ipv6: struct xfrm6_tunnel in read_mostly section

tunnel6_handlers chain being scanned for each incoming packet,
make sure it doesnt share an often dirtied cache line.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv6/ip6_tunnel.c

@@ -1372,13 +1372,13 @@ static void __net_init ip6_fb_tnl_dev_init(struct net_device *dev)
 	ip6n->tnls_wc[0] = t;
 }
 
-static struct xfrm6_tunnel ip4ip6_handler = {
+static struct xfrm6_tunnel ip4ip6_handler __read_mostly = {
 	.handler	= ip4ip6_rcv,
 	.err_handler	= ip4ip6_err,
 	.priority	=	1,
 };
 
-static struct xfrm6_tunnel ip6ip6_handler = {
+static struct xfrm6_tunnel ip6ip6_handler __read_mostly = {
 	.handler	= ip6ip6_rcv,
 	.err_handler	= ip6ip6_err,
 	.priority	=	1,

net/ipv6/tunnel6.c

@@ -30,8 +30,8 @@
 #include <net/protocol.h>
 #include <net/xfrm.h>
 
-static struct xfrm6_tunnel *tunnel6_handlers;
-static struct xfrm6_tunnel *tunnel46_handlers;
+static struct xfrm6_tunnel *tunnel6_handlers __read_mostly;
+static struct xfrm6_tunnel *tunnel46_handlers __read_mostly;
 static DEFINE_MUTEX(tunnel6_mutex);
 
 int xfrm6_tunnel_register(struct xfrm6_tunnel *handler, unsigned short family)

net/ipv6/xfrm6_tunnel.c

@@ -317,13 +317,13 @@ static const struct xfrm_type xfrm6_tunnel_type = {
 	.output		= xfrm6_tunnel_output,
 };
 
-static struct xfrm6_tunnel xfrm6_tunnel_handler = {
+static struct xfrm6_tunnel xfrm6_tunnel_handler __read_mostly = {
 	.handler	= xfrm6_tunnel_rcv,
 	.err_handler	= xfrm6_tunnel_err,
 	.priority	= 2,
 };
 
-static struct xfrm6_tunnel xfrm46_tunnel_handler = {
+static struct xfrm6_tunnel xfrm46_tunnel_handler __read_mostly = {
 	.handler	= xfrm6_tunnel_rcv,
 	.err_handler	= xfrm6_tunnel_err,
 	.priority	= 2,