Mercurial > hg > graal-compiler
view src/share/vm/prims/jvmtiRawMonitor.hpp @ 3917:eca1193ca245
4965777: GC changes to support use of discovered field for pending references
Summary: If and when the reference handler thread is able to use the discovered field to link reference objects in its pending list, so will GC. In that case, GC will scan through this field once a reference object has been placed on the pending list, but not scan that field before that stage, as the field is used by the concurrent GC thread to link discovered objects. When ReferenceHandleR thread does not use the discovered field for the purpose of linking the elements in the pending list, as would be the case in older JDKs, the JVM will fall back to the old behaviour of using the next field for that purpose.
Reviewed-by: jcoomes, mchung, stefank
author | ysr |
---|---|
date | Wed, 07 Sep 2011 13:55:42 -0700 |
parents | f95d63e2154a |
children | 8b46b0196eb0 |
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/* * Copyright (c) 1999, 2010, 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_PRIMS_JVMTIRAWMONITOR_HPP #define SHARE_VM_PRIMS_JVMTIRAWMONITOR_HPP #ifndef JVMTI_KERNEL #include "runtime/objectMonitor.hpp" #include "utilities/growableArray.hpp" #endif // // class JvmtiRawMonitor // // Used by JVMTI methods: All RawMonitor methods (CreateRawMonitor, EnterRawMonitor, etc.) // // Wrapper for ObjectMonitor class that saves the Monitor's name // class JvmtiRawMonitor : public ObjectMonitor { private: int _magic; char * _name; // JVMTI_RM_MAGIC is set in contructor and unset in destructor. enum { JVMTI_RM_MAGIC = (int)(('T' << 24) | ('I' << 16) | ('R' << 8) | 'M') }; int SimpleEnter (Thread * Self) ; int SimpleExit (Thread * Self) ; int SimpleWait (Thread * Self, jlong millis) ; int SimpleNotify (Thread * Self, bool All) ; public: JvmtiRawMonitor(const char *name); ~JvmtiRawMonitor(); int raw_enter(TRAPS); int raw_exit(TRAPS); int raw_wait(jlong millis, bool interruptable, TRAPS); int raw_notify(TRAPS); int raw_notifyAll(TRAPS); int magic() { return _magic; } const char *get_name() { return _name; } bool is_valid(); }; // Onload pending raw monitors // Class is used to cache onload or onstart monitor enter // which will transition into real monitor when // VM is fully initialized. class JvmtiPendingMonitors : public AllStatic { private: static GrowableArray<JvmtiRawMonitor*> *_monitors; // Cache raw monitor enter inline static GrowableArray<JvmtiRawMonitor*>* monitors() { return _monitors; } static void dispose() { delete monitors(); } public: static void enter(JvmtiRawMonitor *monitor) { monitors()->append(monitor); } static int count() { return monitors()->length(); } static void destroy(JvmtiRawMonitor *monitor) { while (monitors()->contains(monitor)) { monitors()->remove(monitor); } } // Return false if monitor is not found in the list. static bool exit(JvmtiRawMonitor *monitor) { if (monitors()->contains(monitor)) { monitors()->remove(monitor); return true; } else { return false; } } static void transition_raw_monitors(); }; #endif // SHARE_VM_PRIMS_JVMTIRAWMONITOR_HPP