sys/net/altq/altq_subr.c

   1 /*      $KAME: altq_subr.c,v 1.23 2004/04/20 16:10:06 itojun Exp $      */
   2 /*      $DragonFly: src/sys/net/altq/altq_subr.c,v 1.9 2006/12/23 00:44:55 swildner Exp $ */
   3
   4 /*
   5  * Copyright (C) 1997-2003
   6  *      Sony Computer Science Laboratories Inc.  All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY SONY CSL AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL SONY CSL OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  */
  29
  30 #include "opt_altq.h"
  31 #include "opt_inet.h"
  32 #include "opt_inet6.h"
  33
  34 #include <sys/param.h>
  35 #include <sys/malloc.h>
  36 #include <sys/mbuf.h>
  37 #include <sys/systm.h>
  38 #include <sys/proc.h>
  39 #include <sys/socket.h>
  40 #include <sys/socketvar.h>
  41 #include <sys/kernel.h>
  42 #include <sys/callout.h>
  43 #include <sys/errno.h>
  44 #include <sys/syslog.h>
  45 #include <sys/sysctl.h>
  46 #include <sys/queue.h>
  47 #include <sys/thread2.h>
  48
  49 #include <net/if.h>
  50 #include <net/if_dl.h>
  51 #include <net/if_types.h>
  52 #include <net/ifq_var.h>
  53
  54 #include <netinet/in.h>
  55 #include <netinet/in_systm.h>
  56 #include <netinet/ip.h>
  57 #ifdef INET6
  58 #include <netinet/ip6.h>
  59 #endif
  60 #include <netinet/tcp.h>
  61 #include <netinet/udp.h>
  62
  63 #include <net/pf/pfvar.h>
  64 #include <net/altq/altq.h>
  65
  66 /* machine dependent clock related includes */
  67 #if defined(__i386__)
  68 #include <machine/clock.h>              /* for tsc_freq */
  69 #include <machine/md_var.h>             /* for cpu_feature */
  70 #include <machine/specialreg.h>         /* for CPUID_TSC */
  71 #endif /* __i386__ */
  72
  73 /*
  74  * internal function prototypes
  75  */
  76 static void     tbr_timeout(void *);
  77 int (*altq_input)(struct mbuf *, int) = NULL;
  78 static int tbr_timer = 0;       /* token bucket regulator timer */
  79 static struct callout tbr_callout;
  80
  81 int pfaltq_running;     /* keep track of running state */
  82
  83 MALLOC_DEFINE(M_ALTQ, "altq", "ALTQ structures");
  84
  85 /*
  86  * alternate queueing support routines
  87  */
  88
  89 /* look up the queue state by the interface name and the queueing type. */
  90 void *
  91 altq_lookup(const char *name, int type)
  92 {
  93         struct ifnet *ifp;
  94
  95         if ((ifp = ifunit(name)) != NULL) {
  96                 if (type != ALTQT_NONE && ifp->if_snd.altq_type == type)
  97                         return (ifp->if_snd.altq_disc);
  98         }
  99
 100         return (NULL);
 101 }
 102
 103 int
 104 altq_attach(struct ifaltq *ifq, int type, void *discipline,
 105             int (*enqueue)(struct ifaltq *, struct mbuf *, struct altq_pktattr *),
 106             struct mbuf *(*dequeue)(struct ifaltq *, struct mbuf *, int),
 107             int (*request)(struct ifaltq *, int, void *),
 108             void *clfier,
 109             void *(*classify)(struct ifaltq *, struct mbuf *,
 110                               struct altq_pktattr *))
 111 {
 112         if (!ifq_is_ready(ifq))
 113                 return ENXIO;
 114
 115         ifq->altq_type     = type;
 116         ifq->altq_disc     = discipline;
 117         ifq->altq_enqueue  = enqueue;
 118         ifq->altq_dequeue  = dequeue;
 119         ifq->altq_request  = request;
 120         ifq->altq_clfier   = clfier;
 121         ifq->altq_classify = classify;
 122         ifq->altq_flags &= (ALTQF_CANTCHANGE|ALTQF_ENABLED);
 123         return 0;
 124 }
 125
 126 int
 127 altq_detach(struct ifaltq *ifq)
 128 {
 129         if (!ifq_is_ready(ifq))
 130                 return ENXIO;
 131         if (ifq_is_enabled(ifq))
 132                 return EBUSY;
 133         if (!ifq_is_attached(ifq))
 134                 return (0);
 135
 136         ifq_set_classic(ifq);
 137         ifq->altq_type     = ALTQT_NONE;
 138         ifq->altq_disc     = NULL;
 139         ifq->altq_clfier   = NULL;
 140         ifq->altq_classify = NULL;
 141         ifq->altq_flags &= ALTQF_CANTCHANGE;
 142         return 0;
 143 }
 144
 145 int
 146 altq_enable(struct ifaltq *ifq)
 147 {
 148         if (!ifq_is_ready(ifq))
 149                 return ENXIO;
 150         if (ifq_is_enabled(ifq))
 151                 return 0;
 152
 153         crit_enter();
 154         ifq_purge(ifq);
 155         KKASSERT(ifq->ifq_len == 0);
 156         ifq->altq_flags |= ALTQF_ENABLED;
 157         if (ifq->altq_clfier != NULL)
 158                 ifq->altq_flags |= ALTQF_CLASSIFY;
 159         crit_exit();
 160
 161         return 0;
 162 }
 163
 164 int
 165 altq_disable(struct ifaltq *ifq)
 166 {
 167         if (!ifq_is_enabled(ifq))
 168                 return 0;
 169
 170         crit_enter();
 171         ifq_purge(ifq);
 172         KKASSERT(ifq->ifq_len == 0);
 173         ifq->altq_flags &= ~(ALTQF_ENABLED|ALTQF_CLASSIFY);
 174         crit_exit();
 175         return 0;
 176 }
 177
 178 /*
 179  * internal representation of token bucket parameters
 180  *      rate:   byte_per_unittime << 32
 181  *              (((bits_per_sec) / 8) << 32) / machclk_freq
 182  *      depth:  byte << 32
 183  *
 184  */
 185 #define TBR_SHIFT       32
 186 #define TBR_SCALE(x)    ((int64_t)(x) << TBR_SHIFT)
 187 #define TBR_UNSCALE(x)  ((x) >> TBR_SHIFT)
 188
 189 struct mbuf *
 190 tbr_dequeue(struct ifaltq *ifq, struct mbuf *mpolled, int op)
 191 {
 192         struct tb_regulator *tbr;
 193         struct mbuf *m;
 194         int64_t interval;
 195         uint64_t now;
 196
 197         crit_enter();
 198         tbr = ifq->altq_tbr;
 199         if (op == ALTDQ_REMOVE && tbr->tbr_lastop == ALTDQ_POLL) {
 200                 /* if this is a remove after poll, bypass tbr check */
 201         } else {
 202                 /* update token only when it is negative */
 203                 if (tbr->tbr_token <= 0) {
 204                         now = read_machclk();
 205                         interval = now - tbr->tbr_last;
 206                         if (interval >= tbr->tbr_filluptime)
 207                                 tbr->tbr_token = tbr->tbr_depth;
 208                         else {
 209                                 tbr->tbr_token += interval * tbr->tbr_rate;
 210                                 if (tbr->tbr_token > tbr->tbr_depth)
 211                                         tbr->tbr_token = tbr->tbr_depth;
 212                         }
 213                         tbr->tbr_last = now;
 214                 }
 215                 /* if token is still negative, don't allow dequeue */
 216                 if (tbr->tbr_token <= 0) {
 217                         crit_exit();
 218                         return (NULL);
 219                 }
 220         }
 221
 222         if (ifq_is_enabled(ifq)) {
 223                 m = (*ifq->altq_dequeue)(ifq, mpolled, op);
 224         } else if (op == ALTDQ_POLL) {
 225                 IF_POLL(ifq, m);
 226         } else {
 227                 IF_DEQUEUE(ifq, m);
 228                 KKASSERT(mpolled == NULL || mpolled == m);
 229         }
 230
 231         if (m != NULL && op == ALTDQ_REMOVE)
 232                 tbr->tbr_token -= TBR_SCALE(m_pktlen(m));
 233         tbr->tbr_lastop = op;
 234         crit_exit();
 235         return (m);
 236 }
 237
 238 /*
 239  * set a token bucket regulator.
 240  * if the specified rate is zero, the token bucket regulator is deleted.
 241  */
 242 int
 243 tbr_set(struct ifaltq *ifq, struct tb_profile *profile)
 244 {
 245         struct tb_regulator *tbr, *otbr;
 246
 247         if (machclk_freq == 0)
 248                 init_machclk();
 249         if (machclk_freq == 0) {
 250                 kprintf("tbr_set: no cpu clock available!\n");
 251                 return (ENXIO);
 252         }
 253
 254         if (profile->rate == 0) {
 255                 /* delete this tbr */
 256                 if ((tbr = ifq->altq_tbr) == NULL)
 257                         return (ENOENT);
 258                 ifq->altq_tbr = NULL;
 259                 kfree(tbr, M_ALTQ);
 260                 return (0);
 261         }
 262
 263         tbr = kmalloc(sizeof(*tbr), M_ALTQ, M_WAITOK | M_ZERO);
 264         tbr->tbr_rate = TBR_SCALE(profile->rate / 8) / machclk_freq;
 265         tbr->tbr_depth = TBR_SCALE(profile->depth);
 266         if (tbr->tbr_rate > 0)
 267                 tbr->tbr_filluptime = tbr->tbr_depth / tbr->tbr_rate;
 268         else
 269                 tbr->tbr_filluptime = 0xffffffffffffffffLL;
 270         tbr->tbr_token = tbr->tbr_depth;
 271         tbr->tbr_last = read_machclk();
 272         tbr->tbr_lastop = ALTDQ_REMOVE;
 273
 274         otbr = ifq->altq_tbr;
 275         ifq->altq_tbr = tbr;    /* set the new tbr */
 276
 277         if (otbr != NULL)
 278                 kfree(otbr, M_ALTQ);
 279         else if (tbr_timer == 0) {
 280                 callout_reset(&tbr_callout, 1, tbr_timeout, NULL);
 281                 tbr_timer = 1;
 282         }
 283         return (0);
 284 }
 285
 286 /*
 287  * tbr_timeout goes through the interface list, and kicks the drivers
 288  * if necessary.
 289  */
 290 static void
 291 tbr_timeout(void *arg)
 292 {
 293         struct ifnet *ifp;
 294         int active;
 295
 296         active = 0;
 297         crit_enter();
 298         for (ifp = TAILQ_FIRST(&ifnet); ifp; ifp = TAILQ_NEXT(ifp, if_list)) {
 299                 if (ifp->if_snd.altq_tbr == NULL)
 300                         continue;
 301                 active++;
 302                 if (!ifq_is_empty(&ifp->if_snd) && ifp->if_start != NULL) {
 303                         lwkt_serialize_enter(ifp->if_serializer);
 304                         (*ifp->if_start)(ifp);
 305                         lwkt_serialize_exit(ifp->if_serializer);
 306                 }
 307         }
 308         crit_exit();
 309         if (active > 0)
 310                 callout_reset(&tbr_callout, 1, tbr_timeout, NULL);
 311         else
 312                 tbr_timer = 0;  /* don't need tbr_timer anymore */
 313 }
 314
 315 /*
 316  * get token bucket regulator profile
 317  */
 318 int
 319 tbr_get(struct ifaltq *ifq, struct tb_profile *profile)
 320 {
 321         struct tb_regulator *tbr;
 322
 323         if ((tbr = ifq->altq_tbr) == NULL) {
 324                 profile->rate = 0;
 325                 profile->depth = 0;
 326         } else {
 327                 profile->rate =
 328                     (u_int)TBR_UNSCALE(tbr->tbr_rate * 8 * machclk_freq);
 329                 profile->depth = (u_int)TBR_UNSCALE(tbr->tbr_depth);
 330         }
 331         return (0);
 332 }
 333
 334 /*
 335  * attach a discipline to the interface.  if one already exists, it is
 336  * overridden.
 337  */
 338 int
 339 altq_pfattach(struct pf_altq *a)
 340 {
 341         struct ifnet *ifp;
 342         struct tb_profile tb;
 343         int error = 0;
 344
 345         switch (a->scheduler) {
 346         case ALTQT_NONE:
 347                 break;
 348 #ifdef ALTQ_CBQ
 349         case ALTQT_CBQ:
 350                 error = cbq_pfattach(a);
 351                 break;
 352 #endif
 353 #ifdef ALTQ_PRIQ
 354         case ALTQT_PRIQ:
 355                 error = priq_pfattach(a);
 356                 break;
 357 #endif
 358 #ifdef ALTQ_HFSC
 359         case ALTQT_HFSC:
 360                 error = hfsc_pfattach(a);
 361                 break;
 362 #endif
 363         default:
 364                 error = ENXIO;
 365         }
 366
 367         ifp = ifunit(a->ifname);
 368
 369         /* if the state is running, enable altq */
 370         if (error == 0 && pfaltq_running &&
 371             ifp != NULL && ifp->if_snd.altq_type != ALTQT_NONE &&
 372             !ifq_is_enabled(&ifp->if_snd))
 373                         error = altq_enable(&ifp->if_snd);
 374
 375         /* if altq is already enabled, reset set tokenbucket regulator */
 376         if (error == 0 && ifp != NULL && ifq_is_enabled(&ifp->if_snd)) {
 377                 tb.rate = a->ifbandwidth;
 378                 tb.depth = a->tbrsize;
 379                 crit_enter();
 380                 error = tbr_set(&ifp->if_snd, &tb);
 381                 crit_exit();
 382         }
 383
 384         return (error);
 385 }
 386
 387 /*
 388  * detach a discipline from the interface.
 389  * it is possible that the discipline was already overridden by another
 390  * discipline.
 391  */
 392 int
 393 altq_pfdetach(struct pf_altq *a)
 394 {
 395         struct ifnet *ifp;
 396         int error = 0;
 397
 398         if ((ifp = ifunit(a->ifname)) == NULL)
 399                 return (EINVAL);
 400
 401         /* if this discipline is no longer referenced, just return */
 402         if (a->altq_disc == NULL || a->altq_disc != ifp->if_snd.altq_disc)
 403                 return (0);
 404
 405         crit_enter();
 406         if (ifq_is_enabled(&ifp->if_snd))
 407                 error = altq_disable(&ifp->if_snd);
 408         if (error == 0)
 409                 error = altq_detach(&ifp->if_snd);
 410         crit_exit();
 411
 412         return (error);
 413 }
 414
 415 /*
 416  * add a discipline or a queue
 417  */
 418 int
 419 altq_add(struct pf_altq *a)
 420 {
 421         int error = 0;
 422
 423         if (a->qname[0] != 0)
 424                 return (altq_add_queue(a));
 425
 426         if (machclk_freq == 0)
 427                 init_machclk();
 428         if (machclk_freq == 0)
 429                 panic("altq_add: no cpu clock");
 430
 431         switch (a->scheduler) {
 432 #ifdef ALTQ_CBQ
 433         case ALTQT_CBQ:
 434                 error = cbq_add_altq(a);
 435                 break;
 436 #endif
 437 #ifdef ALTQ_PRIQ
 438         case ALTQT_PRIQ:
 439                 error = priq_add_altq(a);
 440                 break;
 441 #endif
 442 #ifdef ALTQ_HFSC
 443         case ALTQT_HFSC:
 444                 error = hfsc_add_altq(a);
 445                 break;
 446 #endif
 447         default:
 448                 error = ENXIO;
 449         }
 450
 451         return (error);
 452 }
 453
 454 /*
 455  * remove a discipline or a queue
 456  */
 457 int
 458 altq_remove(struct pf_altq *a)
 459 {
 460         int error = 0;
 461
 462         if (a->qname[0] != 0)
 463                 return (altq_remove_queue(a));
 464
 465         switch (a->scheduler) {
 466 #ifdef ALTQ_CBQ
 467         case ALTQT_CBQ:
 468                 error = cbq_remove_altq(a);
 469                 break;
 470 #endif
 471 #ifdef ALTQ_PRIQ
 472         case ALTQT_PRIQ:
 473                 error = priq_remove_altq(a);
 474                 break;
 475 #endif
 476 #ifdef ALTQ_HFSC
 477         case ALTQT_HFSC:
 478                 error = hfsc_remove_altq(a);
 479                 break;
 480 #endif
 481         default:
 482                 error = ENXIO;
 483         }
 484
 485         return (error);
 486 }
 487
 488 /*
 489  * add a queue to the discipline
 490  */
 491 int
 492 altq_add_queue(struct pf_altq *a)
 493 {
 494         int error = 0;
 495
 496         switch (a->scheduler) {
 497 #ifdef ALTQ_CBQ
 498         case ALTQT_CBQ:
 499                 error = cbq_add_queue(a);
 500                 break;
 501 #endif
 502 #ifdef ALTQ_PRIQ
 503         case ALTQT_PRIQ:
 504                 error = priq_add_queue(a);
 505                 break;
 506 #endif
 507 #ifdef ALTQ_HFSC
 508         case ALTQT_HFSC:
 509                 error = hfsc_add_queue(a);
 510                 break;
 511 #endif
 512         default:
 513                 error = ENXIO;
 514         }
 515
 516         return (error);
 517 }
 518
 519 /*
 520  * remove a queue from the discipline
 521  */
 522 int
 523 altq_remove_queue(struct pf_altq *a)
 524 {
 525         int error = 0;
 526
 527         switch (a->scheduler) {
 528 #ifdef ALTQ_CBQ
 529         case ALTQT_CBQ:
 530                 error = cbq_remove_queue(a);
 531                 break;
 532 #endif
 533 #ifdef ALTQ_PRIQ
 534         case ALTQT_PRIQ:
 535                 error = priq_remove_queue(a);
 536                 break;
 537 #endif
 538 #ifdef ALTQ_HFSC
 539         case ALTQT_HFSC:
 540                 error = hfsc_remove_queue(a);
 541                 break;
 542 #endif
 543         default:
 544                 error = ENXIO;
 545         }
 546
 547         return (error);
 548 }
 549
 550 /*
 551  * get queue statistics
 552  */
 553 int
 554 altq_getqstats(struct pf_altq *a, void *ubuf, int *nbytes)
 555 {
 556         int error = 0;
 557
 558         switch (a->scheduler) {
 559 #ifdef ALTQ_CBQ
 560         case ALTQT_CBQ:
 561                 error = cbq_getqstats(a, ubuf, nbytes);
 562                 break;
 563 #endif
 564 #ifdef ALTQ_PRIQ
 565         case ALTQT_PRIQ:
 566                 error = priq_getqstats(a, ubuf, nbytes);
 567                 break;
 568 #endif
 569 #ifdef ALTQ_HFSC
 570         case ALTQT_HFSC:
 571                 error = hfsc_getqstats(a, ubuf, nbytes);
 572                 break;
 573 #endif
 574         default:
 575                 error = ENXIO;
 576         }
 577
 578         return (error);
 579 }
 580
 581 /*
 582  * read and write diffserv field in IPv4 or IPv6 header
 583  */
 584 uint8_t
 585 read_dsfield(struct mbuf *m, struct altq_pktattr *pktattr)
 586 {
 587         struct mbuf *m0;
 588         uint8_t ds_field = 0;
 589
 590         if (pktattr == NULL ||
 591             (pktattr->pattr_af != AF_INET && pktattr->pattr_af != AF_INET6))
 592                 return ((uint8_t)0);
 593
 594         /* verify that pattr_hdr is within the mbuf data */
 595         for (m0 = m; m0 != NULL; m0 = m0->m_next) {
 596                 if ((pktattr->pattr_hdr >= m0->m_data) &&
 597                     (pktattr->pattr_hdr < m0->m_data + m0->m_len))
 598                         break;
 599         }
 600         if (m0 == NULL) {
 601                 /* ick, pattr_hdr is stale */
 602                 pktattr->pattr_af = AF_UNSPEC;
 603 #ifdef ALTQ_DEBUG
 604                 kprintf("read_dsfield: can't locate header!\n");
 605 #endif
 606                 return ((uint8_t)0);
 607         }
 608
 609         if (pktattr->pattr_af == AF_INET) {
 610                 struct ip *ip = (struct ip *)pktattr->pattr_hdr;
 611
 612                 if (ip->ip_v != 4)
 613                         return ((uint8_t)0);    /* version mismatch! */
 614                 ds_field = ip->ip_tos;
 615         }
 616 #ifdef INET6
 617         else if (pktattr->pattr_af == AF_INET6) {
 618                 struct ip6_hdr *ip6 = (struct ip6_hdr *)pktattr->pattr_hdr;
 619                 uint32_t flowlabel;
 620
 621                 flowlabel = ntohl(ip6->ip6_flow);
 622                 if ((flowlabel >> 28) != 6)
 623                         return ((uint8_t)0);    /* version mismatch! */
 624                 ds_field = (flowlabel >> 20) & 0xff;
 625         }
 626 #endif
 627         return (ds_field);
 628 }
 629
 630 void
 631 write_dsfield(struct mbuf *m, struct altq_pktattr *pktattr, uint8_t dsfield)
 632 {
 633         struct mbuf *m0;
 634
 635         if (pktattr == NULL ||
 636             (pktattr->pattr_af != AF_INET && pktattr->pattr_af != AF_INET6))
 637                 return;
 638
 639         /* verify that pattr_hdr is within the mbuf data */
 640         for (m0 = m; m0 != NULL; m0 = m0->m_next) {
 641                 if ((pktattr->pattr_hdr >= m0->m_data) &&
 642                     (pktattr->pattr_hdr < m0->m_data + m0->m_len))
 643                         break;
 644         }
 645         if (m0 == NULL) {
 646                 /* ick, pattr_hdr is stale */
 647                 pktattr->pattr_af = AF_UNSPEC;
 648 #ifdef ALTQ_DEBUG
 649                 kprintf("write_dsfield: can't locate header!\n");
 650 #endif
 651                 return;
 652         }
 653
 654         if (pktattr->pattr_af == AF_INET) {
 655                 struct ip *ip = (struct ip *)pktattr->pattr_hdr;
 656                 uint8_t old;
 657                 int32_t sum;
 658
 659                 if (ip->ip_v != 4)
 660                         return;         /* version mismatch! */
 661                 old = ip->ip_tos;
 662                 dsfield |= old & 3;     /* leave CU bits */
 663                 if (old == dsfield)
 664                         return;
 665                 ip->ip_tos = dsfield;
 666                 /*
 667                  * update checksum (from RFC1624)
 668                  *         HC' = ~(~HC + ~m + m')
 669                  */
 670                 sum = ~ntohs(ip->ip_sum) & 0xffff;
 671                 sum += 0xff00 + (~old & 0xff) + dsfield;
 672                 sum = (sum >> 16) + (sum & 0xffff);
 673                 sum += (sum >> 16);  /* add carry */
 674
 675                 ip->ip_sum = htons(~sum & 0xffff);
 676         }
 677 #ifdef INET6
 678         else if (pktattr->pattr_af == AF_INET6) {
 679                 struct ip6_hdr *ip6 = (struct ip6_hdr *)pktattr->pattr_hdr;
 680                 uint32_t flowlabel;
 681
 682                 flowlabel = ntohl(ip6->ip6_flow);
 683                 if ((flowlabel >> 28) != 6)
 684                         return;         /* version mismatch! */
 685                 flowlabel = (flowlabel & 0xf03fffff) | (dsfield << 20);
 686                 ip6->ip6_flow = htonl(flowlabel);
 687         }
 688 #endif
 689 }
 690
 691 /*
 692  * high resolution clock support taking advantage of a machine dependent
 693  * high resolution time counter (e.g., timestamp counter of intel pentium).
 694  * we assume
 695  *  - 64-bit-long monotonically-increasing counter
 696  *  - frequency range is 100M-4GHz (CPU speed)
 697  */
 698 /* if pcc is not available or disabled, emulate 256MHz using microtime() */
 699 #define MACHCLK_SHIFT   8
 700
 701 int machclk_usepcc;
 702 uint32_t machclk_freq = 0;
 703 uint32_t machclk_per_tick = 0;
 704
 705 void
 706 init_machclk(void)
 707 {
 708         callout_init(&tbr_callout);
 709
 710         machclk_usepcc = 1;
 711
 712 #if !defined(__i386__) || defined(ALTQ_NOPCC)
 713         machclk_usepcc = 0;
 714 #elif defined(__DragonFly__) && defined(SMP)
 715         machclk_usepcc = 0;
 716 #elif defined(__i386__)
 717         /* check if TSC is available */
 718         if (machclk_usepcc == 1 && (cpu_feature & CPUID_TSC) == 0)
 719                 machclk_usepcc = 0;
 720 #endif
 721
 722         if (machclk_usepcc == 0) {
 723                 /* emulate 256MHz using microtime() */
 724                 machclk_freq = 1000000 << MACHCLK_SHIFT;
 725                 machclk_per_tick = machclk_freq / hz;
 726 #ifdef ALTQ_DEBUG
 727                 kprintf("altq: emulate %uHz cpu clock\n", machclk_freq);
 728 #endif
 729                 return;
 730         }
 731
 732         /*
 733          * if the clock frequency (of Pentium TSC or Alpha PCC) is
 734          * accessible, just use it.
 735          */
 736 #ifdef __i386__
 737         machclk_freq = tsc_freq;
 738 #else
 739 #error "machclk_freq interface not implemented"
 740 #endif
 741
 742         /*
 743          * if we don't know the clock frequency, measure it.
 744          */
 745         if (machclk_freq == 0) {
 746                 static int      wait;
 747                 struct timeval  tv_start, tv_end;
 748                 uint64_t        start, end, diff;
 749                 int             timo;
 750
 751                 microtime(&tv_start);
 752                 start = read_machclk();
 753                 timo = hz;      /* 1 sec */
 754                 tsleep(&wait, PCATCH, "init_machclk", timo);
 755                 microtime(&tv_end);
 756                 end = read_machclk();
 757                 diff = (uint64_t)(tv_end.tv_sec - tv_start.tv_sec) * 1000000
 758                     + tv_end.tv_usec - tv_start.tv_usec;
 759                 if (diff != 0)
 760                         machclk_freq = (u_int)((end - start) * 1000000 / diff);
 761         }
 762
 763         machclk_per_tick = machclk_freq / hz;
 764
 765 #ifdef ALTQ_DEBUG
 766         kprintf("altq: CPU clock: %uHz\n", machclk_freq);
 767 #endif
 768 }
 769
 770 uint64_t
 771 read_machclk(void)
 772 {
 773         uint64_t val;
 774
 775         if (machclk_usepcc) {
 776 #if defined(__i386__)
 777                 val = rdtsc();
 778 #else
 779                 panic("read_machclk");
 780 #endif
 781         } else {
 782                 struct timeval tv;
 783
 784                 microtime(&tv);
 785                 val = (((uint64_t)(tv.tv_sec - boottime.tv_sec) * 1000000
 786                     + tv.tv_usec) << MACHCLK_SHIFT);
 787         }
 788         return (val);
 789 }