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     */
013    package org.mmtk.plan;
014    
015    import org.mmtk.utility.Log;
016    import org.mmtk.vm.VM;
017    
018    import org.vmmagic.pragma.*;
019    
020    /**
021     * This class (and its sub-classes) implement <i>per-mutator thread</i>
022     * behavior and state.
023     *
024     * MMTk assumes that the VM instantiates instances of MutatorContext
025     * in thread local storage (TLS) for each application thread. Accesses
026     * to this state are therefore assumed to be low-cost during mutator
027     * time.<p>
028     *
029     * @see MutatorContext
030     */
031    @Uninterruptible
032    public abstract class SimpleMutator extends MutatorContext {
033    
034      /****************************************************************************
035       *
036       * Collection.
037       */
038    
039      /**
040       * Perform a per-mutator collection phase.   This is executed by
041       * one collector thread on behalf of a mutator thread.
042       *
043       * @param phaseId The unique phase identifier
044       * @param primary Should this thread be used to execute any single-threaded
045       * local operations?
046       */
047      @Inline
048      public void collectionPhase(short phaseId, boolean primary) {
049        if (phaseId == Simple.PREPARE_STACKS) {
050          if (!Plan.stacksPrepared()) {
051            VM.collection.prepareMutator(this);
052          }
053          flushRememberedSets();
054          return;
055        }
056    
057        if (phaseId == Simple.PREPARE) {
058          los.prepare(true);
059          lgcode.prepare(true);
060          smcode.prepare();
061          nonmove.prepare();
062          VM.memory.collectorPrepareVMSpace();
063          return;
064        }
065    
066        if (phaseId == Simple.RELEASE) {
067          los.release(true);
068          lgcode.release(true);
069          smcode.release();
070          nonmove.release();
071          VM.memory.collectorReleaseVMSpace();
072          return;
073        }
074    
075        Log.write("Per-mutator phase \""); Phase.getPhase(phaseId).logPhase();
076        Log.writeln("\" not handled.");
077        VM.assertions.fail("Per-mutator phase not handled!");
078      }
079    }