1 /*
  2  * Copyright (c) 2005, 2019, 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/shared/taskqueue.hpp"
 29 #include "memory/allocation.hpp"
 30 #include "utilities/stack.hpp"
 31 
 32 class MutableSpace;
 33 class PSOldGen;
 34 class ParCompactionManager;
 35 class ObjectStartArray;
 36 class ParallelCompactData;
 37 class ParMarkBitMap;
 38 
 39 class ParCompactionManager : public CHeapObj<mtGC> {
 40   friend class ParallelTaskTerminator;
 41   friend class ParMarkBitMap;
 42   friend class PSParallelCompact;
 43   friend class CompactionWithStealingTask;
 44   friend class UpdateAndFillClosure;
 45   friend class RefProcTaskExecutor;
 46   friend class IdleGCTask;
 47 
 48  public:
 49 
 50 // ------------------------  Don't putback if not needed
 51   // Actions that the compaction manager should take.
 52   enum Action {
 53     Update,
 54     Copy,
 55     UpdateAndCopy,
 56     CopyAndUpdate,
 57     NotValid
 58   };
 59 // ------------------------  End don't putback if not needed
 60 
 61  private:
 62   // 32-bit:  4K * 8 = 32KiB; 64-bit:  8K * 16 = 128KiB
 63   #define QUEUE_SIZE (1 << NOT_LP64(12) LP64_ONLY(13))
 64   typedef OverflowTaskQueue<ObjArrayTask, mtGC, QUEUE_SIZE> ObjArrayTaskQueue;
 65   typedef GenericTaskQueueSet<ObjArrayTaskQueue, mtGC>      ObjArrayTaskQueueSet;
 66   #undef QUEUE_SIZE
 67 
 68   static ParCompactionManager** _manager_array;
 69   static OopTaskQueueSet*       _stack_array;
 70   static ObjArrayTaskQueueSet*  _objarray_queues;
 71   static ObjectStartArray*      _start_array;
 72   static RegionTaskQueueSet*    _region_array;
 73   static PSOldGen*              _old_gen;
 74 
 75 private:
 76   OverflowTaskQueue<oop, mtGC>        _marking_stack;
 77   ObjArrayTaskQueue             _objarray_stack;
 78 
 79   // Is there a way to reuse the _marking_stack for the
 80   // saving empty regions?  For now just create a different
 81   // type of TaskQueue.
 82   RegionTaskQueue              _region_stack;
 83 
 84   static ParMarkBitMap* _mark_bitmap;
 85 
 86   Action _action;
 87 
 88   HeapWord* _last_query_beg;
 89   oop _last_query_obj;
 90   size_t _last_query_ret;
 91 
 92   static PSOldGen* old_gen()             { return _old_gen; }
 93   static ObjectStartArray* start_array() { return _start_array; }
 94   static OopTaskQueueSet* stack_array()  { return _stack_array; }
 95 
 96   static void initialize(ParMarkBitMap* mbm);
 97 
 98  protected:
 99   // Array of tasks.  Needed by the ParallelTaskTerminator.
100   static RegionTaskQueueSet* region_array()      { return _region_array; }
101   OverflowTaskQueue<oop, mtGC>*  marking_stack()       { return &_marking_stack; }
102 
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.
108 
109  public:
110   void reset_bitmap_query_cache() {
111     _last_query_beg = NULL;
112     _last_query_obj = NULL;
113     _last_query_ret = 0;
114   }
115 
116   Action action() { return _action; }
117   void set_action(Action v) { _action = v; }
118 
119   // Bitmap query support, cache last query and result
120   HeapWord* last_query_begin() { return _last_query_beg; }
121   oop last_query_object() { return _last_query_obj; }
122   size_t last_query_return() { return _last_query_ret; }
123 
124   void set_last_query_begin(HeapWord *new_beg) { _last_query_beg = new_beg; }
125   void set_last_query_object(oop new_obj) { _last_query_obj = new_obj; }
126   void set_last_query_return(size_t new_ret) { _last_query_ret = new_ret; }
127 
128   static void reset_all_bitmap_query_caches();
129 
130   RegionTaskQueue* region_stack()                { return &_region_stack; }
131 
132   inline static ParCompactionManager* manager_array(uint index);
133 
134   ParCompactionManager();
135 
136   // Pushes onto the region stack at the given index.  If the
137   // region stack is full,
138   // pushes onto the region overflow stack.
139   static void verify_region_list_empty(uint stack_index);
140   ParMarkBitMap* mark_bitmap() { return _mark_bitmap; }
141 
142   // void drain_stacks();
143 
144   bool should_update();
145   bool should_copy();
146 
147   // Save for later processing.  Must not fail.
148   inline void push(oop obj);
149   inline void push_objarray(oop objarray, size_t index);
150   inline void push_region(size_t index);
151 
152   // Check mark and maybe push on marking stack.
153   template <typename T> inline void mark_and_push(T* p);
154 
155   inline void follow_klass(Klass* klass);
156 
157   void follow_class_loader(ClassLoaderData* klass);
158 
159   // Access function for compaction managers
160   static ParCompactionManager* gc_thread_compaction_manager(uint index);
161 
162   static bool steal(int queue_num, oop& t);
163   static bool steal_objarray(int queue_num, ObjArrayTask& t);
164   static bool steal(int queue_num, size_t& region);
165 
166   // Process tasks remaining on any marking stack
167   void follow_marking_stacks();
168   inline bool marking_stacks_empty() const;
169 
170   // Process tasks remaining on any stack
171   void drain_region_stacks();
172 
173   void follow_contents(oop obj);
174   void follow_array(objArrayOop array, int index);
175 
176   void update_contents(oop obj);
177 
178   class FollowStackClosure: public VoidClosure {
179    private:
180     ParCompactionManager* _compaction_manager;
181    public:
182     FollowStackClosure(ParCompactionManager* cm) : _compaction_manager(cm) { }
183     virtual void do_void();
184   };
185 };
186 
187 inline ParCompactionManager* ParCompactionManager::manager_array(uint index) {
188   assert(_manager_array != NULL, "access of NULL manager_array");
189   assert(index <= ParallelGCThreads, "out of range manager_array access");
190   return _manager_array[index];
191 }
192 
193 bool ParCompactionManager::marking_stacks_empty() const {
194   return _marking_stack.is_empty() && _objarray_stack.is_empty();
195 }
196 
197 #endif // SHARE_GC_PARALLEL_PSCOMPACTIONMANAGER_HPP