/*

 * Copyright (c) 2015, 2017, 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/z/zHeap.hpp"

#include "gc/z/zOopClosures.inline.hpp"

#include "gc/z/zPage.hpp"

#include "gc/z/zRelocate.hpp"

#include "gc/z/zRelocationSet.inline.hpp"

#include "gc/z/zRootsIterator.hpp"

#include "gc/z/zTask.hpp"

#include "gc/z/zWorkers.hpp"

ZRelocate::ZRelocate(ZWorkers* workers) :

    _workers(workers) {}

class ZRelocateRootsTask : public ZTask {

private:

  ZRootsIterator _roots;

public:

  ZRelocateRootsTask() :

      ZTask("ZRelocateRootsTask"),

      _roots() {}

  virtual void work() {

    // During relocation we need to visit the JVMTI

    // export weak roots to rehash the JVMTI tag map

    ZRelocateRootOopClosure cl;

    _roots.oops_do(&cl, true /* visit_jvmti_weak_export */);

  }

};

void ZRelocate::start() {

  ZRelocateRootsTask task;

  _workers->run_parallel(&task);

}

class ZRelocateObjectClosure : public ObjectClosure {

private:

  ZPage* const _page;

public:

  ZRelocateObjectClosure(ZPage* page) :

      _page(page) {}

  virtual void do_object(oop o) {

    _page->relocate_object(ZOop::to_address(o));

  }

};

bool ZRelocate::work(ZRelocationSetParallelIterator* iter) {

  bool success = true;

  // Relocate pages in the relocation set

  for (ZPage* page; iter->next(&page);) {

    // Relocate objects in page

    ZRelocateObjectClosure cl(page);

    page->object_iterate(&cl);

    if (ZVerifyForwarding) {

      page->verify_forwarding();

    }

    if (page->is_pinned()) {

      // Relocation failed, page is now pinned

      success = false;

    } else {

      // Relocation succeeded, release page

      ZHeap::heap()->release_page(page, true /* reclaimed */);

    }

  }

  return success;

}

class ZRelocateTask : public ZTask {

private:

  ZRelocate* const               _relocate;

  ZRelocationSetParallelIterator _iter;

  bool                           _failed;

public:

  ZRelocateTask(ZRelocate* relocate, ZRelocationSet* relocation_set) :

      ZTask("ZRelocateTask"),

      _relocate(relocate),

      _iter(relocation_set),

      _failed(false) {}

  virtual void work() {

    if (!_relocate->work(&_iter)) {

      _failed = true;

    }

  }

  bool failed() const {

    return _failed;

  }

};

bool ZRelocate::relocate(ZRelocationSet* relocation_set) {

  ZRelocateTask task(this, relocation_set);

  _workers->run_concurrent(&task);

  return !task.failed();

}