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-rw-r--r--Source/JavaScriptCore/heap/BlockAllocator.cpp172
1 files changed, 0 insertions, 172 deletions
diff --git a/Source/JavaScriptCore/heap/BlockAllocator.cpp b/Source/JavaScriptCore/heap/BlockAllocator.cpp
deleted file mode 100644
index 7a7474913..000000000
--- a/Source/JavaScriptCore/heap/BlockAllocator.cpp
+++ /dev/null
@@ -1,172 +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 "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