1 /*
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  3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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  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  *
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 18  *
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 24 
 25 #ifndef SHARE_GC_G1_G1FULLGCPREPARETASK_HPP
 26 #define SHARE_GC_G1_G1FULLGCPREPARETASK_HPP
 27 
 28 #include "gc/g1/g1FullGCTask.hpp"
 29 #include "gc/g1/heapRegion.hpp"
 30 #include "memory/allocation.hpp"
 31 
 32 class G1CollectedHeap;
 33 class G1CMBitMap;
 34 class G1FullCollector;
 35 class SlidingForwarding;
 36 class G1FullGCCompactionPoint;
 37 class HeapRegion;
 38 
 39 // Determines the regions in the heap that should be part of the compaction and
 40 // distributes them among the compaction queues in round-robin fashion.
 41 class G1DetermineCompactionQueueClosure : public HeapRegionClosure {
 42   G1CollectedHeap* _g1h;
 43   G1FullCollector* _collector;
 44   uint _cur_worker;
 45 
 46   template<bool is_humongous>
 47   inline void free_pinned_region(HeapRegion* hr);
 48 
 49   inline bool should_compact(HeapRegion* hr) const;
 50 
 51   // Returns the current worker id to assign a compaction point to, and selects
 52   // the next one round-robin style.
 53   inline uint next_worker();
 54 
 55   inline G1FullGCCompactionPoint* next_compaction_point();
 56 
 57   inline void add_to_compaction_queue(HeapRegion* hr);
 58 
 59 public:
 60   G1DetermineCompactionQueueClosure(G1FullCollector* collector);
 61 
 62   inline bool do_heap_region(HeapRegion* hr) override;
 63 };
 64 
 65 class G1FullGCPrepareTask : public G1FullGCTask {
 66   volatile bool     _has_free_compaction_targets;
 67   HeapRegionClaimer _hrclaimer;
 68 
 69   void set_has_free_compaction_targets();
 70 
 71 public:
 72   G1FullGCPrepareTask(G1FullCollector* collector);
 73   void work(uint worker_id);
 74   // After the Prepare phase, are there any unused (empty) regions (compaction
 75   // targets) at the end of any compaction queues?
 76   bool has_free_compaction_targets();
 77 
 78 private:
 79   class G1CalculatePointersClosure : public HeapRegionClosure {
 80     G1CollectedHeap* _g1h;
 81     G1FullCollector* _collector;
 82     G1CMBitMap* _bitmap;
 83     G1FullGCCompactionPoint* _cp;
 84 
 85     void prepare_for_compaction(HeapRegion* hr);
 86 
 87   public:
 88     G1CalculatePointersClosure(G1FullCollector* collector,
 89                                G1FullGCCompactionPoint* cp);
 90 
 91     bool do_heap_region(HeapRegion* hr);
 92   };
 93 
 94   class G1ResetMetadataClosure : public HeapRegionClosure {
 95     G1CollectedHeap* _g1h;
 96     G1FullCollector* _collector;
 97 
 98     void reset_region_metadata(HeapRegion* hr);
 99 
100   public:
101     G1ResetMetadataClosure(G1FullCollector* collector);
102 
103     bool do_heap_region(HeapRegion* hr);
104   };
105 
106   class G1PrepareCompactLiveClosure : public StackObj {
107     G1FullGCCompactionPoint* _cp;
108     SlidingForwarding* const _forwarding;
109 
110   public:
111     G1PrepareCompactLiveClosure(G1FullGCCompactionPoint* cp);
112     size_t apply(oop object);
113   };
114 };
115 
116 // Closure to re-prepare objects in the serial compaction point queue regions for
117 // serial compaction.
118 //class G1SerialRePrepareClosure : public StackObj {
119 //  G1FullGCCompactionPoint* _cp;
120 //  HeapRegion* _current;
121 //
122 //public:
123 //  G1SerialRePrepareClosure(G1FullGCCompactionPoint* hrcp, HeapRegion* hr) :
124 //    _cp(hrcp),
125 //    _current(hr) { }
126 //
127 //  inline size_t apply(oop obj);
128 //};
129 
130 #endif // SHARE_GC_G1_G1FULLGCPREPARETASK_HPP