net: add dst_cache to ovs vxlan lwtunnel

In case of UDP traffic with datagram length
below MTU this give about 2% performance increase
when tunneling over ipv4 and about 60% when tunneling
over ipv6

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Suggested-and-acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 7 insertions, 0 deletions

diff --git a/net/openvswitch/Kconfig b/net/openvswitch/Kconfig
index d143aa9f6654..cd5fd9d728a7 100644
--- a/net/openvswitch/Kconfig
+++ b/net/openvswitch/Kconfig
@@ -10,6 +10,7 @@ config OPENVSWITCH
         select LIBCRC32C
         select MPLS
         select NET_MPLS_GSO
+        select DST_CACHE
         ---help---
           Open vSwitch is a multilayer Ethernet switch targeted at virtualized
           environments.  In addition to supporting a variety of features
diff --git a/net/openvswitch/flow_netlink.c b/net/openvswitch/flow_netlink.c
index d1bd4a45ca2d..58b8efc23668 100644
--- a/net/openvswitch/flow_netlink.c
+++ b/net/openvswitch/flow_netlink.c
@@ -1959,6 +1959,12 @@ static int validate_and_copy_set_tun(const struct nlattr *attr,
         if (!tun_dst)
                 return -ENOMEM;
 
+        err = dst_cache_init(&tun_dst->u.tun_info.dst_cache, GFP_KERNEL);
+        if (err) {
+                dst_release((struct dst_entry *)tun_dst);
+                return err;
+        }
+
         a = __add_action(sfa, OVS_KEY_ATTR_TUNNEL_INFO, NULL,
                          sizeof(*ovs_tun), log);
         if (IS_ERR(a)) {