/* * Copyright (c) 2015, 2018, 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. * */ #include "gc/g1/g1CodeBlobClosure.hpp" #include "gc/g1/g1OopClosures.hpp" #include "memory/iterator.hpp" class G1CollectedHeap; class G1ParScanThreadState; // Simple holder object for a complete set of closures used by the G1 evacuation code. template class G1SharedClosures { static bool needs_strong_processing() { // Request strong code root processing when G1MarkFromRoot is passed in during // concurrent start. return Mark == G1MarkFromRoot; } public: G1ParCopyClosure _oops; G1ParCopyClosure _oops_in_cld; // We do not need (and actually should not) collect oops from nmethods into the // optional collection set as we already automatically collect the corresponding // nmethods in the region's strong code roots set. So set G1BarrierNoOptRoots in // this closure. // If these were present there would be opportunity for multiple threads to try // to change this oop* at the same time. Since embedded oops are not necessarily // word-aligned, this could lead to word tearing during update and crashes. G1ParCopyClosure _oops_in_nmethod; G1CLDScanClosure _clds; G1CodeBlobClosure _codeblobs; G1SharedClosures(G1CollectedHeap* g1h, G1ParScanThreadState* pss, bool process_only_dirty) : _oops(g1h, pss), _oops_in_cld(g1h, pss), _oops_in_nmethod(g1h, pss), _clds(&_oops_in_cld, process_only_dirty), _codeblobs(pss->worker_id(), &_oops_in_nmethod, needs_strong_processing()) {} };