1 /*
2 * Copyright (c) 2005, 2020, 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.
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23 */
24
25 #ifndef SHARE_GC_PARALLEL_PSCOMPACTIONMANAGER_HPP
26 #define SHARE_GC_PARALLEL_PSCOMPACTIONMANAGER_HPP
27
28 #include "gc/parallel/psParallelCompact.hpp"
29 #include "gc/shared/taskqueue.hpp"
30 #include "memory/allocation.hpp"
31 #include "utilities/stack.hpp"
32
33 class MutableSpace;
34 class PSOldGen;
35 class ParCompactionManager;
36 class ObjectStartArray;
37 class ParallelCompactData;
38 class ParMarkBitMap;
39
40 class ParCompactionManager : public CHeapObj<mtGC> {
41 friend class ParMarkBitMap;
42 friend class PSParallelCompact;
43 friend class CompactionWithStealingTask;
44 friend class UpdateAndFillClosure;
45 friend class RefProcTaskExecutor;
46 friend class PCRefProcTask;
47 friend class MarkFromRootsTask;
48 friend class UpdateDensePrefixAndCompactionTask;
49
50 public:
51
52 // ------------------------ Don't putback if not needed
53 // Actions that the compaction manager should take.
54 enum Action {
55 Update,
56 Copy,
57 UpdateAndCopy,
58 CopyAndUpdate,
59 NotValid
60 };
61 // ------------------------ End don't putback if not needed
62
63 private:
64 // 32-bit: 4K * 8 = 32KiB; 64-bit: 8K * 16 = 128KiB
65 #define QUEUE_SIZE (1 << NOT_LP64(12) LP64_ONLY(13))
66 typedef OverflowTaskQueue<ObjArrayTask, mtGC, QUEUE_SIZE> ObjArrayTaskQueue;
67 typedef GenericTaskQueueSet<ObjArrayTaskQueue, mtGC> ObjArrayTaskQueueSet;
68 #undef QUEUE_SIZE
69
70 static ParCompactionManager** _manager_array;
71 static OopTaskQueueSet* _stack_array;
72 static ObjArrayTaskQueueSet* _objarray_queues;
73 static ObjectStartArray* _start_array;
74 static RegionTaskQueueSet* _region_array;
75 static PSOldGen* _old_gen;
76
77 private:
78 OverflowTaskQueue<oop, mtGC> _marking_stack;
79 ObjArrayTaskQueue _objarray_stack;
80 size_t _next_shadow_region;
81
82 // Is there a way to reuse the _marking_stack for the
83 // saving empty regions? For now just create a different
84 // type of TaskQueue.
85 RegionTaskQueue _region_stack;
86
87 static ParMarkBitMap* _mark_bitmap;
88
89 // Contains currently free shadow regions. We use it in
90 // a LIFO fashion for better data locality and utilization.
91 static GrowableArray<size_t>* _shadow_region_array;
92
93 // Provides mutual exclusive access of _shadow_region_array.
94 // See pop/push_shadow_region_mt_safe() below
95 static Monitor* _shadow_region_monitor;
96
97 Action _action;
98
99 HeapWord* _last_query_beg;
100 oop _last_query_obj;
101 size_t _last_query_ret;
102
103 static PSOldGen* old_gen() { return _old_gen; }
104 static ObjectStartArray* start_array() { return _start_array; }
105 static OopTaskQueueSet* stack_array() { return _stack_array; }
106
107 static void initialize(ParMarkBitMap* mbm);
108
109 protected:
110 // Array of task queues. Needed by the task terminator.
111 static RegionTaskQueueSet* region_array() { return _region_array; }
112 OverflowTaskQueue<oop, mtGC>* marking_stack() { return &_marking_stack; }
113
114 // Pushes onto the marking stack. If the marking stack is full,
115 // pushes onto the overflow stack.
116 void stack_push(oop obj);
117 // Do not implement an equivalent stack_pop. Deal with the
118 // marking stack and overflow stack directly.
119
120 public:
121 static const size_t InvalidShadow = ~0;
122 static size_t pop_shadow_region_mt_safe(PSParallelCompact::RegionData* region_ptr);
123 static void push_shadow_region_mt_safe(size_t shadow_region);
124 static void push_shadow_region(size_t shadow_region);
125 static void remove_all_shadow_regions();
126
127 inline size_t next_shadow_region() { return _next_shadow_region; }
128 inline void set_next_shadow_region(size_t record) { _next_shadow_region = record; }
129 inline size_t move_next_shadow_region_by(size_t workers) {
130 _next_shadow_region += workers;
131 return next_shadow_region();
132 }
133
134 void reset_bitmap_query_cache() {
135 _last_query_beg = NULL;
136 _last_query_obj = NULL;
137 _last_query_ret = 0;
138 }
139
140 Action action() { return _action; }
141 void set_action(Action v) { _action = v; }
142
143 // Bitmap query support, cache last query and result
144 HeapWord* last_query_begin() { return _last_query_beg; }
145 oop last_query_object() { return _last_query_obj; }
146 size_t last_query_return() { return _last_query_ret; }
147
148 void set_last_query_begin(HeapWord *new_beg) { _last_query_beg = new_beg; }
149 void set_last_query_object(oop new_obj) { _last_query_obj = new_obj; }
150 void set_last_query_return(size_t new_ret) { _last_query_ret = new_ret; }
151
152 static void reset_all_bitmap_query_caches();
153
154 RegionTaskQueue* region_stack() { return &_region_stack; }
155
156 inline static ParCompactionManager* manager_array(uint index);
157
158 ParCompactionManager();
159
160 // Pushes onto the region stack at the given index. If the
161 // region stack is full,
162 // pushes onto the region overflow stack.
163 static void verify_region_list_empty(uint stack_index);
164 ParMarkBitMap* mark_bitmap() { return _mark_bitmap; }
165
166 // void drain_stacks();
167
168 bool should_update();
169 bool should_copy();
170
171 // Save for later processing. Must not fail.
172 inline void push(oop obj);
173 inline void push_objarray(oop objarray, size_t index);
174 inline void push_region(size_t index);
175
176 // Check mark and maybe push on marking stack.
177 template <typename T> inline void mark_and_push(T* p);
178
179 inline void follow_klass(Klass* klass);
180
181 void follow_class_loader(ClassLoaderData* klass);
182
183 // Access function for compaction managers
184 static ParCompactionManager* gc_thread_compaction_manager(uint index);
185
186 static bool steal(int queue_num, oop& t);
187 static bool steal_objarray(int queue_num, ObjArrayTask& t);
188 static bool steal(int queue_num, size_t& region);
189
190 // Process tasks remaining on any marking stack
191 void follow_marking_stacks();
192 inline bool marking_stacks_empty() const;
193
194 // Process tasks remaining on any stack
195 void drain_region_stacks();
196
197 void follow_contents(oop obj);
198 void follow_array(objArrayOop array, int index);
199
200 void update_contents(oop obj);
201
202 class FollowStackClosure: public VoidClosure {
203 private:
204 ParCompactionManager* _compaction_manager;
205 public:
206 FollowStackClosure(ParCompactionManager* cm) : _compaction_manager(cm) { }
207 virtual void do_void();
208 };
209 };
210
211 inline ParCompactionManager* ParCompactionManager::manager_array(uint index) {
212 assert(_manager_array != NULL, "access of NULL manager_array");
213 assert(index <= ParallelGCThreads, "out of range manager_array access");
214 return _manager_array[index];
215 }
216
217 bool ParCompactionManager::marking_stacks_empty() const {
218 return _marking_stack.is_empty() && _objarray_stack.is_empty();
219 }
220
221 #endif // SHARE_GC_PARALLEL_PSCOMPACTIONMANAGER_HPP