jdk

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/*
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 * Copyright (c) 2020, 2023, 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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#include "precompiled.hpp"
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#include "runtime/safepoint.hpp"
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#include "runtime/stackWatermark.inline.hpp"
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#include "runtime/stackWatermarkSet.inline.hpp"
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#include "runtime/keepStackGCProcessed.hpp"
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KeepStackGCProcessedMark::KeepStackGCProcessedMark(JavaThread* jt) :
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  _active(true),
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  _jt(jt) {
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  finish_processing();
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  if (!Thread::current()->is_Java_thread()) {
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    assert(SafepointSynchronize::is_at_safepoint() && Thread::current()->is_VM_thread(),
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           "must be either Java thread or VM thread in a safepoint");
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    _active = false;
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    return;
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  }
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  StackWatermark* our_watermark = StackWatermarkSet::get(JavaThread::current(), StackWatermarkKind::gc);
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  if (our_watermark == nullptr) {
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    _active = false;
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    return;
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  }
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  StackWatermark* their_watermark = StackWatermarkSet::get(jt, StackWatermarkKind::gc);
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  our_watermark->push_linked_watermark(their_watermark);
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}
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KeepStackGCProcessedMark::~KeepStackGCProcessedMark() {
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  if (!_active) {
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    return;
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  }
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  StackWatermark* our_watermark = StackWatermarkSet::get(JavaThread::current(), StackWatermarkKind::gc);
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  our_watermark->pop_linked_watermark();
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}
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void KeepStackGCProcessedMark::finish_processing() {
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  StackWatermarkSet::finish_processing(_jt, nullptr /* context */, StackWatermarkKind::gc);
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}
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