1 /*
2 * Copyright (c) 2005, 2010, 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 "classfile/systemDictionary.hpp"
27 #include "gc_implementation/parallelScavenge/gcTaskManager.hpp"
28 #include "gc_implementation/parallelScavenge/objectStartArray.hpp"
29 #include "gc_implementation/parallelScavenge/parMarkBitMap.hpp"
30 #include "gc_implementation/parallelScavenge/parallelScavengeHeap.hpp"
31 #include "gc_implementation/parallelScavenge/psCompactionManager.hpp"
32 #include "gc_implementation/parallelScavenge/psOldGen.hpp"
33 #include "gc_implementation/parallelScavenge/psParallelCompact.hpp"
34 #include "oops/objArrayKlass.inline.hpp"
35 #include "oops/oop.hpp"
36 #include "oops/oop.inline.hpp"
37 #include "oops/oop.pcgc.inline.hpp"
38 #include "utilities/stack.inline.hpp"
39
40 PSOldGen* ParCompactionManager::_old_gen = NULL;
41 ParCompactionManager** ParCompactionManager::_manager_array = NULL;
42 OopTaskQueueSet* ParCompactionManager::_stack_array = NULL;
43 ParCompactionManager::ObjArrayTaskQueueSet*
44 ParCompactionManager::_objarray_queues = NULL;
45 ObjectStartArray* ParCompactionManager::_start_array = NULL;
46 ParMarkBitMap* ParCompactionManager::_mark_bitmap = NULL;
47 RegionTaskQueueSet* ParCompactionManager::_region_array = NULL;
48
49 ParCompactionManager::ParCompactionManager() :
50 _action(CopyAndUpdate) {
51
52 ParallelScavengeHeap* heap = (ParallelScavengeHeap*)Universe::heap();
53 assert(heap->kind() == CollectedHeap::ParallelScavengeHeap, "Sanity");
54
55 _old_gen = heap->old_gen();
56 _start_array = old_gen()->start_array();
57
58 marking_stack()->initialize();
59 _objarray_stack.initialize();
60 region_stack()->initialize();
61 }
62
63 void ParCompactionManager::initialize(ParMarkBitMap* mbm) {
64 assert(PSParallelCompact::gc_task_manager() != NULL,
65 "Needed for initialization");
66
67 _mark_bitmap = mbm;
68
69 uint parallel_gc_threads = PSParallelCompact::gc_task_manager()->workers();
70
71 assert(_manager_array == NULL, "Attempt to initialize twice");
72 _manager_array = NEW_C_HEAP_ARRAY(ParCompactionManager*, parallel_gc_threads+1 );
73 guarantee(_manager_array != NULL, "Could not allocate manager_array");
74
75 _stack_array = new OopTaskQueueSet(parallel_gc_threads);
76 guarantee(_stack_array != NULL, "Could not allocate stack_array");
77 _objarray_queues = new ObjArrayTaskQueueSet(parallel_gc_threads);
78 guarantee(_objarray_queues != NULL, "Could not allocate objarray_queues");
79 _region_array = new RegionTaskQueueSet(parallel_gc_threads);
80 guarantee(_region_array != NULL, "Could not allocate region_array");
81
82 // Create and register the ParCompactionManager(s) for the worker threads.
83 for(uint i=0; i<parallel_gc_threads; i++) {
84 _manager_array[i] = new ParCompactionManager();
85 guarantee(_manager_array[i] != NULL, "Could not create ParCompactionManager");
86 stack_array()->register_queue(i, _manager_array[i]->marking_stack());
87 _objarray_queues->register_queue(i, &_manager_array[i]->_objarray_stack);
88 region_array()->register_queue(i, _manager_array[i]->region_stack());
89 }
90
91 // The VMThread gets its own ParCompactionManager, which is not available
92 // for work stealing.
93 _manager_array[parallel_gc_threads] = new ParCompactionManager();
94 guarantee(_manager_array[parallel_gc_threads] != NULL,
95 "Could not create ParCompactionManager");
96 assert(PSParallelCompact::gc_task_manager()->workers() != 0,
97 "Not initialized?");
98 }
99
100 bool ParCompactionManager::should_update() {
101 assert(action() != NotValid, "Action is not set");
102 return (action() == ParCompactionManager::Update) ||
103 (action() == ParCompactionManager::CopyAndUpdate) ||
104 (action() == ParCompactionManager::UpdateAndCopy);
105 }
106
107 bool ParCompactionManager::should_copy() {
108 assert(action() != NotValid, "Action is not set");
109 return (action() == ParCompactionManager::Copy) ||
110 (action() == ParCompactionManager::CopyAndUpdate) ||
111 (action() == ParCompactionManager::UpdateAndCopy);
112 }
113
114 bool ParCompactionManager::should_verify_only() {
115 assert(action() != NotValid, "Action is not set");
116 return action() == ParCompactionManager::VerifyUpdate;
117 }
118
119 bool ParCompactionManager::should_reset_only() {
120 assert(action() != NotValid, "Action is not set");
121 return action() == ParCompactionManager::ResetObjects;
122 }
123
124 ParCompactionManager*
125 ParCompactionManager::gc_thread_compaction_manager(int index) {
126 assert(index >= 0 && index < (int)ParallelGCThreads, "index out of range");
127 assert(_manager_array != NULL, "Sanity");
128 return _manager_array[index];
129 }
130
131 void ParCompactionManager::reset() {
132 for(uint i = 0; i < ParallelGCThreads + 1; i++) {
133 assert(manager_array(i)->revisit_klass_stack()->is_empty(), "sanity");
134 assert(manager_array(i)->revisit_mdo_stack()->is_empty(), "sanity");
135 }
136 }
137
138 void ParCompactionManager::follow_marking_stacks() {
139 do {
140 // Drain the overflow stack first, to allow stealing from the marking stack.
141 oop obj;
142 while (marking_stack()->pop_overflow(obj)) {
143 obj->follow_contents(this);
144 }
145 while (marking_stack()->pop_local(obj)) {
146 obj->follow_contents(this);
147 }
148
149 // Process ObjArrays one at a time to avoid marking stack bloat.
150 ObjArrayTask task;
151 if (_objarray_stack.pop_overflow(task)) {
152 objArrayKlass* const k = (objArrayKlass*)task.obj()->blueprint();
153 k->oop_follow_contents(this, task.obj(), task.index());
154 } else if (_objarray_stack.pop_local(task)) {
155 objArrayKlass* const k = (objArrayKlass*)task.obj()->blueprint();
156 k->oop_follow_contents(this, task.obj(), task.index());
157 }
158 } while (!marking_stacks_empty());
159
160 assert(marking_stacks_empty(), "Sanity");
161 }
162
163 void ParCompactionManager::drain_region_stacks() {
164 do {
165 // Drain overflow stack first so other threads can steal.
166 size_t region_index;
167 while (region_stack()->pop_overflow(region_index)) {
168 PSParallelCompact::fill_and_update_region(this, region_index);
169 }
170
171 while (region_stack()->pop_local(region_index)) {
172 PSParallelCompact::fill_and_update_region(this, region_index);
173 }
174 } while (!region_stack()->is_empty());
175 }