blob: fe91e50f9d98e7f2819242fc5a3b68ff905219a2 [file] [log] [blame]
David S. Miller6ec1c692009-09-06 01:58:51 -07001/*
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>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090012#include <linux/slab.h>
David S. Miller6ec1c692009-09-06 01:58:51 -070013#include <linux/kernel.h>
14#include <linux/string.h>
15#include <linux/errno.h>
16#include <linux/skbuff.h>
17#include <net/netlink.h>
18#include <net/pkt_sched.h>
19
20struct mq_sched {
21 struct Qdisc **qdiscs;
22};
23
24static void mq_destroy(struct Qdisc *sch)
25{
26 struct net_device *dev = qdisc_dev(sch);
27 struct mq_sched *priv = qdisc_priv(sch);
28 unsigned int ntx;
29
30 if (!priv->qdiscs)
31 return;
32 for (ntx = 0; ntx < dev->num_tx_queues && priv->qdiscs[ntx]; ntx++)
33 qdisc_destroy(priv->qdiscs[ntx]);
34 kfree(priv->qdiscs);
35}
36
37static int mq_init(struct Qdisc *sch, struct nlattr *opt)
38{
39 struct net_device *dev = qdisc_dev(sch);
40 struct mq_sched *priv = qdisc_priv(sch);
41 struct netdev_queue *dev_queue;
42 struct Qdisc *qdisc;
43 unsigned int ntx;
44
45 if (sch->parent != TC_H_ROOT)
46 return -EOPNOTSUPP;
47
48 if (!netif_is_multiqueue(dev))
49 return -EOPNOTSUPP;
50
51 /* pre-allocate qdiscs, attachment can't fail */
52 priv->qdiscs = kcalloc(dev->num_tx_queues, sizeof(priv->qdiscs[0]),
53 GFP_KERNEL);
54 if (priv->qdiscs == NULL)
55 return -ENOMEM;
56
57 for (ntx = 0; ntx < dev->num_tx_queues; ntx++) {
58 dev_queue = netdev_get_tx_queue(dev, ntx);
59 qdisc = qdisc_create_dflt(dev, dev_queue, &pfifo_fast_ops,
60 TC_H_MAKE(TC_H_MAJ(sch->handle),
61 TC_H_MIN(ntx + 1)));
62 if (qdisc == NULL)
63 goto err;
64 qdisc->flags |= TCQ_F_CAN_BYPASS;
65 priv->qdiscs[ntx] = qdisc;
66 }
67
Patrick McHardy23bcf632009-09-09 18:11:23 -070068 sch->flags |= TCQ_F_MQROOT;
David S. Miller6ec1c692009-09-06 01:58:51 -070069 return 0;
70
71err:
72 mq_destroy(sch);
73 return -ENOMEM;
74}
75
76static void mq_attach(struct Qdisc *sch)
77{
78 struct net_device *dev = qdisc_dev(sch);
79 struct mq_sched *priv = qdisc_priv(sch);
80 struct Qdisc *qdisc;
81 unsigned int ntx;
82
83 for (ntx = 0; ntx < dev->num_tx_queues; ntx++) {
84 qdisc = priv->qdiscs[ntx];
85 qdisc = dev_graft_qdisc(qdisc->dev_queue, qdisc);
86 if (qdisc)
87 qdisc_destroy(qdisc);
88 }
89 kfree(priv->qdiscs);
90 priv->qdiscs = NULL;
91}
92
93static int mq_dump(struct Qdisc *sch, struct sk_buff *skb)
94{
95 struct net_device *dev = qdisc_dev(sch);
96 struct Qdisc *qdisc;
97 unsigned int ntx;
98
99 sch->q.qlen = 0;
100 memset(&sch->bstats, 0, sizeof(sch->bstats));
101 memset(&sch->qstats, 0, sizeof(sch->qstats));
102
103 for (ntx = 0; ntx < dev->num_tx_queues; ntx++) {
104 qdisc = netdev_get_tx_queue(dev, ntx)->qdisc_sleeping;
105 spin_lock_bh(qdisc_lock(qdisc));
106 sch->q.qlen += qdisc->q.qlen;
107 sch->bstats.bytes += qdisc->bstats.bytes;
108 sch->bstats.packets += qdisc->bstats.packets;
109 sch->qstats.qlen += qdisc->qstats.qlen;
110 sch->qstats.backlog += qdisc->qstats.backlog;
111 sch->qstats.drops += qdisc->qstats.drops;
112 sch->qstats.requeues += qdisc->qstats.requeues;
113 sch->qstats.overlimits += qdisc->qstats.overlimits;
114 spin_unlock_bh(qdisc_lock(qdisc));
115 }
116 return 0;
117}
118
119static struct netdev_queue *mq_queue_get(struct Qdisc *sch, unsigned long cl)
120{
121 struct net_device *dev = qdisc_dev(sch);
122 unsigned long ntx = cl - 1;
123
124 if (ntx >= dev->num_tx_queues)
125 return NULL;
126 return netdev_get_tx_queue(dev, ntx);
127}
128
Jarek Poplawski926e61b2009-09-15 02:53:07 -0700129static struct netdev_queue *mq_select_queue(struct Qdisc *sch,
130 struct tcmsg *tcm)
David S. Miller6ec1c692009-09-06 01:58:51 -0700131{
132 unsigned int ntx = TC_H_MIN(tcm->tcm_parent);
Jarek Poplawski926e61b2009-09-15 02:53:07 -0700133 struct netdev_queue *dev_queue = mq_queue_get(sch, ntx);
David S. Miller6ec1c692009-09-06 01:58:51 -0700134
Jarek Poplawski926e61b2009-09-15 02:53:07 -0700135 if (!dev_queue) {
136 struct net_device *dev = qdisc_dev(sch);
137
138 return netdev_get_tx_queue(dev, 0);
139 }
140 return dev_queue;
David S. Miller6ec1c692009-09-06 01:58:51 -0700141}
142
143static int mq_graft(struct Qdisc *sch, unsigned long cl, struct Qdisc *new,
144 struct Qdisc **old)
145{
146 struct netdev_queue *dev_queue = mq_queue_get(sch, cl);
147 struct net_device *dev = qdisc_dev(sch);
148
149 if (dev->flags & IFF_UP)
150 dev_deactivate(dev);
151
152 *old = dev_graft_qdisc(dev_queue, new);
153
154 if (dev->flags & IFF_UP)
155 dev_activate(dev);
156 return 0;
157}
158
159static struct Qdisc *mq_leaf(struct Qdisc *sch, unsigned long cl)
160{
161 struct netdev_queue *dev_queue = mq_queue_get(sch, cl);
162
163 return dev_queue->qdisc_sleeping;
164}
165
166static unsigned long mq_get(struct Qdisc *sch, u32 classid)
167{
168 unsigned int ntx = TC_H_MIN(classid);
169
170 if (!mq_queue_get(sch, ntx))
171 return 0;
172 return ntx;
173}
174
175static void mq_put(struct Qdisc *sch, unsigned long cl)
176{
David S. Miller6ec1c692009-09-06 01:58:51 -0700177}
178
179static int mq_dump_class(struct Qdisc *sch, unsigned long cl,
180 struct sk_buff *skb, struct tcmsg *tcm)
181{
182 struct netdev_queue *dev_queue = mq_queue_get(sch, cl);
183
184 tcm->tcm_parent = TC_H_ROOT;
185 tcm->tcm_handle |= TC_H_MIN(cl);
186 tcm->tcm_info = dev_queue->qdisc_sleeping->handle;
187 return 0;
188}
189
190static int mq_dump_class_stats(struct Qdisc *sch, unsigned long cl,
191 struct gnet_dump *d)
192{
193 struct netdev_queue *dev_queue = mq_queue_get(sch, cl);
194
195 sch = dev_queue->qdisc_sleeping;
Jarek Poplawskia19d2152009-09-17 10:26:07 -0700196 sch->qstats.qlen = sch->q.qlen;
David S. Miller6ec1c692009-09-06 01:58:51 -0700197 if (gnet_stats_copy_basic(d, &sch->bstats) < 0 ||
198 gnet_stats_copy_queue(d, &sch->qstats) < 0)
199 return -1;
200 return 0;
201}
202
203static void mq_walk(struct Qdisc *sch, struct qdisc_walker *arg)
204{
205 struct net_device *dev = qdisc_dev(sch);
206 unsigned int ntx;
207
208 if (arg->stop)
209 return;
210
211 arg->count = arg->skip;
212 for (ntx = arg->skip; ntx < dev->num_tx_queues; ntx++) {
213 if (arg->fn(sch, ntx + 1, arg) < 0) {
214 arg->stop = 1;
215 break;
216 }
217 arg->count++;
218 }
219}
220
221static const struct Qdisc_class_ops mq_class_ops = {
222 .select_queue = mq_select_queue,
223 .graft = mq_graft,
224 .leaf = mq_leaf,
225 .get = mq_get,
226 .put = mq_put,
227 .walk = mq_walk,
228 .dump = mq_dump_class,
229 .dump_stats = mq_dump_class_stats,
230};
231
232struct Qdisc_ops mq_qdisc_ops __read_mostly = {
233 .cl_ops = &mq_class_ops,
234 .id = "mq",
235 .priv_size = sizeof(struct mq_sched),
236 .init = mq_init,
237 .destroy = mq_destroy,
238 .attach = mq_attach,
239 .dump = mq_dump,
240 .owner = THIS_MODULE,
241};