sys/vm/vm_meter.c

   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("$FreeBSD$");
  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 int maxslp = MAXSLP;
  58
  59 SYSCTL_UINT(_vm, VM_V_FREE_MIN, v_free_min,
  60         CTLFLAG_RW, &cnt.v_free_min, 0, "");
  61 SYSCTL_UINT(_vm, VM_V_FREE_TARGET, v_free_target,
  62         CTLFLAG_RW, &cnt.v_free_target, 0, "");
  63 SYSCTL_UINT(_vm, VM_V_FREE_RESERVED, v_free_reserved,
  64         CTLFLAG_RW, &cnt.v_free_reserved, 0, "");
  65 SYSCTL_UINT(_vm, VM_V_INACTIVE_TARGET, v_inactive_target,
  66         CTLFLAG_RW, &cnt.v_inactive_target, 0, "");
  67 SYSCTL_UINT(_vm, VM_V_CACHE_MIN, v_cache_min,
  68         CTLFLAG_RW, &cnt.v_cache_min, 0, "");
  69 SYSCTL_UINT(_vm, VM_V_CACHE_MAX, v_cache_max,
  70         CTLFLAG_RW, &cnt.v_cache_max, 0, "");
  71 SYSCTL_UINT(_vm, VM_V_PAGEOUT_FREE_MIN, v_pageout_free_min,
  72         CTLFLAG_RW, &cnt.v_pageout_free_min, 0, "");
  73 SYSCTL_UINT(_vm, OID_AUTO, v_free_severe,
  74         CTLFLAG_RW, &cnt.v_free_severe, 0, "");
  75
  76 static int
  77 sysctl_vm_loadavg(SYSCTL_HANDLER_ARGS)
  78 {
  79
  80 #ifdef SCTL_MASK32
  81         u_int32_t la[4];
  82
  83         if (req->flags & SCTL_MASK32) {
  84                 la[0] = averunnable.ldavg[0];
  85                 la[1] = averunnable.ldavg[1];
  86                 la[2] = averunnable.ldavg[2];
  87                 la[3] = averunnable.fscale;
  88                 return SYSCTL_OUT(req, la, sizeof(la));
  89         } else
  90 #endif
  91                 return SYSCTL_OUT(req, &averunnable, sizeof(averunnable));
  92 }
  93 SYSCTL_PROC(_vm, VM_LOADAVG, loadavg, CTLTYPE_STRUCT | CTLFLAG_RD |
  94     CTLFLAG_MPSAFE, NULL, 0, sysctl_vm_loadavg, "S,loadavg",
  95     "Machine loadaverage history");
  96
  97 static int
  98 vmtotal(SYSCTL_HANDLER_ARGS)
  99 {
 100         struct proc *p;
 101         struct vmtotal total;
 102         vm_map_entry_t entry;
 103         vm_object_t object;
 104         vm_map_t map;
 105         int paging;
 106         struct thread *td;
 107         struct vmspace *vm;
 108
 109         bzero(&total, sizeof(total));
 110         /*
 111          * Mark all objects as inactive.
 112          */
 113         mtx_lock(&vm_object_list_mtx);
 114         TAILQ_FOREACH(object, &vm_object_list, object_list) {
 115                 if (!VM_OBJECT_TRYLOCK(object)) {
 116                         /*
 117                          * Avoid a lock-order reversal.  Consequently,
 118                          * the reported number of active pages may be
 119                          * greater than the actual number.
 120                          */
 121                         continue;
 122                 }
 123                 vm_object_clear_flag(object, OBJ_ACTIVE);
 124                 VM_OBJECT_UNLOCK(object);
 125         }
 126         mtx_unlock(&vm_object_list_mtx);
 127         /*
 128          * Calculate process statistics.
 129          */
 130         sx_slock(&allproc_lock);
 131         FOREACH_PROC_IN_SYSTEM(p) {
 132                 if (p->p_flag & P_SYSTEM)
 133                         continue;
 134                 PROC_LOCK(p);
 135                 switch (p->p_state) {
 136                 case PRS_NEW:
 137                         PROC_UNLOCK(p);
 138                         continue;
 139                         break;
 140                 default:
 141                         FOREACH_THREAD_IN_PROC(p, td) {
 142                                 thread_lock(td);
 143                                 switch (td->td_state) {
 144                                 case TDS_INHIBITED:
 145                                         if (TD_IS_SWAPPED(td))
 146                                                 total.t_sw++;
 147                                         else if (TD_IS_SLEEPING(td) &&
 148                                             td->td_priority <= PZERO)
 149                                                 total.t_dw++;
 150                                         else
 151                                                 total.t_sl++;
 152                                         break;
 153
 154                                 case TDS_CAN_RUN:
 155                                         total.t_sw++;
 156                                         break;
 157                                 case TDS_RUNQ:
 158                                 case TDS_RUNNING:
 159                                         total.t_rq++;
 160                                         thread_unlock(td);
 161                                         continue;
 162                                 default:
 163                                         break;
 164                                 }
 165                                 thread_unlock(td);
 166                         }
 167                 }
 168                 PROC_UNLOCK(p);
 169                 /*
 170                  * Note active objects.
 171                  */
 172                 paging = 0;
 173                 vm = vmspace_acquire_ref(p);
 174                 if (vm == NULL)
 175                         continue;
 176                 map = &vm->vm_map;
 177                 vm_map_lock_read(map);
 178                 for (entry = map->header.next;
 179                     entry != &map->header; entry = entry->next) {
 180                         if ((entry->eflags & MAP_ENTRY_IS_SUB_MAP) ||
 181                             (object = entry->object.vm_object) == NULL)
 182                                 continue;
 183                         VM_OBJECT_LOCK(object);
 184                         vm_object_set_flag(object, OBJ_ACTIVE);
 185                         paging |= object->paging_in_progress;
 186                         VM_OBJECT_UNLOCK(object);
 187                 }
 188                 vm_map_unlock_read(map);
 189                 vmspace_free(vm);
 190                 if (paging)
 191                         total.t_pw++;
 192         }
 193         sx_sunlock(&allproc_lock);
 194         /*
 195          * Calculate object memory usage statistics.
 196          */
 197         mtx_lock(&vm_object_list_mtx);
 198         TAILQ_FOREACH(object, &vm_object_list, object_list) {
 199                 /*
 200                  * Perform unsynchronized reads on the object to avoid
 201                  * a lock-order reversal.  In this case, the lack of
 202                  * synchronization should not impair the accuracy of
 203                  * the reported statistics.
 204                  */
 205                 if (object->type == OBJT_DEVICE || object->type == OBJT_SG) {
 206                         /*
 207                          * Devices, like /dev/mem, will badly skew our totals.
 208                          */
 209                         continue;
 210                 }
 211                 if (object->ref_count == 0) {
 212                         /*
 213                          * Also skip unreferenced objects, including
 214                          * vnodes representing mounted file systems.
 215                          */
 216                         continue;
 217                 }
 218                 total.t_vm += object->size;
 219                 total.t_rm += object->resident_page_count;
 220                 if (object->flags & OBJ_ACTIVE) {
 221                         total.t_avm += object->size;
 222                         total.t_arm += object->resident_page_count;
 223                 }
 224                 if (object->shadow_count > 1) {
 225                         /* shared object */
 226                         total.t_vmshr += object->size;
 227                         total.t_rmshr += object->resident_page_count;
 228                         if (object->flags & OBJ_ACTIVE) {
 229                                 total.t_avmshr += object->size;
 230                                 total.t_armshr += object->resident_page_count;
 231                         }
 232                 }
 233         }
 234         mtx_unlock(&vm_object_list_mtx);
 235         total.t_free = cnt.v_free_count + cnt.v_cache_count;
 236         return (sysctl_handle_opaque(oidp, &total, sizeof(total), req));
 237 }
 238
 239 /*
 240  * vcnt() -     accumulate statistics from all cpus and the global cnt
 241  *              structure.
 242  *
 243  *      The vmmeter structure is now per-cpu as well as global.  Those
 244  *      statistics which can be kept on a per-cpu basis (to avoid cache
 245  *      stalls between cpus) can be moved to the per-cpu vmmeter.  Remaining
 246  *      statistics, such as v_free_reserved, are left in the global
 247  *      structure.
 248  *
 249  * (sysctl_oid *oidp, void *arg1, int arg2, struct sysctl_req *req)
 250  */
 251 static int
 252 vcnt(SYSCTL_HANDLER_ARGS)
 253 {
 254         int count = *(int *)arg1;
 255         int offset = (char *)arg1 - (char *)&cnt;
 256 #ifdef SMP
 257         int i;
 258
 259         for (i = 0; i < mp_ncpus; ++i) {
 260                 struct pcpu *pcpu = pcpu_find(i);
 261                 count += *(int *)((char *)&pcpu->pc_cnt + offset);
 262         }
 263 #else
 264         count += *(int *)((char *)PCPU_PTR(cnt) + offset);
 265 #endif
 266         return (SYSCTL_OUT(req, &count, sizeof(int)));
 267 }
 268
 269 SYSCTL_PROC(_vm, VM_TOTAL, vmtotal, CTLTYPE_OPAQUE|CTLFLAG_RD|CTLFLAG_MPSAFE,
 270     0, sizeof(struct vmtotal), vmtotal, "S,vmtotal",
 271     "System virtual memory statistics");
 272 SYSCTL_NODE(_vm, OID_AUTO, stats, CTLFLAG_RW, 0, "VM meter stats");
 273 static SYSCTL_NODE(_vm_stats, OID_AUTO, sys, CTLFLAG_RW, 0,
 274         "VM meter sys stats");
 275 static SYSCTL_NODE(_vm_stats, OID_AUTO, vm, CTLFLAG_RW, 0,
 276         "VM meter vm stats");
 277 SYSCTL_NODE(_vm_stats, OID_AUTO, misc, CTLFLAG_RW, 0, "VM meter misc stats");
 278
 279 SYSCTL_PROC(_vm_stats_sys, OID_AUTO, v_swtch, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 280         &cnt.v_swtch, 0, vcnt, "IU", "Context switches");
 281 SYSCTL_PROC(_vm_stats_sys, OID_AUTO, v_trap, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 282         &cnt.v_trap, 0, vcnt, "IU", "Traps");
 283 SYSCTL_PROC(_vm_stats_sys, OID_AUTO, v_syscall, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 284         &cnt.v_syscall, 0, vcnt, "IU", "Syscalls");
 285 SYSCTL_PROC(_vm_stats_sys, OID_AUTO, v_intr, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 286         &cnt.v_intr, 0, vcnt, "IU", "Hardware interrupts");
 287 SYSCTL_PROC(_vm_stats_sys, OID_AUTO, v_soft, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 288         &cnt.v_soft, 0, vcnt, "IU", "Software interrupts");
 289 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_vm_faults, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 290         &cnt.v_vm_faults, 0, vcnt, "IU", "VM faults");
 291 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_cow_faults, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 292         &cnt.v_cow_faults, 0, vcnt, "IU", "COW faults");
 293 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_cow_optim, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 294         &cnt.v_cow_optim, 0, vcnt, "IU", "Optimized COW faults");
 295 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_zfod, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 296         &cnt.v_zfod, 0, vcnt, "IU", "Zero fill");
 297 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_ozfod, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 298         &cnt.v_ozfod, 0, vcnt, "IU", "Optimized zero fill");
 299 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_swapin, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 300         &cnt.v_swapin, 0, vcnt, "IU", "Swapin operations");
 301 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_swapout, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 302         &cnt.v_swapout, 0, vcnt, "IU", "Swapout operations");
 303 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_swappgsin, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 304         &cnt.v_swappgsin, 0, vcnt, "IU", "Swapin pages");
 305 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_swappgsout, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 306         &cnt.v_swappgsout, 0, vcnt, "IU", "Swapout pages");
 307 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_vnodein, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 308         &cnt.v_vnodein, 0, vcnt, "IU", "Vnodein operations");
 309 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_vnodeout, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 310         &cnt.v_vnodeout, 0, vcnt, "IU", "Vnodeout operations");
 311 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_vnodepgsin, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 312         &cnt.v_vnodepgsin, 0, vcnt, "IU", "Vnodein pages");
 313 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_vnodepgsout, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 314         &cnt.v_vnodepgsout, 0, vcnt, "IU", "Vnodeout pages");
 315 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_intrans, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 316         &cnt.v_intrans, 0, vcnt, "IU", "In transit page blocking");
 317 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_reactivated, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 318         &cnt.v_reactivated, 0, vcnt, "IU", "Reactivated pages");
 319 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_pdwakeups, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 320         &cnt.v_pdwakeups, 0, vcnt, "IU", "Pagedaemon wakeups");
 321 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_pdpages, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 322         &cnt.v_pdpages, 0, vcnt, "IU", "Pagedaemon page scans");
 323 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_tcached, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 324         &cnt.v_tcached, 0, vcnt, "IU", "Total pages cached");
 325 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_dfree, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 326         &cnt.v_dfree, 0, vcnt, "IU", "");
 327 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_pfree, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 328         &cnt.v_pfree, 0, vcnt, "IU", "");
 329 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_tfree, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 330         &cnt.v_tfree, 0, vcnt, "IU", "");
 331 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_page_size, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 332         &cnt.v_page_size, 0, vcnt, "IU", "");
 333 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_page_count, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 334         &cnt.v_page_count, 0, vcnt, "IU", "");
 335 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_free_reserved, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 336         &cnt.v_free_reserved, 0, vcnt, "IU", "");
 337 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_free_target, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 338         &cnt.v_free_target, 0, vcnt, "IU", "");
 339 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_free_min, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 340         &cnt.v_free_min, 0, vcnt, "IU", "");
 341 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_free_count, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 342         &cnt.v_free_count, 0, vcnt, "IU", "");
 343 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_wire_count, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 344         &cnt.v_wire_count, 0, vcnt, "IU", "");
 345 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_active_count, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 346         &cnt.v_active_count, 0, vcnt, "IU", "");
 347 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_inactive_target, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 348         &cnt.v_inactive_target, 0, vcnt, "IU", "");
 349 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_inactive_count, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 350         &cnt.v_inactive_count, 0, vcnt, "IU", "");
 351 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_cache_count, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 352         &cnt.v_cache_count, 0, vcnt, "IU", "");
 353 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_cache_min, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 354         &cnt.v_cache_min, 0, vcnt, "IU", "");
 355 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_cache_max, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 356         &cnt.v_cache_max, 0, vcnt, "IU", "");
 357 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_pageout_free_min, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 358         &cnt.v_pageout_free_min, 0, vcnt, "IU", "");
 359 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_interrupt_free_min, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 360         &cnt.v_interrupt_free_min, 0, vcnt, "IU", "");
 361 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_forks, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 362         &cnt.v_forks, 0, vcnt, "IU", "Number of fork() calls");
 363 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_vforks, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 364         &cnt.v_vforks, 0, vcnt, "IU", "Number of vfork() calls");
 365 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_rforks, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 366         &cnt.v_rforks, 0, vcnt, "IU", "Number of rfork() calls");
 367 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_kthreads, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 368         &cnt.v_kthreads, 0, vcnt, "IU", "Number of fork() calls by kernel");
 369 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_forkpages, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 370         &cnt.v_forkpages, 0, vcnt, "IU", "VM pages affected by fork()");
 371 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_vforkpages, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 372         &cnt.v_vforkpages, 0, vcnt, "IU", "VM pages affected by vfork()");
 373 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_rforkpages, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 374         &cnt.v_rforkpages, 0, vcnt, "IU", "VM pages affected by rfork()");
 375 SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_kthreadpages, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
 376         &cnt.v_kthreadpages, 0, vcnt, "IU", "VM pages affected by fork() by kernel");
 377
 378 SYSCTL_INT(_vm_stats_misc, OID_AUTO,
 379         zero_page_count, CTLFLAG_RD, &vm_page_zero_count, 0, "");