1 /* 2 * Copyright (c) 2001, 2015, 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 "utilities/ostream.hpp" 39 40 class AdjoiningGenerations; 41 class GCHeapSummary; 42 class GCTaskManager; 43 class PSAdaptiveSizePolicy; 44 class PSHeapSummary; 45 46 class ParallelScavengeHeap : public CollectedHeap { 47 friend class VMStructs; 48 private: 49 static PSYoungGen* _young_gen; 50 static PSOldGen* _old_gen; 51 52 // Sizing policy for entire heap 53 static PSAdaptiveSizePolicy* _size_policy; 54 static PSGCAdaptivePolicyCounters* _gc_policy_counters; 55 56 GenerationSizer* _collector_policy; 57 58 // Collection of generations that are adjacent in the 59 // space reserved for the heap. 60 AdjoiningGenerations* _gens; 61 unsigned int _death_march_count; 62 63 // The task manager 64 static GCTaskManager* _gc_task_manager; 65 66 void trace_heap(GCWhen::Type when, const GCTracer* tracer); 67 68 protected: 69 static inline size_t total_invocations(); 70 HeapWord* allocate_new_tlab(size_t size); 71 72 inline bool should_alloc_in_eden(size_t size) const; 73 inline void death_march_check(HeapWord* const result, size_t size); 74 HeapWord* mem_allocate_old_gen(size_t size); 75 76 public: 77 ParallelScavengeHeap(GenerationSizer* policy) : 78 CollectedHeap(), _collector_policy(policy), _death_march_count(0) { } 79 80 // For use by VM operations 81 enum CollectionType { 82 Scavenge, 83 MarkSweep 84 }; 85 86 virtual Name kind() const { 87 return CollectedHeap::ParallelScavengeHeap; 88 } 89 90 virtual CollectorPolicy* collector_policy() const { return (CollectorPolicy*) _collector_policy; } 91 92 static PSYoungGen* young_gen() { return _young_gen; } 93 static PSOldGen* old_gen() { return _old_gen; } 94 95 virtual PSAdaptiveSizePolicy* size_policy() { return _size_policy; } 96 97 static PSGCAdaptivePolicyCounters* gc_policy_counters() { return _gc_policy_counters; } 98 99 static ParallelScavengeHeap* heap(); 100 101 static GCTaskManager* const gc_task_manager() { return _gc_task_manager; } 102 103 AdjoiningGenerations* gens() { return _gens; } 104 105 // Returns JNI_OK on success 106 virtual jint initialize(); 107 108 void post_initialize(); 109 void update_counters(); 110 111 // The alignment used for the various areas 112 size_t space_alignment() { return _collector_policy->space_alignment(); } 113 size_t generation_alignment() { return _collector_policy->gen_alignment(); } 114 115 // Return the (conservative) maximum heap alignment 116 static size_t conservative_max_heap_alignment() { 117 return CollectorPolicy::compute_heap_alignment(); 118 } 119 120 size_t capacity() const; 121 size_t used() const; 122 123 // Return "true" if all generations have reached the 124 // maximal committed limit that they can reach, without a garbage 125 // collection. 126 virtual bool is_maximal_no_gc() const; 127 128 // Return true if the reference points to an object that 129 // can be moved in a partial collection. For currently implemented 130 // generational collectors that means during a collection of 131 // the young gen. 132 virtual bool is_scavengable(const void* addr); 133 134 size_t max_capacity() const; 135 136 // Whether p is in the allocated part of the heap 137 bool is_in(const void* p) const; 138 139 bool is_in_reserved(const void* p) const; 140 141 bool is_in_young(oop p); // reserved part 142 bool is_in_old(oop p); // reserved part 143 144 // Memory allocation. "gc_time_limit_was_exceeded" will 145 // be set to true if the adaptive size policy determine that 146 // an excessive amount of time is being spent doing collections 147 // and caused a NULL to be returned. If a NULL is not returned, 148 // "gc_time_limit_was_exceeded" has an undefined meaning. 149 HeapWord* mem_allocate(size_t size, bool* gc_overhead_limit_was_exceeded); 150 151 // Allocation attempt(s) during a safepoint. It should never be called 152 // to allocate a new TLAB as this allocation might be satisfied out 153 // of the old generation. 154 HeapWord* failed_mem_allocate(size_t size); 155 156 // Support for System.gc() 157 void collect(GCCause::Cause cause); 158 159 // These also should be called by the vm thread at a safepoint (e.g., from a 160 // VM operation). 161 // 162 // The first collects the young generation only, unless the scavenge fails; it 163 // will then attempt a full gc. The second collects the entire heap; if 164 // maximum_compaction is true, it will compact everything and clear all soft 165 // references. 166 inline void invoke_scavenge(); 167 168 // Perform a full collection 169 virtual void do_full_collection(bool clear_all_soft_refs); 170 171 bool supports_inline_contig_alloc() const { return !UseNUMA; } 172 173 HeapWord** top_addr() const { return !UseNUMA ? young_gen()->top_addr() : (HeapWord**)-1; } 174 HeapWord** end_addr() const { return !UseNUMA ? young_gen()->end_addr() : (HeapWord**)-1; } 175 176 void ensure_parsability(bool retire_tlabs); 177 void accumulate_statistics_all_tlabs(); 178 void resize_all_tlabs(); 179 180 bool supports_tlab_allocation() const { return true; } 181 182 size_t tlab_capacity(Thread* thr) const; 183 size_t tlab_used(Thread* thr) const; 184 size_t unsafe_max_tlab_alloc(Thread* thr) const; 185 186 // Can a compiler initialize a new object without store barriers? 187 // This permission only extends from the creation of a new object 188 // via a TLAB up to the first subsequent safepoint. 189 virtual bool can_elide_tlab_store_barriers() const { 190 return true; 191 } 192 193 virtual bool card_mark_must_follow_store() const { 194 return false; 195 } 196 197 // Return true if we don't we need a store barrier for 198 // initializing stores to an object at this address. 199 virtual bool can_elide_initializing_store_barrier(oop new_obj); 200 201 void object_iterate(ObjectClosure* cl); 202 void safe_object_iterate(ObjectClosure* cl) { object_iterate(cl); } 203 204 HeapWord* block_start(const void* addr) const; 205 size_t block_size(const HeapWord* addr) const; 206 bool block_is_obj(const HeapWord* addr) const; 207 208 jlong millis_since_last_gc(); 209 210 void prepare_for_verify(); 211 PSHeapSummary create_ps_heap_summary(); 212 virtual void print_on(outputStream* st) const; 213 virtual void print_on_error(outputStream* st) const; 214 virtual void print_gc_threads_on(outputStream* st) const; 215 virtual void gc_threads_do(ThreadClosure* tc) const; 216 virtual void print_tracing_info() const; 217 218 void verify(bool silent, VerifyOption option /* ignored */); 219 220 void print_heap_change(size_t prev_used); 221 222 // Resize the young generation. The reserved space for the 223 // generation may be expanded in preparation for the resize. 224 void resize_young_gen(size_t eden_size, size_t survivor_size); 225 226 // Resize the old generation. The reserved space for the 227 // generation may be expanded in preparation for the resize. 228 void resize_old_gen(size_t desired_free_space); 229 230 // Save the tops of the spaces in all generations 231 void record_gen_tops_before_GC() PRODUCT_RETURN; 232 233 // Mangle the unused parts of all spaces in the heap 234 void gen_mangle_unused_area() PRODUCT_RETURN; 235 236 // Call these in sequential code around the processing of strong roots. 237 class ParStrongRootsScope : public MarkScope { 238 public: 239 ParStrongRootsScope(); 240 ~ParStrongRootsScope(); 241 }; 242 }; 243 244 #endif // SHARE_VM_GC_PARALLEL_PARALLELSCAVENGEHEAP_HPP