Pull bugzilla-7887 into release branch
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / net / sched / sch_hfsc.c
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/jiffies.h>
57 #include <linux/compiler.h>
58 #include <linux/spinlock.h>
59 #include <linux/skbuff.h>
60 #include <linux/string.h>
61 #include <linux/slab.h>
62 #include <linux/timer.h>
63 #include <linux/list.h>
64 #include <linux/rbtree.h>
65 #include <linux/init.h>
66 #include <linux/netdevice.h>
67 #include <linux/rtnetlink.h>
68 #include <linux/pkt_sched.h>
69 #include <net/pkt_sched.h>
70 #include <net/pkt_cls.h>
71 #include <asm/system.h>
72 #include <asm/div64.h>
73
74 /*
75 * kernel internal service curve representation:
76 * coordinates are given by 64 bit unsigned integers.
77 * x-axis: unit is clock count.
78 * y-axis: unit is byte.
79 *
80 * The service curve parameters are converted to the internal
81 * representation. The slope values are scaled to avoid overflow.
82 * the inverse slope values as well as the y-projection of the 1st
83 * segment are kept in order to to avoid 64-bit divide operations
84 * that are expensive on 32-bit architectures.
85 */
86
87 struct internal_sc
88 {
89 u64 sm1; /* scaled slope of the 1st segment */
90 u64 ism1; /* scaled inverse-slope of the 1st segment */
91 u64 dx; /* the x-projection of the 1st segment */
92 u64 dy; /* the y-projection of the 1st segment */
93 u64 sm2; /* scaled slope of the 2nd segment */
94 u64 ism2; /* scaled inverse-slope of the 2nd segment */
95 };
96
97 /* runtime service curve */
98 struct runtime_sc
99 {
100 u64 x; /* current starting position on x-axis */
101 u64 y; /* current starting position on y-axis */
102 u64 sm1; /* scaled slope of the 1st segment */
103 u64 ism1; /* scaled inverse-slope of the 1st segment */
104 u64 dx; /* the x-projection of the 1st segment */
105 u64 dy; /* the y-projection of the 1st segment */
106 u64 sm2; /* scaled slope of the 2nd segment */
107 u64 ism2; /* scaled inverse-slope of the 2nd segment */
108 };
109
110 enum hfsc_class_flags
111 {
112 HFSC_RSC = 0x1,
113 HFSC_FSC = 0x2,
114 HFSC_USC = 0x4
115 };
116
117 struct hfsc_class
118 {
119 u32 classid; /* class id */
120 unsigned int refcnt; /* usage count */
121
122 struct gnet_stats_basic bstats;
123 struct gnet_stats_queue qstats;
124 struct gnet_stats_rate_est rate_est;
125 spinlock_t *stats_lock;
126 unsigned int level; /* class level in hierarchy */
127 struct tcf_proto *filter_list; /* filter list */
128 unsigned int filter_cnt; /* filter count */
129
130 struct hfsc_sched *sched; /* scheduler data */
131 struct hfsc_class *cl_parent; /* parent class */
132 struct list_head siblings; /* sibling classes */
133 struct list_head children; /* child classes */
134 struct Qdisc *qdisc; /* leaf qdisc */
135
136 struct rb_node el_node; /* qdisc's eligible tree member */
137 struct rb_root vt_tree; /* active children sorted by cl_vt */
138 struct rb_node vt_node; /* parent's vt_tree member */
139 struct rb_root cf_tree; /* active children sorted by cl_f */
140 struct rb_node cf_node; /* parent's cf_heap member */
141 struct list_head hlist; /* hash list member */
142 struct list_head dlist; /* drop list member */
143
144 u64 cl_total; /* total work in bytes */
145 u64 cl_cumul; /* cumulative work in bytes done by
146 real-time criteria */
147
148 u64 cl_d; /* deadline*/
149 u64 cl_e; /* eligible time */
150 u64 cl_vt; /* virtual time */
151 u64 cl_f; /* time when this class will fit for
152 link-sharing, max(myf, cfmin) */
153 u64 cl_myf; /* my fit-time (calculated from this
154 class's own upperlimit curve) */
155 u64 cl_myfadj; /* my fit-time adjustment (to cancel
156 history dependence) */
157 u64 cl_cfmin; /* earliest children's fit-time (used
158 with cl_myf to obtain cl_f) */
159 u64 cl_cvtmin; /* minimal virtual time among the
160 children fit for link-sharing
161 (monotonic within a period) */
162 u64 cl_vtadj; /* intra-period cumulative vt
163 adjustment */
164 u64 cl_vtoff; /* inter-period cumulative vt offset */
165 u64 cl_cvtmax; /* max child's vt in the last period */
166 u64 cl_cvtoff; /* cumulative cvtmax of all periods */
167 u64 cl_pcvtoff; /* parent's cvtoff at initalization
168 time */
169
170 struct internal_sc cl_rsc; /* internal real-time service curve */
171 struct internal_sc cl_fsc; /* internal fair service curve */
172 struct internal_sc cl_usc; /* internal upperlimit service curve */
173 struct runtime_sc cl_deadline; /* deadline curve */
174 struct runtime_sc cl_eligible; /* eligible curve */
175 struct runtime_sc cl_virtual; /* virtual curve */
176 struct runtime_sc cl_ulimit; /* upperlimit curve */
177
178 unsigned long cl_flags; /* which curves are valid */
179 unsigned long cl_vtperiod; /* vt period sequence number */
180 unsigned long cl_parentperiod;/* parent's vt period sequence number*/
181 unsigned long cl_nactive; /* number of active children */
182 };
183
184 #define HFSC_HSIZE 16
185
186 struct hfsc_sched
187 {
188 u16 defcls; /* default class id */
189 struct hfsc_class root; /* root class */
190 struct list_head clhash[HFSC_HSIZE]; /* class hash */
191 struct rb_root eligible; /* eligible tree */
192 struct list_head droplist; /* active leaf class list (for
193 dropping) */
194 struct sk_buff_head requeue; /* requeued packet */
195 struct timer_list wd_timer; /* watchdog timer */
196 };
197
198 /*
199 * macros
200 */
201 #ifdef CONFIG_NET_SCH_CLK_GETTIMEOFDAY
202 #include <linux/time.h>
203 #undef PSCHED_GET_TIME
204 #define PSCHED_GET_TIME(stamp) \
205 do { \
206 struct timeval tv; \
207 do_gettimeofday(&tv); \
208 (stamp) = 1ULL * USEC_PER_SEC * tv.tv_sec + tv.tv_usec; \
209 } while (0)
210 #endif
211
212 #define HT_INFINITY 0xffffffffffffffffULL /* infinite time value */
213
214
215 /*
216 * eligible tree holds backlogged classes being sorted by their eligible times.
217 * there is one eligible tree per hfsc instance.
218 */
219
220 static void
221 eltree_insert(struct hfsc_class *cl)
222 {
223 struct rb_node **p = &cl->sched->eligible.rb_node;
224 struct rb_node *parent = NULL;
225 struct hfsc_class *cl1;
226
227 while (*p != NULL) {
228 parent = *p;
229 cl1 = rb_entry(parent, struct hfsc_class, el_node);
230 if (cl->cl_e >= cl1->cl_e)
231 p = &parent->rb_right;
232 else
233 p = &parent->rb_left;
234 }
235 rb_link_node(&cl->el_node, parent, p);
236 rb_insert_color(&cl->el_node, &cl->sched->eligible);
237 }
238
239 static inline void
240 eltree_remove(struct hfsc_class *cl)
241 {
242 rb_erase(&cl->el_node, &cl->sched->eligible);
243 }
244
245 static inline void
246 eltree_update(struct hfsc_class *cl)
247 {
248 eltree_remove(cl);
249 eltree_insert(cl);
250 }
251
252 /* find the class with the minimum deadline among the eligible classes */
253 static inline struct hfsc_class *
254 eltree_get_mindl(struct hfsc_sched *q, u64 cur_time)
255 {
256 struct hfsc_class *p, *cl = NULL;
257 struct rb_node *n;
258
259 for (n = rb_first(&q->eligible); n != NULL; n = rb_next(n)) {
260 p = rb_entry(n, struct hfsc_class, el_node);
261 if (p->cl_e > cur_time)
262 break;
263 if (cl == NULL || p->cl_d < cl->cl_d)
264 cl = p;
265 }
266 return cl;
267 }
268
269 /* find the class with minimum eligible time among the eligible classes */
270 static inline struct hfsc_class *
271 eltree_get_minel(struct hfsc_sched *q)
272 {
273 struct rb_node *n;
274
275 n = rb_first(&q->eligible);
276 if (n == NULL)
277 return NULL;
278 return rb_entry(n, struct hfsc_class, el_node);
279 }
280
281 /*
282 * vttree holds holds backlogged child classes being sorted by their virtual
283 * time. each intermediate class has one vttree.
284 */
285 static void
286 vttree_insert(struct hfsc_class *cl)
287 {
288 struct rb_node **p = &cl->cl_parent->vt_tree.rb_node;
289 struct rb_node *parent = NULL;
290 struct hfsc_class *cl1;
291
292 while (*p != NULL) {
293 parent = *p;
294 cl1 = rb_entry(parent, struct hfsc_class, vt_node);
295 if (cl->cl_vt >= cl1->cl_vt)
296 p = &parent->rb_right;
297 else
298 p = &parent->rb_left;
299 }
300 rb_link_node(&cl->vt_node, parent, p);
301 rb_insert_color(&cl->vt_node, &cl->cl_parent->vt_tree);
302 }
303
304 static inline void
305 vttree_remove(struct hfsc_class *cl)
306 {
307 rb_erase(&cl->vt_node, &cl->cl_parent->vt_tree);
308 }
309
310 static inline void
311 vttree_update(struct hfsc_class *cl)
312 {
313 vttree_remove(cl);
314 vttree_insert(cl);
315 }
316
317 static inline struct hfsc_class *
318 vttree_firstfit(struct hfsc_class *cl, u64 cur_time)
319 {
320 struct hfsc_class *p;
321 struct rb_node *n;
322
323 for (n = rb_first(&cl->vt_tree); n != NULL; n = rb_next(n)) {
324 p = rb_entry(n, struct hfsc_class, vt_node);
325 if (p->cl_f <= cur_time)
326 return p;
327 }
328 return NULL;
329 }
330
331 /*
332 * get the leaf class with the minimum vt in the hierarchy
333 */
334 static struct hfsc_class *
335 vttree_get_minvt(struct hfsc_class *cl, u64 cur_time)
336 {
337 /* if root-class's cfmin is bigger than cur_time nothing to do */
338 if (cl->cl_cfmin > cur_time)
339 return NULL;
340
341 while (cl->level > 0) {
342 cl = vttree_firstfit(cl, cur_time);
343 if (cl == NULL)
344 return NULL;
345 /*
346 * update parent's cl_cvtmin.
347 */
348 if (cl->cl_parent->cl_cvtmin < cl->cl_vt)
349 cl->cl_parent->cl_cvtmin = cl->cl_vt;
350 }
351 return cl;
352 }
353
354 static void
355 cftree_insert(struct hfsc_class *cl)
356 {
357 struct rb_node **p = &cl->cl_parent->cf_tree.rb_node;
358 struct rb_node *parent = NULL;
359 struct hfsc_class *cl1;
360
361 while (*p != NULL) {
362 parent = *p;
363 cl1 = rb_entry(parent, struct hfsc_class, cf_node);
364 if (cl->cl_f >= cl1->cl_f)
365 p = &parent->rb_right;
366 else
367 p = &parent->rb_left;
368 }
369 rb_link_node(&cl->cf_node, parent, p);
370 rb_insert_color(&cl->cf_node, &cl->cl_parent->cf_tree);
371 }
372
373 static inline void
374 cftree_remove(struct hfsc_class *cl)
375 {
376 rb_erase(&cl->cf_node, &cl->cl_parent->cf_tree);
377 }
378
379 static inline void
380 cftree_update(struct hfsc_class *cl)
381 {
382 cftree_remove(cl);
383 cftree_insert(cl);
384 }
385
386 /*
387 * service curve support functions
388 *
389 * external service curve parameters
390 * m: bps
391 * d: us
392 * internal service curve parameters
393 * sm: (bytes/psched_us) << SM_SHIFT
394 * ism: (psched_us/byte) << ISM_SHIFT
395 * dx: psched_us
396 *
397 * Clock source resolution (CONFIG_NET_SCH_CLK_*)
398 * JIFFIES: for 48<=HZ<=1534 resolution is between 0.63us and 1.27us.
399 * CPU: resolution is between 0.5us and 1us.
400 * GETTIMEOFDAY: resolution is exactly 1us.
401 *
402 * sm and ism are scaled in order to keep effective digits.
403 * SM_SHIFT and ISM_SHIFT are selected to keep at least 4 effective
404 * digits in decimal using the following table.
405 *
406 * Note: We can afford the additional accuracy (altq hfsc keeps at most
407 * 3 effective digits) thanks to the fact that linux clock is bounded
408 * much more tightly.
409 *
410 * bits/sec 100Kbps 1Mbps 10Mbps 100Mbps 1Gbps
411 * ------------+-------------------------------------------------------
412 * bytes/0.5us 6.25e-3 62.5e-3 625e-3 6250e-e 62500e-3
413 * bytes/us 12.5e-3 125e-3 1250e-3 12500e-3 125000e-3
414 * bytes/1.27us 15.875e-3 158.75e-3 1587.5e-3 15875e-3 158750e-3
415 *
416 * 0.5us/byte 160 16 1.6 0.16 0.016
417 * us/byte 80 8 0.8 0.08 0.008
418 * 1.27us/byte 63 6.3 0.63 0.063 0.0063
419 */
420 #define SM_SHIFT 20
421 #define ISM_SHIFT 18
422
423 #define SM_MASK ((1ULL << SM_SHIFT) - 1)
424 #define ISM_MASK ((1ULL << ISM_SHIFT) - 1)
425
426 static inline u64
427 seg_x2y(u64 x, u64 sm)
428 {
429 u64 y;
430
431 /*
432 * compute
433 * y = x * sm >> SM_SHIFT
434 * but divide it for the upper and lower bits to avoid overflow
435 */
436 y = (x >> SM_SHIFT) * sm + (((x & SM_MASK) * sm) >> SM_SHIFT);
437 return y;
438 }
439
440 static inline u64
441 seg_y2x(u64 y, u64 ism)
442 {
443 u64 x;
444
445 if (y == 0)
446 x = 0;
447 else if (ism == HT_INFINITY)
448 x = HT_INFINITY;
449 else {
450 x = (y >> ISM_SHIFT) * ism
451 + (((y & ISM_MASK) * ism) >> ISM_SHIFT);
452 }
453 return x;
454 }
455
456 /* Convert m (bps) into sm (bytes/psched us) */
457 static u64
458 m2sm(u32 m)
459 {
460 u64 sm;
461
462 sm = ((u64)m << SM_SHIFT);
463 sm += PSCHED_JIFFIE2US(HZ) - 1;
464 do_div(sm, PSCHED_JIFFIE2US(HZ));
465 return sm;
466 }
467
468 /* convert m (bps) into ism (psched us/byte) */
469 static u64
470 m2ism(u32 m)
471 {
472 u64 ism;
473
474 if (m == 0)
475 ism = HT_INFINITY;
476 else {
477 ism = ((u64)PSCHED_JIFFIE2US(HZ) << ISM_SHIFT);
478 ism += m - 1;
479 do_div(ism, m);
480 }
481 return ism;
482 }
483
484 /* convert d (us) into dx (psched us) */
485 static u64
486 d2dx(u32 d)
487 {
488 u64 dx;
489
490 dx = ((u64)d * PSCHED_JIFFIE2US(HZ));
491 dx += USEC_PER_SEC - 1;
492 do_div(dx, USEC_PER_SEC);
493 return dx;
494 }
495
496 /* convert sm (bytes/psched us) into m (bps) */
497 static u32
498 sm2m(u64 sm)
499 {
500 u64 m;
501
502 m = (sm * PSCHED_JIFFIE2US(HZ)) >> SM_SHIFT;
503 return (u32)m;
504 }
505
506 /* convert dx (psched us) into d (us) */
507 static u32
508 dx2d(u64 dx)
509 {
510 u64 d;
511
512 d = dx * USEC_PER_SEC;
513 do_div(d, PSCHED_JIFFIE2US(HZ));
514 return (u32)d;
515 }
516
517 static void
518 sc2isc(struct tc_service_curve *sc, struct internal_sc *isc)
519 {
520 isc->sm1 = m2sm(sc->m1);
521 isc->ism1 = m2ism(sc->m1);
522 isc->dx = d2dx(sc->d);
523 isc->dy = seg_x2y(isc->dx, isc->sm1);
524 isc->sm2 = m2sm(sc->m2);
525 isc->ism2 = m2ism(sc->m2);
526 }
527
528 /*
529 * initialize the runtime service curve with the given internal
530 * service curve starting at (x, y).
531 */
532 static void
533 rtsc_init(struct runtime_sc *rtsc, struct internal_sc *isc, u64 x, u64 y)
534 {
535 rtsc->x = x;
536 rtsc->y = y;
537 rtsc->sm1 = isc->sm1;
538 rtsc->ism1 = isc->ism1;
539 rtsc->dx = isc->dx;
540 rtsc->dy = isc->dy;
541 rtsc->sm2 = isc->sm2;
542 rtsc->ism2 = isc->ism2;
543 }
544
545 /*
546 * calculate the y-projection of the runtime service curve by the
547 * given x-projection value
548 */
549 static u64
550 rtsc_y2x(struct runtime_sc *rtsc, u64 y)
551 {
552 u64 x;
553
554 if (y < rtsc->y)
555 x = rtsc->x;
556 else if (y <= rtsc->y + rtsc->dy) {
557 /* x belongs to the 1st segment */
558 if (rtsc->dy == 0)
559 x = rtsc->x + rtsc->dx;
560 else
561 x = rtsc->x + seg_y2x(y - rtsc->y, rtsc->ism1);
562 } else {
563 /* x belongs to the 2nd segment */
564 x = rtsc->x + rtsc->dx
565 + seg_y2x(y - rtsc->y - rtsc->dy, rtsc->ism2);
566 }
567 return x;
568 }
569
570 static u64
571 rtsc_x2y(struct runtime_sc *rtsc, u64 x)
572 {
573 u64 y;
574
575 if (x <= rtsc->x)
576 y = rtsc->y;
577 else if (x <= rtsc->x + rtsc->dx)
578 /* y belongs to the 1st segment */
579 y = rtsc->y + seg_x2y(x - rtsc->x, rtsc->sm1);
580 else
581 /* y belongs to the 2nd segment */
582 y = rtsc->y + rtsc->dy
583 + seg_x2y(x - rtsc->x - rtsc->dx, rtsc->sm2);
584 return y;
585 }
586
587 /*
588 * update the runtime service curve by taking the minimum of the current
589 * runtime service curve and the service curve starting at (x, y).
590 */
591 static void
592 rtsc_min(struct runtime_sc *rtsc, struct internal_sc *isc, u64 x, u64 y)
593 {
594 u64 y1, y2, dx, dy;
595 u32 dsm;
596
597 if (isc->sm1 <= isc->sm2) {
598 /* service curve is convex */
599 y1 = rtsc_x2y(rtsc, x);
600 if (y1 < y)
601 /* the current rtsc is smaller */
602 return;
603 rtsc->x = x;
604 rtsc->y = y;
605 return;
606 }
607
608 /*
609 * service curve is concave
610 * compute the two y values of the current rtsc
611 * y1: at x
612 * y2: at (x + dx)
613 */
614 y1 = rtsc_x2y(rtsc, x);
615 if (y1 <= y) {
616 /* rtsc is below isc, no change to rtsc */
617 return;
618 }
619
620 y2 = rtsc_x2y(rtsc, x + isc->dx);
621 if (y2 >= y + isc->dy) {
622 /* rtsc is above isc, replace rtsc by isc */
623 rtsc->x = x;
624 rtsc->y = y;
625 rtsc->dx = isc->dx;
626 rtsc->dy = isc->dy;
627 return;
628 }
629
630 /*
631 * the two curves intersect
632 * compute the offsets (dx, dy) using the reverse
633 * function of seg_x2y()
634 * seg_x2y(dx, sm1) == seg_x2y(dx, sm2) + (y1 - y)
635 */
636 dx = (y1 - y) << SM_SHIFT;
637 dsm = isc->sm1 - isc->sm2;
638 do_div(dx, dsm);
639 /*
640 * check if (x, y1) belongs to the 1st segment of rtsc.
641 * if so, add the offset.
642 */
643 if (rtsc->x + rtsc->dx > x)
644 dx += rtsc->x + rtsc->dx - x;
645 dy = seg_x2y(dx, isc->sm1);
646
647 rtsc->x = x;
648 rtsc->y = y;
649 rtsc->dx = dx;
650 rtsc->dy = dy;
651 return;
652 }
653
654 static void
655 init_ed(struct hfsc_class *cl, unsigned int next_len)
656 {
657 u64 cur_time;
658
659 PSCHED_GET_TIME(cur_time);
660
661 /* update the deadline curve */
662 rtsc_min(&cl->cl_deadline, &cl->cl_rsc, cur_time, cl->cl_cumul);
663
664 /*
665 * update the eligible curve.
666 * for concave, it is equal to the deadline curve.
667 * for convex, it is a linear curve with slope m2.
668 */
669 cl->cl_eligible = cl->cl_deadline;
670 if (cl->cl_rsc.sm1 <= cl->cl_rsc.sm2) {
671 cl->cl_eligible.dx = 0;
672 cl->cl_eligible.dy = 0;
673 }
674
675 /* compute e and d */
676 cl->cl_e = rtsc_y2x(&cl->cl_eligible, cl->cl_cumul);
677 cl->cl_d = rtsc_y2x(&cl->cl_deadline, cl->cl_cumul + next_len);
678
679 eltree_insert(cl);
680 }
681
682 static void
683 update_ed(struct hfsc_class *cl, unsigned int next_len)
684 {
685 cl->cl_e = rtsc_y2x(&cl->cl_eligible, cl->cl_cumul);
686 cl->cl_d = rtsc_y2x(&cl->cl_deadline, cl->cl_cumul + next_len);
687
688 eltree_update(cl);
689 }
690
691 static inline void
692 update_d(struct hfsc_class *cl, unsigned int next_len)
693 {
694 cl->cl_d = rtsc_y2x(&cl->cl_deadline, cl->cl_cumul + next_len);
695 }
696
697 static inline void
698 update_cfmin(struct hfsc_class *cl)
699 {
700 struct rb_node *n = rb_first(&cl->cf_tree);
701 struct hfsc_class *p;
702
703 if (n == NULL) {
704 cl->cl_cfmin = 0;
705 return;
706 }
707 p = rb_entry(n, struct hfsc_class, cf_node);
708 cl->cl_cfmin = p->cl_f;
709 }
710
711 static void
712 init_vf(struct hfsc_class *cl, unsigned int len)
713 {
714 struct hfsc_class *max_cl;
715 struct rb_node *n;
716 u64 vt, f, cur_time;
717 int go_active;
718
719 cur_time = 0;
720 go_active = 1;
721 for (; cl->cl_parent != NULL; cl = cl->cl_parent) {
722 if (go_active && cl->cl_nactive++ == 0)
723 go_active = 1;
724 else
725 go_active = 0;
726
727 if (go_active) {
728 n = rb_last(&cl->cl_parent->vt_tree);
729 if (n != NULL) {
730 max_cl = rb_entry(n, struct hfsc_class,vt_node);
731 /*
732 * set vt to the average of the min and max
733 * classes. if the parent's period didn't
734 * change, don't decrease vt of the class.
735 */
736 vt = max_cl->cl_vt;
737 if (cl->cl_parent->cl_cvtmin != 0)
738 vt = (cl->cl_parent->cl_cvtmin + vt)/2;
739
740 if (cl->cl_parent->cl_vtperiod !=
741 cl->cl_parentperiod || vt > cl->cl_vt)
742 cl->cl_vt = vt;
743 } else {
744 /*
745 * first child for a new parent backlog period.
746 * add parent's cvtmax to cvtoff to make a new
747 * vt (vtoff + vt) larger than the vt in the
748 * last period for all children.
749 */
750 vt = cl->cl_parent->cl_cvtmax;
751 cl->cl_parent->cl_cvtoff += vt;
752 cl->cl_parent->cl_cvtmax = 0;
753 cl->cl_parent->cl_cvtmin = 0;
754 cl->cl_vt = 0;
755 }
756
757 cl->cl_vtoff = cl->cl_parent->cl_cvtoff -
758 cl->cl_pcvtoff;
759
760 /* update the virtual curve */
761 vt = cl->cl_vt + cl->cl_vtoff;
762 rtsc_min(&cl->cl_virtual, &cl->cl_fsc, vt,
763 cl->cl_total);
764 if (cl->cl_virtual.x == vt) {
765 cl->cl_virtual.x -= cl->cl_vtoff;
766 cl->cl_vtoff = 0;
767 }
768 cl->cl_vtadj = 0;
769
770 cl->cl_vtperiod++; /* increment vt period */
771 cl->cl_parentperiod = cl->cl_parent->cl_vtperiod;
772 if (cl->cl_parent->cl_nactive == 0)
773 cl->cl_parentperiod++;
774 cl->cl_f = 0;
775
776 vttree_insert(cl);
777 cftree_insert(cl);
778
779 if (cl->cl_flags & HFSC_USC) {
780 /* class has upper limit curve */
781 if (cur_time == 0)
782 PSCHED_GET_TIME(cur_time);
783
784 /* update the ulimit curve */
785 rtsc_min(&cl->cl_ulimit, &cl->cl_usc, cur_time,
786 cl->cl_total);
787 /* compute myf */
788 cl->cl_myf = rtsc_y2x(&cl->cl_ulimit,
789 cl->cl_total);
790 cl->cl_myfadj = 0;
791 }
792 }
793
794 f = max(cl->cl_myf, cl->cl_cfmin);
795 if (f != cl->cl_f) {
796 cl->cl_f = f;
797 cftree_update(cl);
798 update_cfmin(cl->cl_parent);
799 }
800 }
801 }
802
803 static void
804 update_vf(struct hfsc_class *cl, unsigned int len, u64 cur_time)
805 {
806 u64 f; /* , myf_bound, delta; */
807 int go_passive = 0;
808
809 if (cl->qdisc->q.qlen == 0 && cl->cl_flags & HFSC_FSC)
810 go_passive = 1;
811
812 for (; cl->cl_parent != NULL; cl = cl->cl_parent) {
813 cl->cl_total += len;
814
815 if (!(cl->cl_flags & HFSC_FSC) || cl->cl_nactive == 0)
816 continue;
817
818 if (go_passive && --cl->cl_nactive == 0)
819 go_passive = 1;
820 else
821 go_passive = 0;
822
823 if (go_passive) {
824 /* no more active child, going passive */
825
826 /* update cvtmax of the parent class */
827 if (cl->cl_vt > cl->cl_parent->cl_cvtmax)
828 cl->cl_parent->cl_cvtmax = cl->cl_vt;
829
830 /* remove this class from the vt tree */
831 vttree_remove(cl);
832
833 cftree_remove(cl);
834 update_cfmin(cl->cl_parent);
835
836 continue;
837 }
838
839 /*
840 * update vt and f
841 */
842 cl->cl_vt = rtsc_y2x(&cl->cl_virtual, cl->cl_total)
843 - cl->cl_vtoff + cl->cl_vtadj;
844
845 /*
846 * if vt of the class is smaller than cvtmin,
847 * the class was skipped in the past due to non-fit.
848 * if so, we need to adjust vtadj.
849 */
850 if (cl->cl_vt < cl->cl_parent->cl_cvtmin) {
851 cl->cl_vtadj += cl->cl_parent->cl_cvtmin - cl->cl_vt;
852 cl->cl_vt = cl->cl_parent->cl_cvtmin;
853 }
854
855 /* update the vt tree */
856 vttree_update(cl);
857
858 if (cl->cl_flags & HFSC_USC) {
859 cl->cl_myf = cl->cl_myfadj + rtsc_y2x(&cl->cl_ulimit,
860 cl->cl_total);
861 #if 0
862 /*
863 * This code causes classes to stay way under their
864 * limit when multiple classes are used at gigabit
865 * speed. needs investigation. -kaber
866 */
867 /*
868 * if myf lags behind by more than one clock tick
869 * from the current time, adjust myfadj to prevent
870 * a rate-limited class from going greedy.
871 * in a steady state under rate-limiting, myf
872 * fluctuates within one clock tick.
873 */
874 myf_bound = cur_time - PSCHED_JIFFIE2US(1);
875 if (cl->cl_myf < myf_bound) {
876 delta = cur_time - cl->cl_myf;
877 cl->cl_myfadj += delta;
878 cl->cl_myf += delta;
879 }
880 #endif
881 }
882
883 f = max(cl->cl_myf, cl->cl_cfmin);
884 if (f != cl->cl_f) {
885 cl->cl_f = f;
886 cftree_update(cl);
887 update_cfmin(cl->cl_parent);
888 }
889 }
890 }
891
892 static void
893 set_active(struct hfsc_class *cl, unsigned int len)
894 {
895 if (cl->cl_flags & HFSC_RSC)
896 init_ed(cl, len);
897 if (cl->cl_flags & HFSC_FSC)
898 init_vf(cl, len);
899
900 list_add_tail(&cl->dlist, &cl->sched->droplist);
901 }
902
903 static void
904 set_passive(struct hfsc_class *cl)
905 {
906 if (cl->cl_flags & HFSC_RSC)
907 eltree_remove(cl);
908
909 list_del(&cl->dlist);
910
911 /*
912 * vttree is now handled in update_vf() so that update_vf(cl, 0, 0)
913 * needs to be called explicitly to remove a class from vttree.
914 */
915 }
916
917 /*
918 * hack to get length of first packet in queue.
919 */
920 static unsigned int
921 qdisc_peek_len(struct Qdisc *sch)
922 {
923 struct sk_buff *skb;
924 unsigned int len;
925
926 skb = sch->dequeue(sch);
927 if (skb == NULL) {
928 if (net_ratelimit())
929 printk("qdisc_peek_len: non work-conserving qdisc ?\n");
930 return 0;
931 }
932 len = skb->len;
933 if (unlikely(sch->ops->requeue(skb, sch) != NET_XMIT_SUCCESS)) {
934 if (net_ratelimit())
935 printk("qdisc_peek_len: failed to requeue\n");
936 qdisc_tree_decrease_qlen(sch, 1);
937 return 0;
938 }
939 return len;
940 }
941
942 static void
943 hfsc_purge_queue(struct Qdisc *sch, struct hfsc_class *cl)
944 {
945 unsigned int len = cl->qdisc->q.qlen;
946
947 qdisc_reset(cl->qdisc);
948 qdisc_tree_decrease_qlen(cl->qdisc, len);
949 }
950
951 static void
952 hfsc_adjust_levels(struct hfsc_class *cl)
953 {
954 struct hfsc_class *p;
955 unsigned int level;
956
957 do {
958 level = 0;
959 list_for_each_entry(p, &cl->children, siblings) {
960 if (p->level >= level)
961 level = p->level + 1;
962 }
963 cl->level = level;
964 } while ((cl = cl->cl_parent) != NULL);
965 }
966
967 static inline unsigned int
968 hfsc_hash(u32 h)
969 {
970 h ^= h >> 8;
971 h ^= h >> 4;
972
973 return h & (HFSC_HSIZE - 1);
974 }
975
976 static inline struct hfsc_class *
977 hfsc_find_class(u32 classid, struct Qdisc *sch)
978 {
979 struct hfsc_sched *q = qdisc_priv(sch);
980 struct hfsc_class *cl;
981
982 list_for_each_entry(cl, &q->clhash[hfsc_hash(classid)], hlist) {
983 if (cl->classid == classid)
984 return cl;
985 }
986 return NULL;
987 }
988
989 static void
990 hfsc_change_rsc(struct hfsc_class *cl, struct tc_service_curve *rsc,
991 u64 cur_time)
992 {
993 sc2isc(rsc, &cl->cl_rsc);
994 rtsc_init(&cl->cl_deadline, &cl->cl_rsc, cur_time, cl->cl_cumul);
995 cl->cl_eligible = cl->cl_deadline;
996 if (cl->cl_rsc.sm1 <= cl->cl_rsc.sm2) {
997 cl->cl_eligible.dx = 0;
998 cl->cl_eligible.dy = 0;
999 }
1000 cl->cl_flags |= HFSC_RSC;
1001 }
1002
1003 static void
1004 hfsc_change_fsc(struct hfsc_class *cl, struct tc_service_curve *fsc)
1005 {
1006 sc2isc(fsc, &cl->cl_fsc);
1007 rtsc_init(&cl->cl_virtual, &cl->cl_fsc, cl->cl_vt, cl->cl_total);
1008 cl->cl_flags |= HFSC_FSC;
1009 }
1010
1011 static void
1012 hfsc_change_usc(struct hfsc_class *cl, struct tc_service_curve *usc,
1013 u64 cur_time)
1014 {
1015 sc2isc(usc, &cl->cl_usc);
1016 rtsc_init(&cl->cl_ulimit, &cl->cl_usc, cur_time, cl->cl_total);
1017 cl->cl_flags |= HFSC_USC;
1018 }
1019
1020 static int
1021 hfsc_change_class(struct Qdisc *sch, u32 classid, u32 parentid,
1022 struct rtattr **tca, unsigned long *arg)
1023 {
1024 struct hfsc_sched *q = qdisc_priv(sch);
1025 struct hfsc_class *cl = (struct hfsc_class *)*arg;
1026 struct hfsc_class *parent = NULL;
1027 struct rtattr *opt = tca[TCA_OPTIONS-1];
1028 struct rtattr *tb[TCA_HFSC_MAX];
1029 struct tc_service_curve *rsc = NULL, *fsc = NULL, *usc = NULL;
1030 u64 cur_time;
1031
1032 if (opt == NULL || rtattr_parse_nested(tb, TCA_HFSC_MAX, opt))
1033 return -EINVAL;
1034
1035 if (tb[TCA_HFSC_RSC-1]) {
1036 if (RTA_PAYLOAD(tb[TCA_HFSC_RSC-1]) < sizeof(*rsc))
1037 return -EINVAL;
1038 rsc = RTA_DATA(tb[TCA_HFSC_RSC-1]);
1039 if (rsc->m1 == 0 && rsc->m2 == 0)
1040 rsc = NULL;
1041 }
1042
1043 if (tb[TCA_HFSC_FSC-1]) {
1044 if (RTA_PAYLOAD(tb[TCA_HFSC_FSC-1]) < sizeof(*fsc))
1045 return -EINVAL;
1046 fsc = RTA_DATA(tb[TCA_HFSC_FSC-1]);
1047 if (fsc->m1 == 0 && fsc->m2 == 0)
1048 fsc = NULL;
1049 }
1050
1051 if (tb[TCA_HFSC_USC-1]) {
1052 if (RTA_PAYLOAD(tb[TCA_HFSC_USC-1]) < sizeof(*usc))
1053 return -EINVAL;
1054 usc = RTA_DATA(tb[TCA_HFSC_USC-1]);
1055 if (usc->m1 == 0 && usc->m2 == 0)
1056 usc = NULL;
1057 }
1058
1059 if (cl != NULL) {
1060 if (parentid) {
1061 if (cl->cl_parent && cl->cl_parent->classid != parentid)
1062 return -EINVAL;
1063 if (cl->cl_parent == NULL && parentid != TC_H_ROOT)
1064 return -EINVAL;
1065 }
1066 PSCHED_GET_TIME(cur_time);
1067
1068 sch_tree_lock(sch);
1069 if (rsc != NULL)
1070 hfsc_change_rsc(cl, rsc, cur_time);
1071 if (fsc != NULL)
1072 hfsc_change_fsc(cl, fsc);
1073 if (usc != NULL)
1074 hfsc_change_usc(cl, usc, cur_time);
1075
1076 if (cl->qdisc->q.qlen != 0) {
1077 if (cl->cl_flags & HFSC_RSC)
1078 update_ed(cl, qdisc_peek_len(cl->qdisc));
1079 if (cl->cl_flags & HFSC_FSC)
1080 update_vf(cl, 0, cur_time);
1081 }
1082 sch_tree_unlock(sch);
1083
1084 #ifdef CONFIG_NET_ESTIMATOR
1085 if (tca[TCA_RATE-1])
1086 gen_replace_estimator(&cl->bstats, &cl->rate_est,
1087 cl->stats_lock, tca[TCA_RATE-1]);
1088 #endif
1089 return 0;
1090 }
1091
1092 if (parentid == TC_H_ROOT)
1093 return -EEXIST;
1094
1095 parent = &q->root;
1096 if (parentid) {
1097 parent = hfsc_find_class(parentid, sch);
1098 if (parent == NULL)
1099 return -ENOENT;
1100 }
1101
1102 if (classid == 0 || TC_H_MAJ(classid ^ sch->handle) != 0)
1103 return -EINVAL;
1104 if (hfsc_find_class(classid, sch))
1105 return -EEXIST;
1106
1107 if (rsc == NULL && fsc == NULL)
1108 return -EINVAL;
1109
1110 cl = kzalloc(sizeof(struct hfsc_class), GFP_KERNEL);
1111 if (cl == NULL)
1112 return -ENOBUFS;
1113
1114 if (rsc != NULL)
1115 hfsc_change_rsc(cl, rsc, 0);
1116 if (fsc != NULL)
1117 hfsc_change_fsc(cl, fsc);
1118 if (usc != NULL)
1119 hfsc_change_usc(cl, usc, 0);
1120
1121 cl->refcnt = 1;
1122 cl->classid = classid;
1123 cl->sched = q;
1124 cl->cl_parent = parent;
1125 cl->qdisc = qdisc_create_dflt(sch->dev, &pfifo_qdisc_ops, classid);
1126 if (cl->qdisc == NULL)
1127 cl->qdisc = &noop_qdisc;
1128 cl->stats_lock = &sch->dev->queue_lock;
1129 INIT_LIST_HEAD(&cl->children);
1130 cl->vt_tree = RB_ROOT;
1131 cl->cf_tree = RB_ROOT;
1132
1133 sch_tree_lock(sch);
1134 list_add_tail(&cl->hlist, &q->clhash[hfsc_hash(classid)]);
1135 list_add_tail(&cl->siblings, &parent->children);
1136 if (parent->level == 0)
1137 hfsc_purge_queue(sch, parent);
1138 hfsc_adjust_levels(parent);
1139 cl->cl_pcvtoff = parent->cl_cvtoff;
1140 sch_tree_unlock(sch);
1141
1142 #ifdef CONFIG_NET_ESTIMATOR
1143 if (tca[TCA_RATE-1])
1144 gen_new_estimator(&cl->bstats, &cl->rate_est,
1145 cl->stats_lock, tca[TCA_RATE-1]);
1146 #endif
1147 *arg = (unsigned long)cl;
1148 return 0;
1149 }
1150
1151 static void
1152 hfsc_destroy_filters(struct tcf_proto **fl)
1153 {
1154 struct tcf_proto *tp;
1155
1156 while ((tp = *fl) != NULL) {
1157 *fl = tp->next;
1158 tcf_destroy(tp);
1159 }
1160 }
1161
1162 static void
1163 hfsc_destroy_class(struct Qdisc *sch, struct hfsc_class *cl)
1164 {
1165 struct hfsc_sched *q = qdisc_priv(sch);
1166
1167 hfsc_destroy_filters(&cl->filter_list);
1168 qdisc_destroy(cl->qdisc);
1169 #ifdef CONFIG_NET_ESTIMATOR
1170 gen_kill_estimator(&cl->bstats, &cl->rate_est);
1171 #endif
1172 if (cl != &q->root)
1173 kfree(cl);
1174 }
1175
1176 static int
1177 hfsc_delete_class(struct Qdisc *sch, unsigned long arg)
1178 {
1179 struct hfsc_sched *q = qdisc_priv(sch);
1180 struct hfsc_class *cl = (struct hfsc_class *)arg;
1181
1182 if (cl->level > 0 || cl->filter_cnt > 0 || cl == &q->root)
1183 return -EBUSY;
1184
1185 sch_tree_lock(sch);
1186
1187 list_del(&cl->hlist);
1188 list_del(&cl->siblings);
1189 hfsc_adjust_levels(cl->cl_parent);
1190 hfsc_purge_queue(sch, cl);
1191 if (--cl->refcnt == 0)
1192 hfsc_destroy_class(sch, cl);
1193
1194 sch_tree_unlock(sch);
1195 return 0;
1196 }
1197
1198 static struct hfsc_class *
1199 hfsc_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr)
1200 {
1201 struct hfsc_sched *q = qdisc_priv(sch);
1202 struct hfsc_class *cl;
1203 struct tcf_result res;
1204 struct tcf_proto *tcf;
1205 int result;
1206
1207 if (TC_H_MAJ(skb->priority ^ sch->handle) == 0 &&
1208 (cl = hfsc_find_class(skb->priority, sch)) != NULL)
1209 if (cl->level == 0)
1210 return cl;
1211
1212 *qerr = NET_XMIT_BYPASS;
1213 tcf = q->root.filter_list;
1214 while (tcf && (result = tc_classify(skb, tcf, &res)) >= 0) {
1215 #ifdef CONFIG_NET_CLS_ACT
1216 switch (result) {
1217 case TC_ACT_QUEUED:
1218 case TC_ACT_STOLEN:
1219 *qerr = NET_XMIT_SUCCESS;
1220 case TC_ACT_SHOT:
1221 return NULL;
1222 }
1223 #elif defined(CONFIG_NET_CLS_POLICE)
1224 if (result == TC_POLICE_SHOT)
1225 return NULL;
1226 #endif
1227 if ((cl = (struct hfsc_class *)res.class) == NULL) {
1228 if ((cl = hfsc_find_class(res.classid, sch)) == NULL)
1229 break; /* filter selected invalid classid */
1230 }
1231
1232 if (cl->level == 0)
1233 return cl; /* hit leaf class */
1234
1235 /* apply inner filter chain */
1236 tcf = cl->filter_list;
1237 }
1238
1239 /* classification failed, try default class */
1240 cl = hfsc_find_class(TC_H_MAKE(TC_H_MAJ(sch->handle), q->defcls), sch);
1241 if (cl == NULL || cl->level > 0)
1242 return NULL;
1243
1244 return cl;
1245 }
1246
1247 static int
1248 hfsc_graft_class(struct Qdisc *sch, unsigned long arg, struct Qdisc *new,
1249 struct Qdisc **old)
1250 {
1251 struct hfsc_class *cl = (struct hfsc_class *)arg;
1252
1253 if (cl == NULL)
1254 return -ENOENT;
1255 if (cl->level > 0)
1256 return -EINVAL;
1257 if (new == NULL) {
1258 new = qdisc_create_dflt(sch->dev, &pfifo_qdisc_ops,
1259 cl->classid);
1260 if (new == NULL)
1261 new = &noop_qdisc;
1262 }
1263
1264 sch_tree_lock(sch);
1265 hfsc_purge_queue(sch, cl);
1266 *old = xchg(&cl->qdisc, new);
1267 sch_tree_unlock(sch);
1268 return 0;
1269 }
1270
1271 static struct Qdisc *
1272 hfsc_class_leaf(struct Qdisc *sch, unsigned long arg)
1273 {
1274 struct hfsc_class *cl = (struct hfsc_class *)arg;
1275
1276 if (cl != NULL && cl->level == 0)
1277 return cl->qdisc;
1278
1279 return NULL;
1280 }
1281
1282 static void
1283 hfsc_qlen_notify(struct Qdisc *sch, unsigned long arg)
1284 {
1285 struct hfsc_class *cl = (struct hfsc_class *)arg;
1286
1287 if (cl->qdisc->q.qlen == 0) {
1288 update_vf(cl, 0, 0);
1289 set_passive(cl);
1290 }
1291 }
1292
1293 static unsigned long
1294 hfsc_get_class(struct Qdisc *sch, u32 classid)
1295 {
1296 struct hfsc_class *cl = hfsc_find_class(classid, sch);
1297
1298 if (cl != NULL)
1299 cl->refcnt++;
1300
1301 return (unsigned long)cl;
1302 }
1303
1304 static void
1305 hfsc_put_class(struct Qdisc *sch, unsigned long arg)
1306 {
1307 struct hfsc_class *cl = (struct hfsc_class *)arg;
1308
1309 if (--cl->refcnt == 0)
1310 hfsc_destroy_class(sch, cl);
1311 }
1312
1313 static unsigned long
1314 hfsc_bind_tcf(struct Qdisc *sch, unsigned long parent, u32 classid)
1315 {
1316 struct hfsc_class *p = (struct hfsc_class *)parent;
1317 struct hfsc_class *cl = hfsc_find_class(classid, sch);
1318
1319 if (cl != NULL) {
1320 if (p != NULL && p->level <= cl->level)
1321 return 0;
1322 cl->filter_cnt++;
1323 }
1324
1325 return (unsigned long)cl;
1326 }
1327
1328 static void
1329 hfsc_unbind_tcf(struct Qdisc *sch, unsigned long arg)
1330 {
1331 struct hfsc_class *cl = (struct hfsc_class *)arg;
1332
1333 cl->filter_cnt--;
1334 }
1335
1336 static struct tcf_proto **
1337 hfsc_tcf_chain(struct Qdisc *sch, unsigned long arg)
1338 {
1339 struct hfsc_sched *q = qdisc_priv(sch);
1340 struct hfsc_class *cl = (struct hfsc_class *)arg;
1341
1342 if (cl == NULL)
1343 cl = &q->root;
1344
1345 return &cl->filter_list;
1346 }
1347
1348 static int
1349 hfsc_dump_sc(struct sk_buff *skb, int attr, struct internal_sc *sc)
1350 {
1351 struct tc_service_curve tsc;
1352
1353 tsc.m1 = sm2m(sc->sm1);
1354 tsc.d = dx2d(sc->dx);
1355 tsc.m2 = sm2m(sc->sm2);
1356 RTA_PUT(skb, attr, sizeof(tsc), &tsc);
1357
1358 return skb->len;
1359
1360 rtattr_failure:
1361 return -1;
1362 }
1363
1364 static inline int
1365 hfsc_dump_curves(struct sk_buff *skb, struct hfsc_class *cl)
1366 {
1367 if ((cl->cl_flags & HFSC_RSC) &&
1368 (hfsc_dump_sc(skb, TCA_HFSC_RSC, &cl->cl_rsc) < 0))
1369 goto rtattr_failure;
1370
1371 if ((cl->cl_flags & HFSC_FSC) &&
1372 (hfsc_dump_sc(skb, TCA_HFSC_FSC, &cl->cl_fsc) < 0))
1373 goto rtattr_failure;
1374
1375 if ((cl->cl_flags & HFSC_USC) &&
1376 (hfsc_dump_sc(skb, TCA_HFSC_USC, &cl->cl_usc) < 0))
1377 goto rtattr_failure;
1378
1379 return skb->len;
1380
1381 rtattr_failure:
1382 return -1;
1383 }
1384
1385 static int
1386 hfsc_dump_class(struct Qdisc *sch, unsigned long arg, struct sk_buff *skb,
1387 struct tcmsg *tcm)
1388 {
1389 struct hfsc_class *cl = (struct hfsc_class *)arg;
1390 unsigned char *b = skb->tail;
1391 struct rtattr *rta = (struct rtattr *)b;
1392
1393 tcm->tcm_parent = cl->cl_parent ? cl->cl_parent->classid : TC_H_ROOT;
1394 tcm->tcm_handle = cl->classid;
1395 if (cl->level == 0)
1396 tcm->tcm_info = cl->qdisc->handle;
1397
1398 RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
1399 if (hfsc_dump_curves(skb, cl) < 0)
1400 goto rtattr_failure;
1401 rta->rta_len = skb->tail - b;
1402 return skb->len;
1403
1404 rtattr_failure:
1405 skb_trim(skb, b - skb->data);
1406 return -1;
1407 }
1408
1409 static int
1410 hfsc_dump_class_stats(struct Qdisc *sch, unsigned long arg,
1411 struct gnet_dump *d)
1412 {
1413 struct hfsc_class *cl = (struct hfsc_class *)arg;
1414 struct tc_hfsc_stats xstats;
1415
1416 cl->qstats.qlen = cl->qdisc->q.qlen;
1417 xstats.level = cl->level;
1418 xstats.period = cl->cl_vtperiod;
1419 xstats.work = cl->cl_total;
1420 xstats.rtwork = cl->cl_cumul;
1421
1422 if (gnet_stats_copy_basic(d, &cl->bstats) < 0 ||
1423 #ifdef CONFIG_NET_ESTIMATOR
1424 gnet_stats_copy_rate_est(d, &cl->rate_est) < 0 ||
1425 #endif
1426 gnet_stats_copy_queue(d, &cl->qstats) < 0)
1427 return -1;
1428
1429 return gnet_stats_copy_app(d, &xstats, sizeof(xstats));
1430 }
1431
1432
1433
1434 static void
1435 hfsc_walk(struct Qdisc *sch, struct qdisc_walker *arg)
1436 {
1437 struct hfsc_sched *q = qdisc_priv(sch);
1438 struct hfsc_class *cl;
1439 unsigned int i;
1440
1441 if (arg->stop)
1442 return;
1443
1444 for (i = 0; i < HFSC_HSIZE; i++) {
1445 list_for_each_entry(cl, &q->clhash[i], hlist) {
1446 if (arg->count < arg->skip) {
1447 arg->count++;
1448 continue;
1449 }
1450 if (arg->fn(sch, (unsigned long)cl, arg) < 0) {
1451 arg->stop = 1;
1452 return;
1453 }
1454 arg->count++;
1455 }
1456 }
1457 }
1458
1459 static void
1460 hfsc_watchdog(unsigned long arg)
1461 {
1462 struct Qdisc *sch = (struct Qdisc *)arg;
1463
1464 sch->flags &= ~TCQ_F_THROTTLED;
1465 netif_schedule(sch->dev);
1466 }
1467
1468 static void
1469 hfsc_schedule_watchdog(struct Qdisc *sch, u64 cur_time)
1470 {
1471 struct hfsc_sched *q = qdisc_priv(sch);
1472 struct hfsc_class *cl;
1473 u64 next_time = 0;
1474 long delay;
1475
1476 if ((cl = eltree_get_minel(q)) != NULL)
1477 next_time = cl->cl_e;
1478 if (q->root.cl_cfmin != 0) {
1479 if (next_time == 0 || next_time > q->root.cl_cfmin)
1480 next_time = q->root.cl_cfmin;
1481 }
1482 WARN_ON(next_time == 0);
1483 delay = next_time - cur_time;
1484 delay = PSCHED_US2JIFFIE(delay);
1485
1486 sch->flags |= TCQ_F_THROTTLED;
1487 mod_timer(&q->wd_timer, jiffies + delay);
1488 }
1489
1490 static int
1491 hfsc_init_qdisc(struct Qdisc *sch, struct rtattr *opt)
1492 {
1493 struct hfsc_sched *q = qdisc_priv(sch);
1494 struct tc_hfsc_qopt *qopt;
1495 unsigned int i;
1496
1497 if (opt == NULL || RTA_PAYLOAD(opt) < sizeof(*qopt))
1498 return -EINVAL;
1499 qopt = RTA_DATA(opt);
1500
1501 sch->stats_lock = &sch->dev->queue_lock;
1502
1503 q->defcls = qopt->defcls;
1504 for (i = 0; i < HFSC_HSIZE; i++)
1505 INIT_LIST_HEAD(&q->clhash[i]);
1506 q->eligible = RB_ROOT;
1507 INIT_LIST_HEAD(&q->droplist);
1508 skb_queue_head_init(&q->requeue);
1509
1510 q->root.refcnt = 1;
1511 q->root.classid = sch->handle;
1512 q->root.sched = q;
1513 q->root.qdisc = qdisc_create_dflt(sch->dev, &pfifo_qdisc_ops,
1514 sch->handle);
1515 if (q->root.qdisc == NULL)
1516 q->root.qdisc = &noop_qdisc;
1517 q->root.stats_lock = &sch->dev->queue_lock;
1518 INIT_LIST_HEAD(&q->root.children);
1519 q->root.vt_tree = RB_ROOT;
1520 q->root.cf_tree = RB_ROOT;
1521
1522 list_add(&q->root.hlist, &q->clhash[hfsc_hash(q->root.classid)]);
1523
1524 init_timer(&q->wd_timer);
1525 q->wd_timer.function = hfsc_watchdog;
1526 q->wd_timer.data = (unsigned long)sch;
1527
1528 return 0;
1529 }
1530
1531 static int
1532 hfsc_change_qdisc(struct Qdisc *sch, struct rtattr *opt)
1533 {
1534 struct hfsc_sched *q = qdisc_priv(sch);
1535 struct tc_hfsc_qopt *qopt;
1536
1537 if (opt == NULL || RTA_PAYLOAD(opt) < sizeof(*qopt))
1538 return -EINVAL;
1539 qopt = RTA_DATA(opt);
1540
1541 sch_tree_lock(sch);
1542 q->defcls = qopt->defcls;
1543 sch_tree_unlock(sch);
1544
1545 return 0;
1546 }
1547
1548 static void
1549 hfsc_reset_class(struct hfsc_class *cl)
1550 {
1551 cl->cl_total = 0;
1552 cl->cl_cumul = 0;
1553 cl->cl_d = 0;
1554 cl->cl_e = 0;
1555 cl->cl_vt = 0;
1556 cl->cl_vtadj = 0;
1557 cl->cl_vtoff = 0;
1558 cl->cl_cvtmin = 0;
1559 cl->cl_cvtmax = 0;
1560 cl->cl_cvtoff = 0;
1561 cl->cl_pcvtoff = 0;
1562 cl->cl_vtperiod = 0;
1563 cl->cl_parentperiod = 0;
1564 cl->cl_f = 0;
1565 cl->cl_myf = 0;
1566 cl->cl_myfadj = 0;
1567 cl->cl_cfmin = 0;
1568 cl->cl_nactive = 0;
1569
1570 cl->vt_tree = RB_ROOT;
1571 cl->cf_tree = RB_ROOT;
1572 qdisc_reset(cl->qdisc);
1573
1574 if (cl->cl_flags & HFSC_RSC)
1575 rtsc_init(&cl->cl_deadline, &cl->cl_rsc, 0, 0);
1576 if (cl->cl_flags & HFSC_FSC)
1577 rtsc_init(&cl->cl_virtual, &cl->cl_fsc, 0, 0);
1578 if (cl->cl_flags & HFSC_USC)
1579 rtsc_init(&cl->cl_ulimit, &cl->cl_usc, 0, 0);
1580 }
1581
1582 static void
1583 hfsc_reset_qdisc(struct Qdisc *sch)
1584 {
1585 struct hfsc_sched *q = qdisc_priv(sch);
1586 struct hfsc_class *cl;
1587 unsigned int i;
1588
1589 for (i = 0; i < HFSC_HSIZE; i++) {
1590 list_for_each_entry(cl, &q->clhash[i], hlist)
1591 hfsc_reset_class(cl);
1592 }
1593 __skb_queue_purge(&q->requeue);
1594 q->eligible = RB_ROOT;
1595 INIT_LIST_HEAD(&q->droplist);
1596 del_timer(&q->wd_timer);
1597 sch->flags &= ~TCQ_F_THROTTLED;
1598 sch->q.qlen = 0;
1599 }
1600
1601 static void
1602 hfsc_destroy_qdisc(struct Qdisc *sch)
1603 {
1604 struct hfsc_sched *q = qdisc_priv(sch);
1605 struct hfsc_class *cl, *next;
1606 unsigned int i;
1607
1608 for (i = 0; i < HFSC_HSIZE; i++) {
1609 list_for_each_entry_safe(cl, next, &q->clhash[i], hlist)
1610 hfsc_destroy_class(sch, cl);
1611 }
1612 __skb_queue_purge(&q->requeue);
1613 del_timer(&q->wd_timer);
1614 }
1615
1616 static int
1617 hfsc_dump_qdisc(struct Qdisc *sch, struct sk_buff *skb)
1618 {
1619 struct hfsc_sched *q = qdisc_priv(sch);
1620 unsigned char *b = skb->tail;
1621 struct tc_hfsc_qopt qopt;
1622
1623 qopt.defcls = q->defcls;
1624 RTA_PUT(skb, TCA_OPTIONS, sizeof(qopt), &qopt);
1625 return skb->len;
1626
1627 rtattr_failure:
1628 skb_trim(skb, b - skb->data);
1629 return -1;
1630 }
1631
1632 static int
1633 hfsc_enqueue(struct sk_buff *skb, struct Qdisc *sch)
1634 {
1635 struct hfsc_class *cl;
1636 unsigned int len;
1637 int err;
1638
1639 cl = hfsc_classify(skb, sch, &err);
1640 if (cl == NULL) {
1641 if (err == NET_XMIT_BYPASS)
1642 sch->qstats.drops++;
1643 kfree_skb(skb);
1644 return err;
1645 }
1646
1647 len = skb->len;
1648 err = cl->qdisc->enqueue(skb, cl->qdisc);
1649 if (unlikely(err != NET_XMIT_SUCCESS)) {
1650 cl->qstats.drops++;
1651 sch->qstats.drops++;
1652 return err;
1653 }
1654
1655 if (cl->qdisc->q.qlen == 1)
1656 set_active(cl, len);
1657
1658 cl->bstats.packets++;
1659 cl->bstats.bytes += len;
1660 sch->bstats.packets++;
1661 sch->bstats.bytes += len;
1662 sch->q.qlen++;
1663
1664 return NET_XMIT_SUCCESS;
1665 }
1666
1667 static struct sk_buff *
1668 hfsc_dequeue(struct Qdisc *sch)
1669 {
1670 struct hfsc_sched *q = qdisc_priv(sch);
1671 struct hfsc_class *cl;
1672 struct sk_buff *skb;
1673 u64 cur_time;
1674 unsigned int next_len;
1675 int realtime = 0;
1676
1677 if (sch->q.qlen == 0)
1678 return NULL;
1679 if ((skb = __skb_dequeue(&q->requeue)))
1680 goto out;
1681
1682 PSCHED_GET_TIME(cur_time);
1683
1684 /*
1685 * if there are eligible classes, use real-time criteria.
1686 * find the class with the minimum deadline among
1687 * the eligible classes.
1688 */
1689 if ((cl = eltree_get_mindl(q, cur_time)) != NULL) {
1690 realtime = 1;
1691 } else {
1692 /*
1693 * use link-sharing criteria
1694 * get the class with the minimum vt in the hierarchy
1695 */
1696 cl = vttree_get_minvt(&q->root, cur_time);
1697 if (cl == NULL) {
1698 sch->qstats.overlimits++;
1699 hfsc_schedule_watchdog(sch, cur_time);
1700 return NULL;
1701 }
1702 }
1703
1704 skb = cl->qdisc->dequeue(cl->qdisc);
1705 if (skb == NULL) {
1706 if (net_ratelimit())
1707 printk("HFSC: Non-work-conserving qdisc ?\n");
1708 return NULL;
1709 }
1710
1711 update_vf(cl, skb->len, cur_time);
1712 if (realtime)
1713 cl->cl_cumul += skb->len;
1714
1715 if (cl->qdisc->q.qlen != 0) {
1716 if (cl->cl_flags & HFSC_RSC) {
1717 /* update ed */
1718 next_len = qdisc_peek_len(cl->qdisc);
1719 if (realtime)
1720 update_ed(cl, next_len);
1721 else
1722 update_d(cl, next_len);
1723 }
1724 } else {
1725 /* the class becomes passive */
1726 set_passive(cl);
1727 }
1728
1729 out:
1730 sch->flags &= ~TCQ_F_THROTTLED;
1731 sch->q.qlen--;
1732
1733 return skb;
1734 }
1735
1736 static int
1737 hfsc_requeue(struct sk_buff *skb, struct Qdisc *sch)
1738 {
1739 struct hfsc_sched *q = qdisc_priv(sch);
1740
1741 __skb_queue_head(&q->requeue, skb);
1742 sch->q.qlen++;
1743 sch->qstats.requeues++;
1744 return NET_XMIT_SUCCESS;
1745 }
1746
1747 static unsigned int
1748 hfsc_drop(struct Qdisc *sch)
1749 {
1750 struct hfsc_sched *q = qdisc_priv(sch);
1751 struct hfsc_class *cl;
1752 unsigned int len;
1753
1754 list_for_each_entry(cl, &q->droplist, dlist) {
1755 if (cl->qdisc->ops->drop != NULL &&
1756 (len = cl->qdisc->ops->drop(cl->qdisc)) > 0) {
1757 if (cl->qdisc->q.qlen == 0) {
1758 update_vf(cl, 0, 0);
1759 set_passive(cl);
1760 } else {
1761 list_move_tail(&cl->dlist, &q->droplist);
1762 }
1763 cl->qstats.drops++;
1764 sch->qstats.drops++;
1765 sch->q.qlen--;
1766 return len;
1767 }
1768 }
1769 return 0;
1770 }
1771
1772 static struct Qdisc_class_ops hfsc_class_ops = {
1773 .change = hfsc_change_class,
1774 .delete = hfsc_delete_class,
1775 .graft = hfsc_graft_class,
1776 .leaf = hfsc_class_leaf,
1777 .qlen_notify = hfsc_qlen_notify,
1778 .get = hfsc_get_class,
1779 .put = hfsc_put_class,
1780 .bind_tcf = hfsc_bind_tcf,
1781 .unbind_tcf = hfsc_unbind_tcf,
1782 .tcf_chain = hfsc_tcf_chain,
1783 .dump = hfsc_dump_class,
1784 .dump_stats = hfsc_dump_class_stats,
1785 .walk = hfsc_walk
1786 };
1787
1788 static struct Qdisc_ops hfsc_qdisc_ops = {
1789 .id = "hfsc",
1790 .init = hfsc_init_qdisc,
1791 .change = hfsc_change_qdisc,
1792 .reset = hfsc_reset_qdisc,
1793 .destroy = hfsc_destroy_qdisc,
1794 .dump = hfsc_dump_qdisc,
1795 .enqueue = hfsc_enqueue,
1796 .dequeue = hfsc_dequeue,
1797 .requeue = hfsc_requeue,
1798 .drop = hfsc_drop,
1799 .cl_ops = &hfsc_class_ops,
1800 .priv_size = sizeof(struct hfsc_sched),
1801 .owner = THIS_MODULE
1802 };
1803
1804 static int __init
1805 hfsc_init(void)
1806 {
1807 return register_qdisc(&hfsc_qdisc_ops);
1808 }
1809
1810 static void __exit
1811 hfsc_cleanup(void)
1812 {
1813 unregister_qdisc(&hfsc_qdisc_ops);
1814 }
1815
1816 MODULE_LICENSE("GPL");
1817 module_init(hfsc_init);
1818 module_exit(hfsc_cleanup);