net: use dst_cache for vxlan device

In case of UDP traffic with datagram length
below MTU this give about 3% performance increase
when tunneling over ipv4 and about 70% 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>

diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index 0a23c64..ad67303 100644 (file)
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -480,6 +480,8 @@ static int vxlan_fdb_replace(struct vxlan_fdb *f,
        rd = list_first_entry_or_null(&f->remotes, struct vxlan_rdst, list);
        if (!rd)
                return 0;
+
+       dst_cache_reset(&rd->dst_cache);
        rd->remote_ip = *ip;
        rd->remote_port = port;
        rd->remote_vni = vni;
@@ -501,6 +503,12 @@ static int vxlan_fdb_append(struct vxlan_fdb *f,
        rd = kmalloc(sizeof(*rd), GFP_ATOMIC);
        if (rd == NULL)
                return -ENOBUFS;
+
+       if (dst_cache_init(&rd->dst_cache, GFP_ATOMIC)) {
+               kfree(rd);
+               return -ENOBUFS;
+       }
+
        rd->remote_ip = *ip;
        rd->remote_port = port;
        rd->remote_vni = vni;
@@ -749,8 +757,10 @@ static void vxlan_fdb_free(struct rcu_head *head)
        struct vxlan_fdb *f = container_of(head, struct vxlan_fdb, rcu);
        struct vxlan_rdst *rd, *nd;
 
-       list_for_each_entry_safe(rd, nd, &f->remotes, list)
+       list_for_each_entry_safe(rd, nd, &f->remotes, list) {
+               dst_cache_destroy(&rd->dst_cache);
                kfree(rd);
+       }
        kfree(f);
 }
 
@@ -1754,11 +1764,24 @@ static int vxlan_build_skb(struct sk_buff *skb, struct dst_entry *dst,
 
 static struct rtable *vxlan_get_route(struct vxlan_dev *vxlan,
                                      struct sk_buff *skb, int oif, u8 tos,
-                                     __be32 daddr, __be32 *saddr)
+                                     __be32 daddr, __be32 *saddr,
+                                     struct dst_cache *dst_cache,
+                                     struct ip_tunnel_info *info)
 {
        struct rtable *rt = NULL;
+       bool use_cache = false;
        struct flowi4 fl4;
 
+       /* when the ip_tunnel_info is availble, the tos used for lookup is
+        * packet independent, so we can use the cache
+        */
+       if (dst_cache && !skb->mark && (!tos || info)) {
+               use_cache = true;
+               rt = dst_cache_get_ip4(dst_cache, saddr);
+               if (rt)
+                       return rt;
+       }
+
        memset(&fl4, 0, sizeof(fl4));
        fl4.flowi4_oif = oif;
        fl4.flowi4_tos = RT_TOS(tos);
@@ -1768,8 +1791,11 @@ static struct rtable *vxlan_get_route(struct vxlan_dev *vxlan,
        fl4.saddr = vxlan->cfg.saddr.sin.sin_addr.s_addr;
 
        rt = ip_route_output_key(vxlan->net, &fl4);
-       if (!IS_ERR(rt))
+       if (!IS_ERR(rt)) {
                *saddr = fl4.saddr;
+               if (use_cache)
+                       dst_cache_set_ip4(dst_cache, &rt->dst, fl4.saddr);
+       }
        return rt;
 }
 
@@ -1777,12 +1803,21 @@ static struct rtable *vxlan_get_route(struct vxlan_dev *vxlan,
 static struct dst_entry *vxlan6_get_route(struct vxlan_dev *vxlan,
                                          struct sk_buff *skb, int oif,
                                          const struct in6_addr *daddr,
-                                         struct in6_addr *saddr)
+                                         struct in6_addr *saddr,
+                                         struct dst_cache *dst_cache)
 {
+       bool use_cache = false;
        struct dst_entry *ndst;
        struct flowi6 fl6;
        int err;
 
+       if (dst_cache && !skb->mark) {
+               use_cache = true;
+               ndst = dst_cache_get_ip6(dst_cache, saddr);
+               if (ndst)
+                       return ndst;
+       }
+
        memset(&fl6, 0, sizeof(fl6));
        fl6.flowi6_oif = oif;
        fl6.daddr = *daddr;
@@ -1797,6 +1832,8 @@ static struct dst_entry *vxlan6_get_route(struct vxlan_dev *vxlan,
                return ERR_PTR(err);
 
        *saddr = fl6.saddr;
+       if (use_cache)
+               dst_cache_set_ip6(dst_cache, ndst, saddr);
        return ndst;
 }
 #endif
@@ -1938,7 +1975,8 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
 
                rt = vxlan_get_route(vxlan, skb,
                                     rdst ? rdst->remote_ifindex : 0, tos,
-                                    dst->sin.sin_addr.s_addr, &saddr);
+                                    dst->sin.sin_addr.s_addr, &saddr,
+                                    rdst ? &rdst->dst_cache : NULL, info);
                if (IS_ERR(rt)) {
                        netdev_dbg(dev, "no route to %pI4\n",
                                   &dst->sin.sin_addr.s_addr);
@@ -1990,7 +2028,8 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
 
                ndst = vxlan6_get_route(vxlan, skb,
                                        rdst ? rdst->remote_ifindex : 0,
-                                       &dst->sin6.sin6_addr, &saddr);
+                                       &dst->sin6.sin6_addr, &saddr,
+                                       rdst ? &rdst->dst_cache : NULL);
                if (IS_ERR(ndst)) {
                        netdev_dbg(dev, "no route to %pI6\n",
                                   &dst->sin6.sin6_addr);
@@ -2331,7 +2370,7 @@ static int vxlan_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb)
                        return -EINVAL;
                rt = vxlan_get_route(vxlan, skb, 0, info->key.tos,
                                     info->key.u.ipv4.dst,
-                                    &info->key.u.ipv4.src);
+                                    &info->key.u.ipv4.src, NULL, info);
                if (IS_ERR(rt))
                        return PTR_ERR(rt);
                ip_rt_put(rt);
@@ -2343,7 +2382,7 @@ static int vxlan_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb)
                        return -EINVAL;
                ndst = vxlan6_get_route(vxlan, skb, 0,
                                        &info->key.u.ipv6.dst,
-                                       &info->key.u.ipv6.src);
+                                       &info->key.u.ipv6.src, NULL);
                if (IS_ERR(ndst))
                        return PTR_ERR(ndst);
                dst_release(ndst);

diff --git a/include/net/vxlan.h b/include/net/vxlan.h
index 25bd919..b314e4a 100644 (file)
--- a/include/net/vxlan.h
+++ b/include/net/vxlan.h
@@ -148,6 +148,7 @@ struct vxlan_rdst {
        u32                      remote_ifindex;
        struct list_head         list;
        struct rcu_head          rcu;
+       struct dst_cache         dst_cache;
 };
 
 struct vxlan_config {