From 4475d8bfe76a9939a4e611fe7903fbc17f180137 Mon Sep 17 00:00:00 2001
From: AngersZhuuuu <angers.zhu@gmail.com>
Date: Sat, 25 Sep 2021 18:17:44 +0800
Subject: [PATCH] HDFS-16235. Fix Deadlock in LeaseRenewer for static remove
 method (#3472)

(cherry picked from commit 5f9321a5d4112e7b4ee9e6b948ce46a2b152a2db)
---
 .../java/org/apache/hadoop/hdfs/client/impl/LeaseRenewer.java | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/client/impl/LeaseRenewer.java b/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/client/impl/LeaseRenewer.java
index 6b4c8994544..fcacdaa6a73 100644
--- a/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/client/impl/LeaseRenewer.java
+++ b/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/client/impl/LeaseRenewer.java
@@ -96,7 +96,9 @@ public class LeaseRenewer {
    * @param renewer Instance to be cleared from Factory
    */
   public static void remove(LeaseRenewer renewer) {
-    Factory.INSTANCE.remove(renewer);
+    synchronized (renewer) {
+      Factory.INSTANCE.remove(renewer);
+    }
   }
 
   /**