[mirror_ubuntu-bionic-kernel.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/slab.h>
#include <linux/kernel.h>
#include <linux/export.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)
		return -ENOMEM;

	for (ntx = 0; ntx < dev->num_tx_queues; ntx++) {
		dev_queue = netdev_get_tx_queue(dev, ntx);
		qdisc = qdisc_create_dflt(dev_queue, get_default_qdisc_ops(dev, ntx),
					  TC_H_MAKE(TC_H_MAJ(sch->handle),
						    TC_H_MIN(ntx + 1)));
		if (!qdisc)
			return -ENOMEM;
		priv->qdiscs[ntx] = qdisc;
		qdisc->flags |= TCQ_F_ONETXQUEUE | TCQ_F_NOPARENT;
	}

	sch->flags |= TCQ_F_MQROOT;
	return 0;
}

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

	for (ntx = 0; ntx < dev->num_tx_queues; ntx++) {
		qdisc = priv->qdiscs[ntx];
		old = dev_graft_qdisc(qdisc->dev_queue, qdisc);
		if (old)
			qdisc_destroy(old);
#ifdef CONFIG_NET_SCHED
		if (ntx < dev->real_num_tx_queues)
			qdisc_hash_add(qdisc, false);
#endif

	}
	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.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 struct netdev_queue *mq_select_queue(struct Qdisc *sch,
					    struct tcmsg *tcm)
{
	unsigned int ntx = TC_H_MIN(tcm->tcm_parent);
	struct netdev_queue *dev_queue = mq_queue_get(sch, ntx);

	if (!dev_queue) {
		struct net_device *dev = qdisc_dev(sch);

		return netdev_get_tx_queue(dev, 0);
	}
	return dev_queue;
}

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 (new)
		new->flags |= TCQ_F_ONETXQUEUE | TCQ_F_NOPARENT;
	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)
{
}

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(&sch->running, d, NULL, &sch->bstats) < 0 ||
	    gnet_stats_copy_queue(d, NULL, &sch->qstats, sch->q.qlen) < 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>
5a0e3ad6	12	#include <linux/slab.h>
6ec1c69a	13	#include <linux/kernel.h>
bc3b2d7f	14	#include <linux/export.h>
6ec1c69a DM	15	#include <linux/string.h>
	16	#include <linux/errno.h>
	17	#include <linux/skbuff.h>
	18	#include <net/netlink.h>
	19	#include <net/pkt_sched.h>
	20
	21	struct mq_sched {
	22	struct Qdisc **qdiscs;
	23	};
	24
	25	static void mq_destroy(struct Qdisc *sch)
	26	{
	27	struct net_device *dev = qdisc_dev(sch);
	28	struct mq_sched *priv = qdisc_priv(sch);
	29	unsigned int ntx;
	30
	31	if (!priv->qdiscs)
	32	return;
	33	for (ntx = 0; ntx < dev->num_tx_queues && priv->qdiscs[ntx]; ntx++)
	34	qdisc_destroy(priv->qdiscs[ntx]);
	35	kfree(priv->qdiscs);
	36	}
	37
	38	static int mq_init(struct Qdisc sch, struct nlattr opt)
	39	{
	40	struct net_device *dev = qdisc_dev(sch);
	41	struct mq_sched *priv = qdisc_priv(sch);
	42	struct netdev_queue *dev_queue;
	43	struct Qdisc *qdisc;
	44	unsigned int ntx;
	45
	46	if (sch->parent != TC_H_ROOT)
	47	return -EOPNOTSUPP;
	48
	49	if (!netif_is_multiqueue(dev))
	50	return -EOPNOTSUPP;
	51
	52	/* pre-allocate qdiscs, attachment can't fail */
	53	priv->qdiscs = kcalloc(dev->num_tx_queues, sizeof(priv->qdiscs[0]),
	54	GFP_KERNEL);
87b60cfa	55	if (!priv->qdiscs)
6ec1c69a DM	56	return -ENOMEM;
	57
	58	for (ntx = 0; ntx < dev->num_tx_queues; ntx++) {
	59	dev_queue = netdev_get_tx_queue(dev, ntx);
1f27cde3	60	qdisc = qdisc_create_dflt(dev_queue, get_default_qdisc_ops(dev, ntx),
6ec1c69a DM	61	TC_H_MAKE(TC_H_MAJ(sch->handle),
6ec1c69a DM	62	TC_H_MIN(ntx + 1)));
87b60cfa ED	63	if (!qdisc)
87b60cfa ED	64	return -ENOMEM;
6ec1c69a	65	priv->qdiscs[ntx] = qdisc;
4eaf3b84	66	qdisc->flags \|= TCQ_F_ONETXQUEUE \| TCQ_F_NOPARENT;
6ec1c69a DM	67	}
6ec1c69a DM	68
23bcf634	69	sch->flags \|= TCQ_F_MQROOT;
6ec1c69a	70	return 0;
6ec1c69a DM	71	}
	72
	73	static void mq_attach(struct Qdisc *sch)
	74	{
	75	struct net_device *dev = qdisc_dev(sch);
	76	struct mq_sched *priv = qdisc_priv(sch);
95dc1929	77	struct Qdisc qdisc, old;
6ec1c69a DM	78	unsigned int ntx;
	79
	80	for (ntx = 0; ntx < dev->num_tx_queues; ntx++) {
	81	qdisc = priv->qdiscs[ntx];
95dc1929 ED	82	old = dev_graft_qdisc(qdisc->dev_queue, qdisc);
	83	if (old)
	84	qdisc_destroy(old);
	85	#ifdef CONFIG_NET_SCHED
	86	if (ntx < dev->real_num_tx_queues)
49b49971	87	qdisc_hash_add(qdisc, false);
95dc1929 ED	88	#endif
95dc1929 ED	89
6ec1c69a DM	90	}
	91	kfree(priv->qdiscs);
	92	priv->qdiscs = NULL;
	93	}
	94
	95	static int mq_dump(struct Qdisc sch, struct sk_buff skb)
	96	{
	97	struct net_device *dev = qdisc_dev(sch);
	98	struct Qdisc *qdisc;
	99	unsigned int ntx;
	100
	101	sch->q.qlen = 0;
	102	memset(&sch->bstats, 0, sizeof(sch->bstats));
	103	memset(&sch->qstats, 0, sizeof(sch->qstats));
	104
	105	for (ntx = 0; ntx < dev->num_tx_queues; ntx++) {
	106	qdisc = netdev_get_tx_queue(dev, ntx)->qdisc_sleeping;
	107	spin_lock_bh(qdisc_lock(qdisc));
	108	sch->q.qlen += qdisc->q.qlen;
	109	sch->bstats.bytes += qdisc->bstats.bytes;
	110	sch->bstats.packets += qdisc->bstats.packets;
6ec1c69a DM	111	sch->qstats.backlog += qdisc->qstats.backlog;
	112	sch->qstats.drops += qdisc->qstats.drops;
	113	sch->qstats.requeues += qdisc->qstats.requeues;
	114	sch->qstats.overlimits += qdisc->qstats.overlimits;
	115	spin_unlock_bh(qdisc_lock(qdisc));
	116	}
	117	return 0;
	118	}
	119
	120	static struct netdev_queue mq_queue_get(struct Qdisc sch, unsigned long cl)
	121	{
	122	struct net_device *dev = qdisc_dev(sch);
	123	unsigned long ntx = cl - 1;
	124
	125	if (ntx >= dev->num_tx_queues)
	126	return NULL;
	127	return netdev_get_tx_queue(dev, ntx);
	128	}
	129
926e61b7 JP	130	static struct netdev_queue mq_select_queue(struct Qdisc sch,
926e61b7 JP	131	struct tcmsg *tcm)
6ec1c69a DM	132	{
6ec1c69a DM	133	unsigned int ntx = TC_H_MIN(tcm->tcm_parent);
926e61b7	134	struct netdev_queue *dev_queue = mq_queue_get(sch, ntx);
6ec1c69a	135
926e61b7 JP	136	if (!dev_queue) {
	137	struct net_device *dev = qdisc_dev(sch);
	138
	139	return netdev_get_tx_queue(dev, 0);
	140	}
	141	return dev_queue;
6ec1c69a DM	142	}
	143
	144	static int mq_graft(struct Qdisc sch, unsigned long cl, struct Qdisc new,
	145	struct Qdisc **old)
	146	{
	147	struct netdev_queue *dev_queue = mq_queue_get(sch, cl);
	148	struct net_device *dev = qdisc_dev(sch);
	149
	150	if (dev->flags & IFF_UP)
	151	dev_deactivate(dev);
	152
	153	*old = dev_graft_qdisc(dev_queue, new);
1abbe139	154	if (new)
4eaf3b84	155	new->flags \|= TCQ_F_ONETXQUEUE \| TCQ_F_NOPARENT;
6ec1c69a DM	156	if (dev->flags & IFF_UP)
	157	dev_activate(dev);
	158	return 0;
	159	}
	160
	161	static struct Qdisc mq_leaf(struct Qdisc sch, unsigned long cl)
	162	{
	163	struct netdev_queue *dev_queue = mq_queue_get(sch, cl);
	164
	165	return dev_queue->qdisc_sleeping;
	166	}
	167
	168	static unsigned long mq_get(struct Qdisc *sch, u32 classid)
	169	{
	170	unsigned int ntx = TC_H_MIN(classid);
	171
	172	if (!mq_queue_get(sch, ntx))
	173	return 0;
	174	return ntx;
	175	}
	176
	177	static void mq_put(struct Qdisc *sch, unsigned long cl)
	178	{
6ec1c69a DM	179	}
	180
	181	static int mq_dump_class(struct Qdisc *sch, unsigned long cl,
	182	struct sk_buff skb, struct tcmsg tcm)
	183	{
	184	struct netdev_queue *dev_queue = mq_queue_get(sch, cl);
	185
	186	tcm->tcm_parent = TC_H_ROOT;
	187	tcm->tcm_handle \|= TC_H_MIN(cl);
	188	tcm->tcm_info = dev_queue->qdisc_sleeping->handle;
	189	return 0;
	190	}
	191
	192	static int mq_dump_class_stats(struct Qdisc *sch, unsigned long cl,
	193	struct gnet_dump *d)
	194	{
	195	struct netdev_queue *dev_queue = mq_queue_get(sch, cl);
	196
	197	sch = dev_queue->qdisc_sleeping;
edb09eb1	198	if (gnet_stats_copy_basic(&sch->running, d, NULL, &sch->bstats) < 0 \|\|
b0ab6f92	199	gnet_stats_copy_queue(d, NULL, &sch->qstats, sch->q.qlen) < 0)
6ec1c69a DM	200	return -1;
	201	return 0;
	202	}
	203
	204	static void mq_walk(struct Qdisc sch, struct qdisc_walker arg)
	205	{
	206	struct net_device *dev = qdisc_dev(sch);
	207	unsigned int ntx;
	208
	209	if (arg->stop)
	210	return;
	211
	212	arg->count = arg->skip;
	213	for (ntx = arg->skip; ntx < dev->num_tx_queues; ntx++) {
	214	if (arg->fn(sch, ntx + 1, arg) < 0) {
	215	arg->stop = 1;
	216	break;
	217	}
	218	arg->count++;
	219	}
	220	}
	221
	222	static const struct Qdisc_class_ops mq_class_ops = {
	223	.select_queue = mq_select_queue,
	224	.graft = mq_graft,
	225	.leaf = mq_leaf,
	226	.get = mq_get,
	227	.put = mq_put,
	228	.walk = mq_walk,
	229	.dump = mq_dump_class,
	230	.dump_stats = mq_dump_class_stats,
	231	};
	232
	233	struct Qdisc_ops mq_qdisc_ops __read_mostly = {
	234	.cl_ops = &mq_class_ops,
	235	.id = "mq",
	236	.priv_size = sizeof(struct mq_sched),
	237	.init = mq_init,
	238	.destroy = mq_destroy,
	239	.attach = mq_attach,
	240	.dump = mq_dump,
	241	.owner = THIS_MODULE,
	242	};