| /* |
| * Copyright (C) 2012-2019 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. ``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 |
| * 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 "IncrementalSweeper.h" |
| |
| #include "Heap.h" |
| #include "JSObject.h" |
| #include "JSString.h" |
| #include "MarkedBlock.h" |
| #include "JSCInlines.h" |
| |
| namespace JSC { |
| |
| static constexpr Seconds sweepTimeSlice = 10_ms; |
| static constexpr double sweepTimeTotal = .10; |
| static constexpr double sweepTimeMultiplier = 1.0 / sweepTimeTotal; |
| |
| void IncrementalSweeper::scheduleTimer() |
| { |
| setTimeUntilFire(sweepTimeSlice * sweepTimeMultiplier); |
| } |
| |
| IncrementalSweeper::IncrementalSweeper(Heap* heap) |
| : Base(heap->vm()) |
| , m_currentDirectory(nullptr) |
| { |
| } |
| |
| void IncrementalSweeper::doWork(VM& vm) |
| { |
| doSweep(vm, MonotonicTime::now()); |
| } |
| |
| void IncrementalSweeper::doSweep(VM& vm, MonotonicTime sweepBeginTime) |
| { |
| while (sweepNextBlock(vm)) { |
| Seconds elapsedTime = MonotonicTime::now() - sweepBeginTime; |
| if (elapsedTime < sweepTimeSlice) |
| continue; |
| |
| scheduleTimer(); |
| return; |
| } |
| |
| if (m_shouldFreeFastMallocMemoryAfterSweeping) { |
| WTF::releaseFastMallocFreeMemory(); |
| m_shouldFreeFastMallocMemoryAfterSweeping = false; |
| } |
| cancelTimer(); |
| } |
| |
| bool IncrementalSweeper::sweepNextBlock(VM& vm) |
| { |
| vm.heap.stopIfNecessary(); |
| |
| MarkedBlock::Handle* block = nullptr; |
| |
| for (; m_currentDirectory; m_currentDirectory = m_currentDirectory->nextDirectory()) { |
| block = m_currentDirectory->findBlockToSweep(); |
| if (block) |
| break; |
| } |
| |
| if (block) { |
| DeferGCForAWhile deferGC(vm.heap); |
| block->sweep(nullptr); |
| vm.heap.objectSpace().freeOrShrinkBlock(block); |
| return true; |
| } |
| |
| return vm.heap.sweepNextLogicallyEmptyWeakBlock(); |
| } |
| |
| void IncrementalSweeper::startSweeping(Heap& heap) |
| { |
| scheduleTimer(); |
| m_currentDirectory = heap.objectSpace().firstDirectory(); |
| } |
| |
| void IncrementalSweeper::stopSweeping() |
| { |
| m_currentDirectory = nullptr; |
| cancelTimer(); |
| } |
| |
| } // namespace JSC |