ReleaseSpanToPageCache()

void Spices::PageCache::ReleaseSpanToPageCache

(

scl::span *

s

)

Release span from cc to pc,.

Parameters

[in]

s

span.

Release to system.

Merge to left.

Merge to right.

Push span to list.

Release to system.

Merge to left.

Merge to right.

Push span to list.

Definition at line 43 of file PageCache.cpp.

    {
        std::unique_lock<std::mutex> lock(m_Mutex);
 
        if (s->m_NPages > MemoryPool::PAGE_NUM - 1)
        {
            void* ptr = reinterpret_cast<void*>(s->m_PageId << MemoryPool::PAGE_SHIFT);
            SystemFree(ptr);
 
            m_IdSpanMap.set(s->m_PageId, nullptr);
            m_SpanPool.Delete(s);
            
            return;
        }
 
        for(;;)
        {
            const size_t leftId = s->m_PageId - 1;
 
            scl::span* leftSpan = static_cast<scl::span*>(m_IdSpanMap.get(leftId));
 
            if (!leftSpan)
            {
                break;
            }
 
            if (leftSpan->m_IsUse)
            {
                break;
            }
 
            if (leftSpan->m_NPages + s->m_NPages > MemoryPool::PAGE_NUM - 1)
            {
                break;
            }
 
            s->m_PageId  = leftSpan->m_PageId;
            s->m_NPages += leftSpan->m_NPages;
 
            m_SpanLists[leftSpan->m_NPages].Erase(leftSpan);
            m_SpanPool.Delete(leftSpan);
        }
 
        for (;;)
        {
            const size_t rightId = s->m_PageId + s->m_NPages;
 
            scl::span* rightSpan = static_cast<scl::span*>(m_IdSpanMap.get(rightId));
 
            if (!rightSpan)
            {
                break;
            }
 
            if (rightSpan->m_IsUse)
            {
                break;
            }
 
            if (rightSpan->m_NPages + s->m_NPages > MemoryPool::PAGE_NUM - 1)
            {
                break;
            }
 
            s->m_NPages += rightSpan->m_NPages;
 
            m_SpanLists[rightSpan->m_NPages].Erase(rightSpan);
            m_SpanPool.Delete(rightSpan);
        }
 
        m_SpanLists[s->m_NPages].PushFront(s);
        s->m_IsUse = false;
 
        m_IdSpanMap.set(s->m_PageId, s);
        m_IdSpanMap.set(s->m_PageId + s->m_NPages - 1, s);
    }

References scl::span::m_IsUse, and Spices::SystemFree().

Referenced by Spices::MemoryPool::Free(), and Spices::CentralCache::ReleaseListToSpans().