mirror of https://github.com/hak5/openwrt.git
87 lines
3.0 KiB
Diff
87 lines
3.0 KiB
Diff
|
From: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
|
||
|
|
Date: Mon, 21 Aug 2017 11:14:14 +0300
|
||
|
|
Subject: [PATCH] net_sched/codel: do not defer queue length update
|
||
|
|
|
||
|
|
When codel wants to drop last packet in ->dequeue() it cannot call
|
||
|
|
qdisc_tree_reduce_backlog() right away - it will notify parent qdisc
|
||
|
|
about zero qlen and HTB/HFSC will deactivate class. The same class will
|
||
|
|
be deactivated second time by caller of ->dequeue(). Currently codel and
|
||
|
|
fq_codel defer update. This triggers warning in HFSC when it's qlen != 0
|
||
|
|
but there is no active classes.
|
||
|
|
|
||
|
|
This patch update parent queue length immediately: just temporary increase
|
||
|
|
qlen around qdisc_tree_reduce_backlog() to prevent first class deactivation
|
||
|
|
if we have skb to return.
|
||
|
|
|
||
|
|
This might open another problem in HFSC - now operation peek could fail and
|
||
|
|
deactivate parent class.
|
||
|
|
|
||
|
|
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
|
||
|
|
Link: https://bugzilla.kernel.org/show_bug.cgi?id=109581
|
||
|
|
---
|
||
|
|
|
||
|
|
--- a/net/sched/sch_codel.c
|
||
|
|
+++ b/net/sched/sch_codel.c
|
||
|
|
@@ -95,11 +95,17 @@ static struct sk_buff *codel_qdisc_deque
|
||
|
|
&q->stats, qdisc_pkt_len, codel_get_enqueue_time,
|
||
|
|
drop_func, dequeue_func);
|
||
|
|
|
||
|
|
- /* We cant call qdisc_tree_reduce_backlog() if our qlen is 0,
|
||
|
|
- * or HTB crashes. Defer it for next round.
|
||
|
|
+ /* If our qlen is 0 qdisc_tree_reduce_backlog() will deactivate
|
||
|
|
+ * parent class, dequeue in parent qdisc will do the same if we
|
||
|
|
+ * return skb. Temporary increment qlen if we have skb.
|
||
|
|
*/
|
||
|
|
- if (q->stats.drop_count && sch->q.qlen) {
|
||
|
|
- qdisc_tree_reduce_backlog(sch, q->stats.drop_count, q->stats.drop_len);
|
||
|
|
+ if (q->stats.drop_count) {
|
||
|
|
+ if (skb)
|
||
|
|
+ sch->q.qlen++;
|
||
|
|
+ qdisc_tree_reduce_backlog(sch, q->stats.drop_count,
|
||
|
|
+ q->stats.drop_len);
|
||
|
|
+ if (skb)
|
||
|
|
+ sch->q.qlen--;
|
||
|
|
q->stats.drop_count = 0;
|
||
|
|
q->stats.drop_len = 0;
|
||
|
|
}
|
||
|
|
--- a/net/sched/sch_fq_codel.c
|
||
|
|
+++ b/net/sched/sch_fq_codel.c
|
||
|
|
@@ -316,6 +316,21 @@ begin:
|
||
|
|
flow->dropped += q->cstats.drop_count - prev_drop_count;
|
||
|
|
flow->dropped += q->cstats.ecn_mark - prev_ecn_mark;
|
||
|
|
|
||
|
|
+ /* If our qlen is 0 qdisc_tree_reduce_backlog() will deactivate
|
||
|
|
+ * parent class, dequeue in parent qdisc will do the same if we
|
||
|
|
+ * return skb. Temporary increment qlen if we have skb.
|
||
|
|
+ */
|
||
|
|
+ if (q->cstats.drop_count) {
|
||
|
|
+ if (skb)
|
||
|
|
+ sch->q.qlen++;
|
||
|
|
+ qdisc_tree_reduce_backlog(sch, q->cstats.drop_count,
|
||
|
|
+ q->cstats.drop_len);
|
||
|
|
+ if (skb)
|
||
|
|
+ sch->q.qlen--;
|
||
|
|
+ q->cstats.drop_count = 0;
|
||
|
|
+ q->cstats.drop_len = 0;
|
||
|
|
+ }
|
||
|
|
+
|
||
|
|
if (!skb) {
|
||
|
|
/* force a pass through old_flows to prevent starvation */
|
||
|
|
if ((head == &q->new_flows) && !list_empty(&q->old_flows))
|
||
|
|
@@ -326,15 +341,6 @@ begin:
|
||
|
|
}
|
||
|
|
qdisc_bstats_update(sch, skb);
|
||
|
|
flow->deficit -= qdisc_pkt_len(skb);
|
||
|
|
- /* 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_reduce_backlog(sch, q->cstats.drop_count,
|
||
|
|
- q->cstats.drop_len);
|
||
|
|
- q->cstats.drop_count = 0;
|
||
|
|
- q->cstats.drop_len = 0;
|
||
|
|
- }
|
||
|
|
return skb;
|
||
|
|
}
|
||
|
|
|