1 /*
 2  * Copyright (c) 2017, 2018, Red Hat, Inc. 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
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24 
25 #ifndef SHARE_GC_EPSILON_EPSILONBARRIERSET_HPP
26 #define SHARE_GC_EPSILON_EPSILONBARRIERSET_HPP
27 
28 #include "gc/shared/barrierSet.hpp"
29 
30 // No interaction with application is required for Epsilon, and therefore
31 // the barrier set is empty.
32 class EpsilonBarrierSet: public BarrierSet {
33   friend class VMStructs;
34 
35 public:
36   EpsilonBarrierSet();
37 
38   // Loom support
39   static constexpr bool is_concurrent_gc() { return false; }
40 
41   virtual void print_on(outputStream *st) const {}
42 
43   virtual void on_thread_create(Thread* thread);
44   virtual void on_thread_destroy(Thread* thread);
45 
46   template <DecoratorSet decorators, typename BarrierSetT = EpsilonBarrierSet>
47   class AccessBarrier: public BarrierSet::AccessBarrier<decorators, BarrierSetT> {};
48 };
49 
50 template<>
51 struct BarrierSet::GetName<EpsilonBarrierSet> {
52   static const BarrierSet::Name value = BarrierSet::EpsilonBarrierSet;
53 };
54 
55 template<>
56 struct BarrierSet::GetType<BarrierSet::EpsilonBarrierSet> {
57   typedef ::EpsilonBarrierSet type;
58 };
59 
60 #endif // SHARE_GC_EPSILON_EPSILONBARRIERSET_HPP