Commit 3557619f authored Aug 09, 2011 by Florian Westphal Committed by David S. Miller Aug 09, 2011

net_sched: prio: use qdisc_dequeue_peeked



commit 07bd8df5
(sch_sfq: fix peek() implementation) changed sfq to use generic
peek helper.

This makes HFSC complain about a non-work-conserving child qdisc, if
prio with sfq child is used within hfsc:

hfsc peeks into prio qdisc, which will then peek into sfq.
returned skb is stashed in sch->gso_skb.

Next, hfsc tries to dequeue from prio, but prio will call sfq dequeue
directly, which may return NULL instead of previously peeked-at skb.

Have prio call qdisc_dequeue_peeked, so sfq->dequeue() is
not called in this case.

Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 9be6dd65

net/sched/sch_prio.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -112,7 +112,7 @@ static struct sk_buff prio_dequeue(struct Qdisc sch)

		for (prio = 0; prio < q->bands; prio++) {
		struct Qdisc *qdisc = q->queues[prio];
		struct sk_buff *skb = qdisc->dequeue(qdisc);
		struct sk_buff *skb = qdisc_dequeue_peeked(qdisc);
		if (skb) {
		qdisc_bstats_update(sch, skb);
		sch->q.qlen--;