view src/share/vm/gc_implementation/g1/g1OopClosures.inline.hpp @ 3979:4dfb2df418f2

6484982: G1: process references during evacuation pauses Summary: G1 now uses two reference processors - one is used by concurrent marking and the other is used by STW GCs (both full and incremental evacuation pauses). In an evacuation pause, the reference processor is embedded into the closures used to scan objects. Doing so causes causes reference objects to be 'discovered' by the reference processor. At the end of the evacuation pause, these discovered reference objects are processed - preserving (and copying) referent objects (and their reachable graphs) as appropriate. Reviewed-by: ysr, jwilhelm, brutisso, stefank, tonyp
author johnc
date Thu, 22 Sep 2011 10:57:37 -0700
parents 842b840e67db
children 4406629aa157
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/*
 * 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_G1OOPCLOSURES_INLINE_HPP
#define SHARE_VM_GC_IMPLEMENTATION_G1_G1OOPCLOSURES_INLINE_HPP

#include "gc_implementation/g1/concurrentMark.inline.hpp"
#include "gc_implementation/g1/g1CollectedHeap.hpp"
#include "gc_implementation/g1/g1OopClosures.hpp"
#include "gc_implementation/g1/g1RemSet.hpp"

/*
 * This really ought to be an inline function, but apparently the C++
 * compiler sometimes sees fit to ignore inline declarations.  Sigh.
 */

// This must a ifdef'ed because the counting it controls is in a
// perf-critical inner loop.
#define FILTERINTOCSCLOSURE_DOHISTOGRAMCOUNT 0

template <class T> inline void FilterIntoCSClosure::do_oop_nv(T* p) {
  T heap_oop = oopDesc::load_heap_oop(p);
  if (!oopDesc::is_null(heap_oop) &&
      _g1->obj_in_cs(oopDesc::decode_heap_oop_not_null(heap_oop))) {
    _oc->do_oop(p);
#if FILTERINTOCSCLOSURE_DOHISTOGRAMCOUNT
    if (_dcto_cl != NULL)
      _dcto_cl->incr_count();
#endif
  }
}

#define FILTEROUTOFREGIONCLOSURE_DOHISTOGRAMCOUNT 0

template <class T> inline void FilterOutOfRegionClosure::do_oop_nv(T* p) {
  T heap_oop = oopDesc::load_heap_oop(p);
  if (!oopDesc::is_null(heap_oop)) {
    HeapWord* obj_hw = (HeapWord*)oopDesc::decode_heap_oop_not_null(heap_oop);
    if (obj_hw < _r_bottom || obj_hw >= _r_end) {
      _oc->do_oop(p);
#if FILTEROUTOFREGIONCLOSURE_DOHISTOGRAMCOUNT
      _out_of_region++;
#endif
    }
  }
}

// This closure is applied to the fields of the objects that have just been copied.
template <class T> inline void G1ParScanClosure::do_oop_nv(T* p) {
  T heap_oop = oopDesc::load_heap_oop(p);

  if (!oopDesc::is_null(heap_oop)) {
    oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
    if (_g1->in_cset_fast_test(obj)) {
      // We're not going to even bother checking whether the object is
      // already forwarded or not, as this usually causes an immediate
      // stall. We'll try to prefetch the object (for write, given that
      // we might need to install the forwarding reference) and we'll
      // get back to it when pop it from the queue
      Prefetch::write(obj->mark_addr(), 0);
      Prefetch::read(obj->mark_addr(), (HeapWordSize*2));

      // slightly paranoid test; I'm trying to catch potential
      // problems before we go into push_on_queue to know where the
      // problem is coming from
      assert(obj == oopDesc::load_decode_heap_oop(p),
             "p should still be pointing to obj");
      _par_scan_state->push_on_queue(p);
    } else {
      _par_scan_state->update_rs(_from, p, _par_scan_state->queue_num());
    }
  }
}

template <class T> inline void G1ParPushHeapRSClosure::do_oop_nv(T* p) {
  T heap_oop = oopDesc::load_heap_oop(p);

  if (!oopDesc::is_null(heap_oop)) {
    oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
    if (_g1->in_cset_fast_test(obj)) {
      Prefetch::write(obj->mark_addr(), 0);
      Prefetch::read(obj->mark_addr(), (HeapWordSize*2));

      // Place on the references queue
      _par_scan_state->push_on_queue(p);
    }
  }
}

template <class T> inline void G1CMOopClosure::do_oop_nv(T* p) {
  assert(_g1h->is_in_g1_reserved((HeapWord*) p), "invariant");
  assert(!_g1h->is_on_master_free_list(
                    _g1h->heap_region_containing((HeapWord*) p)), "invariant");

  oop obj = oopDesc::load_decode_heap_oop(p);
  if (_cm->verbose_high()) {
    gclog_or_tty->print_cr("[%d] we're looking at location "
                           "*"PTR_FORMAT" = "PTR_FORMAT,
                           _task->task_id(), p, (void*) obj);
  }
  _task->deal_with_reference(obj);
}

#endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1OOPCLOSURES_INLINE_HPP