YARN-9096: Some GpuResourcePlugin and ResourcePluginManager methods are synchronized unnecessarily. Contributed by Gergely Pollak

(cherry picked from commit 742e30b47381ad63e2b2fe63738cd0fe6cbce106)

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-nodemanager/src/main/java/org/apache/hadoop/yarn/server/nodemanager/containermanager/resourceplugin/ResourcePluginManager.java

@@ -52,7 +52,7 @@ public class ResourcePluginManager {
   private Map<String, ResourcePlugin> configuredPlugins =
           Collections.emptyMap();
 
-  public synchronized void initialize(Context context)
+  public void initialize(Context context)
       throws YarnException {
     Configuration conf = context.getConf();
 
@@ -108,7 +108,7 @@ public class ResourcePluginManager {
     }
   }
 
-  public synchronized void cleanup() throws YarnException {
+  public void cleanup() throws YarnException {
     for (ResourcePlugin plugin : configuredPlugins.values()) {
       plugin.cleanup();
     }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-nodemanager/src/main/java/org/apache/hadoop/yarn/server/nodemanager/containermanager/resourceplugin/gpu/GpuResourcePlugin.java

@@ -54,7 +54,7 @@ public class GpuResourcePlugin implements ResourcePlugin {
   }
 
   @Override
-  public synchronized void initialize(Context context) throws YarnException {
+  public void initialize(Context context) throws YarnException {
     this.gpuDiscoverer.initialize(context.getConf());
     this.dockerCommandPlugin =
         GpuDockerCommandPluginFactory.createGpuDockerCommandPlugin(
@@ -62,7 +62,7 @@ public class GpuResourcePlugin implements ResourcePlugin {
   }
 
   @Override
-  public synchronized ResourceHandler createResourceHandler(
+  public ResourceHandler createResourceHandler(
       Context context, CGroupsHandler cGroupsHandler,
       PrivilegedOperationExecutor privilegedOperationExecutor) {
     if (gpuResourceHandler == null) {
@@ -74,7 +74,7 @@ public class GpuResourcePlugin implements ResourcePlugin {
   }
 
   @Override
-  public synchronized NodeResourceUpdaterPlugin getNodeResourceHandlerInstance() {
+  public NodeResourceUpdaterPlugin getNodeResourceHandlerInstance() {
     return resourceDiscoverHandler;
   }