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).
 14  *
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 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
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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/g1HeapRegion.hpp"
 30 #include "memory/allocation.hpp"
 31 
 32 class G1CollectedHeap;
 33 class G1CMBitMap;
 34 class G1FullCollector;
 35 class G1FullGCCompactionPoint;
 36 class HeapRegion;
 37 
 38 // Determines the regions in the heap that should be part of the compaction and
 39 // distributes them among the compaction queues in round-robin fashion.
 40 class G1DetermineCompactionQueueClosure : public HeapRegionClosure {
 41   G1CollectedHeap* _g1h;
 42   G1FullCollector* _collector;
 43   uint _cur_worker;
 44 
 45   inline void free_empty_humongous_region(HeapRegion* hr);
 46 
 47   inline bool should_compact(HeapRegion* hr) const;
 48 
 49   // Returns the current worker id to assign a compaction point to, and selects
 50   // the next one round-robin style.
 51   inline uint next_worker();
 52 
 53   inline G1FullGCCompactionPoint* next_compaction_point();
 54 
 55   inline void add_to_compaction_queue(HeapRegion* hr);
 56 
 57 public:
 58   G1DetermineCompactionQueueClosure(G1FullCollector* collector);
 59 
 60   inline bool do_heap_region(HeapRegion* hr) override;
 61 };
 62 
 63 class G1FullGCPrepareTask : public G1FullGCTask {
 64   volatile bool     _has_free_compaction_targets;
 65   HeapRegionClaimer _hrclaimer;
 66 
 67   void set_has_free_compaction_targets();
 68 
 69 public:
 70   G1FullGCPrepareTask(G1FullCollector* collector);
 71   void work(uint worker_id);
 72   // After the Prepare phase, are there any unused (empty) regions (compaction
 73   // targets) at the end of any compaction queues?
 74   bool has_free_compaction_targets();
 75 
 76 private:
 77   class G1CalculatePointersClosure : public HeapRegionClosure {
 78     G1CollectedHeap* _g1h;
 79     G1FullCollector* _collector;
 80     G1CMBitMap* _bitmap;
 81     G1FullGCCompactionPoint* _cp;
 82 
 83     void prepare_for_compaction(HeapRegion* hr);
 84 
 85   public:
 86     G1CalculatePointersClosure(G1FullCollector* collector,
 87                                G1FullGCCompactionPoint* cp);
 88 
 89     bool do_heap_region(HeapRegion* hr);
 90   };
 91 
 92   class G1PrepareCompactLiveClosure : public StackObj {
 93     G1FullGCCompactionPoint* _cp;
 94 
 95   public:
 96     G1PrepareCompactLiveClosure(G1FullGCCompactionPoint* cp);
 97     size_t apply(oop object);
 98   };
 99 };
100 
101 // Closure to re-prepare objects in the serial compaction point queue regions for
102 // serial compaction.
103 class G1SerialRePrepareClosure : public StackObj {
104   G1FullGCCompactionPoint* _cp;
105   HeapWord* _dense_prefix_top;
106 
107 public:
108   G1SerialRePrepareClosure(G1FullGCCompactionPoint* hrcp, HeapWord* dense_prefix_top) :
109     _cp(hrcp),
110     _dense_prefix_top(dense_prefix_top) { }
111 
112   inline size_t apply(oop obj);
113 };
114 
115 #endif // SHARE_GC_G1_G1FULLGCPREPARETASK_HPP