/*

 * Copyright (c) 2017, Red Hat, Inc. and/or its affiliates.

 * 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/gcArguments.hpp"

#include "gc/serial/serialArguments.hpp"

#include "runtime/globals.hpp"

#include "runtime/globals_extension.hpp"

#include "runtime/java.hpp"

#include "runtime/os.hpp"

#include "utilities/defaultStream.hpp"

#include "utilities/macros.hpp"

#if INCLUDE_ALL_GCS

#include "gc/parallel/parallelArguments.hpp"

#include "gc/cms/cmsArguments.hpp"

#include "gc/g1/g1Arguments.hpp"

#endif

GCArguments* GCArguments::_instance = NULL;

GCArguments* GCArguments::arguments() {

  assert(is_initialized(), "Heap factory not yet created");

  return _instance;

}

bool GCArguments::is_initialized() {

  return _instance != NULL;

}

bool GCArguments::gc_selected() {

#if INCLUDE_ALL_GCS

  return UseSerialGC || UseParallelGC || UseParallelOldGC || UseConcMarkSweepGC || UseG1GC;

#else

  return UseSerialGC;

#endif // INCLUDE_ALL_GCS

}

void GCArguments::select_gc() {

  if (!gc_selected()) {

    select_gc_ergonomically();

    if (!gc_selected()) {

      vm_exit_during_initialization("Garbage collector not selected (default collector explicitly disabled)", NULL);

    }

  }

}

void GCArguments::select_gc_ergonomically() {

#if INCLUDE_ALL_GCS

  if (os::is_server_class_machine()) {

    FLAG_SET_ERGO_IF_DEFAULT(bool, UseG1GC, true);

  } else {

    FLAG_SET_ERGO_IF_DEFAULT(bool, UseSerialGC, true);

  }

#else

  UNSUPPORTED_OPTION(UseG1GC);

  UNSUPPORTED_OPTION(UseParallelGC);

  UNSUPPORTED_OPTION(UseParallelOldGC);

  UNSUPPORTED_OPTION(UseConcMarkSweepGC);

  FLAG_SET_ERGO_IF_DEFAULT(bool, UseSerialGC, true);

#endif // INCLUDE_ALL_GCS

}

void GCArguments::initialize_flags() {

#if INCLUDE_ALL_GCS

  if (MinHeapFreeRatio == 100) {

    // Keeping the heap 100% free is hard ;-) so limit it to 99%.

    FLAG_SET_ERGO(uintx, MinHeapFreeRatio, 99);

  }

  // If class unloading is disabled, also disable concurrent class unloading.

  if (!ClassUnloading) {

    FLAG_SET_CMDLINE(bool, CMSClassUnloadingEnabled, false);

    FLAG_SET_CMDLINE(bool, ClassUnloadingWithConcurrentMark, false);

  }

#endif // INCLUDE_ALL_GCS

}

jint GCArguments::initialize() {

  assert(!is_initialized(), "GC arguments already initialized");

  select_gc();

#if !INCLUDE_ALL_GCS

  if (UseParallelGC || UseParallelOldGC) {

    jio_fprintf(defaultStream::error_stream(), "UseParallelGC not supported in this VM.\n");

    return JNI_ERR;

  } else if (UseG1GC) {

    jio_fprintf(defaultStream::error_stream(), "UseG1GC not supported in this VM.\n");

    return JNI_ERR;

  } else if (UseConcMarkSweepGC) {

    jio_fprintf(defaultStream::error_stream(), "UseConcMarkSweepGC not supported in this VM.\n");

    return JNI_ERR;

#else

  if (UseParallelGC || UseParallelOldGC) {

    _instance = new ParallelArguments();

  } else if (UseG1GC) {

    _instance = new G1Arguments();

  } else if (UseConcMarkSweepGC) {

    _instance = new CMSArguments();

#endif

  } else if (UseSerialGC) {

    _instance = new SerialArguments();

  } else {

    ShouldNotReachHere();

  }

  return JNI_OK;

}