__qdisc_dequeue_head
skb = __qdisc_dequeue_head(&sch->q);
struct sk_buff *skb = __qdisc_dequeue_head(&sch->q);
struct sk_buff *skb = __qdisc_dequeue_head(qh);
struct sk_buff *skb = __qdisc_dequeue_head(&sch->q);
skb = __qdisc_dequeue_head(&q->l_queue->q);
skb = __qdisc_dequeue_head(&sch->q);
skb = __qdisc_dequeue_head(&q->direct_queue);
skb = __qdisc_dequeue_head(&sch->q);