HDFS-9294. DFSClient deadlock when close file and failed to renew lease. Contributed by Brahma Reddy Battula

hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt

@@ -38,6 +38,9 @@ Release 2.6.4 - UNRELEASED
     HDFS-8767. RawLocalFileSystem.listStatus() returns null for UNIX pipefile.
     (Kanaka Kumar Avvaru via wheat9)
 
+    HDFS-9294. DFSClient deadlock when close file and failed to renew lease.
+    (Brahma Reddy Battula via szetszwo)
+
 Release 2.6.3 - 2015-12-17
 
   INCOMPATIBLE CHANGES

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSOutputStream.java

@@ -2171,13 +2171,15 @@ public class DFSOutputStream extends FSOutputSummer
    * Aborts this output stream and releases any system 
    * resources associated with this stream.
    */
-  synchronized void abort() throws IOException {
-    if (closed) {
-      return;
+  void abort() throws IOException {
+    synchronized (this) {
+      if (closed) {
+        return;
+      }
+      streamer.setLastException(new IOException("Lease timeout of "
+              + (dfsClient.getHdfsTimeout() / 1000) + " seconds expired."));
+      closeThreads(true);
     }
-    streamer.setLastException(new IOException("Lease timeout of "
-        + (dfsClient.getHdfsTimeout()/1000) + " seconds expired."));
-    closeThreads(true);
     dfsClient.endFileLease(fileId);
   }
 
@@ -2204,39 +2206,42 @@ public class DFSOutputStream extends FSOutputSummer
    * resources associated with this stream.
    */
   @Override
-  public synchronized void close() throws IOException {
-    if (closed) {
-      IOException e = lastException.getAndSet(null);
-      if (e == null)
-        return;
-      else
-        throw e;
-    }
+  public void close() throws IOException {
+    synchronized (this) {
+      if (closed) {
+        IOException e = lastException.getAndSet(null);
+        if (e == null)
+          return;
+        else
+          throw e;
+      }
 
-    try {
-      flushBuffer();       // flush from all upper layers
+      try {
+        flushBuffer();       // flush from all upper layers
 
-      if (currentPacket != null) { 
-        waitAndQueueCurrentPacket();
-      }
+        if (currentPacket != null) {
+          waitAndQueueCurrentPacket();
+        }
 
-      if (bytesCurBlock != 0) {
-        // send an empty packet to mark the end of the block
-        currentPacket = createPacket(0, 0, bytesCurBlock, currentSeqno++);
-        currentPacket.lastPacketInBlock = true;
-        currentPacket.syncBlock = shouldSyncBlock;
-      }
+        if (bytesCurBlock != 0) {
+          // send an empty packet to mark the end of the block
+          currentPacket = createPacket(0, 0, bytesCurBlock, currentSeqno++);
+          currentPacket.lastPacketInBlock = true;
+          currentPacket.syncBlock = shouldSyncBlock;
+        }
 
-      flushInternal();             // flush all data to Datanodes
-      // get last block before destroying the streamer
-      ExtendedBlock lastBlock = streamer.getBlock();
-      closeThreads(false);
-      completeFile(lastBlock);
-      dfsClient.endFileLease(fileId);
-    } catch (ClosedChannelException e) {
-    } finally {
-      closed = true;
+        flushInternal();             // flush all data to Datanodes
+        // get last block before destroying the streamer
+        ExtendedBlock lastBlock = streamer.getBlock();
+        closeThreads(false);
+        completeFile(lastBlock);
+
+      } catch (ClosedChannelException e) {
+      } finally {
+        closed = true;
+      }
     }
+    dfsClient.endFileLease(fileId);
   }
 
   // should be called holding (this) lock since setTestFilename() may