From db27dcc0f0f5d432e8de03d726b02faae305d7c8 Mon Sep 17 00:00:00 2001
From: Tor Egge <tegge@FreeBSD.org>
Date: Fri, 17 Feb 2006 18:22:19 +0000
Subject: [PATCH] Check return value from nonblocking call to vn_start_write().

---
 sys/vm/vm_pageout.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/sys/vm/vm_pageout.c b/sys/vm/vm_pageout.c
index f5efd9ff3c9..b5abcebab38 100644
--- a/sys/vm/vm_pageout.c
+++ b/sys/vm/vm_pageout.c
@@ -931,8 +931,14 @@ rescan0:
 			if (object->type == OBJT_VNODE) {
 				vp = object->handle;
 				mp = NULL;
-				if (vp->v_type == VREG)
-					vn_start_write(vp, &mp, V_NOWAIT);
+				if (vp->v_type == VREG &&
+				    vn_start_write(vp, &mp, V_NOWAIT) != 0) {
+					++pageout_lock_miss;
+					if (object->flags & OBJ_MIGHTBEDIRTY)
+						vnodes_skipped++;
+					VM_OBJECT_UNLOCK(object);
+					continue;
+				}
 				vm_page_unlock_queues();
 				VI_LOCK(vp);
 				VM_OBJECT_UNLOCK(object);