net/sched/sch_hfsc.c

   1 /*
   2  * Copyright (c) 2003 Patrick McHardy, <kaber@trash.net>
   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 2
   7  * of the License, or (at your option) any later version.
   8  *
   9  * 2003-10-17 - Ported from altq
  10  */
  11 /*
  12  * Copyright (c) 1997-1999 Carnegie Mellon University. All Rights Reserved.
  13  *
  14  * Permission to use, copy, modify, and distribute this software and
  15  * its documentation is hereby granted (including for commercial or
  16  * for-profit use), provided that both the copyright notice and this
  17  * permission notice appear in all copies of the software, derivative
  18  * works, or modified versions, and any portions thereof.
  19  *
  20  * THIS SOFTWARE IS EXPERIMENTAL AND IS KNOWN TO HAVE BUGS, SOME OF
  21  * WHICH MAY HAVE SERIOUS CONSEQUENCES.  CARNEGIE MELLON PROVIDES THIS
  22  * SOFTWARE IN ITS ``AS IS'' CONDITION, AND ANY EXPRESS OR IMPLIED
  23  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  25  * DISCLAIMED.  IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY BE LIABLE
  26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  27  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
  28  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  29  * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  30  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  31  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
  32  * USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
  33  * DAMAGE.
  34  *
  35  * Carnegie Mellon encourages (but does not require) users of this
  36  * software to return any improvements or extensions that they make,
  37  * and to grant Carnegie Mellon the rights to redistribute these
  38  * changes without encumbrance.
  39  */
  40 /*
  41  * H-FSC is described in Proceedings of SIGCOMM'97,
  42  * "A Hierarchical Fair Service Curve Algorithm for Link-Sharing,
  43  * Real-Time and Priority Service"
  44  * by Ion Stoica, Hui Zhang, and T. S. Eugene Ng.
  45  *
  46  * Oleg Cherevko <olwi@aq.ml.com.ua> added the upperlimit for link-sharing.
  47  * when a class has an upperlimit, the fit-time is computed from the
  48  * upperlimit service curve.  the link-sharing scheduler does not schedule
  49  * a class whose fit-time exceeds the current time.
  50  */
  51
  52 #include <linux/kernel.h>
  53 #include <linux/config.h>
  54 #include <linux/module.h>
  55 #include <linux/types.h>
  56 #include <linux/errno.h>
  57 #include <linux/jiffies.h>
  58 #include <linux/compiler.h>
  59 #include <linux/spinlock.h>
  60 #include <linux/skbuff.h>
  61 #include <linux/string.h>
  62 #include <linux/slab.h>
  63 #include <linux/timer.h>
  64 #include <linux/list.h>
  65 #include <linux/rbtree.h>
  66 #include <linux/init.h>
  67 #include <linux/netdevice.h>
  68 #include <linux/rtnetlink.h>
  69 #include <linux/pkt_sched.h>
  70 #include <net/pkt_sched.h>
  71 #include <net/pkt_cls.h>
  72 #include <asm/system.h>
  73 #include <asm/div64.h>
  74
  75 #define HFSC_DEBUG 1
  76
  77 /*
  78  * kernel internal service curve representation:
  79  *   coordinates are given by 64 bit unsigned integers.
  80  *   x-axis: unit is clock count.
  81  *   y-axis: unit is byte.
  82  *
  83  *   The service curve parameters are converted to the internal
  84  *   representation. The slope values are scaled to avoid overflow.
  85  *   the inverse slope values as well as the y-projection of the 1st
  86  *   segment are kept in order to to avoid 64-bit divide operations
  87  *   that are expensive on 32-bit architectures.
  88  */
  89
  90 struct internal_sc
  91 {
  92         u64     sm1;    /* scaled slope of the 1st segment */
  93         u64     ism1;   /* scaled inverse-slope of the 1st segment */
  94         u64     dx;     /* the x-projection of the 1st segment */
  95         u64     dy;     /* the y-projection of the 1st segment */
  96         u64     sm2;    /* scaled slope of the 2nd segment */
  97         u64     ism2;   /* scaled inverse-slope of the 2nd segment */
  98 };
  99
 100 /* runtime service curve */
 101 struct runtime_sc
 102 {
 103         u64     x;      /* current starting position on x-axis */
 104         u64     y;      /* current starting position on y-axis */
 105         u64     sm1;    /* scaled slope of the 1st segment */
 106         u64     ism1;   /* scaled inverse-slope of the 1st segment */
 107         u64     dx;     /* the x-projection of the 1st segment */
 108         u64     dy;     /* the y-projection of the 1st segment */
 109         u64     sm2;    /* scaled slope of the 2nd segment */
 110         u64     ism2;   /* scaled inverse-slope of the 2nd segment */
 111 };
 112
 113 enum hfsc_class_flags
 114 {
 115         HFSC_RSC = 0x1,
 116         HFSC_FSC = 0x2,
 117         HFSC_USC = 0x4
 118 };
 119
 120 struct hfsc_class
 121 {
 122         u32             classid;        /* class id */
 123         unsigned int    refcnt;         /* usage count */
 124
 125         struct gnet_stats_basic bstats;
 126         struct gnet_stats_queue qstats;
 127         struct gnet_stats_rate_est rate_est;
 128         spinlock_t      *stats_lock;
 129         unsigned int    level;          /* class level in hierarchy */
 130         struct tcf_proto *filter_list;  /* filter list */
 131         unsigned int    filter_cnt;     /* filter count */
 132
 133         struct hfsc_sched *sched;       /* scheduler data */
 134         struct hfsc_class *cl_parent;   /* parent class */
 135         struct list_head siblings;      /* sibling classes */
 136         struct list_head children;      /* child classes */
 137         struct Qdisc    *qdisc;         /* leaf qdisc */
 138
 139         struct rb_node el_node;         /* qdisc's eligible tree member */
 140         struct rb_root vt_tree;         /* active children sorted by cl_vt */
 141         struct rb_node vt_node;         /* parent's vt_tree member */
 142         struct rb_root cf_tree;         /* active children sorted by cl_f */
 143         struct rb_node cf_node;         /* parent's cf_heap member */
 144         struct list_head hlist;         /* hash list member */
 145         struct list_head dlist;         /* drop list member */
 146
 147         u64     cl_total;               /* total work in bytes */
 148         u64     cl_cumul;               /* cumulative work in bytes done by
 149                                            real-time criteria */
 150
 151         u64     cl_d;                   /* deadline*/
 152         u64     cl_e;                   /* eligible time */
 153         u64     cl_vt;                  /* virtual time */
 154         u64     cl_f;                   /* time when this class will fit for
 155                                            link-sharing, max(myf, cfmin) */
 156         u64     cl_myf;                 /* my fit-time (calculated from this
 157                                            class's own upperlimit curve) */
 158         u64     cl_myfadj;              /* my fit-time adjustment (to cancel
 159                                            history dependence) */
 160         u64     cl_cfmin;               /* earliest children's fit-time (used
 161                                            with cl_myf to obtain cl_f) */
 162         u64     cl_cvtmin;              /* minimal virtual time among the
 163                                            children fit for link-sharing
 164                                            (monotonic within a period) */
 165         u64     cl_vtadj;               /* intra-period cumulative vt
 166                                            adjustment */
 167         u64     cl_vtoff;               /* inter-period cumulative vt offset */
 168         u64     cl_cvtmax;              /* max child's vt in the last period */
 169         u64     cl_cvtoff;              /* cumulative cvtmax of all periods */
 170         u64     cl_pcvtoff;             /* parent's cvtoff at initalization
 171                                            time */
 172
 173         struct internal_sc cl_rsc;      /* internal real-time service curve */
 174         struct internal_sc cl_fsc;      /* internal fair service curve */
 175         struct internal_sc cl_usc;      /* internal upperlimit service curve */
 176         struct runtime_sc cl_deadline;  /* deadline curve */
 177         struct runtime_sc cl_eligible;  /* eligible curve */
 178         struct runtime_sc cl_virtual;   /* virtual curve */
 179         struct runtime_sc cl_ulimit;    /* upperlimit curve */
 180
 181         unsigned long   cl_flags;       /* which curves are valid */
 182         unsigned long   cl_vtperiod;    /* vt period sequence number */
 183         unsigned long   cl_parentperiod;/* parent's vt period sequence number*/
 184         unsigned long   cl_nactive;     /* number of active children */
 185 };
 186
 187 #define HFSC_HSIZE      16
 188
 189 struct hfsc_sched
 190 {
 191         u16     defcls;                         /* default class id */
 192         struct hfsc_class root;                 /* root class */
 193         struct list_head clhash[HFSC_HSIZE];    /* class hash */
 194         struct rb_root eligible;                /* eligible tree */
 195         struct list_head droplist;              /* active leaf class list (for
 196                                                    dropping) */
 197         struct sk_buff_head requeue;            /* requeued packet */
 198         struct timer_list wd_timer;             /* watchdog timer */
 199 };
 200
 201 /*
 202  * macros
 203  */
 204 #ifdef CONFIG_NET_SCH_CLK_GETTIMEOFDAY
 205 #include <linux/time.h>
 206 #undef PSCHED_GET_TIME
 207 #define PSCHED_GET_TIME(stamp)                                          \
 208 do {                                                                    \
 209         struct timeval tv;                                              \
 210         do_gettimeofday(&tv);                                           \
 211         (stamp) = 1ULL * USEC_PER_SEC * tv.tv_sec + tv.tv_usec;         \
 212 } while (0)
 213 #endif
 214
 215 #if HFSC_DEBUG
 216 #define ASSERT(cond)                                                    \
 217 do {                                                                    \
 218         if (unlikely(!(cond)))                                          \
 219                 printk("assertion %s failed at %s:%i (%s)\n",           \
 220                        #cond, __FILE__, __LINE__, __FUNCTION__);        \
 221 } while (0)
 222 #else
 223 #define ASSERT(cond)
 224 #endif /* HFSC_DEBUG */
 225
 226 #define HT_INFINITY     0xffffffffffffffffULL   /* infinite time value */
 227
 228
 229 /*
 230  * eligible tree holds backlogged classes being sorted by their eligible times.
 231  * there is one eligible tree per hfsc instance.
 232  */
 233
 234 static void
 235 eltree_insert(struct hfsc_class *cl)
 236 {
 237         struct rb_node **p = &cl->sched->eligible.rb_node;
 238         struct rb_node *parent = NULL;
 239         struct hfsc_class *cl1;
 240
 241         while (*p != NULL) {
 242                 parent = *p;
 243                 cl1 = rb_entry(parent, struct hfsc_class, el_node);
 244                 if (cl->cl_e >= cl1->cl_e)
 245                         p = &parent->rb_right;
 246                 else
 247                         p = &parent->rb_left;
 248         }
 249         rb_link_node(&cl->el_node, parent, p);
 250         rb_insert_color(&cl->el_node, &cl->sched->eligible);
 251 }
 252
 253 static inline void
 254 eltree_remove(struct hfsc_class *cl)
 255 {
 256         rb_erase(&cl->el_node, &cl->sched->eligible);
 257 }
 258
 259 static inline void
 260 eltree_update(struct hfsc_class *cl)
 261 {
 262         eltree_remove(cl);
 263         eltree_insert(cl);
 264 }
 265
 266 /* find the class with the minimum deadline among the eligible classes */
 267 static inline struct hfsc_class *
 268 eltree_get_mindl(struct hfsc_sched *q, u64 cur_time)
 269 {
 270         struct hfsc_class *p, *cl = NULL;
 271         struct rb_node *n;
 272
 273         for (n = rb_first(&q->eligible); n != NULL; n = rb_next(n)) {
 274                 p = rb_entry(n, struct hfsc_class, el_node);
 275                 if (p->cl_e > cur_time)
 276                         break;
 277                 if (cl == NULL || p->cl_d < cl->cl_d)
 278                         cl = p;
 279         }
 280         return cl;
 281 }
 282
 283 /* find the class with minimum eligible time among the eligible classes */
 284 static inline struct hfsc_class *
 285 eltree_get_minel(struct hfsc_sched *q)
 286 {
 287         struct rb_node *n;
 288
 289         n = rb_first(&q->eligible);
 290         if (n == NULL)
 291                 return NULL;
 292         return rb_entry(n, struct hfsc_class, el_node);
 293 }
 294
 295 /*
 296  * vttree holds holds backlogged child classes being sorted by their virtual
 297  * time. each intermediate class has one vttree.
 298  */
 299 static void
 300 vttree_insert(struct hfsc_class *cl)
 301 {
 302         struct rb_node **p = &cl->cl_parent->vt_tree.rb_node;
 303         struct rb_node *parent = NULL;
 304         struct hfsc_class *cl1;
 305
 306         while (*p != NULL) {
 307                 parent = *p;
 308                 cl1 = rb_entry(parent, struct hfsc_class, vt_node);
 309                 if (cl->cl_vt >= cl1->cl_vt)
 310                         p = &parent->rb_right;
 311                 else
 312                         p = &parent->rb_left;
 313         }
 314         rb_link_node(&cl->vt_node, parent, p);
 315         rb_insert_color(&cl->vt_node, &cl->cl_parent->vt_tree);
 316 }
 317
 318 static inline void
 319 vttree_remove(struct hfsc_class *cl)
 320 {
 321         rb_erase(&cl->vt_node, &cl->cl_parent->vt_tree);
 322 }
 323
 324 static inline void
 325 vttree_update(struct hfsc_class *cl)
 326 {
 327         vttree_remove(cl);
 328         vttree_insert(cl);
 329 }
 330
 331 static inline struct hfsc_class *
 332 vttree_firstfit(struct hfsc_class *cl, u64 cur_time)
 333 {
 334         struct hfsc_class *p;
 335         struct rb_node *n;
 336
 337         for (n = rb_first(&cl->vt_tree); n != NULL; n = rb_next(n)) {
 338                 p = rb_entry(n, struct hfsc_class, vt_node);
 339                 if (p->cl_f <= cur_time)
 340                         return p;
 341         }
 342         return NULL;
 343 }
 344
 345 /*
 346  * get the leaf class with the minimum vt in the hierarchy
 347  */
 348 static struct hfsc_class *
 349 vttree_get_minvt(struct hfsc_class *cl, u64 cur_time)
 350 {
 351         /* if root-class's cfmin is bigger than cur_time nothing to do */
 352         if (cl->cl_cfmin > cur_time)
 353                 return NULL;
 354
 355         while (cl->level > 0) {
 356                 cl = vttree_firstfit(cl, cur_time);
 357                 if (cl == NULL)
 358                         return NULL;
 359                 /*
 360                  * update parent's cl_cvtmin.
 361                  */
 362                 if (cl->cl_parent->cl_cvtmin < cl->cl_vt)
 363                         cl->cl_parent->cl_cvtmin = cl->cl_vt;
 364         }
 365         return cl;
 366 }
 367
 368 static void
 369 cftree_insert(struct hfsc_class *cl)
 370 {
 371         struct rb_node **p = &cl->cl_parent->cf_tree.rb_node;
 372         struct rb_node *parent = NULL;
 373         struct hfsc_class *cl1;
 374
 375         while (*p != NULL) {
 376                 parent = *p;
 377                 cl1 = rb_entry(parent, struct hfsc_class, cf_node);
 378                 if (cl->cl_f >= cl1->cl_f)
 379                         p = &parent->rb_right;
 380                 else
 381                         p = &parent->rb_left;
 382         }
 383         rb_link_node(&cl->cf_node, parent, p);
 384         rb_insert_color(&cl->cf_node, &cl->cl_parent->cf_tree);
 385 }
 386
 387 static inline void
 388 cftree_remove(struct hfsc_class *cl)
 389 {
 390         rb_erase(&cl->cf_node, &cl->cl_parent->cf_tree);
 391 }
 392
 393 static inline void
 394 cftree_update(struct hfsc_class *cl)
 395 {
 396         cftree_remove(cl);
 397         cftree_insert(cl);
 398 }
 399
 400 /*
 401  * service curve support functions
 402  *
 403  *  external service curve parameters
 404  *      m: bps
 405  *      d: us
 406  *  internal service curve parameters
 407  *      sm: (bytes/psched_us) << SM_SHIFT
 408  *      ism: (psched_us/byte) << ISM_SHIFT
 409  *      dx: psched_us
 410  *
 411  * Clock source resolution (CONFIG_NET_SCH_CLK_*)
 412  *  JIFFIES: for 48<=HZ<=1534 resolution is between 0.63us and 1.27us.
 413  *  CPU: resolution is between 0.5us and 1us.
 414  *  GETTIMEOFDAY: resolution is exactly 1us.
 415  *
 416  * sm and ism are scaled in order to keep effective digits.
 417  * SM_SHIFT and ISM_SHIFT are selected to keep at least 4 effective
 418  * digits in decimal using the following table.
 419  *
 420  * Note: We can afford the additional accuracy (altq hfsc keeps at most
 421  * 3 effective digits) thanks to the fact that linux clock is bounded
 422  * much more tightly.
 423  *
 424  *  bits/sec      100Kbps     1Mbps     10Mbps     100Mbps    1Gbps
 425  *  ------------+-------------------------------------------------------
 426  *  bytes/0.5us   6.25e-3    62.5e-3    625e-3     6250e-e    62500e-3
 427  *  bytes/us      12.5e-3    125e-3     1250e-3    12500e-3   125000e-3
 428  *  bytes/1.27us  15.875e-3  158.75e-3  1587.5e-3  15875e-3   158750e-3
 429  *
 430  *  0.5us/byte    160        16         1.6        0.16       0.016
 431  *  us/byte       80         8          0.8        0.08       0.008
 432  *  1.27us/byte   63         6.3        0.63       0.063      0.0063
 433  */
 434 #define SM_SHIFT        20
 435 #define ISM_SHIFT       18
 436
 437 #define SM_MASK         ((1ULL << SM_SHIFT) - 1)
 438 #define ISM_MASK        ((1ULL << ISM_SHIFT) - 1)
 439
 440 static inline u64
 441 seg_x2y(u64 x, u64 sm)
 442 {
 443         u64 y;
 444
 445         /*
 446          * compute
 447          *      y = x * sm >> SM_SHIFT
 448          * but divide it for the upper and lower bits to avoid overflow
 449          */
 450         y = (x >> SM_SHIFT) * sm + (((x & SM_MASK) * sm) >> SM_SHIFT);
 451         return y;
 452 }
 453
 454 static inline u64
 455 seg_y2x(u64 y, u64 ism)
 456 {
 457         u64 x;
 458
 459         if (y == 0)
 460                 x = 0;
 461         else if (ism == HT_INFINITY)
 462                 x = HT_INFINITY;
 463         else {
 464                 x = (y >> ISM_SHIFT) * ism
 465                     + (((y & ISM_MASK) * ism) >> ISM_SHIFT);
 466         }
 467         return x;
 468 }
 469
 470 /* Convert m (bps) into sm (bytes/psched us) */
 471 static u64
 472 m2sm(u32 m)
 473 {
 474         u64 sm;
 475
 476         sm = ((u64)m << SM_SHIFT);
 477         sm += PSCHED_JIFFIE2US(HZ) - 1;
 478         do_div(sm, PSCHED_JIFFIE2US(HZ));
 479         return sm;
 480 }
 481
 482 /* convert m (bps) into ism (psched us/byte) */
 483 static u64
 484 m2ism(u32 m)
 485 {
 486         u64 ism;
 487
 488         if (m == 0)
 489                 ism = HT_INFINITY;
 490         else {
 491                 ism = ((u64)PSCHED_JIFFIE2US(HZ) << ISM_SHIFT);
 492                 ism += m - 1;
 493                 do_div(ism, m);
 494         }
 495         return ism;
 496 }
 497
 498 /* convert d (us) into dx (psched us) */
 499 static u64
 500 d2dx(u32 d)
 501 {
 502         u64 dx;
 503
 504         dx = ((u64)d * PSCHED_JIFFIE2US(HZ));
 505         dx += USEC_PER_SEC - 1;
 506         do_div(dx, USEC_PER_SEC);
 507         return dx;
 508 }
 509
 510 /* convert sm (bytes/psched us) into m (bps) */
 511 static u32
 512 sm2m(u64 sm)
 513 {
 514         u64 m;
 515
 516         m = (sm * PSCHED_JIFFIE2US(HZ)) >> SM_SHIFT;
 517         return (u32)m;
 518 }
 519
 520 /* convert dx (psched us) into d (us) */
 521 static u32
 522 dx2d(u64 dx)
 523 {
 524         u64 d;
 525
 526         d = dx * USEC_PER_SEC;
 527         do_div(d, PSCHED_JIFFIE2US(HZ));
 528         return (u32)d;
 529 }
 530
 531 static void
 532 sc2isc(struct tc_service_curve *sc, struct internal_sc *isc)
 533 {
 534         isc->sm1  = m2sm(sc->m1);
 535         isc->ism1 = m2ism(sc->m1);
 536         isc->dx   = d2dx(sc->d);
 537         isc->dy   = seg_x2y(isc->dx, isc->sm1);
 538         isc->sm2  = m2sm(sc->m2);
 539         isc->ism2 = m2ism(sc->m2);
 540 }
 541
 542 /*
 543  * initialize the runtime service curve with the given internal
 544  * service curve starting at (x, y).
 545  */
 546 static void
 547 rtsc_init(struct runtime_sc *rtsc, struct internal_sc *isc, u64 x, u64 y)
 548 {
 549         rtsc->x    = x;
 550         rtsc->y    = y;
 551         rtsc->sm1  = isc->sm1;
 552         rtsc->ism1 = isc->ism1;
 553         rtsc->dx   = isc->dx;
 554         rtsc->dy   = isc->dy;
 555         rtsc->sm2  = isc->sm2;
 556         rtsc->ism2 = isc->ism2;
 557 }
 558
 559 /*
 560  * calculate the y-projection of the runtime service curve by the
 561  * given x-projection value
 562  */
 563 static u64
 564 rtsc_y2x(struct runtime_sc *rtsc, u64 y)
 565 {
 566         u64 x;
 567
 568         if (y < rtsc->y)
 569                 x = rtsc->x;
 570         else if (y <= rtsc->y + rtsc->dy) {
 571                 /* x belongs to the 1st segment */
 572                 if (rtsc->dy == 0)
 573                         x = rtsc->x + rtsc->dx;
 574                 else
 575                         x = rtsc->x + seg_y2x(y - rtsc->y, rtsc->ism1);
 576         } else {
 577                 /* x belongs to the 2nd segment */
 578                 x = rtsc->x + rtsc->dx
 579                     + seg_y2x(y - rtsc->y - rtsc->dy, rtsc->ism2);
 580         }
 581         return x;
 582 }
 583
 584 static u64
 585 rtsc_x2y(struct runtime_sc *rtsc, u64 x)
 586 {
 587         u64 y;
 588
 589         if (x <= rtsc->x)
 590                 y = rtsc->y;
 591         else if (x <= rtsc->x + rtsc->dx)
 592                 /* y belongs to the 1st segment */
 593                 y = rtsc->y + seg_x2y(x - rtsc->x, rtsc->sm1);
 594         else
 595                 /* y belongs to the 2nd segment */
 596                 y = rtsc->y + rtsc->dy
 597                     + seg_x2y(x - rtsc->x - rtsc->dx, rtsc->sm2);
 598         return y;
 599 }
 600
 601 /*
 602  * update the runtime service curve by taking the minimum of the current
 603  * runtime service curve and the service curve starting at (x, y).
 604  */
 605 static void
 606 rtsc_min(struct runtime_sc *rtsc, struct internal_sc *isc, u64 x, u64 y)
 607 {
 608         u64 y1, y2, dx, dy;
 609         u32 dsm;
 610
 611         if (isc->sm1 <= isc->sm2) {
 612                 /* service curve is convex */
 613                 y1 = rtsc_x2y(rtsc, x);
 614                 if (y1 < y)
 615                         /* the current rtsc is smaller */
 616                         return;
 617                 rtsc->x = x;
 618                 rtsc->y = y;
 619                 return;
 620         }
 621
 622         /*
 623          * service curve is concave
 624          * compute the two y values of the current rtsc
 625          *      y1: at x
 626          *      y2: at (x + dx)
 627          */
 628         y1 = rtsc_x2y(rtsc, x);
 629         if (y1 <= y) {
 630                 /* rtsc is below isc, no change to rtsc */
 631                 return;
 632         }
 633
 634         y2 = rtsc_x2y(rtsc, x + isc->dx);
 635         if (y2 >= y + isc->dy) {
 636                 /* rtsc is above isc, replace rtsc by isc */
 637                 rtsc->x = x;
 638                 rtsc->y = y;
 639                 rtsc->dx = isc->dx;
 640                 rtsc->dy = isc->dy;
 641                 return;
 642         }
 643
 644         /*
 645          * the two curves intersect
 646          * compute the offsets (dx, dy) using the reverse
 647          * function of seg_x2y()
 648          *      seg_x2y(dx, sm1) == seg_x2y(dx, sm2) + (y1 - y)
 649          */
 650         dx = (y1 - y) << SM_SHIFT;
 651         dsm = isc->sm1 - isc->sm2;
 652         do_div(dx, dsm);
 653         /*
 654          * check if (x, y1) belongs to the 1st segment of rtsc.
 655          * if so, add the offset.
 656          */
 657         if (rtsc->x + rtsc->dx > x)
 658                 dx += rtsc->x + rtsc->dx - x;
 659         dy = seg_x2y(dx, isc->sm1);
 660
 661         rtsc->x = x;
 662         rtsc->y = y;
 663         rtsc->dx = dx;
 664         rtsc->dy = dy;
 665         return;
 666 }
 667
 668 static void
 669 init_ed(struct hfsc_class *cl, unsigned int next_len)
 670 {
 671         u64 cur_time;
 672
 673         PSCHED_GET_TIME(cur_time);
 674
 675         /* update the deadline curve */
 676         rtsc_min(&cl->cl_deadline, &cl->cl_rsc, cur_time, cl->cl_cumul);
 677
 678         /*
 679          * update the eligible curve.
 680          * for concave, it is equal to the deadline curve.
 681          * for convex, it is a linear curve with slope m2.
 682          */
 683         cl->cl_eligible = cl->cl_deadline;
 684         if (cl->cl_rsc.sm1 <= cl->cl_rsc.sm2) {
 685                 cl->cl_eligible.dx = 0;
 686                 cl->cl_eligible.dy = 0;
 687         }
 688
 689         /* compute e and d */
 690         cl->cl_e = rtsc_y2x(&cl->cl_eligible, cl->cl_cumul);
 691         cl->cl_d = rtsc_y2x(&cl->cl_deadline, cl->cl_cumul + next_len);
 692
 693         eltree_insert(cl);
 694 }
 695
 696 static void
 697 update_ed(struct hfsc_class *cl, unsigned int next_len)
 698 {
 699         cl->cl_e = rtsc_y2x(&cl->cl_eligible, cl->cl_cumul);
 700         cl->cl_d = rtsc_y2x(&cl->cl_deadline, cl->cl_cumul + next_len);
 701
 702         eltree_update(cl);
 703 }
 704
 705 static inline void
 706 update_d(struct hfsc_class *cl, unsigned int next_len)
 707 {
 708         cl->cl_d = rtsc_y2x(&cl->cl_deadline, cl->cl_cumul + next_len);
 709 }
 710
 711 static inline void
 712 update_cfmin(struct hfsc_class *cl)
 713 {
 714         struct rb_node *n = rb_first(&cl->cf_tree);
 715         struct hfsc_class *p;
 716
 717         if (n == NULL) {
 718                 cl->cl_cfmin = 0;
 719                 return;
 720         }
 721         p = rb_entry(n, struct hfsc_class, cf_node);
 722         cl->cl_cfmin = p->cl_f;
 723 }
 724
 725 static void
 726 init_vf(struct hfsc_class *cl, unsigned int len)
 727 {
 728         struct hfsc_class *max_cl;
 729         struct rb_node *n;
 730         u64 vt, f, cur_time;
 731         int go_active;
 732
 733         cur_time = 0;
 734         go_active = 1;
 735         for (; cl->cl_parent != NULL; cl = cl->cl_parent) {
 736                 if (go_active && cl->cl_nactive++ == 0)
 737                         go_active = 1;
 738                 else
 739                         go_active = 0;
 740
 741                 if (go_active) {
 742                         n = rb_last(&cl->cl_parent->vt_tree);
 743                         if (n != NULL) {
 744                                 max_cl = rb_entry(n, struct hfsc_class,vt_node);
 745                                 /*
 746                                  * set vt to the average of the min and max
 747                                  * classes.  if the parent's period didn't
 748                                  * change, don't decrease vt of the class.
 749                                  */
 750                                 vt = max_cl->cl_vt;
 751                                 if (cl->cl_parent->cl_cvtmin != 0)
 752                                         vt = (cl->cl_parent->cl_cvtmin + vt)/2;
 753
 754                                 if (cl->cl_parent->cl_vtperiod !=
 755                                     cl->cl_parentperiod || vt > cl->cl_vt)
 756                                         cl->cl_vt = vt;
 757                         } else {
 758                                 /*
 759                                  * first child for a new parent backlog period.
 760                                  * add parent's cvtmax to cvtoff to make a new
 761                                  * vt (vtoff + vt) larger than the vt in the
 762                                  * last period for all children.
 763                                  */
 764                                 vt = cl->cl_parent->cl_cvtmax;
 765                                 cl->cl_parent->cl_cvtoff += vt;
 766                                 cl->cl_parent->cl_cvtmax = 0;
 767                                 cl->cl_parent->cl_cvtmin = 0;
 768                                 cl->cl_vt = 0;
 769                         }
 770
 771                         cl->cl_vtoff = cl->cl_parent->cl_cvtoff -
 772                                                         cl->cl_pcvtoff;
 773
 774                         /* update the virtual curve */
 775                         vt = cl->cl_vt + cl->cl_vtoff;
 776                         rtsc_min(&cl->cl_virtual, &cl->cl_fsc, vt,
 777                                                       cl->cl_total);
 778                         if (cl->cl_virtual.x == vt) {
 779                                 cl->cl_virtual.x -= cl->cl_vtoff;
 780                                 cl->cl_vtoff = 0;
 781                         }
 782                         cl->cl_vtadj = 0;
 783
 784                         cl->cl_vtperiod++;  /* increment vt period */
 785                         cl->cl_parentperiod = cl->cl_parent->cl_vtperiod;
 786                         if (cl->cl_parent->cl_nactive == 0)
 787                                 cl->cl_parentperiod++;
 788                         cl->cl_f = 0;
 789
 790                         vttree_insert(cl);
 791                         cftree_insert(cl);
 792
 793                         if (cl->cl_flags & HFSC_USC) {
 794                                 /* class has upper limit curve */
 795                                 if (cur_time == 0)
 796                                         PSCHED_GET_TIME(cur_time);
 797
 798                                 /* update the ulimit curve */
 799                                 rtsc_min(&cl->cl_ulimit, &cl->cl_usc, cur_time,
 800                                          cl->cl_total);
 801                                 /* compute myf */
 802                                 cl->cl_myf = rtsc_y2x(&cl->cl_ulimit,
 803                                                       cl->cl_total);
 804                                 cl->cl_myfadj = 0;
 805                         }
 806                 }
 807
 808                 f = max(cl->cl_myf, cl->cl_cfmin);
 809                 if (f != cl->cl_f) {
 810                         cl->cl_f = f;
 811                         cftree_update(cl);
 812                         update_cfmin(cl->cl_parent);
 813                 }
 814         }
 815 }
 816
 817 static void
 818 update_vf(struct hfsc_class *cl, unsigned int len, u64 cur_time)
 819 {
 820         u64 f; /* , myf_bound, delta; */
 821         int go_passive = 0;
 822
 823         if (cl->qdisc->q.qlen == 0 && cl->cl_flags & HFSC_FSC)
 824                 go_passive = 1;
 825
 826         for (; cl->cl_parent != NULL; cl = cl->cl_parent) {
 827                 cl->cl_total += len;
 828
 829                 if (!(cl->cl_flags & HFSC_FSC) || cl->cl_nactive == 0)
 830                         continue;
 831
 832                 if (go_passive && --cl->cl_nactive == 0)
 833                         go_passive = 1;
 834                 else
 835                         go_passive = 0;
 836
 837                 if (go_passive) {
 838                         /* no more active child, going passive */
 839
 840                         /* update cvtmax of the parent class */
 841                         if (cl->cl_vt > cl->cl_parent->cl_cvtmax)
 842                                 cl->cl_parent->cl_cvtmax = cl->cl_vt;
 843
 844                         /* remove this class from the vt tree */
 845                         vttree_remove(cl);
 846
 847                         cftree_remove(cl);
 848                         update_cfmin(cl->cl_parent);
 849
 850                         continue;
 851                 }
 852
 853                 /*
 854                  * update vt and f
 855                  */
 856                 cl->cl_vt = rtsc_y2x(&cl->cl_virtual, cl->cl_total)
 857                             - cl->cl_vtoff + cl->cl_vtadj;
 858
 859                 /*
 860                  * if vt of the class is smaller than cvtmin,
 861                  * the class was skipped in the past due to non-fit.
 862                  * if so, we need to adjust vtadj.
 863                  */
 864                 if (cl->cl_vt < cl->cl_parent->cl_cvtmin) {
 865                         cl->cl_vtadj += cl->cl_parent->cl_cvtmin - cl->cl_vt;
 866                         cl->cl_vt = cl->cl_parent->cl_cvtmin;
 867                 }
 868
 869                 /* update the vt tree */
 870                 vttree_update(cl);
 871
 872                 if (cl->cl_flags & HFSC_USC) {
 873                         cl->cl_myf = cl->cl_myfadj + rtsc_y2x(&cl->cl_ulimit,
 874                                                               cl->cl_total);
 875 #if 0
 876                         /*
 877                          * This code causes classes to stay way under their
 878                          * limit when multiple classes are used at gigabit
 879                          * speed. needs investigation. -kaber
 880                          */
 881                         /*
 882                          * if myf lags behind by more than one clock tick
 883                          * from the current time, adjust myfadj to prevent
 884                          * a rate-limited class from going greedy.
 885                          * in a steady state under rate-limiting, myf
 886                          * fluctuates within one clock tick.
 887                          */
 888                         myf_bound = cur_time - PSCHED_JIFFIE2US(1);
 889                         if (cl->cl_myf < myf_bound) {
 890                                 delta = cur_time - cl->cl_myf;
 891                                 cl->cl_myfadj += delta;
 892                                 cl->cl_myf += delta;
 893                         }
 894 #endif
 895                 }
 896
 897                 f = max(cl->cl_myf, cl->cl_cfmin);
 898                 if (f != cl->cl_f) {
 899                         cl->cl_f = f;
 900                         cftree_update(cl);
 901                         update_cfmin(cl->cl_parent);
 902                 }
 903         }
 904 }
 905
 906 static void
 907 set_active(struct hfsc_class *cl, unsigned int len)
 908 {
 909         if (cl->cl_flags & HFSC_RSC)
 910                 init_ed(cl, len);
 911         if (cl->cl_flags & HFSC_FSC)
 912                 init_vf(cl, len);
 913
 914         list_add_tail(&cl->dlist, &cl->sched->droplist);
 915 }
 916
 917 static void
 918 set_passive(struct hfsc_class *cl)
 919 {
 920         if (cl->cl_flags & HFSC_RSC)
 921                 eltree_remove(cl);
 922
 923         list_del(&cl->dlist);
 924
 925         /*
 926          * vttree is now handled in update_vf() so that update_vf(cl, 0, 0)
 927          * needs to be called explicitly to remove a class from vttree.
 928          */
 929 }
 930
 931 /*
 932  * hack to get length of first packet in queue.
 933  */
 934 static unsigned int
 935 qdisc_peek_len(struct Qdisc *sch)
 936 {
 937         struct sk_buff *skb;
 938         unsigned int len;
 939
 940         skb = sch->dequeue(sch);
 941         if (skb == NULL) {
 942                 if (net_ratelimit())
 943                         printk("qdisc_peek_len: non work-conserving qdisc ?\n");
 944                 return 0;
 945         }
 946         len = skb->len;
 947         if (unlikely(sch->ops->requeue(skb, sch) != NET_XMIT_SUCCESS)) {
 948                 if (net_ratelimit())
 949                         printk("qdisc_peek_len: failed to requeue\n");
 950                 return 0;
 951         }
 952         return len;
 953 }
 954
 955 static void
 956 hfsc_purge_queue(struct Qdisc *sch, struct hfsc_class *cl)
 957 {
 958         unsigned int len = cl->qdisc->q.qlen;
 959
 960         qdisc_reset(cl->qdisc);
 961         if (len > 0) {
 962                 update_vf(cl, 0, 0);
 963                 set_passive(cl);
 964                 sch->q.qlen -= len;
 965         }
 966 }
 967
 968 static void
 969 hfsc_adjust_levels(struct hfsc_class *cl)
 970 {
 971         struct hfsc_class *p;
 972         unsigned int level;
 973
 974         do {
 975                 level = 0;
 976                 list_for_each_entry(p, &cl->children, siblings) {
 977                         if (p->level >= level)
 978                                 level = p->level + 1;
 979                 }
 980                 cl->level = level;
 981         } while ((cl = cl->cl_parent) != NULL);
 982 }
 983
 984 static inline unsigned int
 985 hfsc_hash(u32 h)
 986 {
 987         h ^= h >> 8;
 988         h ^= h >> 4;
 989
 990         return h & (HFSC_HSIZE - 1);
 991 }
 992
 993 static inline struct hfsc_class *
 994 hfsc_find_class(u32 classid, struct Qdisc *sch)
 995 {
 996         struct hfsc_sched *q = qdisc_priv(sch);
 997         struct hfsc_class *cl;
 998
 999         list_for_each_entry(cl, &q->clhash[hfsc_hash(classid)], hlist) {
1000                 if (cl->classid == classid)
1001                         return cl;
1002         }
1003         return NULL;
1004 }
1005
1006 static void
1007 hfsc_change_rsc(struct hfsc_class *cl, struct tc_service_curve *rsc,
1008                 u64 cur_time)
1009 {
1010         sc2isc(rsc, &cl->cl_rsc);
1011         rtsc_init(&cl->cl_deadline, &cl->cl_rsc, cur_time, cl->cl_cumul);
1012         cl->cl_eligible = cl->cl_deadline;
1013         if (cl->cl_rsc.sm1 <= cl->cl_rsc.sm2) {
1014                 cl->cl_eligible.dx = 0;
1015                 cl->cl_eligible.dy = 0;
1016         }
1017         cl->cl_flags |= HFSC_RSC;
1018 }
1019
1020 static void
1021 hfsc_change_fsc(struct hfsc_class *cl, struct tc_service_curve *fsc)
1022 {
1023         sc2isc(fsc, &cl->cl_fsc);
1024         rtsc_init(&cl->cl_virtual, &cl->cl_fsc, cl->cl_vt, cl->cl_total);
1025         cl->cl_flags |= HFSC_FSC;
1026 }
1027
1028 static void
1029 hfsc_change_usc(struct hfsc_class *cl, struct tc_service_curve *usc,
1030                 u64 cur_time)
1031 {
1032         sc2isc(usc, &cl->cl_usc);
1033         rtsc_init(&cl->cl_ulimit, &cl->cl_usc, cur_time, cl->cl_total);
1034         cl->cl_flags |= HFSC_USC;
1035 }
1036
1037 static int
1038 hfsc_change_class(struct Qdisc *sch, u32 classid, u32 parentid,
1039                   struct rtattr **tca, unsigned long *arg)
1040 {
1041         struct hfsc_sched *q = qdisc_priv(sch);
1042         struct hfsc_class *cl = (struct hfsc_class *)*arg;
1043         struct hfsc_class *parent = NULL;
1044         struct rtattr *opt = tca[TCA_OPTIONS-1];
1045         struct rtattr *tb[TCA_HFSC_MAX];
1046         struct tc_service_curve *rsc = NULL, *fsc = NULL, *usc = NULL;
1047         u64 cur_time;
1048
1049         if (opt == NULL || rtattr_parse_nested(tb, TCA_HFSC_MAX, opt))
1050                 return -EINVAL;
1051
1052         if (tb[TCA_HFSC_RSC-1]) {
1053                 if (RTA_PAYLOAD(tb[TCA_HFSC_RSC-1]) < sizeof(*rsc))
1054                         return -EINVAL;
1055                 rsc = RTA_DATA(tb[TCA_HFSC_RSC-1]);
1056                 if (rsc->m1 == 0 && rsc->m2 == 0)
1057                         rsc = NULL;
1058         }
1059
1060         if (tb[TCA_HFSC_FSC-1]) {
1061                 if (RTA_PAYLOAD(tb[TCA_HFSC_FSC-1]) < sizeof(*fsc))
1062                         return -EINVAL;
1063                 fsc = RTA_DATA(tb[TCA_HFSC_FSC-1]);
1064                 if (fsc->m1 == 0 && fsc->m2 == 0)
1065                         fsc = NULL;
1066         }
1067
1068         if (tb[TCA_HFSC_USC-1]) {
1069                 if (RTA_PAYLOAD(tb[TCA_HFSC_USC-1]) < sizeof(*usc))
1070                         return -EINVAL;
1071                 usc = RTA_DATA(tb[TCA_HFSC_USC-1]);
1072                 if (usc->m1 == 0 && usc->m2 == 0)
1073                         usc = NULL;
1074         }
1075
1076         if (cl != NULL) {
1077                 if (parentid) {
1078                         if (cl->cl_parent && cl->cl_parent->classid != parentid)
1079                                 return -EINVAL;
1080                         if (cl->cl_parent == NULL && parentid != TC_H_ROOT)
1081                                 return -EINVAL;
1082                 }
1083                 PSCHED_GET_TIME(cur_time);
1084
1085                 sch_tree_lock(sch);
1086                 if (rsc != NULL)
1087                         hfsc_change_rsc(cl, rsc, cur_time);
1088                 if (fsc != NULL)
1089                         hfsc_change_fsc(cl, fsc);
1090                 if (usc != NULL)
1091                         hfsc_change_usc(cl, usc, cur_time);
1092
1093                 if (cl->qdisc->q.qlen != 0) {
1094                         if (cl->cl_flags & HFSC_RSC)
1095                                 update_ed(cl, qdisc_peek_len(cl->qdisc));
1096                         if (cl->cl_flags & HFSC_FSC)
1097                                 update_vf(cl, 0, cur_time);
1098                 }
1099                 sch_tree_unlock(sch);
1100
1101 #ifdef CONFIG_NET_ESTIMATOR
1102                 if (tca[TCA_RATE-1])
1103                         gen_replace_estimator(&cl->bstats, &cl->rate_est,
1104                                 cl->stats_lock, tca[TCA_RATE-1]);
1105 #endif
1106                 return 0;
1107         }
1108
1109         if (parentid == TC_H_ROOT)
1110                 return -EEXIST;
1111
1112         parent = &q->root;
1113         if (parentid) {
1114                 parent = hfsc_find_class(parentid, sch);
1115                 if (parent == NULL)
1116                         return -ENOENT;
1117         }
1118
1119         if (classid == 0 || TC_H_MAJ(classid ^ sch->handle) != 0)
1120                 return -EINVAL;
1121         if (hfsc_find_class(classid, sch))
1122                 return -EEXIST;
1123
1124         if (rsc == NULL && fsc == NULL)
1125                 return -EINVAL;
1126
1127         cl = kmalloc(sizeof(struct hfsc_class), GFP_KERNEL);
1128         if (cl == NULL)
1129                 return -ENOBUFS;
1130         memset(cl, 0, sizeof(struct hfsc_class));
1131
1132         if (rsc != NULL)
1133                 hfsc_change_rsc(cl, rsc, 0);
1134         if (fsc != NULL)
1135                 hfsc_change_fsc(cl, fsc);
1136         if (usc != NULL)
1137                 hfsc_change_usc(cl, usc, 0);
1138
1139         cl->refcnt    = 1;
1140         cl->classid   = classid;
1141         cl->sched     = q;
1142         cl->cl_parent = parent;
1143         cl->qdisc = qdisc_create_dflt(sch->dev, &pfifo_qdisc_ops);
1144         if (cl->qdisc == NULL)
1145                 cl->qdisc = &noop_qdisc;
1146         cl->stats_lock = &sch->dev->queue_lock;
1147         INIT_LIST_HEAD(&cl->children);
1148         cl->vt_tree = RB_ROOT;
1149         cl->cf_tree = RB_ROOT;
1150
1151         sch_tree_lock(sch);
1152         list_add_tail(&cl->hlist, &q->clhash[hfsc_hash(classid)]);
1153         list_add_tail(&cl->siblings, &parent->children);
1154         if (parent->level == 0)
1155                 hfsc_purge_queue(sch, parent);
1156         hfsc_adjust_levels(parent);
1157         cl->cl_pcvtoff = parent->cl_cvtoff;
1158         sch_tree_unlock(sch);
1159
1160 #ifdef CONFIG_NET_ESTIMATOR
1161         if (tca[TCA_RATE-1])
1162                 gen_new_estimator(&cl->bstats, &cl->rate_est,
1163                         cl->stats_lock, tca[TCA_RATE-1]);
1164 #endif
1165         *arg = (unsigned long)cl;
1166         return 0;
1167 }
1168
1169 static void
1170 hfsc_destroy_filters(struct tcf_proto **fl)
1171 {
1172         struct tcf_proto *tp;
1173
1174         while ((tp = *fl) != NULL) {
1175                 *fl = tp->next;
1176                 tcf_destroy(tp);
1177         }
1178 }
1179
1180 static void
1181 hfsc_destroy_class(struct Qdisc *sch, struct hfsc_class *cl)
1182 {
1183         struct hfsc_sched *q = qdisc_priv(sch);
1184
1185         hfsc_destroy_filters(&cl->filter_list);
1186         qdisc_destroy(cl->qdisc);
1187 #ifdef CONFIG_NET_ESTIMATOR
1188         gen_kill_estimator(&cl->bstats, &cl->rate_est);
1189 #endif
1190         if (cl != &q->root)
1191                 kfree(cl);
1192 }
1193
1194 static int
1195 hfsc_delete_class(struct Qdisc *sch, unsigned long arg)
1196 {
1197         struct hfsc_sched *q = qdisc_priv(sch);
1198         struct hfsc_class *cl = (struct hfsc_class *)arg;
1199
1200         if (cl->level > 0 || cl->filter_cnt > 0 || cl == &q->root)
1201                 return -EBUSY;
1202
1203         sch_tree_lock(sch);
1204
1205         list_del(&cl->hlist);
1206         list_del(&cl->siblings);
1207         hfsc_adjust_levels(cl->cl_parent);
1208         hfsc_purge_queue(sch, cl);
1209         if (--cl->refcnt == 0)
1210                 hfsc_destroy_class(sch, cl);
1211
1212         sch_tree_unlock(sch);
1213         return 0;
1214 }
1215
1216 static struct hfsc_class *
1217 hfsc_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr)
1218 {
1219         struct hfsc_sched *q = qdisc_priv(sch);
1220         struct hfsc_class *cl;
1221         struct tcf_result res;
1222         struct tcf_proto *tcf;
1223         int result;
1224
1225         if (TC_H_MAJ(skb->priority ^ sch->handle) == 0 &&
1226             (cl = hfsc_find_class(skb->priority, sch)) != NULL)
1227                 if (cl->level == 0)
1228                         return cl;
1229
1230         *qerr = NET_XMIT_BYPASS;
1231         tcf = q->root.filter_list;
1232         while (tcf && (result = tc_classify(skb, tcf, &res)) >= 0) {
1233 #ifdef CONFIG_NET_CLS_ACT
1234                 switch (result) {
1235                 case TC_ACT_QUEUED:
1236                 case TC_ACT_STOLEN:
1237                         *qerr = NET_XMIT_SUCCESS;
1238                 case TC_ACT_SHOT:
1239                         return NULL;
1240                 }
1241 #elif defined(CONFIG_NET_CLS_POLICE)
1242                 if (result == TC_POLICE_SHOT)
1243                         return NULL;
1244 #endif
1245                 if ((cl = (struct hfsc_class *)res.class) == NULL) {
1246                         if ((cl = hfsc_find_class(res.classid, sch)) == NULL)
1247                                 break; /* filter selected invalid classid */
1248                 }
1249
1250                 if (cl->level == 0)
1251                         return cl; /* hit leaf class */
1252
1253                 /* apply inner filter chain */
1254                 tcf = cl->filter_list;
1255         }
1256
1257         /* classification failed, try default class */
1258         cl = hfsc_find_class(TC_H_MAKE(TC_H_MAJ(sch->handle), q->defcls), sch);
1259         if (cl == NULL || cl->level > 0)
1260                 return NULL;
1261
1262         return cl;
1263 }
1264
1265 static int
1266 hfsc_graft_class(struct Qdisc *sch, unsigned long arg, struct Qdisc *new,
1267                  struct Qdisc **old)
1268 {
1269         struct hfsc_class *cl = (struct hfsc_class *)arg;
1270
1271         if (cl == NULL)
1272                 return -ENOENT;
1273         if (cl->level > 0)
1274                 return -EINVAL;
1275         if (new == NULL) {
1276                 new = qdisc_create_dflt(sch->dev, &pfifo_qdisc_ops);
1277                 if (new == NULL)
1278                         new = &noop_qdisc;
1279         }
1280
1281         sch_tree_lock(sch);
1282         hfsc_purge_queue(sch, cl);
1283         *old = xchg(&cl->qdisc, new);
1284         sch_tree_unlock(sch);
1285         return 0;
1286 }
1287
1288 static struct Qdisc *
1289 hfsc_class_leaf(struct Qdisc *sch, unsigned long arg)
1290 {
1291         struct hfsc_class *cl = (struct hfsc_class *)arg;
1292
1293         if (cl != NULL && cl->level == 0)
1294                 return cl->qdisc;
1295
1296         return NULL;
1297 }
1298
1299 static unsigned long
1300 hfsc_get_class(struct Qdisc *sch, u32 classid)
1301 {
1302         struct hfsc_class *cl = hfsc_find_class(classid, sch);
1303
1304         if (cl != NULL)
1305                 cl->refcnt++;
1306
1307         return (unsigned long)cl;
1308 }
1309
1310 static void
1311 hfsc_put_class(struct Qdisc *sch, unsigned long arg)
1312 {
1313         struct hfsc_class *cl = (struct hfsc_class *)arg;
1314
1315         if (--cl->refcnt == 0)
1316                 hfsc_destroy_class(sch, cl);
1317 }
1318
1319 static unsigned long
1320 hfsc_bind_tcf(struct Qdisc *sch, unsigned long parent, u32 classid)
1321 {
1322         struct hfsc_class *p = (struct hfsc_class *)parent;
1323         struct hfsc_class *cl = hfsc_find_class(classid, sch);
1324
1325         if (cl != NULL) {
1326                 if (p != NULL && p->level <= cl->level)
1327                         return 0;
1328                 cl->filter_cnt++;
1329         }
1330
1331         return (unsigned long)cl;
1332 }
1333
1334 static void
1335 hfsc_unbind_tcf(struct Qdisc *sch, unsigned long arg)
1336 {
1337         struct hfsc_class *cl = (struct hfsc_class *)arg;
1338
1339         cl->filter_cnt--;
1340 }
1341
1342 static struct tcf_proto **
1343 hfsc_tcf_chain(struct Qdisc *sch, unsigned long arg)
1344 {
1345         struct hfsc_sched *q = qdisc_priv(sch);
1346         struct hfsc_class *cl = (struct hfsc_class *)arg;
1347
1348         if (cl == NULL)
1349                 cl = &q->root;
1350
1351         return &cl->filter_list;
1352 }
1353
1354 static int
1355 hfsc_dump_sc(struct sk_buff *skb, int attr, struct internal_sc *sc)
1356 {
1357         struct tc_service_curve tsc;
1358
1359         tsc.m1 = sm2m(sc->sm1);
1360         tsc.d  = dx2d(sc->dx);
1361         tsc.m2 = sm2m(sc->sm2);
1362         RTA_PUT(skb, attr, sizeof(tsc), &tsc);
1363
1364         return skb->len;
1365
1366  rtattr_failure:
1367         return -1;
1368 }
1369
1370 static inline int
1371 hfsc_dump_curves(struct sk_buff *skb, struct hfsc_class *cl)
1372 {
1373         if ((cl->cl_flags & HFSC_RSC) &&
1374             (hfsc_dump_sc(skb, TCA_HFSC_RSC, &cl->cl_rsc) < 0))
1375                 goto rtattr_failure;
1376
1377         if ((cl->cl_flags & HFSC_FSC) &&
1378             (hfsc_dump_sc(skb, TCA_HFSC_FSC, &cl->cl_fsc) < 0))
1379                 goto rtattr_failure;
1380
1381         if ((cl->cl_flags & HFSC_USC) &&
1382             (hfsc_dump_sc(skb, TCA_HFSC_USC, &cl->cl_usc) < 0))
1383                 goto rtattr_failure;
1384
1385         return skb->len;
1386
1387  rtattr_failure:
1388         return -1;
1389 }
1390
1391 static int
1392 hfsc_dump_class(struct Qdisc *sch, unsigned long arg, struct sk_buff *skb,
1393                 struct tcmsg *tcm)
1394 {
1395         struct hfsc_class *cl = (struct hfsc_class *)arg;
1396         unsigned char *b = skb->tail;
1397         struct rtattr *rta = (struct rtattr *)b;
1398
1399         tcm->tcm_parent = cl->cl_parent ? cl->cl_parent->classid : TC_H_ROOT;
1400         tcm->tcm_handle = cl->classid;
1401         if (cl->level == 0)
1402                 tcm->tcm_info = cl->qdisc->handle;
1403
1404         RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
1405         if (hfsc_dump_curves(skb, cl) < 0)
1406                 goto rtattr_failure;
1407         rta->rta_len = skb->tail - b;
1408         return skb->len;
1409
1410  rtattr_failure:
1411         skb_trim(skb, b - skb->data);
1412         return -1;
1413 }
1414
1415 static int
1416 hfsc_dump_class_stats(struct Qdisc *sch, unsigned long arg,
1417         struct gnet_dump *d)
1418 {
1419         struct hfsc_class *cl = (struct hfsc_class *)arg;
1420         struct tc_hfsc_stats xstats;
1421
1422         cl->qstats.qlen = cl->qdisc->q.qlen;
1423         xstats.level   = cl->level;
1424         xstats.period  = cl->cl_vtperiod;
1425         xstats.work    = cl->cl_total;
1426         xstats.rtwork  = cl->cl_cumul;
1427
1428         if (gnet_stats_copy_basic(d, &cl->bstats) < 0 ||
1429 #ifdef CONFIG_NET_ESTIMATOR
1430             gnet_stats_copy_rate_est(d, &cl->rate_est) < 0 ||
1431 #endif
1432             gnet_stats_copy_queue(d, &cl->qstats) < 0)
1433                 return -1;
1434
1435         return gnet_stats_copy_app(d, &xstats, sizeof(xstats));
1436 }
1437
1438
1439
1440 static void
1441 hfsc_walk(struct Qdisc *sch, struct qdisc_walker *arg)
1442 {
1443         struct hfsc_sched *q = qdisc_priv(sch);
1444         struct hfsc_class *cl;
1445         unsigned int i;
1446
1447         if (arg->stop)
1448                 return;
1449
1450         for (i = 0; i < HFSC_HSIZE; i++) {
1451                 list_for_each_entry(cl, &q->clhash[i], hlist) {
1452                         if (arg->count < arg->skip) {
1453                                 arg->count++;
1454                                 continue;
1455                         }
1456                         if (arg->fn(sch, (unsigned long)cl, arg) < 0) {
1457                                 arg->stop = 1;
1458                                 return;
1459                         }
1460                         arg->count++;
1461                 }
1462         }
1463 }
1464
1465 static void
1466 hfsc_watchdog(unsigned long arg)
1467 {
1468         struct Qdisc *sch = (struct Qdisc *)arg;
1469
1470         sch->flags &= ~TCQ_F_THROTTLED;
1471         netif_schedule(sch->dev);
1472 }
1473
1474 static void
1475 hfsc_schedule_watchdog(struct Qdisc *sch, u64 cur_time)
1476 {
1477         struct hfsc_sched *q = qdisc_priv(sch);
1478         struct hfsc_class *cl;
1479         u64 next_time = 0;
1480         long delay;
1481
1482         if ((cl = eltree_get_minel(q)) != NULL)
1483                 next_time = cl->cl_e;
1484         if (q->root.cl_cfmin != 0) {
1485                 if (next_time == 0 || next_time > q->root.cl_cfmin)
1486                         next_time = q->root.cl_cfmin;
1487         }
1488         ASSERT(next_time != 0);
1489         delay = next_time - cur_time;
1490         delay = PSCHED_US2JIFFIE(delay);
1491
1492         sch->flags |= TCQ_F_THROTTLED;
1493         mod_timer(&q->wd_timer, jiffies + delay);
1494 }
1495
1496 static int
1497 hfsc_init_qdisc(struct Qdisc *sch, struct rtattr *opt)
1498 {
1499         struct hfsc_sched *q = qdisc_priv(sch);
1500         struct tc_hfsc_qopt *qopt;
1501         unsigned int i;
1502
1503         if (opt == NULL || RTA_PAYLOAD(opt) < sizeof(*qopt))
1504                 return -EINVAL;
1505         qopt = RTA_DATA(opt);
1506
1507         sch->stats_lock = &sch->dev->queue_lock;
1508
1509         q->defcls = qopt->defcls;
1510         for (i = 0; i < HFSC_HSIZE; i++)
1511                 INIT_LIST_HEAD(&q->clhash[i]);
1512         q->eligible = RB_ROOT;
1513         INIT_LIST_HEAD(&q->droplist);
1514         skb_queue_head_init(&q->requeue);
1515
1516         q->root.refcnt  = 1;
1517         q->root.classid = sch->handle;
1518         q->root.sched   = q;
1519         q->root.qdisc = qdisc_create_dflt(sch->dev, &pfifo_qdisc_ops);
1520         if (q->root.qdisc == NULL)
1521                 q->root.qdisc = &noop_qdisc;
1522         q->root.stats_lock = &sch->dev->queue_lock;
1523         INIT_LIST_HEAD(&q->root.children);
1524         q->root.vt_tree = RB_ROOT;
1525         q->root.cf_tree = RB_ROOT;
1526
1527         list_add(&q->root.hlist, &q->clhash[hfsc_hash(q->root.classid)]);
1528
1529         init_timer(&q->wd_timer);
1530         q->wd_timer.function = hfsc_watchdog;
1531         q->wd_timer.data = (unsigned long)sch;
1532
1533         return 0;
1534 }
1535
1536 static int
1537 hfsc_change_qdisc(struct Qdisc *sch, struct rtattr *opt)
1538 {
1539         struct hfsc_sched *q = qdisc_priv(sch);
1540         struct tc_hfsc_qopt *qopt;
1541
1542         if (opt == NULL || RTA_PAYLOAD(opt) < sizeof(*qopt))
1543                 return -EINVAL;
1544         qopt = RTA_DATA(opt);
1545
1546         sch_tree_lock(sch);
1547         q->defcls = qopt->defcls;
1548         sch_tree_unlock(sch);
1549
1550         return 0;
1551 }
1552
1553 static void
1554 hfsc_reset_class(struct hfsc_class *cl)
1555 {
1556         cl->cl_total        = 0;
1557         cl->cl_cumul        = 0;
1558         cl->cl_d            = 0;
1559         cl->cl_e            = 0;
1560         cl->cl_vt           = 0;
1561         cl->cl_vtadj        = 0;
1562         cl->cl_vtoff        = 0;
1563         cl->cl_cvtmin       = 0;
1564         cl->cl_cvtmax       = 0;
1565         cl->cl_cvtoff       = 0;
1566         cl->cl_pcvtoff      = 0;
1567         cl->cl_vtperiod     = 0;
1568         cl->cl_parentperiod = 0;
1569         cl->cl_f            = 0;
1570         cl->cl_myf          = 0;
1571         cl->cl_myfadj       = 0;
1572         cl->cl_cfmin        = 0;
1573         cl->cl_nactive      = 0;
1574
1575         cl->vt_tree = RB_ROOT;
1576         cl->cf_tree = RB_ROOT;
1577         qdisc_reset(cl->qdisc);
1578
1579         if (cl->cl_flags & HFSC_RSC)
1580                 rtsc_init(&cl->cl_deadline, &cl->cl_rsc, 0, 0);
1581         if (cl->cl_flags & HFSC_FSC)
1582                 rtsc_init(&cl->cl_virtual, &cl->cl_fsc, 0, 0);
1583         if (cl->cl_flags & HFSC_USC)
1584                 rtsc_init(&cl->cl_ulimit, &cl->cl_usc, 0, 0);
1585 }
1586
1587 static void
1588 hfsc_reset_qdisc(struct Qdisc *sch)
1589 {
1590         struct hfsc_sched *q = qdisc_priv(sch);
1591         struct hfsc_class *cl;
1592         unsigned int i;
1593
1594         for (i = 0; i < HFSC_HSIZE; i++) {
1595                 list_for_each_entry(cl, &q->clhash[i], hlist)
1596                         hfsc_reset_class(cl);
1597         }
1598         __skb_queue_purge(&q->requeue);
1599         q->eligible = RB_ROOT;
1600         INIT_LIST_HEAD(&q->droplist);
1601         del_timer(&q->wd_timer);
1602         sch->flags &= ~TCQ_F_THROTTLED;
1603         sch->q.qlen = 0;
1604 }
1605
1606 static void
1607 hfsc_destroy_qdisc(struct Qdisc *sch)
1608 {
1609         struct hfsc_sched *q = qdisc_priv(sch);
1610         struct hfsc_class *cl, *next;
1611         unsigned int i;
1612
1613         for (i = 0; i < HFSC_HSIZE; i++) {
1614                 list_for_each_entry_safe(cl, next, &q->clhash[i], hlist)
1615                         hfsc_destroy_class(sch, cl);
1616         }
1617         __skb_queue_purge(&q->requeue);
1618         del_timer(&q->wd_timer);
1619 }
1620
1621 static int
1622 hfsc_dump_qdisc(struct Qdisc *sch, struct sk_buff *skb)
1623 {
1624         struct hfsc_sched *q = qdisc_priv(sch);
1625         unsigned char *b = skb->tail;
1626         struct tc_hfsc_qopt qopt;
1627
1628         qopt.defcls = q->defcls;
1629         RTA_PUT(skb, TCA_OPTIONS, sizeof(qopt), &qopt);
1630         return skb->len;
1631
1632  rtattr_failure:
1633         skb_trim(skb, b - skb->data);
1634         return -1;
1635 }
1636
1637 static int
1638 hfsc_enqueue(struct sk_buff *skb, struct Qdisc *sch)
1639 {
1640         struct hfsc_class *cl;
1641         unsigned int len;
1642         int err;
1643
1644         cl = hfsc_classify(skb, sch, &err);
1645         if (cl == NULL) {
1646                 if (err == NET_XMIT_BYPASS)
1647                         sch->qstats.drops++;
1648                 kfree_skb(skb);
1649                 return err;
1650         }
1651
1652         len = skb->len;
1653         err = cl->qdisc->enqueue(skb, cl->qdisc);
1654         if (unlikely(err != NET_XMIT_SUCCESS)) {
1655                 cl->qstats.drops++;
1656                 sch->qstats.drops++;
1657                 return err;
1658         }
1659
1660         if (cl->qdisc->q.qlen == 1)
1661                 set_active(cl, len);
1662
1663         cl->bstats.packets++;
1664         cl->bstats.bytes += len;
1665         sch->bstats.packets++;
1666         sch->bstats.bytes += len;
1667         sch->q.qlen++;
1668
1669         return NET_XMIT_SUCCESS;
1670 }
1671
1672 static struct sk_buff *
1673 hfsc_dequeue(struct Qdisc *sch)
1674 {
1675         struct hfsc_sched *q = qdisc_priv(sch);
1676         struct hfsc_class *cl;
1677         struct sk_buff *skb;
1678         u64 cur_time;
1679         unsigned int next_len;
1680         int realtime = 0;
1681
1682         if (sch->q.qlen == 0)
1683                 return NULL;
1684         if ((skb = __skb_dequeue(&q->requeue)))
1685                 goto out;
1686
1687         PSCHED_GET_TIME(cur_time);
1688
1689         /*
1690          * if there are eligible classes, use real-time criteria.
1691          * find the class with the minimum deadline among
1692          * the eligible classes.
1693          */
1694         if ((cl = eltree_get_mindl(q, cur_time)) != NULL) {
1695                 realtime = 1;
1696         } else {
1697                 /*
1698                  * use link-sharing criteria
1699                  * get the class with the minimum vt in the hierarchy
1700                  */
1701                 cl = vttree_get_minvt(&q->root, cur_time);
1702                 if (cl == NULL) {
1703                         sch->qstats.overlimits++;
1704                         hfsc_schedule_watchdog(sch, cur_time);
1705                         return NULL;
1706                 }
1707         }
1708
1709         skb = cl->qdisc->dequeue(cl->qdisc);
1710         if (skb == NULL) {
1711                 if (net_ratelimit())
1712                         printk("HFSC: Non-work-conserving qdisc ?\n");
1713                 return NULL;
1714         }
1715
1716         update_vf(cl, skb->len, cur_time);
1717         if (realtime)
1718                 cl->cl_cumul += skb->len;
1719
1720         if (cl->qdisc->q.qlen != 0) {
1721                 if (cl->cl_flags & HFSC_RSC) {
1722                         /* update ed */
1723                         next_len = qdisc_peek_len(cl->qdisc);
1724                         if (realtime)
1725                                 update_ed(cl, next_len);
1726                         else
1727                                 update_d(cl, next_len);
1728                 }
1729         } else {
1730                 /* the class becomes passive */
1731                 set_passive(cl);
1732         }
1733
1734  out:
1735         sch->flags &= ~TCQ_F_THROTTLED;
1736         sch->q.qlen--;
1737
1738         return skb;
1739 }
1740
1741 static int
1742 hfsc_requeue(struct sk_buff *skb, struct Qdisc *sch)
1743 {
1744         struct hfsc_sched *q = qdisc_priv(sch);
1745
1746         __skb_queue_head(&q->requeue, skb);
1747         sch->q.qlen++;
1748         sch->qstats.requeues++;
1749         return NET_XMIT_SUCCESS;
1750 }
1751
1752 static unsigned int
1753 hfsc_drop(struct Qdisc *sch)
1754 {
1755         struct hfsc_sched *q = qdisc_priv(sch);
1756         struct hfsc_class *cl;
1757         unsigned int len;
1758
1759         list_for_each_entry(cl, &q->droplist, dlist) {
1760                 if (cl->qdisc->ops->drop != NULL &&
1761                     (len = cl->qdisc->ops->drop(cl->qdisc)) > 0) {
1762                         if (cl->qdisc->q.qlen == 0) {
1763                                 update_vf(cl, 0, 0);
1764                                 set_passive(cl);
1765                         } else {
1766                                 list_move_tail(&cl->dlist, &q->droplist);
1767                         }
1768                         cl->qstats.drops++;
1769                         sch->qstats.drops++;
1770                         sch->q.qlen--;
1771                         return len;
1772                 }
1773         }
1774         return 0;
1775 }
1776
1777 static struct Qdisc_class_ops hfsc_class_ops = {
1778         .change         = hfsc_change_class,
1779         .delete         = hfsc_delete_class,
1780         .graft          = hfsc_graft_class,
1781         .leaf           = hfsc_class_leaf,
1782         .get            = hfsc_get_class,
1783         .put            = hfsc_put_class,
1784         .bind_tcf       = hfsc_bind_tcf,
1785         .unbind_tcf     = hfsc_unbind_tcf,
1786         .tcf_chain      = hfsc_tcf_chain,
1787         .dump           = hfsc_dump_class,
1788         .dump_stats     = hfsc_dump_class_stats,
1789         .walk           = hfsc_walk
1790 };
1791
1792 static struct Qdisc_ops hfsc_qdisc_ops = {
1793         .id             = "hfsc",
1794         .init           = hfsc_init_qdisc,
1795         .change         = hfsc_change_qdisc,
1796         .reset          = hfsc_reset_qdisc,
1797         .destroy        = hfsc_destroy_qdisc,
1798         .dump           = hfsc_dump_qdisc,
1799         .enqueue        = hfsc_enqueue,
1800         .dequeue        = hfsc_dequeue,
1801         .requeue        = hfsc_requeue,
1802         .drop           = hfsc_drop,
1803         .cl_ops         = &hfsc_class_ops,
1804         .priv_size      = sizeof(struct hfsc_sched),
1805         .owner          = THIS_MODULE
1806 };
1807
1808 static int __init
1809 hfsc_init(void)
1810 {
1811         return register_qdisc(&hfsc_qdisc_ops);
1812 }
1813
1814 static void __exit
1815 hfsc_cleanup(void)
1816 {
1817         unregister_qdisc(&hfsc_qdisc_ops);
1818 }
1819
1820 MODULE_LICENSE("GPL");
1821 module_init(hfsc_init);
1822 module_exit(hfsc_cleanup);