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