Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
[cris-mirror.git] / net / sched / sch_mqprio.c
blob0e9d761cdd80a18bdfc824503dcd8e5a8ee5c596
1 /*
2 * net/sched/sch_mqprio.c
4 * Copyright (c) 2010 John Fastabend <john.r.fastabend@intel.com>
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 */
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 <linux/module.h>
18 #include <net/netlink.h>
19 #include <net/pkt_sched.h>
20 #include <net/sch_generic.h>
21 #include <net/pkt_cls.h>
23 struct mqprio_sched {
24 struct Qdisc **qdiscs;
25 u16 mode;
26 u16 shaper;
27 int hw_offload;
28 u32 flags;
29 u64 min_rate[TC_QOPT_MAX_QUEUE];
30 u64 max_rate[TC_QOPT_MAX_QUEUE];
33 static void mqprio_destroy(struct Qdisc *sch)
35 struct net_device *dev = qdisc_dev(sch);
36 struct mqprio_sched *priv = qdisc_priv(sch);
37 unsigned int ntx;
39 if (priv->qdiscs) {
40 for (ntx = 0;
41 ntx < dev->num_tx_queues && priv->qdiscs[ntx];
42 ntx++)
43 qdisc_destroy(priv->qdiscs[ntx]);
44 kfree(priv->qdiscs);
47 if (priv->hw_offload && dev->netdev_ops->ndo_setup_tc) {
48 struct tc_mqprio_qopt_offload mqprio = { { 0 } };
50 switch (priv->mode) {
51 case TC_MQPRIO_MODE_DCB:
52 case TC_MQPRIO_MODE_CHANNEL:
53 dev->netdev_ops->ndo_setup_tc(dev,
54 TC_SETUP_QDISC_MQPRIO,
55 &mqprio);
56 break;
57 default:
58 return;
60 } else {
61 netdev_set_num_tc(dev, 0);
65 static int mqprio_parse_opt(struct net_device *dev, struct tc_mqprio_qopt *qopt)
67 int i, j;
69 /* Verify num_tc is not out of max range */
70 if (qopt->num_tc > TC_MAX_QUEUE)
71 return -EINVAL;
73 /* Verify priority mapping uses valid tcs */
74 for (i = 0; i < TC_BITMASK + 1; i++) {
75 if (qopt->prio_tc_map[i] >= qopt->num_tc)
76 return -EINVAL;
79 /* Limit qopt->hw to maximum supported offload value. Drivers have
80 * the option of overriding this later if they don't support the a
81 * given offload type.
83 if (qopt->hw > TC_MQPRIO_HW_OFFLOAD_MAX)
84 qopt->hw = TC_MQPRIO_HW_OFFLOAD_MAX;
86 /* If hardware offload is requested we will leave it to the device
87 * to either populate the queue counts itself or to validate the
88 * provided queue counts. If ndo_setup_tc is not present then
89 * hardware doesn't support offload and we should return an error.
91 if (qopt->hw)
92 return dev->netdev_ops->ndo_setup_tc ? 0 : -EINVAL;
94 for (i = 0; i < qopt->num_tc; i++) {
95 unsigned int last = qopt->offset[i] + qopt->count[i];
97 /* Verify the queue count is in tx range being equal to the
98 * real_num_tx_queues indicates the last queue is in use.
100 if (qopt->offset[i] >= dev->real_num_tx_queues ||
101 !qopt->count[i] ||
102 last > dev->real_num_tx_queues)
103 return -EINVAL;
105 /* Verify that the offset and counts do not overlap */
106 for (j = i + 1; j < qopt->num_tc; j++) {
107 if (last > qopt->offset[j])
108 return -EINVAL;
112 return 0;
115 static const struct nla_policy mqprio_policy[TCA_MQPRIO_MAX + 1] = {
116 [TCA_MQPRIO_MODE] = { .len = sizeof(u16) },
117 [TCA_MQPRIO_SHAPER] = { .len = sizeof(u16) },
118 [TCA_MQPRIO_MIN_RATE64] = { .type = NLA_NESTED },
119 [TCA_MQPRIO_MAX_RATE64] = { .type = NLA_NESTED },
122 static int parse_attr(struct nlattr *tb[], int maxtype, struct nlattr *nla,
123 const struct nla_policy *policy, int len)
125 int nested_len = nla_len(nla) - NLA_ALIGN(len);
127 if (nested_len >= nla_attr_size(0))
128 return nla_parse(tb, maxtype, nla_data(nla) + NLA_ALIGN(len),
129 nested_len, policy, NULL);
131 memset(tb, 0, sizeof(struct nlattr *) * (maxtype + 1));
132 return 0;
135 static int mqprio_init(struct Qdisc *sch, struct nlattr *opt,
136 struct netlink_ext_ack *extack)
138 struct net_device *dev = qdisc_dev(sch);
139 struct mqprio_sched *priv = qdisc_priv(sch);
140 struct netdev_queue *dev_queue;
141 struct Qdisc *qdisc;
142 int i, err = -EOPNOTSUPP;
143 struct tc_mqprio_qopt *qopt = NULL;
144 struct nlattr *tb[TCA_MQPRIO_MAX + 1];
145 struct nlattr *attr;
146 int rem;
147 int len;
149 BUILD_BUG_ON(TC_MAX_QUEUE != TC_QOPT_MAX_QUEUE);
150 BUILD_BUG_ON(TC_BITMASK != TC_QOPT_BITMASK);
152 if (sch->parent != TC_H_ROOT)
153 return -EOPNOTSUPP;
155 if (!netif_is_multiqueue(dev))
156 return -EOPNOTSUPP;
158 /* make certain can allocate enough classids to handle queues */
159 if (dev->num_tx_queues >= TC_H_MIN_PRIORITY)
160 return -ENOMEM;
162 if (!opt || nla_len(opt) < sizeof(*qopt))
163 return -EINVAL;
165 qopt = nla_data(opt);
166 if (mqprio_parse_opt(dev, qopt))
167 return -EINVAL;
169 len = nla_len(opt) - NLA_ALIGN(sizeof(*qopt));
170 if (len > 0) {
171 err = parse_attr(tb, TCA_MQPRIO_MAX, opt, mqprio_policy,
172 sizeof(*qopt));
173 if (err < 0)
174 return err;
176 if (!qopt->hw)
177 return -EINVAL;
179 if (tb[TCA_MQPRIO_MODE]) {
180 priv->flags |= TC_MQPRIO_F_MODE;
181 priv->mode = *(u16 *)nla_data(tb[TCA_MQPRIO_MODE]);
184 if (tb[TCA_MQPRIO_SHAPER]) {
185 priv->flags |= TC_MQPRIO_F_SHAPER;
186 priv->shaper = *(u16 *)nla_data(tb[TCA_MQPRIO_SHAPER]);
189 if (tb[TCA_MQPRIO_MIN_RATE64]) {
190 if (priv->shaper != TC_MQPRIO_SHAPER_BW_RATE)
191 return -EINVAL;
192 i = 0;
193 nla_for_each_nested(attr, tb[TCA_MQPRIO_MIN_RATE64],
194 rem) {
195 if (nla_type(attr) != TCA_MQPRIO_MIN_RATE64)
196 return -EINVAL;
197 if (i >= qopt->num_tc)
198 break;
199 priv->min_rate[i] = *(u64 *)nla_data(attr);
200 i++;
202 priv->flags |= TC_MQPRIO_F_MIN_RATE;
205 if (tb[TCA_MQPRIO_MAX_RATE64]) {
206 if (priv->shaper != TC_MQPRIO_SHAPER_BW_RATE)
207 return -EINVAL;
208 i = 0;
209 nla_for_each_nested(attr, tb[TCA_MQPRIO_MAX_RATE64],
210 rem) {
211 if (nla_type(attr) != TCA_MQPRIO_MAX_RATE64)
212 return -EINVAL;
213 if (i >= qopt->num_tc)
214 break;
215 priv->max_rate[i] = *(u64 *)nla_data(attr);
216 i++;
218 priv->flags |= TC_MQPRIO_F_MAX_RATE;
222 /* pre-allocate qdisc, attachment can't fail */
223 priv->qdiscs = kcalloc(dev->num_tx_queues, sizeof(priv->qdiscs[0]),
224 GFP_KERNEL);
225 if (!priv->qdiscs)
226 return -ENOMEM;
228 for (i = 0; i < dev->num_tx_queues; i++) {
229 dev_queue = netdev_get_tx_queue(dev, i);
230 qdisc = qdisc_create_dflt(dev_queue,
231 get_default_qdisc_ops(dev, i),
232 TC_H_MAKE(TC_H_MAJ(sch->handle),
233 TC_H_MIN(i + 1)), extack);
234 if (!qdisc)
235 return -ENOMEM;
237 priv->qdiscs[i] = qdisc;
238 qdisc->flags |= TCQ_F_ONETXQUEUE | TCQ_F_NOPARENT;
241 /* If the mqprio options indicate that hardware should own
242 * the queue mapping then run ndo_setup_tc otherwise use the
243 * supplied and verified mapping
245 if (qopt->hw) {
246 struct tc_mqprio_qopt_offload mqprio = {.qopt = *qopt};
248 switch (priv->mode) {
249 case TC_MQPRIO_MODE_DCB:
250 if (priv->shaper != TC_MQPRIO_SHAPER_DCB)
251 return -EINVAL;
252 break;
253 case TC_MQPRIO_MODE_CHANNEL:
254 mqprio.flags = priv->flags;
255 if (priv->flags & TC_MQPRIO_F_MODE)
256 mqprio.mode = priv->mode;
257 if (priv->flags & TC_MQPRIO_F_SHAPER)
258 mqprio.shaper = priv->shaper;
259 if (priv->flags & TC_MQPRIO_F_MIN_RATE)
260 for (i = 0; i < mqprio.qopt.num_tc; i++)
261 mqprio.min_rate[i] = priv->min_rate[i];
262 if (priv->flags & TC_MQPRIO_F_MAX_RATE)
263 for (i = 0; i < mqprio.qopt.num_tc; i++)
264 mqprio.max_rate[i] = priv->max_rate[i];
265 break;
266 default:
267 return -EINVAL;
269 err = dev->netdev_ops->ndo_setup_tc(dev,
270 TC_SETUP_QDISC_MQPRIO,
271 &mqprio);
272 if (err)
273 return err;
275 priv->hw_offload = mqprio.qopt.hw;
276 } else {
277 netdev_set_num_tc(dev, qopt->num_tc);
278 for (i = 0; i < qopt->num_tc; i++)
279 netdev_set_tc_queue(dev, i,
280 qopt->count[i], qopt->offset[i]);
283 /* Always use supplied priority mappings */
284 for (i = 0; i < TC_BITMASK + 1; i++)
285 netdev_set_prio_tc_map(dev, i, qopt->prio_tc_map[i]);
287 sch->flags |= TCQ_F_MQROOT;
288 return 0;
291 static void mqprio_attach(struct Qdisc *sch)
293 struct net_device *dev = qdisc_dev(sch);
294 struct mqprio_sched *priv = qdisc_priv(sch);
295 struct Qdisc *qdisc, *old;
296 unsigned int ntx;
298 /* Attach underlying qdisc */
299 for (ntx = 0; ntx < dev->num_tx_queues; ntx++) {
300 qdisc = priv->qdiscs[ntx];
301 old = dev_graft_qdisc(qdisc->dev_queue, qdisc);
302 if (old)
303 qdisc_destroy(old);
304 if (ntx < dev->real_num_tx_queues)
305 qdisc_hash_add(qdisc, false);
307 kfree(priv->qdiscs);
308 priv->qdiscs = NULL;
311 static struct netdev_queue *mqprio_queue_get(struct Qdisc *sch,
312 unsigned long cl)
314 struct net_device *dev = qdisc_dev(sch);
315 unsigned long ntx = cl - 1;
317 if (ntx >= dev->num_tx_queues)
318 return NULL;
319 return netdev_get_tx_queue(dev, ntx);
322 static int mqprio_graft(struct Qdisc *sch, unsigned long cl, struct Qdisc *new,
323 struct Qdisc **old, struct netlink_ext_ack *extack)
325 struct net_device *dev = qdisc_dev(sch);
326 struct netdev_queue *dev_queue = mqprio_queue_get(sch, cl);
328 if (!dev_queue)
329 return -EINVAL;
331 if (dev->flags & IFF_UP)
332 dev_deactivate(dev);
334 *old = dev_graft_qdisc(dev_queue, new);
336 if (new)
337 new->flags |= TCQ_F_ONETXQUEUE | TCQ_F_NOPARENT;
339 if (dev->flags & IFF_UP)
340 dev_activate(dev);
342 return 0;
345 static int dump_rates(struct mqprio_sched *priv,
346 struct tc_mqprio_qopt *opt, struct sk_buff *skb)
348 struct nlattr *nest;
349 int i;
351 if (priv->flags & TC_MQPRIO_F_MIN_RATE) {
352 nest = nla_nest_start(skb, TCA_MQPRIO_MIN_RATE64);
353 if (!nest)
354 goto nla_put_failure;
356 for (i = 0; i < opt->num_tc; i++) {
357 if (nla_put(skb, TCA_MQPRIO_MIN_RATE64,
358 sizeof(priv->min_rate[i]),
359 &priv->min_rate[i]))
360 goto nla_put_failure;
362 nla_nest_end(skb, nest);
365 if (priv->flags & TC_MQPRIO_F_MAX_RATE) {
366 nest = nla_nest_start(skb, TCA_MQPRIO_MAX_RATE64);
367 if (!nest)
368 goto nla_put_failure;
370 for (i = 0; i < opt->num_tc; i++) {
371 if (nla_put(skb, TCA_MQPRIO_MAX_RATE64,
372 sizeof(priv->max_rate[i]),
373 &priv->max_rate[i]))
374 goto nla_put_failure;
376 nla_nest_end(skb, nest);
378 return 0;
380 nla_put_failure:
381 nla_nest_cancel(skb, nest);
382 return -1;
385 static int mqprio_dump(struct Qdisc *sch, struct sk_buff *skb)
387 struct net_device *dev = qdisc_dev(sch);
388 struct mqprio_sched *priv = qdisc_priv(sch);
389 struct nlattr *nla = (struct nlattr *)skb_tail_pointer(skb);
390 struct tc_mqprio_qopt opt = { 0 };
391 struct Qdisc *qdisc;
392 unsigned int ntx, tc;
394 sch->q.qlen = 0;
395 memset(&sch->bstats, 0, sizeof(sch->bstats));
396 memset(&sch->qstats, 0, sizeof(sch->qstats));
398 /* MQ supports lockless qdiscs. However, statistics accounting needs
399 * to account for all, none, or a mix of locked and unlocked child
400 * qdiscs. Percpu stats are added to counters in-band and locking
401 * qdisc totals are added at end.
403 for (ntx = 0; ntx < dev->num_tx_queues; ntx++) {
404 qdisc = netdev_get_tx_queue(dev, ntx)->qdisc_sleeping;
405 spin_lock_bh(qdisc_lock(qdisc));
407 if (qdisc_is_percpu_stats(qdisc)) {
408 __u32 qlen = qdisc_qlen_sum(qdisc);
410 __gnet_stats_copy_basic(NULL, &sch->bstats,
411 qdisc->cpu_bstats,
412 &qdisc->bstats);
413 __gnet_stats_copy_queue(&sch->qstats,
414 qdisc->cpu_qstats,
415 &qdisc->qstats, qlen);
416 } else {
417 sch->q.qlen += qdisc->q.qlen;
418 sch->bstats.bytes += qdisc->bstats.bytes;
419 sch->bstats.packets += qdisc->bstats.packets;
420 sch->qstats.backlog += qdisc->qstats.backlog;
421 sch->qstats.drops += qdisc->qstats.drops;
422 sch->qstats.requeues += qdisc->qstats.requeues;
423 sch->qstats.overlimits += qdisc->qstats.overlimits;
426 spin_unlock_bh(qdisc_lock(qdisc));
429 opt.num_tc = netdev_get_num_tc(dev);
430 memcpy(opt.prio_tc_map, dev->prio_tc_map, sizeof(opt.prio_tc_map));
431 opt.hw = priv->hw_offload;
433 for (tc = 0; tc < netdev_get_num_tc(dev); tc++) {
434 opt.count[tc] = dev->tc_to_txq[tc].count;
435 opt.offset[tc] = dev->tc_to_txq[tc].offset;
438 if (nla_put(skb, TCA_OPTIONS, NLA_ALIGN(sizeof(opt)), &opt))
439 goto nla_put_failure;
441 if ((priv->flags & TC_MQPRIO_F_MODE) &&
442 nla_put_u16(skb, TCA_MQPRIO_MODE, priv->mode))
443 goto nla_put_failure;
445 if ((priv->flags & TC_MQPRIO_F_SHAPER) &&
446 nla_put_u16(skb, TCA_MQPRIO_SHAPER, priv->shaper))
447 goto nla_put_failure;
449 if ((priv->flags & TC_MQPRIO_F_MIN_RATE ||
450 priv->flags & TC_MQPRIO_F_MAX_RATE) &&
451 (dump_rates(priv, &opt, skb) != 0))
452 goto nla_put_failure;
454 return nla_nest_end(skb, nla);
455 nla_put_failure:
456 nlmsg_trim(skb, nla);
457 return -1;
460 static struct Qdisc *mqprio_leaf(struct Qdisc *sch, unsigned long cl)
462 struct netdev_queue *dev_queue = mqprio_queue_get(sch, cl);
464 if (!dev_queue)
465 return NULL;
467 return dev_queue->qdisc_sleeping;
470 static unsigned long mqprio_find(struct Qdisc *sch, u32 classid)
472 struct net_device *dev = qdisc_dev(sch);
473 unsigned int ntx = TC_H_MIN(classid);
475 /* There are essentially two regions here that have valid classid
476 * values. The first region will have a classid value of 1 through
477 * num_tx_queues. All of these are backed by actual Qdiscs.
479 if (ntx < TC_H_MIN_PRIORITY)
480 return (ntx <= dev->num_tx_queues) ? ntx : 0;
482 /* The second region represents the hardware traffic classes. These
483 * are represented by classid values of TC_H_MIN_PRIORITY through
484 * TC_H_MIN_PRIORITY + netdev_get_num_tc - 1
486 return ((ntx - TC_H_MIN_PRIORITY) < netdev_get_num_tc(dev)) ? ntx : 0;
489 static int mqprio_dump_class(struct Qdisc *sch, unsigned long cl,
490 struct sk_buff *skb, struct tcmsg *tcm)
492 if (cl < TC_H_MIN_PRIORITY) {
493 struct netdev_queue *dev_queue = mqprio_queue_get(sch, cl);
494 struct net_device *dev = qdisc_dev(sch);
495 int tc = netdev_txq_to_tc(dev, cl - 1);
497 tcm->tcm_parent = (tc < 0) ? 0 :
498 TC_H_MAKE(TC_H_MAJ(sch->handle),
499 TC_H_MIN(tc + TC_H_MIN_PRIORITY));
500 tcm->tcm_info = dev_queue->qdisc_sleeping->handle;
501 } else {
502 tcm->tcm_parent = TC_H_ROOT;
503 tcm->tcm_info = 0;
505 tcm->tcm_handle |= TC_H_MIN(cl);
506 return 0;
509 static int mqprio_dump_class_stats(struct Qdisc *sch, unsigned long cl,
510 struct gnet_dump *d)
511 __releases(d->lock)
512 __acquires(d->lock)
514 if (cl >= TC_H_MIN_PRIORITY) {
515 int i;
516 __u32 qlen = 0;
517 struct gnet_stats_queue qstats = {0};
518 struct gnet_stats_basic_packed bstats = {0};
519 struct net_device *dev = qdisc_dev(sch);
520 struct netdev_tc_txq tc = dev->tc_to_txq[cl & TC_BITMASK];
522 /* Drop lock here it will be reclaimed before touching
523 * statistics this is required because the d->lock we
524 * hold here is the look on dev_queue->qdisc_sleeping
525 * also acquired below.
527 if (d->lock)
528 spin_unlock_bh(d->lock);
530 for (i = tc.offset; i < tc.offset + tc.count; i++) {
531 struct netdev_queue *q = netdev_get_tx_queue(dev, i);
532 struct Qdisc *qdisc = rtnl_dereference(q->qdisc);
533 struct gnet_stats_basic_cpu __percpu *cpu_bstats = NULL;
534 struct gnet_stats_queue __percpu *cpu_qstats = NULL;
536 spin_lock_bh(qdisc_lock(qdisc));
537 if (qdisc_is_percpu_stats(qdisc)) {
538 cpu_bstats = qdisc->cpu_bstats;
539 cpu_qstats = qdisc->cpu_qstats;
542 qlen = qdisc_qlen_sum(qdisc);
543 __gnet_stats_copy_basic(NULL, &sch->bstats,
544 cpu_bstats, &qdisc->bstats);
545 __gnet_stats_copy_queue(&sch->qstats,
546 cpu_qstats,
547 &qdisc->qstats,
548 qlen);
549 spin_unlock_bh(qdisc_lock(qdisc));
552 /* Reclaim root sleeping lock before completing stats */
553 if (d->lock)
554 spin_lock_bh(d->lock);
555 if (gnet_stats_copy_basic(NULL, d, NULL, &bstats) < 0 ||
556 gnet_stats_copy_queue(d, NULL, &qstats, qlen) < 0)
557 return -1;
558 } else {
559 struct netdev_queue *dev_queue = mqprio_queue_get(sch, cl);
561 sch = dev_queue->qdisc_sleeping;
562 if (gnet_stats_copy_basic(qdisc_root_sleeping_running(sch),
563 d, NULL, &sch->bstats) < 0 ||
564 gnet_stats_copy_queue(d, NULL,
565 &sch->qstats, sch->q.qlen) < 0)
566 return -1;
568 return 0;
571 static void mqprio_walk(struct Qdisc *sch, struct qdisc_walker *arg)
573 struct net_device *dev = qdisc_dev(sch);
574 unsigned long ntx;
576 if (arg->stop)
577 return;
579 /* Walk hierarchy with a virtual class per tc */
580 arg->count = arg->skip;
581 for (ntx = arg->skip; ntx < netdev_get_num_tc(dev); ntx++) {
582 if (arg->fn(sch, ntx + TC_H_MIN_PRIORITY, arg) < 0) {
583 arg->stop = 1;
584 return;
586 arg->count++;
589 /* Pad the values and skip over unused traffic classes */
590 if (ntx < TC_MAX_QUEUE) {
591 arg->count = TC_MAX_QUEUE;
592 ntx = TC_MAX_QUEUE;
595 /* Reset offset, sort out remaining per-queue qdiscs */
596 for (ntx -= TC_MAX_QUEUE; ntx < dev->num_tx_queues; ntx++) {
597 if (arg->fn(sch, ntx + 1, arg) < 0) {
598 arg->stop = 1;
599 return;
601 arg->count++;
605 static struct netdev_queue *mqprio_select_queue(struct Qdisc *sch,
606 struct tcmsg *tcm)
608 return mqprio_queue_get(sch, TC_H_MIN(tcm->tcm_parent));
611 static const struct Qdisc_class_ops mqprio_class_ops = {
612 .graft = mqprio_graft,
613 .leaf = mqprio_leaf,
614 .find = mqprio_find,
615 .walk = mqprio_walk,
616 .dump = mqprio_dump_class,
617 .dump_stats = mqprio_dump_class_stats,
618 .select_queue = mqprio_select_queue,
621 static struct Qdisc_ops mqprio_qdisc_ops __read_mostly = {
622 .cl_ops = &mqprio_class_ops,
623 .id = "mqprio",
624 .priv_size = sizeof(struct mqprio_sched),
625 .init = mqprio_init,
626 .destroy = mqprio_destroy,
627 .attach = mqprio_attach,
628 .dump = mqprio_dump,
629 .owner = THIS_MODULE,
632 static int __init mqprio_module_init(void)
634 return register_qdisc(&mqprio_qdisc_ops);
637 static void __exit mqprio_module_exit(void)
639 unregister_qdisc(&mqprio_qdisc_ops);
642 module_init(mqprio_module_init);
643 module_exit(mqprio_module_exit);
645 MODULE_LICENSE("GPL");