pkt_sched: Add peek emulation for non-work-conserving qdiscs.
This patch adds qdisc_peek_dequeued() wrapper to emulate peek method
with qdisc->dequeue() and storing "peeked" skb in qdisc->gso_skb until
dequeuing. This is mainly for compatibility reasons not to break some
strange configs because peeking is expected for non-work-conserving
parent qdiscs to query work-conserving child qdiscs.
This implementation requires using qdisc_dequeue_peeked() wrapper
instead of directly calling qdisc->dequeue() for all qdiscs ever
querried with qdisc->ops->peek() or qdisc_peek_dequeued().
Signed-off-by: Jarek Poplawski <jarkao2@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/sch_netem.c b/net/sched/sch_netem.c
index 74fbdb5..3080bd6 100644
--- a/net/sched/sch_netem.c
+++ b/net/sched/sch_netem.c
@@ -290,8 +290,8 @@
/* if more time remaining? */
if (cb->time_to_send <= now) {
- skb = q->qdisc->dequeue(q->qdisc);
- if (!skb)
+ skb = qdisc_dequeue_peeked(q->qdisc);
+ if (unlikely(!skb))
return NULL;
pr_debug("netem_dequeue: return skb=%p\n", skb);
@@ -714,6 +714,7 @@
.priv_size = sizeof(struct netem_sched_data),
.enqueue = netem_enqueue,
.dequeue = netem_dequeue,
+ .peek = qdisc_peek_dequeued,
.requeue = netem_requeue,
.drop = netem_drop,
.init = netem_init,