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1 /*
2 * Copyright (c) 2003 Patrick McHardy, <kaber@trash.net>
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version 2
7 * of the License, or (at your option) any later version.
8 *
9 * 2003-10-17 - Ported from altq
10 */
11 /*
12 * Copyright (c) 1997-1999 Carnegie Mellon University. All Rights Reserved.
13 *
14 * Permission to use, copy, modify, and distribute this software and
15 * its documentation is hereby granted (including for commercial or
16 * for-profit use), provided that both the copyright notice and this
17 * permission notice appear in all copies of the software, derivative
18 * works, or modified versions, and any portions thereof.
19 *
20 * THIS SOFTWARE IS EXPERIMENTAL AND IS KNOWN TO HAVE BUGS, SOME OF
21 * WHICH MAY HAVE SERIOUS CONSEQUENCES. CARNEGIE MELLON PROVIDES THIS
22 * SOFTWARE IN ITS ``AS IS'' CONDITION, AND ANY EXPRESS OR IMPLIED
23 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
25 * DISCLAIMED. IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
27 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
28 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
29 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
30 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
31 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
32 * USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
33 * DAMAGE.
34 *
35 * Carnegie Mellon encourages (but does not require) users of this
36 * software to return any improvements or extensions that they make,
37 * and to grant Carnegie Mellon the rights to redistribute these
38 * changes without encumbrance.
39 */
40 /*
41 * H-FSC is described in Proceedings of SIGCOMM'97,
42 * "A Hierarchical Fair Service Curve Algorithm for Link-Sharing,
43 * Real-Time and Priority Service"
44 * by Ion Stoica, Hui Zhang, and T. S. Eugene Ng.
45 *
46 * Oleg Cherevko <olwi@aq.ml.com.ua> added the upperlimit for link-sharing.
47 * when a class has an upperlimit, the fit-time is computed from the
48 * upperlimit service curve. the link-sharing scheduler does not schedule
49 * a class whose fit-time exceeds the current time.
50 */
51
52 #include <linux/kernel.h>
53 #include <linux/module.h>
54 #include <linux/types.h>
55 #include <linux/errno.h>
56 #include <linux/compiler.h>
57 #include <linux/spinlock.h>
58 #include <linux/skbuff.h>
59 #include <linux/string.h>
60 #include <linux/slab.h>
61 #include <linux/list.h>
62 #include <linux/rbtree.h>
63 #include <linux/init.h>
64 #include <linux/rtnetlink.h>
65 #include <linux/pkt_sched.h>
66 #include <net/netlink.h>
67 #include <net/pkt_sched.h>
68 #include <net/pkt_cls.h>
69 #include <asm/div64.h>
70
71 /*
72 * kernel internal service curve representation:
73 * coordinates are given by 64 bit unsigned integers.
74 * x-axis: unit is clock count.
75 * y-axis: unit is byte.
76 *
77 * The service curve parameters are converted to the internal
78 * representation. The slope values are scaled to avoid overflow.
79 * the inverse slope values as well as the y-projection of the 1st
80 * segment are kept in order to 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 unsigned int refcnt; /* usage count */
114
115 struct gnet_stats_basic_packed bstats;
116 struct gnet_stats_queue qstats;
117 struct gnet_stats_rate_est64 rate_est;
118 unsigned int level; /* class level in hierarchy */
119 struct tcf_proto __rcu *filter_list; /* filter list */
120 unsigned int filter_cnt; /* filter count */
121
122 struct hfsc_sched *sched; /* scheduler data */
123 struct hfsc_class *cl_parent; /* parent class */
124 struct list_head siblings; /* sibling classes */
125 struct list_head children; /* child classes */
126 struct Qdisc *qdisc; /* leaf qdisc */
127
128 struct rb_node el_node; /* qdisc's eligible tree member */
129 struct rb_root vt_tree; /* active children sorted by cl_vt */
130 struct rb_node vt_node; /* parent's vt_tree member */
131 struct rb_root cf_tree; /* active children sorted by cl_f */
132 struct rb_node cf_node; /* parent's cf_heap member */
133 struct list_head dlist; /* drop list member */
134
135 u64 cl_total; /* total work in bytes */
136 u64 cl_cumul; /* cumulative work in bytes done by
137 real-time criteria */
138
139 u64 cl_d; /* deadline*/
140 u64 cl_e; /* eligible time */
141 u64 cl_vt; /* virtual time */
142 u64 cl_f; /* time when this class will fit for
143 link-sharing, max(myf, cfmin) */
144 u64 cl_myf; /* my fit-time (calculated from this
145 class's own upperlimit curve) */
146 u64 cl_myfadj; /* my fit-time adjustment (to cancel
147 history dependence) */
148 u64 cl_cfmin; /* earliest children's fit-time (used
149 with cl_myf to obtain cl_f) */
150 u64 cl_cvtmin; /* minimal virtual time among the
151 children fit for link-sharing
152 (monotonic within a period) */
153 u64 cl_vtadj; /* intra-period cumulative vt
154 adjustment */
155 u64 cl_vtoff; /* inter-period cumulative vt offset */
156 u64 cl_cvtmax; /* max child's vt in the last period */
157 u64 cl_cvtoff; /* cumulative cvtmax of all periods */
158 u64 cl_pcvtoff; /* parent's cvtoff at initialization
159 time */
160
161 struct internal_sc cl_rsc; /* internal real-time service curve */
162 struct internal_sc cl_fsc; /* internal fair service curve */
163 struct internal_sc cl_usc; /* internal upperlimit service curve */
164 struct runtime_sc cl_deadline; /* deadline curve */
165 struct runtime_sc cl_eligible; /* eligible curve */
166 struct runtime_sc cl_virtual; /* virtual curve */
167 struct runtime_sc cl_ulimit; /* upperlimit curve */
168
169 unsigned long cl_flags; /* which curves are valid */
170 unsigned long cl_vtperiod; /* vt period sequence number */
171 unsigned long cl_parentperiod;/* parent's vt period sequence number*/
172 unsigned long cl_nactive; /* number of active children */
173 };
174
175 struct hfsc_sched {
176 u16 defcls; /* default class id */
177 struct hfsc_class root; /* root class */
178 struct Qdisc_class_hash clhash; /* class hash */
179 struct rb_root eligible; /* eligible tree */
180 struct list_head droplist; /* active leaf class list (for
181 dropping) */
182 struct qdisc_watchdog watchdog; /* watchdog timer */
183 };
184
185 #define HT_INFINITY 0xffffffffffffffffULL /* infinite time value */
186
187
188 /*
189 * eligible tree holds backlogged classes being sorted by their eligible times.
190 * there is one eligible tree per hfsc instance.
191 */
192
193 static void
194 eltree_insert(struct hfsc_class *cl)
195 {
196 struct rb_node **p = &cl->sched->eligible.rb_node;
197 struct rb_node *parent = NULL;
198 struct hfsc_class *cl1;
199
200 while (*p != NULL) {
201 parent = *p;
202 cl1 = rb_entry(parent, struct hfsc_class, el_node);
203 if (cl->cl_e >= cl1->cl_e)
204 p = &parent->rb_right;
205 else
206 p = &parent->rb_left;
207 }
208 rb_link_node(&cl->el_node, parent, p);
209 rb_insert_color(&cl->el_node, &cl->sched->eligible);
210 }
211
212 static inline void
213 eltree_remove(struct hfsc_class *cl)
214 {
215 rb_erase(&cl->el_node, &cl->sched->eligible);
216 }
217
218 static inline void
219 eltree_update(struct hfsc_class *cl)
220 {
221 eltree_remove(cl);
222 eltree_insert(cl);
223 }
224
225 /* find the class with the minimum deadline among the eligible classes */
226 static inline struct hfsc_class *
227 eltree_get_mindl(struct hfsc_sched *q, u64 cur_time)
228 {
229 struct hfsc_class *p, *cl = NULL;
230 struct rb_node *n;
231
232 for (n = rb_first(&q->eligible); n != NULL; n = rb_next(n)) {
233 p = rb_entry(n, struct hfsc_class, el_node);
234 if (p->cl_e > cur_time)
235 break;
236 if (cl == NULL || p->cl_d < cl->cl_d)
237 cl = p;
238 }
239 return cl;
240 }
241
242 /* find the class with minimum eligible time among the eligible classes */
243 static inline struct hfsc_class *
244 eltree_get_minel(struct hfsc_sched *q)
245 {
246 struct rb_node *n;
247
248 n = rb_first(&q->eligible);
249 if (n == NULL)
250 return NULL;
251 return rb_entry(n, struct hfsc_class, el_node);
252 }
253
254 /*
255 * vttree holds holds backlogged child classes being sorted by their virtual
256 * time. each intermediate class has one vttree.
257 */
258 static void
259 vttree_insert(struct hfsc_class *cl)
260 {
261 struct rb_node **p = &cl->cl_parent->vt_tree.rb_node;
262 struct rb_node *parent = NULL;
263 struct hfsc_class *cl1;
264
265 while (*p != NULL) {
266 parent = *p;
267 cl1 = rb_entry(parent, struct hfsc_class, vt_node);
268 if (cl->cl_vt >= cl1->cl_vt)
269 p = &parent->rb_right;
270 else
271 p = &parent->rb_left;
272 }
273 rb_link_node(&cl->vt_node, parent, p);
274 rb_insert_color(&cl->vt_node, &cl->cl_parent->vt_tree);
275 }
276
277 static inline void
278 vttree_remove(struct hfsc_class *cl)
279 {
280 rb_erase(&cl->vt_node, &cl->cl_parent->vt_tree);
281 }
282
283 static inline void
284 vttree_update(struct hfsc_class *cl)
285 {
286 vttree_remove(cl);
287 vttree_insert(cl);
288 }
289
290 static inline struct hfsc_class *
291 vttree_firstfit(struct hfsc_class *cl, u64 cur_time)
292 {
293 struct hfsc_class *p;
294 struct rb_node *n;
295
296 for (n = rb_first(&cl->vt_tree); n != NULL; n = rb_next(n)) {
297 p = rb_entry(n, struct hfsc_class, vt_node);
298 if (p->cl_f <= cur_time)
299 return p;
300 }
301 return NULL;
302 }
303
304 /*
305 * get the leaf class with the minimum vt in the hierarchy
306 */
307 static struct hfsc_class *
308 vttree_get_minvt(struct hfsc_class *cl, u64 cur_time)
309 {
310 /* if root-class's cfmin is bigger than cur_time nothing to do */
311 if (cl->cl_cfmin > cur_time)
312 return NULL;
313
314 while (cl->level > 0) {
315 cl = vttree_firstfit(cl, cur_time);
316 if (cl == NULL)
317 return NULL;
318 /*
319 * update parent's cl_cvtmin.
320 */
321 if (cl->cl_parent->cl_cvtmin < cl->cl_vt)
322 cl->cl_parent->cl_cvtmin = cl->cl_vt;
323 }
324 return cl;
325 }
326
327 static void
328 cftree_insert(struct hfsc_class *cl)
329 {
330 struct rb_node **p = &cl->cl_parent->cf_tree.rb_node;
331 struct rb_node *parent = NULL;
332 struct hfsc_class *cl1;
333
334 while (*p != NULL) {
335 parent = *p;
336 cl1 = rb_entry(parent, struct hfsc_class, cf_node);
337 if (cl->cl_f >= cl1->cl_f)
338 p = &parent->rb_right;
339 else
340 p = &parent->rb_left;
341 }
342 rb_link_node(&cl->cf_node, parent, p);
343 rb_insert_color(&cl->cf_node, &cl->cl_parent->cf_tree);
344 }
345
346 static inline void
347 cftree_remove(struct hfsc_class *cl)
348 {
349 rb_erase(&cl->cf_node, &cl->cl_parent->cf_tree);
350 }
351
352 static inline void
353 cftree_update(struct hfsc_class *cl)
354 {
355 cftree_remove(cl);
356 cftree_insert(cl);
357 }
358
359 /*
360 * service curve support functions
361 *
362 * external service curve parameters
363 * m: bps
364 * d: us
365 * internal service curve parameters
366 * sm: (bytes/psched_us) << SM_SHIFT
367 * ism: (psched_us/byte) << ISM_SHIFT
368 * dx: psched_us
369 *
370 * The clock source resolution with ktime and PSCHED_SHIFT 10 is 1.024us.
371 *
372 * sm and ism are scaled in order to keep effective digits.
373 * SM_SHIFT and ISM_SHIFT are selected to keep at least 4 effective
374 * digits in decimal using the following table.
375 *
376 * bits/sec 100Kbps 1Mbps 10Mbps 100Mbps 1Gbps
377 * ------------+-------------------------------------------------------
378 * bytes/1.024us 12.8e-3 128e-3 1280e-3 12800e-3 128000e-3
379 *
380 * 1.024us/byte 78.125 7.8125 0.78125 0.078125 0.0078125
381 *
382 * So, for PSCHED_SHIFT 10 we need: SM_SHIFT 20, ISM_SHIFT 18.
383 */
384 #define SM_SHIFT (30 - PSCHED_SHIFT)
385 #define ISM_SHIFT (8 + PSCHED_SHIFT)
386
387 #define SM_MASK ((1ULL << SM_SHIFT) - 1)
388 #define ISM_MASK ((1ULL << ISM_SHIFT) - 1)
389
390 static inline u64
391 seg_x2y(u64 x, u64 sm)
392 {
393 u64 y;
394
395 /*
396 * compute
397 * y = x * sm >> SM_SHIFT
398 * but divide it for the upper and lower bits to avoid overflow
399 */
400 y = (x >> SM_SHIFT) * sm + (((x & SM_MASK) * sm) >> SM_SHIFT);
401 return y;
402 }
403
404 static inline u64
405 seg_y2x(u64 y, u64 ism)
406 {
407 u64 x;
408
409 if (y == 0)
410 x = 0;
411 else if (ism == HT_INFINITY)
412 x = HT_INFINITY;
413 else {
414 x = (y >> ISM_SHIFT) * ism
415 + (((y & ISM_MASK) * ism) >> ISM_SHIFT);
416 }
417 return x;
418 }
419
420 /* Convert m (bps) into sm (bytes/psched us) */
421 static u64
422 m2sm(u32 m)
423 {
424 u64 sm;
425
426 sm = ((u64)m << SM_SHIFT);
427 sm += PSCHED_TICKS_PER_SEC - 1;
428 do_div(sm, PSCHED_TICKS_PER_SEC);
429 return sm;
430 }
431
432 /* convert m (bps) into ism (psched us/byte) */
433 static u64
434 m2ism(u32 m)
435 {
436 u64 ism;
437
438 if (m == 0)
439 ism = HT_INFINITY;
440 else {
441 ism = ((u64)PSCHED_TICKS_PER_SEC << ISM_SHIFT);
442 ism += m - 1;
443 do_div(ism, m);
444 }
445 return ism;
446 }
447
448 /* convert d (us) into dx (psched us) */
449 static u64
450 d2dx(u32 d)
451 {
452 u64 dx;
453
454 dx = ((u64)d * PSCHED_TICKS_PER_SEC);
455 dx += USEC_PER_SEC - 1;
456 do_div(dx, USEC_PER_SEC);
457 return dx;
458 }
459
460 /* convert sm (bytes/psched us) into m (bps) */
461 static u32
462 sm2m(u64 sm)
463 {
464 u64 m;
465
466 m = (sm * PSCHED_TICKS_PER_SEC) >> SM_SHIFT;
467 return (u32)m;
468 }
469
470 /* convert dx (psched us) into d (us) */
471 static u32
472 dx2d(u64 dx)
473 {
474 u64 d;
475
476 d = dx * USEC_PER_SEC;
477 do_div(d, PSCHED_TICKS_PER_SEC);
478 return (u32)d;
479 }
480
481 static void
482 sc2isc(struct tc_service_curve *sc, struct internal_sc *isc)
483 {
484 isc->sm1 = m2sm(sc->m1);
485 isc->ism1 = m2ism(sc->m1);
486 isc->dx = d2dx(sc->d);
487 isc->dy = seg_x2y(isc->dx, isc->sm1);
488 isc->sm2 = m2sm(sc->m2);
489 isc->ism2 = m2ism(sc->m2);
490 }
491
492 /*
493 * initialize the runtime service curve with the given internal
494 * service curve starting at (x, y).
495 */
496 static void
497 rtsc_init(struct runtime_sc *rtsc, struct internal_sc *isc, u64 x, u64 y)
498 {
499 rtsc->x = x;
500 rtsc->y = y;
501 rtsc->sm1 = isc->sm1;
502 rtsc->ism1 = isc->ism1;
503 rtsc->dx = isc->dx;
504 rtsc->dy = isc->dy;
505 rtsc->sm2 = isc->sm2;
506 rtsc->ism2 = isc->ism2;
507 }
508
509 /*
510 * calculate the y-projection of the runtime service curve by the
511 * given x-projection value
512 */
513 static u64
514 rtsc_y2x(struct runtime_sc *rtsc, u64 y)
515 {
516 u64 x;
517
518 if (y < rtsc->y)
519 x = rtsc->x;
520 else if (y <= rtsc->y + rtsc->dy) {
521 /* x belongs to the 1st segment */
522 if (rtsc->dy == 0)
523 x = rtsc->x + rtsc->dx;
524 else
525 x = rtsc->x + seg_y2x(y - rtsc->y, rtsc->ism1);
526 } else {
527 /* x belongs to the 2nd segment */
528 x = rtsc->x + rtsc->dx
529 + seg_y2x(y - rtsc->y - rtsc->dy, rtsc->ism2);
530 }
531 return x;
532 }
533
534 static u64
535 rtsc_x2y(struct runtime_sc *rtsc, u64 x)
536 {
537 u64 y;
538
539 if (x <= rtsc->x)
540 y = rtsc->y;
541 else if (x <= rtsc->x + rtsc->dx)
542 /* y belongs to the 1st segment */
543 y = rtsc->y + seg_x2y(x - rtsc->x, rtsc->sm1);
544 else
545 /* y belongs to the 2nd segment */
546 y = rtsc->y + rtsc->dy
547 + seg_x2y(x - rtsc->x - rtsc->dx, rtsc->sm2);
548 return y;
549 }
550
551 /*
552 * update the runtime service curve by taking the minimum of the current
553 * runtime service curve and the service curve starting at (x, y).
554 */
555 static void
556 rtsc_min(struct runtime_sc *rtsc, struct internal_sc *isc, u64 x, u64 y)
557 {
558 u64 y1, y2, dx, dy;
559 u32 dsm;
560
561 if (isc->sm1 <= isc->sm2) {
562 /* service curve is convex */
563 y1 = rtsc_x2y(rtsc, x);
564 if (y1 < y)
565 /* the current rtsc is smaller */
566 return;
567 rtsc->x = x;
568 rtsc->y = y;
569 return;
570 }
571
572 /*
573 * service curve is concave
574 * compute the two y values of the current rtsc
575 * y1: at x
576 * y2: at (x + dx)
577 */
578 y1 = rtsc_x2y(rtsc, x);
579 if (y1 <= y) {
580 /* rtsc is below isc, no change to rtsc */
581 return;
582 }
583
584 y2 = rtsc_x2y(rtsc, x + isc->dx);
585 if (y2 >= y + isc->dy) {
586 /* rtsc is above isc, replace rtsc by isc */
587 rtsc->x = x;
588 rtsc->y = y;
589 rtsc->dx = isc->dx;
590 rtsc->dy = isc->dy;
591 return;
592 }
593
594 /*
595 * the two curves intersect
596 * compute the offsets (dx, dy) using the reverse
597 * function of seg_x2y()
598 * seg_x2y(dx, sm1) == seg_x2y(dx, sm2) + (y1 - y)
599 */
600 dx = (y1 - y) << SM_SHIFT;
601 dsm = isc->sm1 - isc->sm2;
602 do_div(dx, dsm);
603 /*
604 * check if (x, y1) belongs to the 1st segment of rtsc.
605 * if so, add the offset.
606 */
607 if (rtsc->x + rtsc->dx > x)
608 dx += rtsc->x + rtsc->dx - x;
609 dy = seg_x2y(dx, isc->sm1);
610
611 rtsc->x = x;
612 rtsc->y = y;
613 rtsc->dx = dx;
614 rtsc->dy = dy;
615 }
616
617 static void
618 init_ed(struct hfsc_class *cl, unsigned int next_len)
619 {
620 u64 cur_time = psched_get_time();
621
622 /* update the deadline curve */
623 rtsc_min(&cl->cl_deadline, &cl->cl_rsc, cur_time, cl->cl_cumul);
624
625 /*
626 * update the eligible curve.
627 * for concave, it is equal to the deadline curve.
628 * for convex, it is a linear curve with slope m2.
629 */
630 cl->cl_eligible = cl->cl_deadline;
631 if (cl->cl_rsc.sm1 <= cl->cl_rsc.sm2) {
632 cl->cl_eligible.dx = 0;
633 cl->cl_eligible.dy = 0;
634 }
635
636 /* compute e and d */
637 cl->cl_e = rtsc_y2x(&cl->cl_eligible, cl->cl_cumul);
638 cl->cl_d = rtsc_y2x(&cl->cl_deadline, cl->cl_cumul + next_len);
639
640 eltree_insert(cl);
641 }
642
643 static void
644 update_ed(struct hfsc_class *cl, unsigned int next_len)
645 {
646 cl->cl_e = rtsc_y2x(&cl->cl_eligible, cl->cl_cumul);
647 cl->cl_d = rtsc_y2x(&cl->cl_deadline, cl->cl_cumul + next_len);
648
649 eltree_update(cl);
650 }
651
652 static inline void
653 update_d(struct hfsc_class *cl, unsigned int next_len)
654 {
655 cl->cl_d = rtsc_y2x(&cl->cl_deadline, cl->cl_cumul + next_len);
656 }
657
658 static inline void
659 update_cfmin(struct hfsc_class *cl)
660 {
661 struct rb_node *n = rb_first(&cl->cf_tree);
662 struct hfsc_class *p;
663
664 if (n == NULL) {
665 cl->cl_cfmin = 0;
666 return;
667 }
668 p = rb_entry(n, struct hfsc_class, cf_node);
669 cl->cl_cfmin = p->cl_f;
670 }
671
672 static void
673 init_vf(struct hfsc_class *cl, unsigned int len)
674 {
675 struct hfsc_class *max_cl;
676 struct rb_node *n;
677 u64 vt, f, cur_time;
678 int go_active;
679
680 cur_time = 0;
681 go_active = 1;
682 for (; cl->cl_parent != NULL; cl = cl->cl_parent) {
683 if (go_active && cl->cl_nactive++ == 0)
684 go_active = 1;
685 else
686 go_active = 0;
687
688 if (go_active) {
689 n = rb_last(&cl->cl_parent->vt_tree);
690 if (n != NULL) {
691 max_cl = rb_entry(n, struct hfsc_class, vt_node);
692 /*
693 * set vt to the average of the min and max
694 * classes. if the parent's period didn't
695 * change, don't decrease vt of the class.
696 */
697 vt = max_cl->cl_vt;
698 if (cl->cl_parent->cl_cvtmin != 0)
699 vt = (cl->cl_parent->cl_cvtmin + vt)/2;
700
701 if (cl->cl_parent->cl_vtperiod !=
702 cl->cl_parentperiod || vt > cl->cl_vt)
703 cl->cl_vt = vt;
704 } else {
705 /*
706 * first child for a new parent backlog period.
707 * add parent's cvtmax to cvtoff to make a new
708 * vt (vtoff + vt) larger than the vt in the
709 * last period for all children.
710 */
711 vt = cl->cl_parent->cl_cvtmax;
712 cl->cl_parent->cl_cvtoff += vt;
713 cl->cl_parent->cl_cvtmax = 0;
714 cl->cl_parent->cl_cvtmin = 0;
715 cl->cl_vt = 0;
716 }
717
718 cl->cl_vtoff = cl->cl_parent->cl_cvtoff -
719 cl->cl_pcvtoff;
720
721 /* update the virtual curve */
722 vt = cl->cl_vt + cl->cl_vtoff;
723 rtsc_min(&cl->cl_virtual, &cl->cl_fsc, vt,
724 cl->cl_total);
725 if (cl->cl_virtual.x == vt) {
726 cl->cl_virtual.x -= cl->cl_vtoff;
727 cl->cl_vtoff = 0;
728 }
729 cl->cl_vtadj = 0;
730
731 cl->cl_vtperiod++; /* increment vt period */
732 cl->cl_parentperiod = cl->cl_parent->cl_vtperiod;
733 if (cl->cl_parent->cl_nactive == 0)
734 cl->cl_parentperiod++;
735 cl->cl_f = 0;
736
737 vttree_insert(cl);
738 cftree_insert(cl);
739
740 if (cl->cl_flags & HFSC_USC) {
741 /* class has upper limit curve */
742 if (cur_time == 0)
743 cur_time = psched_get_time();
744
745 /* update the ulimit curve */
746 rtsc_min(&cl->cl_ulimit, &cl->cl_usc, cur_time,
747 cl->cl_total);
748 /* compute myf */
749 cl->cl_myf = rtsc_y2x(&cl->cl_ulimit,
750 cl->cl_total);
751 cl->cl_myfadj = 0;
752 }
753 }
754
755 f = max(cl->cl_myf, cl->cl_cfmin);
756 if (f != cl->cl_f) {
757 cl->cl_f = f;
758 cftree_update(cl);
759 }
760 update_cfmin(cl->cl_parent);
761 }
762 }
763
764 static void
765 update_vf(struct hfsc_class *cl, unsigned int len, u64 cur_time)
766 {
767 u64 f; /* , myf_bound, delta; */
768 int go_passive = 0;
769
770 if (cl->qdisc->q.qlen == 0 && cl->cl_flags & HFSC_FSC)
771 go_passive = 1;
772
773 for (; cl->cl_parent != NULL; cl = cl->cl_parent) {
774 cl->cl_total += len;
775
776 if (!(cl->cl_flags & HFSC_FSC) || cl->cl_nactive == 0)
777 continue;
778
779 if (go_passive && --cl->cl_nactive == 0)
780 go_passive = 1;
781 else
782 go_passive = 0;
783
784 if (go_passive) {
785 /* no more active child, going passive */
786
787 /* update cvtmax of the parent class */
788 if (cl->cl_vt > cl->cl_parent->cl_cvtmax)
789 cl->cl_parent->cl_cvtmax = cl->cl_vt;
790
791 /* remove this class from the vt tree */
792 vttree_remove(cl);
793
794 cftree_remove(cl);
795 update_cfmin(cl->cl_parent);
796
797 continue;
798 }
799
800 /*
801 * update vt and f
802 */
803 cl->cl_vt = rtsc_y2x(&cl->cl_virtual, cl->cl_total)
804 - cl->cl_vtoff + cl->cl_vtadj;
805
806 /*
807 * if vt of the class is smaller than cvtmin,
808 * the class was skipped in the past due to non-fit.
809 * if so, we need to adjust vtadj.
810 */
811 if (cl->cl_vt < cl->cl_parent->cl_cvtmin) {
812 cl->cl_vtadj += cl->cl_parent->cl_cvtmin - cl->cl_vt;
813 cl->cl_vt = cl->cl_parent->cl_cvtmin;
814 }
815
816 /* update the vt tree */
817 vttree_update(cl);
818
819 if (cl->cl_flags & HFSC_USC) {
820 cl->cl_myf = cl->cl_myfadj + rtsc_y2x(&cl->cl_ulimit,
821 cl->cl_total);
822 #if 0
823 /*
824 * This code causes classes to stay way under their
825 * limit when multiple classes are used at gigabit
826 * speed. needs investigation. -kaber
827 */
828 /*
829 * if myf lags behind by more than one clock tick
830 * from the current time, adjust myfadj to prevent
831 * a rate-limited class from going greedy.
832 * in a steady state under rate-limiting, myf
833 * fluctuates within one clock tick.
834 */
835 myf_bound = cur_time - PSCHED_JIFFIE2US(1);
836 if (cl->cl_myf < myf_bound) {
837 delta = cur_time - cl->cl_myf;
838 cl->cl_myfadj += delta;
839 cl->cl_myf += delta;
840 }
841 #endif
842 }
843
844 f = max(cl->cl_myf, cl->cl_cfmin);
845 if (f != cl->cl_f) {
846 cl->cl_f = f;
847 cftree_update(cl);
848 update_cfmin(cl->cl_parent);
849 }
850 }
851 }
852
853 static void
854 set_active(struct hfsc_class *cl, unsigned int len)
855 {
856 if (cl->cl_flags & HFSC_RSC)
857 init_ed(cl, len);
858 if (cl->cl_flags & HFSC_FSC)
859 init_vf(cl, len);
860
861 list_add_tail(&cl->dlist, &cl->sched->droplist);
862 }
863
864 static void
865 set_passive(struct hfsc_class *cl)
866 {
867 if (cl->cl_flags & HFSC_RSC)
868 eltree_remove(cl);
869
870 list_del(&cl->dlist);
871
872 /*
873 * vttree is now handled in update_vf() so that update_vf(cl, 0, 0)
874 * needs to be called explicitly to remove a class from vttree.
875 */
876 }
877
878 static unsigned int
879 qdisc_peek_len(struct Qdisc *sch)
880 {
881 struct sk_buff *skb;
882 unsigned int len;
883
884 skb = sch->ops->peek(sch);
885 if (skb == NULL) {
886 qdisc_warn_nonwc("qdisc_peek_len", sch);
887 return 0;
888 }
889 len = qdisc_pkt_len(skb);
890
891 return len;
892 }
893
894 static void
895 hfsc_purge_queue(struct Qdisc *sch, struct hfsc_class *cl)
896 {
897 unsigned int len = cl->qdisc->q.qlen;
898
899 qdisc_reset(cl->qdisc);
900 qdisc_tree_decrease_qlen(cl->qdisc, len);
901 }
902
903 static void
904 hfsc_adjust_levels(struct hfsc_class *cl)
905 {
906 struct hfsc_class *p;
907 unsigned int level;
908
909 do {
910 level = 0;
911 list_for_each_entry(p, &cl->children, siblings) {
912 if (p->level >= level)
913 level = p->level + 1;
914 }
915 cl->level = level;
916 } while ((cl = cl->cl_parent) != NULL);
917 }
918
919 static inline struct hfsc_class *
920 hfsc_find_class(u32 classid, struct Qdisc *sch)
921 {
922 struct hfsc_sched *q = qdisc_priv(sch);
923 struct Qdisc_class_common *clc;
924
925 clc = qdisc_class_find(&q->clhash, classid);
926 if (clc == NULL)
927 return NULL;
928 return container_of(clc, struct hfsc_class, cl_common);
929 }
930
931 static void
932 hfsc_change_rsc(struct hfsc_class *cl, struct tc_service_curve *rsc,
933 u64 cur_time)
934 {
935 sc2isc(rsc, &cl->cl_rsc);
936 rtsc_init(&cl->cl_deadline, &cl->cl_rsc, cur_time, cl->cl_cumul);
937 cl->cl_eligible = cl->cl_deadline;
938 if (cl->cl_rsc.sm1 <= cl->cl_rsc.sm2) {
939 cl->cl_eligible.dx = 0;
940 cl->cl_eligible.dy = 0;
941 }
942 cl->cl_flags |= HFSC_RSC;
943 }
944
945 static void
946 hfsc_change_fsc(struct hfsc_class *cl, struct tc_service_curve *fsc)
947 {
948 sc2isc(fsc, &cl->cl_fsc);
949 rtsc_init(&cl->cl_virtual, &cl->cl_fsc, cl->cl_vt, cl->cl_total);
950 cl->cl_flags |= HFSC_FSC;
951 }
952
953 static void
954 hfsc_change_usc(struct hfsc_class *cl, struct tc_service_curve *usc,
955 u64 cur_time)
956 {
957 sc2isc(usc, &cl->cl_usc);
958 rtsc_init(&cl->cl_ulimit, &cl->cl_usc, cur_time, cl->cl_total);
959 cl->cl_flags |= HFSC_USC;
960 }
961
962 static const struct nla_policy hfsc_policy[TCA_HFSC_MAX + 1] = {
963 [TCA_HFSC_RSC] = { .len = sizeof(struct tc_service_curve) },
964 [TCA_HFSC_FSC] = { .len = sizeof(struct tc_service_curve) },
965 [TCA_HFSC_USC] = { .len = sizeof(struct tc_service_curve) },
966 };
967
968 static int
969 hfsc_change_class(struct Qdisc *sch, u32 classid, u32 parentid,
970 struct nlattr **tca, unsigned long *arg)
971 {
972 struct hfsc_sched *q = qdisc_priv(sch);
973 struct hfsc_class *cl = (struct hfsc_class *)*arg;
974 struct hfsc_class *parent = NULL;
975 struct nlattr *opt = tca[TCA_OPTIONS];
976 struct nlattr *tb[TCA_HFSC_MAX + 1];
977 struct tc_service_curve *rsc = NULL, *fsc = NULL, *usc = NULL;
978 u64 cur_time;
979 int err;
980
981 if (opt == NULL)
982 return -EINVAL;
983
984 err = nla_parse_nested(tb, TCA_HFSC_MAX, opt, hfsc_policy);
985 if (err < 0)
986 return err;
987
988 if (tb[TCA_HFSC_RSC]) {
989 rsc = nla_data(tb[TCA_HFSC_RSC]);
990 if (rsc->m1 == 0 && rsc->m2 == 0)
991 rsc = NULL;
992 }
993
994 if (tb[TCA_HFSC_FSC]) {
995 fsc = nla_data(tb[TCA_HFSC_FSC]);
996 if (fsc->m1 == 0 && fsc->m2 == 0)
997 fsc = NULL;
998 }
999
1000 if (tb[TCA_HFSC_USC]) {
1001 usc = nla_data(tb[TCA_HFSC_USC]);
1002 if (usc->m1 == 0 && usc->m2 == 0)
1003 usc = NULL;
1004 }
1005
1006 if (cl != NULL) {
1007 if (parentid) {
1008 if (cl->cl_parent &&
1009 cl->cl_parent->cl_common.classid != parentid)
1010 return -EINVAL;
1011 if (cl->cl_parent == NULL && parentid != TC_H_ROOT)
1012 return -EINVAL;
1013 }
1014 cur_time = psched_get_time();
1015
1016 if (tca[TCA_RATE]) {
1017 spinlock_t *lock = qdisc_root_sleeping_lock(sch);
1018
1019 err = gen_replace_estimator(&cl->bstats, NULL,
1020 &cl->rate_est,
1021 lock,
1022 tca[TCA_RATE]);
1023 if (err)
1024 return err;
1025 }
1026
1027 sch_tree_lock(sch);
1028 if (rsc != NULL)
1029 hfsc_change_rsc(cl, rsc, cur_time);
1030 if (fsc != NULL)
1031 hfsc_change_fsc(cl, fsc);
1032 if (usc != NULL)
1033 hfsc_change_usc(cl, usc, cur_time);
1034
1035 if (cl->qdisc->q.qlen != 0) {
1036 if (cl->cl_flags & HFSC_RSC)
1037 update_ed(cl, qdisc_peek_len(cl->qdisc));
1038 if (cl->cl_flags & HFSC_FSC)
1039 update_vf(cl, 0, cur_time);
1040 }
1041 sch_tree_unlock(sch);
1042
1043 return 0;
1044 }
1045
1046 if (parentid == TC_H_ROOT)
1047 return -EEXIST;
1048
1049 parent = &q->root;
1050 if (parentid) {
1051 parent = hfsc_find_class(parentid, sch);
1052 if (parent == NULL)
1053 return -ENOENT;
1054 }
1055
1056 if (classid == 0 || TC_H_MAJ(classid ^ sch->handle) != 0)
1057 return -EINVAL;
1058 if (hfsc_find_class(classid, sch))
1059 return -EEXIST;
1060
1061 if (rsc == NULL && fsc == NULL)
1062 return -EINVAL;
1063
1064 cl = kzalloc(sizeof(struct hfsc_class), GFP_KERNEL);
1065 if (cl == NULL)
1066 return -ENOBUFS;
1067
1068 if (tca[TCA_RATE]) {
1069 err = gen_new_estimator(&cl->bstats, NULL, &cl->rate_est,
1070 qdisc_root_sleeping_lock(sch),
1071 tca[TCA_RATE]);
1072 if (err) {
1073 kfree(cl);
1074 return err;
1075 }
1076 }
1077
1078 if (rsc != NULL)
1079 hfsc_change_rsc(cl, rsc, 0);
1080 if (fsc != NULL)
1081 hfsc_change_fsc(cl, fsc);
1082 if (usc != NULL)
1083 hfsc_change_usc(cl, usc, 0);
1084
1085 cl->cl_common.classid = classid;
1086 cl->refcnt = 1;
1087 cl->sched = q;
1088 cl->cl_parent = parent;
1089 cl->qdisc = qdisc_create_dflt(sch->dev_queue,
1090 &pfifo_qdisc_ops, classid);
1091 if (cl->qdisc == NULL)
1092 cl->qdisc = &noop_qdisc;
1093 INIT_LIST_HEAD(&cl->children);
1094 cl->vt_tree = RB_ROOT;
1095 cl->cf_tree = RB_ROOT;
1096
1097 sch_tree_lock(sch);
1098 qdisc_class_hash_insert(&q->clhash, &cl->cl_common);
1099 list_add_tail(&cl->siblings, &parent->children);
1100 if (parent->level == 0)
1101 hfsc_purge_queue(sch, parent);
1102 hfsc_adjust_levels(parent);
1103 cl->cl_pcvtoff = parent->cl_cvtoff;
1104 sch_tree_unlock(sch);
1105
1106 qdisc_class_hash_grow(sch, &q->clhash);
1107
1108 *arg = (unsigned long)cl;
1109 return 0;
1110 }
1111
1112 static void
1113 hfsc_destroy_class(struct Qdisc *sch, struct hfsc_class *cl)
1114 {
1115 struct hfsc_sched *q = qdisc_priv(sch);
1116
1117 tcf_destroy_chain(&cl->filter_list);
1118 qdisc_destroy(cl->qdisc);
1119 gen_kill_estimator(&cl->bstats, &cl->rate_est);
1120 if (cl != &q->root)
1121 kfree(cl);
1122 }
1123
1124 static int
1125 hfsc_delete_class(struct Qdisc *sch, unsigned long arg)
1126 {
1127 struct hfsc_sched *q = qdisc_priv(sch);
1128 struct hfsc_class *cl = (struct hfsc_class *)arg;
1129
1130 if (cl->level > 0 || cl->filter_cnt > 0 || cl == &q->root)
1131 return -EBUSY;
1132
1133 sch_tree_lock(sch);
1134
1135 list_del(&cl->siblings);
1136 hfsc_adjust_levels(cl->cl_parent);
1137
1138 hfsc_purge_queue(sch, cl);
1139 qdisc_class_hash_remove(&q->clhash, &cl->cl_common);
1140
1141 BUG_ON(--cl->refcnt == 0);
1142 /*
1143 * This shouldn't happen: we "hold" one cops->get() when called
1144 * from tc_ctl_tclass; the destroy method is done from cops->put().
1145 */
1146
1147 sch_tree_unlock(sch);
1148 return 0;
1149 }
1150
1151 static struct hfsc_class *
1152 hfsc_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr)
1153 {
1154 struct hfsc_sched *q = qdisc_priv(sch);
1155 struct hfsc_class *head, *cl;
1156 struct tcf_result res;
1157 struct tcf_proto *tcf;
1158 int result;
1159
1160 if (TC_H_MAJ(skb->priority ^ sch->handle) == 0 &&
1161 (cl = hfsc_find_class(skb->priority, sch)) != NULL)
1162 if (cl->level == 0)
1163 return cl;
1164
1165 *qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
1166 head = &q->root;
1167 tcf = rcu_dereference_bh(q->root.filter_list);
1168 while (tcf && (result = tc_classify(skb, tcf, &res, false)) >= 0) {
1169 #ifdef CONFIG_NET_CLS_ACT
1170 switch (result) {
1171 case TC_ACT_QUEUED:
1172 case TC_ACT_STOLEN:
1173 *qerr = NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
1174 case TC_ACT_SHOT:
1175 return NULL;
1176 }
1177 #endif
1178 cl = (struct hfsc_class *)res.class;
1179 if (!cl) {
1180 cl = hfsc_find_class(res.classid, sch);
1181 if (!cl)
1182 break; /* filter selected invalid classid */
1183 if (cl->level >= head->level)
1184 break; /* filter may only point downwards */
1185 }
1186
1187 if (cl->level == 0)
1188 return cl; /* hit leaf class */
1189
1190 /* apply inner filter chain */
1191 tcf = rcu_dereference_bh(cl->filter_list);
1192 head = cl;
1193 }
1194
1195 /* classification failed, try default class */
1196 cl = hfsc_find_class(TC_H_MAKE(TC_H_MAJ(sch->handle), q->defcls), sch);
1197 if (cl == NULL || cl->level > 0)
1198 return NULL;
1199
1200 return cl;
1201 }
1202
1203 static int
1204 hfsc_graft_class(struct Qdisc *sch, unsigned long arg, struct Qdisc *new,
1205 struct Qdisc **old)
1206 {
1207 struct hfsc_class *cl = (struct hfsc_class *)arg;
1208
1209 if (cl->level > 0)
1210 return -EINVAL;
1211 if (new == NULL) {
1212 new = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops,
1213 cl->cl_common.classid);
1214 if (new == NULL)
1215 new = &noop_qdisc;
1216 }
1217
1218 sch_tree_lock(sch);
1219 hfsc_purge_queue(sch, cl);
1220 *old = cl->qdisc;
1221 cl->qdisc = new;
1222 sch_tree_unlock(sch);
1223 return 0;
1224 }
1225
1226 static struct Qdisc *
1227 hfsc_class_leaf(struct Qdisc *sch, unsigned long arg)
1228 {
1229 struct hfsc_class *cl = (struct hfsc_class *)arg;
1230
1231 if (cl->level == 0)
1232 return cl->qdisc;
1233
1234 return NULL;
1235 }
1236
1237 static void
1238 hfsc_qlen_notify(struct Qdisc *sch, unsigned long arg)
1239 {
1240 struct hfsc_class *cl = (struct hfsc_class *)arg;
1241
1242 if (cl->qdisc->q.qlen == 0) {
1243 update_vf(cl, 0, 0);
1244 set_passive(cl);
1245 }
1246 }
1247
1248 static unsigned long
1249 hfsc_get_class(struct Qdisc *sch, u32 classid)
1250 {
1251 struct hfsc_class *cl = hfsc_find_class(classid, sch);
1252
1253 if (cl != NULL)
1254 cl->refcnt++;
1255
1256 return (unsigned long)cl;
1257 }
1258
1259 static void
1260 hfsc_put_class(struct Qdisc *sch, unsigned long arg)
1261 {
1262 struct hfsc_class *cl = (struct hfsc_class *)arg;
1263
1264 if (--cl->refcnt == 0)
1265 hfsc_destroy_class(sch, cl);
1266 }
1267
1268 static unsigned long
1269 hfsc_bind_tcf(struct Qdisc *sch, unsigned long parent, u32 classid)
1270 {
1271 struct hfsc_class *p = (struct hfsc_class *)parent;
1272 struct hfsc_class *cl = hfsc_find_class(classid, sch);
1273
1274 if (cl != NULL) {
1275 if (p != NULL && p->level <= cl->level)
1276 return 0;
1277 cl->filter_cnt++;
1278 }
1279
1280 return (unsigned long)cl;
1281 }
1282
1283 static void
1284 hfsc_unbind_tcf(struct Qdisc *sch, unsigned long arg)
1285 {
1286 struct hfsc_class *cl = (struct hfsc_class *)arg;
1287
1288 cl->filter_cnt--;
1289 }
1290
1291 static struct tcf_proto __rcu **
1292 hfsc_tcf_chain(struct Qdisc *sch, unsigned long arg)
1293 {
1294 struct hfsc_sched *q = qdisc_priv(sch);
1295 struct hfsc_class *cl = (struct hfsc_class *)arg;
1296
1297 if (cl == NULL)
1298 cl = &q->root;
1299
1300 return &cl->filter_list;
1301 }
1302
1303 static int
1304 hfsc_dump_sc(struct sk_buff *skb, int attr, struct internal_sc *sc)
1305 {
1306 struct tc_service_curve tsc;
1307
1308 tsc.m1 = sm2m(sc->sm1);
1309 tsc.d = dx2d(sc->dx);
1310 tsc.m2 = sm2m(sc->sm2);
1311 if (nla_put(skb, attr, sizeof(tsc), &tsc))
1312 goto nla_put_failure;
1313
1314 return skb->len;
1315
1316 nla_put_failure:
1317 return -1;
1318 }
1319
1320 static int
1321 hfsc_dump_curves(struct sk_buff *skb, struct hfsc_class *cl)
1322 {
1323 if ((cl->cl_flags & HFSC_RSC) &&
1324 (hfsc_dump_sc(skb, TCA_HFSC_RSC, &cl->cl_rsc) < 0))
1325 goto nla_put_failure;
1326
1327 if ((cl->cl_flags & HFSC_FSC) &&
1328 (hfsc_dump_sc(skb, TCA_HFSC_FSC, &cl->cl_fsc) < 0))
1329 goto nla_put_failure;
1330
1331 if ((cl->cl_flags & HFSC_USC) &&
1332 (hfsc_dump_sc(skb, TCA_HFSC_USC, &cl->cl_usc) < 0))
1333 goto nla_put_failure;
1334
1335 return skb->len;
1336
1337 nla_put_failure:
1338 return -1;
1339 }
1340
1341 static int
1342 hfsc_dump_class(struct Qdisc *sch, unsigned long arg, struct sk_buff *skb,
1343 struct tcmsg *tcm)
1344 {
1345 struct hfsc_class *cl = (struct hfsc_class *)arg;
1346 struct nlattr *nest;
1347
1348 tcm->tcm_parent = cl->cl_parent ? cl->cl_parent->cl_common.classid :
1349 TC_H_ROOT;
1350 tcm->tcm_handle = cl->cl_common.classid;
1351 if (cl->level == 0)
1352 tcm->tcm_info = cl->qdisc->handle;
1353
1354 nest = nla_nest_start(skb, TCA_OPTIONS);
1355 if (nest == NULL)
1356 goto nla_put_failure;
1357 if (hfsc_dump_curves(skb, cl) < 0)
1358 goto nla_put_failure;
1359 return nla_nest_end(skb, nest);
1360
1361 nla_put_failure:
1362 nla_nest_cancel(skb, nest);
1363 return -EMSGSIZE;
1364 }
1365
1366 static int
1367 hfsc_dump_class_stats(struct Qdisc *sch, unsigned long arg,
1368 struct gnet_dump *d)
1369 {
1370 struct hfsc_class *cl = (struct hfsc_class *)arg;
1371 struct tc_hfsc_stats xstats;
1372
1373 cl->qstats.backlog = cl->qdisc->qstats.backlog;
1374 xstats.level = cl->level;
1375 xstats.period = cl->cl_vtperiod;
1376 xstats.work = cl->cl_total;
1377 xstats.rtwork = cl->cl_cumul;
1378
1379 if (gnet_stats_copy_basic(d, NULL, &cl->bstats) < 0 ||
1380 gnet_stats_copy_rate_est(d, &cl->bstats, &cl->rate_est) < 0 ||
1381 gnet_stats_copy_queue(d, NULL, &cl->qstats, cl->qdisc->q.qlen) < 0)
1382 return -1;
1383
1384 return gnet_stats_copy_app(d, &xstats, sizeof(xstats));
1385 }
1386
1387
1388
1389 static void
1390 hfsc_walk(struct Qdisc *sch, struct qdisc_walker *arg)
1391 {
1392 struct hfsc_sched *q = qdisc_priv(sch);
1393 struct hfsc_class *cl;
1394 unsigned int i;
1395
1396 if (arg->stop)
1397 return;
1398
1399 for (i = 0; i < q->clhash.hashsize; i++) {
1400 hlist_for_each_entry(cl, &q->clhash.hash[i],
1401 cl_common.hnode) {
1402 if (arg->count < arg->skip) {
1403 arg->count++;
1404 continue;
1405 }
1406 if (arg->fn(sch, (unsigned long)cl, arg) < 0) {
1407 arg->stop = 1;
1408 return;
1409 }
1410 arg->count++;
1411 }
1412 }
1413 }
1414
1415 static void
1416 hfsc_schedule_watchdog(struct Qdisc *sch)
1417 {
1418 struct hfsc_sched *q = qdisc_priv(sch);
1419 struct hfsc_class *cl;
1420 u64 next_time = 0;
1421
1422 cl = eltree_get_minel(q);
1423 if (cl)
1424 next_time = cl->cl_e;
1425 if (q->root.cl_cfmin != 0) {
1426 if (next_time == 0 || next_time > q->root.cl_cfmin)
1427 next_time = q->root.cl_cfmin;
1428 }
1429 WARN_ON(next_time == 0);
1430 qdisc_watchdog_schedule(&q->watchdog, next_time);
1431 }
1432
1433 static int
1434 hfsc_init_qdisc(struct Qdisc *sch, struct nlattr *opt)
1435 {
1436 struct hfsc_sched *q = qdisc_priv(sch);
1437 struct tc_hfsc_qopt *qopt;
1438 int err;
1439
1440 if (opt == NULL || nla_len(opt) < sizeof(*qopt))
1441 return -EINVAL;
1442 qopt = nla_data(opt);
1443
1444 q->defcls = qopt->defcls;
1445 err = qdisc_class_hash_init(&q->clhash);
1446 if (err < 0)
1447 return err;
1448 q->eligible = RB_ROOT;
1449 INIT_LIST_HEAD(&q->droplist);
1450
1451 q->root.cl_common.classid = sch->handle;
1452 q->root.refcnt = 1;
1453 q->root.sched = q;
1454 q->root.qdisc = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops,
1455 sch->handle);
1456 if (q->root.qdisc == NULL)
1457 q->root.qdisc = &noop_qdisc;
1458 INIT_LIST_HEAD(&q->root.children);
1459 q->root.vt_tree = RB_ROOT;
1460 q->root.cf_tree = RB_ROOT;
1461
1462 qdisc_class_hash_insert(&q->clhash, &q->root.cl_common);
1463 qdisc_class_hash_grow(sch, &q->clhash);
1464
1465 qdisc_watchdog_init(&q->watchdog, sch);
1466
1467 return 0;
1468 }
1469
1470 static int
1471 hfsc_change_qdisc(struct Qdisc *sch, struct nlattr *opt)
1472 {
1473 struct hfsc_sched *q = qdisc_priv(sch);
1474 struct tc_hfsc_qopt *qopt;
1475
1476 if (opt == NULL || nla_len(opt) < sizeof(*qopt))
1477 return -EINVAL;
1478 qopt = nla_data(opt);
1479
1480 sch_tree_lock(sch);
1481 q->defcls = qopt->defcls;
1482 sch_tree_unlock(sch);
1483
1484 return 0;
1485 }
1486
1487 static void
1488 hfsc_reset_class(struct hfsc_class *cl)
1489 {
1490 cl->cl_total = 0;
1491 cl->cl_cumul = 0;
1492 cl->cl_d = 0;
1493 cl->cl_e = 0;
1494 cl->cl_vt = 0;
1495 cl->cl_vtadj = 0;
1496 cl->cl_vtoff = 0;
1497 cl->cl_cvtmin = 0;
1498 cl->cl_cvtmax = 0;
1499 cl->cl_cvtoff = 0;
1500 cl->cl_pcvtoff = 0;
1501 cl->cl_vtperiod = 0;
1502 cl->cl_parentperiod = 0;
1503 cl->cl_f = 0;
1504 cl->cl_myf = 0;
1505 cl->cl_myfadj = 0;
1506 cl->cl_cfmin = 0;
1507 cl->cl_nactive = 0;
1508
1509 cl->vt_tree = RB_ROOT;
1510 cl->cf_tree = RB_ROOT;
1511 qdisc_reset(cl->qdisc);
1512
1513 if (cl->cl_flags & HFSC_RSC)
1514 rtsc_init(&cl->cl_deadline, &cl->cl_rsc, 0, 0);
1515 if (cl->cl_flags & HFSC_FSC)
1516 rtsc_init(&cl->cl_virtual, &cl->cl_fsc, 0, 0);
1517 if (cl->cl_flags & HFSC_USC)
1518 rtsc_init(&cl->cl_ulimit, &cl->cl_usc, 0, 0);
1519 }
1520
1521 static void
1522 hfsc_reset_qdisc(struct Qdisc *sch)
1523 {
1524 struct hfsc_sched *q = qdisc_priv(sch);
1525 struct hfsc_class *cl;
1526 unsigned int i;
1527
1528 for (i = 0; i < q->clhash.hashsize; i++) {
1529 hlist_for_each_entry(cl, &q->clhash.hash[i], cl_common.hnode)
1530 hfsc_reset_class(cl);
1531 }
1532 q->eligible = RB_ROOT;
1533 INIT_LIST_HEAD(&q->droplist);
1534 qdisc_watchdog_cancel(&q->watchdog);
1535 sch->q.qlen = 0;
1536 }
1537
1538 static void
1539 hfsc_destroy_qdisc(struct Qdisc *sch)
1540 {
1541 struct hfsc_sched *q = qdisc_priv(sch);
1542 struct hlist_node *next;
1543 struct hfsc_class *cl;
1544 unsigned int i;
1545
1546 for (i = 0; i < q->clhash.hashsize; i++) {
1547 hlist_for_each_entry(cl, &q->clhash.hash[i], cl_common.hnode)
1548 tcf_destroy_chain(&cl->filter_list);
1549 }
1550 for (i = 0; i < q->clhash.hashsize; i++) {
1551 hlist_for_each_entry_safe(cl, next, &q->clhash.hash[i],
1552 cl_common.hnode)
1553 hfsc_destroy_class(sch, cl);
1554 }
1555 qdisc_class_hash_destroy(&q->clhash);
1556 qdisc_watchdog_cancel(&q->watchdog);
1557 }
1558
1559 static int
1560 hfsc_dump_qdisc(struct Qdisc *sch, struct sk_buff *skb)
1561 {
1562 struct hfsc_sched *q = qdisc_priv(sch);
1563 unsigned char *b = skb_tail_pointer(skb);
1564 struct tc_hfsc_qopt qopt;
1565 struct hfsc_class *cl;
1566 unsigned int i;
1567
1568 sch->qstats.backlog = 0;
1569 for (i = 0; i < q->clhash.hashsize; i++) {
1570 hlist_for_each_entry(cl, &q->clhash.hash[i], cl_common.hnode)
1571 sch->qstats.backlog += cl->qdisc->qstats.backlog;
1572 }
1573
1574 qopt.defcls = q->defcls;
1575 if (nla_put(skb, TCA_OPTIONS, sizeof(qopt), &qopt))
1576 goto nla_put_failure;
1577 return skb->len;
1578
1579 nla_put_failure:
1580 nlmsg_trim(skb, b);
1581 return -1;
1582 }
1583
1584 static int
1585 hfsc_enqueue(struct sk_buff *skb, struct Qdisc *sch)
1586 {
1587 struct hfsc_class *cl;
1588 int uninitialized_var(err);
1589
1590 cl = hfsc_classify(skb, sch, &err);
1591 if (cl == NULL) {
1592 if (err & __NET_XMIT_BYPASS)
1593 qdisc_qstats_drop(sch);
1594 kfree_skb(skb);
1595 return err;
1596 }
1597
1598 err = qdisc_enqueue(skb, cl->qdisc);
1599 if (unlikely(err != NET_XMIT_SUCCESS)) {
1600 if (net_xmit_drop_count(err)) {
1601 cl->qstats.drops++;
1602 qdisc_qstats_drop(sch);
1603 }
1604 return err;
1605 }
1606
1607 if (cl->qdisc->q.qlen == 1)
1608 set_active(cl, qdisc_pkt_len(skb));
1609
1610 sch->q.qlen++;
1611
1612 return NET_XMIT_SUCCESS;
1613 }
1614
1615 static struct sk_buff *
1616 hfsc_dequeue(struct Qdisc *sch)
1617 {
1618 struct hfsc_sched *q = qdisc_priv(sch);
1619 struct hfsc_class *cl;
1620 struct sk_buff *skb;
1621 u64 cur_time;
1622 unsigned int next_len;
1623 int realtime = 0;
1624
1625 if (sch->q.qlen == 0)
1626 return NULL;
1627
1628 cur_time = psched_get_time();
1629
1630 /*
1631 * if there are eligible classes, use real-time criteria.
1632 * find the class with the minimum deadline among
1633 * the eligible classes.
1634 */
1635 cl = eltree_get_mindl(q, cur_time);
1636 if (cl) {
1637 realtime = 1;
1638 } else {
1639 /*
1640 * use link-sharing criteria
1641 * get the class with the minimum vt in the hierarchy
1642 */
1643 cl = vttree_get_minvt(&q->root, cur_time);
1644 if (cl == NULL) {
1645 qdisc_qstats_overlimit(sch);
1646 hfsc_schedule_watchdog(sch);
1647 return NULL;
1648 }
1649 }
1650
1651 skb = qdisc_dequeue_peeked(cl->qdisc);
1652 if (skb == NULL) {
1653 qdisc_warn_nonwc("HFSC", cl->qdisc);
1654 return NULL;
1655 }
1656
1657 bstats_update(&cl->bstats, skb);
1658 update_vf(cl, qdisc_pkt_len(skb), cur_time);
1659 if (realtime)
1660 cl->cl_cumul += qdisc_pkt_len(skb);
1661
1662 if (cl->qdisc->q.qlen != 0) {
1663 if (cl->cl_flags & HFSC_RSC) {
1664 /* update ed */
1665 next_len = qdisc_peek_len(cl->qdisc);
1666 if (realtime)
1667 update_ed(cl, next_len);
1668 else
1669 update_d(cl, next_len);
1670 }
1671 } else {
1672 /* the class becomes passive */
1673 set_passive(cl);
1674 }
1675
1676 qdisc_unthrottled(sch);
1677 qdisc_bstats_update(sch, skb);
1678 sch->q.qlen--;
1679
1680 return skb;
1681 }
1682
1683 static unsigned int
1684 hfsc_drop(struct Qdisc *sch)
1685 {
1686 struct hfsc_sched *q = qdisc_priv(sch);
1687 struct hfsc_class *cl;
1688 unsigned int len;
1689
1690 list_for_each_entry(cl, &q->droplist, dlist) {
1691 if (cl->qdisc->ops->drop != NULL &&
1692 (len = cl->qdisc->ops->drop(cl->qdisc)) > 0) {
1693 if (cl->qdisc->q.qlen == 0) {
1694 update_vf(cl, 0, 0);
1695 set_passive(cl);
1696 } else {
1697 list_move_tail(&cl->dlist, &q->droplist);
1698 }
1699 cl->qstats.drops++;
1700 qdisc_qstats_drop(sch);
1701 sch->q.qlen--;
1702 return len;
1703 }
1704 }
1705 return 0;
1706 }
1707
1708 static const struct Qdisc_class_ops hfsc_class_ops = {
1709 .change = hfsc_change_class,
1710 .delete = hfsc_delete_class,
1711 .graft = hfsc_graft_class,
1712 .leaf = hfsc_class_leaf,
1713 .qlen_notify = hfsc_qlen_notify,
1714 .get = hfsc_get_class,
1715 .put = hfsc_put_class,
1716 .bind_tcf = hfsc_bind_tcf,
1717 .unbind_tcf = hfsc_unbind_tcf,
1718 .tcf_chain = hfsc_tcf_chain,
1719 .dump = hfsc_dump_class,
1720 .dump_stats = hfsc_dump_class_stats,
1721 .walk = hfsc_walk
1722 };
1723
1724 static struct Qdisc_ops hfsc_qdisc_ops __read_mostly = {
1725 .id = "hfsc",
1726 .init = hfsc_init_qdisc,
1727 .change = hfsc_change_qdisc,
1728 .reset = hfsc_reset_qdisc,
1729 .destroy = hfsc_destroy_qdisc,
1730 .dump = hfsc_dump_qdisc,
1731 .enqueue = hfsc_enqueue,
1732 .dequeue = hfsc_dequeue,
1733 .peek = qdisc_peek_dequeued,
1734 .drop = hfsc_drop,
1735 .cl_ops = &hfsc_class_ops,
1736 .priv_size = sizeof(struct hfsc_sched),
1737 .owner = THIS_MODULE
1738 };
1739
1740 static int __init
1741 hfsc_init(void)
1742 {
1743 return register_qdisc(&hfsc_qdisc_ops);
1744 }
1745
1746 static void __exit
1747 hfsc_cleanup(void)
1748 {
1749 unregister_qdisc(&hfsc_qdisc_ops);
1750 }
1751
1752 MODULE_LICENSE("GPL");
1753 module_init(hfsc_init);
1754 module_exit(hfsc_cleanup);