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/rwlock.h>
  43 #include <sys/sx.h>
  44 #include <sys/vmmeter.h>
  45 #include <sys/smp.h>
  46
  47 #include <vm/vm.h>
  48 #include <vm/vm_page.h>
  49 #include <vm/vm_extern.h>
  50 #include <vm/vm_param.h>
  51 #include <vm/pmap.h>
  52 #include <vm/vm_map.h>
  53 #include <vm/vm_object.h>
  54 #include <sys/sysctl.h>
  55
  56 struct vmmeter vm_cnt;
  57
  58 SYSCTL_UINT(_vm, VM_V_FREE_MIN, v_free_min,
  59         CTLFLAG_RW, &vm_cnt.v_free_min, 0, "Minimum low-free-pages threshold");
  60 SYSCTL_UINT(_vm, VM_V_FREE_TARGET, v_free_target,
  61         CTLFLAG_RW, &vm_cnt.v_free_target, 0, "Desired free pages");
  62 SYSCTL_UINT(_vm, VM_V_FREE_RESERVED, v_free_reserved,
  63         CTLFLAG_RW, &vm_cnt.v_free_reserved, 0, "Pages reserved for deadlock");
  64 SYSCTL_UINT(_vm, VM_V_INACTIVE_TARGET, v_inactive_target,
  65         CTLFLAG_RW, &vm_cnt.v_inactive_target, 0, "Pages desired inactive");
  66 SYSCTL_UINT(_vm, VM_V_PAGEOUT_FREE_MIN, v_pageout_free_min,
  67         CTLFLAG_RW, &vm_cnt.v_pageout_free_min, 0, "Min pages reserved for kernel");
  68 SYSCTL_UINT(_vm, OID_AUTO, v_free_severe,
  69         CTLFLAG_RW, &vm_cnt.v_free_severe, 0, "Severe page depletion point");
  70
  71 static int
  72 sysctl_vm_loadavg(SYSCTL_HANDLER_ARGS)
  73 {
  74
  75 #ifdef SCTL_MASK32
  76         u_int32_t la[4];
  77
  78         if (req->flags & SCTL_MASK32) {
  79                 la[0] = averunnable.ldavg[0];
  80                 la[1] = averunnable.ldavg[1];
  81                 la[2] = averunnable.ldavg[2];
  82                 la[3] = averunnable.fscale;
  83                 return SYSCTL_OUT(req, la, sizeof(la));
  84         } else
  85 #endif
  86                 return SYSCTL_OUT(req, &averunnable, sizeof(averunnable));
  87 }
  88 SYSCTL_PROC(_vm, VM_LOADAVG, loadavg, CTLTYPE_STRUCT | CTLFLAG_RD |
  89     CTLFLAG_MPSAFE, NULL, 0, sysctl_vm_loadavg, "S,loadavg",
  90     "Machine loadaverage history");
  91
  92 /*
  93  * This function aims to determine if the object is mapped,
  94  * specifically, if it is referenced by a vm_map_entry.  Because
  95  * objects occasionally acquire transient references that do not
  96  * represent a mapping, the method used here is inexact.  However, it
  97  * has very low overhead and is good enough for the advisory
  98  * vm.vmtotal sysctl.
  99  */
 100 static bool
 101 is_object_active(vm_object_t obj)
 102 {
 103
 104         return (obj->ref_count > obj->shadow_count);
 105 }
 106
 107 static int
 108 vmtotal(SYSCTL_HANDLER_ARGS)
 109 {
 110         struct vmtotal total;
 111         vm_object_t object;
 112         struct proc *p;
 113         struct thread *td;
 114
 115         bzero(&total, sizeof(total));
 116
 117         /*
 118          * Calculate process statistics.
 119          */
 120         sx_slock(&allproc_lock);
 121         FOREACH_PROC_IN_SYSTEM(p) {
 122                 if ((p->p_flag & P_SYSTEM) != 0)
 123                         continue;
 124                 PROC_LOCK(p);
 125                 if (p->p_state != PRS_NEW) {
 126                         FOREACH_THREAD_IN_PROC(p, td) {
 127                                 thread_lock(td);
 128                                 switch (td->td_state) {
 129                                 case TDS_INHIBITED:
 130                                         if (TD_IS_SWAPPED(td))
 131                                                 total.t_sw++;
 132                                         else if (TD_IS_SLEEPING(td)) {
 133                                                 if (td->td_priority <= PZERO)
 134                                                         total.t_dw++;
 135                                                 else
 136                                                         total.t_sl++;
 137                                                 if (td->td_wchan ==
 138                                                     &vm_cnt.v_free_count)
 139                                                         total.t_pw++;
 140                                         }
 141                                         break;
 142                                 case TDS_CAN_RUN:
 143                                         total.t_sw++;
 144                                         break;
 145                                 case TDS_RUNQ:
 146                                 case TDS_RUNNING:
 147                                         total.t_rq++;
 148                                         break;
 149                                 default:
 150                                         break;
 151                                 }
 152                                 thread_unlock(td);
 153                         }
 154                 }
 155                 PROC_UNLOCK(p);
 156         }
 157         sx_sunlock(&allproc_lock);
 158         /*
 159          * Calculate object memory usage statistics.
 160          */
 161         mtx_lock(&vm_object_list_mtx);
 162         TAILQ_FOREACH(object, &vm_object_list, object_list) {
 163                 /*
 164                  * Perform unsynchronized reads on the object.  In
 165                  * this case, the lack of synchronization should not
 166                  * impair the accuracy of the reported statistics.
 167                  */
 168                 if ((object->flags & OBJ_FICTITIOUS) != 0) {
 169                         /*
 170                          * Devices, like /dev/mem, will badly skew our totals.
 171                          */
 172                         continue;
 173                 }
 174                 if (object->ref_count == 0) {
 175                         /*
 176                          * Also skip unreferenced objects, including
 177                          * vnodes representing mounted file systems.
 178                          */
 179                         continue;
 180                 }
 181                 if (object->ref_count == 1 &&
 182                     (object->flags & OBJ_NOSPLIT) != 0) {
 183                         /*
 184                          * Also skip otherwise unreferenced swap
 185                          * objects backing tmpfs vnodes, and POSIX or
 186                          * SysV shared memory.
 187                          */
 188                         continue;
 189                 }
 190                 total.t_vm += object->size;
 191                 total.t_rm += object->resident_page_count;
 192                 if (is_object_active(object)) {
 193                         total.t_avm += object->size;
 194                         total.t_arm += object->resident_page_count;
 195                 }
 196                 if (object->shadow_count > 1) {
 197                         /* shared object */
 198                         total.t_vmshr += object->size;
 199                         total.t_rmshr += object->resident_page_count;
 200                         if (is_object_active(object)) {
 201                                 total.t_avmshr += object->size;
 202                                 total.t_armshr += object->resident_page_count;
 203                         }
 204                 }
 205         }
 206         mtx_unlock(&vm_object_list_mtx);
 207         total.t_free = vm_cnt.v_free_count;
 208         return (sysctl_handle_opaque(oidp, &total, sizeof(total), req));
 209 }
 210
 211 /*
 212  * vm_meter_cnt() -     accumulate statistics from all cpus and the global cnt
 213  *                      structure.
 214  *
 215  *      The vmmeter structure is now per-cpu as well as global.  Those
 216  *      statistics which can be kept on a per-cpu basis (to avoid cache
 217  *      stalls between cpus) can be moved to the per-cpu vmmeter.  Remaining
 218  *      statistics, such as v_free_reserved, are left in the global
 219  *      structure.
 220  */
 221 u_int
 222 vm_meter_cnt(size_t offset)
 223 {
 224         struct pcpu *pcpu;
 225         u_int count;
 226         int i;
 227
 228         count = *(u_int *)((char *)&vm_cnt + offset);
 229         CPU_FOREACH(i) {
 230                 pcpu = pcpu_find(i);
 231                 count += *(u_int *)((char *)&pcpu->pc_cnt + offset);
 232         }
 233         return (count);
 234 }
 235
 236 static int
 237 cnt_sysctl(SYSCTL_HANDLER_ARGS)
 238 {
 239         u_int count;
 240
 241         count = vm_meter_cnt((char *)arg1 - (char *)&vm_cnt);
 242         return (SYSCTL_OUT(req, &count, sizeof(count)));
 243 }
 244
 245 SYSCTL_PROC(_vm, VM_TOTAL, vmtotal, CTLTYPE_OPAQUE|CTLFLAG_RD|CTLFLAG_MPSAFE,
 246     0, sizeof(struct vmtotal), vmtotal, "S,vmtotal",
 247     "System virtual memory statistics");
 248 SYSCTL_NODE(_vm, OID_AUTO, stats, CTLFLAG_RW, 0, "VM meter stats");
 249 static SYSCTL_NODE(_vm_stats, OID_AUTO, sys, CTLFLAG_RW, 0,
 250         "VM meter sys stats");
 251 static SYSCTL_NODE(_vm_stats, OID_AUTO, vm, CTLFLAG_RW, 0,
 252         "VM meter vm stats");
 253 SYSCTL_NODE(_vm_stats, OID_AUTO, misc, CTLFLAG_RW, 0, "VM meter misc stats");
 254
 255 #define VM_STATS(parent, var, descr) \
 256         SYSCTL_PROC(parent, OID_AUTO, var, \
 257             CTLTYPE_UINT | CTLFLAG_RD | CTLFLAG_MPSAFE, &vm_cnt.var, 0, \
 258             cnt_sysctl, "IU", descr)
 259 #define VM_STATS_VM(var, descr)         VM_STATS(_vm_stats_vm, var, descr)
 260 #define VM_STATS_SYS(var, descr)        VM_STATS(_vm_stats_sys, var, descr)
 261
 262 VM_STATS_SYS(v_swtch, "Context switches");
 263 VM_STATS_SYS(v_trap, "Traps");
 264 VM_STATS_SYS(v_syscall, "System calls");
 265 VM_STATS_SYS(v_intr, "Device interrupts");
 266 VM_STATS_SYS(v_soft, "Software interrupts");
 267 VM_STATS_VM(v_vm_faults, "Address memory faults");
 268 VM_STATS_VM(v_io_faults, "Page faults requiring I/O");
 269 VM_STATS_VM(v_cow_faults, "Copy-on-write faults");
 270 VM_STATS_VM(v_cow_optim, "Optimized COW faults");
 271 VM_STATS_VM(v_zfod, "Pages zero-filled on demand");
 272 VM_STATS_VM(v_ozfod, "Optimized zero fill pages");
 273 VM_STATS_VM(v_swapin, "Swap pager pageins");
 274 VM_STATS_VM(v_swapout, "Swap pager pageouts");
 275 VM_STATS_VM(v_swappgsin, "Swap pages swapped in");
 276 VM_STATS_VM(v_swappgsout, "Swap pages swapped out");
 277 VM_STATS_VM(v_vnodein, "Vnode pager pageins");
 278 VM_STATS_VM(v_vnodeout, "Vnode pager pageouts");
 279 VM_STATS_VM(v_vnodepgsin, "Vnode pages paged in");
 280 VM_STATS_VM(v_vnodepgsout, "Vnode pages paged out");
 281 VM_STATS_VM(v_intrans, "In transit page faults");
 282 VM_STATS_VM(v_reactivated, "Pages reactivated by pagedaemon");
 283 VM_STATS_VM(v_pdwakeups, "Pagedaemon wakeups");
 284 VM_STATS_VM(v_pdpages, "Pages analyzed by pagedaemon");
 285 VM_STATS_VM(v_pdshortfalls, "Page reclamation shortfalls");
 286 VM_STATS_VM(v_tcached, "Total pages cached");
 287 VM_STATS_VM(v_dfree, "Pages freed by pagedaemon");
 288 VM_STATS_VM(v_pfree, "Pages freed by exiting processes");
 289 VM_STATS_VM(v_tfree, "Total pages freed");
 290 VM_STATS_VM(v_page_size, "Page size in bytes");
 291 VM_STATS_VM(v_page_count, "Total number of pages in system");
 292 VM_STATS_VM(v_free_reserved, "Pages reserved for deadlock");
 293 VM_STATS_VM(v_free_target, "Pages desired free");
 294 VM_STATS_VM(v_free_min, "Minimum low-free-pages threshold");
 295 VM_STATS_VM(v_free_count, "Free pages");
 296 VM_STATS_VM(v_wire_count, "Wired pages");
 297 VM_STATS_VM(v_active_count, "Active pages");
 298 VM_STATS_VM(v_inactive_target, "Desired inactive pages");
 299 VM_STATS_VM(v_inactive_count, "Inactive pages");
 300 VM_STATS_VM(v_laundry_count, "Pages eligible for laundering");
 301 VM_STATS_VM(v_cache_count, "Pages on cache queue");
 302 VM_STATS_VM(v_pageout_free_min, "Min pages reserved for kernel");
 303 VM_STATS_VM(v_interrupt_free_min, "Reserved pages for interrupt code");
 304 VM_STATS_VM(v_forks, "Number of fork() calls");
 305 VM_STATS_VM(v_vforks, "Number of vfork() calls");
 306 VM_STATS_VM(v_rforks, "Number of rfork() calls");
 307 VM_STATS_VM(v_kthreads, "Number of fork() calls by kernel");
 308 VM_STATS_VM(v_forkpages, "VM pages affected by fork()");
 309 VM_STATS_VM(v_vforkpages, "VM pages affected by vfork()");
 310 VM_STATS_VM(v_rforkpages, "VM pages affected by rfork()");
 311 VM_STATS_VM(v_kthreadpages, "VM pages affected by fork() by kernel");
 312
 313 SYSCTL_INT(_vm_stats_misc, OID_AUTO, zero_page_count, CTLFLAG_RD,
 314         &vm_page_zero_count, 0, "Number of zero-ed free pages");