1 /*
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  3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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  6  * under the terms of the GNU General Public License version 2 only, as
  7  * published by the Free Software Foundation.
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  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).
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 24 
 25 #ifndef SHARE_GC_PARALLEL_PSPROMOTIONMANAGER_HPP
 26 #define SHARE_GC_PARALLEL_PSPROMOTIONMANAGER_HPP
 27 
 28 #include "gc/parallel/psPromotionLAB.hpp"
 29 #include "gc/shared/copyFailedInfo.hpp"
 30 #include "gc/shared/gcTrace.hpp"
 31 #include "gc/shared/preservedMarks.hpp"
 32 #include "gc/shared/taskqueue.hpp"
 33 #include "memory/padded.hpp"
 34 #include "utilities/globalDefinitions.hpp"
 35 
 36 //
 37 // psPromotionManager is used by a single thread to manage object survival
 38 // during a scavenge. The promotion manager contains thread local data only.
 39 //
 40 // NOTE! Be careful when allocating the stacks on cheap. If you are going
 41 // to use a promotion manager in more than one thread, the stacks MUST be
 42 // on cheap. This can lead to memory leaks, though, as they are not auto
 43 // deallocated.
 44 //
 45 // FIX ME FIX ME Add a destructor, and don't rely on the user to drain/flush/deallocate!
 46 //
 47 
 48 class MutableSpace;
 49 class PSOldGen;
 50 class ParCompactionManager;
 51 
 52 class PSPromotionManager {
 53   friend class PSScavenge;
 54   friend class ScavengeRootsTask;
 55 
 56  private:
 57   typedef OverflowTaskQueue<ScannerTask, mtGC>           PSScannerTasksQueue;
 58   typedef GenericTaskQueueSet<PSScannerTasksQueue, mtGC> PSScannerTasksQueueSet;
 59 
 60   static PaddedEnd<PSPromotionManager>* _manager_array;
 61   static PSScannerTasksQueueSet*        _stack_array_depth;
 62   static PreservedMarksSet*             _preserved_marks_set;
 63   static PSOldGen*                      _old_gen;
 64   static MutableSpace*                  _young_space;
 65 
 66 #if TASKQUEUE_STATS
 67   size_t                              _array_chunk_pushes;
 68   size_t                              _array_chunk_steals;
 69   size_t                              _arrays_chunked;
 70   size_t                              _array_chunks_processed;
 71 
 72   void print_local_stats(outputStream* const out, uint i) const;
 73   static void print_taskqueue_stats();
 74 
 75   void reset_stats();
 76 #endif // TASKQUEUE_STATS
 77 
 78   PSYoungPromotionLAB                 _young_lab;
 79   PSOldPromotionLAB                   _old_lab;
 80   bool                                _young_gen_is_full;
 81   bool                                _old_gen_is_full;
 82 
 83   PSScannerTasksQueue                 _claimed_stack_depth;
 84   OverflowTaskQueue<oop, mtGC>        _claimed_stack_breadth;
 85 
 86   bool                                _totally_drain;
 87   uint                                _target_stack_size;
 88 
 89   uint                                _array_chunk_size;
 90   uint                                _min_array_size_for_chunking;
 91 
 92   PreservedMarks*                     _preserved_marks;
 93   PromotionFailedInfo                 _promotion_failed_info;
 94 
 95   // Accessors
 96   static PSOldGen* old_gen()         { return _old_gen; }
 97   static MutableSpace* young_space() { return _young_space; }
 98 
 99   inline static PSPromotionManager* manager_array(uint index);
100 
101   template <class T> void  process_array_chunk_work(oop obj,
102                                                     int start, int end);
103   void process_array_chunk(PartialArrayScanTask task);
104 
105   void push_depth(ScannerTask task);
106 
107   inline void promotion_trace_event(oop new_obj, oop old_obj,
108                                     Klass* klass, size_t obj_size,
109                                     uint age, bool tenured,
110                                     const PSPromotionLAB* lab);
111 
112   static PSScannerTasksQueueSet* stack_array_depth() { return _stack_array_depth; }
113 
114   template<bool promote_immediately>
115   oop copy_unmarked_to_survivor_space(oop o, markWord m);
116 
117  public:
118   // Static
119   static void initialize();
120 
121   static void pre_scavenge();
122   static bool post_scavenge(YoungGCTracer& gc_tracer);
123 
124   static PSPromotionManager* gc_thread_promotion_manager(uint index);
125   static PSPromotionManager* vm_thread_promotion_manager();
126 
127   static bool steal_depth(int queue_num, ScannerTask& t);
128 
129   PSPromotionManager();
130 
131   // Accessors
132   PSScannerTasksQueue* claimed_stack_depth() {
133     return &_claimed_stack_depth;
134   }
135 
136   bool young_gen_is_full()             { return _young_gen_is_full; }
137 
138   bool old_gen_is_full()               { return _old_gen_is_full; }
139   void set_old_gen_is_full(bool state) { _old_gen_is_full = state; }
140 
141   // Promotion methods
142   template<bool promote_immediately> oop copy_to_survivor_space(oop o);
143   oop oop_promotion_failed(oop obj, markWord obj_mark);
144 
145   void reset();
146   void register_preserved_marks(PreservedMarks* preserved_marks);
147   static void restore_preserved_marks();
148 
149   void flush_labs();
150   void drain_stacks(bool totally_drain) {
151     drain_stacks_depth(totally_drain);
152   }
153  public:
154   void drain_stacks_cond_depth() {
155     if (claimed_stack_depth()->size() > _target_stack_size) {
156       drain_stacks_depth(false);
157     }
158   }
159   void drain_stacks_depth(bool totally_drain);
160 
161   bool stacks_empty() {
162     return claimed_stack_depth()->is_empty();
163   }
164 
165   inline void process_popped_location_depth(ScannerTask task);
166 
167   static bool should_scavenge(oop* p, bool check_to_space = false);
168   static bool should_scavenge(narrowOop* p, bool check_to_space = false);
169 
170   template <bool promote_immediately, class T>
171   void copy_and_push_safe_barrier(T* p);
172 
173   template <class T> inline void claim_or_forward_depth(T* p);
174 
175   TASKQUEUE_STATS_ONLY(inline void record_steal(ScannerTask task);)
176 
177   void push_contents(oop obj);
178 };
179 
180 #endif // SHARE_GC_PARALLEL_PSPROMOTIONMANAGER_HPP