pkt_sched: Add qdisc->ops->peek() implementation.

Add qdisc->ops->peek() implementation for work-conserving qdiscs.
With feedback from Patrick McHardy.

Signed-off-by: Jarek Poplawski <jarkao2@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 9 insertions, 0 deletions

diff --git a/net/sched/sch_red.c b/net/sched/sch_red.c
index 5da05839e225..7abc51454c2d 100644
--- a/net/sched/sch_red.c
+++ b/net/sched/sch_red.c
@@ -140,6 +140,14 @@ static struct sk_buff * red_dequeue(struct Qdisc* sch)
         return skb;
 }
 
+static struct sk_buff * red_peek(struct Qdisc* sch)
+{
+        struct red_sched_data *q = qdisc_priv(sch);
+        struct Qdisc *child = q->qdisc;
+
+        return child->ops->peek(child);
+}
+
 static unsigned int red_drop(struct Qdisc* sch)
 {
         struct red_sched_data *q = qdisc_priv(sch);
@@ -361,6 +369,7 @@ static struct Qdisc_ops red_qdisc_ops __read_mostly = {
         .cl_ops         =       &red_class_ops,
         .enqueue        =       red_enqueue,
         .dequeue        =       red_dequeue,
+        .peek           =       red_peek,
         .requeue        =       red_requeue,
         .drop           =       red_drop,
         .init           =       red_init,