From 8073e960a03bf7b5d5ebfc5ff18ac475e1688f46 Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Wed, 6 Sep 2017 14:39:52 +0200 Subject: [PATCH] netfilter: nat: use keyed locks no need to serialize on a single lock, we can partition the table and add/delete in parallel to different slots. This restores one of the advantages that got lost with the rhlist revert. Cc: Ivan Babrou Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_nat_core.c | 36 ++++++++++++++++++++++++------------ 1 file changed, 24 insertions(+), 12 deletions(-) diff --git a/net/netfilter/nf_nat_core.c b/net/netfilter/nf_nat_core.c index f090419f5f97..f393a7086025 100644 --- a/net/netfilter/nf_nat_core.c +++ b/net/netfilter/nf_nat_core.c @@ -30,7 +30,7 @@ #include #include -static DEFINE_SPINLOCK(nf_nat_lock); +static spinlock_t nf_nat_locks[CONNTRACK_LOCKS]; static DEFINE_MUTEX(nf_nat_proto_mutex); static const struct nf_nat_l3proto __rcu *nf_nat_l3protos[NFPROTO_NUMPROTO] @@ -425,13 +425,15 @@ nf_nat_setup_info(struct nf_conn *ct, if (maniptype == NF_NAT_MANIP_SRC) { unsigned int srchash; + spinlock_t *lock; srchash = hash_by_src(net, &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple); - spin_lock_bh(&nf_nat_lock); + lock = &nf_nat_locks[srchash % ARRAY_SIZE(nf_nat_locks)]; + spin_lock_bh(lock); hlist_add_head_rcu(&ct->nat_bysource, &nf_nat_bysource[srchash]); - spin_unlock_bh(&nf_nat_lock); + spin_unlock_bh(lock); } /* It's done. */ @@ -525,6 +527,16 @@ static int nf_nat_proto_remove(struct nf_conn *i, void *data) return i->status & IPS_NAT_MASK ? 1 : 0; } +static void __nf_nat_cleanup_conntrack(struct nf_conn *ct) +{ + unsigned int h; + + h = hash_by_src(nf_ct_net(ct), &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple); + spin_lock_bh(&nf_nat_locks[h % ARRAY_SIZE(nf_nat_locks)]); + hlist_del_rcu(&ct->nat_bysource); + spin_unlock_bh(&nf_nat_locks[h % ARRAY_SIZE(nf_nat_locks)]); +} + static int nf_nat_proto_clean(struct nf_conn *ct, void *data) { if (nf_nat_proto_remove(ct, data)) @@ -540,9 +552,7 @@ static int nf_nat_proto_clean(struct nf_conn *ct, void *data) * will delete entry from already-freed table. */ clear_bit(IPS_SRC_NAT_DONE_BIT, &ct->status); - spin_lock_bh(&nf_nat_lock); - hlist_del_rcu(&ct->nat_bysource); - spin_unlock_bh(&nf_nat_lock); + __nf_nat_cleanup_conntrack(ct); /* don't delete conntrack. Although that would make things a lot * simpler, we'd end up flushing all conntracks on nat rmmod. @@ -670,11 +680,8 @@ EXPORT_SYMBOL_GPL(nf_nat_l3proto_unregister); /* No one using conntrack by the time this called. */ static void nf_nat_cleanup_conntrack(struct nf_conn *ct) { - if (ct->status & IPS_SRC_NAT_DONE) { - spin_lock_bh(&nf_nat_lock); - hlist_del_rcu(&ct->nat_bysource); - spin_unlock_bh(&nf_nat_lock); - } + if (ct->status & IPS_SRC_NAT_DONE) + __nf_nat_cleanup_conntrack(ct); } static struct nf_ct_ext_type nat_extend __read_mostly = { @@ -796,10 +803,12 @@ static struct nf_ct_helper_expectfn follow_master_nat = { static int __init nf_nat_init(void) { - int ret; + int ret, i; /* Leave them the same for the moment. */ nf_nat_htable_size = nf_conntrack_htable_size; + if (nf_nat_htable_size < ARRAY_SIZE(nf_nat_locks)) + nf_nat_htable_size = ARRAY_SIZE(nf_nat_locks); nf_nat_bysource = nf_ct_alloc_hashtable(&nf_nat_htable_size, 0); if (!nf_nat_bysource) @@ -812,6 +821,9 @@ static int __init nf_nat_init(void) return ret; } + for (i = 0; i < ARRAY_SIZE(nf_nat_locks); i++) + spin_lock_init(&nf_nat_locks[i]); + nf_ct_helper_expectfn_register(&follow_master_nat); BUG_ON(nfnetlink_parse_nat_setup_hook != NULL); -- 2.20.1