src/hotspot/share/gc/z/zRelocationSetSelector.hpp

/*
 * Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * 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
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#ifndef SHARE_GC_Z_ZRELOCATIONSETSELECTOR_HPP
#define SHARE_GC_Z_ZRELOCATIONSETSELECTOR_HPP

#include "gc/z/zArray.hpp"
#include "memory/allocation.hpp"

class ZPage;
class ZRelocationSet;

class ZRelocationSetSelectorGroup {
private:
  const char* const    _name;
  const size_t         _page_size;
  const size_t         _object_size_limit;
  const size_t         _fragmentation_limit;

  ZArray<const ZPage*> _registered_pages;
  const ZPage**        _sorted_pages;
  size_t               _nselected;
  size_t               _relocating;
  size_t               _fragmentation;

  void semi_sort();

public:
  ZRelocationSetSelectorGroup(const char* name,
                              size_t page_size,
                              size_t object_size_limit);
  ~ZRelocationSetSelectorGroup();

  void register_live_page(const ZPage* page, size_t garbage);
  void select();

  const ZPage* const* selected() const;
  size_t nselected() const;
  size_t relocating() const;
  size_t fragmentation() const;
};

class ZRelocationSetSelector : public StackObj {
private:
  ZRelocationSetSelectorGroup _small;
  ZRelocationSetSelectorGroup _medium;
  size_t                      _live;
  size_t                      _garbage;
  size_t                      _fragmentation;

public:
  ZRelocationSetSelector();

  void register_live_page(const ZPage* page);
  void register_garbage_page(const ZPage* page);
  void select(ZRelocationSet* relocation_set);

  size_t live() const;
  size_t garbage() const;
  size_t relocating() const;
  size_t fragmentation() const;
};

#endif // SHARE_GC_Z_ZRELOCATIONSETSELECTOR_HPP