Stream scripts to V8 as they load - Blink side.

Source/bindings/core/v8/ScriptStreamerThread.h

Index: Source/bindings/core/v8/ScriptStreamerThread.h
diff --git a/Source/bindings/core/v8/ScriptStreamerThread.h b/Source/bindings/core/v8/ScriptStreamerThread.h
new file mode 100644
index 0000000000000000000000000000000000000000..5f81cdb62add57995315339a082ad5e161fc28e0
--- /dev/null
+++ b/Source/bindings/core/v8/ScriptStreamerThread.h
@@ -0,0 +1,72 @@
+// Copyright 2014 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.
+
+#ifndef ScriptStreamerThread_h
+#define ScriptStreamerThread_h
+
+#include "platform/TaskSynchronizer.h"
+#include "public/platform/WebThread.h"
+#include "wtf/OwnPtr.h"
+
+#include <v8.h>
+
+namespace blink {
+
+class ScriptStreamer;
+
+// A singleton thread for running background tasks for script streaming.
+class ScriptStreamerThread {
+public:
+    static void init();
+    static void shutdown();
+    static ScriptStreamerThread* shared();
+
+    void postTask(WebThread::Task*);
+
+    bool isRunningTask() const
+    {
+        return m_runningTask;
+    }
+
+    static void taskDone(void*)
+    {
+        shared()->m_runningTask = false;

[haraken, 2014/09/10 05:57:51]

Shall we add ASSERT(shared()->m_runningTask) before this line?

[marja, 2014/09/11 09:15:37]

Done.

+    }
+
+private:
+    ScriptStreamerThread()
+        : m_runningTask(false) { }
+
+    bool isRunning()
+    {
+        return !!m_thread;
+    }
+
+    void markAsCompleted(TaskSynchronizer* taskSynchronizer)
+    {
+        taskSynchronizer->taskCompleted();
+    }
+
+    blink::WebThread& platformThread();
+
+    // At the moment, we only use one thread, so we can only stream one script
+    // at a time. FIXME: Use a thread pool and stream multiple scripts.
+    WTF::OwnPtr<blink::WebThread> m_thread;
+    bool m_runningTask;
+};
+
+class ScriptStreamingTask : public WebThread::Task {
+public:
+    ScriptStreamingTask(v8::ScriptCompiler::ScriptStreamingTask*, ScriptStreamer*);
+    virtual void run() OVERRIDE;
+
+private:
+    WTF::OwnPtr<v8::ScriptCompiler::ScriptStreamingTask> m_v8Task;
+    ScriptStreamer* m_streamer;

[haraken, 2014/09/10 05:57:51]

Doesn't this need to be a RefPtr?

[marja, 2014/09/11 09:15:37]

No, the code is correct as is, afaics (see the manual ref() & deref() in
ScriptStreamer.cpp for keeping ScriptStreamer alive long enough).

And I cannot use RefPtrs on a background thread anyway. If I put a RefPtr here,
I cannot access it on the background thread: not in run() and not in dtor either
(the dtor is called immediately after running the task, and it's called on a
background thread), so there's no possibility to even schedule something on the
main thread that would then access the RefPtr.

+};
+
+
+} // namespace blink
+
+#endif // ScriptStreamerThread_h