Undo part of the scalability commit. Many of the changes

in vm_fault had some performance enhancements not ready
for prime time.  This commit backs out some of the changes.
This commit is contained in:
John Dyson 1996-07-28 01:14:01 +00:00
parent 94a04fd972
commit f230c45cbe
Notes: svn2git 2020-12-20 02:59:44 +00:00
svn path=/head/; revision=17312

View File

@ -66,7 +66,7 @@
* any improvements or extensions that they make and grant Carnegie the
* rights to redistribute these changes.
*
* $Id: vm_fault.c,v 1.53 1996/07/02 02:07:59 dyson Exp $
* $Id: vm_fault.c,v 1.54 1996/07/27 03:23:52 dyson Exp $
*/
/*
@ -293,7 +293,8 @@ RetryFault:;
m->flags |= PG_BUSY;
if (((m->valid & VM_PAGE_BITS_ALL) != VM_PAGE_BITS_ALL) &&
if (m->valid &&
((m->valid & VM_PAGE_BITS_ALL) != VM_PAGE_BITS_ALL) &&
m->object != kernel_object && m->object != kmem_object) {
goto readrest;
}
@ -395,18 +396,20 @@ readrest:
reqpage) : VM_PAGER_FAIL;
if (rv == VM_PAGER_OK) {
/*
* Found the page. Leave it busy while we play
* with it.
*/
/*
* Relookup in case pager changed page. Pager
* is responsible for disposition of old page
* if moved.
*/
if ((m->object != object) || (m->pindex != pindex) ||
(m->flags & PG_TABLED) == 0) {
m = vm_page_lookup(object, pindex);
if( !m) {
UNLOCK_AND_DEALLOCATE;
goto RetryFault;
}
m = vm_page_lookup(object, pindex);
if( !m) {
UNLOCK_AND_DEALLOCATE;
goto RetryFault;
}
hardfault++;
@ -478,26 +481,9 @@ readrest:
}
first_m = NULL;
if ((m->flags & PG_ZERO) == 0) {
if (vm_page_zero_count) {
vm_page_protect(m, VM_PROT_NONE);
PAGE_WAKEUP(m);
vm_page_free(m);
m = vm_page_alloc(object, pindex, VM_ALLOC_ZERO);
if (!m)
panic("vm_fault: missing zero page");
/*
* This should not be true, but just in case...
*/
if ((m->flags & PG_ZERO) == 0) {
vm_page_zero_fill(m);
cnt.v_zfod++;
}
} else {
vm_page_zero_fill(m);
cnt.v_zfod++;
}
}
if ((m->flags & PG_ZERO) == 0)
vm_page_zero_fill(m);
cnt.v_zfod++;
break;
} else {
if (object != first_object) {