net/sched/sch_hfsc.c

   1 /*
   2  * Copyright (c) 2003 Patrick McHardy, <kaber@trash.net>
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License
   6  * as published by the Free Software Foundation; either version 2
   7  * of the License, or (at your option) any later version.
   8  *
   9  * 2003-10-17 - Ported from altq
  10  */
  11 /*
  12  * Copyright (c) 1997-1999 Carnegie Mellon University. All Rights Reserved.
  13  *
  14  * Permission to use, copy, modify, and distribute this software and
  15  * its documentation is hereby granted (including for commercial or
  16  * for-profit use), provided that both the copyright notice and this
  17  * permission notice appear in all copies of the software, derivative
  18  * works, or modified versions, and any portions thereof.
  19  *
  20  * THIS SOFTWARE IS EXPERIMENTAL AND IS KNOWN TO HAVE BUGS, SOME OF
  21  * WHICH MAY HAVE SERIOUS CONSEQUENCES.  CARNEGIE MELLON PROVIDES THIS
  22  * SOFTWARE IN ITS ``AS IS'' CONDITION, AND ANY EXPRESS OR IMPLIED
  23  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  25  * DISCLAIMED.  IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY BE LIABLE
  26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  27  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
  28  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  29  * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  30  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  31  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
  32  * USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
  33  * DAMAGE.
  34  *
  35  * Carnegie Mellon encourages (but does not require) users of this
  36  * software to return any improvements or extensions that they make,
  37  * and to grant Carnegie Mellon the rights to redistribute these
  38  * changes without encumbrance.
  39  */
  40 /*
  41  * H-FSC is described in Proceedings of SIGCOMM'97,
  42  * "A Hierarchical Fair Service Curve Algorithm for Link-Sharing,
  43  * Real-Time and Priority Service"
  44  * by Ion Stoica, Hui Zhang, and T. S. Eugene Ng.
  45  *
  46  * Oleg Cherevko <olwi@aq.ml.com.ua> added the upperlimit for link-sharing.
  47  * when a class has an upperlimit, the fit-time is computed from the
  48  * upperlimit service curve.  the link-sharing scheduler does not schedule
  49  * a class whose fit-time exceeds the current time.
  50  */
  51
  52 #include <linux/kernel.h>
  53 #include <linux/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
  84 struct 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 */
  95 struct 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
 107 enum hfsc_class_flags
 108 {
 109         HFSC_RSC = 0x1,
 110         HFSC_FSC = 0x2,
 111         HFSC_USC = 0x4
 112 };
 113
 114 struct 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
 179 struct 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 sk_buff_head requeue;            /* requeued packet */
 188         struct qdisc_watchdog watchdog;         /* watchdog timer */
 189 };
 190
 191 #define HT_INFINITY     0xffffffffffffffffULL   /* infinite time value */
 192
 193
 194 /*
 195  * eligible tree holds backlogged classes being sorted by their eligible times.
 196  * there is one eligible tree per hfsc instance.
 197  */
 198
 199 static void
 200 eltree_insert(struct hfsc_class *cl)
 201 {
 202         struct rb_node **p = &cl->sched->eligible.rb_node;
 203         struct rb_node *parent = NULL;
 204         struct hfsc_class *cl1;
 205
 206         while (*p != NULL) {
 207                 parent = *p;
 208                 cl1 = rb_entry(parent, struct hfsc_class, el_node);
 209                 if (cl->cl_e >= cl1->cl_e)
 210                         p = &parent->rb_right;
 211                 else
 212                         p = &parent->rb_left;
 213         }
 214         rb_link_node(&cl->el_node, parent, p);
 215         rb_insert_color(&cl->el_node, &cl->sched->eligible);
 216 }
 217
 218 static inline void
 219 eltree_remove(struct hfsc_class *cl)
 220 {
 221         rb_erase(&cl->el_node, &cl->sched->eligible);
 222 }
 223
 224 static inline void
 225 eltree_update(struct hfsc_class *cl)
 226 {
 227         eltree_remove(cl);
 228         eltree_insert(cl);
 229 }
 230
 231 /* find the class with the minimum deadline among the eligible classes */
 232 static inline struct hfsc_class *
 233 eltree_get_mindl(struct hfsc_sched *q, u64 cur_time)
 234 {
 235         struct hfsc_class *p, *cl = NULL;
 236         struct rb_node *n;
 237
 238         for (n = rb_first(&q->eligible); n != NULL; n = rb_next(n)) {
 239                 p = rb_entry(n, struct hfsc_class, el_node);
 240                 if (p->cl_e > cur_time)
 241                         break;
 242                 if (cl == NULL || p->cl_d < cl->cl_d)
 243                         cl = p;
 244         }
 245         return cl;
 246 }
 247
 248 /* find the class with minimum eligible time among the eligible classes */
 249 static inline struct hfsc_class *
 250 eltree_get_minel(struct hfsc_sched *q)
 251 {
 252         struct rb_node *n;
 253
 254         n = rb_first(&q->eligible);
 255         if (n == NULL)
 256                 return NULL;
 257         return rb_entry(n, struct hfsc_class, el_node);
 258 }
 259
 260 /*
 261  * vttree holds holds backlogged child classes being sorted by their virtual
 262  * time. each intermediate class has one vttree.
 263  */
 264 static void
 265 vttree_insert(struct hfsc_class *cl)
 266 {
 267         struct rb_node **p = &cl->cl_parent->vt_tree.rb_node;
 268         struct rb_node *parent = NULL;
 269         struct hfsc_class *cl1;
 270
 271         while (*p != NULL) {
 272                 parent = *p;
 273                 cl1 = rb_entry(parent, struct hfsc_class, vt_node);
 274                 if (cl->cl_vt >= cl1->cl_vt)
 275                         p = &parent->rb_right;
 276                 else
 277                         p = &parent->rb_left;
 278         }
 279         rb_link_node(&cl->vt_node, parent, p);
 280         rb_insert_color(&cl->vt_node, &cl->cl_parent->vt_tree);
 281 }
 282
 283 static inline void
 284 vttree_remove(struct hfsc_class *cl)
 285 {
 286         rb_erase(&cl->vt_node, &cl->cl_parent->vt_tree);
 287 }
 288
 289 static inline void
 290 vttree_update(struct hfsc_class *cl)
 291 {
 292         vttree_remove(cl);
 293         vttree_insert(cl);
 294 }
 295
 296 static inline struct hfsc_class *
 297 vttree_firstfit(struct hfsc_class *cl, u64 cur_time)
 298 {
 299         struct hfsc_class *p;
 300         struct rb_node *n;
 301
 302         for (n = rb_first(&cl->vt_tree); n != NULL; n = rb_next(n)) {
 303                 p = rb_entry(n, struct hfsc_class, vt_node);
 304                 if (p->cl_f <= cur_time)
 305                         return p;
 306         }
 307         return NULL;
 308 }
 309
 310 /*
 311  * get the leaf class with the minimum vt in the hierarchy
 312  */
 313 static struct hfsc_class *
 314 vttree_get_minvt(struct hfsc_class *cl, u64 cur_time)
 315 {
 316         /* if root-class's cfmin is bigger than cur_time nothing to do */
 317         if (cl->cl_cfmin > cur_time)
 318                 return NULL;
 319
 320         while (cl->level > 0) {
 321                 cl = vttree_firstfit(cl, cur_time);
 322                 if (cl == NULL)
 323                         return NULL;
 324                 /*
 325                  * update parent's cl_cvtmin.
 326                  */
 327                 if (cl->cl_parent->cl_cvtmin < cl->cl_vt)
 328                         cl->cl_parent->cl_cvtmin = cl->cl_vt;
 329         }
 330         return cl;
 331 }
 332
 333 static void
 334 cftree_insert(struct hfsc_class *cl)
 335 {
 336         struct rb_node **p = &cl->cl_parent->cf_tree.rb_node;
 337         struct rb_node *parent = NULL;
 338         struct hfsc_class *cl1;
 339
 340         while (*p != NULL) {
 341                 parent = *p;
 342                 cl1 = rb_entry(parent, struct hfsc_class, cf_node);
 343                 if (cl->cl_f >= cl1->cl_f)
 344                         p = &parent->rb_right;
 345                 else
 346                         p = &parent->rb_left;
 347         }
 348         rb_link_node(&cl->cf_node, parent, p);
 349         rb_insert_color(&cl->cf_node, &cl->cl_parent->cf_tree);
 350 }
 351
 352 static inline void
 353 cftree_remove(struct hfsc_class *cl)
 354 {
 355         rb_erase(&cl->cf_node, &cl->cl_parent->cf_tree);
 356 }
 357
 358 static inline void
 359 cftree_update(struct hfsc_class *cl)
 360 {
 361         cftree_remove(cl);
 362         cftree_insert(cl);
 363 }
 364
 365 /*
 366  * service curve support functions
 367  *
 368  *  external service curve parameters
 369  *      m: bps
 370  *      d: us
 371  *  internal service curve parameters
 372  *      sm: (bytes/psched_us) << SM_SHIFT
 373  *      ism: (psched_us/byte) << ISM_SHIFT
 374  *      dx: psched_us
 375  *
 376  * The clock source resolution with ktime is 1.024us.
 377  *
 378  * sm and ism are scaled in order to keep effective digits.
 379  * SM_SHIFT and ISM_SHIFT are selected to keep at least 4 effective
 380  * digits in decimal using the following table.
 381  *
 382  *  bits/sec      100Kbps     1Mbps     10Mbps     100Mbps    1Gbps
 383  *  ------------+-------------------------------------------------------
 384  *  bytes/1.024us 12.8e-3    128e-3     1280e-3    12800e-3   128000e-3
 385  *
 386  *  1.024us/byte  78.125     7.8125     0.78125    0.078125   0.0078125
 387  */
 388 #define SM_SHIFT        20
 389 #define ISM_SHIFT       18
 390
 391 #define SM_MASK         ((1ULL << SM_SHIFT) - 1)
 392 #define ISM_MASK        ((1ULL << ISM_SHIFT) - 1)
 393
 394 static inline u64
 395 seg_x2y(u64 x, u64 sm)
 396 {
 397         u64 y;
 398
 399         /*
 400          * compute
 401          *      y = x * sm >> SM_SHIFT
 402          * but divide it for the upper and lower bits to avoid overflow
 403          */
 404         y = (x >> SM_SHIFT) * sm + (((x & SM_MASK) * sm) >> SM_SHIFT);
 405         return y;
 406 }
 407
 408 static inline u64
 409 seg_y2x(u64 y, u64 ism)
 410 {
 411         u64 x;
 412
 413         if (y == 0)
 414                 x = 0;
 415         else if (ism == HT_INFINITY)
 416                 x = HT_INFINITY;
 417         else {
 418                 x = (y >> ISM_SHIFT) * ism
 419                     + (((y & ISM_MASK) * ism) >> ISM_SHIFT);
 420         }
 421         return x;
 422 }
 423
 424 /* Convert m (bps) into sm (bytes/psched us) */
 425 static u64
 426 m2sm(u32 m)
 427 {
 428         u64 sm;
 429
 430         sm = ((u64)m << SM_SHIFT);
 431         sm += PSCHED_TICKS_PER_SEC - 1;
 432         do_div(sm, PSCHED_TICKS_PER_SEC);
 433         return sm;
 434 }
 435
 436 /* convert m (bps) into ism (psched us/byte) */
 437 static u64
 438 m2ism(u32 m)
 439 {
 440         u64 ism;
 441
 442         if (m == 0)
 443                 ism = HT_INFINITY;
 444         else {
 445                 ism = ((u64)PSCHED_TICKS_PER_SEC << ISM_SHIFT);
 446                 ism += m - 1;
 447                 do_div(ism, m);
 448         }
 449         return ism;
 450 }
 451
 452 /* convert d (us) into dx (psched us) */
 453 static u64
 454 d2dx(u32 d)
 455 {
 456         u64 dx;
 457
 458         dx = ((u64)d * PSCHED_TICKS_PER_SEC);
 459         dx += USEC_PER_SEC - 1;
 460         do_div(dx, USEC_PER_SEC);
 461         return dx;
 462 }
 463
 464 /* convert sm (bytes/psched us) into m (bps) */
 465 static u32
 466 sm2m(u64 sm)
 467 {
 468         u64 m;
 469
 470         m = (sm * PSCHED_TICKS_PER_SEC) >> SM_SHIFT;
 471         return (u32)m;
 472 }
 473
 474 /* convert dx (psched us) into d (us) */
 475 static u32
 476 dx2d(u64 dx)
 477 {
 478         u64 d;
 479
 480         d = dx * USEC_PER_SEC;
 481         do_div(d, PSCHED_TICKS_PER_SEC);
 482         return (u32)d;
 483 }
 484
 485 static void
 486 sc2isc(struct tc_service_curve *sc, struct internal_sc *isc)
 487 {
 488         isc->sm1  = m2sm(sc->m1);
 489         isc->ism1 = m2ism(sc->m1);
 490         isc->dx   = d2dx(sc->d);
 491         isc->dy   = seg_x2y(isc->dx, isc->sm1);
 492         isc->sm2  = m2sm(sc->m2);
 493         isc->ism2 = m2ism(sc->m2);
 494 }
 495
 496 /*
 497  * initialize the runtime service curve with the given internal
 498  * service curve starting at (x, y).
 499  */
 500 static void
 501 rtsc_init(struct runtime_sc *rtsc, struct internal_sc *isc, u64 x, u64 y)
 502 {
 503         rtsc->x    = x;
 504         rtsc->y    = y;
 505         rtsc->sm1  = isc->sm1;
 506         rtsc->ism1 = isc->ism1;
 507         rtsc->dx   = isc->dx;
 508         rtsc->dy   = isc->dy;
 509         rtsc->sm2  = isc->sm2;
 510         rtsc->ism2 = isc->ism2;
 511 }
 512
 513 /*
 514  * calculate the y-projection of the runtime service curve by the
 515  * given x-projection value
 516  */
 517 static u64
 518 rtsc_y2x(struct runtime_sc *rtsc, u64 y)
 519 {
 520         u64 x;
 521
 522         if (y < rtsc->y)
 523                 x = rtsc->x;
 524         else if (y <= rtsc->y + rtsc->dy) {
 525                 /* x belongs to the 1st segment */
 526                 if (rtsc->dy == 0)
 527                         x = rtsc->x + rtsc->dx;
 528                 else
 529                         x = rtsc->x + seg_y2x(y - rtsc->y, rtsc->ism1);
 530         } else {
 531                 /* x belongs to the 2nd segment */
 532                 x = rtsc->x + rtsc->dx
 533                     + seg_y2x(y - rtsc->y - rtsc->dy, rtsc->ism2);
 534         }
 535         return x;
 536 }
 537
 538 static u64
 539 rtsc_x2y(struct runtime_sc *rtsc, u64 x)
 540 {
 541         u64 y;
 542
 543         if (x <= rtsc->x)
 544                 y = rtsc->y;
 545         else if (x <= rtsc->x + rtsc->dx)
 546                 /* y belongs to the 1st segment */
 547                 y = rtsc->y + seg_x2y(x - rtsc->x, rtsc->sm1);
 548         else
 549                 /* y belongs to the 2nd segment */
 550                 y = rtsc->y + rtsc->dy
 551                     + seg_x2y(x - rtsc->x - rtsc->dx, rtsc->sm2);
 552         return y;
 553 }
 554
 555 /*
 556  * update the runtime service curve by taking the minimum of the current
 557  * runtime service curve and the service curve starting at (x, y).
 558  */
 559 static void
 560 rtsc_min(struct runtime_sc *rtsc, struct internal_sc *isc, u64 x, u64 y)
 561 {
 562         u64 y1, y2, dx, dy;
 563         u32 dsm;
 564
 565         if (isc->sm1 <= isc->sm2) {
 566                 /* service curve is convex */
 567                 y1 = rtsc_x2y(rtsc, x);
 568                 if (y1 < y)
 569                         /* the current rtsc is smaller */
 570                         return;
 571                 rtsc->x = x;
 572                 rtsc->y = y;
 573                 return;
 574         }
 575
 576         /*
 577          * service curve is concave
 578          * compute the two y values of the current rtsc
 579          *      y1: at x
 580          *      y2: at (x + dx)
 581          */
 582         y1 = rtsc_x2y(rtsc, x);
 583         if (y1 <= y) {
 584                 /* rtsc is below isc, no change to rtsc */
 585                 return;
 586         }
 587
 588         y2 = rtsc_x2y(rtsc, x + isc->dx);
 589         if (y2 >= y + isc->dy) {
 590                 /* rtsc is above isc, replace rtsc by isc */
 591                 rtsc->x = x;
 592                 rtsc->y = y;
 593                 rtsc->dx = isc->dx;
 594                 rtsc->dy = isc->dy;
 595                 return;
 596         }
 597
 598         /*
 599          * the two curves intersect
 600          * compute the offsets (dx, dy) using the reverse
 601          * function of seg_x2y()
 602          *      seg_x2y(dx, sm1) == seg_x2y(dx, sm2) + (y1 - y)
 603          */
 604         dx = (y1 - y) << SM_SHIFT;
 605         dsm = isc->sm1 - isc->sm2;
 606         do_div(dx, dsm);
 607         /*
 608          * check if (x, y1) belongs to the 1st segment of rtsc.
 609          * if so, add the offset.
 610          */
 611         if (rtsc->x + rtsc->dx > x)
 612                 dx += rtsc->x + rtsc->dx - x;
 613         dy = seg_x2y(dx, isc->sm1);
 614
 615         rtsc->x = x;
 616         rtsc->y = y;
 617         rtsc->dx = dx;
 618         rtsc->dy = dy;
 619         return;
 620 }
 621
 622 static void
 623 init_ed(struct hfsc_class *cl, unsigned int next_len)
 624 {
 625         u64 cur_time = psched_get_time();
 626
 627         /* update the deadline curve */
 628         rtsc_min(&cl->cl_deadline, &cl->cl_rsc, cur_time, cl->cl_cumul);
 629
 630         /*
 631          * update the eligible curve.
 632          * for concave, it is equal to the deadline curve.
 633          * for convex, it is a linear curve with slope m2.
 634          */
 635         cl->cl_eligible = cl->cl_deadline;
 636         if (cl->cl_rsc.sm1 <= cl->cl_rsc.sm2) {
 637                 cl->cl_eligible.dx = 0;
 638                 cl->cl_eligible.dy = 0;
 639         }
 640
 641         /* compute e and d */
 642         cl->cl_e = rtsc_y2x(&cl->cl_eligible, cl->cl_cumul);
 643         cl->cl_d = rtsc_y2x(&cl->cl_deadline, cl->cl_cumul + next_len);
 644
 645         eltree_insert(cl);
 646 }
 647
 648 static void
 649 update_ed(struct hfsc_class *cl, unsigned int next_len)
 650 {
 651         cl->cl_e = rtsc_y2x(&cl->cl_eligible, cl->cl_cumul);
 652         cl->cl_d = rtsc_y2x(&cl->cl_deadline, cl->cl_cumul + next_len);
 653
 654         eltree_update(cl);
 655 }
 656
 657 static inline void
 658 update_d(struct hfsc_class *cl, unsigned int next_len)
 659 {
 660         cl->cl_d = rtsc_y2x(&cl->cl_deadline, cl->cl_cumul + next_len);
 661 }
 662
 663 static inline void
 664 update_cfmin(struct hfsc_class *cl)
 665 {
 666         struct rb_node *n = rb_first(&cl->cf_tree);
 667         struct hfsc_class *p;
 668
 669         if (n == NULL) {
 670                 cl->cl_cfmin = 0;
 671                 return;
 672         }
 673         p = rb_entry(n, struct hfsc_class, cf_node);
 674         cl->cl_cfmin = p->cl_f;
 675 }
 676
 677 static void
 678 init_vf(struct hfsc_class *cl, unsigned int len)
 679 {
 680         struct hfsc_class *max_cl;
 681         struct rb_node *n;
 682         u64 vt, f, cur_time;
 683         int go_active;
 684
 685         cur_time = 0;
 686         go_active = 1;
 687         for (; cl->cl_parent != NULL; cl = cl->cl_parent) {
 688                 if (go_active && cl->cl_nactive++ == 0)
 689                         go_active = 1;
 690                 else
 691                         go_active = 0;
 692
 693                 if (go_active) {
 694                         n = rb_last(&cl->cl_parent->vt_tree);
 695                         if (n != NULL) {
 696                                 max_cl = rb_entry(n, struct hfsc_class,vt_node);
 697                                 /*
 698                                  * set vt to the average of the min and max
 699                                  * classes.  if the parent's period didn't
 700                                  * change, don't decrease vt of the class.
 701                                  */
 702                                 vt = max_cl->cl_vt;
 703                                 if (cl->cl_parent->cl_cvtmin != 0)
 704                                         vt = (cl->cl_parent->cl_cvtmin + vt)/2;
 705
 706                                 if (cl->cl_parent->cl_vtperiod !=
 707                                     cl->cl_parentperiod || vt > cl->cl_vt)
 708                                         cl->cl_vt = vt;
 709                         } else {
 710                                 /*
 711                                  * first child for a new parent backlog period.
 712                                  * add parent's cvtmax to cvtoff to make a new
 713                                  * vt (vtoff + vt) larger than the vt in the
 714                                  * last period for all children.
 715                                  */
 716                                 vt = cl->cl_parent->cl_cvtmax;
 717                                 cl->cl_parent->cl_cvtoff += vt;
 718                                 cl->cl_parent->cl_cvtmax = 0;
 719                                 cl->cl_parent->cl_cvtmin = 0;
 720                                 cl->cl_vt = 0;
 721                         }
 722
 723                         cl->cl_vtoff = cl->cl_parent->cl_cvtoff -
 724                                                         cl->cl_pcvtoff;
 725
 726                         /* update the virtual curve */
 727                         vt = cl->cl_vt + cl->cl_vtoff;
 728                         rtsc_min(&cl->cl_virtual, &cl->cl_fsc, vt,
 729                                                       cl->cl_total);
 730                         if (cl->cl_virtual.x == vt) {
 731                                 cl->cl_virtual.x -= cl->cl_vtoff;
 732                                 cl->cl_vtoff = 0;
 733                         }
 734                         cl->cl_vtadj = 0;
 735
 736                         cl->cl_vtperiod++;  /* increment vt period */
 737                         cl->cl_parentperiod = cl->cl_parent->cl_vtperiod;
 738                         if (cl->cl_parent->cl_nactive == 0)
 739                                 cl->cl_parentperiod++;
 740                         cl->cl_f = 0;
 741
 742                         vttree_insert(cl);
 743                         cftree_insert(cl);
 744
 745                         if (cl->cl_flags & HFSC_USC) {
 746                                 /* class has upper limit curve */
 747                                 if (cur_time == 0)
 748                                         cur_time = psched_get_time();
 749
 750                                 /* update the ulimit curve */
 751                                 rtsc_min(&cl->cl_ulimit, &cl->cl_usc, cur_time,
 752                                          cl->cl_total);
 753                                 /* compute myf */
 754                                 cl->cl_myf = rtsc_y2x(&cl->cl_ulimit,
 755                                                       cl->cl_total);
 756                                 cl->cl_myfadj = 0;
 757                         }
 758                 }
 759
 760                 f = max(cl->cl_myf, cl->cl_cfmin);
 761                 if (f != cl->cl_f) {
 762                         cl->cl_f = f;
 763                         cftree_update(cl);
 764                         update_cfmin(cl->cl_parent);
 765                 }
 766         }
 767 }
 768
 769 static void
 770 update_vf(struct hfsc_class *cl, unsigned int len, u64 cur_time)
 771 {
 772         u64 f; /* , myf_bound, delta; */
 773         int go_passive = 0;
 774
 775         if (cl->qdisc->q.qlen == 0 && cl->cl_flags & HFSC_FSC)
 776                 go_passive = 1;
 777
 778         for (; cl->cl_parent != NULL; cl = cl->cl_parent) {
 779                 cl->cl_total += len;
 780
 781                 if (!(cl->cl_flags & HFSC_FSC) || cl->cl_nactive == 0)
 782                         continue;
 783
 784                 if (go_passive && --cl->cl_nactive == 0)
 785                         go_passive = 1;
 786                 else
 787                         go_passive = 0;
 788
 789                 if (go_passive) {
 790                         /* no more active child, going passive */
 791
 792                         /* update cvtmax of the parent class */
 793                         if (cl->cl_vt > cl->cl_parent->cl_cvtmax)
 794                                 cl->cl_parent->cl_cvtmax = cl->cl_vt;
 795
 796                         /* remove this class from the vt tree */
 797                         vttree_remove(cl);
 798
 799                         cftree_remove(cl);
 800                         update_cfmin(cl->cl_parent);
 801
 802                         continue;
 803                 }
 804
 805                 /*
 806                  * update vt and f
 807                  */
 808                 cl->cl_vt = rtsc_y2x(&cl->cl_virtual, cl->cl_total)
 809                             - cl->cl_vtoff + cl->cl_vtadj;
 810
 811                 /*
 812                  * if vt of the class is smaller than cvtmin,
 813                  * the class was skipped in the past due to non-fit.
 814                  * if so, we need to adjust vtadj.
 815                  */
 816                 if (cl->cl_vt < cl->cl_parent->cl_cvtmin) {
 817                         cl->cl_vtadj += cl->cl_parent->cl_cvtmin - cl->cl_vt;
 818                         cl->cl_vt = cl->cl_parent->cl_cvtmin;
 819                 }
 820
 821                 /* update the vt tree */
 822                 vttree_update(cl);
 823
 824                 if (cl->cl_flags & HFSC_USC) {
 825                         cl->cl_myf = cl->cl_myfadj + rtsc_y2x(&cl->cl_ulimit,
 826                                                               cl->cl_total);
 827 #if 0
 828                         /*
 829                          * This code causes classes to stay way under their
 830                          * limit when multiple classes are used at gigabit
 831                          * speed. needs investigation. -kaber
 832                          */
 833                         /*
 834                          * if myf lags behind by more than one clock tick
 835                          * from the current time, adjust myfadj to prevent
 836                          * a rate-limited class from going greedy.
 837                          * in a steady state under rate-limiting, myf
 838                          * fluctuates within one clock tick.
 839                          */
 840                         myf_bound = cur_time - PSCHED_JIFFIE2US(1);
 841                         if (cl->cl_myf < myf_bound) {
 842                                 delta = cur_time - cl->cl_myf;
 843                                 cl->cl_myfadj += delta;
 844                                 cl->cl_myf += delta;
 845                         }
 846 #endif
 847                 }
 848
 849                 f = max(cl->cl_myf, cl->cl_cfmin);
 850                 if (f != cl->cl_f) {
 851                         cl->cl_f = f;
 852                         cftree_update(cl);
 853                         update_cfmin(cl->cl_parent);
 854                 }
 855         }
 856 }
 857
 858 static void
 859 set_active(struct hfsc_class *cl, unsigned int len)
 860 {
 861         if (cl->cl_flags & HFSC_RSC)
 862                 init_ed(cl, len);
 863         if (cl->cl_flags & HFSC_FSC)
 864                 init_vf(cl, len);
 865
 866         list_add_tail(&cl->dlist, &cl->sched->droplist);
 867 }
 868
 869 static void
 870 set_passive(struct hfsc_class *cl)
 871 {
 872         if (cl->cl_flags & HFSC_RSC)
 873                 eltree_remove(cl);
 874
 875         list_del(&cl->dlist);
 876
 877         /*
 878          * vttree is now handled in update_vf() so that update_vf(cl, 0, 0)
 879          * needs to be called explicitly to remove a class from vttree.
 880          */
 881 }
 882
 883 /*
 884  * hack to get length of first packet in queue.
 885  */
 886 static unsigned int
 887 qdisc_peek_len(struct Qdisc *sch)
 888 {
 889         struct sk_buff *skb;
 890         unsigned int len;
 891
 892         skb = sch->dequeue(sch);
 893         if (skb == NULL) {
 894                 if (net_ratelimit())
 895                         printk("qdisc_peek_len: non work-conserving qdisc ?\n");
 896                 return 0;
 897         }
 898         len = skb->len;
 899         if (unlikely(sch->ops->requeue(skb, sch) != NET_XMIT_SUCCESS)) {
 900                 if (net_ratelimit())
 901                         printk("qdisc_peek_len: failed to requeue\n");
 902                 qdisc_tree_decrease_qlen(sch, 1);
 903                 return 0;
 904         }
 905         return len;
 906 }
 907
 908 static void
 909 hfsc_purge_queue(struct Qdisc *sch, struct hfsc_class *cl)
 910 {
 911         unsigned int len = cl->qdisc->q.qlen;
 912
 913         qdisc_reset(cl->qdisc);
 914         qdisc_tree_decrease_qlen(cl->qdisc, len);
 915 }
 916
 917 static void
 918 hfsc_adjust_levels(struct hfsc_class *cl)
 919 {
 920         struct hfsc_class *p;
 921         unsigned int level;
 922
 923         do {
 924                 level = 0;
 925                 list_for_each_entry(p, &cl->children, siblings) {
 926                         if (p->level >= level)
 927                                 level = p->level + 1;
 928                 }
 929                 cl->level = level;
 930         } while ((cl = cl->cl_parent) != NULL);
 931 }
 932
 933 static inline struct hfsc_class *
 934 hfsc_find_class(u32 classid, struct Qdisc *sch)
 935 {
 936         struct hfsc_sched *q = qdisc_priv(sch);
 937         struct Qdisc_class_common *clc;
 938
 939         clc = qdisc_class_find(&q->clhash, classid);
 940         if (clc == NULL)
 941                 return NULL;
 942         return container_of(clc, struct hfsc_class, cl_common);
 943 }
 944
 945 static void
 946 hfsc_change_rsc(struct hfsc_class *cl, struct tc_service_curve *rsc,
 947                 u64 cur_time)
 948 {
 949         sc2isc(rsc, &cl->cl_rsc);
 950         rtsc_init(&cl->cl_deadline, &cl->cl_rsc, cur_time, cl->cl_cumul);
 951         cl->cl_eligible = cl->cl_deadline;
 952         if (cl->cl_rsc.sm1 <= cl->cl_rsc.sm2) {
 953                 cl->cl_eligible.dx = 0;
 954                 cl->cl_eligible.dy = 0;
 955         }
 956         cl->cl_flags |= HFSC_RSC;
 957 }
 958
 959 static void
 960 hfsc_change_fsc(struct hfsc_class *cl, struct tc_service_curve *fsc)
 961 {
 962         sc2isc(fsc, &cl->cl_fsc);
 963         rtsc_init(&cl->cl_virtual, &cl->cl_fsc, cl->cl_vt, cl->cl_total);
 964         cl->cl_flags |= HFSC_FSC;
 965 }
 966
 967 static void
 968 hfsc_change_usc(struct hfsc_class *cl, struct tc_service_curve *usc,
 969                 u64 cur_time)
 970 {
 971         sc2isc(usc, &cl->cl_usc);
 972         rtsc_init(&cl->cl_ulimit, &cl->cl_usc, cur_time, cl->cl_total);
 973         cl->cl_flags |= HFSC_USC;
 974 }
 975
 976 static const struct nla_policy hfsc_policy[TCA_HFSC_MAX + 1] = {
 977         [TCA_HFSC_RSC]  = { .len = sizeof(struct tc_service_curve) },
 978         [TCA_HFSC_FSC]  = { .len = sizeof(struct tc_service_curve) },
 979         [TCA_HFSC_USC]  = { .len = sizeof(struct tc_service_curve) },
 980 };
 981
 982 static int
 983 hfsc_change_class(struct Qdisc *sch, u32 classid, u32 parentid,
 984                   struct nlattr **tca, unsigned long *arg)
 985 {
 986         struct hfsc_sched *q = qdisc_priv(sch);
 987         struct hfsc_class *cl = (struct hfsc_class *)*arg;
 988         struct hfsc_class *parent = NULL;
 989         struct nlattr *opt = tca[TCA_OPTIONS];
 990         struct nlattr *tb[TCA_HFSC_MAX + 1];
 991         struct tc_service_curve *rsc = NULL, *fsc = NULL, *usc = NULL;
 992         u64 cur_time;
 993         int err;
 994
 995         if (opt == NULL)
 996                 return -EINVAL;
 997
 998         err = nla_parse_nested(tb, TCA_HFSC_MAX, opt, hfsc_policy);
 999         if (err < 0)
1000                 return err;
1001
1002         if (tb[TCA_HFSC_RSC]) {
1003                 rsc = nla_data(tb[TCA_HFSC_RSC]);
1004                 if (rsc->m1 == 0 && rsc->m2 == 0)
1005                         rsc = NULL;
1006         }
1007
1008         if (tb[TCA_HFSC_FSC]) {
1009                 fsc = nla_data(tb[TCA_HFSC_FSC]);
1010                 if (fsc->m1 == 0 && fsc->m2 == 0)
1011                         fsc = NULL;
1012         }
1013
1014         if (tb[TCA_HFSC_USC]) {
1015                 usc = nla_data(tb[TCA_HFSC_USC]);
1016                 if (usc->m1 == 0 && usc->m2 == 0)
1017                         usc = NULL;
1018         }
1019
1020         if (cl != NULL) {
1021                 if (parentid) {
1022                         if (cl->cl_parent &&
1023                             cl->cl_parent->cl_common.classid != parentid)
1024                                 return -EINVAL;
1025                         if (cl->cl_parent == NULL && parentid != TC_H_ROOT)
1026                                 return -EINVAL;
1027                 }
1028                 cur_time = psched_get_time();
1029
1030                 sch_tree_lock(sch);
1031                 if (rsc != NULL)
1032                         hfsc_change_rsc(cl, rsc, cur_time);
1033                 if (fsc != NULL)
1034                         hfsc_change_fsc(cl, fsc);
1035                 if (usc != NULL)
1036                         hfsc_change_usc(cl, usc, cur_time);
1037
1038                 if (cl->qdisc->q.qlen != 0) {
1039                         if (cl->cl_flags & HFSC_RSC)
1040                                 update_ed(cl, qdisc_peek_len(cl->qdisc));
1041                         if (cl->cl_flags & HFSC_FSC)
1042                                 update_vf(cl, 0, cur_time);
1043                 }
1044                 sch_tree_unlock(sch);
1045
1046                 if (tca[TCA_RATE])
1047                         gen_replace_estimator(&cl->bstats, &cl->rate_est,
1048                                               &sch->dev->queue_lock,
1049                                               tca[TCA_RATE]);
1050                 return 0;
1051         }
1052
1053         if (parentid == TC_H_ROOT)
1054                 return -EEXIST;
1055
1056         parent = &q->root;
1057         if (parentid) {
1058                 parent = hfsc_find_class(parentid, sch);
1059                 if (parent == NULL)
1060                         return -ENOENT;
1061         }
1062
1063         if (classid == 0 || TC_H_MAJ(classid ^ sch->handle) != 0)
1064                 return -EINVAL;
1065         if (hfsc_find_class(classid, sch))
1066                 return -EEXIST;
1067
1068         if (rsc == NULL && fsc == NULL)
1069                 return -EINVAL;
1070
1071         cl = kzalloc(sizeof(struct hfsc_class), GFP_KERNEL);
1072         if (cl == NULL)
1073                 return -ENOBUFS;
1074
1075         if (rsc != NULL)
1076                 hfsc_change_rsc(cl, rsc, 0);
1077         if (fsc != NULL)
1078                 hfsc_change_fsc(cl, fsc);
1079         if (usc != NULL)
1080                 hfsc_change_usc(cl, usc, 0);
1081
1082         cl->cl_common.classid = classid;
1083         cl->refcnt    = 1;
1084         cl->sched     = q;
1085         cl->cl_parent = parent;
1086         cl->qdisc = qdisc_create_dflt(sch->dev, &pfifo_qdisc_ops, classid);
1087         if (cl->qdisc == NULL)
1088                 cl->qdisc = &noop_qdisc;
1089         INIT_LIST_HEAD(&cl->children);
1090         cl->vt_tree = RB_ROOT;
1091         cl->cf_tree = RB_ROOT;
1092
1093         sch_tree_lock(sch);
1094         qdisc_class_hash_insert(&q->clhash, &cl->cl_common);
1095         list_add_tail(&cl->siblings, &parent->children);
1096         if (parent->level == 0)
1097                 hfsc_purge_queue(sch, parent);
1098         hfsc_adjust_levels(parent);
1099         cl->cl_pcvtoff = parent->cl_cvtoff;
1100         sch_tree_unlock(sch);
1101
1102         qdisc_class_hash_grow(sch, &q->clhash);
1103
1104         if (tca[TCA_RATE])
1105                 gen_new_estimator(&cl->bstats, &cl->rate_est,
1106                                   &sch->dev->queue_lock, tca[TCA_RATE]);
1107         *arg = (unsigned long)cl;
1108         return 0;
1109 }
1110
1111 static void
1112 hfsc_destroy_class(struct Qdisc *sch, struct hfsc_class *cl)
1113 {
1114         struct hfsc_sched *q = qdisc_priv(sch);
1115
1116         tcf_destroy_chain(&cl->filter_list);
1117         qdisc_destroy(cl->qdisc);
1118         gen_kill_estimator(&cl->bstats, &cl->rate_est);
1119         if (cl != &q->root)
1120                 kfree(cl);
1121 }
1122
1123 static int
1124 hfsc_delete_class(struct Qdisc *sch, unsigned long arg)
1125 {
1126         struct hfsc_sched *q = qdisc_priv(sch);
1127         struct hfsc_class *cl = (struct hfsc_class *)arg;
1128
1129         if (cl->level > 0 || cl->filter_cnt > 0 || cl == &q->root)
1130                 return -EBUSY;
1131
1132         sch_tree_lock(sch);
1133
1134         list_del(&cl->siblings);
1135         hfsc_adjust_levels(cl->cl_parent);
1136
1137         hfsc_purge_queue(sch, cl);
1138         qdisc_class_hash_remove(&q->clhash, &cl->cl_common);
1139
1140         if (--cl->refcnt == 0)
1141                 hfsc_destroy_class(sch, cl);
1142
1143         sch_tree_unlock(sch);
1144         return 0;
1145 }
1146
1147 static struct hfsc_class *
1148 hfsc_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr)
1149 {
1150         struct hfsc_sched *q = qdisc_priv(sch);
1151         struct hfsc_class *cl;
1152         struct tcf_result res;
1153         struct tcf_proto *tcf;
1154         int result;
1155
1156         if (TC_H_MAJ(skb->priority ^ sch->handle) == 0 &&
1157             (cl = hfsc_find_class(skb->priority, sch)) != NULL)
1158                 if (cl->level == 0)
1159                         return cl;
1160
1161         *qerr = NET_XMIT_BYPASS;
1162         tcf = q->root.filter_list;
1163         while (tcf && (result = tc_classify(skb, tcf, &res)) >= 0) {
1164 #ifdef CONFIG_NET_CLS_ACT
1165                 switch (result) {
1166                 case TC_ACT_QUEUED:
1167                 case TC_ACT_STOLEN:
1168                         *qerr = NET_XMIT_SUCCESS;
1169                 case TC_ACT_SHOT:
1170                         return NULL;
1171                 }
1172 #endif
1173                 if ((cl = (struct hfsc_class *)res.class) == NULL) {
1174                         if ((cl = hfsc_find_class(res.classid, sch)) == NULL)
1175                                 break; /* filter selected invalid classid */
1176                 }
1177
1178                 if (cl->level == 0)
1179                         return cl; /* hit leaf class */
1180
1181                 /* apply inner filter chain */
1182                 tcf = cl->filter_list;
1183         }
1184
1185         /* classification failed, try default class */
1186         cl = hfsc_find_class(TC_H_MAKE(TC_H_MAJ(sch->handle), q->defcls), sch);
1187         if (cl == NULL || cl->level > 0)
1188                 return NULL;
1189
1190         return cl;
1191 }
1192
1193 static int
1194 hfsc_graft_class(struct Qdisc *sch, unsigned long arg, struct Qdisc *new,
1195                  struct Qdisc **old)
1196 {
1197         struct hfsc_class *cl = (struct hfsc_class *)arg;
1198
1199         if (cl == NULL)
1200                 return -ENOENT;
1201         if (cl->level > 0)
1202                 return -EINVAL;
1203         if (new == NULL) {
1204                 new = qdisc_create_dflt(sch->dev, &pfifo_qdisc_ops,
1205                                         cl->cl_common.classid);
1206                 if (new == NULL)
1207                         new = &noop_qdisc;
1208         }
1209
1210         sch_tree_lock(sch);
1211         hfsc_purge_queue(sch, cl);
1212         *old = xchg(&cl->qdisc, new);
1213         sch_tree_unlock(sch);
1214         return 0;
1215 }
1216
1217 static struct Qdisc *
1218 hfsc_class_leaf(struct Qdisc *sch, unsigned long arg)
1219 {
1220         struct hfsc_class *cl = (struct hfsc_class *)arg;
1221
1222         if (cl != NULL && cl->level == 0)
1223                 return cl->qdisc;
1224
1225         return NULL;
1226 }
1227
1228 static void
1229 hfsc_qlen_notify(struct Qdisc *sch, unsigned long arg)
1230 {
1231         struct hfsc_class *cl = (struct hfsc_class *)arg;
1232
1233         if (cl->qdisc->q.qlen == 0) {
1234                 update_vf(cl, 0, 0);
1235                 set_passive(cl);
1236         }
1237 }
1238
1239 static unsigned long
1240 hfsc_get_class(struct Qdisc *sch, u32 classid)
1241 {
1242         struct hfsc_class *cl = hfsc_find_class(classid, sch);
1243
1244         if (cl != NULL)
1245                 cl->refcnt++;
1246
1247         return (unsigned long)cl;
1248 }
1249
1250 static void
1251 hfsc_put_class(struct Qdisc *sch, unsigned long arg)
1252 {
1253         struct hfsc_class *cl = (struct hfsc_class *)arg;
1254
1255         if (--cl->refcnt == 0)
1256                 hfsc_destroy_class(sch, cl);
1257 }
1258
1259 static unsigned long
1260 hfsc_bind_tcf(struct Qdisc *sch, unsigned long parent, u32 classid)
1261 {
1262         struct hfsc_class *p = (struct hfsc_class *)parent;
1263         struct hfsc_class *cl = hfsc_find_class(classid, sch);
1264
1265         if (cl != NULL) {
1266                 if (p != NULL && p->level <= cl->level)
1267                         return 0;
1268                 cl->filter_cnt++;
1269         }
1270
1271         return (unsigned long)cl;
1272 }
1273
1274 static void
1275 hfsc_unbind_tcf(struct Qdisc *sch, unsigned long arg)
1276 {
1277         struct hfsc_class *cl = (struct hfsc_class *)arg;
1278
1279         cl->filter_cnt--;
1280 }
1281
1282 static struct tcf_proto **
1283 hfsc_tcf_chain(struct Qdisc *sch, unsigned long arg)
1284 {
1285         struct hfsc_sched *q = qdisc_priv(sch);
1286         struct hfsc_class *cl = (struct hfsc_class *)arg;
1287
1288         if (cl == NULL)
1289                 cl = &q->root;
1290
1291         return &cl->filter_list;
1292 }
1293
1294 static int
1295 hfsc_dump_sc(struct sk_buff *skb, int attr, struct internal_sc *sc)
1296 {
1297         struct tc_service_curve tsc;
1298
1299         tsc.m1 = sm2m(sc->sm1);
1300         tsc.d  = dx2d(sc->dx);
1301         tsc.m2 = sm2m(sc->sm2);
1302         NLA_PUT(skb, attr, sizeof(tsc), &tsc);
1303
1304         return skb->len;
1305
1306  nla_put_failure:
1307         return -1;
1308 }
1309
1310 static inline int
1311 hfsc_dump_curves(struct sk_buff *skb, struct hfsc_class *cl)
1312 {
1313         if ((cl->cl_flags & HFSC_RSC) &&
1314             (hfsc_dump_sc(skb, TCA_HFSC_RSC, &cl->cl_rsc) < 0))
1315                 goto nla_put_failure;
1316
1317         if ((cl->cl_flags & HFSC_FSC) &&
1318             (hfsc_dump_sc(skb, TCA_HFSC_FSC, &cl->cl_fsc) < 0))
1319                 goto nla_put_failure;
1320
1321         if ((cl->cl_flags & HFSC_USC) &&
1322             (hfsc_dump_sc(skb, TCA_HFSC_USC, &cl->cl_usc) < 0))
1323                 goto nla_put_failure;
1324
1325         return skb->len;
1326
1327  nla_put_failure:
1328         return -1;
1329 }
1330
1331 static int
1332 hfsc_dump_class(struct Qdisc *sch, unsigned long arg, struct sk_buff *skb,
1333                 struct tcmsg *tcm)
1334 {
1335         struct hfsc_class *cl = (struct hfsc_class *)arg;
1336         struct nlattr *nest;
1337
1338         tcm->tcm_parent = cl->cl_parent ? cl->cl_parent->cl_common.classid :
1339                                           TC_H_ROOT;
1340         tcm->tcm_handle = cl->cl_common.classid;
1341         if (cl->level == 0)
1342                 tcm->tcm_info = cl->qdisc->handle;
1343
1344         nest = nla_nest_start(skb, TCA_OPTIONS);
1345         if (nest == NULL)
1346                 goto nla_put_failure;
1347         if (hfsc_dump_curves(skb, cl) < 0)
1348                 goto nla_put_failure;
1349         nla_nest_end(skb, nest);
1350         return skb->len;
1351
1352  nla_put_failure:
1353         nla_nest_cancel(skb, nest);
1354         return -EMSGSIZE;
1355 }
1356
1357 static int
1358 hfsc_dump_class_stats(struct Qdisc *sch, unsigned long arg,
1359         struct gnet_dump *d)
1360 {
1361         struct hfsc_class *cl = (struct hfsc_class *)arg;
1362         struct tc_hfsc_stats xstats;
1363
1364         cl->qstats.qlen = cl->qdisc->q.qlen;
1365         xstats.level   = cl->level;
1366         xstats.period  = cl->cl_vtperiod;
1367         xstats.work    = cl->cl_total;
1368         xstats.rtwork  = cl->cl_cumul;
1369
1370         if (gnet_stats_copy_basic(d, &cl->bstats) < 0 ||
1371             gnet_stats_copy_rate_est(d, &cl->rate_est) < 0 ||
1372             gnet_stats_copy_queue(d, &cl->qstats) < 0)
1373                 return -1;
1374
1375         return gnet_stats_copy_app(d, &xstats, sizeof(xstats));
1376 }
1377
1378
1379
1380 static void
1381 hfsc_walk(struct Qdisc *sch, struct qdisc_walker *arg)
1382 {
1383         struct hfsc_sched *q = qdisc_priv(sch);
1384         struct hlist_node *n;
1385         struct hfsc_class *cl;
1386         unsigned int i;
1387
1388         if (arg->stop)
1389                 return;
1390
1391         for (i = 0; i < q->clhash.hashsize; i++) {
1392                 hlist_for_each_entry(cl, n, &q->clhash.hash[i],
1393                                      cl_common.hnode) {
1394                         if (arg->count < arg->skip) {
1395                                 arg->count++;
1396                                 continue;
1397                         }
1398                         if (arg->fn(sch, (unsigned long)cl, arg) < 0) {
1399                                 arg->stop = 1;
1400                                 return;
1401                         }
1402                         arg->count++;
1403                 }
1404         }
1405 }
1406
1407 static void
1408 hfsc_schedule_watchdog(struct Qdisc *sch)
1409 {
1410         struct hfsc_sched *q = qdisc_priv(sch);
1411         struct hfsc_class *cl;
1412         u64 next_time = 0;
1413
1414         if ((cl = eltree_get_minel(q)) != NULL)
1415                 next_time = cl->cl_e;
1416         if (q->root.cl_cfmin != 0) {
1417                 if (next_time == 0 || next_time > q->root.cl_cfmin)
1418                         next_time = q->root.cl_cfmin;
1419         }
1420         WARN_ON(next_time == 0);
1421         qdisc_watchdog_schedule(&q->watchdog, next_time);
1422 }
1423
1424 static int
1425 hfsc_init_qdisc(struct Qdisc *sch, struct nlattr *opt)
1426 {
1427         struct hfsc_sched *q = qdisc_priv(sch);
1428         struct tc_hfsc_qopt *qopt;
1429         int err;
1430
1431         if (opt == NULL || nla_len(opt) < sizeof(*qopt))
1432                 return -EINVAL;
1433         qopt = nla_data(opt);
1434
1435         q->defcls = qopt->defcls;
1436         err = qdisc_class_hash_init(&q->clhash);
1437         if (err < 0)
1438                 return err;
1439         q->eligible = RB_ROOT;
1440         INIT_LIST_HEAD(&q->droplist);
1441         skb_queue_head_init(&q->requeue);
1442
1443         q->root.cl_common.classid = sch->handle;
1444         q->root.refcnt  = 1;
1445         q->root.sched   = q;
1446         q->root.qdisc = qdisc_create_dflt(sch->dev, &pfifo_qdisc_ops,
1447                                           sch->handle);
1448         if (q->root.qdisc == NULL)
1449                 q->root.qdisc = &noop_qdisc;
1450         INIT_LIST_HEAD(&q->root.children);
1451         q->root.vt_tree = RB_ROOT;
1452         q->root.cf_tree = RB_ROOT;
1453
1454         qdisc_class_hash_insert(&q->clhash, &q->root.cl_common);
1455         qdisc_class_hash_grow(sch, &q->clhash);
1456
1457         qdisc_watchdog_init(&q->watchdog, sch);
1458
1459         return 0;
1460 }
1461
1462 static int
1463 hfsc_change_qdisc(struct Qdisc *sch, struct nlattr *opt)
1464 {
1465         struct hfsc_sched *q = qdisc_priv(sch);
1466         struct tc_hfsc_qopt *qopt;
1467
1468         if (opt == NULL || nla_len(opt) < sizeof(*qopt))
1469                 return -EINVAL;
1470         qopt = nla_data(opt);
1471
1472         sch_tree_lock(sch);
1473         q->defcls = qopt->defcls;
1474         sch_tree_unlock(sch);
1475
1476         return 0;
1477 }
1478
1479 static void
1480 hfsc_reset_class(struct hfsc_class *cl)
1481 {
1482         cl->cl_total        = 0;
1483         cl->cl_cumul        = 0;
1484         cl->cl_d            = 0;
1485         cl->cl_e            = 0;
1486         cl->cl_vt           = 0;
1487         cl->cl_vtadj        = 0;
1488         cl->cl_vtoff        = 0;
1489         cl->cl_cvtmin       = 0;
1490         cl->cl_cvtmax       = 0;
1491         cl->cl_cvtoff       = 0;
1492         cl->cl_pcvtoff      = 0;
1493         cl->cl_vtperiod     = 0;
1494         cl->cl_parentperiod = 0;
1495         cl->cl_f            = 0;
1496         cl->cl_myf          = 0;
1497         cl->cl_myfadj       = 0;
1498         cl->cl_cfmin        = 0;
1499         cl->cl_nactive      = 0;
1500
1501         cl->vt_tree = RB_ROOT;
1502         cl->cf_tree = RB_ROOT;
1503         qdisc_reset(cl->qdisc);
1504
1505         if (cl->cl_flags & HFSC_RSC)
1506                 rtsc_init(&cl->cl_deadline, &cl->cl_rsc, 0, 0);
1507         if (cl->cl_flags & HFSC_FSC)
1508                 rtsc_init(&cl->cl_virtual, &cl->cl_fsc, 0, 0);
1509         if (cl->cl_flags & HFSC_USC)
1510                 rtsc_init(&cl->cl_ulimit, &cl->cl_usc, 0, 0);
1511 }
1512
1513 static void
1514 hfsc_reset_qdisc(struct Qdisc *sch)
1515 {
1516         struct hfsc_sched *q = qdisc_priv(sch);
1517         struct hfsc_class *cl;
1518         struct hlist_node *n;
1519         unsigned int i;
1520
1521         for (i = 0; i < q->clhash.hashsize; i++) {
1522                 hlist_for_each_entry(cl, n, &q->clhash.hash[i], cl_common.hnode)
1523                         hfsc_reset_class(cl);
1524         }
1525         __skb_queue_purge(&q->requeue);
1526         q->eligible = RB_ROOT;
1527         INIT_LIST_HEAD(&q->droplist);
1528         qdisc_watchdog_cancel(&q->watchdog);
1529         sch->q.qlen = 0;
1530 }
1531
1532 static void
1533 hfsc_destroy_qdisc(struct Qdisc *sch)
1534 {
1535         struct hfsc_sched *q = qdisc_priv(sch);
1536         struct hlist_node *n, *next;
1537         struct hfsc_class *cl;
1538         unsigned int i;
1539
1540         for (i = 0; i < q->clhash.hashsize; i++) {
1541                 hlist_for_each_entry(cl, n, &q->clhash.hash[i], cl_common.hnode)
1542                         tcf_destroy_chain(&cl->filter_list);
1543         }
1544         for (i = 0; i < q->clhash.hashsize; i++) {
1545                 hlist_for_each_entry_safe(cl, n, next, &q->clhash.hash[i],
1546                                           cl_common.hnode)
1547                         hfsc_destroy_class(sch, cl);
1548         }
1549         qdisc_class_hash_destroy(&q->clhash);
1550         __skb_queue_purge(&q->requeue);
1551         qdisc_watchdog_cancel(&q->watchdog);
1552 }
1553
1554 static int
1555 hfsc_dump_qdisc(struct Qdisc *sch, struct sk_buff *skb)
1556 {
1557         struct hfsc_sched *q = qdisc_priv(sch);
1558         unsigned char *b = skb_tail_pointer(skb);
1559         struct tc_hfsc_qopt qopt;
1560
1561         qopt.defcls = q->defcls;
1562         NLA_PUT(skb, TCA_OPTIONS, sizeof(qopt), &qopt);
1563         return skb->len;
1564
1565  nla_put_failure:
1566         nlmsg_trim(skb, b);
1567         return -1;
1568 }
1569
1570 static int
1571 hfsc_enqueue(struct sk_buff *skb, struct Qdisc *sch)
1572 {
1573         struct hfsc_class *cl;
1574         unsigned int len;
1575         int err;
1576
1577         cl = hfsc_classify(skb, sch, &err);
1578         if (cl == NULL) {
1579                 if (err == NET_XMIT_BYPASS)
1580                         sch->qstats.drops++;
1581                 kfree_skb(skb);
1582                 return err;
1583         }
1584
1585         len = skb->len;
1586         err = cl->qdisc->enqueue(skb, cl->qdisc);
1587         if (unlikely(err != NET_XMIT_SUCCESS)) {
1588                 cl->qstats.drops++;
1589                 sch->qstats.drops++;
1590                 return err;
1591         }
1592
1593         if (cl->qdisc->q.qlen == 1)
1594                 set_active(cl, len);
1595
1596         cl->bstats.packets++;
1597         cl->bstats.bytes += len;
1598         sch->bstats.packets++;
1599         sch->bstats.bytes += len;
1600         sch->q.qlen++;
1601
1602         return NET_XMIT_SUCCESS;
1603 }
1604
1605 static struct sk_buff *
1606 hfsc_dequeue(struct Qdisc *sch)
1607 {
1608         struct hfsc_sched *q = qdisc_priv(sch);
1609         struct hfsc_class *cl;
1610         struct sk_buff *skb;
1611         u64 cur_time;
1612         unsigned int next_len;
1613         int realtime = 0;
1614
1615         if (sch->q.qlen == 0)
1616                 return NULL;
1617         if ((skb = __skb_dequeue(&q->requeue)))
1618                 goto out;
1619
1620         cur_time = psched_get_time();
1621
1622         /*
1623          * if there are eligible classes, use real-time criteria.
1624          * find the class with the minimum deadline among
1625          * the eligible classes.
1626          */
1627         if ((cl = eltree_get_mindl(q, cur_time)) != NULL) {
1628                 realtime = 1;
1629         } else {
1630                 /*
1631                  * use link-sharing criteria
1632                  * get the class with the minimum vt in the hierarchy
1633                  */
1634                 cl = vttree_get_minvt(&q->root, cur_time);
1635                 if (cl == NULL) {
1636                         sch->qstats.overlimits++;
1637                         hfsc_schedule_watchdog(sch);
1638                         return NULL;
1639                 }
1640         }
1641
1642         skb = cl->qdisc->dequeue(cl->qdisc);
1643         if (skb == NULL) {
1644                 if (net_ratelimit())
1645                         printk("HFSC: Non-work-conserving qdisc ?\n");
1646                 return NULL;
1647         }
1648
1649         update_vf(cl, skb->len, cur_time);
1650         if (realtime)
1651                 cl->cl_cumul += skb->len;
1652
1653         if (cl->qdisc->q.qlen != 0) {
1654                 if (cl->cl_flags & HFSC_RSC) {
1655                         /* update ed */
1656                         next_len = qdisc_peek_len(cl->qdisc);
1657                         if (realtime)
1658                                 update_ed(cl, next_len);
1659                         else
1660                                 update_d(cl, next_len);
1661                 }
1662         } else {
1663                 /* the class becomes passive */
1664                 set_passive(cl);
1665         }
1666
1667  out:
1668         sch->flags &= ~TCQ_F_THROTTLED;
1669         sch->q.qlen--;
1670
1671         return skb;
1672 }
1673
1674 static int
1675 hfsc_requeue(struct sk_buff *skb, struct Qdisc *sch)
1676 {
1677         struct hfsc_sched *q = qdisc_priv(sch);
1678
1679         __skb_queue_head(&q->requeue, skb);
1680         sch->q.qlen++;
1681         sch->qstats.requeues++;
1682         return NET_XMIT_SUCCESS;
1683 }
1684
1685 static unsigned int
1686 hfsc_drop(struct Qdisc *sch)
1687 {
1688         struct hfsc_sched *q = qdisc_priv(sch);
1689         struct hfsc_class *cl;
1690         unsigned int len;
1691
1692         list_for_each_entry(cl, &q->droplist, dlist) {
1693                 if (cl->qdisc->ops->drop != NULL &&
1694                     (len = cl->qdisc->ops->drop(cl->qdisc)) > 0) {
1695                         if (cl->qdisc->q.qlen == 0) {
1696                                 update_vf(cl, 0, 0);
1697                                 set_passive(cl);
1698                         } else {
1699                                 list_move_tail(&cl->dlist, &q->droplist);
1700                         }
1701                         cl->qstats.drops++;
1702                         sch->qstats.drops++;
1703                         sch->q.qlen--;
1704                         return len;
1705                 }
1706         }
1707         return 0;
1708 }
1709
1710 static const struct Qdisc_class_ops hfsc_class_ops = {
1711         .change         = hfsc_change_class,
1712         .delete         = hfsc_delete_class,
1713         .graft          = hfsc_graft_class,
1714         .leaf           = hfsc_class_leaf,
1715         .qlen_notify    = hfsc_qlen_notify,
1716         .get            = hfsc_get_class,
1717         .put            = hfsc_put_class,
1718         .bind_tcf       = hfsc_bind_tcf,
1719         .unbind_tcf     = hfsc_unbind_tcf,
1720         .tcf_chain      = hfsc_tcf_chain,
1721         .dump           = hfsc_dump_class,
1722         .dump_stats     = hfsc_dump_class_stats,
1723         .walk           = hfsc_walk
1724 };
1725
1726 static struct Qdisc_ops hfsc_qdisc_ops __read_mostly = {
1727         .id             = "hfsc",
1728         .init           = hfsc_init_qdisc,
1729         .change         = hfsc_change_qdisc,
1730         .reset          = hfsc_reset_qdisc,
1731         .destroy        = hfsc_destroy_qdisc,
1732         .dump           = hfsc_dump_qdisc,
1733         .enqueue        = hfsc_enqueue,
1734         .dequeue        = hfsc_dequeue,
1735         .requeue        = hfsc_requeue,
1736         .drop           = hfsc_drop,
1737         .cl_ops         = &hfsc_class_ops,
1738         .priv_size      = sizeof(struct hfsc_sched),
1739         .owner          = THIS_MODULE
1740 };
1741
1742 static int __init
1743 hfsc_init(void)
1744 {
1745         return register_qdisc(&hfsc_qdisc_ops);
1746 }
1747
1748 static void __exit
1749 hfsc_cleanup(void)
1750 {
1751         unregister_qdisc(&hfsc_qdisc_ops);
1752 }
1753
1754 MODULE_LICENSE("GPL");
1755 module_init(hfsc_init);
1756 module_exit(hfsc_cleanup);