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24
25#ifndef SHARE_GC_SHARED_WEAKPROCESSOR_HPP
26#define SHARE_GC_SHARED_WEAKPROCESSOR_HPP
27
28#include "gc/shared/oopStorageParState.hpp"
29#include "gc/shared/workgroup.hpp"
30#include "memory/allocation.hpp"
31
32class WeakProcessorPhaseTimes;
33class WorkGang;
34
35// Helper class to aid in root scanning and cleaning of weak oops in the VM.
36//
37// New containers of weak oops added to this class will automatically
38// be cleaned by all GCs, including the young generation GCs.
39class WeakProcessor : AllStatic {
40public:
41 // Visit all oop*s and apply the keep_alive closure if the referenced
42 // object is considered alive by the is_alive closure, otherwise do some
43 // container specific cleanup of element holding the oop.
44 static void weak_oops_do(BoolObjectClosure* is_alive, OopClosure* keep_alive);
45
46 // Visit all oop*s and apply the given closure.
47 static void oops_do(OopClosure* closure);
48
49 // Parallel version. Uses ergo_workers(), active workers, and
50 // phase_time's max_threads to determine the number of threads to use.
51 // IsAlive must be derived from BoolObjectClosure.
52 // KeepAlive must be derived from OopClosure.
53 template<typename IsAlive, typename KeepAlive>
54 static void weak_oops_do(WorkGang* workers,
55 IsAlive* is_alive,
56 KeepAlive* keep_alive,
57 WeakProcessorPhaseTimes* phase_times);
58
59 // Convenience parallel version. Uses ergo_workers() and active workers
60 // to determine the number of threads to run. Implicitly logs phase times.
61 // IsAlive must be derived from BoolObjectClosure.
62 // KeepAlive must be derived from OopClosure.
63 template<typename IsAlive, typename KeepAlive>
64 static void weak_oops_do(WorkGang* workers,
65 IsAlive* is_alive,
66 KeepAlive* keep_alive,
67 uint indent_log);
68
69 static uint ergo_workers(uint max_workers);
70 class Task;
71
72private:
73 class GangTask;
74};
75
76class WeakProcessor::Task {
77 typedef OopStorage::ParState<false, false> StorageState;
78
79 WeakProcessorPhaseTimes* _phase_times;
80 uint _nworkers;
81 SubTasksDone _serial_phases_done;
82 StorageState* _storage_states;
83
84 void initialize();
85
86public:
87 Task(uint nworkers); // No time tracking.
88 Task(WeakProcessorPhaseTimes* phase_times, uint nworkers);
89 ~Task();
90
91 template<typename IsAlive, typename KeepAlive>
92 void work(uint worker_id, IsAlive* is_alive, KeepAlive* keep_alive);
93};
94
95#endif // SHARE_GC_SHARED_WEAKPROCESSOR_HPP
96