From 0dad4087a86a2cbe177404dc73f18ada26a2c390 Mon Sep 17 00:00:00 2001
From: Eric Dumazet <edumazet@google.com>
Date: Mon, 24 Jan 2022 12:24:54 -0800
Subject: [PATCH] tcp/dccp: get rid of inet_twsk_purge()
Prior patches in the series made sure tw_timer_handler()
can be fired after netns has been dismantled/freed.
We no longer have to scan a potentially big TCP ehash
table at netns dismantle.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
include/net/inet_timewait_sock.h | 2 --
net/dccp/ipv4.c | 6 ----
net/dccp/ipv6.c | 6 ----
net/ipv4/inet_timewait_sock.c | 47 --------------------------------
net/ipv4/tcp_ipv4.c | 2 --
net/ipv6/tcp_ipv6.c | 6 ----
6 files changed, 69 deletions(-)
diff --git a/include/net/inet_timewait_sock.h b/include/net/inet_timewait_sock.h
index b323db969b8b6..463ae5d33eb09 100644
--- a/include/net/inet_timewait_sock.h
+++ b/include/net/inet_timewait_sock.h
@@ -110,8 +110,6 @@ static inline void inet_twsk_reschedule(struct inet_timewait_sock *tw, int timeo
void inet_twsk_deschedule_put(struct inet_timewait_sock *tw);
-void inet_twsk_purge(struct inet_hashinfo *hashinfo, int family);
-
static inline
struct net *twsk_net(const struct inet_timewait_sock *twsk)
{
diff --git a/net/dccp/ipv4.c b/net/dccp/ipv4.c
index 0ea29270d7e53..ae662567a6cb6 100644
--- a/net/dccp/ipv4.c
+++ b/net/dccp/ipv4.c
@@ -1030,15 +1030,9 @@ static void __net_exit dccp_v4_exit_net(struct net *net)
inet_ctl_sock_destroy(pn->v4_ctl_sk);
}
-static void __net_exit dccp_v4_exit_batch(struct list_head *net_exit_list)
-{
- inet_twsk_purge(&dccp_hashinfo, AF_INET);
-}
-
static struct pernet_operations dccp_v4_ops = {
.init = dccp_v4_init_net,
.exit = dccp_v4_exit_net,
- .exit_batch = dccp_v4_exit_batch,
.id = &dccp_v4_pernet_id,
.size = sizeof(struct dccp_v4_pernet),
};
diff --git a/net/dccp/ipv6.c b/net/dccp/ipv6.c
index fa663518fa0e4..eab3bd1ee9a0a 100644
--- a/net/dccp/ipv6.c
+++ b/net/dccp/ipv6.c
@@ -1115,15 +1115,9 @@ static void __net_exit dccp_v6_exit_net(struct net *net)
inet_ctl_sock_destroy(pn->v6_ctl_sk);
}
-static void __net_exit dccp_v6_exit_batch(struct list_head *net_exit_list)
-{
- inet_twsk_purge(&dccp_hashinfo, AF_INET6);
-}
-
static struct pernet_operations dccp_v6_ops = {
.init = dccp_v6_init_net,
.exit = dccp_v6_exit_net,
- .exit_batch = dccp_v6_exit_batch,
.id = &dccp_v6_pernet_id,
.size = sizeof(struct dccp_v6_pernet),
};
diff --git a/net/ipv4/inet_timewait_sock.c b/net/ipv4/inet_timewait_sock.c
index e37e4852711c5..71808c7a7025c 100644
--- a/net/ipv4/inet_timewait_sock.c
+++ b/net/ipv4/inet_timewait_sock.c
@@ -255,50 +255,3 @@ void __inet_twsk_schedule(struct inet_timewait_sock *tw, int timeo, bool rearm)
}
}
EXPORT_SYMBOL_GPL(__inet_twsk_schedule);
-
-void inet_twsk_purge(struct inet_hashinfo *hashinfo, int family)
-{
- struct inet_timewait_sock *tw;
- struct sock *sk;
- struct hlist_nulls_node *node;
- unsigned int slot;
-
- for (slot = 0; slot <= hashinfo->ehash_mask; slot++) {
- struct inet_ehash_bucket *head = &hashinfo->ehash[slot];
-restart_rcu:
- cond_resched();
- rcu_read_lock();
-restart:
- sk_nulls_for_each_rcu(sk, node, &head->chain) {
- if (sk->sk_state != TCP_TIME_WAIT)
- continue;
- tw = inet_twsk(sk);
- if ((tw->tw_family != family) ||
- refcount_read(&twsk_net(tw)->ns.count))
- continue;
-
- if (unlikely(!refcount_inc_not_zero(&tw->tw_refcnt)))
- continue;
-
- if (unlikely((tw->tw_family != family) ||
- refcount_read(&twsk_net(tw)->ns.count))) {
- inet_twsk_put(tw);
- goto restart;
- }
-
- rcu_read_unlock();
- local_bh_disable();
- inet_twsk_deschedule_put(tw);
- local_bh_enable();
- goto restart_rcu;
- }
- /* If the nulls value we got at the end of this lookup is
- * not the expected one, we must restart lookup.
- * We probably met an item that was moved to another chain.
- */
- if (get_nulls_value(node) != slot)
- goto restart;
- rcu_read_unlock();
- }
-}
-EXPORT_SYMBOL_GPL(inet_twsk_purge);
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index b3f34e366b27f..8e94b99882044 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -3239,8 +3239,6 @@ static void __net_exit tcp_sk_exit_batch(struct list_head *net_exit_list)
{
struct net *net;
- inet_twsk_purge(&tcp_hashinfo, AF_INET);
-
list_for_each_entry(net, net_exit_list, exit_list)
tcp_fastopen_ctx_destroy(net);
}
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 075ee8a2df3b7..1e55ee98dfeda 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -2237,15 +2237,9 @@ static void __net_exit tcpv6_net_exit(struct net *net)
inet_ctl_sock_destroy(net->ipv6.tcp_sk);
}
-static void __net_exit tcpv6_net_exit_batch(struct list_head *net_exit_list)
-{
- inet_twsk_purge(&tcp_hashinfo, AF_INET6);
-}
-
static struct pernet_operations tcpv6_net_ops = {
.init = tcpv6_net_init,
.exit = tcpv6_net_exit,
- .exit_batch = tcpv6_net_exit_batch,
};
int __init tcpv6_init(void)