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 void 839 hfsc_adjust_levels(struct hfsc_class *cl) 840 { 841 struct hfsc_class *p; 842 unsigned int level; 843 844 do { 845 level = 0; 846 list_for_each_entry(p, &cl->children, siblings) { 847 if (p->level >= level) 848 level = p->level + 1; 849 } 850 cl->level = level; 851 } while ((cl = cl->cl_parent) != NULL); 852 } 853 854 static inline struct hfsc_class * 855 hfsc_find_class(u32 classid, struct Qdisc *sch) 856 { 857 struct hfsc_sched *q = qdisc_priv(sch); 858 struct Qdisc_class_common *clc; 859 860 clc = qdisc_class_find(&q->clhash, classid); 861 if (clc == NULL) 862 return NULL; 863 return container_of(clc, struct hfsc_class, cl_common); 864 } 865 866 static void 867 hfsc_change_rsc(struct hfsc_class *cl, struct tc_service_curve *rsc, 868 u64 cur_time) 869 { 870 sc2isc(rsc, &cl->cl_rsc); 871 rtsc_init(&cl->cl_deadline, &cl->cl_rsc, cur_time, cl->cl_cumul); 872 cl->cl_eligible = cl->cl_deadline; 873 if (cl->cl_rsc.sm1 <= cl->cl_rsc.sm2) { 874 cl->cl_eligible.dx = 0; 875 cl->cl_eligible.dy = 0; 876 } 877 cl->cl_flags |= HFSC_RSC; 878 } 879 880 static void 881 hfsc_change_fsc(struct hfsc_class *cl, struct tc_service_curve *fsc) 882 { 883 sc2isc(fsc, &cl->cl_fsc); 884 rtsc_init(&cl->cl_virtual, &cl->cl_fsc, cl->cl_vt, cl->cl_total); 885 cl->cl_flags |= HFSC_FSC; 886 } 887 888 static void 889 hfsc_change_usc(struct hfsc_class *cl, struct tc_service_curve *usc, 890 u64 cur_time) 891 { 892 sc2isc(usc, &cl->cl_usc); 893 rtsc_init(&cl->cl_ulimit, &cl->cl_usc, cur_time, cl->cl_total); 894 cl->cl_flags |= HFSC_USC; 895 } 896 897 static void 898 hfsc_upgrade_rt(struct hfsc_class *cl) 899 { 900 cl->cl_fsc = cl->cl_rsc; 901 rtsc_init(&cl->cl_virtual, &cl->cl_fsc, cl->cl_vt, cl->cl_total); 902 cl->cl_flags |= HFSC_FSC; 903 } 904 905 static const struct nla_policy hfsc_policy[TCA_HFSC_MAX + 1] = { 906 [TCA_HFSC_RSC] = { .len = sizeof(struct tc_service_curve) }, 907 [TCA_HFSC_FSC] = { .len = sizeof(struct tc_service_curve) }, 908 [TCA_HFSC_USC] = { .len = sizeof(struct tc_service_curve) }, 909 }; 910 911 static int 912 hfsc_change_class(struct Qdisc *sch, u32 classid, u32 parentid, 913 struct nlattr **tca, unsigned long *arg, 914 struct netlink_ext_ack *extack) 915 { 916 struct hfsc_sched *q = qdisc_priv(sch); 917 struct hfsc_class *cl = (struct hfsc_class *)*arg; 918 struct hfsc_class *parent = NULL; 919 struct nlattr *opt = tca[TCA_OPTIONS]; 920 struct nlattr *tb[TCA_HFSC_MAX + 1]; 921 struct tc_service_curve *rsc = NULL, *fsc = NULL, *usc = NULL; 922 u64 cur_time; 923 int err; 924 925 if (opt == NULL) 926 return -EINVAL; 927 928 err = nla_parse_nested_deprecated(tb, TCA_HFSC_MAX, opt, hfsc_policy, 929 NULL); 930 if (err < 0) 931 return err; 932 933 if (tb[TCA_HFSC_RSC]) { 934 rsc = nla_data(tb[TCA_HFSC_RSC]); 935 if (rsc->m1 == 0 && rsc->m2 == 0) 936 rsc = NULL; 937 } 938 939 if (tb[TCA_HFSC_FSC]) { 940 fsc = nla_data(tb[TCA_HFSC_FSC]); 941 if (fsc->m1 == 0 && fsc->m2 == 0) 942 fsc = NULL; 943 } 944 945 if (tb[TCA_HFSC_USC]) { 946 usc = nla_data(tb[TCA_HFSC_USC]); 947 if (usc->m1 == 0 && usc->m2 == 0) 948 usc = NULL; 949 } 950 951 if (cl != NULL) { 952 int old_flags; 953 int len = 0; 954 955 if (parentid) { 956 if (cl->cl_parent && 957 cl->cl_parent->cl_common.classid != parentid) 958 return -EINVAL; 959 if (cl->cl_parent == NULL && parentid != TC_H_ROOT) 960 return -EINVAL; 961 } 962 cur_time = psched_get_time(); 963 964 if (tca[TCA_RATE]) { 965 err = gen_replace_estimator(&cl->bstats, NULL, 966 &cl->rate_est, 967 NULL, 968 true, 969 tca[TCA_RATE]); 970 if (err) 971 return err; 972 } 973 974 sch_tree_lock(sch); 975 old_flags = cl->cl_flags; 976 977 if (rsc != NULL) 978 hfsc_change_rsc(cl, rsc, cur_time); 979 if (fsc != NULL) 980 hfsc_change_fsc(cl, fsc); 981 if (usc != NULL) 982 hfsc_change_usc(cl, usc, cur_time); 983 984 if (cl->qdisc->q.qlen != 0) 985 len = qdisc_peek_len(cl->qdisc); 986 /* Check queue length again since some qdisc implementations 987 * (e.g., netem/codel) might empty the queue during the peek 988 * operation. 989 */ 990 if (cl->qdisc->q.qlen != 0) { 991 if (cl->cl_flags & HFSC_RSC) { 992 if (old_flags & HFSC_RSC) 993 update_ed(cl, len); 994 else 995 init_ed(cl, len); 996 } 997 998 if (cl->cl_flags & HFSC_FSC) { 999 if (old_flags & HFSC_FSC) 1000 update_vf(cl, 0, cur_time); 1001 else 1002 init_vf(cl, len); 1003 } 1004 } 1005 sch_tree_unlock(sch); 1006 1007 return 0; 1008 } 1009 1010 if (parentid == TC_H_ROOT) 1011 return -EEXIST; 1012 1013 parent = &q->root; 1014 if (parentid) { 1015 parent = hfsc_find_class(parentid, sch); 1016 if (parent == NULL) 1017 return -ENOENT; 1018 } 1019 1020 if (classid == 0 || TC_H_MAJ(classid ^ sch->handle) != 0) 1021 return -EINVAL; 1022 if (hfsc_find_class(classid, sch)) 1023 return -EEXIST; 1024 1025 if (rsc == NULL && fsc == NULL) 1026 return -EINVAL; 1027 1028 cl = kzalloc(sizeof(struct hfsc_class), GFP_KERNEL); 1029 if (cl == NULL) 1030 return -ENOBUFS; 1031 1032 RB_CLEAR_NODE(&cl->el_node); 1033 1034 err = tcf_block_get(&cl->block, &cl->filter_list, sch, extack); 1035 if (err) { 1036 kfree(cl); 1037 return err; 1038 } 1039 1040 if (tca[TCA_RATE]) { 1041 err = gen_new_estimator(&cl->bstats, NULL, &cl->rate_est, 1042 NULL, true, tca[TCA_RATE]); 1043 if (err) { 1044 tcf_block_put(cl->block); 1045 kfree(cl); 1046 return err; 1047 } 1048 } 1049 1050 if (rsc != NULL) 1051 hfsc_change_rsc(cl, rsc, 0); 1052 if (fsc != NULL) 1053 hfsc_change_fsc(cl, fsc); 1054 if (usc != NULL) 1055 hfsc_change_usc(cl, usc, 0); 1056 1057 cl->cl_common.classid = classid; 1058 cl->sched = q; 1059 cl->cl_parent = parent; 1060 cl->qdisc = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops, 1061 classid, NULL); 1062 if (cl->qdisc == NULL) 1063 cl->qdisc = &noop_qdisc; 1064 else 1065 qdisc_hash_add(cl->qdisc, true); 1066 INIT_LIST_HEAD(&cl->children); 1067 cl->vt_tree = RB_ROOT; 1068 cl->cf_tree = RB_ROOT; 1069 1070 sch_tree_lock(sch); 1071 /* Check if the inner class is a misconfigured 'rt' */ 1072 if (!(parent->cl_flags & HFSC_FSC) && parent != &q->root) { 1073 NL_SET_ERR_MSG(extack, 1074 "Forced curve change on parent 'rt' to 'sc'"); 1075 hfsc_upgrade_rt(parent); 1076 } 1077 qdisc_class_hash_insert(&q->clhash, &cl->cl_common); 1078 list_add_tail(&cl->siblings, &parent->children); 1079 if (parent->level == 0) 1080 qdisc_purge_queue(parent->qdisc); 1081 hfsc_adjust_levels(parent); 1082 sch_tree_unlock(sch); 1083 1084 qdisc_class_hash_grow(sch, &q->clhash); 1085 1086 *arg = (unsigned long)cl; 1087 return 0; 1088 } 1089 1090 static void 1091 hfsc_destroy_class(struct Qdisc *sch, struct hfsc_class *cl) 1092 { 1093 struct hfsc_sched *q = qdisc_priv(sch); 1094 1095 tcf_block_put(cl->block); 1096 qdisc_put(cl->qdisc); 1097 gen_kill_estimator(&cl->rate_est); 1098 if (cl != &q->root) 1099 kfree(cl); 1100 } 1101 1102 static int 1103 hfsc_delete_class(struct Qdisc *sch, unsigned long arg, 1104 struct netlink_ext_ack *extack) 1105 { 1106 struct hfsc_sched *q = qdisc_priv(sch); 1107 struct hfsc_class *cl = (struct hfsc_class *)arg; 1108 1109 if (cl->level > 0 || qdisc_class_in_use(&cl->cl_common) || 1110 cl == &q->root) { 1111 NL_SET_ERR_MSG(extack, "HFSC class in use"); 1112 return -EBUSY; 1113 } 1114 1115 sch_tree_lock(sch); 1116 1117 list_del(&cl->siblings); 1118 hfsc_adjust_levels(cl->cl_parent); 1119 1120 qdisc_purge_queue(cl->qdisc); 1121 qdisc_class_hash_remove(&q->clhash, &cl->cl_common); 1122 1123 sch_tree_unlock(sch); 1124 1125 hfsc_destroy_class(sch, cl); 1126 return 0; 1127 } 1128 1129 static struct hfsc_class * 1130 hfsc_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr) 1131 { 1132 struct hfsc_sched *q = qdisc_priv(sch); 1133 struct hfsc_class *head, *cl; 1134 struct tcf_result res; 1135 struct tcf_proto *tcf; 1136 int result; 1137 1138 if (TC_H_MAJ(skb->priority ^ sch->handle) == 0 && 1139 (cl = hfsc_find_class(skb->priority, sch)) != NULL) 1140 if (cl->level == 0) 1141 return cl; 1142 1143 *qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS; 1144 head = &q->root; 1145 tcf = rcu_dereference_bh(q->root.filter_list); 1146 while (tcf && (result = tcf_classify(skb, NULL, tcf, &res, false)) >= 0) { 1147 #ifdef CONFIG_NET_CLS_ACT 1148 switch (result) { 1149 case TC_ACT_QUEUED: 1150 case TC_ACT_STOLEN: 1151 case TC_ACT_TRAP: 1152 *qerr = NET_XMIT_SUCCESS | __NET_XMIT_STOLEN; 1153 fallthrough; 1154 case TC_ACT_SHOT: 1155 return NULL; 1156 } 1157 #endif 1158 cl = (struct hfsc_class *)res.class; 1159 if (!cl) { 1160 cl = hfsc_find_class(res.classid, sch); 1161 if (!cl) 1162 break; /* filter selected invalid classid */ 1163 if (cl->level >= head->level) 1164 break; /* filter may only point downwards */ 1165 } 1166 1167 if (cl->level == 0) 1168 return cl; /* hit leaf class */ 1169 1170 /* apply inner filter chain */ 1171 tcf = rcu_dereference_bh(cl->filter_list); 1172 head = cl; 1173 } 1174 1175 /* classification failed, try default class */ 1176 cl = hfsc_find_class(TC_H_MAKE(TC_H_MAJ(sch->handle), 1177 READ_ONCE(q->defcls)), sch); 1178 if (cl == NULL || cl->level > 0) 1179 return NULL; 1180 1181 return cl; 1182 } 1183 1184 static int 1185 hfsc_graft_class(struct Qdisc *sch, unsigned long arg, struct Qdisc *new, 1186 struct Qdisc **old, struct netlink_ext_ack *extack) 1187 { 1188 struct hfsc_class *cl = (struct hfsc_class *)arg; 1189 1190 if (cl->level > 0) 1191 return -EINVAL; 1192 if (new == NULL) { 1193 new = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops, 1194 cl->cl_common.classid, NULL); 1195 if (new == NULL) 1196 new = &noop_qdisc; 1197 } 1198 1199 *old = qdisc_replace(sch, new, &cl->qdisc); 1200 return 0; 1201 } 1202 1203 static struct Qdisc * 1204 hfsc_class_leaf(struct Qdisc *sch, unsigned long arg) 1205 { 1206 struct hfsc_class *cl = (struct hfsc_class *)arg; 1207 1208 if (cl->level == 0) 1209 return cl->qdisc; 1210 1211 return NULL; 1212 } 1213 1214 static void 1215 hfsc_qlen_notify(struct Qdisc *sch, unsigned long arg) 1216 { 1217 struct hfsc_class *cl = (struct hfsc_class *)arg; 1218 1219 /* vttree is now handled in update_vf() so that update_vf(cl, 0, 0) 1220 * needs to be called explicitly to remove a class from vttree. 1221 */ 1222 if (cl->cl_nactive) 1223 update_vf(cl, 0, 0); 1224 if (cl->cl_flags & HFSC_RSC) 1225 eltree_remove(cl); 1226 } 1227 1228 static unsigned long 1229 hfsc_search_class(struct Qdisc *sch, u32 classid) 1230 { 1231 return (unsigned long)hfsc_find_class(classid, sch); 1232 } 1233 1234 static unsigned long 1235 hfsc_bind_tcf(struct Qdisc *sch, unsigned long parent, u32 classid) 1236 { 1237 struct hfsc_class *p = (struct hfsc_class *)parent; 1238 struct hfsc_class *cl = hfsc_find_class(classid, sch); 1239 1240 if (cl != NULL) { 1241 if (p != NULL && p->level <= cl->level) 1242 return 0; 1243 qdisc_class_get(&cl->cl_common); 1244 } 1245 1246 return (unsigned long)cl; 1247 } 1248 1249 static void 1250 hfsc_unbind_tcf(struct Qdisc *sch, unsigned long arg) 1251 { 1252 struct hfsc_class *cl = (struct hfsc_class *)arg; 1253 1254 qdisc_class_put(&cl->cl_common); 1255 } 1256 1257 static struct tcf_block *hfsc_tcf_block(struct Qdisc *sch, unsigned long arg, 1258 struct netlink_ext_ack *extack) 1259 { 1260 struct hfsc_sched *q = qdisc_priv(sch); 1261 struct hfsc_class *cl = (struct hfsc_class *)arg; 1262 1263 if (cl == NULL) 1264 cl = &q->root; 1265 1266 return cl->block; 1267 } 1268 1269 static int 1270 hfsc_dump_sc(struct sk_buff *skb, int attr, struct internal_sc *sc) 1271 { 1272 struct tc_service_curve tsc; 1273 1274 tsc.m1 = sm2m(sc->sm1); 1275 tsc.d = dx2d(sc->dx); 1276 tsc.m2 = sm2m(sc->sm2); 1277 if (nla_put(skb, attr, sizeof(tsc), &tsc)) 1278 goto nla_put_failure; 1279 1280 return skb->len; 1281 1282 nla_put_failure: 1283 return -1; 1284 } 1285 1286 static int 1287 hfsc_dump_curves(struct sk_buff *skb, struct hfsc_class *cl) 1288 { 1289 if ((cl->cl_flags & HFSC_RSC) && 1290 (hfsc_dump_sc(skb, TCA_HFSC_RSC, &cl->cl_rsc) < 0)) 1291 goto nla_put_failure; 1292 1293 if ((cl->cl_flags & HFSC_FSC) && 1294 (hfsc_dump_sc(skb, TCA_HFSC_FSC, &cl->cl_fsc) < 0)) 1295 goto nla_put_failure; 1296 1297 if ((cl->cl_flags & HFSC_USC) && 1298 (hfsc_dump_sc(skb, TCA_HFSC_USC, &cl->cl_usc) < 0)) 1299 goto nla_put_failure; 1300 1301 return skb->len; 1302 1303 nla_put_failure: 1304 return -1; 1305 } 1306 1307 static int 1308 hfsc_dump_class(struct Qdisc *sch, unsigned long arg, struct sk_buff *skb, 1309 struct tcmsg *tcm) 1310 { 1311 struct hfsc_class *cl = (struct hfsc_class *)arg; 1312 struct nlattr *nest; 1313 1314 tcm->tcm_parent = cl->cl_parent ? cl->cl_parent->cl_common.classid : 1315 TC_H_ROOT; 1316 tcm->tcm_handle = cl->cl_common.classid; 1317 if (cl->level == 0) 1318 tcm->tcm_info = cl->qdisc->handle; 1319 1320 nest = nla_nest_start_noflag(skb, TCA_OPTIONS); 1321 if (nest == NULL) 1322 goto nla_put_failure; 1323 if (hfsc_dump_curves(skb, cl) < 0) 1324 goto nla_put_failure; 1325 return nla_nest_end(skb, nest); 1326 1327 nla_put_failure: 1328 nla_nest_cancel(skb, nest); 1329 return -EMSGSIZE; 1330 } 1331 1332 static int 1333 hfsc_dump_class_stats(struct Qdisc *sch, unsigned long arg, 1334 struct gnet_dump *d) 1335 { 1336 struct hfsc_class *cl = (struct hfsc_class *)arg; 1337 struct tc_hfsc_stats xstats; 1338 __u32 qlen; 1339 1340 qdisc_qstats_qlen_backlog(cl->qdisc, &qlen, &cl->qstats.backlog); 1341 xstats.level = cl->level; 1342 xstats.period = cl->cl_vtperiod; 1343 xstats.work = cl->cl_total; 1344 xstats.rtwork = cl->cl_cumul; 1345 1346 if (gnet_stats_copy_basic(d, NULL, &cl->bstats, true) < 0 || 1347 gnet_stats_copy_rate_est(d, &cl->rate_est) < 0 || 1348 gnet_stats_copy_queue(d, NULL, &cl->qstats, qlen) < 0) 1349 return -1; 1350 1351 return gnet_stats_copy_app(d, &xstats, sizeof(xstats)); 1352 } 1353 1354 1355 1356 static void 1357 hfsc_walk(struct Qdisc *sch, struct qdisc_walker *arg) 1358 { 1359 struct hfsc_sched *q = qdisc_priv(sch); 1360 struct hfsc_class *cl; 1361 unsigned int i; 1362 1363 if (arg->stop) 1364 return; 1365 1366 for (i = 0; i < q->clhash.hashsize; i++) { 1367 hlist_for_each_entry(cl, &q->clhash.hash[i], 1368 cl_common.hnode) { 1369 if (!tc_qdisc_stats_dump(sch, (unsigned long)cl, arg)) 1370 return; 1371 } 1372 } 1373 } 1374 1375 static void 1376 hfsc_schedule_watchdog(struct Qdisc *sch) 1377 { 1378 struct hfsc_sched *q = qdisc_priv(sch); 1379 struct hfsc_class *cl; 1380 u64 next_time = 0; 1381 1382 cl = eltree_get_minel(q); 1383 if (cl) 1384 next_time = cl->cl_e; 1385 if (q->root.cl_cfmin != 0) { 1386 if (next_time == 0 || next_time > q->root.cl_cfmin) 1387 next_time = q->root.cl_cfmin; 1388 } 1389 if (next_time) 1390 qdisc_watchdog_schedule(&q->watchdog, next_time); 1391 } 1392 1393 static int 1394 hfsc_init_qdisc(struct Qdisc *sch, struct nlattr *opt, 1395 struct netlink_ext_ack *extack) 1396 { 1397 struct hfsc_sched *q = qdisc_priv(sch); 1398 struct tc_hfsc_qopt *qopt; 1399 int err; 1400 1401 qdisc_watchdog_init(&q->watchdog, sch); 1402 1403 if (!opt || nla_len(opt) < sizeof(*qopt)) 1404 return -EINVAL; 1405 qopt = nla_data(opt); 1406 1407 q->defcls = qopt->defcls; 1408 err = qdisc_class_hash_init(&q->clhash); 1409 if (err < 0) 1410 return err; 1411 q->eligible = RB_ROOT; 1412 1413 err = tcf_block_get(&q->root.block, &q->root.filter_list, sch, extack); 1414 if (err) 1415 return err; 1416 1417 gnet_stats_basic_sync_init(&q->root.bstats); 1418 q->root.cl_common.classid = sch->handle; 1419 q->root.sched = q; 1420 q->root.qdisc = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops, 1421 sch->handle, NULL); 1422 if (q->root.qdisc == NULL) 1423 q->root.qdisc = &noop_qdisc; 1424 else 1425 qdisc_hash_add(q->root.qdisc, true); 1426 INIT_LIST_HEAD(&q->root.children); 1427 q->root.vt_tree = RB_ROOT; 1428 q->root.cf_tree = RB_ROOT; 1429 1430 qdisc_class_hash_insert(&q->clhash, &q->root.cl_common); 1431 qdisc_class_hash_grow(sch, &q->clhash); 1432 1433 return 0; 1434 } 1435 1436 static int 1437 hfsc_change_qdisc(struct Qdisc *sch, struct nlattr *opt, 1438 struct netlink_ext_ack *extack) 1439 { 1440 struct hfsc_sched *q = qdisc_priv(sch); 1441 struct tc_hfsc_qopt *qopt; 1442 1443 if (nla_len(opt) < sizeof(*qopt)) 1444 return -EINVAL; 1445 qopt = nla_data(opt); 1446 1447 WRITE_ONCE(q->defcls, qopt->defcls); 1448 1449 return 0; 1450 } 1451 1452 static void 1453 hfsc_reset_class(struct hfsc_class *cl) 1454 { 1455 cl->cl_total = 0; 1456 cl->cl_cumul = 0; 1457 cl->cl_d = 0; 1458 cl->cl_e = 0; 1459 cl->cl_vt = 0; 1460 cl->cl_vtadj = 0; 1461 cl->cl_cvtmin = 0; 1462 cl->cl_cvtoff = 0; 1463 cl->cl_vtperiod = 0; 1464 cl->cl_parentperiod = 0; 1465 cl->cl_f = 0; 1466 cl->cl_myf = 0; 1467 cl->cl_cfmin = 0; 1468 cl->cl_nactive = 0; 1469 1470 cl->vt_tree = RB_ROOT; 1471 cl->cf_tree = RB_ROOT; 1472 qdisc_reset(cl->qdisc); 1473 1474 if (cl->cl_flags & HFSC_RSC) 1475 rtsc_init(&cl->cl_deadline, &cl->cl_rsc, 0, 0); 1476 if (cl->cl_flags & HFSC_FSC) 1477 rtsc_init(&cl->cl_virtual, &cl->cl_fsc, 0, 0); 1478 if (cl->cl_flags & HFSC_USC) 1479 rtsc_init(&cl->cl_ulimit, &cl->cl_usc, 0, 0); 1480 } 1481 1482 static void 1483 hfsc_reset_qdisc(struct Qdisc *sch) 1484 { 1485 struct hfsc_sched *q = qdisc_priv(sch); 1486 struct hfsc_class *cl; 1487 unsigned int i; 1488 1489 for (i = 0; i < q->clhash.hashsize; i++) { 1490 hlist_for_each_entry(cl, &q->clhash.hash[i], cl_common.hnode) 1491 hfsc_reset_class(cl); 1492 } 1493 q->eligible = RB_ROOT; 1494 qdisc_watchdog_cancel(&q->watchdog); 1495 } 1496 1497 static void 1498 hfsc_destroy_qdisc(struct Qdisc *sch) 1499 { 1500 struct hfsc_sched *q = qdisc_priv(sch); 1501 struct hlist_node *next; 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 tcf_block_put(cl->block); 1508 cl->block = NULL; 1509 } 1510 } 1511 for (i = 0; i < q->clhash.hashsize; i++) { 1512 hlist_for_each_entry_safe(cl, next, &q->clhash.hash[i], 1513 cl_common.hnode) 1514 hfsc_destroy_class(sch, cl); 1515 } 1516 qdisc_class_hash_destroy(&q->clhash); 1517 qdisc_watchdog_cancel(&q->watchdog); 1518 } 1519 1520 static int 1521 hfsc_dump_qdisc(struct Qdisc *sch, struct sk_buff *skb) 1522 { 1523 struct hfsc_sched *q = qdisc_priv(sch); 1524 unsigned char *b = skb_tail_pointer(skb); 1525 struct tc_hfsc_qopt qopt; 1526 1527 qopt.defcls = READ_ONCE(q->defcls); 1528 if (nla_put(skb, TCA_OPTIONS, sizeof(qopt), &qopt)) 1529 goto nla_put_failure; 1530 return skb->len; 1531 1532 nla_put_failure: 1533 nlmsg_trim(skb, b); 1534 return -1; 1535 } 1536 1537 static int 1538 hfsc_enqueue(struct sk_buff *skb, struct Qdisc *sch, struct sk_buff **to_free) 1539 { 1540 unsigned int len = qdisc_pkt_len(skb); 1541 struct hfsc_class *cl; 1542 int err; 1543 bool first; 1544 1545 cl = hfsc_classify(skb, sch, &err); 1546 if (cl == NULL) { 1547 if (err & __NET_XMIT_BYPASS) 1548 qdisc_qstats_drop(sch); 1549 __qdisc_drop(skb, to_free); 1550 return err; 1551 } 1552 1553 first = !cl->qdisc->q.qlen; 1554 err = qdisc_enqueue(skb, cl->qdisc, to_free); 1555 if (unlikely(err != NET_XMIT_SUCCESS)) { 1556 if (net_xmit_drop_count(err)) { 1557 cl->qstats.drops++; 1558 qdisc_qstats_drop(sch); 1559 } 1560 return err; 1561 } 1562 1563 sch->qstats.backlog += len; 1564 sch->q.qlen++; 1565 1566 if (first && !cl_in_el_or_vttree(cl)) { 1567 if (cl->cl_flags & HFSC_RSC) 1568 init_ed(cl, len); 1569 if (cl->cl_flags & HFSC_FSC) 1570 init_vf(cl, len); 1571 /* 1572 * If this is the first packet, isolate the head so an eventual 1573 * head drop before the first dequeue operation has no chance 1574 * to invalidate the deadline. 1575 */ 1576 if (cl->cl_flags & HFSC_RSC) 1577 cl->qdisc->ops->peek(cl->qdisc); 1578 1579 } 1580 1581 return NET_XMIT_SUCCESS; 1582 } 1583 1584 static struct sk_buff * 1585 hfsc_dequeue(struct Qdisc *sch) 1586 { 1587 struct hfsc_sched *q = qdisc_priv(sch); 1588 struct hfsc_class *cl; 1589 struct sk_buff *skb; 1590 u64 cur_time; 1591 unsigned int next_len; 1592 int realtime = 0; 1593 1594 if (sch->q.qlen == 0) 1595 return NULL; 1596 1597 cur_time = psched_get_time(); 1598 1599 /* 1600 * if there are eligible classes, use real-time criteria. 1601 * find the class with the minimum deadline among 1602 * the eligible classes. 1603 */ 1604 cl = eltree_get_mindl(q, cur_time); 1605 if (cl) { 1606 realtime = 1; 1607 } else { 1608 /* 1609 * use link-sharing criteria 1610 * get the class with the minimum vt in the hierarchy 1611 */ 1612 cl = vttree_get_minvt(&q->root, cur_time); 1613 if (cl == NULL) { 1614 qdisc_qstats_overlimit(sch); 1615 hfsc_schedule_watchdog(sch); 1616 return NULL; 1617 } 1618 } 1619 1620 skb = qdisc_dequeue_peeked(cl->qdisc); 1621 if (skb == NULL) { 1622 qdisc_warn_nonwc("HFSC", cl->qdisc); 1623 return NULL; 1624 } 1625 1626 bstats_update(&cl->bstats, skb); 1627 update_vf(cl, qdisc_pkt_len(skb), cur_time); 1628 if (realtime) 1629 cl->cl_cumul += qdisc_pkt_len(skb); 1630 1631 if (cl->cl_flags & HFSC_RSC) { 1632 if (cl->qdisc->q.qlen != 0) { 1633 /* update ed */ 1634 next_len = qdisc_peek_len(cl->qdisc); 1635 /* Check queue length again since some qdisc implementations 1636 * (e.g., netem/codel) might empty the queue during the peek 1637 * operation. 1638 */ 1639 if (cl->qdisc->q.qlen != 0) { 1640 if (realtime) 1641 update_ed(cl, next_len); 1642 else 1643 update_d(cl, next_len); 1644 } 1645 } else { 1646 /* the class becomes passive */ 1647 eltree_remove(cl); 1648 } 1649 } 1650 1651 qdisc_bstats_update(sch, skb); 1652 qdisc_qstats_backlog_dec(sch, skb); 1653 sch->q.qlen--; 1654 1655 return skb; 1656 } 1657 1658 static const struct Qdisc_class_ops hfsc_class_ops = { 1659 .change = hfsc_change_class, 1660 .delete = hfsc_delete_class, 1661 .graft = hfsc_graft_class, 1662 .leaf = hfsc_class_leaf, 1663 .qlen_notify = hfsc_qlen_notify, 1664 .find = hfsc_search_class, 1665 .bind_tcf = hfsc_bind_tcf, 1666 .unbind_tcf = hfsc_unbind_tcf, 1667 .tcf_block = hfsc_tcf_block, 1668 .dump = hfsc_dump_class, 1669 .dump_stats = hfsc_dump_class_stats, 1670 .walk = hfsc_walk 1671 }; 1672 1673 static struct Qdisc_ops hfsc_qdisc_ops __read_mostly = { 1674 .id = "hfsc", 1675 .init = hfsc_init_qdisc, 1676 .change = hfsc_change_qdisc, 1677 .reset = hfsc_reset_qdisc, 1678 .destroy = hfsc_destroy_qdisc, 1679 .dump = hfsc_dump_qdisc, 1680 .enqueue = hfsc_enqueue, 1681 .dequeue = hfsc_dequeue, 1682 .peek = qdisc_peek_dequeued, 1683 .cl_ops = &hfsc_class_ops, 1684 .priv_size = sizeof(struct hfsc_sched), 1685 .owner = THIS_MODULE 1686 }; 1687 MODULE_ALIAS_NET_SCH("hfsc"); 1688 1689 static int __init 1690 hfsc_init(void) 1691 { 1692 return register_qdisc(&hfsc_qdisc_ops); 1693 } 1694 1695 static void __exit 1696 hfsc_cleanup(void) 1697 { 1698 unregister_qdisc(&hfsc_qdisc_ops); 1699 } 1700 1701 MODULE_LICENSE("GPL"); 1702 MODULE_DESCRIPTION("Hierarchical Fair Service Curve scheduler"); 1703 module_init(hfsc_init); 1704 module_exit(hfsc_cleanup); 1705