src/hotspot/share/gc/z/zResurrection.cpp
author stefank
Mon, 25 Nov 2019 14:56:15 +0100
changeset 59253 1647ed87bf1e
parent 50525 767cdb97f103
permissions -rw-r--r--
8234010: ZGC: Change ZResurrection to use Atomic::load/store Reviewed-by: pliden, eosterlund
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/*
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 * Copyright (c) 2016, 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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#include "precompiled.hpp"
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#include "gc/z/zResurrection.hpp"
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#include "runtime/atomic.hpp"
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#include "runtime/safepoint.hpp"
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#include "utilities/debug.hpp"
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volatile bool ZResurrection::_blocked = false;
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void ZResurrection::block() {
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  assert(SafepointSynchronize::is_at_safepoint(), "Should be at safepoint");
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  _blocked = true;
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}
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void ZResurrection::unblock() {
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  // No need for anything stronger than a relaxed store here.
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  // The preceeding handshake makes sure that all non-strong
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  // oops have already been healed at this point.
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  Atomic::store(&_blocked, false);
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}