void Heap::deallocateSmallLine(std::lock_guard<StaticMutex>& lock, SmallLine* line)
{
BASSERT(!line->refCount(lock));
SmallPage* page = SmallPage::get(line);
size_t refCount = page->refCount(lock);
page->deref(lock);
switch (refCount) {
case SmallPage::lineCount: {
// First free line in the page.
m_smallPagesWithFreeLines[page->sizeClass()].push(page);
break;
}
case 1: {
// Last free line in the page.
m_smallPages.push(page);
m_scavenger.run();
break;
}
}
}
SmallPage* Heap::allocateSmallPage(std::lock_guard<StaticMutex>& lock, size_t sizeClass)
{
Vector<SmallPage*>& smallPagesWithFreeLines = m_smallPagesWithFreeLines[sizeClass];
while (smallPagesWithFreeLines.size()) {
SmallPage* page = smallPagesWithFreeLines.pop();
if (!page->refCount(lock) || page->sizeClass() != sizeClass) // Page was promoted to the pages list.
continue;
return page;
}
SmallPage* page = [this, sizeClass]() {
if (m_smallPages.size())
return m_smallPages.pop();
m_isAllocatingPages = true;
return m_vmHeap.allocateSmallPage();
}();
page->setSizeClass(sizeClass);
return page;
}