freebsd-dev/sys/vm/vm_meter.c
John Baldwin e735691b61 Place VM objects on the object list when created and never remove them.
This is ok since objects come from a NOFREE zone and allows objects to
be locked while traversing the object list without triggering a LOR.

Ensure that objects on the list are marked DEAD while free or stillborn,
and that they have a refcount of zero.  This required updating most of
the pagers to explicitly mark an object as dead when deallocating it.
(Only the vnode pager did this previously.)

Differential Revision:	https://reviews.freebsd.org/D2423
Reviewed by:	alc, kib (earlier version)
MFC after:	2 weeks
Sponsored by:	Norse Corp, Inc.
2015-05-08 19:43:37 +00:00

326 lines
11 KiB
C

/*-
* Copyright (c) 1982, 1986, 1989, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)vm_meter.c 8.4 (Berkeley) 1/4/94
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/proc.h>
#include <sys/resource.h>
#include <sys/rwlock.h>
#include <sys/sx.h>
#include <sys/vmmeter.h>
#include <sys/smp.h>
#include <vm/vm.h>
#include <vm/vm_page.h>
#include <vm/vm_extern.h>
#include <vm/vm_param.h>
#include <vm/pmap.h>
#include <vm/vm_map.h>
#include <vm/vm_object.h>
#include <sys/sysctl.h>
struct vmmeter vm_cnt;
SYSCTL_UINT(_vm, VM_V_FREE_MIN, v_free_min,
CTLFLAG_RW, &vm_cnt.v_free_min, 0, "Minimum low-free-pages threshold");
SYSCTL_UINT(_vm, VM_V_FREE_TARGET, v_free_target,
CTLFLAG_RW, &vm_cnt.v_free_target, 0, "Desired free pages");
SYSCTL_UINT(_vm, VM_V_FREE_RESERVED, v_free_reserved,
CTLFLAG_RW, &vm_cnt.v_free_reserved, 0, "Pages reserved for deadlock");
SYSCTL_UINT(_vm, VM_V_INACTIVE_TARGET, v_inactive_target,
CTLFLAG_RW, &vm_cnt.v_inactive_target, 0, "Pages desired inactive");
SYSCTL_UINT(_vm, VM_V_CACHE_MIN, v_cache_min,
CTLFLAG_RW, &vm_cnt.v_cache_min, 0, "Min pages on cache queue");
SYSCTL_UINT(_vm, VM_V_CACHE_MAX, v_cache_max,
CTLFLAG_RW, &vm_cnt.v_cache_max, 0, "Max pages on cache queue");
SYSCTL_UINT(_vm, VM_V_PAGEOUT_FREE_MIN, v_pageout_free_min,
CTLFLAG_RW, &vm_cnt.v_pageout_free_min, 0, "Min pages reserved for kernel");
SYSCTL_UINT(_vm, OID_AUTO, v_free_severe,
CTLFLAG_RW, &vm_cnt.v_free_severe, 0, "Severe page depletion point");
static int
sysctl_vm_loadavg(SYSCTL_HANDLER_ARGS)
{
#ifdef SCTL_MASK32
u_int32_t la[4];
if (req->flags & SCTL_MASK32) {
la[0] = averunnable.ldavg[0];
la[1] = averunnable.ldavg[1];
la[2] = averunnable.ldavg[2];
la[3] = averunnable.fscale;
return SYSCTL_OUT(req, la, sizeof(la));
} else
#endif
return SYSCTL_OUT(req, &averunnable, sizeof(averunnable));
}
SYSCTL_PROC(_vm, VM_LOADAVG, loadavg, CTLTYPE_STRUCT | CTLFLAG_RD |
CTLFLAG_MPSAFE, NULL, 0, sysctl_vm_loadavg, "S,loadavg",
"Machine loadaverage history");
static int
vmtotal(SYSCTL_HANDLER_ARGS)
{
struct proc *p;
struct vmtotal total;
vm_map_entry_t entry;
vm_object_t object;
vm_map_t map;
int paging;
struct thread *td;
struct vmspace *vm;
bzero(&total, sizeof(total));
/*
* Mark all objects as inactive.
*/
mtx_lock(&vm_object_list_mtx);
TAILQ_FOREACH(object, &vm_object_list, object_list) {
VM_OBJECT_WLOCK(object);
vm_object_clear_flag(object, OBJ_ACTIVE);
VM_OBJECT_WUNLOCK(object);
}
mtx_unlock(&vm_object_list_mtx);
/*
* Calculate process statistics.
*/
sx_slock(&allproc_lock);
FOREACH_PROC_IN_SYSTEM(p) {
if (p->p_flag & P_SYSTEM)
continue;
PROC_LOCK(p);
switch (p->p_state) {
case PRS_NEW:
PROC_UNLOCK(p);
continue;
break;
default:
FOREACH_THREAD_IN_PROC(p, td) {
thread_lock(td);
switch (td->td_state) {
case TDS_INHIBITED:
if (TD_IS_SWAPPED(td))
total.t_sw++;
else if (TD_IS_SLEEPING(td) &&
td->td_priority <= PZERO)
total.t_dw++;
else
total.t_sl++;
break;
case TDS_CAN_RUN:
total.t_sw++;
break;
case TDS_RUNQ:
case TDS_RUNNING:
total.t_rq++;
thread_unlock(td);
continue;
default:
break;
}
thread_unlock(td);
}
}
PROC_UNLOCK(p);
/*
* Note active objects.
*/
paging = 0;
vm = vmspace_acquire_ref(p);
if (vm == NULL)
continue;
map = &vm->vm_map;
vm_map_lock_read(map);
for (entry = map->header.next;
entry != &map->header; entry = entry->next) {
if ((entry->eflags & MAP_ENTRY_IS_SUB_MAP) ||
(object = entry->object.vm_object) == NULL)
continue;
VM_OBJECT_WLOCK(object);
vm_object_set_flag(object, OBJ_ACTIVE);
paging |= object->paging_in_progress;
VM_OBJECT_WUNLOCK(object);
}
vm_map_unlock_read(map);
vmspace_free(vm);
if (paging)
total.t_pw++;
}
sx_sunlock(&allproc_lock);
/*
* Calculate object memory usage statistics.
*/
mtx_lock(&vm_object_list_mtx);
TAILQ_FOREACH(object, &vm_object_list, object_list) {
/*
* Perform unsynchronized reads on the object. In
* this case, the lack of synchronization should not
* impair the accuracy of the reported statistics.
*/
if ((object->flags & OBJ_FICTITIOUS) != 0) {
/*
* Devices, like /dev/mem, will badly skew our totals.
*/
continue;
}
if (object->ref_count == 0) {
/*
* Also skip unreferenced objects, including
* vnodes representing mounted file systems.
*/
continue;
}
total.t_vm += object->size;
total.t_rm += object->resident_page_count;
if (object->flags & OBJ_ACTIVE) {
total.t_avm += object->size;
total.t_arm += object->resident_page_count;
}
if (object->shadow_count > 1) {
/* shared object */
total.t_vmshr += object->size;
total.t_rmshr += object->resident_page_count;
if (object->flags & OBJ_ACTIVE) {
total.t_avmshr += object->size;
total.t_armshr += object->resident_page_count;
}
}
}
mtx_unlock(&vm_object_list_mtx);
total.t_free = vm_cnt.v_free_count + vm_cnt.v_cache_count;
return (sysctl_handle_opaque(oidp, &total, sizeof(total), req));
}
/*
* vcnt() - accumulate statistics from all cpus and the global cnt
* structure.
*
* The vmmeter structure is now per-cpu as well as global. Those
* statistics which can be kept on a per-cpu basis (to avoid cache
* stalls between cpus) can be moved to the per-cpu vmmeter. Remaining
* statistics, such as v_free_reserved, are left in the global
* structure.
*
* (sysctl_oid *oidp, void *arg1, int arg2, struct sysctl_req *req)
*/
static int
vcnt(SYSCTL_HANDLER_ARGS)
{
int count = *(int *)arg1;
int offset = (char *)arg1 - (char *)&vm_cnt;
int i;
CPU_FOREACH(i) {
struct pcpu *pcpu = pcpu_find(i);
count += *(int *)((char *)&pcpu->pc_cnt + offset);
}
return (SYSCTL_OUT(req, &count, sizeof(int)));
}
SYSCTL_PROC(_vm, VM_TOTAL, vmtotal, CTLTYPE_OPAQUE|CTLFLAG_RD|CTLFLAG_MPSAFE,
0, sizeof(struct vmtotal), vmtotal, "S,vmtotal",
"System virtual memory statistics");
SYSCTL_NODE(_vm, OID_AUTO, stats, CTLFLAG_RW, 0, "VM meter stats");
static SYSCTL_NODE(_vm_stats, OID_AUTO, sys, CTLFLAG_RW, 0,
"VM meter sys stats");
static SYSCTL_NODE(_vm_stats, OID_AUTO, vm, CTLFLAG_RW, 0,
"VM meter vm stats");
SYSCTL_NODE(_vm_stats, OID_AUTO, misc, CTLFLAG_RW, 0, "VM meter misc stats");
#define VM_STATS(parent, var, descr) \
SYSCTL_PROC(parent, OID_AUTO, var, \
CTLTYPE_UINT | CTLFLAG_RD | CTLFLAG_MPSAFE, &vm_cnt.var, 0, vcnt, \
"IU", descr)
#define VM_STATS_VM(var, descr) VM_STATS(_vm_stats_vm, var, descr)
#define VM_STATS_SYS(var, descr) VM_STATS(_vm_stats_sys, var, descr)
VM_STATS_SYS(v_swtch, "Context switches");
VM_STATS_SYS(v_trap, "Traps");
VM_STATS_SYS(v_syscall, "System calls");
VM_STATS_SYS(v_intr, "Device interrupts");
VM_STATS_SYS(v_soft, "Software interrupts");
VM_STATS_VM(v_vm_faults, "Address memory faults");
VM_STATS_VM(v_io_faults, "Page faults requiring I/O");
VM_STATS_VM(v_cow_faults, "Copy-on-write faults");
VM_STATS_VM(v_cow_optim, "Optimized COW faults");
VM_STATS_VM(v_zfod, "Pages zero-filled on demand");
VM_STATS_VM(v_ozfod, "Optimized zero fill pages");
VM_STATS_VM(v_swapin, "Swap pager pageins");
VM_STATS_VM(v_swapout, "Swap pager pageouts");
VM_STATS_VM(v_swappgsin, "Swap pages swapped in");
VM_STATS_VM(v_swappgsout, "Swap pages swapped out");
VM_STATS_VM(v_vnodein, "Vnode pager pageins");
VM_STATS_VM(v_vnodeout, "Vnode pager pageouts");
VM_STATS_VM(v_vnodepgsin, "Vnode pages paged in");
VM_STATS_VM(v_vnodepgsout, "Vnode pages paged out");
VM_STATS_VM(v_intrans, "In transit page faults");
VM_STATS_VM(v_reactivated, "Pages reactivated from free list");
VM_STATS_VM(v_pdwakeups, "Pagedaemon wakeups");
VM_STATS_VM(v_pdpages, "Pages analyzed by pagedaemon");
VM_STATS_VM(v_tcached, "Total pages cached");
VM_STATS_VM(v_dfree, "Pages freed by pagedaemon");
VM_STATS_VM(v_pfree, "Pages freed by exiting processes");
VM_STATS_VM(v_tfree, "Total pages freed");
VM_STATS_VM(v_page_size, "Page size in bytes");
VM_STATS_VM(v_page_count, "Total number of pages in system");
VM_STATS_VM(v_free_reserved, "Pages reserved for deadlock");
VM_STATS_VM(v_free_target, "Pages desired free");
VM_STATS_VM(v_free_min, "Minimum low-free-pages threshold");
VM_STATS_VM(v_free_count, "Free pages");
VM_STATS_VM(v_wire_count, "Wired pages");
VM_STATS_VM(v_active_count, "Active pages");
VM_STATS_VM(v_inactive_target, "Desired inactive pages");
VM_STATS_VM(v_inactive_count, "Inactive pages");
VM_STATS_VM(v_cache_count, "Pages on cache queue");
VM_STATS_VM(v_cache_min, "Min pages on cache queue");
VM_STATS_VM(v_cache_max, "Max pages on cached queue");
VM_STATS_VM(v_pageout_free_min, "Min pages reserved for kernel");
VM_STATS_VM(v_interrupt_free_min, "Reserved pages for interrupt code");
VM_STATS_VM(v_forks, "Number of fork() calls");
VM_STATS_VM(v_vforks, "Number of vfork() calls");
VM_STATS_VM(v_rforks, "Number of rfork() calls");
VM_STATS_VM(v_kthreads, "Number of fork() calls by kernel");
VM_STATS_VM(v_forkpages, "VM pages affected by fork()");
VM_STATS_VM(v_vforkpages, "VM pages affected by vfork()");
VM_STATS_VM(v_rforkpages, "VM pages affected by rfork()");
VM_STATS_VM(v_kthreadpages, "VM pages affected by fork() by kernel");
SYSCTL_INT(_vm_stats_misc, OID_AUTO, zero_page_count, CTLFLAG_RD,
&vm_page_zero_count, 0, "Number of zero-ed free pages");