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> | |
5a0e3ad6 | 27 | #include <linux/slab.h> |
07ce76aa | 28 | #include <linux/if_vlan.h> |
292f1c7f | 29 | #include <net/sch_generic.h> |
1da177e4 | 30 | #include <net/pkt_sched.h> |
7fee226a | 31 | #include <net/dst.h> |
e543002f | 32 | #include <trace/events/qdisc.h> |
1da177e4 | 33 | |
34aedd3f | 34 | /* Qdisc to use by default */ |
35 | const struct Qdisc_ops *default_qdisc_ops = &pfifo_fast_ops; | |
36 | EXPORT_SYMBOL(default_qdisc_ops); | |
37 | ||
1da177e4 LT |
38 | /* Main transmission queue. */ |
39 | ||
0463d4ae | 40 | /* Modifications to data participating in scheduling must be protected with |
5fb66229 | 41 | * qdisc_lock(qdisc) spinlock. |
0463d4ae PM |
42 | * |
43 | * The idea is the following: | |
c7e4f3bb DM |
44 | * - enqueue, dequeue are serialized via qdisc root lock |
45 | * - ingress filtering is also serialized via qdisc root lock | |
0463d4ae | 46 | * - updates to tree and tree walking are only done under the rtnl mutex. |
1da177e4 | 47 | */ |
70e57d5e JF |
48 | |
49 | static inline struct sk_buff *__skb_dequeue_bad_txq(struct Qdisc *q) | |
50 | { | |
51 | const struct netdev_queue *txq = q->dev_queue; | |
52 | spinlock_t *lock = NULL; | |
53 | struct sk_buff *skb; | |
54 | ||
55 | if (q->flags & TCQ_F_NOLOCK) { | |
56 | lock = qdisc_lock(q); | |
57 | spin_lock(lock); | |
58 | } | |
59 | ||
60 | skb = skb_peek(&q->skb_bad_txq); | |
61 | if (skb) { | |
62 | /* check the reason of requeuing without tx lock first */ | |
63 | txq = skb_get_tx_queue(txq->dev, skb); | |
64 | if (!netif_xmit_frozen_or_stopped(txq)) { | |
65 | skb = __skb_dequeue(&q->skb_bad_txq); | |
66 | if (qdisc_is_percpu_stats(q)) { | |
67 | qdisc_qstats_cpu_backlog_dec(q, skb); | |
68 | qdisc_qstats_cpu_qlen_dec(q); | |
69 | } else { | |
70 | qdisc_qstats_backlog_dec(q, skb); | |
71 | q->q.qlen--; | |
72 | } | |
73 | } else { | |
74 | skb = NULL; | |
75 | } | |
76 | } | |
77 | ||
78 | if (lock) | |
79 | spin_unlock(lock); | |
80 | ||
81 | return skb; | |
82 | } | |
83 | ||
84 | static inline struct sk_buff *qdisc_dequeue_skb_bad_txq(struct Qdisc *q) | |
85 | { | |
86 | struct sk_buff *skb = skb_peek(&q->skb_bad_txq); | |
87 | ||
88 | if (unlikely(skb)) | |
89 | skb = __skb_dequeue_bad_txq(q); | |
90 | ||
91 | return skb; | |
92 | } | |
93 | ||
94 | static inline void qdisc_enqueue_skb_bad_txq(struct Qdisc *q, | |
95 | struct sk_buff *skb) | |
96 | { | |
97 | spinlock_t *lock = NULL; | |
98 | ||
99 | if (q->flags & TCQ_F_NOLOCK) { | |
100 | lock = qdisc_lock(q); | |
101 | spin_lock(lock); | |
102 | } | |
103 | ||
104 | __skb_queue_tail(&q->skb_bad_txq, skb); | |
105 | ||
106 | if (lock) | |
107 | spin_unlock(lock); | |
108 | } | |
109 | ||
a53851e2 | 110 | static inline int __dev_requeue_skb(struct sk_buff *skb, struct Qdisc *q) |
c716a81a | 111 | { |
a53851e2 | 112 | __skb_queue_head(&q->gso_skb, skb); |
53e91503 | 113 | q->qstats.requeues++; |
a27758ff | 114 | qdisc_qstats_backlog_inc(q, skb); |
bbd8a0d3 | 115 | q->q.qlen++; /* it's still part of the queue */ |
37437bb2 | 116 | __netif_schedule(q); |
6252352d | 117 | |
c716a81a JHS |
118 | return 0; |
119 | } | |
120 | ||
a53851e2 JF |
121 | static inline int dev_requeue_skb_locked(struct sk_buff *skb, struct Qdisc *q) |
122 | { | |
123 | spinlock_t *lock = qdisc_lock(q); | |
124 | ||
125 | spin_lock(lock); | |
126 | __skb_queue_tail(&q->gso_skb, skb); | |
127 | spin_unlock(lock); | |
128 | ||
129 | qdisc_qstats_cpu_requeues_inc(q); | |
130 | qdisc_qstats_cpu_backlog_inc(q, skb); | |
131 | qdisc_qstats_cpu_qlen_inc(q); | |
132 | __netif_schedule(q); | |
133 | ||
134 | return 0; | |
135 | } | |
136 | ||
137 | static inline int dev_requeue_skb(struct sk_buff *skb, struct Qdisc *q) | |
138 | { | |
139 | if (q->flags & TCQ_F_NOLOCK) | |
140 | return dev_requeue_skb_locked(skb, q); | |
141 | else | |
142 | return __dev_requeue_skb(skb, q); | |
143 | } | |
144 | ||
55a93b3e ED |
145 | static void try_bulk_dequeue_skb(struct Qdisc *q, |
146 | struct sk_buff *skb, | |
b8358d70 JDB |
147 | const struct netdev_queue *txq, |
148 | int *packets) | |
5772e9a3 | 149 | { |
55a93b3e | 150 | int bytelimit = qdisc_avail_bulklimit(txq) - skb->len; |
5772e9a3 JDB |
151 | |
152 | while (bytelimit > 0) { | |
55a93b3e | 153 | struct sk_buff *nskb = q->dequeue(q); |
5772e9a3 | 154 | |
55a93b3e | 155 | if (!nskb) |
5772e9a3 JDB |
156 | break; |
157 | ||
55a93b3e ED |
158 | bytelimit -= nskb->len; /* covers GSO len */ |
159 | skb->next = nskb; | |
160 | skb = nskb; | |
b8358d70 | 161 | (*packets)++; /* GSO counts as one pkt */ |
5772e9a3 | 162 | } |
55a93b3e | 163 | skb->next = NULL; |
5772e9a3 JDB |
164 | } |
165 | ||
4d202a0d ED |
166 | /* This variant of try_bulk_dequeue_skb() makes sure |
167 | * all skbs in the chain are for the same txq | |
168 | */ | |
169 | static void try_bulk_dequeue_skb_slow(struct Qdisc *q, | |
170 | struct sk_buff *skb, | |
171 | int *packets) | |
172 | { | |
173 | int mapping = skb_get_queue_mapping(skb); | |
174 | struct sk_buff *nskb; | |
175 | int cnt = 0; | |
176 | ||
177 | do { | |
178 | nskb = q->dequeue(q); | |
179 | if (!nskb) | |
180 | break; | |
181 | if (unlikely(skb_get_queue_mapping(nskb) != mapping)) { | |
70e57d5e JF |
182 | qdisc_enqueue_skb_bad_txq(q, nskb); |
183 | ||
184 | if (qdisc_is_percpu_stats(q)) { | |
185 | qdisc_qstats_cpu_backlog_inc(q, nskb); | |
186 | qdisc_qstats_cpu_qlen_inc(q); | |
187 | } else { | |
188 | qdisc_qstats_backlog_inc(q, nskb); | |
189 | q->q.qlen++; | |
190 | } | |
4d202a0d ED |
191 | break; |
192 | } | |
193 | skb->next = nskb; | |
194 | skb = nskb; | |
195 | } while (++cnt < 8); | |
196 | (*packets) += cnt; | |
197 | skb->next = NULL; | |
198 | } | |
199 | ||
5772e9a3 JDB |
200 | /* Note that dequeue_skb can possibly return a SKB list (via skb->next). |
201 | * A requeued skb (via q->gso_skb) can also be a SKB list. | |
202 | */ | |
b8358d70 JDB |
203 | static struct sk_buff *dequeue_skb(struct Qdisc *q, bool *validate, |
204 | int *packets) | |
c716a81a | 205 | { |
1abbe139 | 206 | const struct netdev_queue *txq = q->dev_queue; |
fd8e8d1a | 207 | struct sk_buff *skb = NULL; |
554794de | 208 | |
b8358d70 | 209 | *packets = 1; |
a53851e2 JF |
210 | if (unlikely(!skb_queue_empty(&q->gso_skb))) { |
211 | spinlock_t *lock = NULL; | |
212 | ||
213 | if (q->flags & TCQ_F_NOLOCK) { | |
214 | lock = qdisc_lock(q); | |
215 | spin_lock(lock); | |
216 | } | |
217 | ||
218 | skb = skb_peek(&q->gso_skb); | |
219 | ||
220 | /* skb may be null if another cpu pulls gso_skb off in between | |
221 | * empty check and lock. | |
222 | */ | |
223 | if (!skb) { | |
224 | if (lock) | |
225 | spin_unlock(lock); | |
226 | goto validate; | |
227 | } | |
228 | ||
4d202a0d ED |
229 | /* skb in gso_skb were already validated */ |
230 | *validate = false; | |
ebf05982 | 231 | /* check the reason of requeuing without tx lock first */ |
10c51b56 | 232 | txq = skb_get_tx_queue(txq->dev, skb); |
73466498 | 233 | if (!netif_xmit_frozen_or_stopped(txq)) { |
a53851e2 JF |
234 | skb = __skb_dequeue(&q->gso_skb); |
235 | if (qdisc_is_percpu_stats(q)) { | |
236 | qdisc_qstats_cpu_backlog_dec(q, skb); | |
237 | qdisc_qstats_cpu_qlen_dec(q); | |
238 | } else { | |
239 | qdisc_qstats_backlog_dec(q, skb); | |
240 | q->q.qlen--; | |
241 | } | |
242 | } else { | |
ebf05982 | 243 | skb = NULL; |
a53851e2 JF |
244 | } |
245 | if (lock) | |
246 | spin_unlock(lock); | |
e543002f | 247 | goto trace; |
4d202a0d | 248 | } |
a53851e2 | 249 | validate: |
4d202a0d | 250 | *validate = true; |
fd8e8d1a JF |
251 | |
252 | if ((q->flags & TCQ_F_ONETXQUEUE) && | |
253 | netif_xmit_frozen_or_stopped(txq)) | |
254 | return skb; | |
255 | ||
70e57d5e JF |
256 | skb = qdisc_dequeue_skb_bad_txq(q); |
257 | if (unlikely(skb)) | |
258 | goto bulk; | |
fd8e8d1a | 259 | skb = q->dequeue(q); |
4d202a0d ED |
260 | if (skb) { |
261 | bulk: | |
262 | if (qdisc_may_bulk(q)) | |
263 | try_bulk_dequeue_skb(q, skb, txq, packets); | |
264 | else | |
265 | try_bulk_dequeue_skb_slow(q, skb, packets); | |
ebf05982 | 266 | } |
e543002f JDB |
267 | trace: |
268 | trace_qdisc_dequeue(q, txq, *packets, skb); | |
c716a81a JHS |
269 | return skb; |
270 | } | |
271 | ||
10297b99 | 272 | /* |
10770bc2 | 273 | * Transmit possibly several skbs, and handle the return status as |
f9eb8aea | 274 | * required. Owning running seqcount bit guarantees that |
10770bc2 | 275 | * only one CPU can execute this function. |
6c1361a6 KK |
276 | * |
277 | * Returns to the caller: | |
29b86cda JF |
278 | * false - hardware queue frozen backoff |
279 | * true - feel free to send more pkts | |
6c1361a6 | 280 | */ |
29b86cda JF |
281 | bool sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q, |
282 | struct net_device *dev, struct netdev_queue *txq, | |
283 | spinlock_t *root_lock, bool validate) | |
1da177e4 | 284 | { |
5f1a485d | 285 | int ret = NETDEV_TX_BUSY; |
7698b4fc DM |
286 | |
287 | /* And release qdisc */ | |
6b3ba914 JF |
288 | if (root_lock) |
289 | spin_unlock(root_lock); | |
c716a81a | 290 | |
55a93b3e ED |
291 | /* Note that we validate skb (GSO, checksum, ...) outside of locks */ |
292 | if (validate) | |
293 | skb = validate_xmit_skb_list(skb, dev); | |
572a9d7b | 294 | |
3dcd493f | 295 | if (likely(skb)) { |
55a93b3e ED |
296 | HARD_TX_LOCK(dev, txq, smp_processor_id()); |
297 | if (!netif_xmit_frozen_or_stopped(txq)) | |
298 | skb = dev_hard_start_xmit(skb, dev, txq, &ret); | |
c716a81a | 299 | |
55a93b3e | 300 | HARD_TX_UNLOCK(dev, txq); |
3dcd493f | 301 | } else { |
6b3ba914 JF |
302 | if (root_lock) |
303 | spin_lock(root_lock); | |
29b86cda | 304 | return true; |
55a93b3e | 305 | } |
6b3ba914 JF |
306 | |
307 | if (root_lock) | |
308 | spin_lock(root_lock); | |
c716a81a | 309 | |
29b86cda | 310 | if (!dev_xmit_complete(ret)) { |
6c1361a6 | 311 | /* Driver returned NETDEV_TX_BUSY - requeue skb */ |
e87cc472 JP |
312 | if (unlikely(ret != NETDEV_TX_BUSY)) |
313 | net_warn_ratelimited("BUG %s code %d qlen %d\n", | |
314 | dev->name, ret, q->q.qlen); | |
6c1361a6 | 315 | |
29b86cda JF |
316 | dev_requeue_skb(skb, q); |
317 | return false; | |
6c1361a6 | 318 | } |
c716a81a | 319 | |
73466498 | 320 | if (ret && netif_xmit_frozen_or_stopped(txq)) |
29b86cda | 321 | return false; |
37437bb2 | 322 | |
29b86cda | 323 | return true; |
1da177e4 LT |
324 | } |
325 | ||
bbd8a0d3 KK |
326 | /* |
327 | * NOTE: Called under qdisc_lock(q) with locally disabled BH. | |
328 | * | |
f9eb8aea | 329 | * running seqcount guarantees only one CPU can process |
bbd8a0d3 KK |
330 | * this qdisc at a time. qdisc_lock(q) serializes queue accesses for |
331 | * this queue. | |
332 | * | |
333 | * netif_tx_lock serializes accesses to device driver. | |
334 | * | |
335 | * qdisc_lock(q) and netif_tx_lock are mutually exclusive, | |
336 | * if one is grabbed, another must be free. | |
337 | * | |
338 | * Note, that this procedure can be called by a watchdog timer | |
339 | * | |
340 | * Returns to the caller: | |
341 | * 0 - queue is empty or throttled. | |
342 | * >0 - queue is not empty. | |
343 | * | |
344 | */ | |
29b86cda | 345 | static inline bool qdisc_restart(struct Qdisc *q, int *packets) |
bbd8a0d3 | 346 | { |
6b3ba914 | 347 | spinlock_t *root_lock = NULL; |
bbd8a0d3 KK |
348 | struct netdev_queue *txq; |
349 | struct net_device *dev; | |
bbd8a0d3 | 350 | struct sk_buff *skb; |
55a93b3e | 351 | bool validate; |
bbd8a0d3 KK |
352 | |
353 | /* Dequeue packet */ | |
b8358d70 | 354 | skb = dequeue_skb(q, &validate, packets); |
bbd8a0d3 | 355 | if (unlikely(!skb)) |
29b86cda | 356 | return false; |
10c51b56 | 357 | |
6b3ba914 JF |
358 | if (!(q->flags & TCQ_F_NOLOCK)) |
359 | root_lock = qdisc_lock(q); | |
360 | ||
bbd8a0d3 | 361 | dev = qdisc_dev(q); |
10c51b56 | 362 | txq = skb_get_tx_queue(dev, skb); |
bbd8a0d3 | 363 | |
55a93b3e | 364 | return sch_direct_xmit(skb, q, dev, txq, root_lock, validate); |
bbd8a0d3 KK |
365 | } |
366 | ||
37437bb2 | 367 | void __qdisc_run(struct Qdisc *q) |
48d83325 | 368 | { |
3d48b53f | 369 | int quota = dev_tx_weight; |
b8358d70 | 370 | int packets; |
2ba2506c | 371 | |
b8358d70 | 372 | while (qdisc_restart(q, &packets)) { |
2ba2506c | 373 | /* |
d5b8aa1d | 374 | * Ordered by possible occurrence: Postpone processing if |
375 | * 1. we've exceeded packet quota | |
376 | * 2. another process needs the CPU; | |
2ba2506c | 377 | */ |
b8358d70 JDB |
378 | quota -= packets; |
379 | if (quota <= 0 || need_resched()) { | |
37437bb2 | 380 | __netif_schedule(q); |
d90df3ad | 381 | break; |
2ba2506c HX |
382 | } |
383 | } | |
48d83325 HX |
384 | } |
385 | ||
9d21493b ED |
386 | unsigned long dev_trans_start(struct net_device *dev) |
387 | { | |
07ce76aa | 388 | unsigned long val, res; |
9d21493b ED |
389 | unsigned int i; |
390 | ||
07ce76aa | 391 | if (is_vlan_dev(dev)) |
392 | dev = vlan_dev_real_dev(dev); | |
9b36627a FW |
393 | res = netdev_get_tx_queue(dev, 0)->trans_start; |
394 | for (i = 1; i < dev->num_tx_queues; i++) { | |
9d21493b ED |
395 | val = netdev_get_tx_queue(dev, i)->trans_start; |
396 | if (val && time_after(val, res)) | |
397 | res = val; | |
398 | } | |
07ce76aa | 399 | |
9d21493b ED |
400 | return res; |
401 | } | |
402 | EXPORT_SYMBOL(dev_trans_start); | |
403 | ||
cdeabbb8 | 404 | static void dev_watchdog(struct timer_list *t) |
1da177e4 | 405 | { |
cdeabbb8 | 406 | struct net_device *dev = from_timer(dev, t, watchdog_timer); |
1da177e4 | 407 | |
932ff279 | 408 | netif_tx_lock(dev); |
e8a0464c | 409 | if (!qdisc_tx_is_noop(dev)) { |
1da177e4 LT |
410 | if (netif_device_present(dev) && |
411 | netif_running(dev) && | |
412 | netif_carrier_ok(dev)) { | |
9d21493b | 413 | int some_queue_timedout = 0; |
e8a0464c | 414 | unsigned int i; |
9d21493b | 415 | unsigned long trans_start; |
e8a0464c DM |
416 | |
417 | for (i = 0; i < dev->num_tx_queues; i++) { | |
418 | struct netdev_queue *txq; | |
419 | ||
420 | txq = netdev_get_tx_queue(dev, i); | |
9b36627a | 421 | trans_start = txq->trans_start; |
73466498 | 422 | if (netif_xmit_stopped(txq) && |
9d21493b ED |
423 | time_after(jiffies, (trans_start + |
424 | dev->watchdog_timeo))) { | |
425 | some_queue_timedout = 1; | |
ccf5ff69 | 426 | txq->trans_timeout++; |
e8a0464c DM |
427 | break; |
428 | } | |
429 | } | |
338f7566 | 430 | |
9d21493b | 431 | if (some_queue_timedout) { |
9d21493b | 432 | WARN_ONCE(1, KERN_INFO "NETDEV WATCHDOG: %s (%s): transmit queue %u timed out\n", |
3019de12 | 433 | dev->name, netdev_drivername(dev), i); |
d314774c | 434 | dev->netdev_ops->ndo_tx_timeout(dev); |
1da177e4 | 435 | } |
e8a0464c DM |
436 | if (!mod_timer(&dev->watchdog_timer, |
437 | round_jiffies(jiffies + | |
438 | dev->watchdog_timeo))) | |
1da177e4 LT |
439 | dev_hold(dev); |
440 | } | |
441 | } | |
932ff279 | 442 | netif_tx_unlock(dev); |
1da177e4 LT |
443 | |
444 | dev_put(dev); | |
445 | } | |
446 | ||
1da177e4 LT |
447 | void __netdev_watchdog_up(struct net_device *dev) |
448 | { | |
d314774c | 449 | if (dev->netdev_ops->ndo_tx_timeout) { |
1da177e4 LT |
450 | if (dev->watchdog_timeo <= 0) |
451 | dev->watchdog_timeo = 5*HZ; | |
60468d5b VP |
452 | if (!mod_timer(&dev->watchdog_timer, |
453 | round_jiffies(jiffies + dev->watchdog_timeo))) | |
1da177e4 LT |
454 | dev_hold(dev); |
455 | } | |
456 | } | |
457 | ||
458 | static void dev_watchdog_up(struct net_device *dev) | |
459 | { | |
1da177e4 | 460 | __netdev_watchdog_up(dev); |
1da177e4 LT |
461 | } |
462 | ||
463 | static void dev_watchdog_down(struct net_device *dev) | |
464 | { | |
932ff279 | 465 | netif_tx_lock_bh(dev); |
1da177e4 | 466 | if (del_timer(&dev->watchdog_timer)) |
15333061 | 467 | dev_put(dev); |
932ff279 | 468 | netif_tx_unlock_bh(dev); |
1da177e4 LT |
469 | } |
470 | ||
bea3348e SH |
471 | /** |
472 | * netif_carrier_on - set carrier | |
473 | * @dev: network device | |
474 | * | |
475 | * Device has detected that carrier. | |
476 | */ | |
0a242efc DV |
477 | void netif_carrier_on(struct net_device *dev) |
478 | { | |
bfaae0f0 | 479 | if (test_and_clear_bit(__LINK_STATE_NOCARRIER, &dev->state)) { |
b4730016 DM |
480 | if (dev->reg_state == NETREG_UNINITIALIZED) |
481 | return; | |
2d3b479d | 482 | atomic_inc(&dev->carrier_changes); |
0a242efc | 483 | linkwatch_fire_event(dev); |
bfaae0f0 JG |
484 | if (netif_running(dev)) |
485 | __netdev_watchdog_up(dev); | |
486 | } | |
0a242efc | 487 | } |
62e3ba1b | 488 | EXPORT_SYMBOL(netif_carrier_on); |
0a242efc | 489 | |
bea3348e SH |
490 | /** |
491 | * netif_carrier_off - clear carrier | |
492 | * @dev: network device | |
493 | * | |
494 | * Device has detected loss of carrier. | |
495 | */ | |
0a242efc DV |
496 | void netif_carrier_off(struct net_device *dev) |
497 | { | |
b4730016 DM |
498 | if (!test_and_set_bit(__LINK_STATE_NOCARRIER, &dev->state)) { |
499 | if (dev->reg_state == NETREG_UNINITIALIZED) | |
500 | return; | |
2d3b479d | 501 | atomic_inc(&dev->carrier_changes); |
0a242efc | 502 | linkwatch_fire_event(dev); |
b4730016 | 503 | } |
0a242efc | 504 | } |
62e3ba1b | 505 | EXPORT_SYMBOL(netif_carrier_off); |
0a242efc | 506 | |
1da177e4 LT |
507 | /* "NOOP" scheduler: the best scheduler, recommended for all interfaces |
508 | under all circumstances. It is difficult to invent anything faster or | |
509 | cheaper. | |
510 | */ | |
511 | ||
520ac30f ED |
512 | static int noop_enqueue(struct sk_buff *skb, struct Qdisc *qdisc, |
513 | struct sk_buff **to_free) | |
1da177e4 | 514 | { |
520ac30f | 515 | __qdisc_drop(skb, to_free); |
1da177e4 LT |
516 | return NET_XMIT_CN; |
517 | } | |
518 | ||
82d567c2 | 519 | static struct sk_buff *noop_dequeue(struct Qdisc *qdisc) |
1da177e4 LT |
520 | { |
521 | return NULL; | |
522 | } | |
523 | ||
20fea08b | 524 | struct Qdisc_ops noop_qdisc_ops __read_mostly = { |
1da177e4 LT |
525 | .id = "noop", |
526 | .priv_size = 0, | |
527 | .enqueue = noop_enqueue, | |
528 | .dequeue = noop_dequeue, | |
99c0db26 | 529 | .peek = noop_dequeue, |
1da177e4 LT |
530 | .owner = THIS_MODULE, |
531 | }; | |
532 | ||
7698b4fc | 533 | static struct netdev_queue noop_netdev_queue = { |
7698b4fc | 534 | .qdisc = &noop_qdisc, |
9f3ffae0 | 535 | .qdisc_sleeping = &noop_qdisc, |
7698b4fc DM |
536 | }; |
537 | ||
1da177e4 LT |
538 | struct Qdisc noop_qdisc = { |
539 | .enqueue = noop_enqueue, | |
540 | .dequeue = noop_dequeue, | |
541 | .flags = TCQ_F_BUILTIN, | |
10297b99 | 542 | .ops = &noop_qdisc_ops, |
83874000 | 543 | .q.lock = __SPIN_LOCK_UNLOCKED(noop_qdisc.q.lock), |
7698b4fc | 544 | .dev_queue = &noop_netdev_queue, |
f9eb8aea | 545 | .running = SEQCNT_ZERO(noop_qdisc.running), |
7b5edbc4 | 546 | .busylock = __SPIN_LOCK_UNLOCKED(noop_qdisc.busylock), |
1da177e4 | 547 | }; |
62e3ba1b | 548 | EXPORT_SYMBOL(noop_qdisc); |
1da177e4 | 549 | |
d66d6c31 PS |
550 | static int noqueue_init(struct Qdisc *qdisc, struct nlattr *opt) |
551 | { | |
552 | /* register_qdisc() assigns a default of noop_enqueue if unset, | |
553 | * but __dev_queue_xmit() treats noqueue only as such | |
554 | * if this is NULL - so clear it here. */ | |
555 | qdisc->enqueue = NULL; | |
556 | return 0; | |
557 | } | |
558 | ||
559 | struct Qdisc_ops noqueue_qdisc_ops __read_mostly = { | |
1da177e4 LT |
560 | .id = "noqueue", |
561 | .priv_size = 0, | |
d66d6c31 | 562 | .init = noqueue_init, |
1da177e4 LT |
563 | .enqueue = noop_enqueue, |
564 | .dequeue = noop_dequeue, | |
99c0db26 | 565 | .peek = noop_dequeue, |
1da177e4 LT |
566 | .owner = THIS_MODULE, |
567 | }; | |
568 | ||
cc7ec456 ED |
569 | static const u8 prio2band[TC_PRIO_MAX + 1] = { |
570 | 1, 2, 2, 2, 1, 2, 0, 0 , 1, 1, 1, 1, 1, 1, 1, 1 | |
571 | }; | |
d3678b46 DM |
572 | |
573 | /* 3-band FIFO queue: old style, but should be a bit faster than | |
574 | generic prio+fifo combination. | |
575 | */ | |
576 | ||
577 | #define PFIFO_FAST_BANDS 3 | |
578 | ||
fd3ae5e8 KK |
579 | /* |
580 | * Private data for a pfifo_fast scheduler containing: | |
581 | * - queues for the three band | |
582 | * - bitmap indicating which of the bands contain skbs | |
583 | */ | |
584 | struct pfifo_fast_priv { | |
585 | u32 bitmap; | |
48da34b7 | 586 | struct qdisc_skb_head q[PFIFO_FAST_BANDS]; |
fd3ae5e8 KK |
587 | }; |
588 | ||
589 | /* | |
590 | * Convert a bitmap to the first band number where an skb is queued, where: | |
591 | * bitmap=0 means there are no skbs on any band. | |
592 | * bitmap=1 means there is an skb on band 0. | |
593 | * bitmap=7 means there are skbs on all 3 bands, etc. | |
594 | */ | |
595 | static const int bitmap2band[] = {-1, 0, 1, 0, 2, 0, 1, 0}; | |
596 | ||
48da34b7 | 597 | static inline struct qdisc_skb_head *band2list(struct pfifo_fast_priv *priv, |
fd3ae5e8 | 598 | int band) |
d3678b46 | 599 | { |
fd3ae5e8 | 600 | return priv->q + band; |
d3678b46 DM |
601 | } |
602 | ||
520ac30f ED |
603 | static int pfifo_fast_enqueue(struct sk_buff *skb, struct Qdisc *qdisc, |
604 | struct sk_buff **to_free) | |
321090e7 | 605 | { |
97d0678f | 606 | if (qdisc->q.qlen < qdisc_dev(qdisc)->tx_queue_len) { |
a453e068 KK |
607 | int band = prio2band[skb->priority & TC_PRIO_MAX]; |
608 | struct pfifo_fast_priv *priv = qdisc_priv(qdisc); | |
48da34b7 | 609 | struct qdisc_skb_head *list = band2list(priv, band); |
1da177e4 | 610 | |
fd3ae5e8 | 611 | priv->bitmap |= (1 << band); |
d3678b46 | 612 | qdisc->q.qlen++; |
821d24ae | 613 | return __qdisc_enqueue_tail(skb, qdisc, list); |
d3678b46 | 614 | } |
821d24ae | 615 | |
520ac30f | 616 | return qdisc_drop(skb, qdisc, to_free); |
1da177e4 LT |
617 | } |
618 | ||
cc7ec456 | 619 | static struct sk_buff *pfifo_fast_dequeue(struct Qdisc *qdisc) |
1da177e4 | 620 | { |
fd3ae5e8 KK |
621 | struct pfifo_fast_priv *priv = qdisc_priv(qdisc); |
622 | int band = bitmap2band[priv->bitmap]; | |
1da177e4 | 623 | |
fd3ae5e8 | 624 | if (likely(band >= 0)) { |
48da34b7 FW |
625 | struct qdisc_skb_head *qh = band2list(priv, band); |
626 | struct sk_buff *skb = __qdisc_dequeue_head(qh); | |
ec323368 FW |
627 | |
628 | if (likely(skb != NULL)) { | |
629 | qdisc_qstats_backlog_dec(qdisc, skb); | |
630 | qdisc_bstats_update(qdisc, skb); | |
631 | } | |
fd3ae5e8 KK |
632 | |
633 | qdisc->q.qlen--; | |
48da34b7 | 634 | if (qh->qlen == 0) |
fd3ae5e8 KK |
635 | priv->bitmap &= ~(1 << band); |
636 | ||
637 | return skb; | |
d3678b46 | 638 | } |
f87a9c3d | 639 | |
1da177e4 LT |
640 | return NULL; |
641 | } | |
642 | ||
cc7ec456 | 643 | static struct sk_buff *pfifo_fast_peek(struct Qdisc *qdisc) |
99c0db26 | 644 | { |
fd3ae5e8 KK |
645 | struct pfifo_fast_priv *priv = qdisc_priv(qdisc); |
646 | int band = bitmap2band[priv->bitmap]; | |
647 | ||
648 | if (band >= 0) { | |
48da34b7 | 649 | struct qdisc_skb_head *qh = band2list(priv, band); |
99c0db26 | 650 | |
48da34b7 | 651 | return qh->head; |
99c0db26 JP |
652 | } |
653 | ||
654 | return NULL; | |
655 | } | |
656 | ||
cc7ec456 | 657 | static void pfifo_fast_reset(struct Qdisc *qdisc) |
1da177e4 | 658 | { |
d3678b46 | 659 | int prio; |
fd3ae5e8 | 660 | struct pfifo_fast_priv *priv = qdisc_priv(qdisc); |
d3678b46 DM |
661 | |
662 | for (prio = 0; prio < PFIFO_FAST_BANDS; prio++) | |
1b5c5493 | 663 | __qdisc_reset_queue(band2list(priv, prio)); |
d3678b46 | 664 | |
fd3ae5e8 | 665 | priv->bitmap = 0; |
821d24ae | 666 | qdisc->qstats.backlog = 0; |
d3678b46 | 667 | qdisc->q.qlen = 0; |
1da177e4 LT |
668 | } |
669 | ||
d3678b46 DM |
670 | static int pfifo_fast_dump(struct Qdisc *qdisc, struct sk_buff *skb) |
671 | { | |
672 | struct tc_prio_qopt opt = { .bands = PFIFO_FAST_BANDS }; | |
673 | ||
cc7ec456 | 674 | memcpy(&opt.priomap, prio2band, TC_PRIO_MAX + 1); |
1b34ec43 DM |
675 | if (nla_put(skb, TCA_OPTIONS, sizeof(opt), &opt)) |
676 | goto nla_put_failure; | |
d3678b46 DM |
677 | return skb->len; |
678 | ||
679 | nla_put_failure: | |
680 | return -1; | |
681 | } | |
682 | ||
683 | static int pfifo_fast_init(struct Qdisc *qdisc, struct nlattr *opt) | |
684 | { | |
685 | int prio; | |
fd3ae5e8 | 686 | struct pfifo_fast_priv *priv = qdisc_priv(qdisc); |
d3678b46 DM |
687 | |
688 | for (prio = 0; prio < PFIFO_FAST_BANDS; prio++) | |
48da34b7 | 689 | qdisc_skb_head_init(band2list(priv, prio)); |
d3678b46 | 690 | |
23624935 ED |
691 | /* Can by-pass the queue discipline */ |
692 | qdisc->flags |= TCQ_F_CAN_BYPASS; | |
d3678b46 DM |
693 | return 0; |
694 | } | |
695 | ||
6ec1c69a | 696 | struct Qdisc_ops pfifo_fast_ops __read_mostly = { |
d3678b46 | 697 | .id = "pfifo_fast", |
fd3ae5e8 | 698 | .priv_size = sizeof(struct pfifo_fast_priv), |
d3678b46 DM |
699 | .enqueue = pfifo_fast_enqueue, |
700 | .dequeue = pfifo_fast_dequeue, | |
99c0db26 | 701 | .peek = pfifo_fast_peek, |
d3678b46 DM |
702 | .init = pfifo_fast_init, |
703 | .reset = pfifo_fast_reset, | |
704 | .dump = pfifo_fast_dump, | |
1da177e4 LT |
705 | .owner = THIS_MODULE, |
706 | }; | |
1f27cde3 | 707 | EXPORT_SYMBOL(pfifo_fast_ops); |
1da177e4 | 708 | |
23d3b8bf | 709 | static struct lock_class_key qdisc_tx_busylock; |
f9eb8aea | 710 | static struct lock_class_key qdisc_running_key; |
23d3b8bf | 711 | |
5ce2d488 | 712 | struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue, |
d2a7f269 | 713 | const struct Qdisc_ops *ops) |
1da177e4 LT |
714 | { |
715 | void *p; | |
716 | struct Qdisc *sch; | |
d276055c | 717 | unsigned int size = QDISC_ALIGN(sizeof(*sch)) + ops->priv_size; |
3d54b82f | 718 | int err = -ENOBUFS; |
26aa0459 JSP |
719 | struct net_device *dev; |
720 | ||
721 | if (!dev_queue) { | |
722 | err = -EINVAL; | |
723 | goto errout; | |
724 | } | |
1da177e4 | 725 | |
26aa0459 | 726 | dev = dev_queue->dev; |
f2cd2d3e ED |
727 | p = kzalloc_node(size, GFP_KERNEL, |
728 | netdev_queue_numa_node_read(dev_queue)); | |
729 | ||
1da177e4 | 730 | if (!p) |
3d54b82f | 731 | goto errout; |
3d54b82f | 732 | sch = (struct Qdisc *) QDISC_ALIGN((unsigned long) p); |
d276055c ED |
733 | /* if we got non aligned memory, ask more and do alignment ourself */ |
734 | if (sch != p) { | |
735 | kfree(p); | |
736 | p = kzalloc_node(size + QDISC_ALIGNTO - 1, GFP_KERNEL, | |
737 | netdev_queue_numa_node_read(dev_queue)); | |
738 | if (!p) | |
739 | goto errout; | |
740 | sch = (struct Qdisc *) QDISC_ALIGN((unsigned long) p); | |
741 | sch->padded = (char *) sch - (char *) p; | |
742 | } | |
a53851e2 | 743 | __skb_queue_head_init(&sch->gso_skb); |
70e57d5e | 744 | __skb_queue_head_init(&sch->skb_bad_txq); |
48da34b7 FW |
745 | qdisc_skb_head_init(&sch->q); |
746 | spin_lock_init(&sch->q.lock); | |
23d3b8bf | 747 | |
d59f5ffa JF |
748 | if (ops->static_flags & TCQ_F_CPUSTATS) { |
749 | sch->cpu_bstats = | |
750 | netdev_alloc_pcpu_stats(struct gnet_stats_basic_cpu); | |
751 | if (!sch->cpu_bstats) | |
752 | goto errout1; | |
753 | ||
754 | sch->cpu_qstats = alloc_percpu(struct gnet_stats_queue); | |
755 | if (!sch->cpu_qstats) { | |
756 | free_percpu(sch->cpu_bstats); | |
757 | goto errout1; | |
758 | } | |
759 | } | |
760 | ||
79640a4c | 761 | spin_lock_init(&sch->busylock); |
23d3b8bf ED |
762 | lockdep_set_class(&sch->busylock, |
763 | dev->qdisc_tx_busylock ?: &qdisc_tx_busylock); | |
764 | ||
f9eb8aea ED |
765 | seqcount_init(&sch->running); |
766 | lockdep_set_class(&sch->running, | |
767 | dev->qdisc_running_key ?: &qdisc_running_key); | |
768 | ||
1da177e4 | 769 | sch->ops = ops; |
d59f5ffa | 770 | sch->flags = ops->static_flags; |
1da177e4 LT |
771 | sch->enqueue = ops->enqueue; |
772 | sch->dequeue = ops->dequeue; | |
bb949fbd | 773 | sch->dev_queue = dev_queue; |
23d3b8bf | 774 | dev_hold(dev); |
7b936405 | 775 | refcount_set(&sch->refcnt, 1); |
3d54b82f TG |
776 | |
777 | return sch; | |
d59f5ffa JF |
778 | errout1: |
779 | kfree(p); | |
3d54b82f | 780 | errout: |
01e123d7 | 781 | return ERR_PTR(err); |
3d54b82f TG |
782 | } |
783 | ||
3511c913 | 784 | struct Qdisc *qdisc_create_dflt(struct netdev_queue *dev_queue, |
d2a7f269 | 785 | const struct Qdisc_ops *ops, |
786 | unsigned int parentid) | |
3d54b82f TG |
787 | { |
788 | struct Qdisc *sch; | |
10297b99 | 789 | |
6da7c8fc | 790 | if (!try_module_get(ops->owner)) |
166ee5b8 | 791 | return NULL; |
6da7c8fc | 792 | |
5ce2d488 | 793 | sch = qdisc_alloc(dev_queue, ops); |
166ee5b8 ED |
794 | if (IS_ERR(sch)) { |
795 | module_put(ops->owner); | |
796 | return NULL; | |
797 | } | |
9f9afec4 | 798 | sch->parent = parentid; |
3d54b82f | 799 | |
1da177e4 LT |
800 | if (!ops->init || ops->init(sch, NULL) == 0) |
801 | return sch; | |
802 | ||
0fbbeb1b | 803 | qdisc_destroy(sch); |
1da177e4 LT |
804 | return NULL; |
805 | } | |
62e3ba1b | 806 | EXPORT_SYMBOL(qdisc_create_dflt); |
1da177e4 | 807 | |
5fb66229 | 808 | /* Under qdisc_lock(qdisc) and BH! */ |
1da177e4 LT |
809 | |
810 | void qdisc_reset(struct Qdisc *qdisc) | |
811 | { | |
20fea08b | 812 | const struct Qdisc_ops *ops = qdisc->ops; |
a53851e2 | 813 | struct sk_buff *skb, *tmp; |
1da177e4 LT |
814 | |
815 | if (ops->reset) | |
816 | ops->reset(qdisc); | |
67305ebc | 817 | |
a53851e2 JF |
818 | skb_queue_walk_safe(&qdisc->gso_skb, skb, tmp) { |
819 | __skb_unlink(skb, &qdisc->gso_skb); | |
820 | kfree_skb_list(skb); | |
bbd8a0d3 | 821 | } |
a53851e2 | 822 | |
70e57d5e JF |
823 | skb_queue_walk_safe(&qdisc->skb_bad_txq, skb, tmp) { |
824 | __skb_unlink(skb, &qdisc->skb_bad_txq); | |
825 | kfree_skb_list(skb); | |
826 | } | |
827 | ||
4d202a0d | 828 | qdisc->q.qlen = 0; |
c8e18129 | 829 | qdisc->qstats.backlog = 0; |
1da177e4 | 830 | } |
62e3ba1b | 831 | EXPORT_SYMBOL(qdisc_reset); |
1da177e4 | 832 | |
752fbcc3 | 833 | static void qdisc_free(struct Qdisc *qdisc) |
5d944c64 | 834 | { |
73c20a8b | 835 | if (qdisc_is_percpu_stats(qdisc)) { |
22e0f8b9 | 836 | free_percpu(qdisc->cpu_bstats); |
73c20a8b JF |
837 | free_percpu(qdisc->cpu_qstats); |
838 | } | |
22e0f8b9 | 839 | |
5d944c64 ED |
840 | kfree((char *) qdisc - qdisc->padded); |
841 | } | |
842 | ||
1e0d5a57 | 843 | void qdisc_destroy(struct Qdisc *qdisc) |
1da177e4 | 844 | { |
8a34c5dc | 845 | const struct Qdisc_ops *ops = qdisc->ops; |
a53851e2 | 846 | struct sk_buff *skb, *tmp; |
8a34c5dc | 847 | |
1e0d5a57 | 848 | if (qdisc->flags & TCQ_F_BUILTIN || |
7b936405 | 849 | !refcount_dec_and_test(&qdisc->refcnt)) |
1e0d5a57 DM |
850 | return; |
851 | ||
3a682fbd | 852 | #ifdef CONFIG_NET_SCHED |
59cc1f61 | 853 | qdisc_hash_del(qdisc); |
f6e0b239 | 854 | |
a2da570d | 855 | qdisc_put_stab(rtnl_dereference(qdisc->stab)); |
3a682fbd | 856 | #endif |
1c0d32fd | 857 | gen_kill_estimator(&qdisc->rate_est); |
8a34c5dc DM |
858 | if (ops->reset) |
859 | ops->reset(qdisc); | |
860 | if (ops->destroy) | |
861 | ops->destroy(qdisc); | |
862 | ||
863 | module_put(ops->owner); | |
864 | dev_put(qdisc_dev(qdisc)); | |
865 | ||
a53851e2 JF |
866 | skb_queue_walk_safe(&qdisc->gso_skb, skb, tmp) { |
867 | __skb_unlink(skb, &qdisc->gso_skb); | |
868 | kfree_skb_list(skb); | |
869 | } | |
870 | ||
70e57d5e JF |
871 | skb_queue_walk_safe(&qdisc->skb_bad_txq, skb, tmp) { |
872 | __skb_unlink(skb, &qdisc->skb_bad_txq); | |
873 | kfree_skb_list(skb); | |
874 | } | |
875 | ||
752fbcc3 | 876 | qdisc_free(qdisc); |
1da177e4 | 877 | } |
62e3ba1b | 878 | EXPORT_SYMBOL(qdisc_destroy); |
1da177e4 | 879 | |
589983cd PM |
880 | /* Attach toplevel qdisc to device queue. */ |
881 | struct Qdisc *dev_graft_qdisc(struct netdev_queue *dev_queue, | |
882 | struct Qdisc *qdisc) | |
883 | { | |
884 | struct Qdisc *oqdisc = dev_queue->qdisc_sleeping; | |
885 | spinlock_t *root_lock; | |
886 | ||
887 | root_lock = qdisc_lock(oqdisc); | |
888 | spin_lock_bh(root_lock); | |
889 | ||
589983cd PM |
890 | /* ... and graft new one */ |
891 | if (qdisc == NULL) | |
892 | qdisc = &noop_qdisc; | |
893 | dev_queue->qdisc_sleeping = qdisc; | |
894 | rcu_assign_pointer(dev_queue->qdisc, &noop_qdisc); | |
895 | ||
896 | spin_unlock_bh(root_lock); | |
897 | ||
898 | return oqdisc; | |
899 | } | |
b8970f0b | 900 | EXPORT_SYMBOL(dev_graft_qdisc); |
589983cd | 901 | |
e8a0464c DM |
902 | static void attach_one_default_qdisc(struct net_device *dev, |
903 | struct netdev_queue *dev_queue, | |
904 | void *_unused) | |
905 | { | |
3e692f21 PS |
906 | struct Qdisc *qdisc; |
907 | const struct Qdisc_ops *ops = default_qdisc_ops; | |
e8a0464c | 908 | |
3e692f21 PS |
909 | if (dev->priv_flags & IFF_NO_QUEUE) |
910 | ops = &noqueue_qdisc_ops; | |
911 | ||
912 | qdisc = qdisc_create_dflt(dev_queue, ops, TC_H_ROOT); | |
913 | if (!qdisc) { | |
914 | netdev_info(dev, "activation failed\n"); | |
915 | return; | |
e8a0464c | 916 | } |
3e692f21 | 917 | if (!netif_is_multiqueue(dev)) |
4eaf3b84 | 918 | qdisc->flags |= TCQ_F_ONETXQUEUE | TCQ_F_NOPARENT; |
e8a0464c DM |
919 | dev_queue->qdisc_sleeping = qdisc; |
920 | } | |
921 | ||
6ec1c69a DM |
922 | static void attach_default_qdiscs(struct net_device *dev) |
923 | { | |
924 | struct netdev_queue *txq; | |
925 | struct Qdisc *qdisc; | |
926 | ||
927 | txq = netdev_get_tx_queue(dev, 0); | |
928 | ||
4b469955 | 929 | if (!netif_is_multiqueue(dev) || |
4b469955 | 930 | dev->priv_flags & IFF_NO_QUEUE) { |
6ec1c69a DM |
931 | netdev_for_each_tx_queue(dev, attach_one_default_qdisc, NULL); |
932 | dev->qdisc = txq->qdisc_sleeping; | |
551143d8 | 933 | qdisc_refcount_inc(dev->qdisc); |
6ec1c69a | 934 | } else { |
3511c913 | 935 | qdisc = qdisc_create_dflt(txq, &mq_qdisc_ops, TC_H_ROOT); |
6ec1c69a | 936 | if (qdisc) { |
6ec1c69a | 937 | dev->qdisc = qdisc; |
e57a784d | 938 | qdisc->ops->attach(qdisc); |
6ec1c69a DM |
939 | } |
940 | } | |
59cc1f61 | 941 | #ifdef CONFIG_NET_SCHED |
92f91706 | 942 | if (dev->qdisc != &noop_qdisc) |
49b49971 | 943 | qdisc_hash_add(dev->qdisc, false); |
59cc1f61 | 944 | #endif |
6ec1c69a DM |
945 | } |
946 | ||
e8a0464c DM |
947 | static void transition_one_qdisc(struct net_device *dev, |
948 | struct netdev_queue *dev_queue, | |
949 | void *_need_watchdog) | |
950 | { | |
83874000 | 951 | struct Qdisc *new_qdisc = dev_queue->qdisc_sleeping; |
e8a0464c DM |
952 | int *need_watchdog_p = _need_watchdog; |
953 | ||
a9312ae8 DM |
954 | if (!(new_qdisc->flags & TCQ_F_BUILTIN)) |
955 | clear_bit(__QDISC_STATE_DEACTIVATED, &new_qdisc->state); | |
956 | ||
83874000 | 957 | rcu_assign_pointer(dev_queue->qdisc, new_qdisc); |
3e692f21 | 958 | if (need_watchdog_p) { |
9d21493b | 959 | dev_queue->trans_start = 0; |
e8a0464c | 960 | *need_watchdog_p = 1; |
9d21493b | 961 | } |
e8a0464c DM |
962 | } |
963 | ||
1da177e4 LT |
964 | void dev_activate(struct net_device *dev) |
965 | { | |
e8a0464c | 966 | int need_watchdog; |
b0e1e646 | 967 | |
1da177e4 | 968 | /* No queueing discipline is attached to device; |
6da7c8fc | 969 | * create default one for devices, which need queueing |
970 | * and noqueue_qdisc for virtual interfaces | |
1da177e4 LT |
971 | */ |
972 | ||
6ec1c69a DM |
973 | if (dev->qdisc == &noop_qdisc) |
974 | attach_default_qdiscs(dev); | |
af356afa | 975 | |
cacaddf5 TC |
976 | if (!netif_carrier_ok(dev)) |
977 | /* Delay activation until next carrier-on event */ | |
978 | return; | |
979 | ||
e8a0464c DM |
980 | need_watchdog = 0; |
981 | netdev_for_each_tx_queue(dev, transition_one_qdisc, &need_watchdog); | |
24824a09 ED |
982 | if (dev_ingress_queue(dev)) |
983 | transition_one_qdisc(dev, dev_ingress_queue(dev), NULL); | |
e8a0464c DM |
984 | |
985 | if (need_watchdog) { | |
860e9538 | 986 | netif_trans_update(dev); |
1da177e4 LT |
987 | dev_watchdog_up(dev); |
988 | } | |
b0e1e646 | 989 | } |
b8970f0b | 990 | EXPORT_SYMBOL(dev_activate); |
b0e1e646 | 991 | |
e8a0464c DM |
992 | static void dev_deactivate_queue(struct net_device *dev, |
993 | struct netdev_queue *dev_queue, | |
994 | void *_qdisc_default) | |
b0e1e646 | 995 | { |
e8a0464c | 996 | struct Qdisc *qdisc_default = _qdisc_default; |
970565bb | 997 | struct Qdisc *qdisc; |
970565bb | 998 | |
46e5da40 | 999 | qdisc = rtnl_dereference(dev_queue->qdisc); |
b0e1e646 | 1000 | if (qdisc) { |
83874000 DM |
1001 | spin_lock_bh(qdisc_lock(qdisc)); |
1002 | ||
a9312ae8 DM |
1003 | if (!(qdisc->flags & TCQ_F_BUILTIN)) |
1004 | set_bit(__QDISC_STATE_DEACTIVATED, &qdisc->state); | |
1005 | ||
f7a54c13 | 1006 | rcu_assign_pointer(dev_queue->qdisc, qdisc_default); |
b0e1e646 | 1007 | qdisc_reset(qdisc); |
d3b753db | 1008 | |
83874000 | 1009 | spin_unlock_bh(qdisc_lock(qdisc)); |
b0e1e646 | 1010 | } |
1da177e4 LT |
1011 | } |
1012 | ||
4335cd2d | 1013 | static bool some_qdisc_is_busy(struct net_device *dev) |
e8a0464c DM |
1014 | { |
1015 | unsigned int i; | |
1016 | ||
1017 | for (i = 0; i < dev->num_tx_queues; i++) { | |
1018 | struct netdev_queue *dev_queue; | |
7698b4fc | 1019 | spinlock_t *root_lock; |
e2627c8c | 1020 | struct Qdisc *q; |
e8a0464c DM |
1021 | int val; |
1022 | ||
1023 | dev_queue = netdev_get_tx_queue(dev, i); | |
b9a3b110 | 1024 | q = dev_queue->qdisc_sleeping; |
e8a0464c | 1025 | |
6b3ba914 JF |
1026 | if (q->flags & TCQ_F_NOLOCK) { |
1027 | val = test_bit(__QDISC_STATE_SCHED, &q->state); | |
1028 | } else { | |
1029 | root_lock = qdisc_lock(q); | |
1030 | spin_lock_bh(root_lock); | |
e8a0464c | 1031 | |
6b3ba914 JF |
1032 | val = (qdisc_is_running(q) || |
1033 | test_bit(__QDISC_STATE_SCHED, &q->state)); | |
e8a0464c | 1034 | |
6b3ba914 JF |
1035 | spin_unlock_bh(root_lock); |
1036 | } | |
e8a0464c DM |
1037 | |
1038 | if (val) | |
1039 | return true; | |
1040 | } | |
1041 | return false; | |
1042 | } | |
1043 | ||
7bbde83b JF |
1044 | static void dev_qdisc_reset(struct net_device *dev, |
1045 | struct netdev_queue *dev_queue, | |
1046 | void *none) | |
1047 | { | |
1048 | struct Qdisc *qdisc = dev_queue->qdisc_sleeping; | |
1049 | ||
1050 | if (qdisc) | |
1051 | qdisc_reset(qdisc); | |
1052 | } | |
1053 | ||
3137663d ED |
1054 | /** |
1055 | * dev_deactivate_many - deactivate transmissions on several devices | |
1056 | * @head: list of devices to deactivate | |
1057 | * | |
1058 | * This function returns only when all outstanding transmissions | |
1059 | * have completed, unless all devices are in dismantle phase. | |
1060 | */ | |
44345724 | 1061 | void dev_deactivate_many(struct list_head *head) |
1da177e4 | 1062 | { |
44345724 | 1063 | struct net_device *dev; |
41a23b07 | 1064 | |
5cde2829 | 1065 | list_for_each_entry(dev, head, close_list) { |
44345724 OP |
1066 | netdev_for_each_tx_queue(dev, dev_deactivate_queue, |
1067 | &noop_qdisc); | |
1068 | if (dev_ingress_queue(dev)) | |
1069 | dev_deactivate_queue(dev, dev_ingress_queue(dev), | |
1070 | &noop_qdisc); | |
1071 | ||
1072 | dev_watchdog_down(dev); | |
1073 | } | |
1da177e4 | 1074 | |
3137663d ED |
1075 | /* Wait for outstanding qdisc-less dev_queue_xmit calls. |
1076 | * This is avoided if all devices are in dismantle phase : | |
1077 | * Caller will call synchronize_net() for us | |
1078 | */ | |
7bbde83b | 1079 | synchronize_net(); |
1da177e4 | 1080 | |
d4828d85 | 1081 | /* Wait for outstanding qdisc_run calls. */ |
7bbde83b | 1082 | list_for_each_entry(dev, head, close_list) { |
44345724 OP |
1083 | while (some_qdisc_is_busy(dev)) |
1084 | yield(); | |
7bbde83b JF |
1085 | /* The new qdisc is assigned at this point so we can safely |
1086 | * unwind stale skb lists and qdisc statistics | |
1087 | */ | |
1088 | netdev_for_each_tx_queue(dev, dev_qdisc_reset, NULL); | |
1089 | if (dev_ingress_queue(dev)) | |
1090 | dev_qdisc_reset(dev, dev_ingress_queue(dev), NULL); | |
1091 | } | |
44345724 OP |
1092 | } |
1093 | ||
1094 | void dev_deactivate(struct net_device *dev) | |
1095 | { | |
1096 | LIST_HEAD(single); | |
1097 | ||
5cde2829 | 1098 | list_add(&dev->close_list, &single); |
44345724 | 1099 | dev_deactivate_many(&single); |
5f04d506 | 1100 | list_del(&single); |
1da177e4 | 1101 | } |
b8970f0b | 1102 | EXPORT_SYMBOL(dev_deactivate); |
1da177e4 | 1103 | |
b0e1e646 DM |
1104 | static void dev_init_scheduler_queue(struct net_device *dev, |
1105 | struct netdev_queue *dev_queue, | |
e8a0464c | 1106 | void *_qdisc) |
b0e1e646 | 1107 | { |
e8a0464c DM |
1108 | struct Qdisc *qdisc = _qdisc; |
1109 | ||
46e5da40 | 1110 | rcu_assign_pointer(dev_queue->qdisc, qdisc); |
b0e1e646 | 1111 | dev_queue->qdisc_sleeping = qdisc; |
a53851e2 | 1112 | __skb_queue_head_init(&qdisc->gso_skb); |
70e57d5e | 1113 | __skb_queue_head_init(&qdisc->skb_bad_txq); |
b0e1e646 DM |
1114 | } |
1115 | ||
1da177e4 LT |
1116 | void dev_init_scheduler(struct net_device *dev) |
1117 | { | |
af356afa | 1118 | dev->qdisc = &noop_qdisc; |
e8a0464c | 1119 | netdev_for_each_tx_queue(dev, dev_init_scheduler_queue, &noop_qdisc); |
24824a09 ED |
1120 | if (dev_ingress_queue(dev)) |
1121 | dev_init_scheduler_queue(dev, dev_ingress_queue(dev), &noop_qdisc); | |
1da177e4 | 1122 | |
cdeabbb8 | 1123 | timer_setup(&dev->watchdog_timer, dev_watchdog, 0); |
1da177e4 LT |
1124 | } |
1125 | ||
e8a0464c DM |
1126 | static void shutdown_scheduler_queue(struct net_device *dev, |
1127 | struct netdev_queue *dev_queue, | |
1128 | void *_qdisc_default) | |
1da177e4 | 1129 | { |
b0e1e646 | 1130 | struct Qdisc *qdisc = dev_queue->qdisc_sleeping; |
e8a0464c | 1131 | struct Qdisc *qdisc_default = _qdisc_default; |
b0e1e646 DM |
1132 | |
1133 | if (qdisc) { | |
f7a54c13 | 1134 | rcu_assign_pointer(dev_queue->qdisc, qdisc_default); |
b0e1e646 | 1135 | dev_queue->qdisc_sleeping = qdisc_default; |
1da177e4 | 1136 | |
1da177e4 | 1137 | qdisc_destroy(qdisc); |
10297b99 | 1138 | } |
b0e1e646 DM |
1139 | } |
1140 | ||
1141 | void dev_shutdown(struct net_device *dev) | |
1142 | { | |
e8a0464c | 1143 | netdev_for_each_tx_queue(dev, shutdown_scheduler_queue, &noop_qdisc); |
24824a09 ED |
1144 | if (dev_ingress_queue(dev)) |
1145 | shutdown_scheduler_queue(dev, dev_ingress_queue(dev), &noop_qdisc); | |
af356afa PM |
1146 | qdisc_destroy(dev->qdisc); |
1147 | dev->qdisc = &noop_qdisc; | |
1148 | ||
547b792c | 1149 | WARN_ON(timer_pending(&dev->watchdog_timer)); |
1da177e4 | 1150 | } |
292f1c7f | 1151 | |
01cb71d2 | 1152 | void psched_ratecfg_precompute(struct psched_ratecfg *r, |
3e1e3aae ED |
1153 | const struct tc_ratespec *conf, |
1154 | u64 rate64) | |
292f1c7f | 1155 | { |
01cb71d2 ED |
1156 | memset(r, 0, sizeof(*r)); |
1157 | r->overhead = conf->overhead; | |
3e1e3aae | 1158 | r->rate_bytes_ps = max_t(u64, conf->rate, rate64); |
8a8e3d84 | 1159 | r->linklayer = (conf->linklayer & TC_LINKLAYER_MASK); |
292f1c7f JP |
1160 | r->mult = 1; |
1161 | /* | |
130d3d68 ED |
1162 | * The deal here is to replace a divide by a reciprocal one |
1163 | * in fast path (a reciprocal divide is a multiply and a shift) | |
1164 | * | |
1165 | * Normal formula would be : | |
1166 | * time_in_ns = (NSEC_PER_SEC * len) / rate_bps | |
1167 | * | |
1168 | * We compute mult/shift to use instead : | |
1169 | * time_in_ns = (len * mult) >> shift; | |
1170 | * | |
1171 | * We try to get the highest possible mult value for accuracy, | |
1172 | * but have to make sure no overflows will ever happen. | |
292f1c7f | 1173 | */ |
130d3d68 ED |
1174 | if (r->rate_bytes_ps > 0) { |
1175 | u64 factor = NSEC_PER_SEC; | |
1176 | ||
1177 | for (;;) { | |
1178 | r->mult = div64_u64(factor, r->rate_bytes_ps); | |
1179 | if (r->mult & (1U << 31) || factor & (1ULL << 63)) | |
292f1c7f | 1180 | break; |
130d3d68 ED |
1181 | factor <<= 1; |
1182 | r->shift++; | |
292f1c7f | 1183 | } |
292f1c7f JP |
1184 | } |
1185 | } | |
1186 | EXPORT_SYMBOL(psched_ratecfg_precompute); | |
46209401 JP |
1187 | |
1188 | static void mini_qdisc_rcu_func(struct rcu_head *head) | |
1189 | { | |
1190 | } | |
1191 | ||
1192 | void mini_qdisc_pair_swap(struct mini_Qdisc_pair *miniqp, | |
1193 | struct tcf_proto *tp_head) | |
1194 | { | |
1195 | struct mini_Qdisc *miniq_old = rtnl_dereference(*miniqp->p_miniq); | |
1196 | struct mini_Qdisc *miniq; | |
1197 | ||
1198 | if (!tp_head) { | |
1199 | RCU_INIT_POINTER(*miniqp->p_miniq, NULL); | |
1200 | return; | |
1201 | } | |
1202 | ||
1203 | miniq = !miniq_old || miniq_old == &miniqp->miniq2 ? | |
1204 | &miniqp->miniq1 : &miniqp->miniq2; | |
1205 | ||
1206 | /* We need to make sure that readers won't see the miniq | |
1207 | * we are about to modify. So wait until previous call_rcu_bh callback | |
1208 | * is done. | |
1209 | */ | |
1210 | rcu_barrier_bh(); | |
1211 | miniq->filter_list = tp_head; | |
1212 | rcu_assign_pointer(*miniqp->p_miniq, miniq); | |
1213 | ||
1214 | if (miniq_old) | |
1215 | /* This is counterpart of the rcu barrier above. We need to | |
1216 | * block potential new user of miniq_old until all readers | |
1217 | * are not seeing it. | |
1218 | */ | |
1219 | call_rcu_bh(&miniq_old->rcu, mini_qdisc_rcu_func); | |
1220 | } | |
1221 | EXPORT_SYMBOL(mini_qdisc_pair_swap); | |
1222 | ||
1223 | void mini_qdisc_pair_init(struct mini_Qdisc_pair *miniqp, struct Qdisc *qdisc, | |
1224 | struct mini_Qdisc __rcu **p_miniq) | |
1225 | { | |
1226 | miniqp->miniq1.cpu_bstats = qdisc->cpu_bstats; | |
1227 | miniqp->miniq1.cpu_qstats = qdisc->cpu_qstats; | |
1228 | miniqp->miniq2.cpu_bstats = qdisc->cpu_bstats; | |
1229 | miniqp->miniq2.cpu_qstats = qdisc->cpu_qstats; | |
1230 | miniqp->p_miniq = p_miniq; | |
1231 | } | |
1232 | EXPORT_SYMBOL(mini_qdisc_pair_init); |