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