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Teach vm_page_grab() how to handle the vm object's lock.

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This commit is contained in:
Alan Cox 2003-06-07 23:22:04 +00:00
parent 9ef521ec86
commit 36d1fdf5a2
1 changed files with 16 additions and 4 deletions
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20
sys/vm/vm_page.c
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@ -1443,9 +1443,13 @@ vm_page_t
vm_page_grab(vm_object_t object, vm_pindex_t pindex, int allocflags)
{
vm_page_t m;
int s, generation;
int s, generation, is_object_locked;
GIANT_REQUIRED;
/*
* Remove is_object_locked after vm_object locking is finished.
*/
if (!(is_object_locked = VM_OBJECT_LOCKED(object)))
GIANT_REQUIRED;
retrylookup:
if ((m = vm_page_lookup(object, pindex)) != NULL) {
vm_page_lock_queues();
@ -1456,12 +1460,16 @@ retrylookup:
while ((object->generation == generation) &&
(m->busy || (m->flags & PG_BUSY))) {
vm_page_flag_set(m, PG_WANTED | PG_REFERENCED);
msleep(m, &vm_page_queue_mtx, PVM, "pgrbwt", 0);
if (is_object_locked)
VM_OBJECT_UNLOCK(object);
msleep(m, &vm_page_queue_mtx, PDROP | PVM, "pgrbwt", 0);
if (is_object_locked)
VM_OBJECT_LOCK(object);
if ((allocflags & VM_ALLOC_RETRY) == 0) {
vm_page_unlock_queues();
splx(s);
return NULL;
}
vm_page_lock_queues();
}
vm_page_unlock_queues();
splx(s);
@ -1477,7 +1485,11 @@ retrylookup:
m = vm_page_alloc(object, pindex, allocflags & ~VM_ALLOC_RETRY);
if (m == NULL) {
if (is_object_locked)
VM_OBJECT_UNLOCK(object);
VM_WAIT;
if (is_object_locked)
VM_OBJECT_LOCK(object);
if ((allocflags & VM_ALLOC_RETRY) == 0)
return NULL;
goto retrylookup;