1 /*
2 * Copyright (c) 2017, 2018, 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.
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23 */
24
25 #ifndef SHARE_VM_GC_CMS_CMSHEAP_HPP
26 #define SHARE_VM_GC_CMS_CMSHEAP_HPP
27
28 #include "gc/cms/concurrentMarkSweepGeneration.hpp"
29 #include "gc/cms/parNewGeneration.hpp"
30 #include "gc/shared/collectedHeap.hpp"
31 #include "gc/shared/gcCause.hpp"
32 #include "gc/shared/genCollectedHeap.hpp"
33 #include "gc/shared/oopStorageParState.hpp"
34 #include "utilities/growableArray.hpp"
35
36 class CLDClosure;
37 class GenCollectorPolicy;
38 class GCMemoryManager;
39 class MemoryPool;
40 class OopsInGenClosure;
41 class outputStream;
42 class StrongRootsScope;
43 class ThreadClosure;
44 class WorkGang;
45
46 class CMSHeap : public GenCollectedHeap {
47 public:
48 CMSHeap(GenCollectorPolicy *policy);
49
50 // Returns JNI_OK on success
51 virtual jint initialize();
52 virtual CardTableRS* create_rem_set(const MemRegion& reserved_region);
53
54 // Convenience function to be used in situations where the heap type can be
55 // asserted to be this type.
56 static CMSHeap* heap();
57
58 virtual Name kind() const {
59 return CollectedHeap::CMS;
60 }
61
62 virtual const char* name() const {
63 return "Concurrent Mark Sweep";
64 }
65
66 WorkGang* workers() const { return _workers; }
67
68 virtual void print_gc_threads_on(outputStream* st) const;
69 virtual void gc_threads_do(ThreadClosure* tc) const;
70 virtual void print_on_error(outputStream* st) const;
71
72 // Perform a full collection of the heap; intended for use in implementing
73 // "System.gc". This implies as full a collection as the CollectedHeap
74 // supports. Caller does not hold the Heap_lock on entry.
75 void collect(GCCause::Cause cause);
76
77 void stop();
78 void safepoint_synchronize_begin();
79 void safepoint_synchronize_end();
80
81 virtual GrowableArray<GCMemoryManager*> memory_managers();
82 virtual GrowableArray<MemoryPool*> memory_pools();
83
84 // If "young_gen_as_roots" is false, younger generations are
85 // not scanned as roots; in this case, the caller must be arranging to
86 // scan the younger generations itself. (For example, a generation might
87 // explicitly mark reachable objects in younger generations, to avoid
88 // excess storage retention.)
89 void cms_process_roots(StrongRootsScope* scope,
90 bool young_gen_as_roots,
91 ScanningOption so,
92 bool only_strong_roots,
93 OopsInGenClosure* root_closure,
94 CLDClosure* cld_closure,
95 OopStorage::ParState<false, false>* par_state_string = NULL);
96
97 GCMemoryManager* old_manager() const { return _old_manager; }
98
99 ParNewGeneration* young_gen() const {
100 assert(_young_gen->kind() == Generation::ParNew, "Wrong generation type");
101 return static_cast<ParNewGeneration*>(_young_gen);
102 }
103
104 ConcurrentMarkSweepGeneration* old_gen() const {
105 assert(_old_gen->kind() == Generation::ConcurrentMarkSweep, "Wrong generation kind");
106 return static_cast<ConcurrentMarkSweepGeneration*>(_old_gen);
107 }
108
109 // Apply "cur->do_oop" or "older->do_oop" to all the oops in objects
110 // allocated since the last call to save_marks in the young generation.
111 // The "cur" closure is applied to references in the younger generation
112 // at "level", and the "older" closure to older generations.
113 template <typename OopClosureType1, typename OopClosureType2>
114 void oop_since_save_marks_iterate(OopClosureType1* cur,
115 OopClosureType2* older);
116
117 private:
118 WorkGang* _workers;
119 MemoryPool* _eden_pool;
120 MemoryPool* _survivor_pool;
121 MemoryPool* _old_pool;
122
123 virtual void gc_prologue(bool full);
124 virtual void gc_epilogue(bool full);
125
126 virtual void initialize_serviceability();
127
128 // Accessor for memory state verification support
129 NOT_PRODUCT(
130 virtual size_t skip_header_HeapWords() { return CMSCollector::skip_header_HeapWords(); }
131 )
132
133 // Returns success or failure.
134 bool create_cms_collector();
135
136 // In support of ExplicitGCInvokesConcurrent functionality
137 bool should_do_concurrent_full_gc(GCCause::Cause cause);
138
139 void collect_mostly_concurrent(GCCause::Cause cause);
140 };
141
142 #endif // SHARE_VM_GC_CMS_CMSHEAP_HPP