/*

 * Copyright (c) 2018, 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 "gc/shared/workgroup.hpp"

#include "gc/z/zRuntimeWorkers.hpp"

#include "gc/z/zThread.hpp"

#include "runtime/mutexLocker.hpp"

class ZRuntimeWorkersInitializeTask : public AbstractGangTask {

private:

  const uint _nworkers;

  uint       _started;

  Monitor    _monitor;

public:

  ZRuntimeWorkersInitializeTask(uint nworkers) :

      AbstractGangTask("ZRuntimeWorkersInitializeTask"),

      _nworkers(nworkers),

      _started(0),

      _monitor(Monitor::leaf,

               "ZRuntimeWorkersInitialize",

               false /* allow_vm_block */,

               Monitor::_safepoint_check_never) {}

  virtual void work(uint worker_id) {

    // Register as runtime worker

    ZThread::set_runtime_worker();

    // Wait for all threads to start

    MonitorLocker ml(&_monitor, Monitor::_no_safepoint_check_flag);

    if (++_started == _nworkers) {

      // All threads started

      ml.notify_all();

    } else {

      while (_started != _nworkers) {

        ml.wait();

      }

    }

  }

};

ZRuntimeWorkers::ZRuntimeWorkers() :

    _workers("RuntimeWorker",

             nworkers(),

             false /* are_GC_task_threads */,

             false /* are_ConcurrentGC_threads */) {

  log_info(gc, init)("Runtime Workers: %u parallel", nworkers());

  // Initialize worker threads

  _workers.initialize_workers();

  _workers.update_active_workers(nworkers());

  if (_workers.active_workers() != nworkers()) {

    vm_exit_during_initialization("Failed to create ZRuntimeWorkers");

  }

  // Execute task to register threads as runtime workers. This also

  // helps reduce latency in early safepoints, which otherwise would

  // have to take on any warmup costs.

  ZRuntimeWorkersInitializeTask task(nworkers());

  _workers.run_task(&task);

}

uint ZRuntimeWorkers::nworkers() const {

  return ParallelGCThreads;

}

WorkGang* ZRuntimeWorkers::workers() {

  return &_workers;

}

void ZRuntimeWorkers::threads_do(ThreadClosure* tc) const {

  _workers.threads_do(tc);

}

void ZRuntimeWorkers::print_threads_on(outputStream* st) const {

  _workers.print_worker_threads_on(st);

}