[PKT_SCHED]: GRED: Cleanup dumping
[linux-2.6.git] / net / sched / sch_gred.c
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
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 enum {
95         GRED_WRED_MODE = 1,
96         GRED_RIO_MODE,
97 };
98
99 struct gred_sched
100 {
101         struct gred_sched_data *tab[MAX_DPs];
102         unsigned long   flags;
103         u32             DPs;   
104         u32             def; 
105         u8              initd; 
106 };
107
108 static inline int gred_wred_mode(struct gred_sched *table)
109 {
110         return test_bit(GRED_WRED_MODE, &table->flags);
111 }
112
113 static inline void gred_enable_wred_mode(struct gred_sched *table)
114 {
115         __set_bit(GRED_WRED_MODE, &table->flags);
116 }
117
118 static inline void gred_disable_wred_mode(struct gred_sched *table)
119 {
120         __clear_bit(GRED_WRED_MODE, &table->flags);
121 }
122
123 static inline int gred_rio_mode(struct gred_sched *table)
124 {
125         return test_bit(GRED_RIO_MODE, &table->flags);
126 }
127
128 static inline void gred_enable_rio_mode(struct gred_sched *table)
129 {
130         __set_bit(GRED_RIO_MODE, &table->flags);
131 }
132
133 static inline void gred_disable_rio_mode(struct gred_sched *table)
134 {
135         __clear_bit(GRED_RIO_MODE, &table->flags);
136 }
137
138 static inline int gred_wred_mode_check(struct Qdisc *sch)
139 {
140         struct gred_sched *table = qdisc_priv(sch);
141         int i;
142
143         /* Really ugly O(n^2) but shouldn't be necessary too frequent. */
144         for (i = 0; i < table->DPs; i++) {
145                 struct gred_sched_data *q = table->tab[i];
146                 int n;
147
148                 if (q == NULL)
149                         continue;
150
151                 for (n = 0; n < table->DPs; n++)
152                         if (table->tab[n] && table->tab[n] != q &&
153                             table->tab[n]->prio == q->prio)
154                                 return 1;
155         }
156
157         return 0;
158 }
159
160 static int
161 gred_enqueue(struct sk_buff *skb, struct Qdisc* sch)
162 {
163         psched_time_t now;
164         struct gred_sched_data *q=NULL;
165         struct gred_sched *t= qdisc_priv(sch);
166         unsigned long   qave=0; 
167         int i=0;
168
169         if (!t->initd && skb_queue_len(&sch->q) < (sch->dev->tx_queue_len ? : 1)) {
170                 D2PRINTK("NO GRED Queues setup yet! Enqueued anyway\n");
171                 goto do_enqueue;
172         }
173
174
175         if ( ((skb->tc_index&0xf) > (t->DPs -1)) || !(q=t->tab[skb->tc_index&0xf])) {
176                 printk("GRED: setting to default (%d)\n ",t->def);
177                 if (!(q=t->tab[t->def])) {
178                         DPRINTK("GRED: setting to default FAILED! dropping!! "
179                             "(%d)\n ", t->def);
180                         goto drop;
181                 }
182                 /* fix tc_index? --could be controvesial but needed for
183                    requeueing */
184                 skb->tc_index=(skb->tc_index&0xfffffff0) | t->def;
185         }
186
187         D2PRINTK("gred_enqueue virtualQ 0x%x classid %x backlog %d "
188             "general backlog %d\n",skb->tc_index&0xf,sch->handle,q->backlog,
189             sch->qstats.backlog);
190         /* sum up all the qaves of prios <= to ours to get the new qave*/
191         if (!gred_wred_mode(t) && gred_rio_mode(t)) {
192                 for (i=0;i<t->DPs;i++) {
193                         if ((!t->tab[i]) || (i==q->DP)) 
194                                 continue; 
195                                 
196                         if ((t->tab[i]->prio < q->prio) && (PSCHED_IS_PASTPERFECT(t->tab[i]->qidlestart)))
197                                 qave +=t->tab[i]->qave;
198                 }
199                         
200         }
201
202         q->packetsin++;
203         q->bytesin+=skb->len;
204
205         if (gred_wred_mode(t)) {
206                 qave=0;
207                 q->qave=t->tab[t->def]->qave;
208                 q->qidlestart=t->tab[t->def]->qidlestart;
209         }
210
211         if (!PSCHED_IS_PASTPERFECT(q->qidlestart)) {
212                 long us_idle;
213                 PSCHED_GET_TIME(now);
214                 us_idle = PSCHED_TDIFF_SAFE(now, q->qidlestart, q->Scell_max);
215                 PSCHED_SET_PASTPERFECT(q->qidlestart);
216
217                 q->qave >>= q->Stab[(us_idle>>q->Scell_log)&0xFF];
218         } else {
219                 if (gred_wred_mode(t)) {
220                         q->qave += sch->qstats.backlog - (q->qave >> q->Wlog);
221                 } else {
222                         q->qave += q->backlog - (q->qave >> q->Wlog);
223                 }
224
225         }
226         
227
228         if (gred_wred_mode(t))
229                 t->tab[t->def]->qave=q->qave;
230
231         if ((q->qave+qave) < q->qth_min) {
232                 q->qcount = -1;
233 enqueue:
234                 if (q->backlog + skb->len <= q->limit) {
235                         q->backlog += skb->len;
236 do_enqueue:
237                         __skb_queue_tail(&sch->q, skb);
238                         sch->qstats.backlog += skb->len;
239                         sch->bstats.bytes += skb->len;
240                         sch->bstats.packets++;
241                         return 0;
242                 } else {
243                         q->pdrop++;
244                 }
245
246 drop:
247                 kfree_skb(skb);
248                 sch->qstats.drops++;
249                 return NET_XMIT_DROP;
250         }
251         if ((q->qave+qave) >= q->qth_max) {
252                 q->qcount = -1;
253                 sch->qstats.overlimits++;
254                 q->forced++;
255                 goto drop;
256         }
257         if (++q->qcount) {
258                 if ((((qave+q->qave) - q->qth_min)>>q->Wlog)*q->qcount < q->qR)
259                         goto enqueue;
260                 q->qcount = 0;
261                 q->qR = net_random()&q->Rmask;
262                 sch->qstats.overlimits++;
263                 q->early++;
264                 goto drop;
265         }
266         q->qR = net_random()&q->Rmask;
267         goto enqueue;
268 }
269
270 static int
271 gred_requeue(struct sk_buff *skb, struct Qdisc* sch)
272 {
273         struct gred_sched_data *q;
274         struct gred_sched *t= qdisc_priv(sch);
275         q= t->tab[(skb->tc_index&0xf)];
276 /* error checking here -- probably unnecessary */
277         PSCHED_SET_PASTPERFECT(q->qidlestart);
278
279         __skb_queue_head(&sch->q, skb);
280         sch->qstats.backlog += skb->len;
281         sch->qstats.requeues++;
282         q->backlog += skb->len;
283         return 0;
284 }
285
286 static struct sk_buff *
287 gred_dequeue(struct Qdisc* sch)
288 {
289         struct sk_buff *skb;
290         struct gred_sched_data *q;
291         struct gred_sched *t= qdisc_priv(sch);
292
293         skb = __skb_dequeue(&sch->q);
294         if (skb) {
295                 sch->qstats.backlog -= skb->len;
296                 q= t->tab[(skb->tc_index&0xf)];
297                 if (q) {
298                         q->backlog -= skb->len;
299                         if (!q->backlog && !gred_wred_mode(t))
300                                 PSCHED_GET_TIME(q->qidlestart);
301                 } else {
302                         D2PRINTK("gred_dequeue: skb has bad tcindex %x\n",skb->tc_index&0xf); 
303                 }
304                 return skb;
305         }
306
307         if (gred_wred_mode(t)) {
308                         q= t->tab[t->def];
309                         if (!q) 
310                                 D2PRINTK("no default VQ set: Results will be "
311                                        "screwed up\n");
312                         else
313                                 PSCHED_GET_TIME(q->qidlestart);
314         }
315
316         return NULL;
317 }
318
319 static unsigned int gred_drop(struct Qdisc* sch)
320 {
321         struct sk_buff *skb;
322
323         struct gred_sched_data *q;
324         struct gred_sched *t= qdisc_priv(sch);
325
326         skb = __skb_dequeue_tail(&sch->q);
327         if (skb) {
328                 unsigned int len = skb->len;
329                 sch->qstats.backlog -= len;
330                 sch->qstats.drops++;
331                 q= t->tab[(skb->tc_index&0xf)];
332                 if (q) {
333                         q->backlog -= len;
334                         q->other++;
335                         if (!q->backlog && !gred_wred_mode(t))
336                                 PSCHED_GET_TIME(q->qidlestart);
337                 } else {
338                         D2PRINTK("gred_dequeue: skb has bad tcindex %x\n",skb->tc_index&0xf); 
339                 }
340
341                 kfree_skb(skb);
342                 return len;
343         }
344
345         q=t->tab[t->def];
346         if (!q) {
347                 D2PRINTK("no default VQ set: Results might be screwed up\n");
348                 return 0;
349         }
350
351         PSCHED_GET_TIME(q->qidlestart);
352         return 0;
353
354 }
355
356 static void gred_reset(struct Qdisc* sch)
357 {
358         int i;
359         struct gred_sched_data *q;
360         struct gred_sched *t= qdisc_priv(sch);
361
362         __skb_queue_purge(&sch->q);
363
364         sch->qstats.backlog = 0;
365
366         for (i=0;i<t->DPs;i++) {
367                 q= t->tab[i];
368                 if (!q) 
369                         continue; 
370                 PSCHED_SET_PASTPERFECT(q->qidlestart);
371                 q->qave = 0;
372                 q->qcount = -1;
373                 q->backlog = 0;
374                 q->other=0;
375                 q->forced=0;
376                 q->pdrop=0;
377                 q->early=0;
378         }
379 }
380
381 static int gred_change(struct Qdisc *sch, struct rtattr *opt)
382 {
383         struct gred_sched *table = qdisc_priv(sch);
384         struct gred_sched_data *q;
385         struct tc_gred_qopt *ctl;
386         struct tc_gred_sopt *sopt;
387         struct rtattr *tb[TCA_GRED_STAB];
388         struct rtattr *tb2[TCA_GRED_DPS];
389
390         if (opt == NULL || rtattr_parse_nested(tb, TCA_GRED_STAB, opt))
391                 return -EINVAL;
392
393         if (tb[TCA_GRED_PARMS-1] == 0 && tb[TCA_GRED_STAB-1] == 0) {
394                 rtattr_parse_nested(tb2, TCA_GRED_DPS, opt);
395
396             if (tb2[TCA_GRED_DPS-1] == 0) 
397                         return -EINVAL;
398
399                 sopt = RTA_DATA(tb2[TCA_GRED_DPS-1]);
400                 table->DPs=sopt->DPs;   
401                 table->def=sopt->def_DP; 
402
403                 if (sopt->grio) {
404                         gred_enable_rio_mode(table);
405                         gred_disable_wred_mode(table);
406                         if (gred_wred_mode_check(sch))
407                                 gred_enable_wred_mode(table);
408                 } else {
409                         gred_disable_rio_mode(table);
410                         gred_disable_wred_mode(table);
411                 }
412
413                 table->initd=0;
414                 /* probably need to clear all the table DP entries as well */
415                 return 0;
416             }
417
418
419         if (!table->DPs || tb[TCA_GRED_PARMS-1] == 0 || tb[TCA_GRED_STAB-1] == 0 ||
420                 RTA_PAYLOAD(tb[TCA_GRED_PARMS-1]) < sizeof(*ctl) ||
421                 RTA_PAYLOAD(tb[TCA_GRED_STAB-1]) < 256)
422                         return -EINVAL;
423
424         ctl = RTA_DATA(tb[TCA_GRED_PARMS-1]);
425         if (ctl->DP > MAX_DPs-1 ) {
426                 /* misbehaving is punished! Put in the default drop probability */
427                 DPRINTK("\nGRED: DP %u not in  the proper range fixed. New DP "
428                         "set to default at %d\n",ctl->DP,table->def);
429                 ctl->DP=table->def;
430         }
431         
432         if (table->tab[ctl->DP] == NULL) {
433                 table->tab[ctl->DP]=kmalloc(sizeof(struct gred_sched_data),
434                                             GFP_KERNEL);
435                 if (NULL == table->tab[ctl->DP])
436                         return -ENOMEM;
437                 memset(table->tab[ctl->DP], 0, (sizeof(struct gred_sched_data)));
438         }
439         q= table->tab[ctl->DP]; 
440
441         if (gred_rio_mode(table)) {
442                 if (ctl->prio <=0) {
443                         if (table->def && table->tab[table->def]) {
444                                 DPRINTK("\nGRED: DP %u does not have a prio"
445                                         "setting default to %d\n",ctl->DP,
446                                         table->tab[table->def]->prio);
447                                 q->prio=table->tab[table->def]->prio;
448                         } else { 
449                                 DPRINTK("\nGRED: DP %u does not have a prio"
450                                         " setting default to 8\n",ctl->DP);
451                                 q->prio=8;
452                         }
453                 } else {
454                         q->prio=ctl->prio;
455                 }
456         } else {
457                 q->prio=8;
458         }
459
460
461         q->DP=ctl->DP;
462         q->Wlog = ctl->Wlog;
463         q->Plog = ctl->Plog;
464         q->limit = ctl->limit;
465         q->Scell_log = ctl->Scell_log;
466         q->Rmask = ctl->Plog < 32 ? ((1<<ctl->Plog) - 1) : ~0UL;
467         q->Scell_max = (255<<q->Scell_log);
468         q->qth_min = ctl->qth_min<<ctl->Wlog;
469         q->qth_max = ctl->qth_max<<ctl->Wlog;
470         q->qave=0;
471         q->backlog=0;
472         q->qcount = -1;
473         q->other=0;
474         q->forced=0;
475         q->pdrop=0;
476         q->early=0;
477
478         PSCHED_SET_PASTPERFECT(q->qidlestart);
479         memcpy(q->Stab, RTA_DATA(tb[TCA_GRED_STAB-1]), 256);
480
481         if (gred_rio_mode(table)) {
482                 gred_disable_wred_mode(table);
483                 if (gred_wred_mode_check(sch))
484                         gred_enable_wred_mode(table);
485         }
486
487         if (!table->initd) {
488                 table->initd=1;
489                 /* 
490                 the first entry also goes into the default until
491                 over-written 
492                 */
493
494                 if (table->tab[table->def] == NULL) {
495                         table->tab[table->def]=
496                                 kmalloc(sizeof(struct gred_sched_data), GFP_KERNEL);
497                         if (NULL == table->tab[table->def])
498                                 return -ENOMEM;
499
500                         memset(table->tab[table->def], 0,
501                                (sizeof(struct gred_sched_data)));
502                 }
503                 q= table->tab[table->def]; 
504                 q->DP=table->def;
505                 q->Wlog = ctl->Wlog;
506                 q->Plog = ctl->Plog;
507                 q->limit = ctl->limit;
508                 q->Scell_log = ctl->Scell_log;
509                 q->Rmask = ctl->Plog < 32 ? ((1<<ctl->Plog) - 1) : ~0UL;
510                 q->Scell_max = (255<<q->Scell_log);
511                 q->qth_min = ctl->qth_min<<ctl->Wlog;
512                 q->qth_max = ctl->qth_max<<ctl->Wlog;
513
514                 if (gred_rio_mode(table))
515                         q->prio=table->tab[ctl->DP]->prio;
516                 else
517                         q->prio=8;
518
519                 q->qcount = -1;
520                 PSCHED_SET_PASTPERFECT(q->qidlestart);
521                 memcpy(q->Stab, RTA_DATA(tb[TCA_GRED_STAB-1]), 256);
522         }
523         return 0;
524
525 }
526
527 static int gred_init(struct Qdisc *sch, struct rtattr *opt)
528 {
529         struct gred_sched *table = qdisc_priv(sch);
530         struct tc_gred_sopt *sopt;
531         struct rtattr *tb[TCA_GRED_STAB];
532         struct rtattr *tb2[TCA_GRED_DPS];
533
534         if (opt == NULL || rtattr_parse_nested(tb, TCA_GRED_STAB, opt))
535                 return -EINVAL;
536
537         if (tb[TCA_GRED_PARMS-1] == 0 && tb[TCA_GRED_STAB-1] == 0) {
538                 rtattr_parse_nested(tb2, TCA_GRED_DPS, opt);
539
540             if (tb2[TCA_GRED_DPS-1] == 0) 
541                         return -EINVAL;
542
543                 sopt = RTA_DATA(tb2[TCA_GRED_DPS-1]);
544                 table->DPs=sopt->DPs;   
545                 table->def=sopt->def_DP; 
546
547                 if (sopt->grio)
548                         gred_enable_rio_mode(table);
549                 else
550                         gred_disable_rio_mode(table);
551
552                 table->initd=0;
553                 return 0;
554         }
555
556         DPRINTK("\n GRED_INIT error!\n");
557         return -EINVAL;
558 }
559
560 static int gred_dump(struct Qdisc *sch, struct sk_buff *skb)
561 {
562         struct gred_sched *table = qdisc_priv(sch);
563         struct rtattr *parms, *opts = NULL;
564         int i;
565
566         opts = RTA_NEST(skb, TCA_OPTIONS);
567         parms = RTA_NEST(skb, TCA_GRED_PARMS);
568
569         for (i = 0; i < MAX_DPs; i++) {
570                 struct gred_sched_data *q = table->tab[i];
571                 struct tc_gred_qopt opt;
572
573                 memset(&opt, 0, sizeof(opt));
574
575                 if (!q) {
576                         /* hack -- fix at some point with proper message
577                            This is how we indicate to tc that there is no VQ
578                            at this DP */
579
580                         opt.DP = MAX_DPs + i;
581                         goto append_opt;
582                 }
583
584                 opt.limit       = q->limit;
585                 opt.DP          = q->DP;
586                 opt.backlog     = q->backlog;
587                 opt.prio        = q->prio;
588                 opt.qth_min     = q->qth_min >> q->Wlog;
589                 opt.qth_max     = q->qth_max >> q->Wlog;
590                 opt.Wlog        = q->Wlog;
591                 opt.Plog        = q->Plog;
592                 opt.Scell_log   = q->Scell_log;
593                 opt.other       = q->other;
594                 opt.early       = q->early;
595                 opt.forced      = q->forced;
596                 opt.pdrop       = q->pdrop;
597                 opt.packets     = q->packetsin;
598                 opt.bytesin     = q->bytesin;
599
600                 if (q->qave) {
601                         if (gred_wred_mode(table)) {
602                                 q->qidlestart=table->tab[table->def]->qidlestart;
603                                 q->qave=table->tab[table->def]->qave;
604                         }
605                         if (!PSCHED_IS_PASTPERFECT(q->qidlestart)) {
606                                 long idle;
607                                 unsigned long qave;
608                                 psched_time_t now;
609                                 PSCHED_GET_TIME(now);
610                                 idle = PSCHED_TDIFF_SAFE(now, q->qidlestart, q->Scell_max);
611                                 qave  = q->qave >> q->Stab[(idle>>q->Scell_log)&0xFF];
612                                 opt.qave = qave >> q->Wlog;
613
614                         } else {
615                                 opt.qave = q->qave >> q->Wlog;
616                         }
617                 }
618
619 append_opt:
620                 RTA_APPEND(skb, sizeof(opt), &opt);
621         }
622
623         RTA_NEST_END(skb, parms);
624
625         return RTA_NEST_END(skb, opts);
626
627 rtattr_failure:
628         return RTA_NEST_CANCEL(skb, opts);
629 }
630
631 static void gred_destroy(struct Qdisc *sch)
632 {
633         struct gred_sched *table = qdisc_priv(sch);
634         int i;
635
636         for (i = 0;i < table->DPs; i++) {
637                 if (table->tab[i])
638                         kfree(table->tab[i]);
639         }
640 }
641
642 static struct Qdisc_ops gred_qdisc_ops = {
643         .next           =       NULL,
644         .cl_ops         =       NULL,
645         .id             =       "gred",
646         .priv_size      =       sizeof(struct gred_sched),
647         .enqueue        =       gred_enqueue,
648         .dequeue        =       gred_dequeue,
649         .requeue        =       gred_requeue,
650         .drop           =       gred_drop,
651         .init           =       gred_init,
652         .reset          =       gred_reset,
653         .destroy        =       gred_destroy,
654         .change         =       gred_change,
655         .dump           =       gred_dump,
656         .owner          =       THIS_MODULE,
657 };
658
659 static int __init gred_module_init(void)
660 {
661         return register_qdisc(&gred_qdisc_ops);
662 }
663 static void __exit gred_module_exit(void) 
664 {
665         unregister_qdisc(&gred_qdisc_ops);
666 }
667 module_init(gred_module_init)
668 module_exit(gred_module_exit)
669 MODULE_LICENSE("GPL");