/*

 * Copyright (c) 2017, 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 "classfile/classLoaderDataGraph.hpp"

#include "gc/g1/g1CollectedHeap.hpp"

#include "gc/g1/g1ConcurrentMarkBitMap.inline.hpp"

#include "gc/g1/g1FullCollector.hpp"

#include "gc/g1/g1FullGCAdjustTask.hpp"

#include "gc/g1/g1FullGCCompactionPoint.hpp"

#include "gc/g1/g1FullGCMarker.hpp"

#include "gc/g1/g1FullGCOopClosures.inline.hpp"

#include "gc/g1/heapRegion.inline.hpp"

#include "gc/shared/gcTraceTime.inline.hpp"

#include "gc/shared/referenceProcessor.hpp"

#include "gc/shared/weakProcessor.inline.hpp"

#include "logging/log.hpp"

#include "memory/iterator.inline.hpp"

#include "runtime/atomic.hpp"

class G1AdjustLiveClosure : public StackObj {

  G1AdjustClosure* _adjust_closure;

public:

  G1AdjustLiveClosure(G1AdjustClosure* cl) :

    _adjust_closure(cl) { }

  size_t apply(oop object) {

    return object->oop_iterate_size(_adjust_closure);

  }

};

class G1AdjustRegionClosure : public HeapRegionClosure {

  G1CMBitMap* _bitmap;

  uint _worker_id;

 public:

  G1AdjustRegionClosure(G1CMBitMap* bitmap, uint worker_id) :

    _bitmap(bitmap),

    _worker_id(worker_id) { }

  bool do_heap_region(HeapRegion* r) {

    G1AdjustClosure cl;

    if (r->is_humongous()) {

      oop obj = oop(r->humongous_start_region()->bottom());

      obj->oop_iterate(&cl, MemRegion(r->bottom(), r->top()));

    } else if (r->is_open_archive()) {

      // Only adjust the open archive regions, the closed ones

      // never change.

      G1AdjustLiveClosure adjust(&cl);

      r->apply_to_marked_objects(_bitmap, &adjust);

      // Open archive regions will not be compacted and the marking information is

      // no longer needed. Clear it here to avoid having to do it later.

      _bitmap->clear_region(r);

    } else {

      G1AdjustLiveClosure adjust(&cl);

      r->apply_to_marked_objects(_bitmap, &adjust);

    }

    return false;

  }

};

G1FullGCAdjustTask::G1FullGCAdjustTask(G1FullCollector* collector) :

    G1FullGCTask("G1 Adjust", collector),

    _root_processor(G1CollectedHeap::heap(), collector->workers()),

    _references_done(0),

    _weak_proc_task(collector->workers()),

    _hrclaimer(collector->workers()),

    _adjust(),

    _adjust_string_dedup(NULL, &_adjust, G1StringDedup::is_enabled()) {

  // Need cleared claim bits for the roots processing

  ClassLoaderDataGraph::clear_claimed_marks();

}

void G1FullGCAdjustTask::work(uint worker_id) {

  Ticks start = Ticks::now();

  ResourceMark rm;

  // Adjust preserved marks first since they are not balanced.

  G1FullGCMarker* marker = collector()->marker(worker_id);

  marker->preserved_stack()->adjust_during_full_gc();

  // Adjust the weak roots.

  if (Atomic::add(1u, &_references_done) == 1u) { // First incr claims task.

    G1CollectedHeap::heap()->ref_processor_stw()->weak_oops_do(&_adjust);

  }

  AlwaysTrueClosure always_alive;

  _weak_proc_task.work(worker_id, &always_alive, &_adjust);

  CodeBlobToOopClosure adjust_code(&_adjust, CodeBlobToOopClosure::FixRelocations);

  _root_processor.process_all_roots(

      &_adjust,

      &adjust_cld,

      &adjust_code);

  // Adjust string dedup if enabled.

  if (G1StringDedup::is_enabled()) {

    G1StringDedup::parallel_unlink(&_adjust_string_dedup, worker_id);

  }

  // Now adjust pointers region by region

  G1AdjustRegionClosure blk(collector()->mark_bitmap(), worker_id);

  G1CollectedHeap::heap()->heap_region_par_iterate_from_worker_offset(&blk, &_hrclaimer, worker_id);

  log_task("Adjust task", worker_id, start);

}