/*
 * Copyright (c) 2015, 2019, 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_ZPAGECACHE_HPP
#define SHARE_GC_Z_ZPAGECACHE_HPP

#include "gc/z/zList.hpp"
#include "gc/z/zPage.hpp"
#include "gc/z/zValue.hpp"
#include "memory/allocation.hpp"

class ZPageCacheFlushClosure : public StackObj {
protected:
  const size_t _requested;
  size_t       _flushed;

public:
  ZPageCacheFlushClosure(size_t requested);
  size_t overflushed() const;
  virtual bool do_page(const ZPage* page) = 0;
};

class ZPageCache {
private:
  size_t                  _available;
  ZPerNUMA<ZList<ZPage> > _small;
  ZList<ZPage>            _medium;
  ZList<ZPage>            _large;

  ZPage* alloc_small_page();
  ZPage* alloc_medium_page();
  ZPage* alloc_large_page(size_t size);

  ZPage* alloc_oversized_medium_page(size_t size);
  ZPage* alloc_oversized_large_page(size_t size);
  ZPage* alloc_oversized_page(size_t size);

  void free_page_inner(ZPage* page);

  bool flush_list_inner(ZPageCacheFlushClosure* cl, ZList<ZPage>* from, ZList<ZPage>* to);
  void flush_list(ZPageCacheFlushClosure* cl, ZList<ZPage>* from, ZList<ZPage>* to);
  void flush_per_numa_lists(ZPageCacheFlushClosure* cl, ZPerNUMA<ZList<ZPage> >* from, ZList<ZPage>* to);

public:
  ZPageCache();

  size_t available() const;

  ZPage* alloc_page(uint8_t type, size_t size);
  void free_page(ZPage* page);

  void flush(ZPageCacheFlushClosure* cl, ZList<ZPage>* to);
};

#endif // SHARE_GC_Z_ZPAGECACHE_HPP