1 /*-
2  * Copyright (c) 1982, 1986, 1989, 1993
3  *	The Regents of the University of California.  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  * 4. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 THE REGENTS 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  *	@(#)vm_meter.c	8.4 (Berkeley) 1/4/94
30  */
31 
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD: stable/9/sys/vm/vm_meter.c 284100 2015-06-06 20:37:40Z jhb $");
34 
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 #include <sys/kernel.h>
38 #include <sys/lock.h>
39 #include <sys/mutex.h>
40 #include <sys/proc.h>
41 #include <sys/resource.h>
42 #include <sys/sx.h>
43 #include <sys/vmmeter.h>
44 #include <sys/smp.h>
45 
46 #include <vm/vm.h>
47 #include <vm/vm_page.h>
48 #include <vm/vm_extern.h>
49 #include <vm/vm_param.h>
50 #include <vm/pmap.h>
51 #include <vm/vm_map.h>
52 #include <vm/vm_object.h>
53 #include <sys/sysctl.h>
54 
55 struct vmmeter cnt;
56 
57 SYSCTL_UINT(_vm, VM_V_FREE_MIN, v_free_min,
58 	CTLFLAG_RW, &cnt.v_free_min, 0, "");
59 SYSCTL_UINT(_vm, VM_V_FREE_TARGET, v_free_target,
60 	CTLFLAG_RW, &cnt.v_free_target, 0, "");
61 SYSCTL_UINT(_vm, VM_V_FREE_RESERVED, v_free_reserved,
62 	CTLFLAG_RW, &cnt.v_free_reserved, 0, "");
63 SYSCTL_UINT(_vm, VM_V_INACTIVE_TARGET, v_inactive_target,
64 	CTLFLAG_RW, &cnt.v_inactive_target, 0, "");
65 SYSCTL_UINT(_vm, VM_V_CACHE_MIN, v_cache_min,
66 	CTLFLAG_RW, &cnt.v_cache_min, 0, "");
67 SYSCTL_UINT(_vm, VM_V_CACHE_MAX, v_cache_max,
68 	CTLFLAG_RW, &cnt.v_cache_max, 0, "");
69 SYSCTL_UINT(_vm, VM_V_PAGEOUT_FREE_MIN, v_pageout_free_min,
70 	CTLFLAG_RW, &cnt.v_pageout_free_min, 0, "");
71 SYSCTL_UINT(_vm, OID_AUTO, v_free_severe,
72 	CTLFLAG_RW, &cnt.v_free_severe, 0, "");
73 
74 static int
sysctl_vm_loadavg(SYSCTL_HANDLER_ARGS)75 sysctl_vm_loadavg(SYSCTL_HANDLER_ARGS)
76 {
77 
78 #ifdef SCTL_MASK32
79 	u_int32_t la[4];
80 
81 	if (req->flags & SCTL_MASK32) {
82 		la[0] = averunnable.ldavg[0];
83 		la[1] = averunnable.ldavg[1];
84 		la[2] = averunnable.ldavg[2];
85 		la[3] = averunnable.fscale;
86 		return SYSCTL_OUT(req, la, sizeof(la));
87 	} else
88 #endif
89 		return SYSCTL_OUT(req, &averunnable, sizeof(averunnable));
90 }
91 SYSCTL_PROC(_vm, VM_LOADAVG, loadavg, CTLTYPE_STRUCT | CTLFLAG_RD |
92     CTLFLAG_MPSAFE, NULL, 0, sysctl_vm_loadavg, "S,loadavg",
93     "Machine loadaverage history");
94 
95 static int
vmtotal(SYSCTL_HANDLER_ARGS)96 vmtotal(SYSCTL_HANDLER_ARGS)
97 {
98 	struct proc *p;
99 	struct vmtotal total;
100 	vm_map_entry_t entry;
101 	vm_object_t object;
102 	vm_map_t map;
103 	int paging;
104 	struct thread *td;
105 	struct vmspace *vm;
106 
107 	bzero(&total, sizeof(total));
108 	/*
109 	 * Mark all objects as inactive.
110 	 */
111 	mtx_lock(&vm_object_list_mtx);
112 	TAILQ_FOREACH(object, &vm_object_list, object_list) {
113 		VM_OBJECT_LOCK(object);
114 		vm_object_clear_flag(object, OBJ_ACTIVE);
115 		VM_OBJECT_UNLOCK(object);
116 	}
117 	mtx_unlock(&vm_object_list_mtx);
118 	/*
119 	 * Calculate process statistics.
120 	 */
121 	sx_slock(&allproc_lock);
122 	FOREACH_PROC_IN_SYSTEM(p) {
123 		if (p->p_flag & P_SYSTEM)
124 			continue;
125 		PROC_LOCK(p);
126 		switch (p->p_state) {
127 		case PRS_NEW:
128 			PROC_UNLOCK(p);
129 			continue;
130 			break;
131 		default:
132 			FOREACH_THREAD_IN_PROC(p, td) {
133 				thread_lock(td);
134 				switch (td->td_state) {
135 				case TDS_INHIBITED:
136 					if (TD_IS_SWAPPED(td))
137 						total.t_sw++;
138 					else if (TD_IS_SLEEPING(td) &&
139 					    td->td_priority <= PZERO)
140 						total.t_dw++;
141 					else
142 						total.t_sl++;
143 					break;
144 
145 				case TDS_CAN_RUN:
146 					total.t_sw++;
147 					break;
148 				case TDS_RUNQ:
149 				case TDS_RUNNING:
150 					total.t_rq++;
151 					thread_unlock(td);
152 					continue;
153 				default:
154 					break;
155 				}
156 				thread_unlock(td);
157 			}
158 		}
159 		PROC_UNLOCK(p);
160 		/*
161 		 * Note active objects.
162 		 */
163 		paging = 0;
164 		vm = vmspace_acquire_ref(p);
165 		if (vm == NULL)
166 			continue;
167 		map = &vm->vm_map;
168 		vm_map_lock_read(map);
169 		for (entry = map->header.next;
170 		    entry != &map->header; entry = entry->next) {
171 			if ((entry->eflags & MAP_ENTRY_IS_SUB_MAP) ||
172 			    (object = entry->object.vm_object) == NULL)
173 				continue;
174 			VM_OBJECT_LOCK(object);
175 			vm_object_set_flag(object, OBJ_ACTIVE);
176 			paging |= object->paging_in_progress;
177 			VM_OBJECT_UNLOCK(object);
178 		}
179 		vm_map_unlock_read(map);
180 		vmspace_free(vm);
181 		if (paging)
182 			total.t_pw++;
183 	}
184 	sx_sunlock(&allproc_lock);
185 	/*
186 	 * Calculate object memory usage statistics.
187 	 */
188 	mtx_lock(&vm_object_list_mtx);
189 	TAILQ_FOREACH(object, &vm_object_list, object_list) {
190 		/*
191 		 * Perform unsynchronized reads on the object.  In
192 		 * this case, the lack of synchronization should not
193 		 * impair the accuracy of the reported statistics.
194 		 */
195 		if (object->type == OBJT_DEVICE || object->type == OBJT_SG) {
196 			/*
197 			 * Devices, like /dev/mem, will badly skew our totals.
198 			 */
199 			continue;
200 		}
201 		if (object->ref_count == 0) {
202 			/*
203 			 * Also skip unreferenced objects, including
204 			 * vnodes representing mounted file systems.
205 			 */
206 			continue;
207 		}
208 		total.t_vm += object->size;
209 		total.t_rm += object->resident_page_count;
210 		if (object->flags & OBJ_ACTIVE) {
211 			total.t_avm += object->size;
212 			total.t_arm += object->resident_page_count;
213 		}
214 		if (object->shadow_count > 1) {
215 			/* shared object */
216 			total.t_vmshr += object->size;
217 			total.t_rmshr += object->resident_page_count;
218 			if (object->flags & OBJ_ACTIVE) {
219 				total.t_avmshr += object->size;
220 				total.t_armshr += object->resident_page_count;
221 			}
222 		}
223 	}
224 	mtx_unlock(&vm_object_list_mtx);
225 	total.t_free = cnt.v_free_count + cnt.v_cache_count;
226 	return (sysctl_handle_opaque(oidp, &total, sizeof(total), req));
227 }
228 
229 /*
230  * vcnt() -	accumulate statistics from all cpus and the global cnt
231  *		structure.
232  *
233  *	The vmmeter structure is now per-cpu as well as global.  Those
234  *	statistics which can be kept on a per-cpu basis (to avoid cache
235  *	stalls between cpus) can be moved to the per-cpu vmmeter.  Remaining
236  *	statistics, such as v_free_reserved, are left in the global
237  *	structure.
238  *
239  * (sysctl_oid *oidp, void *arg1, int arg2, struct sysctl_req *req)
240  */
241 static int
vcnt(SYSCTL_HANDLER_ARGS)242 vcnt(SYSCTL_HANDLER_ARGS)
243 {
244 	int count = *(int *)arg1;
245 	int offset = (char *)arg1 - (char *)&cnt;
246 	int i;
247 
248 	CPU_FOREACH(i) {
249 		struct pcpu *pcpu = pcpu_find(i);
250 		count += *(int *)((char *)&pcpu->pc_cnt + offset);
251 	}
252 	return (SYSCTL_OUT(req, &count, sizeof(int)));
253 }
254 
255 SYSCTL_PROC(_vm, VM_TOTAL, vmtotal, CTLTYPE_OPAQUE|CTLFLAG_RD|CTLFLAG_MPSAFE,
256     0, sizeof(struct vmtotal), vmtotal, "S,vmtotal",
257     "System virtual memory statistics");
258 SYSCTL_NODE(_vm, OID_AUTO, stats, CTLFLAG_RW, 0, "VM meter stats");
259 static SYSCTL_NODE(_vm_stats, OID_AUTO, sys, CTLFLAG_RW, 0,
260 	"VM meter sys stats");
261 static SYSCTL_NODE(_vm_stats, OID_AUTO, vm, CTLFLAG_RW, 0,
262 	"VM meter vm stats");
263 SYSCTL_NODE(_vm_stats, OID_AUTO, misc, CTLFLAG_RW, 0, "VM meter misc stats");
264 
265 SYSCTL_PROC(_vm_stats_sys, OID_AUTO, v_swtch, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
266 	&cnt.v_swtch, 0, vcnt, "IU", "Context switches");
267 SYSCTL_PROC(_vm_stats_sys, OID_AUTO, v_trap, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
268 	&cnt.v_trap, 0, vcnt, "IU", "Traps");
269 SYSCTL_PROC(_vm_stats_sys, OID_AUTO, v_syscall, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
270 	&cnt.v_syscall, 0, vcnt, "IU", "Syscalls");
271 SYSCTL_PROC(_vm_stats_sys, OID_AUTO, v_intr, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
272 	&cnt.v_intr, 0, vcnt, "IU", "Hardware interrupts");
273 SYSCTL_PROC(_vm_stats_sys, OID_AUTO, v_soft, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
274 	&cnt.v_soft, 0, vcnt, "IU", "Software interrupts");
275 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_vm_faults, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
276 	&cnt.v_vm_faults, 0, vcnt, "IU", "VM faults");
277 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_cow_faults, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
278 	&cnt.v_cow_faults, 0, vcnt, "IU", "COW faults");
279 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_cow_optim, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
280 	&cnt.v_cow_optim, 0, vcnt, "IU", "Optimized COW faults");
281 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_zfod, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
282 	&cnt.v_zfod, 0, vcnt, "IU", "Zero fill");
283 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_ozfod, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
284 	&cnt.v_ozfod, 0, vcnt, "IU", "Optimized zero fill");
285 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_swapin, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
286 	&cnt.v_swapin, 0, vcnt, "IU", "Swapin operations");
287 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_swapout, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
288 	&cnt.v_swapout, 0, vcnt, "IU", "Swapout operations");
289 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_swappgsin, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
290 	&cnt.v_swappgsin, 0, vcnt, "IU", "Swapin pages");
291 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_swappgsout, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
292 	&cnt.v_swappgsout, 0, vcnt, "IU", "Swapout pages");
293 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_vnodein, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
294 	&cnt.v_vnodein, 0, vcnt, "IU", "Vnodein operations");
295 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_vnodeout, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
296 	&cnt.v_vnodeout, 0, vcnt, "IU", "Vnodeout operations");
297 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_vnodepgsin, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
298 	&cnt.v_vnodepgsin, 0, vcnt, "IU", "Vnodein pages");
299 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_vnodepgsout, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
300 	&cnt.v_vnodepgsout, 0, vcnt, "IU", "Vnodeout pages");
301 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_intrans, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
302 	&cnt.v_intrans, 0, vcnt, "IU", "In transit page blocking");
303 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_reactivated, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
304 	&cnt.v_reactivated, 0, vcnt, "IU", "Reactivated pages");
305 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_pdwakeups, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
306 	&cnt.v_pdwakeups, 0, vcnt, "IU", "Pagedaemon wakeups");
307 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_pdpages, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
308 	&cnt.v_pdpages, 0, vcnt, "IU", "Pagedaemon page scans");
309 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_tcached, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
310 	&cnt.v_tcached, 0, vcnt, "IU", "Total pages cached");
311 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_dfree, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
312 	&cnt.v_dfree, 0, vcnt, "IU", "");
313 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_pfree, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
314 	&cnt.v_pfree, 0, vcnt, "IU", "");
315 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_tfree, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
316 	&cnt.v_tfree, 0, vcnt, "IU", "");
317 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_page_size, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
318 	&cnt.v_page_size, 0, vcnt, "IU", "");
319 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_page_count, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
320 	&cnt.v_page_count, 0, vcnt, "IU", "");
321 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_free_reserved, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
322 	&cnt.v_free_reserved, 0, vcnt, "IU", "");
323 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_free_target, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
324 	&cnt.v_free_target, 0, vcnt, "IU", "");
325 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_free_min, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
326 	&cnt.v_free_min, 0, vcnt, "IU", "");
327 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_free_count, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
328 	&cnt.v_free_count, 0, vcnt, "IU", "");
329 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_wire_count, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
330 	&cnt.v_wire_count, 0, vcnt, "IU", "");
331 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_active_count, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
332 	&cnt.v_active_count, 0, vcnt, "IU", "");
333 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_inactive_target, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
334 	&cnt.v_inactive_target, 0, vcnt, "IU", "");
335 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_inactive_count, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
336 	&cnt.v_inactive_count, 0, vcnt, "IU", "");
337 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_cache_count, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
338 	&cnt.v_cache_count, 0, vcnt, "IU", "");
339 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_cache_min, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
340 	&cnt.v_cache_min, 0, vcnt, "IU", "");
341 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_cache_max, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
342 	&cnt.v_cache_max, 0, vcnt, "IU", "");
343 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_pageout_free_min, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
344 	&cnt.v_pageout_free_min, 0, vcnt, "IU", "");
345 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_interrupt_free_min, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
346 	&cnt.v_interrupt_free_min, 0, vcnt, "IU", "");
347 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_forks, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
348 	&cnt.v_forks, 0, vcnt, "IU", "Number of fork() calls");
349 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_vforks, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
350 	&cnt.v_vforks, 0, vcnt, "IU", "Number of vfork() calls");
351 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_rforks, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
352 	&cnt.v_rforks, 0, vcnt, "IU", "Number of rfork() calls");
353 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_kthreads, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
354 	&cnt.v_kthreads, 0, vcnt, "IU", "Number of fork() calls by kernel");
355 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_forkpages, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
356 	&cnt.v_forkpages, 0, vcnt, "IU", "VM pages affected by fork()");
357 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_vforkpages, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
358 	&cnt.v_vforkpages, 0, vcnt, "IU", "VM pages affected by vfork()");
359 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_rforkpages, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
360 	&cnt.v_rforkpages, 0, vcnt, "IU", "VM pages affected by rfork()");
361 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_kthreadpages, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
362 	&cnt.v_kthreadpages, 0, vcnt, "IU", "VM pages affected by fork() by kernel");
363 
364 SYSCTL_INT(_vm_stats_misc, OID_AUTO,
365 	zero_page_count, CTLFLAG_RD, &vm_page_zero_count, 0, "");
366