IB/ipoib: Add multicast packets statistics

Update the multicast counter when multicast packets are received and
provide this information through ethtool support.

Signed-off-by: Alex Vesker <valex@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>

drivers/infiniband/ulp/ipoib/ipoib_ethtool.c

@@ -52,7 +52,8 @@ static const struct ipoib_stats ipoib_gstrings_stats[] = {
 	IPOIB_NETDEV_STAT(tx_bytes),
 	IPOIB_NETDEV_STAT(tx_errors),
 	IPOIB_NETDEV_STAT(rx_dropped),
-	IPOIB_NETDEV_STAT(tx_dropped)
+	IPOIB_NETDEV_STAT(tx_dropped),
+	IPOIB_NETDEV_STAT(multicast),
 };
 
 #define IPOIB_GLOBAL_STATS_LEN	ARRAY_SIZE(ipoib_gstrings_stats)

drivers/infiniband/ulp/ipoib/ipoib_ib.c

@@ -256,6 +256,8 @@ static void ipoib_ib_handle_rx_wc(struct net_device *dev, struct ib_wc *wc)
 
 	++dev->stats.rx_packets;
 	dev->stats.rx_bytes += skb->len;
+	if (skb->pkt_type == PACKET_MULTICAST)
+		dev->stats.multicast++;
 
 	skb->dev = dev;
 	if ((dev->features & NETIF_F_RXCSUM) &&