src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/gc/shenandoah/ShenandoahHeapRegion.java
author rkennke
Mon, 10 Dec 2018 15:47:44 +0100
changeset 52925 9c18c9d839d3
child 54388 a1acc800c87a
permissions -rw-r--r--
8214259: Implementation: JEP 189: Shenandoah: A Low-Pause-Time Garbage Collector (Experimental) Reviewed-by: kvn, roland, shade, coleenp, lmesnik, pliden, jgeorge, ihse, erikj Contributed-by: Christine Flood <chf@redhat.com>, Aleksey Shipilev <shade@redhat.com>, Roland Westrelin <rwestrel@redhat.com>, Zhenygu Gu <zgu@redhat.com>, Andrew Haley <aph@redhat.com>, Andrew Dinn <adinn@redhat.com>, Mario Torre <mtorre@redhat.com>, Roman Kennke <rkennke@redhat.com>

/*
 * Copyright (c) 2017, 2018, Red Hat, Inc. All rights reserved.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 *
 */

package sun.jvm.hotspot.gc.shenandoah;

import sun.jvm.hotspot.gc.shared.ContiguousSpace;
import sun.jvm.hotspot.types.CIntegerField;
import sun.jvm.hotspot.runtime.VM;
import sun.jvm.hotspot.types.Type;
import sun.jvm.hotspot.types.TypeDataBase;
import sun.jvm.hotspot.debugger.Address;

import java.util.Observable;
import java.util.Observer;


public class ShenandoahHeapRegion extends ContiguousSpace {
    private static CIntegerField RegionSizeBytes;
    static {
        VM.registerVMInitializedObserver(new Observer() {
            public void update(Observable o, Object data) {
                initialize(VM.getVM().getTypeDataBase());
            }
        });
    }

    static private synchronized void initialize(TypeDataBase db) {
        Type type = db.lookupType("ShenandoahHeapRegion");
        RegionSizeBytes = type.getCIntegerField("RegionSizeBytes");
    }

    public static long regionSizeBytes() { return RegionSizeBytes.getValue(); }

    public ShenandoahHeapRegion(Address addr) {
        super(addr);
    }
}