1 /* 2 * Copyright (c) 2002, 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. 22 * 23 */ 24 25 #ifndef SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_PSPROMOTIONMANAGER_HPP 26 #define SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_PSPROMOTIONMANAGER_HPP 27 28 #include "gc_implementation/parallelScavenge/psPromotionLAB.hpp" 29 #include "gc_implementation/shared/gcTrace.hpp" 30 #include "gc_implementation/shared/copyFailedInfo.hpp" 31 #include "memory/allocation.hpp" 32 #include "memory/padded.hpp" 33 #include "utilities/globalDefinitions.hpp" 34 #include "utilities/taskqueue.hpp" 35 36 // 37 // psPromotionManager is used by a single thread to manage object survival 38 // during a scavenge. The promotion manager contains thread local data only. 39 // 40 // NOTE! Be careful when allocating the stacks on cheap. If you are going 41 // to use a promotion manager in more than one thread, the stacks MUST be 42 // on cheap. This can lead to memory leaks, though, as they are not auto 43 // deallocated. 44 // 45 // FIX ME FIX ME Add a destructor, and don't rely on the user to drain/flush/deallocate! 46 // 47 48 // Move to some global location 49 #define HAS_BEEN_MOVED 0x1501d01d 50 // End move to some global location 51 52 class MutableSpace; 53 class PSOldGen; 54 class ParCompactionManager; 55 56 class PSPromotionManager VALUE_OBJ_CLASS_SPEC { 57 friend class PSScavenge; 58 friend class PSRefProcTaskExecutor; 59 private: 60 static PaddedEnd<PSPromotionManager>* _manager_array; 61 static OopStarTaskQueueSet* _stack_array_depth; 62 static PSOldGen* _old_gen; 63 static MutableSpace* _young_space; 64 65 #if TASKQUEUE_STATS 66 size_t _masked_pushes; 67 size_t _masked_steals; 68 size_t _arrays_chunked; 69 size_t _array_chunks_processed; 70 71 void print_taskqueue_stats(uint i) const; 72 void print_local_stats(uint i) const; 73 static void print_stats(); 74 75 void reset_stats(); 76 #endif // TASKQUEUE_STATS 77 78 PSYoungPromotionLAB _young_lab; 79 PSOldPromotionLAB _old_lab; 80 bool _young_gen_is_full; 81 bool _old_gen_is_full; 82 83 OopStarTaskQueue _claimed_stack_depth; 84 OverflowTaskQueue<oop, mtGC> _claimed_stack_breadth; 85 86 bool _totally_drain; 87 uint _target_stack_size; 88 89 uint _array_chunk_size; 90 uint _min_array_size_for_chunking; 91 92 PromotionFailedInfo _promotion_failed_info; 93 94 // Accessors 95 static PSOldGen* old_gen() { return _old_gen; } 96 static MutableSpace* young_space() { return _young_space; } 97 98 inline static PSPromotionManager* manager_array(int index); 99 template <class T> inline void claim_or_forward_internal_depth(T* p); 100 101 // On the task queues we push reference locations as well as 102 // partially-scanned arrays (in the latter case, we push an oop to 103 // the from-space image of the array and the length on the 104 // from-space image indicates how many entries on the array we still 105 // need to scan; this is basically how ParNew does partial array 106 // scanning too). To be able to distinguish between reference 107 // locations and partially-scanned array oops we simply mask the 108 // latter oops with 0x01. The next three methods do the masking, 109 // unmasking, and checking whether the oop is masked or not. Notice 110 // that the signature of the mask and unmask methods looks a bit 111 // strange, as they accept and return different types (oop and 112 // oop*). This is because of the difference in types between what 113 // the task queue holds (oop*) and oops to partially-scanned arrays 114 // (oop). We do all the necessary casting in the mask / unmask 115 // methods to avoid sprinkling the rest of the code with more casts. 116 117 // These are added to the taskqueue so PS_CHUNKED_ARRAY_OOP_MASK (or any 118 // future masks) can't conflict with COMPRESSED_OOP_MASK 119 #define PS_CHUNKED_ARRAY_OOP_MASK 0x2 120 121 bool is_oop_masked(StarTask p) { 122 // If something is marked chunked it's always treated like wide oop* 123 return (((intptr_t)(oop*)p) & PS_CHUNKED_ARRAY_OOP_MASK) == 124 PS_CHUNKED_ARRAY_OOP_MASK; 125 } 126 127 oop* mask_chunked_array_oop(oop obj) { 128 assert(!is_oop_masked((oop*) obj), "invariant"); 129 oop* ret = (oop*) (cast_from_oop<uintptr_t>(obj) | PS_CHUNKED_ARRAY_OOP_MASK); 130 assert(is_oop_masked(ret), "invariant"); 131 return ret; 132 } 133 134 oop unmask_chunked_array_oop(StarTask p) { 135 assert(is_oop_masked(p), "invariant"); 136 assert(!p.is_narrow(), "chunked array oops cannot be narrow"); 137 oop *chunk = (oop*)p; // cast p to oop (uses conversion operator) 138 oop ret = oop((oop*)((uintptr_t)chunk & ~PS_CHUNKED_ARRAY_OOP_MASK)); 139 assert(!is_oop_masked((oop*) ret), "invariant"); 140 return ret; 141 } 142 143 template <class T> void process_array_chunk_work(oop obj, 144 int start, int end); 145 void process_array_chunk(oop old); 146 147 template <class T> void push_depth(T* p) { 148 claimed_stack_depth()->push(p); 149 } 150 151 inline void promotion_trace_event(oop new_obj, oop old_obj, size_t obj_size, 152 uint age, bool tenured, 153 const PSPromotionLAB* lab); 154 155 protected: 156 static OopStarTaskQueueSet* stack_array_depth() { return _stack_array_depth; } 157 public: 158 // Static 159 static void initialize(); 160 161 static void pre_scavenge(); 162 static bool post_scavenge(YoungGCTracer& gc_tracer); 163 164 static PSPromotionManager* gc_thread_promotion_manager(int index); 165 static PSPromotionManager* vm_thread_promotion_manager(); 166 167 static bool steal_depth(int queue_num, int* seed, StarTask& t) { 168 return stack_array_depth()->steal(queue_num, seed, t); 169 } 170 171 PSPromotionManager(); 172 173 // Accessors 174 OopStarTaskQueue* claimed_stack_depth() { 175 return &_claimed_stack_depth; 176 } 177 178 bool young_gen_is_full() { return _young_gen_is_full; } 179 180 bool old_gen_is_full() { return _old_gen_is_full; } 181 void set_old_gen_is_full(bool state) { _old_gen_is_full = state; } 182 183 // Promotion methods 184 template<bool promote_immediately> oop copy_to_survivor_space(oop o); 185 oop oop_promotion_failed(oop obj, markOop obj_mark); 186 187 void reset(); 188 189 void flush_labs(); 190 void drain_stacks(bool totally_drain) { 191 drain_stacks_depth(totally_drain); 192 } 193 public: 194 void drain_stacks_cond_depth() { 195 if (claimed_stack_depth()->size() > _target_stack_size) { 196 drain_stacks_depth(false); 197 } 198 } 199 void drain_stacks_depth(bool totally_drain); 200 201 bool stacks_empty() { 202 return claimed_stack_depth()->is_empty(); 203 } 204 205 inline void process_popped_location_depth(StarTask p); 206 207 template <class T> inline void claim_or_forward_depth(T* p); 208 209 TASKQUEUE_STATS_ONLY(inline void record_steal(StarTask& p);) 210 }; 211 212 #endif // SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_PSPROMOTIONMANAGER_HPP