ng_car.c revision 169602
1/*- 2 * Copyright (c) 2005 Nuno Antunes <nuno.antunes@gmail.com> 3 * Copyright (c) 2007 Alexander Motin <mav@freebsd.org> 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 * 27 * $FreeBSD: head/sys/netgraph/ng_car.c 169602 2007-05-16 12:11:09Z mav $ 28 */ 29 30/* 31 * ng_car - An implementation of commited access rate for netgraph 32 * 33 * TODO: 34 * - Sanitize input config values (impose some limits) 35 * - Implement internal packet painting (possibly using mbuf tags) 36 * - Implement color-aware mode 37 * - Implement DSCP marking for IPv4 38 */ 39 40#include <sys/param.h> 41#include <sys/errno.h> 42#include <sys/kernel.h> 43#include <sys/malloc.h> 44#include <sys/mbuf.h> 45 46#include <netgraph/ng_message.h> 47#include <netgraph/ng_parse.h> 48#include <netgraph/netgraph.h> 49#include <netgraph/ng_car.h> 50 51#define NG_CAR_QUEUE_SIZE 100 /* Maximum queue size for SHAPE mode */ 52#define NG_CAR_QUEUE_MIN_TH 8 /* Minimum RED threshhold for SHAPE mode */ 53 54/* Hook private info */ 55struct hookinfo { 56 hook_p hook; /* this (source) hook */ 57 hook_p dest; /* destination hook */ 58 59 int64_t tc; /* commited token bucket counter */ 60 int64_t te; /* exceeded/peak token bucket counter */ 61 struct timeval lastRefill; /* last token refill time */ 62 63 struct ng_car_hookconf conf; /* hook configuration */ 64 struct ng_car_hookstats stats; /* hook stats */ 65 66 struct mbuf *q[NG_CAR_QUEUE_SIZE]; /* circular packet queue */ 67 int q_first; /* first queue element */ 68 int q_last; /* last queue element */ 69 struct callout q_callout; /* periodic queue processing routine */ 70 struct mtx q_mtx; /* queue mutex */ 71}; 72 73/* Private information for each node instance */ 74struct privdata { 75 node_p node; /* the node itself */ 76 struct hookinfo upper; /* hook to upper layers */ 77 struct hookinfo lower; /* hook to lower layers */ 78}; 79typedef struct privdata *priv_p; 80 81static ng_constructor_t ng_car_constructor; 82static ng_rcvmsg_t ng_car_rcvmsg; 83static ng_shutdown_t ng_car_shutdown; 84static ng_newhook_t ng_car_newhook; 85static ng_rcvdata_t ng_car_rcvdata; 86static ng_disconnect_t ng_car_disconnect; 87 88static void ng_car_refillhook(struct hookinfo *h); 89static void ng_car_schedule(struct hookinfo *h); 90void ng_car_q_event(node_p node, hook_p hook, void *arg, int arg2); 91static void ng_car_enqueue(struct hookinfo *h, item_p item); 92 93/* Parse type for struct ng_car_hookstats */ 94static const struct ng_parse_struct_field ng_car_hookstats_type_fields[] 95 = NG_CAR_HOOKSTATS; 96static const struct ng_parse_type ng_car_hookstats_type = { 97 &ng_parse_struct_type, 98 &ng_car_hookstats_type_fields 99}; 100 101/* Parse type for struct ng_car_bulkstats */ 102static const struct ng_parse_struct_field ng_car_bulkstats_type_fields[] 103 = NG_CAR_BULKSTATS(&ng_car_hookstats_type); 104static const struct ng_parse_type ng_car_bulkstats_type = { 105 &ng_parse_struct_type, 106 &ng_car_bulkstats_type_fields 107}; 108 109/* Parse type for struct ng_car_hookconf */ 110static const struct ng_parse_struct_field ng_car_hookconf_type_fields[] 111 = NG_CAR_HOOKCONF; 112static const struct ng_parse_type ng_car_hookconf_type = { 113 &ng_parse_struct_type, 114 &ng_car_hookconf_type_fields 115}; 116 117/* Parse type for struct ng_car_bulkconf */ 118static const struct ng_parse_struct_field ng_car_bulkconf_type_fields[] 119 = NG_CAR_BULKCONF(&ng_car_hookconf_type); 120static const struct ng_parse_type ng_car_bulkconf_type = { 121 &ng_parse_struct_type, 122 &ng_car_bulkconf_type_fields 123}; 124 125/* Command list */ 126static struct ng_cmdlist ng_car_cmdlist[] = { 127 { 128 NGM_CAR_COOKIE, 129 NGM_CAR_GET_STATS, 130 "getstats", 131 NULL, 132 &ng_car_bulkstats_type, 133 }, 134 { 135 NGM_CAR_COOKIE, 136 NGM_CAR_CLR_STATS, 137 "clrstats", 138 NULL, 139 NULL, 140 }, 141 { 142 NGM_CAR_COOKIE, 143 NGM_CAR_GETCLR_STATS, 144 "getclrstats", 145 NULL, 146 &ng_car_bulkstats_type, 147 }, 148 149 { 150 NGM_CAR_COOKIE, 151 NGM_CAR_GET_CONF, 152 "getconf", 153 NULL, 154 &ng_car_bulkconf_type, 155 }, 156 { 157 NGM_CAR_COOKIE, 158 NGM_CAR_SET_CONF, 159 "setconf", 160 &ng_car_bulkconf_type, 161 NULL, 162 }, 163 { 0 } 164}; 165 166/* Netgraph node type descriptor */ 167static struct ng_type ng_car_typestruct = { 168 .version = NG_ABI_VERSION, 169 .name = NG_CAR_NODE_TYPE, 170 .constructor = ng_car_constructor, 171 .rcvmsg = ng_car_rcvmsg, 172 .shutdown = ng_car_shutdown, 173 .newhook = ng_car_newhook, 174 .rcvdata = ng_car_rcvdata, 175 .disconnect = ng_car_disconnect, 176 .cmdlist = ng_car_cmdlist, 177}; 178NETGRAPH_INIT(car, &ng_car_typestruct); 179 180/* 181 * Node constructor 182 */ 183static int 184ng_car_constructor(node_p node) 185{ 186 priv_p priv; 187 188 /* Initialize private descriptor. */ 189 priv = malloc(sizeof(*priv), M_NETGRAPH, M_NOWAIT | M_ZERO); 190 if (priv == NULL) 191 return (ENOMEM); 192 193 NG_NODE_SET_PRIVATE(node, priv); 194 priv->node = node; 195 196 /* 197 * Arbitrary default values 198 */ 199 200 priv->upper.hook = NULL; 201 priv->upper.dest = NULL; 202 priv->upper.tc = priv->upper.conf.cbs = NG_CAR_CBS_MIN; 203 priv->upper.te = priv->upper.conf.ebs = NG_CAR_EBS_MIN; 204 priv->upper.conf.cir = NG_CAR_CIR_DFLT; 205 priv->upper.conf.green_action = NG_CAR_ACTION_FORWARD; 206 priv->upper.conf.yellow_action = NG_CAR_ACTION_FORWARD; 207 priv->upper.conf.red_action = NG_CAR_ACTION_DROP; 208 priv->upper.conf.mode = 0; 209 getmicrotime(&priv->upper.lastRefill); 210 priv->upper.q_first = 0; 211 priv->upper.q_last = 0; 212 ng_callout_init(&priv->upper.q_callout); 213 mtx_init(&priv->upper.q_mtx, "ng_car_u", NULL, MTX_DEF); 214 215 priv->lower.hook = NULL; 216 priv->lower.dest = NULL; 217 priv->lower.tc = priv->lower.conf.cbs = NG_CAR_CBS_MIN; 218 priv->lower.te = priv->lower.conf.ebs = NG_CAR_EBS_MIN; 219 priv->lower.conf.cir = NG_CAR_CIR_DFLT; 220 priv->lower.conf.green_action = NG_CAR_ACTION_FORWARD; 221 priv->lower.conf.yellow_action = NG_CAR_ACTION_FORWARD; 222 priv->lower.conf.red_action = NG_CAR_ACTION_DROP; 223 priv->lower.conf.mode = 0; 224 priv->lower.lastRefill = priv->upper.lastRefill; 225 priv->lower.q_first = 0; 226 priv->lower.q_last = 0; 227 ng_callout_init(&priv->lower.q_callout); 228 mtx_init(&priv->lower.q_mtx, "ng_car_l", NULL, MTX_DEF); 229 230 return (0); 231} 232 233/* 234 * Add a hook. 235 */ 236static int 237ng_car_newhook(node_p node, hook_p hook, const char *name) 238{ 239 const priv_p priv = NG_NODE_PRIVATE(node); 240 241 if (strcmp(name, NG_CAR_HOOK_LOWER) == 0) { 242 priv->lower.hook = hook; 243 priv->upper.dest = hook; 244 bzero(&priv->lower.stats, sizeof(priv->lower.stats)); 245 NG_HOOK_SET_PRIVATE(hook, &priv->lower); 246 } else if (strcmp(name, NG_CAR_HOOK_UPPER) == 0) { 247 priv->upper.hook = hook; 248 priv->lower.dest = hook; 249 bzero(&priv->upper.stats, sizeof(priv->upper.stats)); 250 NG_HOOK_SET_PRIVATE(hook, &priv->upper); 251 } else 252 return (EINVAL); 253 return(0); 254} 255 256/* 257 * Data has arrived. 258 */ 259static int 260ng_car_rcvdata(hook_p hook, item_p item ) 261{ 262 struct hookinfo *const hinfo = NG_HOOK_PRIVATE(hook); 263 hook_p dest = hinfo->dest; 264 struct mbuf *m = NULL; 265 int error = 0; 266 267 /* Node is useless without destination hook. */ 268 if (dest == NULL) { 269 NG_FREE_ITEM(item); 270 ++hinfo->stats.errors; 271 return(EINVAL); 272 } 273 274 /* If queue is not empty now then enqueue packet. */ 275 if (hinfo->q_first != hinfo->q_last) { 276 ng_car_enqueue(hinfo, item); 277 return (0); 278 } 279 280 m = NGI_M(item); 281 282#define NG_CAR_PERFORM_MATCH_ACTION(a) \ 283 do { \ 284 switch (a) { \ 285 case NG_CAR_ACTION_FORWARD: \ 286 /* Do nothing. */ \ 287 break; \ 288 case NG_CAR_ACTION_MARK: \ 289 /* XXX find a way to mark packets (mbuf tag?) */ \ 290 ++hinfo->stats.errors; \ 291 break; \ 292 case NG_CAR_ACTION_DROP: \ 293 default: \ 294 /* Drop packet and return. */ \ 295 NG_FREE_ITEM(item); \ 296 ++hinfo->stats.droped_pkts; \ 297 return (0); \ 298 } \ 299 } while (0) 300 301 /* Check commited token bucket. */ 302 if (hinfo->tc - m->m_pkthdr.len >= 0) { 303 /* This packet is green. */ 304 ++hinfo->stats.green_pkts; 305 hinfo->tc -= m->m_pkthdr.len; 306 NG_CAR_PERFORM_MATCH_ACTION(hinfo->conf.green_action); 307 } else { 308 309 /* Refill only if not green without it. */ 310 ng_car_refillhook(hinfo); 311 312 /* Check commited token bucket again after refill. */ 313 if (hinfo->tc - m->m_pkthdr.len >= 0) { 314 /* This packet is green */ 315 ++hinfo->stats.green_pkts; 316 hinfo->tc -= m->m_pkthdr.len; 317 NG_CAR_PERFORM_MATCH_ACTION(hinfo->conf.green_action); 318 319 /* If not green and mode is SHAPE, enqueue packet. */ 320 } else if (hinfo->conf.mode == NG_CAR_SHAPE) { 321 ng_car_enqueue(hinfo, item); 322 return (0); 323 324 /* If not green and mode is RED, calculate probability. */ 325 } else if (hinfo->conf.mode == NG_CAR_RED) { 326 /* Is packet is bigger then extended burst? */ 327 if (m->m_pkthdr.len - (hinfo->tc - m->m_pkthdr.len) > 328 hinfo->conf.ebs) { 329 /* This packet is definitely red. */ 330 ++hinfo->stats.red_pkts; 331 hinfo->te = 0; 332 NG_CAR_PERFORM_MATCH_ACTION(hinfo->conf.red_action); 333 334 /* Use token bucket to simulate RED-like drop 335 probability. */ 336 } else if (hinfo->te + (m->m_pkthdr.len - hinfo->tc) < 337 hinfo->conf.ebs) { 338 /* This packet is yellow */ 339 ++hinfo->stats.yellow_pkts; 340 hinfo->te += m->m_pkthdr.len - hinfo->tc; 341 /* Go to negative tokens. */ 342 hinfo->tc -= m->m_pkthdr.len; 343 NG_CAR_PERFORM_MATCH_ACTION(hinfo->conf.yellow_action); 344 } else { 345 /* This packet is probaly red. */ 346 ++hinfo->stats.red_pkts; 347 hinfo->te = 0; 348 NG_CAR_PERFORM_MATCH_ACTION(hinfo->conf.red_action); 349 } 350 /* If not green and mode is SINGLE/DOUBLE RATE. */ 351 } else { 352 /* Check extended token bucket. */ 353 if (hinfo->te - m->m_pkthdr.len >= 0) { 354 /* This packet is yellow */ 355 ++hinfo->stats.yellow_pkts; 356 hinfo->te -= m->m_pkthdr.len; 357 NG_CAR_PERFORM_MATCH_ACTION(hinfo->conf.yellow_action); 358 } else { 359 /* This packet is red */ 360 ++hinfo->stats.red_pkts; 361 NG_CAR_PERFORM_MATCH_ACTION(hinfo->conf.red_action); 362 } 363 } 364 } 365 366#undef NG_CAR_PERFORM_MATCH_ACTION 367 368 NG_FWD_ITEM_HOOK(error, item, dest); 369 if (error != 0) 370 ++hinfo->stats.errors; 371 ++hinfo->stats.passed_pkts; 372 373 return (error); 374} 375 376/* 377 * Receive a control message. 378 */ 379static int 380ng_car_rcvmsg(node_p node, item_p item, hook_p lasthook) 381{ 382 const priv_p priv = NG_NODE_PRIVATE(node); 383 struct ng_mesg *resp = NULL; 384 int error = 0; 385 struct ng_mesg *msg; 386 387 NGI_GET_MSG(item, msg); 388 switch (msg->header.typecookie) { 389 case NGM_CAR_COOKIE: 390 switch (msg->header.cmd) { 391 case NGM_CAR_GET_STATS: 392 case NGM_CAR_GETCLR_STATS: 393 { 394 struct ng_car_bulkstats *bstats; 395 396 NG_MKRESPONSE(resp, msg, 397 sizeof(*bstats), M_NOWAIT); 398 if (resp == NULL) { 399 error = ENOMEM; 400 break; 401 } 402 bstats = (struct ng_car_bulkstats *)resp->data; 403 404 bcopy(&priv->upper.stats, &bstats->downstream, 405 sizeof(bstats->downstream)); 406 bcopy(&priv->lower.stats, &bstats->upstream, 407 sizeof(bstats->upstream)); 408 } 409 if (msg->header.cmd == NGM_CAR_GET_STATS) 410 break; 411 case NGM_CAR_CLR_STATS: 412 bzero(&priv->upper.stats, 413 sizeof(priv->upper.stats)); 414 bzero(&priv->lower.stats, 415 sizeof(priv->lower.stats)); 416 break; 417 case NGM_CAR_GET_CONF: 418 { 419 struct ng_car_bulkconf *bconf; 420 421 NG_MKRESPONSE(resp, msg, 422 sizeof(*bconf), M_NOWAIT); 423 if (resp == NULL) { 424 error = ENOMEM; 425 break; 426 } 427 bconf = (struct ng_car_bulkconf *)resp->data; 428 429 bcopy(&priv->upper.conf, &bconf->downstream, 430 sizeof(bconf->downstream)); 431 bcopy(&priv->lower.conf, &bconf->upstream, 432 sizeof(bconf->upstream)); 433 } 434 break; 435 case NGM_CAR_SET_CONF: 436 { 437 struct ng_car_bulkconf *const bconf = 438 (struct ng_car_bulkconf *)msg->data; 439 440 /* Check for invalid or illegal config. */ 441 if ((msg->header.arglen != sizeof(*bconf)) 442 || (bconf->downstream.cir > 1000000000) 443 || (bconf->downstream.pir > 1000000000) 444 || (bconf->upstream.cir > 1000000000) 445 || (bconf->upstream.pir > 1000000000) 446 || (bconf->downstream.cbs == 0 447 && bconf->downstream.ebs == 0) 448 || (bconf->upstream.cbs == 0 449 && bconf->upstream.ebs == 0)) 450 { 451 error = EINVAL; 452 break; 453 } 454 455 /* Copy downstream config. */ 456 bcopy(&bconf->downstream, &priv->upper.conf, 457 sizeof(priv->upper.conf)); 458 priv->upper.tc = priv->upper.conf.cbs; 459 if (priv->upper.conf.mode == NG_CAR_RED || 460 priv->lower.conf.mode == NG_CAR_SHAPE) { 461 priv->upper.te = 0; 462 } else { 463 priv->upper.te = priv->upper.conf.ebs; 464 } 465 466 /* Copy upstream config. */ 467 bcopy(&bconf->upstream, &priv->lower.conf, 468 sizeof(priv->lower.conf)); 469 priv->lower.tc = priv->lower.conf.cbs; 470 if (priv->lower.conf.mode == NG_CAR_RED || 471 priv->lower.conf.mode == NG_CAR_SHAPE) { 472 priv->lower.te = 0; 473 } else { 474 priv->lower.te = priv->lower.conf.ebs; 475 } 476 } 477 break; 478 default: 479 error = EINVAL; 480 break; 481 } 482 break; 483 default: 484 error = EINVAL; 485 break; 486 } 487 NG_RESPOND_MSG(error, node, item, resp); 488 NG_FREE_MSG(msg); 489 return (error); 490} 491 492/* 493 * Do local shutdown processing. 494 */ 495static int 496ng_car_shutdown(node_p node) 497{ 498 const priv_p priv = NG_NODE_PRIVATE(node); 499 500 mtx_destroy(&priv->upper.q_mtx); 501 mtx_destroy(&priv->lower.q_mtx); 502 NG_NODE_UNREF(priv->node); 503 free(priv, M_NETGRAPH); 504 return (0); 505} 506 507/* 508 * Hook disconnection. 509 * 510 * For this type, removal of the last link destroys the node. 511 */ 512static int 513ng_car_disconnect(hook_p hook) 514{ 515 struct hookinfo *const hinfo = NG_HOOK_PRIVATE(hook); 516 const node_p node = NG_HOOK_NODE(hook); 517 const priv_p priv = NG_NODE_PRIVATE(node); 518 519 if (hinfo) { 520 /* Purge queue if not empty. */ 521 while (hinfo->q_first != hinfo->q_last) { 522 NG_FREE_M(hinfo->q[hinfo->q_first]); 523 hinfo->q_first++; 524 if (hinfo->q_first >= NG_CAR_QUEUE_SIZE) 525 hinfo->q_first = 0; 526 } 527 /* Remove hook refs. */ 528 if (hinfo->hook == priv->upper.hook) 529 priv->lower.dest = NULL; 530 else 531 priv->upper.dest = NULL; 532 hinfo->hook = NULL; 533 } 534 /* Already shutting down? */ 535 if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0) 536 && (NG_NODE_IS_VALID(NG_HOOK_NODE(hook)))) 537 ng_rmnode_self(NG_HOOK_NODE(hook)); 538 return (0); 539} 540 541/* 542 * Hook's token buckets refillment. 543 */ 544static void 545ng_car_refillhook(struct hookinfo *h) 546{ 547 struct timeval newt, deltat; 548 int64_t deltat_us; 549 int64_t delta; 550 551 /* Get current time. */ 552 getmicrotime(&newt); 553 554 /* Time must go forward. */ 555 if (timevalcmp(&newt, &h->lastRefill, <= )) { 556 h->lastRefill = newt; 557 return; 558 } 559 560 /* Get time delta since last refill. */ 561 deltat = newt; 562 timevalsub(&deltat, &h->lastRefill); 563 564 /* Sanity check */ 565 if (deltat.tv_sec > 1000) { 566 deltat_us = 1000000000; 567 } else { 568 deltat_us = ((int64_t)deltat.tv_sec) * 1000000 + deltat.tv_usec; 569 } 570 571 if (h->conf.mode == NG_CAR_SINGLE_RATE) { 572 /* Refill commited token bucket. */ 573 h->tc += h->conf.cir * deltat_us / 8000000; 574 delta = h->tc - h->conf.cbs; 575 if (delta > 0) { 576 h->tc = h->conf.cbs; 577 578 /* Refill exceeded token bucket. */ 579 h->te += delta; 580 if (h->te > h->conf.ebs) 581 h->te = h->conf.ebs; 582 } 583 584 } else if (h->conf.mode == NG_CAR_DOUBLE_RATE) { 585 /* Refill commited token bucket. */ 586 h->tc += h->conf.cir * deltat_us / 8000000; 587 if (h->tc > h->conf.cbs) 588 h->tc = h->conf.cbs; 589 590 /* Refill peak token bucket. */ 591 h->te += h->conf.pir * deltat_us / 8000000; 592 if (h->te > h->conf.ebs) 593 h->te = h->conf.ebs; 594 595 } else { /* RED or SHAPE mode. */ 596 /* Refill commited token bucket. */ 597 h->tc += h->conf.cir * deltat_us / 8000000; 598 if (h->tc > ((int64_t)h->conf.cbs)) 599 h->tc = h->conf.cbs; 600 } 601 602 /* Remember this moment. */ 603 h->lastRefill = newt; 604} 605 606/* 607 * Schedule callout when we will have required tokens. 608 */ 609static void 610ng_car_schedule(struct hookinfo *hinfo) 611{ 612 int delay; 613 614 delay = (-(hinfo->tc)) * hz * 8 / hinfo->conf.cir + 1; 615 616 ng_callout(&hinfo->q_callout, NG_HOOK_NODE(hinfo->hook), hinfo->hook, 617 delay, &ng_car_q_event, NULL, 0); 618} 619 620/* 621 * Queue processing callout handler. 622 */ 623void 624ng_car_q_event(node_p node, hook_p hook, void *arg, int arg2) 625{ 626 struct hookinfo *hinfo = NG_HOOK_PRIVATE(hook); 627 item_p item; 628 struct mbuf *m; 629 int error; 630 631 /* Refill tokens for time we have slept. */ 632 ng_car_refillhook(hinfo); 633 634 if (hinfo->dest != NULL) { 635 /* If we have some tokens */ 636 while (hinfo->tc >= 0) { 637 638 /* Send packet. */ 639 m = hinfo->q[hinfo->q_first]; 640 if ((item = ng_package_data(m, NG_NOFLAGS)) != NULL) 641 NG_FWD_ITEM_HOOK(error, item, hinfo->dest); 642 643 /* Get next one. */ 644 hinfo->q_first++; 645 if (hinfo->q_first >= NG_CAR_QUEUE_SIZE) 646 hinfo->q_first = 0; 647 648 /* Stop if none left. */ 649 if (hinfo->q_first == hinfo->q_last) 650 break; 651 652 /* If we have more packet, try it. */ 653 m = hinfo->q[hinfo->q_first]; 654 hinfo->tc -= m->m_pkthdr.len; 655 } 656 } 657 658 /* If something left */ 659 if (hinfo->q_first != hinfo->q_last) 660 /* Schedule queue processing. */ 661 ng_car_schedule(hinfo); 662} 663 664/* 665 * Enqueue packet. 666 */ 667static void 668ng_car_enqueue(struct hookinfo *hinfo, item_p item) 669{ 670 struct mbuf *m; 671 int len; 672 673 NGI_GET_M(item, m); 674 NG_FREE_ITEM(item); 675 676 /* Lock queue mutex. */ 677 mtx_lock(&hinfo->q_mtx); 678 679 /* Calculate used queue length. */ 680 len = hinfo->q_last - hinfo->q_first; 681 if (len < 0) 682 len += NG_CAR_QUEUE_SIZE; 683 684 /* If queue is overflowed or we have no RED tokens. */ 685 if ((len >= (NG_CAR_QUEUE_SIZE - 1)) || 686 (hinfo->te + len >= NG_CAR_QUEUE_SIZE)) { 687 /* Drop packet. */ 688 ++hinfo->stats.red_pkts; 689 NG_FREE_M(m); 690 691 hinfo->te = 0; 692 } else { 693 /* This packet is yellow. */ 694 ++hinfo->stats.yellow_pkts; 695 696 /* Enqueue packet. */ 697 hinfo->q[hinfo->q_last] = m; 698 hinfo->q_last++; 699 if (hinfo->q_last >= NG_CAR_QUEUE_SIZE) 700 hinfo->q_last = 0; 701 702 /* Use RED tokens. */ 703 if (len > NG_CAR_QUEUE_MIN_TH) 704 hinfo->te += len - NG_CAR_QUEUE_MIN_TH; 705 706 /* If this is a first packet in the queue. */ 707 if (len == 0) { 708 hinfo->tc -= m->m_pkthdr.len; 709 710 /* Schedule queue processing. */ 711 ng_car_schedule(hinfo); 712 } 713 } 714 715 /* Unlock queue mutex. */ 716 mtx_unlock(&hinfo->q_mtx); 717} 718