macvlan: 64 bit rx counters

Use u64_stats_sync infrastructure to implement 64bit stats.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 35 insertions, 21 deletions

diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c
index e096875aa055..e6d626e78515 100644
--- a/drivers/net/macvlan.c
+++ b/drivers/net/macvlan.c
@@ -431,29 +431,38 @@ static void macvlan_uninit(struct net_device *dev)
         free_percpu(vlan->rx_stats);
 }
 
-static struct net_device_stats *macvlan_dev_get_stats(struct net_device *dev)
+static struct rtnl_link_stats64 *macvlan_dev_get_stats64(struct net_device *dev)
 {
-        struct net_device_stats *stats = &dev->stats;
+        struct rtnl_link_stats64 *stats = &dev->stats64;
         struct macvlan_dev *vlan = netdev_priv(dev);
 
-        dev_txq_stats_fold(dev, stats);
+        dev_txq_stats_fold(dev, &dev->stats);
 
         if (vlan->rx_stats) {
-                struct macvlan_rx_stats *p, rx = {0};
+                struct macvlan_rx_stats *p, accum = {0};
+                u64 rx_packets, rx_bytes, rx_multicast;
+                unsigned int start;
                 int i;
 
                 for_each_possible_cpu(i) {
                         p = per_cpu_ptr(vlan->rx_stats, i);
-                        rx.rx_packets += p->rx_packets;
-                        rx.rx_bytes   += p->rx_bytes;
-                        rx.rx_errors  += p->rx_errors;
-                        rx.multicast  += p->multicast;
+                        do {
+                                start = u64_stats_fetch_begin_bh(&p->syncp);
+                                rx_packets      = p->rx_packets;
+                                rx_bytes        = p->rx_bytes;
+                                rx_multicast    = p->rx_multicast;
+                        } while (u64_stats_fetch_retry_bh(&p->syncp, start));
+                        accum.rx_packets        += rx_packets;
+                        accum.rx_bytes          += rx_bytes;
+                        accum.rx_multicast      += rx_multicast;
+                        /* rx_errors is an ulong, updated without syncp protection */
+                        accum.rx_errors         += p->rx_errors;
                 }
-                stats->rx_packets = rx.rx_packets;
-                stats->rx_bytes   = rx.rx_bytes;
-                stats->rx_errors  = rx.rx_errors;
-                stats->rx_dropped = rx.rx_errors;
-                stats->multicast  = rx.multicast;
+                stats->rx_packets = accum.rx_packets;
+                stats->rx_bytes   = accum.rx_bytes;
+                stats->rx_errors  = accum.rx_errors;
+                stats->rx_dropped = accum.rx_errors;
+                stats->multicast  = accum.rx_multicast;
         }
         return stats;
 }
@@ -502,7 +511,7 @@ static const struct net_device_ops macvlan_netdev_ops = {
         .ndo_change_rx_flags    = macvlan_change_rx_flags,
         .ndo_set_mac_address    = macvlan_set_mac_address,
         .ndo_set_multicast_list = macvlan_set_multicast_list,
-        .ndo_get_stats          = macvlan_dev_get_stats,
+        .ndo_get_stats64        = macvlan_dev_get_stats64,
         .ndo_validate_addr      = eth_validate_addr,
 };
 
diff --git a/include/linux/if_macvlan.h b/include/linux/if_macvlan.h
index c26a0e4f0ce8..e24ce6ea1fa3 100644
--- a/include/linux/if_macvlan.h
+++ b/include/linux/if_macvlan.h
@@ -6,6 +6,7 @@
 #include <linux/netdevice.h>
 #include <linux/netlink.h>
 #include <net/netlink.h>
+#include <linux/u64_stats_sync.h>
 
 #if defined(CONFIG_MACVTAP) || defined(CONFIG_MACVTAP_MODULE)
 struct socket *macvtap_get_socket(struct file *);
@@ -27,14 +28,16 @@ struct macvtap_queue;
  *      struct macvlan_rx_stats - MACVLAN percpu rx stats
  *      @rx_packets: number of received packets
  *      @rx_bytes: number of received bytes
- *      @multicast: number of received multicast packets
+ *      @rx_multicast: number of received multicast packets
+ *      @syncp: synchronization point for 64bit counters
  *      @rx_errors: number of errors
  */
 struct macvlan_rx_stats {
-        unsigned long rx_packets;
-        unsigned long rx_bytes;
-        unsigned long multicast;
-        unsigned long rx_errors;
+        u64                     rx_packets;
+        u64                     rx_bytes;
+        u64                     rx_multicast;
+        struct u64_stats_sync   syncp;
+        unsigned long           rx_errors;
 };
 
 struct macvlan_dev {
@@ -56,12 +59,14 @@ static inline void macvlan_count_rx(const struct macvlan_dev *vlan,
 {
         struct macvlan_rx_stats *rx_stats;
 
-        rx_stats = per_cpu_ptr(vlan->rx_stats, smp_processor_id());
+        rx_stats = this_cpu_ptr(vlan->rx_stats);
         if (likely(success)) {
+                u64_stats_update_begin(&rx_stats->syncp);
                 rx_stats->rx_packets++;;
                 rx_stats->rx_bytes += len;
                 if (multicast)
-                        rx_stats->multicast++;
+                        rx_stats->rx_multicast++;
+                u64_stats_update_end(&rx_stats->syncp);
         } else {
                 rx_stats->rx_errors++;
         }