1 /*
   2  * Copyright (c) 2002, 2017, 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 "aot/aotLoader.hpp"
  27 #include "classfile/systemDictionary.hpp"
  28 #include "code/codeCache.hpp"
  29 #include "gc/parallel/cardTableExtension.hpp"
  30 #include "gc/parallel/gcTaskManager.hpp"
  31 #include "gc/parallel/psMarkSweep.hpp"
  32 #include "gc/parallel/psPromotionManager.hpp"
  33 #include "gc/parallel/psPromotionManager.inline.hpp"
  34 #include "gc/parallel/psScavenge.inline.hpp"
  35 #include "gc/parallel/psTasks.hpp"
  36 #include "gc/shared/taskqueue.inline.hpp"
  37 #include "memory/iterator.hpp"
  38 #include "memory/resourceArea.hpp"
  39 #include "memory/universe.hpp"
  40 #include "oops/oop.inline.hpp"
  41 #include "runtime/thread.hpp"
  42 #include "runtime/vmThread.hpp"
  43 #include "services/management.hpp"
  44 
  45 //
  46 // ScavengeRootsTask
  47 //
  48 
  49 void ScavengeRootsTask::do_it(GCTaskManager* manager, uint which) {
  50   assert(ParallelScavengeHeap::heap()->is_gc_active(), "called outside gc");
  51 
  52   PSPromotionManager* pm = PSPromotionManager::gc_thread_promotion_manager(which);
  53   PSScavengeRootsClosure roots_closure(pm);
  54   PSPromoteRootsClosure  roots_to_old_closure(pm);
  55 
  56   switch (_root_type) {
  57     case universe:
  58       Universe::oops_do(&roots_closure);
  59       break;
  60 
  61     case jni_handles:
  62       JNIHandles::oops_do(&roots_closure);
  63       break;
  64 
  65     case threads:
  66     {
  67       ResourceMark rm;
  68       Threads::oops_do(&roots_closure, NULL);
  69     }
  70     break;
  71 
  72     case object_synchronizer:
  73       ObjectSynchronizer::oops_do(&roots_closure);
  74       break;
  75 
  76     case system_dictionary:
  77       SystemDictionary::oops_do(&roots_closure);
  78       break;
  79 
  80     case class_loader_data:
  81       ClassLoaderDataGraph::oops_do(&roots_closure, false);
  82     break;
  83 
  84     case management:
  85       Management::oops_do(&roots_closure);
  86       break;
  87 
  88     case jvmti:
  89       JvmtiExport::oops_do(&roots_closure);
  90       break;
  91 
  92 
  93     case code_cache:
  94       {
  95         MarkingCodeBlobClosure each_scavengable_code_blob(&roots_to_old_closure, CodeBlobToOopClosure::FixRelocations);
  96         CodeCache::scavenge_root_nmethods_do(&each_scavengable_code_blob);
  97         AOTLoader::oops_do(&roots_closure);
  98       }
  99       break;
 100 
 101     default:
 102       fatal("Unknown root type");
 103   }
 104 
 105   // Do the real work
 106   pm->drain_stacks(false);
 107 }
 108 
 109 //
 110 // ThreadRootsTask
 111 //
 112 
 113 void ThreadRootsTask::do_it(GCTaskManager* manager, uint which) {
 114   assert(ParallelScavengeHeap::heap()->is_gc_active(), "called outside gc");
 115 
 116   PSPromotionManager* pm = PSPromotionManager::gc_thread_promotion_manager(which);
 117   PSScavengeRootsClosure roots_closure(pm);
 118   MarkingCodeBlobClosure roots_in_blobs(&roots_closure, CodeBlobToOopClosure::FixRelocations);
 119 
 120   if (_java_thread != NULL)
 121     _java_thread->oops_do(&roots_closure, &roots_in_blobs);
 122 
 123   if (_vm_thread != NULL)
 124     _vm_thread->oops_do(&roots_closure, &roots_in_blobs);
 125 
 126   // Do the real work
 127   pm->drain_stacks(false);
 128 }
 129 
 130 //
 131 // StealTask
 132 //
 133 
 134 StealTask::StealTask(ParallelTaskTerminator* t) :
 135   _terminator(t) {}
 136 
 137 void StealTask::do_it(GCTaskManager* manager, uint which) {
 138   assert(ParallelScavengeHeap::heap()->is_gc_active(), "called outside gc");
 139 
 140   PSPromotionManager* pm =
 141     PSPromotionManager::gc_thread_promotion_manager(which);
 142   pm->drain_stacks(true);
 143   guarantee(pm->stacks_empty(),
 144             "stacks should be empty at this point");
 145 
 146   int random_seed = 17;
 147   while(true) {
 148     StarTask p;
 149     if (PSPromotionManager::steal_depth(which, &random_seed, p)) {
 150       TASKQUEUE_STATS_ONLY(pm->record_steal(p));
 151       pm->process_popped_location_depth(p);
 152       pm->drain_stacks_depth(true);
 153     } else {
 154       if (terminator()->offer_termination()) {
 155         break;
 156       }
 157     }
 158   }
 159   guarantee(pm->stacks_empty(), "stacks should be empty at this point");
 160 }
 161 
 162 //
 163 // OldToYoungRootsTask
 164 //
 165 
 166 void OldToYoungRootsTask::do_it(GCTaskManager* manager, uint which) {
 167   // There are not old-to-young pointers if the old gen is empty.
 168   assert(!_old_gen->object_space()->is_empty(),
 169     "Should not be called is there is no work");
 170   assert(_old_gen != NULL, "Sanity");
 171   assert(_old_gen->object_space()->contains(_gen_top) || _gen_top == _old_gen->object_space()->top(), "Sanity");
 172   assert(_stripe_number < ParallelGCThreads, "Sanity");
 173 
 174   {
 175     PSPromotionManager* pm = PSPromotionManager::gc_thread_promotion_manager(which);
 176     CardTableExtension* card_table =
 177       barrier_set_cast<CardTableExtension>(ParallelScavengeHeap::heap()->barrier_set());
 178 
 179     card_table->scavenge_contents_parallel(_old_gen->start_array(),
 180                                            _old_gen->object_space(),
 181                                            _gen_top,
 182                                            pm,
 183                                            _stripe_number,
 184                                            _stripe_total);
 185 
 186     // Do the real work
 187     pm->drain_stacks(false);
 188   }
 189 }