?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
initial commit with v2.6.9
[linux-2.6.9-moxart.git] / net / sched / sch_gred.c
blob375c6c2fb996933fc4b2555cf568a31de7b327df
1 /*
2 * net/sched/sch_gred.c Generic Random Early Detection queue.
3 *
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License
7 * as published by the Free Software Foundation; either version
8 * 2 of the License, or (at your option) any later version.
9 *
10 * Authors: J Hadi Salim (hadi@cyberus.ca) 1998-2002
11 *
12 * 991129: - Bug fix with grio mode
13 * - a better sing. AvgQ mode with Grio(WRED)
14 * - A finer grained VQ dequeue based on sugestion
15 * from Ren Liu
16 * - More error checks
17 *
18 *
19 *
20 * For all the glorious comments look at Alexey's sch_red.c
21 */
22
23 #include <linux/config.h>
24 #include <linux/module.h>
25 #include <asm/uaccess.h>
26 #include <asm/system.h>
27 #include <asm/bitops.h>
28 #include <linux/types.h>
29 #include <linux/kernel.h>
30 #include <linux/sched.h>
31 #include <linux/string.h>
32 #include <linux/mm.h>
33 #include <linux/socket.h>
34 #include <linux/sockios.h>
35 #include <linux/in.h>
36 #include <linux/errno.h>
37 #include <linux/interrupt.h>
38 #include <linux/if_ether.h>
39 #include <linux/inet.h>
40 #include <linux/netdevice.h>
41 #include <linux/etherdevice.h>
42 #include <linux/notifier.h>
43 #include <net/ip.h>
44 #include <net/route.h>
45 #include <linux/skbuff.h>
46 #include <net/sock.h>
47 #include <net/pkt_sched.h>
48
49 #if 1 /* control */
50 #define DPRINTK(format,args...) printk(KERN_DEBUG format,##args)
51 #else
52 #define DPRINTK(format,args...)
53 #endif
54
55 #if 0 /* data */
56 #define D2PRINTK(format,args...) printk(KERN_DEBUG format,##args)
57 #else
58 #define D2PRINTK(format,args...)
59 #endif
60
61 struct gred_sched_data;
62 struct gred_sched;
63
64 struct gred_sched_data
65 {
66 /* Parameters */
67 u32 limit; /* HARD maximal queue length */
68 u32 qth_min; /* Min average length threshold: A scaled */
69 u32 qth_max; /* Max average length threshold: A scaled */
70 u32 DP; /* the drop pramaters */
71 char Wlog; /* log(W) */
72 char Plog; /* random number bits */
73 u32 Scell_max;
74 u32 Rmask;
75 u32 bytesin; /* bytes seen on virtualQ so far*/
76 u32 packetsin; /* packets seen on virtualQ so far*/
77 u32 backlog; /* bytes on the virtualQ */
78 u32 forced; /* packets dropped for exceeding limits */
79 u32 early; /* packets dropped as a warning */
80 u32 other; /* packets dropped by invoking drop() */
81 u32 pdrop; /* packets dropped because we exceeded physical queue limits */
82 char Scell_log;
83 u8 Stab[256];
84 u8 prio; /* the prio of this vq */
85
86 /* Variables */
87 unsigned long qave; /* Average queue length: A scaled */
88 int qcount; /* Packets since last random number generation */
89 u32 qR; /* Cached random number */
90
91 psched_time_t qidlestart; /* Start of idle period */
92 };
93
94 struct gred_sched
95 {
96 struct gred_sched_data *tab[MAX_DPs];
97 u32 DPs;
98 u32 def;
99 u8 initd;
100 u8 grio;
101 u8 eqp;
102 };
103
104 static int
105 gred_enqueue(struct sk_buff *skb, struct Qdisc* sch)
106 {
107 psched_time_t now;
108 struct gred_sched_data *q=NULL;
109 struct gred_sched *t= qdisc_priv(sch);
110 unsigned long qave=0;
111 int i=0;
112
113 if (!t->initd && skb_queue_len(&sch->q) < (sch->dev->tx_queue_len ? : 1)) {
114 D2PRINTK("NO GRED Queues setup yet! Enqueued anyway\n");
115 goto do_enqueue;
116 }
117
118
119 if ( ((skb->tc_index&0xf) > (t->DPs -1)) || !(q=t->tab[skb->tc_index&0xf])) {
120 printk("GRED: setting to default (%d)\n ",t->def);
121 if (!(q=t->tab[t->def])) {
122 DPRINTK("GRED: setting to default FAILED! dropping!! "
123 "(%d)\n ", t->def);
124 goto drop;
125 }
126 /* fix tc_index? --could be controvesial but needed for
127 requeueing */
128 skb->tc_index=(skb->tc_index&0xfffffff0) | t->def;
129 }
130
131 D2PRINTK("gred_enqueue virtualQ 0x%x classid %x backlog %d "
132 "general backlog %d\n",skb->tc_index&0xf,sch->handle,q->backlog,
133 sch->stats.backlog);
134 /* sum up all the qaves of prios <= to ours to get the new qave*/
135 if (!t->eqp && t->grio) {
136 for (i=0;i<t->DPs;i++) {
137 if ((!t->tab[i]) || (i==q->DP))
138 continue;
139
140 if ((t->tab[i]->prio < q->prio) && (PSCHED_IS_PASTPERFECT(t->tab[i]->qidlestart)))
141 qave +=t->tab[i]->qave;
142 }
143
144 }
145
146 q->packetsin++;
147 q->bytesin+=skb->len;
148
149 if (t->eqp && t->grio) {
150 qave=0;
151 q->qave=t->tab[t->def]->qave;
152 q->qidlestart=t->tab[t->def]->qidlestart;
153 }
154
155 if (!PSCHED_IS_PASTPERFECT(q->qidlestart)) {
156 long us_idle;
157 PSCHED_GET_TIME(now);
158 us_idle = PSCHED_TDIFF_SAFE(now, q->qidlestart, q->Scell_max);
159 PSCHED_SET_PASTPERFECT(q->qidlestart);
160
161 q->qave >>= q->Stab[(us_idle>>q->Scell_log)&0xFF];
162 } else {
163 if (t->eqp) {
164 q->qave += sch->stats.backlog - (q->qave >> q->Wlog);
165 } else {
166 q->qave += q->backlog - (q->qave >> q->Wlog);
167 }
168
169 }
170
171
172 if (t->eqp && t->grio)
173 t->tab[t->def]->qave=q->qave;
174
175 if ((q->qave+qave) < q->qth_min) {
176 q->qcount = -1;
177 enqueue:
178 if (q->backlog + skb->len <= q->limit) {
179 q->backlog += skb->len;
180 do_enqueue:
181 __skb_queue_tail(&sch->q, skb);
182 sch->stats.backlog += skb->len;
183 sch->stats.bytes += skb->len;
184 sch->stats.packets++;
185 return 0;
186 } else {
187 q->pdrop++;
188 }
189
190 drop:
191 kfree_skb(skb);
192 sch->stats.drops++;
193 return NET_XMIT_DROP;
194 }
195 if ((q->qave+qave) >= q->qth_max) {
196 q->qcount = -1;
197 sch->stats.overlimits++;
198 q->forced++;
199 goto drop;
200 }
201 if (++q->qcount) {
202 if ((((qave+q->qave) - q->qth_min)>>q->Wlog)*q->qcount < q->qR)
203 goto enqueue;
204 q->qcount = 0;
205 q->qR = net_random()&q->Rmask;
206 sch->stats.overlimits++;
207 q->early++;
208 goto drop;
209 }
210 q->qR = net_random()&q->Rmask;
211 goto enqueue;
212 }
213
214 static int
215 gred_requeue(struct sk_buff *skb, struct Qdisc* sch)
216 {
217 struct gred_sched_data *q;
218 struct gred_sched *t= qdisc_priv(sch);
219 q= t->tab[(skb->tc_index&0xf)];
220 /* error checking here -- probably unnecessary */
221 PSCHED_SET_PASTPERFECT(q->qidlestart);
222
223 __skb_queue_head(&sch->q, skb);
224 sch->stats.backlog += skb->len;
225 q->backlog += skb->len;
226 return 0;
227 }
228
229 static struct sk_buff *
230 gred_dequeue(struct Qdisc* sch)
231 {
232 struct sk_buff *skb;
233 struct gred_sched_data *q;
234 struct gred_sched *t= qdisc_priv(sch);
235
236 skb = __skb_dequeue(&sch->q);
237 if (skb) {
238 sch->stats.backlog -= skb->len;
239 q= t->tab[(skb->tc_index&0xf)];
240 if (q) {
241 q->backlog -= skb->len;
242 if (!q->backlog && !t->eqp)
243 PSCHED_GET_TIME(q->qidlestart);
244 } else {
245 D2PRINTK("gred_dequeue: skb has bad tcindex %x\n",skb->tc_index&0xf);
246 }
247 return skb;
248 }
249
250 if (t->eqp) {
251 q= t->tab[t->def];
252 if (!q)
253 D2PRINTK("no default VQ set: Results will be "
254 "screwed up\n");
255 else
256 PSCHED_GET_TIME(q->qidlestart);
257 }
258
259 return NULL;
260 }
261
262 static unsigned int gred_drop(struct Qdisc* sch)
263 {
264 struct sk_buff *skb;
265
266 struct gred_sched_data *q;
267 struct gred_sched *t= qdisc_priv(sch);
268
269 skb = __skb_dequeue_tail(&sch->q);
270 if (skb) {
271 unsigned int len = skb->len;
272 sch->stats.backlog -= len;
273 sch->stats.drops++;
274 q= t->tab[(skb->tc_index&0xf)];
275 if (q) {
276 q->backlog -= len;
277 q->other++;
278 if (!q->backlog && !t->eqp)
279 PSCHED_GET_TIME(q->qidlestart);
280 } else {
281 D2PRINTK("gred_dequeue: skb has bad tcindex %x\n",skb->tc_index&0xf);
282 }
283
284 kfree_skb(skb);
285 return len;
286 }
287
288 q=t->tab[t->def];
289 if (!q) {
290 D2PRINTK("no default VQ set: Results might be screwed up\n");
291 return 0;
292 }
293
294 PSCHED_GET_TIME(q->qidlestart);
295 return 0;
296
297 }
298
299 static void gred_reset(struct Qdisc* sch)
300 {
301 int i;
302 struct gred_sched_data *q;
303 struct gred_sched *t= qdisc_priv(sch);
304
305 __skb_queue_purge(&sch->q);
306
307 sch->stats.backlog = 0;
308
309 for (i=0;i<t->DPs;i++) {
310 q= t->tab[i];
311 if (!q)
312 continue;
313 PSCHED_SET_PASTPERFECT(q->qidlestart);
314 q->qave = 0;
315 q->qcount = -1;
316 q->backlog = 0;
317 q->other=0;
318 q->forced=0;
319 q->pdrop=0;
320 q->early=0;
321 }
322 }
323
324 static int gred_change(struct Qdisc *sch, struct rtattr *opt)
325 {
326 struct gred_sched *table = qdisc_priv(sch);
327 struct gred_sched_data *q;
328 struct tc_gred_qopt *ctl;
329 struct tc_gred_sopt *sopt;
330 struct rtattr *tb[TCA_GRED_STAB];
331 struct rtattr *tb2[TCA_GRED_DPS];
332 int i;
333
334 if (opt == NULL ||
335 rtattr_parse(tb, TCA_GRED_STAB, RTA_DATA(opt), RTA_PAYLOAD(opt)) )
336 return -EINVAL;
337
338 if (tb[TCA_GRED_PARMS-1] == 0 && tb[TCA_GRED_STAB-1] == 0) {
339 rtattr_parse(tb2, TCA_GRED_DPS, RTA_DATA(opt),
340 RTA_PAYLOAD(opt));
341
342 if (tb2[TCA_GRED_DPS-1] == 0)
343 return -EINVAL;
344
345 sopt = RTA_DATA(tb2[TCA_GRED_DPS-1]);
346 table->DPs=sopt->DPs;
347 table->def=sopt->def_DP;
348 table->grio=sopt->grio;
349 table->initd=0;
350 /* probably need to clear all the table DP entries as well */
351 return 0;
352 }
353
354
355 if (!table->DPs || tb[TCA_GRED_PARMS-1] == 0 || tb[TCA_GRED_STAB-1] == 0 ||
356 RTA_PAYLOAD(tb[TCA_GRED_PARMS-1]) < sizeof(*ctl) ||
357 RTA_PAYLOAD(tb[TCA_GRED_STAB-1]) < 256)
358 return -EINVAL;
359
360 ctl = RTA_DATA(tb[TCA_GRED_PARMS-1]);
361 if (ctl->DP > MAX_DPs-1 ) {
362 /* misbehaving is punished! Put in the default drop probability */
363 DPRINTK("\nGRED: DP %u not in the proper range fixed. New DP "
364 "set to default at %d\n",ctl->DP,table->def);
365 ctl->DP=table->def;
366 }
367
368 if (table->tab[ctl->DP] == NULL) {
369 table->tab[ctl->DP]=kmalloc(sizeof(struct gred_sched_data),
370 GFP_KERNEL);
371 if (NULL == table->tab[ctl->DP])
372 return -ENOMEM;
373 memset(table->tab[ctl->DP], 0, (sizeof(struct gred_sched_data)));
374 }
375 q= table->tab[ctl->DP];
376
377 if (table->grio) {
378 if (ctl->prio <=0) {
379 if (table->def && table->tab[table->def]) {
380 DPRINTK("\nGRED: DP %u does not have a prio"
381 "setting default to %d\n",ctl->DP,
382 table->tab[table->def]->prio);
383 q->prio=table->tab[table->def]->prio;
384 } else {
385 DPRINTK("\nGRED: DP %u does not have a prio"
386 " setting default to 8\n",ctl->DP);
387 q->prio=8;
388 }
389 } else {
390 q->prio=ctl->prio;
391 }
392 } else {
393 q->prio=8;
394 }
395
396
397 q->DP=ctl->DP;
398 q->Wlog = ctl->Wlog;
399 q->Plog = ctl->Plog;
400 q->limit = ctl->limit;
401 q->Scell_log = ctl->Scell_log;
402 q->Rmask = ctl->Plog < 32 ? ((1<<ctl->Plog) - 1) : ~0UL;
403 q->Scell_max = (255<<q->Scell_log);
404 q->qth_min = ctl->qth_min<<ctl->Wlog;
405 q->qth_max = ctl->qth_max<<ctl->Wlog;
406 q->qave=0;
407 q->backlog=0;
408 q->qcount = -1;
409 q->other=0;
410 q->forced=0;
411 q->pdrop=0;
412 q->early=0;
413
414 PSCHED_SET_PASTPERFECT(q->qidlestart);
415 memcpy(q->Stab, RTA_DATA(tb[TCA_GRED_STAB-1]), 256);
416
417 if ( table->initd && table->grio) {
418 /* this looks ugly but it's not in the fast path */
419 for (i=0;i<table->DPs;i++) {
420 if ((!table->tab[i]) || (i==q->DP) )
421 continue;
422 if (table->tab[i]->prio == q->prio ){
423 /* WRED mode detected */
424 table->eqp=1;
425 break;
426 }
427 }
428 }
429
430 if (!table->initd) {
431 table->initd=1;
432 /*
433 the first entry also goes into the default until
434 over-written
435 */
436
437 if (table->tab[table->def] == NULL) {
438 table->tab[table->def]=
439 kmalloc(sizeof(struct gred_sched_data), GFP_KERNEL);
440 if (NULL == table->tab[table->def])
441 return -ENOMEM;
442
443 memset(table->tab[table->def], 0,
444 (sizeof(struct gred_sched_data)));
445 }
446 q= table->tab[table->def];
447 q->DP=table->def;
448 q->Wlog = ctl->Wlog;
449 q->Plog = ctl->Plog;
450 q->limit = ctl->limit;
451 q->Scell_log = ctl->Scell_log;
452 q->Rmask = ctl->Plog < 32 ? ((1<<ctl->Plog) - 1) : ~0UL;
453 q->Scell_max = (255<<q->Scell_log);
454 q->qth_min = ctl->qth_min<<ctl->Wlog;
455 q->qth_max = ctl->qth_max<<ctl->Wlog;
456
457 if (table->grio)
458 q->prio=table->tab[ctl->DP]->prio;
459 else
460 q->prio=8;
461
462 q->qcount = -1;
463 PSCHED_SET_PASTPERFECT(q->qidlestart);
464 memcpy(q->Stab, RTA_DATA(tb[TCA_GRED_STAB-1]), 256);
465 }
466 return 0;
467
468 }
469
470 static int gred_init(struct Qdisc *sch, struct rtattr *opt)
471 {
472 struct gred_sched *table = qdisc_priv(sch);
473 struct tc_gred_sopt *sopt;
474 struct rtattr *tb[TCA_GRED_STAB];
475 struct rtattr *tb2[TCA_GRED_DPS];
476
477 if (opt == NULL ||
478 rtattr_parse(tb, TCA_GRED_STAB, RTA_DATA(opt), RTA_PAYLOAD(opt)) )
479 return -EINVAL;
480
481 if (tb[TCA_GRED_PARMS-1] == 0 && tb[TCA_GRED_STAB-1] == 0) {
482 rtattr_parse(tb2, TCA_GRED_DPS, RTA_DATA(opt),RTA_PAYLOAD(opt));
483
484 if (tb2[TCA_GRED_DPS-1] == 0)
485 return -EINVAL;
486
487 sopt = RTA_DATA(tb2[TCA_GRED_DPS-1]);
488 table->DPs=sopt->DPs;
489 table->def=sopt->def_DP;
490 table->grio=sopt->grio;
491 table->initd=0;
492 return 0;
493 }
494
495 DPRINTK("\n GRED_INIT error!\n");
496 return -EINVAL;
497 }
498
499 static int gred_dump(struct Qdisc *sch, struct sk_buff *skb)
500 {
501 unsigned long qave;
502 struct rtattr *rta;
503 struct tc_gred_qopt *opt = NULL ;
504 struct tc_gred_qopt *dst;
505 struct gred_sched *table = qdisc_priv(sch);
506 struct gred_sched_data *q;
507 int i;
508 unsigned char *b = skb->tail;
509
510 rta = (struct rtattr*)b;
511 RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
512
513 opt=kmalloc(sizeof(struct tc_gred_qopt)*MAX_DPs, GFP_KERNEL);
514
515 if (opt == NULL) {
516 DPRINTK("gred_dump:failed to malloc for %Zd\n",
517 sizeof(struct tc_gred_qopt)*MAX_DPs);
518 goto rtattr_failure;
519 }
520
521 memset(opt, 0, (sizeof(struct tc_gred_qopt))*table->DPs);
522
523 if (!table->initd) {
524 DPRINTK("NO GRED Queues setup!\n");
525 }
526
527 for (i=0;i<MAX_DPs;i++) {
528 dst= &opt[i];
529 q= table->tab[i];
530
531 if (!q) {
532 /* hack -- fix at some point with proper message
533 This is how we indicate to tc that there is no VQ
534 at this DP */
535
536 dst->DP=MAX_DPs+i;
537 continue;
538 }
539
540 dst->limit=q->limit;
541 dst->qth_min=q->qth_min>>q->Wlog;
542 dst->qth_max=q->qth_max>>q->Wlog;
543 dst->DP=q->DP;
544 dst->backlog=q->backlog;
545 if (q->qave) {
546 if (table->eqp && table->grio) {
547 q->qidlestart=table->tab[table->def]->qidlestart;
548 q->qave=table->tab[table->def]->qave;
549 }
550 if (!PSCHED_IS_PASTPERFECT(q->qidlestart)) {
551 long idle;
552 psched_time_t now;
553 PSCHED_GET_TIME(now);
554 idle = PSCHED_TDIFF_SAFE(now, q->qidlestart, q->Scell_max);
555 qave = q->qave >> q->Stab[(idle>>q->Scell_log)&0xFF];
556 dst->qave = qave >> q->Wlog;
557
558 } else {
559 dst->qave = q->qave >> q->Wlog;
560 }
561 } else {
562 dst->qave = 0;
563 }
564
565
566 dst->Wlog = q->Wlog;
567 dst->Plog = q->Plog;
568 dst->Scell_log = q->Scell_log;
569 dst->other = q->other;
570 dst->forced = q->forced;
571 dst->early = q->early;
572 dst->pdrop = q->pdrop;
573 dst->prio = q->prio;
574 dst->packets=q->packetsin;
575 dst->bytesin=q->bytesin;
576 }
577
578 RTA_PUT(skb, TCA_GRED_PARMS, sizeof(struct tc_gred_qopt)*MAX_DPs, opt);
579 rta->rta_len = skb->tail - b;
580
581 kfree(opt);
582 return skb->len;
583
584 rtattr_failure:
585 if (opt)
586 kfree(opt);
587 DPRINTK("gred_dump: FAILURE!!!!\n");
588
589 /* also free the opt struct here */
590 skb_trim(skb, b - skb->data);
591 return -1;
592 }
593
594 static void gred_destroy(struct Qdisc *sch)
595 {
596 struct gred_sched *table = qdisc_priv(sch);
597 int i;
598
599 for (i = 0;i < table->DPs; i++) {
600 if (table->tab[i])
601 kfree(table->tab[i]);
602 }
603 }
604
605 static struct Qdisc_ops gred_qdisc_ops = {
606 .next = NULL,
607 .cl_ops = NULL,
608 .id = "gred",
609 .priv_size = sizeof(struct gred_sched),
610 .enqueue = gred_enqueue,
611 .dequeue = gred_dequeue,
612 .requeue = gred_requeue,
613 .drop = gred_drop,
614 .init = gred_init,
615 .reset = gred_reset,
616 .destroy = gred_destroy,
617 .change = gred_change,
618 .dump = gred_dump,
619 .owner = THIS_MODULE,
620 };
621
622 static int __init gred_module_init(void)
623 {
624 return register_qdisc(&gred_qdisc_ops);
625 }
626 static void __exit gred_module_exit(void)
627 {
628 unregister_qdisc(&gred_qdisc_ops);
629 }
630 module_init(gred_module_init)
631 module_exit(gred_module_exit)
632 MODULE_LICENSE("GPL");
MOXA 2.6.9 from sdlinux-moxaart.tgz