a060be188d
Co-authored-by: Markus Gronlund <markus.gronlund@oracle.com> Reviewed-by: coleenp, ihse, erikj, dsamersoff, mseledtsov, egahlin, mgronlun
75 lines
2.0 KiB
C++
75 lines
2.0 KiB
C++
/*
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* Copyright (c) 2014, 2018, Oracle and/or its affiliates. All rights reserved.
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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* This code is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License version 2 only, as
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* published by the Free Software Foundation.
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*
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* This code is distributed in the hope that it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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* version 2 for more details (a copy is included in the LICENSE file that
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* accompanied this code).
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*
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* You should have received a copy of the GNU General Public License version
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* 2 along with this work; if not, write to the Free Software Foundation,
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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*
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* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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* or visit www.oracle.com if you need additional information or have any
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* questions.
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*
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*/
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#ifndef SHARE_VM_JFR_UTILITIES_JFRTRYLOCK_HPP
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#define SHARE_VM_JFR_UTILITIES_JFRTRYLOCK_HPP
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#include "runtime/atomic.hpp"
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#include "runtime/orderAccess.hpp"
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#include "runtime/mutexLocker.hpp"
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#include "utilities/debug.hpp"
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class JfrTryLock {
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private:
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volatile int* const _lock;
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bool _has_lock;
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public:
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JfrTryLock(volatile int* lock) : _lock(lock), _has_lock(Atomic::cmpxchg(1, lock, 0) == 0) {}
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~JfrTryLock() {
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if (_has_lock) {
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OrderAccess::fence();
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*_lock = 0;
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}
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}
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bool has_lock() const {
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return _has_lock;
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}
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};
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class JfrMonitorTryLock : public StackObj {
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private:
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Monitor* _lock;
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bool _acquired;
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public:
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JfrMonitorTryLock(Monitor* lock) : _lock(lock), _acquired(lock->try_lock()) {}
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~JfrMonitorTryLock() {
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if (_acquired) {
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assert(_lock->owned_by_self(), "invariant");
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_lock->unlock();
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}
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}
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bool acquired() const {
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return _acquired;
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}
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};
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#endif // SHARE_VM_JFR_UTILITIES_JFRTRYLOCK_HPP
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