1 /*
   2  * Copyright (c) 2014, 2018, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "gc/g1/g1CollectedHeap.inline.hpp"
  27 #include "gc/g1/g1OopClosures.inline.hpp"
  28 #include "gc/g1/g1ParScanThreadState.hpp"
  29 #include "memory/iterator.inline.hpp"
  30 #include "utilities/stack.inline.hpp"
  31 
  32 G1ParCopyHelper::G1ParCopyHelper(G1CollectedHeap* g1h,  G1ParScanThreadState* par_scan_state) :
  33   _g1h(g1h),
  34   _par_scan_state(par_scan_state),
  35   _worker_id(par_scan_state->worker_id()),
  36   _scanned_cld(NULL),
  37   _cm(_g1h->concurrent_mark())
  38 { }
  39 
  40 G1ScanClosureBase::G1ScanClosureBase(G1CollectedHeap* g1h, G1ParScanThreadState* par_scan_state) :
  41   _g1h(g1h), _par_scan_state(par_scan_state), _from_is_young(true)
  42 { }
  43 
  44 void G1CLDScanClosure::do_cld(ClassLoaderData* cld) {
  45   // If the class loader data has not been dirtied we know that there's
  46   // no references into  the young gen and we can skip it.
  47   if (!_process_only_dirty || cld->has_modified_oops()) {
  48 
  49     // Tell the closure that this class loader data is the CLD to scavenge
  50     // and is the one to dirty if oops are left pointing into the young gen.
  51     _closure->set_scanned_cld(cld);
  52 
  53     // Clean the cld since we're going to scavenge all the metadata.
  54     // Clear modified oops only if this cld is claimed.
  55     cld->oops_do(_closure, _claim, /*clear_modified_oops*/true);
  56 
  57     _closure->set_scanned_cld(NULL);
  58 
  59     _closure->trim_queue_partially();
  60   }
  61   _count++;
  62 }