blob: 32690deab5d07cfed26eb7d1fda6656d7d1b8fe0 [file] [log] [blame]
Alexander Duyck92651942008-09-12 16:29:34 -07001/*
2 * Copyright (c) 2008, Intel Corporation.
3 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms and conditions of the GNU General Public License,
6 * version 2, as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope it will be useful, but WITHOUT
9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
11 * more details.
12 *
13 * You should have received a copy of the GNU General Public License along with
14 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
15 * Place - Suite 330, Boston, MA 02111-1307 USA.
16 *
17 * Author: Alexander Duyck <alexander.h.duyck@intel.com>
18 */
19
20#include <linux/module.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090021#include <linux/slab.h>
Alexander Duyck92651942008-09-12 16:29:34 -070022#include <linux/types.h>
23#include <linux/kernel.h>
24#include <linux/string.h>
25#include <linux/errno.h>
26#include <linux/skbuff.h>
27#include <net/netlink.h>
28#include <net/pkt_sched.h>
29
30
31struct multiq_sched_data {
32 u16 bands;
33 u16 max_bands;
34 u16 curband;
35 struct tcf_proto *filter_list;
36 struct Qdisc **queues;
37};
38
39
40static struct Qdisc *
41multiq_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr)
42{
43 struct multiq_sched_data *q = qdisc_priv(sch);
44 u32 band;
45 struct tcf_result res;
46 int err;
47
48 *qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
49 err = tc_classify(skb, q->filter_list, &res);
50#ifdef CONFIG_NET_CLS_ACT
51 switch (err) {
52 case TC_ACT_STOLEN:
53 case TC_ACT_QUEUED:
54 *qerr = NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
55 case TC_ACT_SHOT:
56 return NULL;
57 }
58#endif
59 band = skb_get_queue_mapping(skb);
60
61 if (band >= q->bands)
62 return q->queues[0];
63
64 return q->queues[band];
65}
66
67static int
68multiq_enqueue(struct sk_buff *skb, struct Qdisc *sch)
69{
70 struct Qdisc *qdisc;
71 int ret;
72
73 qdisc = multiq_classify(skb, sch, &ret);
74#ifdef CONFIG_NET_CLS_ACT
75 if (qdisc == NULL) {
76
77 if (ret & __NET_XMIT_BYPASS)
78 sch->qstats.drops++;
79 kfree_skb(skb);
80 return ret;
81 }
82#endif
83
84 ret = qdisc_enqueue(skb, qdisc);
85 if (ret == NET_XMIT_SUCCESS) {
86 sch->bstats.bytes += qdisc_pkt_len(skb);
87 sch->bstats.packets++;
88 sch->q.qlen++;
89 return NET_XMIT_SUCCESS;
90 }
91 if (net_xmit_drop_count(ret))
92 sch->qstats.drops++;
93 return ret;
94}
95
Alexander Duyck92651942008-09-12 16:29:34 -070096static struct sk_buff *multiq_dequeue(struct Qdisc *sch)
97{
98 struct multiq_sched_data *q = qdisc_priv(sch);
99 struct Qdisc *qdisc;
100 struct sk_buff *skb;
101 int band;
102
103 for (band = 0; band < q->bands; band++) {
104 /* cycle through bands to ensure fairness */
105 q->curband++;
106 if (q->curband >= q->bands)
107 q->curband = 0;
108
109 /* Check that target subqueue is available before
Jarek Poplawskif30ab412008-11-13 22:56:30 -0800110 * pulling an skb to avoid head-of-line blocking.
Alexander Duyck92651942008-09-12 16:29:34 -0700111 */
112 if (!__netif_subqueue_stopped(qdisc_dev(sch), q->curband)) {
113 qdisc = q->queues[q->curband];
114 skb = qdisc->dequeue(qdisc);
115 if (skb) {
116 sch->q.qlen--;
117 return skb;
118 }
119 }
120 }
121 return NULL;
122
123}
124
Jarek Poplawski8e3af972008-10-31 00:45:55 -0700125static struct sk_buff *multiq_peek(struct Qdisc *sch)
126{
127 struct multiq_sched_data *q = qdisc_priv(sch);
128 unsigned int curband = q->curband;
129 struct Qdisc *qdisc;
130 struct sk_buff *skb;
131 int band;
132
133 for (band = 0; band < q->bands; band++) {
134 /* cycle through bands to ensure fairness */
135 curband++;
136 if (curband >= q->bands)
137 curband = 0;
138
139 /* Check that target subqueue is available before
Jarek Poplawskif30ab412008-11-13 22:56:30 -0800140 * pulling an skb to avoid head-of-line blocking.
Jarek Poplawski8e3af972008-10-31 00:45:55 -0700141 */
142 if (!__netif_subqueue_stopped(qdisc_dev(sch), curband)) {
143 qdisc = q->queues[curband];
144 skb = qdisc->ops->peek(qdisc);
145 if (skb)
146 return skb;
147 }
148 }
149 return NULL;
150
151}
152
Alexander Duyck92651942008-09-12 16:29:34 -0700153static unsigned int multiq_drop(struct Qdisc *sch)
154{
155 struct multiq_sched_data *q = qdisc_priv(sch);
156 int band;
157 unsigned int len;
158 struct Qdisc *qdisc;
159
160 for (band = q->bands-1; band >= 0; band--) {
161 qdisc = q->queues[band];
162 if (qdisc->ops->drop) {
163 len = qdisc->ops->drop(qdisc);
164 if (len != 0) {
165 sch->q.qlen--;
166 return len;
167 }
168 }
169 }
170 return 0;
171}
172
173
174static void
175multiq_reset(struct Qdisc *sch)
176{
177 u16 band;
178 struct multiq_sched_data *q = qdisc_priv(sch);
179
180 for (band = 0; band < q->bands; band++)
181 qdisc_reset(q->queues[band]);
182 sch->q.qlen = 0;
183 q->curband = 0;
184}
185
186static void
187multiq_destroy(struct Qdisc *sch)
188{
189 int band;
190 struct multiq_sched_data *q = qdisc_priv(sch);
191
192 tcf_destroy_chain(&q->filter_list);
193 for (band = 0; band < q->bands; band++)
194 qdisc_destroy(q->queues[band]);
195
196 kfree(q->queues);
197}
198
199static int multiq_tune(struct Qdisc *sch, struct nlattr *opt)
200{
201 struct multiq_sched_data *q = qdisc_priv(sch);
202 struct tc_multiq_qopt *qopt;
203 int i;
204
205 if (!netif_is_multiqueue(qdisc_dev(sch)))
Jarek Poplawski149490f2009-02-10 00:11:21 -0800206 return -EOPNOTSUPP;
Alexander Duyck92651942008-09-12 16:29:34 -0700207 if (nla_len(opt) < sizeof(*qopt))
208 return -EINVAL;
209
210 qopt = nla_data(opt);
211
212 qopt->bands = qdisc_dev(sch)->real_num_tx_queues;
213
214 sch_tree_lock(sch);
215 q->bands = qopt->bands;
216 for (i = q->bands; i < q->max_bands; i++) {
Alexander Duyckf07d1502008-09-12 17:57:23 -0700217 if (q->queues[i] != &noop_qdisc) {
Patrick McHardyb94c8af2008-11-20 04:11:36 -0800218 struct Qdisc *child = q->queues[i];
219 q->queues[i] = &noop_qdisc;
Alexander Duyck92651942008-09-12 16:29:34 -0700220 qdisc_tree_decrease_qlen(child, child->q.qlen);
221 qdisc_destroy(child);
222 }
223 }
224
225 sch_tree_unlock(sch);
226
227 for (i = 0; i < q->bands; i++) {
228 if (q->queues[i] == &noop_qdisc) {
Patrick McHardyb94c8af2008-11-20 04:11:36 -0800229 struct Qdisc *child, *old;
Changli Gao3511c912010-10-16 13:04:08 +0000230 child = qdisc_create_dflt(sch->dev_queue,
Alexander Duyck92651942008-09-12 16:29:34 -0700231 &pfifo_qdisc_ops,
232 TC_H_MAKE(sch->handle,
233 i + 1));
234 if (child) {
235 sch_tree_lock(sch);
Patrick McHardyb94c8af2008-11-20 04:11:36 -0800236 old = q->queues[i];
237 q->queues[i] = child;
Alexander Duyck92651942008-09-12 16:29:34 -0700238
Patrick McHardyb94c8af2008-11-20 04:11:36 -0800239 if (old != &noop_qdisc) {
240 qdisc_tree_decrease_qlen(old,
241 old->q.qlen);
242 qdisc_destroy(old);
Alexander Duyck92651942008-09-12 16:29:34 -0700243 }
244 sch_tree_unlock(sch);
245 }
246 }
247 }
248 return 0;
249}
250
251static int multiq_init(struct Qdisc *sch, struct nlattr *opt)
252{
253 struct multiq_sched_data *q = qdisc_priv(sch);
Alexander Duyckf07d1502008-09-12 17:57:23 -0700254 int i, err;
Alexander Duyck92651942008-09-12 16:29:34 -0700255
256 q->queues = NULL;
257
258 if (opt == NULL)
259 return -EINVAL;
260
261 q->max_bands = qdisc_dev(sch)->num_tx_queues;
262
263 q->queues = kcalloc(q->max_bands, sizeof(struct Qdisc *), GFP_KERNEL);
264 if (!q->queues)
265 return -ENOBUFS;
266 for (i = 0; i < q->max_bands; i++)
267 q->queues[i] = &noop_qdisc;
268
Alexander Duyckf07d1502008-09-12 17:57:23 -0700269 err = multiq_tune(sch,opt);
270
271 if (err)
272 kfree(q->queues);
273
274 return err;
Alexander Duyck92651942008-09-12 16:29:34 -0700275}
276
277static int multiq_dump(struct Qdisc *sch, struct sk_buff *skb)
278{
279 struct multiq_sched_data *q = qdisc_priv(sch);
280 unsigned char *b = skb_tail_pointer(skb);
281 struct tc_multiq_qopt opt;
282
283 opt.bands = q->bands;
284 opt.max_bands = q->max_bands;
285
286 NLA_PUT(skb, TCA_OPTIONS, sizeof(opt), &opt);
287
288 return skb->len;
289
290nla_put_failure:
291 nlmsg_trim(skb, b);
292 return -1;
293}
294
295static int multiq_graft(struct Qdisc *sch, unsigned long arg, struct Qdisc *new,
296 struct Qdisc **old)
297{
298 struct multiq_sched_data *q = qdisc_priv(sch);
299 unsigned long band = arg - 1;
300
Alexander Duyck92651942008-09-12 16:29:34 -0700301 if (new == NULL)
302 new = &noop_qdisc;
303
304 sch_tree_lock(sch);
305 *old = q->queues[band];
306 q->queues[band] = new;
307 qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
308 qdisc_reset(*old);
309 sch_tree_unlock(sch);
310
311 return 0;
312}
313
314static struct Qdisc *
315multiq_leaf(struct Qdisc *sch, unsigned long arg)
316{
317 struct multiq_sched_data *q = qdisc_priv(sch);
318 unsigned long band = arg - 1;
319
Alexander Duyck92651942008-09-12 16:29:34 -0700320 return q->queues[band];
321}
322
323static unsigned long multiq_get(struct Qdisc *sch, u32 classid)
324{
325 struct multiq_sched_data *q = qdisc_priv(sch);
326 unsigned long band = TC_H_MIN(classid);
327
328 if (band - 1 >= q->bands)
329 return 0;
330 return band;
331}
332
333static unsigned long multiq_bind(struct Qdisc *sch, unsigned long parent,
334 u32 classid)
335{
336 return multiq_get(sch, classid);
337}
338
339
340static void multiq_put(struct Qdisc *q, unsigned long cl)
341{
Alexander Duyck92651942008-09-12 16:29:34 -0700342}
343
Alexander Duyck92651942008-09-12 16:29:34 -0700344static int multiq_dump_class(struct Qdisc *sch, unsigned long cl,
345 struct sk_buff *skb, struct tcmsg *tcm)
346{
347 struct multiq_sched_data *q = qdisc_priv(sch);
348
Alexander Duyck92651942008-09-12 16:29:34 -0700349 tcm->tcm_handle |= TC_H_MIN(cl);
Patrick McHardy5b9a9cc2009-09-04 06:41:17 +0000350 tcm->tcm_info = q->queues[cl-1]->handle;
Alexander Duyck92651942008-09-12 16:29:34 -0700351 return 0;
352}
353
354static int multiq_dump_class_stats(struct Qdisc *sch, unsigned long cl,
355 struct gnet_dump *d)
356{
357 struct multiq_sched_data *q = qdisc_priv(sch);
358 struct Qdisc *cl_q;
359
360 cl_q = q->queues[cl - 1];
Jarek Poplawskia19d2152009-09-17 10:26:07 -0700361 cl_q->qstats.qlen = cl_q->q.qlen;
Alexander Duyck92651942008-09-12 16:29:34 -0700362 if (gnet_stats_copy_basic(d, &cl_q->bstats) < 0 ||
363 gnet_stats_copy_queue(d, &cl_q->qstats) < 0)
364 return -1;
365
366 return 0;
367}
368
369static void multiq_walk(struct Qdisc *sch, struct qdisc_walker *arg)
370{
371 struct multiq_sched_data *q = qdisc_priv(sch);
372 int band;
373
374 if (arg->stop)
375 return;
376
377 for (band = 0; band < q->bands; band++) {
378 if (arg->count < arg->skip) {
379 arg->count++;
380 continue;
381 }
382 if (arg->fn(sch, band+1, arg) < 0) {
383 arg->stop = 1;
384 break;
385 }
386 arg->count++;
387 }
388}
389
390static struct tcf_proto **multiq_find_tcf(struct Qdisc *sch, unsigned long cl)
391{
392 struct multiq_sched_data *q = qdisc_priv(sch);
393
394 if (cl)
395 return NULL;
396 return &q->filter_list;
397}
398
399static const struct Qdisc_class_ops multiq_class_ops = {
400 .graft = multiq_graft,
401 .leaf = multiq_leaf,
402 .get = multiq_get,
403 .put = multiq_put,
Alexander Duyck92651942008-09-12 16:29:34 -0700404 .walk = multiq_walk,
405 .tcf_chain = multiq_find_tcf,
406 .bind_tcf = multiq_bind,
407 .unbind_tcf = multiq_put,
408 .dump = multiq_dump_class,
409 .dump_stats = multiq_dump_class_stats,
410};
411
412static struct Qdisc_ops multiq_qdisc_ops __read_mostly = {
413 .next = NULL,
414 .cl_ops = &multiq_class_ops,
415 .id = "multiq",
416 .priv_size = sizeof(struct multiq_sched_data),
417 .enqueue = multiq_enqueue,
418 .dequeue = multiq_dequeue,
Jarek Poplawski8e3af972008-10-31 00:45:55 -0700419 .peek = multiq_peek,
Alexander Duyck92651942008-09-12 16:29:34 -0700420 .drop = multiq_drop,
421 .init = multiq_init,
422 .reset = multiq_reset,
423 .destroy = multiq_destroy,
424 .change = multiq_tune,
425 .dump = multiq_dump,
426 .owner = THIS_MODULE,
427};
428
429static int __init multiq_module_init(void)
430{
431 return register_qdisc(&multiq_qdisc_ops);
432}
433
434static void __exit multiq_module_exit(void)
435{
436 unregister_qdisc(&multiq_qdisc_ops);
437}
438
439module_init(multiq_module_init)
440module_exit(multiq_module_exit)
441
442MODULE_LICENSE("GPL");