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Don't acquire Giant in vm_object_deallocate() unless the object is vnode-

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backed.
This commit is contained in:
alc 2004-01-18 03:44:14 +00:00
parent 224beac0d6
commit 12eb36a03f
1 changed files with 12 additions and 8 deletions
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20
sys/vm/vm_object.c
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@ -446,13 +446,20 @@ vm_object_deallocate(vm_object_t object)
{ {
vm_object_t temp; vm_object_t temp;
if (object != kmem_object)
mtx_lock(&Giant);
while (object != NULL) { while (object != NULL) {
/*
* In general, the object should be locked when working with
* its type. In this case, in order to maintain proper lock
* ordering, an exception is possible because a vnode-backed
* object never changes its type.
*/
if (object->type == OBJT_VNODE)
mtx_lock(&Giant);
VM_OBJECT_LOCK(object); VM_OBJECT_LOCK(object);
if (object->type == OBJT_VNODE) { if (object->type == OBJT_VNODE) {
vm_object_vndeallocate(object); vm_object_vndeallocate(object);
goto done; mtx_unlock(&Giant);
return;
} }
KASSERT(object->ref_count != 0, KASSERT(object->ref_count != 0,
@ -467,7 +474,7 @@ vm_object_deallocate(vm_object_t object)
object->ref_count--; object->ref_count--;
if (object->ref_count > 1) { if (object->ref_count > 1) {
VM_OBJECT_UNLOCK(object); VM_OBJECT_UNLOCK(object);
goto done; return;
} else if (object->ref_count == 1) { } else if (object->ref_count == 1) {
if (object->shadow_count == 0) { if (object->shadow_count == 0) {
vm_object_set_flag(object, OBJ_ONEMAPPING); vm_object_set_flag(object, OBJ_ONEMAPPING);
@ -526,7 +533,7 @@ vm_object_deallocate(vm_object_t object)
VM_OBJECT_UNLOCK(robject); VM_OBJECT_UNLOCK(robject);
} }
VM_OBJECT_UNLOCK(object); VM_OBJECT_UNLOCK(object);
goto done; return;
} }
doterm: doterm:
temp = object->backing_object; temp = object->backing_object;
@ -549,9 +556,6 @@ vm_object_deallocate(vm_object_t object)
VM_OBJECT_UNLOCK(object); VM_OBJECT_UNLOCK(object);
object = temp; object = temp;
} }
done:
if (object != kmem_object)
mtx_unlock(&Giant);
} }
/* /*