- Convert vm_object_pip_wait() from using tsleep() to msleep().

 - Make vm_object_pip_sleep() static.
 - Lock the vm_object when performing vm_object_pip_wait().

4 files changed, 22 insertions, 9 deletions

diff --git a/sys/vm/swap_pager.c b/sys/vm/swap_pager.c
index 4cff663..d68a465 100644
--- a/sys/vm/swap_pager.c
+++ b/sys/vm/swap_pager.c
@@ -428,7 +428,9 @@ swap_pager_dealloc(object)
 	}
 	mtx_unlock(&sw_alloc_mtx);
 
+	VM_OBJECT_LOCK(object);
 	vm_object_pip_wait(object, "swpdea");
+	VM_OBJECT_UNLOCK(object);
 
 	/*
 	 * Free all remaining metadata.  We only bother to free it from 
@@ -1775,7 +1777,9 @@ restart:
 	     * We wait on an arbitrary object to clock our rescans
 	     * to the rate of paging completion.
 	     */
+	    VM_OBJECT_LOCK(waitobj);
 	    vm_object_pip_wait(waitobj, "swpoff");
+	    VM_OBJECT_UNLOCK(waitobj);
 	    goto full_rescan;
 	}
 	if (*sw_used)
diff --git a/sys/vm/vm_object.c b/sys/vm/vm_object.c
index 7aa399a..944d033 100644
--- a/sys/vm/vm_object.c
+++ b/sys/vm/vm_object.c
@@ -109,6 +109,7 @@ SYSCTL_INT(_vm, OID_AUTO, msync_flush_flags,
 
 static void	vm_object_qcollapse(vm_object_t object);
 static int	vm_object_page_collect_flush(vm_object_t object, vm_page_t p, int curgeneration, int pagerflags);
+static void	vm_object_pip_sleep(vm_object_t object, char *waitid);
 
 /*
  *	Virtual memory objects maintain the actual data
@@ -306,7 +307,7 @@ vm_object_pip_wakeupn(vm_object_t object, short i)
 	}
 }
 
-void
+static void
 vm_object_pip_sleep(vm_object_t object, char *waitid)
 {
 	GIANT_REQUIRED;
@@ -323,9 +324,12 @@ vm_object_pip_sleep(vm_object_t object, char *waitid)
 void
 vm_object_pip_wait(vm_object_t object, char *waitid)
 {
-	GIANT_REQUIRED;
-	while (object->paging_in_progress)
-		vm_object_pip_sleep(object, waitid);
+
+	VM_OBJECT_LOCK_ASSERT(object, MA_OWNED);
+	while (object->paging_in_progress) {
+		object->flags |= OBJ_PIPWNT;
+		msleep(object, VM_OBJECT_MTX(object), PVM, waitid, 0);
+	}
 }
 
 /*
@@ -537,12 +541,12 @@ vm_object_terminate(vm_object_t object)
 	 */
 	VM_OBJECT_LOCK(object);
 	vm_object_set_flag(object, OBJ_DEAD);
-	VM_OBJECT_UNLOCK(object);
 
 	/*
 	 * wait for the pageout daemon to be done with the object
 	 */
 	vm_object_pip_wait(object, "objtrm");
+	VM_OBJECT_UNLOCK(object);
 
 	KASSERT(!object->paging_in_progress,
 		("vm_object_terminate: pageout in progress"));
diff --git a/sys/vm/vm_object.h b/sys/vm/vm_object.h
index f4890bc..b7090c3 100644
--- a/sys/vm/vm_object.h
+++ b/sys/vm/vm_object.h
@@ -174,6 +174,7 @@ extern vm_object_t kmem_object;
 #define	VM_OBJECT_LOCK_ASSERT(object, type) \
 					mtx_assert(&(object)->mtx, (type))
 #define	VM_OBJECT_LOCKED(object)	mtx_owned(&(object)->mtx)
+#define	VM_OBJECT_MTX(object)		(&(object)->mtx)
 #define	VM_OBJECT_UNLOCK(object)	mtx_unlock(&(object)->mtx)
 
 #define	vm_object_lock(object) \
@@ -187,7 +188,6 @@ void vm_object_pip_add(vm_object_t object, short i);
 void vm_object_pip_subtract(vm_object_t object, short i);
 void vm_object_pip_wakeup(vm_object_t object);
 void vm_object_pip_wakeupn(vm_object_t object, short i);
-void vm_object_pip_sleep(vm_object_t object, char *waitid);
 void vm_object_pip_wait(vm_object_t object, char *waitid);
 
 vm_object_t vm_object_allocate (objtype_t, vm_pindex_t);
diff --git a/sys/vm/vnode_pager.c b/sys/vm/vnode_pager.c
index 0be23ef..8115908 100644
--- a/sys/vm/vnode_pager.c
+++ b/sys/vm/vnode_pager.c
@@ -139,9 +139,11 @@ vnode_pager_alloc(void *handle, vm_ooffset_t size, vm_prot_t prot,
 	 * If the object is being terminated, wait for it to
 	 * go away.
 	 */
-	while (((object = vp->v_object) != NULL) &&
-		(object->flags & OBJ_DEAD)) {
-		tsleep(object, PVM, "vadead", 0);
+	while ((object = vp->v_object) != NULL) {
+		VM_OBJECT_LOCK(object);
+		if ((object->flags & OBJ_DEAD) == 0)
+			break;
+		msleep(object, VM_OBJECT_MTX(object), PDROP | PVM, "vadead", 0);
 	}
 
 	if (vp->v_usecount == 0)
@@ -159,6 +161,7 @@ vnode_pager_alloc(void *handle, vm_ooffset_t size, vm_prot_t prot,
 		vp->v_object = object;
 	} else {
 		object->ref_count++;
+		VM_OBJECT_UNLOCK(object);
 	}
 	VI_LOCK(vp);
 	vp->v_usecount++;
@@ -182,7 +185,9 @@ vnode_pager_dealloc(object)
 	if (vp == NULL)
 		panic("vnode_pager_dealloc: pager already dealloced");
 
+	VM_OBJECT_LOCK(object);
 	vm_object_pip_wait(object, "vnpdea");
+	VM_OBJECT_UNLOCK(object);
 
 	object->handle = NULL;
 	object->type = OBJT_DEAD;