1/*
2 * Copyright (c) 2001, 2019, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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5 * This code is free software; you can redistribute it and/or modify it
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24
25#ifndef SHARE_GC_G1_G1CONCURRENTMARKTHREAD_HPP
26#define SHARE_GC_G1_G1CONCURRENTMARKTHREAD_HPP
27
28#include "gc/shared/concurrentGCPhaseManager.hpp"
29#include "gc/shared/concurrentGCThread.hpp"
30
31class G1ConcurrentMark;
32class G1Policy;
33
34// The concurrent mark thread triggers the various steps of the concurrent marking
35// cycle, including various marking cleanup.
36class G1ConcurrentMarkThread: public ConcurrentGCThread {
37 friend class VMStructs;
38
39 double _vtime_start; // Initial virtual time.
40 double _vtime_accum; // Accumulated virtual time.
41 double _vtime_mark_accum;
42
43 G1ConcurrentMark* _cm;
44
45 enum State {
46 Idle,
47 Started,
48 InProgress
49 };
50
51 volatile State _state;
52
53 // WhiteBox testing support.
54 ConcurrentGCPhaseManager::Stack _phase_manager_stack;
55
56 void sleep_before_next_cycle();
57 // Delay marking to meet MMU.
58 void delay_to_keep_mmu(G1Policy* g1_policy, bool remark);
59 double mmu_sleep_time(G1Policy* g1_policy, bool remark);
60
61 void run_service();
62 void stop_service();
63
64 public:
65 // Constructor
66 G1ConcurrentMarkThread(G1ConcurrentMark* cm);
67
68 // Total virtual time so far for this thread and concurrent marking tasks.
69 double vtime_accum();
70 // Marking virtual time so far this thread and concurrent marking tasks.
71 double vtime_mark_accum();
72
73 G1ConcurrentMark* cm() { return _cm; }
74
75 void set_idle() { assert(_state != Started, "must not be starting a new cycle"); _state = Idle; }
76 bool idle() { return _state == Idle; }
77 void set_started() { assert(_state == Idle, "cycle in progress"); _state = Started; }
78 bool started() { return _state == Started; }
79 void set_in_progress() { assert(_state == Started, "must be starting a cycle"); _state = InProgress; }
80 bool in_progress() { return _state == InProgress; }
81
82 // Returns true from the moment a marking cycle is
83 // initiated (during the initial-mark pause when started() is set)
84 // to the moment when the cycle completes (just after the next
85 // marking bitmap has been cleared and in_progress() is
86 // cleared). While during_cycle() is true we will not start another cycle
87 // so that cycles do not overlap. We cannot use just in_progress()
88 // as the CM thread might take some time to wake up before noticing
89 // that started() is set and set in_progress().
90 bool during_cycle() { return !idle(); }
91
92 // WhiteBox testing support.
93 bool request_concurrent_phase(const char* phase);
94
95 ConcurrentGCPhaseManager::Stack* phase_manager_stack() {
96 return &_phase_manager_stack;
97 }
98};
99
100#endif // SHARE_GC_G1_G1CONCURRENTMARKTHREAD_HPP
101