HDFS-13885. Add debug logs in dfsclient around decrypting EDEK. Contributed by Kitti Nanasi.

Signed-off-by: Xiao Chen <xiao@apache.org>

hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/DFSClient.java

@@ -953,8 +953,12 @@ public class DFSClient implements java.io.Closeable, RemotePeerFactory,
       final CryptoCodec codec = HdfsKMSUtil.getCryptoCodec(conf, feInfo);
       KeyVersion decrypted;
       try (TraceScope ignored = tracer.newScope("decryptEDEK")) {
+        LOG.debug("Start decrypting EDEK for file: {}, output stream: 0x{}",
+            dfsos.getSrc(), Integer.toHexString(dfsos.hashCode()));
         decrypted = HdfsKMSUtil.decryptEncryptedDataEncryptionKey(feInfo,
           getKeyProvider());
+        LOG.debug("Decrypted EDEK for file: {}, output stream: 0x{}",
+            dfsos.getSrc(), Integer.toHexString(dfsos.hashCode()));
       }
       final CryptoOutputStream cryptoOut =
           new CryptoOutputStream(dfsos, codec,