1/* 2 * Copyright (C) 2005, 2006, 2007 Apple Inc. All rights reserved. 3 * (C) 2007 Graham Dennis (graham.dennis@gmail.com) 4 * (C) 2007 Eric Seidel <eric@webkit.org> 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of 16 * its contributors may be used to endorse or promote products derived 17 * from this software without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY 20 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 21 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 22 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY 23 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 24 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 25 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 26 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31#include "config.h" 32#include "JavaScriptThreading.h" 33 34#include <CoreFoundation/CoreFoundation.h> 35#include <JavaScriptCore/JavaScriptCore.h> 36#include <pthread.h> 37#include <wtf/Assertions.h> 38#include <wtf/HashSet.h> 39 40static JSContextGroupRef javaScriptThreadsGroup; 41 42static pthread_mutex_t javaScriptThreadsMutex = PTHREAD_MUTEX_INITIALIZER; 43static bool javaScriptThreadsShouldTerminate; 44 45static const int javaScriptThreadsCount = 4; 46 47typedef HashSet<pthread_t> ThreadSet; 48 49static ThreadSet* javaScriptThreads() 50{ 51 ASSERT(pthread_mutex_trylock(&javaScriptThreadsMutex) == EBUSY); 52 static ThreadSet staticJavaScriptThreads; 53 return &staticJavaScriptThreads; 54} 55 56// This function exercises JSC in a loop until javaScriptThreadsShouldTerminate 57// becomes true or it probabilistically decides to spawn a replacement thread and exit. 58void* runJavaScriptThread(void* arg) 59{ 60 static const char* const script = 61 "var array = [];" 62 "for (var i = 0; i < 1024; i++) {" 63 " array.push(String(i));" 64 "}"; 65 66 pthread_mutex_lock(&javaScriptThreadsMutex); 67 JSGlobalContextRef ctx = JSGlobalContextCreateInGroup(javaScriptThreadsGroup, 0); 68 pthread_mutex_unlock(&javaScriptThreadsMutex); 69 70 pthread_mutex_lock(&javaScriptThreadsMutex); 71 JSStringRef scriptRef = JSStringCreateWithUTF8CString(script); 72 pthread_mutex_unlock(&javaScriptThreadsMutex); 73 74 while (1) { 75 pthread_mutex_lock(&javaScriptThreadsMutex); 76 JSValueRef exception = 0; 77 JSEvaluateScript(ctx, scriptRef, 0, 0, 1, &exception); 78 ASSERT(!exception); 79 pthread_mutex_unlock(&javaScriptThreadsMutex); 80 81 pthread_mutex_lock(&javaScriptThreadsMutex); 82 size_t valuesCount = 1024; 83 JSValueRef values[valuesCount]; 84 for (size_t i = 0; i < valuesCount; ++i) 85 values[i] = JSObjectMake(ctx, 0, 0); 86 pthread_mutex_unlock(&javaScriptThreadsMutex); 87 88 // Check for cancellation. 89 if (javaScriptThreadsShouldTerminate) 90 goto done; 91 92 // Respawn probabilistically. 93 if (random() % 5 == 0) { 94 pthread_mutex_lock(&javaScriptThreadsMutex); 95 pthread_t pthread; 96 pthread_create(&pthread, 0, &runJavaScriptThread, 0); 97 pthread_detach(pthread); 98 javaScriptThreads()->add(pthread); 99 pthread_mutex_unlock(&javaScriptThreadsMutex); 100 goto done; 101 } 102 } 103 104done: 105 pthread_mutex_lock(&javaScriptThreadsMutex); 106 JSStringRelease(scriptRef); 107 JSGarbageCollect(ctx); 108 JSGlobalContextRelease(ctx); 109 javaScriptThreads()->remove(pthread_self()); 110 pthread_mutex_unlock(&javaScriptThreadsMutex); 111 return 0; 112} 113 114void startJavaScriptThreads() 115{ 116 javaScriptThreadsGroup = JSContextGroupCreate(); 117 118 pthread_mutex_lock(&javaScriptThreadsMutex); 119 120 for (int i = 0; i < javaScriptThreadsCount; i++) { 121 pthread_t pthread; 122 pthread_create(&pthread, 0, &runJavaScriptThread, 0); 123 pthread_detach(pthread); 124 javaScriptThreads()->add(pthread); 125 } 126 127 pthread_mutex_unlock(&javaScriptThreadsMutex); 128} 129 130void stopJavaScriptThreads() 131{ 132 pthread_mutex_lock(&javaScriptThreadsMutex); 133 134 javaScriptThreadsShouldTerminate = true; 135 136 pthread_mutex_unlock(&javaScriptThreadsMutex); 137 138 while (true) { 139 pthread_mutex_lock(&javaScriptThreadsMutex); 140 int threadCount = javaScriptThreads()->size(); 141 pthread_mutex_unlock(&javaScriptThreadsMutex); 142 143 if (!threadCount) 144 break; 145 146 usleep(1000); 147 } 148} 149