1/*
2 * Copyright (c) 2012, 2019, 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
25#ifndef SHARE_MEMORY_METASPACE_METABASE_HPP
26#define SHARE_MEMORY_METASPACE_METABASE_HPP
27
28#include "utilities/globalDefinitions.hpp"
29
30namespace metaspace {
31
32// Super class of Metablock and Metachunk to allow them to
33// be put on the FreeList and in the BinaryTreeDictionary.
34template <class T>
35class Metabase {
36 size_t _word_size;
37 T* _next;
38 T* _prev;
39
40 protected:
41 Metabase(size_t word_size) : _word_size(word_size), _next(NULL), _prev(NULL) {}
42
43 public:
44 T* next() const { return _next; }
45 T* prev() const { return _prev; }
46 void set_next(T* v) { _next = v; assert(v != this, "Boom");}
47 void set_prev(T* v) { _prev = v; assert(v != this, "Boom");}
48 void clear_next() { set_next(NULL); }
49 void clear_prev() { set_prev(NULL); }
50
51 size_t size() const volatile { return _word_size; }
52 void set_size(size_t v) { _word_size = v; }
53
54 void link_next(T* ptr) { set_next(ptr); }
55 void link_prev(T* ptr) { set_prev(ptr); }
56 void link_after(T* ptr) {
57 link_next(ptr);
58 if (ptr != NULL) ptr->link_prev((T*)this);
59 }
60
61 uintptr_t* end() const { return ((uintptr_t*) this) + size(); }
62
63 bool cantCoalesce() const { return false; }
64
65 // Debug support
66#ifdef ASSERT
67 void* prev_addr() const { return (void*)&_prev; }
68 void* next_addr() const { return (void*)&_next; }
69 void* size_addr() const { return (void*)&_word_size; }
70#endif
71 bool verify_chunk_in_free_list(T* tc) const { return true; }
72 bool verify_par_locked() { return true; }
73
74 void assert_is_mangled() const {/* Don't check "\*/}
75
76 bool is_free() { return true; }
77};
78
79} // namespace metaspace
80
81#endif // SHARE_MEMORY_METASPACE_METABASE_HPP
82