Merge -c 1186554 from trunk to branch-0.23 to complete fix for MAPREDUCE-3188.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-0.23@1186555 13f79535-47bb-0310-9956-ffa450edef68

hadoop-mapreduce-project/CHANGES.txt

@@ -1652,6 +1652,8 @@ Release 0.23.0 - Unreleased
     MAPREDUCE-3179. Ensure failed tests exit with right error code. (Jonathan
     Eagles via acmurthy)
 
+    MAPREDUCE-3188. Ensure correct shutdown in services. (todd via acmurthy) 
+
 Release 0.22.0 - Unreleased
 
   INCOMPATIBLE CHANGES

hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/event/AsyncDispatcher.java

@@ -91,14 +91,16 @@ public class AsyncDispatcher extends AbstractService implements Dispatcher {
   @Override
   public void stop() {
     stopped = true;
-    eventHandlingThread.interrupt();
-    try {
-      eventHandlingThread.join();
-    } catch (InterruptedException ie) {
-      LOG.debug("Interruped Exception while stopping", ie);
+    if (eventHandlingThread != null) {
+      eventHandlingThread.interrupt();
+      try {
+        eventHandlingThread.join();
+      } catch (InterruptedException ie) {
+        LOG.debug("Interrupted Exception while stopping", ie);
+      }
     }
 
-    //stop all the components
+    // stop all the components
     super.stop();
   }
 

hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/service/AbstractService.java

@@ -63,8 +63,12 @@ public abstract class AbstractService implements Service {
 
   @Override
   public synchronized void stop() {
-    if (state == STATE.STOPPED) {
-      return;//already stopped
+    if (state == STATE.STOPPED ||
+        state == STATE.INITED ||
+        state == STATE.NOTINITED) {
+      // already stopped, or else it was never
+      // started (eg another service failing canceled startup)
+      return;
     }
     ensureCurrentState(STATE.STARTED);
     changeState(STATE.STOPPED);

hadoop-mapreduce-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/util/AbstractLivelinessMonitor.java

@@ -50,6 +50,7 @@ public abstract class AbstractLivelinessMonitor<O> extends AbstractService {
 
   @Override
   public void start() {
+    assert !stopped : "starting when already stopped";
     checkerThread = new Thread(new PingChecker());
     checkerThread.setName("Ping Checker");
     checkerThread.start();
@@ -59,7 +60,9 @@ public abstract class AbstractLivelinessMonitor<O> extends AbstractService {
   @Override
   public void stop() {
     stopped = true;
-    checkerThread.interrupt();
+    if (checkerThread != null) {
+      checkerThread.interrupt();
+    }
     super.stop();
   }