[linux-2.6-block.git] / net / sched / sch_codel.c

/*
 * Codel - The Controlled-Delay Active Queue Management algorithm
 *
 *  Copyright (C) 2011-2012 Kathleen Nichols <nichols@pollere.com>
 *  Copyright (C) 2011-2012 Van Jacobson <van@pollere.net>
 *
 *  Implemented on linux by :
 *  Copyright (C) 2012 Michael D. Taht <dave.taht@bufferbloat.net>
 *  Copyright (C) 2012,2015 Eric Dumazet <edumazet@google.com>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions, and the following disclaimer,
 *    without modification.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The names of the authors may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * Alternatively, provided that this notice is retained in full, this
 * software may be distributed under the terms of the GNU General
 * Public License ("GPL") version 2, in which case the provisions of the
 * GPL apply INSTEAD OF those given above.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
 * DAMAGE.
 *
 */

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/skbuff.h>
#include <linux/prefetch.h>
#include <net/pkt_sched.h>
#include <net/codel.h>
#include <net/codel_impl.h>
#include <net/codel_qdisc.h>


#define DEFAULT_CODEL_LIMIT 1000

struct codel_sched_data {
	struct codel_params	params;
	struct codel_vars	vars;
	struct codel_stats	stats;
	u32			drop_overlimit;
};

/* This is the specific function called from codel_dequeue()
 * to dequeue a packet from queue. Note: backlog is handled in
 * codel, we dont need to reduce it here.
 */
static struct sk_buff *dequeue_func(struct codel_vars *vars, void *ctx)
{
	struct Qdisc *sch = ctx;
	struct sk_buff *skb = __skb_dequeue(&sch->q);

	if (skb)
		sch->qstats.backlog -= qdisc_pkt_len(skb);

	prefetch(&skb->end); /* we'll need skb_shinfo() */
	return skb;
}

static void drop_func(struct sk_buff *skb, void *ctx)
{
	struct Qdisc *sch = ctx;

	qdisc_drop(skb, sch);
}

static struct sk_buff *codel_qdisc_dequeue(struct Qdisc *sch)
{
	struct codel_sched_data *q = qdisc_priv(sch);
	struct sk_buff *skb;

	skb = codel_dequeue(sch, &sch->qstats.backlog, &q->params, &q->vars,
			    &q->stats, qdisc_pkt_len, codel_get_enqueue_time,
			    drop_func, dequeue_func);

	/* We cant call qdisc_tree_reduce_backlog() if our qlen is 0,
	 * or HTB crashes. Defer it for next round.
	 */
	if (q->stats.drop_count && sch->q.qlen) {
		qdisc_tree_reduce_backlog(sch, q->stats.drop_count, q->stats.drop_len);
		q->stats.drop_count = 0;
		q->stats.drop_len = 0;
	}
	if (skb)
		qdisc_bstats_update(sch, skb);
	return skb;
}

static int codel_qdisc_enqueue(struct sk_buff *skb, struct Qdisc *sch)
{
	struct codel_sched_data *q;

	if (likely(qdisc_qlen(sch) < sch->limit)) {
		codel_set_enqueue_time(skb);
		return qdisc_enqueue_tail(skb, sch);
	}
	q = qdisc_priv(sch);
	q->drop_overlimit++;
	return qdisc_drop(skb, sch);
}

static const struct nla_policy codel_policy[TCA_CODEL_MAX + 1] = {
	[TCA_CODEL_TARGET]	= { .type = NLA_U32 },
	[TCA_CODEL_LIMIT]	= { .type = NLA_U32 },
	[TCA_CODEL_INTERVAL]	= { .type = NLA_U32 },
	[TCA_CODEL_ECN]		= { .type = NLA_U32 },
	[TCA_CODEL_CE_THRESHOLD]= { .type = NLA_U32 },
};

static int codel_change(struct Qdisc *sch, struct nlattr *opt)
{
	struct codel_sched_data *q = qdisc_priv(sch);
	struct nlattr *tb[TCA_CODEL_MAX + 1];
	unsigned int qlen, dropped = 0;
	int err;

	if (!opt)
		return -EINVAL;

	err = nla_parse_nested(tb, TCA_CODEL_MAX, opt, codel_policy);
	if (err < 0)
		return err;

	sch_tree_lock(sch);

	if (tb[TCA_CODEL_TARGET]) {
		u32 target = nla_get_u32(tb[TCA_CODEL_TARGET]);

		q->params.target = ((u64)target * NSEC_PER_USEC) >> CODEL_SHIFT;
	}

	if (tb[TCA_CODEL_CE_THRESHOLD]) {
		u64 val = nla_get_u32(tb[TCA_CODEL_CE_THRESHOLD]);

		q->params.ce_threshold = (val * NSEC_PER_USEC) >> CODEL_SHIFT;
	}

	if (tb[TCA_CODEL_INTERVAL]) {
		u32 interval = nla_get_u32(tb[TCA_CODEL_INTERVAL]);

		q->params.interval = ((u64)interval * NSEC_PER_USEC) >> CODEL_SHIFT;
	}

	if (tb[TCA_CODEL_LIMIT])
		sch->limit = nla_get_u32(tb[TCA_CODEL_LIMIT]);

	if (tb[TCA_CODEL_ECN])
		q->params.ecn = !!nla_get_u32(tb[TCA_CODEL_ECN]);

	qlen = sch->q.qlen;
	while (sch->q.qlen > sch->limit) {
		struct sk_buff *skb = __skb_dequeue(&sch->q);

		dropped += qdisc_pkt_len(skb);
		qdisc_qstats_backlog_dec(sch, skb);
		qdisc_drop(skb, sch);
	}
	qdisc_tree_reduce_backlog(sch, qlen - sch->q.qlen, dropped);

	sch_tree_unlock(sch);
	return 0;
}

static int codel_init(struct Qdisc *sch, struct nlattr *opt)
{
	struct codel_sched_data *q = qdisc_priv(sch);

	sch->limit = DEFAULT_CODEL_LIMIT;

	codel_params_init(&q->params);
	codel_vars_init(&q->vars);
	codel_stats_init(&q->stats);
	q->params.mtu = psched_mtu(qdisc_dev(sch));

	if (opt) {
		int err = codel_change(sch, opt);

		if (err)
			return err;
	}

	if (sch->limit >= 1)
		sch->flags |= TCQ_F_CAN_BYPASS;
	else
		sch->flags &= ~TCQ_F_CAN_BYPASS;

	return 0;
}

static int codel_dump(struct Qdisc *sch, struct sk_buff *skb)
{
	struct codel_sched_data *q = qdisc_priv(sch);
	struct nlattr *opts;

	opts = nla_nest_start(skb, TCA_OPTIONS);
	if (opts == NULL)
		goto nla_put_failure;

	if (nla_put_u32(skb, TCA_CODEL_TARGET,
			codel_time_to_us(q->params.target)) ||
	    nla_put_u32(skb, TCA_CODEL_LIMIT,
			sch->limit) ||
	    nla_put_u32(skb, TCA_CODEL_INTERVAL,
			codel_time_to_us(q->params.interval)) ||
	    nla_put_u32(skb, TCA_CODEL_ECN,
			q->params.ecn))
		goto nla_put_failure;
	if (q->params.ce_threshold != CODEL_DISABLED_THRESHOLD &&
	    nla_put_u32(skb, TCA_CODEL_CE_THRESHOLD,
			codel_time_to_us(q->params.ce_threshold)))
		goto nla_put_failure;
	return nla_nest_end(skb, opts);

nla_put_failure:
	nla_nest_cancel(skb, opts);
	return -1;
}

static int codel_dump_stats(struct Qdisc *sch, struct gnet_dump *d)
{
	const struct codel_sched_data *q = qdisc_priv(sch);
	struct tc_codel_xstats st = {
		.maxpacket	= q->stats.maxpacket,
		.count		= q->vars.count,
		.lastcount	= q->vars.lastcount,
		.drop_overlimit = q->drop_overlimit,
		.ldelay		= codel_time_to_us(q->vars.ldelay),
		.dropping	= q->vars.dropping,
		.ecn_mark	= q->stats.ecn_mark,
		.ce_mark	= q->stats.ce_mark,
	};

	if (q->vars.dropping) {
		codel_tdiff_t delta = q->vars.drop_next - codel_get_time();

		if (delta >= 0)
			st.drop_next = codel_time_to_us(delta);
		else
			st.drop_next = -codel_time_to_us(-delta);
	}

	return gnet_stats_copy_app(d, &st, sizeof(st));
}

static void codel_reset(struct Qdisc *sch)
{
	struct codel_sched_data *q = qdisc_priv(sch);

	qdisc_reset_queue(sch);
	codel_vars_init(&q->vars);
}

static struct Qdisc_ops codel_qdisc_ops __read_mostly = {
	.id		=	"codel",
	.priv_size	=	sizeof(struct codel_sched_data),

	.enqueue	=	codel_qdisc_enqueue,
	.dequeue	=	codel_qdisc_dequeue,
	.peek		=	qdisc_peek_dequeued,
	.init		=	codel_init,
	.reset		=	codel_reset,
	.change 	=	codel_change,
	.dump		=	codel_dump,
	.dump_stats	=	codel_dump_stats,
	.owner		=	THIS_MODULE,
};

static int __init codel_module_init(void)
{
	return register_qdisc(&codel_qdisc_ops);
}

static void __exit codel_module_exit(void)
{
	unregister_qdisc(&codel_qdisc_ops);
}

module_init(codel_module_init)
module_exit(codel_module_exit)

MODULE_DESCRIPTION("Controlled Delay queue discipline");
MODULE_AUTHOR("Dave Taht");
MODULE_AUTHOR("Eric Dumazet");
MODULE_LICENSE("Dual BSD/GPL");
Commit	Line	Data
76e3cc12 ED	1	/*
	2	* Codel - The Controlled-Delay Active Queue Management algorithm
	3	*
	4	* Copyright (C) 2011-2012 Kathleen Nichols <nichols@pollere.com>
	5	* Copyright (C) 2011-2012 Van Jacobson <van@pollere.net>
	6	*
	7	* Implemented on linux by :
	8	* Copyright (C) 2012 Michael D. Taht <dave.taht@bufferbloat.net>
80ba92fa	9	* Copyright (C) 2012,2015 Eric Dumazet <edumazet@google.com>
76e3cc12 ED	10	*
	11	* Redistribution and use in source and binary forms, with or without
	12	* modification, are permitted provided that the following conditions
	13	* are met:
	14	* 1. Redistributions of source code must retain the above copyright
	15	* notice, this list of conditions, and the following disclaimer,
	16	* without modification.
	17	* 2. Redistributions in binary form must reproduce the above copyright
	18	* notice, this list of conditions and the following disclaimer in the
	19	* documentation and/or other materials provided with the distribution.
	20	* 3. The names of the authors may not be used to endorse or promote products
	21	* derived from this software without specific prior written permission.
	22	*
	23	* Alternatively, provided that this notice is retained in full, this
	24	* software may be distributed under the terms of the GNU General
	25	* Public License ("GPL") version 2, in which case the provisions of the
	26	* GPL apply INSTEAD OF those given above.
	27	*
	28	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	29	* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	30	* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
	31	* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
	32	* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	33	* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
	34	* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	35	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	36	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	37	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	38	* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
	39	* DAMAGE.
	40	*
	41	*/
	42
	43	#include <linux/module.h>
	44	#include <linux/slab.h>
	45	#include <linux/types.h>
	46	#include <linux/kernel.h>
	47	#include <linux/errno.h>
	48	#include <linux/skbuff.h>
ce5b4b97	49	#include <linux/prefetch.h>
76e3cc12 ED	50	#include <net/pkt_sched.h>
76e3cc12 ED	51	#include <net/codel.h>
d068ca2a MK	52	#include <net/codel_impl.h>
d068ca2a MK	53	#include <net/codel_qdisc.h>
76e3cc12 ED	54
	55
	56	#define DEFAULT_CODEL_LIMIT 1000
	57
	58	struct codel_sched_data {
	59	struct codel_params params;
	60	struct codel_vars vars;
	61	struct codel_stats stats;
	62	u32 drop_overlimit;
	63	};
	64
	65	/* This is the specific function called from codel_dequeue()
	66	* to dequeue a packet from queue. Note: backlog is handled in
	67	* codel, we dont need to reduce it here.
	68	*/
79bdc4c8	69	static struct sk_buff dequeue_func(struct codel_vars vars, void *ctx)
76e3cc12	70	{
79bdc4c8	71	struct Qdisc *sch = ctx;
76e3cc12 ED	72	struct sk_buff *skb = __skb_dequeue(&sch->q);
76e3cc12 ED	73
79bdc4c8 MK	74	if (skb)
	75	sch->qstats.backlog -= qdisc_pkt_len(skb);
	76
76e3cc12 ED	77	prefetch(&skb->end); /* we'll need skb_shinfo() */
	78	return skb;
	79	}
	80
79bdc4c8 MK	81	static void drop_func(struct sk_buff skb, void ctx)
	82	{
	83	struct Qdisc *sch = ctx;
	84
	85	qdisc_drop(skb, sch);
	86	}
	87
76e3cc12 ED	88	static struct sk_buff codel_qdisc_dequeue(struct Qdisc sch)
	89	{
	90	struct codel_sched_data *q = qdisc_priv(sch);
	91	struct sk_buff *skb;
	92
79bdc4c8 MK	93	skb = codel_dequeue(sch, &sch->qstats.backlog, &q->params, &q->vars,
	94	&q->stats, qdisc_pkt_len, codel_get_enqueue_time,
	95	drop_func, dequeue_func);
865ec552	96
2ccccf5f	97	/* We cant call qdisc_tree_reduce_backlog() if our qlen is 0,
76e3cc12 ED	98	* or HTB crashes. Defer it for next round.
	99	*/
	100	if (q->stats.drop_count && sch->q.qlen) {
2ccccf5f	101	qdisc_tree_reduce_backlog(sch, q->stats.drop_count, q->stats.drop_len);
76e3cc12	102	q->stats.drop_count = 0;
2ccccf5f	103	q->stats.drop_len = 0;
76e3cc12 ED	104	}
	105	if (skb)
	106	qdisc_bstats_update(sch, skb);
	107	return skb;
	108	}
	109
	110	static int codel_qdisc_enqueue(struct sk_buff skb, struct Qdisc sch)
	111	{
	112	struct codel_sched_data *q;
	113
	114	if (likely(qdisc_qlen(sch) < sch->limit)) {
	115	codel_set_enqueue_time(skb);
	116	return qdisc_enqueue_tail(skb, sch);
	117	}
	118	q = qdisc_priv(sch);
	119	q->drop_overlimit++;
	120	return qdisc_drop(skb, sch);
	121	}
	122
	123	static const struct nla_policy codel_policy[TCA_CODEL_MAX + 1] = {
	124	[TCA_CODEL_TARGET] = { .type = NLA_U32 },
	125	[TCA_CODEL_LIMIT] = { .type = NLA_U32 },
	126	[TCA_CODEL_INTERVAL] = { .type = NLA_U32 },
	127	[TCA_CODEL_ECN] = { .type = NLA_U32 },
80ba92fa	128	[TCA_CODEL_CE_THRESHOLD]= { .type = NLA_U32 },
76e3cc12 ED	129	};
	130
	131	static int codel_change(struct Qdisc sch, struct nlattr opt)
	132	{
	133	struct codel_sched_data *q = qdisc_priv(sch);
	134	struct nlattr *tb[TCA_CODEL_MAX + 1];
2ccccf5f	135	unsigned int qlen, dropped = 0;
76e3cc12 ED	136	int err;
	137
	138	if (!opt)
	139	return -EINVAL;
	140
	141	err = nla_parse_nested(tb, TCA_CODEL_MAX, opt, codel_policy);
	142	if (err < 0)
	143	return err;
	144
	145	sch_tree_lock(sch);
	146
	147	if (tb[TCA_CODEL_TARGET]) {
	148	u32 target = nla_get_u32(tb[TCA_CODEL_TARGET]);
	149
	150	q->params.target = ((u64)target * NSEC_PER_USEC) >> CODEL_SHIFT;
	151	}
	152
80ba92fa ED	153	if (tb[TCA_CODEL_CE_THRESHOLD]) {
	154	u64 val = nla_get_u32(tb[TCA_CODEL_CE_THRESHOLD]);
	155
	156	q->params.ce_threshold = (val * NSEC_PER_USEC) >> CODEL_SHIFT;
	157	}
	158
76e3cc12 ED	159	if (tb[TCA_CODEL_INTERVAL]) {
	160	u32 interval = nla_get_u32(tb[TCA_CODEL_INTERVAL]);
	161
	162	q->params.interval = ((u64)interval * NSEC_PER_USEC) >> CODEL_SHIFT;
	163	}
	164
	165	if (tb[TCA_CODEL_LIMIT])
	166	sch->limit = nla_get_u32(tb[TCA_CODEL_LIMIT]);
	167
	168	if (tb[TCA_CODEL_ECN])
	169	q->params.ecn = !!nla_get_u32(tb[TCA_CODEL_ECN]);
	170
	171	qlen = sch->q.qlen;
	172	while (sch->q.qlen > sch->limit) {
	173	struct sk_buff *skb = __skb_dequeue(&sch->q);
	174
2ccccf5f	175	dropped += qdisc_pkt_len(skb);
25331d6c	176	qdisc_qstats_backlog_dec(sch, skb);
76e3cc12 ED	177	qdisc_drop(skb, sch);
76e3cc12 ED	178	}
2ccccf5f	179	qdisc_tree_reduce_backlog(sch, qlen - sch->q.qlen, dropped);
76e3cc12 ED	180
	181	sch_tree_unlock(sch);
	182	return 0;
	183	}
	184
	185	static int codel_init(struct Qdisc sch, struct nlattr opt)
	186	{
	187	struct codel_sched_data *q = qdisc_priv(sch);
	188
	189	sch->limit = DEFAULT_CODEL_LIMIT;
	190
79bdc4c8	191	codel_params_init(&q->params);
76e3cc12 ED	192	codel_vars_init(&q->vars);
76e3cc12 ED	193	codel_stats_init(&q->stats);
79bdc4c8	194	q->params.mtu = psched_mtu(qdisc_dev(sch));
76e3cc12 ED	195
	196	if (opt) {
	197	int err = codel_change(sch, opt);
	198
	199	if (err)
	200	return err;
	201	}
	202
	203	if (sch->limit >= 1)
	204	sch->flags \|= TCQ_F_CAN_BYPASS;
	205	else
	206	sch->flags &= ~TCQ_F_CAN_BYPASS;
	207
	208	return 0;
	209	}
	210
	211	static int codel_dump(struct Qdisc sch, struct sk_buff skb)
	212	{
	213	struct codel_sched_data *q = qdisc_priv(sch);
	214	struct nlattr *opts;
	215
	216	opts = nla_nest_start(skb, TCA_OPTIONS);
	217	if (opts == NULL)
	218	goto nla_put_failure;
	219
	220	if (nla_put_u32(skb, TCA_CODEL_TARGET,
	221	codel_time_to_us(q->params.target)) \|\|
	222	nla_put_u32(skb, TCA_CODEL_LIMIT,
	223	sch->limit) \|\|
	224	nla_put_u32(skb, TCA_CODEL_INTERVAL,
	225	codel_time_to_us(q->params.interval)) \|\|
	226	nla_put_u32(skb, TCA_CODEL_ECN,
	227	q->params.ecn))
	228	goto nla_put_failure;
80ba92fa ED	229	if (q->params.ce_threshold != CODEL_DISABLED_THRESHOLD &&
	230	nla_put_u32(skb, TCA_CODEL_CE_THRESHOLD,
	231	codel_time_to_us(q->params.ce_threshold)))
	232	goto nla_put_failure;
76e3cc12 ED	233	return nla_nest_end(skb, opts);
	234
	235	nla_put_failure:
	236	nla_nest_cancel(skb, opts);
	237	return -1;
	238	}
	239
	240	static int codel_dump_stats(struct Qdisc sch, struct gnet_dump d)
	241	{
	242	const struct codel_sched_data *q = qdisc_priv(sch);
	243	struct tc_codel_xstats st = {
	244	.maxpacket = q->stats.maxpacket,
	245	.count = q->vars.count,
	246	.lastcount = q->vars.lastcount,
	247	.drop_overlimit = q->drop_overlimit,
	248	.ldelay = codel_time_to_us(q->vars.ldelay),
	249	.dropping = q->vars.dropping,
	250	.ecn_mark = q->stats.ecn_mark,
80ba92fa	251	.ce_mark = q->stats.ce_mark,
76e3cc12 ED	252	};
	253
	254	if (q->vars.dropping) {
	255	codel_tdiff_t delta = q->vars.drop_next - codel_get_time();
	256
	257	if (delta >= 0)
	258	st.drop_next = codel_time_to_us(delta);
	259	else
	260	st.drop_next = -codel_time_to_us(-delta);
	261	}
	262
	263	return gnet_stats_copy_app(d, &st, sizeof(st));
	264	}
	265
	266	static void codel_reset(struct Qdisc *sch)
	267	{
	268	struct codel_sched_data *q = qdisc_priv(sch);
	269
	270	qdisc_reset_queue(sch);
	271	codel_vars_init(&q->vars);
	272	}
	273
	274	static struct Qdisc_ops codel_qdisc_ops __read_mostly = {
	275	.id = "codel",
	276	.priv_size = sizeof(struct codel_sched_data),
	277
	278	.enqueue = codel_qdisc_enqueue,
	279	.dequeue = codel_qdisc_dequeue,
	280	.peek = qdisc_peek_dequeued,
	281	.init = codel_init,
	282	.reset = codel_reset,
	283	.change = codel_change,
	284	.dump = codel_dump,
	285	.dump_stats = codel_dump_stats,
	286	.owner = THIS_MODULE,
	287	};
	288
	289	static int __init codel_module_init(void)
	290	{
	291	return register_qdisc(&codel_qdisc_ops);
	292	}
	293
	294	static void __exit codel_module_exit(void)
	295	{
	296	unregister_qdisc(&codel_qdisc_ops);
	297	}
	298
	299	module_init(codel_module_init)
	300	module_exit(codel_module_exit)
	301
	302	MODULE_DESCRIPTION("Controlled Delay queue discipline");
	303	MODULE_AUTHOR("Dave Taht");
	304	MODULE_AUTHOR("Eric Dumazet");
	305	MODULE_LICENSE("Dual BSD/GPL");