From 269896da132a3f6dee8ac17e1b8525f7dc30ab90 Mon Sep 17 00:00:00 2001
From: violetagg <vgeorgieva@pivotal.io>
Date: Tue, 11 Feb 2020 21:24:41 +0200
Subject: [PATCH] When BlockHound is installed, do not report
 GlobalEventExecutor/SingleThreadEventExecutor#takeTask as blocking call.
 (#10020)

Motivation:

GlobalEventExecutor/SingleThreadEventExecutor#taskQueue is BlockingQueue.

Modifications:

Add allowBlockingCallsInside configuration for GlobalEventExecutor/SingleThreadEventExecutor#takeTask.

Result:

Fixes #9984
When BlockHound is installed, GlobalEventExecutor/SingleThreadEventExecutor#takeTask is not reported as a blocking call.
---
 .../java/io/netty/util/internal/Hidden.java   |  7 ++++
 .../NettyBlockHoundIntegrationTest.java       | 34 +++++++++++++++++++
 2 files changed, 41 insertions(+)

diff --git a/common/src/main/java/io/netty/util/internal/Hidden.java b/common/src/main/java/io/netty/util/internal/Hidden.java
index c0e9bba538..52742f181c 100644
--- a/common/src/main/java/io/netty/util/internal/Hidden.java
+++ b/common/src/main/java/io/netty/util/internal/Hidden.java
@@ -62,6 +62,13 @@ class Hidden {
                     "confirmShutdown"
             );
 
+            builder.allowBlockingCallsInside("io.netty.util.concurrent.GlobalEventExecutor",
+                    "takeTask");
+
+            builder.allowBlockingCallsInside(
+                    "io.netty.util.concurrent.SingleThreadEventExecutor",
+                    "takeTask");
+
             builder.allowBlockingCallsInside(
                     "io.netty.handler.ssl.SslHandler",
                     "handshake"
diff --git a/transport-blockhound-tests/src/test/java/io/netty/util/internal/NettyBlockHoundIntegrationTest.java b/transport-blockhound-tests/src/test/java/io/netty/util/internal/NettyBlockHoundIntegrationTest.java
index 489785fbd1..3dcd793a15 100644
--- a/transport-blockhound-tests/src/test/java/io/netty/util/internal/NettyBlockHoundIntegrationTest.java
+++ b/transport-blockhound-tests/src/test/java/io/netty/util/internal/NettyBlockHoundIntegrationTest.java
@@ -35,9 +35,13 @@ import io.netty.handler.ssl.SslProvider;
 import io.netty.handler.ssl.util.InsecureTrustManagerFactory;
 import io.netty.handler.ssl.util.SelfSignedCertificate;
 import io.netty.util.ReferenceCountUtil;
+import io.netty.util.concurrent.DefaultThreadFactory;
+import io.netty.util.concurrent.EventExecutor;
 import io.netty.util.concurrent.GlobalEventExecutor;
 import io.netty.util.concurrent.ImmediateEventExecutor;
 import io.netty.util.concurrent.ImmediateExecutor;
+import io.netty.util.concurrent.ScheduledFuture;
+import io.netty.util.concurrent.SingleThreadEventExecutor;
 import io.netty.util.internal.Hidden.NettyBlockHoundIntegration;
 import org.hamcrest.Matchers;
 import org.junit.BeforeClass;
@@ -48,6 +52,7 @@ import reactor.blockhound.integration.BlockHoundIntegration;
 
 import java.net.InetSocketAddress;
 import java.util.ServiceLoader;
+import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.Executor;
 import java.util.concurrent.ExecutorService;
@@ -93,6 +98,35 @@ public class NettyBlockHoundIntegrationTest {
         }
     }
 
+    @Test(timeout = 5000L)
+    public void testGlobalEventExecutorTakeTask() throws InterruptedException {
+        testEventExecutorTakeTask(GlobalEventExecutor.INSTANCE);
+    }
+
+    @Test(timeout = 5000L)
+    public void testSingleThreadEventExecutorTakeTask() throws InterruptedException {
+        SingleThreadEventExecutor executor =
+                new SingleThreadEventExecutor(new DefaultThreadFactory("test")) {
+                    @Override
+                    protected void run() {
+                        while (!confirmShutdown()) {
+                            Runnable task = takeTask();
+                            if (task != null) {
+                                task.run();
+                            }
+                        }
+                    }
+                };
+        testEventExecutorTakeTask(executor);
+    }
+
+    private static void testEventExecutorTakeTask(EventExecutor eventExecutor) throws InterruptedException {
+        CountDownLatch latch = new CountDownLatch(1);
+        ScheduledFuture<?> f = eventExecutor.schedule(latch::countDown, 10, TimeUnit.MILLISECONDS);
+        f.sync();
+        latch.await();
+    }
+
     // Tests copied from io.netty.handler.ssl.SslHandlerTest
     @Test
     public void testHandshakeWithExecutorThatExecuteDirectory() throws Exception {