webkitgtk-2.4.11webkitgtk-2.4.11

1 files changed, 191 insertions, 0 deletions

diff --git a/Source/JavaScriptCore/runtime/GCActivityCallback.cpp b/Source/JavaScriptCore/runtime/GCActivityCallback.cpp
new file mode 100644
index 000000000..e1cc98867
--- /dev/null
+++ b/Source/JavaScriptCore/runtime/GCActivityCallback.cpp
@@ -0,0 +1,191 @@
+/*
+ * Copyright (C) 2010 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. 
+ * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
+ *     its contributors may be used to endorse or promote products derived
+ *     from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "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 OR ITS 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 "GCActivityCallback.h"
+
+#include "APIShims.h"
+#include "Heap.h"
+#include "VM.h"
+#include "JSLock.h"
+#include "JSObject.h"
+
+#include <wtf/RetainPtr.h>
+#include <wtf/WTFThreadData.h>
+
+#if PLATFORM(EFL)
+#include <wtf/MainThread.h>
+#endif
+
+namespace JSC {
+
+bool GCActivityCallback::s_shouldCreateGCTimer = true;
+
+#if USE(CF) || PLATFORM(EFL)
+
+const double gcTimeSlicePerMB = 0.01; // Percentage of CPU time we will spend to reclaim 1 MB
+const double maxGCTimeSlice = 0.05; // The maximum amount of CPU time we want to use for opportunistic timer-triggered collections.
+const double timerSlop = 2.0; // Fudge factor to avoid performance cost of resetting timer.
+
+#if !PLATFORM(IOS)
+const double pagingTimeOut = 0.1; // Time in seconds to allow opportunistic timer to iterate over all blocks to see if the Heap is paged out.
+#endif
+
+#if !USE(CF)
+const double hour = 60 * 60;
+#endif
+
+#if USE(CF)
+DefaultGCActivityCallback::DefaultGCActivityCallback(Heap* heap)
+    : GCActivityCallback(heap->vm(), CFRunLoopGetCurrent())
+    , m_delay(s_decade)
+{
+}
+
+DefaultGCActivityCallback::DefaultGCActivityCallback(Heap* heap, CFRunLoopRef runLoop)
+    : GCActivityCallback(heap->vm(), runLoop)
+    , m_delay(s_decade)
+{
+}
+#elif PLATFORM(EFL)
+DefaultGCActivityCallback::DefaultGCActivityCallback(Heap* heap)
+    : GCActivityCallback(heap->vm(), WTF::isMainThread())
+    , m_delay(hour)
+{
+}
+#endif
+
+void DefaultGCActivityCallback::doWork()
+{
+    Heap* heap = &m_vm->heap;
+    if (!isEnabled())
+        return;
+    
+    APIEntryShim shim(m_vm);
+#if !PLATFORM(IOS)
+    double startTime = WTF::monotonicallyIncreasingTime();
+    if (heap->isPagedOut(startTime + pagingTimeOut)) {
+        heap->activityCallback()->cancel();
+        heap->increaseLastGCLength(pagingTimeOut);
+        return;
+    }
+#endif
+    heap->collect();
+}
+    
+#if USE(CF)
+void DefaultGCActivityCallback::scheduleTimer(double newDelay)
+{
+    if (newDelay * timerSlop > m_delay)
+        return;
+    double delta = m_delay - newDelay;
+    m_delay = newDelay;
+    CFRunLoopTimerSetNextFireDate(m_timer.get(), CFRunLoopTimerGetNextFireDate(m_timer.get()) - delta);
+}
+
+void DefaultGCActivityCallback::cancelTimer()
+{
+    m_delay = s_decade;
+    CFRunLoopTimerSetNextFireDate(m_timer.get(), CFAbsoluteTimeGetCurrent() + s_decade);
+}
+#elif PLATFORM(EFL)
+void DefaultGCActivityCallback::scheduleTimer(double newDelay)
+{
+    if (newDelay * timerSlop > m_delay)
+        return;
+
+    stop();
+    m_delay = newDelay;
+    
+    ASSERT(!m_timer);
+    m_timer = add(newDelay, this);
+}
+
+void DefaultGCActivityCallback::cancelTimer()
+{
+    m_delay = hour;
+    stop();
+}
+#endif
+
+void DefaultGCActivityCallback::didAllocate(size_t bytes)
+{
+#if PLATFORM(EFL)
+    if (!isEnabled())
+        return;
+
+    ASSERT(WTF::isMainThread());
+#endif
+
+    // The first byte allocated in an allocation cycle will report 0 bytes to didAllocate. 
+    // We pretend it's one byte so that we don't ignore this allocation entirely.
+    if (!bytes)
+        bytes = 1;
+    Heap* heap = static_cast<Heap*>(&m_vm->heap);
+    double gcTimeSlice = std::min((static_cast<double>(bytes) / MB) * gcTimeSlicePerMB, maxGCTimeSlice);
+    double newDelay = heap->lastGCLength() / gcTimeSlice;
+    scheduleTimer(newDelay);
+}
+
+void DefaultGCActivityCallback::willCollect()
+{
+    cancelTimer();
+}
+
+void DefaultGCActivityCallback::cancel()
+{
+    cancelTimer();
+}
+
+#else
+
+DefaultGCActivityCallback::DefaultGCActivityCallback(Heap* heap)
+    : GCActivityCallback(heap->vm())
+{
+}
+
+void DefaultGCActivityCallback::doWork()
+{
+}
+
+void DefaultGCActivityCallback::didAllocate(size_t)
+{
+}
+
+void DefaultGCActivityCallback::willCollect()
+{
+}
+
+void DefaultGCActivityCallback::cancel()
+{
+}
+
+#endif
+
+}
+