static int geneve_tnl_send(struct vport *vport, struct sk_buff *skb)
 {
-       struct ovs_key_ipv4_tunnel *tun_key;
+       const struct ovs_key_ipv4_tunnel *tun_key;
        struct ovs_tunnel_info *tun_info;
        struct net *net = ovs_dp_get_net(vport->dp);
        struct geneve_port *geneve_port = geneve_vport(vport);
        }
 
        tun_key = &tun_info->tunnel;
-
-       /* Route lookup */
-       memset(&fl, 0, sizeof(fl));
-       fl.daddr = tun_key->ipv4_dst;
-       fl.saddr = tun_key->ipv4_src;
-       fl.flowi4_tos = RT_TOS(tun_key->ipv4_tos);
-       fl.flowi4_mark = skb->mark;
-       fl.flowi4_proto = IPPROTO_UDP;
-
-       rt = ip_route_output_key(net, &fl);
+       rt = ovs_tunnel_route_lookup(net, tun_key, skb->mark, &fl, IPPROTO_UDP);
        if (IS_ERR(rt)) {
                err = PTR_ERR(rt);
                goto error;
 
 static int gre_tnl_send(struct vport *vport, struct sk_buff *skb)
 {
        struct net *net = ovs_dp_get_net(vport->dp);
-       struct ovs_key_ipv4_tunnel *tun_key;
+       const struct ovs_key_ipv4_tunnel *tun_key;
        struct flowi4 fl;
        struct rtable *rt;
        int min_headroom;
        }
 
        tun_key = &OVS_CB(skb)->egress_tun_info->tunnel;
-       /* Route lookup */
-       memset(&fl, 0, sizeof(fl));
-       fl.daddr = tun_key->ipv4_dst;
-       fl.saddr = tun_key->ipv4_src;
-       fl.flowi4_tos = RT_TOS(tun_key->ipv4_tos);
-       fl.flowi4_mark = skb->mark;
-       fl.flowi4_proto = IPPROTO_GRE;
-
-       rt = ip_route_output_key(net, &fl);
+       rt = ovs_tunnel_route_lookup(net, tun_key, skb->mark, &fl, IPPROTO_GRE);
        if (IS_ERR(rt)) {
                err = PTR_ERR(rt);
                goto err_free_skb;
 
        struct net *net = ovs_dp_get_net(vport->dp);
        struct vxlan_port *vxlan_port = vxlan_vport(vport);
        __be16 dst_port = inet_sk(vxlan_port->vs->sock->sk)->inet_sport;
-       struct ovs_key_ipv4_tunnel *tun_key;
+       const struct ovs_key_ipv4_tunnel *tun_key;
        struct rtable *rt;
        struct flowi4 fl;
        __be16 src_port;
        }
 
        tun_key = &OVS_CB(skb)->egress_tun_info->tunnel;
-       /* Route lookup */
-       memset(&fl, 0, sizeof(fl));
-       fl.daddr = tun_key->ipv4_dst;
-       fl.saddr = tun_key->ipv4_src;
-       fl.flowi4_tos = RT_TOS(tun_key->ipv4_tos);
-       fl.flowi4_mark = skb->mark;
-       fl.flowi4_proto = IPPROTO_UDP;
-
-       rt = ip_route_output_key(net, &fl);
+       rt = ovs_tunnel_route_lookup(net, tun_key, skb->mark, &fl, IPPROTO_UDP);
        if (IS_ERR(rt)) {
                err = PTR_ERR(rt);
                goto error;
 
         * The process may need to be changed if the corresponding process
         * in vports ops changed.
         */
-       memset(&fl, 0, sizeof(fl));
-       fl.daddr = tun_key->ipv4_dst;
-       fl.saddr = tun_key->ipv4_src;
-       fl.flowi4_tos = RT_TOS(tun_key->ipv4_tos);
-       fl.flowi4_mark = skb_mark;
-       fl.flowi4_proto = ipproto;
-
-       rt = ip_route_output_key(net, &fl);
+       rt = ovs_tunnel_route_lookup(net, tun_key, skb_mark, &fl, ipproto);
        if (IS_ERR(rt))
                return PTR_ERR(rt);
 
 
 int ovs_vport_ops_register(struct vport_ops *ops);
 void ovs_vport_ops_unregister(struct vport_ops *ops);
 
+static inline struct rtable *ovs_tunnel_route_lookup(struct net *net,
+                                                    const struct ovs_key_ipv4_tunnel *key,
+                                                    u32 mark,
+                                                    struct flowi4 *fl,
+                                                    u8 protocol)
+{
+       struct rtable *rt;
+
+       memset(fl, 0, sizeof(*fl));
+       fl->daddr = key->ipv4_dst;
+       fl->saddr = key->ipv4_src;
+       fl->flowi4_tos = RT_TOS(key->ipv4_tos);
+       fl->flowi4_mark = mark;
+       fl->flowi4_proto = protocol;
+
+       rt = ip_route_output_key(net, fl);
+       return rt;
+}
 #endif /* vport.h */