/*

 * Copyright (c) 1997, 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 "precompiled.hpp"

#include "gc/shared/barrierSet.hpp"

#include "gc/shared/barrierSetAssembler.hpp"

#include "runtime/thread.hpp"

#include "utilities/macros.hpp"

BarrierSet* BarrierSet::_barrier_set = NULL;

class SetBarrierSetNonJavaThread : public ThreadClosure {

  BarrierSet* _barrier_set;

  size_t _count;

public:

  SetBarrierSetNonJavaThread(BarrierSet* barrier_set) :

    _barrier_set(barrier_set), _count(0) {}

  virtual void do_thread(Thread* thread) {

    _barrier_set->on_thread_create(thread);

    ++_count;

  }

  size_t count() const { return _count; }

};

void BarrierSet::set_barrier_set(BarrierSet* barrier_set) {

  assert(_barrier_set == NULL, "Already initialized");

  _barrier_set = barrier_set;

  // Some threads are created before the barrier set, so the call to

  // BarrierSet::on_thread_create had to be deferred for them.  Now that

  // we have the barrier set, do those deferred calls.

  // First do any non-JavaThreads.

  SetBarrierSetNonJavaThread njt_closure(_barrier_set);

  Threads::non_java_threads_do(&njt_closure);

  // Do the current (main) thread.  Ensure it's the one and only

  // JavaThread so far.  Also verify that it isn't yet on the thread

  // list, else we'd also need to call BarrierSet::on_thread_attach.

  assert(Thread::current()->is_Java_thread(),

         "Expected main thread to be a JavaThread");

  assert((njt_closure.count() + 1) == Threads::threads_before_barrier_set(),

         "Unexpected JavaThreads before barrier set initialization: "

         "Non-JavaThreads: " SIZE_FORMAT ", all: " SIZE_FORMAT,

         njt_closure.count(), Threads::threads_before_barrier_set());

  assert(!JavaThread::current()->on_thread_list(),

         "Main thread already on thread list.");

  _barrier_set->on_thread_create(Thread::current());

}

// Called from init.cpp

void gc_barrier_stubs_init() {

  BarrierSet* bs = BarrierSet::barrier_set();

#ifndef ZERO

  BarrierSetAssembler* bs_assembler = bs->barrier_set_assembler();

  bs_assembler->barrier_stubs_init();

#endif

}