[deliverable/linux.git] / net / sched / sch_mq.c

/*
 * net/sched/sch_mq.c		Classful multiqueue dummy scheduler
 *
 * Copyright (c) 2009 Patrick McHardy <kaber@trash.net>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * version 2 as published by the Free Software Foundation.
 */

#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/skbuff.h>
#include <net/netlink.h>
#include <net/pkt_sched.h>

struct mq_sched {
	struct Qdisc		**qdiscs;
};

static void mq_destroy(struct Qdisc *sch)
{
	struct net_device *dev = qdisc_dev(sch);
	struct mq_sched *priv = qdisc_priv(sch);
	unsigned int ntx;

	if (!priv->qdiscs)
		return;
	for (ntx = 0; ntx < dev->num_tx_queues && priv->qdiscs[ntx]; ntx++)
		qdisc_destroy(priv->qdiscs[ntx]);
	kfree(priv->qdiscs);
}

static int mq_init(struct Qdisc *sch, struct nlattr *opt)
{
	struct net_device *dev = qdisc_dev(sch);
	struct mq_sched *priv = qdisc_priv(sch);
	struct netdev_queue *dev_queue;
	struct Qdisc *qdisc;
	unsigned int ntx;

	if (sch->parent != TC_H_ROOT)
		return -EOPNOTSUPP;

	if (!netif_is_multiqueue(dev))
		return -EOPNOTSUPP;

	/* pre-allocate qdiscs, attachment can't fail */
	priv->qdiscs = kcalloc(dev->num_tx_queues, sizeof(priv->qdiscs[0]),
			       GFP_KERNEL);
	if (priv->qdiscs == NULL)
		return -ENOMEM;

	for (ntx = 0; ntx < dev->num_tx_queues; ntx++) {
		dev_queue = netdev_get_tx_queue(dev, ntx);
		qdisc = qdisc_create_dflt(dev, dev_queue, &pfifo_fast_ops,
					  TC_H_MAKE(TC_H_MAJ(sch->handle),
						    TC_H_MIN(ntx + 1)));
		if (qdisc == NULL)
			goto err;
		qdisc->flags |= TCQ_F_CAN_BYPASS;
		priv->qdiscs[ntx] = qdisc;
	}

	sch->flags |= TCQ_F_MQROOT;
	return 0;

err:
	mq_destroy(sch);
	return -ENOMEM;
}

static void mq_attach(struct Qdisc *sch)
{
	struct net_device *dev = qdisc_dev(sch);
	struct mq_sched *priv = qdisc_priv(sch);
	struct Qdisc *qdisc;
	unsigned int ntx;

	for (ntx = 0; ntx < dev->num_tx_queues; ntx++) {
		qdisc = priv->qdiscs[ntx];
		qdisc = dev_graft_qdisc(qdisc->dev_queue, qdisc);
		if (qdisc)
			qdisc_destroy(qdisc);
	}
	kfree(priv->qdiscs);
	priv->qdiscs = NULL;
}

static int mq_dump(struct Qdisc *sch, struct sk_buff *skb)
{
	struct net_device *dev = qdisc_dev(sch);
	struct Qdisc *qdisc;
	unsigned int ntx;

	sch->q.qlen = 0;
	memset(&sch->bstats, 0, sizeof(sch->bstats));
	memset(&sch->qstats, 0, sizeof(sch->qstats));

	for (ntx = 0; ntx < dev->num_tx_queues; ntx++) {
		qdisc = netdev_get_tx_queue(dev, ntx)->qdisc_sleeping;
		spin_lock_bh(qdisc_lock(qdisc));
		sch->q.qlen		+= qdisc->q.qlen;
		sch->bstats.bytes	+= qdisc->bstats.bytes;
		sch->bstats.packets	+= qdisc->bstats.packets;
		sch->qstats.qlen	+= qdisc->qstats.qlen;
		sch->qstats.backlog	+= qdisc->qstats.backlog;
		sch->qstats.drops	+= qdisc->qstats.drops;
		sch->qstats.requeues	+= qdisc->qstats.requeues;
		sch->qstats.overlimits	+= qdisc->qstats.overlimits;
		spin_unlock_bh(qdisc_lock(qdisc));
	}
	return 0;
}

static struct netdev_queue *mq_queue_get(struct Qdisc *sch, unsigned long cl)
{
	struct net_device *dev = qdisc_dev(sch);
	unsigned long ntx = cl - 1;

	if (ntx >= dev->num_tx_queues)
		return NULL;
	return netdev_get_tx_queue(dev, ntx);
}

static unsigned int mq_select_queue(struct Qdisc *sch, struct tcmsg *tcm)
{
	unsigned int ntx = TC_H_MIN(tcm->tcm_parent);

	if (!mq_queue_get(sch, ntx))
		return 0;
	return ntx - 1;
}

static int mq_graft(struct Qdisc *sch, unsigned long cl, struct Qdisc *new,
		    struct Qdisc **old)
{
	struct netdev_queue *dev_queue = mq_queue_get(sch, cl);
	struct net_device *dev = qdisc_dev(sch);

	if (dev->flags & IFF_UP)
		dev_deactivate(dev);

	*old = dev_graft_qdisc(dev_queue, new);

	if (dev->flags & IFF_UP)
		dev_activate(dev);
	return 0;
}

static struct Qdisc *mq_leaf(struct Qdisc *sch, unsigned long cl)
{
	struct netdev_queue *dev_queue = mq_queue_get(sch, cl);

	return dev_queue->qdisc_sleeping;
}

static unsigned long mq_get(struct Qdisc *sch, u32 classid)
{
	unsigned int ntx = TC_H_MIN(classid);

	if (!mq_queue_get(sch, ntx))
		return 0;
	return ntx;
}

static void mq_put(struct Qdisc *sch, unsigned long cl)
{
	return;
}

static int mq_dump_class(struct Qdisc *sch, unsigned long cl,
			 struct sk_buff *skb, struct tcmsg *tcm)
{
	struct netdev_queue *dev_queue = mq_queue_get(sch, cl);

	tcm->tcm_parent = TC_H_ROOT;
	tcm->tcm_handle |= TC_H_MIN(cl);
	tcm->tcm_info = dev_queue->qdisc_sleeping->handle;
	return 0;
}

static int mq_dump_class_stats(struct Qdisc *sch, unsigned long cl,
			       struct gnet_dump *d)
{
	struct netdev_queue *dev_queue = mq_queue_get(sch, cl);

	sch = dev_queue->qdisc_sleeping;
	if (gnet_stats_copy_basic(d, &sch->bstats) < 0 ||
	    gnet_stats_copy_queue(d, &sch->qstats) < 0)
		return -1;
	return 0;
}

static void mq_walk(struct Qdisc *sch, struct qdisc_walker *arg)
{
	struct net_device *dev = qdisc_dev(sch);
	unsigned int ntx;

	if (arg->stop)
		return;

	arg->count = arg->skip;
	for (ntx = arg->skip; ntx < dev->num_tx_queues; ntx++) {
		if (arg->fn(sch, ntx + 1, arg) < 0) {
			arg->stop = 1;
			break;
		}
		arg->count++;
	}
}

static const struct Qdisc_class_ops mq_class_ops = {
	.select_queue	= mq_select_queue,
	.graft		= mq_graft,
	.leaf		= mq_leaf,
	.get		= mq_get,
	.put		= mq_put,
	.walk		= mq_walk,
	.dump		= mq_dump_class,
	.dump_stats	= mq_dump_class_stats,
};

struct Qdisc_ops mq_qdisc_ops __read_mostly = {
	.cl_ops		= &mq_class_ops,
	.id		= "mq",
	.priv_size	= sizeof(struct mq_sched),
	.init		= mq_init,
	.destroy	= mq_destroy,
	.attach		= mq_attach,
	.dump		= mq_dump,
	.owner		= THIS_MODULE,
};
Commit	Line	Data
6ec1c69a DM	1	/*
	2	* net/sched/sch_mq.c Classful multiqueue dummy scheduler
	3	*
	4	* Copyright (c) 2009 Patrick McHardy <kaber@trash.net>
	5	*
	6	* This program is free software; you can redistribute it and/or
	7	* modify it under the terms of the GNU General Public License
	8	* version 2 as published by the Free Software Foundation.
	9	*/
	10
	11	#include <linux/types.h>
	12	#include <linux/kernel.h>
	13	#include <linux/string.h>
	14	#include <linux/errno.h>
	15	#include <linux/skbuff.h>
	16	#include <net/netlink.h>
	17	#include <net/pkt_sched.h>
	18
	19	struct mq_sched {
	20	struct Qdisc **qdiscs;
	21	};
	22
	23	static void mq_destroy(struct Qdisc *sch)
	24	{
	25	struct net_device *dev = qdisc_dev(sch);
	26	struct mq_sched *priv = qdisc_priv(sch);
	27	unsigned int ntx;
	28
	29	if (!priv->qdiscs)
	30	return;
	31	for (ntx = 0; ntx < dev->num_tx_queues && priv->qdiscs[ntx]; ntx++)
	32	qdisc_destroy(priv->qdiscs[ntx]);
	33	kfree(priv->qdiscs);
	34	}
	35
	36	static int mq_init(struct Qdisc sch, struct nlattr opt)
	37	{
	38	struct net_device *dev = qdisc_dev(sch);
	39	struct mq_sched *priv = qdisc_priv(sch);
	40	struct netdev_queue *dev_queue;
	41	struct Qdisc *qdisc;
	42	unsigned int ntx;
	43
	44	if (sch->parent != TC_H_ROOT)
	45	return -EOPNOTSUPP;
	46
	47	if (!netif_is_multiqueue(dev))
	48	return -EOPNOTSUPP;
	49
	50	/* pre-allocate qdiscs, attachment can't fail */
	51	priv->qdiscs = kcalloc(dev->num_tx_queues, sizeof(priv->qdiscs[0]),
	52	GFP_KERNEL);
	53	if (priv->qdiscs == NULL)
	54	return -ENOMEM;
	55
	56	for (ntx = 0; ntx < dev->num_tx_queues; ntx++) {
	57	dev_queue = netdev_get_tx_queue(dev, ntx);
	58	qdisc = qdisc_create_dflt(dev, dev_queue, &pfifo_fast_ops,
	59	TC_H_MAKE(TC_H_MAJ(sch->handle),
	60	TC_H_MIN(ntx + 1)));
	61	if (qdisc == NULL)
	62	goto err;
	63	qdisc->flags \|= TCQ_F_CAN_BYPASS;
	64	priv->qdiscs[ntx] = qdisc;
65	}
66
23bcf634	67	sch->flags \|= TCQ_F_MQROOT;
6ec1c69a DM	68	return 0;
	69
	70	err:
	71	mq_destroy(sch);
	72	return -ENOMEM;
	73	}
	74
	75	static void mq_attach(struct Qdisc *sch)
	76	{
	77	struct net_device *dev = qdisc_dev(sch);
	78	struct mq_sched *priv = qdisc_priv(sch);
	79	struct Qdisc *qdisc;
	80	unsigned int ntx;
	81
	82	for (ntx = 0; ntx < dev->num_tx_queues; ntx++) {
	83	qdisc = priv->qdiscs[ntx];
	84	qdisc = dev_graft_qdisc(qdisc->dev_queue, qdisc);
	85	if (qdisc)
	86	qdisc_destroy(qdisc);
	87	}
	88	kfree(priv->qdiscs);
	89	priv->qdiscs = NULL;
	90	}
	91
	92	static int mq_dump(struct Qdisc sch, struct sk_buff skb)
	93	{
	94	struct net_device *dev = qdisc_dev(sch);
	95	struct Qdisc *qdisc;
	96	unsigned int ntx;
	97
	98	sch->q.qlen = 0;
	99	memset(&sch->bstats, 0, sizeof(sch->bstats));
	100	memset(&sch->qstats, 0, sizeof(sch->qstats));
	101
	102	for (ntx = 0; ntx < dev->num_tx_queues; ntx++) {
	103	qdisc = netdev_get_tx_queue(dev, ntx)->qdisc_sleeping;
	104	spin_lock_bh(qdisc_lock(qdisc));
	105	sch->q.qlen += qdisc->q.qlen;
	106	sch->bstats.bytes += qdisc->bstats.bytes;
	107	sch->bstats.packets += qdisc->bstats.packets;
	108	sch->qstats.qlen += qdisc->qstats.qlen;
	109	sch->qstats.backlog += qdisc->qstats.backlog;
	110	sch->qstats.drops += qdisc->qstats.drops;
	111	sch->qstats.requeues += qdisc->qstats.requeues;
	112	sch->qstats.overlimits += qdisc->qstats.overlimits;
	113	spin_unlock_bh(qdisc_lock(qdisc));
	114	}
	115	return 0;
	116	}
	117
	118	static struct netdev_queue mq_queue_get(struct Qdisc sch, unsigned long cl)
	119	{
	120	struct net_device *dev = qdisc_dev(sch);
	121	unsigned long ntx = cl - 1;
	122
	123	if (ntx >= dev->num_tx_queues)
	124	return NULL;
	125	return netdev_get_tx_queue(dev, ntx);
	126	}
	127
	128	static unsigned int mq_select_queue(struct Qdisc sch, struct tcmsg tcm)
	129	{
	130	unsigned int ntx = TC_H_MIN(tcm->tcm_parent);
	131
132	if (!mq_queue_get(sch, ntx))
133	return 0;
134	return ntx - 1;
135	}
136
137	static int mq_graft(struct Qdisc sch, unsigned long cl, struct Qdisc new,
138	struct Qdisc **old)
139	{
140	struct netdev_queue *dev_queue = mq_queue_get(sch, cl);
141	struct net_device *dev = qdisc_dev(sch);
142
143	if (dev->flags & IFF_UP)
144	dev_deactivate(dev);
145
146	*old = dev_graft_qdisc(dev_queue, new);
147
148	if (dev->flags & IFF_UP)
149	dev_activate(dev);
150	return 0;
151	}
152
153	static struct Qdisc mq_leaf(struct Qdisc sch, unsigned long cl)
154	{
155	struct netdev_queue *dev_queue = mq_queue_get(sch, cl);
156
157	return dev_queue->qdisc_sleeping;
158	}
159
160	static unsigned long mq_get(struct Qdisc *sch, u32 classid)
161	{
162	unsigned int ntx = TC_H_MIN(classid);
163
164	if (!mq_queue_get(sch, ntx))
165	return 0;
166	return ntx;
167	}
168
169	static void mq_put(struct Qdisc *sch, unsigned long cl)
170	{
171	return;
172	}
173
174	static int mq_dump_class(struct Qdisc *sch, unsigned long cl,
175	struct sk_buff skb, struct tcmsg tcm)
176	{
177	struct netdev_queue *dev_queue = mq_queue_get(sch, cl);
178
179	tcm->tcm_parent = TC_H_ROOT;
180	tcm->tcm_handle \|= TC_H_MIN(cl);
181	tcm->tcm_info = dev_queue->qdisc_sleeping->handle;
182	return 0;
183	}
184
185	static int mq_dump_class_stats(struct Qdisc *sch, unsigned long cl,
186	struct gnet_dump *d)
187	{
188	struct netdev_queue *dev_queue = mq_queue_get(sch, cl);
189
190	sch = dev_queue->qdisc_sleeping;
191	if (gnet_stats_copy_basic(d, &sch->bstats) < 0 \|\|
192	gnet_stats_copy_queue(d, &sch->qstats) < 0)
193	return -1;
194	return 0;
195	}
196
197	static void mq_walk(struct Qdisc sch, struct qdisc_walker arg)
198	{
199	struct net_device *dev = qdisc_dev(sch);
200	unsigned int ntx;
201
202	if (arg->stop)
203	return;
204
205	arg->count = arg->skip;
206	for (ntx = arg->skip; ntx < dev->num_tx_queues; ntx++) {
207	if (arg->fn(sch, ntx + 1, arg) < 0) {
208	arg->stop = 1;
209	break;
210	}
211	arg->count++;
212	}
213	}
214
215	static const struct Qdisc_class_ops mq_class_ops = {
216	.select_queue = mq_select_queue,
217	.graft = mq_graft,
218	.leaf = mq_leaf,
219	.get = mq_get,
220	.put = mq_put,
221	.walk = mq_walk,
222	.dump = mq_dump_class,
223	.dump_stats = mq_dump_class_stats,
224	};
225
226	struct Qdisc_ops mq_qdisc_ops __read_mostly = {
227	.cl_ops = &mq_class_ops,
228	.id = "mq",
229	.priv_size = sizeof(struct mq_sched),
230	.init = mq_init,
231	.destroy = mq_destroy,
232	.attach = mq_attach,
233	.dump = mq_dump,
234	.owner = THIS_MODULE,
235	};