linux/net/sched/sch_hfsc.c
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   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/module.h>
  54#include <linux/types.h>
  55#include <linux/errno.h>
  56#include <linux/compiler.h>
  57#include <linux/spinlock.h>
  58#include <linux/skbuff.h>
  59#include <linux/string.h>
  60#include <linux/slab.h>
  61#include <linux/list.h>
  62#include <linux/rbtree.h>
  63#include <linux/init.h>
  64#include <linux/rtnetlink.h>
  65#include <linux/pkt_sched.h>
  66#include <net/netlink.h>
  67#include <net/pkt_sched.h>
  68#include <net/pkt_cls.h>
  69#include <asm/div64.h>
  70
  71/*
  72 * kernel internal service curve representation:
  73 *   coordinates are given by 64 bit unsigned integers.
  74 *   x-axis: unit is clock count.
  75 *   y-axis: unit is byte.
  76 *
  77 *   The service curve parameters are converted to the internal
  78 *   representation. The slope values are scaled to avoid overflow.
  79 *   the inverse slope values as well as the y-projection of the 1st
  80 *   segment are kept in order to to avoid 64-bit divide operations
  81 *   that are expensive on 32-bit architectures.
  82 */
  83
  84struct internal_sc
  85{
  86        u64     sm1;    /* scaled slope of the 1st segment */
  87        u64     ism1;   /* scaled inverse-slope of the 1st segment */
  88        u64     dx;     /* the x-projection of the 1st segment */
  89        u64     dy;     /* the y-projection of the 1st segment */
  90        u64     sm2;    /* scaled slope of the 2nd segment */
  91        u64     ism2;   /* scaled inverse-slope of the 2nd segment */
  92};
  93
  94/* runtime service curve */
  95struct runtime_sc
  96{
  97        u64     x;      /* current starting position on x-axis */
  98        u64     y;      /* current starting position on y-axis */
  99        u64     sm1;    /* scaled slope of the 1st segment */
 100        u64     ism1;   /* scaled inverse-slope of the 1st segment */
 101        u64     dx;     /* the x-projection of the 1st segment */
 102        u64     dy;     /* the y-projection of the 1st segment */
 103        u64     sm2;    /* scaled slope of the 2nd segment */
 104        u64     ism2;   /* scaled inverse-slope of the 2nd segment */
 105};
 106
 107enum hfsc_class_flags
 108{
 109        HFSC_RSC = 0x1,
 110        HFSC_FSC = 0x2,
 111        HFSC_USC = 0x4
 112};
 113
 114struct hfsc_class
 115{
 116        struct Qdisc_class_common cl_common;
 117        unsigned int    refcnt;         /* usage count */
 118
 119        struct gnet_stats_basic bstats;
 120        struct gnet_stats_queue qstats;
 121        struct gnet_stats_rate_est rate_est;
 122        unsigned int    level;          /* class level in hierarchy */
 123        struct tcf_proto *filter_list;  /* filter list */
 124        unsigned int    filter_cnt;     /* filter count */
 125
 126        struct hfsc_sched *sched;       /* scheduler data */
 127        struct hfsc_class *cl_parent;   /* parent class */
 128        struct list_head siblings;      /* sibling classes */
 129        struct list_head children;      /* child classes */
 130        struct Qdisc    *qdisc;         /* leaf qdisc */
 131
 132        struct rb_node el_node;         /* qdisc's eligible tree member */
 133        struct rb_root vt_tree;         /* active children sorted by cl_vt */
 134        struct rb_node vt_node;         /* parent's vt_tree member */
 135        struct rb_root cf_tree;         /* active children sorted by cl_f */
 136        struct rb_node cf_node;         /* parent's cf_heap member */
 137        struct list_head dlist;         /* drop list member */
 138
 139        u64     cl_total;               /* total work in bytes */
 140        u64     cl_cumul;               /* cumulative work in bytes done by
 141                                           real-time criteria */
 142
 143        u64     cl_d;                   /* deadline*/
 144        u64     cl_e;                   /* eligible time */
 145        u64     cl_vt;                  /* virtual time */
 146        u64     cl_f;                   /* time when this class will fit for
 147                                           link-sharing, max(myf, cfmin) */
 148        u64     cl_myf;                 /* my fit-time (calculated from this
 149                                           class's own upperlimit curve) */
 150        u64     cl_myfadj;              /* my fit-time adjustment (to cancel
 151                                           history dependence) */
 152        u64     cl_cfmin;               /* earliest children's fit-time (used
 153                                           with cl_myf to obtain cl_f) */
 154        u64     cl_cvtmin;              /* minimal virtual time among the
 155                                           children fit for link-sharing
 156                                           (monotonic within a period) */
 157        u64     cl_vtadj;               /* intra-period cumulative vt
 158                                           adjustment */
 159        u64     cl_vtoff;               /* inter-period cumulative vt offset */
 160        u64     cl_cvtmax;              /* max child's vt in the last period */
 161        u64     cl_cvtoff;              /* cumulative cvtmax of all periods */
 162        u64     cl_pcvtoff;             /* parent's cvtoff at initialization
 163                                           time */
 164
 165        struct internal_sc cl_rsc;      /* internal real-time service curve */
 166        struct internal_sc cl_fsc;      /* internal fair service curve */
 167        struct internal_sc cl_usc;      /* internal upperlimit service curve */
 168        struct runtime_sc cl_deadline;  /* deadline curve */
 169        struct runtime_sc cl_eligible;  /* eligible curve */
 170        struct runtime_sc cl_virtual;   /* virtual curve */
 171        struct runtime_sc cl_ulimit;    /* upperlimit curve */
 172
 173        unsigned long   cl_flags;       /* which curves are valid */
 174        unsigned long   cl_vtperiod;    /* vt period sequence number */
 175        unsigned long   cl_parentperiod;/* parent's vt period sequence number*/
 176        unsigned long   cl_nactive;     /* number of active children */
 177};
 178
 179struct hfsc_sched
 180{
 181        u16     defcls;                         /* default class id */
 182        struct hfsc_class root;                 /* root class */
 183        struct Qdisc_class_hash clhash;         /* class hash */
 184        struct rb_root eligible;                /* eligible tree */
 185        struct list_head droplist;              /* active leaf class list (for
 186                                                   dropping) */
 187        struct qdisc_watchdog watchdog;         /* watchdog timer */
 188};
 189
 190#define HT_INFINITY     0xffffffffffffffffULL   /* infinite time value */
 191
 192
 193/*
 194 * eligible tree holds backlogged classes being sorted by their eligible times.
 195 * there is one eligible tree per hfsc instance.
 196 */
 197
 198static void
 199eltree_insert(struct hfsc_class *cl)
 200{
 201        struct rb_node **p = &cl->sched->eligible.rb_node;
 202        struct rb_node *parent = NULL;
 203        struct hfsc_class *cl1;
 204
 205        while (*p != NULL) {
 206                parent = *p;
 207                cl1 = rb_entry(parent, struct hfsc_class, el_node);
 208                if (cl->cl_e >= cl1->cl_e)
 209                        p = &parent->rb_right;
 210                else
 211                        p = &parent->rb_left;
 212        }
 213        rb_link_node(&cl->el_node, parent, p);
 214        rb_insert_color(&cl->el_node, &cl->sched->eligible);
 215}
 216
 217static inline void
 218eltree_remove(struct hfsc_class *cl)
 219{
 220        rb_erase(&cl->el_node, &cl->sched->eligible);
 221}
 222
 223static inline void
 224eltree_update(struct hfsc_class *cl)
 225{
 226        eltree_remove(cl);
 227        eltree_insert(cl);
 228}
 229
 230/* find the class with the minimum deadline among the eligible classes */
 231static inline struct hfsc_class *
 232eltree_get_mindl(struct hfsc_sched *q, u64 cur_time)
 233{
 234        struct hfsc_class *p, *cl = NULL;
 235        struct rb_node *n;
 236
 237        for (n = rb_first(&q->eligible); n != NULL; n = rb_next(n)) {
 238                p = rb_entry(n, struct hfsc_class, el_node);
 239                if (p->cl_e > cur_time)
 240                        break;
 241                if (cl == NULL || p->cl_d < cl->cl_d)
 242                        cl = p;
 243        }
 244        return cl;
 245}
 246
 247/* find the class with minimum eligible time among the eligible classes */
 248static inline struct hfsc_class *
 249eltree_get_minel(struct hfsc_sched *q)
 250{
 251        struct rb_node *n;
 252
 253        n = rb_first(&q->eligible);
 254        if (n == NULL)
 255                return NULL;
 256        return rb_entry(n, struct hfsc_class, el_node);
 257}
 258
 259/*
 260 * vttree holds holds backlogged child classes being sorted by their virtual
 261 * time. each intermediate class has one vttree.
 262 */
 263static void
 264vttree_insert(struct hfsc_class *cl)
 265{
 266        struct rb_node **p = &cl->cl_parent->vt_tree.rb_node;
 267        struct rb_node *parent = NULL;
 268        struct hfsc_class *cl1;
 269
 270        while (*p != NULL) {
 271                parent = *p;
 272                cl1 = rb_entry(parent, struct hfsc_class, vt_node);
 273                if (cl->cl_vt >= cl1->cl_vt)
 274                        p = &parent->rb_right;
 275                else
 276                        p = &parent->rb_left;
 277        }
 278        rb_link_node(&cl->vt_node, parent, p);
 279        rb_insert_color(&cl->vt_node, &cl->cl_parent->vt_tree);
 280}
 281
 282static inline void
 283vttree_remove(struct hfsc_class *cl)
 284{
 285        rb_erase(&cl->vt_node, &cl->cl_parent->vt_tree);
 286}
 287
 288static inline void
 289vttree_update(struct hfsc_class *cl)
 290{
 291        vttree_remove(cl);
 292        vttree_insert(cl);
 293}
 294
 295static inline struct hfsc_class *
 296vttree_firstfit(struct hfsc_class *cl, u64 cur_time)
 297{
 298        struct hfsc_class *p;
 299        struct rb_node *n;
 300
 301        for (n = rb_first(&cl->vt_tree); n != NULL; n = rb_next(n)) {
 302                p = rb_entry(n, struct hfsc_class, vt_node);
 303                if (p->cl_f <= cur_time)
 304                        return p;
 305        }
 306        return NULL;
 307}
 308
 309/*
 310 * get the leaf class with the minimum vt in the hierarchy
 311 */
 312static struct hfsc_class *
 313vttree_get_minvt(struct hfsc_class *cl, u64 cur_time)
 314{
 315        /* if root-class's cfmin is bigger than cur_time nothing to do */
 316        if (cl->cl_cfmin > cur_time)
 317                return NULL;
 318
 319        while (cl->level > 0) {
 320                cl = vttree_firstfit(cl, cur_time);
 321                if (cl == NULL)
 322                        return NULL;
 323                /*
 324                 * update parent's cl_cvtmin.
 325                 */
 326                if (cl->cl_parent->cl_cvtmin < cl->cl_vt)
 327                        cl->cl_parent->cl_cvtmin = cl->cl_vt;
 328        }
 329        return cl;
 330}
 331
 332static void
 333cftree_insert(struct hfsc_class *cl)
 334{
 335        struct rb_node **p = &cl->cl_parent->cf_tree.rb_node;
 336        struct rb_node *parent = NULL;
 337        struct hfsc_class *cl1;
 338
 339        while (*p != NULL) {
 340                parent = *p;
 341                cl1 = rb_entry(parent, struct hfsc_class, cf_node);
 342                if (cl->cl_f >= cl1->cl_f)
 343                        p = &parent->rb_right;
 344                else
 345                        p = &parent->rb_left;
 346        }
 347        rb_link_node(&cl->cf_node, parent, p);
 348        rb_insert_color(&cl->cf_node, &cl->cl_parent->cf_tree);
 349}
 350
 351static inline void
 352cftree_remove(struct hfsc_class *cl)
 353{
 354        rb_erase(&cl->cf_node, &cl->cl_parent->cf_tree);
 355}
 356
 357static inline void
 358cftree_update(struct hfsc_class *cl)
 359{
 360        cftree_remove(cl);
 361        cftree_insert(cl);
 362}
 363
 364/*
 365 * service curve support functions
 366 *
 367 *  external service curve parameters
 368 *      m: bps
 369 *      d: us
 370 *  internal service curve parameters
 371 *      sm: (bytes/psched_us) << SM_SHIFT
 372 *      ism: (psched_us/byte) << ISM_SHIFT
 373 *      dx: psched_us
 374 *
 375 * The clock source resolution with ktime is 1.024us.
 376 *
 377 * sm and ism are scaled in order to keep effective digits.
 378 * SM_SHIFT and ISM_SHIFT are selected to keep at least 4 effective
 379 * digits in decimal using the following table.
 380 *
 381 *  bits/sec      100Kbps     1Mbps     10Mbps     100Mbps    1Gbps
 382 *  ------------+-------------------------------------------------------
 383 *  bytes/1.024us 12.8e-3    128e-3     1280e-3    12800e-3   128000e-3
 384 *
 385 *  1.024us/byte  78.125     7.8125     0.78125    0.078125   0.0078125
 386 */
 387#define SM_SHIFT        20
 388#define ISM_SHIFT       18
 389
 390#define SM_MASK         ((1ULL << SM_SHIFT) - 1)
 391#define ISM_MASK        ((1ULL << ISM_SHIFT) - 1)
 392
 393static inline u64
 394seg_x2y(u64 x, u64 sm)
 395{
 396        u64 y;
 397
 398        /*
 399         * compute
 400         *      y = x * sm >> SM_SHIFT
 401         * but divide it for the upper and lower bits to avoid overflow
 402         */
 403        y = (x >> SM_SHIFT) * sm + (((x & SM_MASK) * sm) >> SM_SHIFT);
 404        return y;
 405}
 406
 407static inline u64
 408seg_y2x(u64 y, u64 ism)
 409{
 410        u64 x;
 411
 412        if (y == 0)
 413                x = 0;
 414        else if (ism == HT_INFINITY)
 415                x = HT_INFINITY;
 416        else {
 417                x = (y >> ISM_SHIFT) * ism
 418                    + (((y & ISM_MASK) * ism) >> ISM_SHIFT);
 419        }
 420        return x;
 421}
 422
 423/* Convert m (bps) into sm (bytes/psched us) */
 424static u64
 425m2sm(u32 m)
 426{
 427        u64 sm;
 428
 429        sm = ((u64)m << SM_SHIFT);
 430        sm += PSCHED_TICKS_PER_SEC - 1;
 431        do_div(sm, PSCHED_TICKS_PER_SEC);
 432        return sm;
 433}
 434
 435/* convert m (bps) into ism (psched us/byte) */
 436static u64
 437m2ism(u32 m)
 438{
 439        u64 ism;
 440
 441        if (m == 0)
 442                ism = HT_INFINITY;
 443        else {
 444                ism = ((u64)PSCHED_TICKS_PER_SEC << ISM_SHIFT);
 445                ism += m - 1;
 446                do_div(ism, m);
 447        }
 448        return ism;
 449}
 450
 451/* convert d (us) into dx (psched us) */
 452static u64
 453d2dx(u32 d)
 454{
 455        u64 dx;
 456
 457        dx = ((u64)d * PSCHED_TICKS_PER_SEC);
 458        dx += USEC_PER_SEC - 1;
 459        do_div(dx, USEC_PER_SEC);
 460        return dx;
 461}
 462
 463/* convert sm (bytes/psched us) into m (bps) */
 464static u32
 465sm2m(u64 sm)
 466{
 467        u64 m;
 468
 469        m = (sm * PSCHED_TICKS_PER_SEC) >> SM_SHIFT;
 470        return (u32)m;
 471}
 472
 473/* convert dx (psched us) into d (us) */
 474static u32
 475dx2d(u64 dx)
 476{
 477        u64 d;
 478
 479        d = dx * USEC_PER_SEC;
 480        do_div(d, PSCHED_TICKS_PER_SEC);
 481        return (u32)d;
 482}
 483
 484static void
 485sc2isc(struct tc_service_curve *sc, struct internal_sc *isc)
 486{
 487        isc->sm1  = m2sm(sc->m1);
 488        isc->ism1 = m2ism(sc->m1);
 489        isc->dx   = d2dx(sc->d);
 490        isc->dy   = seg_x2y(isc->dx, isc->sm1);
 491        isc->sm2  = m2sm(sc->m2);
 492        isc->ism2 = m2ism(sc->m2);
 493}
 494
 495/*
 496 * initialize the runtime service curve with the given internal
 497 * service curve starting at (x, y).
 498 */
 499static void
 500rtsc_init(struct runtime_sc *rtsc, struct internal_sc *isc, u64 x, u64 y)
 501{
 502        rtsc->x    = x;
 503        rtsc->y    = y;
 504        rtsc->sm1  = isc->sm1;
 505        rtsc->ism1 = isc->ism1;
 506        rtsc->dx   = isc->dx;
 507        rtsc->dy   = isc->dy;
 508        rtsc->sm2  = isc->sm2;
 509        rtsc->ism2 = isc->ism2;
 510}
 511
 512/*
 513 * calculate the y-projection of the runtime service curve by the
 514 * given x-projection value
 515 */
 516static u64
 517rtsc_y2x(struct runtime_sc *rtsc, u64 y)
 518{
 519        u64 x;
 520
 521        if (y < rtsc->y)
 522                x = rtsc->x;
 523        else if (y <= rtsc->y + rtsc->dy) {
 524                /* x belongs to the 1st segment */
 525                if (rtsc->dy == 0)
 526                        x = rtsc->x + rtsc->dx;
 527                else
 528                        x = rtsc->x + seg_y2x(y - rtsc->y, rtsc->ism1);
 529        } else {
 530                /* x belongs to the 2nd segment */
 531                x = rtsc->x + rtsc->dx
 532                    + seg_y2x(y - rtsc->y - rtsc->dy, rtsc->ism2);
 533        }
 534        return x;
 535}
 536
 537static u64
 538rtsc_x2y(struct runtime_sc *rtsc, u64 x)
 539{
 540        u64 y;
 541
 542        if (x <= rtsc->x)
 543                y = rtsc->y;
 544        else if (x <= rtsc->x + rtsc->dx)
 545                /* y belongs to the 1st segment */
 546                y = rtsc->y + seg_x2y(x - rtsc->x, rtsc->sm1);
 547        else
 548                /* y belongs to the 2nd segment */
 549                y = rtsc->y + rtsc->dy
 550                    + seg_x2y(x - rtsc->x - rtsc->dx, rtsc->sm2);
 551        return y;
 552}
 553
 554/*
 555 * update the runtime service curve by taking the minimum of the current
 556 * runtime service curve and the service curve starting at (x, y).
 557 */
 558static void
 559rtsc_min(struct runtime_sc *rtsc, struct internal_sc *isc, u64 x, u64 y)
 560{
 561        u64 y1, y2, dx, dy;
 562        u32 dsm;
 563
 564        if (isc->sm1 <= isc->sm2) {
 565                /* service curve is convex */
 566                y1 = rtsc_x2y(rtsc, x);
 567                if (y1 < y)
 568                        /* the current rtsc is smaller */
 569                        return;
 570                rtsc->x = x;
 571                rtsc->y = y;
 572                return;
 573        }
 574
 575        /*
 576         * service curve is concave
 577         * compute the two y values of the current rtsc
 578         *      y1: at x
 579         *      y2: at (x + dx)
 580         */
 581        y1 = rtsc_x2y(rtsc, x);
 582        if (y1 <= y) {
 583                /* rtsc is below isc, no change to rtsc */
 584                return;
 585        }
 586
 587        y2 = rtsc_x2y(rtsc, x + isc->dx);
 588        if (y2 >= y + isc->dy) {
 589                /* rtsc is above isc, replace rtsc by isc */
 590                rtsc->x = x;
 591                rtsc->y = y;
 592                rtsc->dx = isc->dx;
 593                rtsc->dy = isc->dy;
 594                return;
 595        }
 596
 597        /*
 598         * the two curves intersect
 599         * compute the offsets (dx, dy) using the reverse
 600         * function of seg_x2y()
 601         *      seg_x2y(dx, sm1) == seg_x2y(dx, sm2) + (y1 - y)
 602         */
 603        dx = (y1 - y) << SM_SHIFT;
 604        dsm = isc->sm1 - isc->sm2;
 605        do_div(dx, dsm);
 606        /*
 607         * check if (x, y1) belongs to the 1st segment of rtsc.
 608         * if so, add the offset.
 609         */
 610        if (rtsc->x + rtsc->dx > x)
 611                dx += rtsc->x + rtsc->dx - x;
 612        dy = seg_x2y(dx, isc->sm1);
 613
 614        rtsc->x = x;
 615        rtsc->y = y;
 616        rtsc->dx = dx;
 617        rtsc->dy = dy;
 618        return;
 619}
 620
 621static void
 622init_ed(struct hfsc_class *cl, unsigned int next_len)
 623{
 624        u64 cur_time = psched_get_time();
 625
 626        /* update the deadline curve */
 627        rtsc_min(&cl->cl_deadline, &cl->cl_rsc, cur_time, cl->cl_cumul);
 628
 629        /*
 630         * update the eligible curve.
 631         * for concave, it is equal to the deadline curve.
 632         * for convex, it is a linear curve with slope m2.
 633         */
 634        cl->cl_eligible = cl->cl_deadline;
 635        if (cl->cl_rsc.sm1 <= cl->cl_rsc.sm2) {
 636                cl->cl_eligible.dx = 0;
 637                cl->cl_eligible.dy = 0;
 638        }
 639
 640        /* compute e and d */
 641        cl->cl_e = rtsc_y2x(&cl->cl_eligible, cl->cl_cumul);
 642        cl->cl_d = rtsc_y2x(&cl->cl_deadline, cl->cl_cumul + next_len);
 643
 644        eltree_insert(cl);
 645}
 646
 647static void
 648update_ed(struct hfsc_class *cl, unsigned int next_len)
 649{
 650        cl->cl_e = rtsc_y2x(&cl->cl_eligible, cl->cl_cumul);
 651        cl->cl_d = rtsc_y2x(&cl->cl_deadline, cl->cl_cumul + next_len);
 652
 653        eltree_update(cl);
 654}
 655
 656static inline void
 657update_d(struct hfsc_class *cl, unsigned int next_len)
 658{
 659        cl->cl_d = rtsc_y2x(&cl->cl_deadline, cl->cl_cumul + next_len);
 660}
 661
 662static inline void
 663update_cfmin(struct hfsc_class *cl)
 664{
 665        struct rb_node *n = rb_first(&cl->cf_tree);
 666        struct hfsc_class *p;
 667
 668        if (n == NULL) {
 669                cl->cl_cfmin = 0;
 670                return;
 671        }
 672        p = rb_entry(n, struct hfsc_class, cf_node);
 673        cl->cl_cfmin = p->cl_f;
 674}
 675
 676static void
 677init_vf(struct hfsc_class *cl, unsigned int len)
 678{
 679        struct hfsc_class *max_cl;
 680        struct rb_node *n;
 681        u64 vt, f, cur_time;
 682        int go_active;
 683
 684        cur_time = 0;
 685        go_active = 1;
 686        for (; cl->cl_parent != NULL; cl = cl->cl_parent) {
 687                if (go_active && cl->cl_nactive++ == 0)
 688                        go_active = 1;
 689                else
 690                        go_active = 0;
 691
 692                if (go_active) {
 693                        n = rb_last(&cl->cl_parent->vt_tree);
 694                        if (n != NULL) {
 695                                max_cl = rb_entry(n, struct hfsc_class,vt_node);
 696                                /*
 697                                 * set vt to the average of the min and max
 698                                 * classes.  if the parent's period didn't
 699                                 * change, don't decrease vt of the class.
 700                                 */
 701                                vt = max_cl->cl_vt;
 702                                if (cl->cl_parent->cl_cvtmin != 0)
 703                                        vt = (cl->cl_parent->cl_cvtmin + vt)/2;
 704
 705                                if (cl->cl_parent->cl_vtperiod !=
 706                                    cl->cl_parentperiod || vt > cl->cl_vt)
 707                                        cl->cl_vt = vt;
 708                        } else {
 709                                /*
 710                                 * first child for a new parent backlog period.
 711                                 * add parent's cvtmax to cvtoff to make a new
 712                                 * vt (vtoff + vt) larger than the vt in the
 713                                 * last period for all children.
 714                                 */
 715                                vt = cl->cl_parent->cl_cvtmax;
 716                                cl->cl_parent->cl_cvtoff += vt;
 717                                cl->cl_parent->cl_cvtmax = 0;
 718                                cl->cl_parent->cl_cvtmin = 0;
 719                                cl->cl_vt = 0;
 720                        }
 721
 722                        cl->cl_vtoff = cl->cl_parent->cl_cvtoff -
 723                                                        cl->cl_pcvtoff;
 724
 725                        /* update the virtual curve */
 726                        vt = cl->cl_vt + cl->cl_vtoff;
 727                        rtsc_min(&cl->cl_virtual, &cl->cl_fsc, vt,
 728                                                      cl->cl_total);
 729                        if (cl->cl_virtual.x == vt) {
 730                                cl->cl_virtual.x -= cl->cl_vtoff;
 731                                cl->cl_vtoff = 0;
 732                        }
 733                        cl->cl_vtadj = 0;
 734
 735                        cl->cl_vtperiod++;  /* increment vt period */
 736                        cl->cl_parentperiod = cl->cl_parent->cl_vtperiod;
 737                        if (cl->cl_parent->cl_nactive == 0)
 738                                cl->cl_parentperiod++;
 739                        cl->cl_f = 0;
 740
 741                        vttree_insert(cl);
 742                        cftree_insert(cl);
 743
 744                        if (cl->cl_flags & HFSC_USC) {
 745                                /* class has upper limit curve */
 746                                if (cur_time == 0)
 747                                        cur_time = psched_get_time();
 748
 749                                /* update the ulimit curve */
 750                                rtsc_min(&cl->cl_ulimit, &cl->cl_usc, cur_time,
 751                                         cl->cl_total);
 752                                /* compute myf */
 753                                cl->cl_myf = rtsc_y2x(&cl->cl_ulimit,
 754                                                      cl->cl_total);
 755                                cl->cl_myfadj = 0;
 756                        }
 757                }
 758
 759                f = max(cl->cl_myf, cl->cl_cfmin);
 760                if (f != cl->cl_f) {
 761                        cl->cl_f = f;
 762                        cftree_update(cl);
 763                        update_cfmin(cl->cl_parent);
 764                }
 765        }
 766}
 767
 768static void
 769update_vf(struct hfsc_class *cl, unsigned int len, u64 cur_time)
 770{
 771        u64 f; /* , myf_bound, delta; */
 772        int go_passive = 0;
 773
 774        if (cl->qdisc->q.qlen == 0 && cl->cl_flags & HFSC_FSC)
 775                go_passive = 1;
 776
 777        for (; cl->cl_parent != NULL; cl = cl->cl_parent) {
 778                cl->cl_total += len;
 779
 780                if (!(cl->cl_flags & HFSC_FSC) || cl->cl_nactive == 0)
 781                        continue;
 782
 783                if (go_passive && --cl->cl_nactive == 0)
 784                        go_passive = 1;
 785                else
 786                        go_passive = 0;
 787
 788                if (go_passive) {
 789                        /* no more active child, going passive */
 790
 791                        /* update cvtmax of the parent class */
 792                        if (cl->cl_vt > cl->cl_parent->cl_cvtmax)
 793                                cl->cl_parent->cl_cvtmax = cl->cl_vt;
 794
 795                        /* remove this class from the vt tree */
 796                        vttree_remove(cl);
 797
 798                        cftree_remove(cl);
 799                        update_cfmin(cl->cl_parent);
 800
 801                        continue;
 802                }
 803
 804                /*
 805                 * update vt and f
 806                 */
 807                cl->cl_vt = rtsc_y2x(&cl->cl_virtual, cl->cl_total)
 808                            - cl->cl_vtoff + cl->cl_vtadj;
 809
 810                /*
 811                 * if vt of the class is smaller than cvtmin,
 812                 * the class was skipped in the past due to non-fit.
 813                 * if so, we need to adjust vtadj.
 814                 */
 815                if (cl->cl_vt < cl->cl_parent->cl_cvtmin) {
 816                        cl->cl_vtadj += cl->cl_parent->cl_cvtmin - cl->cl_vt;
 817                        cl->cl_vt = cl->cl_parent->cl_cvtmin;
 818                }
 819
 820                /* update the vt tree */
 821                vttree_update(cl);
 822
 823                if (cl->cl_flags & HFSC_USC) {
 824                        cl->cl_myf = cl->cl_myfadj + rtsc_y2x(&cl->cl_ulimit,
 825                                                              cl->cl_total);
 826#if 0
 827                        /*
 828                         * This code causes classes to stay way under their
 829                         * limit when multiple classes are used at gigabit
 830                         * speed. needs investigation. -kaber
 831                         */
 832                        /*
 833                         * if myf lags behind by more than one clock tick
 834                         * from the current time, adjust myfadj to prevent
 835                         * a rate-limited class from going greedy.
 836                         * in a steady state under rate-limiting, myf
 837                         * fluctuates within one clock tick.
 838                         */
 839                        myf_bound = cur_time - PSCHED_JIFFIE2US(1);
 840                        if (cl->cl_myf < myf_bound) {
 841                                delta = cur_time - cl->cl_myf;
 842                                cl->cl_myfadj += delta;
 843                                cl->cl_myf += delta;
 844                        }
 845#endif
 846                }
 847
 848                f = max(cl->cl_myf, cl->cl_cfmin);
 849                if (f != cl->cl_f) {
 850                        cl->cl_f = f;
 851                        cftree_update(cl);
 852                        update_cfmin(cl->cl_parent);
 853                }
 854        }
 855}
 856
 857static void
 858set_active(struct hfsc_class *cl, unsigned int len)
 859{
 860        if (cl->cl_flags & HFSC_RSC)
 861                init_ed(cl, len);
 862        if (cl->cl_flags & HFSC_FSC)
 863                init_vf(cl, len);
 864
 865        list_add_tail(&cl->dlist, &cl->sched->droplist);
 866}
 867
 868static void
 869set_passive(struct hfsc_class *cl)
 870{
 871        if (cl->cl_flags & HFSC_RSC)
 872                eltree_remove(cl);
 873
 874        list_del(&cl->dlist);
 875
 876        /*
 877         * vttree is now handled in update_vf() so that update_vf(cl, 0, 0)
 878         * needs to be called explicitly to remove a class from vttree.
 879         */
 880}
 881
 882static unsigned int
 883qdisc_peek_len(struct Qdisc *sch)
 884{
 885        struct sk_buff *skb;
 886        unsigned int len;
 887
 888        skb = sch->ops->peek(sch);
 889        if (skb == NULL) {
 890                if (net_ratelimit())
 891                        printk("qdisc_peek_len: non work-conserving qdisc ?\n");
 892                return 0;
 893        }
 894        len = qdisc_pkt_len(skb);
 895
 896        return len;
 897}
 898
 899static void
 900hfsc_purge_queue(struct Qdisc *sch, struct hfsc_class *cl)
 901{
 902        unsigned int len = cl->qdisc->q.qlen;
 903
 904        qdisc_reset(cl->qdisc);
 905        qdisc_tree_decrease_qlen(cl->qdisc, len);
 906}
 907
 908static void
 909hfsc_adjust_levels(struct hfsc_class *cl)
 910{
 911        struct hfsc_class *p;
 912        unsigned int level;
 913
 914        do {
 915                level = 0;
 916                list_for_each_entry(p, &cl->children, siblings) {
 917                        if (p->level >= level)
 918                                level = p->level + 1;
 919                }
 920                cl->level = level;
 921        } while ((cl = cl->cl_parent) != NULL);
 922}
 923
 924static inline struct hfsc_class *
 925hfsc_find_class(u32 classid, struct Qdisc *sch)
 926{
 927        struct hfsc_sched *q = qdisc_priv(sch);
 928        struct Qdisc_class_common *clc;
 929
 930        clc = qdisc_class_find(&q->clhash, classid);
 931        if (clc == NULL)
 932                return NULL;
 933        return container_of(clc, struct hfsc_class, cl_common);
 934}
 935
 936static void
 937hfsc_change_rsc(struct hfsc_class *cl, struct tc_service_curve *rsc,
 938                u64 cur_time)
 939{
 940        sc2isc(rsc, &cl->cl_rsc);
 941        rtsc_init(&cl->cl_deadline, &cl->cl_rsc, cur_time, cl->cl_cumul);
 942        cl->cl_eligible = cl->cl_deadline;
 943        if (cl->cl_rsc.sm1 <= cl->cl_rsc.sm2) {
 944                cl->cl_eligible.dx = 0;
 945                cl->cl_eligible.dy = 0;
 946        }
 947        cl->cl_flags |= HFSC_RSC;
 948}
 949
 950static void
 951hfsc_change_fsc(struct hfsc_class *cl, struct tc_service_curve *fsc)
 952{
 953        sc2isc(fsc, &cl->cl_fsc);
 954        rtsc_init(&cl->cl_virtual, &cl->cl_fsc, cl->cl_vt, cl->cl_total);
 955        cl->cl_flags |= HFSC_FSC;
 956}
 957
 958static void
 959hfsc_change_usc(struct hfsc_class *cl, struct tc_service_curve *usc,
 960                u64 cur_time)
 961{
 962        sc2isc(usc, &cl->cl_usc);
 963        rtsc_init(&cl->cl_ulimit, &cl->cl_usc, cur_time, cl->cl_total);
 964        cl->cl_flags |= HFSC_USC;
 965}
 966
 967static const struct nla_policy hfsc_policy[TCA_HFSC_MAX + 1] = {
 968        [TCA_HFSC_RSC]  = { .len = sizeof(struct tc_service_curve) },
 969        [TCA_HFSC_FSC]  = { .len = sizeof(struct tc_service_curve) },
 970        [TCA_HFSC_USC]  = { .len = sizeof(struct tc_service_curve) },
 971};
 972
 973static int
 974hfsc_change_class(struct Qdisc *sch, u32 classid, u32 parentid,
 975                  struct nlattr **tca, unsigned long *arg)
 976{
 977        struct hfsc_sched *q = qdisc_priv(sch);
 978        struct hfsc_class *cl = (struct hfsc_class *)*arg;
 979        struct hfsc_class *parent = NULL;
 980        struct nlattr *opt = tca[TCA_OPTIONS];
 981        struct nlattr *tb[TCA_HFSC_MAX + 1];
 982        struct tc_service_curve *rsc = NULL, *fsc = NULL, *usc = NULL;
 983        u64 cur_time;
 984        int err;
 985
 986        if (opt == NULL)
 987                return -EINVAL;
 988
 989        err = nla_parse_nested(tb, TCA_HFSC_MAX, opt, hfsc_policy);
 990        if (err < 0)
 991                return err;
 992
 993        if (tb[TCA_HFSC_RSC]) {
 994                rsc = nla_data(tb[TCA_HFSC_RSC]);
 995                if (rsc->m1 == 0 && rsc->m2 == 0)
 996                        rsc = NULL;
 997        }
 998
 999        if (tb[TCA_HFSC_FSC]) {
1000                fsc = nla_data(tb[TCA_HFSC_FSC]);
1001                if (fsc->m1 == 0 && fsc->m2 == 0)
1002                        fsc = NULL;
1003        }
1004
1005        if (tb[TCA_HFSC_USC]) {
1006                usc = nla_data(tb[TCA_HFSC_USC]);
1007                if (usc->m1 == 0 && usc->m2 == 0)
1008                        usc = NULL;
1009        }
1010
1011        if (cl != NULL) {
1012                if (parentid) {
1013                        if (cl->cl_parent &&
1014                            cl->cl_parent->cl_common.classid != parentid)
1015                                return -EINVAL;
1016                        if (cl->cl_parent == NULL && parentid != TC_H_ROOT)
1017                                return -EINVAL;
1018                }
1019                cur_time = psched_get_time();
1020
1021                if (tca[TCA_RATE]) {
1022                        err = gen_replace_estimator(&cl->bstats, &cl->rate_est,
1023                                              qdisc_root_sleeping_lock(sch),
1024                                              tca[TCA_RATE]);
1025                        if (err)
1026                                return err;
1027                }
1028
1029                sch_tree_lock(sch);
1030                if (rsc != NULL)
1031                        hfsc_change_rsc(cl, rsc, cur_time);
1032                if (fsc != NULL)
1033                        hfsc_change_fsc(cl, fsc);
1034                if (usc != NULL)
1035                        hfsc_change_usc(cl, usc, cur_time);
1036
1037                if (cl->qdisc->q.qlen != 0) {
1038                        if (cl->cl_flags & HFSC_RSC)
1039                                update_ed(cl, qdisc_peek_len(cl->qdisc));
1040                        if (cl->cl_flags & HFSC_FSC)
1041                                update_vf(cl, 0, cur_time);
1042                }
1043                sch_tree_unlock(sch);
1044
1045                return 0;
1046        }
1047
1048        if (parentid == TC_H_ROOT)
1049                return -EEXIST;
1050
1051        parent = &q->root;
1052        if (parentid) {
1053                parent = hfsc_find_class(parentid, sch);
1054                if (parent == NULL)
1055                        return -ENOENT;
1056        }
1057
1058        if (classid == 0 || TC_H_MAJ(classid ^ sch->handle) != 0)
1059                return -EINVAL;
1060        if (hfsc_find_class(classid, sch))
1061                return -EEXIST;
1062
1063        if (rsc == NULL && fsc == NULL)
1064                return -EINVAL;
1065
1066        cl = kzalloc(sizeof(struct hfsc_class), GFP_KERNEL);
1067        if (cl == NULL)
1068                return -ENOBUFS;
1069
1070        if (tca[TCA_RATE]) {
1071                err = gen_new_estimator(&cl->bstats, &cl->rate_est,
1072                                        qdisc_root_sleeping_lock(sch),
1073                                        tca[TCA_RATE]);
1074                if (err) {
1075                        kfree(cl);
1076                        return err;
1077                }
1078        }
1079
1080        if (rsc != NULL)
1081                hfsc_change_rsc(cl, rsc, 0);
1082        if (fsc != NULL)
1083                hfsc_change_fsc(cl, fsc);
1084        if (usc != NULL)
1085                hfsc_change_usc(cl, usc, 0);
1086
1087        cl->cl_common.classid = classid;
1088        cl->refcnt    = 1;
1089        cl->sched     = q;
1090        cl->cl_parent = parent;
1091        cl->qdisc = qdisc_create_dflt(qdisc_dev(sch), sch->dev_queue,
1092                                      &pfifo_qdisc_ops, classid);
1093        if (cl->qdisc == NULL)
1094                cl->qdisc = &noop_qdisc;
1095        INIT_LIST_HEAD(&cl->children);
1096        cl->vt_tree = RB_ROOT;
1097        cl->cf_tree = RB_ROOT;
1098
1099        sch_tree_lock(sch);
1100        qdisc_class_hash_insert(&q->clhash, &cl->cl_common);
1101        list_add_tail(&cl->siblings, &parent->children);
1102        if (parent->level == 0)
1103                hfsc_purge_queue(sch, parent);
1104        hfsc_adjust_levels(parent);
1105        cl->cl_pcvtoff = parent->cl_cvtoff;
1106        sch_tree_unlock(sch);
1107
1108        qdisc_class_hash_grow(sch, &q->clhash);
1109
1110        *arg = (unsigned long)cl;
1111        return 0;
1112}
1113
1114static void
1115hfsc_destroy_class(struct Qdisc *sch, struct hfsc_class *cl)
1116{
1117        struct hfsc_sched *q = qdisc_priv(sch);
1118
1119        tcf_destroy_chain(&cl->filter_list);
1120        qdisc_destroy(cl->qdisc);
1121        gen_kill_estimator(&cl->bstats, &cl->rate_est);
1122        if (cl != &q->root)
1123                kfree(cl);
1124}
1125
1126static int
1127hfsc_delete_class(struct Qdisc *sch, unsigned long arg)
1128{
1129        struct hfsc_sched *q = qdisc_priv(sch);
1130        struct hfsc_class *cl = (struct hfsc_class *)arg;
1131
1132        if (cl->level > 0 || cl->filter_cnt > 0 || cl == &q->root)
1133                return -EBUSY;
1134
1135        sch_tree_lock(sch);
1136
1137        list_del(&cl->siblings);
1138        hfsc_adjust_levels(cl->cl_parent);
1139
1140        hfsc_purge_queue(sch, cl);
1141        qdisc_class_hash_remove(&q->clhash, &cl->cl_common);
1142
1143        if (--cl->refcnt == 0)
1144                hfsc_destroy_class(sch, cl);
1145
1146        sch_tree_unlock(sch);
1147        return 0;
1148}
1149
1150static struct hfsc_class *
1151hfsc_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr)
1152{
1153        struct hfsc_sched *q = qdisc_priv(sch);
1154        struct hfsc_class *cl;
1155        struct tcf_result res;
1156        struct tcf_proto *tcf;
1157        int result;
1158
1159        if (TC_H_MAJ(skb->priority ^ sch->handle) == 0 &&
1160            (cl = hfsc_find_class(skb->priority, sch)) != NULL)
1161                if (cl->level == 0)
1162                        return cl;
1163
1164        *qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
1165        tcf = q->root.filter_list;
1166        while (tcf && (result = tc_classify(skb, tcf, &res)) >= 0) {
1167#ifdef CONFIG_NET_CLS_ACT
1168                switch (result) {
1169                case TC_ACT_QUEUED:
1170                case TC_ACT_STOLEN:
1171                        *qerr = NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
1172                case TC_ACT_SHOT:
1173                        return NULL;
1174                }
1175#endif
1176                if ((cl = (struct hfsc_class *)res.class) == NULL) {
1177                        if ((cl = hfsc_find_class(res.classid, sch)) == NULL)
1178                                break; /* filter selected invalid classid */
1179                }
1180
1181                if (cl->level == 0)
1182                        return cl; /* hit leaf class */
1183
1184                /* apply inner filter chain */
1185                tcf = cl->filter_list;
1186        }
1187
1188        /* classification failed, try default class */
1189        cl = hfsc_find_class(TC_H_MAKE(TC_H_MAJ(sch->handle), q->defcls), sch);
1190        if (cl == NULL || cl->level > 0)
1191                return NULL;
1192
1193        return cl;
1194}
1195
1196static int
1197hfsc_graft_class(struct Qdisc *sch, unsigned long arg, struct Qdisc *new,
1198                 struct Qdisc **old)
1199{
1200        struct hfsc_class *cl = (struct hfsc_class *)arg;
1201
1202        if (cl == NULL)
1203                return -ENOENT;
1204        if (cl->level > 0)
1205                return -EINVAL;
1206        if (new == NULL) {
1207                new = qdisc_create_dflt(qdisc_dev(sch), sch->dev_queue,
1208                                        &pfifo_qdisc_ops,
1209                                        cl->cl_common.classid);
1210                if (new == NULL)
1211                        new = &noop_qdisc;
1212        }
1213
1214        sch_tree_lock(sch);
1215        hfsc_purge_queue(sch, cl);
1216        *old = cl->qdisc;
1217        cl->qdisc = new;
1218        sch_tree_unlock(sch);
1219        return 0;
1220}
1221
1222static struct Qdisc *
1223hfsc_class_leaf(struct Qdisc *sch, unsigned long arg)
1224{
1225        struct hfsc_class *cl = (struct hfsc_class *)arg;
1226
1227        if (cl != NULL && cl->level == 0)
1228                return cl->qdisc;
1229
1230        return NULL;
1231}
1232
1233static void
1234hfsc_qlen_notify(struct Qdisc *sch, unsigned long arg)
1235{
1236        struct hfsc_class *cl = (struct hfsc_class *)arg;
1237
1238        if (cl->qdisc->q.qlen == 0) {
1239                update_vf(cl, 0, 0);
1240                set_passive(cl);
1241        }
1242}
1243
1244static unsigned long
1245hfsc_get_class(struct Qdisc *sch, u32 classid)
1246{
1247        struct hfsc_class *cl = hfsc_find_class(classid, sch);
1248
1249        if (cl != NULL)
1250                cl->refcnt++;
1251
1252        return (unsigned long)cl;
1253}
1254
1255static void
1256hfsc_put_class(struct Qdisc *sch, unsigned long arg)
1257{
1258        struct hfsc_class *cl = (struct hfsc_class *)arg;
1259
1260        if (--cl->refcnt == 0)
1261                hfsc_destroy_class(sch, cl);
1262}
1263
1264static unsigned long
1265hfsc_bind_tcf(struct Qdisc *sch, unsigned long parent, u32 classid)
1266{
1267        struct hfsc_class *p = (struct hfsc_class *)parent;
1268        struct hfsc_class *cl = hfsc_find_class(classid, sch);
1269
1270        if (cl != NULL) {
1271                if (p != NULL && p->level <= cl->level)
1272                        return 0;
1273                cl->filter_cnt++;
1274        }
1275
1276        return (unsigned long)cl;
1277}
1278
1279static void
1280hfsc_unbind_tcf(struct Qdisc *sch, unsigned long arg)
1281{
1282        struct hfsc_class *cl = (struct hfsc_class *)arg;
1283
1284        cl->filter_cnt--;
1285}
1286
1287static struct tcf_proto **
1288hfsc_tcf_chain(struct Qdisc *sch, unsigned long arg)
1289{
1290        struct hfsc_sched *q = qdisc_priv(sch);
1291        struct hfsc_class *cl = (struct hfsc_class *)arg;
1292
1293        if (cl == NULL)
1294                cl = &q->root;
1295
1296        return &cl->filter_list;
1297}
1298
1299static int
1300hfsc_dump_sc(struct sk_buff *skb, int attr, struct internal_sc *sc)
1301{
1302        struct tc_service_curve tsc;
1303
1304        tsc.m1 = sm2m(sc->sm1);
1305        tsc.d  = dx2d(sc->dx);
1306        tsc.m2 = sm2m(sc->sm2);
1307        NLA_PUT(skb, attr, sizeof(tsc), &tsc);
1308
1309        return skb->len;
1310
1311 nla_put_failure:
1312        return -1;
1313}
1314
1315static inline int
1316hfsc_dump_curves(struct sk_buff *skb, struct hfsc_class *cl)
1317{
1318        if ((cl->cl_flags & HFSC_RSC) &&
1319            (hfsc_dump_sc(skb, TCA_HFSC_RSC, &cl->cl_rsc) < 0))
1320                goto nla_put_failure;
1321
1322        if ((cl->cl_flags & HFSC_FSC) &&
1323            (hfsc_dump_sc(skb, TCA_HFSC_FSC, &cl->cl_fsc) < 0))
1324                goto nla_put_failure;
1325
1326        if ((cl->cl_flags & HFSC_USC) &&
1327            (hfsc_dump_sc(skb, TCA_HFSC_USC, &cl->cl_usc) < 0))
1328                goto nla_put_failure;
1329
1330        return skb->len;
1331
1332 nla_put_failure:
1333        return -1;
1334}
1335
1336static int
1337hfsc_dump_class(struct Qdisc *sch, unsigned long arg, struct sk_buff *skb,
1338                struct tcmsg *tcm)
1339{
1340        struct hfsc_class *cl = (struct hfsc_class *)arg;
1341        struct nlattr *nest;
1342
1343        tcm->tcm_parent = cl->cl_parent ? cl->cl_parent->cl_common.classid :
1344                                          TC_H_ROOT;
1345        tcm->tcm_handle = cl->cl_common.classid;
1346        if (cl->level == 0)
1347                tcm->tcm_info = cl->qdisc->handle;
1348
1349        nest = nla_nest_start(skb, TCA_OPTIONS);
1350        if (nest == NULL)
1351                goto nla_put_failure;
1352        if (hfsc_dump_curves(skb, cl) < 0)
1353                goto nla_put_failure;
1354        nla_nest_end(skb, nest);
1355        return skb->len;
1356
1357 nla_put_failure:
1358        nla_nest_cancel(skb, nest);
1359        return -EMSGSIZE;
1360}
1361
1362static int
1363hfsc_dump_class_stats(struct Qdisc *sch, unsigned long arg,
1364        struct gnet_dump *d)
1365{
1366        struct hfsc_class *cl = (struct hfsc_class *)arg;
1367        struct tc_hfsc_stats xstats;
1368
1369        cl->qstats.qlen = cl->qdisc->q.qlen;
1370        xstats.level   = cl->level;
1371        xstats.period  = cl->cl_vtperiod;
1372        xstats.work    = cl->cl_total;
1373        xstats.rtwork  = cl->cl_cumul;
1374
1375        if (gnet_stats_copy_basic(d, &cl->bstats) < 0 ||
1376            gnet_stats_copy_rate_est(d, &cl->rate_est) < 0 ||
1377            gnet_stats_copy_queue(d, &cl->qstats) < 0)
1378                return -1;
1379
1380        return gnet_stats_copy_app(d, &xstats, sizeof(xstats));
1381}
1382
1383
1384
1385static void
1386hfsc_walk(struct Qdisc *sch, struct qdisc_walker *arg)
1387{
1388        struct hfsc_sched *q = qdisc_priv(sch);
1389        struct hlist_node *n;
1390        struct hfsc_class *cl;
1391        unsigned int i;
1392
1393        if (arg->stop)
1394                return;
1395
1396        for (i = 0; i < q->clhash.hashsize; i++) {
1397                hlist_for_each_entry(cl, n, &q->clhash.hash[i],
1398                                     cl_common.hnode) {
1399                        if (arg->count < arg->skip) {
1400                                arg->count++;
1401                                continue;
1402                        }
1403                        if (arg->fn(sch, (unsigned long)cl, arg) < 0) {
1404                                arg->stop = 1;
1405                                return;
1406                        }
1407                        arg->count++;
1408                }
1409        }
1410}
1411
1412static void
1413hfsc_schedule_watchdog(struct Qdisc *sch)
1414{
1415        struct hfsc_sched *q = qdisc_priv(sch);
1416        struct hfsc_class *cl;
1417        u64 next_time = 0;
1418
1419        if ((cl = eltree_get_minel(q)) != NULL)
1420                next_time = cl->cl_e;
1421        if (q->root.cl_cfmin != 0) {
1422                if (next_time == 0 || next_time > q->root.cl_cfmin)
1423                        next_time = q->root.cl_cfmin;
1424        }
1425        WARN_ON(next_time == 0);
1426        qdisc_watchdog_schedule(&q->watchdog, next_time);
1427}
1428
1429static int
1430hfsc_init_qdisc(struct Qdisc *sch, struct nlattr *opt)
1431{
1432        struct hfsc_sched *q = qdisc_priv(sch);
1433        struct tc_hfsc_qopt *qopt;
1434        int err;
1435
1436        if (opt == NULL || nla_len(opt) < sizeof(*qopt))
1437                return -EINVAL;
1438        qopt = nla_data(opt);
1439
1440        q->defcls = qopt->defcls;
1441        err = qdisc_class_hash_init(&q->clhash);
1442        if (err < 0)
1443                return err;
1444        q->eligible = RB_ROOT;
1445        INIT_LIST_HEAD(&q->droplist);
1446
1447        q->root.cl_common.classid = sch->handle;
1448        q->root.refcnt  = 1;
1449        q->root.sched   = q;
1450        q->root.qdisc = qdisc_create_dflt(qdisc_dev(sch), sch->dev_queue,
1451                                          &pfifo_qdisc_ops,
1452                                          sch->handle);
1453        if (q->root.qdisc == NULL)
1454                q->root.qdisc = &noop_qdisc;
1455        INIT_LIST_HEAD(&q->root.children);
1456        q->root.vt_tree = RB_ROOT;
1457        q->root.cf_tree = RB_ROOT;
1458
1459        qdisc_class_hash_insert(&q->clhash, &q->root.cl_common);
1460        qdisc_class_hash_grow(sch, &q->clhash);
1461
1462        qdisc_watchdog_init(&q->watchdog, sch);
1463
1464        return 0;
1465}
1466
1467static int
1468hfsc_change_qdisc(struct Qdisc *sch, struct nlattr *opt)
1469{
1470        struct hfsc_sched *q = qdisc_priv(sch);
1471        struct tc_hfsc_qopt *qopt;
1472
1473        if (opt == NULL || nla_len(opt) < sizeof(*qopt))
1474                return -EINVAL;
1475        qopt = nla_data(opt);
1476
1477        sch_tree_lock(sch);
1478        q->defcls = qopt->defcls;
1479        sch_tree_unlock(sch);
1480
1481        return 0;
1482}
1483
1484static void
1485hfsc_reset_class(struct hfsc_class *cl)
1486{
1487        cl->cl_total        = 0;
1488        cl->cl_cumul        = 0;
1489        cl->cl_d            = 0;
1490        cl->cl_e            = 0;
1491        cl->cl_vt           = 0;
1492        cl->cl_vtadj        = 0;
1493        cl->cl_vtoff        = 0;
1494        cl->cl_cvtmin       = 0;
1495        cl->cl_cvtmax       = 0;
1496        cl->cl_cvtoff       = 0;
1497        cl->cl_pcvtoff      = 0;
1498        cl->cl_vtperiod     = 0;
1499        cl->cl_parentperiod = 0;
1500        cl->cl_f            = 0;
1501        cl->cl_myf          = 0;
1502        cl->cl_myfadj       = 0;
1503        cl->cl_cfmin        = 0;
1504        cl->cl_nactive      = 0;
1505
1506        cl->vt_tree = RB_ROOT;
1507        cl->cf_tree = RB_ROOT;
1508        qdisc_reset(cl->qdisc);
1509
1510        if (cl->cl_flags & HFSC_RSC)
1511                rtsc_init(&cl->cl_deadline, &cl->cl_rsc, 0, 0);
1512        if (cl->cl_flags & HFSC_FSC)
1513                rtsc_init(&cl->cl_virtual, &cl->cl_fsc, 0, 0);
1514        if (cl->cl_flags & HFSC_USC)
1515                rtsc_init(&cl->cl_ulimit, &cl->cl_usc, 0, 0);
1516}
1517
1518static void
1519hfsc_reset_qdisc(struct Qdisc *sch)
1520{
1521        struct hfsc_sched *q = qdisc_priv(sch);
1522        struct hfsc_class *cl;
1523        struct hlist_node *n;
1524        unsigned int i;
1525
1526        for (i = 0; i < q->clhash.hashsize; i++) {
1527                hlist_for_each_entry(cl, n, &q->clhash.hash[i], cl_common.hnode)
1528                        hfsc_reset_class(cl);
1529        }
1530        q->eligible = RB_ROOT;
1531        INIT_LIST_HEAD(&q->droplist);
1532        qdisc_watchdog_cancel(&q->watchdog);
1533        sch->q.qlen = 0;
1534}
1535
1536static void
1537hfsc_destroy_qdisc(struct Qdisc *sch)
1538{
1539        struct hfsc_sched *q = qdisc_priv(sch);
1540        struct hlist_node *n, *next;
1541        struct hfsc_class *cl;
1542        unsigned int i;
1543
1544        for (i = 0; i < q->clhash.hashsize; i++) {
1545                hlist_for_each_entry(cl, n, &q->clhash.hash[i], cl_common.hnode)
1546                        tcf_destroy_chain(&cl->filter_list);
1547        }
1548        for (i = 0; i < q->clhash.hashsize; i++) {
1549                hlist_for_each_entry_safe(cl, n, next, &q->clhash.hash[i],
1550                                          cl_common.hnode)
1551                        hfsc_destroy_class(sch, cl);
1552        }
1553        qdisc_class_hash_destroy(&q->clhash);
1554        qdisc_watchdog_cancel(&q->watchdog);
1555}
1556
1557static int
1558hfsc_dump_qdisc(struct Qdisc *sch, struct sk_buff *skb)
1559{
1560        struct hfsc_sched *q = qdisc_priv(sch);
1561        unsigned char *b = skb_tail_pointer(skb);
1562        struct tc_hfsc_qopt qopt;
1563
1564        qopt.defcls = q->defcls;
1565        NLA_PUT(skb, TCA_OPTIONS, sizeof(qopt), &qopt);
1566        return skb->len;
1567
1568 nla_put_failure:
1569        nlmsg_trim(skb, b);
1570        return -1;
1571}
1572
1573static int
1574hfsc_enqueue(struct sk_buff *skb, struct Qdisc *sch)
1575{
1576        struct hfsc_class *cl;
1577        int uninitialized_var(err);
1578
1579        cl = hfsc_classify(skb, sch, &err);
1580        if (cl == NULL) {
1581                if (err & __NET_XMIT_BYPASS)
1582                        sch->qstats.drops++;
1583                kfree_skb(skb);
1584                return err;
1585        }
1586
1587        err = qdisc_enqueue(skb, cl->qdisc);
1588        if (unlikely(err != NET_XMIT_SUCCESS)) {
1589                if (net_xmit_drop_count(err)) {
1590                        cl->qstats.drops++;
1591                        sch->qstats.drops++;
1592                }
1593                return err;
1594        }
1595
1596        if (cl->qdisc->q.qlen == 1)
1597                set_active(cl, qdisc_pkt_len(skb));
1598
1599        cl->bstats.packets++;
1600        cl->bstats.bytes += qdisc_pkt_len(skb);
1601        sch->bstats.packets++;
1602        sch->bstats.bytes += qdisc_pkt_len(skb);
1603        sch->q.qlen++;
1604
1605        return NET_XMIT_SUCCESS;
1606}
1607
1608static struct sk_buff *
1609hfsc_dequeue(struct Qdisc *sch)
1610{
1611        struct hfsc_sched *q = qdisc_priv(sch);
1612        struct hfsc_class *cl;
1613        struct sk_buff *skb;
1614        u64 cur_time;
1615        unsigned int next_len;
1616        int realtime = 0;
1617
1618        if (sch->q.qlen == 0)
1619                return NULL;
1620
1621        cur_time = psched_get_time();
1622
1623        /*
1624         * if there are eligible classes, use real-time criteria.
1625         * find the class with the minimum deadline among
1626         * the eligible classes.
1627         */
1628        if ((cl = eltree_get_mindl(q, cur_time)) != NULL) {
1629                realtime = 1;
1630        } else {
1631                /*
1632                 * use link-sharing criteria
1633                 * get the class with the minimum vt in the hierarchy
1634                 */
1635                cl = vttree_get_minvt(&q->root, cur_time);
1636                if (cl == NULL) {
1637                        sch->qstats.overlimits++;
1638                        hfsc_schedule_watchdog(sch);
1639                        return NULL;
1640                }
1641        }
1642
1643        skb = qdisc_dequeue_peeked(cl->qdisc);
1644        if (skb == NULL) {
1645                if (net_ratelimit())
1646                        printk("HFSC: Non-work-conserving qdisc ?\n");
1647                return NULL;
1648        }
1649
1650        update_vf(cl, qdisc_pkt_len(skb), cur_time);
1651        if (realtime)
1652                cl->cl_cumul += qdisc_pkt_len(skb);
1653
1654        if (cl->qdisc->q.qlen != 0) {
1655                if (cl->cl_flags & HFSC_RSC) {
1656                        /* update ed */
1657                        next_len = qdisc_peek_len(cl->qdisc);
1658                        if (realtime)
1659                                update_ed(cl, next_len);
1660                        else
1661                                update_d(cl, next_len);
1662                }
1663        } else {
1664                /* the class becomes passive */
1665                set_passive(cl);
1666        }
1667
1668        sch->flags &= ~TCQ_F_THROTTLED;
1669        sch->q.qlen--;
1670
1671        return skb;
1672}
1673
1674static unsigned int
1675hfsc_drop(struct Qdisc *sch)
1676{
1677        struct hfsc_sched *q = qdisc_priv(sch);
1678        struct hfsc_class *cl;
1679        unsigned int len;
1680
1681        list_for_each_entry(cl, &q->droplist, dlist) {
1682                if (cl->qdisc->ops->drop != NULL &&
1683                    (len = cl->qdisc->ops->drop(cl->qdisc)) > 0) {
1684                        if (cl->qdisc->q.qlen == 0) {
1685                                update_vf(cl, 0, 0);
1686                                set_passive(cl);
1687                        } else {
1688                                list_move_tail(&cl->dlist, &q->droplist);
1689                        }
1690                        cl->qstats.drops++;
1691                        sch->qstats.drops++;
1692                        sch->q.qlen--;
1693                        return len;
1694                }
1695        }
1696        return 0;
1697}
1698
1699static const struct Qdisc_class_ops hfsc_class_ops = {
1700        .change         = hfsc_change_class,
1701        .delete         = hfsc_delete_class,
1702        .graft          = hfsc_graft_class,
1703        .leaf           = hfsc_class_leaf,
1704        .qlen_notify    = hfsc_qlen_notify,
1705        .get            = hfsc_get_class,
1706        .put            = hfsc_put_class,
1707        .bind_tcf       = hfsc_bind_tcf,
1708        .unbind_tcf     = hfsc_unbind_tcf,
1709        .tcf_chain      = hfsc_tcf_chain,
1710        .dump           = hfsc_dump_class,
1711        .dump_stats     = hfsc_dump_class_stats,
1712        .walk           = hfsc_walk
1713};
1714
1715static struct Qdisc_ops hfsc_qdisc_ops __read_mostly = {
1716        .id             = "hfsc",
1717        .init           = hfsc_init_qdisc,
1718        .change         = hfsc_change_qdisc,
1719        .reset          = hfsc_reset_qdisc,
1720        .destroy        = hfsc_destroy_qdisc,
1721        .dump           = hfsc_dump_qdisc,
1722        .enqueue        = hfsc_enqueue,
1723        .dequeue        = hfsc_dequeue,
1724        .peek           = qdisc_peek_dequeued,
1725        .drop           = hfsc_drop,
1726        .cl_ops         = &hfsc_class_ops,
1727        .priv_size      = sizeof(struct hfsc_sched),
1728        .owner          = THIS_MODULE
1729};
1730
1731static int __init
1732hfsc_init(void)
1733{
1734        return register_qdisc(&hfsc_qdisc_ops);
1735}
1736
1737static void __exit
1738hfsc_cleanup(void)
1739{
1740        unregister_qdisc(&hfsc_qdisc_ops);
1741}
1742
1743MODULE_LICENSE("GPL");
1744module_init(hfsc_init);
1745module_exit(hfsc_cleanup);
1746