diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h
index ed56474cfe3b..f069011524ba 100644
--- a/include/net/sch_generic.h
+++ b/include/net/sch_generic.h
@@ -1106,6 +1106,32 @@ static inline struct sk_buff *qdisc_peek_dequeued(struct Qdisc *sch)
 	return skb;
 }
 
+static inline void qdisc_update_stats_at_dequeue(struct Qdisc *sch,
+						 struct sk_buff *skb)
+{
+	if (qdisc_is_percpu_stats(sch)) {
+		qdisc_qstats_cpu_backlog_dec(sch, skb);
+		qdisc_bstats_cpu_update(sch, skb);
+		qdisc_qstats_atomic_qlen_dec(sch);
+	} else {
+		qdisc_qstats_backlog_dec(sch, skb);
+		qdisc_bstats_update(sch, skb);
+		sch->q.qlen--;
+	}
+}
+
+static inline void qdisc_update_stats_at_enqueue(struct Qdisc *sch,
+						 unsigned int pkt_len)
+{
+	if (qdisc_is_percpu_stats(sch)) {
+		qdisc_qstats_atomic_qlen_inc(sch);
+		this_cpu_add(sch->cpu_qstats->backlog, pkt_len);
+	} else {
+		sch->qstats.backlog += pkt_len;
+		sch->q.qlen++;
+	}
+}
+
 /* use instead of qdisc->dequeue() for all qdiscs queried with ->peek() */
 static inline struct sk_buff *qdisc_dequeue_peeked(struct Qdisc *sch)
 {
diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c
index fb8f138b9776..c126b9f78d6e 100644
--- a/net/sched/sch_api.c
+++ b/net/sched/sch_api.c
@@ -998,6 +998,19 @@ static void notify_and_destroy(struct net *net, struct sk_buff *skb,
 		qdisc_put(old);
 }
 
+static void qdisc_clear_nolock(struct Qdisc *sch)
+{
+	sch->flags &= ~TCQ_F_NOLOCK;
+	if (!(sch->flags & TCQ_F_CPUSTATS))
+		return;
+
+	free_percpu(sch->cpu_bstats);
+	free_percpu(sch->cpu_qstats);
+	sch->cpu_bstats = NULL;
+	sch->cpu_qstats = NULL;
+	sch->flags &= ~TCQ_F_CPUSTATS;
+}
+
 /* Graft qdisc "new" to class "classid" of qdisc "parent" or
  * to device "dev".
  *
@@ -1076,7 +1089,7 @@ static int qdisc_graft(struct net_device *dev, struct Qdisc *parent,
 		/* Only support running class lockless if parent is lockless */
 		if (new && (new->flags & TCQ_F_NOLOCK) &&
 		    parent && !(parent->flags & TCQ_F_NOLOCK))
-			new->flags &= ~TCQ_F_NOLOCK;
+			qdisc_clear_nolock(new);
 
 		if (!cops || !cops->graft)
 			return -EOPNOTSUPP;
diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c
index ddff2952be87..12a6e1a39fa0 100644
--- a/net/sched/sch_generic.c
+++ b/net/sched/sch_generic.c
@@ -629,11 +629,7 @@ static int pfifo_fast_enqueue(struct sk_buff *skb, struct Qdisc *qdisc,
 	if (unlikely(err))
 		return qdisc_drop_cpu(skb, qdisc, to_free);
 
-	qdisc_qstats_atomic_qlen_inc(qdisc);
-	/* Note: skb can not be used after skb_array_produce(),
-	 * so we better not use qdisc_qstats_cpu_backlog_inc()
-	 */
-	this_cpu_add(qdisc->cpu_qstats->backlog, pkt_len);
+	qdisc_update_stats_at_enqueue(qdisc, pkt_len);
 	return NET_XMIT_SUCCESS;
 }
 
@@ -652,9 +648,7 @@ static struct sk_buff *pfifo_fast_dequeue(struct Qdisc *qdisc)
 		skb = __skb_array_consume(q);
 	}
 	if (likely(skb)) {
-		qdisc_qstats_cpu_backlog_dec(qdisc, skb);
-		qdisc_bstats_cpu_update(qdisc, skb);
-		qdisc_qstats_atomic_qlen_dec(qdisc);
+		qdisc_update_stats_at_dequeue(qdisc, skb);
 	} else {
 		qdisc->empty = true;
 	}