ipv4: Namespaceify tcp_tw_recycle and tcp_max_tw_buckets knob

Different namespace application might require fast recycling
TIME-WAIT sockets independently of the host.
Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/inet_timewait_sock.h

@@ -29,16 +29,6 @@
 
 #include <linux/atomic.h>
 
-struct inet_hashinfo;
-
-struct inet_timewait_death_row {
-	atomic_t		tw_count;
-
-	struct inet_hashinfo 	*hashinfo ____cacheline_aligned_in_smp;
-	int			sysctl_tw_recycle;
-	int			sysctl_max_tw_buckets;
-};
-
 struct inet_bind_bucket;
 
 /*
@@ -125,8 +115,7 @@ 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,
-		     struct inet_timewait_death_row *twdr, int family);
+void inet_twsk_purge(struct inet_hashinfo *hashinfo, int family);
 
 static inline
 struct net *twsk_net(const struct inet_timewait_sock *twsk)

include/net/netns/ipv4.h

@@ -27,6 +27,16 @@ struct ping_group_range {
 	kgid_t		range[2];
 };
 
+struct inet_hashinfo;
+
+struct inet_timewait_death_row {
+	atomic_t		tw_count;
+
+	struct inet_hashinfo 	*hashinfo ____cacheline_aligned_in_smp;
+	int			sysctl_tw_recycle;
+	int			sysctl_max_tw_buckets;
+};
+
 struct netns_ipv4 {
 #ifdef CONFIG_SYSCTL
 	struct ctl_table_header	*forw_hdr;
@@ -111,6 +121,7 @@ struct netns_ipv4 {
 	int sysctl_tcp_fin_timeout;
 	unsigned int sysctl_tcp_notsent_lowat;
 	int sysctl_tcp_tw_reuse;
+	struct inet_timewait_death_row tcp_death_row;
 
 	int sysctl_igmp_max_memberships;
 	int sysctl_igmp_max_msf;

include/net/tcp.h

@@ -231,7 +231,6 @@ void tcp_time_wait(struct sock *sk, int state, int timeo);
  */
 #define	TFO_SERVER_WO_SOCKOPT1	0x400
 
-extern struct inet_timewait_death_row tcp_death_row;
 
 /* sysctl variables for tcp */
 extern int sysctl_tcp_timestamps;

net/ipv4/af_inet.c

@@ -1831,8 +1831,6 @@ static int __init inet_init(void)
 
 	ip_init();
 
-	tcp_v4_init();
-
 	/* Setup TCP slab cache for open requests. */
 	tcp_init();
 

net/ipv4/inet_timewait_sock.c

@@ -257,8 +257,7 @@ 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,
-		     struct inet_timewait_death_row *twdr, int family)
+void inet_twsk_purge(struct inet_hashinfo *hashinfo, int family)
 {
 	struct inet_timewait_sock *tw;
 	struct sock *sk;

net/ipv4/proc.c

@@ -65,7 +65,7 @@ static int sockstat_seq_show(struct seq_file *seq, void *v)
 	socket_seq_show(seq);
 	seq_printf(seq, "TCP: inuse %d orphan %d tw %d alloc %d mem %ld\n",
 		   sock_prot_inuse_get(net, &tcp_prot), orphans,
-		   atomic_read(&tcp_death_row.tw_count), sockets,
+		   atomic_read(&net->ipv4.tcp_death_row.tw_count), sockets,
 		   proto_memory_allocated(&tcp_prot));
 	seq_printf(seq, "UDP: inuse %d mem %ld\n",
 		   sock_prot_inuse_get(net, &udp_prot),

net/ipv4/sysctl_net_ipv4.c

@@ -289,13 +289,6 @@ static struct ctl_table ipv4_table[] = {
 		.mode		= 0644,
 		.proc_handler	= proc_dointvec
 	},
-	{
-		.procname	= "tcp_max_tw_buckets",
-		.data		= &tcp_death_row.sysctl_max_tw_buckets,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec
-	},
 	{
 		.procname	= "tcp_fastopen",
 		.data		= &sysctl_tcp_fastopen,
@@ -309,13 +302,6 @@ static struct ctl_table ipv4_table[] = {
 		.maxlen		= ((TCP_FASTOPEN_KEY_LENGTH * 2) + 10),
 		.proc_handler	= proc_tcp_fastopen_key,
 	},
-	{
-		.procname	= "tcp_tw_recycle",
-		.data		= &tcp_death_row.sysctl_tw_recycle,
-		.maxlen		= sizeof(int),
-		.mode		= 0644,
-		.proc_handler	= proc_dointvec
-	},
 	{
 		.procname	= "tcp_abort_on_overflow",
 		.data		= &sysctl_tcp_abort_on_overflow,
@@ -960,6 +946,20 @@ static struct ctl_table ipv4_net_table[] = {
 		.mode		= 0644,
 		.proc_handler	= proc_dointvec
 	},
+	{
+		.procname	= "tcp_max_tw_buckets",
+		.data		= &init_net.ipv4.tcp_death_row.sysctl_max_tw_buckets,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec
+	},
+	{
+		.procname	= "tcp_tw_recycle",
+		.data		= &init_net.ipv4.tcp_death_row.sysctl_tw_recycle,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec
+	},
 #ifdef CONFIG_IP_ROUTE_MULTIPATH
 	{
 		.procname	= "fib_multipath_use_neigh",

net/ipv4/tcp.c

@@ -3334,6 +3334,7 @@ void __init tcp_init(void)
 
 	percpu_counter_init(&tcp_sockets_allocated, 0, GFP_KERNEL);
 	percpu_counter_init(&tcp_orphan_count, 0, GFP_KERNEL);
+	inet_hashinfo_init(&tcp_hashinfo);
 	tcp_hashinfo.bind_bucket_cachep =
 		kmem_cache_create("tcp_bind_bucket",
 				  sizeof(struct inet_bind_bucket), 0,
@@ -3378,7 +3379,6 @@ void __init tcp_init(void)
 
 	cnt = tcp_hashinfo.ehash_mask + 1;
 
-	tcp_death_row.sysctl_max_tw_buckets = cnt / 2;
 	sysctl_tcp_max_orphans = cnt / 2;
 	sysctl_max_syn_backlog = max(128, cnt / 256);
 
@@ -3399,6 +3399,7 @@ void __init tcp_init(void)
 	pr_info("Hash tables configured (established %u bind %u)\n",
 		tcp_hashinfo.ehash_mask + 1, tcp_hashinfo.bhash_size);
 
+	tcp_v4_init();
 	tcp_metrics_init();
 	BUG_ON(tcp_register_congestion_control(&tcp_reno) != 0);
 	tcp_tasklet_init();

net/ipv4/tcp_input.c

@@ -6363,7 +6363,7 @@ int tcp_conn_request(struct request_sock_ops *rsk_ops,
 		 * timewait bucket, so that all the necessary checks
 		 * are made in the function processing timewait state.
 		 */
-		if (tcp_death_row.sysctl_tw_recycle) {
+		if (net->ipv4.tcp_death_row.sysctl_tw_recycle) {
 			bool strict;
 
 			dst = af_ops->route_req(sk, &fl, req, &strict);

net/ipv4/tcp_ipv4.c

@@ -146,6 +146,7 @@ int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 	struct rtable *rt;
 	int err;
 	struct ip_options_rcu *inet_opt;
+	struct inet_timewait_death_row *tcp_death_row = &sock_net(sk)->ipv4.tcp_death_row;
 
 	if (addr_len < sizeof(struct sockaddr_in))
 		return -EINVAL;
@@ -196,7 +197,7 @@ int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 			tp->write_seq	   = 0;
 	}
 
-	if (tcp_death_row.sysctl_tw_recycle &&
+	if (tcp_death_row->sysctl_tw_recycle &&
 	    !tp->rx_opt.ts_recent_stamp && fl4->daddr == daddr)
 		tcp_fetch_timewait_stamp(sk, &rt->dst);
 
@@ -215,7 +216,7 @@ int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 	 * complete initialization after this.
 	 */
 	tcp_set_state(sk, TCP_SYN_SENT);
-	err = inet_hash_connect(&tcp_death_row, sk);
+	err = inet_hash_connect(tcp_death_row, sk);
 	if (err)
 		goto failure;
 
@@ -2457,6 +2458,10 @@ static int __net_init tcp_sk_init(struct net *net)
 	net->ipv4.sysctl_tcp_notsent_lowat = UINT_MAX;
 	net->ipv4.sysctl_tcp_tw_reuse = 0;
 
+	net->ipv4.tcp_death_row.sysctl_tw_recycle = 0;
+	net->ipv4.tcp_death_row.sysctl_max_tw_buckets = (tcp_hashinfo.ehash_mask + 1) / 2;
+	net->ipv4.tcp_death_row.hashinfo = &tcp_hashinfo;
+
 	return 0;
 fail:
 	tcp_sk_exit(net);
@@ -2466,7 +2471,7 @@ static int __net_init tcp_sk_init(struct net *net)
 
 static void __net_exit tcp_sk_exit_batch(struct list_head *net_exit_list)
 {
-	inet_twsk_purge(&tcp_hashinfo, &tcp_death_row, AF_INET);
+	inet_twsk_purge(&tcp_hashinfo, AF_INET);
 }
 
 static struct pernet_operations __net_initdata tcp_sk_ops = {
@@ -2477,7 +2482,6 @@ static struct pernet_operations __net_initdata tcp_sk_ops = {
 
 void __init tcp_v4_init(void)
 {
-	inet_hashinfo_init(&tcp_hashinfo);
 	if (register_pernet_subsys(&tcp_sk_ops))
 		panic("Failed to create the TCP control socket.\n");
 }

net/ipv4/tcp_minisocks.c

@@ -29,12 +29,6 @@
 
 int sysctl_tcp_abort_on_overflow __read_mostly;
 
-struct inet_timewait_death_row tcp_death_row = {
-	.sysctl_max_tw_buckets = NR_FILE * 2,
-	.hashinfo	= &tcp_hashinfo,
-};
-EXPORT_SYMBOL_GPL(tcp_death_row);
-
 static bool tcp_in_window(u32 seq, u32 end_seq, u32 s_win, u32 e_win)
 {
 	if (seq == s_win)
@@ -100,6 +94,7 @@ tcp_timewait_state_process(struct inet_timewait_sock *tw, struct sk_buff *skb,
 	struct tcp_options_received tmp_opt;
 	struct tcp_timewait_sock *tcptw = tcp_twsk((struct sock *)tw);
 	bool paws_reject = false;
+	struct inet_timewait_death_row *tcp_death_row = &sock_net((struct sock*)tw)->ipv4.tcp_death_row;
 
 	tmp_opt.saw_tstamp = 0;
 	if (th->doff > (sizeof(*th) >> 2) && tcptw->tw_ts_recent_stamp) {
@@ -153,7 +148,7 @@ tcp_timewait_state_process(struct inet_timewait_sock *tw, struct sk_buff *skb,
 			tcptw->tw_ts_recent	  = tmp_opt.rcv_tsval;
 		}
 
-		if (tcp_death_row.sysctl_tw_recycle &&
+		if (tcp_death_row->sysctl_tw_recycle &&
 		    tcptw->tw_ts_recent_stamp &&
 		    tcp_tw_remember_stamp(tw))
 			inet_twsk_reschedule(tw, tw->tw_timeout);
@@ -264,11 +259,12 @@ void tcp_time_wait(struct sock *sk, int state, int timeo)
 	const struct tcp_sock *tp = tcp_sk(sk);
 	struct inet_timewait_sock *tw;
 	bool recycle_ok = false;
+	struct inet_timewait_death_row *tcp_death_row = &sock_net(sk)->ipv4.tcp_death_row;
 
-	if (tcp_death_row.sysctl_tw_recycle && tp->rx_opt.ts_recent_stamp)
+	if (tcp_death_row->sysctl_tw_recycle && tp->rx_opt.ts_recent_stamp)
 		recycle_ok = tcp_remember_stamp(sk);
 
-	tw = inet_twsk_alloc(sk, &tcp_death_row, state);
+	tw = inet_twsk_alloc(sk, tcp_death_row, state);
 
 	if (tw) {
 		struct tcp_timewait_sock *tcptw = tcp_twsk((struct sock *)tw);

net/ipv6/tcp_ipv6.c

@@ -123,6 +123,7 @@ static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
 	struct dst_entry *dst;
 	int addr_type;
 	int err;
+	struct inet_timewait_death_row *tcp_death_row = &sock_net(sk)->ipv4.tcp_death_row;
 
 	if (addr_len < SIN6_LEN_RFC2133)
 		return -EINVAL;
@@ -258,7 +259,7 @@ static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
 	sk->sk_gso_type = SKB_GSO_TCPV6;
 	ip6_dst_store(sk, dst, NULL, NULL);
 
-	if (tcp_death_row.sysctl_tw_recycle &&
+	if (tcp_death_row->sysctl_tw_recycle &&
 	    !tp->rx_opt.ts_recent_stamp &&
 	    ipv6_addr_equal(&fl6.daddr, &sk->sk_v6_daddr))
 		tcp_fetch_timewait_stamp(sk, dst);
@@ -273,7 +274,7 @@ static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
 	inet->inet_dport = usin->sin6_port;
 
 	tcp_set_state(sk, TCP_SYN_SENT);
-	err = inet6_hash_connect(&tcp_death_row, sk);
+	err = inet6_hash_connect(tcp_death_row, sk);
 	if (err)
 		goto late_failure;
 
@@ -1948,7 +1949,7 @@ static void __net_exit tcpv6_net_exit(struct net *net)
 
 static void __net_exit tcpv6_net_exit_batch(struct list_head *net_exit_list)
 {
-	inet_twsk_purge(&tcp_hashinfo, &tcp_death_row, AF_INET6);
+	inet_twsk_purge(&tcp_hashinfo, AF_INET6);
 }
 
 static struct pernet_operations tcpv6_net_ops = {