vxlan: Fix racy device stats updates.

VXLAN devices update their stats locklessly. Therefore these counters
should either be stored in per-cpu data structures or the updates
should be done using atomic increments.

Since the net_device_core_stats infrastructure is already used in
vxlan_rcv(), use it for the other rx_dropped and tx_dropped counter
updates. Update the other counters atomically using DEV_STATS_INC().

Fixes: d342894c5d2f ("vxlan: virtual extensible lan")
Signed-off-by: Guillaume Nault <gnault@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/vxlan/vxlan_core.c b/drivers/net/vxlan/vxlan_core.c
index ba319fc219571975597bf7aad3d913e77dac6898..0cd9e44c7be85face1fd3e0eeb43c432b38f4932 100644 (file)
--- a/drivers/net/vxlan/vxlan_core.c
+++ b/drivers/net/vxlan/vxlan_core.c
@@ -1766,8 +1766,8 @@ static int vxlan_rcv(struct sock *sk, struct sk_buff *skb)
        skb_reset_network_header(skb);
 
        if (!vxlan_ecn_decapsulate(vs, oiph, skb)) {
-               ++vxlan->dev->stats.rx_frame_errors;
-               ++vxlan->dev->stats.rx_errors;
+               DEV_STATS_INC(vxlan->dev, rx_frame_errors);
+               DEV_STATS_INC(vxlan->dev, rx_errors);
                vxlan_vnifilter_count(vxlan, vni, vninode,
                                      VXLAN_VNI_STATS_RX_ERRORS, 0);
                goto drop;
@@ -1837,7 +1837,7 @@ static int arp_reduce(struct net_device *dev, struct sk_buff *skb, __be32 vni)
                goto out;
 
        if (!pskb_may_pull(skb, arp_hdr_len(dev))) {
-               dev->stats.tx_dropped++;
+               dev_core_stats_tx_dropped_inc(dev);
                goto out;
        }
        parp = arp_hdr(skb);
@@ -1893,7 +1893,7 @@ static int arp_reduce(struct net_device *dev, struct sk_buff *skb, __be32 vni)
                reply->pkt_type = PACKET_HOST;
 
                if (netif_rx(reply) == NET_RX_DROP) {
-                       dev->stats.rx_dropped++;
+                       dev_core_stats_rx_dropped_inc(dev);
                        vxlan_vnifilter_count(vxlan, vni, NULL,
                                              VXLAN_VNI_STATS_RX_DROPS, 0);
                }
@@ -2052,7 +2052,7 @@ static int neigh_reduce(struct net_device *dev, struct sk_buff *skb, __be32 vni)
                        goto out;
 
                if (netif_rx(reply) == NET_RX_DROP) {
-                       dev->stats.rx_dropped++;
+                       dev_core_stats_rx_dropped_inc(dev);
                        vxlan_vnifilter_count(vxlan, vni, NULL,
                                              VXLAN_VNI_STATS_RX_DROPS, 0);
                }
@@ -2263,7 +2263,7 @@ static void vxlan_encap_bypass(struct sk_buff *skb, struct vxlan_dev *src_vxlan,
                                      len);
        } else {
 drop:
-               dev->stats.rx_dropped++;
+               dev_core_stats_rx_dropped_inc(dev);
                vxlan_vnifilter_count(dst_vxlan, vni, NULL,
                                      VXLAN_VNI_STATS_RX_DROPS, 0);
        }
@@ -2295,7 +2295,7 @@ static int encap_bypass_if_local(struct sk_buff *skb, struct net_device *dev,
                                           addr_family, dst_port,
                                           vxlan->cfg.flags);
                if (!dst_vxlan) {
-                       dev->stats.tx_errors++;
+                       DEV_STATS_INC(dev, tx_errors);
                        vxlan_vnifilter_count(vxlan, vni, NULL,
                                              VXLAN_VNI_STATS_TX_ERRORS, 0);
                        kfree_skb(skb);
@@ -2559,7 +2559,7 @@ out_unlock:
        return;
 
 drop:
-       dev->stats.tx_dropped++;
+       dev_core_stats_tx_dropped_inc(dev);
        vxlan_vnifilter_count(vxlan, vni, NULL, VXLAN_VNI_STATS_TX_DROPS, 0);
        dev_kfree_skb(skb);
        return;
@@ -2567,11 +2567,11 @@ drop:
 tx_error:
        rcu_read_unlock();
        if (err == -ELOOP)
-               dev->stats.collisions++;
+               DEV_STATS_INC(dev, collisions);
        else if (err == -ENETUNREACH)
-               dev->stats.tx_carrier_errors++;
+               DEV_STATS_INC(dev, tx_carrier_errors);
        dst_release(ndst);
-       dev->stats.tx_errors++;
+       DEV_STATS_INC(dev, tx_errors);
        vxlan_vnifilter_count(vxlan, vni, NULL, VXLAN_VNI_STATS_TX_ERRORS, 0);
        kfree_skb(skb);
 }
@@ -2604,7 +2604,7 @@ static void vxlan_xmit_nh(struct sk_buff *skb, struct net_device *dev,
        return;
 
 drop:
-       dev->stats.tx_dropped++;
+       dev_core_stats_tx_dropped_inc(dev);
        vxlan_vnifilter_count(netdev_priv(dev), vni, NULL,
                              VXLAN_VNI_STATS_TX_DROPS, 0);
        dev_kfree_skb(skb);
@@ -2642,7 +2642,7 @@ static netdev_tx_t vxlan_xmit_nhid(struct sk_buff *skb, struct net_device *dev,
        return NETDEV_TX_OK;
 
 drop:
-       dev->stats.tx_dropped++;
+       dev_core_stats_tx_dropped_inc(dev);
        vxlan_vnifilter_count(netdev_priv(dev), vni, NULL,
                              VXLAN_VNI_STATS_TX_DROPS, 0);
        dev_kfree_skb(skb);
@@ -2739,7 +2739,7 @@ static netdev_tx_t vxlan_xmit(struct sk_buff *skb, struct net_device *dev)
                            !is_multicast_ether_addr(eth->h_dest))
                                vxlan_fdb_miss(vxlan, eth->h_dest);
 
-                       dev->stats.tx_dropped++;
+                       dev_core_stats_tx_dropped_inc(dev);
                        vxlan_vnifilter_count(vxlan, vni, NULL,
                                              VXLAN_VNI_STATS_TX_DROPS, 0);
                        kfree_skb(skb);