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