1 /*
2 * Copyright (c) 2007 Pawel Jakub Dawidek <[email protected]>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * Links to Illumos.org for more information on kstat function:
27 * [1] https://illumos.org/man/1M/kstat
28 * [2] https://illumos.org/man/9f/kstat_create
29 */
30
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
33
34 #include <sys/types.h>
35 #include <sys/param.h>
36 #include <sys/kernel.h>
37 #include <sys/systm.h>
38 #include <sys/malloc.h>
39 #include <sys/sysctl.h>
40 #include <sys/kstat.h>
41 #include <sys/sbuf.h>
42
43 static MALLOC_DEFINE(M_KSTAT, "kstat_data", "Kernel statistics");
44
45 SYSCTL_ROOT_NODE(OID_AUTO, kstat, CTLFLAG_RW, 0, "Kernel statistics");
46
47 void
__kstat_set_raw_ops(kstat_t * ksp,int (* headers)(char * buf,size_t size),int (* data)(char * buf,size_t size,void * data),void * (* addr)(kstat_t * ksp,loff_t index))48 __kstat_set_raw_ops(kstat_t *ksp,
49 int (*headers)(char *buf, size_t size),
50 int (*data)(char *buf, size_t size, void *data),
51 void *(*addr)(kstat_t *ksp, loff_t index))
52 {
53 ksp->ks_raw_ops.headers = headers;
54 ksp->ks_raw_ops.data = data;
55 ksp->ks_raw_ops.addr = addr;
56 }
57
58 void
__kstat_set_seq_raw_ops(kstat_t * ksp,int (* headers)(struct seq_file * f),int (* data)(char * buf,size_t size,void * data),void * (* addr)(kstat_t * ksp,loff_t index))59 __kstat_set_seq_raw_ops(kstat_t *ksp,
60 int (*headers)(struct seq_file *f),
61 int (*data)(char *buf, size_t size, void *data),
62 void *(*addr)(kstat_t *ksp, loff_t index))
63 {
64 ksp->ks_raw_ops.seq_headers = headers;
65 ksp->ks_raw_ops.data = data;
66 ksp->ks_raw_ops.addr = addr;
67 }
68
69 static int
kstat_default_update(kstat_t * ksp,int rw)70 kstat_default_update(kstat_t *ksp, int rw)
71 {
72 ASSERT(ksp != NULL);
73
74 if (rw == KSTAT_WRITE)
75 return (EACCES);
76
77 return (0);
78 }
79
80 static int
kstat_resize_raw(kstat_t * ksp)81 kstat_resize_raw(kstat_t *ksp)
82 {
83 if (ksp->ks_raw_bufsize == KSTAT_RAW_MAX)
84 return (ENOMEM);
85
86 free(ksp->ks_raw_buf, M_TEMP);
87 ksp->ks_raw_bufsize = MIN(ksp->ks_raw_bufsize * 2, KSTAT_RAW_MAX);
88 ksp->ks_raw_buf = malloc(ksp->ks_raw_bufsize, M_TEMP, M_WAITOK);
89
90 return (0);
91 }
92
93 static void *
kstat_raw_default_addr(kstat_t * ksp,loff_t n)94 kstat_raw_default_addr(kstat_t *ksp, loff_t n)
95 {
96 if (n == 0)
97 return (ksp->ks_data);
98 return (NULL);
99 }
100
101 static int
kstat_sysctl(SYSCTL_HANDLER_ARGS)102 kstat_sysctl(SYSCTL_HANDLER_ARGS)
103 {
104 kstat_t *ksp = arg1;
105 kstat_named_t *ksent;
106 uint64_t val;
107
108 ksent = ksp->ks_data;
109 /* Select the correct element */
110 ksent += arg2;
111 /* Update the aggsums before reading */
112 (void) ksp->ks_update(ksp, KSTAT_READ);
113 val = ksent->value.ui64;
114
115 return (sysctl_handle_64(oidp, &val, 0, req));
116 }
117
118 static int
kstat_sysctl_string(SYSCTL_HANDLER_ARGS)119 kstat_sysctl_string(SYSCTL_HANDLER_ARGS)
120 {
121 kstat_t *ksp = arg1;
122 kstat_named_t *ksent = ksp->ks_data;
123 char *val;
124 uint32_t len = 0;
125
126 /* Select the correct element */
127 ksent += arg2;
128 /* Update the aggsums before reading */
129 (void) ksp->ks_update(ksp, KSTAT_READ);
130 val = KSTAT_NAMED_STR_PTR(ksent);
131 len = KSTAT_NAMED_STR_BUFLEN(ksent);
132 val[len-1] = '\0';
133
134 return (sysctl_handle_string(oidp, val, len, req));
135 }
136
137 static int
kstat_sysctl_io(SYSCTL_HANDLER_ARGS)138 kstat_sysctl_io(SYSCTL_HANDLER_ARGS)
139 {
140 struct sbuf *sb;
141 kstat_t *ksp = arg1;
142 kstat_io_t *kip = ksp->ks_data;
143 int rc;
144
145 sb = sbuf_new_auto();
146 if (sb == NULL)
147 return (ENOMEM);
148 /* Update the aggsums before reading */
149 (void) ksp->ks_update(ksp, KSTAT_READ);
150
151 /* though wlentime & friends are signed, they will never be negative */
152 sbuf_printf(sb,
153 "%-8llu %-8llu %-8u %-8u %-8llu %-8llu "
154 "%-8llu %-8llu %-8llu %-8llu %-8u %-8u\n",
155 kip->nread, kip->nwritten,
156 kip->reads, kip->writes,
157 kip->wtime, kip->wlentime, kip->wlastupdate,
158 kip->rtime, kip->rlentime, kip->rlastupdate,
159 kip->wcnt, kip->rcnt);
160 rc = sbuf_finish(sb);
161 if (rc == 0)
162 rc = SYSCTL_OUT(req, sbuf_data(sb), sbuf_len(sb));
163 sbuf_delete(sb);
164 return (rc);
165 }
166
167 static int
kstat_sysctl_raw(SYSCTL_HANDLER_ARGS)168 kstat_sysctl_raw(SYSCTL_HANDLER_ARGS)
169 {
170 struct sbuf *sb;
171 void *data;
172 kstat_t *ksp = arg1;
173 void *(*addr_op)(kstat_t *ksp, loff_t index);
174 int n, has_header, rc = 0;
175
176 sb = sbuf_new_auto();
177 if (sb == NULL)
178 return (ENOMEM);
179
180 if (ksp->ks_raw_ops.addr)
181 addr_op = ksp->ks_raw_ops.addr;
182 else
183 addr_op = kstat_raw_default_addr;
184
185 mutex_enter(ksp->ks_lock);
186
187 /* Update the aggsums before reading */
188 (void) ksp->ks_update(ksp, KSTAT_READ);
189
190 ksp->ks_raw_bufsize = PAGE_SIZE;
191 ksp->ks_raw_buf = malloc(PAGE_SIZE, M_TEMP, M_WAITOK);
192
193 n = 0;
194 has_header = (ksp->ks_raw_ops.headers ||
195 ksp->ks_raw_ops.seq_headers);
196
197 restart_headers:
198 if (ksp->ks_raw_ops.headers) {
199 rc = ksp->ks_raw_ops.headers(
200 ksp->ks_raw_buf, ksp->ks_raw_bufsize);
201 } else if (ksp->ks_raw_ops.seq_headers) {
202 struct seq_file f;
203
204 f.sf_buf = ksp->ks_raw_buf;
205 f.sf_size = ksp->ks_raw_bufsize;
206 rc = ksp->ks_raw_ops.seq_headers(&f);
207 }
208 if (has_header) {
209 if (rc == ENOMEM && !kstat_resize_raw(ksp))
210 goto restart_headers;
211 if (rc == 0)
212 sbuf_printf(sb, "\n%s", ksp->ks_raw_buf);
213 }
214
215 while ((data = addr_op(ksp, n)) != NULL) {
216 restart:
217 if (ksp->ks_raw_ops.data) {
218 rc = ksp->ks_raw_ops.data(ksp->ks_raw_buf,
219 ksp->ks_raw_bufsize, data);
220 if (rc == ENOMEM && !kstat_resize_raw(ksp))
221 goto restart;
222 if (rc == 0)
223 sbuf_printf(sb, "%s", ksp->ks_raw_buf);
224
225 } else {
226 ASSERT(ksp->ks_ndata == 1);
227 sbuf_hexdump(sb, ksp->ks_data,
228 ksp->ks_data_size, NULL, 0);
229 }
230 n++;
231 }
232 free(ksp->ks_raw_buf, M_TEMP);
233 mutex_exit(ksp->ks_lock);
234 sbuf_trim(sb);
235 rc = sbuf_finish(sb);
236 if (rc == 0)
237 rc = SYSCTL_OUT(req, sbuf_data(sb), sbuf_len(sb));
238 sbuf_delete(sb);
239 return (rc);
240 }
241
242 kstat_t *
__kstat_create(const char * module,int instance,const char * name,const char * class,uchar_t ks_type,uint_t ks_ndata,uchar_t flags)243 __kstat_create(const char *module, int instance, const char *name,
244 const char *class, uchar_t ks_type, uint_t ks_ndata, uchar_t flags)
245 {
246 char buf[KSTAT_STRLEN];
247 struct sysctl_oid *root;
248 kstat_t *ksp;
249 char *pool;
250
251 KASSERT(instance == 0, ("instance=%d", instance));
252 if ((ks_type == KSTAT_TYPE_INTR) || (ks_type == KSTAT_TYPE_IO))
253 ASSERT(ks_ndata == 1);
254
255 if (class == NULL)
256 class = "misc";
257
258 /*
259 * Allocate the main structure. We don't need to keep a copy of
260 * module in here, because it is only used for sysctl node creation
261 * done in this function.
262 */
263 ksp = malloc(sizeof (*ksp), M_KSTAT, M_WAITOK|M_ZERO);
264
265 ksp->ks_crtime = gethrtime();
266 ksp->ks_snaptime = ksp->ks_crtime;
267 ksp->ks_instance = instance;
268 (void) strlcpy(ksp->ks_name, name, KSTAT_STRLEN);
269 (void) strlcpy(ksp->ks_class, class, KSTAT_STRLEN);
270 ksp->ks_type = ks_type;
271 ksp->ks_flags = flags;
272 ksp->ks_update = kstat_default_update;
273
274 mutex_init(&ksp->ks_private_lock, NULL, MUTEX_DEFAULT, NULL);
275 ksp->ks_lock = &ksp->ks_private_lock;
276
277 switch (ksp->ks_type) {
278 case KSTAT_TYPE_RAW:
279 ksp->ks_ndata = 1;
280 ksp->ks_data_size = ks_ndata;
281 break;
282 case KSTAT_TYPE_NAMED:
283 ksp->ks_ndata = ks_ndata;
284 ksp->ks_data_size = ks_ndata * sizeof (kstat_named_t);
285 break;
286 case KSTAT_TYPE_INTR:
287 ksp->ks_ndata = ks_ndata;
288 ksp->ks_data_size = ks_ndata * sizeof (kstat_intr_t);
289 break;
290 case KSTAT_TYPE_IO:
291 ksp->ks_ndata = ks_ndata;
292 ksp->ks_data_size = ks_ndata * sizeof (kstat_io_t);
293 break;
294 case KSTAT_TYPE_TIMER:
295 ksp->ks_ndata = ks_ndata;
296 ksp->ks_data_size = ks_ndata * sizeof (kstat_timer_t);
297 break;
298 default:
299 panic("Undefined kstat type %d\n", ksp->ks_type);
300 }
301
302 if (ksp->ks_flags & KSTAT_FLAG_VIRTUAL) {
303 ksp->ks_data = NULL;
304 } else {
305 ksp->ks_data = kmem_zalloc(ksp->ks_data_size, KM_SLEEP);
306 if (ksp->ks_data == NULL) {
307 kmem_free(ksp, sizeof (*ksp));
308 ksp = NULL;
309 }
310 }
311
312 /*
313 * Some kstats use a module name like "zfs/poolname" to distinguish a
314 * set of kstats belonging to a specific pool. Split on '/' to add an
315 * extra node for the pool name if needed.
316 */
317 (void) strlcpy(buf, module, KSTAT_STRLEN);
318 module = buf;
319 pool = strchr(module, '/');
320 if (pool != NULL)
321 *pool++ = '\0';
322
323 /*
324 * Create sysctl tree for those statistics:
325 *
326 * kstat.<module>[.<pool>].<class>.<name>
327 */
328 sysctl_ctx_init(&ksp->ks_sysctl_ctx);
329 root = SYSCTL_ADD_NODE(&ksp->ks_sysctl_ctx,
330 SYSCTL_STATIC_CHILDREN(_kstat), OID_AUTO, module, CTLFLAG_RW, 0,
331 "");
332 if (root == NULL) {
333 printf("%s: Cannot create kstat.%s tree!\n", __func__, module);
334 sysctl_ctx_free(&ksp->ks_sysctl_ctx);
335 free(ksp, M_KSTAT);
336 return (NULL);
337 }
338 if (pool != NULL) {
339 root = SYSCTL_ADD_NODE(&ksp->ks_sysctl_ctx,
340 SYSCTL_CHILDREN(root), OID_AUTO, pool, CTLFLAG_RW, 0, "");
341 if (root == NULL) {
342 printf("%s: Cannot create kstat.%s.%s tree!\n",
343 __func__, module, pool);
344 sysctl_ctx_free(&ksp->ks_sysctl_ctx);
345 free(ksp, M_KSTAT);
346 return (NULL);
347 }
348 }
349 root = SYSCTL_ADD_NODE(&ksp->ks_sysctl_ctx, SYSCTL_CHILDREN(root),
350 OID_AUTO, class, CTLFLAG_RW, 0, "");
351 if (root == NULL) {
352 if (pool != NULL)
353 printf("%s: Cannot create kstat.%s.%s.%s tree!\n",
354 __func__, module, pool, class);
355 else
356 printf("%s: Cannot create kstat.%s.%s tree!\n",
357 __func__, module, class);
358 sysctl_ctx_free(&ksp->ks_sysctl_ctx);
359 free(ksp, M_KSTAT);
360 return (NULL);
361 }
362 if (ksp->ks_type == KSTAT_TYPE_NAMED) {
363 root = SYSCTL_ADD_NODE(&ksp->ks_sysctl_ctx,
364 SYSCTL_CHILDREN(root),
365 OID_AUTO, name, CTLFLAG_RW, 0, "");
366 if (root == NULL) {
367 if (pool != NULL)
368 printf("%s: Cannot create kstat.%s.%s.%s.%s "
369 "tree!\n", __func__, module, pool, class,
370 name);
371 else
372 printf("%s: Cannot create kstat.%s.%s.%s "
373 "tree!\n", __func__, module, class, name);
374 sysctl_ctx_free(&ksp->ks_sysctl_ctx);
375 free(ksp, M_KSTAT);
376 return (NULL);
377 }
378
379 }
380 ksp->ks_sysctl_root = root;
381
382 return (ksp);
383 }
384
385 static void
kstat_install_named(kstat_t * ksp)386 kstat_install_named(kstat_t *ksp)
387 {
388 kstat_named_t *ksent;
389 char *namelast;
390 int typelast;
391
392 ksent = ksp->ks_data;
393
394 VERIFY((ksp->ks_flags & KSTAT_FLAG_VIRTUAL) || ksent != NULL);
395
396 typelast = 0;
397 namelast = NULL;
398
399 for (int i = 0; i < ksp->ks_ndata; i++, ksent++) {
400 if (ksent->data_type != 0) {
401 typelast = ksent->data_type;
402 namelast = ksent->name;
403 }
404 switch (typelast) {
405 case KSTAT_DATA_CHAR:
406 /* Not Implemented */
407 break;
408 case KSTAT_DATA_INT32:
409 SYSCTL_ADD_PROC(&ksp->ks_sysctl_ctx,
410 SYSCTL_CHILDREN(ksp->ks_sysctl_root),
411 OID_AUTO, namelast,
412 CTLTYPE_S32 | CTLFLAG_RD | CTLFLAG_MPSAFE,
413 ksp, i, kstat_sysctl, "I", namelast);
414 break;
415 case KSTAT_DATA_UINT32:
416 SYSCTL_ADD_PROC(&ksp->ks_sysctl_ctx,
417 SYSCTL_CHILDREN(ksp->ks_sysctl_root),
418 OID_AUTO, namelast,
419 CTLTYPE_U32 | CTLFLAG_RD | CTLFLAG_MPSAFE,
420 ksp, i, kstat_sysctl, "IU", namelast);
421 break;
422 case KSTAT_DATA_INT64:
423 SYSCTL_ADD_PROC(&ksp->ks_sysctl_ctx,
424 SYSCTL_CHILDREN(ksp->ks_sysctl_root),
425 OID_AUTO, namelast,
426 CTLTYPE_S64 | CTLFLAG_RD | CTLFLAG_MPSAFE,
427 ksp, i, kstat_sysctl, "Q", namelast);
428 break;
429 case KSTAT_DATA_UINT64:
430 SYSCTL_ADD_PROC(&ksp->ks_sysctl_ctx,
431 SYSCTL_CHILDREN(ksp->ks_sysctl_root),
432 OID_AUTO, namelast,
433 CTLTYPE_U64 | CTLFLAG_RD | CTLFLAG_MPSAFE,
434 ksp, i, kstat_sysctl, "QU", namelast);
435 break;
436 case KSTAT_DATA_LONG:
437 SYSCTL_ADD_PROC(&ksp->ks_sysctl_ctx,
438 SYSCTL_CHILDREN(ksp->ks_sysctl_root),
439 OID_AUTO, namelast,
440 CTLTYPE_LONG | CTLFLAG_RD | CTLFLAG_MPSAFE,
441 ksp, i, kstat_sysctl, "L", namelast);
442 break;
443 case KSTAT_DATA_ULONG:
444 SYSCTL_ADD_PROC(&ksp->ks_sysctl_ctx,
445 SYSCTL_CHILDREN(ksp->ks_sysctl_root),
446 OID_AUTO, namelast,
447 CTLTYPE_ULONG | CTLFLAG_RD | CTLFLAG_MPSAFE,
448 ksp, i, kstat_sysctl, "LU", namelast);
449 break;
450 case KSTAT_DATA_STRING:
451 SYSCTL_ADD_PROC(&ksp->ks_sysctl_ctx,
452 SYSCTL_CHILDREN(ksp->ks_sysctl_root),
453 OID_AUTO, namelast,
454 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
455 ksp, i, kstat_sysctl_string, "A", namelast);
456 break;
457 default:
458 panic("unsupported type: %d", typelast);
459 }
460 }
461 }
462
463 void
kstat_install(kstat_t * ksp)464 kstat_install(kstat_t *ksp)
465 {
466 struct sysctl_oid *root;
467
468 if (ksp->ks_ndata == UINT32_MAX)
469 VERIFY(ksp->ks_type == KSTAT_TYPE_RAW);
470
471 switch (ksp->ks_type) {
472 case KSTAT_TYPE_NAMED:
473 return (kstat_install_named(ksp));
474 case KSTAT_TYPE_RAW:
475 if (ksp->ks_raw_ops.data) {
476 root = SYSCTL_ADD_PROC(&ksp->ks_sysctl_ctx,
477 SYSCTL_CHILDREN(ksp->ks_sysctl_root),
478 OID_AUTO, ksp->ks_name, CTLTYPE_STRING | CTLFLAG_RD
479 | CTLFLAG_MPSAFE | CTLFLAG_SKIP,
480 ksp, 0, kstat_sysctl_raw, "A", ksp->ks_name);
481 } else {
482 root = SYSCTL_ADD_PROC(&ksp->ks_sysctl_ctx,
483 SYSCTL_CHILDREN(ksp->ks_sysctl_root),
484 OID_AUTO, ksp->ks_name, CTLTYPE_OPAQUE | CTLFLAG_RD
485 | CTLFLAG_MPSAFE | CTLFLAG_SKIP,
486 ksp, 0, kstat_sysctl_raw, "", ksp->ks_name);
487 }
488 break;
489 case KSTAT_TYPE_IO:
490 root = SYSCTL_ADD_PROC(&ksp->ks_sysctl_ctx,
491 SYSCTL_CHILDREN(ksp->ks_sysctl_root),
492 OID_AUTO, ksp->ks_name,
493 CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
494 ksp, 0, kstat_sysctl_io, "A", ksp->ks_name);
495 break;
496 case KSTAT_TYPE_TIMER:
497 case KSTAT_TYPE_INTR:
498 default:
499 panic("unsupported kstat type %d\n", ksp->ks_type);
500 }
501 VERIFY(root != NULL);
502 ksp->ks_sysctl_root = root;
503 }
504
505 void
kstat_delete(kstat_t * ksp)506 kstat_delete(kstat_t *ksp)
507 {
508
509 sysctl_ctx_free(&ksp->ks_sysctl_ctx);
510 ksp->ks_lock = NULL;
511 mutex_destroy(&ksp->ks_private_lock);
512 free(ksp, M_KSTAT);
513 }
514
515 void
kstat_waitq_enter(kstat_io_t * kiop)516 kstat_waitq_enter(kstat_io_t *kiop)
517 {
518 hrtime_t new, delta;
519 ulong_t wcnt;
520
521 new = gethrtime();
522 delta = new - kiop->wlastupdate;
523 kiop->wlastupdate = new;
524 wcnt = kiop->wcnt++;
525 if (wcnt != 0) {
526 kiop->wlentime += delta * wcnt;
527 kiop->wtime += delta;
528 }
529 }
530
531 void
kstat_waitq_exit(kstat_io_t * kiop)532 kstat_waitq_exit(kstat_io_t *kiop)
533 {
534 hrtime_t new, delta;
535 ulong_t wcnt;
536
537 new = gethrtime();
538 delta = new - kiop->wlastupdate;
539 kiop->wlastupdate = new;
540 wcnt = kiop->wcnt--;
541 ASSERT((int)wcnt > 0);
542 kiop->wlentime += delta * wcnt;
543 kiop->wtime += delta;
544 }
545
546 void
kstat_runq_enter(kstat_io_t * kiop)547 kstat_runq_enter(kstat_io_t *kiop)
548 {
549 hrtime_t new, delta;
550 ulong_t rcnt;
551
552 new = gethrtime();
553 delta = new - kiop->rlastupdate;
554 kiop->rlastupdate = new;
555 rcnt = kiop->rcnt++;
556 if (rcnt != 0) {
557 kiop->rlentime += delta * rcnt;
558 kiop->rtime += delta;
559 }
560 }
561
562 void
kstat_runq_exit(kstat_io_t * kiop)563 kstat_runq_exit(kstat_io_t *kiop)
564 {
565 hrtime_t new, delta;
566 ulong_t rcnt;
567
568 new = gethrtime();
569 delta = new - kiop->rlastupdate;
570 kiop->rlastupdate = new;
571 rcnt = kiop->rcnt--;
572 ASSERT((int)rcnt > 0);
573 kiop->rlentime += delta * rcnt;
574 kiop->rtime += delta;
575 }
576