From b099ce2602d806deb41caaa578731848995cdb2a Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Thu, 3 Dec 2009 02:29:09 +0000 Subject: [PATCH] net: Batch inet_twsk_purge This function walks the whole hashtable so there is no point in passing it a network namespace. Instead I purge all timewait sockets from dead network namespaces that I find. If the namespace is one of the once I am trying to purge I am guaranteed no new timewait sockets can be formed so this will get them all. If the namespace is one I am not acting for it might form a few more but I will call inet_twsk_purge again and shortly to get rid of them. In any even if the network namespace is dead timewait sockets are useless. Move the calls of inet_twsk_purge into batch_exit routines so that if I am killing a bunch of namespaces at once I will just call inet_twsk_purge once and save a lot of redundant unnecessary work. My simple 4k network namespace exit test the cleanup time dropped from roughly 8.2s to 1.6s. While the time spent running inet_twsk_purge fell to about 2ms. 1ms for ipv4 and 1ms for ipv6. Signed-off-by: Eric W. Biederman Signed-off-by: David S. Miller --- include/net/inet_timewait_sock.h | 6 +++--- net/ipv4/inet_timewait_sock.c | 10 +++++----- net/ipv4/tcp_ipv4.c | 11 ++++++++--- net/ipv6/tcp_ipv6.c | 11 ++++++++--- 4 files changed, 24 insertions(+), 14 deletions(-) diff --git a/include/net/inet_timewait_sock.h b/include/net/inet_timewait_sock.h index 773b10fa38e4..4fd007f34dd5 100644 --- a/include/net/inet_timewait_sock.h +++ b/include/net/inet_timewait_sock.h @@ -212,14 +212,14 @@ extern void inet_twsk_schedule(struct inet_timewait_sock *tw, extern void inet_twsk_deschedule(struct inet_timewait_sock *tw, struct inet_timewait_death_row *twdr); -extern void inet_twsk_purge(struct net *net, struct inet_hashinfo *hashinfo, +extern void inet_twsk_purge(struct inet_hashinfo *hashinfo, struct inet_timewait_death_row *twdr, int family); static inline struct net *twsk_net(const struct inet_timewait_sock *twsk) { #ifdef CONFIG_NET_NS - return twsk->tw_net; + return rcu_dereference(twsk->tw_net); #else return &init_net; #endif @@ -229,7 +229,7 @@ static inline void twsk_net_set(struct inet_timewait_sock *twsk, struct net *net) { #ifdef CONFIG_NET_NS - twsk->tw_net = net; + rcu_assign_pointer(twsk->tw_net, net); #endif } #endif /* _INET_TIMEWAIT_SOCK_ */ diff --git a/net/ipv4/inet_timewait_sock.c b/net/ipv4/inet_timewait_sock.c index d38ca7c77b93..31f931ef3daf 100644 --- a/net/ipv4/inet_timewait_sock.c +++ b/net/ipv4/inet_timewait_sock.c @@ -421,7 +421,7 @@ out: EXPORT_SYMBOL_GPL(inet_twdr_twcal_tick); -void inet_twsk_purge(struct net *net, struct inet_hashinfo *hashinfo, +void inet_twsk_purge(struct inet_hashinfo *hashinfo, struct inet_timewait_death_row *twdr, int family) { struct inet_timewait_sock *tw; @@ -436,15 +436,15 @@ restart_rcu: restart: sk_nulls_for_each_rcu(sk, node, &head->twchain) { tw = inet_twsk(sk); - if (!net_eq(twsk_net(tw), net) || - tw->tw_family != family) + if ((tw->tw_family != family) || + atomic_read(&twsk_net(tw)->count)) continue; if (unlikely(!atomic_inc_not_zero(&tw->tw_refcnt))) continue; - if (unlikely(!net_eq(twsk_net(tw), net) || - tw->tw_family != family)) { + if (unlikely((tw->tw_family != family) || + atomic_read(&twsk_net(tw)->count))) { inet_twsk_put(tw); goto restart; } diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 59c911f3889d..fee9aabd5aa1 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -2529,12 +2529,17 @@ static int __net_init tcp_sk_init(struct net *net) static void __net_exit tcp_sk_exit(struct net *net) { inet_ctl_sock_destroy(net->ipv4.tcp_sock); - inet_twsk_purge(net, &tcp_hashinfo, &tcp_death_row, AF_INET); +} + +static void __net_exit tcp_sk_exit_batch(struct list_head *net_exit_list) +{ + inet_twsk_purge(&tcp_hashinfo, &tcp_death_row, AF_INET); } static struct pernet_operations __net_initdata tcp_sk_ops = { - .init = tcp_sk_init, - .exit = tcp_sk_exit, + .init = tcp_sk_init, + .exit = tcp_sk_exit, + .exit_batch = tcp_sk_exit_batch, }; void __init tcp_v4_init(void) diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index fc0a4e5895ee..aadd7cef73b3 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -2184,12 +2184,17 @@ static int tcpv6_net_init(struct net *net) static void tcpv6_net_exit(struct net *net) { inet_ctl_sock_destroy(net->ipv6.tcp_sk); - inet_twsk_purge(net, &tcp_hashinfo, &tcp_death_row, AF_INET6); +} + +static void tcpv6_net_exit_batch(struct list_head *net_exit_list) +{ + inet_twsk_purge(&tcp_hashinfo, &tcp_death_row, AF_INET6); } static struct pernet_operations tcpv6_net_ops = { - .init = tcpv6_net_init, - .exit = tcpv6_net_exit, + .init = tcpv6_net_init, + .exit = tcpv6_net_exit, + .exit_batch = tcpv6_net_exit_batch, }; int __init tcpv6_init(void)