1 /*
2 * Copyright (c) 2001, 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.
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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/growableArray.hpp"
40 #include "utilities/ostream.hpp"
41
42 class AdjoiningGenerations;
43 class GCHeapSummary;
44 class GCTaskManager;
45 class MemoryManager;
46 class MemoryPool;
47 class PSAdaptiveSizePolicy;
48 class PSHeapSummary;
49
50 class ParallelScavengeHeap : public CollectedHeap {
51 friend class VMStructs;
52 private:
53 static PSYoungGen* _young_gen;
54 static PSOldGen* _old_gen;
55
56 // Sizing policy for entire heap
57 static PSAdaptiveSizePolicy* _size_policy;
58 static PSGCAdaptivePolicyCounters* _gc_policy_counters;
59
60 GenerationSizer* _collector_policy;
61
62 // Collection of generations that are adjacent in the
63 // space reserved for the heap.
64 AdjoiningGenerations* _gens;
65 unsigned int _death_march_count;
66
67 // The task manager
68 static GCTaskManager* _gc_task_manager;
69
70 GCMemoryManager* _young_manager;
71 GCMemoryManager* _old_manager;
72
73 MemoryPool* _eden_pool;
74 MemoryPool* _survivor_pool;
75 MemoryPool* _old_pool;
76
77 virtual void initialize_serviceability();
78
79 void trace_heap(GCWhen::Type when, const GCTracer* tracer);
80
81 protected:
82 static inline size_t total_invocations();
83 HeapWord* allocate_new_tlab(size_t size);
84
85 inline bool should_alloc_in_eden(size_t size) const;
86 inline void death_march_check(HeapWord* const result, size_t size);
87 HeapWord* mem_allocate_old_gen(size_t size);
88
89 public:
90 ParallelScavengeHeap(GenerationSizer* policy) :
91 CollectedHeap(), _collector_policy(policy), _death_march_count(0) { }
92
93 // For use by VM operations
94 enum CollectionType {
95 Scavenge,
96 MarkSweep
97 };
98
99 virtual Name kind() const {
100 return CollectedHeap::ParallelScavengeHeap;
101 }
102
103 virtual const char* name() const {
104 return "Parallel";
105 }
106
107 virtual CollectorPolicy* collector_policy() const { return _collector_policy; }
108
109 virtual GrowableArray<GCMemoryManager*> memory_managers();
110 virtual GrowableArray<MemoryPool*> memory_pools();
111
112 static PSYoungGen* young_gen() { return _young_gen; }
113 static PSOldGen* old_gen() { return _old_gen; }
114
115 virtual PSAdaptiveSizePolicy* size_policy() { return _size_policy; }
116
117 static PSGCAdaptivePolicyCounters* gc_policy_counters() { return _gc_policy_counters; }
118
119 static ParallelScavengeHeap* heap();
120
121 static GCTaskManager* const gc_task_manager() { return _gc_task_manager; }
122
123 AdjoiningGenerations* gens() { return _gens; }
124
125 // Returns JNI_OK on success
126 virtual jint initialize();
127
128 void post_initialize();
129 void update_counters();
130
131 // The alignment used for the various areas
132 size_t space_alignment() { return _collector_policy->space_alignment(); }
133 size_t generation_alignment() { return _collector_policy->gen_alignment(); }
134
135 // Return the (conservative) maximum heap alignment
136 static size_t conservative_max_heap_alignment() {
137 return CollectorPolicy::compute_heap_alignment();
138 }
139
140 size_t capacity() const;
141 size_t used() const;
142
143 // Return "true" if all generations have reached the
144 // maximal committed limit that they can reach, without a garbage
145 // collection.
146 virtual bool is_maximal_no_gc() const;
147
148 // Return true if the reference points to an object that
149 // can be moved in a partial collection. For currently implemented
150 // generational collectors that means during a collection of
151 // the young gen.
152 virtual bool is_scavengable(oop obj);
153 virtual void register_nmethod(nmethod* nm);
154 virtual void verify_nmethod(nmethod* nmethod);
155
156 size_t max_capacity() const;
157
158 // Whether p is in the allocated part of the heap
159 bool is_in(const void* p) const;
160
161 bool is_in_reserved(const void* p) const;
162
163 bool is_in_young(oop p); // reserved part
164 bool is_in_old(oop p); // reserved part
165
166 // Memory allocation. "gc_time_limit_was_exceeded" will
167 // be set to true if the adaptive size policy determine that
168 // an excessive amount of time is being spent doing collections
169 // and caused a NULL to be returned. If a NULL is not returned,
170 // "gc_time_limit_was_exceeded" has an undefined meaning.
171 HeapWord* mem_allocate(size_t size, bool* gc_overhead_limit_was_exceeded);
172
173 // Allocation attempt(s) during a safepoint. It should never be called
174 // to allocate a new TLAB as this allocation might be satisfied out
175 // of the old generation.
176 HeapWord* failed_mem_allocate(size_t size);
177
178 // Support for System.gc()
179 void collect(GCCause::Cause cause);
180
181 // These also should be called by the vm thread at a safepoint (e.g., from a
182 // VM operation).
183 //
184 // The first collects the young generation only, unless the scavenge fails; it
185 // will then attempt a full gc. The second collects the entire heap; if
186 // maximum_compaction is true, it will compact everything and clear all soft
187 // references.
188 inline void invoke_scavenge();
189
190 // Perform a full collection
191 virtual void do_full_collection(bool clear_all_soft_refs);
192
193 bool supports_inline_contig_alloc() const { return !UseNUMA; }
194
195 HeapWord* volatile* top_addr() const { return !UseNUMA ? young_gen()->top_addr() : (HeapWord* volatile*)-1; }
196 HeapWord** end_addr() const { return !UseNUMA ? young_gen()->end_addr() : (HeapWord**)-1; }
197
198 void ensure_parsability(bool retire_tlabs);
199 void accumulate_statistics_all_tlabs();
200 void resize_all_tlabs();
201
202 bool supports_tlab_allocation() const { return true; }
203
204 size_t tlab_capacity(Thread* thr) const;
205 size_t tlab_used(Thread* thr) const;
206 size_t unsafe_max_tlab_alloc(Thread* thr) const;
207
208 // Can a compiler initialize a new object without store barriers?
209 // This permission only extends from the creation of a new object
210 // via a TLAB up to the first subsequent safepoint.
211 virtual bool can_elide_tlab_store_barriers() const {
212 return true;
213 }
214
215 virtual bool card_mark_must_follow_store() const {
216 return false;
217 }
218
219 // Return true if we don't we need a store barrier for
220 // initializing stores to an object at this address.
221 virtual bool can_elide_initializing_store_barrier(oop new_obj);
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(MetaspaceAux::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