net: sched: remove unnecessary init of qdisc skb head

The memory allocated by using kzallloc_node and kcalloc has been cleared.
Therefore, the structure members of the new qdisc are 0. So there's no
need to explicitly assign a value of 0.

Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/sch_generic.h

@@ -940,13 +940,6 @@ static inline void qdisc_purge_queue(struct Qdisc *sch)
 	qdisc_tree_reduce_backlog(sch, qlen, backlog);
 }
 
-static inline void qdisc_skb_head_init(struct qdisc_skb_head *qh)
-{
-	qh->head = NULL;
-	qh->tail = NULL;
-	qh->qlen = 0;
-}
-
 static inline void __qdisc_enqueue_tail(struct sk_buff *skb,
 					struct qdisc_skb_head *qh)
 {

net/sched/sch_generic.c

@@ -941,7 +941,6 @@ struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue,
 		goto errout;
 	__skb_queue_head_init(&sch->gso_skb);
 	__skb_queue_head_init(&sch->skb_bad_txq);
-	qdisc_skb_head_init(&sch->q);
 	gnet_stats_basic_sync_init(&sch->bstats);
 	spin_lock_init(&sch->q.lock);
 

net/sched/sch_htb.c

@@ -1104,8 +1104,6 @@ static int htb_init(struct Qdisc *sch, struct nlattr *opt,
 	if (err < 0)
 		goto err_free_direct_qdiscs;
 
-	qdisc_skb_head_init(&q->direct_queue);
-
 	if (tb[TCA_HTB_DIRECT_QLEN])
 		q->direct_qlen = nla_get_u32(tb[TCA_HTB_DIRECT_QLEN]);
 	else