Thu, 01 Jul 2010 21:40:45 -0700
6957084: simplify TaskQueue overflow handling
Reviewed-by: ysr, jmasa
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
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7 * published by the Free Software Foundation.
8 *
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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
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23 */
25 // Move to some global location
26 #define HAS_BEEN_MOVED 0x1501d01d
27 // End move to some global location
30 class MutableSpace;
31 class PSOldGen;
32 class ParCompactionManager;
33 class ObjectStartArray;
34 class ParallelCompactData;
35 class ParMarkBitMap;
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;
45 public:
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
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
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;
74 private:
75 OverflowTaskQueue<oop> _marking_stack;
76 ObjArrayTaskQueue _objarray_stack;
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;
83 #if 1 // does this happen enough to need a per thread stack?
84 GrowableArray<Klass*>* _revisit_klass_stack;
85 GrowableArray<DataLayout*>* _revisit_mdo_stack;
86 #endif
87 static ParMarkBitMap* _mark_bitmap;
89 Action _action;
91 static PSOldGen* old_gen() { return _old_gen; }
92 static ObjectStartArray* start_array() { return _start_array; }
93 static OopTaskQueueSet* stack_array() { return _stack_array; }
95 static void initialize(ParMarkBitMap* mbm);
97 protected:
98 // Array of tasks. Needed by the ParallelTaskTerminator.
99 static RegionTaskQueueSet* region_array() { return _region_array; }
100 OverflowTaskQueue<oop>* marking_stack() { return &_marking_stack; }
101 RegionTaskQueue* region_stack() { return &_region_stack; }
103 // Pushes onto the marking stack. If the marking stack is full,
104 // pushes onto the overflow stack.
105 void stack_push(oop obj);
106 // Do not implement an equivalent stack_pop. Deal with the
107 // marking stack and overflow stack directly.
109 public:
110 Action action() { return _action; }
111 void set_action(Action v) { _action = v; }
113 inline static ParCompactionManager* manager_array(int index);
115 ParCompactionManager();
116 ~ParCompactionManager();
118 void allocate_stacks();
119 void deallocate_stacks();
120 ParMarkBitMap* mark_bitmap() { return _mark_bitmap; }
122 // Take actions in preparation for a compaction.
123 static void reset();
125 // void drain_stacks();
127 bool should_update();
128 bool should_copy();
129 bool should_verify_only();
130 bool should_reset_only();
132 #if 1
133 // Probably stays as a growable array
134 GrowableArray<Klass*>* revisit_klass_stack() { return _revisit_klass_stack; }
135 GrowableArray<DataLayout*>* revisit_mdo_stack() { return _revisit_mdo_stack; }
136 #endif
138 // Save for later processing. Must not fail.
139 inline void push(oop obj) { _marking_stack.push(obj); }
140 inline void push_objarray(oop objarray, size_t index);
141 inline void push_region(size_t index);
143 // Access function for compaction managers
144 static ParCompactionManager* gc_thread_compaction_manager(int index);
146 static bool steal(int queue_num, int* seed, oop& t) {
147 return stack_array()->steal(queue_num, seed, t);
148 }
150 static bool steal_objarray(int queue_num, int* seed, ObjArrayTask& t) {
151 return _objarray_queues->steal(queue_num, seed, t);
152 }
154 static bool steal(int queue_num, int* seed, size_t& region) {
155 return region_array()->steal(queue_num, seed, region);
156 }
158 // Process tasks remaining on any marking stack
159 void follow_marking_stacks();
160 inline bool marking_stacks_empty() const;
162 // Process tasks remaining on any stack
163 void drain_region_stacks();
165 // Debugging support
166 #ifdef ASSERT
167 bool stacks_have_been_allocated();
168 #endif
169 };
171 inline ParCompactionManager* ParCompactionManager::manager_array(int index) {
172 assert(_manager_array != NULL, "access of NULL manager_array");
173 assert(index >= 0 && index <= (int)ParallelGCThreads,
174 "out of range manager_array access");
175 return _manager_array[index];
176 }
178 bool ParCompactionManager::marking_stacks_empty() const {
179 return _marking_stack.is_empty() && _objarray_stack.is_empty();
180 }