1 /*
2 * Copyright (c) 2001, 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
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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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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/cardTableBarrierSet.hpp"
34 #include "gc/shared/collectedHeap.hpp"
35 #include "gc/shared/collectorPolicy.hpp"
36 #include "gc/shared/gcPolicyCounters.hpp"
37 #include "gc/shared/gcWhen.hpp"
38 #include "gc/shared/softRefPolicy.hpp"
39 #include "gc/shared/strongRootsScope.hpp"
40 #include "memory/metaspace.hpp"
41 #include "utilities/growableArray.hpp"
42 #include "utilities/ostream.hpp"
43
44 class AdjoiningGenerations;
45 class GCHeapSummary;
46 class GCTaskManager;
47 class MemoryManager;
48 class MemoryPool;
49 class PSAdaptiveSizePolicy;
50 class PSCardTable;
51 class PSHeapSummary;
52
53 class ParallelScavengeHeap : public CollectedHeap {
54 friend class VMStructs;
55 private:
56 static PSYoungGen* _young_gen;
57 static PSOldGen* _old_gen;
58
59 // Sizing policy for entire heap
60 static PSAdaptiveSizePolicy* _size_policy;
61 static PSGCAdaptivePolicyCounters* _gc_policy_counters;
62
63 GenerationSizer* _collector_policy;
64
65 // is the heap backed by two different memories?
66 bool _is_hetero_heap;
67
68 SoftRefPolicy _soft_ref_policy;
69
70 // Collection of generations that are adjacent in the
71 // space reserved for the heap.
72 AdjoiningGenerations* _gens;
73 unsigned int _death_march_count;
74
75 // The task manager
76 static GCTaskManager* _gc_task_manager;
77
78 GCMemoryManager* _young_manager;
79 GCMemoryManager* _old_manager;
80
81 MemoryPool* _eden_pool;
82 MemoryPool* _survivor_pool;
83 MemoryPool* _old_pool;
84
85 virtual void initialize_serviceability();
86
87 void trace_heap(GCWhen::Type when, const GCTracer* tracer);
88
89 protected:
90 static inline size_t total_invocations();
91 HeapWord* allocate_new_tlab(size_t min_size, size_t requested_size, size_t* actual_size);
92
93 inline bool should_alloc_in_eden(size_t size) const;
94 inline void death_march_check(HeapWord* const result, size_t size);
95 HeapWord* mem_allocate_old_gen(size_t size);
96
97 public:
98 ParallelScavengeHeap(GenerationSizer* policy) :
99 CollectedHeap(), _collector_policy(policy), _is_hetero_heap(false), _death_march_count(0) { }
100
101 // For use by VM operations
102 enum CollectionType {
103 Scavenge,
104 MarkSweep
105 };
106
107 virtual Name kind() const {
108 return CollectedHeap::Parallel;
109 }
110
111 virtual const char* name() const {
112 return "Parallel";
113 }
114
115 virtual CollectorPolicy* collector_policy() const { return _collector_policy; }
116
117 virtual SoftRefPolicy* soft_ref_policy() { return &_soft_ref_policy; }
118
119 virtual GrowableArray<GCMemoryManager*> memory_managers();
120 virtual GrowableArray<MemoryPool*> memory_pools();
121
122 static PSYoungGen* young_gen() { return _young_gen; }
123 static PSOldGen* old_gen() { return _old_gen; }
124
125 virtual PSAdaptiveSizePolicy* size_policy() { return _size_policy; }
126
127 static PSGCAdaptivePolicyCounters* gc_policy_counters() { return _gc_policy_counters; }
128
129 static ParallelScavengeHeap* heap();
130
131 static GCTaskManager* const gc_task_manager() { return _gc_task_manager; }
132
133 CardTableBarrierSet* barrier_set();
134 PSCardTable* card_table();
135
136 AdjoiningGenerations* gens() { return _gens; }
137
138 // Returns JNI_OK on success
139 virtual jint initialize();
140
141 void post_initialize();
142 void update_counters();
143
144 // The alignment used for the various areas
145 size_t space_alignment() { return _collector_policy->space_alignment(); }
146 size_t generation_alignment() { return _collector_policy->gen_alignment(); }
147
148 // Return the (conservative) maximum heap alignment
149 static size_t conservative_max_heap_alignment() {
150 return CollectorPolicy::compute_heap_alignment();
151 }
152
153 // is the heap backed by two different memories?
154 bool is_hetero_heap() { return _is_hetero_heap; }
155
156 size_t capacity() const;
157 size_t used() const;
158
159 // Return "true" if all generations have reached the
160 // maximal committed limit that they can reach, without a garbage
161 // collection.
162 virtual bool is_maximal_no_gc() const;
163
164 // Return true if the reference points to an object that
165 // can be moved in a partial collection. For currently implemented
166 // generational collectors that means during a collection of
167 // the young gen.
168 virtual bool is_scavengable(oop obj);
169 virtual void register_nmethod(nmethod* nm);
170 virtual void verify_nmethod(nmethod* nmethod);
171
172 size_t max_capacity() const;
173
174 // Whether p is in the allocated part of the heap
175 bool is_in(const void* p) const;
176
177 bool is_in_reserved(const void* p) const;
178
179 bool is_in_young(oop p); // reserved part
180 bool is_in_old(oop p); // reserved part
181
182 // Memory allocation. "gc_time_limit_was_exceeded" will
183 // be set to true if the adaptive size policy determine that
184 // an excessive amount of time is being spent doing collections
185 // and caused a NULL to be returned. If a NULL is not returned,
186 // "gc_time_limit_was_exceeded" has an undefined meaning.
187 HeapWord* mem_allocate(size_t size, bool* gc_overhead_limit_was_exceeded);
188
189 // Allocation attempt(s) during a safepoint. It should never be called
190 // to allocate a new TLAB as this allocation might be satisfied out
191 // of the old generation.
192 HeapWord* failed_mem_allocate(size_t size);
193
194 // Support for System.gc()
195 void collect(GCCause::Cause cause);
196
197 // These also should be called by the vm thread at a safepoint (e.g., from a
198 // VM operation).
199 //
200 // The first collects the young generation only, unless the scavenge fails; it
201 // will then attempt a full gc. The second collects the entire heap; if
202 // maximum_compaction is true, it will compact everything and clear all soft
203 // references.
204 inline void invoke_scavenge();
205
206 // Perform a full collection
207 virtual void do_full_collection(bool clear_all_soft_refs);
208
209 bool supports_inline_contig_alloc() const { return !UseNUMA; }
210
211 HeapWord* volatile* top_addr() const { return !UseNUMA ? young_gen()->top_addr() : (HeapWord* volatile*)-1; }
212 HeapWord** end_addr() const { return !UseNUMA ? young_gen()->end_addr() : (HeapWord**)-1; }
213
214 void ensure_parsability(bool retire_tlabs);
215 void resize_all_tlabs();
216
217 bool supports_tlab_allocation() const { return true; }
218
219 size_t tlab_capacity(Thread* thr) const;
220 size_t tlab_used(Thread* thr) const;
221 size_t unsafe_max_tlab_alloc(Thread* thr) const;
222
223 void object_iterate(ObjectClosure* cl);
224 void safe_object_iterate(ObjectClosure* cl) { object_iterate(cl); }
225
226 HeapWord* block_start(const void* addr) const;
227 size_t block_size(const HeapWord* addr) const;
228 bool block_is_obj(const HeapWord* addr) const;
229
230 jlong millis_since_last_gc();
231
232 void prepare_for_verify();
233 PSHeapSummary create_ps_heap_summary();
234 virtual void print_on(outputStream* st) const;
235 virtual void print_on_error(outputStream* st) const;
236 virtual void print_gc_threads_on(outputStream* st) const;
237 virtual void gc_threads_do(ThreadClosure* tc) const;
238 virtual void print_tracing_info() const;
239
240 void verify(VerifyOption option /* ignored */);
241
242 // Resize the young generation. The reserved space for the
243 // generation may be expanded in preparation for the resize.
244 void resize_young_gen(size_t eden_size, size_t survivor_size);
245
246 // Resize the old generation. The reserved space for the
247 // generation may be expanded in preparation for the resize.
248 void resize_old_gen(size_t desired_free_space);
249
250 // Save the tops of the spaces in all generations
251 void record_gen_tops_before_GC() PRODUCT_RETURN;
252
253 // Mangle the unused parts of all spaces in the heap
254 void gen_mangle_unused_area() PRODUCT_RETURN;
255
256 // Call these in sequential code around the processing of strong roots.
257 class ParStrongRootsScope : public MarkScope {
258 public:
259 ParStrongRootsScope();
260 ~ParStrongRootsScope();
261 };
262
263 GCMemoryManager* old_gc_manager() const { return _old_manager; }
264 GCMemoryManager* young_gc_manager() const { return _young_manager; }
265 };
266
267 // Simple class for storing info about the heap at the start of GC, to be used
268 // after GC for comparison/printing.
269 class PreGCValues {
270 public:
271 PreGCValues(ParallelScavengeHeap* heap) :
272 _heap_used(heap->used()),
273 _young_gen_used(heap->young_gen()->used_in_bytes()),
274 _old_gen_used(heap->old_gen()->used_in_bytes()),
275 _metadata_used(MetaspaceUtils::used_bytes()) { };
276
277 size_t heap_used() const { return _heap_used; }
278 size_t young_gen_used() const { return _young_gen_used; }
279 size_t old_gen_used() const { return _old_gen_used; }
280 size_t metadata_used() const { return _metadata_used; }
281
282 private:
283 size_t _heap_used;
284 size_t _young_gen_used;
285 size_t _old_gen_used;
286 size_t _metadata_used;
287 };
288
289 // Class that can be used to print information about the
290 // adaptive size policy at intervals specified by
291 // AdaptiveSizePolicyOutputInterval. Only print information
292 // if an adaptive size policy is in use.
293 class AdaptiveSizePolicyOutput : AllStatic {
294 static bool enabled() {
295 return UseParallelGC &&
296 UseAdaptiveSizePolicy &&
297 log_is_enabled(Debug, gc, ergo);
298 }
299 public:
300 static void print() {
301 if (enabled()) {
302 ParallelScavengeHeap::heap()->size_policy()->print();
303 }
304 }
305
306 static void print(AdaptiveSizePolicy* size_policy, uint count) {
307 bool do_print =
308 enabled() &&
309 (AdaptiveSizePolicyOutputInterval > 0) &&
310 (count % AdaptiveSizePolicyOutputInterval) == 0;
311
312 if (do_print) {
313 size_policy->print();
314 }
315 }
316 };
317
318 #endif // SHARE_VM_GC_PARALLEL_PARALLELSCAVENGEHEAP_HPP