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PCI: Provide common functions for ECAM mapping
[linux-2.6/btrfs-unstable.git] / net / sched / sch_fq_codel.c
blobd3fc8f9dd3d464a23f9ea924fc00154a861eda26
1 /*
2 * Fair Queue CoDel discipline
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 * Copyright (C) 2012,2015 Eric Dumazet <edumazet@google.com>
10 */
11
12 #include <linux/module.h>
13 #include <linux/types.h>
14 #include <linux/kernel.h>
15 #include <linux/jiffies.h>
16 #include <linux/string.h>
17 #include <linux/in.h>
18 #include <linux/errno.h>
19 #include <linux/init.h>
20 #include <linux/skbuff.h>
21 #include <linux/jhash.h>
22 #include <linux/slab.h>
23 #include <linux/vmalloc.h>
24 #include <net/netlink.h>
25 #include <net/pkt_sched.h>
26 #include <net/codel.h>
27
28 /* Fair Queue CoDel.
29 *
30 * Principles :
31 * Packets are classified (internal classifier or external) on flows.
32 * This is a Stochastic model (as we use a hash, several flows
33 * might be hashed on same slot)
34 * Each flow has a CoDel managed queue.
35 * Flows are linked onto two (Round Robin) lists,
36 * so that new flows have priority on old ones.
37 *
38 * For a given flow, packets are not reordered (CoDel uses a FIFO)
39 * head drops only.
40 * ECN capability is on by default.
41 * Low memory footprint (64 bytes per flow)
42 */
43
44 struct fq_codel_flow {
45 struct sk_buff *head;
46 struct sk_buff *tail;
47 struct list_head flowchain;
48 int deficit;
49 u32 dropped; /* number of drops (or ECN marks) on this flow */
50 struct codel_vars cvars;
51 }; /* please try to keep this structure <= 64 bytes */
52
53 struct fq_codel_sched_data {
54 struct tcf_proto __rcu *filter_list; /* optional external classifier */
55 struct fq_codel_flow *flows; /* Flows table [flows_cnt] */
56 u32 *backlogs; /* backlog table [flows_cnt] */
57 u32 flows_cnt; /* number of flows */
58 u32 perturbation; /* hash perturbation */
59 u32 quantum; /* psched_mtu(qdisc_dev(sch)); */
60 struct codel_params cparams;
61 struct codel_stats cstats;
62 u32 drop_overlimit;
63 u32 new_flow_count;
64
65 struct list_head new_flows; /* list of new flows */
66 struct list_head old_flows; /* list of old flows */
67 };
68
69 static unsigned int fq_codel_hash(const struct fq_codel_sched_data *q,
70 struct sk_buff *skb)
71 {
72 u32 hash = skb_get_hash_perturb(skb, q->perturbation);
73
74 return reciprocal_scale(hash, q->flows_cnt);
75 }
76
77 static unsigned int fq_codel_classify(struct sk_buff *skb, struct Qdisc *sch,
78 int *qerr)
79 {
80 struct fq_codel_sched_data *q = qdisc_priv(sch);
81 struct tcf_proto *filter;
82 struct tcf_result res;
83 int result;
84
85 if (TC_H_MAJ(skb->priority) == sch->handle &&
86 TC_H_MIN(skb->priority) > 0 &&
87 TC_H_MIN(skb->priority) <= q->flows_cnt)
88 return TC_H_MIN(skb->priority);
89
90 filter = rcu_dereference_bh(q->filter_list);
91 if (!filter)
92 return fq_codel_hash(q, skb) + 1;
93
94 *qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
95 result = tc_classify(skb, filter, &res, false);
96 if (result >= 0) {
97 #ifdef CONFIG_NET_CLS_ACT
98 switch (result) {
99 case TC_ACT_STOLEN:
100 case TC_ACT_QUEUED:
101 *qerr = NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
102 case TC_ACT_SHOT:
103 return 0;
104 }
105 #endif
106 if (TC_H_MIN(res.classid) <= q->flows_cnt)
107 return TC_H_MIN(res.classid);
108 }
109 return 0;
110 }
111
112 /* helper functions : might be changed when/if skb use a standard list_head */
113
114 /* remove one skb from head of slot queue */
115 static inline struct sk_buff *dequeue_head(struct fq_codel_flow *flow)
116 {
117 struct sk_buff *skb = flow->head;
118
119 flow->head = skb->next;
120 skb->next = NULL;
121 return skb;
122 }
123
124 /* add skb to flow queue (tail add) */
125 static inline void flow_queue_add(struct fq_codel_flow *flow,
126 struct sk_buff *skb)
127 {
128 if (flow->head == NULL)
129 flow->head = skb;
130 else
131 flow->tail->next = skb;
132 flow->tail = skb;
133 skb->next = NULL;
134 }
135
136 static unsigned int fq_codel_drop(struct Qdisc *sch)
137 {
138 struct fq_codel_sched_data *q = qdisc_priv(sch);
139 struct sk_buff *skb;
140 unsigned int maxbacklog = 0, idx = 0, i, len;
141 struct fq_codel_flow *flow;
142
143 /* Queue is full! Find the fat flow and drop packet from it.
144 * This might sound expensive, but with 1024 flows, we scan
145 * 4KB of memory, and we dont need to handle a complex tree
146 * in fast path (packet queue/enqueue) with many cache misses.
147 */
148 for (i = 0; i < q->flows_cnt; i++) {
149 if (q->backlogs[i] > maxbacklog) {
150 maxbacklog = q->backlogs[i];
151 idx = i;
152 }
153 }
154 flow = &q->flows[idx];
155 skb = dequeue_head(flow);
156 len = qdisc_pkt_len(skb);
157 q->backlogs[idx] -= len;
158 sch->q.qlen--;
159 qdisc_qstats_drop(sch);
160 qdisc_qstats_backlog_dec(sch, skb);
161 kfree_skb(skb);
162 flow->dropped++;
163 return idx;
164 }
165
166 static unsigned int fq_codel_qdisc_drop(struct Qdisc *sch)
167 {
168 unsigned int prev_backlog;
169
170 prev_backlog = sch->qstats.backlog;
171 fq_codel_drop(sch);
172 return prev_backlog - sch->qstats.backlog;
173 }
174
175 static int fq_codel_enqueue(struct sk_buff *skb, struct Qdisc *sch)
176 {
177 struct fq_codel_sched_data *q = qdisc_priv(sch);
178 unsigned int idx, prev_backlog;
179 struct fq_codel_flow *flow;
180 int uninitialized_var(ret);
181
182 idx = fq_codel_classify(skb, sch, &ret);
183 if (idx == 0) {
184 if (ret & __NET_XMIT_BYPASS)
185 qdisc_qstats_drop(sch);
186 kfree_skb(skb);
187 return ret;
188 }
189 idx--;
190
191 codel_set_enqueue_time(skb);
192 flow = &q->flows[idx];
193 flow_queue_add(flow, skb);
194 q->backlogs[idx] += qdisc_pkt_len(skb);
195 qdisc_qstats_backlog_inc(sch, skb);
196
197 if (list_empty(&flow->flowchain)) {
198 list_add_tail(&flow->flowchain, &q->new_flows);
199 q->new_flow_count++;
200 flow->deficit = q->quantum;
201 flow->dropped = 0;
202 }
203 if (++sch->q.qlen <= sch->limit)
204 return NET_XMIT_SUCCESS;
205
206 prev_backlog = sch->qstats.backlog;
207 q->drop_overlimit++;
208 /* Return Congestion Notification only if we dropped a packet
209 * from this flow.
210 */
211 if (fq_codel_drop(sch) == idx)
212 return NET_XMIT_CN;
213
214 /* As we dropped a packet, better let upper stack know this */
215 qdisc_tree_reduce_backlog(sch, 1, prev_backlog - sch->qstats.backlog);
216 return NET_XMIT_SUCCESS;
217 }
218
219 /* This is the specific function called from codel_dequeue()
220 * to dequeue a packet from queue. Note: backlog is handled in
221 * codel, we dont need to reduce it here.
222 */
223 static struct sk_buff *dequeue(struct codel_vars *vars, struct Qdisc *sch)
224 {
225 struct fq_codel_sched_data *q = qdisc_priv(sch);
226 struct fq_codel_flow *flow;
227 struct sk_buff *skb = NULL;
228
229 flow = container_of(vars, struct fq_codel_flow, cvars);
230 if (flow->head) {
231 skb = dequeue_head(flow);
232 q->backlogs[flow - q->flows] -= qdisc_pkt_len(skb);
233 sch->q.qlen--;
234 }
235 return skb;
236 }
237
238 static struct sk_buff *fq_codel_dequeue(struct Qdisc *sch)
239 {
240 struct fq_codel_sched_data *q = qdisc_priv(sch);
241 struct sk_buff *skb;
242 struct fq_codel_flow *flow;
243 struct list_head *head;
244 u32 prev_drop_count, prev_ecn_mark;
245 unsigned int prev_backlog;
246
247 begin:
248 head = &q->new_flows;
249 if (list_empty(head)) {
250 head = &q->old_flows;
251 if (list_empty(head))
252 return NULL;
253 }
254 flow = list_first_entry(head, struct fq_codel_flow, flowchain);
255
256 if (flow->deficit <= 0) {
257 flow->deficit += q->quantum;
258 list_move_tail(&flow->flowchain, &q->old_flows);
259 goto begin;
260 }
261
262 prev_drop_count = q->cstats.drop_count;
263 prev_ecn_mark = q->cstats.ecn_mark;
264 prev_backlog = sch->qstats.backlog;
265
266 skb = codel_dequeue(sch, &q->cparams, &flow->cvars, &q->cstats,
267 dequeue);
268
269 flow->dropped += q->cstats.drop_count - prev_drop_count;
270 flow->dropped += q->cstats.ecn_mark - prev_ecn_mark;
271
272 if (!skb) {
273 /* force a pass through old_flows to prevent starvation */
274 if ((head == &q->new_flows) && !list_empty(&q->old_flows))
275 list_move_tail(&flow->flowchain, &q->old_flows);
276 else
277 list_del_init(&flow->flowchain);
278 goto begin;
279 }
280 qdisc_bstats_update(sch, skb);
281 flow->deficit -= qdisc_pkt_len(skb);
282 /* We cant call qdisc_tree_reduce_backlog() if our qlen is 0,
283 * or HTB crashes. Defer it for next round.
284 */
285 if (q->cstats.drop_count && sch->q.qlen) {
286 qdisc_tree_reduce_backlog(sch, q->cstats.drop_count,
287 q->cstats.drop_len);
288 q->cstats.drop_count = 0;
289 q->cstats.drop_len = 0;
290 }
291 return skb;
292 }
293
294 static void fq_codel_reset(struct Qdisc *sch)
295 {
296 struct fq_codel_sched_data *q = qdisc_priv(sch);
297 int i;
298
299 INIT_LIST_HEAD(&q->new_flows);
300 INIT_LIST_HEAD(&q->old_flows);
301 for (i = 0; i < q->flows_cnt; i++) {
302 struct fq_codel_flow *flow = q->flows + i;
303
304 while (flow->head) {
305 struct sk_buff *skb = dequeue_head(flow);
306
307 qdisc_qstats_backlog_dec(sch, skb);
308 kfree_skb(skb);
309 }
310
311 INIT_LIST_HEAD(&flow->flowchain);
312 codel_vars_init(&flow->cvars);
313 }
314 memset(q->backlogs, 0, q->flows_cnt * sizeof(u32));
315 sch->q.qlen = 0;
316 }
317
318 static const struct nla_policy fq_codel_policy[TCA_FQ_CODEL_MAX + 1] = {
319 [TCA_FQ_CODEL_TARGET] = { .type = NLA_U32 },
320 [TCA_FQ_CODEL_LIMIT] = { .type = NLA_U32 },
321 [TCA_FQ_CODEL_INTERVAL] = { .type = NLA_U32 },
322 [TCA_FQ_CODEL_ECN] = { .type = NLA_U32 },
323 [TCA_FQ_CODEL_FLOWS] = { .type = NLA_U32 },
324 [TCA_FQ_CODEL_QUANTUM] = { .type = NLA_U32 },
325 [TCA_FQ_CODEL_CE_THRESHOLD] = { .type = NLA_U32 },
326 };
327
328 static int fq_codel_change(struct Qdisc *sch, struct nlattr *opt)
329 {
330 struct fq_codel_sched_data *q = qdisc_priv(sch);
331 struct nlattr *tb[TCA_FQ_CODEL_MAX + 1];
332 int err;
333
334 if (!opt)
335 return -EINVAL;
336
337 err = nla_parse_nested(tb, TCA_FQ_CODEL_MAX, opt, fq_codel_policy);
338 if (err < 0)
339 return err;
340 if (tb[TCA_FQ_CODEL_FLOWS]) {
341 if (q->flows)
342 return -EINVAL;
343 q->flows_cnt = nla_get_u32(tb[TCA_FQ_CODEL_FLOWS]);
344 if (!q->flows_cnt ||
345 q->flows_cnt > 65536)
346 return -EINVAL;
347 }
348 sch_tree_lock(sch);
349
350 if (tb[TCA_FQ_CODEL_TARGET]) {
351 u64 target = nla_get_u32(tb[TCA_FQ_CODEL_TARGET]);
352
353 q->cparams.target = (target * NSEC_PER_USEC) >> CODEL_SHIFT;
354 }
355
356 if (tb[TCA_FQ_CODEL_CE_THRESHOLD]) {
357 u64 val = nla_get_u32(tb[TCA_FQ_CODEL_CE_THRESHOLD]);
358
359 q->cparams.ce_threshold = (val * NSEC_PER_USEC) >> CODEL_SHIFT;
360 }
361
362 if (tb[TCA_FQ_CODEL_INTERVAL]) {
363 u64 interval = nla_get_u32(tb[TCA_FQ_CODEL_INTERVAL]);
364
365 q->cparams.interval = (interval * NSEC_PER_USEC) >> CODEL_SHIFT;
366 }
367
368 if (tb[TCA_FQ_CODEL_LIMIT])
369 sch->limit = nla_get_u32(tb[TCA_FQ_CODEL_LIMIT]);
370
371 if (tb[TCA_FQ_CODEL_ECN])
372 q->cparams.ecn = !!nla_get_u32(tb[TCA_FQ_CODEL_ECN]);
373
374 if (tb[TCA_FQ_CODEL_QUANTUM])
375 q->quantum = max(256U, nla_get_u32(tb[TCA_FQ_CODEL_QUANTUM]));
376
377 while (sch->q.qlen > sch->limit) {
378 struct sk_buff *skb = fq_codel_dequeue(sch);
379
380 q->cstats.drop_len += qdisc_pkt_len(skb);
381 kfree_skb(skb);
382 q->cstats.drop_count++;
383 }
384 qdisc_tree_reduce_backlog(sch, q->cstats.drop_count, q->cstats.drop_len);
385 q->cstats.drop_count = 0;
386 q->cstats.drop_len = 0;
387
388 sch_tree_unlock(sch);
389 return 0;
390 }
391
392 static void *fq_codel_zalloc(size_t sz)
393 {
394 void *ptr = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN);
395
396 if (!ptr)
397 ptr = vzalloc(sz);
398 return ptr;
399 }
400
401 static void fq_codel_free(void *addr)
402 {
403 kvfree(addr);
404 }
405
406 static void fq_codel_destroy(struct Qdisc *sch)
407 {
408 struct fq_codel_sched_data *q = qdisc_priv(sch);
409
410 tcf_destroy_chain(&q->filter_list);
411 fq_codel_free(q->backlogs);
412 fq_codel_free(q->flows);
413 }
414
415 static int fq_codel_init(struct Qdisc *sch, struct nlattr *opt)
416 {
417 struct fq_codel_sched_data *q = qdisc_priv(sch);
418 int i;
419
420 sch->limit = 10*1024;
421 q->flows_cnt = 1024;
422 q->quantum = psched_mtu(qdisc_dev(sch));
423 q->perturbation = prandom_u32();
424 INIT_LIST_HEAD(&q->new_flows);
425 INIT_LIST_HEAD(&q->old_flows);
426 codel_params_init(&q->cparams, sch);
427 codel_stats_init(&q->cstats);
428 q->cparams.ecn = true;
429
430 if (opt) {
431 int err = fq_codel_change(sch, opt);
432 if (err)
433 return err;
434 }
435
436 if (!q->flows) {
437 q->flows = fq_codel_zalloc(q->flows_cnt *
438 sizeof(struct fq_codel_flow));
439 if (!q->flows)
440 return -ENOMEM;
441 q->backlogs = fq_codel_zalloc(q->flows_cnt * sizeof(u32));
442 if (!q->backlogs) {
443 fq_codel_free(q->flows);
444 return -ENOMEM;
445 }
446 for (i = 0; i < q->flows_cnt; i++) {
447 struct fq_codel_flow *flow = q->flows + i;
448
449 INIT_LIST_HEAD(&flow->flowchain);
450 codel_vars_init(&flow->cvars);
451 }
452 }
453 if (sch->limit >= 1)
454 sch->flags |= TCQ_F_CAN_BYPASS;
455 else
456 sch->flags &= ~TCQ_F_CAN_BYPASS;
457 return 0;
458 }
459
460 static int fq_codel_dump(struct Qdisc *sch, struct sk_buff *skb)
461 {
462 struct fq_codel_sched_data *q = qdisc_priv(sch);
463 struct nlattr *opts;
464
465 opts = nla_nest_start(skb, TCA_OPTIONS);
466 if (opts == NULL)
467 goto nla_put_failure;
468
469 if (nla_put_u32(skb, TCA_FQ_CODEL_TARGET,
470 codel_time_to_us(q->cparams.target)) ||
471 nla_put_u32(skb, TCA_FQ_CODEL_LIMIT,
472 sch->limit) ||
473 nla_put_u32(skb, TCA_FQ_CODEL_INTERVAL,
474 codel_time_to_us(q->cparams.interval)) ||
475 nla_put_u32(skb, TCA_FQ_CODEL_ECN,
476 q->cparams.ecn) ||
477 nla_put_u32(skb, TCA_FQ_CODEL_QUANTUM,
478 q->quantum) ||
479 nla_put_u32(skb, TCA_FQ_CODEL_FLOWS,
480 q->flows_cnt))
481 goto nla_put_failure;
482
483 if (q->cparams.ce_threshold != CODEL_DISABLED_THRESHOLD &&
484 nla_put_u32(skb, TCA_FQ_CODEL_CE_THRESHOLD,
485 codel_time_to_us(q->cparams.ce_threshold)))
486 goto nla_put_failure;
487
488 return nla_nest_end(skb, opts);
489
490 nla_put_failure:
491 return -1;
492 }
493
494 static int fq_codel_dump_stats(struct Qdisc *sch, struct gnet_dump *d)
495 {
496 struct fq_codel_sched_data *q = qdisc_priv(sch);
497 struct tc_fq_codel_xstats st = {
498 .type = TCA_FQ_CODEL_XSTATS_QDISC,
499 };
500 struct list_head *pos;
501
502 st.qdisc_stats.maxpacket = q->cstats.maxpacket;
503 st.qdisc_stats.drop_overlimit = q->drop_overlimit;
504 st.qdisc_stats.ecn_mark = q->cstats.ecn_mark;
505 st.qdisc_stats.new_flow_count = q->new_flow_count;
506 st.qdisc_stats.ce_mark = q->cstats.ce_mark;
507
508 list_for_each(pos, &q->new_flows)
509 st.qdisc_stats.new_flows_len++;
510
511 list_for_each(pos, &q->old_flows)
512 st.qdisc_stats.old_flows_len++;
513
514 return gnet_stats_copy_app(d, &st, sizeof(st));
515 }
516
517 static struct Qdisc *fq_codel_leaf(struct Qdisc *sch, unsigned long arg)
518 {
519 return NULL;
520 }
521
522 static unsigned long fq_codel_get(struct Qdisc *sch, u32 classid)
523 {
524 return 0;
525 }
526
527 static unsigned long fq_codel_bind(struct Qdisc *sch, unsigned long parent,
528 u32 classid)
529 {
530 /* we cannot bypass queue discipline anymore */
531 sch->flags &= ~TCQ_F_CAN_BYPASS;
532 return 0;
533 }
534
535 static void fq_codel_put(struct Qdisc *q, unsigned long cl)
536 {
537 }
538
539 static struct tcf_proto __rcu **fq_codel_find_tcf(struct Qdisc *sch,
540 unsigned long cl)
541 {
542 struct fq_codel_sched_data *q = qdisc_priv(sch);
543
544 if (cl)
545 return NULL;
546 return &q->filter_list;
547 }
548
549 static int fq_codel_dump_class(struct Qdisc *sch, unsigned long cl,
550 struct sk_buff *skb, struct tcmsg *tcm)
551 {
552 tcm->tcm_handle |= TC_H_MIN(cl);
553 return 0;
554 }
555
556 static int fq_codel_dump_class_stats(struct Qdisc *sch, unsigned long cl,
557 struct gnet_dump *d)
558 {
559 struct fq_codel_sched_data *q = qdisc_priv(sch);
560 u32 idx = cl - 1;
561 struct gnet_stats_queue qs = { 0 };
562 struct tc_fq_codel_xstats xstats;
563
564 if (idx < q->flows_cnt) {
565 const struct fq_codel_flow *flow = &q->flows[idx];
566 const struct sk_buff *skb = flow->head;
567
568 memset(&xstats, 0, sizeof(xstats));
569 xstats.type = TCA_FQ_CODEL_XSTATS_CLASS;
570 xstats.class_stats.deficit = flow->deficit;
571 xstats.class_stats.ldelay =
572 codel_time_to_us(flow->cvars.ldelay);
573 xstats.class_stats.count = flow->cvars.count;
574 xstats.class_stats.lastcount = flow->cvars.lastcount;
575 xstats.class_stats.dropping = flow->cvars.dropping;
576 if (flow->cvars.dropping) {
577 codel_tdiff_t delta = flow->cvars.drop_next -
578 codel_get_time();
579
580 xstats.class_stats.drop_next = (delta >= 0) ?
581 codel_time_to_us(delta) :
582 -codel_time_to_us(-delta);
583 }
584 while (skb) {
585 qs.qlen++;
586 skb = skb->next;
587 }
588 qs.backlog = q->backlogs[idx];
589 qs.drops = flow->dropped;
590 }
591 if (gnet_stats_copy_queue(d, NULL, &qs, 0) < 0)
592 return -1;
593 if (idx < q->flows_cnt)
594 return gnet_stats_copy_app(d, &xstats, sizeof(xstats));
595 return 0;
596 }
597
598 static void fq_codel_walk(struct Qdisc *sch, struct qdisc_walker *arg)
599 {
600 struct fq_codel_sched_data *q = qdisc_priv(sch);
601 unsigned int i;
602
603 if (arg->stop)
604 return;
605
606 for (i = 0; i < q->flows_cnt; i++) {
607 if (list_empty(&q->flows[i].flowchain) ||
608 arg->count < arg->skip) {
609 arg->count++;
610 continue;
611 }
612 if (arg->fn(sch, i + 1, arg) < 0) {
613 arg->stop = 1;
614 break;
615 }
616 arg->count++;
617 }
618 }
619
620 static const struct Qdisc_class_ops fq_codel_class_ops = {
621 .leaf = fq_codel_leaf,
622 .get = fq_codel_get,
623 .put = fq_codel_put,
624 .tcf_chain = fq_codel_find_tcf,
625 .bind_tcf = fq_codel_bind,
626 .unbind_tcf = fq_codel_put,
627 .dump = fq_codel_dump_class,
628 .dump_stats = fq_codel_dump_class_stats,
629 .walk = fq_codel_walk,
630 };
631
632 static struct Qdisc_ops fq_codel_qdisc_ops __read_mostly = {
633 .cl_ops = &fq_codel_class_ops,
634 .id = "fq_codel",
635 .priv_size = sizeof(struct fq_codel_sched_data),
636 .enqueue = fq_codel_enqueue,
637 .dequeue = fq_codel_dequeue,
638 .peek = qdisc_peek_dequeued,
639 .drop = fq_codel_qdisc_drop,
640 .init = fq_codel_init,
641 .reset = fq_codel_reset,
642 .destroy = fq_codel_destroy,
643 .change = fq_codel_change,
644 .dump = fq_codel_dump,
645 .dump_stats = fq_codel_dump_stats,
646 .owner = THIS_MODULE,
647 };
648
649 static int __init fq_codel_module_init(void)
650 {
651 return register_qdisc(&fq_codel_qdisc_ops);
652 }
653
654 static void __exit fq_codel_module_exit(void)
655 {
656 unregister_qdisc(&fq_codel_qdisc_ops);
657 }
658
659 module_init(fq_codel_module_init)
660 module_exit(fq_codel_module_exit)
661 MODULE_AUTHOR("Eric Dumazet");
662 MODULE_LICENSE("GPL");
(deprecated) Btrfs devel tree