Refactor the Heap into ThreadHeap to prepare for per thread heaps

third_party/WebKit/Source/platform/heap/PageMemory.cpp

Index: third_party/WebKit/Source/platform/heap/PageMemory.cpp
diff --git a/third_party/WebKit/Source/platform/heap/PageMemory.cpp b/third_party/WebKit/Source/platform/heap/PageMemory.cpp
index 5efe1fcede7eb3036afbf20179a5dcfb76e7911d..ac2ca841c254cbc6f78d2516080ca4bbae41f095 100644
--- a/third_party/WebKit/Source/platform/heap/PageMemory.cpp
+++ b/third_party/WebKit/Source/platform/heap/PageMemory.cpp
@@ -28,19 +28,20 @@ void MemoryRegion::decommit()
 }
 
 
-PageMemoryRegion::PageMemoryRegion(Address base, size_t size, unsigned numPages)
+PageMemoryRegion::PageMemoryRegion(Address base, size_t size, unsigned numPages, Heap* heap)
     : MemoryRegion(base, size)
     , m_isLargePage(numPages == 1)
     , m_numPages(numPages)
+    , m_heap(heap)
 {
-    Heap::addPageMemoryRegion(this);
+    m_heap->addPageMemoryRegion(this);
     for (size_t i = 0; i < blinkPagesPerRegion; ++i)
         m_inUse[i] = false;
 }
 
 PageMemoryRegion::~PageMemoryRegion()
 {
-    Heap::removePageMemoryRegion(this);
+    m_heap->removePageMemoryRegion(this);
     release();
 }
 
@@ -52,14 +53,14 @@ static NEVER_INLINE void blinkGCOutOfMemory()
     IMMEDIATE_CRASH();
 }
 
-PageMemoryRegion* PageMemoryRegion::allocate(size_t size, unsigned numPages)
+PageMemoryRegion* PageMemoryRegion::allocate(size_t size, unsigned numPages, Heap* heap)
 {
     // Round size up to the allocation granularity.
     size = (size + WTF::kPageAllocationGranularityOffsetMask) & WTF::kPageAllocationGranularityBaseMask;
     Address base = static_cast<Address>(WTF::allocPages(nullptr, size, blinkPageSize, WTF::PageInaccessible));
     if (!base)
         blinkGCOutOfMemory();
-    return new PageMemoryRegion(base, size, numPages);
+    return new PageMemoryRegion(base, size, numPages, heap);
 }
 
 PageMemoryRegion* RegionTree::lookup(Address address)
@@ -145,7 +146,7 @@ static size_t roundToOsPageSize(size_t size)
     return (size + WTF::kSystemPageSize - 1) & ~(WTF::kSystemPageSize - 1);
 }
 
-PageMemory* PageMemory::allocate(size_t payloadSize)
+PageMemory* PageMemory::allocate(size_t payloadSize, Heap* heap)
 {
     ASSERT(payloadSize > 0);
 
@@ -156,7 +157,7 @@ PageMemory* PageMemory::allocate(size_t payloadSize)
     // Overallocate by 2 times OS page size to have space for a
     // guard page at the beginning and end of blink heap page.
     size_t allocationSize = payloadSize + 2 * blinkGuardPageSize;
-    PageMemoryRegion* pageMemoryRegion = PageMemoryRegion::allocateLargePage(allocationSize);
+    PageMemoryRegion* pageMemoryRegion = PageMemoryRegion::allocateLargePage(allocationSize, heap);

[haraken, 2016/02/29 11:17:45]

A better fix would be to call heap->addPageMemoryRegion(pageMemoryRegion) here.

Then you can remove PageMemoryRegion::m_heap. (I don't think PageMemoryRegion
needs to know the heap.)

[keishi, 2016/03/02 06:01:03]

We need to call removePageMemoryRegion from ~PageMemoryRegion so I don't think I
can remove PageMemoryRegion::m_heap.

[haraken, 2016/03/02 07:21:07]

~PageMemoryRegion is called only by 'delete current' in RegionTree::remove. Can
you move m_heap->removePageMemoryRegion(this) into RegionTree::remove? The
RegionTree::remove can take the heap parameter.

(Nit: Ideally, those RegionTree methods should be members of the Heap class.
Heap::addToRegionTree(), Heap::removeFromRegionTree() etc, which accesses
Heap::m_regionTree.)

[keishi, 2016/03/02 10:19:31]

Done.

     PageMemory* storage = setupPageMemoryInRegion(pageMemoryRegion, 0, payloadSize);
     RELEASE_ASSERT(storage->commit());
     return storage;