openvswitch: Enable memory mapped Netlink i/o

Use memory mapped Netlink i/o for all unicast openvswitch
communication if a ring has been set up.

Benchmark
  * pktgen -> ovs internal port
  * 5M pkts, 5M flows
  * 4 threads, 8 cores

Before:
Result: OK: 67418743(c67108212+d310530) usec, 5000000 (9000byte,0frags)
  74163pps 5339Mb/sec (5339736000bps) errors: 0
	+   2.98%     ovs-vswitchd  [k] copy_user_generic_string
	+   2.49%     ovs-vswitchd  [k] memcpy
	+   1.84%       kpktgend_2  [k] memcpy
	+   1.81%       kpktgend_1  [k] memcpy
	+   1.81%       kpktgend_3  [k] memcpy
	+   1.78%       kpktgend_0  [k] memcpy

After:
Result: OK: 24229690(c24127165+d102524) usec, 5000000 (9000byte,0frags)
  206358pps 14857Mb/sec (14857776000bps) errors: 0
	+   2.80%     ovs-vswitchd  [k] memcpy
	+   1.31%       kpktgend_2  [k] memcpy
	+   1.23%       kpktgend_0  [k] memcpy
	+   1.09%       kpktgend_1  [k] memcpy
	+   1.04%       kpktgend_3  [k] memcpy
	+   0.96%     ovs-vswitchd  [k] copy_user_generic_string

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Reviewed-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Jesse Gross <jesse@nicira.com>

1 files changed, 29 insertions, 27 deletions

diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c
index 0727aaa2c825..5da2534b140a 100644
--- a/net/openvswitch/datapath.c
+++ b/net/openvswitch/datapath.c
@@ -402,6 +402,11 @@ static int queue_userspace_packet(struct net *net, int dp_ifindex,
         struct sk_buff *nskb = NULL;
         struct sk_buff *user_skb; /* to be queued to userspace */
         struct nlattr *nla;
+        struct genl_info info = {
+                .dst_sk = net->genl_sock,
+                .snd_portid = upcall_info->portid,
+        };
+        size_t len;
         int err;
 
         if (vlan_tx_tag_present(skb)) {
@@ -422,7 +427,8 @@ static int queue_userspace_packet(struct net *net, int dp_ifindex,
                 goto out;
         }
 
-        user_skb = genlmsg_new(upcall_msg_size(skb, upcall_info->userdata), GFP_ATOMIC);
+        len = upcall_msg_size(skb, upcall_info->userdata);
+        user_skb = genlmsg_new_unicast(len, &info, GFP_ATOMIC);
         if (!user_skb) {
                 err = -ENOMEM;
                 goto out;
@@ -725,27 +731,30 @@ error:
         return err;
 }
 
-static struct sk_buff *ovs_flow_cmd_alloc_info(struct sw_flow *flow)
+static struct sk_buff *ovs_flow_cmd_alloc_info(struct sw_flow *flow,
+                                               struct genl_info *info)
 {
-        const struct sw_flow_actions *sf_acts;
+        size_t len;
 
-        sf_acts = ovsl_dereference(flow->sf_acts);
+        len = ovs_flow_cmd_msg_size(ovsl_dereference(flow->sf_acts));
 
-        return genlmsg_new(ovs_flow_cmd_msg_size(sf_acts), GFP_KERNEL);
+        return genlmsg_new_unicast(len, info, GFP_KERNEL);
 }
 
 static struct sk_buff *ovs_flow_cmd_build_info(struct sw_flow *flow,
                                                struct datapath *dp,
-                                               u32 portid, u32 seq, u8 cmd)
+                                               struct genl_info *info,
+                                               u8 cmd)
 {
         struct sk_buff *skb;
         int retval;
 
-        skb = ovs_flow_cmd_alloc_info(flow);
+        skb = ovs_flow_cmd_alloc_info(flow, info);
         if (!skb)
                 return ERR_PTR(-ENOMEM);
 
-        retval = ovs_flow_cmd_fill_info(flow, dp, skb, portid, seq, 0, cmd);
+        retval = ovs_flow_cmd_fill_info(flow, dp, skb, info->snd_portid,
+                                        info->snd_seq, 0, cmd);
         BUG_ON(retval < 0);
         return skb;
 }
@@ -826,8 +835,7 @@ static int ovs_flow_cmd_new_or_set(struct sk_buff *skb, struct genl_info *info)
                         goto err_flow_free;
                 }
 
-                reply = ovs_flow_cmd_build_info(flow, dp, info->snd_portid,
-                                                info->snd_seq, OVS_FLOW_CMD_NEW);
+                reply = ovs_flow_cmd_build_info(flow, dp, info, OVS_FLOW_CMD_NEW);
         } else {
                 /* We found a matching flow. */
                 struct sw_flow_actions *old_acts;
@@ -855,8 +863,7 @@ static int ovs_flow_cmd_new_or_set(struct sk_buff *skb, struct genl_info *info)
                 rcu_assign_pointer(flow->sf_acts, acts);
                 ovs_nla_free_flow_actions(old_acts);
 
-                reply = ovs_flow_cmd_build_info(flow, dp, info->snd_portid,
-                                               info->snd_seq, OVS_FLOW_CMD_NEW);
+                reply = ovs_flow_cmd_build_info(flow, dp, info, OVS_FLOW_CMD_NEW);
 
                 /* Clear stats. */
                 if (a[OVS_FLOW_ATTR_CLEAR]) {
@@ -918,8 +925,7 @@ static int ovs_flow_cmd_get(struct sk_buff *skb, struct genl_info *info)
                 goto unlock;
         }
 
-        reply = ovs_flow_cmd_build_info(flow, dp, info->snd_portid,
-                                        info->snd_seq, OVS_FLOW_CMD_NEW);
+        reply = ovs_flow_cmd_build_info(flow, dp, info, OVS_FLOW_CMD_NEW);
         if (IS_ERR(reply)) {
                 err = PTR_ERR(reply);
                 goto unlock;
@@ -966,7 +972,7 @@ static int ovs_flow_cmd_del(struct sk_buff *skb, struct genl_info *info)
                 goto unlock;
         }
 
-        reply = ovs_flow_cmd_alloc_info(flow);
+        reply = ovs_flow_cmd_alloc_info(flow, info);
         if (!reply) {
                 err = -ENOMEM;
                 goto unlock;
@@ -1118,17 +1124,17 @@ error:
         return -EMSGSIZE;
 }
 
-static struct sk_buff *ovs_dp_cmd_build_info(struct datapath *dp, u32 portid,
-                                             u32 seq, u8 cmd)
+static struct sk_buff *ovs_dp_cmd_build_info(struct datapath *dp,
+                                             struct genl_info *info, u8 cmd)
 {
         struct sk_buff *skb;
         int retval;
 
-        skb = genlmsg_new(ovs_dp_cmd_msg_size(), GFP_KERNEL);
+        skb = genlmsg_new_unicast(ovs_dp_cmd_msg_size(), info, GFP_KERNEL);
         if (!skb)
                 return ERR_PTR(-ENOMEM);
 
-        retval = ovs_dp_cmd_fill_info(dp, skb, portid, seq, 0, cmd);
+        retval = ovs_dp_cmd_fill_info(dp, skb, info->snd_portid, info->snd_seq, 0, cmd);
         if (retval < 0) {
                 kfree_skb(skb);
                 return ERR_PTR(retval);
@@ -1223,8 +1229,7 @@ static int ovs_dp_cmd_new(struct sk_buff *skb, struct genl_info *info)
                 goto err_destroy_ports_array;
         }
 
-        reply = ovs_dp_cmd_build_info(dp, info->snd_portid,
-                                      info->snd_seq, OVS_DP_CMD_NEW);
+        reply = ovs_dp_cmd_build_info(dp, info, OVS_DP_CMD_NEW);
         err = PTR_ERR(reply);
         if (IS_ERR(reply))
                 goto err_destroy_local_port;
@@ -1290,8 +1295,7 @@ static int ovs_dp_cmd_del(struct sk_buff *skb, struct genl_info *info)
         if (IS_ERR(dp))
                 goto unlock;
 
-        reply = ovs_dp_cmd_build_info(dp, info->snd_portid,
-                                      info->snd_seq, OVS_DP_CMD_DEL);
+        reply = ovs_dp_cmd_build_info(dp, info, OVS_DP_CMD_DEL);
         err = PTR_ERR(reply);
         if (IS_ERR(reply))
                 goto unlock;
@@ -1319,8 +1323,7 @@ static int ovs_dp_cmd_set(struct sk_buff *skb, struct genl_info *info)
         if (IS_ERR(dp))
                 goto unlock;
 
-        reply = ovs_dp_cmd_build_info(dp, info->snd_portid,
-                                      info->snd_seq, OVS_DP_CMD_NEW);
+        reply = ovs_dp_cmd_build_info(dp, info, OVS_DP_CMD_NEW);
         if (IS_ERR(reply)) {
                 err = PTR_ERR(reply);
                 genl_set_err(&dp_datapath_genl_family, sock_net(skb->sk), 0,
@@ -1351,8 +1354,7 @@ static int ovs_dp_cmd_get(struct sk_buff *skb, struct genl_info *info)
                 goto unlock;
         }
 
-        reply = ovs_dp_cmd_build_info(dp, info->snd_portid,
-                                      info->snd_seq, OVS_DP_CMD_NEW);
+        reply = ovs_dp_cmd_build_info(dp, info, OVS_DP_CMD_NEW);
         if (IS_ERR(reply)) {
                 err = PTR_ERR(reply);
                 goto unlock;