/*
* This file is part of the Jikes RVM project (http://jikesrvm.org).
*
* This file is licensed to You under the Eclipse Public License (EPL);
* You may not use this file except in compliance with the License. You
* may obtain a copy of the License at
*
* http://www.opensource.org/licenses/eclipse-1.0.php
*
* See the COPYRIGHT.txt file distributed with this work for information
* regarding copyright ownership.
*/
package org.mmtk.plan.markcompact;
import org.mmtk.plan.StopTheWorldMutator;
import org.mmtk.policy.MarkCompactLocal;
import org.mmtk.policy.Space;
import org.mmtk.utility.alloc.Allocator;
import org.vmmagic.pragma.*;
import org.vmmagic.unboxed.*;
/**
* This class implements <i>per-mutator thread</i> behavior
* and state for the <i>MC</i> plan, which implements a full-heap
* mark-compact collector.<p>
*
* Specifically, this class defines <i>MC</i> mutator-time allocation
* and per-mutator thread collection semantics (flushing and restoring
* per-mutator allocator state).<p>
*
* See {@link MC} for an overview of the mark-compact algorithm.
*
* @see MC
* @see MCCollector
* @see org.mmtk.plan.StopTheWorldMutator
* @see org.mmtk.plan.MutatorContext
*/
@Uninterruptible public class MCMutator extends StopTheWorldMutator {
/****************************************************************************
* Instance fields
*/
private final MarkCompactLocal mc;
/****************************************************************************
*
* Initialization
*/
/**
* Constructor
*/
public MCMutator() {
mc = new MarkCompactLocal(MC.mcSpace);
}
/****************************************************************************
*
* Mutator-time allocation
*/
/**
* {@inheritDoc}<p>
*
* This class handles the default allocator from the mark sweep space,
* and delegates everything else to the superclass.
*/
@Override
@Inline
public Address alloc(int bytes, int align, int offset, int allocator, int site) {
if (allocator == MC.ALLOC_DEFAULT) {
return mc.alloc(bytes, align, offset);
}
return super.alloc(bytes, align, offset, allocator, site);
}
/**
* {@inheritDoc}<p>
*
* Initialize the object header for objects in the mark-sweep space,
* and delegate to the superclass for other objects.
*/
@Override
@Inline
public void postAlloc(ObjectReference ref, ObjectReference typeRef,
int bytes, int allocator) {
if (allocator == MC.ALLOC_DEFAULT)
MC.mcSpace.initializeHeader(ref);
else
super.postAlloc(ref, typeRef, bytes, allocator);
}
@Override
public Allocator getAllocatorFromSpace(Space space) {
if (space == MC.mcSpace) return mc;
return super.getAllocatorFromSpace(space);
}
/****************************************************************************
*
* Collection
*/
/**
* {@inheritDoc}
*/
@Override
@Inline
public final void collectionPhase(short phaseId, boolean primary) {
if (phaseId == MC.PREPARE) {
mc.prepare();
super.collectionPhase(phaseId, primary);
return;
}
if (phaseId == MC.RELEASE) {
super.collectionPhase(phaseId, primary);
return;
}
super.collectionPhase(phaseId, primary);
}
/**
* Flush the pages this mutator has allocated back to the global
* dirty page list, where the collectors can find them.
*/
@Override
public void flush() {
super.flush();
mc.flush();
}
}