xref: /freebsd/sys/contrib/openzfs/module/os/freebsd/spl/spl_kstat.c (revision 61145dc2b94f12f6a47344fb9aac702321880e43)
1 // SPDX-License-Identifier: BSD-2-Clause
2 /*
3  * Copyright (c) 2007 Pawel Jakub Dawidek <pjd@FreeBSD.org>
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  *
27  * Links to Illumos.org for more information on kstat function:
28  * [1] https://illumos.org/man/1M/kstat
29  * [2] https://illumos.org/man/9f/kstat_create
30  */
31 /*
32  * Copyright (c) 2024-2025, Klara, Inc.
33  * Copyright (c) 2024-2025, Syneto
34  */
35 
36 #include <sys/types.h>
37 #include <sys/param.h>
38 #include <sys/kernel.h>
39 #include <sys/systm.h>
40 #include <sys/malloc.h>
41 #include <sys/sysctl.h>
42 #include <sys/kstat.h>
43 #include <sys/sbuf.h>
44 #include <sys/zone.h>
45 
46 static MALLOC_DEFINE(M_KSTAT, "kstat_data", "Kernel statistics");
47 
48 SYSCTL_ROOT_NODE(OID_AUTO, kstat, CTLFLAG_RW, 0, "Kernel statistics");
49 
50 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))51 __kstat_set_raw_ops(kstat_t *ksp,
52     int (*headers)(char *buf, size_t size),
53     int (*data)(char *buf, size_t size, void *data),
54     void *(*addr)(kstat_t *ksp, loff_t index))
55 {
56 	ksp->ks_raw_ops.headers = headers;
57 	ksp->ks_raw_ops.data    = data;
58 	ksp->ks_raw_ops.addr    = addr;
59 }
60 
61 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))62 __kstat_set_seq_raw_ops(kstat_t *ksp,
63     int (*headers)(struct seq_file *f),
64     int (*data)(char *buf, size_t size, void *data),
65     void *(*addr)(kstat_t *ksp, loff_t index))
66 {
67 	ksp->ks_raw_ops.seq_headers = headers;
68 	ksp->ks_raw_ops.data    = data;
69 	ksp->ks_raw_ops.addr    = addr;
70 }
71 
72 static int
kstat_default_update(kstat_t * ksp,int rw)73 kstat_default_update(kstat_t *ksp, int rw)
74 {
75 	ASSERT3P(ksp, !=, NULL);
76 
77 	if (rw == KSTAT_WRITE)
78 		return (EACCES);
79 
80 	return (0);
81 }
82 
83 static int
kstat_resize_raw(kstat_t * ksp)84 kstat_resize_raw(kstat_t *ksp)
85 {
86 	if (ksp->ks_raw_bufsize == KSTAT_RAW_MAX)
87 		return (ENOMEM);
88 
89 	free(ksp->ks_raw_buf, M_TEMP);
90 	ksp->ks_raw_bufsize = MIN(ksp->ks_raw_bufsize * 2, KSTAT_RAW_MAX);
91 	ksp->ks_raw_buf = malloc(ksp->ks_raw_bufsize, M_TEMP, M_WAITOK);
92 
93 	return (0);
94 }
95 
96 static void *
kstat_raw_default_addr(kstat_t * ksp,loff_t n)97 kstat_raw_default_addr(kstat_t *ksp, loff_t n)
98 {
99 	if (n == 0)
100 		return (ksp->ks_data);
101 	return (NULL);
102 }
103 
104 static int
kstat_sysctl(SYSCTL_HANDLER_ARGS)105 kstat_sysctl(SYSCTL_HANDLER_ARGS)
106 {
107 	kstat_t *ksp = arg1;
108 	kstat_named_t *ksent;
109 	uint64_t val;
110 
111 	ksent = ksp->ks_data;
112 	/* Select the correct element */
113 	ksent += arg2;
114 	/* Update the aggsums before reading */
115 	(void) ksp->ks_update(ksp, KSTAT_READ);
116 	val = ksent->value.ui64;
117 
118 	return (sysctl_handle_64(oidp, &val, 0, req));
119 }
120 
121 static int
kstat_sysctl_string(SYSCTL_HANDLER_ARGS)122 kstat_sysctl_string(SYSCTL_HANDLER_ARGS)
123 {
124 	kstat_t *ksp = arg1;
125 	kstat_named_t *ksent = ksp->ks_data;
126 	char *val;
127 	uint32_t len = 0;
128 
129 	/* Select the correct element */
130 	ksent += arg2;
131 	/* Update the aggsums before reading */
132 	(void) ksp->ks_update(ksp, KSTAT_READ);
133 	val = KSTAT_NAMED_STR_PTR(ksent);
134 	len = KSTAT_NAMED_STR_BUFLEN(ksent);
135 	val[len-1] = '\0';
136 
137 	return (sysctl_handle_string(oidp, val, len, req));
138 }
139 
140 static int
kstat_sysctl_dataset(SYSCTL_HANDLER_ARGS)141 kstat_sysctl_dataset(SYSCTL_HANDLER_ARGS)
142 {
143 	kstat_t *ksp = arg1;
144 	kstat_named_t *ksent;
145 	kstat_named_t *ksent_ds;
146 	uint64_t val;
147 	char *ds_name;
148 	uint32_t ds_len = 0;
149 
150 	ksent_ds = ksent = ksp->ks_data;
151 	ds_name = KSTAT_NAMED_STR_PTR(ksent_ds);
152 	ds_len = KSTAT_NAMED_STR_BUFLEN(ksent_ds);
153 	ds_name[ds_len-1] = '\0';
154 
155 	if (!zone_dataset_visible(ds_name, NULL)) {
156 		return (EPERM);
157 	}
158 
159 	/* Select the correct element */
160 	ksent += arg2;
161 	/* Update the aggsums before reading */
162 	(void) ksp->ks_update(ksp, KSTAT_READ);
163 	val = ksent->value.ui64;
164 
165 	return (sysctl_handle_64(oidp, &val, 0, req));
166 }
167 
168 static int
kstat_sysctl_dataset_string(SYSCTL_HANDLER_ARGS)169 kstat_sysctl_dataset_string(SYSCTL_HANDLER_ARGS)
170 {
171 	kstat_t *ksp = arg1;
172 	kstat_named_t *ksent = ksp->ks_data;
173 	char *val;
174 	uint32_t len = 0;
175 
176 	/* Select the correct element */
177 	ksent += arg2;
178 	val = KSTAT_NAMED_STR_PTR(ksent);
179 	len = KSTAT_NAMED_STR_BUFLEN(ksent);
180 	val[len-1] = '\0';
181 
182 	if (!zone_dataset_visible(val, NULL)) {
183 		return (EPERM);
184 	}
185 
186 	return (sysctl_handle_string(oidp, val, len, req));
187 }
188 
189 static int
kstat_sysctl_io(SYSCTL_HANDLER_ARGS)190 kstat_sysctl_io(SYSCTL_HANDLER_ARGS)
191 {
192 	struct sbuf sb;
193 	kstat_t *ksp = arg1;
194 	kstat_io_t *kip = ksp->ks_data;
195 	int rc;
196 
197 	sbuf_new_for_sysctl(&sb, NULL, 0, req);
198 
199 	/* Update the aggsums before reading */
200 	(void) ksp->ks_update(ksp, KSTAT_READ);
201 
202 	/* though wlentime & friends are signed, they will never be negative */
203 	sbuf_printf(&sb,
204 	    "%-8llu %-8llu %-8u %-8u %-8llu %-8llu "
205 	    "%-8llu %-8llu %-8llu %-8llu %-8u %-8u\n",
206 	    kip->nread, kip->nwritten,
207 	    kip->reads, kip->writes,
208 	    kip->wtime, kip->wlentime, kip->wlastupdate,
209 	    kip->rtime, kip->rlentime, kip->rlastupdate,
210 	    kip->wcnt,  kip->rcnt);
211 	rc = sbuf_finish(&sb);
212 	sbuf_delete(&sb);
213 	return (rc);
214 }
215 
216 static int
kstat_sysctl_raw(SYSCTL_HANDLER_ARGS)217 kstat_sysctl_raw(SYSCTL_HANDLER_ARGS)
218 {
219 	struct sbuf sb;
220 	void *data;
221 	kstat_t *ksp = arg1;
222 	void *(*addr_op)(kstat_t *ksp, loff_t index);
223 	int n, has_header, rc = 0;
224 
225 	sbuf_new_for_sysctl(&sb, NULL, PAGE_SIZE, req);
226 
227 	if (ksp->ks_raw_ops.addr)
228 		addr_op = ksp->ks_raw_ops.addr;
229 	else
230 		addr_op = kstat_raw_default_addr;
231 
232 	mutex_enter(ksp->ks_lock);
233 
234 	/* Update the aggsums before reading */
235 	(void) ksp->ks_update(ksp, KSTAT_READ);
236 
237 	ksp->ks_raw_bufsize = PAGE_SIZE;
238 	ksp->ks_raw_buf = malloc(PAGE_SIZE, M_TEMP, M_WAITOK);
239 
240 	n = 0;
241 	has_header = (ksp->ks_raw_ops.headers ||
242 	    ksp->ks_raw_ops.seq_headers);
243 
244 restart_headers:
245 	if (ksp->ks_raw_ops.headers) {
246 		rc = ksp->ks_raw_ops.headers(
247 		    ksp->ks_raw_buf, ksp->ks_raw_bufsize);
248 	} else if (ksp->ks_raw_ops.seq_headers) {
249 		struct seq_file f;
250 
251 		f.sf_buf = ksp->ks_raw_buf;
252 		f.sf_size = ksp->ks_raw_bufsize;
253 		rc = ksp->ks_raw_ops.seq_headers(&f);
254 	}
255 	if (has_header) {
256 		if (rc == ENOMEM && !kstat_resize_raw(ksp))
257 			goto restart_headers;
258 		if (rc == 0) {
259 			sbuf_cat(&sb, "\n");
260 			sbuf_cat(&sb, ksp->ks_raw_buf);
261 		}
262 	}
263 
264 	while ((data = addr_op(ksp, n)) != NULL) {
265 restart:
266 		if (ksp->ks_raw_ops.data) {
267 			rc = ksp->ks_raw_ops.data(ksp->ks_raw_buf,
268 			    ksp->ks_raw_bufsize, data);
269 			if (rc == ENOMEM && !kstat_resize_raw(ksp))
270 				goto restart;
271 			if (rc == 0)
272 				sbuf_cat(&sb, ksp->ks_raw_buf);
273 
274 		} else {
275 			ASSERT3U(ksp->ks_ndata, ==, 1);
276 			sbuf_hexdump(&sb, ksp->ks_data,
277 			    ksp->ks_data_size, NULL, 0);
278 		}
279 		n++;
280 	}
281 	free(ksp->ks_raw_buf, M_TEMP);
282 	mutex_exit(ksp->ks_lock);
283 	rc = sbuf_finish(&sb);
284 	sbuf_delete(&sb);
285 	return (rc);
286 }
287 
288 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)289 __kstat_create(const char *module, int instance, const char *name,
290     const char *class, uchar_t ks_type, uint_t ks_ndata, uchar_t flags)
291 {
292 	char buf[KSTAT_STRLEN];
293 	struct sysctl_oid *root;
294 	kstat_t *ksp;
295 	char *p, *frag;
296 
297 	KASSERT(instance == 0, ("instance=%d", instance));
298 	if ((ks_type == KSTAT_TYPE_INTR) || (ks_type == KSTAT_TYPE_IO))
299 		ASSERT3U(ks_ndata, ==, 1);
300 
301 	if (class == NULL)
302 		class = "misc";
303 
304 	/*
305 	 * Allocate the main structure. We don't need to keep a copy of
306 	 * module in here, because it is only used for sysctl node creation
307 	 * done in this function.
308 	 */
309 	ksp = malloc(sizeof (*ksp), M_KSTAT, M_WAITOK|M_ZERO);
310 
311 	ksp->ks_crtime = gethrtime();
312 	ksp->ks_snaptime = ksp->ks_crtime;
313 	ksp->ks_instance = instance;
314 	(void) strlcpy(ksp->ks_name, name, KSTAT_STRLEN);
315 	(void) strlcpy(ksp->ks_class, class, KSTAT_STRLEN);
316 	ksp->ks_type = ks_type;
317 	ksp->ks_flags = flags;
318 	ksp->ks_update = kstat_default_update;
319 
320 	mutex_init(&ksp->ks_private_lock, NULL, MUTEX_DEFAULT, NULL);
321 	ksp->ks_lock = &ksp->ks_private_lock;
322 
323 	switch (ksp->ks_type) {
324 	case KSTAT_TYPE_RAW:
325 		ksp->ks_ndata = 1;
326 		ksp->ks_data_size = ks_ndata;
327 		break;
328 	case KSTAT_TYPE_NAMED:
329 		ksp->ks_ndata = ks_ndata;
330 		ksp->ks_data_size = ks_ndata * sizeof (kstat_named_t);
331 		break;
332 	case KSTAT_TYPE_INTR:
333 		ksp->ks_ndata = ks_ndata;
334 		ksp->ks_data_size = ks_ndata * sizeof (kstat_intr_t);
335 		break;
336 	case KSTAT_TYPE_IO:
337 		ksp->ks_ndata = ks_ndata;
338 		ksp->ks_data_size = ks_ndata * sizeof (kstat_io_t);
339 		break;
340 	case KSTAT_TYPE_TIMER:
341 		ksp->ks_ndata = ks_ndata;
342 		ksp->ks_data_size = ks_ndata * sizeof (kstat_timer_t);
343 		break;
344 	default:
345 		panic("Undefined kstat type %d\n", ksp->ks_type);
346 	}
347 
348 	if (ksp->ks_flags & KSTAT_FLAG_VIRTUAL)
349 		ksp->ks_data = NULL;
350 	else
351 		ksp->ks_data = kmem_zalloc(ksp->ks_data_size, KM_SLEEP);
352 
353 	sysctl_ctx_init(&ksp->ks_sysctl_ctx);
354 
355 	(void) strlcpy(buf, module, KSTAT_STRLEN);
356 
357 	/*
358 	 * Walk over the module name, splitting on '/', and create the
359 	 * intermediate nodes.
360 	 */
361 	root = NULL;
362 	p = buf;
363 	while ((frag = strsep(&p, "/")) != NULL) {
364 		root = SYSCTL_ADD_NODE(&ksp->ks_sysctl_ctx, root ?
365 		    SYSCTL_CHILDREN(root) : SYSCTL_STATIC_CHILDREN(_kstat),
366 		    OID_AUTO, frag, CTLFLAG_RW, 0, "");
367 		if (root == NULL) {
368 			printf("%s: Cannot create kstat.%s tree!\n",
369 			    __func__, buf);
370 			sysctl_ctx_free(&ksp->ks_sysctl_ctx);
371 			free(ksp, M_KSTAT);
372 			return (NULL);
373 		}
374 		if (p != NULL)
375 			p[-1] = '.';
376 	}
377 
378 	root = SYSCTL_ADD_NODE(&ksp->ks_sysctl_ctx, SYSCTL_CHILDREN(root),
379 	    OID_AUTO, class, CTLFLAG_RW, 0, "");
380 	if (root == NULL) {
381 		printf("%s: Cannot create kstat.%s.%s tree!\n",
382 		    __func__, buf, class);
383 		sysctl_ctx_free(&ksp->ks_sysctl_ctx);
384 		free(ksp, M_KSTAT);
385 		return (NULL);
386 	}
387 
388 	if (ksp->ks_type == KSTAT_TYPE_NAMED) {
389 		root = SYSCTL_ADD_NODE(&ksp->ks_sysctl_ctx,
390 		    SYSCTL_CHILDREN(root),
391 		    OID_AUTO, name, CTLFLAG_RW, 0, "");
392 		if (root == NULL) {
393 			printf("%s: Cannot create kstat.%s.%s.%s tree!\n",
394 			    __func__, buf, class, name);
395 			sysctl_ctx_free(&ksp->ks_sysctl_ctx);
396 			free(ksp, M_KSTAT);
397 			return (NULL);
398 		}
399 	}
400 
401 	ksp->ks_sysctl_root = root;
402 
403 	return (ksp);
404 }
405 
406 static void
kstat_install_named(kstat_t * ksp)407 kstat_install_named(kstat_t *ksp)
408 {
409 	kstat_named_t *ksent;
410 	char *namelast;
411 	int typelast;
412 
413 	ksent = ksp->ks_data;
414 
415 	VERIFY((ksp->ks_flags & KSTAT_FLAG_VIRTUAL) || ksent != NULL);
416 
417 	typelast = 0;
418 	namelast = NULL;
419 
420 	for (int i = 0; i < ksp->ks_ndata; i++, ksent++) {
421 		if (ksent->data_type != 0) {
422 			typelast = ksent->data_type;
423 			namelast = ksent->name;
424 
425 			/*
426 			 * If a sysctl with this name already exists on this on
427 			 * this root, first remove it by deleting it from its
428 			 * old context, and then destroying it.
429 			 */
430 			struct sysctl_oid *oid = NULL;
431 			SYSCTL_FOREACH(oid,
432 			    SYSCTL_CHILDREN(ksp->ks_sysctl_root)) {
433 				if (strcmp(oid->oid_name, namelast) == 0) {
434 					kstat_t *oldksp =
435 					    (kstat_t *)oid->oid_arg1;
436 					sysctl_ctx_entry_del(
437 					    &oldksp->ks_sysctl_ctx, oid);
438 					sysctl_remove_oid(oid, 1, 0);
439 					break;
440 				}
441 			}
442 		}
443 
444 		switch (typelast) {
445 		case KSTAT_DATA_CHAR:
446 			/* Not Implemented */
447 			break;
448 		case KSTAT_DATA_INT32:
449 			SYSCTL_ADD_PROC(&ksp->ks_sysctl_ctx,
450 			    SYSCTL_CHILDREN(ksp->ks_sysctl_root),
451 			    OID_AUTO, namelast,
452 			    CTLTYPE_S32 | CTLFLAG_RD | CTLFLAG_MPSAFE,
453 			    ksp, i, kstat_sysctl, "I", namelast);
454 			break;
455 		case KSTAT_DATA_UINT32:
456 			SYSCTL_ADD_PROC(&ksp->ks_sysctl_ctx,
457 			    SYSCTL_CHILDREN(ksp->ks_sysctl_root),
458 			    OID_AUTO, namelast,
459 			    CTLTYPE_U32 | CTLFLAG_RD | CTLFLAG_MPSAFE,
460 			    ksp, i, kstat_sysctl, "IU", namelast);
461 			break;
462 		case KSTAT_DATA_INT64:
463 			SYSCTL_ADD_PROC(&ksp->ks_sysctl_ctx,
464 			    SYSCTL_CHILDREN(ksp->ks_sysctl_root),
465 			    OID_AUTO, namelast,
466 			    CTLTYPE_S64 | CTLFLAG_RD | CTLFLAG_MPSAFE,
467 			    ksp, i, kstat_sysctl, "Q", namelast);
468 			break;
469 		case KSTAT_DATA_UINT64:
470 			if (strcmp(ksp->ks_class, "dataset") == 0) {
471 				SYSCTL_ADD_PROC(&ksp->ks_sysctl_ctx,
472 				    SYSCTL_CHILDREN(ksp->ks_sysctl_root),
473 				    OID_AUTO, namelast,
474 				    CTLTYPE_U64 | CTLFLAG_RD | CTLFLAG_MPSAFE,
475 				    ksp, i, kstat_sysctl_dataset, "QU",
476 				    namelast);
477 			} else {
478 				SYSCTL_ADD_PROC(&ksp->ks_sysctl_ctx,
479 				    SYSCTL_CHILDREN(ksp->ks_sysctl_root),
480 				    OID_AUTO, namelast,
481 				    CTLTYPE_U64 | CTLFLAG_RD | CTLFLAG_MPSAFE,
482 				    ksp, i, kstat_sysctl, "QU", namelast);
483 			}
484 			break;
485 		case KSTAT_DATA_LONG:
486 			SYSCTL_ADD_PROC(&ksp->ks_sysctl_ctx,
487 			    SYSCTL_CHILDREN(ksp->ks_sysctl_root),
488 			    OID_AUTO, namelast,
489 			    CTLTYPE_LONG | CTLFLAG_RD | CTLFLAG_MPSAFE,
490 			    ksp, i, kstat_sysctl, "L", namelast);
491 			break;
492 		case KSTAT_DATA_ULONG:
493 			SYSCTL_ADD_PROC(&ksp->ks_sysctl_ctx,
494 			    SYSCTL_CHILDREN(ksp->ks_sysctl_root),
495 			    OID_AUTO, namelast,
496 			    CTLTYPE_ULONG | CTLFLAG_RD | CTLFLAG_MPSAFE,
497 			    ksp, i, kstat_sysctl, "LU", namelast);
498 			break;
499 		case KSTAT_DATA_STRING:
500 			if (strcmp(ksp->ks_class, "dataset") == 0) {
501 				SYSCTL_ADD_PROC(&ksp->ks_sysctl_ctx,
502 				    SYSCTL_CHILDREN(ksp->ks_sysctl_root),
503 				    OID_AUTO, namelast, CTLTYPE_STRING |
504 				    CTLFLAG_RD | CTLFLAG_MPSAFE,
505 				    ksp, i, kstat_sysctl_dataset_string, "A",
506 				    namelast);
507 			} else {
508 				SYSCTL_ADD_PROC(&ksp->ks_sysctl_ctx,
509 				    SYSCTL_CHILDREN(ksp->ks_sysctl_root),
510 				    OID_AUTO, namelast, CTLTYPE_STRING |
511 				    CTLFLAG_RD | CTLFLAG_MPSAFE,
512 				    ksp, i, kstat_sysctl_string, "A",
513 				    namelast);
514 			}
515 			break;
516 		default:
517 			panic("unsupported type: %d", typelast);
518 		}
519 	}
520 }
521 
522 void
kstat_install(kstat_t * ksp)523 kstat_install(kstat_t *ksp)
524 {
525 	struct sysctl_oid *root;
526 
527 	if (ksp->ks_ndata == UINT32_MAX)
528 		VERIFY3U(ksp->ks_type, ==, KSTAT_TYPE_RAW);
529 
530 	switch (ksp->ks_type) {
531 	case KSTAT_TYPE_NAMED:
532 		return (kstat_install_named(ksp));
533 	case KSTAT_TYPE_RAW:
534 		if (ksp->ks_raw_ops.data) {
535 			root = SYSCTL_ADD_PROC(&ksp->ks_sysctl_ctx,
536 			    SYSCTL_CHILDREN(ksp->ks_sysctl_root),
537 			    OID_AUTO, ksp->ks_name, CTLTYPE_STRING | CTLFLAG_RD
538 			    | CTLFLAG_MPSAFE | CTLFLAG_SKIP,
539 			    ksp, 0, kstat_sysctl_raw, "A", ksp->ks_name);
540 		} else {
541 			root = SYSCTL_ADD_PROC(&ksp->ks_sysctl_ctx,
542 			    SYSCTL_CHILDREN(ksp->ks_sysctl_root),
543 			    OID_AUTO, ksp->ks_name, CTLTYPE_OPAQUE | CTLFLAG_RD
544 			    | CTLFLAG_MPSAFE | CTLFLAG_SKIP,
545 			    ksp, 0, kstat_sysctl_raw, "", ksp->ks_name);
546 		}
547 		break;
548 	case KSTAT_TYPE_IO:
549 		root = SYSCTL_ADD_PROC(&ksp->ks_sysctl_ctx,
550 		    SYSCTL_CHILDREN(ksp->ks_sysctl_root),
551 		    OID_AUTO, ksp->ks_name,
552 		    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_MPSAFE,
553 		    ksp, 0, kstat_sysctl_io, "A", ksp->ks_name);
554 		break;
555 	case KSTAT_TYPE_TIMER:
556 	case KSTAT_TYPE_INTR:
557 	default:
558 		panic("unsupported kstat type %d\n", ksp->ks_type);
559 	}
560 	VERIFY3P(root, !=, NULL);
561 	ksp->ks_sysctl_root = root;
562 }
563 
564 void
kstat_delete(kstat_t * ksp)565 kstat_delete(kstat_t *ksp)
566 {
567 
568 	sysctl_ctx_free(&ksp->ks_sysctl_ctx);
569 	ksp->ks_lock = NULL;
570 	mutex_destroy(&ksp->ks_private_lock);
571 	if (!(ksp->ks_flags & KSTAT_FLAG_VIRTUAL))
572 		kmem_free(ksp->ks_data, ksp->ks_data_size);
573 	free(ksp, M_KSTAT);
574 }
575