1 /* 2 * Copyright (c) 2002, 2014, 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/psOldGen.hpp" 29 #include "gc_implementation/parallelScavenge/psPromotionManager.hpp" 30 #include "gc_implementation/parallelScavenge/psPromotionLAB.inline.hpp" 31 #include "gc_implementation/parallelScavenge/psScavenge.hpp" 32 #include "oops/oop.psgc.inline.hpp" 33 34 inline PSPromotionManager* PSPromotionManager::manager_array(int index) { 35 assert(_manager_array != NULL, "access of NULL manager_array"); 36 assert(index >= 0 && index <= (int)ParallelGCThreads, "out of range manager_array access"); 37 return &_manager_array[index]; 38 } 39 40 template <class T> 41 inline void PSPromotionManager::claim_or_forward_internal_depth(T* p) { 42 if (p != NULL) { // XXX: error if p != NULL here 43 oop o = oopDesc::load_decode_heap_oop_not_null(p); 44 if (o->is_forwarded()) { 45 o = o->forwardee(); 46 // Card mark 47 if (PSScavenge::is_obj_in_young(o)) { 48 PSScavenge::card_table()->inline_write_ref_field_gc(p, o); 49 } 50 oopDesc::encode_store_heap_oop_not_null(p, o); 51 } else { 52 push_depth(p); 53 } 54 } 55 } 56 57 template <class T> 58 inline void PSPromotionManager::claim_or_forward_depth(T* p) { 59 assert(PSScavenge::should_scavenge(p, true), "revisiting object?"); 60 assert(Universe::heap()->kind() == CollectedHeap::ParallelScavengeHeap, 61 "Sanity"); 62 assert(Universe::heap()->is_in(p), "pointer outside heap"); 63 64 claim_or_forward_internal_depth(p); 65 } 66 67 // 68 // This method is pretty bulky. It would be nice to split it up 69 // into smaller submethods, but we need to be careful not to hurt 70 // performance. 71 // 72 template<bool promote_immediately> 73 oop PSPromotionManager::copy_to_survivor_space(oop o) { 74 assert(PSScavenge::should_scavenge(&o), "Sanity"); 75 76 oop new_obj = NULL; 77 78 // NOTE! We must be very careful with any methods that access the mark 79 // in o. There may be multiple threads racing on it, and it may be forwarded 80 // at any time. Do not use oop methods for accessing the mark! 81 markOop test_mark = o->mark(); 82 83 // The same test as "o->is_forwarded()" 84 if (!test_mark->is_marked()) { 85 bool new_obj_is_tenured = false; 86 size_t new_obj_size = o->size(); 87 88 if (!promote_immediately) { 89 // Find the objects age, MT safe. 90 uint age = (test_mark->has_displaced_mark_helper() /* o->has_displaced_mark() */) ? 91 test_mark->displaced_mark_helper()->age() : test_mark->age(); 92 93 // Try allocating obj in to-space (unless too old) 94 if (age < PSScavenge::tenuring_threshold()) { 95 new_obj = (oop) _young_lab.allocate(new_obj_size); 96 if (new_obj == NULL && !_young_gen_is_full) { 97 // Do we allocate directly, or flush and refill? 98 if (new_obj_size > (YoungPLABSize / 2)) { 99 // Allocate this object directly 100 new_obj = (oop)young_space()->cas_allocate(new_obj_size); 101 } else { 102 // Flush and fill 103 _young_lab.flush(); 104 105 HeapWord* lab_base = young_space()->cas_allocate(YoungPLABSize); 106 if (lab_base != NULL) { 107 _young_lab.initialize(MemRegion(lab_base, YoungPLABSize)); 108 // Try the young lab allocation again. 109 new_obj = (oop) _young_lab.allocate(new_obj_size); 110 } else { 111 _young_gen_is_full = true; 112 } 113 } 114 } 115 } 116 } 117 118 // Otherwise try allocating obj tenured 119 if (new_obj == NULL) { 120 #ifndef PRODUCT 121 if (Universe::heap()->promotion_should_fail()) { 122 return oop_promotion_failed(o, test_mark); 123 } 124 #endif // #ifndef PRODUCT 125 126 new_obj = (oop) _old_lab.allocate(new_obj_size); 127 new_obj_is_tenured = true; 128 129 if (new_obj == NULL) { 130 if (!_old_gen_is_full) { 131 // Do we allocate directly, or flush and refill? 132 if (new_obj_size > (OldPLABSize / 2)) { 133 // Allocate this object directly 134 new_obj = (oop)old_gen()->cas_allocate(new_obj_size); 135 } else { 136 // Flush and fill 137 _old_lab.flush(); 138 139 HeapWord* lab_base = old_gen()->cas_allocate(OldPLABSize); 140 if(lab_base != NULL) { 141 #ifdef ASSERT 142 // Delay the initialization of the promotion lab (plab). 143 // This exposes uninitialized plabs to card table processing. 144 if (GCWorkerDelayMillis > 0) { 145 os::sleep(Thread::current(), GCWorkerDelayMillis, false); 146 } 147 #endif 148 _old_lab.initialize(MemRegion(lab_base, OldPLABSize)); 149 // Try the old lab allocation again. 150 new_obj = (oop) _old_lab.allocate(new_obj_size); 151 } 152 } 153 } 154 155 // This is the promotion failed test, and code handling. 156 // The code belongs here for two reasons. It is slightly 157 // different than the code below, and cannot share the 158 // CAS testing code. Keeping the code here also minimizes 159 // the impact on the common case fast path code. 160 161 if (new_obj == NULL) { 162 _old_gen_is_full = true; 163 return oop_promotion_failed(o, test_mark); 164 } 165 } 166 } 167 168 assert(new_obj != NULL, "allocation should have succeeded"); 169 170 // Copy obj 171 Copy::aligned_disjoint_words((HeapWord*)o, (HeapWord*)new_obj, new_obj_size); 172 173 // Now we have to CAS in the header. 174 if (o->cas_forward_to(new_obj, test_mark)) { 175 // We won any races, we "own" this object. 176 assert(new_obj == o->forwardee(), "Sanity"); 177 178 // Increment age if obj still in new generation. Now that 179 // we're dealing with a markOop that cannot change, it is 180 // okay to use the non mt safe oop methods. 181 if (!new_obj_is_tenured) { 182 new_obj->incr_age(); 183 assert(young_space()->contains(new_obj), "Attempt to push non-promoted obj"); 184 } 185 186 // Do the size comparison first with new_obj_size, which we 187 // already have. Hopefully, only a few objects are larger than 188 // _min_array_size_for_chunking, and most of them will be arrays. 189 // So, the is->objArray() test would be very infrequent. 190 if (new_obj_size > _min_array_size_for_chunking && 191 new_obj->is_objArray() && 192 PSChunkLargeArrays) { 193 // we'll chunk it 194 oop* const masked_o = mask_chunked_array_oop(o); 195 push_depth(masked_o); 196 TASKQUEUE_STATS_ONLY(++_arrays_chunked; ++_masked_pushes); 197 } else { 198 // we'll just push its contents 199 new_obj->push_contents(this); 200 } 201 } else { 202 // We lost, someone else "owns" this object 203 guarantee(o->is_forwarded(), "Object must be forwarded if the cas failed."); 204 205 // Try to deallocate the space. If it was directly allocated we cannot 206 // deallocate it, so we have to test. If the deallocation fails, 207 // overwrite with a filler object. 208 if (new_obj_is_tenured) { 209 if (!_old_lab.unallocate_object((HeapWord*) new_obj, new_obj_size)) { 210 CollectedHeap::fill_with_object((HeapWord*) new_obj, new_obj_size); 211 } 212 } else if (!_young_lab.unallocate_object((HeapWord*) new_obj, new_obj_size)) { 213 CollectedHeap::fill_with_object((HeapWord*) new_obj, new_obj_size); 214 } 215 216 // don't update this before the unallocation! 217 new_obj = o->forwardee(); 218 } 219 } else { 220 assert(o->is_forwarded(), "Sanity"); 221 new_obj = o->forwardee(); 222 } 223 224 #ifndef PRODUCT 225 // This code must come after the CAS test, or it will print incorrect 226 // information. 227 if (TraceScavenge) { 228 gclog_or_tty->print_cr("{%s %s " PTR_FORMAT " -> " PTR_FORMAT " (%d)}", 229 PSScavenge::should_scavenge(&new_obj) ? "copying" : "tenuring", 230 new_obj->klass()->internal_name(), p2i((void *)o), p2i((void *)new_obj), new_obj->size()); 231 } 232 #endif 233 234 return new_obj; 235 } 236 237 238 inline void PSPromotionManager::process_popped_location_depth(StarTask p) { 239 if (is_oop_masked(p)) { 240 assert(PSChunkLargeArrays, "invariant"); 241 oop const old = unmask_chunked_array_oop(p); 242 process_array_chunk(old); 243 } else { 244 if (p.is_narrow()) { 245 assert(UseCompressedOops, "Error"); 246 PSScavenge::copy_and_push_safe_barrier<narrowOop, /*promote_immediately=*/false>(this, p); 247 } else { 248 PSScavenge::copy_and_push_safe_barrier<oop, /*promote_immediately=*/false>(this, p); 249 } 250 } 251 } 252 253 #if TASKQUEUE_STATS 254 void PSPromotionManager::record_steal(StarTask& p) { 255 if (is_oop_masked(p)) { 256 ++_masked_steals; 257 } 258 } 259 #endif // TASKQUEUE_STATS 260 261 #endif // SHARE_VM_GC_IMPLEMENTATION_PARALLELSCAVENGE_PSPROMOTIONMANAGER_INLINE_HPP