1 /*
2 * Copyright (c) 2001, 2015, 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.
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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
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23 */
24
25 #ifndef SHARE_VM_GC_PARALLEL_PARALLELSCAVENGEHEAP_HPP
26 #define SHARE_VM_GC_PARALLEL_PARALLELSCAVENGEHEAP_HPP
27
28 #include "gc/parallel/generationSizer.hpp"
29 #include "gc/parallel/objectStartArray.hpp"
30 #include "gc/parallel/psGCAdaptivePolicyCounters.hpp"
31 #include "gc/parallel/psOldGen.hpp"
32 #include "gc/parallel/psYoungGen.hpp"
33 #include "gc/shared/collectedHeap.hpp"
34 #include "gc/shared/collectorPolicy.hpp"
35 #include "gc/shared/gcPolicyCounters.hpp"
36 #include "gc/shared/gcWhen.hpp"
37 #include "gc/shared/strongRootsScope.hpp"
38 #include "memory/metaspace.hpp"
39 #include "utilities/ostream.hpp"
40
41 class AdjoiningGenerations;
42 class GCHeapSummary;
43 class GCTaskManager;
44 class PSAdaptiveSizePolicy;
45 class PSHeapSummary;
46
47 class ParallelScavengeHeap : public CollectedHeap {
48 friend class VMStructs;
49 private:
50 static PSYoungGen* _young_gen;
51 static PSOldGen* _old_gen;
52
53 // Sizing policy for entire heap
54 static PSAdaptiveSizePolicy* _size_policy;
55 static PSGCAdaptivePolicyCounters* _gc_policy_counters;
56
57 GenerationSizer* _collector_policy;
58
59 // Collection of generations that are adjacent in the
60 // space reserved for the heap.
61 AdjoiningGenerations* _gens;
62 unsigned int _death_march_count;
63
64 // The task manager
65 static GCTaskManager* _gc_task_manager;
66
67 void trace_heap(GCWhen::Type when, const GCTracer* tracer);
68
69 protected:
70 static inline size_t total_invocations();
71 HeapWord* allocate_new_tlab(size_t size);
72
73 inline bool should_alloc_in_eden(size_t size) const;
74 inline void death_march_check(HeapWord* const result, size_t size);
75 HeapWord* mem_allocate_old_gen(size_t size);
76
77 public:
78 ParallelScavengeHeap(GenerationSizer* policy) :
79 CollectedHeap(), _collector_policy(policy), _death_march_count(0) { }
80
81 // For use by VM operations
82 enum CollectionType {
83 Scavenge,
84 MarkSweep
85 };
86
87 virtual Name kind() const {
88 return CollectedHeap::ParallelScavengeHeap;
89 }
90
91 virtual const char* name() const {
92 return "Parallel";
93 }
94
95 virtual CollectorPolicy* collector_policy() const { return _collector_policy; }
96
97 static PSYoungGen* young_gen() { return _young_gen; }
98 static PSOldGen* old_gen() { return _old_gen; }
99
100 virtual PSAdaptiveSizePolicy* size_policy() { return _size_policy; }
101
102 static PSGCAdaptivePolicyCounters* gc_policy_counters() { return _gc_policy_counters; }
103
104 static ParallelScavengeHeap* heap();
105
106 static GCTaskManager* const gc_task_manager() { return _gc_task_manager; }
107
108 AdjoiningGenerations* gens() { return _gens; }
109
110 // Returns JNI_OK on success
111 virtual jint initialize();
112
113 void post_initialize();
114 void update_counters();
115
116 // The alignment used for the various areas
117 size_t space_alignment() { return _collector_policy->space_alignment(); }
118 size_t generation_alignment() { return _collector_policy->gen_alignment(); }
119
120 // Return the (conservative) maximum heap alignment
121 static size_t conservative_max_heap_alignment() {
122 return CollectorPolicy::compute_heap_alignment();
123 }
124
125 size_t capacity() const;
126 size_t used() const;
127
128 // Return "true" if all generations have reached the
129 // maximal committed limit that they can reach, without a garbage
130 // collection.
131 virtual bool is_maximal_no_gc() const;
132
133 // Return true if the reference points to an object that
134 // can be moved in a partial collection. For currently implemented
135 // generational collectors that means during a collection of
136 // the young gen.
137 virtual bool is_scavengable(const void* addr);
138
139 size_t max_capacity() const;
140
141 // Whether p is in the allocated part of the heap
142 bool is_in(const void* p) const;
143
144 bool is_in_reserved(const void* p) const;
145
146 bool is_in_young(oop p); // reserved part
147 bool is_in_old(oop p); // reserved part
148
149 // Memory allocation. "gc_time_limit_was_exceeded" will
150 // be set to true if the adaptive size policy determine that
151 // an excessive amount of time is being spent doing collections
152 // and caused a NULL to be returned. If a NULL is not returned,
153 // "gc_time_limit_was_exceeded" has an undefined meaning.
154 HeapWord* mem_allocate(size_t size, bool* gc_overhead_limit_was_exceeded);
155
156 // Allocation attempt(s) during a safepoint. It should never be called
157 // to allocate a new TLAB as this allocation might be satisfied out
158 // of the old generation.
159 HeapWord* failed_mem_allocate(size_t size);
160
161 // Support for System.gc()
162 void collect(GCCause::Cause cause);
163
164 // These also should be called by the vm thread at a safepoint (e.g., from a
165 // VM operation).
166 //
167 // The first collects the young generation only, unless the scavenge fails; it
168 // will then attempt a full gc. The second collects the entire heap; if
169 // maximum_compaction is true, it will compact everything and clear all soft
170 // references.
171 inline void invoke_scavenge();
172
173 // Perform a full collection
174 virtual void do_full_collection(bool clear_all_soft_refs);
175
176 bool supports_inline_contig_alloc() const { return !UseNUMA; }
177
178 HeapWord** top_addr() const { return !UseNUMA ? young_gen()->top_addr() : (HeapWord**)-1; }
179 HeapWord** end_addr() const { return !UseNUMA ? young_gen()->end_addr() : (HeapWord**)-1; }
180
181 void ensure_parsability(bool retire_tlabs);
182 void accumulate_statistics_all_tlabs();
183 void resize_all_tlabs();
184
185 bool supports_tlab_allocation() const { return true; }
186
187 size_t tlab_capacity(Thread* thr) const;
188 size_t tlab_used(Thread* thr) const;
189 size_t unsafe_max_tlab_alloc(Thread* thr) const;
190
191 // Can a compiler initialize a new object without store barriers?
192 // This permission only extends from the creation of a new object
193 // via a TLAB up to the first subsequent safepoint.
194 virtual bool can_elide_tlab_store_barriers() const {
195 return true;
196 }
197
198 virtual bool card_mark_must_follow_store() const {
199 return false;
200 }
201
202 // Return true if we don't we need a store barrier for
203 // initializing stores to an object at this address.
204 virtual bool can_elide_initializing_store_barrier(oop new_obj);
205
206 void object_iterate(ObjectClosure* cl);
207 void safe_object_iterate(ObjectClosure* cl) { object_iterate(cl); }
208
209 HeapWord* block_start(const void* addr) const;
210 size_t block_size(const HeapWord* addr) const;
211 bool block_is_obj(const HeapWord* addr) const;
212
213 jlong millis_since_last_gc();
214
215 void prepare_for_verify();
216 PSHeapSummary create_ps_heap_summary();
217 virtual void print_on(outputStream* st) const;
218 virtual void print_on_error(outputStream* st) const;
219 virtual void print_gc_threads_on(outputStream* st) const;
220 virtual void gc_threads_do(ThreadClosure* tc) const;
221 virtual void print_tracing_info() const;
222
223 void verify(VerifyOption option /* ignored */);
224
225 // Resize the young generation. The reserved space for the
226 // generation may be expanded in preparation for the resize.
227 void resize_young_gen(size_t eden_size, size_t survivor_size);
228
229 // Resize the old generation. The reserved space for the
230 // generation may be expanded in preparation for the resize.
231 void resize_old_gen(size_t desired_free_space);
232
233 // Save the tops of the spaces in all generations
234 void record_gen_tops_before_GC() PRODUCT_RETURN;
235
236 // Mangle the unused parts of all spaces in the heap
237 void gen_mangle_unused_area() PRODUCT_RETURN;
238
239 // Call these in sequential code around the processing of strong roots.
240 class ParStrongRootsScope : public MarkScope {
241 public:
242 ParStrongRootsScope();
243 ~ParStrongRootsScope();
244 };
245 };
246
247 // Simple class for storing info about the heap at the start of GC, to be used
248 // after GC for comparison/printing.
249 class PreGCValues {
250 public:
251 PreGCValues(ParallelScavengeHeap* heap) :
252 _heap_used(heap->used()),
253 _young_gen_used(heap->young_gen()->used_in_bytes()),
254 _old_gen_used(heap->old_gen()->used_in_bytes()),
255 _metadata_used(MetaspaceAux::used_bytes()) { };
256
257 size_t heap_used() const { return _heap_used; }
258 size_t young_gen_used() const { return _young_gen_used; }
259 size_t old_gen_used() const { return _old_gen_used; }
260 size_t metadata_used() const { return _metadata_used; }
261
262 private:
263 size_t _heap_used;
264 size_t _young_gen_used;
265 size_t _old_gen_used;
266 size_t _metadata_used;
267 };
268
269 #endif // SHARE_VM_GC_PARALLEL_PARALLELSCAVENGEHEAP_HPP