1 // SPDX-License-Identifier: GPL-2.0 2 3 /* net/sched/sch_taprio.c Time Aware Priority Scheduler 4 * 5 * Authors: Vinicius Costa Gomes <vinicius.gomes@intel.com> 6 * 7 */ 8 9 #include <linux/types.h> 10 #include <linux/slab.h> 11 #include <linux/kernel.h> 12 #include <linux/string.h> 13 #include <linux/list.h> 14 #include <linux/errno.h> 15 #include <linux/skbuff.h> 16 #include <linux/module.h> 17 #include <linux/spinlock.h> 18 #include <net/netlink.h> 19 #include <net/pkt_sched.h> 20 #include <net/pkt_cls.h> 21 #include <net/sch_generic.h> 22 23 #define TAPRIO_ALL_GATES_OPEN -1 24 25 struct sched_entry { 26 struct list_head list; 27 28 /* The instant that this entry "closes" and the next one 29 * should open, the qdisc will make some effort so that no 30 * packet leaves after this time. 31 */ 32 ktime_t close_time; 33 atomic_t budget; 34 int index; 35 u32 gate_mask; 36 u32 interval; 37 u8 command; 38 }; 39 40 struct taprio_sched { 41 struct Qdisc **qdiscs; 42 struct Qdisc *root; 43 s64 base_time; 44 int clockid; 45 int picos_per_byte; /* Using picoseconds because for 10Gbps+ 46 * speeds it's sub-nanoseconds per byte 47 */ 48 size_t num_entries; 49 50 /* Protects the update side of the RCU protected current_entry */ 51 spinlock_t current_entry_lock; 52 struct sched_entry __rcu *current_entry; 53 struct list_head entries; 54 ktime_t (*get_time)(void); 55 struct hrtimer advance_timer; 56 }; 57 58 static int taprio_enqueue(struct sk_buff *skb, struct Qdisc *sch, 59 struct sk_buff **to_free) 60 { 61 struct taprio_sched *q = qdisc_priv(sch); 62 struct Qdisc *child; 63 int queue; 64 65 queue = skb_get_queue_mapping(skb); 66 67 child = q->qdiscs[queue]; 68 if (unlikely(!child)) 69 return qdisc_drop(skb, sch, to_free); 70 71 qdisc_qstats_backlog_inc(sch, skb); 72 sch->q.qlen++; 73 74 return qdisc_enqueue(skb, child, to_free); 75 } 76 77 static struct sk_buff *taprio_peek(struct Qdisc *sch) 78 { 79 struct taprio_sched *q = qdisc_priv(sch); 80 struct net_device *dev = qdisc_dev(sch); 81 struct sched_entry *entry; 82 struct sk_buff *skb; 83 u32 gate_mask; 84 int i; 85 86 rcu_read_lock(); 87 entry = rcu_dereference(q->current_entry); 88 gate_mask = entry ? entry->gate_mask : -1; 89 rcu_read_unlock(); 90 91 if (!gate_mask) 92 return NULL; 93 94 for (i = 0; i < dev->num_tx_queues; i++) { 95 struct Qdisc *child = q->qdiscs[i]; 96 int prio; 97 u8 tc; 98 99 if (unlikely(!child)) 100 continue; 101 102 skb = child->ops->peek(child); 103 if (!skb) 104 continue; 105 106 prio = skb->priority; 107 tc = netdev_get_prio_tc_map(dev, prio); 108 109 if (!(gate_mask & BIT(tc))) 110 return NULL; 111 112 return skb; 113 } 114 115 return NULL; 116 } 117 118 static inline int length_to_duration(struct taprio_sched *q, int len) 119 { 120 return (len * q->picos_per_byte) / 1000; 121 } 122 123 static struct sk_buff *taprio_dequeue(struct Qdisc *sch) 124 { 125 struct taprio_sched *q = qdisc_priv(sch); 126 struct net_device *dev = qdisc_dev(sch); 127 struct sched_entry *entry; 128 struct sk_buff *skb; 129 u32 gate_mask; 130 int i; 131 132 rcu_read_lock(); 133 entry = rcu_dereference(q->current_entry); 134 /* if there's no entry, it means that the schedule didn't 135 * start yet, so force all gates to be open, this is in 136 * accordance to IEEE 802.1Qbv-2015 Section 8.6.9.4.5 137 * "AdminGateSates" 138 */ 139 gate_mask = entry ? entry->gate_mask : TAPRIO_ALL_GATES_OPEN; 140 rcu_read_unlock(); 141 142 if (!gate_mask) 143 return NULL; 144 145 for (i = 0; i < dev->num_tx_queues; i++) { 146 struct Qdisc *child = q->qdiscs[i]; 147 ktime_t guard; 148 int prio; 149 int len; 150 u8 tc; 151 152 if (unlikely(!child)) 153 continue; 154 155 skb = child->ops->peek(child); 156 if (!skb) 157 continue; 158 159 prio = skb->priority; 160 tc = netdev_get_prio_tc_map(dev, prio); 161 162 if (!(gate_mask & BIT(tc))) 163 continue; 164 165 len = qdisc_pkt_len(skb); 166 guard = ktime_add_ns(q->get_time(), 167 length_to_duration(q, len)); 168 169 /* In the case that there's no gate entry, there's no 170 * guard band ... 171 */ 172 if (gate_mask != TAPRIO_ALL_GATES_OPEN && 173 ktime_after(guard, entry->close_time)) 174 return NULL; 175 176 /* ... and no budget. */ 177 if (gate_mask != TAPRIO_ALL_GATES_OPEN && 178 atomic_sub_return(len, &entry->budget) < 0) 179 return NULL; 180 181 skb = child->ops->dequeue(child); 182 if (unlikely(!skb)) 183 return NULL; 184 185 qdisc_bstats_update(sch, skb); 186 qdisc_qstats_backlog_dec(sch, skb); 187 sch->q.qlen--; 188 189 return skb; 190 } 191 192 return NULL; 193 } 194 195 static bool should_restart_cycle(const struct taprio_sched *q, 196 const struct sched_entry *entry) 197 { 198 WARN_ON(!entry); 199 200 return list_is_last(&entry->list, &q->entries); 201 } 202 203 static enum hrtimer_restart advance_sched(struct hrtimer *timer) 204 { 205 struct taprio_sched *q = container_of(timer, struct taprio_sched, 206 advance_timer); 207 struct sched_entry *entry, *next; 208 struct Qdisc *sch = q->root; 209 ktime_t close_time; 210 211 spin_lock(&q->current_entry_lock); 212 entry = rcu_dereference_protected(q->current_entry, 213 lockdep_is_held(&q->current_entry_lock)); 214 215 /* This is the case that it's the first time that the schedule 216 * runs, so it only happens once per schedule. The first entry 217 * is pre-calculated during the schedule initialization. 218 */ 219 if (unlikely(!entry)) { 220 next = list_first_entry(&q->entries, struct sched_entry, 221 list); 222 close_time = next->close_time; 223 goto first_run; 224 } 225 226 if (should_restart_cycle(q, entry)) 227 next = list_first_entry(&q->entries, struct sched_entry, 228 list); 229 else 230 next = list_next_entry(entry, list); 231 232 close_time = ktime_add_ns(entry->close_time, next->interval); 233 234 next->close_time = close_time; 235 atomic_set(&next->budget, 236 (next->interval * 1000) / q->picos_per_byte); 237 238 first_run: 239 rcu_assign_pointer(q->current_entry, next); 240 spin_unlock(&q->current_entry_lock); 241 242 hrtimer_set_expires(&q->advance_timer, close_time); 243 244 rcu_read_lock(); 245 __netif_schedule(sch); 246 rcu_read_unlock(); 247 248 return HRTIMER_RESTART; 249 } 250 251 static const struct nla_policy entry_policy[TCA_TAPRIO_SCHED_ENTRY_MAX + 1] = { 252 [TCA_TAPRIO_SCHED_ENTRY_INDEX] = { .type = NLA_U32 }, 253 [TCA_TAPRIO_SCHED_ENTRY_CMD] = { .type = NLA_U8 }, 254 [TCA_TAPRIO_SCHED_ENTRY_GATE_MASK] = { .type = NLA_U32 }, 255 [TCA_TAPRIO_SCHED_ENTRY_INTERVAL] = { .type = NLA_U32 }, 256 }; 257 258 static const struct nla_policy entry_list_policy[TCA_TAPRIO_SCHED_MAX + 1] = { 259 [TCA_TAPRIO_SCHED_ENTRY] = { .type = NLA_NESTED }, 260 }; 261 262 static const struct nla_policy taprio_policy[TCA_TAPRIO_ATTR_MAX + 1] = { 263 [TCA_TAPRIO_ATTR_PRIOMAP] = { 264 .len = sizeof(struct tc_mqprio_qopt) 265 }, 266 [TCA_TAPRIO_ATTR_SCHED_ENTRY_LIST] = { .type = NLA_NESTED }, 267 [TCA_TAPRIO_ATTR_SCHED_BASE_TIME] = { .type = NLA_S64 }, 268 [TCA_TAPRIO_ATTR_SCHED_SINGLE_ENTRY] = { .type = NLA_NESTED }, 269 [TCA_TAPRIO_ATTR_SCHED_CLOCKID] = { .type = NLA_S32 }, 270 }; 271 272 static int fill_sched_entry(struct nlattr **tb, struct sched_entry *entry, 273 struct netlink_ext_ack *extack) 274 { 275 u32 interval = 0; 276 277 if (tb[TCA_TAPRIO_SCHED_ENTRY_CMD]) 278 entry->command = nla_get_u8( 279 tb[TCA_TAPRIO_SCHED_ENTRY_CMD]); 280 281 if (tb[TCA_TAPRIO_SCHED_ENTRY_GATE_MASK]) 282 entry->gate_mask = nla_get_u32( 283 tb[TCA_TAPRIO_SCHED_ENTRY_GATE_MASK]); 284 285 if (tb[TCA_TAPRIO_SCHED_ENTRY_INTERVAL]) 286 interval = nla_get_u32( 287 tb[TCA_TAPRIO_SCHED_ENTRY_INTERVAL]); 288 289 if (interval == 0) { 290 NL_SET_ERR_MSG(extack, "Invalid interval for schedule entry"); 291 return -EINVAL; 292 } 293 294 entry->interval = interval; 295 296 return 0; 297 } 298 299 static int parse_sched_entry(struct nlattr *n, struct sched_entry *entry, 300 int index, struct netlink_ext_ack *extack) 301 { 302 struct nlattr *tb[TCA_TAPRIO_SCHED_ENTRY_MAX + 1] = { }; 303 int err; 304 305 err = nla_parse_nested(tb, TCA_TAPRIO_SCHED_ENTRY_MAX, n, 306 entry_policy, NULL); 307 if (err < 0) { 308 NL_SET_ERR_MSG(extack, "Could not parse nested entry"); 309 return -EINVAL; 310 } 311 312 entry->index = index; 313 314 return fill_sched_entry(tb, entry, extack); 315 } 316 317 /* Returns the number of entries in case of success */ 318 static int parse_sched_single_entry(struct nlattr *n, 319 struct taprio_sched *q, 320 struct netlink_ext_ack *extack) 321 { 322 struct nlattr *tb_entry[TCA_TAPRIO_SCHED_ENTRY_MAX + 1] = { }; 323 struct nlattr *tb_list[TCA_TAPRIO_SCHED_MAX + 1] = { }; 324 struct sched_entry *entry; 325 bool found = false; 326 u32 index; 327 int err; 328 329 err = nla_parse_nested(tb_list, TCA_TAPRIO_SCHED_MAX, 330 n, entry_list_policy, NULL); 331 if (err < 0) { 332 NL_SET_ERR_MSG(extack, "Could not parse nested entry"); 333 return -EINVAL; 334 } 335 336 if (!tb_list[TCA_TAPRIO_SCHED_ENTRY]) { 337 NL_SET_ERR_MSG(extack, "Single-entry must include an entry"); 338 return -EINVAL; 339 } 340 341 err = nla_parse_nested(tb_entry, TCA_TAPRIO_SCHED_ENTRY_MAX, 342 tb_list[TCA_TAPRIO_SCHED_ENTRY], 343 entry_policy, NULL); 344 if (err < 0) { 345 NL_SET_ERR_MSG(extack, "Could not parse nested entry"); 346 return -EINVAL; 347 } 348 349 if (!tb_entry[TCA_TAPRIO_SCHED_ENTRY_INDEX]) { 350 NL_SET_ERR_MSG(extack, "Entry must specify an index\n"); 351 return -EINVAL; 352 } 353 354 index = nla_get_u32(tb_entry[TCA_TAPRIO_SCHED_ENTRY_INDEX]); 355 if (index >= q->num_entries) { 356 NL_SET_ERR_MSG(extack, "Index for single entry exceeds number of entries in schedule"); 357 return -EINVAL; 358 } 359 360 list_for_each_entry(entry, &q->entries, list) { 361 if (entry->index == index) { 362 found = true; 363 break; 364 } 365 } 366 367 if (!found) { 368 NL_SET_ERR_MSG(extack, "Could not find entry"); 369 return -ENOENT; 370 } 371 372 err = fill_sched_entry(tb_entry, entry, extack); 373 if (err < 0) 374 return err; 375 376 return q->num_entries; 377 } 378 379 static int parse_sched_list(struct nlattr *list, 380 struct taprio_sched *q, 381 struct netlink_ext_ack *extack) 382 { 383 struct nlattr *n; 384 int err, rem; 385 int i = 0; 386 387 if (!list) 388 return -EINVAL; 389 390 nla_for_each_nested(n, list, rem) { 391 struct sched_entry *entry; 392 393 if (nla_type(n) != TCA_TAPRIO_SCHED_ENTRY) { 394 NL_SET_ERR_MSG(extack, "Attribute is not of type 'entry'"); 395 continue; 396 } 397 398 entry = kzalloc(sizeof(*entry), GFP_KERNEL); 399 if (!entry) { 400 NL_SET_ERR_MSG(extack, "Not enough memory for entry"); 401 return -ENOMEM; 402 } 403 404 err = parse_sched_entry(n, entry, i, extack); 405 if (err < 0) { 406 kfree(entry); 407 return err; 408 } 409 410 list_add_tail(&entry->list, &q->entries); 411 i++; 412 } 413 414 q->num_entries = i; 415 416 return i; 417 } 418 419 /* Returns the number of entries in case of success */ 420 static int parse_taprio_opt(struct nlattr **tb, struct taprio_sched *q, 421 struct netlink_ext_ack *extack) 422 { 423 int err = 0; 424 int clockid; 425 426 if (tb[TCA_TAPRIO_ATTR_SCHED_ENTRY_LIST] && 427 tb[TCA_TAPRIO_ATTR_SCHED_SINGLE_ENTRY]) 428 return -EINVAL; 429 430 if (tb[TCA_TAPRIO_ATTR_SCHED_SINGLE_ENTRY] && q->num_entries == 0) 431 return -EINVAL; 432 433 if (q->clockid == -1 && !tb[TCA_TAPRIO_ATTR_SCHED_CLOCKID]) 434 return -EINVAL; 435 436 if (tb[TCA_TAPRIO_ATTR_SCHED_BASE_TIME]) 437 q->base_time = nla_get_s64( 438 tb[TCA_TAPRIO_ATTR_SCHED_BASE_TIME]); 439 440 if (tb[TCA_TAPRIO_ATTR_SCHED_CLOCKID]) { 441 clockid = nla_get_s32(tb[TCA_TAPRIO_ATTR_SCHED_CLOCKID]); 442 443 /* We only support static clockids and we don't allow 444 * for it to be modified after the first init. 445 */ 446 if (clockid < 0 || (q->clockid != -1 && q->clockid != clockid)) 447 return -EINVAL; 448 449 q->clockid = clockid; 450 } 451 452 if (tb[TCA_TAPRIO_ATTR_SCHED_ENTRY_LIST]) 453 err = parse_sched_list( 454 tb[TCA_TAPRIO_ATTR_SCHED_ENTRY_LIST], q, extack); 455 else if (tb[TCA_TAPRIO_ATTR_SCHED_SINGLE_ENTRY]) 456 err = parse_sched_single_entry( 457 tb[TCA_TAPRIO_ATTR_SCHED_SINGLE_ENTRY], q, extack); 458 459 /* parse_sched_* return the number of entries in the schedule, 460 * a schedule with zero entries is an error. 461 */ 462 if (err == 0) { 463 NL_SET_ERR_MSG(extack, "The schedule should contain at least one entry"); 464 return -EINVAL; 465 } 466 467 return err; 468 } 469 470 static int taprio_parse_mqprio_opt(struct net_device *dev, 471 struct tc_mqprio_qopt *qopt, 472 struct netlink_ext_ack *extack) 473 { 474 int i, j; 475 476 if (!qopt) { 477 NL_SET_ERR_MSG(extack, "'mqprio' configuration is necessary"); 478 return -EINVAL; 479 } 480 481 /* Verify num_tc is not out of max range */ 482 if (qopt->num_tc > TC_MAX_QUEUE) { 483 NL_SET_ERR_MSG(extack, "Number of traffic classes is outside valid range"); 484 return -EINVAL; 485 } 486 487 /* taprio imposes that traffic classes map 1:n to tx queues */ 488 if (qopt->num_tc > dev->num_tx_queues) { 489 NL_SET_ERR_MSG(extack, "Number of traffic classes is greater than number of HW queues"); 490 return -EINVAL; 491 } 492 493 /* Verify priority mapping uses valid tcs */ 494 for (i = 0; i < TC_BITMASK + 1; i++) { 495 if (qopt->prio_tc_map[i] >= qopt->num_tc) { 496 NL_SET_ERR_MSG(extack, "Invalid traffic class in priority to traffic class mapping"); 497 return -EINVAL; 498 } 499 } 500 501 for (i = 0; i < qopt->num_tc; i++) { 502 unsigned int last = qopt->offset[i] + qopt->count[i]; 503 504 /* Verify the queue count is in tx range being equal to the 505 * real_num_tx_queues indicates the last queue is in use. 506 */ 507 if (qopt->offset[i] >= dev->num_tx_queues || 508 !qopt->count[i] || 509 last > dev->real_num_tx_queues) { 510 NL_SET_ERR_MSG(extack, "Invalid queue in traffic class to queue mapping"); 511 return -EINVAL; 512 } 513 514 /* Verify that the offset and counts do not overlap */ 515 for (j = i + 1; j < qopt->num_tc; j++) { 516 if (last > qopt->offset[j]) { 517 NL_SET_ERR_MSG(extack, "Detected overlap in the traffic class to queue mapping"); 518 return -EINVAL; 519 } 520 } 521 } 522 523 return 0; 524 } 525 526 static ktime_t taprio_get_start_time(struct Qdisc *sch) 527 { 528 struct taprio_sched *q = qdisc_priv(sch); 529 struct sched_entry *entry; 530 ktime_t now, base, cycle; 531 s64 n; 532 533 base = ns_to_ktime(q->base_time); 534 cycle = 0; 535 536 /* Calculate the cycle_time, by summing all the intervals. 537 */ 538 list_for_each_entry(entry, &q->entries, list) 539 cycle = ktime_add_ns(cycle, entry->interval); 540 541 if (!cycle) 542 return base; 543 544 now = q->get_time(); 545 546 if (ktime_after(base, now)) 547 return base; 548 549 /* Schedule the start time for the beginning of the next 550 * cycle. 551 */ 552 n = div64_s64(ktime_sub_ns(now, base), cycle); 553 554 return ktime_add_ns(base, (n + 1) * cycle); 555 } 556 557 static void taprio_start_sched(struct Qdisc *sch, ktime_t start) 558 { 559 struct taprio_sched *q = qdisc_priv(sch); 560 struct sched_entry *first; 561 unsigned long flags; 562 563 spin_lock_irqsave(&q->current_entry_lock, flags); 564 565 first = list_first_entry(&q->entries, struct sched_entry, 566 list); 567 568 first->close_time = ktime_add_ns(start, first->interval); 569 atomic_set(&first->budget, 570 (first->interval * 1000) / q->picos_per_byte); 571 rcu_assign_pointer(q->current_entry, NULL); 572 573 spin_unlock_irqrestore(&q->current_entry_lock, flags); 574 575 hrtimer_start(&q->advance_timer, start, HRTIMER_MODE_ABS); 576 } 577 578 static int taprio_change(struct Qdisc *sch, struct nlattr *opt, 579 struct netlink_ext_ack *extack) 580 { 581 struct nlattr *tb[TCA_TAPRIO_ATTR_MAX + 1] = { }; 582 struct taprio_sched *q = qdisc_priv(sch); 583 struct net_device *dev = qdisc_dev(sch); 584 struct tc_mqprio_qopt *mqprio = NULL; 585 struct ethtool_link_ksettings ecmd; 586 int i, err, size; 587 s64 link_speed; 588 ktime_t start; 589 590 err = nla_parse_nested(tb, TCA_TAPRIO_ATTR_MAX, opt, 591 taprio_policy, extack); 592 if (err < 0) 593 return err; 594 595 err = -EINVAL; 596 if (tb[TCA_TAPRIO_ATTR_PRIOMAP]) 597 mqprio = nla_data(tb[TCA_TAPRIO_ATTR_PRIOMAP]); 598 599 err = taprio_parse_mqprio_opt(dev, mqprio, extack); 600 if (err < 0) 601 return err; 602 603 /* A schedule with less than one entry is an error */ 604 size = parse_taprio_opt(tb, q, extack); 605 if (size < 0) 606 return size; 607 608 hrtimer_init(&q->advance_timer, q->clockid, HRTIMER_MODE_ABS); 609 q->advance_timer.function = advance_sched; 610 611 switch (q->clockid) { 612 case CLOCK_REALTIME: 613 q->get_time = ktime_get_real; 614 break; 615 case CLOCK_MONOTONIC: 616 q->get_time = ktime_get; 617 break; 618 case CLOCK_BOOTTIME: 619 q->get_time = ktime_get_boottime; 620 break; 621 case CLOCK_TAI: 622 q->get_time = ktime_get_clocktai; 623 break; 624 default: 625 return -ENOTSUPP; 626 } 627 628 for (i = 0; i < dev->num_tx_queues; i++) { 629 struct netdev_queue *dev_queue; 630 struct Qdisc *qdisc; 631 632 dev_queue = netdev_get_tx_queue(dev, i); 633 qdisc = qdisc_create_dflt(dev_queue, 634 &pfifo_qdisc_ops, 635 TC_H_MAKE(TC_H_MAJ(sch->handle), 636 TC_H_MIN(i + 1)), 637 extack); 638 if (!qdisc) 639 return -ENOMEM; 640 641 if (i < dev->real_num_tx_queues) 642 qdisc_hash_add(qdisc, false); 643 644 q->qdiscs[i] = qdisc; 645 } 646 647 if (mqprio) { 648 netdev_set_num_tc(dev, mqprio->num_tc); 649 for (i = 0; i < mqprio->num_tc; i++) 650 netdev_set_tc_queue(dev, i, 651 mqprio->count[i], 652 mqprio->offset[i]); 653 654 /* Always use supplied priority mappings */ 655 for (i = 0; i < TC_BITMASK + 1; i++) 656 netdev_set_prio_tc_map(dev, i, 657 mqprio->prio_tc_map[i]); 658 } 659 660 if (!__ethtool_get_link_ksettings(dev, &ecmd)) 661 link_speed = ecmd.base.speed; 662 else 663 link_speed = SPEED_1000; 664 665 q->picos_per_byte = div64_s64(NSEC_PER_SEC * 1000LL * 8, 666 link_speed * 1000 * 1000); 667 668 start = taprio_get_start_time(sch); 669 if (!start) 670 return 0; 671 672 taprio_start_sched(sch, start); 673 674 return 0; 675 } 676 677 static void taprio_destroy(struct Qdisc *sch) 678 { 679 struct taprio_sched *q = qdisc_priv(sch); 680 struct net_device *dev = qdisc_dev(sch); 681 struct sched_entry *entry, *n; 682 unsigned int i; 683 684 hrtimer_cancel(&q->advance_timer); 685 686 if (q->qdiscs) { 687 for (i = 0; i < dev->num_tx_queues && q->qdiscs[i]; i++) 688 qdisc_put(q->qdiscs[i]); 689 690 kfree(q->qdiscs); 691 } 692 q->qdiscs = NULL; 693 694 netdev_set_num_tc(dev, 0); 695 696 list_for_each_entry_safe(entry, n, &q->entries, list) { 697 list_del(&entry->list); 698 kfree(entry); 699 } 700 } 701 702 static int taprio_init(struct Qdisc *sch, struct nlattr *opt, 703 struct netlink_ext_ack *extack) 704 { 705 struct taprio_sched *q = qdisc_priv(sch); 706 struct net_device *dev = qdisc_dev(sch); 707 708 INIT_LIST_HEAD(&q->entries); 709 spin_lock_init(&q->current_entry_lock); 710 711 /* We may overwrite the configuration later */ 712 hrtimer_init(&q->advance_timer, CLOCK_TAI, HRTIMER_MODE_ABS); 713 714 q->root = sch; 715 716 /* We only support static clockids. Use an invalid value as default 717 * and get the valid one on taprio_change(). 718 */ 719 q->clockid = -1; 720 721 if (sch->parent != TC_H_ROOT) 722 return -EOPNOTSUPP; 723 724 if (!netif_is_multiqueue(dev)) 725 return -EOPNOTSUPP; 726 727 /* pre-allocate qdisc, attachment can't fail */ 728 q->qdiscs = kcalloc(dev->num_tx_queues, 729 sizeof(q->qdiscs[0]), 730 GFP_KERNEL); 731 732 if (!q->qdiscs) 733 return -ENOMEM; 734 735 if (!opt) 736 return -EINVAL; 737 738 return taprio_change(sch, opt, extack); 739 } 740 741 static struct netdev_queue *taprio_queue_get(struct Qdisc *sch, 742 unsigned long cl) 743 { 744 struct net_device *dev = qdisc_dev(sch); 745 unsigned long ntx = cl - 1; 746 747 if (ntx >= dev->num_tx_queues) 748 return NULL; 749 750 return netdev_get_tx_queue(dev, ntx); 751 } 752 753 static int taprio_graft(struct Qdisc *sch, unsigned long cl, 754 struct Qdisc *new, struct Qdisc **old, 755 struct netlink_ext_ack *extack) 756 { 757 struct taprio_sched *q = qdisc_priv(sch); 758 struct net_device *dev = qdisc_dev(sch); 759 struct netdev_queue *dev_queue = taprio_queue_get(sch, cl); 760 761 if (!dev_queue) 762 return -EINVAL; 763 764 if (dev->flags & IFF_UP) 765 dev_deactivate(dev); 766 767 *old = q->qdiscs[cl - 1]; 768 q->qdiscs[cl - 1] = new; 769 770 if (new) 771 new->flags |= TCQ_F_ONETXQUEUE | TCQ_F_NOPARENT; 772 773 if (dev->flags & IFF_UP) 774 dev_activate(dev); 775 776 return 0; 777 } 778 779 static int dump_entry(struct sk_buff *msg, 780 const struct sched_entry *entry) 781 { 782 struct nlattr *item; 783 784 item = nla_nest_start(msg, TCA_TAPRIO_SCHED_ENTRY); 785 if (!item) 786 return -ENOSPC; 787 788 if (nla_put_u32(msg, TCA_TAPRIO_SCHED_ENTRY_INDEX, entry->index)) 789 goto nla_put_failure; 790 791 if (nla_put_u8(msg, TCA_TAPRIO_SCHED_ENTRY_CMD, entry->command)) 792 goto nla_put_failure; 793 794 if (nla_put_u32(msg, TCA_TAPRIO_SCHED_ENTRY_GATE_MASK, 795 entry->gate_mask)) 796 goto nla_put_failure; 797 798 if (nla_put_u32(msg, TCA_TAPRIO_SCHED_ENTRY_INTERVAL, 799 entry->interval)) 800 goto nla_put_failure; 801 802 return nla_nest_end(msg, item); 803 804 nla_put_failure: 805 nla_nest_cancel(msg, item); 806 return -1; 807 } 808 809 static int taprio_dump(struct Qdisc *sch, struct sk_buff *skb) 810 { 811 struct taprio_sched *q = qdisc_priv(sch); 812 struct net_device *dev = qdisc_dev(sch); 813 struct tc_mqprio_qopt opt = { 0 }; 814 struct nlattr *nest, *entry_list; 815 struct sched_entry *entry; 816 unsigned int i; 817 818 opt.num_tc = netdev_get_num_tc(dev); 819 memcpy(opt.prio_tc_map, dev->prio_tc_map, sizeof(opt.prio_tc_map)); 820 821 for (i = 0; i < netdev_get_num_tc(dev); i++) { 822 opt.count[i] = dev->tc_to_txq[i].count; 823 opt.offset[i] = dev->tc_to_txq[i].offset; 824 } 825 826 nest = nla_nest_start(skb, TCA_OPTIONS); 827 if (!nest) 828 return -ENOSPC; 829 830 if (nla_put(skb, TCA_TAPRIO_ATTR_PRIOMAP, sizeof(opt), &opt)) 831 goto options_error; 832 833 if (nla_put_s64(skb, TCA_TAPRIO_ATTR_SCHED_BASE_TIME, 834 q->base_time, TCA_TAPRIO_PAD)) 835 goto options_error; 836 837 if (nla_put_s32(skb, TCA_TAPRIO_ATTR_SCHED_CLOCKID, q->clockid)) 838 goto options_error; 839 840 entry_list = nla_nest_start(skb, TCA_TAPRIO_ATTR_SCHED_ENTRY_LIST); 841 if (!entry_list) 842 goto options_error; 843 844 list_for_each_entry(entry, &q->entries, list) { 845 if (dump_entry(skb, entry) < 0) 846 goto options_error; 847 } 848 849 nla_nest_end(skb, entry_list); 850 851 return nla_nest_end(skb, nest); 852 853 options_error: 854 nla_nest_cancel(skb, nest); 855 return -1; 856 } 857 858 static struct Qdisc *taprio_leaf(struct Qdisc *sch, unsigned long cl) 859 { 860 struct netdev_queue *dev_queue = taprio_queue_get(sch, cl); 861 862 if (!dev_queue) 863 return NULL; 864 865 return dev_queue->qdisc_sleeping; 866 } 867 868 static unsigned long taprio_find(struct Qdisc *sch, u32 classid) 869 { 870 unsigned int ntx = TC_H_MIN(classid); 871 872 if (!taprio_queue_get(sch, ntx)) 873 return 0; 874 return ntx; 875 } 876 877 static int taprio_dump_class(struct Qdisc *sch, unsigned long cl, 878 struct sk_buff *skb, struct tcmsg *tcm) 879 { 880 struct netdev_queue *dev_queue = taprio_queue_get(sch, cl); 881 882 tcm->tcm_parent = TC_H_ROOT; 883 tcm->tcm_handle |= TC_H_MIN(cl); 884 tcm->tcm_info = dev_queue->qdisc_sleeping->handle; 885 886 return 0; 887 } 888 889 static int taprio_dump_class_stats(struct Qdisc *sch, unsigned long cl, 890 struct gnet_dump *d) 891 __releases(d->lock) 892 __acquires(d->lock) 893 { 894 struct netdev_queue *dev_queue = taprio_queue_get(sch, cl); 895 896 sch = dev_queue->qdisc_sleeping; 897 if (gnet_stats_copy_basic(&sch->running, d, NULL, &sch->bstats) < 0 || 898 gnet_stats_copy_queue(d, NULL, &sch->qstats, sch->q.qlen) < 0) 899 return -1; 900 return 0; 901 } 902 903 static void taprio_walk(struct Qdisc *sch, struct qdisc_walker *arg) 904 { 905 struct net_device *dev = qdisc_dev(sch); 906 unsigned long ntx; 907 908 if (arg->stop) 909 return; 910 911 arg->count = arg->skip; 912 for (ntx = arg->skip; ntx < dev->num_tx_queues; ntx++) { 913 if (arg->fn(sch, ntx + 1, arg) < 0) { 914 arg->stop = 1; 915 break; 916 } 917 arg->count++; 918 } 919 } 920 921 static struct netdev_queue *taprio_select_queue(struct Qdisc *sch, 922 struct tcmsg *tcm) 923 { 924 return taprio_queue_get(sch, TC_H_MIN(tcm->tcm_parent)); 925 } 926 927 static const struct Qdisc_class_ops taprio_class_ops = { 928 .graft = taprio_graft, 929 .leaf = taprio_leaf, 930 .find = taprio_find, 931 .walk = taprio_walk, 932 .dump = taprio_dump_class, 933 .dump_stats = taprio_dump_class_stats, 934 .select_queue = taprio_select_queue, 935 }; 936 937 static struct Qdisc_ops taprio_qdisc_ops __read_mostly = { 938 .cl_ops = &taprio_class_ops, 939 .id = "taprio", 940 .priv_size = sizeof(struct taprio_sched), 941 .init = taprio_init, 942 .destroy = taprio_destroy, 943 .peek = taprio_peek, 944 .dequeue = taprio_dequeue, 945 .enqueue = taprio_enqueue, 946 .dump = taprio_dump, 947 .owner = THIS_MODULE, 948 }; 949 950 static int __init taprio_module_init(void) 951 { 952 return register_qdisc(&taprio_qdisc_ops); 953 } 954 955 static void __exit taprio_module_exit(void) 956 { 957 unregister_qdisc(&taprio_qdisc_ops); 958 } 959 960 module_init(taprio_module_init); 961 module_exit(taprio_module_exit); 962 MODULE_LICENSE("GPL"); 963