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24 
25 #ifndef SHARE_GC_SHARED_PARALLELCLEANING_HPP
26 #define SHARE_GC_SHARED_PARALLELCLEANING_HPP
27 
28 #include "classfile/classLoaderDataGraph.hpp"
29 #include "code/codeCache.hpp"
30 #include "gc/shared/oopStorageParState.hpp"
31 #include "gc/shared/stringdedup/stringDedup.hpp"
32 #include "gc/shared/workgroup.hpp"
33 
34 class ParallelCleaningTask;
35 
36 class StringDedupCleaningTask : public AbstractGangTask {
37   StringDedupUnlinkOrOopsDoClosure _dedup_closure;
38 
39 public:
40   StringDedupCleaningTask(BoolObjectClosure* is_alive, OopClosure* keep_alive, bool resize_table);
41   ~StringDedupCleaningTask();
42 
43   void work(uint worker_id);
44 };
45 
46 class CodeCacheUnloadingTask {
47 
48   CodeCache::UnloadingScope _unloading_scope;
49   const bool                _unloading_occurred;
50   const uint                _num_workers;
51 
52   // Variables used to claim nmethods.
53   CompiledMethod* _first_nmethod;
54   CompiledMethod* volatile _claimed_nmethod;
55 
56 public:
57   CodeCacheUnloadingTask(uint num_workers, BoolObjectClosure* is_alive, bool unloading_occurred);
58   ~CodeCacheUnloadingTask();
59 
60 private:
61   static const int MaxClaimNmethods = 16;
62   void claim_nmethods(CompiledMethod** claimed_nmethods, int *num_claimed_nmethods);
63 
64 public:
65   // Cleaning and unloading of nmethods.
66   void work(uint worker_id);
67 };
68 
69 
70 class KlassCleaningTask : public StackObj {
71   volatile int                            _clean_klass_tree_claimed;
72   ClassLoaderDataGraphKlassIteratorAtomic _klass_iterator;
73 
74 public:
75   KlassCleaningTask();
76 
77 private:
78   bool claim_clean_klass_tree_task();
79   InstanceKlass* claim_next_klass();
80 
81 public:
82 
clean_klass(InstanceKlass * ik)83   void clean_klass(InstanceKlass* ik) {
84     ik->clean_weak_instanceklass_links();
85   }
86 
87   void work();
88 };
89 
90 #if INCLUDE_JVMCI
91 class JVMCICleaningTask : public StackObj {
92   volatile int       _cleaning_claimed;
93 
94 public:
95   JVMCICleaningTask();
96   // Clean JVMCI metadata handles.
97   void work(bool unloading_occurred);
98 
99 private:
100   bool claim_cleaning_task();
101 };
102 #endif
103 
104 // Do cleanup of some weakly held data in the same parallel task.
105 // Assumes a non-moving context.
106 class ParallelCleaningTask : public AbstractGangTask {
107 private:
108   bool                    _unloading_occurred;
109   StringDedupCleaningTask _string_dedup_task;
110   CodeCacheUnloadingTask  _code_cache_task;
111 #if INCLUDE_JVMCI
112   JVMCICleaningTask       _jvmci_cleaning_task;
113 #endif
114   KlassCleaningTask       _klass_cleaning_task;
115 
116 public:
117   // The constructor is run in the VMThread.
118   ParallelCleaningTask(BoolObjectClosure* is_alive,
119                        uint num_workers,
120                        bool unloading_occurred,
121                        bool resize_dedup_table);
122 
123   void work(uint worker_id);
124 };
125 
126 #endif // SHARE_GC_SHARED_PARALLELCLEANING_HPP
127