net: dummy: use standard dev_lstats_add() and dev_lstats_read()

This driver can simply use the common infrastructure instead
of duplicating it.

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/dummy.c

@@ -51,41 +51,15 @@ static void set_multicast_list(struct net_device *dev)
 {
 }
 
-struct pcpu_dstats {
-	u64			tx_packets;
-	u64			tx_bytes;
-	struct u64_stats_sync	syncp;
-};
-
 static void dummy_get_stats64(struct net_device *dev,
 			      struct rtnl_link_stats64 *stats)
 {
-	int i;
-
-	for_each_possible_cpu(i) {
-		const struct pcpu_dstats *dstats;
-		u64 tbytes, tpackets;
-		unsigned int start;
-
-		dstats = per_cpu_ptr(dev->dstats, i);
-		do {
-			start = u64_stats_fetch_begin_irq(&dstats->syncp);
-			tbytes = dstats->tx_bytes;
-			tpackets = dstats->tx_packets;
-		} while (u64_stats_fetch_retry_irq(&dstats->syncp, start));
-		stats->tx_bytes += tbytes;
-		stats->tx_packets += tpackets;
-	}
+	dev_lstats_read(dev, &stats->tx_packets, &stats->tx_bytes);
 }
 
 static netdev_tx_t dummy_xmit(struct sk_buff *skb, struct net_device *dev)
 {
-	struct pcpu_dstats *dstats = this_cpu_ptr(dev->dstats);
-
-	u64_stats_update_begin(&dstats->syncp);
-	dstats->tx_packets++;
-	dstats->tx_bytes += skb->len;
-	u64_stats_update_end(&dstats->syncp);
+	dev_lstats_add(dev, skb->len);
 
 	skb_tx_timestamp(skb);
 	dev_kfree_skb(skb);
@@ -94,8 +68,8 @@ static netdev_tx_t dummy_xmit(struct sk_buff *skb, struct net_device *dev)
 
 static int dummy_dev_init(struct net_device *dev)
 {
-	dev->dstats = netdev_alloc_pcpu_stats(struct pcpu_dstats);
-	if (!dev->dstats)
+	dev->lstats = netdev_alloc_pcpu_stats(struct pcpu_lstats);
+	if (!dev->lstats)
 		return -ENOMEM;
 
 	return 0;
@@ -103,7 +77,7 @@ static int dummy_dev_init(struct net_device *dev)
 
 static void dummy_dev_uninit(struct net_device *dev)
 {
-	free_percpu(dev->dstats);
+	free_percpu(dev->lstats);
 }
 
 static int dummy_change_carrier(struct net_device *dev, bool new_carrier)