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

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
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 * 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).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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#ifndef SHARE_GC_Z_ZUNMAPPER_HPP
#define SHARE_GC_Z_ZUNMAPPER_HPP

#include "gc/z/zList.hpp"
#include "gc/z/zLock.hpp"
#include "gc/z/zThread.hpp"

class ZPage;
class ZPageAllocator;

class ZUnmapper : public ZThread {
private:
  ZPageAllocator* const _page_allocator;
  ZConditionLock        _lock;
  ZList<ZPage>          _queue;
  size_t                _enqueued_bytes;
  bool                  _warned_sync_unmapping;
  bool                  _stop;

  ZPage* dequeue();
  bool try_enqueue(ZPage* page);
  size_t queue_capacity() const;
  bool is_saturated() const;
  void do_unmap_and_destroy_page(ZPage* page) const;

protected:
  virtual void run_thread();
  virtual void terminate();

public:
  ZUnmapper(ZPageAllocator* page_allocator);

  void unmap_and_destroy_page(ZPage* page);
};

#endif // SHARE_GC_Z_ZUNMAPPER_HPP