freebsd-dev/sys/vm/vm_meter.c

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/*-
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* 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
*/
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#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
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#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/sx.h>
#include <sys/vmmeter.h>
#include <sys/smp.h>
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#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>
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#include <sys/sysctl.h>
struct vmmeter cnt;
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int maxslp = MAXSLP;
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SYSCTL_UINT(_vm, VM_V_FREE_MIN, v_free_min,
CTLFLAG_RW, &cnt.v_free_min, 0, "");
SYSCTL_UINT(_vm, VM_V_FREE_TARGET, v_free_target,
CTLFLAG_RW, &cnt.v_free_target, 0, "");
SYSCTL_UINT(_vm, VM_V_FREE_RESERVED, v_free_reserved,
CTLFLAG_RW, &cnt.v_free_reserved, 0, "");
SYSCTL_UINT(_vm, VM_V_INACTIVE_TARGET, v_inactive_target,
CTLFLAG_RW, &cnt.v_inactive_target, 0, "");
SYSCTL_UINT(_vm, VM_V_CACHE_MIN, v_cache_min,
CTLFLAG_RW, &cnt.v_cache_min, 0, "");
SYSCTL_UINT(_vm, VM_V_CACHE_MAX, v_cache_max,
CTLFLAG_RW, &cnt.v_cache_max, 0, "");
SYSCTL_UINT(_vm, VM_V_PAGEOUT_FREE_MIN, v_pageout_free_min,
CTLFLAG_RW, &cnt.v_pageout_free_min, 0, "");
SYSCTL_UINT(_vm, OID_AUTO, v_free_severe,
CTLFLAG_RW, &cnt.v_free_severe, 0, "");
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,
NULL, 0, sysctl_vm_loadavg, "S,loadavg", "Machine loadaverage history");
static int
vmtotal(SYSCTL_HANDLER_ARGS)
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{
/* XXXKSE almost completely broken */
struct proc *p;
struct vmtotal total;
vm_map_entry_t entry;
vm_object_t object;
vm_map_t map;
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int paging;
struct thread *td;
struct vmspace *vm;
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bzero(&total, sizeof(total));
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/*
* Mark all objects as inactive.
*/
GIANT_REQUIRED;
mtx_lock(&vm_object_list_mtx);
TAILQ_FOREACH(object, &vm_object_list, object_list) {
if (!VM_OBJECT_TRYLOCK(object)) {
/*
* Avoid a lock-order reversal. Consequently,
* the reported number of active pages may be
* greater than the actual number.
*/
continue;
}
vm_object_clear_flag(object, OBJ_ACTIVE);
VM_OBJECT_UNLOCK(object);
}
mtx_unlock(&vm_object_list_mtx);
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/*
* Calculate process statistics.
*/
sx_slock(&allproc_lock);
FOREACH_PROC_IN_SYSTEM(p) {
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if (p->p_flag & P_SYSTEM)
continue;
PROC_SLOCK(p);
switch (p->p_state) {
case PRS_NEW:
PROC_SUNLOCK(p);
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continue;
break;
default:
FOREACH_THREAD_IN_PROC(p, td) {
/* Need new statistics XXX */
thread_lock(td);
switch (td->td_state) {
case TDS_INHIBITED:
/*
* XXX stats no longer synchronized.
*/
if (TD_ON_LOCK(td) ||
(td->td_inhibitors ==
TDI_SWAPPED)) {
total.t_sw++;
} else if (TD_IS_SLEEPING(td) ||
TD_AWAITING_INTR(td) ||
TD_IS_SUSPENDED(td)) {
if (td->td_priority <= PZERO)
total.t_dw++;
else
total.t_sl++;
}
break;
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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);
}
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}
PROC_SUNLOCK(p);
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/*
* 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;
These changes embody the support of the fully coherent merged VM buffer cache, much higher filesystem I/O performance, and much better paging performance. It represents the culmination of over 6 months of R&D. The majority of the merged VM/cache work is by John Dyson. The following highlights the most significant changes. Additionally, there are (mostly minor) changes to the various filesystem modules (nfs, msdosfs, etc) to support the new VM/buffer scheme. vfs_bio.c: Significant rewrite of most of vfs_bio to support the merged VM buffer cache scheme. The scheme is almost fully compatible with the old filesystem interface. Significant improvement in the number of opportunities for write clustering. vfs_cluster.c, vfs_subr.c Upgrade and performance enhancements in vfs layer code to support merged VM/buffer cache. Fixup of vfs_cluster to eliminate the bogus pagemove stuff. vm_object.c: Yet more improvements in the collapse code. Elimination of some windows that can cause list corruption. vm_pageout.c: Fixed it, it really works better now. Somehow in 2.0, some "enhancements" broke the code. This code has been reworked from the ground-up. vm_fault.c, vm_page.c, pmap.c, vm_object.c Support for small-block filesystems with merged VM/buffer cache scheme. pmap.c vm_map.c Dynamic kernel VM size, now we dont have to pre-allocate excessive numbers of kernel PTs. vm_glue.c Much simpler and more effective swapping code. No more gratuitous swapping. proc.h Fixed the problem that the p_lock flag was not being cleared on a fork. swap_pager.c, vnode_pager.c Removal of old vfs_bio cruft to support the past pseudo-coherency. Now the code doesn't need it anymore. machdep.c Changes to better support the parameter values for the merged VM/buffer cache scheme. machdep.c, kern_exec.c, vm_glue.c Implemented a seperate submap for temporary exec string space and another one to contain process upages. This eliminates all map fragmentation problems that previously existed. ffs_inode.c, ufs_inode.c, ufs_readwrite.c Changes for merged VM/buffer cache. Add "bypass" support for sneaking in on busy buffers. Submitted by: John Dyson and David Greenman
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entry != &map->header; entry = entry->next) {
if ((entry->eflags & MAP_ENTRY_IS_SUB_MAP) ||
(object = entry->object.vm_object) == NULL)
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continue;
VM_OBJECT_LOCK(object);
vm_object_set_flag(object, OBJ_ACTIVE);
paging |= object->paging_in_progress;
VM_OBJECT_UNLOCK(object);
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}
vm_map_unlock_read(map);
vmspace_free(vm);
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if (paging)
total.t_pw++;
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}
sx_sunlock(&allproc_lock);
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/*
* 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 to avoid
* a lock-order reversal. In this case, the lack of
* synchronization should not impair the accuracy of
* the reported statistics.
*/
if (object->type == OBJT_DEVICE) {
/*
* 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;
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if (object->flags & OBJ_ACTIVE) {
total.t_avm += object->size;
total.t_arm += object->resident_page_count;
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}
if (object->shadow_count > 1) {
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/* shared object */
total.t_vmshr += object->size;
total.t_rmshr += object->resident_page_count;
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if (object->flags & OBJ_ACTIVE) {
total.t_avmshr += object->size;
total.t_armshr += object->resident_page_count;
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}
}
}
mtx_unlock(&vm_object_list_mtx);
total.t_free = cnt.v_free_count + cnt.v_cache_count;
return (sysctl_handle_opaque(oidp, &total, sizeof(total), req));
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}
/*
* 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 *)&cnt;
#ifdef SMP
int i;
for (i = 0; i < mp_ncpus; ++i) {
struct pcpu *pcpu = pcpu_find(i);
count += *(int *)((char *)&pcpu->pc_cnt + offset);
}
#else
count += *(int *)((char *)PCPU_PTR(cnt) + offset);
#endif
return (SYSCTL_OUT(req, &count, sizeof(int)));
}
SYSCTL_PROC(_vm, VM_TOTAL, vmtotal, CTLTYPE_OPAQUE|CTLFLAG_RD,
0, sizeof(struct vmtotal), vmtotal, "S,vmtotal",
"System virtual memory statistics");
SYSCTL_NODE(_vm, OID_AUTO, stats, CTLFLAG_RW, 0, "VM meter stats");
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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");
SYSCTL_PROC(_vm_stats_sys, OID_AUTO, v_swtch, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_swtch, 0, vcnt, "IU", "Context switches");
SYSCTL_PROC(_vm_stats_sys, OID_AUTO, v_trap, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_trap, 0, vcnt, "IU", "Traps");
SYSCTL_PROC(_vm_stats_sys, OID_AUTO, v_syscall, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_syscall, 0, vcnt, "IU", "Syscalls");
SYSCTL_PROC(_vm_stats_sys, OID_AUTO, v_intr, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_intr, 0, vcnt, "IU", "Hardware interrupts");
SYSCTL_PROC(_vm_stats_sys, OID_AUTO, v_soft, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_soft, 0, vcnt, "IU", "Software interrupts");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_vm_faults, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_vm_faults, 0, vcnt, "IU", "VM faults");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_cow_faults, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_cow_faults, 0, vcnt, "IU", "COW faults");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_cow_optim, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_cow_optim, 0, vcnt, "IU", "Optimized COW faults");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_zfod, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_zfod, 0, vcnt, "IU", "Zero fill");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_ozfod, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_ozfod, 0, vcnt, "IU", "Optimized zero fill");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_swapin, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_swapin, 0, vcnt, "IU", "Swapin operations");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_swapout, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_swapout, 0, vcnt, "IU", "Swapout operations");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_swappgsin, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_swappgsin, 0, vcnt, "IU", "Swapin pages");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_swappgsout, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_swappgsout, 0, vcnt, "IU", "Swapout pages");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_vnodein, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_vnodein, 0, vcnt, "IU", "Vnodein operations");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_vnodeout, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_vnodeout, 0, vcnt, "IU", "Vnodeout operations");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_vnodepgsin, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_vnodepgsin, 0, vcnt, "IU", "Vnodein pages");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_vnodepgsout, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_vnodepgsout, 0, vcnt, "IU", "Vnodeout pages");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_intrans, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_intrans, 0, vcnt, "IU", "In transit page blocking");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_reactivated, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_reactivated, 0, vcnt, "IU", "Reactivated pages");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_pdwakeups, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_pdwakeups, 0, vcnt, "IU", "Pagedaemon wakeups");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_pdpages, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_pdpages, 0, vcnt, "IU", "Pagedaemon page scans");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_tcached, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_tcached, 0, vcnt, "IU", "Total pages cached");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_dfree, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_dfree, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_pfree, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_pfree, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_tfree, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_tfree, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_page_size, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_page_size, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_page_count, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_page_count, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_free_reserved, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_free_reserved, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_free_target, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_free_target, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_free_min, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_free_min, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_free_count, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_free_count, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_wire_count, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_wire_count, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_active_count, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_active_count, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_inactive_target, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_inactive_target, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_inactive_count, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_inactive_count, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_cache_count, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_cache_count, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_cache_min, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_cache_min, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_cache_max, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_cache_max, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_pageout_free_min, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_pageout_free_min, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_interrupt_free_min, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_interrupt_free_min, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_forks, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_forks, 0, vcnt, "IU", "Number of fork() calls");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_vforks, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_vforks, 0, vcnt, "IU", "Number of vfork() calls");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_rforks, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_rforks, 0, vcnt, "IU", "Number of rfork() calls");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_kthreads, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_kthreads, 0, vcnt, "IU", "Number of fork() calls by kernel");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_forkpages, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_forkpages, 0, vcnt, "IU", "VM pages affected by fork()");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_vforkpages, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_vforkpages, 0, vcnt, "IU", "VM pages affected by vfork()");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_rforkpages, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_rforkpages, 0, vcnt, "IU", "VM pages affected by rfork()");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_kthreadpages, CTLTYPE_UINT|CTLFLAG_RD,
&cnt.v_kthreadpages, 0, vcnt, "IU", "VM pages affected by fork() by kernel");
SYSCTL_INT(_vm_stats_misc, OID_AUTO,
zero_page_count, CTLFLAG_RD, &vm_page_zero_count, 0, "");