HDFS-17218. Fix some logic

Author: haiyang1987

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/blockmanagement/HeartbeatManager.java

@@ -18,6 +18,7 @@
 package org.apache.hadoop.hdfs.server.blockmanagement;
 
 import java.util.ArrayList;
+import java.util.Collection;
 import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
@@ -30,7 +31,6 @@
 import org.apache.hadoop.hdfs.server.namenode.Namesystem;
 import org.apache.hadoop.hdfs.server.protocol.StorageReport;
 import org.apache.hadoop.hdfs.server.protocol.VolumeFailureSummary;
-import org.apache.hadoop.hdfs.util.LightWeightHashSet;
 import org.apache.hadoop.util.Daemon;
 import org.apache.hadoop.util.StopWatch;
 import org.apache.hadoop.util.Time;
@@ -236,20 +236,18 @@ synchronized void register(final DatanodeDescriptor d) {
       d.updateHeartbeatState(StorageReport.EMPTY_ARRAY, 0L, 0L, 0, 0, null);
       stats.add(d);
     } else {
-      // Only when active NN is out of safe mode.
       if (!blockManager.isPopulatingReplQueues()) {
         return;
       }
       // Remove blocks from excessRedundancyMap by datanode.
-      LightWeightHashSet<BlockInfo> set = blockManager.removeBlocksFromExcessRedundancyMap(d);
-      // Remove blocks from invalidateBlocks in datanode.
-      d.clearInvalidateBlocks();
+      Collection<BlockInfo> excessBlocks = blockManager.removeBlocksFromExcessRedundancyMap(d);
       // Remove blocks from invalidateBlocks in blockManager.
       blockManager.removeBlocksFromInvalidateBlocks(d);
-      // Add blocks into postponed queue and
-      // here add `set != null` to avoid the mock test UT failed.
-      if (set != null && !set.isEmpty()) {
-        for (BlockInfo block: set) {
+      // Remove blocks from invalidateBlocks in datanode.
+      d.clearInvalidateBlocks();
+      // Add blocks into postponed queue, add excessBlocks != null to avoid the mock test UT failed.
+      if (excessBlocks != null && !excessBlocks.isEmpty()) {
+        for (BlockInfo block : excessBlocks) {
           blockManager.postponeBlock(block);
         }
       }