vlan: clean up vlan_dev_hard_start_xmit()

Clean up vlan_dev_hard_start_xmit() function.

Cc: Benjamin LaHaise <[e-mail]>
Cc: Patrick McHardy <[e-mail]>
Cc: David Miller <[e-mail]>
Signed-off-by: Cong Wang <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

net/8021q/vlan_dev.c

···
 	return rc;
 }
 
+static inline netdev_tx_t vlan_netpoll_send_skb(struct vlan_dev_priv *vlan, struct sk_buff *skb)
+{
+#ifdef CONFIG_NET_POLL_CONTROLLER
+	if (vlan->netpoll)
+		netpoll_send_skb(vlan->netpoll, skb);
+#else
+	BUG();
+#endif
+	return NETDEV_TX_OK;
+}
+
 static netdev_tx_t vlan_dev_hard_start_xmit(struct sk_buff *skb,
 					    struct net_device *dev)
 {
+	struct vlan_dev_priv *vlan = vlan_dev_priv(dev);
 	struct vlan_ethhdr *veth = (struct vlan_ethhdr *)(skb->data);
 	unsigned int len;
 	int ret;
···
 	 * OTHER THINGS LIKE FDDI/TokenRing/802.3 SNAPs...
 	 */
 	if (veth->h_vlan_proto != htons(ETH_P_8021Q) ||
-	    vlan_dev_priv(dev)->flags & VLAN_FLAG_REORDER_HDR) {
+	    vlan->flags & VLAN_FLAG_REORDER_HDR) {
 		u16 vlan_tci;
-		vlan_tci = vlan_dev_priv(dev)->vlan_id;
+		vlan_tci = vlan->vlan_id;
 		vlan_tci |= vlan_dev_get_egress_qos_mask(dev, skb);
 		skb = __vlan_hwaccel_put_tag(skb, vlan_tci);
 	}
 
-	skb->dev = vlan_dev_priv(dev)->real_dev;
+	skb->dev = vlan->real_dev;
 	len = skb->len;
-	if (netpoll_tx_running(dev))
-		return skb->dev->netdev_ops->ndo_start_xmit(skb, skb->dev);
+	if (unlikely(netpoll_tx_running(dev)))
+		return vlan_netpoll_send_skb(vlan, skb);
+
 	ret = dev_queue_xmit(skb);
 
 	if (likely(ret == NET_XMIT_SUCCESS || ret == NET_XMIT_CN)) {
 		struct vlan_pcpu_stats *stats;
 
-		stats = this_cpu_ptr(vlan_dev_priv(dev)->vlan_pcpu_stats);
+		stats = this_cpu_ptr(vlan->vlan_pcpu_stats);
 		u64_stats_update_begin(&stats->syncp);
 		stats->tx_packets++;
 		stats->tx_bytes += len;
 		u64_stats_update_end(&stats->syncp);
 	} else {
-		this_cpu_inc(vlan_dev_priv(dev)->vlan_pcpu_stats->tx_dropped);
+		this_cpu_inc(vlan->vlan_pcpu_stats->tx_dropped);
 	}
 
 	return ret;