blob: 49131d7a7446eafb22c121ce987f0fd7e4e233a5 [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) {
Alexander Duyck92651942008-09-12 16:29:34 -070086 sch->q.qlen++;
87 return NET_XMIT_SUCCESS;
88 }
89 if (net_xmit_drop_count(ret))
90 sch->qstats.drops++;
91 return ret;
92}
93
Alexander Duyck92651942008-09-12 16:29:34 -070094static struct sk_buff *multiq_dequeue(struct Qdisc *sch)
95{
96 struct multiq_sched_data *q = qdisc_priv(sch);
97 struct Qdisc *qdisc;
98 struct sk_buff *skb;
99 int band;
100
101 for (band = 0; band < q->bands; band++) {
102 /* cycle through bands to ensure fairness */
103 q->curband++;
104 if (q->curband >= q->bands)
105 q->curband = 0;
106
107 /* Check that target subqueue is available before
Jarek Poplawskif30ab412008-11-13 22:56:30 -0800108 * pulling an skb to avoid head-of-line blocking.
Alexander Duyck92651942008-09-12 16:29:34 -0700109 */
Tom Herbert734664982011-11-28 16:32:44 +0000110 if (!netif_xmit_stopped(
111 netdev_get_tx_queue(qdisc_dev(sch), q->curband))) {
Alexander Duyck92651942008-09-12 16:29:34 -0700112 qdisc = q->queues[q->curband];
113 skb = qdisc->dequeue(qdisc);
114 if (skb) {
Eric Dumazet9190b3b2011-01-20 23:31:33 -0800115 qdisc_bstats_update(sch, skb);
Alexander Duyck92651942008-09-12 16:29:34 -0700116 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 */
Tom Herbert734664982011-11-28 16:32:44 +0000142 if (!netif_xmit_stopped(
143 netdev_get_tx_queue(qdisc_dev(sch), curband))) {
Jarek Poplawski8e3af972008-10-31 00:45:55 -0700144 qdisc = q->queues[curband];
145 skb = qdisc->ops->peek(qdisc);
146 if (skb)
147 return skb;
148 }
149 }
150 return NULL;
151
152}
153
Alexander Duyck92651942008-09-12 16:29:34 -0700154static unsigned int multiq_drop(struct Qdisc *sch)
155{
156 struct multiq_sched_data *q = qdisc_priv(sch);
157 int band;
158 unsigned int len;
159 struct Qdisc *qdisc;
160
Eric Dumazetcc7ec452011-01-19 19:26:56 +0000161 for (band = q->bands - 1; band >= 0; band--) {
Alexander Duyck92651942008-09-12 16:29:34 -0700162 qdisc = q->queues[band];
163 if (qdisc->ops->drop) {
164 len = qdisc->ops->drop(qdisc);
165 if (len != 0) {
166 sch->q.qlen--;
167 return len;
168 }
169 }
170 }
171 return 0;
172}
173
174
175static void
176multiq_reset(struct Qdisc *sch)
177{
178 u16 band;
179 struct multiq_sched_data *q = qdisc_priv(sch);
180
181 for (band = 0; band < q->bands; band++)
182 qdisc_reset(q->queues[band]);
183 sch->q.qlen = 0;
184 q->curband = 0;
185}
186
187static void
188multiq_destroy(struct Qdisc *sch)
189{
190 int band;
191 struct multiq_sched_data *q = qdisc_priv(sch);
192
193 tcf_destroy_chain(&q->filter_list);
194 for (band = 0; band < q->bands; band++)
195 qdisc_destroy(q->queues[band]);
196
197 kfree(q->queues);
198}
199
200static int multiq_tune(struct Qdisc *sch, struct nlattr *opt)
201{
202 struct multiq_sched_data *q = qdisc_priv(sch);
203 struct tc_multiq_qopt *qopt;
204 int i;
205
206 if (!netif_is_multiqueue(qdisc_dev(sch)))
Jarek Poplawski149490f2009-02-10 00:11:21 -0800207 return -EOPNOTSUPP;
Alexander Duyck92651942008-09-12 16:29:34 -0700208 if (nla_len(opt) < sizeof(*qopt))
209 return -EINVAL;
210
211 qopt = nla_data(opt);
212
213 qopt->bands = qdisc_dev(sch)->real_num_tx_queues;
214
215 sch_tree_lock(sch);
216 q->bands = qopt->bands;
217 for (i = q->bands; i < q->max_bands; i++) {
Alexander Duyckf07d1502008-09-12 17:57:23 -0700218 if (q->queues[i] != &noop_qdisc) {
Patrick McHardyb94c8af2008-11-20 04:11:36 -0800219 struct Qdisc *child = q->queues[i];
220 q->queues[i] = &noop_qdisc;
Alexander Duyck92651942008-09-12 16:29:34 -0700221 qdisc_tree_decrease_qlen(child, child->q.qlen);
222 qdisc_destroy(child);
223 }
224 }
225
226 sch_tree_unlock(sch);
227
228 for (i = 0; i < q->bands; i++) {
229 if (q->queues[i] == &noop_qdisc) {
Patrick McHardyb94c8af2008-11-20 04:11:36 -0800230 struct Qdisc *child, *old;
Changli Gao3511c912010-10-16 13:04:08 +0000231 child = qdisc_create_dflt(sch->dev_queue,
Alexander Duyck92651942008-09-12 16:29:34 -0700232 &pfifo_qdisc_ops,
233 TC_H_MAKE(sch->handle,
234 i + 1));
235 if (child) {
236 sch_tree_lock(sch);
Patrick McHardyb94c8af2008-11-20 04:11:36 -0800237 old = q->queues[i];
238 q->queues[i] = child;
Alexander Duyck92651942008-09-12 16:29:34 -0700239
Patrick McHardyb94c8af2008-11-20 04:11:36 -0800240 if (old != &noop_qdisc) {
241 qdisc_tree_decrease_qlen(old,
242 old->q.qlen);
243 qdisc_destroy(old);
Alexander Duyck92651942008-09-12 16:29:34 -0700244 }
245 sch_tree_unlock(sch);
246 }
247 }
248 }
249 return 0;
250}
251
252static int multiq_init(struct Qdisc *sch, struct nlattr *opt)
253{
254 struct multiq_sched_data *q = qdisc_priv(sch);
Alexander Duyckf07d1502008-09-12 17:57:23 -0700255 int i, err;
Alexander Duyck92651942008-09-12 16:29:34 -0700256
257 q->queues = NULL;
258
259 if (opt == NULL)
260 return -EINVAL;
261
262 q->max_bands = qdisc_dev(sch)->num_tx_queues;
263
264 q->queues = kcalloc(q->max_bands, sizeof(struct Qdisc *), GFP_KERNEL);
265 if (!q->queues)
266 return -ENOBUFS;
267 for (i = 0; i < q->max_bands; i++)
268 q->queues[i] = &noop_qdisc;
269
Eric Dumazetcc7ec452011-01-19 19:26:56 +0000270 err = multiq_tune(sch, opt);
Alexander Duyckf07d1502008-09-12 17:57:23 -0700271
272 if (err)
273 kfree(q->queues);
274
275 return err;
Alexander Duyck92651942008-09-12 16:29:34 -0700276}
277
278static int multiq_dump(struct Qdisc *sch, struct sk_buff *skb)
279{
280 struct multiq_sched_data *q = qdisc_priv(sch);
281 unsigned char *b = skb_tail_pointer(skb);
282 struct tc_multiq_qopt opt;
283
284 opt.bands = q->bands;
285 opt.max_bands = q->max_bands;
286
287 NLA_PUT(skb, TCA_OPTIONS, sizeof(opt), &opt);
288
289 return skb->len;
290
291nla_put_failure:
292 nlmsg_trim(skb, b);
293 return -1;
294}
295
296static int multiq_graft(struct Qdisc *sch, unsigned long arg, struct Qdisc *new,
297 struct Qdisc **old)
298{
299 struct multiq_sched_data *q = qdisc_priv(sch);
300 unsigned long band = arg - 1;
301
Alexander Duyck92651942008-09-12 16:29:34 -0700302 if (new == NULL)
303 new = &noop_qdisc;
304
305 sch_tree_lock(sch);
306 *old = q->queues[band];
307 q->queues[band] = new;
308 qdisc_tree_decrease_qlen(*old, (*old)->q.qlen);
309 qdisc_reset(*old);
310 sch_tree_unlock(sch);
311
312 return 0;
313}
314
315static struct Qdisc *
316multiq_leaf(struct Qdisc *sch, unsigned long arg)
317{
318 struct multiq_sched_data *q = qdisc_priv(sch);
319 unsigned long band = arg - 1;
320
Alexander Duyck92651942008-09-12 16:29:34 -0700321 return q->queues[band];
322}
323
324static unsigned long multiq_get(struct Qdisc *sch, u32 classid)
325{
326 struct multiq_sched_data *q = qdisc_priv(sch);
327 unsigned long band = TC_H_MIN(classid);
328
329 if (band - 1 >= q->bands)
330 return 0;
331 return band;
332}
333
334static unsigned long multiq_bind(struct Qdisc *sch, unsigned long parent,
335 u32 classid)
336{
337 return multiq_get(sch, classid);
338}
339
340
341static void multiq_put(struct Qdisc *q, unsigned long cl)
342{
Alexander Duyck92651942008-09-12 16:29:34 -0700343}
344
Alexander Duyck92651942008-09-12 16:29:34 -0700345static int multiq_dump_class(struct Qdisc *sch, unsigned long cl,
346 struct sk_buff *skb, struct tcmsg *tcm)
347{
348 struct multiq_sched_data *q = qdisc_priv(sch);
349
Alexander Duyck92651942008-09-12 16:29:34 -0700350 tcm->tcm_handle |= TC_H_MIN(cl);
Eric Dumazetcc7ec452011-01-19 19:26:56 +0000351 tcm->tcm_info = q->queues[cl - 1]->handle;
Alexander Duyck92651942008-09-12 16:29:34 -0700352 return 0;
353}
354
355static int multiq_dump_class_stats(struct Qdisc *sch, unsigned long cl,
356 struct gnet_dump *d)
357{
358 struct multiq_sched_data *q = qdisc_priv(sch);
359 struct Qdisc *cl_q;
360
361 cl_q = q->queues[cl - 1];
Jarek Poplawskia19d2152009-09-17 10:26:07 -0700362 cl_q->qstats.qlen = cl_q->q.qlen;
Alexander Duyck92651942008-09-12 16:29:34 -0700363 if (gnet_stats_copy_basic(d, &cl_q->bstats) < 0 ||
364 gnet_stats_copy_queue(d, &cl_q->qstats) < 0)
365 return -1;
366
367 return 0;
368}
369
370static void multiq_walk(struct Qdisc *sch, struct qdisc_walker *arg)
371{
372 struct multiq_sched_data *q = qdisc_priv(sch);
373 int band;
374
375 if (arg->stop)
376 return;
377
378 for (band = 0; band < q->bands; band++) {
379 if (arg->count < arg->skip) {
380 arg->count++;
381 continue;
382 }
Eric Dumazetcc7ec452011-01-19 19:26:56 +0000383 if (arg->fn(sch, band + 1, arg) < 0) {
Alexander Duyck92651942008-09-12 16:29:34 -0700384 arg->stop = 1;
385 break;
386 }
387 arg->count++;
388 }
389}
390
391static struct tcf_proto **multiq_find_tcf(struct Qdisc *sch, unsigned long cl)
392{
393 struct multiq_sched_data *q = qdisc_priv(sch);
394
395 if (cl)
396 return NULL;
397 return &q->filter_list;
398}
399
400static const struct Qdisc_class_ops multiq_class_ops = {
401 .graft = multiq_graft,
402 .leaf = multiq_leaf,
403 .get = multiq_get,
404 .put = multiq_put,
Alexander Duyck92651942008-09-12 16:29:34 -0700405 .walk = multiq_walk,
406 .tcf_chain = multiq_find_tcf,
407 .bind_tcf = multiq_bind,
408 .unbind_tcf = multiq_put,
409 .dump = multiq_dump_class,
410 .dump_stats = multiq_dump_class_stats,
411};
412
413static struct Qdisc_ops multiq_qdisc_ops __read_mostly = {
414 .next = NULL,
415 .cl_ops = &multiq_class_ops,
416 .id = "multiq",
417 .priv_size = sizeof(struct multiq_sched_data),
418 .enqueue = multiq_enqueue,
419 .dequeue = multiq_dequeue,
Jarek Poplawski8e3af972008-10-31 00:45:55 -0700420 .peek = multiq_peek,
Alexander Duyck92651942008-09-12 16:29:34 -0700421 .drop = multiq_drop,
422 .init = multiq_init,
423 .reset = multiq_reset,
424 .destroy = multiq_destroy,
425 .change = multiq_tune,
426 .dump = multiq_dump,
427 .owner = THIS_MODULE,
428};
429
430static int __init multiq_module_init(void)
431{
432 return register_qdisc(&multiq_qdisc_ops);
433}
434
435static void __exit multiq_module_exit(void)
436{
437 unregister_qdisc(&multiq_qdisc_ops);
438}
439
440module_init(multiq_module_init)
441module_exit(multiq_module_exit)
442
443MODULE_LICENSE("GPL");