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24
25#ifndef SHARE_GC_G1_G1ROOTPROCESSOR_HPP
26#define SHARE_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 G1ParScanThreadState;
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_Management_oops_do,
62 G1RP_PS_SystemDictionary_oops_do,
63 G1RP_PS_ClassLoaderDataGraph_oops_do,
64 G1RP_PS_jvmti_oops_do,
65 G1RP_PS_CodeCache_oops_do,
66 AOT_ONLY(G1RP_PS_aot_oops_do COMMA)
67 JVMCI_ONLY(G1RP_PS_JVMCI_oops_do COMMA)
68 G1RP_PS_refProcessor_oops_do,
69 // Leave this one last.
70 G1RP_PS_NumElements
71 };
72
73 void worker_has_discovered_all_strong_classes();
74 void wait_until_all_strong_classes_discovered();
75
76 void process_java_roots(G1RootClosures* closures,
77 G1GCPhaseTimes* phase_times,
78 uint worker_i);
79
80 void process_vm_roots(G1RootClosures* closures,
81 G1GCPhaseTimes* phase_times,
82 uint worker_i);
83
84 void process_code_cache_roots(CodeBlobClosure* code_closure,
85 G1GCPhaseTimes* phase_times,
86 uint worker_i);
87
88public:
89 G1RootProcessor(G1CollectedHeap* g1h, uint n_workers);
90
91 // Apply correct closures from pss to the strongly and weakly reachable roots in the system
92 // in a single pass.
93 // Record and report timing measurements for sub phases using worker_id.
94 void evacuate_roots(G1ParScanThreadState* pss, uint worker_id);
95
96 // Apply oops, clds and blobs to all strongly reachable roots in the system
97 void process_strong_roots(OopClosure* oops,
98 CLDClosure* clds,
99 CodeBlobClosure* blobs);
100
101 // Apply oops, clds and blobs to strongly and weakly reachable roots in the system
102 void process_all_roots(OopClosure* oops,
103 CLDClosure* clds,
104 CodeBlobClosure* blobs);
105
106 // Number of worker threads used by the root processor.
107 uint n_workers() const;
108};
109
110#endif // SHARE_GC_G1_G1ROOTPROCESSOR_HPP
111