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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 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/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   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   StringDedup::Requests _string_dedup_requests;
 96 
 97   // Accessors
 98   static PSOldGen* old_gen()         { return _old_gen; }
 99   static MutableSpace* young_space() { return _young_space; }
100 
101   inline static PSPromotionManager* manager_array(uint index);
102 
103   template <class T> void  process_array_chunk_work(oop obj,
104                                                     int start, int end);
105   void process_array_chunk(PartialArrayScanTask task);
106 
107   void push_depth(ScannerTask task);
108 
109   inline void promotion_trace_event(oop new_obj, oop old_obj, size_t obj_size,
110                                     uint age, bool tenured,
111                                     const PSPromotionLAB* lab);
112 
113   static PSScannerTasksQueueSet* stack_array_depth() { return _stack_array_depth; }
114 
115   template<bool promote_immediately>
116   oop copy_unmarked_to_survivor_space(oop o, markWord m);
117 
118  public:
119   // Static
120   static void initialize();
121 
122   static void pre_scavenge();
123   static bool post_scavenge(YoungGCTracer& gc_tracer);
124 
125   static PSPromotionManager* gc_thread_promotion_manager(uint index);
126   static PSPromotionManager* vm_thread_promotion_manager();
127 
128   static bool steal_depth(int queue_num, ScannerTask& t);
129 
130   PSPromotionManager();
131 
132   // Accessors
133   PSScannerTasksQueue* claimed_stack_depth() {
134     return &_claimed_stack_depth;
135   }
136 
137   bool young_gen_is_full()             { return _young_gen_is_full; }
138 
139   bool old_gen_is_full()               { return _old_gen_is_full; }
140   void set_old_gen_is_full(bool state) { _old_gen_is_full = state; }
141 
142   // Promotion methods
143   template<bool promote_immediately> oop copy_to_survivor_space(oop o);
144   oop oop_promotion_failed(oop obj, markWord obj_mark);
145 
146   void reset();
147   void register_preserved_marks(PreservedMarks* preserved_marks);
148   static void restore_preserved_marks();
149 
150   void flush_labs();
151   void flush_string_dedup_requests() { _string_dedup_requests.flush(); }
152 
153   void drain_stacks(bool totally_drain) {
154     drain_stacks_depth(totally_drain);
155   }
156  public:
157   void drain_stacks_cond_depth() {
158     if (claimed_stack_depth()->size() > _target_stack_size) {
159       drain_stacks_depth(false);
160     }
161   }
162   void drain_stacks_depth(bool totally_drain);
163 
164   bool stacks_empty() {
165     return claimed_stack_depth()->is_empty();
166   }
167 
168   inline void process_popped_location_depth(ScannerTask task);
169 
170   static bool should_scavenge(oop* p, bool check_to_space = false);
171   static bool should_scavenge(narrowOop* p, bool check_to_space = false);
172 
173   template <bool promote_immediately, class T>
174   void copy_and_push_safe_barrier(T* p);
175 
176   template <class T> inline void claim_or_forward_depth(T* p);
177 
178   TASKQUEUE_STATS_ONLY(inline void record_steal(ScannerTask task);)
179 
180   void push_contents(oop obj);
181 };
182 
183 #endif // SHARE_GC_PARALLEL_PSPROMOTIONMANAGER_HPP