runtime/TimeoutChecker.cpp

   1 /*
   2  * Copyright (C) 2008, 2009 Apple Inc. All rights reserved.
   3  * Copyright (C) 2008 Cameron Zwarich <cwzwarich@uwaterloo.ca>
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  *
   9  * 1.  Redistributions of source code must retain the above copyright
  10  *     notice, this list of conditions and the following disclaimer.
  11  * 2.  Redistributions in binary form must reproduce the above copyright
  12  *     notice, this list of conditions and the following disclaimer in the
  13  *     documentation and/or other materials provided with the distribution.
  14  * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
  15  *     its contributors may be used to endorse or promote products derived
  16  *     from this software without specific prior written permission.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
  19  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  20  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  21  * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
  22  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  23  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  24  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  25  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28  */
  29
  30 #include "config.h"
  31 #include "TimeoutChecker.h"
  32
  33 #include "CallFrame.h"
  34 #include "JSGlobalObject.h"
  35
  36 #if OS(DARWIN)
  37 #include <mach/mach.h>
  38 #elif OS(WINDOWS)
  39 #include <windows.h>
  40 #else
  41 #include "CurrentTime.h"
  42 #endif
  43
  44 #if PLATFORM(BREWMP)
  45 #include <AEEStdLib.h>
  46 #endif
  47
  48 using namespace std;
  49
  50 namespace JSC {
  51
  52 // Number of ticks before the first timeout check is done.
  53 static const int ticksUntilFirstCheck = 1024;
  54
  55 // Number of milliseconds between each timeout check.
  56 static const int intervalBetweenChecks = 1000;
  57
  58 // Returns the time the current thread has spent executing, in milliseconds.
  59 static inline unsigned getCPUTime()
  60 {
  61 #if OS(DARWIN)
  62     mach_msg_type_number_t infoCount = THREAD_BASIC_INFO_COUNT;
  63     thread_basic_info_data_t info;
  64
  65     // Get thread information
  66     mach_port_t threadPort = mach_thread_self();
  67     thread_info(threadPort, THREAD_BASIC_INFO, reinterpret_cast<thread_info_t>(&info), &infoCount);
  68     mach_port_deallocate(mach_task_self(), threadPort);
  69
  70     unsigned time = info.user_time.seconds * 1000 + info.user_time.microseconds / 1000;
  71     time += info.system_time.seconds * 1000 + info.system_time.microseconds / 1000;
  72
  73     return time;
  74 #elif OS(WINDOWS)
  75     union {
  76         FILETIME fileTime;
  77         unsigned long long fileTimeAsLong;
  78     } userTime, kernelTime;
  79
  80     // GetThreadTimes won't accept NULL arguments so we pass these even though
  81     // they're not used.
  82     FILETIME creationTime, exitTime;
  83
  84     GetThreadTimes(GetCurrentThread(), &creationTime, &exitTime, &kernelTime.fileTime, &userTime.fileTime);
  85
  86     return userTime.fileTimeAsLong / 10000 + kernelTime.fileTimeAsLong / 10000;
  87 #elif PLATFORM(BREWMP)
  88     // This function returns a continuously and linearly increasing millisecond
  89     // timer from the time the device was powered on.
  90     // There is only one thread in BREW, so this is enough.
  91     return GETUPTIMEMS();
  92 #else
  93     // FIXME: We should return the time the current thread has spent executing.
  94     return currentTime() * 1000;
  95 #endif
  96 }
  97
  98 TimeoutChecker::TimeoutChecker()
  99     : m_timeoutInterval(0)
 100     , m_startCount(0)
 101 {
 102     reset();
 103 }
 104
 105 void TimeoutChecker::reset()
 106 {
 107     m_ticksUntilNextCheck = ticksUntilFirstCheck;
 108     m_timeAtLastCheck = 0;
 109     m_timeExecuting = 0;
 110 }
 111
 112 bool TimeoutChecker::didTimeOut(ExecState* exec)
 113 {
 114     unsigned currentTime = getCPUTime();
 115
 116     if (!m_timeAtLastCheck) {
 117         // Suspicious amount of looping in a script -- start timing it
 118         m_timeAtLastCheck = currentTime;
 119         return false;
 120     }
 121
 122     unsigned timeDiff = currentTime - m_timeAtLastCheck;
 123
 124     if (timeDiff == 0)
 125         timeDiff = 1;
 126
 127     m_timeExecuting += timeDiff;
 128     m_timeAtLastCheck = currentTime;
 129
 130     // Adjust the tick threshold so we get the next checkTimeout call in the
 131     // interval specified in intervalBetweenChecks.
 132     m_ticksUntilNextCheck = static_cast<unsigned>((static_cast<float>(intervalBetweenChecks) / timeDiff) * m_ticksUntilNextCheck);
 133     // If the new threshold is 0 reset it to the default threshold. This can happen if the timeDiff is higher than the
 134     // preferred script check time interval.
 135     if (m_ticksUntilNextCheck == 0)
 136         m_ticksUntilNextCheck = ticksUntilFirstCheck;
 137
 138     if (exec->dynamicGlobalObject()->shouldInterruptScriptBeforeTimeout())
 139         return true;
 140
 141     if (m_timeoutInterval && m_timeExecuting > m_timeoutInterval) {
 142         if (exec->dynamicGlobalObject()->shouldInterruptScript())
 143             return true;
 144
 145         reset();
 146     }
 147
 148     return false;
 149 }
 150
 151 } // namespace JSC