1 /*

     2  * Copyright (c) 2016, 2018, Oracle and/or its affiliates. All rights reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.

     8  *

     9  * This code is distributed in the hope that it will be useful, but WITHOUT

    10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    12  * version 2 for more details (a copy is included in the LICENSE file that

    13  * accompanied this code).

    14  *

    15  * You should have received a copy of the GNU General Public License version

    16  * 2 along with this work; if not, write to the Free Software Foundation,

    17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    18  *

    19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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

    21  * questions.

    22  */

    23 

    24 #ifndef SHARE_GC_Z_ZMARKSTACKALLOCATOR_HPP

    25 #define SHARE_GC_Z_ZMARKSTACKALLOCATOR_HPP

    26 

    27 #include "gc/z/zGlobals.hpp"

    28 #include "gc/z/zLock.hpp"

    29 #include "utilities/globalDefinitions.hpp"

    30 

    31 class ZMarkStackSpace {

    32 private:

    33   ZLock              _expand_lock;

    34   uintptr_t          _start;

    35   volatile uintptr_t _top;

    36   volatile uintptr_t _end;

    37 

    38   void expand();

    39 

    40   uintptr_t alloc_space(size_t size);

    41   uintptr_t expand_and_alloc_space(size_t size);

    42 

    43 public:

    44   ZMarkStackSpace();

    45 

    46   bool is_initialized() const;

    47 

    48   uintptr_t alloc(size_t size);

    49 };

    50 

    51 class ZMarkStackAllocator {

    52 private:

    53   ZMarkStackMagazineList _freelist ATTRIBUTE_ALIGNED(ZCacheLineSize);

    54   ZMarkStackSpace        _space    ATTRIBUTE_ALIGNED(ZCacheLineSize);

    55 

    56   void prime_freelist();

    57   ZMarkStackMagazine* create_magazine_from_space(uintptr_t addr, size_t size);

    58 

    59 public:

    60   ZMarkStackAllocator();

    61 

    62   bool is_initialized() const;

    63 

    64   ZMarkStackMagazine* alloc_magazine();

    65   void free_magazine(ZMarkStackMagazine* magazine);

    66 };

    67 

    68 #endif // SHARE_GC_Z_ZMARKSTACKALLOCATOR_HPP