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-rw-r--r--net/sched/sch_gred.c630
1 files changed, 630 insertions, 0 deletions
diff --git a/net/sched/sch_gred.c b/net/sched/sch_gred.c
new file mode 100644
index 000000000000..25c171c32715
--- /dev/null
+++ b/net/sched/sch_gred.c
@@ -0,0 +1,630 @@
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 <linux/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
61struct gred_sched_data;
62struct gred_sched;
63
64struct 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
94struct 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
104static int
105gred_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->qstats.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->qstats.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;
177enqueue:
178 if (q->backlog + skb->len <= q->limit) {
179 q->backlog += skb->len;
180do_enqueue:
181 __skb_queue_tail(&sch->q, skb);
182 sch->qstats.backlog += skb->len;
183 sch->bstats.bytes += skb->len;
184 sch->bstats.packets++;
185 return 0;
186 } else {
187 q->pdrop++;
188 }
189
190drop:
191 kfree_skb(skb);
192 sch->qstats.drops++;
193 return NET_XMIT_DROP;
194 }
195 if ((q->qave+qave) >= q->qth_max) {
196 q->qcount = -1;
197 sch->qstats.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->qstats.overlimits++;
207 q->early++;
208 goto drop;
209 }
210 q->qR = net_random()&q->Rmask;
211 goto enqueue;
212}
213
214static int
215gred_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->qstats.backlog += skb->len;
225 sch->qstats.requeues++;
226 q->backlog += skb->len;
227 return 0;
228}
229
230static struct sk_buff *
231gred_dequeue(struct Qdisc* sch)
232{
233 struct sk_buff *skb;
234 struct gred_sched_data *q;
235 struct gred_sched *t= qdisc_priv(sch);
236
237 skb = __skb_dequeue(&sch->q);
238 if (skb) {
239 sch->qstats.backlog -= skb->len;
240 q= t->tab[(skb->tc_index&0xf)];
241 if (q) {
242 q->backlog -= skb->len;
243 if (!q->backlog && !t->eqp)
244 PSCHED_GET_TIME(q->qidlestart);
245 } else {
246 D2PRINTK("gred_dequeue: skb has bad tcindex %x\n",skb->tc_index&0xf);
247 }
248 return skb;
249 }
250
251 if (t->eqp) {
252 q= t->tab[t->def];
253 if (!q)
254 D2PRINTK("no default VQ set: Results will be "
255 "screwed up\n");
256 else
257 PSCHED_GET_TIME(q->qidlestart);
258 }
259
260 return NULL;
261}
262
263static unsigned int gred_drop(struct Qdisc* sch)
264{
265 struct sk_buff *skb;
266
267 struct gred_sched_data *q;
268 struct gred_sched *t= qdisc_priv(sch);
269
270 skb = __skb_dequeue_tail(&sch->q);
271 if (skb) {
272 unsigned int len = skb->len;
273 sch->qstats.backlog -= len;
274 sch->qstats.drops++;
275 q= t->tab[(skb->tc_index&0xf)];
276 if (q) {
277 q->backlog -= len;
278 q->other++;
279 if (!q->backlog && !t->eqp)
280 PSCHED_GET_TIME(q->qidlestart);
281 } else {
282 D2PRINTK("gred_dequeue: skb has bad tcindex %x\n",skb->tc_index&0xf);
283 }
284
285 kfree_skb(skb);
286 return len;
287 }
288
289 q=t->tab[t->def];
290 if (!q) {
291 D2PRINTK("no default VQ set: Results might be screwed up\n");
292 return 0;
293 }
294
295 PSCHED_GET_TIME(q->qidlestart);
296 return 0;
297
298}
299
300static void gred_reset(struct Qdisc* sch)
301{
302 int i;
303 struct gred_sched_data *q;
304 struct gred_sched *t= qdisc_priv(sch);
305
306 __skb_queue_purge(&sch->q);
307
308 sch->qstats.backlog = 0;
309
310 for (i=0;i<t->DPs;i++) {
311 q= t->tab[i];
312 if (!q)
313 continue;
314 PSCHED_SET_PASTPERFECT(q->qidlestart);
315 q->qave = 0;
316 q->qcount = -1;
317 q->backlog = 0;
318 q->other=0;
319 q->forced=0;
320 q->pdrop=0;
321 q->early=0;
322 }
323}
324
325static int gred_change(struct Qdisc *sch, struct rtattr *opt)
326{
327 struct gred_sched *table = qdisc_priv(sch);
328 struct gred_sched_data *q;
329 struct tc_gred_qopt *ctl;
330 struct tc_gred_sopt *sopt;
331 struct rtattr *tb[TCA_GRED_STAB];
332 struct rtattr *tb2[TCA_GRED_DPS];
333 int i;
334
335 if (opt == NULL || rtattr_parse_nested(tb, TCA_GRED_STAB, opt))
336 return -EINVAL;
337
338 if (tb[TCA_GRED_PARMS-1] == 0 && tb[TCA_GRED_STAB-1] == 0) {
339 rtattr_parse_nested(tb2, TCA_GRED_DPS, opt);
340
341 if (tb2[TCA_GRED_DPS-1] == 0)
342 return -EINVAL;
343
344 sopt = RTA_DATA(tb2[TCA_GRED_DPS-1]);
345 table->DPs=sopt->DPs;
346 table->def=sopt->def_DP;
347 table->grio=sopt->grio;
348 table->initd=0;
349 /* probably need to clear all the table DP entries as well */
350 return 0;
351 }
352
353
354 if (!table->DPs || tb[TCA_GRED_PARMS-1] == 0 || tb[TCA_GRED_STAB-1] == 0 ||
355 RTA_PAYLOAD(tb[TCA_GRED_PARMS-1]) < sizeof(*ctl) ||
356 RTA_PAYLOAD(tb[TCA_GRED_STAB-1]) < 256)
357 return -EINVAL;
358
359 ctl = RTA_DATA(tb[TCA_GRED_PARMS-1]);
360 if (ctl->DP > MAX_DPs-1 ) {
361 /* misbehaving is punished! Put in the default drop probability */
362 DPRINTK("\nGRED: DP %u not in the proper range fixed. New DP "
363 "set to default at %d\n",ctl->DP,table->def);
364 ctl->DP=table->def;
365 }
366
367 if (table->tab[ctl->DP] == NULL) {
368 table->tab[ctl->DP]=kmalloc(sizeof(struct gred_sched_data),
369 GFP_KERNEL);
370 if (NULL == table->tab[ctl->DP])
371 return -ENOMEM;
372 memset(table->tab[ctl->DP], 0, (sizeof(struct gred_sched_data)));
373 }
374 q= table->tab[ctl->DP];
375
376 if (table->grio) {
377 if (ctl->prio <=0) {
378 if (table->def && table->tab[table->def]) {
379 DPRINTK("\nGRED: DP %u does not have a prio"
380 "setting default to %d\n",ctl->DP,
381 table->tab[table->def]->prio);
382 q->prio=table->tab[table->def]->prio;
383 } else {
384 DPRINTK("\nGRED: DP %u does not have a prio"
385 " setting default to 8\n",ctl->DP);
386 q->prio=8;
387 }
388 } else {
389 q->prio=ctl->prio;
390 }
391 } else {
392 q->prio=8;
393 }
394
395
396 q->DP=ctl->DP;
397 q->Wlog = ctl->Wlog;
398 q->Plog = ctl->Plog;
399 q->limit = ctl->limit;
400 q->Scell_log = ctl->Scell_log;
401 q->Rmask = ctl->Plog < 32 ? ((1<<ctl->Plog) - 1) : ~0UL;
402 q->Scell_max = (255<<q->Scell_log);
403 q->qth_min = ctl->qth_min<<ctl->Wlog;
404 q->qth_max = ctl->qth_max<<ctl->Wlog;
405 q->qave=0;
406 q->backlog=0;
407 q->qcount = -1;
408 q->other=0;
409 q->forced=0;
410 q->pdrop=0;
411 q->early=0;
412
413 PSCHED_SET_PASTPERFECT(q->qidlestart);
414 memcpy(q->Stab, RTA_DATA(tb[TCA_GRED_STAB-1]), 256);
415
416 if ( table->initd && table->grio) {
417 /* this looks ugly but it's not in the fast path */
418 for (i=0;i<table->DPs;i++) {
419 if ((!table->tab[i]) || (i==q->DP) )
420 continue;
421 if (table->tab[i]->prio == q->prio ){
422 /* WRED mode detected */
423 table->eqp=1;
424 break;
425 }
426 }
427 }
428
429 if (!table->initd) {
430 table->initd=1;
431 /*
432 the first entry also goes into the default until
433 over-written
434 */
435
436 if (table->tab[table->def] == NULL) {
437 table->tab[table->def]=
438 kmalloc(sizeof(struct gred_sched_data), GFP_KERNEL);
439 if (NULL == table->tab[table->def])
440 return -ENOMEM;
441
442 memset(table->tab[table->def], 0,
443 (sizeof(struct gred_sched_data)));
444 }
445 q= table->tab[table->def];
446 q->DP=table->def;
447 q->Wlog = ctl->Wlog;
448 q->Plog = ctl->Plog;
449 q->limit = ctl->limit;
450 q->Scell_log = ctl->Scell_log;
451 q->Rmask = ctl->Plog < 32 ? ((1<<ctl->Plog) - 1) : ~0UL;
452 q->Scell_max = (255<<q->Scell_log);
453 q->qth_min = ctl->qth_min<<ctl->Wlog;
454 q->qth_max = ctl->qth_max<<ctl->Wlog;
455
456 if (table->grio)
457 q->prio=table->tab[ctl->DP]->prio;
458 else
459 q->prio=8;
460
461 q->qcount = -1;
462 PSCHED_SET_PASTPERFECT(q->qidlestart);
463 memcpy(q->Stab, RTA_DATA(tb[TCA_GRED_STAB-1]), 256);
464 }
465 return 0;
466
467}
468
469static int gred_init(struct Qdisc *sch, struct rtattr *opt)
470{
471 struct gred_sched *table = qdisc_priv(sch);
472 struct tc_gred_sopt *sopt;
473 struct rtattr *tb[TCA_GRED_STAB];
474 struct rtattr *tb2[TCA_GRED_DPS];
475
476 if (opt == NULL || rtattr_parse_nested(tb, TCA_GRED_STAB, opt))
477 return -EINVAL;
478
479 if (tb[TCA_GRED_PARMS-1] == 0 && tb[TCA_GRED_STAB-1] == 0) {
480 rtattr_parse_nested(tb2, TCA_GRED_DPS, opt);
481
482 if (tb2[TCA_GRED_DPS-1] == 0)
483 return -EINVAL;
484
485 sopt = RTA_DATA(tb2[TCA_GRED_DPS-1]);
486 table->DPs=sopt->DPs;
487 table->def=sopt->def_DP;
488 table->grio=sopt->grio;
489 table->initd=0;
490 return 0;
491 }
492
493 DPRINTK("\n GRED_INIT error!\n");
494 return -EINVAL;
495}
496
497static int gred_dump(struct Qdisc *sch, struct sk_buff *skb)
498{
499 unsigned long qave;
500 struct rtattr *rta;
501 struct tc_gred_qopt *opt = NULL ;
502 struct tc_gred_qopt *dst;
503 struct gred_sched *table = qdisc_priv(sch);
504 struct gred_sched_data *q;
505 int i;
506 unsigned char *b = skb->tail;
507
508 rta = (struct rtattr*)b;
509 RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
510
511 opt=kmalloc(sizeof(struct tc_gred_qopt)*MAX_DPs, GFP_KERNEL);
512
513 if (opt == NULL) {
514 DPRINTK("gred_dump:failed to malloc for %Zd\n",
515 sizeof(struct tc_gred_qopt)*MAX_DPs);
516 goto rtattr_failure;
517 }
518
519 memset(opt, 0, (sizeof(struct tc_gred_qopt))*table->DPs);
520
521 if (!table->initd) {
522 DPRINTK("NO GRED Queues setup!\n");
523 }
524
525 for (i=0;i<MAX_DPs;i++) {
526 dst= &opt[i];
527 q= table->tab[i];
528
529 if (!q) {
530 /* hack -- fix at some point with proper message
531 This is how we indicate to tc that there is no VQ
532 at this DP */
533
534 dst->DP=MAX_DPs+i;
535 continue;
536 }
537
538 dst->limit=q->limit;
539 dst->qth_min=q->qth_min>>q->Wlog;
540 dst->qth_max=q->qth_max>>q->Wlog;
541 dst->DP=q->DP;
542 dst->backlog=q->backlog;
543 if (q->qave) {
544 if (table->eqp && table->grio) {
545 q->qidlestart=table->tab[table->def]->qidlestart;
546 q->qave=table->tab[table->def]->qave;
547 }
548 if (!PSCHED_IS_PASTPERFECT(q->qidlestart)) {
549 long idle;
550 psched_time_t now;
551 PSCHED_GET_TIME(now);
552 idle = PSCHED_TDIFF_SAFE(now, q->qidlestart, q->Scell_max);
553 qave = q->qave >> q->Stab[(idle>>q->Scell_log)&0xFF];
554 dst->qave = qave >> q->Wlog;
555
556 } else {
557 dst->qave = q->qave >> q->Wlog;
558 }
559 } else {
560 dst->qave = 0;
561 }
562
563
564 dst->Wlog = q->Wlog;
565 dst->Plog = q->Plog;
566 dst->Scell_log = q->Scell_log;
567 dst->other = q->other;
568 dst->forced = q->forced;
569 dst->early = q->early;
570 dst->pdrop = q->pdrop;
571 dst->prio = q->prio;
572 dst->packets=q->packetsin;
573 dst->bytesin=q->bytesin;
574 }
575
576 RTA_PUT(skb, TCA_GRED_PARMS, sizeof(struct tc_gred_qopt)*MAX_DPs, opt);
577 rta->rta_len = skb->tail - b;
578
579 kfree(opt);
580 return skb->len;
581
582rtattr_failure:
583 if (opt)
584 kfree(opt);
585 DPRINTK("gred_dump: FAILURE!!!!\n");
586
587/* also free the opt struct here */
588 skb_trim(skb, b - skb->data);
589 return -1;
590}
591
592static void gred_destroy(struct Qdisc *sch)
593{
594 struct gred_sched *table = qdisc_priv(sch);
595 int i;
596
597 for (i = 0;i < table->DPs; i++) {
598 if (table->tab[i])
599 kfree(table->tab[i]);
600 }
601}
602
603static struct Qdisc_ops gred_qdisc_ops = {
604 .next = NULL,
605 .cl_ops = NULL,
606 .id = "gred",
607 .priv_size = sizeof(struct gred_sched),
608 .enqueue = gred_enqueue,
609 .dequeue = gred_dequeue,
610 .requeue = gred_requeue,
611 .drop = gred_drop,
612 .init = gred_init,
613 .reset = gred_reset,
614 .destroy = gred_destroy,
615 .change = gred_change,
616 .dump = gred_dump,
617 .owner = THIS_MODULE,
618};
619
620static int __init gred_module_init(void)
621{
622 return register_qdisc(&gred_qdisc_ops);
623}
624static void __exit gred_module_exit(void)
625{
626 unregister_qdisc(&gred_qdisc_ops);
627}
628module_init(gred_module_init)
629module_exit(gred_module_exit)
630MODULE_LICENSE("GPL");
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-06 22:24:01 -0500