1 /*
2 * Copyright (c) 2001, 2019, 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_GC_PARALLEL_PARALLELSCAVENGEHEAP_HPP
26 #define SHARE_GC_PARALLEL_PARALLELSCAVENGEHEAP_HPP
27
28 #include "gc/parallel/objectStartArray.hpp"
29 #include "gc/parallel/psGCAdaptivePolicyCounters.hpp"
30 #include "gc/parallel/psOldGen.hpp"
31 #include "gc/parallel/psYoungGen.hpp"
32 #include "gc/shared/cardTableBarrierSet.hpp"
33 #include "gc/shared/collectedHeap.hpp"
34 #include "gc/shared/gcPolicyCounters.hpp"
35 #include "gc/shared/gcWhen.hpp"
36 #include "gc/shared/referenceProcessor.hpp"
37 #include "gc/shared/softRefPolicy.hpp"
38 #include "gc/shared/strongRootsScope.hpp"
39 #include "gc/shared/workgroup.hpp"
40 #include "logging/log.hpp"
41 #include "memory/metaspace.hpp"
42 #include "utilities/growableArray.hpp"
43 #include "utilities/ostream.hpp"
44
45 class AdjoiningGenerations;
46 class GCHeapSummary;
47 class GCTaskManager;
48 class MemoryManager;
49 class MemoryPool;
50 class PSAdaptiveSizePolicy;
51 class PSCardTable;
52 class PSHeapSummary;
53
54 class ParallelScavengeHeap : public CollectedHeap {
55 friend class VMStructs;
56 private:
57 static PSYoungGen* _young_gen;
58 static PSOldGen* _old_gen;
59
60 // Sizing policy for entire heap
61 static PSAdaptiveSizePolicy* _size_policy;
62 static PSGCAdaptivePolicyCounters* _gc_policy_counters;
63
64 SoftRefPolicy _soft_ref_policy;
65
66 // Collection of generations that are adjacent in the
67 // space reserved for the heap.
68 AdjoiningGenerations* _gens;
69 unsigned int _death_march_count;
70
71 // The task manager
72 static GCTaskManager* _gc_task_manager;
73
74 GCMemoryManager* _young_manager;
75 GCMemoryManager* _old_manager;
76
77 MemoryPool* _eden_pool;
78 MemoryPool* _survivor_pool;
79 MemoryPool* _old_pool;
80
81 WorkGang _workers;
82
83 virtual void initialize_serviceability();
84
85 void trace_heap(GCWhen::Type when, const GCTracer* tracer);
86
87 protected:
88 static inline size_t total_invocations();
89 HeapWord* allocate_new_tlab(size_t min_size, size_t requested_size, size_t* actual_size);
90
91 inline bool should_alloc_in_eden(size_t size) const;
92 inline void death_march_check(HeapWord* const result, size_t size);
93 HeapWord* mem_allocate_old_gen(size_t size);
94
95 public:
96 ParallelScavengeHeap() :
97 CollectedHeap(),
98 _gens(NULL),
99 _death_march_count(0),
100 _young_manager(NULL),
101 _old_manager(NULL),
102 _eden_pool(NULL),
103 _survivor_pool(NULL),
104 _old_pool(NULL),
105 _workers("GC Thread", ParallelGCThreads,
106 true /* are_GC_task_threads */,
107 false /* are_ConcurrentGC_threads */) { }
108
109 // For use by VM operations
110 enum CollectionType {
111 Scavenge,
112 MarkSweep
113 };
114
115 virtual Name kind() const {
116 return CollectedHeap::Parallel;
117 }
118
119 virtual const char* name() const {
120 return "Parallel";
121 }
122
123 virtual SoftRefPolicy* soft_ref_policy() { return &_soft_ref_policy; }
124
125 virtual GrowableArray<GCMemoryManager*> memory_managers();
126 virtual GrowableArray<MemoryPool*> memory_pools();
127
128 static PSYoungGen* young_gen() { return _young_gen; }
129 static PSOldGen* old_gen() { return _old_gen; }
130
131 virtual PSAdaptiveSizePolicy* size_policy() { return _size_policy; }
132
133 static PSGCAdaptivePolicyCounters* gc_policy_counters() { return _gc_policy_counters; }
134
135 static ParallelScavengeHeap* heap();
136
137 static GCTaskManager* const gc_task_manager() { return _gc_task_manager; }
138
139 CardTableBarrierSet* barrier_set();
140 PSCardTable* card_table();
141
142 AdjoiningGenerations* gens() { return _gens; }
143
144 // Returns JNI_OK on success
145 virtual jint initialize();
146
147 void post_initialize();
148 void update_counters();
149
150 size_t capacity() const;
151 size_t used() const;
152
153 // Return "true" if all generations have reached the
154 // maximal committed limit that they can reach, without a garbage
155 // collection.
156 virtual bool is_maximal_no_gc() const;
157
158 virtual void register_nmethod(nmethod* nm);
159 virtual void unregister_nmethod(nmethod* nm);
160 virtual void verify_nmethod(nmethod* nm);
161 virtual void flush_nmethod(nmethod* nm);
162
163 void prune_scavengable_nmethods();
164
165 size_t max_capacity() const;
166
167 // Whether p is in the allocated part of the heap
168 bool is_in(const void* p) const;
169
170 bool is_in_reserved(const void* p) const;
171
172 bool is_in_young(oop p); // reserved part
173 bool is_in_old(oop p); // reserved part
174
175 // Memory allocation. "gc_time_limit_was_exceeded" will
176 // be set to true if the adaptive size policy determine that
177 // an excessive amount of time is being spent doing collections
178 // and caused a NULL to be returned. If a NULL is not returned,
179 // "gc_time_limit_was_exceeded" has an undefined meaning.
180 HeapWord* mem_allocate(size_t size, bool* gc_overhead_limit_was_exceeded);
181
182 // Allocation attempt(s) during a safepoint. It should never be called
183 // to allocate a new TLAB as this allocation might be satisfied out
184 // of the old generation.
185 HeapWord* failed_mem_allocate(size_t size);
186
187 // Support for System.gc()
188 void collect(GCCause::Cause cause);
189
190 // These also should be called by the vm thread at a safepoint (e.g., from a
191 // VM operation).
192 //
193 // The first collects the young generation only, unless the scavenge fails; it
194 // will then attempt a full gc. The second collects the entire heap; if
195 // maximum_compaction is true, it will compact everything and clear all soft
196 // references.
197 inline void invoke_scavenge();
198
199 // Perform a full collection
200 virtual void do_full_collection(bool clear_all_soft_refs);
201
202 bool supports_inline_contig_alloc() const { return !UseNUMA; }
203
204 HeapWord* volatile* top_addr() const { return !UseNUMA ? young_gen()->top_addr() : (HeapWord* volatile*)-1; }
205 HeapWord** end_addr() const { return !UseNUMA ? young_gen()->end_addr() : (HeapWord**)-1; }
206
207 void ensure_parsability(bool retire_tlabs);
208 void resize_all_tlabs();
209
210 bool supports_tlab_allocation() const { return true; }
211
212 size_t tlab_capacity(Thread* thr) const;
213 size_t tlab_used(Thread* thr) const;
214 size_t unsafe_max_tlab_alloc(Thread* thr) const;
215
216 void object_iterate(ObjectClosure* cl);
217 void safe_object_iterate(ObjectClosure* cl) { object_iterate(cl); }
218
219 HeapWord* block_start(const void* addr) const;
220 bool block_is_obj(const HeapWord* addr) const;
221
222 jlong millis_since_last_gc();
223
224 void prepare_for_verify();
225 PSHeapSummary create_ps_heap_summary();
226 virtual void print_on(outputStream* st) const;
227 virtual void print_on_error(outputStream* st) const;
228 virtual void print_gc_threads_on(outputStream* st) const;
229 virtual void gc_threads_do(ThreadClosure* tc) const;
230 virtual void print_tracing_info() const;
231
232 void verify(VerifyOption option /* ignored */);
233
234 // Resize the young generation. The reserved space for the
235 // generation may be expanded in preparation for the resize.
236 void resize_young_gen(size_t eden_size, size_t survivor_size);
237
238 // Resize the old generation. The reserved space for the
239 // generation may be expanded in preparation for the resize.
240 void resize_old_gen(size_t desired_free_space);
241
242 // Save the tops of the spaces in all generations
243 void record_gen_tops_before_GC() PRODUCT_RETURN;
244
245 // Mangle the unused parts of all spaces in the heap
246 void gen_mangle_unused_area() PRODUCT_RETURN;
247
248 // Call these in sequential code around the processing of strong roots.
249 class ParStrongRootsScope : public MarkScope {
250 public:
251 ParStrongRootsScope();
252 ~ParStrongRootsScope();
253 };
254
255 GCMemoryManager* old_gc_manager() const { return _old_manager; }
256 GCMemoryManager* young_gc_manager() const { return _young_manager; }
257
258 WorkGang& workers() {
259 return _workers;
260 }
261 };
262
263 // Simple class for storing info about the heap at the start of GC, to be used
264 // after GC for comparison/printing.
265 class PreGCValues {
266 public:
267 PreGCValues(ParallelScavengeHeap* heap) :
268 _heap_used(heap->used()),
269 _young_gen_used(heap->young_gen()->used_in_bytes()),
270 _old_gen_used(heap->old_gen()->used_in_bytes()),
271 _metadata_used(MetaspaceUtils::used_bytes()) { };
272
273 size_t heap_used() const { return _heap_used; }
274 size_t young_gen_used() const { return _young_gen_used; }
275 size_t old_gen_used() const { return _old_gen_used; }
276 size_t metadata_used() const { return _metadata_used; }
277
278 private:
279 size_t _heap_used;
280 size_t _young_gen_used;
281 size_t _old_gen_used;
282 size_t _metadata_used;
283 };
284
285 // Class that can be used to print information about the
286 // adaptive size policy at intervals specified by
287 // AdaptiveSizePolicyOutputInterval. Only print information
288 // if an adaptive size policy is in use.
289 class AdaptiveSizePolicyOutput : AllStatic {
290 static bool enabled() {
291 return UseParallelGC &&
292 UseAdaptiveSizePolicy &&
293 log_is_enabled(Debug, gc, ergo);
294 }
295 public:
296 static void print() {
297 if (enabled()) {
298 ParallelScavengeHeap::heap()->size_policy()->print();
299 }
300 }
301
302 static void print(AdaptiveSizePolicy* size_policy, uint count) {
303 bool do_print =
304 enabled() &&
305 (AdaptiveSizePolicyOutputInterval > 0) &&
306 (count % AdaptiveSizePolicyOutputInterval) == 0;
307
308 if (do_print) {
309 size_policy->print();
310 }
311 }
312 };
313
314 #endif // SHARE_GC_PARALLEL_PARALLELSCAVENGEHEAP_HPP