sch_generic.h 19 KB

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