net_sched: update hierarchical backlog too
When the bottom qdisc decides to, for example, drop some packet,
it calls qdisc_tree_decrease_qlen() to update the queue length
for all its ancestors, we need to update the backlog too to
keep the stats on root qdisc accurate.
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/sch_fq_codel.c b/net/sched/sch_fq_codel.c
index 4c834e9..d3fc8f9 100644
--- a/net/sched/sch_fq_codel.c
+++ b/net/sched/sch_fq_codel.c
@@ -175,7 +175,7 @@
static int fq_codel_enqueue(struct sk_buff *skb, struct Qdisc *sch)
{
struct fq_codel_sched_data *q = qdisc_priv(sch);
- unsigned int idx;
+ unsigned int idx, prev_backlog;
struct fq_codel_flow *flow;
int uninitialized_var(ret);
@@ -203,6 +203,7 @@
if (++sch->q.qlen <= sch->limit)
return NET_XMIT_SUCCESS;
+ prev_backlog = sch->qstats.backlog;
q->drop_overlimit++;
/* Return Congestion Notification only if we dropped a packet
* from this flow.
@@ -211,7 +212,7 @@
return NET_XMIT_CN;
/* As we dropped a packet, better let upper stack know this */
- qdisc_tree_decrease_qlen(sch, 1);
+ qdisc_tree_reduce_backlog(sch, 1, prev_backlog - sch->qstats.backlog);
return NET_XMIT_SUCCESS;
}
@@ -241,6 +242,7 @@
struct fq_codel_flow *flow;
struct list_head *head;
u32 prev_drop_count, prev_ecn_mark;
+ unsigned int prev_backlog;
begin:
head = &q->new_flows;
@@ -259,6 +261,7 @@
prev_drop_count = q->cstats.drop_count;
prev_ecn_mark = q->cstats.ecn_mark;
+ prev_backlog = sch->qstats.backlog;
skb = codel_dequeue(sch, &q->cparams, &flow->cvars, &q->cstats,
dequeue);
@@ -276,12 +279,14 @@
}
qdisc_bstats_update(sch, skb);
flow->deficit -= qdisc_pkt_len(skb);
- /* We cant call qdisc_tree_decrease_qlen() if our qlen is 0,
+ /* We cant call qdisc_tree_reduce_backlog() if our qlen is 0,
* or HTB crashes. Defer it for next round.
*/
if (q->cstats.drop_count && sch->q.qlen) {
- qdisc_tree_decrease_qlen(sch, q->cstats.drop_count);
+ qdisc_tree_reduce_backlog(sch, q->cstats.drop_count,
+ q->cstats.drop_len);
q->cstats.drop_count = 0;
+ q->cstats.drop_len = 0;
}
return skb;
}
@@ -372,11 +377,13 @@
while (sch->q.qlen > sch->limit) {
struct sk_buff *skb = fq_codel_dequeue(sch);
+ q->cstats.drop_len += qdisc_pkt_len(skb);
kfree_skb(skb);
q->cstats.drop_count++;
}
- qdisc_tree_decrease_qlen(sch, q->cstats.drop_count);
+ qdisc_tree_reduce_backlog(sch, q->cstats.drop_count, q->cstats.drop_len);
q->cstats.drop_count = 0;
+ q->cstats.drop_len = 0;
sch_tree_unlock(sch);
return 0;