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 | ||
c716a81a JHS |
37 | #define SCHED_TX_DROP -2 |
38 | #define SCHED_TX_QUEUE -3 | |
39 | ||
1da177e4 LT |
40 | /* Main transmission queue. */ |
41 | ||
0463d4ae PM |
42 | /* Modifications to data participating in scheduling must be protected with |
43 | * dev->queue_lock spinlock. | |
44 | * | |
45 | * The idea is the following: | |
46 | * - enqueue, dequeue are serialized via top level device | |
47 | * spinlock dev->queue_lock. | |
fd44de7c PM |
48 | * - ingress filtering is serialized via top level device |
49 | * spinlock dev->ingress_lock. | |
0463d4ae | 50 | * - updates to tree and tree walking are only done under the rtnl mutex. |
1da177e4 | 51 | */ |
1da177e4 LT |
52 | |
53 | void qdisc_lock_tree(struct net_device *dev) | |
54 | { | |
1da177e4 | 55 | spin_lock_bh(&dev->queue_lock); |
fd44de7c | 56 | spin_lock(&dev->ingress_lock); |
1da177e4 LT |
57 | } |
58 | ||
59 | void qdisc_unlock_tree(struct net_device *dev) | |
60 | { | |
fd44de7c | 61 | spin_unlock(&dev->ingress_lock); |
1da177e4 | 62 | spin_unlock_bh(&dev->queue_lock); |
1da177e4 LT |
63 | } |
64 | ||
c716a81a JHS |
65 | static inline int qdisc_qlen(struct Qdisc *q) |
66 | { | |
67 | BUG_ON((int) q->q.qlen < 0); | |
68 | return q->q.qlen; | |
69 | } | |
70 | ||
71 | static inline int handle_dev_cpu_collision(struct net_device *dev) | |
72 | { | |
73 | if (unlikely(dev->xmit_lock_owner == smp_processor_id())) { | |
74 | if (net_ratelimit()) | |
75 | printk(KERN_WARNING | |
76 | "Dead loop on netdevice %s, fix it urgently!\n", | |
77 | dev->name); | |
78 | return SCHED_TX_DROP; | |
79 | } | |
80 | __get_cpu_var(netdev_rx_stat).cpu_collision++; | |
81 | return SCHED_TX_QUEUE; | |
82 | } | |
83 | ||
84 | static inline int | |
85 | do_dev_requeue(struct sk_buff *skb, struct net_device *dev, struct Qdisc *q) | |
86 | { | |
87 | ||
88 | if (unlikely(skb->next)) | |
89 | dev->gso_skb = skb; | |
90 | else | |
91 | q->ops->requeue(skb, q); | |
92 | /* XXX: Could netif_schedule fail? Or is the fact we are | |
93 | * requeueing imply the hardware path is closed | |
94 | * and even if we fail, some interupt will wake us | |
95 | */ | |
96 | netif_schedule(dev); | |
97 | return 0; | |
98 | } | |
99 | ||
100 | static inline struct sk_buff * | |
101 | try_get_tx_pkt(struct net_device *dev, struct Qdisc *q) | |
102 | { | |
103 | struct sk_buff *skb = dev->gso_skb; | |
104 | ||
105 | if (skb) | |
106 | dev->gso_skb = NULL; | |
107 | else | |
108 | skb = q->dequeue(q); | |
109 | ||
110 | return skb; | |
111 | } | |
112 | ||
113 | static inline int | |
114 | tx_islocked(struct sk_buff *skb, struct net_device *dev, struct Qdisc *q) | |
115 | { | |
116 | int ret = handle_dev_cpu_collision(dev); | |
117 | ||
118 | if (ret == SCHED_TX_DROP) { | |
119 | kfree_skb(skb); | |
120 | return qdisc_qlen(q); | |
121 | } | |
122 | ||
123 | return do_dev_requeue(skb, dev, q); | |
124 | } | |
125 | ||
126 | ||
10297b99 | 127 | /* |
c716a81a JHS |
128 | NOTE: Called under dev->queue_lock with locally disabled BH. |
129 | ||
130 | __LINK_STATE_QDISC_RUNNING guarantees only one CPU | |
131 | can enter this region at a time. | |
132 | ||
1da177e4 LT |
133 | dev->queue_lock serializes queue accesses for this device |
134 | AND dev->qdisc pointer itself. | |
135 | ||
932ff279 | 136 | netif_tx_lock serializes accesses to device driver. |
1da177e4 | 137 | |
932ff279 | 138 | dev->queue_lock and netif_tx_lock are mutually exclusive, |
1da177e4 | 139 | if one is grabbed, another must be free. |
1da177e4 | 140 | |
c716a81a | 141 | Multiple CPUs may contend for the two locks. |
1da177e4 | 142 | |
c716a81a | 143 | Note, that this procedure can be called by a watchdog timer |
1da177e4 | 144 | |
c716a81a | 145 | Returns to the caller: |
d90df3ad HX |
146 | Returns: 0 - queue is empty or throttled. |
147 | >0 - queue is not empty. | |
1da177e4 | 148 | |
1da177e4 LT |
149 | */ |
150 | ||
48d83325 | 151 | static inline int qdisc_restart(struct net_device *dev) |
1da177e4 LT |
152 | { |
153 | struct Qdisc *q = dev->qdisc; | |
c716a81a | 154 | unsigned lockless = (dev->features & NETIF_F_LLTX); |
1da177e4 | 155 | struct sk_buff *skb; |
c716a81a | 156 | int ret; |
1da177e4 | 157 | |
c716a81a JHS |
158 | skb = try_get_tx_pkt(dev, q); |
159 | if (skb == NULL) | |
160 | return 0; | |
f6a78bfc | 161 | |
c716a81a JHS |
162 | /* we have a packet to send */ |
163 | if (!lockless) { | |
164 | if (!netif_tx_trylock(dev)) | |
165 | return tx_islocked(skb, dev, q); | |
1da177e4 | 166 | } |
c716a81a JHS |
167 | /* all clear .. */ |
168 | spin_unlock(&dev->queue_lock); | |
169 | ||
170 | ret = NETDEV_TX_BUSY; | |
171 | if (!netif_queue_stopped(dev)) | |
172 | /* churn baby churn .. */ | |
173 | ret = dev_hard_start_xmit(skb, dev); | |
174 | ||
175 | if (!lockless) | |
176 | netif_tx_unlock(dev); | |
177 | ||
178 | spin_lock(&dev->queue_lock); | |
179 | ||
180 | /* we need to refresh q because it may be invalid since | |
181 | * we dropped dev->queue_lock earlier ... | |
182 | * So dont try to be clever grasshopper | |
183 | */ | |
184 | q = dev->qdisc; | |
185 | /* most likely result, packet went ok */ | |
186 | if (ret == NETDEV_TX_OK) | |
187 | return qdisc_qlen(q); | |
188 | /* only for lockless drivers .. */ | |
189 | if (ret == NETDEV_TX_LOCKED && lockless) | |
190 | return tx_islocked(skb, dev, q); | |
191 | ||
192 | if (unlikely (ret != NETDEV_TX_BUSY && net_ratelimit())) | |
193 | printk(KERN_WARNING " BUG %s code %d qlen %d\n",dev->name, ret, q->q.qlen); | |
194 | ||
195 | return do_dev_requeue(skb, dev, q); | |
1da177e4 LT |
196 | } |
197 | ||
c716a81a | 198 | |
48d83325 HX |
199 | void __qdisc_run(struct net_device *dev) |
200 | { | |
d90df3ad HX |
201 | do { |
202 | if (!qdisc_restart(dev)) | |
203 | break; | |
204 | } while (!netif_queue_stopped(dev)); | |
48d83325 HX |
205 | |
206 | clear_bit(__LINK_STATE_QDISC_RUNNING, &dev->state); | |
207 | } | |
208 | ||
1da177e4 LT |
209 | static void dev_watchdog(unsigned long arg) |
210 | { | |
211 | struct net_device *dev = (struct net_device *)arg; | |
212 | ||
932ff279 | 213 | netif_tx_lock(dev); |
1da177e4 LT |
214 | if (dev->qdisc != &noop_qdisc) { |
215 | if (netif_device_present(dev) && | |
216 | netif_running(dev) && | |
217 | netif_carrier_ok(dev)) { | |
218 | if (netif_queue_stopped(dev) && | |
338f7566 SH |
219 | time_after(jiffies, dev->trans_start + dev->watchdog_timeo)) { |
220 | ||
221 | printk(KERN_INFO "NETDEV WATCHDOG: %s: transmit timed out\n", | |
222 | dev->name); | |
1da177e4 LT |
223 | dev->tx_timeout(dev); |
224 | } | |
f5a6e01c | 225 | if (!mod_timer(&dev->watchdog_timer, round_jiffies(jiffies + dev->watchdog_timeo))) |
1da177e4 LT |
226 | dev_hold(dev); |
227 | } | |
228 | } | |
932ff279 | 229 | netif_tx_unlock(dev); |
1da177e4 LT |
230 | |
231 | dev_put(dev); | |
232 | } | |
233 | ||
234 | static void dev_watchdog_init(struct net_device *dev) | |
235 | { | |
236 | init_timer(&dev->watchdog_timer); | |
237 | dev->watchdog_timer.data = (unsigned long)dev; | |
238 | dev->watchdog_timer.function = dev_watchdog; | |
239 | } | |
240 | ||
241 | void __netdev_watchdog_up(struct net_device *dev) | |
242 | { | |
243 | if (dev->tx_timeout) { | |
244 | if (dev->watchdog_timeo <= 0) | |
245 | dev->watchdog_timeo = 5*HZ; | |
60468d5b VP |
246 | if (!mod_timer(&dev->watchdog_timer, |
247 | round_jiffies(jiffies + dev->watchdog_timeo))) | |
1da177e4 LT |
248 | dev_hold(dev); |
249 | } | |
250 | } | |
251 | ||
252 | static void dev_watchdog_up(struct net_device *dev) | |
253 | { | |
1da177e4 | 254 | __netdev_watchdog_up(dev); |
1da177e4 LT |
255 | } |
256 | ||
257 | static void dev_watchdog_down(struct net_device *dev) | |
258 | { | |
932ff279 | 259 | netif_tx_lock_bh(dev); |
1da177e4 | 260 | if (del_timer(&dev->watchdog_timer)) |
15333061 | 261 | dev_put(dev); |
932ff279 | 262 | netif_tx_unlock_bh(dev); |
1da177e4 LT |
263 | } |
264 | ||
0a242efc DV |
265 | void netif_carrier_on(struct net_device *dev) |
266 | { | |
267 | if (test_and_clear_bit(__LINK_STATE_NOCARRIER, &dev->state)) | |
268 | linkwatch_fire_event(dev); | |
269 | if (netif_running(dev)) | |
270 | __netdev_watchdog_up(dev); | |
271 | } | |
272 | ||
273 | void netif_carrier_off(struct net_device *dev) | |
274 | { | |
275 | if (!test_and_set_bit(__LINK_STATE_NOCARRIER, &dev->state)) | |
276 | linkwatch_fire_event(dev); | |
277 | } | |
278 | ||
1da177e4 LT |
279 | /* "NOOP" scheduler: the best scheduler, recommended for all interfaces |
280 | under all circumstances. It is difficult to invent anything faster or | |
281 | cheaper. | |
282 | */ | |
283 | ||
94df109a | 284 | static int noop_enqueue(struct sk_buff *skb, struct Qdisc * qdisc) |
1da177e4 LT |
285 | { |
286 | kfree_skb(skb); | |
287 | return NET_XMIT_CN; | |
288 | } | |
289 | ||
94df109a | 290 | static struct sk_buff *noop_dequeue(struct Qdisc * qdisc) |
1da177e4 LT |
291 | { |
292 | return NULL; | |
293 | } | |
294 | ||
94df109a | 295 | static int noop_requeue(struct sk_buff *skb, struct Qdisc* qdisc) |
1da177e4 LT |
296 | { |
297 | if (net_ratelimit()) | |
94df109a TG |
298 | printk(KERN_DEBUG "%s deferred output. It is buggy.\n", |
299 | skb->dev->name); | |
1da177e4 LT |
300 | kfree_skb(skb); |
301 | return NET_XMIT_CN; | |
302 | } | |
303 | ||
304 | struct Qdisc_ops noop_qdisc_ops = { | |
1da177e4 LT |
305 | .id = "noop", |
306 | .priv_size = 0, | |
307 | .enqueue = noop_enqueue, | |
308 | .dequeue = noop_dequeue, | |
309 | .requeue = noop_requeue, | |
310 | .owner = THIS_MODULE, | |
311 | }; | |
312 | ||
313 | struct Qdisc noop_qdisc = { | |
314 | .enqueue = noop_enqueue, | |
315 | .dequeue = noop_dequeue, | |
316 | .flags = TCQ_F_BUILTIN, | |
10297b99 | 317 | .ops = &noop_qdisc_ops, |
1da177e4 LT |
318 | .list = LIST_HEAD_INIT(noop_qdisc.list), |
319 | }; | |
320 | ||
321 | static struct Qdisc_ops noqueue_qdisc_ops = { | |
1da177e4 LT |
322 | .id = "noqueue", |
323 | .priv_size = 0, | |
324 | .enqueue = noop_enqueue, | |
325 | .dequeue = noop_dequeue, | |
326 | .requeue = noop_requeue, | |
327 | .owner = THIS_MODULE, | |
328 | }; | |
329 | ||
330 | static struct Qdisc noqueue_qdisc = { | |
331 | .enqueue = NULL, | |
332 | .dequeue = noop_dequeue, | |
333 | .flags = TCQ_F_BUILTIN, | |
334 | .ops = &noqueue_qdisc_ops, | |
335 | .list = LIST_HEAD_INIT(noqueue_qdisc.list), | |
336 | }; | |
337 | ||
338 | ||
339 | static const u8 prio2band[TC_PRIO_MAX+1] = | |
340 | { 1, 2, 2, 2, 1, 2, 0, 0 , 1, 1, 1, 1, 1, 1, 1, 1 }; | |
341 | ||
342 | /* 3-band FIFO queue: old style, but should be a bit faster than | |
343 | generic prio+fifo combination. | |
344 | */ | |
345 | ||
f87a9c3d TG |
346 | #define PFIFO_FAST_BANDS 3 |
347 | ||
321090e7 TG |
348 | static inline struct sk_buff_head *prio2list(struct sk_buff *skb, |
349 | struct Qdisc *qdisc) | |
1da177e4 LT |
350 | { |
351 | struct sk_buff_head *list = qdisc_priv(qdisc); | |
321090e7 TG |
352 | return list + prio2band[skb->priority & TC_PRIO_MAX]; |
353 | } | |
1da177e4 | 354 | |
f87a9c3d | 355 | static int pfifo_fast_enqueue(struct sk_buff *skb, struct Qdisc* qdisc) |
321090e7 TG |
356 | { |
357 | struct sk_buff_head *list = prio2list(skb, qdisc); | |
1da177e4 | 358 | |
821d24ae | 359 | if (skb_queue_len(list) < qdisc->dev->tx_queue_len) { |
1da177e4 | 360 | qdisc->q.qlen++; |
821d24ae | 361 | return __qdisc_enqueue_tail(skb, qdisc, list); |
1da177e4 | 362 | } |
821d24ae TG |
363 | |
364 | return qdisc_drop(skb, qdisc); | |
1da177e4 LT |
365 | } |
366 | ||
f87a9c3d | 367 | static struct sk_buff *pfifo_fast_dequeue(struct Qdisc* qdisc) |
1da177e4 LT |
368 | { |
369 | int prio; | |
370 | struct sk_buff_head *list = qdisc_priv(qdisc); | |
1da177e4 | 371 | |
452f299d TG |
372 | for (prio = 0; prio < PFIFO_FAST_BANDS; prio++) { |
373 | if (!skb_queue_empty(list + prio)) { | |
1da177e4 | 374 | qdisc->q.qlen--; |
452f299d | 375 | return __qdisc_dequeue_head(qdisc, list + prio); |
1da177e4 LT |
376 | } |
377 | } | |
f87a9c3d | 378 | |
1da177e4 LT |
379 | return NULL; |
380 | } | |
381 | ||
f87a9c3d | 382 | static int pfifo_fast_requeue(struct sk_buff *skb, struct Qdisc* qdisc) |
1da177e4 | 383 | { |
1da177e4 | 384 | qdisc->q.qlen++; |
321090e7 | 385 | return __qdisc_requeue(skb, qdisc, prio2list(skb, qdisc)); |
1da177e4 LT |
386 | } |
387 | ||
f87a9c3d | 388 | static void pfifo_fast_reset(struct Qdisc* qdisc) |
1da177e4 LT |
389 | { |
390 | int prio; | |
391 | struct sk_buff_head *list = qdisc_priv(qdisc); | |
392 | ||
f87a9c3d | 393 | for (prio = 0; prio < PFIFO_FAST_BANDS; prio++) |
821d24ae TG |
394 | __qdisc_reset_queue(qdisc, list + prio); |
395 | ||
396 | qdisc->qstats.backlog = 0; | |
1da177e4 LT |
397 | qdisc->q.qlen = 0; |
398 | } | |
399 | ||
400 | static int pfifo_fast_dump(struct Qdisc *qdisc, struct sk_buff *skb) | |
401 | { | |
f87a9c3d | 402 | struct tc_prio_qopt opt = { .bands = PFIFO_FAST_BANDS }; |
1da177e4 | 403 | |
1da177e4 LT |
404 | memcpy(&opt.priomap, prio2band, TC_PRIO_MAX+1); |
405 | RTA_PUT(skb, TCA_OPTIONS, sizeof(opt), &opt); | |
406 | return skb->len; | |
407 | ||
408 | rtattr_failure: | |
1da177e4 LT |
409 | return -1; |
410 | } | |
411 | ||
412 | static int pfifo_fast_init(struct Qdisc *qdisc, struct rtattr *opt) | |
413 | { | |
f87a9c3d | 414 | int prio; |
1da177e4 LT |
415 | struct sk_buff_head *list = qdisc_priv(qdisc); |
416 | ||
f87a9c3d TG |
417 | for (prio = 0; prio < PFIFO_FAST_BANDS; prio++) |
418 | skb_queue_head_init(list + prio); | |
1da177e4 LT |
419 | |
420 | return 0; | |
421 | } | |
422 | ||
423 | static struct Qdisc_ops pfifo_fast_ops = { | |
1da177e4 | 424 | .id = "pfifo_fast", |
f87a9c3d | 425 | .priv_size = PFIFO_FAST_BANDS * sizeof(struct sk_buff_head), |
1da177e4 LT |
426 | .enqueue = pfifo_fast_enqueue, |
427 | .dequeue = pfifo_fast_dequeue, | |
428 | .requeue = pfifo_fast_requeue, | |
429 | .init = pfifo_fast_init, | |
430 | .reset = pfifo_fast_reset, | |
431 | .dump = pfifo_fast_dump, | |
432 | .owner = THIS_MODULE, | |
433 | }; | |
434 | ||
3d54b82f | 435 | struct Qdisc *qdisc_alloc(struct net_device *dev, struct Qdisc_ops *ops) |
1da177e4 LT |
436 | { |
437 | void *p; | |
438 | struct Qdisc *sch; | |
3d54b82f TG |
439 | unsigned int size; |
440 | int err = -ENOBUFS; | |
1da177e4 LT |
441 | |
442 | /* ensure that the Qdisc and the private data are 32-byte aligned */ | |
3d54b82f TG |
443 | size = QDISC_ALIGN(sizeof(*sch)); |
444 | size += ops->priv_size + (QDISC_ALIGNTO - 1); | |
1da177e4 | 445 | |
0da974f4 | 446 | p = kzalloc(size, GFP_KERNEL); |
1da177e4 | 447 | if (!p) |
3d54b82f | 448 | goto errout; |
3d54b82f TG |
449 | sch = (struct Qdisc *) QDISC_ALIGN((unsigned long) p); |
450 | sch->padded = (char *) sch - (char *) p; | |
1da177e4 LT |
451 | |
452 | INIT_LIST_HEAD(&sch->list); | |
453 | skb_queue_head_init(&sch->q); | |
454 | sch->ops = ops; | |
455 | sch->enqueue = ops->enqueue; | |
456 | sch->dequeue = ops->dequeue; | |
457 | sch->dev = dev; | |
458 | dev_hold(dev); | |
1da177e4 | 459 | atomic_set(&sch->refcnt, 1); |
3d54b82f TG |
460 | |
461 | return sch; | |
462 | errout: | |
463 | return ERR_PTR(-err); | |
464 | } | |
465 | ||
9f9afec4 PM |
466 | struct Qdisc * qdisc_create_dflt(struct net_device *dev, struct Qdisc_ops *ops, |
467 | unsigned int parentid) | |
3d54b82f TG |
468 | { |
469 | struct Qdisc *sch; | |
10297b99 | 470 | |
3d54b82f TG |
471 | sch = qdisc_alloc(dev, ops); |
472 | if (IS_ERR(sch)) | |
473 | goto errout; | |
fd44de7c | 474 | sch->stats_lock = &dev->queue_lock; |
9f9afec4 | 475 | sch->parent = parentid; |
3d54b82f | 476 | |
1da177e4 LT |
477 | if (!ops->init || ops->init(sch, NULL) == 0) |
478 | return sch; | |
479 | ||
0fbbeb1b | 480 | qdisc_destroy(sch); |
3d54b82f | 481 | errout: |
1da177e4 LT |
482 | return NULL; |
483 | } | |
484 | ||
485 | /* Under dev->queue_lock and BH! */ | |
486 | ||
487 | void qdisc_reset(struct Qdisc *qdisc) | |
488 | { | |
489 | struct Qdisc_ops *ops = qdisc->ops; | |
490 | ||
491 | if (ops->reset) | |
492 | ops->reset(qdisc); | |
493 | } | |
494 | ||
10297b99 | 495 | /* this is the rcu callback function to clean up a qdisc when there |
1da177e4 LT |
496 | * are no further references to it */ |
497 | ||
498 | static void __qdisc_destroy(struct rcu_head *head) | |
499 | { | |
500 | struct Qdisc *qdisc = container_of(head, struct Qdisc, q_rcu); | |
1da177e4 LT |
501 | kfree((char *) qdisc - qdisc->padded); |
502 | } | |
503 | ||
504 | /* Under dev->queue_lock and BH! */ | |
505 | ||
506 | void qdisc_destroy(struct Qdisc *qdisc) | |
507 | { | |
85670cc1 | 508 | struct Qdisc_ops *ops = qdisc->ops; |
1da177e4 LT |
509 | |
510 | if (qdisc->flags & TCQ_F_BUILTIN || | |
85670cc1 | 511 | !atomic_dec_and_test(&qdisc->refcnt)) |
1da177e4 LT |
512 | return; |
513 | ||
85670cc1 PM |
514 | list_del(&qdisc->list); |
515 | #ifdef CONFIG_NET_ESTIMATOR | |
516 | gen_kill_estimator(&qdisc->bstats, &qdisc->rate_est); | |
517 | #endif | |
518 | if (ops->reset) | |
519 | ops->reset(qdisc); | |
520 | if (ops->destroy) | |
521 | ops->destroy(qdisc); | |
1da177e4 | 522 | |
85670cc1 PM |
523 | module_put(ops->owner); |
524 | dev_put(qdisc->dev); | |
1da177e4 LT |
525 | call_rcu(&qdisc->q_rcu, __qdisc_destroy); |
526 | } | |
527 | ||
528 | void dev_activate(struct net_device *dev) | |
529 | { | |
530 | /* No queueing discipline is attached to device; | |
531 | create default one i.e. pfifo_fast for devices, | |
532 | which need queueing and noqueue_qdisc for | |
533 | virtual interfaces | |
534 | */ | |
535 | ||
536 | if (dev->qdisc_sleeping == &noop_qdisc) { | |
537 | struct Qdisc *qdisc; | |
538 | if (dev->tx_queue_len) { | |
9f9afec4 PM |
539 | qdisc = qdisc_create_dflt(dev, &pfifo_fast_ops, |
540 | TC_H_ROOT); | |
1da177e4 LT |
541 | if (qdisc == NULL) { |
542 | printk(KERN_INFO "%s: activation failed\n", dev->name); | |
543 | return; | |
544 | } | |
1da177e4 | 545 | list_add_tail(&qdisc->list, &dev->qdisc_list); |
1da177e4 LT |
546 | } else { |
547 | qdisc = &noqueue_qdisc; | |
548 | } | |
1da177e4 | 549 | dev->qdisc_sleeping = qdisc; |
1da177e4 LT |
550 | } |
551 | ||
cacaddf5 TC |
552 | if (!netif_carrier_ok(dev)) |
553 | /* Delay activation until next carrier-on event */ | |
554 | return; | |
555 | ||
1da177e4 LT |
556 | spin_lock_bh(&dev->queue_lock); |
557 | rcu_assign_pointer(dev->qdisc, dev->qdisc_sleeping); | |
558 | if (dev->qdisc != &noqueue_qdisc) { | |
559 | dev->trans_start = jiffies; | |
560 | dev_watchdog_up(dev); | |
561 | } | |
562 | spin_unlock_bh(&dev->queue_lock); | |
563 | } | |
564 | ||
565 | void dev_deactivate(struct net_device *dev) | |
566 | { | |
567 | struct Qdisc *qdisc; | |
41a23b07 | 568 | struct sk_buff *skb; |
1da177e4 LT |
569 | |
570 | spin_lock_bh(&dev->queue_lock); | |
571 | qdisc = dev->qdisc; | |
572 | dev->qdisc = &noop_qdisc; | |
573 | ||
574 | qdisc_reset(qdisc); | |
575 | ||
41a23b07 HX |
576 | skb = dev->gso_skb; |
577 | dev->gso_skb = NULL; | |
1da177e4 LT |
578 | spin_unlock_bh(&dev->queue_lock); |
579 | ||
41a23b07 HX |
580 | kfree_skb(skb); |
581 | ||
1da177e4 LT |
582 | dev_watchdog_down(dev); |
583 | ||
d4828d85 HX |
584 | /* Wait for outstanding dev_queue_xmit calls. */ |
585 | synchronize_rcu(); | |
1da177e4 | 586 | |
d4828d85 HX |
587 | /* Wait for outstanding qdisc_run calls. */ |
588 | while (test_bit(__LINK_STATE_QDISC_RUNNING, &dev->state)) | |
589 | yield(); | |
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) | |
10297b99 | 613 | if ((qdisc = dev->qdisc_ingress) != NULL) { |
1da177e4 LT |
614 | dev->qdisc_ingress = NULL; |
615 | qdisc_destroy(qdisc); | |
10297b99 | 616 | } |
1da177e4 LT |
617 | #endif |
618 | BUG_TRAP(!timer_pending(&dev->watchdog_timer)); | |
619 | qdisc_unlock_tree(dev); | |
620 | } | |
621 | ||
0a242efc DV |
622 | EXPORT_SYMBOL(netif_carrier_on); |
623 | EXPORT_SYMBOL(netif_carrier_off); | |
1da177e4 | 624 | EXPORT_SYMBOL(noop_qdisc); |
1da177e4 LT |
625 | EXPORT_SYMBOL(qdisc_create_dflt); |
626 | EXPORT_SYMBOL(qdisc_destroy); | |
627 | EXPORT_SYMBOL(qdisc_reset); | |
1da177e4 LT |
628 | EXPORT_SYMBOL(qdisc_lock_tree); |
629 | EXPORT_SYMBOL(qdisc_unlock_tree); |