/*
* Copyright (c) 2019, 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 "precompiled.hpp"
#include "jfr/recorder/checkpoint/types/traceid/jfrTraceIdEpoch.hpp"
#include "jfr/support/jfrEpochSynchronization.hpp"
#include "runtime/interfaceSupport.hpp"
#include "runtime/thread.inline.hpp"

JfrEpochSynchronization::JfrEpochSynchronization() {
  if (JfrTraceIdEpoch::is_synchronizing()) {
    // only at a safepoint
    Thread* thread = Thread::current();
    assert(thread != NULL, "invariant");
    assert(thread->is_Java_thread(), "invariant");
    JavaThread* const jt = (JavaThread*)thread;
    assert(jt->thread_state() == _thread_in_native, "invariant");
    // use ordinary transition to have the thread block and await the new epoch
    ThreadInVMfromNative transition(jt);
  }
}