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 void
hfsc_upgrade_rt(struct hfsc_class * cl)907 hfsc_upgrade_rt(struct hfsc_class *cl)
908 {
909 cl->cl_fsc = cl->cl_rsc;
910 rtsc_init(&cl->cl_virtual, &cl->cl_fsc, cl->cl_vt, cl->cl_total);
911 cl->cl_flags |= HFSC_FSC;
912 }
913
914 static const struct nla_policy hfsc_policy[TCA_HFSC_MAX + 1] = {
915 [TCA_HFSC_RSC] = { .len = sizeof(struct tc_service_curve) },
916 [TCA_HFSC_FSC] = { .len = sizeof(struct tc_service_curve) },
917 [TCA_HFSC_USC] = { .len = sizeof(struct tc_service_curve) },
918 };
919
920 static int
hfsc_change_class(struct Qdisc * sch,u32 classid,u32 parentid,struct nlattr ** tca,unsigned long * arg,struct netlink_ext_ack * extack)921 hfsc_change_class(struct Qdisc *sch, u32 classid, u32 parentid,
922 struct nlattr **tca, unsigned long *arg,
923 struct netlink_ext_ack *extack)
924 {
925 struct hfsc_sched *q = qdisc_priv(sch);
926 struct hfsc_class *cl = (struct hfsc_class *)*arg;
927 struct hfsc_class *parent = NULL;
928 struct nlattr *opt = tca[TCA_OPTIONS];
929 struct nlattr *tb[TCA_HFSC_MAX + 1];
930 struct tc_service_curve *rsc = NULL, *fsc = NULL, *usc = NULL;
931 u64 cur_time;
932 int err;
933
934 if (opt == NULL)
935 return -EINVAL;
936
937 err = nla_parse_nested_deprecated(tb, TCA_HFSC_MAX, opt, hfsc_policy,
938 NULL);
939 if (err < 0)
940 return err;
941
942 if (tb[TCA_HFSC_RSC]) {
943 rsc = nla_data(tb[TCA_HFSC_RSC]);
944 if (rsc->m1 == 0 && rsc->m2 == 0)
945 rsc = NULL;
946 }
947
948 if (tb[TCA_HFSC_FSC]) {
949 fsc = nla_data(tb[TCA_HFSC_FSC]);
950 if (fsc->m1 == 0 && fsc->m2 == 0)
951 fsc = NULL;
952 }
953
954 if (tb[TCA_HFSC_USC]) {
955 usc = nla_data(tb[TCA_HFSC_USC]);
956 if (usc->m1 == 0 && usc->m2 == 0)
957 usc = NULL;
958 }
959
960 if (cl != NULL) {
961 int old_flags;
962
963 if (parentid) {
964 if (cl->cl_parent &&
965 cl->cl_parent->cl_common.classid != parentid)
966 return -EINVAL;
967 if (cl->cl_parent == NULL && parentid != TC_H_ROOT)
968 return -EINVAL;
969 }
970 cur_time = psched_get_time();
971
972 if (tca[TCA_RATE]) {
973 err = gen_replace_estimator(&cl->bstats, NULL,
974 &cl->rate_est,
975 NULL,
976 qdisc_root_sleeping_running(sch),
977 tca[TCA_RATE]);
978 if (err)
979 return err;
980 }
981
982 sch_tree_lock(sch);
983 old_flags = cl->cl_flags;
984
985 if (rsc != NULL)
986 hfsc_change_rsc(cl, rsc, cur_time);
987 if (fsc != NULL)
988 hfsc_change_fsc(cl, fsc);
989 if (usc != NULL)
990 hfsc_change_usc(cl, usc, cur_time);
991
992 if (cl->qdisc->q.qlen != 0) {
993 int len = qdisc_peek_len(cl->qdisc);
994
995 if (cl->cl_flags & HFSC_RSC) {
996 if (old_flags & HFSC_RSC)
997 update_ed(cl, len);
998 else
999 init_ed(cl, len);
1000 }
1001
1002 if (cl->cl_flags & HFSC_FSC) {
1003 if (old_flags & HFSC_FSC)
1004 update_vf(cl, 0, cur_time);
1005 else
1006 init_vf(cl, len);
1007 }
1008 }
1009 sch_tree_unlock(sch);
1010
1011 return 0;
1012 }
1013
1014 if (parentid == TC_H_ROOT)
1015 return -EEXIST;
1016
1017 parent = &q->root;
1018 if (parentid) {
1019 parent = hfsc_find_class(parentid, sch);
1020 if (parent == NULL)
1021 return -ENOENT;
1022 }
1023
1024 if (classid == 0 || TC_H_MAJ(classid ^ sch->handle) != 0)
1025 return -EINVAL;
1026 if (hfsc_find_class(classid, sch))
1027 return -EEXIST;
1028
1029 if (rsc == NULL && fsc == NULL)
1030 return -EINVAL;
1031
1032 cl = kzalloc(sizeof(struct hfsc_class), GFP_KERNEL);
1033 if (cl == NULL)
1034 return -ENOBUFS;
1035
1036 err = tcf_block_get(&cl->block, &cl->filter_list, sch, extack);
1037 if (err) {
1038 kfree(cl);
1039 return err;
1040 }
1041
1042 if (tca[TCA_RATE]) {
1043 err = gen_new_estimator(&cl->bstats, NULL, &cl->rate_est,
1044 NULL,
1045 qdisc_root_sleeping_running(sch),
1046 tca[TCA_RATE]);
1047 if (err) {
1048 tcf_block_put(cl->block);
1049 kfree(cl);
1050 return err;
1051 }
1052 }
1053
1054 if (rsc != NULL)
1055 hfsc_change_rsc(cl, rsc, 0);
1056 if (fsc != NULL)
1057 hfsc_change_fsc(cl, fsc);
1058 if (usc != NULL)
1059 hfsc_change_usc(cl, usc, 0);
1060
1061 cl->cl_common.classid = classid;
1062 cl->sched = q;
1063 cl->cl_parent = parent;
1064 cl->qdisc = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops,
1065 classid, NULL);
1066 if (cl->qdisc == NULL)
1067 cl->qdisc = &noop_qdisc;
1068 else
1069 qdisc_hash_add(cl->qdisc, true);
1070 INIT_LIST_HEAD(&cl->children);
1071 cl->vt_tree = RB_ROOT;
1072 cl->cf_tree = RB_ROOT;
1073
1074 sch_tree_lock(sch);
1075 /* Check if the inner class is a misconfigured 'rt' */
1076 if (!(parent->cl_flags & HFSC_FSC) && parent != &q->root) {
1077 NL_SET_ERR_MSG(extack,
1078 "Forced curve change on parent 'rt' to 'sc'");
1079 hfsc_upgrade_rt(parent);
1080 }
1081 qdisc_class_hash_insert(&q->clhash, &cl->cl_common);
1082 list_add_tail(&cl->siblings, &parent->children);
1083 if (parent->level == 0)
1084 qdisc_purge_queue(parent->qdisc);
1085 hfsc_adjust_levels(parent);
1086 sch_tree_unlock(sch);
1087
1088 qdisc_class_hash_grow(sch, &q->clhash);
1089
1090 *arg = (unsigned long)cl;
1091 return 0;
1092 }
1093
1094 static void
hfsc_destroy_class(struct Qdisc * sch,struct hfsc_class * cl)1095 hfsc_destroy_class(struct Qdisc *sch, struct hfsc_class *cl)
1096 {
1097 struct hfsc_sched *q = qdisc_priv(sch);
1098
1099 tcf_block_put(cl->block);
1100 qdisc_put(cl->qdisc);
1101 gen_kill_estimator(&cl->rate_est);
1102 if (cl != &q->root)
1103 kfree(cl);
1104 }
1105
1106 static int
hfsc_delete_class(struct Qdisc * sch,unsigned long arg)1107 hfsc_delete_class(struct Qdisc *sch, unsigned long arg)
1108 {
1109 struct hfsc_sched *q = qdisc_priv(sch);
1110 struct hfsc_class *cl = (struct hfsc_class *)arg;
1111
1112 if (cl->level > 0 || cl->filter_cnt > 0 || cl == &q->root)
1113 return -EBUSY;
1114
1115 sch_tree_lock(sch);
1116
1117 list_del(&cl->siblings);
1118 hfsc_adjust_levels(cl->cl_parent);
1119
1120 qdisc_purge_queue(cl->qdisc);
1121 qdisc_class_hash_remove(&q->clhash, &cl->cl_common);
1122
1123 sch_tree_unlock(sch);
1124
1125 hfsc_destroy_class(sch, cl);
1126 return 0;
1127 }
1128
1129 static struct hfsc_class *
hfsc_classify(struct sk_buff * skb,struct Qdisc * sch,int * qerr)1130 hfsc_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr)
1131 {
1132 struct hfsc_sched *q = qdisc_priv(sch);
1133 struct hfsc_class *head, *cl;
1134 struct tcf_result res;
1135 struct tcf_proto *tcf;
1136 int result;
1137
1138 if (TC_H_MAJ(skb->priority ^ sch->handle) == 0 &&
1139 (cl = hfsc_find_class(skb->priority, sch)) != NULL)
1140 if (cl->level == 0)
1141 return cl;
1142
1143 *qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
1144 head = &q->root;
1145 tcf = rcu_dereference_bh(q->root.filter_list);
1146 while (tcf && (result = tcf_classify(skb, tcf, &res, false)) >= 0) {
1147 #ifdef CONFIG_NET_CLS_ACT
1148 switch (result) {
1149 case TC_ACT_QUEUED:
1150 case TC_ACT_STOLEN:
1151 case TC_ACT_TRAP:
1152 *qerr = NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
1153 /* fall through */
1154 case TC_ACT_SHOT:
1155 return NULL;
1156 }
1157 #endif
1158 cl = (struct hfsc_class *)res.class;
1159 if (!cl) {
1160 cl = hfsc_find_class(res.classid, sch);
1161 if (!cl)
1162 break; /* filter selected invalid classid */
1163 if (cl->level >= head->level)
1164 break; /* filter may only point downwards */
1165 }
1166
1167 if (cl->level == 0)
1168 return cl; /* hit leaf class */
1169
1170 /* apply inner filter chain */
1171 tcf = rcu_dereference_bh(cl->filter_list);
1172 head = cl;
1173 }
1174
1175 /* classification failed, try default class */
1176 cl = hfsc_find_class(TC_H_MAKE(TC_H_MAJ(sch->handle), q->defcls), sch);
1177 if (cl == NULL || cl->level > 0)
1178 return NULL;
1179
1180 return cl;
1181 }
1182
1183 static int
hfsc_graft_class(struct Qdisc * sch,unsigned long arg,struct Qdisc * new,struct Qdisc ** old,struct netlink_ext_ack * extack)1184 hfsc_graft_class(struct Qdisc *sch, unsigned long arg, struct Qdisc *new,
1185 struct Qdisc **old, struct netlink_ext_ack *extack)
1186 {
1187 struct hfsc_class *cl = (struct hfsc_class *)arg;
1188
1189 if (cl->level > 0)
1190 return -EINVAL;
1191 if (new == NULL) {
1192 new = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops,
1193 cl->cl_common.classid, NULL);
1194 if (new == NULL)
1195 new = &noop_qdisc;
1196 }
1197
1198 *old = qdisc_replace(sch, new, &cl->qdisc);
1199 return 0;
1200 }
1201
1202 static struct Qdisc *
hfsc_class_leaf(struct Qdisc * sch,unsigned long arg)1203 hfsc_class_leaf(struct Qdisc *sch, unsigned long arg)
1204 {
1205 struct hfsc_class *cl = (struct hfsc_class *)arg;
1206
1207 if (cl->level == 0)
1208 return cl->qdisc;
1209
1210 return NULL;
1211 }
1212
1213 static void
hfsc_qlen_notify(struct Qdisc * sch,unsigned long arg)1214 hfsc_qlen_notify(struct Qdisc *sch, unsigned long arg)
1215 {
1216 struct hfsc_class *cl = (struct hfsc_class *)arg;
1217
1218 /* vttree is now handled in update_vf() so that update_vf(cl, 0, 0)
1219 * needs to be called explicitly to remove a class from vttree.
1220 */
1221 update_vf(cl, 0, 0);
1222 if (cl->cl_flags & HFSC_RSC)
1223 eltree_remove(cl);
1224 }
1225
1226 static unsigned long
hfsc_search_class(struct Qdisc * sch,u32 classid)1227 hfsc_search_class(struct Qdisc *sch, u32 classid)
1228 {
1229 return (unsigned long)hfsc_find_class(classid, sch);
1230 }
1231
1232 static unsigned long
hfsc_bind_tcf(struct Qdisc * sch,unsigned long parent,u32 classid)1233 hfsc_bind_tcf(struct Qdisc *sch, unsigned long parent, u32 classid)
1234 {
1235 struct hfsc_class *p = (struct hfsc_class *)parent;
1236 struct hfsc_class *cl = hfsc_find_class(classid, sch);
1237
1238 if (cl != NULL) {
1239 if (p != NULL && p->level <= cl->level)
1240 return 0;
1241 cl->filter_cnt++;
1242 }
1243
1244 return (unsigned long)cl;
1245 }
1246
1247 static void
hfsc_unbind_tcf(struct Qdisc * sch,unsigned long arg)1248 hfsc_unbind_tcf(struct Qdisc *sch, unsigned long arg)
1249 {
1250 struct hfsc_class *cl = (struct hfsc_class *)arg;
1251
1252 cl->filter_cnt--;
1253 }
1254
hfsc_tcf_block(struct Qdisc * sch,unsigned long arg,struct netlink_ext_ack * extack)1255 static struct tcf_block *hfsc_tcf_block(struct Qdisc *sch, unsigned long arg,
1256 struct netlink_ext_ack *extack)
1257 {
1258 struct hfsc_sched *q = qdisc_priv(sch);
1259 struct hfsc_class *cl = (struct hfsc_class *)arg;
1260
1261 if (cl == NULL)
1262 cl = &q->root;
1263
1264 return cl->block;
1265 }
1266
1267 static int
hfsc_dump_sc(struct sk_buff * skb,int attr,struct internal_sc * sc)1268 hfsc_dump_sc(struct sk_buff *skb, int attr, struct internal_sc *sc)
1269 {
1270 struct tc_service_curve tsc;
1271
1272 tsc.m1 = sm2m(sc->sm1);
1273 tsc.d = dx2d(sc->dx);
1274 tsc.m2 = sm2m(sc->sm2);
1275 if (nla_put(skb, attr, sizeof(tsc), &tsc))
1276 goto nla_put_failure;
1277
1278 return skb->len;
1279
1280 nla_put_failure:
1281 return -1;
1282 }
1283
1284 static int
hfsc_dump_curves(struct sk_buff * skb,struct hfsc_class * cl)1285 hfsc_dump_curves(struct sk_buff *skb, struct hfsc_class *cl)
1286 {
1287 if ((cl->cl_flags & HFSC_RSC) &&
1288 (hfsc_dump_sc(skb, TCA_HFSC_RSC, &cl->cl_rsc) < 0))
1289 goto nla_put_failure;
1290
1291 if ((cl->cl_flags & HFSC_FSC) &&
1292 (hfsc_dump_sc(skb, TCA_HFSC_FSC, &cl->cl_fsc) < 0))
1293 goto nla_put_failure;
1294
1295 if ((cl->cl_flags & HFSC_USC) &&
1296 (hfsc_dump_sc(skb, TCA_HFSC_USC, &cl->cl_usc) < 0))
1297 goto nla_put_failure;
1298
1299 return skb->len;
1300
1301 nla_put_failure:
1302 return -1;
1303 }
1304
1305 static int
hfsc_dump_class(struct Qdisc * sch,unsigned long arg,struct sk_buff * skb,struct tcmsg * tcm)1306 hfsc_dump_class(struct Qdisc *sch, unsigned long arg, struct sk_buff *skb,
1307 struct tcmsg *tcm)
1308 {
1309 struct hfsc_class *cl = (struct hfsc_class *)arg;
1310 struct nlattr *nest;
1311
1312 tcm->tcm_parent = cl->cl_parent ? cl->cl_parent->cl_common.classid :
1313 TC_H_ROOT;
1314 tcm->tcm_handle = cl->cl_common.classid;
1315 if (cl->level == 0)
1316 tcm->tcm_info = cl->qdisc->handle;
1317
1318 nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
1319 if (nest == NULL)
1320 goto nla_put_failure;
1321 if (hfsc_dump_curves(skb, cl) < 0)
1322 goto nla_put_failure;
1323 return nla_nest_end(skb, nest);
1324
1325 nla_put_failure:
1326 nla_nest_cancel(skb, nest);
1327 return -EMSGSIZE;
1328 }
1329
1330 static int
hfsc_dump_class_stats(struct Qdisc * sch,unsigned long arg,struct gnet_dump * d)1331 hfsc_dump_class_stats(struct Qdisc *sch, unsigned long arg,
1332 struct gnet_dump *d)
1333 {
1334 struct hfsc_class *cl = (struct hfsc_class *)arg;
1335 struct tc_hfsc_stats xstats;
1336 __u32 qlen;
1337
1338 qdisc_qstats_qlen_backlog(cl->qdisc, &qlen, &cl->qstats.backlog);
1339 xstats.level = cl->level;
1340 xstats.period = cl->cl_vtperiod;
1341 xstats.work = cl->cl_total;
1342 xstats.rtwork = cl->cl_cumul;
1343
1344 if (gnet_stats_copy_basic(qdisc_root_sleeping_running(sch), d, NULL, &cl->bstats) < 0 ||
1345 gnet_stats_copy_rate_est(d, &cl->rate_est) < 0 ||
1346 gnet_stats_copy_queue(d, NULL, &cl->qstats, qlen) < 0)
1347 return -1;
1348
1349 return gnet_stats_copy_app(d, &xstats, sizeof(xstats));
1350 }
1351
1352
1353
1354 static void
hfsc_walk(struct Qdisc * sch,struct qdisc_walker * arg)1355 hfsc_walk(struct Qdisc *sch, struct qdisc_walker *arg)
1356 {
1357 struct hfsc_sched *q = qdisc_priv(sch);
1358 struct hfsc_class *cl;
1359 unsigned int i;
1360
1361 if (arg->stop)
1362 return;
1363
1364 for (i = 0; i < q->clhash.hashsize; i++) {
1365 hlist_for_each_entry(cl, &q->clhash.hash[i],
1366 cl_common.hnode) {
1367 if (arg->count < arg->skip) {
1368 arg->count++;
1369 continue;
1370 }
1371 if (arg->fn(sch, (unsigned long)cl, arg) < 0) {
1372 arg->stop = 1;
1373 return;
1374 }
1375 arg->count++;
1376 }
1377 }
1378 }
1379
1380 static void
hfsc_schedule_watchdog(struct Qdisc * sch)1381 hfsc_schedule_watchdog(struct Qdisc *sch)
1382 {
1383 struct hfsc_sched *q = qdisc_priv(sch);
1384 struct hfsc_class *cl;
1385 u64 next_time = 0;
1386
1387 cl = eltree_get_minel(q);
1388 if (cl)
1389 next_time = cl->cl_e;
1390 if (q->root.cl_cfmin != 0) {
1391 if (next_time == 0 || next_time > q->root.cl_cfmin)
1392 next_time = q->root.cl_cfmin;
1393 }
1394 if (next_time)
1395 qdisc_watchdog_schedule(&q->watchdog, next_time);
1396 }
1397
1398 static int
hfsc_init_qdisc(struct Qdisc * sch,struct nlattr * opt,struct netlink_ext_ack * extack)1399 hfsc_init_qdisc(struct Qdisc *sch, struct nlattr *opt,
1400 struct netlink_ext_ack *extack)
1401 {
1402 struct hfsc_sched *q = qdisc_priv(sch);
1403 struct tc_hfsc_qopt *qopt;
1404 int err;
1405
1406 qdisc_watchdog_init(&q->watchdog, sch);
1407
1408 if (!opt || nla_len(opt) < sizeof(*qopt))
1409 return -EINVAL;
1410 qopt = nla_data(opt);
1411
1412 q->defcls = qopt->defcls;
1413 err = qdisc_class_hash_init(&q->clhash);
1414 if (err < 0)
1415 return err;
1416 q->eligible = RB_ROOT;
1417
1418 err = tcf_block_get(&q->root.block, &q->root.filter_list, sch, extack);
1419 if (err)
1420 return err;
1421
1422 q->root.cl_common.classid = sch->handle;
1423 q->root.sched = q;
1424 q->root.qdisc = qdisc_create_dflt(sch->dev_queue, &pfifo_qdisc_ops,
1425 sch->handle, NULL);
1426 if (q->root.qdisc == NULL)
1427 q->root.qdisc = &noop_qdisc;
1428 else
1429 qdisc_hash_add(q->root.qdisc, true);
1430 INIT_LIST_HEAD(&q->root.children);
1431 q->root.vt_tree = RB_ROOT;
1432 q->root.cf_tree = RB_ROOT;
1433
1434 qdisc_class_hash_insert(&q->clhash, &q->root.cl_common);
1435 qdisc_class_hash_grow(sch, &q->clhash);
1436
1437 return 0;
1438 }
1439
1440 static int
hfsc_change_qdisc(struct Qdisc * sch,struct nlattr * opt,struct netlink_ext_ack * extack)1441 hfsc_change_qdisc(struct Qdisc *sch, struct nlattr *opt,
1442 struct netlink_ext_ack *extack)
1443 {
1444 struct hfsc_sched *q = qdisc_priv(sch);
1445 struct tc_hfsc_qopt *qopt;
1446
1447 if (opt == NULL || nla_len(opt) < sizeof(*qopt))
1448 return -EINVAL;
1449 qopt = nla_data(opt);
1450
1451 sch_tree_lock(sch);
1452 q->defcls = qopt->defcls;
1453 sch_tree_unlock(sch);
1454
1455 return 0;
1456 }
1457
1458 static void
hfsc_reset_class(struct hfsc_class * cl)1459 hfsc_reset_class(struct hfsc_class *cl)
1460 {
1461 cl->cl_total = 0;
1462 cl->cl_cumul = 0;
1463 cl->cl_d = 0;
1464 cl->cl_e = 0;
1465 cl->cl_vt = 0;
1466 cl->cl_vtadj = 0;
1467 cl->cl_cvtmin = 0;
1468 cl->cl_cvtoff = 0;
1469 cl->cl_vtperiod = 0;
1470 cl->cl_parentperiod = 0;
1471 cl->cl_f = 0;
1472 cl->cl_myf = 0;
1473 cl->cl_cfmin = 0;
1474 cl->cl_nactive = 0;
1475
1476 cl->vt_tree = RB_ROOT;
1477 cl->cf_tree = RB_ROOT;
1478 qdisc_reset(cl->qdisc);
1479
1480 if (cl->cl_flags & HFSC_RSC)
1481 rtsc_init(&cl->cl_deadline, &cl->cl_rsc, 0, 0);
1482 if (cl->cl_flags & HFSC_FSC)
1483 rtsc_init(&cl->cl_virtual, &cl->cl_fsc, 0, 0);
1484 if (cl->cl_flags & HFSC_USC)
1485 rtsc_init(&cl->cl_ulimit, &cl->cl_usc, 0, 0);
1486 }
1487
1488 static void
hfsc_reset_qdisc(struct Qdisc * sch)1489 hfsc_reset_qdisc(struct Qdisc *sch)
1490 {
1491 struct hfsc_sched *q = qdisc_priv(sch);
1492 struct hfsc_class *cl;
1493 unsigned int i;
1494
1495 for (i = 0; i < q->clhash.hashsize; i++) {
1496 hlist_for_each_entry(cl, &q->clhash.hash[i], cl_common.hnode)
1497 hfsc_reset_class(cl);
1498 }
1499 q->eligible = RB_ROOT;
1500 qdisc_watchdog_cancel(&q->watchdog);
1501 sch->qstats.backlog = 0;
1502 sch->q.qlen = 0;
1503 }
1504
1505 static void
hfsc_destroy_qdisc(struct Qdisc * sch)1506 hfsc_destroy_qdisc(struct Qdisc *sch)
1507 {
1508 struct hfsc_sched *q = qdisc_priv(sch);
1509 struct hlist_node *next;
1510 struct hfsc_class *cl;
1511 unsigned int i;
1512
1513 for (i = 0; i < q->clhash.hashsize; i++) {
1514 hlist_for_each_entry(cl, &q->clhash.hash[i], cl_common.hnode) {
1515 tcf_block_put(cl->block);
1516 cl->block = NULL;
1517 }
1518 }
1519 for (i = 0; i < q->clhash.hashsize; i++) {
1520 hlist_for_each_entry_safe(cl, next, &q->clhash.hash[i],
1521 cl_common.hnode)
1522 hfsc_destroy_class(sch, cl);
1523 }
1524 qdisc_class_hash_destroy(&q->clhash);
1525 qdisc_watchdog_cancel(&q->watchdog);
1526 }
1527
1528 static int
hfsc_dump_qdisc(struct Qdisc * sch,struct sk_buff * skb)1529 hfsc_dump_qdisc(struct Qdisc *sch, struct sk_buff *skb)
1530 {
1531 struct hfsc_sched *q = qdisc_priv(sch);
1532 unsigned char *b = skb_tail_pointer(skb);
1533 struct tc_hfsc_qopt qopt;
1534
1535 qopt.defcls = q->defcls;
1536 if (nla_put(skb, TCA_OPTIONS, sizeof(qopt), &qopt))
1537 goto nla_put_failure;
1538 return skb->len;
1539
1540 nla_put_failure:
1541 nlmsg_trim(skb, b);
1542 return -1;
1543 }
1544
1545 static int
hfsc_enqueue(struct sk_buff * skb,struct Qdisc * sch,struct sk_buff ** to_free)1546 hfsc_enqueue(struct sk_buff *skb, struct Qdisc *sch, struct sk_buff **to_free)
1547 {
1548 unsigned int len = qdisc_pkt_len(skb);
1549 struct hfsc_class *cl;
1550 int err;
1551 bool first;
1552
1553 cl = hfsc_classify(skb, sch, &err);
1554 if (cl == NULL) {
1555 if (err & __NET_XMIT_BYPASS)
1556 qdisc_qstats_drop(sch);
1557 __qdisc_drop(skb, to_free);
1558 return err;
1559 }
1560
1561 first = !cl->qdisc->q.qlen;
1562 err = qdisc_enqueue(skb, cl->qdisc, to_free);
1563 if (unlikely(err != NET_XMIT_SUCCESS)) {
1564 if (net_xmit_drop_count(err)) {
1565 cl->qstats.drops++;
1566 qdisc_qstats_drop(sch);
1567 }
1568 return err;
1569 }
1570
1571 if (first) {
1572 if (cl->cl_flags & HFSC_RSC)
1573 init_ed(cl, len);
1574 if (cl->cl_flags & HFSC_FSC)
1575 init_vf(cl, len);
1576 /*
1577 * If this is the first packet, isolate the head so an eventual
1578 * head drop before the first dequeue operation has no chance
1579 * to invalidate the deadline.
1580 */
1581 if (cl->cl_flags & HFSC_RSC)
1582 cl->qdisc->ops->peek(cl->qdisc);
1583
1584 }
1585
1586 sch->qstats.backlog += len;
1587 sch->q.qlen++;
1588
1589 return NET_XMIT_SUCCESS;
1590 }
1591
1592 static struct sk_buff *
hfsc_dequeue(struct Qdisc * sch)1593 hfsc_dequeue(struct Qdisc *sch)
1594 {
1595 struct hfsc_sched *q = qdisc_priv(sch);
1596 struct hfsc_class *cl;
1597 struct sk_buff *skb;
1598 u64 cur_time;
1599 unsigned int next_len;
1600 int realtime = 0;
1601
1602 if (sch->q.qlen == 0)
1603 return NULL;
1604
1605 cur_time = psched_get_time();
1606
1607 /*
1608 * if there are eligible classes, use real-time criteria.
1609 * find the class with the minimum deadline among
1610 * the eligible classes.
1611 */
1612 cl = eltree_get_mindl(q, cur_time);
1613 if (cl) {
1614 realtime = 1;
1615 } else {
1616 /*
1617 * use link-sharing criteria
1618 * get the class with the minimum vt in the hierarchy
1619 */
1620 cl = vttree_get_minvt(&q->root, cur_time);
1621 if (cl == NULL) {
1622 qdisc_qstats_overlimit(sch);
1623 hfsc_schedule_watchdog(sch);
1624 return NULL;
1625 }
1626 }
1627
1628 skb = qdisc_dequeue_peeked(cl->qdisc);
1629 if (skb == NULL) {
1630 qdisc_warn_nonwc("HFSC", cl->qdisc);
1631 return NULL;
1632 }
1633
1634 bstats_update(&cl->bstats, skb);
1635 update_vf(cl, qdisc_pkt_len(skb), cur_time);
1636 if (realtime)
1637 cl->cl_cumul += qdisc_pkt_len(skb);
1638
1639 if (cl->cl_flags & HFSC_RSC) {
1640 if (cl->qdisc->q.qlen != 0) {
1641 /* update ed */
1642 next_len = qdisc_peek_len(cl->qdisc);
1643 if (realtime)
1644 update_ed(cl, next_len);
1645 else
1646 update_d(cl, next_len);
1647 } else {
1648 /* the class becomes passive */
1649 eltree_remove(cl);
1650 }
1651 }
1652
1653 qdisc_bstats_update(sch, skb);
1654 qdisc_qstats_backlog_dec(sch, skb);
1655 sch->q.qlen--;
1656
1657 return skb;
1658 }
1659
1660 static const struct Qdisc_class_ops hfsc_class_ops = {
1661 .change = hfsc_change_class,
1662 .delete = hfsc_delete_class,
1663 .graft = hfsc_graft_class,
1664 .leaf = hfsc_class_leaf,
1665 .qlen_notify = hfsc_qlen_notify,
1666 .find = hfsc_search_class,
1667 .bind_tcf = hfsc_bind_tcf,
1668 .unbind_tcf = hfsc_unbind_tcf,
1669 .tcf_block = hfsc_tcf_block,
1670 .dump = hfsc_dump_class,
1671 .dump_stats = hfsc_dump_class_stats,
1672 .walk = hfsc_walk
1673 };
1674
1675 static struct Qdisc_ops hfsc_qdisc_ops __read_mostly = {
1676 .id = "hfsc",
1677 .init = hfsc_init_qdisc,
1678 .change = hfsc_change_qdisc,
1679 .reset = hfsc_reset_qdisc,
1680 .destroy = hfsc_destroy_qdisc,
1681 .dump = hfsc_dump_qdisc,
1682 .enqueue = hfsc_enqueue,
1683 .dequeue = hfsc_dequeue,
1684 .peek = qdisc_peek_dequeued,
1685 .cl_ops = &hfsc_class_ops,
1686 .priv_size = sizeof(struct hfsc_sched),
1687 .owner = THIS_MODULE
1688 };
1689
1690 static int __init
hfsc_init(void)1691 hfsc_init(void)
1692 {
1693 return register_qdisc(&hfsc_qdisc_ops);
1694 }
1695
1696 static void __exit
hfsc_cleanup(void)1697 hfsc_cleanup(void)
1698 {
1699 unregister_qdisc(&hfsc_qdisc_ops);
1700 }
1701
1702 MODULE_LICENSE("GPL");
1703 module_init(hfsc_init);
1704 module_exit(hfsc_cleanup);
1705