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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * net/sched/sch_generic.c Generic packet scheduler routines. | |
3 | * | |
4 | * This program is free software; you can redistribute it and/or | |
5 | * modify it under the terms of the GNU General Public License | |
6 | * as published by the Free Software Foundation; either version | |
7 | * 2 of the License, or (at your option) any later version. | |
8 | * | |
9 | * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> | |
10 | * Jamal Hadi Salim, <hadi@cyberus.ca> 990601 | |
11 | * - Ingress support | |
12 | */ | |
13 | ||
14 | #include <asm/uaccess.h> | |
15 | #include <asm/system.h> | |
16 | #include <linux/bitops.h> | |
17 | #include <linux/config.h> | |
18 | #include <linux/module.h> | |
19 | #include <linux/types.h> | |
20 | #include <linux/kernel.h> | |
21 | #include <linux/sched.h> | |
22 | #include <linux/string.h> | |
23 | #include <linux/mm.h> | |
24 | #include <linux/socket.h> | |
25 | #include <linux/sockios.h> | |
26 | #include <linux/in.h> | |
27 | #include <linux/errno.h> | |
28 | #include <linux/interrupt.h> | |
29 | #include <linux/netdevice.h> | |
30 | #include <linux/skbuff.h> | |
31 | #include <linux/rtnetlink.h> | |
32 | #include <linux/init.h> | |
33 | #include <linux/rcupdate.h> | |
34 | #include <linux/list.h> | |
35 | #include <net/sock.h> | |
36 | #include <net/pkt_sched.h> | |
37 | ||
38 | /* Main transmission queue. */ | |
39 | ||
40 | /* Main qdisc structure lock. | |
41 | ||
42 | However, modifications | |
43 | to data, participating in scheduling must be additionally | |
44 | protected with dev->queue_lock spinlock. | |
45 | ||
46 | The idea is the following: | |
47 | - enqueue, dequeue are serialized via top level device | |
48 | spinlock dev->queue_lock. | |
49 | - tree walking is protected by read_lock_bh(qdisc_tree_lock) | |
50 | and this lock is used only in process context. | |
51 | - updates to tree are made under rtnl semaphore or | |
52 | from softirq context (__qdisc_destroy rcu-callback) | |
53 | hence this lock needs local bh disabling. | |
54 | ||
55 | qdisc_tree_lock must be grabbed BEFORE dev->queue_lock! | |
56 | */ | |
57 | DEFINE_RWLOCK(qdisc_tree_lock); | |
58 | ||
59 | void qdisc_lock_tree(struct net_device *dev) | |
60 | { | |
61 | write_lock_bh(&qdisc_tree_lock); | |
62 | spin_lock_bh(&dev->queue_lock); | |
63 | } | |
64 | ||
65 | void qdisc_unlock_tree(struct net_device *dev) | |
66 | { | |
67 | spin_unlock_bh(&dev->queue_lock); | |
68 | write_unlock_bh(&qdisc_tree_lock); | |
69 | } | |
70 | ||
71 | /* | |
72 | dev->queue_lock serializes queue accesses for this device | |
73 | AND dev->qdisc pointer itself. | |
74 | ||
932ff279 | 75 | netif_tx_lock serializes accesses to device driver. |
1da177e4 | 76 | |
932ff279 | 77 | dev->queue_lock and netif_tx_lock are mutually exclusive, |
1da177e4 LT |
78 | if one is grabbed, another must be free. |
79 | */ | |
80 | ||
81 | ||
82 | /* Kick device. | |
83 | Note, that this procedure can be called by a watchdog timer, so that | |
84 | we do not check dev->tbusy flag here. | |
85 | ||
86 | Returns: 0 - queue is empty. | |
87 | >0 - queue is not empty, but throttled. | |
88 | <0 - queue is not empty. Device is throttled, if dev->tbusy != 0. | |
89 | ||
90 | NOTE: Called under dev->queue_lock with locally disabled BH. | |
91 | */ | |
92 | ||
48d83325 | 93 | static inline int qdisc_restart(struct net_device *dev) |
1da177e4 LT |
94 | { |
95 | struct Qdisc *q = dev->qdisc; | |
96 | struct sk_buff *skb; | |
97 | ||
98 | /* Dequeue packet */ | |
99 | if ((skb = q->dequeue(q)) != NULL) { | |
100 | unsigned nolock = (dev->features & NETIF_F_LLTX); | |
101 | /* | |
102 | * When the driver has LLTX set it does its own locking | |
103 | * in start_xmit. No need to add additional overhead by | |
104 | * locking again. These checks are worth it because | |
105 | * even uncongested locks can be quite expensive. | |
106 | * The driver can do trylock like here too, in case | |
107 | * of lock congestion it should return -1 and the packet | |
108 | * will be requeued. | |
109 | */ | |
110 | if (!nolock) { | |
932ff279 | 111 | if (!netif_tx_trylock(dev)) { |
1da177e4 LT |
112 | collision: |
113 | /* So, someone grabbed the driver. */ | |
114 | ||
115 | /* It may be transient configuration error, | |
116 | when hard_start_xmit() recurses. We detect | |
117 | it by checking xmit owner and drop the | |
118 | packet when deadloop is detected. | |
119 | */ | |
120 | if (dev->xmit_lock_owner == smp_processor_id()) { | |
121 | kfree_skb(skb); | |
122 | if (net_ratelimit()) | |
123 | printk(KERN_DEBUG "Dead loop on netdevice %s, fix it urgently!\n", dev->name); | |
124 | return -1; | |
125 | } | |
126 | __get_cpu_var(netdev_rx_stat).cpu_collision++; | |
127 | goto requeue; | |
128 | } | |
1da177e4 LT |
129 | } |
130 | ||
131 | { | |
132 | /* And release queue */ | |
133 | spin_unlock(&dev->queue_lock); | |
134 | ||
135 | if (!netif_queue_stopped(dev)) { | |
136 | int ret; | |
137 | if (netdev_nit) | |
138 | dev_queue_xmit_nit(skb, dev); | |
139 | ||
140 | ret = dev->hard_start_xmit(skb, dev); | |
141 | if (ret == NETDEV_TX_OK) { | |
142 | if (!nolock) { | |
932ff279 | 143 | netif_tx_unlock(dev); |
1da177e4 LT |
144 | } |
145 | spin_lock(&dev->queue_lock); | |
146 | return -1; | |
147 | } | |
148 | if (ret == NETDEV_TX_LOCKED && nolock) { | |
149 | spin_lock(&dev->queue_lock); | |
150 | goto collision; | |
151 | } | |
152 | } | |
153 | ||
154 | /* NETDEV_TX_BUSY - we need to requeue */ | |
155 | /* Release the driver */ | |
156 | if (!nolock) { | |
932ff279 | 157 | netif_tx_unlock(dev); |
1da177e4 LT |
158 | } |
159 | spin_lock(&dev->queue_lock); | |
160 | q = dev->qdisc; | |
161 | } | |
162 | ||
163 | /* Device kicked us out :( | |
164 | This is possible in three cases: | |
165 | ||
166 | 0. driver is locked | |
167 | 1. fastroute is enabled | |
168 | 2. device cannot determine busy state | |
169 | before start of transmission (f.e. dialout) | |
170 | 3. device is buggy (ppp) | |
171 | */ | |
172 | ||
173 | requeue: | |
174 | q->ops->requeue(skb, q); | |
175 | netif_schedule(dev); | |
176 | return 1; | |
177 | } | |
8cbe1d46 | 178 | BUG_ON((int) q->q.qlen < 0); |
1da177e4 LT |
179 | return q->q.qlen; |
180 | } | |
181 | ||
48d83325 HX |
182 | void __qdisc_run(struct net_device *dev) |
183 | { | |
184 | while (qdisc_restart(dev) < 0 && !netif_queue_stopped(dev)) | |
185 | /* NOTHING */; | |
186 | ||
187 | clear_bit(__LINK_STATE_QDISC_RUNNING, &dev->state); | |
188 | } | |
189 | ||
1da177e4 LT |
190 | static void dev_watchdog(unsigned long arg) |
191 | { | |
192 | struct net_device *dev = (struct net_device *)arg; | |
193 | ||
932ff279 | 194 | netif_tx_lock(dev); |
1da177e4 LT |
195 | if (dev->qdisc != &noop_qdisc) { |
196 | if (netif_device_present(dev) && | |
197 | netif_running(dev) && | |
198 | netif_carrier_ok(dev)) { | |
199 | if (netif_queue_stopped(dev) && | |
338f7566 SH |
200 | time_after(jiffies, dev->trans_start + dev->watchdog_timeo)) { |
201 | ||
202 | printk(KERN_INFO "NETDEV WATCHDOG: %s: transmit timed out\n", | |
203 | dev->name); | |
1da177e4 LT |
204 | dev->tx_timeout(dev); |
205 | } | |
206 | if (!mod_timer(&dev->watchdog_timer, jiffies + dev->watchdog_timeo)) | |
207 | dev_hold(dev); | |
208 | } | |
209 | } | |
932ff279 | 210 | netif_tx_unlock(dev); |
1da177e4 LT |
211 | |
212 | dev_put(dev); | |
213 | } | |
214 | ||
215 | static void dev_watchdog_init(struct net_device *dev) | |
216 | { | |
217 | init_timer(&dev->watchdog_timer); | |
218 | dev->watchdog_timer.data = (unsigned long)dev; | |
219 | dev->watchdog_timer.function = dev_watchdog; | |
220 | } | |
221 | ||
222 | void __netdev_watchdog_up(struct net_device *dev) | |
223 | { | |
224 | if (dev->tx_timeout) { | |
225 | if (dev->watchdog_timeo <= 0) | |
226 | dev->watchdog_timeo = 5*HZ; | |
227 | if (!mod_timer(&dev->watchdog_timer, jiffies + dev->watchdog_timeo)) | |
228 | dev_hold(dev); | |
229 | } | |
230 | } | |
231 | ||
232 | static void dev_watchdog_up(struct net_device *dev) | |
233 | { | |
932ff279 | 234 | netif_tx_lock_bh(dev); |
1da177e4 | 235 | __netdev_watchdog_up(dev); |
932ff279 | 236 | netif_tx_unlock_bh(dev); |
1da177e4 LT |
237 | } |
238 | ||
239 | static void dev_watchdog_down(struct net_device *dev) | |
240 | { | |
932ff279 | 241 | netif_tx_lock_bh(dev); |
1da177e4 | 242 | if (del_timer(&dev->watchdog_timer)) |
15333061 | 243 | dev_put(dev); |
932ff279 | 244 | netif_tx_unlock_bh(dev); |
1da177e4 LT |
245 | } |
246 | ||
0a242efc DV |
247 | void netif_carrier_on(struct net_device *dev) |
248 | { | |
249 | if (test_and_clear_bit(__LINK_STATE_NOCARRIER, &dev->state)) | |
250 | linkwatch_fire_event(dev); | |
251 | if (netif_running(dev)) | |
252 | __netdev_watchdog_up(dev); | |
253 | } | |
254 | ||
255 | void netif_carrier_off(struct net_device *dev) | |
256 | { | |
257 | if (!test_and_set_bit(__LINK_STATE_NOCARRIER, &dev->state)) | |
258 | linkwatch_fire_event(dev); | |
259 | } | |
260 | ||
1da177e4 LT |
261 | /* "NOOP" scheduler: the best scheduler, recommended for all interfaces |
262 | under all circumstances. It is difficult to invent anything faster or | |
263 | cheaper. | |
264 | */ | |
265 | ||
94df109a | 266 | static int noop_enqueue(struct sk_buff *skb, struct Qdisc * qdisc) |
1da177e4 LT |
267 | { |
268 | kfree_skb(skb); | |
269 | return NET_XMIT_CN; | |
270 | } | |
271 | ||
94df109a | 272 | static struct sk_buff *noop_dequeue(struct Qdisc * qdisc) |
1da177e4 LT |
273 | { |
274 | return NULL; | |
275 | } | |
276 | ||
94df109a | 277 | static int noop_requeue(struct sk_buff *skb, struct Qdisc* qdisc) |
1da177e4 LT |
278 | { |
279 | if (net_ratelimit()) | |
94df109a TG |
280 | printk(KERN_DEBUG "%s deferred output. It is buggy.\n", |
281 | skb->dev->name); | |
1da177e4 LT |
282 | kfree_skb(skb); |
283 | return NET_XMIT_CN; | |
284 | } | |
285 | ||
286 | struct Qdisc_ops noop_qdisc_ops = { | |
1da177e4 LT |
287 | .id = "noop", |
288 | .priv_size = 0, | |
289 | .enqueue = noop_enqueue, | |
290 | .dequeue = noop_dequeue, | |
291 | .requeue = noop_requeue, | |
292 | .owner = THIS_MODULE, | |
293 | }; | |
294 | ||
295 | struct Qdisc noop_qdisc = { | |
296 | .enqueue = noop_enqueue, | |
297 | .dequeue = noop_dequeue, | |
298 | .flags = TCQ_F_BUILTIN, | |
299 | .ops = &noop_qdisc_ops, | |
300 | .list = LIST_HEAD_INIT(noop_qdisc.list), | |
301 | }; | |
302 | ||
303 | static struct Qdisc_ops noqueue_qdisc_ops = { | |
1da177e4 LT |
304 | .id = "noqueue", |
305 | .priv_size = 0, | |
306 | .enqueue = noop_enqueue, | |
307 | .dequeue = noop_dequeue, | |
308 | .requeue = noop_requeue, | |
309 | .owner = THIS_MODULE, | |
310 | }; | |
311 | ||
312 | static struct Qdisc noqueue_qdisc = { | |
313 | .enqueue = NULL, | |
314 | .dequeue = noop_dequeue, | |
315 | .flags = TCQ_F_BUILTIN, | |
316 | .ops = &noqueue_qdisc_ops, | |
317 | .list = LIST_HEAD_INIT(noqueue_qdisc.list), | |
318 | }; | |
319 | ||
320 | ||
321 | static const u8 prio2band[TC_PRIO_MAX+1] = | |
322 | { 1, 2, 2, 2, 1, 2, 0, 0 , 1, 1, 1, 1, 1, 1, 1, 1 }; | |
323 | ||
324 | /* 3-band FIFO queue: old style, but should be a bit faster than | |
325 | generic prio+fifo combination. | |
326 | */ | |
327 | ||
f87a9c3d TG |
328 | #define PFIFO_FAST_BANDS 3 |
329 | ||
321090e7 TG |
330 | static inline struct sk_buff_head *prio2list(struct sk_buff *skb, |
331 | struct Qdisc *qdisc) | |
1da177e4 LT |
332 | { |
333 | struct sk_buff_head *list = qdisc_priv(qdisc); | |
321090e7 TG |
334 | return list + prio2band[skb->priority & TC_PRIO_MAX]; |
335 | } | |
1da177e4 | 336 | |
f87a9c3d | 337 | static int pfifo_fast_enqueue(struct sk_buff *skb, struct Qdisc* qdisc) |
321090e7 TG |
338 | { |
339 | struct sk_buff_head *list = prio2list(skb, qdisc); | |
1da177e4 | 340 | |
821d24ae | 341 | if (skb_queue_len(list) < qdisc->dev->tx_queue_len) { |
1da177e4 | 342 | qdisc->q.qlen++; |
821d24ae | 343 | return __qdisc_enqueue_tail(skb, qdisc, list); |
1da177e4 | 344 | } |
821d24ae TG |
345 | |
346 | return qdisc_drop(skb, qdisc); | |
1da177e4 LT |
347 | } |
348 | ||
f87a9c3d | 349 | static struct sk_buff *pfifo_fast_dequeue(struct Qdisc* qdisc) |
1da177e4 LT |
350 | { |
351 | int prio; | |
352 | struct sk_buff_head *list = qdisc_priv(qdisc); | |
1da177e4 | 353 | |
452f299d TG |
354 | for (prio = 0; prio < PFIFO_FAST_BANDS; prio++) { |
355 | if (!skb_queue_empty(list + prio)) { | |
1da177e4 | 356 | qdisc->q.qlen--; |
452f299d | 357 | return __qdisc_dequeue_head(qdisc, list + prio); |
1da177e4 LT |
358 | } |
359 | } | |
f87a9c3d | 360 | |
1da177e4 LT |
361 | return NULL; |
362 | } | |
363 | ||
f87a9c3d | 364 | static int pfifo_fast_requeue(struct sk_buff *skb, struct Qdisc* qdisc) |
1da177e4 | 365 | { |
1da177e4 | 366 | qdisc->q.qlen++; |
321090e7 | 367 | return __qdisc_requeue(skb, qdisc, prio2list(skb, qdisc)); |
1da177e4 LT |
368 | } |
369 | ||
f87a9c3d | 370 | static void pfifo_fast_reset(struct Qdisc* qdisc) |
1da177e4 LT |
371 | { |
372 | int prio; | |
373 | struct sk_buff_head *list = qdisc_priv(qdisc); | |
374 | ||
f87a9c3d | 375 | for (prio = 0; prio < PFIFO_FAST_BANDS; prio++) |
821d24ae TG |
376 | __qdisc_reset_queue(qdisc, list + prio); |
377 | ||
378 | qdisc->qstats.backlog = 0; | |
1da177e4 LT |
379 | qdisc->q.qlen = 0; |
380 | } | |
381 | ||
382 | static int pfifo_fast_dump(struct Qdisc *qdisc, struct sk_buff *skb) | |
383 | { | |
f87a9c3d | 384 | struct tc_prio_qopt opt = { .bands = PFIFO_FAST_BANDS }; |
1da177e4 | 385 | |
1da177e4 LT |
386 | memcpy(&opt.priomap, prio2band, TC_PRIO_MAX+1); |
387 | RTA_PUT(skb, TCA_OPTIONS, sizeof(opt), &opt); | |
388 | return skb->len; | |
389 | ||
390 | rtattr_failure: | |
1da177e4 LT |
391 | return -1; |
392 | } | |
393 | ||
394 | static int pfifo_fast_init(struct Qdisc *qdisc, struct rtattr *opt) | |
395 | { | |
f87a9c3d | 396 | int prio; |
1da177e4 LT |
397 | struct sk_buff_head *list = qdisc_priv(qdisc); |
398 | ||
f87a9c3d TG |
399 | for (prio = 0; prio < PFIFO_FAST_BANDS; prio++) |
400 | skb_queue_head_init(list + prio); | |
1da177e4 LT |
401 | |
402 | return 0; | |
403 | } | |
404 | ||
405 | static struct Qdisc_ops pfifo_fast_ops = { | |
1da177e4 | 406 | .id = "pfifo_fast", |
f87a9c3d | 407 | .priv_size = PFIFO_FAST_BANDS * sizeof(struct sk_buff_head), |
1da177e4 LT |
408 | .enqueue = pfifo_fast_enqueue, |
409 | .dequeue = pfifo_fast_dequeue, | |
410 | .requeue = pfifo_fast_requeue, | |
411 | .init = pfifo_fast_init, | |
412 | .reset = pfifo_fast_reset, | |
413 | .dump = pfifo_fast_dump, | |
414 | .owner = THIS_MODULE, | |
415 | }; | |
416 | ||
3d54b82f | 417 | struct Qdisc *qdisc_alloc(struct net_device *dev, struct Qdisc_ops *ops) |
1da177e4 LT |
418 | { |
419 | void *p; | |
420 | struct Qdisc *sch; | |
3d54b82f TG |
421 | unsigned int size; |
422 | int err = -ENOBUFS; | |
1da177e4 LT |
423 | |
424 | /* ensure that the Qdisc and the private data are 32-byte aligned */ | |
3d54b82f TG |
425 | size = QDISC_ALIGN(sizeof(*sch)); |
426 | size += ops->priv_size + (QDISC_ALIGNTO - 1); | |
1da177e4 LT |
427 | |
428 | p = kmalloc(size, GFP_KERNEL); | |
429 | if (!p) | |
3d54b82f | 430 | goto errout; |
1da177e4 | 431 | memset(p, 0, size); |
3d54b82f TG |
432 | sch = (struct Qdisc *) QDISC_ALIGN((unsigned long) p); |
433 | sch->padded = (char *) sch - (char *) p; | |
1da177e4 LT |
434 | |
435 | INIT_LIST_HEAD(&sch->list); | |
436 | skb_queue_head_init(&sch->q); | |
437 | sch->ops = ops; | |
438 | sch->enqueue = ops->enqueue; | |
439 | sch->dequeue = ops->dequeue; | |
440 | sch->dev = dev; | |
441 | dev_hold(dev); | |
442 | sch->stats_lock = &dev->queue_lock; | |
443 | atomic_set(&sch->refcnt, 1); | |
3d54b82f TG |
444 | |
445 | return sch; | |
446 | errout: | |
447 | return ERR_PTR(-err); | |
448 | } | |
449 | ||
450 | struct Qdisc * qdisc_create_dflt(struct net_device *dev, struct Qdisc_ops *ops) | |
451 | { | |
452 | struct Qdisc *sch; | |
453 | ||
454 | sch = qdisc_alloc(dev, ops); | |
455 | if (IS_ERR(sch)) | |
456 | goto errout; | |
457 | ||
1da177e4 LT |
458 | if (!ops->init || ops->init(sch, NULL) == 0) |
459 | return sch; | |
460 | ||
0fbbeb1b | 461 | qdisc_destroy(sch); |
3d54b82f | 462 | errout: |
1da177e4 LT |
463 | return NULL; |
464 | } | |
465 | ||
466 | /* Under dev->queue_lock and BH! */ | |
467 | ||
468 | void qdisc_reset(struct Qdisc *qdisc) | |
469 | { | |
470 | struct Qdisc_ops *ops = qdisc->ops; | |
471 | ||
472 | if (ops->reset) | |
473 | ops->reset(qdisc); | |
474 | } | |
475 | ||
476 | /* this is the rcu callback function to clean up a qdisc when there | |
477 | * are no further references to it */ | |
478 | ||
479 | static void __qdisc_destroy(struct rcu_head *head) | |
480 | { | |
481 | struct Qdisc *qdisc = container_of(head, struct Qdisc, q_rcu); | |
482 | struct Qdisc_ops *ops = qdisc->ops; | |
483 | ||
484 | #ifdef CONFIG_NET_ESTIMATOR | |
485 | gen_kill_estimator(&qdisc->bstats, &qdisc->rate_est); | |
486 | #endif | |
487 | write_lock(&qdisc_tree_lock); | |
488 | if (ops->reset) | |
489 | ops->reset(qdisc); | |
490 | if (ops->destroy) | |
491 | ops->destroy(qdisc); | |
492 | write_unlock(&qdisc_tree_lock); | |
493 | module_put(ops->owner); | |
494 | ||
495 | dev_put(qdisc->dev); | |
496 | kfree((char *) qdisc - qdisc->padded); | |
497 | } | |
498 | ||
499 | /* Under dev->queue_lock and BH! */ | |
500 | ||
501 | void qdisc_destroy(struct Qdisc *qdisc) | |
502 | { | |
503 | struct list_head cql = LIST_HEAD_INIT(cql); | |
504 | struct Qdisc *cq, *q, *n; | |
505 | ||
506 | if (qdisc->flags & TCQ_F_BUILTIN || | |
507 | !atomic_dec_and_test(&qdisc->refcnt)) | |
508 | return; | |
509 | ||
510 | if (!list_empty(&qdisc->list)) { | |
511 | if (qdisc->ops->cl_ops == NULL) | |
512 | list_del(&qdisc->list); | |
513 | else | |
514 | list_move(&qdisc->list, &cql); | |
515 | } | |
516 | ||
517 | /* unlink inner qdiscs from dev->qdisc_list immediately */ | |
518 | list_for_each_entry(cq, &cql, list) | |
519 | list_for_each_entry_safe(q, n, &qdisc->dev->qdisc_list, list) | |
520 | if (TC_H_MAJ(q->parent) == TC_H_MAJ(cq->handle)) { | |
521 | if (q->ops->cl_ops == NULL) | |
522 | list_del_init(&q->list); | |
523 | else | |
524 | list_move_tail(&q->list, &cql); | |
525 | } | |
526 | list_for_each_entry_safe(cq, n, &cql, list) | |
527 | list_del_init(&cq->list); | |
528 | ||
529 | call_rcu(&qdisc->q_rcu, __qdisc_destroy); | |
530 | } | |
531 | ||
532 | void dev_activate(struct net_device *dev) | |
533 | { | |
534 | /* No queueing discipline is attached to device; | |
535 | create default one i.e. pfifo_fast for devices, | |
536 | which need queueing and noqueue_qdisc for | |
537 | virtual interfaces | |
538 | */ | |
539 | ||
540 | if (dev->qdisc_sleeping == &noop_qdisc) { | |
541 | struct Qdisc *qdisc; | |
542 | if (dev->tx_queue_len) { | |
543 | qdisc = qdisc_create_dflt(dev, &pfifo_fast_ops); | |
544 | if (qdisc == NULL) { | |
545 | printk(KERN_INFO "%s: activation failed\n", dev->name); | |
546 | return; | |
547 | } | |
548 | write_lock_bh(&qdisc_tree_lock); | |
549 | list_add_tail(&qdisc->list, &dev->qdisc_list); | |
550 | write_unlock_bh(&qdisc_tree_lock); | |
551 | } else { | |
552 | qdisc = &noqueue_qdisc; | |
553 | } | |
554 | write_lock_bh(&qdisc_tree_lock); | |
555 | dev->qdisc_sleeping = qdisc; | |
556 | write_unlock_bh(&qdisc_tree_lock); | |
557 | } | |
558 | ||
cacaddf5 TC |
559 | if (!netif_carrier_ok(dev)) |
560 | /* Delay activation until next carrier-on event */ | |
561 | return; | |
562 | ||
1da177e4 LT |
563 | spin_lock_bh(&dev->queue_lock); |
564 | rcu_assign_pointer(dev->qdisc, dev->qdisc_sleeping); | |
565 | if (dev->qdisc != &noqueue_qdisc) { | |
566 | dev->trans_start = jiffies; | |
567 | dev_watchdog_up(dev); | |
568 | } | |
569 | spin_unlock_bh(&dev->queue_lock); | |
570 | } | |
571 | ||
572 | void dev_deactivate(struct net_device *dev) | |
573 | { | |
574 | struct Qdisc *qdisc; | |
575 | ||
576 | spin_lock_bh(&dev->queue_lock); | |
577 | qdisc = dev->qdisc; | |
578 | dev->qdisc = &noop_qdisc; | |
579 | ||
580 | qdisc_reset(qdisc); | |
581 | ||
582 | spin_unlock_bh(&dev->queue_lock); | |
583 | ||
584 | dev_watchdog_down(dev); | |
585 | ||
586 | while (test_bit(__LINK_STATE_SCHED, &dev->state)) | |
587 | yield(); | |
588 | ||
932ff279 | 589 | spin_unlock_wait(&dev->_xmit_lock); |
1da177e4 LT |
590 | } |
591 | ||
592 | void dev_init_scheduler(struct net_device *dev) | |
593 | { | |
594 | qdisc_lock_tree(dev); | |
595 | dev->qdisc = &noop_qdisc; | |
596 | dev->qdisc_sleeping = &noop_qdisc; | |
597 | INIT_LIST_HEAD(&dev->qdisc_list); | |
598 | qdisc_unlock_tree(dev); | |
599 | ||
600 | dev_watchdog_init(dev); | |
601 | } | |
602 | ||
603 | void dev_shutdown(struct net_device *dev) | |
604 | { | |
605 | struct Qdisc *qdisc; | |
606 | ||
607 | qdisc_lock_tree(dev); | |
608 | qdisc = dev->qdisc_sleeping; | |
609 | dev->qdisc = &noop_qdisc; | |
610 | dev->qdisc_sleeping = &noop_qdisc; | |
611 | qdisc_destroy(qdisc); | |
612 | #if defined(CONFIG_NET_SCH_INGRESS) || defined(CONFIG_NET_SCH_INGRESS_MODULE) | |
613 | if ((qdisc = dev->qdisc_ingress) != NULL) { | |
614 | dev->qdisc_ingress = NULL; | |
615 | qdisc_destroy(qdisc); | |
616 | } | |
617 | #endif | |
618 | BUG_TRAP(!timer_pending(&dev->watchdog_timer)); | |
619 | qdisc_unlock_tree(dev); | |
620 | } | |
621 | ||
622 | EXPORT_SYMBOL(__netdev_watchdog_up); | |
0a242efc DV |
623 | EXPORT_SYMBOL(netif_carrier_on); |
624 | EXPORT_SYMBOL(netif_carrier_off); | |
1da177e4 LT |
625 | EXPORT_SYMBOL(noop_qdisc); |
626 | EXPORT_SYMBOL(noop_qdisc_ops); | |
627 | EXPORT_SYMBOL(qdisc_create_dflt); | |
3d54b82f | 628 | EXPORT_SYMBOL(qdisc_alloc); |
1da177e4 LT |
629 | EXPORT_SYMBOL(qdisc_destroy); |
630 | EXPORT_SYMBOL(qdisc_reset); | |
1da177e4 LT |
631 | EXPORT_SYMBOL(qdisc_lock_tree); |
632 | EXPORT_SYMBOL(qdisc_unlock_tree); |