Mercurial > hg > graal-jvmci-8
view src/share/vm/gc_implementation/shared/suspendibleThreadSet.hpp @ 20762:c2844108a708
Merge
author | asaha |
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date | Thu, 23 Oct 2014 12:02:08 -0700 |
parents | 581e70386ec9 |
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/* * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. * */ #ifndef SHARE_VM_GC_IMPLEMENTATION_SHARED_SUSPENDIBLETHREADSET_HPP #define SHARE_VM_GC_IMPLEMENTATION_SHARED_SUSPENDIBLETHREADSET_HPP #include "memory/allocation.hpp" // A SuspendibleThreadSet is a set of threads that can be suspended. // A thread can join and later leave the set, and periodically yield. // If some thread (not in the set) requests, via synchronize(), that // the threads be suspended, then the requesting thread is blocked // until all the threads in the set have yielded or left the set. Threads // may not enter the set when an attempted suspension is in progress. The // suspending thread later calls desynchronize(), allowing the suspended // threads to continue. class SuspendibleThreadSet : public AllStatic { private: static uint _nthreads; static uint _nthreads_stopped; static bool _suspend_all; static double _suspend_all_start; public: // Add the current thread to the set. May block if a suspension is in progress. static void join(); // Removes the current thread from the set. static void leave(); // Returns true if an suspension is in progress. static bool should_yield() { return _suspend_all; } // Suspends the current thread if a suspension is in progress. static void yield(); // Returns when all threads in the set are suspended. static void synchronize(); // Resumes all suspended threads in the set. static void desynchronize(); }; class SuspendibleThreadSetJoiner : public StackObj { public: SuspendibleThreadSetJoiner() { SuspendibleThreadSet::join(); } ~SuspendibleThreadSetJoiner() { SuspendibleThreadSet::leave(); } bool should_yield() { return SuspendibleThreadSet::should_yield(); } void yield() { SuspendibleThreadSet::yield(); } }; #endif // SHARE_VM_GC_IMPLEMENTATION_SHARED_SUSPENDIBLETHREADSET_HPP