From e4a1d491c1982f966c2bfc64edcf0ea692e6521f Mon Sep 17 00:00:00 2001
From: Kelven Yang <kelven@cloud.com>
Date: Fri, 5 Aug 2011 14:06:34 -0700
Subject: [PATCH] bug 10976: NPE fix to avoid blocking shutdown process

---
 utils/src/com/cloud/utils/db/GlobalLock.java | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/utils/src/com/cloud/utils/db/GlobalLock.java b/utils/src/com/cloud/utils/db/GlobalLock.java
index c87106ef80d..067ad57de30 100644
--- a/utils/src/com/cloud/utils/db/GlobalLock.java
+++ b/utils/src/com/cloud/utils/db/GlobalLock.java
@@ -103,10 +103,12 @@ public class GlobalLock {
 	private static void releaseInternLock(String name) {
 		synchronized(s_lockMap) {
 			GlobalLock lock = s_lockMap.get(name);
-			assert(lock != null);
-			
-			if(lock.referenceCount == 0)
-				s_lockMap.remove(name);
+			if(lock != null) {
+				if(lock.referenceCount == 0)
+					s_lockMap.remove(name);
+			} else {
+				s_logger.warn("Releasing " + name + ", but it is already released.");
+			}
 		}
 	}