]> git.proxmox.com Git - mirror_ubuntu-bionic-kernel.git/blob - include/net/sch_generic.h
projects / mirror_ubuntu-bionic-kernel.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
net_sched: remove tc class reference counting
[mirror_ubuntu-bionic-kernel.git] / include / net / sch_generic.h
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 <linux/list.h>
12 #include <linux/refcount.h>
13 #include <net/gen_stats.h>
14 #include <net/rtnetlink.h>
15
16 struct Qdisc_ops;
17 struct qdisc_walker;
18 struct tcf_walker;
19 struct module;
20
21 struct qdisc_rate_table {
22 struct tc_ratespec rate;
23 u32 data[256];
24 struct qdisc_rate_table *next;
25 int refcnt;
26 };
27
28 enum qdisc_state_t {
29 __QDISC_STATE_SCHED,
30 __QDISC_STATE_DEACTIVATED,
31 };
32
33 struct qdisc_size_table {
34 struct rcu_head rcu;
35 struct list_head list;
36 struct tc_sizespec szopts;
37 int refcnt;
38 u16 data[];
39 };
40
41 /* similar to sk_buff_head, but skb->prev pointer is undefined. */
42 struct qdisc_skb_head {
43 struct sk_buff *head;
44 struct sk_buff *tail;
45 __u32 qlen;
46 spinlock_t lock;
47 };
48
49 struct Qdisc {
50 int (*enqueue)(struct sk_buff *skb,
51 struct Qdisc *sch,
52 struct sk_buff **to_free);
53 struct sk_buff * (*dequeue)(struct Qdisc *sch);
54 unsigned int flags;
55 #define TCQ_F_BUILTIN 1
56 #define TCQ_F_INGRESS 2
57 #define TCQ_F_CAN_BYPASS 4
58 #define TCQ_F_MQROOT 8
59 #define TCQ_F_ONETXQUEUE 0x10 /* dequeue_skb() can assume all skbs are for
60 * q->dev_queue : It can test
61 * netif_xmit_frozen_or_stopped() before
62 * dequeueing next packet.
63 * Its true for MQ/MQPRIO slaves, or non
64 * multiqueue device.
65 */
66 #define TCQ_F_WARN_NONWC (1 << 16)
67 #define TCQ_F_CPUSTATS 0x20 /* run using percpu statistics */
68 #define TCQ_F_NOPARENT 0x40 /* root of its hierarchy :
69 * qdisc_tree_decrease_qlen() should stop.
70 */
71 #define TCQ_F_INVISIBLE 0x80 /* invisible by default in dump */
72 u32 limit;
73 const struct Qdisc_ops *ops;
74 struct qdisc_size_table __rcu *stab;
75 struct hlist_node hash;
76 u32 handle;
77 u32 parent;
78 void *u32_node;
79
80 struct netdev_queue *dev_queue;
81
82 struct net_rate_estimator __rcu *rate_est;
83 struct gnet_stats_basic_cpu __percpu *cpu_bstats;
84 struct gnet_stats_queue __percpu *cpu_qstats;
85
86 /*
87 * For performance sake on SMP, we put highly modified fields at the end
88 */
89 struct sk_buff *gso_skb ____cacheline_aligned_in_smp;
90 struct qdisc_skb_head q;
91 struct gnet_stats_basic_packed bstats;
92 seqcount_t running;
93 struct gnet_stats_queue qstats;
94 unsigned long state;
95 struct Qdisc *next_sched;
96 struct sk_buff *skb_bad_txq;
97 struct rcu_head rcu_head;
98 int padded;
99 refcount_t refcnt;
100
101 spinlock_t busylock ____cacheline_aligned_in_smp;
102 };
103
104 static inline bool qdisc_is_running(const struct Qdisc *qdisc)
105 {
106 return (raw_read_seqcount(&qdisc->running) & 1) ? true : false;
107 }
108
109 static inline bool qdisc_run_begin(struct Qdisc *qdisc)
110 {
111 if (qdisc_is_running(qdisc))
112 return false;
113 /* Variant of write_seqcount_begin() telling lockdep a trylock
114 * was attempted.
115 */
116 raw_write_seqcount_begin(&qdisc->running);
117 seqcount_acquire(&qdisc->running.dep_map, 0, 1, _RET_IP_);
118 return true;
119 }
120
121 static inline void qdisc_run_end(struct Qdisc *qdisc)
122 {
123 write_seqcount_end(&qdisc->running);
124 }
125
126 static inline bool qdisc_may_bulk(const struct Qdisc *qdisc)
127 {
128 return qdisc->flags & TCQ_F_ONETXQUEUE;
129 }
130
131 static inline int qdisc_avail_bulklimit(const struct netdev_queue *txq)
132 {
133 #ifdef CONFIG_BQL
134 /* Non-BQL migrated drivers will return 0, too. */
135 return dql_avail(&txq->dql);
136 #else
137 return 0;
138 #endif
139 }
140
141 struct Qdisc_class_ops {
142 /* Child qdisc manipulation */
143 struct netdev_queue * (*select_queue)(struct Qdisc *, struct tcmsg *);
144 int (*graft)(struct Qdisc *, unsigned long cl,
145 struct Qdisc *, struct Qdisc **);
146 struct Qdisc * (*leaf)(struct Qdisc *, unsigned long cl);
147 void (*qlen_notify)(struct Qdisc *, unsigned long);
148
149 /* Class manipulation routines */
150 unsigned long (*find)(struct Qdisc *, u32 classid);
151 int (*change)(struct Qdisc *, u32, u32,
152 struct nlattr **, unsigned long *);
153 int (*delete)(struct Qdisc *, unsigned long);
154 void (*walk)(struct Qdisc *, struct qdisc_walker * arg);
155
156 /* Filter manipulation */
157 struct tcf_block * (*tcf_block)(struct Qdisc *, unsigned long);
158 unsigned long (*bind_tcf)(struct Qdisc *, unsigned long,
159 u32 classid);
160 void (*unbind_tcf)(struct Qdisc *, unsigned long);
161
162 /* rtnetlink specific */
163 int (*dump)(struct Qdisc *, unsigned long,
164 struct sk_buff *skb, struct tcmsg*);
165 int (*dump_stats)(struct Qdisc *, unsigned long,
166 struct gnet_dump *);
167 };
168
169 struct Qdisc_ops {
170 struct Qdisc_ops *next;
171 const struct Qdisc_class_ops *cl_ops;
172 char id[IFNAMSIZ];
173 int priv_size;
174
175 int (*enqueue)(struct sk_buff *skb,
176 struct Qdisc *sch,
177 struct sk_buff **to_free);
178 struct sk_buff * (*dequeue)(struct Qdisc *);
179 struct sk_buff * (*peek)(struct Qdisc *);
180
181 int (*init)(struct Qdisc *, struct nlattr *arg);
182 void (*reset)(struct Qdisc *);
183 void (*destroy)(struct Qdisc *);
184 int (*change)(struct Qdisc *, struct nlattr *arg);
185 void (*attach)(struct Qdisc *);
186
187 int (*dump)(struct Qdisc *, struct sk_buff *);
188 int (*dump_stats)(struct Qdisc *, struct gnet_dump *);
189
190 struct module *owner;
191 };
192
193
194 struct tcf_result {
195 union {
196 struct {
197 unsigned long class;
198 u32 classid;
199 };
200 const struct tcf_proto *goto_tp;
201 };
202 };
203
204 struct tcf_proto_ops {
205 struct list_head head;
206 char kind[IFNAMSIZ];
207
208 int (*classify)(struct sk_buff *,
209 const struct tcf_proto *,
210 struct tcf_result *);
211 int (*init)(struct tcf_proto*);
212 void (*destroy)(struct tcf_proto*);
213
214 void* (*get)(struct tcf_proto*, u32 handle);
215 int (*change)(struct net *net, struct sk_buff *,
216 struct tcf_proto*, unsigned long,
217 u32 handle, struct nlattr **,
218 void **, bool);
219 int (*delete)(struct tcf_proto*, void *, bool*);
220 void (*walk)(struct tcf_proto*, struct tcf_walker *arg);
221
222 /* rtnetlink specific */
223 int (*dump)(struct net*, struct tcf_proto*, void *,
224 struct sk_buff *skb, struct tcmsg*);
225
226 struct module *owner;
227 };
228
229 struct tcf_proto {
230 /* Fast access part */
231 struct tcf_proto __rcu *next;
232 void __rcu *root;
233 int (*classify)(struct sk_buff *,
234 const struct tcf_proto *,
235 struct tcf_result *);
236 __be16 protocol;
237
238 /* All the rest */
239 u32 prio;
240 u32 classid;
241 struct Qdisc *q;
242 void *data;
243 const struct tcf_proto_ops *ops;
244 struct tcf_chain *chain;
245 struct rcu_head rcu;
246 };
247
248 struct qdisc_skb_cb {
249 unsigned int pkt_len;
250 u16 slave_dev_queue_mapping;
251 u16 tc_classid;
252 #define QDISC_CB_PRIV_LEN 20
253 unsigned char data[QDISC_CB_PRIV_LEN];
254 };
255
256 struct tcf_chain {
257 struct tcf_proto __rcu *filter_chain;
258 struct tcf_proto __rcu **p_filter_chain;
259 struct list_head list;
260 struct tcf_block *block;
261 u32 index; /* chain index */
262 unsigned int refcnt;
263 };
264
265 struct tcf_block {
266 struct list_head chain_list;
267 };
268
269 static inline void qdisc_cb_private_validate(const struct sk_buff *skb, int sz)
270 {
271 struct qdisc_skb_cb *qcb;
272
273 BUILD_BUG_ON(sizeof(skb->cb) < offsetof(struct qdisc_skb_cb, data) + sz);
274 BUILD_BUG_ON(sizeof(qcb->data) < sz);
275 }
276
277 static inline int qdisc_qlen(const struct Qdisc *q)
278 {
279 return q->q.qlen;
280 }
281
282 static inline struct qdisc_skb_cb *qdisc_skb_cb(const struct sk_buff *skb)
283 {
284 return (struct qdisc_skb_cb *)skb->cb;
285 }
286
287 static inline spinlock_t *qdisc_lock(struct Qdisc *qdisc)
288 {
289 return &qdisc->q.lock;
290 }
291
292 static inline struct Qdisc *qdisc_root(const struct Qdisc *qdisc)
293 {
294 struct Qdisc *q = rcu_dereference_rtnl(qdisc->dev_queue->qdisc);
295
296 return q;
297 }
298
299 static inline struct Qdisc *qdisc_root_sleeping(const struct Qdisc *qdisc)
300 {
301 return qdisc->dev_queue->qdisc_sleeping;
302 }
303
304 /* The qdisc root lock is a mechanism by which to top level
305 * of a qdisc tree can be locked from any qdisc node in the
306 * forest. This allows changing the configuration of some
307 * aspect of the qdisc tree while blocking out asynchronous
308 * qdisc access in the packet processing paths.
309 *
310 * It is only legal to do this when the root will not change
311 * on us. Otherwise we'll potentially lock the wrong qdisc
312 * root. This is enforced by holding the RTNL semaphore, which
313 * all users of this lock accessor must do.
314 */
315 static inline spinlock_t *qdisc_root_lock(const struct Qdisc *qdisc)
316 {
317 struct Qdisc *root = qdisc_root(qdisc);
318
319 ASSERT_RTNL();
320 return qdisc_lock(root);
321 }
322
323 static inline spinlock_t *qdisc_root_sleeping_lock(const struct Qdisc *qdisc)
324 {
325 struct Qdisc *root = qdisc_root_sleeping(qdisc);
326
327 ASSERT_RTNL();
328 return qdisc_lock(root);
329 }
330
331 static inline seqcount_t *qdisc_root_sleeping_running(const struct Qdisc *qdisc)
332 {
333 struct Qdisc *root = qdisc_root_sleeping(qdisc);
334
335 ASSERT_RTNL();
336 return &root->running;
337 }
338
339 static inline struct net_device *qdisc_dev(const struct Qdisc *qdisc)
340 {
341 return qdisc->dev_queue->dev;
342 }
343
344 static inline void sch_tree_lock(const struct Qdisc *q)
345 {
346 spin_lock_bh(qdisc_root_sleeping_lock(q));
347 }
348
349 static inline void sch_tree_unlock(const struct Qdisc *q)
350 {
351 spin_unlock_bh(qdisc_root_sleeping_lock(q));
352 }
353
354 #define tcf_tree_lock(tp) sch_tree_lock((tp)->q)
355 #define tcf_tree_unlock(tp) sch_tree_unlock((tp)->q)
356
357 extern struct Qdisc noop_qdisc;
358 extern struct Qdisc_ops noop_qdisc_ops;
359 extern struct Qdisc_ops pfifo_fast_ops;
360 extern struct Qdisc_ops mq_qdisc_ops;
361 extern struct Qdisc_ops noqueue_qdisc_ops;
362 extern const struct Qdisc_ops *default_qdisc_ops;
363 static inline const struct Qdisc_ops *
364 get_default_qdisc_ops(const struct net_device *dev, int ntx)
365 {
366 return ntx < dev->real_num_tx_queues ?
367 default_qdisc_ops : &pfifo_fast_ops;
368 }
369
370 struct Qdisc_class_common {
371 u32 classid;
372 struct hlist_node hnode;
373 };
374
375 struct Qdisc_class_hash {
376 struct hlist_head *hash;
377 unsigned int hashsize;
378 unsigned int hashmask;
379 unsigned int hashelems;
380 };
381
382 static inline unsigned int qdisc_class_hash(u32 id, u32 mask)
383 {
384 id ^= id >> 8;
385 id ^= id >> 4;
386 return id & mask;
387 }
388
389 static inline struct Qdisc_class_common *
390 qdisc_class_find(const struct Qdisc_class_hash *hash, u32 id)
391 {
392 struct Qdisc_class_common *cl;
393 unsigned int h;
394
395 if (!id)
396 return NULL;
397
398 h = qdisc_class_hash(id, hash->hashmask);
399 hlist_for_each_entry(cl, &hash->hash[h], hnode) {
400 if (cl->classid == id)
401 return cl;
402 }
403 return NULL;
404 }
405
406 int qdisc_class_hash_init(struct Qdisc_class_hash *);
407 void qdisc_class_hash_insert(struct Qdisc_class_hash *,
408 struct Qdisc_class_common *);
409 void qdisc_class_hash_remove(struct Qdisc_class_hash *,
410 struct Qdisc_class_common *);
411 void qdisc_class_hash_grow(struct Qdisc *, struct Qdisc_class_hash *);
412 void qdisc_class_hash_destroy(struct Qdisc_class_hash *);
413
414 void dev_init_scheduler(struct net_device *dev);
415 void dev_shutdown(struct net_device *dev);
416 void dev_activate(struct net_device *dev);
417 void dev_deactivate(struct net_device *dev);
418 void dev_deactivate_many(struct list_head *head);
419 struct Qdisc *dev_graft_qdisc(struct netdev_queue *dev_queue,
420 struct Qdisc *qdisc);
421 void qdisc_reset(struct Qdisc *qdisc);
422 void qdisc_destroy(struct Qdisc *qdisc);
423 void qdisc_tree_reduce_backlog(struct Qdisc *qdisc, unsigned int n,
424 unsigned int len);
425 struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue,
426 const struct Qdisc_ops *ops);
427 struct Qdisc *qdisc_create_dflt(struct netdev_queue *dev_queue,
428 const struct Qdisc_ops *ops, u32 parentid);
429 void __qdisc_calculate_pkt_len(struct sk_buff *skb,
430 const struct qdisc_size_table *stab);
431 int skb_do_redirect(struct sk_buff *);
432
433 static inline void skb_reset_tc(struct sk_buff *skb)
434 {
435 #ifdef CONFIG_NET_CLS_ACT
436 skb->tc_redirected = 0;
437 #endif
438 }
439
440 static inline bool skb_at_tc_ingress(const struct sk_buff *skb)
441 {
442 #ifdef CONFIG_NET_CLS_ACT
443 return skb->tc_at_ingress;
444 #else
445 return false;
446 #endif
447 }
448
449 static inline bool skb_skip_tc_classify(struct sk_buff *skb)
450 {
451 #ifdef CONFIG_NET_CLS_ACT
452 if (skb->tc_skip_classify) {
453 skb->tc_skip_classify = 0;
454 return true;
455 }
456 #endif
457 return false;
458 }
459
460 /* Reset all TX qdiscs greater then index of a device. */
461 static inline void qdisc_reset_all_tx_gt(struct net_device *dev, unsigned int i)
462 {
463 struct Qdisc *qdisc;
464
465 for (; i < dev->num_tx_queues; i++) {
466 qdisc = rtnl_dereference(netdev_get_tx_queue(dev, i)->qdisc);
467 if (qdisc) {
468 spin_lock_bh(qdisc_lock(qdisc));
469 qdisc_reset(qdisc);
470 spin_unlock_bh(qdisc_lock(qdisc));
471 }
472 }
473 }
474
475 static inline void qdisc_reset_all_tx(struct net_device *dev)
476 {
477 qdisc_reset_all_tx_gt(dev, 0);
478 }
479
480 /* Are all TX queues of the device empty? */
481 static inline bool qdisc_all_tx_empty(const struct net_device *dev)
482 {
483 unsigned int i;
484
485 rcu_read_lock();
486 for (i = 0; i < dev->num_tx_queues; i++) {
487 struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
488 const struct Qdisc *q = rcu_dereference(txq->qdisc);
489
490 if (q->q.qlen) {
491 rcu_read_unlock();
492 return false;
493 }
494 }
495 rcu_read_unlock();
496 return true;
497 }
498
499 /* Are any of the TX qdiscs changing? */
500 static inline bool qdisc_tx_changing(const struct net_device *dev)
501 {
502 unsigned int i;
503
504 for (i = 0; i < dev->num_tx_queues; i++) {
505 struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
506 if (rcu_access_pointer(txq->qdisc) != txq->qdisc_sleeping)
507 return true;
508 }
509 return false;
510 }
511
512 /* Is the device using the noop qdisc on all queues? */
513 static inline bool qdisc_tx_is_noop(const struct net_device *dev)
514 {
515 unsigned int i;
516
517 for (i = 0; i < dev->num_tx_queues; i++) {
518 struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
519 if (rcu_access_pointer(txq->qdisc) != &noop_qdisc)
520 return false;
521 }
522 return true;
523 }
524
525 static inline unsigned int qdisc_pkt_len(const struct sk_buff *skb)
526 {
527 return qdisc_skb_cb(skb)->pkt_len;
528 }
529
530 /* additional qdisc xmit flags (NET_XMIT_MASK in linux/netdevice.h) */
531 enum net_xmit_qdisc_t {
532 __NET_XMIT_STOLEN = 0x00010000,
533 __NET_XMIT_BYPASS = 0x00020000,
534 };
535
536 #ifdef CONFIG_NET_CLS_ACT
537 #define net_xmit_drop_count(e) ((e) & __NET_XMIT_STOLEN ? 0 : 1)
538 #else
539 #define net_xmit_drop_count(e) (1)
540 #endif
541
542 static inline void qdisc_calculate_pkt_len(struct sk_buff *skb,
543 const struct Qdisc *sch)
544 {
545 #ifdef CONFIG_NET_SCHED
546 struct qdisc_size_table *stab = rcu_dereference_bh(sch->stab);
547
548 if (stab)
549 __qdisc_calculate_pkt_len(skb, stab);
550 #endif
551 }
552
553 static inline int qdisc_enqueue(struct sk_buff *skb, struct Qdisc *sch,
554 struct sk_buff **to_free)
555 {
556 qdisc_calculate_pkt_len(skb, sch);
557 return sch->enqueue(skb, sch, to_free);
558 }
559
560 static inline bool qdisc_is_percpu_stats(const struct Qdisc *q)
561 {
562 return q->flags & TCQ_F_CPUSTATS;
563 }
564
565 static inline void _bstats_update(struct gnet_stats_basic_packed *bstats,
566 __u64 bytes, __u32 packets)
567 {
568 bstats->bytes += bytes;
569 bstats->packets += packets;
570 }
571
572 static inline void bstats_update(struct gnet_stats_basic_packed *bstats,
573 const struct sk_buff *skb)
574 {
575 _bstats_update(bstats,
576 qdisc_pkt_len(skb),
577 skb_is_gso(skb) ? skb_shinfo(skb)->gso_segs : 1);
578 }
579
580 static inline void _bstats_cpu_update(struct gnet_stats_basic_cpu *bstats,
581 __u64 bytes, __u32 packets)
582 {
583 u64_stats_update_begin(&bstats->syncp);
584 _bstats_update(&bstats->bstats, bytes, packets);
585 u64_stats_update_end(&bstats->syncp);
586 }
587
588 static inline void bstats_cpu_update(struct gnet_stats_basic_cpu *bstats,
589 const struct sk_buff *skb)
590 {
591 u64_stats_update_begin(&bstats->syncp);
592 bstats_update(&bstats->bstats, skb);
593 u64_stats_update_end(&bstats->syncp);
594 }
595
596 static inline void qdisc_bstats_cpu_update(struct Qdisc *sch,
597 const struct sk_buff *skb)
598 {
599 bstats_cpu_update(this_cpu_ptr(sch->cpu_bstats), skb);
600 }
601
602 static inline void qdisc_bstats_update(struct Qdisc *sch,
603 const struct sk_buff *skb)
604 {
605 bstats_update(&sch->bstats, skb);
606 }
607
608 static inline void qdisc_qstats_backlog_dec(struct Qdisc *sch,
609 const struct sk_buff *skb)
610 {
611 sch->qstats.backlog -= qdisc_pkt_len(skb);
612 }
613
614 static inline void qdisc_qstats_backlog_inc(struct Qdisc *sch,
615 const struct sk_buff *skb)
616 {
617 sch->qstats.backlog += qdisc_pkt_len(skb);
618 }
619
620 static inline void __qdisc_qstats_drop(struct Qdisc *sch, int count)
621 {
622 sch->qstats.drops += count;
623 }
624
625 static inline void qstats_drop_inc(struct gnet_stats_queue *qstats)
626 {
627 qstats->drops++;
628 }
629
630 static inline void qstats_overlimit_inc(struct gnet_stats_queue *qstats)
631 {
632 qstats->overlimits++;
633 }
634
635 static inline void qdisc_qstats_drop(struct Qdisc *sch)
636 {
637 qstats_drop_inc(&sch->qstats);
638 }
639
640 static inline void qdisc_qstats_cpu_drop(struct Qdisc *sch)
641 {
642 this_cpu_inc(sch->cpu_qstats->drops);
643 }
644
645 static inline void qdisc_qstats_overlimit(struct Qdisc *sch)
646 {
647 sch->qstats.overlimits++;
648 }
649
650 static inline void qdisc_skb_head_init(struct qdisc_skb_head *qh)
651 {
652 qh->head = NULL;
653 qh->tail = NULL;
654 qh->qlen = 0;
655 }
656
657 static inline int __qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch,
658 struct qdisc_skb_head *qh)
659 {
660 struct sk_buff *last = qh->tail;
661
662 if (last) {
663 skb->next = NULL;
664 last->next = skb;
665 qh->tail = skb;
666 } else {
667 qh->tail = skb;
668 qh->head = skb;
669 }
670 qh->qlen++;
671 qdisc_qstats_backlog_inc(sch, skb);
672
673 return NET_XMIT_SUCCESS;
674 }
675
676 static inline int qdisc_enqueue_tail(struct sk_buff *skb, struct Qdisc *sch)
677 {
678 return __qdisc_enqueue_tail(skb, sch, &sch->q);
679 }
680
681 static inline struct sk_buff *__qdisc_dequeue_head(struct qdisc_skb_head *qh)
682 {
683 struct sk_buff *skb = qh->head;
684
685 if (likely(skb != NULL)) {
686 qh->head = skb->next;
687 qh->qlen--;
688 if (qh->head == NULL)
689 qh->tail = NULL;
690 skb->next = NULL;
691 }
692
693 return skb;
694 }
695
696 static inline struct sk_buff *qdisc_dequeue_head(struct Qdisc *sch)
697 {
698 struct sk_buff *skb = __qdisc_dequeue_head(&sch->q);
699
700 if (likely(skb != NULL)) {
701 qdisc_qstats_backlog_dec(sch, skb);
702 qdisc_bstats_update(sch, skb);
703 }
704
705 return skb;
706 }
707
708 /* Instead of calling kfree_skb() while root qdisc lock is held,
709 * queue the skb for future freeing at end of __dev_xmit_skb()
710 */
711 static inline void __qdisc_drop(struct sk_buff *skb, struct sk_buff **to_free)
712 {
713 skb->next = *to_free;
714 *to_free = skb;
715 }
716
717 static inline unsigned int __qdisc_queue_drop_head(struct Qdisc *sch,
718 struct qdisc_skb_head *qh,
719 struct sk_buff **to_free)
720 {
721 struct sk_buff *skb = __qdisc_dequeue_head(qh);
722
723 if (likely(skb != NULL)) {
724 unsigned int len = qdisc_pkt_len(skb);
725
726 qdisc_qstats_backlog_dec(sch, skb);
727 __qdisc_drop(skb, to_free);
728 return len;
729 }
730
731 return 0;
732 }
733
734 static inline unsigned int qdisc_queue_drop_head(struct Qdisc *sch,
735 struct sk_buff **to_free)
736 {
737 return __qdisc_queue_drop_head(sch, &sch->q, to_free);
738 }
739
740 static inline struct sk_buff *qdisc_peek_head(struct Qdisc *sch)
741 {
742 const struct qdisc_skb_head *qh = &sch->q;
743
744 return qh->head;
745 }
746
747 /* generic pseudo peek method for non-work-conserving qdisc */
748 static inline struct sk_buff *qdisc_peek_dequeued(struct Qdisc *sch)
749 {
750 /* we can reuse ->gso_skb because peek isn't called for root qdiscs */
751 if (!sch->gso_skb) {
752 sch->gso_skb = sch->dequeue(sch);
753 if (sch->gso_skb) {
754 /* it's still part of the queue */
755 qdisc_qstats_backlog_inc(sch, sch->gso_skb);
756 sch->q.qlen++;
757 }
758 }
759
760 return sch->gso_skb;
761 }
762
763 /* use instead of qdisc->dequeue() for all qdiscs queried with ->peek() */
764 static inline struct sk_buff *qdisc_dequeue_peeked(struct Qdisc *sch)
765 {
766 struct sk_buff *skb = sch->gso_skb;
767
768 if (skb) {
769 sch->gso_skb = NULL;
770 qdisc_qstats_backlog_dec(sch, skb);
771 sch->q.qlen--;
772 } else {
773 skb = sch->dequeue(sch);
774 }
775
776 return skb;
777 }
778
779 static inline void __qdisc_reset_queue(struct qdisc_skb_head *qh)
780 {
781 /*
782 * We do not know the backlog in bytes of this list, it
783 * is up to the caller to correct it
784 */
785 ASSERT_RTNL();
786 if (qh->qlen) {
787 rtnl_kfree_skbs(qh->head, qh->tail);
788
789 qh->head = NULL;
790 qh->tail = NULL;
791 qh->qlen = 0;
792 }
793 }
794
795 static inline void qdisc_reset_queue(struct Qdisc *sch)
796 {
797 __qdisc_reset_queue(&sch->q);
798 sch->qstats.backlog = 0;
799 }
800
801 static inline struct Qdisc *qdisc_replace(struct Qdisc *sch, struct Qdisc *new,
802 struct Qdisc **pold)
803 {
804 struct Qdisc *old;
805
806 sch_tree_lock(sch);
807 old = *pold;
808 *pold = new;
809 if (old != NULL) {
810 unsigned int qlen = old->q.qlen;
811 unsigned int backlog = old->qstats.backlog;
812
813 qdisc_reset(old);
814 qdisc_tree_reduce_backlog(old, qlen, backlog);
815 }
816 sch_tree_unlock(sch);
817
818 return old;
819 }
820
821 static inline void rtnl_qdisc_drop(struct sk_buff *skb, struct Qdisc *sch)
822 {
823 rtnl_kfree_skbs(skb, skb);
824 qdisc_qstats_drop(sch);
825 }
826
827
828 static inline int qdisc_drop(struct sk_buff *skb, struct Qdisc *sch,
829 struct sk_buff **to_free)
830 {
831 __qdisc_drop(skb, to_free);
832 qdisc_qstats_drop(sch);
833
834 return NET_XMIT_DROP;
835 }
836
837 /* Length to Time (L2T) lookup in a qdisc_rate_table, to determine how
838 long it will take to send a packet given its size.
839 */
840 static inline u32 qdisc_l2t(struct qdisc_rate_table* rtab, unsigned int pktlen)
841 {
842 int slot = pktlen + rtab->rate.cell_align + rtab->rate.overhead;
843 if (slot < 0)
844 slot = 0;
845 slot >>= rtab->rate.cell_log;
846 if (slot > 255)
847 return rtab->data[255]*(slot >> 8) + rtab->data[slot & 0xFF];
848 return rtab->data[slot];
849 }
850
851 struct psched_ratecfg {
852 u64 rate_bytes_ps; /* bytes per second */
853 u32 mult;
854 u16 overhead;
855 u8 linklayer;
856 u8 shift;
857 };
858
859 static inline u64 psched_l2t_ns(const struct psched_ratecfg *r,
860 unsigned int len)
861 {
862 len += r->overhead;
863
864 if (unlikely(r->linklayer == TC_LINKLAYER_ATM))
865 return ((u64)(DIV_ROUND_UP(len,48)*53) * r->mult) >> r->shift;
866
867 return ((u64)len * r->mult) >> r->shift;
868 }
869
870 void psched_ratecfg_precompute(struct psched_ratecfg *r,
871 const struct tc_ratespec *conf,
872 u64 rate64);
873
874 static inline void psched_ratecfg_getrate(struct tc_ratespec *res,
875 const struct psched_ratecfg *r)
876 {
877 memset(res, 0, sizeof(*res));
878
879 /* legacy struct tc_ratespec has a 32bit @rate field
880 * Qdisc using 64bit rate should add new attributes
881 * in order to maintain compatibility.
882 */
883 res->rate = min_t(u64, r->rate_bytes_ps, ~0U);
884
885 res->overhead = r->overhead;
886 res->linklayer = (r->linklayer & TC_LINKLAYER_MASK);
887 }
888
889 #endif
ubuntu-bionic-kernel mirror