1// SPDX-License-Identifier: GPL-2.0-or-later 2/* 3 * net/sched/sch_htb.c Hierarchical token bucket, feed tree version 4 * 5 * Authors: Martin Devera, <devik@cdi.cz> 6 * 7 * Credits (in time order) for older HTB versions: 8 * Stef Coene <stef.coene@docum.org> 9 * HTB support at LARTC mailing list 10 * Ondrej Kraus, <krauso@barr.cz> 11 * found missing INIT_QDISC(htb) 12 * Vladimir Smelhaus, Aamer Akhter, Bert Hubert 13 * helped a lot to locate nasty class stall bug 14 * Andi Kleen, Jamal Hadi, Bert Hubert 15 * code review and helpful comments on shaping 16 * Tomasz Wrona, <tw@eter.tym.pl> 17 * created test case so that I was able to fix nasty bug 18 * Wilfried Weissmann 19 * spotted bug in dequeue code and helped with fix 20 * Jiri Fojtasek 21 * fixed requeue routine 22 * and many others. thanks. 23 */ 24#include <linux/module.h> 25#include <linux/moduleparam.h> 26#include <linux/types.h> 27#include <linux/kernel.h> 28#include <linux/string.h> 29#include <linux/errno.h> 30#include <linux/skbuff.h> 31#include <linux/list.h> 32#include <linux/compiler.h> 33#include <linux/rbtree.h> 34#include <linux/workqueue.h> 35#include <linux/slab.h> 36#include <net/netlink.h> 37#include <net/sch_generic.h> 38#include <net/pkt_sched.h> 39#include <net/pkt_cls.h> 40 41/* HTB algorithm. 42 Author: devik@cdi.cz 43 ======================================================================== 44 HTB is like TBF with multiple classes. It is also similar to CBQ because 45 it allows to assign priority to each class in hierarchy. 46 In fact it is another implementation of Floyd's formal sharing. 47 48 Levels: 49 Each class is assigned level. Leaf has ALWAYS level 0 and root 50 classes have level TC_HTB_MAXDEPTH-1. Interior nodes has level 51 one less than their parent. 52*/ 53 54static int htb_hysteresis __read_mostly = 0; /* whether to use mode hysteresis for speedup */ 55#define HTB_VER 0x30011 /* major must be matched with number supplied by TC as version */ 56 57#if HTB_VER >> 16 != TC_HTB_PROTOVER 58#error "Mismatched sch_htb.c and pkt_sch.h" 59#endif 60 61/* Module parameter and sysfs export */ 62module_param (htb_hysteresis, int, 0640); 63MODULE_PARM_DESC(htb_hysteresis, "Hysteresis mode, less CPU load, less accurate"); 64 65static int htb_rate_est = 0; /* htb classes have a default rate estimator */ 66module_param(htb_rate_est, int, 0640); 67MODULE_PARM_DESC(htb_rate_est, "setup a default rate estimator (4sec 16sec) for htb classes"); 68 69/* used internaly to keep status of single class */ 70enum htb_cmode { 71 HTB_CANT_SEND, /* class can't send and can't borrow */ 72 HTB_MAY_BORROW, /* class can't send but may borrow */ 73 HTB_CAN_SEND /* class can send */ 74}; 75 76struct htb_prio { 77 union { 78 struct rb_root row; 79 struct rb_root feed; 80 }; 81 struct rb_node *ptr; 82 /* When class changes from state 1->2 and disconnects from 83 * parent's feed then we lost ptr value and start from the 84 * first child again. Here we store classid of the 85 * last valid ptr (used when ptr is NULL). 86 */ 87 u32 last_ptr_id; 88}; 89 90/* interior & leaf nodes; props specific to leaves are marked L: 91 * To reduce false sharing, place mostly read fields at beginning, 92 * and mostly written ones at the end. 93 */ 94struct htb_class { 95 struct Qdisc_class_common common; 96 struct psched_ratecfg rate; 97 struct psched_ratecfg ceil; 98 s64 buffer, cbuffer;/* token bucket depth/rate */ 99 s64 mbuffer; /* max wait time */ 100 u32 prio; /* these two are used only by leaves... */ 101 int quantum; /* but stored for parent-to-leaf return */ 102 103 struct tcf_proto __rcu *filter_list; /* class attached filters */ 104 struct tcf_block *block; 105 106 int level; /* our level (see above) */ 107 unsigned int children; 108 struct htb_class *parent; /* parent class */ 109 110 struct net_rate_estimator __rcu *rate_est; 111 112 /* 113 * Written often fields 114 */ 115 struct gnet_stats_basic_sync bstats; 116 struct gnet_stats_basic_sync bstats_bias; 117 struct tc_htb_xstats xstats; /* our special stats */ 118 119 /* token bucket parameters */ 120 s64 tokens, ctokens;/* current number of tokens */ 121 s64 t_c; /* checkpoint time */ 122 123 union { 124 struct htb_class_leaf { 125 int deficit[TC_HTB_MAXDEPTH]; 126 struct Qdisc *q; 127 struct netdev_queue *offload_queue; 128 } leaf; 129 struct htb_class_inner { 130 struct htb_prio clprio[TC_HTB_NUMPRIO]; 131 } inner; 132 }; 133 s64 pq_key; 134 135 int prio_activity; /* for which prios are we active */ 136 enum htb_cmode cmode; /* current mode of the class */ 137 struct rb_node pq_node; /* node for event queue */ 138 struct rb_node node[TC_HTB_NUMPRIO]; /* node for self or feed tree */ 139 140 unsigned int drops ____cacheline_aligned_in_smp; 141 unsigned int overlimits; 142}; 143 144struct htb_level { 145 struct rb_root wait_pq; 146 struct htb_prio hprio[TC_HTB_NUMPRIO]; 147}; 148 149struct htb_sched { 150 struct Qdisc_class_hash clhash; 151 int defcls; /* class where unclassified flows go to */ 152 int rate2quantum; /* quant = rate / rate2quantum */ 153 154 /* filters for qdisc itself */ 155 struct tcf_proto __rcu *filter_list; 156 struct tcf_block *block; 157 158#define HTB_WARN_TOOMANYEVENTS 0x1 159 unsigned int warned; /* only one warning */ 160 int direct_qlen; 161 struct work_struct work; 162 163 /* non shaped skbs; let them go directly thru */ 164 struct qdisc_skb_head direct_queue; 165 u32 direct_pkts; 166 u32 overlimits; 167 168 struct qdisc_watchdog watchdog; 169 170 s64 now; /* cached dequeue time */ 171 172 /* time of nearest event per level (row) */ 173 s64 near_ev_cache[TC_HTB_MAXDEPTH]; 174 175 int row_mask[TC_HTB_MAXDEPTH]; 176 177 struct htb_level hlevel[TC_HTB_MAXDEPTH]; 178 179 struct Qdisc **direct_qdiscs; 180 unsigned int num_direct_qdiscs; 181 182 bool offload; 183}; 184 185/* find class in global hash table using given handle */ 186static inline struct htb_class *htb_find(u32 handle, struct Qdisc *sch) 187{ 188 struct htb_sched *q = qdisc_priv(sch); 189 struct Qdisc_class_common *clc; 190 191 clc = qdisc_class_find(&q->clhash, handle); 192 if (clc == NULL) 193 return NULL; 194 return container_of(clc, struct htb_class, common); 195} 196 197static unsigned long htb_search(struct Qdisc *sch, u32 handle) 198{ 199 return (unsigned long)htb_find(handle, sch); 200} 201 202#define HTB_DIRECT ((struct htb_class *)-1L) 203 204/** 205 * htb_classify - classify a packet into class 206 * @skb: the socket buffer 207 * @sch: the active queue discipline 208 * @qerr: pointer for returned status code 209 * 210 * It returns NULL if the packet should be dropped or -1 if the packet 211 * should be passed directly thru. In all other cases leaf class is returned. 212 * We allow direct class selection by classid in priority. The we examine 213 * filters in qdisc and in inner nodes (if higher filter points to the inner 214 * node). If we end up with classid MAJOR:0 we enqueue the skb into special 215 * internal fifo (direct). These packets then go directly thru. If we still 216 * have no valid leaf we try to use MAJOR:default leaf. It still unsuccessful 217 * then finish and return direct queue. 218 */ 219static struct htb_class *htb_classify(struct sk_buff *skb, struct Qdisc *sch, 220 int *qerr) 221{ 222 struct htb_sched *q = qdisc_priv(sch); 223 struct htb_class *cl; 224 struct tcf_result res; 225 struct tcf_proto *tcf; 226 int result; 227 228 /* allow to select class by setting skb->priority to valid classid; 229 * note that nfmark can be used too by attaching filter fw with no 230 * rules in it 231 */ 232 if (skb->priority == sch->handle) 233 return HTB_DIRECT; /* X:0 (direct flow) selected */ 234 cl = htb_find(skb->priority, sch); 235 if (cl) { 236 if (cl->level == 0) 237 return cl; 238 /* Start with inner filter chain if a non-leaf class is selected */ 239 tcf = rcu_dereference_bh(cl->filter_list); 240 } else { 241 tcf = rcu_dereference_bh(q->filter_list); 242 } 243 244 *qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS; 245 while (tcf && (result = tcf_classify(skb, NULL, tcf, &res, false)) >= 0) { 246#ifdef CONFIG_NET_CLS_ACT 247 switch (result) { 248 case TC_ACT_QUEUED: 249 case TC_ACT_STOLEN: 250 case TC_ACT_TRAP: 251 *qerr = NET_XMIT_SUCCESS | __NET_XMIT_STOLEN; 252 fallthrough; 253 case TC_ACT_SHOT: 254 return NULL; 255 } 256#endif 257 cl = (void *)res.class; 258 if (!cl) { 259 if (res.classid == sch->handle) 260 return HTB_DIRECT; /* X:0 (direct flow) */ 261 cl = htb_find(res.classid, sch); 262 if (!cl) 263 break; /* filter selected invalid classid */ 264 } 265 if (!cl->level) 266 return cl; /* we hit leaf; return it */ 267 268 /* we have got inner class; apply inner filter chain */ 269 tcf = rcu_dereference_bh(cl->filter_list); 270 } 271 /* classification failed; try to use default class */ 272 cl = htb_find(TC_H_MAKE(TC_H_MAJ(sch->handle), q->defcls), sch); 273 if (!cl || cl->level) 274 return HTB_DIRECT; /* bad default .. this is safe bet */ 275 return cl; 276} 277 278/** 279 * htb_add_to_id_tree - adds class to the round robin list 280 * @root: the root of the tree 281 * @cl: the class to add 282 * @prio: the give prio in class 283 * 284 * Routine adds class to the list (actually tree) sorted by classid. 285 * Make sure that class is not already on such list for given prio. 286 */ 287static void htb_add_to_id_tree(struct rb_root *root, 288 struct htb_class *cl, int prio) 289{ 290 struct rb_node **p = &root->rb_node, *parent = NULL; 291 292 while (*p) { 293 struct htb_class *c; 294 parent = *p; 295 c = rb_entry(parent, struct htb_class, node[prio]); 296 297 if (cl->common.classid > c->common.classid) 298 p = &parent->rb_right; 299 else 300 p = &parent->rb_left; 301 } 302 rb_link_node(&cl->node[prio], parent, p); 303 rb_insert_color(&cl->node[prio], root); 304} 305 306/** 307 * htb_add_to_wait_tree - adds class to the event queue with delay 308 * @q: the priority event queue 309 * @cl: the class to add 310 * @delay: delay in microseconds 311 * 312 * The class is added to priority event queue to indicate that class will 313 * change its mode in cl->pq_key microseconds. Make sure that class is not 314 * already in the queue. 315 */ 316static void htb_add_to_wait_tree(struct htb_sched *q, 317 struct htb_class *cl, s64 delay) 318{ 319 struct rb_node **p = &q->hlevel[cl->level].wait_pq.rb_node, *parent = NULL; 320 321 cl->pq_key = q->now + delay; 322 if (cl->pq_key == q->now) 323 cl->pq_key++; 324 325 /* update the nearest event cache */ 326 if (q->near_ev_cache[cl->level] > cl->pq_key) 327 q->near_ev_cache[cl->level] = cl->pq_key; 328 329 while (*p) { 330 struct htb_class *c; 331 parent = *p; 332 c = rb_entry(parent, struct htb_class, pq_node); 333 if (cl->pq_key >= c->pq_key) 334 p = &parent->rb_right; 335 else 336 p = &parent->rb_left; 337 } 338 rb_link_node(&cl->pq_node, parent, p); 339 rb_insert_color(&cl->pq_node, &q->hlevel[cl->level].wait_pq); 340} 341 342/** 343 * htb_next_rb_node - finds next node in binary tree 344 * @n: the current node in binary tree 345 * 346 * When we are past last key we return NULL. 347 * Average complexity is 2 steps per call. 348 */ 349static inline void htb_next_rb_node(struct rb_node **n) 350{ 351 *n = rb_next(*n); 352} 353 354/** 355 * htb_add_class_to_row - add class to its row 356 * @q: the priority event queue 357 * @cl: the class to add 358 * @mask: the given priorities in class in bitmap 359 * 360 * The class is added to row at priorities marked in mask. 361 * It does nothing if mask == 0. 362 */ 363static inline void htb_add_class_to_row(struct htb_sched *q, 364 struct htb_class *cl, int mask) 365{ 366 q->row_mask[cl->level] |= mask; 367 while (mask) { 368 int prio = ffz(~mask); 369 mask &= ~(1 << prio); 370 htb_add_to_id_tree(&q->hlevel[cl->level].hprio[prio].row, cl, prio); 371 } 372} 373 374/* If this triggers, it is a bug in this code, but it need not be fatal */ 375static void htb_safe_rb_erase(struct rb_node *rb, struct rb_root *root) 376{ 377 if (RB_EMPTY_NODE(rb)) { 378 WARN_ON(1); 379 } else { 380 rb_erase(rb, root); 381 RB_CLEAR_NODE(rb); 382 } 383} 384 385 386/** 387 * htb_remove_class_from_row - removes class from its row 388 * @q: the priority event queue 389 * @cl: the class to add 390 * @mask: the given priorities in class in bitmap 391 * 392 * The class is removed from row at priorities marked in mask. 393 * It does nothing if mask == 0. 394 */ 395static inline void htb_remove_class_from_row(struct htb_sched *q, 396 struct htb_class *cl, int mask) 397{ 398 int m = 0; 399 struct htb_level *hlevel = &q->hlevel[cl->level]; 400 401 while (mask) { 402 int prio = ffz(~mask); 403 struct htb_prio *hprio = &hlevel->hprio[prio]; 404 405 mask &= ~(1 << prio); 406 if (hprio->ptr == cl->node + prio) 407 htb_next_rb_node(&hprio->ptr); 408 409 htb_safe_rb_erase(cl->node + prio, &hprio->row); 410 if (!hprio->row.rb_node) 411 m |= 1 << prio; 412 } 413 q->row_mask[cl->level] &= ~m; 414} 415 416/** 417 * htb_activate_prios - creates active classe's feed chain 418 * @q: the priority event queue 419 * @cl: the class to activate 420 * 421 * The class is connected to ancestors and/or appropriate rows 422 * for priorities it is participating on. cl->cmode must be new 423 * (activated) mode. It does nothing if cl->prio_activity == 0. 424 */ 425static void htb_activate_prios(struct htb_sched *q, struct htb_class *cl) 426{ 427 struct htb_class *p = cl->parent; 428 long m, mask = cl->prio_activity; 429 430 while (cl->cmode == HTB_MAY_BORROW && p && mask) { 431 m = mask; 432 while (m) { 433 unsigned int prio = ffz(~m); 434 435 if (WARN_ON_ONCE(prio >= ARRAY_SIZE(p->inner.clprio))) 436 break; 437 m &= ~(1 << prio); 438 439 if (p->inner.clprio[prio].feed.rb_node) 440 /* parent already has its feed in use so that 441 * reset bit in mask as parent is already ok 442 */ 443 mask &= ~(1 << prio); 444 445 htb_add_to_id_tree(&p->inner.clprio[prio].feed, cl, prio); 446 } 447 p->prio_activity |= mask; 448 cl = p; 449 p = cl->parent; 450 451 } 452 if (cl->cmode == HTB_CAN_SEND && mask) 453 htb_add_class_to_row(q, cl, mask); 454} 455 456/** 457 * htb_deactivate_prios - remove class from feed chain 458 * @q: the priority event queue 459 * @cl: the class to deactivate 460 * 461 * cl->cmode must represent old mode (before deactivation). It does 462 * nothing if cl->prio_activity == 0. Class is removed from all feed 463 * chains and rows. 464 */ 465static void htb_deactivate_prios(struct htb_sched *q, struct htb_class *cl) 466{ 467 struct htb_class *p = cl->parent; 468 long m, mask = cl->prio_activity; 469 470 while (cl->cmode == HTB_MAY_BORROW && p && mask) { 471 m = mask; 472 mask = 0; 473 while (m) { 474 int prio = ffz(~m); 475 m &= ~(1 << prio); 476 477 if (p->inner.clprio[prio].ptr == cl->node + prio) { 478 /* we are removing child which is pointed to from 479 * parent feed - forget the pointer but remember 480 * classid 481 */ 482 p->inner.clprio[prio].last_ptr_id = cl->common.classid; 483 p->inner.clprio[prio].ptr = NULL; 484 } 485 486 htb_safe_rb_erase(cl->node + prio, 487 &p->inner.clprio[prio].feed); 488 489 if (!p->inner.clprio[prio].feed.rb_node) 490 mask |= 1 << prio; 491 } 492 493 p->prio_activity &= ~mask; 494 cl = p; 495 p = cl->parent; 496 497 } 498 if (cl->cmode == HTB_CAN_SEND && mask) 499 htb_remove_class_from_row(q, cl, mask); 500} 501 502static inline s64 htb_lowater(const struct htb_class *cl) 503{ 504 if (htb_hysteresis) 505 return cl->cmode != HTB_CANT_SEND ? -cl->cbuffer : 0; 506 else 507 return 0; 508} 509static inline s64 htb_hiwater(const struct htb_class *cl) 510{ 511 if (htb_hysteresis) 512 return cl->cmode == HTB_CAN_SEND ? -cl->buffer : 0; 513 else 514 return 0; 515} 516 517 518/** 519 * htb_class_mode - computes and returns current class mode 520 * @cl: the target class 521 * @diff: diff time in microseconds 522 * 523 * It computes cl's mode at time cl->t_c+diff and returns it. If mode 524 * is not HTB_CAN_SEND then cl->pq_key is updated to time difference 525 * from now to time when cl will change its state. 526 * Also it is worth to note that class mode doesn't change simply 527 * at cl->{c,}tokens == 0 but there can rather be hysteresis of 528 * 0 .. -cl->{c,}buffer range. It is meant to limit number of 529 * mode transitions per time unit. The speed gain is about 1/6. 530 */ 531static inline enum htb_cmode 532htb_class_mode(struct htb_class *cl, s64 *diff) 533{ 534 s64 toks; 535 536 if ((toks = (cl->ctokens + *diff)) < htb_lowater(cl)) { 537 *diff = -toks; 538 return HTB_CANT_SEND; 539 } 540 541 if ((toks = (cl->tokens + *diff)) >= htb_hiwater(cl)) 542 return HTB_CAN_SEND; 543 544 *diff = -toks; 545 return HTB_MAY_BORROW; 546} 547 548/** 549 * htb_change_class_mode - changes classe's mode 550 * @q: the priority event queue 551 * @cl: the target class 552 * @diff: diff time in microseconds 553 * 554 * This should be the only way how to change classe's mode under normal 555 * circumstances. Routine will update feed lists linkage, change mode 556 * and add class to the wait event queue if appropriate. New mode should 557 * be different from old one and cl->pq_key has to be valid if changing 558 * to mode other than HTB_CAN_SEND (see htb_add_to_wait_tree). 559 */ 560static void 561htb_change_class_mode(struct htb_sched *q, struct htb_class *cl, s64 *diff) 562{ 563 enum htb_cmode new_mode = htb_class_mode(cl, diff); 564 565 if (new_mode == cl->cmode) 566 return; 567 568 if (new_mode == HTB_CANT_SEND) { 569 cl->overlimits++; 570 q->overlimits++; 571 } 572 573 if (cl->prio_activity) { /* not necessary: speed optimization */ 574 if (cl->cmode != HTB_CANT_SEND) 575 htb_deactivate_prios(q, cl); 576 cl->cmode = new_mode; 577 if (new_mode != HTB_CANT_SEND) 578 htb_activate_prios(q, cl); 579 } else 580 cl->cmode = new_mode; 581} 582 583/** 584 * htb_activate - inserts leaf cl into appropriate active feeds 585 * @q: the priority event queue 586 * @cl: the target class 587 * 588 * Routine learns (new) priority of leaf and activates feed chain 589 * for the prio. It can be called on already active leaf safely. 590 * It also adds leaf into droplist. 591 */ 592static inline void htb_activate(struct htb_sched *q, struct htb_class *cl) 593{ 594 WARN_ON(cl->level || !cl->leaf.q || !cl->leaf.q->q.qlen); 595 596 if (!cl->prio_activity) { 597 cl->prio_activity = 1 << cl->prio; 598 htb_activate_prios(q, cl); 599 } 600} 601 602/** 603 * htb_deactivate - remove leaf cl from active feeds 604 * @q: the priority event queue 605 * @cl: the target class 606 * 607 * Make sure that leaf is active. In the other words it can't be called 608 * with non-active leaf. It also removes class from the drop list. 609 */ 610static inline void htb_deactivate(struct htb_sched *q, struct htb_class *cl) 611{ 612 WARN_ON(!cl->prio_activity); 613 614 htb_deactivate_prios(q, cl); 615 cl->prio_activity = 0; 616} 617 618static int htb_enqueue(struct sk_buff *skb, struct Qdisc *sch, 619 struct sk_buff **to_free) 620{ 621 int ret; 622 unsigned int len = qdisc_pkt_len(skb); 623 struct htb_sched *q = qdisc_priv(sch); 624 struct htb_class *cl = htb_classify(skb, sch, &ret); 625 626 if (cl == HTB_DIRECT) { 627 /* enqueue to helper queue */ 628 if (q->direct_queue.qlen < q->direct_qlen) { 629 __qdisc_enqueue_tail(skb, &q->direct_queue); 630 q->direct_pkts++; 631 } else { 632 return qdisc_drop(skb, sch, to_free); 633 } 634#ifdef CONFIG_NET_CLS_ACT 635 } else if (!cl) { 636 if (ret & __NET_XMIT_BYPASS) 637 qdisc_qstats_drop(sch); 638 __qdisc_drop(skb, to_free); 639 return ret; 640#endif 641 } else if ((ret = qdisc_enqueue(skb, cl->leaf.q, 642 to_free)) != NET_XMIT_SUCCESS) { 643 if (net_xmit_drop_count(ret)) { 644 qdisc_qstats_drop(sch); 645 cl->drops++; 646 } 647 return ret; 648 } else { 649 htb_activate(q, cl); 650 } 651 652 sch->qstats.backlog += len; 653 sch->q.qlen++; 654 return NET_XMIT_SUCCESS; 655} 656 657static inline void htb_accnt_tokens(struct htb_class *cl, int bytes, s64 diff) 658{ 659 s64 toks = diff + cl->tokens; 660 661 if (toks > cl->buffer) 662 toks = cl->buffer; 663 toks -= (s64) psched_l2t_ns(&cl->rate, bytes); 664 if (toks <= -cl->mbuffer) 665 toks = 1 - cl->mbuffer; 666 667 cl->tokens = toks; 668} 669 670static inline void htb_accnt_ctokens(struct htb_class *cl, int bytes, s64 diff) 671{ 672 s64 toks = diff + cl->ctokens; 673 674 if (toks > cl->cbuffer) 675 toks = cl->cbuffer; 676 toks -= (s64) psched_l2t_ns(&cl->ceil, bytes); 677 if (toks <= -cl->mbuffer) 678 toks = 1 - cl->mbuffer; 679 680 cl->ctokens = toks; 681} 682 683/** 684 * htb_charge_class - charges amount "bytes" to leaf and ancestors 685 * @q: the priority event queue 686 * @cl: the class to start iterate 687 * @level: the minimum level to account 688 * @skb: the socket buffer 689 * 690 * Routine assumes that packet "bytes" long was dequeued from leaf cl 691 * borrowing from "level". It accounts bytes to ceil leaky bucket for 692 * leaf and all ancestors and to rate bucket for ancestors at levels 693 * "level" and higher. It also handles possible change of mode resulting 694 * from the update. Note that mode can also increase here (MAY_BORROW to 695 * CAN_SEND) because we can use more precise clock that event queue here. 696 * In such case we remove class from event queue first. 697 */ 698static void htb_charge_class(struct htb_sched *q, struct htb_class *cl, 699 int level, struct sk_buff *skb) 700{ 701 int bytes = qdisc_pkt_len(skb); 702 enum htb_cmode old_mode; 703 s64 diff; 704 705 while (cl) { 706 diff = min_t(s64, q->now - cl->t_c, cl->mbuffer); 707 if (cl->level >= level) { 708 if (cl->level == level) 709 cl->xstats.lends++; 710 htb_accnt_tokens(cl, bytes, diff); 711 } else { 712 cl->xstats.borrows++; 713 cl->tokens += diff; /* we moved t_c; update tokens */ 714 } 715 htb_accnt_ctokens(cl, bytes, diff); 716 cl->t_c = q->now; 717 718 old_mode = cl->cmode; 719 diff = 0; 720 htb_change_class_mode(q, cl, &diff); 721 if (old_mode != cl->cmode) { 722 if (old_mode != HTB_CAN_SEND) 723 htb_safe_rb_erase(&cl->pq_node, &q->hlevel[cl->level].wait_pq); 724 if (cl->cmode != HTB_CAN_SEND) 725 htb_add_to_wait_tree(q, cl, diff); 726 } 727 728 /* update basic stats except for leaves which are already updated */ 729 if (cl->level) 730 bstats_update(&cl->bstats, skb); 731 732 cl = cl->parent; 733 } 734} 735 736/** 737 * htb_do_events - make mode changes to classes at the level 738 * @q: the priority event queue 739 * @level: which wait_pq in 'q->hlevel' 740 * @start: start jiffies 741 * 742 * Scans event queue for pending events and applies them. Returns time of 743 * next pending event (0 for no event in pq, q->now for too many events). 744 * Note: Applied are events whose have cl->pq_key <= q->now. 745 */ 746static s64 htb_do_events(struct htb_sched *q, const int level, 747 unsigned long start) 748{ 749 /* don't run for longer than 2 jiffies; 2 is used instead of 750 * 1 to simplify things when jiffy is going to be incremented 751 * too soon 752 */ 753 unsigned long stop_at = start + 2; 754 struct rb_root *wait_pq = &q->hlevel[level].wait_pq; 755 756 while (time_before(jiffies, stop_at)) { 757 struct htb_class *cl; 758 s64 diff; 759 struct rb_node *p = rb_first(wait_pq); 760 761 if (!p) 762 return 0; 763 764 cl = rb_entry(p, struct htb_class, pq_node); 765 if (cl->pq_key > q->now) 766 return cl->pq_key; 767 768 htb_safe_rb_erase(p, wait_pq); 769 diff = min_t(s64, q->now - cl->t_c, cl->mbuffer); 770 htb_change_class_mode(q, cl, &diff); 771 if (cl->cmode != HTB_CAN_SEND) 772 htb_add_to_wait_tree(q, cl, diff); 773 } 774 775 /* too much load - let's continue after a break for scheduling */ 776 if (!(q->warned & HTB_WARN_TOOMANYEVENTS)) { 777 pr_warn("htb: too many events!\n"); 778 q->warned |= HTB_WARN_TOOMANYEVENTS; 779 } 780 781 return q->now; 782} 783 784/* Returns class->node+prio from id-tree where classe's id is >= id. NULL 785 * is no such one exists. 786 */ 787static struct rb_node *htb_id_find_next_upper(int prio, struct rb_node *n, 788 u32 id) 789{ 790 struct rb_node *r = NULL; 791 while (n) { 792 struct htb_class *cl = 793 rb_entry(n, struct htb_class, node[prio]); 794 795 if (id > cl->common.classid) { 796 n = n->rb_right; 797 } else if (id < cl->common.classid) { 798 r = n; 799 n = n->rb_left; 800 } else { 801 return n; 802 } 803 } 804 return r; 805} 806 807/** 808 * htb_lookup_leaf - returns next leaf class in DRR order 809 * @hprio: the current one 810 * @prio: which prio in class 811 * 812 * Find leaf where current feed pointers points to. 813 */ 814static struct htb_class *htb_lookup_leaf(struct htb_prio *hprio, const int prio) 815{ 816 int i; 817 struct { 818 struct rb_node *root; 819 struct rb_node **pptr; 820 u32 *pid; 821 } stk[TC_HTB_MAXDEPTH], *sp = stk; 822 823 BUG_ON(!hprio->row.rb_node); 824 sp->root = hprio->row.rb_node; 825 sp->pptr = &hprio->ptr; 826 sp->pid = &hprio->last_ptr_id; 827 828 for (i = 0; i < 65535; i++) { 829 if (!*sp->pptr && *sp->pid) { 830 /* ptr was invalidated but id is valid - try to recover 831 * the original or next ptr 832 */ 833 *sp->pptr = 834 htb_id_find_next_upper(prio, sp->root, *sp->pid); 835 } 836 *sp->pid = 0; /* ptr is valid now so that remove this hint as it 837 * can become out of date quickly 838 */ 839 if (!*sp->pptr) { /* we are at right end; rewind & go up */ 840 *sp->pptr = sp->root; 841 while ((*sp->pptr)->rb_left) 842 *sp->pptr = (*sp->pptr)->rb_left; 843 if (sp > stk) { 844 sp--; 845 if (!*sp->pptr) { 846 WARN_ON(1); 847 return NULL; 848 } 849 htb_next_rb_node(sp->pptr); 850 } 851 } else { 852 struct htb_class *cl; 853 struct htb_prio *clp; 854 855 cl = rb_entry(*sp->pptr, struct htb_class, node[prio]); 856 if (!cl->level) 857 return cl; 858 clp = &cl->inner.clprio[prio]; 859 (++sp)->root = clp->feed.rb_node; 860 sp->pptr = &clp->ptr; 861 sp->pid = &clp->last_ptr_id; 862 } 863 } 864 WARN_ON(1); 865 return NULL; 866} 867 868/* dequeues packet at given priority and level; call only if 869 * you are sure that there is active class at prio/level 870 */ 871static struct sk_buff *htb_dequeue_tree(struct htb_sched *q, const int prio, 872 const int level) 873{ 874 struct sk_buff *skb = NULL; 875 struct htb_class *cl, *start; 876 struct htb_level *hlevel = &q->hlevel[level]; 877 struct htb_prio *hprio = &hlevel->hprio[prio]; 878 879 /* look initial class up in the row */ 880 start = cl = htb_lookup_leaf(hprio, prio); 881 882 do { 883next: 884 if (unlikely(!cl)) 885 return NULL; 886 887 /* class can be empty - it is unlikely but can be true if leaf 888 * qdisc drops packets in enqueue routine or if someone used 889 * graft operation on the leaf since last dequeue; 890 * simply deactivate and skip such class 891 */ 892 if (unlikely(cl->leaf.q->q.qlen == 0)) { 893 struct htb_class *next; 894 htb_deactivate(q, cl); 895 896 /* row/level might become empty */ 897 if ((q->row_mask[level] & (1 << prio)) == 0) 898 return NULL; 899 900 next = htb_lookup_leaf(hprio, prio); 901 902 if (cl == start) /* fix start if we just deleted it */ 903 start = next; 904 cl = next; 905 goto next; 906 } 907 908 skb = cl->leaf.q->dequeue(cl->leaf.q); 909 if (likely(skb != NULL)) 910 break; 911 912 qdisc_warn_nonwc("htb", cl->leaf.q); 913 htb_next_rb_node(level ? &cl->parent->inner.clprio[prio].ptr: 914 &q->hlevel[0].hprio[prio].ptr); 915 cl = htb_lookup_leaf(hprio, prio); 916 917 } while (cl != start); 918 919 if (likely(skb != NULL)) { 920 bstats_update(&cl->bstats, skb); 921 cl->leaf.deficit[level] -= qdisc_pkt_len(skb); 922 if (cl->leaf.deficit[level] < 0) { 923 cl->leaf.deficit[level] += cl->quantum; 924 htb_next_rb_node(level ? &cl->parent->inner.clprio[prio].ptr : 925 &q->hlevel[0].hprio[prio].ptr); 926 } 927 /* this used to be after charge_class but this constelation 928 * gives us slightly better performance 929 */ 930 if (!cl->leaf.q->q.qlen) 931 htb_deactivate(q, cl); 932 htb_charge_class(q, cl, level, skb); 933 } 934 return skb; 935} 936 937static struct sk_buff *htb_dequeue(struct Qdisc *sch) 938{ 939 struct sk_buff *skb; 940 struct htb_sched *q = qdisc_priv(sch); 941 int level; 942 s64 next_event; 943 unsigned long start_at; 944 945 /* try to dequeue direct packets as high prio (!) to minimize cpu work */ 946 skb = __qdisc_dequeue_head(&q->direct_queue); 947 if (skb != NULL) { 948ok: 949 qdisc_bstats_update(sch, skb); 950 qdisc_qstats_backlog_dec(sch, skb); 951 sch->q.qlen--; 952 return skb; 953 } 954 955 if (!sch->q.qlen) 956 goto fin; 957 q->now = ktime_get_ns(); 958 start_at = jiffies; 959 960 next_event = q->now + 5LLU * NSEC_PER_SEC; 961 962 for (level = 0; level < TC_HTB_MAXDEPTH; level++) { 963 /* common case optimization - skip event handler quickly */ 964 int m; 965 s64 event = q->near_ev_cache[level]; 966 967 if (q->now >= event) { 968 event = htb_do_events(q, level, start_at); 969 if (!event) 970 event = q->now + NSEC_PER_SEC; 971 q->near_ev_cache[level] = event; 972 } 973 974 if (next_event > event) 975 next_event = event; 976 977 m = ~q->row_mask[level]; 978 while (m != (int)(-1)) { 979 int prio = ffz(m); 980 981 m |= 1 << prio; 982 skb = htb_dequeue_tree(q, prio, level); 983 if (likely(skb != NULL)) 984 goto ok; 985 } 986 } 987 if (likely(next_event > q->now)) 988 qdisc_watchdog_schedule_ns(&q->watchdog, next_event); 989 else 990 schedule_work(&q->work); 991fin: 992 return skb; 993} 994 995/* reset all classes */ 996/* always caled under BH & queue lock */ 997static void htb_reset(struct Qdisc *sch) 998{ 999 struct htb_sched *q = qdisc_priv(sch); 1000 struct htb_class *cl; 1001 unsigned int i; 1002 1003 for (i = 0; i < q->clhash.hashsize; i++) { 1004 hlist_for_each_entry(cl, &q->clhash.hash[i], common.hnode) { 1005 if (cl->level) 1006 memset(&cl->inner, 0, sizeof(cl->inner)); 1007 else { 1008 if (cl->leaf.q && !q->offload) 1009 qdisc_reset(cl->leaf.q); 1010 } 1011 cl->prio_activity = 0; 1012 cl->cmode = HTB_CAN_SEND; 1013 } 1014 } 1015 qdisc_watchdog_cancel(&q->watchdog); 1016 __qdisc_reset_queue(&q->direct_queue); 1017 memset(q->hlevel, 0, sizeof(q->hlevel)); 1018 memset(q->row_mask, 0, sizeof(q->row_mask)); 1019} 1020 1021static const struct nla_policy htb_policy[TCA_HTB_MAX + 1] = { 1022 [TCA_HTB_PARMS] = { .len = sizeof(struct tc_htb_opt) }, 1023 [TCA_HTB_INIT] = { .len = sizeof(struct tc_htb_glob) }, 1024 [TCA_HTB_CTAB] = { .type = NLA_BINARY, .len = TC_RTAB_SIZE }, 1025 [TCA_HTB_RTAB] = { .type = NLA_BINARY, .len = TC_RTAB_SIZE }, 1026 [TCA_HTB_DIRECT_QLEN] = { .type = NLA_U32 }, 1027 [TCA_HTB_RATE64] = { .type = NLA_U64 }, 1028 [TCA_HTB_CEIL64] = { .type = NLA_U64 }, 1029 [TCA_HTB_OFFLOAD] = { .type = NLA_FLAG }, 1030}; 1031 1032static void htb_work_func(struct work_struct *work) 1033{ 1034 struct htb_sched *q = container_of(work, struct htb_sched, work); 1035 struct Qdisc *sch = q->watchdog.qdisc; 1036 1037 rcu_read_lock(); 1038 __netif_schedule(qdisc_root(sch)); 1039 rcu_read_unlock(); 1040} 1041 1042static void htb_set_lockdep_class_child(struct Qdisc *q) 1043{ 1044 static struct lock_class_key child_key; 1045 1046 lockdep_set_class(qdisc_lock(q), &child_key); 1047} 1048 1049static int htb_offload(struct net_device *dev, struct tc_htb_qopt_offload *opt) 1050{ 1051 return dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_QDISC_HTB, opt); 1052} 1053 1054static int htb_init(struct Qdisc *sch, struct nlattr *opt, 1055 struct netlink_ext_ack *extack) 1056{ 1057 struct net_device *dev = qdisc_dev(sch); 1058 struct tc_htb_qopt_offload offload_opt; 1059 struct htb_sched *q = qdisc_priv(sch); 1060 struct nlattr *tb[TCA_HTB_MAX + 1]; 1061 struct tc_htb_glob *gopt; 1062 unsigned int ntx; 1063 bool offload; 1064 int err; 1065 1066 qdisc_watchdog_init(&q->watchdog, sch); 1067 INIT_WORK(&q->work, htb_work_func); 1068 1069 if (!opt) 1070 return -EINVAL; 1071 1072 err = tcf_block_get(&q->block, &q->filter_list, sch, extack); 1073 if (err) 1074 return err; 1075 1076 err = nla_parse_nested_deprecated(tb, TCA_HTB_MAX, opt, htb_policy, 1077 NULL); 1078 if (err < 0) 1079 return err; 1080 1081 if (!tb[TCA_HTB_INIT]) 1082 return -EINVAL; 1083 1084 gopt = nla_data(tb[TCA_HTB_INIT]); 1085 if (gopt->version != HTB_VER >> 16) 1086 return -EINVAL; 1087 1088 offload = nla_get_flag(tb[TCA_HTB_OFFLOAD]); 1089 1090 if (offload) { 1091 if (sch->parent != TC_H_ROOT) { 1092 NL_SET_ERR_MSG(extack, "HTB must be the root qdisc to use offload"); 1093 return -EOPNOTSUPP; 1094 } 1095 1096 if (!tc_can_offload(dev) || !dev->netdev_ops->ndo_setup_tc) { 1097 NL_SET_ERR_MSG(extack, "hw-tc-offload ethtool feature flag must be on"); 1098 return -EOPNOTSUPP; 1099 } 1100 1101 q->num_direct_qdiscs = dev->real_num_tx_queues; 1102 q->direct_qdiscs = kcalloc(q->num_direct_qdiscs, 1103 sizeof(*q->direct_qdiscs), 1104 GFP_KERNEL); 1105 if (!q->direct_qdiscs) 1106 return -ENOMEM; 1107 } 1108 1109 err = qdisc_class_hash_init(&q->clhash); 1110 if (err < 0) 1111 return err; 1112 1113 if (tb[TCA_HTB_DIRECT_QLEN]) 1114 q->direct_qlen = nla_get_u32(tb[TCA_HTB_DIRECT_QLEN]); 1115 else 1116 q->direct_qlen = qdisc_dev(sch)->tx_queue_len; 1117 1118 if ((q->rate2quantum = gopt->rate2quantum) < 1) 1119 q->rate2quantum = 1; 1120 q->defcls = gopt->defcls; 1121 1122 if (!offload) 1123 return 0; 1124 1125 for (ntx = 0; ntx < q->num_direct_qdiscs; ntx++) { 1126 struct netdev_queue *dev_queue = netdev_get_tx_queue(dev, ntx); 1127 struct Qdisc *qdisc; 1128 1129 qdisc = qdisc_create_dflt(dev_queue, &pfifo_qdisc_ops, 1130 TC_H_MAKE(sch->handle, 0), extack); 1131 if (!qdisc) { 1132 return -ENOMEM; 1133 } 1134 1135 htb_set_lockdep_class_child(qdisc); 1136 q->direct_qdiscs[ntx] = qdisc; 1137 qdisc->flags |= TCQ_F_ONETXQUEUE | TCQ_F_NOPARENT; 1138 } 1139 1140 sch->flags |= TCQ_F_MQROOT; 1141 1142 offload_opt = (struct tc_htb_qopt_offload) { 1143 .command = TC_HTB_CREATE, 1144 .parent_classid = TC_H_MAJ(sch->handle) >> 16, 1145 .classid = TC_H_MIN(q->defcls), 1146 .extack = extack, 1147 }; 1148 err = htb_offload(dev, &offload_opt); 1149 if (err) 1150 return err; 1151 1152 /* Defer this assignment, so that htb_destroy skips offload-related 1153 * parts (especially calling ndo_setup_tc) on errors. 1154 */ 1155 q->offload = true; 1156 1157 return 0; 1158} 1159 1160static void htb_attach_offload(struct Qdisc *sch) 1161{ 1162 struct net_device *dev = qdisc_dev(sch); 1163 struct htb_sched *q = qdisc_priv(sch); 1164 unsigned int ntx; 1165 1166 for (ntx = 0; ntx < q->num_direct_qdiscs; ntx++) { 1167 struct Qdisc *old, *qdisc = q->direct_qdiscs[ntx]; 1168 1169 old = dev_graft_qdisc(qdisc->dev_queue, qdisc); 1170 qdisc_put(old); 1171 qdisc_hash_add(qdisc, false); 1172 } 1173 for (ntx = q->num_direct_qdiscs; ntx < dev->num_tx_queues; ntx++) { 1174 struct netdev_queue *dev_queue = netdev_get_tx_queue(dev, ntx); 1175 struct Qdisc *old = dev_graft_qdisc(dev_queue, NULL); 1176 1177 qdisc_put(old); 1178 } 1179 1180 kfree(q->direct_qdiscs); 1181 q->direct_qdiscs = NULL; 1182} 1183 1184static void htb_attach_software(struct Qdisc *sch) 1185{ 1186 struct net_device *dev = qdisc_dev(sch); 1187 unsigned int ntx; 1188 1189 /* Resemble qdisc_graft behavior. */ 1190 for (ntx = 0; ntx < dev->num_tx_queues; ntx++) { 1191 struct netdev_queue *dev_queue = netdev_get_tx_queue(dev, ntx); 1192 struct Qdisc *old = dev_graft_qdisc(dev_queue, sch); 1193 1194 qdisc_refcount_inc(sch); 1195 1196 qdisc_put(old); 1197 } 1198} 1199 1200static void htb_attach(struct Qdisc *sch) 1201{ 1202 struct htb_sched *q = qdisc_priv(sch); 1203 1204 if (q->offload) 1205 htb_attach_offload(sch); 1206 else 1207 htb_attach_software(sch); 1208} 1209 1210static int htb_dump(struct Qdisc *sch, struct sk_buff *skb) 1211{ 1212 struct htb_sched *q = qdisc_priv(sch); 1213 struct nlattr *nest; 1214 struct tc_htb_glob gopt; 1215 1216 if (q->offload) 1217 sch->flags |= TCQ_F_OFFLOADED; 1218 else 1219 sch->flags &= ~TCQ_F_OFFLOADED; 1220 1221 sch->qstats.overlimits = q->overlimits; 1222 /* Its safe to not acquire qdisc lock. As we hold RTNL, 1223 * no change can happen on the qdisc parameters. 1224 */ 1225 1226 gopt.direct_pkts = q->direct_pkts; 1227 gopt.version = HTB_VER; 1228 gopt.rate2quantum = q->rate2quantum; 1229 gopt.defcls = q->defcls; 1230 gopt.debug = 0; 1231 1232 nest = nla_nest_start_noflag(skb, TCA_OPTIONS); 1233 if (nest == NULL) 1234 goto nla_put_failure; 1235 if (nla_put(skb, TCA_HTB_INIT, sizeof(gopt), &gopt) || 1236 nla_put_u32(skb, TCA_HTB_DIRECT_QLEN, q->direct_qlen)) 1237 goto nla_put_failure; 1238 if (q->offload && nla_put_flag(skb, TCA_HTB_OFFLOAD)) 1239 goto nla_put_failure; 1240 1241 return nla_nest_end(skb, nest); 1242 1243nla_put_failure: 1244 nla_nest_cancel(skb, nest); 1245 return -1; 1246} 1247 1248static int htb_dump_class(struct Qdisc *sch, unsigned long arg, 1249 struct sk_buff *skb, struct tcmsg *tcm) 1250{ 1251 struct htb_class *cl = (struct htb_class *)arg; 1252 struct htb_sched *q = qdisc_priv(sch); 1253 struct nlattr *nest; 1254 struct tc_htb_opt opt; 1255 1256 /* Its safe to not acquire qdisc lock. As we hold RTNL, 1257 * no change can happen on the class parameters. 1258 */ 1259 tcm->tcm_parent = cl->parent ? cl->parent->common.classid : TC_H_ROOT; 1260 tcm->tcm_handle = cl->common.classid; 1261 if (!cl->level && cl->leaf.q) 1262 tcm->tcm_info = cl->leaf.q->handle; 1263 1264 nest = nla_nest_start_noflag(skb, TCA_OPTIONS); 1265 if (nest == NULL) 1266 goto nla_put_failure; 1267 1268 memset(&opt, 0, sizeof(opt)); 1269 1270 psched_ratecfg_getrate(&opt.rate, &cl->rate); 1271 opt.buffer = PSCHED_NS2TICKS(cl->buffer); 1272 psched_ratecfg_getrate(&opt.ceil, &cl->ceil); 1273 opt.cbuffer = PSCHED_NS2TICKS(cl->cbuffer); 1274 opt.quantum = cl->quantum; 1275 opt.prio = cl->prio; 1276 opt.level = cl->level; 1277 if (nla_put(skb, TCA_HTB_PARMS, sizeof(opt), &opt)) 1278 goto nla_put_failure; 1279 if (q->offload && nla_put_flag(skb, TCA_HTB_OFFLOAD)) 1280 goto nla_put_failure; 1281 if ((cl->rate.rate_bytes_ps >= (1ULL << 32)) && 1282 nla_put_u64_64bit(skb, TCA_HTB_RATE64, cl->rate.rate_bytes_ps, 1283 TCA_HTB_PAD)) 1284 goto nla_put_failure; 1285 if ((cl->ceil.rate_bytes_ps >= (1ULL << 32)) && 1286 nla_put_u64_64bit(skb, TCA_HTB_CEIL64, cl->ceil.rate_bytes_ps, 1287 TCA_HTB_PAD)) 1288 goto nla_put_failure; 1289 1290 return nla_nest_end(skb, nest); 1291 1292nla_put_failure: 1293 nla_nest_cancel(skb, nest); 1294 return -1; 1295} 1296 1297static void htb_offload_aggregate_stats(struct htb_sched *q, 1298 struct htb_class *cl) 1299{ 1300 u64 bytes = 0, packets = 0; 1301 struct htb_class *c; 1302 unsigned int i; 1303 1304 gnet_stats_basic_sync_init(&cl->bstats); 1305 1306 for (i = 0; i < q->clhash.hashsize; i++) { 1307 hlist_for_each_entry(c, &q->clhash.hash[i], common.hnode) { 1308 struct htb_class *p = c; 1309 1310 while (p && p->level < cl->level) 1311 p = p->parent; 1312 1313 if (p != cl) 1314 continue; 1315 1316 bytes += u64_stats_read(&c->bstats_bias.bytes); 1317 packets += u64_stats_read(&c->bstats_bias.packets); 1318 if (c->level == 0) { 1319 bytes += u64_stats_read(&c->leaf.q->bstats.bytes); 1320 packets += u64_stats_read(&c->leaf.q->bstats.packets); 1321 } 1322 } 1323 } 1324 _bstats_update(&cl->bstats, bytes, packets); 1325} 1326 1327static int 1328htb_dump_class_stats(struct Qdisc *sch, unsigned long arg, struct gnet_dump *d) 1329{ 1330 struct htb_class *cl = (struct htb_class *)arg; 1331 struct htb_sched *q = qdisc_priv(sch); 1332 struct gnet_stats_queue qs = { 1333 .drops = cl->drops, 1334 .overlimits = cl->overlimits, 1335 }; 1336 __u32 qlen = 0; 1337 1338 if (!cl->level && cl->leaf.q) 1339 qdisc_qstats_qlen_backlog(cl->leaf.q, &qlen, &qs.backlog); 1340 1341 cl->xstats.tokens = clamp_t(s64, PSCHED_NS2TICKS(cl->tokens), 1342 INT_MIN, INT_MAX); 1343 cl->xstats.ctokens = clamp_t(s64, PSCHED_NS2TICKS(cl->ctokens), 1344 INT_MIN, INT_MAX); 1345 1346 if (q->offload) { 1347 if (!cl->level) { 1348 if (cl->leaf.q) 1349 cl->bstats = cl->leaf.q->bstats; 1350 else 1351 gnet_stats_basic_sync_init(&cl->bstats); 1352 _bstats_update(&cl->bstats, 1353 u64_stats_read(&cl->bstats_bias.bytes), 1354 u64_stats_read(&cl->bstats_bias.packets)); 1355 } else { 1356 htb_offload_aggregate_stats(q, cl); 1357 } 1358 } 1359 1360 if (gnet_stats_copy_basic(d, NULL, &cl->bstats, true) < 0 || 1361 gnet_stats_copy_rate_est(d, &cl->rate_est) < 0 || 1362 gnet_stats_copy_queue(d, NULL, &qs, qlen) < 0) 1363 return -1; 1364 1365 return gnet_stats_copy_app(d, &cl->xstats, sizeof(cl->xstats)); 1366} 1367 1368static struct netdev_queue * 1369htb_select_queue(struct Qdisc *sch, struct tcmsg *tcm) 1370{ 1371 struct net_device *dev = qdisc_dev(sch); 1372 struct tc_htb_qopt_offload offload_opt; 1373 struct htb_sched *q = qdisc_priv(sch); 1374 int err; 1375 1376 if (!q->offload) 1377 return sch->dev_queue; 1378 1379 offload_opt = (struct tc_htb_qopt_offload) { 1380 .command = TC_HTB_LEAF_QUERY_QUEUE, 1381 .classid = TC_H_MIN(tcm->tcm_parent), 1382 }; 1383 err = htb_offload(dev, &offload_opt); 1384 if (err || offload_opt.qid >= dev->num_tx_queues) 1385 return NULL; 1386 return netdev_get_tx_queue(dev, offload_opt.qid); 1387} 1388 1389static struct Qdisc * 1390htb_graft_helper(struct netdev_queue *dev_queue, struct Qdisc *new_q) 1391{ 1392 struct net_device *dev = dev_queue->dev; 1393 struct Qdisc *old_q; 1394 1395 if (dev->flags & IFF_UP) 1396 dev_deactivate(dev); 1397 old_q = dev_graft_qdisc(dev_queue, new_q); 1398 if (new_q) 1399 new_q->flags |= TCQ_F_ONETXQUEUE | TCQ_F_NOPARENT; 1400 if (dev->flags & IFF_UP) 1401 dev_activate(dev); 1402 1403 return old_q; 1404} 1405 1406static struct netdev_queue *htb_offload_get_queue(struct htb_class *cl) 1407{ 1408 struct netdev_queue *queue; 1409 1410 queue = cl->leaf.offload_queue; 1411 if (!(cl->leaf.q->flags & TCQ_F_BUILTIN)) 1412 WARN_ON(cl->leaf.q->dev_queue != queue); 1413 1414 return queue; 1415} 1416 1417static void htb_offload_move_qdisc(struct Qdisc *sch, struct htb_class *cl_old, 1418 struct htb_class *cl_new, bool destroying) 1419{ 1420 struct netdev_queue *queue_old, *queue_new; 1421 struct net_device *dev = qdisc_dev(sch); 1422 1423 queue_old = htb_offload_get_queue(cl_old); 1424 queue_new = htb_offload_get_queue(cl_new); 1425 1426 if (!destroying) { 1427 struct Qdisc *qdisc; 1428 1429 if (dev->flags & IFF_UP) 1430 dev_deactivate(dev); 1431 qdisc = dev_graft_qdisc(queue_old, NULL); 1432 WARN_ON(qdisc != cl_old->leaf.q); 1433 } 1434 1435 if (!(cl_old->leaf.q->flags & TCQ_F_BUILTIN)) 1436 cl_old->leaf.q->dev_queue = queue_new; 1437 cl_old->leaf.offload_queue = queue_new; 1438 1439 if (!destroying) { 1440 struct Qdisc *qdisc; 1441 1442 qdisc = dev_graft_qdisc(queue_new, cl_old->leaf.q); 1443 if (dev->flags & IFF_UP) 1444 dev_activate(dev); 1445 WARN_ON(!(qdisc->flags & TCQ_F_BUILTIN)); 1446 } 1447} 1448 1449static int htb_graft(struct Qdisc *sch, unsigned long arg, struct Qdisc *new, 1450 struct Qdisc **old, struct netlink_ext_ack *extack) 1451{ 1452 struct netdev_queue *dev_queue = sch->dev_queue; 1453 struct htb_class *cl = (struct htb_class *)arg; 1454 struct htb_sched *q = qdisc_priv(sch); 1455 struct Qdisc *old_q; 1456 1457 if (cl->level) 1458 return -EINVAL; 1459 1460 if (q->offload) 1461 dev_queue = htb_offload_get_queue(cl); 1462 1463 if (!new) { 1464 new = qdisc_create_dflt(dev_queue, &pfifo_qdisc_ops, 1465 cl->common.classid, extack); 1466 if (!new) 1467 return -ENOBUFS; 1468 } 1469 1470 if (q->offload) { 1471 htb_set_lockdep_class_child(new); 1472 /* One ref for cl->leaf.q, the other for dev_queue->qdisc. */ 1473 qdisc_refcount_inc(new); 1474 old_q = htb_graft_helper(dev_queue, new); 1475 } 1476 1477 *old = qdisc_replace(sch, new, &cl->leaf.q); 1478 1479 if (q->offload) { 1480 WARN_ON(old_q != *old); 1481 qdisc_put(old_q); 1482 } 1483 1484 return 0; 1485} 1486 1487static struct Qdisc *htb_leaf(struct Qdisc *sch, unsigned long arg) 1488{ 1489 struct htb_class *cl = (struct htb_class *)arg; 1490 return !cl->level ? cl->leaf.q : NULL; 1491} 1492 1493static void htb_qlen_notify(struct Qdisc *sch, unsigned long arg) 1494{ 1495 struct htb_class *cl = (struct htb_class *)arg; 1496 1497 htb_deactivate(qdisc_priv(sch), cl); 1498} 1499 1500static inline int htb_parent_last_child(struct htb_class *cl) 1501{ 1502 if (!cl->parent) 1503 /* the root class */ 1504 return 0; 1505 if (cl->parent->children > 1) 1506 /* not the last child */ 1507 return 0; 1508 return 1; 1509} 1510 1511static void htb_parent_to_leaf(struct Qdisc *sch, struct htb_class *cl, 1512 struct Qdisc *new_q) 1513{ 1514 struct htb_sched *q = qdisc_priv(sch); 1515 struct htb_class *parent = cl->parent; 1516 1517 WARN_ON(cl->level || !cl->leaf.q || cl->prio_activity); 1518 1519 if (parent->cmode != HTB_CAN_SEND) 1520 htb_safe_rb_erase(&parent->pq_node, 1521 &q->hlevel[parent->level].wait_pq); 1522 1523 parent->level = 0; 1524 memset(&parent->inner, 0, sizeof(parent->inner)); 1525 parent->leaf.q = new_q ? new_q : &noop_qdisc; 1526 parent->tokens = parent->buffer; 1527 parent->ctokens = parent->cbuffer; 1528 parent->t_c = ktime_get_ns(); 1529 parent->cmode = HTB_CAN_SEND; 1530 if (q->offload) 1531 parent->leaf.offload_queue = cl->leaf.offload_queue; 1532} 1533 1534static void htb_parent_to_leaf_offload(struct Qdisc *sch, 1535 struct netdev_queue *dev_queue, 1536 struct Qdisc *new_q) 1537{ 1538 struct Qdisc *old_q; 1539 1540 /* One ref for cl->leaf.q, the other for dev_queue->qdisc. */ 1541 if (new_q) 1542 qdisc_refcount_inc(new_q); 1543 old_q = htb_graft_helper(dev_queue, new_q); 1544 WARN_ON(!(old_q->flags & TCQ_F_BUILTIN)); 1545} 1546 1547static int htb_destroy_class_offload(struct Qdisc *sch, struct htb_class *cl, 1548 bool last_child, bool destroying, 1549 struct netlink_ext_ack *extack) 1550{ 1551 struct tc_htb_qopt_offload offload_opt; 1552 struct netdev_queue *dev_queue; 1553 struct Qdisc *q = cl->leaf.q; 1554 struct Qdisc *old; 1555 int err; 1556 1557 if (cl->level) 1558 return -EINVAL; 1559 1560 WARN_ON(!q); 1561 dev_queue = htb_offload_get_queue(cl); 1562 /* When destroying, caller qdisc_graft grafts the new qdisc and invokes 1563 * qdisc_put for the qdisc being destroyed. htb_destroy_class_offload 1564 * does not need to graft or qdisc_put the qdisc being destroyed. 1565 */ 1566 if (!destroying) { 1567 old = htb_graft_helper(dev_queue, NULL); 1568 /* Last qdisc grafted should be the same as cl->leaf.q when 1569 * calling htb_delete. 1570 */ 1571 WARN_ON(old != q); 1572 } 1573 1574 if (cl->parent) { 1575 _bstats_update(&cl->parent->bstats_bias, 1576 u64_stats_read(&q->bstats.bytes), 1577 u64_stats_read(&q->bstats.packets)); 1578 } 1579 1580 offload_opt = (struct tc_htb_qopt_offload) { 1581 .command = !last_child ? TC_HTB_LEAF_DEL : 1582 destroying ? TC_HTB_LEAF_DEL_LAST_FORCE : 1583 TC_HTB_LEAF_DEL_LAST, 1584 .classid = cl->common.classid, 1585 .extack = extack, 1586 }; 1587 err = htb_offload(qdisc_dev(sch), &offload_opt); 1588 1589 if (!destroying) { 1590 if (!err) 1591 qdisc_put(old); 1592 else 1593 htb_graft_helper(dev_queue, old); 1594 } 1595 1596 if (last_child) 1597 return err; 1598 1599 if (!err && offload_opt.classid != TC_H_MIN(cl->common.classid)) { 1600 u32 classid = TC_H_MAJ(sch->handle) | 1601 TC_H_MIN(offload_opt.classid); 1602 struct htb_class *moved_cl = htb_find(classid, sch); 1603 1604 htb_offload_move_qdisc(sch, moved_cl, cl, destroying); 1605 } 1606 1607 return err; 1608} 1609 1610static void htb_destroy_class(struct Qdisc *sch, struct htb_class *cl) 1611{ 1612 if (!cl->level) { 1613 WARN_ON(!cl->leaf.q); 1614 qdisc_put(cl->leaf.q); 1615 } 1616 gen_kill_estimator(&cl->rate_est); 1617 tcf_block_put(cl->block); 1618 kfree(cl); 1619} 1620 1621static void htb_destroy(struct Qdisc *sch) 1622{ 1623 struct net_device *dev = qdisc_dev(sch); 1624 struct tc_htb_qopt_offload offload_opt; 1625 struct htb_sched *q = qdisc_priv(sch); 1626 struct hlist_node *next; 1627 bool nonempty, changed; 1628 struct htb_class *cl; 1629 unsigned int i; 1630 1631 cancel_work_sync(&q->work); 1632 qdisc_watchdog_cancel(&q->watchdog); 1633 /* This line used to be after htb_destroy_class call below 1634 * and surprisingly it worked in 2.4. But it must precede it 1635 * because filter need its target class alive to be able to call 1636 * unbind_filter on it (without Oops). 1637 */ 1638 tcf_block_put(q->block); 1639 1640 for (i = 0; i < q->clhash.hashsize; i++) { 1641 hlist_for_each_entry(cl, &q->clhash.hash[i], common.hnode) { 1642 tcf_block_put(cl->block); 1643 cl->block = NULL; 1644 } 1645 } 1646 1647 do { 1648 nonempty = false; 1649 changed = false; 1650 for (i = 0; i < q->clhash.hashsize; i++) { 1651 hlist_for_each_entry_safe(cl, next, &q->clhash.hash[i], 1652 common.hnode) { 1653 bool last_child; 1654 1655 if (!q->offload) { 1656 htb_destroy_class(sch, cl); 1657 continue; 1658 } 1659 1660 nonempty = true; 1661 1662 if (cl->level) 1663 continue; 1664 1665 changed = true; 1666 1667 last_child = htb_parent_last_child(cl); 1668 htb_destroy_class_offload(sch, cl, last_child, 1669 true, NULL); 1670 qdisc_class_hash_remove(&q->clhash, 1671 &cl->common); 1672 if (cl->parent) 1673 cl->parent->children--; 1674 if (last_child) 1675 htb_parent_to_leaf(sch, cl, NULL); 1676 htb_destroy_class(sch, cl); 1677 } 1678 } 1679 } while (changed); 1680 WARN_ON(nonempty); 1681 1682 qdisc_class_hash_destroy(&q->clhash); 1683 __qdisc_reset_queue(&q->direct_queue); 1684 1685 if (q->offload) { 1686 offload_opt = (struct tc_htb_qopt_offload) { 1687 .command = TC_HTB_DESTROY, 1688 }; 1689 htb_offload(dev, &offload_opt); 1690 } 1691 1692 if (!q->direct_qdiscs) 1693 return; 1694 for (i = 0; i < q->num_direct_qdiscs && q->direct_qdiscs[i]; i++) 1695 qdisc_put(q->direct_qdiscs[i]); 1696 kfree(q->direct_qdiscs); 1697} 1698 1699static int htb_delete(struct Qdisc *sch, unsigned long arg, 1700 struct netlink_ext_ack *extack) 1701{ 1702 struct htb_sched *q = qdisc_priv(sch); 1703 struct htb_class *cl = (struct htb_class *)arg; 1704 struct Qdisc *new_q = NULL; 1705 int last_child = 0; 1706 int err; 1707 1708 /* TODO: why don't allow to delete subtree ? references ? does 1709 * tc subsys guarantee us that in htb_destroy it holds no class 1710 * refs so that we can remove children safely there ? 1711 */ 1712 if (cl->children || qdisc_class_in_use(&cl->common)) { 1713 NL_SET_ERR_MSG(extack, "HTB class in use"); 1714 return -EBUSY; 1715 } 1716 1717 if (!cl->level && htb_parent_last_child(cl)) 1718 last_child = 1; 1719 1720 if (q->offload) { 1721 err = htb_destroy_class_offload(sch, cl, last_child, false, 1722 extack); 1723 if (err) 1724 return err; 1725 } 1726 1727 if (last_child) { 1728 struct netdev_queue *dev_queue = sch->dev_queue; 1729 1730 if (q->offload) 1731 dev_queue = htb_offload_get_queue(cl); 1732 1733 new_q = qdisc_create_dflt(dev_queue, &pfifo_qdisc_ops, 1734 cl->parent->common.classid, 1735 NULL); 1736 if (q->offload) { 1737 if (new_q) 1738 htb_set_lockdep_class_child(new_q); 1739 htb_parent_to_leaf_offload(sch, dev_queue, new_q); 1740 } 1741 } 1742 1743 sch_tree_lock(sch); 1744 1745 if (!cl->level) 1746 qdisc_purge_queue(cl->leaf.q); 1747 1748 /* delete from hash and active; remainder in destroy_class */ 1749 qdisc_class_hash_remove(&q->clhash, &cl->common); 1750 if (cl->parent) 1751 cl->parent->children--; 1752 1753 if (cl->prio_activity) 1754 htb_deactivate(q, cl); 1755 1756 if (cl->cmode != HTB_CAN_SEND) 1757 htb_safe_rb_erase(&cl->pq_node, 1758 &q->hlevel[cl->level].wait_pq); 1759 1760 if (last_child) 1761 htb_parent_to_leaf(sch, cl, new_q); 1762 1763 sch_tree_unlock(sch); 1764 1765 htb_destroy_class(sch, cl); 1766 return 0; 1767} 1768 1769static int htb_change_class(struct Qdisc *sch, u32 classid, 1770 u32 parentid, struct nlattr **tca, 1771 unsigned long *arg, struct netlink_ext_ack *extack) 1772{ 1773 int err = -EINVAL; 1774 struct htb_sched *q = qdisc_priv(sch); 1775 struct htb_class *cl = (struct htb_class *)*arg, *parent; 1776 struct tc_htb_qopt_offload offload_opt; 1777 struct nlattr *opt = tca[TCA_OPTIONS]; 1778 struct nlattr *tb[TCA_HTB_MAX + 1]; 1779 struct Qdisc *parent_qdisc = NULL; 1780 struct netdev_queue *dev_queue; 1781 struct tc_htb_opt *hopt; 1782 u64 rate64, ceil64; 1783 int warn = 0; 1784 1785 /* extract all subattrs from opt attr */ 1786 if (!opt) 1787 goto failure; 1788 1789 err = nla_parse_nested_deprecated(tb, TCA_HTB_MAX, opt, htb_policy, 1790 extack); 1791 if (err < 0) 1792 goto failure; 1793 1794 err = -EINVAL; 1795 if (tb[TCA_HTB_PARMS] == NULL) 1796 goto failure; 1797 1798 parent = parentid == TC_H_ROOT ? NULL : htb_find(parentid, sch); 1799 1800 hopt = nla_data(tb[TCA_HTB_PARMS]); 1801 if (!hopt->rate.rate || !hopt->ceil.rate) 1802 goto failure; 1803 1804 if (q->offload) { 1805 /* Options not supported by the offload. */ 1806 if (hopt->rate.overhead || hopt->ceil.overhead) { 1807 NL_SET_ERR_MSG(extack, "HTB offload doesn't support the overhead parameter"); 1808 goto failure; 1809 } 1810 if (hopt->rate.mpu || hopt->ceil.mpu) { 1811 NL_SET_ERR_MSG(extack, "HTB offload doesn't support the mpu parameter"); 1812 goto failure; 1813 } 1814 } 1815 1816 /* Keeping backward compatible with rate_table based iproute2 tc */ 1817 if (hopt->rate.linklayer == TC_LINKLAYER_UNAWARE) 1818 qdisc_put_rtab(qdisc_get_rtab(&hopt->rate, tb[TCA_HTB_RTAB], 1819 NULL)); 1820 1821 if (hopt->ceil.linklayer == TC_LINKLAYER_UNAWARE) 1822 qdisc_put_rtab(qdisc_get_rtab(&hopt->ceil, tb[TCA_HTB_CTAB], 1823 NULL)); 1824 1825 rate64 = tb[TCA_HTB_RATE64] ? nla_get_u64(tb[TCA_HTB_RATE64]) : 0; 1826 ceil64 = tb[TCA_HTB_CEIL64] ? nla_get_u64(tb[TCA_HTB_CEIL64]) : 0; 1827 1828 if (!cl) { /* new class */ 1829 struct net_device *dev = qdisc_dev(sch); 1830 struct Qdisc *new_q, *old_q; 1831 int prio; 1832 struct { 1833 struct nlattr nla; 1834 struct gnet_estimator opt; 1835 } est = { 1836 .nla = { 1837 .nla_len = nla_attr_size(sizeof(est.opt)), 1838 .nla_type = TCA_RATE, 1839 }, 1840 .opt = { 1841 /* 4s interval, 16s averaging constant */ 1842 .interval = 2, 1843 .ewma_log = 2, 1844 }, 1845 }; 1846 1847 /* check for valid classid */ 1848 if (!classid || TC_H_MAJ(classid ^ sch->handle) || 1849 htb_find(classid, sch)) 1850 goto failure; 1851 1852 /* check maximal depth */ 1853 if (parent && parent->parent && parent->parent->level < 2) { 1854 NL_SET_ERR_MSG_MOD(extack, "tree is too deep"); 1855 goto failure; 1856 } 1857 err = -ENOBUFS; 1858 cl = kzalloc(sizeof(*cl), GFP_KERNEL); 1859 if (!cl) 1860 goto failure; 1861 1862 gnet_stats_basic_sync_init(&cl->bstats); 1863 gnet_stats_basic_sync_init(&cl->bstats_bias); 1864 1865 err = tcf_block_get(&cl->block, &cl->filter_list, sch, extack); 1866 if (err) { 1867 kfree(cl); 1868 goto failure; 1869 } 1870 if (htb_rate_est || tca[TCA_RATE]) { 1871 err = gen_new_estimator(&cl->bstats, NULL, 1872 &cl->rate_est, 1873 NULL, 1874 true, 1875 tca[TCA_RATE] ? : &est.nla); 1876 if (err) 1877 goto err_block_put; 1878 } 1879 1880 cl->children = 0; 1881 RB_CLEAR_NODE(&cl->pq_node); 1882 1883 for (prio = 0; prio < TC_HTB_NUMPRIO; prio++) 1884 RB_CLEAR_NODE(&cl->node[prio]); 1885 1886 cl->common.classid = classid; 1887 1888 /* Make sure nothing interrupts us in between of two 1889 * ndo_setup_tc calls. 1890 */ 1891 ASSERT_RTNL(); 1892 1893 /* create leaf qdisc early because it uses kmalloc(GFP_KERNEL) 1894 * so that can't be used inside of sch_tree_lock 1895 * -- thanks to Karlis Peisenieks 1896 */ 1897 if (!q->offload) { 1898 dev_queue = sch->dev_queue; 1899 } else if (!(parent && !parent->level)) { 1900 /* Assign a dev_queue to this classid. */ 1901 offload_opt = (struct tc_htb_qopt_offload) { 1902 .command = TC_HTB_LEAF_ALLOC_QUEUE, 1903 .classid = cl->common.classid, 1904 .parent_classid = parent ? 1905 TC_H_MIN(parent->common.classid) : 1906 TC_HTB_CLASSID_ROOT, 1907 .rate = max_t(u64, hopt->rate.rate, rate64), 1908 .ceil = max_t(u64, hopt->ceil.rate, ceil64), 1909 .prio = hopt->prio, 1910 .quantum = hopt->quantum, 1911 .extack = extack, 1912 }; 1913 err = htb_offload(dev, &offload_opt); 1914 if (err) { 1915 NL_SET_ERR_MSG_WEAK(extack, 1916 "Failed to offload TC_HTB_LEAF_ALLOC_QUEUE"); 1917 goto err_kill_estimator; 1918 } 1919 dev_queue = netdev_get_tx_queue(dev, offload_opt.qid); 1920 } else { /* First child. */ 1921 dev_queue = htb_offload_get_queue(parent); 1922 old_q = htb_graft_helper(dev_queue, NULL); 1923 WARN_ON(old_q != parent->leaf.q); 1924 offload_opt = (struct tc_htb_qopt_offload) { 1925 .command = TC_HTB_LEAF_TO_INNER, 1926 .classid = cl->common.classid, 1927 .parent_classid = 1928 TC_H_MIN(parent->common.classid), 1929 .rate = max_t(u64, hopt->rate.rate, rate64), 1930 .ceil = max_t(u64, hopt->ceil.rate, ceil64), 1931 .prio = hopt->prio, 1932 .quantum = hopt->quantum, 1933 .extack = extack, 1934 }; 1935 err = htb_offload(dev, &offload_opt); 1936 if (err) { 1937 NL_SET_ERR_MSG_WEAK(extack, 1938 "Failed to offload TC_HTB_LEAF_TO_INNER"); 1939 htb_graft_helper(dev_queue, old_q); 1940 goto err_kill_estimator; 1941 } 1942 _bstats_update(&parent->bstats_bias, 1943 u64_stats_read(&old_q->bstats.bytes), 1944 u64_stats_read(&old_q->bstats.packets)); 1945 qdisc_put(old_q); 1946 } 1947 new_q = qdisc_create_dflt(dev_queue, &pfifo_qdisc_ops, 1948 classid, NULL); 1949 if (q->offload) { 1950 if (new_q) { 1951 htb_set_lockdep_class_child(new_q); 1952 /* One ref for cl->leaf.q, the other for 1953 * dev_queue->qdisc. 1954 */ 1955 qdisc_refcount_inc(new_q); 1956 } 1957 old_q = htb_graft_helper(dev_queue, new_q); 1958 /* No qdisc_put needed. */ 1959 WARN_ON(!(old_q->flags & TCQ_F_BUILTIN)); 1960 } 1961 sch_tree_lock(sch); 1962 if (parent && !parent->level) { 1963 /* turn parent into inner node */ 1964 qdisc_purge_queue(parent->leaf.q); 1965 parent_qdisc = parent->leaf.q; 1966 if (parent->prio_activity) 1967 htb_deactivate(q, parent); 1968 1969 /* remove from evt list because of level change */ 1970 if (parent->cmode != HTB_CAN_SEND) { 1971 htb_safe_rb_erase(&parent->pq_node, &q->hlevel[0].wait_pq); 1972 parent->cmode = HTB_CAN_SEND; 1973 } 1974 parent->level = (parent->parent ? parent->parent->level 1975 : TC_HTB_MAXDEPTH) - 1; 1976 memset(&parent->inner, 0, sizeof(parent->inner)); 1977 } 1978 1979 /* leaf (we) needs elementary qdisc */ 1980 cl->leaf.q = new_q ? new_q : &noop_qdisc; 1981 if (q->offload) 1982 cl->leaf.offload_queue = dev_queue; 1983 1984 cl->parent = parent; 1985 1986 /* set class to be in HTB_CAN_SEND state */ 1987 cl->tokens = PSCHED_TICKS2NS(hopt->buffer); 1988 cl->ctokens = PSCHED_TICKS2NS(hopt->cbuffer); 1989 cl->mbuffer = 60ULL * NSEC_PER_SEC; /* 1min */ 1990 cl->t_c = ktime_get_ns(); 1991 cl->cmode = HTB_CAN_SEND; 1992 1993 /* attach to the hash list and parent's family */ 1994 qdisc_class_hash_insert(&q->clhash, &cl->common); 1995 if (parent) 1996 parent->children++; 1997 if (cl->leaf.q != &noop_qdisc) 1998 qdisc_hash_add(cl->leaf.q, true); 1999 } else { 2000 if (tca[TCA_RATE]) { 2001 err = gen_replace_estimator(&cl->bstats, NULL, 2002 &cl->rate_est, 2003 NULL, 2004 true, 2005 tca[TCA_RATE]); 2006 if (err) 2007 return err; 2008 } 2009 2010 if (q->offload) { 2011 struct net_device *dev = qdisc_dev(sch); 2012 2013 offload_opt = (struct tc_htb_qopt_offload) { 2014 .command = TC_HTB_NODE_MODIFY, 2015 .classid = cl->common.classid, 2016 .rate = max_t(u64, hopt->rate.rate, rate64), 2017 .ceil = max_t(u64, hopt->ceil.rate, ceil64), 2018 .prio = hopt->prio, 2019 .quantum = hopt->quantum, 2020 .extack = extack, 2021 }; 2022 err = htb_offload(dev, &offload_opt); 2023 if (err) 2024 /* Estimator was replaced, and rollback may fail 2025 * as well, so we don't try to recover it, and 2026 * the estimator won't work property with the 2027 * offload anyway, because bstats are updated 2028 * only when the stats are queried. 2029 */ 2030 return err; 2031 } 2032 2033 sch_tree_lock(sch); 2034 } 2035 2036 psched_ratecfg_precompute(&cl->rate, &hopt->rate, rate64); 2037 psched_ratecfg_precompute(&cl->ceil, &hopt->ceil, ceil64); 2038 2039 /* it used to be a nasty bug here, we have to check that node 2040 * is really leaf before changing cl->leaf ! 2041 */ 2042 if (!cl->level) { 2043 u64 quantum = cl->rate.rate_bytes_ps; 2044 2045 do_div(quantum, q->rate2quantum); 2046 cl->quantum = min_t(u64, quantum, INT_MAX); 2047 2048 if (!hopt->quantum && cl->quantum < 1000) { 2049 warn = -1; 2050 cl->quantum = 1000; 2051 } 2052 if (!hopt->quantum && cl->quantum > 200000) { 2053 warn = 1; 2054 cl->quantum = 200000; 2055 } 2056 if (hopt->quantum) 2057 cl->quantum = hopt->quantum; 2058 if ((cl->prio = hopt->prio) >= TC_HTB_NUMPRIO) 2059 cl->prio = TC_HTB_NUMPRIO - 1; 2060 } 2061 2062 cl->buffer = PSCHED_TICKS2NS(hopt->buffer); 2063 cl->cbuffer = PSCHED_TICKS2NS(hopt->cbuffer); 2064 2065 sch_tree_unlock(sch); 2066 qdisc_put(parent_qdisc); 2067 2068 if (warn) 2069 NL_SET_ERR_MSG_FMT_MOD(extack, 2070 "quantum of class %X is %s. Consider r2q change.", 2071 cl->common.classid, (warn == -1 ? "small" : "big")); 2072 2073 qdisc_class_hash_grow(sch, &q->clhash); 2074 2075 *arg = (unsigned long)cl; 2076 return 0; 2077 2078err_kill_estimator: 2079 gen_kill_estimator(&cl->rate_est); 2080err_block_put: 2081 tcf_block_put(cl->block); 2082 kfree(cl); 2083failure: 2084 return err; 2085} 2086 2087static struct tcf_block *htb_tcf_block(struct Qdisc *sch, unsigned long arg, 2088 struct netlink_ext_ack *extack) 2089{ 2090 struct htb_sched *q = qdisc_priv(sch); 2091 struct htb_class *cl = (struct htb_class *)arg; 2092 2093 return cl ? cl->block : q->block; 2094} 2095 2096static unsigned long htb_bind_filter(struct Qdisc *sch, unsigned long parent, 2097 u32 classid) 2098{ 2099 struct htb_class *cl = htb_find(classid, sch); 2100 2101 /*if (cl && !cl->level) return 0; 2102 * The line above used to be there to prevent attaching filters to 2103 * leaves. But at least tc_index filter uses this just to get class 2104 * for other reasons so that we have to allow for it. 2105 * ---- 2106 * 19.6.2002 As Werner explained it is ok - bind filter is just 2107 * another way to "lock" the class - unlike "get" this lock can 2108 * be broken by class during destroy IIUC. 2109 */ 2110 if (cl) 2111 qdisc_class_get(&cl->common); 2112 return (unsigned long)cl; 2113} 2114 2115static void htb_unbind_filter(struct Qdisc *sch, unsigned long arg) 2116{ 2117 struct htb_class *cl = (struct htb_class *)arg; 2118 2119 qdisc_class_put(&cl->common); 2120} 2121 2122static void htb_walk(struct Qdisc *sch, struct qdisc_walker *arg) 2123{ 2124 struct htb_sched *q = qdisc_priv(sch); 2125 struct htb_class *cl; 2126 unsigned int i; 2127 2128 if (arg->stop) 2129 return; 2130 2131 for (i = 0; i < q->clhash.hashsize; i++) { 2132 hlist_for_each_entry(cl, &q->clhash.hash[i], common.hnode) { 2133 if (!tc_qdisc_stats_dump(sch, (unsigned long)cl, arg)) 2134 return; 2135 } 2136 } 2137} 2138 2139static const struct Qdisc_class_ops htb_class_ops = { 2140 .select_queue = htb_select_queue, 2141 .graft = htb_graft, 2142 .leaf = htb_leaf, 2143 .qlen_notify = htb_qlen_notify, 2144 .find = htb_search, 2145 .change = htb_change_class, 2146 .delete = htb_delete, 2147 .walk = htb_walk, 2148 .tcf_block = htb_tcf_block, 2149 .bind_tcf = htb_bind_filter, 2150 .unbind_tcf = htb_unbind_filter, 2151 .dump = htb_dump_class, 2152 .dump_stats = htb_dump_class_stats, 2153}; 2154 2155static struct Qdisc_ops htb_qdisc_ops __read_mostly = { 2156 .cl_ops = &htb_class_ops, 2157 .id = "htb", 2158 .priv_size = sizeof(struct htb_sched), 2159 .enqueue = htb_enqueue, 2160 .dequeue = htb_dequeue, 2161 .peek = qdisc_peek_dequeued, 2162 .init = htb_init, 2163 .attach = htb_attach, 2164 .reset = htb_reset, 2165 .destroy = htb_destroy, 2166 .dump = htb_dump, 2167 .owner = THIS_MODULE, 2168}; 2169MODULE_ALIAS_NET_SCH("htb"); 2170 2171static int __init htb_module_init(void) 2172{ 2173 return register_qdisc(&htb_qdisc_ops); 2174} 2175static void __exit htb_module_exit(void) 2176{ 2177 unregister_qdisc(&htb_qdisc_ops); 2178} 2179 2180module_init(htb_module_init) 2181module_exit(htb_module_exit) 2182MODULE_LICENSE("GPL"); 2183MODULE_DESCRIPTION("Hierarchical Token Bucket scheduler"); 2184