src/hotspot/share/gc/g1/g1OopClosures.cpp
author tschatzl
Wed, 31 Oct 2018 13:43:57 +0100
changeset 52348 21fdf8d9a8b6
parent 52141 de6dc206a92b
child 58263 4fbc534fdf69
permissions -rw-r--r--
8212911: Unify and micro-optimize handling of non-in-collection set references in oop closures Reviewed-by: kbarrett, sjohanss

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * 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.
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#include "precompiled.hpp"
#include "gc/g1/g1CollectedHeap.inline.hpp"
#include "gc/g1/g1OopClosures.inline.hpp"
#include "gc/g1/g1ParScanThreadState.hpp"
#include "memory/iterator.inline.hpp"
#include "utilities/stack.inline.hpp"

G1ParCopyHelper::G1ParCopyHelper(G1CollectedHeap* g1h,  G1ParScanThreadState* par_scan_state) :
  _g1h(g1h),
  _par_scan_state(par_scan_state),
  _worker_id(par_scan_state->worker_id()),
  _scanned_cld(NULL),
  _cm(_g1h->concurrent_mark())
{ }

G1ScanClosureBase::G1ScanClosureBase(G1CollectedHeap* g1h, G1ParScanThreadState* par_scan_state) :
  _g1h(g1h), _par_scan_state(par_scan_state)
{ }

void G1CLDScanClosure::do_cld(ClassLoaderData* cld) {
  // If the class loader data has not been dirtied we know that there's
  // no references into  the young gen and we can skip it.
  if (!_process_only_dirty || cld->has_modified_oops()) {

    // Tell the closure that this class loader data is the CLD to scavenge
    // and is the one to dirty if oops are left pointing into the young gen.
    _closure->set_scanned_cld(cld);

    // Clean the cld since we're going to scavenge all the metadata.
    // Clear modified oops only if this cld is claimed.
    cld->oops_do(_closure, _claim, /*clear_modified_oops*/true);

    _closure->set_scanned_cld(NULL);

    _closure->trim_queue_partially();
  }
  _count++;
}