[NET] NETNS: Omit sock->sk_net without CONFIG_NET_NS.

Introduce per-sock inlines: sock_net(), sock_net_set()
and per-inet_timewait_sock inlines: twsk_net(), twsk_net_set().
Without CONFIG_NET_NS, no namespace other than &init_net exists.
Let's explicitly define them to help compiler optimizations.

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

1 files changed, 18 insertions, 0 deletions

diff --git a/include/net/inet_timewait_sock.h b/include/net/inet_timewait_sock.h
index 296547bfb0b7..07fe0d1a4f03 100644
--- a/include/net/inet_timewait_sock.h
+++ b/include/net/inet_timewait_sock.h
@@ -207,4 +207,22 @@ extern void inet_twsk_schedule(struct inet_timewait_sock *tw,
                                const int timeo, const int timewait_len);
 extern void inet_twsk_deschedule(struct inet_timewait_sock *tw,
                                  struct inet_timewait_death_row *twdr);
+
+static inline
+struct net *twsk_net(const struct inet_timewait_sock *twsk)
+{
+#ifdef CONFIG_NET_NS
+        return twsk->tw_net;
+#else
+        return &init_net;
+#endif
+}
+
+static inline
+void twsk_net_set(struct inet_timewait_sock *twsk, const struct net *net)
+{
+#ifdef CONFIG_NET_NS
+        twsk->tw_net = net;
+#endif
+}
 #endif  /* _INET_TIMEWAIT_SOCK_ */