MarkedAllocator.cpp [plain text]
#include "config.h"
#include "MarkedAllocator.h"
#include "GCActivityCallback.h"
#include "Heap.h"
#include "JSGlobalData.h"
#include <wtf/CurrentTime.h>
namespace JSC {
bool MarkedAllocator::isPagedOut(double deadline)
{
unsigned itersSinceLastTimeCheck = 0;
HeapBlock* block = m_blockList.head();
while (block) {
block = block->next();
++itersSinceLastTimeCheck;
if (itersSinceLastTimeCheck >= Heap::s_timeCheckResolution) {
double currentTime = WTF::monotonicallyIncreasingTime();
if (currentTime > deadline)
return true;
itersSinceLastTimeCheck = 0;
}
}
return false;
}
inline void* MarkedAllocator::tryAllocateHelper()
{
if (!m_freeList.head) {
for (MarkedBlock*& block = m_currentBlock; block; block = static_cast<MarkedBlock*>(block->next())) {
m_freeList = block->sweep(MarkedBlock::SweepToFreeList);
if (m_freeList.head)
break;
block->didConsumeFreeList();
}
if (!m_freeList.head)
return 0;
}
MarkedBlock::FreeCell* head = m_freeList.head;
m_freeList.head = head->next;
ASSERT(head);
return head;
}
inline void* MarkedAllocator::tryAllocate()
{
m_heap->m_operationInProgress = Allocation;
void* result = tryAllocateHelper();
m_heap->m_operationInProgress = NoOperation;
return result;
}
void* MarkedAllocator::allocateSlowCase()
{
ASSERT(m_heap->globalData()->apiLock().currentThreadIsHoldingLock());
#if COLLECT_ON_EVERY_ALLOCATION
m_heap->collectAllGarbage();
ASSERT(m_heap->m_operationInProgress == NoOperation);
#endif
ASSERT(!m_freeList.head);
m_heap->didAllocate(m_freeList.bytes);
void* result = tryAllocate();
if (LIKELY(result != 0))
return result;
if (m_heap->shouldCollect()) {
m_heap->collect(Heap::DoNotSweep);
result = tryAllocate();
if (result)
return result;
}
ASSERT(!m_heap->shouldCollect());
MarkedBlock* block = allocateBlock();
ASSERT(block);
addBlock(block);
result = tryAllocate();
ASSERT(result);
return result;
}
MarkedBlock* MarkedAllocator::allocateBlock()
{
MarkedBlock* block = static_cast<MarkedBlock*>(m_heap->blockAllocator().allocate());
if (block)
block = MarkedBlock::recycle(block, m_heap, m_cellSize, m_cellsNeedDestruction);
else
block = MarkedBlock::create(m_heap, m_cellSize, m_cellsNeedDestruction);
m_markedSpace->didAddBlock(block);
return block;
}
void MarkedAllocator::addBlock(MarkedBlock* block)
{
ASSERT(!m_currentBlock);
ASSERT(!m_freeList.head);
m_blockList.append(block);
m_currentBlock = block;
m_freeList = block->sweep(MarkedBlock::SweepToFreeList);
}
void MarkedAllocator::removeBlock(MarkedBlock* block)
{
if (m_currentBlock == block)
m_currentBlock = 0;
m_blockList.remove(block);
}
}