vlan: 64 bit rx counters

Use u64_stats_sync infrastructure to implement 64bit rx stats.

(tx stats are addressed later)

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>
diff --git a/net/8021q/vlan_dev.c b/net/8021q/vlan_dev.c
index 5298426..c6456cb 100644
--- a/net/8021q/vlan_dev.c
+++ b/net/8021q/vlan_dev.c
@@ -166,6 +166,7 @@
 
 	rx_stats = per_cpu_ptr(vlan_dev_info(skb->dev)->vlan_rx_stats,
 			       smp_processor_id());
+	u64_stats_update_begin(&rx_stats->syncp);
 	rx_stats->rx_packets++;
 	rx_stats->rx_bytes += skb->len;
 
@@ -182,7 +183,7 @@
 		break;
 
 	case PACKET_MULTICAST:
-		rx_stats->multicast++;
+		rx_stats->rx_multicast++;
 		break;
 
 	case PACKET_OTHERHOST:
@@ -197,6 +198,7 @@
 	default:
 		break;
 	}
+	u64_stats_update_end(&rx_stats->syncp);
 
 	vlan_set_encap_proto(skb, vhdr);
 
@@ -801,27 +803,37 @@
 	return dev_ethtool_get_flags(vlan->real_dev);
 }
 
-static struct net_device_stats *vlan_dev_get_stats(struct net_device *dev)
+static struct rtnl_link_stats64 *vlan_dev_get_stats64(struct net_device *dev)
 {
-	struct net_device_stats *stats = &dev->stats;
+	struct rtnl_link_stats64 *stats = &dev->stats64;
 
-	dev_txq_stats_fold(dev, stats);
+	dev_txq_stats_fold(dev, &dev->stats);
 
 	if (vlan_dev_info(dev)->vlan_rx_stats) {
-		struct vlan_rx_stats *p, rx = {0};
+		struct vlan_rx_stats *p, accum = {0};
 		int i;
 
 		for_each_possible_cpu(i) {
+			u64 rxpackets, rxbytes, rxmulticast;
+			unsigned int start;
+
 			p = per_cpu_ptr(vlan_dev_info(dev)->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);
+				rxpackets	= p->rx_packets;
+				rxbytes		= p->rx_bytes;
+				rxmulticast	= p->rx_multicast;
+			} while (u64_stats_fetch_retry_bh(&p->syncp, start));
+			accum.rx_packets += rxpackets;
+			accum.rx_bytes   += rxbytes;
+			accum.rx_multicast += rxmulticast;
+			/* rx_errors is an ulong, not protected by syncp */
+			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->multicast  = rx.multicast;
+		stats->rx_packets = accum.rx_packets;
+		stats->rx_bytes   = accum.rx_bytes;
+		stats->rx_errors  = accum.rx_errors;
+		stats->multicast  = accum.rx_multicast;
 	}
 	return stats;
 }
@@ -848,7 +860,7 @@
 	.ndo_change_rx_flags	= vlan_dev_change_rx_flags,
 	.ndo_do_ioctl		= vlan_dev_ioctl,
 	.ndo_neigh_setup	= vlan_dev_neigh_setup,
-	.ndo_get_stats		= vlan_dev_get_stats,
+	.ndo_get_stats64	= vlan_dev_get_stats64,
 #if defined(CONFIG_FCOE) || defined(CONFIG_FCOE_MODULE)
 	.ndo_fcoe_ddp_setup	= vlan_dev_fcoe_ddp_setup,
 	.ndo_fcoe_ddp_done	= vlan_dev_fcoe_ddp_done,
@@ -872,7 +884,7 @@
 	.ndo_change_rx_flags	= vlan_dev_change_rx_flags,
 	.ndo_do_ioctl		= vlan_dev_ioctl,
 	.ndo_neigh_setup	= vlan_dev_neigh_setup,
-	.ndo_get_stats		= vlan_dev_get_stats,
+	.ndo_get_stats64	= vlan_dev_get_stats64,
 #if defined(CONFIG_FCOE) || defined(CONFIG_FCOE_MODULE)
 	.ndo_fcoe_ddp_setup	= vlan_dev_fcoe_ddp_setup,
 	.ndo_fcoe_ddp_done	= vlan_dev_fcoe_ddp_done,
@@ -897,7 +909,7 @@
 	.ndo_change_rx_flags	= vlan_dev_change_rx_flags,
 	.ndo_do_ioctl		= vlan_dev_ioctl,
 	.ndo_neigh_setup	= vlan_dev_neigh_setup,
-	.ndo_get_stats		= vlan_dev_get_stats,
+	.ndo_get_stats64	= vlan_dev_get_stats64,
 #if defined(CONFIG_FCOE) || defined(CONFIG_FCOE_MODULE)
 	.ndo_fcoe_ddp_setup	= vlan_dev_fcoe_ddp_setup,
 	.ndo_fcoe_ddp_done	= vlan_dev_fcoe_ddp_done,
@@ -922,7 +934,7 @@
 	.ndo_change_rx_flags	= vlan_dev_change_rx_flags,
 	.ndo_do_ioctl		= vlan_dev_ioctl,
 	.ndo_neigh_setup	= vlan_dev_neigh_setup,
-	.ndo_get_stats		= vlan_dev_get_stats,
+	.ndo_get_stats64	= vlan_dev_get_stats64,
 #if defined(CONFIG_FCOE) || defined(CONFIG_FCOE_MODULE)
 	.ndo_fcoe_ddp_setup	= vlan_dev_fcoe_ddp_setup,
 	.ndo_fcoe_ddp_done	= vlan_dev_fcoe_ddp_done,