view src/share/vm/gc_implementation/g1/g1OopClosures.inline.hpp @ 1886:72a161e62cc4

6991377: G1: race between concurrent refinement and humongous object allocation Summary: There is a race between the concurrent refinement threads and the humongous object allocation that can cause the concurrent refinement threads to corrupt the part of the BOT that it is being initialized by the humongous object allocation operation. The solution is to do the humongous object allocation in careful steps to ensure that the concurrent refinement threads always have a consistent view over the BOT, region contents, and top. The fix includes some very minor tidying up in sparsePRT. Reviewed-by: jcoomes, johnc, ysr
author tonyp
date Sat, 16 Oct 2010 17:12:19 -0400
parents 2d160770d2e5
children f95d63e2154a
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/*
 * Copyright (c) 2001, 2010, 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.
 *
 */

/*
 * 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
    }
  }
}

template <class T> inline void FilterInHeapRegionAndIntoCSClosure::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);
}

template <class T> inline void FilterAndMarkInHeapRegionAndIntoCSClosure::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);
    HeapRegion* hr = _g1->heap_region_containing((HeapWord*) obj);
    if (hr != NULL) {
      if (hr->in_collection_set())
        _oc->do_oop(p);
      else if (!hr->is_young())
        _cm->grayRoot(obj);
    }
  }
}

// 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);
    }
  }
}