linux/net/sched/sch_hfsc.c
<<
>>
Prefs
   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 avoid 64-bit divide operations
  81 *   that are expensive on 32-bit architectures.
  82 */
  83
  84struct internal_sc {
  85        u64     sm1;    /* scaled slope of the 1st segment */
  86        u64     ism1;   /* scaled inverse-slope of the 1st segment */
  87        u64     dx;     /* the x-projection of the 1st segment */
  88        u64     dy;     /* the y-projection of the 1st segment */
  89        u64     sm2;    /* scaled slope of the 2nd segment */
  90        u64     ism2;   /* scaled inverse-slope of the 2nd segment */
  91};
  92
  93/* runtime service curve */
  94struct runtime_sc {
  95        u64     x;      /* current starting position on x-axis */
  96        u64     y;      /* current starting position on y-axis */
  97        u64     sm1;    /* scaled slope of the 1st segment */
  98        u64     ism1;   /* scaled inverse-slope of the 1st segment */
  99        u64     dx;     /* the x-projection of the 1st segment */
 100        u64     dy;     /* the y-projection of the 1st segment */
 101        u64     sm2;    /* scaled slope of the 2nd segment */
 102        u64     ism2;   /* scaled inverse-slope of the 2nd segment */
 103};
 104
 105enum hfsc_class_flags {
 106        HFSC_RSC = 0x1,
 107        HFSC_FSC = 0x2,
 108        HFSC_USC = 0x4
 109};
 110
 111struct hfsc_class {
 112        struct Qdisc_class_common cl_common;
 113
 114        struct gnet_stats_basic_packed bstats;
 115        struct gnet_stats_queue qstats;
 116        struct net_rate_estimator __rcu *rate_est;
 117        struct tcf_proto __rcu *filter_list; /* filter list */
 118        struct tcf_block *block;
 119        unsigned int    filter_cnt;     /* filter count */
 120        unsigned int    level;          /* class level in hierarchy */
 121
 122        struct hfsc_sched *sched;       /* scheduler data */
 123        struct hfsc_class *cl_parent;   /* parent class */
 124        struct list_head siblings;      /* sibling classes */
 125        struct list_head children;      /* child classes */
 126        struct Qdisc    *qdisc;         /* leaf qdisc */
 127
 128        struct rb_node el_node;         /* qdisc's eligible tree member */
 129        struct rb_root vt_tree;         /* active children sorted by cl_vt */
 130        struct rb_node vt_node;         /* parent's vt_tree member */
 131        struct rb_root cf_tree;         /* active children sorted by cl_f */
 132        struct rb_node cf_node;         /* parent's cf_heap member */
 133
 134        u64     cl_total;               /* total work in bytes */
 135        u64     cl_cumul;               /* cumulative work in bytes done by
 136                                           real-time criteria */
 137
 138        u64     cl_d;                   /* deadline*/
 139        u64     cl_e;                   /* eligible time */
 140        u64     cl_vt;                  /* virtual time */
 141        u64     cl_f;                   /* time when this class will fit for
 142                                           link-sharing, max(myf, cfmin) */
 143        u64     cl_myf;                 /* my fit-time (calculated from this
 144                                           class's own upperlimit curve) */
 145        u64     cl_cfmin;               /* earliest children's fit-time (used
 146                                           with cl_myf to obtain cl_f) */
 147        u64     cl_cvtmin;              /* minimal virtual time among the
 148                                           children fit for link-sharing
 149                                           (monotonic within a period) */
 150        u64     cl_vtadj;               /* intra-period cumulative vt
 151                                           adjustment */
 152        u64     cl_cvtoff;              /* largest virtual time seen among
 153                                           the children */
 154
 155        struct internal_sc cl_rsc;      /* internal real-time service curve */
 156        struct internal_sc cl_fsc;      /* internal fair service curve */
 157        struct internal_sc cl_usc;      /* internal upperlimit service curve */
 158        struct runtime_sc cl_deadline;  /* deadline curve */
 159        struct runtime_sc cl_eligible;  /* eligible curve */
 160        struct runtime_sc cl_virtual;   /* virtual curve */
 161        struct runtime_sc cl_ulimit;    /* upperlimit curve */
 162
 163        u8              cl_flags;       /* which curves are valid */
 164        u32             cl_vtperiod;    /* vt period sequence number */
 165        u32             cl_parentperiod;/* parent's vt period sequence number*/
 166        u32             cl_nactive;     /* number of active children */
 167};
 168
 169struct hfsc_sched {
 170        u16     defcls;                         /* default class id */
 171        struct hfsc_class root;                 /* root class */
 172        struct Qdisc_class_hash clhash;         /* class hash */
 173        struct rb_root eligible;                /* eligible tree */
 174        struct qdisc_watchdog watchdog;         /* watchdog timer */
 175};
 176
 177#define HT_INFINITY     0xffffffffffffffffULL   /* infinite time value */
 178
 179
 180/*
 181 * eligible tree holds backlogged classes being sorted by their eligible times.
 182 * there is one eligible tree per hfsc instance.
 183 */
 184
 185static void
 186eltree_insert(struct hfsc_class *cl)
 187{
 188        struct rb_node **p = &cl->sched->eligible.rb_node;
 189        struct rb_node *parent = NULL;
 190        struct hfsc_class *cl1;
 191
 192        while (*p != NULL) {
 193                parent = *p;
 194                cl1 = rb_entry(parent, struct hfsc_class, el_node);
 195                if (cl->cl_e >= cl1->cl_e)
 196                        p = &parent->rb_right;
 197                else
 198                        p = &parent->rb_left;
 199        }
 200        rb_link_node(&cl->el_node, parent, p);
 201        rb_insert_color(&cl->el_node, &cl->sched->eligible);
 202}
 203
 204static inline void
 205eltree_remove(struct hfsc_class *cl)
 206{
 207        rb_erase(&cl->el_node, &cl->sched->eligible);
 208}
 209
 210static inline void
 211eltree_update(struct hfsc_class *cl)
 212{
 213        eltree_remove(cl);
 214        eltree_insert(cl);
 215}
 216
 217/* find the class with the minimum deadline among the eligible classes */
 218static inline struct hfsc_class *
 219eltree_get_mindl(struct hfsc_sched *q, u64 cur_time)
 220{
 221        struct hfsc_class *p, *cl = NULL;
 222        struct rb_node *n;
 223
 224        for (n = rb_first(&q->eligible); n != NULL; n = rb_next(n)) {
 225                p = rb_entry(n, struct hfsc_class, el_node);
 226                if (p->cl_e > cur_time)
 227                        break;
 228                if (cl == NULL || p->cl_d < cl->cl_d)
 229                        cl = p;
 230        }
 231        return cl;
 232}
 233
 234/* find the class with minimum eligible time among the eligible classes */
 235static inline struct hfsc_class *
 236eltree_get_minel(struct hfsc_sched *q)
 237{
 238        struct rb_node *n;
 239
 240        n = rb_first(&q->eligible);
 241        if (n == NULL)
 242                return NULL;
 243        return rb_entry(n, struct hfsc_class, el_node);
 244}
 245
 246/*
 247 * vttree holds holds backlogged child classes being sorted by their virtual
 248 * time. each intermediate class has one vttree.
 249 */
 250static void
 251vttree_insert(struct hfsc_class *cl)
 252{
 253        struct rb_node **p = &cl->cl_parent->vt_tree.rb_node;
 254        struct rb_node *parent = NULL;
 255        struct hfsc_class *cl1;
 256
 257        while (*p != NULL) {
 258                parent = *p;
 259                cl1 = rb_entry(parent, struct hfsc_class, vt_node);
 260                if (cl->cl_vt >= cl1->cl_vt)
 261                        p = &parent->rb_right;
 262                else
 263                        p = &parent->rb_left;
 264        }
 265        rb_link_node(&cl->vt_node, parent, p);
 266        rb_insert_color(&cl->vt_node, &cl->cl_parent->vt_tree);
 267}
 268
 269static inline void
 270vttree_remove(struct hfsc_class *cl)
 271{
 272        rb_erase(&cl->vt_node, &cl->cl_parent->vt_tree);
 273}
 274
 275static inline void
 276vttree_update(struct hfsc_class *cl)
 277{
 278        vttree_remove(cl);
 279        vttree_insert(cl);
 280}
 281
 282static inline struct hfsc_class *
 283vttree_firstfit(struct hfsc_class *cl, u64 cur_time)
 284{
 285        struct hfsc_class *p;
 286        struct rb_node *n;
 287
 288        for (n = rb_first(&cl->vt_tree); n != NULL; n = rb_next(n)) {
 289                p = rb_entry(n, struct hfsc_class, vt_node);
 290                if (p->cl_f <= cur_time)
 291                        return p;
 292        }
 293        return NULL;
 294}
 295
 296/*
 297 * get the leaf class with the minimum vt in the hierarchy
 298 */
 299static struct hfsc_class *
 300vttree_get_minvt(struct hfsc_class *cl, u64 cur_time)
 301{
 302        /* if root-class's cfmin is bigger than cur_time nothing to do */
 303        if (cl->cl_cfmin > cur_time)
 304                return NULL;
 305
 306        while (cl->level > 0) {
 307                cl = vttree_firstfit(cl, cur_time);
 308                if (cl == NULL)
 309                        return NULL;
 310                /*
 311                 * update parent's cl_cvtmin.
 312                 */
 313                if (cl->cl_parent->cl_cvtmin < cl->cl_vt)
 314                        cl->cl_parent->cl_cvtmin = cl->cl_vt;
 315        }
 316        return cl;
 317}
 318
 319static void
 320cftree_insert(struct hfsc_class *cl)
 321{
 322        struct rb_node **p = &cl->cl_parent->cf_tree.rb_node;
 323        struct rb_node *parent = NULL;
 324        struct hfsc_class *cl1;
 325
 326        while (*p != NULL) {
 327                parent = *p;
 328                cl1 = rb_entry(parent, struct hfsc_class, cf_node);
 329                if (cl->cl_f >= cl1->cl_f)
 330                        p = &parent->rb_right;
 331                else
 332                        p = &parent->rb_left;
 333        }
 334        rb_link_node(&cl->cf_node, parent, p);
 335        rb_insert_color(&cl->cf_node, &cl->cl_parent->cf_tree);
 336}
 337
 338static inline void
 339cftree_remove(struct hfsc_class *cl)
 340{
 341        rb_erase(&cl->cf_node, &cl->cl_parent->cf_tree);
 342}
 343
 344static inline void
 345cftree_update(struct hfsc_class *cl)
 346{
 347        cftree_remove(cl);
 348        cftree_insert(cl);
 349}
 350
 351/*
 352 * service curve support functions
 353 *
 354 *  external service curve parameters
 355 *      m: bps
 356 *      d: us
 357 *  internal service curve parameters
 358 *      sm: (bytes/psched_us) << SM_SHIFT
 359 *      ism: (psched_us/byte) << ISM_SHIFT
 360 *      dx: psched_us
 361 *
 362 * The clock source resolution with ktime and PSCHED_SHIFT 10 is 1.024us.
 363 *
 364 * sm and ism are scaled in order to keep effective digits.
 365 * SM_SHIFT and ISM_SHIFT are selected to keep at least 4 effective
 366 * digits in decimal using the following table.
 367 *
 368 *  bits/sec      100Kbps     1Mbps     10Mbps     100Mbps    1Gbps
 369 *  ------------+-------------------------------------------------------
 370 *  bytes/1.024us 12.8e-3    128e-3     1280e-3    12800e-3   128000e-3
 371 *
 372 *  1.024us/byte  78.125     7.8125     0.78125    0.078125   0.0078125
 373 *
 374 * So, for PSCHED_SHIFT 10 we need: SM_SHIFT 20, ISM_SHIFT 18.
 375 */
 376#define SM_SHIFT        (30 - PSCHED_SHIFT)
 377#define ISM_SHIFT       (8 + PSCHED_SHIFT)
 378
 379#define SM_MASK         ((1ULL << SM_SHIFT) - 1)
 380#define ISM_MASK        ((1ULL << ISM_SHIFT) - 1)
 381
 382static inline u64
 383seg_x2y(u64 x, u64 sm)
 384{
 385        u64 y;
 386
 387        /*
 388         * compute
 389         *      y = x * sm >> SM_SHIFT
 390         * but divide it for the upper and lower bits to avoid overflow
 391         */
 392        y = (x >> SM_SHIFT) * sm + (((x & SM_MASK) * sm) >> SM_SHIFT);
 393        return y;
 394}
 395
 396static inline u64
 397seg_y2x(u64 y, u64 ism)
 398{
 399        u64 x;
 400
 401        if (y == 0)
 402                x = 0;
 403        else if (ism == HT_INFINITY)
 404                x = HT_INFINITY;
 405        else {
 406                x = (y >> ISM_SHIFT) * ism
 407                    + (((y & ISM_MASK) * ism) >> ISM_SHIFT);
 408        }
 409        return x;
 410}
 411
 412/* Convert m (bps) into sm (bytes/psched us) */
 413static u64
 414m2sm(u32 m)
 415{
 416        u64 sm;
 417
 418        sm = ((u64)m << SM_SHIFT);
 419        sm += PSCHED_TICKS_PER_SEC - 1;
 420        do_div(sm, PSCHED_TICKS_PER_SEC);
 421        return sm;
 422}
 423
 424/* convert m (bps) into ism (psched us/byte) */
 425static u64
 426m2ism(u32 m)
 427{
 428        u64 ism;
 429
 430        if (m == 0)
 431                ism = HT_INFINITY;
 432        else {
 433                ism = ((u64)PSCHED_TICKS_PER_SEC << ISM_SHIFT);
 434                ism += m - 1;
 435                do_div(ism, m);
 436        }
 437        return ism;
 438}
 439
 440/* convert d (us) into dx (psched us) */
 441static u64
 442d2dx(u32 d)
 443{
 444        u64 dx;
 445
 446        dx = ((u64)d * PSCHED_TICKS_PER_SEC);
 447        dx += USEC_PER_SEC - 1;
 448        do_div(dx, USEC_PER_SEC);
 449        return dx;
 450}
 451
 452/* convert sm (bytes/psched us) into m (bps) */
 453static u32
 454sm2m(u64 sm)
 455{
 456        u64 m;
 457
 458        m = (sm * PSCHED_TICKS_PER_SEC) >> SM_SHIFT;
 459        return (u32)m;
 460}
 461
 462/* convert dx (psched us) into d (us) */
 463static u32
 464dx2d(u64 dx)
 465{
 466        u64 d;
 467
 468        d = dx * USEC_PER_SEC;
 469        do_div(d, PSCHED_TICKS_PER_SEC);
 470        return (u32)d;
 471}
 472
 473static void
 474sc2isc(struct tc_service_curve *sc, struct internal_sc *isc)
 475{
 476        isc->sm1  = m2sm(sc->m1);
 477        isc->ism1 = m2ism(sc->m1);
 478        isc->dx   = d2dx(sc->d);
 479        isc->dy   = seg_x2y(isc->dx, isc->sm1);
 480        isc->sm2  = m2sm(sc->m2);
 481        isc->ism2 = m2ism(sc->m2);
 482}
 483
 484/*
 485 * initialize the runtime service curve with the given internal
 486 * service curve starting at (x, y).
 487 */
 488static void
 489rtsc_init(struct runtime_sc *rtsc, struct internal_sc *isc, u64 x, u64 y)
 490{
 491        rtsc->x    = x;
 492        rtsc->y    = y;
 493        rtsc->sm1  = isc->sm1;
 494        rtsc->ism1 = isc->ism1;
 495        rtsc->dx   = isc->dx;
 496        rtsc->dy   = isc->dy;
 497        rtsc->sm2  = isc->sm2;
 498        rtsc->ism2 = isc->ism2;
 499}
 500
 501/*
 502 * calculate the y-projection of the runtime service curve by the
 503 * given x-projection value
 504 */
 505static u64
 506rtsc_y2x(struct runtime_sc *rtsc, u64 y)
 507{
 508        u64 x;
 509
 510        if (y < rtsc->y)
 511                x = rtsc->x;
 512        else if (y <= rtsc->y + rtsc->dy) {
 513                /* x belongs to the 1st segment */
 514                if (rtsc->dy == 0)
 515                        x = rtsc->x + rtsc->dx;
 516                else
 517                        x = rtsc->x + seg_y2x(y - rtsc->y, rtsc->ism1);
 518        } else {
 519                /* x belongs to the 2nd segment */
 520                x = rtsc->x + rtsc->dx
 521                    + seg_y2x(y - rtsc->y - rtsc->dy, rtsc->ism2);
 522        }
 523        return x;
 524}
 525
 526static u64
 527rtsc_x2y(struct runtime_sc *rtsc, u64 x)
 528{
 529        u64 y;
 530
 531        if (x <= rtsc->x)
 532                y = rtsc->y;
 533        else if (x <= rtsc->x + rtsc->dx)
 534                /* y belongs to the 1st segment */
 535                y = rtsc->y + seg_x2y(x - rtsc->x, rtsc->sm1);
 536        else
 537                /* y belongs to the 2nd segment */
 538                y = rtsc->y + rtsc->dy
 539                    + seg_x2y(x - rtsc->x - rtsc->dx, rtsc->sm2);
 540        return y;
 541}
 542
 543/*
 544 * update the runtime service curve by taking the minimum of the current
 545 * runtime service curve and the service curve starting at (x, y).
 546 */
 547static void
 548rtsc_min(struct runtime_sc *rtsc, struct internal_sc *isc, u64 x, u64 y)
 549{
 550        u64 y1, y2, dx, dy;
 551        u32 dsm;
 552
 553        if (isc->sm1 <= isc->sm2) {
 554                /* service curve is convex */
 555                y1 = rtsc_x2y(rtsc, x);
 556                if (y1 < y)
 557                        /* the current rtsc is smaller */
 558                        return;
 559                rtsc->x = x;
 560                rtsc->y = y;
 561                return;
 562        }
 563
 564        /*
 565         * service curve is concave
 566         * compute the two y values of the current rtsc
 567         *      y1: at x
 568         *      y2: at (x + dx)
 569         */
 570        y1 = rtsc_x2y(rtsc, x);
 571        if (y1 <= y) {
 572                /* rtsc is below isc, no change to rtsc */
 573                return;
 574        }
 575
 576        y2 = rtsc_x2y(rtsc, x + isc->dx);
 577        if (y2 >= y + isc->dy) {
 578                /* rtsc is above isc, replace rtsc by isc */
 579                rtsc->x = x;
 580                rtsc->y = y;
 581                rtsc->dx = isc->dx;
 582                rtsc->dy = isc->dy;
 583                return;
 584        }
 585
 586        /*
 587         * the two curves intersect
 588         * compute the offsets (dx, dy) using the reverse
 589         * function of seg_x2y()
 590         *      seg_x2y(dx, sm1) == seg_x2y(dx, sm2) + (y1 - y)
 591         */
 592        dx = (y1 - y) << SM_SHIFT;
 593        dsm = isc->sm1 - isc->sm2;
 594        do_div(dx, dsm);
 595        /*
 596         * check if (x, y1) belongs to the 1st segment of rtsc.
 597         * if so, add the offset.
 598         */
 599        if (rtsc->x + rtsc->dx > x)
 600                dx += rtsc->x + rtsc->dx - x;
 601        dy = seg_x2y(dx, isc->sm1);
 602
 603        rtsc->x = x;
 604        rtsc->y = y;
 605        rtsc->dx = dx;
 606        rtsc->dy = dy;
 607}
 608
 609static void
 610init_ed(struct hfsc_class *cl, unsigned int next_len)
 611{
 612        u64 cur_time = psched_get_time();
 613
 614        /* update the deadline curve */
 615        rtsc_min(&cl->cl_deadline, &cl->cl_rsc, cur_time, cl->cl_cumul);
 616
 617        /*
 618         * update the eligible curve.
 619         * for concave, it is equal to the deadline curve.
 620         * for convex, it is a linear curve with slope m2.
 621         */
 622        cl->cl_eligible = cl->cl_deadline;
 623        if (cl->cl_rsc.sm1 <= cl->cl_rsc.sm2) {
 624                cl->cl_eligible.dx = 0;
 625                cl->cl_eligible.dy = 0;
 626        }
 627
 628        /* compute e and d */
 629        cl->cl_e = rtsc_y2x(&cl->cl_eligible, cl->cl_cumul);
 630        cl->cl_d = rtsc_y2x(&cl->cl_deadline, cl->cl_cumul + next_len);
 631
 632        eltree_insert(cl);
 633}
 634
 635static void
 636update_ed(struct hfsc_class *cl, unsigned int next_len)
 637{
 638        cl->cl_e = rtsc_y2x(&cl->cl_eligible, cl->cl_cumul);
 639        cl->cl_d = rtsc_y2x(&cl->cl_deadline, cl->cl_cumul + next_len);
 640
 641        eltree_update(cl);
 642}
 643
 644static inline void
 645update_d(struct hfsc_class *cl, unsigned int next_len)
 646{
 647        cl->cl_d = rtsc_y2x(&cl->cl_deadline, cl->cl_cumul + next_len);
 648}
 649
 650static inline void
 651update_cfmin(struct hfsc_class *cl)
 652{
 653        struct rb_node *n = rb_first(&cl->cf_tree);
 654        struct hfsc_class *p;
 655
 656        if (n == NULL) {
 657                cl->cl_cfmin = 0;
 658                return;
 659        }
 660        p = rb_entry(n, struct hfsc_class, cf_node);
 661        cl->cl_cfmin = p->cl_f;
 662}
 663
 664static void
 665init_vf(struct hfsc_class *cl, unsigned int len)
 666{
 667        struct hfsc_class *max_cl;
 668        struct rb_node *n;
 669        u64 vt, f, cur_time;
 670        int go_active;
 671
 672        cur_time = 0;
 673        go_active = 1;
 674        for (; cl->cl_parent != NULL; cl = cl->cl_parent) {
 675                if (go_active && cl->cl_nactive++ == 0)
 676                        go_active = 1;
 677                else
 678                        go_active = 0;
 679
 680                if (go_active) {
 681                        n = rb_last(&cl->cl_parent->vt_tree);
 682                        if (n != NULL) {
 683                                max_cl = rb_entry(n, struct hfsc_class, vt_node);
 684                                /*
 685                                 * set vt to the average of the min and max
 686                                 * classes.  if the parent's period didn't
 687                                 * change, don't decrease vt of the class.
 688                                 */
 689                                vt = max_cl->cl_vt;
 690                                if (cl->cl_parent->cl_cvtmin != 0)
 691                                        vt = (cl->cl_parent->cl_cvtmin + vt)/2;
 692
 693                                if (cl->cl_parent->cl_vtperiod !=
 694                                    cl->cl_parentperiod || vt > cl->cl_vt)
 695                                        cl->cl_vt = vt;
 696                        } else {
 697                                /*
 698                                 * first child for a new parent backlog period.
 699                                 * initialize cl_vt to the highest value seen
 700                                 * among the siblings. this is analogous to
 701                                 * what cur_time would provide in realtime case.
 702                                 */
 703                                cl->cl_vt = cl->cl_parent->cl_cvtoff;
 704                                cl->cl_parent->cl_cvtmin = 0;
 705                        }
 706
 707                        /* update the virtual curve */
 708                        rtsc_min(&cl->cl_virtual, &cl->cl_fsc, cl->cl_vt, cl->cl_total);
 709                        cl->cl_vtadj = 0;
 710
 711                        cl->cl_vtperiod++;  /* increment vt period */
 712                        cl->cl_parentperiod = cl->cl_parent->cl_vtperiod;
 713                        if (cl->cl_parent->cl_nactive == 0)
 714                                cl->cl_parentperiod++;
 715                        cl->cl_f = 0;
 716
 717                        vttree_insert(cl);
 718                        cftree_insert(cl);
 719
 720                        if (cl->cl_flags & HFSC_USC) {
 721                                /* class has upper limit curve */
 722                                if (cur_time == 0)
 723                                        cur_time = psched_get_time();
 724
 725                                /* update the ulimit curve */
 726                                rtsc_min(&cl->cl_ulimit, &cl->cl_usc, cur_time,
 727                                         cl->cl_total);
 728                                /* compute myf */
 729                                cl->cl_myf = rtsc_y2x(&cl->cl_ulimit,
 730                                                      cl->cl_total);
 731                        }
 732                }
 733
 734                f = max(cl->cl_myf, cl->cl_cfmin);
 735                if (f != cl->cl_f) {
 736                        cl->cl_f = f;
 737                        cftree_update(cl);
 738                }
 739                update_cfmin(cl->cl_parent);
 740        }
 741}
 742
 743static void
 744update_vf(struct hfsc_class *cl, unsigned int len, u64 cur_time)
 745{
 746        u64 f; /* , myf_bound, delta; */
 747        int go_passive = 0;
 748
 749        if (cl->qdisc->q.qlen == 0 && cl->cl_flags & HFSC_FSC)
 750                go_passive = 1;
 751
 752        for (; cl->cl_parent != NULL; cl = cl->cl_parent) {
 753                cl->cl_total += len;
 754
 755                if (!(cl->cl_flags & HFSC_FSC) || cl->cl_nactive == 0)
 756                        continue;
 757
 758                if (go_passive && --cl->cl_nactive == 0)
 759                        go_passive = 1;
 760                else
 761                        go_passive = 0;
 762
 763                /* update vt */
 764                cl->cl_vt = rtsc_y2x(&cl->cl_virtual, cl->cl_total) + cl->cl_vtadj;
 765
 766                /*
 767                 * if vt of the class is smaller than cvtmin,
 768                 * the class was skipped in the past due to non-fit.
 769                 * if so, we need to adjust vtadj.
 770                 */
 771                if (cl->cl_vt < cl->cl_parent->cl_cvtmin) {
 772                        cl->cl_vtadj += cl->cl_parent->cl_cvtmin - cl->cl_vt;
 773                        cl->cl_vt = cl->cl_parent->cl_cvtmin;
 774                }
 775
 776                if (go_passive) {
 777                        /* no more active child, going passive */
 778
 779                        /* update cvtoff of the parent class */
 780                        if (cl->cl_vt > cl->cl_parent->cl_cvtoff)
 781                                cl->cl_parent->cl_cvtoff = cl->cl_vt;
 782
 783                        /* remove this class from the vt tree */
 784                        vttree_remove(cl);
 785
 786                        cftree_remove(cl);
 787                        update_cfmin(cl->cl_parent);
 788
 789                        continue;
 790                }
 791
 792                /* update the vt tree */
 793                vttree_update(cl);
 794
 795                /* update f */
 796                if (cl->cl_flags & HFSC_USC) {
 797                        cl->cl_myf = rtsc_y2x(&cl->cl_ulimit, cl->cl_total);
 798#if 0
 799                        cl->cl_myf = cl->cl_myfadj + rtsc_y2x(&cl->cl_ulimit,
 800                                                              cl->cl_total);
 801                        /*
 802                         * This code causes classes to stay way under their
 803                         * limit when multiple classes are used at gigabit
 804                         * speed. needs investigation. -kaber
 805                         */
 806                        /*
 807                         * if myf lags behind by more than one clock tick
 808                         * from the current time, adjust myfadj to prevent
 809                         * a rate-limited class from going greedy.
 810                         * in a steady state under rate-limiting, myf
 811                         * fluctuates within one clock tick.
 812                         */
 813                        myf_bound = cur_time - PSCHED_JIFFIE2US(1);
 814                        if (cl->cl_myf < myf_bound) {
 815                                delta = cur_time - cl->cl_myf;
 816                                cl->cl_myfadj += delta;
 817                                cl->cl_myf += delta;
 818                        }
 819#endif
 820                }
 821
 822                f = max(cl->cl_myf, cl->cl_cfmin);
 823                if (f != cl->cl_f) {
 824                        cl->cl_f = f;
 825                        cftree_update(cl);
 826                        update_cfmin(cl->cl_parent);
 827                }
 828        }
 829}
 830
 831static unsigned int
 832qdisc_peek_len(struct Qdisc *sch)
 833{
 834        struct sk_buff *skb;
 835        unsigned int len;
 836
 837        skb = sch->ops->peek(sch);
 838        if (unlikely(skb == NULL)) {
 839                qdisc_warn_nonwc("qdisc_peek_len", sch);
 840                return 0;
 841        }
 842        len = qdisc_pkt_len(skb);
 843
 844        return len;
 845}
 846
 847static void
 848hfsc_adjust_levels(struct hfsc_class *cl)
 849{
 850        struct hfsc_class *p;
 851        unsigned int level;
 852
 853        do {
 854                level = 0;
 855                list_for_each_entry(p, &cl->children, siblings) {
 856                        if (p->level >= level)
 857                                level = p->level + 1;
 858                }
 859                cl->level = level;
 860        } while ((cl = cl->cl_parent) != NULL);
 861}
 862
 863static inline struct hfsc_class *
 864hfsc_find_class(u32 classid, struct Qdisc *sch)
 865{
 866        struct hfsc_sched *q = qdisc_priv(sch);
 867        struct Qdisc_class_common *clc;
 868
 869        clc = qdisc_class_find(&q->clhash, classid);
 870        if (clc == NULL)
 871                return NULL;
 872        return container_of(clc, struct hfsc_class, cl_common);
 873}
 874
 875static void
 876hfsc_change_rsc(struct hfsc_class *cl, struct tc_service_curve *rsc,
 877                u64 cur_time)
 878{
 879        sc2isc(rsc, &cl->cl_rsc);
 880        rtsc_init(&cl->cl_deadline, &cl->cl_rsc, cur_time, cl->cl_cumul);
 881        cl->cl_eligible = cl->cl_deadline;
 882        if (cl->cl_rsc.sm1 <= cl->cl_rsc.sm2) {
 883                cl->cl_eligible.dx = 0;
 884                cl->cl_eligible.dy = 0;
 885        }
 886        cl->cl_flags |= HFSC_RSC;
 887}
 888
 889static void
 890hfsc_change_fsc(struct hfsc_class *cl, struct tc_service_curve *fsc)
 891{
 892        sc2isc(fsc, &cl->cl_fsc);
 893        rtsc_init(&cl->cl_virtual, &cl->cl_fsc, cl->cl_vt, cl->cl_total);
 894        cl->cl_flags |= HFSC_FSC;
 895}
 896
 897static void
 898hfsc_change_usc(struct hfsc_class *cl, struct tc_service_curve *usc,
 899                u64 cur_time)
 900{
 901        sc2isc(usc, &cl->cl_usc);
 902        rtsc_init(&cl->cl_ulimit, &cl->cl_usc, cur_time, cl->cl_total);
 903        cl->cl_flags |= HFSC_USC;
 904}
 905
 906static const struct nla_policy hfsc_policy[TCA_HFSC_MAX + 1] = {
 907        [TCA_HFSC_RSC]  = { .len = sizeof(struct tc_service_curve) },
 908        [TCA_HFSC_FSC]  = { .len = sizeof(struct tc_service_curve) },
 909        [TCA_HFSC_USC]  = { .len = sizeof(struct tc_service_curve) },
 910};
 911
 912static int
 913hfsc_change_class(struct Qdisc *sch, u32 classid, u32 parentid,
 914                  struct nlattr **tca, unsigned long *arg,
 915                  struct netlink_ext_ack *extack)
 916{
 917        struct hfsc_sched *q = qdisc_priv(sch);
 918        struct hfsc_class *cl = (struct hfsc_class *)*arg;
 919        struct hfsc_class *parent = NULL;
 920        struct nlattr *opt = tca[TCA_OPTIONS];
 921        struct nlattr *tb[TCA_HFSC_MAX + 1];
 922        struct tc_service_curve *rsc = NULL, *fsc = NULL, *usc = NULL;
 923        u64 cur_time;
 924        int err;
 925
 926        if (opt == NULL)
 927                return -EINVAL;
 928
 929        err = nla_parse_nested_deprecated(tb, TCA_HFSC_MAX, opt, hfsc_policy,
 930                                          NULL);
 931        if (err < 0)
 932                return err;
 933
 934        if (tb[TCA_HFSC_RSC]) {
 935                rsc = nla_data(tb[TCA_HFSC_RSC]);
 936                if (rsc->m1 == 0 && rsc->m2 == 0)
 937                        rsc = NULL;
 938        }
 939
 940        if (tb[TCA_HFSC_FSC]) {
 941                fsc = nla_data(tb[TCA_HFSC_FSC]);
 942                if (fsc->m1 == 0 && fsc->m2 == 0)
 943                        fsc = NULL;
 944        }
 945
 946        if (tb[TCA_HFSC_USC]) {
 947                usc = nla_data(tb[TCA_HFSC_USC]);
 948                if (usc->m1 == 0 && usc->m2 == 0)
 949                        usc = NULL;
 950        }
 951
 952        if (cl != NULL) {
 953                int old_flags;
 954
 955                if (parentid) {
 956                        if (cl->cl_parent &&
 957                            cl->cl_parent->cl_common.classid != parentid)
 958                                return -EINVAL;
 959                        if (cl->cl_parent == NULL && parentid != TC_H_ROOT)
 960                                return -EINVAL;
 961                }
 962                cur_time = psched_get_time();
 963
 964                if (tca[TCA_RATE]) {
 965                        err = gen_replace_estimator(&cl->bstats, NULL,
 966                                                    &cl->rate_est,
 967                                                    NULL,
 968                                                    qdisc_root_sleeping_running(sch),
 969                                                    tca[TCA_RATE]);
 970                        if (err)
 971                                return err;
 972                }
 973
 974                sch_tree_lock(sch);
 975                old_flags = cl->cl_flags;
 976
 977                if (rsc != NULL)
 978                        hfsc_change_rsc(cl, rsc, cur_time);
 979                if (fsc != NULL)
 980                        hfsc_change_fsc(cl, fsc);
 981                if (usc != NULL)
 982                        hfsc_change_usc(cl, usc, cur_time);
 983
 984                if (cl->qdisc->q.qlen != 0) {
 985                        int len = qdisc_peek_len(cl->qdisc);
 986
 987                        if (cl->cl_flags & HFSC_RSC) {
 988                                if (old_flags & HFSC_RSC)
 989                                        update_ed(cl, len);
 990                                else
 991                                        init_ed(cl, len);
 992                        }
 993
 994                        if (cl->cl_flags & HFSC_FSC) {
 995                                if (old_flags & HFSC_FSC)
 996                                        update_vf(cl, 0, cur_time);
 997                                else
 998                                        init_vf(cl, len);
 999                        }
1000                }
1001                sch_tree_unlock(sch);
1002
1003                return 0;
1004        }
1005
1006        if (parentid == TC_H_ROOT)
1007                return -EEXIST;
1008
1009        parent = &q->root;
1010        if (parentid) {
1011                parent = hfsc_find_class(parentid, sch);
1012                if (parent == NULL)
1013                        return -ENOENT;
1014        }
1015
1016        if (classid == 0 || TC_H_MAJ(classid ^ sch->handle) != 0)
1017                return -EINVAL;
1018        if (hfsc_find_class(classid, sch))
1019                return -EEXIST;
1020
1021        if (rsc == NULL && fsc == NULL)
1022                return -EINVAL;
1023
1024        cl = kzalloc(sizeof(struct hfsc_class), GFP_KERNEL);
1025        if (cl == NULL)
1026                return -ENOBUFS;
1027
1028        err = tcf_block_get(&cl->block, &cl->filter_list, sch, extack);
1029        if (err) {
1030                kfree(cl);
1031                return err;
1032        }
1033
1034        if (tca[TCA_RATE]) {
1035                err = gen_new_estimator(&cl->bstats, NULL, &cl->rate_est,
1036                                        NULL,
1037                                        qdisc_root_sleeping_running(sch),
1038                                        tca[TCA_RATE]);
1039                if (err) {
1040                        tcf_block_put(cl->block);
1041                        kfree(cl);
1042                        return err;
1043                }
1044        }
1045
1046        if (rsc != NULL)
1047                hfsc_change_rsc(cl, rsc, 0);
1048        if (fsc != NULL)
1049                hfsc_change_fsc(cl, fsc);
1050        if (usc != NULL)
1051                hfsc_change_usc(cl, usc, 0);
1052
1053        cl->cl_common.classid = classid;
1054        cl->sched     = q;
1055        cl->cl_parent = parent;
1056        cl->qdisc = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops,
1057                                      classid, NULL);
1058        if (cl->qdisc == NULL)
1059                cl->qdisc = &noop_qdisc;
1060        else
1061                qdisc_hash_add(cl->qdisc, true);
1062        INIT_LIST_HEAD(&cl->children);
1063        cl->vt_tree = RB_ROOT;
1064        cl->cf_tree = RB_ROOT;
1065
1066        sch_tree_lock(sch);
1067        qdisc_class_hash_insert(&q->clhash, &cl->cl_common);
1068        list_add_tail(&cl->siblings, &parent->children);
1069        if (parent->level == 0)
1070                qdisc_purge_queue(parent->qdisc);
1071        hfsc_adjust_levels(parent);
1072        sch_tree_unlock(sch);
1073
1074        qdisc_class_hash_grow(sch, &q->clhash);
1075
1076        *arg = (unsigned long)cl;
1077        return 0;
1078}
1079
1080static void
1081hfsc_destroy_class(struct Qdisc *sch, struct hfsc_class *cl)
1082{
1083        struct hfsc_sched *q = qdisc_priv(sch);
1084
1085        tcf_block_put(cl->block);
1086        qdisc_put(cl->qdisc);
1087        gen_kill_estimator(&cl->rate_est);
1088        if (cl != &q->root)
1089                kfree(cl);
1090}
1091
1092static int
1093hfsc_delete_class(struct Qdisc *sch, unsigned long arg,
1094                  struct netlink_ext_ack *extack)
1095{
1096        struct hfsc_sched *q = qdisc_priv(sch);
1097        struct hfsc_class *cl = (struct hfsc_class *)arg;
1098
1099        if (cl->level > 0 || cl->filter_cnt > 0 || cl == &q->root)
1100                return -EBUSY;
1101
1102        sch_tree_lock(sch);
1103
1104        list_del(&cl->siblings);
1105        hfsc_adjust_levels(cl->cl_parent);
1106
1107        qdisc_purge_queue(cl->qdisc);
1108        qdisc_class_hash_remove(&q->clhash, &cl->cl_common);
1109
1110        sch_tree_unlock(sch);
1111
1112        hfsc_destroy_class(sch, cl);
1113        return 0;
1114}
1115
1116static struct hfsc_class *
1117hfsc_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr)
1118{
1119        struct hfsc_sched *q = qdisc_priv(sch);
1120        struct hfsc_class *head, *cl;
1121        struct tcf_result res;
1122        struct tcf_proto *tcf;
1123        int result;
1124
1125        if (TC_H_MAJ(skb->priority ^ sch->handle) == 0 &&
1126            (cl = hfsc_find_class(skb->priority, sch)) != NULL)
1127                if (cl->level == 0)
1128                        return cl;
1129
1130        *qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
1131        head = &q->root;
1132        tcf = rcu_dereference_bh(q->root.filter_list);
1133        while (tcf && (result = tcf_classify(skb, tcf, &res, false)) >= 0) {
1134#ifdef CONFIG_NET_CLS_ACT
1135                switch (result) {
1136                case TC_ACT_QUEUED:
1137                case TC_ACT_STOLEN:
1138                case TC_ACT_TRAP:
1139                        *qerr = NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
1140                        fallthrough;
1141                case TC_ACT_SHOT:
1142                        return NULL;
1143                }
1144#endif
1145                cl = (struct hfsc_class *)res.class;
1146                if (!cl) {
1147                        cl = hfsc_find_class(res.classid, sch);
1148                        if (!cl)
1149                                break; /* filter selected invalid classid */
1150                        if (cl->level >= head->level)
1151                                break; /* filter may only point downwards */
1152                }
1153
1154                if (cl->level == 0)
1155                        return cl; /* hit leaf class */
1156
1157                /* apply inner filter chain */
1158                tcf = rcu_dereference_bh(cl->filter_list);
1159                head = cl;
1160        }
1161
1162        /* classification failed, try default class */
1163        cl = hfsc_find_class(TC_H_MAKE(TC_H_MAJ(sch->handle), q->defcls), sch);
1164        if (cl == NULL || cl->level > 0)
1165                return NULL;
1166
1167        return cl;
1168}
1169
1170static int
1171hfsc_graft_class(struct Qdisc *sch, unsigned long arg, struct Qdisc *new,
1172                 struct Qdisc **old, struct netlink_ext_ack *extack)
1173{
1174        struct hfsc_class *cl = (struct hfsc_class *)arg;
1175
1176        if (cl->level > 0)
1177                return -EINVAL;
1178        if (new == NULL) {
1179                new = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops,
1180                                        cl->cl_common.classid, NULL);
1181                if (new == NULL)
1182                        new = &noop_qdisc;
1183        }
1184
1185        *old = qdisc_replace(sch, new, &cl->qdisc);
1186        return 0;
1187}
1188
1189static struct Qdisc *
1190hfsc_class_leaf(struct Qdisc *sch, unsigned long arg)
1191{
1192        struct hfsc_class *cl = (struct hfsc_class *)arg;
1193
1194        if (cl->level == 0)
1195                return cl->qdisc;
1196
1197        return NULL;
1198}
1199
1200static void
1201hfsc_qlen_notify(struct Qdisc *sch, unsigned long arg)
1202{
1203        struct hfsc_class *cl = (struct hfsc_class *)arg;
1204
1205        /* vttree is now handled in update_vf() so that update_vf(cl, 0, 0)
1206         * needs to be called explicitly to remove a class from vttree.
1207         */
1208        update_vf(cl, 0, 0);
1209        if (cl->cl_flags & HFSC_RSC)
1210                eltree_remove(cl);
1211}
1212
1213static unsigned long
1214hfsc_search_class(struct Qdisc *sch, u32 classid)
1215{
1216        return (unsigned long)hfsc_find_class(classid, sch);
1217}
1218
1219static unsigned long
1220hfsc_bind_tcf(struct Qdisc *sch, unsigned long parent, u32 classid)
1221{
1222        struct hfsc_class *p = (struct hfsc_class *)parent;
1223        struct hfsc_class *cl = hfsc_find_class(classid, sch);
1224
1225        if (cl != NULL) {
1226                if (p != NULL && p->level <= cl->level)
1227                        return 0;
1228                cl->filter_cnt++;
1229        }
1230
1231        return (unsigned long)cl;
1232}
1233
1234static void
1235hfsc_unbind_tcf(struct Qdisc *sch, unsigned long arg)
1236{
1237        struct hfsc_class *cl = (struct hfsc_class *)arg;
1238
1239        cl->filter_cnt--;
1240}
1241
1242static struct tcf_block *hfsc_tcf_block(struct Qdisc *sch, unsigned long arg,
1243                                        struct netlink_ext_ack *extack)
1244{
1245        struct hfsc_sched *q = qdisc_priv(sch);
1246        struct hfsc_class *cl = (struct hfsc_class *)arg;
1247
1248        if (cl == NULL)
1249                cl = &q->root;
1250
1251        return cl->block;
1252}
1253
1254static int
1255hfsc_dump_sc(struct sk_buff *skb, int attr, struct internal_sc *sc)
1256{
1257        struct tc_service_curve tsc;
1258
1259        tsc.m1 = sm2m(sc->sm1);
1260        tsc.d  = dx2d(sc->dx);
1261        tsc.m2 = sm2m(sc->sm2);
1262        if (nla_put(skb, attr, sizeof(tsc), &tsc))
1263                goto nla_put_failure;
1264
1265        return skb->len;
1266
1267 nla_put_failure:
1268        return -1;
1269}
1270
1271static int
1272hfsc_dump_curves(struct sk_buff *skb, struct hfsc_class *cl)
1273{
1274        if ((cl->cl_flags & HFSC_RSC) &&
1275            (hfsc_dump_sc(skb, TCA_HFSC_RSC, &cl->cl_rsc) < 0))
1276                goto nla_put_failure;
1277
1278        if ((cl->cl_flags & HFSC_FSC) &&
1279            (hfsc_dump_sc(skb, TCA_HFSC_FSC, &cl->cl_fsc) < 0))
1280                goto nla_put_failure;
1281
1282        if ((cl->cl_flags & HFSC_USC) &&
1283            (hfsc_dump_sc(skb, TCA_HFSC_USC, &cl->cl_usc) < 0))
1284                goto nla_put_failure;
1285
1286        return skb->len;
1287
1288 nla_put_failure:
1289        return -1;
1290}
1291
1292static int
1293hfsc_dump_class(struct Qdisc *sch, unsigned long arg, struct sk_buff *skb,
1294                struct tcmsg *tcm)
1295{
1296        struct hfsc_class *cl = (struct hfsc_class *)arg;
1297        struct nlattr *nest;
1298
1299        tcm->tcm_parent = cl->cl_parent ? cl->cl_parent->cl_common.classid :
1300                                          TC_H_ROOT;
1301        tcm->tcm_handle = cl->cl_common.classid;
1302        if (cl->level == 0)
1303                tcm->tcm_info = cl->qdisc->handle;
1304
1305        nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
1306        if (nest == NULL)
1307                goto nla_put_failure;
1308        if (hfsc_dump_curves(skb, cl) < 0)
1309                goto nla_put_failure;
1310        return nla_nest_end(skb, nest);
1311
1312 nla_put_failure:
1313        nla_nest_cancel(skb, nest);
1314        return -EMSGSIZE;
1315}
1316
1317static int
1318hfsc_dump_class_stats(struct Qdisc *sch, unsigned long arg,
1319        struct gnet_dump *d)
1320{
1321        struct hfsc_class *cl = (struct hfsc_class *)arg;
1322        struct tc_hfsc_stats xstats;
1323        __u32 qlen;
1324
1325        qdisc_qstats_qlen_backlog(cl->qdisc, &qlen, &cl->qstats.backlog);
1326        xstats.level   = cl->level;
1327        xstats.period  = cl->cl_vtperiod;
1328        xstats.work    = cl->cl_total;
1329        xstats.rtwork  = cl->cl_cumul;
1330
1331        if (gnet_stats_copy_basic(qdisc_root_sleeping_running(sch), d, NULL, &cl->bstats) < 0 ||
1332            gnet_stats_copy_rate_est(d, &cl->rate_est) < 0 ||
1333            gnet_stats_copy_queue(d, NULL, &cl->qstats, qlen) < 0)
1334                return -1;
1335
1336        return gnet_stats_copy_app(d, &xstats, sizeof(xstats));
1337}
1338
1339
1340
1341static void
1342hfsc_walk(struct Qdisc *sch, struct qdisc_walker *arg)
1343{
1344        struct hfsc_sched *q = qdisc_priv(sch);
1345        struct hfsc_class *cl;
1346        unsigned int i;
1347
1348        if (arg->stop)
1349                return;
1350
1351        for (i = 0; i < q->clhash.hashsize; i++) {
1352                hlist_for_each_entry(cl, &q->clhash.hash[i],
1353                                     cl_common.hnode) {
1354                        if (arg->count < arg->skip) {
1355                                arg->count++;
1356                                continue;
1357                        }
1358                        if (arg->fn(sch, (unsigned long)cl, arg) < 0) {
1359                                arg->stop = 1;
1360                                return;
1361                        }
1362                        arg->count++;
1363                }
1364        }
1365}
1366
1367static void
1368hfsc_schedule_watchdog(struct Qdisc *sch)
1369{
1370        struct hfsc_sched *q = qdisc_priv(sch);
1371        struct hfsc_class *cl;
1372        u64 next_time = 0;
1373
1374        cl = eltree_get_minel(q);
1375        if (cl)
1376                next_time = cl->cl_e;
1377        if (q->root.cl_cfmin != 0) {
1378                if (next_time == 0 || next_time > q->root.cl_cfmin)
1379                        next_time = q->root.cl_cfmin;
1380        }
1381        if (next_time)
1382                qdisc_watchdog_schedule(&q->watchdog, next_time);
1383}
1384
1385static int
1386hfsc_init_qdisc(struct Qdisc *sch, struct nlattr *opt,
1387                struct netlink_ext_ack *extack)
1388{
1389        struct hfsc_sched *q = qdisc_priv(sch);
1390        struct tc_hfsc_qopt *qopt;
1391        int err;
1392
1393        qdisc_watchdog_init(&q->watchdog, sch);
1394
1395        if (!opt || nla_len(opt) < sizeof(*qopt))
1396                return -EINVAL;
1397        qopt = nla_data(opt);
1398
1399        q->defcls = qopt->defcls;
1400        err = qdisc_class_hash_init(&q->clhash);
1401        if (err < 0)
1402                return err;
1403        q->eligible = RB_ROOT;
1404
1405        err = tcf_block_get(&q->root.block, &q->root.filter_list, sch, extack);
1406        if (err)
1407                return err;
1408
1409        q->root.cl_common.classid = sch->handle;
1410        q->root.sched   = q;
1411        q->root.qdisc = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops,
1412                                          sch->handle, NULL);
1413        if (q->root.qdisc == NULL)
1414                q->root.qdisc = &noop_qdisc;
1415        else
1416                qdisc_hash_add(q->root.qdisc, true);
1417        INIT_LIST_HEAD(&q->root.children);
1418        q->root.vt_tree = RB_ROOT;
1419        q->root.cf_tree = RB_ROOT;
1420
1421        qdisc_class_hash_insert(&q->clhash, &q->root.cl_common);
1422        qdisc_class_hash_grow(sch, &q->clhash);
1423
1424        return 0;
1425}
1426
1427static int
1428hfsc_change_qdisc(struct Qdisc *sch, struct nlattr *opt,
1429                  struct netlink_ext_ack *extack)
1430{
1431        struct hfsc_sched *q = qdisc_priv(sch);
1432        struct tc_hfsc_qopt *qopt;
1433
1434        if (opt == NULL || nla_len(opt) < sizeof(*qopt))
1435                return -EINVAL;
1436        qopt = nla_data(opt);
1437
1438        sch_tree_lock(sch);
1439        q->defcls = qopt->defcls;
1440        sch_tree_unlock(sch);
1441
1442        return 0;
1443}
1444
1445static void
1446hfsc_reset_class(struct hfsc_class *cl)
1447{
1448        cl->cl_total        = 0;
1449        cl->cl_cumul        = 0;
1450        cl->cl_d            = 0;
1451        cl->cl_e            = 0;
1452        cl->cl_vt           = 0;
1453        cl->cl_vtadj        = 0;
1454        cl->cl_cvtmin       = 0;
1455        cl->cl_cvtoff       = 0;
1456        cl->cl_vtperiod     = 0;
1457        cl->cl_parentperiod = 0;
1458        cl->cl_f            = 0;
1459        cl->cl_myf          = 0;
1460        cl->cl_cfmin        = 0;
1461        cl->cl_nactive      = 0;
1462
1463        cl->vt_tree = RB_ROOT;
1464        cl->cf_tree = RB_ROOT;
1465        qdisc_reset(cl->qdisc);
1466
1467        if (cl->cl_flags & HFSC_RSC)
1468                rtsc_init(&cl->cl_deadline, &cl->cl_rsc, 0, 0);
1469        if (cl->cl_flags & HFSC_FSC)
1470                rtsc_init(&cl->cl_virtual, &cl->cl_fsc, 0, 0);
1471        if (cl->cl_flags & HFSC_USC)
1472                rtsc_init(&cl->cl_ulimit, &cl->cl_usc, 0, 0);
1473}
1474
1475static void
1476hfsc_reset_qdisc(struct Qdisc *sch)
1477{
1478        struct hfsc_sched *q = qdisc_priv(sch);
1479        struct hfsc_class *cl;
1480        unsigned int i;
1481
1482        for (i = 0; i < q->clhash.hashsize; i++) {
1483                hlist_for_each_entry(cl, &q->clhash.hash[i], cl_common.hnode)
1484                        hfsc_reset_class(cl);
1485        }
1486        q->eligible = RB_ROOT;
1487        qdisc_watchdog_cancel(&q->watchdog);
1488        sch->qstats.backlog = 0;
1489        sch->q.qlen = 0;
1490}
1491
1492static void
1493hfsc_destroy_qdisc(struct Qdisc *sch)
1494{
1495        struct hfsc_sched *q = qdisc_priv(sch);
1496        struct hlist_node *next;
1497        struct hfsc_class *cl;
1498        unsigned int i;
1499
1500        for (i = 0; i < q->clhash.hashsize; i++) {
1501                hlist_for_each_entry(cl, &q->clhash.hash[i], cl_common.hnode) {
1502                        tcf_block_put(cl->block);
1503                        cl->block = NULL;
1504                }
1505        }
1506        for (i = 0; i < q->clhash.hashsize; i++) {
1507                hlist_for_each_entry_safe(cl, next, &q->clhash.hash[i],
1508                                          cl_common.hnode)
1509                        hfsc_destroy_class(sch, cl);
1510        }
1511        qdisc_class_hash_destroy(&q->clhash);
1512        qdisc_watchdog_cancel(&q->watchdog);
1513}
1514
1515static int
1516hfsc_dump_qdisc(struct Qdisc *sch, struct sk_buff *skb)
1517{
1518        struct hfsc_sched *q = qdisc_priv(sch);
1519        unsigned char *b = skb_tail_pointer(skb);
1520        struct tc_hfsc_qopt qopt;
1521
1522        qopt.defcls = q->defcls;
1523        if (nla_put(skb, TCA_OPTIONS, sizeof(qopt), &qopt))
1524                goto nla_put_failure;
1525        return skb->len;
1526
1527 nla_put_failure:
1528        nlmsg_trim(skb, b);
1529        return -1;
1530}
1531
1532static int
1533hfsc_enqueue(struct sk_buff *skb, struct Qdisc *sch, struct sk_buff **to_free)
1534{
1535        unsigned int len = qdisc_pkt_len(skb);
1536        struct hfsc_class *cl;
1537        int err;
1538        bool first;
1539
1540        cl = hfsc_classify(skb, sch, &err);
1541        if (cl == NULL) {
1542                if (err & __NET_XMIT_BYPASS)
1543                        qdisc_qstats_drop(sch);
1544                __qdisc_drop(skb, to_free);
1545                return err;
1546        }
1547
1548        first = !cl->qdisc->q.qlen;
1549        err = qdisc_enqueue(skb, cl->qdisc, to_free);
1550        if (unlikely(err != NET_XMIT_SUCCESS)) {
1551                if (net_xmit_drop_count(err)) {
1552                        cl->qstats.drops++;
1553                        qdisc_qstats_drop(sch);
1554                }
1555                return err;
1556        }
1557
1558        if (first) {
1559                if (cl->cl_flags & HFSC_RSC)
1560                        init_ed(cl, len);
1561                if (cl->cl_flags & HFSC_FSC)
1562                        init_vf(cl, len);
1563                /*
1564                 * If this is the first packet, isolate the head so an eventual
1565                 * head drop before the first dequeue operation has no chance
1566                 * to invalidate the deadline.
1567                 */
1568                if (cl->cl_flags & HFSC_RSC)
1569                        cl->qdisc->ops->peek(cl->qdisc);
1570
1571        }
1572
1573        sch->qstats.backlog += len;
1574        sch->q.qlen++;
1575
1576        return NET_XMIT_SUCCESS;
1577}
1578
1579static struct sk_buff *
1580hfsc_dequeue(struct Qdisc *sch)
1581{
1582        struct hfsc_sched *q = qdisc_priv(sch);
1583        struct hfsc_class *cl;
1584        struct sk_buff *skb;
1585        u64 cur_time;
1586        unsigned int next_len;
1587        int realtime = 0;
1588
1589        if (sch->q.qlen == 0)
1590                return NULL;
1591
1592        cur_time = psched_get_time();
1593
1594        /*
1595         * if there are eligible classes, use real-time criteria.
1596         * find the class with the minimum deadline among
1597         * the eligible classes.
1598         */
1599        cl = eltree_get_mindl(q, cur_time);
1600        if (cl) {
1601                realtime = 1;
1602        } else {
1603                /*
1604                 * use link-sharing criteria
1605                 * get the class with the minimum vt in the hierarchy
1606                 */
1607                cl = vttree_get_minvt(&q->root, cur_time);
1608                if (cl == NULL) {
1609                        qdisc_qstats_overlimit(sch);
1610                        hfsc_schedule_watchdog(sch);
1611                        return NULL;
1612                }
1613        }
1614
1615        skb = qdisc_dequeue_peeked(cl->qdisc);
1616        if (skb == NULL) {
1617                qdisc_warn_nonwc("HFSC", cl->qdisc);
1618                return NULL;
1619        }
1620
1621        bstats_update(&cl->bstats, skb);
1622        update_vf(cl, qdisc_pkt_len(skb), cur_time);
1623        if (realtime)
1624                cl->cl_cumul += qdisc_pkt_len(skb);
1625
1626        if (cl->cl_flags & HFSC_RSC) {
1627                if (cl->qdisc->q.qlen != 0) {
1628                        /* update ed */
1629                        next_len = qdisc_peek_len(cl->qdisc);
1630                        if (realtime)
1631                                update_ed(cl, next_len);
1632                        else
1633                                update_d(cl, next_len);
1634                } else {
1635                        /* the class becomes passive */
1636                        eltree_remove(cl);
1637                }
1638        }
1639
1640        qdisc_bstats_update(sch, skb);
1641        qdisc_qstats_backlog_dec(sch, skb);
1642        sch->q.qlen--;
1643
1644        return skb;
1645}
1646
1647static const struct Qdisc_class_ops hfsc_class_ops = {
1648        .change         = hfsc_change_class,
1649        .delete         = hfsc_delete_class,
1650        .graft          = hfsc_graft_class,
1651        .leaf           = hfsc_class_leaf,
1652        .qlen_notify    = hfsc_qlen_notify,
1653        .find           = hfsc_search_class,
1654        .bind_tcf       = hfsc_bind_tcf,
1655        .unbind_tcf     = hfsc_unbind_tcf,
1656        .tcf_block      = hfsc_tcf_block,
1657        .dump           = hfsc_dump_class,
1658        .dump_stats     = hfsc_dump_class_stats,
1659        .walk           = hfsc_walk
1660};
1661
1662static struct Qdisc_ops hfsc_qdisc_ops __read_mostly = {
1663        .id             = "hfsc",
1664        .init           = hfsc_init_qdisc,
1665        .change         = hfsc_change_qdisc,
1666        .reset          = hfsc_reset_qdisc,
1667        .destroy        = hfsc_destroy_qdisc,
1668        .dump           = hfsc_dump_qdisc,
1669        .enqueue        = hfsc_enqueue,
1670        .dequeue        = hfsc_dequeue,
1671        .peek           = qdisc_peek_dequeued,
1672        .cl_ops         = &hfsc_class_ops,
1673        .priv_size      = sizeof(struct hfsc_sched),
1674        .owner          = THIS_MODULE
1675};
1676
1677static int __init
1678hfsc_init(void)
1679{
1680        return register_qdisc(&hfsc_qdisc_ops);
1681}
1682
1683static void __exit
1684hfsc_cleanup(void)
1685{
1686        unregister_qdisc(&hfsc_qdisc_ops);
1687}
1688
1689MODULE_LICENSE("GPL");
1690module_init(hfsc_init);
1691module_exit(hfsc_cleanup);
1692
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.