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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/slab.h>
13#include <linux/kernel.h>
14#include <linux/export.h>
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#include <net/sch_generic.h>
21
22struct mq_sched {
23 struct Qdisc **qdiscs;
24};
25
26static void mq_destroy(struct Qdisc *sch)
27{
28 struct net_device *dev = qdisc_dev(sch);
29 struct mq_sched *priv = qdisc_priv(sch);
30 unsigned int ntx;
31
32 if (!priv->qdiscs)
33 return;
34 for (ntx = 0; ntx < dev->num_tx_queues && priv->qdiscs[ntx]; ntx++)
35 qdisc_destroy(priv->qdiscs[ntx]);
36 kfree(priv->qdiscs);
37}
38
39static int mq_init(struct Qdisc *sch, struct nlattr *opt,
40 struct netlink_ext_ack *extack)
41{
42 struct net_device *dev = qdisc_dev(sch);
43 struct mq_sched *priv = qdisc_priv(sch);
44 struct netdev_queue *dev_queue;
45 struct Qdisc *qdisc;
46 unsigned int ntx;
47
48 if (sch->parent != TC_H_ROOT)
49 return -EOPNOTSUPP;
50
51 if (!netif_is_multiqueue(dev))
52 return -EOPNOTSUPP;
53
54 /* pre-allocate qdiscs, attachment can't fail */
55 priv->qdiscs = kcalloc(dev->num_tx_queues, sizeof(priv->qdiscs[0]),
56 GFP_KERNEL);
57 if (!priv->qdiscs)
58 return -ENOMEM;
59
60 for (ntx = 0; ntx < dev->num_tx_queues; ntx++) {
61 dev_queue = netdev_get_tx_queue(dev, ntx);
62 qdisc = qdisc_create_dflt(dev_queue, get_default_qdisc_ops(dev, ntx),
63 TC_H_MAKE(TC_H_MAJ(sch->handle),
64 TC_H_MIN(ntx + 1)),
65 extack);
66 if (!qdisc)
67 return -ENOMEM;
68 priv->qdiscs[ntx] = qdisc;
69 qdisc->flags |= TCQ_F_ONETXQUEUE | TCQ_F_NOPARENT;
70 }
71
72 sch->flags |= TCQ_F_MQROOT;
73 return 0;
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, *old;
81 unsigned int ntx;
82
83 for (ntx = 0; ntx < dev->num_tx_queues; ntx++) {
84 qdisc = priv->qdiscs[ntx];
85 old = dev_graft_qdisc(qdisc->dev_queue, qdisc);
86 if (old)
87 qdisc_destroy(old);
88#ifdef CONFIG_NET_SCHED
89 if (ntx < dev->real_num_tx_queues)
90 qdisc_hash_add(qdisc, false);
91#endif
92
93 }
94 kfree(priv->qdiscs);
95 priv->qdiscs = NULL;
96}
97
98static int mq_dump(struct Qdisc *sch, struct sk_buff *skb)
99{
100 struct net_device *dev = qdisc_dev(sch);
101 struct Qdisc *qdisc;
102 unsigned int ntx;
103 __u32 qlen = 0;
104
105 sch->q.qlen = 0;
106 memset(&sch->bstats, 0, sizeof(sch->bstats));
107 memset(&sch->qstats, 0, sizeof(sch->qstats));
108
109 /* MQ supports lockless qdiscs. However, statistics accounting needs
110 * to account for all, none, or a mix of locked and unlocked child
111 * qdiscs. Percpu stats are added to counters in-band and locking
112 * qdisc totals are added at end.
113 */
114 for (ntx = 0; ntx < dev->num_tx_queues; ntx++) {
115 qdisc = netdev_get_tx_queue(dev, ntx)->qdisc_sleeping;
116 spin_lock_bh(qdisc_lock(qdisc));
117
118 if (qdisc_is_percpu_stats(qdisc)) {
119 qlen = qdisc_qlen_sum(qdisc);
120 __gnet_stats_copy_basic(NULL, &sch->bstats,
121 qdisc->cpu_bstats,
122 &qdisc->bstats);
123 __gnet_stats_copy_queue(&sch->qstats,
124 qdisc->cpu_qstats,
125 &qdisc->qstats, qlen);
126 } else {
127 sch->q.qlen += qdisc->q.qlen;
128 sch->bstats.bytes += qdisc->bstats.bytes;
129 sch->bstats.packets += qdisc->bstats.packets;
130 sch->qstats.backlog += qdisc->qstats.backlog;
131 sch->qstats.drops += qdisc->qstats.drops;
132 sch->qstats.requeues += qdisc->qstats.requeues;
133 sch->qstats.overlimits += qdisc->qstats.overlimits;
134 }
135
136 spin_unlock_bh(qdisc_lock(qdisc));
137 }
138
139 return 0;
140}
141
142static struct netdev_queue *mq_queue_get(struct Qdisc *sch, unsigned long cl)
143{
144 struct net_device *dev = qdisc_dev(sch);
145 unsigned long ntx = cl - 1;
146
147 if (ntx >= dev->num_tx_queues)
148 return NULL;
149 return netdev_get_tx_queue(dev, ntx);
150}
151
152static struct netdev_queue *mq_select_queue(struct Qdisc *sch,
153 struct tcmsg *tcm)
154{
155 return mq_queue_get(sch, TC_H_MIN(tcm->tcm_parent));
156}
157
158static int mq_graft(struct Qdisc *sch, unsigned long cl, struct Qdisc *new,
159 struct Qdisc **old, struct netlink_ext_ack *extack)
160{
161 struct netdev_queue *dev_queue = mq_queue_get(sch, cl);
162 struct net_device *dev = qdisc_dev(sch);
163
164 if (dev->flags & IFF_UP)
165 dev_deactivate(dev);
166
167 *old = dev_graft_qdisc(dev_queue, new);
168 if (new)
169 new->flags |= TCQ_F_ONETXQUEUE | TCQ_F_NOPARENT;
170 if (dev->flags & IFF_UP)
171 dev_activate(dev);
172 return 0;
173}
174
175static struct Qdisc *mq_leaf(struct Qdisc *sch, unsigned long cl)
176{
177 struct netdev_queue *dev_queue = mq_queue_get(sch, cl);
178
179 return dev_queue->qdisc_sleeping;
180}
181
182static unsigned long mq_find(struct Qdisc *sch, u32 classid)
183{
184 unsigned int ntx = TC_H_MIN(classid);
185
186 if (!mq_queue_get(sch, ntx))
187 return 0;
188 return ntx;
189}
190
191static int mq_dump_class(struct Qdisc *sch, unsigned long cl,
192 struct sk_buff *skb, struct tcmsg *tcm)
193{
194 struct netdev_queue *dev_queue = mq_queue_get(sch, cl);
195
196 tcm->tcm_parent = TC_H_ROOT;
197 tcm->tcm_handle |= TC_H_MIN(cl);
198 tcm->tcm_info = dev_queue->qdisc_sleeping->handle;
199 return 0;
200}
201
202static int mq_dump_class_stats(struct Qdisc *sch, unsigned long cl,
203 struct gnet_dump *d)
204{
205 struct netdev_queue *dev_queue = mq_queue_get(sch, cl);
206
207 sch = dev_queue->qdisc_sleeping;
208 if (gnet_stats_copy_basic(&sch->running, d, NULL, &sch->bstats) < 0 ||
209 gnet_stats_copy_queue(d, NULL, &sch->qstats, sch->q.qlen) < 0)
210 return -1;
211 return 0;
212}
213
214static void mq_walk(struct Qdisc *sch, struct qdisc_walker *arg)
215{
216 struct net_device *dev = qdisc_dev(sch);
217 unsigned int ntx;
218
219 if (arg->stop)
220 return;
221
222 arg->count = arg->skip;
223 for (ntx = arg->skip; ntx < dev->num_tx_queues; ntx++) {
224 if (arg->fn(sch, ntx + 1, arg) < 0) {
225 arg->stop = 1;
226 break;
227 }
228 arg->count++;
229 }
230}
231
232static const struct Qdisc_class_ops mq_class_ops = {
233 .select_queue = mq_select_queue,
234 .graft = mq_graft,
235 .leaf = mq_leaf,
236 .find = mq_find,
237 .walk = mq_walk,
238 .dump = mq_dump_class,
239 .dump_stats = mq_dump_class_stats,
240};
241
242struct Qdisc_ops mq_qdisc_ops __read_mostly = {
243 .cl_ops = &mq_class_ops,
244 .id = "mq",
245 .priv_size = sizeof(struct mq_sched),
246 .init = mq_init,
247 .destroy = mq_destroy,
248 .attach = mq_attach,
249 .dump = mq_dump,
250 .owner = THIS_MODULE,
251};
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/slab.h>
13#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_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 priv->qdiscs[ntx] = qdisc;
65 }
66
67 sch->flags |= TCQ_F_MQROOT;
68 return 0;
69
70err:
71 mq_destroy(sch);
72 return -ENOMEM;
73}
74
75static 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
92static 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
118static 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
128static struct netdev_queue *mq_select_queue(struct Qdisc *sch,
129 struct tcmsg *tcm)
130{
131 unsigned int ntx = TC_H_MIN(tcm->tcm_parent);
132 struct netdev_queue *dev_queue = mq_queue_get(sch, ntx);
133
134 if (!dev_queue) {
135 struct net_device *dev = qdisc_dev(sch);
136
137 return netdev_get_tx_queue(dev, 0);
138 }
139 return dev_queue;
140}
141
142static int mq_graft(struct Qdisc *sch, unsigned long cl, struct Qdisc *new,
143 struct Qdisc **old)
144{
145 struct netdev_queue *dev_queue = mq_queue_get(sch, cl);
146 struct net_device *dev = qdisc_dev(sch);
147
148 if (dev->flags & IFF_UP)
149 dev_deactivate(dev);
150
151 *old = dev_graft_qdisc(dev_queue, new);
152
153 if (dev->flags & IFF_UP)
154 dev_activate(dev);
155 return 0;
156}
157
158static struct Qdisc *mq_leaf(struct Qdisc *sch, unsigned long cl)
159{
160 struct netdev_queue *dev_queue = mq_queue_get(sch, cl);
161
162 return dev_queue->qdisc_sleeping;
163}
164
165static unsigned long mq_get(struct Qdisc *sch, u32 classid)
166{
167 unsigned int ntx = TC_H_MIN(classid);
168
169 if (!mq_queue_get(sch, ntx))
170 return 0;
171 return ntx;
172}
173
174static void mq_put(struct Qdisc *sch, unsigned long cl)
175{
176}
177
178static int mq_dump_class(struct Qdisc *sch, unsigned long cl,
179 struct sk_buff *skb, struct tcmsg *tcm)
180{
181 struct netdev_queue *dev_queue = mq_queue_get(sch, cl);
182
183 tcm->tcm_parent = TC_H_ROOT;
184 tcm->tcm_handle |= TC_H_MIN(cl);
185 tcm->tcm_info = dev_queue->qdisc_sleeping->handle;
186 return 0;
187}
188
189static int mq_dump_class_stats(struct Qdisc *sch, unsigned long cl,
190 struct gnet_dump *d)
191{
192 struct netdev_queue *dev_queue = mq_queue_get(sch, cl);
193
194 sch = dev_queue->qdisc_sleeping;
195 sch->qstats.qlen = sch->q.qlen;
196 if (gnet_stats_copy_basic(d, &sch->bstats) < 0 ||
197 gnet_stats_copy_queue(d, &sch->qstats) < 0)
198 return -1;
199 return 0;
200}
201
202static void mq_walk(struct Qdisc *sch, struct qdisc_walker *arg)
203{
204 struct net_device *dev = qdisc_dev(sch);
205 unsigned int ntx;
206
207 if (arg->stop)
208 return;
209
210 arg->count = arg->skip;
211 for (ntx = arg->skip; ntx < dev->num_tx_queues; ntx++) {
212 if (arg->fn(sch, ntx + 1, arg) < 0) {
213 arg->stop = 1;
214 break;
215 }
216 arg->count++;
217 }
218}
219
220static const struct Qdisc_class_ops mq_class_ops = {
221 .select_queue = mq_select_queue,
222 .graft = mq_graft,
223 .leaf = mq_leaf,
224 .get = mq_get,
225 .put = mq_put,
226 .walk = mq_walk,
227 .dump = mq_dump_class,
228 .dump_stats = mq_dump_class_stats,
229};
230
231struct Qdisc_ops mq_qdisc_ops __read_mostly = {
232 .cl_ops = &mq_class_ops,
233 .id = "mq",
234 .priv_size = sizeof(struct mq_sched),
235 .init = mq_init,
236 .destroy = mq_destroy,
237 .attach = mq_attach,
238 .dump = mq_dump,
239 .owner = THIS_MODULE,
240};