1 /*
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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
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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/stringdedup/stringDedup.hpp"
 33 #include "gc/shared/taskqueue.hpp"
 34 #include "memory/padded.hpp"
 35 #include "utilities/globalDefinitions.hpp"
 36 
 37 //
 38 // psPromotionManager is used by a single thread to manage object survival
 39 // during a scavenge. The promotion manager contains thread local data only.
 40 //
 41 // NOTE! Be careful when allocating the stacks on cheap. If you are going
 42 // to use a promotion manager in more than one thread, the stacks MUST be
 43 // on cheap. This can lead to memory leaks, though, as they are not auto
 44 // deallocated.
 45 //
 46 // FIX ME FIX ME Add a destructor, and don't rely on the user to drain/flush/deallocate!
 47 //
 48 
 49 class MutableSpace;
 50 class PSOldGen;
 51 class ParCompactionManager;
 52 
 53 class PSPromotionManager {
 54   friend class PSScavenge;
 55   friend class ScavengeRootsTask;
 56 
 57  private:
 58   typedef OverflowTaskQueue<ScannerTask, mtGC>           PSScannerTasksQueue;
 59   typedef GenericTaskQueueSet<PSScannerTasksQueue, mtGC> PSScannerTasksQueueSet;
 60 
 61   static PaddedEnd<PSPromotionManager>* _manager_array;
 62   static PSScannerTasksQueueSet*        _stack_array_depth;
 63   static PreservedMarksSet*             _preserved_marks_set;
 64   static PSOldGen*                      _old_gen;
 65   static MutableSpace*                  _young_space;
 66 
 67 #if TASKQUEUE_STATS
 68   size_t                              _array_chunk_pushes;
 69   size_t                              _array_chunk_steals;
 70   size_t                              _arrays_chunked;
 71   size_t                              _array_chunks_processed;
 72 
 73   void print_local_stats(outputStream* const out, uint i) const;
 74   static void print_taskqueue_stats();
 75 
 76   void reset_stats();
 77 #endif // TASKQUEUE_STATS
 78 
 79   PSYoungPromotionLAB                 _young_lab;
 80   PSOldPromotionLAB                   _old_lab;
 81   bool                                _young_gen_is_full;
 82   bool                                _old_gen_is_full;
 83 
 84   PSScannerTasksQueue                 _claimed_stack_depth;
 85 
 86   uint                                _target_stack_size;
 87 
 88   uint                                _array_chunk_size;
 89   uint                                _min_array_size_for_chunking;
 90 
 91   PreservedMarks*                     _preserved_marks;
 92   PromotionFailedInfo                 _promotion_failed_info;
 93 
 94   StringDedup::Requests _string_dedup_requests;
 95 
 96   // Accessors
 97   static PSOldGen* old_gen()         { return _old_gen; }
 98   static MutableSpace* young_space() { return _young_space; }
 99 
100   inline static PSPromotionManager* manager_array(uint index);
101 
102   template <class T> void  process_array_chunk_work(oop obj,
103                                                     int start, int end);
104   void process_array_chunk(PartialArrayScanTask task);
105 
106   void push_depth(ScannerTask task);
107 
108   inline void promotion_trace_event(oop new_obj, oop old_obj, 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   // Promotion methods
137   template<bool promote_immediately> oop copy_to_survivor_space(oop o);
138   oop oop_promotion_failed(oop obj, markWord obj_mark);
139 
140   void reset();
141   void register_preserved_marks(PreservedMarks* preserved_marks);
142   static void restore_preserved_marks();
143 
144   void flush_labs();
145   void flush_string_dedup_requests() { _string_dedup_requests.flush(); }
146 
147   void drain_stacks(bool totally_drain) {
148     drain_stacks_depth(totally_drain);
149   }
150  public:
151   void drain_stacks_cond_depth() {
152     if (claimed_stack_depth()->size() > _target_stack_size) {
153       drain_stacks_depth(false);
154     }
155   }
156   void drain_stacks_depth(bool totally_drain);
157 
158   bool stacks_empty() {
159     return claimed_stack_depth()->is_empty();
160   }
161 
162   inline void process_popped_location_depth(ScannerTask task);
163 
164   static bool should_scavenge(oop* p, bool check_to_space = false);
165   static bool should_scavenge(narrowOop* p, bool check_to_space = false);
166 
167   template <bool promote_immediately, class T>
168   void copy_and_push_safe_barrier(T* p);
169 
170   template <class T> inline void claim_or_forward_depth(T* p);
171 
172   TASKQUEUE_STATS_ONLY(inline void record_steal(ScannerTask task);)
173 
174   void push_contents(oop obj);
175   void push_contents_bounded(oop obj, HeapWord* left, HeapWord* right);
176 };
177 
178 #endif // SHARE_GC_PARALLEL_PSPROMOTIONMANAGER_HPP