001/*
002 *  This file is part of the Jikes RVM project (http://jikesrvm.org).
003 *
004 *  This file is licensed to You under the Eclipse Public License (EPL);
005 *  You may not use this file except in compliance with the License. You
006 *  may obtain a copy of the License at
007 *
008 *      http://www.opensource.org/licenses/eclipse-1.0.php
009 *
010 *  See the COPYRIGHT.txt file distributed with this work for information
011 *  regarding copyright ownership.
012 */
013package org.mmtk.plan.concurrent.marksweep;
014
015import org.mmtk.plan.concurrent.ConcurrentConstraints;
016import org.mmtk.policy.MarkSweepSpace;
017import org.mmtk.policy.SegregatedFreeListSpace;
018
019import org.vmmagic.pragma.*;
020
021/**
022 * This class and its subclasses communicate to the host VM/Runtime
023 * any features of the selected plan that it needs to know.  This is
024 * separate from the main Plan/PlanLocal class in order to bypass any
025 * issues with ordering of static initialization.
026 */
027@Uninterruptible
028public class CMSConstraints extends ConcurrentConstraints {
029  @Override
030  public int gcHeaderBits() {
031    return MarkSweepSpace.LOCAL_GC_BITS_REQUIRED;
032  }
033
034  @Override
035  public int gcHeaderWords() {
036    return MarkSweepSpace.GC_HEADER_WORDS_REQUIRED;
037  }
038
039  @Override
040  public int maxNonLOSDefaultAllocBytes() {
041    return SegregatedFreeListSpace.MAX_FREELIST_OBJECT_BYTES;
042  }
043}