net/mlx4_en: Change loopback only upon feature change

Currently any change of netdev features results in a call to
mlx4_en_update_loopback_state(). Those calls are unnecessary,
and should be called only upon loopback feature change.

Also moved some of the logic into mlx4_en_update_loopback_state().
Signed-off-by: NIdo Shamay <idos@mellanox.com>
Signed-off-by: NOr Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlx4/en_main.c

@@ -103,6 +103,11 @@ void mlx4_en_update_loopback_state(struct net_device *dev,
 {
 	struct mlx4_en_priv *priv = netdev_priv(dev);
 
+	if (features & NETIF_F_LOOPBACK)
+		priv->ctrl_flags |= cpu_to_be32(MLX4_WQE_CTRL_FORCE_LOOPBACK);
+	else
+		priv->ctrl_flags &= cpu_to_be32(~MLX4_WQE_CTRL_FORCE_LOOPBACK);
+
 	priv->flags &= ~(MLX4_EN_FLAG_RX_FILTER_NEEDED|
 			MLX4_EN_FLAG_ENABLE_HW_LOOPBACK);
 

drivers/net/ethernet/mellanox/mlx4/en_netdev.c

@@ -2210,13 +2210,11 @@ static int mlx4_en_set_features(struct net_device *netdev,
 		en_info(priv, "Turn %s TX vlan strip offload\n",
 			(features & NETIF_F_HW_VLAN_CTAG_TX) ? "ON" : "OFF");
 
-	if (features & NETIF_F_LOOPBACK)
-		priv->ctrl_flags |= cpu_to_be32(MLX4_WQE_CTRL_FORCE_LOOPBACK);
-	else
-		priv->ctrl_flags &=
-			cpu_to_be32(~MLX4_WQE_CTRL_FORCE_LOOPBACK);
-
-	mlx4_en_update_loopback_state(netdev, features);
+	if (DEV_FEATURE_CHANGED(netdev, features, NETIF_F_LOOPBACK)) {
+		en_info(priv, "Turn %s loopback\n",
+			(features & NETIF_F_LOOPBACK) ? "ON" : "OFF");
+		mlx4_en_update_loopback_state(netdev, features);
+	}
 
 	return 0;