1/*
2 * Copyright (c) 1997, 2019, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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7 * published by the Free Software Foundation.
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24
25#ifndef SHARE_RUNTIME_THREADLOCALSTORAGE_HPP
26#define SHARE_RUNTIME_THREADLOCALSTORAGE_HPP
27
28#include "memory/allocation.hpp"
29
30// forward-decl as we can't have an include cycle
31class Thread;
32
33// Wrapper class for library-based (as opposed to compiler-based)
34// thread-local storage (TLS). All platforms require this for
35// signal-handler based TLS access (which while not strictly async-signal
36// safe in theory, is and has-been for a long time, in practice).
37// Platforms without compiler-based TLS (i.e. __thread storage-class modifier)
38// will use this implementation for all TLS access - see thread.hpp/cpp
39
40class ThreadLocalStorage : AllStatic {
41
42 // Exported API
43 public:
44 static Thread* thread(); // return current thread, if attached
45 static void set_thread(Thread* thread); // set current thread
46 static void init();
47 static bool is_initialized(); // can't use TLS prior to initialization
48};
49
50#endif // SHARE_RUNTIME_THREADLOCALSTORAGE_HPP
51