g1RootProcessor.hpp revision 12408:777aaa19c4b1 
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24
25#ifndef SHARE_VM_GC_G1_G1ROOTPROCESSOR_HPP
26#define SHARE_VM_GC_G1_G1ROOTPROCESSOR_HPP
27
28#include "gc/shared/strongRootsScope.hpp"
29#include "memory/allocation.hpp"
30#include "runtime/mutex.hpp"
31
32class CLDClosure;
33class CodeBlobClosure;
34class G1CollectedHeap;
35class G1EvacuationRootClosures;
36class G1GCPhaseTimes;
37class G1ParPushHeapRSClosure;
38class G1RootClosures;
39class Monitor;
40class OopClosure;
41class SubTasksDone;
42
43// Scoped object to assist in applying oop, CLD and code blob closures to
44// root locations. Handles claiming of different root scanning tasks
45// and takes care of global state for root scanning via a StrongRootsScope.
46// In the parallel case there is a shared G1RootProcessor object where all
47// worker thread call the process_roots methods.
48class G1RootProcessor : public StackObj {
49  G1CollectedHeap* _g1h;
50  SubTasksDone _process_strong_tasks;
51  StrongRootsScope _srs;
52
53  // Used to implement the Thread work barrier.
54  Monitor _lock;
55  volatile jint _n_workers_discovered_strong_classes;
56
57  enum G1H_process_roots_tasks {
58    G1RP_PS_Universe_oops_do,
59    G1RP_PS_JNIHandles_oops_do,
60    G1RP_PS_ObjectSynchronizer_oops_do,
61    G1RP_PS_FlatProfiler_oops_do,
62    G1RP_PS_Management_oops_do,
63    G1RP_PS_SystemDictionary_oops_do,
64    G1RP_PS_ClassLoaderDataGraph_oops_do,
65    G1RP_PS_jvmti_oops_do,
66    G1RP_PS_CodeCache_oops_do,
67    G1RP_PS_aot_oops_do,
68    G1RP_PS_filter_satb_buffers,
69    G1RP_PS_refProcessor_oops_do,
70    // Leave this one last.
71    G1RP_PS_NumElements
72  };
73
74  void worker_has_discovered_all_strong_classes();
75  void wait_until_all_strong_classes_discovered();
76
77  void process_all_roots(OopClosure* oops,
78                         CLDClosure* clds,
79                         CodeBlobClosure* blobs,
80                         bool process_string_table);
81
82  void process_java_roots(G1RootClosures* closures,
83                          G1GCPhaseTimes* phase_times,
84                          uint worker_i);
85
86  void process_vm_roots(G1RootClosures* closures,
87                        G1GCPhaseTimes* phase_times,
88                        uint worker_i);
89
90  void process_string_table_roots(G1RootClosures* closures,
91                                  G1GCPhaseTimes* phase_times,
92                                  uint worker_i);
93
94  void process_code_cache_roots(CodeBlobClosure* code_closure,
95                                G1GCPhaseTimes* phase_times,
96                                uint worker_i);
97
98public:
99  G1RootProcessor(G1CollectedHeap* g1h, uint n_workers);
100
101  // Apply closures to the strongly and weakly reachable roots in the system
102  // in a single pass.
103  // Record and report timing measurements for sub phases using the worker_i
104  void evacuate_roots(G1EvacuationRootClosures* closures, uint worker_i);
105
106  // Apply oops, clds and blobs to all strongly reachable roots in the system
107  void process_strong_roots(OopClosure* oops,
108                            CLDClosure* clds,
109                            CodeBlobClosure* blobs);
110
111  // Apply oops, clds and blobs to strongly and weakly reachable roots in the system
112  void process_all_roots(OopClosure* oops,
113                         CLDClosure* clds,
114                         CodeBlobClosure* blobs);
115
116  // Apply oops, clds and blobs to strongly and weakly reachable roots in the system,
117  // the only thing different from process_all_roots is that we skip the string table
118  // to avoid keeping every string live when doing class unloading.
119  void process_all_roots_no_string_table(OopClosure* oops,
120                                         CLDClosure* clds,
121                                         CodeBlobClosure* blobs);
122
123  // Number of worker threads used by the root processor.
124  uint n_workers() const;
125};
126
127#endif // SHARE_VM_GC_G1_G1ROOTPROCESSOR_HPP
128