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>
diff --git a/include/net/netns/ipv4.h b/include/net/netns/ipv4.h
index 0378e88..fffd384 100644
--- a/include/net/netns/ipv4.h
+++ b/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;