Refactor the Heap into ThreadHeap to prepare for per thread heaps

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

 // Copyright 2016 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/heap/PageMemory.h"
 
 #include "platform/heap/Heap.h"
 #include "wtf/Assertions.h"
 #include "wtf/PageAllocator.h"
 
@@ skipping 10 matching lines @@
     return WTF::setSystemPagesAccessible(m_base, m_size);
 }
 
 void MemoryRegion::decommit()
 {
     WTF::decommitSystemPages(m_base, m_size);
     WTF::setSystemPagesInaccessible(m_base, m_size);
 }
 
 
-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();
 }
 
 // TODO(haraken): Like partitionOutOfMemoryWithLotsOfUncommitedPages(),
 // we should probably have a way to distinguish physical memory OOM from
 // virtual address space OOM.
 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)
 {
     RegionTree* current = this;
     while (current) {
         Address base = current->m_region->base();
         if (address < base) {
             current = current->m_left;
             continue;
@@ skipping 65 matching lines @@
     // Setup the payload one guard page into the page memory.
     Address payloadAddress = region->base() + pageOffset + blinkGuardPageSize;
     return new PageMemory(region, MemoryRegion(payloadAddress, payloadSize));
 }
 
 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);
 
     // Virtual memory allocation routines operate in OS page sizes.
     // Round up the requested size to nearest os page size.
     payloadSize = roundToOsPageSize(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;
 }
 
 } // namespace blink