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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.def; |
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|
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import org.jnode.vm.Unsafe; |
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import org.jnode.vm.scheduler.Monitor; |
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|
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/** |
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* @author Ewout Prangsma (epr@users.sourceforge.net) |
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*/ |
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final class GCThread extends Thread { |
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|
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/** |
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* The manager |
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*/ |
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private final GCManager manager; |
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|
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/** |
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* Monitor for synchronizing access to my fields |
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*/ |
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private final Monitor heapMonitor; |
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|
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/** |
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* Is a GC run requested? |
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*/ |
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private boolean runNeeded; |
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|
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/** |
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* Is the GC currently active |
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*/ |
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private boolean gcActive; |
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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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*/ |
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public GCThread(GCManager manager, Monitor heapMonitor) { |
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super("gc-thread"); |
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this.manager = manager; |
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this.heapMonitor = heapMonitor; |
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} |
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|
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/** |
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* Trigger a GC run. |
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* |
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* @param waitToFinish If true, block until the run is ready, if false, return |
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* immediately. |
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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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heapMonitor.enter(); |
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try { |
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runNeeded = true; |
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heapMonitor.NotifyAll(); |
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if (waitToFinish) { |
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while (runNeeded || gcActive) { |
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try { |
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heapMonitor.Wait(0L); |
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} catch (InterruptedException ex) { |
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// Ignore |
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} |
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} |
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} |
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} finally { |
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heapMonitor.exit(); |
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} |
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} |
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|
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/** |
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* Continue to GC. |
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* |
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* @see java.lang.Runnable#run() |
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*/ |
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public final void run() { |
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while (true) { |
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try { |
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heapMonitor.enter(); |
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try { |
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while (!runNeeded) { |
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heapMonitor.Wait(0L); |
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} |
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gcActive = true; |
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runNeeded = false; |
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} finally { |
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heapMonitor.exit(); |
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} |
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|
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// Now do the actual GC |
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manager.gc(); |
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|
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// Notify that we're ready |
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gcActive = false; |
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heapMonitor.enter(); |
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try { |
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heapMonitor.NotifyAll(); |
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} finally { |
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heapMonitor.exit(); |
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} |
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} catch (Throwable ex) { |
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try { |
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Unsafe.debug(ex.getMessage()); |
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Unsafe.debug('\n'); |
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Unsafe.debugStackTrace(ex); |
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Unsafe.die("GCThread failed"); |
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} catch (Throwable ex2) { |
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// Ignore |
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} |
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} |
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} |
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} |
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} |
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|
