hak5
/
openwrt
mirror of https://github.com/hak5/openwrt.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

kernel: merge a pending fix for HFSC warnings/slowdowns (fixes FS#1136) 

Signed-off-by: Felix Fietkau <nbd@nbd.name>
lede-17.01
Felix Fietkau 2018-03-10 10:09:07 +01:00
parent f609913b5c
commit 60f8d388c6
3 changed files with 89 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

86
target/linux/generic/patches-4.4/620-net_sched-codel-do-not-defer-queue-length-update.patch Normal file
View File

@ -0,0 +1,86 @@
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
@@ -79,11 +79,17 @@ static struct sk_buff *codel_qdisc_deque
skb = codel_dequeue(sch, &q->params, &q->vars, &q->stats, dequeue);
- /* 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
@@ -311,6 +311,21 @@ 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))
@@ -321,15 +336,6 @@ 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;
}

2
target/linux/generic/patches-4.4/660-fq_codel_defaults.patch
View File

@ -1,6 +1,6 @@
--- a/net/sched/sch_fq_codel.c
+++ b/net/sched/sch_fq_codel.c
@@ -471,7 +471,7 @@ static int fq_codel_init(struct Qdisc *s
@@ -477,7 +477,7 @@ static int fq_codel_init(struct Qdisc *s
sch->limit = 10*1024;
q->flows_cnt = 1024;

4
target/linux/generic/patches-4.4/662-use_fq_codel_by_default.patch
View File

@ -13,7 +13,7 @@
device, it has to decide which ones to send first, which ones to
--- a/net/sched/sch_fq_codel.c
+++ b/net/sched/sch_fq_codel.c
@@ -688,7 +688,7 @@ static const struct Qdisc_class_ops fq_c
@@ -694,7 +694,7 @@ static const struct Qdisc_class_ops fq_c
.walk = fq_codel_walk,
};
@ -22,7 +22,7 @@
.cl_ops = &fq_codel_class_ops,
.id = "fq_codel",
.priv_size = sizeof(struct fq_codel_sched_data),
@@ -704,6 +704,7 @@ static struct Qdisc_ops fq_codel_qdisc_o
@@ -710,6 +710,7 @@ static struct Qdisc_ops fq_codel_qdisc_o
.dump_stats = fq_codel_dump_stats,
.owner = THIS_MODULE,
};