[Patch net] net_sched: keep backlog updated with qlen

[Cong Wang]

For gso_skb we only update qlen, backlog should be updated too.

Note, it is correct to just update these stats at one layer,
because the gso_skb is cached there.

Reported-by: Stas Nichiporovich <stas...@gmail.com>
Fixes: 2ccccf5fb43f ("net_sched: update hierarchical backlog too")
Cc: Jamal Hadi Salim <j...@mojatatu.com>
Signed-off-by: Cong Wang <xiyou.wangc...@gmail.com>
---
 include/net/sch_generic.h | 5 ++++-
 net/sched/sch_generic.c   | 2 ++
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h
index a1fd76c..6803af1 100644
--- a/include/net/sch_generic.h
+++ b/include/net/sch_generic.h
@@ -691,9 +691,11 @@ static inline struct sk_buff *qdisc_peek_dequeued(struct 
Qdisc *sch)
        /* we can reuse ->gso_skb because peek isn't called for root qdiscs */
        if (!sch->gso_skb) {
                sch->gso_skb = sch->dequeue(sch);
-               if (sch->gso_skb)
+               if (sch->gso_skb) {
                        /* it's still part of the queue */
+                       qdisc_qstats_backlog_inc(sch, sch->gso_skb);
                        sch->q.qlen++;
+               }
        }
 
        return sch->gso_skb;
@@ -706,6 +708,7 @@ static inline struct sk_buff *qdisc_dequeue_peeked(struct 
Qdisc *sch)
 
        if (skb) {
                sch->gso_skb = NULL;
+               qdisc_qstats_backlog_dec(sch, skb);
                sch->q.qlen--;
        } else {
                skb = sch->dequeue(sch);
diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c
index 269dd71..f9e0e9c 100644
--- a/net/sched/sch_generic.c
+++ b/net/sched/sch_generic.c
@@ -49,6 +49,7 @@ static inline int dev_requeue_skb(struct sk_buff *skb, struct 
Qdisc *q)
 {
        q->gso_skb = skb;
        q->qstats.requeues++;
+       qdisc_qstats_backlog_inc(q, skb);
        q->q.qlen++;    /* it's still part of the queue */
        __netif_schedule(q);
 
@@ -92,6 +93,7 @@ static struct sk_buff *dequeue_skb(struct Qdisc *q, bool 
*validate,
                txq = skb_get_tx_queue(txq->dev, skb);
                if (!netif_xmit_frozen_or_stopped(txq)) {
                        q->gso_skb = NULL;
+                       qdisc_qstats_backlog_dec(q, skb);
                        q->q.qlen--;
                } else
                        skb = NULL;
-- 
2.1.0