Commit | Line | Data |
---|---|---|
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> | |
1da177e4 LT |
17 | #include <linux/module.h> |
18 | #include <linux/types.h> | |
19 | #include <linux/kernel.h> | |
20 | #include <linux/sched.h> | |
21 | #include <linux/string.h> | |
22 | #include <linux/mm.h> | |
23 | #include <linux/socket.h> | |
24 | #include <linux/sockios.h> | |
25 | #include <linux/in.h> | |
26 | #include <linux/errno.h> | |
27 | #include <linux/interrupt.h> | |
28 | #include <linux/netdevice.h> | |
29 | #include <linux/skbuff.h> | |
30 | #include <linux/rtnetlink.h> | |
31 | #include <linux/init.h> | |
32 | #include <linux/rcupdate.h> | |
33 | #include <linux/list.h> | |
34 | #include <net/sock.h> | |
35 | #include <net/pkt_sched.h> | |
36 | ||
37 | /* Main transmission queue. */ | |
38 | ||
0463d4ae PM |
39 | /* Modifications to data participating in scheduling must be protected with |
40 | * dev->queue_lock spinlock. | |
41 | * | |
42 | * The idea is the following: | |
43 | * - enqueue, dequeue are serialized via top level device | |
44 | * spinlock dev->queue_lock. | |
fd44de7c PM |
45 | * - ingress filtering is serialized via top level device |
46 | * spinlock dev->ingress_lock. | |
0463d4ae | 47 | * - updates to tree and tree walking are only done under the rtnl mutex. |
1da177e4 | 48 | */ |
1da177e4 LT |
49 | |
50 | void qdisc_lock_tree(struct net_device *dev) | |
51 | { | |
1da177e4 | 52 | spin_lock_bh(&dev->queue_lock); |
fd44de7c | 53 | spin_lock(&dev->ingress_lock); |
1da177e4 LT |
54 | } |
55 | ||
56 | void qdisc_unlock_tree(struct net_device *dev) | |
57 | { | |
fd44de7c | 58 | spin_unlock(&dev->ingress_lock); |
1da177e4 | 59 | spin_unlock_bh(&dev->queue_lock); |
1da177e4 LT |
60 | } |
61 | ||
10297b99 | 62 | /* |
1da177e4 LT |
63 | dev->queue_lock serializes queue accesses for this device |
64 | AND dev->qdisc pointer itself. | |
65 | ||
932ff279 | 66 | netif_tx_lock serializes accesses to device driver. |
1da177e4 | 67 | |
932ff279 | 68 | dev->queue_lock and netif_tx_lock are mutually exclusive, |
1da177e4 LT |
69 | if one is grabbed, another must be free. |
70 | */ | |
71 | ||
72 | ||
73 | /* Kick device. | |
74 | Note, that this procedure can be called by a watchdog timer, so that | |
75 | we do not check dev->tbusy flag here. | |
76 | ||
77 | Returns: 0 - queue is empty. | |
10297b99 | 78 | >0 - queue is not empty, but throttled. |
1da177e4 LT |
79 | <0 - queue is not empty. Device is throttled, if dev->tbusy != 0. |
80 | ||
81 | NOTE: Called under dev->queue_lock with locally disabled BH. | |
82 | */ | |
83 | ||
48d83325 | 84 | static inline int qdisc_restart(struct net_device *dev) |
1da177e4 LT |
85 | { |
86 | struct Qdisc *q = dev->qdisc; | |
87 | struct sk_buff *skb; | |
88 | ||
89 | /* Dequeue packet */ | |
f6a78bfc | 90 | if (((skb = dev->gso_skb)) || ((skb = q->dequeue(q)))) { |
1da177e4 | 91 | unsigned nolock = (dev->features & NETIF_F_LLTX); |
f6a78bfc HX |
92 | |
93 | dev->gso_skb = NULL; | |
94 | ||
1da177e4 LT |
95 | /* |
96 | * When the driver has LLTX set it does its own locking | |
97 | * in start_xmit. No need to add additional overhead by | |
98 | * locking again. These checks are worth it because | |
99 | * even uncongested locks can be quite expensive. | |
100 | * The driver can do trylock like here too, in case | |
101 | * of lock congestion it should return -1 and the packet | |
102 | * will be requeued. | |
103 | */ | |
104 | if (!nolock) { | |
932ff279 | 105 | if (!netif_tx_trylock(dev)) { |
1da177e4 LT |
106 | collision: |
107 | /* So, someone grabbed the driver. */ | |
10297b99 | 108 | |
1da177e4 LT |
109 | /* It may be transient configuration error, |
110 | when hard_start_xmit() recurses. We detect | |
111 | it by checking xmit owner and drop the | |
112 | packet when deadloop is detected. | |
113 | */ | |
114 | if (dev->xmit_lock_owner == smp_processor_id()) { | |
115 | kfree_skb(skb); | |
116 | if (net_ratelimit()) | |
117 | printk(KERN_DEBUG "Dead loop on netdevice %s, fix it urgently!\n", dev->name); | |
118 | return -1; | |
119 | } | |
120 | __get_cpu_var(netdev_rx_stat).cpu_collision++; | |
121 | goto requeue; | |
122 | } | |
1da177e4 | 123 | } |
10297b99 | 124 | |
1da177e4 LT |
125 | { |
126 | /* And release queue */ | |
127 | spin_unlock(&dev->queue_lock); | |
128 | ||
129 | if (!netif_queue_stopped(dev)) { | |
130 | int ret; | |
1da177e4 | 131 | |
f6a78bfc | 132 | ret = dev_hard_start_xmit(skb, dev); |
10297b99 | 133 | if (ret == NETDEV_TX_OK) { |
1da177e4 | 134 | if (!nolock) { |
932ff279 | 135 | netif_tx_unlock(dev); |
1da177e4 LT |
136 | } |
137 | spin_lock(&dev->queue_lock); | |
138 | return -1; | |
139 | } | |
140 | if (ret == NETDEV_TX_LOCKED && nolock) { | |
141 | spin_lock(&dev->queue_lock); | |
10297b99 | 142 | goto collision; |
1da177e4 LT |
143 | } |
144 | } | |
145 | ||
146 | /* NETDEV_TX_BUSY - we need to requeue */ | |
147 | /* Release the driver */ | |
10297b99 | 148 | if (!nolock) { |
932ff279 | 149 | netif_tx_unlock(dev); |
10297b99 | 150 | } |
1da177e4 LT |
151 | spin_lock(&dev->queue_lock); |
152 | q = dev->qdisc; | |
153 | } | |
154 | ||
155 | /* Device kicked us out :( | |
156 | This is possible in three cases: | |
157 | ||
158 | 0. driver is locked | |
159 | 1. fastroute is enabled | |
160 | 2. device cannot determine busy state | |
161 | before start of transmission (f.e. dialout) | |
162 | 3. device is buggy (ppp) | |
163 | */ | |
164 | ||
165 | requeue: | |
f6a78bfc HX |
166 | if (skb->next) |
167 | dev->gso_skb = skb; | |
168 | else | |
169 | q->ops->requeue(skb, q); | |
1da177e4 LT |
170 | netif_schedule(dev); |
171 | return 1; | |
172 | } | |
8cbe1d46 | 173 | BUG_ON((int) q->q.qlen < 0); |
1da177e4 LT |
174 | return q->q.qlen; |
175 | } | |
176 | ||
48d83325 HX |
177 | void __qdisc_run(struct net_device *dev) |
178 | { | |
d4828d85 HX |
179 | if (unlikely(dev->qdisc == &noop_qdisc)) |
180 | goto out; | |
181 | ||
48d83325 HX |
182 | while (qdisc_restart(dev) < 0 && !netif_queue_stopped(dev)) |
183 | /* NOTHING */; | |
184 | ||
d4828d85 | 185 | out: |
48d83325 HX |
186 | clear_bit(__LINK_STATE_QDISC_RUNNING, &dev->state); |
187 | } | |
188 | ||
1da177e4 LT |
189 | static void dev_watchdog(unsigned long arg) |
190 | { | |
191 | struct net_device *dev = (struct net_device *)arg; | |
192 | ||
932ff279 | 193 | netif_tx_lock(dev); |
1da177e4 LT |
194 | if (dev->qdisc != &noop_qdisc) { |
195 | if (netif_device_present(dev) && | |
196 | netif_running(dev) && | |
197 | netif_carrier_ok(dev)) { | |
198 | if (netif_queue_stopped(dev) && | |
338f7566 SH |
199 | time_after(jiffies, dev->trans_start + dev->watchdog_timeo)) { |
200 | ||
201 | printk(KERN_INFO "NETDEV WATCHDOG: %s: transmit timed out\n", | |
202 | dev->name); | |
1da177e4 LT |
203 | dev->tx_timeout(dev); |
204 | } | |
f5a6e01c | 205 | if (!mod_timer(&dev->watchdog_timer, round_jiffies(jiffies + dev->watchdog_timeo))) |
1da177e4 LT |
206 | dev_hold(dev); |
207 | } | |
208 | } | |
932ff279 | 209 | netif_tx_unlock(dev); |
1da177e4 LT |
210 | |
211 | dev_put(dev); | |
212 | } | |
213 | ||
214 | static void dev_watchdog_init(struct net_device *dev) | |
215 | { | |
216 | init_timer(&dev->watchdog_timer); | |
217 | dev->watchdog_timer.data = (unsigned long)dev; | |
218 | dev->watchdog_timer.function = dev_watchdog; | |
219 | } | |
220 | ||
221 | void __netdev_watchdog_up(struct net_device *dev) | |
222 | { | |
223 | if (dev->tx_timeout) { | |
224 | if (dev->watchdog_timeo <= 0) | |
225 | dev->watchdog_timeo = 5*HZ; | |
226 | if (!mod_timer(&dev->watchdog_timer, jiffies + dev->watchdog_timeo)) | |
227 | dev_hold(dev); | |
228 | } | |
229 | } | |
230 | ||
231 | static void dev_watchdog_up(struct net_device *dev) | |
232 | { | |
1da177e4 | 233 | __netdev_watchdog_up(dev); |
1da177e4 LT |
234 | } |
235 | ||
236 | static void dev_watchdog_down(struct net_device *dev) | |
237 | { | |
932ff279 | 238 | netif_tx_lock_bh(dev); |
1da177e4 | 239 | if (del_timer(&dev->watchdog_timer)) |
15333061 | 240 | dev_put(dev); |
932ff279 | 241 | netif_tx_unlock_bh(dev); |
1da177e4 LT |
242 | } |
243 | ||
0a242efc DV |
244 | void netif_carrier_on(struct net_device *dev) |
245 | { | |
246 | if (test_and_clear_bit(__LINK_STATE_NOCARRIER, &dev->state)) | |
247 | linkwatch_fire_event(dev); | |
248 | if (netif_running(dev)) | |
249 | __netdev_watchdog_up(dev); | |
250 | } | |
251 | ||
252 | void netif_carrier_off(struct net_device *dev) | |
253 | { | |
254 | if (!test_and_set_bit(__LINK_STATE_NOCARRIER, &dev->state)) | |
255 | linkwatch_fire_event(dev); | |
256 | } | |
257 | ||
1da177e4 LT |
258 | /* "NOOP" scheduler: the best scheduler, recommended for all interfaces |
259 | under all circumstances. It is difficult to invent anything faster or | |
260 | cheaper. | |
261 | */ | |
262 | ||
94df109a | 263 | static int noop_enqueue(struct sk_buff *skb, struct Qdisc * qdisc) |
1da177e4 LT |
264 | { |
265 | kfree_skb(skb); | |
266 | return NET_XMIT_CN; | |
267 | } | |
268 | ||
94df109a | 269 | static struct sk_buff *noop_dequeue(struct Qdisc * qdisc) |
1da177e4 LT |
270 | { |
271 | return NULL; | |
272 | } | |
273 | ||
94df109a | 274 | static int noop_requeue(struct sk_buff *skb, struct Qdisc* qdisc) |
1da177e4 LT |
275 | { |
276 | if (net_ratelimit()) | |
94df109a TG |
277 | printk(KERN_DEBUG "%s deferred output. It is buggy.\n", |
278 | skb->dev->name); | |
1da177e4 LT |
279 | kfree_skb(skb); |
280 | return NET_XMIT_CN; | |
281 | } | |
282 | ||
283 | struct Qdisc_ops noop_qdisc_ops = { | |
1da177e4 LT |
284 | .id = "noop", |
285 | .priv_size = 0, | |
286 | .enqueue = noop_enqueue, | |
287 | .dequeue = noop_dequeue, | |
288 | .requeue = noop_requeue, | |
289 | .owner = THIS_MODULE, | |
290 | }; | |
291 | ||
292 | struct Qdisc noop_qdisc = { | |
293 | .enqueue = noop_enqueue, | |
294 | .dequeue = noop_dequeue, | |
295 | .flags = TCQ_F_BUILTIN, | |
10297b99 | 296 | .ops = &noop_qdisc_ops, |
1da177e4 LT |
297 | .list = LIST_HEAD_INIT(noop_qdisc.list), |
298 | }; | |
299 | ||
300 | static struct Qdisc_ops noqueue_qdisc_ops = { | |
1da177e4 LT |
301 | .id = "noqueue", |
302 | .priv_size = 0, | |
303 | .enqueue = noop_enqueue, | |
304 | .dequeue = noop_dequeue, | |
305 | .requeue = noop_requeue, | |
306 | .owner = THIS_MODULE, | |
307 | }; | |
308 | ||
309 | static struct Qdisc noqueue_qdisc = { | |
310 | .enqueue = NULL, | |
311 | .dequeue = noop_dequeue, | |
312 | .flags = TCQ_F_BUILTIN, | |
313 | .ops = &noqueue_qdisc_ops, | |
314 | .list = LIST_HEAD_INIT(noqueue_qdisc.list), | |
315 | }; | |
316 | ||
317 | ||
318 | static const u8 prio2band[TC_PRIO_MAX+1] = | |
319 | { 1, 2, 2, 2, 1, 2, 0, 0 , 1, 1, 1, 1, 1, 1, 1, 1 }; | |
320 | ||
321 | /* 3-band FIFO queue: old style, but should be a bit faster than | |
322 | generic prio+fifo combination. | |
323 | */ | |
324 | ||
f87a9c3d TG |
325 | #define PFIFO_FAST_BANDS 3 |
326 | ||
321090e7 TG |
327 | static inline struct sk_buff_head *prio2list(struct sk_buff *skb, |
328 | struct Qdisc *qdisc) | |
1da177e4 LT |
329 | { |
330 | struct sk_buff_head *list = qdisc_priv(qdisc); | |
321090e7 TG |
331 | return list + prio2band[skb->priority & TC_PRIO_MAX]; |
332 | } | |
1da177e4 | 333 | |
f87a9c3d | 334 | static int pfifo_fast_enqueue(struct sk_buff *skb, struct Qdisc* qdisc) |
321090e7 TG |
335 | { |
336 | struct sk_buff_head *list = prio2list(skb, qdisc); | |
1da177e4 | 337 | |
821d24ae | 338 | if (skb_queue_len(list) < qdisc->dev->tx_queue_len) { |
1da177e4 | 339 | qdisc->q.qlen++; |
821d24ae | 340 | return __qdisc_enqueue_tail(skb, qdisc, list); |
1da177e4 | 341 | } |
821d24ae TG |
342 | |
343 | return qdisc_drop(skb, qdisc); | |
1da177e4 LT |
344 | } |
345 | ||
f87a9c3d | 346 | static struct sk_buff *pfifo_fast_dequeue(struct Qdisc* qdisc) |
1da177e4 LT |
347 | { |
348 | int prio; | |
349 | struct sk_buff_head *list = qdisc_priv(qdisc); | |
1da177e4 | 350 | |
452f299d TG |
351 | for (prio = 0; prio < PFIFO_FAST_BANDS; prio++) { |
352 | if (!skb_queue_empty(list + prio)) { | |
1da177e4 | 353 | qdisc->q.qlen--; |
452f299d | 354 | return __qdisc_dequeue_head(qdisc, list + prio); |
1da177e4 LT |
355 | } |
356 | } | |
f87a9c3d | 357 | |
1da177e4 LT |
358 | return NULL; |
359 | } | |
360 | ||
f87a9c3d | 361 | static int pfifo_fast_requeue(struct sk_buff *skb, struct Qdisc* qdisc) |
1da177e4 | 362 | { |
1da177e4 | 363 | qdisc->q.qlen++; |
321090e7 | 364 | return __qdisc_requeue(skb, qdisc, prio2list(skb, qdisc)); |
1da177e4 LT |
365 | } |
366 | ||
f87a9c3d | 367 | static void pfifo_fast_reset(struct Qdisc* qdisc) |
1da177e4 LT |
368 | { |
369 | int prio; | |
370 | struct sk_buff_head *list = qdisc_priv(qdisc); | |
371 | ||
f87a9c3d | 372 | for (prio = 0; prio < PFIFO_FAST_BANDS; prio++) |
821d24ae TG |
373 | __qdisc_reset_queue(qdisc, list + prio); |
374 | ||
375 | qdisc->qstats.backlog = 0; | |
1da177e4 LT |
376 | qdisc->q.qlen = 0; |
377 | } | |
378 | ||
379 | static int pfifo_fast_dump(struct Qdisc *qdisc, struct sk_buff *skb) | |
380 | { | |
f87a9c3d | 381 | struct tc_prio_qopt opt = { .bands = PFIFO_FAST_BANDS }; |
1da177e4 | 382 | |
1da177e4 LT |
383 | memcpy(&opt.priomap, prio2band, TC_PRIO_MAX+1); |
384 | RTA_PUT(skb, TCA_OPTIONS, sizeof(opt), &opt); | |
385 | return skb->len; | |
386 | ||
387 | rtattr_failure: | |
1da177e4 LT |
388 | return -1; |
389 | } | |
390 | ||
391 | static int pfifo_fast_init(struct Qdisc *qdisc, struct rtattr *opt) | |
392 | { | |
f87a9c3d | 393 | int prio; |
1da177e4 LT |
394 | struct sk_buff_head *list = qdisc_priv(qdisc); |
395 | ||
f87a9c3d TG |
396 | for (prio = 0; prio < PFIFO_FAST_BANDS; prio++) |
397 | skb_queue_head_init(list + prio); | |
1da177e4 LT |
398 | |
399 | return 0; | |
400 | } | |
401 | ||
402 | static struct Qdisc_ops pfifo_fast_ops = { | |
1da177e4 | 403 | .id = "pfifo_fast", |
f87a9c3d | 404 | .priv_size = PFIFO_FAST_BANDS * sizeof(struct sk_buff_head), |
1da177e4 LT |
405 | .enqueue = pfifo_fast_enqueue, |
406 | .dequeue = pfifo_fast_dequeue, | |
407 | .requeue = pfifo_fast_requeue, | |
408 | .init = pfifo_fast_init, | |
409 | .reset = pfifo_fast_reset, | |
410 | .dump = pfifo_fast_dump, | |
411 | .owner = THIS_MODULE, | |
412 | }; | |
413 | ||
3d54b82f | 414 | struct Qdisc *qdisc_alloc(struct net_device *dev, struct Qdisc_ops *ops) |
1da177e4 LT |
415 | { |
416 | void *p; | |
417 | struct Qdisc *sch; | |
3d54b82f TG |
418 | unsigned int size; |
419 | int err = -ENOBUFS; | |
1da177e4 LT |
420 | |
421 | /* ensure that the Qdisc and the private data are 32-byte aligned */ | |
3d54b82f TG |
422 | size = QDISC_ALIGN(sizeof(*sch)); |
423 | size += ops->priv_size + (QDISC_ALIGNTO - 1); | |
1da177e4 | 424 | |
0da974f4 | 425 | p = kzalloc(size, GFP_KERNEL); |
1da177e4 | 426 | if (!p) |
3d54b82f | 427 | goto errout; |
3d54b82f TG |
428 | sch = (struct Qdisc *) QDISC_ALIGN((unsigned long) p); |
429 | sch->padded = (char *) sch - (char *) p; | |
1da177e4 LT |
430 | |
431 | INIT_LIST_HEAD(&sch->list); | |
432 | skb_queue_head_init(&sch->q); | |
433 | sch->ops = ops; | |
434 | sch->enqueue = ops->enqueue; | |
435 | sch->dequeue = ops->dequeue; | |
436 | sch->dev = dev; | |
437 | dev_hold(dev); | |
1da177e4 | 438 | atomic_set(&sch->refcnt, 1); |
3d54b82f TG |
439 | |
440 | return sch; | |
441 | errout: | |
442 | return ERR_PTR(-err); | |
443 | } | |
444 | ||
9f9afec4 PM |
445 | struct Qdisc * qdisc_create_dflt(struct net_device *dev, struct Qdisc_ops *ops, |
446 | unsigned int parentid) | |
3d54b82f TG |
447 | { |
448 | struct Qdisc *sch; | |
10297b99 | 449 | |
3d54b82f TG |
450 | sch = qdisc_alloc(dev, ops); |
451 | if (IS_ERR(sch)) | |
452 | goto errout; | |
fd44de7c | 453 | sch->stats_lock = &dev->queue_lock; |
9f9afec4 | 454 | sch->parent = parentid; |
3d54b82f | 455 | |
1da177e4 LT |
456 | if (!ops->init || ops->init(sch, NULL) == 0) |
457 | return sch; | |
458 | ||
0fbbeb1b | 459 | qdisc_destroy(sch); |
3d54b82f | 460 | errout: |
1da177e4 LT |
461 | return NULL; |
462 | } | |
463 | ||
464 | /* Under dev->queue_lock and BH! */ | |
465 | ||
466 | void qdisc_reset(struct Qdisc *qdisc) | |
467 | { | |
468 | struct Qdisc_ops *ops = qdisc->ops; | |
469 | ||
470 | if (ops->reset) | |
471 | ops->reset(qdisc); | |
472 | } | |
473 | ||
10297b99 | 474 | /* this is the rcu callback function to clean up a qdisc when there |
1da177e4 LT |
475 | * are no further references to it */ |
476 | ||
477 | static void __qdisc_destroy(struct rcu_head *head) | |
478 | { | |
479 | struct Qdisc *qdisc = container_of(head, struct Qdisc, q_rcu); | |
1da177e4 LT |
480 | kfree((char *) qdisc - qdisc->padded); |
481 | } | |
482 | ||
483 | /* Under dev->queue_lock and BH! */ | |
484 | ||
485 | void qdisc_destroy(struct Qdisc *qdisc) | |
486 | { | |
85670cc1 | 487 | struct Qdisc_ops *ops = qdisc->ops; |
1da177e4 LT |
488 | |
489 | if (qdisc->flags & TCQ_F_BUILTIN || | |
85670cc1 | 490 | !atomic_dec_and_test(&qdisc->refcnt)) |
1da177e4 LT |
491 | return; |
492 | ||
85670cc1 PM |
493 | list_del(&qdisc->list); |
494 | #ifdef CONFIG_NET_ESTIMATOR | |
495 | gen_kill_estimator(&qdisc->bstats, &qdisc->rate_est); | |
496 | #endif | |
497 | if (ops->reset) | |
498 | ops->reset(qdisc); | |
499 | if (ops->destroy) | |
500 | ops->destroy(qdisc); | |
1da177e4 | 501 | |
85670cc1 PM |
502 | module_put(ops->owner); |
503 | dev_put(qdisc->dev); | |
1da177e4 LT |
504 | call_rcu(&qdisc->q_rcu, __qdisc_destroy); |
505 | } | |
506 | ||
507 | void dev_activate(struct net_device *dev) | |
508 | { | |
509 | /* No queueing discipline is attached to device; | |
510 | create default one i.e. pfifo_fast for devices, | |
511 | which need queueing and noqueue_qdisc for | |
512 | virtual interfaces | |
513 | */ | |
514 | ||
515 | if (dev->qdisc_sleeping == &noop_qdisc) { | |
516 | struct Qdisc *qdisc; | |
517 | if (dev->tx_queue_len) { | |
9f9afec4 PM |
518 | qdisc = qdisc_create_dflt(dev, &pfifo_fast_ops, |
519 | TC_H_ROOT); | |
1da177e4 LT |
520 | if (qdisc == NULL) { |
521 | printk(KERN_INFO "%s: activation failed\n", dev->name); | |
522 | return; | |
523 | } | |
1da177e4 | 524 | list_add_tail(&qdisc->list, &dev->qdisc_list); |
1da177e4 LT |
525 | } else { |
526 | qdisc = &noqueue_qdisc; | |
527 | } | |
1da177e4 | 528 | dev->qdisc_sleeping = qdisc; |
1da177e4 LT |
529 | } |
530 | ||
cacaddf5 TC |
531 | if (!netif_carrier_ok(dev)) |
532 | /* Delay activation until next carrier-on event */ | |
533 | return; | |
534 | ||
1da177e4 LT |
535 | spin_lock_bh(&dev->queue_lock); |
536 | rcu_assign_pointer(dev->qdisc, dev->qdisc_sleeping); | |
537 | if (dev->qdisc != &noqueue_qdisc) { | |
538 | dev->trans_start = jiffies; | |
539 | dev_watchdog_up(dev); | |
540 | } | |
541 | spin_unlock_bh(&dev->queue_lock); | |
542 | } | |
543 | ||
544 | void dev_deactivate(struct net_device *dev) | |
545 | { | |
546 | struct Qdisc *qdisc; | |
547 | ||
548 | spin_lock_bh(&dev->queue_lock); | |
549 | qdisc = dev->qdisc; | |
550 | dev->qdisc = &noop_qdisc; | |
551 | ||
552 | qdisc_reset(qdisc); | |
553 | ||
554 | spin_unlock_bh(&dev->queue_lock); | |
555 | ||
556 | dev_watchdog_down(dev); | |
557 | ||
d4828d85 HX |
558 | /* Wait for outstanding dev_queue_xmit calls. */ |
559 | synchronize_rcu(); | |
1da177e4 | 560 | |
d4828d85 HX |
561 | /* Wait for outstanding qdisc_run calls. */ |
562 | while (test_bit(__LINK_STATE_QDISC_RUNNING, &dev->state)) | |
563 | yield(); | |
f6a78bfc HX |
564 | |
565 | if (dev->gso_skb) { | |
566 | kfree_skb(dev->gso_skb); | |
567 | dev->gso_skb = NULL; | |
568 | } | |
1da177e4 LT |
569 | } |
570 | ||
571 | void dev_init_scheduler(struct net_device *dev) | |
572 | { | |
573 | qdisc_lock_tree(dev); | |
574 | dev->qdisc = &noop_qdisc; | |
575 | dev->qdisc_sleeping = &noop_qdisc; | |
576 | INIT_LIST_HEAD(&dev->qdisc_list); | |
577 | qdisc_unlock_tree(dev); | |
578 | ||
579 | dev_watchdog_init(dev); | |
580 | } | |
581 | ||
582 | void dev_shutdown(struct net_device *dev) | |
583 | { | |
584 | struct Qdisc *qdisc; | |
585 | ||
586 | qdisc_lock_tree(dev); | |
587 | qdisc = dev->qdisc_sleeping; | |
588 | dev->qdisc = &noop_qdisc; | |
589 | dev->qdisc_sleeping = &noop_qdisc; | |
590 | qdisc_destroy(qdisc); | |
591 | #if defined(CONFIG_NET_SCH_INGRESS) || defined(CONFIG_NET_SCH_INGRESS_MODULE) | |
10297b99 | 592 | if ((qdisc = dev->qdisc_ingress) != NULL) { |
1da177e4 LT |
593 | dev->qdisc_ingress = NULL; |
594 | qdisc_destroy(qdisc); | |
10297b99 | 595 | } |
1da177e4 LT |
596 | #endif |
597 | BUG_TRAP(!timer_pending(&dev->watchdog_timer)); | |
598 | qdisc_unlock_tree(dev); | |
599 | } | |
600 | ||
0a242efc DV |
601 | EXPORT_SYMBOL(netif_carrier_on); |
602 | EXPORT_SYMBOL(netif_carrier_off); | |
1da177e4 | 603 | EXPORT_SYMBOL(noop_qdisc); |
1da177e4 LT |
604 | EXPORT_SYMBOL(qdisc_create_dflt); |
605 | EXPORT_SYMBOL(qdisc_destroy); | |
606 | EXPORT_SYMBOL(qdisc_reset); | |
1da177e4 LT |
607 | EXPORT_SYMBOL(qdisc_lock_tree); |
608 | EXPORT_SYMBOL(qdisc_unlock_tree); |