Kill worker process by way of a sync IPC message before it cleans up.

content/worker/worker_thread.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/worker/worker_thread.h"
 
 #include "base/command_line.h"
 #include "base/lazy_instance.h"
 #include "base/threading/thread_local.h"
 #include "content/child/appcache/appcache_dispatcher.h"
 #include "content/child/appcache/appcache_frontend_impl.h"
 #include "content/child/db_message_filter.h"
 #include "content/child/indexed_db/indexed_db_message_filter.h"
 #include "content/child/runtime_features.h"
 #include "content/child/web_database_observer_impl.h"
+#include "content/common/child_process_messages.h"
 #include "content/common/worker_messages.h"
 #include "content/public/common/content_switches.h"
 #include "content/worker/websharedworker_stub.h"
 #include "content/worker/worker_webkitplatformsupport_impl.h"
 #include "ipc/ipc_sync_channel.h"
 #include "third_party/WebKit/public/platform/WebBlobRegistry.h"
 #include "third_party/WebKit/public/web/WebDatabase.h"
 #include "third_party/WebKit/public/web/WebKit.h"
 #include "third_party/WebKit/public/web/WebRuntimeFeatures.h"
 #include "webkit/glue/webkit_glue.h"
@@ skipping 23 matching lines @@
   channel()->AddFilter(db_message_filter_.get());
 
   indexed_db_message_filter_ = new IndexedDBMessageFilter(
       thread_safe_sender());
   channel()->AddFilter(indexed_db_message_filter_.get());
 
   const CommandLine& command_line = *CommandLine::ForCurrentProcess();
   SetRuntimeFeaturesDefaultsAndUpdateFromArgs(command_line);
 }
 
+void WorkerThread::OnShutdown() {
+  // The worker process is to be shut down gracefully. Ask the browser
+  // process to shut it down forcefully instead and wait on the message, so that
+  // there are no races between threads when the process is shutting down.
+  Send(new WorkerProcessHostMsg_ForceKillWorker());
+}
+
 WorkerThread::~WorkerThread() {
 }
 
 void WorkerThread::Shutdown() {
   ChildThread::Shutdown();
 
   // Shutdown in reverse of the initialization order.
   channel()->RemoveFilter(indexed_db_message_filter_.get());
   indexed_db_message_filter_ = NULL;
 
@@ skipping 14 matching lines @@
     return true;
 
   bool handled = true;
   IPC_BEGIN_MESSAGE_MAP(WorkerThread, msg)
     IPC_MESSAGE_HANDLER(WorkerProcessMsg_CreateWorker, OnCreateWorker)
     IPC_MESSAGE_UNHANDLED(handled = false)
   IPC_END_MESSAGE_MAP()
   return handled;
 }
 
+bool WorkerThread::OnMessageReceived(const IPC::Message& msg) {
+  bool handled = true;
+  IPC_BEGIN_MESSAGE_MAP(WorkerThread, msg)
+    IPC_MESSAGE_HANDLER(ChildProcessMsg_Shutdown, OnShutdown)
+    IPC_MESSAGE_UNHANDLED(handled = ChildThread::OnMessageReceived(msg))
+  IPC_END_MESSAGE_MAP()
+  return handled;
+}
+
 void WorkerThread::OnCreateWorker(
     const WorkerProcessMsg_CreateWorker_Params& params) {
   WorkerAppCacheInitInfo appcache_init_info(
       params.creator_process_id,
       params.shared_worker_appcache_id);
 
   // WebSharedWorkerStub own themselves.
   new WebSharedWorkerStub(params.name, params.route_id, appcache_init_info);
 }
 
 // The browser process is likely dead. Terminate all workers.
 void WorkerThread::OnChannelError() {
   set_on_channel_error_called(true);
 
   for (WorkerStubsList::iterator it = worker_stubs_.begin();
        it != worker_stubs_.end(); ++it) {
     (*it)->OnChannelError();
   }
 }
 
 void WorkerThread::RemoveWorkerStub(WebSharedWorkerStub* stub) {
   worker_stubs_.erase(stub);
 }
 
 void WorkerThread::AddWorkerStub(WebSharedWorkerStub* stub) {
   worker_stubs_.insert(stub);
 }
 
 }  // namespace content