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 __QDISC_STATE_THROTTLED, 30 }; 31 32 /* 33 * following bits are only changed while qdisc lock is held 34 */ 35 enum qdisc___state_t { 36 __QDISC___STATE_RUNNING = 1, 37 }; 38 39 struct qdisc_size_table { 40 struct rcu_head rcu; 41 struct list_head list; 42 struct tc_sizespec szopts; 43 int refcnt; 44 u16 data[]; 45 }; 46 47 struct Qdisc { 48 int (*enqueue)(struct sk_buff *skb, struct Qdisc *dev); 49 struct sk_buff * (*dequeue)(struct Qdisc *dev); 50 unsigned int flags; 51 #define TCQ_F_BUILTIN 1 52 #define TCQ_F_INGRESS 2 53 #define TCQ_F_CAN_BYPASS 4 54 #define TCQ_F_MQROOT 8 55 #define TCQ_F_ONETXQUEUE 0x10 /* dequeue_skb() can assume all skbs are for 56 * q->dev_queue : It can test 57 * netif_xmit_frozen_or_stopped() before 58 * dequeueing next packet. 59 * Its true for MQ/MQPRIO slaves, or non 60 * multiqueue device. 61 */ 62 #define TCQ_F_WARN_NONWC (1 << 16) 63 #define TCQ_F_CPUSTATS 0x20 /* run using percpu statistics */ 64 #define TCQ_F_NOPARENT 0x40 /* root of its hierarchy : 65 * qdisc_tree_decrease_qlen() should stop. 66 */ 67 u32 limit; 68 const struct Qdisc_ops *ops; 69 struct qdisc_size_table __rcu *stab; 70 struct list_head list; 71 u32 handle; 72 u32 parent; 73 int (*reshape_fail)(struct sk_buff *skb, 74 struct Qdisc *q); 75 76 void *u32_node; 77 78 /* This field is deprecated, but it is still used by CBQ 79 * and it will live until better solution will be invented. 80 */ 81 struct Qdisc *__parent; 82 struct netdev_queue *dev_queue; 83 84 struct gnet_stats_rate_est64 rate_est; 85 struct gnet_stats_basic_cpu __percpu *cpu_bstats; 86 struct gnet_stats_queue __percpu *cpu_qstats; 87 88 struct Qdisc *next_sched; 89 struct sk_buff *gso_skb; 90 /* 91 * For performance sake on SMP, we put highly modified fields at the end 92 */ 93 unsigned long state; 94 struct sk_buff_head q; 95 struct gnet_stats_basic_packed bstats; 96 unsigned int __state; 97 struct gnet_stats_queue qstats; 98 struct rcu_head rcu_head; 99 int padded; 100 atomic_t refcnt; 101 102 spinlock_t busylock ____cacheline_aligned_in_smp; 103 }; 104 105 static inline bool qdisc_is_running(const struct Qdisc *qdisc) 106 { 107 return (qdisc->__state & __QDISC___STATE_RUNNING) ? true : false; 108 } 109 110 static inline bool qdisc_run_begin(struct Qdisc *qdisc) 111 { 112 if (qdisc_is_running(qdisc)) 113 return false; 114 qdisc->__state |= __QDISC___STATE_RUNNING; 115 return true; 116 } 117 118 static inline void qdisc_run_end(struct Qdisc *qdisc) 119 { 120 qdisc->__state &= ~__QDISC___STATE_RUNNING; 121 } 122 123 static inline bool qdisc_may_bulk(const struct Qdisc *qdisc) 124 { 125 return qdisc->flags & TCQ_F_ONETXQUEUE; 126 } 127 128 static inline int qdisc_avail_bulklimit(const struct netdev_queue *txq) 129 { 130 #ifdef CONFIG_BQL 131 /* Non-BQL migrated drivers will return 0, too. */ 132 return dql_avail(&txq->dql); 133 #else 134 return 0; 135 #endif 136 } 137 138 static inline bool qdisc_is_throttled(const struct Qdisc *qdisc) 139 { 140 return test_bit(__QDISC_STATE_THROTTLED, &qdisc->state) ? true : false; 141 } 142 143 static inline void qdisc_throttled(struct Qdisc *qdisc) 144 { 145 set_bit(__QDISC_STATE_THROTTLED, &qdisc->state); 146 } 147 148 static inline void qdisc_unthrottled(struct Qdisc *qdisc) 149 { 150 clear_bit(__QDISC_STATE_THROTTLED, &qdisc->state); 151 } 152 153 struct Qdisc_class_ops { 154 /* Child qdisc manipulation */ 155 struct netdev_queue * (*select_queue)(struct Qdisc *, struct tcmsg *); 156 int (*graft)(struct Qdisc *, unsigned long cl, 157 struct Qdisc *, struct Qdisc **); 158 struct Qdisc * (*leaf)(struct Qdisc *, unsigned long cl); 159 void (*qlen_notify)(struct Qdisc *, unsigned long); 160 161 /* Class manipulation routines */ 162 unsigned long (*get)(struct Qdisc *, u32 classid); 163 void (*put)(struct Qdisc *, unsigned long); 164 int (*change)(struct Qdisc *, u32, u32, 165 struct nlattr **, unsigned long *); 166 int (*delete)(struct Qdisc *, unsigned long); 167 void (*walk)(struct Qdisc *, struct qdisc_walker * arg); 168 169 /* Filter manipulation */ 170 struct tcf_proto __rcu ** (*tcf_chain)(struct Qdisc *, unsigned long); 171 bool (*tcf_cl_offload)(u32 classid); 172 unsigned long (*bind_tcf)(struct Qdisc *, unsigned long, 173 u32 classid); 174 void (*unbind_tcf)(struct Qdisc *, unsigned long); 175 176 /* rtnetlink specific */ 177 int (*dump)(struct Qdisc *, unsigned long, 178 struct sk_buff *skb, struct tcmsg*); 179 int (*dump_stats)(struct Qdisc *, unsigned long, 180 struct gnet_dump *); 181 }; 182 183 struct Qdisc_ops { 184 struct Qdisc_ops *next; 185 const struct Qdisc_class_ops *cl_ops; 186 char id[IFNAMSIZ]; 187 int priv_size; 188 189 int (*enqueue)(struct sk_buff *, struct Qdisc *); 190 struct sk_buff * (*dequeue)(struct Qdisc *); 191 struct sk_buff * (*peek)(struct Qdisc *); 192 unsigned int (*drop)(struct Qdisc *); 193 194 int (*init)(struct Qdisc *, struct nlattr *arg); 195 void (*reset)(struct Qdisc *); 196 void (*destroy)(struct Qdisc *); 197 int (*change)(struct Qdisc *, struct nlattr *arg); 198 void (*attach)(struct Qdisc *); 199 200 int (*dump)(struct Qdisc *, struct sk_buff *); 201 int (*dump_stats)(struct Qdisc *, struct gnet_dump *); 202 203 struct module *owner; 204 }; 205 206 207 struct tcf_result { 208 unsigned long class; 209 u32 classid; 210 }; 211 212 struct tcf_proto_ops { 213 struct list_head head; 214 char kind[IFNAMSIZ]; 215 216 int (*classify)(struct sk_buff *, 217 const struct tcf_proto *, 218 struct tcf_result *); 219 int (*init)(struct tcf_proto*); 220 bool (*destroy)(struct tcf_proto*, bool); 221 222 unsigned long (*get)(struct tcf_proto*, u32 handle); 223 int (*change)(struct net *net, struct sk_buff *, 224 struct tcf_proto*, unsigned long, 225 u32 handle, struct nlattr **, 226 unsigned long *, bool); 227 int (*delete)(struct tcf_proto*, unsigned long); 228 void (*walk)(struct tcf_proto*, struct tcf_walker *arg); 229 230 /* rtnetlink specific */ 231 int (*dump)(struct net*, struct tcf_proto*, unsigned long, 232 struct sk_buff *skb, struct tcmsg*); 233 234 struct module *owner; 235 }; 236 237 struct tcf_proto { 238 /* Fast access part */ 239 struct tcf_proto __rcu *next; 240 void __rcu *root; 241 int (*classify)(struct sk_buff *, 242 const struct tcf_proto *, 243 struct tcf_result *); 244 __be16 protocol; 245 246 /* All the rest */ 247 u32 prio; 248 u32 classid; 249 struct Qdisc *q; 250 void *data; 251 const struct tcf_proto_ops *ops; 252 struct rcu_head rcu; 253 }; 254 255 struct qdisc_skb_cb { 256 unsigned int pkt_len; 257 u16 slave_dev_queue_mapping; 258 u16 tc_classid; 259 #define QDISC_CB_PRIV_LEN 20 260 unsigned char data[QDISC_CB_PRIV_LEN]; 261 }; 262 263 static inline void qdisc_cb_private_validate(const struct sk_buff *skb, int sz) 264 { 265 struct qdisc_skb_cb *qcb; 266 267 BUILD_BUG_ON(sizeof(skb->cb) < offsetof(struct qdisc_skb_cb, data) + sz); 268 BUILD_BUG_ON(sizeof(qcb->data) < sz); 269 } 270 271 static inline int qdisc_qlen(const struct Qdisc *q) 272 { 273 return q->q.qlen; 274 } 275 276 static inline struct qdisc_skb_cb *qdisc_skb_cb(const struct sk_buff *skb) 277 { 278 return (struct qdisc_skb_cb *)skb->cb; 279 } 280 281 static inline spinlock_t *qdisc_lock(struct Qdisc *qdisc) 282 { 283 return &qdisc->q.lock; 284 } 285 286 static inline struct Qdisc *qdisc_root(const struct Qdisc *qdisc) 287 { 288 struct Qdisc *q = rcu_dereference_rtnl(qdisc->dev_queue->qdisc); 289 290 return q; 291 } 292 293 static inline struct Qdisc *qdisc_root_sleeping(const struct Qdisc *qdisc) 294 { 295 return qdisc->dev_queue->qdisc_sleeping; 296 } 297 298 /* The qdisc root lock is a mechanism by which to top level 299 * of a qdisc tree can be locked from any qdisc node in the 300 * forest. This allows changing the configuration of some 301 * aspect of the qdisc tree while blocking out asynchronous 302 * qdisc access in the packet processing paths. 303 * 304 * It is only legal to do this when the root will not change 305 * on us. Otherwise we'll potentially lock the wrong qdisc 306 * root. This is enforced by holding the RTNL semaphore, which 307 * all users of this lock accessor must do. 308 */ 309 static inline spinlock_t *qdisc_root_lock(const struct Qdisc *qdisc) 310 { 311 struct Qdisc *root = qdisc_root(qdisc); 312 313 ASSERT_RTNL(); 314 return qdisc_lock(root); 315 } 316 317 static inline spinlock_t *qdisc_root_sleeping_lock(const struct Qdisc *qdisc) 318 { 319 struct Qdisc *root = qdisc_root_sleeping(qdisc); 320 321 ASSERT_RTNL(); 322 return qdisc_lock(root); 323 } 324 325 static inline struct net_device *qdisc_dev(const struct Qdisc *qdisc) 326 { 327 return qdisc->dev_queue->dev; 328 } 329 330 static inline void sch_tree_lock(const struct Qdisc *q) 331 { 332 spin_lock_bh(qdisc_root_sleeping_lock(q)); 333 } 334 335 static inline void sch_tree_unlock(const struct Qdisc *q) 336 { 337 spin_unlock_bh(qdisc_root_sleeping_lock(q)); 338 } 339 340 #define tcf_tree_lock(tp) sch_tree_lock((tp)->q) 341 #define tcf_tree_unlock(tp) sch_tree_unlock((tp)->q) 342 343 extern struct Qdisc noop_qdisc; 344 extern struct Qdisc_ops noop_qdisc_ops; 345 extern struct Qdisc_ops pfifo_fast_ops; 346 extern struct Qdisc_ops mq_qdisc_ops; 347 extern struct Qdisc_ops noqueue_qdisc_ops; 348 extern const struct Qdisc_ops *default_qdisc_ops; 349 static inline const struct Qdisc_ops * 350 get_default_qdisc_ops(const struct net_device *dev, int ntx) 351 { 352 return ntx < dev->real_num_tx_queues ? 353 default_qdisc_ops : &pfifo_fast_ops; 354 } 355 356 struct Qdisc_class_common { 357 u32 classid; 358 struct hlist_node hnode; 359 }; 360 361 struct Qdisc_class_hash { 362 struct hlist_head *hash; 363 unsigned int hashsize; 364 unsigned int hashmask; 365 unsigned int hashelems; 366 }; 367 368 static inline unsigned int qdisc_class_hash(u32 id, u32 mask) 369 { 370 id ^= id >> 8; 371 id ^= id >> 4; 372 return id & mask; 373 } 374 375 static inline struct Qdisc_class_common * 376 qdisc_class_find(const struct Qdisc_class_hash *hash, u32 id) 377 { 378 struct Qdisc_class_common *cl; 379 unsigned int h; 380 381 h = qdisc_class_hash(id, hash->hashmask); 382 hlist_for_each_entry(cl, &hash->hash[h], hnode) { 383 if (cl->classid == id) 384 return cl; 385 } 386 return NULL; 387 } 388 389 int qdisc_class_hash_init(struct Qdisc_class_hash *); 390 void qdisc_class_hash_insert(struct Qdisc_class_hash *, 391 struct Qdisc_class_common *); 392 void qdisc_class_hash_remove(struct Qdisc_class_hash *, 393 struct Qdisc_class_common *); 394 void qdisc_class_hash_grow(struct Qdisc *, struct Qdisc_class_hash *); 395 void qdisc_class_hash_destroy(struct Qdisc_class_hash *); 396 397 void dev_init_scheduler(struct net_device *dev); 398 void dev_shutdown(struct net_device *dev); 399 void dev_activate(struct net_device *dev); 400 void dev_deactivate(struct net_device *dev); 401 void dev_deactivate_many(struct list_head *head); 402 struct Qdisc *dev_graft_qdisc(struct netdev_queue *dev_queue, 403 struct Qdisc *qdisc); 404 void qdisc_reset(struct Qdisc *qdisc); 405 void qdisc_destroy(struct Qdisc *qdisc); 406 void qdisc_tree_reduce_backlog(struct Qdisc *qdisc, unsigned int n, 407 unsigned int len); 408 struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue, 409 const struct Qdisc_ops *ops); 410 struct Qdisc *qdisc_create_dflt(struct netdev_queue *dev_queue, 411 const struct Qdisc_ops *ops, u32 parentid); 412 void __qdisc_calculate_pkt_len(struct sk_buff *skb, 413 const struct qdisc_size_table *stab); 414 bool tcf_destroy(struct tcf_proto *tp, bool force); 415 void tcf_destroy_chain(struct tcf_proto __rcu **fl); 416 int skb_do_redirect(struct sk_buff *); 417 418 static inline bool skb_at_tc_ingress(const struct sk_buff *skb) 419 { 420 #ifdef CONFIG_NET_CLS_ACT 421 return G_TC_AT(skb->tc_verd) & AT_INGRESS; 422 #else 423 return false; 424 #endif 425 } 426 427 /* Reset all TX qdiscs greater then index of a device. */ 428 static inline void qdisc_reset_all_tx_gt(struct net_device *dev, unsigned int i) 429 { 430 struct Qdisc *qdisc; 431 432 for (; i < dev->num_tx_queues; i++) { 433 qdisc = rtnl_dereference(netdev_get_tx_queue(dev, i)->qdisc); 434 if (qdisc) { 435 spin_lock_bh(qdisc_lock(qdisc)); 436 qdisc_reset(qdisc); 437 spin_unlock_bh(qdisc_lock(qdisc)); 438 } 439 } 440 } 441 442 static inline void qdisc_reset_all_tx(struct net_device *dev) 443 { 444 qdisc_reset_all_tx_gt(dev, 0); 445 } 446 447 /* Are all TX queues of the device empty? */ 448 static inline bool qdisc_all_tx_empty(const struct net_device *dev) 449 { 450 unsigned int i; 451 452 rcu_read_lock(); 453 for (i = 0; i < dev->num_tx_queues; i++) { 454 struct netdev_queue *txq = netdev_get_tx_queue(dev, i); 455 const struct Qdisc *q = rcu_dereference(txq->qdisc); 456 457 if (q->q.qlen) { 458 rcu_read_unlock(); 459 return false; 460 } 461 } 462 rcu_read_unlock(); 463 return true; 464 } 465 466 /* Are any of the TX qdiscs changing? */ 467 static inline bool qdisc_tx_changing(const struct net_device *dev) 468 { 469 unsigned int i; 470 471 for (i = 0; i < dev->num_tx_queues; i++) { 472 struct netdev_queue *txq = netdev_get_tx_queue(dev, i); 473 if (rcu_access_pointer(txq->qdisc) != txq->qdisc_sleeping) 474 return true; 475 } 476 return false; 477 } 478 479 /* Is the device using the noop qdisc on all queues? */ 480 static inline bool qdisc_tx_is_noop(const struct net_device *dev) 481 { 482 unsigned int i; 483 484 for (i = 0; i < dev->num_tx_queues; i++) { 485 struct netdev_queue *txq = netdev_get_tx_queue(dev, i); 486 if (rcu_access_pointer(txq->qdisc) != &noop_qdisc) 487 return false; 488 } 489 return true; 490 } 491 492 static inline unsigned int qdisc_pkt_len(const struct sk_buff *skb) 493 { 494 return qdisc_skb_cb(skb)->pkt_len; 495 } 496 497 /* additional qdisc xmit flags (NET_XMIT_MASK in linux/netdevice.h) */ 498 enum net_xmit_qdisc_t { 499 __NET_XMIT_STOLEN = 0x00010000, 500 __NET_XMIT_BYPASS = 0x00020000, 501 }; 502 503 #ifdef CONFIG_NET_CLS_ACT 504 #define net_xmit_drop_count(e) ((e) & __NET_XMIT_STOLEN ? 0 : 1) 505 #else 506 #define net_xmit_drop_count(e) (1) 507 #endif 508 509 static inline void qdisc_calculate_pkt_len(struct sk_buff *skb, 510 const struct Qdisc *sch) 511 { 512 #ifdef CONFIG_NET_SCHED 513 struct qdisc_size_table *stab = rcu_dereference_bh(sch->stab); 514 515 if (stab) 516 __qdisc_calculate_pkt_len(skb, stab); 517 #endif 518 } 519 520 static inline int qdisc_enqueue(struct sk_buff *skb, struct Qdisc *sch) 521 { 522 qdisc_calculate_pkt_len(skb, sch); 523 return sch->enqueue(skb, sch); 524 } 525 526 static inline bool qdisc_is_percpu_stats(const struct Qdisc *q) 527 { 528 return q->flags & TCQ_F_CPUSTATS; 529 } 530 531 static inline void _bstats_update(struct gnet_stats_basic_packed *bstats, 532 __u64 bytes, __u32 packets) 533 { 534 bstats->bytes += bytes; 535 bstats->packets += packets; 536 } 537 538 static inline void bstats_update(struct gnet_stats_basic_packed *bstats, 539 const struct sk_buff *skb) 540 { 541 _bstats_update(bstats, 542 qdisc_pkt_len(skb), 543 skb_is_gso(skb) ? skb_shinfo(skb)->gso_segs : 1); 544 } 545 546 static inline void _bstats_cpu_update(struct gnet_stats_basic_cpu *bstats, 547 __u64 bytes, __u32 packets) 548 { 549 u64_stats_update_begin(&bstats->syncp); 550 _bstats_update(&bstats->bstats, bytes, packets); 551 u64_stats_update_end(&bstats->syncp); 552 } 553 554 static inline void bstats_cpu_update(struct gnet_stats_basic_cpu *bstats, 555 const struct sk_buff *skb) 556 { 557 u64_stats_update_begin(&bstats->syncp); 558 bstats_update(&bstats->bstats, skb); 559 u64_stats_update_end(&bstats->syncp); 560 } 561 562 static inline void qdisc_bstats_cpu_update(struct Qdisc *sch, 563 const struct sk_buff *skb) 564 { 565 bstats_cpu_update(this_cpu_ptr(sch->cpu_bstats), skb); 566 } 567 568 static inline void qdisc_bstats_update(struct Qdisc *sch, 569 const struct sk_buff *skb) 570 { 571 bstats_update(&sch->bstats, skb); 572 } 573 574 static inline void qdisc_qstats_backlog_dec(struct Qdisc *sch, 575 const struct sk_buff *skb) 576 { 577 sch->qstats.backlog -= qdisc_pkt_len(skb); 578 } 579 580 static inline void qdisc_qstats_backlog_inc(struct Qdisc *sch, 581 const struct sk_buff *skb) 582 { 583 sch->qstats.backlog += qdisc_pkt_len(skb); 584 } 585 586 static inline void __qdisc_qstats_drop(struct Qdisc *sch, int count) 587 { 588 sch->qstats.drops += count; 589 } 590 591 static inline void qstats_drop_inc(struct gnet_stats_queue *qstats) 592 { 593 qstats->drops++; 594 } 595 596 static inline void qstats_overlimit_inc(struct gnet_stats_queue *qstats) 597 { 598 qstats->overlimits++; 599 } 600 601 static inline void qdisc_qstats_drop(struct Qdisc *sch) 602 { 603 qstats_drop_inc(&sch->qstats); 604 } 605 606 static inline void qdisc_qstats_cpu_drop(struct Qdisc *sch) 607 { 608 qstats_drop_inc(this_cpu_ptr(sch->cpu_qstats)); 609 } 610 611 static inline void qdisc_qstats_overlimit(struct Qdisc *sch) 612 { 613 sch->qstats.overlimits++; 614 } 615 616 static inline int __qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch, 617 struct sk_buff_head *list) 618 { 619 __skb_queue_tail(list, skb); 620 qdisc_qstats_backlog_inc(sch, skb); 621 622 return NET_XMIT_SUCCESS; 623 } 624 625 static inline int qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch) 626 { 627 return __qdisc_enqueue_tail(skb, sch, &sch->q); 628 } 629 630 static inline struct sk_buff *__qdisc_dequeue_head(struct Qdisc *sch, 631 struct sk_buff_head *list) 632 { 633 struct sk_buff *skb = __skb_dequeue(list); 634 635 if (likely(skb != NULL)) { 636 qdisc_qstats_backlog_dec(sch, skb); 637 qdisc_bstats_update(sch, skb); 638 } 639 640 return skb; 641 } 642 643 static inline struct sk_buff *qdisc_dequeue_head(struct Qdisc *sch) 644 { 645 return __qdisc_dequeue_head(sch, &sch->q); 646 } 647 648 static inline unsigned int __qdisc_queue_drop_head(struct Qdisc *sch, 649 struct sk_buff_head *list) 650 { 651 struct sk_buff *skb = __skb_dequeue(list); 652 653 if (likely(skb != NULL)) { 654 unsigned int len = qdisc_pkt_len(skb); 655 qdisc_qstats_backlog_dec(sch, skb); 656 kfree_skb(skb); 657 return len; 658 } 659 660 return 0; 661 } 662 663 static inline unsigned int qdisc_queue_drop_head(struct Qdisc *sch) 664 { 665 return __qdisc_queue_drop_head(sch, &sch->q); 666 } 667 668 static inline struct sk_buff *__qdisc_dequeue_tail(struct Qdisc *sch, 669 struct sk_buff_head *list) 670 { 671 struct sk_buff *skb = __skb_dequeue_tail(list); 672 673 if (likely(skb != NULL)) 674 qdisc_qstats_backlog_dec(sch, skb); 675 676 return skb; 677 } 678 679 static inline struct sk_buff *qdisc_dequeue_tail(struct Qdisc *sch) 680 { 681 return __qdisc_dequeue_tail(sch, &sch->q); 682 } 683 684 static inline struct sk_buff *qdisc_peek_head(struct Qdisc *sch) 685 { 686 return skb_peek(&sch->q); 687 } 688 689 /* generic pseudo peek method for non-work-conserving qdisc */ 690 static inline struct sk_buff *qdisc_peek_dequeued(struct Qdisc *sch) 691 { 692 /* we can reuse ->gso_skb because peek isn't called for root qdiscs */ 693 if (!sch->gso_skb) { 694 sch->gso_skb = sch->dequeue(sch); 695 if (sch->gso_skb) { 696 /* it's still part of the queue */ 697 qdisc_qstats_backlog_inc(sch, sch->gso_skb); 698 sch->q.qlen++; 699 } 700 } 701 702 return sch->gso_skb; 703 } 704 705 /* use instead of qdisc->dequeue() for all qdiscs queried with ->peek() */ 706 static inline struct sk_buff *qdisc_dequeue_peeked(struct Qdisc *sch) 707 { 708 struct sk_buff *skb = sch->gso_skb; 709 710 if (skb) { 711 sch->gso_skb = NULL; 712 qdisc_qstats_backlog_dec(sch, skb); 713 sch->q.qlen--; 714 } else { 715 skb = sch->dequeue(sch); 716 } 717 718 return skb; 719 } 720 721 static inline void __qdisc_reset_queue(struct Qdisc *sch, 722 struct sk_buff_head *list) 723 { 724 /* 725 * We do not know the backlog in bytes of this list, it 726 * is up to the caller to correct it 727 */ 728 __skb_queue_purge(list); 729 } 730 731 static inline void qdisc_reset_queue(struct Qdisc *sch) 732 { 733 __qdisc_reset_queue(sch, &sch->q); 734 sch->qstats.backlog = 0; 735 } 736 737 static inline struct Qdisc *qdisc_replace(struct Qdisc *sch, struct Qdisc *new, 738 struct Qdisc **pold) 739 { 740 struct Qdisc *old; 741 742 sch_tree_lock(sch); 743 old = *pold; 744 *pold = new; 745 if (old != NULL) { 746 qdisc_tree_reduce_backlog(old, old->q.qlen, old->qstats.backlog); 747 qdisc_reset(old); 748 } 749 sch_tree_unlock(sch); 750 751 return old; 752 } 753 754 static inline unsigned int __qdisc_queue_drop(struct Qdisc *sch, 755 struct sk_buff_head *list) 756 { 757 struct sk_buff *skb = __qdisc_dequeue_tail(sch, list); 758 759 if (likely(skb != NULL)) { 760 unsigned int len = qdisc_pkt_len(skb); 761 kfree_skb(skb); 762 return len; 763 } 764 765 return 0; 766 } 767 768 static inline unsigned int qdisc_queue_drop(struct Qdisc *sch) 769 { 770 return __qdisc_queue_drop(sch, &sch->q); 771 } 772 773 static inline int qdisc_drop(struct sk_buff *skb, struct Qdisc *sch) 774 { 775 kfree_skb(skb); 776 qdisc_qstats_drop(sch); 777 778 return NET_XMIT_DROP; 779 } 780 781 static inline int qdisc_reshape_fail(struct sk_buff *skb, struct Qdisc *sch) 782 { 783 qdisc_qstats_drop(sch); 784 785 #ifdef CONFIG_NET_CLS_ACT 786 if (sch->reshape_fail == NULL || sch->reshape_fail(skb, sch)) 787 goto drop; 788 789 return NET_XMIT_SUCCESS; 790 791 drop: 792 #endif 793 kfree_skb(skb); 794 return NET_XMIT_DROP; 795 } 796 797 /* Length to Time (L2T) lookup in a qdisc_rate_table, to determine how 798 long it will take to send a packet given its size. 799 */ 800 static inline u32 qdisc_l2t(struct qdisc_rate_table* rtab, unsigned int pktlen) 801 { 802 int slot = pktlen + rtab->rate.cell_align + rtab->rate.overhead; 803 if (slot < 0) 804 slot = 0; 805 slot >>= rtab->rate.cell_log; 806 if (slot > 255) 807 return rtab->data[255]*(slot >> 8) + rtab->data[slot & 0xFF]; 808 return rtab->data[slot]; 809 } 810 811 struct psched_ratecfg { 812 u64 rate_bytes_ps; /* bytes per second */ 813 u32 mult; 814 u16 overhead; 815 u8 linklayer; 816 u8 shift; 817 }; 818 819 static inline u64 psched_l2t_ns(const struct psched_ratecfg *r, 820 unsigned int len) 821 { 822 len += r->overhead; 823 824 if (unlikely(r->linklayer == TC_LINKLAYER_ATM)) 825 return ((u64)(DIV_ROUND_UP(len,48)*53) * r->mult) >> r->shift; 826 827 return ((u64)len * r->mult) >> r->shift; 828 } 829 830 void psched_ratecfg_precompute(struct psched_ratecfg *r, 831 const struct tc_ratespec *conf, 832 u64 rate64); 833 834 static inline void psched_ratecfg_getrate(struct tc_ratespec *res, 835 const struct psched_ratecfg *r) 836 { 837 memset(res, 0, sizeof(*res)); 838 839 /* legacy struct tc_ratespec has a 32bit @rate field 840 * Qdisc using 64bit rate should add new attributes 841 * in order to maintain compatibility. 842 */ 843 res->rate = min_t(u64, r->rate_bytes_ps, ~0U); 844 845 res->overhead = r->overhead; 846 res->linklayer = (r->linklayer & TC_LINKLAYER_MASK); 847 } 848 849 #endif 850