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 --- net/ipv4/ipvs/ip_vs_core.c | 9 +++++---- net/ipv4/ipvs/ip_vs_xmit.c | 2 +- 2 files changed, 6 insertions(+), 5 deletions(-) (limited to 'net/ipv4/ipvs') diff --git a/net/ipv4/ipvs/ip_vs_core.c b/net/ipv4/ipvs/ip_vs_core.c index 5fb257d..3ac7eec 100644 --- a/net/ipv4/ipvs/ip_vs_core.c +++ b/net/ipv4/ipvs/ip_vs_core.c @@ -22,6 +22,7 @@ * * Changes: * Paul `Rusty' Russell properly handle non-linear skbs + * Harald Welte don't use nfcache * */ @@ -529,7 +530,7 @@ static unsigned int ip_vs_post_routing(unsigned int hooknum, const struct net_device *out, int (*okfn)(struct sk_buff *)) { - if (!((*pskb)->nfcache & NFC_IPVS_PROPERTY)) + if (!((*pskb)->ipvs_property)) return NF_ACCEPT; /* The packet was sent from IPVS, exit this chain */ @@ -701,7 +702,7 @@ static int ip_vs_out_icmp(struct sk_buff **pskb, int *related) /* do the statistics and put it back */ ip_vs_out_stats(cp, skb); - skb->nfcache |= NFC_IPVS_PROPERTY; + skb->ipvs_property = 1; verdict = NF_ACCEPT; out: @@ -739,7 +740,7 @@ ip_vs_out(unsigned int hooknum, struct sk_buff **pskb, EnterFunction(11); - if (skb->nfcache & NFC_IPVS_PROPERTY) + if (skb->ipvs_property) return NF_ACCEPT; iph = skb->nh.iph; @@ -821,7 +822,7 @@ ip_vs_out(unsigned int hooknum, struct sk_buff **pskb, ip_vs_set_state(cp, IP_VS_DIR_OUTPUT, skb, pp); ip_vs_conn_put(cp); - skb->nfcache |= NFC_IPVS_PROPERTY; + skb->ipvs_property = 1; LeaveFunction(11); return NF_ACCEPT; diff --git a/net/ipv4/ipvs/ip_vs_xmit.c b/net/ipv4/ipvs/ip_vs_xmit.c index a8512a3..3b87482 100644 --- a/net/ipv4/ipvs/ip_vs_xmit.c +++ b/net/ipv4/ipvs/ip_vs_xmit.c @@ -127,7 +127,7 @@ ip_vs_dst_reset(struct ip_vs_dest *dest) #define IP_VS_XMIT(skb, rt) \ do { \ - (skb)->nfcache |= NFC_IPVS_PROPERTY; \ + (skb)->ipvs_property = 1; \ (skb)->ip_summed = CHECKSUM_NONE; \ NF_HOOK(PF_INET, NF_IP_LOCAL_OUT, (skb), NULL, \ (rt)->u.dst.dev, dst_output); \ -- cgit v1.1