blob: d1dea3d5dc929f1dc2051b2ed42f65168c88aa09 [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>
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
19struct mq_sched {
20 struct Qdisc **qdiscs;
21};
22
23static 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
36static 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
Patrick McHardy23bcf632009-09-09 18:11:23 -070067 sch->flags |= TCQ_F_MQROOT;
David S. Miller6ec1c692009-09-06 01:58:51 -070068 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
Jarek Poplawski926e61b2009-09-15 02:53:07 -0700128static struct netdev_queue *mq_select_queue(struct Qdisc *sch,
129 struct tcmsg *tcm)
David S. Miller6ec1c692009-09-06 01:58:51 -0700130{
131 unsigned int ntx = TC_H_MIN(tcm->tcm_parent);
Jarek Poplawski926e61b2009-09-15 02:53:07 -0700132 struct netdev_queue *dev_queue = mq_queue_get(sch, ntx);
David S. Miller6ec1c692009-09-06 01:58:51 -0700133
Jarek Poplawski926e61b2009-09-15 02:53:07 -0700134 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;
David S. Miller6ec1c692009-09-06 01:58:51 -0700140}
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 return;
177}
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};