veth: use standard dev_lstats_add() and dev_lstats_read()

This cleanup will ease u64_stats_t adoption in a single location.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/veth.c

@@ -260,14 +260,8 @@ static netdev_tx_t veth_xmit(struct sk_buff *skb, struct net_device *dev)
 
 	skb_tx_timestamp(skb);
 	if (likely(veth_forward_skb(rcv, skb, rq, rcv_xdp) == NET_RX_SUCCESS)) {
-		if (!rcv_xdp) {
-			struct pcpu_lstats *stats = this_cpu_ptr(dev->lstats);
-
-			u64_stats_update_begin(&stats->syncp);
-			stats->bytes += length;
-			stats->packets++;
-			u64_stats_update_end(&stats->syncp);
-		}
+		if (!rcv_xdp)
+			dev_lstats_add(dev, length);
 	} else {
 drop:
 		atomic64_inc(&priv->dropped);
@@ -281,26 +275,11 @@ static netdev_tx_t veth_xmit(struct sk_buff *skb, struct net_device *dev)
 	return NETDEV_TX_OK;
 }
 
-static u64 veth_stats_tx(struct pcpu_lstats *result, struct net_device *dev)
+static u64 veth_stats_tx(struct net_device *dev, u64 *packets, u64 *bytes)
 {
 	struct veth_priv *priv = netdev_priv(dev);
-	int cpu;
-
-	result->packets = 0;
-	result->bytes = 0;
-	for_each_possible_cpu(cpu) {
-		struct pcpu_lstats *stats = per_cpu_ptr(dev->lstats, cpu);
-		u64 packets, bytes;
-		unsigned int start;
 
-		do {
-			start = u64_stats_fetch_begin_irq(&stats->syncp);
-			packets = stats->packets;
-			bytes = stats->bytes;
-		} while (u64_stats_fetch_retry_irq(&stats->syncp, start));
-		result->packets += packets;
-		result->bytes += bytes;
-	}
+	dev_lstats_read(dev, packets, bytes);
 	return atomic64_read(&priv->dropped);
 }
 
@@ -335,11 +314,11 @@ static void veth_get_stats64(struct net_device *dev,
 	struct veth_priv *priv = netdev_priv(dev);
 	struct net_device *peer;
 	struct veth_rq_stats rx;
-	struct pcpu_lstats tx;
+	u64 packets, bytes;
 
-	tot->tx_dropped = veth_stats_tx(&tx, dev);
-	tot->tx_bytes = tx.bytes;
-	tot->tx_packets = tx.packets;
+	tot->tx_dropped = veth_stats_tx(dev, &packets, &bytes);
+	tot->tx_bytes = bytes;
+	tot->tx_packets = packets;
 
 	veth_stats_rx(&rx, dev);
 	tot->rx_dropped = rx.xdp_drops;
@@ -349,9 +328,9 @@ static void veth_get_stats64(struct net_device *dev,
 	rcu_read_lock();
 	peer = rcu_dereference(priv->peer);
 	if (peer) {
-		tot->rx_dropped += veth_stats_tx(&tx, peer);
-		tot->rx_bytes += tx.bytes;
-		tot->rx_packets += tx.packets;
+		tot->rx_dropped += veth_stats_tx(peer, &packets, &bytes);
+		tot->rx_bytes += bytes;
+		tot->rx_packets += packets;
 
 		veth_stats_rx(&rx, peer);
 		tot->tx_bytes += rx.xdp_bytes;