HDFS-15111. stopStandbyServices() should log which service state it is transitioning from. Contributed by Xieming Li.

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

@@ -94,6 +94,7 @@ import org.apache.hadoop.hdfs.protocol.HdfsConstants;
 import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_STORAGE_POLICY_ENABLED_KEY;
 import static org.apache.hadoop.hdfs.server.namenode.FSDirStatAndListingOp.*;
 import static org.apache.hadoop.ha.HAServiceProtocol.HAServiceState.ACTIVE;
+import static org.apache.hadoop.ha.HAServiceProtocol.HAServiceState.STANDBY;
 import static org.apache.hadoop.ha.HAServiceProtocol.HAServiceState.OBSERVER;
 
 import org.apache.hadoop.hdfs.protocol.ErasureCodingPolicyInfo;
@@ -1439,7 +1440,8 @@ public class FSNamesystem implements Namesystem, FSNamesystemMBean,
 
   /** Stop services required in standby state */
   void stopStandbyServices() throws IOException {
-    LOG.info("Stopping services started for standby state");
+    HAServiceState curState = getState() == OBSERVER? OBSERVER : STANDBY;
+    LOG.info("Stopping services started for {} state", curState);
     if (standbyCheckpointer != null) {
       standbyCheckpointer.stop();
     }