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/* |
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* $Id$ |
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* |
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* Copyright (C) 2003-2009 JNode.org |
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* |
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* This library is free software; you can redistribute it and/or modify it |
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* under the terms of the GNU Lesser General Public License as published |
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* by the Free Software Foundation; either version 2.1 of the License, or |
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* (at your option) any later version. |
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* |
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* This library is distributed in the hope that it will be useful, but |
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* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY |
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* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public |
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* License for more details. |
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* |
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* You should have received a copy of the GNU Lesser General Public License |
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* along with this library; If not, write to the Free Software Foundation, Inc., |
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* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
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*/ |
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|
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package org.jnode.vm.memmgr.generational; |
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|
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import org.jnode.vm.scheduler.Monitor; |
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|
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/** |
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* @author Loic Rouchon (loic.rouchon@insa-lyon.fr) |
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*/ |
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final class GenGCSweepThread extends Thread { |
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|
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/** |
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* The queue that contains references to objects to free |
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*/ |
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private final GenGCManager gcManager; |
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|
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private final Monitor heapMonitor; |
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|
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private Monitor monitor = new Monitor(); |
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|
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private boolean runNeeded = false; |
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|
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/** |
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* Initialize this instance. |
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* |
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* @param manager |
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* The queue that contains references to objects to free |
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* @param defaultHeap |
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* The default heap that contains objects to free |
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*/ |
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public GenGCSweepThread(GenGCManager gcManager, Monitor heapMonitor) { |
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super("gc-sweep-thread"); |
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this.gcManager = gcManager; |
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this.heapMonitor = heapMonitor; |
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} |
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|
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/** |
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* |
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* @param waitToFinish |
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*/ |
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public final void trigger(boolean waitToFinish) { |
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if (runNeeded && !waitToFinish) { |
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return; |
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} |
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monitor.enter(); |
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if (!runNeeded) { |
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startThread(); |
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} |
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if (waitToFinish) { |
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waitForEnd(); |
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} |
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monitor.exit(); |
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} |
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|
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/** |
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* Wait for objects to delete and when available, free them. |
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* |
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* @see java.lang.Runnable#run() |
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*/ |
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@Override |
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public final void run() { |
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// Unsafe.debug("GenGCSweepThread.run()\n"); |
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while (true) { |
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waitForTrigger(); |
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// Unsafe.debug("GenGCSweepThread.run(sweep)\n"); |
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gcManager.sweep(); |
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heapMonitor.enter(); |
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gcManager.cleanup(); |
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heapMonitor.exit(); |
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notifyEnds(); |
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} |
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} |
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|
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private void startThread() { |
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runNeeded = true; |
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monitor.NotifyAll(); |
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// Unsafe.debug("GenGCSweepThread.startThread()\n"); |
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} |
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|
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private void waitForEnd() { |
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// Unsafe.debug("GenGCSweepThread.waitForEnd()\n"); |
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while (runNeeded) { |
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waitForMonitor(); |
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} |
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// Unsafe.debug("GenGCSweepThread.waitForEnd(done)\n"); |
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} |
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|
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private void waitForTrigger() { |
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// Unsafe.debug("GenGCSweepThread.run(wait)\n"); |
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monitor.enter(); |
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while (!runNeeded) { |
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waitForMonitor(); |
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} |
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} |
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|
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private void notifyEnds() { |
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// Unsafe.debug("GenGCSweepThread.run(ended)\n"); |
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runNeeded = false; |
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monitor.NotifyAll(); |
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monitor.exit(); |
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} |
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|
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private void waitForMonitor() { |
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try { |
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monitor.Wait(0L); |
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} catch (InterruptedException e) { |
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} |
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} |
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} |
