diff --git a/core/src/main/scala/org/apache/spark/SparkContext.scala b/core/src/main/scala/org/apache/spark/SparkContext.scala index 9f0f6074229ddcce8dcffeed5388a5763edb7092..25a3d609a6b094a701b403107904ff707ecd386f 100644 --- a/core/src/main/scala/org/apache/spark/SparkContext.scala +++ b/core/src/main/scala/org/apache/spark/SparkContext.scala @@ -1757,8 +1757,26 @@ class SparkContext(config: SparkConf) extends Logging { */ def listJars(): Seq[String] = addedJars.keySet.toSeq - // Shut down the SparkContext. - def stop() { + /** + * Shut down the SparkContext. + */ + def stop(): Unit = { + if (env.rpcEnv.isInRPCThread) { + // `stop` will block until all RPC threads exit, so we cannot call stop inside a RPC thread. + // We should launch a new thread to call `stop` to avoid dead-lock. + new Thread("stop-spark-context") { + setDaemon(true) + + override def run(): Unit = { + _stop() + } + }.start() + } else { + _stop() + } + } + + private def _stop() { if (LiveListenerBus.withinListenerThread.value) { throw new SparkException( s"Cannot stop SparkContext within listener thread of ${LiveListenerBus.name}") diff --git a/core/src/main/scala/org/apache/spark/rpc/RpcEnv.scala b/core/src/main/scala/org/apache/spark/rpc/RpcEnv.scala index 579122868afc8d42119a4a0c1f6148c86d8e8f3d..bbc416381490bc3d658b89fbf5c3570d96d3f098 100644 --- a/core/src/main/scala/org/apache/spark/rpc/RpcEnv.scala +++ b/core/src/main/scala/org/apache/spark/rpc/RpcEnv.scala @@ -147,6 +147,10 @@ private[spark] abstract class RpcEnv(conf: SparkConf) { */ def openChannel(uri: String): ReadableByteChannel + /** + * Return if the current thread is a RPC thread. + */ + def isInRPCThread: Boolean } /** diff --git a/core/src/main/scala/org/apache/spark/rpc/netty/Dispatcher.scala b/core/src/main/scala/org/apache/spark/rpc/netty/Dispatcher.scala index a02cf30a5d8317c65123019a93344ad2ab29c0bc..67baabd2cbff26f41255d2c16d9058308bdd4bd7 100644 --- a/core/src/main/scala/org/apache/spark/rpc/netty/Dispatcher.scala +++ b/core/src/main/scala/org/apache/spark/rpc/netty/Dispatcher.scala @@ -201,6 +201,7 @@ private[netty] class Dispatcher(nettyEnv: NettyRpcEnv) extends Logging { /** Message loop used for dispatching messages. */ private class MessageLoop extends Runnable { override def run(): Unit = { + NettyRpcEnv.rpcThreadFlag.value = true try { while (true) { try { diff --git a/core/src/main/scala/org/apache/spark/rpc/netty/NettyRpcEnv.scala b/core/src/main/scala/org/apache/spark/rpc/netty/NettyRpcEnv.scala index e51649a1ecce9b01ea070fd5b3e709807f12260c..0b8cd144a2161a9273fa580faeae26bc1a08a5fc 100644 --- a/core/src/main/scala/org/apache/spark/rpc/netty/NettyRpcEnv.scala +++ b/core/src/main/scala/org/apache/spark/rpc/netty/NettyRpcEnv.scala @@ -408,10 +408,13 @@ private[netty] class NettyRpcEnv( } + override def isInRPCThread: Boolean = NettyRpcEnv.rpcThreadFlag.value } private[netty] object NettyRpcEnv extends Logging { + private[netty] val rpcThreadFlag = new DynamicVariable[Boolean](false) + /** * When deserializing the [[NettyRpcEndpointRef]], it needs a reference to [[NettyRpcEnv]]. * Use `currentEnv` to wrap the deserialization codes. E.g., diff --git a/core/src/test/scala/org/apache/spark/rpc/RpcEnvSuite.scala b/core/src/test/scala/org/apache/spark/rpc/RpcEnvSuite.scala index acdf21df9a16157b3f1be95945fb3a94a6ffdead..aa0705987d837225653b2987f06dfc2605f05c82 100644 --- a/core/src/test/scala/org/apache/spark/rpc/RpcEnvSuite.scala +++ b/core/src/test/scala/org/apache/spark/rpc/RpcEnvSuite.scala @@ -870,6 +870,19 @@ abstract class RpcEnvSuite extends SparkFunSuite with BeforeAndAfterAll { verify(endpoint, never()).onDisconnected(any()) verify(endpoint, never()).onNetworkError(any(), any()) } + + test("isInRPCThread") { + val rpcEndpointRef = env.setupEndpoint("isInRPCThread", new RpcEndpoint { + override val rpcEnv = env + + override def receiveAndReply(context: RpcCallContext): PartialFunction[Any, Unit] = { + case m => context.reply(rpcEnv.isInRPCThread) + } + }) + assert(rpcEndpointRef.askWithRetry[Boolean]("hello") === true) + assert(env.isInRPCThread === false) + env.stop(rpcEndpointRef) + } } class UnserializableClass