1 /* 2 * Copyright (c) 2001, 2016, 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/ostream.hpp" 40 41 class AdjoiningGenerations; 42 class GCHeapSummary; 43 class GCTaskManager; 44 class PSAdaptiveSizePolicy; 45 class PSHeapSummary; 46 47 class ParallelScavengeHeap : public CollectedHeap { 48 friend class VMStructs; 49 private: 50 static PSYoungGen* _young_gen; 51 static PSOldGen* _old_gen; 52 53 // Sizing policy for entire heap 54 static PSAdaptiveSizePolicy* _size_policy; 55 static PSGCAdaptivePolicyCounters* _gc_policy_counters; 56 57 GenerationSizer* _collector_policy; 58 59 // Collection of generations that are adjacent in the 60 // space reserved for the heap. 61 AdjoiningGenerations* _gens; 62 unsigned int _death_march_count; 63 64 // The task manager 65 static GCTaskManager* _gc_task_manager; 66 67 void trace_heap(GCWhen::Type when, const GCTracer* tracer); 68 69 protected: 70 static inline size_t total_invocations(); 71 HeapWord* allocate_new_tlab(size_t size); 72 73 inline bool should_alloc_in_eden(size_t size) const; 74 inline void death_march_check(HeapWord* const result, size_t size); 75 HeapWord* mem_allocate_old_gen(size_t size); 76 77 public: 78 ParallelScavengeHeap(GenerationSizer* policy) : 79 CollectedHeap(), _collector_policy(policy), _death_march_count(0) { } 80 81 // For use by VM operations 82 enum CollectionType { 83 Scavenge, 84 MarkSweep 85 }; 86 87 virtual Name kind() const { 88 return CollectedHeap::ParallelScavengeHeap; 89 } 90 91 virtual const char* name() const { 92 return "Parallel"; 93 } 94 95 virtual CollectorPolicy* collector_policy() const { return _collector_policy; } 96 97 static PSYoungGen* young_gen() { return _young_gen; } 98 static PSOldGen* old_gen() { return _old_gen; } 99 100 virtual PSAdaptiveSizePolicy* size_policy() { return _size_policy; } 101 102 static PSGCAdaptivePolicyCounters* gc_policy_counters() { return _gc_policy_counters; } 103 104 static ParallelScavengeHeap* heap(); 105 106 static GCTaskManager* const gc_task_manager() { return _gc_task_manager; } 107 108 AdjoiningGenerations* gens() { return _gens; } 109 110 // Returns JNI_OK on success 111 virtual jint initialize(); 112 113 void post_initialize(); 114 void update_counters(); 115 116 // The alignment used for the various areas 117 size_t space_alignment() { return _collector_policy->space_alignment(); } 118 size_t generation_alignment() { return _collector_policy->gen_alignment(); } 119 120 // Return the (conservative) maximum heap alignment 121 static size_t conservative_max_heap_alignment() { 122 return CollectorPolicy::compute_heap_alignment(); 123 } 124 125 size_t capacity() const; 126 size_t used() const; 127 128 // Return "true" if all generations have reached the 129 // maximal committed limit that they can reach, without a garbage 130 // collection. 131 virtual bool is_maximal_no_gc() const; 132 133 // Return true if the reference points to an object that 134 // can be moved in a partial collection. For currently implemented 135 // generational collectors that means during a collection of 136 // the young gen. 137 virtual bool is_scavengable(const void* addr); 138 139 size_t max_capacity() const; 140 141 // Whether p is in the allocated part of the heap 142 bool is_in(const void* p) const; 143 144 bool is_in_reserved(const void* p) const; 145 146 bool is_in_young(oop p); // reserved part 147 bool is_in_old(oop p); // reserved part 148 149 // Memory allocation. "gc_time_limit_was_exceeded" will 150 // be set to true if the adaptive size policy determine that 151 // an excessive amount of time is being spent doing collections 152 // and caused a NULL to be returned. If a NULL is not returned, 153 // "gc_time_limit_was_exceeded" has an undefined meaning. 154 HeapWord* mem_allocate(size_t size, bool* gc_overhead_limit_was_exceeded); 155 156 // Allocation attempt(s) during a safepoint. It should never be called 157 // to allocate a new TLAB as this allocation might be satisfied out 158 // of the old generation. 159 HeapWord* failed_mem_allocate(size_t size); 160 161 // Support for System.gc() 162 void collect(GCCause::Cause cause); 163 164 // These also should be called by the vm thread at a safepoint (e.g., from a 165 // VM operation). 166 // 167 // The first collects the young generation only, unless the scavenge fails; it 168 // will then attempt a full gc. The second collects the entire heap; if 169 // maximum_compaction is true, it will compact everything and clear all soft 170 // references. 171 inline void invoke_scavenge(); 172 173 // Perform a full collection 174 virtual void do_full_collection(bool clear_all_soft_refs); 175 176 bool supports_inline_contig_alloc() const { return !UseNUMA; } 177 178 HeapWord* volatile* top_addr() const { return !UseNUMA ? young_gen()->top_addr() : (HeapWord* volatile*)-1; } 179 HeapWord** end_addr() const { return !UseNUMA ? young_gen()->end_addr() : (HeapWord**)-1; } 180 181 void ensure_parsability(bool retire_tlabs); 182 void accumulate_statistics_all_tlabs(); 183 void resize_all_tlabs(); 184 185 bool supports_tlab_allocation() const { return true; } 186 187 size_t tlab_capacity(Thread* thr) const; 188 size_t tlab_used(Thread* thr) const; 189 size_t unsafe_max_tlab_alloc(Thread* thr) const; 190 191 // Can a compiler initialize a new object without store barriers? 192 // This permission only extends from the creation of a new object 193 // via a TLAB up to the first subsequent safepoint. 194 virtual bool can_elide_tlab_store_barriers() const { 195 return true; 196 } 197 198 virtual bool card_mark_must_follow_store() const { 199 return false; 200 } 201 202 // Return true if we don't we need a store barrier for 203 // initializing stores to an object at this address. 204 virtual bool can_elide_initializing_store_barrier(oop new_obj); 205 206 void object_iterate(ObjectClosure* cl); 207 void safe_object_iterate(ObjectClosure* cl) { object_iterate(cl); } 208 209 HeapWord* block_start(const void* addr) const; 210 size_t block_size(const HeapWord* addr) const; 211 bool block_is_obj(const HeapWord* addr) const; 212 213 jlong millis_since_last_gc(); 214 215 void prepare_for_verify(); 216 PSHeapSummary create_ps_heap_summary(); 217 virtual void print_on(outputStream* st) const; 218 virtual void print_on_error(outputStream* st) const; 219 virtual void print_gc_threads_on(outputStream* st) const; 220 virtual void gc_threads_do(ThreadClosure* tc) const; 221 virtual void print_tracing_info() const; 222 223 void verify(VerifyOption option /* ignored */); 224 225 // Resize the young generation. The reserved space for the 226 // generation may be expanded in preparation for the resize. 227 void resize_young_gen(size_t eden_size, size_t survivor_size); 228 229 // Resize the old generation. The reserved space for the 230 // generation may be expanded in preparation for the resize. 231 void resize_old_gen(size_t desired_free_space); 232 233 // Save the tops of the spaces in all generations 234 void record_gen_tops_before_GC() PRODUCT_RETURN; 235 236 // Mangle the unused parts of all spaces in the heap 237 void gen_mangle_unused_area() PRODUCT_RETURN; 238 239 // Call these in sequential code around the processing of strong roots. 240 class ParStrongRootsScope : public MarkScope { 241 public: 242 ParStrongRootsScope(); 243 ~ParStrongRootsScope(); 244 }; 245 }; 246 247 // Simple class for storing info about the heap at the start of GC, to be used 248 // after GC for comparison/printing. 249 class PreGCValues { 250 public: 251 PreGCValues(ParallelScavengeHeap* heap) : 252 _heap_used(heap->used()), 253 _young_gen_used(heap->young_gen()->used_in_bytes()), 254 _old_gen_used(heap->old_gen()->used_in_bytes()), 255 _metadata_used(MetaspaceAux::used_bytes()) { }; 256 257 size_t heap_used() const { return _heap_used; } 258 size_t young_gen_used() const { return _young_gen_used; } 259 size_t old_gen_used() const { return _old_gen_used; } 260 size_t metadata_used() const { return _metadata_used; } 261 262 private: 263 size_t _heap_used; 264 size_t _young_gen_used; 265 size_t _old_gen_used; 266 size_t _metadata_used; 267 }; 268 269 #endif // SHARE_VM_GC_PARALLEL_PARALLELSCAVENGEHEAP_HPP