1/* 2 * Copyright (C) 2011, 2014 Apple Inc. All Rights Reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY 14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR 17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY 21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26#include "config.h" 27#include "MemoryPressureHandler.h" 28 29#include "CSSValuePool.h" 30#include "Document.h" 31#include "Font.h" 32#include "FontCache.h" 33#include "GCController.h" 34#include "JSDOMWindow.h" 35#include "MemoryCache.h" 36#include "Page.h" 37#include "PageCache.h" 38#include "ScrollingThread.h" 39#include "StorageThread.h" 40#include "WorkerThread.h" 41#include <wtf/CurrentTime.h> 42#include <wtf/FastMalloc.h> 43#include <wtf/Functional.h> 44#include <wtf/StdLibExtras.h> 45 46namespace WebCore { 47 48bool MemoryPressureHandler::ReliefLogger::s_loggingEnabled = false; 49 50MemoryPressureHandler& memoryPressureHandler() 51{ 52 DEPRECATED_DEFINE_STATIC_LOCAL(MemoryPressureHandler, staticMemoryPressureHandler, ()); 53 return staticMemoryPressureHandler; 54} 55 56MemoryPressureHandler::MemoryPressureHandler() 57 : m_installed(false) 58 , m_lastRespondTime(0) 59 , m_lowMemoryHandler(releaseMemory) 60 , m_underMemoryPressure(false) 61#if PLATFORM(IOS) 62 // FIXME: Can we share more of this with OpenSource? 63 , m_memoryPressureReason(MemoryPressureReasonNone) 64 , m_clearPressureOnMemoryRelease(true) 65 , m_releaseMemoryBlock(0) 66 , m_observer(0) 67#endif 68{ 69} 70 71void MemoryPressureHandler::releaseNoncriticalMemory() 72{ 73 { 74 ReliefLogger log("Purge inactive FontData"); 75 fontCache().purgeInactiveFontData(); 76 } 77 78 { 79 ReliefLogger log("Clear WidthCaches"); 80 clearWidthCaches(); 81 } 82 83 { 84 ReliefLogger log("Discard Selector Query Cache"); 85 for (auto* document : Document::allDocuments()) 86 document->clearSelectorQueryCache(); 87 } 88 89 { 90 ReliefLogger log("Clearing JS string cache"); 91 JSDOMWindow::commonVM().stringCache.clear(); 92 } 93} 94 95void MemoryPressureHandler::releaseCriticalMemory() 96{ 97 { 98 ReliefLogger log("Empty the PageCache"); 99 int savedPageCacheCapacity = pageCache()->capacity(); 100 pageCache()->setCapacity(0); 101 pageCache()->setCapacity(savedPageCacheCapacity); 102 } 103 104 { 105 ReliefLogger log("Prune MemoryCache"); 106 memoryCache()->pruneToPercentage(0); 107 } 108 109 { 110 ReliefLogger log("Drain CSSValuePool"); 111 cssValuePool().drain(); 112 } 113 114 { 115 ReliefLogger log("Discard StyleResolvers"); 116 for (auto* document : Document::allDocuments()) 117 document->clearStyleResolver(); 118 } 119 120 { 121 ReliefLogger log("Discard all JIT-compiled code"); 122 gcController().discardAllCompiledCode(); 123 } 124} 125 126void MemoryPressureHandler::releaseMemory(bool critical) 127{ 128 releaseNoncriticalMemory(); 129 130 if (critical) 131 releaseCriticalMemory(); 132 133 platformReleaseMemory(critical); 134 135 { 136 ReliefLogger log("Release free FastMalloc memory"); 137 // FastMalloc has lock-free thread specific caches that can only be cleared from the thread itself. 138 StorageThread::releaseFastMallocFreeMemoryInAllThreads(); 139 WorkerThread::releaseFastMallocFreeMemoryInAllThreads(); 140#if ENABLE(ASYNC_SCROLLING) && !PLATFORM(IOS) 141 ScrollingThread::dispatch(bind(WTF::releaseFastMallocFreeMemory)); 142#endif 143 WTF::releaseFastMallocFreeMemory(); 144 } 145} 146 147#if !PLATFORM(COCOA) 148void MemoryPressureHandler::install() { } 149void MemoryPressureHandler::uninstall() { } 150void MemoryPressureHandler::holdOff(unsigned) { } 151void MemoryPressureHandler::respondToMemoryPressure(bool) { } 152void MemoryPressureHandler::platformReleaseMemory(bool) { } 153void MemoryPressureHandler::ReliefLogger::platformLog() { } 154size_t MemoryPressureHandler::ReliefLogger::platformMemoryUsage() { return 0; } 155#endif 156 157} // namespace WebCore 158