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

Source/modules/compositorworker/CompositorWorkerManagerTest.cpp

Index: Source/modules/compositorworker/CompositorWorkerManagerTest.cpp
diff --git a/Source/modules/compositorworker/CompositorWorkerManagerTest.cpp b/Source/modules/compositorworker/CompositorWorkerManagerTest.cpp
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index 0000000000000000000000000000000000000000..c9ef37917748350cb3609f122f2e58a42a477908
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+++ b/Source/modules/compositorworker/CompositorWorkerManagerTest.cpp
@@ -0,0 +1,231 @@
+// Copyright 2015 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 "config.h"
+#include "modules/compositorworker/CompositorWorkerManager.h"
+
+#include "bindings/core/v8/ScriptSourceCode.h"
+#include "core/testing/DummyPageHolder.h"
+#include "core/workers/WorkerLoaderProxy.h"
+#include "core/workers/WorkerObjectProxy.h"
+#include "core/workers/WorkerReportingProxy.h"
+#include "core/workers/WorkerThreadStartupData.h"
+#include "modules/compositorworker/CompositorWorkerThread.h"
+#include "platform/NotImplemented.h"
+#include "platform/ThreadSafeFunctional.h"
+#include "public/platform/Platform.h"
+#include "public/platform/WebWaitableEvent.h"
+#include <gtest/gtest.h>
+
+namespace blink {
+namespace {
+
+class TestCompositorWorkerThread : public CompositorWorkerThread {
+public:
+    TestCompositorWorkerThread(WorkerLoaderProxyProvider* loaderProxyProvider, WorkerObjectProxy& objectProxy, double timeOrigin, WebWaitableEvent* startEvent)
+        : CompositorWorkerThread(WorkerLoaderProxy::create(loaderProxyProvider), objectProxy, timeOrigin)
+        , m_startEvent(startEvent)
+    {
+    }
+
+    ~TestCompositorWorkerThread() override { }
+
+    void setCallbackAfterV8Termination(PassOwnPtr<Function<void()>> callback)
+    {
+        m_v8TerminationCallback = callback;
+    }
+
+private:
+    // WorkerThread:
+    void didStartRunLoop() override
+    {
+        m_startEvent->signal();
+    }
+    void terminateV8Execution() override
+    {
+        CompositorWorkerThread::terminateV8Execution();
+        if (m_v8TerminationCallback)
+            (*m_v8TerminationCallback)();
+    }
+
+    WebWaitableEvent* m_startEvent;
+    OwnPtr<Function<void()>> m_v8TerminationCallback;
+};
+
+} // namespace
+
+class CompositorWorkerManagerTest : public testing::Test {
+public:
+    void SetUp() override
+    {
+        m_page = DummyPageHolder::create();
+        m_objectProxy = WorkerObjectProxy::create(&m_page->document(), nullptr);

[sof, 2015/06/07 06:17:11]

Is it valid to pass in a null WorkerMessagingProxy, won't the object proxy try
to relay calls to a non-existent object?

+        m_securityOrigin = SecurityOrigin::create(KURL(ParsedURLString, "http://fake.url/"));
+    }
+
+    void TearDown() override
+    {
+        ASSERT(!managerHasThread());
+        ASSERT(!managerHasIsolate());
+        m_page.clear();
+    }
+
+    PassRefPtr<TestCompositorWorkerThread> createCompositorWorker(WebWaitableEvent* startEvent)
+    {
+        TestCompositorWorkerThread* workerThread = new TestCompositorWorkerThread(nullptr, *m_objectProxy, 0, startEvent);
+        workerThread->start(WorkerThreadStartupData::create(
+            KURL(ParsedURLString, "http://fake.url/"),
+            "fake user agent",
+            "//fake source code",
+            nullptr,
+            DontPauseWorkerGlobalScopeOnStart,
+            adoptPtr(new Vector<CSPHeaderAndType>()),
+            m_securityOrigin.get(),
+            WorkerClients::create(),

[sof, 2015/06/07 06:17:11]

This is problematic for threads attached to an Oilpan heap and you create the
worker while stopping a worker thread. i.e., we do not allow allocations during
shutdowns.

[sof, 2015/06/07 06:28:19]

btw, I suspect the handling of WorkerClients creation can be simplified. Often,
the thread creating a worker thread only passes in an empty&default
WorkerClients.

+            V8CacheOptionsDefault));
+        return adoptRef(workerThread);
+    }
+
+    void createWorkerAdapter(RefPtr<CompositorWorkerThread>* workerThread, WebWaitableEvent* creationEvent)
+    {
+        *workerThread = createCompositorWorker(creationEvent);
+    }
+
+    // Attempts to run some simple script for |worker|.
+    void checkWorkerCanExecuteScript(WorkerThread* worker)
+    {
+        OwnPtr<WebWaitableEvent> waitEvent = adoptPtr(Platform::current()->createWaitableEvent());
+        worker->backingThread().platformThread().postTask(FROM_HERE, threadSafeBind(&CompositorWorkerManagerTest::executeScriptInWorker, AllowCrossThreadAccess(this),
+            AllowCrossThreadAccess(worker), AllowCrossThreadAccess(waitEvent.get())));
+        waitEvent->wait();
+    }
+
+    bool managerHasThread() const
+    {
+        return CompositorWorkerManager::instance()->m_thread;
+    }
+
+    bool managerHasIsolate() const
+    {
+        return CompositorWorkerManager::instance()->m_isolate;
+    }
+
+private:
+    void executeScriptInWorker(WorkerThread* worker, WebWaitableEvent* waitEvent)
+    {
+        WorkerScriptController* scriptController = worker->workerGlobalScope()->script();
+        ASSERT(scriptController->evaluate(ScriptSourceCode("var counter = 0; ++counter;")));
+        waitEvent->signal();
+    }
+
+    OwnPtr<DummyPageHolder> m_page;
+    RefPtr<SecurityOrigin> m_securityOrigin;
+    OwnPtr<WorkerObjectProxy> m_objectProxy;
+};
+
+TEST_F(CompositorWorkerManagerTest, Basic)
+{
+    OwnPtr<WebWaitableEvent> creationEvent = adoptPtr(Platform::current()->createWaitableEvent());
+    RefPtr<CompositorWorkerThread> compositorWorker = createCompositorWorker(creationEvent.get());
+    creationEvent->wait();
+    checkWorkerCanExecuteScript(compositorWorker.get());
+    compositorWorker->terminateAndWait();
+}
+
+// Tests that the same WebThread is used for new workers if the WebThread is still alive.
+TEST_F(CompositorWorkerManagerTest, CreateSecondAndTerminateFirst)
+{
+    // Create the first worker and wait until it is initialized.
+    OwnPtr<WebWaitableEvent> firstCreationEvent = adoptPtr(Platform::current()->createWaitableEvent());
+    RefPtr<CompositorWorkerThread> firstWorker = createCompositorWorker(firstCreationEvent.get());
+    WebThreadSupportingGC* firstThread = &CompositorWorkerManager::instance()->compositorWorkerThread();
+    ASSERT(firstThread);
+    firstCreationEvent->wait();
+    v8::Isolate* firstIsolate = firstWorker->isolate();
+    ASSERT(firstIsolate);
+
+    // Create the second worker and immediately destroy the first worker.
+    OwnPtr<WebWaitableEvent> secondCreationEvent = adoptPtr(Platform::current()->createWaitableEvent());
+    RefPtr<CompositorWorkerThread> secondWorker = createCompositorWorker(secondCreationEvent.get());
+    firstWorker->terminateAndWait();
+
+    // Wait until the second worker is initialized. Verify that the second worker is using the same
+    // thread and Isolate as the first worker.
+    WebThreadSupportingGC* secondThread = &CompositorWorkerManager::instance()->compositorWorkerThread();
+    ASSERT(secondThread);
+    secondCreationEvent->wait();
+    EXPECT_EQ(firstThread, secondThread);
+
+    v8::Isolate* secondIsolate = secondWorker->isolate();
+    ASSERT(secondIsolate);
+    EXPECT_EQ(firstIsolate, secondIsolate);
+
+    // Verify that the worker can still successfully execute script.
+    checkWorkerCanExecuteScript(secondWorker.get());
+
+    secondWorker->terminateAndWait();
+}
+
+static void checkCurrentIsolate(v8::Isolate* isolate, WebWaitableEvent* event)
+{
+    EXPECT_EQ(v8::Isolate::GetCurrent(), isolate);
+    event->signal();
+}
+
+// Tests that a new WebThread is created if all existing workers are terminated before a new worker is created.
+TEST_F(CompositorWorkerManagerTest, TerminateFirstAndCreateSecond)
+{
+    // Create the first worker, wait until it is initialized, and terminate it.
+    OwnPtr<WebWaitableEvent> creationEvent = adoptPtr(Platform::current()->createWaitableEvent());
+    RefPtr<CompositorWorkerThread> compositorWorker = createCompositorWorker(creationEvent.get());
+    WebThreadSupportingGC* firstThread = &CompositorWorkerManager::instance()->compositorWorkerThread();
+    creationEvent->wait();
+    ASSERT(compositorWorker->isolate());
+    compositorWorker->terminateAndWait();
+
+    // Create the second worker. Verify that the second worker lives in a different WebThread since the first
+    // thread will have been destroyed after destroying the first worker.
+    creationEvent = adoptPtr(Platform::current()->createWaitableEvent());
+    compositorWorker = createCompositorWorker(creationEvent.get());
+    WebThreadSupportingGC* secondThread = &CompositorWorkerManager::instance()->compositorWorkerThread();
+    EXPECT_NE(firstThread, secondThread);
+    creationEvent->wait();
+
+    // Jump over to the worker's thread to verify that the Isolate is set up correctly and execute script.
+    OwnPtr<WebWaitableEvent> checkEvent = adoptPtr(Platform::current()->createWaitableEvent());
+    secondThread->platformThread().postTask(FROM_HERE, threadSafeBind(&checkCurrentIsolate, AllowCrossThreadAccess(compositorWorker->isolate()), AllowCrossThreadAccess(checkEvent.get())));
+    checkEvent->wait();
+    checkWorkerCanExecuteScript(compositorWorker.get());
+
+    compositorWorker->terminateAndWait();
+}
+
+// Tests that v8::Isolate and WebThread are correctly set-up if a worker is created while another is terminating.
+TEST_F(CompositorWorkerManagerTest, CreatingSecondDuringTerminationOfFirst)
+{
+    OwnPtr<WebWaitableEvent> firstCreationEvent = adoptPtr(Platform::current()->createWaitableEvent());
+    RefPtr<TestCompositorWorkerThread> firstWorker = createCompositorWorker(firstCreationEvent.get());
+    firstCreationEvent->wait();
+    v8::Isolate* firstIsolate = firstWorker->isolate();
+    ASSERT(firstIsolate);
+
+    // Request termination of the first worker, and set-up to make sure the second worker is created right as
+    // the first worker terminates its isolate.
+    OwnPtr<WebWaitableEvent> secondCreationEvent = adoptPtr(Platform::current()->createWaitableEvent());
+    RefPtr<CompositorWorkerThread> secondWorker;
+    firstWorker->setCallbackAfterV8Termination(bind(&CompositorWorkerManagerTest::createWorkerAdapter, this, &secondWorker, secondCreationEvent.get()));
+    firstWorker->terminateAndWait();
+    ASSERT(secondWorker);
+
+    secondCreationEvent->wait();
+    v8::Isolate* secondIsolate = secondWorker->isolate();
+    ASSERT(secondIsolate);
+    EXPECT_EQ(firstIsolate, secondIsolate);
+
+    // Verify that the isolate can run some scripts correctly in the second worker.
+    checkWorkerCanExecuteScript(secondWorker.get());
+    secondWorker->terminateAndWait();
+}
+
+} // namespace blink