JavaScriptCore-7601.1.46.3.tar.gz

[apple/javascriptcore.git] / heap / BlockAllocator.cpp

diff --git a/heap/BlockAllocator.cpp b/heap/BlockAllocator.cpp
deleted file mode 100644 (file)
index bf408f8..0000000
--- a/heap/BlockAllocator.cpp
+++ /dev/null
@@ -1,173 +0,0 @@
-/*
- * Copyright (C) 2012 Apple Inc. All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
- * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
- * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
- * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
- * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
- * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
- * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
- * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
- * THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#include "config.h"
-#include "BlockAllocator.h"
-
-#include "CopiedBlock.h"
-#include "CopyWorkList.h"
-#include "MarkedBlock.h"
-#include "JSCInlines.h"
-#include "WeakBlock.h"
-#include <wtf/CurrentTime.h>
-
-namespace JSC {
-
-inline ThreadIdentifier createBlockFreeingThread(BlockAllocator* allocator)
-{
-    if (!GCActivityCallback::s_shouldCreateGCTimer)
-        return 0; // No block freeing thread.
-    ThreadIdentifier identifier = createThread(allocator->blockFreeingThreadStartFunc, allocator, "JavaScriptCore::BlockFree");
-    RELEASE_ASSERT(identifier);
-    return identifier;
-}
-
-BlockAllocator::BlockAllocator()
-    : m_superRegion()
-    , m_copiedRegionSet(CopiedBlock::blockSize)
-    , m_markedRegionSet(MarkedBlock::blockSize)
-    , m_fourKBBlockRegionSet(WeakBlock::blockSize)
-    , m_workListRegionSet(CopyWorkListSegment::blockSize)
-    , m_numberOfEmptyRegions(0)
-    , m_isCurrentlyAllocating(false)
-    , m_blockFreeingThreadShouldQuit(false)
-    , m_blockFreeingThread(createBlockFreeingThread(this))
-{
-    m_regionLock.Init();
-}
-
-BlockAllocator::~BlockAllocator()
-{
-    releaseFreeRegions();
-    {
-        std::lock_guard<std::mutex> lock(m_emptyRegionConditionMutex);
-        m_blockFreeingThreadShouldQuit = true;
-        m_emptyRegionCondition.notify_all();
-    }
-    if (m_blockFreeingThread)
-        waitForThreadCompletion(m_blockFreeingThread);
-    ASSERT(allRegionSetsAreEmpty());
-    ASSERT(m_emptyRegions.isEmpty());
-}
-
-bool BlockAllocator::allRegionSetsAreEmpty() const
-{
-    return m_copiedRegionSet.isEmpty()
-        && m_markedRegionSet.isEmpty()
-        && m_fourKBBlockRegionSet.isEmpty()
-        && m_workListRegionSet.isEmpty();
-}
-
-void BlockAllocator::releaseFreeRegions()
-{
-    while (true) {
-        Region* region;
-        {
-            SpinLockHolder locker(&m_regionLock);
-            if (!m_numberOfEmptyRegions)
-                region = 0;
-            else {
-                region = m_emptyRegions.removeHead();
-                RELEASE_ASSERT(region);
-                m_numberOfEmptyRegions--;
-            }
-        }
-        
-        if (!region)
-            break;
-
-        region->destroy();
-    }
-}
-
-void BlockAllocator::waitForDuration(std::chrono::milliseconds duration)
-{
-    std::unique_lock<std::mutex> lock(m_emptyRegionConditionMutex);
-
-    // If this returns early, that's fine, so long as it doesn't do it too
-    // frequently. It would only be a bug if this function failed to return
-    // when it was asked to do so.
-    if (m_blockFreeingThreadShouldQuit)
-        return;
-
-    m_emptyRegionCondition.wait_for(lock, duration);
-}
-
-void BlockAllocator::blockFreeingThreadStartFunc(void* blockAllocator)
-{
-    static_cast<BlockAllocator*>(blockAllocator)->blockFreeingThreadMain();
-}
-
-void BlockAllocator::blockFreeingThreadMain()
-{
-    size_t currentNumberOfEmptyRegions;
-    while (!m_blockFreeingThreadShouldQuit) {
-        // Generally wait for one second before scavenging free blocks. This
-        // may return early, particularly when we're being asked to quit.
-        waitForDuration(std::chrono::seconds(1));
-        if (m_blockFreeingThreadShouldQuit)
-            break;
-        
-        if (m_isCurrentlyAllocating) {
-            m_isCurrentlyAllocating = false;
-            continue;
-        }
-
-        // Sleep until there is actually work to do rather than waking up every second to check.
-        {
-            std::unique_lock<std::mutex> lock(m_emptyRegionConditionMutex);
-            SpinLockHolder regionLocker(&m_regionLock);
-            while (!m_numberOfEmptyRegions && !m_blockFreeingThreadShouldQuit) {
-                m_regionLock.Unlock();
-                m_emptyRegionCondition.wait(lock);
-                m_regionLock.Lock();
-            }
-            currentNumberOfEmptyRegions = m_numberOfEmptyRegions;
-        }
-        
-        size_t desiredNumberOfEmptyRegions = currentNumberOfEmptyRegions / 2;
-        
-        while (!m_blockFreeingThreadShouldQuit) {
-            Region* region;
-            {
-                SpinLockHolder locker(&m_regionLock);
-                if (m_numberOfEmptyRegions <= desiredNumberOfEmptyRegions)
-                    region = 0;
-                else {
-                    region = m_emptyRegions.removeHead();
-                    RELEASE_ASSERT(region);
-                    m_numberOfEmptyRegions--;
-                }
-            }
-            
-            if (!region)
-                break;
-            
-            region->destroy();
-        }
-    }
-}
-
-} // namespace JSC