openvswitch: Per cpu flow stats.

With mega flow implementation ovs flow can be shared between
multiple CPUs which makes stats updates highly contended
operation. This patch uses per-CPU stats in cases where a flow
is likely to be shared (if there is a wildcard in the 5-tuple
and therefore likely to be spread by RSS). In other situations,
it uses the current strategy, saving memory and allocation time.

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: Jesse Gross <jesse@nicira.com>

1 files changed, 16 insertions, 34 deletions

diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c
index 5da2534b140a..50d7782d8d7c 100644
--- a/net/openvswitch/datapath.c
+++ b/net/openvswitch/datapath.c
@@ -251,9 +251,9 @@ void ovs_dp_process_received_packet(struct vport *p, struct sk_buff *skb)
         OVS_CB(skb)->flow = flow;
         OVS_CB(skb)->pkt_key = &key;
 
-        stats_counter = &stats->n_hit;
-        ovs_flow_used(OVS_CB(skb)->flow, skb);
+        ovs_flow_stats_update(OVS_CB(skb)->flow, skb);
         ovs_execute_actions(dp, skb);
+        stats_counter = &stats->n_hit;
 
 out:
         /* Update datapath statistics. */
@@ -459,14 +459,6 @@ out:
         return err;
 }
 
-static void clear_stats(struct sw_flow *flow)
-{
-        flow->used = 0;
-        flow->tcp_flags = 0;
-        flow->packet_count = 0;
-        flow->byte_count = 0;
-}
-
 static int ovs_packet_cmd_execute(struct sk_buff *skb, struct genl_info *info)
 {
         struct ovs_header *ovs_header = info->userhdr;
@@ -505,7 +497,7 @@ static int ovs_packet_cmd_execute(struct sk_buff *skb, struct genl_info *info)
                 packet->protocol = htons(ETH_P_802_2);
 
         /* Build an sw_flow for sending this packet. */
-        flow = ovs_flow_alloc();
+        flow = ovs_flow_alloc(false);
         err = PTR_ERR(flow);
         if (IS_ERR(flow))
                 goto err_kfree_skb;
@@ -641,10 +633,10 @@ static int ovs_flow_cmd_fill_info(struct sw_flow *flow, struct datapath *dp,
         const int skb_orig_len = skb->len;
         struct nlattr *start;
         struct ovs_flow_stats stats;
+        __be16 tcp_flags;
+        unsigned long used;
         struct ovs_header *ovs_header;
         struct nlattr *nla;
-        unsigned long used;
-        u8 tcp_flags;
         int err;
 
         ovs_header = genlmsg_put(skb, portid, seq, &dp_flow_genl_family, flags, cmd);
@@ -673,24 +665,17 @@ static int ovs_flow_cmd_fill_info(struct sw_flow *flow, struct datapath *dp,
 
         nla_nest_end(skb, nla);
 
-        spin_lock_bh(&flow->lock);
-        used = flow->used;
-        stats.n_packets = flow->packet_count;
-        stats.n_bytes = flow->byte_count;
-        tcp_flags = (u8)ntohs(flow->tcp_flags);
-        spin_unlock_bh(&flow->lock);
-
+        ovs_flow_stats_get(flow, &stats, &used, &tcp_flags);
         if (used &&
             nla_put_u64(skb, OVS_FLOW_ATTR_USED, ovs_flow_used_time(used)))
                 goto nla_put_failure;
 
         if (stats.n_packets &&
-            nla_put(skb, OVS_FLOW_ATTR_STATS,
-                    sizeof(struct ovs_flow_stats), &stats))
+            nla_put(skb, OVS_FLOW_ATTR_STATS, sizeof(struct ovs_flow_stats), &stats))
                 goto nla_put_failure;
 
-        if (tcp_flags &&
-            nla_put_u8(skb, OVS_FLOW_ATTR_TCP_FLAGS, tcp_flags))
+        if ((u8)ntohs(tcp_flags) &&
+             nla_put_u8(skb, OVS_FLOW_ATTR_TCP_FLAGS, (u8)ntohs(tcp_flags)))
                 goto nla_put_failure;
 
         /* If OVS_FLOW_ATTR_ACTIONS doesn't fit, skip dumping the actions if
@@ -770,6 +755,7 @@ static int ovs_flow_cmd_new_or_set(struct sk_buff *skb, struct genl_info *info)
         struct datapath *dp;
         struct sw_flow_actions *acts = NULL;
         struct sw_flow_match match;
+        bool exact_5tuple;
         int error;
 
         /* Extract key. */
@@ -778,7 +764,7 @@ static int ovs_flow_cmd_new_or_set(struct sk_buff *skb, struct genl_info *info)
                 goto error;
 
         ovs_match_init(&match, &key, &mask);
-        error = ovs_nla_get_match(&match,
+        error = ovs_nla_get_match(&match, &exact_5tuple,
                                   a[OVS_FLOW_ATTR_KEY], a[OVS_FLOW_ATTR_MASK]);
         if (error)
                 goto error;
@@ -817,12 +803,11 @@ static int ovs_flow_cmd_new_or_set(struct sk_buff *skb, struct genl_info *info)
                         goto err_unlock_ovs;
 
                 /* Allocate flow. */
-                flow = ovs_flow_alloc();
+                flow = ovs_flow_alloc(!exact_5tuple);
                 if (IS_ERR(flow)) {
                         error = PTR_ERR(flow);
                         goto err_unlock_ovs;
                 }
-                clear_stats(flow);
 
                 flow->key = masked_key;
                 flow->unmasked_key = key;
@@ -866,11 +851,8 @@ static int ovs_flow_cmd_new_or_set(struct sk_buff *skb, struct genl_info *info)
                 reply = ovs_flow_cmd_build_info(flow, dp, info, OVS_FLOW_CMD_NEW);
 
                 /* Clear stats. */
-                if (a[OVS_FLOW_ATTR_CLEAR]) {
-                        spin_lock_bh(&flow->lock);
-                        clear_stats(flow);
-                        spin_unlock_bh(&flow->lock);
-                }
+                if (a[OVS_FLOW_ATTR_CLEAR])
+                        ovs_flow_stats_clear(flow);
         }
         ovs_unlock();
 
@@ -908,7 +890,7 @@ static int ovs_flow_cmd_get(struct sk_buff *skb, struct genl_info *info)
         }
 
         ovs_match_init(&match, &key, NULL);
-        err = ovs_nla_get_match(&match, a[OVS_FLOW_ATTR_KEY], NULL);
+        err = ovs_nla_get_match(&match, NULL, a[OVS_FLOW_ATTR_KEY], NULL);
         if (err)
                 return err;
 
@@ -962,7 +944,7 @@ static int ovs_flow_cmd_del(struct sk_buff *skb, struct genl_info *info)
         }
 
         ovs_match_init(&match, &key, NULL);
-        err = ovs_nla_get_match(&match, a[OVS_FLOW_ATTR_KEY], NULL);
+        err = ovs_nla_get_match(&match, NULL, a[OVS_FLOW_ATTR_KEY], NULL);
         if (err)
                 goto unlock;