From: Cong Wang <xiyou.wangcong@gmail.com>
To: netdev@vger.kernel.org
Cc: jhs@mojatatu.com, jiri@resnulli.us, edumazet@google.com,
gerrard.tai@starlabs.sg, Cong Wang <xiyou.wangcong@gmail.com>
Subject: [Patch net 06/12] codel: remove sch->q.qlen check before qdisc_tree_reduce_backlog()
Date: Thu, 20 Mar 2025 16:25:33 -0700 [thread overview]
Message-ID: <20250320232539.486091-6-xiyou.wangcong@gmail.com> (raw)
In-Reply-To: <20250320232539.486091-1-xiyou.wangcong@gmail.com>
After making all ->qlen_notify() callbacks idempotent, now it is safe to
remove the check of qlen!=0 from both fq_codel_dequeue() and
codel_qdisc_dequeue().
Reported-by: Gerrard Tai <gerrard.tai@starlabs.sg>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
---
net/sched/sch_codel.c | 5 +----
net/sched/sch_fq_codel.c | 6 ++----
2 files changed, 3 insertions(+), 8 deletions(-)
diff --git a/net/sched/sch_codel.c b/net/sched/sch_codel.c
index 81189d02fee7..12dd71139da3 100644
--- a/net/sched/sch_codel.c
+++ b/net/sched/sch_codel.c
@@ -65,10 +65,7 @@ static struct sk_buff *codel_qdisc_dequeue(struct Qdisc *sch)
&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 (q->stats.drop_count && sch->q.qlen) {
+ if (q->stats.drop_count) {
qdisc_tree_reduce_backlog(sch, q->stats.drop_count, q->stats.drop_len);
q->stats.drop_count = 0;
q->stats.drop_len = 0;
diff --git a/net/sched/sch_fq_codel.c b/net/sched/sch_fq_codel.c
index 799f5397ad4c..6c9029f71e88 100644
--- a/net/sched/sch_fq_codel.c
+++ b/net/sched/sch_fq_codel.c
@@ -315,10 +315,8 @@ static struct sk_buff *fq_codel_dequeue(struct Qdisc *sch)
}
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) {
+
+ if (q->cstats.drop_count) {
qdisc_tree_reduce_backlog(sch, q->cstats.drop_count,
q->cstats.drop_len);
q->cstats.drop_count = 0;
--
2.34.1
next prev parent reply other threads:[~2025-03-20 23:25 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-03-20 23:21 [Patch net 00/12] net_sched: make ->qlen_notify() idempotent Cong Wang
2025-03-20 23:25 ` [Patch net 01/12] sch_htb: make htb_qlen_notify() idempotent Cong Wang
2025-03-20 23:25 ` [Patch net 02/12] sch_drr: make drr_qlen_notify() idempotent Cong Wang
2025-03-20 23:25 ` [Patch net 03/12] sch_hfsc: make hfsc_qlen_notify() idempotent Cong Wang
2025-03-20 23:25 ` [Patch net 04/12] sch_qfq: make qfq_qlen_notify() idempotent Cong Wang
2025-03-20 23:25 ` [Patch net 05/12] sch_ets: make est_qlen_notify() idempotent Cong Wang
2025-03-20 23:25 ` Cong Wang [this message]
2025-03-20 23:25 ` [Patch net 07/12] selftests/tc-testing: Add a test case for FQ_CODEL with HTB parent Cong Wang
2025-03-20 23:25 ` [Patch net 08/12] selftests/tc-testing: Add a test case for CODEL " Cong Wang
2025-03-23 22:48 ` Victor Nogueira
2025-03-28 20:35 ` Cong Wang
2025-03-30 21:05 ` Victor Nogueira
2025-03-30 23:32 ` Cong Wang
2025-04-03 0:40 ` Cong Wang
2025-04-03 1:23 ` Victor Nogueira
2025-04-03 19:32 ` Cong Wang
2025-03-20 23:25 ` [Patch net 09/12] selftests/tc-testing: Add a test case for FQ_CODEL with QFQ parent Cong Wang
2025-03-20 23:25 ` [Patch net 10/12] selftests/tc-testing: Add a test case for FQ_CODEL with HFSC parent Cong Wang
2025-03-20 23:25 ` [Patch net 11/12] selftests/tc-testing: Add a test case for FQ_CODEL with DRR parent Cong Wang
2025-03-20 23:25 ` [Patch net 12/12] selftests/tc-testing: Add a test case for FQ_CODEL with ETS parent Cong Wang
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