/*

 * Copyright (c) 2001, 2011, 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.

 *

 */

#ifndef SHARE_VM_GC_IMPLEMENTATION_G1_CONCURRENTMARK_INLINE_HPP

#define SHARE_VM_GC_IMPLEMENTATION_G1_CONCURRENTMARK_INLINE_HPP

#include "gc_implementation/g1/concurrentMark.hpp"

#include "gc_implementation/g1/g1CollectedHeap.inline.hpp"

inline void CMTask::push(oop obj) {

  HeapWord* objAddr = (HeapWord*) obj;

  assert(_g1h->is_in_g1_reserved(objAddr), "invariant");

  assert(!_g1h->is_on_master_free_list(

              _g1h->heap_region_containing((HeapWord*) objAddr)), "invariant");

  assert(!_g1h->is_obj_ill(obj), "invariant");

  assert(_nextMarkBitMap->isMarked(objAddr), "invariant");

  if (_cm->verbose_high()) {

    gclog_or_tty->print_cr("[%d] pushing "PTR_FORMAT, _task_id, (void*) obj);

  }

  if (!_task_queue->push(obj)) {

    // The local task queue looks full. We need to push some entries

    // to the global stack.

    if (_cm->verbose_medium()) {

      gclog_or_tty->print_cr("[%d] task queue overflow, "

                             "moving entries to the global stack",

                             _task_id);

    }

    move_entries_to_global_stack();

    // this should succeed since, even if we overflow the global

    // stack, we should have definitely removed some entries from the

    // local queue. So, there must be space on it.

    bool success = _task_queue->push(obj);

    assert(success, "invariant");

  }

  statsOnly( int tmp_size = _task_queue->size();

               _local_max_size = tmp_size;

             ++_local_pushes );

}

// This determines whether the method below will check both the local

// and global fingers when determining whether to push on the stack a

// gray object (value 1) or whether it will only check the global one

// (value 0). The tradeoffs are that the former will be a bit more

// accurate and possibly push less on the stack, but it might also be

// a little bit slower.

#define _CHECK_BOTH_FINGERS_      1

inline void CMTask::deal_with_reference(oop obj) {

  if (_cm->verbose_high()) {

    gclog_or_tty->print_cr("[%d] we're dealing with reference = "PTR_FORMAT,

                           _task_id, (void*) obj);

  }

  ++_refs_reached;

  HeapWord* objAddr = (HeapWord*) obj;

  assert(obj->is_oop_or_null(true /* ignore mark word */), "Error");

 if (_g1h->is_in_g1_reserved(objAddr)) {

    assert(obj != NULL, "null check is implicit");

    if (!_nextMarkBitMap->isMarked(objAddr)) {

      // Only get the containing region if the object is not marked on the

      // bitmap (otherwise, it's a waste of time since we won't do

      // anything with it).

      HeapRegion* hr = _g1h->heap_region_containing_raw(obj);

      if (!hr->obj_allocated_since_next_marking(obj)) {

        if (_cm->verbose_high()) {

          gclog_or_tty->print_cr("[%d] "PTR_FORMAT" is not considered marked",

                                 _task_id, (void*) obj);

        }

        // we need to mark it first

        if (_nextMarkBitMap->parMark(objAddr)) {

          // No OrderAccess:store_load() is needed. It is implicit in the

          // CAS done in parMark(objAddr) above

          HeapWord* global_finger = _cm->finger();

#if _CHECK_BOTH_FINGERS_

          // we will check both the local and global fingers

          if (_finger != NULL && objAddr < _finger) {

            if (_cm->verbose_high()) {

              gclog_or_tty->print_cr("[%d] below the local finger ("PTR_FORMAT"), "

                                     "pushing it", _task_id, _finger);

            }

            push(obj);

          } else if (_curr_region != NULL && objAddr < _region_limit) {

            // do nothing

          } else if (objAddr < global_finger) {

            // Notice that the global finger might be moving forward

            // concurrently. This is not a problem. In the worst case, we

            // mark the object while it is above the global finger and, by

            // the time we read the global finger, it has moved forward

            // passed this object. In this case, the object will probably

            // be visited when a task is scanning the region and will also

            // be pushed on the stack. So, some duplicate work, but no

            // correctness problems.

            if (_cm->verbose_high()) {

              gclog_or_tty->print_cr("[%d] below the global finger "

                                     "("PTR_FORMAT"), pushing it",

                                     _task_id, global_finger);

            }

            push(obj);

          } else {

            // do nothing

          }

#else // _CHECK_BOTH_FINGERS_

          // we will only check the global finger

          if (objAddr < global_finger) {

            // see long comment above

            if (_cm->verbose_high()) {

              gclog_or_tty->print_cr("[%d] below the global finger "

                                     "("PTR_FORMAT"), pushing it",

                                     _task_id, global_finger);

            }

            push(obj);

          }

#endif // _CHECK_BOTH_FINGERS_

        }

      }

    }

  }

}

#endif // SHARE_VM_GC_IMPLEMENTATION_G1_CONCURRENTMARK_INLINE_HPP