[PATCH 4.4 049/114] sch_red: update backlog as well

[Greg Kroah-Hartman]

4.4-stable review patch.  If anyone has any objections, please let me know.

------------------

[ Upstream commit d7f4f332f082c4d4ba53582f902ed6b44fd6f45e ]

Fixes: 2ccccf5fb43f ("net_sched: update hierarchical backlog too")
Cc: Jamal Hadi Salim <jhs@xxxxxxxxxxxx>
Signed-off-by: Cong Wang <xiyou.wangcong@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 net/sched/sch_red.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/net/sched/sch_red.c b/net/sched/sch_red.c
index 0505b8408c8b..4bf2b599ef98 100644
--- a/net/sched/sch_red.c
+++ b/net/sched/sch_red.c
@@ -97,6 +97,7 @@ static int red_enqueue(struct sk_buff *skb, struct Qdisc *sch)
 
 	ret = qdisc_enqueue(skb, child);
 	if (likely(ret == NET_XMIT_SUCCESS)) {
+		qdisc_qstats_backlog_inc(sch, skb);
 		sch->q.qlen++;
 	} else if (net_xmit_drop_count(ret)) {
 		q->stats.pdrop++;
@@ -118,6 +119,7 @@ static struct sk_buff *red_dequeue(struct Qdisc *sch)
 	skb = child->dequeue(child);
 	if (skb) {
 		qdisc_bstats_update(sch, skb);
+		qdisc_qstats_backlog_dec(sch, skb);
 		sch->q.qlen--;
 	} else {
 		if (!red_is_idling(&q->vars))
@@ -143,6 +145,7 @@ static unsigned int red_drop(struct Qdisc *sch)
 	if (child->ops->drop && (len = child->ops->drop(child)) > 0) {
 		q->stats.other++;
 		qdisc_qstats_drop(sch);
+		sch->qstats.backlog -= len;
 		sch->q.qlen--;
 		return len;
 	}
@@ -158,6 +161,7 @@ static void red_reset(struct Qdisc *sch)
 	struct red_sched_data *q = qdisc_priv(sch);
 
 	qdisc_reset(q->qdisc);
+	sch->qstats.backlog = 0;
 	sch->q.qlen = 0;
 	red_restart(&q->vars);
 }
-- 
2.17.1