From 98b11bdde4c792f9b817d7fed46dfcad5195140e Mon Sep 17 00:00:00 2001
From: "Penn (Dapeng) Zhang" <zdapeng@google.com>
Date: Wed, 15 Jan 2020 12:42:33 -0800
Subject: [PATCH] core,netty: fix a race for channelz at server transport
 creation

---
 .../main/java/io/grpc/internal/ServerImpl.java  |  4 +++-
 .../main/java/io/grpc/netty/NettyServer.java    | 17 ++++-------------
 2 files changed, 7 insertions(+), 14 deletions(-)

diff --git a/core/src/main/java/io/grpc/internal/ServerImpl.java b/core/src/main/java/io/grpc/internal/ServerImpl.java
index 85d857932309..4df2722c93d9 100644
--- a/core/src/main/java/io/grpc/internal/ServerImpl.java
+++ b/core/src/main/java/io/grpc/internal/ServerImpl.java
@@ -439,7 +439,9 @@ class TransportShutdownNow implements Runnable {
           @Override public void run() {}
         }, null);
       }
-      channelz.addServerSocket(ServerImpl.this, transport);
+      synchronized (lock) {
+        channelz.addServerSocket(ServerImpl.this, transport);
+      }
     }
 
     @Override
diff --git a/netty/src/main/java/io/grpc/netty/NettyServer.java b/netty/src/main/java/io/grpc/netty/NettyServer.java
index 5c400198817a..af48b0f42f66 100644
--- a/netty/src/main/java/io/grpc/netty/NettyServer.java
+++ b/netty/src/main/java/io/grpc/netty/NettyServer.java
@@ -251,19 +251,10 @@ public void operationComplete(ChannelFuture future) throws Exception {
       throw new IOException("Failed to bind", future.cause());
     }
     channel = future.channel();
-    Future<?> channelzFuture = channel.eventLoop().submit(new Runnable() {
-      @Override
-      public void run() {
-        InternalInstrumented<SocketStats> listenSocket = new ListenSocket(channel);
-        listenSocketStats.set(listenSocket);
-        channelz.addListenSocket(listenSocket);
-      }
-    });
-    try {
-      channelzFuture.await();
-    } catch (InterruptedException ex) {
-      throw new RuntimeException("Interrupted while registering listen socket to channelz", ex);
-    }
+
+    InternalInstrumented<SocketStats> listenSocket = new ListenSocket(channel);
+    listenSocketStats.set(listenSocket);
+    channelz.addListenSocket(listenSocket);
   }
 
   @Override