altq_rio.c revision 1.4 1 /* $NetBSD: altq_rio.c,v 1.4 2001/11/12 23:14:22 lukem Exp $ */
2 /* $KAME: altq_rio.c,v 1.8 2000/12/14 08:12:46 thorpej Exp $ */
3
4 /*
5 * Copyright (C) 1998-2000
6 * Sony Computer Science Laboratories Inc. All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY SONY CSL AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL SONY CSL OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29 /*
30 * Copyright (c) 1990-1994 Regents of the University of California.
31 * All rights reserved.
32 *
33 * Redistribution and use in source and binary forms, with or without
34 * modification, are permitted provided that the following conditions
35 * are met:
36 * 1. Redistributions of source code must retain the above copyright
37 * notice, this list of conditions and the following disclaimer.
38 * 2. Redistributions in binary form must reproduce the above copyright
39 * notice, this list of conditions and the following disclaimer in the
40 * documentation and/or other materials provided with the distribution.
41 * 3. All advertising materials mentioning features or use of this software
42 * must display the following acknowledgement:
43 * This product includes software developed by the Computer Systems
44 * Engineering Group at Lawrence Berkeley Laboratory.
45 * 4. Neither the name of the University nor of the Laboratory may be used
46 * to endorse or promote products derived from this software without
47 * specific prior written permission.
48 *
49 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
50 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
51 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
52 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
53 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
54 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
55 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
56 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
57 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
58 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
59 * SUCH DAMAGE.
60 */
61
62 #include <sys/cdefs.h>
63 __KERNEL_RCSID(0, "$NetBSD: altq_rio.c,v 1.4 2001/11/12 23:14:22 lukem Exp $");
64
65 #if defined(__FreeBSD__) || defined(__NetBSD__)
66 #include "opt_altq.h"
67 #if (__FreeBSD__ != 2)
68 #include "opt_inet.h"
69 #ifdef __FreeBSD__
70 #include "opt_inet6.h"
71 #endif
72 #endif
73 #endif /* __FreeBSD__ || __NetBSD__ */
74 #ifdef ALTQ_RIO /* rio is enabled by ALTQ_RIO option in opt_altq.h */
75
76 #include <sys/param.h>
77 #include <sys/malloc.h>
78 #include <sys/mbuf.h>
79 #include <sys/socket.h>
80 #include <sys/sockio.h>
81 #include <sys/systm.h>
82 #include <sys/proc.h>
83 #include <sys/errno.h>
84 #include <sys/kernel.h>
85
86 #include <net/if.h>
87 #include <net/if_types.h>
88
89 #include <netinet/in.h>
90 #include <netinet/in_systm.h>
91 #include <netinet/ip.h>
92 #ifdef INET6
93 #include <netinet/ip6.h>
94 #endif
95
96 #include <altq/altq.h>
97 #include <altq/altq_conf.h>
98 #include <altq/altq_cdnr.h>
99 #include <altq/altq_red.h>
100 #include <altq/altq_rio.h>
101
102 /*
103 * RIO: RED with IN/OUT bit
104 * described in
105 * "Explicit Allocation of Best Effort Packet Delivery Service"
106 * David D. Clark and Wenjia Fang, MIT Lab for Computer Science
107 * http://diffserv.lcs.mit.edu/Papers/exp-alloc-ddc-wf.{ps,pdf}
108 *
109 * this implementation is extended to support more than 2 drop precedence
110 * values as described in RFC2597 (Assured Forwarding PHB Group).
111 *
112 */
113 /*
114 * AF DS (differentiated service) codepoints.
115 * (classes can be mapped to CBQ or H-FSC classes.)
116 *
117 * 0 1 2 3 4 5 6 7
118 * +---+---+---+---+---+---+---+---+
119 * | CLASS |DropPre| 0 | CU |
120 * +---+---+---+---+---+---+---+---+
121 *
122 * class 1: 001
123 * class 2: 010
124 * class 3: 011
125 * class 4: 100
126 *
127 * low drop prec: 01
128 * medium drop prec: 10
129 * high drop prec: 01
130 */
131
132 /* normal red parameters */
133 #define W_WEIGHT 512 /* inverse of weight of EWMA (511/512) */
134 /* q_weight = 0.00195 */
135
136 /* red parameters for a slow link */
137 #define W_WEIGHT_1 128 /* inverse of weight of EWMA (127/128) */
138 /* q_weight = 0.0078125 */
139
140 /* red parameters for a very slow link (e.g., dialup) */
141 #define W_WEIGHT_2 64 /* inverse of weight of EWMA (63/64) */
142 /* q_weight = 0.015625 */
143
144 /* fixed-point uses 12-bit decimal places */
145 #define FP_SHIFT 12 /* fixed-point shift */
146
147 /* red parameters for drop probability */
148 #define INV_P_MAX 10 /* inverse of max drop probability */
149 #define TH_MIN 5 /* min threshold */
150 #define TH_MAX 15 /* max threshold */
151
152 #define RIO_LIMIT 60 /* default max queue lenght */
153 #define RIO_STATS /* collect statistics */
154
155 #define TV_DELTA(a, b, delta) { \
156 register int xxs; \
157 \
158 delta = (a)->tv_usec - (b)->tv_usec; \
159 if ((xxs = (a)->tv_sec - (b)->tv_sec) != 0) { \
160 if (xxs < 0) { \
161 printf("rm_class: bogus time values"); \
162 delta = 60000000; \
163 } else if (xxs > 4) { \
164 if (xxs > 60) \
165 delta = 60000000; \
166 else \
167 delta += xxs * 1000000; \
168 } else while (xxs > 0) { \
169 delta += 1000000; \
170 xxs--; \
171 } \
172 } \
173 }
174
175 /* rio_list keeps all rio_queue_t's allocated. */
176 static rio_queue_t *rio_list = NULL;
177 /* default rio parameter values */
178 static struct redparams default_rio_params[RIO_NDROPPREC] = {
179 /* th_min, th_max, inv_pmax */
180 { TH_MAX * 2 + TH_MIN, TH_MAX * 3, INV_P_MAX }, /* low drop precedence */
181 { TH_MAX + TH_MIN, TH_MAX * 2, INV_P_MAX }, /* medium drop precedence */
182 { TH_MIN, TH_MAX, INV_P_MAX } /* high drop precedence */
183 };
184
185 /* internal function prototypes */
186 static int rio_enqueue __P((struct ifaltq *, struct mbuf *,
187 struct altq_pktattr *));
188 static struct mbuf *rio_dequeue __P((struct ifaltq *, int));
189 static int rio_request __P((struct ifaltq *, int, void *));
190 static int rio_detach __P((rio_queue_t *));
191 static int dscp2index __P((u_int8_t));
192
193 /*
194 * rio device interface
195 */
196 altqdev_decl(rio);
197
198 int
199 rioopen(dev, flag, fmt, p)
200 dev_t dev;
201 int flag, fmt;
202 struct proc *p;
203 {
204 /* everything will be done when the queueing scheme is attached. */
205 return 0;
206 }
207
208 int
209 rioclose(dev, flag, fmt, p)
210 dev_t dev;
211 int flag, fmt;
212 struct proc *p;
213 {
214 rio_queue_t *rqp;
215 int err, error = 0;
216
217 while ((rqp = rio_list) != NULL) {
218 /* destroy all */
219 err = rio_detach(rqp);
220 if (err != 0 && error == 0)
221 error = err;
222 }
223
224 return error;
225 }
226
227 int
228 rioioctl(dev, cmd, addr, flag, p)
229 dev_t dev;
230 ioctlcmd_t cmd;
231 caddr_t addr;
232 int flag;
233 struct proc *p;
234 {
235 rio_queue_t *rqp;
236 struct rio_interface *ifacep;
237 struct ifnet *ifp;
238 int error = 0;
239
240 /* check super-user privilege */
241 switch (cmd) {
242 case RIO_GETSTATS:
243 break;
244 default:
245 #if (__FreeBSD_version > 400000)
246 if ((error = suser(p)) != 0)
247 return (error);
248 #else
249 if ((error = suser(p->p_ucred, &p->p_acflag)) != 0)
250 return (error);
251 #endif
252 break;
253 }
254
255 switch (cmd) {
256
257 case RIO_ENABLE:
258 ifacep = (struct rio_interface *)addr;
259 if ((rqp = altq_lookup(ifacep->rio_ifname, ALTQT_RIO)) == NULL) {
260 error = EBADF;
261 break;
262 }
263 error = altq_enable(rqp->rq_ifq);
264 break;
265
266 case RIO_DISABLE:
267 ifacep = (struct rio_interface *)addr;
268 if ((rqp = altq_lookup(ifacep->rio_ifname, ALTQT_RIO)) == NULL) {
269 error = EBADF;
270 break;
271 }
272 error = altq_disable(rqp->rq_ifq);
273 break;
274
275 case RIO_IF_ATTACH:
276 ifp = ifunit(((struct rio_interface *)addr)->rio_ifname);
277 if (ifp == NULL) {
278 error = ENXIO;
279 break;
280 }
281
282 /* allocate and initialize rio_queue_t */
283 MALLOC(rqp, rio_queue_t *, sizeof(rio_queue_t), M_DEVBUF, M_WAITOK);
284 if (rqp == NULL) {
285 error = ENOMEM;
286 break;
287 }
288 bzero(rqp, sizeof(rio_queue_t));
289
290 MALLOC(rqp->rq_q, class_queue_t *, sizeof(class_queue_t),
291 M_DEVBUF, M_WAITOK);
292 if (rqp->rq_q == NULL) {
293 FREE(rqp, M_DEVBUF);
294 error = ENOMEM;
295 break;
296 }
297 bzero(rqp->rq_q, sizeof(class_queue_t));
298
299 rqp->rq_rio = rio_alloc(0, NULL, 0, 0);
300 if (rqp->rq_rio == NULL) {
301 FREE(rqp->rq_q, M_DEVBUF);
302 FREE(rqp, M_DEVBUF);
303 error = ENOMEM;
304 break;
305 }
306
307 rqp->rq_ifq = &ifp->if_snd;
308 qtail(rqp->rq_q) = NULL;
309 qlen(rqp->rq_q) = 0;
310 qlimit(rqp->rq_q) = RIO_LIMIT;
311 qtype(rqp->rq_q) = Q_RIO;
312
313 /*
314 * set RIO to this ifnet structure.
315 */
316 error = altq_attach(rqp->rq_ifq, ALTQT_RIO, rqp,
317 rio_enqueue, rio_dequeue, rio_request,
318 NULL, NULL);
319 if (error) {
320 rio_destroy(rqp->rq_rio);
321 FREE(rqp->rq_q, M_DEVBUF);
322 FREE(rqp, M_DEVBUF);
323 break;
324 }
325
326 /* add this state to the rio list */
327 rqp->rq_next = rio_list;
328 rio_list = rqp;
329 break;
330
331 case RIO_IF_DETACH:
332 ifacep = (struct rio_interface *)addr;
333 if ((rqp = altq_lookup(ifacep->rio_ifname, ALTQT_RIO)) == NULL) {
334 error = EBADF;
335 break;
336 }
337 error = rio_detach(rqp);
338 break;
339
340 case RIO_GETSTATS:
341 do {
342 struct rio_stats *q_stats;
343 rio_t *rp;
344 int i;
345
346 q_stats = (struct rio_stats *)addr;
347 if ((rqp = altq_lookup(q_stats->iface.rio_ifname,
348 ALTQT_RIO)) == NULL) {
349 error = EBADF;
350 break;
351 }
352
353 rp = rqp->rq_rio;
354
355 q_stats->q_limit = qlimit(rqp->rq_q);
356 q_stats->weight = rp->rio_weight;
357 q_stats->flags = rp->rio_flags;
358
359 for (i = 0; i < RIO_NDROPPREC; i++) {
360 q_stats->q_len[i] = rp->rio_precstate[i].qlen;
361 bcopy(&rp->q_stats[i], &q_stats->q_stats[i],
362 sizeof(struct redstats));
363 q_stats->q_stats[i].q_avg =
364 rp->rio_precstate[i].avg >> rp->rio_wshift;
365
366 q_stats->q_params[i].inv_pmax
367 = rp->rio_precstate[i].inv_pmax;
368 q_stats->q_params[i].th_min
369 = rp->rio_precstate[i].th_min;
370 q_stats->q_params[i].th_max
371 = rp->rio_precstate[i].th_max;
372 }
373 } while (0);
374 break;
375
376 case RIO_CONFIG:
377 do {
378 struct rio_conf *fc;
379 rio_t *new;
380 int s, limit, i;
381
382 fc = (struct rio_conf *)addr;
383 if ((rqp = altq_lookup(fc->iface.rio_ifname,
384 ALTQT_RIO)) == NULL) {
385 error = EBADF;
386 break;
387 }
388
389 new = rio_alloc(fc->rio_weight, &fc->q_params[0],
390 fc->rio_flags, fc->rio_pkttime);
391 if (new == NULL) {
392 error = ENOMEM;
393 break;
394 }
395
396 s = splnet();
397 _flushq(rqp->rq_q);
398 limit = fc->rio_limit;
399 if (limit < fc->q_params[RIO_NDROPPREC-1].th_max)
400 limit = fc->q_params[RIO_NDROPPREC-1].th_max;
401 qlimit(rqp->rq_q) = limit;
402
403 rio_destroy(rqp->rq_rio);
404 rqp->rq_rio = new;
405
406 splx(s);
407
408 /* write back new values */
409 fc->rio_limit = limit;
410 for (i = 0; i < RIO_NDROPPREC; i++) {
411 fc->q_params[i].inv_pmax =
412 rqp->rq_rio->rio_precstate[i].inv_pmax;
413 fc->q_params[i].th_min =
414 rqp->rq_rio->rio_precstate[i].th_min;
415 fc->q_params[i].th_max =
416 rqp->rq_rio->rio_precstate[i].th_max;
417 }
418 } while (0);
419 break;
420
421 case RIO_SETDEFAULTS:
422 do {
423 struct redparams *rp;
424 int i;
425
426 rp = (struct redparams *)addr;
427 for (i = 0; i < RIO_NDROPPREC; i++)
428 default_rio_params[i] = rp[i];
429 } while (0);
430 break;
431
432 default:
433 error = EINVAL;
434 break;
435 }
436
437 return error;
438 }
439
440 static int
441 rio_detach(rqp)
442 rio_queue_t *rqp;
443 {
444 rio_queue_t *tmp;
445 int error = 0;
446
447 if (ALTQ_IS_ENABLED(rqp->rq_ifq))
448 altq_disable(rqp->rq_ifq);
449
450 if ((error = altq_detach(rqp->rq_ifq)))
451 return (error);
452
453 if (rio_list == rqp)
454 rio_list = rqp->rq_next;
455 else {
456 for (tmp = rio_list; tmp != NULL; tmp = tmp->rq_next)
457 if (tmp->rq_next == rqp) {
458 tmp->rq_next = rqp->rq_next;
459 break;
460 }
461 if (tmp == NULL)
462 printf("rio_detach: no state found in rio_list!\n");
463 }
464
465 rio_destroy(rqp->rq_rio);
466 FREE(rqp->rq_q, M_DEVBUF);
467 FREE(rqp, M_DEVBUF);
468 return (error);
469 }
470
471 /*
472 * rio support routines
473 */
474 static int
475 rio_request(ifq, req, arg)
476 struct ifaltq *ifq;
477 int req;
478 void *arg;
479 {
480 rio_queue_t *rqp = (rio_queue_t *)ifq->altq_disc;
481
482 switch (req) {
483 case ALTRQ_PURGE:
484 _flushq(rqp->rq_q);
485 if (ALTQ_IS_ENABLED(ifq))
486 ifq->ifq_len = 0;
487 break;
488 }
489 return (0);
490 }
491
492
493 rio_t *
494 rio_alloc(weight, params, flags, pkttime)
495 int weight;
496 struct redparams *params;
497 int flags, pkttime;
498 {
499 rio_t *rp;
500 int w, i;
501 int npkts_per_sec;
502
503 MALLOC(rp, rio_t *, sizeof(rio_t), M_DEVBUF, M_WAITOK);
504 if (rp == NULL)
505 return (NULL);
506 bzero(rp, sizeof(rio_t));
507
508 rp->rio_flags = flags;
509 if (pkttime == 0)
510 /* default packet time: 1000 bytes / 10Mbps * 8 * 1000000 */
511 rp->rio_pkttime = 800;
512 else
513 rp->rio_pkttime = pkttime;
514
515 if (weight != 0)
516 rp->rio_weight = weight;
517 else {
518 /* use derfault */
519 rp->rio_weight = W_WEIGHT;
520
521 /* when the link is very slow, adjust red parameters */
522 npkts_per_sec = 1000000 / rp->rio_pkttime;
523 if (npkts_per_sec < 50) {
524 /* up to about 400Kbps */
525 rp->rio_weight = W_WEIGHT_2;
526 } else if (npkts_per_sec < 300) {
527 /* up to about 2.4Mbps */
528 rp->rio_weight = W_WEIGHT_1;
529 }
530 }
531
532 /* calculate wshift. weight must be power of 2 */
533 w = rp->rio_weight;
534 for (i = 0; w > 1; i++)
535 w = w >> 1;
536 rp->rio_wshift = i;
537 w = 1 << rp->rio_wshift;
538 if (w != rp->rio_weight) {
539 printf("invalid weight value %d for red! use %d\n",
540 rp->rio_weight, w);
541 rp->rio_weight = w;
542 }
543
544 /* allocate weight table */
545 rp->rio_wtab = wtab_alloc(rp->rio_weight);
546
547 for (i = 0; i < RIO_NDROPPREC; i++) {
548 struct dropprec_state *prec = &rp->rio_precstate[i];
549
550 prec->avg = 0;
551 prec->idle = 1;
552
553 if (params == NULL || params[i].inv_pmax == 0)
554 prec->inv_pmax = default_rio_params[i].inv_pmax;
555 else
556 prec->inv_pmax = params[i].inv_pmax;
557 if (params == NULL || params[i].th_min == 0)
558 prec->th_min = default_rio_params[i].th_min;
559 else
560 prec->th_min = params[i].th_min;
561 if (params == NULL || params[i].th_max == 0)
562 prec->th_max = default_rio_params[i].th_max;
563 else
564 prec->th_max = params[i].th_max;
565
566 /*
567 * th_min_s and th_max_s are scaled versions of th_min
568 * and th_max to be compared with avg.
569 */
570 prec->th_min_s = prec->th_min << (rp->rio_wshift + FP_SHIFT);
571 prec->th_max_s = prec->th_max << (rp->rio_wshift + FP_SHIFT);
572
573 /*
574 * precompute probability denominator
575 * probd = (2 * (TH_MAX-TH_MIN) / pmax) in fixed-point
576 */
577 prec->probd = (2 * (prec->th_max - prec->th_min)
578 * prec->inv_pmax) << FP_SHIFT;
579
580 microtime(&prec->last);
581 }
582
583 return (rp);
584 }
585
586 void
587 rio_destroy(rp)
588 rio_t *rp;
589 {
590 wtab_destroy(rp->rio_wtab);
591 FREE(rp, M_DEVBUF);
592 }
593
594 void
595 rio_getstats(rp, sp)
596 rio_t *rp;
597 struct redstats *sp;
598 {
599 int i;
600
601 for (i = 0; i < RIO_NDROPPREC; i++) {
602 bcopy(&rp->q_stats[i], sp, sizeof(struct redstats));
603 sp->q_avg = rp->rio_precstate[i].avg >> rp->rio_wshift;
604 sp++;
605 }
606 }
607
608 /*
609 * enqueue routine:
610 *
611 * returns: 0 when successfully queued.
612 * ENOBUFS when drop occurs.
613 */
614 static int
615 rio_enqueue(ifq, m, pktattr)
616 struct ifaltq *ifq;
617 struct mbuf *m;
618 struct altq_pktattr *pktattr;
619 {
620 rio_queue_t *rqp = (rio_queue_t *)ifq->altq_disc;
621 int error = 0;
622
623 if (rio_addq(rqp->rq_rio, rqp->rq_q, m, pktattr) == 0)
624 ifq->ifq_len++;
625 else
626 error = ENOBUFS;
627 return error;
628 }
629
630 #if (RIO_NDROPPREC == 3)
631 /*
632 * internally, a drop precedence value is converted to an index
633 * starting from 0.
634 */
635 static int
636 dscp2index(u_int8_t dscp)
637 {
638 int dpindex = dscp & AF_DROPPRECMASK;
639
640 if (dpindex == 0)
641 return (0);
642 return ((dpindex >> 3) - 1);
643 }
644 #endif
645
646 #if 1
647 /*
648 * kludge: when a packet is dequeued, we need to know its drop precedence
649 * in order to keep the queue length of each drop precedence.
650 * use m_pkthdr.rcvif to pass this info.
651 */
652 #define RIOM_SET_PRECINDEX(m, idx) \
653 do { (m)->m_pkthdr.rcvif = (struct ifnet *)((long)(idx)); } while (0)
654 #define RIOM_GET_PRECINDEX(m) \
655 ({ long idx; idx = (long)((m)->m_pkthdr.rcvif); \
656 (m)->m_pkthdr.rcvif = NULL; idx; })
657 #endif
658
659 int
660 rio_addq(rp, q, m, pktattr)
661 rio_t *rp;
662 class_queue_t *q;
663 struct mbuf *m;
664 struct altq_pktattr *pktattr;
665 {
666 int avg, droptype;
667 u_int8_t dsfield, odsfield;
668 int dpindex, i, n, t;
669 struct timeval now;
670 struct dropprec_state *prec;
671
672 dsfield = odsfield = read_dsfield(m, pktattr);
673 dpindex = dscp2index(dsfield);
674
675 /*
676 * update avg of the precedence states whose drop precedence
677 * is larger than or equal to the drop precedence of the packet
678 */
679 now.tv_sec = 0;
680 for (i = dpindex; i < RIO_NDROPPREC; i++) {
681 prec = &rp->rio_precstate[i];
682 avg = prec->avg;
683 if (prec->idle) {
684 prec->idle = 0;
685 if (now.tv_sec == 0)
686 microtime(&now);
687 t = (now.tv_sec - prec->last.tv_sec);
688 if (t > 60)
689 avg = 0;
690 else {
691 t = t * 1000000 +
692 (now.tv_usec - prec->last.tv_usec);
693 n = t / rp->rio_pkttime;
694 /* calculate (avg = (1 - Wq)^n * avg) */
695 if (n > 0)
696 avg = (avg >> FP_SHIFT) *
697 pow_w(rp->rio_wtab, n);
698 }
699 }
700
701 /* run estimator. (avg is scaled by WEIGHT in fixed-point) */
702 avg += (prec->qlen << FP_SHIFT) - (avg >> rp->rio_wshift);
703 prec->avg = avg; /* save the new value */
704 /*
705 * count keeps a tally of arriving traffic that has not
706 * been dropped.
707 */
708 prec->count++;
709 }
710
711 prec = &rp->rio_precstate[dpindex];
712 avg = prec->avg;
713
714 /* see if we drop early */
715 droptype = DTYPE_NODROP;
716 if (avg >= prec->th_min_s && prec->qlen > 1) {
717 if (avg >= prec->th_max_s) {
718 /* avg >= th_max: forced drop */
719 droptype = DTYPE_FORCED;
720 } else if (prec->old == 0) {
721 /* first exceeds th_min */
722 prec->count = 1;
723 prec->old = 1;
724 } else if (drop_early((avg - prec->th_min_s) >> rp->rio_wshift,
725 prec->probd, prec->count)) {
726 /* unforced drop by red */
727 droptype = DTYPE_EARLY;
728 }
729 } else {
730 /* avg < th_min */
731 prec->old = 0;
732 }
733
734 /*
735 * if the queue length hits the hard limit, it's a forced drop.
736 */
737 if (droptype == DTYPE_NODROP && qlen(q) >= qlimit(q))
738 droptype = DTYPE_FORCED;
739
740 if (droptype != DTYPE_NODROP) {
741 /* always drop incoming packet (as opposed to randomdrop) */
742 for (i = dpindex; i < RIO_NDROPPREC; i++)
743 rp->rio_precstate[i].count = 0;
744 #ifdef RIO_STATS
745 if (droptype == DTYPE_EARLY)
746 rp->q_stats[dpindex].drop_unforced++;
747 else
748 rp->q_stats[dpindex].drop_forced++;
749 PKTCNTR_ADD(&rp->q_stats[dpindex].drop_cnt, m_pktlen(m));
750 #endif
751 m_freem(m);
752 return (-1);
753 }
754
755 for (i = dpindex; i < RIO_NDROPPREC; i++)
756 rp->rio_precstate[i].qlen++;
757
758 /* save drop precedence index in mbuf hdr */
759 RIOM_SET_PRECINDEX(m, dpindex);
760
761 if (rp->rio_flags & RIOF_CLEARDSCP)
762 dsfield &= ~DSCP_MASK;
763
764 if (dsfield != odsfield)
765 write_dsfield(m, pktattr, dsfield);
766
767 _addq(q, m);
768
769 #ifdef RIO_STATS
770 PKTCNTR_ADD(&rp->q_stats[dpindex].xmit_cnt, m_pktlen(m));
771 #endif
772 return (0);
773 }
774
775 /*
776 * dequeue routine:
777 * must be called in splnet.
778 *
779 * returns: mbuf dequeued.
780 * NULL when no packet is available in the queue.
781 */
782
783 static struct mbuf *
784 rio_dequeue(ifq, op)
785 struct ifaltq *ifq;
786 int op;
787 {
788 rio_queue_t *rqp = (rio_queue_t *)ifq->altq_disc;
789 struct mbuf *m = NULL;
790
791 if (op == ALTDQ_POLL)
792 return qhead(rqp->rq_q);
793
794 m = rio_getq(rqp->rq_rio, rqp->rq_q);
795 if (m != NULL)
796 ifq->ifq_len--;
797 return m;
798 }
799
800 struct mbuf *
801 rio_getq(rp, q)
802 rio_t *rp;
803 class_queue_t *q;
804 {
805 struct mbuf *m;
806 int dpindex, i;
807
808 if ((m = _getq(q)) == NULL)
809 return NULL;
810
811 dpindex = RIOM_GET_PRECINDEX(m);
812 for (i = dpindex; i < RIO_NDROPPREC; i++) {
813 if (--rp->rio_precstate[i].qlen == 0) {
814 if (rp->rio_precstate[i].idle == 0) {
815 rp->rio_precstate[i].idle = 1;
816 microtime(&rp->rio_precstate[i].last);
817 }
818 }
819 }
820 return (m);
821 }
822
823 #ifdef KLD_MODULE
824
825 static struct altqsw rio_sw =
826 {"rio", rioopen, rioclose, rioioctl};
827
828 ALTQ_MODULE(altq_rio, ALTQT_RIO, &rio_sw);
829
830 #endif /* KLD_MODULE */
831
832 #endif /* ALTQ_RIO */
833