From b3c5163fe0193a74016dba1bb22491e0d1e9aaa4 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Wed, 9 Jun 2010 14:43:38 +0200 Subject: [PATCH] netfilter: nf_conntrack: per_cpu untracking NOTRACK makes all cpus share a cache line on nf_conntrack_untracked twice per packet, slowing down performance. This patch converts it to a per_cpu variable. Signed-off-by: Eric Dumazet Signed-off-by: Patrick McHardy --- include/net/netfilter/nf_conntrack.h | 5 ++-- net/netfilter/nf_conntrack_core.c | 36 ++++++++++++++++++++-------- 2 files changed, 28 insertions(+), 13 deletions(-) diff --git a/include/net/netfilter/nf_conntrack.h b/include/net/netfilter/nf_conntrack.h index 3bc38c70bbbe..84a4b6fec99d 100644 --- a/include/net/netfilter/nf_conntrack.h +++ b/include/net/netfilter/nf_conntrack.h @@ -261,11 +261,10 @@ extern s16 (*nf_ct_nat_offset)(const struct nf_conn *ct, u32 seq); /* Fake conntrack entry for untracked connections */ +DECLARE_PER_CPU(struct nf_conn, nf_conntrack_untracked); static inline struct nf_conn *nf_ct_untracked_get(void) { - extern struct nf_conn nf_conntrack_untracked; - - return &nf_conntrack_untracked; + return &__raw_get_cpu_var(nf_conntrack_untracked); } extern void nf_ct_untracked_status_or(unsigned long bits); diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c index 6c1da212380d..9c661413b826 100644 --- a/net/netfilter/nf_conntrack_core.c +++ b/net/netfilter/nf_conntrack_core.c @@ -62,8 +62,8 @@ EXPORT_SYMBOL_GPL(nf_conntrack_htable_size); unsigned int nf_conntrack_max __read_mostly; EXPORT_SYMBOL_GPL(nf_conntrack_max); -struct nf_conn nf_conntrack_untracked; -EXPORT_SYMBOL_GPL(nf_conntrack_untracked); +DEFINE_PER_CPU(struct nf_conn, nf_conntrack_untracked); +EXPORT_PER_CPU_SYMBOL(nf_conntrack_untracked); static int nf_conntrack_hash_rnd_initted; static unsigned int nf_conntrack_hash_rnd; @@ -1183,10 +1183,21 @@ static void nf_ct_release_dying_list(struct net *net) spin_unlock_bh(&nf_conntrack_lock); } +static int untrack_refs(void) +{ + int cnt = 0, cpu; + + for_each_possible_cpu(cpu) { + struct nf_conn *ct = &per_cpu(nf_conntrack_untracked, cpu); + + cnt += atomic_read(&ct->ct_general.use) - 1; + } + return cnt; +} + static void nf_conntrack_cleanup_init_net(void) { - /* wait until all references to nf_conntrack_untracked are dropped */ - while (atomic_read(&nf_conntrack_untracked.ct_general.use) > 1) + while (untrack_refs() > 0) schedule(); nf_conntrack_helper_fini(); @@ -1323,14 +1334,17 @@ module_param_call(hashsize, nf_conntrack_set_hashsize, param_get_uint, void nf_ct_untracked_status_or(unsigned long bits) { - nf_conntrack_untracked.status |= bits; + int cpu; + + for_each_possible_cpu(cpu) + per_cpu(nf_conntrack_untracked, cpu).status |= bits; } EXPORT_SYMBOL_GPL(nf_ct_untracked_status_or); static int nf_conntrack_init_init_net(void) { int max_factor = 8; - int ret; + int ret, cpu; /* Idea from tcp.c: use 1/16384 of memory. On i386: 32MB * machine has 512 buckets. >= 1GB machines have 16384 buckets. */ @@ -1369,10 +1383,12 @@ static int nf_conntrack_init_init_net(void) goto err_extend; #endif /* Set up fake conntrack: to never be deleted, not in any hashes */ -#ifdef CONFIG_NET_NS - nf_conntrack_untracked.ct_net = &init_net; -#endif - atomic_set(&nf_conntrack_untracked.ct_general.use, 1); + for_each_possible_cpu(cpu) { + struct nf_conn *ct = &per_cpu(nf_conntrack_untracked, cpu); + + write_pnet(&ct->ct_net, &init_net); + atomic_set(&ct->ct_general.use, 1); + } /* - and look it like as a confirmed connection */ nf_ct_untracked_status_or(IPS_CONFIRMED | IPS_UNTRACKED); return 0; -- 2.30.2