From d5f7aa2285a0b0f6561c64d2321565bbaf5d287b Mon Sep 17 00:00:00 2001
From: Wei-Chiu Chuang <weichiu@apache.org>
Date: Tue, 14 Jan 2020 15:39:59 -0800
Subject: [PATCH] HDFS-13339. Volume reference can't be released and may lead
 to deadlock when DataXceiver does a check volume. Contributed by Jim Brennan,
 Zsolt Venczel.

(cherry picked from commit c675719c3fb0fe5f6b0be624935fdf22bb228e0f)
---
 .../datanode/checker/DatasetVolumeChecker.java      | 13 ++++++++++++-
 .../datanode/checker/TestDatasetVolumeChecker.java  |  9 +++++++++
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/checker/DatasetVolumeChecker.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/checker/DatasetVolumeChecker.java
index 0f59b847dc1..05a9ae83da4 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/checker/DatasetVolumeChecker.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/checker/DatasetVolumeChecker.java
@@ -47,6 +47,7 @@ import java.util.HashSet;
 import java.util.Set;
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.ExecutionException;
+import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicLong;
@@ -104,6 +105,8 @@ public class DatasetVolumeChecker {
   private static final VolumeCheckContext IGNORED_CONTEXT =
       new VolumeCheckContext();
 
+  private final ExecutorService checkVolumeResultHandlerExecutorService;
+
   /**
    * @param conf Configuration object.
    * @param timer {@link Timer} object used for throttling checks.
@@ -165,6 +168,12 @@ public class DatasetVolumeChecker {
                 .setNameFormat("DataNode DiskChecker thread %d")
                 .setDaemon(true)
                 .build()));
+
+    checkVolumeResultHandlerExecutorService = Executors.newCachedThreadPool(
+        new ThreadFactoryBuilder()
+            .setNameFormat("VolumeCheck ResultHandler thread %d")
+            .setDaemon(true)
+            .build());
   }
 
   /**
@@ -295,7 +304,9 @@ public class DatasetVolumeChecker {
       Futures.addCallback(olf.get(),
           new ResultHandler(volumeReference, new HashSet<FsVolumeSpi>(),
           new HashSet<FsVolumeSpi>(),
-          new AtomicLong(1), callback));
+              new AtomicLong(1), callback),
+          checkVolumeResultHandlerExecutorService
+      );
       return true;
     } else {
       IOUtils.cleanup(null, volumeReference);
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/checker/TestDatasetVolumeChecker.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/checker/TestDatasetVolumeChecker.java
index 2a1c824d4ea..08aa1c9a73d 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/checker/TestDatasetVolumeChecker.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/datanode/checker/TestDatasetVolumeChecker.java
@@ -19,11 +19,13 @@
 package org.apache.hadoop.hdfs.server.datanode.checker;
 
 import com.google.common.base.Optional;
+import com.google.common.base.Supplier;
 import com.google.common.util.concurrent.Futures;
 import com.google.common.util.concurrent.ListenableFuture;
 import org.apache.hadoop.hdfs.HdfsConfiguration;
 import org.apache.hadoop.hdfs.server.datanode.fsdataset.*;
 import org.apache.hadoop.hdfs.server.datanode.fsdataset.FsVolumeSpi.VolumeCheckContext;
+import org.apache.hadoop.test.GenericTestUtils;
 import org.apache.hadoop.util.DiskChecker.DiskErrorException;
 import org.apache.hadoop.util.FakeTimer;
 import org.junit.Rule;
@@ -121,6 +123,13 @@ public class TestDatasetVolumeChecker {
           }
         });
 
+    GenericTestUtils.waitFor(new Supplier<Boolean>() {
+      @Override
+      public Boolean get() {
+        return (numCallbackInvocations.get() > 0);
+      }
+    }, 5, 10000);
+
     // Ensure that the check was invoked at least once.
     verify(volume, times(1)).check(any(VolumeCheckContext.class));
     if (result) {