| /* |
| * 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). |
| * |
| * See {@link MC} for an overview of the mark-compact algorithm.<p> |
| * |
| * @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 |
| */ |
| |
| /** |
| * Allocate memory for an object. This class handles the default allocator |
| * from the mark sweep space, and delegates everything else to the |
| * superclass. |
| * |
| * @param bytes The number of bytes required for the object. |
| * @param align Required alignment for the object. |
| * @param offset Offset associated with the alignment. |
| * @param allocator The allocator associated with this request. |
| * @param site Allocation site |
| * @return The low address of the allocated memory. |
| */ |
| @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); |
| } |
| |
| /** |
| * Perform post-allocation actions. Initialize the object header for |
| * objects in the mark-sweep space, and delegate to the superclass for |
| * other objects. |
| * |
| * @param ref The newly allocated object |
| * @param typeRef the type reference for the instance being created |
| * @param bytes The size of the space to be allocated (in bytes) |
| * @param allocator The allocator number to be used for this allocation |
| */ |
| @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); |
| } |
| |
| /** |
| * Return the allocator instance associated with a space |
| * <code>space</code>, for this plan instance. |
| * |
| * @param space The space for which the allocator instance is desired. |
| * @return The allocator instance associated with this plan instance |
| * which is allocating into <code>space</code>, or <code>null</code> |
| * if no appropriate allocator can be established. |
| */ |
| @Override |
| public Allocator getAllocatorFromSpace(Space space) { |
| if (space == MC.mcSpace) return mc; |
| return super.getAllocatorFromSpace(space); |
| } |
| |
| |
| /**************************************************************************** |
| * |
| * Collection |
| */ |
| |
| /** |
| * Perform a per-mutator collection phase. |
| * |
| * @param phaseId The collection phase to perform |
| * @param primary Perform any single-threaded activities using this thread. |
| */ |
| @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. |
| * |
| * @see org.mmtk.plan.MutatorContext#flush() |
| */ |
| @Override |
| public void flush() { |
| super.flush(); |
| mc.flush(); |
| } |
| |
| |
| |
| } |