Commit 02201464 authored by Jarek Poplawski's avatar Jarek Poplawski Committed by David S. Miller
Browse files

sch_netem: Remove classful functionality 



Patrick McHardy noticed that: "a lot of the functionality of netem
requires the inner tfifo anyways and rate-limiting is usually done
on top of netem. So I would suggest so either hard-wire the tfifo
qdisc or at least make the assumption that inner qdiscs are
work-conserving.", and later: "- a lot of other qdiscs still don't
work as inner qdiscs of netem [...]".

So, according to his suggestion, this patch removes classful options
of netem. The main reason of this change is to remove ops->requeue()
method, which is currently used only by netem.

Signed-off-by: default avatarJarek Poplawski <jarkao2@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent ae27e98a

net/sched/sch_netem.c

+0 −87
Original line number Diff line number Diff line
@@ -622,95 +622,8 @@ nla_put_failure: 
	return -1;

}



static int netem_dump_class(struct Qdisc *sch, unsigned long cl,

			  struct sk_buff *skb, struct tcmsg *tcm)

{

	struct netem_sched_data *q = qdisc_priv(sch);



	if (cl != 1) 	/* only one class */

		return -ENOENT;



	tcm->tcm_handle |= TC_H_MIN(1);

	tcm->tcm_info = q->qdisc->handle;



	return 0;

}



static int netem_graft(struct Qdisc *sch, unsigned long arg, struct Qdisc *new,

		     struct Qdisc **old)

{

	struct netem_sched_data *q = qdisc_priv(sch);



	if (new == NULL)

		new = &noop_qdisc;



	sch_tree_lock(sch);

	*old = xchg(&q->qdisc, new);

	qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);

	qdisc_reset(*old);

	sch_tree_unlock(sch);



	return 0;

}



static struct Qdisc *netem_leaf(struct Qdisc *sch, unsigned long arg)

{

	struct netem_sched_data *q = qdisc_priv(sch);

	return q->qdisc;

}



static unsigned long netem_get(struct Qdisc *sch, u32 classid)

{

	return 1;

}



static void netem_put(struct Qdisc *sch, unsigned long arg)

{

}



static int netem_change_class(struct Qdisc *sch, u32 classid, u32 parentid,

			    struct nlattr **tca, unsigned long *arg)

{

	return -ENOSYS;

}



static int netem_delete(struct Qdisc *sch, unsigned long arg)

{

	return -ENOSYS;

}



static void netem_walk(struct Qdisc *sch, struct qdisc_walker *walker)

{

	if (!walker->stop) {

		if (walker->count >= walker->skip)

			if (walker->fn(sch, 1, walker) < 0) {

				walker->stop = 1;

				return;

			}

		walker->count++;

	}

}



static struct tcf_proto **netem_find_tcf(struct Qdisc *sch, unsigned long cl)

{

	return NULL;

}



static const struct Qdisc_class_ops netem_class_ops = {

	.graft		=	netem_graft,

	.leaf		=	netem_leaf,

	.get		=	netem_get,

	.put		=	netem_put,

	.change		=	netem_change_class,

	.delete		=	netem_delete,

	.walk		=	netem_walk,

	.tcf_chain	=	netem_find_tcf,

	.dump		=	netem_dump_class,

};



static struct Qdisc_ops netem_qdisc_ops __read_mostly = {

	.id		=	"netem",

	.cl_ops		=	&netem_class_ops,

	.priv_size	=	sizeof(struct netem_sched_data),

	.enqueue	=	netem_enqueue,

	.dequeue	=	netem_dequeue,

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