1 /*
   2  * Copyright (c) 2002, 2019, 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/classLoaderDataGraph.hpp"
  28 #include "classfile/systemDictionary.hpp"
  29 #include "code/codeCache.hpp"
  30 #include "gc/parallel/gcTaskManager.hpp"
  31 #include "gc/parallel/parallelScavengeHeap.inline.hpp"
  32 #include "gc/parallel/psCardTable.hpp"
  33 #include "gc/parallel/psClosure.inline.hpp"
  34 #include "gc/parallel/psPromotionManager.hpp"
  35 #include "gc/parallel/psPromotionManager.inline.hpp"
  36 #include "gc/parallel/psScavenge.inline.hpp"
  37 #include "gc/parallel/psTasks.hpp"
  38 #include "gc/shared/scavengableNMethods.hpp"
  39 #include "gc/shared/taskqueue.inline.hpp"
  40 #include "memory/iterator.hpp"
  41 #include "memory/resourceArea.hpp"
  42 #include "memory/universe.hpp"
  43 #include "oops/oop.inline.hpp"
  44 #include "runtime/thread.hpp"
  45 #include "runtime/vmThread.hpp"
  46 #include "services/management.hpp"
  47 #if INCLUDE_JVMCI
  48 #include "jvmci/jvmci.hpp"
  49 #endif
  50 
  51 //
  52 // ScavengeRootsTask
  53 //
  54 
  55 void ScavengeRootsTask::do_it(GCTaskManager* manager, uint which) {
  56   assert(ParallelScavengeHeap::heap()->is_gc_active(), "called outside gc");
  57 
  58   PSPromotionManager* pm = PSPromotionManager::gc_thread_promotion_manager(which);
  59   PSScavengeRootsClosure roots_closure(pm);
  60   PSPromoteRootsClosure  roots_to_old_closure(pm);
  61 
  62   switch (_root_type) {
  63     case universe:
  64       Universe::oops_do(&roots_closure);
  65       break;
  66 
  67     case jni_handles:
  68       JNIHandles::oops_do(&roots_closure);
  69       break;
  70 
  71     case threads:
  72     {
  73       ResourceMark rm;
  74       Threads::oops_do(&roots_closure, NULL);
  75     }
  76     break;
  77 
  78     case object_synchronizer:
  79       ObjectSynchronizer::oops_do(&roots_closure);
  80       break;
  81 
  82     case system_dictionary:
  83       SystemDictionary::oops_do(&roots_closure);
  84       break;
  85 
  86     case class_loader_data:
  87     {
  88       PSScavengeCLDClosure cld_closure(pm);
  89       ClassLoaderDataGraph::cld_do(&cld_closure);
  90     }
  91     break;
  92 
  93     case management:
  94       Management::oops_do(&roots_closure);
  95       break;
  96 
  97     case jvmti:
  98       JvmtiExport::oops_do(&roots_closure);
  99       break;
 100 
 101     case code_cache:
 102       {
 103         MarkingCodeBlobClosure code_closure(&roots_to_old_closure, CodeBlobToOopClosure::FixRelocations);
 104         ScavengableNMethods::nmethods_do(&code_closure);
 105         AOTLoader::oops_do(&roots_closure);
 106       }
 107       break;
 108 
 109 #if INCLUDE_JVMCI
 110     case jvmci:
 111       JVMCI::oops_do(&roots_closure);
 112       break;
 113 #endif
 114 
 115     default:
 116       fatal("Unknown root type");
 117   }
 118 
 119   // Do the real work
 120   pm->drain_stacks(false);
 121 }
 122 
 123 //
 124 // ThreadRootsTask
 125 //
 126 
 127 void ThreadRootsTask::do_it(GCTaskManager* manager, uint which) {
 128   assert(ParallelScavengeHeap::heap()->is_gc_active(), "called outside gc");
 129 
 130   PSPromotionManager* pm = PSPromotionManager::gc_thread_promotion_manager(which);
 131   PSScavengeRootsClosure roots_closure(pm);
 132   MarkingCodeBlobClosure roots_in_blobs(&roots_closure, CodeBlobToOopClosure::FixRelocations);
 133 
 134   _thread->oops_do(&roots_closure, &roots_in_blobs);
 135 
 136   // Do the real work
 137   pm->drain_stacks(false);
 138 }
 139 
 140 //
 141 // StealTask
 142 //
 143 
 144 StealTask::StealTask(ParallelTaskTerminator* t) :
 145   _terminator(t) {}
 146 
 147 void StealTask::do_it(GCTaskManager* manager, uint which) {
 148   assert(ParallelScavengeHeap::heap()->is_gc_active(), "called outside gc");
 149 
 150   PSPromotionManager* pm =
 151     PSPromotionManager::gc_thread_promotion_manager(which);
 152   pm->drain_stacks(true);
 153   guarantee(pm->stacks_empty(),
 154             "stacks should be empty at this point");
 155 
 156   while(true) {
 157     StarTask p;
 158     if (PSPromotionManager::steal_depth(which, p)) {
 159       TASKQUEUE_STATS_ONLY(pm->record_steal(p));
 160       pm->process_popped_location_depth(p);
 161       pm->drain_stacks_depth(true);
 162     } else {
 163       if (terminator()->offer_termination()) {
 164         break;
 165       }
 166     }
 167   }
 168   guarantee(pm->stacks_empty(), "stacks should be empty at this point");
 169 }
 170 
 171 //
 172 // OldToYoungRootsTask
 173 //
 174 
 175 void OldToYoungRootsTask::do_it(GCTaskManager* manager, uint which) {
 176   // There are not old-to-young pointers if the old gen is empty.
 177   assert(!_old_gen->object_space()->is_empty(),
 178     "Should not be called is there is no work");
 179   assert(_old_gen != NULL, "Sanity");
 180   assert(_old_gen->object_space()->contains(_gen_top) || _gen_top == _old_gen->object_space()->top(), "Sanity");
 181   assert(_stripe_number < ParallelGCThreads, "Sanity");
 182 
 183   {
 184     PSPromotionManager* pm = PSPromotionManager::gc_thread_promotion_manager(which);
 185     PSCardTable* card_table = ParallelScavengeHeap::heap()->card_table();
 186 
 187     card_table->scavenge_contents_parallel(_old_gen->start_array(),
 188                                            _old_gen->object_space(),
 189                                            _gen_top,
 190                                            pm,
 191                                            _stripe_number,
 192                                            _stripe_total);
 193 
 194     // Do the real work
 195     pm->drain_stacks(false);
 196   }
 197 }