PageMemory* FreePagePool::takeFreePage(int index) {
MutexLocker locker(m_mutex[index]);
while (PoolEntry* entry = m_pool[index]) {
m_pool[index] = entry->next;
PageMemory* memory = entry->data;
ASSERT(memory);
delete entry;
if (memory->commit())
return memory;
// We got some memory, but failed to commit it, try again.
delete memory;
}
return nullptr;
}
PageMemory* PageMemory::allocate(size_t payloadSize)
{
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);
PageMemory* storage = setupPageMemoryInRegion(pageMemoryRegion, 0, payloadSize);
RELEASE_ASSERT(storage->commit());
return storage;
}