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