1 /* 2 * Copyright (c) 2002, 2012, 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_INLINE_HPP 26 #define SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_PSPROMOTIONMANAGER_INLINE_HPP 27 28 #include "gc_implementation/parallelScavenge/psPromotionManager.hpp" 29 #include "gc_implementation/parallelScavenge/psScavenge.hpp" 30 31 inline PSPromotionManager* PSPromotionManager::manager_array(int index) { 32 assert(_manager_array != NULL, "access of NULL manager_array"); 33 assert(index >= 0 && index <= (int)ParallelGCThreads, "out of range manager_array access"); 34 return _manager_array[index]; 35 } 36 37 template <class T> 38 inline void PSPromotionManager::claim_or_forward_internal_depth(T* p) { 39 if (p != NULL) { // XXX: error if p != NULL here 40 oop o = oopDesc::load_decode_heap_oop_not_null(p); 41 if (o->is_forwarded()) { 42 o = o->forwardee(); 43 // Card mark 44 if (PSScavenge::is_obj_in_young((HeapWord*) o)) { 45 PSScavenge::card_table()->inline_write_ref_field_gc(p, o); 46 } 47 oopDesc::encode_store_heap_oop_not_null(p, o); 48 } else { 49 push_depth(p); 50 } 51 } 52 } 53 54 template <class T> 55 inline void PSPromotionManager::claim_or_forward_depth(T* p) { 56 assert(PSScavenge::should_scavenge(p, true), "revisiting object?"); 57 assert(Universe::heap()->kind() == CollectedHeap::ParallelScavengeHeap, 58 "Sanity"); 59 assert(Universe::heap()->is_in(p), "pointer outside heap"); 60 61 claim_or_forward_internal_depth(p); 62 } 63 64 // 65 // This method is pretty bulky. It would be nice to split it up 66 // into smaller submethods, but we need to be careful not to hurt 67 // performance. 68 // 69 template<bool promote_immediately> 70 oop PSPromotionManager::copy_to_survivor_space(oop o) { 71 assert(PSScavenge::should_scavenge(&o), "Sanity"); 72 73 oop new_obj = NULL; 74 75 // NOTE! We must be very careful with any methods that access the mark 76 // in o. There may be multiple threads racing on it, and it may be forwarded 77 // at any time. Do not use oop methods for accessing the mark! 78 markOop test_mark = o->mark(); 79 80 // The same test as "o->is_forwarded()" 81 if (!test_mark->is_marked()) { 82 bool new_obj_is_tenured = false; 83 size_t new_obj_size = o->size(); 84 85 if (!promote_immediately) { 86 // Find the objects age, MT safe. 87 int age = (test_mark->has_displaced_mark_helper() /* o->has_displaced_mark() */) ? 88 test_mark->displaced_mark_helper()->age() : test_mark->age(); 89 90 // Try allocating obj in to-space (unless too old) 91 if (age < PSScavenge::tenuring_threshold()) { 92 new_obj = (oop) _young_lab.allocate(new_obj_size); 93 if (new_obj == NULL && !_young_gen_is_full) { 94 // Do we allocate directly, or flush and refill? 95 if (new_obj_size > (YoungPLABSize / 2)) { 96 // Allocate this object directly 97 new_obj = (oop)young_space()->cas_allocate(new_obj_size); 98 } else { 99 // Flush and fill 100 _young_lab.flush(); 101 102 HeapWord* lab_base = young_space()->cas_allocate(YoungPLABSize); 103 if (lab_base != NULL) { 104 _young_lab.initialize(MemRegion(lab_base, YoungPLABSize)); 105 // Try the young lab allocation again. 106 new_obj = (oop) _young_lab.allocate(new_obj_size); 107 } else { 108 _young_gen_is_full = true; 109 } 110 } 111 } 112 } 113 } 114 115 // Otherwise try allocating obj tenured 116 if (new_obj == NULL) { 117 #ifndef PRODUCT 118 if (Universe::heap()->promotion_should_fail()) { 119 return oop_promotion_failed(o, test_mark); 120 } 121 #endif // #ifndef PRODUCT 122 123 new_obj = (oop) _old_lab.allocate(new_obj_size); 124 new_obj_is_tenured = true; 125 126 if (new_obj == NULL) { 127 if (!_old_gen_is_full) { 128 // Do we allocate directly, or flush and refill? 129 if (new_obj_size > (OldPLABSize / 2)) { 130 // Allocate this object directly 131 new_obj = (oop)old_gen()->cas_allocate(new_obj_size); 132 } else { 133 // Flush and fill 134 _old_lab.flush(); 135 136 HeapWord* lab_base = old_gen()->cas_allocate(OldPLABSize); 137 if(lab_base != NULL) { 138 _old_lab.initialize(MemRegion(lab_base, OldPLABSize)); 139 // Try the old lab allocation again. 140 new_obj = (oop) _old_lab.allocate(new_obj_size); 141 } 142 } 143 } 144 145 // This is the promotion failed test, and code handling. 146 // The code belongs here for two reasons. It is slightly 147 // different thatn the code below, and cannot share the 148 // CAS testing code. Keeping the code here also minimizes 149 // the impact on the common case fast path code. 150 151 if (new_obj == NULL) { 152 _old_gen_is_full = true; 153 return oop_promotion_failed(o, test_mark); 154 } 155 } 156 } 157 158 assert(new_obj != NULL, "allocation should have succeeded"); 159 160 // Copy obj 161 Copy::aligned_disjoint_words((HeapWord*)o, (HeapWord*)new_obj, new_obj_size); 162 163 // Now we have to CAS in the header. 164 if (o->cas_forward_to(new_obj, test_mark)) { 165 // We won any races, we "own" this object. 166 assert(new_obj == o->forwardee(), "Sanity"); 167 168 // Increment age if obj still in new generation. Now that 169 // we're dealing with a markOop that cannot change, it is 170 // okay to use the non mt safe oop methods. 171 if (!new_obj_is_tenured) { 172 new_obj->incr_age(); 173 assert(young_space()->contains(new_obj), "Attempt to push non-promoted obj"); 174 } 175 176 // Do the size comparison first with new_obj_size, which we 177 // already have. Hopefully, only a few objects are larger than 178 // _min_array_size_for_chunking, and most of them will be arrays. 179 // So, the is->objArray() test would be very infrequent. 180 if (new_obj_size > _min_array_size_for_chunking && 181 new_obj->is_objArray() && 182 PSChunkLargeArrays) { 183 // we'll chunk it 184 oop* const masked_o = mask_chunked_array_oop(o); 185 push_depth(masked_o); 186 TASKQUEUE_STATS_ONLY(++_arrays_chunked; ++_masked_pushes); 187 } else { 188 // we'll just push its contents 189 new_obj->push_contents(this); 190 } 191 } else { 192 // We lost, someone else "owns" this object 193 guarantee(o->is_forwarded(), "Object must be forwarded if the cas failed."); 194 195 // Try to deallocate the space. If it was directly allocated we cannot 196 // deallocate it, so we have to test. If the deallocation fails, 197 // overwrite with a filler object. 198 if (new_obj_is_tenured) { 199 if (!_old_lab.unallocate_object((HeapWord*) new_obj, new_obj_size)) { 200 CollectedHeap::fill_with_object((HeapWord*) new_obj, new_obj_size); 201 } 202 } else if (!_young_lab.unallocate_object((HeapWord*) new_obj, new_obj_size)) { 203 CollectedHeap::fill_with_object((HeapWord*) new_obj, new_obj_size); 204 } 205 206 // don't update this before the unallocation! 207 new_obj = o->forwardee(); 208 } 209 } else { 210 assert(o->is_forwarded(), "Sanity"); 211 new_obj = o->forwardee(); 212 } 213 214 #ifdef DEBUG 215 // This code must come after the CAS test, or it will print incorrect 216 // information. 217 if (TraceScavenge) { 218 gclog_or_tty->print_cr("{%s %s " PTR_FORMAT " -> " PTR_FORMAT " (" SIZE_FORMAT ")}", 219 PSScavenge::should_scavenge(&new_obj) ? "copying" : "tenuring", 220 new_obj->blueprint()->internal_name(), o, new_obj, new_obj->size()); 221 } 222 #endif 223 224 return new_obj; 225 } 226 227 228 inline void PSPromotionManager::process_popped_location_depth(StarTask p) { 229 if (is_oop_masked(p)) { 230 assert(PSChunkLargeArrays, "invariant"); 231 oop const old = unmask_chunked_array_oop(p); 232 process_array_chunk(old); 233 } else { 234 if (p.is_narrow()) { 235 assert(UseCompressedOops, "Error"); 236 PSScavenge::copy_and_push_safe_barrier<narrowOop, /*promote_immediately=*/false>(this, p); 237 } else { 238 PSScavenge::copy_and_push_safe_barrier<oop, /*promote_immediately=*/false>(this, p); 239 } 240 } 241 } 242 243 #if TASKQUEUE_STATS 244 void PSPromotionManager::record_steal(StarTask& p) { 245 if (is_oop_masked(p)) { 246 ++_masked_steals; 247 } 248 } 249 #endif // TASKQUEUE_STATS 250 251 #endif // SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_PSPROMOTIONMANAGER_INLINE_HPP