g1RootProcessor.hpp revision 13544:61c0ae8bee4e 
1/*
2 * Copyright (c) 2015, 2017, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
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 G1RootClosures;
38class Monitor;
39class OopClosure;
40class SubTasksDone;
41
42// Scoped object to assist in applying oop, CLD and code blob closures to
43// root locations. Handles claiming of different root scanning tasks
44// and takes care of global state for root scanning via a StrongRootsScope.
45// In the parallel case there is a shared G1RootProcessor object where all
46// worker thread call the process_roots methods.
47class G1RootProcessor : public StackObj {
48  G1CollectedHeap* _g1h;
49  SubTasksDone _process_strong_tasks;
50  StrongRootsScope _srs;
51
52  // Used to implement the Thread work barrier.
53  Monitor _lock;
54  volatile jint _n_workers_discovered_strong_classes;
55
56  enum G1H_process_roots_tasks {
57    G1RP_PS_Universe_oops_do,
58    G1RP_PS_JNIHandles_oops_do,
59    G1RP_PS_ObjectSynchronizer_oops_do,
60    G1RP_PS_Management_oops_do,
61    G1RP_PS_SystemDictionary_oops_do,
62    G1RP_PS_ClassLoaderDataGraph_oops_do,
63    G1RP_PS_jvmti_oops_do,
64    G1RP_PS_CodeCache_oops_do,
65    G1RP_PS_aot_oops_do,
66    G1RP_PS_filter_satb_buffers,
67    G1RP_PS_refProcessor_oops_do,
68    // Leave this one last.
69    G1RP_PS_NumElements
70  };
71
72  void worker_has_discovered_all_strong_classes();
73  void wait_until_all_strong_classes_discovered();
74
75  void process_all_roots(OopClosure* oops,
76                         CLDClosure* clds,
77                         CodeBlobClosure* blobs,
78                         bool process_string_table);
79
80  void process_java_roots(G1RootClosures* closures,
81                          G1GCPhaseTimes* phase_times,
82                          uint worker_i);
83
84  void process_vm_roots(G1RootClosures* closures,
85                        G1GCPhaseTimes* phase_times,
86                        uint worker_i);
87
88  void process_string_table_roots(G1RootClosures* closures,
89                                  G1GCPhaseTimes* phase_times,
90                                  uint worker_i);
91
92  void process_code_cache_roots(CodeBlobClosure* code_closure,
93                                G1GCPhaseTimes* phase_times,
94                                uint worker_i);
95
96public:
97  G1RootProcessor(G1CollectedHeap* g1h, uint n_workers);
98
99  // Apply closures to the strongly and weakly reachable roots in the system
100  // in a single pass.
101  // Record and report timing measurements for sub phases using the worker_i
102  void evacuate_roots(G1EvacuationRootClosures* closures, uint worker_i);
103
104  // Apply oops, clds and blobs to all strongly reachable roots in the system
105  void process_strong_roots(OopClosure* oops,
106                            CLDClosure* clds,
107                            CodeBlobClosure* blobs);
108
109  // Apply oops, clds and blobs to strongly and weakly reachable roots in the system
110  void process_all_roots(OopClosure* oops,
111                         CLDClosure* clds,
112                         CodeBlobClosure* blobs);
113
114  // Apply oops, clds and blobs to strongly and weakly reachable roots in the system,
115  // the only thing different from process_all_roots is that we skip the string table
116  // to avoid keeping every string live when doing class unloading.
117  void process_all_roots_no_string_table(OopClosure* oops,
118                                         CLDClosure* clds,
119                                         CodeBlobClosure* blobs);
120
121  // Number of worker threads used by the root processor.
122  uint n_workers() const;
123};
124
125#endif // SHARE_VM_GC_G1_G1ROOTPROCESSOR_HPP
126