heap/GCActivityCallback.cpp

   1 /*
   2  * Copyright (C) 2010 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  *
   8  * 1.  Redistributions of source code must retain the above copyright
   9  *     notice, this list of conditions and the following disclaimer.
  10  * 2.  Redistributions in binary form must reproduce the above copyright
  11  *     notice, this list of conditions and the following disclaimer in the
  12  *     documentation and/or other materials provided with the distribution.
  13  * 3.  Neither the name of Apple Inc. ("Apple") nor the names of
  14  *     its contributors may be used to endorse or promote products derived
  15  *     from this software without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
  18  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  19  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  20  * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
  21  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  22  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  23  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  24  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  */
  28
  29 #include "config.h"
  30 #include "GCActivityCallback.h"
  31
  32 #include "Heap.h"
  33 #include "JSLock.h"
  34 #include "JSObject.h"
  35 #include "VM.h"
  36
  37 #include <wtf/RetainPtr.h>
  38 #include <wtf/WTFThreadData.h>
  39
  40 #if PLATFORM(EFL)
  41 #include <wtf/MainThread.h>
  42 #endif
  43
  44 namespace JSC {
  45
  46 bool GCActivityCallback::s_shouldCreateGCTimer = true;
  47
  48 #if USE(CF) || PLATFORM(EFL)
  49
  50 const double timerSlop = 2.0; // Fudge factor to avoid performance cost of resetting timer.
  51
  52 #if USE(CF)
  53 GCActivityCallback::GCActivityCallback(Heap* heap)
  54     : GCActivityCallback(heap->vm(), CFRunLoopGetCurrent())
  55 {
  56 }
  57
  58 GCActivityCallback::GCActivityCallback(Heap* heap, CFRunLoopRef runLoop)
  59     : GCActivityCallback(heap->vm(), runLoop)
  60 {
  61 }
  62 #elif PLATFORM(EFL)
  63 GCActivityCallback::GCActivityCallback(Heap* heap)
  64     : GCActivityCallback(heap->vm(), WTF::isMainThread())
  65 {
  66 }
  67 #endif
  68
  69 void GCActivityCallback::doWork()
  70 {
  71     Heap* heap = &m_vm->heap;
  72     if (!isEnabled())
  73         return;
  74
  75     JSLockHolder locker(m_vm);
  76     if (heap->isDeferred()) {
  77         scheduleTimer(0);
  78         return;
  79     }
  80
  81     doCollection();
  82 }
  83
  84 #if USE(CF)
  85 void GCActivityCallback::scheduleTimer(double newDelay)
  86 {
  87     if (newDelay * timerSlop > m_delay)
  88         return;
  89     double delta = m_delay - newDelay;
  90     m_delay = newDelay;
  91     CFRunLoopTimerSetNextFireDate(m_timer.get(), CFRunLoopTimerGetNextFireDate(m_timer.get()) - delta);
  92 }
  93
  94 void GCActivityCallback::cancelTimer()
  95 {
  96     m_delay = s_decade;
  97     CFRunLoopTimerSetNextFireDate(m_timer.get(), CFAbsoluteTimeGetCurrent() + s_decade);
  98 }
  99 #elif PLATFORM(EFL)
 100 void GCActivityCallback::scheduleTimer(double newDelay)
 101 {
 102     if (newDelay * timerSlop > m_delay)
 103         return;
 104
 105     stop();
 106     m_delay = newDelay;
 107
 108     ASSERT(!m_timer);
 109     m_timer = add(newDelay, this);
 110 }
 111
 112 void GCActivityCallback::cancelTimer()
 113 {
 114     m_delay = s_hour;
 115     stop();
 116 }
 117 #endif
 118
 119 void GCActivityCallback::didAllocate(size_t bytes)
 120 {
 121 #if PLATFORM(EFL)
 122     if (!isEnabled())
 123         return;
 124
 125     ASSERT(WTF::isMainThread());
 126 #endif
 127
 128     // The first byte allocated in an allocation cycle will report 0 bytes to didAllocate.
 129     // We pretend it's one byte so that we don't ignore this allocation entirely.
 130     if (!bytes)
 131         bytes = 1;
 132     double bytesExpectedToReclaim = static_cast<double>(bytes) * deathRate();
 133     double newDelay = lastGCLength() / gcTimeSlice(bytesExpectedToReclaim);
 134     scheduleTimer(newDelay);
 135 }
 136
 137 void GCActivityCallback::willCollect()
 138 {
 139     cancelTimer();
 140 }
 141
 142 void GCActivityCallback::cancel()
 143 {
 144     cancelTimer();
 145 }
 146
 147 #else
 148
 149 GCActivityCallback::GCActivityCallback(Heap* heap)
 150     : GCActivityCallback(heap->vm())
 151 {
 152 }
 153
 154 void GCActivityCallback::doWork()
 155 {
 156 }
 157
 158 void GCActivityCallback::didAllocate(size_t)
 159 {
 160 }
 161
 162 void GCActivityCallback::willCollect()
 163 {
 164 }
 165
 166 void GCActivityCallback::cancel()
 167 {
 168 }
 169
 170 #endif
 171
 172 }
 173