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> |
c5ad119f | 29 | #include <linux/skb_array.h> |
32d3e51a | 30 | #include <linux/if_macvlan.h> |
292f1c7f | 31 | #include <net/sch_generic.h> |
1da177e4 | 32 | #include <net/pkt_sched.h> |
7fee226a | 33 | #include <net/dst.h> |
e543002f | 34 | #include <trace/events/qdisc.h> |
1da177e4 | 35 | |
34aedd3f | 36 | /* Qdisc to use by default */ |
37 | const struct Qdisc_ops *default_qdisc_ops = &pfifo_fast_ops; | |
38 | EXPORT_SYMBOL(default_qdisc_ops); | |
39 | ||
1da177e4 LT |
40 | /* Main transmission queue. */ |
41 | ||
0463d4ae | 42 | /* Modifications to data participating in scheduling must be protected with |
5fb66229 | 43 | * qdisc_lock(qdisc) spinlock. |
0463d4ae PM |
44 | * |
45 | * The idea is the following: | |
c7e4f3bb DM |
46 | * - enqueue, dequeue are serialized via qdisc root lock |
47 | * - ingress filtering is also serialized via qdisc root lock | |
0463d4ae | 48 | * - updates to tree and tree walking are only done under the rtnl mutex. |
1da177e4 | 49 | */ |
70e57d5e JF |
50 | |
51 | static inline struct sk_buff *__skb_dequeue_bad_txq(struct Qdisc *q) | |
52 | { | |
53 | const struct netdev_queue *txq = q->dev_queue; | |
54 | spinlock_t *lock = NULL; | |
55 | struct sk_buff *skb; | |
56 | ||
57 | if (q->flags & TCQ_F_NOLOCK) { | |
58 | lock = qdisc_lock(q); | |
59 | spin_lock(lock); | |
60 | } | |
61 | ||
62 | skb = skb_peek(&q->skb_bad_txq); | |
63 | if (skb) { | |
64 | /* check the reason of requeuing without tx lock first */ | |
65 | txq = skb_get_tx_queue(txq->dev, skb); | |
66 | if (!netif_xmit_frozen_or_stopped(txq)) { | |
67 | skb = __skb_dequeue(&q->skb_bad_txq); | |
68 | if (qdisc_is_percpu_stats(q)) { | |
69 | qdisc_qstats_cpu_backlog_dec(q, skb); | |
70 | qdisc_qstats_cpu_qlen_dec(q); | |
71 | } else { | |
72 | qdisc_qstats_backlog_dec(q, skb); | |
73 | q->q.qlen--; | |
74 | } | |
75 | } else { | |
76 | skb = NULL; | |
77 | } | |
78 | } | |
79 | ||
80 | if (lock) | |
81 | spin_unlock(lock); | |
82 | ||
83 | return skb; | |
84 | } | |
85 | ||
86 | static inline struct sk_buff *qdisc_dequeue_skb_bad_txq(struct Qdisc *q) | |
87 | { | |
88 | struct sk_buff *skb = skb_peek(&q->skb_bad_txq); | |
89 | ||
90 | if (unlikely(skb)) | |
91 | skb = __skb_dequeue_bad_txq(q); | |
92 | ||
93 | return skb; | |
94 | } | |
95 | ||
96 | static inline void qdisc_enqueue_skb_bad_txq(struct Qdisc *q, | |
97 | struct sk_buff *skb) | |
98 | { | |
99 | spinlock_t *lock = NULL; | |
100 | ||
101 | if (q->flags & TCQ_F_NOLOCK) { | |
102 | lock = qdisc_lock(q); | |
103 | spin_lock(lock); | |
104 | } | |
105 | ||
106 | __skb_queue_tail(&q->skb_bad_txq, skb); | |
107 | ||
108 | if (lock) | |
109 | spin_unlock(lock); | |
110 | } | |
111 | ||
a53851e2 | 112 | static inline int __dev_requeue_skb(struct sk_buff *skb, struct Qdisc *q) |
c716a81a | 113 | { |
a53851e2 | 114 | __skb_queue_head(&q->gso_skb, skb); |
53e91503 | 115 | q->qstats.requeues++; |
a27758ff | 116 | qdisc_qstats_backlog_inc(q, skb); |
bbd8a0d3 | 117 | q->q.qlen++; /* it's still part of the queue */ |
37437bb2 | 118 | __netif_schedule(q); |
6252352d | 119 | |
c716a81a JHS |
120 | return 0; |
121 | } | |
122 | ||
a53851e2 JF |
123 | static inline int dev_requeue_skb_locked(struct sk_buff *skb, struct Qdisc *q) |
124 | { | |
125 | spinlock_t *lock = qdisc_lock(q); | |
126 | ||
127 | spin_lock(lock); | |
128 | __skb_queue_tail(&q->gso_skb, skb); | |
129 | spin_unlock(lock); | |
130 | ||
131 | qdisc_qstats_cpu_requeues_inc(q); | |
132 | qdisc_qstats_cpu_backlog_inc(q, skb); | |
133 | qdisc_qstats_cpu_qlen_inc(q); | |
134 | __netif_schedule(q); | |
135 | ||
136 | return 0; | |
137 | } | |
138 | ||
139 | static inline int dev_requeue_skb(struct sk_buff *skb, struct Qdisc *q) | |
140 | { | |
141 | if (q->flags & TCQ_F_NOLOCK) | |
142 | return dev_requeue_skb_locked(skb, q); | |
143 | else | |
144 | return __dev_requeue_skb(skb, q); | |
145 | } | |
146 | ||
55a93b3e ED |
147 | static void try_bulk_dequeue_skb(struct Qdisc *q, |
148 | struct sk_buff *skb, | |
b8358d70 JDB |
149 | const struct netdev_queue *txq, |
150 | int *packets) | |
5772e9a3 | 151 | { |
55a93b3e | 152 | int bytelimit = qdisc_avail_bulklimit(txq) - skb->len; |
5772e9a3 JDB |
153 | |
154 | while (bytelimit > 0) { | |
55a93b3e | 155 | struct sk_buff *nskb = q->dequeue(q); |
5772e9a3 | 156 | |
55a93b3e | 157 | if (!nskb) |
5772e9a3 JDB |
158 | break; |
159 | ||
55a93b3e ED |
160 | bytelimit -= nskb->len; /* covers GSO len */ |
161 | skb->next = nskb; | |
162 | skb = nskb; | |
b8358d70 | 163 | (*packets)++; /* GSO counts as one pkt */ |
5772e9a3 | 164 | } |
55a93b3e | 165 | skb->next = NULL; |
5772e9a3 JDB |
166 | } |
167 | ||
4d202a0d ED |
168 | /* This variant of try_bulk_dequeue_skb() makes sure |
169 | * all skbs in the chain are for the same txq | |
170 | */ | |
171 | static void try_bulk_dequeue_skb_slow(struct Qdisc *q, | |
172 | struct sk_buff *skb, | |
173 | int *packets) | |
174 | { | |
175 | int mapping = skb_get_queue_mapping(skb); | |
176 | struct sk_buff *nskb; | |
177 | int cnt = 0; | |
178 | ||
179 | do { | |
180 | nskb = q->dequeue(q); | |
181 | if (!nskb) | |
182 | break; | |
183 | if (unlikely(skb_get_queue_mapping(nskb) != mapping)) { | |
70e57d5e JF |
184 | qdisc_enqueue_skb_bad_txq(q, nskb); |
185 | ||
186 | if (qdisc_is_percpu_stats(q)) { | |
187 | qdisc_qstats_cpu_backlog_inc(q, nskb); | |
188 | qdisc_qstats_cpu_qlen_inc(q); | |
189 | } else { | |
190 | qdisc_qstats_backlog_inc(q, nskb); | |
191 | q->q.qlen++; | |
192 | } | |
4d202a0d ED |
193 | break; |
194 | } | |
195 | skb->next = nskb; | |
196 | skb = nskb; | |
197 | } while (++cnt < 8); | |
198 | (*packets) += cnt; | |
199 | skb->next = NULL; | |
200 | } | |
201 | ||
5772e9a3 JDB |
202 | /* Note that dequeue_skb can possibly return a SKB list (via skb->next). |
203 | * A requeued skb (via q->gso_skb) can also be a SKB list. | |
204 | */ | |
b8358d70 JDB |
205 | static struct sk_buff *dequeue_skb(struct Qdisc *q, bool *validate, |
206 | int *packets) | |
c716a81a | 207 | { |
1abbe139 | 208 | const struct netdev_queue *txq = q->dev_queue; |
fd8e8d1a | 209 | struct sk_buff *skb = NULL; |
554794de | 210 | |
b8358d70 | 211 | *packets = 1; |
a53851e2 JF |
212 | if (unlikely(!skb_queue_empty(&q->gso_skb))) { |
213 | spinlock_t *lock = NULL; | |
214 | ||
215 | if (q->flags & TCQ_F_NOLOCK) { | |
216 | lock = qdisc_lock(q); | |
217 | spin_lock(lock); | |
218 | } | |
219 | ||
220 | skb = skb_peek(&q->gso_skb); | |
221 | ||
222 | /* skb may be null if another cpu pulls gso_skb off in between | |
223 | * empty check and lock. | |
224 | */ | |
225 | if (!skb) { | |
226 | if (lock) | |
227 | spin_unlock(lock); | |
228 | goto validate; | |
229 | } | |
230 | ||
4d202a0d ED |
231 | /* skb in gso_skb were already validated */ |
232 | *validate = false; | |
ebf05982 | 233 | /* check the reason of requeuing without tx lock first */ |
10c51b56 | 234 | txq = skb_get_tx_queue(txq->dev, skb); |
73466498 | 235 | if (!netif_xmit_frozen_or_stopped(txq)) { |
a53851e2 JF |
236 | skb = __skb_dequeue(&q->gso_skb); |
237 | if (qdisc_is_percpu_stats(q)) { | |
238 | qdisc_qstats_cpu_backlog_dec(q, skb); | |
239 | qdisc_qstats_cpu_qlen_dec(q); | |
240 | } else { | |
241 | qdisc_qstats_backlog_dec(q, skb); | |
242 | q->q.qlen--; | |
243 | } | |
244 | } else { | |
ebf05982 | 245 | skb = NULL; |
a53851e2 JF |
246 | } |
247 | if (lock) | |
248 | spin_unlock(lock); | |
e543002f | 249 | goto trace; |
4d202a0d | 250 | } |
a53851e2 | 251 | validate: |
4d202a0d | 252 | *validate = true; |
fd8e8d1a JF |
253 | |
254 | if ((q->flags & TCQ_F_ONETXQUEUE) && | |
255 | netif_xmit_frozen_or_stopped(txq)) | |
256 | return skb; | |
257 | ||
70e57d5e JF |
258 | skb = qdisc_dequeue_skb_bad_txq(q); |
259 | if (unlikely(skb)) | |
260 | goto bulk; | |
fd8e8d1a | 261 | skb = q->dequeue(q); |
4d202a0d ED |
262 | if (skb) { |
263 | bulk: | |
264 | if (qdisc_may_bulk(q)) | |
265 | try_bulk_dequeue_skb(q, skb, txq, packets); | |
266 | else | |
267 | try_bulk_dequeue_skb_slow(q, skb, packets); | |
ebf05982 | 268 | } |
e543002f JDB |
269 | trace: |
270 | trace_qdisc_dequeue(q, txq, *packets, skb); | |
c716a81a JHS |
271 | return skb; |
272 | } | |
273 | ||
10297b99 | 274 | /* |
10770bc2 | 275 | * Transmit possibly several skbs, and handle the return status as |
f9eb8aea | 276 | * required. Owning running seqcount bit guarantees that |
10770bc2 | 277 | * only one CPU can execute this function. |
6c1361a6 KK |
278 | * |
279 | * Returns to the caller: | |
29b86cda JF |
280 | * false - hardware queue frozen backoff |
281 | * true - feel free to send more pkts | |
6c1361a6 | 282 | */ |
29b86cda JF |
283 | bool sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q, |
284 | struct net_device *dev, struct netdev_queue *txq, | |
285 | spinlock_t *root_lock, bool validate) | |
1da177e4 | 286 | { |
5f1a485d | 287 | int ret = NETDEV_TX_BUSY; |
7698b4fc DM |
288 | |
289 | /* And release qdisc */ | |
6b3ba914 JF |
290 | if (root_lock) |
291 | spin_unlock(root_lock); | |
c716a81a | 292 | |
55a93b3e ED |
293 | /* Note that we validate skb (GSO, checksum, ...) outside of locks */ |
294 | if (validate) | |
295 | skb = validate_xmit_skb_list(skb, dev); | |
572a9d7b | 296 | |
3dcd493f | 297 | if (likely(skb)) { |
55a93b3e ED |
298 | HARD_TX_LOCK(dev, txq, smp_processor_id()); |
299 | if (!netif_xmit_frozen_or_stopped(txq)) | |
300 | skb = dev_hard_start_xmit(skb, dev, txq, &ret); | |
c716a81a | 301 | |
55a93b3e | 302 | HARD_TX_UNLOCK(dev, txq); |
3dcd493f | 303 | } else { |
6b3ba914 JF |
304 | if (root_lock) |
305 | spin_lock(root_lock); | |
29b86cda | 306 | return true; |
55a93b3e | 307 | } |
6b3ba914 JF |
308 | |
309 | if (root_lock) | |
310 | spin_lock(root_lock); | |
c716a81a | 311 | |
29b86cda | 312 | if (!dev_xmit_complete(ret)) { |
6c1361a6 | 313 | /* Driver returned NETDEV_TX_BUSY - requeue skb */ |
e87cc472 JP |
314 | if (unlikely(ret != NETDEV_TX_BUSY)) |
315 | net_warn_ratelimited("BUG %s code %d qlen %d\n", | |
316 | dev->name, ret, q->q.qlen); | |
6c1361a6 | 317 | |
29b86cda JF |
318 | dev_requeue_skb(skb, q); |
319 | return false; | |
6c1361a6 | 320 | } |
c716a81a | 321 | |
73466498 | 322 | if (ret && netif_xmit_frozen_or_stopped(txq)) |
29b86cda | 323 | return false; |
37437bb2 | 324 | |
29b86cda | 325 | return true; |
1da177e4 LT |
326 | } |
327 | ||
bbd8a0d3 KK |
328 | /* |
329 | * NOTE: Called under qdisc_lock(q) with locally disabled BH. | |
330 | * | |
f9eb8aea | 331 | * running seqcount guarantees only one CPU can process |
bbd8a0d3 KK |
332 | * this qdisc at a time. qdisc_lock(q) serializes queue accesses for |
333 | * this queue. | |
334 | * | |
335 | * netif_tx_lock serializes accesses to device driver. | |
336 | * | |
337 | * qdisc_lock(q) and netif_tx_lock are mutually exclusive, | |
338 | * if one is grabbed, another must be free. | |
339 | * | |
340 | * Note, that this procedure can be called by a watchdog timer | |
341 | * | |
342 | * Returns to the caller: | |
343 | * 0 - queue is empty or throttled. | |
344 | * >0 - queue is not empty. | |
345 | * | |
346 | */ | |
29b86cda | 347 | static inline bool qdisc_restart(struct Qdisc *q, int *packets) |
bbd8a0d3 | 348 | { |
6b3ba914 | 349 | spinlock_t *root_lock = NULL; |
bbd8a0d3 KK |
350 | struct netdev_queue *txq; |
351 | struct net_device *dev; | |
bbd8a0d3 | 352 | struct sk_buff *skb; |
55a93b3e | 353 | bool validate; |
bbd8a0d3 KK |
354 | |
355 | /* Dequeue packet */ | |
b8358d70 | 356 | skb = dequeue_skb(q, &validate, packets); |
bbd8a0d3 | 357 | if (unlikely(!skb)) |
29b86cda | 358 | return false; |
10c51b56 | 359 | |
6b3ba914 JF |
360 | if (!(q->flags & TCQ_F_NOLOCK)) |
361 | root_lock = qdisc_lock(q); | |
362 | ||
bbd8a0d3 | 363 | dev = qdisc_dev(q); |
10c51b56 | 364 | txq = skb_get_tx_queue(dev, skb); |
bbd8a0d3 | 365 | |
55a93b3e | 366 | return sch_direct_xmit(skb, q, dev, txq, root_lock, validate); |
bbd8a0d3 KK |
367 | } |
368 | ||
37437bb2 | 369 | void __qdisc_run(struct Qdisc *q) |
48d83325 | 370 | { |
3d48b53f | 371 | int quota = dev_tx_weight; |
b8358d70 | 372 | int packets; |
2ba2506c | 373 | |
b8358d70 | 374 | while (qdisc_restart(q, &packets)) { |
2ba2506c | 375 | /* |
d5b8aa1d | 376 | * Ordered by possible occurrence: Postpone processing if |
377 | * 1. we've exceeded packet quota | |
378 | * 2. another process needs the CPU; | |
2ba2506c | 379 | */ |
b8358d70 JDB |
380 | quota -= packets; |
381 | if (quota <= 0 || need_resched()) { | |
37437bb2 | 382 | __netif_schedule(q); |
d90df3ad | 383 | break; |
2ba2506c HX |
384 | } |
385 | } | |
48d83325 HX |
386 | } |
387 | ||
9d21493b ED |
388 | unsigned long dev_trans_start(struct net_device *dev) |
389 | { | |
07ce76aa | 390 | unsigned long val, res; |
9d21493b ED |
391 | unsigned int i; |
392 | ||
07ce76aa | 393 | if (is_vlan_dev(dev)) |
394 | dev = vlan_dev_real_dev(dev); | |
32d3e51a CD |
395 | else if (netif_is_macvlan(dev)) |
396 | dev = macvlan_dev_real_dev(dev); | |
9b36627a FW |
397 | res = netdev_get_tx_queue(dev, 0)->trans_start; |
398 | for (i = 1; i < dev->num_tx_queues; i++) { | |
9d21493b ED |
399 | val = netdev_get_tx_queue(dev, i)->trans_start; |
400 | if (val && time_after(val, res)) | |
401 | res = val; | |
402 | } | |
07ce76aa | 403 | |
9d21493b ED |
404 | return res; |
405 | } | |
406 | EXPORT_SYMBOL(dev_trans_start); | |
407 | ||
cdeabbb8 | 408 | static void dev_watchdog(struct timer_list *t) |
1da177e4 | 409 | { |
cdeabbb8 | 410 | struct net_device *dev = from_timer(dev, t, watchdog_timer); |
1da177e4 | 411 | |
932ff279 | 412 | netif_tx_lock(dev); |
e8a0464c | 413 | if (!qdisc_tx_is_noop(dev)) { |
1da177e4 LT |
414 | if (netif_device_present(dev) && |
415 | netif_running(dev) && | |
416 | netif_carrier_ok(dev)) { | |
9d21493b | 417 | int some_queue_timedout = 0; |
e8a0464c | 418 | unsigned int i; |
9d21493b | 419 | unsigned long trans_start; |
e8a0464c DM |
420 | |
421 | for (i = 0; i < dev->num_tx_queues; i++) { | |
422 | struct netdev_queue *txq; | |
423 | ||
424 | txq = netdev_get_tx_queue(dev, i); | |
9b36627a | 425 | trans_start = txq->trans_start; |
73466498 | 426 | if (netif_xmit_stopped(txq) && |
9d21493b ED |
427 | time_after(jiffies, (trans_start + |
428 | dev->watchdog_timeo))) { | |
429 | some_queue_timedout = 1; | |
ccf5ff69 | 430 | txq->trans_timeout++; |
e8a0464c DM |
431 | break; |
432 | } | |
433 | } | |
338f7566 | 434 | |
9d21493b | 435 | if (some_queue_timedout) { |
9d21493b | 436 | WARN_ONCE(1, KERN_INFO "NETDEV WATCHDOG: %s (%s): transmit queue %u timed out\n", |
3019de12 | 437 | dev->name, netdev_drivername(dev), i); |
d314774c | 438 | dev->netdev_ops->ndo_tx_timeout(dev); |
1da177e4 | 439 | } |
e8a0464c DM |
440 | if (!mod_timer(&dev->watchdog_timer, |
441 | round_jiffies(jiffies + | |
442 | dev->watchdog_timeo))) | |
1da177e4 LT |
443 | dev_hold(dev); |
444 | } | |
445 | } | |
932ff279 | 446 | netif_tx_unlock(dev); |
1da177e4 LT |
447 | |
448 | dev_put(dev); | |
449 | } | |
450 | ||
1da177e4 LT |
451 | void __netdev_watchdog_up(struct net_device *dev) |
452 | { | |
d314774c | 453 | if (dev->netdev_ops->ndo_tx_timeout) { |
1da177e4 LT |
454 | if (dev->watchdog_timeo <= 0) |
455 | dev->watchdog_timeo = 5*HZ; | |
60468d5b VP |
456 | if (!mod_timer(&dev->watchdog_timer, |
457 | round_jiffies(jiffies + dev->watchdog_timeo))) | |
1da177e4 LT |
458 | dev_hold(dev); |
459 | } | |
460 | } | |
461 | ||
462 | static void dev_watchdog_up(struct net_device *dev) | |
463 | { | |
1da177e4 | 464 | __netdev_watchdog_up(dev); |
1da177e4 LT |
465 | } |
466 | ||
467 | static void dev_watchdog_down(struct net_device *dev) | |
468 | { | |
932ff279 | 469 | netif_tx_lock_bh(dev); |
1da177e4 | 470 | if (del_timer(&dev->watchdog_timer)) |
15333061 | 471 | dev_put(dev); |
932ff279 | 472 | netif_tx_unlock_bh(dev); |
1da177e4 LT |
473 | } |
474 | ||
bea3348e SH |
475 | /** |
476 | * netif_carrier_on - set carrier | |
477 | * @dev: network device | |
478 | * | |
479 | * Device has detected that carrier. | |
480 | */ | |
0a242efc DV |
481 | void netif_carrier_on(struct net_device *dev) |
482 | { | |
bfaae0f0 | 483 | if (test_and_clear_bit(__LINK_STATE_NOCARRIER, &dev->state)) { |
b4730016 DM |
484 | if (dev->reg_state == NETREG_UNINITIALIZED) |
485 | return; | |
2d3b479d | 486 | atomic_inc(&dev->carrier_changes); |
0a242efc | 487 | linkwatch_fire_event(dev); |
bfaae0f0 JG |
488 | if (netif_running(dev)) |
489 | __netdev_watchdog_up(dev); | |
490 | } | |
0a242efc | 491 | } |
62e3ba1b | 492 | EXPORT_SYMBOL(netif_carrier_on); |
0a242efc | 493 | |
bea3348e SH |
494 | /** |
495 | * netif_carrier_off - clear carrier | |
496 | * @dev: network device | |
497 | * | |
498 | * Device has detected loss of carrier. | |
499 | */ | |
0a242efc DV |
500 | void netif_carrier_off(struct net_device *dev) |
501 | { | |
b4730016 DM |
502 | if (!test_and_set_bit(__LINK_STATE_NOCARRIER, &dev->state)) { |
503 | if (dev->reg_state == NETREG_UNINITIALIZED) | |
504 | return; | |
2d3b479d | 505 | atomic_inc(&dev->carrier_changes); |
0a242efc | 506 | linkwatch_fire_event(dev); |
b4730016 | 507 | } |
0a242efc | 508 | } |
62e3ba1b | 509 | EXPORT_SYMBOL(netif_carrier_off); |
0a242efc | 510 | |
1da177e4 LT |
511 | /* "NOOP" scheduler: the best scheduler, recommended for all interfaces |
512 | under all circumstances. It is difficult to invent anything faster or | |
513 | cheaper. | |
514 | */ | |
515 | ||
520ac30f ED |
516 | static int noop_enqueue(struct sk_buff *skb, struct Qdisc *qdisc, |
517 | struct sk_buff **to_free) | |
1da177e4 | 518 | { |
520ac30f | 519 | __qdisc_drop(skb, to_free); |
1da177e4 LT |
520 | return NET_XMIT_CN; |
521 | } | |
522 | ||
82d567c2 | 523 | static struct sk_buff *noop_dequeue(struct Qdisc *qdisc) |
1da177e4 LT |
524 | { |
525 | return NULL; | |
526 | } | |
527 | ||
20fea08b | 528 | struct Qdisc_ops noop_qdisc_ops __read_mostly = { |
1da177e4 LT |
529 | .id = "noop", |
530 | .priv_size = 0, | |
531 | .enqueue = noop_enqueue, | |
532 | .dequeue = noop_dequeue, | |
99c0db26 | 533 | .peek = noop_dequeue, |
1da177e4 LT |
534 | .owner = THIS_MODULE, |
535 | }; | |
536 | ||
7698b4fc | 537 | static struct netdev_queue noop_netdev_queue = { |
7698b4fc | 538 | .qdisc = &noop_qdisc, |
9f3ffae0 | 539 | .qdisc_sleeping = &noop_qdisc, |
7698b4fc DM |
540 | }; |
541 | ||
1da177e4 LT |
542 | struct Qdisc noop_qdisc = { |
543 | .enqueue = noop_enqueue, | |
544 | .dequeue = noop_dequeue, | |
545 | .flags = TCQ_F_BUILTIN, | |
10297b99 | 546 | .ops = &noop_qdisc_ops, |
83874000 | 547 | .q.lock = __SPIN_LOCK_UNLOCKED(noop_qdisc.q.lock), |
7698b4fc | 548 | .dev_queue = &noop_netdev_queue, |
f9eb8aea | 549 | .running = SEQCNT_ZERO(noop_qdisc.running), |
7b5edbc4 | 550 | .busylock = __SPIN_LOCK_UNLOCKED(noop_qdisc.busylock), |
1da177e4 | 551 | }; |
62e3ba1b | 552 | EXPORT_SYMBOL(noop_qdisc); |
1da177e4 | 553 | |
e63d7dfd AA |
554 | static int noqueue_init(struct Qdisc *qdisc, struct nlattr *opt, |
555 | struct netlink_ext_ack *extack) | |
d66d6c31 PS |
556 | { |
557 | /* register_qdisc() assigns a default of noop_enqueue if unset, | |
558 | * but __dev_queue_xmit() treats noqueue only as such | |
559 | * if this is NULL - so clear it here. */ | |
560 | qdisc->enqueue = NULL; | |
561 | return 0; | |
562 | } | |
563 | ||
564 | struct Qdisc_ops noqueue_qdisc_ops __read_mostly = { | |
1da177e4 LT |
565 | .id = "noqueue", |
566 | .priv_size = 0, | |
d66d6c31 | 567 | .init = noqueue_init, |
1da177e4 LT |
568 | .enqueue = noop_enqueue, |
569 | .dequeue = noop_dequeue, | |
99c0db26 | 570 | .peek = noop_dequeue, |
1da177e4 LT |
571 | .owner = THIS_MODULE, |
572 | }; | |
573 | ||
cc7ec456 ED |
574 | static const u8 prio2band[TC_PRIO_MAX + 1] = { |
575 | 1, 2, 2, 2, 1, 2, 0, 0 , 1, 1, 1, 1, 1, 1, 1, 1 | |
576 | }; | |
d3678b46 DM |
577 | |
578 | /* 3-band FIFO queue: old style, but should be a bit faster than | |
579 | generic prio+fifo combination. | |
580 | */ | |
581 | ||
582 | #define PFIFO_FAST_BANDS 3 | |
583 | ||
fd3ae5e8 KK |
584 | /* |
585 | * Private data for a pfifo_fast scheduler containing: | |
c5ad119f | 586 | * - rings for priority bands |
fd3ae5e8 KK |
587 | */ |
588 | struct pfifo_fast_priv { | |
c5ad119f | 589 | struct skb_array q[PFIFO_FAST_BANDS]; |
fd3ae5e8 KK |
590 | }; |
591 | ||
c5ad119f JF |
592 | static inline struct skb_array *band2list(struct pfifo_fast_priv *priv, |
593 | int band) | |
d3678b46 | 594 | { |
c5ad119f | 595 | return &priv->q[band]; |
d3678b46 DM |
596 | } |
597 | ||
520ac30f ED |
598 | static int pfifo_fast_enqueue(struct sk_buff *skb, struct Qdisc *qdisc, |
599 | struct sk_buff **to_free) | |
321090e7 | 600 | { |
c5ad119f JF |
601 | int band = prio2band[skb->priority & TC_PRIO_MAX]; |
602 | struct pfifo_fast_priv *priv = qdisc_priv(qdisc); | |
603 | struct skb_array *q = band2list(priv, band); | |
604 | int err; | |
821d24ae | 605 | |
c5ad119f JF |
606 | err = skb_array_produce(q, skb); |
607 | ||
608 | if (unlikely(err)) | |
609 | return qdisc_drop_cpu(skb, qdisc, to_free); | |
610 | ||
611 | qdisc_qstats_cpu_qlen_inc(qdisc); | |
612 | qdisc_qstats_cpu_backlog_inc(qdisc, skb); | |
613 | return NET_XMIT_SUCCESS; | |
1da177e4 LT |
614 | } |
615 | ||
cc7ec456 | 616 | static struct sk_buff *pfifo_fast_dequeue(struct Qdisc *qdisc) |
1da177e4 | 617 | { |
fd3ae5e8 | 618 | struct pfifo_fast_priv *priv = qdisc_priv(qdisc); |
c5ad119f JF |
619 | struct sk_buff *skb = NULL; |
620 | int band; | |
ec323368 | 621 | |
c5ad119f JF |
622 | for (band = 0; band < PFIFO_FAST_BANDS && !skb; band++) { |
623 | struct skb_array *q = band2list(priv, band); | |
fd3ae5e8 | 624 | |
c5ad119f JF |
625 | if (__skb_array_empty(q)) |
626 | continue; | |
fd3ae5e8 | 627 | |
c5ad119f JF |
628 | skb = skb_array_consume_bh(q); |
629 | } | |
630 | if (likely(skb)) { | |
631 | qdisc_qstats_cpu_backlog_dec(qdisc, skb); | |
632 | qdisc_bstats_cpu_update(qdisc, skb); | |
633 | qdisc_qstats_cpu_qlen_dec(qdisc); | |
d3678b46 | 634 | } |
f87a9c3d | 635 | |
c5ad119f | 636 | return skb; |
1da177e4 LT |
637 | } |
638 | ||
cc7ec456 | 639 | static struct sk_buff *pfifo_fast_peek(struct Qdisc *qdisc) |
99c0db26 | 640 | { |
fd3ae5e8 | 641 | struct pfifo_fast_priv *priv = qdisc_priv(qdisc); |
c5ad119f JF |
642 | struct sk_buff *skb = NULL; |
643 | int band; | |
fd3ae5e8 | 644 | |
c5ad119f JF |
645 | for (band = 0; band < PFIFO_FAST_BANDS && !skb; band++) { |
646 | struct skb_array *q = band2list(priv, band); | |
99c0db26 | 647 | |
c5ad119f | 648 | skb = __skb_array_peek(q); |
99c0db26 JP |
649 | } |
650 | ||
c5ad119f | 651 | return skb; |
99c0db26 JP |
652 | } |
653 | ||
cc7ec456 | 654 | static void pfifo_fast_reset(struct Qdisc *qdisc) |
1da177e4 | 655 | { |
c5ad119f | 656 | int i, band; |
fd3ae5e8 | 657 | struct pfifo_fast_priv *priv = qdisc_priv(qdisc); |
d3678b46 | 658 | |
c5ad119f JF |
659 | for (band = 0; band < PFIFO_FAST_BANDS; band++) { |
660 | struct skb_array *q = band2list(priv, band); | |
661 | struct sk_buff *skb; | |
d3678b46 | 662 | |
1df94c3c CW |
663 | /* NULL ring is possible if destroy path is due to a failed |
664 | * skb_array_init() in pfifo_fast_init() case. | |
665 | */ | |
666 | if (!q->ring.queue) | |
667 | continue; | |
668 | ||
c5ad119f JF |
669 | while ((skb = skb_array_consume_bh(q)) != NULL) |
670 | kfree_skb(skb); | |
671 | } | |
672 | ||
673 | for_each_possible_cpu(i) { | |
674 | struct gnet_stats_queue *q = per_cpu_ptr(qdisc->cpu_qstats, i); | |
675 | ||
676 | q->backlog = 0; | |
677 | q->qlen = 0; | |
678 | } | |
1da177e4 LT |
679 | } |
680 | ||
d3678b46 DM |
681 | static int pfifo_fast_dump(struct Qdisc *qdisc, struct sk_buff *skb) |
682 | { | |
683 | struct tc_prio_qopt opt = { .bands = PFIFO_FAST_BANDS }; | |
684 | ||
cc7ec456 | 685 | memcpy(&opt.priomap, prio2band, TC_PRIO_MAX + 1); |
1b34ec43 DM |
686 | if (nla_put(skb, TCA_OPTIONS, sizeof(opt), &opt)) |
687 | goto nla_put_failure; | |
d3678b46 DM |
688 | return skb->len; |
689 | ||
690 | nla_put_failure: | |
691 | return -1; | |
692 | } | |
693 | ||
e63d7dfd AA |
694 | static int pfifo_fast_init(struct Qdisc *qdisc, struct nlattr *opt, |
695 | struct netlink_ext_ack *extack) | |
d3678b46 | 696 | { |
c5ad119f | 697 | unsigned int qlen = qdisc_dev(qdisc)->tx_queue_len; |
fd3ae5e8 | 698 | struct pfifo_fast_priv *priv = qdisc_priv(qdisc); |
c5ad119f JF |
699 | int prio; |
700 | ||
701 | /* guard against zero length rings */ | |
702 | if (!qlen) | |
703 | return -EINVAL; | |
d3678b46 | 704 | |
c5ad119f JF |
705 | for (prio = 0; prio < PFIFO_FAST_BANDS; prio++) { |
706 | struct skb_array *q = band2list(priv, prio); | |
707 | int err; | |
708 | ||
709 | err = skb_array_init(q, qlen, GFP_KERNEL); | |
710 | if (err) | |
711 | return -ENOMEM; | |
712 | } | |
d3678b46 | 713 | |
23624935 ED |
714 | /* Can by-pass the queue discipline */ |
715 | qdisc->flags |= TCQ_F_CAN_BYPASS; | |
d3678b46 DM |
716 | return 0; |
717 | } | |
718 | ||
c5ad119f JF |
719 | static void pfifo_fast_destroy(struct Qdisc *sch) |
720 | { | |
721 | struct pfifo_fast_priv *priv = qdisc_priv(sch); | |
722 | int prio; | |
723 | ||
724 | for (prio = 0; prio < PFIFO_FAST_BANDS; prio++) { | |
725 | struct skb_array *q = band2list(priv, prio); | |
726 | ||
727 | /* NULL ring is possible if destroy path is due to a failed | |
728 | * skb_array_init() in pfifo_fast_init() case. | |
729 | */ | |
1df94c3c | 730 | if (!q->ring.queue) |
c5ad119f JF |
731 | continue; |
732 | /* Destroy ring but no need to kfree_skb because a call to | |
733 | * pfifo_fast_reset() has already done that work. | |
734 | */ | |
735 | ptr_ring_cleanup(&q->ring, NULL); | |
736 | } | |
737 | } | |
738 | ||
6ec1c69a | 739 | struct Qdisc_ops pfifo_fast_ops __read_mostly = { |
d3678b46 | 740 | .id = "pfifo_fast", |
fd3ae5e8 | 741 | .priv_size = sizeof(struct pfifo_fast_priv), |
d3678b46 DM |
742 | .enqueue = pfifo_fast_enqueue, |
743 | .dequeue = pfifo_fast_dequeue, | |
99c0db26 | 744 | .peek = pfifo_fast_peek, |
d3678b46 | 745 | .init = pfifo_fast_init, |
c5ad119f | 746 | .destroy = pfifo_fast_destroy, |
d3678b46 DM |
747 | .reset = pfifo_fast_reset, |
748 | .dump = pfifo_fast_dump, | |
1da177e4 | 749 | .owner = THIS_MODULE, |
c5ad119f | 750 | .static_flags = TCQ_F_NOLOCK | TCQ_F_CPUSTATS, |
1da177e4 | 751 | }; |
1f27cde3 | 752 | EXPORT_SYMBOL(pfifo_fast_ops); |
1da177e4 | 753 | |
23d3b8bf | 754 | static struct lock_class_key qdisc_tx_busylock; |
f9eb8aea | 755 | static struct lock_class_key qdisc_running_key; |
23d3b8bf | 756 | |
5ce2d488 | 757 | struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue, |
d2a7f269 | 758 | const struct Qdisc_ops *ops) |
1da177e4 LT |
759 | { |
760 | void *p; | |
761 | struct Qdisc *sch; | |
d276055c | 762 | unsigned int size = QDISC_ALIGN(sizeof(*sch)) + ops->priv_size; |
3d54b82f | 763 | int err = -ENOBUFS; |
26aa0459 JSP |
764 | struct net_device *dev; |
765 | ||
766 | if (!dev_queue) { | |
767 | err = -EINVAL; | |
768 | goto errout; | |
769 | } | |
1da177e4 | 770 | |
26aa0459 | 771 | dev = dev_queue->dev; |
f2cd2d3e ED |
772 | p = kzalloc_node(size, GFP_KERNEL, |
773 | netdev_queue_numa_node_read(dev_queue)); | |
774 | ||
1da177e4 | 775 | if (!p) |
3d54b82f | 776 | goto errout; |
3d54b82f | 777 | sch = (struct Qdisc *) QDISC_ALIGN((unsigned long) p); |
d276055c ED |
778 | /* if we got non aligned memory, ask more and do alignment ourself */ |
779 | if (sch != p) { | |
780 | kfree(p); | |
781 | p = kzalloc_node(size + QDISC_ALIGNTO - 1, GFP_KERNEL, | |
782 | netdev_queue_numa_node_read(dev_queue)); | |
783 | if (!p) | |
784 | goto errout; | |
785 | sch = (struct Qdisc *) QDISC_ALIGN((unsigned long) p); | |
786 | sch->padded = (char *) sch - (char *) p; | |
787 | } | |
a53851e2 | 788 | __skb_queue_head_init(&sch->gso_skb); |
70e57d5e | 789 | __skb_queue_head_init(&sch->skb_bad_txq); |
48da34b7 FW |
790 | qdisc_skb_head_init(&sch->q); |
791 | spin_lock_init(&sch->q.lock); | |
23d3b8bf | 792 | |
d59f5ffa JF |
793 | if (ops->static_flags & TCQ_F_CPUSTATS) { |
794 | sch->cpu_bstats = | |
795 | netdev_alloc_pcpu_stats(struct gnet_stats_basic_cpu); | |
796 | if (!sch->cpu_bstats) | |
797 | goto errout1; | |
798 | ||
799 | sch->cpu_qstats = alloc_percpu(struct gnet_stats_queue); | |
800 | if (!sch->cpu_qstats) { | |
801 | free_percpu(sch->cpu_bstats); | |
802 | goto errout1; | |
803 | } | |
804 | } | |
805 | ||
79640a4c | 806 | spin_lock_init(&sch->busylock); |
23d3b8bf ED |
807 | lockdep_set_class(&sch->busylock, |
808 | dev->qdisc_tx_busylock ?: &qdisc_tx_busylock); | |
809 | ||
f9eb8aea ED |
810 | seqcount_init(&sch->running); |
811 | lockdep_set_class(&sch->running, | |
812 | dev->qdisc_running_key ?: &qdisc_running_key); | |
813 | ||
1da177e4 | 814 | sch->ops = ops; |
d59f5ffa | 815 | sch->flags = ops->static_flags; |
1da177e4 LT |
816 | sch->enqueue = ops->enqueue; |
817 | sch->dequeue = ops->dequeue; | |
bb949fbd | 818 | sch->dev_queue = dev_queue; |
23d3b8bf | 819 | dev_hold(dev); |
7b936405 | 820 | refcount_set(&sch->refcnt, 1); |
3d54b82f TG |
821 | |
822 | return sch; | |
d59f5ffa JF |
823 | errout1: |
824 | kfree(p); | |
3d54b82f | 825 | errout: |
01e123d7 | 826 | return ERR_PTR(err); |
3d54b82f TG |
827 | } |
828 | ||
3511c913 | 829 | struct Qdisc *qdisc_create_dflt(struct netdev_queue *dev_queue, |
d2a7f269 | 830 | const struct Qdisc_ops *ops, |
831 | unsigned int parentid) | |
3d54b82f TG |
832 | { |
833 | struct Qdisc *sch; | |
10297b99 | 834 | |
6da7c8fc | 835 | if (!try_module_get(ops->owner)) |
166ee5b8 | 836 | return NULL; |
6da7c8fc | 837 | |
5ce2d488 | 838 | sch = qdisc_alloc(dev_queue, ops); |
166ee5b8 ED |
839 | if (IS_ERR(sch)) { |
840 | module_put(ops->owner); | |
841 | return NULL; | |
842 | } | |
9f9afec4 | 843 | sch->parent = parentid; |
3d54b82f | 844 | |
e63d7dfd | 845 | if (!ops->init || ops->init(sch, NULL, NULL) == 0) |
1da177e4 LT |
846 | return sch; |
847 | ||
0fbbeb1b | 848 | qdisc_destroy(sch); |
1da177e4 LT |
849 | return NULL; |
850 | } | |
62e3ba1b | 851 | EXPORT_SYMBOL(qdisc_create_dflt); |
1da177e4 | 852 | |
5fb66229 | 853 | /* Under qdisc_lock(qdisc) and BH! */ |
1da177e4 LT |
854 | |
855 | void qdisc_reset(struct Qdisc *qdisc) | |
856 | { | |
20fea08b | 857 | const struct Qdisc_ops *ops = qdisc->ops; |
a53851e2 | 858 | struct sk_buff *skb, *tmp; |
1da177e4 LT |
859 | |
860 | if (ops->reset) | |
861 | ops->reset(qdisc); | |
67305ebc | 862 | |
a53851e2 JF |
863 | skb_queue_walk_safe(&qdisc->gso_skb, skb, tmp) { |
864 | __skb_unlink(skb, &qdisc->gso_skb); | |
865 | kfree_skb_list(skb); | |
bbd8a0d3 | 866 | } |
a53851e2 | 867 | |
70e57d5e JF |
868 | skb_queue_walk_safe(&qdisc->skb_bad_txq, skb, tmp) { |
869 | __skb_unlink(skb, &qdisc->skb_bad_txq); | |
870 | kfree_skb_list(skb); | |
871 | } | |
872 | ||
4d202a0d | 873 | qdisc->q.qlen = 0; |
c8e18129 | 874 | qdisc->qstats.backlog = 0; |
1da177e4 | 875 | } |
62e3ba1b | 876 | EXPORT_SYMBOL(qdisc_reset); |
1da177e4 | 877 | |
752fbcc3 | 878 | static void qdisc_free(struct Qdisc *qdisc) |
5d944c64 | 879 | { |
73c20a8b | 880 | if (qdisc_is_percpu_stats(qdisc)) { |
22e0f8b9 | 881 | free_percpu(qdisc->cpu_bstats); |
73c20a8b JF |
882 | free_percpu(qdisc->cpu_qstats); |
883 | } | |
22e0f8b9 | 884 | |
5d944c64 ED |
885 | kfree((char *) qdisc - qdisc->padded); |
886 | } | |
887 | ||
1e0d5a57 | 888 | void qdisc_destroy(struct Qdisc *qdisc) |
1da177e4 | 889 | { |
8a34c5dc | 890 | const struct Qdisc_ops *ops = qdisc->ops; |
a53851e2 | 891 | struct sk_buff *skb, *tmp; |
8a34c5dc | 892 | |
1e0d5a57 | 893 | if (qdisc->flags & TCQ_F_BUILTIN || |
7b936405 | 894 | !refcount_dec_and_test(&qdisc->refcnt)) |
1e0d5a57 DM |
895 | return; |
896 | ||
3a682fbd | 897 | #ifdef CONFIG_NET_SCHED |
59cc1f61 | 898 | qdisc_hash_del(qdisc); |
f6e0b239 | 899 | |
a2da570d | 900 | qdisc_put_stab(rtnl_dereference(qdisc->stab)); |
3a682fbd | 901 | #endif |
1c0d32fd | 902 | gen_kill_estimator(&qdisc->rate_est); |
8a34c5dc DM |
903 | if (ops->reset) |
904 | ops->reset(qdisc); | |
905 | if (ops->destroy) | |
906 | ops->destroy(qdisc); | |
907 | ||
908 | module_put(ops->owner); | |
909 | dev_put(qdisc_dev(qdisc)); | |
910 | ||
a53851e2 JF |
911 | skb_queue_walk_safe(&qdisc->gso_skb, skb, tmp) { |
912 | __skb_unlink(skb, &qdisc->gso_skb); | |
913 | kfree_skb_list(skb); | |
914 | } | |
915 | ||
70e57d5e JF |
916 | skb_queue_walk_safe(&qdisc->skb_bad_txq, skb, tmp) { |
917 | __skb_unlink(skb, &qdisc->skb_bad_txq); | |
918 | kfree_skb_list(skb); | |
919 | } | |
920 | ||
752fbcc3 | 921 | qdisc_free(qdisc); |
1da177e4 | 922 | } |
62e3ba1b | 923 | EXPORT_SYMBOL(qdisc_destroy); |
1da177e4 | 924 | |
589983cd PM |
925 | /* Attach toplevel qdisc to device queue. */ |
926 | struct Qdisc *dev_graft_qdisc(struct netdev_queue *dev_queue, | |
927 | struct Qdisc *qdisc) | |
928 | { | |
929 | struct Qdisc *oqdisc = dev_queue->qdisc_sleeping; | |
930 | spinlock_t *root_lock; | |
931 | ||
932 | root_lock = qdisc_lock(oqdisc); | |
933 | spin_lock_bh(root_lock); | |
934 | ||
589983cd PM |
935 | /* ... and graft new one */ |
936 | if (qdisc == NULL) | |
937 | qdisc = &noop_qdisc; | |
938 | dev_queue->qdisc_sleeping = qdisc; | |
939 | rcu_assign_pointer(dev_queue->qdisc, &noop_qdisc); | |
940 | ||
941 | spin_unlock_bh(root_lock); | |
942 | ||
943 | return oqdisc; | |
944 | } | |
b8970f0b | 945 | EXPORT_SYMBOL(dev_graft_qdisc); |
589983cd | 946 | |
e8a0464c DM |
947 | static void attach_one_default_qdisc(struct net_device *dev, |
948 | struct netdev_queue *dev_queue, | |
949 | void *_unused) | |
950 | { | |
3e692f21 PS |
951 | struct Qdisc *qdisc; |
952 | const struct Qdisc_ops *ops = default_qdisc_ops; | |
e8a0464c | 953 | |
3e692f21 PS |
954 | if (dev->priv_flags & IFF_NO_QUEUE) |
955 | ops = &noqueue_qdisc_ops; | |
956 | ||
957 | qdisc = qdisc_create_dflt(dev_queue, ops, TC_H_ROOT); | |
958 | if (!qdisc) { | |
959 | netdev_info(dev, "activation failed\n"); | |
960 | return; | |
e8a0464c | 961 | } |
3e692f21 | 962 | if (!netif_is_multiqueue(dev)) |
4eaf3b84 | 963 | qdisc->flags |= TCQ_F_ONETXQUEUE | TCQ_F_NOPARENT; |
e8a0464c DM |
964 | dev_queue->qdisc_sleeping = qdisc; |
965 | } | |
966 | ||
6ec1c69a DM |
967 | static void attach_default_qdiscs(struct net_device *dev) |
968 | { | |
969 | struct netdev_queue *txq; | |
970 | struct Qdisc *qdisc; | |
971 | ||
972 | txq = netdev_get_tx_queue(dev, 0); | |
973 | ||
4b469955 | 974 | if (!netif_is_multiqueue(dev) || |
4b469955 | 975 | dev->priv_flags & IFF_NO_QUEUE) { |
6ec1c69a DM |
976 | netdev_for_each_tx_queue(dev, attach_one_default_qdisc, NULL); |
977 | dev->qdisc = txq->qdisc_sleeping; | |
551143d8 | 978 | qdisc_refcount_inc(dev->qdisc); |
6ec1c69a | 979 | } else { |
3511c913 | 980 | qdisc = qdisc_create_dflt(txq, &mq_qdisc_ops, TC_H_ROOT); |
6ec1c69a | 981 | if (qdisc) { |
6ec1c69a | 982 | dev->qdisc = qdisc; |
e57a784d | 983 | qdisc->ops->attach(qdisc); |
6ec1c69a DM |
984 | } |
985 | } | |
59cc1f61 | 986 | #ifdef CONFIG_NET_SCHED |
92f91706 | 987 | if (dev->qdisc != &noop_qdisc) |
49b49971 | 988 | qdisc_hash_add(dev->qdisc, false); |
59cc1f61 | 989 | #endif |
6ec1c69a DM |
990 | } |
991 | ||
e8a0464c DM |
992 | static void transition_one_qdisc(struct net_device *dev, |
993 | struct netdev_queue *dev_queue, | |
994 | void *_need_watchdog) | |
995 | { | |
83874000 | 996 | struct Qdisc *new_qdisc = dev_queue->qdisc_sleeping; |
e8a0464c DM |
997 | int *need_watchdog_p = _need_watchdog; |
998 | ||
a9312ae8 DM |
999 | if (!(new_qdisc->flags & TCQ_F_BUILTIN)) |
1000 | clear_bit(__QDISC_STATE_DEACTIVATED, &new_qdisc->state); | |
1001 | ||
83874000 | 1002 | rcu_assign_pointer(dev_queue->qdisc, new_qdisc); |
3e692f21 | 1003 | if (need_watchdog_p) { |
9d21493b | 1004 | dev_queue->trans_start = 0; |
e8a0464c | 1005 | *need_watchdog_p = 1; |
9d21493b | 1006 | } |
e8a0464c DM |
1007 | } |
1008 | ||
1da177e4 LT |
1009 | void dev_activate(struct net_device *dev) |
1010 | { | |
e8a0464c | 1011 | int need_watchdog; |
b0e1e646 | 1012 | |
1da177e4 | 1013 | /* No queueing discipline is attached to device; |
6da7c8fc | 1014 | * create default one for devices, which need queueing |
1015 | * and noqueue_qdisc for virtual interfaces | |
1da177e4 LT |
1016 | */ |
1017 | ||
6ec1c69a DM |
1018 | if (dev->qdisc == &noop_qdisc) |
1019 | attach_default_qdiscs(dev); | |
af356afa | 1020 | |
cacaddf5 TC |
1021 | if (!netif_carrier_ok(dev)) |
1022 | /* Delay activation until next carrier-on event */ | |
1023 | return; | |
1024 | ||
e8a0464c DM |
1025 | need_watchdog = 0; |
1026 | netdev_for_each_tx_queue(dev, transition_one_qdisc, &need_watchdog); | |
24824a09 ED |
1027 | if (dev_ingress_queue(dev)) |
1028 | transition_one_qdisc(dev, dev_ingress_queue(dev), NULL); | |
e8a0464c DM |
1029 | |
1030 | if (need_watchdog) { | |
860e9538 | 1031 | netif_trans_update(dev); |
1da177e4 LT |
1032 | dev_watchdog_up(dev); |
1033 | } | |
b0e1e646 | 1034 | } |
b8970f0b | 1035 | EXPORT_SYMBOL(dev_activate); |
b0e1e646 | 1036 | |
e8a0464c DM |
1037 | static void dev_deactivate_queue(struct net_device *dev, |
1038 | struct netdev_queue *dev_queue, | |
1039 | void *_qdisc_default) | |
b0e1e646 | 1040 | { |
e8a0464c | 1041 | struct Qdisc *qdisc_default = _qdisc_default; |
970565bb | 1042 | struct Qdisc *qdisc; |
970565bb | 1043 | |
46e5da40 | 1044 | qdisc = rtnl_dereference(dev_queue->qdisc); |
b0e1e646 | 1045 | if (qdisc) { |
83874000 DM |
1046 | spin_lock_bh(qdisc_lock(qdisc)); |
1047 | ||
a9312ae8 DM |
1048 | if (!(qdisc->flags & TCQ_F_BUILTIN)) |
1049 | set_bit(__QDISC_STATE_DEACTIVATED, &qdisc->state); | |
1050 | ||
f7a54c13 | 1051 | rcu_assign_pointer(dev_queue->qdisc, qdisc_default); |
b0e1e646 | 1052 | qdisc_reset(qdisc); |
d3b753db | 1053 | |
83874000 | 1054 | spin_unlock_bh(qdisc_lock(qdisc)); |
b0e1e646 | 1055 | } |
1da177e4 LT |
1056 | } |
1057 | ||
4335cd2d | 1058 | static bool some_qdisc_is_busy(struct net_device *dev) |
e8a0464c DM |
1059 | { |
1060 | unsigned int i; | |
1061 | ||
1062 | for (i = 0; i < dev->num_tx_queues; i++) { | |
1063 | struct netdev_queue *dev_queue; | |
7698b4fc | 1064 | spinlock_t *root_lock; |
e2627c8c | 1065 | struct Qdisc *q; |
e8a0464c DM |
1066 | int val; |
1067 | ||
1068 | dev_queue = netdev_get_tx_queue(dev, i); | |
b9a3b110 | 1069 | q = dev_queue->qdisc_sleeping; |
e8a0464c | 1070 | |
6b3ba914 JF |
1071 | if (q->flags & TCQ_F_NOLOCK) { |
1072 | val = test_bit(__QDISC_STATE_SCHED, &q->state); | |
1073 | } else { | |
1074 | root_lock = qdisc_lock(q); | |
1075 | spin_lock_bh(root_lock); | |
e8a0464c | 1076 | |
6b3ba914 JF |
1077 | val = (qdisc_is_running(q) || |
1078 | test_bit(__QDISC_STATE_SCHED, &q->state)); | |
e8a0464c | 1079 | |
6b3ba914 JF |
1080 | spin_unlock_bh(root_lock); |
1081 | } | |
e8a0464c DM |
1082 | |
1083 | if (val) | |
1084 | return true; | |
1085 | } | |
1086 | return false; | |
1087 | } | |
1088 | ||
7bbde83b JF |
1089 | static void dev_qdisc_reset(struct net_device *dev, |
1090 | struct netdev_queue *dev_queue, | |
1091 | void *none) | |
1092 | { | |
1093 | struct Qdisc *qdisc = dev_queue->qdisc_sleeping; | |
1094 | ||
1095 | if (qdisc) | |
1096 | qdisc_reset(qdisc); | |
1097 | } | |
1098 | ||
3137663d ED |
1099 | /** |
1100 | * dev_deactivate_many - deactivate transmissions on several devices | |
1101 | * @head: list of devices to deactivate | |
1102 | * | |
1103 | * This function returns only when all outstanding transmissions | |
1104 | * have completed, unless all devices are in dismantle phase. | |
1105 | */ | |
44345724 | 1106 | void dev_deactivate_many(struct list_head *head) |
1da177e4 | 1107 | { |
44345724 | 1108 | struct net_device *dev; |
41a23b07 | 1109 | |
5cde2829 | 1110 | list_for_each_entry(dev, head, close_list) { |
44345724 OP |
1111 | netdev_for_each_tx_queue(dev, dev_deactivate_queue, |
1112 | &noop_qdisc); | |
1113 | if (dev_ingress_queue(dev)) | |
1114 | dev_deactivate_queue(dev, dev_ingress_queue(dev), | |
1115 | &noop_qdisc); | |
1116 | ||
1117 | dev_watchdog_down(dev); | |
1118 | } | |
1da177e4 | 1119 | |
3137663d ED |
1120 | /* Wait for outstanding qdisc-less dev_queue_xmit calls. |
1121 | * This is avoided if all devices are in dismantle phase : | |
1122 | * Caller will call synchronize_net() for us | |
1123 | */ | |
7bbde83b | 1124 | synchronize_net(); |
1da177e4 | 1125 | |
d4828d85 | 1126 | /* Wait for outstanding qdisc_run calls. */ |
7bbde83b | 1127 | list_for_each_entry(dev, head, close_list) { |
44345724 OP |
1128 | while (some_qdisc_is_busy(dev)) |
1129 | yield(); | |
7bbde83b JF |
1130 | /* The new qdisc is assigned at this point so we can safely |
1131 | * unwind stale skb lists and qdisc statistics | |
1132 | */ | |
1133 | netdev_for_each_tx_queue(dev, dev_qdisc_reset, NULL); | |
1134 | if (dev_ingress_queue(dev)) | |
1135 | dev_qdisc_reset(dev, dev_ingress_queue(dev), NULL); | |
1136 | } | |
44345724 OP |
1137 | } |
1138 | ||
1139 | void dev_deactivate(struct net_device *dev) | |
1140 | { | |
1141 | LIST_HEAD(single); | |
1142 | ||
5cde2829 | 1143 | list_add(&dev->close_list, &single); |
44345724 | 1144 | dev_deactivate_many(&single); |
5f04d506 | 1145 | list_del(&single); |
1da177e4 | 1146 | } |
b8970f0b | 1147 | EXPORT_SYMBOL(dev_deactivate); |
1da177e4 | 1148 | |
b0e1e646 DM |
1149 | static void dev_init_scheduler_queue(struct net_device *dev, |
1150 | struct netdev_queue *dev_queue, | |
e8a0464c | 1151 | void *_qdisc) |
b0e1e646 | 1152 | { |
e8a0464c DM |
1153 | struct Qdisc *qdisc = _qdisc; |
1154 | ||
46e5da40 | 1155 | rcu_assign_pointer(dev_queue->qdisc, qdisc); |
b0e1e646 | 1156 | dev_queue->qdisc_sleeping = qdisc; |
a53851e2 | 1157 | __skb_queue_head_init(&qdisc->gso_skb); |
70e57d5e | 1158 | __skb_queue_head_init(&qdisc->skb_bad_txq); |
b0e1e646 DM |
1159 | } |
1160 | ||
1da177e4 LT |
1161 | void dev_init_scheduler(struct net_device *dev) |
1162 | { | |
af356afa | 1163 | dev->qdisc = &noop_qdisc; |
e8a0464c | 1164 | netdev_for_each_tx_queue(dev, dev_init_scheduler_queue, &noop_qdisc); |
24824a09 ED |
1165 | if (dev_ingress_queue(dev)) |
1166 | dev_init_scheduler_queue(dev, dev_ingress_queue(dev), &noop_qdisc); | |
1da177e4 | 1167 | |
cdeabbb8 | 1168 | timer_setup(&dev->watchdog_timer, dev_watchdog, 0); |
1da177e4 LT |
1169 | } |
1170 | ||
e8a0464c DM |
1171 | static void shutdown_scheduler_queue(struct net_device *dev, |
1172 | struct netdev_queue *dev_queue, | |
1173 | void *_qdisc_default) | |
1da177e4 | 1174 | { |
b0e1e646 | 1175 | struct Qdisc *qdisc = dev_queue->qdisc_sleeping; |
e8a0464c | 1176 | struct Qdisc *qdisc_default = _qdisc_default; |
b0e1e646 DM |
1177 | |
1178 | if (qdisc) { | |
f7a54c13 | 1179 | rcu_assign_pointer(dev_queue->qdisc, qdisc_default); |
b0e1e646 | 1180 | dev_queue->qdisc_sleeping = qdisc_default; |
1da177e4 | 1181 | |
1da177e4 | 1182 | qdisc_destroy(qdisc); |
10297b99 | 1183 | } |
b0e1e646 DM |
1184 | } |
1185 | ||
1186 | void dev_shutdown(struct net_device *dev) | |
1187 | { | |
e8a0464c | 1188 | netdev_for_each_tx_queue(dev, shutdown_scheduler_queue, &noop_qdisc); |
24824a09 ED |
1189 | if (dev_ingress_queue(dev)) |
1190 | shutdown_scheduler_queue(dev, dev_ingress_queue(dev), &noop_qdisc); | |
af356afa PM |
1191 | qdisc_destroy(dev->qdisc); |
1192 | dev->qdisc = &noop_qdisc; | |
1193 | ||
547b792c | 1194 | WARN_ON(timer_pending(&dev->watchdog_timer)); |
1da177e4 | 1195 | } |
292f1c7f | 1196 | |
01cb71d2 | 1197 | void psched_ratecfg_precompute(struct psched_ratecfg *r, |
3e1e3aae ED |
1198 | const struct tc_ratespec *conf, |
1199 | u64 rate64) | |
292f1c7f | 1200 | { |
01cb71d2 ED |
1201 | memset(r, 0, sizeof(*r)); |
1202 | r->overhead = conf->overhead; | |
3e1e3aae | 1203 | r->rate_bytes_ps = max_t(u64, conf->rate, rate64); |
8a8e3d84 | 1204 | r->linklayer = (conf->linklayer & TC_LINKLAYER_MASK); |
292f1c7f JP |
1205 | r->mult = 1; |
1206 | /* | |
130d3d68 ED |
1207 | * The deal here is to replace a divide by a reciprocal one |
1208 | * in fast path (a reciprocal divide is a multiply and a shift) | |
1209 | * | |
1210 | * Normal formula would be : | |
1211 | * time_in_ns = (NSEC_PER_SEC * len) / rate_bps | |
1212 | * | |
1213 | * We compute mult/shift to use instead : | |
1214 | * time_in_ns = (len * mult) >> shift; | |
1215 | * | |
1216 | * We try to get the highest possible mult value for accuracy, | |
1217 | * but have to make sure no overflows will ever happen. | |
292f1c7f | 1218 | */ |
130d3d68 ED |
1219 | if (r->rate_bytes_ps > 0) { |
1220 | u64 factor = NSEC_PER_SEC; | |
1221 | ||
1222 | for (;;) { | |
1223 | r->mult = div64_u64(factor, r->rate_bytes_ps); | |
1224 | if (r->mult & (1U << 31) || factor & (1ULL << 63)) | |
292f1c7f | 1225 | break; |
130d3d68 ED |
1226 | factor <<= 1; |
1227 | r->shift++; | |
292f1c7f | 1228 | } |
292f1c7f JP |
1229 | } |
1230 | } | |
1231 | EXPORT_SYMBOL(psched_ratecfg_precompute); | |
46209401 JP |
1232 | |
1233 | static void mini_qdisc_rcu_func(struct rcu_head *head) | |
1234 | { | |
1235 | } | |
1236 | ||
1237 | void mini_qdisc_pair_swap(struct mini_Qdisc_pair *miniqp, | |
1238 | struct tcf_proto *tp_head) | |
1239 | { | |
1240 | struct mini_Qdisc *miniq_old = rtnl_dereference(*miniqp->p_miniq); | |
1241 | struct mini_Qdisc *miniq; | |
1242 | ||
1243 | if (!tp_head) { | |
1244 | RCU_INIT_POINTER(*miniqp->p_miniq, NULL); | |
1245 | return; | |
1246 | } | |
1247 | ||
1248 | miniq = !miniq_old || miniq_old == &miniqp->miniq2 ? | |
1249 | &miniqp->miniq1 : &miniqp->miniq2; | |
1250 | ||
1251 | /* We need to make sure that readers won't see the miniq | |
1252 | * we are about to modify. So wait until previous call_rcu_bh callback | |
1253 | * is done. | |
1254 | */ | |
1255 | rcu_barrier_bh(); | |
1256 | miniq->filter_list = tp_head; | |
1257 | rcu_assign_pointer(*miniqp->p_miniq, miniq); | |
1258 | ||
1259 | if (miniq_old) | |
1260 | /* This is counterpart of the rcu barrier above. We need to | |
1261 | * block potential new user of miniq_old until all readers | |
1262 | * are not seeing it. | |
1263 | */ | |
1264 | call_rcu_bh(&miniq_old->rcu, mini_qdisc_rcu_func); | |
1265 | } | |
1266 | EXPORT_SYMBOL(mini_qdisc_pair_swap); | |
1267 | ||
1268 | void mini_qdisc_pair_init(struct mini_Qdisc_pair *miniqp, struct Qdisc *qdisc, | |
1269 | struct mini_Qdisc __rcu **p_miniq) | |
1270 | { | |
1271 | miniqp->miniq1.cpu_bstats = qdisc->cpu_bstats; | |
1272 | miniqp->miniq1.cpu_qstats = qdisc->cpu_qstats; | |
1273 | miniqp->miniq2.cpu_bstats = qdisc->cpu_bstats; | |
1274 | miniqp->miniq2.cpu_qstats = qdisc->cpu_qstats; | |
1275 | miniqp->p_miniq = p_miniq; | |
1276 | } | |
1277 | EXPORT_SYMBOL(mini_qdisc_pair_init); |