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Date: Thu, 3 Dec 2009 04:29:09 -0800
From: "Eric W. Biederman" <ebiederm@...ssion.com>
To: David Miller <davem@...emloft.net>
Cc: <netdev@...r.kernel.org>, jamal <hadi@...erus.ca>,
Daniel Lezcano <dlezcano@...ibm.com>,
"Eric W. Biederman" <ebiederm@...ssion.com>
Subject: [PATCH 7/7] net: Batch inet_twsk_purge
From: Eric W. Biederman <ebiederm@...ssion.com>
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 <ebiederm@...ssion.com>
---
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 773b10f..4fd007f 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 683ecec..a3699ac 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 df18ce0..e30f026 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -2468,12 +2468,17 @@ 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 de70909..5f46d36 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -2126,12 +2126,17 @@ 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)
--
1.6.5.2.143.g8cc62
--
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