1 /* 2 * Copyright (c) 2002, 2013, 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 "utilities/taskqueue.hpp" 33 34 // 35 // psPromotionManager is used by a single thread to manage object survival 36 // during a scavenge. The promotion manager contains thread local data only. 37 // 38 // NOTE! Be careful when allocating the stacks on cheap. If you are going 39 // to use a promotion manager in more than one thread, the stacks MUST be 40 // on cheap. This can lead to memory leaks, though, as they are not auto 41 // deallocated. 42 // 43 // FIX ME FIX ME Add a destructor, and don't rely on the user to drain/flush/deallocate! 44 // 45 46 // Move to some global location 47 #define HAS_BEEN_MOVED 0x1501d01d 48 // End move to some global location 49 50 class MutableSpace; 51 class PSOldGen; 52 class ParCompactionManager; 53 54 class PSPromotionManager : public CHeapObj<mtGC> { 55 friend class PSScavenge; 56 friend class PSRefProcTaskExecutor; 57 private: 58 static PSPromotionManager** _manager_array; 59 static OopStarTaskQueueSet* _stack_array_depth; 60 static PSOldGen* _old_gen; 61 static MutableSpace* _young_space; 62 63 #if TASKQUEUE_STATS 64 size_t _masked_pushes; 65 size_t _masked_steals; 66 size_t _arrays_chunked; 67 size_t _array_chunks_processed; 68 69 void print_taskqueue_stats(uint i) const; 70 void print_local_stats(uint i) const; 71 static void print_stats(); 72 73 void reset_stats(); 74 #endif // TASKQUEUE_STATS 75 76 PSYoungPromotionLAB _young_lab; 77 PSOldPromotionLAB _old_lab; 78 bool _young_gen_is_full; 79 bool _old_gen_is_full; 80 81 OopStarTaskQueue _claimed_stack_depth; 82 OverflowTaskQueue<oop, mtGC> _claimed_stack_breadth; 83 84 bool _totally_drain; 85 uint _target_stack_size; 86 87 uint _array_chunk_size; 88 uint _min_array_size_for_chunking; 89 90 PromotionFailedInfo _promotion_failed_info; 91 92 // Accessors 93 static PSOldGen* old_gen() { return _old_gen; } 94 static MutableSpace* young_space() { return _young_space; } 95 96 inline static PSPromotionManager* manager_array(int index); 97 template <class T> inline void claim_or_forward_internal_depth(T* p); 98 99 // On the task queues we push reference locations as well as 100 // partially-scanned arrays (in the latter case, we push an oop to 101 // the from-space image of the array and the length on the 102 // from-space image indicates how many entries on the array we still 103 // need to scan; this is basically how ParNew does partial array 104 // scanning too). To be able to distinguish between reference 105 // locations and partially-scanned array oops we simply mask the 106 // latter oops with 0x01. The next three methods do the masking, 107 // unmasking, and checking whether the oop is masked or not. Notice 108 // that the signature of the mask and unmask methods looks a bit 109 // strange, as they accept and return different types (oop and 110 // oop*). This is because of the difference in types between what 111 // the task queue holds (oop*) and oops to partially-scanned arrays 112 // (oop). We do all the necessary casting in the mask / unmask 113 // methods to avoid sprinkling the rest of the code with more casts. 114 115 // These are added to the taskqueue so PS_CHUNKED_ARRAY_OOP_MASK (or any 116 // future masks) can't conflict with COMPRESSED_OOP_MASK 117 #define PS_CHUNKED_ARRAY_OOP_MASK 0x2 118 119 bool is_oop_masked(StarTask p) { 120 // If something is marked chunked it's always treated like wide oop* 121 return (((intptr_t)(oop*)p) & PS_CHUNKED_ARRAY_OOP_MASK) == 122 PS_CHUNKED_ARRAY_OOP_MASK; 123 } 124 125 oop* mask_chunked_array_oop(oop obj) { 126 assert(!is_oop_masked((oop*) obj), "invariant"); 127 oop* ret = (oop*) ((uintptr_t)obj | PS_CHUNKED_ARRAY_OOP_MASK); 128 assert(is_oop_masked(ret), "invariant"); 129 return ret; 130 } 131 132 oop unmask_chunked_array_oop(StarTask p) { 133 assert(is_oop_masked(p), "invariant"); 134 assert(!p.is_narrow(), "chunked array oops cannot be narrow"); 135 oop *chunk = (oop*)p; // cast p to oop (uses conversion operator) 136 oop ret = oop((oop*)((uintptr_t)chunk & ~PS_CHUNKED_ARRAY_OOP_MASK)); 137 assert(!is_oop_masked((oop*) ret), "invariant"); 138 return ret; 139 } 140 141 template <class T> void process_array_chunk_work(oop obj, 142 int start, int end); 143 void process_array_chunk(oop old); 144 145 template <class T> void push_depth(T* p) { 146 claimed_stack_depth()->push(p); 147 } 148 149 protected: 150 static OopStarTaskQueueSet* stack_array_depth() { return _stack_array_depth; } 151 public: 152 // Static 153 static void initialize(); 154 155 static void pre_scavenge(); 156 static bool post_scavenge(YoungGCTracer& gc_tracer); 157 158 static PSPromotionManager* gc_thread_promotion_manager(int index); 159 static PSPromotionManager* vm_thread_promotion_manager(); 160 161 static bool steal_depth(int queue_num, int* seed, StarTask& t) { 162 return stack_array_depth()->steal(queue_num, seed, t); 163 } 164 165 PSPromotionManager(); 166 167 // Accessors 168 OopStarTaskQueue* claimed_stack_depth() { 169 return &_claimed_stack_depth; 170 } 171 172 bool young_gen_is_full() { return _young_gen_is_full; } 173 174 bool old_gen_is_full() { return _old_gen_is_full; } 175 void set_old_gen_is_full(bool state) { _old_gen_is_full = state; } 176 177 // Promotion methods 178 template<bool promote_immediately> oop copy_to_survivor_space(oop o); 179 oop oop_promotion_failed(oop obj, markOop obj_mark); 180 181 void reset(); 182 183 void flush_labs(); 184 void drain_stacks(bool totally_drain) { 185 drain_stacks_depth(totally_drain); 186 } 187 public: 188 void drain_stacks_cond_depth() { 189 if (claimed_stack_depth()->size() > _target_stack_size) { 190 drain_stacks_depth(false); 191 } 192 } 193 void drain_stacks_depth(bool totally_drain); 194 195 bool stacks_empty() { 196 return claimed_stack_depth()->is_empty(); 197 } 198 199 inline void process_popped_location_depth(StarTask p); 200 201 template <class T> inline void claim_or_forward_depth(T* p); 202 203 TASKQUEUE_STATS_ONLY(inline void record_steal(StarTask& p);) 204 }; 205 206 #endif // SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_PSPROMOTIONMANAGER_HPP