dev_hard_start_xmit
struct sk_buff *dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev,
skb = dev_hard_start_xmit(skb, dev, txq, &rc);
skb = dev_hard_start_xmit(skb, dev, txq, &ret);
skb = dev_hard_start_xmit(skb, dev, txq, &ret);