1 #ifndef __NET_SCHED_GENERIC_H 2 #define __NET_SCHED_GENERIC_H 3 4 #include <linux/netdevice.h> 5 #include <linux/types.h> 6 #include <linux/rcupdate.h> 7 #include <linux/pkt_sched.h> 8 #include <linux/pkt_cls.h> 9 #include <linux/percpu.h> 10 #include <linux/dynamic_queue_limits.h> 11 #include <net/gen_stats.h> 12 #include <net/rtnetlink.h> 13 14 struct Qdisc_ops; 15 struct qdisc_walker; 16 struct tcf_walker; 17 struct module; 18 19 struct qdisc_rate_table { 20 struct tc_ratespec rate; 21 u32 data[256]; 22 struct qdisc_rate_table *next; 23 int refcnt; 24 }; 25 26 enum qdisc_state_t { 27 __QDISC_STATE_SCHED, 28 __QDISC_STATE_DEACTIVATED, 29 }; 30 31 struct qdisc_size_table { 32 struct rcu_head rcu; 33 struct list_head list; 34 struct tc_sizespec szopts; 35 int refcnt; 36 u16 data[]; 37 }; 38 39 struct Qdisc { 40 int (*enqueue)(struct sk_buff *skb, 41 struct Qdisc *sch, 42 struct sk_buff **to_free); 43 struct sk_buff * (*dequeue)(struct Qdisc *sch); 44 unsigned int flags; 45 #define TCQ_F_BUILTIN 1 46 #define TCQ_F_INGRESS 2 47 #define TCQ_F_CAN_BYPASS 4 48 #define TCQ_F_MQROOT 8 49 #define TCQ_F_ONETXQUEUE 0x10 /* dequeue_skb() can assume all skbs are for 50 * q->dev_queue : It can test 51 * netif_xmit_frozen_or_stopped() before 52 * dequeueing next packet. 53 * Its true for MQ/MQPRIO slaves, or non 54 * multiqueue device. 55 */ 56 #define TCQ_F_WARN_NONWC (1 << 16) 57 #define TCQ_F_CPUSTATS 0x20 /* run using percpu statistics */ 58 #define TCQ_F_NOPARENT 0x40 /* root of its hierarchy : 59 * qdisc_tree_decrease_qlen() should stop. 60 */ 61 u32 limit; 62 const struct Qdisc_ops *ops; 63 struct qdisc_size_table __rcu *stab; 64 struct list_head list; 65 u32 handle; 66 u32 parent; 67 void *u32_node; 68 69 struct netdev_queue *dev_queue; 70 71 struct gnet_stats_rate_est64 rate_est; 72 struct gnet_stats_basic_cpu __percpu *cpu_bstats; 73 struct gnet_stats_queue __percpu *cpu_qstats; 74 75 /* 76 * For performance sake on SMP, we put highly modified fields at the end 77 */ 78 struct sk_buff *gso_skb ____cacheline_aligned_in_smp; 79 struct sk_buff_head q; 80 struct gnet_stats_basic_packed bstats; 81 seqcount_t running; 82 struct gnet_stats_queue qstats; 83 unsigned long state; 84 struct Qdisc *next_sched; 85 struct sk_buff *skb_bad_txq; 86 struct rcu_head rcu_head; 87 int padded; 88 atomic_t refcnt; 89 90 spinlock_t busylock ____cacheline_aligned_in_smp; 91 }; 92 93 static inline bool qdisc_is_running(const struct Qdisc *qdisc) 94 { 95 return (raw_read_seqcount(&qdisc->running) & 1) ? true : false; 96 } 97 98 static inline bool qdisc_run_begin(struct Qdisc *qdisc) 99 { 100 if (qdisc_is_running(qdisc)) 101 return false; 102 /* Variant of write_seqcount_begin() telling lockdep a trylock 103 * was attempted. 104 */ 105 raw_write_seqcount_begin(&qdisc->running); 106 seqcount_acquire(&qdisc->running.dep_map, 0, 1, _RET_IP_); 107 return true; 108 } 109 110 static inline void qdisc_run_end(struct Qdisc *qdisc) 111 { 112 write_seqcount_end(&qdisc->running); 113 } 114 115 static inline bool qdisc_may_bulk(const struct Qdisc *qdisc) 116 { 117 return qdisc->flags & TCQ_F_ONETXQUEUE; 118 } 119 120 static inline int qdisc_avail_bulklimit(const struct netdev_queue *txq) 121 { 122 #ifdef CONFIG_BQL 123 /* Non-BQL migrated drivers will return 0, too. */ 124 return dql_avail(&txq->dql); 125 #else 126 return 0; 127 #endif 128 } 129 130 struct Qdisc_class_ops { 131 /* Child qdisc manipulation */ 132 struct netdev_queue * (*select_queue)(struct Qdisc *, struct tcmsg *); 133 int (*graft)(struct Qdisc *, unsigned long cl, 134 struct Qdisc *, struct Qdisc **); 135 struct Qdisc * (*leaf)(struct Qdisc *, unsigned long cl); 136 void (*qlen_notify)(struct Qdisc *, unsigned long); 137 138 /* Class manipulation routines */ 139 unsigned long (*get)(struct Qdisc *, u32 classid); 140 void (*put)(struct Qdisc *, unsigned long); 141 int (*change)(struct Qdisc *, u32, u32, 142 struct nlattr **, unsigned long *); 143 int (*delete)(struct Qdisc *, unsigned long); 144 void (*walk)(struct Qdisc *, struct qdisc_walker * arg); 145 146 /* Filter manipulation */ 147 struct tcf_proto __rcu ** (*tcf_chain)(struct Qdisc *, unsigned long); 148 bool (*tcf_cl_offload)(u32 classid); 149 unsigned long (*bind_tcf)(struct Qdisc *, unsigned long, 150 u32 classid); 151 void (*unbind_tcf)(struct Qdisc *, unsigned long); 152 153 /* rtnetlink specific */ 154 int (*dump)(struct Qdisc *, unsigned long, 155 struct sk_buff *skb, struct tcmsg*); 156 int (*dump_stats)(struct Qdisc *, unsigned long, 157 struct gnet_dump *); 158 }; 159 160 struct Qdisc_ops { 161 struct Qdisc_ops *next; 162 const struct Qdisc_class_ops *cl_ops; 163 char id[IFNAMSIZ]; 164 int priv_size; 165 166 int (*enqueue)(struct sk_buff *skb, 167 struct Qdisc *sch, 168 struct sk_buff **to_free); 169 struct sk_buff * (*dequeue)(struct Qdisc *); 170 struct sk_buff * (*peek)(struct Qdisc *); 171 172 int (*init)(struct Qdisc *, struct nlattr *arg); 173 void (*reset)(struct Qdisc *); 174 void (*destroy)(struct Qdisc *); 175 int (*change)(struct Qdisc *, struct nlattr *arg); 176 void (*attach)(struct Qdisc *); 177 178 int (*dump)(struct Qdisc *, struct sk_buff *); 179 int (*dump_stats)(struct Qdisc *, struct gnet_dump *); 180 181 struct module *owner; 182 }; 183 184 185 struct tcf_result { 186 unsigned long class; 187 u32 classid; 188 }; 189 190 struct tcf_proto_ops { 191 struct list_head head; 192 char kind[IFNAMSIZ]; 193 194 int (*classify)(struct sk_buff *, 195 const struct tcf_proto *, 196 struct tcf_result *); 197 int (*init)(struct tcf_proto*); 198 bool (*destroy)(struct tcf_proto*, bool); 199 200 unsigned long (*get)(struct tcf_proto*, u32 handle); 201 int (*change)(struct net *net, struct sk_buff *, 202 struct tcf_proto*, unsigned long, 203 u32 handle, struct nlattr **, 204 unsigned long *, bool); 205 int (*delete)(struct tcf_proto*, unsigned long); 206 void (*walk)(struct tcf_proto*, struct tcf_walker *arg); 207 208 /* rtnetlink specific */ 209 int (*dump)(struct net*, struct tcf_proto*, unsigned long, 210 struct sk_buff *skb, struct tcmsg*); 211 212 struct module *owner; 213 }; 214 215 struct tcf_proto { 216 /* Fast access part */ 217 struct tcf_proto __rcu *next; 218 void __rcu *root; 219 int (*classify)(struct sk_buff *, 220 const struct tcf_proto *, 221 struct tcf_result *); 222 __be16 protocol; 223 224 /* All the rest */ 225 u32 prio; 226 u32 classid; 227 struct Qdisc *q; 228 void *data; 229 const struct tcf_proto_ops *ops; 230 struct rcu_head rcu; 231 }; 232 233 struct qdisc_skb_cb { 234 unsigned int pkt_len; 235 u16 slave_dev_queue_mapping; 236 u16 tc_classid; 237 #define QDISC_CB_PRIV_LEN 20 238 unsigned char data[QDISC_CB_PRIV_LEN]; 239 }; 240 241 static inline void qdisc_cb_private_validate(const struct sk_buff *skb, int sz) 242 { 243 struct qdisc_skb_cb *qcb; 244 245 BUILD_BUG_ON(sizeof(skb->cb) < offsetof(struct qdisc_skb_cb, data) + sz); 246 BUILD_BUG_ON(sizeof(qcb->data) < sz); 247 } 248 249 static inline int qdisc_qlen(const struct Qdisc *q) 250 { 251 return q->q.qlen; 252 } 253 254 static inline struct qdisc_skb_cb *qdisc_skb_cb(const struct sk_buff *skb) 255 { 256 return (struct qdisc_skb_cb *)skb->cb; 257 } 258 259 static inline spinlock_t *qdisc_lock(struct Qdisc *qdisc) 260 { 261 return &qdisc->q.lock; 262 } 263 264 static inline struct Qdisc *qdisc_root(const struct Qdisc *qdisc) 265 { 266 struct Qdisc *q = rcu_dereference_rtnl(qdisc->dev_queue->qdisc); 267 268 return q; 269 } 270 271 static inline struct Qdisc *qdisc_root_sleeping(const struct Qdisc *qdisc) 272 { 273 return qdisc->dev_queue->qdisc_sleeping; 274 } 275 276 /* The qdisc root lock is a mechanism by which to top level 277 * of a qdisc tree can be locked from any qdisc node in the 278 * forest. This allows changing the configuration of some 279 * aspect of the qdisc tree while blocking out asynchronous 280 * qdisc access in the packet processing paths. 281 * 282 * It is only legal to do this when the root will not change 283 * on us. Otherwise we'll potentially lock the wrong qdisc 284 * root. This is enforced by holding the RTNL semaphore, which 285 * all users of this lock accessor must do. 286 */ 287 static inline spinlock_t *qdisc_root_lock(const struct Qdisc *qdisc) 288 { 289 struct Qdisc *root = qdisc_root(qdisc); 290 291 ASSERT_RTNL(); 292 return qdisc_lock(root); 293 } 294 295 static inline spinlock_t *qdisc_root_sleeping_lock(const struct Qdisc *qdisc) 296 { 297 struct Qdisc *root = qdisc_root_sleeping(qdisc); 298 299 ASSERT_RTNL(); 300 return qdisc_lock(root); 301 } 302 303 static inline seqcount_t *qdisc_root_sleeping_running(const struct Qdisc *qdisc) 304 { 305 struct Qdisc *root = qdisc_root_sleeping(qdisc); 306 307 ASSERT_RTNL(); 308 return &root->running; 309 } 310 311 static inline struct net_device *qdisc_dev(const struct Qdisc *qdisc) 312 { 313 return qdisc->dev_queue->dev; 314 } 315 316 static inline void sch_tree_lock(const struct Qdisc *q) 317 { 318 spin_lock_bh(qdisc_root_sleeping_lock(q)); 319 } 320 321 static inline void sch_tree_unlock(const struct Qdisc *q) 322 { 323 spin_unlock_bh(qdisc_root_sleeping_lock(q)); 324 } 325 326 #define tcf_tree_lock(tp) sch_tree_lock((tp)->q) 327 #define tcf_tree_unlock(tp) sch_tree_unlock((tp)->q) 328 329 extern struct Qdisc noop_qdisc; 330 extern struct Qdisc_ops noop_qdisc_ops; 331 extern struct Qdisc_ops pfifo_fast_ops; 332 extern struct Qdisc_ops mq_qdisc_ops; 333 extern struct Qdisc_ops noqueue_qdisc_ops; 334 extern const struct Qdisc_ops *default_qdisc_ops; 335 static inline const struct Qdisc_ops * 336 get_default_qdisc_ops(const struct net_device *dev, int ntx) 337 { 338 return ntx < dev->real_num_tx_queues ? 339 default_qdisc_ops : &pfifo_fast_ops; 340 } 341 342 struct Qdisc_class_common { 343 u32 classid; 344 struct hlist_node hnode; 345 }; 346 347 struct Qdisc_class_hash { 348 struct hlist_head *hash; 349 unsigned int hashsize; 350 unsigned int hashmask; 351 unsigned int hashelems; 352 }; 353 354 static inline unsigned int qdisc_class_hash(u32 id, u32 mask) 355 { 356 id ^= id >> 8; 357 id ^= id >> 4; 358 return id & mask; 359 } 360 361 static inline struct Qdisc_class_common * 362 qdisc_class_find(const struct Qdisc_class_hash *hash, u32 id) 363 { 364 struct Qdisc_class_common *cl; 365 unsigned int h; 366 367 h = qdisc_class_hash(id, hash->hashmask); 368 hlist_for_each_entry(cl, &hash->hash[h], hnode) { 369 if (cl->classid == id) 370 return cl; 371 } 372 return NULL; 373 } 374 375 int qdisc_class_hash_init(struct Qdisc_class_hash *); 376 void qdisc_class_hash_insert(struct Qdisc_class_hash *, 377 struct Qdisc_class_common *); 378 void qdisc_class_hash_remove(struct Qdisc_class_hash *, 379 struct Qdisc_class_common *); 380 void qdisc_class_hash_grow(struct Qdisc *, struct Qdisc_class_hash *); 381 void qdisc_class_hash_destroy(struct Qdisc_class_hash *); 382 383 void dev_init_scheduler(struct net_device *dev); 384 void dev_shutdown(struct net_device *dev); 385 void dev_activate(struct net_device *dev); 386 void dev_deactivate(struct net_device *dev); 387 void dev_deactivate_many(struct list_head *head); 388 struct Qdisc *dev_graft_qdisc(struct netdev_queue *dev_queue, 389 struct Qdisc *qdisc); 390 void qdisc_reset(struct Qdisc *qdisc); 391 void qdisc_destroy(struct Qdisc *qdisc); 392 void qdisc_tree_reduce_backlog(struct Qdisc *qdisc, unsigned int n, 393 unsigned int len); 394 struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue, 395 const struct Qdisc_ops *ops); 396 struct Qdisc *qdisc_create_dflt(struct netdev_queue *dev_queue, 397 const struct Qdisc_ops *ops, u32 parentid); 398 void __qdisc_calculate_pkt_len(struct sk_buff *skb, 399 const struct qdisc_size_table *stab); 400 bool tcf_destroy(struct tcf_proto *tp, bool force); 401 void tcf_destroy_chain(struct tcf_proto __rcu **fl); 402 int skb_do_redirect(struct sk_buff *); 403 404 static inline bool skb_at_tc_ingress(const struct sk_buff *skb) 405 { 406 #ifdef CONFIG_NET_CLS_ACT 407 return G_TC_AT(skb->tc_verd) & AT_INGRESS; 408 #else 409 return false; 410 #endif 411 } 412 413 /* Reset all TX qdiscs greater then index of a device. */ 414 static inline void qdisc_reset_all_tx_gt(struct net_device *dev, unsigned int i) 415 { 416 struct Qdisc *qdisc; 417 418 for (; i < dev->num_tx_queues; i++) { 419 qdisc = rtnl_dereference(netdev_get_tx_queue(dev, i)->qdisc); 420 if (qdisc) { 421 spin_lock_bh(qdisc_lock(qdisc)); 422 qdisc_reset(qdisc); 423 spin_unlock_bh(qdisc_lock(qdisc)); 424 } 425 } 426 } 427 428 static inline void qdisc_reset_all_tx(struct net_device *dev) 429 { 430 qdisc_reset_all_tx_gt(dev, 0); 431 } 432 433 /* Are all TX queues of the device empty? */ 434 static inline bool qdisc_all_tx_empty(const struct net_device *dev) 435 { 436 unsigned int i; 437 438 rcu_read_lock(); 439 for (i = 0; i < dev->num_tx_queues; i++) { 440 struct netdev_queue *txq = netdev_get_tx_queue(dev, i); 441 const struct Qdisc *q = rcu_dereference(txq->qdisc); 442 443 if (q->q.qlen) { 444 rcu_read_unlock(); 445 return false; 446 } 447 } 448 rcu_read_unlock(); 449 return true; 450 } 451 452 /* Are any of the TX qdiscs changing? */ 453 static inline bool qdisc_tx_changing(const struct net_device *dev) 454 { 455 unsigned int i; 456 457 for (i = 0; i < dev->num_tx_queues; i++) { 458 struct netdev_queue *txq = netdev_get_tx_queue(dev, i); 459 if (rcu_access_pointer(txq->qdisc) != txq->qdisc_sleeping) 460 return true; 461 } 462 return false; 463 } 464 465 /* Is the device using the noop qdisc on all queues? */ 466 static inline bool qdisc_tx_is_noop(const struct net_device *dev) 467 { 468 unsigned int i; 469 470 for (i = 0; i < dev->num_tx_queues; i++) { 471 struct netdev_queue *txq = netdev_get_tx_queue(dev, i); 472 if (rcu_access_pointer(txq->qdisc) != &noop_qdisc) 473 return false; 474 } 475 return true; 476 } 477 478 static inline unsigned int qdisc_pkt_len(const struct sk_buff *skb) 479 { 480 return qdisc_skb_cb(skb)->pkt_len; 481 } 482 483 /* additional qdisc xmit flags (NET_XMIT_MASK in linux/netdevice.h) */ 484 enum net_xmit_qdisc_t { 485 __NET_XMIT_STOLEN = 0x00010000, 486 __NET_XMIT_BYPASS = 0x00020000, 487 }; 488 489 #ifdef CONFIG_NET_CLS_ACT 490 #define net_xmit_drop_count(e) ((e) & __NET_XMIT_STOLEN ? 0 : 1) 491 #else 492 #define net_xmit_drop_count(e) (1) 493 #endif 494 495 static inline void qdisc_calculate_pkt_len(struct sk_buff *skb, 496 const struct Qdisc *sch) 497 { 498 #ifdef CONFIG_NET_SCHED 499 struct qdisc_size_table *stab = rcu_dereference_bh(sch->stab); 500 501 if (stab) 502 __qdisc_calculate_pkt_len(skb, stab); 503 #endif 504 } 505 506 static inline int qdisc_enqueue(struct sk_buff *skb, struct Qdisc *sch, 507 struct sk_buff **to_free) 508 { 509 qdisc_calculate_pkt_len(skb, sch); 510 return sch->enqueue(skb, sch, to_free); 511 } 512 513 static inline bool qdisc_is_percpu_stats(const struct Qdisc *q) 514 { 515 return q->flags & TCQ_F_CPUSTATS; 516 } 517 518 static inline void _bstats_update(struct gnet_stats_basic_packed *bstats, 519 __u64 bytes, __u32 packets) 520 { 521 bstats->bytes += bytes; 522 bstats->packets += packets; 523 } 524 525 static inline void bstats_update(struct gnet_stats_basic_packed *bstats, 526 const struct sk_buff *skb) 527 { 528 _bstats_update(bstats, 529 qdisc_pkt_len(skb), 530 skb_is_gso(skb) ? skb_shinfo(skb)->gso_segs : 1); 531 } 532 533 static inline void _bstats_cpu_update(struct gnet_stats_basic_cpu *bstats, 534 __u64 bytes, __u32 packets) 535 { 536 u64_stats_update_begin(&bstats->syncp); 537 _bstats_update(&bstats->bstats, bytes, packets); 538 u64_stats_update_end(&bstats->syncp); 539 } 540 541 static inline void bstats_cpu_update(struct gnet_stats_basic_cpu *bstats, 542 const struct sk_buff *skb) 543 { 544 u64_stats_update_begin(&bstats->syncp); 545 bstats_update(&bstats->bstats, skb); 546 u64_stats_update_end(&bstats->syncp); 547 } 548 549 static inline void qdisc_bstats_cpu_update(struct Qdisc *sch, 550 const struct sk_buff *skb) 551 { 552 bstats_cpu_update(this_cpu_ptr(sch->cpu_bstats), skb); 553 } 554 555 static inline void qdisc_bstats_update(struct Qdisc *sch, 556 const struct sk_buff *skb) 557 { 558 bstats_update(&sch->bstats, skb); 559 } 560 561 static inline void qdisc_qstats_backlog_dec(struct Qdisc *sch, 562 const struct sk_buff *skb) 563 { 564 sch->qstats.backlog -= qdisc_pkt_len(skb); 565 } 566 567 static inline void qdisc_qstats_backlog_inc(struct Qdisc *sch, 568 const struct sk_buff *skb) 569 { 570 sch->qstats.backlog += qdisc_pkt_len(skb); 571 } 572 573 static inline void __qdisc_qstats_drop(struct Qdisc *sch, int count) 574 { 575 sch->qstats.drops += count; 576 } 577 578 static inline void qstats_drop_inc(struct gnet_stats_queue *qstats) 579 { 580 qstats->drops++; 581 } 582 583 static inline void qstats_overlimit_inc(struct gnet_stats_queue *qstats) 584 { 585 qstats->overlimits++; 586 } 587 588 static inline void qdisc_qstats_drop(struct Qdisc *sch) 589 { 590 qstats_drop_inc(&sch->qstats); 591 } 592 593 static inline void qdisc_qstats_cpu_drop(struct Qdisc *sch) 594 { 595 qstats_drop_inc(this_cpu_ptr(sch->cpu_qstats)); 596 } 597 598 static inline void qdisc_qstats_overlimit(struct Qdisc *sch) 599 { 600 sch->qstats.overlimits++; 601 } 602 603 static inline int __qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch, 604 struct sk_buff_head *list) 605 { 606 __skb_queue_tail(list, skb); 607 qdisc_qstats_backlog_inc(sch, skb); 608 609 return NET_XMIT_SUCCESS; 610 } 611 612 static inline int qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch) 613 { 614 return __qdisc_enqueue_tail(skb, sch, &sch->q); 615 } 616 617 static inline struct sk_buff *__qdisc_dequeue_head(struct Qdisc *sch, 618 struct sk_buff_head *list) 619 { 620 struct sk_buff *skb = __skb_dequeue(list); 621 622 if (likely(skb != NULL)) { 623 qdisc_qstats_backlog_dec(sch, skb); 624 qdisc_bstats_update(sch, skb); 625 } 626 627 return skb; 628 } 629 630 static inline struct sk_buff *qdisc_dequeue_head(struct Qdisc *sch) 631 { 632 return __qdisc_dequeue_head(sch, &sch->q); 633 } 634 635 /* Instead of calling kfree_skb() while root qdisc lock is held, 636 * queue the skb for future freeing at end of __dev_xmit_skb() 637 */ 638 static inline void __qdisc_drop(struct sk_buff *skb, struct sk_buff **to_free) 639 { 640 skb->next = *to_free; 641 *to_free = skb; 642 } 643 644 static inline unsigned int __qdisc_queue_drop_head(struct Qdisc *sch, 645 struct sk_buff_head *list, 646 struct sk_buff **to_free) 647 { 648 struct sk_buff *skb = __skb_dequeue(list); 649 650 if (likely(skb != NULL)) { 651 unsigned int len = qdisc_pkt_len(skb); 652 653 qdisc_qstats_backlog_dec(sch, skb); 654 __qdisc_drop(skb, to_free); 655 return len; 656 } 657 658 return 0; 659 } 660 661 static inline unsigned int qdisc_queue_drop_head(struct Qdisc *sch, 662 struct sk_buff **to_free) 663 { 664 return __qdisc_queue_drop_head(sch, &sch->q, to_free); 665 } 666 667 static inline struct sk_buff *qdisc_peek_head(struct Qdisc *sch) 668 { 669 return skb_peek(&sch->q); 670 } 671 672 /* generic pseudo peek method for non-work-conserving qdisc */ 673 static inline struct sk_buff *qdisc_peek_dequeued(struct Qdisc *sch) 674 { 675 /* we can reuse ->gso_skb because peek isn't called for root qdiscs */ 676 if (!sch->gso_skb) { 677 sch->gso_skb = sch->dequeue(sch); 678 if (sch->gso_skb) { 679 /* it's still part of the queue */ 680 qdisc_qstats_backlog_inc(sch, sch->gso_skb); 681 sch->q.qlen++; 682 } 683 } 684 685 return sch->gso_skb; 686 } 687 688 /* use instead of qdisc->dequeue() for all qdiscs queried with ->peek() */ 689 static inline struct sk_buff *qdisc_dequeue_peeked(struct Qdisc *sch) 690 { 691 struct sk_buff *skb = sch->gso_skb; 692 693 if (skb) { 694 sch->gso_skb = NULL; 695 qdisc_qstats_backlog_dec(sch, skb); 696 sch->q.qlen--; 697 } else { 698 skb = sch->dequeue(sch); 699 } 700 701 return skb; 702 } 703 704 static inline void __qdisc_reset_queue(struct sk_buff_head *list) 705 { 706 /* 707 * We do not know the backlog in bytes of this list, it 708 * is up to the caller to correct it 709 */ 710 if (!skb_queue_empty(list)) { 711 rtnl_kfree_skbs(list->next, list->prev); 712 __skb_queue_head_init(list); 713 } 714 } 715 716 static inline void qdisc_reset_queue(struct Qdisc *sch) 717 { 718 __qdisc_reset_queue(&sch->q); 719 sch->qstats.backlog = 0; 720 } 721 722 static inline struct Qdisc *qdisc_replace(struct Qdisc *sch, struct Qdisc *new, 723 struct Qdisc **pold) 724 { 725 struct Qdisc *old; 726 727 sch_tree_lock(sch); 728 old = *pold; 729 *pold = new; 730 if (old != NULL) { 731 qdisc_tree_reduce_backlog(old, old->q.qlen, old->qstats.backlog); 732 qdisc_reset(old); 733 } 734 sch_tree_unlock(sch); 735 736 return old; 737 } 738 739 static inline void rtnl_qdisc_drop(struct sk_buff *skb, struct Qdisc *sch) 740 { 741 rtnl_kfree_skbs(skb, skb); 742 qdisc_qstats_drop(sch); 743 } 744 745 746 static inline int qdisc_drop(struct sk_buff *skb, struct Qdisc *sch, 747 struct sk_buff **to_free) 748 { 749 __qdisc_drop(skb, to_free); 750 qdisc_qstats_drop(sch); 751 752 return NET_XMIT_DROP; 753 } 754 755 /* Length to Time (L2T) lookup in a qdisc_rate_table, to determine how 756 long it will take to send a packet given its size. 757 */ 758 static inline u32 qdisc_l2t(struct qdisc_rate_table* rtab, unsigned int pktlen) 759 { 760 int slot = pktlen + rtab->rate.cell_align + rtab->rate.overhead; 761 if (slot < 0) 762 slot = 0; 763 slot >>= rtab->rate.cell_log; 764 if (slot > 255) 765 return rtab->data[255]*(slot >> 8) + rtab->data[slot & 0xFF]; 766 return rtab->data[slot]; 767 } 768 769 struct psched_ratecfg { 770 u64 rate_bytes_ps; /* bytes per second */ 771 u32 mult; 772 u16 overhead; 773 u8 linklayer; 774 u8 shift; 775 }; 776 777 static inline u64 psched_l2t_ns(const struct psched_ratecfg *r, 778 unsigned int len) 779 { 780 len += r->overhead; 781 782 if (unlikely(r->linklayer == TC_LINKLAYER_ATM)) 783 return ((u64)(DIV_ROUND_UP(len,48)*53) * r->mult) >> r->shift; 784 785 return ((u64)len * r->mult) >> r->shift; 786 } 787 788 void psched_ratecfg_precompute(struct psched_ratecfg *r, 789 const struct tc_ratespec *conf, 790 u64 rate64); 791 792 static inline void psched_ratecfg_getrate(struct tc_ratespec *res, 793 const struct psched_ratecfg *r) 794 { 795 memset(res, 0, sizeof(*res)); 796 797 /* legacy struct tc_ratespec has a 32bit @rate field 798 * Qdisc using 64bit rate should add new attributes 799 * in order to maintain compatibility. 800 */ 801 res->rate = min_t(u64, r->rate_bytes_ps, ~0U); 802 803 res->overhead = r->overhead; 804 res->linklayer = (r->linklayer & TC_LINKLAYER_MASK); 805 } 806 807 #endif 808