src/share/vm/runtime/threadCritical.hpp

Thu, 21 Nov 2013 12:30:35 -0800

author
kvn
date
Thu, 21 Nov 2013 12:30:35 -0800
changeset 6485
da862781b584
parent 2314
f95d63e2154a
child 6876
710a3c8b516e
permissions
-rw-r--r--

Merge

duke@435 1 /*
stefank@2314 2 * Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved.
duke@435 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@435 4 *
duke@435 5 * This code is free software; you can redistribute it and/or modify it
duke@435 6 * under the terms of the GNU General Public License version 2 only, as
duke@435 7 * published by the Free Software Foundation.
duke@435 8 *
duke@435 9 * This code is distributed in the hope that it will be useful, but WITHOUT
duke@435 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@435 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
duke@435 12 * version 2 for more details (a copy is included in the LICENSE file that
duke@435 13 * accompanied this code).
duke@435 14 *
duke@435 15 * You should have received a copy of the GNU General Public License version
duke@435 16 * 2 along with this work; if not, write to the Free Software Foundation,
duke@435 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@435 18 *
trims@1907 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
trims@1907 20 * or visit www.oracle.com if you need additional information or have any
trims@1907 21 * questions.
duke@435 22 *
duke@435 23 */
duke@435 24
stefank@2314 25 #ifndef SHARE_VM_RUNTIME_THREADCRITICAL_HPP
stefank@2314 26 #define SHARE_VM_RUNTIME_THREADCRITICAL_HPP
stefank@2314 27
stefank@2314 28 #include "memory/allocation.hpp"
stefank@2314 29
duke@435 30 // ThreadCritical is used to protect short non-blocking critical sections.
duke@435 31 // This class must use no vm facilities that require initialization.
duke@435 32 // It is used very early in the vm's initialization, in allocation
duke@435 33 // code and other areas. ThreadCritical regions are reentrant.
duke@435 34 //
duke@435 35 // Due to race conditions during vm exit, some of the os level
duke@435 36 // synchronization primitives may not be deallocated at exit. It
twisti@1040 37 // is a good plan to implement the platform dependent sections of
duke@435 38 // code with resources that are recoverable during process
duke@435 39 // cleanup by the os. Calling the initialize method before use
duke@435 40 // is also problematic, it is best to use preinitialized primitives
duke@435 41 // if possible. As an example:
duke@435 42 //
duke@435 43 // mutex_t mp = DEFAULTMUTEX;
duke@435 44 //
duke@435 45 // Also note that this class is declared as a StackObj to enforce
duke@435 46 // block structured short locks. It cannot be declared a ResourceObj
duke@435 47 // or CHeapObj, due to initialization issues.
duke@435 48
duke@435 49 class ThreadCritical : public StackObj {
duke@435 50 friend class os;
duke@435 51 private:
duke@435 52 static void initialize();
duke@435 53 static void release();
duke@435 54
duke@435 55 public:
duke@435 56 ThreadCritical();
duke@435 57 ~ThreadCritical();
duke@435 58 };
stefank@2314 59
stefank@2314 60 #endif // SHARE_VM_RUNTIME_THREADCRITICAL_HPP

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