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 84 struct 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 */ 94 struct 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 }; 104 105 enum hfsc_class_flags { 106 HFSC_RSC = 0x1, 107 HFSC_FSC = 0x2, 108 HFSC_USC = 0x4 109 }; 110 111 struct hfsc_class { 112 struct Qdisc_class_common cl_common; 113 114 struct gnet_stats_basic_sync 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 level; /* class level in hierarchy */ 120 121 struct hfsc_sched *sched; /* scheduler data */ 122 struct hfsc_class *cl_parent; /* parent class */ 123 struct list_head siblings; /* sibling classes */ 124 struct list_head children; /* child classes */ 125 struct Qdisc *qdisc; /* leaf qdisc */ 126 127 struct rb_node el_node; /* qdisc's eligible tree member */ 128 struct rb_root vt_tree; /* active children sorted by cl_vt */ 129 struct rb_node vt_node; /* parent's vt_tree member */ 130 struct rb_root cf_tree; /* active children sorted by cl_f */ 131 struct rb_node cf_node; /* parent's cf_heap member */ 132 133 u64 cl_total; /* total work in bytes */ 134 u64 cl_cumul; /* cumulative work in bytes done by 135 real-time criteria */ 136 137 u64 cl_d; /* deadline*/ 138 u64 cl_e; /* eligible time */ 139 u64 cl_vt; /* virtual time */ 140 u64 cl_f; /* time when this class will fit for 141 link-sharing, max(myf, cfmin) */ 142 u64 cl_myf; /* my fit-time (calculated from this 143 class's own upperlimit curve) */ 144 u64 cl_cfmin; /* earliest children's fit-time (used 145 with cl_myf to obtain cl_f) */ 146 u64 cl_cvtmin; /* minimal virtual time among the 147 children fit for link-sharing 148 (monotonic within a period) */ 149 u64 cl_vtadj; /* intra-period cumulative vt 150 adjustment */ 151 u64 cl_cvtoff; /* largest virtual time seen among 152 the children */ 153 154 struct internal_sc cl_rsc; /* internal real-time service curve */ 155 struct internal_sc cl_fsc; /* internal fair service curve */ 156 struct internal_sc cl_usc; /* internal upperlimit service curve */ 157 struct runtime_sc cl_deadline; /* deadline curve */ 158 struct runtime_sc cl_eligible; /* eligible curve */ 159 struct runtime_sc cl_virtual; /* virtual curve */ 160 struct runtime_sc cl_ulimit; /* upperlimit curve */ 161 162 u8 cl_flags; /* which curves are valid */ 163 u32 cl_vtperiod; /* vt period sequence number */ 164 u32 cl_parentperiod;/* parent's vt period sequence number*/ 165 u32 cl_nactive; /* number of active children */ 166 }; 167 168 struct hfsc_sched { 169 u16 defcls; /* default class id */ 170 struct hfsc_class root; /* root class */ 171 struct Qdisc_class_hash clhash; /* class hash */ 172 struct rb_root eligible; /* eligible tree */ 173 struct qdisc_watchdog watchdog; /* watchdog timer */ 174 }; 175 176 #define HT_INFINITY 0xffffffffffffffffULL /* infinite time value */ 177 178 static bool cl_in_el_or_vttree(struct hfsc_class *cl) 179 { 180 return ((cl->cl_flags & HFSC_FSC) && cl->cl_nactive) || 181 ((cl->cl_flags & HFSC_RSC) && !RB_EMPTY_NODE(&cl->el_node)); 182 } 183 184 /* 185 * eligible tree holds backlogged classes being sorted by their eligible times. 186 * there is one eligible tree per hfsc instance. 187 */ 188 189 static void 190 eltree_insert(struct hfsc_class *cl) 191 { 192 struct rb_node **p = &cl->sched->eligible.rb_node; 193 struct rb_node *parent = NULL; 194 struct hfsc_class *cl1; 195 196 while (*p != NULL) { 197 parent = *p; 198 cl1 = rb_entry(parent, struct hfsc_class, el_node); 199 if (cl->cl_e >= cl1->cl_e) 200 p = &parent->rb_right; 201 else 202 p = &parent->rb_left; 203 } 204 rb_link_node(&cl->el_node, parent, p); 205 rb_insert_color(&cl->el_node, &cl->sched->eligible); 206 } 207 208 static inline void 209 eltree_remove(struct hfsc_class *cl) 210 { 211 if (!RB_EMPTY_NODE(&cl->el_node)) { 212 rb_erase(&cl->el_node, &cl->sched->eligible); 213 RB_CLEAR_NODE(&cl->el_node); 214 } 215 } 216 217 static inline void 218 eltree_update(struct hfsc_class *cl) 219 { 220 eltree_remove(cl); 221 eltree_insert(cl); 222 } 223 224 /* find the class with the minimum deadline among the eligible classes */ 225 static inline struct hfsc_class * 226 eltree_get_mindl(struct hfsc_sched *q, u64 cur_time) 227 { 228 struct hfsc_class *p, *cl = NULL; 229 struct rb_node *n; 230 231 for (n = rb_first(&q->eligible); n != NULL; n = rb_next(n)) { 232 p = rb_entry(n, struct hfsc_class, el_node); 233 if (p->cl_e > cur_time) 234 break; 235 if (cl == NULL || p->cl_d < cl->cl_d) 236 cl = p; 237 } 238 return cl; 239 } 240 241 /* find the class with minimum eligible time among the eligible classes */ 242 static inline struct hfsc_class * 243 eltree_get_minel(struct hfsc_sched *q) 244 { 245 struct rb_node *n; 246 247 n = rb_first(&q->eligible); 248 if (n == NULL) 249 return NULL; 250 return rb_entry(n, struct hfsc_class, el_node); 251 } 252 253 /* 254 * vttree holds holds backlogged child classes being sorted by their virtual 255 * time. each intermediate class has one vttree. 256 */ 257 static void 258 vttree_insert(struct hfsc_class *cl) 259 { 260 struct rb_node **p = &cl->cl_parent->vt_tree.rb_node; 261 struct rb_node *parent = NULL; 262 struct hfsc_class *cl1; 263 264 while (*p != NULL) { 265 parent = *p; 266 cl1 = rb_entry(parent, struct hfsc_class, vt_node); 267 if (cl->cl_vt >= cl1->cl_vt) 268 p = &parent->rb_right; 269 else 270 p = &parent->rb_left; 271 } 272 rb_link_node(&cl->vt_node, parent, p); 273 rb_insert_color(&cl->vt_node, &cl->cl_parent->vt_tree); 274 } 275 276 static inline void 277 vttree_remove(struct hfsc_class *cl) 278 { 279 rb_erase(&cl->vt_node, &cl->cl_parent->vt_tree); 280 } 281 282 static inline void 283 vttree_update(struct hfsc_class *cl) 284 { 285 vttree_remove(cl); 286 vttree_insert(cl); 287 } 288 289 static inline struct hfsc_class * 290 vttree_firstfit(struct hfsc_class *cl, u64 cur_time) 291 { 292 struct hfsc_class *p; 293 struct rb_node *n; 294 295 for (n = rb_first(&cl->vt_tree); n != NULL; n = rb_next(n)) { 296 p = rb_entry(n, struct hfsc_class, vt_node); 297 if (p->cl_f <= cur_time) 298 return p; 299 } 300 return NULL; 301 } 302 303 /* 304 * get the leaf class with the minimum vt in the hierarchy 305 */ 306 static struct hfsc_class * 307 vttree_get_minvt(struct hfsc_class *cl, u64 cur_time) 308 { 309 /* if root-class's cfmin is bigger than cur_time nothing to do */ 310 if (cl->cl_cfmin > cur_time) 311 return NULL; 312 313 while (cl->level > 0) { 314 cl = vttree_firstfit(cl, cur_time); 315 if (cl == NULL) 316 return NULL; 317 /* 318 * update parent's cl_cvtmin. 319 */ 320 if (cl->cl_parent->cl_cvtmin < cl->cl_vt) 321 cl->cl_parent->cl_cvtmin = cl->cl_vt; 322 } 323 return cl; 324 } 325 326 static void 327 cftree_insert(struct hfsc_class *cl) 328 { 329 struct rb_node **p = &cl->cl_parent->cf_tree.rb_node; 330 struct rb_node *parent = NULL; 331 struct hfsc_class *cl1; 332 333 while (*p != NULL) { 334 parent = *p; 335 cl1 = rb_entry(parent, struct hfsc_class, cf_node); 336 if (cl->cl_f >= cl1->cl_f) 337 p = &parent->rb_right; 338 else 339 p = &parent->rb_left; 340 } 341 rb_link_node(&cl->cf_node, parent, p); 342 rb_insert_color(&cl->cf_node, &cl->cl_parent->cf_tree); 343 } 344 345 static inline void 346 cftree_remove(struct hfsc_class *cl) 347 { 348 rb_erase(&cl->cf_node, &cl->cl_parent->cf_tree); 349 } 350 351 static inline void 352 cftree_update(struct hfsc_class *cl) 353 { 354 cftree_remove(cl); 355 cftree_insert(cl); 356 } 357 358 /* 359 * service curve support functions 360 * 361 * external service curve parameters 362 * m: bps 363 * d: us 364 * internal service curve parameters 365 * sm: (bytes/psched_us) << SM_SHIFT 366 * ism: (psched_us/byte) << ISM_SHIFT 367 * dx: psched_us 368 * 369 * The clock source resolution with ktime and PSCHED_SHIFT 10 is 1.024us. 370 * 371 * sm and ism are scaled in order to keep effective digits. 372 * SM_SHIFT and ISM_SHIFT are selected to keep at least 4 effective 373 * digits in decimal using the following table. 374 * 375 * bits/sec 100Kbps 1Mbps 10Mbps 100Mbps 1Gbps 376 * ------------+------------------------------------------------------- 377 * bytes/1.024us 12.8e-3 128e-3 1280e-3 12800e-3 128000e-3 378 * 379 * 1.024us/byte 78.125 7.8125 0.78125 0.078125 0.0078125 380 * 381 * So, for PSCHED_SHIFT 10 we need: SM_SHIFT 20, ISM_SHIFT 18. 382 */ 383 #define SM_SHIFT (30 - PSCHED_SHIFT) 384 #define ISM_SHIFT (8 + PSCHED_SHIFT) 385 386 #define SM_MASK ((1ULL << SM_SHIFT) - 1) 387 #define ISM_MASK ((1ULL << ISM_SHIFT) - 1) 388 389 static inline u64 390 seg_x2y(u64 x, u64 sm) 391 { 392 u64 y; 393 394 /* 395 * compute 396 * y = x * sm >> SM_SHIFT 397 * but divide it for the upper and lower bits to avoid overflow 398 */ 399 y = (x >> SM_SHIFT) * sm + (((x & SM_MASK) * sm) >> SM_SHIFT); 400 return y; 401 } 402 403 static inline u64 404 seg_y2x(u64 y, u64 ism) 405 { 406 u64 x; 407 408 if (y == 0) 409 x = 0; 410 else if (ism == HT_INFINITY) 411 x = HT_INFINITY; 412 else { 413 x = (y >> ISM_SHIFT) * ism 414 + (((y & ISM_MASK) * ism) >> ISM_SHIFT); 415 } 416 return x; 417 } 418 419 /* Convert m (bps) into sm (bytes/psched us) */ 420 static u64 421 m2sm(u32 m) 422 { 423 u64 sm; 424 425 sm = ((u64)m << SM_SHIFT); 426 sm += PSCHED_TICKS_PER_SEC - 1; 427 do_div(sm, PSCHED_TICKS_PER_SEC); 428 return sm; 429 } 430 431 /* convert m (bps) into ism (psched us/byte) */ 432 static u64 433 m2ism(u32 m) 434 { 435 u64 ism; 436 437 if (m == 0) 438 ism = HT_INFINITY; 439 else { 440 ism = ((u64)PSCHED_TICKS_PER_SEC << ISM_SHIFT); 441 ism += m - 1; 442 do_div(ism, m); 443 } 444 return ism; 445 } 446 447 /* convert d (us) into dx (psched us) */ 448 static u64 449 d2dx(u32 d) 450 { 451 u64 dx; 452 453 dx = ((u64)d * PSCHED_TICKS_PER_SEC); 454 dx += USEC_PER_SEC - 1; 455 do_div(dx, USEC_PER_SEC); 456 return dx; 457 } 458 459 /* convert sm (bytes/psched us) into m (bps) */ 460 static u32 461 sm2m(u64 sm) 462 { 463 u64 m; 464 465 m = (sm * PSCHED_TICKS_PER_SEC) >> SM_SHIFT; 466 return (u32)m; 467 } 468 469 /* convert dx (psched us) into d (us) */ 470 static u32 471 dx2d(u64 dx) 472 { 473 u64 d; 474 475 d = dx * USEC_PER_SEC; 476 do_div(d, PSCHED_TICKS_PER_SEC); 477 return (u32)d; 478 } 479 480 static void 481 sc2isc(struct tc_service_curve *sc, struct internal_sc *isc) 482 { 483 isc->sm1 = m2sm(sc->m1); 484 isc->ism1 = m2ism(sc->m1); 485 isc->dx = d2dx(sc->d); 486 isc->dy = seg_x2y(isc->dx, isc->sm1); 487 isc->sm2 = m2sm(sc->m2); 488 isc->ism2 = m2ism(sc->m2); 489 } 490 491 /* 492 * initialize the runtime service curve with the given internal 493 * service curve starting at (x, y). 494 */ 495 static void 496 rtsc_init(struct runtime_sc *rtsc, struct internal_sc *isc, u64 x, u64 y) 497 { 498 rtsc->x = x; 499 rtsc->y = y; 500 rtsc->sm1 = isc->sm1; 501 rtsc->ism1 = isc->ism1; 502 rtsc->dx = isc->dx; 503 rtsc->dy = isc->dy; 504 rtsc->sm2 = isc->sm2; 505 rtsc->ism2 = isc->ism2; 506 } 507 508 /* 509 * calculate the y-projection of the runtime service curve by the 510 * given x-projection value 511 */ 512 static u64 513 rtsc_y2x(struct runtime_sc *rtsc, u64 y) 514 { 515 u64 x; 516 517 if (y < rtsc->y) 518 x = rtsc->x; 519 else if (y <= rtsc->y + rtsc->dy) { 520 /* x belongs to the 1st segment */ 521 if (rtsc->dy == 0) 522 x = rtsc->x + rtsc->dx; 523 else 524 x = rtsc->x + seg_y2x(y - rtsc->y, rtsc->ism1); 525 } else { 526 /* x belongs to the 2nd segment */ 527 x = rtsc->x + rtsc->dx 528 + seg_y2x(y - rtsc->y - rtsc->dy, rtsc->ism2); 529 } 530 return x; 531 } 532 533 static u64 534 rtsc_x2y(struct runtime_sc *rtsc, u64 x) 535 { 536 u64 y; 537 538 if (x <= rtsc->x) 539 y = rtsc->y; 540 else if (x <= rtsc->x + rtsc->dx) 541 /* y belongs to the 1st segment */ 542 y = rtsc->y + seg_x2y(x - rtsc->x, rtsc->sm1); 543 else 544 /* y belongs to the 2nd segment */ 545 y = rtsc->y + rtsc->dy 546 + seg_x2y(x - rtsc->x - rtsc->dx, rtsc->sm2); 547 return y; 548 } 549 550 /* 551 * update the runtime service curve by taking the minimum of the current 552 * runtime service curve and the service curve starting at (x, y). 553 */ 554 static void 555 rtsc_min(struct runtime_sc *rtsc, struct internal_sc *isc, u64 x, u64 y) 556 { 557 u64 y1, y2, dx, dy; 558 u32 dsm; 559 560 if (isc->sm1 <= isc->sm2) { 561 /* service curve is convex */ 562 y1 = rtsc_x2y(rtsc, x); 563 if (y1 < y) 564 /* the current rtsc is smaller */ 565 return; 566 rtsc->x = x; 567 rtsc->y = y; 568 return; 569 } 570 571 /* 572 * service curve is concave 573 * compute the two y values of the current rtsc 574 * y1: at x 575 * y2: at (x + dx) 576 */ 577 y1 = rtsc_x2y(rtsc, x); 578 if (y1 <= y) { 579 /* rtsc is below isc, no change to rtsc */ 580 return; 581 } 582 583 y2 = rtsc_x2y(rtsc, x + isc->dx); 584 if (y2 >= y + isc->dy) { 585 /* rtsc is above isc, replace rtsc by isc */ 586 rtsc->x = x; 587 rtsc->y = y; 588 rtsc->dx = isc->dx; 589 rtsc->dy = isc->dy; 590 return; 591 } 592 593 /* 594 * the two curves intersect 595 * compute the offsets (dx, dy) using the reverse 596 * function of seg_x2y() 597 * seg_x2y(dx, sm1) == seg_x2y(dx, sm2) + (y1 - y) 598 */ 599 dx = (y1 - y) << SM_SHIFT; 600 dsm = isc->sm1 - isc->sm2; 601 do_div(dx, dsm); 602 /* 603 * check if (x, y1) belongs to the 1st segment of rtsc. 604 * if so, add the offset. 605 */ 606 if (rtsc->x + rtsc->dx > x) 607 dx += rtsc->x + rtsc->dx - x; 608 dy = seg_x2y(dx, isc->sm1); 609 610 rtsc->x = x; 611 rtsc->y = y; 612 rtsc->dx = dx; 613 rtsc->dy = dy; 614 } 615 616 static void 617 init_ed(struct hfsc_class *cl, unsigned int next_len) 618 { 619 u64 cur_time = psched_get_time(); 620 621 /* update the deadline curve */ 622 rtsc_min(&cl->cl_deadline, &cl->cl_rsc, cur_time, cl->cl_cumul); 623 624 /* 625 * update the eligible curve. 626 * for concave, it is equal to the deadline curve. 627 * for convex, it is a linear curve with slope m2. 628 */ 629 cl->cl_eligible = cl->cl_deadline; 630 if (cl->cl_rsc.sm1 <= cl->cl_rsc.sm2) { 631 cl->cl_eligible.dx = 0; 632 cl->cl_eligible.dy = 0; 633 } 634 635 /* compute e and d */ 636 cl->cl_e = rtsc_y2x(&cl->cl_eligible, cl->cl_cumul); 637 cl->cl_d = rtsc_y2x(&cl->cl_deadline, cl->cl_cumul + next_len); 638 639 eltree_insert(cl); 640 } 641 642 static void 643 update_ed(struct hfsc_class *cl, unsigned int next_len) 644 { 645 cl->cl_e = rtsc_y2x(&cl->cl_eligible, cl->cl_cumul); 646 cl->cl_d = rtsc_y2x(&cl->cl_deadline, cl->cl_cumul + next_len); 647 648 eltree_update(cl); 649 } 650 651 static inline void 652 update_d(struct hfsc_class *cl, unsigned int next_len) 653 { 654 cl->cl_d = rtsc_y2x(&cl->cl_deadline, cl->cl_cumul + next_len); 655 } 656 657 static inline void 658 update_cfmin(struct hfsc_class *cl) 659 { 660 struct rb_node *n = rb_first(&cl->cf_tree); 661 struct hfsc_class *p; 662 663 if (n == NULL) { 664 cl->cl_cfmin = 0; 665 return; 666 } 667 p = rb_entry(n, struct hfsc_class, cf_node); 668 cl->cl_cfmin = p->cl_f; 669 } 670 671 static void 672 init_vf(struct hfsc_class *cl, unsigned int len) 673 { 674 struct hfsc_class *max_cl; 675 struct rb_node *n; 676 u64 vt, f, cur_time; 677 int go_active; 678 679 cur_time = 0; 680 go_active = 1; 681 for (; cl->cl_parent != NULL; cl = cl->cl_parent) { 682 if (go_active && cl->cl_nactive++ == 0) 683 go_active = 1; 684 else 685 go_active = 0; 686 687 if (go_active) { 688 n = rb_last(&cl->cl_parent->vt_tree); 689 if (n != NULL) { 690 max_cl = rb_entry(n, struct hfsc_class, vt_node); 691 /* 692 * set vt to the average of the min and max 693 * classes. if the parent's period didn't 694 * change, don't decrease vt of the class. 695 */ 696 vt = max_cl->cl_vt; 697 if (cl->cl_parent->cl_cvtmin != 0) 698 vt = (cl->cl_parent->cl_cvtmin + vt)/2; 699 700 if (cl->cl_parent->cl_vtperiod != 701 cl->cl_parentperiod || vt > cl->cl_vt) 702 cl->cl_vt = vt; 703 } else { 704 /* 705 * first child for a new parent backlog period. 706 * initialize cl_vt to the highest value seen 707 * among the siblings. this is analogous to 708 * what cur_time would provide in realtime case. 709 */ 710 cl->cl_vt = cl->cl_parent->cl_cvtoff; 711 cl->cl_parent->cl_cvtmin = 0; 712 } 713 714 /* update the virtual curve */ 715 rtsc_min(&cl->cl_virtual, &cl->cl_fsc, cl->cl_vt, cl->cl_total); 716 cl->cl_vtadj = 0; 717 718 cl->cl_vtperiod++; /* increment vt period */ 719 cl->cl_parentperiod = cl->cl_parent->cl_vtperiod; 720 if (cl->cl_parent->cl_nactive == 0) 721 cl->cl_parentperiod++; 722 cl->cl_f = 0; 723 724 vttree_insert(cl); 725 cftree_insert(cl); 726 727 if (cl->cl_flags & HFSC_USC) { 728 /* class has upper limit curve */ 729 if (cur_time == 0) 730 cur_time = psched_get_time(); 731 732 /* update the ulimit curve */ 733 rtsc_min(&cl->cl_ulimit, &cl->cl_usc, cur_time, 734 cl->cl_total); 735 /* compute myf */ 736 cl->cl_myf = rtsc_y2x(&cl->cl_ulimit, 737 cl->cl_total); 738 } 739 } 740 741 f = max(cl->cl_myf, cl->cl_cfmin); 742 if (f != cl->cl_f) { 743 cl->cl_f = f; 744 cftree_update(cl); 745 } 746 update_cfmin(cl->cl_parent); 747 } 748 } 749 750 static void 751 update_vf(struct hfsc_class *cl, unsigned int len, u64 cur_time) 752 { 753 u64 f; /* , myf_bound, delta; */ 754 int go_passive = 0; 755 756 if (cl->qdisc->q.qlen == 0 && cl->cl_flags & HFSC_FSC) 757 go_passive = 1; 758 759 for (; cl->cl_parent != NULL; cl = cl->cl_parent) { 760 cl->cl_total += len; 761 762 if (!(cl->cl_flags & HFSC_FSC) || cl->cl_nactive == 0) 763 continue; 764 765 if (go_passive && --cl->cl_nactive == 0) 766 go_passive = 1; 767 else 768 go_passive = 0; 769 770 /* update vt */ 771 cl->cl_vt = rtsc_y2x(&cl->cl_virtual, cl->cl_total) + cl->cl_vtadj; 772 773 /* 774 * if vt of the class is smaller than cvtmin, 775 * the class was skipped in the past due to non-fit. 776 * if so, we need to adjust vtadj. 777 */ 778 if (cl->cl_vt < cl->cl_parent->cl_cvtmin) { 779 cl->cl_vtadj += cl->cl_parent->cl_cvtmin - cl->cl_vt; 780 cl->cl_vt = cl->cl_parent->cl_cvtmin; 781 } 782 783 if (go_passive) { 784 /* no more active child, going passive */ 785 786 /* update cvtoff of the parent class */ 787 if (cl->cl_vt > cl->cl_parent->cl_cvtoff) 788 cl->cl_parent->cl_cvtoff = cl->cl_vt; 789 790 /* remove this class from the vt tree */ 791 vttree_remove(cl); 792 793 cftree_remove(cl); 794 update_cfmin(cl->cl_parent); 795 796 continue; 797 } 798 799 /* update the vt tree */ 800 vttree_update(cl); 801 802 /* update f */ 803 if (cl->cl_flags & HFSC_USC) { 804 cl->cl_myf = rtsc_y2x(&cl->cl_ulimit, cl->cl_total); 805 #if 0 806 cl->cl_myf = cl->cl_myfadj + rtsc_y2x(&cl->cl_ulimit, 807 cl->cl_total); 808 /* 809 * This code causes classes to stay way under their 810 * limit when multiple classes are used at gigabit 811 * speed. needs investigation. -kaber 812 */ 813 /* 814 * if myf lags behind by more than one clock tick 815 * from the current time, adjust myfadj to prevent 816 * a rate-limited class from going greedy. 817 * in a steady state under rate-limiting, myf 818 * fluctuates within one clock tick. 819 */ 820 myf_bound = cur_time - PSCHED_JIFFIE2US(1); 821 if (cl->cl_myf < myf_bound) { 822 delta = cur_time - cl->cl_myf; 823 cl->cl_myfadj += delta; 824 cl->cl_myf += delta; 825 } 826 #endif 827 } 828 829 f = max(cl->cl_myf, cl->cl_cfmin); 830 if (f != cl->cl_f) { 831 cl->cl_f = f; 832 cftree_update(cl); 833 update_cfmin(cl->cl_parent); 834 } 835 } 836 } 837 838 static unsigned int 839 qdisc_peek_len(struct Qdisc *sch) 840 { 841 struct sk_buff *skb; 842 unsigned int len; 843 844 skb = sch->ops->peek(sch); 845 if (unlikely(skb == NULL)) { 846 qdisc_warn_nonwc("qdisc_peek_len", sch); 847 return 0; 848 } 849 len = qdisc_pkt_len(skb); 850 851 return len; 852 } 853 854 static void 855 hfsc_adjust_levels(struct hfsc_class *cl) 856 { 857 struct hfsc_class *p; 858 unsigned int level; 859 860 do { 861 level = 0; 862 list_for_each_entry(p, &cl->children, siblings) { 863 if (p->level >= level) 864 level = p->level + 1; 865 } 866 cl->level = level; 867 } while ((cl = cl->cl_parent) != NULL); 868 } 869 870 static inline struct hfsc_class * 871 hfsc_find_class(u32 classid, struct Qdisc *sch) 872 { 873 struct hfsc_sched *q = qdisc_priv(sch); 874 struct Qdisc_class_common *clc; 875 876 clc = qdisc_class_find(&q->clhash, classid); 877 if (clc == NULL) 878 return NULL; 879 return container_of(clc, struct hfsc_class, cl_common); 880 } 881 882 static void 883 hfsc_change_rsc(struct hfsc_class *cl, struct tc_service_curve *rsc, 884 u64 cur_time) 885 { 886 sc2isc(rsc, &cl->cl_rsc); 887 rtsc_init(&cl->cl_deadline, &cl->cl_rsc, cur_time, cl->cl_cumul); 888 cl->cl_eligible = cl->cl_deadline; 889 if (cl->cl_rsc.sm1 <= cl->cl_rsc.sm2) { 890 cl->cl_eligible.dx = 0; 891 cl->cl_eligible.dy = 0; 892 } 893 cl->cl_flags |= HFSC_RSC; 894 } 895 896 static void 897 hfsc_change_fsc(struct hfsc_class *cl, struct tc_service_curve *fsc) 898 { 899 sc2isc(fsc, &cl->cl_fsc); 900 rtsc_init(&cl->cl_virtual, &cl->cl_fsc, cl->cl_vt, cl->cl_total); 901 cl->cl_flags |= HFSC_FSC; 902 } 903 904 static void 905 hfsc_change_usc(struct hfsc_class *cl, struct tc_service_curve *usc, 906 u64 cur_time) 907 { 908 sc2isc(usc, &cl->cl_usc); 909 rtsc_init(&cl->cl_ulimit, &cl->cl_usc, cur_time, cl->cl_total); 910 cl->cl_flags |= HFSC_USC; 911 } 912 913 static void 914 hfsc_upgrade_rt(struct hfsc_class *cl) 915 { 916 cl->cl_fsc = cl->cl_rsc; 917 rtsc_init(&cl->cl_virtual, &cl->cl_fsc, cl->cl_vt, cl->cl_total); 918 cl->cl_flags |= HFSC_FSC; 919 } 920 921 static const struct nla_policy hfsc_policy[TCA_HFSC_MAX + 1] = { 922 [TCA_HFSC_RSC] = { .len = sizeof(struct tc_service_curve) }, 923 [TCA_HFSC_FSC] = { .len = sizeof(struct tc_service_curve) }, 924 [TCA_HFSC_USC] = { .len = sizeof(struct tc_service_curve) }, 925 }; 926 927 static int 928 hfsc_change_class(struct Qdisc *sch, u32 classid, u32 parentid, 929 struct nlattr **tca, unsigned long *arg, 930 struct netlink_ext_ack *extack) 931 { 932 struct hfsc_sched *q = qdisc_priv(sch); 933 struct hfsc_class *cl = (struct hfsc_class *)*arg; 934 struct hfsc_class *parent = NULL; 935 struct nlattr *opt = tca[TCA_OPTIONS]; 936 struct nlattr *tb[TCA_HFSC_MAX + 1]; 937 struct tc_service_curve *rsc = NULL, *fsc = NULL, *usc = NULL; 938 u64 cur_time; 939 int err; 940 941 if (opt == NULL) 942 return -EINVAL; 943 944 err = nla_parse_nested_deprecated(tb, TCA_HFSC_MAX, opt, hfsc_policy, 945 NULL); 946 if (err < 0) 947 return err; 948 949 if (tb[TCA_HFSC_RSC]) { 950 rsc = nla_data(tb[TCA_HFSC_RSC]); 951 if (rsc->m1 == 0 && rsc->m2 == 0) 952 rsc = NULL; 953 } 954 955 if (tb[TCA_HFSC_FSC]) { 956 fsc = nla_data(tb[TCA_HFSC_FSC]); 957 if (fsc->m1 == 0 && fsc->m2 == 0) 958 fsc = NULL; 959 } 960 961 if (tb[TCA_HFSC_USC]) { 962 usc = nla_data(tb[TCA_HFSC_USC]); 963 if (usc->m1 == 0 && usc->m2 == 0) 964 usc = NULL; 965 } 966 967 if (cl != NULL) { 968 int old_flags; 969 int len = 0; 970 971 if (parentid) { 972 if (cl->cl_parent && 973 cl->cl_parent->cl_common.classid != parentid) 974 return -EINVAL; 975 if (cl->cl_parent == NULL && parentid != TC_H_ROOT) 976 return -EINVAL; 977 } 978 cur_time = psched_get_time(); 979 980 if (tca[TCA_RATE]) { 981 err = gen_replace_estimator(&cl->bstats, NULL, 982 &cl->rate_est, 983 NULL, 984 true, 985 tca[TCA_RATE]); 986 if (err) 987 return err; 988 } 989 990 sch_tree_lock(sch); 991 old_flags = cl->cl_flags; 992 993 if (rsc != NULL) 994 hfsc_change_rsc(cl, rsc, cur_time); 995 if (fsc != NULL) 996 hfsc_change_fsc(cl, fsc); 997 if (usc != NULL) 998 hfsc_change_usc(cl, usc, cur_time); 999 1000 if (cl->qdisc->q.qlen != 0) 1001 len = qdisc_peek_len(cl->qdisc); 1002 /* Check queue length again since some qdisc implementations 1003 * (e.g., netem/codel) might empty the queue during the peek 1004 * operation. 1005 */ 1006 if (cl->qdisc->q.qlen != 0) { 1007 if (cl->cl_flags & HFSC_RSC) { 1008 if (old_flags & HFSC_RSC) 1009 update_ed(cl, len); 1010 else 1011 init_ed(cl, len); 1012 } 1013 1014 if (cl->cl_flags & HFSC_FSC) { 1015 if (old_flags & HFSC_FSC) 1016 update_vf(cl, 0, cur_time); 1017 else 1018 init_vf(cl, len); 1019 } 1020 } 1021 sch_tree_unlock(sch); 1022 1023 return 0; 1024 } 1025 1026 if (parentid == TC_H_ROOT) 1027 return -EEXIST; 1028 1029 parent = &q->root; 1030 if (parentid) { 1031 parent = hfsc_find_class(parentid, sch); 1032 if (parent == NULL) 1033 return -ENOENT; 1034 } 1035 1036 if (classid == 0 || TC_H_MAJ(classid ^ sch->handle) != 0) 1037 return -EINVAL; 1038 if (hfsc_find_class(classid, sch)) 1039 return -EEXIST; 1040 1041 if (rsc == NULL && fsc == NULL) 1042 return -EINVAL; 1043 1044 cl = kzalloc(sizeof(struct hfsc_class), GFP_KERNEL); 1045 if (cl == NULL) 1046 return -ENOBUFS; 1047 1048 RB_CLEAR_NODE(&cl->el_node); 1049 1050 err = tcf_block_get(&cl->block, &cl->filter_list, sch, extack); 1051 if (err) { 1052 kfree(cl); 1053 return err; 1054 } 1055 1056 if (tca[TCA_RATE]) { 1057 err = gen_new_estimator(&cl->bstats, NULL, &cl->rate_est, 1058 NULL, true, tca[TCA_RATE]); 1059 if (err) { 1060 tcf_block_put(cl->block); 1061 kfree(cl); 1062 return err; 1063 } 1064 } 1065 1066 if (rsc != NULL) 1067 hfsc_change_rsc(cl, rsc, 0); 1068 if (fsc != NULL) 1069 hfsc_change_fsc(cl, fsc); 1070 if (usc != NULL) 1071 hfsc_change_usc(cl, usc, 0); 1072 1073 cl->cl_common.classid = classid; 1074 cl->sched = q; 1075 cl->cl_parent = parent; 1076 cl->qdisc = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops, 1077 classid, NULL); 1078 if (cl->qdisc == NULL) 1079 cl->qdisc = &noop_qdisc; 1080 else 1081 qdisc_hash_add(cl->qdisc, true); 1082 INIT_LIST_HEAD(&cl->children); 1083 cl->vt_tree = RB_ROOT; 1084 cl->cf_tree = RB_ROOT; 1085 1086 sch_tree_lock(sch); 1087 /* Check if the inner class is a misconfigured 'rt' */ 1088 if (!(parent->cl_flags & HFSC_FSC) && parent != &q->root) { 1089 NL_SET_ERR_MSG(extack, 1090 "Forced curve change on parent 'rt' to 'sc'"); 1091 hfsc_upgrade_rt(parent); 1092 } 1093 qdisc_class_hash_insert(&q->clhash, &cl->cl_common); 1094 list_add_tail(&cl->siblings, &parent->children); 1095 if (parent->level == 0) 1096 qdisc_purge_queue(parent->qdisc); 1097 hfsc_adjust_levels(parent); 1098 sch_tree_unlock(sch); 1099 1100 qdisc_class_hash_grow(sch, &q->clhash); 1101 1102 *arg = (unsigned long)cl; 1103 return 0; 1104 } 1105 1106 static void 1107 hfsc_destroy_class(struct Qdisc *sch, struct hfsc_class *cl) 1108 { 1109 struct hfsc_sched *q = qdisc_priv(sch); 1110 1111 tcf_block_put(cl->block); 1112 qdisc_put(cl->qdisc); 1113 gen_kill_estimator(&cl->rate_est); 1114 if (cl != &q->root) 1115 kfree(cl); 1116 } 1117 1118 static int 1119 hfsc_delete_class(struct Qdisc *sch, unsigned long arg, 1120 struct netlink_ext_ack *extack) 1121 { 1122 struct hfsc_sched *q = qdisc_priv(sch); 1123 struct hfsc_class *cl = (struct hfsc_class *)arg; 1124 1125 if (cl->level > 0 || qdisc_class_in_use(&cl->cl_common) || 1126 cl == &q->root) { 1127 NL_SET_ERR_MSG(extack, "HFSC class in use"); 1128 return -EBUSY; 1129 } 1130 1131 sch_tree_lock(sch); 1132 1133 list_del(&cl->siblings); 1134 hfsc_adjust_levels(cl->cl_parent); 1135 1136 qdisc_purge_queue(cl->qdisc); 1137 qdisc_class_hash_remove(&q->clhash, &cl->cl_common); 1138 1139 sch_tree_unlock(sch); 1140 1141 hfsc_destroy_class(sch, cl); 1142 return 0; 1143 } 1144 1145 static struct hfsc_class * 1146 hfsc_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr) 1147 { 1148 struct hfsc_sched *q = qdisc_priv(sch); 1149 struct hfsc_class *head, *cl; 1150 struct tcf_result res; 1151 struct tcf_proto *tcf; 1152 int result; 1153 1154 if (TC_H_MAJ(skb->priority ^ sch->handle) == 0 && 1155 (cl = hfsc_find_class(skb->priority, sch)) != NULL) 1156 if (cl->level == 0) 1157 return cl; 1158 1159 *qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS; 1160 head = &q->root; 1161 tcf = rcu_dereference_bh(q->root.filter_list); 1162 while (tcf && (result = tcf_classify(skb, NULL, tcf, &res, false)) >= 0) { 1163 #ifdef CONFIG_NET_CLS_ACT 1164 switch (result) { 1165 case TC_ACT_QUEUED: 1166 case TC_ACT_STOLEN: 1167 case TC_ACT_TRAP: 1168 *qerr = NET_XMIT_SUCCESS | __NET_XMIT_STOLEN; 1169 fallthrough; 1170 case TC_ACT_SHOT: 1171 return NULL; 1172 } 1173 #endif 1174 cl = (struct hfsc_class *)res.class; 1175 if (!cl) { 1176 cl = hfsc_find_class(res.classid, sch); 1177 if (!cl) 1178 break; /* filter selected invalid classid */ 1179 if (cl->level >= head->level) 1180 break; /* filter may only point downwards */ 1181 } 1182 1183 if (cl->level == 0) 1184 return cl; /* hit leaf class */ 1185 1186 /* apply inner filter chain */ 1187 tcf = rcu_dereference_bh(cl->filter_list); 1188 head = cl; 1189 } 1190 1191 /* classification failed, try default class */ 1192 cl = hfsc_find_class(TC_H_MAKE(TC_H_MAJ(sch->handle), 1193 READ_ONCE(q->defcls)), sch); 1194 if (cl == NULL || cl->level > 0) 1195 return NULL; 1196 1197 return cl; 1198 } 1199 1200 static int 1201 hfsc_graft_class(struct Qdisc *sch, unsigned long arg, struct Qdisc *new, 1202 struct Qdisc **old, struct netlink_ext_ack *extack) 1203 { 1204 struct hfsc_class *cl = (struct hfsc_class *)arg; 1205 1206 if (cl->level > 0) 1207 return -EINVAL; 1208 if (new == NULL) { 1209 new = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops, 1210 cl->cl_common.classid, NULL); 1211 if (new == NULL) 1212 new = &noop_qdisc; 1213 } 1214 1215 *old = qdisc_replace(sch, new, &cl->qdisc); 1216 return 0; 1217 } 1218 1219 static struct Qdisc * 1220 hfsc_class_leaf(struct Qdisc *sch, unsigned long arg) 1221 { 1222 struct hfsc_class *cl = (struct hfsc_class *)arg; 1223 1224 if (cl->level == 0) 1225 return cl->qdisc; 1226 1227 return NULL; 1228 } 1229 1230 static void 1231 hfsc_qlen_notify(struct Qdisc *sch, unsigned long arg) 1232 { 1233 struct hfsc_class *cl = (struct hfsc_class *)arg; 1234 1235 /* vttree is now handled in update_vf() so that update_vf(cl, 0, 0) 1236 * needs to be called explicitly to remove a class from vttree. 1237 */ 1238 if (cl->cl_nactive) 1239 update_vf(cl, 0, 0); 1240 if (cl->cl_flags & HFSC_RSC) 1241 eltree_remove(cl); 1242 } 1243 1244 static unsigned long 1245 hfsc_search_class(struct Qdisc *sch, u32 classid) 1246 { 1247 return (unsigned long)hfsc_find_class(classid, sch); 1248 } 1249 1250 static unsigned long 1251 hfsc_bind_tcf(struct Qdisc *sch, unsigned long parent, u32 classid) 1252 { 1253 struct hfsc_class *p = (struct hfsc_class *)parent; 1254 struct hfsc_class *cl = hfsc_find_class(classid, sch); 1255 1256 if (cl != NULL) { 1257 if (p != NULL && p->level <= cl->level) 1258 return 0; 1259 qdisc_class_get(&cl->cl_common); 1260 } 1261 1262 return (unsigned long)cl; 1263 } 1264 1265 static void 1266 hfsc_unbind_tcf(struct Qdisc *sch, unsigned long arg) 1267 { 1268 struct hfsc_class *cl = (struct hfsc_class *)arg; 1269 1270 qdisc_class_put(&cl->cl_common); 1271 } 1272 1273 static struct tcf_block *hfsc_tcf_block(struct Qdisc *sch, unsigned long arg, 1274 struct netlink_ext_ack *extack) 1275 { 1276 struct hfsc_sched *q = qdisc_priv(sch); 1277 struct hfsc_class *cl = (struct hfsc_class *)arg; 1278 1279 if (cl == NULL) 1280 cl = &q->root; 1281 1282 return cl->block; 1283 } 1284 1285 static int 1286 hfsc_dump_sc(struct sk_buff *skb, int attr, struct internal_sc *sc) 1287 { 1288 struct tc_service_curve tsc; 1289 1290 tsc.m1 = sm2m(sc->sm1); 1291 tsc.d = dx2d(sc->dx); 1292 tsc.m2 = sm2m(sc->sm2); 1293 if (nla_put(skb, attr, sizeof(tsc), &tsc)) 1294 goto nla_put_failure; 1295 1296 return skb->len; 1297 1298 nla_put_failure: 1299 return -1; 1300 } 1301 1302 static int 1303 hfsc_dump_curves(struct sk_buff *skb, struct hfsc_class *cl) 1304 { 1305 if ((cl->cl_flags & HFSC_RSC) && 1306 (hfsc_dump_sc(skb, TCA_HFSC_RSC, &cl->cl_rsc) < 0)) 1307 goto nla_put_failure; 1308 1309 if ((cl->cl_flags & HFSC_FSC) && 1310 (hfsc_dump_sc(skb, TCA_HFSC_FSC, &cl->cl_fsc) < 0)) 1311 goto nla_put_failure; 1312 1313 if ((cl->cl_flags & HFSC_USC) && 1314 (hfsc_dump_sc(skb, TCA_HFSC_USC, &cl->cl_usc) < 0)) 1315 goto nla_put_failure; 1316 1317 return skb->len; 1318 1319 nla_put_failure: 1320 return -1; 1321 } 1322 1323 static int 1324 hfsc_dump_class(struct Qdisc *sch, unsigned long arg, struct sk_buff *skb, 1325 struct tcmsg *tcm) 1326 { 1327 struct hfsc_class *cl = (struct hfsc_class *)arg; 1328 struct nlattr *nest; 1329 1330 tcm->tcm_parent = cl->cl_parent ? cl->cl_parent->cl_common.classid : 1331 TC_H_ROOT; 1332 tcm->tcm_handle = cl->cl_common.classid; 1333 if (cl->level == 0) 1334 tcm->tcm_info = cl->qdisc->handle; 1335 1336 nest = nla_nest_start_noflag(skb, TCA_OPTIONS); 1337 if (nest == NULL) 1338 goto nla_put_failure; 1339 if (hfsc_dump_curves(skb, cl) < 0) 1340 goto nla_put_failure; 1341 return nla_nest_end(skb, nest); 1342 1343 nla_put_failure: 1344 nla_nest_cancel(skb, nest); 1345 return -EMSGSIZE; 1346 } 1347 1348 static int 1349 hfsc_dump_class_stats(struct Qdisc *sch, unsigned long arg, 1350 struct gnet_dump *d) 1351 { 1352 struct hfsc_class *cl = (struct hfsc_class *)arg; 1353 struct tc_hfsc_stats xstats; 1354 __u32 qlen; 1355 1356 qdisc_qstats_qlen_backlog(cl->qdisc, &qlen, &cl->qstats.backlog); 1357 xstats.level = cl->level; 1358 xstats.period = cl->cl_vtperiod; 1359 xstats.work = cl->cl_total; 1360 xstats.rtwork = cl->cl_cumul; 1361 1362 if (gnet_stats_copy_basic(d, NULL, &cl->bstats, true) < 0 || 1363 gnet_stats_copy_rate_est(d, &cl->rate_est) < 0 || 1364 gnet_stats_copy_queue(d, NULL, &cl->qstats, qlen) < 0) 1365 return -1; 1366 1367 return gnet_stats_copy_app(d, &xstats, sizeof(xstats)); 1368 } 1369 1370 1371 1372 static void 1373 hfsc_walk(struct Qdisc *sch, struct qdisc_walker *arg) 1374 { 1375 struct hfsc_sched *q = qdisc_priv(sch); 1376 struct hfsc_class *cl; 1377 unsigned int i; 1378 1379 if (arg->stop) 1380 return; 1381 1382 for (i = 0; i < q->clhash.hashsize; i++) { 1383 hlist_for_each_entry(cl, &q->clhash.hash[i], 1384 cl_common.hnode) { 1385 if (!tc_qdisc_stats_dump(sch, (unsigned long)cl, arg)) 1386 return; 1387 } 1388 } 1389 } 1390 1391 static void 1392 hfsc_schedule_watchdog(struct Qdisc *sch) 1393 { 1394 struct hfsc_sched *q = qdisc_priv(sch); 1395 struct hfsc_class *cl; 1396 u64 next_time = 0; 1397 1398 cl = eltree_get_minel(q); 1399 if (cl) 1400 next_time = cl->cl_e; 1401 if (q->root.cl_cfmin != 0) { 1402 if (next_time == 0 || next_time > q->root.cl_cfmin) 1403 next_time = q->root.cl_cfmin; 1404 } 1405 if (next_time) 1406 qdisc_watchdog_schedule(&q->watchdog, next_time); 1407 } 1408 1409 static int 1410 hfsc_init_qdisc(struct Qdisc *sch, struct nlattr *opt, 1411 struct netlink_ext_ack *extack) 1412 { 1413 struct hfsc_sched *q = qdisc_priv(sch); 1414 struct tc_hfsc_qopt *qopt; 1415 int err; 1416 1417 qdisc_watchdog_init(&q->watchdog, sch); 1418 1419 if (!opt || nla_len(opt) < sizeof(*qopt)) 1420 return -EINVAL; 1421 qopt = nla_data(opt); 1422 1423 q->defcls = qopt->defcls; 1424 err = qdisc_class_hash_init(&q->clhash); 1425 if (err < 0) 1426 return err; 1427 q->eligible = RB_ROOT; 1428 1429 err = tcf_block_get(&q->root.block, &q->root.filter_list, sch, extack); 1430 if (err) 1431 return err; 1432 1433 gnet_stats_basic_sync_init(&q->root.bstats); 1434 q->root.cl_common.classid = sch->handle; 1435 q->root.sched = q; 1436 q->root.qdisc = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops, 1437 sch->handle, NULL); 1438 if (q->root.qdisc == NULL) 1439 q->root.qdisc = &noop_qdisc; 1440 else 1441 qdisc_hash_add(q->root.qdisc, true); 1442 INIT_LIST_HEAD(&q->root.children); 1443 q->root.vt_tree = RB_ROOT; 1444 q->root.cf_tree = RB_ROOT; 1445 1446 qdisc_class_hash_insert(&q->clhash, &q->root.cl_common); 1447 qdisc_class_hash_grow(sch, &q->clhash); 1448 1449 return 0; 1450 } 1451 1452 static int 1453 hfsc_change_qdisc(struct Qdisc *sch, struct nlattr *opt, 1454 struct netlink_ext_ack *extack) 1455 { 1456 struct hfsc_sched *q = qdisc_priv(sch); 1457 struct tc_hfsc_qopt *qopt; 1458 1459 if (nla_len(opt) < sizeof(*qopt)) 1460 return -EINVAL; 1461 qopt = nla_data(opt); 1462 1463 WRITE_ONCE(q->defcls, qopt->defcls); 1464 1465 return 0; 1466 } 1467 1468 static void 1469 hfsc_reset_class(struct hfsc_class *cl) 1470 { 1471 cl->cl_total = 0; 1472 cl->cl_cumul = 0; 1473 cl->cl_d = 0; 1474 cl->cl_e = 0; 1475 cl->cl_vt = 0; 1476 cl->cl_vtadj = 0; 1477 cl->cl_cvtmin = 0; 1478 cl->cl_cvtoff = 0; 1479 cl->cl_vtperiod = 0; 1480 cl->cl_parentperiod = 0; 1481 cl->cl_f = 0; 1482 cl->cl_myf = 0; 1483 cl->cl_cfmin = 0; 1484 cl->cl_nactive = 0; 1485 1486 cl->vt_tree = RB_ROOT; 1487 cl->cf_tree = RB_ROOT; 1488 qdisc_reset(cl->qdisc); 1489 1490 if (cl->cl_flags & HFSC_RSC) 1491 rtsc_init(&cl->cl_deadline, &cl->cl_rsc, 0, 0); 1492 if (cl->cl_flags & HFSC_FSC) 1493 rtsc_init(&cl->cl_virtual, &cl->cl_fsc, 0, 0); 1494 if (cl->cl_flags & HFSC_USC) 1495 rtsc_init(&cl->cl_ulimit, &cl->cl_usc, 0, 0); 1496 } 1497 1498 static void 1499 hfsc_reset_qdisc(struct Qdisc *sch) 1500 { 1501 struct hfsc_sched *q = qdisc_priv(sch); 1502 struct hfsc_class *cl; 1503 unsigned int i; 1504 1505 for (i = 0; i < q->clhash.hashsize; i++) { 1506 hlist_for_each_entry(cl, &q->clhash.hash[i], cl_common.hnode) 1507 hfsc_reset_class(cl); 1508 } 1509 q->eligible = RB_ROOT; 1510 qdisc_watchdog_cancel(&q->watchdog); 1511 } 1512 1513 static void 1514 hfsc_destroy_qdisc(struct Qdisc *sch) 1515 { 1516 struct hfsc_sched *q = qdisc_priv(sch); 1517 struct hlist_node *next; 1518 struct hfsc_class *cl; 1519 unsigned int i; 1520 1521 for (i = 0; i < q->clhash.hashsize; i++) { 1522 hlist_for_each_entry(cl, &q->clhash.hash[i], cl_common.hnode) { 1523 tcf_block_put(cl->block); 1524 cl->block = NULL; 1525 } 1526 } 1527 for (i = 0; i < q->clhash.hashsize; i++) { 1528 hlist_for_each_entry_safe(cl, next, &q->clhash.hash[i], 1529 cl_common.hnode) 1530 hfsc_destroy_class(sch, cl); 1531 } 1532 qdisc_class_hash_destroy(&q->clhash); 1533 qdisc_watchdog_cancel(&q->watchdog); 1534 } 1535 1536 static int 1537 hfsc_dump_qdisc(struct Qdisc *sch, struct sk_buff *skb) 1538 { 1539 struct hfsc_sched *q = qdisc_priv(sch); 1540 unsigned char *b = skb_tail_pointer(skb); 1541 struct tc_hfsc_qopt qopt; 1542 1543 qopt.defcls = READ_ONCE(q->defcls); 1544 if (nla_put(skb, TCA_OPTIONS, sizeof(qopt), &qopt)) 1545 goto nla_put_failure; 1546 return skb->len; 1547 1548 nla_put_failure: 1549 nlmsg_trim(skb, b); 1550 return -1; 1551 } 1552 1553 static int 1554 hfsc_enqueue(struct sk_buff *skb, struct Qdisc *sch, struct sk_buff **to_free) 1555 { 1556 unsigned int len = qdisc_pkt_len(skb); 1557 struct hfsc_class *cl; 1558 int err; 1559 bool first; 1560 1561 cl = hfsc_classify(skb, sch, &err); 1562 if (cl == NULL) { 1563 if (err & __NET_XMIT_BYPASS) 1564 qdisc_qstats_drop(sch); 1565 __qdisc_drop(skb, to_free); 1566 return err; 1567 } 1568 1569 first = !cl->qdisc->q.qlen; 1570 err = qdisc_enqueue(skb, cl->qdisc, to_free); 1571 if (unlikely(err != NET_XMIT_SUCCESS)) { 1572 if (net_xmit_drop_count(err)) { 1573 cl->qstats.drops++; 1574 qdisc_qstats_drop(sch); 1575 } 1576 return err; 1577 } 1578 1579 sch->qstats.backlog += len; 1580 sch->q.qlen++; 1581 1582 if (first && !cl_in_el_or_vttree(cl)) { 1583 if (cl->cl_flags & HFSC_RSC) 1584 init_ed(cl, len); 1585 if (cl->cl_flags & HFSC_FSC) 1586 init_vf(cl, len); 1587 /* 1588 * If this is the first packet, isolate the head so an eventual 1589 * head drop before the first dequeue operation has no chance 1590 * to invalidate the deadline. 1591 */ 1592 if (cl->cl_flags & HFSC_RSC) 1593 cl->qdisc->ops->peek(cl->qdisc); 1594 1595 } 1596 1597 return NET_XMIT_SUCCESS; 1598 } 1599 1600 static struct sk_buff * 1601 hfsc_dequeue(struct Qdisc *sch) 1602 { 1603 struct hfsc_sched *q = qdisc_priv(sch); 1604 struct hfsc_class *cl; 1605 struct sk_buff *skb; 1606 u64 cur_time; 1607 unsigned int next_len; 1608 int realtime = 0; 1609 1610 if (sch->q.qlen == 0) 1611 return NULL; 1612 1613 cur_time = psched_get_time(); 1614 1615 /* 1616 * if there are eligible classes, use real-time criteria. 1617 * find the class with the minimum deadline among 1618 * the eligible classes. 1619 */ 1620 cl = eltree_get_mindl(q, cur_time); 1621 if (cl) { 1622 realtime = 1; 1623 } else { 1624 /* 1625 * use link-sharing criteria 1626 * get the class with the minimum vt in the hierarchy 1627 */ 1628 cl = vttree_get_minvt(&q->root, cur_time); 1629 if (cl == NULL) { 1630 qdisc_qstats_overlimit(sch); 1631 hfsc_schedule_watchdog(sch); 1632 return NULL; 1633 } 1634 } 1635 1636 skb = qdisc_dequeue_peeked(cl->qdisc); 1637 if (skb == NULL) { 1638 qdisc_warn_nonwc("HFSC", cl->qdisc); 1639 return NULL; 1640 } 1641 1642 bstats_update(&cl->bstats, skb); 1643 update_vf(cl, qdisc_pkt_len(skb), cur_time); 1644 if (realtime) 1645 cl->cl_cumul += qdisc_pkt_len(skb); 1646 1647 if (cl->cl_flags & HFSC_RSC) { 1648 if (cl->qdisc->q.qlen != 0) { 1649 /* update ed */ 1650 next_len = qdisc_peek_len(cl->qdisc); 1651 /* Check queue length again since some qdisc implementations 1652 * (e.g., netem/codel) might empty the queue during the peek 1653 * operation. 1654 */ 1655 if (cl->qdisc->q.qlen != 0) { 1656 if (realtime) 1657 update_ed(cl, next_len); 1658 else 1659 update_d(cl, next_len); 1660 } 1661 } else { 1662 /* the class becomes passive */ 1663 eltree_remove(cl); 1664 } 1665 } 1666 1667 qdisc_bstats_update(sch, skb); 1668 qdisc_qstats_backlog_dec(sch, skb); 1669 sch->q.qlen--; 1670 1671 return skb; 1672 } 1673 1674 static const struct Qdisc_class_ops hfsc_class_ops = { 1675 .change = hfsc_change_class, 1676 .delete = hfsc_delete_class, 1677 .graft = hfsc_graft_class, 1678 .leaf = hfsc_class_leaf, 1679 .qlen_notify = hfsc_qlen_notify, 1680 .find = hfsc_search_class, 1681 .bind_tcf = hfsc_bind_tcf, 1682 .unbind_tcf = hfsc_unbind_tcf, 1683 .tcf_block = hfsc_tcf_block, 1684 .dump = hfsc_dump_class, 1685 .dump_stats = hfsc_dump_class_stats, 1686 .walk = hfsc_walk 1687 }; 1688 1689 static struct Qdisc_ops hfsc_qdisc_ops __read_mostly = { 1690 .id = "hfsc", 1691 .init = hfsc_init_qdisc, 1692 .change = hfsc_change_qdisc, 1693 .reset = hfsc_reset_qdisc, 1694 .destroy = hfsc_destroy_qdisc, 1695 .dump = hfsc_dump_qdisc, 1696 .enqueue = hfsc_enqueue, 1697 .dequeue = hfsc_dequeue, 1698 .peek = qdisc_peek_dequeued, 1699 .cl_ops = &hfsc_class_ops, 1700 .priv_size = sizeof(struct hfsc_sched), 1701 .owner = THIS_MODULE 1702 }; 1703 MODULE_ALIAS_NET_SCH("hfsc"); 1704 1705 static int __init 1706 hfsc_init(void) 1707 { 1708 return register_qdisc(&hfsc_qdisc_ops); 1709 } 1710 1711 static void __exit 1712 hfsc_cleanup(void) 1713 { 1714 unregister_qdisc(&hfsc_qdisc_ops); 1715 } 1716 1717 MODULE_LICENSE("GPL"); 1718 MODULE_DESCRIPTION("Hierarchical Fair Service Curve scheduler"); 1719 module_init(hfsc_init); 1720 module_exit(hfsc_cleanup); 1721