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"); 663