freebsd-skq/sys/vm/vm_meter.c
jhb c7ac62aecd Fix some locking nits with the p_state field of struct proc:
- Hold the proc lock while changing the state from PRS_NEW to PRS_NORMAL
  in fork to honor the locking requirements.  While here, expand the scope
  of the PROC_LOCK() on the new process (p2) to avoid some LORs.  Previously
  the code was locking the new child process (p2) after it had locked the
  parent process (p1).  However, when locking two processes, the safe order
  is to lock the child first, then the parent.
- Fix various places that were checking p_state against PRS_NEW without
  having the process locked to use PROC_LOCK().  Every place was already
  locking the process, just after the PRS_NEW check.
- Remove or reduce the use of PROC_SLOCK() for places that were checking
  p_state against PRS_NEW.  The PROC_LOCK() alone is sufficient for reading
  the current state.
- Reorder fill_kinfo_proc() slightly so it only acquires PROC_SLOCK() once.

MFC after:	1 week
2011-03-24 18:40:11 +00:00

374 lines
14 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/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 cnt;
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 |
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) {
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);
/*
* 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_LOCK(object);
vm_object_set_flag(object, OBJ_ACTIVE);
paging |= object->paging_in_progress;
VM_OBJECT_UNLOCK(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 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 || object->type == OBJT_SG) {
/*
* 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 = cnt.v_free_count + 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 *)&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");
SYSCTL_PROC(_vm_stats_sys, OID_AUTO, v_swtch, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_swtch, 0, vcnt, "IU", "Context switches");
SYSCTL_PROC(_vm_stats_sys, OID_AUTO, v_trap, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_trap, 0, vcnt, "IU", "Traps");
SYSCTL_PROC(_vm_stats_sys, OID_AUTO, v_syscall, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_syscall, 0, vcnt, "IU", "Syscalls");
SYSCTL_PROC(_vm_stats_sys, OID_AUTO, v_intr, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_intr, 0, vcnt, "IU", "Hardware interrupts");
SYSCTL_PROC(_vm_stats_sys, OID_AUTO, v_soft, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_soft, 0, vcnt, "IU", "Software interrupts");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_vm_faults, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_vm_faults, 0, vcnt, "IU", "VM faults");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_cow_faults, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_cow_faults, 0, vcnt, "IU", "COW faults");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_cow_optim, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_cow_optim, 0, vcnt, "IU", "Optimized COW faults");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_zfod, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_zfod, 0, vcnt, "IU", "Zero fill");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_ozfod, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_ozfod, 0, vcnt, "IU", "Optimized zero fill");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_swapin, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_swapin, 0, vcnt, "IU", "Swapin operations");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_swapout, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_swapout, 0, vcnt, "IU", "Swapout operations");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_swappgsin, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_swappgsin, 0, vcnt, "IU", "Swapin pages");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_swappgsout, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_swappgsout, 0, vcnt, "IU", "Swapout pages");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_vnodein, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_vnodein, 0, vcnt, "IU", "Vnodein operations");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_vnodeout, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_vnodeout, 0, vcnt, "IU", "Vnodeout operations");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_vnodepgsin, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_vnodepgsin, 0, vcnt, "IU", "Vnodein pages");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_vnodepgsout, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_vnodepgsout, 0, vcnt, "IU", "Vnodeout pages");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_intrans, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_intrans, 0, vcnt, "IU", "In transit page blocking");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_reactivated, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_reactivated, 0, vcnt, "IU", "Reactivated pages");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_pdwakeups, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_pdwakeups, 0, vcnt, "IU", "Pagedaemon wakeups");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_pdpages, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_pdpages, 0, vcnt, "IU", "Pagedaemon page scans");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_tcached, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_tcached, 0, vcnt, "IU", "Total pages cached");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_dfree, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_dfree, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_pfree, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_pfree, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_tfree, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_tfree, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_page_size, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_page_size, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_page_count, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_page_count, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_free_reserved, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_free_reserved, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_free_target, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_free_target, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_free_min, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_free_min, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_free_count, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_free_count, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_wire_count, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_wire_count, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_active_count, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_active_count, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_inactive_target, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_inactive_target, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_inactive_count, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_inactive_count, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_cache_count, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_cache_count, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_cache_min, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_cache_min, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_cache_max, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_cache_max, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_pageout_free_min, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_pageout_free_min, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_interrupt_free_min, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_interrupt_free_min, 0, vcnt, "IU", "");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_forks, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_forks, 0, vcnt, "IU", "Number of fork() calls");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_vforks, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_vforks, 0, vcnt, "IU", "Number of vfork() calls");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_rforks, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_rforks, 0, vcnt, "IU", "Number of rfork() calls");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_kthreads, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&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|CTLFLAG_MPSAFE,
&cnt.v_forkpages, 0, vcnt, "IU", "VM pages affected by fork()");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_vforkpages, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_vforkpages, 0, vcnt, "IU", "VM pages affected by vfork()");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_rforkpages, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&cnt.v_rforkpages, 0, vcnt, "IU", "VM pages affected by rfork()");
SYSCTL_PROC(_vm_stats_vm, OID_AUTO, v_kthreadpages, CTLTYPE_UINT|CTLFLAG_RD|CTLFLAG_MPSAFE,
&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, "");