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