOWN 0x2000 +#endif /* ! __KERNEL__ */ /* IP6 Hooks */ -- cgit v1.2.3-59-g8ed1b