/*

 * 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

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

#ifndef SHARE_GC_Z_ZPAGEALLOCATOR_HPP

#define SHARE_GC_Z_ZPAGEALLOCATOR_HPP

#include "gc/z/zAllocationFlags.hpp"

#include "gc/z/zList.hpp"

#include "gc/z/zLock.hpp"

#include "gc/z/zPageCache.hpp"

#include "gc/z/zPhysicalMemory.hpp"

#include "gc/z/zPreMappedMemory.hpp"

#include "gc/z/zSafeDelete.hpp"

#include "gc/z/zVirtualMemory.hpp"

#include "memory/allocation.hpp"

class ZPageAllocRequest;

class ZPageAllocator {

  friend class VMStructs;

private:

  ZLock                      _lock;

  ZVirtualMemoryManager      _virtual;

  ZPhysicalMemoryManager     _physical;

  ZPageCache                 _cache;

  const size_t               _max_reserve;

  ZPreMappedMemory           _pre_mapped;

  size_t                     _used_high;

  size_t                     _used_low;

  size_t                     _used;

  size_t                     _allocated;

  ssize_t                    _reclaimed;

  ZList<ZPageAllocRequest>   _queue;

  mutable ZSafeDelete<ZPage> _safe_delete;

  static ZPage* const      gc_marker;

  void increase_used(size_t size, bool relocation);

  void decrease_used(size_t size, bool reclaimed);

  size_t max_available(bool no_reserve) const;

  size_t try_ensure_unused(size_t size, bool no_reserve);

  size_t try_ensure_unused_for_pre_mapped(size_t size);

  ZPage* create_page(uint8_t type, size_t size);

  void destroy_page(ZPage* page);

  void flush_pre_mapped();

  void flush_cache(size_t size);

  void check_out_of_memory_during_initialization();

  ZPage* alloc_page_common_inner(uint8_t type, size_t size, ZAllocationFlags flags);

  ZPage* alloc_page_common(uint8_t type, size_t size, ZAllocationFlags flags);

  ZPage* alloc_page_blocking(uint8_t type, size_t size, ZAllocationFlags flags);

  ZPage* alloc_page_nonblocking(uint8_t type, size_t size, ZAllocationFlags flags);

  void satisfy_alloc_queue();

  void detach_memory(const ZVirtualMemory& vmem, ZPhysicalMemory& pmem);

public:

  ZPageAllocator(size_t min_capacity, size_t max_capacity, size_t max_reserve);

  bool is_initialized() const;

  size_t max_capacity() const;

  size_t current_max_capacity() const;

  size_t capacity() const;

  size_t max_reserve() const;

  size_t used_high() const;

  size_t used_low() const;

  size_t used() const;

  size_t allocated() const;

  size_t reclaimed() const;

  void reset_statistics();

  ZPage* alloc_page(uint8_t type, size_t size, ZAllocationFlags flags);

  void free_page(ZPage* page, bool reclaimed);

  void enable_deferred_delete() const;

  void disable_deferred_delete() const;

  void map_page(ZPage* page);

  void unmap_all_pages();

  bool is_alloc_stalled() const;

  void check_out_of_memory();

};

#endif // SHARE_GC_Z_ZPAGEALLOCATOR_HPP