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> |
292f1c7f | 28 | #include <net/sch_generic.h> |
1da177e4 | 29 | #include <net/pkt_sched.h> |
7fee226a | 30 | #include <net/dst.h> |
1da177e4 LT |
31 | |
32 | /* Main transmission queue. */ | |
33 | ||
0463d4ae | 34 | /* Modifications to data participating in scheduling must be protected with |
5fb66229 | 35 | * qdisc_lock(qdisc) spinlock. |
0463d4ae PM |
36 | * |
37 | * The idea is the following: | |
c7e4f3bb DM |
38 | * - enqueue, dequeue are serialized via qdisc root lock |
39 | * - ingress filtering is also serialized via qdisc root lock | |
0463d4ae | 40 | * - updates to tree and tree walking are only done under the rtnl mutex. |
1da177e4 | 41 | */ |
1da177e4 | 42 | |
37437bb2 | 43 | static inline int dev_requeue_skb(struct sk_buff *skb, struct Qdisc *q) |
c716a81a | 44 | { |
7fee226a | 45 | skb_dst_force(skb); |
6252352d | 46 | q->gso_skb = skb; |
53e91503 | 47 | q->qstats.requeues++; |
bbd8a0d3 | 48 | q->q.qlen++; /* it's still part of the queue */ |
37437bb2 | 49 | __netif_schedule(q); |
6252352d | 50 | |
c716a81a JHS |
51 | return 0; |
52 | } | |
53 | ||
d3b753db | 54 | static inline struct sk_buff *dequeue_skb(struct Qdisc *q) |
c716a81a | 55 | { |
554794de | 56 | struct sk_buff *skb = q->gso_skb; |
1abbe139 | 57 | const struct netdev_queue *txq = q->dev_queue; |
554794de | 58 | |
ebf05982 | 59 | if (unlikely(skb)) { |
ebf05982 | 60 | /* check the reason of requeuing without tx lock first */ |
1abbe139 | 61 | txq = netdev_get_tx_queue(txq->dev, skb_get_queue_mapping(skb)); |
73466498 | 62 | if (!netif_xmit_frozen_or_stopped(txq)) { |
6252352d | 63 | q->gso_skb = NULL; |
bbd8a0d3 KK |
64 | q->q.qlen--; |
65 | } else | |
ebf05982 JP |
66 | skb = NULL; |
67 | } else { | |
1abbe139 ED |
68 | if (!(q->flags & TCQ_F_ONETXQUEUE) || !netif_xmit_frozen_or_stopped(txq)) |
69 | skb = q->dequeue(q); | |
ebf05982 | 70 | } |
c716a81a JHS |
71 | |
72 | return skb; | |
73 | } | |
74 | ||
6c1361a6 | 75 | static inline int handle_dev_cpu_collision(struct sk_buff *skb, |
970565bb | 76 | struct netdev_queue *dev_queue, |
6c1361a6 | 77 | struct Qdisc *q) |
c716a81a | 78 | { |
6c1361a6 | 79 | int ret; |
c716a81a | 80 | |
c773e847 | 81 | if (unlikely(dev_queue->xmit_lock_owner == smp_processor_id())) { |
6c1361a6 KK |
82 | /* |
83 | * Same CPU holding the lock. It may be a transient | |
84 | * configuration error, when hard_start_xmit() recurses. We | |
85 | * detect it by checking xmit owner and drop the packet when | |
86 | * deadloop is detected. Return OK to try the next skb. | |
87 | */ | |
c716a81a | 88 | kfree_skb(skb); |
e87cc472 JP |
89 | net_warn_ratelimited("Dead loop on netdevice %s, fix it urgently!\n", |
90 | dev_queue->dev->name); | |
6c1361a6 KK |
91 | ret = qdisc_qlen(q); |
92 | } else { | |
93 | /* | |
94 | * Another cpu is holding lock, requeue & delay xmits for | |
95 | * some time. | |
96 | */ | |
d6d9ca0f | 97 | __this_cpu_inc(softnet_data.cpu_collision); |
37437bb2 | 98 | ret = dev_requeue_skb(skb, q); |
c716a81a JHS |
99 | } |
100 | ||
6c1361a6 | 101 | return ret; |
c716a81a JHS |
102 | } |
103 | ||
10297b99 | 104 | /* |
bbd8a0d3 KK |
105 | * Transmit one skb, and handle the return status as required. Holding the |
106 | * __QDISC_STATE_RUNNING bit guarantees that only one CPU can execute this | |
107 | * function. | |
6c1361a6 KK |
108 | * |
109 | * Returns to the caller: | |
110 | * 0 - queue is empty or throttled. | |
111 | * >0 - queue is not empty. | |
6c1361a6 | 112 | */ |
bbd8a0d3 KK |
113 | int sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q, |
114 | struct net_device *dev, struct netdev_queue *txq, | |
115 | spinlock_t *root_lock) | |
1da177e4 | 116 | { |
5f1a485d | 117 | int ret = NETDEV_TX_BUSY; |
7698b4fc DM |
118 | |
119 | /* And release qdisc */ | |
120 | spin_unlock(root_lock); | |
c716a81a | 121 | |
c773e847 | 122 | HARD_TX_LOCK(dev, txq, smp_processor_id()); |
73466498 | 123 | if (!netif_xmit_frozen_or_stopped(txq)) |
fd2ea0a7 | 124 | ret = dev_hard_start_xmit(skb, dev, txq); |
572a9d7b | 125 | |
c773e847 | 126 | HARD_TX_UNLOCK(dev, txq); |
c716a81a | 127 | |
7698b4fc | 128 | spin_lock(root_lock); |
c716a81a | 129 | |
9a1654ba JP |
130 | if (dev_xmit_complete(ret)) { |
131 | /* Driver sent out skb successfully or skb was consumed */ | |
6c1361a6 | 132 | ret = qdisc_qlen(q); |
9a1654ba | 133 | } else if (ret == NETDEV_TX_LOCKED) { |
6c1361a6 | 134 | /* Driver try lock failed */ |
eb6aafe3 | 135 | ret = handle_dev_cpu_collision(skb, txq, q); |
9a1654ba | 136 | } else { |
6c1361a6 | 137 | /* Driver returned NETDEV_TX_BUSY - requeue skb */ |
e87cc472 JP |
138 | if (unlikely(ret != NETDEV_TX_BUSY)) |
139 | net_warn_ratelimited("BUG %s code %d qlen %d\n", | |
140 | dev->name, ret, q->q.qlen); | |
6c1361a6 | 141 | |
37437bb2 | 142 | ret = dev_requeue_skb(skb, q); |
6c1361a6 | 143 | } |
c716a81a | 144 | |
73466498 | 145 | if (ret && netif_xmit_frozen_or_stopped(txq)) |
37437bb2 DM |
146 | ret = 0; |
147 | ||
6c1361a6 | 148 | return ret; |
1da177e4 LT |
149 | } |
150 | ||
bbd8a0d3 KK |
151 | /* |
152 | * NOTE: Called under qdisc_lock(q) with locally disabled BH. | |
153 | * | |
154 | * __QDISC_STATE_RUNNING guarantees only one CPU can process | |
155 | * this qdisc at a time. qdisc_lock(q) serializes queue accesses for | |
156 | * this queue. | |
157 | * | |
158 | * netif_tx_lock serializes accesses to device driver. | |
159 | * | |
160 | * qdisc_lock(q) and netif_tx_lock are mutually exclusive, | |
161 | * if one is grabbed, another must be free. | |
162 | * | |
163 | * Note, that this procedure can be called by a watchdog timer | |
164 | * | |
165 | * Returns to the caller: | |
166 | * 0 - queue is empty or throttled. | |
167 | * >0 - queue is not empty. | |
168 | * | |
169 | */ | |
170 | static inline int qdisc_restart(struct Qdisc *q) | |
171 | { | |
172 | struct netdev_queue *txq; | |
173 | struct net_device *dev; | |
174 | spinlock_t *root_lock; | |
175 | struct sk_buff *skb; | |
176 | ||
177 | /* Dequeue packet */ | |
178 | skb = dequeue_skb(q); | |
179 | if (unlikely(!skb)) | |
180 | return 0; | |
7fee226a | 181 | WARN_ON_ONCE(skb_dst_is_noref(skb)); |
bbd8a0d3 KK |
182 | root_lock = qdisc_lock(q); |
183 | dev = qdisc_dev(q); | |
184 | txq = netdev_get_tx_queue(dev, skb_get_queue_mapping(skb)); | |
185 | ||
186 | return sch_direct_xmit(skb, q, dev, txq, root_lock); | |
187 | } | |
188 | ||
37437bb2 | 189 | void __qdisc_run(struct Qdisc *q) |
48d83325 | 190 | { |
d5b8aa1d | 191 | int quota = weight_p; |
2ba2506c | 192 | |
37437bb2 | 193 | while (qdisc_restart(q)) { |
2ba2506c | 194 | /* |
d5b8aa1d | 195 | * Ordered by possible occurrence: Postpone processing if |
196 | * 1. we've exceeded packet quota | |
197 | * 2. another process needs the CPU; | |
2ba2506c | 198 | */ |
f0c50c7c | 199 | if (--quota <= 0 || need_resched()) { |
37437bb2 | 200 | __netif_schedule(q); |
d90df3ad | 201 | break; |
2ba2506c HX |
202 | } |
203 | } | |
48d83325 | 204 | |
bc135b23 | 205 | qdisc_run_end(q); |
48d83325 HX |
206 | } |
207 | ||
9d21493b ED |
208 | unsigned long dev_trans_start(struct net_device *dev) |
209 | { | |
210 | unsigned long val, res = dev->trans_start; | |
211 | unsigned int i; | |
212 | ||
213 | for (i = 0; i < dev->num_tx_queues; i++) { | |
214 | val = netdev_get_tx_queue(dev, i)->trans_start; | |
215 | if (val && time_after(val, res)) | |
216 | res = val; | |
217 | } | |
218 | dev->trans_start = res; | |
219 | return res; | |
220 | } | |
221 | EXPORT_SYMBOL(dev_trans_start); | |
222 | ||
1da177e4 LT |
223 | static void dev_watchdog(unsigned long arg) |
224 | { | |
225 | struct net_device *dev = (struct net_device *)arg; | |
226 | ||
932ff279 | 227 | netif_tx_lock(dev); |
e8a0464c | 228 | if (!qdisc_tx_is_noop(dev)) { |
1da177e4 LT |
229 | if (netif_device_present(dev) && |
230 | netif_running(dev) && | |
231 | netif_carrier_ok(dev)) { | |
9d21493b | 232 | int some_queue_timedout = 0; |
e8a0464c | 233 | unsigned int i; |
9d21493b | 234 | unsigned long trans_start; |
e8a0464c DM |
235 | |
236 | for (i = 0; i < dev->num_tx_queues; i++) { | |
237 | struct netdev_queue *txq; | |
238 | ||
239 | txq = netdev_get_tx_queue(dev, i); | |
9d21493b ED |
240 | /* |
241 | * old device drivers set dev->trans_start | |
242 | */ | |
243 | trans_start = txq->trans_start ? : dev->trans_start; | |
73466498 | 244 | if (netif_xmit_stopped(txq) && |
9d21493b ED |
245 | time_after(jiffies, (trans_start + |
246 | dev->watchdog_timeo))) { | |
247 | some_queue_timedout = 1; | |
ccf5ff69 | 248 | txq->trans_timeout++; |
e8a0464c DM |
249 | break; |
250 | } | |
251 | } | |
338f7566 | 252 | |
9d21493b | 253 | if (some_queue_timedout) { |
9d21493b | 254 | WARN_ONCE(1, KERN_INFO "NETDEV WATCHDOG: %s (%s): transmit queue %u timed out\n", |
3019de12 | 255 | dev->name, netdev_drivername(dev), i); |
d314774c | 256 | dev->netdev_ops->ndo_tx_timeout(dev); |
1da177e4 | 257 | } |
e8a0464c DM |
258 | if (!mod_timer(&dev->watchdog_timer, |
259 | round_jiffies(jiffies + | |
260 | dev->watchdog_timeo))) | |
1da177e4 LT |
261 | dev_hold(dev); |
262 | } | |
263 | } | |
932ff279 | 264 | netif_tx_unlock(dev); |
1da177e4 LT |
265 | |
266 | dev_put(dev); | |
267 | } | |
268 | ||
1da177e4 LT |
269 | void __netdev_watchdog_up(struct net_device *dev) |
270 | { | |
d314774c | 271 | if (dev->netdev_ops->ndo_tx_timeout) { |
1da177e4 LT |
272 | if (dev->watchdog_timeo <= 0) |
273 | dev->watchdog_timeo = 5*HZ; | |
60468d5b VP |
274 | if (!mod_timer(&dev->watchdog_timer, |
275 | round_jiffies(jiffies + dev->watchdog_timeo))) | |
1da177e4 LT |
276 | dev_hold(dev); |
277 | } | |
278 | } | |
279 | ||
280 | static void dev_watchdog_up(struct net_device *dev) | |
281 | { | |
1da177e4 | 282 | __netdev_watchdog_up(dev); |
1da177e4 LT |
283 | } |
284 | ||
285 | static void dev_watchdog_down(struct net_device *dev) | |
286 | { | |
932ff279 | 287 | netif_tx_lock_bh(dev); |
1da177e4 | 288 | if (del_timer(&dev->watchdog_timer)) |
15333061 | 289 | dev_put(dev); |
932ff279 | 290 | netif_tx_unlock_bh(dev); |
1da177e4 LT |
291 | } |
292 | ||
bea3348e SH |
293 | /** |
294 | * netif_carrier_on - set carrier | |
295 | * @dev: network device | |
296 | * | |
297 | * Device has detected that carrier. | |
298 | */ | |
0a242efc DV |
299 | void netif_carrier_on(struct net_device *dev) |
300 | { | |
bfaae0f0 | 301 | if (test_and_clear_bit(__LINK_STATE_NOCARRIER, &dev->state)) { |
b4730016 DM |
302 | if (dev->reg_state == NETREG_UNINITIALIZED) |
303 | return; | |
0a242efc | 304 | linkwatch_fire_event(dev); |
bfaae0f0 JG |
305 | if (netif_running(dev)) |
306 | __netdev_watchdog_up(dev); | |
307 | } | |
0a242efc | 308 | } |
62e3ba1b | 309 | EXPORT_SYMBOL(netif_carrier_on); |
0a242efc | 310 | |
bea3348e SH |
311 | /** |
312 | * netif_carrier_off - clear carrier | |
313 | * @dev: network device | |
314 | * | |
315 | * Device has detected loss of carrier. | |
316 | */ | |
0a242efc DV |
317 | void netif_carrier_off(struct net_device *dev) |
318 | { | |
b4730016 DM |
319 | if (!test_and_set_bit(__LINK_STATE_NOCARRIER, &dev->state)) { |
320 | if (dev->reg_state == NETREG_UNINITIALIZED) | |
321 | return; | |
0a242efc | 322 | linkwatch_fire_event(dev); |
b4730016 | 323 | } |
0a242efc | 324 | } |
62e3ba1b | 325 | EXPORT_SYMBOL(netif_carrier_off); |
0a242efc | 326 | |
1da177e4 LT |
327 | /* "NOOP" scheduler: the best scheduler, recommended for all interfaces |
328 | under all circumstances. It is difficult to invent anything faster or | |
329 | cheaper. | |
330 | */ | |
331 | ||
94df109a | 332 | static int noop_enqueue(struct sk_buff *skb, struct Qdisc * qdisc) |
1da177e4 LT |
333 | { |
334 | kfree_skb(skb); | |
335 | return NET_XMIT_CN; | |
336 | } | |
337 | ||
94df109a | 338 | static struct sk_buff *noop_dequeue(struct Qdisc * qdisc) |
1da177e4 LT |
339 | { |
340 | return NULL; | |
341 | } | |
342 | ||
20fea08b | 343 | struct Qdisc_ops noop_qdisc_ops __read_mostly = { |
1da177e4 LT |
344 | .id = "noop", |
345 | .priv_size = 0, | |
346 | .enqueue = noop_enqueue, | |
347 | .dequeue = noop_dequeue, | |
99c0db26 | 348 | .peek = noop_dequeue, |
1da177e4 LT |
349 | .owner = THIS_MODULE, |
350 | }; | |
351 | ||
7698b4fc | 352 | static struct netdev_queue noop_netdev_queue = { |
7698b4fc | 353 | .qdisc = &noop_qdisc, |
9f3ffae0 | 354 | .qdisc_sleeping = &noop_qdisc, |
7698b4fc DM |
355 | }; |
356 | ||
1da177e4 LT |
357 | struct Qdisc noop_qdisc = { |
358 | .enqueue = noop_enqueue, | |
359 | .dequeue = noop_dequeue, | |
360 | .flags = TCQ_F_BUILTIN, | |
10297b99 | 361 | .ops = &noop_qdisc_ops, |
1da177e4 | 362 | .list = LIST_HEAD_INIT(noop_qdisc.list), |
83874000 | 363 | .q.lock = __SPIN_LOCK_UNLOCKED(noop_qdisc.q.lock), |
7698b4fc | 364 | .dev_queue = &noop_netdev_queue, |
7b5edbc4 | 365 | .busylock = __SPIN_LOCK_UNLOCKED(noop_qdisc.busylock), |
1da177e4 | 366 | }; |
62e3ba1b | 367 | EXPORT_SYMBOL(noop_qdisc); |
1da177e4 | 368 | |
20fea08b | 369 | static struct Qdisc_ops noqueue_qdisc_ops __read_mostly = { |
1da177e4 LT |
370 | .id = "noqueue", |
371 | .priv_size = 0, | |
372 | .enqueue = noop_enqueue, | |
373 | .dequeue = noop_dequeue, | |
99c0db26 | 374 | .peek = noop_dequeue, |
1da177e4 LT |
375 | .owner = THIS_MODULE, |
376 | }; | |
377 | ||
30ee42be DM |
378 | static struct Qdisc noqueue_qdisc; |
379 | static struct netdev_queue noqueue_netdev_queue = { | |
380 | .qdisc = &noqueue_qdisc, | |
9f3ffae0 | 381 | .qdisc_sleeping = &noqueue_qdisc, |
30ee42be DM |
382 | }; |
383 | ||
1da177e4 LT |
384 | static struct Qdisc noqueue_qdisc = { |
385 | .enqueue = NULL, | |
386 | .dequeue = noop_dequeue, | |
387 | .flags = TCQ_F_BUILTIN, | |
388 | .ops = &noqueue_qdisc_ops, | |
389 | .list = LIST_HEAD_INIT(noqueue_qdisc.list), | |
30ee42be DM |
390 | .q.lock = __SPIN_LOCK_UNLOCKED(noqueue_qdisc.q.lock), |
391 | .dev_queue = &noqueue_netdev_queue, | |
7b5edbc4 | 392 | .busylock = __SPIN_LOCK_UNLOCKED(noqueue_qdisc.busylock), |
1da177e4 LT |
393 | }; |
394 | ||
395 | ||
cc7ec456 ED |
396 | static const u8 prio2band[TC_PRIO_MAX + 1] = { |
397 | 1, 2, 2, 2, 1, 2, 0, 0 , 1, 1, 1, 1, 1, 1, 1, 1 | |
398 | }; | |
d3678b46 DM |
399 | |
400 | /* 3-band FIFO queue: old style, but should be a bit faster than | |
401 | generic prio+fifo combination. | |
402 | */ | |
403 | ||
404 | #define PFIFO_FAST_BANDS 3 | |
405 | ||
fd3ae5e8 KK |
406 | /* |
407 | * Private data for a pfifo_fast scheduler containing: | |
408 | * - queues for the three band | |
409 | * - bitmap indicating which of the bands contain skbs | |
410 | */ | |
411 | struct pfifo_fast_priv { | |
412 | u32 bitmap; | |
413 | struct sk_buff_head q[PFIFO_FAST_BANDS]; | |
414 | }; | |
415 | ||
416 | /* | |
417 | * Convert a bitmap to the first band number where an skb is queued, where: | |
418 | * bitmap=0 means there are no skbs on any band. | |
419 | * bitmap=1 means there is an skb on band 0. | |
420 | * bitmap=7 means there are skbs on all 3 bands, etc. | |
421 | */ | |
422 | static const int bitmap2band[] = {-1, 0, 1, 0, 2, 0, 1, 0}; | |
423 | ||
424 | static inline struct sk_buff_head *band2list(struct pfifo_fast_priv *priv, | |
425 | int band) | |
d3678b46 | 426 | { |
fd3ae5e8 | 427 | return priv->q + band; |
d3678b46 DM |
428 | } |
429 | ||
cc7ec456 | 430 | static int pfifo_fast_enqueue(struct sk_buff *skb, struct Qdisc *qdisc) |
321090e7 | 431 | { |
a453e068 KK |
432 | if (skb_queue_len(&qdisc->q) < qdisc_dev(qdisc)->tx_queue_len) { |
433 | int band = prio2band[skb->priority & TC_PRIO_MAX]; | |
434 | struct pfifo_fast_priv *priv = qdisc_priv(qdisc); | |
435 | struct sk_buff_head *list = band2list(priv, band); | |
1da177e4 | 436 | |
fd3ae5e8 | 437 | priv->bitmap |= (1 << band); |
d3678b46 | 438 | qdisc->q.qlen++; |
821d24ae | 439 | return __qdisc_enqueue_tail(skb, qdisc, list); |
d3678b46 | 440 | } |
821d24ae TG |
441 | |
442 | return qdisc_drop(skb, qdisc); | |
1da177e4 LT |
443 | } |
444 | ||
cc7ec456 | 445 | static struct sk_buff *pfifo_fast_dequeue(struct Qdisc *qdisc) |
1da177e4 | 446 | { |
fd3ae5e8 KK |
447 | struct pfifo_fast_priv *priv = qdisc_priv(qdisc); |
448 | int band = bitmap2band[priv->bitmap]; | |
1da177e4 | 449 | |
fd3ae5e8 KK |
450 | if (likely(band >= 0)) { |
451 | struct sk_buff_head *list = band2list(priv, band); | |
452 | struct sk_buff *skb = __qdisc_dequeue_head(qdisc, list); | |
453 | ||
454 | qdisc->q.qlen--; | |
455 | if (skb_queue_empty(list)) | |
456 | priv->bitmap &= ~(1 << band); | |
457 | ||
458 | return skb; | |
d3678b46 | 459 | } |
f87a9c3d | 460 | |
1da177e4 LT |
461 | return NULL; |
462 | } | |
463 | ||
cc7ec456 | 464 | static struct sk_buff *pfifo_fast_peek(struct Qdisc *qdisc) |
99c0db26 | 465 | { |
fd3ae5e8 KK |
466 | struct pfifo_fast_priv *priv = qdisc_priv(qdisc); |
467 | int band = bitmap2band[priv->bitmap]; | |
468 | ||
469 | if (band >= 0) { | |
470 | struct sk_buff_head *list = band2list(priv, band); | |
99c0db26 | 471 | |
fd3ae5e8 | 472 | return skb_peek(list); |
99c0db26 JP |
473 | } |
474 | ||
475 | return NULL; | |
476 | } | |
477 | ||
cc7ec456 | 478 | static void pfifo_fast_reset(struct Qdisc *qdisc) |
1da177e4 | 479 | { |
d3678b46 | 480 | int prio; |
fd3ae5e8 | 481 | struct pfifo_fast_priv *priv = qdisc_priv(qdisc); |
d3678b46 DM |
482 | |
483 | for (prio = 0; prio < PFIFO_FAST_BANDS; prio++) | |
fd3ae5e8 | 484 | __qdisc_reset_queue(qdisc, band2list(priv, prio)); |
d3678b46 | 485 | |
fd3ae5e8 | 486 | priv->bitmap = 0; |
821d24ae | 487 | qdisc->qstats.backlog = 0; |
d3678b46 | 488 | qdisc->q.qlen = 0; |
1da177e4 LT |
489 | } |
490 | ||
d3678b46 DM |
491 | static int pfifo_fast_dump(struct Qdisc *qdisc, struct sk_buff *skb) |
492 | { | |
493 | struct tc_prio_qopt opt = { .bands = PFIFO_FAST_BANDS }; | |
494 | ||
cc7ec456 | 495 | memcpy(&opt.priomap, prio2band, TC_PRIO_MAX + 1); |
1b34ec43 DM |
496 | if (nla_put(skb, TCA_OPTIONS, sizeof(opt), &opt)) |
497 | goto nla_put_failure; | |
d3678b46 DM |
498 | return skb->len; |
499 | ||
500 | nla_put_failure: | |
501 | return -1; | |
502 | } | |
503 | ||
504 | static int pfifo_fast_init(struct Qdisc *qdisc, struct nlattr *opt) | |
505 | { | |
506 | int prio; | |
fd3ae5e8 | 507 | struct pfifo_fast_priv *priv = qdisc_priv(qdisc); |
d3678b46 DM |
508 | |
509 | for (prio = 0; prio < PFIFO_FAST_BANDS; prio++) | |
fd3ae5e8 | 510 | skb_queue_head_init(band2list(priv, prio)); |
d3678b46 | 511 | |
23624935 ED |
512 | /* Can by-pass the queue discipline */ |
513 | qdisc->flags |= TCQ_F_CAN_BYPASS; | |
d3678b46 DM |
514 | return 0; |
515 | } | |
516 | ||
6ec1c69a | 517 | struct Qdisc_ops pfifo_fast_ops __read_mostly = { |
d3678b46 | 518 | .id = "pfifo_fast", |
fd3ae5e8 | 519 | .priv_size = sizeof(struct pfifo_fast_priv), |
d3678b46 DM |
520 | .enqueue = pfifo_fast_enqueue, |
521 | .dequeue = pfifo_fast_dequeue, | |
99c0db26 | 522 | .peek = pfifo_fast_peek, |
d3678b46 DM |
523 | .init = pfifo_fast_init, |
524 | .reset = pfifo_fast_reset, | |
525 | .dump = pfifo_fast_dump, | |
1da177e4 LT |
526 | .owner = THIS_MODULE, |
527 | }; | |
b8970f0b | 528 | EXPORT_SYMBOL(pfifo_fast_ops); |
1da177e4 | 529 | |
23d3b8bf ED |
530 | static struct lock_class_key qdisc_tx_busylock; |
531 | ||
5ce2d488 | 532 | struct Qdisc *qdisc_alloc(struct netdev_queue *dev_queue, |
bb949fbd | 533 | struct Qdisc_ops *ops) |
1da177e4 LT |
534 | { |
535 | void *p; | |
536 | struct Qdisc *sch; | |
d276055c | 537 | unsigned int size = QDISC_ALIGN(sizeof(*sch)) + ops->priv_size; |
3d54b82f | 538 | int err = -ENOBUFS; |
23d3b8bf | 539 | struct net_device *dev = dev_queue->dev; |
1da177e4 | 540 | |
f2cd2d3e ED |
541 | p = kzalloc_node(size, GFP_KERNEL, |
542 | netdev_queue_numa_node_read(dev_queue)); | |
543 | ||
1da177e4 | 544 | if (!p) |
3d54b82f | 545 | goto errout; |
3d54b82f | 546 | sch = (struct Qdisc *) QDISC_ALIGN((unsigned long) p); |
d276055c ED |
547 | /* if we got non aligned memory, ask more and do alignment ourself */ |
548 | if (sch != p) { | |
549 | kfree(p); | |
550 | p = kzalloc_node(size + QDISC_ALIGNTO - 1, GFP_KERNEL, | |
551 | netdev_queue_numa_node_read(dev_queue)); | |
552 | if (!p) | |
553 | goto errout; | |
554 | sch = (struct Qdisc *) QDISC_ALIGN((unsigned long) p); | |
555 | sch->padded = (char *) sch - (char *) p; | |
556 | } | |
1da177e4 LT |
557 | INIT_LIST_HEAD(&sch->list); |
558 | skb_queue_head_init(&sch->q); | |
23d3b8bf | 559 | |
79640a4c | 560 | spin_lock_init(&sch->busylock); |
23d3b8bf ED |
561 | lockdep_set_class(&sch->busylock, |
562 | dev->qdisc_tx_busylock ?: &qdisc_tx_busylock); | |
563 | ||
1da177e4 LT |
564 | sch->ops = ops; |
565 | sch->enqueue = ops->enqueue; | |
566 | sch->dequeue = ops->dequeue; | |
bb949fbd | 567 | sch->dev_queue = dev_queue; |
23d3b8bf | 568 | dev_hold(dev); |
1da177e4 | 569 | atomic_set(&sch->refcnt, 1); |
3d54b82f TG |
570 | |
571 | return sch; | |
572 | errout: | |
01e123d7 | 573 | return ERR_PTR(err); |
3d54b82f TG |
574 | } |
575 | ||
3511c913 CG |
576 | struct Qdisc *qdisc_create_dflt(struct netdev_queue *dev_queue, |
577 | struct Qdisc_ops *ops, unsigned int parentid) | |
3d54b82f TG |
578 | { |
579 | struct Qdisc *sch; | |
10297b99 | 580 | |
5ce2d488 | 581 | sch = qdisc_alloc(dev_queue, ops); |
3d54b82f TG |
582 | if (IS_ERR(sch)) |
583 | goto errout; | |
9f9afec4 | 584 | sch->parent = parentid; |
3d54b82f | 585 | |
1da177e4 LT |
586 | if (!ops->init || ops->init(sch, NULL) == 0) |
587 | return sch; | |
588 | ||
0fbbeb1b | 589 | qdisc_destroy(sch); |
3d54b82f | 590 | errout: |
1da177e4 LT |
591 | return NULL; |
592 | } | |
62e3ba1b | 593 | EXPORT_SYMBOL(qdisc_create_dflt); |
1da177e4 | 594 | |
5fb66229 | 595 | /* Under qdisc_lock(qdisc) and BH! */ |
1da177e4 LT |
596 | |
597 | void qdisc_reset(struct Qdisc *qdisc) | |
598 | { | |
20fea08b | 599 | const struct Qdisc_ops *ops = qdisc->ops; |
1da177e4 LT |
600 | |
601 | if (ops->reset) | |
602 | ops->reset(qdisc); | |
67305ebc | 603 | |
bbd8a0d3 KK |
604 | if (qdisc->gso_skb) { |
605 | kfree_skb(qdisc->gso_skb); | |
606 | qdisc->gso_skb = NULL; | |
607 | qdisc->q.qlen = 0; | |
608 | } | |
1da177e4 | 609 | } |
62e3ba1b | 610 | EXPORT_SYMBOL(qdisc_reset); |
1da177e4 | 611 | |
5d944c64 ED |
612 | static void qdisc_rcu_free(struct rcu_head *head) |
613 | { | |
614 | struct Qdisc *qdisc = container_of(head, struct Qdisc, rcu_head); | |
615 | ||
616 | kfree((char *) qdisc - qdisc->padded); | |
617 | } | |
618 | ||
1e0d5a57 | 619 | void qdisc_destroy(struct Qdisc *qdisc) |
1da177e4 | 620 | { |
8a34c5dc DM |
621 | const struct Qdisc_ops *ops = qdisc->ops; |
622 | ||
1e0d5a57 DM |
623 | if (qdisc->flags & TCQ_F_BUILTIN || |
624 | !atomic_dec_and_test(&qdisc->refcnt)) | |
625 | return; | |
626 | ||
3a682fbd | 627 | #ifdef CONFIG_NET_SCHED |
f6e0b239 JP |
628 | qdisc_list_del(qdisc); |
629 | ||
a2da570d | 630 | qdisc_put_stab(rtnl_dereference(qdisc->stab)); |
3a682fbd | 631 | #endif |
8a34c5dc DM |
632 | gen_kill_estimator(&qdisc->bstats, &qdisc->rate_est); |
633 | if (ops->reset) | |
634 | ops->reset(qdisc); | |
635 | if (ops->destroy) | |
636 | ops->destroy(qdisc); | |
637 | ||
638 | module_put(ops->owner); | |
639 | dev_put(qdisc_dev(qdisc)); | |
640 | ||
554794de | 641 | kfree_skb(qdisc->gso_skb); |
5d944c64 ED |
642 | /* |
643 | * gen_estimator est_timer() might access qdisc->q.lock, | |
644 | * wait a RCU grace period before freeing qdisc. | |
645 | */ | |
646 | call_rcu(&qdisc->rcu_head, qdisc_rcu_free); | |
1da177e4 | 647 | } |
62e3ba1b | 648 | EXPORT_SYMBOL(qdisc_destroy); |
1da177e4 | 649 | |
589983cd PM |
650 | /* Attach toplevel qdisc to device queue. */ |
651 | struct Qdisc *dev_graft_qdisc(struct netdev_queue *dev_queue, | |
652 | struct Qdisc *qdisc) | |
653 | { | |
654 | struct Qdisc *oqdisc = dev_queue->qdisc_sleeping; | |
655 | spinlock_t *root_lock; | |
656 | ||
657 | root_lock = qdisc_lock(oqdisc); | |
658 | spin_lock_bh(root_lock); | |
659 | ||
660 | /* Prune old scheduler */ | |
661 | if (oqdisc && atomic_read(&oqdisc->refcnt) <= 1) | |
662 | qdisc_reset(oqdisc); | |
663 | ||
664 | /* ... and graft new one */ | |
665 | if (qdisc == NULL) | |
666 | qdisc = &noop_qdisc; | |
667 | dev_queue->qdisc_sleeping = qdisc; | |
668 | rcu_assign_pointer(dev_queue->qdisc, &noop_qdisc); | |
669 | ||
670 | spin_unlock_bh(root_lock); | |
671 | ||
672 | return oqdisc; | |
673 | } | |
b8970f0b | 674 | EXPORT_SYMBOL(dev_graft_qdisc); |
589983cd | 675 | |
e8a0464c DM |
676 | static void attach_one_default_qdisc(struct net_device *dev, |
677 | struct netdev_queue *dev_queue, | |
678 | void *_unused) | |
679 | { | |
cc7ec456 | 680 | struct Qdisc *qdisc = &noqueue_qdisc; |
e8a0464c DM |
681 | |
682 | if (dev->tx_queue_len) { | |
3511c913 | 683 | qdisc = qdisc_create_dflt(dev_queue, |
d3678b46 | 684 | &pfifo_fast_ops, TC_H_ROOT); |
e8a0464c | 685 | if (!qdisc) { |
cc7ec456 | 686 | netdev_info(dev, "activation failed\n"); |
e8a0464c DM |
687 | return; |
688 | } | |
1abbe139 ED |
689 | if (!netif_is_multiqueue(dev)) |
690 | qdisc->flags |= TCQ_F_ONETXQUEUE; | |
e8a0464c DM |
691 | } |
692 | dev_queue->qdisc_sleeping = qdisc; | |
693 | } | |
694 | ||
6ec1c69a DM |
695 | static void attach_default_qdiscs(struct net_device *dev) |
696 | { | |
697 | struct netdev_queue *txq; | |
698 | struct Qdisc *qdisc; | |
699 | ||
700 | txq = netdev_get_tx_queue(dev, 0); | |
701 | ||
702 | if (!netif_is_multiqueue(dev) || dev->tx_queue_len == 0) { | |
703 | netdev_for_each_tx_queue(dev, attach_one_default_qdisc, NULL); | |
704 | dev->qdisc = txq->qdisc_sleeping; | |
705 | atomic_inc(&dev->qdisc->refcnt); | |
706 | } else { | |
3511c913 | 707 | qdisc = qdisc_create_dflt(txq, &mq_qdisc_ops, TC_H_ROOT); |
6ec1c69a DM |
708 | if (qdisc) { |
709 | qdisc->ops->attach(qdisc); | |
710 | dev->qdisc = qdisc; | |
711 | } | |
712 | } | |
713 | } | |
714 | ||
e8a0464c DM |
715 | static void transition_one_qdisc(struct net_device *dev, |
716 | struct netdev_queue *dev_queue, | |
717 | void *_need_watchdog) | |
718 | { | |
83874000 | 719 | struct Qdisc *new_qdisc = dev_queue->qdisc_sleeping; |
e8a0464c DM |
720 | int *need_watchdog_p = _need_watchdog; |
721 | ||
a9312ae8 DM |
722 | if (!(new_qdisc->flags & TCQ_F_BUILTIN)) |
723 | clear_bit(__QDISC_STATE_DEACTIVATED, &new_qdisc->state); | |
724 | ||
83874000 | 725 | rcu_assign_pointer(dev_queue->qdisc, new_qdisc); |
9d21493b ED |
726 | if (need_watchdog_p && new_qdisc != &noqueue_qdisc) { |
727 | dev_queue->trans_start = 0; | |
e8a0464c | 728 | *need_watchdog_p = 1; |
9d21493b | 729 | } |
e8a0464c DM |
730 | } |
731 | ||
1da177e4 LT |
732 | void dev_activate(struct net_device *dev) |
733 | { | |
e8a0464c | 734 | int need_watchdog; |
b0e1e646 | 735 | |
1da177e4 | 736 | /* No queueing discipline is attached to device; |
d3678b46 DM |
737 | create default one i.e. pfifo_fast for devices, |
738 | which need queueing and noqueue_qdisc for | |
739 | virtual interfaces | |
1da177e4 LT |
740 | */ |
741 | ||
6ec1c69a DM |
742 | if (dev->qdisc == &noop_qdisc) |
743 | attach_default_qdiscs(dev); | |
af356afa | 744 | |
cacaddf5 TC |
745 | if (!netif_carrier_ok(dev)) |
746 | /* Delay activation until next carrier-on event */ | |
747 | return; | |
748 | ||
e8a0464c DM |
749 | need_watchdog = 0; |
750 | netdev_for_each_tx_queue(dev, transition_one_qdisc, &need_watchdog); | |
24824a09 ED |
751 | if (dev_ingress_queue(dev)) |
752 | transition_one_qdisc(dev, dev_ingress_queue(dev), NULL); | |
e8a0464c DM |
753 | |
754 | if (need_watchdog) { | |
1da177e4 LT |
755 | dev->trans_start = jiffies; |
756 | dev_watchdog_up(dev); | |
757 | } | |
b0e1e646 | 758 | } |
b8970f0b | 759 | EXPORT_SYMBOL(dev_activate); |
b0e1e646 | 760 | |
e8a0464c DM |
761 | static void dev_deactivate_queue(struct net_device *dev, |
762 | struct netdev_queue *dev_queue, | |
763 | void *_qdisc_default) | |
b0e1e646 | 764 | { |
e8a0464c | 765 | struct Qdisc *qdisc_default = _qdisc_default; |
970565bb | 766 | struct Qdisc *qdisc; |
970565bb | 767 | |
970565bb | 768 | qdisc = dev_queue->qdisc; |
b0e1e646 | 769 | if (qdisc) { |
83874000 DM |
770 | spin_lock_bh(qdisc_lock(qdisc)); |
771 | ||
a9312ae8 DM |
772 | if (!(qdisc->flags & TCQ_F_BUILTIN)) |
773 | set_bit(__QDISC_STATE_DEACTIVATED, &qdisc->state); | |
774 | ||
f7a54c13 | 775 | rcu_assign_pointer(dev_queue->qdisc, qdisc_default); |
b0e1e646 | 776 | qdisc_reset(qdisc); |
d3b753db | 777 | |
83874000 | 778 | spin_unlock_bh(qdisc_lock(qdisc)); |
b0e1e646 | 779 | } |
1da177e4 LT |
780 | } |
781 | ||
4335cd2d | 782 | static bool some_qdisc_is_busy(struct net_device *dev) |
e8a0464c DM |
783 | { |
784 | unsigned int i; | |
785 | ||
786 | for (i = 0; i < dev->num_tx_queues; i++) { | |
787 | struct netdev_queue *dev_queue; | |
7698b4fc | 788 | spinlock_t *root_lock; |
e2627c8c | 789 | struct Qdisc *q; |
e8a0464c DM |
790 | int val; |
791 | ||
792 | dev_queue = netdev_get_tx_queue(dev, i); | |
b9a3b110 | 793 | q = dev_queue->qdisc_sleeping; |
5fb66229 | 794 | root_lock = qdisc_lock(q); |
e8a0464c | 795 | |
4335cd2d | 796 | spin_lock_bh(root_lock); |
e8a0464c | 797 | |
bc135b23 | 798 | val = (qdisc_is_running(q) || |
b9a3b110 | 799 | test_bit(__QDISC_STATE_SCHED, &q->state)); |
e8a0464c | 800 | |
4335cd2d | 801 | spin_unlock_bh(root_lock); |
e8a0464c DM |
802 | |
803 | if (val) | |
804 | return true; | |
805 | } | |
806 | return false; | |
807 | } | |
808 | ||
3137663d ED |
809 | /** |
810 | * dev_deactivate_many - deactivate transmissions on several devices | |
811 | * @head: list of devices to deactivate | |
812 | * | |
813 | * This function returns only when all outstanding transmissions | |
814 | * have completed, unless all devices are in dismantle phase. | |
815 | */ | |
44345724 | 816 | void dev_deactivate_many(struct list_head *head) |
1da177e4 | 817 | { |
44345724 | 818 | struct net_device *dev; |
3137663d | 819 | bool sync_needed = false; |
41a23b07 | 820 | |
44345724 OP |
821 | list_for_each_entry(dev, head, unreg_list) { |
822 | netdev_for_each_tx_queue(dev, dev_deactivate_queue, | |
823 | &noop_qdisc); | |
824 | if (dev_ingress_queue(dev)) | |
825 | dev_deactivate_queue(dev, dev_ingress_queue(dev), | |
826 | &noop_qdisc); | |
827 | ||
828 | dev_watchdog_down(dev); | |
3137663d | 829 | sync_needed |= !dev->dismantle; |
44345724 | 830 | } |
1da177e4 | 831 | |
3137663d ED |
832 | /* Wait for outstanding qdisc-less dev_queue_xmit calls. |
833 | * This is avoided if all devices are in dismantle phase : | |
834 | * Caller will call synchronize_net() for us | |
835 | */ | |
836 | if (sync_needed) | |
837 | synchronize_net(); | |
1da177e4 | 838 | |
d4828d85 | 839 | /* Wait for outstanding qdisc_run calls. */ |
44345724 OP |
840 | list_for_each_entry(dev, head, unreg_list) |
841 | while (some_qdisc_is_busy(dev)) | |
842 | yield(); | |
843 | } | |
844 | ||
845 | void dev_deactivate(struct net_device *dev) | |
846 | { | |
847 | LIST_HEAD(single); | |
848 | ||
849 | list_add(&dev->unreg_list, &single); | |
850 | dev_deactivate_many(&single); | |
5f04d506 | 851 | list_del(&single); |
1da177e4 | 852 | } |
b8970f0b | 853 | EXPORT_SYMBOL(dev_deactivate); |
1da177e4 | 854 | |
b0e1e646 DM |
855 | static void dev_init_scheduler_queue(struct net_device *dev, |
856 | struct netdev_queue *dev_queue, | |
e8a0464c | 857 | void *_qdisc) |
b0e1e646 | 858 | { |
e8a0464c DM |
859 | struct Qdisc *qdisc = _qdisc; |
860 | ||
b0e1e646 DM |
861 | dev_queue->qdisc = qdisc; |
862 | dev_queue->qdisc_sleeping = qdisc; | |
b0e1e646 DM |
863 | } |
864 | ||
1da177e4 LT |
865 | void dev_init_scheduler(struct net_device *dev) |
866 | { | |
af356afa | 867 | dev->qdisc = &noop_qdisc; |
e8a0464c | 868 | netdev_for_each_tx_queue(dev, dev_init_scheduler_queue, &noop_qdisc); |
24824a09 ED |
869 | if (dev_ingress_queue(dev)) |
870 | dev_init_scheduler_queue(dev, dev_ingress_queue(dev), &noop_qdisc); | |
1da177e4 | 871 | |
b24b8a24 | 872 | setup_timer(&dev->watchdog_timer, dev_watchdog, (unsigned long)dev); |
1da177e4 LT |
873 | } |
874 | ||
e8a0464c DM |
875 | static void shutdown_scheduler_queue(struct net_device *dev, |
876 | struct netdev_queue *dev_queue, | |
877 | void *_qdisc_default) | |
1da177e4 | 878 | { |
b0e1e646 | 879 | struct Qdisc *qdisc = dev_queue->qdisc_sleeping; |
e8a0464c | 880 | struct Qdisc *qdisc_default = _qdisc_default; |
b0e1e646 DM |
881 | |
882 | if (qdisc) { | |
f7a54c13 | 883 | rcu_assign_pointer(dev_queue->qdisc, qdisc_default); |
b0e1e646 | 884 | dev_queue->qdisc_sleeping = qdisc_default; |
1da177e4 | 885 | |
1da177e4 | 886 | qdisc_destroy(qdisc); |
10297b99 | 887 | } |
b0e1e646 DM |
888 | } |
889 | ||
890 | void dev_shutdown(struct net_device *dev) | |
891 | { | |
e8a0464c | 892 | netdev_for_each_tx_queue(dev, shutdown_scheduler_queue, &noop_qdisc); |
24824a09 ED |
893 | if (dev_ingress_queue(dev)) |
894 | shutdown_scheduler_queue(dev, dev_ingress_queue(dev), &noop_qdisc); | |
af356afa PM |
895 | qdisc_destroy(dev->qdisc); |
896 | dev->qdisc = &noop_qdisc; | |
897 | ||
547b792c | 898 | WARN_ON(timer_pending(&dev->watchdog_timer)); |
1da177e4 | 899 | } |
292f1c7f | 900 | |
01cb71d2 ED |
901 | void psched_ratecfg_precompute(struct psched_ratecfg *r, |
902 | const struct tc_ratespec *conf) | |
292f1c7f JP |
903 | { |
904 | u64 factor; | |
905 | u64 mult; | |
906 | int shift; | |
907 | ||
01cb71d2 ED |
908 | memset(r, 0, sizeof(*r)); |
909 | r->overhead = conf->overhead; | |
910 | r->rate_bps = (u64)conf->rate << 3; | |
292f1c7f JP |
911 | r->mult = 1; |
912 | /* | |
913 | * Calibrate mult, shift so that token counting is accurate | |
914 | * for smallest packet size (64 bytes). Token (time in ns) is | |
915 | * computed as (bytes * 8) * NSEC_PER_SEC / rate_bps. It will | |
916 | * work as long as the smallest packet transfer time can be | |
917 | * accurately represented in nanosec. | |
918 | */ | |
919 | if (r->rate_bps > 0) { | |
920 | /* | |
921 | * Higher shift gives better accuracy. Find the largest | |
922 | * shift such that mult fits in 32 bits. | |
923 | */ | |
924 | for (shift = 0; shift < 16; shift++) { | |
925 | r->shift = shift; | |
926 | factor = 8LLU * NSEC_PER_SEC * (1 << r->shift); | |
927 | mult = div64_u64(factor, r->rate_bps); | |
928 | if (mult > UINT_MAX) | |
929 | break; | |
930 | } | |
931 | ||
932 | r->shift = shift - 1; | |
933 | factor = 8LLU * NSEC_PER_SEC * (1 << r->shift); | |
934 | r->mult = div64_u64(factor, r->rate_bps); | |
935 | } | |
936 | } | |
937 | EXPORT_SYMBOL(psched_ratecfg_precompute); |