1 /* 2 * FQ_Codel - The FlowQueue-Codel scheduler/AQM 3 * 4 * $FreeBSD$ 5 * 6 * Copyright (C) 2016 Centre for Advanced Internet Architectures, 7 * Swinburne University of Technology, Melbourne, Australia. 8 * Portions of this code were made possible in part by a gift from 9 * The Comcast Innovation Fund. 10 * Implemented by Rasool Al-Saadi <ralsaadi@swin.edu.au> 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #ifdef _KERNEL 35 #include <sys/malloc.h> 36 #include <sys/socket.h> 37 //#include <sys/socketvar.h> 38 #include <sys/kernel.h> 39 #include <sys/mbuf.h> 40 #include <sys/module.h> 41 #include <net/if.h> /* IFNAMSIZ */ 42 #include <netinet/in.h> 43 #include <netinet/ip_var.h> /* ipfw_rule_ref */ 44 #include <netinet/ip_fw.h> /* flow_id */ 45 #include <netinet/ip_dummynet.h> 46 47 #include <sys/lock.h> 48 #include <sys/proc.h> 49 #include <sys/rwlock.h> 50 51 #include <netpfil/ipfw/ip_fw_private.h> 52 #include <sys/sysctl.h> 53 #include <netinet/ip.h> 54 #include <netinet/ip6.h> 55 #include <netinet/ip_icmp.h> 56 #include <netinet/tcp.h> 57 #include <netinet/udp.h> 58 #include <sys/queue.h> 59 #include <sys/hash.h> 60 61 #include <netpfil/ipfw/dn_heap.h> 62 #include <netpfil/ipfw/ip_dn_private.h> 63 64 #include <netpfil/ipfw/dn_aqm.h> 65 #include <netpfil/ipfw/dn_aqm_codel.h> 66 #include <netpfil/ipfw/dn_sched.h> 67 #include <netpfil/ipfw/dn_sched_fq_codel.h> 68 #include <netpfil/ipfw/dn_sched_fq_codel_helper.h> 69 70 #else 71 #include <dn_test.h> 72 #endif 73 74 /* NOTE: In fq_codel module, we reimplements CoDel AQM functions 75 * because fq_codel use different flows (sub-queues) structure and 76 * dn_queue includes many variables not needed by a flow (sub-queue 77 * )i.e. avoid extra overhead (88 bytes vs 208 bytes). 78 * Also, CoDel functions manages stats of sub-queues as well as the main queue. 79 */ 80 81 #define DN_SCHED_FQ_CODEL 6 82 83 static struct dn_alg fq_codel_desc; 84 85 /* fq_codel default parameters including codel */ 86 struct dn_sch_fq_codel_parms 87 fq_codel_sysctl = {{5000 * AQM_TIME_1US, 100000 * AQM_TIME_1US, 88 CODEL_ECN_ENABLED}, 1024, 10240, 1514}; 89 90 static int 91 fqcodel_sysctl_interval_handler(SYSCTL_HANDLER_ARGS) 92 { 93 int error; 94 long value; 95 96 value = fq_codel_sysctl.ccfg.interval; 97 value /= AQM_TIME_1US; 98 error = sysctl_handle_long(oidp, &value, 0, req); 99 if (error != 0 || req->newptr == NULL) 100 return (error); 101 if (value < 1 || value > 100 * AQM_TIME_1S) 102 return (EINVAL); 103 fq_codel_sysctl.ccfg.interval = value * AQM_TIME_1US ; 104 105 return (0); 106 } 107 108 static int 109 fqcodel_sysctl_target_handler(SYSCTL_HANDLER_ARGS) 110 { 111 int error; 112 long value; 113 114 value = fq_codel_sysctl.ccfg.target; 115 value /= AQM_TIME_1US; 116 error = sysctl_handle_long(oidp, &value, 0, req); 117 if (error != 0 || req->newptr == NULL) 118 return (error); 119 if (value < 1 || value > 5 * AQM_TIME_1S) 120 return (EINVAL); 121 fq_codel_sysctl.ccfg.target = value * AQM_TIME_1US ; 122 123 return (0); 124 } 125 126 SYSBEGIN(f4) 127 128 SYSCTL_DECL(_net_inet); 129 SYSCTL_DECL(_net_inet_ip); 130 SYSCTL_DECL(_net_inet_ip_dummynet); 131 static SYSCTL_NODE(_net_inet_ip_dummynet, OID_AUTO, fqcodel, 132 CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 133 "FQ_CODEL"); 134 135 #ifdef SYSCTL_NODE 136 137 SYSCTL_PROC(_net_inet_ip_dummynet_fqcodel, OID_AUTO, target, 138 CTLTYPE_LONG | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 139 NULL, 0, fqcodel_sysctl_target_handler, "L", 140 "FQ_CoDel target in microsecond"); 141 SYSCTL_PROC(_net_inet_ip_dummynet_fqcodel, OID_AUTO, interval, 142 CTLTYPE_LONG | CTLFLAG_RW | CTLFLAG_NEEDGIANT, 143 NULL, 0, fqcodel_sysctl_interval_handler, "L", 144 "FQ_CoDel interval in microsecond"); 145 146 SYSCTL_UINT(_net_inet_ip_dummynet_fqcodel, OID_AUTO, quantum, 147 CTLFLAG_RW, &fq_codel_sysctl.quantum, 1514, "FQ_CoDel quantum"); 148 SYSCTL_UINT(_net_inet_ip_dummynet_fqcodel, OID_AUTO, flows, 149 CTLFLAG_RW, &fq_codel_sysctl.flows_cnt, 1024, 150 "Number of queues for FQ_CoDel"); 151 SYSCTL_UINT(_net_inet_ip_dummynet_fqcodel, OID_AUTO, limit, 152 CTLFLAG_RW, &fq_codel_sysctl.limit, 10240, "FQ_CoDel queues size limit"); 153 #endif 154 155 /* Drop a packet form the head of codel queue */ 156 static void 157 codel_drop_head(struct fq_codel_flow *q, struct fq_codel_si *si) 158 { 159 struct mbuf *m = q->mq.head; 160 161 if (m == NULL) 162 return; 163 q->mq.head = m->m_nextpkt; 164 165 fq_update_stats(q, si, -m->m_pkthdr.len, 1); 166 167 if (si->main_q.ni.length == 0) /* queue is now idle */ 168 si->main_q.q_time = dn_cfg.curr_time; 169 170 FREE_PKT(m); 171 } 172 173 /* Enqueue a packet 'm' to a queue 'q' and add timestamp to that packet. 174 * Return 1 when unable to add timestamp, otherwise return 0 175 */ 176 static int 177 codel_enqueue(struct fq_codel_flow *q, struct mbuf *m, struct fq_codel_si *si) 178 { 179 uint64_t len; 180 181 len = m->m_pkthdr.len; 182 /* finding maximum packet size */ 183 if (len > q->cst.maxpkt_size) 184 q->cst.maxpkt_size = len; 185 186 /* Add timestamp to mbuf as MTAG */ 187 struct m_tag *mtag; 188 mtag = m_tag_locate(m, MTAG_ABI_COMPAT, DN_AQM_MTAG_TS, NULL); 189 if (mtag == NULL) 190 mtag = m_tag_alloc(MTAG_ABI_COMPAT, DN_AQM_MTAG_TS, sizeof(aqm_time_t), 191 M_NOWAIT); 192 if (mtag == NULL) 193 goto drop; 194 *(aqm_time_t *)(mtag + 1) = AQM_UNOW; 195 m_tag_prepend(m, mtag); 196 197 mq_append(&q->mq, m); 198 fq_update_stats(q, si, len, 0); 199 return 0; 200 201 drop: 202 fq_update_stats(q, si, len, 1); 203 m_freem(m); 204 return 1; 205 } 206 207 /* 208 * Classify a packet to queue number using Jenkins hash function. 209 * Return: queue number 210 * the input of the hash are protocol no, perturbation, src IP, dst IP, 211 * src port, dst port, 212 */ 213 static inline int 214 fq_codel_classify_flow(struct mbuf *m, uint16_t fcount, struct fq_codel_si *si) 215 { 216 struct ip *ip; 217 struct tcphdr *th; 218 struct udphdr *uh; 219 uint8_t tuple[41]; 220 uint16_t hash=0; 221 222 ip = (struct ip *)mtodo(m, dn_tag_get(m)->iphdr_off); 223 //#ifdef INET6 224 struct ip6_hdr *ip6; 225 int isip6; 226 isip6 = (ip->ip_v == 6); 227 228 if(isip6) { 229 ip6 = (struct ip6_hdr *)ip; 230 *((uint8_t *) &tuple[0]) = ip6->ip6_nxt; 231 *((uint32_t *) &tuple[1]) = si->perturbation; 232 memcpy(&tuple[5], ip6->ip6_src.s6_addr, 16); 233 memcpy(&tuple[21], ip6->ip6_dst.s6_addr, 16); 234 235 switch (ip6->ip6_nxt) { 236 case IPPROTO_TCP: 237 th = (struct tcphdr *)(ip6 + 1); 238 *((uint16_t *) &tuple[37]) = th->th_dport; 239 *((uint16_t *) &tuple[39]) = th->th_sport; 240 break; 241 242 case IPPROTO_UDP: 243 uh = (struct udphdr *)(ip6 + 1); 244 *((uint16_t *) &tuple[37]) = uh->uh_dport; 245 *((uint16_t *) &tuple[39]) = uh->uh_sport; 246 break; 247 default: 248 memset(&tuple[37], 0, 4); 249 } 250 251 hash = jenkins_hash(tuple, 41, HASHINIT) % fcount; 252 return hash; 253 } 254 //#endif 255 256 /* IPv4 */ 257 *((uint8_t *) &tuple[0]) = ip->ip_p; 258 *((uint32_t *) &tuple[1]) = si->perturbation; 259 *((uint32_t *) &tuple[5]) = ip->ip_src.s_addr; 260 *((uint32_t *) &tuple[9]) = ip->ip_dst.s_addr; 261 262 switch (ip->ip_p) { 263 case IPPROTO_TCP: 264 th = (struct tcphdr *)(ip + 1); 265 *((uint16_t *) &tuple[13]) = th->th_dport; 266 *((uint16_t *) &tuple[15]) = th->th_sport; 267 break; 268 269 case IPPROTO_UDP: 270 uh = (struct udphdr *)(ip + 1); 271 *((uint16_t *) &tuple[13]) = uh->uh_dport; 272 *((uint16_t *) &tuple[15]) = uh->uh_sport; 273 break; 274 default: 275 memset(&tuple[13], 0, 4); 276 } 277 hash = jenkins_hash(tuple, 17, HASHINIT) % fcount; 278 279 return hash; 280 } 281 282 /* 283 * Enqueue a packet into an appropriate queue according to 284 * FQ_CODEL algorithm. 285 */ 286 static int 287 fq_codel_enqueue(struct dn_sch_inst *_si, struct dn_queue *_q, 288 struct mbuf *m) 289 { 290 struct fq_codel_si *si; 291 struct fq_codel_schk *schk; 292 struct dn_sch_fq_codel_parms *param; 293 struct dn_queue *mainq; 294 int idx, drop, i, maxidx; 295 296 mainq = (struct dn_queue *)(_si + 1); 297 si = (struct fq_codel_si *)_si; 298 schk = (struct fq_codel_schk *)(si->_si.sched+1); 299 param = &schk->cfg; 300 301 /* classify a packet to queue number*/ 302 idx = fq_codel_classify_flow(m, param->flows_cnt, si); 303 /* enqueue packet into appropriate queue using CoDel AQM. 304 * Note: 'codel_enqueue' function returns 1 only when it unable to 305 * add timestamp to packet (no limit check)*/ 306 drop = codel_enqueue(&si->flows[idx], m, si); 307 308 /* codel unable to timestamp a packet */ 309 if (drop) 310 return 1; 311 312 /* If the flow (sub-queue) is not active ,then add it to the tail of 313 * new flows list, initialize and activate it. 314 */ 315 if (!si->flows[idx].active ) { 316 STAILQ_INSERT_TAIL(&si->newflows, &si->flows[idx], flowchain); 317 si->flows[idx].deficit = param->quantum; 318 si->flows[idx].cst.dropping = false; 319 si->flows[idx].cst.first_above_time = 0; 320 si->flows[idx].active = 1; 321 //D("activate %d",idx); 322 } 323 324 /* check the limit for all queues and remove a packet from the 325 * largest one 326 */ 327 if (mainq->ni.length > schk->cfg.limit) { D("over limit"); 328 /* find first active flow */ 329 for (maxidx = 0; maxidx < schk->cfg.flows_cnt; maxidx++) 330 if (si->flows[maxidx].active) 331 break; 332 if (maxidx < schk->cfg.flows_cnt) { 333 /* find the largest sub- queue */ 334 for (i = maxidx + 1; i < schk->cfg.flows_cnt; i++) 335 if (si->flows[i].active && si->flows[i].stats.length > 336 si->flows[maxidx].stats.length) 337 maxidx = i; 338 codel_drop_head(&si->flows[maxidx], si); 339 D("maxidx = %d",maxidx); 340 drop = 1; 341 } 342 } 343 344 return drop; 345 } 346 347 /* 348 * Dequeue a packet from an appropriate queue according to 349 * FQ_CODEL algorithm. 350 */ 351 static struct mbuf * 352 fq_codel_dequeue(struct dn_sch_inst *_si) 353 { 354 struct fq_codel_si *si; 355 struct fq_codel_schk *schk; 356 struct dn_sch_fq_codel_parms *param; 357 struct fq_codel_flow *f; 358 struct mbuf *mbuf; 359 struct fq_codel_list *fq_codel_flowlist; 360 361 si = (struct fq_codel_si *)_si; 362 schk = (struct fq_codel_schk *)(si->_si.sched+1); 363 param = &schk->cfg; 364 365 do { 366 /* select a list to start with */ 367 if (STAILQ_EMPTY(&si->newflows)) 368 fq_codel_flowlist = &si->oldflows; 369 else 370 fq_codel_flowlist = &si->newflows; 371 372 /* Both new and old queue lists are empty, return NULL */ 373 if (STAILQ_EMPTY(fq_codel_flowlist)) 374 return NULL; 375 376 f = STAILQ_FIRST(fq_codel_flowlist); 377 while (f != NULL) { 378 /* if there is no flow(sub-queue) deficit, increase deficit 379 * by quantum, move the flow to the tail of old flows list 380 * and try another flow. 381 * Otherwise, the flow will be used for dequeue. 382 */ 383 if (f->deficit < 0) { 384 f->deficit += param->quantum; 385 STAILQ_REMOVE_HEAD(fq_codel_flowlist, flowchain); 386 STAILQ_INSERT_TAIL(&si->oldflows, f, flowchain); 387 } else 388 break; 389 390 f = STAILQ_FIRST(fq_codel_flowlist); 391 } 392 393 /* the new flows list is empty, try old flows list */ 394 if (STAILQ_EMPTY(fq_codel_flowlist)) 395 continue; 396 397 /* Dequeue a packet from the selected flow */ 398 mbuf = fqc_codel_dequeue(f, si); 399 400 /* Codel did not return a packet */ 401 if (!mbuf) { 402 /* If the selected flow belongs to new flows list, then move 403 * it to the tail of old flows list. Otherwise, deactivate it and 404 * remove it from the old list and 405 */ 406 if (fq_codel_flowlist == &si->newflows) { 407 STAILQ_REMOVE_HEAD(fq_codel_flowlist, flowchain); 408 STAILQ_INSERT_TAIL(&si->oldflows, f, flowchain); 409 } else { 410 f->active = 0; 411 STAILQ_REMOVE_HEAD(fq_codel_flowlist, flowchain); 412 } 413 /* start again */ 414 continue; 415 } 416 417 /* we have a packet to return, 418 * update flow deficit and return the packet*/ 419 f->deficit -= mbuf->m_pkthdr.len; 420 return mbuf; 421 422 } while (1); 423 424 /* unreachable point */ 425 return NULL; 426 } 427 428 /* 429 * Initialize fq_codel scheduler instance. 430 * also, allocate memory for flows array. 431 */ 432 static int 433 fq_codel_new_sched(struct dn_sch_inst *_si) 434 { 435 struct fq_codel_si *si; 436 struct dn_queue *q; 437 struct fq_codel_schk *schk; 438 int i; 439 440 si = (struct fq_codel_si *)_si; 441 schk = (struct fq_codel_schk *)(_si->sched+1); 442 443 if(si->flows) { 444 D("si already configured!"); 445 return 0; 446 } 447 448 /* init the main queue */ 449 q = &si->main_q; 450 set_oid(&q->ni.oid, DN_QUEUE, sizeof(*q)); 451 q->_si = _si; 452 q->fs = _si->sched->fs; 453 454 /* allocate memory for flows array */ 455 si->flows = mallocarray(schk->cfg.flows_cnt, 456 sizeof(struct fq_codel_flow), M_DUMMYNET, M_NOWAIT | M_ZERO); 457 if (si->flows == NULL) { 458 D("cannot allocate memory for fq_codel configuration parameters"); 459 return ENOMEM ; 460 } 461 462 /* init perturbation for this si */ 463 si->perturbation = random(); 464 465 /* init the old and new flows lists */ 466 STAILQ_INIT(&si->newflows); 467 STAILQ_INIT(&si->oldflows); 468 469 /* init the flows (sub-queues) */ 470 for (i = 0; i < schk->cfg.flows_cnt; i++) { 471 /* init codel */ 472 si->flows[i].cst.maxpkt_size = 500; 473 } 474 475 fq_codel_desc.ref_count++; 476 return 0; 477 } 478 479 /* 480 * Free fq_codel scheduler instance. 481 */ 482 static int 483 fq_codel_free_sched(struct dn_sch_inst *_si) 484 { 485 struct fq_codel_si *si = (struct fq_codel_si *)_si ; 486 487 /* free the flows array */ 488 free(si->flows , M_DUMMYNET); 489 si->flows = NULL; 490 fq_codel_desc.ref_count--; 491 492 return 0; 493 } 494 495 /* 496 * Configure fq_codel scheduler. 497 * the configurations for the scheduler is passed from userland. 498 */ 499 static int 500 fq_codel_config(struct dn_schk *_schk) 501 { 502 struct fq_codel_schk *schk; 503 struct dn_extra_parms *ep; 504 struct dn_sch_fq_codel_parms *fqc_cfg; 505 506 schk = (struct fq_codel_schk *)(_schk+1); 507 ep = (struct dn_extra_parms *) _schk->cfg; 508 509 /* par array contains fq_codel configuration as follow 510 * Codel: 0- target,1- interval, 2- flags 511 * FQ_CODEL: 3- quantum, 4- limit, 5- flows 512 */ 513 if (ep && ep->oid.len ==sizeof(*ep) && 514 ep->oid.subtype == DN_SCH_PARAMS) { 515 fqc_cfg = &schk->cfg; 516 if (ep->par[0] < 0) 517 fqc_cfg->ccfg.target = fq_codel_sysctl.ccfg.target; 518 else 519 fqc_cfg->ccfg.target = ep->par[0] * AQM_TIME_1US; 520 521 if (ep->par[1] < 0) 522 fqc_cfg->ccfg.interval = fq_codel_sysctl.ccfg.interval; 523 else 524 fqc_cfg->ccfg.interval = ep->par[1] * AQM_TIME_1US; 525 526 if (ep->par[2] < 0) 527 fqc_cfg->ccfg.flags = 0; 528 else 529 fqc_cfg->ccfg.flags = ep->par[2]; 530 531 /* FQ configurations */ 532 if (ep->par[3] < 0) 533 fqc_cfg->quantum = fq_codel_sysctl.quantum; 534 else 535 fqc_cfg->quantum = ep->par[3]; 536 537 if (ep->par[4] < 0) 538 fqc_cfg->limit = fq_codel_sysctl.limit; 539 else 540 fqc_cfg->limit = ep->par[4]; 541 542 if (ep->par[5] < 0) 543 fqc_cfg->flows_cnt = fq_codel_sysctl.flows_cnt; 544 else 545 fqc_cfg->flows_cnt = ep->par[5]; 546 547 /* Bound the configurations */ 548 fqc_cfg->ccfg.target = BOUND_VAR(fqc_cfg->ccfg.target, 1 , 549 5 * AQM_TIME_1S); ; 550 fqc_cfg->ccfg.interval = BOUND_VAR(fqc_cfg->ccfg.interval, 1, 551 100 * AQM_TIME_1S); 552 553 fqc_cfg->quantum = BOUND_VAR(fqc_cfg->quantum,1, 9000); 554 fqc_cfg->limit= BOUND_VAR(fqc_cfg->limit,1,20480); 555 fqc_cfg->flows_cnt= BOUND_VAR(fqc_cfg->flows_cnt,1,65536); 556 } 557 else 558 return 1; 559 560 return 0; 561 } 562 563 /* 564 * Return fq_codel scheduler configurations 565 * the configurations for the scheduler is passed to userland. 566 */ 567 static int 568 fq_codel_getconfig (struct dn_schk *_schk, struct dn_extra_parms *ep) { 569 struct fq_codel_schk *schk = (struct fq_codel_schk *)(_schk+1); 570 struct dn_sch_fq_codel_parms *fqc_cfg; 571 572 fqc_cfg = &schk->cfg; 573 574 strcpy(ep->name, fq_codel_desc.name); 575 ep->par[0] = fqc_cfg->ccfg.target / AQM_TIME_1US; 576 ep->par[1] = fqc_cfg->ccfg.interval / AQM_TIME_1US; 577 ep->par[2] = fqc_cfg->ccfg.flags; 578 579 ep->par[3] = fqc_cfg->quantum; 580 ep->par[4] = fqc_cfg->limit; 581 ep->par[5] = fqc_cfg->flows_cnt; 582 583 return 0; 584 } 585 586 /* 587 * fq_codel scheduler descriptor 588 * contains the type of the scheduler, the name, the size of extra 589 * data structures, and function pointers. 590 */ 591 static struct dn_alg fq_codel_desc = { 592 _SI( .type = ) DN_SCHED_FQ_CODEL, 593 _SI( .name = ) "FQ_CODEL", 594 _SI( .flags = ) 0, 595 596 _SI( .schk_datalen = ) sizeof(struct fq_codel_schk), 597 _SI( .si_datalen = ) sizeof(struct fq_codel_si) - sizeof(struct dn_sch_inst), 598 _SI( .q_datalen = ) 0, 599 600 _SI( .enqueue = ) fq_codel_enqueue, 601 _SI( .dequeue = ) fq_codel_dequeue, 602 _SI( .config = ) fq_codel_config, /* new sched i.e. sched X config ...*/ 603 _SI( .destroy = ) NULL, /*sched x delete */ 604 _SI( .new_sched = ) fq_codel_new_sched, /* new schd instance */ 605 _SI( .free_sched = ) fq_codel_free_sched, /* delete schd instance */ 606 _SI( .new_fsk = ) NULL, 607 _SI( .free_fsk = ) NULL, 608 _SI( .new_queue = ) NULL, 609 _SI( .free_queue = ) NULL, 610 _SI( .getconfig = ) fq_codel_getconfig, 611 _SI( .ref_count = ) 0 612 }; 613 614 DECLARE_DNSCHED_MODULE(dn_fq_codel, &fq_codel_desc); 615