[PKT_SCHED]: Delay scheduler should retry if requeue fails.

If delay scheduler decides not to send the packet right away, it requeues
it.  If the requeue fails, it should go and look again rather than waking
up prematurely.

Same patch should apply to both 2.6 and 2.4
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@redhat.com>

net/sched/sch_delay.c

@@ -104,8 +104,10 @@ static unsigned int dly_drop(struct Qdisc *sch)
 static struct sk_buff *dly_dequeue(struct Qdisc *sch)
 {
 	struct dly_sched_data *q = (struct dly_sched_data *)sch->data;
-	struct sk_buff *skb = q->qdisc->dequeue(q->qdisc);
+	struct sk_buff *skb;
 
+ retry:
+	skb = q->qdisc->dequeue(q->qdisc);
 	if (skb) {
 		struct dly_skb_cb *cb = (struct dly_skb_cb *)skb->cb;
 		psched_time_t now;
@@ -120,6 +122,12 @@ static struct sk_buff *dly_dequeue(struct Qdisc *sch)
 			return skb;
 		}
 
+		if (q->qdisc->ops->requeue(skb, q->qdisc) != NET_XMIT_SUCCESS) {
+			sch->q.qlen--;
+			sch->stats.drops++;
+			goto retry;
+		}
+
 		if (!netif_queue_stopped(sch->dev)) {
 			long delay = PSCHED_US2JIFFIE(diff);
 			if (delay <= 0)
@@ -127,10 +135,6 @@ static struct sk_buff *dly_dequeue(struct Qdisc *sch)
 			mod_timer(&q->timer, jiffies+delay);
 		}
 
-		if (q->qdisc->ops->requeue(skb, q->qdisc) != NET_XMIT_SUCCESS) {
-			sch->q.qlen--;
-			sch->stats.drops++;
-		}
 		sch->flags |= TCQ_F_THROTTLED;
 	}
 	return NULL;