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 // Move to some global location
26 #define HAS_BEEN_MOVED 0x1501d01d
27 // End move to some global location
28
29
30 class MutableSpace;
31 class PSOldGen;
32 class ParCompactionManager;
33 class ObjectStartArray;
34 class ParallelCompactData;
35 class ParMarkBitMap;
36
37 class ParCompactionManager : public CHeapObj {
38 friend class ParallelTaskTerminator;
39 friend class ParMarkBitMap;
40 friend class PSParallelCompact;
41 friend class StealRegionCompactionTask;
42 friend class UpdateAndFillClosure;
43 friend class RefProcTaskExecutor;
44
45 public:
46
47 // ------------------------ Don't putback if not needed
48 // Actions that the compaction manager should take.
49 enum Action {
50 Update,
51 Copy,
52 UpdateAndCopy,
53 CopyAndUpdate,
54 VerifyUpdate,
55 ResetObjects,
56 NotValid
57 };
58 // ------------------------ End don't putback if not needed
59
60 private:
61 // 32-bit: 4K * 8 = 32KiB; 64-bit: 8K * 16 = 128KiB
62 #define QUEUE_SIZE (1 << NOT_LP64(12) LP64_ONLY(13))
63 typedef OverflowTaskQueue<ObjArrayTask, QUEUE_SIZE> ObjArrayTaskQueue;
64 typedef GenericTaskQueueSet<ObjArrayTaskQueue> ObjArrayTaskQueueSet;
65 #undef QUEUE_SIZE
66
67 static ParCompactionManager** _manager_array;
68 static OopTaskQueueSet* _stack_array;
69 static ObjArrayTaskQueueSet* _objarray_queues;
70 static ObjectStartArray* _start_array;
71 static RegionTaskQueueSet* _region_array;
72 static PSOldGen* _old_gen;
73
74 private:
75 OverflowTaskQueue<oop> _marking_stack;
76 ObjArrayTaskQueue _objarray_stack;
77
78 // Is there a way to reuse the _marking_stack for the
79 // saving empty regions? For now just create a different
80 // type of TaskQueue.
81 RegionTaskQueue _region_stack;
82
83 Stack<Klass*> _revisit_klass_stack;
84 Stack<DataLayout*> _revisit_mdo_stack;
85
86 static ParMarkBitMap* _mark_bitmap;
87
88 Action _action;
89
90 static PSOldGen* old_gen() { return _old_gen; }
91 static ObjectStartArray* start_array() { return _start_array; }
92 static OopTaskQueueSet* stack_array() { return _stack_array; }
93
94 static void initialize(ParMarkBitMap* mbm);
95
96 protected:
97 // Array of tasks. Needed by the ParallelTaskTerminator.
98 static RegionTaskQueueSet* region_array() { return _region_array; }
99 OverflowTaskQueue<oop>* marking_stack() { return &_marking_stack; }
100 RegionTaskQueue* region_stack() { return &_region_stack; }
101
102 // Pushes onto the marking stack. If the marking stack is full,
103 // pushes onto the overflow stack.
104 void stack_push(oop obj);
105 // Do not implement an equivalent stack_pop. Deal with the
106 // marking stack and overflow stack directly.
107
108 public:
109 Action action() { return _action; }
110 void set_action(Action v) { _action = v; }
111
112 inline static ParCompactionManager* manager_array(int index);
113
114 ParCompactionManager();
115
116 ParMarkBitMap* mark_bitmap() { return _mark_bitmap; }
117
118 // Take actions in preparation for a compaction.
119 static void reset();
120
121 // void drain_stacks();
122
123 bool should_update();
124 bool should_copy();
125 bool should_verify_only();
126 bool should_reset_only();
127
128 Stack<Klass*>* revisit_klass_stack() { return &_revisit_klass_stack; }
129 Stack<DataLayout*>* revisit_mdo_stack() { return &_revisit_mdo_stack; }
130
131 // Save for later processing. Must not fail.
132 inline void push(oop obj) { _marking_stack.push(obj); }
133 inline void push_objarray(oop objarray, size_t index);
134 inline void push_region(size_t index);
135
136 // Access function for compaction managers
137 static ParCompactionManager* gc_thread_compaction_manager(int index);
138
139 static bool steal(int queue_num, int* seed, oop& t) {
140 return stack_array()->steal(queue_num, seed, t);
141 }
142
143 static bool steal_objarray(int queue_num, int* seed, ObjArrayTask& t) {
144 return _objarray_queues->steal(queue_num, seed, t);
145 }
146
147 static bool steal(int queue_num, int* seed, size_t& region) {
148 return region_array()->steal(queue_num, seed, region);
149 }
150
151 // Process tasks remaining on any marking stack
152 void follow_marking_stacks();
153 inline bool marking_stacks_empty() const;
154
155 // Process tasks remaining on any stack
156 void drain_region_stacks();
157
158 };
159
160 inline ParCompactionManager* ParCompactionManager::manager_array(int index) {
161 assert(_manager_array != NULL, "access of NULL manager_array");
162 assert(index >= 0 && index <= (int)ParallelGCThreads,
163 "out of range manager_array access");
164 return _manager_array[index];
165 }
166
167 bool ParCompactionManager::marking_stacks_empty() const {
168 return _marking_stack.is_empty() && _objarray_stack.is_empty();
169 }