Commit d5d75cd6 authored by Stephen Hemminger's avatar Stephen Hemminger Committed by David S. Miller
Browse files

[PKT_SCHED]: netetm: adjust parent qlen when duplicating 



Fix qlen underrun when doing duplication with netem. If netem is used
as leaf discipline, then the parent needs to be tweaked when packets
are duplicated.

Signed-off-by: default avatarStephen Hemminger <shemminger@osdl.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 771018e7

net/sched/sch_api.c

+1 −0
Original line number Diff line number Diff line
@@ -1289,6 +1289,7 @@ static int __init pktsched_init(void) 


subsys_initcall(pktsched_init);



EXPORT_SYMBOL(qdisc_lookup);

EXPORT_SYMBOL(qdisc_get_rtab);

EXPORT_SYMBOL(qdisc_put_rtab);

EXPORT_SYMBOL(register_qdisc);

net/sched/sch_netem.c

+15 −5
Original line number Diff line number Diff line
@@ -206,7 +206,6 @@ static int netem_run(struct Qdisc *sch) 
static int netem_enqueue(struct sk_buff *skb, struct Qdisc *sch)

{

	struct netem_sched_data *q = qdisc_priv(sch);

	struct sk_buff *skb2;

	int ret;



	pr_debug("netem_enqueue skb=%p\n", skb);
@@ -220,11 +219,21 @@ static int netem_enqueue(struct sk_buff *skb, struct Qdisc *sch) 
	}



	/* Random duplication */

	if (q->duplicate && q->duplicate >= get_crandom(&q->dup_cor)

	    && (skb2 = skb_clone(skb, GFP_ATOMIC)) != NULL) {

		pr_debug("netem_enqueue: dup %p\n", skb2);

	if (q->duplicate && q->duplicate >= get_crandom(&q->dup_cor)) {

		struct sk_buff *skb2;



		skb2 = skb_clone(skb, GFP_ATOMIC);

		if (skb2 && netem_delay(sch, skb2) == NET_XMIT_SUCCESS) {

			struct Qdisc *qp;



			/* Since one packet can generate two packets in the

			 * queue, the parent's qlen accounting gets confused,

			 * so fix it.

			 */

			qp = qdisc_lookup(sch->dev, TC_H_MAJ(sch->parent));

			if (qp)

				qp->q.qlen++;



		if (netem_delay(sch, skb2)) {

			sch->q.qlen++;

			sch->bstats.bytes += skb2->len;

			sch->bstats.packets++;
@@ -253,6 +262,7 @@ static int netem_enqueue(struct sk_buff *skb, struct Qdisc *sch) 
	} else

		sch->qstats.drops++;



	pr_debug("netem: enqueue ret %d\n", ret);

	return ret;

}