sch_hfsc: always keep backlog updated

hfsc updates backlog lazily, that is only when we
dump the stats. This is problematic after we begin to
update backlog in qdisc_tree_reduce_backlog().

Reported-by: Stas Nichiporovich <stasn77@gmail.com>
Tested-by: Stas Nichiporovich <stasn77@gmail.com>
Fixes: 2ccccf5fb43f ("net_sched: update hierarchical backlog too")
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 4 insertions, 8 deletions

diff --git a/net/sched/sch_hfsc.c b/net/sched/sch_hfsc.c
index d783d7cc3348..1ac9f9f03fe3 100644
--- a/net/sched/sch_hfsc.c
+++ b/net/sched/sch_hfsc.c
@@ -1529,6 +1529,7 @@ hfsc_reset_qdisc(struct Qdisc *sch)
         q->eligible = RB_ROOT;
         INIT_LIST_HEAD(&q->droplist);
         qdisc_watchdog_cancel(&q->watchdog);
+        sch->qstats.backlog = 0;
         sch->q.qlen = 0;
 }
 
@@ -1559,14 +1560,6 @@ hfsc_dump_qdisc(struct Qdisc *sch, struct sk_buff *skb)
         struct hfsc_sched *q = qdisc_priv(sch);
         unsigned char *b = skb_tail_pointer(skb);
         struct tc_hfsc_qopt qopt;
-        struct hfsc_class *cl;
-        unsigned int i;
-
-        sch->qstats.backlog = 0;
-        for (i = 0; i < q->clhash.hashsize; i++) {
-                hlist_for_each_entry(cl, &q->clhash.hash[i], cl_common.hnode)
-                        sch->qstats.backlog += cl->qdisc->qstats.backlog;
-        }
 
         qopt.defcls = q->defcls;
         if (nla_put(skb, TCA_OPTIONS, sizeof(qopt), &qopt))
@@ -1604,6 +1597,7 @@ hfsc_enqueue(struct sk_buff *skb, struct Qdisc *sch)
         if (cl->qdisc->q.qlen == 1)
                 set_active(cl, qdisc_pkt_len(skb));
 
+        qdisc_qstats_backlog_inc(sch, skb);
         sch->q.qlen++;
 
         return NET_XMIT_SUCCESS;
@@ -1672,6 +1666,7 @@ hfsc_dequeue(struct Qdisc *sch)
 
         qdisc_unthrottled(sch);
         qdisc_bstats_update(sch, skb);
+        qdisc_qstats_backlog_dec(sch, skb);
         sch->q.qlen--;
 
         return skb;
@@ -1695,6 +1690,7 @@ hfsc_drop(struct Qdisc *sch)
                         }
                         cl->qstats.drops++;
                         qdisc_qstats_drop(sch);
+                        sch->qstats.backlog -= len;
                         sch->q.qlen--;
                         return len;
                 }