1/*
2 * Copyright (c) 2014, 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_GC_SHARED_GCID_HPP
26#define SHARE_GC_SHARED_GCID_HPP
27
28#include "memory/allocation.hpp"
29
30class GCId : public AllStatic {
31private:
32 friend class GCIdMark;
33
34 static uint _next_id;
35 static const uint UNDEFINED = (uint)-1;
36 static uint create();
37
38public:
39 // Returns the currently active GC id. Asserts that there is an active GC id.
40 static uint current();
41 // Same as current() but can return undefined() if no GC id is currently active
42 static uint current_or_undefined();
43 // Returns the next expected GCId.
44 static uint peek();
45 static uint undefined() { return UNDEFINED; }
46 static size_t print_prefix(char* buf, size_t len);
47};
48
49class GCIdMark : public StackObj {
50private:
51 const uint _previous_gc_id;
52
53public:
54 GCIdMark();
55 GCIdMark(uint gc_id);
56 ~GCIdMark();
57};
58
59#endif // SHARE_GC_SHARED_GCID_HPP
60