NetBSD/sys/uvm/uvm_page_i.h
thorpej 1779f8f71b Page scanner improvements, behavior is actually a bit more like
Mach VM's now.  Specific changes:
- Pages now need not have all of their mappings removed before being
  put on the inactive list.  They only need to have the "referenced"
  attribute cleared.  This makes putting pages onto the inactive list
  much more efficient.  In order to eliminate redundant clearings of
  "refrenced", callers of uvm_pagedeactivate() must now do this
  themselves.
- When checking the "modified" attribute for a page (for clearing
  PG_CLEAN), make sure to only do it if PG_CLEAN is currently set on
  the page (saves a potentially expensive pmap operation).
- When scanning the inactive list, if a page is referenced, reactivate
  it (this part was actually added in uvm_pdaemon.c,v 1.27).  This
  now works properly now that pages on the inactive list are allowed to
  have mappings.
- When scanning the inactive list and considering a page for freeing,
  remove all mappings, and then check the "modified" attribute if the
  page is marked PG_CLEAN.
- When scanning the active list, if the page was referenced since its
  last sweep by the scanner, don't deactivate it.  (This part was
  actually added in uvm_pdaemon.c,v 1.28.)

These changes greatly improve interactive performance during
moderate to high memory and I/O load.
2001-01-28 23:30:42 +00:00

320 lines
8.1 KiB
C

/* $NetBSD: uvm_page_i.h,v 1.16 2001/01/28 23:30:45 thorpej Exp $ */
/*
* Copyright (c) 1997 Charles D. Cranor and Washington University.
* Copyright (c) 1991, 1993, The Regents of the University of California.
*
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* The Mach Operating System project at Carnegie-Mellon University.
*
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Charles D. Cranor,
* Washington University, the University of California, Berkeley and
* its contributors.
* 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_page.c 8.3 (Berkeley) 3/21/94
* from: Id: uvm_page_i.h,v 1.1.2.7 1998/01/05 00:26:02 chuck Exp
*
*
* Copyright (c) 1987, 1990 Carnegie-Mellon University.
* All rights reserved.
*
* Permission to use, copy, modify and distribute this software and
* its documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
* FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie the
* rights to redistribute these changes.
*/
#ifndef _UVM_UVM_PAGE_I_H_
#define _UVM_UVM_PAGE_I_H_
/*
* uvm_page_i.h
*/
/*
* inline functions [maybe]
*/
#if defined(UVM_PAGE_INLINE) || defined(UVM_PAGE)
/*
* uvm_lock_fpageq: lock the free page queue
*
* => free page queue can be accessed in interrupt context, so this
* blocks all interrupts that can cause memory allocation, and
* returns the previous interrupt level.
*/
PAGE_INLINE int
uvm_lock_fpageq()
{
int s;
s = splvm();
simple_lock(&uvm.fpageqlock);
return (s);
}
/*
* uvm_unlock_fpageq: unlock the free page queue
*
* => caller must supply interrupt level returned by uvm_lock_fpageq()
* so that it may be restored.
*/
PAGE_INLINE void
uvm_unlock_fpageq(s)
int s;
{
simple_unlock(&uvm.fpageqlock);
splx(s);
}
/*
* uvm_pagelookup: look up a page
*
* => caller should lock object to keep someone from pulling the page
* out from under it
*/
struct vm_page *
uvm_pagelookup(obj, off)
struct uvm_object *obj;
voff_t off;
{
struct vm_page *pg;
struct pglist *buck;
int s;
buck = &uvm.page_hash[uvm_pagehash(obj,off)];
s = splvm();
simple_lock(&uvm.hashlock);
TAILQ_FOREACH(pg, buck, hashq) {
if (pg->uobject == obj && pg->offset == off) {
break;
}
}
simple_unlock(&uvm.hashlock);
splx(s);
return(pg);
}
/*
* uvm_pagewire: wire the page, thus removing it from the daemon's grasp
*
* => caller must lock page queues
*/
PAGE_INLINE void
uvm_pagewire(pg)
struct vm_page *pg;
{
if (pg->wire_count == 0) {
if (pg->pqflags & PQ_ACTIVE) {
TAILQ_REMOVE(&uvm.page_active, pg, pageq);
pg->pqflags &= ~PQ_ACTIVE;
uvmexp.active--;
}
if (pg->pqflags & PQ_INACTIVE) {
if (pg->pqflags & PQ_SWAPBACKED)
TAILQ_REMOVE(&uvm.page_inactive_swp, pg, pageq);
else
TAILQ_REMOVE(&uvm.page_inactive_obj, pg, pageq);
pg->pqflags &= ~PQ_INACTIVE;
uvmexp.inactive--;
}
uvmexp.wired++;
}
pg->wire_count++;
}
/*
* uvm_pageunwire: unwire the page.
*
* => activate if wire count goes to zero.
* => caller must lock page queues
*/
PAGE_INLINE void
uvm_pageunwire(pg)
struct vm_page *pg;
{
pg->wire_count--;
if (pg->wire_count == 0) {
TAILQ_INSERT_TAIL(&uvm.page_active, pg, pageq);
uvmexp.active++;
pg->pqflags |= PQ_ACTIVE;
uvmexp.wired--;
}
}
/*
* uvm_pagedeactivate: deactivate page
*
* => caller must lock page queues
* => caller must check to make sure page is not wired
* => object that page belongs to must be locked (so we can adjust pg->flags)
* => caller must clear the reference on the page before calling
*/
PAGE_INLINE void
uvm_pagedeactivate(pg)
struct vm_page *pg;
{
if (pg->pqflags & PQ_ACTIVE) {
TAILQ_REMOVE(&uvm.page_active, pg, pageq);
pg->pqflags &= ~PQ_ACTIVE;
uvmexp.active--;
}
if ((pg->pqflags & PQ_INACTIVE) == 0) {
KASSERT(pg->wire_count == 0);
if (pg->pqflags & PQ_SWAPBACKED)
TAILQ_INSERT_TAIL(&uvm.page_inactive_swp, pg, pageq);
else
TAILQ_INSERT_TAIL(&uvm.page_inactive_obj, pg, pageq);
pg->pqflags |= PQ_INACTIVE;
uvmexp.inactive++;
/*
* update the "clean" bit. this isn't 100%
* accurate, and doesn't have to be. we'll
* re-sync it after we zap all mappings when
* scanning the inactive list.
*/
if ((pg->flags & PG_CLEAN) != 0 &&
pmap_is_modified(pg))
pg->flags &= ~PG_CLEAN;
}
}
/*
* uvm_pageactivate: activate page
*
* => caller must lock page queues
*/
PAGE_INLINE void
uvm_pageactivate(pg)
struct vm_page *pg;
{
if (pg->pqflags & PQ_INACTIVE) {
if (pg->pqflags & PQ_SWAPBACKED)
TAILQ_REMOVE(&uvm.page_inactive_swp, pg, pageq);
else
TAILQ_REMOVE(&uvm.page_inactive_obj, pg, pageq);
pg->pqflags &= ~PQ_INACTIVE;
uvmexp.inactive--;
}
if (pg->wire_count == 0) {
/*
* if page is already active, remove it from list so we
* can put it at tail. if it wasn't active, then mark
* it active and bump active count
*/
if (pg->pqflags & PQ_ACTIVE)
TAILQ_REMOVE(&uvm.page_active, pg, pageq);
else {
pg->pqflags |= PQ_ACTIVE;
uvmexp.active++;
}
TAILQ_INSERT_TAIL(&uvm.page_active, pg, pageq);
}
}
/*
* uvm_pagezero: zero fill a page
*
* => if page is part of an object then the object should be locked
* to protect pg->flags.
*/
PAGE_INLINE void
uvm_pagezero(pg)
struct vm_page *pg;
{
pg->flags &= ~PG_CLEAN;
pmap_zero_page(VM_PAGE_TO_PHYS(pg));
}
/*
* uvm_pagecopy: copy a page
*
* => if page is part of an object then the object should be locked
* to protect pg->flags.
*/
PAGE_INLINE void
uvm_pagecopy(src, dst)
struct vm_page *src, *dst;
{
dst->flags &= ~PG_CLEAN;
pmap_copy_page(VM_PAGE_TO_PHYS(src), VM_PAGE_TO_PHYS(dst));
}
/*
* uvm_page_lookup_freelist: look up the free list for the specified page
*/
PAGE_INLINE int
uvm_page_lookup_freelist(pg)
struct vm_page *pg;
{
int lcv;
lcv = vm_physseg_find(atop(VM_PAGE_TO_PHYS(pg)), NULL);
KASSERT(lcv != -1);
return (vm_physmem[lcv].free_list);
}
#endif /* defined(UVM_PAGE_INLINE) || defined(UVM_PAGE) */
#endif /* _UVM_UVM_PAGE_I_H_ */