mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-17 10:26:15 +00:00
29bcc4514f
SW_INVOL. Assert that one of these is set in mi_switch() and propery adjust the rusage statistics. This is to simplify the large number of users of this interface which were previously all required to adjust the proper counter prior to calling mi_switch(). This also facilitates more switch and locking optimizations. - Change all callers of mi_switch() to pass the appropriate paramter and remove direct references to the process statistics.
176 lines
4.9 KiB
C
176 lines
4.9 KiB
C
/*-
|
|
* Copyright (c) 1994 John Dyson
|
|
* Copyright (c) 2001 Matt Dillon
|
|
*
|
|
* 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 AUTHOR ``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 AUTHOR 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.
|
|
*
|
|
* from: @(#)vm_machdep.c 7.3 (Berkeley) 5/13/91
|
|
* Utah $Hdr: vm_machdep.c 1.16.1.1 89/06/23$
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/kernel.h>
|
|
#include <sys/proc.h>
|
|
#include <sys/resourcevar.h>
|
|
#include <sys/vmmeter.h>
|
|
#include <sys/lock.h>
|
|
#include <sys/mutex.h>
|
|
#include <sys/sched.h>
|
|
#include <sys/sysctl.h>
|
|
#include <sys/kthread.h>
|
|
|
|
#include <vm/vm.h>
|
|
#include <vm/vm_page.h>
|
|
|
|
SYSCTL_DECL(_vm_stats_misc);
|
|
|
|
static int cnt_prezero;
|
|
SYSCTL_INT(_vm_stats_misc, OID_AUTO,
|
|
cnt_prezero, CTLFLAG_RD, &cnt_prezero, 0, "");
|
|
|
|
static int idlezero_enable = 1;
|
|
SYSCTL_INT(_vm, OID_AUTO, idlezero_enable, CTLFLAG_RW, &idlezero_enable, 0, "");
|
|
TUNABLE_INT("vm.idlezero_enable", &idlezero_enable);
|
|
|
|
static int idlezero_maxrun = 16;
|
|
SYSCTL_INT(_vm, OID_AUTO, idlezero_maxrun, CTLFLAG_RW, &idlezero_maxrun, 0, "");
|
|
TUNABLE_INT("vm.idlezero_maxrun", &idlezero_maxrun);
|
|
|
|
/*
|
|
* Implement the pre-zeroed page mechanism.
|
|
*/
|
|
|
|
#define ZIDLE_LO(v) ((v) * 2 / 3)
|
|
#define ZIDLE_HI(v) ((v) * 4 / 5)
|
|
|
|
static int zero_state;
|
|
|
|
static int
|
|
vm_page_zero_check(void)
|
|
{
|
|
|
|
if (!idlezero_enable)
|
|
return 0;
|
|
/*
|
|
* Attempt to maintain approximately 1/2 of our free pages in a
|
|
* PG_ZERO'd state. Add some hysteresis to (attempt to) avoid
|
|
* generally zeroing a page when the system is near steady-state.
|
|
* Otherwise we might get 'flutter' during disk I/O / IPC or
|
|
* fast sleeps. We also do not want to be continuously zeroing
|
|
* pages because doing so may flush our L1 and L2 caches too much.
|
|
*/
|
|
if (zero_state && vm_page_zero_count >= ZIDLE_LO(cnt.v_free_count))
|
|
return 0;
|
|
if (vm_page_zero_count >= ZIDLE_HI(cnt.v_free_count))
|
|
return 0;
|
|
return 1;
|
|
}
|
|
|
|
static int
|
|
vm_page_zero_idle(void)
|
|
{
|
|
static int free_rover;
|
|
vm_page_t m;
|
|
|
|
mtx_lock_spin(&vm_page_queue_free_mtx);
|
|
zero_state = 0;
|
|
m = vm_pageq_find(PQ_FREE, free_rover, FALSE);
|
|
if (m != NULL && (m->flags & PG_ZERO) == 0) {
|
|
vm_pageq_remove_nowakeup(m);
|
|
mtx_unlock_spin(&vm_page_queue_free_mtx);
|
|
pmap_zero_page_idle(m);
|
|
mtx_lock_spin(&vm_page_queue_free_mtx);
|
|
m->flags |= PG_ZERO;
|
|
vm_pageq_enqueue(PQ_FREE + m->pc, m);
|
|
++vm_page_zero_count;
|
|
++cnt_prezero;
|
|
if (vm_page_zero_count >= ZIDLE_HI(cnt.v_free_count))
|
|
zero_state = 1;
|
|
}
|
|
free_rover = (free_rover + PQ_PRIME2) & PQ_L2_MASK;
|
|
mtx_unlock_spin(&vm_page_queue_free_mtx);
|
|
return 1;
|
|
}
|
|
|
|
|
|
/* Called by vm_page_free to hint that a new page is available */
|
|
void
|
|
vm_page_zero_idle_wakeup(void)
|
|
{
|
|
|
|
if (idlezero_enable && vm_page_zero_check())
|
|
wakeup(&zero_state);
|
|
}
|
|
|
|
static void
|
|
vm_pagezero(void)
|
|
{
|
|
struct thread *td;
|
|
struct proc *p;
|
|
struct rtprio rtp;
|
|
int pages = 0;
|
|
int pri;
|
|
|
|
td = curthread;
|
|
p = td->td_proc;
|
|
rtp.prio = RTP_PRIO_MAX;
|
|
rtp.type = RTP_PRIO_IDLE;
|
|
mtx_lock_spin(&sched_lock);
|
|
rtp_to_pri(&rtp, td->td_ksegrp);
|
|
pri = td->td_priority;
|
|
mtx_unlock_spin(&sched_lock);
|
|
PROC_LOCK(p);
|
|
p->p_flag |= P_NOLOAD;
|
|
PROC_UNLOCK(p);
|
|
|
|
for (;;) {
|
|
if (vm_page_zero_check()) {
|
|
pages += vm_page_zero_idle();
|
|
if (pages > idlezero_maxrun || sched_runnable()) {
|
|
mtx_lock_spin(&sched_lock);
|
|
mi_switch(SW_VOL);
|
|
mtx_unlock_spin(&sched_lock);
|
|
pages = 0;
|
|
}
|
|
} else {
|
|
tsleep(&zero_state, pri, "pgzero", hz * 300);
|
|
pages = 0;
|
|
}
|
|
}
|
|
}
|
|
|
|
static struct proc *pagezero_proc;
|
|
static struct kproc_desc pagezero_kp = {
|
|
"pagezero",
|
|
vm_pagezero,
|
|
&pagezero_proc
|
|
};
|
|
SYSINIT(pagezero, SI_SUB_KTHREAD_VM, SI_ORDER_ANY, kproc_start, &pagezero_kp)
|