From 10754b08736f521a9c5f680bfd89f3f51ee1794a Mon Sep 17 00:00:00 2001
From: kimchy <kimchy@gmail.com>
Date: Fri, 14 May 2010 10:28:18 +0300
Subject: [PATCH] better safeguard for concurrent restart requests

---
 .../cluster/node/restart/TransportNodesRestartAction.java | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/modules/elasticsearch/src/main/java/org/elasticsearch/action/admin/cluster/node/restart/TransportNodesRestartAction.java b/modules/elasticsearch/src/main/java/org/elasticsearch/action/admin/cluster/node/restart/TransportNodesRestartAction.java
index db0a8d1b40d..44915fe605e 100644
--- a/modules/elasticsearch/src/main/java/org/elasticsearch/action/admin/cluster/node/restart/TransportNodesRestartAction.java
+++ b/modules/elasticsearch/src/main/java/org/elasticsearch/action/admin/cluster/node/restart/TransportNodesRestartAction.java
@@ -38,6 +38,7 @@ import org.elasticsearch.util.settings.Settings;
 import java.io.IOException;
 import java.util.List;
 import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.atomic.AtomicReferenceArray;
 
 import static org.elasticsearch.util.TimeValue.*;
@@ -52,7 +53,7 @@ public class TransportNodesRestartAction extends TransportNodesOperationAction<N
 
     private final boolean disabled;
 
-    private volatile boolean restartRequested = false;
+    private AtomicBoolean restartRequested = new AtomicBoolean();
 
     @Inject public TransportNodesRestartAction(Settings settings, ClusterName clusterName, ThreadPool threadPool,
                                                ClusterService clusterService, TransportService transportService,
@@ -101,10 +102,9 @@ public class TransportNodesRestartAction extends TransportNodesOperationAction<N
         if (disabled) {
             throw new ElasticSearchIllegalStateException("Restart is disabled");
         }
-        if (restartRequested) {
+        if (!restartRequested.compareAndSet(false, true)) {
             return new NodesRestartResponse.NodeRestartResponse(clusterService.state().nodes().localNode());
         }
-        restartRequested = true;
         logger.info("Restarting in [{}]", request.delay);
         threadPool.schedule(new Runnable() {
             @Override public void run() {
@@ -127,7 +127,7 @@ public class TransportNodesRestartAction extends TransportNodesOperationAction<N
                     } catch (Exception e) {
                         logger.warn("Failed to restart", e);
                     } finally {
-                        restartRequested = false;
+                        restartRequested.set(false);
                     }
                 }
             }