HDFS-17393. Remove unused FSNamesytemLock cond in FSNamesystem (#6567)

Author: ZanderXu

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSNamesystem.java

@@ -176,7 +176,6 @@
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.TimeUnit;
-import java.util.concurrent.locks.Condition;
 import java.util.concurrent.locks.ReentrantLock;
 import java.util.concurrent.locks.ReentrantReadWriteLock;
 import java.util.function.Supplier;
@@ -662,7 +661,6 @@ private boolean isFromProxyUser(CallerContext ctx) {
   private KeyProviderCryptoExtension provider = null;
 
   private volatile boolean imageLoaded = false;
-  private final Condition cond;
 
   private final FSImage fsImage;
 
@@ -704,7 +702,6 @@ void setImageLoaded() {
     try {
       setImageLoaded(true);
       dir.markNameCacheInitialized();
-      cond.signalAll();
     } finally {
       writeUnlock("setImageLoaded");
     }
@@ -875,7 +872,6 @@ static FSNamesystem loadFromDisk(Configuration conf) throws IOException {
         conf.get(HADOOP_CALLER_CONTEXT_SEPARATOR_KEY,
             HADOOP_CALLER_CONTEXT_SEPARATOR_DEFAULT);
     fsLock = new FSNamesystemLock(conf, detailedLockHoldTimeMetrics);
-    cond = fsLock.newWriteLockCondition();
     cpLock = new ReentrantLock();
 
     this.fsImage = fsImage;