compositor-worker: Share a thread and an isolate for compositor workers.

Source/core/workers/WorkerThread.cpp

 /*
  * Copyright (C) 2008 Apple Inc. All Rights Reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 11 matching lines @@
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *
  */
 
 #include "config.h"
 
 #include "core/workers/WorkerThread.h"
 
 #include "bindings/core/v8/ScriptSourceCode.h"
-#include "bindings/core/v8/V8GCController.h"
-#include "bindings/core/v8/V8Initializer.h"
 #include "core/dom/Microtask.h"
 #include "core/inspector/InspectorInstrumentation.h"
 #include "core/inspector/WorkerInspectorController.h"
 #include "core/workers/DedicatedWorkerGlobalScope.h"
 #include "core/workers/WorkerClients.h"
 #include "core/workers/WorkerReportingProxy.h"
 #include "core/workers/WorkerThreadStartupData.h"
 #include "platform/PlatformThreadData.h"
 #include "platform/Task.h"
 #include "platform/ThreadSafeFunctional.h"
@@ skipping 205 matching lines @@
     bool m_isInstrumented;
 };
 
 WorkerThread::WorkerThread(PassRefPtr<WorkerLoaderProxy> workerLoaderProxy, WorkerReportingProxy& workerReportingProxy)
     : m_started(false)
     , m_terminated(false)
     , m_shutdown(false)
     , m_workerLoaderProxy(workerLoaderProxy)
     , m_workerReportingProxy(workerReportingProxy)
     , m_webScheduler(nullptr)
-    , m_isolate(nullptr)
     , m_shutdownEvent(adoptPtr(Platform::current()->createWaitableEvent()))
     , m_terminationEvent(adoptPtr(Platform::current()->createWaitableEvent()))
 {
     MutexLocker lock(threadSetMutex());
     workerThreads().add(this);
 }
 
 WorkerThread::~WorkerThread()
 {
     MutexLocker lock(threadSetMutex());
@@ skipping 38 matching lines @@
         // The worker was terminated before the thread had a chance to run.
         if (m_terminated) {
             // Notify the proxy that the WorkerGlobalScope has been disposed of.
             // This can free this thread object, hence it must not be touched afterwards.
             m_workerReportingProxy.workerThreadTerminated();
             return;
         }
 
         m_microtaskRunner = adoptPtr(new WorkerMicrotaskRunner(this));
         backingThread().addTaskObserver(m_microtaskRunner.get());
-        backingThread().initialize();
+        initializeBackingThread();
 
-        m_isolate = initializeIsolate();
+        // Make sure the isolate is intialized correctly.
+        m_isolateWrapper = createIsolateWrapper();
         m_workerGlobalScope = createWorkerGlobalScope(startupData);
         m_workerGlobalScope->scriptLoaded(sourceCode.length(), cachedMetaData.get() ? cachedMetaData->size() : 0);
 
         PlatformThreadData::current().threadTimers().setSharedTimer(adoptPtr(new WorkerSharedTimer(this)));
     }
     m_webScheduler = backingThread().platformThread().scheduler();
 
     // The corresponding call to stopRunLoop() is in ~WorkerScriptController().
     didStartRunLoop();
 
@@ skipping 20 matching lines @@
 {
     ASSERT(isCurrentThread());
     {
         MutexLocker lock(m_threadStateMutex);
         ASSERT(!m_shutdown);
         m_shutdown = true;
     }
 
     PlatformThreadData::current().threadTimers().setSharedTimer(nullptr);
     workerGlobalScope()->dispose();
-    willDestroyIsolate();
+    m_isolateWrapper->willDestroy();
 
     // This should be called before we start the shutdown procedure.
     workerReportingProxy().willDestroyWorkerGlobalScope();
 
     // The below assignment will destroy the context, which will in turn notify messaging proxy.
     // We cannot let any objects survive past thread exit, because no other thread will run GC or otherwise destroy them.
     // If Oilpan is enabled, we detach of the context/global scope, with the final heap cleanup below sweeping it out.
 #if !ENABLE(OILPAN)
     ASSERT(m_workerGlobalScope->hasOneRef());
 #endif
     m_workerGlobalScope->notifyContextDestroyed();
     m_workerGlobalScope = nullptr;
 
     backingThread().removeTaskObserver(m_microtaskRunner.get());
-    backingThread().shutdown();
-    destroyIsolate();
+    shutdownBackingThread();
+    m_isolateWrapper.clear();
 
     m_microtaskRunner = nullptr;
 
     // Notify the proxy that the WorkerGlobalScope has been disposed of.
     // This can free this thread object, hence it must not be touched afterwards.
     workerReportingProxy().workerThreadTerminated();
 
     m_terminationEvent->signal();
 
     // Clean up PlatformThreadData before WTF::WTFThreadData goes away!
@@ skipping 62 matching lines @@
     ASSERT(isCurrentThread());
     Platform::current()->didStartWorkerRunLoop();
 }
 
 void WorkerThread::didStopRunLoop()
 {
     ASSERT(isCurrentThread());
     Platform::current()->didStopWorkerRunLoop();
 }
 
+v8::Isolate* WorkerThread::isolate()
+{
+    return m_isolateWrapper ? m_isolateWrapper->isolate() : nullptr;

[haraken, 2015/06/02 02:14:49]

v8::Isolate* must not be null. Can we change this to ASSERT(m_isolateWrapper)?

[sadrul, 2015/06/02 02:48:28]

Done.

+}
+
+void WorkerThread::initializeBackingThread()
+{

[haraken, 2015/06/02 02:14:49]

Add ASSERT(!isMainThread()).

[sadrul, 2015/06/02 02:48:28]

Done. (added ASSERT(isCurrentThread()); instead)

+    backingThread().initialize();
+}
+
+void WorkerThread::shutdownBackingThread()
+{
+    backingThread().shutdown();

[haraken, 2015/06/02 02:14:49]

Add ASSERT(!isMainThread()).

[sadrul, 2015/06/02 02:48:28]

Ditto.

+}
+
 void WorkerThread::terminateAndWaitForAllWorkers()
 {
     // Keep this lock to prevent WorkerThread instances from being destroyed.
     MutexLocker lock(threadSetMutex());
     HashSet<WorkerThread*> threads = workerThreads();
     for (WorkerThread* thread : threads)
         thread->stopInShutdownSequence();
 
     for (WorkerThread* thread : threads)
         thread->terminationEvent()->wait();
@@ skipping 30 matching lines @@
 void WorkerThread::postTask(const WebTraceLocation& location, PassOwnPtr<ExecutionContextTask> task)
 {
     backingThread().postTask(location, WorkerThreadTask::create(*this, task, true).leakPtr());
 }
 
 void WorkerThread::postDelayedTask(const WebTraceLocation& location, PassOwnPtr<ExecutionContextTask> task, long long delayMs)
 {
     backingThread().postDelayedTask(location, WorkerThreadTask::create(*this, task, true).leakPtr(), delayMs);
 }
 
-v8::Isolate* WorkerThread::initializeIsolate()
+PassOwnPtr<WorkerIsolateWrapper> WorkerThread::createIsolateWrapper()
 {
-    ASSERT(isCurrentThread());
-    ASSERT(!m_isolate);
-    v8::Isolate* isolate = V8PerIsolateData::initialize();
-    V8Initializer::initializeWorker(isolate);
-
-    m_interruptor = adoptPtr(new V8IsolateInterruptor(isolate));
-    ThreadState::current()->addInterruptor(m_interruptor.get());
-    ThreadState::current()->registerTraceDOMWrappers(isolate, V8GCController::traceDOMWrappers);
-
-    return isolate;
-}
-
-void WorkerThread::willDestroyIsolate()
-{
-    ASSERT(isCurrentThread());
-    ASSERT(m_isolate);
-    V8PerIsolateData::willBeDestroyed(m_isolate);
-    ThreadState::current()->removeInterruptor(m_interruptor.get());
-}
-
-void WorkerThread::destroyIsolate()
-{
-    ASSERT(isCurrentThread());
-    V8PerIsolateData::destroy(m_isolate);
-    m_isolate = nullptr;
+    return WorkerIsolateWrapper::createDefault();
 }
 
 void WorkerThread::terminateV8Execution()
 {
     ASSERT(isMainThread());
     m_workerGlobalScope->script()->willScheduleExecutionTermination();
-    v8::V8::TerminateExecution(m_isolate);
+    m_isolateWrapper->terminateExecution();
 }
 
 void WorkerThread::appendDebuggerTask(PassOwnPtr<WebThread::Task> task)
 {
     m_debuggerMessageQueue.append(task);
 }
 
 MessageQueueWaitResult WorkerThread::runDebuggerTask(WaitMode waitMode)
 {
     ASSERT(isCurrentThread());
@@ skipping 26 matching lines @@
     InspectorInstrumentation::didLeaveNestedRunLoop(m_workerGlobalScope.get());
 }
 
 void WorkerThread::setWorkerInspectorController(WorkerInspectorController* workerInspectorController)
 {
     MutexLocker locker(m_workerInspectorControllerMutex);
     m_workerInspectorController = workerInspectorController;
 }
 
 } // namespace blink