Refactor the Heap into ThreadHeap to prepare for per thread heaps

third_party/WebKit/Source/platform/WebThreadSupportingGC.cpp

 // 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.
 
 #include "platform/WebThreadSupportingGC.h"
 
 #include "platform/heap/SafePoint.h"
 #include "public/platform/WebScheduler.h"
 #include "wtf/Threading.h"
 
 namespace blink {
 
-PassOwnPtr<WebThreadSupportingGC> WebThreadSupportingGC::create(const char* name)
+PassOwnPtr<WebThreadSupportingGC> WebThreadSupportingGC::create(const char* name, ThreadState::PerThreadHeapState perThreadHeapState)
 {
-    return adoptPtr(new WebThreadSupportingGC(name, nullptr));
+    return adoptPtr(new WebThreadSupportingGC(name, nullptr, perThreadHeapState));
 }
 
-PassOwnPtr<WebThreadSupportingGC> WebThreadSupportingGC::createForThread(WebThread* thread)
+PassOwnPtr<WebThreadSupportingGC> WebThreadSupportingGC::createForThread(WebThread* thread, ThreadState::PerThreadHeapState perThreadHeapState)
 {
-    return adoptPtr(new WebThreadSupportingGC(nullptr, thread));
+    return adoptPtr(new WebThreadSupportingGC(nullptr, thread, perThreadHeapState));
 }
 
-WebThreadSupportingGC::WebThreadSupportingGC(const char* name, WebThread* thread)
+WebThreadSupportingGC::WebThreadSupportingGC(const char* name, WebThread* thread, ThreadState::PerThreadHeapState perThreadHeapState)

[haraken, 2016/01/07 08:06:21]

Can we move the parameter from the constructor to initialize()? Then
m_perThreadHeapEnabled wouldn't be needed.

     : m_thread(thread)
+    , m_perThreadHeapEnabled(perThreadHeapState == ThreadState::PerThreadHeapEnabled)
 {
 #if ENABLE(ASSERT)
     ASSERT(!name || !thread);
     // We call this regardless of whether an existing thread is given or not,
     // as it means that blink is going to run with more than one thread.
     WTF::willCreateThread();
 #endif
     if (!m_thread) {
         // If |thread| is not given, create a new one and own it.
         m_owningThread = adoptPtr(Platform::current()->createThread(name));
         m_thread = m_owningThread.get();
     }
 }
 
 WebThreadSupportingGC::~WebThreadSupportingGC()
 {
     if (ThreadState::current() && m_owningThread) {
         // WebThread's destructor blocks until all the tasks are processed.
         SafePointScope scope(BlinkGC::HeapPointersOnStack);
         m_owningThread.clear();
     }
 }
 
 void WebThreadSupportingGC::initialize()
 {
-    ThreadState::attach();
+    ThreadState::attach(m_perThreadHeapEnabled ? ThreadState::PerThreadHeapEnabled : ThreadState::PerThreadHeapDisabled);
     m_gcTaskRunner = adoptPtr(new GCTaskRunner(m_thread));
 }
 
 void WebThreadSupportingGC::shutdown()
 {
 #if defined(LEAK_SANITIZER)
     ThreadState::current()->releaseStaticPersistentNodes();
 #endif
     // Ensure no posted tasks will run from this point on.
     m_gcTaskRunner.clear();
 
     // Shutdown the thread (via its scheduler) only when the thread is created
     // and is owned by this instance.
     if (m_owningThread)
         m_owningThread->scheduler()->shutdown();
 
     ThreadState::detach();
 }
 
 } // namespace blink