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 | ||
1da177e4 | 14 | #include <linux/bitops.h> |
1da177e4 LT |
15 | #include <linux/module.h> |
16 | #include <linux/types.h> | |
17 | #include <linux/kernel.h> | |
18 | #include <linux/sched.h> | |
19 | #include <linux/string.h> | |
1da177e4 | 20 | #include <linux/errno.h> |
1da177e4 LT |
21 | #include <linux/netdevice.h> |
22 | #include <linux/skbuff.h> | |
23 | #include <linux/rtnetlink.h> | |
24 | #include <linux/init.h> | |
25 | #include <linux/rcupdate.h> | |
26 | #include <linux/list.h> | |
1da177e4 LT |
27 | #include <net/pkt_sched.h> |
28 | ||
29 | /* Main transmission queue. */ | |
30 | ||
0463d4ae | 31 | /* Modifications to data participating in scheduling must be protected with |
5fb66229 | 32 | * qdisc_lock(qdisc) spinlock. |
0463d4ae PM |
33 | * |
34 | * The idea is the following: | |
c7e4f3bb DM |
35 | * - enqueue, dequeue are serialized via qdisc root lock |
36 | * - ingress filtering is also serialized via qdisc root lock | |
0463d4ae | 37 | * - updates to tree and tree walking are only done under the rtnl mutex. |
1da177e4 | 38 | */ |
1da177e4 | 39 | |
37437bb2 | 40 | static inline int dev_requeue_skb(struct sk_buff *skb, struct Qdisc *q) |
c716a81a | 41 | { |
6252352d | 42 | q->gso_skb = skb; |
53e91503 | 43 | q->qstats.requeues++; |
bbd8a0d3 | 44 | q->q.qlen++; /* it's still part of the queue */ |
37437bb2 | 45 | __netif_schedule(q); |
6252352d | 46 | |
c716a81a JHS |
47 | return 0; |
48 | } | |
49 | ||
d3b753db | 50 | static inline struct sk_buff *dequeue_skb(struct Qdisc *q) |
c716a81a | 51 | { |
554794de JP |
52 | struct sk_buff *skb = q->gso_skb; |
53 | ||
ebf05982 JP |
54 | if (unlikely(skb)) { |
55 | struct net_device *dev = qdisc_dev(q); | |
56 | struct netdev_queue *txq; | |
57 | ||
58 | /* check the reason of requeuing without tx lock first */ | |
59 | txq = netdev_get_tx_queue(dev, skb_get_queue_mapping(skb)); | |
bbd8a0d3 KK |
60 | if (!netif_tx_queue_stopped(txq) && |
61 | !netif_tx_queue_frozen(txq)) { | |
6252352d | 62 | q->gso_skb = NULL; |
bbd8a0d3 KK |
63 | q->q.qlen--; |
64 | } else | |
ebf05982 JP |
65 | skb = NULL; |
66 | } else { | |
c716a81a | 67 | skb = q->dequeue(q); |
ebf05982 | 68 | } |
c716a81a JHS |
69 | |
70 | return skb; | |
71 | } | |
72 | ||
6c1361a6 | 73 | static inline int handle_dev_cpu_collision(struct sk_buff *skb, |
970565bb | 74 | struct netdev_queue *dev_queue, |
6c1361a6 | 75 | struct Qdisc *q) |
c716a81a | 76 | { |
6c1361a6 | 77 | int ret; |
c716a81a | 78 | |
c773e847 | 79 | if (unlikely(dev_queue->xmit_lock_owner == smp_processor_id())) { |
6c1361a6 KK |
80 | /* |
81 | * Same CPU holding the lock. It may be a transient | |
82 | * configuration error, when hard_start_xmit() recurses. We | |
83 | * detect it by checking xmit owner and drop the packet when | |
84 | * deadloop is detected. Return OK to try the next skb. | |
85 | */ | |
c716a81a | 86 | kfree_skb(skb); |
6c1361a6 KK |
87 | if (net_ratelimit()) |
88 | printk(KERN_WARNING "Dead loop on netdevice %s, " | |
c773e847 | 89 | "fix it urgently!\n", dev_queue->dev->name); |
6c1361a6 KK |
90 | ret = qdisc_qlen(q); |
91 | } else { | |
92 | /* | |
93 | * Another cpu is holding lock, requeue & delay xmits for | |
94 | * some time. | |
95 | */ | |
96 | __get_cpu_var(netdev_rx_stat).cpu_collision++; | |
37437bb2 | 97 | ret = dev_requeue_skb(skb, q); |
c716a81a JHS |
98 | } |
99 | ||
6c1361a6 | 100 | return ret; |
c716a81a JHS |
101 | } |
102 | ||
10297b99 | 103 | /* |
bbd8a0d3 KK |
104 | * Transmit one skb, and handle the return status as required. Holding the |
105 | * __QDISC_STATE_RUNNING bit guarantees that only one CPU can execute this | |
106 | * function. | |
6c1361a6 KK |
107 | * |
108 | * Returns to the caller: | |
109 | * 0 - queue is empty or throttled. | |
110 | * >0 - queue is not empty. | |
6c1361a6 | 111 | */ |
bbd8a0d3 KK |
112 | int sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q, |
113 | struct net_device *dev, struct netdev_queue *txq, | |
114 | spinlock_t *root_lock) | |
1da177e4 | 115 | { |
5f1a485d | 116 | int ret = NETDEV_TX_BUSY; |
7698b4fc DM |
117 | |
118 | /* And release qdisc */ | |
119 | spin_unlock(root_lock); | |
c716a81a | 120 | |
c773e847 | 121 | HARD_TX_LOCK(dev, txq, smp_processor_id()); |
9a1654ba | 122 | if (!netif_tx_queue_stopped(txq) && !netif_tx_queue_frozen(txq)) |
fd2ea0a7 | 123 | ret = dev_hard_start_xmit(skb, dev, txq); |
572a9d7b | 124 | |
c773e847 | 125 | HARD_TX_UNLOCK(dev, txq); |
c716a81a | 126 | |
7698b4fc | 127 | spin_lock(root_lock); |
c716a81a | 128 | |
9a1654ba JP |
129 | if (dev_xmit_complete(ret)) { |
130 | /* Driver sent out skb successfully or skb was consumed */ | |
6c1361a6 | 131 | ret = qdisc_qlen(q); |
9a1654ba | 132 | } else if (ret == NETDEV_TX_LOCKED) { |
6c1361a6 | 133 | /* Driver try lock failed */ |
eb6aafe3 | 134 | ret = handle_dev_cpu_collision(skb, txq, q); |
9a1654ba | 135 | } else { |
6c1361a6 KK |
136 | /* Driver returned NETDEV_TX_BUSY - requeue skb */ |
137 | if (unlikely (ret != NETDEV_TX_BUSY && net_ratelimit())) | |
138 | printk(KERN_WARNING "BUG %s code %d qlen %d\n", | |
139 | dev->name, ret, q->q.qlen); | |
140 | ||
37437bb2 | 141 | ret = dev_requeue_skb(skb, q); |
6c1361a6 | 142 | } |
c716a81a | 143 | |
c3f26a26 DM |
144 | if (ret && (netif_tx_queue_stopped(txq) || |
145 | netif_tx_queue_frozen(txq))) | |
37437bb2 DM |
146 | ret = 0; |
147 | ||
6c1361a6 | 148 | return ret; |
1da177e4 LT |
149 | } |
150 | ||
bbd8a0d3 KK |
151 | /* |
152 | * NOTE: Called under qdisc_lock(q) with locally disabled BH. | |
153 | * | |
154 | * __QDISC_STATE_RUNNING guarantees only one CPU can process | |
155 | * this qdisc at a time. qdisc_lock(q) serializes queue accesses for | |
156 | * this queue. | |
157 | * | |
158 | * netif_tx_lock serializes accesses to device driver. | |
159 | * | |
160 | * qdisc_lock(q) and netif_tx_lock are mutually exclusive, | |
161 | * if one is grabbed, another must be free. | |
162 | * | |
163 | * Note, that this procedure can be called by a watchdog timer | |
164 | * | |
165 | * Returns to the caller: | |
166 | * 0 - queue is empty or throttled. | |
167 | * >0 - queue is not empty. | |
168 | * | |
169 | */ | |
170 | static inline int qdisc_restart(struct Qdisc *q) | |
171 | { | |
172 | struct netdev_queue *txq; | |
173 | struct net_device *dev; | |
174 | spinlock_t *root_lock; | |
175 | struct sk_buff *skb; | |
176 | ||
177 | /* Dequeue packet */ | |
178 | skb = dequeue_skb(q); | |
179 | if (unlikely(!skb)) | |
180 | return 0; | |
181 | ||
182 | root_lock = qdisc_lock(q); | |
183 | dev = qdisc_dev(q); | |
184 | txq = netdev_get_tx_queue(dev, skb_get_queue_mapping(skb)); | |
185 | ||
186 | return sch_direct_xmit(skb, q, dev, txq, root_lock); | |
187 | } | |
188 | ||
37437bb2 | 189 | void __qdisc_run(struct Qdisc *q) |
48d83325 | 190 | { |
2ba2506c | 191 | unsigned long start_time = jiffies; |
2ba2506c | 192 | |
37437bb2 | 193 | while (qdisc_restart(q)) { |
2ba2506c HX |
194 | /* |
195 | * Postpone processing if | |
196 | * 1. another process needs the CPU; | |
197 | * 2. we've been doing it for too long. | |
198 | */ | |
199 | if (need_resched() || jiffies != start_time) { | |
37437bb2 | 200 | __netif_schedule(q); |
d90df3ad | 201 | break; |
2ba2506c HX |
202 | } |
203 | } | |
48d83325 | 204 | |
e2627c8c | 205 | clear_bit(__QDISC_STATE_RUNNING, &q->state); |
48d83325 HX |
206 | } |
207 | ||
9d21493b ED |
208 | unsigned long dev_trans_start(struct net_device *dev) |
209 | { | |
210 | unsigned long val, res = dev->trans_start; | |
211 | unsigned int i; | |
212 | ||
213 | for (i = 0; i < dev->num_tx_queues; i++) { | |
214 | val = netdev_get_tx_queue(dev, i)->trans_start; | |
215 | if (val && time_after(val, res)) | |
216 | res = val; | |
217 | } | |
218 | dev->trans_start = res; | |
219 | return res; | |
220 | } | |
221 | EXPORT_SYMBOL(dev_trans_start); | |
222 | ||
1da177e4 LT |
223 | static void dev_watchdog(unsigned long arg) |
224 | { | |
225 | struct net_device *dev = (struct net_device *)arg; | |
226 | ||
932ff279 | 227 | netif_tx_lock(dev); |
e8a0464c | 228 | if (!qdisc_tx_is_noop(dev)) { |
1da177e4 LT |
229 | if (netif_device_present(dev) && |
230 | netif_running(dev) && | |
231 | netif_carrier_ok(dev)) { | |
9d21493b | 232 | int some_queue_timedout = 0; |
e8a0464c | 233 | unsigned int i; |
9d21493b | 234 | unsigned long trans_start; |
e8a0464c DM |
235 | |
236 | for (i = 0; i < dev->num_tx_queues; i++) { | |
237 | struct netdev_queue *txq; | |
238 | ||
239 | txq = netdev_get_tx_queue(dev, i); | |
9d21493b ED |
240 | /* |
241 | * old device drivers set dev->trans_start | |
242 | */ | |
243 | trans_start = txq->trans_start ? : dev->trans_start; | |
244 | if (netif_tx_queue_stopped(txq) && | |
245 | time_after(jiffies, (trans_start + | |
246 | dev->watchdog_timeo))) { | |
247 | some_queue_timedout = 1; | |
e8a0464c DM |
248 | break; |
249 | } | |
250 | } | |
338f7566 | 251 | |
9d21493b | 252 | if (some_queue_timedout) { |
6579e57b | 253 | char drivername[64]; |
9d21493b ED |
254 | WARN_ONCE(1, KERN_INFO "NETDEV WATCHDOG: %s (%s): transmit queue %u timed out\n", |
255 | dev->name, netdev_drivername(dev, drivername, 64), i); | |
d314774c | 256 | dev->netdev_ops->ndo_tx_timeout(dev); |
1da177e4 | 257 | } |
e8a0464c DM |
258 | if (!mod_timer(&dev->watchdog_timer, |
259 | round_jiffies(jiffies + | |
260 | dev->watchdog_timeo))) | |
1da177e4 LT |
261 | dev_hold(dev); |
262 | } | |
263 | } | |
932ff279 | 264 | netif_tx_unlock(dev); |
1da177e4 LT |
265 | |
266 | dev_put(dev); | |
267 | } | |
268 | ||
1da177e4 LT |
269 | void __netdev_watchdog_up(struct net_device *dev) |
270 | { | |
d314774c | 271 | if (dev->netdev_ops->ndo_tx_timeout) { |
1da177e4 LT |
272 | if (dev->watchdog_timeo <= 0) |
273 | dev->watchdog_timeo = 5*HZ; | |
60468d5b VP |
274 | if (!mod_timer(&dev->watchdog_timer, |
275 | round_jiffies(jiffies + dev->watchdog_timeo))) | |
1da177e4 LT |
276 | dev_hold(dev); |
277 | } | |
278 | } | |
279 | ||
280 | static void dev_watchdog_up(struct net_device *dev) | |
281 | { | |
1da177e4 | 282 | __netdev_watchdog_up(dev); |
1da177e4 LT |
283 | } |
284 | ||
285 | static void dev_watchdog_down(struct net_device *dev) | |
286 | { | |
932ff279 | 287 | netif_tx_lock_bh(dev); |
1da177e4 | 288 | if (del_timer(&dev->watchdog_timer)) |
15333061 | 289 | dev_put(dev); |
932ff279 | 290 | netif_tx_unlock_bh(dev); |
1da177e4 LT |
291 | } |
292 | ||
bea3348e SH |
293 | /** |
294 | * netif_carrier_on - set carrier | |
295 | * @dev: network device | |
296 | * | |
297 | * Device has detected that carrier. | |
298 | */ | |
0a242efc DV |
299 | void netif_carrier_on(struct net_device *dev) |
300 | { | |
bfaae0f0 | 301 | if (test_and_clear_bit(__LINK_STATE_NOCARRIER, &dev->state)) { |
b4730016 DM |
302 | if (dev->reg_state == NETREG_UNINITIALIZED) |
303 | return; | |
0a242efc | 304 | linkwatch_fire_event(dev); |
bfaae0f0 JG |
305 | if (netif_running(dev)) |
306 | __netdev_watchdog_up(dev); | |
307 | } | |
0a242efc | 308 | } |
62e3ba1b | 309 | EXPORT_SYMBOL(netif_carrier_on); |
0a242efc | 310 | |
bea3348e SH |
311 | /** |
312 | * netif_carrier_off - clear carrier | |
313 | * @dev: network device | |
314 | * | |
315 | * Device has detected loss of carrier. | |
316 | */ | |
0a242efc DV |
317 | void netif_carrier_off(struct net_device *dev) |
318 | { | |
b4730016 DM |
319 | if (!test_and_set_bit(__LINK_STATE_NOCARRIER, &dev->state)) { |
320 | if (dev->reg_state == NETREG_UNINITIALIZED) | |
321 | return; | |
0a242efc | 322 | linkwatch_fire_event(dev); |
b4730016 | 323 | } |
0a242efc | 324 | } |
62e3ba1b | 325 | EXPORT_SYMBOL(netif_carrier_off); |
0a242efc | 326 | |
1da177e4 LT |
327 | /* "NOOP" scheduler: the best scheduler, recommended for all interfaces |
328 | under all circumstances. It is difficult to invent anything faster or | |
329 | cheaper. | |
330 | */ | |
331 | ||
94df109a | 332 | static int noop_enqueue(struct sk_buff *skb, struct Qdisc * qdisc) |
1da177e4 LT |
333 | { |
334 | kfree_skb(skb); | |
335 | return NET_XMIT_CN; | |
336 | } | |
337 | ||
94df109a | 338 | static struct sk_buff *noop_dequeue(struct Qdisc * qdisc) |
1da177e4 LT |
339 | { |
340 | return NULL; | |
341 | } | |
342 | ||
20fea08b | 343 | struct Qdisc_ops noop_qdisc_ops __read_mostly = { |
1da177e4 LT |
344 | .id = "noop", |
345 | .priv_size = 0, | |
346 | .enqueue = noop_enqueue, | |
347 | .dequeue = noop_dequeue, | |
99c0db26 | 348 | .peek = noop_dequeue, |
1da177e4 LT |
349 | .owner = THIS_MODULE, |
350 | }; | |
351 | ||
7698b4fc | 352 | static struct netdev_queue noop_netdev_queue = { |
7698b4fc | 353 | .qdisc = &noop_qdisc, |
9f3ffae0 | 354 | .qdisc_sleeping = &noop_qdisc, |
7698b4fc DM |
355 | }; |
356 | ||
1da177e4 LT |
357 | struct Qdisc noop_qdisc = { |
358 | .enqueue = noop_enqueue, | |
359 | .dequeue = noop_dequeue, | |
360 | .flags = TCQ_F_BUILTIN, | |
10297b99 | 361 | .ops = &noop_qdisc_ops, |
1da177e4 | 362 | .list = LIST_HEAD_INIT(noop_qdisc.list), |
83874000 | 363 | .q.lock = __SPIN_LOCK_UNLOCKED(noop_qdisc.q.lock), |
7698b4fc | 364 | .dev_queue = &noop_netdev_queue, |
1da177e4 | 365 | }; |
62e3ba1b | 366 | EXPORT_SYMBOL(noop_qdisc); |
1da177e4 | 367 | |
20fea08b | 368 | static struct Qdisc_ops noqueue_qdisc_ops __read_mostly = { |
1da177e4 LT |
369 | .id = "noqueue", |
370 | .priv_size = 0, | |
371 | .enqueue = noop_enqueue, | |
372 | .dequeue = noop_dequeue, | |
99c0db26 | 373 | .peek = noop_dequeue, |
1da177e4 LT |
374 | .owner = THIS_MODULE, |
375 | }; | |
376 | ||
30ee42be DM |
377 | static struct Qdisc noqueue_qdisc; |
378 | static struct netdev_queue noqueue_netdev_queue = { | |
379 | .qdisc = &noqueue_qdisc, | |
9f3ffae0 | 380 | .qdisc_sleeping = &noqueue_qdisc, |
30ee42be DM |
381 | }; |
382 | ||
1da177e4 LT |
383 | static struct Qdisc noqueue_qdisc = { |
384 | .enqueue = NULL, | |
385 | .dequeue = noop_dequeue, | |
386 | .flags = TCQ_F_BUILTIN, | |
387 | .ops = &noqueue_qdisc_ops, | |
388 | .list = LIST_HEAD_INIT(noqueue_qdisc.list), | |
30ee42be DM |
389 | .q.lock = __SPIN_LOCK_UNLOCKED(noqueue_qdisc.q.lock), |
390 | .dev_queue = &noqueue_netdev_queue, | |
1da177e4 LT |
391 | }; |
392 | ||
393 | ||
d3678b46 DM |
394 | static const u8 prio2band[TC_PRIO_MAX+1] = |
395 | { 1, 2, 2, 2, 1, 2, 0, 0 , 1, 1, 1, 1, 1, 1, 1, 1 }; | |
396 | ||
397 | /* 3-band FIFO queue: old style, but should be a bit faster than | |
398 | generic prio+fifo combination. | |
399 | */ | |
400 | ||
401 | #define PFIFO_FAST_BANDS 3 | |
402 | ||
fd3ae5e8 KK |
403 | /* |
404 | * Private data for a pfifo_fast scheduler containing: | |
405 | * - queues for the three band | |
406 | * - bitmap indicating which of the bands contain skbs | |
407 | */ | |
408 | struct pfifo_fast_priv { | |
409 | u32 bitmap; | |
410 | struct sk_buff_head q[PFIFO_FAST_BANDS]; | |
411 | }; | |
412 | ||
413 | /* | |
414 | * Convert a bitmap to the first band number where an skb is queued, where: | |
415 | * bitmap=0 means there are no skbs on any band. | |
416 | * bitmap=1 means there is an skb on band 0. | |
417 | * bitmap=7 means there are skbs on all 3 bands, etc. | |
418 | */ | |
419 | static const int bitmap2band[] = {-1, 0, 1, 0, 2, 0, 1, 0}; | |
420 | ||
421 | static inline struct sk_buff_head *band2list(struct pfifo_fast_priv *priv, | |
422 | int band) | |
d3678b46 | 423 | { |
fd3ae5e8 | 424 | return priv->q + band; |
d3678b46 DM |
425 | } |
426 | ||
427 | static int pfifo_fast_enqueue(struct sk_buff *skb, struct Qdisc* qdisc) | |
321090e7 | 428 | { |
a453e068 KK |
429 | if (skb_queue_len(&qdisc->q) < qdisc_dev(qdisc)->tx_queue_len) { |
430 | int band = prio2band[skb->priority & TC_PRIO_MAX]; | |
431 | struct pfifo_fast_priv *priv = qdisc_priv(qdisc); | |
432 | struct sk_buff_head *list = band2list(priv, band); | |
1da177e4 | 433 | |
fd3ae5e8 | 434 | priv->bitmap |= (1 << band); |
d3678b46 | 435 | qdisc->q.qlen++; |
821d24ae | 436 | return __qdisc_enqueue_tail(skb, qdisc, list); |
d3678b46 | 437 | } |
821d24ae TG |
438 | |
439 | return qdisc_drop(skb, qdisc); | |
1da177e4 LT |
440 | } |
441 | ||
d3678b46 | 442 | static struct sk_buff *pfifo_fast_dequeue(struct Qdisc* qdisc) |
1da177e4 | 443 | { |
fd3ae5e8 KK |
444 | struct pfifo_fast_priv *priv = qdisc_priv(qdisc); |
445 | int band = bitmap2band[priv->bitmap]; | |
1da177e4 | 446 | |
fd3ae5e8 KK |
447 | if (likely(band >= 0)) { |
448 | struct sk_buff_head *list = band2list(priv, band); | |
449 | struct sk_buff *skb = __qdisc_dequeue_head(qdisc, list); | |
450 | ||
451 | qdisc->q.qlen--; | |
452 | if (skb_queue_empty(list)) | |
453 | priv->bitmap &= ~(1 << band); | |
454 | ||
455 | return skb; | |
d3678b46 | 456 | } |
f87a9c3d | 457 | |
1da177e4 LT |
458 | return NULL; |
459 | } | |
460 | ||
99c0db26 JP |
461 | static struct sk_buff *pfifo_fast_peek(struct Qdisc* qdisc) |
462 | { | |
fd3ae5e8 KK |
463 | struct pfifo_fast_priv *priv = qdisc_priv(qdisc); |
464 | int band = bitmap2band[priv->bitmap]; | |
465 | ||
466 | if (band >= 0) { | |
467 | struct sk_buff_head *list = band2list(priv, band); | |
99c0db26 | 468 | |
fd3ae5e8 | 469 | return skb_peek(list); |
99c0db26 JP |
470 | } |
471 | ||
472 | return NULL; | |
473 | } | |
474 | ||
d3678b46 | 475 | static void pfifo_fast_reset(struct Qdisc* qdisc) |
1da177e4 | 476 | { |
d3678b46 | 477 | int prio; |
fd3ae5e8 | 478 | struct pfifo_fast_priv *priv = qdisc_priv(qdisc); |
d3678b46 DM |
479 | |
480 | for (prio = 0; prio < PFIFO_FAST_BANDS; prio++) | |
fd3ae5e8 | 481 | __qdisc_reset_queue(qdisc, band2list(priv, prio)); |
d3678b46 | 482 | |
fd3ae5e8 | 483 | priv->bitmap = 0; |
821d24ae | 484 | qdisc->qstats.backlog = 0; |
d3678b46 | 485 | qdisc->q.qlen = 0; |
1da177e4 LT |
486 | } |
487 | ||
d3678b46 DM |
488 | static int pfifo_fast_dump(struct Qdisc *qdisc, struct sk_buff *skb) |
489 | { | |
490 | struct tc_prio_qopt opt = { .bands = PFIFO_FAST_BANDS }; | |
491 | ||
492 | memcpy(&opt.priomap, prio2band, TC_PRIO_MAX+1); | |
493 | NLA_PUT(skb, TCA_OPTIONS, sizeof(opt), &opt); | |
494 | return skb->len; | |
495 | ||
496 | nla_put_failure: | |
497 | return -1; | |
498 | } | |
499 | ||
500 | static int pfifo_fast_init(struct Qdisc *qdisc, struct nlattr *opt) | |
501 | { | |
502 | int prio; | |
fd3ae5e8 | 503 | struct pfifo_fast_priv *priv = qdisc_priv(qdisc); |
d3678b46 DM |
504 | |
505 | for (prio = 0; prio < PFIFO_FAST_BANDS; prio++) | |
fd3ae5e8 | 506 | skb_queue_head_init(band2list(priv, prio)); |
d3678b46 DM |
507 | |
508 | return 0; | |
509 | } | |
510 | ||
6ec1c69a | 511 | struct Qdisc_ops pfifo_fast_ops __read_mostly = { |
d3678b46 | 512 | .id = "pfifo_fast", |
fd3ae5e8 | 513 | .priv_size = sizeof(struct pfifo_fast_priv), |
d3678b46 DM |
514 | .enqueue = pfifo_fast_enqueue, |
515 | .dequeue = pfifo_fast_dequeue, | |
99c0db26 | 516 | .peek = pfifo_fast_peek, |
d3678b46 DM |
517 | .init = pfifo_fast_init, |
518 | .reset = pfifo_fast_reset, | |
519 | .dump = pfifo_fast_dump, | |
1da177e4 LT |
520 | .owner = THIS_MODULE, |
521 | }; | |
522 | ||
5ce2d488 | 523 | struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue, |
bb949fbd | 524 | struct Qdisc_ops *ops) |
1da177e4 LT |
525 | { |
526 | void *p; | |
527 | struct Qdisc *sch; | |
3d54b82f TG |
528 | unsigned int size; |
529 | int err = -ENOBUFS; | |
1da177e4 LT |
530 | |
531 | /* ensure that the Qdisc and the private data are 32-byte aligned */ | |
3d54b82f TG |
532 | size = QDISC_ALIGN(sizeof(*sch)); |
533 | size += ops->priv_size + (QDISC_ALIGNTO - 1); | |
1da177e4 | 534 | |
0da974f4 | 535 | p = kzalloc(size, GFP_KERNEL); |
1da177e4 | 536 | if (!p) |
3d54b82f | 537 | goto errout; |
3d54b82f TG |
538 | sch = (struct Qdisc *) QDISC_ALIGN((unsigned long) p); |
539 | sch->padded = (char *) sch - (char *) p; | |
1da177e4 LT |
540 | |
541 | INIT_LIST_HEAD(&sch->list); | |
542 | skb_queue_head_init(&sch->q); | |
543 | sch->ops = ops; | |
544 | sch->enqueue = ops->enqueue; | |
545 | sch->dequeue = ops->dequeue; | |
bb949fbd | 546 | sch->dev_queue = dev_queue; |
5ce2d488 | 547 | dev_hold(qdisc_dev(sch)); |
1da177e4 | 548 | atomic_set(&sch->refcnt, 1); |
3d54b82f TG |
549 | |
550 | return sch; | |
551 | errout: | |
01e123d7 | 552 | return ERR_PTR(err); |
3d54b82f TG |
553 | } |
554 | ||
bb949fbd DM |
555 | struct Qdisc * qdisc_create_dflt(struct net_device *dev, |
556 | struct netdev_queue *dev_queue, | |
557 | struct Qdisc_ops *ops, | |
9f9afec4 | 558 | unsigned int parentid) |
3d54b82f TG |
559 | { |
560 | struct Qdisc *sch; | |
10297b99 | 561 | |
5ce2d488 | 562 | sch = qdisc_alloc(dev_queue, ops); |
3d54b82f TG |
563 | if (IS_ERR(sch)) |
564 | goto errout; | |
9f9afec4 | 565 | sch->parent = parentid; |
3d54b82f | 566 | |
1da177e4 LT |
567 | if (!ops->init || ops->init(sch, NULL) == 0) |
568 | return sch; | |
569 | ||
0fbbeb1b | 570 | qdisc_destroy(sch); |
3d54b82f | 571 | errout: |
1da177e4 LT |
572 | return NULL; |
573 | } | |
62e3ba1b | 574 | EXPORT_SYMBOL(qdisc_create_dflt); |
1da177e4 | 575 | |
5fb66229 | 576 | /* Under qdisc_lock(qdisc) and BH! */ |
1da177e4 LT |
577 | |
578 | void qdisc_reset(struct Qdisc *qdisc) | |
579 | { | |
20fea08b | 580 | const struct Qdisc_ops *ops = qdisc->ops; |
1da177e4 LT |
581 | |
582 | if (ops->reset) | |
583 | ops->reset(qdisc); | |
67305ebc | 584 | |
bbd8a0d3 KK |
585 | if (qdisc->gso_skb) { |
586 | kfree_skb(qdisc->gso_skb); | |
587 | qdisc->gso_skb = NULL; | |
588 | qdisc->q.qlen = 0; | |
589 | } | |
1da177e4 | 590 | } |
62e3ba1b | 591 | EXPORT_SYMBOL(qdisc_reset); |
1da177e4 | 592 | |
1e0d5a57 | 593 | void qdisc_destroy(struct Qdisc *qdisc) |
1da177e4 | 594 | { |
8a34c5dc DM |
595 | const struct Qdisc_ops *ops = qdisc->ops; |
596 | ||
1e0d5a57 DM |
597 | if (qdisc->flags & TCQ_F_BUILTIN || |
598 | !atomic_dec_and_test(&qdisc->refcnt)) | |
599 | return; | |
600 | ||
3a682fbd | 601 | #ifdef CONFIG_NET_SCHED |
f6e0b239 JP |
602 | qdisc_list_del(qdisc); |
603 | ||
175f9c1b | 604 | qdisc_put_stab(qdisc->stab); |
3a682fbd | 605 | #endif |
8a34c5dc DM |
606 | gen_kill_estimator(&qdisc->bstats, &qdisc->rate_est); |
607 | if (ops->reset) | |
608 | ops->reset(qdisc); | |
609 | if (ops->destroy) | |
610 | ops->destroy(qdisc); | |
611 | ||
612 | module_put(ops->owner); | |
613 | dev_put(qdisc_dev(qdisc)); | |
614 | ||
554794de | 615 | kfree_skb(qdisc->gso_skb); |
1da177e4 LT |
616 | kfree((char *) qdisc - qdisc->padded); |
617 | } | |
62e3ba1b | 618 | EXPORT_SYMBOL(qdisc_destroy); |
1da177e4 | 619 | |
589983cd PM |
620 | /* Attach toplevel qdisc to device queue. */ |
621 | struct Qdisc *dev_graft_qdisc(struct netdev_queue *dev_queue, | |
622 | struct Qdisc *qdisc) | |
623 | { | |
624 | struct Qdisc *oqdisc = dev_queue->qdisc_sleeping; | |
625 | spinlock_t *root_lock; | |
626 | ||
627 | root_lock = qdisc_lock(oqdisc); | |
628 | spin_lock_bh(root_lock); | |
629 | ||
630 | /* Prune old scheduler */ | |
631 | if (oqdisc && atomic_read(&oqdisc->refcnt) <= 1) | |
632 | qdisc_reset(oqdisc); | |
633 | ||
634 | /* ... and graft new one */ | |
635 | if (qdisc == NULL) | |
636 | qdisc = &noop_qdisc; | |
637 | dev_queue->qdisc_sleeping = qdisc; | |
638 | rcu_assign_pointer(dev_queue->qdisc, &noop_qdisc); | |
639 | ||
640 | spin_unlock_bh(root_lock); | |
641 | ||
642 | return oqdisc; | |
643 | } | |
644 | ||
e8a0464c DM |
645 | static void attach_one_default_qdisc(struct net_device *dev, |
646 | struct netdev_queue *dev_queue, | |
647 | void *_unused) | |
648 | { | |
649 | struct Qdisc *qdisc; | |
650 | ||
651 | if (dev->tx_queue_len) { | |
652 | qdisc = qdisc_create_dflt(dev, dev_queue, | |
d3678b46 | 653 | &pfifo_fast_ops, TC_H_ROOT); |
e8a0464c DM |
654 | if (!qdisc) { |
655 | printk(KERN_INFO "%s: activation failed\n", dev->name); | |
656 | return; | |
657 | } | |
bbd8a0d3 KK |
658 | |
659 | /* Can by-pass the queue discipline for default qdisc */ | |
660 | qdisc->flags |= TCQ_F_CAN_BYPASS; | |
e8a0464c DM |
661 | } else { |
662 | qdisc = &noqueue_qdisc; | |
663 | } | |
664 | dev_queue->qdisc_sleeping = qdisc; | |
665 | } | |
666 | ||
6ec1c69a DM |
667 | static void attach_default_qdiscs(struct net_device *dev) |
668 | { | |
669 | struct netdev_queue *txq; | |
670 | struct Qdisc *qdisc; | |
671 | ||
672 | txq = netdev_get_tx_queue(dev, 0); | |
673 | ||
674 | if (!netif_is_multiqueue(dev) || dev->tx_queue_len == 0) { | |
675 | netdev_for_each_tx_queue(dev, attach_one_default_qdisc, NULL); | |
676 | dev->qdisc = txq->qdisc_sleeping; | |
677 | atomic_inc(&dev->qdisc->refcnt); | |
678 | } else { | |
679 | qdisc = qdisc_create_dflt(dev, txq, &mq_qdisc_ops, TC_H_ROOT); | |
680 | if (qdisc) { | |
681 | qdisc->ops->attach(qdisc); | |
682 | dev->qdisc = qdisc; | |
683 | } | |
684 | } | |
685 | } | |
686 | ||
e8a0464c DM |
687 | static void transition_one_qdisc(struct net_device *dev, |
688 | struct netdev_queue *dev_queue, | |
689 | void *_need_watchdog) | |
690 | { | |
83874000 | 691 | struct Qdisc *new_qdisc = dev_queue->qdisc_sleeping; |
e8a0464c DM |
692 | int *need_watchdog_p = _need_watchdog; |
693 | ||
a9312ae8 DM |
694 | if (!(new_qdisc->flags & TCQ_F_BUILTIN)) |
695 | clear_bit(__QDISC_STATE_DEACTIVATED, &new_qdisc->state); | |
696 | ||
83874000 | 697 | rcu_assign_pointer(dev_queue->qdisc, new_qdisc); |
9d21493b ED |
698 | if (need_watchdog_p && new_qdisc != &noqueue_qdisc) { |
699 | dev_queue->trans_start = 0; | |
e8a0464c | 700 | *need_watchdog_p = 1; |
9d21493b | 701 | } |
e8a0464c DM |
702 | } |
703 | ||
1da177e4 LT |
704 | void dev_activate(struct net_device *dev) |
705 | { | |
e8a0464c | 706 | int need_watchdog; |
b0e1e646 | 707 | |
1da177e4 | 708 | /* No queueing discipline is attached to device; |
d3678b46 DM |
709 | create default one i.e. pfifo_fast for devices, |
710 | which need queueing and noqueue_qdisc for | |
711 | virtual interfaces | |
1da177e4 LT |
712 | */ |
713 | ||
6ec1c69a DM |
714 | if (dev->qdisc == &noop_qdisc) |
715 | attach_default_qdiscs(dev); | |
af356afa | 716 | |
cacaddf5 TC |
717 | if (!netif_carrier_ok(dev)) |
718 | /* Delay activation until next carrier-on event */ | |
719 | return; | |
720 | ||
e8a0464c DM |
721 | need_watchdog = 0; |
722 | netdev_for_each_tx_queue(dev, transition_one_qdisc, &need_watchdog); | |
8d50b53d | 723 | transition_one_qdisc(dev, &dev->rx_queue, NULL); |
e8a0464c DM |
724 | |
725 | if (need_watchdog) { | |
1da177e4 LT |
726 | dev->trans_start = jiffies; |
727 | dev_watchdog_up(dev); | |
728 | } | |
b0e1e646 DM |
729 | } |
730 | ||
e8a0464c DM |
731 | static void dev_deactivate_queue(struct net_device *dev, |
732 | struct netdev_queue *dev_queue, | |
733 | void *_qdisc_default) | |
b0e1e646 | 734 | { |
e8a0464c | 735 | struct Qdisc *qdisc_default = _qdisc_default; |
970565bb | 736 | struct Qdisc *qdisc; |
970565bb | 737 | |
970565bb | 738 | qdisc = dev_queue->qdisc; |
b0e1e646 | 739 | if (qdisc) { |
83874000 DM |
740 | spin_lock_bh(qdisc_lock(qdisc)); |
741 | ||
a9312ae8 DM |
742 | if (!(qdisc->flags & TCQ_F_BUILTIN)) |
743 | set_bit(__QDISC_STATE_DEACTIVATED, &qdisc->state); | |
744 | ||
f7a54c13 | 745 | rcu_assign_pointer(dev_queue->qdisc, qdisc_default); |
b0e1e646 | 746 | qdisc_reset(qdisc); |
d3b753db | 747 | |
83874000 | 748 | spin_unlock_bh(qdisc_lock(qdisc)); |
b0e1e646 | 749 | } |
1da177e4 LT |
750 | } |
751 | ||
4335cd2d | 752 | static bool some_qdisc_is_busy(struct net_device *dev) |
e8a0464c DM |
753 | { |
754 | unsigned int i; | |
755 | ||
756 | for (i = 0; i < dev->num_tx_queues; i++) { | |
757 | struct netdev_queue *dev_queue; | |
7698b4fc | 758 | spinlock_t *root_lock; |
e2627c8c | 759 | struct Qdisc *q; |
e8a0464c DM |
760 | int val; |
761 | ||
762 | dev_queue = netdev_get_tx_queue(dev, i); | |
b9a3b110 | 763 | q = dev_queue->qdisc_sleeping; |
5fb66229 | 764 | root_lock = qdisc_lock(q); |
e8a0464c | 765 | |
4335cd2d | 766 | spin_lock_bh(root_lock); |
e8a0464c | 767 | |
b9a3b110 DM |
768 | val = (test_bit(__QDISC_STATE_RUNNING, &q->state) || |
769 | test_bit(__QDISC_STATE_SCHED, &q->state)); | |
e8a0464c | 770 | |
4335cd2d | 771 | spin_unlock_bh(root_lock); |
e8a0464c DM |
772 | |
773 | if (val) | |
774 | return true; | |
775 | } | |
776 | return false; | |
777 | } | |
778 | ||
1da177e4 LT |
779 | void dev_deactivate(struct net_device *dev) |
780 | { | |
e8a0464c | 781 | netdev_for_each_tx_queue(dev, dev_deactivate_queue, &noop_qdisc); |
8d50b53d | 782 | dev_deactivate_queue(dev, &dev->rx_queue, &noop_qdisc); |
41a23b07 | 783 | |
1da177e4 LT |
784 | dev_watchdog_down(dev); |
785 | ||
ce0e32e6 | 786 | /* Wait for outstanding qdisc-less dev_queue_xmit calls. */ |
d4828d85 | 787 | synchronize_rcu(); |
1da177e4 | 788 | |
d4828d85 | 789 | /* Wait for outstanding qdisc_run calls. */ |
4335cd2d DM |
790 | while (some_qdisc_is_busy(dev)) |
791 | yield(); | |
1da177e4 LT |
792 | } |
793 | ||
b0e1e646 DM |
794 | static void dev_init_scheduler_queue(struct net_device *dev, |
795 | struct netdev_queue *dev_queue, | |
e8a0464c | 796 | void *_qdisc) |
b0e1e646 | 797 | { |
e8a0464c DM |
798 | struct Qdisc *qdisc = _qdisc; |
799 | ||
b0e1e646 DM |
800 | dev_queue->qdisc = qdisc; |
801 | dev_queue->qdisc_sleeping = qdisc; | |
b0e1e646 DM |
802 | } |
803 | ||
1da177e4 LT |
804 | void dev_init_scheduler(struct net_device *dev) |
805 | { | |
af356afa | 806 | dev->qdisc = &noop_qdisc; |
e8a0464c | 807 | netdev_for_each_tx_queue(dev, dev_init_scheduler_queue, &noop_qdisc); |
8d50b53d | 808 | dev_init_scheduler_queue(dev, &dev->rx_queue, &noop_qdisc); |
1da177e4 | 809 | |
b24b8a24 | 810 | setup_timer(&dev->watchdog_timer, dev_watchdog, (unsigned long)dev); |
1da177e4 LT |
811 | } |
812 | ||
e8a0464c DM |
813 | static void shutdown_scheduler_queue(struct net_device *dev, |
814 | struct netdev_queue *dev_queue, | |
815 | void *_qdisc_default) | |
1da177e4 | 816 | { |
b0e1e646 | 817 | struct Qdisc *qdisc = dev_queue->qdisc_sleeping; |
e8a0464c | 818 | struct Qdisc *qdisc_default = _qdisc_default; |
b0e1e646 DM |
819 | |
820 | if (qdisc) { | |
f7a54c13 | 821 | rcu_assign_pointer(dev_queue->qdisc, qdisc_default); |
b0e1e646 | 822 | dev_queue->qdisc_sleeping = qdisc_default; |
1da177e4 | 823 | |
1da177e4 | 824 | qdisc_destroy(qdisc); |
10297b99 | 825 | } |
b0e1e646 DM |
826 | } |
827 | ||
828 | void dev_shutdown(struct net_device *dev) | |
829 | { | |
e8a0464c | 830 | netdev_for_each_tx_queue(dev, shutdown_scheduler_queue, &noop_qdisc); |
8d50b53d | 831 | shutdown_scheduler_queue(dev, &dev->rx_queue, &noop_qdisc); |
af356afa PM |
832 | qdisc_destroy(dev->qdisc); |
833 | dev->qdisc = &noop_qdisc; | |
834 | ||
547b792c | 835 | WARN_ON(timer_pending(&dev->watchdog_timer)); |
1da177e4 | 836 | } |