net: struct xfrm_tunnel in read_mostly section

tunnel4_handlers chain being scanned for each incoming packet,
make sure it doesnt share an often dirtied cache line.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv4/ipip.c

@@ -744,7 +744,7 @@ static void __net_init ipip_fb_tunnel_init(struct net_device *dev)
 	ipn->tunnels_wc[0]	= tunnel;
 }
 
-static struct xfrm_tunnel ipip_handler = {
+static struct xfrm_tunnel ipip_handler __read_mostly = {
 	.handler	=	ipip_rcv,
 	.err_handler	=	ipip_err,
 	.priority	=	1,

net/ipv4/tunnel4.c

@@ -14,8 +14,8 @@
 #include <net/protocol.h>
 #include <net/xfrm.h>
 
-static struct xfrm_tunnel *tunnel4_handlers;
-static struct xfrm_tunnel *tunnel64_handlers;
+static struct xfrm_tunnel *tunnel4_handlers __read_mostly;
+static struct xfrm_tunnel *tunnel64_handlers __read_mostly;
 static DEFINE_MUTEX(tunnel4_mutex);
 
 static inline struct xfrm_tunnel **fam_handlers(unsigned short family)

net/ipv4/xfrm4_tunnel.c

@@ -58,14 +58,14 @@ static int xfrm_tunnel_err(struct sk_buff *skb, u32 info)
 	return -ENOENT;
 }
 
-static struct xfrm_tunnel xfrm_tunnel_handler = {
+static struct xfrm_tunnel xfrm_tunnel_handler __read_mostly = {
 	.handler	=	xfrm_tunnel_rcv,
 	.err_handler	=	xfrm_tunnel_err,
 	.priority	=	2,
 };
 
 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
-static struct xfrm_tunnel xfrm64_tunnel_handler = {
+static struct xfrm_tunnel xfrm64_tunnel_handler __read_mostly = {
 	.handler	=	xfrm_tunnel_rcv,
 	.err_handler	=	xfrm_tunnel_err,
 	.priority	=	2,

net/ipv6/sit.c

@@ -1132,7 +1132,7 @@ static void __net_init ipip6_fb_tunnel_init(struct net_device *dev)
 	sitn->tunnels_wc[0]	= tunnel;
 }
 
-static struct xfrm_tunnel sit_handler = {
+static struct xfrm_tunnel sit_handler __read_mostly = {
 	.handler	=	ipip6_rcv,
 	.err_handler	=	ipip6_err,
 	.priority	=	1,