/*
* This file is part of the Jikes RVM project (http://jikesrvm.org).
*
* This file is licensed to You under the Common Public License (CPL);
* 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/cpl1.0.php
*
* See the COPYRIGHT.txt file distributed with this work for information
* regarding copyright ownership.
*/
package org.mmtk.policy;
import org.jikesrvm.annotations.NoSubArchCompile;
import org.mmtk.utility.alloc.LargeObjectAllocator;
import org.mmtk.utility.Treadmill;
import org.mmtk.utility.gcspy.drivers.TreadmillDriver;
import org.mmtk.utility.Constants;
import org.vmmagic.pragma.*;
import org.vmmagic.unboxed.*;
/**
* Each instance of this class is intended to provide fast,
* unsynchronized access to a treadmill. Therefore instances must not
* be shared across truely concurrent threads (CPUs). Rather, one or
* more instances of this class should be bound to each CPU. The
* shared VMResource used by each instance is the point of global
* synchronization, and synchronization only occurs at the granularity
* of aquiring (and releasing) chunks of memory from the VMResource.
*
* If there are C CPUs and T TreadmillSpaces, there must be C X T
* instances of this class, one for each CPU, TreadmillSpace pair.
*/
@Uninterruptible public final class LargeObjectLocal extends LargeObjectAllocator
implements Constants {
/****************************************************************************
*
* Class variables
*/
/****************************************************************************
*
* Instance variables
*/
/****************************************************************************
*
* Initialization
*/
/**
* Constructor
*
* @param space The treadmill space to which this thread instance is
* bound.
*/
public LargeObjectLocal(LargeObjectSpace space) {
super(space);
this.space = space;
}
/****************************************************************************
*
* Allocation
*/
/**
* This is called each time a cell is alloced (i.e. if a cell is
* reused, this will be called each time it is reused in the
* lifetime of the cell, by contrast to initializeCell, which is
* called exactly once.).
*
* @param cell The newly allocated cell
*/
@Inline
protected void postAlloc(Address cell) {
space.getTreadmill().addToTreadmill(Treadmill.payloadToNode(cell));
}
/****************************************************************************
*
* Collection
*/
/**
* Prepare for a collection. Clear the treadmill to-space head and
* prepare the collector. If paranoid, perform a sanity check.
*/
public void prepare(boolean fullHeap) {
}
/**
* Finish up after a collection.
*/
public void release(boolean fullHeap) {
}
/****************************************************************************
*
* Miscellaneous size-related methods
*/
/**
* Return the size of the per-superpage header required by this
* system. In this case it is just the underlying superpage header
* size.
*
* @return The size of the per-superpage header required by this
* system.
*/
@Inline
protected int superPageHeaderSize() {
return Treadmill.headerSize();
}
/**
* Return the size of the per-cell header for cells of a given class
* size.
*
* @return The size of the per-cell header for cells of a given class
* size.
*/
@Inline
protected int cellHeaderSize() {
return 0;
}
/**
* Gather data for GCSpy from the nursery
* @param event the gc event
* @param losDriver the GCSpy space driver
*/
@NoSubArchCompile
public void gcspyGatherData(int event, TreadmillDriver losDriver) {
// TODO: assumes single threaded
space.getTreadmill().gcspyGatherData(event, losDriver);
}
/**
* Gather data for GCSpy for an older space
* @param event the gc event
* @param losDriver the GCSpy space driver
* @param tospace gather from tospace?
*/
@NoSubArchCompile
public void gcspyGatherData(int event, TreadmillDriver losDriver, boolean tospace) {
// TODO: assumes single threaded
space.getTreadmill().gcspyGatherData(event, losDriver, tospace);
}
}