1 /*
2 * Copyright (c) 2021, Red Hat, Inc. All rights reserved.
3 * Copyright Amazon.com Inc. or its affiliates. All Rights Reserved.
4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5 *
6 * This code is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 only, as
8 * published by the Free Software Foundation.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 *
24 */
25
26 #ifndef SHARE_GC_SHENANDOAH_SHENANDOAHCONCURRENTGC_HPP
27 #define SHARE_GC_SHENANDOAH_SHENANDOAHCONCURRENTGC_HPP
28
29 #include "gc/shared/gcCause.hpp"
30 #include "gc/shenandoah/shenandoahConcurrentMark.hpp"
31 #include "gc/shenandoah/shenandoahGC.hpp"
32 #include "gc/shenandoah/shenandoahHeap.hpp"
33
34 class ShenandoahGeneration;
35
36 class VM_ShenandoahInitMark;
37 class VM_ShenandoahFinalMarkStartEvac;
38 class VM_ShenandoahInitUpdateRefs;
39 class VM_ShenandoahFinalUpdateRefs;
40
41 class ShenandoahConcurrentGC : public ShenandoahGC {
42 friend class VM_ShenandoahInitMark;
43 friend class VM_ShenandoahFinalMarkStartEvac;
44 friend class VM_ShenandoahInitUpdateRefs;
45 friend class VM_ShenandoahFinalUpdateRefs;
46 friend class VM_ShenandoahFinalRoots;
47
48 protected:
49 ShenandoahConcurrentMark _mark;
50
51 private:
52 ShenandoahDegenPoint _degen_point;
53 bool _abbreviated;
54 const bool _do_old_gc_bootstrap;
55
56 protected:
57 ShenandoahGeneration* const _generation;
58
59 public:
60 ShenandoahConcurrentGC(ShenandoahGeneration* generation, bool do_old_gc_bootstrap);
61 bool collect(GCCause::Cause cause) override;
62 ShenandoahDegenPoint degen_point() const;
63
64 // Return true if this cycle found enough immediate garbage to skip evacuation
65 bool abbreviated() const { return _abbreviated; }
66
67 private:
68 // Entry points to STW GC operations, these cause a related safepoint, that then
69 // call the entry method below
70 void vmop_entry_init_mark();
71
72 protected:
73 void vmop_entry_final_mark();
74 void vmop_entry_final_roots();
75
76 private:
77 void vmop_entry_init_updaterefs();
78 void vmop_entry_final_updaterefs();
79
80 // Entry methods to normally STW GC operations. These set up logging, monitoring
81 // and workers for net VM operation
82 void entry_init_mark();
83 void entry_final_mark();
84 void entry_init_updaterefs();
85 void entry_final_updaterefs();
86 void entry_final_roots();
87
88 // Entry methods to normally concurrent GC operations. These set up logging, monitoring
89 // for concurrent operation.
90 void entry_reset();
91 void entry_mark_roots();
92 void entry_scan_remembered_set();
93
94 protected:
95 void entry_mark();
96 void entry_thread_roots();
97 void entry_weak_refs();
98 void entry_weak_roots();
99 void entry_class_unloading();
100 void entry_strong_roots();
101 void entry_cleanup_early();
102
103 private:
104 void entry_evacuate();
105 void entry_update_thread_roots();
106 void entry_updaterefs();
107
108 void entry_cleanup_complete();
109
110 // Called when the collection set is empty, but the generational mode has regions to promote in place
111 void entry_promote_in_place();
112
113 // Actual work for the phases
114 void op_reset();
115 void op_init_mark();
116 void op_mark_roots();
117 void op_mark();
118 void op_thread_roots();
119 void op_weak_refs();
120 void op_weak_roots();
121 void op_class_unloading();
122 void op_strong_roots();
123 void op_cleanup_early();
124 void op_evacuate();
125 void op_init_updaterefs();
126 void op_updaterefs();
127 void op_update_thread_roots();
128 void op_final_updaterefs();
129 void op_final_roots();
130
131 void op_cleanup_complete();
132
133 protected:
134 virtual void op_final_mark();
135
136 private:
137 void start_mark();
138
139 static bool has_in_place_promotions(ShenandoahHeap* heap) ;
140
141 // Messages for GC trace events, they have to be immortal for
142 // passing around the logging/tracing systems
143 const char* init_mark_event_message() const;
144 const char* final_mark_event_message() const;
145 const char* final_roots_event_message() const;
146 const char* conc_mark_event_message() const;
147 const char* conc_reset_event_message() const;
148 const char* conc_weak_refs_event_message() const;
149 const char* conc_weak_roots_event_message() const;
150 const char* conc_cleanup_event_message() const;
151
152 protected:
153 // Check GC cancellation and abort concurrent GC
154 bool check_cancellation_and_abort(ShenandoahDegenPoint point);
155 };
156
157 #endif // SHARE_GC_SHENANDOAH_SHENANDOAHCONCURRENTGC_HPP