svn commit: r209861 - in head/sys: kern vm
Alan Cox
alc at FreeBSD.org
Fri Jul 9 19:38:30 UTC 2010
Author: alc
Date: Fri Jul 9 19:38:30 2010
New Revision: 209861
URL: http://svn.freebsd.org/changeset/base/209861
Log:
Add support for the VM_ALLOC_COUNT() hint to vm_page_alloc(). Consequently,
the maintenance of vm_pageout_deficit can be localized to just two places:
vm_page_alloc() and vm_pageout_scan().
This change also corrects an off-by-one error in the maintenance of
vm_pageout_deficit. Historically, the buffer cache functions, allocbuf()
and vm_hold_load_pages(), have not taken into account that vm_page_alloc()
already increments vm_pageout_deficit by one.
Reviewed by: kib
Modified:
head/sys/kern/vfs_bio.c
head/sys/vm/vm_page.c
head/sys/vm/vm_page.h
Modified: head/sys/kern/vfs_bio.c
==============================================================================
--- head/sys/kern/vfs_bio.c Fri Jul 9 17:38:15 2010 (r209860)
+++ head/sys/kern/vfs_bio.c Fri Jul 9 19:38:30 2010 (r209861)
@@ -3752,10 +3752,9 @@ tryagain:
* process we are.
*/
p = vm_page_alloc(NULL, pg >> PAGE_SHIFT, VM_ALLOC_NOOBJ |
- VM_ALLOC_SYSTEM | VM_ALLOC_WIRED);
+ VM_ALLOC_SYSTEM | VM_ALLOC_WIRED |
+ VM_ALLOC_COUNT((to - pg) >> PAGE_SHIFT));
if (!p) {
- atomic_add_int(&vm_pageout_deficit,
- (to - pg) >> PAGE_SHIFT);
VM_WAIT;
goto tryagain;
}
Modified: head/sys/vm/vm_page.c
==============================================================================
--- head/sys/vm/vm_page.c Fri Jul 9 17:38:15 2010 (r209860)
+++ head/sys/vm/vm_page.c Fri Jul 9 19:38:30 2010 (r209861)
@@ -1264,7 +1264,8 @@ vm_page_alloc(vm_object_t object, vm_pin
* Not allocatable, give up.
*/
mtx_unlock(&vm_page_queue_free_mtx);
- atomic_add_int(&vm_pageout_deficit, 1);
+ atomic_add_int(&vm_pageout_deficit,
+ MAX((u_int)req >> VM_ALLOC_COUNT_SHIFT, 1));
pagedaemon_wakeup();
return (NULL);
}
@@ -2041,7 +2042,6 @@ vm_page_t
vm_page_grab(vm_object_t object, vm_pindex_t pindex, int allocflags)
{
vm_page_t m;
- u_int count;
VM_OBJECT_LOCK_ASSERT(object, MA_OWNED);
KASSERT((allocflags & VM_ALLOC_RETRY) != 0,
@@ -2071,12 +2071,9 @@ retrylookup:
}
}
m = vm_page_alloc(object, pindex, allocflags & ~(VM_ALLOC_RETRY |
- VM_ALLOC_IGN_SBUSY | VM_ALLOC_COUNT_MASK));
+ VM_ALLOC_IGN_SBUSY));
if (m == NULL) {
VM_OBJECT_UNLOCK(object);
- count = (u_int)allocflags >> VM_ALLOC_COUNT_SHIFT;
- if (count > 0)
- atomic_add_int(&vm_pageout_deficit, count);
VM_WAIT;
VM_OBJECT_LOCK(object);
goto retrylookup;
Modified: head/sys/vm/vm_page.h
==============================================================================
--- head/sys/vm/vm_page.h Fri Jul 9 17:38:15 2010 (r209860)
+++ head/sys/vm/vm_page.h Fri Jul 9 19:38:30 2010 (r209861)
@@ -321,7 +321,6 @@ extern struct vpglocks vm_page_queue_loc
#define VM_ALLOC_COUNT_SHIFT 16
#define VM_ALLOC_COUNT(count) ((count) << VM_ALLOC_COUNT_SHIFT)
-#define VM_ALLOC_COUNT_MASK VM_ALLOC_COUNT(0xffff)
void vm_page_flag_set(vm_page_t m, unsigned short bits);
void vm_page_flag_clear(vm_page_t m, unsigned short bits);
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